configure.in (HAVE_LD_PIE): Check for ld -pie.
[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 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 "c-tree.h"
47 #include "ggc.h"
48 #include "langhooks.h"
49 #include "tm_p.h"
50 #include "debug.h"
51 #include "target.h"
52
53 #ifdef XCOFF_DEBUGGING_INFO
54 #include "xcoffout.h" /* Needed for external data
55 declarations for e.g. AIX 4.x. */
56 #endif
57
58 #ifndef TRAMPOLINE_ALIGNMENT
59 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
60 #endif
61
62 #ifndef ASM_STABS_OP
63 #define ASM_STABS_OP "\t.stabs\t"
64 #endif
65
66 /* The (assembler) name of the first globally-visible object output. */
67 const char *first_global_object_name;
68 const char *weak_global_object_name;
69
70 struct addr_const;
71 struct constant_descriptor_rtx;
72 struct rtx_const;
73 struct pool_constant;
74
75 #define MAX_RTX_HASH_TABLE 61
76
77 struct varasm_status GTY(())
78 {
79 /* Hash facility for making memory-constants
80 from constant rtl-expressions. It is used on RISC machines
81 where immediate integer arguments and constant addresses are restricted
82 so that such constants must be stored in memory.
83
84 This pool of constants is reinitialized for each function
85 so each function gets its own constants-pool that comes right before
86 it. */
87 struct constant_descriptor_rtx ** GTY ((length ("MAX_RTX_HASH_TABLE")))
88 x_const_rtx_hash_table;
89 struct pool_constant ** GTY ((length ("MAX_RTX_HASH_TABLE")))
90 x_const_rtx_sym_hash_table;
91
92 /* Pointers to first and last constant in pool. */
93 struct pool_constant *x_first_pool;
94 struct pool_constant *x_last_pool;
95
96 /* Current offset in constant pool (does not include any machine-specific
97 header). */
98 HOST_WIDE_INT x_pool_offset;
99
100 /* Number of tree-constants deferred during the expansion of this
101 function. */
102 unsigned int deferred_constants;
103 };
104
105 #define const_rtx_hash_table (cfun->varasm->x_const_rtx_hash_table)
106 #define const_rtx_sym_hash_table (cfun->varasm->x_const_rtx_sym_hash_table)
107 #define first_pool (cfun->varasm->x_first_pool)
108 #define last_pool (cfun->varasm->x_last_pool)
109 #define pool_offset (cfun->varasm->x_pool_offset)
110 #define n_deferred_constants (cfun->varasm->deferred_constants)
111
112 /* Number for making the label on the next
113 constant that is stored in memory. */
114
115 static GTY(()) int const_labelno;
116
117 /* Number for making the label on the next
118 static variable internal to a function. */
119
120 static GTY(()) int var_labelno;
121
122 /* Carry information from ASM_DECLARE_OBJECT_NAME
123 to ASM_FINISH_DECLARE_OBJECT. */
124
125 int size_directive_output;
126
127 /* The last decl for which assemble_variable was called,
128 if it did ASM_DECLARE_OBJECT_NAME.
129 If the last call to assemble_variable didn't do that,
130 this holds 0. */
131
132 tree last_assemble_variable_decl;
133
134 /* RTX_UNCHANGING_P in a MEM can mean it is stored into, for initialization.
135 So giving constant the alias set for the type will allow such
136 initializations to appear to conflict with the load of the constant. We
137 avoid this by giving all constants an alias set for just constants.
138 Since there will be no stores to that alias set, nothing will ever
139 conflict with them. */
140
141 static HOST_WIDE_INT const_alias_set;
142
143 static const char *strip_reg_name PARAMS ((const char *));
144 static int contains_pointers_p PARAMS ((tree));
145 static void decode_addr_const PARAMS ((tree, struct addr_const *));
146 static hashval_t const_desc_hash PARAMS ((const void *));
147 static int const_desc_eq PARAMS ((const void *, const void *));
148 static hashval_t const_hash_1 PARAMS ((const tree));
149 static int compare_constant PARAMS ((const tree, const tree));
150 static tree copy_constant PARAMS ((tree));
151 static void output_constant_def_contents PARAMS ((rtx));
152 static void decode_rtx_const PARAMS ((enum machine_mode, rtx,
153 struct rtx_const *));
154 static unsigned int const_hash_rtx PARAMS ((enum machine_mode, rtx));
155 static int compare_constant_rtx
156 PARAMS ((enum machine_mode, rtx, struct constant_descriptor_rtx *));
157 static struct constant_descriptor_rtx * record_constant_rtx
158 PARAMS ((enum machine_mode, rtx));
159 static struct pool_constant *find_pool_constant PARAMS ((struct function *, rtx));
160 static void mark_constant_pool PARAMS ((void));
161 static void mark_constants PARAMS ((rtx));
162 static int mark_constant PARAMS ((rtx *current_rtx, void *data));
163 static int output_addressed_constants PARAMS ((tree));
164 static unsigned HOST_WIDE_INT array_size_for_constructor PARAMS ((tree));
165 static unsigned min_align PARAMS ((unsigned, unsigned));
166 static void output_constructor PARAMS ((tree, unsigned HOST_WIDE_INT,
167 unsigned int));
168 static void globalize_decl PARAMS ((tree));
169 static void maybe_assemble_visibility PARAMS ((tree));
170 static int in_named_entry_eq PARAMS ((const PTR, const PTR));
171 static hashval_t in_named_entry_hash PARAMS ((const PTR));
172 #ifdef ASM_OUTPUT_BSS
173 static void asm_output_bss PARAMS ((FILE *, tree, const char *,
174 unsigned HOST_WIDE_INT,
175 unsigned HOST_WIDE_INT));
176 #endif
177 #ifdef BSS_SECTION_ASM_OP
178 #ifdef ASM_OUTPUT_ALIGNED_BSS
179 static void asm_output_aligned_bss
180 PARAMS ((FILE *, tree, const char *,
181 unsigned HOST_WIDE_INT, int)) ATTRIBUTE_UNUSED;
182 #endif
183 #endif /* BSS_SECTION_ASM_OP */
184 static bool asm_emit_uninitialised PARAMS ((tree, const char*,
185 unsigned HOST_WIDE_INT,
186 unsigned HOST_WIDE_INT));
187 static void resolve_unique_section PARAMS ((tree, int, int));
188 static void mark_weak PARAMS ((tree));
189 \f
190 enum in_section { no_section, in_text, in_data, in_named
191 #ifdef BSS_SECTION_ASM_OP
192 , in_bss
193 #endif
194 #ifdef CTORS_SECTION_ASM_OP
195 , in_ctors
196 #endif
197 #ifdef DTORS_SECTION_ASM_OP
198 , in_dtors
199 #endif
200 #ifdef READONLY_DATA_SECTION_ASM_OP
201 , in_readonly_data
202 #endif
203 #ifdef EXTRA_SECTIONS
204 , EXTRA_SECTIONS
205 #endif
206 };
207 static GTY(()) enum in_section in_section = no_section;
208
209 /* Return a nonzero value if DECL has a section attribute. */
210 #ifndef IN_NAMED_SECTION
211 #define IN_NAMED_SECTION(DECL) \
212 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \
213 && DECL_SECTION_NAME (DECL) != NULL_TREE)
214 #endif
215
216 /* Text of section name when in_section == in_named. */
217 static GTY(()) const char *in_named_name;
218
219 /* Hash table of flags that have been used for a particular named section. */
220
221 struct in_named_entry GTY(())
222 {
223 const char *name;
224 unsigned int flags;
225 bool declared;
226 };
227
228 static GTY((param_is (struct in_named_entry))) htab_t in_named_htab;
229
230 /* Define functions like text_section for any extra sections. */
231 #ifdef EXTRA_SECTION_FUNCTIONS
232 EXTRA_SECTION_FUNCTIONS
233 #endif
234
235 /* Tell assembler to switch to text section. */
236
237 void
238 text_section ()
239 {
240 if (in_section != in_text)
241 {
242 in_section = in_text;
243 #ifdef TEXT_SECTION
244 TEXT_SECTION ();
245 #else
246 fprintf (asm_out_file, "%s\n", TEXT_SECTION_ASM_OP);
247 #endif
248 }
249 }
250
251 /* Tell assembler to switch to data section. */
252
253 void
254 data_section ()
255 {
256 if (in_section != in_data)
257 {
258 in_section = in_data;
259 if (flag_shared_data)
260 {
261 #ifdef SHARED_SECTION_ASM_OP
262 fprintf (asm_out_file, "%s\n", SHARED_SECTION_ASM_OP);
263 #else
264 fprintf (asm_out_file, "%s\n", DATA_SECTION_ASM_OP);
265 #endif
266 }
267 else
268 fprintf (asm_out_file, "%s\n", DATA_SECTION_ASM_OP);
269 }
270 }
271
272 /* Tell assembler to switch to read-only data section. This is normally
273 the text section. */
274
275 void
276 readonly_data_section ()
277 {
278 #ifdef READONLY_DATA_SECTION
279 READONLY_DATA_SECTION (); /* Note this can call data_section. */
280 #else
281 #ifdef READONLY_DATA_SECTION_ASM_OP
282 if (in_section != in_readonly_data)
283 {
284 in_section = in_readonly_data;
285 fputs (READONLY_DATA_SECTION_ASM_OP, asm_out_file);
286 fputc ('\n', asm_out_file);
287 }
288 #else
289 text_section ();
290 #endif
291 #endif
292 }
293
294 /* Determine if we're in the text section. */
295
296 int
297 in_text_section ()
298 {
299 return in_section == in_text;
300 }
301
302 /* Determine if we're in the data section. */
303
304 int
305 in_data_section ()
306 {
307 return in_section == in_data;
308 }
309
310 /* Helper routines for maintaining in_named_htab. */
311
312 static int
313 in_named_entry_eq (p1, p2)
314 const PTR p1;
315 const PTR p2;
316 {
317 const struct in_named_entry *old = p1;
318 const char *new = p2;
319
320 return strcmp (old->name, new) == 0;
321 }
322
323 static hashval_t
324 in_named_entry_hash (p)
325 const PTR p;
326 {
327 const struct in_named_entry *old = p;
328 return htab_hash_string (old->name);
329 }
330
331 /* If SECTION has been seen before as a named section, return the flags
332 that were used. Otherwise, return 0. Note, that 0 is a perfectly valid
333 set of flags for a section to have, so 0 does not mean that the section
334 has not been seen. */
335
336 unsigned int
337 get_named_section_flags (section)
338 const char *section;
339 {
340 struct in_named_entry **slot;
341
342 slot = (struct in_named_entry **)
343 htab_find_slot_with_hash (in_named_htab, section,
344 htab_hash_string (section), NO_INSERT);
345
346 return slot ? (*slot)->flags : 0;
347 }
348
349 /* Returns true if the section has been declared before. Sets internal
350 flag on this section in in_named_hash so subsequent calls on this
351 section will return false. */
352
353 bool
354 named_section_first_declaration (name)
355 const char *name;
356 {
357 struct in_named_entry **slot;
358
359 slot = (struct in_named_entry **)
360 htab_find_slot_with_hash (in_named_htab, name,
361 htab_hash_string (name), NO_INSERT);
362 if (! (*slot)->declared)
363 {
364 (*slot)->declared = true;
365 return true;
366 }
367 else
368 {
369 return false;
370 }
371 }
372
373
374 /* Record FLAGS for SECTION. If SECTION was previously recorded with a
375 different set of flags, return false. */
376
377 bool
378 set_named_section_flags (section, flags)
379 const char *section;
380 unsigned int flags;
381 {
382 struct in_named_entry **slot, *entry;
383
384 slot = (struct in_named_entry **)
385 htab_find_slot_with_hash (in_named_htab, section,
386 htab_hash_string (section), INSERT);
387 entry = *slot;
388
389 if (!entry)
390 {
391 entry = (struct in_named_entry *) ggc_alloc (sizeof (*entry));
392 *slot = entry;
393 entry->name = ggc_strdup (section);
394 entry->flags = flags;
395 entry->declared = false;
396 }
397 else if (entry->flags != flags)
398 return false;
399
400 return true;
401 }
402
403 /* Tell assembler to change to section NAME with attributes FLAGS. */
404
405 void
406 named_section_flags (name, flags)
407 const char *name;
408 unsigned int flags;
409 {
410 if (in_section != in_named || strcmp (name, in_named_name) != 0)
411 {
412 if (! set_named_section_flags (name, flags))
413 abort ();
414
415 (*targetm.asm_out.named_section) (name, flags);
416
417 if (flags & SECTION_FORGET)
418 in_section = no_section;
419 else
420 {
421 in_named_name = ggc_strdup (name);
422 in_section = in_named;
423 }
424 }
425 }
426
427 /* Tell assembler to change to section NAME for DECL.
428 If DECL is NULL, just switch to section NAME.
429 If NAME is NULL, get the name from DECL.
430 If RELOC is 1, the initializer for DECL contains relocs. */
431
432 void
433 named_section (decl, name, reloc)
434 tree decl;
435 const char *name;
436 int reloc;
437 {
438 unsigned int flags;
439
440 if (decl != NULL_TREE && !DECL_P (decl))
441 abort ();
442 if (name == NULL)
443 name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
444
445 flags = (* targetm.section_type_flags) (decl, name, reloc);
446
447 /* Sanity check user variables for flag changes. Non-user
448 section flag changes will abort in named_section_flags.
449 However, don't complain if SECTION_OVERRIDE is set.
450 We trust that the setter knows that it is safe to ignore
451 the default flags for this decl. */
452 if (decl && ! set_named_section_flags (name, flags))
453 {
454 flags = get_named_section_flags (name);
455 if ((flags & SECTION_OVERRIDE) == 0)
456 error_with_decl (decl, "%s causes a section type conflict");
457 }
458
459 named_section_flags (name, flags);
460 }
461
462 /* If required, set DECL_SECTION_NAME to a unique name. */
463
464 static void
465 resolve_unique_section (decl, reloc, flag_function_or_data_sections)
466 tree decl;
467 int reloc ATTRIBUTE_UNUSED;
468 int flag_function_or_data_sections;
469 {
470 if (DECL_SECTION_NAME (decl) == NULL_TREE
471 && targetm.have_named_sections
472 && (flag_function_or_data_sections
473 || DECL_ONE_ONLY (decl)))
474 (*targetm.asm_out.unique_section) (decl, reloc);
475 }
476
477 #ifdef BSS_SECTION_ASM_OP
478
479 /* Tell the assembler to switch to the bss section. */
480
481 void
482 bss_section ()
483 {
484 if (in_section != in_bss)
485 {
486 #ifdef SHARED_BSS_SECTION_ASM_OP
487 if (flag_shared_data)
488 fprintf (asm_out_file, "%s\n", SHARED_BSS_SECTION_ASM_OP);
489 else
490 #endif
491 fprintf (asm_out_file, "%s\n", BSS_SECTION_ASM_OP);
492
493 in_section = in_bss;
494 }
495 }
496
497 #ifdef ASM_OUTPUT_BSS
498
499 /* Utility function for ASM_OUTPUT_BSS for targets to use if
500 they don't support alignments in .bss.
501 ??? It is believed that this function will work in most cases so such
502 support is localized here. */
503
504 static void
505 asm_output_bss (file, decl, name, size, rounded)
506 FILE *file;
507 tree decl ATTRIBUTE_UNUSED;
508 const char *name;
509 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED, rounded;
510 {
511 (*targetm.asm_out.globalize_label) (file, name);
512 bss_section ();
513 #ifdef ASM_DECLARE_OBJECT_NAME
514 last_assemble_variable_decl = decl;
515 ASM_DECLARE_OBJECT_NAME (file, name, decl);
516 #else
517 /* Standard thing is just output label for the object. */
518 ASM_OUTPUT_LABEL (file, name);
519 #endif /* ASM_DECLARE_OBJECT_NAME */
520 ASM_OUTPUT_SKIP (file, rounded ? rounded : 1);
521 }
522
523 #endif
524
525 #ifdef ASM_OUTPUT_ALIGNED_BSS
526
527 /* Utility function for targets to use in implementing
528 ASM_OUTPUT_ALIGNED_BSS.
529 ??? It is believed that this function will work in most cases so such
530 support is localized here. */
531
532 static void
533 asm_output_aligned_bss (file, decl, name, size, align)
534 FILE *file;
535 tree decl ATTRIBUTE_UNUSED;
536 const char *name;
537 unsigned HOST_WIDE_INT size;
538 int align;
539 {
540 bss_section ();
541 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
542 #ifdef ASM_DECLARE_OBJECT_NAME
543 last_assemble_variable_decl = decl;
544 ASM_DECLARE_OBJECT_NAME (file, name, decl);
545 #else
546 /* Standard thing is just output label for the object. */
547 ASM_OUTPUT_LABEL (file, name);
548 #endif /* ASM_DECLARE_OBJECT_NAME */
549 ASM_OUTPUT_SKIP (file, size ? size : 1);
550 }
551
552 #endif
553
554 #endif /* BSS_SECTION_ASM_OP */
555
556 /* Switch to the section for function DECL.
557
558 If DECL is NULL_TREE, switch to the text section.
559 ??? It's not clear that we will ever be passed NULL_TREE, but it's
560 safer to handle it. */
561
562 void
563 function_section (decl)
564 tree decl;
565 {
566 if (decl != NULL_TREE
567 && DECL_SECTION_NAME (decl) != NULL_TREE)
568 named_section (decl, (char *) 0, 0);
569 else
570 text_section ();
571 }
572
573 /* Switch to section for variable DECL. RELOC is the same as the
574 argument to SELECT_SECTION. */
575
576 void
577 variable_section (decl, reloc)
578 tree decl;
579 int reloc;
580 {
581 if (IN_NAMED_SECTION (decl))
582 named_section (decl, NULL, reloc);
583 else
584 (*targetm.asm_out.select_section) (decl, reloc, DECL_ALIGN (decl));
585 }
586
587 /* Tell assembler to switch to the section for string merging. */
588
589 void
590 mergeable_string_section (decl, align, flags)
591 tree decl ATTRIBUTE_UNUSED;
592 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED;
593 unsigned int flags ATTRIBUTE_UNUSED;
594 {
595 #ifdef HAVE_GAS_SHF_MERGE
596 if (flag_merge_constants
597 && TREE_CODE (decl) == STRING_CST
598 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
599 && align <= 256
600 && TREE_STRING_LENGTH (decl) >= int_size_in_bytes (TREE_TYPE (decl)))
601 {
602 enum machine_mode mode;
603 unsigned int modesize;
604 const char *str;
605 int i, j, len, unit;
606 char name[30];
607
608 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
609 modesize = GET_MODE_BITSIZE (mode);
610 if (modesize >= 8 && modesize <= 256
611 && (modesize & (modesize - 1)) == 0)
612 {
613 if (align < modesize)
614 align = modesize;
615
616 str = TREE_STRING_POINTER (decl);
617 len = TREE_STRING_LENGTH (decl);
618 unit = GET_MODE_SIZE (mode);
619
620 /* Check for embedded NUL characters. */
621 for (i = 0; i < len; i += unit)
622 {
623 for (j = 0; j < unit; j++)
624 if (str[i + j] != '\0')
625 break;
626 if (j == unit)
627 break;
628 }
629 if (i == len - unit)
630 {
631 sprintf (name, ".rodata.str%d.%d", modesize / 8,
632 (int) (align / 8));
633 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
634 if (!i && modesize < align)
635 {
636 /* A "" string with requested alignment greater than
637 character size might cause a problem:
638 if some other string required even bigger
639 alignment than "", then linker might think the
640 "" is just part of padding after some other string
641 and not put it into the hash table initially.
642 But this means "" could have smaller alignment
643 than requested. */
644 #ifdef ASM_OUTPUT_SECTION_START
645 named_section_flags (name, flags);
646 ASM_OUTPUT_SECTION_START (asm_out_file);
647 #else
648 readonly_data_section ();
649 #endif
650 return;
651 }
652
653 named_section_flags (name, flags);
654 return;
655 }
656 }
657 }
658 #endif
659 readonly_data_section ();
660 }
661
662 /* Tell assembler to switch to the section for constant merging. */
663
664 void
665 mergeable_constant_section (mode, align, flags)
666 enum machine_mode mode ATTRIBUTE_UNUSED;
667 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED;
668 unsigned int flags ATTRIBUTE_UNUSED;
669 {
670 #ifdef HAVE_GAS_SHF_MERGE
671 unsigned int modesize = GET_MODE_BITSIZE (mode);
672
673 if (flag_merge_constants
674 && mode != VOIDmode
675 && mode != BLKmode
676 && modesize <= align
677 && align >= 8
678 && align <= 256
679 && (align & (align - 1)) == 0)
680 {
681 char name[24];
682
683 sprintf (name, ".rodata.cst%d", (int) (align / 8));
684 flags |= (align / 8) | SECTION_MERGE;
685 named_section_flags (name, flags);
686 return;
687 }
688 #endif
689 readonly_data_section ();
690 }
691 \f
692 /* Given NAME, a putative register name, discard any customary prefixes. */
693
694 static const char *
695 strip_reg_name (name)
696 const char *name;
697 {
698 #ifdef REGISTER_PREFIX
699 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
700 name += strlen (REGISTER_PREFIX);
701 #endif
702 if (name[0] == '%' || name[0] == '#')
703 name++;
704 return name;
705 }
706 \f
707 /* Decode an `asm' spec for a declaration as a register name.
708 Return the register number, or -1 if nothing specified,
709 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
710 or -3 if ASMSPEC is `cc' and is not recognized,
711 or -4 if ASMSPEC is `memory' and is not recognized.
