lto-cgraph.c (get_alias_symbol): Remove weakref sanity check.
[gcc.git] / gcc / varasm.c
1 /* Output variables, constants and external declarations, for GNU compiler.
2 Copyright (C) 1987-2013 Free Software Foundation, Inc.
3
4 This file is part of GCC.
5
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
10
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
19
20
21 /* This file handles generation of all the assembler code
22 *except* the instructions of a function.
23 This includes declarations of variables and their initial values.
24
25 We also output the assembler code for constants stored in memory
26 and are responsible for combining constants with the same value. */
27
28 #include "config.h"
29 #include "system.h"
30 #include "coretypes.h"
31 #include "tm.h"
32 #include "rtl.h"
33 #include "tree.h"
34 #include "flags.h"
35 #include "function.h"
36 #include "expr.h"
37 #include "hard-reg-set.h"
38 #include "regs.h"
39 #include "output.h"
40 #include "diagnostic-core.h"
41 #include "hashtab.h"
42 #include "ggc.h"
43 #include "langhooks.h"
44 #include "tm_p.h"
45 #include "debug.h"
46 #include "target.h"
47 #include "common/common-target.h"
48 #include "targhooks.h"
49 #include "tree-mudflap.h"
50 #include "cgraph.h"
51 #include "pointer-set.h"
52 #include "asan.h"
53
54 #ifdef XCOFF_DEBUGGING_INFO
55 #include "xcoffout.h" /* Needed for external data
56 declarations for e.g. AIX 4.x. */
57 #endif
58
59 /* The (assembler) name of the first globally-visible object output. */
60 extern GTY(()) const char *first_global_object_name;
61 extern GTY(()) const char *weak_global_object_name;
62
63 const char *first_global_object_name;
64 const char *weak_global_object_name;
65
66 struct addr_const;
67 struct constant_descriptor_rtx;
68 struct rtx_constant_pool;
69
70 #define n_deferred_constants (crtl->varasm.deferred_constants)
71
72 /* Number for making the label on the next
73 constant that is stored in memory. */
74
75 static GTY(()) int const_labelno;
76
77 /* Carry information from ASM_DECLARE_OBJECT_NAME
78 to ASM_FINISH_DECLARE_OBJECT. */
79
80 int size_directive_output;
81
82 /* The last decl for which assemble_variable was called,
83 if it did ASM_DECLARE_OBJECT_NAME.
84 If the last call to assemble_variable didn't do that,
85 this holds 0. */
86
87 tree last_assemble_variable_decl;
88
89 /* The following global variable indicates if the first basic block
90 in a function belongs to the cold partition or not. */
91
92 bool first_function_block_is_cold;
93
94 /* We give all constants their own alias set. Perhaps redundant with
95 MEM_READONLY_P, but pre-dates it. */
96
97 static alias_set_type const_alias_set;
98
99 /* Whether we saw any functions with no_split_stack. */
100
101 static bool saw_no_split_stack;
102
103 static const char *strip_reg_name (const char *);
104 static int contains_pointers_p (tree);
105 #ifdef ASM_OUTPUT_EXTERNAL
106 static bool incorporeal_function_p (tree);
107 #endif
108 static void decode_addr_const (tree, struct addr_const *);
109 static hashval_t const_desc_hash (const void *);
110 static int const_desc_eq (const void *, const void *);
111 static hashval_t const_hash_1 (const tree);
112 static int compare_constant (const tree, const tree);
113 static tree copy_constant (tree);
114 static void output_constant_def_contents (rtx);
115 static void output_addressed_constants (tree);
116 static unsigned HOST_WIDE_INT array_size_for_constructor (tree);
117 static unsigned min_align (unsigned, unsigned);
118 static void globalize_decl (tree);
119 static bool decl_readonly_section_1 (enum section_category);
120 #ifdef BSS_SECTION_ASM_OP
121 #ifdef ASM_OUTPUT_ALIGNED_BSS
122 static void asm_output_aligned_bss (FILE *, tree, const char *,
123 unsigned HOST_WIDE_INT, int)
124 ATTRIBUTE_UNUSED;
125 #endif
126 #endif /* BSS_SECTION_ASM_OP */
127 static void mark_weak (tree);
128 static void output_constant_pool (const char *, tree);
129 \f
130 /* Well-known sections, each one associated with some sort of *_ASM_OP. */
131 section *text_section;
132 section *data_section;
133 section *readonly_data_section;
134 section *sdata_section;
135 section *ctors_section;
136 section *dtors_section;
137 section *bss_section;
138 section *sbss_section;
139
140 /* Various forms of common section. All are guaranteed to be nonnull. */
141 section *tls_comm_section;
142 section *comm_section;
143 section *lcomm_section;
144
145 /* A SECTION_NOSWITCH section used for declaring global BSS variables.
146 May be null. */
147 section *bss_noswitch_section;
148
149 /* The section that holds the main exception table, when known. The section
150 is set either by the target's init_sections hook or by the first call to
151 switch_to_exception_section. */
152 section *exception_section;
153
154 /* The section that holds the DWARF2 frame unwind information, when known.
155 The section is set either by the target's init_sections hook or by the
156 first call to switch_to_eh_frame_section. */
157 section *eh_frame_section;
158
159 /* asm_out_file's current section. This is NULL if no section has yet
160 been selected or if we lose track of what the current section is. */
161 section *in_section;
162
163 /* True if code for the current function is currently being directed
164 at the cold section. */
165 bool in_cold_section_p;
166
167 /* A linked list of all the unnamed sections. */
168 static GTY(()) section *unnamed_sections;
169
170 /* Return a nonzero value if DECL has a section attribute. */
171 #define IN_NAMED_SECTION(DECL) \
172 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \
173 && DECL_SECTION_NAME (DECL) != NULL_TREE)
174
175 /* Hash table of named sections. */
176 static GTY((param_is (section))) htab_t section_htab;
177
178 /* A table of object_blocks, indexed by section. */
179 static GTY((param_is (struct object_block))) htab_t object_block_htab;
180
181 /* The next number to use for internal anchor labels. */
182 static GTY(()) int anchor_labelno;
183
184 /* A pool of constants that can be shared between functions. */
185 static GTY(()) struct rtx_constant_pool *shared_constant_pool;
186
187 /* Helper routines for maintaining section_htab. */
188
189 static int
190 section_entry_eq (const void *p1, const void *p2)
191 {
192 const section *old = (const section *) p1;
193 const char *new_name = (const char *) p2;
194
195 return strcmp (old->named.name, new_name) == 0;
196 }
197
198 static hashval_t
199 section_entry_hash (const void *p)
200 {
201 const section *old = (const section *) p;
202 return htab_hash_string (old->named.name);
203 }
204
205 /* Return a hash value for section SECT. */
206
207 static hashval_t
208 hash_section (section *sect)
209 {
210 if (sect->common.flags & SECTION_NAMED)
211 return htab_hash_string (sect->named.name);
212 return sect->common.flags;
213 }
214
215 /* Helper routines for maintaining object_block_htab. */
216
217 static int
218 object_block_entry_eq (const void *p1, const void *p2)
219 {
220 const struct object_block *old = (const struct object_block *) p1;
221 const section *new_section = (const section *) p2;
222
223 return old->sect == new_section;
224 }
225
226 static hashval_t
227 object_block_entry_hash (const void *p)
228 {
229 const struct object_block *old = (const struct object_block *) p;
230 return hash_section (old->sect);
231 }
232
233 /* Return a new unnamed section with the given fields. */
234
235 section *
236 get_unnamed_section (unsigned int flags, void (*callback) (const void *),
237 const void *data)
238 {
239 section *sect;
240
241 sect = ggc_alloc_section ();
242 sect->unnamed.common.flags = flags | SECTION_UNNAMED;
243 sect->unnamed.callback = callback;
244 sect->unnamed.data = data;
245 sect->unnamed.next = unnamed_sections;
246
247 unnamed_sections = sect;
248 return sect;
249 }
250
251 /* Return a SECTION_NOSWITCH section with the given fields. */
252
253 static section *
254 get_noswitch_section (unsigned int flags, noswitch_section_callback callback)
255 {
256 section *sect;
257
258 sect = ggc_alloc_section ();
259 sect->noswitch.common.flags = flags | SECTION_NOSWITCH;
260 sect->noswitch.callback = callback;
261
262 return sect;
263 }
264
265 /* Return the named section structure associated with NAME. Create
266 a new section with the given fields if no such structure exists. */
267
268 section *
269 get_section (const char *name, unsigned int flags, tree decl)
270 {
271 section *sect, **slot;
272
273 slot = (section **)
274 htab_find_slot_with_hash (section_htab, name,
275 htab_hash_string (name), INSERT);
276 flags |= SECTION_NAMED;
277 if (*slot == NULL)
278 {
279 sect = ggc_alloc_section ();
280 sect->named.common.flags = flags;
281 sect->named.name = ggc_strdup (name);
282 sect->named.decl = decl;
283 *slot = sect;
284 }
285 else
286 {
287 sect = *slot;
288 if ((sect->common.flags & ~SECTION_DECLARED) != flags
289 && ((sect->common.flags | flags) & SECTION_OVERRIDE) == 0)
290 {
291 /* It is fine if one of the section flags is
292 SECTION_WRITE | SECTION_RELRO and the other has none of these
293 flags (i.e. read-only) in named sections and either the
294 section hasn't been declared yet or has been declared as writable.
295 In that case just make sure the resulting flags are
296 SECTION_WRITE | SECTION_RELRO, ie. writable only because of
297 relocations. */
298 if (((sect->common.flags ^ flags) & (SECTION_WRITE | SECTION_RELRO))
299 == (SECTION_WRITE | SECTION_RELRO)
300 && (sect->common.flags
301 & ~(SECTION_DECLARED | SECTION_WRITE | SECTION_RELRO))
302 == (flags & ~(SECTION_WRITE | SECTION_RELRO))
303 && ((sect->common.flags & SECTION_DECLARED) == 0
304 || (sect->common.flags & SECTION_WRITE)))
305 {
306 sect->common.flags |= (SECTION_WRITE | SECTION_RELRO);
307 return sect;
308 }
309 /* Sanity check user variables for flag changes. */
310 if (decl == 0)
311 decl = sect->named.decl;
312 gcc_assert (decl);
313 if (sect->named.decl == NULL)
314 error ("%+D causes a section type conflict", decl);
315 else
316 {
317 error ("%+D causes a section type conflict with %D",
318 decl, sect->named.decl);
319 if (decl != sect->named.decl)
320 inform (DECL_SOURCE_LOCATION (sect->named.decl),
321 "%qD was declared here", sect->named.decl);
322 }
323 /* Make sure we don't error about one section multiple times. */
324 sect->common.flags |= SECTION_OVERRIDE;
325 }
326 }
327 return sect;
328 }
329
330 /* Return true if the current compilation mode benefits from having
331 objects grouped into blocks. */
332
333 static bool
334 use_object_blocks_p (void)
335 {
336 return flag_section_anchors;
337 }
338
339 /* Return the object_block structure for section SECT. Create a new
340 structure if we haven't created one already. Return null if SECT
341 itself is null. */
342
343 static struct object_block *
344 get_block_for_section (section *sect)
345 {
346 struct object_block *block;
347 void **slot;
348
349 if (sect == NULL)
350 return NULL;
351
352 slot = htab_find_slot_with_hash (object_block_htab, sect,
353 hash_section (sect), INSERT);
354 block = (struct object_block *) *slot;
355 if (block == NULL)
356 {
357 block = ggc_alloc_cleared_object_block ();
358 block->sect = sect;
359 *slot = block;
360 }
361 return block;
362 }
363
364 /* Create a symbol with label LABEL and place it at byte offset
365 OFFSET in BLOCK. OFFSET can be negative if the symbol's offset
366 is not yet known. LABEL must be a garbage-collected string. */
367
368 static rtx
369 create_block_symbol (const char *label, struct object_block *block,
370 HOST_WIDE_INT offset)
371 {
372 rtx symbol;
373 unsigned int size;
374
375 /* Create the extended SYMBOL_REF. */
376 size = RTX_HDR_SIZE + sizeof (struct block_symbol);
377 symbol = ggc_alloc_rtx_def (size);
378
379 /* Initialize the normal SYMBOL_REF fields. */
380 memset (symbol, 0, size);
381 PUT_CODE (symbol, SYMBOL_REF);
382 PUT_MODE (symbol, Pmode);
383 XSTR (symbol, 0) = label;
384 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_HAS_BLOCK_INFO;
385
386 /* Initialize the block_symbol stuff. */
387 SYMBOL_REF_BLOCK (symbol) = block;
388 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
389
390 return symbol;
391 }
392
393 /* Return a section with a particular name and with whatever SECTION_*
394 flags section_type_flags deems appropriate. The name of the section
395 is taken from NAME if nonnull, otherwise it is taken from DECL's
396 DECL_SECTION_NAME. DECL is the decl associated with the section
397 (see the section comment for details) and RELOC is as for
398 section_type_flags. */
399
400 section *
401 get_named_section (tree decl, const char *name, int reloc)
402 {
403 unsigned int flags;
404
405 if (name == NULL)
406 {
407 gcc_assert (decl && DECL_P (decl) && DECL_SECTION_NAME (decl));
408 name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
409 }
410
411 flags = targetm.section_type_flags (decl, name, reloc);
412
413 if (decl && !DECL_P (decl))
414 decl = NULL_TREE;
415 return get_section (name, flags, decl);
416 }
417
418 /* If required, set DECL_SECTION_NAME to a unique name. */
419
420 void
421 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
422 int flag_function_or_data_sections)
423 {
424 if (DECL_SECTION_NAME (decl) == NULL_TREE
425 && targetm_common.have_named_sections
426 && (flag_function_or_data_sections
427 || DECL_ONE_ONLY (decl)))
428 {
429 targetm.asm_out.unique_section (decl, reloc);
430 DECL_HAS_IMPLICIT_SECTION_NAME_P (decl) = true;
431 }
432 }
433
434 #ifdef BSS_SECTION_ASM_OP
435
436 #ifdef ASM_OUTPUT_ALIGNED_BSS
437
438 /* Utility function for targets to use in implementing
439 ASM_OUTPUT_ALIGNED_BSS.
440 ??? It is believed that this function will work in most cases so such
441 support is localized here. */
442
443 static void
444 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
445 const char *name, unsigned HOST_WIDE_INT size,
446 int align)
447 {
448 switch_to_section (bss_section);
449 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
450 #ifdef ASM_DECLARE_OBJECT_NAME
451 last_assemble_variable_decl = decl;
452 ASM_DECLARE_OBJECT_NAME (file, name, decl);
453 #else
454 /* Standard thing is just output label for the object. */
455 ASM_OUTPUT_LABEL (file, name);
456 #endif /* ASM_DECLARE_OBJECT_NAME */
457 ASM_OUTPUT_SKIP (file, size ? size : 1);
458 }
459
460 #endif
461
462 #endif /* BSS_SECTION_ASM_OP */
463
464 #ifndef USE_SELECT_SECTION_FOR_FUNCTIONS
465 /* Return the hot section for function DECL. Return text_section for
466 null DECLs. */
467
468 static section *
469 hot_function_section (tree decl)
470 {
471 if (decl != NULL_TREE
472 && DECL_SECTION_NAME (decl) != NULL_TREE
473 && targetm_common.have_named_sections)
474 return get_named_section (decl, NULL, 0);
475 else
476 return text_section;
477 }
478 #endif
479
480 /* Return section for TEXT_SECTION_NAME if DECL or DECL_SECTION_NAME (DECL)
481 is NULL.
482
483 When DECL_SECTION_NAME is non-NULL and it is implicit section and
484 NAMED_SECTION_SUFFIX is non-NULL, then produce section called
485 concatenate the name with NAMED_SECTION_SUFFIX.
486 Otherwise produce "TEXT_SECTION_NAME.IMPLICIT_NAME". */
487
488 section *
489 get_named_text_section (tree decl,
490 const char *text_section_name,
491 const char *named_section_suffix)
492 {
493 if (decl && DECL_SECTION_NAME (decl))
494 {
495 if (named_section_suffix)
496 {
497 tree dsn = DECL_SECTION_NAME (decl);
498 const char *stripped_name;
499 char *name, *buffer;
500
501 name = (char *) alloca (TREE_STRING_LENGTH (dsn) + 1);
502 memcpy (name, TREE_STRING_POINTER (dsn),
503 TREE_STRING_LENGTH (dsn) + 1);
504
505 stripped_name = targetm.strip_name_encoding (name);
506
507 buffer = ACONCAT ((stripped_name, named_section_suffix, NULL));
508 return get_named_section (decl, buffer, 0);
509 }
510 else if (DECL_HAS_IMPLICIT_SECTION_NAME_P (decl))
511 {
512 const char *name;
513
514 /* Do not try to split gnu_linkonce functions. This gets somewhat
515 slipperly. */
516 if (DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP)
517 return NULL;
518 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
519 name = targetm.strip_name_encoding (name);
520 return get_named_section (decl, ACONCAT ((text_section_name, ".",
521 name, NULL)), 0);
522 }
523 else
524 return NULL;
525 }
526 return get_named_section (decl, text_section_name, 0);
527 }
528
529 /* Choose named function section based on its frequency. */
530
531 section *
532 default_function_section (tree decl, enum node_frequency freq,
533 bool startup, bool exit)
534 {
535 #if defined HAVE_LD_EH_GC_SECTIONS && defined HAVE_LD_EH_GC_SECTIONS_BUG
536 /* Old GNU linkers have buggy --gc-section support, which sometimes
537 results in .gcc_except_table* sections being garbage collected. */
538 if (decl
539 && DECL_SECTION_NAME (decl)
540 && DECL_HAS_IMPLICIT_SECTION_NAME_P (decl))
541 return NULL;
542 #endif
543
544 if (!flag_reorder_functions
545 || !targetm_common.have_named_sections)
546 return NULL;
547 /* Startup code should go to startup subsection unless it is
548 unlikely executed (this happens especially with function splitting
549 where we can split away unnecessary parts of static constructors. */
550 if (startup && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
551 return get_named_text_section (decl, ".text.startup", NULL);
552
553 /* Similarly for exit. */
554 if (exit && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
555 return get_named_text_section (decl, ".text.exit", NULL);
556
557 /* Group cold functions together, similarly for hot code. */
558 switch (freq)
559 {
560 case NODE_FREQUENCY_UNLIKELY_EXECUTED:
561 return get_named_text_section (decl, ".text.unlikely", NULL);
562 case NODE_FREQUENCY_HOT:
563 return get_named_text_section (decl, ".text.hot", NULL);
564 default:
565 return NULL;
566 }
567 }
568
569 /* Return the section for function DECL.
570
571 If DECL is NULL_TREE, return the text section. We can be passed
572 NULL_TREE under some circumstances by dbxout.c at least.
573
574 If FORCE_COLD is true, return cold function section ignoring
575 the frequency info of cgraph_node. */
576
577 static section *
578 function_section_1 (tree decl, bool force_cold)
579 {
580 section *section = NULL;
581 enum node_frequency freq = NODE_FREQUENCY_NORMAL;
582 bool startup = false, exit = false;
583
584 if (decl)
585 {
586 struct cgraph_node *node = cgraph_get_node (decl);
587
588 if (node)
589 {
590 freq = node->frequency;
591 startup = node->only_called_at_startup;
592 exit = node->only_called_at_exit;
593 }
594 }
595 if (force_cold)
596 freq = NODE_FREQUENCY_UNLIKELY_EXECUTED;
597
598 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
599 if (decl != NULL_TREE
600 && DECL_SECTION_NAME (decl) != NULL_TREE)
601 {
602 if (targetm.asm_out.function_section)
603 section = targetm.asm_out.function_section (decl, freq,
604 startup, exit);
605 if (section)
606 return section;
607 return get_named_section (decl, NULL, 0);
608 }
609 else
610 return targetm.asm_out.select_section
611 (decl, freq == NODE_FREQUENCY_UNLIKELY_EXECUTED,
612 DECL_ALIGN (decl));
613 #else
614 if (targetm.asm_out.function_section)
615 section = targetm.asm_out.function_section (decl, freq, startup, exit);
616 if (section)
617 return section;
618 return hot_function_section (decl);
619 #endif
620 }
621
622 /* Return the section for function DECL.
623
624 If DECL is NULL_TREE, return the text section. We can be passed
625 NULL_TREE under some circumstances by dbxout.c at least. */
626
627 section *
628 function_section (tree decl)
629 {
630 /* Handle cases where function splitting code decides
631 to put function entry point into unlikely executed section
632 despite the fact that the function itself is not cold
633 (i.e. it is called rarely but contains a hot loop that is
634 better to live in hot subsection for the code locality). */
635 return function_section_1 (decl,
636 first_function_block_is_cold);
637 }
638
639 /* Return the section for the current function, take IN_COLD_SECTION_P
640 into account. */
641
642 section *
643 current_function_section (void)
644 {
645 return function_section_1 (current_function_decl, in_cold_section_p);
646 }
647
648 /* Tell assembler to switch to unlikely-to-be-executed text section. */
649
650 section *
651 unlikely_text_section (void)
652 {
653 return function_section_1 (current_function_decl, true);
654 }
655
656 /* When called within a function context, return true if the function
657 has been assigned a cold text section and if SECT is that section.
658 When called outside a function context, return true if SECT is the
659 default cold section. */
660
661 bool
662 unlikely_text_section_p (section *sect)
663 {
664 return sect == function_section_1 (current_function_decl, true);
665 }
666
667 /* Return the read-only data section associated with function DECL. */
668
669 section *
670 default_function_rodata_section (tree decl)
671 {
672 if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
673 {
674 const char *name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
675
676 if (DECL_ONE_ONLY (decl) && HAVE_COMDAT_GROUP)
677 {
678 const char *dot;
679 size_t len;
680 char* rname;
681
682 dot = strchr (name + 1, '.');
683 if (!dot)
684 dot = name;
685 len = strlen (dot) + 8;
686 rname = (char *) alloca (len);
687
688 strcpy (rname, ".rodata");
689 strcat (rname, dot);
690 return get_section (rname, SECTION_LINKONCE, decl);
691 }
692 /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo. */
693 else if (DECL_ONE_ONLY (decl)
694 && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
695 {
696 size_t len = strlen (name) + 1;
697 char *rname = (char *) alloca (len);
698
699 memcpy (rname, name, len);
700 rname[14] = 'r';
701 return get_section (rname, SECTION_LINKONCE, decl);
702 }
703 /* For .text.foo we want to use .rodata.foo. */
704 else if (flag_function_sections && flag_data_sections
705 && strncmp (name, ".text.", 6) == 0)
706 {
707 size_t len = strlen (name) + 1;
708 char *rname = (char *) alloca (len + 2);
709
710 memcpy (rname, ".rodata", 7);
711 memcpy (rname + 7, name + 5, len - 5);
712 return get_section (rname, 0, decl);
713 }
714 }
715
716 return readonly_data_section;
717 }
718
719 /* Return the read-only data section associated with function DECL
720 for targets where that section should be always the single
721 readonly data section. */
722
723 section *
724 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
725 {
726 return readonly_data_section;
727 }
728
729 /* Return the section to use for string merging. */
730
731 static section *
732 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
733 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
734 unsigned int flags ATTRIBUTE_UNUSED)
735 {
736 HOST_WIDE_INT len;
737
738 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
739 && TREE_CODE (decl) == STRING_CST
740 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
741 && align <= 256
742 && (len = int_size_in_bytes (TREE_TYPE (decl))) > 0
743 && TREE_STRING_LENGTH (decl) >= len)
744 {
745 enum machine_mode mode;
746 unsigned int modesize;
747 const char *str;
748 HOST_WIDE_INT i;
749 int j, unit;
750 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
751 char *name = (char *) alloca (strlen (prefix) + 30);
752
753 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
754 modesize = GET_MODE_BITSIZE (mode);
755 if (modesize >= 8 && modesize <= 256
756 && (modesize & (modesize - 1)) == 0)
757 {
758 if (align < modesize)
759 align = modesize;
760
761 str = TREE_STRING_POINTER (decl);
762 unit = GET_MODE_SIZE (mode);
763
764 /* Check for embedded NUL characters. */
765 for (i = 0; i < len; i += unit)
766 {
767 for (j = 0; j < unit; j++)
768 if (str[i + j] != '\0')
769 break;
770 if (j == unit)
771 break;
772 }
773 if (i == len - unit)
774 {
775 sprintf (name, "%s.str%d.%d", prefix,
776 modesize / 8, (int) (align / 8));
777 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
778 return get_section (name, flags, NULL);
779 }
780 }
781 }
782
783 return readonly_data_section;
784 }
785
786 /* Return the section to use for constant merging. */
787
788 section *
789 mergeable_constant_section (enum machine_mode mode ATTRIBUTE_UNUSED,
790 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
791 unsigned int flags ATTRIBUTE_UNUSED)
792 {
793 unsigned int modesize = GET_MODE_BITSIZE (mode);
794
795 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
796 && mode != VOIDmode
797 && mode != BLKmode
798 && modesize <= align
799 && align >= 8
800 && align <= 256
801 && (align & (align - 1)) == 0)
802 {
803 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
804 char *name = (char *) alloca (strlen (prefix) + 30);
805
806 sprintf (name, "%s.cst%d", prefix, (int) (align / 8));
807 flags |= (align / 8) | SECTION_MERGE;
808 return get_section (name, flags, NULL);
809 }
810 return readonly_data_section;
811 }
812 \f
813 /* Given NAME, a putative register name, discard any customary prefixes. */
814
815 static const char *
816 strip_reg_name (const char *name)
817 {
818 #ifdef REGISTER_PREFIX
819 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
820 name += strlen (REGISTER_PREFIX);
821 #endif
822 if (name[0] == '%' || name[0] == '#')
823 name++;
824 return name;
825 }
826 \f
827 /* The user has asked for a DECL to have a particular name. Set (or
828 change) it in such a way that we don't prefix an underscore to
829 it. */
830 void
831 set_user_assembler_name (tree decl, const char *name)
832 {
833 char *starred = (char *) alloca (strlen (name) + 2);
834 starred[0] = '*';
835 strcpy (starred + 1, name);
836 change_decl_assembler_name (decl, get_identifier (starred));
837 SET_DECL_RTL (decl, NULL_RTX);
838 }
839 \f
840 /* Decode an `asm' spec for a declaration as a register name.
841 Return the register number, or -1 if nothing specified,
842 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
843 or -3 if ASMSPEC is `cc' and is not recognized,
844 or -4 if ASMSPEC is `memory' and is not recognized.
845 Accept an exact spelling or a decimal number.
846 Prefixes such as % are optional. */
847
848 int
849 decode_reg_name_and_count (const char *asmspec, int *pnregs)
850 {
851 /* Presume just one register is clobbered. */
852 *pnregs = 1;
853
854 if (asmspec != 0)
855 {
856 int i;
857
858 /* Get rid of confusing prefixes. */
859 asmspec = strip_reg_name (asmspec);
860
861 /* Allow a decimal number as a "register name". */
862 for (i = strlen (asmspec) - 1; i >= 0; i--)
863 if (! ISDIGIT (asmspec[i]))
864 break;
865 if (asmspec[0] != 0 && i < 0)
866 {
867 i = atoi (asmspec);
868 if (i < FIRST_PSEUDO_REGISTER && i >= 0)
869 return i;
870 else
871 return -2;
872 }
873
874 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
875 if (reg_names[i][0]
876 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
877 return i;
878
879 #ifdef OVERLAPPING_REGISTER_NAMES
880 {
881 static const struct
882 {
883 const char *const name;
884 const int number;
885 const int nregs;
886 } table[] = OVERLAPPING_REGISTER_NAMES;
887
888 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
889 if (table[i].name[0]
890 && ! strcmp (asmspec, table[i].name))
891 {
892 *pnregs = table[i].nregs;
893 return table[i].number;
894 }
895 }
896 #endif /* OVERLAPPING_REGISTER_NAMES */
897
898 #ifdef ADDITIONAL_REGISTER_NAMES
899 {
900 static const struct { const char *const name; const int number; } table[]
901 = ADDITIONAL_REGISTER_NAMES;
902
903 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
904 if (table[i].name[0]
905 && ! strcmp (asmspec, table[i].name))
906 return table[i].number;
907 }
908 #endif /* ADDITIONAL_REGISTER_NAMES */
909
910 if (!strcmp (asmspec, "memory"))
911 return -4;
912
913 if (!strcmp (asmspec, "cc"))
914 return -3;
915
916 return -2;
917 }
918
919 return -1;
920 }
921
922 int
923 decode_reg_name (const char *name)
924 {
925 int count;
926 return decode_reg_name_and_count (name, &count);
927 }
928
929 \f
930 /* Return true if DECL's initializer is suitable for a BSS section. */
931
932 bool
933 bss_initializer_p (const_tree decl)
934 {
935 return (DECL_INITIAL (decl) == NULL
936 || DECL_INITIAL (decl) == error_mark_node
937 || (flag_zero_initialized_in_bss
938 /* Leave constant zeroes in .rodata so they
939 can be shared. */
940 && !TREE_READONLY (decl)
941 && initializer_zerop (DECL_INITIAL (decl))));
942 }
943
944 /* Compute the alignment of variable specified by DECL.
