alias.c (true_dependence): Remove 'abort' from comments.
[gcc.git] / gcc / varasm.c
1 /* Output variables, constants and external declarations, for GNU compiler.
2 Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005
4 Free Software Foundation, Inc.
5
6 This file is part of GCC.
7
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 2, or (at your option) any later
11 version.
12
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 for more details.
17
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING. If not, write to the Free
20 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
21 02111-1307, USA. */
22
23
24 /* This file handles generation of all the assembler code
25 *except* the instructions of a function.
26 This includes declarations of variables and their initial values.
27
28 We also output the assembler code for constants stored in memory
29 and are responsible for combining constants with the same value. */
30
31 #include "config.h"
32 #include "system.h"
33 #include "coretypes.h"
34 #include "tm.h"
35 #include "rtl.h"
36 #include "tree.h"
37 #include "flags.h"
38 #include "function.h"
39 #include "expr.h"
40 #include "hard-reg-set.h"
41 #include "regs.h"
42 #include "real.h"
43 #include "output.h"
44 #include "toplev.h"
45 #include "hashtab.h"
46 #include "c-pragma.h"
47 #include "ggc.h"
48 #include "langhooks.h"
49 #include "tm_p.h"
50 #include "debug.h"
51 #include "target.h"
52 #include "tree-mudflap.h"
53 #include "cgraph.h"
54 #include "cfglayout.h"
55 #include "basic-block.h"
56
57 #ifdef XCOFF_DEBUGGING_INFO
58 #include "xcoffout.h" /* Needed for external data
59 declarations for e.g. AIX 4.x. */
60 #endif
61
62 /* The (assembler) name of the first globally-visible object output. */
63 const char *first_global_object_name;
64 const char *weak_global_object_name;
65
66 struct addr_const;
67 struct constant_descriptor_rtx;
68 struct rtx_constant_pool;
69
70 struct varasm_status GTY(())
71 {
72 /* If we're using a per-function constant pool, this is it. */
73 struct rtx_constant_pool *pool;
74
75 /* Number of tree-constants deferred during the expansion of this
76 function. */
77 unsigned int deferred_constants;
78 };
79
80 #define n_deferred_constants (cfun->varasm->deferred_constants)
81
82 /* Number for making the label on the next
83 constant that is stored in memory. */
84
85 static GTY(()) int const_labelno;
86
87 /* Carry information from ASM_DECLARE_OBJECT_NAME
88 to ASM_FINISH_DECLARE_OBJECT. */
89
90 int size_directive_output;
91
92 /* The last decl for which assemble_variable was called,
93 if it did ASM_DECLARE_OBJECT_NAME.
94 If the last call to assemble_variable didn't do that,
95 this holds 0. */
96
97 tree last_assemble_variable_decl;
98
99 /* The following global variable indicates if the first basic block
100 in a function belongs to the cold partition or not. */
101
102 bool first_function_block_is_cold;
103
104 /* The following global variable indicates the label name to be put at
105 the start of the first cold section within each function, when
106 partitioning basic blocks into hot and cold sections. Used for
107 debug info. */
108
109 char *unlikely_section_label;
110
111 /* The following global variable indicates the label name to be put at
112 the start of the first hot section within each function, when
113 partitioning basic blocks into hot and cold sections. Used for
114 debug info. */
115
116 char *hot_section_label;
117
118 /* The following global variable indicates the label name to be put at
119 the end of the last hot section within each function, when
120 partitioning basic blocks into hot and cold sections. Used for
121 debug info. */
122
123 char *hot_section_end_label;
124
125 /* The following global variable indicates the label name to be put at
126 the end of the last cold section within each function, when
127 partitioning basic blocks into hot and cold sections. Used for
128 debug info.*/
129
130 char *cold_section_end_label;
131
132 /* The following global variable indicates the section name to be used
133 for the current cold section, when partitioning hot and cold basic
134 blocks into separate sections. */
135
136 char *unlikely_text_section_name;
137
138 /* We give all constants their own alias set. Perhaps redundant with
139 MEM_READONLY_P, but pre-dates it. */
140
141 static HOST_WIDE_INT const_alias_set;
142
143 static const char *strip_reg_name (const char *);
144 static int contains_pointers_p (tree);
145 #ifdef ASM_OUTPUT_EXTERNAL
146 static bool incorporeal_function_p (tree);
147 #endif
148 static void decode_addr_const (tree, struct addr_const *);
149 static hashval_t const_desc_hash (const void *);
150 static int const_desc_eq (const void *, const void *);
151 static hashval_t const_hash_1 (const tree);
152 static int compare_constant (const tree, const tree);
153 static tree copy_constant (tree);
154 static void output_constant_def_contents (rtx);
155 static void output_addressed_constants (tree);
156 static unsigned HOST_WIDE_INT array_size_for_constructor (tree);
157 static unsigned min_align (unsigned, unsigned);
158 static void output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int);
159 static void globalize_decl (tree);
160 static void maybe_assemble_visibility (tree);
161 static int in_named_entry_eq (const void *, const void *);
162 static hashval_t in_named_entry_hash (const void *);
163 static void initialize_cold_section_name (void);
164 #ifdef BSS_SECTION_ASM_OP
165 #ifdef ASM_OUTPUT_BSS
166 static void asm_output_bss (FILE *, tree, const char *,
167 unsigned HOST_WIDE_INT, unsigned HOST_WIDE_INT);
168 #endif
169 #ifdef ASM_OUTPUT_ALIGNED_BSS
170 static void asm_output_aligned_bss (FILE *, tree, const char *,
171 unsigned HOST_WIDE_INT, int)
172 ATTRIBUTE_UNUSED;
173 #endif
174 #endif /* BSS_SECTION_ASM_OP */
175 static bool asm_emit_uninitialised (tree, const char*,
176 unsigned HOST_WIDE_INT,
177 unsigned HOST_WIDE_INT);
178 static void mark_weak (tree);
179 \f
180 static GTY(()) enum in_section in_section = no_section;
181 enum in_section last_text_section;
182
183 /* Return a nonzero value if DECL has a section attribute. */
184 #ifndef IN_NAMED_SECTION
185 #define IN_NAMED_SECTION(DECL) \
186 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \
187 && DECL_SECTION_NAME (DECL) != NULL_TREE)
188 #endif
189
190 /* Text of section name when in_section == in_named. */
191 static GTY(()) const char *in_named_name;
192 const char *last_text_section_name;
193
194 /* Hash table of flags that have been used for a particular named section. */
195
196 struct in_named_entry GTY(())
197 {
198 const char *name;
199 unsigned int flags;
200 bool declared;
201 };
202
203 static GTY((param_is (struct in_named_entry))) htab_t in_named_htab;
204
205 /* Define functions like text_section for any extra sections. */
206 #ifdef EXTRA_SECTION_FUNCTIONS
207 EXTRA_SECTION_FUNCTIONS
208 #endif
209
210 static void
211 initialize_cold_section_name (void)
212 {
213 const char *name;
214 int len;
215
216 if (! unlikely_text_section_name)
217 {
218 if (DECL_SECTION_NAME (current_function_decl)
219 && (strcmp (TREE_STRING_POINTER (DECL_SECTION_NAME
220 (current_function_decl)),
221 HOT_TEXT_SECTION_NAME) != 0)
222 && (strcmp (TREE_STRING_POINTER (DECL_SECTION_NAME
223 (current_function_decl)),
224 UNLIKELY_EXECUTED_TEXT_SECTION_NAME) != 0))
225 {
226 name = TREE_STRING_POINTER (DECL_SECTION_NAME
227 (current_function_decl));
228 len = strlen (name);
229 unlikely_text_section_name = xmalloc (len + 10);
230 sprintf (unlikely_text_section_name, "%s%s", name, "_unlikely");
231 }
232 else
233 unlikely_text_section_name =
234 xstrdup (UNLIKELY_EXECUTED_TEXT_SECTION_NAME);
235 }
236 }
237
238 /* Tell assembler to switch to text section. */
239
240 void
241 text_section (void)
242 {
243 if (in_section != in_text)
244 {
245 in_section = in_text;
246 last_text_section = in_text;
247 fprintf (asm_out_file, "%s\n", TEXT_SECTION_ASM_OP);
248 }
249 }
250
251 /* Tell assembler to switch to unlikely-to-be-executed text section. */
252
253 void
254 unlikely_text_section (void)
255 {
256 if (! unlikely_text_section_name)
257 initialize_cold_section_name ();
258
259 if ((in_section != in_unlikely_executed_text)
260 && (in_section != in_named
261 || strcmp (in_named_name, unlikely_text_section_name) != 0))
262 {
263 named_section (NULL_TREE, unlikely_text_section_name, 0);
264 in_section = in_unlikely_executed_text;
265 last_text_section = in_unlikely_executed_text;
266 }
267 }
268
269 /* Tell assembler to switch to data section. */
270
271 void
272 data_section (void)
273 {
274 if (in_section != in_data)
275 {
276 in_section = in_data;
277 fprintf (asm_out_file, "%s\n", DATA_SECTION_ASM_OP);
278 }
279 }
280
281 /* Tell assembler to switch to read-only data section. This is normally
282 the text section. */
283
284 void
285 readonly_data_section (void)
286 {
287 #ifdef READONLY_DATA_SECTION
288 READONLY_DATA_SECTION (); /* Note this can call data_section. */
289 #else
290 #ifdef READONLY_DATA_SECTION_ASM_OP
291 if (in_section != in_readonly_data)
292 {
293 in_section = in_readonly_data;
294 fputs (READONLY_DATA_SECTION_ASM_OP, asm_out_file);
295 fputc ('\n', asm_out_file);
296 }
297 #else
298 text_section ();
299 #endif
300 #endif
301 }
302
303 /* Determine if we're in the text section. */
304
305 int
306 in_text_section (void)
307 {
308 return in_section == in_text;
309 }
310
311 /* Determine if we're in the unlikely-to-be-executed text section. */
312
313 int
314 in_unlikely_text_section (void)
315 {
316 bool ret_val;
317
318 ret_val = ((in_section == in_unlikely_executed_text)
319 || (in_section == in_named
320 && unlikely_text_section_name
321 && strcmp (in_named_name, unlikely_text_section_name) == 0));
322
323 return ret_val;
324 }
325
326 /* Determine if we're in the data section. */
327
328 int
329 in_data_section (void)
330 {
331 return in_section == in_data;
332 }
333
334 /* Helper routines for maintaining in_named_htab. */
335
336 static int
337 in_named_entry_eq (const void *p1, const void *p2)
338 {
339 const struct in_named_entry *old = p1;
340 const char *new = p2;
341
342 return strcmp (old->name, new) == 0;
343 }
344
345 static hashval_t
346 in_named_entry_hash (const void *p)
347 {
348 const struct in_named_entry *old = p;
349 return htab_hash_string (old->name);
350 }
351
352 /* If SECTION has been seen before as a named section, return the flags
353 that were used. Otherwise, return 0. Note, that 0 is a perfectly valid
354 set of flags for a section to have, so 0 does not mean that the section
355 has not been seen. */
356
357 static unsigned int
358 get_named_section_flags (const char *section)
359 {
360 struct in_named_entry **slot;
361
362 slot = (struct in_named_entry **)
363 htab_find_slot_with_hash (in_named_htab, section,
364 htab_hash_string (section), NO_INSERT);
365
366 return slot ? (*slot)->flags : 0;
367 }
368
369 /* Returns true if the section has been declared before. Sets internal
370 flag on this section in in_named_hash so subsequent calls on this
371 section will return false. */
372
373 bool
374 named_section_first_declaration (const char *name)
375 {
376 struct in_named_entry **slot;
377
378 slot = (struct in_named_entry **)
379 htab_find_slot_with_hash (in_named_htab, name,
380 htab_hash_string (name), NO_INSERT);
381 if (! (*slot)->declared)
382 {
383 (*slot)->declared = true;
384 return true;
385 }
386 else
387 {
388 return false;
389 }
390 }
391
392
393 /* Record FLAGS for SECTION. If SECTION was previously recorded with a
394 different set of flags, return false. */
395
396 bool
397 set_named_section_flags (const char *section, unsigned int flags)
398 {
399 struct in_named_entry **slot, *entry;
400
401 slot = (struct in_named_entry **)
402 htab_find_slot_with_hash (in_named_htab, section,
403 htab_hash_string (section), INSERT);
404 entry = *slot;
405
406 if (!entry)
407 {
408 entry = ggc_alloc (sizeof (*entry));
409 *slot = entry;
410 entry->name = ggc_strdup (section);
411 entry->flags = flags;
412 entry->declared = false;
413 }
414 else if (entry->flags != flags)
415 return false;
416
417 return true;
418 }
419
420 /* Tell assembler to change to section NAME with attributes FLAGS. If
421 DECL is non-NULL, it is the VAR_DECL or FUNCTION_DECL with which
422 this section is associated. */
423
424 void
425 named_section_real (const char *name, unsigned int flags, tree decl)
426 {
427 if (in_section != in_named || strcmp (name, in_named_name) != 0)
428 {
429 bool unchanged = set_named_section_flags (name, flags);
430
431 gcc_assert (unchanged);
432
433 targetm.asm_out.named_section (name, flags, decl);
434
435 if (flags & SECTION_FORGET)
436 in_section = no_section;
437 else
438 {
439 in_named_name = ggc_strdup (name);
440 in_section = in_named;
441 }
442 }
443
444 if (in_text_section () || in_unlikely_text_section ())
445 {
446 last_text_section = in_section;
447 last_text_section_name = name;
448 }
449 }
450
451 /* Tell assembler to change to section NAME for DECL.
452 If DECL is NULL, just switch to section NAME.
453 If NAME is NULL, get the name from DECL.
454 If RELOC is 1, the initializer for DECL contains relocs. */
455
456 void
457 named_section (tree decl, const char *name, int reloc)
458 {
459 unsigned int flags;
460
461 gcc_assert (!decl || DECL_P (decl));
462 if (name == NULL)
463 name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
464
465 if (strcmp (name, UNLIKELY_EXECUTED_TEXT_SECTION_NAME) == 0
466 && !unlikely_text_section_name)
467 unlikely_text_section_name =
468 xstrdup (UNLIKELY_EXECUTED_TEXT_SECTION_NAME);
469
470 flags = targetm.section_type_flags (decl, name, reloc);
471
472 /* Sanity check user variables for flag changes. Non-user
473 section flag changes will die in named_section_flags.
474 However, don't complain if SECTION_OVERRIDE is set.
475 We trust that the setter knows that it is safe to ignore
476 the default flags for this decl. */
477 if (decl && ! set_named_section_flags (name, flags))
478 {
479 flags = get_named_section_flags (name);
480 if ((flags & SECTION_OVERRIDE) == 0)
481 error ("%J%D causes a section type conflict", decl, decl);
482 }
483
484 named_section_real (name, flags, decl);
485 }
486
487 /* If required, set DECL_SECTION_NAME to a unique name. */
488
489 void
490 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
491 int flag_function_or_data_sections)
492 {
493 if (DECL_SECTION_NAME (decl) == NULL_TREE
494 && targetm.have_named_sections
495 && (flag_function_or_data_sections
496 || DECL_ONE_ONLY (decl)))
497 targetm.asm_out.unique_section (decl, reloc);
498 }
499
500 #ifdef BSS_SECTION_ASM_OP
501
502 /* Tell the assembler to switch to the bss section. */
503
504 void
505 bss_section (void)
506 {
507 if (in_section != in_bss)
508 {
509 fprintf (asm_out_file, "%s\n", BSS_SECTION_ASM_OP);
510 in_section = in_bss;
511 }
512 }
513
514 #ifdef ASM_OUTPUT_BSS
515
516 /* Utility function for ASM_OUTPUT_BSS for targets to use if
517 they don't support alignments in .bss.
518 ??? It is believed that this function will work in most cases so such
519 support is localized here. */
520
521 static void
522 asm_output_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
523 const char *name,
524 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
525 unsigned HOST_WIDE_INT rounded)
526 {
527 targetm.asm_out.globalize_label (file, name);
528 bss_section ();
529 #ifdef ASM_DECLARE_OBJECT_NAME
530 last_assemble_variable_decl = decl;
531 ASM_DECLARE_OBJECT_NAME (file, name, decl);
532 #else
533 /* Standard thing is just output label for the object. */
534 ASM_OUTPUT_LABEL (file, name);
535 #endif /* ASM_DECLARE_OBJECT_NAME */
536 ASM_OUTPUT_SKIP (file, rounded ? rounded : 1);
537 }
538
539 #endif
540
541 #ifdef ASM_OUTPUT_ALIGNED_BSS
542
543 /* Utility function for targets to use in implementing
544 ASM_OUTPUT_ALIGNED_BSS.
545 ??? It is believed that this function will work in most cases so such
546 support is localized here. */
547
548 static void
549 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
550 const char *name, unsigned HOST_WIDE_INT size,
551 int align)
552 {
553 bss_section ();
554 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
555 #ifdef ASM_DECLARE_OBJECT_NAME
556 last_assemble_variable_decl = decl;
557 ASM_DECLARE_OBJECT_NAME (file, name, decl);
558 #else
559 /* Standard thing is just output label for the object. */
560 ASM_OUTPUT_LABEL (file, name);
561 #endif /* ASM_DECLARE_OBJECT_NAME */
562 ASM_OUTPUT_SKIP (file, size ? size : 1);
563 }
564
565 #endif
566
567 #endif /* BSS_SECTION_ASM_OP */
568
569 /* Switch to the section for function DECL.
570
571 If DECL is NULL_TREE, switch to the text section. We can be passed
572 NULL_TREE under some circumstances by dbxout.c at least. */
573
574 void
575 function_section (tree decl)
576 {
577 bool unlikely = false;
578
579 if (first_function_block_is_cold)
580 unlikely = true;
581
582 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
583 targetm.asm_out.select_section (decl, unlikely, DECL_ALIGN (decl));
584 #else
585 if (decl != NULL_TREE
586 && DECL_SECTION_NAME (decl) != NULL_TREE)
587 named_section (decl, (char *) 0, 0);
588 else
589 text_section ();
590 #endif
591 }
592
593 void
594 current_function_section (tree decl)
595 {
596 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
597 bool unlikely = (in_unlikely_text_section ()
598 || (last_text_section == in_unlikely_executed_text));
599
600 targetm.asm_out.select_section (decl, unlikely, DECL_ALIGN (decl));
601 #else
602 if (last_text_section == in_unlikely_executed_text)
603 unlikely_text_section ();
604 else if (last_text_section == in_text)
605 text_section ();
606 else if (last_text_section == in_named)
607 named_section (NULL_TREE, last_text_section_name, 0);
608 else
609 function_section (decl);
610 #endif
611 }
612
613 /* Switch to read-only data section associated with function DECL. */
614
615 void
616 default_function_rodata_section (tree decl)
617 {
618 if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
619 {
620 const char *name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
621
622 /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo. */
623 if (DECL_ONE_ONLY (decl) && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
624 {
625 size_t len = strlen (name) + 1;
626 char *rname = alloca (len);
627
628 memcpy (rname, name, len);
629 rname[14] = 'r';
630 named_section_real (rname, SECTION_LINKONCE, decl);
631 return;
632 }
633 /* For .text.foo we want to use .rodata.foo. */
634 else if (flag_function_sections && flag_data_sections
635 && strncmp (name, ".text.", 6) == 0)
636 {
637 size_t len = strlen (name) + 1;
638 char *rname = alloca (len + 2);
639
640 memcpy (rname, ".rodata", 7);
641 memcpy (rname + 7, name + 5, len - 5);
642 named_section_flags (rname, 0);
643 return;
644 }
645 }
646
647 readonly_data_section ();
648 }
649
650 /* Switch to read-only data section associated with function DECL
651 for targets where that section should be always the single
652 readonly data section. */
653
654 void
655 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
656 {
657 readonly_data_section ();
658 }
659
660 /* Switch to section for variable DECL. RELOC is the same as the
661 argument to SELECT_SECTION. */
662
663 void
664 variable_section (tree decl, int reloc)
665 {
666 if (IN_NAMED_SECTION (decl))
667 named_section (decl, NULL, reloc);
668 else
669 targetm.asm_out.select_section (decl, reloc, DECL_ALIGN (decl));
670 }
671
672 /* Tell assembler to switch to the section for string merging. */
673
674 void
675 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
676 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
677 unsigned int flags ATTRIBUTE_UNUSED)
678 {
679 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
680 && TREE_CODE (decl) == STRING_CST
681 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
682 && align <= 256
683 && TREE_STRING_LENGTH (decl) >= int_size_in_bytes (TREE_TYPE (decl)))
684 {
685 enum machine_mode mode;
686 unsigned int modesize;
687 const char *str;
688 int i, j, len, unit;
689 char name[30];
690
691 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
692 modesize = GET_MODE_BITSIZE (mode);
693 if (modesize >= 8 && modesize <= 256
694 && (modesize & (modesize - 1)) == 0)
695 {
696 if (align < modesize)
697 align = modesize;
698
699 str = TREE_STRING_POINTER (decl);
700 len = TREE_STRING_LENGTH (decl);
701 unit = GET_MODE_SIZE (mode);
702
703 /* Check for embedded NUL characters. */
704 for (i = 0; i < len; i += unit)
705 {
706 for (j = 0; j < unit; j++)
707 if (str[i + j] != '\0')
708 break;
709 if (j == unit)
710 break;
711 }
712 if (i == len - unit)
713 {
714 sprintf (name, ".rodata.str%d.%d", modesize / 8,
715 (int) (align / 8));
716 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
717 if (!i && modesize < align)
718 {
719 /* A "" string with requested alignment greater than
720 character size might cause a problem:
721 if some other string required even bigger
722 alignment than "", then linker might think the
723 "" is just part of padding after some other string
724 and not put it into the hash table initially.