712 Accept an exact spelling or a decimal number.
713 Prefixes such as % are optional. */
714
715 int
716 decode_reg_name (asmspec)
717 const char *asmspec;
718 {
719 if (asmspec != 0)
720 {
721 int i;
722
723 /* Get rid of confusing prefixes. */
724 asmspec = strip_reg_name (asmspec);
725
726 /* Allow a decimal number as a "register name". */
727 for (i = strlen (asmspec) - 1; i >= 0; i--)
728 if (! ISDIGIT (asmspec[i]))
729 break;
730 if (asmspec[0] != 0 && i < 0)
731 {
732 i = atoi (asmspec);
733 if (i < FIRST_PSEUDO_REGISTER && i >= 0)
734 return i;
735 else
736 return -2;
737 }
738
739 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
740 if (reg_names[i][0]
741 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
742 return i;
743
744 #ifdef ADDITIONAL_REGISTER_NAMES
745 {
746 static const struct { const char *const name; const int number; } table[]
747 = ADDITIONAL_REGISTER_NAMES;
748
749 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
750 if (! strcmp (asmspec, table[i].name))
751 return table[i].number;
752 }
753 #endif /* ADDITIONAL_REGISTER_NAMES */
754
755 if (!strcmp (asmspec, "memory"))
756 return -4;
757
758 if (!strcmp (asmspec, "cc"))
759 return -3;
760
761 return -2;
762 }
763
764 return -1;
765 }
766 \f
767 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
768 have static storage duration. In other words, it should not be an
769 automatic variable, including PARM_DECLs.
770
771 There is, however, one exception: this function handles variables
772 explicitly placed in a particular register by the user.
773
774 ASMSPEC, if not 0, is the string which the user specified as the
775 assembler symbol name.
776
777 This is never called for PARM_DECL nodes. */
778
779 void
780 make_decl_rtl (decl, asmspec)
781 tree decl;
782 const char *asmspec;
783 {
784 int top_level = (DECL_CONTEXT (decl) == NULL_TREE);
785 const char *name = 0;
786 const char *new_name = 0;
787 int reg_number;
788 rtx x;
789
790 /* Check that we are not being given an automatic variable. */
791 /* A weak alias has TREE_PUBLIC set but not the other bits. */
792 if (TREE_CODE (decl) == PARM_DECL
793 || TREE_CODE (decl) == RESULT_DECL
794 || (TREE_CODE (decl) == VAR_DECL
795 && !TREE_STATIC (decl)
796 && !TREE_PUBLIC (decl)
797 && !DECL_EXTERNAL (decl)
798 && !DECL_REGISTER (decl)))
799 abort ();
800 /* And that we were not given a type or a label. */
801 else if (TREE_CODE (decl) == TYPE_DECL
802 || TREE_CODE (decl) == LABEL_DECL)
803 abort ();
804
805 /* For a duplicate declaration, we can be called twice on the
806 same DECL node. Don't discard the RTL already made. */
807 if (DECL_RTL_SET_P (decl))
808 {
809 /* If the old RTL had the wrong mode, fix the mode. */
810 if (GET_MODE (DECL_RTL (decl)) != DECL_MODE (decl))
811 SET_DECL_RTL (decl, adjust_address_nv (DECL_RTL (decl),
812 DECL_MODE (decl), 0));
813
814 /* ??? Another way to do this would be to maintain a hashed
815 table of such critters. Instead of adding stuff to a DECL
816 to give certain attributes to it, we could use an external
817 hash map from DECL to set of attributes. */
818
819 /* Let the target reassign the RTL if it wants.
820 This is necessary, for example, when one machine specific
821 decl attribute overrides another. */
822 (* targetm.encode_section_info) (decl, DECL_RTL (decl), false);
823 return;
824 }
825
826 new_name = name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
827
828 reg_number = decode_reg_name (asmspec);
829 if (reg_number == -2)
830 {
831 /* ASMSPEC is given, and not the name of a register. Mark the
832 name with a star so assemble_name won't munge it. */
833 char *starred = alloca (strlen (asmspec) + 2);
834 starred[0] = '*';
835 strcpy (starred + 1, asmspec);
836 new_name = starred;
837 }
838
839 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
840 {
841 /* First detect errors in declaring global registers. */
842 if (reg_number == -1)
843 error_with_decl (decl, "register name not specified for `%s'");
844 else if (reg_number < 0)
845 error_with_decl (decl, "invalid register name for `%s'");
846 else if (TYPE_MODE (TREE_TYPE (decl)) == BLKmode)
847 error_with_decl (decl,
848 "data type of `%s' isn't suitable for a register");
849 else if (! HARD_REGNO_MODE_OK (reg_number, TYPE_MODE (TREE_TYPE (decl))))
850 error_with_decl (decl,
851 "register specified for `%s' isn't suitable for data type");
852 /* Now handle properly declared static register variables. */
853 else
854 {
855 int nregs;
856
857 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
858 {
859 DECL_INITIAL (decl) = 0;
860 error ("global register variable has initial value");
861 }
862 if (TREE_THIS_VOLATILE (decl))
863 warning ("volatile register variables don't work as you might wish");
864
865 /* If the user specified one of the eliminables registers here,
866 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
867 confused with that register and be eliminated. This usage is
868 somewhat suspect... */
869
870 SET_DECL_RTL (decl, gen_rtx_raw_REG (DECL_MODE (decl), reg_number));
871 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
872 REG_USERVAR_P (DECL_RTL (decl)) = 1;
873
874 if (TREE_STATIC (decl))
875 {
876 /* Make this register global, so not usable for anything
877 else. */
878 #ifdef ASM_DECLARE_REGISTER_GLOBAL
879 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
880 #endif
881 nregs = HARD_REGNO_NREGS (reg_number, DECL_MODE (decl));
882 while (nregs > 0)
883 globalize_reg (reg_number + --nregs);
884 }
885
886 /* As a register variable, it has no section. */
887 return;
888 }
889 }
890
891 /* Now handle ordinary static variables and functions (in memory).
892 Also handle vars declared register invalidly. */
893
894 if (reg_number >= 0 || reg_number == -3)
895 error_with_decl (decl,
896 "register name given for non-register variable `%s'");
897
898 /* Specifying a section attribute on a variable forces it into a
899 non-.bss section, and thus it cannot be common. */
900 if (TREE_CODE (decl) == VAR_DECL
901 && DECL_SECTION_NAME (decl) != NULL_TREE
902 && DECL_INITIAL (decl) == NULL_TREE
903 && DECL_COMMON (decl))
904 DECL_COMMON (decl) = 0;
905
906 /* Variables can't be both common and weak. */
907 if (TREE_CODE (decl) == VAR_DECL && DECL_WEAK (decl))
908 DECL_COMMON (decl) = 0;
909
910 /* Can't use just the variable's own name for a variable
911 whose scope is less than the whole file, unless it's a member
912 of a local class (which will already be unambiguous).
913 Concatenate a distinguishing number. */
914 if (!top_level && !TREE_PUBLIC (decl)
915 && ! (DECL_CONTEXT (decl) && TYPE_P (DECL_CONTEXT (decl)))
916 && asmspec == 0
917 && name == IDENTIFIER_POINTER (DECL_NAME (decl)))
918 {
919 char *label;
920
921 ASM_FORMAT_PRIVATE_NAME (label, name, var_labelno);
922 var_labelno++;
923 new_name = label;
924 }
925
926 if (name != new_name)
927 {
928 SET_DECL_ASSEMBLER_NAME (decl, get_identifier (new_name));
929 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
930 }
931
932 x = gen_rtx_SYMBOL_REF (Pmode, name);
933 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
934 SYMBOL_REF_DECL (x) = decl;
935
936 x = gen_rtx_MEM (DECL_MODE (decl), x);
937 if (TREE_CODE (decl) != FUNCTION_DECL)
938 set_mem_attributes (x, decl, 1);
939 SET_DECL_RTL (decl, x);
940
941 /* Optionally set flags or add text to the name to record information
942 such as that it is a function name.
943 If the name is changed, the macro ASM_OUTPUT_LABELREF
944 will have to know how to strip this information. */
945 (* targetm.encode_section_info) (decl, DECL_RTL (decl), true);
946 }
947
948 /* Make the rtl for variable VAR be volatile.
949 Use this only for static variables. */
950
951 void
952 make_var_volatile (var)
953 tree var;
954 {
955 if (GET_CODE (DECL_RTL (var)) != MEM)
956 abort ();
957
958 MEM_VOLATILE_P (DECL_RTL (var)) = 1;
959 }
960 \f
961 /* Output a string of literal assembler code
962 for an `asm' keyword used between functions. */
963
964 void
965 assemble_asm (string)
966 tree string;
967 {
968 app_enable ();
969
970 if (TREE_CODE (string) == ADDR_EXPR)
971 string = TREE_OPERAND (string, 0);
972
973 fprintf (asm_out_file, "\t%s\n", TREE_STRING_POINTER (string));
974 }
975
976 /* Record an element in the table of global destructors. SYMBOL is
977 a SYMBOL_REF of the function to be called; PRIORITY is a number
978 between 0 and MAX_INIT_PRIORITY. */
979
980 void
981 default_stabs_asm_out_destructor (symbol, priority)
982 rtx symbol;
983 int priority ATTRIBUTE_UNUSED;
984 {
985 /* Tell GNU LD that this is part of the static destructor set.
986 This will work for any system that uses stabs, most usefully
987 aout systems. */
988 fprintf (asm_out_file, "%s\"___DTOR_LIST__\",22,0,0,", ASM_STABS_OP);
989 assemble_name (asm_out_file, XSTR (symbol, 0));
990 fputc ('\n', asm_out_file);
991 }
992
993 void
994 default_named_section_asm_out_destructor (symbol, priority)
995 rtx symbol;
996 int priority;
997 {
998 const char *section = ".dtors";
999 char buf[16];
1000
1001 /* ??? This only works reliably with the GNU linker. */
1002 if (priority != DEFAULT_INIT_PRIORITY)
1003 {
1004 sprintf (buf, ".dtors.%.5u",
1005 /* Invert the numbering so the linker puts us in the proper
1006 order; constructors are run from right to left, and the
1007 linker sorts in increasing order. */
1008 MAX_INIT_PRIORITY - priority);
1009 section = buf;
1010 }
1011
1012 named_section_flags (section, SECTION_WRITE);
1013 assemble_align (POINTER_SIZE);
1014 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1015 }
1016
1017 #ifdef DTORS_SECTION_ASM_OP
1018 void
1019 dtors_section ()
1020 {
1021 if (in_section != in_dtors)
1022 {
1023 in_section = in_dtors;
1024 fputs (DTORS_SECTION_ASM_OP, asm_out_file);
1025 fputc ('\n', asm_out_file);
1026 }
1027 }
1028
1029 void
1030 default_dtor_section_asm_out_destructor (symbol, priority)
1031 rtx symbol;
1032 int priority ATTRIBUTE_UNUSED;
1033 {
1034 dtors_section ();
1035 assemble_align (POINTER_SIZE);
1036 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1037 }
1038 #endif
1039
1040 /* Likewise for global constructors. */
1041
1042 void
1043 default_stabs_asm_out_constructor (symbol, priority)
1044 rtx symbol;
1045 int priority ATTRIBUTE_UNUSED;
1046 {
1047 /* Tell GNU LD that this is part of the static destructor set.
1048 This will work for any system that uses stabs, most usefully
1049 aout systems. */
1050 fprintf (asm_out_file, "%s\"___CTOR_LIST__\",22,0,0,", ASM_STABS_OP);
1051 assemble_name (asm_out_file, XSTR (symbol, 0));
1052 fputc ('\n', asm_out_file);
1053 }
1054
1055 void
1056 default_named_section_asm_out_constructor (symbol, priority)
1057 rtx symbol;
1058 int priority;
1059 {
1060 const char *section = ".ctors";
1061 char buf[16];
1062
1063 /* ??? This only works reliably with the GNU linker. */
1064 if (priority != DEFAULT_INIT_PRIORITY)
1065 {
1066 sprintf (buf, ".ctors.%.5u",
1067 /* Invert the numbering so the linker puts us in the proper
1068 order; constructors are run from right to left, and the
1069 linker sorts in increasing order. */
1070 MAX_INIT_PRIORITY - priority);
1071 section = buf;
1072 }
1073
1074 named_section_flags (section, SECTION_WRITE);
1075 assemble_align (POINTER_SIZE);
1076 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1077 }
1078
1079 #ifdef CTORS_SECTION_ASM_OP
1080 void
1081 ctors_section ()
1082 {
1083 if (in_section != in_ctors)
1084 {
1085 in_section = in_ctors;
1086 fputs (CTORS_SECTION_ASM_OP, asm_out_file);
1087 fputc ('\n', asm_out_file);
1088 }
1089 }
1090
1091 void
1092 default_ctor_section_asm_out_constructor (symbol, priority)
1093 rtx symbol;
1094 int priority ATTRIBUTE_UNUSED;
1095 {
1096 ctors_section ();
1097 assemble_align (POINTER_SIZE);
1098 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1099 }
1100 #endif
1101 \f
1102 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1103 a nonzero value if the constant pool should be output before the
1104 start of the function, or a zero value if the pool should output
1105 after the end of the function. The default is to put it before the
1106 start. */
1107
1108 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1109 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1110 #endif
1111
1112 /* Output assembler code for the constant pool of a function and associated
1113 with defining the name of the function. DECL describes the function.
1114 NAME is the function's name. For the constant pool, we use the current
1115 constant pool data. */
1116
1117 void
1118 assemble_start_function (decl, fnname)
1119 tree decl;
1120 const char *fnname;
1121 {
1122 int align;
1123
1124 /* The following code does not need preprocessing in the assembler. */
1125
1126 app_disable ();
1127
1128 if (CONSTANT_POOL_BEFORE_FUNCTION)
1129 output_constant_pool (fnname, decl);
1130
1131 resolve_unique_section (decl, 0, flag_function_sections);
1132 function_section (decl);
1133
1134 /* Tell assembler to move to target machine's alignment for functions. */
1135 align = floor_log2 (FUNCTION_BOUNDARY / BITS_PER_UNIT);
1136 if (align < force_align_functions_log)
1137 align = force_align_functions_log;
1138 if (align > 0)
1139 {
1140 ASM_OUTPUT_ALIGN (asm_out_file, align);
1141 }
1142
1143 /* Handle a user-specified function alignment.
1144 Note that we still need to align to FUNCTION_BOUNDARY, as above,
1145 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1146 if (align_functions_log > align
1147 && cfun->function_frequency != FUNCTION_FREQUENCY_UNLIKELY_EXECUTED)
1148 {
1149 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1150 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1151 align_functions_log, align_functions - 1);
1152 #else
1153 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1154 #endif
1155 }
1156
1157 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1158 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1159 #endif
1160
1161 (*debug_hooks->begin_function) (decl);
1162
1163 /* Make function name accessible from other files, if appropriate. */
1164
1165 if (TREE_PUBLIC (decl))
1166 {
1167 if (! first_global_object_name)
1168 {
1169 const char *p;
1170 char *name;
1171
1172 p = (* targetm.strip_name_encoding) (fnname);
1173 name = xstrdup (p);
1174
1175 if (! DECL_WEAK (decl) && ! DECL_ONE_ONLY (decl))
1176 first_global_object_name = name;
1177 else
1178 weak_global_object_name = name;
1179 }
1180
1181 globalize_decl (decl);
1182
1183 maybe_assemble_visibility (decl);
1184 }
1185
1186 /* Do any machine/system dependent processing of the function name */
1187 #ifdef ASM_DECLARE_FUNCTION_NAME
1188 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1189 #else
1190 /* Standard thing is just output label for the function. */
1191 ASM_OUTPUT_LABEL (asm_out_file, fnname);
1192 #endif /* ASM_DECLARE_FUNCTION_NAME */
1193 }
1194
1195 /* Output assembler code associated with defining the size of the
1196 function. DECL describes the function. NAME is the function's name. */
1197
1198 void
1199 assemble_end_function (decl, fnname)
1200 tree decl;
1201 const char *fnname;
1202 {
1203 #ifdef ASM_DECLARE_FUNCTION_SIZE
1204 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1205 #endif
1206 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1207 {
1208 output_constant_pool (fnname, decl);
1209 function_section (decl); /* need to switch back */
1210 }
1211 }
1212 \f
1213 /* Assemble code to leave SIZE bytes of zeros. */
1214
1215 void
1216 assemble_zeros (size)
1217 unsigned HOST_WIDE_INT size;
1218 {
1219 /* Do no output if -fsyntax-only. */
1220 if (flag_syntax_only)
1221 return;
1222
1223 #ifdef ASM_NO_SKIP_IN_TEXT
1224 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1225 so we must output 0s explicitly in the text section. */
1226 if (ASM_NO_SKIP_IN_TEXT && in_text_section ())
1227 {
1228 unsigned HOST_WIDE_INT i;
1229 for (i = 0; i < size; i++)
1230 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1231 }
1232 else
1233 #endif
1234 if (size > 0)
1235 ASM_OUTPUT_SKIP (asm_out_file, size);
1236 }
1237
1238 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1239
1240 void
1241 assemble_align (align)
1242 int align;
1243 {
1244 if (align > BITS_PER_UNIT)
1245 {
1246 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1247 }
1248 }
1249
1250 /* Assemble a string constant with the specified C string as contents. */
1251
1252 void
1253 assemble_string (p, size)
1254 const char *p;
1255 int size;
1256 {
1257 int pos = 0;
1258 int maximum = 2000;
1259
1260 /* If the string is very long, split it up. */
1261
1262 while (pos < size)
1263 {
1264 int thissize = size - pos;
1265 if (thissize > maximum)
1266 thissize = maximum;
1267
1268 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1269
1270 pos += thissize;
1271 p += thissize;
1272 }
1273 }
1274
1275 \f
1276 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1277 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1278 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1279 #else
1280 #if defined ASM_OUTPUT_ALIGNED_LOCAL
1281 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1282 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, DECL_ALIGN (decl))
1283 #else
1284 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1285 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded)
1286 #endif
1287 #endif
1288
1289 #if defined ASM_OUTPUT_ALIGNED_BSS
1290 #define ASM_EMIT_BSS(decl, name, size, rounded) \
1291 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1292 #else
1293 #if defined ASM_OUTPUT_BSS
1294 #define ASM_EMIT_BSS(decl, name, size, rounded) \
1295 ASM_OUTPUT_BSS (asm_out_file, decl, name, size, rounded)
1296 #else
1297 #undef ASM_EMIT_BSS
1298 #endif
1299 #endif
1300
1301 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1302 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1303 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1304 #else
1305 #if defined ASM_OUTPUT_ALIGNED_COMMON
1306 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1307 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size, DECL_ALIGN (decl))
1308 #else
1309 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1310 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded)
1311 #endif
1312 #endif
1313
1314 static bool
1315 asm_emit_uninitialised (decl, name, size, rounded)
1316 tree decl;
1317 const char *name;
1318 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED;
1319 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED;
1320 {
1321 enum
1322 {
1323 asm_dest_common,
1324 asm_dest_bss,
1325 asm_dest_local
1326 }
1327 destination = asm_dest_local;
1328
1329 /* ??? We should handle .bss via select_section mechanisms rather than
1330 via special target hooks. That would eliminate this special case. */
1331 if (TREE_PUBLIC (decl))
1332 {
1333 if (!DECL_COMMON (decl))
1334 #ifdef ASM_EMIT_BSS
1335 destination = asm_dest_bss;
1336 #else
1337 return false;
1338 #endif
1339 else
1340 destination = asm_dest_common;
1341 }
1342
1343 if (destination == asm_dest_bss)
1344 globalize_decl (decl);
1345 resolve_unique_section (decl, 0, flag_data_sections);
1346
1347 if (flag_shared_data)
1348 {
1349 switch (destination)
1350 {
1351 #ifdef ASM_OUTPUT_SHARED_BSS
1352 case asm_dest_bss:
1353 ASM_OUTPUT_SHARED_BSS (asm_out_file, decl, name, size, rounded);
1354 return;
1355 #endif
1356 #ifdef ASM_OUTPUT_SHARED_COMMON
1357 case asm_dest_common:
1358 ASM_OUTPUT_SHARED_COMMON (asm_out_file, name, size, rounded);
1359 return;
1360 #endif
1361 #ifdef ASM_OUTPUT_SHARED_LOCAL
1362 case asm_dest_local:
1363 ASM_OUTPUT_SHARED_LOCAL (asm_out_file, name, size, rounded);
1364 return;
1365 #endif
1366 default:
1367 break;
1368 }
1369 }
1370
1371 switch (destination)
1372 {
1373 #ifdef ASM_EMIT_BSS
1374 case asm_dest_bss:
1375 ASM_EMIT_BSS (decl, name, size, rounded);
1376 break;
1377 #endif
1378 case asm_dest_common:
1379 ASM_EMIT_COMMON (decl, name, size, rounded);
1380 break;
1381 case asm_dest_local:
1382 ASM_EMIT_LOCAL (decl, name, size, rounded);
1383 break;
1384 default:
1385 abort ();
1386 }
1387
1388 return true;
1389 }
1390
1391 /* Assemble everything that is needed for a variable or function declaration.
1392 Not used for automatic variables, and not used for function definitions.
1393 Should not be called for variables of incomplete structure type.
1394
1395 TOP_LEVEL is nonzero if this variable has file scope.
1396 AT_END is nonzero if this is the special handling, at end of compilation,
1397 to define things that have had only tentative definitions.
1398 DONT_OUTPUT_DATA if nonzero means don't actually output the
1399 initial value (that will be done by the caller). */
1400
1401 void
1402 assemble_variable (decl, top_level, at_end, dont_output_data)
1403 tree decl;
1404 int top_level ATTRIBUTE_UNUSED;
1405 int at_end ATTRIBUTE_UNUSED;
1406 int dont_output_data;
1407 {
1408 const char *name;
1409 unsigned int align;
1410 int reloc = 0;
1411 rtx decl_rtl;
1412
1413 last_assemble_variable_decl = 0;
1414
1415 /* Normally no need to say anything here for external references,
1416 since assemble_external is called by the language-specific code
1417 when a declaration is first seen. */
1418
1419 if (DECL_EXTERNAL (decl))
1420 return;
1421
1422 /* Output no assembler code for a function declaration.
