1 /* Output variables, constants and external declarations, for GNU compiler.
2    Copyright (C) 1987-2018 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);
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.  */
367 
368 static struct object_block *
get_block_for_section(section * sect)369 get_block_for_section (section *sect)
370 {
371   struct object_block *block;
372 
373   if (sect == NULL)
374     return NULL;
375 
376   object_block **slot
377     = object_block_htab->find_slot_with_hash (sect, hash_section (sect),
378 					      INSERT);
379   block = *slot;
380   if (block == NULL)
381     {
382       block = ggc_cleared_alloc<object_block> ();
383       block->sect = sect;
384       *slot = block;
385     }
386   return block;
387 }
388 
389 /* Create a symbol with label LABEL and place it at byte offset
390    OFFSET in BLOCK.  OFFSET can be negative if the symbol's offset
391    is not yet known.  LABEL must be a garbage-collected string.  */
392 
393 static rtx
create_block_symbol(const char * label,struct object_block * block,HOST_WIDE_INT offset)394 create_block_symbol (const char *label, struct object_block *block,
395 		     HOST_WIDE_INT offset)
396 {
397   rtx symbol;
398   unsigned int size;
399 
400   /* Create the extended SYMBOL_REF.  */
401   size = RTX_HDR_SIZE + sizeof (struct block_symbol);
402   symbol = (rtx) ggc_internal_alloc (size);
403 
404   /* Initialize the normal SYMBOL_REF fields.  */
405   memset (symbol, 0, size);
406   PUT_CODE (symbol, SYMBOL_REF);
407   PUT_MODE (symbol, Pmode);
408   XSTR (symbol, 0) = label;
409   SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_HAS_BLOCK_INFO;
410 
411   /* Initialize the block_symbol stuff.  */
412   SYMBOL_REF_BLOCK (symbol) = block;
413   SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
414 
415   return symbol;
416 }
417 
418 /* Return a section with a particular name and with whatever SECTION_*
419    flags section_type_flags deems appropriate.  The name of the section
420    is taken from NAME if nonnull, otherwise it is taken from DECL's
421    DECL_SECTION_NAME.  DECL is the decl associated with the section
422    (see the section comment for details) and RELOC is as for
423    section_type_flags.  */
424 
425 section *
get_named_section(tree decl,const char * name,int reloc)426 get_named_section (tree decl, const char *name, int reloc)
427 {
428   unsigned int flags;
429 
430   if (name == NULL)
431     {
432       gcc_assert (decl && DECL_P (decl) && DECL_SECTION_NAME (decl));
433       name = DECL_SECTION_NAME (decl);
434     }
435 
436   flags = targetm.section_type_flags (decl, name, reloc);
437   return get_section (name, flags, decl);
438 }
439 
440 /* Worker for resolve_unique_section.  */
441 
442 static bool
set_implicit_section(struct symtab_node * n,void * data ATTRIBUTE_UNUSED)443 set_implicit_section (struct symtab_node *n, void *data ATTRIBUTE_UNUSED)
444 {
445   n->implicit_section = true;
446   return false;
447 }
448 
449 /* If required, set DECL_SECTION_NAME to a unique name.  */
450 
451 void
resolve_unique_section(tree decl,int reloc ATTRIBUTE_UNUSED,int flag_function_or_data_sections)452 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
453 			int flag_function_or_data_sections)
454 {
455   if (DECL_SECTION_NAME (decl) == NULL
456       && targetm_common.have_named_sections
457       && (flag_function_or_data_sections
458 	  || DECL_COMDAT_GROUP (decl)))
459     {
460       targetm.asm_out.unique_section (decl, reloc);
461       if (DECL_SECTION_NAME (decl))
462 	symtab_node::get (decl)->call_for_symbol_and_aliases
463 	  (set_implicit_section, NULL, true);
464     }
465 }
466 
467 #ifdef BSS_SECTION_ASM_OP
468 
469 #ifdef ASM_OUTPUT_ALIGNED_BSS
470 
471 /* Utility function for targets to use in implementing
472    ASM_OUTPUT_ALIGNED_BSS.
473    ??? It is believed that this function will work in most cases so such
474    support is localized here.  */
475 
476 static void
asm_output_aligned_bss(FILE * file,tree decl ATTRIBUTE_UNUSED,const char * name,unsigned HOST_WIDE_INT size,int align)477 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
478 			const char *name, unsigned HOST_WIDE_INT size,
479 			int align)
480 {
481   switch_to_section (bss_section);
482   ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
483 #ifdef ASM_DECLARE_OBJECT_NAME
484   last_assemble_variable_decl = decl;
485   ASM_DECLARE_OBJECT_NAME (file, name, decl);
486 #else
487   /* Standard thing is just output label for the object.  */
488   ASM_OUTPUT_LABEL (file, name);
489 #endif /* ASM_DECLARE_OBJECT_NAME */
490   ASM_OUTPUT_SKIP (file, size ? size : 1);
491 }
492 
493 #endif
494 
495 #endif /* BSS_SECTION_ASM_OP */
496 
497 #ifndef USE_SELECT_SECTION_FOR_FUNCTIONS
498 /* Return the hot section for function DECL.  Return text_section for
499    null DECLs.  */
500 
501 static section *
hot_function_section(tree decl)502 hot_function_section (tree decl)
503 {
504   if (decl != NULL_TREE
505       && DECL_SECTION_NAME (decl) != NULL
506       && targetm_common.have_named_sections)
507     return get_named_section (decl, NULL, 0);
508   else
509     return text_section;
510 }
511 #endif
512 
513 /* Return section for TEXT_SECTION_NAME if DECL or DECL_SECTION_NAME (DECL)
514    is NULL.
515 
516    When DECL_SECTION_NAME is non-NULL and it is implicit section and
517    NAMED_SECTION_SUFFIX is non-NULL, then produce section called
518    concatenate the name with NAMED_SECTION_SUFFIX.
519    Otherwise produce "TEXT_SECTION_NAME.IMPLICIT_NAME".  */
520 
521 section *
get_named_text_section(tree decl,const char * text_section_name,const char * named_section_suffix)522 get_named_text_section (tree decl,
523 		        const char *text_section_name,
524 		        const char *named_section_suffix)
525 {
526   if (decl && DECL_SECTION_NAME (decl))
527     {
528       if (named_section_suffix)
529 	{
530 	  const char *dsn = DECL_SECTION_NAME (decl);
531 	  const char *stripped_name;
532 	  char *name, *buffer;
533 
534 	  name = (char *) alloca (strlen (dsn) + 1);
535 	  memcpy (name, dsn,
536 		  strlen (dsn) + 1);
537 
538 	  stripped_name = targetm.strip_name_encoding (name);
539 
540 	  buffer = ACONCAT ((stripped_name, named_section_suffix, NULL));
541 	  return get_named_section (decl, buffer, 0);
542 	}
543       else if (symtab_node::get (decl)->implicit_section)
544 	{
545 	  const char *name;
546 
547 	  /* Do not try to split gnu_linkonce functions.  This gets somewhat
548 	     slipperly.  */
549 	  if (DECL_COMDAT_GROUP (decl) && !HAVE_COMDAT_GROUP)
550 	    return NULL;
551 	  name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
552 	  name = targetm.strip_name_encoding (name);
553 	  return get_named_section (decl, ACONCAT ((text_section_name, ".",
554 				                   name, NULL)), 0);
555 	}
556       else
557 	return NULL;
558     }
559   return get_named_section (decl, text_section_name, 0);
560 }
561 
562 /* Choose named function section based on its frequency.  */
563 
564 section *
default_function_section(tree decl,enum node_frequency freq,bool startup,bool exit)565 default_function_section (tree decl, enum node_frequency freq,
566 			  bool startup, bool exit)
567 {
568 #if defined HAVE_LD_EH_GC_SECTIONS && defined HAVE_LD_EH_GC_SECTIONS_BUG
569   /* Old GNU linkers have buggy --gc-section support, which sometimes
570      results in .gcc_except_table* sections being garbage collected.  */
571   if (decl
572       && symtab_node::get (decl)->implicit_section)
573     return NULL;
574 #endif
575 
576   if (!flag_reorder_functions
577       || !targetm_common.have_named_sections)
578     return NULL;
579   /* Startup code should go to startup subsection unless it is
580      unlikely executed (this happens especially with function splitting
581      where we can split away unnecessary parts of static constructors.  */
582   if (startup && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
583   {
584     /* If we do have a profile or(and) LTO phase is executed, we do not need
585        these ELF section.  */
586     if (!in_lto_p || !flag_profile_values)
587       return get_named_text_section (decl, ".text.startup", NULL);
588     else
589       return NULL;
590   }
591 
592   /* Similarly for exit.  */
593   if (exit && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
594     return get_named_text_section (decl, ".text.exit", NULL);
595 
596   /* Group cold functions together, similarly for hot code.  */
597   switch (freq)
598     {
599       case NODE_FREQUENCY_UNLIKELY_EXECUTED:
600 	return get_named_text_section (decl, ".text.unlikely", NULL);
601       case NODE_FREQUENCY_HOT:
602         /* If we do have a profile or(and) LTO phase is executed, we do not need
603            these ELF section.  */
604         if (!in_lto_p || !flag_profile_values)
605           return get_named_text_section (decl, ".text.hot", NULL);
606 	/* FALLTHRU */
607       default:
608 	return NULL;
609     }
610 }
611 
612 /* Return the section for function DECL.
613 
614    If DECL is NULL_TREE, return the text section.  We can be passed
615    NULL_TREE under some circumstances by dbxout.c at least.
616 
617    If FORCE_COLD is true, return cold function section ignoring
618    the frequency info of cgraph_node.  */
619 
620 static section *
function_section_1(tree decl,bool force_cold)621 function_section_1 (tree decl, bool force_cold)
622 {
623   section *section = NULL;
624   enum node_frequency freq = NODE_FREQUENCY_NORMAL;
625   bool startup = false, exit = false;
626 
627   if (decl)
628     {
629       struct cgraph_node *node = cgraph_node::get (decl);
630 
631       if (node)
632 	{
633 	  freq = node->frequency;
634 	  startup = node->only_called_at_startup;
635 	  exit = node->only_called_at_exit;
636 	}
637     }
638   if (force_cold)
639     freq = NODE_FREQUENCY_UNLIKELY_EXECUTED;
640 
641 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
642   if (decl != NULL_TREE
643       && DECL_SECTION_NAME (decl) != NULL)
644     {
645       if (targetm.asm_out.function_section)
646 	section = targetm.asm_out.function_section (decl, freq,
647 						    startup, exit);
648       if (section)
649 	return section;
650       return get_named_section (decl, NULL, 0);
651     }
652   else
653     return targetm.asm_out.select_section
654 	    (decl, freq == NODE_FREQUENCY_UNLIKELY_EXECUTED,
655 	     symtab_node::get (decl)->definition_alignment ());
656 #else
657   if (targetm.asm_out.function_section)
658     section = targetm.asm_out.function_section (decl, freq, startup, exit);
659   if (section)
660     return section;
661   return hot_function_section (decl);
662 #endif
663 }
664 
665 /* Return the section for function DECL.
666 
667    If DECL is NULL_TREE, return the text section.  We can be passed
668    NULL_TREE under some circumstances by dbxout.c at least.  */
669 
670 section *
function_section(tree decl)671 function_section (tree decl)
672 {
673   /* Handle cases where function splitting code decides
674      to put function entry point into unlikely executed section
675      despite the fact that the function itself is not cold
676      (i.e. it is called rarely but contains a hot loop that is
677      better to live in hot subsection for the code locality).  */
678   return function_section_1 (decl,
679 			     first_function_block_is_cold);
680 }
681 
682 /* Return the section for the current function, take IN_COLD_SECTION_P
683    into account.  */
684 
685 section *
current_function_section(void)686 current_function_section (void)
687 {
688   return function_section_1 (current_function_decl, in_cold_section_p);
689 }
690 
691 /* Tell assembler to switch to unlikely-to-be-executed text section.  */
692 
693 section *
unlikely_text_section(void)694 unlikely_text_section (void)
695 {
696   return function_section_1 (current_function_decl, true);
697 }
698 
699 /* When called within a function context, return true if the function
700    has been assigned a cold text section and if SECT is that section.
701    When called outside a function context, return true if SECT is the
702    default cold section.  */
703 
704 bool
unlikely_text_section_p(section * sect)705 unlikely_text_section_p (section *sect)
706 {
707   return sect == function_section_1 (current_function_decl, true);
708 }
709 
710 /* Switch to the other function partition (if inside of hot section
711    into cold section, otherwise into the hot section).  */
712 
713 void
switch_to_other_text_partition(void)714 switch_to_other_text_partition (void)
715 {
716   in_cold_section_p = !in_cold_section_p;
717   switch_to_section (current_function_section ());
718 }
719 
720 /* Return the read-only data section associated with function DECL.  */
721 
722 section *
default_function_rodata_section(tree decl)723 default_function_rodata_section (tree decl)
724 {
725   if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
726     {
727       const char *name = DECL_SECTION_NAME (decl);
728 
729       if (DECL_COMDAT_GROUP (decl) && HAVE_COMDAT_GROUP)
730         {
731 	  const char *dot;
732 	  size_t len;
733 	  char* rname;
734 
735 	  dot = strchr (name + 1, '.');
736 	  if (!dot)
737 	    dot = name;
738 	  len = strlen (dot) + 8;
739 	  rname = (char *) alloca (len);
740 
741 	  strcpy (rname, ".rodata");
742 	  strcat (rname, dot);
743 	  return get_section (rname, SECTION_LINKONCE, decl);
744 	}
745       /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo.  */
746       else if (DECL_COMDAT_GROUP (decl)
747 	       && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
748 	{
749 	  size_t len = strlen (name) + 1;
750 	  char *rname = (char *) alloca (len);
751 
752 	  memcpy (rname, name, len);
753 	  rname[14] = 'r';
754 	  return get_section (rname, SECTION_LINKONCE, decl);
755 	}
756       /* For .text.foo we want to use .rodata.foo.  */
757       else if (flag_function_sections && flag_data_sections
758 	       && strncmp (name, ".text.", 6) == 0)
759 	{
760 	  size_t len = strlen (name) + 1;
761 	  char *rname = (char *) alloca (len + 2);
762 
763 	  memcpy (rname, ".rodata", 7);
764 	  memcpy (rname + 7, name + 5, len - 5);
765 	  return get_section (rname, 0, decl);
766 	}
767     }
768 
769   return readonly_data_section;
770 }
771 
772 /* Return the read-only data section associated with function DECL
773    for targets where that section should be always the single
774    readonly data section.  */
775 
776 section *
default_no_function_rodata_section(tree decl ATTRIBUTE_UNUSED)777 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
778 {
779   return readonly_data_section;
780 }
781 
782 /* A subroutine of mergeable_string_section and mergeable_constant_section.  */
783 
784 static const char *
function_mergeable_rodata_prefix(void)785 function_mergeable_rodata_prefix (void)
786 {
787   section *s = targetm.asm_out.function_rodata_section (current_function_decl);
788   if (SECTION_STYLE (s) == SECTION_NAMED)
789     return s->named.name;
790   else
791     return targetm.asm_out.mergeable_rodata_prefix;
792 }
793 
794 /* Return the section to use for string merging.  */
795 
796 static section *
mergeable_string_section(tree decl ATTRIBUTE_UNUSED,unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,unsigned int flags ATTRIBUTE_UNUSED)797 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
798 			  unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
799 			  unsigned int flags ATTRIBUTE_UNUSED)
800 {
801   HOST_WIDE_INT len;
802 
803   if (HAVE_GAS_SHF_MERGE && flag_merge_constants
804       && TREE_CODE (decl) == STRING_CST
805       && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
806       && align <= 256
807       && (len = int_size_in_bytes (TREE_TYPE (decl))) > 0
808       && TREE_STRING_LENGTH (decl) >= len)
809     {
810       scalar_int_mode mode;
811       unsigned int modesize;
812       const char *str;
813       HOST_WIDE_INT i;
814       int j, unit;
815       const char *prefix = function_mergeable_rodata_prefix ();
816       char *name = (char *) alloca (strlen (prefix) + 30);
817 
818       mode = SCALAR_INT_TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
819       modesize = GET_MODE_BITSIZE (mode);
820       if (modesize >= 8 && modesize <= 256
821 	  && (modesize & (modesize - 1)) == 0)
822 	{
823 	  if (align < modesize)
824 	    align = modesize;
825 
826 	  str = TREE_STRING_POINTER (decl);
827 	  unit = GET_MODE_SIZE (mode);
828 
829 	  /* Check for embedded NUL characters.  */
830 	  for (i = 0; i < len; i += unit)
831 	    {
832 	      for (j = 0; j < unit; j++)
833 		if (str[i + j] != '\0')
834 		  break;
835 	      if (j == unit)
836 		break;
837 	    }
838 	  if (i == len - unit)
839 	    {
840 	      sprintf (name, "%s.str%d.%d", prefix,
841 		       modesize / 8, (int) (align / 8));
842 	      flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
843 	      return get_section (name, flags, NULL);
844 	    }
845 	}
846     }
847 
848   return readonly_data_section;
849 }
850 
851 /* Return the section to use for constant merging.  */
852 
853 section *
mergeable_constant_section(machine_mode mode ATTRIBUTE_UNUSED,unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,unsigned int flags ATTRIBUTE_UNUSED)854 mergeable_constant_section (machine_mode mode ATTRIBUTE_UNUSED,
855 			    unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
856 			    unsigned int flags ATTRIBUTE_UNUSED)
857 {
858   if (HAVE_GAS_SHF_MERGE && flag_merge_constants
859       && mode != VOIDmode
860       && mode != BLKmode
861       && known_le (GET_MODE_BITSIZE (mode), align)
862       && align >= 8
863       && align <= 256
864       && (align & (align - 1)) == 0)
865     {
866       const char *prefix = function_mergeable_rodata_prefix ();
867       char *name = (char *) alloca (strlen (prefix) + 30);
868 
869       sprintf (name, "%s.cst%d", prefix, (int) (align / 8));
870       flags |= (align / 8) | SECTION_MERGE;
871       return get_section (name, flags, NULL);
872     }
873   return readonly_data_section;
874 }
875 
876 /* Given NAME, a putative register name, discard any customary prefixes.  */
877 
878 static const char *
strip_reg_name(const char * name)879 strip_reg_name (const char *name)
880 {
881 #ifdef REGISTER_PREFIX
882   if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
883     name += strlen (REGISTER_PREFIX);
884 #endif
885   if (name[0] == '%' || name[0] == '#')
886     name++;
887   return name;
888 }
889 
890 /* The user has asked for a DECL to have a particular name.  Set (or
891    change) it in such a way that we don't prefix an underscore to
892    it.  */
893 void
set_user_assembler_name(tree decl,const char * name)894 set_user_assembler_name (tree decl, const char *name)
895 {
896   char *starred = (char *) alloca (strlen (name) + 2);
897   starred[0] = '*';
898   strcpy (starred + 1, name);
899   symtab->change_decl_assembler_name (decl, get_identifier (starred));
900   SET_DECL_RTL (decl, NULL_RTX);
901 }
902 
903 /* Decode an `asm' spec for a declaration as a register name.
904    Return the register number, or -1 if nothing specified,
905    or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
906    or -3 if ASMSPEC is `cc' and is not recognized,
907    or -4 if ASMSPEC is `memory' and is not recognized.
908    Accept an exact spelling or a decimal number.
909    Prefixes such as % are optional.  */
910 
911 int
decode_reg_name_and_count(const char * asmspec,int * pnregs)912 decode_reg_name_and_count (const char *asmspec, int *pnregs)
913 {
914   /* Presume just one register is clobbered.  */
915   *pnregs = 1;
916 
917   if (asmspec != 0)
918     {
919       int i;
920 
921       /* Get rid of confusing prefixes.  */
922       asmspec = strip_reg_name (asmspec);
923 
924       /* Allow a decimal number as a "register name".  */
925       for (i = strlen (asmspec) - 1; i >= 0; i--)
926 	if (! ISDIGIT (asmspec[i]))
927 	  break;
928       if (asmspec[0] != 0 && i < 0)
929 	{
930 	  i = atoi (asmspec);
931 	  if (i < FIRST_PSEUDO_REGISTER && i >= 0 && reg_names[i][0])
932 	    return i;
933 	  else
934 	    return -2;
935 	}
936 
937       for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
938 	if (reg_names[i][0]
939 	    && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
940 	  return i;
941 
942 #ifdef OVERLAPPING_REGISTER_NAMES
943       {
944 	static const struct
945 	{
946 	  const char *const name;
947 	  const int number;
948 	  const int nregs;
949 	} table[] = OVERLAPPING_REGISTER_NAMES;
950 
951 	for (i = 0; i < (int) ARRAY_SIZE (table); i++)
952 	  if (table[i].name[0]
953 	      && ! strcmp (asmspec, table[i].name))
954 	    {
955 	      *pnregs = table[i].nregs;
956 	      return table[i].number;
957 	    }
958       }
959 #endif /* OVERLAPPING_REGISTER_NAMES */
960 
961 #ifdef ADDITIONAL_REGISTER_NAMES
962       {
963 	static const struct { const char *const name; const int number; } table[]
964 	  = ADDITIONAL_REGISTER_NAMES;
965 
966 	for (i = 0; i < (int) ARRAY_SIZE (table); i++)
967 	  if (table[i].name[0]
968 	      && ! strcmp (asmspec, table[i].name)
969 	      && reg_names[table[i].number][0])
970 	    return table[i].number;
971       }
972 #endif /* ADDITIONAL_REGISTER_NAMES */
973 
974       if (!strcmp (asmspec, "memory"))
975 	return -4;
976 
977       if (!strcmp (asmspec, "cc"))
978 	return -3;
979 
980       return -2;
981     }
982 
983   return -1;
984 }
985 
986 int
decode_reg_name(const char * name)987 decode_reg_name (const char *name)
988 {
989   int count;
990   return decode_reg_name_and_count (name, &count);
991 }
992 
993 
994 /* Return true if DECL's initializer is suitable for a BSS section.  */
995 
996 bool
bss_initializer_p(const_tree decl,bool named)997 bss_initializer_p (const_tree decl, bool named)
998 {
999   /* Do not put non-common constants into the .bss section, they belong in
1000      a readonly section, except when NAMED is true.  */
1001   return ((!TREE_READONLY (decl) || DECL_COMMON (decl) || named)
1002 	  && (DECL_INITIAL (decl) == NULL
1003 	      /* In LTO we have no errors in program; error_mark_node is used
1004 	         to mark offlined constructors.  */
1005 	      || (DECL_INITIAL (decl) == error_mark_node
1006 	          && !in_lto_p)
1007 	      || (flag_zero_initialized_in_bss
1008 	          && initializer_zerop (DECL_INITIAL (decl)))));
1009 }
1010 
1011 /* Compute the alignment of variable specified by DECL.
1012    DONT_OUTPUT_DATA is from assemble_variable.  */
1013 
1014 void
align_variable(tree decl,bool dont_output_data)1015 align_variable (tree decl, bool dont_output_data)
1016 {
1017   unsigned int align = DECL_ALIGN (decl);
1018 
1019   /* In the case for initialing an array whose length isn't specified,
1020      where we have not yet been able to do the layout,
1021      figure out the proper alignment now.  */
1022   if (dont_output_data && DECL_SIZE (decl) == 0
1023       && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
1024     align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
1025 
1026   /* Some object file formats have a maximum alignment which they support.
1027      In particular, a.out format supports a maximum alignment of 4.  */
1028   if (align > MAX_OFILE_ALIGNMENT)
1029     {
1030       error ("alignment of %q+D is greater than maximum object "
1031 	     "file alignment %d", decl,
1032 	     MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
1033       align = MAX_OFILE_ALIGNMENT;
1034     }
1035 
1036   if (! DECL_USER_ALIGN (decl))
1037     {
1038 #ifdef DATA_ABI_ALIGNMENT
1039       unsigned int data_abi_align
1040 	= DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1041       /* For backwards compatibility, don't assume the ABI alignment for
1042 	 TLS variables.  */
1043       if (! DECL_THREAD_LOCAL_P (decl) || data_abi_align <= BITS_PER_WORD)
1044 	align = data_abi_align;
1045 #endif
1046 
1047       /* On some machines, it is good to increase alignment sometimes.
1048 	 But as DECL_ALIGN is used both for actually emitting the variable
1049 	 and for code accessing the variable as guaranteed alignment, we
1050 	 can only increase the alignment if it is a performance optimization
1051 	 if the references to it must bind to the current definition.  */
1052       if (decl_binds_to_current_def_p (decl)
1053 	  && !DECL_VIRTUAL_P (decl))
1054 	{
1055 #ifdef DATA_ALIGNMENT
1056 	  unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1057 	  /* Don't increase alignment too much for TLS variables - TLS space
1058 	     is too precious.  */
1059 	  if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1060 	    align = data_align;
1061 #endif
1062 	  if (DECL_INITIAL (decl) != 0
1063 	      /* In LTO we have no errors in program; error_mark_node is used
1064 		 to mark offlined constructors.  */
1065 	      && (in_lto_p || DECL_INITIAL (decl) != error_mark_node))
1066 	    {
1067 	      unsigned int const_align
1068 		= targetm.constant_alignment (DECL_INITIAL (decl), align);
1069 	      /* Don't increase alignment too much for TLS variables - TLS
1070 		 space is too precious.  */
1071 	      if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1072 		align = const_align;
1073 	    }
1074 	}
1075     }
1076 
1077   /* Reset the alignment in case we have made it tighter, so we can benefit
1078      from it in get_pointer_alignment.  */
1079   SET_DECL_ALIGN (decl, align);
1080 }
1081 
1082 /* Return DECL_ALIGN (decl), possibly increased for optimization purposes
1083    beyond what align_variable returned.  */
1084 
1085 static unsigned int
get_variable_align(tree decl)1086 get_variable_align (tree decl)
1087 {
1088   unsigned int align = DECL_ALIGN (decl);
1089 
1090   /* For user aligned vars or static vars align_variable already did
1091      everything.  */
1092   if (DECL_USER_ALIGN (decl) || !TREE_PUBLIC (decl))
1093     return align;
1094 
1095 #ifdef DATA_ABI_ALIGNMENT
1096   if (DECL_THREAD_LOCAL_P (decl))
1097     align = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1098 #endif
1099 
1100   /* For decls that bind to the current definition, align_variable
1101      did also everything, except for not assuming ABI required alignment
1102      of TLS variables.  For other vars, increase the alignment here
1103      as an optimization.  */
1104   if (!decl_binds_to_current_def_p (decl))
1105     {
1106       /* On some machines, it is good to increase alignment sometimes.  */
1107 #ifdef DATA_ALIGNMENT
1108       unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1109       /* Don't increase alignment too much for TLS variables - TLS space
1110          is too precious.  */
1111       if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1112 	align = data_align;
1113 #endif
1114       if (DECL_INITIAL (decl) != 0
1115 	  /* In LTO we have no errors in program; error_mark_node is used
1116 	     to mark offlined constructors.  */
1117 	  && (in_lto_p || DECL_INITIAL (decl) != error_mark_node))
1118 	{
1119 	  unsigned int const_align
1120 	    = targetm.constant_alignment (DECL_INITIAL (decl), align);
1121 	  /* Don't increase alignment too much for TLS variables - TLS space
1122 	     is too precious.  */
1123 	  if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1124 	    align = const_align;
1125 	}
1126     }
1127 
1128   return align;
1129 }
1130 
1131 /* Return the section into which the given VAR_DECL or CONST_DECL
1132    should be placed.  PREFER_NOSWITCH_P is true if a noswitch
1133    section should be used wherever possible.  */
1134 
1135 section *
get_variable_section(tree decl,bool prefer_noswitch_p)1136 get_variable_section (tree decl, bool prefer_noswitch_p)
1137 {
1138   addr_space_t as = ADDR_SPACE_GENERIC;
1139   int reloc;
1140   varpool_node *vnode = varpool_node::get (decl);
1141   if (vnode)
1142     {
1143       vnode = vnode->ultimate_alias_target ();
1144       decl = vnode->decl;
1145     }
1146 
1147   if (TREE_TYPE (decl) != error_mark_node)
1148     as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1149 
1150   /* We need the constructor to figure out reloc flag.  */
1151   if (vnode)
1152     vnode->get_constructor ();
1153 
1154   if (DECL_COMMON (decl))
1155     {
1156       /* If the decl has been given an explicit section name, or it resides
1157 	 in a non-generic address space, then it isn't common, and shouldn't
1158 	 be handled as such.  */
1159       gcc_assert (DECL_SECTION_NAME (decl) == NULL
1160 		  && ADDR_SPACE_GENERIC_P (as));
1161       if (DECL_THREAD_LOCAL_P (decl))
1162 	return tls_comm_section;
1163       else if (TREE_PUBLIC (decl) && bss_initializer_p (decl))
1164 	return comm_section;
1165     }
1166 
1167   if (DECL_INITIAL (decl) == error_mark_node)
1168     reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1169   else if (DECL_INITIAL (decl))
1170     reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1171   else
1172     reloc = 0;
1173 
1174   resolve_unique_section (decl, reloc, flag_data_sections);
1175   if (IN_NAMED_SECTION (decl))
1176     {
1177       section *sect = get_named_section (decl, NULL, reloc);
1178 
1179       if ((sect->common.flags & SECTION_BSS)
1180 	  && !bss_initializer_p (decl, true))
1181 	{
1182 	  error_at (DECL_SOURCE_LOCATION (decl),
1183 		    "only zero initializers are allowed in section %qs",
1184 		    sect->named.name);
1185 	  DECL_INITIAL (decl) = error_mark_node;
1186 	}
1187       return sect;
1188     }
1189 
1190   if (ADDR_SPACE_GENERIC_P (as)
1191       && !DECL_THREAD_LOCAL_P (decl)
1192       && !(prefer_noswitch_p && targetm.have_switchable_bss_sections)
1193       && bss_initializer_p (decl))
1194     {
1195       if (!TREE_PUBLIC (decl)
1196 	  && !((flag_sanitize & SANITIZE_ADDRESS)
1197 	       && asan_protect_global (decl)))
1198 	return lcomm_section;
1199       if (bss_noswitch_section)
1200 	return bss_noswitch_section;
1201     }
1202 
1203   return targetm.asm_out.select_section (decl, reloc,
1204 					 get_variable_align (decl));
1205 }
1206 
1207 /* Return the block into which object_block DECL should be placed.  */
1208 
1209 static struct object_block *
get_block_for_decl(tree decl)1210 get_block_for_decl (tree decl)
1211 {
1212   section *sect;
1213 
1214   if (VAR_P (decl))
1215     {
1216       /* The object must be defined in this translation unit.  */
1217       if (DECL_EXTERNAL (decl))
1218 	return NULL;
1219 
1220       /* There's no point using object blocks for something that is
1221 	 isolated by definition.  */
1222       if (DECL_COMDAT_GROUP (decl))
1223 	return NULL;
1224     }
1225 
1226   /* We can only calculate block offsets if the decl has a known
1227      constant size.  */
1228   if (DECL_SIZE_UNIT (decl) == NULL)
1229     return NULL;
1230   if (!tree_fits_uhwi_p (DECL_SIZE_UNIT (decl)))
1231     return NULL;
1232 
1233   /* Find out which section should contain DECL.  We cannot put it into
1234      an object block if it requires a standalone definition.  */
1235   if (VAR_P (decl))
1236       align_variable (decl, 0);
1237   sect = get_variable_section (decl, true);
1238   if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
1239     return NULL;
1240 
1241   return get_block_for_section (sect);
1242 }
1243 
1244 /* Make sure block symbol SYMBOL is in block BLOCK.  */
1245 
1246 static void
change_symbol_block(rtx symbol,struct object_block * block)1247 change_symbol_block (rtx symbol, struct object_block *block)
1248 {
1249   if (block != SYMBOL_REF_BLOCK (symbol))
1250     {
1251       gcc_assert (SYMBOL_REF_BLOCK_OFFSET (symbol) < 0);
1252       SYMBOL_REF_BLOCK (symbol) = block;
1253     }
1254 }
1255 
1256 /* Return true if it is possible to put DECL in an object_block.  */
1257 
1258 static bool
use_blocks_for_decl_p(tree decl)1259 use_blocks_for_decl_p (tree decl)
1260 {
1261   struct symtab_node *snode;
1262 
1263   /* Only data DECLs can be placed into object blocks.  */
1264   if (!VAR_P (decl) && TREE_CODE (decl) != CONST_DECL)
1265     return false;
1266 
1267   /* DECL_INITIAL (decl) set to decl is a hack used for some decls that
1268      are never used from code directly and we never want object block handling
1269      for those.  */
1270   if (DECL_INITIAL (decl) == decl)
1271     return false;
1272 
1273   /* If this decl is an alias, then we don't want to emit a
1274      definition.  */
1275   if (VAR_P (decl)
1276       && (snode = symtab_node::get (decl)) != NULL
1277       && snode->alias)
1278     return false;
1279 
1280   return targetm.use_blocks_for_decl_p (decl);
1281 }
1282 
1283 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS
1284    until we find an identifier that is not itself a transparent alias.
1285    Modify the alias passed to it by reference (and all aliases on the
1286    way to the ultimate target), such that they do not have to be
1287    followed again, and return the ultimate target of the alias
1288    chain.  */
1289 
1290 static inline tree
ultimate_transparent_alias_target(tree * alias)1291 ultimate_transparent_alias_target (tree *alias)
1292 {
1293   tree target = *alias;
1294 
1295   if (IDENTIFIER_TRANSPARENT_ALIAS (target))
1296     {
1297       gcc_assert (TREE_CHAIN (target));
1298       target = ultimate_transparent_alias_target (&TREE_CHAIN (target));
1299       gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target)
1300 		  && ! TREE_CHAIN (target));
1301       *alias = target;
1302     }
1303 
1304   return target;
1305 }
1306 
1307 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL.  DECL should
1308    have static storage duration.  In other words, it should not be an
1309    automatic variable, including PARM_DECLs.
1310 
1311    There is, however, one exception: this function handles variables
1312    explicitly placed in a particular register by the user.
