1 /* Output variables, constants and external declarations, for GNU compiler.
2    Copyright (C) 1987-2019 Free Software Foundation, Inc.
3 
4 This file is part of GCC.
5 
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
10 
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 for more details.
15 
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3.  If not see
18 <http://www.gnu.org/licenses/>.  */
19 
20 
21 /* This file handles generation of all the assembler code
22    *except* the instructions of a function.
23    This includes declarations of variables and their initial values.
24 
25    We also output the assembler code for constants stored in memory
26    and are responsible for combining constants with the same value.  */
27 
28 #include "config.h"
29 #include "system.h"
30 #include "coretypes.h"
31 #include "backend.h"
32 #include "target.h"
33 #include "rtl.h"
34 #include "tree.h"
35 #include "predict.h"
36 #include "memmodel.h"
37 #include "tm_p.h"
38 #include "stringpool.h"
39 #include "regs.h"
40 #include "emit-rtl.h"
41 #include "cgraph.h"
42 #include "diagnostic-core.h"
43 #include "fold-const.h"
44 #include "stor-layout.h"
45 #include "varasm.h"
46 #include "flags.h"
47 #include "stmt.h"
48 #include "expr.h"
49 #include "expmed.h"
50 #include "output.h"
51 #include "langhooks.h"
52 #include "debug.h"
53 #include "common/common-target.h"
54 #include "stringpool.h"
55 #include "attribs.h"
56 #include "asan.h"
57 #include "rtl-iter.h"
58 #include "file-prefix-map.h" /* remap_debug_filename()  */
59 
60 #ifdef XCOFF_DEBUGGING_INFO
61 #include "xcoffout.h"		/* Needed for external data declarations.  */
62 #endif
63 
64 /* The (assembler) name of the first globally-visible object output.  */
65 extern GTY(()) const char *first_global_object_name;
66 extern GTY(()) const char *weak_global_object_name;
67 
68 const char *first_global_object_name;
69 const char *weak_global_object_name;
70 
71 struct addr_const;
72 struct constant_descriptor_rtx;
73 struct rtx_constant_pool;
74 
75 #define n_deferred_constants (crtl->varasm.deferred_constants)
76 
77 /* Number for making the label on the next
78    constant that is stored in memory.  */
79 
80 static GTY(()) int const_labelno;
81 
82 /* Carry information from ASM_DECLARE_OBJECT_NAME
83    to ASM_FINISH_DECLARE_OBJECT.  */
84 
85 int size_directive_output;
86 
87 /* The last decl for which assemble_variable was called,
88    if it did ASM_DECLARE_OBJECT_NAME.
89    If the last call to assemble_variable didn't do that,
90    this holds 0.  */
91 
92 tree last_assemble_variable_decl;
93 
94 /* The following global variable indicates if the first basic block
95    in a function belongs to the cold partition or not.  */
96 
97 bool first_function_block_is_cold;
98 
99 /* Whether we saw any functions with no_split_stack.  */
100 
101 static bool saw_no_split_stack;
102 
103 static const char *strip_reg_name (const char *);
104 static int contains_pointers_p (tree);
105 #ifdef ASM_OUTPUT_EXTERNAL
106 static bool incorporeal_function_p (tree);
107 #endif
108 static void decode_addr_const (tree, struct addr_const *);
109 static hashval_t const_hash_1 (const tree);
110 static int compare_constant (const tree, const tree);
111 static void output_constant_def_contents (rtx);
112 static void output_addressed_constants (tree);
113 static unsigned HOST_WIDE_INT output_constant (tree, unsigned HOST_WIDE_INT,
114 					       unsigned int, bool, bool);
115 static void globalize_decl (tree);
116 static bool decl_readonly_section_1 (enum section_category);
117 #ifdef BSS_SECTION_ASM_OP
118 #ifdef ASM_OUTPUT_ALIGNED_BSS
119 static void asm_output_aligned_bss (FILE *, tree, const char *,
120 				    unsigned HOST_WIDE_INT, int)
121      ATTRIBUTE_UNUSED;
122 #endif
123 #endif /* BSS_SECTION_ASM_OP */
124 static void mark_weak (tree);
125 static void output_constant_pool (const char *, tree);
126 static void handle_vtv_comdat_section (section *, const_tree);
127 
128 /* Well-known sections, each one associated with some sort of *_ASM_OP.  */
129 section *text_section;
130 section *data_section;
131 section *readonly_data_section;
132 section *sdata_section;
133 section *ctors_section;
134 section *dtors_section;
135 section *bss_section;
136 section *sbss_section;
137 
138 /* Various forms of common section.  All are guaranteed to be nonnull.  */
139 section *tls_comm_section;
140 section *comm_section;
141 section *lcomm_section;
142 
143 /* A SECTION_NOSWITCH section used for declaring global BSS variables.
144    May be null.  */
145 section *bss_noswitch_section;
146 
147 /* The section that holds the main exception table, when known.  The section
148    is set either by the target's init_sections hook or by the first call to
149    switch_to_exception_section.  */
150 section *exception_section;
151 
152 /* The section that holds the DWARF2 frame unwind information, when known.
153    The section is set either by the target's init_sections hook or by the
154    first call to switch_to_eh_frame_section.  */
155 section *eh_frame_section;
156 
157 /* asm_out_file's current section.  This is NULL if no section has yet
158    been selected or if we lose track of what the current section is.  */
159 section *in_section;
160 
161 /* True if code for the current function is currently being directed
162    at the cold section.  */
163 bool in_cold_section_p;
164 
165 /* The following global holds the "function name" for the code in the
166    cold section of a function, if hot/cold function splitting is enabled
167    and there was actually code that went into the cold section.  A
168    pseudo function name is needed for the cold section of code for some
169    debugging tools that perform symbolization. */
170 tree cold_function_name = NULL_TREE;
171 
172 /* A linked list of all the unnamed sections.  */
173 static GTY(()) section *unnamed_sections;
174 
175 /* Return a nonzero value if DECL has a section attribute.  */
176 #define IN_NAMED_SECTION(DECL) \
177   (VAR_OR_FUNCTION_DECL_P (DECL) && DECL_SECTION_NAME (DECL) != NULL)
178 
179 struct section_hasher : ggc_ptr_hash<section>
180 {
181   typedef const char *compare_type;
182 
183   static hashval_t hash (section *);
184   static bool equal (section *, const char *);
185 };
186 
187 /* Hash table of named sections.  */
188 static GTY(()) hash_table<section_hasher> *section_htab;
189 
190 struct object_block_hasher : ggc_ptr_hash<object_block>
191 {
192   typedef const section *compare_type;
193 
194   static hashval_t hash (object_block *);
195   static bool equal (object_block *, const section *);
196 };
197 
198 /* A table of object_blocks, indexed by section.  */
199 static GTY(()) hash_table<object_block_hasher> *object_block_htab;
200 
201 /* The next number to use for internal anchor labels.  */
202 static GTY(()) int anchor_labelno;
203 
204 /* A pool of constants that can be shared between functions.  */
205 static GTY(()) struct rtx_constant_pool *shared_constant_pool;
206 
207 /* Helper routines for maintaining section_htab.  */
208 
209 bool
equal(section * old,const char * new_name)210 section_hasher::equal (section *old, const char *new_name)
211 {
212   return strcmp (old->named.name, new_name) == 0;
213 }
214 
215 hashval_t
hash(section * old)216 section_hasher::hash (section *old)
217 {
218   return htab_hash_string (old->named.name);
219 }
220 
221 /* Return a hash value for section SECT.  */
222 
223 static hashval_t
hash_section(section * sect)224 hash_section (section *sect)
225 {
226   if (sect->common.flags & SECTION_NAMED)
227     return htab_hash_string (sect->named.name);
228   return sect->common.flags & ~SECTION_DECLARED;
229 }
230 
231 /* Helper routines for maintaining object_block_htab.  */
232 
233 inline bool
equal(object_block * old,const section * new_section)234 object_block_hasher::equal (object_block *old, const section *new_section)
235 {
236   return old->sect == new_section;
237 }
238 
239 hashval_t
hash(object_block * old)240 object_block_hasher::hash (object_block *old)
241 {
242   return hash_section (old->sect);
243 }
244 
245 /* Return a new unnamed section with the given fields.  */
246 
247 section *
get_unnamed_section(unsigned int flags,void (* callback)(const void *),const void * data)248 get_unnamed_section (unsigned int flags, void (*callback) (const void *),
249 		     const void *data)
250 {
251   section *sect;
252 
253   sect = ggc_alloc<section> ();
254   sect->unnamed.common.flags = flags | SECTION_UNNAMED;
255   sect->unnamed.callback = callback;
256   sect->unnamed.data = data;
257   sect->unnamed.next = unnamed_sections;
258 
259   unnamed_sections = sect;
260   return sect;
261 }
262 
263 /* Return a SECTION_NOSWITCH section with the given fields.  */
264 
265 static section *
get_noswitch_section(unsigned int flags,noswitch_section_callback callback)266 get_noswitch_section (unsigned int flags, noswitch_section_callback callback)
267 {
268   section *sect;
269 
270   sect = ggc_alloc<section> ();
271   sect->noswitch.common.flags = flags | SECTION_NOSWITCH;
272   sect->noswitch.callback = callback;
273 
274   return sect;
275 }
276 
277 /* Return the named section structure associated with NAME.  Create
278    a new section with the given fields if no such structure exists.  */
279 
280 section *
get_section(const char * name,unsigned int flags,tree decl)281 get_section (const char *name, unsigned int flags, tree decl)
282 {
283   section *sect, **slot;
284 
285   slot = section_htab->find_slot_with_hash (name, htab_hash_string (name),
286 					    INSERT);
287   flags |= SECTION_NAMED;
288   if (*slot == NULL)
289     {
290       sect = ggc_alloc<section> ();
291       sect->named.common.flags = flags;
292       sect->named.name = ggc_strdup (name);
293       sect->named.decl = decl;
294       *slot = sect;
295     }
296   else
297     {
298       sect = *slot;
299       /* It is fine if one of the sections has SECTION_NOTYPE as long as
300          the other has none of the contrary flags (see the logic at the end
301          of default_section_type_flags, below).  */
302       if (((sect->common.flags ^ flags) & SECTION_NOTYPE)
303           && !((sect->common.flags | flags)
304                & (SECTION_CODE | SECTION_BSS | SECTION_TLS | SECTION_ENTSIZE
305                   | (HAVE_COMDAT_GROUP ? SECTION_LINKONCE : 0))))
306         {
307           sect->common.flags |= SECTION_NOTYPE;
308           flags |= SECTION_NOTYPE;
309         }
310       if ((sect->common.flags & ~SECTION_DECLARED) != flags
311 	  && ((sect->common.flags | flags) & SECTION_OVERRIDE) == 0)
312 	{
313 	  /* It is fine if one of the section flags is
314 	     SECTION_WRITE | SECTION_RELRO and the other has none of these
315 	     flags (i.e. read-only) in named sections and either the
316 	     section hasn't been declared yet or has been declared as writable.
317 	     In that case just make sure the resulting flags are
318 	     SECTION_WRITE | SECTION_RELRO, ie. writable only because of
319 	     relocations.  */
320 	  if (((sect->common.flags ^ flags) & (SECTION_WRITE | SECTION_RELRO))
321 	      == (SECTION_WRITE | SECTION_RELRO)
322 	      && (sect->common.flags
323 		  & ~(SECTION_DECLARED | SECTION_WRITE | SECTION_RELRO))
324 		 == (flags & ~(SECTION_WRITE | SECTION_RELRO))
325 	      && ((sect->common.flags & SECTION_DECLARED) == 0
326 		  || (sect->common.flags & SECTION_WRITE)))
327 	    {
328 	      sect->common.flags |= (SECTION_WRITE | SECTION_RELRO);
329 	      return sect;
330 	    }
331 	  /* Sanity check user variables for flag changes.  */
332 	  if (sect->named.decl != NULL
333 	      && DECL_P (sect->named.decl)
334 	      && decl != sect->named.decl)
335 	    {
336 	      if (decl != NULL && DECL_P (decl))
337 		error ("%+qD causes a section type conflict with %qD",
338 		       decl, sect->named.decl);
339 	      else
340 		error ("section type conflict with %qD", sect->named.decl);
341 	      inform (DECL_SOURCE_LOCATION (sect->named.decl),
342 		      "%qD was declared here", sect->named.decl);
343 	    }
344 	  else if (decl != NULL && DECL_P (decl))
345 	    error ("%+qD causes a section type conflict", decl);
346 	  else
347 	    error ("section type conflict");
348 	  /* Make sure we don't error about one section multiple times.  */
349 	  sect->common.flags |= SECTION_OVERRIDE;
350 	}
351     }
352   return sect;
353 }
354 
355 /* Return true if the current compilation mode benefits from having
356    objects grouped into blocks.  */
357 
358 static bool
use_object_blocks_p(void)359 use_object_blocks_p (void)
360 {
361   return flag_section_anchors;
362 }
363 
364 /* Return the object_block structure for section SECT.  Create a new
365    structure if we haven't created one already.  Return null if SECT
366    itself is null.  Return also null for mergeable sections since
367    section anchors can't be used in mergeable sections anyway,
368    because the linker might move objects around, and using the
369    object blocks infrastructure in that case is both a waste and a
370    maintenance burden.  */
371 
372 static struct object_block *
get_block_for_section(section * sect)373 get_block_for_section (section *sect)
374 {
375   struct object_block *block;
376 
377   if (sect == NULL)
378     return NULL;
379 
380   if (sect->common.flags & SECTION_MERGE)
381     return NULL;
382 
383   object_block **slot
384     = object_block_htab->find_slot_with_hash (sect, hash_section (sect),
385 					      INSERT);
386   block = *slot;
387   if (block == NULL)
388     {
389       block = ggc_cleared_alloc<object_block> ();
390       block->sect = sect;
391       *slot = block;
392     }
393   return block;
394 }
395 
396 /* Create a symbol with label LABEL and place it at byte offset
397    OFFSET in BLOCK.  OFFSET can be negative if the symbol's offset
398    is not yet known.  LABEL must be a garbage-collected string.  */
399 
400 static rtx
create_block_symbol(const char * label,struct object_block * block,HOST_WIDE_INT offset)401 create_block_symbol (const char *label, struct object_block *block,
402 		     HOST_WIDE_INT offset)
403 {
404   rtx symbol;
405   unsigned int size;
406 
407   /* Create the extended SYMBOL_REF.  */
408   size = RTX_HDR_SIZE + sizeof (struct block_symbol);
409   symbol = (rtx) ggc_internal_alloc (size);
410 
411   /* Initialize the normal SYMBOL_REF fields.  */
412   memset (symbol, 0, size);
413   PUT_CODE (symbol, SYMBOL_REF);
414   PUT_MODE (symbol, Pmode);
415   XSTR (symbol, 0) = label;
416   SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_HAS_BLOCK_INFO;
417 
418   /* Initialize the block_symbol stuff.  */
419   SYMBOL_REF_BLOCK (symbol) = block;
420   SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
421 
422   return symbol;
423 }
424 
425 /* Return a section with a particular name and with whatever SECTION_*
426    flags section_type_flags deems appropriate.  The name of the section
427    is taken from NAME if nonnull, otherwise it is taken from DECL's
428    DECL_SECTION_NAME.  DECL is the decl associated with the section
429    (see the section comment for details) and RELOC is as for
430    section_type_flags.  */
431 
432 section *
get_named_section(tree decl,const char * name,int reloc)433 get_named_section (tree decl, const char *name, int reloc)
434 {
435   unsigned int flags;
436 
437   if (name == NULL)
438     {
439       gcc_assert (decl && DECL_P (decl) && DECL_SECTION_NAME (decl));
440       name = DECL_SECTION_NAME (decl);
441     }
442 
443   flags = targetm.section_type_flags (decl, name, reloc);
444   return get_section (name, flags, decl);
445 }
446 
447 /* Worker for resolve_unique_section.  */
448 
449 static bool
set_implicit_section(struct symtab_node * n,void * data ATTRIBUTE_UNUSED)450 set_implicit_section (struct symtab_node *n, void *data ATTRIBUTE_UNUSED)
451 {
452   n->implicit_section = true;
453   return false;
454 }
455 
456 /* If required, set DECL_SECTION_NAME to a unique name.  */
457 
458 void
resolve_unique_section(tree decl,int reloc ATTRIBUTE_UNUSED,int flag_function_or_data_sections)459 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
460 			int flag_function_or_data_sections)
461 {
462   if (DECL_SECTION_NAME (decl) == NULL
463       && targetm_common.have_named_sections
464       && (flag_function_or_data_sections
465 	  || DECL_COMDAT_GROUP (decl)))
466     {
467       targetm.asm_out.unique_section (decl, reloc);
468       if (DECL_SECTION_NAME (decl))
469 	symtab_node::get (decl)->call_for_symbol_and_aliases
470 	  (set_implicit_section, NULL, true);
471     }
472 }
473 
474 #ifdef BSS_SECTION_ASM_OP
475 
476 #ifdef ASM_OUTPUT_ALIGNED_BSS
477 
478 /* Utility function for targets to use in implementing
479    ASM_OUTPUT_ALIGNED_BSS.
480    ??? It is believed that this function will work in most cases so such
481    support is localized here.  */
482 
483 static void
asm_output_aligned_bss(FILE * file,tree decl ATTRIBUTE_UNUSED,const char * name,unsigned HOST_WIDE_INT size,int align)484 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
485 			const char *name, unsigned HOST_WIDE_INT size,
486 			int align)
487 {
488   switch_to_section (bss_section);
489   ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
490 #ifdef ASM_DECLARE_OBJECT_NAME
491   last_assemble_variable_decl = decl;
492   ASM_DECLARE_OBJECT_NAME (file, name, decl);
493 #else
494   /* Standard thing is just output label for the object.  */
495   ASM_OUTPUT_LABEL (file, name);
496 #endif /* ASM_DECLARE_OBJECT_NAME */
497   ASM_OUTPUT_SKIP (file, size ? size : 1);
498 }
499 
500 #endif
501 
502 #endif /* BSS_SECTION_ASM_OP */
503 
504 #ifndef USE_SELECT_SECTION_FOR_FUNCTIONS
505 /* Return the hot section for function DECL.  Return text_section for
506    null DECLs.  */
507 
508 static section *
hot_function_section(tree decl)509 hot_function_section (tree decl)
510 {
511   if (decl != NULL_TREE
512       && DECL_SECTION_NAME (decl) != NULL
513       && targetm_common.have_named_sections)
514     return get_named_section (decl, NULL, 0);
515   else
516     return text_section;
517 }
518 #endif
519 
520 /* Return section for TEXT_SECTION_NAME if DECL or DECL_SECTION_NAME (DECL)
521    is NULL.
522 
523    When DECL_SECTION_NAME is non-NULL and it is implicit section and
524    NAMED_SECTION_SUFFIX is non-NULL, then produce section called
525    concatenate the name with NAMED_SECTION_SUFFIX.
526    Otherwise produce "TEXT_SECTION_NAME.IMPLICIT_NAME".  */
527 
528 section *
get_named_text_section(tree decl,const char * text_section_name,const char * named_section_suffix)529 get_named_text_section (tree decl,
530 		        const char *text_section_name,
531 		        const char *named_section_suffix)
532 {
533   if (decl && DECL_SECTION_NAME (decl))
534     {
535       if (named_section_suffix)
536 	{
537 	  const char *dsn = DECL_SECTION_NAME (decl);
538 	  const char *stripped_name;
539 	  char *name, *buffer;
540 
541 	  name = (char *) alloca (strlen (dsn) + 1);
542 	  memcpy (name, dsn,
543 		  strlen (dsn) + 1);
544 
545 	  stripped_name = targetm.strip_name_encoding (name);
546 
547 	  buffer = ACONCAT ((stripped_name, named_section_suffix, NULL));
548 	  return get_named_section (decl, buffer, 0);
549 	}
550       else if (symtab_node::get (decl)->implicit_section)
551 	{
552 	  const char *name;
553 
554 	  /* Do not try to split gnu_linkonce functions.  This gets somewhat
555 	     slipperly.  */
556 	  if (DECL_COMDAT_GROUP (decl) && !HAVE_COMDAT_GROUP)
557 	    return NULL;
558 	  name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
559 	  name = targetm.strip_name_encoding (name);
560 	  return get_named_section (decl, ACONCAT ((text_section_name, ".",
561 				                   name, NULL)), 0);
562 	}
563       else
564 	return NULL;
565     }
566   return get_named_section (decl, text_section_name, 0);
567 }
568 
569 /* Choose named function section based on its frequency.  */
570 
571 section *
default_function_section(tree decl,enum node_frequency freq,bool startup,bool exit)572 default_function_section (tree decl, enum node_frequency freq,
573 			  bool startup, bool exit)
574 {
575 #if defined HAVE_LD_EH_GC_SECTIONS && defined HAVE_LD_EH_GC_SECTIONS_BUG
576   /* Old GNU linkers have buggy --gc-section support, which sometimes
577      results in .gcc_except_table* sections being garbage collected.  */
578   if (decl
579       && symtab_node::get (decl)->implicit_section)
580     return NULL;
581 #endif
582 
583   if (!flag_reorder_functions
584       || !targetm_common.have_named_sections)
585     return NULL;
586   /* Startup code should go to startup subsection unless it is
587      unlikely executed (this happens especially with function splitting
588      where we can split away unnecessary parts of static constructors.  */
589   if (startup && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
590   {
591     /* If we do have a profile or(and) LTO phase is executed, we do not need
592        these ELF section.  */
593     if (!in_lto_p || !flag_profile_values)
594       return get_named_text_section (decl, ".text.startup", NULL);
595     else
596       return NULL;
597   }
598 
599   /* Similarly for exit.  */
600   if (exit && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
601     return get_named_text_section (decl, ".text.exit", NULL);
602 
603   /* Group cold functions together, similarly for hot code.  */
604   switch (freq)
605     {
606       case NODE_FREQUENCY_UNLIKELY_EXECUTED:
607 	return get_named_text_section (decl, ".text.unlikely", NULL);
608       case NODE_FREQUENCY_HOT:
609         /* If we do have a profile or(and) LTO phase is executed, we do not need
610            these ELF section.  */
611         if (!in_lto_p || !flag_profile_values)
612           return get_named_text_section (decl, ".text.hot", NULL);
613 	/* FALLTHRU */
614       default:
615 	return NULL;
616     }
617 }
618 
619 /* Return the section for function DECL.
620 
621    If DECL is NULL_TREE, return the text section.  We can be passed
622    NULL_TREE under some circumstances by dbxout.c at least.
623 
624    If FORCE_COLD is true, return cold function section ignoring
625    the frequency info of cgraph_node.  */
626 
627 static section *
function_section_1(tree decl,bool force_cold)628 function_section_1 (tree decl, bool force_cold)
629 {
630   section *section = NULL;
631   enum node_frequency freq = NODE_FREQUENCY_NORMAL;
632   bool startup = false, exit = false;
633 
634   if (decl)
635     {
636       struct cgraph_node *node = cgraph_node::get (decl);
637 
638       if (node)
639 	{
640 	  freq = node->frequency;
641 	  startup = node->only_called_at_startup;
642 	  exit = node->only_called_at_exit;
643 	}
644     }
645   if (force_cold)
646     freq = NODE_FREQUENCY_UNLIKELY_EXECUTED;
647 
648 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
649   if (decl != NULL_TREE
650       && DECL_SECTION_NAME (decl) != NULL)
651     {
652       if (targetm.asm_out.function_section)
653 	section = targetm.asm_out.function_section (decl, freq,
654 						    startup, exit);
655       if (section)
656 	return section;
657       return get_named_section (decl, NULL, 0);
658     }
659   else
660     return targetm.asm_out.select_section
661 	    (decl, freq == NODE_FREQUENCY_UNLIKELY_EXECUTED,
662 	     symtab_node::get (decl)->definition_alignment ());
663 #else
664   if (targetm.asm_out.function_section)
665     section = targetm.asm_out.function_section (decl, freq, startup, exit);
666   if (section)
667     return section;
668   return hot_function_section (decl);
669 #endif
670 }
671 
672 /* Return the section for function DECL.
673 
674    If DECL is NULL_TREE, return the text section.  We can be passed
675    NULL_TREE under some circumstances by dbxout.c at least.  */
676 
677 section *
function_section(tree decl)678 function_section (tree decl)
679 {
680   /* Handle cases where function splitting code decides
681      to put function entry point into unlikely executed section
682      despite the fact that the function itself is not cold
683      (i.e. it is called rarely but contains a hot loop that is
684      better to live in hot subsection for the code locality).  */
685   return function_section_1 (decl,
686 			     first_function_block_is_cold);
687 }
688 
689 /* Return the section for the current function, take IN_COLD_SECTION_P
690    into account.  */
691 
692 section *
current_function_section(void)693 current_function_section (void)
694 {
695   return function_section_1 (current_function_decl, in_cold_section_p);
696 }
697 
698 /* Tell assembler to switch to unlikely-to-be-executed text section.  */
699 
700 section *
unlikely_text_section(void)701 unlikely_text_section (void)
702 {
703   return function_section_1 (current_function_decl, true);
704 }
705 
706 /* When called within a function context, return true if the function
707    has been assigned a cold text section and if SECT is that section.
708    When called outside a function context, return true if SECT is the
709    default cold section.  */
710 
711 bool
unlikely_text_section_p(section * sect)712 unlikely_text_section_p (section *sect)
713 {
714   return sect == function_section_1 (current_function_decl, true);
715 }
716 
717 /* Switch to the other function partition (if inside of hot section
718    into cold section, otherwise into the hot section).  */
719 
720 void
switch_to_other_text_partition(void)721 switch_to_other_text_partition (void)
722 {
723   in_cold_section_p = !in_cold_section_p;
724   switch_to_section (current_function_section ());
725 }
726 
727 /* Return the read-only data section associated with function DECL.  */
728 
729 section *
default_function_rodata_section(tree decl)730 default_function_rodata_section (tree decl)
731 {
732   if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
733     {
734       const char *name = DECL_SECTION_NAME (decl);
735 
736       if (DECL_COMDAT_GROUP (decl) && HAVE_COMDAT_GROUP)
737         {
738 	  const char *dot;
739 	  size_t len;
740 	  char* rname;
741 
742 	  dot = strchr (name + 1, '.');
743 	  if (!dot)
744 	    dot = name;
745 	  len = strlen (dot) + 8;
746 	  rname = (char *) alloca (len);
747 
748 	  strcpy (rname, ".rodata");
749 	  strcat (rname, dot);
750 	  return get_section (rname, SECTION_LINKONCE, decl);
751 	}
752       /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo.  */
753       else if (DECL_COMDAT_GROUP (decl)
754 	       && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
755 	{
756 	  size_t len = strlen (name) + 1;
757 	  char *rname = (char *) alloca (len);
758 
759 	  memcpy (rname, name, len);
760 	  rname[14] = 'r';
761 	  return get_section (rname, SECTION_LINKONCE, decl);
762 	}
763       /* For .text.foo we want to use .rodata.foo.  */
764       else if (flag_function_sections && flag_data_sections
765 	       && strncmp (name, ".text.", 6) == 0)
766 	{
767 	  size_t len = strlen (name) + 1;
768 	  char *rname = (char *) alloca (len + 2);
769 
770 	  memcpy (rname, ".rodata", 7);
771 	  memcpy (rname + 7, name + 5, len - 5);
772 	  return get_section (rname, 0, decl);
773 	}
774     }
775 
776   return readonly_data_section;
777 }
778 
779 /* Return the read-only data section associated with function DECL
780    for targets where that section should be always the single
781    readonly data section.  */
782 
783 section *
default_no_function_rodata_section(tree decl ATTRIBUTE_UNUSED)784 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
785 {
786   return readonly_data_section;
787 }
788 
789 /* A subroutine of mergeable_string_section and mergeable_constant_section.  */
790 
791 static const char *
function_mergeable_rodata_prefix(void)792 function_mergeable_rodata_prefix (void)
793 {
794   section *s = targetm.asm_out.function_rodata_section (current_function_decl);
795   if (SECTION_STYLE (s) == SECTION_NAMED)
796     return s->named.name;
797   else
798     return targetm.asm_out.mergeable_rodata_prefix;
799 }
800 
801 /* Return the section to use for string merging.  */
802 
803 static section *
mergeable_string_section(tree decl ATTRIBUTE_UNUSED,unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,unsigned int flags ATTRIBUTE_UNUSED)804 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
805 			  unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
806 			  unsigned int flags ATTRIBUTE_UNUSED)
807 {
808   HOST_WIDE_INT len;
809 
810   if (HAVE_GAS_SHF_MERGE && flag_merge_constants
811       && TREE_CODE (decl) == STRING_CST
812       && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
813       && align <= 256
814       && (len = int_size_in_bytes (TREE_TYPE (decl))) > 0
815       && TREE_STRING_LENGTH (decl) == len)
816     {
817       scalar_int_mode mode;
818       unsigned int modesize;
819       const char *str;
820       HOST_WIDE_INT i;
821       int j, unit;
822       const char *prefix = function_mergeable_rodata_prefix ();
823       char *name = (char *) alloca (strlen (prefix) + 30);
824 
825       mode = SCALAR_INT_TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
826       modesize = GET_MODE_BITSIZE (mode);
827       if (modesize >= 8 && modesize <= 256
828 	  && (modesize & (modesize - 1)) == 0)
829 	{
830 	  if (align < modesize)
831 	    align = modesize;
832 
833 	  if (!HAVE_LD_ALIGNED_SHF_MERGE && align > 8)
834 	    return readonly_data_section;
835 
836 	  str = TREE_STRING_POINTER (decl);
837 	  unit = GET_MODE_SIZE (mode);
838 
839 	  /* Check for embedded NUL characters.  */
840 	  for (i = 0; i < len; i += unit)
841 	    {
842 	      for (j = 0; j < unit; j++)
843 		if (str[i + j] != '\0')
844 		  break;
845 	      if (j == unit)
846 		break;
847 	    }
848 	  if (i == len - unit || (unit == 1 && i == len))
849 	    {
850 	      sprintf (name, "%s.str%d.%d", prefix,
851 		       modesize / 8, (int) (align / 8));
852 	      flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
853 	      return get_section (name, flags, NULL);
854 	    }
855 	}
856     }
857 
858   return readonly_data_section;
859 }
860 
861 /* Return the section to use for constant merging.  */
862 
863 section *
mergeable_constant_section(machine_mode mode ATTRIBUTE_UNUSED,unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,unsigned int flags ATTRIBUTE_UNUSED)864 mergeable_constant_section (machine_mode mode ATTRIBUTE_UNUSED,
865 			    unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
866 			    unsigned int flags ATTRIBUTE_UNUSED)
867 {
868   if (HAVE_GAS_SHF_MERGE && flag_merge_constants
869       && mode != VOIDmode
870       && mode != BLKmode
871       && known_le (GET_MODE_BITSIZE (mode), align)
872       && align >= 8
873       && align <= 256
874       && (align & (align - 1)) == 0
875       && (HAVE_LD_ALIGNED_SHF_MERGE ? 1 : align == 8))
876     {
877       const char *prefix = function_mergeable_rodata_prefix ();
878       char *name = (char *) alloca (strlen (prefix) + 30);
879 
880       sprintf (name, "%s.cst%d", prefix, (int) (align / 8));
881       flags |= (align / 8) | SECTION_MERGE;
882       return get_section (name, flags, NULL);
883     }
884   return readonly_data_section;
885 }
886 
887 /* Given NAME, a putative register name, discard any customary prefixes.  */
888 
889 static const char *
strip_reg_name(const char * name)890 strip_reg_name (const char *name)
891 {
892 #ifdef REGISTER_PREFIX
893   if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
894     name += strlen (REGISTER_PREFIX);
895 #endif
896   if (name[0] == '%' || name[0] == '#')
897     name++;
898   return name;
899 }
900 
901 /* The user has asked for a DECL to have a particular name.  Set (or
902    change) it in such a way that we don't prefix an underscore to
903    it.  */
904 void
set_user_assembler_name(tree decl,const char * name)905 set_user_assembler_name (tree decl, const char *name)
906 {
907   char *starred = (char *) alloca (strlen (name) + 2);
908   starred[0] = '*';
909   strcpy (starred + 1, name);
910   symtab->change_decl_assembler_name (decl, get_identifier (starred));
911   SET_DECL_RTL (decl, NULL_RTX);
912 }
913 
914 /* Decode an `asm' spec for a declaration as a register name.
915    Return the register number, or -1 if nothing specified,
916    or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
917    or -3 if ASMSPEC is `cc' and is not recognized,
918    or -4 if ASMSPEC is `memory' and is not recognized.
919    Accept an exact spelling or a decimal number.
920    Prefixes such as % are optional.  */
921 
922 int
decode_reg_name_and_count(const char * asmspec,int * pnregs)923 decode_reg_name_and_count (const char *asmspec, int *pnregs)
924 {
925   /* Presume just one register is clobbered.  */
926   *pnregs = 1;
927 
928   if (asmspec != 0)
929     {
930       int i;
931 
932       /* Get rid of confusing prefixes.  */
933       asmspec = strip_reg_name (asmspec);
934 
935       /* Allow a decimal number as a "register name".  */
936       for (i = strlen (asmspec) - 1; i >= 0; i--)
937 	if (! ISDIGIT (asmspec[i]))
938 	  break;
939       if (asmspec[0] != 0 && i < 0)
940 	{
941 	  i = atoi (asmspec);
942 	  if (i < FIRST_PSEUDO_REGISTER && i >= 0 && reg_names[i][0])
943 	    return i;
944 	  else
945 	    return -2;
946 	}
947 
948       for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
949 	if (reg_names[i][0]
950 	    && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
951 	  return i;
952 
953 #ifdef OVERLAPPING_REGISTER_NAMES
954       {
955 	static const struct
956 	{
957 	  const char *const name;
958 	  const int number;
959 	  const int nregs;
960 	} table[] = OVERLAPPING_REGISTER_NAMES;
961 
962 	for (i = 0; i < (int) ARRAY_SIZE (table); i++)
963 	  if (table[i].name[0]
964 	      && ! strcmp (asmspec, table[i].name))
965 	    {
966 	      *pnregs = table[i].nregs;
967 	      return table[i].number;
968 	    }
969       }
970 #endif /* OVERLAPPING_REGISTER_NAMES */
971 
972 #ifdef ADDITIONAL_REGISTER_NAMES
973       {
974 	static const struct { const char *const name; const int number; } table[]
975 	  = ADDITIONAL_REGISTER_NAMES;
976 
977 	for (i = 0; i < (int) ARRAY_SIZE (table); i++)
978 	  if (table[i].name[0]
979 	      && ! strcmp (asmspec, table[i].name)
980 	      && reg_names[table[i].number][0])
981 	    return table[i].number;
982       }
983 #endif /* ADDITIONAL_REGISTER_NAMES */
984 
985       if (!strcmp (asmspec, "memory"))
986 	return -4;
987 
988       if (!strcmp (asmspec, "cc"))
989 	return -3;
990 
991       return -2;
992     }
993 
994   return -1;
995 }
996 
997 int
decode_reg_name(const char * name)998 decode_reg_name (const char *name)
999 {
1000   int count;
1001   return decode_reg_name_and_count (name, &count);
1002 }
1003 
1004 
1005 /* Return true if DECL's initializer is suitable for a BSS section.  */
1006 
1007 bool
bss_initializer_p(const_tree decl,bool named)1008 bss_initializer_p (const_tree decl, bool named)
1009 {
1010   /* Do not put non-common constants into the .bss section, they belong in
1011      a readonly section, except when NAMED is true.  */
1012   return ((!TREE_READONLY (decl) || DECL_COMMON (decl) || named)
1013 	  && (DECL_INITIAL (decl) == NULL
1014 	      /* In LTO we have no errors in program; error_mark_node is used
1015 	         to mark offlined constructors.  */
1016 	      || (DECL_INITIAL (decl) == error_mark_node
1017 	          && !in_lto_p)
1018 	      || (flag_zero_initialized_in_bss
1019 	          && initializer_zerop (DECL_INITIAL (decl)))));
1020 }
1021 
1022 /* Compute the alignment of variable specified by DECL.
1023    DONT_OUTPUT_DATA is from assemble_variable.  */
1024 
1025 void
align_variable(tree decl,bool dont_output_data)1026 align_variable (tree decl, bool dont_output_data)
1027 {
1028   unsigned int align = DECL_ALIGN (decl);
1029 
1030   /* In the case for initialing an array whose length isn't specified,
1031      where we have not yet been able to do the layout,
1032      figure out the proper alignment now.  */
1033   if (dont_output_data && DECL_SIZE (decl) == 0
1034       && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
1035     align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
1036 
1037   /* Some object file formats have a maximum alignment which they support.
