xref: /openbsd/gnu/gcc/gcc/config/darwin.c (revision 404b540a)
1 /* Functions for generic Darwin as target machine for GNU C compiler.
2    Copyright (C) 1989, 1990, 1991, 1992, 1993, 2000, 2001, 2002, 2003, 2004,
3    2005
4    Free Software Foundation, Inc.
5    Contributed by Apple Computer Inc.
6 
7 This file is part of GCC.
8 
9 GCC is free software; you can redistribute it and/or modify
10 it under the terms of the GNU General Public License as published by
11 the Free Software Foundation; either version 2, or (at your option)
12 any later version.
13 
14 GCC is distributed in the hope that it will be useful,
15 but WITHOUT ANY WARRANTY; without even the implied warranty of
16 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
17 GNU General Public License for more details.
18 
19 You should have received a copy of the GNU General Public License
20 along with GCC; see the file COPYING.  If not, write to
21 the Free Software Foundation, 51 Franklin Street, Fifth Floor,
22 Boston, MA 02110-1301, USA.  */
23 
24 #include "config.h"
25 #include "system.h"
26 #include "coretypes.h"
27 #include "tm.h"
28 #include "rtl.h"
29 #include "regs.h"
30 #include "hard-reg-set.h"
31 #include "real.h"
32 #include "insn-config.h"
33 #include "conditions.h"
34 #include "insn-flags.h"
35 #include "output.h"
36 #include "insn-attr.h"
37 #include "flags.h"
38 #include "tree.h"
39 #include "expr.h"
40 #include "reload.h"
41 #include "function.h"
42 #include "ggc.h"
43 #include "langhooks.h"
44 #include "target.h"
45 #include "tm_p.h"
46 #include "toplev.h"
47 #include "hashtab.h"
48 
49 /* Darwin supports a feature called fix-and-continue, which is used
50    for rapid turn around debugging.  When code is compiled with the
51    -mfix-and-continue flag, two changes are made to the generated code
52    that allow the system to do things that it would normally not be
53    able to do easily.  These changes allow gdb to load in
54    recompilation of a translation unit that has been changed into a
55    running program and replace existing functions and methods of that
56    translation unit with versions of those functions and methods
57    from the newly compiled translation unit.  The new functions access
58    the existing static symbols from the old translation unit, if the
59    symbol existed in the unit to be replaced, and from the new
60    translation unit, otherwise.
61 
62    The changes are to insert 5 nops at the beginning of all functions
63    and to use indirection to get at static symbols.  The 5 nops
64    are required by consumers of the generated code.  Currently, gdb
65    uses this to patch in a jump to the overriding function, this
66    allows all uses of the old name to forward to the replacement,
67    including existing function pointers and virtual methods.  See
68    rs6000_emit_prologue for the code that handles the nop insertions.
69 
70    The added indirection allows gdb to redirect accesses to static
71    symbols from the newly loaded translation unit to the existing
72    symbol, if any.  @code{static} symbols are special and are handled by
73    setting the second word in the .non_lazy_symbol_pointer data
74    structure to symbol.  See indirect_data for the code that handles
75    the extra indirection, and machopic_output_indirection and its use
76    of MACHO_SYMBOL_STATIC for the code that handles @code{static}
77    symbol indirection.  */
78 
79 /* Section names.  */
80 section * darwin_sections[NUM_DARWIN_SECTIONS];
81 
82 /* True if we're setting __attribute__ ((ms_struct)).  */
83 int darwin_ms_struct = false;
84 
85 /* A get_unnamed_section callback used to switch to an ObjC section.
86    DIRECTIVE is as for output_section_asm_op.  */
87 
88 static void
output_objc_section_asm_op(const void * directive)89 output_objc_section_asm_op (const void *directive)
90 {
91   static bool been_here = false;
92 
93   if (! been_here)
94     {
95       static const enum darwin_section_enum tomark[] =
96 	{
97 	  /* written, cold -> hot */
98 	  objc_cat_cls_meth_section,
99 	  objc_cat_inst_meth_section,
100 	  objc_string_object_section,
101 	  objc_constant_string_object_section,
102 	  objc_selector_refs_section,
103 	  objc_selector_fixup_section,
104 	  objc_cls_refs_section,
105 	  objc_class_section,
106 	  objc_meta_class_section,
107 	  /* shared, hot -> cold */
108 	  objc_cls_meth_section,
109 	  objc_inst_meth_section,
110 	  objc_protocol_section,
111 	  objc_class_names_section,
112 	  objc_meth_var_types_section,
113 	  objc_meth_var_names_section,
114 	  objc_category_section,
115 	  objc_class_vars_section,
116 	  objc_instance_vars_section,
117 	  objc_module_info_section,
118 	  objc_symbols_section
119 	};
120       size_t i;
121 
122       been_here = true;
123       for (i = 0; i < ARRAY_SIZE (tomark); i++)
124 	switch_to_section (darwin_sections[tomark[i]]);
125     }
126   output_section_asm_op (directive);
127 }
128 
129 /* Implement TARGET_ASM_INIT_SECTIONS.  */
130 
131 void
darwin_init_sections(void)132 darwin_init_sections (void)
133 {
134 #define DEF_SECTION(NAME, FLAGS, DIRECTIVE, OBJC)		\
135   darwin_sections[NAME] =					\
136     get_unnamed_section (FLAGS, (OBJC				\
137 				 ? output_objc_section_asm_op	\
138 				 : output_section_asm_op),	\
139 			 "\t" DIRECTIVE);
140 #include "config/darwin-sections.def"
141 #undef DEF_SECTION
142 
143   readonly_data_section = darwin_sections[const_section];
144   exception_section = darwin_sections[darwin_exception_section];
145   eh_frame_section = darwin_sections[darwin_eh_frame_section];
146 }
147 
148 int
name_needs_quotes(const char * name)149 name_needs_quotes (const char *name)
150 {
151   int c;
152   while ((c = *name++) != '\0')
153     if (! ISIDNUM (c) && c != '.' && c != '$')
154       return 1;
155   return 0;
156 }
157 
158 /* Return true if SYM_REF can be used without an indirection.  */
159 static int
machopic_symbol_defined_p(rtx sym_ref)160 machopic_symbol_defined_p (rtx sym_ref)
161 {
162   if (SYMBOL_REF_FLAGS (sym_ref) & MACHO_SYMBOL_FLAG_DEFINED)
163     return true;
164 
165   /* If a symbol references local and is not an extern to this
166      file, then the symbol might be able to declared as defined.  */
167   if (SYMBOL_REF_LOCAL_P (sym_ref) && ! SYMBOL_REF_EXTERNAL_P (sym_ref))
168     {
169       /* If the symbol references a variable and the variable is a
170 	 common symbol, then this symbol is not defined.  */
171       if (SYMBOL_REF_FLAGS (sym_ref) & MACHO_SYMBOL_FLAG_VARIABLE)
172 	{
173 	  tree decl = SYMBOL_REF_DECL (sym_ref);
174 	  if (!decl)
175 	    return true;
176 	  if (DECL_COMMON (decl))
177 	    return false;
178 	}
179       return true;
180     }
181   return false;
182 }
183 
184 /* This module assumes that (const (symbol_ref "foo")) is a legal pic
185    reference, which will not be changed.  */
186 
187 enum machopic_addr_class
machopic_classify_symbol(rtx sym_ref)188 machopic_classify_symbol (rtx sym_ref)
189 {
190   int flags;
191   bool function_p;
192 
193   flags = SYMBOL_REF_FLAGS (sym_ref);
194   function_p = SYMBOL_REF_FUNCTION_P (sym_ref);
195   if (machopic_symbol_defined_p (sym_ref))
196     return (function_p
197 	    ? MACHOPIC_DEFINED_FUNCTION : MACHOPIC_DEFINED_DATA);
198   else
199     return (function_p
200 	    ? MACHOPIC_UNDEFINED_FUNCTION : MACHOPIC_UNDEFINED_DATA);
201 }
202 
203 #ifndef TARGET_FIX_AND_CONTINUE
204 #define TARGET_FIX_AND_CONTINUE 0
