usage.adb: Change "pragma inline" to "pragma Inline" in information and error messages
[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 Free Software Foundation, Inc.
4
5 This file is part of GCC.
6
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
10 version.
11
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 for more details.
16
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
20 02111-1307, USA. */
21
22
23 /* This file handles generation of all the assembler code
24 *except* the instructions of a function.
25 This includes declarations of variables and their initial values.
26
27 We also output the assembler code for constants stored in memory
28 and are responsible for combining constants with the same value. */
29
30 #include "config.h"
31 #include "system.h"
32 #include "coretypes.h"
33 #include "tm.h"
34 #include "rtl.h"
35 #include "tree.h"
36 #include "flags.h"
37 #include "function.h"
38 #include "expr.h"
39 #include "hard-reg-set.h"
40 #include "regs.h"
41 #include "real.h"
42 #include "output.h"
43 #include "toplev.h"
44 #include "hashtab.h"
45 #include "c-pragma.h"
46 #include "ggc.h"
47 #include "langhooks.h"
48 #include "tm_p.h"
49 #include "debug.h"
50 #include "target.h"
51 #include "tree-mudflap.h"
52 #include "cgraph.h"
53 #include "cfglayout.h"
54
55 #ifdef XCOFF_DEBUGGING_INFO
56 #include "xcoffout.h" /* Needed for external data
57 declarations for e.g. AIX 4.x. */
58 #endif
59
60 #ifndef ASM_STABS_OP
61 #define ASM_STABS_OP "\t.stabs\t"
62 #endif
63
64 /* The (assembler) name of the first globally-visible object output. */
65 const char *first_global_object_name;
66 const char *weak_global_object_name;
67
68 struct addr_const;
69 struct constant_descriptor_rtx;
70 struct rtx_constant_pool;
71
72 struct varasm_status GTY(())
73 {
74 /* If we're using a per-function constant pool, this is it. */
75 struct rtx_constant_pool *pool;
76
77 /* Number of tree-constants deferred during the expansion of this
78 function. */
79 unsigned int deferred_constants;
80 };
81
82 #define n_deferred_constants (cfun->varasm->deferred_constants)
83
84 /* Number for making the label on the next
85 constant that is stored in memory. */
86
87 static GTY(()) int const_labelno;
88
89 /* Carry information from ASM_DECLARE_OBJECT_NAME
90 to ASM_FINISH_DECLARE_OBJECT. */
91
92 int size_directive_output;
93
94 /* The last decl for which assemble_variable was called,
95 if it did ASM_DECLARE_OBJECT_NAME.
96 If the last call to assemble_variable didn't do that,
97 this holds 0. */
98
99 tree last_assemble_variable_decl;
100
101 /* The following global variable indicates if the section label for the
102 "cold" section of code has been output yet to the assembler. The
103 label is useful when running gdb. This is part of the optimization that
104 partitions hot and cold basic blocks into separate sections of the .o
105 file. */
106
107 static bool unlikely_section_label_printed = false;
108
109 /* The following global variable indicates the label name to be put at
110 the start of the first cold section within each function, when
111 partitioning basic blocks into hot and cold sections. */
112
113 static char *unlikely_section_label = NULL;
114
115 /* The following global variable indicates the section name to be used
116 for the current cold section, when partitioning hot and cold basic
117 blocks into separate sections. */
118
119 static char *unlikely_text_section_name = NULL;
120
121 /* We give all constants their own alias set. Perhaps redundant with
122 MEM_READONLY_P, but pre-dates it. */
123
124 static HOST_WIDE_INT const_alias_set;
125
126 static const char *strip_reg_name (const char *);
127 static int contains_pointers_p (tree);
128 #ifdef ASM_OUTPUT_EXTERNAL
129 static bool incorporeal_function_p (tree);
130 #endif
131 static void decode_addr_const (tree, struct addr_const *);
132 static hashval_t const_desc_hash (const void *);
133 static int const_desc_eq (const void *, const void *);
134 static hashval_t const_hash_1 (const tree);
135 static int compare_constant (const tree, const tree);
136 static tree copy_constant (tree);
137 static void output_constant_def_contents (rtx);
138 static void output_addressed_constants (tree);
139 static unsigned HOST_WIDE_INT array_size_for_constructor (tree);
140 static unsigned min_align (unsigned, unsigned);
141 static void output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int);
142 static void globalize_decl (tree);
143 static void maybe_assemble_visibility (tree);
144 static int in_named_entry_eq (const void *, const void *);
145 static hashval_t in_named_entry_hash (const void *);
146 #ifdef BSS_SECTION_ASM_OP
147 #ifdef ASM_OUTPUT_BSS
148 static void asm_output_bss (FILE *, tree, const char *,
149 unsigned HOST_WIDE_INT, unsigned HOST_WIDE_INT);
150 #endif
151 #ifdef ASM_OUTPUT_ALIGNED_BSS
152 static void asm_output_aligned_bss (FILE *, tree, const char *,
153 unsigned HOST_WIDE_INT, int)
154 ATTRIBUTE_UNUSED;
155 #endif
156 #endif /* BSS_SECTION_ASM_OP */
157 static bool asm_emit_uninitialised (tree, const char*,
158 unsigned HOST_WIDE_INT,
159 unsigned HOST_WIDE_INT);
160 static void mark_weak (tree);
161 \f
162 enum in_section { no_section, in_text, in_unlikely_executed_text, in_data,
163 in_named
164 #ifdef BSS_SECTION_ASM_OP
165 , in_bss
166 #endif
167 #ifdef CTORS_SECTION_ASM_OP
168 , in_ctors
169 #endif
170 #ifdef DTORS_SECTION_ASM_OP
171 , in_dtors
172 #endif
173 #ifdef READONLY_DATA_SECTION_ASM_OP
174 , in_readonly_data
175 #endif
176 #ifdef EXTRA_SECTIONS
177 , EXTRA_SECTIONS
178 #endif
179 };
180 static GTY(()) enum in_section in_section = no_section;
181
182 /* Return a nonzero value if DECL has a section attribute. */
183 #ifndef IN_NAMED_SECTION
184 #define IN_NAMED_SECTION(DECL) \
185 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \
186 && DECL_SECTION_NAME (DECL) != NULL_TREE)
187 #endif
188
189 /* Text of section name when in_section == in_named. */
190 static GTY(()) const char *in_named_name;
191
192 /* Hash table of flags that have been used for a particular named section. */
193
194 struct in_named_entry GTY(())
195 {
196 const char *name;
197 unsigned int flags;
198 bool declared;
199 };
200
201 static GTY((param_is (struct in_named_entry))) htab_t in_named_htab;
202
203 /* Define functions like text_section for any extra sections. */
204 #ifdef EXTRA_SECTION_FUNCTIONS
205 EXTRA_SECTION_FUNCTIONS
206 #endif
207
208 /* Tell assembler to switch to text section. */
209
210 void
211 text_section (void)
212 {
213 if (in_section != in_text)
214 {
215 in_section = in_text;
216 fprintf (asm_out_file, "%s\n", TEXT_SECTION_ASM_OP);
217 }
218 }
219
220 /* Tell assembler to switch to unlikely-to-be-executed text section. */
221
222 void
223 unlikely_text_section (void)
224 {
225 const char *name;
226 int len;
227
228 if (! unlikely_text_section_name)
229 {
230 if (DECL_SECTION_NAME (current_function_decl)
231 && (strcmp (TREE_STRING_POINTER (DECL_SECTION_NAME
232 (current_function_decl)),
233 HOT_TEXT_SECTION_NAME) != 0)
234 && (strcmp (TREE_STRING_POINTER (DECL_SECTION_NAME
235 (current_function_decl)),
236 UNLIKELY_EXECUTED_TEXT_SECTION_NAME) != 0))
237 {
238 name = TREE_STRING_POINTER (DECL_SECTION_NAME
239 (current_function_decl));
240 len = strlen (name);
241 unlikely_text_section_name = xmalloc ((len + 10) * sizeof (char));
242 strcpy (unlikely_text_section_name, name);
243 strcat (unlikely_text_section_name, "_unlikely");
244 }
245 else
246 {
247 len = strlen (UNLIKELY_EXECUTED_TEXT_SECTION_NAME);
248 unlikely_text_section_name = xmalloc (len+1 * sizeof (char));
249 strcpy (unlikely_text_section_name,
250 UNLIKELY_EXECUTED_TEXT_SECTION_NAME);
251 }
252 }
253
254 if ((in_section != in_unlikely_executed_text)
255 && (in_section != in_named
256 || strcmp (in_named_name, unlikely_text_section_name) != 0))
257 {
258 named_section (NULL_TREE, unlikely_text_section_name, 0);
259 in_section = in_unlikely_executed_text;
260
261 if (!unlikely_section_label_printed)
262 {
263 ASM_OUTPUT_LABEL (asm_out_file, unlikely_section_label);
264 unlikely_section_label_printed = true;
265 }
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 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 if (! set_named_section_flags (name, flags))
430 abort ();
431
432 targetm.asm_out.named_section (name, flags, decl);
433
434 if (flags & SECTION_FORGET)
435 in_section = no_section;
436 else
437 {
438 in_named_name = ggc_strdup (name);
439 in_section = in_named;
440 }
441 }
442 }
443
444 /* Tell assembler to change to section NAME for DECL.
445 If DECL is NULL, just switch to section NAME.
446 If NAME is NULL, get the name from DECL.
447 If RELOC is 1, the initializer for DECL contains relocs. */
448
449 void
450 named_section (tree decl, const char *name, int reloc)
451 {
452 unsigned int flags;
453
454 if (decl != NULL_TREE && !DECL_P (decl))
455 abort ();
456 if (name == NULL)
457 name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
458
459 if (strcmp (name, UNLIKELY_EXECUTED_TEXT_SECTION_NAME) == 0
460 && !unlikely_text_section_name)
461 {
462 unlikely_text_section_name = xmalloc
463 (strlen (UNLIKELY_EXECUTED_TEXT_SECTION_NAME) + 1
464 * sizeof (char));
465 strcpy (unlikely_text_section_name,
466 UNLIKELY_EXECUTED_TEXT_SECTION_NAME);
467 }
468
469 flags = targetm.section_type_flags (decl, name, reloc);
470
471 /* Sanity check user variables for flag changes. Non-user
472 section flag changes will abort in named_section_flags.
473 However, don't complain if SECTION_OVERRIDE is set.
474 We trust that the setter knows that it is safe to ignore
475 the default flags for this decl. */
476 if (decl && ! set_named_section_flags (name, flags))
477 {
478 flags = get_named_section_flags (name);
479 if ((flags & SECTION_OVERRIDE) == 0)
480 error ("%J%D causes a section type conflict", decl, decl);
481 }
482
483 named_section_real (name, flags, decl);
484 }
485
486 /* If required, set DECL_SECTION_NAME to a unique name. */
487
488 void
489 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
490 int flag_function_or_data_sections)
491 {
492 if (DECL_SECTION_NAME (decl) == NULL_TREE
493 && targetm.have_named_sections
494 && (flag_function_or_data_sections
495 || DECL_ONE_ONLY (decl)))
496 targetm.asm_out.unique_section (decl, reloc);
497 }
498
499 #ifdef BSS_SECTION_ASM_OP
500
501 /* Tell the assembler to switch to the bss section. */
502
503 void
504 bss_section (void)
505 {
506 if (in_section != in_bss)
507 {
508 fprintf (asm_out_file, "%s\n", BSS_SECTION_ASM_OP);
509 in_section = in_bss;
510 }
511 }
512
513 #ifdef ASM_OUTPUT_BSS
514
515 /* Utility function for ASM_OUTPUT_BSS for targets to use if
516 they don't support alignments in .bss.
517 ??? It is believed that this function will work in most cases so such
518 support is localized here. */
519
520 static void
521 asm_output_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
522 const char *name,
523 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
524 unsigned HOST_WIDE_INT rounded)
525 {
526 targetm.asm_out.globalize_label (file, name);
527 bss_section ();
528 #ifdef ASM_DECLARE_OBJECT_NAME
529 last_assemble_variable_decl = decl;
530 ASM_DECLARE_OBJECT_NAME (file, name, decl);
531 #else
532 /* Standard thing is just output label for the object. */
533 ASM_OUTPUT_LABEL (file, name);
534 #endif /* ASM_DECLARE_OBJECT_NAME */
535 ASM_OUTPUT_SKIP (file, rounded ? rounded : 1);
536 }
537
538 #endif
539
540 #ifdef ASM_OUTPUT_ALIGNED_BSS
541
542 /* Utility function for targets to use in implementing
543 ASM_OUTPUT_ALIGNED_BSS.
544 ??? It is believed that this function will work in most cases so such
545 support is localized here. */
546
547 static void
548 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
549 const char *name, unsigned HOST_WIDE_INT size,
550 int align)
551 {
552 bss_section ();
553 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
554 #ifdef ASM_DECLARE_OBJECT_NAME
555 last_assemble_variable_decl = decl;
556 ASM_DECLARE_OBJECT_NAME (file, name, decl);
557 #else
558 /* Standard thing is just output label for the object. */
559 ASM_OUTPUT_LABEL (file, name);
560 #endif /* ASM_DECLARE_OBJECT_NAME */
561 ASM_OUTPUT_SKIP (file, size ? size : 1);
562 }
563
564 #endif
565
566 #endif /* BSS_SECTION_ASM_OP */
567
568 /* Switch to the section for function DECL.
569
570 If DECL is NULL_TREE, switch to the text section.
571 ??? It's not clear that we will ever be passed NULL_TREE, but it's
572 safer to handle it. */
573
574 void
575 function_section (tree decl)
576 {
577 if (scan_ahead_for_unlikely_executed_note (get_insns()))
578 unlikely_text_section ();
579 else if (decl != NULL_TREE
580 && DECL_SECTION_NAME (decl) != NULL_TREE)
581 named_section (decl, (char *) 0, 0);
582 else
583 text_section ();
584 }
585
586 /* Switch to read-only data section associated with function DECL. */
587
588 void
589 default_function_rodata_section (tree decl)
590 {
591 if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
592 {
593 const char *name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
594
595 /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo. */
596 if (DECL_ONE_ONLY (decl) && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
597 {
598 size_t len = strlen (name) + 1;
599 char *rname = alloca (len);
600
601 memcpy (rname, name, len);
602 rname[14] = 'r';
603 named_section_real (rname, SECTION_LINKONCE, decl);
604 return;
605 }
606 /* For .text.foo we want to use .rodata.foo. */
607 else if (flag_function_sections && flag_data_sections
608 && strncmp (name, ".text.", 6) == 0)
609 {
610 size_t len = strlen (name) + 1;
611 char *rname = alloca (len + 2);
612
613 memcpy (rname, ".rodata", 7);
614 memcpy (rname + 7, name + 5, len - 5);
615 named_section_flags (rname, 0);
616 return;
617 }
618 }
619
620 readonly_data_section ();
621 }
622
623 /* Switch to read-only data section associated with function DECL
624 for targets where that section should be always the single
625 readonly data section. */
626
627 void
628 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
629 {
630 readonly_data_section ();
631 }
632
633 /* Switch to section for variable DECL. RELOC is the same as the
634 argument to SELECT_SECTION. */
635
636 void
637 variable_section (tree decl, int reloc)
638 {
639 if (IN_NAMED_SECTION (decl))
640 named_section (decl, NULL, reloc);
641 else
642 targetm.asm_out.select_section (decl, reloc, DECL_ALIGN (decl));
643 }
644
645 /* Tell assembler to switch to the section for string merging. */
646
647 void
648 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
649 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
650 unsigned int flags ATTRIBUTE_UNUSED)
651 {
652 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
653 && TREE_CODE (decl) == STRING_CST
654 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
655 && align <= 256
656 && TREE_STRING_LENGTH (decl) >= int_size_in_bytes (TREE_TYPE (decl)))
657 {
658 enum machine_mode mode;
659 unsigned int modesize;
660 const char *str;
661 int i, j, len, unit;
662 char name[30];
663
664 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
665 modesize = GET_MODE_BITSIZE (mode);
666 if (modesize >= 8 && modesize <= 256
667 && (modesize & (modesize - 1)) == 0)
668 {
669 if (align < modesize)
670 align = modesize;
671
672 str = TREE_STRING_POINTER (decl);
673 len = TREE_STRING_LENGTH (decl);
674 unit = GET_MODE_SIZE (mode);
675
676 /* Check for embedded NUL characters. */
677 for (i = 0; i < len; i += unit)
678 {
679 for (j = 0; j < unit; j++)
680 if (str[i + j] != '\0')
681 break;
682 if (j == unit)
683 break;
684 }
685 if (i == len - unit)
686 {
687 sprintf (name, ".rodata.str%d.%d", modesize / 8,
688 (int) (align / 8));
689 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
690 if (!i && modesize < align)
691 {
692 /* A "" string with requested alignment greater than
693 character size might cause a problem:
694 if some other string required even bigger
695 alignment than "", then linker might think the
696 "" is just part of padding after some other string
697 and not put it into the hash table initially.
698 But this means "" could have smaller alignment
699 than requested. */
700 #ifdef ASM_OUTPUT_SECTION_START
701 named_section_flags (name, flags);
702 ASM_OUTPUT_SECTION_START (asm_out_file);
703 #else
704 readonly_data_section ();
705 #endif
706 return;
707 }
708
709 named_section_flags (name, flags);
710 return;
711 }
712 }
713 }
714
715 readonly_data_section ();
716 }
717
718 /* Tell assembler to switch to the section for constant merging. */
719
720 void
721 mergeable_constant_section (enum machine_mode mode ATTRIBUTE_UNUSED,
722 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
723 unsigned int flags ATTRIBUTE_UNUSED)
724 {
725 unsigned int modesize = GET_MODE_BITSIZE (mode);
726
727 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
728 && mode != VOIDmode
729 && mode != BLKmode
730 && modesize <= align
731 && align >= 8
732 && align <= 256
733 && (align & (align - 1)) == 0)
734 {
735 char name[24];
736
737 sprintf (name, ".rodata.cst%d", (int) (align / 8));
738 flags |= (align / 8) | SECTION_MERGE;
739 named_section_flags (name, flags);
740 return;
741 }
742
743 readonly_data_section ();
744 }
745 \f
746 /* Given NAME, a putative register name, discard any customary prefixes. */
747
748 static const char *
749 strip_reg_name (const char *name)
750 {
751 #ifdef REGISTER_PREFIX
752 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
753 name += strlen (REGISTER_PREFIX);
754 #endif
755 if (name[0] == '%' || name[0] == '#')
756 name++;
757 return name;
758 }
759 \f
760 /* The user has asked for a DECL to have a particular name. Set (or
761 change) it in such a way that we don't prefix an underscore to
762 it. */
763 void
764 set_user_assembler_name (tree decl, const char *name)
765 {
766 char *starred = alloca (strlen (name) + 2);
767 starred[0] = '*';
768 strcpy (starred + 1, name);
769 change_decl_assembler_name (decl, get_identifier (starred));
770 SET_DECL_RTL (decl, NULL_RTX);
771 }
772 \f
773 /* Decode an `asm' spec for a declaration as a register name.
774 Return the register number, or -1 if nothing specified,
775 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
776 or -3 if ASMSPEC is `cc' and is not recognized,
777 or -4 if ASMSPEC is `memory' and is not recognized.
778 Accept an exact spelling or a decimal number.
779 Prefixes such as % are optional. */
780
781 int
782 decode_reg_name (const char *asmspec)
783 {
784 if (asmspec != 0 && strlen (asmspec) != 0)
785 {
786 int i;
787
788 /* Get rid of confusing prefixes. */
789 asmspec = strip_reg_name (asmspec);
790
791 /* Allow a decimal number as a "register name". */
792 for (i = strlen (asmspec) - 1; i >= 0; i--)
793 if (! ISDIGIT (asmspec[i]))
794 break;
795 if (asmspec[0] != 0 && i < 0)
796 {
797 i = atoi (asmspec);
798 if (i < FIRST_PSEUDO_REGISTER && i >= 0)
799 return i;
800 else
801 return -2;
802 }
803
804 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
805 if (reg_names[i][0]
806 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
807 return i;
808
809 #ifdef ADDITIONAL_REGISTER_NAMES
810 {
811 static const struct { const char *const name; const int number; } table[]
812 = ADDITIONAL_REGISTER_NAMES;
813
814 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
815 if (! strcmp (asmspec, table[i].name))
816 return table[i].number;
817 }
818 #endif /* ADDITIONAL_REGISTER_NAMES */
819
820 if (!strcmp (asmspec, "memory"))
821 return -4;
822
823 if (!strcmp (asmspec, "cc"))
824 return -3;
825
826 return -2;
827 }
828
829 return -1;
830 }
831 \f
832 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
833 have static storage duration. In other words, it should not be an
834 automatic variable, including PARM_DECLs.