1038      In particular, a.out format supports a maximum alignment of 4.  */
1039   if (align > MAX_OFILE_ALIGNMENT)
1040     {
1041       error ("alignment of %q+D is greater than maximum object "
1042 	     "file alignment %d", decl,
1043 	     MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
1044       align = MAX_OFILE_ALIGNMENT;
1045     }
1046 
1047   if (! DECL_USER_ALIGN (decl))
1048     {
1049 #ifdef DATA_ABI_ALIGNMENT
1050       unsigned int data_abi_align
1051 	= DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1052       /* For backwards compatibility, don't assume the ABI alignment for
1053 	 TLS variables.  */
1054       if (! DECL_THREAD_LOCAL_P (decl) || data_abi_align <= BITS_PER_WORD)
1055 	align = data_abi_align;
1056 #endif
1057 
1058       /* On some machines, it is good to increase alignment sometimes.
1059 	 But as DECL_ALIGN is used both for actually emitting the variable
1060 	 and for code accessing the variable as guaranteed alignment, we
1061 	 can only increase the alignment if it is a performance optimization
1062 	 if the references to it must bind to the current definition.  */
1063       if (decl_binds_to_current_def_p (decl)
1064 	  && !DECL_VIRTUAL_P (decl))
1065 	{
1066 #ifdef DATA_ALIGNMENT
1067 	  unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1068 	  /* Don't increase alignment too much for TLS variables - TLS space
1069 	     is too precious.  */
1070 	  if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1071 	    align = data_align;
1072 #endif
1073 	  if (DECL_INITIAL (decl) != 0
1074 	      /* In LTO we have no errors in program; error_mark_node is used
1075 		 to mark offlined constructors.  */
1076 	      && (in_lto_p || DECL_INITIAL (decl) != error_mark_node))
1077 	    {
1078 	      unsigned int const_align
1079 		= targetm.constant_alignment (DECL_INITIAL (decl), align);
1080 	      /* Don't increase alignment too much for TLS variables - TLS
1081 		 space is too precious.  */
1082 	      if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1083 		align = const_align;
1084 	    }
1085 	}
1086     }
1087 
1088   /* Reset the alignment in case we have made it tighter, so we can benefit
1089      from it in get_pointer_alignment.  */
1090   SET_DECL_ALIGN (decl, align);
1091 }
1092 
1093 /* Return DECL_ALIGN (decl), possibly increased for optimization purposes
1094    beyond what align_variable returned.  */
1095 
1096 static unsigned int
get_variable_align(tree decl)1097 get_variable_align (tree decl)
1098 {
1099   unsigned int align = DECL_ALIGN (decl);
1100 
1101   /* For user aligned vars or static vars align_variable already did
1102      everything.  */
1103   if (DECL_USER_ALIGN (decl) || !TREE_PUBLIC (decl))
1104     return align;
1105 
1106 #ifdef DATA_ABI_ALIGNMENT
1107   if (DECL_THREAD_LOCAL_P (decl))
1108     align = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1109 #endif
1110 
1111   /* For decls that bind to the current definition, align_variable
1112      did also everything, except for not assuming ABI required alignment
1113      of TLS variables.  For other vars, increase the alignment here
1114      as an optimization.  */
1115   if (!decl_binds_to_current_def_p (decl))
1116     {
1117       /* On some machines, it is good to increase alignment sometimes.  */
1118 #ifdef DATA_ALIGNMENT
1119       unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1120       /* Don't increase alignment too much for TLS variables - TLS space
1121          is too precious.  */
1122       if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1123 	align = data_align;
1124 #endif
1125       if (DECL_INITIAL (decl) != 0
1126 	  /* In LTO we have no errors in program; error_mark_node is used
1127 	     to mark offlined constructors.  */
1128 	  && (in_lto_p || DECL_INITIAL (decl) != error_mark_node))
1129 	{
1130 	  unsigned int const_align
1131 	    = targetm.constant_alignment (DECL_INITIAL (decl), align);
1132 	  /* Don't increase alignment too much for TLS variables - TLS space
1133 	     is too precious.  */
1134 	  if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1135 	    align = const_align;
1136 	}
1137     }
1138 
1139   return align;
1140 }
1141 
1142 /* Return the section into which the given VAR_DECL or CONST_DECL
1143    should be placed.  PREFER_NOSWITCH_P is true if a noswitch
1144    section should be used wherever possible.  */
1145 
1146 section *
get_variable_section(tree decl,bool prefer_noswitch_p)1147 get_variable_section (tree decl, bool prefer_noswitch_p)
1148 {
1149   addr_space_t as = ADDR_SPACE_GENERIC;
1150   int reloc;
1151   varpool_node *vnode = varpool_node::get (decl);
1152   if (vnode)
1153     {
1154       vnode = vnode->ultimate_alias_target ();
1155       decl = vnode->decl;
1156     }
1157 
1158   if (TREE_TYPE (decl) != error_mark_node)
1159     as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1160 
1161   /* We need the constructor to figure out reloc flag.  */
1162   if (vnode)
1163     vnode->get_constructor ();
1164 
1165   if (DECL_COMMON (decl))
1166     {
1167       /* If the decl has been given an explicit section name, or it resides
1168 	 in a non-generic address space, then it isn't common, and shouldn't
1169 	 be handled as such.  */
1170       gcc_assert (DECL_SECTION_NAME (decl) == NULL
1171 		  && ADDR_SPACE_GENERIC_P (as));
1172       if (DECL_THREAD_LOCAL_P (decl))
1173 	return tls_comm_section;
1174       else if (TREE_PUBLIC (decl) && bss_initializer_p (decl))
1175 	return comm_section;
1176     }
1177 
1178   if (DECL_INITIAL (decl) == error_mark_node)
1179     reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1180   else if (DECL_INITIAL (decl))
1181     reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1182   else
1183     reloc = 0;
1184 
1185   resolve_unique_section (decl, reloc, flag_data_sections);
1186   if (IN_NAMED_SECTION (decl))
1187     {
1188       section *sect = get_named_section (decl, NULL, reloc);
1189 
1190       if ((sect->common.flags & SECTION_BSS)
1191 	  && !bss_initializer_p (decl, true))
1192 	{
1193 	  error_at (DECL_SOURCE_LOCATION (decl),
1194 		    "only zero initializers are allowed in section %qs",
1195 		    sect->named.name);
1196 	  DECL_INITIAL (decl) = error_mark_node;
1197 	}
1198       return sect;
1199     }
1200 
1201   if (ADDR_SPACE_GENERIC_P (as)
1202       && !DECL_THREAD_LOCAL_P (decl)
1203       && !(prefer_noswitch_p && targetm.have_switchable_bss_sections)
1204       && bss_initializer_p (decl))
1205     {
1206       if (!TREE_PUBLIC (decl)
1207 	  && !((flag_sanitize & SANITIZE_ADDRESS)
1208 	       && asan_protect_global (decl)))
1209 	return lcomm_section;
1210       if (bss_noswitch_section)
1211 	return bss_noswitch_section;
1212     }
1213 
1214   return targetm.asm_out.select_section (decl, reloc,
1215 					 get_variable_align (decl));
1216 }
1217 
1218 /* Return the block into which object_block DECL should be placed.  */
1219 
1220 static struct object_block *
get_block_for_decl(tree decl)1221 get_block_for_decl (tree decl)
1222 {
1223   section *sect;
1224 
1225   if (VAR_P (decl))
1226     {
1227       /* The object must be defined in this translation unit.  */
1228       if (DECL_EXTERNAL (decl))
1229 	return NULL;
1230 
1231       /* There's no point using object blocks for something that is
1232 	 isolated by definition.  */
1233       if (DECL_COMDAT_GROUP (decl))
1234 	return NULL;
1235     }
1236 
1237   /* We can only calculate block offsets if the decl has a known
1238      constant size.  */
1239   if (DECL_SIZE_UNIT (decl) == NULL)
1240     return NULL;
1241   if (!tree_fits_uhwi_p (DECL_SIZE_UNIT (decl)))
1242     return NULL;
1243 
1244   /* Find out which section should contain DECL.  We cannot put it into
1245      an object block if it requires a standalone definition.  */
1246   if (VAR_P (decl))
1247       align_variable (decl, 0);
1248   sect = get_variable_section (decl, true);
1249   if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
1250     return NULL;
1251 
1252   return get_block_for_section (sect);
1253 }
1254 
1255 /* Make sure block symbol SYMBOL is in block BLOCK.  */
1256 
1257 static void
change_symbol_block(rtx symbol,struct object_block * block)1258 change_symbol_block (rtx symbol, struct object_block *block)
1259 {
1260   if (block != SYMBOL_REF_BLOCK (symbol))
1261     {
1262       gcc_assert (SYMBOL_REF_BLOCK_OFFSET (symbol) < 0);
1263       SYMBOL_REF_BLOCK (symbol) = block;
1264     }
1265 }
1266 
1267 /* Return true if it is possible to put DECL in an object_block.  */
1268 
1269 static bool
use_blocks_for_decl_p(tree decl)1270 use_blocks_for_decl_p (tree decl)
1271 {
1272   struct symtab_node *snode;
1273 
1274   /* Only data DECLs can be placed into object blocks.  */
1275   if (!VAR_P (decl) && TREE_CODE (decl) != CONST_DECL)
1276     return false;
1277 
1278   /* DECL_INITIAL (decl) set to decl is a hack used for some decls that
1279      are never used from code directly and we never want object block handling
1280      for those.  */
1281   if (DECL_INITIAL (decl) == decl)
1282     return false;
1283 
1284   /* If this decl is an alias, then we don't want to emit a
1285      definition.  */
1286   if (VAR_P (decl)
1287       && (snode = symtab_node::get (decl)) != NULL
1288       && snode->alias)
1289     return false;
1290 
1291   return targetm.use_blocks_for_decl_p (decl);
1292 }
1293 
1294 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS
1295    until we find an identifier that is not itself a transparent alias.
1296    Modify the alias passed to it by reference (and all aliases on the
1297    way to the ultimate target), such that they do not have to be
1298    followed again, and return the ultimate target of the alias
1299    chain.  */
1300 
1301 static inline tree
ultimate_transparent_alias_target(tree * alias)1302 ultimate_transparent_alias_target (tree *alias)
1303 {
1304   tree target = *alias;
1305 
1306   if (IDENTIFIER_TRANSPARENT_ALIAS (target))
1307     {
1308       gcc_assert (TREE_CHAIN (target));
1309       target = ultimate_transparent_alias_target (&TREE_CHAIN (target));
1310       gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target)
1311 		  && ! TREE_CHAIN (target));
1312       *alias = target;
1313     }
1314 
1315   return target;
1316 }
1317 
1318 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL.  DECL should
1319    have static storage duration.  In other words, it should not be an
1320    automatic variable, including PARM_DECLs.
1321 
1322    There is, however, one exception: this function handles variables
1323    explicitly placed in a particular register by the user.
1324 
1325    This is never called for PARM_DECL nodes.  */
1326 
1327 void
make_decl_rtl(tree decl)1328 make_decl_rtl (tree decl)
1329 {
1330   const char *name = 0;
1331   int reg_number;
1332   tree id;
1333   rtx x;
1334 
1335   /* Check that we are not being given an automatic variable.  */
1336   gcc_assert (TREE_CODE (decl) != PARM_DECL
1337 	      && TREE_CODE (decl) != RESULT_DECL);
1338 
1339   /* A weak alias has TREE_PUBLIC set but not the other bits.  */
1340   gcc_assert (!VAR_P (decl)
1341 	      || TREE_STATIC (decl)
1342 	      || TREE_PUBLIC (decl)
1343 	      || DECL_EXTERNAL (decl)
1344 	      || DECL_REGISTER (decl));
1345 
1346   /* And that we were not given a type or a label.  */
1347   gcc_assert (TREE_CODE (decl) != TYPE_DECL
1348 	      && TREE_CODE (decl) != LABEL_DECL);
1349 
1350   /* For a duplicate declaration, we can be called twice on the
1351      same DECL node.  Don't discard the RTL already made.  */
1352   if (DECL_RTL_SET_P (decl))
1353     {
1354       /* If the old RTL had the wrong mode, fix the mode.  */
1355       x = DECL_RTL (decl);
1356       if (GET_MODE (x) != DECL_MODE (decl))
1357 	SET_DECL_RTL (decl, adjust_address_nv (x, DECL_MODE (decl), 0));
1358 
1359       if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1360 	return;
1361 
1362       /* ??? Another way to do this would be to maintain a hashed
1363 	 table of such critters.  Instead of adding stuff to a DECL
1364 	 to give certain attributes to it, we could use an external
1365 	 hash map from DECL to set of attributes.  */
1366 
1367       /* Let the target reassign the RTL if it wants.
1368 	 This is necessary, for example, when one machine specific
1369 	 decl attribute overrides another.  */
1370       targetm.encode_section_info (decl, DECL_RTL (decl), false);
1371 
1372       /* If the symbol has a SYMBOL_REF_BLOCK field, update it based
1373 	 on the new decl information.  */
1374       if (MEM_P (x)
1375 	  && GET_CODE (XEXP (x, 0)) == SYMBOL_REF
1376 	  && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (x, 0)))
1377 	change_symbol_block (XEXP (x, 0), get_block_for_decl (decl));
1378 
1379       return;
1380     }
1381 
1382   /* If this variable belongs to the global constant pool, retrieve the
1383      pre-computed RTL or recompute it in LTO mode.  */
1384   if (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
1385     {
1386       SET_DECL_RTL (decl, output_constant_def (DECL_INITIAL (decl), 1));
1387       return;
1388     }
1389 
1390   id = DECL_ASSEMBLER_NAME (decl);
1391   name = IDENTIFIER_POINTER (id);
1392 
1393   if (name[0] != '*' && TREE_CODE (decl) != FUNCTION_DECL
1394       && DECL_REGISTER (decl))
1395     {
1396       error ("register name not specified for %q+D", decl);
1397     }
1398   else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1399     {
1400       const char *asmspec = name+1;
1401       machine_mode mode = DECL_MODE (decl);
1402       reg_number = decode_reg_name (asmspec);
1403       /* First detect errors in declaring global registers.  */
1404       if (reg_number == -1)
1405 	error ("register name not specified for %q+D", decl);
1406       else if (reg_number < 0)
1407 	error ("invalid register name for %q+D", decl);
1408       else if (mode == BLKmode)
1409 	error ("data type of %q+D isn%'t suitable for a register",
1410 	       decl);
1411       else if (!in_hard_reg_set_p (accessible_reg_set, mode, reg_number))
1412 	error ("the register specified for %q+D cannot be accessed"
1413 	       " by the current target", decl);
1414       else if (!in_hard_reg_set_p (operand_reg_set, mode, reg_number))
1415 	error ("the register specified for %q+D is not general enough"
1416 	       " to be used as a register variable", decl);
1417       else if (!targetm.hard_regno_mode_ok (reg_number, mode))
1418 	error ("register specified for %q+D isn%'t suitable for data type",
1419                decl);
1420       /* Now handle properly declared static register variables.  */
1421       else
1422 	{
1423 	  int nregs;
1424 
1425 	  if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
1426 	    {
1427 	      DECL_INITIAL (decl) = 0;
1428 	      error ("global register variable has initial value");
1429 	    }
1430 	  if (TREE_THIS_VOLATILE (decl))
1431 	    warning (OPT_Wvolatile_register_var,
1432 		     "optimization may eliminate reads and/or "
1433 		     "writes to register variables");
1434 
1435 	  /* If the user specified one of the eliminables registers here,
1436 	     e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
1437 	     confused with that register and be eliminated.  This usage is
1438 	     somewhat suspect...  */
1439 
1440 	  SET_DECL_RTL (decl, gen_raw_REG (mode, reg_number));
1441 	  ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
1442 	  REG_USERVAR_P (DECL_RTL (decl)) = 1;
1443 
1444 	  if (TREE_STATIC (decl))
1445 	    {
1446 	      /* Make this register global, so not usable for anything
1447 		 else.  */
1448 #ifdef ASM_DECLARE_REGISTER_GLOBAL
1449 	      name = IDENTIFIER_POINTER (DECL_NAME (decl));
1450 	      ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
1451 #endif
1452 	      nregs = hard_regno_nregs (reg_number, mode);
1453 	      while (nregs > 0)
1454 		globalize_reg (decl, reg_number + --nregs);
1455 	    }
1456 
1457 	  /* As a register variable, it has no section.  */
1458 	  return;
1459 	}
1460       /* Avoid internal errors from invalid register
1461 	 specifications.  */
1462       SET_DECL_ASSEMBLER_NAME (decl, NULL_TREE);
1463       DECL_HARD_REGISTER (decl) = 0;
1464       /* Also avoid SSA inconsistencies by pretending this is an external
1465 	 decl now.  */
1466       DECL_EXTERNAL (decl) = 1;
1467       return;
1468     }
1469   /* Now handle ordinary static variables and functions (in memory).
1470      Also handle vars declared register invalidly.  */
1471   else if (name[0] == '*')
1472   {
1473 #ifdef REGISTER_PREFIX
1474     if (strlen (REGISTER_PREFIX) != 0)
1475       {
1476 	reg_number = decode_reg_name (name);
1477 	if (reg_number >= 0 || reg_number == -3)
1478 	  error ("register name given for non-register variable %q+D", decl);
1479       }
1480 #endif
1481   }
1482 
1483   /* Specifying a section attribute on a variable forces it into a
1484      non-.bss section, and thus it cannot be common.  */
1485   /* FIXME: In general this code should not be necessary because
1486      visibility pass is doing the same work.  But notice_global_symbol
1487      is called early and it needs to make DECL_RTL to get the name.
1488      we take care of recomputing the DECL_RTL after visibility is changed.  */
1489   if (VAR_P (decl)
1490       && (TREE_STATIC (decl) || DECL_EXTERNAL (decl))
1491       && DECL_SECTION_NAME (decl) != NULL
1492       && DECL_INITIAL (decl) == NULL_TREE
1493       && DECL_COMMON (decl))
1494     DECL_COMMON (decl) = 0;
1495 
1496   /* Variables can't be both common and weak.  */
1497   if (VAR_P (decl) && DECL_WEAK (decl))
1498     DECL_COMMON (decl) = 0;
1499 
1500   if (use_object_blocks_p () && use_blocks_for_decl_p (decl))
1501     x = create_block_symbol (name, get_block_for_decl (decl), -1);
1502   else
1503     {
1504       machine_mode address_mode = Pmode;
1505       if (TREE_TYPE (decl) != error_mark_node)
1506 	{
1507 	  addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1508 	  address_mode = targetm.addr_space.address_mode (as);
1509 	}
1510       x = gen_rtx_SYMBOL_REF (address_mode, name);
1511     }
1512   SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
1513   SET_SYMBOL_REF_DECL (x, decl);
1514 
1515   x = gen_rtx_MEM (DECL_MODE (decl), x);
1516   if (TREE_CODE (decl) != FUNCTION_DECL)
1517     set_mem_attributes (x, decl, 1);
1518   SET_DECL_RTL (decl, x);
1519 
1520   /* Optionally set flags or add text to the name to record information
1521      such as that it is a function name.
1522      If the name is changed, the macro ASM_OUTPUT_LABELREF
1523      will have to know how to strip this information.  */
1524   targetm.encode_section_info (decl, DECL_RTL (decl), true);
1525 }
1526 
1527 /* Like make_decl_rtl, but inhibit creation of new alias sets when
1528    calling make_decl_rtl.  Also, reset DECL_RTL before returning the
1529    rtl.  */
1530 
1531 rtx
make_decl_rtl_for_debug(tree decl)1532 make_decl_rtl_for_debug (tree decl)
1533 {
1534   unsigned int save_aliasing_flag;
1535   rtx rtl;
1536 
1537   if (DECL_RTL_SET_P (decl))
1538     return DECL_RTL (decl);
1539 
1540   /* Kludge alert!  Somewhere down the call chain, make_decl_rtl will
1541      call new_alias_set.  If running with -fcompare-debug, sometimes
1542      we do not want to create alias sets that will throw the alias
1543      numbers off in the comparison dumps.  So... clearing
1544      flag_strict_aliasing will keep new_alias_set() from creating a
1545      new set.  */
1546   save_aliasing_flag = flag_strict_aliasing;
1547   flag_strict_aliasing = 0;
1548 
1549   rtl = DECL_RTL (decl);
1550   /* Reset DECL_RTL back, as various parts of the compiler expects
1551      DECL_RTL set meaning it is actually going to be output.  */
1552   SET_DECL_RTL (decl, NULL);
1553 
1554   flag_strict_aliasing = save_aliasing_flag;
1555   return rtl;
1556 }
1557 
1558 /* Output a string of literal assembler code
1559    for an `asm' keyword used between functions.  */
1560 
1561 void
assemble_asm(tree string)1562 assemble_asm (tree string)
1563 {
1564   const char *p;
1565   app_enable ();
1566 
1567   if (TREE_CODE (string) == ADDR_EXPR)
1568     string = TREE_OPERAND (string, 0);
1569 
1570   p = TREE_STRING_POINTER (string);
1571   fprintf (asm_out_file, "%s%s\n", p[0] == '\t' ? "" : "\t", p);
1572 }
1573 
1574 /* Write the address of the entity given by SYMBOL to SEC.  */
1575 void
assemble_addr_to_section(rtx symbol,section * sec)1576 assemble_addr_to_section (rtx symbol, section *sec)
1577 {
1578   switch_to_section (sec);
1579   assemble_align (POINTER_SIZE);
1580   assemble_integer (symbol, POINTER_SIZE_UNITS, POINTER_SIZE, 1);
1581 }
1582 
1583 /* Return the numbered .ctors.N (if CONSTRUCTOR_P) or .dtors.N (if
1584    not) section for PRIORITY.  */
1585 section *
get_cdtor_priority_section(int priority,bool constructor_p)1586 get_cdtor_priority_section (int priority, bool constructor_p)
1587 {
1588   /* Buffer conservatively large enough for the full range of a 32-bit
1589      int plus the text below.  */
1590   char buf[18];
1591 
1592   /* ??? This only works reliably with the GNU linker.  */
1593   sprintf (buf, "%s.%.5u",
1594 	   constructor_p ? ".ctors" : ".dtors",
1595 	   /* Invert the numbering so the linker puts us in the proper
1596 	      order; constructors are run from right to left, and the
1597 	      linker sorts in increasing order.  */
1598 	   MAX_INIT_PRIORITY - priority);
1599   return get_section (buf, SECTION_WRITE, NULL);
1600 }
1601 
1602 void
default_named_section_asm_out_destructor(rtx symbol,int priority)1603 default_named_section_asm_out_destructor (rtx symbol, int priority)
1604 {
1605   section *sec;
1606 
1607   if (priority != DEFAULT_INIT_PRIORITY)
1608     sec = get_cdtor_priority_section (priority,
1609 				      /*constructor_p=*/false);
1610   else
1611     sec = get_section (".dtors", SECTION_WRITE, NULL);
1612 
1613   assemble_addr_to_section (symbol, sec);
1614 }
1615 
1616 #ifdef DTORS_SECTION_ASM_OP
1617 void
default_dtor_section_asm_out_destructor(rtx symbol,int priority ATTRIBUTE_UNUSED)1618 default_dtor_section_asm_out_destructor (rtx symbol,
1619 					 int priority ATTRIBUTE_UNUSED)
1620 {
1621   assemble_addr_to_section (symbol, dtors_section);
1622 }
1623 #endif
1624 
1625 void
default_named_section_asm_out_constructor(rtx symbol,int priority)1626 default_named_section_asm_out_constructor (rtx symbol, int priority)
1627 {
1628   section *sec;
1629 
1630   if (priority != DEFAULT_INIT_PRIORITY)
1631     sec = get_cdtor_priority_section (priority,
1632 				      /*constructor_p=*/true);
1633   else
1634     sec = get_section (".ctors", SECTION_WRITE, NULL);
1635 
1636   assemble_addr_to_section (symbol, sec);
1637 }
1638 
1639 #ifdef CTORS_SECTION_ASM_OP
1640 void
default_ctor_section_asm_out_constructor(rtx symbol,int priority ATTRIBUTE_UNUSED)1641 default_ctor_section_asm_out_constructor (rtx symbol,
1642 					  int priority ATTRIBUTE_UNUSED)
1643 {
1644   assemble_addr_to_section (symbol, ctors_section);
1645 }
1646 #endif
1647 
1648 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1649    a nonzero value if the constant pool should be output before the
1650    start of the function, or a zero value if the pool should output
1651    after the end of the function.  The default is to put it before the
1652    start.  */
1653 
1654 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1655 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1656 #endif
1657 
1658 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1659    to be output to assembler.
1660    Set first_global_object_name and weak_global_object_name as appropriate.  */
1661 
1662 void
notice_global_symbol(tree decl)1663 notice_global_symbol (tree decl)
1664 {
1665   const char **t = &first_global_object_name;
1666 
1667   if (first_global_object_name
1668       || !TREE_PUBLIC (decl)
1669       || DECL_EXTERNAL (decl)
1670       || !DECL_NAME (decl)
1671       || (VAR_P (decl) && DECL_HARD_REGISTER (decl))
1672       || (TREE_CODE (decl) != FUNCTION_DECL
1673 	  && (!VAR_P (decl)
1674 	      || (DECL_COMMON (decl)
1675 		  && (DECL_INITIAL (decl) == 0
1676 		      || DECL_INITIAL (decl) == error_mark_node)))))
1677     return;
1678 
1679   /* We win when global object is found, but it is useful to know about weak
1680      symbol as well so we can produce nicer unique names.  */
1681   if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl) || flag_shlib)
1682     t = &weak_global_object_name;
1683 
1684   if (!*t)
1685     {
1686       tree id = DECL_ASSEMBLER_NAME (decl);
1687       ultimate_transparent_alias_target (&id);
1688       *t = ggc_strdup (targetm.strip_name_encoding (IDENTIFIER_POINTER (id)));
1689     }
1690 }
1691 
1692 /* If not using flag_reorder_blocks_and_partition, decide early whether the
1693    current function goes into the cold section, so that targets can use
1694    current_function_section during RTL expansion.  DECL describes the
1695    function.  */
1696 
1697 void
decide_function_section(tree decl)1698 decide_function_section (tree decl)
1699 {
1700   first_function_block_is_cold = false;
1701 
1702  if (DECL_SECTION_NAME (decl))
1703     {
1704       struct cgraph_node *node = cgraph_node::get (current_function_decl);
1705       /* Calls to function_section rely on first_function_block_is_cold
1706 	 being accurate.  */
1707       first_function_block_is_cold = (node
1708 				      && node->frequency
1709 				      == NODE_FREQUENCY_UNLIKELY_EXECUTED);
1710     }
1711 
1712   in_cold_section_p = first_function_block_is_cold;
1713 }
1714 
1715 /* Get the function's name, as described by its RTL.  This may be
1716    different from the DECL_NAME name used in the source file.  */
1717 const char *
get_fnname_from_decl(tree decl)1718 get_fnname_from_decl (tree decl)
1719 {
1720   rtx x = DECL_RTL (decl);
1721   gcc_assert (MEM_P (x));
1722   x = XEXP (x, 0);
1723   gcc_assert (GET_CODE (x) == SYMBOL_REF);
1724   return XSTR (x, 0);
1725 }
1726 
1727 /* Output assembler code for the constant pool of a function and associated
1728    with defining the name of the function.  DECL describes the function.
1729    NAME is the function's name.  For the constant pool, we use the current
1730    constant pool data.  */
1731 
1732 void
assemble_start_function(tree decl,const char * fnname)1733 assemble_start_function (tree decl, const char *fnname)
1734 {
1735   int align;
1736   char tmp_label[100];
1737   bool hot_label_written = false;
1738 
1739   if (crtl->has_bb_partition)
1740     {
1741       ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTB", const_labelno);
1742       crtl->subsections.hot_section_label = ggc_strdup (tmp_label);
1743       ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDB", const_labelno);
1744       crtl->subsections.cold_section_label = ggc_strdup (tmp_label);
1745       ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTE", const_labelno);
1746       crtl->subsections.hot_section_end_label = ggc_strdup (tmp_label);
1747       ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDE", const_labelno);
1748       crtl->subsections.cold_section_end_label = ggc_strdup (tmp_label);
1749       const_labelno++;
1750       cold_function_name = NULL_TREE;
1751     }
1752   else
1753     {
1754       crtl->subsections.hot_section_label = NULL;
1755       crtl->subsections.cold_section_label = NULL;
1756       crtl->subsections.hot_section_end_label = NULL;
1757       crtl->subsections.cold_section_end_label = NULL;
1758     }
1759 
1760   /* The following code does not need preprocessing in the assembler.  */
1761 
1762   app_disable ();
1763 
1764   if (CONSTANT_POOL_BEFORE_FUNCTION)
1765     output_constant_pool (fnname, decl);
1766 
1767   align = symtab_node::get (decl)->definition_alignment ();
1768 
1769   /* Make sure the not and cold text (code) sections are properly
1770      aligned.  This is necessary here in the case where the function
1771      has both hot and cold sections, because we don't want to re-set
1772      the alignment when the section switch happens mid-function.  */
1773 
1774   if (crtl->has_bb_partition)
1775     {
1776       first_function_block_is_cold = false;
1777 
1778       switch_to_section (unlikely_text_section ());
1779       assemble_align (align);
1780       ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_label);
1781 
1782       /* When the function starts with a cold section, we need to explicitly
1783 	 align the hot section and write out the hot section label.
1784 	 But if the current function is a thunk, we do not have a CFG.  */
1785       if (!cfun->is_thunk
1786 	  && BB_PARTITION (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) == BB_COLD_PARTITION)
1787 	{
1788 	  switch_to_section (text_section);
1789 	  assemble_align (align);
1790 	  ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1791 	  hot_label_written = true;
1792 	  first_function_block_is_cold = true;
1793 	}
1794       in_cold_section_p = first_function_block_is_cold;
1795     }
1796 
1797 
1798   /* Switch to the correct text section for the start of the function.  */
1799 
1800   switch_to_section (function_section (decl));
1801   if (crtl->has_bb_partition && !hot_label_written)
1802     ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1803 
1804   /* Tell assembler to move to target machine's alignment for functions.  */
1805   align = floor_log2 (align / BITS_PER_UNIT);
1806   if (align > 0)
1807     {
1808       ASM_OUTPUT_ALIGN (asm_out_file, align);
1809     }
1810 
1811   /* Handle a user-specified function alignment.
1812      Note that we still need to align to DECL_ALIGN, as above,
1813      because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all.  */
1814   if (! DECL_USER_ALIGN (decl)
1815       && align_functions.levels[0].log > align
1816       && optimize_function_for_speed_p (cfun))
1817     {
1818 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1819       int align_log = align_functions.levels[0].log;
1820 #endif
1821       int max_skip = align_functions.levels[0].maxskip;
1822       if (flag_limit_function_alignment && crtl->max_insn_address > 0
1823 	  && max_skip >= crtl->max_insn_address)
1824 	max_skip = crtl->max_insn_address - 1;
1825 
1826 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1827       ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file, align_log, max_skip);
1828       if (max_skip == align_functions.levels[0].maxskip)
1829 	ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1830 				   align_functions.levels[1].log,
1831 				   align_functions.levels[1].maxskip);
1832 #else
1833       ASM_OUTPUT_ALIGN (asm_out_file, align_functions.levels[0].log);
1834 #endif
1835     }
1836 
1837 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1838   ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1839 #endif
1840 
1841   if (!DECL_IGNORED_P (decl))
1842     (*debug_hooks->begin_function) (decl);
1843 
1844   /* Make function name accessible from other files, if appropriate.  */
1845 
1846   if (TREE_PUBLIC (decl))
1847     {
1848       notice_global_symbol (decl);
1849 
1850       globalize_decl (decl);
1851 
1852       maybe_assemble_visibility (decl);
1853     }
1854 
1855   if (DECL_PRESERVE_P (decl))
1856     targetm.asm_out.mark_decl_preserved (fnname);
1857 
1858   unsigned HOST_WIDE_INT patch_area_size = function_entry_patch_area_size;
1859   unsigned HOST_WIDE_INT patch_area_entry = function_entry_patch_area_start;
1860 
1861   tree patchable_function_entry_attr
1862     = lookup_attribute ("patchable_function_entry", DECL_ATTRIBUTES (decl));
1863   if (patchable_function_entry_attr)
1864     {
1865       tree pp_val = TREE_VALUE (patchable_function_entry_attr);
1866       tree patchable_function_entry_value1 = TREE_VALUE (pp_val);
1867 
1868       patch_area_size = tree_to_uhwi (patchable_function_entry_value1);
1869       patch_area_entry = 0;
1870       if (TREE_CHAIN (pp_val) != NULL_TREE)
1871 	{
1872 	  tree patchable_function_entry_value2
1873 	    = TREE_VALUE (TREE_CHAIN (pp_val));
1874 	  patch_area_entry = tree_to_uhwi (patchable_function_entry_value2);
1875 	}
1876     }
1877 
1878   if (patch_area_entry > patch_area_size)
1879     {
1880       if (patch_area_size > 0)
1881 	warning (OPT_Wattributes, "patchable function entry > size");
1882       patch_area_entry = 0;
1883     }
1884 
1885   /* Emit the patching area before the entry label, if any.  */
1886   if (patch_area_entry > 0)
1887     targetm.asm_out.print_patchable_function_entry (asm_out_file,
1888 						    patch_area_entry, true);
1889 
1890   /* Do any machine/system dependent processing of the function name.  */
1891 #ifdef ASM_DECLARE_FUNCTION_NAME
1892   ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1893 #else
1894   /* Standard thing is just output label for the function.  */
1895   ASM_OUTPUT_FUNCTION_LABEL (asm_out_file, fnname, current_function_decl);
1896 #endif /* ASM_DECLARE_FUNCTION_NAME */
1897 
1898   /* And the area after the label.  Record it if we haven't done so yet.  */
1899   if (patch_area_size > patch_area_entry)
1900     targetm.asm_out.print_patchable_function_entry (asm_out_file,
1901 						    patch_area_size
1902 						    - patch_area_entry,
1903 						    patch_area_entry == 0);
1904 
1905   if (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (decl)))
1906     saw_no_split_stack = true;
1907 }
1908 
1909 /* Output assembler code associated with defining the size of the
1910    function.  DECL describes the function.  NAME is the function's name.  */
1911 
1912 void
assemble_end_function(tree decl,const char * fnname ATTRIBUTE_UNUSED)1913 assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED)
1914 {
1915 #ifdef ASM_DECLARE_FUNCTION_SIZE
1916   /* We could have switched section in the middle of the function.  */
1917   if (crtl->has_bb_partition)
1918     switch_to_section (function_section (decl));
1919   ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1920 #endif
1921   if (! CONSTANT_POOL_BEFORE_FUNCTION)
1922     {
1923       output_constant_pool (fnname, decl);
1924       switch_to_section (function_section (decl)); /* need to switch back */
1925     }
1926   /* Output labels for end of hot/cold text sections (to be used by
1927      debug info.)  */
1928   if (crtl->has_bb_partition)
1929     {
1930       section *save_text_section;
1931 
1932       save_text_section = in_section;
1933       switch_to_section (unlikely_text_section ());
1934 #ifdef ASM_DECLARE_COLD_FUNCTION_SIZE
1935       if (cold_function_name != NULL_TREE)
1936 	ASM_DECLARE_COLD_FUNCTION_SIZE (asm_out_file,
1937 					IDENTIFIER_POINTER (cold_function_name),
1938 					decl);
1939 #endif
1940       ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label);
1941       if (first_function_block_is_cold)
1942 	switch_to_section (text_section);
1943       else
1944 	switch_to_section (function_section (decl));
1945       ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label);
1946       switch_to_section (save_text_section);
1947     }
1948 }
1949 
1950 /* Assemble code to leave SIZE bytes of zeros.  */
1951 
1952 void
assemble_zeros(unsigned HOST_WIDE_INT size)1953 assemble_zeros (unsigned HOST_WIDE_INT size)
1954 {
1955   /* Do no output if -fsyntax-only.  */
1956   if (flag_syntax_only)
1957     return;
1958 
1959 #ifdef ASM_NO_SKIP_IN_TEXT
1960   /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1961      so we must output 0s explicitly in the text section.  */
1962   if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0)
1963     {
1964       unsigned HOST_WIDE_INT i;
1965       for (i = 0; i < size; i++)
1966 	assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1967     }
1968   else
1969 #endif
1970     if (size > 0)
1971       ASM_OUTPUT_SKIP (asm_out_file, size);
1972 }
1973 
1974 /* Assemble an alignment pseudo op for an ALIGN-bit boundary.  */
1975 
1976 void
assemble_align(unsigned int align)1977 assemble_align (unsigned int align)
1978 {
1979   if (align > BITS_PER_UNIT)
1980     {
1981       ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1982     }
1983 }
1984 
1985 /* Assemble a string constant with the specified C string as contents.  */
1986 
1987 void
assemble_string(const char * p,int size)1988 assemble_string (const char *p, int size)
1989 {
1990   int pos = 0;
1991   int maximum = 2000;
1992 
1993   /* If the string is very long, split it up.  */
1994 
1995   while (pos < size)
1996     {
1997       int thissize = size - pos;
1998       if (thissize > maximum)
1999 	thissize = maximum;
2000 
2001       ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
2002 
2003       pos += thissize;
2004       p += thissize;
2005     }
2006 }
2007 
2008 
2009 /* A noswitch_section_callback for lcomm_section.  */
2010 
2011 static bool
emit_local(tree decl ATTRIBUTE_UNUSED,const char * name ATTRIBUTE_UNUSED,unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)2012 emit_local (tree decl ATTRIBUTE_UNUSED,
2013 	    const char *name ATTRIBUTE_UNUSED,
2014 	    unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2015 	    unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2016 {
2017 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
2018   unsigned int align = symtab_node::get (decl)->definition_alignment ();
2019   ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name,
2020 				 size, align);
2021   return true;
2022 #elif defined ASM_OUTPUT_ALIGNED_LOCAL
2023   unsigned int align = symtab_node::get (decl)->definition_alignment ();
2024   ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, align);
2025   return true;
2026 #else
2027   ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2028   return false;
2029 #endif
2030 }
2031 
2032 /* A noswitch_section_callback for bss_noswitch_section.  */
2033 
2034 #if defined ASM_OUTPUT_ALIGNED_BSS
2035 static bool
emit_bss(tree decl ATTRIBUTE_UNUSED,const char * name ATTRIBUTE_UNUSED,unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)2036 emit_bss (tree decl ATTRIBUTE_UNUSED,
2037 	  const char *name ATTRIBUTE_UNUSED,
2038 	  unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2039 	  unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2040 {
2041   ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size,
2042 			  get_variable_align (decl));
2043   return true;
2044 }
2045 #endif
2046 
2047 /* A noswitch_section_callback for comm_section.  */
2048 
2049 static bool
emit_common(tree decl ATTRIBUTE_UNUSED,const char * name ATTRIBUTE_UNUSED,unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)2050 emit_common (tree decl ATTRIBUTE_UNUSED,
2051 	     const char *name ATTRIBUTE_UNUSED,
2052 	     unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2053 	     unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2054 {
2055 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
2056   ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name,
2057 				  size, get_variable_align (decl));
2058   return true;
2059 #elif defined ASM_OUTPUT_ALIGNED_COMMON
2060   ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size,
2061 			     get_variable_align (decl));
2062   return true;
2063 #else
2064   ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
2065   return false;
2066 #endif
2067 }
2068 
2069 /* A noswitch_section_callback for tls_comm_section.  */
2070 
2071 static bool
emit_tls_common(tree decl ATTRIBUTE_UNUSED,const char * name ATTRIBUTE_UNUSED,unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)2072 emit_tls_common (tree decl ATTRIBUTE_UNUSED,
2073 		 const char *name ATTRIBUTE_UNUSED,
2074 		 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2075 		 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2076 {
2077 #ifdef ASM_OUTPUT_TLS_COMMON
2078   ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size);
2079   return true;
2080 #else
2081   sorry ("thread-local COMMON data not implemented");
2082   return true;
2083 #endif
2084 }
2085 
2086 /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT.