1423 Only definitions of functions output anything. */
1424
1425 if (TREE_CODE (decl) == FUNCTION_DECL)
1426 return;
1427
1428 /* Do nothing for global register variables. */
1429 if (DECL_RTL_SET_P (decl) && GET_CODE (DECL_RTL (decl)) == REG)
1430 {
1431 TREE_ASM_WRITTEN (decl) = 1;
1432 return;
1433 }
1434
1435 /* If type was incomplete when the variable was declared,
1436 see if it is complete now. */
1437
1438 if (DECL_SIZE (decl) == 0)
1439 layout_decl (decl, 0);
1440
1441 /* Still incomplete => don't allocate it; treat the tentative defn
1442 (which is what it must have been) as an `extern' reference. */
1443
1444 if (!dont_output_data && DECL_SIZE (decl) == 0)
1445 {
1446 error ("%Hstorage size of `%s' isn't known",
1447 &DECL_SOURCE_LOCATION (decl),
1448 IDENTIFIER_POINTER (DECL_NAME (decl)));
1449 TREE_ASM_WRITTEN (decl) = 1;
1450 return;
1451 }
1452
1453 /* The first declaration of a variable that comes through this function
1454 decides whether it is global (in C, has external linkage)
1455 or local (in C, has internal linkage). So do nothing more
1456 if this function has already run. */
1457
1458 if (TREE_ASM_WRITTEN (decl))
1459 return;
1460
1461 /* Make sure targetm.encode_section_info is invoked before we set
1462 ASM_WRITTEN. */
1463 decl_rtl = DECL_RTL (decl);
1464
1465 TREE_ASM_WRITTEN (decl) = 1;
1466
1467 /* Do no output if -fsyntax-only. */
1468 if (flag_syntax_only)
1469 return;
1470
1471 app_disable ();
1472
1473 if (! dont_output_data
1474 && ! host_integerp (DECL_SIZE_UNIT (decl), 1))
1475 {
1476 error_with_decl (decl, "size of variable `%s' is too large");
1477 return;
1478 }
1479
1480 name = XSTR (XEXP (decl_rtl, 0), 0);
1481 if (TREE_PUBLIC (decl) && DECL_NAME (decl)
1482 && ! first_global_object_name
1483 && ! (DECL_COMMON (decl) && (DECL_INITIAL (decl) == 0
1484 || DECL_INITIAL (decl) == error_mark_node))
1485 && ! DECL_WEAK (decl)
1486 && ! DECL_ONE_ONLY (decl))
1487 {
1488 const char *p;
1489 char *xname;
1490
1491 p = (* targetm.strip_name_encoding) (name);
1492 xname = xstrdup (p);
1493 first_global_object_name = xname;
1494 }
1495
1496 /* Compute the alignment of this data. */
1497
1498 align = DECL_ALIGN (decl);
1499
1500 /* In the case for initialing an array whose length isn't specified,
1501 where we have not yet been able to do the layout,
1502 figure out the proper alignment now. */
1503 if (dont_output_data && DECL_SIZE (decl) == 0
1504 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
1505 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
1506
1507 /* Some object file formats have a maximum alignment which they support.
1508 In particular, a.out format supports a maximum alignment of 4. */
1509 #ifndef MAX_OFILE_ALIGNMENT
1510 #define MAX_OFILE_ALIGNMENT BIGGEST_ALIGNMENT
1511 #endif
1512 if (align > MAX_OFILE_ALIGNMENT)
1513 {
1514 warning_with_decl (decl,
1515 "alignment of `%s' is greater than maximum object file alignment. Using %d",
1516 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
1517 align = MAX_OFILE_ALIGNMENT;
1518 }
1519
1520 /* On some machines, it is good to increase alignment sometimes. */
1521 if (! DECL_USER_ALIGN (decl))
1522 {
1523 #ifdef DATA_ALIGNMENT
1524 align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1525 #endif
1526 #ifdef CONSTANT_ALIGNMENT
1527 if (DECL_INITIAL (decl) != 0 && DECL_INITIAL (decl) != error_mark_node)
1528 align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
1529 #endif
1530 }
1531
1532 /* Reset the alignment in case we have made it tighter, so we can benefit
1533 from it in get_pointer_alignment. */
1534 DECL_ALIGN (decl) = align;
1535 set_mem_align (decl_rtl, align);
1536
1537 if (TREE_PUBLIC (decl))
1538 maybe_assemble_visibility (decl);
1539
1540 /* Output any data that we will need to use the address of. */
1541 if (DECL_INITIAL (decl) == error_mark_node)
1542 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1543 else if (DECL_INITIAL (decl))
1544 reloc = output_addressed_constants (DECL_INITIAL (decl));
1545 resolve_unique_section (decl, reloc, flag_data_sections);
1546
1547 /* Handle uninitialized definitions. */
1548
1549 /* If the decl has been given an explicit section name, then it
1550 isn't common, and shouldn't be handled as such. */
1551 if (DECL_SECTION_NAME (decl) || dont_output_data)
1552 ;
1553 /* We don't implement common thread-local data at present. */
1554 else if (DECL_THREAD_LOCAL (decl))
1555 {
1556 if (DECL_COMMON (decl))
1557 sorry ("thread-local COMMON data not implemented");
1558 }
1559 else if (DECL_INITIAL (decl) == 0
1560 || DECL_INITIAL (decl) == error_mark_node
1561 || (flag_zero_initialized_in_bss
1562 /* Leave constant zeroes in .rodata so they can be shared. */
1563 && !TREE_READONLY (decl)
1564 && initializer_zerop (DECL_INITIAL (decl))))
1565 {
1566 unsigned HOST_WIDE_INT size = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
1567 unsigned HOST_WIDE_INT rounded = size;
1568
1569 /* Don't allocate zero bytes of common,
1570 since that means "undefined external" in the linker. */
1571 if (size == 0)
1572 rounded = 1;
1573
1574 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1575 so that each uninitialized object starts on such a boundary. */
1576 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
1577 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1578 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1579
1580 #if !defined(ASM_OUTPUT_ALIGNED_COMMON) && !defined(ASM_OUTPUT_ALIGNED_DECL_COMMON) && !defined(ASM_OUTPUT_ALIGNED_BSS)
1581 if ((unsigned HOST_WIDE_INT) DECL_ALIGN (decl) / BITS_PER_UNIT > rounded)
1582 warning_with_decl
1583 (decl, "requested alignment for %s is greater than implemented alignment of %d",rounded);
1584 #endif
1585
1586 /* If the target cannot output uninitialized but not common global data
1587 in .bss, then we have to use .data, so fall through. */
1588 if (asm_emit_uninitialised (decl, name, size, rounded))
1589 return;
1590 }
1591
1592 /* Handle initialized definitions.
1593 Also handle uninitialized global definitions if -fno-common and the
1594 target doesn't support ASM_OUTPUT_BSS. */
1595
1596 /* First make the assembler name(s) global if appropriate. */
1597 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
1598 globalize_decl (decl);
1599
1600 /* Switch to the appropriate section. */
1601 variable_section (decl, reloc);
1602
1603 /* dbxout.c needs to know this. */
1604 if (in_text_section ())
1605 DECL_IN_TEXT_SECTION (decl) = 1;
1606
1607 /* Output the alignment of this data. */
1608 if (align > BITS_PER_UNIT)
1609 {
1610 ASM_OUTPUT_ALIGN (asm_out_file,
1611 floor_log2 (DECL_ALIGN (decl) / BITS_PER_UNIT));
1612 }
1613
1614 /* Do any machine/system dependent processing of the object. */
1615 #ifdef ASM_DECLARE_OBJECT_NAME
1616 last_assemble_variable_decl = decl;
1617 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
1618 #else
1619 /* Standard thing is just output label for the object. */
1620 ASM_OUTPUT_LABEL (asm_out_file, name);
1621 #endif /* ASM_DECLARE_OBJECT_NAME */
1622
1623 if (!dont_output_data)
1624 {
1625 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
1626 /* Output the actual data. */
1627 output_constant (DECL_INITIAL (decl),
1628 tree_low_cst (DECL_SIZE_UNIT (decl), 1),
1629 align);
1630 else
1631 /* Leave space for it. */
1632 assemble_zeros (tree_low_cst (DECL_SIZE_UNIT (decl), 1));
1633 }
1634 }
1635
1636 /* Return 1 if type TYPE contains any pointers. */
1637
1638 static int
1639 contains_pointers_p (type)
1640 tree type;
1641 {
1642 switch (TREE_CODE (type))
1643 {
1644 case POINTER_TYPE:
1645 case REFERENCE_TYPE:
1646 /* I'm not sure whether OFFSET_TYPE needs this treatment,
1647 so I'll play safe and return 1. */
1648 case OFFSET_TYPE:
1649 return 1;
1650
1651 case RECORD_TYPE:
1652 case UNION_TYPE:
1653 case QUAL_UNION_TYPE:
1654 {
1655 tree fields;
1656 /* For a type that has fields, see if the fields have pointers. */
1657 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
1658 if (TREE_CODE (fields) == FIELD_DECL
1659 && contains_pointers_p (TREE_TYPE (fields)))
1660 return 1;
1661 return 0;
1662 }
1663
1664 case ARRAY_TYPE:
1665 /* An array type contains pointers if its element type does. */
1666 return contains_pointers_p (TREE_TYPE (type));
1667
1668 default:
1669 return 0;
1670 }
1671 }
1672
1673 /* Output something to declare an external symbol to the assembler.
1674 (Most assemblers don't need this, so we normally output nothing.)
1675 Do nothing if DECL is not external. */
1676
1677 void
1678 assemble_external (decl)
1679 tree decl ATTRIBUTE_UNUSED;
1680 {
1681 /* Because most platforms do not define ASM_OUTPUT_EXTERNAL, the
1682 main body of this code is only rarely exercised. To provide some
1683 testing, on all platforms, we make sure that the ASM_OUT_FILE is
1684 open. If it's not, we should not be calling this function. */
1685 if (!asm_out_file)
1686 abort ();
1687
1688 #ifdef ASM_OUTPUT_EXTERNAL
1689 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
1690 {
1691 rtx rtl = DECL_RTL (decl);
1692
1693 if (GET_CODE (rtl) == MEM && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
1694 && ! SYMBOL_REF_USED (XEXP (rtl, 0)))
1695 {
1696 /* Some systems do require some output. */
1697 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
1698 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
1699 }
1700 }
1701 #endif
1702 }
1703
1704 /* Similar, for calling a library function FUN. */
1705
1706 void
1707 assemble_external_libcall (fun)
1708 rtx fun ATTRIBUTE_UNUSED;
1709 {
1710 #ifdef ASM_OUTPUT_EXTERNAL_LIBCALL
1711 /* Declare library function name external when first used, if nec. */
1712 if (! SYMBOL_REF_USED (fun))
1713 {
1714 SYMBOL_REF_USED (fun) = 1;
1715 ASM_OUTPUT_EXTERNAL_LIBCALL (asm_out_file, fun);
1716 }
1717 #endif
1718 }
1719
1720 /* Assemble a label named NAME. */
1721
1722 void
1723 assemble_label (name)
1724 const char *name;
1725 {
1726 ASM_OUTPUT_LABEL (asm_out_file, name);
1727 }
1728
1729 /* Output to FILE a reference to the assembler name of a C-level name NAME.
1730 If NAME starts with a *, the rest of NAME is output verbatim.
1731 Otherwise NAME is transformed in an implementation-defined way
1732 (usually by the addition of an underscore).
1733 Many macros in the tm file are defined to call this function. */
1734
1735 void
1736 assemble_name (file, name)
1737 FILE *file;
1738 const char *name;
1739 {
1740 const char *real_name;
1741 tree id;
1742
1743 real_name = (* targetm.strip_name_encoding) (name);
1744
1745 id = maybe_get_identifier (real_name);
1746 if (id)
1747 TREE_SYMBOL_REFERENCED (id) = 1;
1748
1749 if (name[0] == '*')
1750 fputs (&name[1], file);
1751 else
1752 ASM_OUTPUT_LABELREF (file, name);
1753 }
1754
1755 /* Allocate SIZE bytes writable static space with a gensym name
1756 and return an RTX to refer to its address. */
1757
1758 rtx
1759 assemble_static_space (size)
1760 unsigned HOST_WIDE_INT size;
1761 {
1762 char name[12];
1763 const char *namestring;
1764 rtx x;
1765
1766 #if 0
1767 if (flag_shared_data)
1768 data_section ();
1769 #endif
1770
1771 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
1772 ++const_labelno;
1773 namestring = ggc_strdup (name);
1774
1775 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
1776 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
1777
1778 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
1779 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
1780 BIGGEST_ALIGNMENT);
1781 #else
1782 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
1783 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
1784 #else
1785 {
1786 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1787 so that each uninitialized object starts on such a boundary. */
1788 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
1789 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
1790 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
1791 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1792 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1793 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1794 }
1795 #endif
1796 #endif
1797 return x;
1798 }
1799
1800 /* Assemble the static constant template for function entry trampolines.
1801 This is done at most once per compilation.
1802 Returns an RTX for the address of the template. */
1803
1804 #ifdef TRAMPOLINE_TEMPLATE
1805 rtx
1806 assemble_trampoline_template ()
1807 {
1808 char label[256];
1809 const char *name;
1810 int align;
1811 rtx symbol;
1812
1813 /* By default, put trampoline templates in read-only data section. */
1814
1815 #ifdef TRAMPOLINE_SECTION
1816 TRAMPOLINE_SECTION ();
1817 #else
1818 readonly_data_section ();
1819 #endif
1820
1821 /* Write the assembler code to define one. */
1822 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
1823 if (align > 0)
1824 {
1825 ASM_OUTPUT_ALIGN (asm_out_file, align);
1826 }
1827
1828 (*targetm.asm_out.internal_label) (asm_out_file, "LTRAMP", 0);
1829 TRAMPOLINE_TEMPLATE (asm_out_file);
1830
1831 /* Record the rtl to refer to it. */
1832 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
1833 name = ggc_strdup (label);
1834 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
1835 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
1836
1837 return symbol;
1838 }
1839 #endif
1840 \f
1841 /* A and B are either alignments or offsets. Return the minimum alignment
1842 that may be assumed after adding the two together. */
1843
1844 static inline unsigned
1845 min_align (a, b)
1846 unsigned int a, b;
1847 {
1848 return (a | b) & -(a | b);
1849 }
1850
1851 /* Return the assembler directive for creating a given kind of integer
1852 object. SIZE is the number of bytes in the object and ALIGNED_P
1853 indicates whether it is known to be aligned. Return NULL if the
1854 assembly dialect has no such directive.
1855
1856 The returned string should be printed at the start of a new line and
1857 be followed immediately by the object's initial value. */
1858
1859 const char *
1860 integer_asm_op (size, aligned_p)
1861 int size;
1862 int aligned_p;
1863 {
1864 struct asm_int_op *ops;
1865
1866 if (aligned_p)
1867 ops = &targetm.asm_out.aligned_op;
1868 else
1869 ops = &targetm.asm_out.unaligned_op;
1870
1871 switch (size)
1872 {
1873 case 1:
1874 return targetm.asm_out.byte_op;
1875 case 2:
1876 return ops->hi;
1877 case 4:
1878 return ops->si;
1879 case 8:
1880 return ops->di;
1881 case 16:
1882 return ops->ti;
1883 default:
1884 return NULL;
1885 }
1886 }
1887
1888 /* Use directive OP to assemble an integer object X. Print OP at the
1889 start of the line, followed immediately by the value of X. */
1890
1891 void
1892 assemble_integer_with_op (op, x)
1893 const char *op;
1894 rtx x;
1895 {
1896 fputs (op, asm_out_file);
1897 output_addr_const (asm_out_file, x);
1898 fputc ('\n', asm_out_file);
1899 }
1900
1901 /* The default implementation of the asm_out.integer target hook. */
1902
1903 bool
1904 default_assemble_integer (x, size, aligned_p)
1905 rtx x ATTRIBUTE_UNUSED;
1906 unsigned int size ATTRIBUTE_UNUSED;
1907 int aligned_p ATTRIBUTE_UNUSED;
1908 {
1909 const char *op = integer_asm_op (size, aligned_p);
1910 return op && (assemble_integer_with_op (op, x), true);
1911 }
1912
1913 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
1914 the alignment of the integer in bits. Return 1 if we were able to output
1915 the constant, otherwise 0. If FORCE is nonzero, abort if we can't output
1916 the constant. */
1917
1918 bool
1919 assemble_integer (x, size, align, force)
1920 rtx x;
1921 unsigned int size;
1922 unsigned int align;
1923 int force;
1924 {
1925 int aligned_p;
1926
1927 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
1928
1929 /* See if the target hook can handle this kind of object. */
1930 if ((*targetm.asm_out.integer) (x, size, aligned_p))
1931 return true;
1932
1933 /* If the object is a multi-byte one, try splitting it up. Split
1934 it into words it if is multi-word, otherwise split it into bytes. */
1935 if (size > 1)
1936 {
1937 enum machine_mode omode, imode;
1938 unsigned int subalign;
1939 unsigned int subsize, i;
1940
1941 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
1942 subalign = MIN (align, subsize * BITS_PER_UNIT);
1943 omode = mode_for_size (subsize * BITS_PER_UNIT, MODE_INT, 0);
1944 imode = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
1945
1946 for (i = 0; i < size; i += subsize)
1947 {
1948 rtx partial = simplify_subreg (omode, x, imode, i);
1949 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
1950 break;
1951 }
1952 if (i == size)
1953 return true;
1954
1955 /* If we've printed some of it, but not all of it, there's no going
1956 back now. */
1957 if (i > 0)
1958 abort ();
1959 }
1960
1961 if (force)
1962 abort ();
1963
1964 return false;
1965 }
1966 \f
1967 void
1968 assemble_real (d, mode, align)
1969 REAL_VALUE_TYPE d;
1970 enum machine_mode mode;
1971 unsigned int align;
1972 {
1973 long data[4];
1974 long l;
1975 unsigned int nalign = min_align (align, 32);
1976
1977 switch (BITS_PER_UNIT)
1978 {
1979 case 8:
1980 switch (mode)
1981 {
1982 case SFmode:
1983 REAL_VALUE_TO_TARGET_SINGLE (d, l);
1984 assemble_integer (GEN_INT (l), 4, align, 1);
1985 break;
1986 case DFmode:
1987 REAL_VALUE_TO_TARGET_DOUBLE (d, data);
1988 assemble_integer (GEN_INT (data[0]), 4, align, 1);
1989 assemble_integer (GEN_INT (data[1]), 4, nalign, 1);
1990 break;
1991 case XFmode:
1992 REAL_VALUE_TO_TARGET_LONG_DOUBLE (d, data);
1993 assemble_integer (GEN_INT (data[0]), 4, align, 1);
1994 assemble_integer (GEN_INT (data[1]), 4, nalign, 1);
1995 assemble_integer (GEN_INT (data[2]), 4, nalign, 1);
1996 break;
1997 case TFmode:
1998 REAL_VALUE_TO_TARGET_LONG_DOUBLE (d, data);
1999 assemble_integer (GEN_INT (data[0]), 4, align, 1);
2000 assemble_integer (GEN_INT (data[1]), 4, nalign, 1);
2001 assemble_integer (GEN_INT (data[2]), 4, nalign, 1);
2002 assemble_integer (GEN_INT (data[3]), 4, nalign, 1);
2003 break;
2004 default:
2005 abort ();
2006 }
2007 break;
2008
2009 case 16:
2010 switch (mode)
2011 {
2012 case HFmode:
2013 REAL_VALUE_TO_TARGET_SINGLE (d, l);
2014 assemble_integer (GEN_INT (l), 2, align, 1);
2015 break;
2016 case TQFmode:
2017 REAL_VALUE_TO_TARGET_DOUBLE (d, data);
2018 assemble_integer (GEN_INT (data[0]), 2, align, 1);
2019 assemble_integer (GEN_INT (data[1]), 1, nalign, 1);
2020 break;
2021 default:
2022 abort ();
2023 }
2024 break;
2025
2026 case 32:
2027 switch (mode)
2028 {
2029 case QFmode:
2030 REAL_VALUE_TO_TARGET_SINGLE (d, l);
2031 assemble_integer (GEN_INT (l), 1, align, 1);
2032 break;
2033 case HFmode:
2034 REAL_VALUE_TO_TARGET_DOUBLE (d, data);
2035 assemble_integer (GEN_INT (data[0]), 1, align, 1);
2036 assemble_integer (GEN_INT (data[1]), 1, nalign, 1);
2037 break;
2038 default:
2039 abort ();
2040 }
2041 break;
2042
2043 default:
2044 abort ();
2045 }
2046 }
2047 \f
2048 /* Given an expression EXP with a constant value,
2049 reduce it to the sum of an assembler symbol and an integer.