835
836 There is, however, one exception: this function handles variables
837 explicitly placed in a particular register by the user.
838
839 This is never called for PARM_DECL nodes. */
840
841 void
842 make_decl_rtl (tree decl)
843 {
844 const char *name = 0;
845 int reg_number;
846 rtx x;
847
848 /* Check that we are not being given an automatic variable. */
849 /* A weak alias has TREE_PUBLIC set but not the other bits. */
850 if (TREE_CODE (decl) == PARM_DECL
851 || TREE_CODE (decl) == RESULT_DECL
852 || (TREE_CODE (decl) == VAR_DECL
853 && !TREE_STATIC (decl)
854 && !TREE_PUBLIC (decl)
855 && !DECL_EXTERNAL (decl)
856 && !DECL_REGISTER (decl)))
857 abort ();
858 /* And that we were not given a type or a label. */
859 else if (TREE_CODE (decl) == TYPE_DECL
860 || TREE_CODE (decl) == LABEL_DECL)
861 abort ();
862
863 /* For a duplicate declaration, we can be called twice on the
864 same DECL node. Don't discard the RTL already made. */
865 if (DECL_RTL_SET_P (decl))
866 {
867 /* If the old RTL had the wrong mode, fix the mode. */
868 if (GET_MODE (DECL_RTL (decl)) != DECL_MODE (decl))
869 SET_DECL_RTL (decl, adjust_address_nv (DECL_RTL (decl),
870 DECL_MODE (decl), 0));
871
872 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
873 return;
874
875 /* ??? Another way to do this would be to maintain a hashed
876 table of such critters. Instead of adding stuff to a DECL
877 to give certain attributes to it, we could use an external
878 hash map from DECL to set of attributes. */
879
880 /* Let the target reassign the RTL if it wants.
881 This is necessary, for example, when one machine specific
882 decl attribute overrides another. */
883 targetm.encode_section_info (decl, DECL_RTL (decl), false);
884
885 /* Make this function static known to the mudflap runtime. */
886 if (flag_mudflap && TREE_CODE (decl) == VAR_DECL)
887 mudflap_enqueue_decl (decl);
888
889 return;
890 }
891
892 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
893
894 reg_number = decode_reg_name (name);
895
896 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
897 {
898 /* First detect errors in declaring global registers. */
899 if (reg_number == -1)
900 error ("%Jregister name not specified for %qD", decl, decl);
901 else if (reg_number < 0)
902 error ("%Jinvalid register name for %qD", decl, decl);
903 else if (TYPE_MODE (TREE_TYPE (decl)) == BLKmode)
904 error ("%Jdata type of %qD isn%'t suitable for a register",
905 decl, decl);
906 else if (! HARD_REGNO_MODE_OK (reg_number, TYPE_MODE (TREE_TYPE (decl))))
907 error ("%Jregister specified for %qD isn%'t suitable for data type",
908 decl, decl);
909 /* Now handle properly declared static register variables. */
910 else
911 {
912 int nregs;
913
914 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
915 {
916 DECL_INITIAL (decl) = 0;
917 error ("global register variable has initial value");
918 }
919 if (TREE_THIS_VOLATILE (decl))
920 warning ("volatile register variables don%'t "
921 "work as you might wish");
922
923 /* If the user specified one of the eliminables registers here,
924 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
925 confused with that register and be eliminated. This usage is
926 somewhat suspect... */
927
928 SET_DECL_RTL (decl, gen_rtx_raw_REG (DECL_MODE (decl), reg_number));
929 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
930 REG_USERVAR_P (DECL_RTL (decl)) = 1;
931
932 if (TREE_STATIC (decl))
933 {
934 /* Make this register global, so not usable for anything
935 else. */
936 #ifdef ASM_DECLARE_REGISTER_GLOBAL
937 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
938 #endif
939 nregs = hard_regno_nregs[reg_number][DECL_MODE (decl)];
940 while (nregs > 0)
941 globalize_reg (reg_number + --nregs);
942 }
943
944 /* As a register variable, it has no section. */
945 return;
946 }
947 }
948
949 /* Now handle ordinary static variables and functions (in memory).
950 Also handle vars declared register invalidly. */
951
952 if (name[0] == '*' && (reg_number >= 0 || reg_number == -3))
953 error ("%Jregister name given for non-register variable %qD", decl, decl);
954
955 /* Specifying a section attribute on a variable forces it into a
956 non-.bss section, and thus it cannot be common. */
957 if (TREE_CODE (decl) == VAR_DECL
958 && DECL_SECTION_NAME (decl) != NULL_TREE
959 && DECL_INITIAL (decl) == NULL_TREE
960 && DECL_COMMON (decl))
961 DECL_COMMON (decl) = 0;
962
963 /* Variables can't be both common and weak. */
964 if (TREE_CODE (decl) == VAR_DECL && DECL_WEAK (decl))
965 DECL_COMMON (decl) = 0;
966
967 x = gen_rtx_SYMBOL_REF (Pmode, name);
968 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
969 SYMBOL_REF_DECL (x) = decl;
970
971 x = gen_rtx_MEM (DECL_MODE (decl), x);
972 if (TREE_CODE (decl) != FUNCTION_DECL)
973 set_mem_attributes (x, decl, 1);
974 SET_DECL_RTL (decl, x);
975
976 /* Optionally set flags or add text to the name to record information
977 such as that it is a function name.
978 If the name is changed, the macro ASM_OUTPUT_LABELREF
979 will have to know how to strip this information. */
980 targetm.encode_section_info (decl, DECL_RTL (decl), true);
981
982 /* Make this function static known to the mudflap runtime. */
983 if (flag_mudflap && TREE_CODE (decl) == VAR_DECL)
984 mudflap_enqueue_decl (decl);
985 }
986
987 /* Make the rtl for variable VAR be volatile.
988 Use this only for static variables. */
989
990 void
991 make_var_volatile (tree var)
992 {
993 if (!MEM_P (DECL_RTL (var)))
994 abort ();
995
996 MEM_VOLATILE_P (DECL_RTL (var)) = 1;
997 }
998 \f
999 /* Output a string of literal assembler code
1000 for an `asm' keyword used between functions. */
1001
1002 void
1003 assemble_asm (tree string)
1004 {
1005 app_enable ();
1006
1007 if (TREE_CODE (string) == ADDR_EXPR)
1008 string = TREE_OPERAND (string, 0);
1009
1010 fprintf (asm_out_file, "\t%s\n", TREE_STRING_POINTER (string));
1011 }
1012
1013 /* Record an element in the table of global destructors. SYMBOL is
1014 a SYMBOL_REF of the function to be called; PRIORITY is a number
1015 between 0 and MAX_INIT_PRIORITY. */
1016
1017 void
1018 default_stabs_asm_out_destructor (rtx symbol, int priority ATTRIBUTE_UNUSED)
1019 {
1020 /* Tell GNU LD that this is part of the static destructor set.
1021 This will work for any system that uses stabs, most usefully
1022 aout systems. */
1023 fprintf (asm_out_file, "%s\"___DTOR_LIST__\",22,0,0,", ASM_STABS_OP);
1024 assemble_name (asm_out_file, XSTR (symbol, 0));
1025 fputc ('\n', asm_out_file);
1026 }
1027
1028 void
1029 default_named_section_asm_out_destructor (rtx symbol, int priority)
1030 {
1031 const char *section = ".dtors";
1032 char buf[16];
1033
1034 /* ??? This only works reliably with the GNU linker. */
1035 if (priority != DEFAULT_INIT_PRIORITY)
1036 {
1037 sprintf (buf, ".dtors.%.5u",
1038 /* Invert the numbering so the linker puts us in the proper
1039 order; constructors are run from right to left, and the
1040 linker sorts in increasing order. */
1041 MAX_INIT_PRIORITY - priority);
1042 section = buf;
1043 }
1044
1045 named_section_flags (section, SECTION_WRITE);
1046 assemble_align (POINTER_SIZE);
1047 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1048 }
1049
1050 #ifdef DTORS_SECTION_ASM_OP
1051 void
1052 dtors_section (void)
1053 {
1054 if (in_section != in_dtors)
1055 {
1056 in_section = in_dtors;
1057 fputs (DTORS_SECTION_ASM_OP, asm_out_file);
1058 fputc ('\n', asm_out_file);
1059 }
1060 }
1061
1062 void
1063 default_dtor_section_asm_out_destructor (rtx symbol,
1064 int priority ATTRIBUTE_UNUSED)
1065 {
1066 dtors_section ();
1067 assemble_align (POINTER_SIZE);
1068 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1069 }
1070 #endif
1071
1072 /* Likewise for global constructors. */
1073
1074 void
1075 default_stabs_asm_out_constructor (rtx symbol, int priority ATTRIBUTE_UNUSED)
1076 {
1077 /* Tell GNU LD that this is part of the static destructor set.
1078 This will work for any system that uses stabs, most usefully
1079 aout systems. */
1080 fprintf (asm_out_file, "%s\"___CTOR_LIST__\",22,0,0,", ASM_STABS_OP);
1081 assemble_name (asm_out_file, XSTR (symbol, 0));
1082 fputc ('\n', asm_out_file);
1083 }
1084
1085 void
1086 default_named_section_asm_out_constructor (rtx symbol, int priority)
1087 {
1088 const char *section = ".ctors";
1089 char buf[16];
1090
1091 /* ??? This only works reliably with the GNU linker. */
1092 if (priority != DEFAULT_INIT_PRIORITY)
1093 {
1094 sprintf (buf, ".ctors.%.5u",
1095 /* Invert the numbering so the linker puts us in the proper
1096 order; constructors are run from right to left, and the
1097 linker sorts in increasing order. */
1098 MAX_INIT_PRIORITY - priority);
1099 section = buf;
1100 }
1101
1102 named_section_flags (section, SECTION_WRITE);
1103 assemble_align (POINTER_SIZE);
1104 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1105 }
1106
1107 #ifdef CTORS_SECTION_ASM_OP
1108 void
1109 ctors_section (void)
1110 {
1111 if (in_section != in_ctors)
1112 {
1113 in_section = in_ctors;
1114 fputs (CTORS_SECTION_ASM_OP, asm_out_file);
1115 fputc ('\n', asm_out_file);
1116 }
1117 }
1118
1119 void
1120 default_ctor_section_asm_out_constructor (rtx symbol,
1121 int priority ATTRIBUTE_UNUSED)
1122 {
1123 ctors_section ();
1124 assemble_align (POINTER_SIZE);
1125 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1126 }
1127 #endif
1128 \f
1129 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1130 a nonzero value if the constant pool should be output before the
1131 start of the function, or a zero value if the pool should output
1132 after the end of the function. The default is to put it before the
1133 start. */
1134
1135 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1136 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1137 #endif
1138
1139 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1140 to be output to assembler.
1141 Set first_global_object_name and weak_global_object_name as appropriate. */
1142
1143 void
1144 notice_global_symbol (tree decl)
1145 {
1146 const char **type = &first_global_object_name;
1147
1148 if (first_global_object_name
1149 || !TREE_PUBLIC (decl) || DECL_EXTERNAL (decl)
1150 || !DECL_NAME (decl)
1151 || (TREE_CODE (decl) != FUNCTION_DECL
1152 && (TREE_CODE (decl) != VAR_DECL
1153 || (DECL_COMMON (decl)
1154 && (DECL_INITIAL (decl) == 0
1155 || DECL_INITIAL (decl) == error_mark_node))))
1156 || !MEM_P (DECL_RTL (decl)))
1157 return;
1158
1159 /* We win when global object is found, but it is useful to know about weak
1160 symbol as well so we can produce nicer unique names. */
1161 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl))
1162 type = &weak_global_object_name;
1163
1164 if (!*type)
1165 {
1166 const char *p;
1167 char *name;
1168 rtx decl_rtl = DECL_RTL (decl);
1169
1170 p = targetm.strip_name_encoding (XSTR (XEXP (decl_rtl, 0), 0));
1171 name = xstrdup (p);
1172
1173 *type = name;
1174 }
1175 }
1176
1177 /* Output assembler code for the constant pool of a function and associated
1178 with defining the name of the function. DECL describes the function.
1179 NAME is the function's name. For the constant pool, we use the current
1180 constant pool data. */
1181
1182 void
1183 assemble_start_function (tree decl, const char *fnname)
1184 {
1185 int align;
1186
1187 if (unlikely_text_section_name)
1188 free (unlikely_text_section_name);
1189
1190 unlikely_section_label_printed = false;
1191 unlikely_text_section_name = NULL;
1192
1193 unlikely_section_label = reconcat (unlikely_section_label,
1194 fnname, ".unlikely_section", NULL);
1195
1196 /* The following code does not need preprocessing in the assembler. */
1197
1198 app_disable ();
1199
1200 if (CONSTANT_POOL_BEFORE_FUNCTION)
1201 output_constant_pool (fnname, decl);
1202
1203 /* Make sure the cold text (code) section is properly aligned. This
1204 is necessary here in the case where the function has both hot and
1205 cold sections, because we don't want to re-set the alignment when the
1206 section switch happens mid-function. We don't need to set the hot
1207 section alignment here, because code further down in this function
1208 sets the alignment for whichever section comes first, and if there
1209 is a hot section it is guaranteed to be first. */
1210
1211 if (flag_reorder_blocks_and_partition)
1212 {
1213 unlikely_text_section ();
1214 assemble_align (FUNCTION_BOUNDARY);
1215 }
1216
1217 resolve_unique_section (decl, 0, flag_function_sections);
1218 function_section (decl);
1219
1220 /* Tell assembler to move to target machine's alignment for functions. */
1221 align = floor_log2 (FUNCTION_BOUNDARY / BITS_PER_UNIT);
1222 if (align < force_align_functions_log)
1223 align = force_align_functions_log;
1224 if (align > 0)
1225 {
1226 ASM_OUTPUT_ALIGN (asm_out_file, align);
1227 }
1228
1229 /* Handle a user-specified function alignment.
1230 Note that we still need to align to FUNCTION_BOUNDARY, as above,
1231 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1232 if (align_functions_log > align
1233 && cfun->function_frequency != FUNCTION_FREQUENCY_UNLIKELY_EXECUTED)
1234 {
1235 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1236 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1237 align_functions_log, align_functions - 1);
1238 #else
1239 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1240 #endif
1241 }
1242
1243 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1244 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1245 #endif
1246
1247 (*debug_hooks->begin_function) (decl);
1248
1249 /* Make function name accessible from other files, if appropriate. */
1250
1251 if (TREE_PUBLIC (decl))
1252 {
1253 notice_global_symbol (decl);
1254
1255 globalize_decl (decl);
1256
1257 maybe_assemble_visibility (decl);
1258 }
1259
1260 if (DECL_PRESERVE_P (decl))
1261 targetm.asm_out.mark_decl_preserved (fnname);
1262
1263 /* Do any machine/system dependent processing of the function name. */
1264 #ifdef ASM_DECLARE_FUNCTION_NAME
1265 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1266 #else
1267 /* Standard thing is just output label for the function. */
1268 ASM_OUTPUT_LABEL (asm_out_file, fnname);
1269 #endif /* ASM_DECLARE_FUNCTION_NAME */
1270
1271 if (in_unlikely_text_section ()
1272 && !unlikely_section_label_printed)
1273 {
1274 ASM_OUTPUT_LABEL (asm_out_file, unlikely_section_label);
1275 unlikely_section_label_printed = true;
1276 }
1277 }
1278
1279 /* Output assembler code associated with defining the size of the
1280 function. DECL describes the function. NAME is the function's name. */
1281
1282 void
1283 assemble_end_function (tree decl, const char *fnname)
1284 {
1285 #ifdef ASM_DECLARE_FUNCTION_SIZE
1286 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1287 #endif
1288 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1289 {
1290 output_constant_pool (fnname, decl);
1291 function_section (decl); /* need to switch back */
1292 }
1293 }
1294 \f
1295 /* Assemble code to leave SIZE bytes of zeros. */
1296
1297 void
1298 assemble_zeros (unsigned HOST_WIDE_INT size)
1299 {
1300 /* Do no output if -fsyntax-only. */
1301 if (flag_syntax_only)
1302 return;
1303
1304 #ifdef ASM_NO_SKIP_IN_TEXT
1305 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1306 so we must output 0s explicitly in the text section. */
1307 if ((ASM_NO_SKIP_IN_TEXT && in_text_section ())
1308 || (ASM_NO_SKIP_IN_TEXT && in_unlikely_text_section ()))
1309 {
1310 unsigned HOST_WIDE_INT i;
1311 for (i = 0; i < size; i++)
1312 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1313 }
1314 else
1315 #endif
1316 if (size > 0)
1317 ASM_OUTPUT_SKIP (asm_out_file, size);
1318 }
1319
1320 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1321
1322 void
1323 assemble_align (int align)
1324 {
1325 if (align > BITS_PER_UNIT)
1326 {
1327 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1328 }
1329 }
1330
1331 /* Assemble a string constant with the specified C string as contents. */
1332
1333 void
1334 assemble_string (const char *p, int size)
1335 {
1336 int pos = 0;
1337 int maximum = 2000;
1338
1339 /* If the string is very long, split it up. */
1340
1341 while (pos < size)
1342 {
1343 int thissize = size - pos;
1344 if (thissize > maximum)
1345 thissize = maximum;
1346
1347 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1348
1349 pos += thissize;
1350 p += thissize;
1351 }
1352 }
1353
1354 \f
1355 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1356 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1357 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1358 #else
1359 #if defined ASM_OUTPUT_ALIGNED_LOCAL
1360 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1361 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, DECL_ALIGN (decl))
1362 #else
1363 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1364 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded)
1365 #endif
1366 #endif
1367
1368 #if defined ASM_OUTPUT_ALIGNED_BSS
1369 #define ASM_EMIT_BSS(decl, name, size, rounded) \
1370 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1371 #else
1372 #if defined ASM_OUTPUT_BSS
1373 #define ASM_EMIT_BSS(decl, name, size, rounded) \
1374 ASM_OUTPUT_BSS (asm_out_file, decl, name, size, rounded)
1375 #else
1376 #undef ASM_EMIT_BSS
1377 #endif
1378 #endif
1379
1380 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1381 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1382 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1383 #else
1384 #if defined ASM_OUTPUT_ALIGNED_COMMON
1385 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1386 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size, DECL_ALIGN (decl))
1387 #else
1388 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1389 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded)
1390 #endif
1391 #endif
1392
1393 static bool
1394 asm_emit_uninitialised (tree decl, const char *name,
1395 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1396 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1397 {
1398 enum
1399 {
1400 asm_dest_common,
1401 asm_dest_bss,
1402 asm_dest_local
1403 }
1404 destination = asm_dest_local;
1405
1406 /* ??? We should handle .bss via select_section mechanisms rather than
1407 via special target hooks. That would eliminate this special case. */
1408 if (TREE_PUBLIC (decl))
1409 {
1410 if (!DECL_COMMON (decl))
1411 #ifdef ASM_EMIT_BSS
1412 destination = asm_dest_bss;
1413 #else
1414 return false;
1415 #endif
1416 else
1417 destination = asm_dest_common;
1418 }
1419
1420 if (destination == asm_dest_bss)
1421 globalize_decl (decl);
1422 resolve_unique_section (decl, 0, flag_data_sections);
1423
1424 if (flag_shared_data)
1425 {
1426 switch (destination)
1427 {
1428 #ifdef ASM_OUTPUT_SHARED_BSS
1429 case asm_dest_bss:
1430 ASM_OUTPUT_SHARED_BSS (asm_out_file, decl, name, size, rounded);
1431 return;
1432 #endif
1433 #ifdef ASM_OUTPUT_SHARED_COMMON
1434 case asm_dest_common:
1435 ASM_OUTPUT_SHARED_COMMON (asm_out_file, name, size, rounded);
1436 return;
1437 #endif
1438 #ifdef ASM_OUTPUT_SHARED_LOCAL
1439 case asm_dest_local:
1440 ASM_OUTPUT_SHARED_LOCAL (asm_out_file, name, size, rounded);
1441 return;
1442 #endif
1443 default:
1444 break;
1445 }
1446 }
1447
1448 switch (destination)
1449 {
1450 #ifdef ASM_EMIT_BSS
1451 case asm_dest_bss:
1452 ASM_EMIT_BSS (decl, name, size, rounded);
1453 break;
1454 #endif
1455 case asm_dest_common:
1456 ASM_EMIT_COMMON (decl, name, size, rounded);
1457 break;
1458 case asm_dest_local:
1459 ASM_EMIT_LOCAL (decl, name, size, rounded);
1460 break;
1461 default:
1462 abort ();
1463 }
1464
1465 return true;
1466 }
1467
1468 /* Assemble everything that is needed for a variable or function declaration.