2087    NAME is the name of DECL's SYMBOL_REF.  */
2088 
2089 static void
assemble_noswitch_variable(tree decl,const char * name,section * sect,unsigned int align)2090 assemble_noswitch_variable (tree decl, const char *name, section *sect,
2091 			    unsigned int align)
2092 {
2093   unsigned HOST_WIDE_INT size, rounded;
2094 
2095   size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2096   rounded = size;
2097 
2098   if ((flag_sanitize & SANITIZE_ADDRESS) && asan_protect_global (decl))
2099     size += asan_red_zone_size (size);
2100 
2101   /* Don't allocate zero bytes of common,
2102      since that means "undefined external" in the linker.  */
2103   if (size == 0)
2104     rounded = 1;
2105 
2106   /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2107      so that each uninitialized object starts on such a boundary.  */
2108   rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
2109   rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2110 	     * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2111 
2112   if (!sect->noswitch.callback (decl, name, size, rounded)
2113       && (unsigned HOST_WIDE_INT) (align / BITS_PER_UNIT) > rounded)
2114     error ("requested alignment for %q+D is greater than "
2115 	   "implemented alignment of %wu", decl, rounded);
2116 }
2117 
2118 /* A subroutine of assemble_variable.  Output the label and contents of
2119    DECL, whose address is a SYMBOL_REF with name NAME.  DONT_OUTPUT_DATA
2120    is as for assemble_variable.  */
2121 
2122 static void
assemble_variable_contents(tree decl,const char * name,bool dont_output_data,bool merge_strings)2123 assemble_variable_contents (tree decl, const char *name,
2124 			    bool dont_output_data, bool merge_strings)
2125 {
2126   /* Do any machine/system dependent processing of the object.  */
2127 #ifdef ASM_DECLARE_OBJECT_NAME
2128   last_assemble_variable_decl = decl;
2129   ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
2130 #else
2131   /* Standard thing is just output label for the object.  */
2132   ASM_OUTPUT_LABEL (asm_out_file, name);
2133 #endif /* ASM_DECLARE_OBJECT_NAME */
2134 
2135   if (!dont_output_data)
2136     {
2137       /* Caller is supposed to use varpool_get_constructor when it wants
2138 	 to output the body.  */
2139       gcc_assert (!in_lto_p || DECL_INITIAL (decl) != error_mark_node);
2140       if (DECL_INITIAL (decl)
2141 	  && DECL_INITIAL (decl) != error_mark_node
2142 	  && !initializer_zerop (DECL_INITIAL (decl)))
2143 	/* Output the actual data.  */
2144 	output_constant (DECL_INITIAL (decl),
2145 			 tree_to_uhwi (DECL_SIZE_UNIT (decl)),
2146 			 get_variable_align (decl),
2147 			 false, merge_strings);
2148       else
2149 	/* Leave space for it.  */
2150 	assemble_zeros (tree_to_uhwi (DECL_SIZE_UNIT (decl)));
2151       targetm.asm_out.decl_end ();
2152     }
2153 }
2154 
2155 /* Write out assembly for the variable DECL, which is not defined in
2156    the current translation unit.  */
2157 void
assemble_undefined_decl(tree decl)2158 assemble_undefined_decl (tree decl)
2159 {
2160   const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
2161   targetm.asm_out.assemble_undefined_decl (asm_out_file, name, decl);
2162 }
2163 
2164 /* Assemble everything that is needed for a variable or function declaration.
2165    Not used for automatic variables, and not used for function definitions.
2166    Should not be called for variables of incomplete structure type.
2167 
2168    TOP_LEVEL is nonzero if this variable has file scope.
2169    AT_END is nonzero if this is the special handling, at end of compilation,
2170    to define things that have had only tentative definitions.
2171    DONT_OUTPUT_DATA if nonzero means don't actually output the
2172    initial value (that will be done by the caller).  */
2173 
2174 void
assemble_variable(tree decl,int top_level ATTRIBUTE_UNUSED,int at_end ATTRIBUTE_UNUSED,int dont_output_data)2175 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
2176 		   int at_end ATTRIBUTE_UNUSED, int dont_output_data)
2177 {
2178   const char *name;
2179   rtx decl_rtl, symbol;
2180   section *sect;
2181   unsigned int align;
2182   bool asan_protected = false;
2183 
2184   /* This function is supposed to handle VARIABLES.  Ensure we have one.  */
2185   gcc_assert (VAR_P (decl));
2186 
2187   /* Emulated TLS had better not get this far.  */
2188   gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl));
2189 
2190   last_assemble_variable_decl = 0;
2191 
2192   /* Normally no need to say anything here for external references,
2193      since assemble_external is called by the language-specific code
2194      when a declaration is first seen.  */
2195 
2196   if (DECL_EXTERNAL (decl))
2197     return;
2198 
2199   /* Do nothing for global register variables.  */
2200   if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
2201     {
2202       TREE_ASM_WRITTEN (decl) = 1;
2203       return;
2204     }
2205 
2206   /* If type was incomplete when the variable was declared,
2207      see if it is complete now.  */
2208 
2209   if (DECL_SIZE (decl) == 0)
2210     layout_decl (decl, 0);
2211 
2212   /* Still incomplete => don't allocate it; treat the tentative defn
2213      (which is what it must have been) as an `extern' reference.  */
2214 
2215   if (!dont_output_data && DECL_SIZE (decl) == 0)
2216     {
2217       error ("storage size of %q+D isn%'t known", decl);
2218       TREE_ASM_WRITTEN (decl) = 1;
2219       return;
2220     }
2221 
2222   /* The first declaration of a variable that comes through this function
2223      decides whether it is global (in C, has external linkage)
2224      or local (in C, has internal linkage).  So do nothing more
2225      if this function has already run.  */
2226 
2227   if (TREE_ASM_WRITTEN (decl))
2228     return;
2229 
2230   /* Make sure targetm.encode_section_info is invoked before we set
2231      ASM_WRITTEN.  */
2232   decl_rtl = DECL_RTL (decl);
2233 
2234   TREE_ASM_WRITTEN (decl) = 1;
2235 
2236   /* Do no output if -fsyntax-only.  */
2237   if (flag_syntax_only)
2238     return;
2239 
2240   if (! dont_output_data
2241       && ! valid_constant_size_p (DECL_SIZE_UNIT (decl)))
2242     {
2243       error ("size of variable %q+D is too large", decl);
2244       return;
2245     }
2246 
2247   gcc_assert (MEM_P (decl_rtl));
2248   gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF);
2249   symbol = XEXP (decl_rtl, 0);
2250 
2251   /* If this symbol belongs to the tree constant pool, output the constant
2252      if it hasn't already been written.  */
2253   if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
2254     {
2255       tree decl = SYMBOL_REF_DECL (symbol);
2256       if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
2257 	output_constant_def_contents (symbol);
2258       return;
2259     }
2260 
2261   app_disable ();
2262 
2263   name = XSTR (symbol, 0);
2264   if (TREE_PUBLIC (decl) && DECL_NAME (decl))
2265     notice_global_symbol (decl);
2266 
2267   /* Compute the alignment of this data.  */
2268 
2269   align_variable (decl, dont_output_data);
2270 
2271   if ((flag_sanitize & SANITIZE_ADDRESS)
2272       && asan_protect_global (decl))
2273     {
2274       asan_protected = true;
2275       SET_DECL_ALIGN (decl, MAX (DECL_ALIGN (decl),
2276 				 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT));
2277     }
2278 
2279   set_mem_align (decl_rtl, DECL_ALIGN (decl));
2280 
2281   align = get_variable_align (decl);
2282 
2283   if (TREE_PUBLIC (decl))
2284     maybe_assemble_visibility (decl);
2285 
2286   if (DECL_PRESERVE_P (decl))
2287     targetm.asm_out.mark_decl_preserved (name);
2288 
2289   /* First make the assembler name(s) global if appropriate.  */
2290   sect = get_variable_section (decl, false);
2291   if (TREE_PUBLIC (decl)
2292       && (sect->common.flags & SECTION_COMMON) == 0)
2293     globalize_decl (decl);
2294 
2295   /* Output any data that we will need to use the address of.  */
2296   if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
2297     output_addressed_constants (DECL_INITIAL (decl));
2298 
2299   /* dbxout.c needs to know this.  */
2300   if (sect && (sect->common.flags & SECTION_CODE) != 0)
2301     DECL_IN_TEXT_SECTION (decl) = 1;
2302 
2303   /* If the decl is part of an object_block, make sure that the decl
2304      has been positioned within its block, but do not write out its
2305      definition yet.  output_object_blocks will do that later.  */
2306   if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
2307     {
2308       gcc_assert (!dont_output_data);
2309       place_block_symbol (symbol);
2310     }
2311   else if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
2312     assemble_noswitch_variable (decl, name, sect, align);
2313   else
2314     {
2315       /* Special-case handling of vtv comdat sections.  */
2316       if (sect->named.name
2317 	  && (strcmp (sect->named.name, ".vtable_map_vars") == 0))
2318 	handle_vtv_comdat_section (sect, decl);
2319       else
2320 	switch_to_section (sect);
2321       if (align > BITS_PER_UNIT)
2322 	ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2323       assemble_variable_contents (decl, name, dont_output_data,
2324 				  (sect->common.flags & SECTION_MERGE)
2325 				  && (sect->common.flags & SECTION_STRINGS));
2326       if (asan_protected)
2327 	{
2328 	  unsigned HOST_WIDE_INT int size
2329 	    = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2330 	  assemble_zeros (asan_red_zone_size (size));
2331 	}
2332     }
2333 }
2334 
2335 
2336 /* Given a function declaration (FN_DECL), this function assembles the
2337    function into the .preinit_array section.  */
2338 
2339 void
assemble_vtv_preinit_initializer(tree fn_decl)2340 assemble_vtv_preinit_initializer (tree fn_decl)
2341 {
2342   section *sect;
2343   unsigned flags = SECTION_WRITE;
2344   rtx symbol = XEXP (DECL_RTL (fn_decl), 0);
2345 
2346   flags |= SECTION_NOTYPE;
2347   sect = get_section (".preinit_array", flags, fn_decl);
2348   switch_to_section (sect);
2349   assemble_addr_to_section (symbol, sect);
2350 }
2351 
2352 /* Return 1 if type TYPE contains any pointers.  */
2353 
2354 static int
contains_pointers_p(tree type)2355 contains_pointers_p (tree type)
2356 {
2357   switch (TREE_CODE (type))
2358     {
2359     case POINTER_TYPE:
2360     case REFERENCE_TYPE:
2361       /* I'm not sure whether OFFSET_TYPE needs this treatment,
2362 	 so I'll play safe and return 1.  */
2363     case OFFSET_TYPE:
2364       return 1;
2365 
2366     case RECORD_TYPE:
2367     case UNION_TYPE:
2368     case QUAL_UNION_TYPE:
2369       {
2370 	tree fields;
2371 	/* For a type that has fields, see if the fields have pointers.  */
2372 	for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2373 	  if (TREE_CODE (fields) == FIELD_DECL
2374 	      && contains_pointers_p (TREE_TYPE (fields)))
2375 	    return 1;
2376 	return 0;
2377       }
2378 
2379     case ARRAY_TYPE:
2380       /* An array type contains pointers if its element type does.  */
2381       return contains_pointers_p (TREE_TYPE (type));
2382 
2383     default:
2384       return 0;
2385     }
2386 }
2387 
2388 /* We delay assemble_external processing until
2389    the compilation unit is finalized.  This is the best we can do for
2390    right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2391    it all the way to final.  See PR 17982 for further discussion.  */
2392 static GTY(()) tree pending_assemble_externals;
2393 
2394 #ifdef ASM_OUTPUT_EXTERNAL
2395 /* Some targets delay some output to final using TARGET_ASM_FILE_END.
2396    As a result, assemble_external can be called after the list of externals
2397    is processed and the pointer set destroyed.  */
2398 static bool pending_assemble_externals_processed;
2399 
2400 /* Avoid O(external_decls**2) lookups in the pending_assemble_externals
2401    TREE_LIST in assemble_external.  */
2402 static hash_set<tree> *pending_assemble_externals_set;
2403 
2404 /* True if DECL is a function decl for which no out-of-line copy exists.
2405    It is assumed that DECL's assembler name has been set.  */
2406 
2407 static bool
incorporeal_function_p(tree decl)2408 incorporeal_function_p (tree decl)
2409 {
2410   if (TREE_CODE (decl) == FUNCTION_DECL && fndecl_built_in_p (decl))
2411     {
2412       const char *name;
2413 
2414       if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2415 	  && ALLOCA_FUNCTION_CODE_P (DECL_FUNCTION_CODE (decl)))
2416 	return true;
2417 
2418       name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2419       /* Atomic or sync builtins which have survived this far will be
2420 	 resolved externally and therefore are not incorporeal.  */
2421       if (strncmp (name, "__builtin_", 10) == 0)
2422 	return true;
2423     }
2424   return false;
2425 }
2426 
2427 /* Actually do the tests to determine if this is necessary, and invoke
2428    ASM_OUTPUT_EXTERNAL.  */
2429 static void
assemble_external_real(tree decl)2430 assemble_external_real (tree decl)
2431 {
2432   rtx rtl = DECL_RTL (decl);
2433 
2434   if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2435       && !SYMBOL_REF_USED (XEXP (rtl, 0))
2436       && !incorporeal_function_p (decl))
2437     {
2438       /* Some systems do require some output.  */
2439       SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2440       ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2441     }
2442 }
2443 #endif
2444 
2445 void
process_pending_assemble_externals(void)2446 process_pending_assemble_externals (void)
2447 {
2448 #ifdef ASM_OUTPUT_EXTERNAL
2449   tree list;
2450   for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2451     assemble_external_real (TREE_VALUE (list));
2452 
2453   pending_assemble_externals = 0;
2454   pending_assemble_externals_processed = true;
2455   delete pending_assemble_externals_set;
2456 #endif
2457 }
2458 
2459 /* This TREE_LIST contains any weak symbol declarations waiting
2460    to be emitted.  */
2461 static GTY(()) tree weak_decls;
2462 
2463 /* Output something to declare an external symbol to the assembler,
2464    and qualifiers such as weakness.  (Most assemblers don't need
2465    extern declaration, so we normally output nothing.)  Do nothing if
2466    DECL is not external.  */
2467 
2468 void
assemble_external(tree decl ATTRIBUTE_UNUSED)2469 assemble_external (tree decl ATTRIBUTE_UNUSED)
2470 {
2471   /*  Make sure that the ASM_OUT_FILE is open.
2472       If it's not, we should not be calling this function.  */
2473   gcc_assert (asm_out_file);
2474 
2475   /* In a perfect world, the following condition would be true.
2476      Sadly, the Go front end emit assembly *from the front end*,
2477      bypassing the call graph.  See PR52739.  Fix before GCC 4.8.  */
2478 #if 0
2479   /* This function should only be called if we are expanding, or have
2480      expanded, to RTL.
2481      Ideally, only final.c would be calling this function, but it is
2482      not clear whether that would break things somehow.  See PR 17982
2483      for further discussion.  */
2484   gcc_assert (state == EXPANSION
2485 	      || state == FINISHED);
2486 #endif
2487 
2488   if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2489     return;
2490 
2491   /* We want to output annotation for weak and external symbols at
2492      very last to check if they are references or not.  */
2493 
2494   if (TARGET_SUPPORTS_WEAK
2495       && DECL_WEAK (decl)
2496       /* TREE_STATIC is a weird and abused creature which is not
2497 	 generally the right test for whether an entity has been
2498 	 locally emitted, inlined or otherwise not-really-extern, but
2499 	 for declarations that can be weak, it happens to be
2500 	 match.  */
2501       && !TREE_STATIC (decl)
2502       && lookup_attribute ("weak", DECL_ATTRIBUTES (decl))
2503       && value_member (decl, weak_decls) == NULL_TREE)
2504     weak_decls = tree_cons (NULL, decl, weak_decls);
2505 
2506 #ifdef ASM_OUTPUT_EXTERNAL
2507   if (pending_assemble_externals_processed)
2508     {
2509       assemble_external_real (decl);
2510       return;
2511     }
2512 
2513   if (! pending_assemble_externals_set->add (decl))
2514     pending_assemble_externals = tree_cons (NULL, decl,
2515 					    pending_assemble_externals);
2516 #endif
2517 }
2518 
2519 /* Similar, for calling a library function FUN.  */
2520 
2521 void
assemble_external_libcall(rtx fun)2522 assemble_external_libcall (rtx fun)
2523 {
2524   /* Declare library function name external when first used, if nec.  */
2525   if (! SYMBOL_REF_USED (fun))
2526     {
2527       SYMBOL_REF_USED (fun) = 1;
2528       targetm.asm_out.external_libcall (fun);
2529     }
2530 }
2531 
2532 /* Assemble a label named NAME.  */
2533 
2534 void
assemble_label(FILE * file,const char * name)2535 assemble_label (FILE *file, const char *name)
2536 {
2537   ASM_OUTPUT_LABEL (file, name);
2538 }
2539 
2540 /* Set the symbol_referenced flag for ID.  */
2541 void
mark_referenced(tree id)2542 mark_referenced (tree id)
2543 {
2544   TREE_SYMBOL_REFERENCED (id) = 1;
2545 }
2546 
2547 /* Set the symbol_referenced flag for DECL and notify callgraph.  */
2548 void
mark_decl_referenced(tree decl)2549 mark_decl_referenced (tree decl)
2550 {
2551   if (TREE_CODE (decl) == FUNCTION_DECL)
2552     {
2553       /* Extern inline functions don't become needed when referenced.
2554 	 If we know a method will be emitted in other TU and no new
2555 	 functions can be marked reachable, just use the external
2556 	 definition.  */
2557       struct cgraph_node *node = cgraph_node::get_create (decl);
2558       if (!DECL_EXTERNAL (decl)
2559 	  && !node->definition)
2560 	node->mark_force_output ();
2561     }
2562   else if (VAR_P (decl))
2563     {
2564       varpool_node *node = varpool_node::get_create (decl);
2565       /* C++ frontend use mark_decl_references to force COMDAT variables
2566          to be output that might appear dead otherwise.  */
2567       node->force_output = true;
2568     }
2569   /* else do nothing - we can get various sorts of CST nodes here,
2570      which do not need to be marked.  */
2571 }
2572 
2573 
2574 /* Output to FILE (an assembly file) a reference to NAME.  If NAME
2575    starts with a *, the rest of NAME is output verbatim.  Otherwise
2576    NAME is transformed in a target-specific way (usually by the
2577    addition of an underscore).  */
2578 
2579 void
assemble_name_raw(FILE * file,const char * name)2580 assemble_name_raw (FILE *file, const char *name)
2581 {
2582   if (name[0] == '*')
2583     fputs (&name[1], file);
2584   else
2585     ASM_OUTPUT_LABELREF (file, name);
2586 }
2587 
2588 /* Return NAME that should actually be emitted, looking through
2589    transparent aliases.  If NAME refers to an entity that is also
2590    represented as a tree (like a function or variable), mark the entity
2591    as referenced.  */
2592 const char *
assemble_name_resolve(const char * name)2593 assemble_name_resolve (const char *name)
2594 {
2595   const char *real_name = targetm.strip_name_encoding (name);
2596   tree id = maybe_get_identifier (real_name);
2597 
2598   if (id)
2599     {
2600       tree id_orig = id;
2601 
2602       mark_referenced (id);
2603       ultimate_transparent_alias_target (&id);
2604       if (id != id_orig)
2605 	name = IDENTIFIER_POINTER (id);
2606       gcc_assert (! TREE_CHAIN (id));
2607     }
2608 
2609   return name;
2610 }
2611 
2612 /* Like assemble_name_raw, but should be used when NAME might refer to
2613    an entity that is also represented as a tree (like a function or
2614    variable).  If NAME does refer to such an entity, that entity will
2615    be marked as referenced.  */
2616 
2617 void
assemble_name(FILE * file,const char * name)2618 assemble_name (FILE *file, const char *name)
2619 {
2620   assemble_name_raw (file, assemble_name_resolve (name));
2621 }
2622 
2623 /* Allocate SIZE bytes writable static space with a gensym name
2624    and return an RTX to refer to its address.  */
2625 
2626 rtx
assemble_static_space(unsigned HOST_WIDE_INT size)2627 assemble_static_space (unsigned HOST_WIDE_INT size)
2628 {
2629   char name[17];
2630   const char *namestring;
2631   rtx x;
2632 
2633   ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2634   ++const_labelno;
2635   namestring = ggc_strdup (name);
2636 
2637   x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2638   SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2639 
2640 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2641   ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2642 				 BIGGEST_ALIGNMENT);
2643 #else
2644 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2645   ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2646 #else
2647   {
2648     /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2649        so that each uninitialized object starts on such a boundary.  */
2650     /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL.  */
2651     unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2652       = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2653 	 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2654 	 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2655     ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2656   }
2657 #endif
2658 #endif
2659   return x;
2660 }
2661 
2662 /* Assemble the static constant template for function entry trampolines.
2663    This is done at most once per compilation.
2664    Returns an RTX for the address of the template.  */
2665 
2666 static GTY(()) rtx initial_trampoline;
2667 
2668 rtx
assemble_trampoline_template(void)2669 assemble_trampoline_template (void)
2670 {
2671   char label[256];
2672   const char *name;
2673   int align;
2674   rtx symbol;
2675 
2676   gcc_assert (targetm.asm_out.trampoline_template != NULL);
2677 
2678   if (initial_trampoline)
2679     return initial_trampoline;
2680 
2681   /* By default, put trampoline templates in read-only data section.  */
2682 
2683 #ifdef TRAMPOLINE_SECTION
2684   switch_to_section (TRAMPOLINE_SECTION);
2685 #else
2686   switch_to_section (readonly_data_section);
2687 #endif
2688 
2689   /* Write the assembler code to define one.  */
2690   align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2691   if (align > 0)
2692     ASM_OUTPUT_ALIGN (asm_out_file, align);
2693 
2694   targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2695   targetm.asm_out.trampoline_template (asm_out_file);
2696 
2697   /* Record the rtl to refer to it.  */
2698   ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2699   name = ggc_strdup (label);
2700   symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2701   SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2702 
2703   initial_trampoline = gen_const_mem (BLKmode, symbol);
2704   set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2705   set_mem_size (initial_trampoline, TRAMPOLINE_SIZE);
2706 
2707   return initial_trampoline;
2708 }
2709 
2710 /* A and B are either alignments or offsets.  Return the minimum alignment
2711    that may be assumed after adding the two together.  */
2712 
2713 static inline unsigned
min_align(unsigned int a,unsigned int b)2714 min_align (unsigned int a, unsigned int b)
2715 {
2716   return least_bit_hwi (a | b);
2717 }
2718 
2719 /* Return the assembler directive for creating a given kind of integer
2720    object.  SIZE is the number of bytes in the object and ALIGNED_P
2721    indicates whether it is known to be aligned.  Return NULL if the
2722    assembly dialect has no such directive.
2723 
2724    The returned string should be printed at the start of a new line and
2725    be followed immediately by the object's initial value.  */
2726 
2727 const char *
integer_asm_op(int size,int aligned_p)2728 integer_asm_op (int size, int aligned_p)
2729 {
2730   struct asm_int_op *ops;
2731 
2732   if (aligned_p)
2733     ops = &targetm.asm_out.aligned_op;
2734   else
2735     ops = &targetm.asm_out.unaligned_op;
2736 
2737   switch (size)
2738     {
2739     case 1:
2740       return targetm.asm_out.byte_op;
2741     case 2:
2742       return ops->hi;
2743     case 3:
2744       return ops->psi;
2745     case 4:
2746       return ops->si;
2747     case 5:
2748     case 6:
2749     case 7:
2750       return ops->pdi;
2751     case 8:
2752       return ops->di;
2753     case 9:
2754     case 10:
2755     case 11:
2756     case 12:
2757     case 13:
2758     case 14:
2759     case 15:
2760       return ops->pti;
2761     case 16:
2762       return ops->ti;
2763     default:
2764       return NULL;
2765     }
2766 }
2767 
2768 /* Use directive OP to assemble an integer object X.  Print OP at the
2769    start of the line, followed immediately by the value of X.  */
2770 
2771 void
assemble_integer_with_op(const char * op,rtx x)2772 assemble_integer_with_op (const char *op, rtx x)
2773 {
2774   fputs (op, asm_out_file);
2775   output_addr_const (asm_out_file, x);
2776   fputc ('\n', asm_out_file);
2777 }
2778 
2779 /* The default implementation of the asm_out.integer target hook.  */
2780 
2781 bool
default_assemble_integer(rtx x ATTRIBUTE_UNUSED,unsigned int size ATTRIBUTE_UNUSED,int aligned_p ATTRIBUTE_UNUSED)2782 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2783 			  unsigned int size ATTRIBUTE_UNUSED,
2784 			  int aligned_p ATTRIBUTE_UNUSED)
2785 {
2786   const char *op = integer_asm_op (size, aligned_p);
2787   /* Avoid GAS bugs for large values.  Specifically negative values whose
2788      absolute value fits in a bfd_vma, but not in a bfd_signed_vma.  */
2789   if (size > UNITS_PER_WORD && size > POINTER_SIZE_UNITS)
2790     return false;
2791   return op && (assemble_integer_with_op (op, x), true);
2792 }
2793 
2794 /* Assemble the integer constant X into an object of SIZE bytes.  ALIGN is
2795    the alignment of the integer in bits.  Return 1 if we were able to output
2796    the constant, otherwise 0.  We must be able to output the constant,
2797    if FORCE is nonzero.  */
2798 
2799 bool
assemble_integer(rtx x,unsigned int size,unsigned int align,int force)2800 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2801 {
2802   int aligned_p;
2803 
2804   aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2805 
2806   /* See if the target hook can handle this kind of object.  */
2807   if (targetm.asm_out.integer (x, size, aligned_p))
2808     return true;
2809 
2810   /* If the object is a multi-byte one, try splitting it up.  Split
2811      it into words it if is multi-word, otherwise split it into bytes.  */
2812   if (size > 1)
2813     {
2814       machine_mode omode, imode;
2815       unsigned int subalign;
2816       unsigned int subsize, i;
2817       enum mode_class mclass;
2818 
2819       subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2820       subalign = MIN (align, subsize * BITS_PER_UNIT);
2821       if (GET_CODE (x) == CONST_FIXED)
2822 	mclass = GET_MODE_CLASS (GET_MODE (x));
2823       else
2824 	mclass = MODE_INT;
2825 
2826       omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0).require ();
2827       imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0).require ();
2828 
2829       for (i = 0; i < size; i += subsize)
2830 	{
2831 	  rtx partial = simplify_subreg (omode, x, imode, i);
2832 	  if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2833 	    break;
2834 	}
2835       if (i == size)
2836 	return true;
2837 
2838       /* If we've printed some of it, but not all of it, there's no going
2839 	 back now.  */
2840       gcc_assert (!i);
2841     }
2842 
2843   gcc_assert (!force);
2844 
2845   return false;
2846 }
2847 
2848 /* Assemble the floating-point constant D into an object of size MODE.  ALIGN
2849    is the alignment of the constant in bits.  If REVERSE is true, D is output
2850    in reverse storage order.  */
2851 
2852 void
assemble_real(REAL_VALUE_TYPE d,scalar_float_mode mode,unsigned int align,bool reverse)2853 assemble_real (REAL_VALUE_TYPE d, scalar_float_mode mode, unsigned int align,
2854 	       bool reverse)
2855 {
2856   long data[4] = {0, 0, 0, 0};
2857   int bitsize, nelts, nunits, units_per;
2858   rtx elt;
2859 
2860   /* This is hairy.  We have a quantity of known size.  real_to_target
2861      will put it into an array of *host* longs, 32 bits per element
2862      (even if long is more than 32 bits).  We need to determine the
2863      number of array elements that are occupied (nelts) and the number
2864      of *target* min-addressable units that will be occupied in the
2865      object file (nunits).  We cannot assume that 32 divides the
2866      mode's bitsize (size * BITS_PER_UNIT) evenly.
2867 
2868      size * BITS_PER_UNIT is used here to make sure that padding bits
2869      (which might appear at either end of the value; real_to_target
2870      will include the padding bits in its output array) are included.  */
2871 
2872   nunits = GET_MODE_SIZE (mode);
2873   bitsize = nunits * BITS_PER_UNIT;
2874   nelts = CEIL (bitsize, 32);
2875   units_per = 32 / BITS_PER_UNIT;
2876 
2877   real_to_target (data, &d, mode);
2878 
2879   /* Put out the first word with the specified alignment.  */
2880   if (reverse)
2881     elt = flip_storage_order (SImode, gen_int_mode (data[nelts - 1], SImode));
2882   else
2883     elt = GEN_INT (data[0]);
2884   assemble_integer (elt, MIN (nunits, units_per), align, 1);
2885   nunits -= units_per;
2886 
2887   /* Subsequent words need only 32-bit alignment.  */
2888   align = min_align (align, 32);
2889 
2890   for (int i = 1; i < nelts; i++)
2891     {
2892       if (reverse)
2893 	elt = flip_storage_order (SImode,
2894 				  gen_int_mode (data[nelts - 1 - i], SImode));
2895       else
2896 	elt = GEN_INT (data[i]);
2897       assemble_integer (elt, MIN (nunits, units_per), align, 1);
2898       nunits -= units_per;
2899     }
2900 }
2901 
2902 /* Given an expression EXP with a constant value,
2903    reduce it to the sum of an assembler symbol and an integer.