2050 Store them both in the structure *VALUE.
2051 Abort if EXP does not reduce. */
2052
2053 struct addr_const GTY(())
2054 {
2055 rtx base;
2056 HOST_WIDE_INT offset;
2057 };
2058
2059 static void
2060 decode_addr_const (exp, value)
2061 tree exp;
2062 struct addr_const *value;
2063 {
2064 tree target = TREE_OPERAND (exp, 0);
2065 int offset = 0;
2066 rtx x;
2067
2068 while (1)
2069 {
2070 if (TREE_CODE (target) == COMPONENT_REF
2071 && host_integerp (byte_position (TREE_OPERAND (target, 1)), 0))
2072
2073 {
2074 offset += int_byte_position (TREE_OPERAND (target, 1));
2075 target = TREE_OPERAND (target, 0);
2076 }
2077 else if (TREE_CODE (target) == ARRAY_REF
2078 || TREE_CODE (target) == ARRAY_RANGE_REF)
2079 {
2080 offset += (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (target)), 1)
2081 * tree_low_cst (TREE_OPERAND (target, 1), 0));
2082 target = TREE_OPERAND (target, 0);
2083 }
2084 else
2085 break;
2086 }
2087
2088 switch (TREE_CODE (target))
2089 {
2090 case VAR_DECL:
2091 case FUNCTION_DECL:
2092 x = DECL_RTL (target);
2093 break;
2094
2095 case LABEL_DECL:
2096 x = gen_rtx_MEM (FUNCTION_MODE,
2097 gen_rtx_LABEL_REF (VOIDmode, force_label_rtx (target)));
2098 break;
2099
2100 case REAL_CST:
2101 case STRING_CST:
2102 case COMPLEX_CST:
2103 case CONSTRUCTOR:
2104 case INTEGER_CST:
2105 x = output_constant_def (target, 1);
2106 break;
2107
2108 default:
2109 abort ();
2110 }
2111
2112 if (GET_CODE (x) != MEM)
2113 abort ();
2114 x = XEXP (x, 0);
2115
2116 value->base = x;
2117 value->offset = offset;
2118 }
2119 \f
2120 /* We do RTX_UNSPEC + XINT (blah), so nothing can go after RTX_UNSPEC. */
2121 enum kind { RTX_UNKNOWN, RTX_DOUBLE, RTX_VECTOR, RTX_INT, RTX_UNSPEC };
2122 struct rtx_const GTY(())
2123 {
2124 ENUM_BITFIELD(kind) kind : 16;
2125 ENUM_BITFIELD(machine_mode) mode : 16;
2126 union rtx_const_un {
2127 REAL_VALUE_TYPE GTY ((tag ("4"))) du;
2128 struct rtx_const_u_addr {
2129 rtx base;
2130 const char *symbol;
2131 HOST_WIDE_INT offset;
2132 } GTY ((tag ("1"))) addr;
2133 struct rtx_const_u_di {
2134 HOST_WIDE_INT high;
2135 HOST_WIDE_INT low;
2136 } GTY ((tag ("0"))) di;
2137
2138 /* The max vector size we have is 16 wide; two variants for
2139 integral and floating point vectors. */
2140 struct rtx_const_int_vec {
2141 HOST_WIDE_INT high;
2142 HOST_WIDE_INT low;
2143 } GTY ((tag ("2"))) int_vec[16];
2144
2145 REAL_VALUE_TYPE GTY ((tag ("3"))) fp_vec[8];
2146
2147 } GTY ((desc ("%1.kind >= RTX_INT"), descbits ("1"))) un;
2148 };
2149
2150 /* Uniquize all constants that appear in memory.
2151 Each constant in memory thus far output is recorded
2152 in `const_hash_table'. */
2153
2154 struct constant_descriptor_tree GTY(())
2155 {
2156 /* A MEM for the constant. */
2157 rtx rtl;
2158
2159 /* The value of the constant. */
2160 tree value;
2161 };
2162
2163 static GTY((param_is (struct constant_descriptor_tree)))
2164 htab_t const_desc_htab;
2165
2166 static struct constant_descriptor_tree * build_constant_desc PARAMS ((tree));
2167 static void maybe_output_constant_def_contents
2168 PARAMS ((struct constant_descriptor_tree *, int));
2169
2170 /* Compute a hash code for a constant expression. */
2171
2172 static hashval_t
2173 const_desc_hash (ptr)
2174 const void *ptr;
2175 {
2176 return const_hash_1 (((struct constant_descriptor_tree *)ptr)->value);
2177 }
2178
2179 static hashval_t
2180 const_hash_1 (exp)
2181 const tree exp;
2182 {
2183 const char *p;
2184 hashval_t hi;
2185 int len, i;
2186 enum tree_code code = TREE_CODE (exp);
2187
2188 /* Either set P and LEN to the address and len of something to hash and
2189 exit the switch or return a value. */
2190
2191 switch (code)
2192 {
2193 case INTEGER_CST:
2194 p = (char *) &TREE_INT_CST (exp);
2195 len = sizeof TREE_INT_CST (exp);
2196 break;
2197
2198 case REAL_CST:
2199 return real_hash (TREE_REAL_CST_PTR (exp));
2200
2201 case STRING_CST:
2202 p = TREE_STRING_POINTER (exp);
2203 len = TREE_STRING_LENGTH (exp);
2204 break;
2205 case COMPLEX_CST:
2206 return (const_hash_1 (TREE_REALPART (exp)) * 5
2207 + const_hash_1 (TREE_IMAGPART (exp)));
2208
2209 case CONSTRUCTOR:
2210 if (TREE_CODE (TREE_TYPE (exp)) == SET_TYPE)
2211 {
2212 char *tmp;
2213
2214 len = int_size_in_bytes (TREE_TYPE (exp));
2215 tmp = (char *) alloca (len);
2216 get_set_constructor_bytes (exp, (unsigned char *) tmp, len);
2217 p = tmp;
2218 break;
2219 }
2220 else
2221 {
2222 tree link;
2223
2224 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2225
2226 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link))
2227 if (TREE_VALUE (link))
2228 hi = hi * 603 + const_hash_1 (TREE_VALUE (link));
2229
2230 return hi;
2231 }
2232
2233 case ADDR_EXPR:
2234 case FDESC_EXPR:
2235 {
2236 struct addr_const value;
2237
2238 decode_addr_const (exp, &value);
2239 if (GET_CODE (value.base) == SYMBOL_REF)
2240 {
2241 /* Don't hash the address of the SYMBOL_REF;
2242 only use the offset and the symbol name. */
2243 hi = value.offset;
2244 p = XSTR (value.base, 0);
2245 for (i = 0; p[i] != 0; i++)
2246 hi = ((hi * 613) + (unsigned) (p[i]));
2247 }
2248 else if (GET_CODE (value.base) == LABEL_REF)
2249 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13;
2250 else
2251 abort ();
2252 }
2253 return hi;
2254
2255 case PLUS_EXPR:
2256 case MINUS_EXPR:
2257 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2258 + const_hash_1 (TREE_OPERAND (exp, 1)));
2259
2260 case NOP_EXPR:
2261 case CONVERT_EXPR:
2262 case NON_LVALUE_EXPR:
2263 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
2264
2265 default:
2266 /* A language specific constant. Just hash the code. */
2267 return code;
2268 }
2269
2270 /* Compute hashing function */
2271 hi = len;
2272 for (i = 0; i < len; i++)
2273 hi = ((hi * 613) + (unsigned) (p[i]));
2274
2275 return hi;
2276 }
2277
2278 /* Wrapper of compare_constant, for the htab interface. */
2279 static int
2280 const_desc_eq (p1, p2)
2281 const void *p1;
2282 const void *p2;
2283 {
2284 return compare_constant (((struct constant_descriptor_tree *)p1)->value,
2285 ((struct constant_descriptor_tree *)p2)->value);
2286 }
2287
2288 /* Compare t1 and t2, and return 1 only if they are known to result in
2289 the same bit pattern on output. */
2290
2291 static int
2292 compare_constant (t1, t2)
2293 const tree t1;
2294 const tree t2;
2295 {
2296 enum tree_code typecode;
2297
2298 if (t1 == NULL_TREE)
2299 return t2 == NULL_TREE;
2300 if (t2 == NULL_TREE)
2301 return 0;
2302
2303 if (TREE_CODE (t1) != TREE_CODE (t2))
2304 return 0;
2305
2306 switch (TREE_CODE (t1))
2307 {
2308 case INTEGER_CST:
2309 /* Integer constants are the same only if the same width of type. */
2310 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2311 return 0;
2312 return tree_int_cst_equal (t1, t2);
2313
2314 case REAL_CST:
2315 /* Real constants are the same only if the same width of type. */
2316 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2317 return 0;
2318
2319 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
2320
2321 case STRING_CST:
2322 if (flag_writable_strings)
2323 return 0;
2324
2325 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2326 return 0;
2327
2328 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
2329 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
2330 TREE_STRING_LENGTH (t1)));
2331
2332 case COMPLEX_CST:
2333 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
2334 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
2335
2336 case CONSTRUCTOR:
2337 typecode = TREE_CODE (TREE_TYPE (t1));
2338 if (typecode != TREE_CODE (TREE_TYPE (t2)))
2339 return 0;
2340
2341 if (typecode == SET_TYPE)
2342 {
2343 int len = int_size_in_bytes (TREE_TYPE (t2));
2344 unsigned char *tmp1, *tmp2;
2345
2346 if (int_size_in_bytes (TREE_TYPE (t1)) != len)
2347 return 0;
2348
2349 tmp1 = (unsigned char *) alloca (len);
2350 tmp2 = (unsigned char *) alloca (len);
2351
2352 if (get_set_constructor_bytes (t1, tmp1, len) != NULL_TREE)
2353 return 0;
2354 if (get_set_constructor_bytes (t2, tmp2, len) != NULL_TREE)
2355 return 0;
2356
2357 return memcmp (tmp1, tmp2, len) != 0;
2358 }
2359 else
2360 {
2361 tree l1, l2;
2362
2363 if (typecode == ARRAY_TYPE)
2364 {
2365 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
2366 /* For arrays, check that the sizes all match. */
2367 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
2368 || size_1 == -1
2369 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
2370 return 0;
2371 }
2372 else
2373 {
2374 /* For record and union constructors, require exact type
2375 equality. */
2376 if (TREE_TYPE (t1) != TREE_TYPE (t2))
2377 return 0;
2378 }
2379
2380 for (l1 = CONSTRUCTOR_ELTS (t1), l2 = CONSTRUCTOR_ELTS (t2);
2381 l1 && l2;
2382 l1 = TREE_CHAIN (l1), l2 = TREE_CHAIN (l2))
2383 {
2384 /* Check that each value is the same... */
2385 if (! compare_constant (TREE_VALUE (l1), TREE_VALUE (l2)))
2386 return 0;
2387 /* ... and that they apply to the same fields! */
2388 if (typecode == ARRAY_TYPE)
2389 {
2390 if (! compare_constant (TREE_PURPOSE (l1),
2391 TREE_PURPOSE (l2)))
2392 return 0;
2393 }
2394 else
2395 {
2396 if (TREE_PURPOSE (l1) != TREE_PURPOSE (l2))
2397 return 0;
2398 }
2399 }
2400
2401 return l1 == NULL_TREE && l2 == NULL_TREE;
2402 }
2403
2404 case ADDR_EXPR:
2405 case FDESC_EXPR:
2406 {
2407 struct addr_const value1, value2;
2408
2409 decode_addr_const (t1, &value1);
2410 decode_addr_const (t2, &value2);
2411 return (value1.offset == value2.offset
2412 && strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
2413 }
2414
2415 case PLUS_EXPR:
2416 case MINUS_EXPR:
2417 case RANGE_EXPR:
2418 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
2419 && compare_constant(TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
2420
2421 case NOP_EXPR:
2422 case CONVERT_EXPR:
2423 case NON_LVALUE_EXPR:
2424 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
2425
2426 default:
2427 {
2428 tree nt1, nt2;
2429 nt1 = (*lang_hooks.expand_constant) (t1);
2430 nt2 = (*lang_hooks.expand_constant) (t2);
2431 if (nt1 != t1 || nt2 != t2)
2432 return compare_constant (nt1, nt2);
2433 else
2434 return 0;
2435 }
2436 }
2437
2438 /* Should not get here. */
2439 abort ();
2440 }
2441 \f
2442 /* Make a copy of the whole tree structure for a constant. This
2443 handles the same types of nodes that compare_constant handles. */
2444
2445 static tree
2446 copy_constant (exp)
2447 tree exp;
2448 {
2449 switch (TREE_CODE (exp))
2450 {
2451 case ADDR_EXPR:
2452 /* For ADDR_EXPR, we do not want to copy the decl whose address
2453 is requested. We do want to copy constants though. */
2454 if (TREE_CODE_CLASS (TREE_CODE (TREE_OPERAND (exp, 0))) == 'c')
2455 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
2456 copy_constant (TREE_OPERAND (exp, 0)));
2457 else
2458 return copy_node (exp);
2459
2460 case INTEGER_CST:
2461 case REAL_CST:
2462 case STRING_CST:
2463 return copy_node (exp);
2464
2465 case COMPLEX_CST:
2466 return build_complex (TREE_TYPE (exp),
2467 copy_constant (TREE_REALPART (exp)),
2468 copy_constant (TREE_IMAGPART (exp)));
2469
2470 case PLUS_EXPR:
2471 case MINUS_EXPR:
2472 return build (TREE_CODE (exp), TREE_TYPE (exp),
2473 copy_constant (TREE_OPERAND (exp, 0)),
2474 copy_constant (TREE_OPERAND (exp, 1)));
2475
2476 case NOP_EXPR:
2477 case CONVERT_EXPR:
2478 case NON_LVALUE_EXPR:
2479 case VIEW_CONVERT_EXPR:
2480 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
2481 copy_constant (TREE_OPERAND (exp, 0)));
2482
2483 case CONSTRUCTOR:
2484 {
2485 tree copy = copy_node (exp);
2486 tree list = copy_list (CONSTRUCTOR_ELTS (exp));
2487 tree tail;
2488
2489 CONSTRUCTOR_ELTS (copy) = list;
2490 for (tail = list; tail; tail = TREE_CHAIN (tail))
2491 TREE_VALUE (tail) = copy_constant (TREE_VALUE (tail));
2492 if (TREE_CODE (TREE_TYPE (exp)) == SET_TYPE)
2493 for (tail = list; tail; tail = TREE_CHAIN (tail))
2494 TREE_PURPOSE (tail) = copy_constant (TREE_PURPOSE (tail));
2495
2496 return copy;
2497 }
2498
2499 default:
2500 {
2501 tree t;
2502 t = (*lang_hooks.expand_constant) (exp);
2503 if (t != exp)
2504 return copy_constant (t);
2505 else
2506 abort ();
2507 }
2508 }
2509 }
2510 \f
2511 /* Subroutine of output_constant_def:
2512 No constant equal to EXP is known to have been output.
2513 Make a constant descriptor to enter EXP in the hash table.
2514 Assign the label number and construct RTL to refer to the
2515 constant's location in memory.
2516 Caller is responsible for updating the hash table. */
2517
2518 static struct constant_descriptor_tree *
2519 build_constant_desc (exp)
2520 tree exp;
2521 {
2522 rtx symbol;
2523 rtx rtl;
2524 char label[256];
2525 int labelno;
2526 struct constant_descriptor_tree *desc;
2527
2528 desc = ggc_alloc (sizeof (*desc));
2529 desc->value = copy_constant (exp);
2530
2531 /* Create a string containing the label name, in LABEL. */
2532 labelno = const_labelno++;
2533 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
2534
2535 /* We have a symbol name; construct the SYMBOL_REF and the MEM. */
2536 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
2537 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2538 SYMBOL_REF_DECL (symbol) = desc->value;
2539 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
2540
2541 rtl = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)), symbol);
2542 set_mem_attributes (rtl, exp, 1);
2543 set_mem_alias_set (rtl, 0);
2544 set_mem_alias_set (rtl, const_alias_set);
2545
2546 /* Set flags or add text to the name to record information, such as
2547 that it is a local symbol. If the name is changed, the macro
2548 ASM_OUTPUT_LABELREF will have to know how to strip this
2549 information. This call might invalidate our local variable
2550 SYMBOL; we can't use it afterward. */
2551
2552 (*targetm.encode_section_info) (exp, rtl, true);
2553
2554 desc->rtl = rtl;
2555
2556 return desc;
2557 }
2558
2559 /* Return an rtx representing a reference to constant data in memory
2560 for the constant expression EXP.
2561
2562 If assembler code for such a constant has already been output,
2563 return an rtx to refer to it.
2564 Otherwise, output such a constant in memory
2565 and generate an rtx for it.
2566
2567 If DEFER is nonzero, this constant can be deferred and output only
2568 if referenced in the function after all optimizations.
2569
2570 The const_hash_table records which constants already have label strings. */
2571
2572 rtx
2573 output_constant_def (exp, defer)
2574 tree exp;
2575 int defer;
2576 {
2577 struct constant_descriptor_tree *desc;
2578 struct constant_descriptor_tree key;
2579 void **loc;
2580
2581 /* Look up EXP in the table of constant descriptors. If we didn't find
2582 it, create a new one. */
2583 key.value = exp;
2584 loc = htab_find_slot (const_desc_htab, &key, INSERT);
2585
2586 desc = *loc;
2587 if (desc == 0)
2588 {
2589 desc = build_constant_desc (exp);
2590 *loc = desc;
2591 }
2592
2593 maybe_output_constant_def_contents (desc, defer);
2594 return desc->rtl;
2595 }
2596
2597 /* Subroutine of output_constant_def: Decide whether or not we need to
2598 output the constant DESC now, and if so, do it. */
2599 static void
2600 maybe_output_constant_def_contents (desc, defer)
2601 struct constant_descriptor_tree *desc;
2602 int defer;
2603 {
2604 rtx symbol = XEXP (desc->rtl, 0);
2605 tree exp = desc->value;
2606
2607 if (flag_syntax_only)
2608 return;
2609
2610 if (TREE_ASM_WRITTEN (exp))
2611 /* Already output; don't do it again. */
2612 return;
2613
2614 /* The only constants that cannot safely be deferred, assuming the
2615 context allows it, are strings under flag_writable_strings. */
2616 if (defer && (TREE_CODE (exp) != STRING_CST || !flag_writable_strings))
2617 {
2618 /* Increment n_deferred_constants if it exists. It needs to be at
2619 least as large as the number of constants actually referred to
2620 by the function. If it's too small we'll stop looking too early
2621 and fail to emit constants; if it's too large we'll only look
2622 through the entire function when we could have stopped earlier. */
2623 if (cfun)
2624 n_deferred_constants++;
2625 return;
2626 }
2627
2628 output_constant_def_contents (symbol);
2629 }
2630
2631 /* We must output the constant data referred to by SYMBOL; do so. */
2632
2633 static void
2634 output_constant_def_contents (symbol)
2635 rtx symbol;
2636 {
2637 tree exp = SYMBOL_REF_DECL (symbol);
2638 const char *label = XSTR (symbol, 0);
2639
2640 /* Make sure any other constants whose addresses appear in EXP
2641 are assigned label numbers. */
2642 int reloc = output_addressed_constants (exp);
2643
2644 /* Align the location counter as required by EXP's data type. */
2645 int align = TYPE_ALIGN (TREE_TYPE (exp));
2646 #ifdef CONSTANT_ALIGNMENT
2647 align = CONSTANT_ALIGNMENT (exp, align);
2648 #endif
2649
2650 /* We are no longer deferring this constant. */
2651 TREE_ASM_WRITTEN (exp) = 1;
2652
2653 if (IN_NAMED_SECTION (exp))
2654 named_section (exp, NULL, reloc);
2655 else
2656 (*targetm.asm_out.select_section) (exp, reloc, align);
2657
2658 if (align > BITS_PER_UNIT)
2659 {
2660 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2661 }
2662
2663 /* Output the label itself. */
2664 ASM_OUTPUT_LABEL (asm_out_file, label);
2665
2666 /* Output the value of EXP. */
2667 output_constant (exp,
2668 (TREE_CODE (exp) == STRING_CST
2669 ? MAX (TREE_STRING_LENGTH (exp),
2670 int_size_in_bytes (TREE_TYPE (exp)))
2671 : int_size_in_bytes (TREE_TYPE (exp))),
2672 align);
2673
2674 }
2675
2676 /* A constant which was deferred in its original location has been
2677 inserted by the RTL inliner into a different function. The
2678 current function's deferred constant count must be incremented. */
2679 void
2680 notice_rtl_inlining_of_deferred_constant ()
2681 {
2682 n_deferred_constants++;
2683 }
2684 \f
2685 /* Used in the hash tables to avoid outputting the same constant
2686 twice. Unlike 'struct constant_descriptor_tree', RTX constants
2687 are output once per function, not once per file; there seems
2688 to be no reason for the difference. */
2689
2690 struct constant_descriptor_rtx GTY(())
2691 {
2692 /* More constant_descriptors with the same hash code. */
2693 struct constant_descriptor_rtx *next;
2694
2695 /* A MEM for the constant. */
2696 rtx rtl;
2697
2698 /* The value of the constant. */
2699 struct rtx_const value;
2700 };
2701
2702 /* Structure to represent sufficient information about a constant so that
2703 it can be output when the constant pool is output, so that function
2704 integration can be done, and to simplify handling on machines that reference
2705 constant pool as base+displacement. */
2706
2707 struct pool_constant GTY(())
2708 {
2709 struct constant_descriptor_rtx *desc;
2710 struct pool_constant *next;
2711 struct pool_constant *next_sym;
2712 rtx constant;
2713 enum machine_mode mode;
2714 int labelno;
2715 unsigned int align;
2716 HOST_WIDE_INT offset;
2717 int mark;
2718 };
2719
2720 /* Hash code for a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true.
2721 The argument is XSTR (... , 0) */
2722
2723 #define SYMHASH(LABEL) (((unsigned long) (LABEL)) % MAX_RTX_HASH_TABLE)
2724 \f
2725 /* Initialize constant pool hashing for a new function. */
2726
2727 void
2728 init_varasm_status (f)
2729 struct function *f;
2730 {
2731 struct varasm_status *p;
2732 p = (struct varasm_status *) ggc_alloc (sizeof (struct varasm_status));
2733 f->varasm = p;
2734 p->x_const_rtx_hash_table
2735 = ((struct constant_descriptor_rtx **)
2736 ggc_alloc_cleared (MAX_RTX_HASH_TABLE
2737 * sizeof (struct constant_descriptor_rtx *)));
2738 p->x_const_rtx_sym_hash_table
2739 = ((struct pool_constant **)
2740 ggc_alloc_cleared (MAX_RTX_HASH_TABLE
2741 * sizeof (struct pool_constant *)));
2742
2743 p->x_first_pool = p->x_last_pool = 0;
2744 p->x_pool_offset = 0;
2745 p->deferred_constants = 0;
2746 }
2747 \f
2748
2749 /* Express an rtx for a constant integer (perhaps symbolic)
2750 as the sum of a symbol or label plus an explicit integer.