725 But this means "" could have smaller alignment
726 than requested. */
727 #ifdef ASM_OUTPUT_SECTION_START
728 named_section_flags (name, flags);
729 ASM_OUTPUT_SECTION_START (asm_out_file);
730 #else
731 readonly_data_section ();
732 #endif
733 return;
734 }
735
736 named_section_flags (name, flags);
737 return;
738 }
739 }
740 }
741
742 readonly_data_section ();
743 }
744
745 /* Tell assembler to switch to the section for constant merging. */
746
747 void
748 mergeable_constant_section (enum machine_mode mode ATTRIBUTE_UNUSED,
749 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
750 unsigned int flags ATTRIBUTE_UNUSED)
751 {
752 unsigned int modesize = GET_MODE_BITSIZE (mode);
753
754 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
755 && mode != VOIDmode
756 && mode != BLKmode
757 && modesize <= align
758 && align >= 8
759 && align <= 256
760 && (align & (align - 1)) == 0)
761 {
762 char name[24];
763
764 sprintf (name, ".rodata.cst%d", (int) (align / 8));
765 flags |= (align / 8) | SECTION_MERGE;
766 named_section_flags (name, flags);
767 return;
768 }
769
770 readonly_data_section ();
771 }
772 \f
773 /* Given NAME, a putative register name, discard any customary prefixes. */
774
775 static const char *
776 strip_reg_name (const char *name)
777 {
778 #ifdef REGISTER_PREFIX
779 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
780 name += strlen (REGISTER_PREFIX);
781 #endif
782 if (name[0] == '%' || name[0] == '#')
783 name++;
784 return name;
785 }
786 \f
787 /* The user has asked for a DECL to have a particular name. Set (or
788 change) it in such a way that we don't prefix an underscore to
789 it. */
790 void
791 set_user_assembler_name (tree decl, const char *name)
792 {
793 char *starred = alloca (strlen (name) + 2);
794 starred[0] = '*';
795 strcpy (starred + 1, name);
796 change_decl_assembler_name (decl, get_identifier (starred));
797 SET_DECL_RTL (decl, NULL_RTX);
798 }
799 \f
800 /* Decode an `asm' spec for a declaration as a register name.
801 Return the register number, or -1 if nothing specified,
802 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
803 or -3 if ASMSPEC is `cc' and is not recognized,
804 or -4 if ASMSPEC is `memory' and is not recognized.
805 Accept an exact spelling or a decimal number.
806 Prefixes such as % are optional. */
807
808 int
809 decode_reg_name (const char *asmspec)
810 {
811 if (asmspec != 0)
812 {
813 int i;
814
815 /* Get rid of confusing prefixes. */
816 asmspec = strip_reg_name (asmspec);
817
818 /* Allow a decimal number as a "register name". */
819 for (i = strlen (asmspec) - 1; i >= 0; i--)
820 if (! ISDIGIT (asmspec[i]))
821 break;
822 if (asmspec[0] != 0 && i < 0)
823 {
824 i = atoi (asmspec);
825 if (i < FIRST_PSEUDO_REGISTER && i >= 0)
826 return i;
827 else
828 return -2;
829 }
830
831 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
832 if (reg_names[i][0]
833 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
834 return i;
835
836 #ifdef ADDITIONAL_REGISTER_NAMES
837 {
838 static const struct { const char *const name; const int number; } table[]
839 = ADDITIONAL_REGISTER_NAMES;
840
841 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
842 if (! strcmp (asmspec, table[i].name))
843 return table[i].number;
844 }
845 #endif /* ADDITIONAL_REGISTER_NAMES */
846
847 if (!strcmp (asmspec, "memory"))
848 return -4;
849
850 if (!strcmp (asmspec, "cc"))
851 return -3;
852
853 return -2;
854 }
855
856 return -1;
857 }
858 \f
859 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
860 have static storage duration. In other words, it should not be an
861 automatic variable, including PARM_DECLs.
862
863 There is, however, one exception: this function handles variables
864 explicitly placed in a particular register by the user.
865
866 This is never called for PARM_DECL nodes. */
867
868 void
869 make_decl_rtl (tree decl)
870 {
871 const char *name = 0;
872 int reg_number;
873 rtx x;
874
875 /* Check that we are not being given an automatic variable. */
876 gcc_assert (TREE_CODE (decl) != PARM_DECL
877 && TREE_CODE (decl) != RESULT_DECL);
878
879 /* A weak alias has TREE_PUBLIC set but not the other bits. */
880 gcc_assert (TREE_CODE (decl) != VAR_DECL
881 || TREE_STATIC (decl)
882 || TREE_PUBLIC (decl)
883 || DECL_EXTERNAL (decl)
884 || DECL_REGISTER (decl));
885
886 /* And that we were not given a type or a label. */
887 gcc_assert (TREE_CODE (decl) != TYPE_DECL
888 && TREE_CODE (decl) != LABEL_DECL);
889
890 /* For a duplicate declaration, we can be called twice on the
891 same DECL node. Don't discard the RTL already made. */
892 if (DECL_RTL_SET_P (decl))
893 {
894 /* If the old RTL had the wrong mode, fix the mode. */
895 if (GET_MODE (DECL_RTL (decl)) != DECL_MODE (decl))
896 SET_DECL_RTL (decl, adjust_address_nv (DECL_RTL (decl),
897 DECL_MODE (decl), 0));
898
899 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
900 return;
901
902 /* ??? Another way to do this would be to maintain a hashed
903 table of such critters. Instead of adding stuff to a DECL
904 to give certain attributes to it, we could use an external
905 hash map from DECL to set of attributes. */
906
907 /* Let the target reassign the RTL if it wants.
908 This is necessary, for example, when one machine specific
909 decl attribute overrides another. */
910 targetm.encode_section_info (decl, DECL_RTL (decl), false);
911
912 /* Make this function static known to the mudflap runtime. */
913 if (flag_mudflap && TREE_CODE (decl) == VAR_DECL)
914 mudflap_enqueue_decl (decl);
915
916 return;
917 }
918
919 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
920
921 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
922 {
923 reg_number = decode_reg_name (name);
924 /* First detect errors in declaring global registers. */
925 if (reg_number == -1)
926 error ("%Jregister name not specified for %qD", decl, decl);
927 else if (reg_number < 0)
928 error ("%Jinvalid register name for %qD", decl, decl);
929 else if (TYPE_MODE (TREE_TYPE (decl)) == BLKmode)
930 error ("%Jdata type of %qD isn%'t suitable for a register",
931 decl, decl);
932 else if (! HARD_REGNO_MODE_OK (reg_number, TYPE_MODE (TREE_TYPE (decl))))
933 error ("%Jregister specified for %qD isn%'t suitable for data type",
934 decl, decl);
935 /* Now handle properly declared static register variables. */
936 else
937 {
938 int nregs;
939
940 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
941 {
942 DECL_INITIAL (decl) = 0;
943 error ("global register variable has initial value");
944 }
945 if (TREE_THIS_VOLATILE (decl))
946 warning ("volatile register variables don%'t "
947 "work as you might wish");
948
949 /* If the user specified one of the eliminables registers here,
950 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
951 confused with that register and be eliminated. This usage is
952 somewhat suspect... */
953
954 SET_DECL_RTL (decl, gen_rtx_raw_REG (DECL_MODE (decl), reg_number));
955 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
956 REG_USERVAR_P (DECL_RTL (decl)) = 1;
957
958 if (TREE_STATIC (decl))
959 {
960 /* Make this register global, so not usable for anything
961 else. */
962 #ifdef ASM_DECLARE_REGISTER_GLOBAL
963 name = IDENTIFIER_POINTER (DECL_NAME (decl));
964 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
965 #endif
966 nregs = hard_regno_nregs[reg_number][DECL_MODE (decl)];
967 while (nregs > 0)
968 globalize_reg (reg_number + --nregs);
969 }
970
971 /* As a register variable, it has no section. */
972 return;
973 }
974 }
975 /* Now handle ordinary static variables and functions (in memory).
976 Also handle vars declared register invalidly. */
977 else if (name[0] == '*')
978 {
979 #ifdef REGISTER_PREFIX
980 if (strlen (REGISTER_PREFIX) != 0)
981 {
982 reg_number = decode_reg_name (name);
983 if (reg_number >= 0 || reg_number == -3)
984 error ("%Jregister name given for non-register variable %qD", decl, decl);
985 }
986 #endif
987 }
988
989 /* Specifying a section attribute on a variable forces it into a
990 non-.bss section, and thus it cannot be common. */
991 if (TREE_CODE (decl) == VAR_DECL
992 && DECL_SECTION_NAME (decl) != NULL_TREE
993 && DECL_INITIAL (decl) == NULL_TREE
994 && DECL_COMMON (decl))
995 DECL_COMMON (decl) = 0;
996
997 /* Variables can't be both common and weak. */
998 if (TREE_CODE (decl) == VAR_DECL && DECL_WEAK (decl))
999 DECL_COMMON (decl) = 0;
1000
1001 x = gen_rtx_SYMBOL_REF (Pmode, name);
1002 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
1003 SYMBOL_REF_DECL (x) = decl;
1004
1005 x = gen_rtx_MEM (DECL_MODE (decl), x);
1006 if (TREE_CODE (decl) != FUNCTION_DECL)
1007 set_mem_attributes (x, decl, 1);
1008 SET_DECL_RTL (decl, x);
1009
1010 /* Optionally set flags or add text to the name to record information
1011 such as that it is a function name.
1012 If the name is changed, the macro ASM_OUTPUT_LABELREF
1013 will have to know how to strip this information. */
1014 targetm.encode_section_info (decl, DECL_RTL (decl), true);
1015
1016 /* Make this function static known to the mudflap runtime. */
1017 if (flag_mudflap && TREE_CODE (decl) == VAR_DECL)
1018 mudflap_enqueue_decl (decl);
1019 }
1020
1021 /* Make the rtl for variable VAR be volatile.
1022 Use this only for static variables. */
1023
1024 void
1025 make_var_volatile (tree var)
1026 {
1027 gcc_assert (MEM_P (DECL_RTL (var)));
1028
1029 MEM_VOLATILE_P (DECL_RTL (var)) = 1;
1030 }
1031 \f
1032 /* Output a string of literal assembler code
1033 for an `asm' keyword used between functions. */
1034
1035 void
1036 assemble_asm (tree string)
1037 {
1038 app_enable ();
1039
1040 if (TREE_CODE (string) == ADDR_EXPR)
1041 string = TREE_OPERAND (string, 0);
1042
1043 fprintf (asm_out_file, "\t%s\n", TREE_STRING_POINTER (string));
1044 }
1045
1046 /* Record an element in the table of global destructors. SYMBOL is
1047 a SYMBOL_REF of the function to be called; PRIORITY is a number
1048 between 0 and MAX_INIT_PRIORITY. */
1049
1050 void
1051 default_stabs_asm_out_destructor (rtx symbol ATTRIBUTE_UNUSED,
1052 int priority ATTRIBUTE_UNUSED)
1053 {
1054 #if defined DBX_DEBUGGING_INFO || defined XCOFF_DEBUGGING_INFO
1055 /* Tell GNU LD that this is part of the static destructor set.
1056 This will work for any system that uses stabs, most usefully
1057 aout systems. */
1058 dbxout_begin_simple_stabs ("___DTOR_LIST__", 22 /* N_SETT */);
1059 dbxout_stab_value_label (XSTR (symbol, 0));
1060 #else
1061 sorry ("global destructors not supported on this target");
1062 #endif
1063 }
1064
1065 void
1066 default_named_section_asm_out_destructor (rtx symbol, int priority)
1067 {
1068 const char *section = ".dtors";
1069 char buf[16];
1070
1071 /* ??? This only works reliably with the GNU linker. */
1072 if (priority != DEFAULT_INIT_PRIORITY)
1073 {
1074 sprintf (buf, ".dtors.%.5u",
1075 /* Invert the numbering so the linker puts us in the proper
1076 order; constructors are run from right to left, and the
1077 linker sorts in increasing order. */
1078 MAX_INIT_PRIORITY - priority);
1079 section = buf;
1080 }
1081
1082 named_section_flags (section, SECTION_WRITE);
1083 assemble_align (POINTER_SIZE);
1084 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1085 }
1086
1087 #ifdef DTORS_SECTION_ASM_OP
1088 void
1089 dtors_section (void)
1090 {
1091 if (in_section != in_dtors)
1092 {
1093 in_section = in_dtors;
1094 fputs (DTORS_SECTION_ASM_OP, asm_out_file);
1095 fputc ('\n', asm_out_file);
1096 }
1097 }
1098
1099 void
1100 default_dtor_section_asm_out_destructor (rtx symbol,
1101 int priority ATTRIBUTE_UNUSED)
1102 {
1103 dtors_section ();
1104 assemble_align (POINTER_SIZE);
1105 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1106 }
1107 #endif
1108
1109 /* Likewise for global constructors. */
1110
1111 void
1112 default_stabs_asm_out_constructor (rtx symbol ATTRIBUTE_UNUSED,
1113 int priority ATTRIBUTE_UNUSED)
1114 {
1115 #if defined DBX_DEBUGGING_INFO || defined XCOFF_DEBUGGING_INFO
1116 /* Tell GNU LD that this is part of the static destructor set.
1117 This will work for any system that uses stabs, most usefully
1118 aout systems. */
1119 dbxout_begin_simple_stabs ("___CTOR_LIST__", 22 /* N_SETT */);
1120 dbxout_stab_value_label (XSTR (symbol, 0));
1121 #else
1122 sorry ("global constructors not supported on this target");
1123 #endif
1124 }
1125
1126 void
1127 default_named_section_asm_out_constructor (rtx symbol, int priority)
1128 {
1129 const char *section = ".ctors";
1130 char buf[16];
1131
1132 /* ??? This only works reliably with the GNU linker. */
1133 if (priority != DEFAULT_INIT_PRIORITY)
1134 {
1135 sprintf (buf, ".ctors.%.5u",
1136 /* Invert the numbering so the linker puts us in the proper
1137 order; constructors are run from right to left, and the
1138 linker sorts in increasing order. */
1139 MAX_INIT_PRIORITY - priority);
1140 section = buf;
1141 }
1142
1143 named_section_flags (section, SECTION_WRITE);
1144 assemble_align (POINTER_SIZE);
1145 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1146 }
1147
1148 #ifdef CTORS_SECTION_ASM_OP
1149 void
1150 ctors_section (void)
1151 {
1152 if (in_section != in_ctors)
1153 {
1154 in_section = in_ctors;
1155 fputs (CTORS_SECTION_ASM_OP, asm_out_file);
1156 fputc ('\n', asm_out_file);
1157 }
1158 }
1159
1160 void
1161 default_ctor_section_asm_out_constructor (rtx symbol,
1162 int priority ATTRIBUTE_UNUSED)
1163 {
1164 ctors_section ();
1165 assemble_align (POINTER_SIZE);
1166 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1167 }
1168 #endif
1169 \f
1170 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1171 a nonzero value if the constant pool should be output before the
1172 start of the function, or a zero value if the pool should output
1173 after the end of the function. The default is to put it before the
1174 start. */
1175
1176 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1177 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1178 #endif
1179
1180 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1181 to be output to assembler.
1182 Set first_global_object_name and weak_global_object_name as appropriate. */
1183
1184 void
1185 notice_global_symbol (tree decl)
1186 {
1187 const char **type = &first_global_object_name;
1188
1189 if (first_global_object_name
1190 || !TREE_PUBLIC (decl) || DECL_EXTERNAL (decl)
1191 || !DECL_NAME (decl)
1192 || (TREE_CODE (decl) != FUNCTION_DECL
1193 && (TREE_CODE (decl) != VAR_DECL
1194 || (DECL_COMMON (decl)
1195 && (DECL_INITIAL (decl) == 0
1196 || DECL_INITIAL (decl) == error_mark_node))))
1197 || !MEM_P (DECL_RTL (decl)))
1198 return;
1199
1200 /* We win when global object is found, but it is useful to know about weak
1201 symbol as well so we can produce nicer unique names. */
1202 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl))
1203 type = &weak_global_object_name;
1204
1205 if (!*type)
1206 {
1207 const char *p;
1208 char *name;
1209 rtx decl_rtl = DECL_RTL (decl);
1210
1211 p = targetm.strip_name_encoding (XSTR (XEXP (decl_rtl, 0), 0));
1212 name = xstrdup (p);
1213
1214 *type = name;
1215 }
1216 }
1217
1218 /* Output assembler code for the constant pool of a function and associated
1219 with defining the name of the function. DECL describes the function.
1220 NAME is the function's name. For the constant pool, we use the current
1221 constant pool data. */
1222
1223 void
1224 assemble_start_function (tree decl, const char *fnname)
1225 {
1226 int align;
1227 bool hot_label_written = false;
1228
1229 unlikely_text_section_name = NULL;
1230
1231 first_function_block_is_cold = false;
1232 hot_section_label = reconcat (hot_section_label, fnname, ".hot_section", NULL);
1233 unlikely_section_label = reconcat (unlikely_section_label,
1234 fnname, ".unlikely_section", NULL);
1235 hot_section_end_label = reconcat (hot_section_end_label,
1236 fnname, ".end", NULL);
1237 cold_section_end_label = reconcat (cold_section_end_label,
1238 fnname, ".end.cold", NULL);
1239
1240 /* The following code does not need preprocessing in the assembler. */
1241
1242 app_disable ();
1243
1244 if (CONSTANT_POOL_BEFORE_FUNCTION)
1245 output_constant_pool (fnname, decl);
1246
1247 /* Make sure the not and cold text (code) sections are properly
1248 aligned. This is necessary here in the case where the function
1249 has both hot and cold sections, because we don't want to re-set
1250 the alignment when the section switch happens mid-function. */
1251
1252 if (flag_reorder_blocks_and_partition)
1253 {
1254 unlikely_text_section ();
1255 assemble_align (FUNCTION_BOUNDARY);
1256 ASM_OUTPUT_LABEL (asm_out_file, unlikely_section_label);
1257 if (BB_PARTITION (ENTRY_BLOCK_PTR->next_bb) == BB_COLD_PARTITION)
1258 {
1259 /* Since the function starts with a cold section, we need to
1260 explicitly align the hot section and write out the hot
1261 section label. */
1262 text_section ();
1263 assemble_align (FUNCTION_BOUNDARY);
1264 ASM_OUTPUT_LABEL (asm_out_file, hot_section_label);
1265 hot_label_written = true;
1266 first_function_block_is_cold = true;
1267 }
1268 }
1269 else if (DECL_SECTION_NAME (decl))
1270 {
1271 /* Calls to function_section rely on first_function_block_is_cold
1272 being accurate. The first block may be cold even if we aren't
1273 doing partitioning, if the entire function was decided by
1274 choose_function_section (predict.c) to be cold. */
1275
1276 int i;
1277 int len;
1278 char *s;
1279
1280 initialize_cold_section_name ();
1281
1282 /* The following is necessary, because 'strcmp
1283 (TREE_STRING_POINTER (DECL_SECTION_NAME (decl)), blah)' always
1284 fails, presumably because TREE_STRING_POINTER is declared to
1285 be an array of size 1 of char. */
1286
1287 len = TREE_STRING_LENGTH (DECL_SECTION_NAME (decl));
1288 s = (char *) xmalloc (len + 1);
1289
1290 for (i = 0; i < len; i ++)
1291 s[i] = (TREE_STRING_POINTER (DECL_SECTION_NAME (decl)))[i];
1292 s[len] = '\0';
1293
1294 if (unlikely_text_section_name
1295 && (strcmp (s, unlikely_text_section_name) == 0))
1296 first_function_block_is_cold = true;
1297 }
1298
1299 last_text_section = no_section;
1300 resolve_unique_section (decl, 0, flag_function_sections);
1301
1302 /* Switch to the correct text section for the start of the function. */
1303
1304 function_section (decl);
1305 if (flag_reorder_blocks_and_partition
1306 && !hot_label_written)
1307 ASM_OUTPUT_LABEL (asm_out_file, hot_section_label);
1308
1309 /* Tell assembler to move to target machine's alignment for functions. */
1310 align = floor_log2 (FUNCTION_BOUNDARY / BITS_PER_UNIT);
1311 if (align < force_align_functions_log)
1312 align = force_align_functions_log;
1313 if (align > 0)
1314 {
1315 ASM_OUTPUT_ALIGN (asm_out_file, align);
1316 }
1317
1318 /* Handle a user-specified function alignment.