945 DONT_OUTPUT_DATA is from assemble_variable. */
946
947 void
948 align_variable (tree decl, bool dont_output_data)
949 {
950 unsigned int align = DECL_ALIGN (decl);
951
952 /* In the case for initialing an array whose length isn't specified,
953 where we have not yet been able to do the layout,
954 figure out the proper alignment now. */
955 if (dont_output_data && DECL_SIZE (decl) == 0
956 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
957 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
958
959 /* Some object file formats have a maximum alignment which they support.
960 In particular, a.out format supports a maximum alignment of 4. */
961 if (align > MAX_OFILE_ALIGNMENT)
962 {
963 warning (0, "alignment of %q+D is greater than maximum object "
964 "file alignment. Using %d", decl,
965 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
966 align = MAX_OFILE_ALIGNMENT;
967 }
968
969 /* On some machines, it is good to increase alignment sometimes. */
970 if (! DECL_USER_ALIGN (decl))
971 {
972 #ifdef DATA_ALIGNMENT
973 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
974 /* Don't increase alignment too much for TLS variables - TLS space
975 is too precious. */
976 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
977 align = data_align;
978 #endif
979 #ifdef CONSTANT_ALIGNMENT
980 if (DECL_INITIAL (decl) != 0 && DECL_INITIAL (decl) != error_mark_node)
981 {
982 unsigned int const_align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl),
983 align);
984 /* Don't increase alignment too much for TLS variables - TLS space
985 is too precious. */
986 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
987 align = const_align;
988 }
989 #endif
990 }
991
992 /* Reset the alignment in case we have made it tighter, so we can benefit
993 from it in get_pointer_alignment. */
994 DECL_ALIGN (decl) = align;
995 }
996
997 /* Return the section into which the given VAR_DECL or CONST_DECL
998 should be placed. PREFER_NOSWITCH_P is true if a noswitch
999 section should be used wherever possible. */
1000
1001 section *
1002 get_variable_section (tree decl, bool prefer_noswitch_p)
1003 {
1004 addr_space_t as = ADDR_SPACE_GENERIC;
1005 int reloc;
1006
1007 if (TREE_TYPE (decl) != error_mark_node)
1008 as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1009
1010 if (DECL_COMMON (decl))
1011 {
1012 /* If the decl has been given an explicit section name, or it resides
1013 in a non-generic address space, then it isn't common, and shouldn't
1014 be handled as such. */
1015 gcc_assert (DECL_SECTION_NAME (decl) == NULL
1016 && ADDR_SPACE_GENERIC_P (as));
1017 if (DECL_THREAD_LOCAL_P (decl))
1018 return tls_comm_section;
1019 else if (TREE_PUBLIC (decl) && bss_initializer_p (decl))
1020 return comm_section;
1021 }
1022
1023 if (DECL_INITIAL (decl) == error_mark_node)
1024 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1025 else if (DECL_INITIAL (decl))
1026 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1027 else
1028 reloc = 0;
1029
1030 resolve_unique_section (decl, reloc, flag_data_sections);
1031 if (IN_NAMED_SECTION (decl))
1032 return get_named_section (decl, NULL, reloc);
1033
1034 if (ADDR_SPACE_GENERIC_P (as)
1035 && !DECL_THREAD_LOCAL_P (decl)
1036 && !(prefer_noswitch_p && targetm.have_switchable_bss_sections)
1037 && bss_initializer_p (decl))
1038 {
1039 if (!TREE_PUBLIC (decl)
1040 && !(flag_asan && asan_protect_global (decl)))
1041 return lcomm_section;
1042 if (bss_noswitch_section)
1043 return bss_noswitch_section;
1044 }
1045
1046 return targetm.asm_out.select_section (decl, reloc, DECL_ALIGN (decl));
1047 }
1048
1049 /* Return the block into which object_block DECL should be placed. */
1050
1051 static struct object_block *
1052 get_block_for_decl (tree decl)
1053 {
1054 section *sect;
1055
1056 if (TREE_CODE (decl) == VAR_DECL)
1057 {
1058 /* The object must be defined in this translation unit. */
1059 if (DECL_EXTERNAL (decl))
1060 return NULL;
1061
1062 /* There's no point using object blocks for something that is
1063 isolated by definition. */
1064 if (DECL_ONE_ONLY (decl))
1065 return NULL;
1066 }
1067
1068 /* We can only calculate block offsets if the decl has a known
1069 constant size. */
1070 if (DECL_SIZE_UNIT (decl) == NULL)
1071 return NULL;
1072 if (!host_integerp (DECL_SIZE_UNIT (decl), 1))
1073 return NULL;
1074
1075 /* Find out which section should contain DECL. We cannot put it into
1076 an object block if it requires a standalone definition. */
1077 if (TREE_CODE (decl) == VAR_DECL)
1078 align_variable (decl, 0);
1079 sect = get_variable_section (decl, true);
1080 if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
1081 return NULL;
1082
1083 return get_block_for_section (sect);
1084 }
1085
1086 /* Make sure block symbol SYMBOL is in block BLOCK. */
1087
1088 static void
1089 change_symbol_block (rtx symbol, struct object_block *block)
1090 {
1091 if (block != SYMBOL_REF_BLOCK (symbol))
1092 {
1093 gcc_assert (SYMBOL_REF_BLOCK_OFFSET (symbol) < 0);
1094 SYMBOL_REF_BLOCK (symbol) = block;
1095 }
1096 }
1097
1098 /* Return true if it is possible to put DECL in an object_block. */
1099
1100 static bool
1101 use_blocks_for_decl_p (tree decl)
1102 {
1103 /* Only data DECLs can be placed into object blocks. */
1104 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != CONST_DECL)
1105 return false;
1106
1107 /* Detect decls created by dw2_force_const_mem. Such decls are
1108 special because DECL_INITIAL doesn't specify the decl's true value.
1109 dw2_output_indirect_constants will instead call assemble_variable
1110 with dont_output_data set to 1 and then print the contents itself. */
1111 if (DECL_INITIAL (decl) == decl)
1112 return false;
1113
1114 /* If this decl is an alias, then we don't want to emit a
1115 definition. */
1116 if (lookup_attribute ("alias", DECL_ATTRIBUTES (decl)))
1117 return false;
1118
1119 return targetm.use_blocks_for_decl_p (decl);
1120 }
1121
1122 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
1123 have static storage duration. In other words, it should not be an
1124 automatic variable, including PARM_DECLs.
1125
1126 There is, however, one exception: this function handles variables
1127 explicitly placed in a particular register by the user.
1128
1129 This is never called for PARM_DECL nodes. */
1130
1131 void
1132 make_decl_rtl (tree decl)
1133 {
1134 const char *name = 0;
1135 int reg_number;
1136 rtx x;
1137
1138 /* Check that we are not being given an automatic variable. */
1139 gcc_assert (TREE_CODE (decl) != PARM_DECL
1140 && TREE_CODE (decl) != RESULT_DECL);
1141
1142 /* A weak alias has TREE_PUBLIC set but not the other bits. */
1143 gcc_assert (TREE_CODE (decl) != VAR_DECL
1144 || TREE_STATIC (decl)
1145 || TREE_PUBLIC (decl)
1146 || DECL_EXTERNAL (decl)
1147 || DECL_REGISTER (decl));
1148
1149 /* And that we were not given a type or a label. */
1150 gcc_assert (TREE_CODE (decl) != TYPE_DECL
1151 && TREE_CODE (decl) != LABEL_DECL);
1152
1153 /* For a duplicate declaration, we can be called twice on the
1154 same DECL node. Don't discard the RTL already made. */
1155 if (DECL_RTL_SET_P (decl))
1156 {
1157 /* If the old RTL had the wrong mode, fix the mode. */
1158 x = DECL_RTL (decl);
1159 if (GET_MODE (x) != DECL_MODE (decl))
1160 SET_DECL_RTL (decl, adjust_address_nv (x, DECL_MODE (decl), 0));
1161
1162 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1163 return;
1164
1165 /* ??? Another way to do this would be to maintain a hashed
1166 table of such critters. Instead of adding stuff to a DECL
1167 to give certain attributes to it, we could use an external
1168 hash map from DECL to set of attributes. */
1169
1170 /* Let the target reassign the RTL if it wants.
1171 This is necessary, for example, when one machine specific
1172 decl attribute overrides another. */
1173 targetm.encode_section_info (decl, DECL_RTL (decl), false);
1174
1175 /* If the symbol has a SYMBOL_REF_BLOCK field, update it based
1176 on the new decl information. */
1177 if (MEM_P (x)
1178 && GET_CODE (XEXP (x, 0)) == SYMBOL_REF
1179 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (x, 0)))
1180 change_symbol_block (XEXP (x, 0), get_block_for_decl (decl));
1181
1182 /* Make this function static known to the mudflap runtime. */
1183 if (flag_mudflap && TREE_CODE (decl) == VAR_DECL)
1184 mudflap_enqueue_decl (decl);
1185
1186 return;
1187 }
1188
1189 /* If this variable belongs to the global constant pool, retrieve the
1190 pre-computed RTL or recompute it in LTO mode. */
1191 if (TREE_CODE (decl) == VAR_DECL && DECL_IN_CONSTANT_POOL (decl))
1192 {
1193 SET_DECL_RTL (decl, output_constant_def (DECL_INITIAL (decl), 1));
1194 return;
1195 }
1196
1197 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
1198
1199 if (name[0] != '*' && TREE_CODE (decl) != FUNCTION_DECL
1200 && DECL_REGISTER (decl))
1201 {
1202 error ("register name not specified for %q+D", decl);
1203 }
1204 else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1205 {
1206 const char *asmspec = name+1;
1207 enum machine_mode mode = DECL_MODE (decl);
1208 reg_number = decode_reg_name (asmspec);
1209 /* First detect errors in declaring global registers. */
1210 if (reg_number == -1)
1211 error ("register name not specified for %q+D", decl);
1212 else if (reg_number < 0)
1213 error ("invalid register name for %q+D", decl);
1214 else if (mode == BLKmode)
1215 error ("data type of %q+D isn%'t suitable for a register",
1216 decl);
1217 else if (!in_hard_reg_set_p (accessible_reg_set, mode, reg_number))
1218 error ("the register specified for %q+D cannot be accessed"
1219 " by the current target", decl);
1220 else if (!in_hard_reg_set_p (operand_reg_set, mode, reg_number))
1221 error ("the register specified for %q+D is not general enough"
1222 " to be used as a register variable", decl);
1223 else if (!HARD_REGNO_MODE_OK (reg_number, mode))
1224 error ("register specified for %q+D isn%'t suitable for data type",
1225 decl);
1226 /* Now handle properly declared static register variables. */
1227 else
1228 {
1229 int nregs;
1230
1231 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
1232 {
1233 DECL_INITIAL (decl) = 0;
1234 error ("global register variable has initial value");
1235 }
1236 if (TREE_THIS_VOLATILE (decl))
1237 warning (OPT_Wvolatile_register_var,
1238 "optimization may eliminate reads and/or "
1239 "writes to register variables");
1240
1241 /* If the user specified one of the eliminables registers here,
1242 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
1243 confused with that register and be eliminated. This usage is
1244 somewhat suspect... */
1245
1246 SET_DECL_RTL (decl, gen_rtx_raw_REG (mode, reg_number));
1247 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
1248 REG_USERVAR_P (DECL_RTL (decl)) = 1;
1249
1250 if (TREE_STATIC (decl))
1251 {
1252 /* Make this register global, so not usable for anything
1253 else. */
1254 #ifdef ASM_DECLARE_REGISTER_GLOBAL
1255 name = IDENTIFIER_POINTER (DECL_NAME (decl));
1256 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
1257 #endif
1258 nregs = hard_regno_nregs[reg_number][mode];
1259 while (nregs > 0)
1260 globalize_reg (decl, reg_number + --nregs);
1261 }
1262
1263 /* As a register variable, it has no section. */
1264 return;
1265 }
1266 }
1267 /* Now handle ordinary static variables and functions (in memory).
1268 Also handle vars declared register invalidly. */
1269 else if (name[0] == '*')
1270 {
1271 #ifdef REGISTER_PREFIX
1272 if (strlen (REGISTER_PREFIX) != 0)
1273 {
1274 reg_number = decode_reg_name (name);
1275 if (reg_number >= 0 || reg_number == -3)
1276 error ("register name given for non-register variable %q+D", decl);
1277 }
1278 #endif
1279 }
1280
1281 /* Specifying a section attribute on a variable forces it into a
1282 non-.bss section, and thus it cannot be common. */
1283 /* FIXME: In general this code should not be necessary because
1284 visibility pass is doing the same work. But notice_global_symbol
1285 is called early and it needs to make DECL_RTL to get the name.
1286 we take care of recomputing the DECL_RTL after visibility is changed. */
1287 if (TREE_CODE (decl) == VAR_DECL
1288 && DECL_SECTION_NAME (decl) != NULL_TREE
1289 && DECL_INITIAL (decl) == NULL_TREE
1290 && DECL_COMMON (decl))
1291 DECL_COMMON (decl) = 0;
1292
1293 /* Variables can't be both common and weak. */
1294 if (TREE_CODE (decl) == VAR_DECL && DECL_WEAK (decl))
1295 DECL_COMMON (decl) = 0;
1296
1297 if (use_object_blocks_p () && use_blocks_for_decl_p (decl))
1298 x = create_block_symbol (name, get_block_for_decl (decl), -1);
1299 else
1300 {
1301 enum machine_mode address_mode = Pmode;
1302 if (TREE_TYPE (decl) != error_mark_node)
1303 {
1304 addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1305 address_mode = targetm.addr_space.address_mode (as);
1306 }
1307 x = gen_rtx_SYMBOL_REF (address_mode, name);
1308 }
1309 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
1310 SET_SYMBOL_REF_DECL (x, decl);
1311
1312 x = gen_rtx_MEM (DECL_MODE (decl), x);
1313 if (TREE_CODE (decl) != FUNCTION_DECL)
1314 set_mem_attributes (x, decl, 1);
1315 SET_DECL_RTL (decl, x);
1316
1317 /* Optionally set flags or add text to the name to record information
1318 such as that it is a function name.
1319 If the name is changed, the macro ASM_OUTPUT_LABELREF
1320 will have to know how to strip this information. */
1321 targetm.encode_section_info (decl, DECL_RTL (decl), true);
1322
1323 /* Make this function static known to the mudflap runtime. */
1324 if (flag_mudflap && TREE_CODE (decl) == VAR_DECL)
1325 mudflap_enqueue_decl (decl);
1326 }
1327
1328 /* Like make_decl_rtl, but inhibit creation of new alias sets when
1329 calling make_decl_rtl. Also, reset DECL_RTL before returning the
1330 rtl. */
1331
1332 rtx
1333 make_decl_rtl_for_debug (tree decl)
1334 {
1335 unsigned int save_aliasing_flag, save_mudflap_flag;
1336 rtx rtl;
1337
1338 if (DECL_RTL_SET_P (decl))
1339 return DECL_RTL (decl);
1340
1341 /* Kludge alert! Somewhere down the call chain, make_decl_rtl will
1342 call new_alias_set. If running with -fcompare-debug, sometimes
1343 we do not want to create alias sets that will throw the alias
1344 numbers off in the comparison dumps. So... clearing
1345 flag_strict_aliasing will keep new_alias_set() from creating a
1346 new set. It is undesirable to register decl with mudflap
1347 in this case as well. */
1348 save_aliasing_flag = flag_strict_aliasing;
1349 flag_strict_aliasing = 0;
1350 save_mudflap_flag = flag_mudflap;
1351 flag_mudflap = 0;
1352
1353 rtl = DECL_RTL (decl);
1354 /* Reset DECL_RTL back, as various parts of the compiler expects
1355 DECL_RTL set meaning it is actually going to be output. */
1356 SET_DECL_RTL (decl, NULL);
1357
1358 flag_strict_aliasing = save_aliasing_flag;
1359 flag_mudflap = save_mudflap_flag;
1360
1361 return rtl;
1362 }
1363 \f
1364 /* Output a string of literal assembler code
1365 for an `asm' keyword used between functions. */
1366
1367 void
1368 assemble_asm (tree string)
1369 {
1370 const char *p;
1371 app_enable ();
1372
1373 if (TREE_CODE (string) == ADDR_EXPR)
1374 string = TREE_OPERAND (string, 0);
1375
1376 p = TREE_STRING_POINTER (string);
1377 fprintf (asm_out_file, "%s%s\n", p[0] == '\t' ? "" : "\t", p);
1378 }
1379
1380 /* Write the address of the entity given by SYMBOL to SEC. */
1381 void
1382 assemble_addr_to_section (rtx symbol, section *sec)
1383 {
1384 switch_to_section (sec);
1385 assemble_align (POINTER_SIZE);
1386 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1387 }
1388
1389 /* Return the numbered .ctors.N (if CONSTRUCTOR_P) or .dtors.N (if
1390 not) section for PRIORITY. */
1391 section *
1392 get_cdtor_priority_section (int priority, bool constructor_p)
1393 {
1394 char buf[16];
1395
1396 /* ??? This only works reliably with the GNU linker. */
1397 sprintf (buf, "%s.%.5u",
1398 constructor_p ? ".ctors" : ".dtors",
1399 /* Invert the numbering so the linker puts us in the proper
1400 order; constructors are run from right to left, and the
1401 linker sorts in increasing order. */
1402 MAX_INIT_PRIORITY - priority);
1403 return get_section (buf, SECTION_WRITE, NULL);
1404 }
1405
1406 void
1407 default_named_section_asm_out_destructor (rtx symbol, int priority)
1408 {
1409 section *sec;
1410
1411 if (priority != DEFAULT_INIT_PRIORITY)
1412 sec = get_cdtor_priority_section (priority,
1413 /*constructor_p=*/false);
1414 else
1415 sec = get_section (".dtors", SECTION_WRITE, NULL);
1416
1417 assemble_addr_to_section (symbol, sec);
1418 }
1419
1420 #ifdef DTORS_SECTION_ASM_OP
1421 void
1422 default_dtor_section_asm_out_destructor (rtx symbol,
1423 int priority ATTRIBUTE_UNUSED)
1424 {
1425 assemble_addr_to_section (symbol, dtors_section);
1426 }
1427 #endif
1428
1429 void
1430 default_named_section_asm_out_constructor (rtx symbol, int priority)
1431 {
1432 section *sec;
1433
1434 if (priority != DEFAULT_INIT_PRIORITY)
1435 sec = get_cdtor_priority_section (priority,
1436 /*constructor_p=*/true);
1437 else
1438 sec = get_section (".ctors", SECTION_WRITE, NULL);
1439
1440 assemble_addr_to_section (symbol, sec);
1441 }
1442
1443 #ifdef CTORS_SECTION_ASM_OP
1444 void
1445 default_ctor_section_asm_out_constructor (rtx symbol,
1446 int priority ATTRIBUTE_UNUSED)
1447 {
1448 assemble_addr_to_section (symbol, ctors_section);
1449 }
1450 #endif
1451 \f
1452 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1453 a nonzero value if the constant pool should be output before the
1454 start of the function, or a zero value if the pool should output
1455 after the end of the function. The default is to put it before the
1456 start. */
1457
1458 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1459 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1460 #endif
1461
1462 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1463 to be output to assembler.
1464 Set first_global_object_name and weak_global_object_name as appropriate. */
1465
1466 void
1467 notice_global_symbol (tree decl)
1468 {
1469 const char **type = &first_global_object_name;
1470
1471 if (first_global_object_name
1472 || !TREE_PUBLIC (decl)
1473 || DECL_EXTERNAL (decl)
1474 || !DECL_NAME (decl)
1475 || (TREE_CODE (decl) != FUNCTION_DECL
1476 && (TREE_CODE (decl) != VAR_DECL
1477 || (DECL_COMMON (decl)
1478 && (DECL_INITIAL (decl) == 0
1479 || DECL_INITIAL (decl) == error_mark_node))))
1480 || !MEM_P (DECL_RTL (decl)))
1481 return;
1482
1483 /* We win when global object is found, but it is useful to know about weak
1484 symbol as well so we can produce nicer unique names. */
1485 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl) || flag_shlib)
1486 type = &weak_global_object_name;
1487
1488 if (!*type)
1489 {
1490 const char *p;
1491 const char *name;
1492 rtx decl_rtl = DECL_RTL (decl);
1493
1494 p = targetm.strip_name_encoding (XSTR (XEXP (decl_rtl, 0), 0));
1495 name = ggc_strdup (p);
1496
1497 *type = name;
1498 }
1499 }
1500
1501 /* If not using flag_reorder_blocks_and_partition, decide early whether the
1502 current function goes into the cold section, so that targets can use
1503 current_function_section during RTL expansion. DECL describes the
1504 function. */
1505
1506 void
1507 decide_function_section (tree decl)
1508 {
1509 first_function_block_is_cold = false;
1510
1511 if (flag_reorder_blocks_and_partition)
1512 /* We will decide in assemble_start_function. */
1513 return;
1514
1515 if (DECL_SECTION_NAME (decl))
1516 {
1517 struct cgraph_node *node = cgraph_get_node (current_function_decl);
1518 /* Calls to function_section rely on first_function_block_is_cold
1519 being accurate. */
1520 first_function_block_is_cold = (node
1521 && node->frequency
1522 == NODE_FREQUENCY_UNLIKELY_EXECUTED);
1523 }
1524
1525 in_cold_section_p = first_function_block_is_cold;
1526 }
1527
1528 /* Output assembler code for the constant pool of a function and associated
1529 with defining the name of the function. DECL describes the function.
1530 NAME is the function's name. For the constant pool, we use the current
1531 constant pool data. */
1532
1533 void
1534 assemble_start_function (tree decl, const char *fnname)
1535 {
1536 int align;
1537 char tmp_label[100];
1538 bool hot_label_written = false;
1539
1540 if (flag_reorder_blocks_and_partition)
1541 {
1542 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTB", const_labelno);
1543 crtl->subsections.hot_section_label = ggc_strdup (tmp_label);
1544 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDB", const_labelno);
1545 crtl->subsections.cold_section_label = ggc_strdup (tmp_label);
1546 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTE", const_labelno);
1547 crtl->subsections.hot_section_end_label = ggc_strdup (tmp_label);
1548 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDE", const_labelno);
1549 crtl->subsections.cold_section_end_label = ggc_strdup (tmp_label);
1550 const_labelno++;
1551 }
1552 else
1553 {
1554 crtl->subsections.hot_section_label = NULL;
1555 crtl->subsections.cold_section_label = NULL;
1556 crtl->subsections.hot_section_end_label = NULL;
1557 crtl->subsections.cold_section_end_label = NULL;
1558 }
1559
1560 /* The following code does not need preprocessing in the assembler. */
1561
1562 app_disable ();
1563
1564 if (CONSTANT_POOL_BEFORE_FUNCTION)
1565 output_constant_pool (fnname, decl);
1566
1567 /* Make sure the not and cold text (code) sections are properly
1568 aligned. This is necessary here in the case where the function
1569 has both hot and cold sections, because we don't want to re-set
1570 the alignment when the section switch happens mid-function. */
1571
1572 if (flag_reorder_blocks_and_partition)
1573 {
1574 first_function_block_is_cold = false;
1575
1576 switch_to_section (unlikely_text_section ());
1577 assemble_align (DECL_ALIGN (decl));
1578 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_label);
1579
1580 /* When the function starts with a cold section, we need to explicitly
1581 align the hot section and write out the hot section label.
1582 But if the current function is a thunk, we do not have a CFG. */
1583 if (!cfun->is_thunk
1584 && BB_PARTITION (ENTRY_BLOCK_PTR->next_bb) == BB_COLD_PARTITION)
1585 {
1586 switch_to_section (text_section);
1587 assemble_align (DECL_ALIGN (decl));
1588 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1589 hot_label_written = true;
1590 first_function_block_is_cold = true;
1591 }
1592 in_cold_section_p = first_function_block_is_cold;
1593 }
1594
1595
1596 /* Switch to the correct text section for the start of the function. */
1597
1598 switch_to_section (function_section (decl));
1599 if (flag_reorder_blocks_and_partition
1600 && !hot_label_written)
1601 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1602
1603 /* Tell assembler to move to target machine's alignment for functions. */
1604 align = floor_log2 (DECL_ALIGN (decl) / BITS_PER_UNIT);
1605 if (align > 0)
1606 {
1607 ASM_OUTPUT_ALIGN (asm_out_file, align);
1608 }
1609
1610 /* Handle a user-specified function alignment.
1611 Note that we still need to align to DECL_ALIGN, as above,
1612 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1613 if (! DECL_USER_ALIGN (decl)
1614 && align_functions_log > align
1615 && optimize_function_for_speed_p (cfun))
1616 {
1617 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1618 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1619 align_functions_log, align_functions - 1);
1620 #else
1621 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1622 #endif
1623 }
1624
1625 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1626 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1627 #endif
1628
1629 if (!DECL_IGNORED_P (decl))
1630 (*debug_hooks->begin_function) (decl);
1631
1632 /* Make function name accessible from other files, if appropriate. */
1633
1634 if (TREE_PUBLIC (decl))
1635 {
1636 notice_global_symbol (decl);
1637
1638 globalize_decl (decl);
1639
1640 maybe_assemble_visibility (decl);
1641 }
1642
1643 if (DECL_PRESERVE_P (decl))
1644 targetm.asm_out.mark_decl_preserved (fnname);
1645
1646 /* Do any machine/system dependent processing of the function name. */
1647 #ifdef ASM_DECLARE_FUNCTION_NAME
1648 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1649 #else
1650 /* Standard thing is just output label for the function. */
1651 ASM_OUTPUT_FUNCTION_LABEL (asm_out_file, fnname, current_function_decl);
1652 #endif /* ASM_DECLARE_FUNCTION_NAME */
1653
1654 if (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (decl)))
1655 saw_no_split_stack = true;
1656 }
1657
1658 /* Output assembler code associated with defining the size of the
1659 function. DECL describes the function. NAME is the function's name. */
1660
1661 void
1662 assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED)
1663 {
1664 #ifdef ASM_DECLARE_FUNCTION_SIZE
1665 /* We could have switched section in the middle of the function. */
1666 if (flag_reorder_blocks_and_partition)
1667 switch_to_section (function_section (decl));
1668 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1669 #endif
1670 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1671 {
1672 output_constant_pool (fnname, decl);
1673 switch_to_section (function_section (decl)); /* need to switch back */
1674 }
1675 /* Output labels for end of hot/cold text sections (to be used by
1676 debug info.) */
1677 if (flag_reorder_blocks_and_partition)
1678 {
1679 section *save_text_section;
1680
1681 save_text_section = in_section;
1682 switch_to_section (unlikely_text_section ());
1683 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label);
1684 if (first_function_block_is_cold)
1685 switch_to_section (text_section);
1686 else
1687 switch_to_section (function_section (decl));
1688 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label);
1689 switch_to_section (save_text_section);
1690 }
1691 }
1692 \f
1693 /* Assemble code to leave SIZE bytes of zeros. */
1694
1695 void
1696 assemble_zeros (unsigned HOST_WIDE_INT size)
1697 {
1698 /* Do no output if -fsyntax-only. */
1699 if (flag_syntax_only)
1700 return;
1701
1702 #ifdef ASM_NO_SKIP_IN_TEXT
1703 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1704 so we must output 0s explicitly in the text section. */
1705 if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0)
1706 {
1707 unsigned HOST_WIDE_INT i;
1708 for (i = 0; i < size; i++)
1709 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1710 }
1711 else
1712 #endif
1713 if (size > 0)
1714 ASM_OUTPUT_SKIP (asm_out_file, size);
1715 }
1716
1717 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1718
1719 void
1720 assemble_align (int align)
1721 {
1722 if (align > BITS_PER_UNIT)
1723 {
1724 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1725 }
1726 }
1727
1728 /* Assemble a string constant with the specified C string as contents. */
1729
1730 void
1731 assemble_string (const char *p, int size)
1732 {
1733 int pos = 0;
1734 int maximum = 2000;
1735
1736 /* If the string is very long, split it up. */
1737
1738 while (pos < size)
1739 {
1740 int thissize = size - pos;
1741 if (thissize > maximum)
1742 thissize = maximum;
1743
1744 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1745
1746 pos += thissize;
1747 p += thissize;
1748 }
1749 }
1750
1751 \f
1752 /* A noswitch_section_callback for lcomm_section. */
1753
1754 static bool
1755 emit_local (tree decl ATTRIBUTE_UNUSED,
1756 const char *name ATTRIBUTE_UNUSED,
1757 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1758 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1759 {
1760 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1761 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name,
1762 size, DECL_ALIGN (decl));
1763 return true;
1764 #elif defined ASM_OUTPUT_ALIGNED_LOCAL
1765 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, DECL_ALIGN (decl));
1766 return true;
1767 #else
1768 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1769 return false;
1770 #endif
1771 }
1772
1773 /* A noswitch_section_callback for bss_noswitch_section. */
1774
1775 #if defined ASM_OUTPUT_ALIGNED_BSS
1776 static bool
1777 emit_bss (tree decl ATTRIBUTE_UNUSED,
1778 const char *name ATTRIBUTE_UNUSED,
1779 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1780 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1781 {
1782 #if defined ASM_OUTPUT_ALIGNED_BSS
1783 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size, DECL_ALIGN (decl));
1784 return true;
1785 #endif
1786 }
1787 #endif
1788
1789 /* A noswitch_section_callback for comm_section. */
1790
1791 static bool
1792 emit_common (tree decl ATTRIBUTE_UNUSED,
1793 const char *name ATTRIBUTE_UNUSED,
1794 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1795 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1796 {
1797 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1798 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name,
1799 size, DECL_ALIGN (decl));
1800 return true;
1801 #elif defined ASM_OUTPUT_ALIGNED_COMMON
1802 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size, DECL_ALIGN (decl));
1803 return true;
1804 #else
1805 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
1806 return false;
1807 #endif
1808 }
1809
1810 /* A noswitch_section_callback for tls_comm_section. */
1811
1812 static bool
1813 emit_tls_common (tree decl ATTRIBUTE_UNUSED,
1814 const char *name ATTRIBUTE_UNUSED,
1815 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1816 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1817 {
1818 #ifdef ASM_OUTPUT_TLS_COMMON
1819 ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size);
1820 return true;
1821 #else
1822 sorry ("thread-local COMMON data not implemented");
1823 return true;
1824 #endif
1825 }
1826
1827 /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT.