1313 
1314    This is never called for PARM_DECL nodes.  */
1315 
1316 void
make_decl_rtl(tree decl)1317 make_decl_rtl (tree decl)
1318 {
1319   const char *name = 0;
1320   int reg_number;
1321   tree id;
1322   rtx x;
1323 
1324   /* Check that we are not being given an automatic variable.  */
1325   gcc_assert (TREE_CODE (decl) != PARM_DECL
1326 	      && TREE_CODE (decl) != RESULT_DECL);
1327 
1328   /* A weak alias has TREE_PUBLIC set but not the other bits.  */
1329   gcc_assert (!VAR_P (decl)
1330 	      || TREE_STATIC (decl)
1331 	      || TREE_PUBLIC (decl)
1332 	      || DECL_EXTERNAL (decl)
1333 	      || DECL_REGISTER (decl));
1334 
1335   /* And that we were not given a type or a label.  */
1336   gcc_assert (TREE_CODE (decl) != TYPE_DECL
1337 	      && TREE_CODE (decl) != LABEL_DECL);
1338 
1339   /* For a duplicate declaration, we can be called twice on the
1340      same DECL node.  Don't discard the RTL already made.  */
1341   if (DECL_RTL_SET_P (decl))
1342     {
1343       /* If the old RTL had the wrong mode, fix the mode.  */
1344       x = DECL_RTL (decl);
1345       if (GET_MODE (x) != DECL_MODE (decl))
1346 	SET_DECL_RTL (decl, adjust_address_nv (x, DECL_MODE (decl), 0));
1347 
1348       if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1349 	return;
1350 
1351       /* ??? Another way to do this would be to maintain a hashed
1352 	 table of such critters.  Instead of adding stuff to a DECL
1353 	 to give certain attributes to it, we could use an external
1354 	 hash map from DECL to set of attributes.  */
1355 
1356       /* Let the target reassign the RTL if it wants.
1357 	 This is necessary, for example, when one machine specific
1358 	 decl attribute overrides another.  */
1359       targetm.encode_section_info (decl, DECL_RTL (decl), false);
1360 
1361       /* If the symbol has a SYMBOL_REF_BLOCK field, update it based
1362 	 on the new decl information.  */
1363       if (MEM_P (x)
1364 	  && GET_CODE (XEXP (x, 0)) == SYMBOL_REF
1365 	  && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (x, 0)))
1366 	change_symbol_block (XEXP (x, 0), get_block_for_decl (decl));
1367 
1368       return;
1369     }
1370 
1371   /* If this variable belongs to the global constant pool, retrieve the
1372      pre-computed RTL or recompute it in LTO mode.  */
1373   if (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
1374     {
1375       SET_DECL_RTL (decl, output_constant_def (DECL_INITIAL (decl), 1));
1376       return;
1377     }
1378 
1379   id = DECL_ASSEMBLER_NAME (decl);
1380   if (TREE_CODE (decl) == FUNCTION_DECL
1381       && cgraph_node::get (decl)
1382       && cgraph_node::get (decl)->instrumentation_clone)
1383     ultimate_transparent_alias_target (&id);
1384   name = IDENTIFIER_POINTER (id);
1385 
1386   if (name[0] != '*' && TREE_CODE (decl) != FUNCTION_DECL
1387       && DECL_REGISTER (decl))
1388     {
1389       error ("register name not specified for %q+D", decl);
1390     }
1391   else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1392     {
1393       const char *asmspec = name+1;
1394       machine_mode mode = DECL_MODE (decl);
1395       reg_number = decode_reg_name (asmspec);
1396       /* First detect errors in declaring global registers.  */
1397       if (reg_number == -1)
1398 	error ("register name not specified for %q+D", decl);
1399       else if (reg_number < 0)
1400 	error ("invalid register name for %q+D", decl);
1401       else if (mode == BLKmode)
1402 	error ("data type of %q+D isn%'t suitable for a register",
1403 	       decl);
1404       else if (!in_hard_reg_set_p (accessible_reg_set, mode, reg_number))
1405 	error ("the register specified for %q+D cannot be accessed"
1406 	       " by the current target", decl);
1407       else if (!in_hard_reg_set_p (operand_reg_set, mode, reg_number))
1408 	error ("the register specified for %q+D is not general enough"
1409 	       " to be used as a register variable", decl);
1410       else if (!targetm.hard_regno_mode_ok (reg_number, mode))
1411 	error ("register specified for %q+D isn%'t suitable for data type",
1412                decl);
1413       /* Now handle properly declared static register variables.  */
1414       else
1415 	{
1416 	  int nregs;
1417 
1418 	  if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
1419 	    {
1420 	      DECL_INITIAL (decl) = 0;
1421 	      error ("global register variable has initial value");
1422 	    }
1423 	  if (TREE_THIS_VOLATILE (decl))
1424 	    warning (OPT_Wvolatile_register_var,
1425 		     "optimization may eliminate reads and/or "
1426 		     "writes to register variables");
1427 
1428 	  /* If the user specified one of the eliminables registers here,
1429 	     e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
1430 	     confused with that register and be eliminated.  This usage is
1431 	     somewhat suspect...  */
1432 
1433 	  SET_DECL_RTL (decl, gen_raw_REG (mode, reg_number));
1434 	  ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
1435 	  REG_USERVAR_P (DECL_RTL (decl)) = 1;
1436 
1437 	  if (TREE_STATIC (decl))
1438 	    {
1439 	      /* Make this register global, so not usable for anything
1440 		 else.  */
1441 #ifdef ASM_DECLARE_REGISTER_GLOBAL
1442 	      name = IDENTIFIER_POINTER (DECL_NAME (decl));
1443 	      ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
1444 #endif
1445 	      nregs = hard_regno_nregs (reg_number, mode);
1446 	      while (nregs > 0)
1447 		globalize_reg (decl, reg_number + --nregs);
1448 	    }
1449 
1450 	  /* As a register variable, it has no section.  */
1451 	  return;
1452 	}
1453       /* Avoid internal errors from invalid register
1454 	 specifications.  */
1455       SET_DECL_ASSEMBLER_NAME (decl, NULL_TREE);
1456       DECL_HARD_REGISTER (decl) = 0;
1457       /* Also avoid SSA inconsistencies by pretending this is an external
1458 	 decl now.  */
1459       DECL_EXTERNAL (decl) = 1;
1460       return;
1461     }
1462   /* Now handle ordinary static variables and functions (in memory).
1463      Also handle vars declared register invalidly.  */
1464   else if (name[0] == '*')
1465   {
1466 #ifdef REGISTER_PREFIX
1467     if (strlen (REGISTER_PREFIX) != 0)
1468       {
1469 	reg_number = decode_reg_name (name);
1470 	if (reg_number >= 0 || reg_number == -3)
1471 	  error ("register name given for non-register variable %q+D", decl);
1472       }
1473 #endif
1474   }
1475 
1476   /* Specifying a section attribute on a variable forces it into a
1477      non-.bss section, and thus it cannot be common.  */
1478   /* FIXME: In general this code should not be necessary because
1479      visibility pass is doing the same work.  But notice_global_symbol
1480      is called early and it needs to make DECL_RTL to get the name.
1481      we take care of recomputing the DECL_RTL after visibility is changed.  */
1482   if (VAR_P (decl)
1483       && (TREE_STATIC (decl) || DECL_EXTERNAL (decl))
1484       && DECL_SECTION_NAME (decl) != NULL
1485       && DECL_INITIAL (decl) == NULL_TREE
1486       && DECL_COMMON (decl))
1487     DECL_COMMON (decl) = 0;
1488 
1489   /* Variables can't be both common and weak.  */
1490   if (VAR_P (decl) && DECL_WEAK (decl))
1491     DECL_COMMON (decl) = 0;
1492 
1493   if (use_object_blocks_p () && use_blocks_for_decl_p (decl))
1494     x = create_block_symbol (name, get_block_for_decl (decl), -1);
1495   else
1496     {
1497       machine_mode address_mode = Pmode;
1498       if (TREE_TYPE (decl) != error_mark_node)
1499 	{
1500 	  addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1501 	  address_mode = targetm.addr_space.address_mode (as);
1502 	}
1503       x = gen_rtx_SYMBOL_REF (address_mode, name);
1504     }
1505   SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
1506   SET_SYMBOL_REF_DECL (x, decl);
1507 
1508   x = gen_rtx_MEM (DECL_MODE (decl), x);
1509   if (TREE_CODE (decl) != FUNCTION_DECL)
1510     set_mem_attributes (x, decl, 1);
1511   SET_DECL_RTL (decl, x);
1512 
1513   /* Optionally set flags or add text to the name to record information
1514      such as that it is a function name.
1515      If the name is changed, the macro ASM_OUTPUT_LABELREF
1516      will have to know how to strip this information.  */
1517   targetm.encode_section_info (decl, DECL_RTL (decl), true);
1518 }
1519 
1520 /* Like make_decl_rtl, but inhibit creation of new alias sets when
1521    calling make_decl_rtl.  Also, reset DECL_RTL before returning the
1522    rtl.  */
1523 
1524 rtx
make_decl_rtl_for_debug(tree decl)1525 make_decl_rtl_for_debug (tree decl)
1526 {
1527   unsigned int save_aliasing_flag;
1528   rtx rtl;
1529 
1530   if (DECL_RTL_SET_P (decl))
1531     return DECL_RTL (decl);
1532 
1533   /* Kludge alert!  Somewhere down the call chain, make_decl_rtl will
1534      call new_alias_set.  If running with -fcompare-debug, sometimes
1535      we do not want to create alias sets that will throw the alias
1536      numbers off in the comparison dumps.  So... clearing
1537      flag_strict_aliasing will keep new_alias_set() from creating a
1538      new set.  */
1539   save_aliasing_flag = flag_strict_aliasing;
1540   flag_strict_aliasing = 0;
1541 
1542   rtl = DECL_RTL (decl);
1543   /* Reset DECL_RTL back, as various parts of the compiler expects
1544      DECL_RTL set meaning it is actually going to be output.  */
1545   SET_DECL_RTL (decl, NULL);
1546 
1547   flag_strict_aliasing = save_aliasing_flag;
1548   return rtl;
1549 }
1550 
1551 /* Output a string of literal assembler code
1552    for an `asm' keyword used between functions.  */
1553 
1554 void
assemble_asm(tree string)1555 assemble_asm (tree string)
1556 {
1557   const char *p;
1558   app_enable ();
1559 
1560   if (TREE_CODE (string) == ADDR_EXPR)
1561     string = TREE_OPERAND (string, 0);
1562 
1563   p = TREE_STRING_POINTER (string);
1564   fprintf (asm_out_file, "%s%s\n", p[0] == '\t' ? "" : "\t", p);
1565 }
1566 
1567 /* Write the address of the entity given by SYMBOL to SEC.  */
1568 void
assemble_addr_to_section(rtx symbol,section * sec)1569 assemble_addr_to_section (rtx symbol, section *sec)
1570 {
1571   switch_to_section (sec);
1572   assemble_align (POINTER_SIZE);
1573   assemble_integer (symbol, POINTER_SIZE_UNITS, POINTER_SIZE, 1);
1574 }
1575 
1576 /* Return the numbered .ctors.N (if CONSTRUCTOR_P) or .dtors.N (if
1577    not) section for PRIORITY.  */
1578 section *
get_cdtor_priority_section(int priority,bool constructor_p)1579 get_cdtor_priority_section (int priority, bool constructor_p)
1580 {
1581   /* Buffer conservatively large enough for the full range of a 32-bit
1582      int plus the text below.  */
1583   char buf[18];
1584 
1585   /* ??? This only works reliably with the GNU linker.  */
1586   sprintf (buf, "%s.%.5u",
1587 	   constructor_p ? ".ctors" : ".dtors",
1588 	   /* Invert the numbering so the linker puts us in the proper
1589 	      order; constructors are run from right to left, and the
1590 	      linker sorts in increasing order.  */
1591 	   MAX_INIT_PRIORITY - priority);
1592   return get_section (buf, SECTION_WRITE, NULL);
1593 }
1594 
1595 void
default_named_section_asm_out_destructor(rtx symbol,int priority)1596 default_named_section_asm_out_destructor (rtx symbol, int priority)
1597 {
1598   section *sec;
1599 
1600   if (priority != DEFAULT_INIT_PRIORITY)
1601     sec = get_cdtor_priority_section (priority,
1602 				      /*constructor_p=*/false);
1603   else
1604     sec = get_section (".dtors", SECTION_WRITE, NULL);
1605 
1606   assemble_addr_to_section (symbol, sec);
1607 }
1608 
1609 #ifdef DTORS_SECTION_ASM_OP
1610 void
default_dtor_section_asm_out_destructor(rtx symbol,int priority ATTRIBUTE_UNUSED)1611 default_dtor_section_asm_out_destructor (rtx symbol,
1612 					 int priority ATTRIBUTE_UNUSED)
1613 {
1614   assemble_addr_to_section (symbol, dtors_section);
1615 }
1616 #endif
1617 
1618 void
default_named_section_asm_out_constructor(rtx symbol,int priority)1619 default_named_section_asm_out_constructor (rtx symbol, int priority)
1620 {
1621   section *sec;
1622 
1623   if (priority != DEFAULT_INIT_PRIORITY)
1624     sec = get_cdtor_priority_section (priority,
1625 				      /*constructor_p=*/true);
1626   else
1627     sec = get_section (".ctors", SECTION_WRITE, NULL);
1628 
1629   assemble_addr_to_section (symbol, sec);
1630 }
1631 
1632 #ifdef CTORS_SECTION_ASM_OP
1633 void
default_ctor_section_asm_out_constructor(rtx symbol,int priority ATTRIBUTE_UNUSED)1634 default_ctor_section_asm_out_constructor (rtx symbol,
1635 					  int priority ATTRIBUTE_UNUSED)
1636 {
1637   assemble_addr_to_section (symbol, ctors_section);
1638 }
1639 #endif
1640 
1641 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1642    a nonzero value if the constant pool should be output before the
1643    start of the function, or a zero value if the pool should output
1644    after the end of the function.  The default is to put it before the
1645    start.  */
1646 
1647 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1648 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1649 #endif
1650 
1651 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1652    to be output to assembler.
1653    Set first_global_object_name and weak_global_object_name as appropriate.  */
1654 
1655 void
notice_global_symbol(tree decl)1656 notice_global_symbol (tree decl)
1657 {
1658   const char **t = &first_global_object_name;
1659 
1660   if (first_global_object_name
1661       || !TREE_PUBLIC (decl)
1662       || DECL_EXTERNAL (decl)
1663       || !DECL_NAME (decl)
1664       || (VAR_P (decl) && DECL_HARD_REGISTER (decl))
1665       || (TREE_CODE (decl) != FUNCTION_DECL
1666 	  && (!VAR_P (decl)
1667 	      || (DECL_COMMON (decl)
1668 		  && (DECL_INITIAL (decl) == 0
1669 		      || DECL_INITIAL (decl) == error_mark_node)))))
1670     return;
1671 
1672   /* We win when global object is found, but it is useful to know about weak
1673      symbol as well so we can produce nicer unique names.  */
1674   if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl) || flag_shlib)
1675     t = &weak_global_object_name;
1676 
1677   if (!*t)
1678     {
1679       tree id = DECL_ASSEMBLER_NAME (decl);
1680       ultimate_transparent_alias_target (&id);
1681       *t = ggc_strdup (targetm.strip_name_encoding (IDENTIFIER_POINTER (id)));
1682     }
1683 }
1684 
1685 /* If not using flag_reorder_blocks_and_partition, decide early whether the
1686    current function goes into the cold section, so that targets can use
1687    current_function_section during RTL expansion.  DECL describes the
1688    function.  */
1689 
1690 void
decide_function_section(tree decl)1691 decide_function_section (tree decl)
1692 {
1693   first_function_block_is_cold = false;
1694 
1695  if (DECL_SECTION_NAME (decl))
1696     {
1697       struct cgraph_node *node = cgraph_node::get (current_function_decl);
1698       /* Calls to function_section rely on first_function_block_is_cold
1699 	 being accurate.  */
1700       first_function_block_is_cold = (node
1701 				      && node->frequency
1702 				      == NODE_FREQUENCY_UNLIKELY_EXECUTED);
1703     }
1704 
1705   in_cold_section_p = first_function_block_is_cold;
1706 }
1707 
1708 /* Get the function's name, as described by its RTL.  This may be
1709    different from the DECL_NAME name used in the source file.  */
1710 const char *
get_fnname_from_decl(tree decl)1711 get_fnname_from_decl (tree decl)
1712 {
1713   rtx x = DECL_RTL (decl);
1714   gcc_assert (MEM_P (x));
1715   x = XEXP (x, 0);
1716   gcc_assert (GET_CODE (x) == SYMBOL_REF);
1717   return XSTR (x, 0);
1718 }
1719 
1720 /* Output assembler code for the constant pool of a function and associated
1721    with defining the name of the function.  DECL describes the function.
1722    NAME is the function's name.  For the constant pool, we use the current
1723    constant pool data.  */
1724 
1725 void
assemble_start_function(tree decl,const char * fnname)1726 assemble_start_function (tree decl, const char *fnname)
1727 {
1728   int align;
1729   char tmp_label[100];
1730   bool hot_label_written = false;
1731 
1732   if (crtl->has_bb_partition)
1733     {
1734       ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTB", const_labelno);
1735       crtl->subsections.hot_section_label = ggc_strdup (tmp_label);
1736       ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDB", const_labelno);
1737       crtl->subsections.cold_section_label = ggc_strdup (tmp_label);
1738       ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTE", const_labelno);
1739       crtl->subsections.hot_section_end_label = ggc_strdup (tmp_label);
1740       ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDE", const_labelno);
1741       crtl->subsections.cold_section_end_label = ggc_strdup (tmp_label);
1742       const_labelno++;
1743       cold_function_name = NULL_TREE;
1744     }
1745   else
1746     {
1747       crtl->subsections.hot_section_label = NULL;
1748       crtl->subsections.cold_section_label = NULL;
1749       crtl->subsections.hot_section_end_label = NULL;
1750       crtl->subsections.cold_section_end_label = NULL;
1751     }
1752 
1753   /* The following code does not need preprocessing in the assembler.  */
1754 
1755   app_disable ();
1756 
1757   if (CONSTANT_POOL_BEFORE_FUNCTION)
1758     output_constant_pool (fnname, decl);
1759 
1760   align = symtab_node::get (decl)->definition_alignment ();
1761 
1762   /* Make sure the not and cold text (code) sections are properly
1763      aligned.  This is necessary here in the case where the function
1764      has both hot and cold sections, because we don't want to re-set
1765      the alignment when the section switch happens mid-function.  */
1766 
1767   if (crtl->has_bb_partition)
1768     {
1769       first_function_block_is_cold = false;
1770 
1771       switch_to_section (unlikely_text_section ());
1772       assemble_align (align);
1773       ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_label);
1774 
1775       /* When the function starts with a cold section, we need to explicitly
1776 	 align the hot section and write out the hot section label.
1777 	 But if the current function is a thunk, we do not have a CFG.  */
1778       if (!cfun->is_thunk
1779 	  && BB_PARTITION (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) == BB_COLD_PARTITION)
1780 	{
1781 	  switch_to_section (text_section);
1782 	  assemble_align (align);
1783 	  ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1784 	  hot_label_written = true;
1785 	  first_function_block_is_cold = true;
1786 	}
1787       in_cold_section_p = first_function_block_is_cold;
1788     }
1789 
1790 
1791   /* Switch to the correct text section for the start of the function.  */
1792 
1793   switch_to_section (function_section (decl));
1794   if (crtl->has_bb_partition && !hot_label_written)
1795     ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1796 
1797   /* Tell assembler to move to target machine's alignment for functions.  */
1798   align = floor_log2 (align / BITS_PER_UNIT);
1799   if (align > 0)
1800     {
1801       ASM_OUTPUT_ALIGN (asm_out_file, align);
1802     }
1803 
1804   /* Handle a user-specified function alignment.
1805      Note that we still need to align to DECL_ALIGN, as above,
1806      because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all.  */
1807   if (! DECL_USER_ALIGN (decl)
1808       && align_functions_log > align
1809       && optimize_function_for_speed_p (cfun))
1810     {
1811 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1812       int align_log = align_functions_log;
1813 #endif
1814       int max_skip = align_functions - 1;
1815       if (flag_limit_function_alignment && crtl->max_insn_address > 0
1816 	  && max_skip >= crtl->max_insn_address)
1817 	max_skip = crtl->max_insn_address - 1;
1818 
1819 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1820       ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file, align_log, max_skip);
1821 #else
1822       ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1823 #endif
1824     }
1825 
1826 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1827   ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1828 #endif
1829 
1830   if (!DECL_IGNORED_P (decl))
1831     (*debug_hooks->begin_function) (decl);
1832 
1833   /* Make function name accessible from other files, if appropriate.  */
1834 
1835   if (TREE_PUBLIC (decl)
1836       || (cgraph_node::get (decl)->instrumentation_clone
1837 	  && cgraph_node::get (decl)->instrumented_version
1838 	  && TREE_PUBLIC (cgraph_node::get (decl)->instrumented_version->decl)))
1839     {
1840       notice_global_symbol (decl);
1841 
1842       globalize_decl (decl);
1843 
1844       maybe_assemble_visibility (decl);
1845     }
1846 
1847   if (DECL_PRESERVE_P (decl))
1848     targetm.asm_out.mark_decl_preserved (fnname);
1849 
1850   unsigned HOST_WIDE_INT patch_area_size = function_entry_patch_area_size;
1851   unsigned HOST_WIDE_INT patch_area_entry = function_entry_patch_area_start;
1852 
1853   tree patchable_function_entry_attr
1854     = lookup_attribute ("patchable_function_entry", DECL_ATTRIBUTES (decl));
1855   if (patchable_function_entry_attr)
1856     {
1857       tree pp_val = TREE_VALUE (patchable_function_entry_attr);
1858       tree patchable_function_entry_value1 = TREE_VALUE (pp_val);
1859 
1860       patch_area_size = tree_to_uhwi (patchable_function_entry_value1);
1861       patch_area_entry = 0;
1862       if (TREE_CHAIN (pp_val) != NULL_TREE)
1863 	{
1864 	  tree patchable_function_entry_value2
1865 	    = TREE_VALUE (TREE_CHAIN (pp_val));
1866 	  patch_area_entry = tree_to_uhwi (patchable_function_entry_value2);
1867 	}
1868     }
1869 
1870   if (patch_area_entry > patch_area_size)
1871     {
1872       if (patch_area_size > 0)
1873 	warning (OPT_Wattributes, "patchable function entry > size");
1874       patch_area_entry = 0;
1875     }
1876 
1877   /* Emit the patching area before the entry label, if any.  */
1878   if (patch_area_entry > 0)
1879     targetm.asm_out.print_patchable_function_entry (asm_out_file,
1880 						    patch_area_entry, true);
1881 
1882   /* Do any machine/system dependent processing of the function name.  */
1883 #ifdef ASM_DECLARE_FUNCTION_NAME
1884   ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1885 #else
1886   /* Standard thing is just output label for the function.  */
1887   ASM_OUTPUT_FUNCTION_LABEL (asm_out_file, fnname, current_function_decl);
1888 #endif /* ASM_DECLARE_FUNCTION_NAME */
1889 
1890   /* And the area after the label.  Record it if we haven't done so yet.  */
1891   if (patch_area_size > patch_area_entry)
1892     targetm.asm_out.print_patchable_function_entry (asm_out_file,
1893 						    patch_area_size
1894 						    - patch_area_entry,
1895 						    patch_area_entry == 0);
1896 
1897   if (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (decl)))
1898     saw_no_split_stack = true;
1899 }
1900 
1901 /* Output assembler code associated with defining the size of the
1902    function.  DECL describes the function.  NAME is the function's name.  */
1903 
1904 void
assemble_end_function(tree decl,const char * fnname ATTRIBUTE_UNUSED)1905 assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED)
1906 {
1907 #ifdef ASM_DECLARE_FUNCTION_SIZE
1908   /* We could have switched section in the middle of the function.  */
1909   if (crtl->has_bb_partition)
1910     switch_to_section (function_section (decl));
1911   ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1912 #endif
1913   if (! CONSTANT_POOL_BEFORE_FUNCTION)
1914     {
1915       output_constant_pool (fnname, decl);
1916       switch_to_section (function_section (decl)); /* need to switch back */
1917     }
1918   /* Output labels for end of hot/cold text sections (to be used by
1919      debug info.)  */
1920   if (crtl->has_bb_partition)
1921     {
1922       section *save_text_section;
1923 
1924       save_text_section = in_section;
1925       switch_to_section (unlikely_text_section ());
1926 #ifdef ASM_DECLARE_COLD_FUNCTION_SIZE
1927       if (cold_function_name != NULL_TREE)
1928 	ASM_DECLARE_COLD_FUNCTION_SIZE (asm_out_file,
1929 					IDENTIFIER_POINTER (cold_function_name),
1930 					decl);
1931 #endif
1932       ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label);
1933       if (first_function_block_is_cold)
1934 	switch_to_section (text_section);
1935       else
1936 	switch_to_section (function_section (decl));
1937       ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label);
1938       switch_to_section (save_text_section);
1939     }
1940 }
1941 
1942 /* Assemble code to leave SIZE bytes of zeros.  */
1943 
1944 void
assemble_zeros(unsigned HOST_WIDE_INT size)1945 assemble_zeros (unsigned HOST_WIDE_INT size)
1946 {
1947   /* Do no output if -fsyntax-only.  */
1948   if (flag_syntax_only)
1949     return;
1950 
1951 #ifdef ASM_NO_SKIP_IN_TEXT
1952   /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1953      so we must output 0s explicitly in the text section.  */
1954   if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0)
1955     {
1956       unsigned HOST_WIDE_INT i;
1957       for (i = 0; i < size; i++)
1958 	assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1959     }
1960   else
1961 #endif
1962     if (size > 0)
1963       ASM_OUTPUT_SKIP (asm_out_file, size);
1964 }
1965 
1966 /* Assemble an alignment pseudo op for an ALIGN-bit boundary.  */
1967 
1968 void
assemble_align(int align)1969 assemble_align (int align)
1970 {
1971   if (align > BITS_PER_UNIT)
1972     {
1973       ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1974     }
1975 }
1976 
1977 /* Assemble a string constant with the specified C string as contents.  */
1978 
1979 void
assemble_string(const char * p,int size)1980 assemble_string (const char *p, int size)
1981 {
1982   int pos = 0;
1983   int maximum = 2000;
1984 
1985   /* If the string is very long, split it up.  */
1986 
1987   while (pos < size)
1988     {
1989       int thissize = size - pos;
1990       if (thissize > maximum)
1991 	thissize = maximum;
1992 
1993       ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1994 
1995       pos += thissize;
1996       p += thissize;
1997     }
1998 }
1999 
2000 
2001 /* A noswitch_section_callback for lcomm_section.  */
2002 
2003 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)2004 emit_local (tree decl ATTRIBUTE_UNUSED,
2005 	    const char *name ATTRIBUTE_UNUSED,
2006 	    unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2007 	    unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2008 {
2009 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
2010   unsigned int align = symtab_node::get (decl)->definition_alignment ();
2011   ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name,
2012 				 size, align);
2013   return true;
2014 #elif defined ASM_OUTPUT_ALIGNED_LOCAL
2015   unsigned int align = symtab_node::get (decl)->definition_alignment ();
2016   ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, align);
2017   return true;
2018 #else
2019   ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2020   return false;
2021 #endif
2022 }
2023 
2024 /* A noswitch_section_callback for bss_noswitch_section.  */
2025 
2026 #if defined ASM_OUTPUT_ALIGNED_BSS
2027 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)2028 emit_bss (tree decl ATTRIBUTE_UNUSED,
2029 	  const char *name ATTRIBUTE_UNUSED,
2030 	  unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2031 	  unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2032 {
2033   ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size,
2034 			  get_variable_align (decl));
2035   return true;
2036 }
2037 #endif
2038 
2039 /* A noswitch_section_callback for comm_section.  */
2040 
2041 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)2042 emit_common (tree decl ATTRIBUTE_UNUSED,
2043 	     const char *name ATTRIBUTE_UNUSED,
2044 	     unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2045 	     unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2046 {
2047 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
2048   ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name,
2049 				  size, get_variable_align (decl));
2050   return true;
2051 #elif defined ASM_OUTPUT_ALIGNED_COMMON
2052   ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size,
2053 			     get_variable_align (decl));
2054   return true;
2055 #else
2056   ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
2057   return false;
2058 #endif
2059 }
2060 
2061 /* A noswitch_section_callback for tls_comm_section.  */
2062 
2063 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)2064 emit_tls_common (tree decl ATTRIBUTE_UNUSED,
2065 		 const char *name ATTRIBUTE_UNUSED,
2066 		 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2067 		 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2068 {
2069 #ifdef ASM_OUTPUT_TLS_COMMON
2070   ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size);
2071   return true;
2072 #else
2073   sorry ("thread-local COMMON data not implemented");
2074   return true;
2075 #endif
2076 }
2077 
2078 /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT.
2079    NAME is the name of DECL's SYMBOL_REF.  */
2080 
2081 static void
assemble_noswitch_variable(tree decl,const char * name,section * sect,unsigned int align)2082 assemble_noswitch_variable (tree decl, const char *name, section *sect,
2083 			    unsigned int align)
2084 {
2085   unsigned HOST_WIDE_INT size, rounded;
2086 
2087   size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2088   rounded = size;
2089 
2090   if ((flag_sanitize & SANITIZE_ADDRESS) && asan_protect_global (decl))
2091     size += asan_red_zone_size (size);
2092 
2093   /* Don't allocate zero bytes of common,
2094      since that means "undefined external" in the linker.  */
2095   if (size == 0)
2096     rounded = 1;
2097 
2098   /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2099      so that each uninitialized object starts on such a boundary.  */
2100   rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
2101   rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2102 	     * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2103 
2104   if (!sect->noswitch.callback (decl, name, size, rounded)
2105       && (unsigned HOST_WIDE_INT) (align / BITS_PER_UNIT) > rounded)
2106     error ("requested alignment for %q+D is greater than "
2107 	   "implemented alignment of %wu", decl, rounded);
2108 }
2109 
2110 /* A subroutine of assemble_variable.  Output the label and contents of
2111    DECL, whose address is a SYMBOL_REF with name NAME.  DONT_OUTPUT_DATA
2112    is as for assemble_variable.  */
2113 
2114 static void
assemble_variable_contents(tree decl,const char * name,bool dont_output_data)2115 assemble_variable_contents (tree decl, const char *name,
2116 			    bool dont_output_data)
2117 {
2118   /* Do any machine/system dependent processing of the object.  */
2119 #ifdef ASM_DECLARE_OBJECT_NAME
2120   last_assemble_variable_decl = decl;
2121   ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
2122 #else
2123   /* Standard thing is just output label for the object.  */
2124   ASM_OUTPUT_LABEL (asm_out_file, name);
2125 #endif /* ASM_DECLARE_OBJECT_NAME */
2126 
2127   if (!dont_output_data)
2128     {
2129       /* Caller is supposed to use varpool_get_constructor when it wants
2130 	 to output the body.  */
2131       gcc_assert (!in_lto_p || DECL_INITIAL (decl) != error_mark_node);
2132       if (DECL_INITIAL (decl)
2133 	  && DECL_INITIAL (decl) != error_mark_node
2134 	  && !initializer_zerop (DECL_INITIAL (decl)))
2135 	/* Output the actual data.  */
2136 	output_constant (DECL_INITIAL (decl),
2137 			 tree_to_uhwi (DECL_SIZE_UNIT (decl)),
2138 			 get_variable_align (decl),
2139 			 false);
2140       else
2141 	/* Leave space for it.  */
2142 	assemble_zeros (tree_to_uhwi (DECL_SIZE_UNIT (decl)));
2143       targetm.asm_out.decl_end ();
2144     }
2145 }
2146 
2147 /* Write out assembly for the variable DECL, which is not defined in
2148    the current translation unit.  */
2149 void
assemble_undefined_decl(tree decl)2150 assemble_undefined_decl (tree decl)
2151 {
2152   const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
2153   targetm.asm_out.assemble_undefined_decl (asm_out_file, name, decl);
2154 }
2155 
2156 /* Assemble everything that is needed for a variable or function declaration.
2157    Not used for automatic variables, and not used for function definitions.
2158    Should not be called for variables of incomplete structure type.
2159 
2160    TOP_LEVEL is nonzero if this variable has file scope.
2161    AT_END is nonzero if this is the special handling, at end of compilation,
2162    to define things that have had only tentative definitions.