2751 They are stored into VALUE. */
2752
2753 static void
2754 decode_rtx_const (mode, x, value)
2755 enum machine_mode mode;
2756 rtx x;
2757 struct rtx_const *value;
2758 {
2759 /* Clear the whole structure, including any gaps. */
2760 memset (value, 0, sizeof (struct rtx_const));
2761
2762 value->kind = RTX_INT; /* Most usual kind. */
2763 value->mode = mode;
2764
2765 switch (GET_CODE (x))
2766 {
2767 case CONST_DOUBLE:
2768 value->kind = RTX_DOUBLE;
2769 if (GET_MODE (x) != VOIDmode)
2770 {
2771 const REAL_VALUE_TYPE *r = CONST_DOUBLE_REAL_VALUE (x);
2772
2773 value->mode = GET_MODE (x);
2774
2775 /* Copy the REAL_VALUE_TYPE by members so that we don't
2776 copy garbage from the original structure into our
2777 carefully cleaned hashing structure. */
2778 value->un.du.class = r->class;
2779 value->un.du.sign = r->sign;
2780 switch (r->class)
2781 {
2782 case rvc_zero:
2783 case rvc_inf:
2784 break;
2785 case rvc_normal:
2786 value->un.du.exp = r->exp;
2787 /* FALLTHRU */
2788 case rvc_nan:
2789 memcpy (value->un.du.sig, r->sig, sizeof (r->sig));
2790 break;
2791 default:
2792 abort ();
2793 }
2794 }
2795 else
2796 {
2797 value->un.di.low = CONST_DOUBLE_LOW (x);
2798 value->un.di.high = CONST_DOUBLE_HIGH (x);
2799 }
2800 break;
2801
2802 case CONST_VECTOR:
2803 {
2804 int units, i;
2805
2806 units = CONST_VECTOR_NUNITS (x);
2807 value->kind = RTX_VECTOR;
2808 value->mode = mode;
2809
2810 if (GET_MODE_CLASS (mode) == MODE_VECTOR_INT)
2811 {
2812 for (i = 0; i < units; ++i)
2813 {
2814 rtx elt = CONST_VECTOR_ELT (x, i);
2815 if (GET_CODE (elt) == CONST_INT)
2816 {
2817 value->un.int_vec[i].low = INTVAL (elt);
2818 value->un.int_vec[i].high = 0;
2819 }
2820 else
2821 {
2822 value->un.int_vec[i].low = CONST_DOUBLE_LOW (elt);
2823 value->un.int_vec[i].high = CONST_DOUBLE_HIGH (elt);
2824 }
2825 }
2826 }
2827 else if (GET_MODE_CLASS (mode) == MODE_VECTOR_FLOAT)
2828 {
2829 for (i = 0; i < units; ++i)
2830 {
2831 const REAL_VALUE_TYPE *r
2832 = CONST_DOUBLE_REAL_VALUE (CONST_VECTOR_ELT (x, i));
2833 REAL_VALUE_TYPE *d = &value->un.fp_vec[i];
2834
2835 /* Copy the REAL_VALUE_TYPE by members so that we don't
2836 copy garbage from the original structure into our
2837 carefully cleaned hashing structure. */
2838 d->class = r->class;
2839 d->sign = r->sign;
2840 switch (r->class)
2841 {
2842 case rvc_zero:
2843 case rvc_inf:
2844 break;
2845 case rvc_normal:
2846 d->exp = r->exp;
2847 /* FALLTHRU */
2848 case rvc_nan:
2849 memcpy (d->sig, r->sig, sizeof (r->sig));
2850 break;
2851 default:
2852 abort ();
2853 }
2854 }
2855 }
2856 else
2857 abort ();
2858 }
2859 break;
2860
2861 case CONST_INT:
2862 value->un.addr.offset = INTVAL (x);
2863 break;
2864
2865 case SYMBOL_REF:
2866 case LABEL_REF:
2867 case PC:
2868 value->un.addr.base = x;
2869 break;
2870
2871 case CONST:
2872 x = XEXP (x, 0);
2873 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == CONST_INT)
2874 {
2875 value->un.addr.base = XEXP (x, 0);
2876 value->un.addr.offset = INTVAL (XEXP (x, 1));
2877 }
2878 else if (GET_CODE (x) == MINUS && GET_CODE (XEXP (x, 1)) == CONST_INT)
2879 {
2880 value->un.addr.base = XEXP (x, 0);
2881 value->un.addr.offset = - INTVAL (XEXP (x, 1));
2882 }
2883 else
2884 {
2885 value->un.addr.base = x;
2886 value->un.addr.offset = 0;
2887 }
2888 break;
2889
2890 default:
2891 value->kind = RTX_UNKNOWN;
2892 break;
2893 }
2894
2895 if (value->kind == RTX_INT && value->un.addr.base != 0
2896 && GET_CODE (value->un.addr.base) == UNSPEC)
2897 {
2898 /* For a simple UNSPEC, the base is set to the
2899 operand, the kind field is set to the index of
2900 the unspec expression.
2901 Together with the code below, in case that
2902 the operand is a SYMBOL_REF or LABEL_REF,
2903 the address of the string or the code_label
2904 is taken as base. */
2905 if (XVECLEN (value->un.addr.base, 0) == 1)
2906 {
2907 value->kind = RTX_UNSPEC + XINT (value->un.addr.base, 1);
2908 value->un.addr.base = XVECEXP (value->un.addr.base, 0, 0);
2909 }
2910 }
2911
2912 if (value->kind >= RTX_INT && value->un.addr.base != 0)
2913 switch (GET_CODE (value->un.addr.base))
2914 {
2915 case SYMBOL_REF:
2916 /* Use the string's address, not the SYMBOL_REF's address,
2917 for the sake of addresses of library routines. */
2918 value->un.addr.symbol = XSTR (value->un.addr.base, 0);
2919 value->un.addr.base = NULL_RTX;
2920 break;
2921
2922 case LABEL_REF:
2923 /* For a LABEL_REF, compare labels. */
2924 value->un.addr.base = XEXP (value->un.addr.base, 0);
2925
2926 default:
2927 break;
2928 }
2929 }
2930
2931 /* Given a MINUS expression, simplify it if both sides
2932 include the same symbol. */
2933
2934 rtx
2935 simplify_subtraction (x)
2936 rtx x;
2937 {
2938 struct rtx_const val0, val1;
2939
2940 decode_rtx_const (GET_MODE (x), XEXP (x, 0), &val0);
2941 decode_rtx_const (GET_MODE (x), XEXP (x, 1), &val1);
2942
2943 if (val0.kind >= RTX_INT
2944 && val0.kind == val1.kind
2945 && val0.un.addr.base == val1.un.addr.base
2946 && val0.un.addr.symbol == val1.un.addr.symbol)
2947 return GEN_INT (val0.un.addr.offset - val1.un.addr.offset);
2948
2949 return x;
2950 }
2951
2952 /* Compute a hash code for a constant RTL expression. */
2953
2954 static unsigned int
2955 const_hash_rtx (mode, x)
2956 enum machine_mode mode;
2957 rtx x;
2958 {
2959 union {
2960 struct rtx_const value;
2961 unsigned int data[sizeof(struct rtx_const) / sizeof (unsigned int)];
2962 } u;
2963
2964 unsigned int hi;
2965 size_t i;
2966
2967 decode_rtx_const (mode, x, &u.value);
2968
2969 /* Compute hashing function */
2970 hi = 0;
2971 for (i = 0; i < ARRAY_SIZE (u.data); i++)
2972 hi = hi * 613 + u.data[i];
2973
2974 return hi % MAX_RTX_HASH_TABLE;
2975 }
2976
2977 /* Compare a constant rtl object X with a constant-descriptor DESC.
2978 Return 1 if DESC describes a constant with the same value as X. */
2979
2980 static int
2981 compare_constant_rtx (mode, x, desc)
2982 enum machine_mode mode;
2983 rtx x;
2984 struct constant_descriptor_rtx *desc;
2985 {
2986 struct rtx_const value;
2987
2988 decode_rtx_const (mode, x, &value);
2989
2990 /* Compare constant contents. */
2991 return memcmp (&value, &desc->value, sizeof (struct rtx_const)) == 0;
2992 }
2993
2994 /* Construct a constant descriptor for the rtl-expression X.
2995 It is up to the caller to enter the descriptor in the hash table. */
2996
2997 static struct constant_descriptor_rtx *
2998 record_constant_rtx (mode, x)
2999 enum machine_mode mode;
3000 rtx x;
3001 {
3002 struct constant_descriptor_rtx *ptr;
3003
3004 ptr = (struct constant_descriptor_rtx *) ggc_alloc (sizeof (*ptr));
3005 decode_rtx_const (mode, x, &ptr->value);
3006
3007 return ptr;
3008 }
3009 \f
3010 /* Given a constant rtx X, return a MEM for the location in memory at which
3011 this constant has been placed. Return 0 if it not has been placed yet. */
3012
3013 rtx
3014 mem_for_const_double (x)
3015 rtx x;
3016 {
3017 enum machine_mode mode = GET_MODE (x);
3018 struct constant_descriptor_rtx *desc;
3019
3020 for (desc = const_rtx_hash_table[const_hash_rtx (mode, x)]; desc;
3021 desc = desc->next)
3022 if (compare_constant_rtx (mode, x, desc))
3023 return desc->rtl;
3024
3025 return 0;
3026 }
3027
3028 /* Given a constant rtx X, make (or find) a memory constant for its value
3029 and return a MEM rtx to refer to it in memory. */
3030
3031 rtx
3032 force_const_mem (mode, x)
3033 enum machine_mode mode;
3034 rtx x;
3035 {
3036 int hash;
3037 struct constant_descriptor_rtx *desc;
3038 char label[256];
3039 rtx def, symbol;
3040 struct pool_constant *pool;
3041 unsigned int align;
3042
3043 /* If we're not allowed to drop X into the constant pool, don't. */
3044 if ((*targetm.cannot_force_const_mem) (x))
3045 return NULL_RTX;
3046
3047 /* Compute hash code of X. Search the descriptors for that hash code
3048 to see if any of them describes X. If yes, we have an rtx to use. */
3049 hash = const_hash_rtx (mode, x);
3050 for (desc = const_rtx_hash_table[hash]; desc; desc = desc->next)
3051 if (compare_constant_rtx (mode, x, desc))
3052 return desc->rtl;
3053
3054 /* No constant equal to X is known to have been output.
3055 Make a constant descriptor to enter X in the hash table
3056 and make a MEM for it. */
3057 desc = record_constant_rtx (mode, x);
3058 desc->next = const_rtx_hash_table[hash];
3059 const_rtx_hash_table[hash] = desc;
3060
3061 /* Align the location counter as required by EXP's data type. */
3062 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3063 #ifdef CONSTANT_ALIGNMENT
3064 align = CONSTANT_ALIGNMENT (make_tree ((*lang_hooks.types.type_for_mode)
3065 (mode, 0), x), align);
3066 #endif
3067
3068 pool_offset += (align / BITS_PER_UNIT) - 1;
3069 pool_offset &= ~ ((align / BITS_PER_UNIT) - 1);
3070
3071 if (GET_CODE (x) == LABEL_REF)
3072 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3073
3074 /* Allocate a pool constant descriptor, fill it in, and chain it in. */
3075 pool = (struct pool_constant *) ggc_alloc (sizeof (struct pool_constant));
3076 pool->desc = desc;
3077 pool->constant = x;
3078 pool->mode = mode;
3079 pool->labelno = const_labelno;
3080 pool->align = align;
3081 pool->offset = pool_offset;
3082 pool->mark = 1;
3083 pool->next = 0;
3084
3085 if (last_pool == 0)
3086 first_pool = pool;
3087 else
3088 last_pool->next = pool;
3089
3090 last_pool = pool;
3091 pool_offset += GET_MODE_SIZE (mode);
3092
3093 /* Create a string containing the label name, in LABEL. */
3094 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3095
3096 ++const_labelno;
3097
3098 /* Construct the SYMBOL_REF and the MEM. */
3099
3100 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3101 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
3102
3103 pool->desc->rtl = def = gen_rtx_MEM (mode, symbol);
3104 set_mem_attributes (def, (*lang_hooks.types.type_for_mode) (mode, 0), 1);
3105 RTX_UNCHANGING_P (def) = 1;
3106
3107 /* Add label to symbol hash table. */
3108 hash = SYMHASH (XSTR (symbol, 0));
3109 pool->next_sym = const_rtx_sym_hash_table[hash];
3110 const_rtx_sym_hash_table[hash] = pool;
3111
3112 /* Mark the symbol_ref as belonging to this constants pool. */
3113 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3114 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
3115 current_function_uses_const_pool = 1;
3116
3117 return def;
3118 }
3119 \f
3120 /* Given a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true, return a pointer to
3121 the corresponding pool_constant structure. */
3122
3123 static struct pool_constant *
3124 find_pool_constant (f, addr)
3125 struct function *f;
3126 rtx addr;
3127 {
3128 struct pool_constant *pool;
3129 const char *label = XSTR (addr, 0);
3130
3131 for (pool = f->varasm->x_const_rtx_sym_hash_table[SYMHASH (label)]; pool;
3132 pool = pool->next_sym)
3133 if (XSTR (XEXP (pool->desc->rtl, 0), 0) == label)
3134 return pool;
3135
3136 abort ();
3137 }
3138
3139 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3140
3141 rtx
3142 get_pool_constant (addr)
3143 rtx addr;
3144 {
3145 return (find_pool_constant (cfun, addr))->constant;
3146 }
3147
3148 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3149 and whether it has been output or not. */
3150
3151 rtx
3152 get_pool_constant_mark (addr, pmarked)
3153 rtx addr;
3154 bool *pmarked;
3155 {
3156 struct pool_constant *pool = find_pool_constant (cfun, addr);
3157 *pmarked = (pool->mark != 0);
3158 return pool->constant;
3159 }
3160
3161 /* Likewise, but for the constant pool of a specific function. */
3162
3163 rtx
3164 get_pool_constant_for_function (f, addr)
3165 struct function *f;
3166 rtx addr;
3167 {
3168 return (find_pool_constant (f, addr))->constant;
3169 }
3170
3171 /* Similar, return the mode. */
3172
3173 enum machine_mode
3174 get_pool_mode (addr)
3175 rtx addr;
3176 {
3177 return (find_pool_constant (cfun, addr))->mode;
3178 }
3179
3180 enum machine_mode
3181 get_pool_mode_for_function (f, addr)
3182 struct function *f;
3183 rtx addr;
3184 {
3185 return (find_pool_constant (f, addr))->mode;
3186 }
3187
3188 /* Similar, return the offset in the constant pool. */
3189
3190 int
3191 get_pool_offset (addr)
3192 rtx addr;
3193 {
3194 return (find_pool_constant (cfun, addr))->offset;
3195 }
3196
3197 /* Return the size of the constant pool. */
3198
3199 int
3200 get_pool_size ()
3201 {
3202 return pool_offset;
3203 }
3204 \f
3205 /* Write all the constants in the constant pool. */
3206
3207 void
3208 output_constant_pool (fnname, fndecl)
3209 const char *fnname ATTRIBUTE_UNUSED;
3210 tree fndecl ATTRIBUTE_UNUSED;
3211 {
3212 struct pool_constant *pool;
3213 rtx x;
3214 REAL_VALUE_TYPE r;
3215
3216 /* It is possible for gcc to call force_const_mem and then to later
3217 discard the instructions which refer to the constant. In such a
3218 case we do not need to output the constant. */
3219 mark_constant_pool ();
3220
3221 #ifdef ASM_OUTPUT_POOL_PROLOGUE
3222 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool_offset);
3223 #endif
3224
3225 for (pool = first_pool; pool; pool = pool->next)
3226 {
3227 rtx tmp;
3228
3229 x = pool->constant;
3230
3231 if (! pool->mark)
3232 continue;
3233
3234 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3235 whose CODE_LABEL has been deleted. This can occur if a jump table
3236 is eliminated by optimization. If so, write a constant of zero
3237 instead. Note that this can also happen by turning the
3238 CODE_LABEL into a NOTE. */
3239 /* ??? This seems completely and utterly wrong. Certainly it's
3240 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3241 functioning even with INSN_DELETED_P and friends. */
3242
3243 tmp = x;
3244 switch (GET_CODE (x))
3245 {
3246 case CONST:
3247 if (GET_CODE (XEXP (x, 0)) != PLUS
3248 || GET_CODE (XEXP (XEXP (x, 0), 0)) != LABEL_REF)
3249 break;
3250 tmp = XEXP (XEXP (x, 0), 0);
3251 /* FALLTHRU */
3252
3253 case LABEL_REF:
3254 tmp = XEXP (x, 0);
3255 if (INSN_DELETED_P (tmp)
3256 || (GET_CODE (tmp) == NOTE
3257 && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_DELETED))
3258 {
3259 abort ();
3260 x = const0_rtx;
3261 }
3262 break;
3263
3264 default:
3265 break;
3266 }
3267
3268 /* First switch to correct section. */
3269 (*targetm.asm_out.select_rtx_section) (pool->mode, x, pool->align);
3270
3271 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3272 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, pool->mode,
3273 pool->align, pool->labelno, done);
3274 #endif
3275
3276 assemble_align (pool->align);
3277
3278 /* Output the label. */
3279 (*targetm.asm_out.internal_label) (asm_out_file, "LC", pool->labelno);
3280
3281 /* Output the value of the constant itself. */
3282 switch (GET_MODE_CLASS (pool->mode))
3283 {
3284 case MODE_FLOAT:
3285 if (GET_CODE (x) != CONST_DOUBLE)
3286 abort ();
3287
3288 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3289 assemble_real (r, pool->mode, pool->align);
3290 break;
3291
3292 case MODE_INT:
3293 case MODE_PARTIAL_INT:
3294 assemble_integer (x, GET_MODE_SIZE (pool->mode), pool->align, 1);
3295 break;
3296
3297 case MODE_VECTOR_FLOAT:
3298 {
3299 int i, units;
3300 rtx elt;
3301
3302 if (GET_CODE (x) != CONST_VECTOR)
3303 abort ();
3304
3305 units = CONST_VECTOR_NUNITS (x);
3306
3307 for (i = 0; i < units; i++)
3308 {
3309 elt = CONST_VECTOR_ELT (x, i);
3310 REAL_VALUE_FROM_CONST_DOUBLE (r, elt);
3311 assemble_real (r, GET_MODE_INNER (pool->mode), pool->align);
3312 }
3313 }
3314 break;
3315
3316 case MODE_VECTOR_INT:
3317 {
3318 int i, units;
3319 rtx elt;
3320
3321 if (GET_CODE (x) != CONST_VECTOR)
3322 abort ();
3323
3324 units = CONST_VECTOR_NUNITS (x);
3325
3326 for (i = 0; i < units; i++)
3327 {
3328 elt = CONST_VECTOR_ELT (x, i);
3329 assemble_integer (elt, GET_MODE_UNIT_SIZE (pool->mode),
3330 pool->align, 1);
3331 }
3332 }
3333 break;
3334
3335 default:
3336 abort ();
3337 }
3338
3339 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3340 sections have proper size. */
3341 if (pool->align > GET_MODE_BITSIZE (pool->mode)
3342 && in_section == in_named
3343 && get_named_section_flags (in_named_name) & SECTION_MERGE)
3344 assemble_align (pool->align);
3345
3346 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3347 done: ;
3348 #endif
3349 }
3350
3351 #ifdef ASM_OUTPUT_POOL_EPILOGUE
3352 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool_offset);
3353 #endif
3354
3355 /* Done with this pool. */
3356 first_pool = last_pool = 0;
3357 }
3358
3359 /* Look through the instructions for this function, and mark all the
3360 entries in the constant pool which are actually being used. Emit
3361 deferred constants which have indeed been used. */
3362
3363 static void
3364 mark_constant_pool ()
3365 {
3366 rtx insn;
3367 rtx link;
3368 struct pool_constant *pool;
3369
3370 if (first_pool == 0 && n_deferred_constants == 0)
3371 return;
3372
3373 for (pool = first_pool; pool; pool = pool->next)
3374 pool->mark = 0;
3375
3376 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3377 if (INSN_P (insn))
3378 mark_constants (PATTERN (insn));
3379
3380 for (link = current_function_epilogue_delay_list;
3381 link;
3382 link = XEXP (link, 1))
3383 {
3384 insn = XEXP (link, 0);
3385
3386 if (INSN_P (insn))
3387 mark_constants (PATTERN (insn));
3388 }
3389 }
3390
3391 /* Look through appropriate parts of X, marking all entries in the
3392 constant pool which are actually being used. Entries that are only
3393 referenced by other constants are also marked as used. Emit
3394 deferred strings that are used. */
3395
3396 static void
3397 mark_constants (x)
3398 rtx x;
3399 {
3400 int i;
3401 const char *format_ptr;
3402
3403 if (x == 0)
3404 return;
3405
3406 if (GET_CODE (x) == SYMBOL_REF)
3407 {
3408 mark_constant (&x, NULL);
3409 return;
3410 }
3411
3412 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3413 insns, not any notes that may be attached. We don't want to mark
3414 a constant just because it happens to appear in a REG_EQUIV note. */
3415 if (INSN_P (x))
3416 {
3417 mark_constants (PATTERN (x));
3418 return;
3419 }
3420
3421 format_ptr = GET_RTX_FORMAT (GET_CODE (x));
3422
3423 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (x)); i++)
3424 {
3425 switch (*format_ptr++)
3426 {
3427 case 'e':
3428 mark_constants (XEXP (x, i));
3429 break;
3430
3431 case 'E':
3432 if (XVEC (x, i) != 0)
3433 {
3434 int j;
3435
3436 for (j = 0; j < XVECLEN (x, i); j++)
3437 mark_constants (XVECEXP (x, i, j));
3438 }
3439 break;
3440
3441 case 'S':
3442 case 's':
3443 case '0':
3444 case 'i':
3445 case 'w':
3446 case 'n':
3447 case 'u':
3448 case 'B':
3449 break;
3450
3451 default:
3452 abort ();
3453 }
3454 }
3455 }
3456
3457 /* Given a SYMBOL_REF CURRENT_RTX, mark it and all constants it refers
3458 to as used. Emit referenced deferred strings. This function can
3459 be used with for_each_rtx to mark all SYMBOL_REFs in an rtx. */
3460
3461 static int
3462 mark_constant (current_rtx, data)
3463 rtx *current_rtx;
3464 void *data ATTRIBUTE_UNUSED;
3465 {
3466 rtx x = *current_rtx;
3467
3468 if (x == NULL_RTX)
3469 return 0;
3470
3471 else if (GET_CODE (x) == SYMBOL_REF)
3472 {
3473 if (CONSTANT_POOL_ADDRESS_P (x))
3474 {
3475 struct pool_constant *pool = find_pool_constant (cfun, x);
3476 if (pool->mark == 0)
3477 {
3478 pool->mark = 1;
3479 for_each_rtx (&(pool->constant), &mark_constant, NULL);
3480 }
3481 else
3482 return -1;
3483 }
3484 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3485 {
3486 tree exp = SYMBOL_REF_DECL (x);
3487 if (!TREE_ASM_WRITTEN (exp))
3488 {
3489 n_deferred_constants--;
3490 output_constant_def_contents (x);
3491 }
3492 }
3493 }
3494 return 0;
3495 }
3496 \f
3497 /* Find all the constants whose addresses are referenced inside of EXP,
3498 and make sure assembler code with a label has been output for each one.