205 #endif
206 
207 /* Indicate when fix-and-continue style code generation is being used
208    and when a reference to data should be indirected so that it can be
209    rebound in a new translation unit to reference the original instance
210    of that data.  Symbol names that are for code generation local to
211    the translation unit are bound to the new translation unit;
212    currently this means symbols that begin with L or _OBJC_;
213    otherwise, we indicate that an indirect reference should be made to
214    permit the runtime to rebind new instances of the translation unit
215    to the original instance of the data.  */
216 
217 static int
indirect_data(rtx sym_ref)218 indirect_data (rtx sym_ref)
219 {
220   int lprefix;
221   const char *name;
222 
223   /* If we aren't generating fix-and-continue code, don't do anything special.  */
224   if (TARGET_FIX_AND_CONTINUE == 0)
225     return 0;
226 
227   /* Otherwise, all symbol except symbols that begin with L or _OBJC_
228      are indirected.  Symbols that begin with L and _OBJC_ are always
229      bound to the current translation unit as they are used for
230      generated local data of the translation unit.  */
231 
232   name = XSTR (sym_ref, 0);
233 
234   lprefix = (((name[0] == '*' || name[0] == '&')
235               && (name[1] == 'L' || (name[1] == '"' && name[2] == 'L')))
236              || (strncmp (name, "_OBJC_", 6) == 0));
237 
238   return ! lprefix;
239 }
240 
241 
242 static int
machopic_data_defined_p(rtx sym_ref)243 machopic_data_defined_p (rtx sym_ref)
244 {
245   if (indirect_data (sym_ref))
246     return 0;
247 
248   switch (machopic_classify_symbol (sym_ref))
249     {
250     case MACHOPIC_DEFINED_DATA:
251     case MACHOPIC_DEFINED_FUNCTION:
252       return 1;
253     default:
254       return 0;
255     }
256 }
257 
258 void
machopic_define_symbol(rtx mem)259 machopic_define_symbol (rtx mem)
260 {
261   rtx sym_ref;
262 
263   gcc_assert (GET_CODE (mem) == MEM);
264   sym_ref = XEXP (mem, 0);
265   SYMBOL_REF_FLAGS (sym_ref) |= MACHO_SYMBOL_FLAG_DEFINED;
266 }
267 
268 static GTY(()) char * function_base;
269 
270 const char *
machopic_function_base_name(void)271 machopic_function_base_name (void)
272 {
273   /* if dynamic-no-pic is on, we should not get here */
274   gcc_assert (!MACHO_DYNAMIC_NO_PIC_P);
275 
276   if (function_base == NULL)
277     function_base =
278       (char *) ggc_alloc_string ("<pic base>", sizeof ("<pic base>"));
279 
280   current_function_uses_pic_offset_table = 1;
281 
282   return function_base;
283 }
284 
285 /* Return a SYMBOL_REF for the PIC function base.  */
286 
287 rtx
machopic_function_base_sym(void)288 machopic_function_base_sym (void)
289 {
290   rtx sym_ref;
291 
292   sym_ref = gen_rtx_SYMBOL_REF (Pmode, machopic_function_base_name ());
293   SYMBOL_REF_FLAGS (sym_ref)
294     |= (MACHO_SYMBOL_FLAG_VARIABLE | MACHO_SYMBOL_FLAG_DEFINED);
295   return sym_ref;
296 }
297 
298 /* Return either ORIG or (const:P (minus:P ORIG PIC_BASE)), depending
299    on whether pic_base is NULL or not.  */
300 static inline rtx
gen_pic_offset(rtx orig,rtx pic_base)301 gen_pic_offset (rtx orig, rtx pic_base)
302 {
303   if (!pic_base)
304     return orig;
305   else
306     return gen_rtx_CONST (Pmode, gen_rtx_MINUS (Pmode, orig, pic_base));
307 }
308 
309 static GTY(()) const char * function_base_func_name;
310 static GTY(()) int current_pic_label_num;
311 
312 void
machopic_output_function_base_name(FILE * file)313 machopic_output_function_base_name (FILE *file)
314 {
315   const char *current_name;
316 
317   /* If dynamic-no-pic is on, we should not get here.  */
318   gcc_assert (!MACHO_DYNAMIC_NO_PIC_P);
319   current_name =
320     IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (current_function_decl));
321   if (function_base_func_name != current_name)
322     {
323       ++current_pic_label_num;
324       function_base_func_name = current_name;
325     }
326   fprintf (file, "\"L%011d$pb\"", current_pic_label_num);
327 }
328 
329 /* The suffix attached to non-lazy pointer symbols.  */
330 #define NON_LAZY_POINTER_SUFFIX "$non_lazy_ptr"
331 /* The suffix attached to stub symbols.  */
332 #define STUB_SUFFIX "$stub"
333 
334 typedef struct machopic_indirection GTY (())
335 {
336   /* The SYMBOL_REF for the entity referenced.  */
337   rtx symbol;
338   /* The name of the stub or non-lazy pointer.  */
339   const char * ptr_name;
340   /* True iff this entry is for a stub (as opposed to a non-lazy
341      pointer).  */
342   bool stub_p;
343   /* True iff this stub or pointer pointer has been referenced.  */
344   bool used;
345 } machopic_indirection;
346 
347 /* A table mapping stub names and non-lazy pointer names to
348    SYMBOL_REFs for the stubbed-to and pointed-to entities.  */
349 
350 static GTY ((param_is (struct machopic_indirection))) htab_t
351   machopic_indirections;
352 
353 /* Return a hash value for a SLOT in the indirections hash table.  */
354 
355 static hashval_t
machopic_indirection_hash(const void * slot)356 machopic_indirection_hash (const void *slot)
357 {
358   const machopic_indirection *p = (const machopic_indirection *) slot;
359   return htab_hash_string (p->ptr_name);
360 }
361 
362 /* Returns true if the KEY is the same as that associated with
363    SLOT.  */
364 
365 static int
machopic_indirection_eq(const void * slot,const void * key)366 machopic_indirection_eq (const void *slot, const void *key)
367 {
368   return strcmp (((const machopic_indirection *) slot)->ptr_name, key) == 0;
369 }
370 
371 /* Return the name of the non-lazy pointer (if STUB_P is false) or
372    stub (if STUB_B is true) corresponding to the given name.  */
373 
374 const char *
machopic_indirection_name(rtx sym_ref,bool stub_p)375 machopic_indirection_name (rtx sym_ref, bool stub_p)
376 {
377   char *buffer;
378   const char *name = XSTR (sym_ref, 0);
379   size_t namelen = strlen (name);
380   machopic_indirection *p;
381   void ** slot;
382   bool saw_star = false;
383   bool needs_quotes;
384   const char *suffix;
385   const char *prefix = user_label_prefix;
386   const char *quote = "";
387   tree id;
388 
389   id = maybe_get_identifier (name);
390   if (id)
391     {
392       tree id_orig = id;
393 
394       while (IDENTIFIER_TRANSPARENT_ALIAS (id))
395 	id = TREE_CHAIN (id);
396       if (id != id_orig)
397 	{
398 	  name = IDENTIFIER_POINTER (id);
399 	  namelen = strlen (name);
400 	}
401     }
402 
403   if (name[0] == '*')
404     {
405       saw_star = true;
406       prefix = "";
407       ++name;
408       --namelen;
409     }
410 
411   needs_quotes = name_needs_quotes (name);
412   if (needs_quotes)
413     {
414       quote = "\"";
415     }
416 
417   if (stub_p)
418     suffix = STUB_SUFFIX;
419   else
420     suffix = NON_LAZY_POINTER_SUFFIX;
421 
422   buffer = alloca (strlen ("&L")
423 		   + strlen (prefix)
424 		   + namelen
425 		   + strlen (suffix)
426 		   + 2 * strlen (quote)
427 		   + 1 /* '\0' */);
428 
429   /* Construct the name of the non-lazy pointer or stub.  */
430   sprintf (buffer, "&%sL%s%s%s%s", quote, prefix, name, suffix, quote);
431 
432   if (!machopic_indirections)
433     machopic_indirections = htab_create_ggc (37,
434 					     machopic_indirection_hash,
435 					     machopic_indirection_eq,
436 					     /*htab_del=*/NULL);
437 
438   slot = htab_find_slot_with_hash (machopic_indirections, buffer,