1469 Not used for automatic variables, and not used for function definitions.
1470 Should not be called for variables of incomplete structure type.
1471
1472 TOP_LEVEL is nonzero if this variable has file scope.
1473 AT_END is nonzero if this is the special handling, at end of compilation,
1474 to define things that have had only tentative definitions.
1475 DONT_OUTPUT_DATA if nonzero means don't actually output the
1476 initial value (that will be done by the caller). */
1477
1478 void
1479 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
1480 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
1481 {
1482 const char *name;
1483 unsigned int align;
1484 int reloc = 0;
1485 rtx decl_rtl;
1486
1487 if (lang_hooks.decls.prepare_assemble_variable)
1488 lang_hooks.decls.prepare_assemble_variable (decl);
1489
1490 last_assemble_variable_decl = 0;
1491
1492 /* Normally no need to say anything here for external references,
1493 since assemble_external is called by the language-specific code
1494 when a declaration is first seen. */
1495
1496 if (DECL_EXTERNAL (decl))
1497 return;
1498
1499 /* Output no assembler code for a function declaration.
1500 Only definitions of functions output anything. */
1501
1502 if (TREE_CODE (decl) == FUNCTION_DECL)
1503 return;
1504
1505 /* Do nothing for global register variables. */
1506 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
1507 {
1508 TREE_ASM_WRITTEN (decl) = 1;
1509 return;
1510 }
1511
1512 /* If type was incomplete when the variable was declared,
1513 see if it is complete now. */
1514
1515 if (DECL_SIZE (decl) == 0)
1516 layout_decl (decl, 0);
1517
1518 /* Still incomplete => don't allocate it; treat the tentative defn
1519 (which is what it must have been) as an `extern' reference. */
1520
1521 if (!dont_output_data && DECL_SIZE (decl) == 0)
1522 {
1523 error ("%Jstorage size of %qD isn%'t known", decl, decl);
1524 TREE_ASM_WRITTEN (decl) = 1;
1525 return;
1526 }
1527
1528 /* The first declaration of a variable that comes through this function
1529 decides whether it is global (in C, has external linkage)
1530 or local (in C, has internal linkage). So do nothing more
1531 if this function has already run. */
1532
1533 if (TREE_ASM_WRITTEN (decl))
1534 return;
1535
1536 /* Make sure targetm.encode_section_info is invoked before we set
1537 ASM_WRITTEN. */
1538 decl_rtl = DECL_RTL (decl);
1539
1540 TREE_ASM_WRITTEN (decl) = 1;
1541
1542 /* Do no output if -fsyntax-only. */
1543 if (flag_syntax_only)
1544 return;
1545
1546 app_disable ();
1547
1548 if (! dont_output_data
1549 && ! host_integerp (DECL_SIZE_UNIT (decl), 1))
1550 {
1551 error ("%Jsize of variable %qD is too large", decl, decl);
1552 return;
1553 }
1554
1555 name = XSTR (XEXP (decl_rtl, 0), 0);
1556 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
1557 notice_global_symbol (decl);
1558
1559 /* Compute the alignment of this data. */
1560
1561 align = DECL_ALIGN (decl);
1562
1563 /* In the case for initialing an array whose length isn't specified,
1564 where we have not yet been able to do the layout,
1565 figure out the proper alignment now. */
1566 if (dont_output_data && DECL_SIZE (decl) == 0
1567 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
1568 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
1569
1570 /* Some object file formats have a maximum alignment which they support.
1571 In particular, a.out format supports a maximum alignment of 4. */
1572 if (align > MAX_OFILE_ALIGNMENT)
1573 {
1574 warning ("%Jalignment of %qD is greater than maximum object "
1575 "file alignment. Using %d", decl, decl,
1576 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
1577 align = MAX_OFILE_ALIGNMENT;
1578 }
1579
1580 /* On some machines, it is good to increase alignment sometimes. */
1581 if (! DECL_USER_ALIGN (decl))
1582 {
1583 #ifdef DATA_ALIGNMENT
1584 align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1585 #endif
1586 #ifdef CONSTANT_ALIGNMENT
1587 if (DECL_INITIAL (decl) != 0 && DECL_INITIAL (decl) != error_mark_node)
1588 align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
1589 #endif
1590 }
1591
1592 /* Reset the alignment in case we have made it tighter, so we can benefit
1593 from it in get_pointer_alignment. */
1594 DECL_ALIGN (decl) = align;
1595 set_mem_align (decl_rtl, align);
1596
1597 if (TREE_PUBLIC (decl))
1598 maybe_assemble_visibility (decl);
1599
1600 if (DECL_PRESERVE_P (decl))
1601 targetm.asm_out.mark_decl_preserved (name);
1602
1603 /* Output any data that we will need to use the address of. */
1604 if (DECL_INITIAL (decl) == error_mark_node)
1605 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1606 else if (DECL_INITIAL (decl))
1607 {
1608 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1609 output_addressed_constants (DECL_INITIAL (decl));
1610 }
1611 resolve_unique_section (decl, reloc, flag_data_sections);
1612
1613 /* Handle uninitialized definitions. */
1614
1615 /* If the decl has been given an explicit section name, then it
1616 isn't common, and shouldn't be handled as such. */
1617 if (DECL_SECTION_NAME (decl) || dont_output_data)
1618 ;
1619 /* We don't implement common thread-local data at present. */
1620 else if (DECL_THREAD_LOCAL (decl))
1621 {
1622 if (DECL_COMMON (decl))
1623 sorry ("thread-local COMMON data not implemented");
1624 }
1625 else if (DECL_INITIAL (decl) == 0
1626 || DECL_INITIAL (decl) == error_mark_node
1627 || (flag_zero_initialized_in_bss
1628 /* Leave constant zeroes in .rodata so they can be shared. */
1629 && !TREE_READONLY (decl)
1630 && initializer_zerop (DECL_INITIAL (decl))))
1631 {
1632 unsigned HOST_WIDE_INT size = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
1633 unsigned HOST_WIDE_INT rounded = size;
1634
1635 /* Don't allocate zero bytes of common,
1636 since that means "undefined external" in the linker. */
1637 if (size == 0)
1638 rounded = 1;
1639
1640 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1641 so that each uninitialized object starts on such a boundary. */
1642 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
1643 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1644 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1645
1646 #if !defined(ASM_OUTPUT_ALIGNED_COMMON) && !defined(ASM_OUTPUT_ALIGNED_DECL_COMMON) && !defined(ASM_OUTPUT_ALIGNED_BSS)
1647 if ((unsigned HOST_WIDE_INT) DECL_ALIGN_UNIT (decl) > rounded)
1648 warning ("%Jrequested alignment for %qD is greater than "
1649 "implemented alignment of %d", decl, decl, rounded);
1650 #endif
1651
1652 /* If the target cannot output uninitialized but not common global data
1653 in .bss, then we have to use .data, so fall through. */
1654 if (asm_emit_uninitialised (decl, name, size, rounded))
1655 return;
1656 }
1657
1658 /* Handle initialized definitions.
1659 Also handle uninitialized global definitions if -fno-common and the
1660 target doesn't support ASM_OUTPUT_BSS. */
1661
1662 /* First make the assembler name(s) global if appropriate. */
1663 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
1664 globalize_decl (decl);
1665
1666 /* Switch to the appropriate section. */
1667 variable_section (decl, reloc);
1668
1669 /* dbxout.c needs to know this. */
1670 if (in_text_section () || in_unlikely_text_section ())
1671 DECL_IN_TEXT_SECTION (decl) = 1;
1672
1673 /* Output the alignment of this data. */
1674 if (align > BITS_PER_UNIT)
1675 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (DECL_ALIGN_UNIT (decl)));
1676
1677 /* Do any machine/system dependent processing of the object. */
1678 #ifdef ASM_DECLARE_OBJECT_NAME
1679 last_assemble_variable_decl = decl;
1680 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
1681 #else
1682 /* Standard thing is just output label for the object. */
1683 ASM_OUTPUT_LABEL (asm_out_file, name);
1684 #endif /* ASM_DECLARE_OBJECT_NAME */
1685
1686 if (!dont_output_data)
1687 {
1688 if (DECL_INITIAL (decl)
1689 && DECL_INITIAL (decl) != error_mark_node
1690 && !initializer_zerop (DECL_INITIAL (decl)))
1691 /* Output the actual data. */
1692 output_constant (DECL_INITIAL (decl),
1693 tree_low_cst (DECL_SIZE_UNIT (decl), 1),
1694 align);
1695 else
1696 /* Leave space for it. */
1697 assemble_zeros (tree_low_cst (DECL_SIZE_UNIT (decl), 1));
1698 }
1699 }
1700
1701 /* Return 1 if type TYPE contains any pointers. */
1702
1703 static int
1704 contains_pointers_p (tree type)
1705 {
1706 switch (TREE_CODE (type))
1707 {
1708 case POINTER_TYPE:
1709 case REFERENCE_TYPE:
1710 /* I'm not sure whether OFFSET_TYPE needs this treatment,
1711 so I'll play safe and return 1. */
1712 case OFFSET_TYPE:
1713 return 1;
1714
1715 case RECORD_TYPE:
1716 case UNION_TYPE:
1717 case QUAL_UNION_TYPE:
1718 {
1719 tree fields;
1720 /* For a type that has fields, see if the fields have pointers. */
1721 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
1722 if (TREE_CODE (fields) == FIELD_DECL
1723 && contains_pointers_p (TREE_TYPE (fields)))
1724 return 1;
1725 return 0;
1726 }
1727
1728 case ARRAY_TYPE:
1729 /* An array type contains pointers if its element type does. */
1730 return contains_pointers_p (TREE_TYPE (type));
1731
1732 default:
1733 return 0;
1734 }
1735 }
1736
1737 #ifdef ASM_OUTPUT_EXTERNAL
1738 /* True if DECL is a function decl for which no out-of-line copy exists.
1739 It is assumed that DECL's assembler name has been set. */
1740
1741 static bool
1742 incorporeal_function_p (tree decl)
1743 {
1744 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
1745 {
1746 const char *name;
1747
1748 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
1749 && DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA)
1750 return true;
1751
1752 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
1753 if (strncmp (name, "__builtin_", strlen ("__builtin_")) == 0)
1754 return true;
1755 }
1756 return false;
1757 }
1758 #endif
1759
1760 /* Output something to declare an external symbol to the assembler.
1761 (Most assemblers don't need this, so we normally output nothing.)
1762 Do nothing if DECL is not external. */
1763
1764 void
1765 assemble_external (tree decl ATTRIBUTE_UNUSED)
1766 {
1767 /* Because most platforms do not define ASM_OUTPUT_EXTERNAL, the
1768 main body of this code is only rarely exercised. To provide some
1769 testing, on all platforms, we make sure that the ASM_OUT_FILE is
1770 open. If it's not, we should not be calling this function. */
1771 if (!asm_out_file)
1772 abort ();
1773
1774 #ifdef ASM_OUTPUT_EXTERNAL
1775 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
1776 {
1777 rtx rtl = DECL_RTL (decl);
1778
1779 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
1780 && !SYMBOL_REF_USED (XEXP (rtl, 0))
1781 && !incorporeal_function_p (decl))
1782 {
1783 /* Some systems do require some output. */
1784 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
1785 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
1786 }
1787 }
1788 #endif
1789 }
1790
1791 /* Similar, for calling a library function FUN. */
1792
1793 void
1794 assemble_external_libcall (rtx fun)
1795 {
1796 /* Declare library function name external when first used, if nec. */
1797 if (! SYMBOL_REF_USED (fun))
1798 {
1799 SYMBOL_REF_USED (fun) = 1;
1800 targetm.asm_out.external_libcall (fun);
1801 }
1802 }
1803
1804 /* Assemble a label named NAME. */
1805
1806 void
1807 assemble_label (const char *name)
1808 {
1809 ASM_OUTPUT_LABEL (asm_out_file, name);
1810 }
1811
1812 /* Set the symbol_referenced flag for ID. */
1813 void
1814 mark_referenced (tree id)
1815 {
1816 TREE_SYMBOL_REFERENCED (id) = 1;
1817 }
1818
1819 /* Set the symbol_referenced flag for DECL and notify callgraph. */
1820 void
1821 mark_decl_referenced (tree decl)
1822 {
1823 if (TREE_CODE (decl) == FUNCTION_DECL)
1824 cgraph_mark_needed_node (cgraph_node (decl));
1825 else if (TREE_CODE (decl) == VAR_DECL)
1826 cgraph_varpool_mark_needed_node (cgraph_varpool_node (decl));
1827 /* else do nothing - we can get various sorts of CST nodes here,
1828 which do not need to be marked. */
1829 }
1830
1831 /* Output to FILE a reference to the assembler name of a C-level name NAME.
1832 If NAME starts with a *, the rest of NAME is output verbatim.
1833 Otherwise NAME is transformed in an implementation-defined way
1834 (usually by the addition of an underscore).
1835 Many macros in the tm file are defined to call this function. */
1836
1837 void
1838 assemble_name (FILE *file, const char *name)
1839 {
1840 const char *real_name;
1841 tree id;
1842
1843 real_name = targetm.strip_name_encoding (name);
1844
1845 id = maybe_get_identifier (real_name);
1846 if (id)
1847 mark_referenced (id);
1848
1849 if (name[0] == '*')
1850 fputs (&name[1], file);
1851 else
1852 ASM_OUTPUT_LABELREF (file, name);
1853 }
1854
1855 /* Allocate SIZE bytes writable static space with a gensym name
1856 and return an RTX to refer to its address. */
1857
1858 rtx
1859 assemble_static_space (unsigned HOST_WIDE_INT size)
1860 {
1861 char name[12];
1862 const char *namestring;
1863 rtx x;
1864
1865 #if 0
1866 if (flag_shared_data)
1867 data_section ();
1868 #endif
1869
1870 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
1871 ++const_labelno;
1872 namestring = ggc_strdup (name);
1873
1874 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
1875 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
1876
1877 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
1878 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
1879 BIGGEST_ALIGNMENT);
1880 #else
1881 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
1882 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
1883 #else
1884 {
1885 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1886 so that each uninitialized object starts on such a boundary. */
1887 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
1888 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
1889 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
1890 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1891 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1892 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1893 }
1894 #endif
1895 #endif
1896 return x;
1897 }
1898
1899 /* Assemble the static constant template for function entry trampolines.
1900 This is done at most once per compilation.
1901 Returns an RTX for the address of the template. */
1902
1903 static GTY(()) rtx initial_trampoline;
1904
1905 #ifdef TRAMPOLINE_TEMPLATE
1906 rtx
1907 assemble_trampoline_template (void)
1908 {
1909 char label[256];
1910 const char *name;
1911 int align;
1912 rtx symbol;
1913
1914 if (initial_trampoline)
1915 return initial_trampoline;
1916
1917 /* By default, put trampoline templates in read-only data section. */
1918
1919 #ifdef TRAMPOLINE_SECTION
1920 TRAMPOLINE_SECTION ();
1921 #else
1922 readonly_data_section ();
1923 #endif
1924
1925 /* Write the assembler code to define one. */
1926 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
1927 if (align > 0)
1928 {
1929 ASM_OUTPUT_ALIGN (asm_out_file, align);
1930 }
1931
1932 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
1933 TRAMPOLINE_TEMPLATE (asm_out_file);
1934
1935 /* Record the rtl to refer to it. */
1936 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
1937 name = ggc_strdup (label);
1938 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
1939 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
1940
1941 initial_trampoline = gen_rtx_MEM (BLKmode, symbol);
1942 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
1943
1944 return initial_trampoline;
1945 }
1946 #endif
1947 \f
1948 /* A and B are either alignments or offsets. Return the minimum alignment
1949 that may be assumed after adding the two together. */
1950
1951 static inline unsigned
1952 min_align (unsigned int a, unsigned int b)
1953 {
1954 return (a | b) & -(a | b);
1955 }
1956
1957 /* Return the assembler directive for creating a given kind of integer
1958 object. SIZE is the number of bytes in the object and ALIGNED_P
1959 indicates whether it is known to be aligned. Return NULL if the
1960 assembly dialect has no such directive.
1961
1962 The returned string should be printed at the start of a new line and
1963 be followed immediately by the object's initial value. */
1964
1965 const char *
1966 integer_asm_op (int size, int aligned_p)
1967 {
1968 struct asm_int_op *ops;
1969
1970 if (aligned_p)
1971 ops = &targetm.asm_out.aligned_op;
1972 else
1973 ops = &targetm.asm_out.unaligned_op;
1974
1975 switch (size)
1976 {
1977 case 1:
1978 return targetm.asm_out.byte_op;
1979 case 2:
1980 return ops->hi;
1981 case 4:
1982 return ops->si;
1983 case 8:
1984 return ops->di;
1985 case 16:
1986 return ops->ti;
1987 default:
1988 return NULL;
1989 }
1990 }
1991
1992 /* Use directive OP to assemble an integer object X. Print OP at the
1993 start of the line, followed immediately by the value of X. */
1994
1995 void
1996 assemble_integer_with_op (const char *op, rtx x)
1997 {
1998 fputs (op, asm_out_file);
1999 output_addr_const (asm_out_file, x);
2000 fputc ('\n', asm_out_file);
2001 }
2002
2003 /* The default implementation of the asm_out.integer target hook. */
2004
2005 bool
2006 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2007 unsigned int size ATTRIBUTE_UNUSED,
2008 int aligned_p ATTRIBUTE_UNUSED)
2009 {
2010 const char *op = integer_asm_op (size, aligned_p);
2011 /* Avoid GAS bugs for values > word size. */
2012 if (size > UNITS_PER_WORD)
2013 return false;
2014 return op && (assemble_integer_with_op (op, x), true);
2015 }
2016
2017 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2018 the alignment of the integer in bits. Return 1 if we were able to output
2019 the constant, otherwise 0. If FORCE is nonzero, abort if we can't output
2020 the constant. */
2021
2022 bool
2023 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2024 {
2025 int aligned_p;
2026
2027 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2028
2029 /* See if the target hook can handle this kind of object. */
2030 if (targetm.asm_out.integer (x, size, aligned_p))
2031 return true;
2032
2033 /* If the object is a multi-byte one, try splitting it up. Split
2034 it into words it if is multi-word, otherwise split it into bytes. */
2035 if (size > 1)
2036 {
2037 enum machine_mode omode, imode;
2038 unsigned int subalign;
2039 unsigned int subsize, i;
2040
2041 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2042 subalign = MIN (align, subsize * BITS_PER_UNIT);
2043 omode = mode_for_size (subsize * BITS_PER_UNIT, MODE_INT, 0);
2044 imode = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
2045
2046 for (i = 0; i < size; i += subsize)
2047 {
2048 rtx partial = simplify_subreg (omode, x, imode, i);
2049 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2050 break;
2051 }
2052 if (i == size)
2053 return true;
2054
2055 /* If we've printed some of it, but not all of it, there's no going
2056 back now. */
2057 if (i > 0)
2058 abort ();
2059 }
2060
2061 if (force)
2062 abort ();
2063
2064 return false;
2065 }
2066 \f
2067 void
2068 assemble_real (REAL_VALUE_TYPE d, enum machine_mode mode, unsigned int align)
2069 {
2070 long data[4];
2071 int i;
2072 int bitsize, nelts, nunits, units_per;
2073
2074 /* This is hairy. We have a quantity of known size. real_to_target
2075 will put it into an array of *host* longs, 32 bits per element
2076 (even if long is more than 32 bits). We need to determine the
2077 number of array elements that are occupied (nelts) and the number
2078 of *target* min-addressable units that will be occupied in the
2079 object file (nunits). We cannot assume that 32 divides the
2080 mode's bitsize (size * BITS_PER_UNIT) evenly.
2081
2082 size * BITS_PER_UNIT is used here to make sure that padding bits
2083 (which might appear at either end of the value; real_to_target
2084 will include the padding bits in its output array) are included. */
2085
2086 nunits = GET_MODE_SIZE (mode);
2087 bitsize = nunits * BITS_PER_UNIT;
2088 nelts = CEIL (bitsize, 32);
2089 units_per = 32 / BITS_PER_UNIT;
2090
2091 real_to_target (data, &d, mode);
2092
2093 /* Put out the first word with the specified alignment. */
2094 assemble_integer (GEN_INT (data[0]), MIN (nunits, units_per), align, 1);
2095 nunits -= units_per;
2096
2097 /* Subsequent words need only 32-bit alignment. */
2098 align = min_align (align, 32);
2099
2100 for (i = 1; i < nelts; i++)
2101 {
2102 assemble_integer (GEN_INT (data[i]), MIN (nunits, units_per), align, 1);
2103 nunits -= units_per;
2104 }
2105 }
2106 \f
2107 /* Given an expression EXP with a constant value,
2108 reduce it to the sum of an assembler symbol and an integer.