1828 NAME is the name of DECL's SYMBOL_REF. */
1829
1830 static void
1831 assemble_noswitch_variable (tree decl, const char *name, section *sect)
1832 {
1833 unsigned HOST_WIDE_INT size, rounded;
1834
1835 size = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
1836 rounded = size;
1837
1838 if (flag_asan && asan_protect_global (decl))
1839 size += asan_red_zone_size (size);
1840
1841 /* Don't allocate zero bytes of common,
1842 since that means "undefined external" in the linker. */
1843 if (size == 0)
1844 rounded = 1;
1845
1846 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1847 so that each uninitialized object starts on such a boundary. */
1848 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
1849 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1850 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1851
1852 if (!sect->noswitch.callback (decl, name, size, rounded)
1853 && (unsigned HOST_WIDE_INT) DECL_ALIGN_UNIT (decl) > rounded)
1854 warning (0, "requested alignment for %q+D is greater than "
1855 "implemented alignment of %wu", decl, rounded);
1856 }
1857
1858 /* A subroutine of assemble_variable. Output the label and contents of
1859 DECL, whose address is a SYMBOL_REF with name NAME. DONT_OUTPUT_DATA
1860 is as for assemble_variable. */
1861
1862 static void
1863 assemble_variable_contents (tree decl, const char *name,
1864 bool dont_output_data)
1865 {
1866 /* Do any machine/system dependent processing of the object. */
1867 #ifdef ASM_DECLARE_OBJECT_NAME
1868 last_assemble_variable_decl = decl;
1869 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
1870 #else
1871 /* Standard thing is just output label for the object. */
1872 ASM_OUTPUT_LABEL (asm_out_file, name);
1873 #endif /* ASM_DECLARE_OBJECT_NAME */
1874
1875 if (!dont_output_data)
1876 {
1877 if (DECL_INITIAL (decl)
1878 && DECL_INITIAL (decl) != error_mark_node
1879 && !initializer_zerop (DECL_INITIAL (decl)))
1880 /* Output the actual data. */
1881 output_constant (DECL_INITIAL (decl),
1882 tree_low_cst (DECL_SIZE_UNIT (decl), 1),
1883 DECL_ALIGN (decl));
1884 else
1885 /* Leave space for it. */
1886 assemble_zeros (tree_low_cst (DECL_SIZE_UNIT (decl), 1));
1887 }
1888 }
1889
1890 /* Assemble everything that is needed for a variable or function declaration.
1891 Not used for automatic variables, and not used for function definitions.
1892 Should not be called for variables of incomplete structure type.
1893
1894 TOP_LEVEL is nonzero if this variable has file scope.
1895 AT_END is nonzero if this is the special handling, at end of compilation,
1896 to define things that have had only tentative definitions.
1897 DONT_OUTPUT_DATA if nonzero means don't actually output the
1898 initial value (that will be done by the caller). */
1899
1900 void
1901 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
1902 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
1903 {
1904 const char *name;
1905 rtx decl_rtl, symbol;
1906 section *sect;
1907 bool asan_protected = false;
1908
1909 /* This function is supposed to handle VARIABLES. Ensure we have one. */
1910 gcc_assert (TREE_CODE (decl) == VAR_DECL);
1911
1912 /* Emulated TLS had better not get this far. */
1913 gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl));
1914
1915 last_assemble_variable_decl = 0;
1916
1917 /* Normally no need to say anything here for external references,
1918 since assemble_external is called by the language-specific code
1919 when a declaration is first seen. */
1920
1921 if (DECL_EXTERNAL (decl))
1922 return;
1923
1924 /* Do nothing for global register variables. */
1925 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
1926 {
1927 TREE_ASM_WRITTEN (decl) = 1;
1928 return;
1929 }
1930
1931 /* If type was incomplete when the variable was declared,
1932 see if it is complete now. */
1933
1934 if (DECL_SIZE (decl) == 0)
1935 layout_decl (decl, 0);
1936
1937 /* Still incomplete => don't allocate it; treat the tentative defn
1938 (which is what it must have been) as an `extern' reference. */
1939
1940 if (!dont_output_data && DECL_SIZE (decl) == 0)
1941 {
1942 error ("storage size of %q+D isn%'t known", decl);
1943 TREE_ASM_WRITTEN (decl) = 1;
1944 return;
1945 }
1946
1947 /* The first declaration of a variable that comes through this function
1948 decides whether it is global (in C, has external linkage)
1949 or local (in C, has internal linkage). So do nothing more
1950 if this function has already run. */
1951
1952 if (TREE_ASM_WRITTEN (decl))
1953 return;
1954
1955 /* Make sure targetm.encode_section_info is invoked before we set
1956 ASM_WRITTEN. */
1957 decl_rtl = DECL_RTL (decl);
1958
1959 TREE_ASM_WRITTEN (decl) = 1;
1960
1961 /* Do no output if -fsyntax-only. */
1962 if (flag_syntax_only)
1963 return;
1964
1965 if (! dont_output_data
1966 && ! valid_constant_size_p (DECL_SIZE_UNIT (decl)))
1967 {
1968 error ("size of variable %q+D is too large", decl);
1969 return;
1970 }
1971
1972 gcc_assert (MEM_P (decl_rtl));
1973 gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF);
1974 symbol = XEXP (decl_rtl, 0);
1975
1976 /* If this symbol belongs to the tree constant pool, output the constant
1977 if it hasn't already been written. */
1978 if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
1979 {
1980 tree decl = SYMBOL_REF_DECL (symbol);
1981 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
1982 output_constant_def_contents (symbol);
1983 return;
1984 }
1985
1986 app_disable ();
1987
1988 name = XSTR (symbol, 0);
1989 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
1990 notice_global_symbol (decl);
1991
1992 /* Compute the alignment of this data. */
1993
1994 align_variable (decl, dont_output_data);
1995
1996 if (flag_asan
1997 && asan_protect_global (decl))
1998 {
1999 asan_protected = true;
2000 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
2001 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
2002 }
2003
2004 set_mem_align (decl_rtl, DECL_ALIGN (decl));
2005
2006 if (TREE_PUBLIC (decl))
2007 maybe_assemble_visibility (decl);
2008
2009 if (DECL_PRESERVE_P (decl))
2010 targetm.asm_out.mark_decl_preserved (name);
2011
2012 /* First make the assembler name(s) global if appropriate. */
2013 sect = get_variable_section (decl, false);
2014 if (TREE_PUBLIC (decl)
2015 && (sect->common.flags & SECTION_COMMON) == 0)
2016 globalize_decl (decl);
2017
2018 /* Output any data that we will need to use the address of. */
2019 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
2020 output_addressed_constants (DECL_INITIAL (decl));
2021
2022 /* dbxout.c needs to know this. */
2023 if (sect && (sect->common.flags & SECTION_CODE) != 0)
2024 DECL_IN_TEXT_SECTION (decl) = 1;
2025
2026 /* If the decl is part of an object_block, make sure that the decl
2027 has been positioned within its block, but do not write out its
2028 definition yet. output_object_blocks will do that later. */
2029 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
2030 {
2031 gcc_assert (!dont_output_data);
2032 place_block_symbol (symbol);
2033 }
2034 else if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
2035 assemble_noswitch_variable (decl, name, sect);
2036 else
2037 {
2038 switch_to_section (sect);
2039 if (DECL_ALIGN (decl) > BITS_PER_UNIT)
2040 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (DECL_ALIGN_UNIT (decl)));
2041 assemble_variable_contents (decl, name, dont_output_data);
2042 if (asan_protected)
2043 {
2044 unsigned HOST_WIDE_INT int size
2045 = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
2046 assemble_zeros (asan_red_zone_size (size));
2047 }
2048 }
2049 }
2050
2051 /* Return 1 if type TYPE contains any pointers. */
2052
2053 static int
2054 contains_pointers_p (tree type)
2055 {
2056 switch (TREE_CODE (type))
2057 {
2058 case POINTER_TYPE:
2059 case REFERENCE_TYPE:
2060 /* I'm not sure whether OFFSET_TYPE needs this treatment,
2061 so I'll play safe and return 1. */
2062 case OFFSET_TYPE:
2063 return 1;
2064
2065 case RECORD_TYPE:
2066 case UNION_TYPE:
2067 case QUAL_UNION_TYPE:
2068 {
2069 tree fields;
2070 /* For a type that has fields, see if the fields have pointers. */
2071 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2072 if (TREE_CODE (fields) == FIELD_DECL
2073 && contains_pointers_p (TREE_TYPE (fields)))
2074 return 1;
2075 return 0;
2076 }
2077
2078 case ARRAY_TYPE:
2079 /* An array type contains pointers if its element type does. */
2080 return contains_pointers_p (TREE_TYPE (type));
2081
2082 default:
2083 return 0;
2084 }
2085 }
2086
2087 /* We delay assemble_external processing until
2088 the compilation unit is finalized. This is the best we can do for
2089 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2090 it all the way to final. See PR 17982 for further discussion. */
2091 static GTY(()) tree pending_assemble_externals;
2092
2093 #ifdef ASM_OUTPUT_EXTERNAL
2094 /* Some targets delay some output to final using TARGET_ASM_FILE_END.
2095 As a result, assemble_external can be called after the list of externals
2096 is processed and the pointer set destroyed. */
2097 static bool pending_assemble_externals_processed;
2098
2099 /* Avoid O(external_decls**2) lookups in the pending_assemble_externals
2100 TREE_LIST in assemble_external. */
2101 static struct pointer_set_t *pending_assemble_externals_set;
2102
2103 /* True if DECL is a function decl for which no out-of-line copy exists.
2104 It is assumed that DECL's assembler name has been set. */
2105
2106 static bool
2107 incorporeal_function_p (tree decl)
2108 {
2109 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
2110 {
2111 const char *name;
2112
2113 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2114 && (DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA
2115 || DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA_WITH_ALIGN))
2116 return true;
2117
2118 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2119 /* Atomic or sync builtins which have survived this far will be
2120 resolved externally and therefore are not incorporeal. */
2121 if (strncmp (name, "__builtin_", 10) == 0)
2122 return true;
2123 }
2124 return false;
2125 }
2126
2127 /* Actually do the tests to determine if this is necessary, and invoke
2128 ASM_OUTPUT_EXTERNAL. */
2129 static void
2130 assemble_external_real (tree decl)
2131 {
2132 rtx rtl = DECL_RTL (decl);
2133
2134 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2135 && !SYMBOL_REF_USED (XEXP (rtl, 0))
2136 && !incorporeal_function_p (decl))
2137 {
2138 /* Some systems do require some output. */
2139 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2140 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2141 }
2142 }
2143 #endif
2144
2145 void
2146 process_pending_assemble_externals (void)
2147 {
2148 #ifdef ASM_OUTPUT_EXTERNAL
2149 tree list;
2150 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2151 assemble_external_real (TREE_VALUE (list));
2152
2153 pending_assemble_externals = 0;
2154 pending_assemble_externals_processed = true;
2155 pointer_set_destroy (pending_assemble_externals_set);
2156 #endif
2157 }
2158
2159 /* This TREE_LIST contains any weak symbol declarations waiting
2160 to be emitted. */
2161 static GTY(()) tree weak_decls;
2162
2163 /* Output something to declare an external symbol to the assembler,
2164 and qualifiers such as weakness. (Most assemblers don't need
2165 extern declaration, so we normally output nothing.) Do nothing if
2166 DECL is not external. */
2167
2168 void
2169 assemble_external (tree decl ATTRIBUTE_UNUSED)
2170 {
2171 /* Make sure that the ASM_OUT_FILE is open.
2172 If it's not, we should not be calling this function. */
2173 gcc_assert (asm_out_file);
2174
2175 /* In a perfect world, the following condition would be true.
2176 Sadly, the Java and Go front ends emit assembly *from the front end*,
2177 bypassing the call graph. See PR52739. Fix before GCC 4.8. */
2178 #if 0
2179 /* This function should only be called if we are expanding, or have
2180 expanded, to RTL.
2181 Ideally, only final.c would be calling this function, but it is
2182 not clear whether that would break things somehow. See PR 17982
2183 for further discussion. */
2184 gcc_assert (cgraph_state == CGRAPH_STATE_EXPANSION
2185 || cgraph_state == CGRAPH_STATE_FINISHED);
2186 #endif
2187
2188 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2189 return;
2190
2191 /* We want to output annotation for weak and external symbols at
2192 very last to check if they are references or not. */
2193
2194 if (TARGET_SUPPORTS_WEAK
2195 && DECL_WEAK (decl)
2196 /* TREE_STATIC is a weird and abused creature which is not
2197 generally the right test for whether an entity has been
2198 locally emitted, inlined or otherwise not-really-extern, but
2199 for declarations that can be weak, it happens to be
2200 match. */
2201 && !TREE_STATIC (decl)
2202 && lookup_attribute ("weak", DECL_ATTRIBUTES (decl))
2203 && value_member (decl, weak_decls) == NULL_TREE)
2204 weak_decls = tree_cons (NULL, decl, weak_decls);
2205
2206 #ifdef ASM_OUTPUT_EXTERNAL
2207 if (pending_assemble_externals_processed)
2208 {
2209 assemble_external_real (decl);
2210 return;
2211 }
2212
2213 if (! pointer_set_insert (pending_assemble_externals_set, decl))
2214 pending_assemble_externals = tree_cons (NULL, decl,
2215 pending_assemble_externals);
2216 #endif
2217 }
2218
2219 /* Similar, for calling a library function FUN. */
2220
2221 void
2222 assemble_external_libcall (rtx fun)
2223 {
2224 /* Declare library function name external when first used, if nec. */
2225 if (! SYMBOL_REF_USED (fun))
2226 {
2227 SYMBOL_REF_USED (fun) = 1;
2228 targetm.asm_out.external_libcall (fun);
2229 }
2230 }
2231
2232 /* Assemble a label named NAME. */
2233
2234 void
2235 assemble_label (FILE *file, const char *name)
2236 {
2237 ASM_OUTPUT_LABEL (file, name);
2238 }
2239
2240 /* Set the symbol_referenced flag for ID. */
2241 void
2242 mark_referenced (tree id)
2243 {
2244 TREE_SYMBOL_REFERENCED (id) = 1;
2245 }
2246
2247 /* Set the symbol_referenced flag for DECL and notify callgraph. */
2248 void
2249 mark_decl_referenced (tree decl)
2250 {
2251 if (TREE_CODE (decl) == FUNCTION_DECL)
2252 {
2253 /* Extern inline functions don't become needed when referenced.
2254 If we know a method will be emitted in other TU and no new
2255 functions can be marked reachable, just use the external
2256 definition. */
2257 struct cgraph_node *node = cgraph_get_create_node (decl);
2258 if (!DECL_EXTERNAL (decl)
2259 && !node->symbol.definition)
2260 cgraph_mark_force_output_node (node);
2261 }
2262 else if (TREE_CODE (decl) == VAR_DECL)
2263 {
2264 struct varpool_node *node = varpool_node_for_decl (decl);
2265 /* C++ frontend use mark_decl_references to force COMDAT variables
2266 to be output that might appear dead otherwise. */
2267 node->symbol.force_output = true;
2268 }
2269 /* else do nothing - we can get various sorts of CST nodes here,
2270 which do not need to be marked. */
2271 }
2272
2273
2274 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS
2275 until we find an identifier that is not itself a transparent alias.
2276 Modify the alias passed to it by reference (and all aliases on the
2277 way to the ultimate target), such that they do not have to be
2278 followed again, and return the ultimate target of the alias
2279 chain. */
2280
2281 static inline tree
2282 ultimate_transparent_alias_target (tree *alias)
2283 {
2284 tree target = *alias;
2285
2286 if (IDENTIFIER_TRANSPARENT_ALIAS (target))
2287 {
2288 gcc_assert (TREE_CHAIN (target));
2289 target = ultimate_transparent_alias_target (&TREE_CHAIN (target));
2290 gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target)
2291 && ! TREE_CHAIN (target));
2292 *alias = target;
2293 }
2294
2295 return target;
2296 }
2297
2298 /* Output to FILE (an assembly file) a reference to NAME. If NAME
2299 starts with a *, the rest of NAME is output verbatim. Otherwise
2300 NAME is transformed in a target-specific way (usually by the
2301 addition of an underscore). */
2302
2303 void
2304 assemble_name_raw (FILE *file, const char *name)
2305 {
2306 if (name[0] == '*')
2307 fputs (&name[1], file);
2308 else
2309 ASM_OUTPUT_LABELREF (file, name);
2310 }
2311
2312 /* Like assemble_name_raw, but should be used when NAME might refer to
2313 an entity that is also represented as a tree (like a function or
2314 variable). If NAME does refer to such an entity, that entity will
2315 be marked as referenced. */
2316
2317 void
2318 assemble_name (FILE *file, const char *name)
2319 {
2320 const char *real_name;
2321 tree id;
2322
2323 real_name = targetm.strip_name_encoding (name);
2324
2325 id = maybe_get_identifier (real_name);
2326 if (id)
2327 {
2328 tree id_orig = id;
2329
2330 mark_referenced (id);
2331 ultimate_transparent_alias_target (&id);
2332 if (id != id_orig)
2333 name = IDENTIFIER_POINTER (id);
2334 gcc_assert (! TREE_CHAIN (id));
2335 }
2336
2337 assemble_name_raw (file, name);
2338 }
2339
2340 /* Allocate SIZE bytes writable static space with a gensym name
2341 and return an RTX to refer to its address. */
2342
2343 rtx
2344 assemble_static_space (unsigned HOST_WIDE_INT size)
2345 {
2346 char name[12];
2347 const char *namestring;
2348 rtx x;
2349
2350 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2351 ++const_labelno;
2352 namestring = ggc_strdup (name);
2353
2354 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2355 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2356
2357 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2358 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2359 BIGGEST_ALIGNMENT);
2360 #else
2361 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2362 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2363 #else
2364 {
2365 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2366 so that each uninitialized object starts on such a boundary. */
2367 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2368 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2369 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2370 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2371 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2372 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2373 }
2374 #endif
2375 #endif
2376 return x;
2377 }
2378
2379 /* Assemble the static constant template for function entry trampolines.
2380 This is done at most once per compilation.
2381 Returns an RTX for the address of the template. */
2382
2383 static GTY(()) rtx initial_trampoline;
2384
2385 rtx
2386 assemble_trampoline_template (void)
2387 {
2388 char label[256];
2389 const char *name;
2390 int align;
2391 rtx symbol;
2392
2393 gcc_assert (targetm.asm_out.trampoline_template != NULL);
2394
2395 if (initial_trampoline)
2396 return initial_trampoline;
2397
2398 /* By default, put trampoline templates in read-only data section. */
2399
2400 #ifdef TRAMPOLINE_SECTION
2401 switch_to_section (TRAMPOLINE_SECTION);
2402 #else
2403 switch_to_section (readonly_data_section);
2404 #endif
2405
2406 /* Write the assembler code to define one. */
2407 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2408 if (align > 0)
2409 ASM_OUTPUT_ALIGN (asm_out_file, align);
2410
2411 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2412 targetm.asm_out.trampoline_template (asm_out_file);
2413
2414 /* Record the rtl to refer to it. */
2415 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2416 name = ggc_strdup (label);
2417 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2418 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2419
2420 initial_trampoline = gen_const_mem (BLKmode, symbol);
2421 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2422 set_mem_size (initial_trampoline, TRAMPOLINE_SIZE);
2423
2424 return initial_trampoline;
2425 }
2426 \f
2427 /* A and B are either alignments or offsets. Return the minimum alignment
2428 that may be assumed after adding the two together. */
2429
2430 static inline unsigned
2431 min_align (unsigned int a, unsigned int b)
2432 {
2433 return (a | b) & -(a | b);
2434 }
2435
2436 /* Return the assembler directive for creating a given kind of integer
2437 object. SIZE is the number of bytes in the object and ALIGNED_P
2438 indicates whether it is known to be aligned. Return NULL if the
2439 assembly dialect has no such directive.
2440
2441 The returned string should be printed at the start of a new line and
2442 be followed immediately by the object's initial value. */
2443
2444 const char *
2445 integer_asm_op (int size, int aligned_p)
2446 {
2447 struct asm_int_op *ops;
2448
2449 if (aligned_p)
2450 ops = &targetm.asm_out.aligned_op;
2451 else
2452 ops = &targetm.asm_out.unaligned_op;
2453
2454 switch (size)
2455 {
2456 case 1:
2457 return targetm.asm_out.byte_op;
2458 case 2:
2459 return ops->hi;
2460 case 4:
2461 return ops->si;
2462 case 8:
2463 return ops->di;
2464 case 16:
2465 return ops->ti;
2466 default:
2467 return NULL;
2468 }
2469 }
2470
2471 /* Use directive OP to assemble an integer object X. Print OP at the
2472 start of the line, followed immediately by the value of X. */
2473
2474 void
2475 assemble_integer_with_op (const char *op, rtx x)
2476 {
2477 fputs (op, asm_out_file);
2478 output_addr_const (asm_out_file, x);
2479 fputc ('\n', asm_out_file);
2480 }
2481
2482 /* The default implementation of the asm_out.integer target hook. */
2483
2484 bool
2485 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2486 unsigned int size ATTRIBUTE_UNUSED,
2487 int aligned_p ATTRIBUTE_UNUSED)
2488 {
2489 const char *op = integer_asm_op (size, aligned_p);
2490 /* Avoid GAS bugs for large values. Specifically negative values whose
2491 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2492 if (size > UNITS_PER_WORD && size > POINTER_SIZE / BITS_PER_UNIT)
2493 return false;
2494 return op && (assemble_integer_with_op (op, x), true);
2495 }
2496
2497 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2498 the alignment of the integer in bits. Return 1 if we were able to output
2499 the constant, otherwise 0. We must be able to output the constant,
2500 if FORCE is nonzero. */
2501
2502 bool
2503 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2504 {
2505 int aligned_p;
2506
2507 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2508
2509 /* See if the target hook can handle this kind of object. */
2510 if (targetm.asm_out.integer (x, size, aligned_p))
2511 return true;
2512
2513 /* If the object is a multi-byte one, try splitting it up. Split
2514 it into words it if is multi-word, otherwise split it into bytes. */
2515 if (size > 1)
2516 {
2517 enum machine_mode omode, imode;
2518 unsigned int subalign;
2519 unsigned int subsize, i;
2520 enum mode_class mclass;
2521
2522 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2523 subalign = MIN (align, subsize * BITS_PER_UNIT);
2524 if (GET_CODE (x) == CONST_FIXED)
2525 mclass = GET_MODE_CLASS (GET_MODE (x));
2526 else
2527 mclass = MODE_INT;
2528
2529 omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0);
2530 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0);
2531
2532 for (i = 0; i < size; i += subsize)
2533 {
2534 rtx partial = simplify_subreg (omode, x, imode, i);
2535 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2536 break;
2537 }
2538 if (i == size)
2539 return true;
2540
2541 /* If we've printed some of it, but not all of it, there's no going
2542 back now. */
2543 gcc_assert (!i);
2544 }
2545
2546 gcc_assert (!force);
2547
2548 return false;
2549 }
2550 \f
2551 void
2552 assemble_real (REAL_VALUE_TYPE d, enum machine_mode mode, unsigned int align)
2553 {
2554 long data[4] = {0, 0, 0, 0};
2555 int i;
2556 int bitsize, nelts, nunits, units_per;
2557
2558 /* This is hairy. We have a quantity of known size. real_to_target
2559 will put it into an array of *host* longs, 32 bits per element
2560 (even if long is more than 32 bits). We need to determine the
2561 number of array elements that are occupied (nelts) and the number
2562 of *target* min-addressable units that will be occupied in the
2563 object file (nunits). We cannot assume that 32 divides the
2564 mode's bitsize (size * BITS_PER_UNIT) evenly.
2565
2566 size * BITS_PER_UNIT is used here to make sure that padding bits
2567 (which might appear at either end of the value; real_to_target
2568 will include the padding bits in its output array) are included. */
2569
2570 nunits = GET_MODE_SIZE (mode);
2571 bitsize = nunits * BITS_PER_UNIT;
2572 nelts = CEIL (bitsize, 32);
2573 units_per = 32 / BITS_PER_UNIT;
2574
2575 real_to_target (data, &d, mode);
2576
2577 /* Put out the first word with the specified alignment. */
2578 assemble_integer (GEN_INT (data[0]), MIN (nunits, units_per), align, 1);
2579 nunits -= units_per;
2580
2581 /* Subsequent words need only 32-bit alignment. */
2582 align = min_align (align, 32);
2583
2584 for (i = 1; i < nelts; i++)
2585 {
2586 assemble_integer (GEN_INT (data[i]), MIN (nunits, units_per), align, 1);
2587 nunits -= units_per;
2588 }
2589 }
2590 \f
2591 /* Given an expression EXP with a constant value,
2592 reduce it to the sum of an assembler symbol and an integer.