439 				   htab_hash_string (buffer), INSERT);
440   if (*slot)
441     {
442       p = (machopic_indirection *) *slot;
443     }
444   else
445     {
446       p = (machopic_indirection *) ggc_alloc (sizeof (machopic_indirection));
447       p->symbol = sym_ref;
448       p->ptr_name = xstrdup (buffer);
449       p->stub_p = stub_p;
450       p->used = false;
451       *slot = p;
452     }
453 
454   return p->ptr_name;
455 }
456 
457 /* Return the name of the stub for the mcount function.  */
458 
459 const char*
machopic_mcount_stub_name(void)460 machopic_mcount_stub_name (void)
461 {
462   rtx symbol = gen_rtx_SYMBOL_REF (Pmode, "*mcount");
463   return machopic_indirection_name (symbol, /*stub_p=*/true);
464 }
465 
466 /* If NAME is the name of a stub or a non-lazy pointer , mark the stub
467    or non-lazy pointer as used -- and mark the object to which the
468    pointer/stub refers as used as well, since the pointer/stub will
469    emit a reference to it.  */
470 
471 void
machopic_validate_stub_or_non_lazy_ptr(const char * name)472 machopic_validate_stub_or_non_lazy_ptr (const char *name)
473 {
474   machopic_indirection *p;
475 
476   p = ((machopic_indirection *)
477        (htab_find_with_hash (machopic_indirections, name,
478 			     htab_hash_string (name))));
479   if (p && ! p->used)
480     {
481       const char *real_name;
482       tree id;
483 
484       p->used = true;
485 
486       /* Do what output_addr_const will do when we actually call it.  */
487       if (SYMBOL_REF_DECL (p->symbol))
488 	mark_decl_referenced (SYMBOL_REF_DECL (p->symbol));
489 
490       real_name = targetm.strip_name_encoding (XSTR (p->symbol, 0));
491 
492       id = maybe_get_identifier (real_name);
493       if (id)
494 	mark_referenced (id);
495     }
496 }
497 
498 /* Transform ORIG, which may be any data source, to the corresponding
499    source using indirections.  */
500 
501 rtx
machopic_indirect_data_reference(rtx orig,rtx reg)502 machopic_indirect_data_reference (rtx orig, rtx reg)
503 {
504   rtx ptr_ref = orig;
505 
506   if (! MACHOPIC_INDIRECT)
507     return orig;
508 
509   if (GET_CODE (orig) == SYMBOL_REF)
510     {
511       int defined = machopic_data_defined_p (orig);
512 
513       if (defined && MACHO_DYNAMIC_NO_PIC_P)
514 	{
515 #if defined (TARGET_TOC)
516 	  /* Create a new register for CSE opportunities.  */
517 	  rtx hi_reg = (no_new_pseudos ? reg : gen_reg_rtx (Pmode));
518  	  emit_insn (gen_macho_high (hi_reg, orig));
519  	  emit_insn (gen_macho_low (reg, hi_reg, orig));
520 #else
521 	   /* some other cpu -- writeme!  */
522 	   gcc_unreachable ();
523 #endif
524 	   return reg;
525 	}
526       else if (defined)
527 	{
528 #if defined (TARGET_TOC) || defined (HAVE_lo_sum)
529 	  rtx pic_base = machopic_function_base_sym ();
530 	  rtx offset = gen_pic_offset (orig, pic_base);
531 #endif
532 
533 #if defined (TARGET_TOC) /* i.e., PowerPC */
534 	  rtx hi_sum_reg = (no_new_pseudos ? reg : gen_reg_rtx (Pmode));
535 
536 	  gcc_assert (reg);
537 
538 	  emit_insn (gen_rtx_SET (Pmode, hi_sum_reg,
539 			      gen_rtx_PLUS (Pmode, pic_offset_table_rtx,
540 				       gen_rtx_HIGH (Pmode, offset))));
541 	  emit_insn (gen_rtx_SET (Pmode, reg,
542 				  gen_rtx_LO_SUM (Pmode, hi_sum_reg, offset)));
543 
544 	  orig = reg;
545 #else
546 #if defined (HAVE_lo_sum)
547 	  gcc_assert (reg);
548 
549 	  emit_insn (gen_rtx_SET (VOIDmode, reg,
550 				  gen_rtx_HIGH (Pmode, offset)));
551 	  emit_insn (gen_rtx_SET (VOIDmode, reg,
552 				  gen_rtx_LO_SUM (Pmode, reg, offset)));
553 	  emit_insn (gen_rtx_USE (VOIDmode, pic_offset_table_rtx));
554 
555 	  orig = gen_rtx_PLUS (Pmode, pic_offset_table_rtx, reg);
556 #endif
557 #endif
558 	  return orig;
559 	}
560 
561       ptr_ref = (gen_rtx_SYMBOL_REF
562 		 (Pmode,
563 		  machopic_indirection_name (orig, /*stub_p=*/false)));
564 
565       SYMBOL_REF_DATA (ptr_ref) = SYMBOL_REF_DATA (orig);
566 
567       ptr_ref = gen_const_mem (Pmode, ptr_ref);
568       machopic_define_symbol (ptr_ref);
569 
570       return ptr_ref;
571     }
572   else if (GET_CODE (orig) == CONST)
573     {
574       rtx base, result;
575 
576       /* legitimize both operands of the PLUS */
577       if (GET_CODE (XEXP (orig, 0)) == PLUS)
578 	{
579 	  base = machopic_indirect_data_reference (XEXP (XEXP (orig, 0), 0),
580 						   reg);
581 	  orig = machopic_indirect_data_reference (XEXP (XEXP (orig, 0), 1),
582 						   (base == reg ? 0 : reg));
583 	}
584       else
585 	return orig;
586 
587       if (MACHOPIC_PURE && GET_CODE (orig) == CONST_INT)
588 	result = plus_constant (base, INTVAL (orig));
589       else
590 	result = gen_rtx_PLUS (Pmode, base, orig);
591 
592       if (MACHOPIC_JUST_INDIRECT && GET_CODE (base) == MEM)
593 	{
594 	  if (reg)
595 	    {
596 	      emit_move_insn (reg, result);
597 	      result = reg;
598 	    }
599 	  else
600 	    {
601 	      result = force_reg (GET_MODE (result), result);
602 	    }
603 	}
604 
605       return result;
606 
607     }
608   else if (GET_CODE (orig) == MEM)
609     XEXP (ptr_ref, 0) = machopic_indirect_data_reference (XEXP (orig, 0), reg);
610   /* When the target is i386, this code prevents crashes due to the
611      compiler's ignorance on how to move the PIC base register to
612      other registers.  (The reload phase sometimes introduces such
613      insns.)  */
614   else if (GET_CODE (orig) == PLUS
615 	   && GET_CODE (XEXP (orig, 0)) == REG
616 	   && REGNO (XEXP (orig, 0)) == PIC_OFFSET_TABLE_REGNUM
617 #ifdef I386
618 	   /* Prevent the same register from being erroneously used
619 	      as both the base and index registers.  */
620 	   && GET_CODE (XEXP (orig, 1)) == CONST
621 #endif
622 	   && reg)
623     {
624       emit_move_insn (reg, XEXP (orig, 0));
625       XEXP (ptr_ref, 0) = reg;
626     }
627   return ptr_ref;
628 }
629 
630 /* Transform TARGET (a MEM), which is a function call target, to the
631    corresponding symbol_stub if necessary.  Return a new MEM.  */
632 
633 rtx
machopic_indirect_call_target(rtx target)634 machopic_indirect_call_target (rtx target)
635 {
636   if (GET_CODE (target) != MEM)
637     return target;
638 
639   if (MACHOPIC_INDIRECT
640       && GET_CODE (XEXP (target, 0)) == SYMBOL_REF
641       && !(SYMBOL_REF_FLAGS (XEXP (target, 0))
642 	   & MACHO_SYMBOL_FLAG_DEFINED))
643     {
644       rtx sym_ref = XEXP (target, 0);
645       const char *stub_name = machopic_indirection_name (sym_ref,
646 							 /*stub_p=*/true);
647       enum machine_mode mode = GET_MODE (sym_ref);
648 
649       XEXP (target, 0) = gen_rtx_SYMBOL_REF (mode, stub_name);
650       SYMBOL_REF_DATA (XEXP (target, 0)) = SYMBOL_REF_DATA (sym_ref);
651       MEM_READONLY_P (target) = 1;
652       MEM_NOTRAP_P (target) = 1;
653     }
654 
655   return target;
656 }
657 
658 rtx
machopic_legitimize_pic_address(rtx orig,enum machine_mode mode,rtx reg)659 machopic_legitimize_pic_address (rtx orig, enum machine_mode mode, rtx reg)
660 {
661   rtx pic_ref = orig;
662 
663   if (! MACHOPIC_INDIRECT)
664     return orig;
665 
666   /* First handle a simple SYMBOL_REF or LABEL_REF */
667   if (GET_CODE (orig) == LABEL_REF
668       || (GET_CODE (orig) == SYMBOL_REF
669 	  ))
670     {
671       /* addr(foo) = &func+(foo-func) */
672       rtx pic_base;
673 
674       orig = machopic_indirect_data_reference (orig, reg);
675 
676       if (GET_CODE (orig) == PLUS