3499 Indicate whether an ADDR_EXPR has been encountered. */
3500
3501 static int
3502 output_addressed_constants (exp)
3503 tree exp;
3504 {
3505 int reloc = 0, reloc2;
3506 tree tem;
3507
3508 /* Give the front-end a chance to convert VALUE to something that
3509 looks more like a constant to the back-end. */
3510 exp = (*lang_hooks.expand_constant) (exp);
3511
3512 switch (TREE_CODE (exp))
3513 {
3514 case ADDR_EXPR:
3515 case FDESC_EXPR:
3516 /* Go inside any operations that get_inner_reference can handle and see
3517 if what's inside is a constant: no need to do anything here for
3518 addresses of variables or functions. */
3519 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
3520 tem = TREE_OPERAND (tem, 0))
3521 ;
3522
3523 if (TREE_CODE_CLASS (TREE_CODE (tem)) == 'c'
3524 || TREE_CODE (tem) == CONSTRUCTOR)
3525 output_constant_def (tem, 0);
3526
3527 if (TREE_PUBLIC (tem))
3528 reloc |= 2;
3529 else
3530 reloc |= 1;
3531 break;
3532
3533 case PLUS_EXPR:
3534 reloc = output_addressed_constants (TREE_OPERAND (exp, 0));
3535 reloc |= output_addressed_constants (TREE_OPERAND (exp, 1));
3536 break;
3537
3538 case MINUS_EXPR:
3539 reloc = output_addressed_constants (TREE_OPERAND (exp, 0));
3540 reloc2 = output_addressed_constants (TREE_OPERAND (exp, 1));
3541 /* The difference of two local labels is computable at link time. */
3542 if (reloc == 1 && reloc2 == 1)
3543 reloc = 0;
3544 else
3545 reloc |= reloc2;
3546 break;
3547
3548 case NOP_EXPR:
3549 case CONVERT_EXPR:
3550 case NON_LVALUE_EXPR:
3551 reloc = output_addressed_constants (TREE_OPERAND (exp, 0));
3552 break;
3553
3554 case CONSTRUCTOR:
3555 for (tem = CONSTRUCTOR_ELTS (exp); tem; tem = TREE_CHAIN (tem))
3556 if (TREE_VALUE (tem) != 0)
3557 reloc |= output_addressed_constants (TREE_VALUE (tem));
3558
3559 break;
3560
3561 default:
3562 break;
3563 }
3564 return reloc;
3565 }
3566 \f
3567 /* Return nonzero if VALUE is a valid constant-valued expression
3568 for use in initializing a static variable; one that can be an
3569 element of a "constant" initializer.
3570
3571 Return null_pointer_node if the value is absolute;
3572 if it is relocatable, return the variable that determines the relocation.
3573 We assume that VALUE has been folded as much as possible;
3574 therefore, we do not need to check for such things as
3575 arithmetic-combinations of integers. */
3576
3577 tree
3578 initializer_constant_valid_p (value, endtype)
3579 tree value;
3580 tree endtype;
3581 {
3582 /* Give the front-end a chance to convert VALUE to something that
3583 looks more like a constant to the back-end. */
3584 value = (*lang_hooks.expand_constant) (value);
3585
3586 switch (TREE_CODE (value))
3587 {
3588 case CONSTRUCTOR:
3589 if ((TREE_CODE (TREE_TYPE (value)) == UNION_TYPE
3590 || TREE_CODE (TREE_TYPE (value)) == RECORD_TYPE)
3591 && TREE_CONSTANT (value)
3592 && CONSTRUCTOR_ELTS (value))
3593 return
3594 initializer_constant_valid_p (TREE_VALUE (CONSTRUCTOR_ELTS (value)),
3595 endtype);
3596
3597 return TREE_STATIC (value) ? null_pointer_node : 0;
3598
3599 case INTEGER_CST:
3600 case VECTOR_CST:
3601 case REAL_CST:
3602 case STRING_CST:
3603 case COMPLEX_CST:
3604 return null_pointer_node;
3605
3606 case ADDR_EXPR:
3607 case FDESC_EXPR:
3608 return staticp (TREE_OPERAND (value, 0)) ? TREE_OPERAND (value, 0) : 0;
3609
3610 case VIEW_CONVERT_EXPR:
3611 case NON_LVALUE_EXPR:
3612 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3613
3614 case CONVERT_EXPR:
3615 case NOP_EXPR:
3616 /* Allow conversions between pointer types. */
3617 if (POINTER_TYPE_P (TREE_TYPE (value))
3618 && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3619 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3620
3621 /* Allow conversions between real types. */
3622 if (FLOAT_TYPE_P (TREE_TYPE (value))
3623 && FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3624 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3625
3626 /* Allow length-preserving conversions between integer types. */
3627 if (INTEGRAL_TYPE_P (TREE_TYPE (value))
3628 && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0)))
3629 && (TYPE_PRECISION (TREE_TYPE (value))
3630 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0)))))
3631 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3632
3633 /* Allow conversions between other integer types only if
3634 explicit value. */
3635 if (INTEGRAL_TYPE_P (TREE_TYPE (value))
3636 && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3637 {
3638 tree inner = initializer_constant_valid_p (TREE_OPERAND (value, 0),
3639 endtype);
3640 if (inner == null_pointer_node)
3641 return null_pointer_node;
3642 break;
3643 }
3644
3645 /* Allow (int) &foo provided int is as wide as a pointer. */
3646 if (INTEGRAL_TYPE_P (TREE_TYPE (value))
3647 && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0)))
3648 && (TYPE_PRECISION (TREE_TYPE (value))
3649 >= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0)))))
3650 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
3651 endtype);
3652
3653 /* Likewise conversions from int to pointers, but also allow
3654 conversions from 0. */
3655 if (POINTER_TYPE_P (TREE_TYPE (value))
3656 && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3657 {
3658 if (integer_zerop (TREE_OPERAND (value, 0)))
3659 return null_pointer_node;
3660 else if (TYPE_PRECISION (TREE_TYPE (value))
3661 <= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0))))
3662 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
3663 endtype);
3664 }
3665
3666 /* Allow conversions to union types if the value inside is okay. */
3667 if (TREE_CODE (TREE_TYPE (value)) == UNION_TYPE)
3668 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
3669 endtype);
3670 break;
3671
3672 case PLUS_EXPR:
3673 if (! INTEGRAL_TYPE_P (endtype)
3674 || TYPE_PRECISION (endtype) >= POINTER_SIZE)
3675 {
3676 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0),
3677 endtype);
3678 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1),
3679 endtype);
3680 /* If either term is absolute, use the other terms relocation. */
3681 if (valid0 == null_pointer_node)
3682 return valid1;
3683 if (valid1 == null_pointer_node)
3684 return valid0;
3685 }
3686 break;
3687
3688 case MINUS_EXPR:
3689 if (! INTEGRAL_TYPE_P (endtype)
3690 || TYPE_PRECISION (endtype) >= POINTER_SIZE)
3691 {
3692 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0),
3693 endtype);
3694 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1),
3695 endtype);
3696 /* Win if second argument is absolute. */
3697 if (valid1 == null_pointer_node)
3698 return valid0;
3699 /* Win if both arguments have the same relocation.
3700 Then the value is absolute. */
3701 if (valid0 == valid1 && valid0 != 0)
3702 return null_pointer_node;
3703
3704 /* Since GCC guarantees that string constants are unique in the
3705 generated code, a subtraction between two copies of the same
3706 constant string is absolute. */
3707 if (valid0 && TREE_CODE (valid0) == STRING_CST &&
3708 valid1 && TREE_CODE (valid1) == STRING_CST &&
3709 TREE_STRING_POINTER (valid0) == TREE_STRING_POINTER (valid1))
3710 return null_pointer_node;
3711 }
3712
3713 /* Support differences between labels. */
3714 if (INTEGRAL_TYPE_P (endtype))
3715 {
3716 tree op0, op1;
3717 op0 = TREE_OPERAND (value, 0);
3718 op1 = TREE_OPERAND (value, 1);
3719
3720 /* Like STRIP_NOPS except allow the operand mode to widen.
3721 This works around a feature of fold that simplifies
3722 (int)(p1 - p2) to ((int)p1 - (int)p2) under the theory
3723 that the narrower operation is cheaper. */
3724
3725 while (TREE_CODE (op0) == NOP_EXPR
3726 || TREE_CODE (op0) == CONVERT_EXPR
3727 || TREE_CODE (op0) == NON_LVALUE_EXPR)
3728 {
3729 tree inner = TREE_OPERAND (op0, 0);
3730 if (inner == error_mark_node
3731 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
3732 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
3733 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
3734 break;
3735 op0 = inner;
3736 }
3737
3738 while (TREE_CODE (op1) == NOP_EXPR
3739 || TREE_CODE (op1) == CONVERT_EXPR
3740 || TREE_CODE (op1) == NON_LVALUE_EXPR)
3741 {
3742 tree inner = TREE_OPERAND (op1, 0);
3743 if (inner == error_mark_node
3744 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
3745 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
3746 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
3747 break;
3748 op1 = inner;
3749 }
3750
3751 if (TREE_CODE (op0) == ADDR_EXPR
3752 && TREE_CODE (TREE_OPERAND (op0, 0)) == LABEL_DECL
3753 && TREE_CODE (op1) == ADDR_EXPR
3754 && TREE_CODE (TREE_OPERAND (op1, 0)) == LABEL_DECL)
3755 return null_pointer_node;
3756 }
3757 break;
3758
3759 default:
3760 break;
3761 }
3762
3763 return 0;
3764 }
3765 \f
3766 /* Output assembler code for constant EXP to FILE, with no label.
3767 This includes the pseudo-op such as ".int" or ".byte", and a newline.
3768 Assumes output_addressed_constants has been done on EXP already.
3769
3770 Generate exactly SIZE bytes of assembler data, padding at the end
3771 with zeros if necessary. SIZE must always be specified.
3772
3773 SIZE is important for structure constructors,
3774 since trailing members may have been omitted from the constructor.
3775 It is also important for initialization of arrays from string constants
3776 since the full length of the string constant might not be wanted.
3777 It is also needed for initialization of unions, where the initializer's
3778 type is just one member, and that may not be as long as the union.
3779
3780 There a case in which we would fail to output exactly SIZE bytes:
3781 for a structure constructor that wants to produce more than SIZE bytes.
3782 But such constructors will never be generated for any possible input.
3783
3784 ALIGN is the alignment of the data in bits. */
3785
3786 void
3787 output_constant (exp, size, align)
3788 tree exp;
3789 unsigned HOST_WIDE_INT size;
3790 unsigned int align;
3791 {
3792 enum tree_code code;
3793 unsigned HOST_WIDE_INT thissize;
3794
3795 /* Some front-ends use constants other than the standard language-independent
3796 varieties, but which may still be output directly. Give the front-end a
3797 chance to convert EXP to a language-independent representation. */
3798 exp = (*lang_hooks.expand_constant) (exp);
3799
3800 if (size == 0 || flag_syntax_only)
3801 return;
3802
3803 /* Eliminate any conversions since we'll be outputting the underlying
3804 constant. */
3805 while (TREE_CODE (exp) == NOP_EXPR || TREE_CODE (exp) == CONVERT_EXPR
3806 || TREE_CODE (exp) == NON_LVALUE_EXPR
3807 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
3808 exp = TREE_OPERAND (exp, 0);
3809
3810 code = TREE_CODE (TREE_TYPE (exp));
3811 thissize = int_size_in_bytes (TREE_TYPE (exp));
3812
3813 /* Allow a constructor with no elements for any data type.
3814 This means to fill the space with zeros. */
3815 if (TREE_CODE (exp) == CONSTRUCTOR && CONSTRUCTOR_ELTS (exp) == 0)
3816 {
3817 assemble_zeros (size);
3818 return;
3819 }
3820
3821 if (TREE_CODE (exp) == FDESC_EXPR)
3822 {
3823 #ifdef ASM_OUTPUT_FDESC
3824 HOST_WIDE_INT part = tree_low_cst (TREE_OPERAND (exp, 1), 0);
3825 tree decl = TREE_OPERAND (exp, 0);
3826 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
3827 #else
3828 abort ();
3829 #endif
3830 return;
3831 }
3832
3833 /* Now output the underlying data. If we've handling the padding, return.
3834 Otherwise, break and ensure THISSIZE is the size written. */
3835 switch (code)
3836 {
3837 case CHAR_TYPE:
3838 case BOOLEAN_TYPE:
3839 case INTEGER_TYPE:
3840 case ENUMERAL_TYPE:
3841 case POINTER_TYPE:
3842 case REFERENCE_TYPE:
3843 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
3844 EXPAND_INITIALIZER),
3845 size, align, 0))
3846 error ("initializer for integer value is too complicated");
3847 break;
3848
3849 case REAL_TYPE:
3850 if (TREE_CODE (exp) != REAL_CST)
3851 error ("initializer for floating value is not a floating constant");
3852
3853 assemble_real (TREE_REAL_CST (exp),
3854 mode_for_size (size * BITS_PER_UNIT, MODE_FLOAT, 0),
3855 align);
3856 break;
3857
3858 case COMPLEX_TYPE:
3859 output_constant (TREE_REALPART (exp), thissize / 2, align);
3860 output_constant (TREE_IMAGPART (exp), thissize / 2,
3861 min_align (align, BITS_PER_UNIT * (thissize / 2)));
3862 break;
3863
3864 case ARRAY_TYPE:
3865 case VECTOR_TYPE:
3866 if (TREE_CODE (exp) == CONSTRUCTOR)
3867 {
3868 output_constructor (exp, size, align);
3869 return;
3870 }
3871 else if (TREE_CODE (exp) == STRING_CST)
3872 {
3873 thissize = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp),
3874 size);
3875 assemble_string (TREE_STRING_POINTER (exp), thissize);
3876 }
3877 else if (TREE_CODE (exp) == VECTOR_CST)
3878 {
3879 int elt_size;
3880 tree link;
3881 unsigned int nalign;
3882 enum machine_mode inner;
3883
3884 inner = GET_MODE_INNER (TYPE_MODE (TREE_TYPE (exp)));
3885 nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
3886
3887 elt_size = GET_MODE_UNIT_SIZE (TYPE_MODE (TREE_TYPE (exp)));
3888
3889 link = TREE_VECTOR_CST_ELTS (exp);
3890 output_constant (TREE_VALUE (link), elt_size, align);
3891 while ((link = TREE_CHAIN (link)) != NULL)
3892 output_constant (TREE_VALUE (link), elt_size, nalign);
3893 }
3894 else
3895 abort ();
3896 break;
3897
3898 case RECORD_TYPE:
3899 case UNION_TYPE:
3900 if (TREE_CODE (exp) == CONSTRUCTOR)
3901 output_constructor (exp, size, align);
3902 else
3903 abort ();
3904 return;
3905
3906 case SET_TYPE:
3907 if (TREE_CODE (exp) == INTEGER_CST)
3908 assemble_integer (expand_expr (exp, NULL_RTX,
3909 VOIDmode, EXPAND_INITIALIZER),
3910 thissize, align, 1);
3911 else if (TREE_CODE (exp) == CONSTRUCTOR)
3912 {
3913 unsigned char *buffer = (unsigned char *) alloca (thissize);
3914 if (get_set_constructor_bytes (exp, buffer, thissize))
3915 abort ();
3916 assemble_string ((char *) buffer, thissize);
3917 }
3918 else
3919 error ("unknown set constructor type");
3920 return;
3921
3922 case ERROR_MARK:
3923 return;
3924
3925 default:
3926 abort ();
3927 }
3928
3929 if (size > thissize)
3930 assemble_zeros (size - thissize);
3931 }
3932
3933 \f
3934 /* Subroutine of output_constructor, used for computing the size of
3935 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
3936 type with an unspecified upper bound. */
3937
3938 static unsigned HOST_WIDE_INT
3939 array_size_for_constructor (val)
3940 tree val;
3941 {
3942 tree max_index, i;
3943
3944 /* This code used to attempt to handle string constants that are not
3945 arrays of single-bytes, but nothing else does, so there's no point in
3946 doing it here. */
3947 if (TREE_CODE (val) == STRING_CST)
3948 return TREE_STRING_LENGTH (val);
3949
3950 max_index = NULL_TREE;
3951 for (i = CONSTRUCTOR_ELTS (val); i; i = TREE_CHAIN (i))
3952 {
3953 tree index = TREE_PURPOSE (i);
3954
3955 if (TREE_CODE (index) == RANGE_EXPR)
3956 index = TREE_OPERAND (index, 1);
3957 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
3958 max_index = index;
3959 }
3960
3961 if (max_index == NULL_TREE)
3962 return 0;
3963
3964 /* Compute the total number of array elements. */
3965 i = size_binop (MINUS_EXPR, convert (sizetype, max_index),
3966 convert (sizetype,
3967 TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)))));
3968 i = size_binop (PLUS_EXPR, i, convert (sizetype, integer_one_node));
3969
3970 /* Multiply by the array element unit size to find number of bytes. */
3971 i = size_binop (MULT_EXPR, i, TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
3972
3973 return tree_low_cst (i, 1);
3974 }
3975
3976 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
3977 Generate at least SIZE bytes, padding if necessary. */
3978
3979 static void
3980 output_constructor (exp, size, align)
3981 tree exp;
3982 unsigned HOST_WIDE_INT size;
3983 unsigned int align;
3984 {
3985 tree type = TREE_TYPE (exp);
3986 tree link, field = 0;
3987 tree min_index = 0;
3988 /* Number of bytes output or skipped so far.
3989 In other words, current position within the constructor. */
3990 HOST_WIDE_INT total_bytes = 0;
3991 /* Nonzero means BYTE contains part of a byte, to be output. */
3992 int byte_buffer_in_use = 0;
3993 int byte = 0;
3994
3995 if (HOST_BITS_PER_WIDE_INT < BITS_PER_UNIT)
3996 abort ();
3997
3998 if (TREE_CODE (type) == RECORD_TYPE)
3999 field = TYPE_FIELDS (type);
4000
4001 if (TREE_CODE (type) == ARRAY_TYPE
4002 && TYPE_DOMAIN (type) != 0)
4003 min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (type));
4004
4005 /* As LINK goes through the elements of the constant,
4006 FIELD goes through the structure fields, if the constant is a structure.
4007 if the constant is a union, then we override this,
4008 by getting the field from the TREE_LIST element.
4009 But the constant could also be an array. Then FIELD is zero.
4010
4011 There is always a maximum of one element in the chain LINK for unions
4012 (even if the initializer in a source program incorrectly contains
4013 more one). */
4014 for (link = CONSTRUCTOR_ELTS (exp);
4015 link;
4016 link = TREE_CHAIN (link),
4017 field = field ? TREE_CHAIN (field) : 0)
4018 {
4019 tree val = TREE_VALUE (link);
4020 tree index = 0;
4021
4022 /* The element in a union constructor specifies the proper field
4023 or index. */
4024 if ((TREE_CODE (type) == RECORD_TYPE || TREE_CODE (type) == UNION_TYPE
4025 || TREE_CODE (type) == QUAL_UNION_TYPE)
4026 && TREE_PURPOSE (link) != 0)
4027 field = TREE_PURPOSE (link);
4028
4029 else if (TREE_CODE (type) == ARRAY_TYPE)
4030 index = TREE_PURPOSE (link);
4031
4032 /* Eliminate the marker that makes a cast not be an lvalue. */
4033 if (val != 0)
4034 STRIP_NOPS (val);
4035
4036 if (index && TREE_CODE (index) == RANGE_EXPR)
4037 {
4038 unsigned HOST_WIDE_INT fieldsize
4039 = int_size_in_bytes (TREE_TYPE (type));
4040 HOST_WIDE_INT lo_index = tree_low_cst (TREE_OPERAND (index, 0), 0);
4041 HOST_WIDE_INT hi_index = tree_low_cst (TREE_OPERAND (index, 1), 0);
4042 HOST_WIDE_INT index;
4043 unsigned int align2 = min_align (align, fieldsize * BITS_PER_UNIT);
4044
4045 for (index = lo_index; index <= hi_index; index++)
4046 {
4047 /* Output the element's initial value. */
4048 if (val == 0)
4049 assemble_zeros (fieldsize);
4050 else
4051 output_constant (val, fieldsize, align2);
4052
4053 /* Count its size. */
4054 total_bytes += fieldsize;
4055 }
4056 }
4057 else if (field == 0 || !DECL_BIT_FIELD (field))
4058 {
4059 /* An element that is not a bit-field. */
4060
4061 unsigned HOST_WIDE_INT fieldsize;
4062 /* Since this structure is static,
4063 we know the positions are constant. */
4064 HOST_WIDE_INT pos = field ? int_byte_position (field) : 0;
4065 unsigned int align2;
4066
4067 if (index != 0)
4068 pos = (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (val)), 1)
4069 * (tree_low_cst (index, 0) - tree_low_cst (min_index, 0)));
4070
4071 /* Output any buffered-up bit-fields preceding this element. */
4072 if (byte_buffer_in_use)
4073 {
4074 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4075 total_bytes++;
4076 byte_buffer_in_use = 0;
4077 }
4078
4079 /* Advance to offset of this element.