2904    Store them both in the structure *VALUE.
2905    EXP must be reducible.  */
2906 
2907 struct addr_const {
2908   rtx base;
2909   poly_int64 offset;
2910 };
2911 
2912 static void
decode_addr_const(tree exp,struct addr_const * value)2913 decode_addr_const (tree exp, struct addr_const *value)
2914 {
2915   tree target = TREE_OPERAND (exp, 0);
2916   poly_int64 offset = 0;
2917   rtx x;
2918 
2919   while (1)
2920     {
2921       poly_int64 bytepos;
2922       if (TREE_CODE (target) == COMPONENT_REF
2923 	  && poly_int_tree_p (byte_position (TREE_OPERAND (target, 1)),
2924 			      &bytepos))
2925 	{
2926 	  offset += bytepos;
2927 	  target = TREE_OPERAND (target, 0);
2928 	}
2929       else if (TREE_CODE (target) == ARRAY_REF
2930 	       || TREE_CODE (target) == ARRAY_RANGE_REF)
2931 	{
2932 	  /* Truncate big offset.  */
2933 	  offset
2934 	    += (TREE_INT_CST_LOW (TYPE_SIZE_UNIT (TREE_TYPE (target)))
2935 		* wi::to_poly_widest (TREE_OPERAND (target, 1)).force_shwi ());
2936 	  target = TREE_OPERAND (target, 0);
2937 	}
2938       else if (TREE_CODE (target) == MEM_REF
2939 	       && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR)
2940 	{
2941 	  offset += mem_ref_offset (target).force_shwi ();
2942 	  target = TREE_OPERAND (TREE_OPERAND (target, 0), 0);
2943 	}
2944       else if (TREE_CODE (target) == INDIRECT_REF
2945 	       && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR
2946 	       && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0))
2947 		  == ADDR_EXPR)
2948 	target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0);
2949       else
2950 	break;
2951     }
2952 
2953   switch (TREE_CODE (target))
2954     {
2955     case VAR_DECL:
2956     case FUNCTION_DECL:
2957       x = DECL_RTL (target);
2958       break;
2959 
2960     case LABEL_DECL:
2961       x = gen_rtx_MEM (FUNCTION_MODE,
2962 		       gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2963       break;
2964 
2965     case REAL_CST:
2966     case FIXED_CST:
2967     case STRING_CST:
2968     case COMPLEX_CST:
2969     case CONSTRUCTOR:
2970     case INTEGER_CST:
2971       x = lookup_constant_def (target);
2972       /* Should have been added by output_addressed_constants.  */
2973       gcc_assert (x);
2974       break;
2975 
2976     case INDIRECT_REF:
2977       /* This deals with absolute addresses.  */
2978       offset += tree_to_shwi (TREE_OPERAND (target, 0));
2979       x = gen_rtx_MEM (QImode,
2980 		       gen_rtx_SYMBOL_REF (Pmode, "origin of addresses"));
2981       break;
2982 
2983     case COMPOUND_LITERAL_EXPR:
2984       gcc_assert (COMPOUND_LITERAL_EXPR_DECL (target));
2985       x = DECL_RTL (COMPOUND_LITERAL_EXPR_DECL (target));
2986       break;
2987 
2988     default:
2989       gcc_unreachable ();
2990     }
2991 
2992   gcc_assert (MEM_P (x));
2993   x = XEXP (x, 0);
2994 
2995   value->base = x;
2996   value->offset = offset;
2997 }
2998 
2999 static GTY(()) hash_table<tree_descriptor_hasher> *const_desc_htab;
3000 
3001 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
3002 
3003 /* Constant pool accessor function.  */
3004 
3005 hash_table<tree_descriptor_hasher> *
constant_pool_htab(void)3006 constant_pool_htab (void)
3007 {
3008   return const_desc_htab;
3009 }
3010 
3011 /* Compute a hash code for a constant expression.  */
3012 
3013 hashval_t
hash(constant_descriptor_tree * ptr)3014 tree_descriptor_hasher::hash (constant_descriptor_tree *ptr)
3015 {
3016   return ptr->hash;
3017 }
3018 
3019 static hashval_t
const_hash_1(const tree exp)3020 const_hash_1 (const tree exp)
3021 {
3022   const char *p;
3023   hashval_t hi;
3024   int len, i;
3025   enum tree_code code = TREE_CODE (exp);
3026 
3027   /* Either set P and LEN to the address and len of something to hash and
3028      exit the switch or return a value.  */
3029 
3030   switch (code)
3031     {
3032     case INTEGER_CST:
3033       p = (char *) &TREE_INT_CST_ELT (exp, 0);
3034       len = TREE_INT_CST_NUNITS (exp) * sizeof (HOST_WIDE_INT);
3035       break;
3036 
3037     case REAL_CST:
3038       return real_hash (TREE_REAL_CST_PTR (exp));
3039 
3040     case FIXED_CST:
3041       return fixed_hash (TREE_FIXED_CST_PTR (exp));
3042 
3043     case STRING_CST:
3044       p = TREE_STRING_POINTER (exp);
3045       len = TREE_STRING_LENGTH (exp);
3046       break;
3047 
3048     case COMPLEX_CST:
3049       return (const_hash_1 (TREE_REALPART (exp)) * 5
3050 	      + const_hash_1 (TREE_IMAGPART (exp)));
3051 
3052     case VECTOR_CST:
3053       {
3054 	hi = 7 + VECTOR_CST_NPATTERNS (exp);
3055 	hi = hi * 563 + VECTOR_CST_NELTS_PER_PATTERN (exp);
3056 	unsigned int count = vector_cst_encoded_nelts (exp);
3057 	for (unsigned int i = 0; i < count; ++i)
3058 	  hi = hi * 563 + const_hash_1 (VECTOR_CST_ENCODED_ELT (exp, i));
3059 	return hi;
3060       }
3061 
3062     case CONSTRUCTOR:
3063       {
3064 	unsigned HOST_WIDE_INT idx;
3065 	tree value;
3066 
3067 	hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
3068 
3069 	FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
3070 	  if (value)
3071 	    hi = hi * 603 + const_hash_1 (value);
3072 
3073 	return hi;
3074       }
3075 
3076     case ADDR_EXPR:
3077       if (CONSTANT_CLASS_P (TREE_OPERAND (exp, 0)))
3078        return const_hash_1 (TREE_OPERAND (exp, 0));
3079 
3080       /* Fallthru.  */
3081     case FDESC_EXPR:
3082       {
3083 	struct addr_const value;
3084 
3085 	decode_addr_const (exp, &value);
3086 	switch (GET_CODE (value.base))
3087 	  {
3088 	  case SYMBOL_REF:
3089 	    /* Don't hash the address of the SYMBOL_REF;
3090 	       only use the offset and the symbol name.  */
3091 	    hi = value.offset.coeffs[0];
3092 	    p = XSTR (value.base, 0);
3093 	    for (i = 0; p[i] != 0; i++)
3094 	      hi = ((hi * 613) + (unsigned) (p[i]));
3095 	    break;
3096 
3097 	  case LABEL_REF:
3098 	    hi = (value.offset.coeffs[0]
3099 		  + CODE_LABEL_NUMBER (label_ref_label (value.base)) * 13);
3100 	    break;
3101 
3102 	  default:
3103 	    gcc_unreachable ();
3104 	  }
3105       }
3106       return hi;
3107 
3108     case PLUS_EXPR:
3109     case POINTER_PLUS_EXPR:
3110     case MINUS_EXPR:
3111       return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
3112 	      + const_hash_1 (TREE_OPERAND (exp, 1)));
3113 
3114     CASE_CONVERT:
3115       return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
3116 
3117     default:
3118       /* A language specific constant. Just hash the code.  */
3119       return code;
3120     }
3121 
3122   /* Compute hashing function.  */
3123   hi = len;
3124   for (i = 0; i < len; i++)
3125     hi = ((hi * 613) + (unsigned) (p[i]));
3126 
3127   return hi;
3128 }
3129 
3130 /* Wrapper of compare_constant, for the htab interface.  */
3131 bool
equal(constant_descriptor_tree * c1,constant_descriptor_tree * c2)3132 tree_descriptor_hasher::equal (constant_descriptor_tree *c1,
3133 			       constant_descriptor_tree *c2)
3134 {
3135   if (c1->hash != c2->hash)
3136     return 0;
3137   return compare_constant (c1->value, c2->value);
3138 }
3139 
3140 /* Compare t1 and t2, and return 1 only if they are known to result in
3141    the same bit pattern on output.  */
3142 
3143 static int
compare_constant(const tree t1,const tree t2)3144 compare_constant (const tree t1, const tree t2)
3145 {
3146   enum tree_code typecode;
3147 
3148   if (t1 == NULL_TREE)
3149     return t2 == NULL_TREE;
3150   if (t2 == NULL_TREE)
3151     return 0;
3152 
3153   if (TREE_CODE (t1) != TREE_CODE (t2))
3154     return 0;
3155 
3156   switch (TREE_CODE (t1))
3157     {
3158     case INTEGER_CST:
3159       /* Integer constants are the same only if the same width of type.  */
3160       if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3161 	return 0;
3162       if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3163 	return 0;
3164       return tree_int_cst_equal (t1, t2);
3165 
3166     case REAL_CST:
3167       /* Real constants are the same only if the same width of type.  In
3168 	 addition to the same width, we need to check whether the modes are the
3169 	 same.  There might be two floating point modes that are the same size
3170 	 but have different representations, such as the PowerPC that has 2
3171 	 different 128-bit floating point types (IBM extended double and IEEE
3172 	 128-bit floating point).  */
3173       if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3174 	return 0;
3175       if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3176 	return 0;
3177       return real_identical (&TREE_REAL_CST (t1), &TREE_REAL_CST (t2));
3178 
3179     case FIXED_CST:
3180       /* Fixed constants are the same only if the same width of type.  */
3181       if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3182 	return 0;
3183 
3184       return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
3185 
3186     case STRING_CST:
3187       if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
3188 	  || int_size_in_bytes (TREE_TYPE (t1))
3189 	     != int_size_in_bytes (TREE_TYPE (t2)))
3190 	return 0;
3191 
3192       return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
3193 	      && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
3194 			 TREE_STRING_LENGTH (t1)));
3195 
3196     case COMPLEX_CST:
3197       return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
3198 	      && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
3199 
3200     case VECTOR_CST:
3201       {
3202 	if (VECTOR_CST_NPATTERNS (t1)
3203 	    != VECTOR_CST_NPATTERNS (t2))
3204 	  return 0;
3205 
3206 	if (VECTOR_CST_NELTS_PER_PATTERN (t1)
3207 	    != VECTOR_CST_NELTS_PER_PATTERN (t2))
3208 	  return 0;
3209 
3210 	unsigned int count = vector_cst_encoded_nelts (t1);
3211 	for (unsigned int i = 0; i < count; ++i)
3212 	  if (!compare_constant (VECTOR_CST_ENCODED_ELT (t1, i),
3213 				 VECTOR_CST_ENCODED_ELT (t2, i)))
3214 	    return 0;
3215 
3216 	return 1;
3217       }
3218 
3219     case CONSTRUCTOR:
3220       {
3221 	vec<constructor_elt, va_gc> *v1, *v2;
3222 	unsigned HOST_WIDE_INT idx;
3223 
3224 	typecode = TREE_CODE (TREE_TYPE (t1));
3225 	if (typecode != TREE_CODE (TREE_TYPE (t2)))
3226 	  return 0;
3227 
3228 	if (typecode == ARRAY_TYPE)
3229 	  {
3230 	    HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
3231 	    /* For arrays, check that mode, size and storage order match.  */
3232 	    if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
3233 		|| size_1 == -1
3234 		|| size_1 != int_size_in_bytes (TREE_TYPE (t2))
3235 		|| TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (t1))
3236 		   != TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (t2)))
3237 	      return 0;
3238 	  }
3239 	else
3240 	  {
3241 	    /* For record and union constructors, require exact type
3242                equality.  */
3243 	    if (TREE_TYPE (t1) != TREE_TYPE (t2))
3244 	      return 0;
3245 	  }
3246 
3247 	v1 = CONSTRUCTOR_ELTS (t1);
3248 	v2 = CONSTRUCTOR_ELTS (t2);
3249 	if (vec_safe_length (v1) != vec_safe_length (v2))
3250 	  return 0;
3251 
3252 	for (idx = 0; idx < vec_safe_length (v1); ++idx)
3253 	  {
3254 	    constructor_elt *c1 = &(*v1)[idx];
3255 	    constructor_elt *c2 = &(*v2)[idx];
3256 
3257 	    /* Check that each value is the same...  */
3258 	    if (!compare_constant (c1->value, c2->value))
3259 	      return 0;
3260 	    /* ... and that they apply to the same fields!  */
3261 	    if (typecode == ARRAY_TYPE)
3262 	      {
3263 		if (!compare_constant (c1->index, c2->index))
3264 		  return 0;
3265 	      }
3266 	    else
3267 	      {
3268 		if (c1->index != c2->index)
3269 		  return 0;
3270 	      }
3271 	  }
3272 
3273 	return 1;
3274       }
3275 
3276     case ADDR_EXPR:
3277     case FDESC_EXPR:
3278       {
3279 	struct addr_const value1, value2;
3280 	enum rtx_code code;
3281 	int ret;
3282 
3283 	decode_addr_const (t1, &value1);
3284 	decode_addr_const (t2, &value2);
3285 
3286 	if (maybe_ne (value1.offset, value2.offset))
3287 	  return 0;
3288 
3289 	code = GET_CODE (value1.base);
3290 	if (code != GET_CODE (value2.base))
3291 	  return 0;
3292 
3293 	switch (code)
3294 	  {
3295 	  case SYMBOL_REF:
3296 	    ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3297 	    break;
3298 
3299 	  case LABEL_REF:
3300 	    ret = (CODE_LABEL_NUMBER (label_ref_label (value1.base))
3301 		   == CODE_LABEL_NUMBER (label_ref_label (value2.base)));
3302 	    break;
3303 
3304 	  default:
3305 	    gcc_unreachable ();
3306 	  }
3307 	return ret;
3308       }
3309 
3310     case PLUS_EXPR:
3311     case POINTER_PLUS_EXPR:
3312     case MINUS_EXPR:
3313     case RANGE_EXPR:
3314       return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3315 	      && compare_constant (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3316 
3317     CASE_CONVERT:
3318     case VIEW_CONVERT_EXPR:
3319       return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3320 
3321     default:
3322       return 0;
3323     }
3324 
3325   gcc_unreachable ();
3326 }
3327 
3328 /* Return the section into which constant EXP should be placed.  */
3329 
3330 static section *
get_constant_section(tree exp,unsigned int align)3331 get_constant_section (tree exp, unsigned int align)
3332 {
3333   return targetm.asm_out.select_section (exp,
3334 					 compute_reloc_for_constant (exp),
3335 					 align);
3336 }
3337 
3338 /* Return the size of constant EXP in bytes.  */
3339 
3340 static HOST_WIDE_INT
get_constant_size(tree exp)3341 get_constant_size (tree exp)
3342 {
3343   HOST_WIDE_INT size;
3344 
3345   size = int_size_in_bytes (TREE_TYPE (exp));
3346   gcc_checking_assert (size >= 0);
3347   gcc_checking_assert (TREE_CODE (exp) != STRING_CST
3348 		       || size >= TREE_STRING_LENGTH (exp));
3349   return size;
3350 }
3351 
3352 /* Subroutine of output_constant_def:
3353    No constant equal to EXP is known to have been output.
3354    Make a constant descriptor to enter EXP in the hash table.
3355    Assign the label number and construct RTL to refer to the
3356    constant's location in memory.
3357    Caller is responsible for updating the hash table.  */
3358 
3359 static struct constant_descriptor_tree *
build_constant_desc(tree exp)3360 build_constant_desc (tree exp)
3361 {
3362   struct constant_descriptor_tree *desc;
3363   rtx symbol, rtl;
3364   char label[256];
3365   int labelno;
3366   tree decl;
3367 
3368   desc = ggc_alloc<constant_descriptor_tree> ();
3369   desc->value = exp;
3370 
3371   /* Create a string containing the label name, in LABEL.  */
3372   labelno = const_labelno++;
3373   ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3374 
3375   /* Construct the VAR_DECL associated with the constant.  */
3376   decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3377 		     TREE_TYPE (exp));
3378   DECL_ARTIFICIAL (decl) = 1;
3379   DECL_IGNORED_P (decl) = 1;
3380   TREE_READONLY (decl) = 1;
3381   TREE_STATIC (decl) = 1;
3382   TREE_ADDRESSABLE (decl) = 1;
3383   /* We don't set the RTL yet as this would cause varpool to assume that the
3384      variable is referenced.  Moreover, it would just be dropped in LTO mode.
3385      Instead we set the flag that will be recognized in make_decl_rtl.  */
3386   DECL_IN_CONSTANT_POOL (decl) = 1;
3387   DECL_INITIAL (decl) = desc->value;
3388   /* ??? targetm.constant_alignment hasn't been updated for vector types on
3389      most architectures so use DATA_ALIGNMENT as well, except for strings.  */
3390   if (TREE_CODE (exp) == STRING_CST)
3391     SET_DECL_ALIGN (decl, targetm.constant_alignment (exp, DECL_ALIGN (decl)));
3392   else
3393     align_variable (decl, 0);
3394 
3395   /* Now construct the SYMBOL_REF and the MEM.  */
3396   if (use_object_blocks_p ())
3397     {
3398       int align = (TREE_CODE (decl) == CONST_DECL
3399 		   || (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
3400 		   ? DECL_ALIGN (decl)
3401 		   : symtab_node::get (decl)->definition_alignment ());
3402       section *sect = get_constant_section (exp, align);
3403       symbol = create_block_symbol (ggc_strdup (label),
3404 				    get_block_for_section (sect), -1);
3405     }
3406   else
3407     symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3408   SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3409   SET_SYMBOL_REF_DECL (symbol, decl);
3410   TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3411 
3412   rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3413   set_mem_attributes (rtl, exp, 1);
3414   set_mem_alias_set (rtl, 0);
3415 
3416   /* Putting EXP into the literal pool might have imposed a different
3417      alignment which should be visible in the RTX as well.  */
3418   set_mem_align (rtl, DECL_ALIGN (decl));
3419 
3420   /* We cannot share RTX'es in pool entries.
3421      Mark this piece of RTL as required for unsharing.  */
3422   RTX_FLAG (rtl, used) = 1;
3423 
3424   /* Set flags or add text to the name to record information, such as
3425      that it is a local symbol.  If the name is changed, the macro
3426      ASM_OUTPUT_LABELREF will have to know how to strip this
3427      information.  This call might invalidate our local variable
3428      SYMBOL; we can't use it afterward.  */
3429   targetm.encode_section_info (exp, rtl, true);
3430 
3431   desc->rtl = rtl;
3432 
3433   return desc;
3434 }
3435 
3436 /* Subroutine of output_constant_def and tree_output_constant_def:
3437    Add a constant to the hash table that tracks which constants
3438    already have labels.  */
3439 
3440 static constant_descriptor_tree *
add_constant_to_table(tree exp)3441 add_constant_to_table (tree exp)
3442 {
3443   /* The hash table methods may call output_constant_def for addressed
3444      constants, so handle them first.  */
3445   output_addressed_constants (exp);
3446 
3447   /* Sanity check to catch recursive insertion.  */
3448   static bool inserting;
3449   gcc_assert (!inserting);
3450   inserting = true;
3451 
3452   /* Look up EXP in the table of constant descriptors.  If we didn't
3453      find it, create a new one.  */
3454   struct constant_descriptor_tree key;
3455   key.value = exp;
3456   key.hash = const_hash_1 (exp);
3457   constant_descriptor_tree **loc
3458     = const_desc_htab->find_slot_with_hash (&key, key.hash, INSERT);
3459 
3460   inserting = false;
3461 
3462   struct constant_descriptor_tree *desc = *loc;
3463   if (!desc)
3464     {
3465       desc = build_constant_desc (exp);
3466       desc->hash = key.hash;
3467       *loc = desc;
3468     }
3469 
3470   return desc;
3471 }
3472 
3473 /* Return an rtx representing a reference to constant data in memory
3474    for the constant expression EXP.
3475 
3476    If assembler code for such a constant has already been output,
3477    return an rtx to refer to it.
3478    Otherwise, output such a constant in memory
3479    and generate an rtx for it.
3480 
3481    If DEFER is nonzero, this constant can be deferred and output only
3482    if referenced in the function after all optimizations.
3483 
3484    `const_desc_table' records which constants already have label strings.  */
3485 
3486 rtx
output_constant_def(tree exp,int defer)3487 output_constant_def (tree exp, int defer)
3488 {
3489   struct constant_descriptor_tree *desc = add_constant_to_table (exp);
3490   maybe_output_constant_def_contents (desc, defer);
3491   return desc->rtl;
3492 }
3493 
3494 /* Subroutine of output_constant_def: Decide whether or not we need to
3495    output the constant DESC now, and if so, do it.  */
3496 static void
maybe_output_constant_def_contents(struct constant_descriptor_tree * desc,int defer)3497 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3498 				    int defer)
3499 {
3500   rtx symbol = XEXP (desc->rtl, 0);
3501   tree exp = desc->value;
3502 
3503   if (flag_syntax_only)
3504     return;
3505 
3506   if (TREE_ASM_WRITTEN (exp))
3507     /* Already output; don't do it again.  */
3508     return;
3509 
3510   /* We can always defer constants as long as the context allows
3511      doing so.  */
3512   if (defer)
3513     {
3514       /* Increment n_deferred_constants if it exists.  It needs to be at
3515 	 least as large as the number of constants actually referred to
3516 	 by the function.  If it's too small we'll stop looking too early
3517 	 and fail to emit constants; if it's too large we'll only look
3518 	 through the entire function when we could have stopped earlier.  */
3519       if (cfun)
3520 	n_deferred_constants++;
3521       return;
3522     }
3523 
3524   output_constant_def_contents (symbol);
3525 }
3526 
3527 /* Subroutine of output_constant_def_contents.  Output the definition
3528    of constant EXP, which is pointed to by label LABEL.  ALIGN is the
3529    constant's alignment in bits.  */
3530 
3531 static void
assemble_constant_contents(tree exp,const char * label,unsigned int align,bool merge_strings)3532 assemble_constant_contents (tree exp, const char *label, unsigned int align,
3533 			    bool merge_strings)
3534 {
3535   HOST_WIDE_INT size;
3536 
3537   size = get_constant_size (exp);
3538 
3539   /* Do any machine/system dependent processing of the constant.  */
3540   targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3541 
3542   /* Output the value of EXP.  */
3543   output_constant (exp, size, align, false, merge_strings);
3544 
3545   targetm.asm_out.decl_end ();
3546 }
3547 
3548 /* We must output the constant data referred to by SYMBOL; do so.  */
3549 
3550 static void
output_constant_def_contents(rtx symbol)3551 output_constant_def_contents (rtx symbol)
3552 {
3553   tree decl = SYMBOL_REF_DECL (symbol);
3554   tree exp = DECL_INITIAL (decl);
3555   bool asan_protected = false;
3556 
3557   /* Make sure any other constants whose addresses appear in EXP
3558      are assigned label numbers.  */
3559   output_addressed_constants (exp);
3560 
3561   /* We are no longer deferring this constant.  */
3562   TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3563 
3564   if ((flag_sanitize & SANITIZE_ADDRESS)
3565       && TREE_CODE (exp) == STRING_CST
3566       && asan_protect_global (exp))
3567     {
3568       asan_protected = true;
3569       SET_DECL_ALIGN (decl, MAX (DECL_ALIGN (decl),
3570 				 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT));
3571     }
3572 
3573   /* If the constant is part of an object block, make sure that the
3574      decl has been positioned within its block, but do not write out
3575      its definition yet.  output_object_blocks will do that later.  */
3576   if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3577     place_block_symbol (symbol);
3578   else
3579     {
3580       int align = (TREE_CODE (decl) == CONST_DECL
3581 		   || (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
3582 		   ? DECL_ALIGN (decl)
3583 		   : symtab_node::get (decl)->definition_alignment ());
3584       section *sect = get_constant_section (exp, align);
3585       switch_to_section (sect);
3586       if (align > BITS_PER_UNIT)
3587 	ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3588       assemble_constant_contents (exp, XSTR (symbol, 0), align,
3589 				  (sect->common.flags & SECTION_MERGE)
3590 				  && (sect->common.flags & SECTION_STRINGS));
3591       if (asan_protected)
3592 	{
3593 	  HOST_WIDE_INT size = get_constant_size (exp);
3594 	  assemble_zeros (asan_red_zone_size (size));
3595 	}
3596     }
3597 }
3598 
3599 /* Look up EXP in the table of constant descriptors.  Return the rtl
3600    if it has been emitted, else null.  */
3601 
3602 rtx
lookup_constant_def(tree exp)3603 lookup_constant_def (tree exp)
3604 {
3605   struct constant_descriptor_tree key;
3606 
3607   key.value = exp;
3608   key.hash = const_hash_1 (exp);
3609   constant_descriptor_tree *desc
3610     = const_desc_htab->find_with_hash (&key, key.hash);
3611 
3612   return (desc ? desc->rtl : NULL_RTX);
3613 }
3614 
3615 /* Return a tree representing a reference to constant data in memory
3616    for the constant expression EXP.
3617 
3618    This is the counterpart of output_constant_def at the Tree level.  */
3619 
3620 tree
tree_output_constant_def(tree exp)3621 tree_output_constant_def (tree exp)
3622 {
3623   struct constant_descriptor_tree *desc = add_constant_to_table (exp);
3624   tree decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3625   varpool_node::finalize_decl (decl);
3626   return decl;
3627 }
3628 
3629 struct GTY((chain_next ("%h.next"), for_user)) constant_descriptor_rtx {
3630   struct constant_descriptor_rtx *next;
3631   rtx mem;
3632   rtx sym;
3633   rtx constant;
3634   HOST_WIDE_INT offset;
3635   hashval_t hash;
3636   fixed_size_mode mode;
3637   unsigned int align;
3638   int labelno;
3639   int mark;
3640 };
3641 
3642 struct const_rtx_desc_hasher : ggc_ptr_hash<constant_descriptor_rtx>
3643 {
3644   static hashval_t hash (constant_descriptor_rtx *);
3645   static bool equal (constant_descriptor_rtx *, constant_descriptor_rtx *);
3646 };
3647 
3648 /* Used in the hash tables to avoid outputting the same constant
3649    twice.  Unlike 'struct constant_descriptor_tree', RTX constants
3650    are output once per function, not once per file.  */
3651 /* ??? Only a few targets need per-function constant pools.  Most
3652    can use one per-file pool.  Should add a targetm bit to tell the
3653    difference.  */
3654 
3655 struct GTY(()) rtx_constant_pool {
3656   /* Pointers to first and last constant in pool, as ordered by offset.  */
3657   struct constant_descriptor_rtx *first;
3658   struct constant_descriptor_rtx *last;
3659 
3660   /* Hash facility for making memory-constants from constant rtl-expressions.
3661      It is used on RISC machines where immediate integer arguments and
3662      constant addresses are restricted so that such constants must be stored
3663      in memory.  */
3664   hash_table<const_rtx_desc_hasher> *const_rtx_htab;
3665 
3666   /* Current offset in constant pool (does not include any
3667      machine-specific header).  */
3668   HOST_WIDE_INT offset;
3669 };
3670 
3671 /* Hash and compare functions for const_rtx_htab.  */
3672 
3673 hashval_t
hash(constant_descriptor_rtx * desc)3674 const_rtx_desc_hasher::hash (constant_descriptor_rtx *desc)
3675 {
3676   return desc->hash;
3677 }
3678 
3679 bool
equal(constant_descriptor_rtx * x,constant_descriptor_rtx * y)3680 const_rtx_desc_hasher::equal (constant_descriptor_rtx *x,
3681 			      constant_descriptor_rtx *y)
3682 {
3683   if (x->mode != y->mode)
3684     return 0;
3685   return rtx_equal_p (x->constant, y->constant);
3686 }
3687 
3688 /* Hash one component of a constant.  */
3689 
3690 static hashval_t
const_rtx_hash_1(const_rtx x)3691 const_rtx_hash_1 (const_rtx x)
3692 {
3693   unsigned HOST_WIDE_INT hwi;
3694   machine_mode mode;
3695   enum rtx_code code;
3696   hashval_t h;
3697   int i;
3698 
3699   code = GET_CODE (x);
3700   mode = GET_MODE (x);
3701   h = (hashval_t) code * 1048573 + mode;
3702 
3703   switch (code)
3704     {
3705     case CONST_INT:
3706       hwi = INTVAL (x);
3707 
3708     fold_hwi:
3709       {
3710 	int shift = sizeof (hashval_t) * CHAR_BIT;
3711 	const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3712 
3713 	h ^= (hashval_t) hwi;
3714 	for (i = 1; i < n; ++i)
3715 	  {
3716 	    hwi >>= shift;
3717 	    h ^= (hashval_t) hwi;
3718 	  }
3719       }
3720       break;
3721 
3722     case CONST_WIDE_INT:
3723       hwi = 0;
3724       {
3725 	for (i = 0; i < CONST_WIDE_INT_NUNITS (x); i++)
3726 	  hwi ^= CONST_WIDE_INT_ELT (x, i);
3727 	goto fold_hwi;
3728       }
3729 
3730     case CONST_DOUBLE:
3731       if (TARGET_SUPPORTS_WIDE_INT == 0 && mode == VOIDmode)
3732 	{
3733 	  hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3734 	  goto fold_hwi;
3735 	}
3736       else
3737 	h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3738       break;
3739 
3740     case CONST_FIXED:
3741       h ^= fixed_hash (CONST_FIXED_VALUE (x));
3742       break;
3743 
3744     case SYMBOL_REF:
3745       h ^= htab_hash_string (XSTR (x, 0));
3746       break;
3747 
3748     case LABEL_REF:
3749       h = h * 251 + CODE_LABEL_NUMBER (label_ref_label (x));
3750       break;
3751 
3752     case UNSPEC:
3753     case UNSPEC_VOLATILE:
3754       h = h * 251 + XINT (x, 1);
3755       break;
3756 
3757     default:
3758       break;
3759     }
3760 
3761   return h;
3762 }
3763 
3764 /* Compute a hash value for X, which should be a constant.  */
3765 
3766 static hashval_t
const_rtx_hash(rtx x)3767 const_rtx_hash (rtx x)
3768 {
3769   hashval_t h = 0;
3770   subrtx_iterator::array_type array;
3771   FOR_EACH_SUBRTX (iter, array, x, ALL)
3772     h = h * 509 + const_rtx_hash_1 (*iter);
3773   return h;
3774 }
3775 
3776 
3777 /* Create and return a new rtx constant pool.  */
3778 
3779 static struct rtx_constant_pool *
create_constant_pool(void)3780 create_constant_pool (void)
3781 {
3782   struct rtx_constant_pool *pool;
3783 
3784   pool = ggc_alloc<rtx_constant_pool> ();
3785   pool->const_rtx_htab = hash_table<const_rtx_desc_hasher>::create_ggc (31);
3786   pool->first = NULL;
3787   pool->last = NULL;
3788   pool->offset = 0;
3789   return pool;
3790 }
3791 
3792 /* Initialize constant pool hashing for a new function.  */
3793 
3794 void
init_varasm_status(void)3795 init_varasm_status (void)
3796 {
3797   crtl->varasm.pool = create_constant_pool ();
3798   crtl->varasm.deferred_constants = 0;
3799 }
3800 
3801 /* Given a MINUS expression, simplify it if both sides
3802    include the same symbol.  */
3803 
3804 rtx
simplify_subtraction(rtx x)3805 simplify_subtraction (rtx x)
3806 {
3807   rtx r = simplify_rtx (x);
3808   return r ? r : x;
3809 }
3810 
3811 /* Given a constant rtx X, make (or find) a memory constant for its value
3812    and return a MEM rtx to refer to it in memory.  IN_MODE is the mode
3813    of X.  */
3814 
3815 rtx
force_const_mem(machine_mode in_mode,rtx x)3816 force_const_mem (machine_mode in_mode, rtx x)
3817 {
3818   struct constant_descriptor_rtx *desc, tmp;
3819   struct rtx_constant_pool *pool;
3820   char label[256];
3821   rtx def, symbol;
3822   hashval_t hash;
3823   unsigned int align;
3824   constant_descriptor_rtx **slot;
3825   fixed_size_mode mode;
3826 
3827   /* We can't force variable-sized objects to memory.  */
3828   if (!is_a <fixed_size_mode> (in_mode, &mode))
3829     return NULL_RTX;
3830 
3831   /* If we're not allowed to drop X into the constant pool, don't.  */
3832   if (targetm.cannot_force_const_mem (mode, x))
3833     return NULL_RTX;
3834 
3835   /* Record that this function has used a constant pool entry.  */
3836   crtl->uses_const_pool = 1;
3837 
3838   /* Decide which pool to use.  */
3839   pool = (targetm.use_blocks_for_constant_p (mode, x)
3840 	  ? shared_constant_pool
3841 	  : crtl->varasm.pool);
3842 
3843   /* Lookup the value in the hashtable.  */
3844   tmp.constant = x;
3845   tmp.mode = mode;
3846   hash = const_rtx_hash (x);
3847   slot = pool->const_rtx_htab->find_slot_with_hash (&tmp, hash, INSERT);
3848   desc = *slot;
3849 
3850   /* If the constant was already present, return its memory.  */
3851   if (desc)
3852     return copy_rtx (desc->mem);
3853 
3854   /* Otherwise, create a new descriptor.  */
3855   desc = ggc_alloc<constant_descriptor_rtx> ();
3856   *slot = desc;
3857 
3858   /* Align the location counter as required by EXP's data type.  */
3859   machine_mode align_mode = (mode == VOIDmode ? word_mode : mode);
3860   align = targetm.static_rtx_alignment (align_mode);
3861 
3862   pool->offset += (align / BITS_PER_UNIT) - 1;
3863   pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3864 
3865   desc->next = NULL;
3866   desc->constant = copy_rtx (tmp.constant);
3867   desc->offset = pool->offset;
3868   desc->hash = hash;
3869   desc->mode = mode;
3870   desc->align = align;
3871   desc->labelno = const_labelno;
3872   desc->mark = 0;
3873 
3874   pool->offset += GET_MODE_SIZE (mode);
3875   if (pool->last)
3876     pool->last->next = desc;
3877   else
3878     pool->first = pool->last = desc;
3879   pool->last = desc;
3880 
3881   /* Create a string containing the label name, in LABEL.  */
3882   ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3883   ++const_labelno;
3884 
3885   /* Construct the SYMBOL_REF.  Make sure to mark it as belonging to
3886      the constants pool.  */
3887   if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3888     {
3889       section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3890       symbol = create_block_symbol (ggc_strdup (label),
3891 				    get_block_for_section (sect), -1);
3892     }
3893   else
3894     symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3895   desc->sym = symbol;
3896   SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3897   CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3898   SET_SYMBOL_REF_CONSTANT (symbol, desc);
3899 
3900   /* Construct the MEM.  */
3901   desc->mem = def = gen_const_mem (mode, symbol);
3902   set_mem_align (def, align);
3903 
3904   /* If we're dropping a label to the constant pool, make sure we
3905      don't delete it.  */
3906   if (GET_CODE (x) == LABEL_REF)
3907     LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3908 
3909   return copy_rtx (def);
3910 }
3911 
3912 /* Given a constant pool SYMBOL_REF, return the corresponding constant.  */
3913 
3914 rtx
get_pool_constant(const_rtx addr)3915 get_pool_constant (const_rtx addr)
3916 {
3917   return SYMBOL_REF_CONSTANT (addr)->constant;
3918 }
3919 
3920 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3921    and whether it has been output or not.  */
3922 
3923 rtx
get_pool_constant_mark(rtx addr,bool * pmarked)3924 get_pool_constant_mark (rtx addr, bool *pmarked)
3925 {
3926   struct constant_descriptor_rtx *desc;
3927 
3928   desc = SYMBOL_REF_CONSTANT (addr);
3929   *pmarked = (desc->mark != 0);
3930   return desc->constant;
3931 }
3932 
3933 /* Similar, return the mode.  */
3934 
3935 fixed_size_mode
get_pool_mode(const_rtx addr)3936 get_pool_mode (const_rtx addr)
3937 {
3938   return SYMBOL_REF_CONSTANT (addr)->mode;
3939 }
3940 
3941 /* Return TRUE if and only if the constant pool has no entries.  Note
3942    that even entries we might end up choosing not to emit are counted
3943    here, so there is the potential for missed optimizations.  */
3944 
3945 bool
constant_pool_empty_p(void)3946 constant_pool_empty_p (void)
3947 {
3948   return crtl->varasm.pool->first == NULL;
3949 }
3950 
3951 /* Worker function for output_constant_pool_1.  Emit assembly for X
3952    in MODE with known alignment ALIGN.  */
3953 
3954 static void
output_constant_pool_2(fixed_size_mode mode,rtx x,unsigned int align)3955 output_constant_pool_2 (fixed_size_mode mode, rtx x, unsigned int align)
3956 {
3957   switch (GET_MODE_CLASS (mode))
3958     {
3959     case MODE_FLOAT:
3960     case MODE_DECIMAL_FLOAT:
3961       {
3962 	gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3963 	assemble_real (*CONST_DOUBLE_REAL_VALUE (x),
3964 		       as_a <scalar_float_mode> (mode), align, false);
3965 	break;
3966       }
3967 
3968     case MODE_INT:
3969     case MODE_PARTIAL_INT:
3970     case MODE_FRACT:
3971     case MODE_UFRACT:
3972     case MODE_ACCUM:
3973     case MODE_UACCUM:
3974       assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3975       break;
3976 
3977     case MODE_VECTOR_BOOL:
3978       {
3979 	gcc_assert (GET_CODE (x) == CONST_VECTOR);
3980 
3981 	/* Pick the smallest integer mode that contains at least one
3982 	   whole element.  Often this is byte_mode and contains more
3983 	   than one element.  */
3984 	unsigned int nelts = GET_MODE_NUNITS (mode);
3985 	unsigned int elt_bits = GET_MODE_BITSIZE (mode) / nelts;
3986 	unsigned int int_bits = MAX (elt_bits, BITS_PER_UNIT);
3987 	scalar_int_mode int_mode = int_mode_for_size (int_bits, 0).require ();
3988 
3989 	/* Build the constant up one integer at a time.  */
3990 	unsigned int elts_per_int = int_bits / elt_bits;
3991 	for (unsigned int i = 0; i < nelts; i += elts_per_int)
3992 	  {
3993 	    unsigned HOST_WIDE_INT value = 0;
3994 	    unsigned int limit = MIN (nelts - i, elts_per_int);
3995 	    for (unsigned int j = 0; j < limit; ++j)
3996 	      if (INTVAL (CONST_VECTOR_ELT (x, i + j)) != 0)
3997 		value |= 1 << (j * elt_bits);
3998 	    output_constant_pool_2 (int_mode, gen_int_mode (value, int_mode),
3999 				    i != 0 ? MIN (align, int_bits) : align);
4000 	  }
4001 	break;
4002       }
4003     case MODE_VECTOR_FLOAT:
4004     case MODE_VECTOR_INT:
4005     case MODE_VECTOR_FRACT:
4006     case MODE_VECTOR_UFRACT:
4007     case MODE_VECTOR_ACCUM:
4008     case MODE_VECTOR_UACCUM:
4009       {
4010 	int i, units;
4011 	scalar_mode submode = GET_MODE_INNER (mode);
4012 	unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
4013 
4014 	gcc_assert (GET_CODE (x) == CONST_VECTOR);
4015 	units = GET_MODE_NUNITS (mode);
4016 
4017 	for (i = 0; i < units; i++)
4018 	  {
4019 	    rtx elt = CONST_VECTOR_ELT (x, i);
4020 	    output_constant_pool_2 (submode, elt, i ? subalign : align);
4021 	  }
4022       }
4023       break;
4024 
4025     default:
4026       gcc_unreachable ();
4027     }
4028 }
4029 
4030 /* Worker function for output_constant_pool.  Emit constant DESC,
4031    giving it ALIGN bits of alignment.  */
4032 
4033 static void
output_constant_pool_1(struct constant_descriptor_rtx * desc,unsigned int align)4034 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
4035 			unsigned int align)
4036 {
4037   rtx x, tmp;
4038 
4039   x = desc->constant;
4040 
4041   /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
4042      whose CODE_LABEL has been deleted.  This can occur if a jump table
4043      is eliminated by optimization.  If so, write a constant of zero
4044      instead.  Note that this can also happen by turning the
4045      CODE_LABEL into a NOTE.  */
4046   /* ??? This seems completely and utterly wrong.  Certainly it's
4047      not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
4048      functioning even with rtx_insn::deleted and friends.  */
4049 
4050   tmp = x;
4051   switch (GET_CODE (tmp))
4052     {
4053     case CONST:
4054       if (GET_CODE (XEXP (tmp, 0)) != PLUS
4055 	  || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
4056 	break;
4057       tmp = XEXP (XEXP (tmp, 0), 0);
4058       /* FALLTHRU  */
4059 
4060     case LABEL_REF:
4061       {
4062 	rtx_insn *insn = label_ref_label (tmp);
4063 	gcc_assert (!insn->deleted ());
4064 	gcc_assert (!NOTE_P (insn)
4065 		    || NOTE_KIND (insn) != NOTE_INSN_DELETED);
4066 	break;
4067       }
4068 
4069     default:
4070       break;
4071     }
4072 
4073 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
4074   ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
4075 				 align, desc->labelno, done);
4076 #endif
4077 
4078   assemble_align (align);
4079 
4080   /* Output the label.  */
4081   targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
4082 
4083   /* Output the data.