677 	  && GET_CODE (XEXP (orig, 0)) == REG)
678 	{
679 	  if (reg == 0)
680 	    return force_reg (mode, orig);
681 
682 	  emit_move_insn (reg, orig);
683 	  return reg;
684 	}
685 
686       /* if dynamic-no-pic we don't have a pic base  */
687       if (MACHO_DYNAMIC_NO_PIC_P)
688 	pic_base = NULL;
689       else
690 	pic_base = machopic_function_base_sym ();
691 
692       if (GET_CODE (orig) == MEM)
693 	{
694 	  if (reg == 0)
695 	    {
696 	      gcc_assert (!reload_in_progress);
697 	      reg = gen_reg_rtx (Pmode);
698 	    }
699 
700 #ifdef HAVE_lo_sum
701 	  if (MACHO_DYNAMIC_NO_PIC_P
702 	      && (GET_CODE (XEXP (orig, 0)) == SYMBOL_REF
703 		  || GET_CODE (XEXP (orig, 0)) == LABEL_REF))
704 	    {
705 #if defined (TARGET_TOC)	/* ppc  */
706 	      rtx temp_reg = (no_new_pseudos) ? reg : gen_reg_rtx (Pmode);
707 	      rtx asym = XEXP (orig, 0);
708 	      rtx mem;
709 
710 	      emit_insn (gen_macho_high (temp_reg, asym));
711 	      mem = gen_const_mem (GET_MODE (orig),
712 				   gen_rtx_LO_SUM (Pmode, temp_reg, asym));
713 	      emit_insn (gen_rtx_SET (VOIDmode, reg, mem));
714 #else
715 	      /* Some other CPU -- WriteMe! but right now there are no other platform that can use dynamic-no-pic  */
716 	      gcc_unreachable ();
717 #endif
718 	      pic_ref = reg;
719 	    }
720 	  else
721 	  if (GET_CODE (XEXP (orig, 0)) == SYMBOL_REF
722 	      || GET_CODE (XEXP (orig, 0)) == LABEL_REF)
723 	    {
724 	      rtx offset = gen_pic_offset (XEXP (orig, 0), pic_base);
725 #if defined (TARGET_TOC) /* i.e., PowerPC */
726 	      /* Generating a new reg may expose opportunities for
727 		 common subexpression elimination.  */
728               rtx hi_sum_reg = no_new_pseudos ? reg : gen_reg_rtx (Pmode);
729 	      rtx mem;
730 	      rtx insn;
731 	      rtx sum;
732 
733 	      sum = gen_rtx_HIGH (Pmode, offset);
734 	      if (! MACHO_DYNAMIC_NO_PIC_P)
735 		sum = gen_rtx_PLUS (Pmode, pic_offset_table_rtx, sum);
736 
737 	      emit_insn (gen_rtx_SET (Pmode, hi_sum_reg, sum));
738 
739 	      mem = gen_const_mem (GET_MODE (orig),
740 				  gen_rtx_LO_SUM (Pmode,
741 						  hi_sum_reg, offset));
742 	      insn = emit_insn (gen_rtx_SET (VOIDmode, reg, mem));
743 	      REG_NOTES (insn) = gen_rtx_EXPR_LIST (REG_EQUAL, pic_ref,
744 						    REG_NOTES (insn));
745 
746 	      pic_ref = reg;
747 #else
748 	      emit_insn (gen_rtx_USE (VOIDmode,
749 				      gen_rtx_REG (Pmode,
750 						   PIC_OFFSET_TABLE_REGNUM)));
751 
752 	      emit_insn (gen_rtx_SET (VOIDmode, reg,
753 				      gen_rtx_HIGH (Pmode,
754 						    gen_rtx_CONST (Pmode,
755 								   offset))));
756 	      emit_insn (gen_rtx_SET (VOIDmode, reg,
757 				  gen_rtx_LO_SUM (Pmode, reg,
758 					   gen_rtx_CONST (Pmode, offset))));
759 	      pic_ref = gen_rtx_PLUS (Pmode,
760 				      pic_offset_table_rtx, reg);
761 #endif
762 	    }
763 	  else
764 #endif  /* HAVE_lo_sum */
765 	    {
766 	      rtx pic = pic_offset_table_rtx;
767 	      if (GET_CODE (pic) != REG)
768 		{
769 		  emit_move_insn (reg, pic);
770 		  pic = reg;
771 		}
772 #if 0
773 	      emit_insn (gen_rtx_USE (VOIDmode,
774 				      gen_rtx_REG (Pmode,
775 						   PIC_OFFSET_TABLE_REGNUM)));
776 #endif
777 
778 	      if (reload_in_progress)
779 		regs_ever_live[REGNO (pic)] = 1;
780 	      pic_ref = gen_rtx_PLUS (Pmode, pic,
781 				      gen_pic_offset (XEXP (orig, 0),
782 						      pic_base));
783 	    }
784 
785 #if !defined (TARGET_TOC)
786 	  emit_move_insn (reg, pic_ref);
787 	  pic_ref = gen_const_mem (GET_MODE (orig), reg);
788 #endif
789 	}
790       else
791 	{
792 
793 #ifdef HAVE_lo_sum
794 	  if (GET_CODE (orig) == SYMBOL_REF
795 	      || GET_CODE (orig) == LABEL_REF)
796 	    {
797 	      rtx offset = gen_pic_offset (orig, pic_base);
798 #if defined (TARGET_TOC) /* i.e., PowerPC */
799               rtx hi_sum_reg;
800 
801 	      if (reg == 0)
802 		{
803 		  gcc_assert (!reload_in_progress);
804 		  reg = gen_reg_rtx (Pmode);
805 		}
806 
807 	      hi_sum_reg = reg;
808 
809 	      emit_insn (gen_rtx_SET (Pmode, hi_sum_reg,
810 				      (MACHO_DYNAMIC_NO_PIC_P)
811 				      ? gen_rtx_HIGH (Pmode, offset)
812 				      : gen_rtx_PLUS (Pmode,
813 						      pic_offset_table_rtx,
814 						      gen_rtx_HIGH (Pmode,
815 								    offset))));
816 	      emit_insn (gen_rtx_SET (VOIDmode, reg,
817 				      gen_rtx_LO_SUM (Pmode,
818 						      hi_sum_reg, offset)));
819 	      pic_ref = reg;
820 #else
821 	      emit_insn (gen_rtx_SET (VOIDmode, reg,
822 				      gen_rtx_HIGH (Pmode, offset)));
823 	      emit_insn (gen_rtx_SET (VOIDmode, reg,
824 				      gen_rtx_LO_SUM (Pmode, reg, offset)));
825 	      pic_ref = gen_rtx_PLUS (Pmode,
826 				      pic_offset_table_rtx, reg);
827 #endif
828 	    }
829 	  else
830 #endif  /*  HAVE_lo_sum  */
831 	    {
832 	      if (REG_P (orig)
833 	          || GET_CODE (orig) == SUBREG)
834 		{
835 		  return orig;
836 		}
837 	      else
838 		{
839 		  rtx pic = pic_offset_table_rtx;
840 		  if (GET_CODE (pic) != REG)
841 		    {
842 		      emit_move_insn (reg, pic);
843 		      pic = reg;
844 		    }
845 #if 0
846 		  emit_insn (gen_rtx_USE (VOIDmode,
847 					  pic_offset_table_rtx));
848 #endif
849 		  if (reload_in_progress)
850 		    regs_ever_live[REGNO (pic)] = 1;
851 		  pic_ref = gen_rtx_PLUS (Pmode,
852 					  pic,
853 					  gen_pic_offset (orig, pic_base));
854 		}
855 	    }
856 	}
857 
858       if (GET_CODE (pic_ref) != REG)
859         {
860           if (reg != 0)
861             {
862               emit_move_insn (reg, pic_ref);
863               return reg;
864             }
865           else
866             {
867               return force_reg (mode, pic_ref);
868             }
869         }
870       else
871         {
872           return pic_ref;
873         }
874     }
875 
876   else if (GET_CODE (orig) == SYMBOL_REF)
877     return orig;
878 
879   else if (GET_CODE (orig) == PLUS
880 	   && (GET_CODE (XEXP (orig, 0)) == MEM
881 	       || GET_CODE (XEXP (orig, 0)) == SYMBOL_REF
882 	       || GET_CODE (XEXP (orig, 0)) == LABEL_REF)
883 	   && XEXP (orig, 0) != pic_offset_table_rtx
884 	   && GET_CODE (XEXP (orig, 1)) != REG)
885 
886     {
887       rtx base;
888       int is_complex = (GET_CODE (XEXP (orig, 0)) == MEM);
889 
890       base = machopic_legitimize_pic_address (XEXP (orig, 0), Pmode, reg);
891       orig = machopic_legitimize_pic_address (XEXP (orig, 1),
892 					      Pmode, (base == reg ? 0 : reg));
893       if (GET_CODE (orig) == CONST_INT)
894 	{
895 	  pic_ref = plus_constant (base, INTVAL (orig));
896 	  is_complex = 1;
897 	}
898       else
899 	pic_ref = gen_rtx_PLUS (Pmode, base, orig);
900 
901       if (reg && is_complex)
902 	{
903 	  emit_move_insn (reg, pic_ref);
904 	  pic_ref = reg;
905 	}
906       /* Likewise, should we set special REG_NOTEs here?  */
907     }
908 
909   else if (GET_CODE (orig) == CONST)
910     {
911       return machopic_legitimize_pic_address (XEXP (orig, 0), Pmode, reg);
912     }
913 
914   else if (GET_CODE (orig) == MEM
915 	   && GET_CODE (XEXP (orig, 0)) == SYMBOL_REF)
916     {
917       rtx addr = machopic_legitimize_pic_address (XEXP (orig, 0), Pmode, reg);
918       addr = replace_equiv_address (orig, addr);
919       emit_move_insn (reg, addr);
920       pic_ref = reg;
921     }
922 
923   return pic_ref;
924 }
925 
926 /* Output the stub or non-lazy pointer in *SLOT, if it has been used.