2163    DONT_OUTPUT_DATA if nonzero means don't actually output the
2164    initial value (that will be done by the caller).  */
2165 
2166 void
assemble_variable(tree decl,int top_level ATTRIBUTE_UNUSED,int at_end ATTRIBUTE_UNUSED,int dont_output_data)2167 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
2168 		   int at_end ATTRIBUTE_UNUSED, int dont_output_data)
2169 {
2170   const char *name;
2171   rtx decl_rtl, symbol;
2172   section *sect;
2173   unsigned int align;
2174   bool asan_protected = false;
2175 
2176   /* This function is supposed to handle VARIABLES.  Ensure we have one.  */
2177   gcc_assert (VAR_P (decl));
2178 
2179   /* Emulated TLS had better not get this far.  */
2180   gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl));
2181 
2182   last_assemble_variable_decl = 0;
2183 
2184   /* Normally no need to say anything here for external references,
2185      since assemble_external is called by the language-specific code
2186      when a declaration is first seen.  */
2187 
2188   if (DECL_EXTERNAL (decl))
2189     return;
2190 
2191   /* Do nothing for global register variables.  */
2192   if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
2193     {
2194       TREE_ASM_WRITTEN (decl) = 1;
2195       return;
2196     }
2197 
2198   /* If type was incomplete when the variable was declared,
2199      see if it is complete now.  */
2200 
2201   if (DECL_SIZE (decl) == 0)
2202     layout_decl (decl, 0);
2203 
2204   /* Still incomplete => don't allocate it; treat the tentative defn
2205      (which is what it must have been) as an `extern' reference.  */
2206 
2207   if (!dont_output_data && DECL_SIZE (decl) == 0)
2208     {
2209       error ("storage size of %q+D isn%'t known", decl);
2210       TREE_ASM_WRITTEN (decl) = 1;
2211       return;
2212     }
2213 
2214   /* The first declaration of a variable that comes through this function
2215      decides whether it is global (in C, has external linkage)
2216      or local (in C, has internal linkage).  So do nothing more
2217      if this function has already run.  */
2218 
2219   if (TREE_ASM_WRITTEN (decl))
2220     return;
2221 
2222   /* Make sure targetm.encode_section_info is invoked before we set
2223      ASM_WRITTEN.  */
2224   decl_rtl = DECL_RTL (decl);
2225 
2226   TREE_ASM_WRITTEN (decl) = 1;
2227 
2228   /* Do no output if -fsyntax-only.  */
2229   if (flag_syntax_only)
2230     return;
2231 
2232   if (! dont_output_data
2233       && ! valid_constant_size_p (DECL_SIZE_UNIT (decl)))
2234     {
2235       error ("size of variable %q+D is too large", decl);
2236       return;
2237     }
2238 
2239   gcc_assert (MEM_P (decl_rtl));
2240   gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF);
2241   symbol = XEXP (decl_rtl, 0);
2242 
2243   /* If this symbol belongs to the tree constant pool, output the constant
2244      if it hasn't already been written.  */
2245   if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
2246     {
2247       tree decl = SYMBOL_REF_DECL (symbol);
2248       if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
2249 	output_constant_def_contents (symbol);
2250       return;
2251     }
2252 
2253   app_disable ();
2254 
2255   name = XSTR (symbol, 0);
2256   if (TREE_PUBLIC (decl) && DECL_NAME (decl))
2257     notice_global_symbol (decl);
2258 
2259   /* Compute the alignment of this data.  */
2260 
2261   align_variable (decl, dont_output_data);
2262 
2263   if ((flag_sanitize & SANITIZE_ADDRESS)
2264       && asan_protect_global (decl))
2265     {
2266       asan_protected = true;
2267       SET_DECL_ALIGN (decl, MAX (DECL_ALIGN (decl),
2268 				 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT));
2269     }
2270 
2271   set_mem_align (decl_rtl, DECL_ALIGN (decl));
2272 
2273   align = get_variable_align (decl);
2274 
2275   if (TREE_PUBLIC (decl))
2276     maybe_assemble_visibility (decl);
2277 
2278   if (DECL_PRESERVE_P (decl))
2279     targetm.asm_out.mark_decl_preserved (name);
2280 
2281   /* First make the assembler name(s) global if appropriate.  */
2282   sect = get_variable_section (decl, false);
2283   if (TREE_PUBLIC (decl)
2284       && (sect->common.flags & SECTION_COMMON) == 0)
2285     globalize_decl (decl);
2286 
2287   /* Output any data that we will need to use the address of.  */
2288   if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
2289     output_addressed_constants (DECL_INITIAL (decl));
2290 
2291   /* dbxout.c needs to know this.  */
2292   if (sect && (sect->common.flags & SECTION_CODE) != 0)
2293     DECL_IN_TEXT_SECTION (decl) = 1;
2294 
2295   /* If the decl is part of an object_block, make sure that the decl
2296      has been positioned within its block, but do not write out its
2297      definition yet.  output_object_blocks will do that later.  */
2298   if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
2299     {
2300       gcc_assert (!dont_output_data);
2301       place_block_symbol (symbol);
2302     }
2303   else if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
2304     assemble_noswitch_variable (decl, name, sect, align);
2305   else
2306     {
2307       /* Special-case handling of vtv comdat sections.  */
2308       if (sect->named.name
2309 	  && (strcmp (sect->named.name, ".vtable_map_vars") == 0))
2310 	handle_vtv_comdat_section (sect, decl);
2311       else
2312 	switch_to_section (sect);
2313       if (align > BITS_PER_UNIT)
2314 	ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2315       assemble_variable_contents (decl, name, dont_output_data);
2316       if (asan_protected)
2317 	{
2318 	  unsigned HOST_WIDE_INT int size
2319 	    = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2320 	  assemble_zeros (asan_red_zone_size (size));
2321 	}
2322     }
2323 }
2324 
2325 
2326 /* Given a function declaration (FN_DECL), this function assembles the
2327    function into the .preinit_array section.  */
2328 
2329 void
assemble_vtv_preinit_initializer(tree fn_decl)2330 assemble_vtv_preinit_initializer (tree fn_decl)
2331 {
2332   section *sect;
2333   unsigned flags = SECTION_WRITE;
2334   rtx symbol = XEXP (DECL_RTL (fn_decl), 0);
2335 
2336   flags |= SECTION_NOTYPE;
2337   sect = get_section (".preinit_array", flags, fn_decl);
2338   switch_to_section (sect);
2339   assemble_addr_to_section (symbol, sect);
2340 }
2341 
2342 /* Return 1 if type TYPE contains any pointers.  */
2343 
2344 static int
contains_pointers_p(tree type)2345 contains_pointers_p (tree type)
2346 {
2347   switch (TREE_CODE (type))
2348     {
2349     case POINTER_TYPE:
2350     case REFERENCE_TYPE:
2351       /* I'm not sure whether OFFSET_TYPE needs this treatment,
2352 	 so I'll play safe and return 1.  */
2353     case OFFSET_TYPE:
2354       return 1;
2355 
2356     case RECORD_TYPE:
2357     case UNION_TYPE:
2358     case QUAL_UNION_TYPE:
2359       {
2360 	tree fields;
2361 	/* For a type that has fields, see if the fields have pointers.  */
2362 	for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2363 	  if (TREE_CODE (fields) == FIELD_DECL
2364 	      && contains_pointers_p (TREE_TYPE (fields)))
2365 	    return 1;
2366 	return 0;
2367       }
2368 
2369     case ARRAY_TYPE:
2370       /* An array type contains pointers if its element type does.  */
2371       return contains_pointers_p (TREE_TYPE (type));
2372 
2373     default:
2374       return 0;
2375     }
2376 }
2377 
2378 /* We delay assemble_external processing until
2379    the compilation unit is finalized.  This is the best we can do for
2380    right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2381    it all the way to final.  See PR 17982 for further discussion.  */
2382 static GTY(()) tree pending_assemble_externals;
2383 
2384 #ifdef ASM_OUTPUT_EXTERNAL
2385 /* Some targets delay some output to final using TARGET_ASM_FILE_END.
2386    As a result, assemble_external can be called after the list of externals
2387    is processed and the pointer set destroyed.  */
2388 static bool pending_assemble_externals_processed;
2389 
2390 /* Avoid O(external_decls**2) lookups in the pending_assemble_externals
2391    TREE_LIST in assemble_external.  */
2392 static hash_set<tree> *pending_assemble_externals_set;
2393 
2394 /* True if DECL is a function decl for which no out-of-line copy exists.
2395    It is assumed that DECL's assembler name has been set.  */
2396 
2397 static bool
incorporeal_function_p(tree decl)2398 incorporeal_function_p (tree decl)
2399 {
2400   if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
2401     {
2402       const char *name;
2403 
2404       if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2405 	  && ALLOCA_FUNCTION_CODE_P (DECL_FUNCTION_CODE (decl)))
2406 	return true;
2407 
2408       name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2409       /* Atomic or sync builtins which have survived this far will be
2410 	 resolved externally and therefore are not incorporeal.  */
2411       if (strncmp (name, "__builtin_", 10) == 0)
2412 	return true;
2413     }
2414   return false;
2415 }
2416 
2417 /* Actually do the tests to determine if this is necessary, and invoke
2418    ASM_OUTPUT_EXTERNAL.  */
2419 static void
assemble_external_real(tree decl)2420 assemble_external_real (tree decl)
2421 {
2422   rtx rtl = DECL_RTL (decl);
2423 
2424   if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2425       && !SYMBOL_REF_USED (XEXP (rtl, 0))
2426       && !incorporeal_function_p (decl))
2427     {
2428       /* Some systems do require some output.  */
2429       SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2430       ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2431     }
2432 }
2433 #endif
2434 
2435 void
process_pending_assemble_externals(void)2436 process_pending_assemble_externals (void)
2437 {
2438 #ifdef ASM_OUTPUT_EXTERNAL
2439   tree list;
2440   for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2441     assemble_external_real (TREE_VALUE (list));
2442 
2443   pending_assemble_externals = 0;
2444   pending_assemble_externals_processed = true;
2445   delete pending_assemble_externals_set;
2446 #endif
2447 }
2448 
2449 /* This TREE_LIST contains any weak symbol declarations waiting
2450    to be emitted.  */
2451 static GTY(()) tree weak_decls;
2452 
2453 /* Output something to declare an external symbol to the assembler,
2454    and qualifiers such as weakness.  (Most assemblers don't need
2455    extern declaration, so we normally output nothing.)  Do nothing if
2456    DECL is not external.  */
2457 
2458 void
assemble_external(tree decl ATTRIBUTE_UNUSED)2459 assemble_external (tree decl ATTRIBUTE_UNUSED)
2460 {
2461   /*  Make sure that the ASM_OUT_FILE is open.
2462       If it's not, we should not be calling this function.  */
2463   gcc_assert (asm_out_file);
2464 
2465   /* In a perfect world, the following condition would be true.
2466      Sadly, the Go front end emit assembly *from the front end*,
2467      bypassing the call graph.  See PR52739.  Fix before GCC 4.8.  */
2468 #if 0
2469   /* This function should only be called if we are expanding, or have
2470      expanded, to RTL.
2471      Ideally, only final.c would be calling this function, but it is
2472      not clear whether that would break things somehow.  See PR 17982
2473      for further discussion.  */
2474   gcc_assert (state == EXPANSION
2475 	      || state == FINISHED);
2476 #endif
2477 
2478   if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2479     return;
2480 
2481   /* We want to output annotation for weak and external symbols at
2482      very last to check if they are references or not.  */
2483 
2484   if (TARGET_SUPPORTS_WEAK
2485       && DECL_WEAK (decl)
2486       /* TREE_STATIC is a weird and abused creature which is not
2487 	 generally the right test for whether an entity has been
2488 	 locally emitted, inlined or otherwise not-really-extern, but
2489 	 for declarations that can be weak, it happens to be
2490 	 match.  */
2491       && !TREE_STATIC (decl)
2492       && lookup_attribute ("weak", DECL_ATTRIBUTES (decl))
2493       && value_member (decl, weak_decls) == NULL_TREE)
2494     weak_decls = tree_cons (NULL, decl, weak_decls);
2495 
2496 #ifdef ASM_OUTPUT_EXTERNAL
2497   if (pending_assemble_externals_processed)
2498     {
2499       assemble_external_real (decl);
2500       return;
2501     }
2502 
2503   if (! pending_assemble_externals_set->add (decl))
2504     pending_assemble_externals = tree_cons (NULL, decl,
2505 					    pending_assemble_externals);
2506 #endif
2507 }
2508 
2509 /* Similar, for calling a library function FUN.  */
2510 
2511 void
assemble_external_libcall(rtx fun)2512 assemble_external_libcall (rtx fun)
2513 {
2514   /* Declare library function name external when first used, if nec.  */
2515   if (! SYMBOL_REF_USED (fun))
2516     {
2517       SYMBOL_REF_USED (fun) = 1;
2518       targetm.asm_out.external_libcall (fun);
2519     }
2520 }
2521 
2522 /* Assemble a label named NAME.  */
2523 
2524 void
assemble_label(FILE * file,const char * name)2525 assemble_label (FILE *file, const char *name)
2526 {
2527   ASM_OUTPUT_LABEL (file, name);
2528 }
2529 
2530 /* Set the symbol_referenced flag for ID.  */
2531 void
mark_referenced(tree id)2532 mark_referenced (tree id)
2533 {
2534   TREE_SYMBOL_REFERENCED (id) = 1;
2535 }
2536 
2537 /* Set the symbol_referenced flag for DECL and notify callgraph.  */
2538 void
mark_decl_referenced(tree decl)2539 mark_decl_referenced (tree decl)
2540 {
2541   if (TREE_CODE (decl) == FUNCTION_DECL)
2542     {
2543       /* Extern inline functions don't become needed when referenced.
2544 	 If we know a method will be emitted in other TU and no new
2545 	 functions can be marked reachable, just use the external
2546 	 definition.  */
2547       struct cgraph_node *node = cgraph_node::get_create (decl);
2548       if (!DECL_EXTERNAL (decl)
2549 	  && !node->definition)
2550 	node->mark_force_output ();
2551     }
2552   else if (VAR_P (decl))
2553     {
2554       varpool_node *node = varpool_node::get_create (decl);
2555       /* C++ frontend use mark_decl_references to force COMDAT variables
2556          to be output that might appear dead otherwise.  */
2557       node->force_output = true;
2558     }
2559   /* else do nothing - we can get various sorts of CST nodes here,
2560      which do not need to be marked.  */
2561 }
2562 
2563 
2564 /* Output to FILE (an assembly file) a reference to NAME.  If NAME
2565    starts with a *, the rest of NAME is output verbatim.  Otherwise
2566    NAME is transformed in a target-specific way (usually by the
2567    addition of an underscore).  */
2568 
2569 void
assemble_name_raw(FILE * file,const char * name)2570 assemble_name_raw (FILE *file, const char *name)
2571 {
2572   if (name[0] == '*')
2573     fputs (&name[1], file);
2574   else
2575     ASM_OUTPUT_LABELREF (file, name);
2576 }
2577 
2578 /* Return NAME that should actually be emitted, looking through
2579    transparent aliases.  If NAME refers to an entity that is also
2580    represented as a tree (like a function or variable), mark the entity
2581    as referenced.  */
2582 const char *
assemble_name_resolve(const char * name)2583 assemble_name_resolve (const char *name)
2584 {
2585   const char *real_name = targetm.strip_name_encoding (name);
2586   tree id = maybe_get_identifier (real_name);
2587 
2588   if (id)
2589     {
2590       tree id_orig = id;
2591 
2592       mark_referenced (id);
2593       ultimate_transparent_alias_target (&id);
2594       if (id != id_orig)
2595 	name = IDENTIFIER_POINTER (id);
2596       gcc_assert (! TREE_CHAIN (id));
2597     }
2598 
2599   return name;
2600 }
2601 
2602 /* Like assemble_name_raw, but should be used when NAME might refer to
2603    an entity that is also represented as a tree (like a function or
2604    variable).  If NAME does refer to such an entity, that entity will
2605    be marked as referenced.  */
2606 
2607 void
assemble_name(FILE * file,const char * name)2608 assemble_name (FILE *file, const char *name)
2609 {
2610   assemble_name_raw (file, assemble_name_resolve (name));
2611 }
2612 
2613 /* Allocate SIZE bytes writable static space with a gensym name
2614    and return an RTX to refer to its address.  */
2615 
2616 rtx
assemble_static_space(unsigned HOST_WIDE_INT size)2617 assemble_static_space (unsigned HOST_WIDE_INT size)
2618 {
2619   char name[17];
2620   const char *namestring;
2621   rtx x;
2622 
2623   ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2624   ++const_labelno;
2625   namestring = ggc_strdup (name);
2626 
2627   x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2628   SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2629 
2630 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2631   ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2632 				 BIGGEST_ALIGNMENT);
2633 #else
2634 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2635   ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2636 #else
2637   {
2638     /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2639        so that each uninitialized object starts on such a boundary.  */
2640     /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL.  */
2641     unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2642       = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2643 	 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2644 	 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2645     ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2646   }
2647 #endif
2648 #endif
2649   return x;
2650 }
2651 
2652 /* Assemble the static constant template for function entry trampolines.
2653    This is done at most once per compilation.
2654    Returns an RTX for the address of the template.  */
2655 
2656 static GTY(()) rtx initial_trampoline;
2657 
2658 rtx
assemble_trampoline_template(void)2659 assemble_trampoline_template (void)
2660 {
2661   char label[256];
2662   const char *name;
2663   int align;
2664   rtx symbol;
2665 
2666   gcc_assert (targetm.asm_out.trampoline_template != NULL);
2667 
2668   if (initial_trampoline)
2669     return initial_trampoline;
2670 
2671   /* By default, put trampoline templates in read-only data section.  */
2672 
2673 #ifdef TRAMPOLINE_SECTION
2674   switch_to_section (TRAMPOLINE_SECTION);
2675 #else
2676   switch_to_section (readonly_data_section);
2677 #endif
2678 
2679   /* Write the assembler code to define one.  */
2680   align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2681   if (align > 0)
2682     ASM_OUTPUT_ALIGN (asm_out_file, align);
2683 
2684   targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2685   targetm.asm_out.trampoline_template (asm_out_file);
2686 
2687   /* Record the rtl to refer to it.  */
2688   ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2689   name = ggc_strdup (label);
2690   symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2691   SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2692 
2693   initial_trampoline = gen_const_mem (BLKmode, symbol);
2694   set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2695   set_mem_size (initial_trampoline, TRAMPOLINE_SIZE);
2696 
2697   return initial_trampoline;
2698 }
2699 
2700 /* A and B are either alignments or offsets.  Return the minimum alignment
2701    that may be assumed after adding the two together.  */
2702 
2703 static inline unsigned
min_align(unsigned int a,unsigned int b)2704 min_align (unsigned int a, unsigned int b)
2705 {
2706   return least_bit_hwi (a | b);
2707 }
2708 
2709 /* Return the assembler directive for creating a given kind of integer
2710    object.  SIZE is the number of bytes in the object and ALIGNED_P
2711    indicates whether it is known to be aligned.  Return NULL if the
2712    assembly dialect has no such directive.
2713 
2714    The returned string should be printed at the start of a new line and
2715    be followed immediately by the object's initial value.  */
2716 
2717 const char *
integer_asm_op(int size,int aligned_p)2718 integer_asm_op (int size, int aligned_p)
2719 {
2720   struct asm_int_op *ops;
2721 
2722   if (aligned_p)
2723     ops = &targetm.asm_out.aligned_op;
2724   else
2725     ops = &targetm.asm_out.unaligned_op;
2726 
2727   switch (size)
2728     {
2729     case 1:
2730       return targetm.asm_out.byte_op;
2731     case 2:
2732       return ops->hi;
2733     case 4:
2734       return ops->si;
2735     case 8:
2736       return ops->di;
2737     case 16:
2738       return ops->ti;
2739     default:
2740       return NULL;
2741     }
2742 }
2743 
2744 /* Use directive OP to assemble an integer object X.  Print OP at the
2745    start of the line, followed immediately by the value of X.  */
2746 
2747 void
assemble_integer_with_op(const char * op,rtx x)2748 assemble_integer_with_op (const char *op, rtx x)
2749 {
2750   fputs (op, asm_out_file);
2751   output_addr_const (asm_out_file, x);
2752   fputc ('\n', asm_out_file);
2753 }
2754 
2755 /* The default implementation of the asm_out.integer target hook.  */
2756 
2757 bool
default_assemble_integer(rtx x ATTRIBUTE_UNUSED,unsigned int size ATTRIBUTE_UNUSED,int aligned_p ATTRIBUTE_UNUSED)2758 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2759 			  unsigned int size ATTRIBUTE_UNUSED,
2760 			  int aligned_p ATTRIBUTE_UNUSED)
2761 {
2762   const char *op = integer_asm_op (size, aligned_p);
2763   /* Avoid GAS bugs for large values.  Specifically negative values whose
2764      absolute value fits in a bfd_vma, but not in a bfd_signed_vma.  */
2765   if (size > UNITS_PER_WORD && size > POINTER_SIZE_UNITS)
2766     return false;
2767   return op && (assemble_integer_with_op (op, x), true);
2768 }
2769 
2770 /* Assemble the integer constant X into an object of SIZE bytes.  ALIGN is
2771    the alignment of the integer in bits.  Return 1 if we were able to output
2772    the constant, otherwise 0.  We must be able to output the constant,
2773    if FORCE is nonzero.  */
2774 
2775 bool
assemble_integer(rtx x,unsigned int size,unsigned int align,int force)2776 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2777 {
2778   int aligned_p;
2779 
2780   aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2781 
2782   /* See if the target hook can handle this kind of object.  */
2783   if (targetm.asm_out.integer (x, size, aligned_p))
2784     return true;
2785 
2786   /* If the object is a multi-byte one, try splitting it up.  Split
2787      it into words it if is multi-word, otherwise split it into bytes.  */
2788   if (size > 1)
2789     {
2790       machine_mode omode, imode;
2791       unsigned int subalign;
2792       unsigned int subsize, i;
2793       enum mode_class mclass;
2794 
2795       subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2796       subalign = MIN (align, subsize * BITS_PER_UNIT);
2797       if (GET_CODE (x) == CONST_FIXED)
2798 	mclass = GET_MODE_CLASS (GET_MODE (x));
2799       else
2800 	mclass = MODE_INT;
2801 
2802       omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0).require ();
2803       imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0).require ();
2804 
2805       for (i = 0; i < size; i += subsize)
2806 	{
2807 	  rtx partial = simplify_subreg (omode, x, imode, i);
2808 	  if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2809 	    break;
2810 	}
2811       if (i == size)
2812 	return true;
2813 
2814       /* If we've printed some of it, but not all of it, there's no going
2815 	 back now.  */
2816       gcc_assert (!i);
2817     }
2818 
2819   gcc_assert (!force);
2820 
2821   return false;
2822 }
2823 
2824 /* Assemble the floating-point constant D into an object of size MODE.  ALIGN
2825    is the alignment of the constant in bits.  If REVERSE is true, D is output
2826    in reverse storage order.  */
2827 
2828 void
assemble_real(REAL_VALUE_TYPE d,scalar_float_mode mode,unsigned int align,bool reverse)2829 assemble_real (REAL_VALUE_TYPE d, scalar_float_mode mode, unsigned int align,
2830 	       bool reverse)
2831 {
2832   long data[4] = {0, 0, 0, 0};
2833   int bitsize, nelts, nunits, units_per;
2834   rtx elt;
2835 
2836   /* This is hairy.  We have a quantity of known size.  real_to_target
2837      will put it into an array of *host* longs, 32 bits per element
2838      (even if long is more than 32 bits).  We need to determine the
2839      number of array elements that are occupied (nelts) and the number
2840      of *target* min-addressable units that will be occupied in the
2841      object file (nunits).  We cannot assume that 32 divides the
2842      mode's bitsize (size * BITS_PER_UNIT) evenly.
2843 
2844      size * BITS_PER_UNIT is used here to make sure that padding bits
2845      (which might appear at either end of the value; real_to_target
2846      will include the padding bits in its output array) are included.  */
2847 
2848   nunits = GET_MODE_SIZE (mode);
2849   bitsize = nunits * BITS_PER_UNIT;
2850   nelts = CEIL (bitsize, 32);
2851   units_per = 32 / BITS_PER_UNIT;
2852 
2853   real_to_target (data, &d, mode);
2854 
2855   /* Put out the first word with the specified alignment.  */
2856   if (reverse)
2857     elt = flip_storage_order (SImode, gen_int_mode (data[nelts - 1], SImode));
2858   else
2859     elt = GEN_INT (data[0]);
2860   assemble_integer (elt, MIN (nunits, units_per), align, 1);
2861   nunits -= units_per;
2862 
2863   /* Subsequent words need only 32-bit alignment.  */
2864   align = min_align (align, 32);
2865 
2866   for (int i = 1; i < nelts; i++)
2867     {
2868       if (reverse)
2869 	elt = flip_storage_order (SImode,
2870 				  gen_int_mode (data[nelts - 1 - i], SImode));
2871       else
2872 	elt = GEN_INT (data[i]);
2873       assemble_integer (elt, MIN (nunits, units_per), align, 1);
2874       nunits -= units_per;
2875     }
2876 }
2877 
2878 /* Given an expression EXP with a constant value,
2879    reduce it to the sum of an assembler symbol and an integer.
2880    Store them both in the structure *VALUE.
2881    EXP must be reducible.  */
2882 
2883 struct addr_const {
2884   rtx base;
2885   poly_int64 offset;
2886 };
2887 
2888 static void
decode_addr_const(tree exp,struct addr_const * value)2889 decode_addr_const (tree exp, struct addr_const *value)
2890 {
2891   tree target = TREE_OPERAND (exp, 0);
2892   poly_int64 offset = 0;
2893   rtx x;
2894 
2895   while (1)
2896     {
2897       poly_int64 bytepos;
2898       if (TREE_CODE (target) == COMPONENT_REF
2899 	  && poly_int_tree_p (byte_position (TREE_OPERAND (target, 1)),
2900 			      &bytepos))
2901 	{
2902 	  offset += bytepos;
2903 	  target = TREE_OPERAND (target, 0);
2904 	}
2905       else if (TREE_CODE (target) == ARRAY_REF
2906 	       || TREE_CODE (target) == ARRAY_RANGE_REF)
2907 	{
2908 	  /* Truncate big offset.  */
2909 	  offset
2910 	    += (TREE_INT_CST_LOW (TYPE_SIZE_UNIT (TREE_TYPE (target)))
2911 		* wi::to_poly_widest (TREE_OPERAND (target, 1)).force_shwi ());
2912 	  target = TREE_OPERAND (target, 0);
2913 	}
2914       else if (TREE_CODE (target) == MEM_REF
2915 	       && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR)
2916 	{
2917 	  offset += mem_ref_offset (target).force_shwi ();
2918 	  target = TREE_OPERAND (TREE_OPERAND (target, 0), 0);
2919 	}
2920       else if (TREE_CODE (target) == INDIRECT_REF
2921 	       && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR
2922 	       && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0))
2923 		  == ADDR_EXPR)
2924 	target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0);
2925       else
2926 	break;
2927     }
2928 
2929   switch (TREE_CODE (target))
2930     {
2931     case VAR_DECL:
2932     case FUNCTION_DECL:
2933       x = DECL_RTL (target);
2934       break;
2935 
2936     case LABEL_DECL:
2937       x = gen_rtx_MEM (FUNCTION_MODE,
2938 		       gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2939       break;
2940 
2941     case REAL_CST:
2942     case FIXED_CST:
2943     case STRING_CST:
2944     case COMPLEX_CST:
2945     case CONSTRUCTOR:
2946     case INTEGER_CST:
2947       x = output_constant_def (target, 1);
2948       break;
2949 
2950     case INDIRECT_REF:
2951       /* This deals with absolute addresses.  */
2952       offset += tree_to_shwi (TREE_OPERAND (target, 0));
2953       x = gen_rtx_MEM (QImode,
2954 		       gen_rtx_SYMBOL_REF (Pmode, "origin of addresses"));
2955       break;
2956 
2957     case COMPOUND_LITERAL_EXPR:
2958       gcc_assert (COMPOUND_LITERAL_EXPR_DECL (target));
2959       x = DECL_RTL (COMPOUND_LITERAL_EXPR_DECL (target));
2960       break;
2961 
2962     default:
2963       gcc_unreachable ();
2964     }
2965 
2966   gcc_assert (MEM_P (x));
2967   x = XEXP (x, 0);
2968 
2969   value->base = x;
2970   value->offset = offset;
2971 }
2972 
2973 static GTY(()) hash_table<tree_descriptor_hasher> *const_desc_htab;
2974 
2975 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2976 
2977 /* Constant pool accessor function.  */
2978 
2979 hash_table<tree_descriptor_hasher> *
constant_pool_htab(void)2980 constant_pool_htab (void)
2981 {
2982   return const_desc_htab;
2983 }
2984 
2985 /* Compute a hash code for a constant expression.  */
2986 
2987 hashval_t
hash(constant_descriptor_tree * ptr)2988 tree_descriptor_hasher::hash (constant_descriptor_tree *ptr)
2989 {
2990   return ptr->hash;
2991 }
2992 
2993 static hashval_t
const_hash_1(const tree exp)2994 const_hash_1 (const tree exp)
2995 {
2996   const char *p;
2997   hashval_t hi;
2998   int len, i;
2999   enum tree_code code = TREE_CODE (exp);
3000 
3001   /* Either set P and LEN to the address and len of something to hash and
3002      exit the switch or return a value.  */
3003 
3004   switch (code)
3005     {
3006     case INTEGER_CST:
3007       p = (char *) &TREE_INT_CST_ELT (exp, 0);
3008       len = TREE_INT_CST_NUNITS (exp) * sizeof (HOST_WIDE_INT);
3009       break;
3010 
3011     case REAL_CST:
3012       return real_hash (TREE_REAL_CST_PTR (exp));
3013 
3014     case FIXED_CST:
3015       return fixed_hash (TREE_FIXED_CST_PTR (exp));
3016 
3017     case STRING_CST:
3018       p = TREE_STRING_POINTER (exp);
3019       len = TREE_STRING_LENGTH (exp);
3020       break;
3021 
3022     case COMPLEX_CST:
3023       return (const_hash_1 (TREE_REALPART (exp)) * 5
3024 	      + const_hash_1 (TREE_IMAGPART (exp)));
3025 
3026     case VECTOR_CST:
3027       {
3028 	hi = 7 + VECTOR_CST_NPATTERNS (exp);
3029 	hi = hi * 563 + VECTOR_CST_NELTS_PER_PATTERN (exp);
3030 	unsigned int count = vector_cst_encoded_nelts (exp);
3031 	for (unsigned int i = 0; i < count; ++i)
3032 	  hi = hi * 563 + const_hash_1 (VECTOR_CST_ENCODED_ELT (exp, i));
3033 	return hi;
3034       }
3035 
3036     case CONSTRUCTOR:
3037       {
3038 	unsigned HOST_WIDE_INT idx;
3039 	tree value;
3040 
3041 	hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
3042 
3043 	FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
3044 	  if (value)
3045 	    hi = hi * 603 + const_hash_1 (value);
3046 
3047 	return hi;
3048       }
3049 
3050     case ADDR_EXPR:
3051     case FDESC_EXPR:
3052       {
3053 	struct addr_const value;
3054 
3055 	decode_addr_const (exp, &value);
3056 	switch (GET_CODE (value.base))
3057 	  {
3058 	  case SYMBOL_REF:
3059 	    /* Don't hash the address of the SYMBOL_REF;
3060 	       only use the offset and the symbol name.  */
3061 	    hi = value.offset.coeffs[0];
3062 	    p = XSTR (value.base, 0);
3063 	    for (i = 0; p[i] != 0; i++)
3064 	      hi = ((hi * 613) + (unsigned) (p[i]));
3065 	    break;
3066 
3067 	  case LABEL_REF:
3068 	    hi = (value.offset.coeffs[0]
3069 		  + CODE_LABEL_NUMBER (label_ref_label (value.base)) * 13);
3070 	    break;
3071 
3072 	  default:
3073 	    gcc_unreachable ();
3074 	  }
3075       }
3076       return hi;
3077 
3078     case PLUS_EXPR:
3079     case POINTER_PLUS_EXPR:
3080     case MINUS_EXPR:
3081       return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
3082 	      + const_hash_1 (TREE_OPERAND (exp, 1)));
3083 
3084     CASE_CONVERT:
3085       return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
3086 
3087     default:
3088       /* A language specific constant. Just hash the code.  */
3089       return code;
3090     }
3091 
3092   /* Compute hashing function.  */
3093   hi = len;
3094   for (i = 0; i < len; i++)
3095     hi = ((hi * 613) + (unsigned) (p[i]));
3096 
3097   return hi;
3098 }
3099 
3100 /* Wrapper of compare_constant, for the htab interface.  */
3101 bool
equal(constant_descriptor_tree * c1,constant_descriptor_tree * c2)3102 tree_descriptor_hasher::equal (constant_descriptor_tree *c1,
3103 			       constant_descriptor_tree *c2)
3104 {
3105   if (c1->hash != c2->hash)
3106     return 0;
3107   return compare_constant (c1->value, c2->value);
3108 }
3109 
3110 /* Compare t1 and t2, and return 1 only if they are known to result in
3111    the same bit pattern on output.  */
3112 
3113 static int
compare_constant(const tree t1,const tree t2)3114 compare_constant (const tree t1, const tree t2)
3115 {
3116   enum tree_code typecode;
3117 
3118   if (t1 == NULL_TREE)
3119     return t2 == NULL_TREE;
3120   if (t2 == NULL_TREE)
3121     return 0;
3122 
3123   if (TREE_CODE (t1) != TREE_CODE (t2))
3124     return 0;
3125 
3126   switch (TREE_CODE (t1))
3127     {
3128     case INTEGER_CST:
3129       /* Integer constants are the same only if the same width of type.  */
3130       if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3131 	return 0;
3132       if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3133 	return 0;
3134       return tree_int_cst_equal (t1, t2);
3135 
3136     case REAL_CST:
3137       /* Real constants are the same only if the same width of type.  In
3138 	 addition to the same width, we need to check whether the modes are the
3139 	 same.  There might be two floating point modes that are the same size
3140 	 but have different representations, such as the PowerPC that has 2
3141 	 different 128-bit floating point types (IBM extended double and IEEE
3142 	 128-bit floating point).  */
3143       if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3144 	return 0;
3145       if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3146 	return 0;
3147       return real_identical (&TREE_REAL_CST (t1), &TREE_REAL_CST (t2));
3148 
3149     case FIXED_CST:
3150       /* Fixed constants are the same only if the same width of type.  */
3151       if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3152 	return 0;
3153 
3154       return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
3155 
3156     case STRING_CST:
3157       if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3158 	return 0;
3159 
3160       return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
3161 	      && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
3162 			 TREE_STRING_LENGTH (t1)));
3163 
3164     case COMPLEX_CST:
3165       return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
3166 	      && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
3167 
3168     case VECTOR_CST:
3169       {
3170 	if (VECTOR_CST_NPATTERNS (t1)
3171 	    != VECTOR_CST_NPATTERNS (t2))
3172 	  return 0;
3173 
3174 	if (VECTOR_CST_NELTS_PER_PATTERN (t1)
3175 	    != VECTOR_CST_NELTS_PER_PATTERN (t2))
3176 	  return 0;
3177 
3178 	unsigned int count = vector_cst_encoded_nelts (t1);
3179 	for (unsigned int i = 0; i < count; ++i)
3180 	  if (!compare_constant (VECTOR_CST_ENCODED_ELT (t1, i),
3181 				 VECTOR_CST_ENCODED_ELT (t2, i)))
3182 	    return 0;
3183 
3184 	return 1;
3185       }
3186 
3187     case CONSTRUCTOR:
3188       {
3189 	vec<constructor_elt, va_gc> *v1, *v2;
3190 	unsigned HOST_WIDE_INT idx;
3191 
3192 	typecode = TREE_CODE (TREE_TYPE (t1));
3193 	if (typecode != TREE_CODE (TREE_TYPE (t2)))
3194 	  return 0;
3195 
3196 	if (typecode == ARRAY_TYPE)
3197 	  {
3198 	    HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
3199 	    /* For arrays, check that mode, size and storage order match.  */
3200 	    if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
3201 		|| size_1 == -1
3202 		|| size_1 != int_size_in_bytes (TREE_TYPE (t2))
3203 		|| TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (t1))
3204 		   != TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (t2)))
3205 	      return 0;
3206 	  }
3207 	else
3208 	  {
3209 	    /* For record and union constructors, require exact type
3210                equality.  */
3211 	    if (TREE_TYPE (t1) != TREE_TYPE (t2))
3212 	      return 0;
3213 	  }
3214 
3215 	v1 = CONSTRUCTOR_ELTS (t1);
3216 	v2 = CONSTRUCTOR_ELTS (t2);
3217 	if (vec_safe_length (v1) != vec_safe_length (v2))
3218 	  return 0;
3219 
3220 	for (idx = 0; idx < vec_safe_length (v1); ++idx)
3221 	  {
3222 	    constructor_elt *c1 = &(*v1)[idx];
3223 	    constructor_elt *c2 = &(*v2)[idx];
3224 
3225 	    /* Check that each value is the same...  */
3226 	    if (!compare_constant (c1->value, c2->value))
3227 	      return 0;
3228 	    /* ... and that they apply to the same fields!  */
3229 	    if (typecode == ARRAY_TYPE)
3230 	      {
3231 		if (!compare_constant (c1->index, c2->index))
3232 		  return 0;
3233 	      }
3234 	    else
3235 	      {
3236 		if (c1->index != c2->index)
3237 		  return 0;
3238 	      }
3239 	  }
3240 
3241 	return 1;
3242       }
3243 
3244     case ADDR_EXPR:
3245     case FDESC_EXPR:
3246       {
3247 	struct addr_const value1, value2;
3248 	enum rtx_code code;
3249 	int ret;
3250 
3251 	decode_addr_const (t1, &value1);
3252 	decode_addr_const (t2, &value2);
3253 
3254 	if (maybe_ne (value1.offset, value2.offset))
3255 	  return 0;
3256 
3257 	code = GET_CODE (value1.base);
3258 	if (code != GET_CODE (value2.base))
3259 	  return 0;
3260 
3261 	switch (code)
3262 	  {
3263 	  case SYMBOL_REF:
3264 	    ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3265 	    break;
3266 
3267 	  case LABEL_REF:
3268 	    ret = (CODE_LABEL_NUMBER (label_ref_label (value1.base))
3269 		   == CODE_LABEL_NUMBER (label_ref_label (value2.base)));
3270 	    break;
3271 
3272 	  default:
3273 	    gcc_unreachable ();
3274 	  }
3275 	return ret;
3276       }
3277 
3278     case PLUS_EXPR:
3279     case POINTER_PLUS_EXPR:
3280     case MINUS_EXPR:
3281     case RANGE_EXPR:
3282       return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3283 	      && compare_constant (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3284 
3285     CASE_CONVERT:
3286     case VIEW_CONVERT_EXPR:
3287       return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3288 
3289     default:
3290       return 0;
3291     }
3292 
3293   gcc_unreachable ();
3294 }
3295 
3296 /* Return the section into which constant EXP should be placed.  */
3297 
3298 static section *
get_constant_section(tree exp,unsigned int align)3299 get_constant_section (tree exp, unsigned int align)
3300 {
3301   return targetm.asm_out.select_section (exp,
3302 					 compute_reloc_for_constant (exp),
3303 					 align);
3304 }
3305 
3306 /* Return the size of constant EXP in bytes.  */
3307 
3308 static HOST_WIDE_INT
get_constant_size(tree exp)3309 get_constant_size (tree exp)
3310 {
3311   HOST_WIDE_INT size;
3312 
3313   size = int_size_in_bytes (TREE_TYPE (exp));
3314   if (TREE_CODE (exp) == STRING_CST)
3315     size = MAX (TREE_STRING_LENGTH (exp), size);
3316   return size;
3317 }
3318 
3319 /* Subroutine of output_constant_def:
3320    No constant equal to EXP is known to have been output.
3321    Make a constant descriptor to enter EXP in the hash table.
3322    Assign the label number and construct RTL to refer to the
3323    constant's location in memory.
