varasm.c (unlikely_text_section): Use assemble_align instead of ASM_OUTPUT_ALIGN.
[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 "cgraph.h"
52 #include "cfglayout.h"
53
54 #ifdef XCOFF_DEBUGGING_INFO
55 #include "xcoffout.h" /* Needed for external data
56 declarations for e.g. AIX 4.x. */
57 #endif
58
59 #ifndef TRAMPOLINE_ALIGNMENT
60 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
61 #endif
62
63 #ifndef ASM_STABS_OP
64 #define ASM_STABS_OP "\t.stabs\t"
65 #endif
66
67 /* The (assembler) name of the first globally-visible object output. */
68 const char *first_global_object_name;
69 const char *weak_global_object_name;
70
71 struct addr_const;
72 struct constant_descriptor_rtx;
73 struct rtx_constant_pool;
74
75 struct varasm_status GTY(())
76 {
77 /* If we're using a per-function constant pool, this is it. */
78 struct rtx_constant_pool *pool;
79
80 /* Number of tree-constants deferred during the expansion of this
81 function. */
82 unsigned int deferred_constants;
83 };
84
85 #define n_deferred_constants (cfun->varasm->deferred_constants)
86
87 /* Number for making the label on the next
88 constant that is stored in memory. */
89
90 static GTY(()) int const_labelno;
91
92 /* Carry information from ASM_DECLARE_OBJECT_NAME
93 to ASM_FINISH_DECLARE_OBJECT. */
94
95 int size_directive_output;
96
97 /* The last decl for which assemble_variable was called,
98 if it did ASM_DECLARE_OBJECT_NAME.
99 If the last call to assemble_variable didn't do that,
100 this holds 0. */
101
102 tree last_assemble_variable_decl;
103
104 /* The following global variable indicates if the section label for the
105 "cold" section of code has been output yet to the assembler. The
106 label is useful when running gdb. This is part of the optimization that
107 partitions hot and cold basic blocks into separate sections of the .o
108 file. */
109
110 bool unlikely_section_label_printed = false;
111
112 /* RTX_UNCHANGING_P in a MEM can mean it is stored into, for initialization.
113 So giving constant the alias set for the type will allow such
114 initializations to appear to conflict with the load of the constant. We
115 avoid this by giving all constants an alias set for just constants.
116 Since there will be no stores to that alias set, nothing will ever
117 conflict with them. */
118
119 static HOST_WIDE_INT const_alias_set;
120
121 static const char *strip_reg_name (const char *);
122 static int contains_pointers_p (tree);
123 #ifdef ASM_OUTPUT_EXTERNAL
124 static bool incorporeal_function_p (tree);
125 #endif
126 static void decode_addr_const (tree, struct addr_const *);
127 static hashval_t const_desc_hash (const void *);
128 static int const_desc_eq (const void *, const void *);
129 static hashval_t const_hash_1 (const tree);
130 static int compare_constant (const tree, const tree);
131 static tree copy_constant (tree);
132 static void output_constant_def_contents (rtx);
133 static void output_addressed_constants (tree);
134 static unsigned HOST_WIDE_INT array_size_for_constructor (tree);
135 static unsigned min_align (unsigned, unsigned);
136 static void output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int);
137 static void globalize_decl (tree);
138 static void maybe_assemble_visibility (tree);
139 static int in_named_entry_eq (const void *, const void *);
140 static hashval_t in_named_entry_hash (const void *);
141 #ifdef ASM_OUTPUT_BSS
142 static void asm_output_bss (FILE *, tree, const char *,
143 unsigned HOST_WIDE_INT, unsigned HOST_WIDE_INT);
144 #endif
145 #ifdef BSS_SECTION_ASM_OP
146 #ifdef ASM_OUTPUT_ALIGNED_BSS
147 static void asm_output_aligned_bss (FILE *, tree, const char *,
148 unsigned HOST_WIDE_INT, int)
149 ATTRIBUTE_UNUSED;
150 #endif
151 #endif /* BSS_SECTION_ASM_OP */
152 static bool asm_emit_uninitialised (tree, const char*,
153 unsigned HOST_WIDE_INT,
154 unsigned HOST_WIDE_INT);
155 static void mark_weak (tree);
156 \f
157 enum in_section { no_section, in_text, in_unlikely_executed_text, in_data,
158 in_named
159 #ifdef BSS_SECTION_ASM_OP
160 , in_bss
161 #endif
162 #ifdef CTORS_SECTION_ASM_OP
163 , in_ctors
164 #endif
165 #ifdef DTORS_SECTION_ASM_OP
166 , in_dtors
167 #endif
168 #ifdef READONLY_DATA_SECTION_ASM_OP
169 , in_readonly_data
170 #endif
171 #ifdef EXTRA_SECTIONS
172 , EXTRA_SECTIONS
173 #endif
174 };
175 static GTY(()) enum in_section in_section = no_section;
176
177 /* Return a nonzero value if DECL has a section attribute. */
178 #ifndef IN_NAMED_SECTION
179 #define IN_NAMED_SECTION(DECL) \
180 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \
181 && DECL_SECTION_NAME (DECL) != NULL_TREE)
182 #endif
183
184 /* Text of section name when in_section == in_named. */
185 static GTY(()) const char *in_named_name;
186
187 /* Hash table of flags that have been used for a particular named section. */
188
189 struct in_named_entry GTY(())
190 {
191 const char *name;
192 unsigned int flags;
193 bool declared;
194 };
195
196 static GTY((param_is (struct in_named_entry))) htab_t in_named_htab;
197
198 /* Define functions like text_section for any extra sections. */
199 #ifdef EXTRA_SECTION_FUNCTIONS
200 EXTRA_SECTION_FUNCTIONS
201 #endif
202
203 /* Tell assembler to switch to text section. */
204
205 void
206 text_section (void)
207 {
208 if (in_section != in_text)
209 {
210 in_section = in_text;
211 fprintf (asm_out_file, "%s\n", TEXT_SECTION_ASM_OP);
212 ASM_OUTPUT_ALIGN (asm_out_file, 2);
213 }
214 }
215
216 /* Tell assembler to switch to unlikely-to-be-executed text section. */
217
218 void
219 unlikely_text_section (void)
220 {
221 if ((in_section != in_unlikely_executed_text)
222 && (in_section != in_named
223 || strcmp (in_named_name, UNLIKELY_EXECUTED_TEXT_SECTION_NAME) != 0))
224 {
225 if (targetm.have_named_sections)
226 named_section (NULL_TREE, UNLIKELY_EXECUTED_TEXT_SECTION_NAME, 0);
227 else
228 {
229 in_section = in_unlikely_executed_text;
230 fprintf (asm_out_file, "%s\n", TEXT_SECTION_ASM_OP);
231 }
232
233 if (!unlikely_section_label_printed)
234 {
235 fprintf (asm_out_file, "__%s_unlikely_section:\n",
236 current_function_name ());
237 unlikely_section_label_printed = true;
238
239 /* Make sure that we have approprate alignment for instructions
240 in this section. */
241 assemble_align (FUNCTION_BOUNDARY);
242 }
243 }
244 }
245
246 /* Tell assembler to switch to data section. */
247
248 void
249 data_section (void)
250 {
251 if (in_section != in_data)
252 {
253 in_section = in_data;
254 fprintf (asm_out_file, "%s\n", DATA_SECTION_ASM_OP);
255 }
256 }
257
258 /* Tell assembler to switch to read-only data section. This is normally
259 the text section. */
260
261 void
262 readonly_data_section (void)
263 {
264 #ifdef READONLY_DATA_SECTION
265 READONLY_DATA_SECTION (); /* Note this can call data_section. */
266 #else
267 #ifdef READONLY_DATA_SECTION_ASM_OP
268 if (in_section != in_readonly_data)
269 {
270 in_section = in_readonly_data;
271 fputs (READONLY_DATA_SECTION_ASM_OP, asm_out_file);
272 fputc ('\n', asm_out_file);
273 }
274 #else
275 text_section ();
276 #endif
277 #endif
278 }
279
280 /* Determine if we're in the text section. */
281
282 int
283 in_text_section (void)
284 {
285 return in_section == in_text;
286 }
287
288 /* Determine if we're in the unlikely-to-be-executed text section. */
289
290 int
291 in_unlikely_text_section (void)
292 {
293 return in_section == in_unlikely_executed_text;
294 }
295
296 /* Determine if we're in the data section. */
297
298 int
299 in_data_section (void)
300 {
301 return in_section == in_data;
302 }
303
304 /* Helper routines for maintaining in_named_htab. */
305
306 static int
307 in_named_entry_eq (const void *p1, const void *p2)
308 {
309 const struct in_named_entry *old = p1;
310 const char *new = p2;
311
312 return strcmp (old->name, new) == 0;
313 }
314
315 static hashval_t
316 in_named_entry_hash (const void *p)
317 {
318 const struct in_named_entry *old = p;
319 return htab_hash_string (old->name);
320 }
321
322 /* If SECTION has been seen before as a named section, return the flags
323 that were used. Otherwise, return 0. Note, that 0 is a perfectly valid
324 set of flags for a section to have, so 0 does not mean that the section
325 has not been seen. */
326
327 unsigned int
328 get_named_section_flags (const char *section)
329 {
330 struct in_named_entry **slot;
331
332 slot = (struct in_named_entry **)
333 htab_find_slot_with_hash (in_named_htab, section,
334 htab_hash_string (section), NO_INSERT);
335
336 return slot ? (*slot)->flags : 0;
337 }
338
339 /* Returns true if the section has been declared before. Sets internal
340 flag on this section in in_named_hash so subsequent calls on this
341 section will return false. */
342
343 bool
344 named_section_first_declaration (const char *name)
345 {
346 struct in_named_entry **slot;
347
348 slot = (struct in_named_entry **)
349 htab_find_slot_with_hash (in_named_htab, name,
350 htab_hash_string (name), NO_INSERT);
351 if (! (*slot)->declared)
352 {
353 (*slot)->declared = true;
354 return true;
355 }
356 else
357 {
358 return false;
359 }
360 }
361
362
363 /* Record FLAGS for SECTION. If SECTION was previously recorded with a
364 different set of flags, return false. */
365
366 bool
367 set_named_section_flags (const char *section, unsigned int flags)
368 {
369 struct in_named_entry **slot, *entry;
370
371 slot = (struct in_named_entry **)
372 htab_find_slot_with_hash (in_named_htab, section,
373 htab_hash_string (section), INSERT);
374 entry = *slot;
375
376 if (!entry)
377 {
378 entry = ggc_alloc (sizeof (*entry));
379 *slot = entry;
380 entry->name = ggc_strdup (section);
381 entry->flags = flags;
382 entry->declared = false;
383 }
384 else if (entry->flags != flags)
385 return false;
386
387 return true;
388 }
389
390 /* Tell assembler to change to section NAME with attributes FLAGS. */
391
392 void
393 named_section_flags (const char *name, unsigned int flags)
394 {
395 if (in_section != in_named || strcmp (name, in_named_name) != 0)
396 {
397 if (! set_named_section_flags (name, flags))
398 abort ();
399
400 targetm.asm_out.named_section (name, flags);
401
402 if (flags & SECTION_FORGET)
403 in_section = no_section;
404 else
405 {
406 in_named_name = ggc_strdup (name);
407 in_section = in_named;
408 }
409 }
410 }
411
412 /* Tell assembler to change to section NAME for DECL.
413 If DECL is NULL, just switch to section NAME.
414 If NAME is NULL, get the name from DECL.
415 If RELOC is 1, the initializer for DECL contains relocs. */
416
417 void
418 named_section (tree decl, const char *name, int reloc)
419 {
420 unsigned int flags;
421
422 if (decl != NULL_TREE && !DECL_P (decl))
423 abort ();
424 if (name == NULL)
425 name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
426
427 flags = targetm.section_type_flags (decl, name, reloc);
428
429 /* Sanity check user variables for flag changes. Non-user
430 section flag changes will abort in named_section_flags.
431 However, don't complain if SECTION_OVERRIDE is set.
432 We trust that the setter knows that it is safe to ignore
433 the default flags for this decl. */
434 if (decl && ! set_named_section_flags (name, flags))
435 {
436 flags = get_named_section_flags (name);
437 if ((flags & SECTION_OVERRIDE) == 0)
438 error ("%J%D causes a section type conflict", decl, decl);
439 }
440
441 named_section_flags (name, flags);
442 }
443
444 /* If required, set DECL_SECTION_NAME to a unique name. */
445
446 void
447 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
448 int flag_function_or_data_sections)
449 {
450 if (DECL_SECTION_NAME (decl) == NULL_TREE
451 && targetm.have_named_sections
452 && (flag_function_or_data_sections
453 || DECL_ONE_ONLY (decl)))
454 targetm.asm_out.unique_section (decl, reloc);
455 }
456
457 #ifdef BSS_SECTION_ASM_OP
458
459 /* Tell the assembler to switch to the bss section. */
460
461 void
462 bss_section (void)
463 {
464 if (in_section != in_bss)
465 {
466 fprintf (asm_out_file, "%s\n", BSS_SECTION_ASM_OP);
467 in_section = in_bss;
468 }
469 }
470
471 #ifdef ASM_OUTPUT_BSS
472
473 /* Utility function for ASM_OUTPUT_BSS for targets to use if
474 they don't support alignments in .bss.
475 ??? It is believed that this function will work in most cases so such
476 support is localized here. */
477
478 static void
479 asm_output_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
480 const char *name,
481 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
482 unsigned HOST_WIDE_INT rounded)
483 {
484 targetm.asm_out.globalize_label (file, name);
485 bss_section ();
486 #ifdef ASM_DECLARE_OBJECT_NAME
487 last_assemble_variable_decl = decl;
488 ASM_DECLARE_OBJECT_NAME (file, name, decl);
489 #else
490 /* Standard thing is just output label for the object. */
491 ASM_OUTPUT_LABEL (file, name);
492 #endif /* ASM_DECLARE_OBJECT_NAME */
493 ASM_OUTPUT_SKIP (file, rounded ? rounded : 1);
494 }
495
496 #endif
497
498 #ifdef ASM_OUTPUT_ALIGNED_BSS
499
500 /* Utility function for targets to use in implementing
501 ASM_OUTPUT_ALIGNED_BSS.
502 ??? It is believed that this function will work in most cases so such
503 support is localized here. */
504
505 static void
506 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
507 const char *name, unsigned HOST_WIDE_INT size,
508 int align)
509 {
510 bss_section ();
511 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
512 #ifdef ASM_DECLARE_OBJECT_NAME
513 last_assemble_variable_decl = decl;
514 ASM_DECLARE_OBJECT_NAME (file, name, decl);
515 #else
516 /* Standard thing is just output label for the object. */
517 ASM_OUTPUT_LABEL (file, name);
518 #endif /* ASM_DECLARE_OBJECT_NAME */
519 ASM_OUTPUT_SKIP (file, size ? size : 1);
520 }
521
522 #endif
523
524 #endif /* BSS_SECTION_ASM_OP */
525
526 /* Switch to the section for function DECL.
527
528 If DECL is NULL_TREE, switch to the text section.
529 ??? It's not clear that we will ever be passed NULL_TREE, but it's
530 safer to handle it. */
531
532 void
533 function_section (tree decl)
534 {
535 if (scan_ahead_for_unlikely_executed_note (get_insns()))
536 unlikely_text_section ();
537 else
538 {
539 if (decl != NULL_TREE
540 && DECL_SECTION_NAME (decl) != NULL_TREE)
541 named_section (decl, (char *) 0, 0);
542 else
543 text_section ();
544 }
545 }
546
547 /* Switch to section for variable DECL. RELOC is the same as the
548 argument to SELECT_SECTION. */
549
550 void
551 variable_section (tree decl, int reloc)
552 {
553 if (IN_NAMED_SECTION (decl))
554 named_section (decl, NULL, reloc);
555 else
556 targetm.asm_out.select_section (decl, reloc, DECL_ALIGN (decl));
557 }
558
559 /* Tell assembler to switch to the section for string merging. */
560
561 void
562 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
563 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
564 unsigned int flags ATTRIBUTE_UNUSED)
565 {
566 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
567 && TREE_CODE (decl) == STRING_CST
568 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
569 && align <= 256
570 && TREE_STRING_LENGTH (decl) >= int_size_in_bytes (TREE_TYPE (decl)))
571 {
572 enum machine_mode mode;
573 unsigned int modesize;
574 const char *str;
575 int i, j, len, unit;
576 char name[30];
577
578 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
579 modesize = GET_MODE_BITSIZE (mode);
580 if (modesize >= 8 && modesize <= 256
581 && (modesize & (modesize - 1)) == 0)
582 {
583 if (align < modesize)
584 align = modesize;
585
586 str = TREE_STRING_POINTER (decl);
587 len = TREE_STRING_LENGTH (decl);
588 unit = GET_MODE_SIZE (mode);
589
590 /* Check for embedded NUL characters. */
591 for (i = 0; i < len; i += unit)
592 {
593 for (j = 0; j < unit; j++)
594 if (str[i + j] != '\0')
595 break;
596 if (j == unit)
597 break;
598 }
599 if (i == len - unit)
600 {
601 sprintf (name, ".rodata.str%d.%d", modesize / 8,
602 (int) (align / 8));
603 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
604 if (!i && modesize < align)
605 {
606 /* A "" string with requested alignment greater than
607 character size might cause a problem:
608 if some other string required even bigger
609 alignment than "", then linker might think the
610 "" is just part of padding after some other string
611 and not put it into the hash table initially.
612 But this means "" could have smaller alignment
613 than requested. */
614 #ifdef ASM_OUTPUT_SECTION_START
615 named_section_flags (name, flags);
616 ASM_OUTPUT_SECTION_START (asm_out_file);
617 #else
618 readonly_data_section ();
619 #endif
620 return;
621 }
622
623 named_section_flags (name, flags);
624 return;
625 }
626 }
627 }
628
629 readonly_data_section ();
630 }
631
632 /* Tell assembler to switch to the section for constant merging. */
633
634 void
635 mergeable_constant_section (enum machine_mode mode ATTRIBUTE_UNUSED,
636 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
637 unsigned int flags ATTRIBUTE_UNUSED)
638 {
639 unsigned int modesize = GET_MODE_BITSIZE (mode);
640
641 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
642 && mode != VOIDmode
643 && mode != BLKmode
644 && modesize <= align
645 && align >= 8
646 && align <= 256
647 && (align & (align - 1)) == 0)
648 {
649 char name[24];
650
651 sprintf (name, ".rodata.cst%d", (int) (align / 8));
652 flags |= (align / 8) | SECTION_MERGE;
653 named_section_flags (name, flags);
654 return;
655 }
656
657 readonly_data_section ();
658 }
659 \f
660 /* Given NAME, a putative register name, discard any customary prefixes. */
661
662 static const char *
663 strip_reg_name (const char *name)
664 {
665 #ifdef REGISTER_PREFIX
666 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
667 name += strlen (REGISTER_PREFIX);
668 #endif
669 if (name[0] == '%' || name[0] == '#')
670 name++;
671 return name;
672 }
673 \f
674 /* Decode an `asm' spec for a declaration as a register name.
675 Return the register number, or -1 if nothing specified,
676 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
677 or -3 if ASMSPEC is `cc' and is not recognized,
678 or -4 if ASMSPEC is `memory' and is not recognized.
679 Accept an exact spelling or a decimal number.
680 Prefixes such as % are optional. */
681
682 int
683 decode_reg_name (const char *asmspec)
684 {
685 if (asmspec != 0)
686 {
687 int i;
688
689 /* Get rid of confusing prefixes. */
690 asmspec = strip_reg_name (asmspec);
691
692 /* Allow a decimal number as a "register name". */
693 for (i = strlen (asmspec) - 1; i >= 0; i--)
694 if (! ISDIGIT (asmspec[i]))
695 break;
696 if (asmspec[0] != 0 && i < 0)
697 {
698 i = atoi (asmspec);
699 if (i < FIRST_PSEUDO_REGISTER && i >= 0)
700 return i;
701 else
702 return -2;
703 }
704
705 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
706 if (reg_names[i][0]
707 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
708 return i;
709
710 #ifdef ADDITIONAL_REGISTER_NAMES
711 {
712 static const struct { const char *const name; const int number; } table[]
713 = ADDITIONAL_REGISTER_NAMES;
714
715 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
716 if (! strcmp (asmspec, table[i].name))
717 return table[i].number;
718 }
719 #endif /* ADDITIONAL_REGISTER_NAMES */
720
721 if (!strcmp (asmspec, "memory"))
722 return -4;
723
724 if (!strcmp (asmspec, "cc"))
725 return -3;
726
727 return -2;
728 }
729
730 return -1;
731 }
732 \f
733 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
734 have static storage duration. In other words, it should not be an
735 automatic variable, including PARM_DECLs.