2109 Store them both in the structure *VALUE.
2110 Abort if EXP does not reduce. */
2111
2112 struct addr_const GTY(())
2113 {
2114 rtx base;
2115 HOST_WIDE_INT offset;
2116 };
2117
2118 static void
2119 decode_addr_const (tree exp, struct addr_const *value)
2120 {
2121 tree target = TREE_OPERAND (exp, 0);
2122 int offset = 0;
2123 rtx x;
2124
2125 while (1)
2126 {
2127 if (TREE_CODE (target) == COMPONENT_REF
2128 && host_integerp (byte_position (TREE_OPERAND (target, 1)), 0))
2129
2130 {
2131 offset += int_byte_position (TREE_OPERAND (target, 1));
2132 target = TREE_OPERAND (target, 0);
2133 }
2134 else if (TREE_CODE (target) == ARRAY_REF
2135 || TREE_CODE (target) == ARRAY_RANGE_REF)
2136 {
2137 offset += (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (target)), 1)
2138 * tree_low_cst (TREE_OPERAND (target, 1), 0));
2139 target = TREE_OPERAND (target, 0);
2140 }
2141 else
2142 break;
2143 }
2144
2145 switch (TREE_CODE (target))
2146 {
2147 case VAR_DECL:
2148 case FUNCTION_DECL:
2149 x = DECL_RTL (target);
2150 break;
2151
2152 case LABEL_DECL:
2153 x = gen_rtx_MEM (FUNCTION_MODE,
2154 gen_rtx_LABEL_REF (VOIDmode, force_label_rtx (target)));
2155 break;
2156
2157 case REAL_CST:
2158 case STRING_CST:
2159 case COMPLEX_CST:
2160 case CONSTRUCTOR:
2161 case INTEGER_CST:
2162 x = output_constant_def (target, 1);
2163 break;
2164
2165 default:
2166 abort ();
2167 }
2168
2169 if (!MEM_P (x))
2170 abort ();
2171 x = XEXP (x, 0);
2172
2173 value->base = x;
2174 value->offset = offset;
2175 }
2176 \f
2177 /* Uniquize all constants that appear in memory.
2178 Each constant in memory thus far output is recorded
2179 in `const_desc_table'. */
2180
2181 struct constant_descriptor_tree GTY(())
2182 {
2183 /* A MEM for the constant. */
2184 rtx rtl;
2185
2186 /* The value of the constant. */
2187 tree value;
2188 };
2189
2190 static GTY((param_is (struct constant_descriptor_tree)))
2191 htab_t const_desc_htab;
2192
2193 static struct constant_descriptor_tree * build_constant_desc (tree);
2194 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2195
2196 /* Compute a hash code for a constant expression. */
2197
2198 static hashval_t
2199 const_desc_hash (const void *ptr)
2200 {
2201 return const_hash_1 (((struct constant_descriptor_tree *)ptr)->value);
2202 }
2203
2204 static hashval_t
2205 const_hash_1 (const tree exp)
2206 {
2207 const char *p;
2208 hashval_t hi;
2209 int len, i;
2210 enum tree_code code = TREE_CODE (exp);
2211
2212 /* Either set P and LEN to the address and len of something to hash and
2213 exit the switch or return a value. */
2214
2215 switch (code)
2216 {
2217 case INTEGER_CST:
2218 p = (char *) &TREE_INT_CST (exp);
2219 len = sizeof TREE_INT_CST (exp);
2220 break;
2221
2222 case REAL_CST:
2223 return real_hash (TREE_REAL_CST_PTR (exp));
2224
2225 case STRING_CST:
2226 p = TREE_STRING_POINTER (exp);
2227 len = TREE_STRING_LENGTH (exp);
2228 break;
2229
2230 case COMPLEX_CST:
2231 return (const_hash_1 (TREE_REALPART (exp)) * 5
2232 + const_hash_1 (TREE_IMAGPART (exp)));
2233
2234 case CONSTRUCTOR:
2235 if (TREE_CODE (TREE_TYPE (exp)) == SET_TYPE)
2236 {
2237 char *tmp;
2238
2239 len = int_size_in_bytes (TREE_TYPE (exp));
2240 tmp = alloca (len);
2241 get_set_constructor_bytes (exp, (unsigned char *) tmp, len);
2242 p = tmp;
2243 break;
2244 }
2245 else
2246 {
2247 tree link;
2248
2249 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2250
2251 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link))
2252 if (TREE_VALUE (link))
2253 hi = hi * 603 + const_hash_1 (TREE_VALUE (link));
2254
2255 return hi;
2256 }
2257
2258 case ADDR_EXPR:
2259 case FDESC_EXPR:
2260 {
2261 struct addr_const value;
2262
2263 decode_addr_const (exp, &value);
2264 if (GET_CODE (value.base) == SYMBOL_REF)
2265 {
2266 /* Don't hash the address of the SYMBOL_REF;
2267 only use the offset and the symbol name. */
2268 hi = value.offset;
2269 p = XSTR (value.base, 0);
2270 for (i = 0; p[i] != 0; i++)
2271 hi = ((hi * 613) + (unsigned) (p[i]));
2272 }
2273 else if (GET_CODE (value.base) == LABEL_REF)
2274 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13;
2275 else
2276 abort ();
2277 }
2278 return hi;
2279
2280 case PLUS_EXPR:
2281 case MINUS_EXPR:
2282 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2283 + const_hash_1 (TREE_OPERAND (exp, 1)));
2284
2285 case NOP_EXPR:
2286 case CONVERT_EXPR:
2287 case NON_LVALUE_EXPR:
2288 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
2289
2290 default:
2291 /* A language specific constant. Just hash the code. */
2292 return code;
2293 }
2294
2295 /* Compute hashing function. */
2296 hi = len;
2297 for (i = 0; i < len; i++)
2298 hi = ((hi * 613) + (unsigned) (p[i]));
2299
2300 return hi;
2301 }
2302
2303 /* Wrapper of compare_constant, for the htab interface. */
2304 static int
2305 const_desc_eq (const void *p1, const void *p2)
2306 {
2307 return compare_constant (((struct constant_descriptor_tree *)p1)->value,
2308 ((struct constant_descriptor_tree *)p2)->value);
2309 }
2310
2311 /* Compare t1 and t2, and return 1 only if they are known to result in
2312 the same bit pattern on output. */
2313
2314 static int
2315 compare_constant (const tree t1, const tree t2)
2316 {
2317 enum tree_code typecode;
2318
2319 if (t1 == NULL_TREE)
2320 return t2 == NULL_TREE;
2321 if (t2 == NULL_TREE)
2322 return 0;
2323
2324 if (TREE_CODE (t1) != TREE_CODE (t2))
2325 return 0;
2326
2327 switch (TREE_CODE (t1))
2328 {
2329 case INTEGER_CST:
2330 /* Integer constants are the same only if the same width of type. */
2331 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2332 return 0;
2333 return tree_int_cst_equal (t1, t2);
2334
2335 case REAL_CST:
2336 /* Real constants are the same only if the same width of type. */
2337 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2338 return 0;
2339
2340 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
2341
2342 case STRING_CST:
2343 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2344 return 0;
2345
2346 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
2347 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
2348 TREE_STRING_LENGTH (t1)));
2349
2350 case COMPLEX_CST:
2351 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
2352 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
2353
2354 case CONSTRUCTOR:
2355 typecode = TREE_CODE (TREE_TYPE (t1));
2356 if (typecode != TREE_CODE (TREE_TYPE (t2)))
2357 return 0;
2358
2359 if (typecode == SET_TYPE)
2360 {
2361 int len = int_size_in_bytes (TREE_TYPE (t2));
2362 unsigned char *tmp1, *tmp2;
2363
2364 if (int_size_in_bytes (TREE_TYPE (t1)) != len)
2365 return 0;
2366
2367 tmp1 = alloca (len);
2368 tmp2 = alloca (len);
2369
2370 if (get_set_constructor_bytes (t1, tmp1, len) != NULL_TREE)
2371 return 0;
2372 if (get_set_constructor_bytes (t2, tmp2, len) != NULL_TREE)
2373 return 0;
2374
2375 return memcmp (tmp1, tmp2, len) == 0;
2376 }
2377 else
2378 {
2379 tree l1, l2;
2380
2381 if (typecode == ARRAY_TYPE)
2382 {
2383 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
2384 /* For arrays, check that the sizes all match. */
2385 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
2386 || size_1 == -1
2387 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
2388 return 0;
2389 }
2390 else
2391 {
2392 /* For record and union constructors, require exact type
2393 equality. */
2394 if (TREE_TYPE (t1) != TREE_TYPE (t2))
2395 return 0;
2396 }
2397
2398 for (l1 = CONSTRUCTOR_ELTS (t1), l2 = CONSTRUCTOR_ELTS (t2);
2399 l1 && l2;
2400 l1 = TREE_CHAIN (l1), l2 = TREE_CHAIN (l2))
2401 {
2402 /* Check that each value is the same... */
2403 if (! compare_constant (TREE_VALUE (l1), TREE_VALUE (l2)))
2404 return 0;
2405 /* ... and that they apply to the same fields! */
2406 if (typecode == ARRAY_TYPE)
2407 {
2408 if (! compare_constant (TREE_PURPOSE (l1),
2409 TREE_PURPOSE (l2)))
2410 return 0;
2411 }
2412 else
2413 {
2414 if (TREE_PURPOSE (l1) != TREE_PURPOSE (l2))
2415 return 0;
2416 }
2417 }
2418
2419 return l1 == NULL_TREE && l2 == NULL_TREE;
2420 }
2421
2422 case ADDR_EXPR:
2423 case FDESC_EXPR:
2424 {
2425 struct addr_const value1, value2;
2426
2427 decode_addr_const (t1, &value1);
2428 decode_addr_const (t2, &value2);
2429 return (value1.offset == value2.offset
2430 && strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
2431 }
2432
2433 case PLUS_EXPR:
2434 case MINUS_EXPR:
2435 case RANGE_EXPR:
2436 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
2437 && compare_constant(TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
2438
2439 case NOP_EXPR:
2440 case CONVERT_EXPR:
2441 case NON_LVALUE_EXPR:
2442 case VIEW_CONVERT_EXPR:
2443 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
2444
2445 default:
2446 {
2447 tree nt1, nt2;
2448 nt1 = lang_hooks.expand_constant (t1);
2449 nt2 = lang_hooks.expand_constant (t2);
2450 if (nt1 != t1 || nt2 != t2)
2451 return compare_constant (nt1, nt2);
2452 else
2453 return 0;
2454 }
2455 }
2456
2457 /* Should not get here. */
2458 abort ();
2459 }
2460 \f
2461 /* Make a copy of the whole tree structure for a constant. This
2462 handles the same types of nodes that compare_constant handles. */
2463
2464 static tree
2465 copy_constant (tree exp)
2466 {
2467 switch (TREE_CODE (exp))
2468 {
2469 case ADDR_EXPR:
2470 /* For ADDR_EXPR, we do not want to copy the decl whose address
2471 is requested. We do want to copy constants though. */
2472 if (CONSTANT_CLASS_P (TREE_OPERAND (exp, 0)))
2473 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
2474 copy_constant (TREE_OPERAND (exp, 0)));
2475 else
2476 return copy_node (exp);
2477
2478 case INTEGER_CST:
2479 case REAL_CST:
2480 case STRING_CST:
2481 return copy_node (exp);
2482
2483 case COMPLEX_CST:
2484 return build_complex (TREE_TYPE (exp),
2485 copy_constant (TREE_REALPART (exp)),
2486 copy_constant (TREE_IMAGPART (exp)));
2487
2488 case PLUS_EXPR:
2489 case MINUS_EXPR:
2490 return build2 (TREE_CODE (exp), TREE_TYPE (exp),
2491 copy_constant (TREE_OPERAND (exp, 0)),
2492 copy_constant (TREE_OPERAND (exp, 1)));
2493
2494 case NOP_EXPR:
2495 case CONVERT_EXPR:
2496 case NON_LVALUE_EXPR:
2497 case VIEW_CONVERT_EXPR:
2498 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
2499 copy_constant (TREE_OPERAND (exp, 0)));
2500
2501 case CONSTRUCTOR:
2502 {
2503 tree copy = copy_node (exp);
2504 tree list = copy_list (CONSTRUCTOR_ELTS (exp));
2505 tree tail;
2506
2507 CONSTRUCTOR_ELTS (copy) = list;
2508 for (tail = list; tail; tail = TREE_CHAIN (tail))
2509 TREE_VALUE (tail) = copy_constant (TREE_VALUE (tail));
2510 if (TREE_CODE (TREE_TYPE (exp)) == SET_TYPE)
2511 for (tail = list; tail; tail = TREE_CHAIN (tail))
2512 TREE_PURPOSE (tail) = copy_constant (TREE_PURPOSE (tail));
2513
2514 return copy;
2515 }
2516
2517 default:
2518 {
2519 tree t;
2520 t = lang_hooks.expand_constant (exp);
2521 if (t != exp)
2522 return copy_constant (t);
2523 else
2524 abort ();
2525 }
2526 }
2527 }
2528 \f
2529 /* Subroutine of output_constant_def:
2530 No constant equal to EXP is known to have been output.
2531 Make a constant descriptor to enter EXP in the hash table.
2532 Assign the label number and construct RTL to refer to the
2533 constant's location in memory.
2534 Caller is responsible for updating the hash table. */
2535
2536 static struct constant_descriptor_tree *
2537 build_constant_desc (tree exp)
2538 {
2539 rtx symbol;
2540 rtx rtl;
2541 char label[256];
2542 int labelno;
2543 struct constant_descriptor_tree *desc;
2544
2545 desc = ggc_alloc (sizeof (*desc));
2546 desc->value = copy_constant (exp);
2547
2548 /* Propagate marked-ness to copied constant. */
2549 if (flag_mudflap && mf_marked_p (exp))
2550 mf_mark (desc->value);
2551
2552 /* Create a string containing the label name, in LABEL. */
2553 labelno = const_labelno++;
2554 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
2555
2556 /* We have a symbol name; construct the SYMBOL_REF and the MEM. */
2557 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
2558 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2559 SYMBOL_REF_DECL (symbol) = desc->value;
2560 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
2561
2562 rtl = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)), symbol);
2563 set_mem_attributes (rtl, exp, 1);
2564 set_mem_alias_set (rtl, 0);
2565 set_mem_alias_set (rtl, const_alias_set);
2566
2567 /* Set flags or add text to the name to record information, such as
2568 that it is a local symbol. If the name is changed, the macro
2569 ASM_OUTPUT_LABELREF will have to know how to strip this
2570 information. This call might invalidate our local variable
2571 SYMBOL; we can't use it afterward. */
2572
2573 targetm.encode_section_info (exp, rtl, true);
2574
2575 desc->rtl = rtl;
2576
2577 return desc;
2578 }
2579
2580 /* Return an rtx representing a reference to constant data in memory
2581 for the constant expression EXP.
2582
2583 If assembler code for such a constant has already been output,
2584 return an rtx to refer to it.
2585 Otherwise, output such a constant in memory
2586 and generate an rtx for it.
2587
2588 If DEFER is nonzero, this constant can be deferred and output only
2589 if referenced in the function after all optimizations.
2590
2591 `const_desc_table' records which constants already have label strings. */
2592
2593 rtx
2594 output_constant_def (tree exp, int defer)
2595 {
2596 struct constant_descriptor_tree *desc;
2597 struct constant_descriptor_tree key;
2598 void **loc;
2599
2600 /* Look up EXP in the table of constant descriptors. If we didn't find
2601 it, create a new one. */
2602 key.value = exp;
2603 loc = htab_find_slot (const_desc_htab, &key, INSERT);
2604
2605 desc = *loc;
2606 if (desc == 0)
2607 {
2608 desc = build_constant_desc (exp);
2609 *loc = desc;
2610 }
2611
2612 maybe_output_constant_def_contents (desc, defer);
2613 return desc->rtl;
2614 }
2615
2616 /* Subroutine of output_constant_def: Decide whether or not we need to
2617 output the constant DESC now, and if so, do it. */
2618 static void
2619 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
2620 int defer)
2621 {
2622 rtx symbol = XEXP (desc->rtl, 0);
2623 tree exp = desc->value;
2624
2625 if (flag_syntax_only)
2626 return;
2627
2628 if (TREE_ASM_WRITTEN (exp))
2629 /* Already output; don't do it again. */
2630 return;
2631
2632 /* We can always defer constants as long as the context allows
2633 doing so. */
2634 if (defer)
2635 {
2636 /* Increment n_deferred_constants if it exists. It needs to be at
2637 least as large as the number of constants actually referred to
2638 by the function. If it's too small we'll stop looking too early
2639 and fail to emit constants; if it's too large we'll only look
2640 through the entire function when we could have stopped earlier. */
2641 if (cfun)
2642 n_deferred_constants++;
2643 return;
2644 }
2645
2646 output_constant_def_contents (symbol);
2647 }
2648
2649 /* We must output the constant data referred to by SYMBOL; do so. */
2650
2651 static void
2652 output_constant_def_contents (rtx symbol)
2653 {
2654 tree exp = SYMBOL_REF_DECL (symbol);
2655 const char *label = XSTR (symbol, 0);
2656 HOST_WIDE_INT size;
2657
2658 /* Make sure any other constants whose addresses appear in EXP
2659 are assigned label numbers. */
2660 int reloc = compute_reloc_for_constant (exp);
2661
2662 /* Align the location counter as required by EXP's data type. */
2663 unsigned int align = TYPE_ALIGN (TREE_TYPE (exp));
2664 #ifdef CONSTANT_ALIGNMENT
2665 align = CONSTANT_ALIGNMENT (exp, align);
2666 #endif
2667
2668 output_addressed_constants (exp);
2669
2670 /* We are no longer deferring this constant. */
2671 TREE_ASM_WRITTEN (exp) = 1;
2672
2673 if (IN_NAMED_SECTION (exp))
2674 named_section (exp, NULL, reloc);
2675 else
2676 targetm.asm_out.select_section (exp, reloc, align);
2677
2678 if (align > BITS_PER_UNIT)
2679 {
2680 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2681 }
2682
2683 size = int_size_in_bytes (TREE_TYPE (exp));
2684 if (TREE_CODE (exp) == STRING_CST)
2685 size = MAX (TREE_STRING_LENGTH (exp), size);
2686
2687 /* Do any machine/system dependent processing of the constant. */
2688 #ifdef ASM_DECLARE_CONSTANT_NAME
2689 ASM_DECLARE_CONSTANT_NAME (asm_out_file, label, exp, size);
2690 #else
2691 /* Standard thing is just output label for the constant. */
2692 ASM_OUTPUT_LABEL (asm_out_file, label);
2693 #endif /* ASM_DECLARE_CONSTANT_NAME */
2694
2695 /* Output the value of EXP. */
2696 output_constant (exp, size, align);
2697 if (flag_mudflap)
2698 mudflap_enqueue_constant (exp);
2699 }
2700
2701 /* Look up EXP in the table of constant descriptors. Return the rtl
2702 if it has been emitted, else null. */
2703
2704 rtx
2705 lookup_constant_def (tree exp)
2706 {
2707 struct constant_descriptor_tree *desc;
2708 struct constant_descriptor_tree key;
2709
2710 key.value = exp;
2711 desc = htab_find (const_desc_htab, &key);
2712
2713 return (desc ? desc->rtl : NULL_RTX);
2714 }
2715 \f
2716 /* Used in the hash tables to avoid outputting the same constant
2717 twice. Unlike 'struct constant_descriptor_tree', RTX constants
2718 are output once per function, not once per file. */
2719 /* ??? Only a few targets need per-function constant pools. Most
2720 can use one per-file pool. Should add a targetm bit to tell the
2721 difference. */
2722
2723 struct rtx_constant_pool GTY(())
2724 {
2725 /* Pointers to first and last constant in pool, as ordered by offset. */
2726 struct constant_descriptor_rtx *first;
2727 struct constant_descriptor_rtx *last;
2728
2729 /* Hash facility for making memory-constants from constant rtl-expressions.