4084      Pass actual alignment value while emitting string constant to asm code
4085      as function 'output_constant_pool_1' explicitly passes the alignment as 1
4086      assuming that the data is already aligned which prevents the generation
4087      of fix-up table entries.  */
4088   output_constant_pool_2 (desc->mode, x, desc->align);
4089 
4090   /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
4091      sections have proper size.  */
4092   if (align > GET_MODE_BITSIZE (desc->mode)
4093       && in_section
4094       && (in_section->common.flags & SECTION_MERGE))
4095     assemble_align (align);
4096 
4097 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
4098  done:
4099 #endif
4100   return;
4101 }
4102 
4103 /* Recompute the offsets of entries in POOL, and the overall size of
4104    POOL.  Do this after calling mark_constant_pool to ensure that we
4105    are computing the offset values for the pool which we will actually
4106    emit.  */
4107 
4108 static void
recompute_pool_offsets(struct rtx_constant_pool * pool)4109 recompute_pool_offsets (struct rtx_constant_pool *pool)
4110 {
4111   struct constant_descriptor_rtx *desc;
4112   pool->offset = 0;
4113 
4114   for (desc = pool->first; desc ; desc = desc->next)
4115     if (desc->mark)
4116       {
4117 	  /* Recalculate offset.  */
4118 	unsigned int align = desc->align;
4119 	pool->offset += (align / BITS_PER_UNIT) - 1;
4120 	pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
4121 	desc->offset = pool->offset;
4122 	pool->offset += GET_MODE_SIZE (desc->mode);
4123       }
4124 }
4125 
4126 /* Mark all constants that are referenced by SYMBOL_REFs in X.
4127    Emit referenced deferred strings.  */
4128 
4129 static void
mark_constants_in_pattern(rtx insn)4130 mark_constants_in_pattern (rtx insn)
4131 {
4132   subrtx_iterator::array_type array;
4133   FOR_EACH_SUBRTX (iter, array, PATTERN (insn), ALL)
4134     {
4135       const_rtx x = *iter;
4136       if (GET_CODE (x) == SYMBOL_REF)
4137 	{
4138 	  if (CONSTANT_POOL_ADDRESS_P (x))
4139 	    {
4140 	      struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
4141 	      if (desc->mark == 0)
4142 		{
4143 		  desc->mark = 1;
4144 		  iter.substitute (desc->constant);
4145 		}
4146 	    }
4147 	  else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
4148 	    {
4149 	      tree decl = SYMBOL_REF_DECL (x);
4150 	      if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
4151 		{
4152 		  n_deferred_constants--;
4153 		  output_constant_def_contents (CONST_CAST_RTX (x));
4154 		}
4155 	    }
4156 	}
4157     }
4158 }
4159 
4160 /* Look through appropriate parts of INSN, marking all entries in the
4161    constant pool which are actually being used.  Entries that are only
4162    referenced by other constants are also marked as used.  Emit
4163    deferred strings that are used.  */
4164 
4165 static void
mark_constants(rtx_insn * insn)4166 mark_constants (rtx_insn *insn)
4167 {
4168   if (!INSN_P (insn))
4169     return;
4170 
4171   /* Insns may appear inside a SEQUENCE.  Only check the patterns of
4172      insns, not any notes that may be attached.  We don't want to mark
4173      a constant just because it happens to appear in a REG_EQUIV note.  */
4174   if (rtx_sequence *seq = dyn_cast <rtx_sequence *> (PATTERN (insn)))
4175     {
4176       int i, n = seq->len ();
4177       for (i = 0; i < n; ++i)
4178 	{
4179 	  rtx subinsn = seq->element (i);
4180 	  if (INSN_P (subinsn))
4181 	    mark_constants_in_pattern (subinsn);
4182 	}
4183     }
4184   else
4185     mark_constants_in_pattern (insn);
4186 }
4187 
4188 /* Look through the instructions for this function, and mark all the
4189    entries in POOL which are actually being used.  Emit deferred constants
4190    which have indeed been used.  */
4191 
4192 static void
mark_constant_pool(void)4193 mark_constant_pool (void)
4194 {
4195   rtx_insn *insn;
4196 
4197   if (!crtl->uses_const_pool && n_deferred_constants == 0)
4198     return;
4199 
4200   for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4201     mark_constants (insn);
4202 }
4203 
4204 /* Write all the constants in POOL.  */
4205 
4206 static void
output_constant_pool_contents(struct rtx_constant_pool * pool)4207 output_constant_pool_contents (struct rtx_constant_pool *pool)
4208 {
4209   struct constant_descriptor_rtx *desc;
4210 
4211   for (desc = pool->first; desc ; desc = desc->next)
4212     if (desc->mark)
4213       {
4214 	/* If the constant is part of an object_block, make sure that
4215 	   the constant has been positioned within its block, but do not
4216 	   write out its definition yet.  output_object_blocks will do
4217 	   that later.  */
4218 	if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
4219 	    && SYMBOL_REF_BLOCK (desc->sym))
4220 	  place_block_symbol (desc->sym);
4221 	else
4222 	  {
4223 	    switch_to_section (targetm.asm_out.select_rtx_section
4224 			       (desc->mode, desc->constant, desc->align));
4225 	    output_constant_pool_1 (desc, desc->align);
4226 	  }
4227       }
4228 }
4229 
4230 /* Mark all constants that are used in the current function, then write
4231    out the function's private constant pool.  */
4232 
4233 static void
output_constant_pool(const char * fnname ATTRIBUTE_UNUSED,tree fndecl ATTRIBUTE_UNUSED)4234 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
4235 		      tree fndecl ATTRIBUTE_UNUSED)
4236 {
4237   struct rtx_constant_pool *pool = crtl->varasm.pool;
4238 
4239   /* It is possible for gcc to call force_const_mem and then to later
4240      discard the instructions which refer to the constant.  In such a
4241      case we do not need to output the constant.  */
4242   mark_constant_pool ();
4243 
4244   /* Having marked the constant pool entries we'll actually emit, we
4245      now need to rebuild the offset information, which may have become
4246      stale.  */
4247   recompute_pool_offsets (pool);
4248 
4249 #ifdef ASM_OUTPUT_POOL_PROLOGUE
4250   ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
4251 #endif
4252 
4253   output_constant_pool_contents (pool);
4254 
4255 #ifdef ASM_OUTPUT_POOL_EPILOGUE
4256   ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
4257 #endif
4258 }
4259 
4260 /* Write the contents of the shared constant pool.  */
4261 
4262 void
output_shared_constant_pool(void)4263 output_shared_constant_pool (void)
4264 {
4265   output_constant_pool_contents (shared_constant_pool);
4266 }
4267 
4268 /* Determine what kind of relocations EXP may need.  */
4269 
4270 int
compute_reloc_for_constant(tree exp)4271 compute_reloc_for_constant (tree exp)
4272 {
4273   int reloc = 0, reloc2;
4274   tree tem;
4275 
4276   switch (TREE_CODE (exp))
4277     {
4278     case ADDR_EXPR:
4279     case FDESC_EXPR:
4280       /* Go inside any operations that get_inner_reference can handle and see
4281 	 if what's inside is a constant: no need to do anything here for
4282 	 addresses of variables or functions.  */
4283       for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4284 	   tem = TREE_OPERAND (tem, 0))
4285 	;
4286 
4287       if (TREE_CODE (tem) == MEM_REF
4288 	  && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4289 	{
4290 	  reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4291 	  break;
4292 	}
4293 
4294       if (!targetm.binds_local_p (tem))
4295 	reloc |= 2;
4296       else
4297 	reloc |= 1;
4298       break;
4299 
4300     case PLUS_EXPR:
4301     case POINTER_PLUS_EXPR:
4302       reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4303       reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4304       break;
4305 
4306     case MINUS_EXPR:
4307       reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4308       reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4309       /* The difference of two local labels is computable at link time.  */
4310       if (reloc == 1 && reloc2 == 1)
4311 	reloc = 0;
4312       else
4313 	reloc |= reloc2;
4314       break;
4315 
4316     CASE_CONVERT:
4317     case VIEW_CONVERT_EXPR:
4318       reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4319       break;
4320 
4321     case CONSTRUCTOR:
4322       {
4323 	unsigned HOST_WIDE_INT idx;
4324 	FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4325 	  if (tem != 0)
4326 	    reloc |= compute_reloc_for_constant (tem);
4327       }
4328       break;
4329 
4330     default:
4331       break;
4332     }
4333   return reloc;
4334 }
4335 
4336 /* Find all the constants whose addresses are referenced inside of EXP,
4337    and make sure assembler code with a label has been output for each one.
4338    Indicate whether an ADDR_EXPR has been encountered.  */
4339 
4340 static void
output_addressed_constants(tree exp)4341 output_addressed_constants (tree exp)
4342 {
4343   tree tem;
4344 
4345   switch (TREE_CODE (exp))
4346     {
4347     case ADDR_EXPR:
4348     case FDESC_EXPR:
4349       /* Go inside any operations that get_inner_reference can handle and see
4350 	 if what's inside is a constant: no need to do anything here for
4351 	 addresses of variables or functions.  */
4352       for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4353 	   tem = TREE_OPERAND (tem, 0))
4354 	;
4355 
4356       /* If we have an initialized CONST_DECL, retrieve the initializer.  */
4357       if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4358 	tem = DECL_INITIAL (tem);
4359 
4360       if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4361 	output_constant_def (tem, 0);
4362 
4363       if (TREE_CODE (tem) == MEM_REF)
4364 	output_addressed_constants (TREE_OPERAND (tem, 0));
4365       break;
4366 
4367     case PLUS_EXPR:
4368     case POINTER_PLUS_EXPR:
4369     case MINUS_EXPR:
4370       output_addressed_constants (TREE_OPERAND (exp, 1));
4371       gcc_fallthrough ();
4372 
4373     CASE_CONVERT:
4374     case VIEW_CONVERT_EXPR:
4375       output_addressed_constants (TREE_OPERAND (exp, 0));
4376       break;
4377 
4378     case CONSTRUCTOR:
4379       {
4380 	unsigned HOST_WIDE_INT idx;
4381 	FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4382 	  if (tem != 0)
4383 	    output_addressed_constants (tem);
4384       }
4385       break;
4386 
4387     default:
4388       break;
4389     }
4390 }
4391 
4392 /* Whether a constructor CTOR is a valid static constant initializer if all
4393    its elements are.  This used to be internal to initializer_constant_valid_p
4394    and has been exposed to let other functions like categorize_ctor_elements
4395    evaluate the property while walking a constructor for other purposes.  */
4396 
4397 bool
constructor_static_from_elts_p(const_tree ctor)4398 constructor_static_from_elts_p (const_tree ctor)
4399 {
4400   return (TREE_CONSTANT (ctor)
4401 	  && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4402 	      || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4403 	      || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4404 }
4405 
4406 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4407 					    tree *cache);
4408 
4409 /* A subroutine of initializer_constant_valid_p.  VALUE is a MINUS_EXPR,
4410    PLUS_EXPR or POINTER_PLUS_EXPR.  This looks for cases of VALUE
4411    which are valid when ENDTYPE is an integer of any size; in
4412    particular, this does not accept a pointer minus a constant.  This
4413    returns null_pointer_node if the VALUE is an absolute constant
4414    which can be used to initialize a static variable.  Otherwise it
4415    returns NULL.  */
4416 
4417 static tree
narrowing_initializer_constant_valid_p(tree value,tree endtype,tree * cache)4418 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4419 {
4420   tree op0, op1;
4421 
4422   if (!INTEGRAL_TYPE_P (endtype))
4423     return NULL_TREE;
4424 
4425   op0 = TREE_OPERAND (value, 0);
4426   op1 = TREE_OPERAND (value, 1);
4427 
4428   /* Like STRIP_NOPS except allow the operand mode to widen.  This
4429      works around a feature of fold that simplifies (int)(p1 - p2) to
4430      ((int)p1 - (int)p2) under the theory that the narrower operation
4431      is cheaper.  */
4432 
4433   while (CONVERT_EXPR_P (op0)
4434 	 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4435     {
4436       tree inner = TREE_OPERAND (op0, 0);
4437       if (inner == error_mark_node
4438 	  || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4439 	  || (GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (op0)))
4440 	      > GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (inner)))))
4441 	break;
4442       op0 = inner;
4443     }
4444 
4445   while (CONVERT_EXPR_P (op1)
4446 	 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4447     {
4448       tree inner = TREE_OPERAND (op1, 0);
4449       if (inner == error_mark_node
4450 	  || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4451 	  || (GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (op1)))
4452 	      > GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (inner)))))
4453 	break;
4454       op1 = inner;
4455     }
4456 
4457   op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4458   if (!op0)
4459     return NULL_TREE;
4460 
4461   op1 = initializer_constant_valid_p_1 (op1, endtype,
4462 					cache ? cache + 2 : NULL);
4463   /* Both initializers must be known.  */
4464   if (op1)
4465     {
4466       if (op0 == op1
4467 	  && (op0 == null_pointer_node
4468 	      || TREE_CODE (value) == MINUS_EXPR))
4469 	return null_pointer_node;
4470 
4471       /* Support differences between labels.  */
4472       if (TREE_CODE (op0) == LABEL_DECL
4473 	  && TREE_CODE (op1) == LABEL_DECL)
4474 	return null_pointer_node;
4475 
4476       if (TREE_CODE (op0) == STRING_CST
4477 	  && TREE_CODE (op1) == STRING_CST
4478 	  && operand_equal_p (op0, op1, 1))
4479 	return null_pointer_node;
4480     }
4481 
4482   return NULL_TREE;
4483 }
4484 
4485 /* Helper function of initializer_constant_valid_p.
4486    Return nonzero if VALUE is a valid constant-valued expression
4487    for use in initializing a static variable; one that can be an
4488    element of a "constant" initializer.
4489 
4490    Return null_pointer_node if the value is absolute;
4491    if it is relocatable, return the variable that determines the relocation.
4492    We assume that VALUE has been folded as much as possible;
4493    therefore, we do not need to check for such things as
4494    arithmetic-combinations of integers.
4495 
4496    Use CACHE (pointer to 2 tree values) for caching if non-NULL.  */
4497 
4498 static tree
initializer_constant_valid_p_1(tree value,tree endtype,tree * cache)4499 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4500 {
4501   tree ret;
4502 
4503   switch (TREE_CODE (value))
4504     {
4505     case CONSTRUCTOR:
4506       if (constructor_static_from_elts_p (value))
4507 	{
4508 	  unsigned HOST_WIDE_INT idx;
4509 	  tree elt;
4510 	  bool absolute = true;
4511 
4512 	  if (cache && cache[0] == value)
4513 	    return cache[1];
4514 	  FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4515 	    {
4516 	      tree reloc;
4517 	      reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4518 						      NULL);
4519 	      if (!reloc
4520 		  /* An absolute value is required with reverse SSO.  */
4521 		  || (reloc != null_pointer_node
4522 		      && TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (value))
4523 		      && !AGGREGATE_TYPE_P (TREE_TYPE (elt))))
4524 		{
4525 		  if (cache)
4526 		    {
4527 		      cache[0] = value;
4528 		      cache[1] = NULL_TREE;
4529 		    }
4530 		  return NULL_TREE;
4531 		}
4532 	      if (reloc != null_pointer_node)
4533 		absolute = false;
4534 	    }
4535 	  /* For a non-absolute relocation, there is no single
4536 	     variable that can be "the variable that determines the
4537 	     relocation."  */
4538 	  if (cache)
4539 	    {
4540 	      cache[0] = value;
4541 	      cache[1] = absolute ? null_pointer_node : error_mark_node;
4542 	    }
4543 	  return absolute ? null_pointer_node : error_mark_node;
4544 	}
4545 
4546       return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4547 
4548     case INTEGER_CST:
4549     case VECTOR_CST:
4550     case REAL_CST:
4551     case FIXED_CST:
4552     case STRING_CST:
4553     case COMPLEX_CST:
4554       return null_pointer_node;
4555 
4556     case ADDR_EXPR:
4557     case FDESC_EXPR:
4558       {
4559 	tree op0 = staticp (TREE_OPERAND (value, 0));
4560 	if (op0)
4561 	  {
4562 	    /* "&(*a).f" is like unto pointer arithmetic.  If "a" turns out
4563 	       to be a constant, this is old-skool offsetof-like nonsense.  */
4564 	    if (TREE_CODE (op0) == INDIRECT_REF
4565 		&& TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4566 	      return null_pointer_node;
4567 	    /* Taking the address of a nested function involves a trampoline,
4568 	       unless we don't need or want one.  */
4569 	    if (TREE_CODE (op0) == FUNCTION_DECL
4570 		&& DECL_STATIC_CHAIN (op0)
4571 		&& !TREE_NO_TRAMPOLINE (value))
4572 	      return NULL_TREE;
4573 	    /* "&{...}" requires a temporary to hold the constructed
4574 	       object.  */
4575 	    if (TREE_CODE (op0) == CONSTRUCTOR)
4576 	      return NULL_TREE;
4577 	  }
4578 	return op0;
4579       }
4580 
4581     case NON_LVALUE_EXPR:
4582       return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4583 					     endtype, cache);
4584 
4585     case VIEW_CONVERT_EXPR:
4586       {
4587 	tree src = TREE_OPERAND (value, 0);
4588 	tree src_type = TREE_TYPE (src);
4589 	tree dest_type = TREE_TYPE (value);
4590 
4591 	/* Allow view-conversions from aggregate to non-aggregate type only
4592 	   if the bit pattern is fully preserved afterwards; otherwise, the
4593 	   RTL expander won't be able to apply a subsequent transformation
4594 	   to the underlying constructor.  */
4595 	if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4596 	  {
4597 	    if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4598 	      return initializer_constant_valid_p_1 (src, endtype, cache);
4599 	    else
4600 	      return NULL_TREE;
4601 	  }
4602 
4603 	/* Allow all other kinds of view-conversion.  */
4604 	return initializer_constant_valid_p_1 (src, endtype, cache);
4605       }
4606 
4607     CASE_CONVERT:
4608       {
4609 	tree src = TREE_OPERAND (value, 0);
4610 	tree src_type = TREE_TYPE (src);
4611 	tree dest_type = TREE_TYPE (value);
4612 
4613 	/* Allow conversions between pointer types, floating-point
4614 	   types, and offset types.  */
4615 	if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4616 	    || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4617 	    || (TREE_CODE (dest_type) == OFFSET_TYPE
4618 		&& TREE_CODE (src_type) == OFFSET_TYPE))
4619 	  return initializer_constant_valid_p_1 (src, endtype, cache);
4620 
4621 	/* Allow length-preserving conversions between integer types.  */
4622 	if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4623 	    && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4624 	  return initializer_constant_valid_p_1 (src, endtype, cache);
4625 
4626 	/* Allow conversions between other integer types only if
4627 	   explicit value.  Don't allow sign-extension to a type larger
4628 	   than word and pointer, there aren't relocations that would
4629 	   allow to sign extend it to a wider type.  */
4630 	if (INTEGRAL_TYPE_P (dest_type)
4631 	    && INTEGRAL_TYPE_P (src_type)
4632 	    && (TYPE_UNSIGNED (src_type)
4633 		|| TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type)
4634 		|| TYPE_PRECISION (dest_type) <= BITS_PER_WORD
4635 		|| TYPE_PRECISION (dest_type) <= POINTER_SIZE))
4636 	  {
4637 	    tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4638 	    if (inner == null_pointer_node)
4639 	      return null_pointer_node;
4640 	    break;
4641 	  }
4642 
4643 	/* Allow (int) &foo provided int is as wide as a pointer.  */
4644 	if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4645 	    && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4646 	  return initializer_constant_valid_p_1 (src, endtype, cache);
4647 
4648 	/* Likewise conversions from int to pointers, but also allow
4649 	   conversions from 0.  */
4650 	if ((POINTER_TYPE_P (dest_type)
4651 	     || TREE_CODE (dest_type) == OFFSET_TYPE)
4652 	    && INTEGRAL_TYPE_P (src_type))
4653 	  {
4654 	    if (TREE_CODE (src) == INTEGER_CST
4655 		&& TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4656 	      return null_pointer_node;
4657 	    if (integer_zerop (src))
4658 	      return null_pointer_node;
4659 	    else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4660 	      return initializer_constant_valid_p_1 (src, endtype, cache);
4661 	  }
4662 
4663 	/* Allow conversions to struct or union types if the value
4664 	   inside is okay.  */
4665 	if (TREE_CODE (dest_type) == RECORD_TYPE
4666 	    || TREE_CODE (dest_type) == UNION_TYPE)
4667 	  return initializer_constant_valid_p_1 (src, endtype, cache);
4668       }
4669       break;
4670 
4671     case POINTER_PLUS_EXPR:
4672     case PLUS_EXPR:
4673       /* Any valid floating-point constants will have been folded by now;
4674 	 with -frounding-math we hit this with addition of two constants.  */
4675       if (TREE_CODE (endtype) == REAL_TYPE)
4676 	return NULL_TREE;
4677       if (cache && cache[0] == value)
4678 	return cache[1];
4679       if (! INTEGRAL_TYPE_P (endtype)
4680 	  || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4681 	{
4682 	  tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4683 	  tree valid0
4684 	    = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4685 					      endtype, ncache);
4686 	  tree valid1
4687 	    = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4688 					      endtype, ncache + 2);
4689 	  /* If either term is absolute, use the other term's relocation.  */
4690 	  if (valid0 == null_pointer_node)
4691 	    ret = valid1;
4692 	  else if (valid1 == null_pointer_node)
4693 	    ret = valid0;
4694 	  /* Support narrowing pointer differences.  */
4695 	  else
4696 	    ret = narrowing_initializer_constant_valid_p (value, endtype,
4697 							  ncache);
4698 	}
4699       else
4700       /* Support narrowing pointer differences.  */
4701 	ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4702       if (cache)
4703 	{
4704 	  cache[0] = value;
4705 	  cache[1] = ret;
4706 	}
4707       return ret;
4708 
4709     case POINTER_DIFF_EXPR:
4710     case MINUS_EXPR:
4711       if (TREE_CODE (endtype) == REAL_TYPE)
4712 	return NULL_TREE;
4713       if (cache && cache[0] == value)
4714 	return cache[1];
4715       if (! INTEGRAL_TYPE_P (endtype)
4716 	  || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4717 	{
4718 	  tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4719 	  tree valid0
4720 	    = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4721 					      endtype, ncache);
4722 	  tree valid1
4723 	    = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4724 					      endtype, ncache + 2);
4725 	  /* Win if second argument is absolute.  */
4726 	  if (valid1 == null_pointer_node)
4727 	    ret = valid0;
4728 	  /* Win if both arguments have the same relocation.
4729 	     Then the value is absolute.  */
4730 	  else if (valid0 == valid1 && valid0 != 0)
4731 	    ret = null_pointer_node;
4732 	  /* Since GCC guarantees that string constants are unique in the
4733 	     generated code, a subtraction between two copies of the same
4734 	     constant string is absolute.  */
4735 	  else if (valid0 && TREE_CODE (valid0) == STRING_CST
4736 		   && valid1 && TREE_CODE (valid1) == STRING_CST
4737 		   && operand_equal_p (valid0, valid1, 1))
4738 	    ret = null_pointer_node;
4739 	  /* Support narrowing differences.  */
4740 	  else
4741 	    ret = narrowing_initializer_constant_valid_p (value, endtype,
4742 							  ncache);
4743 	}
4744       else
4745 	/* Support narrowing differences.  */
4746 	ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4747       if (cache)
4748 	{
4749 	  cache[0] = value;
4750 	  cache[1] = ret;
4751 	}
4752       return ret;
4753 
4754     default:
4755       break;
4756     }
4757 
4758   return NULL_TREE;
4759 }
4760 
4761 /* Return nonzero if VALUE is a valid constant-valued expression
4762    for use in initializing a static variable; one that can be an
4763    element of a "constant" initializer.
4764 
4765    Return null_pointer_node if the value is absolute;
4766    if it is relocatable, return the variable that determines the relocation.
4767    We assume that VALUE has been folded as much as possible;
4768    therefore, we do not need to check for such things as
4769    arithmetic-combinations of integers.  */
4770 tree
initializer_constant_valid_p(tree value,tree endtype,bool reverse)4771 initializer_constant_valid_p (tree value, tree endtype, bool reverse)
4772 {
4773   tree reloc = initializer_constant_valid_p_1 (value, endtype, NULL);
4774 
4775   /* An absolute value is required with reverse storage order.  */
4776   if (reloc
4777       && reloc != null_pointer_node
4778       && reverse
4779       && !AGGREGATE_TYPE_P (endtype)
4780       && !VECTOR_TYPE_P (endtype))
4781     reloc = NULL_TREE;
4782 
4783   return reloc;
4784 }
4785 
4786 /* Return true if VALUE is a valid constant-valued expression
4787    for use in initializing a static bit-field; one that can be
4788    an element of a "constant" initializer.  */
4789 
4790 bool
initializer_constant_valid_for_bitfield_p(tree value)4791 initializer_constant_valid_for_bitfield_p (tree value)
4792 {
4793   /* For bitfields we support integer constants or possibly nested aggregates
4794      of such.  */
4795   switch (TREE_CODE (value))
4796     {
4797     case CONSTRUCTOR:
4798       {
4799 	unsigned HOST_WIDE_INT idx;
4800 	tree elt;
4801 
4802 	FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4803 	  if (!initializer_constant_valid_for_bitfield_p (elt))
4804 	    return false;
4805 	return true;
4806       }
4807 
4808     case INTEGER_CST:
4809     case REAL_CST:
4810       return true;
4811 
4812     case VIEW_CONVERT_EXPR:
4813     case NON_LVALUE_EXPR:
4814       return
4815 	initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4816 
4817     default:
4818       break;
4819     }
4820 
4821   return false;
4822 }
4823 
4824 /* Check if a STRING_CST fits into the field.
4825    Tolerate only the case when the NUL termination
4826    does not fit into the field.   */
4827 
4828 static bool
check_string_literal(tree string,unsigned HOST_WIDE_INT size)4829 check_string_literal (tree string, unsigned HOST_WIDE_INT size)
4830 {
4831   tree type = TREE_TYPE (string);
4832   tree eltype = TREE_TYPE (type);
4833   unsigned HOST_WIDE_INT elts = tree_to_uhwi (TYPE_SIZE_UNIT (eltype));
4834   unsigned HOST_WIDE_INT mem_size = tree_to_uhwi (TYPE_SIZE_UNIT (type));
4835   int len = TREE_STRING_LENGTH (string);
4836 
4837   if (elts != 1 && elts != 2 && elts != 4)
4838     return false;
4839   if (len < 0 || len % elts != 0)
4840     return false;
4841   if (size < (unsigned)len)
4842     return false;
4843   if (mem_size != size)
4844     return false;
4845   return true;
4846 }
4847 
4848 /* output_constructor outer state of relevance in recursive calls, typically
4849    for nested aggregate bitfields.  */
4850 
4851 struct oc_outer_state {
4852   unsigned int bit_offset;  /* current position in ...  */
4853   int byte;                 /* ... the outer byte buffer.  */
4854 };
4855 
4856 static unsigned HOST_WIDE_INT
4857 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int, bool,
4858 		    oc_outer_state *);
4859 
4860 /* Output assembler code for constant EXP, with no label.
4861    This includes the pseudo-op such as ".int" or ".byte", and a newline.
4862    Assumes output_addressed_constants has been done on EXP already.
4863 
4864    Generate at least SIZE bytes of assembler data, padding at the end
4865    with zeros if necessary.  SIZE must always be specified.  The returned
4866    value is the actual number of bytes of assembler data generated, which
4867    may be bigger than SIZE if the object contains a variable length field.
4868 
4869    SIZE is important for structure constructors,
4870    since trailing members may have been omitted from the constructor.
4871    It is also important for initialization of arrays from string constants
4872    since the full length of the string constant might not be wanted.
4873    It is also needed for initialization of unions, where the initializer's
4874    type is just one member, and that may not be as long as the union.
4875 
4876    There a case in which we would fail to output exactly SIZE bytes:
4877    for a structure constructor that wants to produce more than SIZE bytes.
4878    But such constructors will never be generated for any possible input.
4879 
4880    ALIGN is the alignment of the data in bits.
4881 
4882    If REVERSE is true, EXP is output in reverse storage order.  */
4883 
4884 static unsigned HOST_WIDE_INT
output_constant(tree exp,unsigned HOST_WIDE_INT size,unsigned int align,bool reverse,bool merge_strings)4885 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align,
4886 		 bool reverse, bool merge_strings)
4887 {
4888   enum tree_code code;
4889   unsigned HOST_WIDE_INT thissize;
4890   rtx cst;
4891 
4892   if (size == 0 || flag_syntax_only)
4893     return size;
4894 
4895   /* See if we're trying to initialize a pointer in a non-default mode
4896      to the address of some declaration somewhere.  If the target says
4897      the mode is valid for pointers, assume the target has a way of
4898      resolving it.  */
4899   if (TREE_CODE (exp) == NOP_EXPR
4900       && POINTER_TYPE_P (TREE_TYPE (exp))
4901       && targetm.addr_space.valid_pointer_mode
4902 	   (SCALAR_INT_TYPE_MODE (TREE_TYPE (exp)),
4903 	    TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4904     {
4905       tree saved_type = TREE_TYPE (exp);
4906 
4907       /* Peel off any intermediate conversions-to-pointer for valid
4908 	 pointer modes.  */
4909       while (TREE_CODE (exp) == NOP_EXPR
4910 	     && POINTER_TYPE_P (TREE_TYPE (exp))
4911 	     && targetm.addr_space.valid_pointer_mode
4912 		  (SCALAR_INT_TYPE_MODE (TREE_TYPE (exp)),
4913 		   TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4914 	exp = TREE_OPERAND (exp, 0);
4915 
4916       /* If what we're left with is the address of something, we can
4917 	 convert the address to the final type and output it that
4918 	 way.  */
4919       if (TREE_CODE (exp) == ADDR_EXPR)
4920 	exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4921       /* Likewise for constant ints.  */
4922       else if (TREE_CODE (exp) == INTEGER_CST)
4923 	exp = fold_convert (saved_type, exp);
4924 
4925     }
4926 
4927   /* Eliminate any conversions since we'll be outputting the underlying
4928      constant.  */
4929   while (CONVERT_EXPR_P (exp)
4930 	 || TREE_CODE (exp) == NON_LVALUE_EXPR
4931 	 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4932     {
4933       HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4934       HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4935 
4936       /* Make sure eliminating the conversion is really a no-op, except with
4937 	 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4938 	 union types to allow for Ada unchecked unions.  */
4939       if (type_size > op_size
4940 	  && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4941 	  && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4942 	/* Keep the conversion. */
4943 	break;
4944       else
4945 	exp = TREE_OPERAND (exp, 0);
4946     }
4947 
4948   code = TREE_CODE (TREE_TYPE (exp));
4949   thissize = int_size_in_bytes (TREE_TYPE (exp));
4950 
4951   /* Allow a constructor with no elements for any data type.
4952      This means to fill the space with zeros.  */
4953   if (TREE_CODE (exp) == CONSTRUCTOR
4954       && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4955     {
4956       assemble_zeros (size);
4957       return size;
4958     }
4959 
4960   if (TREE_CODE (exp) == FDESC_EXPR)
4961     {
4962 #ifdef ASM_OUTPUT_FDESC
4963       HOST_WIDE_INT part = tree_to_shwi (TREE_OPERAND (exp, 1));
4964       tree decl = TREE_OPERAND (exp, 0);
4965       ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4966 #else
4967       gcc_unreachable ();
4968 #endif
4969       return size;
4970     }
4971 
4972   /* Now output the underlying data.  If we've handling the padding, return.
4973      Otherwise, break and ensure SIZE is the size written.  */
4974   switch (code)
4975     {
4976     case BOOLEAN_TYPE:
4977     case INTEGER_TYPE:
4978     case ENUMERAL_TYPE:
4979     case POINTER_TYPE:
4980     case REFERENCE_TYPE:
4981     case OFFSET_TYPE:
4982     case FIXED_POINT_TYPE:
4983     case NULLPTR_TYPE:
4984       cst = expand_expr (exp, NULL_RTX, VOIDmode, EXPAND_INITIALIZER);
4985       if (reverse)
4986 	cst = flip_storage_order (TYPE_MODE (TREE_TYPE (exp)), cst);
4987       if (!assemble_integer (cst, MIN (size, thissize), align, 0))
4988 	error ("initializer for integer/fixed-point value is too complicated");
4989       break;
4990 
4991     case REAL_TYPE:
4992       if (TREE_CODE (exp) != REAL_CST)
4993 	error ("initializer for floating value is not a floating constant");
4994       else
4995 	assemble_real (TREE_REAL_CST (exp),
4996 		       SCALAR_FLOAT_TYPE_MODE (TREE_TYPE (exp)),
4997 		       align, reverse);
4998       break;
4999 
5000     case COMPLEX_TYPE:
5001       output_constant (TREE_REALPART (exp), thissize / 2, align,
5002 		       reverse, false);
5003       output_constant (TREE_IMAGPART (exp), thissize / 2,
5004 		       min_align (align, BITS_PER_UNIT * (thissize / 2)),
5005 		       reverse, false);
5006       break;
5007 
5008     case ARRAY_TYPE:
5009     case VECTOR_TYPE:
5010       switch (TREE_CODE (exp))
5011 	{
5012 	case CONSTRUCTOR:
5013 	  return output_constructor (exp, size, align, reverse, NULL);
5014 	case STRING_CST:
5015 	  thissize = (unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp);
5016 	  if (merge_strings
5017 	      && (thissize == 0
5018 		  || TREE_STRING_POINTER (exp) [thissize - 1] != '\0'))
5019 	    thissize++;
5020 	  gcc_checking_assert (check_string_literal (exp, size));
5021 	  assemble_string (TREE_STRING_POINTER (exp), thissize);
5022 	  break;
5023 	case VECTOR_CST:
5024 	  {
5025 	    scalar_mode inner = SCALAR_TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
5026 	    unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
5027 	    int elt_size = GET_MODE_SIZE (inner);
5028 	    output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align,
5029 			     reverse, false);
5030 	    thissize = elt_size;
5031 	    /* Static constants must have a fixed size.  */
5032 	    unsigned int nunits = VECTOR_CST_NELTS (exp).to_constant ();
5033 	    for (unsigned int i = 1; i < nunits; i++)
5034 	      {
5035 		output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign,
5036 				 reverse, false);
5037 		thissize += elt_size;
5038 	      }
5039 	    break;
5040 	  }
5041 	default:
5042 	  gcc_unreachable ();
5043 	}
5044       break;
5045 
5046     case RECORD_TYPE:
5047     case UNION_TYPE:
5048       gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
5049       return output_constructor (exp, size, align, reverse, NULL);
5050 
5051     case ERROR_MARK:
5052       return 0;
5053 
5054     default:
5055       gcc_unreachable ();
5056     }
5057 
5058   if (size > thissize)
5059     assemble_zeros (size - thissize);
5060 
5061   return size;
5062 }
5063 
5064 /* Subroutine of output_constructor, used for computing the size of
5065    arrays of unspecified length.  VAL must be a CONSTRUCTOR of an array
5066    type with an unspecified upper bound.  */
5067 
5068 static unsigned HOST_WIDE_INT
array_size_for_constructor(tree val)5069 array_size_for_constructor (tree val)
5070 {
5071   tree max_index;
5072   unsigned HOST_WIDE_INT cnt;
5073   tree index, value, tmp;
5074   offset_int i;
5075 
5076   /* This code used to attempt to handle string constants that are not
5077      arrays of single-bytes, but nothing else does, so there's no point in
5078      doing it here.  */
5079   if (TREE_CODE (val) == STRING_CST)
5080     return TREE_STRING_LENGTH (val);
5081 
5082   max_index = NULL_TREE;
5083   FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
5084     {
5085       if (TREE_CODE (index) == RANGE_EXPR)
5086 	index = TREE_OPERAND (index, 1);
5087       if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
5088 	max_index = index;
5089     }
5090 
5091   if (max_index == NULL_TREE)
5092     return 0;
5093 
5094   /* Compute the total number of array elements.  */
5095   tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
5096   i = wi::to_offset (max_index) - wi::to_offset (tmp) + 1;
5097 
5098   /* Multiply by the array element unit size to find number of bytes.  */
5099   i *= wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
5100 
5101   gcc_assert (wi::fits_uhwi_p (i));
5102   return i.to_uhwi ();
5103 }
5104 
5105 /* Other datastructures + helpers for output_constructor.  */
5106 
5107 /* output_constructor local state to support interaction with helpers.  */
5108 
5109 struct oc_local_state {
5110 
5111   /* Received arguments.  */
5112   tree exp;                     /* Constructor expression.  */
5113   tree type;                    /* Type of constructor expression.  */
5114   unsigned HOST_WIDE_INT size;  /* # bytes to output - pad if necessary.  */
5115   unsigned int align;           /* Known initial alignment.  */
5116   tree min_index;               /* Lower bound if specified for an array.  */
5117 
5118   /* Output processing state.  */
5119   HOST_WIDE_INT total_bytes;  /* # bytes output so far / current position.  */
5120   int byte;                   /* Part of a bitfield byte yet to be output.  */
5121   int last_relative_index;    /* Implicit or explicit index of the last
5122 				 array element output within a bitfield.  */
5123   bool byte_buffer_in_use;    /* Whether BYTE is in use.  */
5124   bool reverse;               /* Whether reverse storage order is in use.  */
5125 
5126   /* Current element.  */
5127   tree field;      /* Current field decl in a record.  */
5128   tree val;        /* Current element value.  */
5129   tree index;      /* Current element index.  */
5130 
5131 };
5132 
5133 /* Helper for output_constructor.  From the current LOCAL state, output a
5134    RANGE_EXPR element.  */
5135 
5136 static void
output_constructor_array_range(oc_local_state * local)5137 output_constructor_array_range (oc_local_state *local)
5138 {
5139   /* Perform the index calculation in modulo arithmetic but
5140      sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
5141      but we are using an unsigned sizetype.  */
5142   unsigned prec = TYPE_PRECISION (sizetype);
5143   offset_int idx = wi::sext (wi::to_offset (TREE_OPERAND (local->index, 0))
5144 			     - wi::to_offset (local->min_index), prec);
5145   tree valtype = TREE_TYPE (local->val);
5146   HOST_WIDE_INT fieldpos
5147     = (idx * wi::to_offset (TYPE_SIZE_UNIT (valtype))).to_short_addr ();
5148 
5149   /* Advance to offset of this element.  */
5150   if (fieldpos > local->total_bytes)
5151     {
5152       assemble_zeros (fieldpos - local->total_bytes);
5153       local->total_bytes = fieldpos;
5154     }
5155   else
5156     /* Must not go backwards.  */
5157     gcc_assert (fieldpos == local->total_bytes);
5158 
5159   unsigned HOST_WIDE_INT fieldsize
5160     = int_size_in_bytes (TREE_TYPE (local->type));
5161 
5162   HOST_WIDE_INT lo_index
5163     = tree_to_shwi (TREE_OPERAND (local->index, 0));
5164   HOST_WIDE_INT hi_index
5165     = tree_to_shwi (TREE_OPERAND (local->index, 1));
5166   HOST_WIDE_INT index;
5167 
5168   unsigned int align2
5169     = min_align (local->align, fieldsize * BITS_PER_UNIT);
5170 
5171   for (index = lo_index; index <= hi_index; index++)
5172     {
5173       /* Output the element's initial value.  */
5174       if (local->val == NULL_TREE)
5175 	assemble_zeros (fieldsize);
5176       else
5177 	fieldsize = output_constant (local->val, fieldsize, align2,
5178 				     local->reverse, false);
5179 
5180       /* Count its size.  */
5181       local->total_bytes += fieldsize;
5182     }
5183 }
5184 
5185 /* Helper for output_constructor.  From the current LOCAL state, output a
5186    field element that is not true bitfield or part of an outer one.  */
5187 
5188 static void
output_constructor_regular_field(oc_local_state * local)5189 output_constructor_regular_field (oc_local_state *local)
5190 {
5191   /* Field size and position.  Since this structure is static, we know the
5192      positions are constant.  */
5193   unsigned HOST_WIDE_INT fieldsize;
5194   HOST_WIDE_INT fieldpos;
5195 
5196   unsigned int align2;
5197 
5198   /* Output any buffered-up bit-fields preceding this element.  */
5199   if (local->byte_buffer_in_use)
5200     {
5201       assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5202       local->total_bytes++;
5203       local->byte_buffer_in_use = false;
5204     }
5205 
5206   if (local->index != NULL_TREE)
5207     {
5208       /* Perform the index calculation in modulo arithmetic but
5209 	 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
5210 	 but we are using an unsigned sizetype.  */
5211       unsigned prec = TYPE_PRECISION (sizetype);
5212       offset_int idx = wi::sext (wi::to_offset (local->index)
5213 				 - wi::to_offset (local->min_index), prec);
5214       fieldpos = (idx * wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (local->val))))
5215 	.to_short_addr ();
5216     }
5217   else if (local->field != NULL_TREE)
5218     fieldpos = int_byte_position (local->field);
5219   else
5220     fieldpos = 0;
5221 
5222   /* Advance to offset of this element.