736
737 There is, however, one exception: this function handles variables
738 explicitly placed in a particular register by the user.
739
740 ASMSPEC, if not 0, is the string which the user specified as the
741 assembler symbol name.
742
743 This is never called for PARM_DECL nodes. */
744
745 void
746 make_decl_rtl (tree decl, const char *asmspec)
747 {
748 const char *name = 0;
749 int reg_number;
750 rtx x;
751
752 /* Check that we are not being given an automatic variable. */
753 /* A weak alias has TREE_PUBLIC set but not the other bits. */
754 if (TREE_CODE (decl) == PARM_DECL
755 || TREE_CODE (decl) == RESULT_DECL
756 || (TREE_CODE (decl) == VAR_DECL
757 && !TREE_STATIC (decl)
758 && !TREE_PUBLIC (decl)
759 && !DECL_EXTERNAL (decl)
760 && !DECL_REGISTER (decl)))
761 abort ();
762 /* And that we were not given a type or a label. */
763 else if (TREE_CODE (decl) == TYPE_DECL
764 || TREE_CODE (decl) == LABEL_DECL)
765 abort ();
766
767 /* For a duplicate declaration, we can be called twice on the
768 same DECL node. Don't discard the RTL already made. */
769 if (DECL_RTL_SET_P (decl))
770 {
771 /* If the old RTL had the wrong mode, fix the mode. */
772 if (GET_MODE (DECL_RTL (decl)) != DECL_MODE (decl))
773 SET_DECL_RTL (decl, adjust_address_nv (DECL_RTL (decl),
774 DECL_MODE (decl), 0));
775
776 /* ??? Another way to do this would be to maintain a hashed
777 table of such critters. Instead of adding stuff to a DECL
778 to give certain attributes to it, we could use an external
779 hash map from DECL to set of attributes. */
780
781 /* Let the target reassign the RTL if it wants.
782 This is necessary, for example, when one machine specific
783 decl attribute overrides another. */
784 targetm.encode_section_info (decl, DECL_RTL (decl), false);
785 return;
786 }
787
788 reg_number = decode_reg_name (asmspec);
789 if (reg_number == -2)
790 {
791 /* ASMSPEC is given, and not the name of a register. Mark the
792 name with a star so assemble_name won't munge it. */
793 char *starred = alloca (strlen (asmspec) + 2);
794 starred[0] = '*';
795 strcpy (starred + 1, asmspec);
796 change_decl_assembler_name (decl, get_identifier (starred));
797 }
798
799 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
800
801 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
802 {
803 /* First detect errors in declaring global registers. */
804 if (reg_number == -1)
805 error ("%Jregister name not specified for '%D'", decl, decl);
806 else if (reg_number < 0)
807 error ("%Jinvalid register name for '%D'", decl, decl);
808 else if (TYPE_MODE (TREE_TYPE (decl)) == BLKmode)
809 error ("%Jdata type of '%D' isn't suitable for a register",
810 decl, decl);
811 else if (! HARD_REGNO_MODE_OK (reg_number, TYPE_MODE (TREE_TYPE (decl))))
812 error ("%Jregister specified for '%D' isn't suitable for data type",
813 decl, decl);
814 /* Now handle properly declared static register variables. */
815 else
816 {
817 int nregs;
818
819 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
820 {
821 DECL_INITIAL (decl) = 0;
822 error ("global register variable has initial value");
823 }
824 if (TREE_THIS_VOLATILE (decl))
825 warning ("volatile register variables don't work as you might wish");
826
827 /* If the user specified one of the eliminables registers here,
828 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
829 confused with that register and be eliminated. This usage is
830 somewhat suspect... */
831
832 SET_DECL_RTL (decl, gen_rtx_raw_REG (DECL_MODE (decl), reg_number));
833 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
834 REG_USERVAR_P (DECL_RTL (decl)) = 1;
835
836 if (TREE_STATIC (decl))
837 {
838 /* Make this register global, so not usable for anything
839 else. */
840 #ifdef ASM_DECLARE_REGISTER_GLOBAL
841 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
842 #endif
843 nregs = hard_regno_nregs[reg_number][DECL_MODE (decl)];
844 while (nregs > 0)
845 globalize_reg (reg_number + --nregs);
846 }
847
848 /* As a register variable, it has no section. */
849 return;
850 }
851 }
852
853 /* Now handle ordinary static variables and functions (in memory).
854 Also handle vars declared register invalidly. */
855
856 if (reg_number >= 0 || reg_number == -3)
857 error ("%Jregister name given for non-register variable '%D'", decl, decl);
858
859 /* Specifying a section attribute on a variable forces it into a
860 non-.bss section, and thus it cannot be common. */
861 if (TREE_CODE (decl) == VAR_DECL
862 && DECL_SECTION_NAME (decl) != NULL_TREE
863 && DECL_INITIAL (decl) == NULL_TREE
864 && DECL_COMMON (decl))
865 DECL_COMMON (decl) = 0;
866
867 /* Variables can't be both common and weak. */
868 if (TREE_CODE (decl) == VAR_DECL && DECL_WEAK (decl))
869 DECL_COMMON (decl) = 0;
870
871 x = gen_rtx_SYMBOL_REF (Pmode, name);
872 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
873 SYMBOL_REF_DECL (x) = decl;
874
875 x = gen_rtx_MEM (DECL_MODE (decl), x);
876 if (TREE_CODE (decl) != FUNCTION_DECL)
877 set_mem_attributes (x, decl, 1);
878 SET_DECL_RTL (decl, x);
879
880 /* Optionally set flags or add text to the name to record information
881 such as that it is a function name.
882 If the name is changed, the macro ASM_OUTPUT_LABELREF
883 will have to know how to strip this information. */
884 targetm.encode_section_info (decl, DECL_RTL (decl), true);
885 }
886
887 /* Make the rtl for variable VAR be volatile.
888 Use this only for static variables. */
889
890 void
891 make_var_volatile (tree var)
892 {
893 if (GET_CODE (DECL_RTL (var)) != MEM)
894 abort ();
895
896 MEM_VOLATILE_P (DECL_RTL (var)) = 1;
897 }
898 \f
899 /* Output a string of literal assembler code
900 for an `asm' keyword used between functions. */
901
902 void
903 assemble_asm (tree string)
904 {
905 app_enable ();
906
907 if (TREE_CODE (string) == ADDR_EXPR)
908 string = TREE_OPERAND (string, 0);
909
910 fprintf (asm_out_file, "\t%s\n", TREE_STRING_POINTER (string));
911 }
912
913 /* Record an element in the table of global destructors. SYMBOL is
914 a SYMBOL_REF of the function to be called; PRIORITY is a number
915 between 0 and MAX_INIT_PRIORITY. */
916
917 void
918 default_stabs_asm_out_destructor (rtx symbol, int priority ATTRIBUTE_UNUSED)
919 {
920 /* Tell GNU LD that this is part of the static destructor set.
921 This will work for any system that uses stabs, most usefully
922 aout systems. */
923 fprintf (asm_out_file, "%s\"___DTOR_LIST__\",22,0,0,", ASM_STABS_OP);
924 assemble_name (asm_out_file, XSTR (symbol, 0));
925 fputc ('\n', asm_out_file);
926 }
927
928 void
929 default_named_section_asm_out_destructor (rtx symbol, int priority)
930 {
931 const char *section = ".dtors";
932 char buf[16];
933
934 /* ??? This only works reliably with the GNU linker. */
935 if (priority != DEFAULT_INIT_PRIORITY)
936 {
937 sprintf (buf, ".dtors.%.5u",
938 /* Invert the numbering so the linker puts us in the proper
939 order; constructors are run from right to left, and the
940 linker sorts in increasing order. */
941 MAX_INIT_PRIORITY - priority);
942 section = buf;
943 }
944
945 named_section_flags (section, SECTION_WRITE);
946 assemble_align (POINTER_SIZE);
947 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
948 }
949
950 #ifdef DTORS_SECTION_ASM_OP
951 void
952 dtors_section (void)
953 {
954 if (in_section != in_dtors)
955 {
956 in_section = in_dtors;
957 fputs (DTORS_SECTION_ASM_OP, asm_out_file);
958 fputc ('\n', asm_out_file);
959 }
960 }
961
962 void
963 default_dtor_section_asm_out_destructor (rtx symbol,
964 int priority ATTRIBUTE_UNUSED)
965 {
966 dtors_section ();
967 assemble_align (POINTER_SIZE);
968 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
969 }
970 #endif
971
972 /* Likewise for global constructors. */
973
974 void
975 default_stabs_asm_out_constructor (rtx symbol, int priority ATTRIBUTE_UNUSED)
976 {
977 /* Tell GNU LD that this is part of the static destructor set.
978 This will work for any system that uses stabs, most usefully
979 aout systems. */
980 fprintf (asm_out_file, "%s\"___CTOR_LIST__\",22,0,0,", ASM_STABS_OP);
981 assemble_name (asm_out_file, XSTR (symbol, 0));
982 fputc ('\n', asm_out_file);
983 }
984
985 void
986 default_named_section_asm_out_constructor (rtx symbol, int priority)
987 {
988 const char *section = ".ctors";
989 char buf[16];
990
991 /* ??? This only works reliably with the GNU linker. */
992 if (priority != DEFAULT_INIT_PRIORITY)
993 {
994 sprintf (buf, ".ctors.%.5u",
995 /* Invert the numbering so the linker puts us in the proper
996 order; constructors are run from right to left, and the
997 linker sorts in increasing order. */
998 MAX_INIT_PRIORITY - priority);
999 section = buf;
1000 }
1001
1002 named_section_flags (section, SECTION_WRITE);
1003 assemble_align (POINTER_SIZE);
1004 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1005 }
1006
1007 #ifdef CTORS_SECTION_ASM_OP
1008 void
1009 ctors_section (void)
1010 {
1011 if (in_section != in_ctors)
1012 {
1013 in_section = in_ctors;
1014 fputs (CTORS_SECTION_ASM_OP, asm_out_file);
1015 fputc ('\n', asm_out_file);
1016 }
1017 }
1018
1019 void
1020 default_ctor_section_asm_out_constructor (rtx symbol,
1021 int priority ATTRIBUTE_UNUSED)
1022 {
1023 ctors_section ();
1024 assemble_align (POINTER_SIZE);
1025 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1026 }
1027 #endif
1028 \f
1029 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1030 a nonzero value if the constant pool should be output before the
1031 start of the function, or a zero value if the pool should output
1032 after the end of the function. The default is to put it before the
1033 start. */
1034
1035 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1036 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1037 #endif
1038
1039 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1040 to be output to assembler.
1041 Set first_global_object_name and weak_global_object_name as appropriate. */
1042
1043 void
1044 notice_global_symbol (tree decl)
1045 {
1046 const char **type = &first_global_object_name;
1047
1048 if (first_global_object_name
1049 || !TREE_PUBLIC (decl) || DECL_EXTERNAL (decl)
1050 || !DECL_NAME (decl)
1051 || (TREE_CODE (decl) != FUNCTION_DECL
1052 && (TREE_CODE (decl) != VAR_DECL
1053 || (DECL_COMMON (decl)
1054 && (DECL_INITIAL (decl) == 0
1055 || DECL_INITIAL (decl) == error_mark_node))))
1056 || GET_CODE (DECL_RTL (decl)) != MEM)
1057 return;
1058
1059 /* We win when global object is found, but it is useful to know about weak
1060 symbol as well so we can produce nicer unique names. */
1061 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl))
1062 type = &weak_global_object_name;
1063
1064 if (!*type)
1065 {
1066 const char *p;
1067 char *name;
1068 rtx decl_rtl = DECL_RTL (decl);
1069
1070 p = targetm.strip_name_encoding (XSTR (XEXP (decl_rtl, 0), 0));
1071 name = xstrdup (p);
1072
1073 *type = name;
1074 }
1075 }
1076
1077 /* Output assembler code for the constant pool of a function and associated
1078 with defining the name of the function. DECL describes the function.
1079 NAME is the function's name. For the constant pool, we use the current
1080 constant pool data. */
1081
1082 void
1083 assemble_start_function (tree decl, const char *fnname)
1084 {
1085 int align;
1086
1087 unlikely_section_label_printed = false;
1088
1089 /* The following code does not need preprocessing in the assembler. */
1090
1091 app_disable ();
1092
1093 if (CONSTANT_POOL_BEFORE_FUNCTION)
1094 output_constant_pool (fnname, decl);
1095
1096 resolve_unique_section (decl, 0, flag_function_sections);
1097 function_section (decl);
1098
1099 /* Tell assembler to move to target machine's alignment for functions. */
1100 align = floor_log2 (FUNCTION_BOUNDARY / BITS_PER_UNIT);
1101 if (align < force_align_functions_log)
1102 align = force_align_functions_log;
1103 if (align > 0)
1104 {
1105 ASM_OUTPUT_ALIGN (asm_out_file, align);
1106 }
1107
1108 /* Handle a user-specified function alignment.
1109 Note that we still need to align to FUNCTION_BOUNDARY, as above,
1110 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1111 if (align_functions_log > align
1112 && cfun->function_frequency != FUNCTION_FREQUENCY_UNLIKELY_EXECUTED)
1113 {
1114 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1115 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1116 align_functions_log, align_functions - 1);
1117 #else
1118 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1119 #endif
1120 }
1121
1122 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1123 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1124 #endif
1125
1126 (*debug_hooks->begin_function) (decl);
1127
1128 /* Make function name accessible from other files, if appropriate. */
1129
1130 if (TREE_PUBLIC (decl))
1131 {
1132 notice_global_symbol (decl);
1133
1134 globalize_decl (decl);
1135
1136 maybe_assemble_visibility (decl);
1137 }
1138
1139 /* Do any machine/system dependent processing of the function name. */
1140 #ifdef ASM_DECLARE_FUNCTION_NAME
1141 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1142 #else
1143 /* Standard thing is just output label for the function. */
1144 ASM_OUTPUT_LABEL (asm_out_file, fnname);
1145 #endif /* ASM_DECLARE_FUNCTION_NAME */
1146 }
1147
1148 /* Output assembler code associated with defining the size of the
1149 function. DECL describes the function. NAME is the function's name. */
1150
1151 void
1152 assemble_end_function (tree decl, const char *fnname)
1153 {
1154 #ifdef ASM_DECLARE_FUNCTION_SIZE
1155 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1156 #endif
1157 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1158 {
1159 output_constant_pool (fnname, decl);
1160 function_section (decl); /* need to switch back */
1161 }
1162 }
1163 \f
1164 /* Assemble code to leave SIZE bytes of zeros. */
1165
1166 void
1167 assemble_zeros (unsigned HOST_WIDE_INT size)
1168 {
1169 /* Do no output if -fsyntax-only. */
1170 if (flag_syntax_only)
1171 return;
1172
1173 #ifdef ASM_NO_SKIP_IN_TEXT
1174 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1175 so we must output 0s explicitly in the text section. */
1176 if ((ASM_NO_SKIP_IN_TEXT && in_text_section ())
1177 || (ASM_NO_SKIP_IN_TEXT && in_unlikely_text_section ()))
1178 {
1179 unsigned HOST_WIDE_INT i;
1180 for (i = 0; i < size; i++)
1181 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1182 }
1183 else
1184 #endif
1185 if (size > 0)
1186 ASM_OUTPUT_SKIP (asm_out_file, size);
1187 }
1188
1189 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1190
1191 void
1192 assemble_align (int align)
1193 {
1194 if (align > BITS_PER_UNIT)
1195 {
1196 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1197 }
1198 }
1199
1200 /* Assemble a string constant with the specified C string as contents. */
1201
1202 void
1203 assemble_string (const char *p, int size)
1204 {
1205 int pos = 0;
1206 int maximum = 2000;
1207
1208 /* If the string is very long, split it up. */
1209
1210 while (pos < size)
1211 {
1212 int thissize = size - pos;
1213 if (thissize > maximum)
1214 thissize = maximum;
1215
1216 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1217
1218 pos += thissize;
1219 p += thissize;
1220 }
1221 }
1222
1223 \f
1224 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1225 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1226 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1227 #else
1228 #if defined ASM_OUTPUT_ALIGNED_LOCAL
1229 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1230 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, DECL_ALIGN (decl))
1231 #else
1232 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1233 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded)
1234 #endif
1235 #endif
1236
1237 #if defined ASM_OUTPUT_ALIGNED_BSS
1238 #define ASM_EMIT_BSS(decl, name, size, rounded) \
1239 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1240 #else
1241 #if defined ASM_OUTPUT_BSS
1242 #define ASM_EMIT_BSS(decl, name, size, rounded) \
1243 ASM_OUTPUT_BSS (asm_out_file, decl, name, size, rounded)
1244 #else
1245 #undef ASM_EMIT_BSS
1246 #endif
1247 #endif
1248
1249 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1250 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1251 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1252 #else
1253 #if defined ASM_OUTPUT_ALIGNED_COMMON
1254 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1255 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size, DECL_ALIGN (decl))
1256 #else
1257 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1258 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded)
1259 #endif
1260 #endif
1261
1262 static bool
1263 asm_emit_uninitialised (tree decl, const char *name,
1264 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1265 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1266 {
1267 enum
1268 {
1269 asm_dest_common,
1270 asm_dest_bss,
1271 asm_dest_local
1272 }
1273 destination = asm_dest_local;
1274
1275 /* ??? We should handle .bss via select_section mechanisms rather than
1276 via special target hooks. That would eliminate this special case. */
1277 if (TREE_PUBLIC (decl))
1278 {
1279 if (!DECL_COMMON (decl))
1280 #ifdef ASM_EMIT_BSS
1281 destination = asm_dest_bss;
1282 #else
1283 return false;
1284 #endif
1285 else
1286 destination = asm_dest_common;
1287 }
1288
1289 if (destination == asm_dest_bss)
1290 globalize_decl (decl);
1291 resolve_unique_section (decl, 0, flag_data_sections);
1292
1293 if (flag_shared_data)
1294 {
1295 switch (destination)
1296 {
1297 #ifdef ASM_OUTPUT_SHARED_BSS
1298 case asm_dest_bss:
1299 ASM_OUTPUT_SHARED_BSS (asm_out_file, decl, name, size, rounded);
1300 return;
1301 #endif
1302 #ifdef ASM_OUTPUT_SHARED_COMMON
1303 case asm_dest_common:
1304 ASM_OUTPUT_SHARED_COMMON (asm_out_file, name, size, rounded);
1305 return;
1306 #endif
1307 #ifdef ASM_OUTPUT_SHARED_LOCAL
1308 case asm_dest_local:
1309 ASM_OUTPUT_SHARED_LOCAL (asm_out_file, name, size, rounded);
1310 return;
1311 #endif
1312 default:
1313 break;
1314 }
1315 }
1316
1317 switch (destination)
1318 {
1319 #ifdef ASM_EMIT_BSS
1320 case asm_dest_bss:
1321 ASM_EMIT_BSS (decl, name, size, rounded);
1322 break;
1323 #endif
1324 case asm_dest_common:
1325 ASM_EMIT_COMMON (decl, name, size, rounded);
1326 break;
1327 case asm_dest_local:
1328 ASM_EMIT_LOCAL (decl, name, size, rounded);
1329 break;
1330 default:
1331 abort ();
1332 }
1333
1334 return true;
1335 }
1336
1337 /* Assemble everything that is needed for a variable or function declaration.
1338 Not used for automatic variables, and not used for function definitions.
1339 Should not be called for variables of incomplete structure type.
1340
1341 TOP_LEVEL is nonzero if this variable has file scope.
1342 AT_END is nonzero if this is the special handling, at end of compilation,
1343 to define things that have had only tentative definitions.