1319 Note that we still need to align to FUNCTION_BOUNDARY, as above,
1320 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1321 if (align_functions_log > align
1322 && cfun->function_frequency != FUNCTION_FREQUENCY_UNLIKELY_EXECUTED)
1323 {
1324 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1325 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1326 align_functions_log, align_functions - 1);
1327 #else
1328 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1329 #endif
1330 }
1331
1332 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1333 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1334 #endif
1335
1336 (*debug_hooks->begin_function) (decl);
1337
1338 /* Make function name accessible from other files, if appropriate. */
1339
1340 if (TREE_PUBLIC (decl))
1341 {
1342 notice_global_symbol (decl);
1343
1344 globalize_decl (decl);
1345
1346 maybe_assemble_visibility (decl);
1347 }
1348
1349 if (DECL_PRESERVE_P (decl))
1350 targetm.asm_out.mark_decl_preserved (fnname);
1351
1352 /* Do any machine/system dependent processing of the function name. */
1353 #ifdef ASM_DECLARE_FUNCTION_NAME
1354 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1355 #else
1356 /* Standard thing is just output label for the function. */
1357 ASM_OUTPUT_LABEL (asm_out_file, fnname);
1358 #endif /* ASM_DECLARE_FUNCTION_NAME */
1359
1360 insert_section_boundary_note ();
1361 }
1362
1363 /* Output assembler code associated with defining the size of the
1364 function. DECL describes the function. NAME is the function's name. */
1365
1366 void
1367 assemble_end_function (tree decl, const char *fnname)
1368 {
1369 enum in_section save_text_section;
1370 #ifdef ASM_DECLARE_FUNCTION_SIZE
1371 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1372 #endif
1373 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1374 {
1375 output_constant_pool (fnname, decl);
1376 function_section (decl); /* need to switch back */
1377 }
1378 /* Output labels for end of hot/cold text sections (to be used by
1379 debug info.) */
1380 if (flag_reorder_blocks_and_partition)
1381 {
1382 save_text_section = in_section;
1383 unlikely_text_section ();
1384 ASM_OUTPUT_LABEL (asm_out_file, cold_section_end_label);
1385 text_section ();
1386 ASM_OUTPUT_LABEL (asm_out_file, hot_section_end_label);
1387 if (save_text_section == in_unlikely_executed_text)
1388 unlikely_text_section ();
1389 }
1390 }
1391 \f
1392 /* Assemble code to leave SIZE bytes of zeros. */
1393
1394 void
1395 assemble_zeros (unsigned HOST_WIDE_INT size)
1396 {
1397 /* Do no output if -fsyntax-only. */
1398 if (flag_syntax_only)
1399 return;
1400
1401 #ifdef ASM_NO_SKIP_IN_TEXT
1402 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1403 so we must output 0s explicitly in the text section. */
1404 if ((ASM_NO_SKIP_IN_TEXT && in_text_section ())
1405 || (ASM_NO_SKIP_IN_TEXT && in_unlikely_text_section ()))
1406 {
1407 unsigned HOST_WIDE_INT i;
1408 for (i = 0; i < size; i++)
1409 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1410 }
1411 else
1412 #endif
1413 if (size > 0)
1414 ASM_OUTPUT_SKIP (asm_out_file, size);
1415 }
1416
1417 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1418
1419 void
1420 assemble_align (int align)
1421 {
1422 if (align > BITS_PER_UNIT)
1423 {
1424 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1425 }
1426 }
1427
1428 /* Assemble a string constant with the specified C string as contents. */
1429
1430 void
1431 assemble_string (const char *p, int size)
1432 {
1433 int pos = 0;
1434 int maximum = 2000;
1435
1436 /* If the string is very long, split it up. */
1437
1438 while (pos < size)
1439 {
1440 int thissize = size - pos;
1441 if (thissize > maximum)
1442 thissize = maximum;
1443
1444 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1445
1446 pos += thissize;
1447 p += thissize;
1448 }
1449 }
1450
1451 \f
1452 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1453 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1454 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1455 #else
1456 #if defined ASM_OUTPUT_ALIGNED_LOCAL
1457 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1458 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, DECL_ALIGN (decl))
1459 #else
1460 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1461 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded)
1462 #endif
1463 #endif
1464
1465 #if defined ASM_OUTPUT_ALIGNED_BSS
1466 #define ASM_EMIT_BSS(decl, name, size, rounded) \
1467 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1468 #else
1469 #if defined ASM_OUTPUT_BSS
1470 #define ASM_EMIT_BSS(decl, name, size, rounded) \
1471 ASM_OUTPUT_BSS (asm_out_file, decl, name, size, rounded)
1472 #else
1473 #undef ASM_EMIT_BSS
1474 #endif
1475 #endif
1476
1477 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1478 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1479 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1480 #else
1481 #if defined ASM_OUTPUT_ALIGNED_COMMON
1482 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1483 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size, DECL_ALIGN (decl))
1484 #else
1485 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1486 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded)
1487 #endif
1488 #endif
1489
1490 static bool
1491 asm_emit_uninitialised (tree decl, const char *name,
1492 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1493 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1494 {
1495 enum
1496 {
1497 asm_dest_common,
1498 asm_dest_bss,
1499 asm_dest_local
1500 }
1501 destination = asm_dest_local;
1502
1503 /* ??? We should handle .bss via select_section mechanisms rather than
1504 via special target hooks. That would eliminate this special case. */
1505 if (TREE_PUBLIC (decl))
1506 {
1507 if (!DECL_COMMON (decl))
1508 #ifdef ASM_EMIT_BSS
1509 destination = asm_dest_bss;
1510 #else
1511 return false;
1512 #endif
1513 else
1514 destination = asm_dest_common;
1515 }
1516
1517 if (destination != asm_dest_common)
1518 {
1519 resolve_unique_section (decl, 0, flag_data_sections);
1520 /* Custom sections don't belong here. */
1521 if (DECL_SECTION_NAME (decl))
1522 return false;
1523 }
1524
1525 if (destination == asm_dest_bss)
1526 globalize_decl (decl);
1527
1528 if (flag_shared_data)
1529 {
1530 switch (destination)
1531 {
1532 #ifdef ASM_OUTPUT_SHARED_BSS
1533 case asm_dest_bss:
1534 ASM_OUTPUT_SHARED_BSS (asm_out_file, decl, name, size, rounded);
1535 return;
1536 #endif
1537 #ifdef ASM_OUTPUT_SHARED_COMMON
1538 case asm_dest_common:
1539 ASM_OUTPUT_SHARED_COMMON (asm_out_file, name, size, rounded);
1540 return;
1541 #endif
1542 #ifdef ASM_OUTPUT_SHARED_LOCAL
1543 case asm_dest_local:
1544 ASM_OUTPUT_SHARED_LOCAL (asm_out_file, name, size, rounded);
1545 return;
1546 #endif
1547 default:
1548 break;
1549 }
1550 }
1551
1552 switch (destination)
1553 {
1554 #ifdef ASM_EMIT_BSS
1555 case asm_dest_bss:
1556 ASM_EMIT_BSS (decl, name, size, rounded);
1557 break;
1558 #endif
1559 case asm_dest_common:
1560 ASM_EMIT_COMMON (decl, name, size, rounded);
1561 break;
1562 case asm_dest_local:
1563 ASM_EMIT_LOCAL (decl, name, size, rounded);
1564 break;
1565 default:
1566 gcc_unreachable ();
1567 }
1568
1569 return true;
1570 }
1571
1572 /* Assemble everything that is needed for a variable or function declaration.
1573 Not used for automatic variables, and not used for function definitions.
1574 Should not be called for variables of incomplete structure type.
1575
1576 TOP_LEVEL is nonzero if this variable has file scope.
1577 AT_END is nonzero if this is the special handling, at end of compilation,
1578 to define things that have had only tentative definitions.
1579 DONT_OUTPUT_DATA if nonzero means don't actually output the
1580 initial value (that will be done by the caller). */
1581
1582 void
1583 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
1584 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
1585 {
1586 const char *name;
1587 unsigned int align;
1588 int reloc = 0;
1589 rtx decl_rtl;
1590
1591 if (lang_hooks.decls.prepare_assemble_variable)
1592 lang_hooks.decls.prepare_assemble_variable (decl);
1593
1594 last_assemble_variable_decl = 0;
1595
1596 /* Normally no need to say anything here for external references,
1597 since assemble_external is called by the language-specific code
1598 when a declaration is first seen. */
1599
1600 if (DECL_EXTERNAL (decl))
1601 return;
1602
1603 /* Output no assembler code for a function declaration.
1604 Only definitions of functions output anything. */
1605
1606 if (TREE_CODE (decl) == FUNCTION_DECL)
1607 return;
1608
1609 /* Do nothing for global register variables. */
1610 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
1611 {
1612 TREE_ASM_WRITTEN (decl) = 1;
1613 return;
1614 }
1615
1616 /* If type was incomplete when the variable was declared,
1617 see if it is complete now. */
1618
1619 if (DECL_SIZE (decl) == 0)
1620 layout_decl (decl, 0);
1621
1622 /* Still incomplete => don't allocate it; treat the tentative defn
1623 (which is what it must have been) as an `extern' reference. */
1624
1625 if (!dont_output_data && DECL_SIZE (decl) == 0)
1626 {
1627 error ("%Jstorage size of %qD isn%'t known", decl, decl);
1628 TREE_ASM_WRITTEN (decl) = 1;
1629 return;
1630 }
1631
1632 /* The first declaration of a variable that comes through this function
1633 decides whether it is global (in C, has external linkage)
1634 or local (in C, has internal linkage). So do nothing more
1635 if this function has already run. */
1636
1637 if (TREE_ASM_WRITTEN (decl))
1638 return;
1639
1640 /* Make sure targetm.encode_section_info is invoked before we set
1641 ASM_WRITTEN. */
1642 decl_rtl = DECL_RTL (decl);
1643
1644 TREE_ASM_WRITTEN (decl) = 1;
1645
1646 /* Do no output if -fsyntax-only. */
1647 if (flag_syntax_only)
1648 return;
1649
1650 app_disable ();
1651
1652 if (! dont_output_data
1653 && ! host_integerp (DECL_SIZE_UNIT (decl), 1))
1654 {
1655 error ("%Jsize of variable %qD is too large", decl, decl);
1656 return;
1657 }
1658
1659 name = XSTR (XEXP (decl_rtl, 0), 0);
1660 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
1661 notice_global_symbol (decl);
1662
1663 /* Compute the alignment of this data. */
1664
1665 align = DECL_ALIGN (decl);
1666
1667 /* In the case for initialing an array whose length isn't specified,
1668 where we have not yet been able to do the layout,
1669 figure out the proper alignment now. */
1670 if (dont_output_data && DECL_SIZE (decl) == 0
1671 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
1672 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
1673
1674 /* Some object file formats have a maximum alignment which they support.
1675 In particular, a.out format supports a maximum alignment of 4. */
1676 if (align > MAX_OFILE_ALIGNMENT)
1677 {
1678 warning ("%Jalignment of %qD is greater than maximum object "
1679 "file alignment. Using %d", decl, decl,
1680 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
1681 align = MAX_OFILE_ALIGNMENT;
1682 }
1683
1684 /* On some machines, it is good to increase alignment sometimes. */
1685 if (! DECL_USER_ALIGN (decl))
1686 {
1687 #ifdef DATA_ALIGNMENT
1688 align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1689 #endif
1690 #ifdef CONSTANT_ALIGNMENT
1691 if (DECL_INITIAL (decl) != 0 && DECL_INITIAL (decl) != error_mark_node)
1692 align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
1693 #endif
1694 }
1695
1696 /* Reset the alignment in case we have made it tighter, so we can benefit
1697 from it in get_pointer_alignment. */
1698 DECL_ALIGN (decl) = align;
1699 set_mem_align (decl_rtl, align);
1700
1701 if (TREE_PUBLIC (decl))
1702 maybe_assemble_visibility (decl);
1703
1704 if (DECL_PRESERVE_P (decl))
1705 targetm.asm_out.mark_decl_preserved (name);
1706
1707 /* Handle uninitialized definitions. */
1708
1709 /* If the decl has been given an explicit section name, then it
1710 isn't common, and shouldn't be handled as such. */
1711 if (DECL_SECTION_NAME (decl) || dont_output_data)
1712 ;
1713 /* We don't implement common thread-local data at present. */
1714 else if (DECL_THREAD_LOCAL (decl))
1715 {
1716 if (DECL_COMMON (decl))
1717 sorry ("thread-local COMMON data not implemented");
1718 }
1719 else if (DECL_INITIAL (decl) == 0
1720 || DECL_INITIAL (decl) == error_mark_node
1721 || (flag_zero_initialized_in_bss
1722 /* Leave constant zeroes in .rodata so they can be shared. */
1723 && !TREE_READONLY (decl)
1724 && initializer_zerop (DECL_INITIAL (decl))))
1725 {
1726 unsigned HOST_WIDE_INT size = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
1727 unsigned HOST_WIDE_INT rounded = size;
1728
1729 /* Don't allocate zero bytes of common,
1730 since that means "undefined external" in the linker. */
1731 if (size == 0)
1732 rounded = 1;
1733
1734 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1735 so that each uninitialized object starts on such a boundary. */
1736 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
1737 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1738 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1739
1740 #if !defined(ASM_OUTPUT_ALIGNED_COMMON) && !defined(ASM_OUTPUT_ALIGNED_DECL_COMMON) && !defined(ASM_OUTPUT_ALIGNED_BSS)
1741 if ((unsigned HOST_WIDE_INT) DECL_ALIGN_UNIT (decl) > rounded)
1742 warning ("%Jrequested alignment for %qD is greater than "
1743 "implemented alignment of %d", decl, decl, rounded);
1744 #endif
1745
1746 /* If the target cannot output uninitialized but not common global data
1747 in .bss, then we have to use .data, so fall through. */
1748 if (asm_emit_uninitialised (decl, name, size, rounded))
1749 return;
1750 }
1751
1752 /* Handle initialized definitions.
1753 Also handle uninitialized global definitions if -fno-common and the
1754 target doesn't support ASM_OUTPUT_BSS. */
1755
1756 /* First make the assembler name(s) global if appropriate. */
1757 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
1758 globalize_decl (decl);
1759
1760 /* Output any data that we will need to use the address of. */
1761 if (DECL_INITIAL (decl) == error_mark_node)
1762 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1763 else if (DECL_INITIAL (decl))
1764 {
1765 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1766 output_addressed_constants (DECL_INITIAL (decl));
1767 }
1768
1769 /* Switch to the appropriate section. */
1770 resolve_unique_section (decl, reloc, flag_data_sections);
1771 variable_section (decl, reloc);
1772
1773 /* dbxout.c needs to know this. */
1774 if (in_text_section () || in_unlikely_text_section ())
1775 DECL_IN_TEXT_SECTION (decl) = 1;
1776
1777 /* Output the alignment of this data. */
1778 if (align > BITS_PER_UNIT)
1779 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (DECL_ALIGN_UNIT (decl)));
1780
1781 /* Do any machine/system dependent processing of the object. */
1782 #ifdef ASM_DECLARE_OBJECT_NAME
1783 last_assemble_variable_decl = decl;
1784 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
1785 #else
1786 /* Standard thing is just output label for the object. */
1787 ASM_OUTPUT_LABEL (asm_out_file, name);
1788 #endif /* ASM_DECLARE_OBJECT_NAME */
1789
1790 if (!dont_output_data)
1791 {
1792 if (DECL_INITIAL (decl)
1793 && DECL_INITIAL (decl) != error_mark_node
1794 && !initializer_zerop (DECL_INITIAL (decl)))
1795 /* Output the actual data. */
1796 output_constant (DECL_INITIAL (decl),
1797 tree_low_cst (DECL_SIZE_UNIT (decl), 1),
1798 align);
1799 else
1800 /* Leave space for it. */
1801 assemble_zeros (tree_low_cst (DECL_SIZE_UNIT (decl), 1));
1802 }
1803 }
1804
1805 /* Return 1 if type TYPE contains any pointers. */
1806
1807 static int
1808 contains_pointers_p (tree type)
1809 {
1810 switch (TREE_CODE (type))
1811 {
1812 case POINTER_TYPE:
1813 case REFERENCE_TYPE:
1814 /* I'm not sure whether OFFSET_TYPE needs this treatment,
1815 so I'll play safe and return 1. */
1816 case OFFSET_TYPE:
1817 return 1;
1818
1819 case RECORD_TYPE:
1820 case UNION_TYPE:
1821 case QUAL_UNION_TYPE:
1822 {
1823 tree fields;
1824 /* For a type that has fields, see if the fields have pointers. */
1825 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
1826 if (TREE_CODE (fields) == FIELD_DECL
1827 && contains_pointers_p (TREE_TYPE (fields)))
1828 return 1;
1829 return 0;
1830 }
1831
1832 case ARRAY_TYPE:
1833 /* An array type contains pointers if its element type does. */
1834 return contains_pointers_p (TREE_TYPE (type));
1835
1836 default:
1837 return 0;
1838 }
1839 }
1840
1841 /* In unit-at-a-time mode, we delay assemble_external processing until
1842 the compilation unit is finalized. This is the best we can do for
1843 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
1844 it all the way to final. See PR 17982 for further discussion. */
1845 static GTY(()) tree pending_assemble_externals;
1846
1847 #ifdef ASM_OUTPUT_EXTERNAL
1848 /* True if DECL is a function decl for which no out-of-line copy exists.
1849 It is assumed that DECL's assembler name has been set. */
1850
1851 static bool
1852 incorporeal_function_p (tree decl)
1853 {
1854 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
1855 {
1856 const char *name;
1857
1858 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
1859 && DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA)
1860 return true;
1861
1862 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
1863 if (strncmp (name, "__builtin_", strlen ("__builtin_")) == 0)
1864 return true;
1865 }
1866 return false;
1867 }
1868
1869 /* Actually do the tests to determine if this is necessary, and invoke
1870 ASM_OUTPUT_EXTERNAL. */
1871 static void
1872 assemble_external_real (tree decl)
1873 {
1874 rtx rtl = DECL_RTL (decl);
1875
1876 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
1877 && !SYMBOL_REF_USED (XEXP (rtl, 0))
1878 && !incorporeal_function_p (decl))
1879 {
1880 /* Some systems do require some output. */
1881 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
1882 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
1883 }
1884 }
1885 #endif
1886
1887 void
1888 process_pending_assemble_externals (void)
1889 {
1890 #ifdef ASM_OUTPUT_EXTERNAL
1891 tree list;
1892 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
1893 assemble_external_real (TREE_VALUE (list));
1894
1895 pending_assemble_externals = 0;
1896 #endif
1897 }
1898
1899 /* Output something to declare an external symbol to the assembler.
1900 (Most assemblers don't need this, so we normally output nothing.)
1901 Do nothing if DECL is not external. */
1902
1903 void
1904 assemble_external (tree decl ATTRIBUTE_UNUSED)
1905 {
1906 /* Because most platforms do not define ASM_OUTPUT_EXTERNAL, the
1907 main body of this code is only rarely exercised. To provide some
1908 testing, on all platforms, we make sure that the ASM_OUT_FILE is
1909 open. If it's not, we should not be calling this function. */
1910 gcc_assert (asm_out_file);
1911
1912 #ifdef ASM_OUTPUT_EXTERNAL
1913 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
1914 return;
1915
1916 if (flag_unit_at_a_time)
1917 pending_assemble_externals = tree_cons (0, decl,
1918 pending_assemble_externals);
1919 else
1920 assemble_external_real (decl);
1921 #endif
1922 }
1923
1924 /* Similar, for calling a library function FUN. */
1925
1926 void
1927 assemble_external_libcall (rtx fun)
1928 {
1929 /* Declare library function name external when first used, if nec. */
1930 if (! SYMBOL_REF_USED (fun))
1931 {
1932 SYMBOL_REF_USED (fun) = 1;
1933 targetm.asm_out.external_libcall (fun);
1934 }
1935 }
1936
1937 /* Assemble a label named NAME. */
1938
1939 void
1940 assemble_label (const char *name)
1941 {
1942 ASM_OUTPUT_LABEL (asm_out_file, name);
1943 }
1944
1945 /* Set the symbol_referenced flag for ID. */
1946 void
1947 mark_referenced (tree id)
1948 {
1949 TREE_SYMBOL_REFERENCED (id) = 1;
1950 }
1951
1952 /* Set the symbol_referenced flag for DECL and notify callgraph. */
1953 void
1954 mark_decl_referenced (tree decl)
1955 {
1956 if (TREE_CODE (decl) == FUNCTION_DECL)
1957 {
1958 /* Extern inline functions don't become needed when referenced. */
1959 if (!DECL_EXTERNAL (decl))
1960 cgraph_mark_needed_node (cgraph_node (decl));
1961 }
1962 else if (TREE_CODE (decl) == VAR_DECL)
1963 {
1964 struct cgraph_varpool_node *node = cgraph_varpool_node (decl);
1965 cgraph_varpool_mark_needed_node (node);
1966 /* C++ frontend use mark_decl_references to force COMDAT variables
1967 to be output that might appear dead otherwise. */
1968 node->force_output = true;
1969 }
1970 /* else do nothing - we can get various sorts of CST nodes here,
1971 which do not need to be marked. */
1972 }
1973
1974 /* Output to FILE (an assembly file) a reference to NAME. If NAME
1975 starts with a *, the rest of NAME is output verbatim. Otherwise
1976 NAME is transformed in a target-specific way (usually by the
1977 addition of an underscore). */
1978
1979 void
1980 assemble_name_raw (FILE *file, const char *name)
1981 {
1982 if (name[0] == '*')
1983 fputs (&name[1], file);
1984 else
1985 ASM_OUTPUT_LABELREF (file, name);
1986 }
1987
1988 /* Like assemble_name_raw, but should be used when NAME might refer to
1989 an entity that is also represented as a tree (like a function or
1990 variable). If NAME does refer to such an entity, that entity will
1991 be marked as referenced. */
1992
1993 void
1994 assemble_name (FILE *file, const char *name)
1995 {
1996 const char *real_name;
1997 tree id;
1998
1999 real_name = targetm.strip_name_encoding (name);
2000
2001 id = maybe_get_identifier (real_name);
2002 if (id)
2003 mark_referenced (id);
2004
2005 assemble_name_raw (file, name);
2006 }
2007
2008 /* Allocate SIZE bytes writable static space with a gensym name
2009 and return an RTX to refer to its address. */
2010
2011 rtx
2012 assemble_static_space (unsigned HOST_WIDE_INT size)
2013 {
2014 char name[12];
2015 const char *namestring;
2016 rtx x;
2017
2018 #if 0
2019 if (flag_shared_data)
2020 data_section ();
2021 #endif
2022
2023 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2024 ++const_labelno;
2025 namestring = ggc_strdup (name);
2026
2027 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2028 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2029
2030 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2031 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2032 BIGGEST_ALIGNMENT);
2033 #else
2034 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2035 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2036 #else
2037 {
2038 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2039 so that each uninitialized object starts on such a boundary. */
2040 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2041 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2042 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2043 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2044 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2045 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2046 }
2047 #endif
2048 #endif
2049 return x;
2050 }
2051
2052 /* Assemble the static constant template for function entry trampolines.
2053 This is done at most once per compilation.
2054 Returns an RTX for the address of the template. */
2055
2056 static GTY(()) rtx initial_trampoline;
2057
2058 #ifdef TRAMPOLINE_TEMPLATE
2059 rtx
2060 assemble_trampoline_template (void)
2061 {
2062 char label[256];
2063 const char *name;
2064 int align;
2065 rtx symbol;
2066
2067 if (initial_trampoline)
2068 return initial_trampoline;
2069
2070 /* By default, put trampoline templates in read-only data section. */
2071
2072 #ifdef TRAMPOLINE_SECTION
2073 TRAMPOLINE_SECTION ();
2074 #else
2075 readonly_data_section ();
2076 #endif
2077
2078 /* Write the assembler code to define one. */
2079 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2080 if (align > 0)
2081 {
2082 ASM_OUTPUT_ALIGN (asm_out_file, align);
2083 }
2084
2085 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2086 TRAMPOLINE_TEMPLATE (asm_out_file);
2087
2088 /* Record the rtl to refer to it. */
2089 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2090 name = ggc_strdup (label);
2091 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2092 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2093
2094 initial_trampoline = gen_rtx_MEM (BLKmode, symbol);
2095 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2096
2097 return initial_trampoline;
2098 }
2099 #endif
2100 \f
2101 /* A and B are either alignments or offsets. Return the minimum alignment
2102 that may be assumed after adding the two together. */
2103
2104 static inline unsigned
2105 min_align (unsigned int a, unsigned int b)
2106 {
2107 return (a | b) & -(a | b);
2108 }
2109
2110 /* Return the assembler directive for creating a given kind of integer
2111 object. SIZE is the number of bytes in the object and ALIGNED_P
2112 indicates whether it is known to be aligned. Return NULL if the
2113 assembly dialect has no such directive.