927    DATA is the FILE* for assembly output.  Called from
928    htab_traverse.  */
929 
930 static int
machopic_output_indirection(void ** slot,void * data)931 machopic_output_indirection (void **slot, void *data)
932 {
933   machopic_indirection *p = *((machopic_indirection **) slot);
934   FILE *asm_out_file = (FILE *) data;
935   rtx symbol;
936   const char *sym_name;
937   const char *ptr_name;
938 
939   if (!p->used)
940     return 1;
941 
942   symbol = p->symbol;
943   sym_name = XSTR (symbol, 0);
944   ptr_name = p->ptr_name;
945 
946   if (p->stub_p)
947     {
948       char *sym;
949       char *stub;
950       tree id;
951 
952       id = maybe_get_identifier (sym_name);
953       if (id)
954 	{
955 	  tree id_orig = id;
956 
957 	  while (IDENTIFIER_TRANSPARENT_ALIAS (id))
958 	    id = TREE_CHAIN (id);
959 	  if (id != id_orig)
960 	    sym_name = IDENTIFIER_POINTER (id);
961 	}
962 
963       sym = alloca (strlen (sym_name) + 2);
964       if (sym_name[0] == '*' || sym_name[0] == '&')
965 	strcpy (sym, sym_name + 1);
966       else if (sym_name[0] == '-' || sym_name[0] == '+')
967 	strcpy (sym, sym_name);
968       else
969 	sprintf (sym, "%s%s", user_label_prefix, sym_name);
970 
971       stub = alloca (strlen (ptr_name) + 2);
972       if (ptr_name[0] == '*' || ptr_name[0] == '&')
973 	strcpy (stub, ptr_name + 1);
974       else
975 	sprintf (stub, "%s%s", user_label_prefix, ptr_name);
976 
977       machopic_output_stub (asm_out_file, sym, stub);
978     }
979   else if (! indirect_data (symbol)
980 	   && (machopic_symbol_defined_p (symbol)
981 	       || SYMBOL_REF_LOCAL_P (symbol)))
982     {
983       switch_to_section (data_section);
984       assemble_align (GET_MODE_ALIGNMENT (Pmode));
985       assemble_label (ptr_name);
986       assemble_integer (gen_rtx_SYMBOL_REF (Pmode, sym_name),
987 			GET_MODE_SIZE (Pmode),
988 			GET_MODE_ALIGNMENT (Pmode), 1);
989     }
990   else
991     {
992       rtx init = const0_rtx;
993 
994       switch_to_section (darwin_sections[machopic_nl_symbol_ptr_section]);
995       assemble_name (asm_out_file, ptr_name);
996       fprintf (asm_out_file, ":\n");
997 
998       fprintf (asm_out_file, "\t.indirect_symbol ");
999       assemble_name (asm_out_file, sym_name);
1000       fprintf (asm_out_file, "\n");
1001 
1002       /* Variables that are marked with MACHO_SYMBOL_STATIC need to
1003 	 have their symbol name instead of 0 in the second entry of
1004 	 the non-lazy symbol pointer data structure when they are
1005 	 defined.  This allows the runtime to rebind newer instances
1006 	 of the translation unit with the original instance of the
1007 	 symbol.  */
1008 
1009       if ((SYMBOL_REF_FLAGS (symbol) & MACHO_SYMBOL_STATIC)
1010 	  && machopic_symbol_defined_p (symbol))
1011 	init = gen_rtx_SYMBOL_REF (Pmode, sym_name);
1012 
1013       assemble_integer (init, GET_MODE_SIZE (Pmode),
1014 			GET_MODE_ALIGNMENT (Pmode), 1);
1015     }
1016 
1017   return 1;
1018 }
1019 
1020 void
machopic_finish(FILE * asm_out_file)1021 machopic_finish (FILE *asm_out_file)
1022 {
1023   if (machopic_indirections)
1024     htab_traverse_noresize (machopic_indirections,
1025 			    machopic_output_indirection,
1026 			    asm_out_file);
1027 }
1028 
1029 int
machopic_operand_p(rtx op)1030 machopic_operand_p (rtx op)
1031 {
1032   if (MACHOPIC_JUST_INDIRECT)
1033     {
1034       while (GET_CODE (op) == CONST)
1035 	op = XEXP (op, 0);
1036 
1037       if (GET_CODE (op) == SYMBOL_REF)
1038 	return machopic_symbol_defined_p (op);
1039       else
1040 	return 0;
1041     }
1042 
1043   while (GET_CODE (op) == CONST)
1044     op = XEXP (op, 0);
1045 
1046   if (GET_CODE (op) == MINUS
1047       && GET_CODE (XEXP (op, 0)) == SYMBOL_REF
1048       && GET_CODE (XEXP (op, 1)) == SYMBOL_REF
1049       && machopic_symbol_defined_p (XEXP (op, 0))
1050       && machopic_symbol_defined_p (XEXP (op, 1)))
1051       return 1;
1052 
1053   return 0;
1054 }
1055 
1056 /* This function records whether a given name corresponds to a defined
1057    or undefined function or variable, for machopic_classify_ident to
1058    use later.  */
1059 
1060 void
darwin_encode_section_info(tree decl,rtx rtl,int first ATTRIBUTE_UNUSED)1061 darwin_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
1062 {
1063   rtx sym_ref;
1064 
1065   /* Do the standard encoding things first.  */
1066   default_encode_section_info (decl, rtl, first);
1067 
1068   if (TREE_CODE (decl) != FUNCTION_DECL && TREE_CODE (decl) != VAR_DECL)
1069     return;
1070 
1071   sym_ref = XEXP (rtl, 0);
1072   if (TREE_CODE (decl) == VAR_DECL)
1073     SYMBOL_REF_FLAGS (sym_ref) |= MACHO_SYMBOL_FLAG_VARIABLE;
1074 
1075   if (!DECL_EXTERNAL (decl)
1076       && (!TREE_PUBLIC (decl) || !DECL_WEAK (decl))
1077       && ! lookup_attribute ("weakref", DECL_ATTRIBUTES (decl))
1078       && ((TREE_STATIC (decl)
1079 	   && (!DECL_COMMON (decl) || !TREE_PUBLIC (decl)))
1080 	  || (!DECL_COMMON (decl) && DECL_INITIAL (decl)
1081 	      && DECL_INITIAL (decl) != error_mark_node)))
1082     SYMBOL_REF_FLAGS (sym_ref) |= MACHO_SYMBOL_FLAG_DEFINED;
1083 
1084   if (! TREE_PUBLIC (decl))
1085     SYMBOL_REF_FLAGS (sym_ref) |= MACHO_SYMBOL_STATIC;
1086 }
1087 
1088 void
darwin_mark_decl_preserved(const char * name)1089 darwin_mark_decl_preserved (const char *name)
1090 {
1091   fprintf (asm_out_file, ".no_dead_strip ");
1092   assemble_name (asm_out_file, name);
1093   fputc ('\n', asm_out_file);
1094 }
1095 
1096 int
machopic_reloc_rw_mask(void)1097 machopic_reloc_rw_mask (void)
1098 {
1099   return MACHOPIC_INDIRECT ? 3 : 0;
1100 }
1101 
1102 section *
machopic_select_section(tree exp,int reloc,unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)1103 machopic_select_section (tree exp, int reloc,
1104 			 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
1105 {
1106   section *base_section;
