cppbuiltin.c (define_builtin_macros_for_type_sizes): Round pointer size up to a power...
[gcc.git] / gcc / varasm.c
1 /* Output variables, constants and external declarations, for GNU compiler.
2 Copyright (C) 1987-2014 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 "stor-layout.h"
35 #include "stringpool.h"
36 #include "varasm.h"
37 #include "flags.h"
38 #include "function.h"
39 #include "expr.h"
40 #include "hard-reg-set.h"
41 #include "regs.h"
42 #include "output.h"
43 #include "diagnostic-core.h"
44 #include "hashtab.h"
45 #include "ggc.h"
46 #include "langhooks.h"
47 #include "tm_p.h"
48 #include "debug.h"
49 #include "target.h"
50 #include "common/common-target.h"
51 #include "targhooks.h"
52 #include "cgraph.h"
53 #include "hash-set.h"
54 #include "asan.h"
55 #include "basic-block.h"
56 #include "rtl-iter.h"
57
58 #ifdef XCOFF_DEBUGGING_INFO
59 #include "xcoffout.h" /* Needed for external data
60 declarations for e.g. AIX 4.x. */
61 #endif
62
63 /* The (assembler) name of the first globally-visible object output. */
64 extern GTY(()) const char *first_global_object_name;
65 extern GTY(()) const char *weak_global_object_name;
66
67 const char *first_global_object_name;
68 const char *weak_global_object_name;
69
70 struct addr_const;
71 struct constant_descriptor_rtx;
72 struct rtx_constant_pool;
73
74 #define n_deferred_constants (crtl->varasm.deferred_constants)
75
76 /* Number for making the label on the next
77 constant that is stored in memory. */
78
79 static GTY(()) int const_labelno;
80
81 /* Carry information from ASM_DECLARE_OBJECT_NAME
82 to ASM_FINISH_DECLARE_OBJECT. */
83
84 int size_directive_output;
85
86 /* The last decl for which assemble_variable was called,
87 if it did ASM_DECLARE_OBJECT_NAME.
88 If the last call to assemble_variable didn't do that,
89 this holds 0. */
90
91 tree last_assemble_variable_decl;
92
93 /* The following global variable indicates if the first basic block
94 in a function belongs to the cold partition or not. */
95
96 bool first_function_block_is_cold;
97
98 /* We give all constants their own alias set. Perhaps redundant with
99 MEM_READONLY_P, but pre-dates it. */
100
101 static alias_set_type const_alias_set;
102
103 /* Whether we saw any functions with no_split_stack. */
104
105 static bool saw_no_split_stack;
106
107 static const char *strip_reg_name (const char *);
108 static int contains_pointers_p (tree);
109 #ifdef ASM_OUTPUT_EXTERNAL
110 static bool incorporeal_function_p (tree);
111 #endif
112 static void decode_addr_const (tree, struct addr_const *);
113 static hashval_t const_desc_hash (const void *);
114 static int const_desc_eq (const void *, const void *);
115 static hashval_t const_hash_1 (const tree);
116 static int compare_constant (const tree, const tree);
117 static void output_constant_def_contents (rtx);
118 static void output_addressed_constants (tree);
119 static unsigned HOST_WIDE_INT output_constant (tree, unsigned HOST_WIDE_INT,
120 unsigned int);
121 static void globalize_decl (tree);
122 static bool decl_readonly_section_1 (enum section_category);
123 #ifdef BSS_SECTION_ASM_OP
124 #ifdef ASM_OUTPUT_ALIGNED_BSS
125 static void asm_output_aligned_bss (FILE *, tree, const char *,
126 unsigned HOST_WIDE_INT, int)
127 ATTRIBUTE_UNUSED;
128 #endif
129 #endif /* BSS_SECTION_ASM_OP */
130 static void mark_weak (tree);
131 static void output_constant_pool (const char *, tree);
132 \f
133 /* Well-known sections, each one associated with some sort of *_ASM_OP. */
134 section *text_section;
135 section *data_section;
136 section *readonly_data_section;
137 section *sdata_section;
138 section *ctors_section;
139 section *dtors_section;
140 section *bss_section;
141 section *sbss_section;
142
143 /* Various forms of common section. All are guaranteed to be nonnull. */
144 section *tls_comm_section;
145 section *comm_section;
146 section *lcomm_section;
147
148 /* A SECTION_NOSWITCH section used for declaring global BSS variables.