2114
2115 The returned string should be printed at the start of a new line and
2116 be followed immediately by the object's initial value. */
2117
2118 const char *
2119 integer_asm_op (int size, int aligned_p)
2120 {
2121 struct asm_int_op *ops;
2122
2123 if (aligned_p)
2124 ops = &targetm.asm_out.aligned_op;
2125 else
2126 ops = &targetm.asm_out.unaligned_op;
2127
2128 switch (size)
2129 {
2130 case 1:
2131 return targetm.asm_out.byte_op;
2132 case 2:
2133 return ops->hi;
2134 case 4:
2135 return ops->si;
2136 case 8:
2137 return ops->di;
2138 case 16:
2139 return ops->ti;
2140 default:
2141 return NULL;
2142 }
2143 }
2144
2145 /* Use directive OP to assemble an integer object X. Print OP at the
2146 start of the line, followed immediately by the value of X. */
2147
2148 void
2149 assemble_integer_with_op (const char *op, rtx x)
2150 {
2151 fputs (op, asm_out_file);
2152 output_addr_const (asm_out_file, x);
2153 fputc ('\n', asm_out_file);
2154 }
2155
2156 /* The default implementation of the asm_out.integer target hook. */
2157
2158 bool
2159 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2160 unsigned int size ATTRIBUTE_UNUSED,
2161 int aligned_p ATTRIBUTE_UNUSED)
2162 {
2163 const char *op = integer_asm_op (size, aligned_p);
2164 /* Avoid GAS bugs for large values. Specifically negative values whose
2165 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2166 if (size > UNITS_PER_WORD && size > POINTER_SIZE / BITS_PER_UNIT)
2167 return false;
2168 return op && (assemble_integer_with_op (op, x), true);
2169 }
2170
2171 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2172 the alignment of the integer in bits. Return 1 if we were able to output
2173 the constant, otherwise 0. We must be able to output the constant,
2174 if FORCE is nonzero. */
2175
2176 bool
2177 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2178 {
2179 int aligned_p;
2180
2181 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2182
2183 /* See if the target hook can handle this kind of object. */
2184 if (targetm.asm_out.integer (x, size, aligned_p))
2185 return true;
2186
2187 /* If the object is a multi-byte one, try splitting it up. Split
2188 it into words it if is multi-word, otherwise split it into bytes. */
2189 if (size > 1)
2190 {
2191 enum machine_mode omode, imode;
2192 unsigned int subalign;
2193 unsigned int subsize, i;
2194
2195 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2196 subalign = MIN (align, subsize * BITS_PER_UNIT);
2197 omode = mode_for_size (subsize * BITS_PER_UNIT, MODE_INT, 0);
2198 imode = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
2199
2200 for (i = 0; i < size; i += subsize)
2201 {
2202 rtx partial = simplify_subreg (omode, x, imode, i);
2203 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2204 break;
2205 }
2206 if (i == size)
2207 return true;
2208
2209 /* If we've printed some of it, but not all of it, there's no going
2210 back now. */
2211 gcc_assert (!i);
2212 }
2213
2214 gcc_assert (!force);
2215
2216 return false;
2217 }
2218 \f
2219 void
2220 assemble_real (REAL_VALUE_TYPE d, enum machine_mode mode, unsigned int align)
2221 {
2222 long data[4];
2223 int i;
2224 int bitsize, nelts, nunits, units_per;
2225
2226 /* This is hairy. We have a quantity of known size. real_to_target
2227 will put it into an array of *host* longs, 32 bits per element
2228 (even if long is more than 32 bits). We need to determine the
2229 number of array elements that are occupied (nelts) and the number
2230 of *target* min-addressable units that will be occupied in the
2231 object file (nunits). We cannot assume that 32 divides the
2232 mode's bitsize (size * BITS_PER_UNIT) evenly.
2233
2234 size * BITS_PER_UNIT is used here to make sure that padding bits
2235 (which might appear at either end of the value; real_to_target
2236 will include the padding bits in its output array) are included. */
2237
2238 nunits = GET_MODE_SIZE (mode);
2239 bitsize = nunits * BITS_PER_UNIT;
2240 nelts = CEIL (bitsize, 32);
2241 units_per = 32 / BITS_PER_UNIT;
2242
2243 real_to_target (data, &d, mode);
2244
2245 /* Put out the first word with the specified alignment. */
2246 assemble_integer (GEN_INT (data[0]), MIN (nunits, units_per), align, 1);
2247 nunits -= units_per;
2248
2249 /* Subsequent words need only 32-bit alignment. */
2250 align = min_align (align, 32);
2251
2252 for (i = 1; i < nelts; i++)
2253 {
2254 assemble_integer (GEN_INT (data[i]), MIN (nunits, units_per), align, 1);
2255 nunits -= units_per;
2256 }
2257 }
2258 \f
2259 /* Given an expression EXP with a constant value,
2260 reduce it to the sum of an assembler symbol and an integer.
2261 Store them both in the structure *VALUE.
2262 EXP must be reduceable. */
2263
2264 struct addr_const GTY(())
2265 {
2266 rtx base;
2267 HOST_WIDE_INT offset;
2268 };
2269
2270 static void
2271 decode_addr_const (tree exp, struct addr_const *value)
2272 {
2273 tree target = TREE_OPERAND (exp, 0);
2274 int offset = 0;
2275 rtx x;
2276
2277 while (1)
2278 {
2279 if (TREE_CODE (target) == COMPONENT_REF
2280 && host_integerp (byte_position (TREE_OPERAND (target, 1)), 0))
2281
2282 {
2283 offset += int_byte_position (TREE_OPERAND (target, 1));
2284 target = TREE_OPERAND (target, 0);
2285 }
2286 else if (TREE_CODE (target) == ARRAY_REF
2287 || TREE_CODE (target) == ARRAY_RANGE_REF)
2288 {
2289 offset += (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (target)), 1)
2290 * tree_low_cst (TREE_OPERAND (target, 1), 0));
2291 target = TREE_OPERAND (target, 0);
2292 }
2293 else
2294 break;
2295 }
2296
2297 switch (TREE_CODE (target))
2298 {
2299 case VAR_DECL:
2300 case FUNCTION_DECL:
2301 x = DECL_RTL (target);
2302 break;
2303
2304 case LABEL_DECL:
2305 x = gen_rtx_MEM (FUNCTION_MODE,
2306 gen_rtx_LABEL_REF (VOIDmode, force_label_rtx (target)));
2307 break;
2308
2309 case REAL_CST:
2310 case STRING_CST:
2311 case COMPLEX_CST:
2312 case CONSTRUCTOR:
2313 case INTEGER_CST:
2314 x = output_constant_def (target, 1);
2315 break;
2316
2317 default:
2318 gcc_unreachable ();
2319 }
2320
2321 gcc_assert (MEM_P (x));
2322 x = XEXP (x, 0);
2323
2324 value->base = x;
2325 value->offset = offset;
2326 }
2327 \f
2328 /* Uniquize all constants that appear in memory.
2329 Each constant in memory thus far output is recorded
2330 in `const_desc_table'. */
2331
2332 struct constant_descriptor_tree GTY(())
2333 {
2334 /* A MEM for the constant. */
2335 rtx rtl;
2336
2337 /* The value of the constant. */
2338 tree value;
2339 };
2340
2341 static GTY((param_is (struct constant_descriptor_tree)))
2342 htab_t const_desc_htab;
2343
2344 static struct constant_descriptor_tree * build_constant_desc (tree);
2345 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2346
2347 /* Compute a hash code for a constant expression. */
2348
2349 static hashval_t
2350 const_desc_hash (const void *ptr)
2351 {
2352 return const_hash_1 (((struct constant_descriptor_tree *)ptr)->value);
2353 }
2354
2355 static hashval_t
2356 const_hash_1 (const tree exp)
2357 {
2358 const char *p;
2359 hashval_t hi;
2360 int len, i;
2361 enum tree_code code = TREE_CODE (exp);
2362
2363 /* Either set P and LEN to the address and len of something to hash and
2364 exit the switch or return a value. */
2365
2366 switch (code)
2367 {
2368 case INTEGER_CST:
2369 p = (char *) &TREE_INT_CST (exp);
2370 len = sizeof TREE_INT_CST (exp);
2371 break;
2372
2373 case REAL_CST:
2374 return real_hash (TREE_REAL_CST_PTR (exp));
2375
2376 case STRING_CST:
2377 p = TREE_STRING_POINTER (exp);
2378 len = TREE_STRING_LENGTH (exp);
2379 break;
2380
2381 case COMPLEX_CST:
2382 return (const_hash_1 (TREE_REALPART (exp)) * 5
2383 + const_hash_1 (TREE_IMAGPART (exp)));
2384
2385 case CONSTRUCTOR:
2386 {
2387 tree link;
2388
2389 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2390
2391 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link))
2392 if (TREE_VALUE (link))
2393 hi = hi * 603 + const_hash_1 (TREE_VALUE (link));
2394
2395 return hi;
2396 }
2397
2398 case ADDR_EXPR:
2399 case FDESC_EXPR:
2400 {
2401 struct addr_const value;
2402
2403 decode_addr_const (exp, &value);
2404 switch (GET_CODE (value.base))
2405 {
2406 case SYMBOL_REF:
2407 /* Don't hash the address of the SYMBOL_REF;
2408 only use the offset and the symbol name. */
2409 hi = value.offset;
2410 p = XSTR (value.base, 0);
2411 for (i = 0; p[i] != 0; i++)
2412 hi = ((hi * 613) + (unsigned) (p[i]));
2413 break;
2414
2415 case LABEL_REF:
2416 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13;
2417 break;
2418
2419 default:
2420 gcc_unreachable ();
2421 }
2422 }
2423 return hi;
2424
2425 case PLUS_EXPR:
2426 case MINUS_EXPR:
2427 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2428 + const_hash_1 (TREE_OPERAND (exp, 1)));
2429
2430 case NOP_EXPR:
2431 case CONVERT_EXPR:
2432 case NON_LVALUE_EXPR:
2433 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
2434
2435 default:
2436 /* A language specific constant. Just hash the code. */
2437 return code;
2438 }
2439
2440 /* Compute hashing function. */
2441 hi = len;
2442 for (i = 0; i < len; i++)
2443 hi = ((hi * 613) + (unsigned) (p[i]));
2444
2445 return hi;
2446 }
2447
2448 /* Wrapper of compare_constant, for the htab interface. */
2449 static int
2450 const_desc_eq (const void *p1, const void *p2)
2451 {
2452 return compare_constant (((struct constant_descriptor_tree *)p1)->value,
2453 ((struct constant_descriptor_tree *)p2)->value);
2454 }
2455
2456 /* Compare t1 and t2, and return 1 only if they are known to result in
2457 the same bit pattern on output. */
2458
2459 static int
2460 compare_constant (const tree t1, const tree t2)
2461 {
2462 enum tree_code typecode;
2463
2464 if (t1 == NULL_TREE)
2465 return t2 == NULL_TREE;
2466 if (t2 == NULL_TREE)
2467 return 0;
2468
2469 if (TREE_CODE (t1) != TREE_CODE (t2))
2470 return 0;
2471
2472 switch (TREE_CODE (t1))
2473 {
2474 case INTEGER_CST:
2475 /* Integer constants are the same only if the same width of type. */
2476 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2477 return 0;
2478 return tree_int_cst_equal (t1, t2);
2479
2480 case REAL_CST:
2481 /* Real constants are the same only if the same width of type. */
2482 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2483 return 0;
2484
2485 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
2486
2487 case STRING_CST:
2488 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2489 return 0;
2490
2491 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
2492 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
2493 TREE_STRING_LENGTH (t1)));
2494
2495 case COMPLEX_CST:
2496 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
2497 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
2498
2499 case CONSTRUCTOR:
2500 {
2501 tree l1, l2;
2502
2503 typecode = TREE_CODE (TREE_TYPE (t1));
2504 if (typecode != TREE_CODE (TREE_TYPE (t2)))
2505 return 0;
2506
2507 if (typecode == ARRAY_TYPE)
2508 {
2509 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
2510 /* For arrays, check that the sizes all match. */
2511 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
2512 || size_1 == -1
2513 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
2514 return 0;
2515 }
2516 else
2517 {
2518 /* For record and union constructors, require exact type
2519 equality. */
2520 if (TREE_TYPE (t1) != TREE_TYPE (t2))
2521 return 0;
2522 }
2523
2524 for (l1 = CONSTRUCTOR_ELTS (t1), l2 = CONSTRUCTOR_ELTS (t2);
2525 l1 && l2;
2526 l1 = TREE_CHAIN (l1), l2 = TREE_CHAIN (l2))
2527 {
2528 /* Check that each value is the same... */
2529 if (! compare_constant (TREE_VALUE (l1), TREE_VALUE (l2)))
2530 return 0;
2531 /* ... and that they apply to the same fields! */
2532 if (typecode == ARRAY_TYPE)
2533 {
2534 if (! compare_constant (TREE_PURPOSE (l1),
2535 TREE_PURPOSE (l2)))
2536 return 0;
2537 }
2538 else
2539 {
2540 if (TREE_PURPOSE (l1) != TREE_PURPOSE (l2))
2541 return 0;
2542 }
2543 }
2544
2545 return l1 == NULL_TREE && l2 == NULL_TREE;
2546 }
2547
2548 case ADDR_EXPR:
2549 case FDESC_EXPR:
2550 {
2551 struct addr_const value1, value2;
2552
2553 decode_addr_const (t1, &value1);
2554 decode_addr_const (t2, &value2);
2555 return (value1.offset == value2.offset
2556 && strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
2557 }
2558
2559 case PLUS_EXPR:
2560 case MINUS_EXPR:
2561 case RANGE_EXPR:
2562 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
2563 && compare_constant(TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
2564
2565 case NOP_EXPR:
2566 case CONVERT_EXPR:
2567 case NON_LVALUE_EXPR:
2568 case VIEW_CONVERT_EXPR:
2569 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
2570
2571 default:
2572 {
2573 tree nt1, nt2;
2574 nt1 = lang_hooks.expand_constant (t1);
2575 nt2 = lang_hooks.expand_constant (t2);
2576 if (nt1 != t1 || nt2 != t2)
2577 return compare_constant (nt1, nt2);
2578 else
2579 return 0;
2580 }
2581 }
2582
2583 gcc_unreachable ();
2584 }
2585 \f
2586 /* Make a copy of the whole tree structure for a constant. This
2587 handles the same types of nodes that compare_constant handles. */
2588
2589 static tree
2590 copy_constant (tree exp)
2591 {
2592 switch (TREE_CODE (exp))
2593 {
2594 case ADDR_EXPR:
2595 /* For ADDR_EXPR, we do not want to copy the decl whose address
2596 is requested. We do want to copy constants though. */
2597 if (CONSTANT_CLASS_P (TREE_OPERAND (exp, 0)))
2598 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
2599 copy_constant (TREE_OPERAND (exp, 0)));
2600 else
2601 return copy_node (exp);
2602
2603 case INTEGER_CST:
2604 case REAL_CST:
2605 case STRING_CST:
2606 return copy_node (exp);
2607
2608 case COMPLEX_CST:
2609 return build_complex (TREE_TYPE (exp),
2610 copy_constant (TREE_REALPART (exp)),
2611 copy_constant (TREE_IMAGPART (exp)));
2612
2613 case PLUS_EXPR:
2614 case MINUS_EXPR:
2615 return build2 (TREE_CODE (exp), TREE_TYPE (exp),
2616 copy_constant (TREE_OPERAND (exp, 0)),
2617 copy_constant (TREE_OPERAND (exp, 1)));
2618
2619 case NOP_EXPR:
2620 case CONVERT_EXPR:
2621 case NON_LVALUE_EXPR:
2622 case VIEW_CONVERT_EXPR:
2623 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
2624 copy_constant (TREE_OPERAND (exp, 0)));
2625
2626 case CONSTRUCTOR:
2627 {
2628 tree copy = copy_node (exp);
2629 tree list = copy_list (CONSTRUCTOR_ELTS (exp));
2630 tree tail;
2631
2632 CONSTRUCTOR_ELTS (copy) = list;
2633 for (tail = list; tail; tail = TREE_CHAIN (tail))
2634 TREE_VALUE (tail) = copy_constant (TREE_VALUE (tail));
2635
2636 return copy;
2637 }
2638
2639 default:
2640 {
2641 tree t = lang_hooks.expand_constant (exp);
2642
2643 gcc_assert (t == exp);
2644 return copy_constant (t);
2645 }
2646 }
2647 }
2648 \f
2649 /* Subroutine of output_constant_def:
2650 No constant equal to EXP is known to have been output.
2651 Make a constant descriptor to enter EXP in the hash table.
2652 Assign the label number and construct RTL to refer to the
2653 constant's location in memory.
2654 Caller is responsible for updating the hash table. */
2655
2656 static struct constant_descriptor_tree *
2657 build_constant_desc (tree exp)
2658 {
2659 rtx symbol;
2660 rtx rtl;
2661 char label[256];
2662 int labelno;
2663 struct constant_descriptor_tree *desc;
2664
2665 desc = ggc_alloc (sizeof (*desc));
2666 desc->value = copy_constant (exp);
2667
2668 /* Propagate marked-ness to copied constant. */
2669 if (flag_mudflap && mf_marked_p (exp))
2670 mf_mark (desc->value);
2671
2672 /* Create a string containing the label name, in LABEL. */
2673 labelno = const_labelno++;
2674 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
2675
2676 /* We have a symbol name; construct the SYMBOL_REF and the MEM. */
2677 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
2678 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2679 SYMBOL_REF_DECL (symbol) = desc->value;
2680 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
2681
2682 rtl = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)), symbol);
2683 set_mem_attributes (rtl, exp, 1);
2684 set_mem_alias_set (rtl, 0);
2685 set_mem_alias_set (rtl, const_alias_set);
2686
2687 /* Set flags or add text to the name to record information, such as
2688 that it is a local symbol. If the name is changed, the macro
2689 ASM_OUTPUT_LABELREF will have to know how to strip this
2690 information. This call might invalidate our local variable
2691 SYMBOL; we can't use it afterward. */
2692
2693 targetm.encode_section_info (exp, rtl, true);
2694
2695 desc->rtl = rtl;
2696
2697 return desc;
2698 }
2699
2700 /* Return an rtx representing a reference to constant data in memory
2701 for the constant expression EXP.
2702
2703 If assembler code for such a constant has already been output,
2704 return an rtx to refer to it.
2705 Otherwise, output such a constant in memory
2706 and generate an rtx for it.
2707
2708 If DEFER is nonzero, this constant can be deferred and output only
2709 if referenced in the function after all optimizations.
2710
2711 `const_desc_table' records which constants already have label strings. */
2712
2713 rtx
2714 output_constant_def (tree exp, int defer)
2715 {
2716 struct constant_descriptor_tree *desc;
2717 struct constant_descriptor_tree key;
2718 void **loc;
2719
2720 /* Look up EXP in the table of constant descriptors. If we didn't find
2721 it, create a new one. */
2722 key.value = exp;
2723 loc = htab_find_slot (const_desc_htab, &key, INSERT);
2724
2725 desc = *loc;
2726 if (desc == 0)
2727 {
2728 desc = build_constant_desc (exp);
2729 *loc = desc;
2730 }
2731
2732 maybe_output_constant_def_contents (desc, defer);
2733 return desc->rtl;
2734 }
2735
2736 /* Subroutine of output_constant_def: Decide whether or not we need to
2737 output the constant DESC now, and if so, do it. */
2738 static void
2739 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
2740 int defer)
2741 {
2742 rtx symbol = XEXP (desc->rtl, 0);
2743 tree exp = desc->value;
2744
2745 if (flag_syntax_only)
2746 return;
2747
2748 if (TREE_ASM_WRITTEN (exp))
2749 /* Already output; don't do it again. */
2750 return;
2751
2752 /* We can always defer constants as long as the context allows
2753 doing so. */
2754 if (defer)
2755 {
2756 /* Increment n_deferred_constants if it exists. It needs to be at
2757 least as large as the number of constants actually referred to
2758 by the function. If it's too small we'll stop looking too early
2759 and fail to emit constants; if it's too large we'll only look
2760 through the entire function when we could have stopped earlier. */
2761 if (cfun)
2762 n_deferred_constants++;
2763 return;
2764 }
2765
2766 output_constant_def_contents (symbol);
2767 }
2768
2769 /* We must output the constant data referred to by SYMBOL; do so. */
2770
2771 static void
2772 output_constant_def_contents (rtx symbol)
2773 {
2774 tree exp = SYMBOL_REF_DECL (symbol);
2775 const char *label = XSTR (symbol, 0);
2776 HOST_WIDE_INT size;
2777
2778 /* Make sure any other constants whose addresses appear in EXP
2779 are assigned label numbers. */
2780 int reloc = compute_reloc_for_constant (exp);
2781
2782 /* Align the location counter as required by EXP's data type. */
2783 unsigned int align = TYPE_ALIGN (TREE_TYPE (exp));
2784 #ifdef CONSTANT_ALIGNMENT
2785 align = CONSTANT_ALIGNMENT (exp, align);
2786 #endif
2787
2788 output_addressed_constants (exp);
2789
2790 /* We are no longer deferring this constant. */
2791 TREE_ASM_WRITTEN (exp) = 1;
2792
2793 if (IN_NAMED_SECTION (exp))
2794 named_section (exp, NULL, reloc);
2795 else
2796 targetm.asm_out.select_section (exp, reloc, align);
2797
2798 if (align > BITS_PER_UNIT)
2799 {
2800 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2801 }
2802
2803 size = int_size_in_bytes (TREE_TYPE (exp));
2804 if (TREE_CODE (exp) == STRING_CST)
2805 size = MAX (TREE_STRING_LENGTH (exp), size);
2806
2807 /* Do any machine/system dependent processing of the constant. */
2808 #ifdef ASM_DECLARE_CONSTANT_NAME
2809 ASM_DECLARE_CONSTANT_NAME (asm_out_file, label, exp, size);
2810 #else
2811 /* Standard thing is just output label for the constant. */
2812 ASM_OUTPUT_LABEL (asm_out_file, label);
2813 #endif /* ASM_DECLARE_CONSTANT_NAME */
2814
2815 /* Output the value of EXP. */
2816 output_constant (exp, size, align);
2817 if (flag_mudflap)
2818 mudflap_enqueue_constant (exp);
2819 }
2820
2821 /* Look up EXP in the table of constant descriptors. Return the rtl
2822 if it has been emitted, else null. */
2823
2824 rtx
2825 lookup_constant_def (tree exp)
2826 {
2827 struct constant_descriptor_tree *desc;
2828 struct constant_descriptor_tree key;
2829
2830 key.value = exp;
2831 desc = htab_find (const_desc_htab, &key);
2832
2833 return (desc ? desc->rtl : NULL_RTX);
2834 }
2835 \f
2836 /* Used in the hash tables to avoid outputting the same constant
2837 twice. Unlike 'struct constant_descriptor_tree', RTX constants
2838 are output once per function, not once per file. */
2839 /* ??? Only a few targets need per-function constant pools. Most
2840 can use one per-file pool. Should add a targetm bit to tell the
2841 difference. */
2842
2843 struct rtx_constant_pool GTY(())
2844 {
2845 /* Pointers to first and last constant in pool, as ordered by offset. */
2846 struct constant_descriptor_rtx *first;
2847 struct constant_descriptor_rtx *last;
2848
2849 /* Hash facility for making memory-constants from constant rtl-expressions.