3324    Caller is responsible for updating the hash table.  */
3325 
3326 static struct constant_descriptor_tree *
build_constant_desc(tree exp)3327 build_constant_desc (tree exp)
3328 {
3329   struct constant_descriptor_tree *desc;
3330   rtx symbol, rtl;
3331   char label[256];
3332   int labelno;
3333   tree decl;
3334 
3335   desc = ggc_alloc<constant_descriptor_tree> ();
3336   desc->value = exp;
3337 
3338   /* Create a string containing the label name, in LABEL.  */
3339   labelno = const_labelno++;
3340   ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3341 
3342   /* Construct the VAR_DECL associated with the constant.  */
3343   decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3344 		     TREE_TYPE (exp));
3345   DECL_ARTIFICIAL (decl) = 1;
3346   DECL_IGNORED_P (decl) = 1;
3347   TREE_READONLY (decl) = 1;
3348   TREE_STATIC (decl) = 1;
3349   TREE_ADDRESSABLE (decl) = 1;
3350   /* We don't set the RTL yet as this would cause varpool to assume that the
3351      variable is referenced.  Moreover, it would just be dropped in LTO mode.
3352      Instead we set the flag that will be recognized in make_decl_rtl.  */
3353   DECL_IN_CONSTANT_POOL (decl) = 1;
3354   DECL_INITIAL (decl) = desc->value;
3355   /* ??? targetm.constant_alignment hasn't been updated for vector types on
3356      most architectures so use DATA_ALIGNMENT as well, except for strings.  */
3357   if (TREE_CODE (exp) == STRING_CST)
3358     SET_DECL_ALIGN (decl, targetm.constant_alignment (exp, DECL_ALIGN (decl)));
3359   else
3360     align_variable (decl, 0);
3361 
3362   /* Now construct the SYMBOL_REF and the MEM.  */
3363   if (use_object_blocks_p ())
3364     {
3365       int align = (TREE_CODE (decl) == CONST_DECL
3366 		   || (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
3367 		   ? DECL_ALIGN (decl)
3368 		   : symtab_node::get (decl)->definition_alignment ());
3369       section *sect = get_constant_section (exp, align);
3370       symbol = create_block_symbol (ggc_strdup (label),
3371 				    get_block_for_section (sect), -1);
3372     }
3373   else
3374     symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3375   SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3376   SET_SYMBOL_REF_DECL (symbol, decl);
3377   TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3378 
3379   rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3380   set_mem_attributes (rtl, exp, 1);
3381   set_mem_alias_set (rtl, 0);
3382 
3383   /* Putting EXP into the literal pool might have imposed a different
3384      alignment which should be visible in the RTX as well.  */
3385   set_mem_align (rtl, DECL_ALIGN (decl));
3386 
3387   /* We cannot share RTX'es in pool entries.
3388      Mark this piece of RTL as required for unsharing.  */
3389   RTX_FLAG (rtl, used) = 1;
3390 
3391   /* Set flags or add text to the name to record information, such as
3392      that it is a local symbol.  If the name is changed, the macro
3393      ASM_OUTPUT_LABELREF will have to know how to strip this
3394      information.  This call might invalidate our local variable
3395      SYMBOL; we can't use it afterward.  */
3396   targetm.encode_section_info (exp, rtl, true);
3397 
3398   desc->rtl = rtl;
3399 
3400   return desc;
3401 }
3402 
3403 /* Return an rtx representing a reference to constant data in memory
3404    for the constant expression EXP.
3405 
3406    If assembler code for such a constant has already been output,
3407    return an rtx to refer to it.
3408    Otherwise, output such a constant in memory
3409    and generate an rtx for it.
3410 
3411    If DEFER is nonzero, this constant can be deferred and output only
3412    if referenced in the function after all optimizations.
3413 
3414    `const_desc_table' records which constants already have label strings.  */
3415 
3416 rtx
output_constant_def(tree exp,int defer)3417 output_constant_def (tree exp, int defer)
3418 {
3419   struct constant_descriptor_tree *desc;
3420   struct constant_descriptor_tree key;
3421 
3422   /* Look up EXP in the table of constant descriptors.  If we didn't find
3423      it, create a new one.  */
3424   key.value = exp;
3425   key.hash = const_hash_1 (exp);
3426   constant_descriptor_tree **loc
3427     = const_desc_htab->find_slot_with_hash (&key, key.hash, INSERT);
3428 
3429   desc = *loc;
3430   if (desc == 0)
3431     {
3432       desc = build_constant_desc (exp);
3433       desc->hash = key.hash;
3434       *loc = desc;
3435     }
3436 
3437   maybe_output_constant_def_contents (desc, defer);
3438   return desc->rtl;
3439 }
3440 
3441 /* Subroutine of output_constant_def: Decide whether or not we need to
3442    output the constant DESC now, and if so, do it.  */
3443 static void
maybe_output_constant_def_contents(struct constant_descriptor_tree * desc,int defer)3444 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3445 				    int defer)
3446 {
3447   rtx symbol = XEXP (desc->rtl, 0);
3448   tree exp = desc->value;
3449 
3450   if (flag_syntax_only)
3451     return;
3452 
3453   if (TREE_ASM_WRITTEN (exp))
3454     /* Already output; don't do it again.  */
3455     return;
3456 
3457   /* We can always defer constants as long as the context allows
3458      doing so.  */
3459   if (defer)
3460     {
3461       /* Increment n_deferred_constants if it exists.  It needs to be at
3462 	 least as large as the number of constants actually referred to
3463 	 by the function.  If it's too small we'll stop looking too early
3464 	 and fail to emit constants; if it's too large we'll only look
3465 	 through the entire function when we could have stopped earlier.  */
3466       if (cfun)
3467 	n_deferred_constants++;
3468       return;
3469     }
3470 
3471   output_constant_def_contents (symbol);
3472 }
3473 
3474 /* Subroutine of output_constant_def_contents.  Output the definition
3475    of constant EXP, which is pointed to by label LABEL.  ALIGN is the
3476    constant's alignment in bits.  */
3477 
3478 static void
assemble_constant_contents(tree exp,const char * label,unsigned int align)3479 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3480 {
3481   HOST_WIDE_INT size;
3482 
3483   size = get_constant_size (exp);
3484 
3485   /* Do any machine/system dependent processing of the constant.  */
3486   targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3487 
3488   /* Output the value of EXP.  */
3489   output_constant (exp, size, align, false);
3490 
3491   targetm.asm_out.decl_end ();
3492 }
3493 
3494 /* We must output the constant data referred to by SYMBOL; do so.  */
3495 
3496 static void
output_constant_def_contents(rtx symbol)3497 output_constant_def_contents (rtx symbol)
3498 {
3499   tree decl = SYMBOL_REF_DECL (symbol);
3500   tree exp = DECL_INITIAL (decl);
3501   bool asan_protected = false;
3502 
3503   /* Make sure any other constants whose addresses appear in EXP
3504      are assigned label numbers.  */
3505   output_addressed_constants (exp);
3506 
3507   /* We are no longer deferring this constant.  */
3508   TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3509 
3510   if ((flag_sanitize & SANITIZE_ADDRESS)
3511       && TREE_CODE (exp) == STRING_CST
3512       && asan_protect_global (exp))
3513     {
3514       asan_protected = true;
3515       SET_DECL_ALIGN (decl, MAX (DECL_ALIGN (decl),
3516 				 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT));
3517     }
3518 
3519   /* If the constant is part of an object block, make sure that the
3520      decl has been positioned within its block, but do not write out
3521      its definition yet.  output_object_blocks will do that later.  */
3522   if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3523     place_block_symbol (symbol);
3524   else
3525     {
3526       int align = (TREE_CODE (decl) == CONST_DECL
3527 		   || (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
3528 		   ? DECL_ALIGN (decl)
3529 		   : symtab_node::get (decl)->definition_alignment ());
3530       switch_to_section (get_constant_section (exp, align));
3531       if (align > BITS_PER_UNIT)
3532 	ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3533       assemble_constant_contents (exp, XSTR (symbol, 0), align);
3534       if (asan_protected)
3535 	{
3536 	  HOST_WIDE_INT size = get_constant_size (exp);
3537 	  assemble_zeros (asan_red_zone_size (size));
3538 	}
3539     }
3540 }
3541 
3542 /* Look up EXP in the table of constant descriptors.  Return the rtl
3543    if it has been emitted, else null.  */
3544 
3545 rtx
lookup_constant_def(tree exp)3546 lookup_constant_def (tree exp)
3547 {
3548   struct constant_descriptor_tree key;
3549 
3550   key.value = exp;
3551   key.hash = const_hash_1 (exp);
3552   constant_descriptor_tree *desc
3553     = const_desc_htab->find_with_hash (&key, key.hash);
3554 
3555   return (desc ? desc->rtl : NULL_RTX);
3556 }
3557 
3558 /* Return a tree representing a reference to constant data in memory
3559    for the constant expression EXP.
3560 
3561    This is the counterpart of output_constant_def at the Tree level.  */
3562 
3563 tree
tree_output_constant_def(tree exp)3564 tree_output_constant_def (tree exp)
3565 {
3566   struct constant_descriptor_tree *desc, key;
3567   tree decl;
3568 
3569   /* Look up EXP in the table of constant descriptors.  If we didn't find
3570      it, create a new one.  */
3571   key.value = exp;
3572   key.hash = const_hash_1 (exp);
3573   constant_descriptor_tree **loc
3574     = const_desc_htab->find_slot_with_hash (&key, key.hash, INSERT);
3575 
3576   desc = *loc;
3577   if (desc == 0)
3578     {
3579       desc = build_constant_desc (exp);
3580       desc->hash = key.hash;
3581       *loc = desc;
3582     }
3583 
3584   decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3585   varpool_node::finalize_decl (decl);
3586   return decl;
3587 }
3588 
3589 struct GTY((chain_next ("%h.next"), for_user)) constant_descriptor_rtx {
3590   struct constant_descriptor_rtx *next;
3591   rtx mem;
3592   rtx sym;
3593   rtx constant;
3594   HOST_WIDE_INT offset;
3595   hashval_t hash;
3596   fixed_size_mode mode;
3597   unsigned int align;
3598   int labelno;
3599   int mark;
3600 };
3601 
3602 struct const_rtx_desc_hasher : ggc_ptr_hash<constant_descriptor_rtx>
3603 {
3604   static hashval_t hash (constant_descriptor_rtx *);
3605   static bool equal (constant_descriptor_rtx *, constant_descriptor_rtx *);
3606 };
3607 
3608 /* Used in the hash tables to avoid outputting the same constant
3609    twice.  Unlike 'struct constant_descriptor_tree', RTX constants
3610    are output once per function, not once per file.  */
3611 /* ??? Only a few targets need per-function constant pools.  Most
3612    can use one per-file pool.  Should add a targetm bit to tell the
3613    difference.  */
3614 
3615 struct GTY(()) rtx_constant_pool {
3616   /* Pointers to first and last constant in pool, as ordered by offset.  */
3617   struct constant_descriptor_rtx *first;
3618   struct constant_descriptor_rtx *last;
3619 
3620   /* Hash facility for making memory-constants from constant rtl-expressions.
3621      It is used on RISC machines where immediate integer arguments and
3622      constant addresses are restricted so that such constants must be stored
3623      in memory.  */
3624   hash_table<const_rtx_desc_hasher> *const_rtx_htab;
3625 
3626   /* Current offset in constant pool (does not include any
3627      machine-specific header).  */
3628   HOST_WIDE_INT offset;
3629 };
3630 
3631 /* Hash and compare functions for const_rtx_htab.  */
3632 
3633 hashval_t
hash(constant_descriptor_rtx * desc)3634 const_rtx_desc_hasher::hash (constant_descriptor_rtx *desc)
3635 {
3636   return desc->hash;
3637 }
3638 
3639 bool
equal(constant_descriptor_rtx * x,constant_descriptor_rtx * y)3640 const_rtx_desc_hasher::equal (constant_descriptor_rtx *x,
3641 			      constant_descriptor_rtx *y)
3642 {
3643   if (x->mode != y->mode)
3644     return 0;
3645   return rtx_equal_p (x->constant, y->constant);
3646 }
3647 
3648 /* Hash one component of a constant.  */
3649 
3650 static hashval_t
const_rtx_hash_1(const_rtx x)3651 const_rtx_hash_1 (const_rtx x)
3652 {
3653   unsigned HOST_WIDE_INT hwi;
3654   machine_mode mode;
3655   enum rtx_code code;
3656   hashval_t h;
3657   int i;
3658 
3659   code = GET_CODE (x);
3660   mode = GET_MODE (x);
3661   h = (hashval_t) code * 1048573 + mode;
3662 
3663   switch (code)
3664     {
3665     case CONST_INT:
3666       hwi = INTVAL (x);
3667 
3668     fold_hwi:
3669       {
3670 	int shift = sizeof (hashval_t) * CHAR_BIT;
3671 	const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3672 
3673 	h ^= (hashval_t) hwi;
3674 	for (i = 1; i < n; ++i)
3675 	  {
3676 	    hwi >>= shift;
3677 	    h ^= (hashval_t) hwi;
3678 	  }
3679       }
3680       break;
3681 
3682     case CONST_WIDE_INT:
3683       hwi = 0;
3684       {
3685 	for (i = 0; i < CONST_WIDE_INT_NUNITS (x); i++)
3686 	  hwi ^= CONST_WIDE_INT_ELT (x, i);
3687 	goto fold_hwi;
3688       }
3689 
3690     case CONST_DOUBLE:
3691       if (TARGET_SUPPORTS_WIDE_INT == 0 && mode == VOIDmode)
3692 	{
3693 	  hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3694 	  goto fold_hwi;
3695 	}
3696       else
3697 	h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3698       break;
3699 
3700     case CONST_FIXED:
3701       h ^= fixed_hash (CONST_FIXED_VALUE (x));
3702       break;
3703 
3704     case SYMBOL_REF:
3705       h ^= htab_hash_string (XSTR (x, 0));
3706       break;
3707 
3708     case LABEL_REF:
3709       h = h * 251 + CODE_LABEL_NUMBER (label_ref_label (x));
3710       break;
3711 
3712     case UNSPEC:
3713     case UNSPEC_VOLATILE:
3714       h = h * 251 + XINT (x, 1);
3715       break;
3716 
3717     default:
3718       break;
3719     }
3720 
3721   return h;
3722 }
3723 
3724 /* Compute a hash value for X, which should be a constant.  */
3725 
3726 static hashval_t
const_rtx_hash(rtx x)3727 const_rtx_hash (rtx x)
3728 {
3729   hashval_t h = 0;
3730   subrtx_iterator::array_type array;
3731   FOR_EACH_SUBRTX (iter, array, x, ALL)
3732     h = h * 509 + const_rtx_hash_1 (*iter);
3733   return h;
3734 }
3735 
3736 
3737 /* Create and return a new rtx constant pool.  */
3738 
3739 static struct rtx_constant_pool *
create_constant_pool(void)3740 create_constant_pool (void)
3741 {
3742   struct rtx_constant_pool *pool;
3743 
3744   pool = ggc_alloc<rtx_constant_pool> ();
3745   pool->const_rtx_htab = hash_table<const_rtx_desc_hasher>::create_ggc (31);
3746   pool->first = NULL;
3747   pool->last = NULL;
3748   pool->offset = 0;
3749   return pool;
3750 }
3751 
3752 /* Initialize constant pool hashing for a new function.  */
3753 
3754 void
init_varasm_status(void)3755 init_varasm_status (void)
3756 {
3757   crtl->varasm.pool = create_constant_pool ();
3758   crtl->varasm.deferred_constants = 0;
3759 }
3760 
3761 /* Given a MINUS expression, simplify it if both sides
3762    include the same symbol.  */
3763 
3764 rtx
simplify_subtraction(rtx x)3765 simplify_subtraction (rtx x)
3766 {
3767   rtx r = simplify_rtx (x);
3768   return r ? r : x;
3769 }
3770 
3771 /* Given a constant rtx X, make (or find) a memory constant for its value
3772    and return a MEM rtx to refer to it in memory.  IN_MODE is the mode
3773    of X.  */
3774 
3775 rtx
force_const_mem(machine_mode in_mode,rtx x)3776 force_const_mem (machine_mode in_mode, rtx x)
3777 {
3778   struct constant_descriptor_rtx *desc, tmp;
3779   struct rtx_constant_pool *pool;
3780   char label[256];
3781   rtx def, symbol;
3782   hashval_t hash;
3783   unsigned int align;
3784   constant_descriptor_rtx **slot;
3785   fixed_size_mode mode;
3786 
3787   /* We can't force variable-sized objects to memory.  */
3788   if (!is_a <fixed_size_mode> (in_mode, &mode))
3789     return NULL_RTX;
3790 
3791   /* If we're not allowed to drop X into the constant pool, don't.  */
3792   if (targetm.cannot_force_const_mem (mode, x))
3793     return NULL_RTX;
3794 
3795   /* Record that this function has used a constant pool entry.  */
3796   crtl->uses_const_pool = 1;
3797 
3798   /* Decide which pool to use.  */
3799   pool = (targetm.use_blocks_for_constant_p (mode, x)
3800 	  ? shared_constant_pool
3801 	  : crtl->varasm.pool);
3802 
3803   /* Lookup the value in the hashtable.  */
3804   tmp.constant = x;
3805   tmp.mode = mode;
3806   hash = const_rtx_hash (x);
3807   slot = pool->const_rtx_htab->find_slot_with_hash (&tmp, hash, INSERT);
3808   desc = *slot;
3809 
3810   /* If the constant was already present, return its memory.  */
3811   if (desc)
3812     return copy_rtx (desc->mem);
3813 
3814   /* Otherwise, create a new descriptor.  */
3815   desc = ggc_alloc<constant_descriptor_rtx> ();
3816   *slot = desc;
3817 
3818   /* Align the location counter as required by EXP's data type.  */
3819   machine_mode align_mode = (mode == VOIDmode ? word_mode : mode);
3820   align = targetm.static_rtx_alignment (align_mode);
3821 
3822   pool->offset += (align / BITS_PER_UNIT) - 1;
3823   pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3824 
3825   desc->next = NULL;
3826   desc->constant = copy_rtx (tmp.constant);
3827   desc->offset = pool->offset;
3828   desc->hash = hash;
3829   desc->mode = mode;
3830   desc->align = align;
3831   desc->labelno = const_labelno;
3832   desc->mark = 0;
3833 
3834   pool->offset += GET_MODE_SIZE (mode);
3835   if (pool->last)
3836     pool->last->next = desc;
3837   else
3838     pool->first = pool->last = desc;
3839   pool->last = desc;
3840 
3841   /* Create a string containing the label name, in LABEL.  */
3842   ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3843   ++const_labelno;
3844 
3845   /* Construct the SYMBOL_REF.  Make sure to mark it as belonging to
3846      the constants pool.  */
3847   if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3848     {
3849       section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3850       symbol = create_block_symbol (ggc_strdup (label),
3851 				    get_block_for_section (sect), -1);
3852     }
3853   else
3854     symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3855   desc->sym = symbol;
3856   SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3857   CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3858   SET_SYMBOL_REF_CONSTANT (symbol, desc);
3859 
3860   /* Construct the MEM.  */
3861   desc->mem = def = gen_const_mem (mode, symbol);
3862   set_mem_align (def, align);
3863 
3864   /* If we're dropping a label to the constant pool, make sure we
3865      don't delete it.  */
3866   if (GET_CODE (x) == LABEL_REF)
3867     LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3868 
3869   return copy_rtx (def);
3870 }
3871 
3872 /* Given a constant pool SYMBOL_REF, return the corresponding constant.  */
3873 
3874 rtx
get_pool_constant(const_rtx addr)3875 get_pool_constant (const_rtx addr)
3876 {
3877   return SYMBOL_REF_CONSTANT (addr)->constant;
3878 }
3879 
3880 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3881    and whether it has been output or not.  */
3882 
3883 rtx
get_pool_constant_mark(rtx addr,bool * pmarked)3884 get_pool_constant_mark (rtx addr, bool *pmarked)
3885 {
3886   struct constant_descriptor_rtx *desc;
3887 
3888   desc = SYMBOL_REF_CONSTANT (addr);
3889   *pmarked = (desc->mark != 0);
3890   return desc->constant;
3891 }
3892 
3893 /* Similar, return the mode.  */
3894 
3895 fixed_size_mode
get_pool_mode(const_rtx addr)3896 get_pool_mode (const_rtx addr)
3897 {
3898   return SYMBOL_REF_CONSTANT (addr)->mode;
3899 }
3900 
3901 /* Return TRUE if and only if the constant pool has no entries.  Note
3902    that even entries we might end up choosing not to emit are counted
3903    here, so there is the potential for missed optimizations.  */
3904 
3905 bool
constant_pool_empty_p(void)3906 constant_pool_empty_p (void)
3907 {
3908   return crtl->varasm.pool->first == NULL;
3909 }
3910 
3911 /* Worker function for output_constant_pool_1.  Emit assembly for X
3912    in MODE with known alignment ALIGN.  */
3913 
3914 static void
output_constant_pool_2(fixed_size_mode mode,rtx x,unsigned int align)3915 output_constant_pool_2 (fixed_size_mode mode, rtx x, unsigned int align)
3916 {
3917   switch (GET_MODE_CLASS (mode))
3918     {
3919     case MODE_FLOAT:
3920     case MODE_DECIMAL_FLOAT:
3921       {
3922 	gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3923 	assemble_real (*CONST_DOUBLE_REAL_VALUE (x),
3924 		       as_a <scalar_float_mode> (mode), align, false);
3925 	break;
3926       }
3927 
3928     case MODE_INT:
3929     case MODE_PARTIAL_INT:
3930     case MODE_FRACT:
3931     case MODE_UFRACT:
3932     case MODE_ACCUM:
3933     case MODE_UACCUM:
3934     case MODE_POINTER_BOUNDS:
3935       assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3936       break;
3937 
3938     case MODE_VECTOR_BOOL:
3939       {
3940 	gcc_assert (GET_CODE (x) == CONST_VECTOR);
3941 
3942 	/* Pick the smallest integer mode that contains at least one
3943 	   whole element.  Often this is byte_mode and contains more
3944 	   than one element.  */
3945 	unsigned int nelts = GET_MODE_NUNITS (mode);
3946 	unsigned int elt_bits = GET_MODE_BITSIZE (mode) / nelts;
3947 	unsigned int int_bits = MAX (elt_bits, BITS_PER_UNIT);
3948 	scalar_int_mode int_mode = int_mode_for_size (int_bits, 0).require ();
3949 
3950 	/* Build the constant up one integer at a time.  */
3951 	unsigned int elts_per_int = int_bits / elt_bits;
3952 	for (unsigned int i = 0; i < nelts; i += elts_per_int)
3953 	  {
3954 	    unsigned HOST_WIDE_INT value = 0;
3955 	    unsigned int limit = MIN (nelts - i, elts_per_int);
3956 	    for (unsigned int j = 0; j < limit; ++j)
3957 	      if (INTVAL (CONST_VECTOR_ELT (x, i + j)) != 0)
3958 		value |= 1 << (j * elt_bits);
3959 	    output_constant_pool_2 (int_mode, gen_int_mode (value, int_mode),
3960 				    i != 0 ? MIN (align, int_bits) : align);
3961 	  }
3962 	break;
3963       }
3964     case MODE_VECTOR_FLOAT:
3965     case MODE_VECTOR_INT:
3966     case MODE_VECTOR_FRACT:
3967     case MODE_VECTOR_UFRACT:
3968     case MODE_VECTOR_ACCUM:
3969     case MODE_VECTOR_UACCUM:
3970       {
3971 	int i, units;
3972 	scalar_mode submode = GET_MODE_INNER (mode);
3973 	unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3974 
3975 	gcc_assert (GET_CODE (x) == CONST_VECTOR);
3976 	units = GET_MODE_NUNITS (mode);
3977 
3978 	for (i = 0; i < units; i++)
3979 	  {
3980 	    rtx elt = CONST_VECTOR_ELT (x, i);
3981 	    output_constant_pool_2 (submode, elt, i ? subalign : align);
3982 	  }
3983       }
3984       break;
3985 
3986     default:
3987       gcc_unreachable ();
3988     }
3989 }
3990 
3991 /* Worker function for output_constant_pool.  Emit constant DESC,
3992    giving it ALIGN bits of alignment.  */
3993 
3994 static void
output_constant_pool_1(struct constant_descriptor_rtx * desc,unsigned int align)3995 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3996 			unsigned int align)
3997 {
3998   rtx x, tmp;
3999 
4000   x = desc->constant;
4001 
4002   /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
4003      whose CODE_LABEL has been deleted.  This can occur if a jump table
4004      is eliminated by optimization.  If so, write a constant of zero
4005      instead.  Note that this can also happen by turning the
4006      CODE_LABEL into a NOTE.  */
4007   /* ??? This seems completely and utterly wrong.  Certainly it's
4008      not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
4009      functioning even with rtx_insn::deleted and friends.  */
4010 
4011   tmp = x;
4012   switch (GET_CODE (tmp))
4013     {
4014     case CONST:
4015       if (GET_CODE (XEXP (tmp, 0)) != PLUS
4016 	  || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
4017 	break;
4018       tmp = XEXP (XEXP (tmp, 0), 0);
4019       /* FALLTHRU  */
4020 
4021     case LABEL_REF:
4022       {
4023 	rtx_insn *insn = label_ref_label (tmp);
4024 	gcc_assert (!insn->deleted ());
4025 	gcc_assert (!NOTE_P (insn)
4026 		    || NOTE_KIND (insn) != NOTE_INSN_DELETED);
4027 	break;
4028       }
4029 
4030     default:
4031       break;
4032     }
4033 
4034 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
4035   ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
4036 				 align, desc->labelno, done);
4037 #endif
4038 
4039   assemble_align (align);
4040 
4041   /* Output the label.  */
4042   targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
4043 
4044   /* Output the data.
4045      Pass actual alignment value while emitting string constant to asm code
4046      as function 'output_constant_pool_1' explicitly passes the alignment as 1
4047      assuming that the data is already aligned which prevents the generation
4048      of fix-up table entries.  */
4049   output_constant_pool_2 (desc->mode, x, desc->align);
4050 
4051   /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
4052      sections have proper size.  */
4053   if (align > GET_MODE_BITSIZE (desc->mode)
4054       && in_section
4055       && (in_section->common.flags & SECTION_MERGE))
4056     assemble_align (align);
4057 
4058 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
4059  done:
4060 #endif
4061   return;
4062 }
4063 
4064 /* Recompute the offsets of entries in POOL, and the overall size of
4065    POOL.  Do this after calling mark_constant_pool to ensure that we
4066    are computing the offset values for the pool which we will actually
4067    emit.  */
4068 
4069 static void
recompute_pool_offsets(struct rtx_constant_pool * pool)4070 recompute_pool_offsets (struct rtx_constant_pool *pool)
4071 {
4072   struct constant_descriptor_rtx *desc;
4073   pool->offset = 0;
4074 
4075   for (desc = pool->first; desc ; desc = desc->next)
4076     if (desc->mark)
4077       {
4078 	  /* Recalculate offset.  */
4079 	unsigned int align = desc->align;
4080 	pool->offset += (align / BITS_PER_UNIT) - 1;
4081 	pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
4082 	desc->offset = pool->offset;
4083 	pool->offset += GET_MODE_SIZE (desc->mode);
4084       }
4085 }
4086 
4087 /* Mark all constants that are referenced by SYMBOL_REFs in X.
4088    Emit referenced deferred strings.  */
4089 
4090 static void
mark_constants_in_pattern(rtx insn)4091 mark_constants_in_pattern (rtx insn)
4092 {
4093   subrtx_iterator::array_type array;
4094   FOR_EACH_SUBRTX (iter, array, PATTERN (insn), ALL)
4095     {
4096       const_rtx x = *iter;
4097       if (GET_CODE (x) == SYMBOL_REF)
4098 	{
4099 	  if (CONSTANT_POOL_ADDRESS_P (x))
4100 	    {
4101 	      struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
4102 	      if (desc->mark == 0)
4103 		{
4104 		  desc->mark = 1;
4105 		  iter.substitute (desc->constant);
4106 		}
4107 	    }
4108 	  else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
4109 	    {
4110 	      tree decl = SYMBOL_REF_DECL (x);
4111 	      if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
4112 		{
4113 		  n_deferred_constants--;
4114 		  output_constant_def_contents (CONST_CAST_RTX (x));
4115 		}
4116 	    }
4117 	}
4118     }
4119 }
4120 
4121 /* Look through appropriate parts of INSN, marking all entries in the
4122    constant pool which are actually being used.  Entries that are only
4123    referenced by other constants are also marked as used.  Emit
4124    deferred strings that are used.  */
4125 
4126 static void
mark_constants(rtx_insn * insn)4127 mark_constants (rtx_insn *insn)
4128 {
4129   if (!INSN_P (insn))
4130     return;
4131 
4132   /* Insns may appear inside a SEQUENCE.  Only check the patterns of
4133      insns, not any notes that may be attached.  We don't want to mark
4134      a constant just because it happens to appear in a REG_EQUIV note.  */
4135   if (rtx_sequence *seq = dyn_cast <rtx_sequence *> (PATTERN (insn)))
4136     {
4137       int i, n = seq->len ();
4138       for (i = 0; i < n; ++i)
4139 	{
4140 	  rtx subinsn = seq->element (i);
4141 	  if (INSN_P (subinsn))
4142 	    mark_constants_in_pattern (subinsn);
4143 	}
4144     }
4145   else
4146     mark_constants_in_pattern (insn);
4147 }
4148 
4149 /* Look through the instructions for this function, and mark all the
4150    entries in POOL which are actually being used.  Emit deferred constants
4151    which have indeed been used.  */
4152 
4153 static void
mark_constant_pool(void)4154 mark_constant_pool (void)
4155 {
4156   rtx_insn *insn;
4157 
4158   if (!crtl->uses_const_pool && n_deferred_constants == 0)
4159     return;
4160 
4161   for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4162     mark_constants (insn);
4163 }
4164 
4165 /* Write all the constants in POOL.  */
4166 
4167 static void
output_constant_pool_contents(struct rtx_constant_pool * pool)4168 output_constant_pool_contents (struct rtx_constant_pool *pool)
4169 {
4170   struct constant_descriptor_rtx *desc;
4171 
4172   for (desc = pool->first; desc ; desc = desc->next)
4173     if (desc->mark)
4174       {
4175 	/* If the constant is part of an object_block, make sure that
4176 	   the constant has been positioned within its block, but do not
4177 	   write out its definition yet.  output_object_blocks will do
4178 	   that later.  */
4179 	if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
4180 	    && SYMBOL_REF_BLOCK (desc->sym))
4181 	  place_block_symbol (desc->sym);
4182 	else
4183 	  {
4184 	    switch_to_section (targetm.asm_out.select_rtx_section
4185 			       (desc->mode, desc->constant, desc->align));
4186 	    output_constant_pool_1 (desc, desc->align);
4187 	  }
4188       }
4189 }
4190 
4191 /* Mark all constants that are used in the current function, then write
4192    out the function's private constant pool.  */
4193 
4194 static void
output_constant_pool(const char * fnname ATTRIBUTE_UNUSED,tree fndecl ATTRIBUTE_UNUSED)4195 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
4196 		      tree fndecl ATTRIBUTE_UNUSED)
4197 {
4198   struct rtx_constant_pool *pool = crtl->varasm.pool;
4199 
4200   /* It is possible for gcc to call force_const_mem and then to later
4201      discard the instructions which refer to the constant.  In such a
4202      case we do not need to output the constant.  */
4203   mark_constant_pool ();
4204 
4205   /* Having marked the constant pool entries we'll actually emit, we
4206      now need to rebuild the offset information, which may have become
4207      stale.  */
4208   recompute_pool_offsets (pool);
4209 
4210 #ifdef ASM_OUTPUT_POOL_PROLOGUE
4211   ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
4212 #endif
4213 
4214   output_constant_pool_contents (pool);
4215 
4216 #ifdef ASM_OUTPUT_POOL_EPILOGUE
4217   ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
4218 #endif
4219 }
4220 
4221 /* Write the contents of the shared constant pool.  */
4222 
4223 void
output_shared_constant_pool(void)4224 output_shared_constant_pool (void)
4225 {
4226   output_constant_pool_contents (shared_constant_pool);
4227 }
4228 
4229 /* Determine what kind of relocations EXP may need.  */
4230 
4231 int
compute_reloc_for_constant(tree exp)4232 compute_reloc_for_constant (tree exp)
4233 {
4234   int reloc = 0, reloc2;
4235   tree tem;
4236 
4237   switch (TREE_CODE (exp))
4238     {
4239     case ADDR_EXPR:
4240     case FDESC_EXPR:
4241       /* Go inside any operations that get_inner_reference can handle and see
4242 	 if what's inside is a constant: no need to do anything here for
4243 	 addresses of variables or functions.  */
4244       for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4245 	   tem = TREE_OPERAND (tem, 0))
4246 	;
4247 
4248       if (TREE_CODE (tem) == MEM_REF
4249 	  && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4250 	{
4251 	  reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4252 	  break;
4253 	}
4254 
4255       if (!targetm.binds_local_p (tem))
4256 	reloc |= 2;
4257       else
4258 	reloc |= 1;
4259       break;
4260 
4261     case PLUS_EXPR:
4262     case POINTER_PLUS_EXPR:
4263       reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4264       reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4265       break;
4266 
4267     case MINUS_EXPR:
4268       reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4269       reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4270       /* The difference of two local labels is computable at link time.  */
4271       if (reloc == 1 && reloc2 == 1)
4272 	reloc = 0;
4273       else
4274 	reloc |= reloc2;
4275       break;
4276 
4277     CASE_CONVERT:
4278     case VIEW_CONVERT_EXPR:
4279       reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4280       break;
4281 
4282     case CONSTRUCTOR:
4283       {
4284 	unsigned HOST_WIDE_INT idx;
4285 	FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4286 	  if (tem != 0)
4287 	    reloc |= compute_reloc_for_constant (tem);
4288       }
4289       break;
4290 
4291     default:
4292       break;
4293     }
4294   return reloc;
4295 }
4296 
4297 /* Find all the constants whose addresses are referenced inside of EXP,
4298    and make sure assembler code with a label has been output for each one.