4080 Note no alignment needed in an array, since that is guaranteed
4081 if each element has the proper size. */
4082 if ((field != 0 || index != 0) && pos != total_bytes)
4083 {
4084 assemble_zeros (pos - total_bytes);
4085 total_bytes = pos;
4086 }
4087
4088 /* Find the alignment of this element. */
4089 align2 = min_align (align, BITS_PER_UNIT * pos);
4090
4091 /* Determine size this element should occupy. */
4092 if (field)
4093 {
4094 fieldsize = 0;
4095
4096 /* If this is an array with an unspecified upper bound,
4097 the initializer determines the size. */
4098 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
4099 but we cannot do this until the deprecated support for
4100 initializing zero-length array members is removed. */
4101 if (TREE_CODE (TREE_TYPE (field)) == ARRAY_TYPE
4102 && TYPE_DOMAIN (TREE_TYPE (field))
4103 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (field))))
4104 {
4105 fieldsize = array_size_for_constructor (val);
4106 /* Given a non-empty initialization, this field had
4107 better be last. */
4108 if (fieldsize != 0 && TREE_CHAIN (field) != NULL_TREE)
4109 abort ();
4110 }
4111 else if (DECL_SIZE_UNIT (field))
4112 {
4113 /* ??? This can't be right. If the decl size overflows
4114 a host integer we will silently emit no data. */
4115 if (host_integerp (DECL_SIZE_UNIT (field), 1))
4116 fieldsize = tree_low_cst (DECL_SIZE_UNIT (field), 1);
4117 }
4118 }
4119 else
4120 fieldsize = int_size_in_bytes (TREE_TYPE (type));
4121
4122 /* Output the element's initial value. */
4123 if (val == 0)
4124 assemble_zeros (fieldsize);
4125 else
4126 output_constant (val, fieldsize, align2);
4127
4128 /* Count its size. */
4129 total_bytes += fieldsize;
4130 }
4131 else if (val != 0 && TREE_CODE (val) != INTEGER_CST)
4132 error ("invalid initial value for member `%s'",
4133 IDENTIFIER_POINTER (DECL_NAME (field)));
4134 else
4135 {
4136 /* Element that is a bit-field. */
4137
4138 HOST_WIDE_INT next_offset = int_bit_position (field);
4139 HOST_WIDE_INT end_offset
4140 = (next_offset + tree_low_cst (DECL_SIZE (field), 1));
4141
4142 if (val == 0)
4143 val = integer_zero_node;
4144
4145 /* If this field does not start in this (or, next) byte,
4146 skip some bytes. */
4147 if (next_offset / BITS_PER_UNIT != total_bytes)
4148 {
4149 /* Output remnant of any bit field in previous bytes. */
4150 if (byte_buffer_in_use)
4151 {
4152 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4153 total_bytes++;
4154 byte_buffer_in_use = 0;
4155 }
4156
4157 /* If still not at proper byte, advance to there. */
4158 if (next_offset / BITS_PER_UNIT != total_bytes)
4159 {
4160 assemble_zeros (next_offset / BITS_PER_UNIT - total_bytes);
4161 total_bytes = next_offset / BITS_PER_UNIT;
4162 }
4163 }
4164
4165 if (! byte_buffer_in_use)
4166 byte = 0;
4167
4168 /* We must split the element into pieces that fall within
4169 separate bytes, and combine each byte with previous or
4170 following bit-fields. */
4171
4172 /* next_offset is the offset n fbits from the beginning of
4173 the structure to the next bit of this element to be processed.
4174 end_offset is the offset of the first bit past the end of
4175 this element. */
4176 while (next_offset < end_offset)
4177 {
4178 int this_time;
4179 int shift;
4180 HOST_WIDE_INT value;
4181 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
4182 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
4183
4184 /* Advance from byte to byte
4185 within this element when necessary. */
4186 while (next_byte != total_bytes)
4187 {
4188 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4189 total_bytes++;
4190 byte = 0;
4191 }
4192
4193 /* Number of bits we can process at once
4194 (all part of the same byte). */
4195 this_time = MIN (end_offset - next_offset,
4196 BITS_PER_UNIT - next_bit);
4197 if (BYTES_BIG_ENDIAN)
4198 {
4199 /* On big-endian machine, take the most significant bits
4200 first (of the bits that are significant)
4201 and put them into bytes from the most significant end. */
4202 shift = end_offset - next_offset - this_time;
4203
4204 /* Don't try to take a bunch of bits that cross
4205 the word boundary in the INTEGER_CST. We can
4206 only select bits from the LOW or HIGH part
4207 not from both. */
4208 if (shift < HOST_BITS_PER_WIDE_INT
4209 && shift + this_time > HOST_BITS_PER_WIDE_INT)
4210 {
4211 this_time = shift + this_time - HOST_BITS_PER_WIDE_INT;
4212 shift = HOST_BITS_PER_WIDE_INT;
4213 }
4214
4215 /* Now get the bits from the appropriate constant word. */
4216 if (shift < HOST_BITS_PER_WIDE_INT)
4217 value = TREE_INT_CST_LOW (val);
4218 else if (shift < 2 * HOST_BITS_PER_WIDE_INT)
4219 {
4220 value = TREE_INT_CST_HIGH (val);
4221 shift -= HOST_BITS_PER_WIDE_INT;
4222 }
4223 else
4224 abort ();
4225
4226 /* Get the result. This works only when:
4227 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
4228 byte |= (((value >> shift)
4229 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
4230 << (BITS_PER_UNIT - this_time - next_bit));
4231 }
4232 else
4233 {
4234 /* On little-endian machines,
4235 take first the least significant bits of the value
4236 and pack them starting at the least significant
4237 bits of the bytes. */
4238 shift = next_offset - int_bit_position (field);
4239
4240 /* Don't try to take a bunch of bits that cross
4241 the word boundary in the INTEGER_CST. We can
4242 only select bits from the LOW or HIGH part
4243 not from both. */
4244 if (shift < HOST_BITS_PER_WIDE_INT
4245 && shift + this_time > HOST_BITS_PER_WIDE_INT)
4246 this_time = (HOST_BITS_PER_WIDE_INT - shift);
4247
4248 /* Now get the bits from the appropriate constant word. */
4249 if (shift < HOST_BITS_PER_WIDE_INT)
4250 value = TREE_INT_CST_LOW (val);
4251 else if (shift < 2 * HOST_BITS_PER_WIDE_INT)
4252 {
4253 value = TREE_INT_CST_HIGH (val);
4254 shift -= HOST_BITS_PER_WIDE_INT;
4255 }
4256 else
4257 abort ();
4258
4259 /* Get the result. This works only when:
4260 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
4261 byte |= (((value >> shift)
4262 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
4263 << next_bit);
4264 }
4265
4266 next_offset += this_time;
4267 byte_buffer_in_use = 1;
4268 }
4269 }
4270 }
4271
4272 if (byte_buffer_in_use)
4273 {
4274 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4275 total_bytes++;
4276 }
4277
4278 if ((unsigned HOST_WIDE_INT)total_bytes < size)
4279 assemble_zeros (size - total_bytes);
4280 }
4281
4282 /* This TREE_LIST contains any weak symbol declarations waiting
4283 to be emitted. */
4284 static GTY(()) tree weak_decls;
4285
4286 /* Mark DECL as weak. */
4287
4288 static void
4289 mark_weak (decl)
4290 tree decl;
4291 {
4292 DECL_WEAK (decl) = 1;
4293
4294 if (DECL_RTL_SET_P (decl)
4295 && GET_CODE (DECL_RTL (decl)) == MEM
4296 && XEXP (DECL_RTL (decl), 0)
4297 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
4298 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
4299 }
4300
4301 /* Merge weak status between NEWDECL and OLDDECL. */
4302
4303 void
4304 merge_weak (newdecl, olddecl)
4305 tree newdecl;
4306 tree olddecl;
4307 {
4308 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
4309 return;
4310
4311 if (DECL_WEAK (newdecl))
4312 {
4313 tree wd;
4314
4315 /* NEWDECL is weak, but OLDDECL is not. */
4316
4317 /* If we already output the OLDDECL, we're in trouble; we can't
4318 go back and make it weak. This error cannot caught in
4319 declare_weak because the NEWDECL and OLDDECL was not yet
4320 been merged; therefore, TREE_ASM_WRITTEN was not set. */
4321 if (TREE_ASM_WRITTEN (olddecl))
4322 error_with_decl (newdecl,
4323 "weak declaration of `%s' must precede definition");
4324
4325 /* If we've already generated rtl referencing OLDDECL, we may
4326 have done so in a way that will not function properly with
4327 a weak symbol. */
4328 else if (TREE_USED (olddecl)
4329 && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)))
4330 warning_with_decl (newdecl, "weak declaration of `%s' after first use results in unspecified behavior");
4331
4332 if (SUPPORTS_WEAK)
4333 {
4334 /* We put the NEWDECL on the weak_decls list at some point.
4335 Replace it with the OLDDECL. */
4336 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
4337 if (TREE_VALUE (wd) == newdecl)
4338 {
4339 TREE_VALUE (wd) = olddecl;
4340 break;
4341 }
4342 /* We may not find the entry on the list. If NEWDECL is a
4343 weak alias, then we will have already called
4344 globalize_decl to remove the entry; in that case, we do
4345 not need to do anything. */
4346 }
4347
4348 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
4349 mark_weak (olddecl);
4350 }
4351 else
4352 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
4353 weak. Just update NEWDECL to indicate that it's weak too. */
4354 mark_weak (newdecl);
4355 }
4356
4357 /* Declare DECL to be a weak symbol. */
4358
4359 void
4360 declare_weak (decl)
4361 tree decl;
4362 {
4363 if (! TREE_PUBLIC (decl))
4364 error_with_decl (decl, "weak declaration of `%s' must be public");
4365 else if (TREE_CODE (decl) == FUNCTION_DECL && TREE_ASM_WRITTEN (decl))
4366 error_with_decl (decl, "weak declaration of `%s' must precede definition");
4367 else if (SUPPORTS_WEAK)
4368 {
4369 if (! DECL_WEAK (decl))
4370 weak_decls = tree_cons (NULL, decl, weak_decls);
4371 }
4372 else
4373 warning_with_decl (decl, "weak declaration of `%s' not supported");
4374
4375 mark_weak (decl);
4376 }
4377
4378 /* Emit any pending weak declarations. */
4379
4380 void
4381 weak_finish ()
4382 {
4383 tree t;
4384
4385 for (t = weak_decls; t; t = TREE_CHAIN (t))
4386 {
4387 tree decl = TREE_VALUE (t);
4388 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
4389 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
4390 #endif
4391
4392 if (! TREE_USED (decl))
4393 continue;
4394
4395 #ifdef ASM_WEAKEN_DECL
4396 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
4397 #else
4398 #ifdef ASM_WEAKEN_LABEL
4399 ASM_WEAKEN_LABEL (asm_out_file, name);
4400 #else
4401 #ifdef ASM_OUTPUT_WEAK_ALIAS
4402 warning ("only weak aliases are supported in this configuration");
4403 return;
4404 #endif
4405 #endif
4406 #endif
4407 }
4408 }
4409
4410 /* Emit the assembly bits to indicate that DECL is globally visible. */
4411
4412 static void
4413 globalize_decl (decl)
4414 tree decl;
4415 {
4416 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
4417
4418 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
4419 if (DECL_WEAK (decl))
4420 {
4421 tree *p, t;
4422
4423 #ifdef ASM_WEAKEN_DECL
4424 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
4425 #else
4426 ASM_WEAKEN_LABEL (asm_out_file, name);
4427 #endif
4428
4429 /* Remove this function from the pending weak list so that
4430 we do not emit multiple .weak directives for it. */
4431 for (p = &weak_decls; (t = *p) ; )
4432 {
4433 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
4434 *p = TREE_CHAIN (t);
4435 else
4436 p = &TREE_CHAIN (t);
4437 }
4438 return;
4439 }
4440 #endif
4441
4442 (*targetm.asm_out.globalize_label) (asm_out_file, name);
4443 }
4444
4445 /* Emit an assembler directive to make the symbol for DECL an alias to
4446 the symbol for TARGET. */
4447
4448 void
4449 assemble_alias (decl, target)
4450 tree decl, target ATTRIBUTE_UNUSED;
4451 {
4452 const char *name;
4453
4454 /* We must force creation of DECL_RTL for debug info generation, even though
4455 we don't use it here. */
4456 make_decl_rtl (decl, NULL);
4457
4458 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
4459
4460 #ifdef ASM_OUTPUT_DEF
4461 /* Make name accessible from other files, if appropriate. */
4462
4463 if (TREE_PUBLIC (decl))
4464 {
4465 globalize_decl (decl);
4466 maybe_assemble_visibility (decl);
4467 }
4468
4469 #ifdef ASM_OUTPUT_DEF_FROM_DECLS
4470 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
4471 #else
4472 ASM_OUTPUT_DEF (asm_out_file, name, IDENTIFIER_POINTER (target));
4473 #endif
4474 #else /* !ASM_OUTPUT_DEF */
4475 #if defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
4476 if (! DECL_WEAK (decl))
4477 warning ("only weak aliases are supported in this configuration");
4478
4479 #ifdef ASM_WEAKEN_DECL
4480 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
4481 #else
4482 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
4483 #endif
4484 #else
4485 warning ("alias definitions not supported in this configuration; ignored");
4486 #endif
4487 #endif
4488
4489 TREE_USED (decl) = 1;
4490 TREE_ASM_WRITTEN (decl) = 1;
4491 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
4492 }
4493
4494 /* Emit an assembler directive to set symbol for DECL visibility to
4495 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
4496
4497 void
4498 default_assemble_visibility (decl, vis)
4499 tree decl;
4500 int vis;
4501 {
4502 static const char * const visibility_types[] = {
4503 NULL, "internal", "hidden", "protected"
4504 };
4505
4506 const char *name, *type;
4507
4508 name = (IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)));
4509 type = visibility_types[vis];
4510
4511 #ifdef HAVE_GAS_HIDDEN
4512 fprintf (asm_out_file, "\t.%s\t", type);
4513 assemble_name (asm_out_file, name);
4514 fprintf (asm_out_file, "\n");
4515 #else
4516 warning ("visibility attribute not supported in this configuration; ignored");
4517 #endif
4518 }
4519
4520 /* A helper function to call assemble_visibility when needed for a decl. */
4521
4522 static void
4523 maybe_assemble_visibility (decl)
4524 tree decl;
4525 {
4526 enum symbol_visibility vis = decl_visibility (decl);
4527
4528 if (vis != VISIBILITY_DEFAULT)
4529 (* targetm.asm_out.visibility) (decl, vis);
4530 }
4531
4532 /* Returns 1 if the target configuration supports defining public symbols
4533 so that one of them will be chosen at link time instead of generating a
4534 multiply-defined symbol error, whether through the use of weak symbols or
4535 a target-specific mechanism for having duplicates discarded. */
4536
4537 int
4538 supports_one_only ()
4539 {
4540 if (SUPPORTS_ONE_ONLY)
4541 return 1;
4542 return SUPPORTS_WEAK;
4543 }
4544
4545 /* Set up DECL as a public symbol that can be defined in multiple
4546 translation units without generating a linker error. */
4547
4548 void
4549 make_decl_one_only (decl)
4550 tree decl;
4551 {
4552 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != FUNCTION_DECL)
4553 abort ();
4554
4555 TREE_PUBLIC (decl) = 1;
4556
4557 if (TREE_CODE (decl) == VAR_DECL
4558 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node))
4559 DECL_COMMON (decl) = 1;
4560 else if (SUPPORTS_ONE_ONLY)
4561 {
4562 #ifdef MAKE_DECL_ONE_ONLY
4563 MAKE_DECL_ONE_ONLY (decl);
4564 #endif
4565 DECL_ONE_ONLY (decl) = 1;
4566 }
4567 else if (SUPPORTS_WEAK)
4568 DECL_WEAK (decl) = 1;
4569 else
4570 abort ();
4571 }
4572
4573 void
4574 init_varasm_once ()
4575 {
4576 in_named_htab = htab_create_ggc (31, in_named_entry_hash,
4577 in_named_entry_eq, NULL);
4578 const_desc_htab = htab_create_ggc (1009, const_desc_hash,
4579 const_desc_eq, NULL);
4580
4581 const_alias_set = new_alias_set ();
4582 }
4583
4584 enum tls_model
4585 decl_tls_model (decl)
4586 tree decl;
4587 {
4588 enum tls_model kind;
4589 tree attr = lookup_attribute ("tls_model", DECL_ATTRIBUTES (decl));
4590 bool is_local;
4591
4592 if (attr)
4593 {
4594 attr = TREE_VALUE (TREE_VALUE (attr));
4595 if (TREE_CODE (attr) != STRING_CST)
4596 abort ();
4597 if (!strcmp (TREE_STRING_POINTER (attr), "local-exec"))
4598 kind = TLS_MODEL_LOCAL_EXEC;
4599 else if (!strcmp (TREE_STRING_POINTER (attr), "initial-exec"))
4600 kind = TLS_MODEL_INITIAL_EXEC;
4601 else if (!strcmp (TREE_STRING_POINTER (attr), "local-dynamic"))
4602 kind = optimize ? TLS_MODEL_LOCAL_DYNAMIC : TLS_MODEL_GLOBAL_DYNAMIC;
4603 else if (!strcmp (TREE_STRING_POINTER (attr), "global-dynamic"))
4604 kind = TLS_MODEL_GLOBAL_DYNAMIC;
4605 else
4606 abort ();
4607 return kind;
4608 }
4609
4610 is_local = (*targetm.binds_local_p) (decl);
4611 if (!flag_pic)
4612 {
4613 if (is_local)
4614 kind = TLS_MODEL_LOCAL_EXEC;
4615 else
4616 kind = TLS_MODEL_INITIAL_EXEC;
4617 }
4618 /* Local dynamic is inefficient when we're not combining the
4619 parts of the address. */
4620 else if (optimize && is_local)
4621 kind = TLS_MODEL_LOCAL_DYNAMIC;
4622 else
4623 kind = TLS_MODEL_GLOBAL_DYNAMIC;
4624 if (kind < flag_tls_default)
4625 kind = flag_tls_default;
4626
4627 return kind;
4628 }
4629
4630 enum symbol_visibility
4631 decl_visibility (decl)
4632 tree decl;
4633 {
4634 tree attr = lookup_attribute ("visibility", DECL_ATTRIBUTES (decl));
4635
4636 if (attr)
4637 {
4638 const char *which = TREE_STRING_POINTER (TREE_VALUE (TREE_VALUE (attr)));
4639
4640 if (strcmp (which, "default") == 0)
4641 return VISIBILITY_DEFAULT;
4642 if (strcmp (which, "internal") == 0)
4643 return VISIBILITY_INTERNAL;
4644 if (strcmp (which, "hidden") == 0)
4645 return VISIBILITY_HIDDEN;
4646 if (strcmp (which, "protected") == 0)
4647 return VISIBILITY_PROTECTED;
4648
4649 abort ();
4650 }
4651
4652 return VISIBILITY_DEFAULT;
4653 }
4654
4655 /* Select a set of attributes for section NAME based on the properties
4656 of DECL and whether or not RELOC indicates that DECL's initializer
4657 might contain runtime relocations.
4658
4659 We make the section read-only and executable for a function decl,
4660 read-only for a const data decl, and writable for a non-const data decl. */
4661
4662 unsigned int
4663 default_section_type_flags (decl, name, reloc)
4664 tree decl;
4665 const char *name;
4666 int reloc;
4667 {
4668 return default_section_type_flags_1 (decl, name, reloc, flag_pic);
4669 }
4670
4671 unsigned int
4672 default_section_type_flags_1 (decl, name, reloc, shlib)
4673 tree decl;
4674 const char *name;
4675 int reloc;
4676 int shlib;
4677 {
4678 unsigned int flags;
4679
4680 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
4681 flags = SECTION_CODE;
4682 else if (decl && decl_readonly_section_1 (decl, reloc, shlib))
4683 flags = 0;
4684 else
4685 flags = SECTION_WRITE;
4686
4687 if (decl && DECL_ONE_ONLY (decl))
4688 flags |= SECTION_LINKONCE;
4689
4690 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl))
4691 flags |= SECTION_TLS | SECTION_WRITE;
4692
4693 if (strcmp (name, ".bss") == 0
4694 || strncmp (name, ".bss.", 5) == 0
4695 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
4696 || strcmp (name, ".sbss") == 0
4697 || strncmp (name, ".sbss.", 6) == 0
4698 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0
4699 || strcmp (name, ".tbss") == 0
4700 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
4701 flags |= SECTION_BSS;
4702
4703 if (strcmp (name, ".tdata") == 0
4704 || strcmp (name, ".tbss") == 0
4705 || strncmp (name, ".gnu.linkonce.td.", 17) == 0
4706 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
4707 flags |= SECTION_TLS;
4708
4709 /* These three sections have special ELF types. They are neither
4710 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
4711 want to print a section type (@progbits or @nobits). If someone
4712 is silly enough to emit code or TLS variables to one of these
4713 sections, then don't handle them specially. */
4714 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
4715 && (strcmp (name, ".init_array") == 0
4716 || strcmp (name, ".fini_array") == 0
4717 || strcmp (name, ".preinit_array") == 0))
4718 flags |= SECTION_NOTYPE;
4719
4720 return flags;
4721 }
4722
4723 /* Output assembly to switch to section NAME with attribute FLAGS.