2850 It is used on RISC machines where immediate integer arguments and
2851 constant addresses are restricted so that such constants must be stored
2852 in memory. */
2853 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_htab;
2854 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_sym_htab;
2855
2856 /* Current offset in constant pool (does not include any
2857 machine-specific header). */
2858 HOST_WIDE_INT offset;
2859 };
2860
2861 struct constant_descriptor_rtx GTY((chain_next ("%h.next")))
2862 {
2863 struct constant_descriptor_rtx *next;
2864 rtx mem;
2865 rtx sym;
2866 rtx constant;
2867 HOST_WIDE_INT offset;
2868 hashval_t hash;
2869 enum machine_mode mode;
2870 unsigned int align;
2871 int labelno;
2872 int mark;
2873 };
2874
2875 /* Hash and compare functions for const_rtx_htab. */
2876
2877 static hashval_t
2878 const_desc_rtx_hash (const void *ptr)
2879 {
2880 const struct constant_descriptor_rtx *desc = ptr;
2881 return desc->hash;
2882 }
2883
2884 static int
2885 const_desc_rtx_eq (const void *a, const void *b)
2886 {
2887 const struct constant_descriptor_rtx *x = a;
2888 const struct constant_descriptor_rtx *y = b;
2889
2890 if (x->mode != y->mode)
2891 return 0;
2892 return rtx_equal_p (x->constant, y->constant);
2893 }
2894
2895 /* Hash and compare functions for const_rtx_sym_htab. */
2896
2897 static hashval_t
2898 const_desc_rtx_sym_hash (const void *ptr)
2899 {
2900 const struct constant_descriptor_rtx *desc = ptr;
2901 return htab_hash_string (XSTR (desc->sym, 0));
2902 }
2903
2904 static int
2905 const_desc_rtx_sym_eq (const void *a, const void *b)
2906 {
2907 const struct constant_descriptor_rtx *x = a;
2908 const struct constant_descriptor_rtx *y = b;
2909 return XSTR (x->sym, 0) == XSTR (y->sym, 0);
2910 }
2911
2912 /* This is the worker function for const_rtx_hash, called via for_each_rtx. */
2913
2914 static int
2915 const_rtx_hash_1 (rtx *xp, void *data)
2916 {
2917 unsigned HOST_WIDE_INT hwi;
2918 enum machine_mode mode;
2919 enum rtx_code code;
2920 hashval_t h, *hp;
2921 rtx x;
2922
2923 x = *xp;
2924 code = GET_CODE (x);
2925 mode = GET_MODE (x);
2926 h = (hashval_t) code * 1048573 + mode;
2927
2928 switch (code)
2929 {
2930 case CONST_INT:
2931 hwi = INTVAL (x);
2932 fold_hwi:
2933 {
2934 const int shift = sizeof (hashval_t) * CHAR_BIT;
2935 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
2936 int i;
2937
2938 h ^= (hashval_t) hwi;
2939 for (i = 1; i < n; ++i)
2940 {
2941 hwi >>= shift;
2942 h ^= (hashval_t) hwi;
2943 }
2944 }
2945 break;
2946
2947 case CONST_DOUBLE:
2948 if (mode == VOIDmode)
2949 {
2950 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
2951 goto fold_hwi;
2952 }
2953 else
2954 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
2955 break;
2956
2957 case CONST_VECTOR:
2958 {
2959 int i;
2960 for (i = XVECLEN (x, 0); i-- > 0; )
2961 h = h * 251 + const_rtx_hash_1 (&XVECEXP (x, 0, i), data);
2962 }
2963 break;
2964
2965 case SYMBOL_REF:
2966 h ^= htab_hash_string (XSTR (x, 0));
2967 break;
2968
2969 case LABEL_REF:
2970 h = h * 251 + CODE_LABEL_NUMBER (XEXP (x, 0));
2971 break;
2972
2973 case UNSPEC:
2974 case UNSPEC_VOLATILE:
2975 h = h * 251 + XINT (x, 1);
2976 break;
2977
2978 default:
2979 break;
2980 }
2981
2982 hp = data;
2983 *hp = *hp * 509 + h;
2984 return 0;
2985 }
2986
2987 /* Compute a hash value for X, which should be a constant. */
2988
2989 static hashval_t
2990 const_rtx_hash (rtx x)
2991 {
2992 hashval_t h = 0;
2993 for_each_rtx (&x, const_rtx_hash_1, &h);
2994 return h;
2995 }
2996
2997 \f
2998 /* Initialize constant pool hashing for a new function. */
2999
3000 void
3001 init_varasm_status (struct function *f)
3002 {
3003 struct varasm_status *p;
3004 struct rtx_constant_pool *pool;
3005
3006 p = ggc_alloc (sizeof (struct varasm_status));
3007 f->varasm = p;
3008
3009 pool = ggc_alloc (sizeof (struct rtx_constant_pool));
3010 p->pool = pool;
3011 p->deferred_constants = 0;
3012
3013 pool->const_rtx_htab = htab_create_ggc (31, const_desc_rtx_hash,
3014 const_desc_rtx_eq, NULL);
3015 pool->const_rtx_sym_htab = htab_create_ggc (31, const_desc_rtx_sym_hash,
3016 const_desc_rtx_sym_eq, NULL);
3017 pool->first = pool->last = NULL;
3018 pool->offset = 0;
3019 }
3020 \f
3021 /* Given a MINUS expression, simplify it if both sides
3022 include the same symbol. */
3023
3024 rtx
3025 simplify_subtraction (rtx x)
3026 {
3027 rtx r = simplify_rtx (x);
3028 return r ? r : x;
3029 }
3030 \f
3031 /* Given a constant rtx X, make (or find) a memory constant for its value
3032 and return a MEM rtx to refer to it in memory. */
3033
3034 rtx
3035 force_const_mem (enum machine_mode mode, rtx x)
3036 {
3037 struct constant_descriptor_rtx *desc, tmp;
3038 struct rtx_constant_pool *pool = cfun->varasm->pool;
3039 char label[256];
3040 rtx def, symbol;
3041 hashval_t hash;
3042 unsigned int align;
3043 void **slot;
3044
3045 /* If we're not allowed to drop X into the constant pool, don't. */
3046 if (targetm.cannot_force_const_mem (x))
3047 return NULL_RTX;
3048
3049 /* Lookup the value in the hashtable. */
3050 tmp.constant = x;
3051 tmp.mode = mode;
3052 hash = const_rtx_hash (x);
3053 slot = htab_find_slot_with_hash (pool->const_rtx_htab, &tmp, hash, INSERT);
3054 desc = *slot;
3055
3056 /* If the constant was already present, return its memory. */
3057 if (desc)
3058 return copy_rtx (desc->mem);
3059
3060 /* Otherwise, create a new descriptor. */
3061 desc = ggc_alloc (sizeof (*desc));
3062 *slot = desc;
3063
3064 /* Align the location counter as required by EXP's data type. */
3065 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3066 #ifdef CONSTANT_ALIGNMENT
3067 {
3068 tree type = lang_hooks.types.type_for_mode (mode, 0);
3069 if (type != NULL_TREE)
3070 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3071 }
3072 #endif
3073
3074 pool->offset += (align / BITS_PER_UNIT) - 1;
3075 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3076
3077 desc->next = NULL;
3078 desc->constant = tmp.constant;
3079 desc->offset = pool->offset;
3080 desc->hash = hash;
3081 desc->mode = mode;
3082 desc->align = align;
3083 desc->labelno = const_labelno;
3084 desc->mark = 0;
3085
3086 pool->offset += GET_MODE_SIZE (mode);
3087 if (pool->last)
3088 pool->last->next = desc;
3089 else
3090 pool->first = pool->last = desc;
3091 pool->last = desc;
3092
3093 /* Create a string containing the label name, in LABEL. */
3094 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3095 ++const_labelno;
3096
3097 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3098 the constants pool. */
3099 desc->sym = symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3100 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
3101 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3102 current_function_uses_const_pool = 1;
3103
3104 /* Insert the descriptor into the symbol cross-reference table too. */
3105 slot = htab_find_slot (pool->const_rtx_sym_htab, desc, INSERT);
3106 gcc_assert (!*slot);
3107 *slot = desc;
3108
3109 /* Construct the MEM. */
3110 desc->mem = def = gen_const_mem (mode, symbol);
3111 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3112 set_mem_align (def, align);
3113
3114 /* If we're dropping a label to the constant pool, make sure we
3115 don't delete it. */
3116 if (GET_CODE (x) == LABEL_REF)
3117 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3118
3119 return copy_rtx (def);
3120 }
3121 \f
3122 /* Given a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true, return a pointer to
3123 the corresponding constant_descriptor_rtx structure. */
3124
3125 static struct constant_descriptor_rtx *
3126 find_pool_constant (struct rtx_constant_pool *pool, rtx sym)
3127 {
3128 struct constant_descriptor_rtx tmp;
3129 tmp.sym = sym;
3130 return htab_find (pool->const_rtx_sym_htab, &tmp);
3131 }
3132
3133 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3134
3135 rtx
3136 get_pool_constant (rtx addr)
3137 {
3138 return find_pool_constant (cfun->varasm->pool, addr)->constant;
3139 }
3140
3141 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3142 and whether it has been output or not. */
3143
3144 rtx
3145 get_pool_constant_mark (rtx addr, bool *pmarked)
3146 {
3147 struct constant_descriptor_rtx *desc;
3148
3149 desc = find_pool_constant (cfun->varasm->pool, addr);
3150 *pmarked = (desc->mark != 0);
3151 return desc->constant;
3152 }
3153
3154 /* Likewise, but for the constant pool of a specific function. */
3155
3156 rtx
3157 get_pool_constant_for_function (struct function *f, rtx addr)
3158 {
3159 return find_pool_constant (f->varasm->pool, addr)->constant;
3160 }
3161
3162 /* Similar, return the mode. */
3163
3164 enum machine_mode
3165 get_pool_mode (rtx addr)
3166 {
3167 return find_pool_constant (cfun->varasm->pool, addr)->mode;
3168 }
3169
3170 /* Return the size of the constant pool. */
3171
3172 int
3173 get_pool_size (void)
3174 {
3175 return cfun->varasm->pool->offset;
3176 }
3177 \f
3178 /* Worker function for output_constant_pool_1. Emit assembly for X
3179 in MODE with known alignment ALIGN. */
3180
3181 static void
3182 output_constant_pool_2 (enum machine_mode mode, rtx x, unsigned int align)
3183 {
3184 switch (GET_MODE_CLASS (mode))
3185 {
3186 case MODE_FLOAT:
3187 {
3188 REAL_VALUE_TYPE r;
3189
3190 gcc_assert (GET_CODE (x) == CONST_DOUBLE);
3191 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3192 assemble_real (r, mode, align);
3193 break;
3194 }
3195
3196 case MODE_INT:
3197 case MODE_PARTIAL_INT:
3198 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3199 break;
3200
3201 case MODE_VECTOR_FLOAT:
3202 case MODE_VECTOR_INT:
3203 {
3204 int i, units;
3205 enum machine_mode submode = GET_MODE_INNER (mode);
3206 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3207
3208 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3209 units = CONST_VECTOR_NUNITS (x);
3210
3211 for (i = 0; i < units; i++)
3212 {
3213 rtx elt = CONST_VECTOR_ELT (x, i);
3214 output_constant_pool_2 (submode, elt, i ? subalign : align);
3215 }
3216 }
3217 break;
3218
3219 default:
3220 gcc_unreachable ();
3221 }
3222 }
3223
3224 /* Worker function for output_constant_pool. Emit POOL. */
3225
3226 static void
3227 output_constant_pool_1 (struct constant_descriptor_rtx *desc)
3228 {
3229 rtx x, tmp;
3230
3231 if (!desc->mark)
3232 return;
3233 x = desc->constant;
3234
3235 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3236 whose CODE_LABEL has been deleted. This can occur if a jump table
3237 is eliminated by optimization. If so, write a constant of zero
3238 instead. Note that this can also happen by turning the
3239 CODE_LABEL into a NOTE. */
3240 /* ??? This seems completely and utterly wrong. Certainly it's
3241 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3242 functioning even with INSN_DELETED_P and friends. */
3243
3244 tmp = x;
3245 switch (GET_CODE (x))
3246 {
3247 case CONST:
3248 if (GET_CODE (XEXP (x, 0)) != PLUS
3249 || GET_CODE (XEXP (XEXP (x, 0), 0)) != LABEL_REF)
3250 break;
3251 tmp = XEXP (XEXP (x, 0), 0);
3252 /* FALLTHRU */
3253
3254 case LABEL_REF:
3255 tmp = XEXP (x, 0);
3256 gcc_assert (!INSN_DELETED_P (tmp));
3257 gcc_assert (!NOTE_P (tmp)
3258 || NOTE_LINE_NUMBER (tmp) != NOTE_INSN_DELETED);
3259 break;
3260
3261 default:
3262 break;
3263 }
3264
3265 /* First switch to correct section. */
3266 targetm.asm_out.select_rtx_section (desc->mode, x, desc->align);
3267
3268 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3269 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3270 desc->align, desc->labelno, done);
3271 #endif
3272
3273 assemble_align (desc->align);
3274
3275 /* Output the label. */
3276 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3277
3278 /* Output the data. */
3279 output_constant_pool_2 (desc->mode, x, desc->align);
3280
3281 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3282 sections have proper size. */
3283 if (desc->align > GET_MODE_BITSIZE (desc->mode)
3284 && in_section == in_named
3285 && get_named_section_flags (in_named_name) & SECTION_MERGE)
3286 assemble_align (desc->align);
3287
3288 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3289 done:
3290 #endif
3291 return;
3292 }
3293
3294 /* Given a SYMBOL_REF CURRENT_RTX, mark it and all constants it refers
3295 to as used. Emit referenced deferred strings. This function can
3296 be used with for_each_rtx to mark all SYMBOL_REFs in an rtx. */
3297
3298 static int
3299 mark_constant (rtx *current_rtx, void *data)
3300 {
3301 struct rtx_constant_pool *pool = data;
3302 rtx x = *current_rtx;
3303
3304 if (x == NULL_RTX || GET_CODE (x) != SYMBOL_REF)
3305 return 0;
3306
3307 if (CONSTANT_POOL_ADDRESS_P (x))
3308 {
3309 struct constant_descriptor_rtx *desc = find_pool_constant (pool, x);
3310 if (desc->mark == 0)
3311 {
3312 desc->mark = 1;
3313 for_each_rtx (&desc->constant, mark_constant, pool);
3314 }
3315 }
3316 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3317 {
3318 tree exp = SYMBOL_REF_DECL (x);
3319 if (!TREE_ASM_WRITTEN (exp))
3320 {
3321 n_deferred_constants--;
3322 output_constant_def_contents (x);
3323 }
3324 }
3325
3326 return -1;
3327 }
3328
3329 /* Look through appropriate parts of INSN, marking all entries in the
3330 constant pool which are actually being used. Entries that are only
3331 referenced by other constants are also marked as used. Emit
3332 deferred strings that are used. */
3333
3334 static void
3335 mark_constants (struct rtx_constant_pool *pool, rtx insn)
3336 {
3337 if (!INSN_P (insn))
3338 return;
3339
3340 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3341 insns, not any notes that may be attached. We don't want to mark
3342 a constant just because it happens to appear in a REG_EQUIV note. */
3343 if (GET_CODE (PATTERN (insn)) == SEQUENCE)
3344 {
3345 rtx seq = PATTERN (insn);
3346 int i, n = XVECLEN (seq, 0);
3347 for (i = 0; i < n; ++i)
3348 {
3349 rtx subinsn = XVECEXP (seq, 0, i);
3350 if (INSN_P (subinsn))
3351 for_each_rtx (&PATTERN (subinsn), mark_constant, pool);
3352 }
3353 }
3354 else
3355 for_each_rtx (&PATTERN (insn), mark_constant, pool);
3356 }
3357
3358 /* Look through the instructions for this function, and mark all the
3359 entries in POOL which are actually being used. Emit deferred constants
3360 which have indeed been used. */
3361
3362 static void
3363 mark_constant_pool (struct rtx_constant_pool *pool)
3364 {
3365 rtx insn, link;
3366
3367 if (pool->first == 0 && n_deferred_constants == 0)
3368 return;
3369
3370 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3371 mark_constants (pool, insn);
3372
3373 for (link = current_function_epilogue_delay_list;
3374 link;
3375 link = XEXP (link, 1))
3376 mark_constants (pool, XEXP (link, 0));
3377 }
3378
3379 /* Write all the constants in the constant pool. */
3380
3381 void
3382 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
3383 tree fndecl ATTRIBUTE_UNUSED)
3384 {
3385 struct rtx_constant_pool *pool = cfun->varasm->pool;
3386 struct constant_descriptor_rtx *desc;
3387
3388 /* It is possible for gcc to call force_const_mem and then to later
3389 discard the instructions which refer to the constant. In such a
3390 case we do not need to output the constant. */
3391 mark_constant_pool (pool);
3392
3393 #ifdef ASM_OUTPUT_POOL_PROLOGUE
3394 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
3395 #endif
3396
3397 for (desc = pool->first; desc ; desc = desc->next)
3398 output_constant_pool_1 (desc);
3399
3400 #ifdef ASM_OUTPUT_POOL_EPILOGUE
3401 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
3402 #endif
3403 }
3404 \f
3405 /* Determine what kind of relocations EXP may need. */
3406
3407 int
3408 compute_reloc_for_constant (tree exp)
3409 {
3410 int reloc = 0, reloc2;
3411 tree tem;
3412
3413 /* Give the front-end a chance to convert VALUE to something that
3414 looks more like a constant to the back-end. */
3415 exp = lang_hooks.expand_constant (exp);
3416
3417 switch (TREE_CODE (exp))
3418 {
3419 case ADDR_EXPR:
3420 case FDESC_EXPR:
3421 /* Go inside any operations that get_inner_reference can handle and see
3422 if what's inside is a constant: no need to do anything here for
3423 addresses of variables or functions. */
3424 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
3425 tem = TREE_OPERAND (tem, 0))
3426 ;
3427
3428 if (TREE_PUBLIC (tem))
3429 reloc |= 2;
3430 else
3431 reloc |= 1;
3432 break;
3433
3434 case PLUS_EXPR:
3435 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3436 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
3437 break;
3438
3439 case MINUS_EXPR:
3440 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3441 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
3442 /* The difference of two local labels is computable at link time. */
3443 if (reloc == 1 && reloc2 == 1)
3444 reloc = 0;
3445 else
3446 reloc |= reloc2;
3447 break;
3448
3449 case NOP_EXPR:
3450 case CONVERT_EXPR:
3451 case NON_LVALUE_EXPR:
3452 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3453 break;
3454
3455 case CONSTRUCTOR:
3456 for (tem = CONSTRUCTOR_ELTS (exp); tem; tem = TREE_CHAIN (tem))
3457 if (TREE_VALUE (tem) != 0)
3458 reloc |= compute_reloc_for_constant (TREE_VALUE (tem));
3459
3460 break;
3461
3462 default:
3463 break;
3464 }
3465 return reloc;
3466 }
3467
3468 /* Find all the constants whose addresses are referenced inside of EXP,
3469 and make sure assembler code with a label has been output for each one.
3470 Indicate whether an ADDR_EXPR has been encountered. */
3471
3472 static void
3473 output_addressed_constants (tree exp)
3474 {
3475 tree tem;
3476
3477 /* Give the front-end a chance to convert VALUE to something that
3478 looks more like a constant to the back-end. */
3479 exp = lang_hooks.expand_constant (exp);
3480
3481 switch (TREE_CODE (exp))
3482 {
3483 case ADDR_EXPR:
3484 case FDESC_EXPR:
3485 /* Go inside any operations that get_inner_reference can handle and see
3486 if what's inside is a constant: no need to do anything here for
3487 addresses of variables or functions. */
3488 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
3489 tem = TREE_OPERAND (tem, 0))
3490 ;
3491
3492 /* If we have an initialized CONST_DECL, retrieve the initializer. */
3493 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
3494 tem = DECL_INITIAL (tem);
3495
3496 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
3497 output_constant_def (tem, 0);
3498 break;
3499
3500 case PLUS_EXPR:
3501 case MINUS_EXPR:
3502 output_addressed_constants (TREE_OPERAND (exp, 1));
3503 /* Fall through. */
3504
3505 case NOP_EXPR:
3506 case CONVERT_EXPR:
3507 case NON_LVALUE_EXPR:
3508 output_addressed_constants (TREE_OPERAND (exp, 0));
3509 break;
3510
3511 case CONSTRUCTOR:
3512 for (tem = CONSTRUCTOR_ELTS (exp); tem; tem = TREE_CHAIN (tem))
3513 if (TREE_VALUE (tem) != 0)
3514 output_addressed_constants (TREE_VALUE (tem));
3515
3516 break;
3517
3518 default:
3519 break;
3520 }
3521 }
3522 \f
3523 /* Return nonzero if VALUE is a valid constant-valued expression
3524 for use in initializing a static variable; one that can be an
3525 element of a "constant" initializer.