4299    Indicate whether an ADDR_EXPR has been encountered.  */
4300 
4301 static void
output_addressed_constants(tree exp)4302 output_addressed_constants (tree exp)
4303 {
4304   tree tem;
4305 
4306   switch (TREE_CODE (exp))
4307     {
4308     case ADDR_EXPR:
4309     case FDESC_EXPR:
4310       /* Go inside any operations that get_inner_reference can handle and see
4311 	 if what's inside is a constant: no need to do anything here for
4312 	 addresses of variables or functions.  */
4313       for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4314 	   tem = TREE_OPERAND (tem, 0))
4315 	;
4316 
4317       /* If we have an initialized CONST_DECL, retrieve the initializer.  */
4318       if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4319 	tem = DECL_INITIAL (tem);
4320 
4321       if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4322 	output_constant_def (tem, 0);
4323 
4324       if (TREE_CODE (tem) == MEM_REF)
4325 	output_addressed_constants (TREE_OPERAND (tem, 0));
4326       break;
4327 
4328     case PLUS_EXPR:
4329     case POINTER_PLUS_EXPR:
4330     case MINUS_EXPR:
4331       output_addressed_constants (TREE_OPERAND (exp, 1));
4332       gcc_fallthrough ();
4333 
4334     CASE_CONVERT:
4335     case VIEW_CONVERT_EXPR:
4336       output_addressed_constants (TREE_OPERAND (exp, 0));
4337       break;
4338 
4339     case CONSTRUCTOR:
4340       {
4341 	unsigned HOST_WIDE_INT idx;
4342 	FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4343 	  if (tem != 0)
4344 	    output_addressed_constants (tem);
4345       }
4346       break;
4347 
4348     default:
4349       break;
4350     }
4351 }
4352 
4353 /* Whether a constructor CTOR is a valid static constant initializer if all
4354    its elements are.  This used to be internal to initializer_constant_valid_p
4355    and has been exposed to let other functions like categorize_ctor_elements
4356    evaluate the property while walking a constructor for other purposes.  */
4357 
4358 bool
constructor_static_from_elts_p(const_tree ctor)4359 constructor_static_from_elts_p (const_tree ctor)
4360 {
4361   return (TREE_CONSTANT (ctor)
4362 	  && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4363 	      || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4364 	      || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4365 }
4366 
4367 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4368 					    tree *cache);
4369 
4370 /* A subroutine of initializer_constant_valid_p.  VALUE is a MINUS_EXPR,
4371    PLUS_EXPR or POINTER_PLUS_EXPR.  This looks for cases of VALUE
4372    which are valid when ENDTYPE is an integer of any size; in
4373    particular, this does not accept a pointer minus a constant.  This
4374    returns null_pointer_node if the VALUE is an absolute constant
4375    which can be used to initialize a static variable.  Otherwise it
4376    returns NULL.  */
4377 
4378 static tree
narrowing_initializer_constant_valid_p(tree value,tree endtype,tree * cache)4379 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4380 {
4381   tree op0, op1;
4382 
4383   if (!INTEGRAL_TYPE_P (endtype))
4384     return NULL_TREE;
4385 
4386   op0 = TREE_OPERAND (value, 0);
4387   op1 = TREE_OPERAND (value, 1);
4388 
4389   /* Like STRIP_NOPS except allow the operand mode to widen.  This
4390      works around a feature of fold that simplifies (int)(p1 - p2) to
4391      ((int)p1 - (int)p2) under the theory that the narrower operation
4392      is cheaper.  */
4393 
4394   while (CONVERT_EXPR_P (op0)
4395 	 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4396     {
4397       tree inner = TREE_OPERAND (op0, 0);
4398       if (inner == error_mark_node
4399 	  || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4400 	  || (GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (op0)))
4401 	      > GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (inner)))))
4402 	break;
4403       op0 = inner;
4404     }
4405 
4406   while (CONVERT_EXPR_P (op1)
4407 	 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4408     {
4409       tree inner = TREE_OPERAND (op1, 0);
4410       if (inner == error_mark_node
4411 	  || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4412 	  || (GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (op1)))
4413 	      > GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (inner)))))
4414 	break;
4415       op1 = inner;
4416     }
4417 
4418   op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4419   if (!op0)
4420     return NULL_TREE;
4421 
4422   op1 = initializer_constant_valid_p_1 (op1, endtype,
4423 					cache ? cache + 2 : NULL);
4424   /* Both initializers must be known.  */
4425   if (op1)
4426     {
4427       if (op0 == op1
4428 	  && (op0 == null_pointer_node
4429 	      || TREE_CODE (value) == MINUS_EXPR))
4430 	return null_pointer_node;
4431 
4432       /* Support differences between labels.  */
4433       if (TREE_CODE (op0) == LABEL_DECL
4434 	  && TREE_CODE (op1) == LABEL_DECL)
4435 	return null_pointer_node;
4436 
4437       if (TREE_CODE (op0) == STRING_CST
4438 	  && TREE_CODE (op1) == STRING_CST
4439 	  && operand_equal_p (op0, op1, 1))
4440 	return null_pointer_node;
4441     }
4442 
4443   return NULL_TREE;
4444 }
4445 
4446 /* Helper function of initializer_constant_valid_p.
4447    Return nonzero if VALUE is a valid constant-valued expression
4448    for use in initializing a static variable; one that can be an
4449    element of a "constant" initializer.
4450 
4451    Return null_pointer_node if the value is absolute;
4452    if it is relocatable, return the variable that determines the relocation.
4453    We assume that VALUE has been folded as much as possible;
4454    therefore, we do not need to check for such things as
4455    arithmetic-combinations of integers.
4456 
4457    Use CACHE (pointer to 2 tree values) for caching if non-NULL.  */
4458 
4459 static tree
initializer_constant_valid_p_1(tree value,tree endtype,tree * cache)4460 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4461 {
4462   tree ret;
4463 
4464   switch (TREE_CODE (value))
4465     {
4466     case CONSTRUCTOR:
4467       if (constructor_static_from_elts_p (value))
4468 	{
4469 	  unsigned HOST_WIDE_INT idx;
4470 	  tree elt;
4471 	  bool absolute = true;
4472 
4473 	  if (cache && cache[0] == value)
4474 	    return cache[1];
4475 	  FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4476 	    {
4477 	      tree reloc;
4478 	      reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4479 						      NULL);
4480 	      if (!reloc
4481 		  /* An absolute value is required with reverse SSO.  */
4482 		  || (reloc != null_pointer_node
4483 		      && TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (value))
4484 		      && !AGGREGATE_TYPE_P (TREE_TYPE (elt))))
4485 		{
4486 		  if (cache)
4487 		    {
4488 		      cache[0] = value;
4489 		      cache[1] = NULL_TREE;
4490 		    }
4491 		  return NULL_TREE;
4492 		}
4493 	      if (reloc != null_pointer_node)
4494 		absolute = false;
4495 	    }
4496 	  /* For a non-absolute relocation, there is no single
4497 	     variable that can be "the variable that determines the
4498 	     relocation."  */
4499 	  if (cache)
4500 	    {
4501 	      cache[0] = value;
4502 	      cache[1] = absolute ? null_pointer_node : error_mark_node;
4503 	    }
4504 	  return absolute ? null_pointer_node : error_mark_node;
4505 	}
4506 
4507       return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4508 
4509     case INTEGER_CST:
4510     case VECTOR_CST:
4511     case REAL_CST:
4512     case FIXED_CST:
4513     case STRING_CST:
4514     case COMPLEX_CST:
4515       return null_pointer_node;
4516 
4517     case ADDR_EXPR:
4518     case FDESC_EXPR:
4519       {
4520 	tree op0 = staticp (TREE_OPERAND (value, 0));
4521 	if (op0)
4522 	  {
4523 	    /* "&(*a).f" is like unto pointer arithmetic.  If "a" turns out
4524 	       to be a constant, this is old-skool offsetof-like nonsense.  */
4525 	    if (TREE_CODE (op0) == INDIRECT_REF
4526 		&& TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4527 	      return null_pointer_node;
4528 	    /* Taking the address of a nested function involves a trampoline,
4529 	       unless we don't need or want one.  */
4530 	    if (TREE_CODE (op0) == FUNCTION_DECL
4531 		&& DECL_STATIC_CHAIN (op0)
4532 		&& !TREE_NO_TRAMPOLINE (value))
4533 	      return NULL_TREE;
4534 	    /* "&{...}" requires a temporary to hold the constructed
4535 	       object.  */
4536 	    if (TREE_CODE (op0) == CONSTRUCTOR)
4537 	      return NULL_TREE;
4538 	  }
4539 	return op0;
4540       }
4541 
4542     case NON_LVALUE_EXPR:
4543       return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4544 					     endtype, cache);
4545 
4546     case VIEW_CONVERT_EXPR:
4547       {
4548 	tree src = TREE_OPERAND (value, 0);
4549 	tree src_type = TREE_TYPE (src);
4550 	tree dest_type = TREE_TYPE (value);
4551 
4552 	/* Allow view-conversions from aggregate to non-aggregate type only
4553 	   if the bit pattern is fully preserved afterwards; otherwise, the
4554 	   RTL expander won't be able to apply a subsequent transformation
4555 	   to the underlying constructor.  */
4556 	if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4557 	  {
4558 	    if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4559 	      return initializer_constant_valid_p_1 (src, endtype, cache);
4560 	    else
4561 	      return NULL_TREE;
4562 	  }
4563 
4564 	/* Allow all other kinds of view-conversion.  */
4565 	return initializer_constant_valid_p_1 (src, endtype, cache);
4566       }
4567 
4568     CASE_CONVERT:
4569       {
4570 	tree src = TREE_OPERAND (value, 0);
4571 	tree src_type = TREE_TYPE (src);
4572 	tree dest_type = TREE_TYPE (value);
4573 
4574 	/* Allow conversions between pointer types, floating-point
4575 	   types, and offset types.  */
4576 	if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4577 	    || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4578 	    || (TREE_CODE (dest_type) == OFFSET_TYPE
4579 		&& TREE_CODE (src_type) == OFFSET_TYPE))
4580 	  return initializer_constant_valid_p_1 (src, endtype, cache);
4581 
4582 	/* Allow length-preserving conversions between integer types.  */
4583 	if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4584 	    && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4585 	  return initializer_constant_valid_p_1 (src, endtype, cache);
4586 
4587 	/* Allow conversions between other integer types only if
4588 	   explicit value.  Don't allow sign-extension to a type larger
4589 	   than word and pointer, there aren't relocations that would
4590 	   allow to sign extend it to a wider type.  */
4591 	if (INTEGRAL_TYPE_P (dest_type)
4592 	    && INTEGRAL_TYPE_P (src_type)
4593 	    && (TYPE_UNSIGNED (src_type)
4594 		|| TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type)
4595 		|| TYPE_PRECISION (dest_type) <= BITS_PER_WORD
4596 		|| TYPE_PRECISION (dest_type) <= POINTER_SIZE))
4597 	  {
4598 	    tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4599 	    if (inner == null_pointer_node)
4600 	      return null_pointer_node;
4601 	    break;
4602 	  }
4603 
4604 	/* Allow (int) &foo provided int is as wide as a pointer.  */
4605 	if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4606 	    && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4607 	  return initializer_constant_valid_p_1 (src, endtype, cache);
4608 
4609 	/* Likewise conversions from int to pointers, but also allow
4610 	   conversions from 0.  */
4611 	if ((POINTER_TYPE_P (dest_type)
4612 	     || TREE_CODE (dest_type) == OFFSET_TYPE)
4613 	    && INTEGRAL_TYPE_P (src_type))
4614 	  {
4615 	    if (TREE_CODE (src) == INTEGER_CST
4616 		&& TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4617 	      return null_pointer_node;
4618 	    if (integer_zerop (src))
4619 	      return null_pointer_node;
4620 	    else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4621 	      return initializer_constant_valid_p_1 (src, endtype, cache);
4622 	  }
4623 
4624 	/* Allow conversions to struct or union types if the value
4625 	   inside is okay.  */
4626 	if (TREE_CODE (dest_type) == RECORD_TYPE
4627 	    || TREE_CODE (dest_type) == UNION_TYPE)
4628 	  return initializer_constant_valid_p_1 (src, endtype, cache);
4629       }
4630       break;
4631 
4632     case POINTER_PLUS_EXPR:
4633     case PLUS_EXPR:
4634       /* Any valid floating-point constants will have been folded by now;
4635 	 with -frounding-math we hit this with addition of two constants.  */
4636       if (TREE_CODE (endtype) == REAL_TYPE)
4637 	return NULL_TREE;
4638       if (cache && cache[0] == value)
4639 	return cache[1];
4640       if (! INTEGRAL_TYPE_P (endtype)
4641 	  || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4642 	{
4643 	  tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4644 	  tree valid0
4645 	    = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4646 					      endtype, ncache);
4647 	  tree valid1
4648 	    = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4649 					      endtype, ncache + 2);
4650 	  /* If either term is absolute, use the other term's relocation.  */
4651 	  if (valid0 == null_pointer_node)
4652 	    ret = valid1;
4653 	  else if (valid1 == null_pointer_node)
4654 	    ret = valid0;
4655 	  /* Support narrowing pointer differences.  */
4656 	  else
4657 	    ret = narrowing_initializer_constant_valid_p (value, endtype,
4658 							  ncache);
4659 	}
4660       else
4661       /* Support narrowing pointer differences.  */
4662 	ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4663       if (cache)
4664 	{
4665 	  cache[0] = value;
4666 	  cache[1] = ret;
4667 	}
4668       return ret;
4669 
4670     case POINTER_DIFF_EXPR:
4671     case MINUS_EXPR:
4672       if (TREE_CODE (endtype) == REAL_TYPE)
4673 	return NULL_TREE;
4674       if (cache && cache[0] == value)
4675 	return cache[1];
4676       if (! INTEGRAL_TYPE_P (endtype)
4677 	  || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4678 	{
4679 	  tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4680 	  tree valid0
4681 	    = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4682 					      endtype, ncache);
4683 	  tree valid1
4684 	    = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4685 					      endtype, ncache + 2);
4686 	  /* Win if second argument is absolute.  */
4687 	  if (valid1 == null_pointer_node)
4688 	    ret = valid0;
4689 	  /* Win if both arguments have the same relocation.
4690 	     Then the value is absolute.  */
4691 	  else if (valid0 == valid1 && valid0 != 0)
4692 	    ret = null_pointer_node;
4693 	  /* Since GCC guarantees that string constants are unique in the
4694 	     generated code, a subtraction between two copies of the same
4695 	     constant string is absolute.  */
4696 	  else if (valid0 && TREE_CODE (valid0) == STRING_CST
4697 		   && valid1 && TREE_CODE (valid1) == STRING_CST
4698 		   && operand_equal_p (valid0, valid1, 1))
4699 	    ret = null_pointer_node;
4700 	  /* Support narrowing differences.  */
4701 	  else
4702 	    ret = narrowing_initializer_constant_valid_p (value, endtype,
4703 							  ncache);
4704 	}
4705       else
4706 	/* Support narrowing differences.  */
4707 	ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4708       if (cache)
4709 	{
4710 	  cache[0] = value;
4711 	  cache[1] = ret;
4712 	}
4713       return ret;
4714 
4715     default:
4716       break;
4717     }
4718 
4719   return NULL_TREE;
4720 }
4721 
4722 /* Return nonzero if VALUE is a valid constant-valued expression
4723    for use in initializing a static variable; one that can be an
4724    element of a "constant" initializer.
4725 
4726    Return null_pointer_node if the value is absolute;
4727    if it is relocatable, return the variable that determines the relocation.
4728    We assume that VALUE has been folded as much as possible;
4729    therefore, we do not need to check for such things as
4730    arithmetic-combinations of integers.  */
4731 tree
initializer_constant_valid_p(tree value,tree endtype,bool reverse)4732 initializer_constant_valid_p (tree value, tree endtype, bool reverse)
4733 {
4734   tree reloc = initializer_constant_valid_p_1 (value, endtype, NULL);
4735 
4736   /* An absolute value is required with reverse storage order.  */
4737   if (reloc
4738       && reloc != null_pointer_node
4739       && reverse
4740       && !AGGREGATE_TYPE_P (endtype)
4741       && !VECTOR_TYPE_P (endtype))
4742     reloc = NULL_TREE;
4743 
4744   return reloc;
4745 }
4746 
4747 /* Return true if VALUE is a valid constant-valued expression
4748    for use in initializing a static bit-field; one that can be
4749    an element of a "constant" initializer.  */
4750 
4751 bool
initializer_constant_valid_for_bitfield_p(tree value)4752 initializer_constant_valid_for_bitfield_p (tree value)
4753 {
4754   /* For bitfields we support integer constants or possibly nested aggregates
4755      of such.  */
4756   switch (TREE_CODE (value))
4757     {
4758     case CONSTRUCTOR:
4759       {
4760 	unsigned HOST_WIDE_INT idx;
4761 	tree elt;
4762 
4763 	FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4764 	  if (!initializer_constant_valid_for_bitfield_p (elt))
4765 	    return false;
4766 	return true;
4767       }
4768 
4769     case INTEGER_CST:
4770     case REAL_CST:
4771       return true;
4772 
4773     case VIEW_CONVERT_EXPR:
4774     case NON_LVALUE_EXPR:
4775       return
4776 	initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4777 
4778     default:
4779       break;
4780     }
4781 
4782   return false;
4783 }
4784 
4785 /* output_constructor outer state of relevance in recursive calls, typically
4786    for nested aggregate bitfields.  */
4787 
4788 struct oc_outer_state {
4789   unsigned int bit_offset;  /* current position in ...  */
4790   int byte;                 /* ... the outer byte buffer.  */
4791 };
4792 
4793 static unsigned HOST_WIDE_INT
4794 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int, bool,
4795 		    oc_outer_state *);
4796 
4797 /* Output assembler code for constant EXP, with no label.
4798    This includes the pseudo-op such as ".int" or ".byte", and a newline.
4799    Assumes output_addressed_constants has been done on EXP already.
4800 
4801    Generate at least SIZE bytes of assembler data, padding at the end
4802    with zeros if necessary.  SIZE must always be specified.  The returned
4803    value is the actual number of bytes of assembler data generated, which
4804    may be bigger than SIZE if the object contains a variable length field.
4805 
4806    SIZE is important for structure constructors,
4807    since trailing members may have been omitted from the constructor.
4808    It is also important for initialization of arrays from string constants
4809    since the full length of the string constant might not be wanted.
4810    It is also needed for initialization of unions, where the initializer's
4811    type is just one member, and that may not be as long as the union.
4812 
4813    There a case in which we would fail to output exactly SIZE bytes:
4814    for a structure constructor that wants to produce more than SIZE bytes.
4815    But such constructors will never be generated for any possible input.
4816 
4817    ALIGN is the alignment of the data in bits.
4818 
4819    If REVERSE is true, EXP is output in reverse storage order.  */
4820 
4821 static unsigned HOST_WIDE_INT
output_constant(tree exp,unsigned HOST_WIDE_INT size,unsigned int align,bool reverse)4822 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align,
4823 		 bool reverse)
4824 {
4825   enum tree_code code;
4826   unsigned HOST_WIDE_INT thissize;
4827   rtx cst;
4828 
4829   if (size == 0 || flag_syntax_only)
4830     return size;
4831 
4832   /* See if we're trying to initialize a pointer in a non-default mode
4833      to the address of some declaration somewhere.  If the target says
4834      the mode is valid for pointers, assume the target has a way of
4835      resolving it.  */
4836   if (TREE_CODE (exp) == NOP_EXPR
4837       && POINTER_TYPE_P (TREE_TYPE (exp))
4838       && targetm.addr_space.valid_pointer_mode
4839 	   (SCALAR_INT_TYPE_MODE (TREE_TYPE (exp)),
4840 	    TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4841     {
4842       tree saved_type = TREE_TYPE (exp);
4843 
4844       /* Peel off any intermediate conversions-to-pointer for valid
4845 	 pointer modes.  */
4846       while (TREE_CODE (exp) == NOP_EXPR
4847 	     && POINTER_TYPE_P (TREE_TYPE (exp))
4848 	     && targetm.addr_space.valid_pointer_mode
4849 		  (SCALAR_INT_TYPE_MODE (TREE_TYPE (exp)),
4850 		   TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4851 	exp = TREE_OPERAND (exp, 0);
4852 
4853       /* If what we're left with is the address of something, we can
4854 	 convert the address to the final type and output it that
4855 	 way.  */
4856       if (TREE_CODE (exp) == ADDR_EXPR)
4857 	exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4858       /* Likewise for constant ints.  */
4859       else if (TREE_CODE (exp) == INTEGER_CST)
4860 	exp = fold_convert (saved_type, exp);
4861 
4862     }
4863 
4864   /* Eliminate any conversions since we'll be outputting the underlying
4865      constant.  */
4866   while (CONVERT_EXPR_P (exp)
4867 	 || TREE_CODE (exp) == NON_LVALUE_EXPR
4868 	 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4869     {
4870       HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4871       HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4872 
4873       /* Make sure eliminating the conversion is really a no-op, except with
4874 	 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4875 	 union types to allow for Ada unchecked unions.  */
4876       if (type_size > op_size
4877 	  && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4878 	  && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4879 	/* Keep the conversion. */
4880 	break;
4881       else
4882 	exp = TREE_OPERAND (exp, 0);
4883     }
4884 
4885   code = TREE_CODE (TREE_TYPE (exp));
4886   thissize = int_size_in_bytes (TREE_TYPE (exp));
4887 
4888   /* Allow a constructor with no elements for any data type.
4889      This means to fill the space with zeros.  */
4890   if (TREE_CODE (exp) == CONSTRUCTOR
4891       && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4892     {
4893       assemble_zeros (size);
4894       return size;
4895     }
4896 
4897   if (TREE_CODE (exp) == FDESC_EXPR)
4898     {
4899 #ifdef ASM_OUTPUT_FDESC
4900       HOST_WIDE_INT part = tree_to_shwi (TREE_OPERAND (exp, 1));
4901       tree decl = TREE_OPERAND (exp, 0);
4902       ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4903 #else
4904       gcc_unreachable ();
4905 #endif
4906       return size;
4907     }
4908 
4909   /* Now output the underlying data.  If we've handling the padding, return.
4910      Otherwise, break and ensure SIZE is the size written.  */
4911   switch (code)
4912     {
4913     case BOOLEAN_TYPE:
4914     case INTEGER_TYPE:
4915     case ENUMERAL_TYPE:
4916     case POINTER_TYPE:
4917     case REFERENCE_TYPE:
4918     case OFFSET_TYPE:
4919     case FIXED_POINT_TYPE:
4920     case POINTER_BOUNDS_TYPE:
4921     case NULLPTR_TYPE:
4922       cst = expand_expr (exp, NULL_RTX, VOIDmode, EXPAND_INITIALIZER);
4923       if (reverse)
4924 	cst = flip_storage_order (TYPE_MODE (TREE_TYPE (exp)), cst);
4925       if (!assemble_integer (cst, MIN (size, thissize), align, 0))
4926 	error ("initializer for integer/fixed-point value is too complicated");
4927       break;
4928 
4929     case REAL_TYPE:
4930       if (TREE_CODE (exp) != REAL_CST)
4931 	error ("initializer for floating value is not a floating constant");
4932       else
4933 	assemble_real (TREE_REAL_CST (exp),
4934 		       SCALAR_FLOAT_TYPE_MODE (TREE_TYPE (exp)),
4935 		       align, reverse);
4936       break;
4937 
4938     case COMPLEX_TYPE:
4939       output_constant (TREE_REALPART (exp), thissize / 2, align, reverse);
4940       output_constant (TREE_IMAGPART (exp), thissize / 2,
4941 		       min_align (align, BITS_PER_UNIT * (thissize / 2)),
4942 		       reverse);
4943       break;
4944 
4945     case ARRAY_TYPE:
4946     case VECTOR_TYPE:
4947       switch (TREE_CODE (exp))
4948 	{
4949 	case CONSTRUCTOR:
4950 	  return output_constructor (exp, size, align, reverse, NULL);
4951 	case STRING_CST:
4952 	  thissize
4953 	    = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4954 	  assemble_string (TREE_STRING_POINTER (exp), thissize);
4955 	  break;
4956 	case VECTOR_CST:
4957 	  {
4958 	    scalar_mode inner = SCALAR_TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4959 	    unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4960 	    int elt_size = GET_MODE_SIZE (inner);
4961 	    output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align,
4962 			     reverse);
4963 	    thissize = elt_size;
4964 	    /* Static constants must have a fixed size.  */
4965 	    unsigned int nunits = VECTOR_CST_NELTS (exp).to_constant ();
4966 	    for (unsigned int i = 1; i < nunits; i++)
4967 	      {
4968 		output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign,
4969 				 reverse);
4970 		thissize += elt_size;
4971 	      }
4972 	    break;
4973 	  }
4974 	default:
4975 	  gcc_unreachable ();
4976 	}
4977       break;
4978 
4979     case RECORD_TYPE:
4980     case UNION_TYPE:
4981       gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4982       return output_constructor (exp, size, align, reverse, NULL);
4983 
4984     case ERROR_MARK:
4985       return 0;
4986 
4987     default:
4988       gcc_unreachable ();
4989     }
4990 
4991   if (size > thissize)
4992     assemble_zeros (size - thissize);
4993 
4994   return size;
4995 }
4996 
4997 /* Subroutine of output_constructor, used for computing the size of
4998    arrays of unspecified length.  VAL must be a CONSTRUCTOR of an array
4999    type with an unspecified upper bound.  */
5000 
5001 static unsigned HOST_WIDE_INT
array_size_for_constructor(tree val)5002 array_size_for_constructor (tree val)
5003 {
5004   tree max_index;
5005   unsigned HOST_WIDE_INT cnt;
5006   tree index, value, tmp;
5007   offset_int i;
5008 
5009   /* This code used to attempt to handle string constants that are not
5010      arrays of single-bytes, but nothing else does, so there's no point in
5011      doing it here.  */
5012   if (TREE_CODE (val) == STRING_CST)
5013     return TREE_STRING_LENGTH (val);
5014 
5015   max_index = NULL_TREE;
5016   FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
5017     {
5018       if (TREE_CODE (index) == RANGE_EXPR)
5019 	index = TREE_OPERAND (index, 1);
5020       if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
5021 	max_index = index;
5022     }
5023 
5024   if (max_index == NULL_TREE)
5025     return 0;
5026 
5027   /* Compute the total number of array elements.  */
5028   tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
5029   i = wi::to_offset (max_index) - wi::to_offset (tmp) + 1;
5030 
5031   /* Multiply by the array element unit size to find number of bytes.  */
5032   i *= wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
5033 
5034   gcc_assert (wi::fits_uhwi_p (i));
5035   return i.to_uhwi ();
5036 }
5037 
5038 /* Other datastructures + helpers for output_constructor.  */
5039 
5040 /* output_constructor local state to support interaction with helpers.  */
5041 
5042 struct oc_local_state {
5043 
5044   /* Received arguments.  */
5045   tree exp;                     /* Constructor expression.  */
5046   tree type;                    /* Type of constructor expression.  */
5047   unsigned HOST_WIDE_INT size;  /* # bytes to output - pad if necessary.  */
5048   unsigned int align;           /* Known initial alignment.  */
5049   tree min_index;               /* Lower bound if specified for an array.  */
5050 
5051   /* Output processing state.  */
5052   HOST_WIDE_INT total_bytes;  /* # bytes output so far / current position.  */
5053   int byte;                   /* Part of a bitfield byte yet to be output.  */
5054   int last_relative_index;    /* Implicit or explicit index of the last
5055 				 array element output within a bitfield.  */
5056   bool byte_buffer_in_use;    /* Whether BYTE is in use.  */
5057   bool reverse;               /* Whether reverse storage order is in use.  */
5058 
5059   /* Current element.  */
5060   tree field;      /* Current field decl in a record.  */
5061   tree val;        /* Current element value.  */
5062   tree index;      /* Current element index.  */
5063 
5064 };
5065 
5066 /* Helper for output_constructor.  From the current LOCAL state, output a
5067    RANGE_EXPR element.  */
5068 
5069 static void
output_constructor_array_range(oc_local_state * local)5070 output_constructor_array_range (oc_local_state *local)
5071 {
5072   unsigned HOST_WIDE_INT fieldsize
5073     = int_size_in_bytes (TREE_TYPE (local->type));
5074 
5075   HOST_WIDE_INT lo_index
5076     = tree_to_shwi (TREE_OPERAND (local->index, 0));
5077   HOST_WIDE_INT hi_index
5078     = tree_to_shwi (TREE_OPERAND (local->index, 1));
5079   HOST_WIDE_INT index;
5080 
5081   unsigned int align2
5082     = min_align (local->align, fieldsize * BITS_PER_UNIT);
5083 
5084   for (index = lo_index; index <= hi_index; index++)
5085     {
5086       /* Output the element's initial value.  */
5087       if (local->val == NULL_TREE)
5088 	assemble_zeros (fieldsize);
5089       else
5090 	fieldsize
5091 	  = output_constant (local->val, fieldsize, align2, local->reverse);
5092 
5093       /* Count its size.  */
5094       local->total_bytes += fieldsize;
5095     }
5096 }
5097 
5098 /* Helper for output_constructor.  From the current LOCAL state, output a
5099    field element that is not true bitfield or part of an outer one.  */
5100 
5101 static void
output_constructor_regular_field(oc_local_state * local)5102 output_constructor_regular_field (oc_local_state *local)
5103 {
5104   /* Field size and position.  Since this structure is static, we know the
5105      positions are constant.  */
5106   unsigned HOST_WIDE_INT fieldsize;
5107   HOST_WIDE_INT fieldpos;
5108 
5109   unsigned int align2;
5110 
5111   /* Output any buffered-up bit-fields preceding this element.  */
5112   if (local->byte_buffer_in_use)
5113     {
5114       assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5115       local->total_bytes++;
5116       local->byte_buffer_in_use = false;
5117     }
5118 
5119   if (local->index != NULL_TREE)
5120     {
5121       /* Perform the index calculation in modulo arithmetic but
5122 	 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
5123 	 but we are using an unsigned sizetype.  */
5124       unsigned prec = TYPE_PRECISION (sizetype);
5125       offset_int idx = wi::sext (wi::to_offset (local->index)
5126 				 - wi::to_offset (local->min_index), prec);
5127       fieldpos = (idx * wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (local->val))))
5128 	.to_short_addr ();
5129     }
5130   else if (local->field != NULL_TREE)
5131     fieldpos = int_byte_position (local->field);
5132   else
5133     fieldpos = 0;
5134 
5135   /* Advance to offset of this element.