2593 Store them both in the structure *VALUE.
2594 EXP must be reducible. */
2595
2596 struct addr_const {
2597 rtx base;
2598 HOST_WIDE_INT offset;
2599 };
2600
2601 static void
2602 decode_addr_const (tree exp, struct addr_const *value)
2603 {
2604 tree target = TREE_OPERAND (exp, 0);
2605 int offset = 0;
2606 rtx x;
2607
2608 while (1)
2609 {
2610 if (TREE_CODE (target) == COMPONENT_REF
2611 && host_integerp (byte_position (TREE_OPERAND (target, 1)), 0))
2612 {
2613 offset += int_byte_position (TREE_OPERAND (target, 1));
2614 target = TREE_OPERAND (target, 0);
2615 }
2616 else if (TREE_CODE (target) == ARRAY_REF
2617 || TREE_CODE (target) == ARRAY_RANGE_REF)
2618 {
2619 offset += (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (target)), 1)
2620 * tree_low_cst (TREE_OPERAND (target, 1), 0));
2621 target = TREE_OPERAND (target, 0);
2622 }
2623 else if (TREE_CODE (target) == MEM_REF
2624 && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR)
2625 {
2626 offset += mem_ref_offset (target).low;
2627 target = TREE_OPERAND (TREE_OPERAND (target, 0), 0);
2628 }
2629 else if (TREE_CODE (target) == INDIRECT_REF
2630 && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR
2631 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0))
2632 == ADDR_EXPR)
2633 target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0);
2634 else
2635 break;
2636 }
2637
2638 switch (TREE_CODE (target))
2639 {
2640 case VAR_DECL:
2641 case FUNCTION_DECL:
2642 x = DECL_RTL (target);
2643 break;
2644
2645 case LABEL_DECL:
2646 x = gen_rtx_MEM (FUNCTION_MODE,
2647 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2648 break;
2649
2650 case REAL_CST:
2651 case FIXED_CST:
2652 case STRING_CST:
2653 case COMPLEX_CST:
2654 case CONSTRUCTOR:
2655 case INTEGER_CST:
2656 x = output_constant_def (target, 1);
2657 break;
2658
2659 default:
2660 gcc_unreachable ();
2661 }
2662
2663 gcc_assert (MEM_P (x));
2664 x = XEXP (x, 0);
2665
2666 value->base = x;
2667 value->offset = offset;
2668 }
2669 \f
2670
2671 static GTY((param_is (struct constant_descriptor_tree)))
2672 htab_t const_desc_htab;
2673
2674 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2675
2676 /* Constant pool accessor function. */
2677
2678 htab_t
2679 constant_pool_htab (void)
2680 {
2681 return const_desc_htab;
2682 }
2683
2684 /* Compute a hash code for a constant expression. */
2685
2686 static hashval_t
2687 const_desc_hash (const void *ptr)
2688 {
2689 return ((const struct constant_descriptor_tree *)ptr)->hash;
2690 }
2691
2692 static hashval_t
2693 const_hash_1 (const tree exp)
2694 {
2695 const char *p;
2696 hashval_t hi;
2697 int len, i;
2698 enum tree_code code = TREE_CODE (exp);
2699
2700 /* Either set P and LEN to the address and len of something to hash and
2701 exit the switch or return a value. */
2702
2703 switch (code)
2704 {
2705 case INTEGER_CST:
2706 p = (char *) &TREE_INT_CST (exp);
2707 len = sizeof TREE_INT_CST (exp);
2708 break;
2709
2710 case REAL_CST:
2711 return real_hash (TREE_REAL_CST_PTR (exp));
2712
2713 case FIXED_CST:
2714 return fixed_hash (TREE_FIXED_CST_PTR (exp));
2715
2716 case STRING_CST:
2717 p = TREE_STRING_POINTER (exp);
2718 len = TREE_STRING_LENGTH (exp);
2719 break;
2720
2721 case COMPLEX_CST:
2722 return (const_hash_1 (TREE_REALPART (exp)) * 5
2723 + const_hash_1 (TREE_IMAGPART (exp)));
2724
2725 case VECTOR_CST:
2726 {
2727 unsigned i;
2728
2729 hi = 7 + VECTOR_CST_NELTS (exp);
2730
2731 for (i = 0; i < VECTOR_CST_NELTS (exp); ++i)
2732 hi = hi * 563 + const_hash_1 (VECTOR_CST_ELT (exp, i));
2733
2734 return hi;
2735 }
2736
2737 case CONSTRUCTOR:
2738 {
2739 unsigned HOST_WIDE_INT idx;
2740 tree value;
2741
2742 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2743
2744 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
2745 if (value)
2746 hi = hi * 603 + const_hash_1 (value);
2747
2748 return hi;
2749 }
2750
2751 case ADDR_EXPR:
2752 case FDESC_EXPR:
2753 {
2754 struct addr_const value;
2755
2756 decode_addr_const (exp, &value);
2757 switch (GET_CODE (value.base))
2758 {
2759 case SYMBOL_REF:
2760 /* Don't hash the address of the SYMBOL_REF;
2761 only use the offset and the symbol name. */
2762 hi = value.offset;
2763 p = XSTR (value.base, 0);
2764 for (i = 0; p[i] != 0; i++)
2765 hi = ((hi * 613) + (unsigned) (p[i]));
2766 break;
2767
2768 case LABEL_REF:
2769 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13;
2770 break;
2771
2772 default:
2773 gcc_unreachable ();
2774 }
2775 }
2776 return hi;
2777
2778 case PLUS_EXPR:
2779 case POINTER_PLUS_EXPR:
2780 case MINUS_EXPR:
2781 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2782 + const_hash_1 (TREE_OPERAND (exp, 1)));
2783
2784 CASE_CONVERT:
2785 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
2786
2787 default:
2788 /* A language specific constant. Just hash the code. */
2789 return code;
2790 }
2791
2792 /* Compute hashing function. */
2793 hi = len;
2794 for (i = 0; i < len; i++)
2795 hi = ((hi * 613) + (unsigned) (p[i]));
2796
2797 return hi;
2798 }
2799
2800 /* Wrapper of compare_constant, for the htab interface. */
2801 static int
2802 const_desc_eq (const void *p1, const void *p2)
2803 {
2804 const struct constant_descriptor_tree *const c1
2805 = (const struct constant_descriptor_tree *) p1;
2806 const struct constant_descriptor_tree *const c2
2807 = (const struct constant_descriptor_tree *) p2;
2808 if (c1->hash != c2->hash)
2809 return 0;
2810 return compare_constant (c1->value, c2->value);
2811 }
2812
2813 /* Compare t1 and t2, and return 1 only if they are known to result in
2814 the same bit pattern on output. */
2815
2816 static int
2817 compare_constant (const tree t1, const tree t2)
2818 {
2819 enum tree_code typecode;
2820
2821 if (t1 == NULL_TREE)
2822 return t2 == NULL_TREE;
2823 if (t2 == NULL_TREE)
2824 return 0;
2825
2826 if (TREE_CODE (t1) != TREE_CODE (t2))
2827 return 0;
2828
2829 switch (TREE_CODE (t1))
2830 {
2831 case INTEGER_CST:
2832 /* Integer constants are the same only if the same width of type. */
2833 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2834 return 0;
2835 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2836 return 0;
2837 return tree_int_cst_equal (t1, t2);
2838
2839 case REAL_CST:
2840 /* Real constants are the same only if the same width of type. */
2841 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2842 return 0;
2843
2844 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
2845
2846 case FIXED_CST:
2847 /* Fixed constants are the same only if the same width of type. */
2848 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2849 return 0;
2850
2851 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
2852
2853 case STRING_CST:
2854 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2855 return 0;
2856
2857 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
2858 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
2859 TREE_STRING_LENGTH (t1)));
2860
2861 case COMPLEX_CST:
2862 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
2863 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
2864
2865 case VECTOR_CST:
2866 {
2867 unsigned i;
2868
2869 if (VECTOR_CST_NELTS (t1) != VECTOR_CST_NELTS (t2))
2870 return 0;
2871
2872 for (i = 0; i < VECTOR_CST_NELTS (t1); ++i)
2873 if (!compare_constant (VECTOR_CST_ELT (t1, i),
2874 VECTOR_CST_ELT (t2, i)))
2875 return 0;
2876
2877 return 1;
2878 }
2879
2880 case CONSTRUCTOR:
2881 {
2882 vec<constructor_elt, va_gc> *v1, *v2;
2883 unsigned HOST_WIDE_INT idx;
2884
2885 typecode = TREE_CODE (TREE_TYPE (t1));
2886 if (typecode != TREE_CODE (TREE_TYPE (t2)))
2887 return 0;
2888
2889 if (typecode == ARRAY_TYPE)
2890 {
2891 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
2892 /* For arrays, check that the sizes all match. */
2893 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
2894 || size_1 == -1
2895 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
2896 return 0;
2897 }
2898 else
2899 {
2900 /* For record and union constructors, require exact type
2901 equality. */
2902 if (TREE_TYPE (t1) != TREE_TYPE (t2))
2903 return 0;
2904 }
2905
2906 v1 = CONSTRUCTOR_ELTS (t1);
2907 v2 = CONSTRUCTOR_ELTS (t2);
2908 if (vec_safe_length (v1) != vec_safe_length (v2))
2909 return 0;
2910
2911 for (idx = 0; idx < vec_safe_length (v1); ++idx)
2912 {
2913 constructor_elt *c1 = &(*v1)[idx];
2914 constructor_elt *c2 = &(*v2)[idx];
2915
2916 /* Check that each value is the same... */
2917 if (!compare_constant (c1->value, c2->value))
2918 return 0;
2919 /* ... and that they apply to the same fields! */
2920 if (typecode == ARRAY_TYPE)
2921 {
2922 if (!compare_constant (c1->index, c2->index))
2923 return 0;
2924 }
2925 else
2926 {
2927 if (c1->index != c2->index)
2928 return 0;
2929 }
2930 }
2931
2932 return 1;
2933 }
2934
2935 case ADDR_EXPR:
2936 case FDESC_EXPR:
2937 {
2938 struct addr_const value1, value2;
2939 enum rtx_code code;
2940 int ret;
2941
2942 decode_addr_const (t1, &value1);
2943 decode_addr_const (t2, &value2);
2944
2945 if (value1.offset != value2.offset)
2946 return 0;
2947
2948 code = GET_CODE (value1.base);
2949 if (code != GET_CODE (value2.base))
2950 return 0;
2951
2952 switch (code)
2953 {
2954 case SYMBOL_REF:
2955 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
2956 break;
2957
2958 case LABEL_REF:
2959 ret = (CODE_LABEL_NUMBER (XEXP (value1.base, 0))
2960 == CODE_LABEL_NUMBER (XEXP (value2.base, 0)));
2961 break;
2962
2963 default:
2964 gcc_unreachable ();
2965 }
2966 return ret;
2967 }
2968
2969 case PLUS_EXPR:
2970 case POINTER_PLUS_EXPR:
2971 case MINUS_EXPR:
2972 case RANGE_EXPR:
2973 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
2974 && compare_constant(TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
2975
2976 CASE_CONVERT:
2977 case VIEW_CONVERT_EXPR:
2978 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
2979
2980 default:
2981 return 0;
2982 }
2983
2984 gcc_unreachable ();
2985 }
2986 \f
2987 /* Make a copy of the whole tree structure for a constant. This
2988 handles the same types of nodes that compare_constant handles. */
2989
2990 static tree
2991 copy_constant (tree exp)
2992 {
2993 switch (TREE_CODE (exp))
2994 {
2995 case ADDR_EXPR:
2996 /* For ADDR_EXPR, we do not want to copy the decl whose address
2997 is requested. We do want to copy constants though. */
2998 if (CONSTANT_CLASS_P (TREE_OPERAND (exp, 0)))
2999 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
3000 copy_constant (TREE_OPERAND (exp, 0)));
3001 else
3002 return copy_node (exp);
3003
3004 case INTEGER_CST:
3005 case REAL_CST:
3006 case FIXED_CST:
3007 case STRING_CST:
3008 return copy_node (exp);
3009
3010 case COMPLEX_CST:
3011 return build_complex (TREE_TYPE (exp),
3012 copy_constant (TREE_REALPART (exp)),
3013 copy_constant (TREE_IMAGPART (exp)));
3014
3015 case PLUS_EXPR:
3016 case POINTER_PLUS_EXPR:
3017 case MINUS_EXPR:
3018 return build2 (TREE_CODE (exp), TREE_TYPE (exp),
3019 copy_constant (TREE_OPERAND (exp, 0)),
3020 copy_constant (TREE_OPERAND (exp, 1)));
3021
3022 CASE_CONVERT:
3023 case VIEW_CONVERT_EXPR:
3024 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
3025 copy_constant (TREE_OPERAND (exp, 0)));
3026
3027 case VECTOR_CST:
3028 return build_vector (TREE_TYPE (exp), VECTOR_CST_ELTS (exp));
3029
3030 case CONSTRUCTOR:
3031 {
3032 tree copy = copy_node (exp);
3033 vec<constructor_elt, va_gc> *v;
3034 unsigned HOST_WIDE_INT idx;
3035 tree purpose, value;
3036
3037 vec_alloc (v, vec_safe_length (CONSTRUCTOR_ELTS (exp)));
3038 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (exp), idx, purpose, value)
3039 {
3040 constructor_elt ce = {purpose, copy_constant (value)};
3041 v->quick_push (ce);
3042 }
3043 CONSTRUCTOR_ELTS (copy) = v;
3044 return copy;
3045 }
3046
3047 default:
3048 gcc_unreachable ();
3049 }
3050 }
3051 \f
3052 /* Return the section into which constant EXP should be placed. */
3053
3054 static section *
3055 get_constant_section (tree exp, unsigned int align)
3056 {
3057 return targetm.asm_out.select_section (exp,
3058 compute_reloc_for_constant (exp),
3059 align);
3060 }
3061
3062 /* Return the size of constant EXP in bytes. */
3063
3064 static HOST_WIDE_INT
3065 get_constant_size (tree exp)
3066 {
3067 HOST_WIDE_INT size;
3068
3069 size = int_size_in_bytes (TREE_TYPE (exp));
3070 if (TREE_CODE (exp) == STRING_CST)
3071 size = MAX (TREE_STRING_LENGTH (exp), size);
3072 return size;
3073 }
3074
3075 /* Subroutine of output_constant_def:
3076 No constant equal to EXP is known to have been output.
3077 Make a constant descriptor to enter EXP in the hash table.
3078 Assign the label number and construct RTL to refer to the
3079 constant's location in memory.
3080 Caller is responsible for updating the hash table. */
3081
3082 static struct constant_descriptor_tree *
3083 build_constant_desc (tree exp)
3084 {
3085 struct constant_descriptor_tree *desc;
3086 rtx symbol, rtl;
3087 char label[256];
3088 int labelno;
3089 tree decl;
3090
3091 desc = ggc_alloc_constant_descriptor_tree ();
3092 desc->value = copy_constant (exp);
3093
3094 /* Propagate marked-ness to copied constant. */
3095 if (flag_mudflap && mf_marked_p (exp))
3096 mf_mark (desc->value);
3097
3098 /* Create a string containing the label name, in LABEL. */
3099 labelno = const_labelno++;
3100 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3101
3102 /* Construct the VAR_DECL associated with the constant. */
3103 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3104 TREE_TYPE (exp));
3105 DECL_ARTIFICIAL (decl) = 1;
3106 DECL_IGNORED_P (decl) = 1;
3107 TREE_READONLY (decl) = 1;
3108 TREE_STATIC (decl) = 1;
3109 TREE_ADDRESSABLE (decl) = 1;
3110 /* We don't set the RTL yet as this would cause varpool to assume that the
3111 variable is referenced. Moreover, it would just be dropped in LTO mode.
3112 Instead we set the flag that will be recognized in make_decl_rtl. */
3113 DECL_IN_CONSTANT_POOL (decl) = 1;
3114 DECL_INITIAL (decl) = desc->value;
3115 /* ??? CONSTANT_ALIGNMENT hasn't been updated for vector types on most
3116 architectures so use DATA_ALIGNMENT as well, except for strings. */
3117 if (TREE_CODE (exp) == STRING_CST)
3118 {
3119 #ifdef CONSTANT_ALIGNMENT
3120 DECL_ALIGN (decl) = CONSTANT_ALIGNMENT (exp, DECL_ALIGN (decl));
3121 #endif
3122 }
3123 else
3124 align_variable (decl, 0);
3125
3126 /* Now construct the SYMBOL_REF and the MEM. */
3127 if (use_object_blocks_p ())
3128 {
3129 section *sect = get_constant_section (exp, DECL_ALIGN (decl));
3130 symbol = create_block_symbol (ggc_strdup (label),
3131 get_block_for_section (sect), -1);
3132 }
3133 else
3134 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3135 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3136 SET_SYMBOL_REF_DECL (symbol, decl);
3137 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3138
3139 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3140 set_mem_attributes (rtl, exp, 1);
3141 set_mem_alias_set (rtl, 0);
3142 set_mem_alias_set (rtl, const_alias_set);
3143
3144 /* We cannot share RTX'es in pool entries.
3145 Mark this piece of RTL as required for unsharing. */
3146 RTX_FLAG (rtl, used) = 1;
3147
3148 /* Set flags or add text to the name to record information, such as
3149 that it is a local symbol. If the name is changed, the macro
3150 ASM_OUTPUT_LABELREF will have to know how to strip this
3151 information. This call might invalidate our local variable
3152 SYMBOL; we can't use it afterward. */
3153 targetm.encode_section_info (exp, rtl, true);
3154
3155 desc->rtl = rtl;
3156
3157 return desc;
3158 }
3159
3160 /* Return an rtx representing a reference to constant data in memory
3161 for the constant expression EXP.
3162
3163 If assembler code for such a constant has already been output,
3164 return an rtx to refer to it.
3165 Otherwise, output such a constant in memory
3166 and generate an rtx for it.
3167
3168 If DEFER is nonzero, this constant can be deferred and output only
3169 if referenced in the function after all optimizations.
3170
3171 `const_desc_table' records which constants already have label strings. */
3172
3173 rtx
3174 output_constant_def (tree exp, int defer)
3175 {
3176 struct constant_descriptor_tree *desc;
3177 struct constant_descriptor_tree key;
3178 void **loc;
3179
3180 /* Look up EXP in the table of constant descriptors. If we didn't find
3181 it, create a new one. */
3182 key.value = exp;
3183 key.hash = const_hash_1 (exp);
3184 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3185
3186 desc = (struct constant_descriptor_tree *) *loc;
3187 if (desc == 0)
3188 {
3189 desc = build_constant_desc (exp);
3190 desc->hash = key.hash;
3191 *loc = desc;
3192 }
3193
3194 maybe_output_constant_def_contents (desc, defer);
3195 return desc->rtl;
3196 }
3197
3198 /* Subroutine of output_constant_def: Decide whether or not we need to
3199 output the constant DESC now, and if so, do it. */
3200 static void
3201 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3202 int defer)
3203 {
3204 rtx symbol = XEXP (desc->rtl, 0);
3205 tree exp = desc->value;
3206
3207 if (flag_syntax_only)
3208 return;
3209
3210 if (TREE_ASM_WRITTEN (exp))
3211 /* Already output; don't do it again. */
3212 return;
3213
3214 /* We can always defer constants as long as the context allows
3215 doing so. */
3216 if (defer)
3217 {
3218 /* Increment n_deferred_constants if it exists. It needs to be at
3219 least as large as the number of constants actually referred to
3220 by the function. If it's too small we'll stop looking too early
3221 and fail to emit constants; if it's too large we'll only look
3222 through the entire function when we could have stopped earlier. */
3223 if (cfun)
3224 n_deferred_constants++;
3225 return;
3226 }
3227
3228 output_constant_def_contents (symbol);
3229 }
3230
3231 /* Subroutine of output_constant_def_contents. Output the definition
3232 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3233 constant's alignment in bits. */
3234
3235 static void
3236 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3237 {
3238 HOST_WIDE_INT size;
3239
3240 size = get_constant_size (exp);
3241
3242 /* Do any machine/system dependent processing of the constant. */
3243 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3244
3245 /* Output the value of EXP. */
3246 output_constant (exp, size, align);
3247 }
3248
3249 /* We must output the constant data referred to by SYMBOL; do so. */
3250
3251 static void
3252 output_constant_def_contents (rtx symbol)
3253 {
3254 tree decl = SYMBOL_REF_DECL (symbol);
3255 tree exp = DECL_INITIAL (decl);
3256 unsigned int align;
3257 bool asan_protected = false;
3258
3259 /* Make sure any other constants whose addresses appear in EXP
3260 are assigned label numbers. */
3261 output_addressed_constants (exp);
3262
3263 /* We are no longer deferring this constant. */
3264 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3265
3266 if (flag_asan && TREE_CODE (exp) == STRING_CST
3267 && asan_protect_global (exp))
3268 {
3269 asan_protected = true;
3270 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
3271 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
3272 }
3273
3274 /* If the constant is part of an object block, make sure that the
3275 decl has been positioned within its block, but do not write out
3276 its definition yet. output_object_blocks will do that later. */
3277 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3278 place_block_symbol (symbol);
3279 else
3280 {
3281 align = DECL_ALIGN (decl);
3282 switch_to_section (get_constant_section (exp, align));
3283 if (align > BITS_PER_UNIT)
3284 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3285 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3286 if (asan_protected)
3287 {
3288 HOST_WIDE_INT size = get_constant_size (exp);
3289 assemble_zeros (asan_red_zone_size (size));
3290 }
3291 }
3292 if (flag_mudflap)
3293 mudflap_enqueue_constant (exp);
3294 }
3295
3296 /* Look up EXP in the table of constant descriptors. Return the rtl
3297 if it has been emitted, else null. */
3298
3299 rtx
3300 lookup_constant_def (tree exp)
3301 {
3302 struct constant_descriptor_tree *desc;
3303 struct constant_descriptor_tree key;
3304
3305 key.value = exp;
3306 key.hash = const_hash_1 (exp);
3307 desc = (struct constant_descriptor_tree *)
3308 htab_find_with_hash (const_desc_htab, &key, key.hash);
3309
3310 return (desc ? desc->rtl : NULL_RTX);
3311 }
3312
3313 /* Return a tree representing a reference to constant data in memory
3314 for the constant expression EXP.
3315
3316 This is the counterpart of output_constant_def at the Tree level. */
3317
3318 tree
3319 tree_output_constant_def (tree exp)
3320 {
3321 struct constant_descriptor_tree *desc, key;
3322 void **loc;
3323 tree decl;
3324
3325 /* Look up EXP in the table of constant descriptors. If we didn't find
3326 it, create a new one. */
3327 key.value = exp;
3328 key.hash = const_hash_1 (exp);
3329 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3330
3331 desc = (struct constant_descriptor_tree *) *loc;
3332 if (desc == 0)
3333 {
3334 desc = build_constant_desc (exp);
3335 desc->hash = key.hash;
3336 *loc = desc;
3337 }
3338
3339 decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3340 varpool_finalize_decl (decl);
3341 return decl;
3342 }
3343 \f
3344 /* Used in the hash tables to avoid outputting the same constant
3345 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3346 are output once per function, not once per file. */
3347 /* ??? Only a few targets need per-function constant pools. Most
3348 can use one per-file pool. Should add a targetm bit to tell the
3349 difference. */
3350
3351 struct GTY(()) rtx_constant_pool {
3352 /* Pointers to first and last constant in pool, as ordered by offset. */
3353 struct constant_descriptor_rtx *first;
3354 struct constant_descriptor_rtx *last;
3355
3356 /* Hash facility for making memory-constants from constant rtl-expressions.
3357 It is used on RISC machines where immediate integer arguments and
3358 constant addresses are restricted so that such constants must be stored
3359 in memory. */
3360 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_htab;
3361
3362 /* Current offset in constant pool (does not include any
3363 machine-specific header). */
3364 HOST_WIDE_INT offset;
3365 };
3366
3367 struct GTY((chain_next ("%h.next"))) constant_descriptor_rtx {
3368 struct constant_descriptor_rtx *next;
3369 rtx mem;
3370 rtx sym;
3371 rtx constant;
3372 HOST_WIDE_INT offset;
3373 hashval_t hash;
3374 enum machine_mode mode;
3375 unsigned int align;
3376 int labelno;
3377 int mark;
3378 };
3379
3380 /* Hash and compare functions for const_rtx_htab. */
3381
3382 static hashval_t
3383 const_desc_rtx_hash (const void *ptr)
3384 {
3385 const struct constant_descriptor_rtx *const desc
3386 = (const struct constant_descriptor_rtx *) ptr;
3387 return desc->hash;
3388 }
3389
3390 static int
3391 const_desc_rtx_eq (const void *a, const void *b)
3392 {
3393 const struct constant_descriptor_rtx *const x
3394 = (const struct constant_descriptor_rtx *) a;
3395 const struct constant_descriptor_rtx *const y
3396 = (const struct constant_descriptor_rtx *) b;
3397
3398 if (x->mode != y->mode)
3399 return 0;
3400 return rtx_equal_p (x->constant, y->constant);
3401 }
3402
3403 /* This is the worker function for const_rtx_hash, called via for_each_rtx. */
3404
3405 static int
3406 const_rtx_hash_1 (rtx *xp, void *data)
3407 {
3408 unsigned HOST_WIDE_INT hwi;
3409 enum machine_mode mode;
3410 enum rtx_code code;
3411 hashval_t h, *hp;
3412 rtx x;
3413
3414 x = *xp;
3415 code = GET_CODE (x);
3416 mode = GET_MODE (x);
3417 h = (hashval_t) code * 1048573 + mode;
3418
3419 switch (code)
3420 {
3421 case CONST_INT:
3422 hwi = INTVAL (x);
3423 fold_hwi:
3424 {
3425 int shift = sizeof (hashval_t) * CHAR_BIT;
3426 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3427 int i;
3428
3429 h ^= (hashval_t) hwi;
3430 for (i = 1; i < n; ++i)
3431 {
3432 hwi >>= shift;
3433 h ^= (hashval_t) hwi;
3434 }
3435 }
3436 break;
3437
3438 case CONST_DOUBLE:
3439 if (mode == VOIDmode)
3440 {
3441 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3442 goto fold_hwi;
3443 }
3444 else
3445 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3446 break;
3447
3448 case CONST_FIXED:
3449 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3450 break;
3451
3452 case CONST_VECTOR:
3453 {
3454 int i;
3455 for (i = XVECLEN (x, 0); i-- > 0; )
3456 h = h * 251 + const_rtx_hash_1 (&XVECEXP (x, 0, i), data);
3457 }
3458 break;
3459
3460 case SYMBOL_REF:
3461 h ^= htab_hash_string (XSTR (x, 0));
3462 break;
3463
3464 case LABEL_REF:
3465 h = h * 251 + CODE_LABEL_NUMBER (XEXP (x, 0));
3466 break;
3467
3468 case UNSPEC:
3469 case UNSPEC_VOLATILE:
3470 h = h * 251 + XINT (x, 1);
3471 break;
3472
3473 default:
3474 break;
3475 }
3476
3477 hp = (hashval_t *) data;
3478 *hp = *hp * 509 + h;
3479 return 0;
3480 }
3481
3482 /* Compute a hash value for X, which should be a constant. */
3483
3484 static hashval_t
3485 const_rtx_hash (rtx x)
3486 {
3487 hashval_t h = 0;
3488 for_each_rtx (&x, const_rtx_hash_1, &h);
3489 return h;
3490 }
3491
3492 \f
3493 /* Create and return a new rtx constant pool. */
3494
3495 static struct rtx_constant_pool *
3496 create_constant_pool (void)
3497 {
3498 struct rtx_constant_pool *pool;
3499
3500 pool = ggc_alloc_rtx_constant_pool ();
3501 pool->const_rtx_htab = htab_create_ggc (31, const_desc_rtx_hash,
3502 const_desc_rtx_eq, NULL);
3503 pool->first = NULL;
3504 pool->last = NULL;
3505 pool->offset = 0;
3506 return pool;
3507 }
3508
3509 /* Initialize constant pool hashing for a new function. */
3510
3511 void
3512 init_varasm_status (void)
3513 {
3514 crtl->varasm.pool = create_constant_pool ();
3515 crtl->varasm.deferred_constants = 0;
3516 }
3517 \f
3518 /* Given a MINUS expression, simplify it if both sides
3519 include the same symbol. */
3520
3521 rtx
3522 simplify_subtraction (rtx x)
3523 {
3524 rtx r = simplify_rtx (x);
3525 return r ? r : x;
3526 }
3527 \f
3528 /* Given a constant rtx X, make (or find) a memory constant for its value
3529 and return a MEM rtx to refer to it in memory. */
3530
3531 rtx
3532 force_const_mem (enum machine_mode mode, rtx x)
3533 {
3534 struct constant_descriptor_rtx *desc, tmp;
3535 struct rtx_constant_pool *pool;
3536 char label[256];
3537 rtx def, symbol;
3538 hashval_t hash;
3539 unsigned int align;
3540 void **slot;
3541
3542 /* If we're not allowed to drop X into the constant pool, don't. */
3543 if (targetm.cannot_force_const_mem (mode, x))
3544 return NULL_RTX;
3545
3546 /* Record that this function has used a constant pool entry. */
3547 crtl->uses_const_pool = 1;
3548
3549 /* Decide which pool to use. */
3550 pool = (targetm.use_blocks_for_constant_p (mode, x)
3551 ? shared_constant_pool
3552 : crtl->varasm.pool);
3553
3554 /* Lookup the value in the hashtable. */
3555 tmp.constant = x;
3556 tmp.mode = mode;
3557 hash = const_rtx_hash (x);
3558 slot = htab_find_slot_with_hash (pool->const_rtx_htab, &tmp, hash, INSERT);
3559 desc = (struct constant_descriptor_rtx *) *slot;
3560
3561 /* If the constant was already present, return its memory. */
3562 if (desc)
3563 return copy_rtx (desc->mem);
3564
3565 /* Otherwise, create a new descriptor. */
3566 desc = ggc_alloc_constant_descriptor_rtx ();
3567 *slot = desc;
3568
3569 /* Align the location counter as required by EXP's data type. */
3570 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3571 #ifdef CONSTANT_ALIGNMENT
3572 {
3573 tree type = lang_hooks.types.type_for_mode (mode, 0);
3574 if (type != NULL_TREE)
3575 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3576 }
3577 #endif
3578
3579 pool->offset += (align / BITS_PER_UNIT) - 1;
3580 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3581
3582 desc->next = NULL;
3583 desc->constant = copy_rtx (tmp.constant);
3584 desc->offset = pool->offset;
3585 desc->hash = hash;
3586 desc->mode = mode;
3587 desc->align = align;
3588 desc->labelno = const_labelno;
3589 desc->mark = 0;
3590
3591 pool->offset += GET_MODE_SIZE (mode);
3592 if (pool->last)
3593 pool->last->next = desc;
3594 else
3595 pool->first = pool->last = desc;
3596 pool->last = desc;
3597
3598 /* Create a string containing the label name, in LABEL. */
3599 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3600 ++const_labelno;
3601
3602 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3603 the constants pool. */
3604 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3605 {
3606 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3607 symbol = create_block_symbol (ggc_strdup (label),
3608 get_block_for_section (sect), -1);
3609 }
3610 else
3611 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3612 desc->sym = symbol;
3613 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3614 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3615 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3616
3617 /* Construct the MEM. */
3618 desc->mem = def = gen_const_mem (mode, symbol);
3619 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3620 set_mem_align (def, align);
3621
3622 /* If we're dropping a label to the constant pool, make sure we
3623 don't delete it. */
3624 if (GET_CODE (x) == LABEL_REF)
3625 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3626
3627 return copy_rtx (def);
3628 }
3629 \f