4724 Four variants for common object file formats. */
4725
4726 void
4727 default_no_named_section (name, flags)
4728 const char *name ATTRIBUTE_UNUSED;
4729 unsigned int flags ATTRIBUTE_UNUSED;
4730 {
4731 /* Some object formats don't support named sections at all. The
4732 front-end should already have flagged this as an error. */
4733 abort ();
4734 }
4735
4736 void
4737 default_elf_asm_named_section (name, flags)
4738 const char *name;
4739 unsigned int flags;
4740 {
4741 char flagchars[10], *f = flagchars;
4742
4743 if (! named_section_first_declaration (name))
4744 {
4745 fprintf (asm_out_file, "\t.section\t%s\n", name);
4746 return;
4747 }
4748
4749 if (!(flags & SECTION_DEBUG))
4750 *f++ = 'a';
4751 if (flags & SECTION_WRITE)
4752 *f++ = 'w';
4753 if (flags & SECTION_CODE)
4754 *f++ = 'x';
4755 if (flags & SECTION_SMALL)
4756 *f++ = 's';
4757 if (flags & SECTION_MERGE)
4758 *f++ = 'M';
4759 if (flags & SECTION_STRINGS)
4760 *f++ = 'S';
4761 if (flags & SECTION_TLS)
4762 *f++ = 'T';
4763 *f = '\0';
4764
4765 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
4766
4767 if (!(flags & SECTION_NOTYPE))
4768 {
4769 const char *type;
4770
4771 if (flags & SECTION_BSS)
4772 type = "nobits";
4773 else
4774 type = "progbits";
4775
4776 fprintf (asm_out_file, ",@%s", type);
4777
4778 if (flags & SECTION_ENTSIZE)
4779 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
4780 }
4781
4782 putc ('\n', asm_out_file);
4783 }
4784
4785 void
4786 default_coff_asm_named_section (name, flags)
4787 const char *name;
4788 unsigned int flags;
4789 {
4790 char flagchars[8], *f = flagchars;
4791
4792 if (flags & SECTION_WRITE)
4793 *f++ = 'w';
4794 if (flags & SECTION_CODE)
4795 *f++ = 'x';
4796 *f = '\0';
4797
4798 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
4799 }
4800
4801 void
4802 default_pe_asm_named_section (name, flags)
4803 const char *name;
4804 unsigned int flags;
4805 {
4806 default_coff_asm_named_section (name, flags);
4807
4808 if (flags & SECTION_LINKONCE)
4809 {
4810 /* Functions may have been compiled at various levels of
4811 optimization so we can't use `same_size' here.
4812 Instead, have the linker pick one. */
4813 fprintf (asm_out_file, "\t.linkonce %s\n",
4814 (flags & SECTION_CODE ? "discard" : "same_size"));
4815 }
4816 }
4817 \f
4818 /* Used for vtable gc in GNU binutils. Record that the pointer at OFFSET
4819 from SYMBOL is used in all classes derived from SYMBOL. */
4820
4821 void
4822 assemble_vtable_entry (symbol, offset)
4823 rtx symbol;
4824 HOST_WIDE_INT offset;
4825 {
4826 fputs ("\t.vtable_entry ", asm_out_file);
4827 output_addr_const (asm_out_file, symbol);
4828 fprintf (asm_out_file, ", " HOST_WIDE_INT_PRINT_DEC "\n", offset);
4829 }
4830
4831 /* Used for vtable gc in GNU binutils. Record the class hierarchy by noting
4832 that the vtable symbol CHILD is derived from the vtable symbol PARENT. */
4833
4834 void
4835 assemble_vtable_inherit (child, parent)
4836 rtx child, parent;
4837 {
4838 fputs ("\t.vtable_inherit ", asm_out_file);
4839 output_addr_const (asm_out_file, child);
4840 fputs (", ", asm_out_file);
4841 output_addr_const (asm_out_file, parent);
4842 fputc ('\n', asm_out_file);
4843 }
4844 \f
4845 /* The lame default section selector. */
4846
4847 void
4848 default_select_section (decl, reloc, align)
4849 tree decl;
4850 int reloc;
4851 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED;
4852 {
4853 bool readonly = false;
4854
4855 if (DECL_P (decl))
4856 {
4857 if (decl_readonly_section (decl, reloc))
4858 readonly = true;
4859 }
4860 else if (TREE_CODE (decl) == CONSTRUCTOR)
4861 {
4862 if (! ((flag_pic && reloc)
4863 || !TREE_READONLY (decl)
4864 || TREE_SIDE_EFFECTS (decl)
4865 || !TREE_CONSTANT (decl)))
4866 readonly = true;
4867 }
4868 else if (TREE_CODE (decl) == STRING_CST)
4869 readonly = !flag_writable_strings;
4870 else if (! (flag_pic && reloc))
4871 readonly = true;
4872
4873 if (readonly)
4874 readonly_data_section ();
4875 else
4876 data_section ();
4877 }
4878
4879 /* A helper function for default_elf_select_section and
4880 default_elf_unique_section. Categorizes the DECL. */
4881
4882 enum section_category
4883 {
4884 SECCAT_TEXT,
4885
4886 SECCAT_RODATA,
4887 SECCAT_RODATA_MERGE_STR,
4888 SECCAT_RODATA_MERGE_STR_INIT,
4889 SECCAT_RODATA_MERGE_CONST,
4890 SECCAT_SRODATA,
4891
4892 SECCAT_DATA,
4893
4894 /* To optimize loading of shared programs, define following subsections
4895 of data section:
4896 _REL Contains data that has relocations, so they get grouped
4897 together and dynamic linker will visit fewer pages in memory.
4898 _RO Contains data that is otherwise read-only. This is useful
4899 with prelinking as most relocations won't be dynamically
4900 linked and thus stay read only.
4901 _LOCAL Marks data containing relocations only to local objects.
4902 These relocations will get fully resolved by prelinking. */
4903 SECCAT_DATA_REL,
4904 SECCAT_DATA_REL_LOCAL,
4905 SECCAT_DATA_REL_RO,
4906 SECCAT_DATA_REL_RO_LOCAL,
4907
4908 SECCAT_SDATA,
4909 SECCAT_TDATA,
4910
4911 SECCAT_BSS,
4912 SECCAT_SBSS,
4913 SECCAT_TBSS
4914 };
4915
4916 static enum section_category
4917 categorize_decl_for_section PARAMS ((tree, int, int));
4918
4919 static enum section_category
4920 categorize_decl_for_section (decl, reloc, shlib)
4921 tree decl;
4922 int reloc;
4923 int shlib;
4924 {
4925 enum section_category ret;
4926
4927 if (TREE_CODE (decl) == FUNCTION_DECL)
4928 return SECCAT_TEXT;
4929 else if (TREE_CODE (decl) == STRING_CST)
4930 {
4931 if (flag_writable_strings)
4932 return SECCAT_DATA;
4933 else
4934 return SECCAT_RODATA_MERGE_STR;
4935 }
4936 else if (TREE_CODE (decl) == VAR_DECL)
4937 {
4938 if (DECL_INITIAL (decl) == NULL
4939 || DECL_INITIAL (decl) == error_mark_node)
4940 ret = SECCAT_BSS;
4941 else if (! TREE_READONLY (decl)
4942 || TREE_SIDE_EFFECTS (decl)
4943 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
4944 {
4945 if (shlib && (reloc & 2))
4946 ret = SECCAT_DATA_REL;
4947 else if (shlib && reloc)
4948 ret = SECCAT_DATA_REL_LOCAL;
4949 else
4950 ret = SECCAT_DATA;
4951 }
4952 else if (shlib && (reloc & 2))
4953 ret = SECCAT_DATA_REL_RO;
4954 else if (shlib && reloc)
4955 ret = SECCAT_DATA_REL_RO_LOCAL;
4956 else if (reloc || flag_merge_constants < 2)
4957 /* C and C++ don't allow different variables to share the same
4958 location. -fmerge-all-constants allows even that (at the
4959 expense of not conforming). */
4960 ret = SECCAT_RODATA;
4961 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
4962 ret = SECCAT_RODATA_MERGE_STR_INIT;
4963 else
4964 ret = SECCAT_RODATA_MERGE_CONST;
4965 }
4966 else if (TREE_CODE (decl) == CONSTRUCTOR)
4967 {
4968 if ((shlib && reloc)
4969 || TREE_SIDE_EFFECTS (decl)
4970 || ! TREE_CONSTANT (decl))
4971 ret = SECCAT_DATA;
4972 else
4973 ret = SECCAT_RODATA;
4974 }
4975 else
4976 ret = SECCAT_RODATA;
4977
4978 /* There are no read-only thread-local sections. */
4979 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl))
4980 {
4981 if (ret == SECCAT_BSS)
4982 ret = SECCAT_TBSS;
4983 else
4984 ret = SECCAT_TDATA;
4985 }
4986
4987 /* If the target uses small data sections, select it. */
4988 else if ((*targetm.in_small_data_p) (decl))
4989 {
4990 if (ret == SECCAT_BSS)
4991 ret = SECCAT_SBSS;
4992 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
4993 ret = SECCAT_SRODATA;
4994 else
4995 ret = SECCAT_SDATA;
4996 }
4997
4998 return ret;
4999 }
5000
5001 bool
5002 decl_readonly_section (decl, reloc)
5003 tree decl;
5004 int reloc;
5005 {
5006 return decl_readonly_section_1 (decl, reloc, flag_pic);
5007 }
5008
5009 bool
5010 decl_readonly_section_1 (decl, reloc, shlib)
5011 tree decl;
5012 int reloc;
5013 int shlib;
5014 {
5015 switch (categorize_decl_for_section (decl, reloc, shlib))
5016 {
5017 case SECCAT_RODATA:
5018 case SECCAT_RODATA_MERGE_STR:
5019 case SECCAT_RODATA_MERGE_STR_INIT:
5020 case SECCAT_RODATA_MERGE_CONST:
5021 case SECCAT_SRODATA:
5022 return true;
5023 break;
5024 default:
5025 return false;
5026 break;
5027 }
5028 }
5029
5030 /* Select a section based on the above categorization. */
5031
5032 void
5033 default_elf_select_section (decl, reloc, align)
5034 tree decl;
5035 int reloc;
5036 unsigned HOST_WIDE_INT align;
5037 {
5038 default_elf_select_section_1 (decl, reloc, align, flag_pic);
5039 }
5040
5041 void
5042 default_elf_select_section_1 (decl, reloc, align, shlib)
5043 tree decl;
5044 int reloc;
5045 unsigned HOST_WIDE_INT align;
5046 int shlib;
5047 {
5048 switch (categorize_decl_for_section (decl, reloc, shlib))
5049 {
5050 case SECCAT_TEXT:
5051 /* We're not supposed to be called on FUNCTION_DECLs. */
5052 abort ();
5053 case SECCAT_RODATA:
5054 readonly_data_section ();
5055 break;
5056 case SECCAT_RODATA_MERGE_STR:
5057 mergeable_string_section (decl, align, 0);
5058 break;
5059 case SECCAT_RODATA_MERGE_STR_INIT:
5060 mergeable_string_section (DECL_INITIAL (decl), align, 0);
5061 break;
5062 case SECCAT_RODATA_MERGE_CONST:
5063 mergeable_constant_section (DECL_MODE (decl), align, 0);
5064 break;
5065 case SECCAT_SRODATA:
5066 named_section (NULL_TREE, ".sdata2", reloc);
5067 break;
5068 case SECCAT_DATA:
5069 data_section ();
5070 break;
5071 case SECCAT_DATA_REL:
5072 named_section (NULL_TREE, ".data.rel", reloc);
5073 break;
5074 case SECCAT_DATA_REL_LOCAL:
5075 named_section (NULL_TREE, ".data.rel.local", reloc);
5076 break;
5077 case SECCAT_DATA_REL_RO:
5078 named_section (NULL_TREE, ".data.rel.ro", reloc);
5079 break;
5080 case SECCAT_DATA_REL_RO_LOCAL:
5081 named_section (NULL_TREE, ".data.rel.ro.local", reloc);
5082 break;
5083 case SECCAT_SDATA:
5084 named_section (NULL_TREE, ".sdata", reloc);
5085 break;
5086 case SECCAT_TDATA:
5087 named_section (NULL_TREE, ".tdata", reloc);
5088 break;
5089 case SECCAT_BSS:
5090 #ifdef BSS_SECTION_ASM_OP
5091 bss_section ();
5092 #else
5093 named_section (NULL_TREE, ".bss", reloc);
5094 #endif
5095 break;
5096 case SECCAT_SBSS:
5097 named_section (NULL_TREE, ".sbss", reloc);
5098 break;
5099 case SECCAT_TBSS:
5100 named_section (NULL_TREE, ".tbss", reloc);
5101 break;
5102 default:
5103 abort ();
5104 }
5105 }
5106
5107 /* Construct a unique section name based on the decl name and the
5108 categorization performed above. */
5109
5110 void
5111 default_unique_section (decl, reloc)
5112 tree decl;
5113 int reloc;
5114 {
5115 default_unique_section_1 (decl, reloc, flag_pic);
5116 }
5117
5118 void
5119 default_unique_section_1 (decl, reloc, shlib)
5120 tree decl;
5121 int reloc;
5122 int shlib;
5123 {
5124 bool one_only = DECL_ONE_ONLY (decl);
5125 const char *prefix, *name;
5126 size_t nlen, plen;
5127 char *string;
5128
5129 switch (categorize_decl_for_section (decl, reloc, shlib))
5130 {
5131 case SECCAT_TEXT:
5132 prefix = one_only ? ".gnu.linkonce.t." : ".text.";
5133 break;
5134 case SECCAT_RODATA:
5135 case SECCAT_RODATA_MERGE_STR:
5136 case SECCAT_RODATA_MERGE_STR_INIT:
5137 case SECCAT_RODATA_MERGE_CONST:
5138 prefix = one_only ? ".gnu.linkonce.r." : ".rodata.";
5139 break;
5140 case SECCAT_SRODATA:
5141 prefix = one_only ? ".gnu.linkonce.s2." : ".sdata2.";
5142 break;
5143 case SECCAT_DATA:
5144 case SECCAT_DATA_REL:
5145 case SECCAT_DATA_REL_LOCAL:
5146 case SECCAT_DATA_REL_RO:
5147 case SECCAT_DATA_REL_RO_LOCAL:
5148 prefix = one_only ? ".gnu.linkonce.d." : ".data.";
5149 break;
5150 case SECCAT_SDATA:
5151 prefix = one_only ? ".gnu.linkonce.s." : ".sdata.";
5152 break;
5153 case SECCAT_BSS:
5154 prefix = one_only ? ".gnu.linkonce.b." : ".bss.";
5155 break;
5156 case SECCAT_SBSS:
5157 prefix = one_only ? ".gnu.linkonce.sb." : ".sbss.";
5158 break;
5159 case SECCAT_TDATA:
5160 prefix = one_only ? ".gnu.linkonce.td." : ".tdata.";
5161 break;
5162 case SECCAT_TBSS:
5163 prefix = one_only ? ".gnu.linkonce.tb." : ".tbss.";
5164 break;
5165 default:
5166 abort ();
5167 }
5168 plen = strlen (prefix);
5169
5170 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5171 name = (* targetm.strip_name_encoding) (name);
5172 nlen = strlen (name);
5173
5174 string = alloca (nlen + plen + 1);
5175 memcpy (string, prefix, plen);
5176 memcpy (string + plen, name, nlen + 1);
5177
5178 DECL_SECTION_NAME (decl) = build_string (nlen + plen, string);
5179 }
5180
5181 void
5182 default_select_rtx_section (mode, x, align)
5183 enum machine_mode mode ATTRIBUTE_UNUSED;
5184 rtx x;
5185 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED;
5186 {
5187 if (flag_pic)
5188 switch (GET_CODE (x))
5189 {
5190 case CONST:
5191 case SYMBOL_REF:
5192 case LABEL_REF:
5193 data_section ();
5194 return;
5195
5196 default:
5197 break;
5198 }
5199
5200 readonly_data_section ();
5201 }
5202
5203 void
5204 default_elf_select_rtx_section (mode, x, align)
5205 enum machine_mode mode;
5206 rtx x;
5207 unsigned HOST_WIDE_INT align;
5208 {
5209 /* ??? Handle small data here somehow. */
5210
5211 if (flag_pic)
5212 switch (GET_CODE (x))
5213 {
5214 case CONST:
5215 case SYMBOL_REF:
5216 named_section (NULL_TREE, ".data.rel.ro", 3);
5217 return;
5218
5219 case LABEL_REF:
5220 named_section (NULL_TREE, ".data.rel.ro.local", 1);
5221 return;
5222
5223 default:
5224 break;
5225 }
5226
5227 mergeable_constant_section (mode, align, 0);
5228 }
5229
5230 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
5231
5232 void
5233 default_encode_section_info (decl, rtl, first)
5234 tree decl;
5235 rtx rtl;
5236 int first ATTRIBUTE_UNUSED;
5237 {
5238 rtx symbol;
5239 int flags;
5240
5241 /* Careful not to prod global register variables. */
5242 if (GET_CODE (rtl) != MEM)
5243 return;
5244 symbol = XEXP (rtl, 0);
5245 if (GET_CODE (symbol) != SYMBOL_REF)
5246 return;
5247
5248 flags = 0;
5249 if (TREE_CODE (decl) == FUNCTION_DECL)
5250 flags |= SYMBOL_FLAG_FUNCTION;
5251 if ((*targetm.binds_local_p) (decl))
5252 flags |= SYMBOL_FLAG_LOCAL;
5253 if ((*targetm.in_small_data_p) (decl))
5254 flags |= SYMBOL_FLAG_SMALL;
5255 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl))
5256 flags |= decl_tls_model (decl) << SYMBOL_FLAG_TLS_SHIFT;
5257 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
5258 being PUBLIC, the thing *must* be defined in this translation unit.
5259 Prevent this buglet from being propagated into rtl code as well. */
5260 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
5261 flags |= SYMBOL_FLAG_EXTERNAL;
5262
5263 SYMBOL_REF_FLAGS (symbol) = flags;
5264 }
5265
5266 /* By default, we do nothing for encode_section_info, so we need not
5267 do anything but discard the '*' marker. */
5268
5269 const char *
5270 default_strip_name_encoding (str)
5271 const char *str;
5272 {
5273 return str + (*str == '*');
5274 }
5275
5276 /* Assume ELF-ish defaults, since that's pretty much the most liberal
5277 wrt cross-module name binding. */
5278
5279 bool
5280 default_binds_local_p (exp)
5281 tree exp;
5282 {
5283 return default_binds_local_p_1 (exp, flag_shlib);
5284 }
5285
5286 bool
5287 default_binds_local_p_1 (exp, shlib)
5288 tree exp;
5289 int shlib;
5290 {
5291 bool local_p;
5292
5293 /* A non-decl is an entry in the constant pool. */
5294 if (!DECL_P (exp))
5295 local_p = true;
5296 /* Static variables are always local. */
5297 else if (! TREE_PUBLIC (exp))
5298 local_p = true;
5299 /* A variable is local if the user tells us so. */
5300 else if (decl_visibility (exp) != VISIBILITY_DEFAULT)
5301 local_p = true;
5302 /* Otherwise, variables defined outside this object may not be local. */
5303 else if (DECL_EXTERNAL (exp))
5304 local_p = false;
5305 /* Linkonce and weak data are never local. */
5306 else if (DECL_ONE_ONLY (exp) || DECL_WEAK (exp))
5307 local_p = false;
5308 /* If PIC, then assume that any global name can be overridden by
5309 symbols resolved from other modules. */
5310 else if (shlib)
5311 local_p = false;
5312 /* Uninitialized COMMON variable may be unified with symbols
5313 resolved from other modules. */
5314 else if (DECL_COMMON (exp)
5315 && (DECL_INITIAL (exp) == NULL
5316 || DECL_INITIAL (exp) == error_mark_node))
5317 local_p = false;
5318 /* Otherwise we're left with initialized (or non-common) global data
5319 which is of necessity defined locally. */
5320 else
5321 local_p = true;
5322
5323 return local_p;
5324 }
5325
5326 /* Determine whether or not a pointer mode is valid. Assume defaults
5327 of ptr_mode or Pmode - can be overridden. */
5328 bool
5329 default_valid_pointer_mode (mode)
5330 enum machine_mode mode;
5331 {
5332 return (mode == ptr_mode || mode == Pmode);
5333 }
5334
5335 /* Default function to output code that will globalize a label. A
5336 target must define GLOBAL_ASM_OP or provide it's own function to
5337 globalize a label. */
5338 #ifdef GLOBAL_ASM_OP
5339 void
5340 default_globalize_label (stream, name)
5341 FILE * stream;
5342 const char *name;
5343 {
5344 fputs (GLOBAL_ASM_OP, stream);
5345 assemble_name (stream, name);
5346 putc ('\n', stream);
5347 }
5348 #endif /* GLOBAL_ASM_OP */
5349
5350 /* This is how to output an internal numbered label where PREFIX is
5351 the class of label and LABELNO is the number within the class. */
5352
5353 void
5354 default_internal_label (stream, prefix, labelno)
5355 FILE *stream;
5356 const char *prefix;
5357 unsigned long labelno;
5358 {
5359 char *const buf = alloca (40 + strlen (prefix));
5360 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
5361 ASM_OUTPUT_LABEL (stream, buf);
5362 }
5363
5364 #include "gt-varasm.h"