3526
3527 Return null_pointer_node if the value is absolute;
3528 if it is relocatable, return the variable that determines the relocation.
3529 We assume that VALUE has been folded as much as possible;
3530 therefore, we do not need to check for such things as
3531 arithmetic-combinations of integers. */
3532
3533 tree
3534 initializer_constant_valid_p (tree value, tree endtype)
3535 {
3536 /* Give the front-end a chance to convert VALUE to something that
3537 looks more like a constant to the back-end. */
3538 value = lang_hooks.expand_constant (value);
3539
3540 switch (TREE_CODE (value))
3541 {
3542 case CONSTRUCTOR:
3543 if ((TREE_CODE (TREE_TYPE (value)) == UNION_TYPE
3544 || TREE_CODE (TREE_TYPE (value)) == RECORD_TYPE)
3545 && TREE_CONSTANT (value)
3546 && CONSTRUCTOR_ELTS (value))
3547 {
3548 tree elt;
3549 bool absolute = true;
3550
3551 for (elt = CONSTRUCTOR_ELTS (value); elt; elt = TREE_CHAIN (elt))
3552 {
3553 tree reloc;
3554 value = TREE_VALUE (elt);
3555 reloc = initializer_constant_valid_p (value, TREE_TYPE (value));
3556 if (!reloc)
3557 return NULL_TREE;
3558 if (reloc != null_pointer_node)
3559 absolute = false;
3560 }
3561 /* For a non-absolute relocation, there is no single
3562 variable that can be "the variable that determines the
3563 relocation." */
3564 return absolute ? null_pointer_node : error_mark_node;
3565 }
3566
3567 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
3568
3569 case INTEGER_CST:
3570 case VECTOR_CST:
3571 case REAL_CST:
3572 case STRING_CST:
3573 case COMPLEX_CST:
3574 return null_pointer_node;
3575
3576 case ADDR_EXPR:
3577 case FDESC_EXPR:
3578 value = staticp (TREE_OPERAND (value, 0));
3579 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out to
3580 be a constant, this is old-skool offsetof-like nonsense. */
3581 if (value
3582 && TREE_CODE (value) == INDIRECT_REF
3583 && TREE_CONSTANT (TREE_OPERAND (value, 0)))
3584 return null_pointer_node;
3585 /* Taking the address of a nested function involves a trampoline. */
3586 if (value
3587 && TREE_CODE (value) == FUNCTION_DECL
3588 && ((decl_function_context (value) && !DECL_NO_STATIC_CHAIN (value))
3589 || DECL_NON_ADDR_CONST_P (value)))
3590 return NULL_TREE;
3591 return value;
3592
3593 case VIEW_CONVERT_EXPR:
3594 case NON_LVALUE_EXPR:
3595 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3596
3597 case CONVERT_EXPR:
3598 case NOP_EXPR:
3599 {
3600 tree src;
3601 tree src_type;
3602 tree dest_type;
3603
3604 src = TREE_OPERAND (value, 0);
3605 src_type = TREE_TYPE (src);
3606 dest_type = TREE_TYPE (value);
3607
3608 /* Allow conversions between pointer types, floating-point
3609 types, and offset types. */
3610 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
3611 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
3612 || (TREE_CODE (dest_type) == OFFSET_TYPE
3613 && TREE_CODE (src_type) == OFFSET_TYPE))
3614 return initializer_constant_valid_p (src, endtype);
3615
3616 /* Allow length-preserving conversions between integer types. */
3617 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
3618 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
3619 return initializer_constant_valid_p (src, endtype);
3620
3621 /* Allow conversions between other integer types only if
3622 explicit value. */
3623 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type))
3624 {
3625 tree inner = initializer_constant_valid_p (src, endtype);
3626 if (inner == null_pointer_node)
3627 return null_pointer_node;
3628 break;
3629 }
3630
3631 /* Allow (int) &foo provided int is as wide as a pointer. */
3632 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
3633 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
3634 return initializer_constant_valid_p (src, endtype);
3635
3636 /* Likewise conversions from int to pointers, but also allow
3637 conversions from 0. */
3638 if ((POINTER_TYPE_P (dest_type)
3639 || TREE_CODE (dest_type) == OFFSET_TYPE)
3640 && INTEGRAL_TYPE_P (src_type))
3641 {
3642 if (integer_zerop (src))
3643 return null_pointer_node;
3644 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
3645 return initializer_constant_valid_p (src, endtype);
3646 }
3647
3648 /* Allow conversions to struct or union types if the value
3649 inside is okay. */
3650 if (TREE_CODE (dest_type) == RECORD_TYPE
3651 || TREE_CODE (dest_type) == UNION_TYPE)
3652 return initializer_constant_valid_p (src, endtype);
3653 }
3654 break;
3655
3656 case PLUS_EXPR:
3657 if (! INTEGRAL_TYPE_P (endtype)
3658 || TYPE_PRECISION (endtype) >= POINTER_SIZE)
3659 {
3660 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0),
3661 endtype);
3662 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1),
3663 endtype);
3664 /* If either term is absolute, use the other terms relocation. */
3665 if (valid0 == null_pointer_node)
3666 return valid1;
3667 if (valid1 == null_pointer_node)
3668 return valid0;
3669 }
3670 break;
3671
3672 case MINUS_EXPR:
3673 if (! INTEGRAL_TYPE_P (endtype)
3674 || TYPE_PRECISION (endtype) >= POINTER_SIZE)
3675 {
3676 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0),
3677 endtype);
3678 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1),
3679 endtype);
3680 /* Win if second argument is absolute. */
3681 if (valid1 == null_pointer_node)
3682 return valid0;
3683 /* Win if both arguments have the same relocation.
3684 Then the value is absolute. */
3685 if (valid0 == valid1 && valid0 != 0)
3686 return null_pointer_node;
3687
3688 /* Since GCC guarantees that string constants are unique in the
3689 generated code, a subtraction between two copies of the same
3690 constant string is absolute. */
3691 if (valid0 && TREE_CODE (valid0) == STRING_CST
3692 && valid1 && TREE_CODE (valid1) == STRING_CST
3693 && operand_equal_p (valid0, valid1, 1))
3694 return null_pointer_node;
3695 }
3696
3697 /* Support narrowing differences. */
3698 if (INTEGRAL_TYPE_P (endtype))
3699 {
3700 tree op0, op1;
3701
3702 op0 = TREE_OPERAND (value, 0);
3703 op1 = TREE_OPERAND (value, 1);
3704
3705 /* Like STRIP_NOPS except allow the operand mode to widen.
3706 This works around a feature of fold that simplifies
3707 (int)(p1 - p2) to ((int)p1 - (int)p2) under the theory
3708 that the narrower operation is cheaper. */
3709
3710 while (TREE_CODE (op0) == NOP_EXPR
3711 || TREE_CODE (op0) == CONVERT_EXPR
3712 || TREE_CODE (op0) == NON_LVALUE_EXPR)
3713 {
3714 tree inner = TREE_OPERAND (op0, 0);
3715 if (inner == error_mark_node
3716 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
3717 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
3718 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
3719 break;
3720 op0 = inner;
3721 }
3722
3723 while (TREE_CODE (op1) == NOP_EXPR
3724 || TREE_CODE (op1) == CONVERT_EXPR
3725 || TREE_CODE (op1) == NON_LVALUE_EXPR)
3726 {
3727 tree inner = TREE_OPERAND (op1, 0);
3728 if (inner == error_mark_node
3729 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
3730 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
3731 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
3732 break;
3733 op1 = inner;
3734 }
3735
3736 op0 = initializer_constant_valid_p (op0, endtype);
3737 op1 = initializer_constant_valid_p (op1, endtype);
3738
3739 /* Both initializers must be known. */
3740 if (op0 && op1)
3741 {
3742 if (op0 == op1)
3743 return null_pointer_node;
3744
3745 /* Support differences between labels. */
3746 if (TREE_CODE (op0) == LABEL_DECL
3747 && TREE_CODE (op1) == LABEL_DECL)
3748 return null_pointer_node;
3749
3750 if (TREE_CODE (op0) == STRING_CST
3751 && TREE_CODE (op1) == STRING_CST
3752 && operand_equal_p (op0, op1, 1))
3753 return null_pointer_node;
3754 }
3755 }
3756 break;
3757
3758 default:
3759 break;
3760 }
3761
3762 return 0;
3763 }
3764 \f
3765 /* Output assembler code for constant EXP to FILE, with no label.
3766 This includes the pseudo-op such as ".int" or ".byte", and a newline.
3767 Assumes output_addressed_constants has been done on EXP already.
3768
3769 Generate exactly SIZE bytes of assembler data, padding at the end
3770 with zeros if necessary. SIZE must always be specified.
3771
3772 SIZE is important for structure constructors,
3773 since trailing members may have been omitted from the constructor.
3774 It is also important for initialization of arrays from string constants
3775 since the full length of the string constant might not be wanted.
3776 It is also needed for initialization of unions, where the initializer's
3777 type is just one member, and that may not be as long as the union.
3778
3779 There a case in which we would fail to output exactly SIZE bytes:
3780 for a structure constructor that wants to produce more than SIZE bytes.
3781 But such constructors will never be generated for any possible input.
3782
3783 ALIGN is the alignment of the data in bits. */
3784
3785 void
3786 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align)
3787 {
3788 enum tree_code code;
3789 unsigned HOST_WIDE_INT thissize;
3790
3791 /* Some front-ends use constants other than the standard language-independent
3792 varieties, but which may still be output directly. Give the front-end a
3793 chance to convert EXP to a language-independent representation. */
3794 exp = lang_hooks.expand_constant (exp);
3795
3796 if (size == 0 || flag_syntax_only)
3797 return;
3798
3799 /* Eliminate any conversions since we'll be outputting the underlying
3800 constant. */
3801 while (TREE_CODE (exp) == NOP_EXPR || TREE_CODE (exp) == CONVERT_EXPR
3802 || TREE_CODE (exp) == NON_LVALUE_EXPR
3803 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
3804 exp = TREE_OPERAND (exp, 0);
3805
3806 code = TREE_CODE (TREE_TYPE (exp));
3807 thissize = int_size_in_bytes (TREE_TYPE (exp));
3808
3809 /* Allow a constructor with no elements for any data type.
3810 This means to fill the space with zeros. */
3811 if (TREE_CODE (exp) == CONSTRUCTOR && CONSTRUCTOR_ELTS (exp) == 0)
3812 {
3813 assemble_zeros (size);
3814 return;
3815 }
3816
3817 if (TREE_CODE (exp) == FDESC_EXPR)
3818 {
3819 #ifdef ASM_OUTPUT_FDESC
3820 HOST_WIDE_INT part = tree_low_cst (TREE_OPERAND (exp, 1), 0);
3821 tree decl = TREE_OPERAND (exp, 0);
3822 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
3823 #else
3824 gcc_unreachable ();
3825 #endif
3826 return;
3827 }
3828
3829 /* Now output the underlying data. If we've handling the padding, return.
3830 Otherwise, break and ensure SIZE is the size written. */
3831 switch (code)
3832 {
3833 case CHAR_TYPE:
3834 case BOOLEAN_TYPE:
3835 case INTEGER_TYPE:
3836 case ENUMERAL_TYPE:
3837 case POINTER_TYPE:
3838 case REFERENCE_TYPE:
3839 case OFFSET_TYPE:
3840 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
3841 EXPAND_INITIALIZER),
3842 MIN (size, thissize), align, 0))
3843 error ("initializer for integer value is too complicated");
3844 break;
3845
3846 case REAL_TYPE:
3847 if (TREE_CODE (exp) != REAL_CST)
3848 error ("initializer for floating value is not a floating constant");
3849
3850 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)), align);
3851 break;
3852
3853 case COMPLEX_TYPE:
3854 output_constant (TREE_REALPART (exp), thissize / 2, align);
3855 output_constant (TREE_IMAGPART (exp), thissize / 2,
3856 min_align (align, BITS_PER_UNIT * (thissize / 2)));
3857 break;
3858
3859 case ARRAY_TYPE:
3860 case VECTOR_TYPE:
3861 switch (TREE_CODE (exp))
3862 {
3863 case CONSTRUCTOR:
3864 output_constructor (exp, size, align);
3865 return;
3866 case STRING_CST:
3867 thissize = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp),
3868 size);
3869 assemble_string (TREE_STRING_POINTER (exp), thissize);
3870 break;
3871
3872 case VECTOR_CST:
3873 {
3874 int elt_size;
3875 tree link;
3876 unsigned int nalign;
3877 enum machine_mode inner;
3878
3879 inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
3880 nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
3881
3882 elt_size = GET_MODE_SIZE (inner);
3883
3884 link = TREE_VECTOR_CST_ELTS (exp);
3885 output_constant (TREE_VALUE (link), elt_size, align);
3886 while ((link = TREE_CHAIN (link)) != NULL)
3887 output_constant (TREE_VALUE (link), elt_size, nalign);
3888 break;
3889 }
3890 default:
3891 gcc_unreachable ();
3892 }
3893 break;
3894
3895 case RECORD_TYPE:
3896 case UNION_TYPE:
3897 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
3898 output_constructor (exp, size, align);
3899 return;
3900
3901 case ERROR_MARK:
3902 return;
3903
3904 default:
3905 gcc_unreachable ();
3906 }
3907
3908 if (size > thissize)
3909 assemble_zeros (size - thissize);
3910 }
3911
3912 \f
3913 /* Subroutine of output_constructor, used for computing the size of
3914 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
3915 type with an unspecified upper bound. */
3916
3917 static unsigned HOST_WIDE_INT
3918 array_size_for_constructor (tree val)
3919 {
3920 tree max_index, i;
3921
3922 /* This code used to attempt to handle string constants that are not
3923 arrays of single-bytes, but nothing else does, so there's no point in
3924 doing it here. */
3925 if (TREE_CODE (val) == STRING_CST)
3926 return TREE_STRING_LENGTH (val);
3927
3928 max_index = NULL_TREE;
3929 for (i = CONSTRUCTOR_ELTS (val); i; i = TREE_CHAIN (i))
3930 {
3931 tree index = TREE_PURPOSE (i);
3932
3933 if (TREE_CODE (index) == RANGE_EXPR)
3934 index = TREE_OPERAND (index, 1);
3935 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
3936 max_index = index;
3937 }
3938
3939 if (max_index == NULL_TREE)
3940 return 0;
3941
3942 /* Compute the total number of array elements. */
3943 i = size_binop (MINUS_EXPR, convert (sizetype, max_index),
3944 convert (sizetype,
3945 TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)))));
3946 i = size_binop (PLUS_EXPR, i, convert (sizetype, integer_one_node));
3947
3948 /* Multiply by the array element unit size to find number of bytes. */
3949 i = size_binop (MULT_EXPR, i, TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
3950
3951 return tree_low_cst (i, 1);
3952 }
3953
3954 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
3955 Generate at least SIZE bytes, padding if necessary. */
3956
3957 static void
3958 output_constructor (tree exp, unsigned HOST_WIDE_INT size,
3959 unsigned int align)
3960 {
3961 tree type = TREE_TYPE (exp);
3962 tree link, field = 0;
3963 tree min_index = 0;
3964 /* Number of bytes output or skipped so far.
3965 In other words, current position within the constructor. */
3966 HOST_WIDE_INT total_bytes = 0;
3967 /* Nonzero means BYTE contains part of a byte, to be output. */
3968 int byte_buffer_in_use = 0;
3969 int byte = 0;
3970
3971 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
3972
3973 if (TREE_CODE (type) == RECORD_TYPE)
3974 field = TYPE_FIELDS (type);
3975
3976 if (TREE_CODE (type) == ARRAY_TYPE
3977 && TYPE_DOMAIN (type) != 0)
3978 min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (type));
3979
3980 /* As LINK goes through the elements of the constant,
3981 FIELD goes through the structure fields, if the constant is a structure.
3982 if the constant is a union, then we override this,
3983 by getting the field from the TREE_LIST element.
3984 But the constant could also be an array. Then FIELD is zero.
3985
3986 There is always a maximum of one element in the chain LINK for unions
3987 (even if the initializer in a source program incorrectly contains
3988 more one). */
3989 for (link = CONSTRUCTOR_ELTS (exp);
3990 link;
3991 link = TREE_CHAIN (link),
3992 field = field ? TREE_CHAIN (field) : 0)
3993 {
3994 tree val = TREE_VALUE (link);
3995 tree index = 0;
3996
3997 /* The element in a union constructor specifies the proper field
3998 or index. */
3999 if ((TREE_CODE (type) == RECORD_TYPE || TREE_CODE (type) == UNION_TYPE
4000 || TREE_CODE (type) == QUAL_UNION_TYPE)
4001 && TREE_PURPOSE (link) != 0)
4002 field = TREE_PURPOSE (link);
4003
4004 else if (TREE_CODE (type) == ARRAY_TYPE)
4005 index = TREE_PURPOSE (link);
4006
4007 #ifdef ASM_COMMENT_START
4008 if (field && flag_verbose_asm)
4009 fprintf (asm_out_file, "%s %s:\n",
4010 ASM_COMMENT_START,
4011 DECL_NAME (field)
4012 ? IDENTIFIER_POINTER (DECL_NAME (field))
4013 : "<anonymous>");
4014 #endif
4015
4016 /* Eliminate the marker that makes a cast not be an lvalue. */
4017 if (val != 0)
4018 STRIP_NOPS (val);
4019
4020 if (index && TREE_CODE (index) == RANGE_EXPR)
4021 {
4022 unsigned HOST_WIDE_INT fieldsize
4023 = int_size_in_bytes (TREE_TYPE (type));
4024 HOST_WIDE_INT lo_index = tree_low_cst (TREE_OPERAND (index, 0), 0);
4025 HOST_WIDE_INT hi_index = tree_low_cst (TREE_OPERAND (index, 1), 0);
4026 HOST_WIDE_INT index;
4027 unsigned int align2 = min_align (align, fieldsize * BITS_PER_UNIT);
4028
4029 for (index = lo_index; index <= hi_index; index++)
4030 {
4031 /* Output the element's initial value. */
4032 if (val == 0)
4033 assemble_zeros (fieldsize);
4034 else
4035 output_constant (val, fieldsize, align2);
4036
4037 /* Count its size. */
4038 total_bytes += fieldsize;
4039 }
4040 }
4041 else if (field == 0 || !DECL_BIT_FIELD (field))
4042 {
4043 /* An element that is not a bit-field. */
4044
4045 unsigned HOST_WIDE_INT fieldsize;
4046 /* Since this structure is static,
4047 we know the positions are constant. */
4048 HOST_WIDE_INT pos = field ? int_byte_position (field) : 0;
4049 unsigned int align2;
4050
4051 if (index != 0)
4052 pos = (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (val)), 1)
4053 * (tree_low_cst (index, 0) - tree_low_cst (min_index, 0)));
4054
4055 /* Output any buffered-up bit-fields preceding this element. */
4056 if (byte_buffer_in_use)
4057 {
4058 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4059 total_bytes++;
4060 byte_buffer_in_use = 0;
4061 }
4062
4063 /* Advance to offset of this element.
4064 Note no alignment needed in an array, since that is guaranteed
4065 if each element has the proper size. */
4066 if ((field != 0 || index != 0) && pos != total_bytes)
4067 {
4068 assemble_zeros (pos - total_bytes);
4069 total_bytes = pos;
4070 }
4071
4072 /* Find the alignment of this element. */
4073 align2 = min_align (align, BITS_PER_UNIT * pos);
4074
4075 /* Determine size this element should occupy. */
4076 if (field)
4077 {
4078 fieldsize = 0;
4079
4080 /* If this is an array with an unspecified upper bound,
4081 the initializer determines the size. */
4082 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
4083 but we cannot do this until the deprecated support for
4084 initializing zero-length array members is removed. */
4085 if (TREE_CODE (TREE_TYPE (field)) == ARRAY_TYPE
4086 && TYPE_DOMAIN (TREE_TYPE (field))
4087 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (field))))
4088 {
4089 fieldsize = array_size_for_constructor (val);
4090 /* Given a non-empty initialization, this field had
4091 better be last. */
4092 gcc_assert (!fieldsize || !TREE_CHAIN (field));
4093 }
4094 else if (DECL_SIZE_UNIT (field))
4095 {
4096 /* ??? This can't be right. If the decl size overflows
4097 a host integer we will silently emit no data. */
4098 if (host_integerp (DECL_SIZE_UNIT (field), 1))
4099 fieldsize = tree_low_cst (DECL_SIZE_UNIT (field), 1);
4100 }
4101 }
4102 else
4103 fieldsize = int_size_in_bytes (TREE_TYPE (type));
4104
4105 /* Output the element's initial value. */
4106 if (val == 0)
4107 assemble_zeros (fieldsize);
4108 else
4109 output_constant (val, fieldsize, align2);
4110
4111 /* Count its size. */
4112 total_bytes += fieldsize;
4113 }
4114 else if (val != 0 && TREE_CODE (val) != INTEGER_CST)
4115 error ("invalid initial value for member %qs",
4116 IDENTIFIER_POINTER (DECL_NAME (field)));
4117 else
4118 {
4119 /* Element that is a bit-field. */
4120
4121 HOST_WIDE_INT next_offset = int_bit_position (field);
4122 HOST_WIDE_INT end_offset
4123 = (next_offset + tree_low_cst (DECL_SIZE (field), 1));
4124
4125 if (val == 0)
4126 val = integer_zero_node;
4127
4128 /* If this field does not start in this (or, next) byte,
4129 skip some bytes. */
4130 if (next_offset / BITS_PER_UNIT != total_bytes)
4131 {
4132 /* Output remnant of any bit field in previous bytes. */
4133 if (byte_buffer_in_use)
4134 {
4135 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4136 total_bytes++;
4137 byte_buffer_in_use = 0;
4138 }
4139
4140 /* If still not at proper byte, advance to there. */
4141 if (next_offset / BITS_PER_UNIT != total_bytes)
4142 {
4143 assemble_zeros (next_offset / BITS_PER_UNIT - total_bytes);
4144 total_bytes = next_offset / BITS_PER_UNIT;
4145 }
4146 }
4147
4148 if (! byte_buffer_in_use)
4149 byte = 0;
4150
4151 /* We must split the element into pieces that fall within
4152 separate bytes, and combine each byte with previous or
4153 following bit-fields. */
4154
4155 /* next_offset is the offset n fbits from the beginning of
4156 the structure to the next bit of this element to be processed.