3630 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3631
3632 rtx
3633 get_pool_constant (rtx addr)
3634 {
3635 return SYMBOL_REF_CONSTANT (addr)->constant;
3636 }
3637
3638 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3639 and whether it has been output or not. */
3640
3641 rtx
3642 get_pool_constant_mark (rtx addr, bool *pmarked)
3643 {
3644 struct constant_descriptor_rtx *desc;
3645
3646 desc = SYMBOL_REF_CONSTANT (addr);
3647 *pmarked = (desc->mark != 0);
3648 return desc->constant;
3649 }
3650
3651 /* Similar, return the mode. */
3652
3653 enum machine_mode
3654 get_pool_mode (const_rtx addr)
3655 {
3656 return SYMBOL_REF_CONSTANT (addr)->mode;
3657 }
3658
3659 /* Return the size of the constant pool. */
3660
3661 int
3662 get_pool_size (void)
3663 {
3664 return crtl->varasm.pool->offset;
3665 }
3666 \f
3667 /* Worker function for output_constant_pool_1. Emit assembly for X
3668 in MODE with known alignment ALIGN. */
3669
3670 static void
3671 output_constant_pool_2 (enum machine_mode mode, rtx x, unsigned int align)
3672 {
3673 switch (GET_MODE_CLASS (mode))
3674 {
3675 case MODE_FLOAT:
3676 case MODE_DECIMAL_FLOAT:
3677 {
3678 REAL_VALUE_TYPE r;
3679
3680 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3681 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3682 assemble_real (r, mode, align);
3683 break;
3684 }
3685
3686 case MODE_INT:
3687 case MODE_PARTIAL_INT:
3688 case MODE_FRACT:
3689 case MODE_UFRACT:
3690 case MODE_ACCUM:
3691 case MODE_UACCUM:
3692 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3693 break;
3694
3695 case MODE_VECTOR_FLOAT:
3696 case MODE_VECTOR_INT:
3697 case MODE_VECTOR_FRACT:
3698 case MODE_VECTOR_UFRACT:
3699 case MODE_VECTOR_ACCUM:
3700 case MODE_VECTOR_UACCUM:
3701 {
3702 int i, units;
3703 enum machine_mode submode = GET_MODE_INNER (mode);
3704 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3705
3706 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3707 units = CONST_VECTOR_NUNITS (x);
3708
3709 for (i = 0; i < units; i++)
3710 {
3711 rtx elt = CONST_VECTOR_ELT (x, i);
3712 output_constant_pool_2 (submode, elt, i ? subalign : align);
3713 }
3714 }
3715 break;
3716
3717 default:
3718 gcc_unreachable ();
3719 }
3720 }
3721
3722 /* Worker function for output_constant_pool. Emit constant DESC,
3723 giving it ALIGN bits of alignment. */
3724
3725 static void
3726 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3727 unsigned int align)
3728 {
3729 rtx x, tmp;
3730
3731 x = desc->constant;
3732
3733 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3734 whose CODE_LABEL has been deleted. This can occur if a jump table
3735 is eliminated by optimization. If so, write a constant of zero
3736 instead. Note that this can also happen by turning the
3737 CODE_LABEL into a NOTE. */
3738 /* ??? This seems completely and utterly wrong. Certainly it's
3739 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3740 functioning even with INSN_DELETED_P and friends. */
3741
3742 tmp = x;
3743 switch (GET_CODE (tmp))
3744 {
3745 case CONST:
3746 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3747 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
3748 break;
3749 tmp = XEXP (XEXP (tmp, 0), 0);
3750 /* FALLTHRU */
3751
3752 case LABEL_REF:
3753 tmp = XEXP (tmp, 0);
3754 gcc_assert (!INSN_DELETED_P (tmp));
3755 gcc_assert (!NOTE_P (tmp)
3756 || NOTE_KIND (tmp) != NOTE_INSN_DELETED);
3757 break;
3758
3759 default:
3760 break;
3761 }
3762
3763 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3764 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3765 align, desc->labelno, done);
3766 #endif
3767
3768 assemble_align (align);
3769
3770 /* Output the label. */
3771 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3772
3773 /* Output the data. */
3774 output_constant_pool_2 (desc->mode, x, align);
3775
3776 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3777 sections have proper size. */
3778 if (align > GET_MODE_BITSIZE (desc->mode)
3779 && in_section
3780 && (in_section->common.flags & SECTION_MERGE))
3781 assemble_align (align);
3782
3783 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3784 done:
3785 #endif
3786 return;
3787 }
3788
3789 /* Given a SYMBOL_REF CURRENT_RTX, mark it and all constants it refers
3790 to as used. Emit referenced deferred strings. This function can
3791 be used with for_each_rtx to mark all SYMBOL_REFs in an rtx. */
3792
3793 static int
3794 mark_constant (rtx *current_rtx, void *data ATTRIBUTE_UNUSED)
3795 {
3796 rtx x = *current_rtx;
3797
3798 if (x == NULL_RTX || GET_CODE (x) != SYMBOL_REF)
3799 return 0;
3800
3801 if (CONSTANT_POOL_ADDRESS_P (x))
3802 {
3803 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
3804 if (desc->mark == 0)
3805 {
3806 desc->mark = 1;
3807 for_each_rtx (&desc->constant, mark_constant, NULL);
3808 }
3809 }
3810 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3811 {
3812 tree decl = SYMBOL_REF_DECL (x);
3813 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
3814 {
3815 n_deferred_constants--;
3816 output_constant_def_contents (x);
3817 }
3818 }
3819
3820 return -1;
3821 }
3822
3823 /* Look through appropriate parts of INSN, marking all entries in the
3824 constant pool which are actually being used. Entries that are only
3825 referenced by other constants are also marked as used. Emit
3826 deferred strings that are used. */
3827
3828 static void
3829 mark_constants (rtx insn)
3830 {
3831 if (!INSN_P (insn))
3832 return;
3833
3834 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3835 insns, not any notes that may be attached. We don't want to mark
3836 a constant just because it happens to appear in a REG_EQUIV note. */
3837 if (GET_CODE (PATTERN (insn)) == SEQUENCE)
3838 {
3839 rtx seq = PATTERN (insn);
3840 int i, n = XVECLEN (seq, 0);
3841 for (i = 0; i < n; ++i)
3842 {
3843 rtx subinsn = XVECEXP (seq, 0, i);
3844 if (INSN_P (subinsn))
3845 for_each_rtx (&PATTERN (subinsn), mark_constant, NULL);
3846 }
3847 }
3848 else
3849 for_each_rtx (&PATTERN (insn), mark_constant, NULL);
3850 }
3851
3852 /* Look through the instructions for this function, and mark all the
3853 entries in POOL which are actually being used. Emit deferred constants
3854 which have indeed been used. */
3855
3856 static void
3857 mark_constant_pool (void)
3858 {
3859 rtx insn;
3860
3861 if (!crtl->uses_const_pool && n_deferred_constants == 0)
3862 return;
3863
3864 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3865 mark_constants (insn);
3866 }
3867
3868 /* Write all the constants in POOL. */
3869
3870 static void
3871 output_constant_pool_contents (struct rtx_constant_pool *pool)
3872 {
3873 struct constant_descriptor_rtx *desc;
3874
3875 for (desc = pool->first; desc ; desc = desc->next)
3876 if (desc->mark)
3877 {
3878 /* If the constant is part of an object_block, make sure that
3879 the constant has been positioned within its block, but do not
3880 write out its definition yet. output_object_blocks will do
3881 that later. */
3882 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
3883 && SYMBOL_REF_BLOCK (desc->sym))
3884 place_block_symbol (desc->sym);
3885 else
3886 {
3887 switch_to_section (targetm.asm_out.select_rtx_section
3888 (desc->mode, desc->constant, desc->align));
3889 output_constant_pool_1 (desc, desc->align);
3890 }
3891 }
3892 }
3893
3894 /* Mark all constants that are used in the current function, then write
3895 out the function's private constant pool. */
3896
3897 static void
3898 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
3899 tree fndecl ATTRIBUTE_UNUSED)
3900 {
3901 struct rtx_constant_pool *pool = crtl->varasm.pool;
3902
3903 /* It is possible for gcc to call force_const_mem and then to later
3904 discard the instructions which refer to the constant. In such a
3905 case we do not need to output the constant. */
3906 mark_constant_pool ();
3907
3908 #ifdef ASM_OUTPUT_POOL_PROLOGUE
3909 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
3910 #endif
3911
3912 output_constant_pool_contents (pool);
3913
3914 #ifdef ASM_OUTPUT_POOL_EPILOGUE
3915 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
3916 #endif
3917 }
3918 \f
3919 /* Write the contents of the shared constant pool. */
3920
3921 void
3922 output_shared_constant_pool (void)
3923 {
3924 output_constant_pool_contents (shared_constant_pool);
3925 }
3926 \f
3927 /* Determine what kind of relocations EXP may need. */
3928
3929 int
3930 compute_reloc_for_constant (tree exp)
3931 {
3932 int reloc = 0, reloc2;
3933 tree tem;
3934
3935 switch (TREE_CODE (exp))
3936 {
3937 case ADDR_EXPR:
3938 case FDESC_EXPR:
3939 /* Go inside any operations that get_inner_reference can handle and see
3940 if what's inside is a constant: no need to do anything here for
3941 addresses of variables or functions. */
3942 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
3943 tem = TREE_OPERAND (tem, 0))
3944 ;
3945
3946 if (TREE_CODE (tem) == MEM_REF
3947 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
3948 {
3949 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
3950 break;
3951 }
3952
3953 if (TREE_PUBLIC (tem))
3954 reloc |= 2;
3955 else
3956 reloc |= 1;
3957 break;
3958
3959 case PLUS_EXPR:
3960 case POINTER_PLUS_EXPR:
3961 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3962 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
3963 break;
3964
3965 case MINUS_EXPR:
3966 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3967 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
3968 /* The difference of two local labels is computable at link time. */
3969 if (reloc == 1 && reloc2 == 1)
3970 reloc = 0;
3971 else
3972 reloc |= reloc2;
3973 break;
3974
3975 CASE_CONVERT:
3976 case VIEW_CONVERT_EXPR:
3977 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3978 break;
3979
3980 case CONSTRUCTOR:
3981 {
3982 unsigned HOST_WIDE_INT idx;
3983 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
3984 if (tem != 0)
3985 reloc |= compute_reloc_for_constant (tem);
3986 }
3987 break;
3988
3989 default:
3990 break;
3991 }
3992 return reloc;
3993 }
3994
3995 /* Find all the constants whose addresses are referenced inside of EXP,
3996 and make sure assembler code with a label has been output for each one.
3997 Indicate whether an ADDR_EXPR has been encountered. */
3998
3999 static void
4000 output_addressed_constants (tree exp)
4001 {
4002 tree tem;
4003
4004 switch (TREE_CODE (exp))
4005 {
4006 case ADDR_EXPR:
4007 case FDESC_EXPR:
4008 /* Go inside any operations that get_inner_reference can handle and see
4009 if what's inside is a constant: no need to do anything here for
4010 addresses of variables or functions. */
4011 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4012 tem = TREE_OPERAND (tem, 0))
4013 ;
4014
4015 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4016 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4017 tem = DECL_INITIAL (tem);
4018
4019 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4020 output_constant_def (tem, 0);
4021
4022 if (TREE_CODE (tem) == MEM_REF)
4023 output_addressed_constants (TREE_OPERAND (tem, 0));
4024 break;
4025
4026 case PLUS_EXPR:
4027 case POINTER_PLUS_EXPR:
4028 case MINUS_EXPR:
4029 output_addressed_constants (TREE_OPERAND (exp, 1));
4030 /* Fall through. */
4031
4032 CASE_CONVERT:
4033 case VIEW_CONVERT_EXPR:
4034 output_addressed_constants (TREE_OPERAND (exp, 0));
4035 break;
4036
4037 case CONSTRUCTOR:
4038 {
4039 unsigned HOST_WIDE_INT idx;
4040 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4041 if (tem != 0)
4042 output_addressed_constants (tem);
4043 }
4044 break;
4045
4046 default:
4047 break;
4048 }
4049 }
4050 \f
4051 /* Whether a constructor CTOR is a valid static constant initializer if all
4052 its elements are. This used to be internal to initializer_constant_valid_p
4053 and has been exposed to let other functions like categorize_ctor_elements
4054 evaluate the property while walking a constructor for other purposes. */
4055
4056 bool
4057 constructor_static_from_elts_p (const_tree ctor)
4058 {
4059 return (TREE_CONSTANT (ctor)
4060 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4061 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4062 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4063 }
4064
4065 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4066 tree *cache);
4067
4068 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4069 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4070 which are valid when ENDTYPE is an integer of any size; in
4071 particular, this does not accept a pointer minus a constant. This
4072 returns null_pointer_node if the VALUE is an absolute constant
4073 which can be used to initialize a static variable. Otherwise it
4074 returns NULL. */
4075
4076 static tree
4077 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4078 {
4079 tree op0, op1;
4080
4081 if (!INTEGRAL_TYPE_P (endtype))
4082 return NULL_TREE;
4083
4084 op0 = TREE_OPERAND (value, 0);
4085 op1 = TREE_OPERAND (value, 1);
4086
4087 /* Like STRIP_NOPS except allow the operand mode to widen. This
4088 works around a feature of fold that simplifies (int)(p1 - p2) to
4089 ((int)p1 - (int)p2) under the theory that the narrower operation
4090 is cheaper. */
4091
4092 while (CONVERT_EXPR_P (op0)
4093 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4094 {
4095 tree inner = TREE_OPERAND (op0, 0);
4096 if (inner == error_mark_node
4097 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4098 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
4099 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4100 break;
4101 op0 = inner;
4102 }
4103
4104 while (CONVERT_EXPR_P (op1)
4105 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4106 {
4107 tree inner = TREE_OPERAND (op1, 0);
4108 if (inner == error_mark_node
4109 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4110 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
4111 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4112 break;
4113 op1 = inner;
4114 }
4115
4116 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4117 if (!op0)
4118 return NULL_TREE;
4119
4120 op1 = initializer_constant_valid_p_1 (op1, endtype,
4121 cache ? cache + 2 : NULL);
4122 /* Both initializers must be known. */
4123 if (op1)
4124 {
4125 if (op0 == op1
4126 && (op0 == null_pointer_node
4127 || TREE_CODE (value) == MINUS_EXPR))
4128 return null_pointer_node;
4129
4130 /* Support differences between labels. */
4131 if (TREE_CODE (op0) == LABEL_DECL
4132 && TREE_CODE (op1) == LABEL_DECL)
4133 return null_pointer_node;
4134
4135 if (TREE_CODE (op0) == STRING_CST
4136 && TREE_CODE (op1) == STRING_CST
4137 && operand_equal_p (op0, op1, 1))
4138 return null_pointer_node;
4139 }
4140
4141 return NULL_TREE;
4142 }
4143
4144 /* Helper function of initializer_constant_valid_p.
4145 Return nonzero if VALUE is a valid constant-valued expression
4146 for use in initializing a static variable; one that can be an
4147 element of a "constant" initializer.
4148
4149 Return null_pointer_node if the value is absolute;
4150 if it is relocatable, return the variable that determines the relocation.
4151 We assume that VALUE has been folded as much as possible;
4152 therefore, we do not need to check for such things as
4153 arithmetic-combinations of integers.
4154
4155 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4156
4157 static tree
4158 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4159 {
4160 tree ret;
4161
4162 switch (TREE_CODE (value))
4163 {
4164 case CONSTRUCTOR:
4165 if (constructor_static_from_elts_p (value))
4166 {
4167 unsigned HOST_WIDE_INT idx;
4168 tree elt;
4169 bool absolute = true;
4170
4171 if (cache && cache[0] == value)
4172 return cache[1];
4173 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4174 {
4175 tree reloc;
4176 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4177 NULL);
4178 if (!reloc)
4179 {
4180 if (cache)
4181 {
4182 cache[0] = value;
4183 cache[1] = NULL_TREE;
4184 }
4185 return NULL_TREE;
4186 }
4187 if (reloc != null_pointer_node)
4188 absolute = false;
4189 }
4190 /* For a non-absolute relocation, there is no single
4191 variable that can be "the variable that determines the
4192 relocation." */
4193 if (cache)
4194 {
4195 cache[0] = value;
4196 cache[1] = absolute ? null_pointer_node : error_mark_node;
4197 }
4198 return absolute ? null_pointer_node : error_mark_node;
4199 }
4200
4201 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4202
4203 case INTEGER_CST:
4204 case VECTOR_CST:
4205 case REAL_CST:
4206 case FIXED_CST:
4207 case STRING_CST:
4208 case COMPLEX_CST:
4209 return null_pointer_node;
4210
4211 case ADDR_EXPR:
4212 case FDESC_EXPR:
4213 {
4214 tree op0 = staticp (TREE_OPERAND (value, 0));
4215 if (op0)
4216 {
4217 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4218 to be a constant, this is old-skool offsetof-like nonsense. */
4219 if (TREE_CODE (op0) == INDIRECT_REF
4220 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4221 return null_pointer_node;
4222 /* Taking the address of a nested function involves a trampoline,
4223 unless we don't need or want one. */
4224 if (TREE_CODE (op0) == FUNCTION_DECL
4225 && DECL_STATIC_CHAIN (op0)
4226 && !TREE_NO_TRAMPOLINE (value))
4227 return NULL_TREE;
4228 /* "&{...}" requires a temporary to hold the constructed
4229 object. */
4230 if (TREE_CODE (op0) == CONSTRUCTOR)
4231 return NULL_TREE;
4232 }
4233 return op0;
4234 }
4235
4236 case NON_LVALUE_EXPR:
4237 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4238 endtype, cache);
4239
4240 case VIEW_CONVERT_EXPR:
4241 {
4242 tree src = TREE_OPERAND (value, 0);
4243 tree src_type = TREE_TYPE (src);
4244 tree dest_type = TREE_TYPE (value);
4245
4246 /* Allow view-conversions from aggregate to non-aggregate type only
4247 if the bit pattern is fully preserved afterwards; otherwise, the
4248 RTL expander won't be able to apply a subsequent transformation
4249 to the underlying constructor. */
4250 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4251 {
4252 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4253 return initializer_constant_valid_p_1 (src, endtype, cache);
4254 else
4255 return NULL_TREE;
4256 }
4257
4258 /* Allow all other kinds of view-conversion. */
4259 return initializer_constant_valid_p_1 (src, endtype, cache);
4260 }
4261
4262 CASE_CONVERT:
4263 {
4264 tree src = TREE_OPERAND (value, 0);
4265 tree src_type = TREE_TYPE (src);
4266 tree dest_type = TREE_TYPE (value);
4267
4268 /* Allow conversions between pointer types, floating-point
4269 types, and offset types. */
4270 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4271 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4272 || (TREE_CODE (dest_type) == OFFSET_TYPE
4273 && TREE_CODE (src_type) == OFFSET_TYPE))
4274 return initializer_constant_valid_p_1 (src, endtype, cache);
4275
4276 /* Allow length-preserving conversions between integer types. */
4277 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4278 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4279 return initializer_constant_valid_p_1 (src, endtype, cache);
4280
4281 /* Allow conversions between other integer types only if
4282 explicit value. */
4283 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type))
4284 {
4285 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4286 if (inner == null_pointer_node)
4287 return null_pointer_node;
4288 break;
4289 }
4290
4291 /* Allow (int) &foo provided int is as wide as a pointer. */
4292 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4293 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4294 return initializer_constant_valid_p_1 (src, endtype, cache);
4295
4296 /* Likewise conversions from int to pointers, but also allow
4297 conversions from 0. */
4298 if ((POINTER_TYPE_P (dest_type)
4299 || TREE_CODE (dest_type) == OFFSET_TYPE)
4300 && INTEGRAL_TYPE_P (src_type))
4301 {
4302 if (TREE_CODE (src) == INTEGER_CST
4303 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4304 return null_pointer_node;
4305 if (integer_zerop (src))
4306 return null_pointer_node;
4307 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4308 return initializer_constant_valid_p_1 (src, endtype, cache);
4309 }
4310
4311 /* Allow conversions to struct or union types if the value
4312 inside is okay. */
4313 if (TREE_CODE (dest_type) == RECORD_TYPE
4314 || TREE_CODE (dest_type) == UNION_TYPE)
4315 return initializer_constant_valid_p_1 (src, endtype, cache);
4316 }
4317 break;
4318
4319 case POINTER_PLUS_EXPR:
4320 case PLUS_EXPR:
4321 /* Any valid floating-point constants will have been folded by now;
4322 with -frounding-math we hit this with addition of two constants. */
4323 if (TREE_CODE (endtype) == REAL_TYPE)
4324 return NULL_TREE;
4325 if (cache && cache[0] == value)
4326 return cache[1];
4327 if (! INTEGRAL_TYPE_P (endtype)
4328 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4329 {
4330 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4331 tree valid0
4332 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4333 endtype, ncache);
4334 tree valid1
4335 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4336 endtype, ncache + 2);
4337 /* If either term is absolute, use the other term's relocation. */
4338 if (valid0 == null_pointer_node)
4339 ret = valid1;
4340 else if (valid1 == null_pointer_node)
4341 ret = valid0;
4342 /* Support narrowing pointer differences. */
4343 else
4344 ret = narrowing_initializer_constant_valid_p (value, endtype,
4345 ncache);
4346 }
4347 else
4348 /* Support narrowing pointer differences. */
4349 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4350 if (cache)
4351 {
4352 cache[0] = value;
4353 cache[1] = ret;
4354 }
4355 return ret;
4356
4357 case MINUS_EXPR:
4358 if (TREE_CODE (endtype) == REAL_TYPE)
4359 return NULL_TREE;
4360 if (cache && cache[0] == value)
4361 return cache[1];
4362 if (! INTEGRAL_TYPE_P (endtype)
4363 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4364 {
4365 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4366 tree valid0
4367 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4368 endtype, ncache);
4369 tree valid1
4370 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4371 endtype, ncache + 2);
4372 /* Win if second argument is absolute. */
4373 if (valid1 == null_pointer_node)
4374 ret = valid0;
4375 /* Win if both arguments have the same relocation.
4376 Then the value is absolute. */
4377 else if (valid0 == valid1 && valid0 != 0)
4378 ret = null_pointer_node;
4379 /* Since GCC guarantees that string constants are unique in the
4380 generated code, a subtraction between two copies of the same
4381 constant string is absolute. */
4382 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4383 && valid1 && TREE_CODE (valid1) == STRING_CST
4384 && operand_equal_p (valid0, valid1, 1))
4385 ret = null_pointer_node;
4386 /* Support narrowing differences. */
4387 else
4388 ret = narrowing_initializer_constant_valid_p (value, endtype,
4389 ncache);
4390 }
4391 else
4392 /* Support narrowing differences. */
4393 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4394 if (cache)
4395 {
4396 cache[0] = value;
4397 cache[1] = ret;
4398 }
4399 return ret;
4400
4401 default:
4402 break;
4403 }
4404
4405 return NULL_TREE;
4406 }
4407
4408 /* Return nonzero if VALUE is a valid constant-valued expression
4409 for use in initializing a static variable; one that can be an
4410 element of a "constant" initializer.
4411
4412 Return null_pointer_node if the value is absolute;
4413 if it is relocatable, return the variable that determines the relocation.
4414 We assume that VALUE has been folded as much as possible;
4415 therefore, we do not need to check for such things as
4416 arithmetic-combinations of integers. */
4417 tree
4418 initializer_constant_valid_p (tree value, tree endtype)
4419 {
4420 return initializer_constant_valid_p_1 (value, endtype, NULL);
4421 }
4422 \f
4423 /* Return true if VALUE is a valid constant-valued expression
4424 for use in initializing a static bit-field; one that can be
4425 an element of a "constant" initializer. */
4426
4427 bool
4428 initializer_constant_valid_for_bitfield_p (tree value)
4429 {
4430 /* For bitfields we support integer constants or possibly nested aggregates
4431 of such. */
4432 switch (TREE_CODE (value))
4433 {
4434 case CONSTRUCTOR:
4435 {
4436 unsigned HOST_WIDE_INT idx;
4437 tree elt;
4438
4439 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4440 if (!initializer_constant_valid_for_bitfield_p (elt))
4441 return false;
4442 return true;
4443 }
4444
4445 case INTEGER_CST:
4446 case REAL_CST:
4447 return true;
4448
4449 case VIEW_CONVERT_EXPR:
4450 case NON_LVALUE_EXPR:
4451 return
4452 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4453
4454 default:
4455 break;
4456 }
4457
4458 return false;
4459 }
4460
4461 /* output_constructor outer state of relevance in recursive calls, typically
4462 for nested aggregate bitfields. */
4463
4464 typedef struct {
4465 unsigned int bit_offset; /* current position in ... */
4466 int byte; /* ... the outer byte buffer. */
4467 } oc_outer_state;
4468
4469 static unsigned HOST_WIDE_INT
4470 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int,
4471 oc_outer_state *);
4472
4473 /* Output assembler code for constant EXP to FILE, with no label.
4474 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4475 Assumes output_addressed_constants has been done on EXP already.
4476
4477 Generate exactly SIZE bytes of assembler data, padding at the end
4478 with zeros if necessary. SIZE must always be specified.
4479
4480 SIZE is important for structure constructors,
4481 since trailing members may have been omitted from the constructor.
4482 It is also important for initialization of arrays from string constants
4483 since the full length of the string constant might not be wanted.
4484 It is also needed for initialization of unions, where the initializer's
4485 type is just one member, and that may not be as long as the union.
4486
4487 There a case in which we would fail to output exactly SIZE bytes:
4488 for a structure constructor that wants to produce more than SIZE bytes.
4489 But such constructors will never be generated for any possible input.
4490
4491 ALIGN is the alignment of the data in bits. */
4492
4493 void
4494 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align)
4495 {
4496 enum tree_code code;
4497 unsigned HOST_WIDE_INT thissize;
4498
4499 if (size == 0 || flag_syntax_only)
4500 return;
4501
4502 /* See if we're trying to initialize a pointer in a non-default mode
4503 to the address of some declaration somewhere. If the target says
4504 the mode is valid for pointers, assume the target has a way of
4505 resolving it. */
4506 if (TREE_CODE (exp) == NOP_EXPR
4507 && POINTER_TYPE_P (TREE_TYPE (exp))
4508 && targetm.addr_space.valid_pointer_mode
4509 (TYPE_MODE (TREE_TYPE (exp)),
4510 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4511 {
4512 tree saved_type = TREE_TYPE (exp);
4513
4514 /* Peel off any intermediate conversions-to-pointer for valid
4515 pointer modes. */
4516 while (TREE_CODE (exp) == NOP_EXPR
4517 && POINTER_TYPE_P (TREE_TYPE (exp))
4518 && targetm.addr_space.valid_pointer_mode
4519 (TYPE_MODE (TREE_TYPE (exp)),
4520 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4521 exp = TREE_OPERAND (exp, 0);
4522
4523 /* If what we're left with is the address of something, we can
4524 convert the address to the final type and output it that
4525 way. */
4526 if (TREE_CODE (exp) == ADDR_EXPR)
4527 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4528 /* Likewise for constant ints. */
4529 else if (TREE_CODE (exp) == INTEGER_CST)
4530 exp = build_int_cst_wide (saved_type, TREE_INT_CST_LOW (exp),
4531 TREE_INT_CST_HIGH (exp));
4532
4533 }
4534
4535 /* Eliminate any conversions since we'll be outputting the underlying
4536 constant. */
4537 while (CONVERT_EXPR_P (exp)
4538 || TREE_CODE (exp) == NON_LVALUE_EXPR
4539 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4540 {
4541 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4542 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4543
4544 /* Make sure eliminating the conversion is really a no-op, except with
4545 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4546 union types to allow for Ada unchecked unions. */
4547 if (type_size > op_size
4548 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4549 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4550 /* Keep the conversion. */
4551 break;
4552 else
4553 exp = TREE_OPERAND (exp, 0);
4554 }
4555
4556 code = TREE_CODE (TREE_TYPE (exp));
4557 thissize = int_size_in_bytes (TREE_TYPE (exp));
4558
4559 /* Allow a constructor with no elements for any data type.
4560 This means to fill the space with zeros. */
4561 if (TREE_CODE (exp) == CONSTRUCTOR
4562 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4563 {
4564 assemble_zeros (size);
4565 return;
4566 }
4567
4568 if (TREE_CODE (exp) == FDESC_EXPR)
4569 {
4570 #ifdef ASM_OUTPUT_FDESC
4571 HOST_WIDE_INT part = tree_low_cst (TREE_OPERAND (exp, 1), 0);
4572 tree decl = TREE_OPERAND (exp, 0);
4573 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4574 #else
4575 gcc_unreachable ();
4576 #endif
4577 return;
4578 }
4579
4580 /* Now output the underlying data. If we've handling the padding, return.