149 May be null. */
150 section *bss_noswitch_section;
151
152 /* The section that holds the main exception table, when known. The section
153 is set either by the target's init_sections hook or by the first call to
154 switch_to_exception_section. */
155 section *exception_section;
156
157 /* The section that holds the DWARF2 frame unwind information, when known.
158 The section is set either by the target's init_sections hook or by the
159 first call to switch_to_eh_frame_section. */
160 section *eh_frame_section;
161
162 /* asm_out_file's current section. This is NULL if no section has yet
163 been selected or if we lose track of what the current section is. */
164 section *in_section;
165
166 /* True if code for the current function is currently being directed
167 at the cold section. */
168 bool in_cold_section_p;
169
170 /* A linked list of all the unnamed sections. */
171 static GTY(()) section *unnamed_sections;
172
173 /* Return a nonzero value if DECL has a section attribute. */
174 #define IN_NAMED_SECTION(DECL) \
175 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \
176 && DECL_SECTION_NAME (DECL) != NULL)
177
178 /* Hash table of named sections. */
179 static GTY((param_is (section))) htab_t section_htab;
180
181 /* A table of object_blocks, indexed by section. */
182 static GTY((param_is (struct object_block))) htab_t object_block_htab;
183
184 /* The next number to use for internal anchor labels. */
185 static GTY(()) int anchor_labelno;
186
187 /* A pool of constants that can be shared between functions. */
188 static GTY(()) struct rtx_constant_pool *shared_constant_pool;
189
190 /* Helper routines for maintaining section_htab. */
191
192 static int
193 section_entry_eq (const void *p1, const void *p2)
194 {
195 const section *old = (const section *) p1;
196 const char *new_name = (const char *) p2;
197
198 return strcmp (old->named.name, new_name) == 0;
199 }
200
201 static hashval_t
202 section_entry_hash (const void *p)
203 {
204 const section *old = (const section *) p;
205 return htab_hash_string (old->named.name);
206 }
207
208 /* Return a hash value for section SECT. */
209
210 static hashval_t
211 hash_section (section *sect)
212 {
213 if (sect->common.flags & SECTION_NAMED)
214 return htab_hash_string (sect->named.name);
215 return sect->common.flags;
216 }
217
218 /* Helper routines for maintaining object_block_htab. */
219
220 static int
221 object_block_entry_eq (const void *p1, const void *p2)
222 {
223 const struct object_block *old = (const struct object_block *) p1;
224 const section *new_section = (const section *) p2;
225
226 return old->sect == new_section;
227 }
228
229 static hashval_t
230 object_block_entry_hash (const void *p)
231 {
232 const struct object_block *old = (const struct object_block *) p;
233 return hash_section (old->sect);
234 }
235
236 /* Return a new unnamed section with the given fields. */
237
238 section *
239 get_unnamed_section (unsigned int flags, void (*callback) (const void *),
240 const void *data)
241 {
242 section *sect;
243
244 sect = ggc_alloc<section> ();
245 sect->unnamed.common.flags = flags | SECTION_UNNAMED;
246 sect->unnamed.callback = callback;
247 sect->unnamed.data = data;
248 sect->unnamed.next = unnamed_sections;
249
250 unnamed_sections = sect;
251 return sect;
252 }
253
254 /* Return a SECTION_NOSWITCH section with the given fields. */
255
256 static section *
257 get_noswitch_section (unsigned int flags, noswitch_section_callback callback)
258 {
259 section *sect;
260
261 sect = ggc_alloc<section> ();
262 sect->noswitch.common.flags = flags | SECTION_NOSWITCH;
263 sect->noswitch.callback = callback;
264
265 return sect;
266 }
267
268 /* Return the named section structure associated with NAME. Create
269 a new section with the given fields if no such structure exists. */
270
271 section *
272 get_section (const char *name, unsigned int flags, tree decl)
273 {
274 section *sect, **slot;
275
276 slot = (section **)
277 htab_find_slot_with_hash (section_htab, name,
278 htab_hash_string (name), INSERT);
279 flags |= SECTION_NAMED;
280 if (*slot == NULL)
281 {
282 sect = ggc_alloc<section> ();
283 sect->named.common.flags = flags;
284 sect->named.name = ggc_strdup (name);
285 sect->named.decl = decl;
286 *slot = sect;
287 }
288 else
289 {
290 sect = *slot;
291 if ((sect->common.flags & ~SECTION_DECLARED) != flags
292 && ((sect->common.flags | flags) & SECTION_OVERRIDE) == 0)
293 {
294 /* It is fine if one of the section flags is
295 SECTION_WRITE | SECTION_RELRO and the other has none of these
296 flags (i.e. read-only) in named sections and either the
297 section hasn't been declared yet or has been declared as writable.