1344 DONT_OUTPUT_DATA if nonzero means don't actually output the
1345 initial value (that will be done by the caller). */
1346
1347 void
1348 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
1349 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
1350 {
1351 const char *name;
1352 unsigned int align;
1353 int reloc = 0;
1354 rtx decl_rtl;
1355
1356 if (lang_hooks.decls.prepare_assemble_variable)
1357 lang_hooks.decls.prepare_assemble_variable (decl);
1358
1359 last_assemble_variable_decl = 0;
1360
1361 /* Normally no need to say anything here for external references,
1362 since assemble_external is called by the language-specific code
1363 when a declaration is first seen. */
1364
1365 if (DECL_EXTERNAL (decl))
1366 return;
1367
1368 /* Output no assembler code for a function declaration.
1369 Only definitions of functions output anything. */
1370
1371 if (TREE_CODE (decl) == FUNCTION_DECL)
1372 return;
1373
1374 /* Do nothing for global register variables. */
1375 if (DECL_RTL_SET_P (decl) && GET_CODE (DECL_RTL (decl)) == REG)
1376 {
1377 TREE_ASM_WRITTEN (decl) = 1;
1378 return;
1379 }
1380
1381 /* If type was incomplete when the variable was declared,
1382 see if it is complete now. */
1383
1384 if (DECL_SIZE (decl) == 0)
1385 layout_decl (decl, 0);
1386
1387 /* Still incomplete => don't allocate it; treat the tentative defn
1388 (which is what it must have been) as an `extern' reference. */
1389
1390 if (!dont_output_data && DECL_SIZE (decl) == 0)
1391 {
1392 error ("%Jstorage size of `%D' isn't known", decl, decl);
1393 TREE_ASM_WRITTEN (decl) = 1;
1394 return;
1395 }
1396
1397 /* The first declaration of a variable that comes through this function
1398 decides whether it is global (in C, has external linkage)
1399 or local (in C, has internal linkage). So do nothing more
1400 if this function has already run. */
1401
1402 if (TREE_ASM_WRITTEN (decl))
1403 return;
1404
1405 /* Make sure targetm.encode_section_info is invoked before we set
1406 ASM_WRITTEN. */
1407 decl_rtl = DECL_RTL (decl);
1408
1409 TREE_ASM_WRITTEN (decl) = 1;
1410
1411 /* Do no output if -fsyntax-only. */
1412 if (flag_syntax_only)
1413 return;
1414
1415 app_disable ();
1416
1417 if (! dont_output_data
1418 && ! host_integerp (DECL_SIZE_UNIT (decl), 1))
1419 {
1420 error ("%Jsize of variable '%D' is too large", decl, decl);
1421 return;
1422 }
1423
1424 name = XSTR (XEXP (decl_rtl, 0), 0);
1425 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
1426 notice_global_symbol (decl);
1427
1428 /* Compute the alignment of this data. */
1429
1430 align = DECL_ALIGN (decl);
1431
1432 /* In the case for initialing an array whose length isn't specified,
1433 where we have not yet been able to do the layout,
1434 figure out the proper alignment now. */
1435 if (dont_output_data && DECL_SIZE (decl) == 0
1436 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
1437 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
1438
1439 /* Some object file formats have a maximum alignment which they support.
1440 In particular, a.out format supports a maximum alignment of 4. */
1441 #ifndef MAX_OFILE_ALIGNMENT
1442 #define MAX_OFILE_ALIGNMENT BIGGEST_ALIGNMENT
1443 #endif
1444 if (align > MAX_OFILE_ALIGNMENT)
1445 {
1446 warning ("%Jalignment of '%D' is greater than maximum object "
1447 "file alignment. Using %d", decl, decl,
1448 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
1449 align = MAX_OFILE_ALIGNMENT;
1450 }
1451
1452 /* On some machines, it is good to increase alignment sometimes. */
1453 if (! DECL_USER_ALIGN (decl))
1454 {
1455 #ifdef DATA_ALIGNMENT
1456 align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1457 #endif
1458 #ifdef CONSTANT_ALIGNMENT
1459 if (DECL_INITIAL (decl) != 0 && DECL_INITIAL (decl) != error_mark_node)
1460 align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
1461 #endif
1462 }
1463
1464 /* Reset the alignment in case we have made it tighter, so we can benefit
1465 from it in get_pointer_alignment. */
1466 DECL_ALIGN (decl) = align;
1467 set_mem_align (decl_rtl, align);
1468
1469 if (TREE_PUBLIC (decl))
1470 maybe_assemble_visibility (decl);
1471
1472 /* Output any data that we will need to use the address of. */
1473 if (DECL_INITIAL (decl) == error_mark_node)
1474 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1475 else if (DECL_INITIAL (decl))
1476 {
1477 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1478 output_addressed_constants (DECL_INITIAL (decl));
1479 }
1480 resolve_unique_section (decl, reloc, flag_data_sections);
1481
1482 /* Handle uninitialized definitions. */
1483
1484 /* If the decl has been given an explicit section name, then it
1485 isn't common, and shouldn't be handled as such. */
1486 if (DECL_SECTION_NAME (decl) || dont_output_data)
1487 ;
1488 /* We don't implement common thread-local data at present. */
1489 else if (DECL_THREAD_LOCAL (decl))
1490 {
1491 if (DECL_COMMON (decl))
1492 sorry ("thread-local COMMON data not implemented");
1493 }
1494 else if (DECL_INITIAL (decl) == 0
1495 || DECL_INITIAL (decl) == error_mark_node
1496 || (flag_zero_initialized_in_bss
1497 /* Leave constant zeroes in .rodata so they can be shared. */
1498 && !TREE_READONLY (decl)
1499 && initializer_zerop (DECL_INITIAL (decl))))
1500 {
1501 unsigned HOST_WIDE_INT size = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
1502 unsigned HOST_WIDE_INT rounded = size;
1503
1504 /* Don't allocate zero bytes of common,
1505 since that means "undefined external" in the linker. */
1506 if (size == 0)
1507 rounded = 1;
1508
1509 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1510 so that each uninitialized object starts on such a boundary. */
1511 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
1512 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1513 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1514
1515 #if !defined(ASM_OUTPUT_ALIGNED_COMMON) && !defined(ASM_OUTPUT_ALIGNED_DECL_COMMON) && !defined(ASM_OUTPUT_ALIGNED_BSS)
1516 if ((unsigned HOST_WIDE_INT) DECL_ALIGN (decl) / BITS_PER_UNIT > rounded)
1517 warning ("%Jrequested alignment for '%D' is greater than "
1518 "implemented alignment of %d", decl, decl, rounded);
1519 #endif
1520
1521 /* If the target cannot output uninitialized but not common global data
1522 in .bss, then we have to use .data, so fall through. */
1523 if (asm_emit_uninitialised (decl, name, size, rounded))
1524 return;
1525 }
1526
1527 /* Handle initialized definitions.
1528 Also handle uninitialized global definitions if -fno-common and the
1529 target doesn't support ASM_OUTPUT_BSS. */
1530
1531 /* First make the assembler name(s) global if appropriate. */
1532 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
1533 globalize_decl (decl);
1534
1535 /* Switch to the appropriate section. */
1536 variable_section (decl, reloc);
1537
1538 /* dbxout.c needs to know this. */
1539 if (in_text_section () || in_unlikely_text_section ())
1540 DECL_IN_TEXT_SECTION (decl) = 1;
1541
1542 /* Output the alignment of this data. */
1543 if (align > BITS_PER_UNIT)
1544 {
1545 ASM_OUTPUT_ALIGN (asm_out_file,
1546 floor_log2 (DECL_ALIGN (decl) / BITS_PER_UNIT));
1547 }
1548
1549 /* Do any machine/system dependent processing of the object. */
1550 #ifdef ASM_DECLARE_OBJECT_NAME
1551 last_assemble_variable_decl = decl;
1552 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
1553 #else
1554 /* Standard thing is just output label for the object. */
1555 ASM_OUTPUT_LABEL (asm_out_file, name);
1556 #endif /* ASM_DECLARE_OBJECT_NAME */
1557
1558 if (!dont_output_data)
1559 {
1560 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
1561 /* Output the actual data. */
1562 output_constant (DECL_INITIAL (decl),
1563 tree_low_cst (DECL_SIZE_UNIT (decl), 1),
1564 align);
1565 else
1566 /* Leave space for it. */
1567 assemble_zeros (tree_low_cst (DECL_SIZE_UNIT (decl), 1));
1568 }
1569 }
1570
1571 /* Return 1 if type TYPE contains any pointers. */
1572
1573 static int
1574 contains_pointers_p (tree type)
1575 {
1576 switch (TREE_CODE (type))
1577 {
1578 case POINTER_TYPE:
1579 case REFERENCE_TYPE:
1580 /* I'm not sure whether OFFSET_TYPE needs this treatment,
1581 so I'll play safe and return 1. */
1582 case OFFSET_TYPE:
1583 return 1;
1584
1585 case RECORD_TYPE:
1586 case UNION_TYPE:
1587 case QUAL_UNION_TYPE:
1588 {
1589 tree fields;
1590 /* For a type that has fields, see if the fields have pointers. */
1591 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
1592 if (TREE_CODE (fields) == FIELD_DECL
1593 && contains_pointers_p (TREE_TYPE (fields)))
1594 return 1;
1595 return 0;
1596 }
1597
1598 case ARRAY_TYPE:
1599 /* An array type contains pointers if its element type does. */
1600 return contains_pointers_p (TREE_TYPE (type));
1601
1602 default:
1603 return 0;
1604 }
1605 }
1606
1607 #ifdef ASM_OUTPUT_EXTERNAL
1608 /* True if DECL is a function decl for which no out-of-line copy exists.
1609 It is assumed that DECL's assembler name has been set. */
1610
1611 static bool
1612 incorporeal_function_p (tree decl)
1613 {
1614 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
1615 {
1616 const char *name;
1617
1618 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
1619 && DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA)
1620 return true;
1621
1622 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
1623 if (strncmp (name, "__builtin_", strlen ("__builtin_")) == 0)
1624 return true;
1625 }
1626 return false;
1627 }
1628 #endif
1629
1630 /* Output something to declare an external symbol to the assembler.
1631 (Most assemblers don't need this, so we normally output nothing.)
1632 Do nothing if DECL is not external. */
1633
1634 void
1635 assemble_external (tree decl ATTRIBUTE_UNUSED)
1636 {
1637 /* Because most platforms do not define ASM_OUTPUT_EXTERNAL, the
1638 main body of this code is only rarely exercised. To provide some
1639 testing, on all platforms, we make sure that the ASM_OUT_FILE is
1640 open. If it's not, we should not be calling this function. */
1641 if (!asm_out_file)
1642 abort ();
1643
1644 #ifdef ASM_OUTPUT_EXTERNAL
1645 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
1646 {
1647 rtx rtl = DECL_RTL (decl);
1648
1649 if (GET_CODE (rtl) == MEM && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
1650 && !SYMBOL_REF_USED (XEXP (rtl, 0))
1651 && !incorporeal_function_p (decl))
1652 {
1653 /* Some systems do require some output. */
1654 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
1655 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
1656 }
1657 }
1658 #endif
1659 }
1660
1661 /* Similar, for calling a library function FUN. */
1662
1663 void
1664 assemble_external_libcall (rtx fun)
1665 {
1666 /* Declare library function name external when first used, if nec. */
1667 if (! SYMBOL_REF_USED (fun))
1668 {
1669 SYMBOL_REF_USED (fun) = 1;
1670 targetm.asm_out.external_libcall (fun);
1671 }
1672 }
1673
1674 /* Assemble a label named NAME. */
1675
1676 void
1677 assemble_label (const char *name)
1678 {
1679 ASM_OUTPUT_LABEL (asm_out_file, name);
1680 }
1681
1682 /* Set the symbol_referenced flag for ID and notify callgraph code. */
1683 void
1684 mark_referenced (tree id)
1685 {
1686 if (!TREE_SYMBOL_REFERENCED (id))
1687 {
1688 struct cgraph_node *node;
1689 struct cgraph_varpool_node *vnode;
1690
1691 if (!cgraph_global_info_ready)
1692 {
1693 node = cgraph_node_for_identifier (id);
1694 if (node)
1695 cgraph_mark_needed_node (node);
1696 }
1697
1698 vnode = cgraph_varpool_node_for_identifier (id);
1699 if (vnode)
1700 cgraph_varpool_mark_needed_node (vnode);
1701 }
1702 TREE_SYMBOL_REFERENCED (id) = 1;
1703 }
1704
1705 /* Output to FILE a reference to the assembler name of a C-level name NAME.
1706 If NAME starts with a *, the rest of NAME is output verbatim.
1707 Otherwise NAME is transformed in an implementation-defined way
1708 (usually by the addition of an underscore).
1709 Many macros in the tm file are defined to call this function. */
1710
1711 void
1712 assemble_name (FILE *file, const char *name)
1713 {
1714 const char *real_name;
1715 tree id;
1716
1717 real_name = targetm.strip_name_encoding (name);
1718
1719 id = maybe_get_identifier (real_name);
1720 if (id)
1721 mark_referenced (id);
1722
1723 if (name[0] == '*')
1724 fputs (&name[1], file);
1725 else
1726 ASM_OUTPUT_LABELREF (file, name);
1727 }
1728
1729 /* Allocate SIZE bytes writable static space with a gensym name
1730 and return an RTX to refer to its address. */
1731
1732 rtx
1733 assemble_static_space (unsigned HOST_WIDE_INT size)
1734 {
1735 char name[12];
1736 const char *namestring;
1737 rtx x;
1738
1739 #if 0
1740 if (flag_shared_data)
1741 data_section ();
1742 #endif
1743
1744 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
1745 ++const_labelno;
1746 namestring = ggc_strdup (name);
1747
1748 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
1749 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
1750
1751 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
1752 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
1753 BIGGEST_ALIGNMENT);
1754 #else
1755 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
1756 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
1757 #else
1758 {
1759 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1760 so that each uninitialized object starts on such a boundary. */
1761 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
1762 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
1763 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
1764 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1765 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1766 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1767 }
1768 #endif
1769 #endif
1770 return x;
1771 }
1772
1773 /* Assemble the static constant template for function entry trampolines.
1774 This is done at most once per compilation.
1775 Returns an RTX for the address of the template. */
1776
1777 #ifdef TRAMPOLINE_TEMPLATE
1778 rtx
1779 assemble_trampoline_template (void)
1780 {
1781 char label[256];
1782 const char *name;
1783 int align;
1784 rtx symbol;
1785
1786 /* By default, put trampoline templates in read-only data section. */
1787
1788 #ifdef TRAMPOLINE_SECTION
1789 TRAMPOLINE_SECTION ();
1790 #else
1791 readonly_data_section ();
1792 #endif
1793
1794 /* Write the assembler code to define one. */
1795 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
1796 if (align > 0)
1797 {
1798 ASM_OUTPUT_ALIGN (asm_out_file, align);
1799 }
1800
1801 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
1802 TRAMPOLINE_TEMPLATE (asm_out_file);
1803
1804 /* Record the rtl to refer to it. */
1805 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
1806 name = ggc_strdup (label);
1807 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
1808 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
1809
1810 return symbol;
1811 }
1812 #endif
1813 \f
1814 /* A and B are either alignments or offsets. Return the minimum alignment
1815 that may be assumed after adding the two together. */
1816
1817 static inline unsigned
1818 min_align (unsigned int a, unsigned int b)
1819 {
1820 return (a | b) & -(a | b);
1821 }
1822
1823 /* Return the assembler directive for creating a given kind of integer
1824 object. SIZE is the number of bytes in the object and ALIGNED_P
1825 indicates whether it is known to be aligned. Return NULL if the
1826 assembly dialect has no such directive.
1827
1828 The returned string should be printed at the start of a new line and
1829 be followed immediately by the object's initial value. */
1830
1831 const char *
1832 integer_asm_op (int size, int aligned_p)
1833 {
1834 struct asm_int_op *ops;
1835
1836 if (aligned_p)
1837 ops = &targetm.asm_out.aligned_op;
1838 else
1839 ops = &targetm.asm_out.unaligned_op;
1840
1841 switch (size)
1842 {
1843 case 1:
1844 return targetm.asm_out.byte_op;
1845 case 2:
1846 return ops->hi;
1847 case 4:
1848 return ops->si;
1849 case 8:
1850 return ops->di;
1851 case 16:
1852 return ops->ti;
1853 default:
1854 return NULL;
1855 }
1856 }
1857
1858 /* Use directive OP to assemble an integer object X. Print OP at the
1859 start of the line, followed immediately by the value of X. */
1860
1861 void
1862 assemble_integer_with_op (const char *op, rtx x)
1863 {
1864 fputs (op, asm_out_file);
1865 output_addr_const (asm_out_file, x);
1866 fputc ('\n', asm_out_file);
1867 }
1868
1869 /* The default implementation of the asm_out.integer target hook. */
1870
1871 bool
1872 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
1873 unsigned int size ATTRIBUTE_UNUSED,
1874 int aligned_p ATTRIBUTE_UNUSED)
1875 {
1876 const char *op = integer_asm_op (size, aligned_p);
1877 return op && (assemble_integer_with_op (op, x), true);
1878 }
1879
1880 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
1881 the alignment of the integer in bits. Return 1 if we were able to output
1882 the constant, otherwise 0. If FORCE is nonzero, abort if we can't output
1883 the constant. */
1884
1885 bool
1886 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
1887 {
1888 int aligned_p;
1889
1890 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
1891
1892 /* See if the target hook can handle this kind of object. */
1893 if (targetm.asm_out.integer (x, size, aligned_p))
1894 return true;
1895
1896 /* If the object is a multi-byte one, try splitting it up. Split
1897 it into words it if is multi-word, otherwise split it into bytes. */
1898 if (size > 1)
1899 {
1900 enum machine_mode omode, imode;
1901 unsigned int subalign;
1902 unsigned int subsize, i;
1903
1904 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
1905 subalign = MIN (align, subsize * BITS_PER_UNIT);
1906 omode = mode_for_size (subsize * BITS_PER_UNIT, MODE_INT, 0);
1907 imode = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
1908
1909 for (i = 0; i < size; i += subsize)
1910 {
1911 rtx partial = simplify_subreg (omode, x, imode, i);
1912 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
1913 break;
1914 }
1915 if (i == size)
1916 return true;
1917
1918 /* If we've printed some of it, but not all of it, there's no going
1919 back now. */
1920 if (i > 0)
1921 abort ();
1922 }
1923
1924 if (force)
1925 abort ();
1926
1927 return false;
1928 }
1929 \f
1930 void
1931 assemble_real (REAL_VALUE_TYPE d, enum machine_mode mode, unsigned int align)
1932 {
1933 long data[4];
1934 int i;
1935 int bitsize, nelts, nunits, units_per;
1936
1937 /* This is hairy. We have a quantity of known size. real_to_target
1938 will put it into an array of *host* longs, 32 bits per element
1939 (even if long is more than 32 bits). We need to determine the
1940 number of array elements that are occupied (nelts) and the number
1941 of *target* min-addressable units that will be occupied in the
1942 object file (nunits). We cannot assume that 32 divides the
1943 mode's bitsize (size * BITS_PER_UNIT) evenly.
1944
1945 size * BITS_PER_UNIT is used here to make sure that padding bits
1946 (which might appear at either end of the value; real_to_target
1947 will include the padding bits in its output array) are included. */
1948
1949 nunits = GET_MODE_SIZE (mode);
1950 bitsize = nunits * BITS_PER_UNIT;
1951 nelts = CEIL (bitsize, 32);
1952 units_per = 32 / BITS_PER_UNIT;
1953
1954 real_to_target (data, &d, mode);
1955
1956 /* Put out the first word with the specified alignment. */
1957 assemble_integer (GEN_INT (data[0]), MIN (nunits, units_per), align, 1);
1958 nunits -= units_per;
1959
1960 /* Subsequent words need only 32-bit alignment. */
1961 align = min_align (align, 32);
1962
1963 for (i = 1; i < nelts; i++)
1964 {
1965 assemble_integer (GEN_INT (data[i]), MIN (nunits, units_per), align, 1);
1966 nunits -= units_per;
1967 }
1968 }
1969 \f
1970 /* Given an expression EXP with a constant value,
1971 reduce it to the sum of an assembler symbol and an integer.