4581 Otherwise, break and ensure SIZE is the size written. */
4582 switch (code)
4583 {
4584 case BOOLEAN_TYPE:
4585 case INTEGER_TYPE:
4586 case ENUMERAL_TYPE:
4587 case POINTER_TYPE:
4588 case REFERENCE_TYPE:
4589 case OFFSET_TYPE:
4590 case FIXED_POINT_TYPE:
4591 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
4592 EXPAND_INITIALIZER),
4593 MIN (size, thissize), align, 0))
4594 error ("initializer for integer/fixed-point value is too complicated");
4595 break;
4596
4597 case REAL_TYPE:
4598 if (TREE_CODE (exp) != REAL_CST)
4599 error ("initializer for floating value is not a floating constant");
4600 else
4601 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)), align);
4602 break;
4603
4604 case COMPLEX_TYPE:
4605 output_constant (TREE_REALPART (exp), thissize / 2, align);
4606 output_constant (TREE_IMAGPART (exp), thissize / 2,
4607 min_align (align, BITS_PER_UNIT * (thissize / 2)));
4608 break;
4609
4610 case ARRAY_TYPE:
4611 case VECTOR_TYPE:
4612 switch (TREE_CODE (exp))
4613 {
4614 case CONSTRUCTOR:
4615 output_constructor (exp, size, align, NULL);
4616 return;
4617 case STRING_CST:
4618 thissize
4619 = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4620 assemble_string (TREE_STRING_POINTER (exp), thissize);
4621 break;
4622 case VECTOR_CST:
4623 {
4624 enum machine_mode inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4625 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4626 int elt_size = GET_MODE_SIZE (inner);
4627 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align);
4628 thissize = elt_size;
4629 for (unsigned int i = 1; i < VECTOR_CST_NELTS (exp); i++)
4630 {
4631 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign);
4632 thissize += elt_size;
4633 }
4634 break;
4635 }
4636 default:
4637 gcc_unreachable ();
4638 }
4639 break;
4640
4641 case RECORD_TYPE:
4642 case UNION_TYPE:
4643 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4644 output_constructor (exp, size, align, NULL);
4645 return;
4646
4647 case ERROR_MARK:
4648 return;
4649
4650 default:
4651 gcc_unreachable ();
4652 }
4653
4654 if (size > thissize)
4655 assemble_zeros (size - thissize);
4656 }
4657
4658 \f
4659 /* Subroutine of output_constructor, used for computing the size of
4660 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4661 type with an unspecified upper bound. */
4662
4663 static unsigned HOST_WIDE_INT
4664 array_size_for_constructor (tree val)
4665 {
4666 tree max_index;
4667 unsigned HOST_WIDE_INT cnt;
4668 tree index, value, tmp;
4669 double_int i;
4670
4671 /* This code used to attempt to handle string constants that are not
4672 arrays of single-bytes, but nothing else does, so there's no point in
4673 doing it here. */
4674 if (TREE_CODE (val) == STRING_CST)
4675 return TREE_STRING_LENGTH (val);
4676
4677 max_index = NULL_TREE;
4678 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
4679 {
4680 if (TREE_CODE (index) == RANGE_EXPR)
4681 index = TREE_OPERAND (index, 1);
4682 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
4683 max_index = index;
4684 }
4685
4686 if (max_index == NULL_TREE)
4687 return 0;
4688
4689 /* Compute the total number of array elements. */
4690 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
4691 i = tree_to_double_int (max_index) - tree_to_double_int (tmp);
4692 i += double_int_one;
4693
4694 /* Multiply by the array element unit size to find number of bytes. */
4695 i *= tree_to_double_int (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
4696
4697 gcc_assert (i.fits_uhwi ());
4698 return i.low;
4699 }
4700
4701 /* Other datastructures + helpers for output_constructor. */
4702
4703 /* output_constructor local state to support interaction with helpers. */
4704
4705 typedef struct {
4706
4707 /* Received arguments. */
4708 tree exp; /* Constructor expression. */
4709 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */
4710 unsigned int align; /* Known initial alignment. */
4711
4712 /* Constructor expression data. */
4713 tree type; /* Expression type. */
4714 tree field; /* Current field decl in a record. */
4715 tree min_index; /* Lower bound if specified for an array. */
4716
4717 /* Output processing state. */
4718 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */
4719 bool byte_buffer_in_use; /* Whether byte ... */
4720 int byte; /* ... contains part of a bitfield byte yet to
4721 be output. */
4722
4723 int last_relative_index; /* Implicit or explicit index of the last
4724 array element output within a bitfield. */
4725 /* Current element. */
4726 tree val; /* Current element value. */
4727 tree index; /* Current element index. */
4728
4729 } oc_local_state;
4730
4731 /* Helper for output_constructor. From the current LOCAL state, output a
4732 RANGE_EXPR element. */
4733
4734 static void
4735 output_constructor_array_range (oc_local_state *local)
4736 {
4737 unsigned HOST_WIDE_INT fieldsize
4738 = int_size_in_bytes (TREE_TYPE (local->type));
4739
4740 HOST_WIDE_INT lo_index
4741 = tree_low_cst (TREE_OPERAND (local->index, 0), 0);
4742 HOST_WIDE_INT hi_index
4743 = tree_low_cst (TREE_OPERAND (local->index, 1), 0);
4744 HOST_WIDE_INT index;
4745
4746 unsigned int align2
4747 = min_align (local->align, fieldsize * BITS_PER_UNIT);
4748
4749 for (index = lo_index; index <= hi_index; index++)
4750 {
4751 /* Output the element's initial value. */
4752 if (local->val == NULL_TREE)
4753 assemble_zeros (fieldsize);
4754 else
4755 output_constant (local->val, fieldsize, align2);
4756
4757 /* Count its size. */
4758 local->total_bytes += fieldsize;
4759 }
4760 }
4761
4762 /* Helper for output_constructor. From the current LOCAL state, output a
4763 field element that is not true bitfield or part of an outer one. */
4764
4765 static void
4766 output_constructor_regular_field (oc_local_state *local)
4767 {
4768 /* Field size and position. Since this structure is static, we know the
4769 positions are constant. */
4770 unsigned HOST_WIDE_INT fieldsize;
4771 HOST_WIDE_INT fieldpos;
4772
4773 unsigned int align2;
4774
4775 if (local->index != NULL_TREE)
4776 {
4777 /* Perform the index calculation in modulo arithmetic but
4778 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
4779 but we are using an unsigned sizetype. */
4780 unsigned prec = TYPE_PRECISION (sizetype);
4781 double_int idx = tree_to_double_int (local->index)
4782 - tree_to_double_int (local->min_index);
4783 idx = idx.sext (prec);
4784 fieldpos = (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (local->val)), 1)
4785 * idx.low);
4786 }
4787 else if (local->field != NULL_TREE)
4788 fieldpos = int_byte_position (local->field);
4789 else
4790 fieldpos = 0;
4791
4792 /* Output any buffered-up bit-fields preceding this element. */
4793 if (local->byte_buffer_in_use)
4794 {
4795 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4796 local->total_bytes++;
4797 local->byte_buffer_in_use = false;
4798 }
4799
4800 /* Advance to offset of this element.
4801 Note no alignment needed in an array, since that is guaranteed
4802 if each element has the proper size. */
4803 if ((local->field != NULL_TREE || local->index != NULL_TREE)
4804 && fieldpos != local->total_bytes)
4805 {
4806 gcc_assert (fieldpos >= local->total_bytes);
4807 assemble_zeros (fieldpos - local->total_bytes);
4808 local->total_bytes = fieldpos;
4809 }
4810
4811 /* Find the alignment of this element. */
4812 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
4813
4814 /* Determine size this element should occupy. */
4815 if (local->field)
4816 {
4817 fieldsize = 0;
4818
4819 /* If this is an array with an unspecified upper bound,
4820 the initializer determines the size. */
4821 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
4822 but we cannot do this until the deprecated support for
4823 initializing zero-length array members is removed. */
4824 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
4825 && TYPE_DOMAIN (TREE_TYPE (local->field))
4826 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field))))
4827 {
4828 fieldsize = array_size_for_constructor (local->val);
4829 /* Given a non-empty initialization, this field had
4830 better be last. */
4831 gcc_assert (!fieldsize || !DECL_CHAIN (local->field));
4832 }
4833 else
4834 fieldsize = tree_low_cst (DECL_SIZE_UNIT (local->field), 1);
4835 }
4836 else
4837 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
4838
4839 /* Output the element's initial value. */
4840 if (local->val == NULL_TREE)
4841 assemble_zeros (fieldsize);
4842 else
4843 output_constant (local->val, fieldsize, align2);
4844
4845 /* Count its size. */
4846 local->total_bytes += fieldsize;
4847 }
4848
4849 /* Helper for output_constructor. From the current LOCAL and OUTER states,
4850 output an element that is a true bitfield or part of an outer one. */
4851
4852 static void
4853 output_constructor_bitfield (oc_local_state *local, oc_outer_state *outer)
4854 {
4855 /* Bit size of this element. */
4856 HOST_WIDE_INT ebitsize
4857 = (local->field
4858 ? tree_low_cst (DECL_SIZE (local->field), 1)
4859 : tree_low_cst (TYPE_SIZE (TREE_TYPE (local->type)), 1));
4860
4861 /* Relative index of this element if this is an array component. */
4862 HOST_WIDE_INT relative_index
4863 = (!local->field
4864 ? (local->index
4865 ? (tree_low_cst (local->index, 0)
4866 - tree_low_cst (local->min_index, 0))
4867 : local->last_relative_index + 1)
4868 : 0);
4869
4870 /* Bit position of this element from the start of the containing
4871 constructor. */
4872 HOST_WIDE_INT constructor_relative_ebitpos
4873 = (local->field
4874 ? int_bit_position (local->field)
4875 : ebitsize * relative_index);
4876
4877 /* Bit position of this element from the start of a possibly ongoing
4878 outer byte buffer. */
4879 HOST_WIDE_INT byte_relative_ebitpos
4880 = ((outer ? outer->bit_offset : 0) + constructor_relative_ebitpos);
4881
4882 /* From the start of a possibly ongoing outer byte buffer, offsets to
4883 the first bit of this element and to the first bit past the end of
4884 this element. */
4885 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
4886 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
4887
4888 local->last_relative_index = relative_index;
4889
4890 if (local->val == NULL_TREE)
4891 local->val = integer_zero_node;
4892
4893 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
4894 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
4895 local->val = TREE_OPERAND (local->val, 0);
4896
4897 if (TREE_CODE (local->val) != INTEGER_CST
4898 && TREE_CODE (local->val) != CONSTRUCTOR)
4899 {
4900 error ("invalid initial value for member %qE", DECL_NAME (local->field));
4901 return;
4902 }
4903
4904 /* If this field does not start in this (or, next) byte,
4905 skip some bytes. */
4906 if (next_offset / BITS_PER_UNIT != local->total_bytes)
4907 {
4908 /* Output remnant of any bit field in previous bytes. */
4909 if (local->byte_buffer_in_use)
4910 {
4911 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4912 local->total_bytes++;
4913 local->byte_buffer_in_use = false;
4914 }
4915
4916 /* If still not at proper byte, advance to there. */
4917 if (next_offset / BITS_PER_UNIT != local->total_bytes)
4918 {
4919 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
4920 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
4921 local->total_bytes = next_offset / BITS_PER_UNIT;
4922 }
4923 }
4924
4925 /* Set up the buffer if necessary. */
4926 if (!local->byte_buffer_in_use)
4927 {
4928 local->byte = 0;
4929 if (ebitsize > 0)
4930 local->byte_buffer_in_use = true;
4931 }
4932
4933 /* If this is nested constructor, recurse passing the bit offset and the
4934 pending data, then retrieve the new pending data afterwards. */
4935 if (TREE_CODE (local->val) == CONSTRUCTOR)
4936 {
4937 oc_outer_state output_state;
4938
4939 output_state.bit_offset = next_offset % BITS_PER_UNIT;
4940 output_state.byte = local->byte;
4941 local->total_bytes
4942 += output_constructor (local->val, 0, 0, &output_state);
4943 local->byte = output_state.byte;
4944 return;
4945 }
4946
4947 /* Otherwise, we must split the element into pieces that fall within
4948 separate bytes, and combine each byte with previous or following
4949 bit-fields. */
4950 while (next_offset < end_offset)
4951 {
4952 int this_time;
4953 int shift;
4954 HOST_WIDE_INT value;
4955 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
4956 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
4957
4958 /* Advance from byte to byte
4959 within this element when necessary. */
4960 while (next_byte != local->total_bytes)
4961 {
4962 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4963 local->total_bytes++;
4964 local->byte = 0;
4965 }
4966
4967 /* Number of bits we can process at once
4968 (all part of the same byte). */
4969 this_time = MIN (end_offset - next_offset,
4970 BITS_PER_UNIT - next_bit);
4971 if (BYTES_BIG_ENDIAN)
4972 {
4973 /* On big-endian machine, take the most significant bits
4974 first (of the bits that are significant)
4975 and put them into bytes from the most significant end. */
4976 shift = end_offset - next_offset - this_time;
4977
4978 /* Don't try to take a bunch of bits that cross
4979 the word boundary in the INTEGER_CST. We can
4980 only select bits from the LOW or HIGH part
4981 not from both. */
4982 if (shift < HOST_BITS_PER_WIDE_INT
4983 && shift + this_time > HOST_BITS_PER_WIDE_INT)
4984 {
4985 this_time = shift + this_time - HOST_BITS_PER_WIDE_INT;
4986 shift = HOST_BITS_PER_WIDE_INT;
4987 }
4988
4989 /* Now get the bits from the appropriate constant word. */
4990 if (shift < HOST_BITS_PER_WIDE_INT)
4991 value = TREE_INT_CST_LOW (local->val);
4992 else
4993 {
4994 gcc_assert (shift < HOST_BITS_PER_DOUBLE_INT);
4995 value = TREE_INT_CST_HIGH (local->val);
4996 shift -= HOST_BITS_PER_WIDE_INT;
4997 }
4998
4999 /* Get the result. This works only when:
5000 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5001 local->byte |= (((value >> shift)
5002 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5003 << (BITS_PER_UNIT - this_time - next_bit));
5004 }
5005 else
5006 {
5007 /* On little-endian machines,
5008 take first the least significant bits of the value
5009 and pack them starting at the least significant
5010 bits of the bytes. */
5011 shift = next_offset - byte_relative_ebitpos;
5012
5013 /* Don't try to take a bunch of bits that cross
5014 the word boundary in the INTEGER_CST. We can
5015 only select bits from the LOW or HIGH part
5016 not from both. */
5017 if (shift < HOST_BITS_PER_WIDE_INT
5018 && shift + this_time > HOST_BITS_PER_WIDE_INT)
5019 this_time = (HOST_BITS_PER_WIDE_INT - shift);
5020
5021 /* Now get the bits from the appropriate constant word. */
5022 if (shift < HOST_BITS_PER_WIDE_INT)
5023 value = TREE_INT_CST_LOW (local->val);
5024 else
5025 {
5026 gcc_assert (shift < HOST_BITS_PER_DOUBLE_INT);
5027 value = TREE_INT_CST_HIGH (local->val);
5028 shift -= HOST_BITS_PER_WIDE_INT;
5029 }
5030
5031 /* Get the result. This works only when:
5032 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5033 local->byte |= (((value >> shift)
5034 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5035 << next_bit);
5036 }
5037
5038 next_offset += this_time;
5039 local->byte_buffer_in_use = true;
5040 }
5041 }
5042
5043 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5044 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5045 caller output state of relevance in recursive invocations. */
5046
5047 static unsigned HOST_WIDE_INT
5048 output_constructor (tree exp, unsigned HOST_WIDE_INT size,
5049 unsigned int align, oc_outer_state * outer)
5050 {
5051 unsigned HOST_WIDE_INT cnt;
5052 constructor_elt *ce;
5053
5054 oc_local_state local;
5055
5056 /* Setup our local state to communicate with helpers. */
5057 local.exp = exp;
5058 local.size = size;
5059 local.align = align;
5060
5061 local.total_bytes = 0;
5062 local.byte_buffer_in_use = outer != NULL;
5063 local.byte = outer ? outer->byte : 0;
5064
5065 local.type = TREE_TYPE (exp);
5066
5067 local.last_relative_index = -1;
5068
5069 local.min_index = NULL_TREE;
5070 if (TREE_CODE (local.type) == ARRAY_TYPE
5071 && TYPE_DOMAIN (local.type) != NULL_TREE)
5072 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5073
5074 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5075
5076 /* As CE goes through the elements of the constant, FIELD goes through the
5077 structure fields if the constant is a structure. If the constant is a
5078 union, we override this by getting the field from the TREE_LIST element.
5079 But the constant could also be an array. Then FIELD is zero.
5080
5081 There is always a maximum of one element in the chain LINK for unions
5082 (even if the initializer in a source program incorrectly contains
5083 more one). */
5084
5085 local.field = NULL_TREE;
5086 if (TREE_CODE (local.type) == RECORD_TYPE)
5087 local.field = TYPE_FIELDS (local.type);
5088
5089 for (cnt = 0;
5090 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5091 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5092 {
5093 local.val = ce->value;
5094 local.index = NULL_TREE;
5095
5096 /* The element in a union constructor specifies the proper field
5097 or index. */
5098 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5099 local.field = ce->index;
5100
5101 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5102 local.index = ce->index;
5103
5104 if (local.field && flag_verbose_asm)
5105 fprintf (asm_out_file, "%s %s:\n",
5106 ASM_COMMENT_START,
5107 DECL_NAME (local.field)
5108 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5109 : "<anonymous>");
5110
5111 /* Eliminate the marker that makes a cast not be an lvalue. */
5112 if (local.val != NULL_TREE)
5113 STRIP_NOPS (local.val);
5114
5115 /* Output the current element, using the appropriate helper ... */
5116
5117 /* For an array slice not part of an outer bitfield. */
5118 if (!outer
5119 && local.index != NULL_TREE
5120 && TREE_CODE (local.index) == RANGE_EXPR)
5121 output_constructor_array_range (&local);
5122
5123 /* For a field that is neither a true bitfield nor part of an outer one,
5124 known to be at least byte aligned and multiple-of-bytes long. */
5125 else if (!outer
5126 && (local.field == NULL_TREE
5127 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5128 output_constructor_regular_field (&local);
5129
5130 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5131 supported for scalar fields, so we may need to convert first. */
5132 else
5133 {
5134 if (TREE_CODE (local.val) == REAL_CST)
5135 local.val
5136 = fold_unary (VIEW_CONVERT_EXPR,
5137 build_nonstandard_integer_type
5138 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5139 local.val);
5140 output_constructor_bitfield (&local, outer);
5141 }
5142 }
5143
5144 /* If we are not at toplevel, save the pending data for our caller.
5145 Otherwise output the pending data and padding zeros as needed. */
5146 if (outer)
5147 outer->byte = local.byte;
5148 else
5149 {
5150 if (local.byte_buffer_in_use)
5151 {
5152 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5153 local.total_bytes++;
5154 }
5155
5156 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5157 {
5158 assemble_zeros (local.size - local.total_bytes);
5159 local.total_bytes = local.size;
5160 }
5161 }
5162
5163 return local.total_bytes;
5164 }
5165
5166 /* Mark DECL as weak. */
5167
5168 static void
5169 mark_weak (tree decl)
5170 {
5171 DECL_WEAK (decl) = 1;
5172
5173 if (DECL_RTL_SET_P (decl)
5174 && MEM_P (DECL_RTL (decl))
5175 && XEXP (DECL_RTL (decl), 0)
5176 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5177 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5178 }
5179
5180 /* Merge weak status between NEWDECL and OLDDECL. */
5181
5182 void
5183 merge_weak (tree newdecl, tree olddecl)
5184 {
5185 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5186 {
5187 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5188 {
5189 tree *pwd;
5190 /* We put the NEWDECL on the weak_decls list at some point
5191 and OLDDECL as well. Keep just OLDDECL on the list. */
5192 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5193 if (TREE_VALUE (*pwd) == newdecl)
5194 {
5195 *pwd = TREE_CHAIN (*pwd);
5196 break;
5197 }
5198 }
5199 return;
5200 }
5201
5202 if (DECL_WEAK (newdecl))
5203 {
5204 tree wd;
5205
5206 /* NEWDECL is weak, but OLDDECL is not. */
5207
5208 /* If we already output the OLDDECL, we're in trouble; we can't
5209 go back and make it weak. This should never happen in
5210 unit-at-a-time compilation. */
5211 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5212
5213 /* If we've already generated rtl referencing OLDDECL, we may
5214 have done so in a way that will not function properly with
5215 a weak symbol. Again in unit-at-a-time this should be
5216 impossible. */
5217 gcc_assert (!TREE_USED (olddecl)
5218 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5219
5220 if (TARGET_SUPPORTS_WEAK)
5221 {
5222 /* We put the NEWDECL on the weak_decls list at some point.
5223 Replace it with the OLDDECL. */
5224 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5225 if (TREE_VALUE (wd) == newdecl)
5226 {
5227 TREE_VALUE (wd) = olddecl;
5228 break;
5229 }
5230 /* We may not find the entry on the list. If NEWDECL is a
5231 weak alias, then we will have already called
5232 globalize_decl to remove the entry; in that case, we do
5233 not need to do anything. */
5234 }
5235
5236 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5237 mark_weak (olddecl);
5238 }
5239 else
5240 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5241 weak. Just update NEWDECL to indicate that it's weak too. */
5242 mark_weak (newdecl);
5243 }
5244
5245 /* Declare DECL to be a weak symbol. */
5246
5247 void
5248 declare_weak (tree decl)
5249 {
5250 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5251 if (! TREE_PUBLIC (decl))
5252 error ("weak declaration of %q+D must be public", decl);
5253 else if (!TARGET_SUPPORTS_WEAK)
5254 warning (0, "weak declaration of %q+D not supported", decl);
5255
5256 mark_weak (decl);
5257 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5258 DECL_ATTRIBUTES (decl)
5259 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5260 }
5261
5262 static void
5263 weak_finish_1 (tree decl)
5264 {
5265 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5266 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5267 #endif
5268
5269 if (! TREE_USED (decl))
5270 return;
5271
5272 #ifdef ASM_WEAKEN_DECL
5273 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5274 #else
5275 #ifdef ASM_WEAKEN_LABEL
5276 ASM_WEAKEN_LABEL (asm_out_file, name);
5277 #else
5278 #ifdef ASM_OUTPUT_WEAK_ALIAS
5279 {
5280 static bool warn_once = 0;
5281 if (! warn_once)
5282 {
5283 warning (0, "only weak aliases are supported in this configuration");
5284 warn_once = 1;
5285 }
5286 return;
5287 }
5288 #endif
5289 #endif
5290 #endif
5291 }
5292
5293 /* Fiven an assembly name, find the decl it is associated with. */
5294 static tree
5295 find_decl (tree target)
5296 {
5297 symtab_node node = symtab_node_for_asm (target);
5298 if (node)
5299 return node->symbol.decl;
5300 return NULL_TREE;
5301 }
5302
5303 /* This TREE_LIST contains weakref targets. */
5304
5305 static GTY(()) tree weakref_targets;
5306
5307 /* Emit any pending weak declarations. */
5308
5309 void
5310 weak_finish (void)
5311 {
5312 tree t;
5313
5314 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5315 {
5316 tree alias_decl = TREE_PURPOSE (t);
5317 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5318
5319 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5320 /* Remove alias_decl from the weak list, but leave entries for
5321 the target alone. */
5322 target = NULL_TREE;
5323 #ifndef ASM_OUTPUT_WEAKREF
5324 else if (! TREE_SYMBOL_REFERENCED (target))
5325 {
5326 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5327 defined, otherwise we and weak_finish_1 would use
5328 different macros. */
5329 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5330 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5331 # else
5332 tree decl = find_decl (target);
5333
5334 if (! decl)
5335 {
5336 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5337 TREE_CODE (alias_decl), target,
5338 TREE_TYPE (alias_decl));
5339
5340 DECL_EXTERNAL (decl) = 1;
5341 TREE_PUBLIC (decl) = 1;
5342 DECL_ARTIFICIAL (decl) = 1;
5343 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5344 TREE_USED (decl) = 1;
5345 }
5346
5347 weak_finish_1 (decl);
5348 # endif
5349 }
5350 #endif
5351
5352 {
5353 tree *p;
5354 tree t2;
5355
5356 /* Remove the alias and the target from the pending weak list
5357 so that we do not emit any .weak directives for the former,
5358 nor multiple .weak directives for the latter. */
5359 for (p = &weak_decls; (t2 = *p) ; )
5360 {
5361 if (TREE_VALUE (t2) == alias_decl
5362 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5363 *p = TREE_CHAIN (t2);
5364 else
5365 p = &TREE_CHAIN (t2);
5366 }
5367
5368 /* Remove other weakrefs to the same target, to speed things up. */
5369 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5370 {
5371 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5372 *p = TREE_CHAIN (t2);
5373 else
5374 p = &TREE_CHAIN (t2);
5375 }
5376 }
5377 }
5378
5379 for (t = weak_decls; t; t = TREE_CHAIN (t))
5380 {
5381 tree decl = TREE_VALUE (t);
5382
5383 weak_finish_1 (decl);
5384 }
5385 }
5386
5387 /* Emit the assembly bits to indicate that DECL is globally visible. */
5388
5389 static void
5390 globalize_decl (tree decl)
5391 {
5392
5393 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5394 if (DECL_WEAK (decl))
5395 {
5396 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5397 tree *p, t;
5398
5399 #ifdef ASM_WEAKEN_DECL
5400 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5401 #else
5402 ASM_WEAKEN_LABEL (asm_out_file, name);
5403 #endif
5404
5405 /* Remove this function from the pending weak list so that
5406 we do not emit multiple .weak directives for it. */
5407 for (p = &weak_decls; (t = *p) ; )
5408 {
5409 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5410 *p = TREE_CHAIN (t);
5411 else
5412 p = &TREE_CHAIN (t);
5413 }
5414
5415 /* Remove weakrefs to the same target from the pending weakref
5416 list, for the same reason. */
5417 for (p = &weakref_targets; (t = *p) ; )
5418 {
5419 if (DECL_ASSEMBLER_NAME (decl)
5420 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5421 *p = TREE_CHAIN (t);
5422 else
5423 p = &TREE_CHAIN (t);
5424 }
5425
5426 return;
5427 }
5428 #endif
5429
5430 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5431 }
5432
5433 vec<alias_pair, va_gc> *alias_pairs;
5434
5435 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5436 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5437 tree node is DECL to have the value of the tree node TARGET. */
5438
5439 void
5440 do_assemble_alias (tree decl, tree target)
5441 {
5442 /* Emulated TLS had better not get this var. */
5443 gcc_assert(!(!targetm.have_tls
5444 && TREE_CODE (decl) == VAR_DECL
5445 && DECL_THREAD_LOCAL_P (decl)));
5446
5447 if (TREE_ASM_WRITTEN (decl))
5448 return;
5449
5450 /* We must force creation of DECL_RTL for debug info generation, even though
5451 we don't use it here. */
5452 make_decl_rtl (decl);
5453
5454 TREE_ASM_WRITTEN (decl) = 1;
5455 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5456
5457 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5458 {
5459 ultimate_transparent_alias_target (&target);
5460
5461 if (!TREE_SYMBOL_REFERENCED (target))
5462 weakref_targets = tree_cons (decl, target, weakref_targets);
5463
5464 #ifdef ASM_OUTPUT_WEAKREF
5465 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5466 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5467 IDENTIFIER_POINTER (target));
5468 #else
5469 if (!TARGET_SUPPORTS_WEAK)
5470 {
5471 error_at (DECL_SOURCE_LOCATION (decl),
5472 "weakref is not supported in this configuration");
5473 return;
5474 }
5475 #endif
5476 return;
5477 }
5478
5479 #ifdef ASM_OUTPUT_DEF
5480 /* Make name accessible from other files, if appropriate. */
5481
5482 if (TREE_PUBLIC (decl))
5483 {
5484 globalize_decl (decl);
5485 maybe_assemble_visibility (decl);
5486 }
5487 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5488 {
5489 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5490 if (targetm.has_ifunc_p ())
5491 ASM_OUTPUT_TYPE_DIRECTIVE
5492 (asm_out_file, IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5493 IFUNC_ASM_TYPE);
5494 else
5495 #endif
5496 error_at (DECL_SOURCE_LOCATION (decl),
5497 "ifunc is not supported on this target");
5498 }
5499
5500 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5501 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5502 # else
5503 ASM_OUTPUT_DEF (asm_out_file,
5504 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5505 IDENTIFIER_POINTER (target));
5506 # endif
5507 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5508 {
5509 const char *name;
5510 tree *p, t;
5511
5512 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5513 # ifdef ASM_WEAKEN_DECL