4157 end_offset is the offset of the first bit past the end of
4158 this element. */
4159 while (next_offset < end_offset)
4160 {
4161 int this_time;
4162 int shift;
4163 HOST_WIDE_INT value;
4164 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
4165 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
4166
4167 /* Advance from byte to byte
4168 within this element when necessary. */
4169 while (next_byte != total_bytes)
4170 {
4171 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4172 total_bytes++;
4173 byte = 0;
4174 }
4175
4176 /* Number of bits we can process at once
4177 (all part of the same byte). */
4178 this_time = MIN (end_offset - next_offset,
4179 BITS_PER_UNIT - next_bit);
4180 if (BYTES_BIG_ENDIAN)
4181 {
4182 /* On big-endian machine, take the most significant bits
4183 first (of the bits that are significant)
4184 and put them into bytes from the most significant end. */
4185 shift = end_offset - next_offset - this_time;
4186
4187 /* Don't try to take a bunch of bits that cross
4188 the word boundary in the INTEGER_CST. We can
4189 only select bits from the LOW or HIGH part
4190 not from both. */
4191 if (shift < HOST_BITS_PER_WIDE_INT
4192 && shift + this_time > HOST_BITS_PER_WIDE_INT)
4193 {
4194 this_time = shift + this_time - HOST_BITS_PER_WIDE_INT;
4195 shift = HOST_BITS_PER_WIDE_INT;
4196 }
4197
4198 /* Now get the bits from the appropriate constant word. */
4199 if (shift < HOST_BITS_PER_WIDE_INT)
4200 value = TREE_INT_CST_LOW (val);
4201 else
4202 {
4203 gcc_assert (shift < 2 * HOST_BITS_PER_WIDE_INT);
4204 value = TREE_INT_CST_HIGH (val);
4205 shift -= HOST_BITS_PER_WIDE_INT;
4206 }
4207
4208 /* Get the result. This works only when:
4209 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
4210 byte |= (((value >> shift)
4211 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
4212 << (BITS_PER_UNIT - this_time - next_bit));
4213 }
4214 else
4215 {
4216 /* On little-endian machines,
4217 take first the least significant bits of the value
4218 and pack them starting at the least significant
4219 bits of the bytes. */
4220 shift = next_offset - int_bit_position (field);
4221
4222 /* Don't try to take a bunch of bits that cross
4223 the word boundary in the INTEGER_CST. We can
4224 only select bits from the LOW or HIGH part
4225 not from both. */
4226 if (shift < HOST_BITS_PER_WIDE_INT
4227 && shift + this_time > HOST_BITS_PER_WIDE_INT)
4228 this_time = (HOST_BITS_PER_WIDE_INT - shift);
4229
4230 /* Now get the bits from the appropriate constant word. */
4231 if (shift < HOST_BITS_PER_WIDE_INT)
4232 value = TREE_INT_CST_LOW (val);
4233 else
4234 {
4235 gcc_assert (shift < 2 * HOST_BITS_PER_WIDE_INT);
4236 value = TREE_INT_CST_HIGH (val);
4237 shift -= HOST_BITS_PER_WIDE_INT;
4238 }
4239
4240 /* Get the result. This works only when:
4241 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
4242 byte |= (((value >> shift)
4243 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
4244 << next_bit);
4245 }
4246
4247 next_offset += this_time;
4248 byte_buffer_in_use = 1;
4249 }
4250 }
4251 }
4252
4253 if (byte_buffer_in_use)
4254 {
4255 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4256 total_bytes++;
4257 }
4258
4259 if ((unsigned HOST_WIDE_INT)total_bytes < size)
4260 assemble_zeros (size - total_bytes);
4261 }
4262
4263 /* This TREE_LIST contains any weak symbol declarations waiting
4264 to be emitted. */
4265 static GTY(()) tree weak_decls;
4266
4267 /* Mark DECL as weak. */
4268
4269 static void
4270 mark_weak (tree decl)
4271 {
4272 DECL_WEAK (decl) = 1;
4273
4274 if (DECL_RTL_SET_P (decl)
4275 && MEM_P (DECL_RTL (decl))
4276 && XEXP (DECL_RTL (decl), 0)
4277 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
4278 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
4279 }
4280
4281 /* Merge weak status between NEWDECL and OLDDECL. */
4282
4283 void
4284 merge_weak (tree newdecl, tree olddecl)
4285 {
4286 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
4287 return;
4288
4289 if (DECL_WEAK (newdecl))
4290 {
4291 tree wd;
4292
4293 /* NEWDECL is weak, but OLDDECL is not. */
4294
4295 /* If we already output the OLDDECL, we're in trouble; we can't
4296 go back and make it weak. This error cannot caught in
4297 declare_weak because the NEWDECL and OLDDECL was not yet
4298 been merged; therefore, TREE_ASM_WRITTEN was not set. */
4299 if (TREE_ASM_WRITTEN (olddecl))
4300 error ("%Jweak declaration of %qD must precede definition",
4301 newdecl, newdecl);
4302
4303 /* If we've already generated rtl referencing OLDDECL, we may
4304 have done so in a way that will not function properly with
4305 a weak symbol. */
4306 else if (TREE_USED (olddecl)
4307 && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)))
4308 warning ("%Jweak declaration of %qD after first use results "
4309 "in unspecified behavior", newdecl, newdecl);
4310
4311 if (SUPPORTS_WEAK)
4312 {
4313 /* We put the NEWDECL on the weak_decls list at some point.
4314 Replace it with the OLDDECL. */
4315 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
4316 if (TREE_VALUE (wd) == newdecl)
4317 {
4318 TREE_VALUE (wd) = olddecl;
4319 break;
4320 }
4321 /* We may not find the entry on the list. If NEWDECL is a
4322 weak alias, then we will have already called
4323 globalize_decl to remove the entry; in that case, we do
4324 not need to do anything. */
4325 }
4326
4327 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
4328 mark_weak (olddecl);
4329 }
4330 else
4331 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
4332 weak. Just update NEWDECL to indicate that it's weak too. */
4333 mark_weak (newdecl);
4334 }
4335
4336 /* Declare DECL to be a weak symbol. */
4337
4338 void
4339 declare_weak (tree decl)
4340 {
4341 if (! TREE_PUBLIC (decl))
4342 error ("%Jweak declaration of %qD must be public", decl, decl);
4343 else if (TREE_CODE (decl) == FUNCTION_DECL && TREE_ASM_WRITTEN (decl))
4344 error ("%Jweak declaration of %qD must precede definition", decl, decl);
4345 else if (SUPPORTS_WEAK)
4346 {
4347 if (! DECL_WEAK (decl))
4348 weak_decls = tree_cons (NULL, decl, weak_decls);
4349 }
4350 else
4351 warning ("%Jweak declaration of %qD not supported", decl, decl);
4352
4353 mark_weak (decl);
4354 }
4355
4356 /* Emit any pending weak declarations. */
4357
4358 void
4359 weak_finish (void)
4360 {
4361 tree t;
4362
4363 for (t = weak_decls; t; t = TREE_CHAIN (t))
4364 {
4365 tree decl = TREE_VALUE (t);
4366 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
4367 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
4368 #endif
4369
4370 if (! TREE_USED (decl))
4371 continue;
4372
4373 #ifdef ASM_WEAKEN_DECL
4374 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
4375 #else
4376 #ifdef ASM_WEAKEN_LABEL
4377 ASM_WEAKEN_LABEL (asm_out_file, name);
4378 #else
4379 #ifdef ASM_OUTPUT_WEAK_ALIAS
4380 warning ("only weak aliases are supported in this configuration");
4381 return;
4382 #endif
4383 #endif
4384 #endif
4385 }
4386 }
4387
4388 /* Emit the assembly bits to indicate that DECL is globally visible. */
4389
4390 static void
4391 globalize_decl (tree decl)
4392 {
4393 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
4394
4395 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
4396 if (DECL_WEAK (decl))
4397 {
4398 tree *p, t;
4399
4400 #ifdef ASM_WEAKEN_DECL
4401 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
4402 #else
4403 ASM_WEAKEN_LABEL (asm_out_file, name);
4404 #endif
4405
4406 /* Remove this function from the pending weak list so that
4407 we do not emit multiple .weak directives for it. */
4408 for (p = &weak_decls; (t = *p) ; )
4409 {
4410 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
4411 *p = TREE_CHAIN (t);
4412 else
4413 p = &TREE_CHAIN (t);
4414 }
4415 return;
4416 }
4417 #elif defined(ASM_MAKE_LABEL_LINKONCE)
4418 if (DECL_ONE_ONLY (decl))
4419 ASM_MAKE_LABEL_LINKONCE (asm_out_file, name);
4420 #endif
4421
4422 targetm.asm_out.globalize_label (asm_out_file, name);
4423 }
4424
4425 /* We have to be able to tell cgraph about the needed-ness of the target
4426 of an alias. This requires that the decl have been defined. Aliases
4427 that precede their definition have to be queued for later processing. */
4428
4429 typedef struct alias_pair GTY(())
4430 {
4431 tree decl;
4432 tree target;
4433 } alias_pair;
4434
4435 /* Define gc'd vector type. */
4436 DEF_VEC_O(alias_pair);
4437 DEF_VEC_ALLOC_O(alias_pair,gc);
4438
4439 static GTY(()) VEC(alias_pair,gc) *alias_pairs;
4440
4441 /* Given an assembly name, find the decl it is associated with. At the
4442 same time, mark it needed for cgraph. */
4443
4444 static tree
4445 find_decl_and_mark_needed (tree decl, tree target)
4446 {
4447 struct cgraph_node *fnode = NULL;
4448 struct cgraph_varpool_node *vnode = NULL;
4449
4450 /* C++ thunk emitting code produces aliases late in the game.
4451 Avoid confusing cgraph code in that case. */
4452 if (!cgraph_global_info_ready)
4453 {
4454 if (TREE_CODE (decl) == FUNCTION_DECL)
4455 {
4456 fnode = cgraph_node_for_asm (target);
4457 if (fnode == NULL)
4458 vnode = cgraph_varpool_node_for_asm (target);
4459 }
4460 else
4461 {
4462 vnode = cgraph_varpool_node_for_asm (target);
4463 if (vnode == NULL)
4464 fnode = cgraph_node_for_asm (target);
4465 }
4466 }
4467
4468 if (fnode)
4469 {
4470 cgraph_mark_needed_node (fnode);
4471 return fnode->decl;
4472 }
4473 else if (vnode)
4474 {
4475 cgraph_varpool_mark_needed_node (vnode);
4476 return vnode->decl;
4477 }
4478 else
4479 return NULL_TREE;
4480 }
4481
4482 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
4483 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
4484 tree node is DECL to have the value of the tree node TARGET. */
4485
4486 static void
4487 do_assemble_alias (tree decl, tree target ATTRIBUTE_UNUSED)
4488 {
4489 TREE_ASM_WRITTEN (decl) = 1;
4490 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
4491
4492 #ifdef ASM_OUTPUT_DEF
4493 /* Make name accessible from other files, if appropriate. */
4494
4495 if (TREE_PUBLIC (decl))
4496 {
4497 globalize_decl (decl);
4498 maybe_assemble_visibility (decl);
4499 }
4500
4501 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
4502 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
4503 # else
4504 ASM_OUTPUT_DEF (asm_out_file,
4505 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
4506 IDENTIFIER_POINTER (target));
4507 # endif
4508 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
4509 {
4510 const char *name;
4511 tree *p, t;
4512
4513 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
4514 # ifdef ASM_WEAKEN_DECL
4515 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
4516 # else
4517 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
4518 # endif
4519 /* Remove this function from the pending weak list so that
4520 we do not emit multiple .weak directives for it. */
4521 for (p = &weak_decls; (t = *p) ; )
4522 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
4523 *p = TREE_CHAIN (t);
4524 else
4525 p = &TREE_CHAIN (t);
4526 }
4527 #endif
4528 }
4529
4530 /* First pass of completing pending aliases. Make sure that cgraph knows
4531 which symbols will be required. */
4532
4533 void
4534 finish_aliases_1 (void)
4535 {
4536 unsigned i;
4537 alias_pair *p;
4538
4539 for (i = 0; VEC_iterate (alias_pair, alias_pairs, i, p); i++)
4540 {
4541 tree target_decl;
4542
4543 target_decl = find_decl_and_mark_needed (p->decl, p->target);
4544 if (target_decl == NULL)
4545 error ("%J%qD aliased to undefined symbol %qE",
4546 p->decl, p->decl, p->target);
4547 else if (DECL_EXTERNAL (target_decl))
4548 error ("%J%qD aliased to external symbol %qE",
4549 p->decl, p->decl, p->target);
4550 }
4551 }
4552
4553 /* Second pass of completing pending aliases. Emit the actual assembly.
4554 This happens at the end of compilation and thus it is assured that the
4555 target symbol has been emitted. */
4556
4557 void
4558 finish_aliases_2 (void)
4559 {
4560 unsigned i;
4561 alias_pair *p;
4562
4563 for (i = 0; VEC_iterate (alias_pair, alias_pairs, i, p); i++)
4564 do_assemble_alias (p->decl, p->target);
4565
4566 VEC_truncate (alias_pair, alias_pairs, 0);
4567 }
4568
4569 /* Emit an assembler directive to make the symbol for DECL an alias to
4570 the symbol for TARGET. */
4571
4572 void
4573 assemble_alias (tree decl, tree target)
4574 {
4575 tree target_decl;
4576
4577 #if !defined (ASM_OUTPUT_DEF)
4578 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
4579 error ("%Jalias definitions not supported in this configuration", decl);
4580 return;
4581 # else
4582 if (!DECL_WEAK (decl))
4583 {
4584 error ("%Jonly weak aliases are supported in this configuration", decl);
4585 return;
4586 }
4587 # endif
4588 #endif
4589
4590 /* We must force creation of DECL_RTL for debug info generation, even though
4591 we don't use it here. */
4592 make_decl_rtl (decl);
4593 TREE_USED (decl) = 1;
4594
4595 /* A quirk of the initial implementation of aliases required that the user
4596 add "extern" to all of them. Which is silly, but now historical. Do
4597 note that the symbol is in fact locally defined. */
4598 DECL_EXTERNAL (decl) = 0;
4599
4600 /* Allow aliases to aliases. */
4601 if (TREE_CODE (decl) == FUNCTION_DECL)
4602 cgraph_node (decl)->alias = true;
4603 else
4604 cgraph_varpool_node (decl)->alias = true;
4605
4606 /* If the target has already been emitted, we don't have to queue the
4607 alias. This saves a tad o memory. */
4608 target_decl = find_decl_and_mark_needed (decl, target);
4609 if (target_decl && TREE_ASM_WRITTEN (target_decl))
4610 do_assemble_alias (decl, target);
4611 else
4612 {
4613 alias_pair *p = VEC_safe_push (alias_pair, gc, alias_pairs, NULL);
4614 p->decl = decl;
4615 p->target = target;
4616 }
4617 }
4618
4619 /* Emit an assembler directive to set symbol for DECL visibility to
4620 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
4621
4622 void
4623 default_assemble_visibility (tree decl, int vis)
4624 {
4625 static const char * const visibility_types[] = {
4626 NULL, "internal", "hidden", "protected"
4627 };
4628
4629 const char *name, *type;
4630
4631 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
4632 type = visibility_types[vis];
4633
4634 #ifdef HAVE_GAS_HIDDEN
4635 fprintf (asm_out_file, "\t.%s\t", type);
4636 assemble_name (asm_out_file, name);
4637 fprintf (asm_out_file, "\n");
4638 #else
4639 warning ("visibility attribute not supported in this configuration; ignored");
4640 #endif
4641 }
4642
4643 /* A helper function to call assemble_visibility when needed for a decl. */
4644
4645 static void
4646 maybe_assemble_visibility (tree decl)
4647 {
4648 enum symbol_visibility vis = DECL_VISIBILITY (decl);
4649
4650 if (vis != VISIBILITY_DEFAULT)
4651 targetm.asm_out.visibility (decl, vis);
4652 }
4653
4654 /* Returns 1 if the target configuration supports defining public symbols
4655 so that one of them will be chosen at link time instead of generating a
4656 multiply-defined symbol error, whether through the use of weak symbols or
4657 a target-specific mechanism for having duplicates discarded. */
4658
4659 int
4660 supports_one_only (void)
4661 {
4662 if (SUPPORTS_ONE_ONLY)
4663 return 1;
4664 return SUPPORTS_WEAK;
4665 }
4666
4667 /* Set up DECL as a public symbol that can be defined in multiple
4668 translation units without generating a linker error. */
4669
4670 void
4671 make_decl_one_only (tree decl)
4672 {
4673 gcc_assert (TREE_CODE (decl) == VAR_DECL
4674 || TREE_CODE (decl) == FUNCTION_DECL);
4675
4676 TREE_PUBLIC (decl) = 1;
4677
4678 if (SUPPORTS_ONE_ONLY)
4679 {
4680 #ifdef MAKE_DECL_ONE_ONLY
4681 MAKE_DECL_ONE_ONLY (decl);
4682 #endif
4683 DECL_ONE_ONLY (decl) = 1;
4684 }
4685 else if (TREE_CODE (decl) == VAR_DECL
4686 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node))
4687 DECL_COMMON (decl) = 1;
4688 else
4689 {
4690 gcc_assert (SUPPORTS_WEAK);
4691 DECL_WEAK (decl) = 1;
4692 }
4693 }
4694
4695 void
4696 init_varasm_once (void)
4697 {
4698 in_named_htab = htab_create_ggc (31, in_named_entry_hash,
4699 in_named_entry_eq, NULL);
4700 const_desc_htab = htab_create_ggc (1009, const_desc_hash,
4701 const_desc_eq, NULL);
4702
4703 const_alias_set = new_alias_set ();
4704 }
4705
4706 static enum tls_model
4707 decl_tls_model (tree decl)
4708 {
4709 enum tls_model kind;
4710 tree attr = lookup_attribute ("tls_model", DECL_ATTRIBUTES (decl));
4711 bool is_local;
4712
4713 if (attr)
4714 {
4715 attr = TREE_VALUE (TREE_VALUE (attr));
4716 gcc_assert (TREE_CODE (attr) == STRING_CST);
4717
4718 if (!strcmp (TREE_STRING_POINTER (attr), "local-exec"))
4719 kind = TLS_MODEL_LOCAL_EXEC;
4720 else if (!strcmp (TREE_STRING_POINTER (attr), "initial-exec"))
4721 kind = TLS_MODEL_INITIAL_EXEC;
4722 else if (!strcmp (TREE_STRING_POINTER (attr), "local-dynamic"))
4723 kind = optimize ? TLS_MODEL_LOCAL_DYNAMIC : TLS_MODEL_GLOBAL_DYNAMIC;
4724 else if (!strcmp (TREE_STRING_POINTER (attr), "global-dynamic"))
4725 kind = TLS_MODEL_GLOBAL_DYNAMIC;
4726 else
4727 gcc_unreachable ();
4728 return kind;
4729 }
4730
4731 is_local = targetm.binds_local_p (decl);
4732 if (!flag_shlib)
4733 {
4734 if (is_local)
4735 kind = TLS_MODEL_LOCAL_EXEC;
4736 else
4737 kind = TLS_MODEL_INITIAL_EXEC;
4738 }
4739 /* Local dynamic is inefficient when we're not combining the
4740 parts of the address. */
4741 else if (optimize && is_local)
4742 kind = TLS_MODEL_LOCAL_DYNAMIC;
4743 else
4744 kind = TLS_MODEL_GLOBAL_DYNAMIC;
4745 if (kind < flag_tls_default)
4746 kind = flag_tls_default;
4747
4748 return kind;
4749 }
4750
4751 /* Select a set of attributes for section NAME based on the properties
4752 of DECL and whether or not RELOC indicates that DECL's initializer
4753 might contain runtime relocations.
4754
4755 We make the section read-only and executable for a function decl,
4756 read-only for a const data decl, and writable for a non-const data decl. */
4757
4758 unsigned int
4759 default_section_type_flags (tree decl, const char *name, int reloc)
4760 {
4761 return default_section_type_flags_1 (decl, name, reloc, flag_pic);
4762 }
4763
4764 unsigned int
4765 default_section_type_flags_1 (tree decl, const char *name, int reloc,
4766 int shlib)
4767 {
4768 unsigned int flags;
4769
4770 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
4771 flags = SECTION_CODE;
4772 else if (decl && decl_readonly_section_1 (decl, reloc, shlib))
4773 flags = 0;
4774 else if (unlikely_text_section_name
4775 && strcmp (name, unlikely_text_section_name) == 0)
4776 flags = SECTION_CODE;
4777 else
4778 flags = SECTION_WRITE;
4779
4780 if (decl && DECL_ONE_ONLY (decl))
4781 flags |= SECTION_LINKONCE;
4782
4783 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl))
4784 flags |= SECTION_TLS | SECTION_WRITE;
4785
4786 if (strcmp (name, ".bss") == 0
4787 || strncmp (name, ".bss.", 5) == 0
4788 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
4789 || strcmp (name, ".sbss") == 0
4790 || strncmp (name, ".sbss.", 6) == 0
4791 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
4792 flags |= SECTION_BSS;
4793
4794 if (strcmp (name, ".tdata") == 0
4795 || strncmp (name, ".tdata.", 7) == 0
4796 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
4797 flags |= SECTION_TLS;
4798
4799 if (strcmp (name, ".tbss") == 0
4800 || strncmp (name, ".tbss.", 6) == 0
4801 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
4802 flags |= SECTION_TLS | SECTION_BSS;
4803
4804 /* These three sections have special ELF types. They are neither
4805 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
4806 want to print a section type (@progbits or @nobits). If someone
4807 is silly enough to emit code or TLS variables to one of these
4808 sections, then don't handle them specially. */
4809 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
4810 && (strcmp (name, ".init_array") == 0
4811 || strcmp (name, ".fini_array") == 0
4812 || strcmp (name, ".preinit_array") == 0))
4813 flags |= SECTION_NOTYPE;
4814
4815 return flags;
4816 }
4817
4818 /* Output assembly to switch to section NAME with attribute FLAGS.