2730 It is used on RISC machines where immediate integer arguments and
2731 constant addresses are restricted so that such constants must be stored
2732 in memory. */
2733 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_htab;
2734 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_sym_htab;
2735
2736 /* Current offset in constant pool (does not include any
2737 machine-specific header). */
2738 HOST_WIDE_INT offset;
2739 };
2740
2741 struct constant_descriptor_rtx GTY((chain_next ("%h.next")))
2742 {
2743 struct constant_descriptor_rtx *next;
2744 rtx mem;
2745 rtx sym;
2746 rtx constant;
2747 HOST_WIDE_INT offset;
2748 hashval_t hash;
2749 enum machine_mode mode;
2750 unsigned int align;
2751 int labelno;
2752 int mark;
2753 };
2754
2755 /* Hash and compare functions for const_rtx_htab. */
2756
2757 static hashval_t
2758 const_desc_rtx_hash (const void *ptr)
2759 {
2760 const struct constant_descriptor_rtx *desc = ptr;
2761 return desc->hash;
2762 }
2763
2764 static int
2765 const_desc_rtx_eq (const void *a, const void *b)
2766 {
2767 const struct constant_descriptor_rtx *x = a;
2768 const struct constant_descriptor_rtx *y = b;
2769
2770 if (x->mode != y->mode)
2771 return 0;
2772 return rtx_equal_p (x->constant, y->constant);
2773 }
2774
2775 /* Hash and compare functions for const_rtx_sym_htab. */
2776
2777 static hashval_t
2778 const_desc_rtx_sym_hash (const void *ptr)
2779 {
2780 const struct constant_descriptor_rtx *desc = ptr;
2781 return htab_hash_string (XSTR (desc->sym, 0));
2782 }
2783
2784 static int
2785 const_desc_rtx_sym_eq (const void *a, const void *b)
2786 {
2787 const struct constant_descriptor_rtx *x = a;
2788 const struct constant_descriptor_rtx *y = b;
2789 return XSTR (x->sym, 0) == XSTR (y->sym, 0);
2790 }
2791
2792 /* This is the worker function for const_rtx_hash, called via for_each_rtx. */
2793
2794 static int
2795 const_rtx_hash_1 (rtx *xp, void *data)
2796 {
2797 unsigned HOST_WIDE_INT hwi;
2798 enum machine_mode mode;
2799 enum rtx_code code;
2800 hashval_t h, *hp;
2801 rtx x;
2802
2803 x = *xp;
2804 code = GET_CODE (x);
2805 mode = GET_MODE (x);
2806 h = (hashval_t) code * 1048573 + mode;
2807
2808 switch (code)
2809 {
2810 case CONST_INT:
2811 hwi = INTVAL (x);
2812 fold_hwi:
2813 {
2814 const int shift = sizeof (hashval_t) * CHAR_BIT;
2815 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
2816 int i;
2817
2818 h ^= (hashval_t) hwi;
2819 for (i = 1; i < n; ++i)
2820 {
2821 hwi >>= shift;
2822 h ^= (hashval_t) hwi;
2823 }
2824 }
2825 break;
2826
2827 case CONST_DOUBLE:
2828 if (mode == VOIDmode)
2829 {
2830 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
2831 goto fold_hwi;
2832 }
2833 else
2834 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
2835 break;
2836
2837 case SYMBOL_REF:
2838 h ^= htab_hash_string (XSTR (x, 0));
2839 break;
2840
2841 case LABEL_REF:
2842 h = h * 251 + CODE_LABEL_NUMBER (XEXP (x, 0));
2843 break;
2844
2845 case UNSPEC:
2846 case UNSPEC_VOLATILE:
2847 h = h * 251 + XINT (x, 1);
2848 break;
2849
2850 default:
2851 break;
2852 }
2853
2854 hp = data;
2855 *hp = *hp * 509 + h;
2856 return 0;
2857 }
2858
2859 /* Compute a hash value for X, which should be a constant. */
2860
2861 static hashval_t
2862 const_rtx_hash (rtx x)
2863 {
2864 hashval_t h = 0;
2865 for_each_rtx (&x, const_rtx_hash_1, &h);
2866 return h;
2867 }
2868
2869 \f
2870 /* Initialize constant pool hashing for a new function. */
2871
2872 void
2873 init_varasm_status (struct function *f)
2874 {
2875 struct varasm_status *p;
2876 struct rtx_constant_pool *pool;
2877
2878 p = ggc_alloc (sizeof (struct varasm_status));
2879 f->varasm = p;
2880
2881 pool = ggc_alloc (sizeof (struct rtx_constant_pool));
2882 p->pool = pool;
2883 p->deferred_constants = 0;
2884
2885 pool->const_rtx_htab = htab_create_ggc (31, const_desc_rtx_hash,
2886 const_desc_rtx_eq, NULL);
2887 pool->const_rtx_sym_htab = htab_create_ggc (31, const_desc_rtx_sym_hash,
2888 const_desc_rtx_sym_eq, NULL);
2889 pool->first = pool->last = NULL;
2890 pool->offset = 0;
2891 }
2892 \f
2893 /* Given a MINUS expression, simplify it if both sides
2894 include the same symbol. */
2895
2896 rtx
2897 simplify_subtraction (rtx x)
2898 {
2899 rtx r = simplify_rtx (x);
2900 return r ? r : x;
2901 }
2902 \f
2903 /* Given a constant rtx X, make (or find) a memory constant for its value
2904 and return a MEM rtx to refer to it in memory. */
2905
2906 rtx
2907 force_const_mem (enum machine_mode mode, rtx x)
2908 {
2909 struct constant_descriptor_rtx *desc, tmp;
2910 struct rtx_constant_pool *pool = cfun->varasm->pool;
2911 char label[256];
2912 rtx def, symbol;
2913 hashval_t hash;
2914 unsigned int align;
2915 void **slot;
2916
2917 /* If we're not allowed to drop X into the constant pool, don't. */
2918 if (targetm.cannot_force_const_mem (x))
2919 return NULL_RTX;
2920
2921 /* Lookup the value in the hashtable. */
2922 tmp.constant = x;
2923 tmp.mode = mode;
2924 hash = const_rtx_hash (x);
2925 slot = htab_find_slot_with_hash (pool->const_rtx_htab, &tmp, hash, INSERT);
2926 desc = *slot;
2927
2928 /* If the constant was already present, return its memory. */
2929 if (desc)
2930 return copy_rtx (desc->mem);
2931
2932 /* Otherwise, create a new descriptor. */
2933 desc = ggc_alloc (sizeof (*desc));
2934 *slot = desc;
2935
2936 /* Align the location counter as required by EXP's data type. */
2937 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
2938 #ifdef CONSTANT_ALIGNMENT
2939 {
2940 tree type = lang_hooks.types.type_for_mode (mode, 0);
2941 if (type != NULL_TREE)
2942 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
2943 }
2944 #endif
2945
2946 pool->offset += (align / BITS_PER_UNIT) - 1;
2947 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
2948
2949 desc->next = NULL;
2950 desc->constant = tmp.constant;
2951 desc->offset = pool->offset;
2952 desc->hash = hash;
2953 desc->mode = mode;
2954 desc->align = align;
2955 desc->labelno = const_labelno;
2956 desc->mark = 0;
2957
2958 pool->offset += GET_MODE_SIZE (mode);
2959 if (pool->last)
2960 pool->last->next = desc;
2961 else
2962 pool->first = pool->last = desc;
2963 pool->last = desc;
2964
2965 /* Create a string containing the label name, in LABEL. */
2966 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
2967 ++const_labelno;
2968
2969 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
2970 the constants pool. */
2971 desc->sym = symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
2972 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2973 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
2974 current_function_uses_const_pool = 1;
2975
2976 /* Insert the descriptor into the symbol cross-reference table too. */
2977 slot = htab_find_slot (pool->const_rtx_sym_htab, desc, INSERT);
2978 if (*slot)
2979 abort ();
2980 *slot = desc;
2981
2982 /* Construct the MEM. */
2983 desc->mem = def = gen_const_mem (mode, symbol);
2984 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
2985
2986 /* If we're dropping a label to the constant pool, make sure we
2987 don't delete it. */
2988 if (GET_CODE (x) == LABEL_REF)
2989 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
2990
2991 return copy_rtx (def);
2992 }
2993 \f
2994 /* Given a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true, return a pointer to
2995 the corresponding constant_descriptor_rtx structure. */
2996
2997 static struct constant_descriptor_rtx *
2998 find_pool_constant (struct rtx_constant_pool *pool, rtx sym)
2999 {
3000 struct constant_descriptor_rtx tmp;
3001 tmp.sym = sym;
3002 return htab_find (pool->const_rtx_sym_htab, &tmp);
3003 }
3004
3005 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3006
3007 rtx
3008 get_pool_constant (rtx addr)
3009 {
3010 return find_pool_constant (cfun->varasm->pool, addr)->constant;
3011 }
3012
3013 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3014 and whether it has been output or not. */
3015
3016 rtx
3017 get_pool_constant_mark (rtx addr, bool *pmarked)
3018 {
3019 struct constant_descriptor_rtx *desc;
3020
3021 desc = find_pool_constant (cfun->varasm->pool, addr);
3022 *pmarked = (desc->mark != 0);
3023 return desc->constant;
3024 }
3025
3026 /* Likewise, but for the constant pool of a specific function. */
3027
3028 rtx
3029 get_pool_constant_for_function (struct function *f, rtx addr)
3030 {
3031 return find_pool_constant (f->varasm->pool, addr)->constant;
3032 }
3033
3034 /* Similar, return the mode. */
3035
3036 enum machine_mode
3037 get_pool_mode (rtx addr)
3038 {
3039 return find_pool_constant (cfun->varasm->pool, addr)->mode;
3040 }
3041
3042 enum machine_mode
3043 get_pool_mode_for_function (struct function *f, rtx addr)
3044 {
3045 return find_pool_constant (f->varasm->pool, addr)->mode;
3046 }
3047
3048 /* Similar, return the offset in the constant pool. */
3049
3050 int
3051 get_pool_offset (rtx addr)
3052 {
3053 return find_pool_constant (cfun->varasm->pool, addr)->offset;
3054 }
3055
3056 /* Return the size of the constant pool. */
3057
3058 int
3059 get_pool_size (void)
3060 {
3061 return cfun->varasm->pool->offset;
3062 }
3063 \f
3064 /* Worker function for output_constant_pool_1. Emit assembly for X
3065 in MODE with known alignment ALIGN. */
3066
3067 static void
3068 output_constant_pool_2 (enum machine_mode mode, rtx x, unsigned int align)
3069 {
3070 switch (GET_MODE_CLASS (mode))
3071 {
3072 case MODE_FLOAT:
3073 if (GET_CODE (x) != CONST_DOUBLE)
3074 abort ();
3075 else
3076 {
3077 REAL_VALUE_TYPE r;
3078 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3079 assemble_real (r, mode, align);
3080 }
3081 break;
3082
3083 case MODE_INT:
3084 case MODE_PARTIAL_INT:
3085 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3086 break;
3087
3088 case MODE_VECTOR_FLOAT:
3089 case MODE_VECTOR_INT:
3090 {
3091 int i, units;
3092 enum machine_mode submode = GET_MODE_INNER (mode);
3093 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3094
3095 if (GET_CODE (x) != CONST_VECTOR)
3096 abort ();
3097 units = CONST_VECTOR_NUNITS (x);
3098
3099 for (i = 0; i < units; i++)
3100 {
3101 rtx elt = CONST_VECTOR_ELT (x, i);
3102 output_constant_pool_2 (submode, elt, i ? subalign : align);
3103 }
3104 }
3105 break;
3106
3107 default:
3108 abort ();
3109 }
3110 }
3111
3112 /* Worker function for output_constant_pool. Emit POOL. */
3113
3114 static void
3115 output_constant_pool_1 (struct constant_descriptor_rtx *desc)
3116 {
3117 rtx x, tmp;
3118
3119 if (!desc->mark)
3120 return;
3121 x = desc->constant;
3122
3123 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3124 whose CODE_LABEL has been deleted. This can occur if a jump table
3125 is eliminated by optimization. If so, write a constant of zero
3126 instead. Note that this can also happen by turning the
3127 CODE_LABEL into a NOTE. */
3128 /* ??? This seems completely and utterly wrong. Certainly it's
3129 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3130 functioning even with INSN_DELETED_P and friends. */
3131
3132 tmp = x;
3133 switch (GET_CODE (x))
3134 {
3135 case CONST:
3136 if (GET_CODE (XEXP (x, 0)) != PLUS
3137 || GET_CODE (XEXP (XEXP (x, 0), 0)) != LABEL_REF)
3138 break;
3139 tmp = XEXP (XEXP (x, 0), 0);
3140 /* FALLTHRU */
3141
3142 case LABEL_REF:
3143 tmp = XEXP (x, 0);
3144 if (INSN_DELETED_P (tmp)
3145 || (NOTE_P (tmp)
3146 && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_DELETED))
3147 {
3148 abort ();
3149 x = const0_rtx;
3150 }
3151 break;
3152
3153 default:
3154 break;
3155 }
3156
3157 /* First switch to correct section. */
3158 targetm.asm_out.select_rtx_section (desc->mode, x, desc->align);
3159
3160 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3161 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3162 desc->align, desc->labelno, done);
3163 #endif
3164
3165 assemble_align (desc->align);
3166
3167 /* Output the label. */
3168 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3169
3170 /* Output the data. */
3171 output_constant_pool_2 (desc->mode, x, desc->align);
3172
3173 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3174 sections have proper size. */
3175 if (desc->align > GET_MODE_BITSIZE (desc->mode)
3176 && in_section == in_named
3177 && get_named_section_flags (in_named_name) & SECTION_MERGE)
3178 assemble_align (desc->align);
3179
3180 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3181 done:
3182 #endif
3183 return;
3184 }
3185
3186 /* Given a SYMBOL_REF CURRENT_RTX, mark it and all constants it refers
3187 to as used. Emit referenced deferred strings. This function can
3188 be used with for_each_rtx to mark all SYMBOL_REFs in an rtx. */
3189
3190 static int
3191 mark_constant (rtx *current_rtx, void *data)
3192 {
3193 struct rtx_constant_pool *pool = data;
3194 rtx x = *current_rtx;
3195
3196 if (x == NULL_RTX || GET_CODE (x) != SYMBOL_REF)
3197 return 0;
3198
3199 if (CONSTANT_POOL_ADDRESS_P (x))
3200 {
3201 struct constant_descriptor_rtx *desc = find_pool_constant (pool, x);
3202 if (desc->mark == 0)
3203 {
3204 desc->mark = 1;
3205 for_each_rtx (&desc->constant, mark_constant, pool);
3206 }
3207 }
3208 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3209 {
3210 tree exp = SYMBOL_REF_DECL (x);
3211 if (!TREE_ASM_WRITTEN (exp))
3212 {
3213 n_deferred_constants--;
3214 output_constant_def_contents (x);
3215 }
3216 }
3217
3218 return -1;
3219 }
3220
3221 /* Look through appropriate parts of INSN, marking all entries in the
3222 constant pool which are actually being used. Entries that are only
3223 referenced by other constants are also marked as used. Emit
3224 deferred strings that are used. */
3225
3226 static void
3227 mark_constants (struct rtx_constant_pool *pool, rtx insn)
3228 {
3229 if (!INSN_P (insn))
3230 return;
3231
3232 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3233 insns, not any notes that may be attached. We don't want to mark
3234 a constant just because it happens to appear in a REG_EQUIV note. */
3235 if (GET_CODE (PATTERN (insn)) == SEQUENCE)
3236 {
3237 rtx seq = PATTERN (insn);
3238 int i, n = XVECLEN (seq, 0);
3239 for (i = 0; i < n; ++i)
3240 {
3241 rtx subinsn = XVECEXP (seq, 0, i);
3242 if (INSN_P (subinsn))
3243 for_each_rtx (&PATTERN (subinsn), mark_constant, pool);
3244 }
3245 }
3246 else
3247 for_each_rtx (&PATTERN (insn), mark_constant, pool);
3248 }
3249
3250 /* Look through the instructions for this function, and mark all the
3251 entries in POOL which are actually being used. Emit deferred constants
3252 which have indeed been used. */
3253
3254 static void
3255 mark_constant_pool (struct rtx_constant_pool *pool)
3256 {
3257 rtx insn, link;
3258
3259 if (pool->first == 0 && n_deferred_constants == 0)
3260 return;
3261
3262 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3263 mark_constants (pool, insn);
3264
3265 for (link = current_function_epilogue_delay_list;
3266 link;
3267 link = XEXP (link, 1))
3268 mark_constants (pool, XEXP (link, 0));
3269 }
3270
3271 /* Write all the constants in the constant pool. */
3272
3273 void
3274 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
3275 tree fndecl ATTRIBUTE_UNUSED)
3276 {
3277 struct rtx_constant_pool *pool = cfun->varasm->pool;
3278 struct constant_descriptor_rtx *desc;
3279
3280 /* It is possible for gcc to call force_const_mem and then to later
3281 discard the instructions which refer to the constant. In such a
3282 case we do not need to output the constant. */
3283 mark_constant_pool (pool);
3284
3285 #ifdef ASM_OUTPUT_POOL_PROLOGUE
3286 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
3287 #endif
3288
3289 for (desc = pool->first; desc ; desc = desc->next)
3290 output_constant_pool_1 (desc);
3291
3292 #ifdef ASM_OUTPUT_POOL_EPILOGUE
3293 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
3294 #endif
3295 }
3296 \f
3297 /* Determine what kind of relocations EXP may need. */
3298
3299 int
3300 compute_reloc_for_constant (tree exp)
3301 {
3302 int reloc = 0, reloc2;
3303 tree tem;
3304
3305 /* Give the front-end a chance to convert VALUE to something that
3306 looks more like a constant to the back-end. */
3307 exp = lang_hooks.expand_constant (exp);
3308
3309 switch (TREE_CODE (exp))
3310 {
3311 case ADDR_EXPR:
3312 case FDESC_EXPR:
3313 /* Go inside any operations that get_inner_reference can handle and see
3314 if what's inside is a constant: no need to do anything here for
3315 addresses of variables or functions. */
3316 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
3317 tem = TREE_OPERAND (tem, 0))
3318 ;
3319
3320 if (TREE_PUBLIC (tem))
3321 reloc |= 2;
3322 else
3323 reloc |= 1;
3324 break;
3325
3326 case PLUS_EXPR:
3327 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3328 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
3329 break;
3330
3331 case MINUS_EXPR:
3332 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3333 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
3334 /* The difference of two local labels is computable at link time. */
3335 if (reloc == 1 && reloc2 == 1)
3336 reloc = 0;
3337 else
3338 reloc |= reloc2;
3339 break;
3340
3341 case NOP_EXPR:
3342 case CONVERT_EXPR:
3343 case NON_LVALUE_EXPR:
3344 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3345 break;
3346
3347 case CONSTRUCTOR:
3348 for (tem = CONSTRUCTOR_ELTS (exp); tem; tem = TREE_CHAIN (tem))
3349 if (TREE_VALUE (tem) != 0)
3350 reloc |= compute_reloc_for_constant (TREE_VALUE (tem));
3351
3352 break;
3353
3354 default:
3355 break;
3356 }
3357 return reloc;
3358 }
3359
3360 /* Find all the constants whose addresses are referenced inside of EXP,
3361 and make sure assembler code with a label has been output for each one.
3362 Indicate whether an ADDR_EXPR has been encountered. */
3363
3364 static void
3365 output_addressed_constants (tree exp)
3366 {
3367 tree tem;
3368
3369 /* Give the front-end a chance to convert VALUE to something that
3370 looks more like a constant to the back-end. */
3371 exp = lang_hooks.expand_constant (exp);
3372
3373 switch (TREE_CODE (exp))
3374 {
3375 case ADDR_EXPR:
3376 case FDESC_EXPR:
3377 /* Go inside any operations that get_inner_reference can handle and see
3378 if what's inside is a constant: no need to do anything here for
3379 addresses of variables or functions. */
3380 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
3381 tem = TREE_OPERAND (tem, 0))
3382 ;
3383
3384 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
3385 output_constant_def (tem, 0);
3386 break;
3387
3388 case PLUS_EXPR:
3389 case MINUS_EXPR:
3390 output_addressed_constants (TREE_OPERAND (exp, 1));
3391 /* Fall through. */
3392
3393 case NOP_EXPR:
3394 case CONVERT_EXPR:
3395 case NON_LVALUE_EXPR:
3396 output_addressed_constants (TREE_OPERAND (exp, 0));
3397 break;
3398
3399 case CONSTRUCTOR:
3400 for (tem = CONSTRUCTOR_ELTS (exp); tem; tem = TREE_CHAIN (tem))
3401 if (TREE_VALUE (tem) != 0)
3402 output_addressed_constants (TREE_VALUE (tem));
3403
3404 break;
3405
3406 default:
3407 break;
3408 }
3409 }
3410 \f
3411 /* Return nonzero if VALUE is a valid constant-valued expression
3412 for use in initializing a static variable; one that can be an
3413 element of a "constant" initializer.
3414
3415 Return null_pointer_node if the value is absolute;
3416 if it is relocatable, return the variable that determines the relocation.