5223      Note no alignment needed in an array, since that is guaranteed
5224      if each element has the proper size.  */
5225   if (local->field != NULL_TREE || local->index != NULL_TREE)
5226     {
5227       if (fieldpos > local->total_bytes)
5228 	{
5229 	  assemble_zeros (fieldpos - local->total_bytes);
5230 	  local->total_bytes = fieldpos;
5231 	}
5232       else
5233 	/* Must not go backwards.  */
5234 	gcc_assert (fieldpos == local->total_bytes);
5235     }
5236 
5237   /* Find the alignment of this element.  */
5238   align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
5239 
5240   /* Determine size this element should occupy.  */
5241   if (local->field)
5242     {
5243       fieldsize = 0;
5244 
5245       /* If this is an array with an unspecified upper bound,
5246 	 the initializer determines the size.  */
5247       /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
5248 	 but we cannot do this until the deprecated support for
5249 	 initializing zero-length array members is removed.  */
5250       if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
5251 	  && (!TYPE_DOMAIN (TREE_TYPE (local->field))
5252 	      || !TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field)))))
5253 	{
5254 	  fieldsize = array_size_for_constructor (local->val);
5255 	  /* Given a non-empty initialization, this field had better
5256 	     be last.  Given a flexible array member, the next field
5257 	     on the chain is a TYPE_DECL of the enclosing struct.  */
5258 	  const_tree next = DECL_CHAIN (local->field);
5259 	  gcc_assert (!fieldsize || !next || TREE_CODE (next) != FIELD_DECL);
5260 	  tree size = TYPE_SIZE_UNIT (TREE_TYPE (local->val));
5261 	  gcc_checking_assert (compare_tree_int (size, fieldsize) == 0);
5262 	}
5263       else
5264 	fieldsize = tree_to_uhwi (DECL_SIZE_UNIT (local->field));
5265     }
5266   else
5267     fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
5268 
5269   /* Output the element's initial value.  */
5270   if (local->val == NULL_TREE)
5271     assemble_zeros (fieldsize);
5272   else
5273     fieldsize = output_constant (local->val, fieldsize, align2,
5274 				 local->reverse, false);
5275 
5276   /* Count its size.  */
5277   local->total_bytes += fieldsize;
5278 }
5279 
5280 /* Helper for output_constructor.  From the LOCAL state, output an element
5281    that is a true bitfield or part of an outer one.  BIT_OFFSET is the offset
5282    from the start of a possibly ongoing outer byte buffer.  */
5283 
5284 static void
output_constructor_bitfield(oc_local_state * local,unsigned int bit_offset)5285 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
5286 {
5287   /* Bit size of this element.  */
5288   HOST_WIDE_INT ebitsize
5289     = (local->field
5290        ? tree_to_uhwi (DECL_SIZE (local->field))
5291        : tree_to_uhwi (TYPE_SIZE (TREE_TYPE (local->type))));
5292 
5293   /* Relative index of this element if this is an array component.  */
5294   HOST_WIDE_INT relative_index
5295     = (!local->field
5296        ? (local->index
5297 	  ? (tree_to_shwi (local->index)
5298 	     - tree_to_shwi (local->min_index))
5299 	  : local->last_relative_index + 1)
5300        : 0);
5301 
5302   /* Bit position of this element from the start of the containing
5303      constructor.  */
5304   HOST_WIDE_INT constructor_relative_ebitpos
5305       = (local->field
5306 	 ? int_bit_position (local->field)
5307 	 : ebitsize * relative_index);
5308 
5309   /* Bit position of this element from the start of a possibly ongoing
5310      outer byte buffer.  */
5311   HOST_WIDE_INT byte_relative_ebitpos
5312     = bit_offset + constructor_relative_ebitpos;
5313 
5314   /* From the start of a possibly ongoing outer byte buffer, offsets to
5315      the first bit of this element and to the first bit past the end of
5316      this element.  */
5317   HOST_WIDE_INT next_offset = byte_relative_ebitpos;
5318   HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
5319 
5320   local->last_relative_index = relative_index;
5321 
5322   if (local->val == NULL_TREE)
5323     local->val = integer_zero_node;
5324 
5325   while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
5326 	 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
5327     local->val = TREE_OPERAND (local->val, 0);
5328 
5329   if (TREE_CODE (local->val) != INTEGER_CST
5330       && TREE_CODE (local->val) != CONSTRUCTOR)
5331     {
5332       error ("invalid initial value for member %qE", DECL_NAME (local->field));
5333       return;
5334     }
5335 
5336   /* If this field does not start in this (or next) byte, skip some bytes.  */
5337   if (next_offset / BITS_PER_UNIT != local->total_bytes)
5338     {
5339       /* Output remnant of any bit field in previous bytes.  */
5340       if (local->byte_buffer_in_use)
5341 	{
5342 	  assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5343 	  local->total_bytes++;
5344 	  local->byte_buffer_in_use = false;
5345 	}
5346 
5347       /* If still not at proper byte, advance to there.  */
5348       if (next_offset / BITS_PER_UNIT != local->total_bytes)
5349 	{
5350 	  gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
5351 	  assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
5352 	  local->total_bytes = next_offset / BITS_PER_UNIT;
5353 	}
5354     }
5355 
5356   /* Set up the buffer if necessary.  */
5357   if (!local->byte_buffer_in_use)
5358     {
5359       local->byte = 0;
5360       if (ebitsize > 0)
5361 	local->byte_buffer_in_use = true;
5362     }
5363 
5364   /* If this is nested constructor, recurse passing the bit offset and the
5365      pending data, then retrieve the new pending data afterwards.  */
5366   if (TREE_CODE (local->val) == CONSTRUCTOR)
5367     {
5368       oc_outer_state temp_state;
5369       temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5370       temp_state.byte = local->byte;
5371       local->total_bytes
5372 	+= output_constructor (local->val, 0, 0, local->reverse, &temp_state);
5373       local->byte = temp_state.byte;
5374       return;
5375     }
5376 
5377   /* Otherwise, we must split the element into pieces that fall within
5378      separate bytes, and combine each byte with previous or following
5379      bit-fields.  */
5380   while (next_offset < end_offset)
5381     {
5382       int this_time;
5383       int shift;
5384       unsigned HOST_WIDE_INT value;
5385       HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5386       HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5387 
5388       /* Advance from byte to byte within this element when necessary.  */
5389       while (next_byte != local->total_bytes)
5390 	{
5391 	  assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5392 	  local->total_bytes++;
5393 	  local->byte = 0;
5394 	}
5395 
5396       /* Number of bits we can process at once (all part of the same byte).  */
5397       this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5398       if (local->reverse ? !BYTES_BIG_ENDIAN : BYTES_BIG_ENDIAN)
5399 	{
5400 	  /* For big-endian data, take the most significant bits (of the
5401 	     bits that are significant) first and put them into bytes from
5402 	     the most significant end.  */
5403 	  shift = end_offset - next_offset - this_time;
5404 
5405 	  /* Don't try to take a bunch of bits that cross
5406 	     the word boundary in the INTEGER_CST.  We can
5407 	     only select bits from one element.  */
5408 	  if ((shift / HOST_BITS_PER_WIDE_INT)
5409 	      != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5410 	    {
5411 	      const int end = shift + this_time - 1;
5412 	      shift = end & -HOST_BITS_PER_WIDE_INT;
5413 	      this_time = end - shift + 1;
5414 	    }
5415 
5416 	  /* Now get the bits we want to insert.  */
5417 	  value = wi::extract_uhwi (wi::to_widest (local->val),
5418 				    shift, this_time);
5419 
5420 	  /* Get the result.  This works only when:
5421 	     1 <= this_time <= HOST_BITS_PER_WIDE_INT.  */
5422 	  local->byte |= value << (BITS_PER_UNIT - this_time - next_bit);
5423 	}
5424       else
5425 	{
5426 	  /* On little-endian machines, take the least significant bits of
5427 	     the value first and pack them starting at the least significant
5428 	     bits of the bytes.  */
5429 	  shift = next_offset - byte_relative_ebitpos;
5430 
5431 	  /* Don't try to take a bunch of bits that cross
5432 	     the word boundary in the INTEGER_CST.  We can
5433 	     only select bits from one element.  */
5434 	  if ((shift / HOST_BITS_PER_WIDE_INT)
5435 	      != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5436 	    this_time
5437 	      = HOST_BITS_PER_WIDE_INT - (shift & (HOST_BITS_PER_WIDE_INT - 1));
5438 
5439 	  /* Now get the bits we want to insert.  */
5440 	  value = wi::extract_uhwi (wi::to_widest (local->val),
5441 				    shift, this_time);
5442 
5443 	  /* Get the result.  This works only when:
5444 	     1 <= this_time <= HOST_BITS_PER_WIDE_INT.  */
5445 	  local->byte |= value << next_bit;
5446 	}
5447 
5448       next_offset += this_time;
5449       local->byte_buffer_in_use = true;
5450     }
5451 }
5452 
5453 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5454    Generate at least SIZE bytes, padding if necessary.  OUTER designates the
5455    caller output state of relevance in recursive invocations.  */
5456 
5457 static unsigned HOST_WIDE_INT
output_constructor(tree exp,unsigned HOST_WIDE_INT size,unsigned int align,bool reverse,oc_outer_state * outer)5458 output_constructor (tree exp, unsigned HOST_WIDE_INT size, unsigned int align,
5459 		    bool reverse, oc_outer_state *outer)
5460 {
5461   unsigned HOST_WIDE_INT cnt;
5462   constructor_elt *ce;
5463   oc_local_state local;
5464 
5465   /* Setup our local state to communicate with helpers.  */
5466   local.exp = exp;
5467   local.type = TREE_TYPE (exp);
5468   local.size = size;
5469   local.align = align;
5470   if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5471     local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5472   else
5473     local.min_index = integer_zero_node;
5474 
5475   local.total_bytes = 0;
5476   local.byte_buffer_in_use = outer != NULL;
5477   local.byte = outer ? outer->byte : 0;
5478   local.last_relative_index = -1;
5479   /* The storage order is specified for every aggregate type.  */
5480   if (AGGREGATE_TYPE_P (local.type))
5481     local.reverse = TYPE_REVERSE_STORAGE_ORDER (local.type);
5482   else
5483     local.reverse = reverse;
5484 
5485   gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5486 
5487   /* As CE goes through the elements of the constant, FIELD goes through the
5488      structure fields if the constant is a structure.  If the constant is a
5489      union, we override this by getting the field from the TREE_LIST element.
5490      But the constant could also be an array.  Then FIELD is zero.
5491 
5492      There is always a maximum of one element in the chain LINK for unions
5493      (even if the initializer in a source program incorrectly contains
5494      more one).  */
5495 
5496   if (TREE_CODE (local.type) == RECORD_TYPE)
5497     local.field = TYPE_FIELDS (local.type);
5498   else
5499     local.field = NULL_TREE;
5500 
5501   for (cnt = 0;
5502        vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5503        cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5504     {
5505       local.val = ce->value;
5506       local.index = NULL_TREE;
5507 
5508       /* The element in a union constructor specifies the proper field
5509 	 or index.  */
5510       if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5511 	local.field = ce->index;
5512 
5513       else if (TREE_CODE (local.type) == ARRAY_TYPE)
5514 	local.index = ce->index;
5515 
5516       if (local.field && flag_verbose_asm)
5517 	fprintf (asm_out_file, "%s %s:\n",
5518 		 ASM_COMMENT_START,
5519 		 DECL_NAME (local.field)
5520 		 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5521 		 : "<anonymous>");
5522 
5523       /* Eliminate the marker that makes a cast not be an lvalue.  */
5524       if (local.val != NULL_TREE)
5525 	STRIP_NOPS (local.val);
5526 
5527       /* Output the current element, using the appropriate helper ...  */
5528 
5529       /* For an array slice not part of an outer bitfield.  */
5530       if (!outer
5531 	  && local.index != NULL_TREE
5532 	  && TREE_CODE (local.index) == RANGE_EXPR)
5533 	output_constructor_array_range (&local);
5534 
5535       /* For a field that is neither a true bitfield nor part of an outer one,
5536 	 known to be at least byte aligned and multiple-of-bytes long.  */
5537       else if (!outer
5538 	       && (local.field == NULL_TREE
5539 		   || !CONSTRUCTOR_BITFIELD_P (local.field)))
5540 	output_constructor_regular_field (&local);
5541 
5542       /* For a true bitfield or part of an outer one.  Only INTEGER_CSTs are
5543 	 supported for scalar fields, so we may need to convert first.  */
5544       else
5545         {
5546 	  if (TREE_CODE (local.val) == REAL_CST)
5547 	    local.val
5548 	      = fold_unary (VIEW_CONVERT_EXPR,
5549 			    build_nonstandard_integer_type
5550 			    (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5551 			    local.val);
5552 	  output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5553 	}
5554     }
5555 
5556   /* If we are not at toplevel, save the pending data for our caller.
5557      Otherwise output the pending data and padding zeros as needed. */
5558   if (outer)
5559     outer->byte = local.byte;
5560   else
5561     {
5562       if (local.byte_buffer_in_use)
5563 	{
5564 	  assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5565 	  local.total_bytes++;
5566 	}
5567 
5568       if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5569 	{
5570 	  assemble_zeros (local.size - local.total_bytes);
5571 	  local.total_bytes = local.size;
5572 	}
5573     }
5574 
5575   return local.total_bytes;
5576 }
5577 
5578 /* Mark DECL as weak.  */
5579 
5580 static void
mark_weak(tree decl)5581 mark_weak (tree decl)
5582 {
5583   if (DECL_WEAK (decl))
5584     return;
5585 
5586   struct symtab_node *n = symtab_node::get (decl);
5587   if (n && n->refuse_visibility_changes)
5588     error ("%+qD declared weak after being used", decl);
5589   DECL_WEAK (decl) = 1;
5590 
5591   if (DECL_RTL_SET_P (decl)
5592       && MEM_P (DECL_RTL (decl))
5593       && XEXP (DECL_RTL (decl), 0)
5594       && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5595     SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5596 }
5597 
5598 /* Merge weak status between NEWDECL and OLDDECL.  */
5599 
5600 void
merge_weak(tree newdecl,tree olddecl)5601 merge_weak (tree newdecl, tree olddecl)
5602 {
5603   if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5604     {
5605       if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5606         {
5607           tree *pwd;
5608           /* We put the NEWDECL on the weak_decls list at some point
5609              and OLDDECL as well.  Keep just OLDDECL on the list.  */
5610 	  for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5611 	    if (TREE_VALUE (*pwd) == newdecl)
5612 	      {
5613 	        *pwd = TREE_CHAIN (*pwd);
5614 		break;
5615 	      }
5616         }
5617       return;
5618     }
5619 
5620   if (DECL_WEAK (newdecl))
5621     {
5622       tree wd;
5623 
5624       /* NEWDECL is weak, but OLDDECL is not.  */
5625 
5626       /* If we already output the OLDDECL, we're in trouble; we can't
5627 	 go back and make it weak.  This should never happen in
5628 	 unit-at-a-time compilation.  */
5629       gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5630 
5631       /* If we've already generated rtl referencing OLDDECL, we may
5632 	 have done so in a way that will not function properly with
5633 	 a weak symbol.  Again in unit-at-a-time this should be
5634 	 impossible.  */
5635       gcc_assert (!TREE_USED (olddecl)
5636 	          || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5637 
5638       /* PR 49899: You cannot convert a static function into a weak, public function.  */
5639       if (! TREE_PUBLIC (olddecl) && TREE_PUBLIC (newdecl))
5640 	error ("weak declaration of %q+D being applied to a already "
5641 	       "existing, static definition", newdecl);
5642 
5643       if (TARGET_SUPPORTS_WEAK)
5644 	{
5645 	  /* We put the NEWDECL on the weak_decls list at some point.
5646 	     Replace it with the OLDDECL.  */
5647 	  for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5648 	    if (TREE_VALUE (wd) == newdecl)
5649 	      {
5650 		TREE_VALUE (wd) = olddecl;
5651 		break;
5652 	      }
5653 	  /* We may not find the entry on the list.  If NEWDECL is a
5654 	     weak alias, then we will have already called
5655 	     globalize_decl to remove the entry; in that case, we do
5656 	     not need to do anything.  */
5657 	}
5658 
5659       /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping.  */
5660       mark_weak (olddecl);
5661     }
5662   else
5663     /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5664        weak.  Just update NEWDECL to indicate that it's weak too.  */
5665     mark_weak (newdecl);
5666 }
5667 
5668 /* Declare DECL to be a weak symbol.  */
5669 
5670 void
declare_weak(tree decl)5671 declare_weak (tree decl)
5672 {
5673   /* With -fsyntax-only, TREE_ASM_WRITTEN might be set on certain function
5674      decls earlier than normally, but as with -fsyntax-only nothing is really
5675      emitted, there is no harm in marking it weak later.  */
5676   gcc_assert (TREE_CODE (decl) != FUNCTION_DECL
5677 	      || !TREE_ASM_WRITTEN (decl)
5678 	      || flag_syntax_only);
5679   if (! TREE_PUBLIC (decl))
5680     {
5681       error ("weak declaration of %q+D must be public", decl);
5682       return;
5683     }
5684   else if (!TARGET_SUPPORTS_WEAK)
5685     warning (0, "weak declaration of %q+D not supported", decl);
5686 
5687   mark_weak (decl);
5688   if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5689     DECL_ATTRIBUTES (decl)
5690       = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5691 }
5692 
5693 static void
weak_finish_1(tree decl)5694 weak_finish_1 (tree decl)
5695 {
5696 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5697   const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5698 #endif
5699 
5700   if (! TREE_USED (decl))
5701     return;
5702 
5703 #ifdef ASM_WEAKEN_DECL
5704   ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5705 #else
5706 #ifdef ASM_WEAKEN_LABEL
5707   ASM_WEAKEN_LABEL (asm_out_file, name);
5708 #else
5709 #ifdef ASM_OUTPUT_WEAK_ALIAS
5710   {
5711     static bool warn_once = 0;
5712     if (! warn_once)
5713       {
5714 	warning (0, "only weak aliases are supported in this configuration");
5715 	warn_once = 1;
5716       }
5717     return;
5718   }
5719 #endif
5720 #endif
5721 #endif
5722 }
5723 
5724 /* Fiven an assembly name, find the decl it is associated with.  */
5725 static tree
find_decl(tree target)5726 find_decl (tree target)
5727 {
5728   symtab_node *node = symtab_node::get_for_asmname (target);
5729   if (node)
5730     return node->decl;
5731   return NULL_TREE;
5732 }
5733 
5734 /* This TREE_LIST contains weakref targets.  */
5735 
5736 static GTY(()) tree weakref_targets;
5737 
5738 /* Emit any pending weak declarations.  */
5739 
5740 void
weak_finish(void)5741 weak_finish (void)
5742 {
5743   tree t;
5744 
5745   for (t = weakref_targets; t; t = TREE_CHAIN (t))
5746     {
5747       tree alias_decl = TREE_PURPOSE (t);
5748       tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5749 
5750       if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl))
5751          || TREE_SYMBOL_REFERENCED (target))
5752 	/* Remove alias_decl from the weak list, but leave entries for
5753 	   the target alone.  */
5754 	target = NULL_TREE;
5755 #ifndef ASM_OUTPUT_WEAKREF
5756       else if (! TREE_SYMBOL_REFERENCED (target))
5757 	{
5758 	  /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5759 	     defined, otherwise we and weak_finish_1 would use
5760 	     different macros.  */
5761 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5762 	  ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5763 # else
5764 	  tree decl = find_decl (target);
5765 
5766 	  if (! decl)
5767 	    {
5768 	      decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5769 				 TREE_CODE (alias_decl), target,
5770 				 TREE_TYPE (alias_decl));
5771 
5772 	      DECL_EXTERNAL (decl) = 1;
5773 	      TREE_PUBLIC (decl) = 1;
5774 	      DECL_ARTIFICIAL (decl) = 1;
5775 	      TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5776 	      TREE_USED (decl) = 1;
5777 	    }
5778 
5779 	  weak_finish_1 (decl);
5780 # endif
5781 	}
5782 #endif
5783 
5784       {
5785 	tree *p;
5786 	tree t2;
5787 
5788 	/* Remove the alias and the target from the pending weak list
5789 	   so that we do not emit any .weak directives for the former,
5790 	   nor multiple .weak directives for the latter.  */
5791 	for (p = &weak_decls; (t2 = *p) ; )
5792 	  {
5793 	    if (TREE_VALUE (t2) == alias_decl
5794 		|| target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5795 	      *p = TREE_CHAIN (t2);
5796 	    else
5797 	      p = &TREE_CHAIN (t2);
5798 	  }
5799 
5800 	/* Remove other weakrefs to the same target, to speed things up.  */
5801 	for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5802 	  {
5803 	    if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5804 	      *p = TREE_CHAIN (t2);
5805 	    else
5806 	      p = &TREE_CHAIN (t2);
5807 	  }
5808       }
5809     }
5810 
5811   for (t = weak_decls; t; t = TREE_CHAIN (t))
5812     {
5813       tree decl = TREE_VALUE (t);
5814 
5815       weak_finish_1 (decl);
5816     }
5817 }
5818 
5819 /* Emit the assembly bits to indicate that DECL is globally visible.  */
5820 
5821 static void
globalize_decl(tree decl)5822 globalize_decl (tree decl)
5823 {
5824 
5825 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5826   if (DECL_WEAK (decl))
5827     {
5828       const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5829       tree *p, t;
5830 
5831 #ifdef ASM_WEAKEN_DECL
5832       ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5833 #else
5834       ASM_WEAKEN_LABEL (asm_out_file, name);
5835 #endif
5836 
5837       /* Remove this function from the pending weak list so that
5838 	 we do not emit multiple .weak directives for it.  */
5839       for (p = &weak_decls; (t = *p) ; )
5840 	{
5841 	  if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5842 	    *p = TREE_CHAIN (t);
5843 	  else
5844 	    p = &TREE_CHAIN (t);
5845 	}
5846 
5847       /* Remove weakrefs to the same target from the pending weakref
5848 	 list, for the same reason.  */
5849       for (p = &weakref_targets; (t = *p) ; )
5850 	{
5851 	  if (DECL_ASSEMBLER_NAME (decl)
5852 	      == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5853 	    *p = TREE_CHAIN (t);
5854 	  else
5855 	    p = &TREE_CHAIN (t);
5856 	}
5857 
5858       return;
5859     }
5860 #endif
5861 
5862   targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5863 }
5864 
5865 vec<alias_pair, va_gc> *alias_pairs;
5866 
5867 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5868    or ASM_OUTPUT_DEF_FROM_DECLS.  The function defines the symbol whose
5869    tree node is DECL to have the value of the tree node TARGET.  */
5870 
5871 void
do_assemble_alias(tree decl,tree target)5872 do_assemble_alias (tree decl, tree target)
5873 {
5874   tree id;
5875 
5876   /* Emulated TLS had better not get this var.  */
5877   gcc_assert (!(!targetm.have_tls
5878 		&& VAR_P (decl)
5879 		&& DECL_THREAD_LOCAL_P (decl)));
5880 
5881   if (TREE_ASM_WRITTEN (decl))
5882     return;
5883 
5884   id = DECL_ASSEMBLER_NAME (decl);
5885   ultimate_transparent_alias_target (&id);
5886   ultimate_transparent_alias_target (&target);
5887 
5888   /* We must force creation of DECL_RTL for debug info generation, even though
5889      we don't use it here.  */
5890   make_decl_rtl (decl);
5891 
5892   TREE_ASM_WRITTEN (decl) = 1;
5893   TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5894   TREE_ASM_WRITTEN (id) = 1;
5895 
5896   if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5897     {
5898       if (!TREE_SYMBOL_REFERENCED (target))
5899 	weakref_targets = tree_cons (decl, target, weakref_targets);
5900 
5901 #ifdef ASM_OUTPUT_WEAKREF
5902       ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5903 			  IDENTIFIER_POINTER (id),
5904 			  IDENTIFIER_POINTER (target));
5905 #else
5906       if (!TARGET_SUPPORTS_WEAK)
5907 	{
5908 	  error_at (DECL_SOURCE_LOCATION (decl),
5909 		    "weakref is not supported in this configuration");
5910 	  return;
5911 	}
5912 #endif
5913       return;
5914     }
5915 
5916 #ifdef ASM_OUTPUT_DEF
5917   tree orig_decl = decl;
5918 
5919   /* Make name accessible from other files, if appropriate.  */
5920 
5921   if (TREE_PUBLIC (decl) || TREE_PUBLIC (orig_decl))
5922     {
5923       globalize_decl (decl);
5924       maybe_assemble_visibility (decl);
5925     }
5926   if (TREE_CODE (decl) == FUNCTION_DECL
5927       && cgraph_node::get (decl)->ifunc_resolver)
5928     {
5929 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5930       if (targetm.has_ifunc_p ())
5931 	ASM_OUTPUT_TYPE_DIRECTIVE
5932 	  (asm_out_file, IDENTIFIER_POINTER (id),
5933 	   IFUNC_ASM_TYPE);
5934       else
5935 #endif
5936 	error_at (DECL_SOURCE_LOCATION (decl),
5937 		  "ifunc is not supported on this target");
5938     }
5939 
5940 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5941   ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5942 # else
5943   ASM_OUTPUT_DEF (asm_out_file,
5944 		  IDENTIFIER_POINTER (id),
5945 		  IDENTIFIER_POINTER (target));
5946 # endif
5947 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5948   {
5949     const char *name;
5950     tree *p, t;
5951 
5952     name = IDENTIFIER_POINTER (id);
5953 # ifdef ASM_WEAKEN_DECL
5954     ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5955 # else
5956     ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5957 # endif
5958     /* Remove this function from the pending weak list so that
5959        we do not emit multiple .weak directives for it.  */
5960     for (p = &weak_decls; (t = *p) ; )
5961       if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t))
5962 	  || id == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5963 	*p = TREE_CHAIN (t);
5964       else
5965 	p = &TREE_CHAIN (t);
5966 
5967     /* Remove weakrefs to the same target from the pending weakref
5968        list, for the same reason.  */
5969     for (p = &weakref_targets; (t = *p) ; )
5970       {
5971 	if (id == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5972 	  *p = TREE_CHAIN (t);
5973 	else
5974 	  p = &TREE_CHAIN (t);
5975       }
5976   }
5977 #endif
5978 }
5979 
5980 /* Emit an assembler directive to make the symbol for DECL an alias to
5981    the symbol for TARGET.  */
5982 
5983 void
assemble_alias(tree decl,tree target)5984 assemble_alias (tree decl, tree target)
5985 {
5986   tree target_decl;
5987 
5988   if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5989     {
5990       tree alias = DECL_ASSEMBLER_NAME (decl);
5991 
5992       ultimate_transparent_alias_target (&target);
5993 
5994       if (alias == target)
5995 	error ("weakref %q+D ultimately targets itself", decl);
5996       if (TREE_PUBLIC (decl))
5997 	error ("weakref %q+D must have static linkage", decl);
5998     }
5999   else
6000     {
6001 #if !defined (ASM_OUTPUT_DEF)
6002 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
6003       error_at (DECL_SOURCE_LOCATION (decl),
6004 		"alias definitions not supported in this configuration");
6005       TREE_ASM_WRITTEN (decl) = 1;
6006       return;
6007 # else
6008       if (!DECL_WEAK (decl))
6009 	{
6010 	  /* NB: ifunc_resolver isn't set when an error is detected.  */
6011 	  if (TREE_CODE (decl) == FUNCTION_DECL
6012 	      && lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
6013 	    error_at (DECL_SOURCE_LOCATION (decl),
6014 		      "ifunc is not supported in this configuration");
6015 	  else
6016 	    error_at (DECL_SOURCE_LOCATION (decl),
6017 		      "only weak aliases are supported in this configuration");
6018 	  TREE_ASM_WRITTEN (decl) = 1;
6019 	  return;
6020 	}
6021 # endif
6022 #endif
6023     }
6024   TREE_USED (decl) = 1;
6025 
6026   /* Allow aliases to aliases.  */
6027   if (TREE_CODE (decl) == FUNCTION_DECL)
6028     cgraph_node::get_create (decl)->alias = true;
6029   else
6030     varpool_node::get_create (decl)->alias = true;
6031 
6032   /* If the target has already been emitted, we don't have to queue the
6033      alias.  This saves a tad of memory.  */
6034   if (symtab->global_info_ready)
6035     target_decl = find_decl (target);
6036   else
6037     target_decl= NULL;
6038   if ((target_decl && TREE_ASM_WRITTEN (target_decl))
6039       || symtab->state >= EXPANSION)
6040     do_assemble_alias (decl, target);
6041   else
6042     {
6043       alias_pair p = {decl, target};
6044       vec_safe_push (alias_pairs, p);
6045     }
6046 }
6047 
6048 /* Record and output a table of translations from original function
6049    to its transaction aware clone.  Note that tm_pure functions are
6050    considered to be their own clone.  */
6051 
6052 struct tm_clone_hasher : ggc_cache_ptr_hash<tree_map>
6053 {
hashtm_clone_hasher6054   static hashval_t hash (tree_map *m) { return tree_map_hash (m); }
equaltm_clone_hasher6055   static bool equal (tree_map *a, tree_map *b) { return tree_map_eq (a, b); }
6056 
6057   static int
keep_cache_entrytm_clone_hasher6058   keep_cache_entry (tree_map *&e)
6059   {
6060     return ggc_marked_p (e->base.from);
6061   }
6062 };
6063 
6064 static GTY((cache)) hash_table<tm_clone_hasher> *tm_clone_hash;
6065 
6066 void
record_tm_clone_pair(tree o,tree n)6067 record_tm_clone_pair (tree o, tree n)
6068 {
6069   struct tree_map **slot, *h;
6070 
6071   if (tm_clone_hash == NULL)
6072     tm_clone_hash = hash_table<tm_clone_hasher>::create_ggc (32);
6073 
6074   h = ggc_alloc<tree_map> ();
6075   h->hash = htab_hash_pointer (o);
6076   h->base.from = o;
6077   h->to = n;
6078 
6079   slot = tm_clone_hash->find_slot_with_hash (h, h->hash, INSERT);
6080   *slot = h;
6081 }
6082 
6083 tree
get_tm_clone_pair(tree o)6084 get_tm_clone_pair (tree o)
6085 {
6086   if (tm_clone_hash)
6087     {
6088       struct tree_map *h, in;
6089 
6090       in.base.from = o;
6091       in.hash = htab_hash_pointer (o);
6092       h = tm_clone_hash->find_with_hash (&in, in.hash);
6093       if (h)
6094 	return h->to;
6095     }
6096   return NULL_TREE;
6097 }
6098 
6099 struct tm_alias_pair
6100 {
6101   unsigned int uid;
6102   tree from;
6103   tree to;
6104 };
6105 
6106 
6107 /* Dump the actual pairs to the .tm_clone_table section.  */
6108 
6109 static void
dump_tm_clone_pairs(vec<tm_alias_pair> tm_alias_pairs)6110 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
6111 {
6112   unsigned i;
6113   tm_alias_pair *p;
6114   bool switched = false;
6115 
6116   FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
6117     {
6118       tree src = p->from;
6119       tree dst = p->to;
6120       struct cgraph_node *src_n = cgraph_node::get (src);
6121       struct cgraph_node *dst_n = cgraph_node::get (dst);
6122 
6123       /* The function ipa_tm_create_version() marks the clone as needed if
6124 	 the original function was needed.  But we also mark the clone as
6125 	 needed if we ever called the clone indirectly through
6126 	 TM_GETTMCLONE.  If neither of these are true, we didn't generate
6127 	 a clone, and we didn't call it indirectly... no sense keeping it
6128 	 in the clone table.  */
6129       if (!dst_n || !dst_n->definition)
6130 	continue;
6131 
6132       /* This covers the case where we have optimized the original
6133 	 function away, and only access the transactional clone.  */
6134       if (!src_n || !src_n->definition)
6135 	continue;
6136 
6137       if (!switched)
6138 	{
6139 	  switch_to_section (targetm.asm_out.tm_clone_table_section ());
6140 	  assemble_align (POINTER_SIZE);
6141 	  switched = true;
6142 	}
6143 
6144       assemble_integer (XEXP (DECL_RTL (src), 0),
6145 			POINTER_SIZE_UNITS, POINTER_SIZE, 1);
6146       assemble_integer (XEXP (DECL_RTL (dst), 0),
6147 			POINTER_SIZE_UNITS, POINTER_SIZE, 1);
6148     }
6149 }
6150 
6151 /* Provide a default for the tm_clone_table section.  */
6152 
6153 section *
default_clone_table_section(void)6154 default_clone_table_section (void)
6155 {
6156   return get_named_section (NULL, ".tm_clone_table", 3);
6157 }
6158 
6159 /* Helper comparison function for qsorting by the DECL_UID stored in
6160    alias_pair->emitted_diags.  */
6161 
6162 static int
tm_alias_pair_cmp(const void * x,const void * y)6163 tm_alias_pair_cmp (const void *x, const void *y)
6164 {
6165   const tm_alias_pair *p1 = (const tm_alias_pair *) x;
6166   const tm_alias_pair *p2 = (const tm_alias_pair *) y;
6167   if (p1->uid < p2->uid)
6168     return -1;
6169   if (p1->uid > p2->uid)
6170     return 1;
6171   return 0;
6172 }
6173 
6174 void
finish_tm_clone_pairs(void)6175 finish_tm_clone_pairs (void)
6176 {
6177   vec<tm_alias_pair> tm_alias_pairs = vNULL;
6178 
6179   if (tm_clone_hash == NULL)
6180     return;
6181 
6182   /* We need a determenistic order for the .tm_clone_table, otherwise
6183      we will get bootstrap comparison failures, so dump the hash table
6184      to a vector, sort it, and dump the vector.  */
6185 
6186   /* Dump the hashtable to a vector.  */
6187   tree_map *map;
6188   hash_table<tm_clone_hasher>::iterator iter;
6189   FOR_EACH_HASH_TABLE_ELEMENT (*tm_clone_hash, map, tree_map *, iter)
6190     {
6191       tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
6192       tm_alias_pairs.safe_push (p);
6193     }
6194   /* Sort it.  */
6195   tm_alias_pairs.qsort (tm_alias_pair_cmp);
6196 
6197   /* Dump it.  */
6198   dump_tm_clone_pairs (tm_alias_pairs);
6199 
6200   tm_clone_hash->empty ();
6201   tm_clone_hash = NULL;
6202   tm_alias_pairs.release ();
6203 }
6204 
6205 
6206 /* Emit an assembler directive to set symbol for DECL visibility to
6207    the visibility type VIS, which must not be VISIBILITY_DEFAULT.  */
6208 
6209 void
default_assemble_visibility(tree decl ATTRIBUTE_UNUSED,int vis ATTRIBUTE_UNUSED)6210 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
6211 			     int vis ATTRIBUTE_UNUSED)
6212 {
6213 #ifdef HAVE_GAS_HIDDEN
6214   static const char * const visibility_types[] = {
6215     NULL, "protected", "hidden", "internal"
6216   };
6217 
6218   const char *name, *type;
6219   tree id;
6220 
6221   id = DECL_ASSEMBLER_NAME (decl);
6222   ultimate_transparent_alias_target (&id);
6223   name = IDENTIFIER_POINTER (id);
6224 
6225   type = visibility_types[vis];
6226 
6227   fprintf (asm_out_file, "\t.%s\t", type);
6228   assemble_name (asm_out_file, name);
6229   fprintf (asm_out_file, "\n");
6230 #else
6231   if (!DECL_ARTIFICIAL (decl))
6232     warning (OPT_Wattributes, "visibility attribute not supported "
6233 	     "in this configuration; ignored");
6234 #endif
6235 }
6236 
6237 /* A helper function to call assemble_visibility when needed for a decl.  */
6238 
6239 int
maybe_assemble_visibility(tree decl)6240 maybe_assemble_visibility (tree decl)
6241 {
6242   enum symbol_visibility vis = DECL_VISIBILITY (decl);
6243   if (vis != VISIBILITY_DEFAULT)
6244     {
6245       targetm.asm_out.assemble_visibility (decl, vis);
6246       return 1;
6247     }
6248   else
6249     return 0;
6250 }
6251 
6252 /* Returns 1 if the target configuration supports defining public symbols
6253    so that one of them will be chosen at link time instead of generating a
6254    multiply-defined symbol error, whether through the use of weak symbols or
6255    a target-specific mechanism for having duplicates discarded.  */
6256 
6257 int
supports_one_only(void)6258 supports_one_only (void)
6259 {
6260   if (SUPPORTS_ONE_ONLY)
6261     return 1;
6262   return TARGET_SUPPORTS_WEAK;
6263 }
6264 
6265 /* Set up DECL as a public symbol that can be defined in multiple
6266    translation units without generating a linker error.  */
6267 
6268 void
make_decl_one_only(tree decl,tree comdat_group)6269 make_decl_one_only (tree decl, tree comdat_group)
6270 {
6271   struct symtab_node *symbol;
6272   gcc_assert (VAR_OR_FUNCTION_DECL_P (decl));
6273 
6274   TREE_PUBLIC (decl) = 1;
6275 
6276   if (VAR_P (decl))
6277     symbol = varpool_node::get_create (decl);
6278   else
6279     symbol = cgraph_node::get_create (decl);
6280 
6281   if (SUPPORTS_ONE_ONLY)
6282     {
6283 #ifdef MAKE_DECL_ONE_ONLY
6284       MAKE_DECL_ONE_ONLY (decl);
6285 #endif
6286       symbol->set_comdat_group (comdat_group);
6287     }
6288   else if (VAR_P (decl)
6289            && (DECL_INITIAL (decl) == 0
6290 	       || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
6291     DECL_COMMON (decl) = 1;
6292   else
6293     {
6294       gcc_assert (TARGET_SUPPORTS_WEAK);
6295       DECL_WEAK (decl) = 1;
6296     }
6297 }
6298 
6299 void
init_varasm_once(void)6300 init_varasm_once (void)
6301 {
6302   section_htab = hash_table<section_hasher>::create_ggc (31);
6303   object_block_htab = hash_table<object_block_hasher>::create_ggc (31);
6304   const_desc_htab = hash_table<tree_descriptor_hasher>::create_ggc (1009);
6305 
6306   shared_constant_pool = create_constant_pool ();
6307 
6308 #ifdef TEXT_SECTION_ASM_OP
6309   text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
6310 				      TEXT_SECTION_ASM_OP);
6311 #endif
6312 
6313 #ifdef DATA_SECTION_ASM_OP
6314   data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
6315 				      DATA_SECTION_ASM_OP);
6316 #endif
6317 
6318 #ifdef SDATA_SECTION_ASM_OP
6319   sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
6320 				       SDATA_SECTION_ASM_OP);
6321 #endif
6322 
6323 #ifdef READONLY_DATA_SECTION_ASM_OP
6324   readonly_data_section = get_unnamed_section (0, output_section_asm_op,
6325 					       READONLY_DATA_SECTION_ASM_OP);
6326 #endif
6327 
6328 #ifdef CTORS_SECTION_ASM_OP
6329   ctors_section = get_unnamed_section (0, output_section_asm_op,
6330 				       CTORS_SECTION_ASM_OP);
6331 #endif
6332 
6333 #ifdef DTORS_SECTION_ASM_OP
6334   dtors_section = get_unnamed_section (0, output_section_asm_op,
6335 				       DTORS_SECTION_ASM_OP);
6336 #endif
6337 
6338 #ifdef BSS_SECTION_ASM_OP
6339   bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6340 				     output_section_asm_op,
6341 				     BSS_SECTION_ASM_OP);
6342 #endif
6343 
6344 #ifdef SBSS_SECTION_ASM_OP
6345   sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6346 				      output_section_asm_op,
6347 				      SBSS_SECTION_ASM_OP);
6348 #endif
6349 
6350   tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6351 					   | SECTION_COMMON, emit_tls_common);
6352   lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6353 					| SECTION_COMMON, emit_local);
6354   comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6355 				       | SECTION_COMMON, emit_common);
6356 
6357 #if defined ASM_OUTPUT_ALIGNED_BSS
6358   bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
6359 					       emit_bss);
6360 #endif
6361 
6362   targetm.asm_out.init_sections ();
6363 
6364   if (readonly_data_section == NULL)
6365     readonly_data_section = text_section;
6366 
6367 #ifdef ASM_OUTPUT_EXTERNAL
6368   pending_assemble_externals_set = new hash_set<tree>;
6369 #endif
6370 }
6371 
6372 enum tls_model
decl_default_tls_model(const_tree decl)6373 decl_default_tls_model (const_tree decl)
6374 {
6375   enum tls_model kind;
6376   bool is_local;
6377 
6378   is_local = targetm.binds_local_p (decl);
6379   if (!flag_shlib)
6380     {
6381       if (is_local)
6382 	kind = TLS_MODEL_LOCAL_EXEC;
6383       else
6384 	kind = TLS_MODEL_INITIAL_EXEC;
6385     }
6386 
6387   /* Local dynamic is inefficient when we're not combining the
6388      parts of the address.  */
6389   else if (optimize && is_local)
6390     kind = TLS_MODEL_LOCAL_DYNAMIC;
6391   else
6392     kind = TLS_MODEL_GLOBAL_DYNAMIC;
6393   if (kind < flag_tls_default)
6394     kind = flag_tls_default;
6395 
6396   return kind;
6397 }
6398 
6399 /* Select a set of attributes for section NAME based on the properties
6400    of DECL and whether or not RELOC indicates that DECL's initializer
6401    might contain runtime relocations.