5136      Note no alignment needed in an array, since that is guaranteed
5137      if each element has the proper size.  */
5138   if (local->field != NULL_TREE || local->index != NULL_TREE)
5139     {
5140       if (fieldpos > local->total_bytes)
5141 	{
5142 	  assemble_zeros (fieldpos - local->total_bytes);
5143 	  local->total_bytes = fieldpos;
5144 	}
5145       else
5146 	/* Must not go backwards.  */
5147 	gcc_assert (fieldpos == local->total_bytes);
5148     }
5149 
5150   /* Find the alignment of this element.  */
5151   align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
5152 
5153   /* Determine size this element should occupy.  */
5154   if (local->field)
5155     {
5156       fieldsize = 0;
5157 
5158       /* If this is an array with an unspecified upper bound,
5159 	 the initializer determines the size.  */
5160       /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
5161 	 but we cannot do this until the deprecated support for
5162 	 initializing zero-length array members is removed.  */
5163       if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
5164 	  && (!TYPE_DOMAIN (TREE_TYPE (local->field))
5165 	      || !TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field)))))
5166 	{
5167 	  fieldsize = array_size_for_constructor (local->val);
5168 	  /* Given a non-empty initialization, this field had better
5169 	     be last.  Given a flexible array member, the next field
5170 	     on the chain is a TYPE_DECL of the enclosing struct.  */
5171 	  const_tree next = DECL_CHAIN (local->field);
5172 	  gcc_assert (!fieldsize || !next || TREE_CODE (next) != FIELD_DECL);
5173 	}
5174       else
5175 	fieldsize = tree_to_uhwi (DECL_SIZE_UNIT (local->field));
5176     }
5177   else
5178     fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
5179 
5180   /* Output the element's initial value.  */
5181   if (local->val == NULL_TREE)
5182     assemble_zeros (fieldsize);
5183   else
5184     fieldsize
5185       = output_constant (local->val, fieldsize, align2, local->reverse);
5186 
5187   /* Count its size.  */
5188   local->total_bytes += fieldsize;
5189 }
5190 
5191 /* Helper for output_constructor.  From the LOCAL state, output an element
5192    that is a true bitfield or part of an outer one.  BIT_OFFSET is the offset
5193    from the start of a possibly ongoing outer byte buffer.  */
5194 
5195 static void
output_constructor_bitfield(oc_local_state * local,unsigned int bit_offset)5196 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
5197 {
5198   /* Bit size of this element.  */
5199   HOST_WIDE_INT ebitsize
5200     = (local->field
5201        ? tree_to_uhwi (DECL_SIZE (local->field))
5202        : tree_to_uhwi (TYPE_SIZE (TREE_TYPE (local->type))));
5203 
5204   /* Relative index of this element if this is an array component.  */
5205   HOST_WIDE_INT relative_index
5206     = (!local->field
5207        ? (local->index
5208 	  ? (tree_to_shwi (local->index)
5209 	     - tree_to_shwi (local->min_index))
5210 	  : local->last_relative_index + 1)
5211        : 0);
5212 
5213   /* Bit position of this element from the start of the containing
5214      constructor.  */
5215   HOST_WIDE_INT constructor_relative_ebitpos
5216       = (local->field
5217 	 ? int_bit_position (local->field)
5218 	 : ebitsize * relative_index);
5219 
5220   /* Bit position of this element from the start of a possibly ongoing
5221      outer byte buffer.  */
5222   HOST_WIDE_INT byte_relative_ebitpos
5223     = bit_offset + constructor_relative_ebitpos;
5224 
5225   /* From the start of a possibly ongoing outer byte buffer, offsets to
5226      the first bit of this element and to the first bit past the end of
5227      this element.  */
5228   HOST_WIDE_INT next_offset = byte_relative_ebitpos;
5229   HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
5230 
5231   local->last_relative_index = relative_index;
5232 
5233   if (local->val == NULL_TREE)
5234     local->val = integer_zero_node;
5235 
5236   while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
5237 	 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
5238     local->val = TREE_OPERAND (local->val, 0);
5239 
5240   if (TREE_CODE (local->val) != INTEGER_CST
5241       && TREE_CODE (local->val) != CONSTRUCTOR)
5242     {
5243       error ("invalid initial value for member %qE", DECL_NAME (local->field));
5244       return;
5245     }
5246 
5247   /* If this field does not start in this (or next) byte, skip some bytes.  */
5248   if (next_offset / BITS_PER_UNIT != local->total_bytes)
5249     {
5250       /* Output remnant of any bit field in previous bytes.  */
5251       if (local->byte_buffer_in_use)
5252 	{
5253 	  assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5254 	  local->total_bytes++;
5255 	  local->byte_buffer_in_use = false;
5256 	}
5257 
5258       /* If still not at proper byte, advance to there.  */
5259       if (next_offset / BITS_PER_UNIT != local->total_bytes)
5260 	{
5261 	  gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
5262 	  assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
5263 	  local->total_bytes = next_offset / BITS_PER_UNIT;
5264 	}
5265     }
5266 
5267   /* Set up the buffer if necessary.  */
5268   if (!local->byte_buffer_in_use)
5269     {
5270       local->byte = 0;
5271       if (ebitsize > 0)
5272 	local->byte_buffer_in_use = true;
5273     }
5274 
5275   /* If this is nested constructor, recurse passing the bit offset and the
5276      pending data, then retrieve the new pending data afterwards.  */
5277   if (TREE_CODE (local->val) == CONSTRUCTOR)
5278     {
5279       oc_outer_state temp_state;
5280       temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5281       temp_state.byte = local->byte;
5282       local->total_bytes
5283 	+= output_constructor (local->val, 0, 0, local->reverse, &temp_state);
5284       local->byte = temp_state.byte;
5285       return;
5286     }
5287 
5288   /* Otherwise, we must split the element into pieces that fall within
5289      separate bytes, and combine each byte with previous or following
5290      bit-fields.  */
5291   while (next_offset < end_offset)
5292     {
5293       int this_time;
5294       int shift;
5295       unsigned HOST_WIDE_INT value;
5296       HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5297       HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5298 
5299       /* Advance from byte to byte within this element when necessary.  */
5300       while (next_byte != local->total_bytes)
5301 	{
5302 	  assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5303 	  local->total_bytes++;
5304 	  local->byte = 0;
5305 	}
5306 
5307       /* Number of bits we can process at once (all part of the same byte).  */
5308       this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5309       if (local->reverse ? !BYTES_BIG_ENDIAN : BYTES_BIG_ENDIAN)
5310 	{
5311 	  /* For big-endian data, take the most significant bits (of the
5312 	     bits that are significant) first and put them into bytes from
5313 	     the most significant end.  */
5314 	  shift = end_offset - next_offset - this_time;
5315 
5316 	  /* Don't try to take a bunch of bits that cross
5317 	     the word boundary in the INTEGER_CST.  We can
5318 	     only select bits from one element.  */
5319 	  if ((shift / HOST_BITS_PER_WIDE_INT)
5320 	      != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5321 	    {
5322 	      const int end = shift + this_time - 1;
5323 	      shift = end & -HOST_BITS_PER_WIDE_INT;
5324 	      this_time = end - shift + 1;
5325 	    }
5326 
5327 	  /* Now get the bits we want to insert.  */
5328 	  value = wi::extract_uhwi (wi::to_widest (local->val),
5329 				    shift, this_time);
5330 
5331 	  /* Get the result.  This works only when:
5332 	     1 <= this_time <= HOST_BITS_PER_WIDE_INT.  */
5333 	  local->byte |= value << (BITS_PER_UNIT - this_time - next_bit);
5334 	}
5335       else
5336 	{
5337 	  /* On little-endian machines, take the least significant bits of
5338 	     the value first and pack them starting at the least significant
5339 	     bits of the bytes.  */
5340 	  shift = next_offset - byte_relative_ebitpos;
5341 
5342 	  /* Don't try to take a bunch of bits that cross
5343 	     the word boundary in the INTEGER_CST.  We can
5344 	     only select bits from one element.  */
5345 	  if ((shift / HOST_BITS_PER_WIDE_INT)
5346 	      != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5347 	    this_time
5348 	      = HOST_BITS_PER_WIDE_INT - (shift & (HOST_BITS_PER_WIDE_INT - 1));
5349 
5350 	  /* Now get the bits we want to insert.  */
5351 	  value = wi::extract_uhwi (wi::to_widest (local->val),
5352 				    shift, this_time);
5353 
5354 	  /* Get the result.  This works only when:
5355 	     1 <= this_time <= HOST_BITS_PER_WIDE_INT.  */
5356 	  local->byte |= value << next_bit;
5357 	}
5358 
5359       next_offset += this_time;
5360       local->byte_buffer_in_use = true;
5361     }
5362 }
5363 
5364 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5365    Generate at least SIZE bytes, padding if necessary.  OUTER designates the
5366    caller output state of relevance in recursive invocations.  */
5367 
5368 static unsigned HOST_WIDE_INT
output_constructor(tree exp,unsigned HOST_WIDE_INT size,unsigned int align,bool reverse,oc_outer_state * outer)5369 output_constructor (tree exp, unsigned HOST_WIDE_INT size, unsigned int align,
5370 		    bool reverse, oc_outer_state *outer)
5371 {
5372   unsigned HOST_WIDE_INT cnt;
5373   constructor_elt *ce;
5374   oc_local_state local;
5375 
5376   /* Setup our local state to communicate with helpers.  */
5377   local.exp = exp;
5378   local.type = TREE_TYPE (exp);
5379   local.size = size;
5380   local.align = align;
5381   if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5382     local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5383   else
5384     local.min_index = integer_zero_node;
5385 
5386   local.total_bytes = 0;
5387   local.byte_buffer_in_use = outer != NULL;
5388   local.byte = outer ? outer->byte : 0;
5389   local.last_relative_index = -1;
5390   /* The storage order is specified for every aggregate type.  */
5391   if (AGGREGATE_TYPE_P (local.type))
5392     local.reverse = TYPE_REVERSE_STORAGE_ORDER (local.type);
5393   else
5394     local.reverse = reverse;
5395 
5396   gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5397 
5398   /* As CE goes through the elements of the constant, FIELD goes through the
5399      structure fields if the constant is a structure.  If the constant is a
5400      union, we override this by getting the field from the TREE_LIST element.
5401      But the constant could also be an array.  Then FIELD is zero.
5402 
5403      There is always a maximum of one element in the chain LINK for unions
5404      (even if the initializer in a source program incorrectly contains
5405      more one).  */
5406 
5407   if (TREE_CODE (local.type) == RECORD_TYPE)
5408     local.field = TYPE_FIELDS (local.type);
5409   else
5410     local.field = NULL_TREE;
5411 
5412   for (cnt = 0;
5413        vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5414        cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5415     {
5416       local.val = ce->value;
5417       local.index = NULL_TREE;
5418 
5419       /* The element in a union constructor specifies the proper field
5420 	 or index.  */
5421       if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5422 	local.field = ce->index;
5423 
5424       else if (TREE_CODE (local.type) == ARRAY_TYPE)
5425 	local.index = ce->index;
5426 
5427       if (local.field && flag_verbose_asm)
5428 	fprintf (asm_out_file, "%s %s:\n",
5429 		 ASM_COMMENT_START,
5430 		 DECL_NAME (local.field)
5431 		 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5432 		 : "<anonymous>");
5433 
5434       /* Eliminate the marker that makes a cast not be an lvalue.  */
5435       if (local.val != NULL_TREE)
5436 	STRIP_NOPS (local.val);
5437 
5438       /* Output the current element, using the appropriate helper ...  */
5439 
5440       /* For an array slice not part of an outer bitfield.  */
5441       if (!outer
5442 	  && local.index != NULL_TREE
5443 	  && TREE_CODE (local.index) == RANGE_EXPR)
5444 	output_constructor_array_range (&local);
5445 
5446       /* For a field that is neither a true bitfield nor part of an outer one,
5447 	 known to be at least byte aligned and multiple-of-bytes long.  */
5448       else if (!outer
5449 	       && (local.field == NULL_TREE
5450 		   || !CONSTRUCTOR_BITFIELD_P (local.field)))
5451 	output_constructor_regular_field (&local);
5452 
5453       /* For a true bitfield or part of an outer one.  Only INTEGER_CSTs are
5454 	 supported for scalar fields, so we may need to convert first.  */
5455       else
5456         {
5457 	  if (TREE_CODE (local.val) == REAL_CST)
5458 	    local.val
5459 	      = fold_unary (VIEW_CONVERT_EXPR,
5460 			    build_nonstandard_integer_type
5461 			    (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5462 			    local.val);
5463 	  output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5464 	}
5465     }
5466 
5467   /* If we are not at toplevel, save the pending data for our caller.
5468      Otherwise output the pending data and padding zeros as needed. */
5469   if (outer)
5470     outer->byte = local.byte;
5471   else
5472     {
5473       if (local.byte_buffer_in_use)
5474 	{
5475 	  assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5476 	  local.total_bytes++;
5477 	}
5478 
5479       if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5480 	{
5481 	  assemble_zeros (local.size - local.total_bytes);
5482 	  local.total_bytes = local.size;
5483 	}
5484     }
5485 
5486   return local.total_bytes;
5487 }
5488 
5489 /* Mark DECL as weak.  */
5490 
5491 static void
mark_weak(tree decl)5492 mark_weak (tree decl)
5493 {
5494   if (DECL_WEAK (decl))
5495     return;
5496 
5497   struct symtab_node *n = symtab_node::get (decl);
5498   if (n && n->refuse_visibility_changes)
5499     error ("%+qD declared weak after being used", decl);
5500   DECL_WEAK (decl) = 1;
5501 
5502   if (DECL_RTL_SET_P (decl)
5503       && MEM_P (DECL_RTL (decl))
5504       && XEXP (DECL_RTL (decl), 0)
5505       && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5506     SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5507 }
5508 
5509 /* Merge weak status between NEWDECL and OLDDECL.  */
5510 
5511 void
merge_weak(tree newdecl,tree olddecl)5512 merge_weak (tree newdecl, tree olddecl)
5513 {
5514   if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5515     {
5516       if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5517         {
5518           tree *pwd;
5519           /* We put the NEWDECL on the weak_decls list at some point
5520              and OLDDECL as well.  Keep just OLDDECL on the list.  */
5521 	  for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5522 	    if (TREE_VALUE (*pwd) == newdecl)
5523 	      {
5524 	        *pwd = TREE_CHAIN (*pwd);
5525 		break;
5526 	      }
5527         }
5528       return;
5529     }
5530 
5531   if (DECL_WEAK (newdecl))
5532     {
5533       tree wd;
5534 
5535       /* NEWDECL is weak, but OLDDECL is not.  */
5536 
5537       /* If we already output the OLDDECL, we're in trouble; we can't
5538 	 go back and make it weak.  This should never happen in
5539 	 unit-at-a-time compilation.  */
5540       gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5541 
5542       /* If we've already generated rtl referencing OLDDECL, we may
5543 	 have done so in a way that will not function properly with
5544 	 a weak symbol.  Again in unit-at-a-time this should be
5545 	 impossible.  */
5546       gcc_assert (!TREE_USED (olddecl)
5547 	          || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5548 
5549       /* PR 49899: You cannot convert a static function into a weak, public function.  */
5550       if (! TREE_PUBLIC (olddecl) && TREE_PUBLIC (newdecl))
5551 	error ("weak declaration of %q+D being applied to a already "
5552 	       "existing, static definition", newdecl);
5553 
5554       if (TARGET_SUPPORTS_WEAK)
5555 	{
5556 	  /* We put the NEWDECL on the weak_decls list at some point.
5557 	     Replace it with the OLDDECL.  */
5558 	  for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5559 	    if (TREE_VALUE (wd) == newdecl)
5560 	      {
5561 		TREE_VALUE (wd) = olddecl;
5562 		break;
5563 	      }
5564 	  /* We may not find the entry on the list.  If NEWDECL is a
5565 	     weak alias, then we will have already called
5566 	     globalize_decl to remove the entry; in that case, we do
5567 	     not need to do anything.  */
5568 	}
5569 
5570       /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping.  */
5571       mark_weak (olddecl);
5572     }
5573   else
5574     /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5575        weak.  Just update NEWDECL to indicate that it's weak too.  */
5576     mark_weak (newdecl);
5577 }
5578 
5579 /* Declare DECL to be a weak symbol.  */
5580 
5581 void
declare_weak(tree decl)5582 declare_weak (tree decl)
5583 {
5584   gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5585   if (! TREE_PUBLIC (decl))
5586     {
5587       error ("weak declaration of %q+D must be public", decl);
5588       return;
5589     }
5590   else if (!TARGET_SUPPORTS_WEAK)
5591     warning (0, "weak declaration of %q+D not supported", decl);
5592 
5593   mark_weak (decl);
5594   if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5595     DECL_ATTRIBUTES (decl)
5596       = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5597 }
5598 
5599 static void
weak_finish_1(tree decl)5600 weak_finish_1 (tree decl)
5601 {
5602 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5603   const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5604 #endif
5605 
5606   if (! TREE_USED (decl))
5607     return;
5608 
5609 #ifdef ASM_WEAKEN_DECL
5610   ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5611 #else
5612 #ifdef ASM_WEAKEN_LABEL
5613   ASM_WEAKEN_LABEL (asm_out_file, name);
5614 #else
5615 #ifdef ASM_OUTPUT_WEAK_ALIAS
5616   {
5617     static bool warn_once = 0;
5618     if (! warn_once)
5619       {
5620 	warning (0, "only weak aliases are supported in this configuration");
5621 	warn_once = 1;
5622       }
5623     return;
5624   }
5625 #endif
5626 #endif
5627 #endif
5628 }
5629 
5630 /* Fiven an assembly name, find the decl it is associated with.  */
5631 static tree
find_decl(tree target)5632 find_decl (tree target)
5633 {
5634   symtab_node *node = symtab_node::get_for_asmname (target);
5635   if (node)
5636     return node->decl;
5637   return NULL_TREE;
5638 }
5639 
5640 /* This TREE_LIST contains weakref targets.  */
5641 
5642 static GTY(()) tree weakref_targets;
5643 
5644 /* Emit any pending weak declarations.  */
5645 
5646 void
weak_finish(void)5647 weak_finish (void)
5648 {
5649   tree t;
5650 
5651   for (t = weakref_targets; t; t = TREE_CHAIN (t))
5652     {
5653       tree alias_decl = TREE_PURPOSE (t);
5654       tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5655 
5656       if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5657 	/* Remove alias_decl from the weak list, but leave entries for
5658 	   the target alone.  */
5659 	target = NULL_TREE;
5660 #ifndef ASM_OUTPUT_WEAKREF
5661       else if (! TREE_SYMBOL_REFERENCED (target))
5662 	{
5663 	  /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5664 	     defined, otherwise we and weak_finish_1 would use
5665 	     different macros.  */
5666 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5667 	  ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5668 # else
5669 	  tree decl = find_decl (target);
5670 
5671 	  if (! decl)
5672 	    {
5673 	      decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5674 				 TREE_CODE (alias_decl), target,
5675 				 TREE_TYPE (alias_decl));
5676 
5677 	      DECL_EXTERNAL (decl) = 1;
5678 	      TREE_PUBLIC (decl) = 1;
5679 	      DECL_ARTIFICIAL (decl) = 1;
5680 	      TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5681 	      TREE_USED (decl) = 1;
5682 	    }
5683 
5684 	  weak_finish_1 (decl);
5685 # endif
5686 	}
5687 #endif
5688 
5689       {
5690 	tree *p;
5691 	tree t2;
5692 
5693 	/* Remove the alias and the target from the pending weak list
5694 	   so that we do not emit any .weak directives for the former,
5695 	   nor multiple .weak directives for the latter.  */
5696 	for (p = &weak_decls; (t2 = *p) ; )
5697 	  {
5698 	    if (TREE_VALUE (t2) == alias_decl
5699 		|| target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5700 	      *p = TREE_CHAIN (t2);
5701 	    else
5702 	      p = &TREE_CHAIN (t2);
5703 	  }
5704 
5705 	/* Remove other weakrefs to the same target, to speed things up.  */
5706 	for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5707 	  {
5708 	    if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5709 	      *p = TREE_CHAIN (t2);
5710 	    else
5711 	      p = &TREE_CHAIN (t2);
5712 	  }
5713       }
5714     }
5715 
5716   for (t = weak_decls; t; t = TREE_CHAIN (t))
5717     {
5718       tree decl = TREE_VALUE (t);
5719 
5720       weak_finish_1 (decl);
5721     }
5722 }
5723 
5724 /* Emit the assembly bits to indicate that DECL is globally visible.  */
5725 
5726 static void
globalize_decl(tree decl)5727 globalize_decl (tree decl)
5728 {
5729 
5730 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5731   if (DECL_WEAK (decl))
5732     {
5733       const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5734       tree *p, t;
5735 
5736 #ifdef ASM_WEAKEN_DECL
5737       ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5738 #else
5739       ASM_WEAKEN_LABEL (asm_out_file, name);
5740 #endif
5741 
5742       /* Remove this function from the pending weak list so that
5743 	 we do not emit multiple .weak directives for it.  */
5744       for (p = &weak_decls; (t = *p) ; )
5745 	{
5746 	  if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5747 	    *p = TREE_CHAIN (t);
5748 	  else
5749 	    p = &TREE_CHAIN (t);
5750 	}
5751 
5752       /* Remove weakrefs to the same target from the pending weakref
5753 	 list, for the same reason.  */
5754       for (p = &weakref_targets; (t = *p) ; )
5755 	{
5756 	  if (DECL_ASSEMBLER_NAME (decl)
5757 	      == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5758 	    *p = TREE_CHAIN (t);
5759 	  else
5760 	    p = &TREE_CHAIN (t);
5761 	}
5762 
5763       return;
5764     }
5765 #endif
5766 
5767   targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5768 }
5769 
5770 vec<alias_pair, va_gc> *alias_pairs;
5771 
5772 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5773    or ASM_OUTPUT_DEF_FROM_DECLS.  The function defines the symbol whose
5774    tree node is DECL to have the value of the tree node TARGET.  */
5775 
5776 void
do_assemble_alias(tree decl,tree target)5777 do_assemble_alias (tree decl, tree target)
5778 {
5779   tree id;
5780 
5781   /* Emulated TLS had better not get this var.  */
5782   gcc_assert (!(!targetm.have_tls
5783 		&& VAR_P (decl)
5784 		&& DECL_THREAD_LOCAL_P (decl)));
5785 
5786   if (TREE_ASM_WRITTEN (decl))
5787     return;
5788 
5789   id = DECL_ASSEMBLER_NAME (decl);
5790   ultimate_transparent_alias_target (&id);
5791   ultimate_transparent_alias_target (&target);
5792 
5793   /* We must force creation of DECL_RTL for debug info generation, even though
5794      we don't use it here.  */
5795   make_decl_rtl (decl);
5796 
5797   TREE_ASM_WRITTEN (decl) = 1;
5798   TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5799   TREE_ASM_WRITTEN (id) = 1;
5800 
5801   if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5802     {
5803       if (!TREE_SYMBOL_REFERENCED (target))
5804 	weakref_targets = tree_cons (decl, target, weakref_targets);
5805 
5806 #ifdef ASM_OUTPUT_WEAKREF
5807       ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5808 			  IDENTIFIER_POINTER (id),
5809 			  IDENTIFIER_POINTER (target));
5810 #else
5811       if (!TARGET_SUPPORTS_WEAK)
5812 	{
5813 	  error_at (DECL_SOURCE_LOCATION (decl),
5814 		    "weakref is not supported in this configuration");
5815 	  return;
5816 	}
5817 #endif
5818       return;
5819     }
5820 
5821 #ifdef ASM_OUTPUT_DEF
5822   tree orig_decl = decl;
5823 
5824   if (TREE_CODE (decl) == FUNCTION_DECL
5825       && cgraph_node::get (decl)->instrumentation_clone
5826       && cgraph_node::get (decl)->instrumented_version)
5827     orig_decl = cgraph_node::get (decl)->instrumented_version->decl;
5828 
5829   /* Make name accessible from other files, if appropriate.  */
5830 
5831   if (TREE_PUBLIC (decl) || TREE_PUBLIC (orig_decl))
5832     {
5833       globalize_decl (decl);
5834       maybe_assemble_visibility (decl);
5835     }
5836   if (TREE_CODE (decl) == FUNCTION_DECL
5837       && cgraph_node::get (decl)->ifunc_resolver)
5838     {
5839 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5840       if (targetm.has_ifunc_p ())
5841 	ASM_OUTPUT_TYPE_DIRECTIVE
5842 	  (asm_out_file, IDENTIFIER_POINTER (id),
5843 	   IFUNC_ASM_TYPE);
5844       else
5845 #endif
5846 	error_at (DECL_SOURCE_LOCATION (decl),
5847 		  "ifunc is not supported on this target");
5848     }
5849 
5850 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5851   ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5852 # else
5853   ASM_OUTPUT_DEF (asm_out_file,
5854 		  IDENTIFIER_POINTER (id),
5855 		  IDENTIFIER_POINTER (target));
5856 # endif
5857 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5858   {
5859     const char *name;
5860     tree *p, t;
5861 
5862     name = IDENTIFIER_POINTER (id);
5863 # ifdef ASM_WEAKEN_DECL
5864     ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5865 # else
5866     ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5867 # endif
5868     /* Remove this function from the pending weak list so that
5869        we do not emit multiple .weak directives for it.  */
5870     for (p = &weak_decls; (t = *p) ; )
5871       if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t))
5872 	  || id == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5873 	*p = TREE_CHAIN (t);
5874       else
5875 	p = &TREE_CHAIN (t);
5876 
5877     /* Remove weakrefs to the same target from the pending weakref
5878        list, for the same reason.  */
5879     for (p = &weakref_targets; (t = *p) ; )
5880       {
5881 	if (id == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5882 	  *p = TREE_CHAIN (t);
5883 	else
5884 	  p = &TREE_CHAIN (t);
5885       }
5886   }
5887 #endif
5888 }
5889 
5890 /* Emit an assembler directive to make the symbol for DECL an alias to
5891    the symbol for TARGET.  */
5892 
5893 void
assemble_alias(tree decl,tree target)5894 assemble_alias (tree decl, tree target)
5895 {
5896   tree target_decl;
5897 
5898   if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5899     {
5900       tree alias = DECL_ASSEMBLER_NAME (decl);
5901 
5902       ultimate_transparent_alias_target (&target);
5903 
5904       if (alias == target)
5905 	error ("weakref %q+D ultimately targets itself", decl);
5906       if (TREE_PUBLIC (decl))
5907 	error ("weakref %q+D must have static linkage", decl);
5908     }
5909   else
5910     {
5911 #if !defined (ASM_OUTPUT_DEF)
5912 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5913       error_at (DECL_SOURCE_LOCATION (decl),
5914 		"alias definitions not supported in this configuration");
5915       TREE_ASM_WRITTEN (decl) = 1;
5916       return;
5917 # else
5918       if (!DECL_WEAK (decl))
5919 	{
5920 	  /* NB: ifunc_resolver isn't set when an error is detected.  */
5921 	  if (TREE_CODE (decl) == FUNCTION_DECL
5922 	      && lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5923 	    error_at (DECL_SOURCE_LOCATION (decl),
5924 		      "ifunc is not supported in this configuration");
5925 	  else
5926 	    error_at (DECL_SOURCE_LOCATION (decl),
5927 		      "only weak aliases are supported in this configuration");
5928 	  TREE_ASM_WRITTEN (decl) = 1;
5929 	  return;
5930 	}
5931 # endif
5932 #endif
5933     }
5934   TREE_USED (decl) = 1;
5935 
5936   /* Allow aliases to aliases.  */
5937   if (TREE_CODE (decl) == FUNCTION_DECL)
5938     cgraph_node::get_create (decl)->alias = true;
5939   else
5940     varpool_node::get_create (decl)->alias = true;
5941 
5942   /* If the target has already been emitted, we don't have to queue the
5943      alias.  This saves a tad of memory.  */
5944   if (symtab->global_info_ready)
5945     target_decl = find_decl (target);
5946   else
5947     target_decl= NULL;
5948   if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5949       || symtab->state >= EXPANSION)
5950     do_assemble_alias (decl, target);
5951   else
5952     {
5953       alias_pair p = {decl, target};
5954       vec_safe_push (alias_pairs, p);
5955     }
5956 }
5957 
5958 /* Record and output a table of translations from original function
5959    to its transaction aware clone.  Note that tm_pure functions are
5960    considered to be their own clone.  */
5961 
5962 struct tm_clone_hasher : ggc_cache_ptr_hash<tree_map>
5963 {
hashtm_clone_hasher5964   static hashval_t hash (tree_map *m) { return tree_map_hash (m); }
equaltm_clone_hasher5965   static bool equal (tree_map *a, tree_map *b) { return tree_map_eq (a, b); }
5966 
5967   static int
keep_cache_entrytm_clone_hasher5968   keep_cache_entry (tree_map *&e)
5969   {
5970     return ggc_marked_p (e->base.from);
5971   }
5972 };
5973 
5974 static GTY((cache)) hash_table<tm_clone_hasher> *tm_clone_hash;
5975 
5976 void
record_tm_clone_pair(tree o,tree n)5977 record_tm_clone_pair (tree o, tree n)
5978 {
5979   struct tree_map **slot, *h;
5980 
5981   if (tm_clone_hash == NULL)
5982     tm_clone_hash = hash_table<tm_clone_hasher>::create_ggc (32);
5983 
5984   h = ggc_alloc<tree_map> ();
5985   h->hash = htab_hash_pointer (o);
5986   h->base.from = o;
5987   h->to = n;
5988 
5989   slot = tm_clone_hash->find_slot_with_hash (h, h->hash, INSERT);
5990   *slot = h;
5991 }
5992 
5993 tree
get_tm_clone_pair(tree o)5994 get_tm_clone_pair (tree o)
5995 {
5996   if (tm_clone_hash)
5997     {
5998       struct tree_map *h, in;
5999 
6000       in.base.from = o;
6001       in.hash = htab_hash_pointer (o);
6002       h = tm_clone_hash->find_with_hash (&in, in.hash);
6003       if (h)
6004 	return h->to;
6005     }
6006   return NULL_TREE;
6007 }
6008 
6009 struct tm_alias_pair
6010 {
6011   unsigned int uid;
6012   tree from;
6013   tree to;
6014 };
6015 
6016 
6017 /* Dump the actual pairs to the .tm_clone_table section.  */
6018 
6019 static void
dump_tm_clone_pairs(vec<tm_alias_pair> tm_alias_pairs)6020 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
6021 {
6022   unsigned i;
6023   tm_alias_pair *p;
6024   bool switched = false;
6025 
6026   FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
6027     {
6028       tree src = p->from;
6029       tree dst = p->to;
6030       struct cgraph_node *src_n = cgraph_node::get (src);
6031       struct cgraph_node *dst_n = cgraph_node::get (dst);
6032 
6033       /* The function ipa_tm_create_version() marks the clone as needed if
6034 	 the original function was needed.  But we also mark the clone as
6035 	 needed if we ever called the clone indirectly through
6036 	 TM_GETTMCLONE.  If neither of these are true, we didn't generate
6037 	 a clone, and we didn't call it indirectly... no sense keeping it
6038 	 in the clone table.  */
6039       if (!dst_n || !dst_n->definition)
6040 	continue;
6041 
6042       /* This covers the case where we have optimized the original
6043 	 function away, and only access the transactional clone.  */
6044       if (!src_n || !src_n->definition)
6045 	continue;
6046 
6047       if (!switched)
6048 	{
6049 	  switch_to_section (targetm.asm_out.tm_clone_table_section ());
6050 	  assemble_align (POINTER_SIZE);
6051 	  switched = true;
6052 	}
6053 
6054       assemble_integer (XEXP (DECL_RTL (src), 0),
6055 			POINTER_SIZE_UNITS, POINTER_SIZE, 1);
6056       assemble_integer (XEXP (DECL_RTL (dst), 0),
6057 			POINTER_SIZE_UNITS, POINTER_SIZE, 1);
6058     }
6059 }
6060 
6061 /* Provide a default for the tm_clone_table section.  */
6062 
6063 section *
default_clone_table_section(void)6064 default_clone_table_section (void)
6065 {
6066   return get_named_section (NULL, ".tm_clone_table", 3);
6067 }
6068 
6069 /* Helper comparison function for qsorting by the DECL_UID stored in
6070    alias_pair->emitted_diags.  */
6071 
6072 static int
tm_alias_pair_cmp(const void * x,const void * y)6073 tm_alias_pair_cmp (const void *x, const void *y)
6074 {
6075   const tm_alias_pair *p1 = (const tm_alias_pair *) x;
6076   const tm_alias_pair *p2 = (const tm_alias_pair *) y;
6077   if (p1->uid < p2->uid)
6078     return -1;
6079   if (p1->uid > p2->uid)
6080     return 1;
6081   return 0;
6082 }
6083 
6084 void
finish_tm_clone_pairs(void)6085 finish_tm_clone_pairs (void)
6086 {
6087   vec<tm_alias_pair> tm_alias_pairs = vNULL;
6088 
6089   if (tm_clone_hash == NULL)
6090     return;
6091 
6092   /* We need a determenistic order for the .tm_clone_table, otherwise
6093      we will get bootstrap comparison failures, so dump the hash table
6094      to a vector, sort it, and dump the vector.  */
6095 
6096   /* Dump the hashtable to a vector.  */
6097   tree_map *map;
6098   hash_table<tm_clone_hasher>::iterator iter;
6099   FOR_EACH_HASH_TABLE_ELEMENT (*tm_clone_hash, map, tree_map *, iter)
6100     {
6101       tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
6102       tm_alias_pairs.safe_push (p);
6103     }
6104   /* Sort it.  */
6105   tm_alias_pairs.qsort (tm_alias_pair_cmp);
6106 
6107   /* Dump it.  */
6108   dump_tm_clone_pairs (tm_alias_pairs);
6109 
6110   tm_clone_hash->empty ();
6111   tm_clone_hash = NULL;
6112   tm_alias_pairs.release ();
6113 }
6114 
6115 
6116 /* Emit an assembler directive to set symbol for DECL visibility to
6117    the visibility type VIS, which must not be VISIBILITY_DEFAULT.  */
6118 
6119 void
default_assemble_visibility(tree decl ATTRIBUTE_UNUSED,int vis ATTRIBUTE_UNUSED)6120 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
6121 			     int vis ATTRIBUTE_UNUSED)
6122 {
6123 #ifdef HAVE_GAS_HIDDEN
6124   static const char * const visibility_types[] = {
6125     NULL, "protected", "hidden", "internal"
6126   };
6127 
6128   const char *name, *type;
6129   tree id;
6130 
6131   id = DECL_ASSEMBLER_NAME (decl);
6132   ultimate_transparent_alias_target (&id);
6133   name = IDENTIFIER_POINTER (id);
6134 
6135   type = visibility_types[vis];
6136 
6137   fprintf (asm_out_file, "\t.%s\t", type);
6138   assemble_name (asm_out_file, name);
6139   fprintf (asm_out_file, "\n");
6140 #else
6141   if (!DECL_ARTIFICIAL (decl))
6142     warning (OPT_Wattributes, "visibility attribute not supported "
6143 	     "in this configuration; ignored");
6144 #endif
6145 }
6146 
6147 /* A helper function to call assemble_visibility when needed for a decl.  */
6148 
6149 int
maybe_assemble_visibility(tree decl)6150 maybe_assemble_visibility (tree decl)
6151 {
6152   enum symbol_visibility vis = DECL_VISIBILITY (decl);
6153 
6154   if (TREE_CODE (decl) == FUNCTION_DECL
6155       && cgraph_node::get (decl)
6156       && cgraph_node::get (decl)->instrumentation_clone
6157       && cgraph_node::get (decl)->instrumented_version)
6158     vis = DECL_VISIBILITY (cgraph_node::get (decl)->instrumented_version->decl);
6159 
6160   if (vis != VISIBILITY_DEFAULT)
6161     {
6162       targetm.asm_out.assemble_visibility (decl, vis);
6163       return 1;
6164     }
6165   else
6166     return 0;
6167 }
6168 
6169 /* Returns 1 if the target configuration supports defining public symbols
6170    so that one of them will be chosen at link time instead of generating a
6171    multiply-defined symbol error, whether through the use of weak symbols or
6172    a target-specific mechanism for having duplicates discarded.  */
6173 
6174 int
supports_one_only(void)6175 supports_one_only (void)
6176 {
6177   if (SUPPORTS_ONE_ONLY)
6178     return 1;
6179   return TARGET_SUPPORTS_WEAK;
6180 }
6181 
6182 /* Set up DECL as a public symbol that can be defined in multiple
6183    translation units without generating a linker error.  */
6184 
6185 void
make_decl_one_only(tree decl,tree comdat_group)6186 make_decl_one_only (tree decl, tree comdat_group)
6187 {
6188   struct symtab_node *symbol;
6189   gcc_assert (VAR_OR_FUNCTION_DECL_P (decl));
6190 
6191   TREE_PUBLIC (decl) = 1;
6192 
6193   if (VAR_P (decl))
6194     symbol = varpool_node::get_create (decl);
6195   else
6196     symbol = cgraph_node::get_create (decl);
6197 
6198   if (SUPPORTS_ONE_ONLY)
6199     {
6200 #ifdef MAKE_DECL_ONE_ONLY
6201       MAKE_DECL_ONE_ONLY (decl);
6202 #endif
6203       symbol->set_comdat_group (comdat_group);
6204     }
6205   else if (VAR_P (decl)
6206            && (DECL_INITIAL (decl) == 0
6207 	       || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
6208     DECL_COMMON (decl) = 1;
6209   else
6210     {
6211       gcc_assert (TARGET_SUPPORTS_WEAK);
6212       DECL_WEAK (decl) = 1;
6213     }
6214 }
6215 
6216 void
init_varasm_once(void)6217 init_varasm_once (void)
6218 {
6219   section_htab = hash_table<section_hasher>::create_ggc (31);
6220   object_block_htab = hash_table<object_block_hasher>::create_ggc (31);
6221   const_desc_htab = hash_table<tree_descriptor_hasher>::create_ggc (1009);
6222 
6223   shared_constant_pool = create_constant_pool ();
6224 
6225 #ifdef TEXT_SECTION_ASM_OP
6226   text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
6227 				      TEXT_SECTION_ASM_OP);
6228 #endif
6229 
6230 #ifdef DATA_SECTION_ASM_OP
6231   data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
6232 				      DATA_SECTION_ASM_OP);
6233 #endif
6234 
6235 #ifdef SDATA_SECTION_ASM_OP
6236   sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
6237 				       SDATA_SECTION_ASM_OP);
6238 #endif
6239 
6240 #ifdef READONLY_DATA_SECTION_ASM_OP
6241   readonly_data_section = get_unnamed_section (0, output_section_asm_op,
6242 					       READONLY_DATA_SECTION_ASM_OP);
6243 #endif
6244 
6245 #ifdef CTORS_SECTION_ASM_OP
6246   ctors_section = get_unnamed_section (0, output_section_asm_op,
6247 				       CTORS_SECTION_ASM_OP);
6248 #endif
6249 
6250 #ifdef DTORS_SECTION_ASM_OP
6251   dtors_section = get_unnamed_section (0, output_section_asm_op,
6252 				       DTORS_SECTION_ASM_OP);
6253 #endif
6254 
6255 #ifdef BSS_SECTION_ASM_OP
6256   bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6257 				     output_section_asm_op,
6258 				     BSS_SECTION_ASM_OP);
6259 #endif
6260 
6261 #ifdef SBSS_SECTION_ASM_OP
6262   sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6263 				      output_section_asm_op,
6264 				      SBSS_SECTION_ASM_OP);
6265 #endif
6266 
6267   tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6268 					   | SECTION_COMMON, emit_tls_common);
6269   lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6270 					| SECTION_COMMON, emit_local);
6271   comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6272 				       | SECTION_COMMON, emit_common);
6273 
6274 #if defined ASM_OUTPUT_ALIGNED_BSS
6275   bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
6276 					       emit_bss);
6277 #endif
6278 
6279   targetm.asm_out.init_sections ();
6280 
6281   if (readonly_data_section == NULL)
6282     readonly_data_section = text_section;
6283 
6284 #ifdef ASM_OUTPUT_EXTERNAL
6285   pending_assemble_externals_set = new hash_set<tree>;
6286 #endif
6287 }
6288 
6289 enum tls_model
decl_default_tls_model(const_tree decl)6290 decl_default_tls_model (const_tree decl)
6291 {
6292   enum tls_model kind;
6293   bool is_local;
6294 
6295   is_local = targetm.binds_local_p (decl);
6296   if (!flag_shlib)
6297     {
6298       if (is_local)
6299 	kind = TLS_MODEL_LOCAL_EXEC;
6300       else
6301 	kind = TLS_MODEL_INITIAL_EXEC;
6302     }
6303 
6304   /* Local dynamic is inefficient when we're not combining the
6305      parts of the address.  */
6306   else if (optimize && is_local)
6307     kind = TLS_MODEL_LOCAL_DYNAMIC;
6308   else
6309     kind = TLS_MODEL_GLOBAL_DYNAMIC;
6310   if (kind < flag_tls_default)
6311     kind = flag_tls_default;
6312 
6313   return kind;
6314 }
6315 
6316 /* Select a set of attributes for section NAME based on the properties
6317    of DECL and whether or not RELOC indicates that DECL's initializer
6318    might contain runtime relocations.