5514 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5515 # else
5516 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5517 # endif
5518 /* Remove this function from the pending weak list so that
5519 we do not emit multiple .weak directives for it. */
5520 for (p = &weak_decls; (t = *p) ; )
5521 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5522 *p = TREE_CHAIN (t);
5523 else
5524 p = &TREE_CHAIN (t);
5525
5526 /* Remove weakrefs to the same target from the pending weakref
5527 list, for the same reason. */
5528 for (p = &weakref_targets; (t = *p) ; )
5529 {
5530 if (DECL_ASSEMBLER_NAME (decl)
5531 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5532 *p = TREE_CHAIN (t);
5533 else
5534 p = &TREE_CHAIN (t);
5535 }
5536 }
5537 #endif
5538 }
5539
5540 /* Emit an assembler directive to make the symbol for DECL an alias to
5541 the symbol for TARGET. */
5542
5543 void
5544 assemble_alias (tree decl, tree target)
5545 {
5546 tree target_decl;
5547
5548 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5549 {
5550 tree alias = DECL_ASSEMBLER_NAME (decl);
5551
5552 ultimate_transparent_alias_target (&target);
5553
5554 if (alias == target)
5555 error ("weakref %q+D ultimately targets itself", decl);
5556 if (TREE_PUBLIC (decl))
5557 error ("weakref %q+D must have static linkage", decl);
5558 }
5559 else
5560 {
5561 #if !defined (ASM_OUTPUT_DEF)
5562 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5563 error_at (DECL_SOURCE_LOCATION (decl),
5564 "alias definitions not supported in this configuration");
5565 return;
5566 # else
5567 if (!DECL_WEAK (decl))
5568 {
5569 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5570 error_at (DECL_SOURCE_LOCATION (decl),
5571 "ifunc is not supported in this configuration");
5572 else
5573 error_at (DECL_SOURCE_LOCATION (decl),
5574 "only weak aliases are supported in this configuration");
5575 return;
5576 }
5577 # endif
5578 #endif
5579 }
5580 TREE_USED (decl) = 1;
5581
5582 /* Allow aliases to aliases. */
5583 if (TREE_CODE (decl) == FUNCTION_DECL)
5584 cgraph_get_create_node (decl)->symbol.alias = true;
5585 else
5586 varpool_node_for_decl (decl)->symbol.alias = true;
5587
5588 /* If the target has already been emitted, we don't have to queue the
5589 alias. This saves a tad of memory. */
5590 if (cgraph_global_info_ready)
5591 target_decl = find_decl (target);
5592 else
5593 target_decl= NULL;
5594 if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5595 || cgraph_state >= CGRAPH_STATE_EXPANSION)
5596 do_assemble_alias (decl, target);
5597 else
5598 {
5599 alias_pair p = {decl, target};
5600 vec_safe_push (alias_pairs, p);
5601 }
5602 }
5603
5604 /* Record and output a table of translations from original function
5605 to its transaction aware clone. Note that tm_pure functions are
5606 considered to be their own clone. */
5607
5608 static GTY((if_marked ("tree_map_marked_p"), param_is (struct tree_map)))
5609 htab_t tm_clone_hash;
5610
5611 void
5612 record_tm_clone_pair (tree o, tree n)
5613 {
5614 struct tree_map **slot, *h;
5615
5616 if (tm_clone_hash == NULL)
5617 tm_clone_hash = htab_create_ggc (32, tree_map_hash, tree_map_eq, 0);
5618
5619 h = ggc_alloc_tree_map ();
5620 h->hash = htab_hash_pointer (o);
5621 h->base.from = o;
5622 h->to = n;
5623
5624 slot = (struct tree_map **)
5625 htab_find_slot_with_hash (tm_clone_hash, h, h->hash, INSERT);
5626 *slot = h;
5627 }
5628
5629 tree
5630 get_tm_clone_pair (tree o)
5631 {
5632 if (tm_clone_hash)
5633 {
5634 struct tree_map *h, in;
5635
5636 in.base.from = o;
5637 in.hash = htab_hash_pointer (o);
5638 h = (struct tree_map *) htab_find_with_hash (tm_clone_hash,
5639 &in, in.hash);
5640 if (h)
5641 return h->to;
5642 }
5643 return NULL_TREE;
5644 }
5645
5646 typedef struct tm_alias_pair
5647 {
5648 unsigned int uid;
5649 tree from;
5650 tree to;
5651 } tm_alias_pair;
5652
5653
5654 /* Helper function for finish_tm_clone_pairs. Dump a hash table entry
5655 into a VEC in INFO. */
5656
5657 static int
5658 dump_tm_clone_to_vec (void **slot, void *info)
5659 {
5660 struct tree_map *map = (struct tree_map *) *slot;
5661 vec<tm_alias_pair> *tm_alias_pairs = (vec<tm_alias_pair> *) info;
5662 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
5663 tm_alias_pairs->safe_push (p);
5664 return 1;
5665 }
5666
5667 /* Dump the actual pairs to the .tm_clone_table section. */
5668
5669 static void
5670 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
5671 {
5672 unsigned i;
5673 tm_alias_pair *p;
5674 bool switched = false;
5675
5676 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
5677 {
5678 tree src = p->from;
5679 tree dst = p->to;
5680 struct cgraph_node *src_n = cgraph_get_node (src);
5681 struct cgraph_node *dst_n = cgraph_get_node (dst);
5682
5683 /* The function ipa_tm_create_version() marks the clone as needed if
5684 the original function was needed. But we also mark the clone as
5685 needed if we ever called the clone indirectly through
5686 TM_GETTMCLONE. If neither of these are true, we didn't generate
5687 a clone, and we didn't call it indirectly... no sense keeping it
5688 in the clone table. */
5689 if (!dst_n || !dst_n->symbol.definition)
5690 continue;
5691
5692 /* This covers the case where we have optimized the original
5693 function away, and only access the transactional clone. */
5694 if (!src_n || !src_n->symbol.definition)
5695 continue;
5696
5697 if (!switched)
5698 {
5699 switch_to_section (targetm.asm_out.tm_clone_table_section ());
5700 assemble_align (POINTER_SIZE);
5701 switched = true;
5702 }
5703
5704 assemble_integer (XEXP (DECL_RTL (src), 0),
5705 POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
5706 assemble_integer (XEXP (DECL_RTL (dst), 0),
5707 POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
5708 }
5709 }
5710
5711 /* Provide a default for the tm_clone_table section. */
5712
5713 section *
5714 default_clone_table_section (void)
5715 {
5716 return get_named_section (NULL, ".tm_clone_table", 3);
5717 }
5718
5719 /* Helper comparison function for qsorting by the DECL_UID stored in
5720 alias_pair->emitted_diags. */
5721
5722 static int
5723 tm_alias_pair_cmp (const void *x, const void *y)
5724 {
5725 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
5726 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
5727 if (p1->uid < p2->uid)
5728 return -1;
5729 if (p1->uid > p2->uid)
5730 return 1;
5731 return 0;
5732 }
5733
5734 void
5735 finish_tm_clone_pairs (void)
5736 {
5737 vec<tm_alias_pair> tm_alias_pairs = vNULL;
5738
5739 if (tm_clone_hash == NULL)
5740 return;
5741
5742 /* We need a determenistic order for the .tm_clone_table, otherwise
5743 we will get bootstrap comparison failures, so dump the hash table
5744 to a vector, sort it, and dump the vector. */
5745
5746 /* Dump the hashtable to a vector. */
5747 htab_traverse_noresize (tm_clone_hash, dump_tm_clone_to_vec,
5748 (void *) &tm_alias_pairs);
5749 /* Sort it. */
5750 tm_alias_pairs.qsort (tm_alias_pair_cmp);
5751
5752 /* Dump it. */
5753 dump_tm_clone_pairs (tm_alias_pairs);
5754
5755 htab_delete (tm_clone_hash);
5756 tm_clone_hash = NULL;
5757 tm_alias_pairs.release ();
5758 }
5759
5760
5761 /* Emit an assembler directive to set symbol for DECL visibility to
5762 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
5763
5764 void
5765 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
5766 int vis ATTRIBUTE_UNUSED)
5767 {
5768 #ifdef HAVE_GAS_HIDDEN
5769 static const char * const visibility_types[] = {
5770 NULL, "protected", "hidden", "internal"
5771 };
5772
5773 const char *name, *type;
5774
5775 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5776 type = visibility_types[vis];
5777
5778 fprintf (asm_out_file, "\t.%s\t", type);
5779 assemble_name (asm_out_file, name);
5780 fprintf (asm_out_file, "\n");
5781 #else
5782 if (!DECL_ARTIFICIAL (decl))
5783 warning (OPT_Wattributes, "visibility attribute not supported "
5784 "in this configuration; ignored");
5785 #endif
5786 }
5787
5788 /* A helper function to call assemble_visibility when needed for a decl. */
5789
5790 int
5791 maybe_assemble_visibility (tree decl)
5792 {
5793 enum symbol_visibility vis = DECL_VISIBILITY (decl);
5794
5795 if (vis != VISIBILITY_DEFAULT)
5796 {
5797 targetm.asm_out.assemble_visibility (decl, vis);
5798 return 1;
5799 }
5800 else
5801 return 0;
5802 }
5803
5804 /* Returns 1 if the target configuration supports defining public symbols
5805 so that one of them will be chosen at link time instead of generating a
5806 multiply-defined symbol error, whether through the use of weak symbols or
5807 a target-specific mechanism for having duplicates discarded. */
5808
5809 int
5810 supports_one_only (void)
5811 {
5812 if (SUPPORTS_ONE_ONLY)
5813 return 1;
5814 return TARGET_SUPPORTS_WEAK;
5815 }
5816
5817 /* Set up DECL as a public symbol that can be defined in multiple
5818 translation units without generating a linker error. */
5819
5820 void
5821 make_decl_one_only (tree decl, tree comdat_group)
5822 {
5823 gcc_assert (TREE_CODE (decl) == VAR_DECL
5824 || TREE_CODE (decl) == FUNCTION_DECL);
5825
5826 TREE_PUBLIC (decl) = 1;
5827
5828 if (SUPPORTS_ONE_ONLY)
5829 {
5830 #ifdef MAKE_DECL_ONE_ONLY
5831 MAKE_DECL_ONE_ONLY (decl);
5832 #endif
5833 DECL_COMDAT_GROUP (decl) = comdat_group;
5834 }
5835 else if (TREE_CODE (decl) == VAR_DECL
5836 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node))
5837 DECL_COMMON (decl) = 1;
5838 else
5839 {
5840 gcc_assert (TARGET_SUPPORTS_WEAK);
5841 DECL_WEAK (decl) = 1;
5842 }
5843 }
5844
5845 void
5846 init_varasm_once (void)
5847 {
5848 section_htab = htab_create_ggc (31, section_entry_hash,
5849 section_entry_eq, NULL);
5850 object_block_htab = htab_create_ggc (31, object_block_entry_hash,
5851 object_block_entry_eq, NULL);
5852 const_desc_htab = htab_create_ggc (1009, const_desc_hash,
5853 const_desc_eq, NULL);
5854
5855 const_alias_set = new_alias_set ();
5856 shared_constant_pool = create_constant_pool ();
5857
5858 #ifdef TEXT_SECTION_ASM_OP
5859 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
5860 TEXT_SECTION_ASM_OP);
5861 #endif
5862
5863 #ifdef DATA_SECTION_ASM_OP
5864 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5865 DATA_SECTION_ASM_OP);
5866 #endif
5867
5868 #ifdef SDATA_SECTION_ASM_OP
5869 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5870 SDATA_SECTION_ASM_OP);
5871 #endif
5872
5873 #ifdef READONLY_DATA_SECTION_ASM_OP
5874 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
5875 READONLY_DATA_SECTION_ASM_OP);
5876 #endif
5877
5878 #ifdef CTORS_SECTION_ASM_OP
5879 ctors_section = get_unnamed_section (0, output_section_asm_op,
5880 CTORS_SECTION_ASM_OP);
5881 #endif
5882
5883 #ifdef DTORS_SECTION_ASM_OP
5884 dtors_section = get_unnamed_section (0, output_section_asm_op,
5885 DTORS_SECTION_ASM_OP);
5886 #endif
5887
5888 #ifdef BSS_SECTION_ASM_OP
5889 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5890 output_section_asm_op,
5891 BSS_SECTION_ASM_OP);
5892 #endif
5893
5894 #ifdef SBSS_SECTION_ASM_OP
5895 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5896 output_section_asm_op,
5897 SBSS_SECTION_ASM_OP);
5898 #endif
5899
5900 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5901 | SECTION_COMMON, emit_tls_common);
5902 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5903 | SECTION_COMMON, emit_local);
5904 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5905 | SECTION_COMMON, emit_common);
5906
5907 #if defined ASM_OUTPUT_ALIGNED_BSS
5908 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
5909 emit_bss);
5910 #endif
5911
5912 targetm.asm_out.init_sections ();
5913
5914 if (readonly_data_section == NULL)
5915 readonly_data_section = text_section;
5916
5917 #ifdef ASM_OUTPUT_EXTERNAL
5918 pending_assemble_externals_set = pointer_set_create ();
5919 #endif
5920 }
5921
5922 enum tls_model
5923 decl_default_tls_model (const_tree decl)
5924 {
5925 enum tls_model kind;
5926 bool is_local;
5927
5928 is_local = targetm.binds_local_p (decl);
5929 if (!flag_shlib)
5930 {
5931 if (is_local)
5932 kind = TLS_MODEL_LOCAL_EXEC;
5933 else
5934 kind = TLS_MODEL_INITIAL_EXEC;
5935 }
5936
5937 /* Local dynamic is inefficient when we're not combining the
5938 parts of the address. */
5939 else if (optimize && is_local)
5940 kind = TLS_MODEL_LOCAL_DYNAMIC;
5941 else
5942 kind = TLS_MODEL_GLOBAL_DYNAMIC;
5943 if (kind < flag_tls_default)
5944 kind = flag_tls_default;
5945
5946 return kind;
5947 }
5948
5949 /* Select a set of attributes for section NAME based on the properties
5950 of DECL and whether or not RELOC indicates that DECL's initializer
5951 might contain runtime relocations.
5952
5953 We make the section read-only and executable for a function decl,
5954 read-only for a const data decl, and writable for a non-const data decl. */
5955
5956 unsigned int
5957 default_section_type_flags (tree decl, const char *name, int reloc)
5958 {
5959 unsigned int flags;
5960
5961 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
5962 flags = SECTION_CODE;
5963 else if (decl)
5964 {
5965 enum section_category category
5966 = categorize_decl_for_section (decl, reloc);
5967 if (decl_readonly_section_1 (category))
5968 flags = 0;
5969 else if (category == SECCAT_DATA_REL_RO
5970 || category == SECCAT_DATA_REL_RO_LOCAL)
5971 flags = SECTION_WRITE | SECTION_RELRO;
5972 else
5973 flags = SECTION_WRITE;
5974 }
5975 else
5976 {
5977 flags = SECTION_WRITE;
5978 if (strcmp (name, ".data.rel.ro") == 0
5979 || strcmp (name, ".data.rel.ro.local") == 0)
5980 flags |= SECTION_RELRO;
5981 }
5982
5983 if (decl && DECL_P (decl) && DECL_ONE_ONLY (decl))
5984 flags |= SECTION_LINKONCE;
5985
5986 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
5987 flags |= SECTION_TLS | SECTION_WRITE;
5988
5989 if (strcmp (name, ".bss") == 0
5990 || strncmp (name, ".bss.", 5) == 0
5991 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
5992 || strcmp (name, ".sbss") == 0
5993 || strncmp (name, ".sbss.", 6) == 0
5994 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
5995 flags |= SECTION_BSS;
5996
5997 if (strcmp (name, ".tdata") == 0
5998 || strncmp (name, ".tdata.", 7) == 0
5999 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6000 flags |= SECTION_TLS;
6001
6002 if (strcmp (name, ".tbss") == 0
6003 || strncmp (name, ".tbss.", 6) == 0
6004 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6005 flags |= SECTION_TLS | SECTION_BSS;
6006
6007 /* These three sections have special ELF types. They are neither
6008 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
6009 want to print a section type (@progbits or @nobits). If someone
6010 is silly enough to emit code or TLS variables to one of these
6011 sections, then don't handle them specially. */
6012 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6013 && (strcmp (name, ".init_array") == 0
6014 || strcmp (name, ".fini_array") == 0
6015 || strcmp (name, ".preinit_array") == 0))
6016 flags |= SECTION_NOTYPE;
6017
6018 return flags;
6019 }
6020
6021 /* Return true if the target supports some form of global BSS,
6022 either through bss_noswitch_section, or by selecting a BSS
6023 section in TARGET_ASM_SELECT_SECTION. */
6024
6025 bool
6026 have_global_bss_p (void)
6027 {
6028 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6029 }
6030
6031 /* Output assembly to switch to section NAME with attribute FLAGS.
6032 Four variants for common object file formats. */
6033
6034 void
6035 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6036 unsigned int flags ATTRIBUTE_UNUSED,
6037 tree decl ATTRIBUTE_UNUSED)
6038 {
6039 /* Some object formats don't support named sections at all. The
6040 front-end should already have flagged this as an error. */
6041 gcc_unreachable ();
6042 }
6043
6044 #ifndef TLS_SECTION_ASM_FLAG
6045 #define TLS_SECTION_ASM_FLAG 'T'
6046 #endif
6047
6048 void
6049 default_elf_asm_named_section (const char *name, unsigned int flags,
6050 tree decl ATTRIBUTE_UNUSED)
6051 {
6052 char flagchars[10], *f = flagchars;
6053
6054 /* If we have already declared this section, we can use an
6055 abbreviated form to switch back to it -- unless this section is
6056 part of a COMDAT groups, in which case GAS requires the full
6057 declaration every time. */
6058 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6059 && (flags & SECTION_DECLARED))
6060 {
6061 fprintf (asm_out_file, "\t.section\t%s\n", name);
6062 return;
6063 }
6064
6065 if (!(flags & SECTION_DEBUG))
6066 *f++ = 'a';
6067 if (flags & SECTION_EXCLUDE)
6068 *f++ = 'e';
6069 if (flags & SECTION_WRITE)
6070 *f++ = 'w';
6071 if (flags & SECTION_CODE)
6072 *f++ = 'x';
6073 if (flags & SECTION_SMALL)
6074 *f++ = 's';
6075 if (flags & SECTION_MERGE)
6076 *f++ = 'M';
6077 if (flags & SECTION_STRINGS)
6078 *f++ = 'S';
6079 if (flags & SECTION_TLS)
6080 *f++ = TLS_SECTION_ASM_FLAG;
6081 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6082 *f++ = 'G';
6083 *f = '\0';
6084
6085 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6086
6087 if (!(flags & SECTION_NOTYPE))
6088 {
6089 const char *type;
6090 const char *format;
6091
6092 if (flags & SECTION_BSS)
6093 type = "nobits";
6094 else
6095 type = "progbits";
6096
6097 format = ",@%s";
6098 /* On platforms that use "@" as the assembly comment character,
6099 use "%" instead. */
6100 if (strcmp (ASM_COMMENT_START, "@") == 0)
6101 format = ",%%%s";
6102 fprintf (asm_out_file, format, type);
6103
6104 if (flags & SECTION_ENTSIZE)
6105 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6106 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6107 {
6108 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6109 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6110 else
6111 fprintf (asm_out_file, ",%s,comdat",
6112 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6113 }
6114 }
6115
6116 putc ('\n', asm_out_file);
6117 }
6118
6119 void
6120 default_coff_asm_named_section (const char *name, unsigned int flags,
6121 tree decl ATTRIBUTE_UNUSED)
6122 {
6123 char flagchars[8], *f = flagchars;
6124
6125 if (flags & SECTION_WRITE)
6126 *f++ = 'w';
6127 if (flags & SECTION_CODE)
6128 *f++ = 'x';
6129 *f = '\0';
6130
6131 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6132 }
6133
6134 void
6135 default_pe_asm_named_section (const char *name, unsigned int flags,
6136 tree decl)
6137 {
6138 default_coff_asm_named_section (name, flags, decl);
6139
6140 if (flags & SECTION_LINKONCE)
6141 {
6142 /* Functions may have been compiled at various levels of
6143 optimization so we can't use `same_size' here.
6144 Instead, have the linker pick one. */
6145 fprintf (asm_out_file, "\t.linkonce %s\n",
6146 (flags & SECTION_CODE ? "discard" : "same_size"));
6147 }
6148 }
6149 \f
6150 /* The lame default section selector. */
6151
6152 section *
6153 default_select_section (tree decl, int reloc,
6154 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6155 {
6156 if (DECL_P (decl))
6157 {
6158 if (decl_readonly_section (decl, reloc))
6159 return readonly_data_section;
6160 }
6161 else if (TREE_CODE (decl) == CONSTRUCTOR)
6162 {
6163 if (! ((flag_pic && reloc)
6164 || !TREE_READONLY (decl)
6165 || TREE_SIDE_EFFECTS (decl)
6166 || !TREE_CONSTANT (decl)))
6167 return readonly_data_section;
6168 }
6169 else if (TREE_CODE (decl) == STRING_CST)
6170 return readonly_data_section;
6171 else if (! (flag_pic && reloc))
6172 return readonly_data_section;
6173
6174 return data_section;
6175 }
6176
6177 enum section_category
6178 categorize_decl_for_section (const_tree decl, int reloc)
6179 {
6180 enum section_category ret;
6181
6182 if (TREE_CODE (decl) == FUNCTION_DECL)
6183 return SECCAT_TEXT;
6184 else if (TREE_CODE (decl) == STRING_CST)
6185 {
6186 if (flag_mudflap
6187 || (flag_asan && asan_protect_global (CONST_CAST_TREE (decl))))
6188 /* or !flag_merge_constants */
6189 return SECCAT_RODATA;
6190 else
6191 return SECCAT_RODATA_MERGE_STR;
6192 }
6193 else if (TREE_CODE (decl) == VAR_DECL)
6194 {
6195 if (bss_initializer_p (decl))
6196 ret = SECCAT_BSS;
6197 else if (! TREE_READONLY (decl)
6198 || TREE_SIDE_EFFECTS (decl)
6199 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
6200 {
6201 /* Here the reloc_rw_mask is not testing whether the section should
6202 be read-only or not, but whether the dynamic link will have to
6203 do something. If so, we wish to segregate the data in order to
6204 minimize cache misses inside the dynamic linker. */
6205 if (reloc & targetm.asm_out.reloc_rw_mask ())
6206 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6207 else
6208 ret = SECCAT_DATA;
6209 }
6210 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6211 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6212 else if (reloc || flag_merge_constants < 2 || flag_mudflap
6213 || (flag_asan && asan_protect_global (CONST_CAST_TREE (decl))))
6214 /* C and C++ don't allow different variables to share the same
6215 location. -fmerge-all-constants allows even that (at the
6216 expense of not conforming). */
6217 ret = SECCAT_RODATA;
6218 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6219 ret = SECCAT_RODATA_MERGE_STR_INIT;
6220 else
6221 ret = SECCAT_RODATA_MERGE_CONST;
6222 }
6223 else if (TREE_CODE (decl) == CONSTRUCTOR)
6224 {
6225 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6226 || TREE_SIDE_EFFECTS (decl)
6227 || ! TREE_CONSTANT (decl))
6228 ret = SECCAT_DATA;
6229 else
6230 ret = SECCAT_RODATA;
6231 }
6232 else
6233 ret = SECCAT_RODATA;
6234
6235 /* There are no read-only thread-local sections. */
6236 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6237 {
6238 /* Note that this would be *just* SECCAT_BSS, except that there's
6239 no concept of a read-only thread-local-data section. */
6240 if (ret == SECCAT_BSS
6241 || (flag_zero_initialized_in_bss
6242 && initializer_zerop (DECL_INITIAL (decl))))
6243 ret = SECCAT_TBSS;
6244 else
6245 ret = SECCAT_TDATA;
6246 }
6247
6248 /* If the target uses small data sections, select it. */
6249 else if (targetm.in_small_data_p (decl))
6250 {
6251 if (ret == SECCAT_BSS)
6252 ret = SECCAT_SBSS;
6253 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6254 ret = SECCAT_SRODATA;
6255 else
6256 ret = SECCAT_SDATA;
6257 }
6258
6259 return ret;
6260 }
6261
6262 static bool
6263 decl_readonly_section_1 (enum section_category category)
6264 {
6265 switch (category)
6266 {
6267 case SECCAT_RODATA:
6268 case SECCAT_RODATA_MERGE_STR:
6269 case SECCAT_RODATA_MERGE_STR_INIT:
6270 case SECCAT_RODATA_MERGE_CONST:
6271 case SECCAT_SRODATA:
6272 return true;
6273 default:
6274 return false;
6275 }
6276 }
6277
6278 bool
6279 decl_readonly_section (const_tree decl, int reloc)
6280 {
6281 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6282 }
6283
6284 /* Select a section based on the above categorization. */
6285
6286 section *
6287 default_elf_select_section (tree decl, int reloc,
6288 unsigned HOST_WIDE_INT align)
6289 {
6290 const char *sname;
6291 switch (categorize_decl_for_section (decl, reloc))
6292 {
6293 case SECCAT_TEXT:
6294 /* We're not supposed to be called on FUNCTION_DECLs. */
6295 gcc_unreachable ();
6296 case SECCAT_RODATA:
6297 return readonly_data_section;
6298 case SECCAT_RODATA_MERGE_STR:
6299 return mergeable_string_section (decl, align, 0);
6300 case SECCAT_RODATA_MERGE_STR_INIT:
6301 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6302 case SECCAT_RODATA_MERGE_CONST:
6303 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6304 case SECCAT_SRODATA:
6305 sname = ".sdata2";
6306 break;
6307 case SECCAT_DATA:
6308 return data_section;
6309 case SECCAT_DATA_REL:
6310 sname = ".data.rel";
6311 break;
6312 case SECCAT_DATA_REL_LOCAL:
6313 sname = ".data.rel.local";
6314 break;
6315 case SECCAT_DATA_REL_RO:
6316 sname = ".data.rel.ro";
6317 break;
6318 case SECCAT_DATA_REL_RO_LOCAL:
6319 sname = ".data.rel.ro.local";
6320 break;
6321 case SECCAT_SDATA:
6322 sname = ".sdata";
6323 break;
6324 case SECCAT_TDATA:
6325 sname = ".tdata";
6326 break;
6327 case SECCAT_BSS:
6328 if (bss_section)
6329 return bss_section;
6330 sname = ".bss";
6331 break;
6332 case SECCAT_SBSS:
6333 sname = ".sbss";
6334 break;
6335 case SECCAT_TBSS:
6336 sname = ".tbss";
6337 break;
6338 default:
6339 gcc_unreachable ();
6340 }
6341
6342 return get_named_section (decl, sname, reloc);
6343 }
6344
6345 /* Construct a unique section name based on the decl name and the
6346 categorization performed above. */
6347
6348 void
6349 default_unique_section (tree decl, int reloc)
6350 {
6351 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6352 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6353 const char *prefix, *name, *linkonce;
6354 char *string;
6355
6356 switch (categorize_decl_for_section (decl, reloc))
6357 {
6358 case SECCAT_TEXT:
6359 prefix = one_only ? ".t" : ".text";
6360 break;
6361 case SECCAT_RODATA:
6362 case SECCAT_RODATA_MERGE_STR:
6363 case SECCAT_RODATA_MERGE_STR_INIT:
6364 case SECCAT_RODATA_MERGE_CONST:
6365 prefix = one_only ? ".r" : ".rodata";
6366 break;
6367 case SECCAT_SRODATA:
6368 prefix = one_only ? ".s2" : ".sdata2";
6369 break;
6370 case SECCAT_DATA:
6371 prefix = one_only ? ".d" : ".data";
6372 break;
6373 case SECCAT_DATA_REL:
6374 prefix = one_only ? ".d.rel" : ".data.rel";
6375 break;
6376 case SECCAT_DATA_REL_LOCAL:
6377 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6378 break;
6379 case SECCAT_DATA_REL_RO:
6380 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6381 break;
6382 case SECCAT_DATA_REL_RO_LOCAL:
6383 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6384 break;
6385 case SECCAT_SDATA:
6386 prefix = one_only ? ".s" : ".sdata";
6387 break;
6388 case SECCAT_BSS:
6389 prefix = one_only ? ".b" : ".bss";
6390 break;
6391 case SECCAT_SBSS:
6392 prefix = one_only ? ".sb" : ".sbss";
6393 break;
6394 case SECCAT_TDATA:
6395 prefix = one_only ? ".td" : ".tdata";
6396 break;
6397 case SECCAT_TBSS:
6398 prefix = one_only ? ".tb" : ".tbss";
6399 break;
6400 default:
6401 gcc_unreachable ();
6402 }
6403
6404 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
6405 name = targetm.strip_name_encoding (name);
6406
6407 /* If we're using one_only, then there needs to be a .gnu.linkonce
6408 prefix to the section name. */
6409 linkonce = one_only ? ".gnu.linkonce" : "";
6410
6411 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6412
6413 DECL_SECTION_NAME (decl) = build_string (strlen (string), string);
6414 }
6415
6416 /* Like compute_reloc_for_constant, except for an RTX. The return value
6417 is a mask for which bit 1 indicates a global relocation, and bit 0
6418 indicates a local relocation. */
6419
6420 static int
6421 compute_reloc_for_rtx_1 (rtx *xp, void *data)
6422 {
6423 int *preloc = (int *) data;
6424 rtx x = *xp;
6425
6426 switch (GET_CODE (x))
6427 {
6428 case SYMBOL_REF:
6429 *preloc |= SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6430 break;
6431 case LABEL_REF:
6432 *preloc |= 1;
6433 break;
6434 default:
6435 break;
6436 }
6437
6438 return 0;
6439 }
6440
6441 static int
6442 compute_reloc_for_rtx (rtx x)
6443 {
6444 int reloc;
6445
6446 switch (GET_CODE (x))
6447 {
6448 case CONST:
6449 case SYMBOL_REF:
6450 case LABEL_REF:
6451 reloc = 0;
6452 for_each_rtx (&x, compute_reloc_for_rtx_1, &reloc);
6453 return reloc;
6454
6455 default:
6456 return 0;
6457 }
6458 }
6459
6460 section *
6461 default_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
6462 rtx x,
6463 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6464 {
6465 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6466 return data_section;
6467 else
6468 return readonly_data_section;
6469 }
6470
6471 section *
6472 default_elf_select_rtx_section (enum machine_mode mode, rtx x,
6473 unsigned HOST_WIDE_INT align)
6474 {
6475 int reloc = compute_reloc_for_rtx (x);
6476
6477 /* ??? Handle small data here somehow. */
6478
6479 if (reloc & targetm.asm_out.reloc_rw_mask ())
6480 {
6481 if (reloc == 1)
6482 return get_named_section (NULL, ".data.rel.ro.local", 1);
6483 else
6484 return get_named_section (NULL, ".data.rel.ro", 3);
6485 }
6486
6487 return mergeable_constant_section (mode, align, 0);
6488 }
6489
6490 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6491
6492 void
6493 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6494 {
6495 rtx symbol;
6496 int flags;
6497
6498 /* Careful not to prod global register variables. */
6499 if (!MEM_P (rtl))
6500 return;
6501 symbol = XEXP (rtl, 0);
6502 if (GET_CODE (symbol) != SYMBOL_REF)
6503 return;
6504
6505 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6506 if (TREE_CODE (decl) == FUNCTION_DECL)
6507 flags |= SYMBOL_FLAG_FUNCTION;
6508 if (targetm.binds_local_p (decl))
6509 flags |= SYMBOL_FLAG_LOCAL;
6510 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6511 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6512 else if (targetm.in_small_data_p (decl))
6513 flags |= SYMBOL_FLAG_SMALL;
6514 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6515 being PUBLIC, the thing *must* be defined in this translation unit.