3417 We assume that VALUE has been folded as much as possible;
3418 therefore, we do not need to check for such things as
3419 arithmetic-combinations of integers. */
3420
3421 tree
3422 initializer_constant_valid_p (tree value, tree endtype)
3423 {
3424 /* Give the front-end a chance to convert VALUE to something that
3425 looks more like a constant to the back-end. */
3426 value = lang_hooks.expand_constant (value);
3427
3428 switch (TREE_CODE (value))
3429 {
3430 case CONSTRUCTOR:
3431 if ((TREE_CODE (TREE_TYPE (value)) == UNION_TYPE
3432 || TREE_CODE (TREE_TYPE (value)) == RECORD_TYPE)
3433 && TREE_CONSTANT (value)
3434 && CONSTRUCTOR_ELTS (value))
3435 {
3436 tree elt;
3437 bool absolute = true;
3438
3439 for (elt = CONSTRUCTOR_ELTS (value); elt; elt = TREE_CHAIN (elt))
3440 {
3441 tree reloc;
3442 value = TREE_VALUE (elt);
3443 reloc = initializer_constant_valid_p (value, TREE_TYPE (value));
3444 if (!reloc)
3445 return NULL_TREE;
3446 if (reloc != null_pointer_node)
3447 absolute = false;
3448 }
3449 /* For a non-absolute relocation, there is no single
3450 variable that can be "the variable that determines the
3451 relocation." */
3452 return absolute ? null_pointer_node : error_mark_node;
3453 }
3454
3455 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
3456
3457 case INTEGER_CST:
3458 case VECTOR_CST:
3459 case REAL_CST:
3460 case STRING_CST:
3461 case COMPLEX_CST:
3462 return null_pointer_node;
3463
3464 case ADDR_EXPR:
3465 case FDESC_EXPR:
3466 value = staticp (TREE_OPERAND (value, 0));
3467 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out to
3468 be a constant, this is old-skool offsetof-like nonsense. */
3469 if (value
3470 && TREE_CODE (value) == INDIRECT_REF
3471 && TREE_CONSTANT (TREE_OPERAND (value, 0)))
3472 return null_pointer_node;
3473 return value;
3474
3475 case VIEW_CONVERT_EXPR:
3476 case NON_LVALUE_EXPR:
3477 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3478
3479 case CONVERT_EXPR:
3480 case NOP_EXPR:
3481 /* Allow conversions between pointer types. */
3482 if (POINTER_TYPE_P (TREE_TYPE (value))
3483 && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3484 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3485
3486 /* Allow conversions between real types. */
3487 if (FLOAT_TYPE_P (TREE_TYPE (value))
3488 && FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3489 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3490
3491 /* Allow length-preserving conversions between integer types. */
3492 if (INTEGRAL_TYPE_P (TREE_TYPE (value))
3493 && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0)))
3494 && (TYPE_PRECISION (TREE_TYPE (value))
3495 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0)))))
3496 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3497
3498 /* Allow conversions between other integer types only if
3499 explicit value. */
3500 if (INTEGRAL_TYPE_P (TREE_TYPE (value))
3501 && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3502 {
3503 tree inner = initializer_constant_valid_p (TREE_OPERAND (value, 0),
3504 endtype);
3505 if (inner == null_pointer_node)
3506 return null_pointer_node;
3507 break;
3508 }
3509
3510 /* Allow (int) &foo provided int is as wide as a pointer. */
3511 if (INTEGRAL_TYPE_P (TREE_TYPE (value))
3512 && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0)))
3513 && (TYPE_PRECISION (TREE_TYPE (value))
3514 >= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0)))))
3515 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
3516 endtype);
3517
3518 /* Likewise conversions from int to pointers, but also allow
3519 conversions from 0. */
3520 if ((POINTER_TYPE_P (TREE_TYPE (value))
3521 || TREE_CODE (TREE_TYPE (value)) == OFFSET_TYPE)
3522 && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3523 {
3524 if (integer_zerop (TREE_OPERAND (value, 0)))
3525 return null_pointer_node;
3526 else if (TYPE_PRECISION (TREE_TYPE (value))
3527 <= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0))))
3528 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
3529 endtype);
3530 }
3531
3532 /* Allow conversions to struct or union types if the value
3533 inside is okay. */
3534 if (TREE_CODE (TREE_TYPE (value)) == RECORD_TYPE
3535 || TREE_CODE (TREE_TYPE (value)) == UNION_TYPE)
3536 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
3537 endtype);
3538 break;
3539
3540 case PLUS_EXPR:
3541 if (! INTEGRAL_TYPE_P (endtype)
3542 || TYPE_PRECISION (endtype) >= POINTER_SIZE)
3543 {
3544 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0),
3545 endtype);
3546 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1),
3547 endtype);
3548 /* If either term is absolute, use the other terms relocation. */
3549 if (valid0 == null_pointer_node)
3550 return valid1;
3551 if (valid1 == null_pointer_node)
3552 return valid0;
3553 }
3554 break;
3555
3556 case MINUS_EXPR:
3557 if (! INTEGRAL_TYPE_P (endtype)
3558 || TYPE_PRECISION (endtype) >= POINTER_SIZE)
3559 {
3560 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0),
3561 endtype);
3562 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1),
3563 endtype);
3564 /* Win if second argument is absolute. */
3565 if (valid1 == null_pointer_node)
3566 return valid0;
3567 /* Win if both arguments have the same relocation.
3568 Then the value is absolute. */
3569 if (valid0 == valid1 && valid0 != 0)
3570 return null_pointer_node;
3571
3572 /* Since GCC guarantees that string constants are unique in the
3573 generated code, a subtraction between two copies of the same
3574 constant string is absolute. */
3575 if (valid0 && TREE_CODE (valid0) == STRING_CST
3576 && valid1 && TREE_CODE (valid1) == STRING_CST
3577 && operand_equal_p (valid0, valid1, 1))
3578 return null_pointer_node;
3579 }
3580
3581 /* Support narrowing differences. */
3582 if (INTEGRAL_TYPE_P (endtype))
3583 {
3584 tree op0, op1;
3585
3586 op0 = TREE_OPERAND (value, 0);
3587 op1 = TREE_OPERAND (value, 1);
3588
3589 /* Like STRIP_NOPS except allow the operand mode to widen.
3590 This works around a feature of fold that simplifies
3591 (int)(p1 - p2) to ((int)p1 - (int)p2) under the theory
3592 that the narrower operation is cheaper. */
3593
3594 while (TREE_CODE (op0) == NOP_EXPR
3595 || TREE_CODE (op0) == CONVERT_EXPR
3596 || TREE_CODE (op0) == NON_LVALUE_EXPR)
3597 {
3598 tree inner = TREE_OPERAND (op0, 0);
3599 if (inner == error_mark_node
3600 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
3601 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
3602 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
3603 break;
3604 op0 = inner;
3605 }
3606
3607 while (TREE_CODE (op1) == NOP_EXPR
3608 || TREE_CODE (op1) == CONVERT_EXPR
3609 || TREE_CODE (op1) == NON_LVALUE_EXPR)
3610 {
3611 tree inner = TREE_OPERAND (op1, 0);
3612 if (inner == error_mark_node
3613 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
3614 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
3615 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
3616 break;
3617 op1 = inner;
3618 }
3619
3620 op0 = initializer_constant_valid_p (op0, endtype);
3621 op1 = initializer_constant_valid_p (op1, endtype);
3622
3623 /* Both initializers must be known. */
3624 if (op0 && op1)
3625 {
3626 if (op0 == op1)
3627 return null_pointer_node;
3628
3629 /* Support differences between labels. */
3630 if (TREE_CODE (op0) == LABEL_DECL
3631 && TREE_CODE (op1) == LABEL_DECL)
3632 return null_pointer_node;
3633
3634 if (TREE_CODE (op0) == STRING_CST
3635 && TREE_CODE (op1) == STRING_CST
3636 && operand_equal_p (op0, op1, 1))
3637 return null_pointer_node;
3638 }
3639 }
3640 break;
3641
3642 default:
3643 break;
3644 }
3645
3646 return 0;
3647 }
3648 \f
3649 /* Output assembler code for constant EXP to FILE, with no label.
3650 This includes the pseudo-op such as ".int" or ".byte", and a newline.
3651 Assumes output_addressed_constants has been done on EXP already.
3652
3653 Generate exactly SIZE bytes of assembler data, padding at the end
3654 with zeros if necessary. SIZE must always be specified.
3655
3656 SIZE is important for structure constructors,
3657 since trailing members may have been omitted from the constructor.
3658 It is also important for initialization of arrays from string constants
3659 since the full length of the string constant might not be wanted.
3660 It is also needed for initialization of unions, where the initializer's
3661 type is just one member, and that may not be as long as the union.
3662
3663 There a case in which we would fail to output exactly SIZE bytes:
3664 for a structure constructor that wants to produce more than SIZE bytes.
3665 But such constructors will never be generated for any possible input.
3666
3667 ALIGN is the alignment of the data in bits. */
3668
3669 void
3670 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align)
3671 {
3672 enum tree_code code;
3673 unsigned HOST_WIDE_INT thissize;
3674
3675 /* Some front-ends use constants other than the standard language-independent
3676 varieties, but which may still be output directly. Give the front-end a
3677 chance to convert EXP to a language-independent representation. */
3678 exp = lang_hooks.expand_constant (exp);
3679
3680 if (size == 0 || flag_syntax_only)
3681 return;
3682
3683 /* Eliminate any conversions since we'll be outputting the underlying
3684 constant. */
3685 while (TREE_CODE (exp) == NOP_EXPR || TREE_CODE (exp) == CONVERT_EXPR
3686 || TREE_CODE (exp) == NON_LVALUE_EXPR
3687 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
3688 exp = TREE_OPERAND (exp, 0);
3689
3690 code = TREE_CODE (TREE_TYPE (exp));
3691 thissize = int_size_in_bytes (TREE_TYPE (exp));
3692
3693 /* Allow a constructor with no elements for any data type.
3694 This means to fill the space with zeros. */
3695 if (TREE_CODE (exp) == CONSTRUCTOR && CONSTRUCTOR_ELTS (exp) == 0)
3696 {
3697 assemble_zeros (size);
3698 return;
3699 }
3700
3701 if (TREE_CODE (exp) == FDESC_EXPR)
3702 {
3703 #ifdef ASM_OUTPUT_FDESC
3704 HOST_WIDE_INT part = tree_low_cst (TREE_OPERAND (exp, 1), 0);
3705 tree decl = TREE_OPERAND (exp, 0);
3706 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
3707 #else
3708 abort ();
3709 #endif
3710 return;
3711 }
3712
3713 /* Now output the underlying data. If we've handling the padding, return.
3714 Otherwise, break and ensure SIZE is the size written. */
3715 switch (code)
3716 {
3717 case CHAR_TYPE:
3718 case BOOLEAN_TYPE:
3719 case INTEGER_TYPE:
3720 case ENUMERAL_TYPE:
3721 case POINTER_TYPE:
3722 case REFERENCE_TYPE:
3723 case OFFSET_TYPE:
3724 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
3725 EXPAND_INITIALIZER),
3726 MIN (size, thissize), align, 0))
3727 error ("initializer for integer value is too complicated");
3728 break;
3729
3730 case REAL_TYPE:
3731 if (TREE_CODE (exp) != REAL_CST)
3732 error ("initializer for floating value is not a floating constant");
3733
3734 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)), align);
3735 break;
3736
3737 case COMPLEX_TYPE:
3738 output_constant (TREE_REALPART (exp), thissize / 2, align);
3739 output_constant (TREE_IMAGPART (exp), thissize / 2,
3740 min_align (align, BITS_PER_UNIT * (thissize / 2)));
3741 break;
3742
3743 case ARRAY_TYPE:
3744 case VECTOR_TYPE:
3745 if (TREE_CODE (exp) == CONSTRUCTOR)
3746 {
3747 output_constructor (exp, size, align);
3748 return;
3749 }
3750 else if (TREE_CODE (exp) == STRING_CST)
3751 {
3752 thissize = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp),
3753 size);
3754 assemble_string (TREE_STRING_POINTER (exp), thissize);
3755 }
3756 else if (TREE_CODE (exp) == VECTOR_CST)
3757 {
3758 int elt_size;
3759 tree link;
3760 unsigned int nalign;
3761 enum machine_mode inner;
3762
3763 inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
3764 nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
3765
3766 elt_size = GET_MODE_SIZE (inner);
3767
3768 link = TREE_VECTOR_CST_ELTS (exp);
3769 output_constant (TREE_VALUE (link), elt_size, align);
3770 while ((link = TREE_CHAIN (link)) != NULL)
3771 output_constant (TREE_VALUE (link), elt_size, nalign);
3772 }
3773 else
3774 abort ();
3775 break;
3776
3777 case RECORD_TYPE:
3778 case UNION_TYPE:
3779 if (TREE_CODE (exp) == CONSTRUCTOR)
3780 output_constructor (exp, size, align);
3781 else
3782 abort ();
3783 return;
3784
3785 case SET_TYPE:
3786 if (TREE_CODE (exp) == INTEGER_CST)
3787 assemble_integer (expand_expr (exp, NULL_RTX,
3788 VOIDmode, EXPAND_INITIALIZER),
3789 thissize, align, 1);
3790 else if (TREE_CODE (exp) == CONSTRUCTOR)
3791 {
3792 unsigned char *buffer = alloca (thissize);
3793 if (get_set_constructor_bytes (exp, buffer, thissize))
3794 abort ();
3795 assemble_string ((char *) buffer, thissize);
3796 }
3797 else
3798 error ("unknown set constructor type");
3799 return;
3800
3801 case ERROR_MARK:
3802 return;
3803
3804 default:
3805 abort ();
3806 }
3807
3808 if (size > thissize)
3809 assemble_zeros (size - thissize);
3810 }
3811
3812 \f
3813 /* Subroutine of output_constructor, used for computing the size of
3814 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
3815 type with an unspecified upper bound. */
3816
3817 static unsigned HOST_WIDE_INT
3818 array_size_for_constructor (tree val)
3819 {
3820 tree max_index, i;
3821
3822 /* This code used to attempt to handle string constants that are not
3823 arrays of single-bytes, but nothing else does, so there's no point in
3824 doing it here. */
3825 if (TREE_CODE (val) == STRING_CST)
3826 return TREE_STRING_LENGTH (val);
3827
3828 max_index = NULL_TREE;
3829 for (i = CONSTRUCTOR_ELTS (val); i; i = TREE_CHAIN (i))
3830 {
3831 tree index = TREE_PURPOSE (i);
3832
3833 if (TREE_CODE (index) == RANGE_EXPR)
3834 index = TREE_OPERAND (index, 1);
3835 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
3836 max_index = index;
3837 }
3838
3839 if (max_index == NULL_TREE)
3840 return 0;
3841
3842 /* Compute the total number of array elements. */
3843 i = size_binop (MINUS_EXPR, convert (sizetype, max_index),
3844 convert (sizetype,
3845 TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)))));
3846 i = size_binop (PLUS_EXPR, i, convert (sizetype, integer_one_node));
3847
3848 /* Multiply by the array element unit size to find number of bytes. */
3849 i = size_binop (MULT_EXPR, i, TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
3850
3851 return tree_low_cst (i, 1);
3852 }
3853
3854 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
3855 Generate at least SIZE bytes, padding if necessary. */
3856
3857 static void
3858 output_constructor (tree exp, unsigned HOST_WIDE_INT size,
3859 unsigned int align)
3860 {
3861 tree type = TREE_TYPE (exp);
3862 tree link, field = 0;
3863 tree min_index = 0;
3864 /* Number of bytes output or skipped so far.
3865 In other words, current position within the constructor. */
3866 HOST_WIDE_INT total_bytes = 0;
3867 /* Nonzero means BYTE contains part of a byte, to be output. */
3868 int byte_buffer_in_use = 0;
3869 int byte = 0;
3870
3871 if (HOST_BITS_PER_WIDE_INT < BITS_PER_UNIT)
3872 abort ();
3873
3874 if (TREE_CODE (type) == RECORD_TYPE)
3875 field = TYPE_FIELDS (type);
3876
3877 if (TREE_CODE (type) == ARRAY_TYPE
3878 && TYPE_DOMAIN (type) != 0)
3879 min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (type));
3880
3881 /* As LINK goes through the elements of the constant,
3882 FIELD goes through the structure fields, if the constant is a structure.
3883 if the constant is a union, then we override this,
3884 by getting the field from the TREE_LIST element.
3885 But the constant could also be an array. Then FIELD is zero.
3886
3887 There is always a maximum of one element in the chain LINK for unions
3888 (even if the initializer in a source program incorrectly contains
3889 more one). */
3890 for (link = CONSTRUCTOR_ELTS (exp);
3891 link;
3892 link = TREE_CHAIN (link),
3893 field = field ? TREE_CHAIN (field) : 0)
3894 {
3895 tree val = TREE_VALUE (link);
3896 tree index = 0;
3897
3898 /* The element in a union constructor specifies the proper field
3899 or index. */
3900 if ((TREE_CODE (type) == RECORD_TYPE || TREE_CODE (type) == UNION_TYPE
3901 || TREE_CODE (type) == QUAL_UNION_TYPE)
3902 && TREE_PURPOSE (link) != 0)
3903 field = TREE_PURPOSE (link);
3904
3905 else if (TREE_CODE (type) == ARRAY_TYPE)
3906 index = TREE_PURPOSE (link);
3907
3908 #ifdef ASM_COMMENT_START
3909 if (field && flag_verbose_asm)
3910 fprintf (asm_out_file, "%s %s:\n",
3911 ASM_COMMENT_START,
3912 DECL_NAME (field)
3913 ? IDENTIFIER_POINTER (DECL_NAME (field))
3914 : "<anonymous>");
3915 #endif
3916
3917 /* Eliminate the marker that makes a cast not be an lvalue. */
3918 if (val != 0)
3919 STRIP_NOPS (val);
3920
3921 if (index && TREE_CODE (index) == RANGE_EXPR)
3922 {
3923 unsigned HOST_WIDE_INT fieldsize
3924 = int_size_in_bytes (TREE_TYPE (type));
3925 HOST_WIDE_INT lo_index = tree_low_cst (TREE_OPERAND (index, 0), 0);
3926 HOST_WIDE_INT hi_index = tree_low_cst (TREE_OPERAND (index, 1), 0);
3927 HOST_WIDE_INT index;
3928 unsigned int align2 = min_align (align, fieldsize * BITS_PER_UNIT);
3929
3930 for (index = lo_index; index <= hi_index; index++)
3931 {
3932 /* Output the element's initial value. */
3933 if (val == 0)
3934 assemble_zeros (fieldsize);
3935 else
3936 output_constant (val, fieldsize, align2);
3937
3938 /* Count its size. */
3939 total_bytes += fieldsize;
3940 }
3941 }
3942 else if (field == 0 || !DECL_BIT_FIELD (field))
3943 {
3944 /* An element that is not a bit-field. */
3945
3946 unsigned HOST_WIDE_INT fieldsize;
3947 /* Since this structure is static,
3948 we know the positions are constant. */
3949 HOST_WIDE_INT pos = field ? int_byte_position (field) : 0;
3950 unsigned int align2;
3951
3952 if (index != 0)
3953 pos = (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (val)), 1)
3954 * (tree_low_cst (index, 0) - tree_low_cst (min_index, 0)));
3955
3956 /* Output any buffered-up bit-fields preceding this element. */
3957 if (byte_buffer_in_use)
3958 {
3959 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
3960 total_bytes++;
3961 byte_buffer_in_use = 0;
3962 }
3963
3964 /* Advance to offset of this element.