1107   bool weak_p = (DECL_P (exp) && DECL_WEAK (exp)
1108 		 && (lookup_attribute ("weak", DECL_ATTRIBUTES (exp))
1109 		     || ! lookup_attribute ("weak_import",
1110 					    DECL_ATTRIBUTES (exp))));
1111 
1112   if (TREE_CODE (exp) == FUNCTION_DECL)
1113     {
1114       if (reloc == 1)
1115 	base_section = (weak_p
1116 			? darwin_sections[text_unlikely_coal_section]
1117 			: unlikely_text_section ());
1118       else
1119 	base_section = weak_p ? darwin_sections[text_coal_section] : text_section;
1120     }
1121   else if (decl_readonly_section (exp, reloc))
1122     base_section = weak_p ? darwin_sections[const_coal_section] : darwin_sections[const_section];
1123   else if (TREE_READONLY (exp) || TREE_CONSTANT (exp))
1124     base_section = weak_p ? darwin_sections[const_data_coal_section] : darwin_sections[const_data_section];
1125   else
1126     base_section = weak_p ? darwin_sections[data_coal_section] : data_section;
1127 
1128   if (TREE_CODE (exp) == STRING_CST
1129       && ((size_t) TREE_STRING_LENGTH (exp)
1130 	  == strlen (TREE_STRING_POINTER (exp)) + 1))
1131     return darwin_sections[cstring_section];
1132   else if ((TREE_CODE (exp) == INTEGER_CST || TREE_CODE (exp) == REAL_CST)
1133 	   && flag_merge_constants)
1134     {
1135       tree size = TYPE_SIZE_UNIT (TREE_TYPE (exp));
1136 
1137       if (TREE_CODE (size) == INTEGER_CST &&
1138 	  TREE_INT_CST_LOW (size) == 4 &&
1139 	  TREE_INT_CST_HIGH (size) == 0)
1140 	return darwin_sections[literal4_section];
1141       else if (TREE_CODE (size) == INTEGER_CST &&
1142 	       TREE_INT_CST_LOW (size) == 8 &&
1143 	       TREE_INT_CST_HIGH (size) == 0)
1144 	return darwin_sections[literal8_section];
1145       else if (TARGET_64BIT
1146 	       && TREE_CODE (size) == INTEGER_CST
1147 	       && TREE_INT_CST_LOW (size) == 16
1148 	       && TREE_INT_CST_HIGH (size) == 0)
1149 	return darwin_sections[literal16_section];
1150       else
1151 	return base_section;
1152     }
1153   else if (TREE_CODE (exp) == CONSTRUCTOR
1154 	   && TREE_TYPE (exp)
1155 	   && TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE
1156 	   && TYPE_NAME (TREE_TYPE (exp)))
1157     {
1158       tree name = TYPE_NAME (TREE_TYPE (exp));
1159       if (TREE_CODE (name) == TYPE_DECL)
1160 	name = DECL_NAME (name);
1161 
1162       if (!strcmp (IDENTIFIER_POINTER (name), "__builtin_ObjCString"))
1163 	{
1164 	  if (flag_next_runtime)
1165 	    return darwin_sections[objc_constant_string_object_section];
1166 	  else
1167 	    return darwin_sections[objc_string_object_section];
1168 	}
1169       else
1170 	return base_section;
1171     }
1172   else if (TREE_CODE (exp) == VAR_DECL &&
1173 	   DECL_NAME (exp) &&
1174 	   TREE_CODE (DECL_NAME (exp)) == IDENTIFIER_NODE &&
1175 	   IDENTIFIER_POINTER (DECL_NAME (exp)) &&
1176 	   !strncmp (IDENTIFIER_POINTER (DECL_NAME (exp)), "_OBJC_", 6))
1177     {
1178       const char *name = IDENTIFIER_POINTER (DECL_NAME (exp));
1179 
1180       if (!strncmp (name, "_OBJC_CLASS_METHODS_", 20))
1181 	return darwin_sections[objc_cls_meth_section];
1182       else if (!strncmp (name, "_OBJC_INSTANCE_METHODS_", 23))
1183 	return darwin_sections[objc_inst_meth_section];
1184       else if (!strncmp (name, "_OBJC_CATEGORY_CLASS_METHODS_", 20))
1185 	return darwin_sections[objc_cat_cls_meth_section];
1186       else if (!strncmp (name, "_OBJC_CATEGORY_INSTANCE_METHODS_", 23))
1187 	return darwin_sections[objc_cat_inst_meth_section];
1188       else if (!strncmp (name, "_OBJC_CLASS_VARIABLES_", 22))
1189 	return darwin_sections[objc_class_vars_section];
1190       else if (!strncmp (name, "_OBJC_INSTANCE_VARIABLES_", 25))
1191 	return darwin_sections[objc_instance_vars_section];
1192       else if (!strncmp (name, "_OBJC_CLASS_PROTOCOLS_", 22))
1193 	return darwin_sections[objc_cat_cls_meth_section];
1194       else if (!strncmp (name, "_OBJC_CLASS_NAME_", 17))
1195 	return darwin_sections[objc_class_names_section];
1196       else if (!strncmp (name, "_OBJC_METH_VAR_NAME_", 20))
1197 	return darwin_sections[objc_meth_var_names_section];
1198       else if (!strncmp (name, "_OBJC_METH_VAR_TYPE_", 20))
1199 	return darwin_sections[objc_meth_var_types_section];
1200       else if (!strncmp (name, "_OBJC_CLASS_REFERENCES", 22))
1201 	return darwin_sections[objc_cls_refs_section];
1202       else if (!strncmp (name, "_OBJC_CLASS_", 12))
1203 	return darwin_sections[objc_class_section];
1204       else if (!strncmp (name, "_OBJC_METACLASS_", 16))
1205 	return darwin_sections[objc_meta_class_section];
1206       else if (!strncmp (name, "_OBJC_CATEGORY_", 15))
1207 	return darwin_sections[objc_category_section];
1208       else if (!strncmp (name, "_OBJC_SELECTOR_REFERENCES", 25))
1209 	return darwin_sections[objc_selector_refs_section];
1210       else if (!strncmp (name, "_OBJC_SELECTOR_FIXUP", 20))
1211 	return darwin_sections[objc_selector_fixup_section];
1212       else if (!strncmp (name, "_OBJC_SYMBOLS", 13))
1213 	return darwin_sections[objc_symbols_section];
1214       else if (!strncmp (name, "_OBJC_MODULES", 13))
1215 	return darwin_sections[objc_module_info_section];
1216       else if (!strncmp (name, "_OBJC_IMAGE_INFO", 16))
1217 	return darwin_sections[objc_image_info_section];
1218       else if (!strncmp (name, "_OBJC_PROTOCOL_INSTANCE_METHODS_", 32))
1219 	return darwin_sections[objc_cat_inst_meth_section];
1220       else if (!strncmp (name, "_OBJC_PROTOCOL_CLASS_METHODS_", 29))
1221 	return darwin_sections[objc_cat_cls_meth_section];
1222       else if (!strncmp (name, "_OBJC_PROTOCOL_REFS_", 20))
1223 	return darwin_sections[objc_cat_cls_meth_section];
1224       else if (!strncmp (name, "_OBJC_PROTOCOL_", 15))
1225 	return darwin_sections[objc_protocol_section];
1226       else
1227 	return base_section;
1228     }
1229   else
1230     return base_section;
1231 }
1232 
1233 /* This can be called with address expressions as "rtx".