6516 Prevent this buglet from being propagated into rtl code as well. */
6517 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6518 flags |= SYMBOL_FLAG_EXTERNAL;
6519
6520 SYMBOL_REF_FLAGS (symbol) = flags;
6521 }
6522
6523 /* By default, we do nothing for encode_section_info, so we need not
6524 do anything but discard the '*' marker. */
6525
6526 const char *
6527 default_strip_name_encoding (const char *str)
6528 {
6529 return str + (*str == '*');
6530 }
6531
6532 #ifdef ASM_OUTPUT_DEF
6533 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6534 anchor relative to ".", the current section position. */
6535
6536 void
6537 default_asm_output_anchor (rtx symbol)
6538 {
6539 char buffer[100];
6540
6541 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6542 SYMBOL_REF_BLOCK_OFFSET (symbol));
6543 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6544 }
6545 #endif
6546
6547 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6548
6549 bool
6550 default_use_anchors_for_symbol_p (const_rtx symbol)
6551 {
6552 section *sect;
6553 tree decl;
6554
6555 /* Don't use anchors for mergeable sections. The linker might move
6556 the objects around. */
6557 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6558 if (sect->common.flags & SECTION_MERGE)
6559 return false;
6560
6561 /* Don't use anchors for small data sections. The small data register
6562 acts as an anchor for such sections. */
6563 if (sect->common.flags & SECTION_SMALL)
6564 return false;
6565
6566 decl = SYMBOL_REF_DECL (symbol);
6567 if (decl && DECL_P (decl))
6568 {
6569 /* Don't use section anchors for decls that might be defined or
6570 usurped by other modules. */
6571 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6572 return false;
6573
6574 /* Don't use section anchors for decls that will be placed in a
6575 small data section. */
6576 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6577 one above. The problem is that we only use SECTION_SMALL for
6578 sections that should be marked as small in the section directive. */
6579 if (targetm.in_small_data_p (decl))
6580 return false;
6581 }
6582 return true;
6583 }
6584
6585 /* Return true when RESOLUTION indicate that symbol will be bound to the
6586 definition provided by current .o file. */
6587
6588 static bool
6589 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
6590 {
6591 return (resolution == LDPR_PREVAILING_DEF
6592 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6593 || resolution == LDPR_PREVAILING_DEF_IRONLY);
6594 }
6595
6596 /* Return true when RESOLUTION indicate that symbol will be bound locally
6597 within current executable or DSO. */
6598
6599 static bool
6600 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
6601 {
6602 return (resolution == LDPR_PREVAILING_DEF
6603 || resolution == LDPR_PREVAILING_DEF_IRONLY
6604 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6605 || resolution == LDPR_PREEMPTED_REG
6606 || resolution == LDPR_PREEMPTED_IR
6607 || resolution == LDPR_RESOLVED_IR
6608 || resolution == LDPR_RESOLVED_EXEC);
6609 }
6610
6611 /* Assume ELF-ish defaults, since that's pretty much the most liberal
6612 wrt cross-module name binding. */
6613
6614 bool
6615 default_binds_local_p (const_tree exp)
6616 {
6617 return default_binds_local_p_1 (exp, flag_shlib);
6618 }
6619
6620 bool
6621 default_binds_local_p_1 (const_tree exp, int shlib)
6622 {
6623 bool local_p;
6624 bool resolved_locally = false;
6625 bool resolved_to_local_def = false;
6626
6627 /* With resolution file in hands, take look into resolutions.
6628 We can't just return true for resolved_locally symbols,
6629 because dynamic linking might overwrite symbols
6630 in shared libraries. */
6631 if (TREE_CODE (exp) == VAR_DECL && TREE_PUBLIC (exp)
6632 && (TREE_STATIC (exp) || DECL_EXTERNAL (exp)))
6633 {
6634 struct varpool_node *vnode = varpool_get_node (exp);
6635 if (vnode && resolution_local_p (vnode->symbol.resolution))
6636 resolved_locally = true;
6637 if (vnode
6638 && resolution_to_local_definition_p (vnode->symbol.resolution))
6639 resolved_to_local_def = true;
6640 }
6641 else if (TREE_CODE (exp) == FUNCTION_DECL && TREE_PUBLIC (exp))
6642 {
6643 struct cgraph_node *node = cgraph_get_node (exp);
6644 if (node
6645 && resolution_local_p (node->symbol.resolution))
6646 resolved_locally = true;
6647 if (node
6648 && resolution_to_local_definition_p (node->symbol.resolution))
6649 resolved_to_local_def = true;
6650 }
6651
6652 /* A non-decl is an entry in the constant pool. */
6653 if (!DECL_P (exp))
6654 local_p = true;
6655 /* Weakrefs may not bind locally, even though the weakref itself is always
6656 static and therefore local. Similarly, the resolver for ifunc functions
6657 might resolve to a non-local function.
6658 FIXME: We can resolve the weakref case more curefuly by looking at the
6659 weakref alias. */
6660 else if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
6661 || (TREE_CODE (exp) == FUNCTION_DECL
6662 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
6663 local_p = false;
6664 /* Static variables are always local. */
6665 else if (! TREE_PUBLIC (exp))
6666 local_p = true;
6667 /* A variable is local if the user has said explicitly that it will
6668 be. */
6669 else if ((DECL_VISIBILITY_SPECIFIED (exp)
6670 || resolved_to_local_def)
6671 && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6672 local_p = true;
6673 /* Variables defined outside this object might not be local. */
6674 else if (DECL_EXTERNAL (exp) && !resolved_locally)
6675 local_p = false;
6676 /* If defined in this object and visibility is not default, must be
6677 local. */
6678 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6679 local_p = true;
6680 /* Default visibility weak data can be overridden by a strong symbol
6681 in another module and so are not local. */
6682 else if (DECL_WEAK (exp)
6683 && !resolved_locally)
6684 local_p = false;
6685 /* If PIC, then assume that any global name can be overridden by
6686 symbols resolved from other modules. */
6687 else if (shlib)
6688 local_p = false;
6689 /* Uninitialized COMMON variable may be unified with symbols
6690 resolved from other modules. */
6691 else if (DECL_COMMON (exp)
6692 && !resolved_locally
6693 && (DECL_INITIAL (exp) == NULL
6694 || DECL_INITIAL (exp) == error_mark_node))
6695 local_p = false;
6696 /* Otherwise we're left with initialized (or non-common) global data
6697 which is of necessity defined locally. */
6698 else
6699 local_p = true;
6700
6701 return local_p;
6702 }
6703
6704 /* Return true when references to DECL must bind to current definition in
6705 final executable.
6706
6707 The condition is usually equivalent to whether the function binds to the
6708 current module (shared library or executable), that is to binds_local_p.
6709 We use this fact to avoid need for another target hook and implement
6710 the logic using binds_local_p and just special cases where
6711 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
6712 the weak definitions (that can be overwritten at linktime by other
6713 definition from different object file) and when resolution info is available
6714 we simply use the knowledge passed to us by linker plugin. */
6715 bool
6716 decl_binds_to_current_def_p (tree decl)
6717 {
6718 gcc_assert (DECL_P (decl));
6719 if (!TREE_PUBLIC (decl))
6720 return true;
6721 if (!targetm.binds_local_p (decl))
6722 return false;
6723 /* When resolution is available, just use it. */
6724 if (TREE_CODE (decl) == VAR_DECL
6725 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl)))
6726 {
6727 struct varpool_node *vnode = varpool_get_node (decl);
6728 if (vnode
6729 && vnode->symbol.resolution != LDPR_UNKNOWN)
6730 return resolution_to_local_definition_p (vnode->symbol.resolution);
6731 }
6732 else if (TREE_CODE (decl) == FUNCTION_DECL)
6733 {
6734 struct cgraph_node *node = cgraph_get_node (decl);
6735 if (node
6736 && node->symbol.resolution != LDPR_UNKNOWN)
6737 return resolution_to_local_definition_p (node->symbol.resolution);
6738 }
6739 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
6740 binds locally but still can be overwritten).
6741 This rely on fact that binds_local_p behave as decl_replaceable_p
6742 for all other declaration types. */
6743 return !DECL_WEAK (decl);
6744 }
6745
6746 /* A replaceable function or variable is one which may be replaced
6747 at link-time with an entirely different definition, provided that the
6748 replacement has the same type. For example, functions declared
6749 with __attribute__((weak)) on most systems are replaceable.
6750
6751 COMDAT functions are not replaceable, since all definitions of the
6752 function must be equivalent. It is important that COMDAT functions
6753 not be treated as replaceable so that use of C++ template
6754 instantiations is not penalized. */
6755
6756 bool
6757 decl_replaceable_p (tree decl)
6758 {
6759 gcc_assert (DECL_P (decl));
6760 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
6761 return false;
6762 return !decl_binds_to_current_def_p (decl);
6763 }
6764
6765 /* Default function to output code that will globalize a label. A
6766 target must define GLOBAL_ASM_OP or provide its own function to
6767 globalize a label. */
6768 #ifdef GLOBAL_ASM_OP
6769 void
6770 default_globalize_label (FILE * stream, const char *name)
6771 {
6772 fputs (GLOBAL_ASM_OP, stream);
6773 assemble_name (stream, name);
6774 putc ('\n', stream);
6775 }
6776 #endif /* GLOBAL_ASM_OP */
6777
6778 /* Default function to output code that will globalize a declaration. */
6779 void
6780 default_globalize_decl_name (FILE * stream, tree decl)
6781 {
6782 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
6783 targetm.asm_out.globalize_label (stream, name);
6784 }
6785
6786 /* Default function to output a label for unwind information. The
6787 default is to do nothing. A target that needs nonlocal labels for
6788 unwind information must provide its own function to do this. */
6789 void
6790 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
6791 tree decl ATTRIBUTE_UNUSED,
6792 int for_eh ATTRIBUTE_UNUSED,
6793 int empty ATTRIBUTE_UNUSED)
6794 {
6795 }
6796
6797 /* Default function to output a label to divide up the exception table.
6798 The default is to do nothing. A target that needs/wants to divide
6799 up the table must provide it's own function to do this. */
6800 void
6801 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
6802 {
6803 }
6804
6805 /* This is how to output an internal numbered label where PREFIX is
6806 the class of label and LABELNO is the number within the class. */
6807
6808 void
6809 default_generate_internal_label (char *buf, const char *prefix,
6810 unsigned long labelno)
6811 {
6812 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6813 }
6814
6815 /* This is how to output an internal numbered label where PREFIX is
6816 the class of label and LABELNO is the number within the class. */
6817
6818 void
6819 default_internal_label (FILE *stream, const char *prefix,
6820 unsigned long labelno)
6821 {
6822 char *const buf = (char *) alloca (40 + strlen (prefix));
6823 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6824 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
6825 }
6826
6827
6828 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
6829
6830 void
6831 default_asm_declare_constant_name (FILE *file, const char *name,
6832 const_tree exp ATTRIBUTE_UNUSED,
6833 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
6834 {
6835 assemble_label (file, name);
6836 }
6837
6838 /* This is the default behavior at the beginning of a file. It's
6839 controlled by two other target-hook toggles. */
6840 void
6841 default_file_start (void)
6842 {
6843 if (targetm.asm_file_start_app_off
6844 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
6845 fputs (ASM_APP_OFF, asm_out_file);
6846
6847 if (targetm.asm_file_start_file_directive)
6848 output_file_directive (asm_out_file, main_input_filename);
6849 }
6850
6851 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
6852 which emits a special section directive used to indicate whether or
6853 not this object file needs an executable stack. This is primarily
6854 a GNU extension to ELF but could be used on other targets. */
6855
6856 int trampolines_created;
6857
6858 void
6859 file_end_indicate_exec_stack (void)
6860 {
6861 unsigned int flags = SECTION_DEBUG;
6862 if (trampolines_created)
6863 flags |= SECTION_CODE;
6864
6865 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
6866 }
6867
6868 /* Emit a special section directive to indicate that this object file
6869 was compiled with -fsplit-stack. This is used to let the linker
6870 detect calls between split-stack code and non-split-stack code, so
6871 that it can modify the split-stack code to allocate a sufficiently
6872 large stack. We emit another special section if there are any
6873 functions in this file which have the no_split_stack attribute, to
6874 prevent the linker from warning about being unable to convert the
6875 functions if they call non-split-stack code. */
6876
6877 void
6878 file_end_indicate_split_stack (void)
6879 {
6880 if (flag_split_stack)
6881 {
6882 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
6883 NULL));
6884 if (saw_no_split_stack)
6885 switch_to_section (get_section (".note.GNU-no-split-stack",
6886 SECTION_DEBUG, NULL));
6887 }
6888 }
6889
6890 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
6891 a get_unnamed_section callback. */
6892
6893 void
6894 output_section_asm_op (const void *directive)
6895 {
6896 fprintf (asm_out_file, "%s\n", (const char *) directive);
6897 }
6898
6899 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
6900 the current section is NEW_SECTION. */
6901
6902 void
6903 switch_to_section (section *new_section)
6904 {
6905 if (in_section == new_section)
6906 return;
6907
6908 if (new_section->common.flags & SECTION_FORGET)
6909 in_section = NULL;
6910 else
6911 in_section = new_section;
6912
6913 switch (SECTION_STYLE (new_section))
6914 {
6915 case SECTION_NAMED:
6916 targetm.asm_out.named_section (new_section->named.name,
6917 new_section->named.common.flags,
6918 new_section->named.decl);
6919 break;
6920
6921 case SECTION_UNNAMED:
6922 new_section->unnamed.callback (new_section->unnamed.data);
6923 break;
6924
6925 case SECTION_NOSWITCH:
6926 gcc_unreachable ();
6927 break;
6928 }
6929
6930 new_section->common.flags |= SECTION_DECLARED;
6931 }
6932
6933 /* If block symbol SYMBOL has not yet been assigned an offset, place
6934 it at the end of its block. */
6935
6936 void
6937 place_block_symbol (rtx symbol)
6938 {
6939 unsigned HOST_WIDE_INT size, mask, offset;
6940 struct constant_descriptor_rtx *desc;
6941 unsigned int alignment;
6942 struct object_block *block;
6943 tree decl;
6944
6945 gcc_assert (SYMBOL_REF_BLOCK (symbol));
6946 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
6947 return;
6948
6949 /* Work out the symbol's size and alignment. */
6950 if (CONSTANT_POOL_ADDRESS_P (symbol))
6951 {
6952 desc = SYMBOL_REF_CONSTANT (symbol);
6953 alignment = desc->align;
6954 size = GET_MODE_SIZE (desc->mode);
6955 }
6956 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
6957 {
6958 decl = SYMBOL_REF_DECL (symbol);
6959 alignment = DECL_ALIGN (decl);
6960 size = get_constant_size (DECL_INITIAL (decl));
6961 if (flag_asan
6962 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
6963 && asan_protect_global (DECL_INITIAL (decl)))
6964 size += asan_red_zone_size (size);
6965 }
6966 else
6967 {
6968 decl = SYMBOL_REF_DECL (symbol);
6969 alignment = DECL_ALIGN (decl);
6970 size = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
6971 if (flag_asan && asan_protect_global (decl))
6972 {
6973 size += asan_red_zone_size (size);
6974 alignment = MAX (alignment,
6975 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
6976 }
6977 }
6978
6979 /* Calculate the object's offset from the start of the block. */
6980 block = SYMBOL_REF_BLOCK (symbol);
6981 mask = alignment / BITS_PER_UNIT - 1;
6982 offset = (block->size + mask) & ~mask;
6983 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
6984
6985 /* Record the block's new alignment and size. */
6986 block->alignment = MAX (block->alignment, alignment);
6987 block->size = offset + size;
6988
6989 vec_safe_push (block->objects, symbol);
6990 }
6991
6992 /* Return the anchor that should be used to address byte offset OFFSET
6993 from the first object in BLOCK. MODEL is the TLS model used
6994 to access it. */
6995
6996 rtx
6997 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
6998 enum tls_model model)
6999 {
7000 char label[100];
7001 unsigned int begin, middle, end;
7002 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7003 rtx anchor;
7004
7005 /* Work out the anchor's offset. Use an offset of 0 for the first
7006 anchor so that we don't pessimize the case where we take the address
7007 of a variable at the beginning of the block. This is particularly
7008 useful when a block has only one variable assigned to it.
7009
7010 We try to place anchors RANGE bytes apart, so there can then be
7011 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7012 a ptr_mode offset. With some target settings, the lowest such
7013 anchor might be out of range for the lowest ptr_mode offset;
7014 likewise the highest anchor for the highest offset. Use anchors
7015 at the extreme ends of the ptr_mode range in such cases.
7016
7017 All arithmetic uses unsigned integers in order to avoid
7018 signed overflow. */
7019 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7020 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7021 range = max_offset - min_offset + 1;
7022 if (range == 0)
7023 offset = 0;
7024 else
7025 {
7026 bias = 1 << (GET_MODE_BITSIZE (ptr_mode) - 1);
7027 if (offset < 0)
7028 {
7029 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7030 delta -= delta % range;
7031 if (delta > bias)
7032 delta = bias;
7033 offset = (HOST_WIDE_INT) (-delta);
7034 }
7035 else
7036 {
7037 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7038 delta -= delta % range;
7039 if (delta > bias - 1)
7040 delta = bias - 1;
7041 offset = (HOST_WIDE_INT) delta;
7042 }
7043 }
7044
7045 /* Do a binary search to see if there's already an anchor we can use.
7046 Set BEGIN to the new anchor's index if not. */
7047 begin = 0;
7048 end = vec_safe_length (block->anchors);
7049 while (begin != end)
7050 {
7051 middle = (end + begin) / 2;
7052 anchor = (*block->anchors)[middle];
7053 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7054 end = middle;
7055 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7056 begin = middle + 1;
7057 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7058 end = middle;
7059 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7060 begin = middle + 1;
7061 else
7062 return anchor;
7063 }
7064
7065 /* Create a new anchor with a unique label. */
7066 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7067 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7068 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7069 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7070
7071 /* Insert it at index BEGIN. */
7072 vec_safe_insert (block->anchors, begin, anchor);
7073 return anchor;
7074 }
7075
7076 /* Output the objects in BLOCK. */
7077
7078 static void
7079 output_object_block (struct object_block *block)
7080 {
7081 struct constant_descriptor_rtx *desc;
7082 unsigned int i;
7083 HOST_WIDE_INT offset;
7084 tree decl;
7085 rtx symbol;
7086
7087 if (!block->objects)
7088 return;
7089
7090 /* Switch to the section and make sure that the first byte is
7091 suitably aligned. */
7092 switch_to_section (block->sect);
7093 assemble_align (block->alignment);
7094
7095 /* Define the values of all anchors relative to the current section
7096 position. */
7097 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7098 targetm.asm_out.output_anchor (symbol);
7099
7100 /* Output the objects themselves. */
7101 offset = 0;
7102 FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7103 {
7104 /* Move to the object's offset, padding with zeros if necessary. */
7105 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7106 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7107 if (CONSTANT_POOL_ADDRESS_P (symbol))
7108 {
7109 desc = SYMBOL_REF_CONSTANT (symbol);
7110 output_constant_pool_1 (desc, 1);
7111 offset += GET_MODE_SIZE (desc->mode);
7112 }
7113 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7114 {
7115 HOST_WIDE_INT size;
7116 decl = SYMBOL_REF_DECL (symbol);
7117 assemble_constant_contents (DECL_INITIAL (decl), XSTR (symbol, 0),
7118 DECL_ALIGN (decl));
7119 size = get_constant_size (DECL_INITIAL (decl));
7120 offset += size;
7121 if (flag_asan
7122 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7123 && asan_protect_global (DECL_INITIAL (decl)))
7124 {
7125 size = asan_red_zone_size (size);
7126 assemble_zeros (size);
7127 offset += size;
7128 }
7129 }
7130 else
7131 {
7132 HOST_WIDE_INT size;
7133 decl = SYMBOL_REF_DECL (symbol);
7134 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7135 size = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
7136 offset += size;
7137 if (flag_asan && asan_protect_global (decl))
7138 {
7139 size = asan_red_zone_size (size);
7140 assemble_zeros (size);
7141 offset += size;
7142 }
7143 }
7144 }
7145 }
7146
7147 /* A htab_traverse callback used to call output_object_block for
7148 each member of object_block_htab. */
7149
7150 static int
7151 output_object_block_htab (void **slot, void *data ATTRIBUTE_UNUSED)
7152 {
7153 output_object_block ((struct object_block *) (*slot));
7154 return 1;
7155 }
7156
7157 /* Output the definitions of all object_blocks. */
7158
7159 void
7160 output_object_blocks (void)
7161 {
7162 htab_traverse (object_block_htab, output_object_block_htab, NULL);
7163 }
7164
7165 /* This function provides a possible implementation of the
7166 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7167 by -frecord-gcc-switches it creates a new mergeable, string section in the
7168 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7169 contains the switches in ASCII format.
7170
7171 FIXME: This code does not correctly handle double quote characters
7172 that appear inside strings, (it strips them rather than preserving them).
7173 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7174 characters - instead it treats them as sub-string separators. Since
7175 we want to emit NUL strings terminators into the object file we have to use
7176 ASM_OUTPUT_SKIP. */
7177
7178 int
7179 elf_record_gcc_switches (print_switch_type type, const char * name)
7180 {
7181 switch (type)
7182 {
7183 case SWITCH_TYPE_PASSED:
7184 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7185 ASM_OUTPUT_SKIP (asm_out_file, (unsigned HOST_WIDE_INT) 1);
7186 break;
7187
7188 case SWITCH_TYPE_DESCRIPTIVE:
7189 if (name == NULL)
7190 {
7191 /* Distinguish between invocations where name is NULL. */
7192 static bool started = false;
7193
7194 if (!started)
7195 {
7196 section * sec;
7197
7198 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7199 SECTION_DEBUG
7200 | SECTION_MERGE
7201 | SECTION_STRINGS
7202 | (SECTION_ENTSIZE & 1),
7203 NULL);
7204 switch_to_section (sec);
7205 started = true;
7206 }
7207 }
7208
7209 default:
7210 break;
7211 }
7212
7213 /* The return value is currently ignored by the caller, but must be 0.
7214 For -fverbose-asm the return value would be the number of characters
7215 emitted into the assembler file. */
7216 return 0;
7217 }
7218
7219 /* Emit text to declare externally defined symbols. It is needed to
7220 properly support non-default visibility. */
7221 void
7222 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7223 tree decl,
7224 const char *name ATTRIBUTE_UNUSED)
7225 {
7226 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7227 set in order to avoid putting out names that are never really
7228 used. */
7229 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7230 && targetm.binds_local_p (decl))
7231 maybe_assemble_visibility (decl);
7232 }
7233
7234 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7235
7236 void
7237 default_asm_output_source_filename (FILE *file, const char *name)
7238 {
7239 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7240 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7241 #else
7242 fprintf (file, "\t.file\t");
7243 output_quoted_string (file, name);
7244 putc ('\n', file);
7245 #endif
7246 }
7247
7248 /* Output a file name in the form wanted by System V. */
7249
7250 void
7251 output_file_directive (FILE *asm_file, const char *input_name)
7252 {
7253 int len;
7254 const char *na;
7255
7256 if (input_name == NULL)
7257 input_name = "<stdin>";
7258 else
7259 input_name = remap_debug_filename (input_name);
7260
7261 len = strlen (input_name);
7262 na = input_name + len;
7263
7264 /* NA gets INPUT_NAME sans directory names. */
7265 while (na > input_name)
7266 {
7267 if (IS_DIR_SEPARATOR (na[-1]))
7268 break;
7269 na--;
7270 }
7271
7272 targetm.asm_out.output_source_filename (asm_file, na);
7273 }
7274
7275 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7276 EXP. */
7277 rtx
7278 make_debug_expr_from_rtl (const_rtx exp)
7279 {
7280 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7281 enum machine_mode mode = GET_MODE (exp);
7282 rtx dval;
7283
7284 DECL_ARTIFICIAL (ddecl) = 1;
7285 if (REG_P (exp) && REG_EXPR (exp))
7286 type = TREE_TYPE (REG_EXPR (exp));
7287 else if (MEM_P (exp) && MEM_EXPR (exp))
7288 type = TREE_TYPE (MEM_EXPR (exp));
7289 else
7290 type = NULL_TREE;
7291 if (type && TYPE_MODE (type) == mode)
7292 TREE_TYPE (ddecl) = type;
7293 else
7294 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7295 DECL_MODE (ddecl) = mode;
7296 dval = gen_rtx_DEBUG_EXPR (mode);
7297 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7298 SET_DECL_RTL (ddecl, dval);
7299 return dval;
7300 }
7301
7302 #ifdef ELF_ASCII_ESCAPES
7303 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7304
7305 void
7306 default_elf_asm_output_limited_string (FILE *f, const char *s)
7307 {
7308 int escape;
7309 unsigned char c;
7310
7311 fputs (STRING_ASM_OP, f);
7312 putc ('"', f);
7313 while (*s != '\0')
7314 {
7315 c = *s;
7316 escape = ELF_ASCII_ESCAPES[c];
7317 switch (escape)
7318 {
7319 case 0:
7320 putc (c, f);
7321 break;
7322 case 1:
7323 /* TODO: Print in hex with fast function, important for -flto. */
7324 fprintf (f, "\\%03o", c);
7325 break;
7326 default:
7327 putc ('\\', f);
7328 putc (escape, f);
7329 break;
7330 }
7331 s++;
7332 }
7333 putc ('\"', f);
7334 putc ('\n', f);
7335 }
7336
7337 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7338
7339 void
7340 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7341 {
7342 const char *limit = s + len;
7343 const char *last_null = NULL;
7344 unsigned bytes_in_chunk = 0;
7345 unsigned char c;
7346 int escape;
7347
7348 for (; s < limit; s++)
7349 {
7350 const char *p;
7351
7352 if (bytes_in_chunk >= 60)
7353 {
7354 putc ('\"', f);
7355 putc ('\n', f);
7356 bytes_in_chunk = 0;
7357 }
7358
7359 if (s > last_null)
7360 {
7361 for (p = s; p < limit && *p != '\0'; p++)
7362 continue;
7363 last_null = p;
7364 }
7365 else
7366 p = last_null;
7367
7368 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7369 {
7370 if (bytes_in_chunk > 0)
7371 {
7372 putc ('\"', f);
7373 putc ('\n', f);
7374 bytes_in_chunk = 0;
7375 }
7376
7377 default_elf_asm_output_limited_string (f, s);
7378 s = p;
7379 }
7380 else
7381 {
7382 if (bytes_in_chunk == 0)
7383 fputs (ASCII_DATA_ASM_OP "\"", f);
7384
7385 c = *s;
7386 escape = ELF_ASCII_ESCAPES[c];
7387 switch (escape)
7388 {
7389 case 0:
7390 putc (c, f);
7391 bytes_in_chunk++;
7392 break;
7393 case 1:
7394 /* TODO: Print in hex with fast function, important for -flto. */
7395 fprintf (f, "\\%03o", c);
7396 bytes_in_chunk += 4;
7397 break;
7398 default:
7399 putc ('\\', f);
7400 putc (escape, f);
7401 bytes_in_chunk += 2;
7402 break;
7403 }
7404
7405 }
7406 }
7407
7408 if (bytes_in_chunk > 0)
7409 {
7410 putc ('\"', f);
7411 putc ('\n', f);
7412 }
7413 }
7414 #endif
7415
7416 static GTY(()) section *elf_init_array_section;
7417 static GTY(()) section *elf_fini_array_section;
7418
7419 static section *
7420 get_elf_initfini_array_priority_section (int priority,
7421 bool constructor_p)
7422 {
7423 section *sec;
7424 if (priority != DEFAULT_INIT_PRIORITY)
7425 {
7426 char buf[18];
7427 sprintf (buf, "%s.%.5u",
7428 constructor_p ? ".init_array" : ".fini_array",
7429 priority);
7430 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7431 }
7432 else
7433 {
7434 if (constructor_p)
7435 {
7436 if (elf_init_array_section == NULL)
7437 elf_init_array_section
7438 = get_section (".init_array",
7439 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7440 sec = elf_init_array_section;
7441 }
7442 else
7443 {
7444 if (elf_fini_array_section == NULL)
7445 elf_fini_array_section
7446 = get_section (".fini_array",
7447 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7448 sec = elf_fini_array_section;
7449 }
7450 }
7451 return sec;
7452 }
7453
7454 /* Use .init_array section for constructors. */
7455
7456 void
7457 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7458 {
7459 section *sec = get_elf_initfini_array_priority_section (priority,
7460 true);
7461 assemble_addr_to_section (symbol, sec);
7462 }
7463
7464 /* Use .fini_array section for destructors. */
7465
7466 void
7467 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7468 {
7469 section *sec = get_elf_initfini_array_priority_section (priority,
7470 false);
7471 assemble_addr_to_section (symbol, sec);
7472 }
7473
7474 /* Default TARGET_ASM_OUTPUT_IDENT hook.
7475
7476 This is a bit of a cheat. The real default is a no-op, but this
7477 hook is the default for all targets with a .ident directive. */
7478
7479 void
7480 default_asm_output_ident_directive (const char *ident_str)
7481 {
7482 const char *ident_asm_op = "\t.ident\t";
7483
7484 /* If we are still in the front end, do not write out the string
7485 to asm_out_file. Instead, add a fake top-level asm statement.
7486 This allows the front ends to use this hook without actually
7487 writing to asm_out_file, to handle #ident or Pragma Ident. */
7488 if (cgraph_state == CGRAPH_STATE_PARSING)
7489 {
7490 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
7491 add_asm_node (build_string (strlen (buf), buf));
7492 }
7493 else
7494 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
7495 }
7496
7497 #include "gt-varasm.h"