3965 Note no alignment needed in an array, since that is guaranteed
3966 if each element has the proper size. */
3967 if ((field != 0 || index != 0) && pos != total_bytes)
3968 {
3969 assemble_zeros (pos - total_bytes);
3970 total_bytes = pos;
3971 }
3972
3973 /* Find the alignment of this element. */
3974 align2 = min_align (align, BITS_PER_UNIT * pos);
3975
3976 /* Determine size this element should occupy. */
3977 if (field)
3978 {
3979 fieldsize = 0;
3980
3981 /* If this is an array with an unspecified upper bound,
3982 the initializer determines the size. */
3983 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
3984 but we cannot do this until the deprecated support for
3985 initializing zero-length array members is removed. */
3986 if (TREE_CODE (TREE_TYPE (field)) == ARRAY_TYPE
3987 && TYPE_DOMAIN (TREE_TYPE (field))
3988 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (field))))
3989 {
3990 fieldsize = array_size_for_constructor (val);
3991 /* Given a non-empty initialization, this field had
3992 better be last. */
3993 if (fieldsize != 0 && TREE_CHAIN (field) != NULL_TREE)
3994 abort ();
3995 }
3996 else if (DECL_SIZE_UNIT (field))
3997 {
3998 /* ??? This can't be right. If the decl size overflows
3999 a host integer we will silently emit no data. */
4000 if (host_integerp (DECL_SIZE_UNIT (field), 1))
4001 fieldsize = tree_low_cst (DECL_SIZE_UNIT (field), 1);
4002 }
4003 }
4004 else
4005 fieldsize = int_size_in_bytes (TREE_TYPE (type));
4006
4007 /* Output the element's initial value. */
4008 if (val == 0)
4009 assemble_zeros (fieldsize);
4010 else
4011 output_constant (val, fieldsize, align2);
4012
4013 /* Count its size. */
4014 total_bytes += fieldsize;
4015 }
4016 else if (val != 0 && TREE_CODE (val) != INTEGER_CST)
4017 error ("invalid initial value for member %qs",
4018 IDENTIFIER_POINTER (DECL_NAME (field)));
4019 else
4020 {
4021 /* Element that is a bit-field. */
4022
4023 HOST_WIDE_INT next_offset = int_bit_position (field);
4024 HOST_WIDE_INT end_offset
4025 = (next_offset + tree_low_cst (DECL_SIZE (field), 1));
4026
4027 if (val == 0)
4028 val = integer_zero_node;
4029
4030 /* If this field does not start in this (or, next) byte,
4031 skip some bytes. */
4032 if (next_offset / BITS_PER_UNIT != total_bytes)
4033 {
4034 /* Output remnant of any bit field in previous bytes. */
4035 if (byte_buffer_in_use)
4036 {
4037 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4038 total_bytes++;
4039 byte_buffer_in_use = 0;
4040 }
4041
4042 /* If still not at proper byte, advance to there. */
4043 if (next_offset / BITS_PER_UNIT != total_bytes)
4044 {
4045 assemble_zeros (next_offset / BITS_PER_UNIT - total_bytes);
4046 total_bytes = next_offset / BITS_PER_UNIT;
4047 }
4048 }
4049
4050 if (! byte_buffer_in_use)
4051 byte = 0;
4052
4053 /* We must split the element into pieces that fall within
4054 separate bytes, and combine each byte with previous or
4055 following bit-fields. */
4056
4057 /* next_offset is the offset n fbits from the beginning of
4058 the structure to the next bit of this element to be processed.
4059 end_offset is the offset of the first bit past the end of
4060 this element. */
4061 while (next_offset < end_offset)
4062 {
4063 int this_time;
4064 int shift;
4065 HOST_WIDE_INT value;
4066 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
4067 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
4068
4069 /* Advance from byte to byte
4070 within this element when necessary. */
4071 while (next_byte != total_bytes)
4072 {
4073 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4074 total_bytes++;
4075 byte = 0;
4076 }
4077
4078 /* Number of bits we can process at once
4079 (all part of the same byte). */
4080 this_time = MIN (end_offset - next_offset,
4081 BITS_PER_UNIT - next_bit);
4082 if (BYTES_BIG_ENDIAN)
4083 {
4084 /* On big-endian machine, take the most significant bits
4085 first (of the bits that are significant)
4086 and put them into bytes from the most significant end. */
4087 shift = end_offset - next_offset - this_time;
4088
4089 /* Don't try to take a bunch of bits that cross
4090 the word boundary in the INTEGER_CST. We can
4091 only select bits from the LOW or HIGH part
4092 not from both. */
4093 if (shift < HOST_BITS_PER_WIDE_INT
4094 && shift + this_time > HOST_BITS_PER_WIDE_INT)
4095 {
4096 this_time = shift + this_time - HOST_BITS_PER_WIDE_INT;
4097 shift = HOST_BITS_PER_WIDE_INT;
4098 }
4099
4100 /* Now get the bits from the appropriate constant word. */
4101 if (shift < HOST_BITS_PER_WIDE_INT)
4102 value = TREE_INT_CST_LOW (val);
4103 else if (shift < 2 * HOST_BITS_PER_WIDE_INT)
4104 {
4105 value = TREE_INT_CST_HIGH (val);
4106 shift -= HOST_BITS_PER_WIDE_INT;
4107 }
4108 else
4109 abort ();
4110
4111 /* Get the result. This works only when:
4112 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
4113 byte |= (((value >> shift)
4114 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
4115 << (BITS_PER_UNIT - this_time - next_bit));
4116 }
4117 else
4118 {
4119 /* On little-endian machines,
4120 take first the least significant bits of the value
4121 and pack them starting at the least significant
4122 bits of the bytes. */
4123 shift = next_offset - int_bit_position (field);
4124
4125 /* Don't try to take a bunch of bits that cross
4126 the word boundary in the INTEGER_CST. We can
4127 only select bits from the LOW or HIGH part
4128 not from both. */
4129 if (shift < HOST_BITS_PER_WIDE_INT
4130 && shift + this_time > HOST_BITS_PER_WIDE_INT)
4131 this_time = (HOST_BITS_PER_WIDE_INT - shift);
4132
4133 /* Now get the bits from the appropriate constant word. */
4134 if (shift < HOST_BITS_PER_WIDE_INT)
4135 value = TREE_INT_CST_LOW (val);
4136 else if (shift < 2 * HOST_BITS_PER_WIDE_INT)
4137 {
4138 value = TREE_INT_CST_HIGH (val);
4139 shift -= HOST_BITS_PER_WIDE_INT;
4140 }
4141 else
4142 abort ();
4143
4144 /* Get the result. This works only when:
4145 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
4146 byte |= (((value >> shift)
4147 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
4148 << next_bit);
4149 }
4150
4151 next_offset += this_time;
4152 byte_buffer_in_use = 1;
4153 }
4154 }
4155 }
4156
4157 if (byte_buffer_in_use)
4158 {
4159 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4160 total_bytes++;
4161 }
4162
4163 if ((unsigned HOST_WIDE_INT)total_bytes < size)
4164 assemble_zeros (size - total_bytes);
4165 }
4166
4167 /* This TREE_LIST contains any weak symbol declarations waiting
4168 to be emitted. */
4169 static GTY(()) tree weak_decls;
4170
4171 /* Mark DECL as weak. */
4172
4173 static void
4174 mark_weak (tree decl)
4175 {
4176 DECL_WEAK (decl) = 1;
4177
4178 if (DECL_RTL_SET_P (decl)
4179 && MEM_P (DECL_RTL (decl))
4180 && XEXP (DECL_RTL (decl), 0)
4181 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
4182 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
4183 }
4184
4185 /* Merge weak status between NEWDECL and OLDDECL. */
4186
4187 void
4188 merge_weak (tree newdecl, tree olddecl)
4189 {
4190 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
4191 return;
4192
4193 if (DECL_WEAK (newdecl))
4194 {
4195 tree wd;
4196
4197 /* NEWDECL is weak, but OLDDECL is not. */
4198
4199 /* If we already output the OLDDECL, we're in trouble; we can't
4200 go back and make it weak. This error cannot caught in
4201 declare_weak because the NEWDECL and OLDDECL was not yet
4202 been merged; therefore, TREE_ASM_WRITTEN was not set. */
4203 if (TREE_ASM_WRITTEN (olddecl))
4204 error ("%Jweak declaration of %qD must precede definition",
4205 newdecl, newdecl);
4206
4207 /* If we've already generated rtl referencing OLDDECL, we may
4208 have done so in a way that will not function properly with
4209 a weak symbol. */
4210 else if (TREE_USED (olddecl)
4211 && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)))
4212 warning ("%Jweak declaration of %qD after first use results "
4213 "in unspecified behavior", newdecl, newdecl);
4214
4215 if (SUPPORTS_WEAK)
4216 {
4217 /* We put the NEWDECL on the weak_decls list at some point.
4218 Replace it with the OLDDECL. */
4219 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
4220 if (TREE_VALUE (wd) == newdecl)
4221 {
4222 TREE_VALUE (wd) = olddecl;
4223 break;
4224 }
4225 /* We may not find the entry on the list. If NEWDECL is a
4226 weak alias, then we will have already called
4227 globalize_decl to remove the entry; in that case, we do
4228 not need to do anything. */
4229 }
4230
4231 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
4232 mark_weak (olddecl);
4233 }
4234 else
4235 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
4236 weak. Just update NEWDECL to indicate that it's weak too. */
4237 mark_weak (newdecl);
4238 }
4239
4240 /* Declare DECL to be a weak symbol. */
4241
4242 void
4243 declare_weak (tree decl)
4244 {
4245 if (! TREE_PUBLIC (decl))
4246 error ("%Jweak declaration of %qD must be public", decl, decl);
4247 else if (TREE_CODE (decl) == FUNCTION_DECL && TREE_ASM_WRITTEN (decl))
4248 error ("%Jweak declaration of %qD must precede definition", decl, decl);
4249 else if (SUPPORTS_WEAK)
4250 {
4251 if (! DECL_WEAK (decl))
4252 weak_decls = tree_cons (NULL, decl, weak_decls);
4253 }
4254 else
4255 warning ("%Jweak declaration of %qD not supported", decl, decl);
4256
4257 mark_weak (decl);
4258 }
4259
4260 /* Emit any pending weak declarations. */
4261
4262 void
4263 weak_finish (void)
4264 {
4265 tree t;
4266
4267 for (t = weak_decls; t; t = TREE_CHAIN (t))
4268 {
4269 tree decl = TREE_VALUE (t);
4270 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
4271 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
4272 #endif
4273
4274 if (! TREE_USED (decl))
4275 continue;
4276
4277 #ifdef ASM_WEAKEN_DECL
4278 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
4279 #else
4280 #ifdef ASM_WEAKEN_LABEL
4281 ASM_WEAKEN_LABEL (asm_out_file, name);
4282 #else
4283 #ifdef ASM_OUTPUT_WEAK_ALIAS
4284 warning ("only weak aliases are supported in this configuration");
4285 return;
4286 #endif
4287 #endif
4288 #endif
4289 }
4290 }
4291
4292 /* Emit the assembly bits to indicate that DECL is globally visible. */
4293
4294 static void
4295 globalize_decl (tree decl)
4296 {
4297 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
4298
4299 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
4300 if (DECL_WEAK (decl))
4301 {
4302 tree *p, t;
4303
4304 #ifdef ASM_WEAKEN_DECL
4305 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
4306 #else
4307 ASM_WEAKEN_LABEL (asm_out_file, name);
4308 #endif
4309
4310 /* Remove this function from the pending weak list so that
4311 we do not emit multiple .weak directives for it. */
4312 for (p = &weak_decls; (t = *p) ; )
4313 {
4314 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
4315 *p = TREE_CHAIN (t);
4316 else
4317 p = &TREE_CHAIN (t);
4318 }
4319 return;
4320 }
4321 #elif defined(ASM_MAKE_LABEL_LINKONCE)
4322 if (DECL_ONE_ONLY (decl))
4323 ASM_MAKE_LABEL_LINKONCE (asm_out_file, name);
4324 #endif
4325
4326 targetm.asm_out.globalize_label (asm_out_file, name);
4327 }
4328
4329 /* Emit an assembler directive to make the symbol for DECL an alias to
4330 the symbol for TARGET. */
4331
4332 void
4333 assemble_alias (tree decl, tree target ATTRIBUTE_UNUSED)
4334 {
4335 const char *name;
4336
4337 /* We must force creation of DECL_RTL for debug info generation, even though
4338 we don't use it here. */
4339 make_decl_rtl (decl);
4340
4341 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
4342
4343 #ifdef ASM_OUTPUT_DEF
4344 /* Make name accessible from other files, if appropriate. */
4345
4346 if (TREE_PUBLIC (decl))
4347 {
4348 globalize_decl (decl);
4349 maybe_assemble_visibility (decl);
4350 }
4351
4352 #ifdef ASM_OUTPUT_DEF_FROM_DECLS
4353 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
4354 #else
4355 ASM_OUTPUT_DEF (asm_out_file, name, IDENTIFIER_POINTER (target));
4356 #endif
4357 #else /* !ASM_OUTPUT_DEF */
4358 #if defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
4359 if (DECL_WEAK (decl))
4360 {
4361 tree *p, t;
4362 #ifdef ASM_WEAKEN_DECL
4363 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
4364 #else
4365 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
4366 #endif
4367 /* Remove this function from the pending weak list so that
4368 we do not emit multiple .weak directives for it. */
4369 for (p = &weak_decls; (t = *p) ; )
4370 if (DECL_ASSEMBLER_NAME (decl)
4371 == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
4372 *p = TREE_CHAIN (t);
4373 else
4374 p = &TREE_CHAIN (t);
4375 }
4376 else
4377 warning ("only weak aliases are supported in this configuration");
4378
4379 #else
4380 warning ("alias definitions not supported in this configuration; ignored");
4381 #endif
4382 #endif
4383
4384 TREE_USED (decl) = 1;
4385 TREE_ASM_WRITTEN (decl) = 1;
4386 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
4387 }
4388
4389 /* Emit an assembler directive to set symbol for DECL visibility to
4390 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
4391
4392 void
4393 default_assemble_visibility (tree decl, int vis)
4394 {
4395 static const char * const visibility_types[] = {
4396 NULL, "internal", "hidden", "protected"
4397 };
4398
4399 const char *name, *type;
4400
4401 name = (IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)));
4402 type = visibility_types[vis];
4403
4404 #ifdef HAVE_GAS_HIDDEN
4405 fprintf (asm_out_file, "\t.%s\t", type);
4406 assemble_name (asm_out_file, name);
4407 fprintf (asm_out_file, "\n");
4408 #else
4409 warning ("visibility attribute not supported in this configuration; ignored");
4410 #endif
4411 }
4412
4413 /* A helper function to call assemble_visibility when needed for a decl. */
4414
4415 static void
4416 maybe_assemble_visibility (tree decl)
4417 {
4418 enum symbol_visibility vis = DECL_VISIBILITY (decl);
4419
4420 if (vis != VISIBILITY_DEFAULT)
4421 targetm.asm_out.visibility (decl, vis);
4422 }
4423
4424 /* Returns 1 if the target configuration supports defining public symbols
4425 so that one of them will be chosen at link time instead of generating a
4426 multiply-defined symbol error, whether through the use of weak symbols or
4427 a target-specific mechanism for having duplicates discarded. */
4428
4429 int
4430 supports_one_only (void)
4431 {
4432 if (SUPPORTS_ONE_ONLY)
4433 return 1;
4434 return SUPPORTS_WEAK;
4435 }
4436
4437 /* Set up DECL as a public symbol that can be defined in multiple
4438 translation units without generating a linker error. */
4439
4440 void
4441 make_decl_one_only (tree decl)
4442 {
4443 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != FUNCTION_DECL)
4444 abort ();
4445
4446 TREE_PUBLIC (decl) = 1;
4447
4448 if (SUPPORTS_ONE_ONLY)
4449 {
4450 #ifdef MAKE_DECL_ONE_ONLY
4451 MAKE_DECL_ONE_ONLY (decl);
4452 #endif
4453 DECL_ONE_ONLY (decl) = 1;
4454 }
4455 else if (TREE_CODE (decl) == VAR_DECL
4456 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node))
4457 DECL_COMMON (decl) = 1;
4458 else if (SUPPORTS_WEAK)
4459 DECL_WEAK (decl) = 1;
4460 else
4461 abort ();
4462 }
4463
4464 void
4465 init_varasm_once (void)
4466 {
4467 in_named_htab = htab_create_ggc (31, in_named_entry_hash,
4468 in_named_entry_eq, NULL);
4469 const_desc_htab = htab_create_ggc (1009, const_desc_hash,
4470 const_desc_eq, NULL);
4471
4472 const_alias_set = new_alias_set ();
4473 }
4474
4475 enum tls_model
4476 decl_tls_model (tree decl)
4477 {
4478 enum tls_model kind;
4479 tree attr = lookup_attribute ("tls_model", DECL_ATTRIBUTES (decl));
4480 bool is_local;
4481
4482 if (attr)
4483 {
4484 attr = TREE_VALUE (TREE_VALUE (attr));
4485 if (TREE_CODE (attr) != STRING_CST)
4486 abort ();
4487 if (!strcmp (TREE_STRING_POINTER (attr), "local-exec"))
4488 kind = TLS_MODEL_LOCAL_EXEC;
4489 else if (!strcmp (TREE_STRING_POINTER (attr), "initial-exec"))
4490 kind = TLS_MODEL_INITIAL_EXEC;
4491 else if (!strcmp (TREE_STRING_POINTER (attr), "local-dynamic"))
4492 kind = optimize ? TLS_MODEL_LOCAL_DYNAMIC : TLS_MODEL_GLOBAL_DYNAMIC;
4493 else if (!strcmp (TREE_STRING_POINTER (attr), "global-dynamic"))
4494 kind = TLS_MODEL_GLOBAL_DYNAMIC;
4495 else
4496 abort ();
4497 return kind;
4498 }
4499
4500 is_local = targetm.binds_local_p (decl);
4501 if (!flag_pic)
4502 {
4503 if (is_local)
4504 kind = TLS_MODEL_LOCAL_EXEC;
4505 else
4506 kind = TLS_MODEL_INITIAL_EXEC;
4507 }
4508 /* Local dynamic is inefficient when we're not combining the
4509 parts of the address. */
4510 else if (optimize && is_local)
4511 kind = TLS_MODEL_LOCAL_DYNAMIC;
4512 else
4513 kind = TLS_MODEL_GLOBAL_DYNAMIC;
4514 if (kind < flag_tls_default)
4515 kind = flag_tls_default;
4516
4517 return kind;
4518 }
4519
4520 /* Select a set of attributes for section NAME based on the properties
4521 of DECL and whether or not RELOC indicates that DECL's initializer
4522 might contain runtime relocations.
4523
4524 We make the section read-only and executable for a function decl,
4525 read-only for a const data decl, and writable for a non-const data decl. */
4526
4527 unsigned int
4528 default_section_type_flags (tree decl, const char *name, int reloc)
4529 {
4530 return default_section_type_flags_1 (decl, name, reloc, flag_pic);
4531 }
4532
4533 unsigned int
4534 default_section_type_flags_1 (tree decl, const char *name, int reloc,
4535 int shlib)
4536 {
4537 unsigned int flags;
4538
4539 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
4540 flags = SECTION_CODE;
4541 else if (decl && decl_readonly_section_1 (decl, reloc, shlib))
4542 flags = 0;
4543 else if (unlikely_text_section_name
4544 && strcmp (name, unlikely_text_section_name) == 0)
4545 flags = SECTION_CODE;
4546 else
4547 flags = SECTION_WRITE;
4548
4549 if (decl && DECL_ONE_ONLY (decl))
4550 flags |= SECTION_LINKONCE;
4551
4552 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl))
4553 flags |= SECTION_TLS | SECTION_WRITE;
4554
4555 if (strcmp (name, ".bss") == 0
4556 || strncmp (name, ".bss.", 5) == 0
4557 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
4558 || strcmp (name, ".sbss") == 0
4559 || strncmp (name, ".sbss.", 6) == 0
4560 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0
4561 || strcmp (name, ".tbss") == 0
4562 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
4563 flags |= SECTION_BSS;
4564
4565 if (strcmp (name, ".tdata") == 0
4566 || strcmp (name, ".tbss") == 0
4567 || strncmp (name, ".gnu.linkonce.td.", 17) == 0
4568 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
4569 flags |= SECTION_TLS;
4570
4571 /* These three sections have special ELF types. They are neither
4572 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
4573 want to print a section type (@progbits or @nobits). If someone
4574 is silly enough to emit code or TLS variables to one of these
4575 sections, then don't handle them specially. */
4576 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
4577 && (strcmp (name, ".init_array") == 0
4578 || strcmp (name, ".fini_array") == 0
4579 || strcmp (name, ".preinit_array") == 0))
4580 flags |= SECTION_NOTYPE;
4581
4582 return flags;
4583 }
4584
4585 /* Output assembly to switch to section NAME with attribute FLAGS.