1234    They must go in "const".  */
1235 
1236 section *
machopic_select_rtx_section(enum machine_mode mode,rtx x,unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)1237 machopic_select_rtx_section (enum machine_mode mode, rtx x,
1238 			     unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
1239 {
1240   if (GET_MODE_SIZE (mode) == 8
1241       && (GET_CODE (x) == CONST_INT
1242 	  || GET_CODE (x) == CONST_DOUBLE))
1243     return darwin_sections[literal8_section];
1244   else if (GET_MODE_SIZE (mode) == 4
1245 	   && (GET_CODE (x) == CONST_INT
1246 	       || GET_CODE (x) == CONST_DOUBLE))
1247     return darwin_sections[literal4_section];
1248   else if (TARGET_64BIT
1249 	   && GET_MODE_SIZE (mode) == 16
1250 	   && (GET_CODE (x) == CONST_INT
1251 	       || GET_CODE (x) == CONST_DOUBLE
1252 	       || GET_CODE (x) == CONST_VECTOR))
1253     return darwin_sections[literal16_section];
1254   else if (MACHOPIC_INDIRECT
1255 	   && (GET_CODE (x) == SYMBOL_REF
1256 	       || GET_CODE (x) == CONST
1257 	       || GET_CODE (x) == LABEL_REF))
1258     return darwin_sections[const_data_section];
1259   else
1260     return darwin_sections[const_section];
1261 }
1262 
1263 void
machopic_asm_out_constructor(rtx symbol,int priority ATTRIBUTE_UNUSED)1264 machopic_asm_out_constructor (rtx symbol, int priority ATTRIBUTE_UNUSED)
1265 {
1266   if (MACHOPIC_INDIRECT)
1267     switch_to_section (darwin_sections[mod_init_section]);
1268   else
1269     switch_to_section (darwin_sections[constructor_section]);
1270   assemble_align (POINTER_SIZE);
1271   assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1272 
1273   if (! MACHOPIC_INDIRECT)
1274     fprintf (asm_out_file, ".reference .constructors_used\n");
1275 }
1276 
1277 void
machopic_asm_out_destructor(rtx symbol,int priority ATTRIBUTE_UNUSED)1278 machopic_asm_out_destructor (rtx symbol, int priority ATTRIBUTE_UNUSED)
1279 {
1280   if (MACHOPIC_INDIRECT)
1281     switch_to_section (darwin_sections[mod_term_section]);
1282   else
1283     switch_to_section (darwin_sections[destructor_section]);
1284   assemble_align (POINTER_SIZE);
1285   assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1286 
1287   if (! MACHOPIC_INDIRECT)
1288     fprintf (asm_out_file, ".reference .destructors_used\n");
1289 }
1290 
1291 void
darwin_globalize_label(FILE * stream,const char * name)1292 darwin_globalize_label (FILE *stream, const char *name)
1293 {
1294   if (!!strncmp (name, "_OBJC_", 6))
1295     default_globalize_label (stream, name);
1296 }
1297 
1298 void
darwin_asm_named_section(const char * name,unsigned int flags ATTRIBUTE_UNUSED,tree decl ATTRIBUTE_UNUSED)1299 darwin_asm_named_section (const char *name,
1300 			  unsigned int flags ATTRIBUTE_UNUSED,
1301 			  tree decl ATTRIBUTE_UNUSED)
1302 {
1303   fprintf (asm_out_file, "\t.section %s\n", name);
1304 }
1305 
1306 void
darwin_unique_section(tree decl ATTRIBUTE_UNUSED,int reloc ATTRIBUTE_UNUSED)1307 darwin_unique_section (tree decl ATTRIBUTE_UNUSED, int reloc ATTRIBUTE_UNUSED)
1308 {
1309   /* Darwin does not use unique sections.  */
1310 }
1311 
1312 /* Handle __attribute__ ((apple_kext_compatibility)).
1313    This only applies to darwin kexts for 2.95 compatibility -- it shrinks the
1314    vtable for classes with this attribute (and their descendants) by not
1315    outputting the new 3.0 nondeleting destructor.  This means that such
1316    objects CANNOT be allocated on the stack or as globals UNLESS they have
1317    a completely empty `operator delete'.
1318    Luckily, this fits in with the Darwin kext model.
1319 
1320    This attribute also disables gcc3's potential overlaying of derived
1321    class data members on the padding at the end of the base class.  */
1322 
1323 tree
darwin_handle_kext_attribute(tree * node,tree name,tree args ATTRIBUTE_UNUSED,int flags ATTRIBUTE_UNUSED,bool * no_add_attrs)1324 darwin_handle_kext_attribute (tree *node, tree name,
1325 			      tree args ATTRIBUTE_UNUSED,
1326 			      int flags ATTRIBUTE_UNUSED,
1327 			      bool *no_add_attrs)
1328 {
1329   /* APPLE KEXT stuff -- only applies with pure static C++ code.  */
1330   if (! TARGET_KEXTABI)
1331     {
1332       warning (0, "%<%s%> 2.95 vtable-compatability attribute applies "
1333 	       "only when compiling a kext", IDENTIFIER_POINTER (name));
1334 
1335       *no_add_attrs = true;
1336     }
1337   else if (TREE_CODE (*node) != RECORD_TYPE)
1338     {
1339       warning (0, "%<%s%> 2.95 vtable-compatability attribute applies "
1340 	       "only to C++ classes", IDENTIFIER_POINTER (name));
1341 
1342       *no_add_attrs = true;
1343     }
1344 
1345   return NULL_TREE;
1346 }
1347 
1348 /* Handle a "weak_import" attribute; arguments as in
1349    struct attribute_spec.handler.  */
1350 
1351 tree
darwin_handle_weak_import_attribute(tree * node,tree name,tree ARG_UNUSED (args),int ARG_UNUSED (flags),bool * no_add_attrs)1352 darwin_handle_weak_import_attribute (tree *node, tree name,
1353 				     tree ARG_UNUSED (args),
1354 				     int ARG_UNUSED (flags),
1355 				     bool * no_add_attrs)
1356 {
1357   if (TREE_CODE (*node) != FUNCTION_DECL && TREE_CODE (*node) != VAR_DECL)
1358     {
1359       warning (OPT_Wattributes, "%qs attribute ignored",
1360 	       IDENTIFIER_POINTER (name));
1361       *no_add_attrs = true;
1362     }
1363   else
1364     declare_weak (*node);
1365 
1366   return NULL_TREE;
1367 }
1368 
1369 static void
no_dead_strip(FILE * file,const char * lab)1370 no_dead_strip (FILE *file, const char *lab)
1371 {
1372   fprintf (file, ".no_dead_strip %s\n", lab);
1373 }
1374 
1375 /* Emit a label for an FDE, making it global and/or weak if appropriate.
1376    The third parameter is nonzero if this is for exception handling.
1377    The fourth parameter is nonzero if this is just a placeholder for an
1378    FDE that we are omitting. */
1379 
1380 void
darwin_emit_unwind_label(FILE * file,tree decl,int for_eh,int empty)1381 darwin_emit_unwind_label (FILE *file, tree decl, int for_eh, int empty)
1382 {
1383   const char *base;
1384   char *lab;
1385   bool need_quotes;
1386 
1387   if (DECL_ASSEMBLER_NAME_SET_P (decl))
1388     base = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
1389   else
1390     base = IDENTIFIER_POINTER (DECL_NAME (decl));
1391 
1392   base = targetm.strip_name_encoding (base);
1393   need_quotes = name_needs_quotes (base);
1394 
1395   if (! for_eh)
1396     return;
1397 
1398   lab = concat (need_quotes ? "\"" : "", user_label_prefix, base, ".eh",
1399 		need_quotes ? "\"" : "", NULL);
1400 
1401   if (TREE_PUBLIC (decl))
1402     fprintf (file, "\t%s %s\n",
1403 	     (DECL_VISIBILITY (decl) != VISIBILITY_HIDDEN
1404 	      ? ".globl"
1405 	      : ".private_extern"),
1406 	     lab);
1407 
1408   if (DECL_WEAK (decl))
1409     fprintf (file, "\t.weak_definition %s\n", lab);
1410 
1411   if (empty)
1412     {
1413       fprintf (file, "%s = 0\n", lab);
1414 
1415       /* Mark the absolute .eh and .eh1 style labels as needed to
1416 	 ensure that we don't dead code strip them and keep such
1417 	 labels from another instantiation point until we can fix this
1418 	 properly with group comdat support.  */
1419       no_dead_strip (file, lab);
1420     }
1421   else
1422     fprintf (file, "%s:\n", lab);
1423 
1424   free (lab);
1425 }
1426 
1427 static GTY(()) unsigned long except_table_label_num;
1428 
1429 void
darwin_emit_except_table_label(FILE * file)1430 darwin_emit_except_table_label (FILE *file)
1431 {
1432   char section_start_label[30];
1433 
1434   ASM_GENERATE_INTERNAL_LABEL (section_start_label, "GCC_except_table",
1435 			       except_table_label_num++);