6319 
6320    We make the section read-only and executable for a function decl,
6321    read-only for a const data decl, and writable for a non-const data decl.  */
6322 
6323 unsigned int
default_section_type_flags(tree decl,const char * name,int reloc)6324 default_section_type_flags (tree decl, const char *name, int reloc)
6325 {
6326   unsigned int flags;
6327 
6328   if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6329     flags = SECTION_CODE;
6330   else if (decl)
6331     {
6332       enum section_category category
6333 	= categorize_decl_for_section (decl, reloc);
6334       if (decl_readonly_section_1 (category))
6335 	flags = 0;
6336       else if (category == SECCAT_DATA_REL_RO
6337 	       || category == SECCAT_DATA_REL_RO_LOCAL)
6338 	flags = SECTION_WRITE | SECTION_RELRO;
6339       else
6340 	flags = SECTION_WRITE;
6341     }
6342   else
6343     {
6344       flags = SECTION_WRITE;
6345       if (strcmp (name, ".data.rel.ro") == 0
6346 	  || strcmp (name, ".data.rel.ro.local") == 0)
6347 	flags |= SECTION_RELRO;
6348     }
6349 
6350   if (decl && DECL_P (decl) && DECL_COMDAT_GROUP (decl))
6351     flags |= SECTION_LINKONCE;
6352 
6353   if (strcmp (name, ".vtable_map_vars") == 0)
6354     flags |= SECTION_LINKONCE;
6355 
6356   if (decl && VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6357     flags |= SECTION_TLS | SECTION_WRITE;
6358 
6359   if (strcmp (name, ".bss") == 0
6360       || strncmp (name, ".bss.", 5) == 0
6361       || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6362       || strcmp (name, ".persistent.bss") == 0
6363       || strcmp (name, ".sbss") == 0
6364       || strncmp (name, ".sbss.", 6) == 0
6365       || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6366     flags |= SECTION_BSS;
6367 
6368   if (strcmp (name, ".tdata") == 0
6369       || strncmp (name, ".tdata.", 7) == 0
6370       || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6371     flags |= SECTION_TLS;
6372 
6373   if (strcmp (name, ".tbss") == 0
6374       || strncmp (name, ".tbss.", 6) == 0
6375       || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6376     flags |= SECTION_TLS | SECTION_BSS;
6377 
6378   /* Various sections have special ELF types that the assembler will
6379      assign by default based on the name.  They are neither SHT_PROGBITS
6380      nor SHT_NOBITS, so when changing sections we don't want to print a
6381      section type (@progbits or @nobits).  Rather than duplicating the
6382      assembler's knowledge of what those special name patterns are, just
6383      let the assembler choose the type if we don't know a specific
6384      reason to set it to something other than the default.  SHT_PROGBITS
6385      is the default for sections whose name is not specially known to
6386      the assembler, so it does no harm to leave the choice to the
6387      assembler when @progbits is the best thing we know to use.  If
6388      someone is silly enough to emit code or TLS variables to one of
6389      these sections, then don't handle them specially.
6390 
6391      default_elf_asm_named_section (below) handles the BSS, TLS, ENTSIZE, and
6392      LINKONCE cases when NOTYPE is not set, so leave those to its logic.  */
6393   if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS | SECTION_ENTSIZE))
6394       && !(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE)))
6395     flags |= SECTION_NOTYPE;
6396 
6397   return flags;
6398 }
6399 
6400 /* Return true if the target supports some form of global BSS,
6401    either through bss_noswitch_section, or by selecting a BSS
6402    section in TARGET_ASM_SELECT_SECTION.  */
6403 
6404 bool
have_global_bss_p(void)6405 have_global_bss_p (void)
6406 {
6407   return bss_noswitch_section || targetm.have_switchable_bss_sections;
6408 }
6409 
6410 /* Output assembly to switch to section NAME with attribute FLAGS.
6411    Four variants for common object file formats.  */
6412 
6413 void
default_no_named_section(const char * name ATTRIBUTE_UNUSED,unsigned int flags ATTRIBUTE_UNUSED,tree decl ATTRIBUTE_UNUSED)6414 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6415 			  unsigned int flags ATTRIBUTE_UNUSED,
6416 			  tree decl ATTRIBUTE_UNUSED)
6417 {
6418   /* Some object formats don't support named sections at all.  The
6419      front-end should already have flagged this as an error.  */
6420   gcc_unreachable ();
6421 }
6422 
6423 #ifndef TLS_SECTION_ASM_FLAG
6424 #define TLS_SECTION_ASM_FLAG 'T'
6425 #endif
6426 
6427 void
default_elf_asm_named_section(const char * name,unsigned int flags,tree decl)6428 default_elf_asm_named_section (const char *name, unsigned int flags,
6429 			       tree decl)
6430 {
6431   char flagchars[11], *f = flagchars;
6432   unsigned int numeric_value = 0;
6433 
6434   /* If we have already declared this section, we can use an
6435      abbreviated form to switch back to it -- unless this section is
6436      part of a COMDAT groups, in which case GAS requires the full
6437      declaration every time.  */
6438   if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6439       && (flags & SECTION_DECLARED))
6440     {
6441       fprintf (asm_out_file, "\t.section\t%s\n", name);
6442       return;
6443     }
6444 
6445   /* If we have a machine specific flag, then use the numeric value to pass
6446      this on to GAS.  */
6447   if (targetm.asm_out.elf_flags_numeric (flags, &numeric_value))
6448       snprintf (f, sizeof (flagchars), "0x%08x", numeric_value);
6449   else
6450     {
6451       if (!(flags & SECTION_DEBUG))
6452 	*f++ = 'a';
6453 #if defined (HAVE_GAS_SECTION_EXCLUDE) && HAVE_GAS_SECTION_EXCLUDE == 1
6454       if (flags & SECTION_EXCLUDE)
6455 	*f++ = 'e';
6456 #endif
6457       if (flags & SECTION_WRITE)
6458 	*f++ = 'w';
6459       if (flags & SECTION_CODE)
6460 	*f++ = 'x';
6461       if (flags & SECTION_SMALL)
6462 	*f++ = 's';
6463       if (flags & SECTION_MERGE)
6464 	*f++ = 'M';
6465       if (flags & SECTION_STRINGS)
6466 	*f++ = 'S';
6467       if (flags & SECTION_TLS)
6468 	*f++ = TLS_SECTION_ASM_FLAG;
6469       if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6470 	*f++ = 'G';
6471 #ifdef MACH_DEP_SECTION_ASM_FLAG
6472       if (flags & SECTION_MACH_DEP)
6473 	*f++ = MACH_DEP_SECTION_ASM_FLAG;
6474 #endif
6475       *f = '\0';
6476     }
6477 
6478   fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6479 
6480   /* default_section_type_flags (above) knows which flags need special
6481      handling here, and sets NOTYPE when none of these apply so that the
6482      assembler's logic for default types can apply to user-chosen
6483      section names.  */
6484   if (!(flags & SECTION_NOTYPE))
6485     {
6486       const char *type;
6487       const char *format;
6488 
6489       if (flags & SECTION_BSS)
6490 	type = "nobits";
6491       else
6492 	type = "progbits";
6493 
6494       format = ",@%s";
6495       /* On platforms that use "@" as the assembly comment character,
6496 	 use "%" instead.  */
6497       if (strcmp (ASM_COMMENT_START, "@") == 0)
6498 	format = ",%%%s";
6499       fprintf (asm_out_file, format, type);
6500 
6501       if (flags & SECTION_ENTSIZE)
6502 	fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6503       if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6504 	{
6505 	  if (TREE_CODE (decl) == IDENTIFIER_NODE)
6506 	    fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6507 	  else
6508 	    fprintf (asm_out_file, ",%s,comdat",
6509 		     IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6510 	}
6511     }
6512 
6513   putc ('\n', asm_out_file);
6514 }
6515 
6516 void
default_coff_asm_named_section(const char * name,unsigned int flags,tree decl ATTRIBUTE_UNUSED)6517 default_coff_asm_named_section (const char *name, unsigned int flags,
6518 				tree decl ATTRIBUTE_UNUSED)
6519 {
6520   char flagchars[8], *f = flagchars;
6521 
6522   if (flags & SECTION_WRITE)
6523     *f++ = 'w';
6524   if (flags & SECTION_CODE)
6525     *f++ = 'x';
6526   *f = '\0';
6527 
6528   fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6529 }
6530 
6531 void
default_pe_asm_named_section(const char * name,unsigned int flags,tree decl)6532 default_pe_asm_named_section (const char *name, unsigned int flags,
6533 			      tree decl)
6534 {
6535   default_coff_asm_named_section (name, flags, decl);
6536 
6537   if (flags & SECTION_LINKONCE)
6538     {
6539       /* Functions may have been compiled at various levels of
6540          optimization so we can't use `same_size' here.
6541          Instead, have the linker pick one.  */
6542       fprintf (asm_out_file, "\t.linkonce %s\n",
6543 	       (flags & SECTION_CODE ? "discard" : "same_size"));
6544     }
6545 }
6546 
6547 /* The lame default section selector.  */
6548 
6549 section *
default_select_section(tree decl,int reloc,unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)6550 default_select_section (tree decl, int reloc,
6551 			unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6552 {
6553   if (DECL_P (decl))
6554     {
6555       if (decl_readonly_section (decl, reloc))
6556 	return readonly_data_section;
6557     }
6558   else if (TREE_CODE (decl) == CONSTRUCTOR)
6559     {
6560       if (! ((flag_pic && reloc)
6561 	     || !TREE_READONLY (decl)
6562 	     || TREE_SIDE_EFFECTS (decl)
6563 	     || !TREE_CONSTANT (decl)))
6564 	return readonly_data_section;
6565     }
6566   else if (TREE_CODE (decl) == STRING_CST)
6567     return readonly_data_section;
6568   else if (! (flag_pic && reloc))
6569     return readonly_data_section;
6570 
6571   return data_section;
6572 }
6573 
6574 enum section_category
categorize_decl_for_section(const_tree decl,int reloc)6575 categorize_decl_for_section (const_tree decl, int reloc)
6576 {
6577   enum section_category ret;
6578 
6579   if (TREE_CODE (decl) == FUNCTION_DECL)
6580     return SECCAT_TEXT;
6581   else if (TREE_CODE (decl) == STRING_CST)
6582     {
6583       if ((flag_sanitize & SANITIZE_ADDRESS)
6584 	  && asan_protect_global (CONST_CAST_TREE (decl)))
6585       /* or !flag_merge_constants */
6586         return SECCAT_RODATA;
6587       else
6588 	return SECCAT_RODATA_MERGE_STR;
6589     }
6590   else if (VAR_P (decl))
6591     {
6592       tree d = CONST_CAST_TREE (decl);
6593       if (bss_initializer_p (decl))
6594 	ret = SECCAT_BSS;
6595       else if (! TREE_READONLY (decl)
6596 	       || TREE_SIDE_EFFECTS (decl)
6597 	       || (DECL_INITIAL (decl)
6598 		   && ! TREE_CONSTANT (DECL_INITIAL (decl))))
6599 	{
6600 	  /* Here the reloc_rw_mask is not testing whether the section should
6601 	     be read-only or not, but whether the dynamic link will have to
6602 	     do something.  If so, we wish to segregate the data in order to
6603 	     minimize cache misses inside the dynamic linker.  */
6604 	  if (reloc & targetm.asm_out.reloc_rw_mask ())
6605 	    ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6606 	  else
6607 	    ret = SECCAT_DATA;
6608 	}
6609       else if (reloc & targetm.asm_out.reloc_rw_mask ())
6610 	ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6611       else if (reloc || flag_merge_constants < 2
6612 	       || ((flag_sanitize & SANITIZE_ADDRESS)
6613 		   /* PR 81697: for architectures that use section anchors we
6614 		      need to ignore DECL_RTL_SET_P (decl) for string constants
6615 		      inside this asan_protect_global call because otherwise
6616 		      we'll wrongly put them into SECCAT_RODATA_MERGE_CONST
6617 		      section, set DECL_RTL (decl) later on and add DECL to
6618 		      protected globals via successive asan_protect_global
6619 		      calls.  In this scenario we'll end up with wrong
6620 		      alignment of these strings at runtime and possible ASan
6621 		      false positives.  */
6622 		   && asan_protect_global (d, use_object_blocks_p ()
6623 					      && use_blocks_for_decl_p (d))))
6624 	/* C and C++ don't allow different variables to share the same
6625 	   location.  -fmerge-all-constants allows even that (at the
6626 	   expense of not conforming).  */
6627 	ret = SECCAT_RODATA;
6628       else if (DECL_INITIAL (decl)
6629 	       && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6630 	ret = SECCAT_RODATA_MERGE_STR_INIT;
6631       else
6632 	ret = SECCAT_RODATA_MERGE_CONST;
6633     }
6634   else if (TREE_CODE (decl) == CONSTRUCTOR)
6635     {
6636       if ((reloc & targetm.asm_out.reloc_rw_mask ())
6637 	  || TREE_SIDE_EFFECTS (decl)
6638 	  || ! TREE_CONSTANT (decl))
6639 	ret = SECCAT_DATA;
6640       else
6641 	ret = SECCAT_RODATA;
6642     }
6643   else
6644     ret = SECCAT_RODATA;
6645 
6646   /* There are no read-only thread-local sections.  */
6647   if (VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6648     {
6649       /* Note that this would be *just* SECCAT_BSS, except that there's
6650 	 no concept of a read-only thread-local-data section.  */
6651       if (ret == SECCAT_BSS
6652 	  || DECL_INITIAL (decl) == NULL
6653 	  || (flag_zero_initialized_in_bss
6654 	      && initializer_zerop (DECL_INITIAL (decl))))
6655 	ret = SECCAT_TBSS;
6656       else
6657 	ret = SECCAT_TDATA;
6658     }
6659 
6660   /* If the target uses small data sections, select it.  */
6661   else if (targetm.in_small_data_p (decl))
6662     {
6663       if (ret == SECCAT_BSS)
6664 	ret = SECCAT_SBSS;
6665       else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6666 	ret = SECCAT_SRODATA;
6667       else
6668 	ret = SECCAT_SDATA;
6669     }
6670 
6671   return ret;
6672 }
6673 
6674 static bool
decl_readonly_section_1(enum section_category category)6675 decl_readonly_section_1 (enum section_category category)
6676 {
6677   switch (category)
6678     {
6679     case SECCAT_RODATA:
6680     case SECCAT_RODATA_MERGE_STR:
6681     case SECCAT_RODATA_MERGE_STR_INIT:
6682     case SECCAT_RODATA_MERGE_CONST:
6683     case SECCAT_SRODATA:
6684       return true;
6685     default:
6686       return false;
6687     }
6688 }
6689 
6690 bool
decl_readonly_section(const_tree decl,int reloc)6691 decl_readonly_section (const_tree decl, int reloc)
6692 {
6693   return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6694 }
6695 
6696 /* Select a section based on the above categorization.  */
6697 
6698 section *
default_elf_select_section(tree decl,int reloc,unsigned HOST_WIDE_INT align)6699 default_elf_select_section (tree decl, int reloc,
6700 			    unsigned HOST_WIDE_INT align)
6701 {
6702   const char *sname;
6703   switch (categorize_decl_for_section (decl, reloc))
6704     {
6705     case SECCAT_TEXT:
6706       /* We're not supposed to be called on FUNCTION_DECLs.  */
6707       gcc_unreachable ();
6708     case SECCAT_RODATA:
6709       return readonly_data_section;
6710     case SECCAT_RODATA_MERGE_STR:
6711       return mergeable_string_section (decl, align, 0);
6712     case SECCAT_RODATA_MERGE_STR_INIT:
6713       return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6714     case SECCAT_RODATA_MERGE_CONST:
6715       return mergeable_constant_section (DECL_MODE (decl), align, 0);
6716     case SECCAT_SRODATA:
6717       sname = ".sdata2";
6718       break;
6719     case SECCAT_DATA:
6720       return data_section;
6721     case SECCAT_DATA_REL:
6722       sname = ".data.rel";
6723       break;
6724     case SECCAT_DATA_REL_LOCAL:
6725       sname = ".data.rel.local";
6726       break;
6727     case SECCAT_DATA_REL_RO:
6728       sname = ".data.rel.ro";
6729       break;
6730     case SECCAT_DATA_REL_RO_LOCAL:
6731       sname = ".data.rel.ro.local";
6732       break;
6733     case SECCAT_SDATA:
6734       sname = ".sdata";
6735       break;
6736     case SECCAT_TDATA:
6737       sname = ".tdata";
6738       break;
6739     case SECCAT_BSS:
6740       if (bss_section)
6741 	return bss_section;
6742       sname = ".bss";
6743       break;
6744     case SECCAT_SBSS:
6745       sname = ".sbss";
6746       break;
6747     case SECCAT_TBSS:
6748       sname = ".tbss";
6749       break;
6750     default:
6751       gcc_unreachable ();
6752     }
6753 
6754   return get_named_section (decl, sname, reloc);
6755 }
6756 
6757 /* Construct a unique section name based on the decl name and the
6758    categorization performed above.  */
6759 
6760 void
default_unique_section(tree decl,int reloc)6761 default_unique_section (tree decl, int reloc)
6762 {
6763   /* We only need to use .gnu.linkonce if we don't have COMDAT groups.  */
6764   bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6765   const char *prefix, *name, *linkonce;
6766   char *string;
6767   tree id;
6768 
6769   switch (categorize_decl_for_section (decl, reloc))
6770     {
6771     case SECCAT_TEXT:
6772       prefix = one_only ? ".t" : ".text";
6773       break;
6774     case SECCAT_RODATA:
6775     case SECCAT_RODATA_MERGE_STR:
6776     case SECCAT_RODATA_MERGE_STR_INIT:
6777     case SECCAT_RODATA_MERGE_CONST:
6778       prefix = one_only ? ".r" : ".rodata";
6779       break;
6780     case SECCAT_SRODATA:
6781       prefix = one_only ? ".s2" : ".sdata2";
6782       break;
6783     case SECCAT_DATA:
6784       prefix = one_only ? ".d" : ".data";
6785       break;
6786     case SECCAT_DATA_REL:
6787       prefix = one_only ? ".d.rel" : ".data.rel";
6788       break;
6789     case SECCAT_DATA_REL_LOCAL:
6790       prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6791       break;
6792     case SECCAT_DATA_REL_RO:
6793       prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6794       break;
6795     case SECCAT_DATA_REL_RO_LOCAL:
6796       prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6797       break;
6798     case SECCAT_SDATA:
6799       prefix = one_only ? ".s" : ".sdata";
6800       break;
6801     case SECCAT_BSS:
6802       prefix = one_only ? ".b" : ".bss";
6803       break;
6804     case SECCAT_SBSS:
6805       prefix = one_only ? ".sb" : ".sbss";
6806       break;
6807     case SECCAT_TDATA:
6808       prefix = one_only ? ".td" : ".tdata";
6809       break;
6810     case SECCAT_TBSS:
6811       prefix = one_only ? ".tb" : ".tbss";
6812       break;
6813     default:
6814       gcc_unreachable ();
6815     }
6816 
6817   id = DECL_ASSEMBLER_NAME (decl);
6818   ultimate_transparent_alias_target (&id);
6819   name = IDENTIFIER_POINTER (id);
6820   name = targetm.strip_name_encoding (name);
6821 
6822   /* If we're using one_only, then there needs to be a .gnu.linkonce
6823      prefix to the section name.  */
6824   linkonce = one_only ? ".gnu.linkonce" : "";
6825 
6826   string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6827 
6828   set_decl_section_name (decl, string);
6829 }
6830 
6831 /* Subroutine of compute_reloc_for_rtx for leaf rtxes.  */
6832 
6833 static int
compute_reloc_for_rtx_1(const_rtx x)6834 compute_reloc_for_rtx_1 (const_rtx x)
6835 {
6836   switch (GET_CODE (x))
6837     {
6838     case SYMBOL_REF:
6839       return SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6840     case LABEL_REF:
6841       return 1;
6842     default:
6843       return 0;
6844     }
6845 }
6846 
6847 /* Like compute_reloc_for_constant, except for an RTX.  The return value
6848    is a mask for which bit 1 indicates a global relocation, and bit 0
6849    indicates a local relocation.  */
6850 
6851 static int
compute_reloc_for_rtx(const_rtx x)6852 compute_reloc_for_rtx (const_rtx x)
6853 {
6854   switch (GET_CODE (x))
6855     {
6856     case SYMBOL_REF:
6857     case LABEL_REF:
6858       return compute_reloc_for_rtx_1 (x);
6859 
6860     case CONST:
6861       {
6862 	int reloc = 0;
6863 	subrtx_iterator::array_type array;
6864 	FOR_EACH_SUBRTX (iter, array, x, ALL)
6865 	  reloc |= compute_reloc_for_rtx_1 (*iter);
6866 	return reloc;
6867       }
6868 
6869     default:
6870       return 0;
6871     }
6872 }
6873 
6874 section *
default_select_rtx_section(machine_mode mode ATTRIBUTE_UNUSED,rtx x,unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)6875 default_select_rtx_section (machine_mode mode ATTRIBUTE_UNUSED,
6876 			    rtx x,
6877 			    unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6878 {
6879   if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6880     return data_section;
6881   else
6882     return readonly_data_section;
6883 }
6884 
6885 section *
default_elf_select_rtx_section(machine_mode mode,rtx x,unsigned HOST_WIDE_INT align)6886 default_elf_select_rtx_section (machine_mode mode, rtx x,
6887 				unsigned HOST_WIDE_INT align)
6888 {
6889   int reloc = compute_reloc_for_rtx (x);
6890 
6891   /* ??? Handle small data here somehow.  */
6892 
6893   if (reloc & targetm.asm_out.reloc_rw_mask ())
6894     {
6895       if (reloc == 1)
6896 	return get_named_section (NULL, ".data.rel.ro.local", 1);
6897       else
6898 	return get_named_section (NULL, ".data.rel.ro", 3);
6899     }
6900 
6901   return mergeable_constant_section (mode, align, 0);
6902 }
6903 
6904 /* Set the generally applicable flags on the SYMBOL_REF for EXP.  */
6905 
6906 void
default_encode_section_info(tree decl,rtx rtl,int first ATTRIBUTE_UNUSED)6907 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6908 {
6909   rtx symbol;
6910   int flags;
6911 
6912   /* Careful not to prod global register variables.  */
6913   if (!MEM_P (rtl))
6914     return;
6915   symbol = XEXP (rtl, 0);
6916   if (GET_CODE (symbol) != SYMBOL_REF)
6917     return;
6918 
6919   flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6920   if (TREE_CODE (decl) == FUNCTION_DECL)
6921     flags |= SYMBOL_FLAG_FUNCTION;
6922   if (targetm.binds_local_p (decl))
6923     flags |= SYMBOL_FLAG_LOCAL;
6924   if (VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6925     flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6926   else if (targetm.in_small_data_p (decl))
6927     flags |= SYMBOL_FLAG_SMALL;
6928   /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names?  Without
6929      being PUBLIC, the thing *must* be defined in this translation unit.
6930      Prevent this buglet from being propagated into rtl code as well.  */
6931   if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6932     flags |= SYMBOL_FLAG_EXTERNAL;
6933 
6934   SYMBOL_REF_FLAGS (symbol) = flags;
6935 }
6936 
6937 /* By default, we do nothing for encode_section_info, so we need not
6938    do anything but discard the '*' marker.  */
6939 
6940 const char *
default_strip_name_encoding(const char * str)6941 default_strip_name_encoding (const char *str)
6942 {
6943   return str + (*str == '*');
6944 }
6945 
6946 #ifdef ASM_OUTPUT_DEF
6947 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR.  Define the
6948    anchor relative to ".", the current section position.  */
6949 
6950 void
default_asm_output_anchor(rtx symbol)6951 default_asm_output_anchor (rtx symbol)
6952 {
6953   char buffer[100];
6954 
6955   sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6956 	   SYMBOL_REF_BLOCK_OFFSET (symbol));
6957   ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6958 }
6959 #endif
6960 
6961 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P.  */
6962 
6963 bool
default_use_anchors_for_symbol_p(const_rtx symbol)6964 default_use_anchors_for_symbol_p (const_rtx symbol)
6965 {
6966   section *sect;
6967   tree decl;
6968 
6969   /* Don't use anchors for mergeable sections.  The linker might move
6970      the objects around.  */
6971   sect = SYMBOL_REF_BLOCK (symbol)->sect;
6972   if (sect->common.flags & SECTION_MERGE)
6973     return false;
6974 
6975   /* Don't use anchors for small data sections.  The small data register
6976      acts as an anchor for such sections.  */
6977   if (sect->common.flags & SECTION_SMALL)
6978     return false;
6979 
6980   decl = SYMBOL_REF_DECL (symbol);
6981   if (decl && DECL_P (decl))
6982     {
6983       /* Don't use section anchors for decls that might be defined or
6984 	 usurped by other modules.  */
6985       if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6986 	return false;
6987 
6988       /* Don't use section anchors for decls that will be placed in a
6989 	 small data section.  */
6990       /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6991 	 one above.  The problem is that we only use SECTION_SMALL for
6992 	 sections that should be marked as small in the section directive.  */
6993       if (targetm.in_small_data_p (decl))
6994 	return false;
6995 
6996       /* Don't use section anchors for decls that won't fit inside a single
6997 	 anchor range to reduce the amount of instructions required to refer
6998 	 to the entire declaration.  */
6999       if (DECL_SIZE_UNIT (decl) == NULL_TREE
7000 	  || !tree_fits_uhwi_p (DECL_SIZE_UNIT (decl))
7001 	  || (tree_to_uhwi (DECL_SIZE_UNIT (decl))
7002 	      >= (unsigned HOST_WIDE_INT) targetm.max_anchor_offset))
7003 	return false;
7004 
7005     }
7006   return true;
7007 }
7008 
7009 /* Return true when RESOLUTION indicate that symbol will be bound to the
7010    definition provided by current .o file.  */
7011 
7012 static bool
resolution_to_local_definition_p(enum ld_plugin_symbol_resolution resolution)7013 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
7014 {
7015   return (resolution == LDPR_PREVAILING_DEF
7016 	  || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
7017 	  || resolution == LDPR_PREVAILING_DEF_IRONLY);
7018 }
7019 
7020 /* Return true when RESOLUTION indicate that symbol will be bound locally
7021    within current executable or DSO.  */
7022 
7023 static bool
resolution_local_p(enum ld_plugin_symbol_resolution resolution)7024 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
7025 {
7026   return (resolution == LDPR_PREVAILING_DEF
7027 	  || resolution == LDPR_PREVAILING_DEF_IRONLY
7028 	  || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
7029 	  || resolution == LDPR_PREEMPTED_REG
7030 	  || resolution == LDPR_PREEMPTED_IR
7031 	  || resolution == LDPR_RESOLVED_IR
7032 	  || resolution == LDPR_RESOLVED_EXEC);
7033 }
7034 
7035 /* COMMON_LOCAL_P is true means that the linker can guarantee that an
7036    uninitialized common symbol in the executable will still be defined
7037    (through COPY relocation) in the executable.  */
7038 
7039 bool
default_binds_local_p_3(const_tree exp,bool shlib,bool weak_dominate,bool extern_protected_data,bool common_local_p)7040 default_binds_local_p_3 (const_tree exp, bool shlib, bool weak_dominate,
7041 			 bool extern_protected_data, bool common_local_p)
7042 {
7043   /* A non-decl is an entry in the constant pool.  */
7044   if (!DECL_P (exp))
7045     return true;
7046 
7047   /* Weakrefs may not bind locally, even though the weakref itself is always
7048      static and therefore local.  Similarly, the resolver for ifunc functions
7049      might resolve to a non-local function.
7050      FIXME: We can resolve the weakref case more curefuly by looking at the
7051      weakref alias.  */
7052   if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
7053       || (TREE_CODE (exp) == FUNCTION_DECL
7054 	  && cgraph_node::get (exp)
7055 	  && cgraph_node::get (exp)->ifunc_resolver))
7056     return false;
7057 
7058   /* Static variables are always local.  */
7059   if (! TREE_PUBLIC (exp))
7060     return true;
7061 
7062   /* With resolution file in hand, take look into resolutions.