1972 Store them both in the structure *VALUE.
1973 Abort if EXP does not reduce. */
1974
1975 struct addr_const GTY(())
1976 {
1977 rtx base;
1978 HOST_WIDE_INT offset;
1979 };
1980
1981 static void
1982 decode_addr_const (tree exp, struct addr_const *value)
1983 {
1984 tree target = TREE_OPERAND (exp, 0);
1985 int offset = 0;
1986 rtx x;
1987
1988 while (1)
1989 {
1990 if (TREE_CODE (target) == COMPONENT_REF
1991 && host_integerp (byte_position (TREE_OPERAND (target, 1)), 0))
1992
1993 {
1994 offset += int_byte_position (TREE_OPERAND (target, 1));
1995 target = TREE_OPERAND (target, 0);
1996 }
1997 else if (TREE_CODE (target) == ARRAY_REF
1998 || TREE_CODE (target) == ARRAY_RANGE_REF)
1999 {
2000 offset += (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (target)), 1)
2001 * tree_low_cst (TREE_OPERAND (target, 1), 0));
2002 target = TREE_OPERAND (target, 0);
2003 }
2004 else
2005 break;
2006 }
2007
2008 switch (TREE_CODE (target))
2009 {
2010 case VAR_DECL:
2011 case FUNCTION_DECL:
2012 x = DECL_RTL (target);
2013 break;
2014
2015 case LABEL_DECL:
2016 x = gen_rtx_MEM (FUNCTION_MODE,
2017 gen_rtx_LABEL_REF (VOIDmode, force_label_rtx (target)));
2018 break;
2019
2020 case REAL_CST:
2021 case STRING_CST:
2022 case COMPLEX_CST:
2023 case CONSTRUCTOR:
2024 case INTEGER_CST:
2025 x = output_constant_def (target, 1);
2026 break;
2027
2028 default:
2029 abort ();
2030 }
2031
2032 if (GET_CODE (x) != MEM)
2033 abort ();
2034 x = XEXP (x, 0);
2035
2036 value->base = x;
2037 value->offset = offset;
2038 }
2039 \f
2040 /* Uniquize all constants that appear in memory.
2041 Each constant in memory thus far output is recorded
2042 in `const_desc_table'. */
2043
2044 struct constant_descriptor_tree GTY(())
2045 {
2046 /* A MEM for the constant. */
2047 rtx rtl;
2048
2049 /* The value of the constant. */
2050 tree value;
2051 };
2052
2053 static GTY((param_is (struct constant_descriptor_tree)))
2054 htab_t const_desc_htab;
2055
2056 static struct constant_descriptor_tree * build_constant_desc (tree);
2057 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2058
2059 /* Compute a hash code for a constant expression. */
2060
2061 static hashval_t
2062 const_desc_hash (const void *ptr)
2063 {
2064 return const_hash_1 (((struct constant_descriptor_tree *)ptr)->value);
2065 }
2066
2067 static hashval_t
2068 const_hash_1 (const tree exp)
2069 {
2070 const char *p;
2071 hashval_t hi;
2072 int len, i;
2073 enum tree_code code = TREE_CODE (exp);
2074
2075 /* Either set P and LEN to the address and len of something to hash and
2076 exit the switch or return a value. */
2077
2078 switch (code)
2079 {
2080 case INTEGER_CST:
2081 p = (char *) &TREE_INT_CST (exp);
2082 len = sizeof TREE_INT_CST (exp);
2083 break;
2084
2085 case REAL_CST:
2086 return real_hash (TREE_REAL_CST_PTR (exp));
2087
2088 case STRING_CST:
2089 p = TREE_STRING_POINTER (exp);
2090 len = TREE_STRING_LENGTH (exp);
2091 break;
2092
2093 case COMPLEX_CST:
2094 return (const_hash_1 (TREE_REALPART (exp)) * 5
2095 + const_hash_1 (TREE_IMAGPART (exp)));
2096
2097 case CONSTRUCTOR:
2098 if (TREE_CODE (TREE_TYPE (exp)) == SET_TYPE)
2099 {
2100 char *tmp;
2101
2102 len = int_size_in_bytes (TREE_TYPE (exp));
2103 tmp = alloca (len);
2104 get_set_constructor_bytes (exp, (unsigned char *) tmp, len);
2105 p = tmp;
2106 break;
2107 }
2108 else
2109 {
2110 tree link;
2111
2112 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2113
2114 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link))
2115 if (TREE_VALUE (link))
2116 hi = hi * 603 + const_hash_1 (TREE_VALUE (link));
2117
2118 return hi;
2119 }
2120
2121 case ADDR_EXPR:
2122 case FDESC_EXPR:
2123 {
2124 struct addr_const value;
2125
2126 decode_addr_const (exp, &value);
2127 if (GET_CODE (value.base) == SYMBOL_REF)
2128 {
2129 /* Don't hash the address of the SYMBOL_REF;
2130 only use the offset and the symbol name. */
2131 hi = value.offset;
2132 p = XSTR (value.base, 0);
2133 for (i = 0; p[i] != 0; i++)
2134 hi = ((hi * 613) + (unsigned) (p[i]));
2135 }
2136 else if (GET_CODE (value.base) == LABEL_REF)
2137 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13;
2138 else
2139 abort ();
2140 }
2141 return hi;
2142
2143 case PLUS_EXPR:
2144 case MINUS_EXPR:
2145 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2146 + const_hash_1 (TREE_OPERAND (exp, 1)));
2147
2148 case NOP_EXPR:
2149 case CONVERT_EXPR:
2150 case NON_LVALUE_EXPR:
2151 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
2152
2153 default:
2154 /* A language specific constant. Just hash the code. */
2155 return code;
2156 }
2157
2158 /* Compute hashing function. */
2159 hi = len;
2160 for (i = 0; i < len; i++)
2161 hi = ((hi * 613) + (unsigned) (p[i]));
2162
2163 return hi;
2164 }
2165
2166 /* Wrapper of compare_constant, for the htab interface. */
2167 static int
2168 const_desc_eq (const void *p1, const void *p2)
2169 {
2170 return compare_constant (((struct constant_descriptor_tree *)p1)->value,
2171 ((struct constant_descriptor_tree *)p2)->value);
2172 }
2173
2174 /* Compare t1 and t2, and return 1 only if they are known to result in
2175 the same bit pattern on output. */
2176
2177 static int
2178 compare_constant (const tree t1, const tree t2)
2179 {
2180 enum tree_code typecode;
2181
2182 if (t1 == NULL_TREE)
2183 return t2 == NULL_TREE;
2184 if (t2 == NULL_TREE)
2185 return 0;
2186
2187 if (TREE_CODE (t1) != TREE_CODE (t2))
2188 return 0;
2189
2190 switch (TREE_CODE (t1))
2191 {
2192 case INTEGER_CST:
2193 /* Integer constants are the same only if the same width of type. */
2194 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2195 return 0;
2196 return tree_int_cst_equal (t1, t2);
2197
2198 case REAL_CST:
2199 /* Real constants are the same only if the same width of type. */
2200 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2201 return 0;
2202
2203 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
2204
2205 case STRING_CST:
2206 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2207 return 0;
2208
2209 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
2210 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
2211 TREE_STRING_LENGTH (t1)));
2212
2213 case COMPLEX_CST:
2214 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
2215 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
2216
2217 case CONSTRUCTOR:
2218 typecode = TREE_CODE (TREE_TYPE (t1));
2219 if (typecode != TREE_CODE (TREE_TYPE (t2)))
2220 return 0;
2221
2222 if (typecode == SET_TYPE)
2223 {
2224 int len = int_size_in_bytes (TREE_TYPE (t2));
2225 unsigned char *tmp1, *tmp2;
2226
2227 if (int_size_in_bytes (TREE_TYPE (t1)) != len)
2228 return 0;
2229
2230 tmp1 = alloca (len);
2231 tmp2 = alloca (len);
2232
2233 if (get_set_constructor_bytes (t1, tmp1, len) != NULL_TREE)
2234 return 0;
2235 if (get_set_constructor_bytes (t2, tmp2, len) != NULL_TREE)
2236 return 0;
2237
2238 return memcmp (tmp1, tmp2, len) == 0;
2239 }
2240 else
2241 {
2242 tree l1, l2;
2243
2244 if (typecode == ARRAY_TYPE)
2245 {
2246 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
2247 /* For arrays, check that the sizes all match. */
2248 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
2249 || size_1 == -1
2250 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
2251 return 0;
2252 }
2253 else
2254 {
2255 /* For record and union constructors, require exact type
2256 equality. */
2257 if (TREE_TYPE (t1) != TREE_TYPE (t2))
2258 return 0;
2259 }
2260
2261 for (l1 = CONSTRUCTOR_ELTS (t1), l2 = CONSTRUCTOR_ELTS (t2);
2262 l1 && l2;
2263 l1 = TREE_CHAIN (l1), l2 = TREE_CHAIN (l2))
2264 {
2265 /* Check that each value is the same... */
2266 if (! compare_constant (TREE_VALUE (l1), TREE_VALUE (l2)))
2267 return 0;
2268 /* ... and that they apply to the same fields! */
2269 if (typecode == ARRAY_TYPE)
2270 {
2271 if (! compare_constant (TREE_PURPOSE (l1),
2272 TREE_PURPOSE (l2)))
2273 return 0;
2274 }
2275 else
2276 {
2277 if (TREE_PURPOSE (l1) != TREE_PURPOSE (l2))
2278 return 0;
2279 }
2280 }
2281
2282 return l1 == NULL_TREE && l2 == NULL_TREE;
2283 }
2284
2285 case ADDR_EXPR:
2286 case FDESC_EXPR:
2287 {
2288 struct addr_const value1, value2;
2289
2290 decode_addr_const (t1, &value1);
2291 decode_addr_const (t2, &value2);
2292 return (value1.offset == value2.offset
2293 && strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
2294 }
2295
2296 case PLUS_EXPR:
2297 case MINUS_EXPR:
2298 case RANGE_EXPR:
2299 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
2300 && compare_constant(TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
2301
2302 case NOP_EXPR:
2303 case CONVERT_EXPR:
2304 case NON_LVALUE_EXPR:
2305 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
2306
2307 default:
2308 {
2309 tree nt1, nt2;
2310 nt1 = lang_hooks.expand_constant (t1);
2311 nt2 = lang_hooks.expand_constant (t2);
2312 if (nt1 != t1 || nt2 != t2)
2313 return compare_constant (nt1, nt2);
2314 else
2315 return 0;
2316 }
2317 }
2318
2319 /* Should not get here. */
2320 abort ();
2321 }
2322 \f
2323 /* Make a copy of the whole tree structure for a constant. This
2324 handles the same types of nodes that compare_constant handles. */
2325
2326 static tree
2327 copy_constant (tree exp)
2328 {
2329 switch (TREE_CODE (exp))
2330 {
2331 case ADDR_EXPR:
2332 /* For ADDR_EXPR, we do not want to copy the decl whose address
2333 is requested. We do want to copy constants though. */
2334 if (TREE_CODE_CLASS (TREE_CODE (TREE_OPERAND (exp, 0))) == 'c')
2335 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
2336 copy_constant (TREE_OPERAND (exp, 0)));
2337 else
2338 return copy_node (exp);
2339
2340 case INTEGER_CST:
2341 case REAL_CST:
2342 case STRING_CST:
2343 return copy_node (exp);
2344
2345 case COMPLEX_CST:
2346 return build_complex (TREE_TYPE (exp),
2347 copy_constant (TREE_REALPART (exp)),
2348 copy_constant (TREE_IMAGPART (exp)));
2349
2350 case PLUS_EXPR:
2351 case MINUS_EXPR:
2352 return build (TREE_CODE (exp), TREE_TYPE (exp),
2353 copy_constant (TREE_OPERAND (exp, 0)),
2354 copy_constant (TREE_OPERAND (exp, 1)));
2355
2356 case NOP_EXPR:
2357 case CONVERT_EXPR:
2358 case NON_LVALUE_EXPR:
2359 case VIEW_CONVERT_EXPR:
2360 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
2361 copy_constant (TREE_OPERAND (exp, 0)));
2362
2363 case CONSTRUCTOR:
2364 {
2365 tree copy = copy_node (exp);
2366 tree list = copy_list (CONSTRUCTOR_ELTS (exp));
2367 tree tail;
2368
2369 CONSTRUCTOR_ELTS (copy) = list;
2370 for (tail = list; tail; tail = TREE_CHAIN (tail))
2371 TREE_VALUE (tail) = copy_constant (TREE_VALUE (tail));
2372 if (TREE_CODE (TREE_TYPE (exp)) == SET_TYPE)
2373 for (tail = list; tail; tail = TREE_CHAIN (tail))
2374 TREE_PURPOSE (tail) = copy_constant (TREE_PURPOSE (tail));
2375
2376 return copy;
2377 }
2378
2379 default:
2380 {
2381 tree t;
2382 t = lang_hooks.expand_constant (exp);
2383 if (t != exp)
2384 return copy_constant (t);
2385 else
2386 abort ();
2387 }
2388 }
2389 }
2390 \f
2391 /* Subroutine of output_constant_def:
2392 No constant equal to EXP is known to have been output.
2393 Make a constant descriptor to enter EXP in the hash table.
2394 Assign the label number and construct RTL to refer to the
2395 constant's location in memory.
2396 Caller is responsible for updating the hash table. */
2397
2398 static struct constant_descriptor_tree *
2399 build_constant_desc (tree exp)
2400 {
2401 rtx symbol;
2402 rtx rtl;
2403 char label[256];
2404 int labelno;
2405 struct constant_descriptor_tree *desc;
2406
2407 desc = ggc_alloc (sizeof (*desc));
2408 desc->value = copy_constant (exp);
2409
2410 /* Create a string containing the label name, in LABEL. */
2411 labelno = const_labelno++;
2412 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
2413
2414 /* We have a symbol name; construct the SYMBOL_REF and the MEM. */
2415 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
2416 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2417 SYMBOL_REF_DECL (symbol) = desc->value;
2418 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
2419
2420 rtl = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)), symbol);
2421 set_mem_attributes (rtl, exp, 1);
2422 set_mem_alias_set (rtl, 0);
2423 set_mem_alias_set (rtl, const_alias_set);
2424
2425 /* Set flags or add text to the name to record information, such as
2426 that it is a local symbol. If the name is changed, the macro
2427 ASM_OUTPUT_LABELREF will have to know how to strip this
2428 information. This call might invalidate our local variable
2429 SYMBOL; we can't use it afterward. */
2430
2431 targetm.encode_section_info (exp, rtl, true);
2432
2433 desc->rtl = rtl;
2434
2435 return desc;
2436 }
2437
2438 /* Return an rtx representing a reference to constant data in memory
2439 for the constant expression EXP.
2440
2441 If assembler code for such a constant has already been output,
2442 return an rtx to refer to it.
2443 Otherwise, output such a constant in memory
2444 and generate an rtx for it.
2445
2446 If DEFER is nonzero, this constant can be deferred and output only
2447 if referenced in the function after all optimizations.
2448
2449 `const_desc_table' records which constants already have label strings. */
2450
2451 rtx
2452 output_constant_def (tree exp, int defer)
2453 {
2454 struct constant_descriptor_tree *desc;
2455 struct constant_descriptor_tree key;
2456 void **loc;
2457
2458 /* Look up EXP in the table of constant descriptors. If we didn't find
2459 it, create a new one. */
2460 key.value = exp;
2461 loc = htab_find_slot (const_desc_htab, &key, INSERT);
2462
2463 desc = *loc;
2464 if (desc == 0)
2465 {
2466 desc = build_constant_desc (exp);
2467 *loc = desc;
2468 }
2469
2470 maybe_output_constant_def_contents (desc, defer);
2471 return desc->rtl;
2472 }
2473
2474 /* Subroutine of output_constant_def: Decide whether or not we need to
2475 output the constant DESC now, and if so, do it. */
2476 static void
2477 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
2478 int defer)
2479 {
2480 rtx symbol = XEXP (desc->rtl, 0);
2481 tree exp = desc->value;
2482
2483 if (flag_syntax_only)
2484 return;
2485
2486 if (TREE_ASM_WRITTEN (exp))
2487 /* Already output; don't do it again. */
2488 return;
2489
2490 /* We can always defer constants as long as the context allows
2491 doing so. */
2492 if (defer)
2493 {
2494 /* Increment n_deferred_constants if it exists. It needs to be at
2495 least as large as the number of constants actually referred to
2496 by the function. If it's too small we'll stop looking too early
2497 and fail to emit constants; if it's too large we'll only look
2498 through the entire function when we could have stopped earlier. */
2499 if (cfun)
2500 n_deferred_constants++;
2501 return;
2502 }
2503
2504 output_constant_def_contents (symbol);
2505 }
2506
2507 /* We must output the constant data referred to by SYMBOL; do so. */
2508
2509 static void
2510 output_constant_def_contents (rtx symbol)
2511 {
2512 tree exp = SYMBOL_REF_DECL (symbol);
2513 const char *label = XSTR (symbol, 0);
2514 HOST_WIDE_INT size;
2515
2516 /* Make sure any other constants whose addresses appear in EXP
2517 are assigned label numbers. */
2518 int reloc = compute_reloc_for_constant (exp);
2519
2520 /* Align the location counter as required by EXP's data type. */
2521 int align = TYPE_ALIGN (TREE_TYPE (exp));
2522 #ifdef CONSTANT_ALIGNMENT
2523 align = CONSTANT_ALIGNMENT (exp, align);
2524 #endif
2525
2526 output_addressed_constants (exp);
2527
2528 /* We are no longer deferring this constant. */
2529 TREE_ASM_WRITTEN (exp) = 1;
2530
2531 if (IN_NAMED_SECTION (exp))
2532 named_section (exp, NULL, reloc);
2533 else
2534 targetm.asm_out.select_section (exp, reloc, align);
2535
2536 if (align > BITS_PER_UNIT)
2537 {
2538 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2539 }
2540
2541 size = int_size_in_bytes (TREE_TYPE (exp));
2542 if (TREE_CODE (exp) == STRING_CST)
2543 size = MAX (TREE_STRING_LENGTH (exp), size);
2544
2545 /* Do any machine/system dependent processing of the constant. */
2546 #ifdef ASM_DECLARE_CONSTANT_NAME
2547 ASM_DECLARE_CONSTANT_NAME (asm_out_file, label, exp, size);
2548 #else
2549 /* Standard thing is just output label for the constant. */
2550 ASM_OUTPUT_LABEL (asm_out_file, label);
2551 #endif /* ASM_DECLARE_CONSTANT_NAME */
2552
2553 /* Output the value of EXP. */
2554 output_constant (exp, size, align);
2555 }
2556
2557 /* A constant which was deferred in its original location has been
2558 inserted by the RTL inliner into a different function. The
2559 current function's deferred constant count must be incremented. */
2560 void
2561 notice_rtl_inlining_of_deferred_constant (void)
2562 {
2563 n_deferred_constants++;
2564 }
2565
2566 /* Look up EXP in the table of constant descriptors. Return the rtl
2567 if it has been emitted, else null. */
2568
2569 rtx
2570 lookup_constant_def (tree exp)
2571 {
2572 struct constant_descriptor_tree *desc;
2573 struct constant_descriptor_tree key;
2574
2575 key.value = exp;
2576 desc = htab_find (const_desc_htab, &key);
2577
2578 return (desc ? desc->rtl : NULL_RTX);
2579 }
2580 \f
2581 /* Used in the hash tables to avoid outputting the same constant
2582 twice. Unlike 'struct constant_descriptor_tree', RTX constants
2583 are output once per function, not once per file. */
2584 /* ??? Only a few targets need per-function constant pools. Most
2585 can use one per-file pool. Should add a targetm bit to tell the
2586 difference. */
2587
2588 struct rtx_constant_pool GTY(())
2589 {
2590 /* Pointers to first and last constant in pool, as ordered by offset. */
2591 struct constant_descriptor_rtx *first;
2592 struct constant_descriptor_rtx *last;
2593
2594 /* Hash facility for making memory-constants from constant rtl-expressions.