6402 
6403    We make the section read-only and executable for a function decl,
6404    read-only for a const data decl, and writable for a non-const data decl.  */
6405 
6406 unsigned int
default_section_type_flags(tree decl,const char * name,int reloc)6407 default_section_type_flags (tree decl, const char *name, int reloc)
6408 {
6409   unsigned int flags;
6410 
6411   if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6412     flags = SECTION_CODE;
6413   else if (decl)
6414     {
6415       enum section_category category
6416 	= categorize_decl_for_section (decl, reloc);
6417       if (decl_readonly_section_1 (category))
6418 	flags = 0;
6419       else if (category == SECCAT_DATA_REL_RO
6420 	       || category == SECCAT_DATA_REL_RO_LOCAL)
6421 	flags = SECTION_WRITE | SECTION_RELRO;
6422       else
6423 	flags = SECTION_WRITE;
6424     }
6425   else
6426     {
6427       flags = SECTION_WRITE;
6428       if (strcmp (name, ".data.rel.ro") == 0
6429 	  || strcmp (name, ".data.rel.ro.local") == 0)
6430 	flags |= SECTION_RELRO;
6431     }
6432 
6433   if (decl && DECL_P (decl) && DECL_COMDAT_GROUP (decl))
6434     flags |= SECTION_LINKONCE;
6435 
6436   if (strcmp (name, ".vtable_map_vars") == 0)
6437     flags |= SECTION_LINKONCE;
6438 
6439   if (decl && VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6440     flags |= SECTION_TLS | SECTION_WRITE;
6441 
6442   if (strcmp (name, ".bss") == 0
6443       || strncmp (name, ".bss.", 5) == 0
6444       || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6445       || strcmp (name, ".persistent.bss") == 0
6446       || strcmp (name, ".sbss") == 0
6447       || strncmp (name, ".sbss.", 6) == 0
6448       || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6449     flags |= SECTION_BSS;
6450 
6451   if (strcmp (name, ".tdata") == 0
6452       || strncmp (name, ".tdata.", 7) == 0
6453       || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6454     flags |= SECTION_TLS;
6455 
6456   if (strcmp (name, ".tbss") == 0
6457       || strncmp (name, ".tbss.", 6) == 0
6458       || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6459     flags |= SECTION_TLS | SECTION_BSS;
6460 
6461   /* Various sections have special ELF types that the assembler will
6462      assign by default based on the name.  They are neither SHT_PROGBITS
6463      nor SHT_NOBITS, so when changing sections we don't want to print a
6464      section type (@progbits or @nobits).  Rather than duplicating the
6465      assembler's knowledge of what those special name patterns are, just
6466      let the assembler choose the type if we don't know a specific
6467      reason to set it to something other than the default.  SHT_PROGBITS
6468      is the default for sections whose name is not specially known to
6469      the assembler, so it does no harm to leave the choice to the
6470      assembler when @progbits is the best thing we know to use.  If
6471      someone is silly enough to emit code or TLS variables to one of
6472      these sections, then don't handle them specially.
6473 
6474      default_elf_asm_named_section (below) handles the BSS, TLS, ENTSIZE, and
6475      LINKONCE cases when NOTYPE is not set, so leave those to its logic.  */
6476   if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS | SECTION_ENTSIZE))
6477       && !(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE)))
6478     flags |= SECTION_NOTYPE;
6479 
6480   return flags;
6481 }
6482 
6483 /* Return true if the target supports some form of global BSS,
6484    either through bss_noswitch_section, or by selecting a BSS
6485    section in TARGET_ASM_SELECT_SECTION.  */
6486 
6487 bool
have_global_bss_p(void)6488 have_global_bss_p (void)
6489 {
6490   return bss_noswitch_section || targetm.have_switchable_bss_sections;
6491 }
6492 
6493 /* Output assembly to switch to section NAME with attribute FLAGS.
6494    Four variants for common object file formats.  */
6495 
6496 void
default_no_named_section(const char * name ATTRIBUTE_UNUSED,unsigned int flags ATTRIBUTE_UNUSED,tree decl ATTRIBUTE_UNUSED)6497 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6498 			  unsigned int flags ATTRIBUTE_UNUSED,
6499 			  tree decl ATTRIBUTE_UNUSED)
6500 {
6501   /* Some object formats don't support named sections at all.  The
6502      front-end should already have flagged this as an error.  */
6503   gcc_unreachable ();
6504 }
6505 
6506 #ifndef TLS_SECTION_ASM_FLAG
6507 #define TLS_SECTION_ASM_FLAG 'T'
6508 #endif
6509 
6510 void
default_elf_asm_named_section(const char * name,unsigned int flags,tree decl)6511 default_elf_asm_named_section (const char *name, unsigned int flags,
6512 			       tree decl)
6513 {
6514   char flagchars[11], *f = flagchars;
6515   unsigned int numeric_value = 0;
6516 
6517   /* If we have already declared this section, we can use an
6518      abbreviated form to switch back to it -- unless this section is
6519      part of a COMDAT groups, in which case GAS requires the full
6520      declaration every time.  */
6521   if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6522       && (flags & SECTION_DECLARED))
6523     {
6524       fprintf (asm_out_file, "\t.section\t%s\n", name);
6525       return;
6526     }
6527 
6528   /* If we have a machine specific flag, then use the numeric value to pass
6529      this on to GAS.  */
6530   if (targetm.asm_out.elf_flags_numeric (flags, &numeric_value))
6531       snprintf (f, sizeof (flagchars), "0x%08x", numeric_value);
6532   else
6533     {
6534       if (!(flags & SECTION_DEBUG))
6535 	*f++ = 'a';
6536 #if HAVE_GAS_SECTION_EXCLUDE
6537       if (flags & SECTION_EXCLUDE)
6538 	*f++ = 'e';
6539 #endif
6540       if (flags & SECTION_WRITE)
6541 	*f++ = 'w';
6542       if (flags & SECTION_CODE)
6543 	*f++ = 'x';
6544       if (flags & SECTION_SMALL)
6545 	*f++ = 's';
6546       if (flags & SECTION_MERGE)
6547 	*f++ = 'M';
6548       if (flags & SECTION_STRINGS)
6549 	*f++ = 'S';
6550       if (flags & SECTION_TLS)
6551 	*f++ = TLS_SECTION_ASM_FLAG;
6552       if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6553 	*f++ = 'G';
6554 #ifdef MACH_DEP_SECTION_ASM_FLAG
6555       if (flags & SECTION_MACH_DEP)
6556 	*f++ = MACH_DEP_SECTION_ASM_FLAG;
6557 #endif
6558       *f = '\0';
6559     }
6560 
6561   fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6562 
6563   /* default_section_type_flags (above) knows which flags need special
6564      handling here, and sets NOTYPE when none of these apply so that the
6565      assembler's logic for default types can apply to user-chosen
6566      section names.  */
6567   if (!(flags & SECTION_NOTYPE))
6568     {
6569       const char *type;
6570       const char *format;
6571 
6572       if (flags & SECTION_BSS)
6573 	type = "nobits";
6574       else
6575 	type = "progbits";
6576 
6577       format = ",@%s";
6578       /* On platforms that use "@" as the assembly comment character,
6579 	 use "%" instead.  */
6580       if (strcmp (ASM_COMMENT_START, "@") == 0)
6581 	format = ",%%%s";
6582       fprintf (asm_out_file, format, type);
6583 
6584       if (flags & SECTION_ENTSIZE)
6585 	fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6586       if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6587 	{
6588 	  if (TREE_CODE (decl) == IDENTIFIER_NODE)
6589 	    fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6590 	  else
6591 	    fprintf (asm_out_file, ",%s,comdat",
6592 		     IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6593 	}
6594     }
6595 
6596   putc ('\n', asm_out_file);
6597 }
6598 
6599 void
default_coff_asm_named_section(const char * name,unsigned int flags,tree decl ATTRIBUTE_UNUSED)6600 default_coff_asm_named_section (const char *name, unsigned int flags,
6601 				tree decl ATTRIBUTE_UNUSED)
6602 {
6603   char flagchars[8], *f = flagchars;
6604 
6605   if (flags & SECTION_WRITE)
6606     *f++ = 'w';
6607   if (flags & SECTION_CODE)
6608     *f++ = 'x';
6609   *f = '\0';
6610 
6611   fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6612 }
6613 
6614 void
default_pe_asm_named_section(const char * name,unsigned int flags,tree decl)6615 default_pe_asm_named_section (const char *name, unsigned int flags,
6616 			      tree decl)
6617 {
6618   default_coff_asm_named_section (name, flags, decl);
6619 
6620   if (flags & SECTION_LINKONCE)
6621     {
6622       /* Functions may have been compiled at various levels of
6623          optimization so we can't use `same_size' here.
6624          Instead, have the linker pick one.  */
6625       fprintf (asm_out_file, "\t.linkonce %s\n",
6626 	       (flags & SECTION_CODE ? "discard" : "same_size"));
6627     }
6628 }
6629 
6630 /* The lame default section selector.  */
6631 
6632 section *
default_select_section(tree decl,int reloc,unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)6633 default_select_section (tree decl, int reloc,
6634 			unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6635 {
6636   if (DECL_P (decl))
6637     {
6638       if (decl_readonly_section (decl, reloc))
6639 	return readonly_data_section;
6640     }
6641   else if (TREE_CODE (decl) == CONSTRUCTOR)
6642     {
6643       if (! ((flag_pic && reloc)
6644 	     || !TREE_READONLY (decl)
6645 	     || TREE_SIDE_EFFECTS (decl)
6646 	     || !TREE_CONSTANT (decl)))
6647 	return readonly_data_section;
6648     }
6649   else if (TREE_CODE (decl) == STRING_CST)
6650     return readonly_data_section;
6651   else if (! (flag_pic && reloc))
6652     return readonly_data_section;
6653 
6654   return data_section;
6655 }
6656 
6657 enum section_category
categorize_decl_for_section(const_tree decl,int reloc)6658 categorize_decl_for_section (const_tree decl, int reloc)
6659 {
6660   enum section_category ret;
6661 
6662   if (TREE_CODE (decl) == FUNCTION_DECL)
6663     return SECCAT_TEXT;
6664   else if (TREE_CODE (decl) == STRING_CST)
6665     {
6666       if ((flag_sanitize & SANITIZE_ADDRESS)
6667 	  && asan_protect_global (CONST_CAST_TREE (decl)))
6668       /* or !flag_merge_constants */
6669         return SECCAT_RODATA;
6670       else
6671 	return SECCAT_RODATA_MERGE_STR;
6672     }
6673   else if (VAR_P (decl))
6674     {
6675       tree d = CONST_CAST_TREE (decl);
6676       if (bss_initializer_p (decl))
6677 	ret = SECCAT_BSS;
6678       else if (! TREE_READONLY (decl)
6679 	       || TREE_SIDE_EFFECTS (decl)
6680 	       || (DECL_INITIAL (decl)
6681 		   && ! TREE_CONSTANT (DECL_INITIAL (decl))))
6682 	{
6683 	  /* Here the reloc_rw_mask is not testing whether the section should
6684 	     be read-only or not, but whether the dynamic link will have to
6685 	     do something.  If so, we wish to segregate the data in order to
6686 	     minimize cache misses inside the dynamic linker.  */
6687 	  if (reloc & targetm.asm_out.reloc_rw_mask ())
6688 	    ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6689 	  else
6690 	    ret = SECCAT_DATA;
6691 	}
6692       else if (reloc & targetm.asm_out.reloc_rw_mask ())
6693 	ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6694       else if (reloc || flag_merge_constants < 2
6695 	       || ((flag_sanitize & SANITIZE_ADDRESS)
6696 		   /* PR 81697: for architectures that use section anchors we
6697 		      need to ignore DECL_RTL_SET_P (decl) for string constants
6698 		      inside this asan_protect_global call because otherwise
6699 		      we'll wrongly put them into SECCAT_RODATA_MERGE_CONST
6700 		      section, set DECL_RTL (decl) later on and add DECL to
6701 		      protected globals via successive asan_protect_global
6702 		      calls.  In this scenario we'll end up with wrong
6703 		      alignment of these strings at runtime and possible ASan
6704 		      false positives.  */
6705 		   && asan_protect_global (d, use_object_blocks_p ()
6706 					      && use_blocks_for_decl_p (d))))
6707 	/* C and C++ don't allow different variables to share the same
6708 	   location.  -fmerge-all-constants allows even that (at the
6709 	   expense of not conforming).  */
6710 	ret = SECCAT_RODATA;
6711       else if (DECL_INITIAL (decl)
6712 	       && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6713 	ret = SECCAT_RODATA_MERGE_STR_INIT;
6714       else
6715 	ret = SECCAT_RODATA_MERGE_CONST;
6716     }
6717   else if (TREE_CODE (decl) == CONSTRUCTOR)
6718     {
6719       if ((reloc & targetm.asm_out.reloc_rw_mask ())
6720 	  || TREE_SIDE_EFFECTS (decl)
6721 	  || ! TREE_CONSTANT (decl))
6722 	ret = SECCAT_DATA;
6723       else
6724 	ret = SECCAT_RODATA;
6725     }
6726   else
6727     ret = SECCAT_RODATA;
6728 
6729   /* There are no read-only thread-local sections.  */
6730   if (VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6731     {
6732       /* Note that this would be *just* SECCAT_BSS, except that there's
6733 	 no concept of a read-only thread-local-data section.  */
6734       if (ret == SECCAT_BSS
6735 	  || DECL_INITIAL (decl) == NULL
6736 	  || (flag_zero_initialized_in_bss
6737 	      && initializer_zerop (DECL_INITIAL (decl))))
6738 	ret = SECCAT_TBSS;
6739       else
6740 	ret = SECCAT_TDATA;
6741     }
6742 
6743   /* If the target uses small data sections, select it.  */
6744   else if (targetm.in_small_data_p (decl))
6745     {
6746       if (ret == SECCAT_BSS)
6747 	ret = SECCAT_SBSS;
6748       else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6749 	ret = SECCAT_SRODATA;
6750       else
6751 	ret = SECCAT_SDATA;
6752     }
6753 
6754   return ret;
6755 }
6756 
6757 static bool
decl_readonly_section_1(enum section_category category)6758 decl_readonly_section_1 (enum section_category category)
6759 {
6760   switch (category)
6761     {
6762     case SECCAT_RODATA:
6763     case SECCAT_RODATA_MERGE_STR:
6764     case SECCAT_RODATA_MERGE_STR_INIT:
6765     case SECCAT_RODATA_MERGE_CONST:
6766     case SECCAT_SRODATA:
6767       return true;
6768     default:
6769       return false;
6770     }
6771 }
6772 
6773 bool
decl_readonly_section(const_tree decl,int reloc)6774 decl_readonly_section (const_tree decl, int reloc)
6775 {
6776   return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6777 }
6778 
6779 /* Select a section based on the above categorization.  */
6780 
6781 section *
default_elf_select_section(tree decl,int reloc,unsigned HOST_WIDE_INT align)6782 default_elf_select_section (tree decl, int reloc,
6783 			    unsigned HOST_WIDE_INT align)
6784 {
6785   const char *sname;
6786   switch (categorize_decl_for_section (decl, reloc))
6787     {
6788     case SECCAT_TEXT:
6789       /* We're not supposed to be called on FUNCTION_DECLs.  */
6790       gcc_unreachable ();
6791     case SECCAT_RODATA:
6792       return readonly_data_section;
6793     case SECCAT_RODATA_MERGE_STR:
6794       return mergeable_string_section (decl, align, 0);
6795     case SECCAT_RODATA_MERGE_STR_INIT:
6796       return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6797     case SECCAT_RODATA_MERGE_CONST:
6798       return mergeable_constant_section (DECL_MODE (decl), align, 0);
6799     case SECCAT_SRODATA:
6800       sname = ".sdata2";
6801       break;
6802     case SECCAT_DATA:
6803       return data_section;
6804     case SECCAT_DATA_REL:
6805       sname = ".data.rel";
6806       break;
6807     case SECCAT_DATA_REL_LOCAL:
6808       sname = ".data.rel.local";
6809       break;
6810     case SECCAT_DATA_REL_RO:
6811       sname = ".data.rel.ro";
6812       break;
6813     case SECCAT_DATA_REL_RO_LOCAL:
6814       sname = ".data.rel.ro.local";
6815       break;
6816     case SECCAT_SDATA:
6817       sname = ".sdata";
6818       break;
6819     case SECCAT_TDATA:
6820       sname = ".tdata";
6821       break;
6822     case SECCAT_BSS:
6823       if (bss_section)
6824 	return bss_section;
6825       sname = ".bss";
6826       break;
6827     case SECCAT_SBSS:
6828       sname = ".sbss";
6829       break;
6830     case SECCAT_TBSS:
6831       sname = ".tbss";
6832       break;
6833     default:
6834       gcc_unreachable ();
6835     }
6836 
6837   return get_named_section (decl, sname, reloc);
6838 }
6839 
6840 /* Construct a unique section name based on the decl name and the
6841    categorization performed above.  */
6842 
6843 void
default_unique_section(tree decl,int reloc)6844 default_unique_section (tree decl, int reloc)
6845 {
6846   /* We only need to use .gnu.linkonce if we don't have COMDAT groups.  */
6847   bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6848   const char *prefix, *name, *linkonce;
6849   char *string;
6850   tree id;
6851 
6852   switch (categorize_decl_for_section (decl, reloc))
6853     {
6854     case SECCAT_TEXT:
6855       prefix = one_only ? ".t" : ".text";
6856       break;
6857     case SECCAT_RODATA:
6858     case SECCAT_RODATA_MERGE_STR:
6859     case SECCAT_RODATA_MERGE_STR_INIT:
6860     case SECCAT_RODATA_MERGE_CONST:
6861       prefix = one_only ? ".r" : ".rodata";
6862       break;
6863     case SECCAT_SRODATA:
6864       prefix = one_only ? ".s2" : ".sdata2";
6865       break;
6866     case SECCAT_DATA:
6867       prefix = one_only ? ".d" : ".data";
6868       break;
6869     case SECCAT_DATA_REL:
6870       prefix = one_only ? ".d.rel" : ".data.rel";
6871       break;
6872     case SECCAT_DATA_REL_LOCAL:
6873       prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6874       break;
6875     case SECCAT_DATA_REL_RO:
6876       prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6877       break;
6878     case SECCAT_DATA_REL_RO_LOCAL:
6879       prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6880       break;
6881     case SECCAT_SDATA:
6882       prefix = one_only ? ".s" : ".sdata";
6883       break;
6884     case SECCAT_BSS:
6885       prefix = one_only ? ".b" : ".bss";
6886       break;
6887     case SECCAT_SBSS:
6888       prefix = one_only ? ".sb" : ".sbss";
6889       break;
6890     case SECCAT_TDATA:
6891       prefix = one_only ? ".td" : ".tdata";
6892       break;
6893     case SECCAT_TBSS:
6894       prefix = one_only ? ".tb" : ".tbss";
6895       break;
6896     default:
6897       gcc_unreachable ();
6898     }
6899 
6900   id = DECL_ASSEMBLER_NAME (decl);
6901   ultimate_transparent_alias_target (&id);
6902   name = IDENTIFIER_POINTER (id);
6903   name = targetm.strip_name_encoding (name);
6904 
6905   /* If we're using one_only, then there needs to be a .gnu.linkonce
6906      prefix to the section name.  */
6907   linkonce = one_only ? ".gnu.linkonce" : "";
6908 
6909   string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6910 
6911   set_decl_section_name (decl, string);
6912 }
6913 
6914 /* Subroutine of compute_reloc_for_rtx for leaf rtxes.  */
6915 
6916 static int
compute_reloc_for_rtx_1(const_rtx x)6917 compute_reloc_for_rtx_1 (const_rtx x)
6918 {
6919   switch (GET_CODE (x))
6920     {
6921     case SYMBOL_REF:
6922       return SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6923     case LABEL_REF:
6924       return 1;
6925     default:
6926       return 0;
6927     }
6928 }
6929 
6930 /* Like compute_reloc_for_constant, except for an RTX.  The return value
6931    is a mask for which bit 1 indicates a global relocation, and bit 0
6932    indicates a local relocation.  */
6933 
6934 static int
compute_reloc_for_rtx(const_rtx x)6935 compute_reloc_for_rtx (const_rtx x)
6936 {
6937   switch (GET_CODE (x))
6938     {
6939     case SYMBOL_REF:
6940     case LABEL_REF:
6941       return compute_reloc_for_rtx_1 (x);
6942 
6943     case CONST:
6944       {
6945 	int reloc = 0;
6946 	subrtx_iterator::array_type array;
6947 	FOR_EACH_SUBRTX (iter, array, x, ALL)
6948 	  reloc |= compute_reloc_for_rtx_1 (*iter);
6949 	return reloc;
6950       }
6951 
6952     default:
6953       return 0;
6954     }
6955 }
6956 
6957 section *
default_select_rtx_section(machine_mode mode ATTRIBUTE_UNUSED,rtx x,unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)6958 default_select_rtx_section (machine_mode mode ATTRIBUTE_UNUSED,
6959 			    rtx x,
6960 			    unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6961 {
6962   if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6963     return data_section;
6964   else
6965     return readonly_data_section;
6966 }
6967 
6968 section *
default_elf_select_rtx_section(machine_mode mode,rtx x,unsigned HOST_WIDE_INT align)6969 default_elf_select_rtx_section (machine_mode mode, rtx x,
6970 				unsigned HOST_WIDE_INT align)
6971 {
6972   int reloc = compute_reloc_for_rtx (x);
6973 
6974   /* ??? Handle small data here somehow.  */
6975 
6976   if (reloc & targetm.asm_out.reloc_rw_mask ())
6977     {
6978       if (reloc == 1)
6979 	return get_named_section (NULL, ".data.rel.ro.local", 1);
6980       else
6981 	return get_named_section (NULL, ".data.rel.ro", 3);
6982     }
6983 
6984   return mergeable_constant_section (mode, align, 0);
6985 }
6986 
6987 /* Set the generally applicable flags on the SYMBOL_REF for EXP.  */
6988 
6989 void
default_encode_section_info(tree decl,rtx rtl,int first ATTRIBUTE_UNUSED)6990 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6991 {
6992   rtx symbol;
6993   int flags;
6994 
6995   /* Careful not to prod global register variables.  */
6996   if (!MEM_P (rtl))
6997     return;
6998   symbol = XEXP (rtl, 0);
6999   if (GET_CODE (symbol) != SYMBOL_REF)
7000     return;
7001 
7002   flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
7003   if (TREE_CODE (decl) == FUNCTION_DECL)
7004     flags |= SYMBOL_FLAG_FUNCTION;
7005   if (targetm.binds_local_p (decl))
7006     flags |= SYMBOL_FLAG_LOCAL;
7007   if (VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
7008     flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
7009   else if (targetm.in_small_data_p (decl))
7010     flags |= SYMBOL_FLAG_SMALL;
7011   /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names?  Without
7012      being PUBLIC, the thing *must* be defined in this translation unit.
7013      Prevent this buglet from being propagated into rtl code as well.  */
7014   if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
7015     flags |= SYMBOL_FLAG_EXTERNAL;
7016 
7017   SYMBOL_REF_FLAGS (symbol) = flags;
7018 }
7019 
7020 /* By default, we do nothing for encode_section_info, so we need not
7021    do anything but discard the '*' marker.  */
7022 
7023 const char *
default_strip_name_encoding(const char * str)7024 default_strip_name_encoding (const char *str)
7025 {
7026   return str + (*str == '*');
7027 }
7028 
7029 #ifdef ASM_OUTPUT_DEF
7030 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR.  Define the
7031    anchor relative to ".", the current section position.  */
7032 
7033 void
default_asm_output_anchor(rtx symbol)7034 default_asm_output_anchor (rtx symbol)
7035 {
7036   char buffer[100];
7037 
7038   sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
7039 	   SYMBOL_REF_BLOCK_OFFSET (symbol));
7040   ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
7041 }
7042 #endif
7043 
7044 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P.  */
7045 
7046 bool
default_use_anchors_for_symbol_p(const_rtx symbol)7047 default_use_anchors_for_symbol_p (const_rtx symbol)
7048 {
7049   tree decl;
7050   section *sect = SYMBOL_REF_BLOCK (symbol)->sect;
7051 
7052   /* This function should only be called with non-zero SYMBOL_REF_BLOCK,
7053      furthermore get_block_for_section should not create object blocks
7054      for mergeable sections.  */
7055   gcc_checking_assert (sect && !(sect->common.flags & SECTION_MERGE));
7056 
7057   /* Don't use anchors for small data sections.  The small data register
7058      acts as an anchor for such sections.  */
7059   if (sect->common.flags & SECTION_SMALL)
7060     return false;
7061 
7062   decl = SYMBOL_REF_DECL (symbol);
7063   if (decl && DECL_P (decl))
7064     {
7065       /* Don't use section anchors for decls that might be defined or
7066 	 usurped by other modules.  */
7067       if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
7068 	return false;
7069 
7070       /* Don't use section anchors for decls that will be placed in a
7071 	 small data section.  */
7072       /* ??? Ideally, this check would be redundant with the SECTION_SMALL
7073 	 one above.  The problem is that we only use SECTION_SMALL for
7074 	 sections that should be marked as small in the section directive.  */
7075       if (targetm.in_small_data_p (decl))
7076 	return false;
7077 
7078       /* Don't use section anchors for decls that won't fit inside a single
7079 	 anchor range to reduce the amount of instructions required to refer
7080 	 to the entire declaration.  */
7081       if (DECL_SIZE_UNIT (decl) == NULL_TREE
7082 	  || !tree_fits_uhwi_p (DECL_SIZE_UNIT (decl))
7083 	  || (tree_to_uhwi (DECL_SIZE_UNIT (decl))
7084 	      >= (unsigned HOST_WIDE_INT) targetm.max_anchor_offset))
7085 	return false;
7086 
7087     }
7088   return true;
7089 }
7090 
7091 /* Return true when RESOLUTION indicate that symbol will be bound to the
7092    definition provided by current .o file.  */
7093 
7094 static bool
resolution_to_local_definition_p(enum ld_plugin_symbol_resolution resolution)7095 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
7096 {
7097   return (resolution == LDPR_PREVAILING_DEF
7098 	  || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
7099 	  || resolution == LDPR_PREVAILING_DEF_IRONLY);
7100 }
7101 
7102 /* Return true when RESOLUTION indicate that symbol will be bound locally
7103    within current executable or DSO.  */
7104 
7105 static bool
resolution_local_p(enum ld_plugin_symbol_resolution resolution)7106 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
7107 {
7108   return (resolution == LDPR_PREVAILING_DEF
7109 	  || resolution == LDPR_PREVAILING_DEF_IRONLY
7110 	  || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
7111 	  || resolution == LDPR_PREEMPTED_REG
7112 	  || resolution == LDPR_PREEMPTED_IR
7113 	  || resolution == LDPR_RESOLVED_IR
7114 	  || resolution == LDPR_RESOLVED_EXEC);
7115 }
7116 
7117 /* COMMON_LOCAL_P is true means that the linker can guarantee that an
7118    uninitialized common symbol in the executable will still be defined
7119    (through COPY relocation) in the executable.  */
7120 
7121 bool
default_binds_local_p_3(const_tree exp,bool shlib,bool weak_dominate,bool extern_protected_data,bool common_local_p)7122 default_binds_local_p_3 (const_tree exp, bool shlib, bool weak_dominate,
7123 			 bool extern_protected_data, bool common_local_p)
7124 {
7125   /* A non-decl is an entry in the constant pool.  */
7126   if (!DECL_P (exp))
7127     return true;
7128 
7129   /* Weakrefs may not bind locally, even though the weakref itself is always
7130      static and therefore local.  Similarly, the resolver for ifunc functions
7131      might resolve to a non-local function.