1436   ASM_OUTPUT_LABEL (file, section_start_label);
1437 }
1438 /* Generate a PC-relative reference to a Mach-O non-lazy-symbol.  */
1439 
1440 void
darwin_non_lazy_pcrel(FILE * file,rtx addr)1441 darwin_non_lazy_pcrel (FILE *file, rtx addr)
1442 {
1443   const char *nlp_name;
1444 
1445   gcc_assert (GET_CODE (addr) == SYMBOL_REF);
1446 
1447   nlp_name = machopic_indirection_name (addr, /*stub_p=*/false);
1448   fputs ("\t.long\t", file);
1449   ASM_OUTPUT_LABELREF (file, nlp_name);
1450   fputs ("-.", file);
1451 }
1452 
1453 /* Emit an assembler directive to set visibility for a symbol.  The
1454    only supported visibilities are VISIBILITY_DEFAULT and
1455    VISIBILITY_HIDDEN; the latter corresponds to Darwin's "private
1456    extern".  There is no MACH-O equivalent of ELF's
1457    VISIBILITY_INTERNAL or VISIBILITY_PROTECTED. */
1458 
1459 void
darwin_assemble_visibility(tree decl,int vis)1460 darwin_assemble_visibility (tree decl, int vis)
1461 {
1462   if (vis == VISIBILITY_DEFAULT)
1463     ;
1464   else if (vis == VISIBILITY_HIDDEN)
1465     {
1466       fputs ("\t.private_extern ", asm_out_file);
1467       assemble_name (asm_out_file,
1468 		     (IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl))));
1469       fputs ("\n", asm_out_file);
1470     }
1471   else
1472     warning (OPT_Wattributes, "internal and protected visibility attributes "
1473 	     "not supported in this configuration; ignored");
1474 }
1475 
1476 /* Output a difference of two labels that will be an assembly time
1477    constant if the two labels are local.  (.long lab1-lab2 will be
1478    very different if lab1 is at the boundary between two sections; it
1479    will be relocated according to the second section, not the first,
1480    so one ends up with a difference between labels in different
1481    sections, which is bad in the dwarf2 eh context for instance.)  */
1482 
1483 static int darwin_dwarf_label_counter;
1484 
1485 void
darwin_asm_output_dwarf_delta(FILE * file,int size,const char * lab1,const char * lab2)1486 darwin_asm_output_dwarf_delta (FILE *file, int size,
1487 			       const char *lab1, const char *lab2)
1488 {
1489   int islocaldiff = (lab1[0] == '*' && lab1[1] == 'L'
1490 		     && lab2[0] == '*' && lab2[1] == 'L');
1491   const char *directive = (size == 8 ? ".quad" : ".long");
1492 
1493   if (islocaldiff)
1494     fprintf (file, "\t.set L$set$%d,", darwin_dwarf_label_counter);
1495   else
1496     fprintf (file, "\t%s\t", directive);
1497   assemble_name_raw (file, lab1);
1498   fprintf (file, "-");
1499   assemble_name_raw (file, lab2);
1500   if (islocaldiff)
1501     fprintf (file, "\n\t%s L$set$%d", directive, darwin_dwarf_label_counter++);
1502 }
1503 
1504 /* Output labels for the start of the DWARF sections if necessary.  */
1505 void
darwin_file_start(void)1506 darwin_file_start (void)
1507 {
1508   if (write_symbols == DWARF2_DEBUG)
1509     {
1510       static const char * const debugnames[] =
1511 	{
1512 	  DEBUG_FRAME_SECTION,
1513 	  DEBUG_INFO_SECTION,
1514 	  DEBUG_ABBREV_SECTION,
1515 	  DEBUG_ARANGES_SECTION,
1516 	  DEBUG_MACINFO_SECTION,
1517 	  DEBUG_LINE_SECTION,
1518 	  DEBUG_LOC_SECTION,
1519 	  DEBUG_PUBNAMES_SECTION,
1520 	  DEBUG_STR_SECTION,
1521 	  DEBUG_RANGES_SECTION
1522 	};
1523       size_t i;
1524 
1525       for (i = 0; i < ARRAY_SIZE (debugnames); i++)
1526 	{
1527 	  int namelen;
1528 
1529 	  switch_to_section (get_section (debugnames[i], SECTION_DEBUG, NULL));
1530 
1531 	  gcc_assert (strncmp (debugnames[i], "__DWARF,", 8) == 0);
1532 	  gcc_assert (strchr (debugnames[i] + 8, ','));
1533 
1534 	  namelen = strchr (debugnames[i] + 8, ',') - (debugnames[i] + 8);
1535 	  fprintf (asm_out_file, "Lsection%.*s:\n", namelen, debugnames[i] + 8);
1536 	}
1537     }
1538 }
1539 
1540 /* Output an offset in a DWARF section on Darwin.  On Darwin, DWARF section
1541    offsets are not represented using relocs in .o files; either the
1542    section never leaves the .o file, or the linker or other tool is
1543    responsible for parsing the DWARF and updating the offsets.  */
1544 
1545 void
darwin_asm_output_dwarf_offset(FILE * file,int size,const char * lab,section * base)1546 darwin_asm_output_dwarf_offset (FILE *file, int size, const char * lab,
1547 				section *base)
1548 {
1549   char sname[64];
1550   int namelen;
1551 
1552   gcc_assert (base->common.flags & SECTION_NAMED);
1553   gcc_assert (strncmp (base->named.name, "__DWARF,", 8) == 0);
1554   gcc_assert (strchr (base->named.name + 8, ','));
1555 
1556   namelen = strchr (base->named.name + 8, ',') - (base->named.name + 8);
1557   sprintf (sname, "*Lsection%.*s", namelen, base->named.name + 8);
1558   darwin_asm_output_dwarf_delta (file, size, lab, sname);
1559 }
1560 
1561 void
darwin_file_end(void)1562 darwin_file_end (void)
1563 {
1564   machopic_finish (asm_out_file);
1565   if (strcmp (lang_hooks.name, "GNU C++") == 0)
1566     {
1567       switch_to_section (darwin_sections[constructor_section]);
1568       switch_to_section (darwin_sections[destructor_section]);
1569       ASM_OUTPUT_ALIGN (asm_out_file, 1);
1570     }
1571   fprintf (asm_out_file, "\t.subsections_via_symbols\n");
1572 }
1573 
1574 /* TODO: Add a language hook for identifying if a decl is a vtable.  */
1575 #define DARWIN_VTABLE_P(DECL) 0
1576 
1577 /* Cross-module name binding.  Darwin does not support overriding
1578    functions at dynamic-link time, except for vtables in kexts.  */
1579 
1580 bool
darwin_binds_local_p(tree decl)1581 darwin_binds_local_p (tree decl)
1582 {
1583   return default_binds_local_p_1 (decl,
1584 				  TARGET_KEXTABI && DARWIN_VTABLE_P (decl));
1585 }
1586 
1587 #if 0
1588 /* See TARGET_ASM_OUTPUT_ANCHOR for why we can't do this yet.  */
1589 /* The Darwin's implementation of TARGET_ASM_OUTPUT_ANCHOR.  Define the
1590    anchor relative to ".", the current section position.  We cannot use
1591    the default one because ASM_OUTPUT_DEF is wrong for Darwin.  */
1592 
1593 void
1594 darwin_asm_output_anchor (rtx symbol)
1595 {
1596   fprintf (asm_out_file, "\t.set\t");
1597   assemble_name (asm_out_file, XSTR (symbol, 0));
1598   fprintf (asm_out_file, ", . + " HOST_WIDE_INT_PRINT_DEC "\n",
1599 	   SYMBOL_REF_BLOCK_OFFSET (symbol));
1600 }
1601 #endif
1602 
1603 /* Set the darwin specific attributes on TYPE.  */
1604 void
darwin_set_default_type_attributes(tree type)1605 darwin_set_default_type_attributes (tree type)
1606 {
1607   if (darwin_ms_struct
1608       && TREE_CODE (type) == RECORD_TYPE)
1609     TYPE_ATTRIBUTES (type) = tree_cons (get_identifier ("ms_struct"),
1610                                         NULL_TREE,
1611                                         TYPE_ATTRIBUTES (type));
1612 }
1613 
1614 /* True, iff we're generating code for loadable kernel extentions.  */
1615 
1616 bool
darwin_kextabi_p(void)1617 darwin_kextabi_p (void) {
1618   return flag_apple_kext;
1619 }
1620 
1621 void
darwin_override_options(void)1622 darwin_override_options (void)
1623 {
1624   if (flag_apple_kext && strcmp (lang_hooks.name, "GNU C++") != 0)
1625     {
1626       warning (0, "command line option %<-fapple-kext%> is only valid for C++");
1627       flag_apple_kext = 0;
1628     }
1629   if (flag_mkernel || flag_apple_kext)
1630     {
1631       /* -mkernel implies -fapple-kext for C++ */
1632       if (strcmp (lang_hooks.name, "GNU C++") == 0)
1633 	flag_apple_kext = 1;
1634 
1635       flag_no_common = 1;
1636 
1637       /* No EH in kexts.  */
1638       flag_exceptions = 0;
1639       /* No -fnon-call-exceptions data in kexts.  */
1640       flag_non_call_exceptions = 0;
1641     }
1642 }
1643 
1644 #include "gt-darwin.h"
1645