2595 It is used on RISC machines where immediate integer arguments and
2596 constant addresses are restricted so that such constants must be stored
2597 in memory. */
2598 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_htab;
2599 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_sym_htab;
2600
2601 /* Current offset in constant pool (does not include any
2602 machine-specific header). */
2603 HOST_WIDE_INT offset;
2604 };
2605
2606 struct constant_descriptor_rtx GTY((chain_next ("%h.next")))
2607 {
2608 struct constant_descriptor_rtx *next;
2609 rtx mem;
2610 rtx sym;
2611 rtx constant;
2612 HOST_WIDE_INT offset;
2613 hashval_t hash;
2614 enum machine_mode mode;
2615 unsigned int align;
2616 int labelno;
2617 int mark;
2618 };
2619
2620 /* Hash and compare functions for const_rtx_htab. */
2621
2622 static hashval_t
2623 const_desc_rtx_hash (const void *ptr)
2624 {
2625 const struct constant_descriptor_rtx *desc = ptr;
2626 return desc->hash;
2627 }
2628
2629 static int
2630 const_desc_rtx_eq (const void *a, const void *b)
2631 {
2632 const struct constant_descriptor_rtx *x = a;
2633 const struct constant_descriptor_rtx *y = b;
2634
2635 if (x->mode != y->mode)
2636 return 0;
2637 return rtx_equal_p (x->constant, y->constant);
2638 }
2639
2640 /* Hash and compare functions for const_rtx_sym_htab. */
2641
2642 static hashval_t
2643 const_desc_rtx_sym_hash (const void *ptr)
2644 {
2645 const struct constant_descriptor_rtx *desc = ptr;
2646 return htab_hash_string (XSTR (desc->sym, 0));
2647 }
2648
2649 static int
2650 const_desc_rtx_sym_eq (const void *a, const void *b)
2651 {
2652 const struct constant_descriptor_rtx *x = a;
2653 const struct constant_descriptor_rtx *y = b;
2654 return XSTR (x->sym, 0) == XSTR (y->sym, 0);
2655 }
2656
2657 /* This is the worker function for const_rtx_hash, called via for_each_rtx. */
2658
2659 static int
2660 const_rtx_hash_1 (rtx *xp, void *data)
2661 {
2662 unsigned HOST_WIDE_INT hwi;
2663 enum machine_mode mode;
2664 enum rtx_code code;
2665 hashval_t h, *hp;
2666 rtx x;
2667
2668 x = *xp;
2669 code = GET_CODE (x);
2670 mode = GET_MODE (x);
2671 h = (hashval_t) code * 1048573 + mode;
2672
2673 switch (code)
2674 {
2675 case CONST_INT:
2676 hwi = INTVAL (x);
2677 fold_hwi:
2678 {
2679 const int shift = sizeof (hashval_t) * CHAR_BIT;
2680 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
2681 int i;
2682
2683 h ^= (hashval_t) hwi;
2684 for (i = 1; i < n; ++i)
2685 {
2686 hwi >>= shift;
2687 h ^= (hashval_t) hwi;
2688 }
2689 }
2690 break;
2691
2692 case CONST_DOUBLE:
2693 if (mode == VOIDmode)
2694 {
2695 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
2696 goto fold_hwi;
2697 }
2698 else
2699 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
2700 break;
2701
2702 case SYMBOL_REF:
2703 h ^= htab_hash_string (XSTR (x, 0));
2704 break;
2705
2706 case LABEL_REF:
2707 h = h * 251 + CODE_LABEL_NUMBER (XEXP (x, 0));
2708 break;
2709
2710 case UNSPEC:
2711 case UNSPEC_VOLATILE:
2712 h = h * 251 + XINT (x, 1);
2713 break;
2714
2715 default:
2716 break;
2717 }
2718
2719 hp = data;
2720 *hp = *hp * 509 + h;
2721 return 0;
2722 }
2723
2724 /* Compute a hash value for X, which should be a constant. */
2725
2726 static hashval_t
2727 const_rtx_hash (rtx x)
2728 {
2729 hashval_t h = 0;
2730 for_each_rtx (&x, const_rtx_hash_1, &h);
2731 return h;
2732 }
2733
2734 \f
2735 /* Initialize constant pool hashing for a new function. */
2736
2737 void
2738 init_varasm_status (struct function *f)
2739 {
2740 struct varasm_status *p;
2741 struct rtx_constant_pool *pool;
2742
2743 p = ggc_alloc (sizeof (struct varasm_status));
2744 f->varasm = p;
2745
2746 pool = ggc_alloc (sizeof (struct rtx_constant_pool));
2747 p->pool = pool;
2748 p->deferred_constants = 0;
2749
2750 pool->const_rtx_htab = htab_create_ggc (31, const_desc_rtx_hash,
2751 const_desc_rtx_eq, NULL);
2752 pool->const_rtx_sym_htab = htab_create_ggc (31, const_desc_rtx_sym_hash,
2753 const_desc_rtx_sym_eq, NULL);
2754 pool->first = pool->last = NULL;
2755 pool->offset = 0;
2756 }
2757 \f
2758 /* Given a MINUS expression, simplify it if both sides
2759 include the same symbol. */
2760
2761 rtx
2762 simplify_subtraction (rtx x)
2763 {
2764 rtx r = simplify_rtx (x);
2765 return r ? r : x;
2766 }
2767 \f
2768 /* Given a constant rtx X, make (or find) a memory constant for its value
2769 and return a MEM rtx to refer to it in memory. */
2770
2771 rtx
2772 force_const_mem (enum machine_mode mode, rtx x)
2773 {
2774 struct constant_descriptor_rtx *desc, tmp;
2775 struct rtx_constant_pool *pool = cfun->varasm->pool;
2776 char label[256];
2777 rtx def, symbol;
2778 hashval_t hash;
2779 unsigned int align;
2780 void **slot;
2781
2782 /* If we're not allowed to drop X into the constant pool, don't. */
2783 if (targetm.cannot_force_const_mem (x))
2784 return NULL_RTX;
2785
2786 /* Lookup the value in the hashtable. */
2787 tmp.constant = x;
2788 tmp.mode = mode;
2789 hash = const_rtx_hash (x);
2790 slot = htab_find_slot_with_hash (pool->const_rtx_htab, &tmp, hash, INSERT);
2791 desc = *slot;
2792
2793 /* If the constant was already present, return its memory. */
2794 if (desc)
2795 return copy_rtx (desc->mem);
2796
2797 /* Otherwise, create a new descriptor. */
2798 desc = ggc_alloc (sizeof (*desc));
2799 *slot = desc;
2800
2801 /* Align the location counter as required by EXP's data type. */
2802 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
2803 #ifdef CONSTANT_ALIGNMENT
2804 {
2805 tree type = lang_hooks.types.type_for_mode (mode, 0);
2806 if (type != NULL_TREE)
2807 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
2808 }
2809 #endif
2810
2811 pool->offset += (align / BITS_PER_UNIT) - 1;
2812 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
2813
2814 desc->next = NULL;
2815 desc->constant = tmp.constant;
2816 desc->offset = pool->offset;
2817 desc->hash = hash;
2818 desc->mode = mode;
2819 desc->align = align;
2820 desc->labelno = const_labelno;
2821 desc->mark = 0;
2822
2823 pool->offset += GET_MODE_SIZE (mode);
2824 if (pool->last)
2825 pool->last->next = desc;
2826 else
2827 pool->first = pool->last = desc;
2828 pool->last = desc;
2829
2830 /* Create a string containing the label name, in LABEL. */
2831 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
2832 ++const_labelno;
2833
2834 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
2835 the constants pool. */
2836 desc->sym = symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
2837 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2838 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
2839 current_function_uses_const_pool = 1;
2840
2841 /* Insert the descriptor into the symbol cross-reference table too. */
2842 slot = htab_find_slot (pool->const_rtx_sym_htab, desc, INSERT);
2843 if (*slot)
2844 abort ();
2845 *slot = desc;
2846
2847 /* Construct the MEM. */
2848 desc->mem = def = gen_rtx_MEM (mode, symbol);
2849 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
2850 RTX_UNCHANGING_P (def) = 1;
2851
2852 /* If we're dropping a label to the constant pool, make sure we
2853 don't delete it. */
2854 if (GET_CODE (x) == LABEL_REF)
2855 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
2856
2857 return copy_rtx (def);
2858 }
2859 \f
2860 /* Given a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true, return a pointer to
2861 the corresponding constant_descriptor_rtx structure. */
2862
2863 static struct constant_descriptor_rtx *
2864 find_pool_constant (struct rtx_constant_pool *pool, rtx sym)
2865 {
2866 struct constant_descriptor_rtx tmp;
2867 tmp.sym = sym;
2868 return htab_find (pool->const_rtx_sym_htab, &tmp);
2869 }
2870
2871 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
2872
2873 rtx
2874 get_pool_constant (rtx addr)
2875 {
2876 return find_pool_constant (cfun->varasm->pool, addr)->constant;
2877 }
2878
2879 /* Given a constant pool SYMBOL_REF, return the corresponding constant
2880 and whether it has been output or not. */
2881
2882 rtx
2883 get_pool_constant_mark (rtx addr, bool *pmarked)
2884 {
2885 struct constant_descriptor_rtx *desc;
2886
2887 desc = find_pool_constant (cfun->varasm->pool, addr);
2888 *pmarked = (desc->mark != 0);
2889 return desc->constant;
2890 }
2891
2892 /* Likewise, but for the constant pool of a specific function. */
2893
2894 rtx
2895 get_pool_constant_for_function (struct function *f, rtx addr)
2896 {
2897 return find_pool_constant (f->varasm->pool, addr)->constant;
2898 }
2899
2900 /* Similar, return the mode. */
2901
2902 enum machine_mode
2903 get_pool_mode (rtx addr)
2904 {
2905 return find_pool_constant (cfun->varasm->pool, addr)->mode;
2906 }
2907
2908 enum machine_mode
2909 get_pool_mode_for_function (struct function *f, rtx addr)
2910 {
2911 return find_pool_constant (f->varasm->pool, addr)->mode;
2912 }
2913
2914 /* Similar, return the offset in the constant pool. */
2915
2916 int
2917 get_pool_offset (rtx addr)
2918 {
2919 return find_pool_constant (cfun->varasm->pool, addr)->offset;
2920 }
2921
2922 /* Return the size of the constant pool. */
2923
2924 int
2925 get_pool_size (void)
2926 {
2927 return cfun->varasm->pool->offset;
2928 }
2929 \f
2930 /* Worker function for output_constant_pool_1. Emit assembly for X
2931 in MODE with known alignment ALIGN. */
2932
2933 static void
2934 output_constant_pool_2 (enum machine_mode mode, rtx x, unsigned int align)
2935 {
2936 switch (GET_MODE_CLASS (mode))
2937 {
2938 case MODE_FLOAT:
2939 if (GET_CODE (x) != CONST_DOUBLE)
2940 abort ();
2941 else
2942 {
2943 REAL_VALUE_TYPE r;
2944 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
2945 assemble_real (r, mode, align);
2946 }
2947 break;
2948
2949 case MODE_INT:
2950 case MODE_PARTIAL_INT:
2951 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
2952 break;
2953
2954 case MODE_VECTOR_FLOAT:
2955 case MODE_VECTOR_INT:
2956 {
2957 int i, units;
2958 enum machine_mode submode = GET_MODE_INNER (mode);
2959 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
2960
2961 if (GET_CODE (x) != CONST_VECTOR)
2962 abort ();
2963 units = CONST_VECTOR_NUNITS (x);
2964
2965 for (i = 0; i < units; i++)
2966 {
2967 rtx elt = CONST_VECTOR_ELT (x, i);
2968 output_constant_pool_2 (submode, elt, i ? subalign : align);
2969 }
2970 }
2971 break;
2972
2973 default:
2974 abort ();
2975 }
2976 }
2977
2978 /* Worker function for output_constant_pool. Emit POOL. */
2979
2980 static void
2981 output_constant_pool_1 (struct constant_descriptor_rtx *desc)
2982 {
2983 rtx x, tmp;
2984
2985 if (!desc->mark)
2986 return;
2987 x = desc->constant;
2988
2989 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
2990 whose CODE_LABEL has been deleted. This can occur if a jump table
2991 is eliminated by optimization. If so, write a constant of zero
2992 instead. Note that this can also happen by turning the
2993 CODE_LABEL into a NOTE. */
2994 /* ??? This seems completely and utterly wrong. Certainly it's
2995 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
2996 functioning even with INSN_DELETED_P and friends. */
2997
2998 tmp = x;
2999 switch (GET_CODE (x))
3000 {
3001 case CONST:
3002 if (GET_CODE (XEXP (x, 0)) != PLUS
3003 || GET_CODE (XEXP (XEXP (x, 0), 0)) != LABEL_REF)
3004 break;
3005 tmp = XEXP (XEXP (x, 0), 0);
3006 /* FALLTHRU */
3007
3008 case LABEL_REF:
3009 tmp = XEXP (x, 0);
3010 if (INSN_DELETED_P (tmp)
3011 || (GET_CODE (tmp) == NOTE
3012 && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_DELETED))
3013 {
3014 abort ();
3015 x = const0_rtx;
3016 }
3017 break;
3018
3019 default:
3020 break;
3021 }
3022
3023 /* First switch to correct section. */
3024 targetm.asm_out.select_rtx_section (desc->mode, x, desc->align);
3025
3026 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3027 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3028 desc->align, desc->labelno, done);
3029 #endif
3030
3031 assemble_align (desc->align);
3032
3033 /* Output the label. */
3034 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3035
3036 /* Output the data. */
3037 output_constant_pool_2 (desc->mode, x, desc->align);
3038
3039 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3040 sections have proper size. */
3041 if (desc->align > GET_MODE_BITSIZE (desc->mode)
3042 && in_section == in_named
3043 && get_named_section_flags (in_named_name) & SECTION_MERGE)
3044 assemble_align (desc->align);
3045
3046 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3047 done:
3048 #endif
3049 return;
3050 }
3051
3052 /* Given a SYMBOL_REF CURRENT_RTX, mark it and all constants it refers
3053 to as used. Emit referenced deferred strings. This function can
3054 be used with for_each_rtx to mark all SYMBOL_REFs in an rtx. */
3055
3056 static int
3057 mark_constant (rtx *current_rtx, void *data)
3058 {
3059 struct rtx_constant_pool *pool = data;
3060 rtx x = *current_rtx;
3061
3062 if (x == NULL_RTX || GET_CODE (x) != SYMBOL_REF)
3063 return 0;
3064
3065 if (CONSTANT_POOL_ADDRESS_P (x))
3066 {
3067 struct constant_descriptor_rtx *desc = find_pool_constant (pool, x);
3068 if (desc->mark == 0)
3069 {
3070 desc->mark = 1;
3071 for_each_rtx (&desc->constant, mark_constant, pool);
3072 }
3073 }
3074 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3075 {
3076 tree exp = SYMBOL_REF_DECL (x);
3077 if (!TREE_ASM_WRITTEN (exp))
3078 {
3079 n_deferred_constants--;
3080 output_constant_def_contents (x);
3081 }
3082 }
3083
3084 return -1;
3085 }
3086
3087 /* Look through appropriate parts of INSN, marking all entries in the
3088 constant pool which are actually being used. Entries that are only
3089 referenced by other constants are also marked as used. Emit
3090 deferred strings that are used. */
3091
3092 static void
3093 mark_constants (struct rtx_constant_pool *pool, rtx insn)
3094 {
3095 if (!INSN_P (insn))
3096 return;
3097
3098 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3099 insns, not any notes that may be attached. We don't want to mark
3100 a constant just because it happens to appear in a REG_EQUIV note. */
3101 if (GET_CODE (PATTERN (insn)) == SEQUENCE)
3102 {
3103 rtx seq = PATTERN (insn);
3104 int i, n = XVECLEN (seq, 0);
3105 for (i = 0; i < n; ++i)
3106 {
3107 rtx subinsn = XVECEXP (seq, 0, i);
3108 if (INSN_P (subinsn))
3109 for_each_rtx (&PATTERN (subinsn), mark_constant, pool);
3110 }
3111 }
3112 else
3113 for_each_rtx (&PATTERN (insn), mark_constant, pool);
3114 }
3115
3116 /* Look through the instructions for this function, and mark all the
3117 entries in POOL which are actually being used. Emit deferred constants
3118 which have indeed been used. */
3119
3120 static void
3121 mark_constant_pool (struct rtx_constant_pool *pool)
3122 {
3123 rtx insn, link;
3124
3125 if (pool->first == 0 && n_deferred_constants == 0)
3126 return;
3127
3128 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3129 mark_constants (pool, insn);
3130
3131 for (link = current_function_epilogue_delay_list;
3132 link;
3133 link = XEXP (link, 1))
3134 mark_constants (pool, XEXP (link, 0));
3135 }
3136
3137 /* Write all the constants in the constant pool. */
3138
3139 void
3140 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
3141 tree fndecl ATTRIBUTE_UNUSED)
3142 {
3143 struct rtx_constant_pool *pool = cfun->varasm->pool;
3144 struct constant_descriptor_rtx *desc;
3145
3146 /* It is possible for gcc to call force_const_mem and then to later
3147 discard the instructions which refer to the constant. In such a
3148 case we do not need to output the constant. */
3149 mark_constant_pool (pool);
3150
3151 #ifdef ASM_OUTPUT_POOL_PROLOGUE
3152 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
3153 #endif
3154
3155 for (desc = pool->first; desc ; desc = desc->next)
3156 output_constant_pool_1 (desc);
3157
3158 #ifdef ASM_OUTPUT_POOL_EPILOGUE
3159 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
3160 #endif
3161 }
3162 \f
3163 /* Determine what kind of relocations EXP may need. */
3164
3165 int
3166 compute_reloc_for_constant (tree exp)
3167 {
3168 int reloc = 0, reloc2;
3169 tree tem;
3170
3171 /* Give the front-end a chance to convert VALUE to something that
3172 looks more like a constant to the back-end. */
3173 exp = lang_hooks.expand_constant (exp);
3174
3175 switch (TREE_CODE (exp))
3176 {
3177 case ADDR_EXPR:
3178 case FDESC_EXPR:
3179 /* Go inside any operations that get_inner_reference can handle and see
3180 if what's inside is a constant: no need to do anything here for
3181 addresses of variables or functions. */
3182 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
3183 tem = TREE_OPERAND (tem, 0))
3184 ;
3185
3186 if (TREE_PUBLIC (tem))
3187 reloc |= 2;
3188 else
3189 reloc |= 1;
3190 break;
3191
3192 case PLUS_EXPR:
3193 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3194 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
3195 break;
3196
3197 case MINUS_EXPR:
3198 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3199 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
3200 /* The difference of two local labels is computable at link time. */
3201 if (reloc == 1 && reloc2 == 1)
3202 reloc = 0;
3203 else
3204 reloc |= reloc2;
3205 break;
3206
3207 case NOP_EXPR:
3208 case CONVERT_EXPR:
3209 case NON_LVALUE_EXPR:
3210 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3211 break;
3212
3213 case CONSTRUCTOR:
3214 for (tem = CONSTRUCTOR_ELTS (exp); tem; tem = TREE_CHAIN (tem))
3215 if (TREE_VALUE (tem) != 0)
3216 reloc |= compute_reloc_for_constant (TREE_VALUE (tem));
3217
3218 break;
3219
3220 default:
3221 break;
3222 }
3223 return reloc;
3224 }
3225
3226 /* Find all the constants whose addresses are referenced inside of EXP,
3227 and make sure assembler code with a label has been output for each one.
3228 Indicate whether an ADDR_EXPR has been encountered. */
3229
3230 static void
3231 output_addressed_constants (tree exp)
3232 {
3233 tree tem;
3234
3235 /* Give the front-end a chance to convert VALUE to something that
3236 looks more like a constant to the back-end. */
3237 exp = lang_hooks.expand_constant (exp);
3238
3239 switch (TREE_CODE (exp))
3240 {
3241 case ADDR_EXPR:
3242 case FDESC_EXPR:
3243 /* Go inside any operations that get_inner_reference can handle and see
3244 if what's inside is a constant: no need to do anything here for
3245 addresses of variables or functions. */
3246 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
3247 tem = TREE_OPERAND (tem, 0))
3248 ;
3249
3250 if (TREE_CODE_CLASS (TREE_CODE (tem)) == 'c'
3251 || TREE_CODE (tem) == CONSTRUCTOR)
3252 output_constant_def (tem, 0);
3253 break;
3254
3255 case PLUS_EXPR:
3256 case MINUS_EXPR:
3257 output_addressed_constants (TREE_OPERAND (exp, 1));
3258 /* Fall through. */
3259
3260 case NOP_EXPR:
3261 case CONVERT_EXPR:
3262 case NON_LVALUE_EXPR:
3263 output_addressed_constants (TREE_OPERAND (exp, 0));
3264 break;
3265
3266 case CONSTRUCTOR:
3267 for (tem = CONSTRUCTOR_ELTS (exp); tem; tem = TREE_CHAIN (tem))
3268 if (TREE_VALUE (tem) != 0)
3269 output_addressed_constants (TREE_VALUE (tem));
3270
3271 break;
3272
3273 default:
3274 break;
3275 }
3276 }
3277 \f
3278 /* Return nonzero if VALUE is a valid constant-valued expression
3279 for use in initializing a static variable; one that can be an
3280 element of a "constant" initializer.