4586 Four variants for common object file formats. */
4587
4588 void
4589 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
4590 unsigned int flags ATTRIBUTE_UNUSED,
4591 tree decl ATTRIBUTE_UNUSED)
4592 {
4593 /* Some object formats don't support named sections at all. The
4594 front-end should already have flagged this as an error. */
4595 abort ();
4596 }
4597
4598 void
4599 default_elf_asm_named_section (const char *name, unsigned int flags,
4600 tree decl ATTRIBUTE_UNUSED)
4601 {
4602 char flagchars[10], *f = flagchars;
4603
4604 /* If we have already declared this section, we can use an
4605 abbreviated form to switch back to it -- unless this section is
4606 part of a COMDAT groups, in which case GAS requires the full
4607 declaration every time. */
4608 if (!(HAVE_GAS_COMDAT_GROUP && (flags & SECTION_LINKONCE))
4609 && ! named_section_first_declaration (name))
4610 {
4611 fprintf (asm_out_file, "\t.section\t%s\n", name);
4612 return;
4613 }
4614
4615 if (!(flags & SECTION_DEBUG))
4616 *f++ = 'a';
4617 if (flags & SECTION_WRITE)
4618 *f++ = 'w';
4619 if (flags & SECTION_CODE)
4620 *f++ = 'x';
4621 if (flags & SECTION_SMALL)
4622 *f++ = 's';
4623 if (flags & SECTION_MERGE)
4624 *f++ = 'M';
4625 if (flags & SECTION_STRINGS)
4626 *f++ = 'S';
4627 if (flags & SECTION_TLS)
4628 *f++ = 'T';
4629 if (HAVE_GAS_COMDAT_GROUP && (flags & SECTION_LINKONCE))
4630 *f++ = 'G';
4631 *f = '\0';
4632
4633 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
4634
4635 if (!(flags & SECTION_NOTYPE))
4636 {
4637 const char *type;
4638 const char *format;
4639
4640 if (flags & SECTION_BSS)
4641 type = "nobits";
4642 else
4643 type = "progbits";
4644
4645 format = ",@%s";
4646 #ifdef ASM_COMMENT_START
4647 /* On platforms that use "@" as the assembly comment character,
4648 use "%" instead. */
4649 if (strcmp (ASM_COMMENT_START, "@") == 0)
4650 format = ",%%%s";
4651 #endif
4652 fprintf (asm_out_file, format, type);
4653
4654 if (flags & SECTION_ENTSIZE)
4655 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
4656 if (HAVE_GAS_COMDAT_GROUP && (flags & SECTION_LINKONCE))
4657 fprintf (asm_out_file, ",%s,comdat",
4658 lang_hooks.decls.comdat_group (decl));
4659 }
4660
4661 putc ('\n', asm_out_file);
4662 }
4663
4664 void
4665 default_coff_asm_named_section (const char *name, unsigned int flags,
4666 tree decl ATTRIBUTE_UNUSED)
4667 {
4668 char flagchars[8], *f = flagchars;
4669
4670 if (flags & SECTION_WRITE)
4671 *f++ = 'w';
4672 if (flags & SECTION_CODE)
4673 *f++ = 'x';
4674 *f = '\0';
4675
4676 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
4677 }
4678
4679 void
4680 default_pe_asm_named_section (const char *name, unsigned int flags,
4681 tree decl)
4682 {
4683 default_coff_asm_named_section (name, flags, decl);
4684
4685 if (flags & SECTION_LINKONCE)
4686 {
4687 /* Functions may have been compiled at various levels of
4688 optimization so we can't use `same_size' here.
4689 Instead, have the linker pick one. */
4690 fprintf (asm_out_file, "\t.linkonce %s\n",
4691 (flags & SECTION_CODE ? "discard" : "same_size"));
4692 }
4693 }
4694 \f
4695 /* The lame default section selector. */
4696
4697 void
4698 default_select_section (tree decl, int reloc,
4699 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
4700 {
4701 bool readonly = false;
4702
4703 if (DECL_P (decl))
4704 {
4705 if (decl_readonly_section (decl, reloc))
4706 readonly = true;
4707 }
4708 else if (TREE_CODE (decl) == CONSTRUCTOR)
4709 {
4710 if (! ((flag_pic && reloc)
4711 || !TREE_READONLY (decl)
4712 || TREE_SIDE_EFFECTS (decl)
4713 || !TREE_CONSTANT (decl)))
4714 readonly = true;
4715 }
4716 else if (TREE_CODE (decl) == STRING_CST)
4717 readonly = true;
4718 else if (! (flag_pic && reloc))
4719 readonly = true;
4720
4721 if (readonly)
4722 readonly_data_section ();
4723 else
4724 data_section ();
4725 }
4726
4727 /* A helper function for default_elf_select_section and
4728 default_elf_unique_section. Categorizes the DECL. */
4729
4730 enum section_category
4731 {
4732 SECCAT_TEXT,
4733
4734 SECCAT_RODATA,
4735 SECCAT_RODATA_MERGE_STR,
4736 SECCAT_RODATA_MERGE_STR_INIT,
4737 SECCAT_RODATA_MERGE_CONST,
4738 SECCAT_SRODATA,
4739
4740 SECCAT_DATA,
4741
4742 /* To optimize loading of shared programs, define following subsections
4743 of data section:
4744 _REL Contains data that has relocations, so they get grouped
4745 together and dynamic linker will visit fewer pages in memory.
4746 _RO Contains data that is otherwise read-only. This is useful
4747 with prelinking as most relocations won't be dynamically
4748 linked and thus stay read only.
4749 _LOCAL Marks data containing relocations only to local objects.
4750 These relocations will get fully resolved by prelinking. */
4751 SECCAT_DATA_REL,
4752 SECCAT_DATA_REL_LOCAL,
4753 SECCAT_DATA_REL_RO,
4754 SECCAT_DATA_REL_RO_LOCAL,
4755
4756 SECCAT_SDATA,
4757 SECCAT_TDATA,
4758
4759 SECCAT_BSS,
4760 SECCAT_SBSS,
4761 SECCAT_TBSS
4762 };
4763
4764 static enum section_category
4765 categorize_decl_for_section (tree, int, int);
4766
4767 static enum section_category
4768 categorize_decl_for_section (tree decl, int reloc, int shlib)
4769 {
4770 enum section_category ret;
4771
4772 if (TREE_CODE (decl) == FUNCTION_DECL)
4773 return SECCAT_TEXT;
4774 else if (TREE_CODE (decl) == STRING_CST)
4775 {
4776 if (flag_mudflap) /* or !flag_merge_constants */
4777 return SECCAT_RODATA;
4778 else
4779 return SECCAT_RODATA_MERGE_STR;
4780 }
4781 else if (TREE_CODE (decl) == VAR_DECL)
4782 {
4783 if (DECL_INITIAL (decl) == NULL
4784 || DECL_INITIAL (decl) == error_mark_node
4785 || (flag_zero_initialized_in_bss
4786 /* Leave constant zeroes in .rodata so they can be shared. */
4787 && !TREE_READONLY (decl)
4788 && initializer_zerop (DECL_INITIAL (decl))))
4789 ret = SECCAT_BSS;
4790 else if (! TREE_READONLY (decl)
4791 || TREE_SIDE_EFFECTS (decl)
4792 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
4793 {
4794 if (shlib && (reloc & 2))
4795 ret = SECCAT_DATA_REL;
4796 else if (shlib && reloc)
4797 ret = SECCAT_DATA_REL_LOCAL;
4798 else
4799 ret = SECCAT_DATA;
4800 }
4801 else if (shlib && (reloc & 2))
4802 ret = SECCAT_DATA_REL_RO;
4803 else if (shlib && reloc)
4804 ret = SECCAT_DATA_REL_RO_LOCAL;
4805 else if (reloc || flag_merge_constants < 2)
4806 /* C and C++ don't allow different variables to share the same
4807 location. -fmerge-all-constants allows even that (at the
4808 expense of not conforming). */
4809 ret = SECCAT_RODATA;
4810 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
4811 ret = SECCAT_RODATA_MERGE_STR_INIT;
4812 else
4813 ret = SECCAT_RODATA_MERGE_CONST;
4814 }
4815 else if (TREE_CODE (decl) == CONSTRUCTOR)
4816 {
4817 if ((shlib && reloc)
4818 || TREE_SIDE_EFFECTS (decl)
4819 || ! TREE_CONSTANT (decl))
4820 ret = SECCAT_DATA;
4821 else
4822 ret = SECCAT_RODATA;
4823 }
4824 else
4825 ret = SECCAT_RODATA;
4826
4827 /* There are no read-only thread-local sections. */
4828 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl))
4829 {
4830 /* Note that this would be *just* SECCAT_BSS, except that there's
4831 no concept of a read-only thread-local-data section. */
4832 if (ret == SECCAT_BSS
4833 || (flag_zero_initialized_in_bss
4834 && initializer_zerop (DECL_INITIAL (decl))))
4835 ret = SECCAT_TBSS;
4836 else
4837 ret = SECCAT_TDATA;
4838 }
4839
4840 /* If the target uses small data sections, select it. */
4841 else if (targetm.in_small_data_p (decl))
4842 {
4843 if (ret == SECCAT_BSS)
4844 ret = SECCAT_SBSS;
4845 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
4846 ret = SECCAT_SRODATA;
4847 else
4848 ret = SECCAT_SDATA;
4849 }
4850
4851 return ret;
4852 }
4853
4854 bool
4855 decl_readonly_section (tree decl, int reloc)
4856 {
4857 return decl_readonly_section_1 (decl, reloc, flag_pic);
4858 }
4859
4860 bool
4861 decl_readonly_section_1 (tree decl, int reloc, int shlib)
4862 {
4863 switch (categorize_decl_for_section (decl, reloc, shlib))
4864 {
4865 case SECCAT_RODATA:
4866 case SECCAT_RODATA_MERGE_STR:
4867 case SECCAT_RODATA_MERGE_STR_INIT:
4868 case SECCAT_RODATA_MERGE_CONST:
4869 case SECCAT_SRODATA:
4870 return true;
4871 break;
4872 default:
4873 return false;
4874 break;
4875 }
4876 }
4877
4878 /* Select a section based on the above categorization. */
4879
4880 void
4881 default_elf_select_section (tree decl, int reloc,
4882 unsigned HOST_WIDE_INT align)
4883 {
4884 default_elf_select_section_1 (decl, reloc, align, flag_pic);
4885 }
4886
4887 void
4888 default_elf_select_section_1 (tree decl, int reloc,
4889 unsigned HOST_WIDE_INT align, int shlib)
4890 {
4891 switch (categorize_decl_for_section (decl, reloc, shlib))
4892 {
4893 case SECCAT_TEXT:
4894 /* We're not supposed to be called on FUNCTION_DECLs. */
4895 abort ();
4896 case SECCAT_RODATA:
4897 readonly_data_section ();
4898 break;
4899 case SECCAT_RODATA_MERGE_STR:
4900 mergeable_string_section (decl, align, 0);
4901 break;
4902 case SECCAT_RODATA_MERGE_STR_INIT:
4903 mergeable_string_section (DECL_INITIAL (decl), align, 0);
4904 break;
4905 case SECCAT_RODATA_MERGE_CONST:
4906 mergeable_constant_section (DECL_MODE (decl), align, 0);
4907 break;
4908 case SECCAT_SRODATA:
4909 named_section (NULL_TREE, ".sdata2", reloc);
4910 break;
4911 case SECCAT_DATA:
4912 data_section ();
4913 break;
4914 case SECCAT_DATA_REL:
4915 named_section (NULL_TREE, ".data.rel", reloc);
4916 break;
4917 case SECCAT_DATA_REL_LOCAL:
4918 named_section (NULL_TREE, ".data.rel.local", reloc);
4919 break;
4920 case SECCAT_DATA_REL_RO:
4921 named_section (NULL_TREE, ".data.rel.ro", reloc);
4922 break;
4923 case SECCAT_DATA_REL_RO_LOCAL:
4924 named_section (NULL_TREE, ".data.rel.ro.local", reloc);
4925 break;
4926 case SECCAT_SDATA:
4927 named_section (NULL_TREE, ".sdata", reloc);
4928 break;
4929 case SECCAT_TDATA:
4930 named_section (NULL_TREE, ".tdata", reloc);
4931 break;
4932 case SECCAT_BSS:
4933 #ifdef BSS_SECTION_ASM_OP
4934 bss_section ();
4935 #else
4936 named_section (NULL_TREE, ".bss", reloc);
4937 #endif
4938 break;
4939 case SECCAT_SBSS:
4940 named_section (NULL_TREE, ".sbss", reloc);
4941 break;
4942 case SECCAT_TBSS:
4943 named_section (NULL_TREE, ".tbss", reloc);
4944 break;
4945 default:
4946 abort ();
4947 }
4948 }
4949
4950 /* Construct a unique section name based on the decl name and the
4951 categorization performed above. */
4952
4953 void
4954 default_unique_section (tree decl, int reloc)
4955 {
4956 default_unique_section_1 (decl, reloc, flag_pic);
4957 }
4958
4959 void
4960 default_unique_section_1 (tree decl, int reloc, int shlib)
4961 {
4962 bool one_only = DECL_ONE_ONLY (decl);
4963 const char *prefix, *name;
4964 size_t nlen, plen;
4965 char *string;
4966
4967 switch (categorize_decl_for_section (decl, reloc, shlib))
4968 {
4969 case SECCAT_TEXT:
4970 prefix = one_only ? ".gnu.linkonce.t." : ".text.";
4971 break;
4972 case SECCAT_RODATA:
4973 case SECCAT_RODATA_MERGE_STR:
4974 case SECCAT_RODATA_MERGE_STR_INIT:
4975 case SECCAT_RODATA_MERGE_CONST:
4976 prefix = one_only ? ".gnu.linkonce.r." : ".rodata.";
4977 break;
4978 case SECCAT_SRODATA:
4979 prefix = one_only ? ".gnu.linkonce.s2." : ".sdata2.";
4980 break;
4981 case SECCAT_DATA:
4982 case SECCAT_DATA_REL:
4983 case SECCAT_DATA_REL_LOCAL:
4984 case SECCAT_DATA_REL_RO:
4985 case SECCAT_DATA_REL_RO_LOCAL:
4986 prefix = one_only ? ".gnu.linkonce.d." : ".data.";
4987 break;
4988 case SECCAT_SDATA:
4989 prefix = one_only ? ".gnu.linkonce.s." : ".sdata.";
4990 break;
4991 case SECCAT_BSS:
4992 prefix = one_only ? ".gnu.linkonce.b." : ".bss.";
4993 break;
4994 case SECCAT_SBSS:
4995 prefix = one_only ? ".gnu.linkonce.sb." : ".sbss.";
4996 break;
4997 case SECCAT_TDATA:
4998 prefix = one_only ? ".gnu.linkonce.td." : ".tdata.";
4999 break;
5000 case SECCAT_TBSS:
5001 prefix = one_only ? ".gnu.linkonce.tb." : ".tbss.";
5002 break;
5003 default:
5004 abort ();
5005 }
5006 plen = strlen (prefix);
5007
5008 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5009 name = targetm.strip_name_encoding (name);
5010 nlen = strlen (name);
5011
5012 string = alloca (nlen + plen + 1);
5013 memcpy (string, prefix, plen);
5014 memcpy (string + plen, name, nlen + 1);
5015
5016 DECL_SECTION_NAME (decl) = build_string (nlen + plen, string);
5017 }
5018
5019 void
5020 default_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
5021 rtx x,
5022 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
5023 {
5024 if (flag_pic)
5025 switch (GET_CODE (x))
5026 {
5027 case CONST:
5028 case SYMBOL_REF:
5029 case LABEL_REF:
5030 data_section ();
5031 return;
5032
5033 default:
5034 break;
5035 }
5036
5037 readonly_data_section ();
5038 }
5039
5040 void
5041 default_elf_select_rtx_section (enum machine_mode mode, rtx x,
5042 unsigned HOST_WIDE_INT align)
5043 {
5044 /* ??? Handle small data here somehow. */
5045
5046 if (flag_pic)
5047 switch (GET_CODE (x))
5048 {
5049 case CONST:
5050 case SYMBOL_REF:
5051 named_section (NULL_TREE, ".data.rel.ro", 3);
5052 return;
5053
5054 case LABEL_REF:
5055 named_section (NULL_TREE, ".data.rel.ro.local", 1);
5056 return;
5057
5058 default:
5059 break;
5060 }
5061
5062 mergeable_constant_section (mode, align, 0);
5063 }
5064
5065 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
5066
5067 void
5068 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
5069 {
5070 rtx symbol;
5071 int flags;
5072
5073 /* Careful not to prod global register variables. */
5074 if (!MEM_P (rtl))
5075 return;
5076 symbol = XEXP (rtl, 0);
5077 if (GET_CODE (symbol) != SYMBOL_REF)
5078 return;
5079
5080 flags = 0;
5081 if (TREE_CODE (decl) == FUNCTION_DECL)
5082 flags |= SYMBOL_FLAG_FUNCTION;
5083 if (targetm.binds_local_p (decl))
5084 flags |= SYMBOL_FLAG_LOCAL;
5085 if (targetm.in_small_data_p (decl))
5086 flags |= SYMBOL_FLAG_SMALL;
5087 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl))
5088 flags |= decl_tls_model (decl) << SYMBOL_FLAG_TLS_SHIFT;
5089 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
5090 being PUBLIC, the thing *must* be defined in this translation unit.
5091 Prevent this buglet from being propagated into rtl code as well. */
5092 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
5093 flags |= SYMBOL_FLAG_EXTERNAL;
5094
5095 SYMBOL_REF_FLAGS (symbol) = flags;
5096 }
5097
5098 /* By default, we do nothing for encode_section_info, so we need not
5099 do anything but discard the '*' marker. */
5100
5101 const char *
5102 default_strip_name_encoding (const char *str)
5103 {
5104 return str + (*str == '*');
5105 }
5106
5107 /* Assume ELF-ish defaults, since that's pretty much the most liberal
5108 wrt cross-module name binding. */
5109
5110 bool
5111 default_binds_local_p (tree exp)
5112 {
5113 return default_binds_local_p_1 (exp, flag_shlib);
5114 }
5115
5116 bool
5117 default_binds_local_p_1 (tree exp, int shlib)
5118 {
5119 bool local_p;
5120
5121 /* A non-decl is an entry in the constant pool. */
5122 if (!DECL_P (exp))
5123 local_p = true;
5124 /* Static variables are always local. */
5125 else if (! TREE_PUBLIC (exp))
5126 local_p = true;
5127 /* A variable is local if the user explicitly tells us so. */
5128 else if (DECL_VISIBILITY_SPECIFIED (exp) && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
5129 local_p = true;
5130 /* Otherwise, variables defined outside this object may not be local. */
5131 else if (DECL_EXTERNAL (exp))
5132 local_p = false;
5133 /* Linkonce and weak data are never local. */
5134 else if (DECL_ONE_ONLY (exp) || DECL_WEAK (exp))
5135 local_p = false;
5136 /* If none of the above and visibility is not default, make local. */
5137 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
5138 local_p = true;
5139 /* If PIC, then assume that any global name can be overridden by
5140 symbols resolved from other modules. */
5141 else if (shlib)
5142 local_p = false;
5143 /* Uninitialized COMMON variable may be unified with symbols
5144 resolved from other modules. */
5145 else if (DECL_COMMON (exp)
5146 && (DECL_INITIAL (exp) == NULL
5147 || DECL_INITIAL (exp) == error_mark_node))
5148 local_p = false;
5149 /* Otherwise we're left with initialized (or non-common) global data
5150 which is of necessity defined locally. */
5151 else
5152 local_p = true;
5153
5154 return local_p;
5155 }
5156
5157 /* Determine whether or not a pointer mode is valid. Assume defaults
5158 of ptr_mode or Pmode - can be overridden. */
5159 bool
5160 default_valid_pointer_mode (enum machine_mode mode)
5161 {
5162 return (mode == ptr_mode || mode == Pmode);
5163 }
5164
5165 /* Default function to output code that will globalize a label. A
5166 target must define GLOBAL_ASM_OP or provide it's own function to
5167 globalize a label. */
5168 #ifdef GLOBAL_ASM_OP
5169 void
5170 default_globalize_label (FILE * stream, const char *name)
5171 {
5172 fputs (GLOBAL_ASM_OP, stream);
5173 assemble_name (stream, name);
5174 putc ('\n', stream);
5175 }
5176 #endif /* GLOBAL_ASM_OP */
5177
5178 /* Default function to output a label for unwind information. The
5179 default is to do nothing. A target that needs nonlocal labels for
5180 unwind information must provide its own function to do this. */
5181 void
5182 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
5183 tree decl ATTRIBUTE_UNUSED,
5184 int for_eh ATTRIBUTE_UNUSED,
5185 int empty ATTRIBUTE_UNUSED)
5186 {
5187 }
5188
5189 /* This is how to output an internal numbered label where PREFIX is
5190 the class of label and LABELNO is the number within the class. */
5191
5192 void
5193 default_internal_label (FILE *stream, const char *prefix,
5194 unsigned long labelno)
5195 {
5196 char *const buf = alloca (40 + strlen (prefix));
5197 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
5198 ASM_OUTPUT_LABEL (stream, buf);
5199 }
5200
5201 /* This is the default behavior at the beginning of a file. It's
5202 controlled by two other target-hook toggles. */
5203 void
5204 default_file_start (void)
5205 {
5206 if (targetm.file_start_app_off && !flag_verbose_asm)
5207 fputs (ASM_APP_OFF, asm_out_file);
5208
5209 if (targetm.file_start_file_directive)
5210 output_file_directive (asm_out_file, main_input_filename);
5211 }
5212
5213 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
5214 which emits a special section directive used to indicate whether or
5215 not this object file needs an executable stack. This is primarily
5216 a GNU extension to ELF but could be used on other targets. */
5217
5218 int trampolines_created;
5219
5220 void
5221 file_end_indicate_exec_stack (void)
5222 {
5223 unsigned int flags = SECTION_DEBUG;
5224 if (trampolines_created)
5225 flags |= SECTION_CODE;
5226
5227 named_section_flags (".note.GNU-stack", flags);
5228 }
5229
5230 #include "gt-varasm.h"