7132      FIXME: We can resolve the weakref case more curefuly by looking at the
7133      weakref alias.  */
7134   if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
7135       || (TREE_CODE (exp) == FUNCTION_DECL
7136 	  && cgraph_node::get (exp)
7137 	  && cgraph_node::get (exp)->ifunc_resolver))
7138     return false;
7139 
7140   /* Static variables are always local.  */
7141   if (! TREE_PUBLIC (exp))
7142     return true;
7143 
7144   /* With resolution file in hand, take look into resolutions.
7145      We can't just return true for resolved_locally symbols,
7146      because dynamic linking might overwrite symbols
7147      in shared libraries.  */
7148   bool resolved_locally = false;
7149 
7150   bool uninited_common = (DECL_COMMON (exp)
7151 			  && (DECL_INITIAL (exp) == NULL
7152 			      || (!in_lto_p
7153 				  && DECL_INITIAL (exp) == error_mark_node)));
7154 
7155   /* A non-external variable is defined locally only if it isn't
7156      uninitialized COMMON variable or common_local_p is true.  */
7157   bool defined_locally = (!DECL_EXTERNAL (exp)
7158 			  && (!uninited_common || common_local_p));
7159   if (symtab_node *node = symtab_node::get (exp))
7160     {
7161       if (node->in_other_partition)
7162 	defined_locally = true;
7163       if (node->can_be_discarded_p ())
7164 	;
7165       else if (resolution_to_local_definition_p (node->resolution))
7166 	defined_locally = resolved_locally = true;
7167       else if (resolution_local_p (node->resolution))
7168 	resolved_locally = true;
7169     }
7170   if (defined_locally && weak_dominate && !shlib)
7171     resolved_locally = true;
7172 
7173   /* Undefined weak symbols are never defined locally.  */
7174   if (DECL_WEAK (exp) && !defined_locally)
7175     return false;
7176 
7177   /* A symbol is local if the user has said explicitly that it will be,
7178      or if we have a definition for the symbol.  We cannot infer visibility
7179      for undefined symbols.  */
7180   if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT
7181       && (TREE_CODE (exp) == FUNCTION_DECL
7182 	  || !extern_protected_data
7183 	  || DECL_VISIBILITY (exp) != VISIBILITY_PROTECTED)
7184       && (DECL_VISIBILITY_SPECIFIED (exp) || defined_locally))
7185     return true;
7186 
7187   /* If PIC, then assume that any global name can be overridden by
7188      symbols resolved from other modules.  */
7189   if (shlib)
7190     return false;
7191 
7192   /* Variables defined outside this object might not be local.  */
7193   if (DECL_EXTERNAL (exp) && !resolved_locally)
7194     return false;
7195 
7196   /* Non-dominant weak symbols are not defined locally.  */
7197   if (DECL_WEAK (exp) && !resolved_locally)
7198     return false;
7199 
7200   /* Uninitialized COMMON variable may be unified with symbols
7201      resolved from other modules.  */
7202   if (uninited_common && !resolved_locally)
7203     return false;
7204 
7205   /* Otherwise we're left with initialized (or non-common) global data
7206      which is of necessity defined locally.  */
7207   return true;
7208 }
7209 
7210 /* Assume ELF-ish defaults, since that's pretty much the most liberal
7211    wrt cross-module name binding.  */
7212 
7213 bool
default_binds_local_p(const_tree exp)7214 default_binds_local_p (const_tree exp)
7215 {
7216   return default_binds_local_p_3 (exp, flag_shlib != 0, true, false, false);
7217 }
7218 
7219 /* Similar to default_binds_local_p, but common symbol may be local and
7220    extern protected data is non-local.  */
7221 
7222 bool
default_binds_local_p_2(const_tree exp)7223 default_binds_local_p_2 (const_tree exp)
7224 {
7225   return default_binds_local_p_3 (exp, flag_shlib != 0, true, true,
7226 				  !flag_pic);
7227 }
7228 
7229 bool
default_binds_local_p_1(const_tree exp,int shlib)7230 default_binds_local_p_1 (const_tree exp, int shlib)
7231 {
7232   return default_binds_local_p_3 (exp, shlib != 0, false, false, false);
7233 }
7234 
7235 /* Return true when references to DECL must bind to current definition in
7236    final executable.
7237 
7238    The condition is usually equivalent to whether the function binds to the
7239    current module (shared library or executable), that is to binds_local_p.
7240    We use this fact to avoid need for another target hook and implement
7241    the logic using binds_local_p and just special cases where
7242    decl_binds_to_current_def_p is stronger than binds_local_p.  In particular
7243    the weak definitions (that can be overwritten at linktime by other
7244    definition from different object file) and when resolution info is available
7245    we simply use the knowledge passed to us by linker plugin.  */
7246 bool
decl_binds_to_current_def_p(const_tree decl)7247 decl_binds_to_current_def_p (const_tree decl)
7248 {
7249   gcc_assert (DECL_P (decl));
7250   if (!targetm.binds_local_p (decl))
7251     return false;
7252   if (!TREE_PUBLIC (decl))
7253     return true;
7254 
7255   /* When resolution is available, just use it.  */
7256   if (symtab_node *node = symtab_node::get (decl))
7257     {
7258       if (node->resolution != LDPR_UNKNOWN
7259 	  && !node->can_be_discarded_p ())
7260 	return resolution_to_local_definition_p (node->resolution);
7261     }
7262 
7263   /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
7264      binds locally but still can be overwritten), DECL_COMMON (can be merged
7265      with a non-common definition somewhere in the same module) or
7266      DECL_EXTERNAL.
7267      This rely on fact that binds_local_p behave as decl_replaceable_p
7268      for all other declaration types.  */
7269   if (DECL_WEAK (decl))
7270     return false;
7271   if (DECL_COMMON (decl)
7272       && (DECL_INITIAL (decl) == NULL
7273 	  || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
7274     return false;
7275   if (DECL_EXTERNAL (decl))
7276     return false;
7277   return true;
7278 }
7279 
7280 /* A replaceable function or variable is one which may be replaced
7281    at link-time with an entirely different definition, provided that the
7282    replacement has the same type.  For example, functions declared
7283    with __attribute__((weak)) on most systems are replaceable.
7284 
7285    COMDAT functions are not replaceable, since all definitions of the
7286    function must be equivalent.  It is important that COMDAT functions
7287    not be treated as replaceable so that use of C++ template
7288    instantiations is not penalized.  */
7289 
7290 bool
decl_replaceable_p(tree decl)7291 decl_replaceable_p (tree decl)
7292 {
7293   gcc_assert (DECL_P (decl));
7294   if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
7295     return false;
7296   if (!flag_semantic_interposition
7297       && !DECL_WEAK (decl))
7298     return false;
7299   return !decl_binds_to_current_def_p (decl);
7300 }
7301 
7302 /* Default function to output code that will globalize a label.  A
7303    target must define GLOBAL_ASM_OP or provide its own function to
7304    globalize a label.  */
7305 #ifdef GLOBAL_ASM_OP
7306 void
default_globalize_label(FILE * stream,const char * name)7307 default_globalize_label (FILE * stream, const char *name)
7308 {
7309   fputs (GLOBAL_ASM_OP, stream);
7310   assemble_name (stream, name);
7311   putc ('\n', stream);
7312 }
7313 #endif /* GLOBAL_ASM_OP */
7314 
7315 /* Default function to output code that will globalize a declaration.  */
7316 void
default_globalize_decl_name(FILE * stream,tree decl)7317 default_globalize_decl_name (FILE * stream, tree decl)
7318 {
7319   const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
7320   targetm.asm_out.globalize_label (stream, name);
7321 }
7322 
7323 /* Default function to output a label for unwind information.  The
7324    default is to do nothing.  A target that needs nonlocal labels for
7325    unwind information must provide its own function to do this.  */
7326 void
default_emit_unwind_label(FILE * stream ATTRIBUTE_UNUSED,tree decl ATTRIBUTE_UNUSED,int for_eh ATTRIBUTE_UNUSED,int empty ATTRIBUTE_UNUSED)7327 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
7328 			   tree decl ATTRIBUTE_UNUSED,
7329 			   int for_eh ATTRIBUTE_UNUSED,
7330 			   int empty ATTRIBUTE_UNUSED)
7331 {
7332 }
7333 
7334 /* Default function to output a label to divide up the exception table.
7335    The default is to do nothing.  A target that needs/wants to divide
7336    up the table must provide it's own function to do this.  */
7337 void
default_emit_except_table_label(FILE * stream ATTRIBUTE_UNUSED)7338 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
7339 {
7340 }
7341 
7342 /* This is how to output an internal numbered label where PREFIX is
7343    the class of label and LABELNO is the number within the class.  */
7344 
7345 void
default_generate_internal_label(char * buf,const char * prefix,unsigned long labelno)7346 default_generate_internal_label (char *buf, const char *prefix,
7347 				 unsigned long labelno)
7348 {
7349   ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
7350 }
7351 
7352 /* This is how to output an internal numbered label where PREFIX is
7353    the class of label and LABELNO is the number within the class.  */
7354 
7355 void
default_internal_label(FILE * stream,const char * prefix,unsigned long labelno)7356 default_internal_label (FILE *stream, const char *prefix,
7357 			unsigned long labelno)
7358 {
7359   char *const buf = (char *) alloca (40 + strlen (prefix));
7360   ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
7361   ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
7362 }
7363 
7364 
7365 /* The default implementation of ASM_DECLARE_CONSTANT_NAME.  */
7366 
7367 void
default_asm_declare_constant_name(FILE * file,const char * name,const_tree exp ATTRIBUTE_UNUSED,HOST_WIDE_INT size ATTRIBUTE_UNUSED)7368 default_asm_declare_constant_name (FILE *file, const char *name,
7369 				   const_tree exp ATTRIBUTE_UNUSED,
7370 				   HOST_WIDE_INT size ATTRIBUTE_UNUSED)
7371 {
7372   assemble_label (file, name);
7373 }
7374 
7375 /* This is the default behavior at the beginning of a file.  It's
7376    controlled by two other target-hook toggles.  */
7377 void
default_file_start(void)7378 default_file_start (void)
7379 {
7380   if (targetm.asm_file_start_app_off
7381       && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
7382     fputs (ASM_APP_OFF, asm_out_file);
7383 
7384   if (targetm.asm_file_start_file_directive)
7385     {
7386       /* LTO produced units have no meaningful main_input_filename.  */
7387       if (in_lto_p)
7388 	output_file_directive (asm_out_file, "<artificial>");
7389       else
7390 	output_file_directive (asm_out_file, main_input_filename);
7391     }
7392 }
7393 
7394 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
7395    which emits a special section directive used to indicate whether or
7396    not this object file needs an executable stack.  This is primarily
7397    a GNU extension to ELF but could be used on other targets.  */
7398 
7399 int trampolines_created;
7400 
7401 void
file_end_indicate_exec_stack(void)7402 file_end_indicate_exec_stack (void)
7403 {
7404   unsigned int flags = SECTION_DEBUG;
7405   if (trampolines_created)
7406     flags |= SECTION_CODE;
7407 
7408   switch_to_section (get_section (".note.GNU-stack", flags, NULL));
7409 }
7410 
7411 /* Emit a special section directive to indicate that this object file
7412    was compiled with -fsplit-stack.  This is used to let the linker
7413    detect calls between split-stack code and non-split-stack code, so
7414    that it can modify the split-stack code to allocate a sufficiently
7415    large stack.  We emit another special section if there are any
7416    functions in this file which have the no_split_stack attribute, to
7417    prevent the linker from warning about being unable to convert the
7418    functions if they call non-split-stack code.  */
7419 
7420 void
file_end_indicate_split_stack(void)7421 file_end_indicate_split_stack (void)
7422 {
7423   if (flag_split_stack)
7424     {
7425       switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
7426 				      NULL));
7427       if (saw_no_split_stack)
7428 	switch_to_section (get_section (".note.GNU-no-split-stack",
7429 					SECTION_DEBUG, NULL));
7430     }
7431 }
7432 
7433 /* Output DIRECTIVE (a C string) followed by a newline.  This is used as
7434    a get_unnamed_section callback.  */
7435 
7436 void
output_section_asm_op(const void * directive)7437 output_section_asm_op (const void *directive)
7438 {
7439   fprintf (asm_out_file, "%s\n", (const char *) directive);
7440 }
7441 
7442 /* Emit assembly code to switch to section NEW_SECTION.  Do nothing if
7443    the current section is NEW_SECTION.  */
7444 
7445 void
switch_to_section(section * new_section)7446 switch_to_section (section *new_section)
7447 {
7448   if (in_section == new_section)
7449     return;
7450 
7451   if (new_section->common.flags & SECTION_FORGET)
7452     in_section = NULL;
7453   else
7454     in_section = new_section;
7455 
7456   switch (SECTION_STYLE (new_section))
7457     {
7458     case SECTION_NAMED:
7459       targetm.asm_out.named_section (new_section->named.name,
7460 				     new_section->named.common.flags,
7461 				     new_section->named.decl);
7462       break;
7463 
7464     case SECTION_UNNAMED:
7465       new_section->unnamed.callback (new_section->unnamed.data);
7466       break;
7467 
7468     case SECTION_NOSWITCH:
7469       gcc_unreachable ();
7470       break;
7471     }
7472 
7473   new_section->common.flags |= SECTION_DECLARED;
7474 }
7475 
7476 /* If block symbol SYMBOL has not yet been assigned an offset, place
7477    it at the end of its block.  */
7478 
7479 void
place_block_symbol(rtx symbol)7480 place_block_symbol (rtx symbol)
7481 {
7482   unsigned HOST_WIDE_INT size, mask, offset;
7483   struct constant_descriptor_rtx *desc;
7484   unsigned int alignment;
7485   struct object_block *block;
7486   tree decl;
7487 
7488   gcc_assert (SYMBOL_REF_BLOCK (symbol));
7489   if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7490     return;
7491 
7492   /* Work out the symbol's size and alignment.  */
7493   if (CONSTANT_POOL_ADDRESS_P (symbol))
7494     {
7495       desc = SYMBOL_REF_CONSTANT (symbol);
7496       alignment = desc->align;
7497       size = GET_MODE_SIZE (desc->mode);
7498     }
7499   else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7500     {
7501       decl = SYMBOL_REF_DECL (symbol);
7502       gcc_checking_assert (DECL_IN_CONSTANT_POOL (decl));
7503       alignment = DECL_ALIGN (decl);
7504       size = get_constant_size (DECL_INITIAL (decl));
7505       if ((flag_sanitize & SANITIZE_ADDRESS)
7506 	  && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7507 	  && asan_protect_global (DECL_INITIAL (decl)))
7508 	{
7509 	  size += asan_red_zone_size (size);
7510 	  alignment = MAX (alignment,
7511 			   ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7512 	}
7513     }
7514   else
7515     {
7516       struct symtab_node *snode;
7517       decl = SYMBOL_REF_DECL (symbol);
7518 
7519       snode = symtab_node::get (decl);
7520       if (snode->alias)
7521 	{
7522 	  rtx target = DECL_RTL (snode->ultimate_alias_target ()->decl);
7523 
7524 	  gcc_assert (MEM_P (target)
7525 		      && GET_CODE (XEXP (target, 0)) == SYMBOL_REF
7526 		      && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (target, 0)));
7527 	  target = XEXP (target, 0);
7528 	  place_block_symbol (target);
7529 	  SYMBOL_REF_BLOCK_OFFSET (symbol) = SYMBOL_REF_BLOCK_OFFSET (target);
7530 	  return;
7531 	}
7532       alignment = get_variable_align (decl);
7533       size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7534       if ((flag_sanitize & SANITIZE_ADDRESS)
7535 	  && asan_protect_global (decl))
7536 	{
7537 	  size += asan_red_zone_size (size);
7538 	  alignment = MAX (alignment,
7539 			   ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7540 	}
7541     }
7542 
7543   /* Calculate the object's offset from the start of the block.  */
7544   block = SYMBOL_REF_BLOCK (symbol);
7545   mask = alignment / BITS_PER_UNIT - 1;
7546   offset = (block->size + mask) & ~mask;
7547   SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7548 
7549   /* Record the block's new alignment and size.  */
7550   block->alignment = MAX (block->alignment, alignment);
7551   block->size = offset + size;
7552 
7553   vec_safe_push (block->objects, symbol);
7554 }
7555 
7556 /* Return the anchor that should be used to address byte offset OFFSET
7557    from the first object in BLOCK.  MODEL is the TLS model used
7558    to access it.  */
7559 
7560 rtx
get_section_anchor(struct object_block * block,HOST_WIDE_INT offset,enum tls_model model)7561 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7562 		    enum tls_model model)
7563 {
7564   char label[100];
7565   unsigned int begin, middle, end;
7566   unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7567   rtx anchor;
7568 
7569   /* Work out the anchor's offset.  Use an offset of 0 for the first
7570      anchor so that we don't pessimize the case where we take the address
7571      of a variable at the beginning of the block.  This is particularly
7572      useful when a block has only one variable assigned to it.
7573 
7574      We try to place anchors RANGE bytes apart, so there can then be
7575      anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7576      a ptr_mode offset.  With some target settings, the lowest such
7577      anchor might be out of range for the lowest ptr_mode offset;
7578      likewise the highest anchor for the highest offset.  Use anchors
7579      at the extreme ends of the ptr_mode range in such cases.
7580 
7581      All arithmetic uses unsigned integers in order to avoid
7582      signed overflow.  */
7583   max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7584   min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7585   range = max_offset - min_offset + 1;
7586   if (range == 0)
7587     offset = 0;
7588   else
7589     {
7590       bias = HOST_WIDE_INT_1U << (GET_MODE_BITSIZE (ptr_mode) - 1);
7591       if (offset < 0)
7592 	{
7593 	  delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7594 	  delta -= delta % range;
7595 	  if (delta > bias)
7596 	    delta = bias;
7597 	  offset = (HOST_WIDE_INT) (-delta);
7598 	}
7599       else
7600 	{
7601 	  delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7602 	  delta -= delta % range;
7603 	  if (delta > bias - 1)
7604 	    delta = bias - 1;
7605 	  offset = (HOST_WIDE_INT) delta;
7606 	}
7607     }
7608 
7609   /* Do a binary search to see if there's already an anchor we can use.
7610      Set BEGIN to the new anchor's index if not.  */
7611   begin = 0;
7612   end = vec_safe_length (block->anchors);
7613   while (begin != end)
7614     {
7615       middle = (end + begin) / 2;
7616       anchor = (*block->anchors)[middle];
7617       if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7618 	end = middle;
7619       else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7620 	begin = middle + 1;
7621       else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7622 	end = middle;
7623       else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7624 	begin = middle + 1;
7625       else
7626 	return anchor;
7627     }
7628 
7629   /* Create a new anchor with a unique label.  */
7630   ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7631   anchor = create_block_symbol (ggc_strdup (label), block, offset);
7632   SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7633   SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7634 
7635   /* Insert it at index BEGIN.  */
7636   vec_safe_insert (block->anchors, begin, anchor);
7637   return anchor;
7638 }
7639 
7640 /* Output the objects in BLOCK.  */
7641 
7642 static void
output_object_block(struct object_block * block)7643 output_object_block (struct object_block *block)
7644 {
7645   struct constant_descriptor_rtx *desc;
7646   unsigned int i;
7647   HOST_WIDE_INT offset;
7648   tree decl;
7649   rtx symbol;
7650 
7651   if (!block->objects)
7652     return;
7653 
7654   /* Switch to the section and make sure that the first byte is
7655      suitably aligned.  */
7656   /* Special case VTV comdat sections similar to assemble_variable.  */
7657   if (SECTION_STYLE (block->sect) == SECTION_NAMED
7658       && block->sect->named.name
7659       && (strcmp (block->sect->named.name, ".vtable_map_vars") == 0))
7660     handle_vtv_comdat_section (block->sect, block->sect->named.decl);
7661   else
7662     switch_to_section (block->sect);
7663 
7664   gcc_checking_assert (!(block->sect->common.flags & SECTION_MERGE));
7665   assemble_align (block->alignment);
7666 
7667   /* Define the values of all anchors relative to the current section
7668      position.  */
7669   FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7670     targetm.asm_out.output_anchor (symbol);
7671 
7672   /* Output the objects themselves.  */
7673   offset = 0;
7674   FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7675     {
7676       /* Move to the object's offset, padding with zeros if necessary.  */
7677       assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7678       offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7679       if (CONSTANT_POOL_ADDRESS_P (symbol))
7680 	{
7681 	  desc = SYMBOL_REF_CONSTANT (symbol);
7682 	  /* Pass 1 for align as we have already laid out everything in the block.
7683 	     So aligning shouldn't be necessary.  */
7684 	  output_constant_pool_1 (desc, 1);
7685 	  offset += GET_MODE_SIZE (desc->mode);
7686 	}
7687       else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7688 	{
7689 	  HOST_WIDE_INT size;
7690 	  decl = SYMBOL_REF_DECL (symbol);
7691 	  assemble_constant_contents (DECL_INITIAL (decl), XSTR (symbol, 0),
7692 				      DECL_ALIGN (decl), false);
7693 
7694 	  size = get_constant_size (DECL_INITIAL (decl));
7695 	  offset += size;
7696 	  if ((flag_sanitize & SANITIZE_ADDRESS)
7697 	      && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7698 	      && asan_protect_global (DECL_INITIAL (decl)))
7699 	    {
7700 	      size = asan_red_zone_size (size);
7701 	      assemble_zeros (size);
7702 	      offset += size;
7703 	    }
7704 	}
7705       else
7706 	{
7707 	  HOST_WIDE_INT size;
7708 	  decl = SYMBOL_REF_DECL (symbol);
7709 	  assemble_variable_contents (decl, XSTR (symbol, 0), false, false);
7710 	  size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7711 	  offset += size;
7712 	  if ((flag_sanitize & SANITIZE_ADDRESS)
7713 	      && asan_protect_global (decl))
7714 	    {
7715 	      size = asan_red_zone_size (size);
7716 	      assemble_zeros (size);
7717 	      offset += size;
7718 	    }
7719 	}
7720     }
7721 }
7722 
7723 /* A callback for qsort to compare object_blocks.  */
7724 
7725 static int
output_object_block_compare(const void * x,const void * y)7726 output_object_block_compare (const void *x, const void *y)
7727 {
7728   object_block *p1 = *(object_block * const*)x;
7729   object_block *p2 = *(object_block * const*)y;
7730 
7731   if (p1->sect->common.flags & SECTION_NAMED
7732       && !(p2->sect->common.flags & SECTION_NAMED))
7733     return 1;
7734 
7735   if (!(p1->sect->common.flags & SECTION_NAMED)
7736       && p2->sect->common.flags & SECTION_NAMED)
7737     return -1;
7738 
7739   if (p1->sect->common.flags & SECTION_NAMED
7740       && p2->sect->common.flags & SECTION_NAMED)
7741     return strcmp (p1->sect->named.name, p2->sect->named.name);
7742 
7743   unsigned f1 = p1->sect->common.flags;
7744   unsigned f2 = p2->sect->common.flags;
7745   if (f1 == f2)
7746     return 0;
7747   return f1 < f2 ? -1 : 1;
7748 }
7749 
7750 /* Output the definitions of all object_blocks.  */
7751 
7752 void
output_object_blocks(void)7753 output_object_blocks (void)
7754 {
7755   vec<object_block *, va_heap> v;
7756   v.create (object_block_htab->elements ());
7757   object_block *obj;
7758   hash_table<object_block_hasher>::iterator hi;
7759 
7760   FOR_EACH_HASH_TABLE_ELEMENT (*object_block_htab, obj, object_block *, hi)
7761     v.quick_push (obj);
7762 
7763   /* Sort them in order to output them in a deterministic manner,
7764      otherwise we may get .rodata sections in different orders with
7765      and without -g.  */
7766   v.qsort (output_object_block_compare);
7767   unsigned i;
7768   FOR_EACH_VEC_ELT (v, i, obj)
7769     output_object_block (obj);
7770 
7771   v.release ();
7772 }
7773 
7774 /* This function provides a possible implementation of the
7775    TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets.  When triggered
7776    by -frecord-gcc-switches it creates a new mergeable, string section in the
7777    assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7778    contains the switches in ASCII format.
7779 
7780    FIXME: This code does not correctly handle double quote characters
7781    that appear inside strings, (it strips them rather than preserving them).
7782    FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7783    characters - instead it treats them as sub-string separators.  Since
7784    we want to emit NUL strings terminators into the object file we have to use
7785    ASM_OUTPUT_SKIP.  */
7786 
7787 int
elf_record_gcc_switches(print_switch_type type,const char * name)7788 elf_record_gcc_switches (print_switch_type type, const char * name)
7789 {
7790   switch (type)
7791     {
7792     case SWITCH_TYPE_PASSED:
7793       ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7794       ASM_OUTPUT_SKIP (asm_out_file, HOST_WIDE_INT_1U);
7795       break;
7796 
7797     case SWITCH_TYPE_DESCRIPTIVE:
7798       if (name == NULL)
7799 	{
7800 	  /* Distinguish between invocations where name is NULL.  */
7801 	  static bool started = false;
7802 
7803 	  if (!started)
7804 	    {
7805 	      section * sec;
7806 
7807 	      sec = get_section (targetm.asm_out.record_gcc_switches_section,
7808 				 SECTION_DEBUG
7809 				 | SECTION_MERGE
7810 				 | SECTION_STRINGS
7811 				 | (SECTION_ENTSIZE & 1),
7812 				 NULL);
7813 	      switch_to_section (sec);
7814 	      started = true;
7815 	    }
7816 	}
7817 
7818     default:
7819       break;
7820     }
7821 
7822   /* The return value is currently ignored by the caller, but must be 0.
7823      For -fverbose-asm the return value would be the number of characters
7824      emitted into the assembler file.  */
7825   return 0;
7826 }
7827 
7828 /* Emit text to declare externally defined symbols. It is needed to
7829    properly support non-default visibility.  */
7830 void
default_elf_asm_output_external(FILE * file ATTRIBUTE_UNUSED,tree decl,const char * name ATTRIBUTE_UNUSED)7831 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7832 				 tree decl,
7833 				 const char *name ATTRIBUTE_UNUSED)
7834 {
7835   /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7836      set in order to avoid putting out names that are never really
7837      used.  Always output visibility specified in the source.  */
7838   if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7839       && (DECL_VISIBILITY_SPECIFIED (decl)
7840 	  || targetm.binds_local_p (decl)))
7841     maybe_assemble_visibility (decl);
7842 }
7843 
7844 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME.  */
7845 
7846 void
default_asm_output_source_filename(FILE * file,const char * name)7847 default_asm_output_source_filename (FILE *file, const char *name)
7848 {
7849 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7850   ASM_OUTPUT_SOURCE_FILENAME (file, name);
7851 #else
7852   fprintf (file, "\t.file\t");
7853   output_quoted_string (file, name);
7854   putc ('\n', file);
7855 #endif
7856 }
7857 
7858 /* Output a file name in the form wanted by System V.  */
7859 
7860 void
output_file_directive(FILE * asm_file,const char * input_name)7861 output_file_directive (FILE *asm_file, const char *input_name)
7862 {
7863   int len;
7864   const char *na;
7865 
7866   if (input_name == NULL)
7867     input_name = "<stdin>";
7868   else
7869     input_name = remap_debug_filename (input_name);
7870 
7871   len = strlen (input_name);
7872   na = input_name + len;
7873 
7874   /* NA gets INPUT_NAME sans directory names.  */
7875   while (na > input_name)
7876     {
7877       if (IS_DIR_SEPARATOR (na[-1]))
7878 	break;
7879       na--;
7880     }
7881 
7882   targetm.asm_out.output_source_filename (asm_file, na);
7883 }
7884 
7885 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7886    EXP.  */
7887 rtx
make_debug_expr_from_rtl(const_rtx exp)7888 make_debug_expr_from_rtl (const_rtx exp)
7889 {
7890   tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7891   machine_mode mode = GET_MODE (exp);
7892   rtx dval;
7893 
7894   DECL_ARTIFICIAL (ddecl) = 1;
7895   if (REG_P (exp) && REG_EXPR (exp))
7896     type = TREE_TYPE (REG_EXPR (exp));
7897   else if (MEM_P (exp) && MEM_EXPR (exp))
7898     type = TREE_TYPE (MEM_EXPR (exp));
7899   else
7900     type = NULL_TREE;
7901   if (type && TYPE_MODE (type) == mode)
7902     TREE_TYPE (ddecl) = type;
7903   else
7904     TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7905   SET_DECL_MODE (ddecl, mode);
7906   dval = gen_rtx_DEBUG_EXPR (mode);
7907   DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7908   SET_DECL_RTL (ddecl, dval);
7909   return dval;
7910 }
7911 
7912 #ifdef ELF_ASCII_ESCAPES
7913 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets.  */
7914 
7915 void
default_elf_asm_output_limited_string(FILE * f,const char * s)7916 default_elf_asm_output_limited_string (FILE *f, const char *s)
7917 {
7918   int escape;
7919   unsigned char c;
7920 
7921   fputs (STRING_ASM_OP, f);
7922   putc ('"', f);
7923   while (*s != '\0')
7924     {
7925       c = *s;
7926       escape = ELF_ASCII_ESCAPES[c];
7927       switch (escape)
7928 	{
7929 	case 0:
7930 	  putc (c, f);
7931 	  break;
7932 	case 1:
7933 	  putc ('\\', f);
7934 	  putc ('0'+((c>>6)&7), f);
7935 	  putc ('0'+((c>>3)&7), f);
7936 	  putc ('0'+(c&7), f);
7937 	  break;
7938 	default:
7939 	  putc ('\\', f);
7940 	  putc (escape, f);
7941 	  break;
7942 	}
7943       s++;
7944     }
7945   putc ('\"', f);
7946   putc ('\n', f);
7947 }
7948 
7949 /* Default ASM_OUTPUT_ASCII for ELF targets.  */
7950 
7951 void
default_elf_asm_output_ascii(FILE * f,const char * s,unsigned int len)7952 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7953 {
7954   const char *limit = s + len;
7955   const char *last_null = NULL;
7956   unsigned bytes_in_chunk = 0;
7957   unsigned char c;
7958   int escape;
7959 
7960   for (; s < limit; s++)
7961     {
7962       const char *p;
7963 
7964       if (bytes_in_chunk >= 60)
7965 	{
7966 	  putc ('\"', f);
7967 	  putc ('\n', f);
7968 	  bytes_in_chunk = 0;
7969 	}
7970 
7971       if (s > last_null)
7972 	{
7973 	  for (p = s; p < limit && *p != '\0'; p++)
7974 	    continue;
7975 	  last_null = p;
7976 	}
7977       else
7978 	p = last_null;
7979 
7980       if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7981 	{
7982 	  if (bytes_in_chunk > 0)
7983 	    {
7984 	      putc ('\"', f);
7985 	      putc ('\n', f);
7986 	      bytes_in_chunk = 0;
7987 	    }
7988 
7989 	  default_elf_asm_output_limited_string (f, s);
7990 	  s = p;
7991 	}
7992       else
7993 	{
7994 	  if (bytes_in_chunk == 0)
7995 	    fputs (ASCII_DATA_ASM_OP "\"", f);
7996 
7997 	  c = *s;
7998 	  escape = ELF_ASCII_ESCAPES[c];
7999 	  switch (escape)
8000 	    {
8001 	    case 0:
8002 	      putc (c, f);
8003 	      bytes_in_chunk++;
8004 	      break;
8005 	    case 1:
8006 	      putc ('\\', f);
8007 	      putc ('0'+((c>>6)&7), f);
8008 	      putc ('0'+((c>>3)&7), f);
8009 	      putc ('0'+(c&7), f);
8010 	      bytes_in_chunk += 4;
8011 	      break;
8012 	    default:
8013 	      putc ('\\', f);
8014 	      putc (escape, f);
8015 	      bytes_in_chunk += 2;
8016 	      break;
8017 	    }
8018 
8019 	}
8020     }
8021 
8022   if (bytes_in_chunk > 0)
8023     {
8024       putc ('\"', f);
8025       putc ('\n', f);
8026     }
8027 }
8028 #endif
8029 
8030 static GTY(()) section *elf_init_array_section;
8031 static GTY(()) section *elf_fini_array_section;
8032 
8033 static section *
get_elf_initfini_array_priority_section(int priority,bool constructor_p)8034 get_elf_initfini_array_priority_section (int priority,
8035 					 bool constructor_p)
8036 {
8037   section *sec;
8038   if (priority != DEFAULT_INIT_PRIORITY)
8039     {
8040       char buf[18];
8041       sprintf (buf, "%s.%.5u",
8042 	       constructor_p ? ".init_array" : ".fini_array",
8043 	       priority);
8044       sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
8045     }
8046   else
8047     {
8048       if (constructor_p)
8049 	{
8050 	  if (elf_init_array_section == NULL)
8051 	    elf_init_array_section
8052 	      = get_section (".init_array",
8053 			     SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
8054 	  sec = elf_init_array_section;
8055 	}
8056       else
8057 	{
8058 	  if (elf_fini_array_section == NULL)
8059 	    elf_fini_array_section
8060 	      = get_section (".fini_array",
8061 			     SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
8062 	  sec = elf_fini_array_section;
8063 	}
8064     }
8065   return sec;
8066 }
8067 
8068 /* Use .init_array section for constructors. */
8069 
8070 void
default_elf_init_array_asm_out_constructor(rtx symbol,int priority)8071 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
8072 {
8073   section *sec = get_elf_initfini_array_priority_section (priority,
8074 							  true);
8075   assemble_addr_to_section (symbol, sec);
8076 }
8077 
8078 /* Use .fini_array section for destructors. */
8079 
8080 void
default_elf_fini_array_asm_out_destructor(rtx symbol,int priority)8081 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
8082 {
8083   section *sec = get_elf_initfini_array_priority_section (priority,
8084 							  false);
8085   assemble_addr_to_section (symbol, sec);
8086 }
8087 
8088 /* Default TARGET_ASM_OUTPUT_IDENT hook.
8089 
8090    This is a bit of a cheat.  The real default is a no-op, but this
8091    hook is the default for all targets with a .ident directive.  */
8092 
8093 void
default_asm_output_ident_directive(const char * ident_str)8094 default_asm_output_ident_directive (const char *ident_str)
8095 {
8096   const char *ident_asm_op = "\t.ident\t";
8097 
8098   /* If we are still in the front end, do not write out the string
8099      to asm_out_file.  Instead, add a fake top-level asm statement.
8100      This allows the front ends to use this hook without actually
8101      writing to asm_out_file, to handle #ident or Pragma Ident.  */
8102   if (symtab->state == PARSING)
8103     {
8104       char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
8105       symtab->finalize_toplevel_asm (build_string (strlen (buf), buf));
8106     }
8107   else
8108     fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
8109 }
8110 
8111 
8112 /* This function ensures that vtable_map variables are not only
8113    in the comdat section, but that each variable has its own unique
8114    comdat name.  Without this the variables end up in the same section
8115    with a single comdat name.
8116 
8117    FIXME:  resolve_unique_section needs to deal better with
8118    decls with both DECL_SECTION_NAME and DECL_ONE_ONLY.  Once
8119    that is fixed, this if-else statement can be replaced with
8120    a single call to "switch_to_section (sect)".  */
8121 
8122 static void
handle_vtv_comdat_section(section * sect,const_tree decl ATTRIBUTE_UNUSED)8123 handle_vtv_comdat_section (section *sect, const_tree decl ATTRIBUTE_UNUSED)
8124 {
8125 #if defined (OBJECT_FORMAT_ELF)
8126   targetm.asm_out.named_section (sect->named.name,
8127 				 sect->named.common.flags
8128 				 | SECTION_LINKONCE,
8129 				 DECL_NAME (decl));
8130   in_section = sect;
8131 #else
8132   /* Neither OBJECT_FORMAT_PE, nor OBJECT_FORMAT_COFF is set here.
8133      Therefore the following check is used.
8134      In case a the target is PE or COFF a comdat group section
8135      is created, e.g. .vtable_map_vars$foo. The linker places
8136      everything in .vtable_map_vars at the end.
8137 
8138      A fix could be made in
8139      gcc/config/i386/winnt.c: i386_pe_unique_section.  */
8140   if (TARGET_PECOFF)
8141     {
8142       char *name;
8143 
8144       if (TREE_CODE (DECL_NAME (decl)) == IDENTIFIER_NODE)
8145 	name = ACONCAT ((sect->named.name, "$",
8146 			 IDENTIFIER_POINTER (DECL_NAME (decl)), NULL));
8147       else
8148 	name = ACONCAT ((sect->named.name, "$",
8149 			 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (DECL_NAME (decl))),
8150 			 NULL));
8151 
8152       targetm.asm_out.named_section (name,
8153 				     sect->named.common.flags
8154 				     | SECTION_LINKONCE,
8155 				     DECL_NAME (decl));
8156       in_section = sect;
8157     }
8158   else
8159     switch_to_section (sect);
8160 #endif
8161 }
8162 
8163 #include "gt-varasm.h"
8164