3281
3282 Return null_pointer_node if the value is absolute;
3283 if it is relocatable, return the variable that determines the relocation.
3284 We assume that VALUE has been folded as much as possible;
3285 therefore, we do not need to check for such things as
3286 arithmetic-combinations of integers. */
3287
3288 tree
3289 initializer_constant_valid_p (tree value, tree endtype)
3290 {
3291 /* Give the front-end a chance to convert VALUE to something that
3292 looks more like a constant to the back-end. */
3293 value = lang_hooks.expand_constant (value);
3294
3295 switch (TREE_CODE (value))
3296 {
3297 case CONSTRUCTOR:
3298 if ((TREE_CODE (TREE_TYPE (value)) == UNION_TYPE
3299 || TREE_CODE (TREE_TYPE (value)) == RECORD_TYPE)
3300 && TREE_CONSTANT (value)
3301 && CONSTRUCTOR_ELTS (value))
3302 {
3303 tree elt;
3304 bool absolute = true;
3305
3306 for (elt = CONSTRUCTOR_ELTS (value); elt; elt = TREE_CHAIN (elt))
3307 {
3308 tree reloc;
3309 value = TREE_VALUE (elt);
3310 reloc = initializer_constant_valid_p (value, TREE_TYPE (value));
3311 if (!reloc)
3312 return NULL_TREE;
3313 if (reloc != null_pointer_node)
3314 absolute = false;
3315 }
3316 /* For a non-absolute relocation, there is no single
3317 variable that can be "the variable that determines the
3318 relocation." */
3319 return absolute ? null_pointer_node : error_mark_node;
3320 }
3321
3322 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
3323
3324 case INTEGER_CST:
3325 case VECTOR_CST:
3326 case REAL_CST:
3327 case STRING_CST:
3328 case COMPLEX_CST:
3329 return null_pointer_node;
3330
3331 case ADDR_EXPR:
3332 case FDESC_EXPR:
3333 return staticp (TREE_OPERAND (value, 0)) ? TREE_OPERAND (value, 0) : 0;
3334
3335 case VIEW_CONVERT_EXPR:
3336 case NON_LVALUE_EXPR:
3337 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3338
3339 case CONVERT_EXPR:
3340 case NOP_EXPR:
3341 /* Allow conversions between pointer types. */
3342 if (POINTER_TYPE_P (TREE_TYPE (value))
3343 && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3344 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3345
3346 /* Allow conversions between real types. */
3347 if (FLOAT_TYPE_P (TREE_TYPE (value))
3348 && FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3349 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3350
3351 /* Allow length-preserving conversions between integer types. */
3352 if (INTEGRAL_TYPE_P (TREE_TYPE (value))
3353 && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0)))
3354 && (TYPE_PRECISION (TREE_TYPE (value))
3355 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0)))))
3356 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3357
3358 /* Allow conversions between other integer types only if
3359 explicit value. */
3360 if (INTEGRAL_TYPE_P (TREE_TYPE (value))
3361 && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3362 {
3363 tree inner = initializer_constant_valid_p (TREE_OPERAND (value, 0),
3364 endtype);
3365 if (inner == null_pointer_node)
3366 return null_pointer_node;
3367 break;
3368 }
3369
3370 /* Allow (int) &foo provided int is as wide as a pointer. */
3371 if (INTEGRAL_TYPE_P (TREE_TYPE (value))
3372 && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0)))
3373 && (TYPE_PRECISION (TREE_TYPE (value))
3374 >= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0)))))
3375 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
3376 endtype);
3377
3378 /* Likewise conversions from int to pointers, but also allow
3379 conversions from 0. */
3380 if ((POINTER_TYPE_P (TREE_TYPE (value))
3381 || TREE_CODE (TREE_TYPE (value)) == OFFSET_TYPE)
3382 && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3383 {
3384 if (integer_zerop (TREE_OPERAND (value, 0)))
3385 return null_pointer_node;
3386 else if (TYPE_PRECISION (TREE_TYPE (value))
3387 <= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0))))
3388 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
3389 endtype);
3390 }
3391
3392 /* Allow conversions to struct or union types if the value
3393 inside is okay. */
3394 if (TREE_CODE (TREE_TYPE (value)) == RECORD_TYPE
3395 || TREE_CODE (TREE_TYPE (value)) == UNION_TYPE)
3396 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
3397 endtype);
3398 break;
3399
3400 case PLUS_EXPR:
3401 if (! INTEGRAL_TYPE_P (endtype)
3402 || TYPE_PRECISION (endtype) >= POINTER_SIZE)
3403 {
3404 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0),
3405 endtype);
3406 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1),
3407 endtype);
3408 /* If either term is absolute, use the other terms relocation. */
3409 if (valid0 == null_pointer_node)
3410 return valid1;
3411 if (valid1 == null_pointer_node)
3412 return valid0;
3413 }
3414 break;
3415
3416 case MINUS_EXPR:
3417 if (! INTEGRAL_TYPE_P (endtype)
3418 || TYPE_PRECISION (endtype) >= POINTER_SIZE)
3419 {
3420 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0),
3421 endtype);
3422 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1),
3423 endtype);
3424 /* Win if second argument is absolute. */
3425 if (valid1 == null_pointer_node)
3426 return valid0;
3427 /* Win if both arguments have the same relocation.
3428 Then the value is absolute. */
3429 if (valid0 == valid1 && valid0 != 0)
3430 return null_pointer_node;
3431
3432 /* Since GCC guarantees that string constants are unique in the
3433 generated code, a subtraction between two copies of the same
3434 constant string is absolute. */
3435 if (valid0 && TREE_CODE (valid0) == STRING_CST &&
3436 valid1 && TREE_CODE (valid1) == STRING_CST &&
3437 TREE_STRING_POINTER (valid0) == TREE_STRING_POINTER (valid1))
3438 return null_pointer_node;
3439 }
3440
3441 /* Support differences between labels. */
3442 if (INTEGRAL_TYPE_P (endtype))
3443 {
3444 tree op0, op1;
3445 op0 = TREE_OPERAND (value, 0);
3446 op1 = TREE_OPERAND (value, 1);
3447
3448 /* Like STRIP_NOPS except allow the operand mode to widen.
3449 This works around a feature of fold that simplifies
3450 (int)(p1 - p2) to ((int)p1 - (int)p2) under the theory
3451 that the narrower operation is cheaper. */
3452
3453 while (TREE_CODE (op0) == NOP_EXPR
3454 || TREE_CODE (op0) == CONVERT_EXPR
3455 || TREE_CODE (op0) == NON_LVALUE_EXPR)
3456 {
3457 tree inner = TREE_OPERAND (op0, 0);
3458 if (inner == error_mark_node
3459 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
3460 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
3461 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
3462 break;
3463 op0 = inner;
3464 }
3465
3466 while (TREE_CODE (op1) == NOP_EXPR
3467 || TREE_CODE (op1) == CONVERT_EXPR
3468 || TREE_CODE (op1) == NON_LVALUE_EXPR)
3469 {
3470 tree inner = TREE_OPERAND (op1, 0);
3471 if (inner == error_mark_node
3472 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
3473 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
3474 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
3475 break;
3476 op1 = inner;
3477 }
3478
3479 if (TREE_CODE (op0) == ADDR_EXPR
3480 && TREE_CODE (TREE_OPERAND (op0, 0)) == LABEL_DECL
3481 && TREE_CODE (op1) == ADDR_EXPR
3482 && TREE_CODE (TREE_OPERAND (op1, 0)) == LABEL_DECL)
3483 return null_pointer_node;
3484 }
3485 break;
3486
3487 default:
3488 break;
3489 }
3490
3491 return 0;
3492 }
3493 \f
3494 /* Output assembler code for constant EXP to FILE, with no label.
3495 This includes the pseudo-op such as ".int" or ".byte", and a newline.
3496 Assumes output_addressed_constants has been done on EXP already.
3497
3498 Generate exactly SIZE bytes of assembler data, padding at the end
3499 with zeros if necessary. SIZE must always be specified.
3500
3501 SIZE is important for structure constructors,
3502 since trailing members may have been omitted from the constructor.
3503 It is also important for initialization of arrays from string constants
3504 since the full length of the string constant might not be wanted.
3505 It is also needed for initialization of unions, where the initializer's
3506 type is just one member, and that may not be as long as the union.
3507
3508 There a case in which we would fail to output exactly SIZE bytes:
3509 for a structure constructor that wants to produce more than SIZE bytes.
3510 But such constructors will never be generated for any possible input.
3511
3512 ALIGN is the alignment of the data in bits. */
3513
3514 void
3515 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align)
3516 {
3517 enum tree_code code;
3518 unsigned HOST_WIDE_INT thissize;
3519
3520 /* Some front-ends use constants other than the standard language-independent
3521 varieties, but which may still be output directly. Give the front-end a
3522 chance to convert EXP to a language-independent representation. */
3523 exp = lang_hooks.expand_constant (exp);
3524
3525 if (size == 0 || flag_syntax_only)
3526 return;
3527
3528 /* Eliminate any conversions since we'll be outputting the underlying
3529 constant. */
3530 while (TREE_CODE (exp) == NOP_EXPR || TREE_CODE (exp) == CONVERT_EXPR
3531 || TREE_CODE (exp) == NON_LVALUE_EXPR
3532 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
3533 exp = TREE_OPERAND (exp, 0);
3534
3535 code = TREE_CODE (TREE_TYPE (exp));
3536 thissize = int_size_in_bytes (TREE_TYPE (exp));
3537
3538 /* Allow a constructor with no elements for any data type.
3539 This means to fill the space with zeros. */
3540 if (TREE_CODE (exp) == CONSTRUCTOR && CONSTRUCTOR_ELTS (exp) == 0)
3541 {
3542 assemble_zeros (size);
3543 return;
3544 }
3545
3546 if (TREE_CODE (exp) == FDESC_EXPR)
3547 {
3548 #ifdef ASM_OUTPUT_FDESC
3549 HOST_WIDE_INT part = tree_low_cst (TREE_OPERAND (exp, 1), 0);
3550 tree decl = TREE_OPERAND (exp, 0);
3551 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
3552 #else
3553 abort ();
3554 #endif
3555 return;
3556 }
3557
3558 /* Now output the underlying data. If we've handling the padding, return.
3559 Otherwise, break and ensure THISSIZE is the size written. */
3560 switch (code)
3561 {
3562 case CHAR_TYPE:
3563 case BOOLEAN_TYPE:
3564 case INTEGER_TYPE:
3565 case ENUMERAL_TYPE:
3566 case POINTER_TYPE:
3567 case REFERENCE_TYPE:
3568 case OFFSET_TYPE:
3569 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
3570 EXPAND_INITIALIZER),
3571 size, align, 0))
3572 error ("initializer for integer value is too complicated");
3573 break;
3574
3575 case REAL_TYPE:
3576 if (TREE_CODE (exp) != REAL_CST)
3577 error ("initializer for floating value is not a floating constant");
3578
3579 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)), align);
3580 break;
3581
3582 case COMPLEX_TYPE:
3583 output_constant (TREE_REALPART (exp), thissize / 2, align);
3584 output_constant (TREE_IMAGPART (exp), thissize / 2,
3585 min_align (align, BITS_PER_UNIT * (thissize / 2)));
3586 break;
3587
3588 case ARRAY_TYPE:
3589 case VECTOR_TYPE:
3590 if (TREE_CODE (exp) == CONSTRUCTOR)
3591 {
3592 output_constructor (exp, size, align);
3593 return;
3594 }
3595 else if (TREE_CODE (exp) == STRING_CST)
3596 {
3597 thissize = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp),
3598 size);
3599 assemble_string (TREE_STRING_POINTER (exp), thissize);
3600 }
3601 else if (TREE_CODE (exp) == VECTOR_CST)
3602 {
3603 int elt_size;
3604 tree link;
3605 unsigned int nalign;
3606 enum machine_mode inner;
3607
3608 inner = GET_MODE_INNER (TYPE_MODE (TREE_TYPE (exp)));
3609 nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
3610
3611 elt_size = GET_MODE_UNIT_SIZE (TYPE_MODE (TREE_TYPE (exp)));
3612
3613 link = TREE_VECTOR_CST_ELTS (exp);
3614 output_constant (TREE_VALUE (link), elt_size, align);
3615 while ((link = TREE_CHAIN (link)) != NULL)
3616 output_constant (TREE_VALUE (link), elt_size, nalign);
3617 }
3618 else
3619 abort ();
3620 break;
3621
3622 case RECORD_TYPE:
3623 case UNION_TYPE:
3624 if (TREE_CODE (exp) == CONSTRUCTOR)
3625 output_constructor (exp, size, align);
3626 else
3627 abort ();
3628 return;
3629
3630 case SET_TYPE:
3631 if (TREE_CODE (exp) == INTEGER_CST)
3632 assemble_integer (expand_expr (exp, NULL_RTX,
3633 VOIDmode, EXPAND_INITIALIZER),
3634 thissize, align, 1);
3635 else if (TREE_CODE (exp) == CONSTRUCTOR)
3636 {
3637 unsigned char *buffer = alloca (thissize);
3638 if (get_set_constructor_bytes (exp, buffer, thissize))
3639 abort ();
3640 assemble_string ((char *) buffer, thissize);
3641 }
3642 else
3643 error ("unknown set constructor type");
3644 return;
3645
3646 case ERROR_MARK:
3647 return;
3648
3649 default:
3650 abort ();
3651 }
3652
3653 if (size > thissize)
3654 assemble_zeros (size - thissize);
3655 }
3656
3657 \f
3658 /* Subroutine of output_constructor, used for computing the size of
3659 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
3660 type with an unspecified upper bound. */
3661
3662 static unsigned HOST_WIDE_INT
3663 array_size_for_constructor (tree val)
3664 {
3665 tree max_index, i;
3666
3667 /* This code used to attempt to handle string constants that are not
3668 arrays of single-bytes, but nothing else does, so there's no point in
3669 doing it here. */
3670 if (TREE_CODE (val) == STRING_CST)
3671 return TREE_STRING_LENGTH (val);
3672
3673 max_index = NULL_TREE;
3674 for (i = CONSTRUCTOR_ELTS (val); i; i = TREE_CHAIN (i))
3675 {
3676 tree index = TREE_PURPOSE (i);
3677
3678 if (TREE_CODE (index) == RANGE_EXPR)
3679 index = TREE_OPERAND (index, 1);
3680 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
3681 max_index = index;
3682 }
3683
3684 if (max_index == NULL_TREE)
3685 return 0;
3686
3687 /* Compute the total number of array elements. */
3688 i = size_binop (MINUS_EXPR, convert (sizetype, max_index),
3689 convert (sizetype,
3690 TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)))));
3691 i = size_binop (PLUS_EXPR, i, convert (sizetype, integer_one_node));
3692
3693 /* Multiply by the array element unit size to find number of bytes. */
3694 i = size_binop (MULT_EXPR, i, TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
3695
3696 return tree_low_cst (i, 1);
3697 }
3698
3699 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
3700 Generate at least SIZE bytes, padding if necessary. */
3701
3702 static void
3703 output_constructor (tree exp, unsigned HOST_WIDE_INT size,
3704 unsigned int align)
3705 {
3706 tree type = TREE_TYPE (exp);
3707 tree link, field = 0;
3708 tree min_index = 0;
3709 /* Number of bytes output or skipped so far.
3710 In other words, current position within the constructor. */
3711 HOST_WIDE_INT total_bytes = 0;
3712 /* Nonzero means BYTE contains part of a byte, to be output. */
3713 int byte_buffer_in_use = 0;
3714 int byte = 0;
3715
3716 if (HOST_BITS_PER_WIDE_INT < BITS_PER_UNIT)
3717 abort ();
3718
3719 if (TREE_CODE (type) == RECORD_TYPE)
3720 field = TYPE_FIELDS (type);
3721
3722 if (TREE_CODE (type) == ARRAY_TYPE
3723 && TYPE_DOMAIN (type) != 0)
3724 min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (type));
3725
3726 /* As LINK goes through the elements of the constant,
3727 FIELD goes through the structure fields, if the constant is a structure.
3728 if the constant is a union, then we override this,
3729 by getting the field from the TREE_LIST element.
3730 But the constant could also be an array. Then FIELD is zero.
3731
3732 There is always a maximum of one element in the chain LINK for unions
3733 (even if the initializer in a source program incorrectly contains
3734 more one). */
3735 for (link = CONSTRUCTOR_ELTS (exp);
3736 link;
3737 link = TREE_CHAIN (link),
3738 field = field ? TREE_CHAIN (field) : 0)
3739 {
3740 tree val = TREE_VALUE (link);
3741 tree index = 0;
3742
3743 /* The element in a union constructor specifies the proper field
3744 or index. */
3745 if ((TREE_CODE (type) == RECORD_TYPE || TREE_CODE (type) == UNION_TYPE
3746 || TREE_CODE (type) == QUAL_UNION_TYPE)
3747 && TREE_PURPOSE (link) != 0)
3748 field = TREE_PURPOSE (link);
3749
3750 else if (TREE_CODE (type) == ARRAY_TYPE)
3751 index = TREE_PURPOSE (link);
3752
3753 #ifdef ASM_COMMENT_START
3754 if (field && flag_verbose_asm)
3755 fprintf (asm_out_file, "%s %s:\n",
3756 ASM_COMMENT_START,
3757 DECL_NAME (field)
3758 ? IDENTIFIER_POINTER (DECL_NAME (field))
3759 : "<anonymous>");
3760 #endif
3761
3762 /* Eliminate the marker that makes a cast not be an lvalue. */
3763 if (val != 0)
3764 STRIP_NOPS (val);
3765
3766 if (index && TREE_CODE (index) == RANGE_EXPR)
3767 {
3768 unsigned HOST_WIDE_INT fieldsize
3769 = int_size_in_bytes (TREE_TYPE (type));
3770 HOST_WIDE_INT lo_index = tree_low_cst (TREE_OPERAND (index, 0), 0);
3771 HOST_WIDE_INT hi_index = tree_low_cst (TREE_OPERAND (index, 1), 0);
3772 HOST_WIDE_INT index;
3773 unsigned int align2 = min_align (align, fieldsize * BITS_PER_UNIT);
3774
3775 for (index = lo_index; index <= hi_index; index++)
3776 {
3777 /* Output the element's initial value. */
3778 if (val == 0)
3779 assemble_zeros (fieldsize);
3780 else
3781 output_constant (val, fieldsize, align2);
3782
3783 /* Count its size. */
3784 total_bytes += fieldsize;
3785 }
3786 }
3787 else if (field == 0 || !DECL_BIT_FIELD (field))
3788 {
3789 /* An element that is not a bit-field. */
3790
3791 unsigned HOST_WIDE_INT fieldsize;
3792 /* Since this structure is static,
3793 we know the positions are constant. */
3794 HOST_WIDE_INT pos = field ? int_byte_position (field) : 0;
3795 unsigned int align2;
3796
3797 if (index != 0)
3798 pos = (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (val)), 1)
3799 * (tree_low_cst (index, 0) - tree_low_cst (min_index, 0)));
3800
3801 /* Output any buffered-up bit-fields preceding this element. */
3802 if (byte_buffer_in_use)
3803 {
3804 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
3805 total_bytes++;
3806 byte_buffer_in_use = 0;
3807 }
3808
3809 /* Advance to offset of this element.