7063      We can't just return true for resolved_locally symbols,
7064      because dynamic linking might overwrite symbols
7065      in shared libraries.  */
7066   bool resolved_locally = false;
7067 
7068   bool uninited_common = (DECL_COMMON (exp)
7069 			  && (DECL_INITIAL (exp) == NULL
7070 			      || (!in_lto_p
7071 				  && DECL_INITIAL (exp) == error_mark_node)));
7072 
7073   /* A non-external variable is defined locally only if it isn't
7074      uninitialized COMMON variable or common_local_p is true.  */
7075   bool defined_locally = (!DECL_EXTERNAL (exp)
7076 			  && (!uninited_common || common_local_p));
7077   if (symtab_node *node = symtab_node::get (exp))
7078     {
7079       if (node->in_other_partition)
7080 	defined_locally = true;
7081       if (node->can_be_discarded_p ())
7082 	;
7083       else if (resolution_to_local_definition_p (node->resolution))
7084 	defined_locally = resolved_locally = true;
7085       else if (resolution_local_p (node->resolution))
7086 	resolved_locally = true;
7087     }
7088   if (defined_locally && weak_dominate && !shlib)
7089     resolved_locally = true;
7090 
7091   /* Undefined weak symbols are never defined locally.  */
7092   if (DECL_WEAK (exp) && !defined_locally)
7093     return false;
7094 
7095   /* A symbol is local if the user has said explicitly that it will be,
7096      or if we have a definition for the symbol.  We cannot infer visibility
7097      for undefined symbols.  */
7098   if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT
7099       && (TREE_CODE (exp) == FUNCTION_DECL
7100 	  || !extern_protected_data
7101 	  || DECL_VISIBILITY (exp) != VISIBILITY_PROTECTED)
7102       && (DECL_VISIBILITY_SPECIFIED (exp) || defined_locally))
7103     return true;
7104 
7105   /* If PIC, then assume that any global name can be overridden by
7106      symbols resolved from other modules.  */
7107   if (shlib)
7108     return false;
7109 
7110   /* Variables defined outside this object might not be local.  */
7111   if (DECL_EXTERNAL (exp) && !resolved_locally)
7112     return false;
7113 
7114   /* Non-dominant weak symbols are not defined locally.  */
7115   if (DECL_WEAK (exp) && !resolved_locally)
7116     return false;
7117 
7118   /* Uninitialized COMMON variable may be unified with symbols
7119      resolved from other modules.  */
7120   if (uninited_common && !resolved_locally)
7121     return false;
7122 
7123   /* Otherwise we're left with initialized (or non-common) global data
7124      which is of necessity defined locally.  */
7125   return true;
7126 }
7127 
7128 /* Assume ELF-ish defaults, since that's pretty much the most liberal
7129    wrt cross-module name binding.  */
7130 
7131 bool
default_binds_local_p(const_tree exp)7132 default_binds_local_p (const_tree exp)
7133 {
7134   return default_binds_local_p_3 (exp, flag_shlib != 0, true, false, false);
7135 }
7136 
7137 /* Similar to default_binds_local_p, but common symbol may be local and
7138    extern protected data is non-local.  */
7139 
7140 bool
default_binds_local_p_2(const_tree exp)7141 default_binds_local_p_2 (const_tree exp)
7142 {
7143   return default_binds_local_p_3 (exp, flag_shlib != 0, true, true,
7144 				  !flag_pic);
7145 }
7146 
7147 bool
default_binds_local_p_1(const_tree exp,int shlib)7148 default_binds_local_p_1 (const_tree exp, int shlib)
7149 {
7150   return default_binds_local_p_3 (exp, shlib != 0, false, false, false);
7151 }
7152 
7153 /* Return true when references to DECL must bind to current definition in
7154    final executable.
7155 
7156    The condition is usually equivalent to whether the function binds to the
7157    current module (shared library or executable), that is to binds_local_p.
7158    We use this fact to avoid need for another target hook and implement
7159    the logic using binds_local_p and just special cases where
7160    decl_binds_to_current_def_p is stronger than binds_local_p.  In particular
7161    the weak definitions (that can be overwritten at linktime by other
7162    definition from different object file) and when resolution info is available
7163    we simply use the knowledge passed to us by linker plugin.  */
7164 bool
decl_binds_to_current_def_p(const_tree decl)7165 decl_binds_to_current_def_p (const_tree decl)
7166 {
7167   gcc_assert (DECL_P (decl));
7168   if (!targetm.binds_local_p (decl))
7169     return false;
7170   if (!TREE_PUBLIC (decl))
7171     return true;
7172 
7173   /* When resolution is available, just use it.  */
7174   if (symtab_node *node = symtab_node::get (decl))
7175     {
7176       if (node->resolution != LDPR_UNKNOWN
7177 	  && !node->can_be_discarded_p ())
7178 	return resolution_to_local_definition_p (node->resolution);
7179     }
7180 
7181   /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
7182      binds locally but still can be overwritten), DECL_COMMON (can be merged
7183      with a non-common definition somewhere in the same module) or
7184      DECL_EXTERNAL.
7185      This rely on fact that binds_local_p behave as decl_replaceable_p
7186      for all other declaration types.  */
7187   if (DECL_WEAK (decl))
7188     return false;
7189   if (DECL_COMMON (decl)
7190       && (DECL_INITIAL (decl) == NULL
7191 	  || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
7192     return false;
7193   if (DECL_EXTERNAL (decl))
7194     return false;
7195   return true;
7196 }
7197 
7198 /* A replaceable function or variable is one which may be replaced
7199    at link-time with an entirely different definition, provided that the
7200    replacement has the same type.  For example, functions declared
7201    with __attribute__((weak)) on most systems are replaceable.
7202 
7203    COMDAT functions are not replaceable, since all definitions of the
7204    function must be equivalent.  It is important that COMDAT functions
7205    not be treated as replaceable so that use of C++ template
7206    instantiations is not penalized.  */
7207 
7208 bool
decl_replaceable_p(tree decl)7209 decl_replaceable_p (tree decl)
7210 {
7211   gcc_assert (DECL_P (decl));
7212   if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
7213     return false;
7214   if (!flag_semantic_interposition
7215       && !DECL_WEAK (decl))
7216     return false;
7217   return !decl_binds_to_current_def_p (decl);
7218 }
7219 
7220 /* Default function to output code that will globalize a label.  A
7221    target must define GLOBAL_ASM_OP or provide its own function to
7222    globalize a label.  */
7223 #ifdef GLOBAL_ASM_OP
7224 void
default_globalize_label(FILE * stream,const char * name)7225 default_globalize_label (FILE * stream, const char *name)
7226 {
7227   fputs (GLOBAL_ASM_OP, stream);
7228   assemble_name (stream, name);
7229   putc ('\n', stream);
7230 }
7231 #endif /* GLOBAL_ASM_OP */
7232 
7233 /* Default function to output code that will globalize a declaration.  */
7234 void
default_globalize_decl_name(FILE * stream,tree decl)7235 default_globalize_decl_name (FILE * stream, tree decl)
7236 {
7237   const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
7238   targetm.asm_out.globalize_label (stream, name);
7239 }
7240 
7241 /* Default function to output a label for unwind information.  The
7242    default is to do nothing.  A target that needs nonlocal labels for
7243    unwind information must provide its own function to do this.  */
7244 void
default_emit_unwind_label(FILE * stream ATTRIBUTE_UNUSED,tree decl ATTRIBUTE_UNUSED,int for_eh ATTRIBUTE_UNUSED,int empty ATTRIBUTE_UNUSED)7245 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
7246 			   tree decl ATTRIBUTE_UNUSED,
7247 			   int for_eh ATTRIBUTE_UNUSED,
7248 			   int empty ATTRIBUTE_UNUSED)
7249 {
7250 }
7251 
7252 /* Default function to output a label to divide up the exception table.
7253    The default is to do nothing.  A target that needs/wants to divide
7254    up the table must provide it's own function to do this.  */
7255 void
default_emit_except_table_label(FILE * stream ATTRIBUTE_UNUSED)7256 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
7257 {
7258 }
7259 
7260 /* This is how to output an internal numbered label where PREFIX is
7261    the class of label and LABELNO is the number within the class.  */
7262 
7263 void
default_generate_internal_label(char * buf,const char * prefix,unsigned long labelno)7264 default_generate_internal_label (char *buf, const char *prefix,
7265 				 unsigned long labelno)
7266 {
7267   ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
7268 }
7269 
7270 /* This is how to output an internal numbered label where PREFIX is
7271    the class of label and LABELNO is the number within the class.  */
7272 
7273 void
default_internal_label(FILE * stream,const char * prefix,unsigned long labelno)7274 default_internal_label (FILE *stream, const char *prefix,
7275 			unsigned long labelno)
7276 {
7277   char *const buf = (char *) alloca (40 + strlen (prefix));
7278   ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
7279   ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
7280 }
7281 
7282 
7283 /* The default implementation of ASM_DECLARE_CONSTANT_NAME.  */
7284 
7285 void
default_asm_declare_constant_name(FILE * file,const char * name,const_tree exp ATTRIBUTE_UNUSED,HOST_WIDE_INT size ATTRIBUTE_UNUSED)7286 default_asm_declare_constant_name (FILE *file, const char *name,
7287 				   const_tree exp ATTRIBUTE_UNUSED,
7288 				   HOST_WIDE_INT size ATTRIBUTE_UNUSED)
7289 {
7290   assemble_label (file, name);
7291 }
7292 
7293 /* This is the default behavior at the beginning of a file.  It's
7294    controlled by two other target-hook toggles.  */
7295 void
default_file_start(void)7296 default_file_start (void)
7297 {
7298   if (targetm.asm_file_start_app_off
7299       && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
7300     fputs (ASM_APP_OFF, asm_out_file);
7301 
7302   if (targetm.asm_file_start_file_directive)
7303     {
7304       /* LTO produced units have no meaningful main_input_filename.  */
7305       if (in_lto_p)
7306 	output_file_directive (asm_out_file, "<artificial>");
7307       else
7308 	output_file_directive (asm_out_file, main_input_filename);
7309     }
7310 }
7311 
7312 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
7313    which emits a special section directive used to indicate whether or
7314    not this object file needs an executable stack.  This is primarily
7315    a GNU extension to ELF but could be used on other targets.  */
7316 
7317 int trampolines_created;
7318 
7319 void
file_end_indicate_exec_stack(void)7320 file_end_indicate_exec_stack (void)
7321 {
7322   unsigned int flags = SECTION_DEBUG;
7323   if (trampolines_created)
7324     flags |= SECTION_CODE;
7325 
7326   switch_to_section (get_section (".note.GNU-stack", flags, NULL));
7327 }
7328 
7329 /* Emit a special section directive to indicate that this object file
7330    was compiled with -fsplit-stack.  This is used to let the linker
7331    detect calls between split-stack code and non-split-stack code, so
7332    that it can modify the split-stack code to allocate a sufficiently
7333    large stack.  We emit another special section if there are any
7334    functions in this file which have the no_split_stack attribute, to
7335    prevent the linker from warning about being unable to convert the
7336    functions if they call non-split-stack code.  */
7337 
7338 void
file_end_indicate_split_stack(void)7339 file_end_indicate_split_stack (void)
7340 {
7341   if (flag_split_stack)
7342     {
7343       switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
7344 				      NULL));
7345       if (saw_no_split_stack)
7346 	switch_to_section (get_section (".note.GNU-no-split-stack",
7347 					SECTION_DEBUG, NULL));
7348     }
7349 }
7350 
7351 /* Output DIRECTIVE (a C string) followed by a newline.  This is used as
7352    a get_unnamed_section callback.  */
7353 
7354 void
output_section_asm_op(const void * directive)7355 output_section_asm_op (const void *directive)
7356 {
7357   fprintf (asm_out_file, "%s\n", (const char *) directive);
7358 }
7359 
7360 /* Emit assembly code to switch to section NEW_SECTION.  Do nothing if
7361    the current section is NEW_SECTION.  */
7362 
7363 void
switch_to_section(section * new_section)7364 switch_to_section (section *new_section)
7365 {
7366   if (in_section == new_section)
7367     return;
7368 
7369   if (new_section->common.flags & SECTION_FORGET)
7370     in_section = NULL;
7371   else
7372     in_section = new_section;
7373 
7374   switch (SECTION_STYLE (new_section))
7375     {
7376     case SECTION_NAMED:
7377       targetm.asm_out.named_section (new_section->named.name,
7378 				     new_section->named.common.flags,
7379 				     new_section->named.decl);
7380       break;
7381 
7382     case SECTION_UNNAMED:
7383       new_section->unnamed.callback (new_section->unnamed.data);
7384       break;
7385 
7386     case SECTION_NOSWITCH:
7387       gcc_unreachable ();
7388       break;
7389     }
7390 
7391   new_section->common.flags |= SECTION_DECLARED;
7392 }
7393 
7394 /* If block symbol SYMBOL has not yet been assigned an offset, place
7395    it at the end of its block.  */
7396 
7397 void
place_block_symbol(rtx symbol)7398 place_block_symbol (rtx symbol)
7399 {
7400   unsigned HOST_WIDE_INT size, mask, offset;
7401   struct constant_descriptor_rtx *desc;
7402   unsigned int alignment;
7403   struct object_block *block;
7404   tree decl;
7405 
7406   gcc_assert (SYMBOL_REF_BLOCK (symbol));
7407   if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7408     return;
7409 
7410   /* Work out the symbol's size and alignment.  */
7411   if (CONSTANT_POOL_ADDRESS_P (symbol))
7412     {
7413       desc = SYMBOL_REF_CONSTANT (symbol);
7414       alignment = desc->align;
7415       size = GET_MODE_SIZE (desc->mode);
7416     }
7417   else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7418     {
7419       decl = SYMBOL_REF_DECL (symbol);
7420       gcc_checking_assert (DECL_IN_CONSTANT_POOL (decl));
7421       alignment = DECL_ALIGN (decl);
7422       size = get_constant_size (DECL_INITIAL (decl));
7423       if ((flag_sanitize & SANITIZE_ADDRESS)
7424 	  && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7425 	  && asan_protect_global (DECL_INITIAL (decl)))
7426 	{
7427 	  size += asan_red_zone_size (size);
7428 	  alignment = MAX (alignment,
7429 			   ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7430 	}
7431     }
7432   else
7433     {
7434       struct symtab_node *snode;
7435       decl = SYMBOL_REF_DECL (symbol);
7436 
7437       snode = symtab_node::get (decl);
7438       if (snode->alias)
7439 	{
7440 	  rtx target = DECL_RTL (snode->ultimate_alias_target ()->decl);
7441 
7442 	  gcc_assert (MEM_P (target)
7443 		      && GET_CODE (XEXP (target, 0)) == SYMBOL_REF
7444 		      && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (target, 0)));
7445 	  target = XEXP (target, 0);
7446 	  place_block_symbol (target);
7447 	  SYMBOL_REF_BLOCK_OFFSET (symbol) = SYMBOL_REF_BLOCK_OFFSET (target);
7448 	  return;
7449 	}
7450       alignment = get_variable_align (decl);
7451       size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7452       if ((flag_sanitize & SANITIZE_ADDRESS)
7453 	  && asan_protect_global (decl))
7454 	{
7455 	  size += asan_red_zone_size (size);
7456 	  alignment = MAX (alignment,
7457 			   ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7458 	}
7459     }
7460 
7461   /* Calculate the object's offset from the start of the block.  */
7462   block = SYMBOL_REF_BLOCK (symbol);
7463   mask = alignment / BITS_PER_UNIT - 1;
7464   offset = (block->size + mask) & ~mask;
7465   SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7466 
7467   /* Record the block's new alignment and size.  */
7468   block->alignment = MAX (block->alignment, alignment);
7469   block->size = offset + size;
7470 
7471   vec_safe_push (block->objects, symbol);
7472 }
7473 
7474 /* Return the anchor that should be used to address byte offset OFFSET
7475    from the first object in BLOCK.  MODEL is the TLS model used
7476    to access it.  */
7477 
7478 rtx
get_section_anchor(struct object_block * block,HOST_WIDE_INT offset,enum tls_model model)7479 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7480 		    enum tls_model model)
7481 {
7482   char label[100];
7483   unsigned int begin, middle, end;
7484   unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7485   rtx anchor;
7486 
7487   /* Work out the anchor's offset.  Use an offset of 0 for the first
7488      anchor so that we don't pessimize the case where we take the address
7489      of a variable at the beginning of the block.  This is particularly
7490      useful when a block has only one variable assigned to it.
7491 
7492      We try to place anchors RANGE bytes apart, so there can then be
7493      anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7494      a ptr_mode offset.  With some target settings, the lowest such
7495      anchor might be out of range for the lowest ptr_mode offset;
7496      likewise the highest anchor for the highest offset.  Use anchors
7497      at the extreme ends of the ptr_mode range in such cases.
7498 
7499      All arithmetic uses unsigned integers in order to avoid
7500      signed overflow.  */
7501   max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7502   min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7503   range = max_offset - min_offset + 1;
7504   if (range == 0)
7505     offset = 0;
7506   else
7507     {
7508       bias = HOST_WIDE_INT_1U << (GET_MODE_BITSIZE (ptr_mode) - 1);
7509       if (offset < 0)
7510 	{
7511 	  delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7512 	  delta -= delta % range;
7513 	  if (delta > bias)
7514 	    delta = bias;
7515 	  offset = (HOST_WIDE_INT) (-delta);
7516 	}
7517       else
7518 	{
7519 	  delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7520 	  delta -= delta % range;
7521 	  if (delta > bias - 1)
7522 	    delta = bias - 1;
7523 	  offset = (HOST_WIDE_INT) delta;
7524 	}
7525     }
7526 
7527   /* Do a binary search to see if there's already an anchor we can use.
7528      Set BEGIN to the new anchor's index if not.  */
7529   begin = 0;
7530   end = vec_safe_length (block->anchors);
7531   while (begin != end)
7532     {
7533       middle = (end + begin) / 2;
7534       anchor = (*block->anchors)[middle];
7535       if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7536 	end = middle;
7537       else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7538 	begin = middle + 1;
7539       else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7540 	end = middle;
7541       else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7542 	begin = middle + 1;
7543       else
7544 	return anchor;
7545     }
7546 
7547   /* Create a new anchor with a unique label.  */
7548   ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7549   anchor = create_block_symbol (ggc_strdup (label), block, offset);
7550   SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7551   SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7552 
7553   /* Insert it at index BEGIN.  */
7554   vec_safe_insert (block->anchors, begin, anchor);
7555   return anchor;
7556 }
7557 
7558 /* Output the objects in BLOCK.  */
7559 
7560 static void
output_object_block(struct object_block * block)7561 output_object_block (struct object_block *block)
7562 {
7563   struct constant_descriptor_rtx *desc;
7564   unsigned int i;
7565   HOST_WIDE_INT offset;
7566   tree decl;
7567   rtx symbol;
7568 
7569   if (!block->objects)
7570     return;
7571 
7572   /* Switch to the section and make sure that the first byte is
7573      suitably aligned.  */
7574   /* Special case VTV comdat sections similar to assemble_variable.  */
7575   if (SECTION_STYLE (block->sect) == SECTION_NAMED
7576       && block->sect->named.name
7577       && (strcmp (block->sect->named.name, ".vtable_map_vars") == 0))
7578     handle_vtv_comdat_section (block->sect, block->sect->named.decl);
7579   else
7580     switch_to_section (block->sect);
7581 
7582   assemble_align (block->alignment);
7583 
7584   /* Define the values of all anchors relative to the current section
7585      position.  */
7586   FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7587     targetm.asm_out.output_anchor (symbol);
7588 
7589   /* Output the objects themselves.  */
7590   offset = 0;
7591   FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7592     {
7593       /* Move to the object's offset, padding with zeros if necessary.  */
7594       assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7595       offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7596       if (CONSTANT_POOL_ADDRESS_P (symbol))
7597 	{
7598 	  desc = SYMBOL_REF_CONSTANT (symbol);
7599 	  /* Pass 1 for align as we have already laid out everything in the block.
7600 	     So aligning shouldn't be necessary.  */
7601 	  output_constant_pool_1 (desc, 1);
7602 	  offset += GET_MODE_SIZE (desc->mode);
7603 	}
7604       else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7605 	{
7606 	  HOST_WIDE_INT size;
7607 	  decl = SYMBOL_REF_DECL (symbol);
7608 	  assemble_constant_contents
7609 	       (DECL_INITIAL (decl), XSTR (symbol, 0), DECL_ALIGN (decl));
7610 
7611 	  size = get_constant_size (DECL_INITIAL (decl));
7612 	  offset += size;
7613 	  if ((flag_sanitize & SANITIZE_ADDRESS)
7614 	      && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7615 	      && asan_protect_global (DECL_INITIAL (decl)))
7616 	    {
7617 	      size = asan_red_zone_size (size);
7618 	      assemble_zeros (size);
7619 	      offset += size;
7620 	    }
7621 	}
7622       else
7623 	{
7624 	  HOST_WIDE_INT size;
7625 	  decl = SYMBOL_REF_DECL (symbol);
7626 	  assemble_variable_contents (decl, XSTR (symbol, 0), false);
7627 	  size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7628 	  offset += size;
7629 	  if ((flag_sanitize & SANITIZE_ADDRESS)
7630 	      && asan_protect_global (decl))
7631 	    {
7632 	      size = asan_red_zone_size (size);
7633 	      assemble_zeros (size);
7634 	      offset += size;
7635 	    }
7636 	}
7637     }
7638 }
7639 
7640 /* A callback for qsort to compare object_blocks.  */
7641 
7642 static int
output_object_block_compare(const void * x,const void * y)7643 output_object_block_compare (const void *x, const void *y)
7644 {
7645   object_block *p1 = *(object_block * const*)x;
7646   object_block *p2 = *(object_block * const*)y;
7647 
7648   if (p1->sect->common.flags & SECTION_NAMED
7649       && !(p2->sect->common.flags & SECTION_NAMED))
7650     return 1;
7651 
7652   if (!(p1->sect->common.flags & SECTION_NAMED)
7653       && p2->sect->common.flags & SECTION_NAMED)
7654     return -1;
7655 
7656   if (p1->sect->common.flags & SECTION_NAMED
7657       && p2->sect->common.flags & SECTION_NAMED)
7658     return strcmp (p1->sect->named.name, p2->sect->named.name);
7659 
7660   unsigned f1 = p1->sect->common.flags;
7661   unsigned f2 = p2->sect->common.flags;
7662   if (f1 == f2)
7663     return 0;
7664   return f1 < f2 ? -1 : 1;
7665 }
7666 
7667 /* Output the definitions of all object_blocks.  */
7668 
7669 void
output_object_blocks(void)7670 output_object_blocks (void)
7671 {
7672   vec<object_block *, va_heap> v;
7673   v.create (object_block_htab->elements ());
7674   object_block *obj;
7675   hash_table<object_block_hasher>::iterator hi;
7676 
7677   FOR_EACH_HASH_TABLE_ELEMENT (*object_block_htab, obj, object_block *, hi)
7678     v.quick_push (obj);
7679 
7680   /* Sort them in order to output them in a deterministic manner,
7681      otherwise we may get .rodata sections in different orders with
7682      and without -g.  */
7683   v.qsort (output_object_block_compare);
7684   unsigned i;
7685   FOR_EACH_VEC_ELT (v, i, obj)
7686     output_object_block (obj);
7687 
7688   v.release ();
7689 }
7690 
7691 /* This function provides a possible implementation of the
7692    TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets.  When triggered
7693    by -frecord-gcc-switches it creates a new mergeable, string section in the
7694    assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7695    contains the switches in ASCII format.
7696 
7697    FIXME: This code does not correctly handle double quote characters
7698    that appear inside strings, (it strips them rather than preserving them).
7699    FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7700    characters - instead it treats them as sub-string separators.  Since
7701    we want to emit NUL strings terminators into the object file we have to use
7702    ASM_OUTPUT_SKIP.  */
7703 
7704 int
elf_record_gcc_switches(print_switch_type type,const char * name)7705 elf_record_gcc_switches (print_switch_type type, const char * name)
7706 {
7707   switch (type)
7708     {
7709     case SWITCH_TYPE_PASSED:
7710       ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7711       ASM_OUTPUT_SKIP (asm_out_file, HOST_WIDE_INT_1U);
7712       break;
7713 
7714     case SWITCH_TYPE_DESCRIPTIVE:
7715       if (name == NULL)
7716 	{
7717 	  /* Distinguish between invocations where name is NULL.  */
7718 	  static bool started = false;
7719 
7720 	  if (!started)
7721 	    {
7722 	      section * sec;
7723 
7724 	      sec = get_section (targetm.asm_out.record_gcc_switches_section,
7725 				 SECTION_DEBUG
7726 				 | SECTION_MERGE
7727 				 | SECTION_STRINGS
7728 				 | (SECTION_ENTSIZE & 1),
7729 				 NULL);
7730 	      switch_to_section (sec);
7731 	      started = true;
7732 	    }
7733 	}
7734 
7735     default:
7736       break;
7737     }
7738 
7739   /* The return value is currently ignored by the caller, but must be 0.
7740      For -fverbose-asm the return value would be the number of characters
7741      emitted into the assembler file.  */
7742   return 0;
7743 }
7744 
7745 /* Emit text to declare externally defined symbols. It is needed to
7746    properly support non-default visibility.  */
7747 void
default_elf_asm_output_external(FILE * file ATTRIBUTE_UNUSED,tree decl,const char * name ATTRIBUTE_UNUSED)7748 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7749 				 tree decl,
7750 				 const char *name ATTRIBUTE_UNUSED)
7751 {
7752   /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7753      set in order to avoid putting out names that are never really
7754      used.  Always output visibility specified in the source.  */
7755   if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7756       && (DECL_VISIBILITY_SPECIFIED (decl)
7757 	  || targetm.binds_local_p (decl)))
7758     maybe_assemble_visibility (decl);
7759 }
7760 
7761 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME.  */
7762 
7763 void
default_asm_output_source_filename(FILE * file,const char * name)7764 default_asm_output_source_filename (FILE *file, const char *name)
7765 {
7766 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7767   ASM_OUTPUT_SOURCE_FILENAME (file, name);
7768 #else
7769   fprintf (file, "\t.file\t");
7770   output_quoted_string (file, name);
7771   putc ('\n', file);
7772 #endif
7773 }
7774 
7775 /* Output a file name in the form wanted by System V.  */
7776 
7777 void
output_file_directive(FILE * asm_file,const char * input_name)7778 output_file_directive (FILE *asm_file, const char *input_name)
7779 {
7780   int len;
7781   const char *na;
7782 
7783   if (input_name == NULL)
7784     input_name = "<stdin>";
7785   else
7786     input_name = remap_debug_filename (input_name);
7787 
7788   len = strlen (input_name);
7789   na = input_name + len;
7790 
7791   /* NA gets INPUT_NAME sans directory names.  */
7792   while (na > input_name)
7793     {
7794       if (IS_DIR_SEPARATOR (na[-1]))
7795 	break;
7796       na--;
7797     }
7798 
7799   targetm.asm_out.output_source_filename (asm_file, na);
7800 }
7801 
7802 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7803    EXP.  */
7804 rtx
make_debug_expr_from_rtl(const_rtx exp)7805 make_debug_expr_from_rtl (const_rtx exp)
7806 {
7807   tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7808   machine_mode mode = GET_MODE (exp);
7809   rtx dval;
7810 
7811   DECL_ARTIFICIAL (ddecl) = 1;
7812   if (REG_P (exp) && REG_EXPR (exp))
7813     type = TREE_TYPE (REG_EXPR (exp));
7814   else if (MEM_P (exp) && MEM_EXPR (exp))
7815     type = TREE_TYPE (MEM_EXPR (exp));
7816   else
7817     type = NULL_TREE;
7818   if (type && TYPE_MODE (type) == mode)
7819     TREE_TYPE (ddecl) = type;
7820   else
7821     TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7822   SET_DECL_MODE (ddecl, mode);
7823   dval = gen_rtx_DEBUG_EXPR (mode);
7824   DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7825   SET_DECL_RTL (ddecl, dval);
7826   return dval;
7827 }
7828 
7829 #ifdef ELF_ASCII_ESCAPES
7830 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets.  */
7831 
7832 void
default_elf_asm_output_limited_string(FILE * f,const char * s)7833 default_elf_asm_output_limited_string (FILE *f, const char *s)
7834 {
7835   int escape;
7836   unsigned char c;
7837 
7838   fputs (STRING_ASM_OP, f);
7839   putc ('"', f);
7840   while (*s != '\0')
7841     {
7842       c = *s;
7843       escape = ELF_ASCII_ESCAPES[c];
7844       switch (escape)
7845 	{
7846 	case 0:
7847 	  putc (c, f);
7848 	  break;
7849 	case 1:
7850 	  putc ('\\', f);
7851 	  putc ('0'+((c>>6)&7), f);
7852 	  putc ('0'+((c>>3)&7), f);
7853 	  putc ('0'+(c&7), f);
7854 	  break;
7855 	default:
7856 	  putc ('\\', f);
7857 	  putc (escape, f);
7858 	  break;
7859 	}
7860       s++;
7861     }
7862   putc ('\"', f);
7863   putc ('\n', f);
7864 }
7865 
7866 /* Default ASM_OUTPUT_ASCII for ELF targets.  */
7867 
7868 void
default_elf_asm_output_ascii(FILE * f,const char * s,unsigned int len)7869 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7870 {
7871   const char *limit = s + len;
7872   const char *last_null = NULL;
7873   unsigned bytes_in_chunk = 0;
7874   unsigned char c;
7875   int escape;
7876 
7877   for (; s < limit; s++)
7878     {
7879       const char *p;
7880 
7881       if (bytes_in_chunk >= 60)
7882 	{
7883 	  putc ('\"', f);
7884 	  putc ('\n', f);
7885 	  bytes_in_chunk = 0;
7886 	}
7887 
7888       if (s > last_null)
7889 	{
7890 	  for (p = s; p < limit && *p != '\0'; p++)
7891 	    continue;
7892 	  last_null = p;
7893 	}
7894       else
7895 	p = last_null;
7896 
7897       if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7898 	{
7899 	  if (bytes_in_chunk > 0)
7900 	    {
7901 	      putc ('\"', f);
7902 	      putc ('\n', f);
7903 	      bytes_in_chunk = 0;
7904 	    }
7905 
7906 	  default_elf_asm_output_limited_string (f, s);
7907 	  s = p;
7908 	}
7909       else
7910 	{
7911 	  if (bytes_in_chunk == 0)
7912 	    fputs (ASCII_DATA_ASM_OP "\"", f);
7913 
7914 	  c = *s;
7915 	  escape = ELF_ASCII_ESCAPES[c];
7916 	  switch (escape)
7917 	    {
7918 	    case 0:
7919 	      putc (c, f);
7920 	      bytes_in_chunk++;
7921 	      break;
7922 	    case 1:
7923 	      putc ('\\', f);
7924 	      putc ('0'+((c>>6)&7), f);
7925 	      putc ('0'+((c>>3)&7), f);
7926 	      putc ('0'+(c&7), f);
7927 	      bytes_in_chunk += 4;
7928 	      break;
7929 	    default:
7930 	      putc ('\\', f);
7931 	      putc (escape, f);
7932 	      bytes_in_chunk += 2;
7933 	      break;
7934 	    }
7935 
7936 	}
7937     }
7938 
7939   if (bytes_in_chunk > 0)
7940     {
7941       putc ('\"', f);
7942       putc ('\n', f);
7943     }
7944 }
7945 #endif
7946 
7947 static GTY(()) section *elf_init_array_section;
7948 static GTY(()) section *elf_fini_array_section;
7949 
7950 static section *
get_elf_initfini_array_priority_section(int priority,bool constructor_p)7951 get_elf_initfini_array_priority_section (int priority,
7952 					 bool constructor_p)
7953 {
7954   section *sec;
7955   if (priority != DEFAULT_INIT_PRIORITY)
7956     {
7957       char buf[18];
7958       sprintf (buf, "%s.%.5u",
7959 	       constructor_p ? ".init_array" : ".fini_array",
7960 	       priority);
7961       sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7962     }
7963   else
7964     {
7965       if (constructor_p)
7966 	{
7967 	  if (elf_init_array_section == NULL)
7968 	    elf_init_array_section
7969 	      = get_section (".init_array",
7970 			     SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7971 	  sec = elf_init_array_section;
7972 	}
7973       else
7974 	{
7975 	  if (elf_fini_array_section == NULL)
7976 	    elf_fini_array_section
7977 	      = get_section (".fini_array",
7978 			     SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7979 	  sec = elf_fini_array_section;
7980 	}
7981     }
7982   return sec;
7983 }
7984 
7985 /* Use .init_array section for constructors. */
7986 
7987 void
default_elf_init_array_asm_out_constructor(rtx symbol,int priority)7988 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7989 {
7990   section *sec = get_elf_initfini_array_priority_section (priority,
7991 							  true);
7992   assemble_addr_to_section (symbol, sec);
7993 }
7994 
7995 /* Use .fini_array section for destructors. */
7996 
7997 void
default_elf_fini_array_asm_out_destructor(rtx symbol,int priority)7998 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7999 {
8000   section *sec = get_elf_initfini_array_priority_section (priority,
8001 							  false);
8002   assemble_addr_to_section (symbol, sec);
8003 }
8004 
8005 /* Default TARGET_ASM_OUTPUT_IDENT hook.
8006 
8007    This is a bit of a cheat.  The real default is a no-op, but this
8008    hook is the default for all targets with a .ident directive.  */
8009 
8010 void
default_asm_output_ident_directive(const char * ident_str)8011 default_asm_output_ident_directive (const char *ident_str)
8012 {
8013   const char *ident_asm_op = "\t.ident\t";
8014 
8015   /* If we are still in the front end, do not write out the string
8016      to asm_out_file.  Instead, add a fake top-level asm statement.
8017      This allows the front ends to use this hook without actually
8018      writing to asm_out_file, to handle #ident or Pragma Ident.  */
8019   if (symtab->state == PARSING)
8020     {
8021       char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
8022       symtab->finalize_toplevel_asm (build_string (strlen (buf), buf));
8023     }
8024   else
8025     fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
8026 }
8027 
8028 
8029 /* This function ensures that vtable_map variables are not only
8030    in the comdat section, but that each variable has its own unique
8031    comdat name.  Without this the variables end up in the same section
8032    with a single comdat name.
8033 
8034    FIXME:  resolve_unique_section needs to deal better with
8035    decls with both DECL_SECTION_NAME and DECL_ONE_ONLY.  Once
8036    that is fixed, this if-else statement can be replaced with
8037    a single call to "switch_to_section (sect)".  */
8038 
8039 static void
handle_vtv_comdat_section(section * sect,const_tree decl ATTRIBUTE_UNUSED)8040 handle_vtv_comdat_section (section *sect, const_tree decl ATTRIBUTE_UNUSED)
8041 {
8042 #if defined (OBJECT_FORMAT_ELF)
8043   targetm.asm_out.named_section (sect->named.name,
8044 				 sect->named.common.flags
8045 				 | SECTION_LINKONCE,
8046 				 DECL_NAME (decl));
8047   in_section = sect;
8048 #else
8049   /* Neither OBJECT_FORMAT_PE, nor OBJECT_FORMAT_COFF is set here.
8050      Therefore the following check is used.
8051      In case a the target is PE or COFF a comdat group section
8052      is created, e.g. .vtable_map_vars$foo. The linker places
8053      everything in .vtable_map_vars at the end.
8054 
8055      A fix could be made in
8056      gcc/config/i386/winnt.c: i386_pe_unique_section.  */
8057   if (TARGET_PECOFF)
8058     {
8059       char *name;
8060 
8061       if (TREE_CODE (DECL_NAME (decl)) == IDENTIFIER_NODE)
8062 	name = ACONCAT ((sect->named.name, "$",
8063 			 IDENTIFIER_POINTER (DECL_NAME (decl)), NULL));
8064       else
8065 	name = ACONCAT ((sect->named.name, "$",
8066 			 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (DECL_NAME (decl))),
8067 			 NULL));
8068 
8069       targetm.asm_out.named_section (name,
8070 				     sect->named.common.flags
8071 				     | SECTION_LINKONCE,
8072 				     DECL_NAME (decl));
8073       in_section = sect;
8074     }
8075   else
8076     switch_to_section (sect);
8077 #endif
8078 }
8079 
8080 #include "gt-varasm.h"
8081