4819 Four variants for common object file formats. */
4820
4821 void
4822 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
4823 unsigned int flags ATTRIBUTE_UNUSED,
4824 tree decl ATTRIBUTE_UNUSED)
4825 {
4826 /* Some object formats don't support named sections at all. The
4827 front-end should already have flagged this as an error. */
4828 gcc_unreachable ();
4829 }
4830
4831 void
4832 default_elf_asm_named_section (const char *name, unsigned int flags,
4833 tree decl ATTRIBUTE_UNUSED)
4834 {
4835 char flagchars[10], *f = flagchars;
4836
4837 /* If we have already declared this section, we can use an
4838 abbreviated form to switch back to it -- unless this section is
4839 part of a COMDAT groups, in which case GAS requires the full
4840 declaration every time. */
4841 if (!(HAVE_GAS_COMDAT_GROUP && (flags & SECTION_LINKONCE))
4842 && ! named_section_first_declaration (name))
4843 {
4844 fprintf (asm_out_file, "\t.section\t%s\n", name);
4845 return;
4846 }
4847
4848 if (!(flags & SECTION_DEBUG))
4849 *f++ = 'a';
4850 if (flags & SECTION_WRITE)
4851 *f++ = 'w';
4852 if (flags & SECTION_CODE)
4853 *f++ = 'x';
4854 if (flags & SECTION_SMALL)
4855 *f++ = 's';
4856 if (flags & SECTION_MERGE)
4857 *f++ = 'M';
4858 if (flags & SECTION_STRINGS)
4859 *f++ = 'S';
4860 if (flags & SECTION_TLS)
4861 *f++ = 'T';
4862 if (HAVE_GAS_COMDAT_GROUP && (flags & SECTION_LINKONCE))
4863 *f++ = 'G';
4864 *f = '\0';
4865
4866 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
4867
4868 if (!(flags & SECTION_NOTYPE))
4869 {
4870 const char *type;
4871 const char *format;
4872
4873 if (flags & SECTION_BSS)
4874 type = "nobits";
4875 else
4876 type = "progbits";
4877
4878 format = ",@%s";
4879 #ifdef ASM_COMMENT_START
4880 /* On platforms that use "@" as the assembly comment character,
4881 use "%" instead. */
4882 if (strcmp (ASM_COMMENT_START, "@") == 0)
4883 format = ",%%%s";
4884 #endif
4885 fprintf (asm_out_file, format, type);
4886
4887 if (flags & SECTION_ENTSIZE)
4888 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
4889 if (HAVE_GAS_COMDAT_GROUP && (flags & SECTION_LINKONCE))
4890 fprintf (asm_out_file, ",%s,comdat",
4891 lang_hooks.decls.comdat_group (decl));
4892 }
4893
4894 putc ('\n', asm_out_file);
4895 }
4896
4897 void
4898 default_coff_asm_named_section (const char *name, unsigned int flags,
4899 tree decl ATTRIBUTE_UNUSED)
4900 {
4901 char flagchars[8], *f = flagchars;
4902
4903 if (flags & SECTION_WRITE)
4904 *f++ = 'w';
4905 if (flags & SECTION_CODE)
4906 *f++ = 'x';
4907 *f = '\0';
4908
4909 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
4910 }
4911
4912 void
4913 default_pe_asm_named_section (const char *name, unsigned int flags,
4914 tree decl)
4915 {
4916 default_coff_asm_named_section (name, flags, decl);
4917
4918 if (flags & SECTION_LINKONCE)
4919 {
4920 /* Functions may have been compiled at various levels of
4921 optimization so we can't use `same_size' here.
4922 Instead, have the linker pick one. */
4923 fprintf (asm_out_file, "\t.linkonce %s\n",
4924 (flags & SECTION_CODE ? "discard" : "same_size"));
4925 }
4926 }
4927 \f
4928 /* The lame default section selector. */
4929
4930 void
4931 default_select_section (tree decl, int reloc,
4932 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
4933 {
4934 bool readonly = false;
4935
4936 if (DECL_P (decl))
4937 {
4938 if (decl_readonly_section (decl, reloc))
4939 readonly = true;
4940 }
4941 else if (TREE_CODE (decl) == CONSTRUCTOR)
4942 {
4943 if (! ((flag_pic && reloc)
4944 || !TREE_READONLY (decl)
4945 || TREE_SIDE_EFFECTS (decl)
4946 || !TREE_CONSTANT (decl)))
4947 readonly = true;
4948 }
4949 else if (TREE_CODE (decl) == STRING_CST)
4950 readonly = true;
4951 else if (! (flag_pic && reloc))
4952 readonly = true;
4953
4954 if (readonly)
4955 readonly_data_section ();
4956 else
4957 data_section ();
4958 }
4959
4960 /* A helper function for default_elf_select_section and
4961 default_elf_unique_section. Categorizes the DECL. */
4962
4963 enum section_category
4964 {
4965 SECCAT_TEXT,
4966
4967 SECCAT_RODATA,
4968 SECCAT_RODATA_MERGE_STR,
4969 SECCAT_RODATA_MERGE_STR_INIT,
4970 SECCAT_RODATA_MERGE_CONST,
4971 SECCAT_SRODATA,
4972
4973 SECCAT_DATA,
4974
4975 /* To optimize loading of shared programs, define following subsections
4976 of data section:
4977 _REL Contains data that has relocations, so they get grouped
4978 together and dynamic linker will visit fewer pages in memory.
4979 _RO Contains data that is otherwise read-only. This is useful
4980 with prelinking as most relocations won't be dynamically
4981 linked and thus stay read only.
4982 _LOCAL Marks data containing relocations only to local objects.
4983 These relocations will get fully resolved by prelinking. */
4984 SECCAT_DATA_REL,
4985 SECCAT_DATA_REL_LOCAL,
4986 SECCAT_DATA_REL_RO,
4987 SECCAT_DATA_REL_RO_LOCAL,
4988
4989 SECCAT_SDATA,
4990 SECCAT_TDATA,
4991
4992 SECCAT_BSS,
4993 SECCAT_SBSS,
4994 SECCAT_TBSS
4995 };
4996
4997 static enum section_category
4998 categorize_decl_for_section (tree, int, int);
4999
5000 static enum section_category
5001 categorize_decl_for_section (tree decl, int reloc, int shlib)
5002 {
5003 enum section_category ret;
5004
5005 if (TREE_CODE (decl) == FUNCTION_DECL)
5006 return SECCAT_TEXT;
5007 else if (TREE_CODE (decl) == STRING_CST)
5008 {
5009 if (flag_mudflap) /* or !flag_merge_constants */
5010 return SECCAT_RODATA;
5011 else
5012 return SECCAT_RODATA_MERGE_STR;
5013 }
5014 else if (TREE_CODE (decl) == VAR_DECL)
5015 {
5016 if (DECL_INITIAL (decl) == NULL
5017 || DECL_INITIAL (decl) == error_mark_node
5018 || (flag_zero_initialized_in_bss
5019 /* Leave constant zeroes in .rodata so they can be shared. */
5020 && !TREE_READONLY (decl)
5021 && initializer_zerop (DECL_INITIAL (decl))))
5022 ret = SECCAT_BSS;
5023 else if (! TREE_READONLY (decl)
5024 || TREE_SIDE_EFFECTS (decl)
5025 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
5026 {
5027 if (shlib && (reloc & 2))
5028 ret = SECCAT_DATA_REL;
5029 else if (shlib && reloc)
5030 ret = SECCAT_DATA_REL_LOCAL;
5031 else
5032 ret = SECCAT_DATA;
5033 }
5034 else if (shlib && (reloc & 2))
5035 ret = SECCAT_DATA_REL_RO;
5036 else if (shlib && reloc)
5037 ret = SECCAT_DATA_REL_RO_LOCAL;
5038 else if (reloc || flag_merge_constants < 2)
5039 /* C and C++ don't allow different variables to share the same
5040 location. -fmerge-all-constants allows even that (at the
5041 expense of not conforming). */
5042 ret = SECCAT_RODATA;
5043 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
5044 ret = SECCAT_RODATA_MERGE_STR_INIT;
5045 else
5046 ret = SECCAT_RODATA_MERGE_CONST;
5047 }
5048 else if (TREE_CODE (decl) == CONSTRUCTOR)
5049 {
5050 if ((shlib && reloc)
5051 || TREE_SIDE_EFFECTS (decl)
5052 || ! TREE_CONSTANT (decl))
5053 ret = SECCAT_DATA;
5054 else
5055 ret = SECCAT_RODATA;
5056 }
5057 else
5058 ret = SECCAT_RODATA;
5059
5060 /* There are no read-only thread-local sections. */
5061 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl))
5062 {
5063 /* Note that this would be *just* SECCAT_BSS, except that there's
5064 no concept of a read-only thread-local-data section. */
5065 if (ret == SECCAT_BSS
5066 || (flag_zero_initialized_in_bss
5067 && initializer_zerop (DECL_INITIAL (decl))))
5068 ret = SECCAT_TBSS;
5069 else
5070 ret = SECCAT_TDATA;
5071 }
5072
5073 /* If the target uses small data sections, select it. */
5074 else if (targetm.in_small_data_p (decl))
5075 {
5076 if (ret == SECCAT_BSS)
5077 ret = SECCAT_SBSS;
5078 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
5079 ret = SECCAT_SRODATA;
5080 else
5081 ret = SECCAT_SDATA;
5082 }
5083
5084 return ret;
5085 }
5086
5087 bool
5088 decl_readonly_section (tree decl, int reloc)
5089 {
5090 return decl_readonly_section_1 (decl, reloc, flag_pic);
5091 }
5092
5093 bool
5094 decl_readonly_section_1 (tree decl, int reloc, int shlib)
5095 {
5096 switch (categorize_decl_for_section (decl, reloc, shlib))
5097 {
5098 case SECCAT_RODATA:
5099 case SECCAT_RODATA_MERGE_STR:
5100 case SECCAT_RODATA_MERGE_STR_INIT:
5101 case SECCAT_RODATA_MERGE_CONST:
5102 case SECCAT_SRODATA:
5103 return true;
5104 break;
5105 default:
5106 return false;
5107 break;
5108 }
5109 }
5110
5111 /* Select a section based on the above categorization. */
5112
5113 void
5114 default_elf_select_section (tree decl, int reloc,
5115 unsigned HOST_WIDE_INT align)
5116 {
5117 default_elf_select_section_1 (decl, reloc, align, flag_pic);
5118 }
5119
5120 void
5121 default_elf_select_section_1 (tree decl, int reloc,
5122 unsigned HOST_WIDE_INT align, int shlib)
5123 {
5124 const char *sname;
5125 switch (categorize_decl_for_section (decl, reloc, shlib))
5126 {
5127 case SECCAT_TEXT:
5128 /* We're not supposed to be called on FUNCTION_DECLs. */
5129 gcc_unreachable ();
5130 case SECCAT_RODATA:
5131 readonly_data_section ();
5132 return;
5133 case SECCAT_RODATA_MERGE_STR:
5134 mergeable_string_section (decl, align, 0);
5135 return;
5136 case SECCAT_RODATA_MERGE_STR_INIT:
5137 mergeable_string_section (DECL_INITIAL (decl), align, 0);
5138 return;
5139 case SECCAT_RODATA_MERGE_CONST:
5140 mergeable_constant_section (DECL_MODE (decl), align, 0);
5141 return;
5142 case SECCAT_SRODATA:
5143 sname = ".sdata2";
5144 break;
5145 case SECCAT_DATA:
5146 data_section ();
5147 return;
5148 case SECCAT_DATA_REL:
5149 sname = ".data.rel";
5150 break;
5151 case SECCAT_DATA_REL_LOCAL:
5152 sname = ".data.rel.local";
5153 break;
5154 case SECCAT_DATA_REL_RO:
5155 sname = ".data.rel.ro";
5156 break;
5157 case SECCAT_DATA_REL_RO_LOCAL:
5158 sname = ".data.rel.ro.local";
5159 break;
5160 case SECCAT_SDATA:
5161 sname = ".sdata";
5162 break;
5163 case SECCAT_TDATA:
5164 sname = ".tdata";
5165 break;
5166 case SECCAT_BSS:
5167 #ifdef BSS_SECTION_ASM_OP
5168 bss_section ();
5169 return;
5170 #else
5171 sname = ".bss";
5172 break;
5173 #endif
5174 case SECCAT_SBSS:
5175 sname = ".sbss";
5176 break;
5177 case SECCAT_TBSS:
5178 sname = ".tbss";
5179 break;
5180 default:
5181 gcc_unreachable ();
5182 }
5183
5184 if (!DECL_P (decl))
5185 decl = NULL_TREE;
5186 named_section (decl, sname, reloc);
5187 }
5188
5189 /* Construct a unique section name based on the decl name and the
5190 categorization performed above. */
5191
5192 void
5193 default_unique_section (tree decl, int reloc)
5194 {
5195 default_unique_section_1 (decl, reloc, flag_pic);
5196 }
5197
5198 void
5199 default_unique_section_1 (tree decl, int reloc, int shlib)
5200 {
5201 bool one_only = DECL_ONE_ONLY (decl);
5202 const char *prefix, *name;
5203 size_t nlen, plen;
5204 char *string;
5205
5206 switch (categorize_decl_for_section (decl, reloc, shlib))
5207 {
5208 case SECCAT_TEXT:
5209 prefix = one_only ? ".gnu.linkonce.t." : ".text.";
5210 break;
5211 case SECCAT_RODATA:
5212 case SECCAT_RODATA_MERGE_STR:
5213 case SECCAT_RODATA_MERGE_STR_INIT:
5214 case SECCAT_RODATA_MERGE_CONST:
5215 prefix = one_only ? ".gnu.linkonce.r." : ".rodata.";
5216 break;
5217 case SECCAT_SRODATA:
5218 prefix = one_only ? ".gnu.linkonce.s2." : ".sdata2.";
5219 break;
5220 case SECCAT_DATA:
5221 case SECCAT_DATA_REL:
5222 case SECCAT_DATA_REL_LOCAL:
5223 case SECCAT_DATA_REL_RO:
5224 case SECCAT_DATA_REL_RO_LOCAL:
5225 prefix = one_only ? ".gnu.linkonce.d." : ".data.";
5226 break;
5227 case SECCAT_SDATA:
5228 prefix = one_only ? ".gnu.linkonce.s." : ".sdata.";
5229 break;
5230 case SECCAT_BSS:
5231 prefix = one_only ? ".gnu.linkonce.b." : ".bss.";
5232 break;
5233 case SECCAT_SBSS:
5234 prefix = one_only ? ".gnu.linkonce.sb." : ".sbss.";
5235 break;
5236 case SECCAT_TDATA:
5237 prefix = one_only ? ".gnu.linkonce.td." : ".tdata.";
5238 break;
5239 case SECCAT_TBSS:
5240 prefix = one_only ? ".gnu.linkonce.tb." : ".tbss.";
5241 break;
5242 default:
5243 gcc_unreachable ();
5244 }
5245 plen = strlen (prefix);
5246
5247 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5248 name = targetm.strip_name_encoding (name);
5249 nlen = strlen (name);
5250
5251 string = alloca (nlen + plen + 1);
5252 memcpy (string, prefix, plen);
5253 memcpy (string + plen, name, nlen + 1);
5254
5255 DECL_SECTION_NAME (decl) = build_string (nlen + plen, string);
5256 }
5257
5258 void
5259 default_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
5260 rtx x,
5261 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
5262 {
5263 if (flag_pic)
5264 switch (GET_CODE (x))
5265 {
5266 case CONST:
5267 case SYMBOL_REF:
5268 case LABEL_REF:
5269 data_section ();
5270 return;
5271
5272 default:
5273 break;
5274 }
5275
5276 readonly_data_section ();
5277 }
5278
5279 void
5280 default_elf_select_rtx_section (enum machine_mode mode, rtx x,
5281 unsigned HOST_WIDE_INT align)
5282 {
5283 /* ??? Handle small data here somehow. */
5284
5285 if (flag_pic)
5286 switch (GET_CODE (x))
5287 {
5288 case CONST:
5289 case SYMBOL_REF:
5290 named_section (NULL_TREE, ".data.rel.ro", 3);
5291 return;
5292
5293 case LABEL_REF:
5294 named_section (NULL_TREE, ".data.rel.ro.local", 1);
5295 return;
5296
5297 default:
5298 break;
5299 }
5300
5301 mergeable_constant_section (mode, align, 0);
5302 }
5303
5304 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
5305
5306 void
5307 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
5308 {
5309 rtx symbol;
5310 int flags;
5311
5312 /* Careful not to prod global register variables. */
5313 if (!MEM_P (rtl))
5314 return;
5315 symbol = XEXP (rtl, 0);
5316 if (GET_CODE (symbol) != SYMBOL_REF)
5317 return;
5318
5319 flags = 0;
5320 if (TREE_CODE (decl) == FUNCTION_DECL)
5321 flags |= SYMBOL_FLAG_FUNCTION;
5322 if (targetm.binds_local_p (decl))
5323 flags |= SYMBOL_FLAG_LOCAL;
5324 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl))
5325 flags |= decl_tls_model (decl) << SYMBOL_FLAG_TLS_SHIFT;
5326 else if (targetm.in_small_data_p (decl))
5327 flags |= SYMBOL_FLAG_SMALL;
5328 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
5329 being PUBLIC, the thing *must* be defined in this translation unit.
5330 Prevent this buglet from being propagated into rtl code as well. */
5331 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
5332 flags |= SYMBOL_FLAG_EXTERNAL;
5333
5334 SYMBOL_REF_FLAGS (symbol) = flags;
5335 }
5336
5337 /* By default, we do nothing for encode_section_info, so we need not
5338 do anything but discard the '*' marker. */
5339
5340 const char *
5341 default_strip_name_encoding (const char *str)
5342 {
5343 return str + (*str == '*');
5344 }
5345
5346 /* Assume ELF-ish defaults, since that's pretty much the most liberal
5347 wrt cross-module name binding. */
5348
5349 bool
5350 default_binds_local_p (tree exp)
5351 {
5352 return default_binds_local_p_1 (exp, flag_shlib);
5353 }
5354
5355 bool
5356 default_binds_local_p_1 (tree exp, int shlib)
5357 {
5358 bool local_p;
5359
5360 /* A non-decl is an entry in the constant pool. */
5361 if (!DECL_P (exp))
5362 local_p = true;
5363 /* Static variables are always local. */
5364 else if (! TREE_PUBLIC (exp))
5365 local_p = true;
5366 /* A variable is local if the user explicitly tells us so. */
5367 else if (DECL_VISIBILITY_SPECIFIED (exp) && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
5368 local_p = true;
5369 /* Otherwise, variables defined outside this object may not be local. */
5370 else if (DECL_EXTERNAL (exp))
5371 local_p = false;
5372 /* Linkonce and weak data are never local. */
5373 else if (DECL_ONE_ONLY (exp) || DECL_WEAK (exp))
5374 local_p = false;
5375 /* If none of the above and visibility is not default, make local. */
5376 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
5377 local_p = true;
5378 /* If PIC, then assume that any global name can be overridden by
5379 symbols resolved from other modules. */
5380 else if (shlib)
5381 local_p = false;
5382 /* Uninitialized COMMON variable may be unified with symbols
5383 resolved from other modules. */
5384 else if (DECL_COMMON (exp)
5385 && (DECL_INITIAL (exp) == NULL
5386 || DECL_INITIAL (exp) == error_mark_node))
5387 local_p = false;
5388 /* Otherwise we're left with initialized (or non-common) global data
5389 which is of necessity defined locally. */
5390 else
5391 local_p = true;
5392
5393 return local_p;
5394 }
5395
5396 /* Determine whether or not a pointer mode is valid. Assume defaults
5397 of ptr_mode or Pmode - can be overridden. */
5398 bool
5399 default_valid_pointer_mode (enum machine_mode mode)
5400 {
5401 return (mode == ptr_mode || mode == Pmode);
5402 }
5403
5404 /* Default function to output code that will globalize a label. A
5405 target must define GLOBAL_ASM_OP or provide its own function to
5406 globalize a label. */
5407 #ifdef GLOBAL_ASM_OP
5408 void
5409 default_globalize_label (FILE * stream, const char *name)
5410 {
5411 fputs (GLOBAL_ASM_OP, stream);
5412 assemble_name (stream, name);
5413 putc ('\n', stream);
5414 }
5415 #endif /* GLOBAL_ASM_OP */
5416
5417 /* Default function to output a label for unwind information. The
5418 default is to do nothing. A target that needs nonlocal labels for
5419 unwind information must provide its own function to do this. */
5420 void
5421 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
5422 tree decl ATTRIBUTE_UNUSED,
5423 int for_eh ATTRIBUTE_UNUSED,
5424 int empty ATTRIBUTE_UNUSED)
5425 {
5426 }
5427
5428 /* This is how to output an internal numbered label where PREFIX is
5429 the class of label and LABELNO is the number within the class. */
5430
5431 void
5432 default_internal_label (FILE *stream, const char *prefix,
5433 unsigned long labelno)
5434 {
5435 char *const buf = alloca (40 + strlen (prefix));
5436 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
5437 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
5438 }
5439
5440 /* This is the default behavior at the beginning of a file. It's
5441 controlled by two other target-hook toggles. */
5442 void
5443 default_file_start (void)
5444 {
5445 if (targetm.file_start_app_off && !flag_verbose_asm)
5446 fputs (ASM_APP_OFF, asm_out_file);
5447
5448 if (targetm.file_start_file_directive)
5449 output_file_directive (asm_out_file, main_input_filename);
5450 }
5451
5452 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
5453 which emits a special section directive used to indicate whether or
5454 not this object file needs an executable stack. This is primarily
5455 a GNU extension to ELF but could be used on other targets. */
5456
5457 int trampolines_created;
5458
5459 void
5460 file_end_indicate_exec_stack (void)
5461 {
5462 unsigned int flags = SECTION_DEBUG;
5463 if (trampolines_created)
5464 flags |= SECTION_CODE;
5465
5466 named_section_flags (".note.GNU-stack", flags);
5467 }
5468
5469 #include "gt-varasm.h"