3810 Note no alignment needed in an array, since that is guaranteed
3811 if each element has the proper size. */
3812 if ((field != 0 || index != 0) && pos != total_bytes)
3813 {
3814 assemble_zeros (pos - total_bytes);
3815 total_bytes = pos;
3816 }
3817
3818 /* Find the alignment of this element. */
3819 align2 = min_align (align, BITS_PER_UNIT * pos);
3820
3821 /* Determine size this element should occupy. */
3822 if (field)
3823 {
3824 fieldsize = 0;
3825
3826 /* If this is an array with an unspecified upper bound,
3827 the initializer determines the size. */
3828 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
3829 but we cannot do this until the deprecated support for
3830 initializing zero-length array members is removed. */
3831 if (TREE_CODE (TREE_TYPE (field)) == ARRAY_TYPE
3832 && TYPE_DOMAIN (TREE_TYPE (field))
3833 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (field))))
3834 {
3835 fieldsize = array_size_for_constructor (val);
3836 /* Given a non-empty initialization, this field had
3837 better be last. */
3838 if (fieldsize != 0 && TREE_CHAIN (field) != NULL_TREE)
3839 abort ();
3840 }
3841 else if (DECL_SIZE_UNIT (field))
3842 {
3843 /* ??? This can't be right. If the decl size overflows
3844 a host integer we will silently emit no data. */
3845 if (host_integerp (DECL_SIZE_UNIT (field), 1))
3846 fieldsize = tree_low_cst (DECL_SIZE_UNIT (field), 1);
3847 }
3848 }
3849 else
3850 fieldsize = int_size_in_bytes (TREE_TYPE (type));
3851
3852 /* Output the element's initial value. */
3853 if (val == 0)
3854 assemble_zeros (fieldsize);
3855 else
3856 output_constant (val, fieldsize, align2);
3857
3858 /* Count its size. */
3859 total_bytes += fieldsize;
3860 }
3861 else if (val != 0 && TREE_CODE (val) != INTEGER_CST)
3862 error ("invalid initial value for member `%s'",
3863 IDENTIFIER_POINTER (DECL_NAME (field)));
3864 else
3865 {
3866 /* Element that is a bit-field. */
3867
3868 HOST_WIDE_INT next_offset = int_bit_position (field);
3869 HOST_WIDE_INT end_offset
3870 = (next_offset + tree_low_cst (DECL_SIZE (field), 1));
3871
3872 if (val == 0)
3873 val = integer_zero_node;
3874
3875 /* If this field does not start in this (or, next) byte,
3876 skip some bytes. */
3877 if (next_offset / BITS_PER_UNIT != total_bytes)
3878 {
3879 /* Output remnant of any bit field in previous bytes. */
3880 if (byte_buffer_in_use)
3881 {
3882 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
3883 total_bytes++;
3884 byte_buffer_in_use = 0;
3885 }
3886
3887 /* If still not at proper byte, advance to there. */
3888 if (next_offset / BITS_PER_UNIT != total_bytes)
3889 {
3890 assemble_zeros (next_offset / BITS_PER_UNIT - total_bytes);
3891 total_bytes = next_offset / BITS_PER_UNIT;
3892 }
3893 }
3894
3895 if (! byte_buffer_in_use)
3896 byte = 0;
3897
3898 /* We must split the element into pieces that fall within
3899 separate bytes, and combine each byte with previous or
3900 following bit-fields. */
3901
3902 /* next_offset is the offset n fbits from the beginning of
3903 the structure to the next bit of this element to be processed.
3904 end_offset is the offset of the first bit past the end of
3905 this element. */
3906 while (next_offset < end_offset)
3907 {
3908 int this_time;
3909 int shift;
3910 HOST_WIDE_INT value;
3911 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
3912 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
3913
3914 /* Advance from byte to byte
3915 within this element when necessary. */
3916 while (next_byte != total_bytes)
3917 {
3918 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
3919 total_bytes++;
3920 byte = 0;
3921 }
3922
3923 /* Number of bits we can process at once
3924 (all part of the same byte). */
3925 this_time = MIN (end_offset - next_offset,
3926 BITS_PER_UNIT - next_bit);
3927 if (BYTES_BIG_ENDIAN)
3928 {
3929 /* On big-endian machine, take the most significant bits
3930 first (of the bits that are significant)
3931 and put them into bytes from the most significant end. */
3932 shift = end_offset - next_offset - this_time;
3933
3934 /* Don't try to take a bunch of bits that cross
3935 the word boundary in the INTEGER_CST. We can
3936 only select bits from the LOW or HIGH part
3937 not from both. */
3938 if (shift < HOST_BITS_PER_WIDE_INT
3939 && shift + this_time > HOST_BITS_PER_WIDE_INT)
3940 {
3941 this_time = shift + this_time - HOST_BITS_PER_WIDE_INT;
3942 shift = HOST_BITS_PER_WIDE_INT;
3943 }
3944
3945 /* Now get the bits from the appropriate constant word. */
3946 if (shift < HOST_BITS_PER_WIDE_INT)
3947 value = TREE_INT_CST_LOW (val);
3948 else if (shift < 2 * HOST_BITS_PER_WIDE_INT)
3949 {
3950 value = TREE_INT_CST_HIGH (val);
3951 shift -= HOST_BITS_PER_WIDE_INT;
3952 }
3953 else
3954 abort ();
3955
3956 /* Get the result. This works only when:
3957 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
3958 byte |= (((value >> shift)
3959 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
3960 << (BITS_PER_UNIT - this_time - next_bit));
3961 }
3962 else
3963 {
3964 /* On little-endian machines,
3965 take first the least significant bits of the value
3966 and pack them starting at the least significant
3967 bits of the bytes. */
3968 shift = next_offset - int_bit_position (field);
3969
3970 /* Don't try to take a bunch of bits that cross
3971 the word boundary in the INTEGER_CST. We can
3972 only select bits from the LOW or HIGH part
3973 not from both. */
3974 if (shift < HOST_BITS_PER_WIDE_INT
3975 && shift + this_time > HOST_BITS_PER_WIDE_INT)
3976 this_time = (HOST_BITS_PER_WIDE_INT - shift);
3977
3978 /* Now get the bits from the appropriate constant word. */
3979 if (shift < HOST_BITS_PER_WIDE_INT)
3980 value = TREE_INT_CST_LOW (val);
3981 else if (shift < 2 * HOST_BITS_PER_WIDE_INT)
3982 {
3983 value = TREE_INT_CST_HIGH (val);
3984 shift -= HOST_BITS_PER_WIDE_INT;
3985 }
3986 else
3987 abort ();
3988
3989 /* Get the result. This works only when:
3990 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
3991 byte |= (((value >> shift)
3992 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
3993 << next_bit);
3994 }
3995
3996 next_offset += this_time;
3997 byte_buffer_in_use = 1;
3998 }
3999 }
4000 }
4001
4002 if (byte_buffer_in_use)
4003 {
4004 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4005 total_bytes++;
4006 }
4007
4008 if ((unsigned HOST_WIDE_INT)total_bytes < size)
4009 assemble_zeros (size - total_bytes);
4010 }
4011
4012 /* This TREE_LIST contains any weak symbol declarations waiting
4013 to be emitted. */
4014 static GTY(()) tree weak_decls;
4015
4016 /* Mark DECL as weak. */
4017
4018 static void
4019 mark_weak (tree decl)
4020 {
4021 DECL_WEAK (decl) = 1;
4022
4023 if (DECL_RTL_SET_P (decl)
4024 && GET_CODE (DECL_RTL (decl)) == MEM
4025 && XEXP (DECL_RTL (decl), 0)
4026 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
4027 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
4028 }
4029
4030 /* Merge weak status between NEWDECL and OLDDECL. */
4031
4032 void
4033 merge_weak (tree newdecl, tree olddecl)
4034 {
4035 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
4036 return;
4037
4038 if (DECL_WEAK (newdecl))
4039 {
4040 tree wd;
4041
4042 /* NEWDECL is weak, but OLDDECL is not. */
4043
4044 /* If we already output the OLDDECL, we're in trouble; we can't
4045 go back and make it weak. This error cannot caught in
4046 declare_weak because the NEWDECL and OLDDECL was not yet
4047 been merged; therefore, TREE_ASM_WRITTEN was not set. */
4048 if (TREE_ASM_WRITTEN (olddecl))
4049 error ("%Jweak declaration of '%D' must precede definition",
4050 newdecl, newdecl);
4051
4052 /* If we've already generated rtl referencing OLDDECL, we may
4053 have done so in a way that will not function properly with
4054 a weak symbol. */
4055 else if (TREE_USED (olddecl)
4056 && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)))
4057 warning ("%Jweak declaration of '%D' after first use results "
4058 "in unspecified behavior", newdecl, newdecl);
4059
4060 if (SUPPORTS_WEAK)
4061 {
4062 /* We put the NEWDECL on the weak_decls list at some point.
4063 Replace it with the OLDDECL. */
4064 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
4065 if (TREE_VALUE (wd) == newdecl)
4066 {
4067 TREE_VALUE (wd) = olddecl;
4068 break;
4069 }
4070 /* We may not find the entry on the list. If NEWDECL is a
4071 weak alias, then we will have already called
4072 globalize_decl to remove the entry; in that case, we do
4073 not need to do anything. */
4074 }
4075
4076 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
4077 mark_weak (olddecl);
4078 }
4079 else
4080 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
4081 weak. Just update NEWDECL to indicate that it's weak too. */
4082 mark_weak (newdecl);
4083 }
4084
4085 /* Declare DECL to be a weak symbol. */
4086
4087 void
4088 declare_weak (tree decl)
4089 {
4090 if (! TREE_PUBLIC (decl))
4091 error ("%Jweak declaration of '%D' must be public", decl, decl);
4092 else if (TREE_CODE (decl) == FUNCTION_DECL && TREE_ASM_WRITTEN (decl))
4093 error ("%Jweak declaration of '%D' must precede definition", decl, decl);
4094 else if (SUPPORTS_WEAK)
4095 {
4096 if (! DECL_WEAK (decl))
4097 weak_decls = tree_cons (NULL, decl, weak_decls);
4098 }
4099 else
4100 warning ("%Jweak declaration of '%D' not supported", decl, decl);
4101
4102 mark_weak (decl);
4103 }
4104
4105 /* Emit any pending weak declarations. */
4106
4107 void
4108 weak_finish (void)
4109 {
4110 tree t;
4111
4112 for (t = weak_decls; t; t = TREE_CHAIN (t))
4113 {
4114 tree decl = TREE_VALUE (t);
4115 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
4116 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
4117 #endif
4118
4119 if (! TREE_USED (decl))
4120 continue;
4121
4122 #ifdef ASM_WEAKEN_DECL
4123 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
4124 #else
4125 #ifdef ASM_WEAKEN_LABEL
4126 ASM_WEAKEN_LABEL (asm_out_file, name);
4127 #else
4128 #ifdef ASM_OUTPUT_WEAK_ALIAS
4129 warning ("only weak aliases are supported in this configuration");
4130 return;
4131 #endif
4132 #endif
4133 #endif
4134 }
4135 }
4136
4137 /* Emit the assembly bits to indicate that DECL is globally visible. */
4138
4139 static void
4140 globalize_decl (tree decl)
4141 {
4142 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
4143
4144 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
4145 if (DECL_WEAK (decl))
4146 {
4147 tree *p, t;
4148
4149 #ifdef ASM_WEAKEN_DECL
4150 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
4151 #else
4152 ASM_WEAKEN_LABEL (asm_out_file, name);
4153 #endif
4154
4155 /* Remove this function from the pending weak list so that
4156 we do not emit multiple .weak directives for it. */
4157 for (p = &weak_decls; (t = *p) ; )
4158 {
4159 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
4160 *p = TREE_CHAIN (t);
4161 else
4162 p = &TREE_CHAIN (t);
4163 }
4164 return;
4165 }
4166 #elif defined(ASM_MAKE_LABEL_LINKONCE)
4167 if (DECL_ONE_ONLY (decl))
4168 ASM_MAKE_LABEL_LINKONCE (asm_out_file, name);
4169 #endif
4170
4171 targetm.asm_out.globalize_label (asm_out_file, name);
4172 }
4173
4174 /* Emit an assembler directive to make the symbol for DECL an alias to
4175 the symbol for TARGET. */
4176
4177 void
4178 assemble_alias (tree decl, tree target ATTRIBUTE_UNUSED)
4179 {
4180 const char *name;
4181
4182 /* We must force creation of DECL_RTL for debug info generation, even though
4183 we don't use it here. */
4184 make_decl_rtl (decl, NULL);
4185
4186 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
4187
4188 #ifdef ASM_OUTPUT_DEF
4189 /* Make name accessible from other files, if appropriate. */
4190
4191 if (TREE_PUBLIC (decl))
4192 {
4193 globalize_decl (decl);
4194 maybe_assemble_visibility (decl);
4195 }
4196
4197 #ifdef ASM_OUTPUT_DEF_FROM_DECLS
4198 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
4199 #else
4200 ASM_OUTPUT_DEF (asm_out_file, name, IDENTIFIER_POINTER (target));
4201 #endif
4202 #else /* !ASM_OUTPUT_DEF */
4203 #if defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
4204 if (DECL_WEAK (decl))
4205 {
4206 tree *p, t;
4207 #ifdef ASM_WEAKEN_DECL
4208 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
4209 #else
4210 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
4211 #endif
4212 /* Remove this function from the pending weak list so that
4213 we do not emit multiple .weak directives for it. */
4214 for (p = &weak_decls; (t = *p) ; )
4215 if (DECL_ASSEMBLER_NAME (decl)
4216 == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
4217 *p = TREE_CHAIN (t);
4218 else
4219 p = &TREE_CHAIN (t);
4220 }
4221 else
4222 warning ("only weak aliases are supported in this configuration");
4223
4224 #else
4225 warning ("alias definitions not supported in this configuration; ignored");
4226 #endif
4227 #endif
4228
4229 TREE_USED (decl) = 1;
4230 TREE_ASM_WRITTEN (decl) = 1;
4231 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
4232 }
4233
4234 /* Emit an assembler directive to set symbol for DECL visibility to
4235 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
4236
4237 void
4238 default_assemble_visibility (tree decl, int vis)
4239 {
4240 static const char * const visibility_types[] = {
4241 NULL, "internal", "hidden", "protected"
4242 };
4243
4244 const char *name, *type;
4245
4246 name = (IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)));
4247 type = visibility_types[vis];
4248
4249 #ifdef HAVE_GAS_HIDDEN
4250 fprintf (asm_out_file, "\t.%s\t", type);
4251 assemble_name (asm_out_file, name);
4252 fprintf (asm_out_file, "\n");
4253 #else
4254 warning ("visibility attribute not supported in this configuration; ignored");
4255 #endif
4256 }
4257
4258 /* A helper function to call assemble_visibility when needed for a decl. */
4259
4260 static void
4261 maybe_assemble_visibility (tree decl)
4262 {
4263 enum symbol_visibility vis = DECL_VISIBILITY (decl);
4264
4265 if (vis != VISIBILITY_DEFAULT)
4266 targetm.asm_out.visibility (decl, vis);
4267 }
4268
4269 /* Returns 1 if the target configuration supports defining public symbols
4270 so that one of them will be chosen at link time instead of generating a
4271 multiply-defined symbol error, whether through the use of weak symbols or
4272 a target-specific mechanism for having duplicates discarded. */
4273
4274 int
4275 supports_one_only (void)
4276 {
4277 if (SUPPORTS_ONE_ONLY)
4278 return 1;
4279 return SUPPORTS_WEAK;
4280 }
4281
4282 /* Set up DECL as a public symbol that can be defined in multiple
4283 translation units without generating a linker error. */
4284
4285 void
4286 make_decl_one_only (tree decl)
4287 {
4288 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != FUNCTION_DECL)
4289 abort ();
4290
4291 TREE_PUBLIC (decl) = 1;
4292
4293 if (SUPPORTS_ONE_ONLY)
4294 {
4295 #ifdef MAKE_DECL_ONE_ONLY
4296 MAKE_DECL_ONE_ONLY (decl);
4297 #endif
4298 DECL_ONE_ONLY (decl) = 1;
4299 }
4300 else if (TREE_CODE (decl) == VAR_DECL
4301 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node))
4302 DECL_COMMON (decl) = 1;
4303 else if (SUPPORTS_WEAK)
4304 DECL_WEAK (decl) = 1;
4305 else
4306 abort ();
4307 }
4308
4309 void
4310 init_varasm_once (void)
4311 {
4312 in_named_htab = htab_create_ggc (31, in_named_entry_hash,
4313 in_named_entry_eq, NULL);
4314 const_desc_htab = htab_create_ggc (1009, const_desc_hash,
4315 const_desc_eq, NULL);
4316
4317 const_alias_set = new_alias_set ();
4318 }
4319
4320 enum tls_model
4321 decl_tls_model (tree decl)
4322 {
4323 enum tls_model kind;
4324 tree attr = lookup_attribute ("tls_model", DECL_ATTRIBUTES (decl));
4325 bool is_local;
4326
4327 if (attr)
4328 {
4329 attr = TREE_VALUE (TREE_VALUE (attr));
4330 if (TREE_CODE (attr) != STRING_CST)
4331 abort ();
4332 if (!strcmp (TREE_STRING_POINTER (attr), "local-exec"))
4333 kind = TLS_MODEL_LOCAL_EXEC;
4334 else if (!strcmp (TREE_STRING_POINTER (attr), "initial-exec"))
4335 kind = TLS_MODEL_INITIAL_EXEC;
4336 else if (!strcmp (TREE_STRING_POINTER (attr), "local-dynamic"))
4337 kind = optimize ? TLS_MODEL_LOCAL_DYNAMIC : TLS_MODEL_GLOBAL_DYNAMIC;
4338 else if (!strcmp (TREE_STRING_POINTER (attr), "global-dynamic"))
4339 kind = TLS_MODEL_GLOBAL_DYNAMIC;
4340 else
4341 abort ();
4342 return kind;
4343 }
4344
4345 is_local = targetm.binds_local_p (decl);
4346 if (!flag_pic)
4347 {
4348 if (is_local)
4349 kind = TLS_MODEL_LOCAL_EXEC;
4350 else
4351 kind = TLS_MODEL_INITIAL_EXEC;
4352 }
4353 /* Local dynamic is inefficient when we're not combining the
4354 parts of the address. */
4355 else if (optimize && is_local)
4356 kind = TLS_MODEL_LOCAL_DYNAMIC;
4357 else
4358 kind = TLS_MODEL_GLOBAL_DYNAMIC;
4359 if (kind < flag_tls_default)
4360 kind = flag_tls_default;
4361
4362 return kind;
4363 }
4364
4365 /* Select a set of attributes for section NAME based on the properties
4366 of DECL and whether or not RELOC indicates that DECL's initializer
4367 might contain runtime relocations.
4368
4369 We make the section read-only and executable for a function decl,
4370 read-only for a const data decl, and writable for a non-const data decl. */
4371
4372 unsigned int
4373 default_section_type_flags (tree decl, const char *name, int reloc)
4374 {
4375 return default_section_type_flags_1 (decl, name, reloc, flag_pic);
4376 }
4377
4378 unsigned int
4379 default_section_type_flags_1 (tree decl, const char *name, int reloc,
4380 int shlib)
4381 {
4382 unsigned int flags;
4383
4384 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
4385 flags = SECTION_CODE;
4386 else if (decl && decl_readonly_section_1 (decl, reloc, shlib))
4387 flags = 0;
4388 else if (strcmp (name, UNLIKELY_EXECUTED_TEXT_SECTION_NAME) == 0)
4389 flags = SECTION_CODE;
4390 else
4391 flags = SECTION_WRITE;
4392
4393 if (decl && DECL_ONE_ONLY (decl))
4394 flags |= SECTION_LINKONCE;
4395
4396 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl))
4397 flags |= SECTION_TLS | SECTION_WRITE;
4398
4399 if (strcmp (name, ".bss") == 0
4400 || strncmp (name, ".bss.", 5) == 0
4401 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
4402 || strcmp (name, ".sbss") == 0
4403 || strncmp (name, ".sbss.", 6) == 0
4404 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0
4405 || strcmp (name, ".tbss") == 0
4406 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
4407 flags |= SECTION_BSS;
4408
4409 if (strcmp (name, ".tdata") == 0
4410 || strcmp (name, ".tbss") == 0
4411 || strncmp (name, ".gnu.linkonce.td.", 17) == 0
4412 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
4413 flags |= SECTION_TLS;
4414
4415 /* These three sections have special ELF types. They are neither
4416 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
4417 want to print a section type (@progbits or @nobits). If someone
4418 is silly enough to emit code or TLS variables to one of these
4419 sections, then don't handle them specially. */
4420 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
4421 && (strcmp (name, ".init_array") == 0
4422 || strcmp (name, ".fini_array") == 0
4423 || strcmp (name, ".preinit_array") == 0))
4424 flags |= SECTION_NOTYPE;
4425
4426 return flags;
4427 }
4428
4429 /* Output assembly to switch to section NAME with attribute FLAGS.
4430 Four variants for common object file formats. */
4431
4432 void
4433 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
4434 unsigned int flags ATTRIBUTE_UNUSED)
4435 {
4436 /* Some object formats don't support named sections at all. The
4437 front-end should already have flagged this as an error. */
4438 abort ();
4439 }
4440
4441 void
4442 default_elf_asm_named_section (const char *name, unsigned int flags)
4443 {
4444 char flagchars[10], *f = flagchars;
4445
4446 if (! named_section_first_declaration (name))
4447 {
4448 fprintf (asm_out_file, "\t.section\t%s\n", name);
4449 return;
4450 }
4451
4452 if (!(flags & SECTION_DEBUG))
4453 *f++ = 'a';
4454 if (flags & SECTION_WRITE)
4455 *f++ = 'w';
4456 if (flags & SECTION_CODE)
4457 *f++ = 'x';
4458 if (flags & SECTION_SMALL)
4459 *f++ = 's';
4460 if (flags & SECTION_MERGE)
4461 *f++ = 'M';
4462 if (flags & SECTION_STRINGS)
4463 *f++ = 'S';
4464 if (flags & SECTION_TLS)
4465 *f++ = 'T';
4466 *f = '\0';
4467
4468 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
4469
4470 if (!(flags & SECTION_NOTYPE))
4471 {
4472 const char *type;
4473
4474 if (flags & SECTION_BSS)
4475 type = "nobits";
4476 else
4477 type = "progbits";
4478
4479 fprintf (asm_out_file, ",@%s", type);
4480
4481 if (flags & SECTION_ENTSIZE)
4482 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
4483 }
4484
4485 putc ('\n', asm_out_file);
4486 }
4487
4488 void
4489 default_coff_asm_named_section (const char *name, unsigned int flags)
4490 {
4491 char flagchars[8], *f = flagchars;
4492
4493 if (flags & SECTION_WRITE)
4494 *f++ = 'w';
4495 if (flags & SECTION_CODE)
4496 *f++ = 'x';
4497 *f = '\0';
4498
4499 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
4500 }
4501
4502 void
4503 default_pe_asm_named_section (const char *name, unsigned int flags)
4504 {
4505 default_coff_asm_named_section (name, flags);
4506
4507 if (flags & SECTION_LINKONCE)
4508 {
4509 /* Functions may have been compiled at various levels of
4510 optimization so we can't use `same_size' here.
4511 Instead, have the linker pick one. */
4512 fprintf (asm_out_file, "\t.linkonce %s\n",
4513 (flags & SECTION_CODE ? "discard" : "same_size"));
4514 }
4515 }
4516 \f
4517 /* The lame default section selector. */
4518
4519 void
4520 default_select_section (tree decl, int reloc,
4521 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
4522 {
4523 bool readonly = false;
4524
4525 if (DECL_P (decl))
4526 {
4527 if (decl_readonly_section (decl, reloc))
4528 readonly = true;
4529 }
4530 else if (TREE_CODE (decl) == CONSTRUCTOR)
4531 {
4532 if (! ((flag_pic && reloc)
4533 || !TREE_READONLY (decl)
4534 || TREE_SIDE_EFFECTS (decl)
4535 || !TREE_CONSTANT (decl)))
4536 readonly = true;
4537 }
4538 else if (TREE_CODE (decl) == STRING_CST)
4539 readonly = true;
4540 else if (! (flag_pic && reloc))
4541 readonly = true;
4542
4543 if (readonly)
4544 readonly_data_section ();
4545 else
4546 data_section ();
4547 }
4548
4549 /* A helper function for default_elf_select_section and
4550 default_elf_unique_section. Categorizes the DECL. */
4551
4552 enum section_category
4553 {
4554 SECCAT_TEXT,
4555
4556 SECCAT_RODATA,
4557 SECCAT_RODATA_MERGE_STR,
4558 SECCAT_RODATA_MERGE_STR_INIT,
4559 SECCAT_RODATA_MERGE_CONST,
4560 SECCAT_SRODATA,
4561
4562 SECCAT_DATA,
4563
4564 /* To optimize loading of shared programs, define following subsections
4565 of data section:
4566 _REL Contains data that has relocations, so they get grouped
4567 together and dynamic linker will visit fewer pages in memory.
4568 _RO Contains data that is otherwise read-only. This is useful
4569 with prelinking as most relocations won't be dynamically
4570 linked and thus stay read only.
4571 _LOCAL Marks data containing relocations only to local objects.
4572 These relocations will get fully resolved by prelinking. */
4573 SECCAT_DATA_REL,
4574 SECCAT_DATA_REL_LOCAL,
4575 SECCAT_DATA_REL_RO,
4576 SECCAT_DATA_REL_RO_LOCAL,
4577
4578 SECCAT_SDATA,
4579 SECCAT_TDATA,
4580
4581 SECCAT_BSS,
4582 SECCAT_SBSS,
4583 SECCAT_TBSS
4584 };
4585
4586 static enum section_category
4587 categorize_decl_for_section (tree, int, int);
4588
4589 static enum section_category
4590 categorize_decl_for_section (tree decl, int reloc, int shlib)
4591 {
4592 enum section_category ret;
4593
4594 if (TREE_CODE (decl) == FUNCTION_DECL)
4595 return SECCAT_TEXT;
4596 else if (TREE_CODE (decl) == STRING_CST)
4597 return SECCAT_RODATA_MERGE_STR;
4598 else if (TREE_CODE (decl) == VAR_DECL)
4599 {
4600 if (DECL_INITIAL (decl) == NULL
4601 || DECL_INITIAL (decl) == error_mark_node)
4602 ret = SECCAT_BSS;
4603 else if (! TREE_READONLY (decl)
4604 || TREE_SIDE_EFFECTS (decl)
4605 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
4606 {
4607 if (shlib && (reloc & 2))
4608 ret = SECCAT_DATA_REL;
4609 else if (shlib && reloc)
4610 ret = SECCAT_DATA_REL_LOCAL;
4611 else
4612 ret = SECCAT_DATA;
4613 }
4614 else if (shlib && (reloc & 2))
4615 ret = SECCAT_DATA_REL_RO;
4616 else if (shlib && reloc)
4617 ret = SECCAT_DATA_REL_RO_LOCAL;
4618 else if (reloc || flag_merge_constants < 2)
4619 /* C and C++ don't allow different variables to share the same
4620 location. -fmerge-all-constants allows even that (at the
4621 expense of not conforming). */
4622 ret = SECCAT_RODATA;
4623 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
4624 ret = SECCAT_RODATA_MERGE_STR_INIT;
4625 else
4626 ret = SECCAT_RODATA_MERGE_CONST;
4627 }
4628 else if (TREE_CODE (decl) == CONSTRUCTOR)
4629 {
4630 if ((shlib && reloc)
4631 || TREE_SIDE_EFFECTS (decl)
4632 || ! TREE_CONSTANT (decl))
4633 ret = SECCAT_DATA;
4634 else
4635 ret = SECCAT_RODATA;
4636 }
4637 else
4638 ret = SECCAT_RODATA;
4639
4640 /* There are no read-only thread-local sections. */
4641 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl))
4642 {
4643 if (ret == SECCAT_BSS)
4644 ret = SECCAT_TBSS;
4645 else
4646 ret = SECCAT_TDATA;
4647 }
4648
4649 /* If the target uses small data sections, select it. */
4650 else if (targetm.in_small_data_p (decl))
4651 {
4652 if (ret == SECCAT_BSS)
4653 ret = SECCAT_SBSS;
4654 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
4655 ret = SECCAT_SRODATA;
4656 else
4657 ret = SECCAT_SDATA;
4658 }
4659
4660 return ret;
4661 }
4662
4663 bool
4664 decl_readonly_section (tree decl, int reloc)
4665 {
4666 return decl_readonly_section_1 (decl, reloc, flag_pic);
4667 }
4668
4669 bool
4670 decl_readonly_section_1 (tree decl, int reloc, int shlib)
4671 {
4672 switch (categorize_decl_for_section (decl, reloc, shlib))
4673 {
4674 case SECCAT_RODATA:
4675 case SECCAT_RODATA_MERGE_STR:
4676 case SECCAT_RODATA_MERGE_STR_INIT:
4677 case SECCAT_RODATA_MERGE_CONST:
4678 case SECCAT_SRODATA:
4679 return true;
4680 break;
4681 default:
4682 return false;
4683 break;
4684 }
4685 }
4686
4687 /* Select a section based on the above categorization. */
4688
4689 void
4690 default_elf_select_section (tree decl, int reloc,
4691 unsigned HOST_WIDE_INT align)
4692 {
4693 default_elf_select_section_1 (decl, reloc, align, flag_pic);
4694 }
4695
4696 void
4697 default_elf_select_section_1 (tree decl, int reloc,
4698 unsigned HOST_WIDE_INT align, int shlib)
4699 {
4700 switch (categorize_decl_for_section (decl, reloc, shlib))
4701 {
4702 case SECCAT_TEXT:
4703 /* We're not supposed to be called on FUNCTION_DECLs. */
4704 abort ();
4705 case SECCAT_RODATA:
4706 readonly_data_section ();
4707 break;
4708 case SECCAT_RODATA_MERGE_STR:
4709 mergeable_string_section (decl, align, 0);
4710 break;
4711 case SECCAT_RODATA_MERGE_STR_INIT:
4712 mergeable_string_section (DECL_INITIAL (decl), align, 0);
4713 break;
4714 case SECCAT_RODATA_MERGE_CONST:
4715 mergeable_constant_section (DECL_MODE (decl), align, 0);
4716 break;
4717 case SECCAT_SRODATA:
4718 named_section (NULL_TREE, ".sdata2", reloc);
4719 break;
4720 case SECCAT_DATA:
4721 data_section ();
4722 break;
4723 case SECCAT_DATA_REL:
4724 named_section (NULL_TREE, ".data.rel", reloc);
4725 break;
4726 case SECCAT_DATA_REL_LOCAL:
4727 named_section (NULL_TREE, ".data.rel.local", reloc);
4728 break;
4729 case SECCAT_DATA_REL_RO:
4730 named_section (NULL_TREE, ".data.rel.ro", reloc);
4731 break;
4732 case SECCAT_DATA_REL_RO_LOCAL:
4733 named_section (NULL_TREE, ".data.rel.ro.local", reloc);
4734 break;
4735 case SECCAT_SDATA:
4736 named_section (NULL_TREE, ".sdata", reloc);
4737 break;
4738 case SECCAT_TDATA:
4739 named_section (NULL_TREE, ".tdata", reloc);
4740 break;
4741 case SECCAT_BSS:
4742 #ifdef BSS_SECTION_ASM_OP
4743 bss_section ();
4744 #else
4745 named_section (NULL_TREE, ".bss", reloc);
4746 #endif
4747 break;
4748 case SECCAT_SBSS:
4749 named_section (NULL_TREE, ".sbss", reloc);
4750 break;
4751 case SECCAT_TBSS:
4752 named_section (NULL_TREE, ".tbss", reloc);
4753 break;
4754 default:
4755 abort ();
4756 }
4757 }
4758
4759 /* Construct a unique section name based on the decl name and the
4760 categorization performed above. */
4761
4762 void
4763 default_unique_section (tree decl, int reloc)
4764 {
4765 default_unique_section_1 (decl, reloc, flag_pic);
4766 }
4767
4768 void
4769 default_unique_section_1 (tree decl, int reloc, int shlib)
4770 {
4771 bool one_only = DECL_ONE_ONLY (decl);
4772 const char *prefix, *name;
4773 size_t nlen, plen;
4774 char *string;
4775
4776 switch (categorize_decl_for_section (decl, reloc, shlib))
4777 {
4778 case SECCAT_TEXT:
4779 prefix = one_only ? ".gnu.linkonce.t." : ".text.";
4780 break;
4781 case SECCAT_RODATA:
4782 case SECCAT_RODATA_MERGE_STR:
4783 case SECCAT_RODATA_MERGE_STR_INIT:
4784 case SECCAT_RODATA_MERGE_CONST:
4785 prefix = one_only ? ".gnu.linkonce.r." : ".rodata.";
4786 break;
4787 case SECCAT_SRODATA:
4788 prefix = one_only ? ".gnu.linkonce.s2." : ".sdata2.";
4789 break;
4790 case SECCAT_DATA:
4791 case SECCAT_DATA_REL:
4792 case SECCAT_DATA_REL_LOCAL:
4793 case SECCAT_DATA_REL_RO:
4794 case SECCAT_DATA_REL_RO_LOCAL:
4795 prefix = one_only ? ".gnu.linkonce.d." : ".data.";
4796 break;
4797 case SECCAT_SDATA:
4798 prefix = one_only ? ".gnu.linkonce.s." : ".sdata.";
4799 break;
4800 case SECCAT_BSS:
4801 prefix = one_only ? ".gnu.linkonce.b." : ".bss.";
4802 break;
4803 case SECCAT_SBSS:
4804 prefix = one_only ? ".gnu.linkonce.sb." : ".sbss.";
4805 break;
4806 case SECCAT_TDATA:
4807 prefix = one_only ? ".gnu.linkonce.td." : ".tdata.";
4808 break;
4809 case SECCAT_TBSS:
4810 prefix = one_only ? ".gnu.linkonce.tb." : ".tbss.";
4811 break;
4812 default:
4813 abort ();
4814 }
4815 plen = strlen (prefix);
4816
4817 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
4818 name = targetm.strip_name_encoding (name);
4819 nlen = strlen (name);
4820
4821 string = alloca (nlen + plen + 1);
4822 memcpy (string, prefix, plen);
4823 memcpy (string + plen, name, nlen + 1);
4824
4825 DECL_SECTION_NAME (decl) = build_string (nlen + plen, string);
4826 }
4827
4828 void
4829 default_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
4830 rtx x,
4831 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
4832 {
4833 if (flag_pic)
4834 switch (GET_CODE (x))
4835 {
4836 case CONST:
4837 case SYMBOL_REF:
4838 case LABEL_REF:
4839 data_section ();
4840 return;
4841
4842 default:
4843 break;
4844 }
4845
4846 readonly_data_section ();
4847 }
4848
4849 void
4850 default_elf_select_rtx_section (enum machine_mode mode, rtx x,
4851 unsigned HOST_WIDE_INT align)
4852 {
4853 /* ??? Handle small data here somehow. */
4854
4855 if (flag_pic)
4856 switch (GET_CODE (x))
4857 {
4858 case CONST:
4859 case SYMBOL_REF:
4860 named_section (NULL_TREE, ".data.rel.ro", 3);
4861 return;
4862
4863 case LABEL_REF:
4864 named_section (NULL_TREE, ".data.rel.ro.local", 1);
4865 return;
4866
4867 default:
4868 break;
4869 }
4870
4871 mergeable_constant_section (mode, align, 0);
4872 }
4873
4874 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
4875
4876 void
4877 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
4878 {
4879 rtx symbol;
4880 int flags;
4881
4882 /* Careful not to prod global register variables. */
4883 if (GET_CODE (rtl) != MEM)
4884 return;
4885 symbol = XEXP (rtl, 0);
4886 if (GET_CODE (symbol) != SYMBOL_REF)
4887 return;
4888
4889 flags = 0;
4890 if (TREE_CODE (decl) == FUNCTION_DECL)
4891 flags |= SYMBOL_FLAG_FUNCTION;
4892 if (targetm.binds_local_p (decl))
4893 flags |= SYMBOL_FLAG_LOCAL;
4894 if (targetm.in_small_data_p (decl))
4895 flags |= SYMBOL_FLAG_SMALL;
4896 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl))
4897 flags |= decl_tls_model (decl) << SYMBOL_FLAG_TLS_SHIFT;
4898 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
4899 being PUBLIC, the thing *must* be defined in this translation unit.
4900 Prevent this buglet from being propagated into rtl code as well. */
4901 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
4902 flags |= SYMBOL_FLAG_EXTERNAL;
4903
4904 SYMBOL_REF_FLAGS (symbol) = flags;
4905 }
4906
4907 /* By default, we do nothing for encode_section_info, so we need not
4908 do anything but discard the '*' marker. */
4909
4910 const char *
4911 default_strip_name_encoding (const char *str)
4912 {
4913 return str + (*str == '*');
4914 }
4915
4916 /* Assume ELF-ish defaults, since that's pretty much the most liberal
4917 wrt cross-module name binding. */
4918
4919 bool
4920 default_binds_local_p (tree exp)
4921 {
4922 return default_binds_local_p_1 (exp, flag_shlib);
4923 }
4924
4925 bool
4926 default_binds_local_p_1 (tree exp, int shlib)
4927 {
4928 bool local_p;
4929
4930 /* A non-decl is an entry in the constant pool. */
4931 if (!DECL_P (exp))
4932 local_p = true;
4933 /* Static variables are always local. */
4934 else if (! TREE_PUBLIC (exp))
4935 local_p = true;
4936 /* A variable is local if the user tells us so. */
4937 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
4938 local_p = true;
4939 /* Otherwise, variables defined outside this object may not be local. */
4940 else if (DECL_EXTERNAL (exp))
4941 local_p = false;
4942 /* Linkonce and weak data are never local. */
4943 else if (DECL_ONE_ONLY (exp) || DECL_WEAK (exp))
4944 local_p = false;
4945 /* If PIC, then assume that any global name can be overridden by
4946 symbols resolved from other modules. */
4947 else if (shlib)
4948 local_p = false;
4949 /* Uninitialized COMMON variable may be unified with symbols
4950 resolved from other modules. */
4951 else if (DECL_COMMON (exp)
4952 && (DECL_INITIAL (exp) == NULL
4953 || DECL_INITIAL (exp) == error_mark_node))
4954 local_p = false;
4955 /* Otherwise we're left with initialized (or non-common) global data
4956 which is of necessity defined locally. */
4957 else
4958 local_p = true;
4959
4960 return local_p;
4961 }
4962
4963 /* Determine whether or not a pointer mode is valid. Assume defaults
4964 of ptr_mode or Pmode - can be overridden. */
4965 bool
4966 default_valid_pointer_mode (enum machine_mode mode)
4967 {
4968 return (mode == ptr_mode || mode == Pmode);
4969 }
4970
4971 /* Default function to output code that will globalize a label. A
4972 target must define GLOBAL_ASM_OP or provide it's own function to
4973 globalize a label. */
4974 #ifdef GLOBAL_ASM_OP
4975 void
4976 default_globalize_label (FILE * stream, const char *name)
4977 {
4978 fputs (GLOBAL_ASM_OP, stream);
4979 assemble_name (stream, name);
4980 putc ('\n', stream);
4981 }
4982 #endif /* GLOBAL_ASM_OP */
4983
4984 /* Default function to output a label for unwind information. The
4985 default is to do nothing. A target that needs nonlocal labels for
4986 unwind information must provide its own function to do this. */
4987 void
4988 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
4989 tree decl ATTRIBUTE_UNUSED,
4990 int empty ATTRIBUTE_UNUSED)
4991 {
4992 }
4993
4994 /* This is how to output an internal numbered label where PREFIX is
4995 the class of label and LABELNO is the number within the class. */
4996
4997 void
4998 default_internal_label (FILE *stream, const char *prefix,
4999 unsigned long labelno)
5000 {
5001 char *const buf = alloca (40 + strlen (prefix));
5002 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
5003 ASM_OUTPUT_LABEL (stream, buf);
5004 }
5005
5006 /* This is the default behavior at the beginning of a file. It's
5007 controlled by two other target-hook toggles. */
5008 void
5009 default_file_start (void)
5010 {
5011 if (targetm.file_start_app_off && !flag_verbose_asm)
5012 fputs (ASM_APP_OFF, asm_out_file);
5013
5014 if (targetm.file_start_file_directive)
5015 output_file_directive (asm_out_file, main_input_filename);
5016 }
5017
5018 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
5019 which emits a special section directive used to indicate whether or
5020 not this object file needs an executable stack. This is primarily
5021 a GNU extension to ELF but could be used on other targets. */
5022 void
5023 file_end_indicate_exec_stack (void)
5024 {
5025 unsigned int flags = SECTION_DEBUG;
5026 if (trampolines_created)
5027 flags |= SECTION_CODE;
5028
5029 named_section_flags (".note.GNU-stack", flags);
5030 }
5031
5032 #include "gt-varasm.h"