298 In that case just make sure the resulting flags are
299 SECTION_WRITE | SECTION_RELRO, ie. writable only because of
300 relocations. */
301 if (((sect->common.flags ^ flags) & (SECTION_WRITE | SECTION_RELRO))
302 == (SECTION_WRITE | SECTION_RELRO)
303 && (sect->common.flags
304 & ~(SECTION_DECLARED | SECTION_WRITE | SECTION_RELRO))
305 == (flags & ~(SECTION_WRITE | SECTION_RELRO))
306 && ((sect->common.flags & SECTION_DECLARED) == 0
307 || (sect->common.flags & SECTION_WRITE)))
308 {
309 sect->common.flags |= (SECTION_WRITE | SECTION_RELRO);
310 return sect;
311 }
312 /* Sanity check user variables for flag changes. */
313 if (sect->named.decl != NULL
314 && DECL_P (sect->named.decl)
315 && decl != sect->named.decl)
316 {
317 if (decl != NULL && DECL_P (decl))
318 error ("%+D causes a section type conflict with %D",
319 decl, sect->named.decl);
320 else
321 error ("section type conflict with %D", sect->named.decl);
322 inform (DECL_SOURCE_LOCATION (sect->named.decl),
323 "%qD was declared here", sect->named.decl);
324 }
325 else if (decl != NULL && DECL_P (decl))
326 error ("%+D causes a section type conflict", decl);
327 else
328 error ("section type conflict");
329 /* Make sure we don't error about one section multiple times. */
330 sect->common.flags |= SECTION_OVERRIDE;
331 }
332 }
333 return sect;
334 }
335
336 /* Return true if the current compilation mode benefits from having
337 objects grouped into blocks. */
338
339 static bool
340 use_object_blocks_p (void)
341 {
342 return flag_section_anchors;
343 }
344
345 /* Return the object_block structure for section SECT. Create a new
346 structure if we haven't created one already. Return null if SECT
347 itself is null. */
348
349 static struct object_block *
350 get_block_for_section (section *sect)
351 {
352 struct object_block *block;
353 void **slot;
354
355 if (sect == NULL)
356 return NULL;
357
358 slot = htab_find_slot_with_hash (object_block_htab, sect,
359 hash_section (sect), INSERT);
360 block = (struct object_block *) *slot;
361 if (block == NULL)
362 {
363 block = ggc_cleared_alloc<object_block> ();
364 block->sect = sect;
365 *slot = block;
366 }
367 return block;
368 }
369
370 /* Create a symbol with label LABEL and place it at byte offset
371 OFFSET in BLOCK. OFFSET can be negative if the symbol's offset
372 is not yet known. LABEL must be a garbage-collected string. */
373
374 static rtx
375 create_block_symbol (const char *label, struct object_block *block,
376 HOST_WIDE_INT offset)
377 {
378 rtx symbol;
379 unsigned int size;
380
381 /* Create the extended SYMBOL_REF. */
382 size = RTX_HDR_SIZE + sizeof (struct block_symbol);
383 symbol = (rtx) ggc_internal_alloc (size);
384
385 /* Initialize the normal SYMBOL_REF fields. */
386 memset (symbol, 0, size);
387 PUT_CODE (symbol, SYMBOL_REF);
388 PUT_MODE (symbol, Pmode);
389 XSTR (symbol, 0) = label;
390 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_HAS_BLOCK_INFO;
391
392 /* Initialize the block_symbol stuff. */
393 SYMBOL_REF_BLOCK (symbol) = block;
394 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
395
396 return symbol;
397 }
398
399 /* Return a section with a particular name and with whatever SECTION_*
400 flags section_type_flags deems appropriate. The name of the section
401 is taken from NAME if nonnull, otherwise it is taken from DECL's
402 DECL_SECTION_NAME. DECL is the decl associated with the section
403 (see the section comment for details) and RELOC is as for
404 section_type_flags. */
405
406 section *
407 get_named_section (tree decl, const char *name, int reloc)
408 {
409 unsigned int flags;
410
411 if (name == NULL)
412 {
413 gcc_assert (decl && DECL_P (decl) && DECL_SECTION_NAME (decl));
414 name = DECL_SECTION_NAME (decl);
415 }
416
417 flags = targetm.section_type_flags (decl, name, reloc);
418 return get_section (name, flags, decl);
419 }
420
421 /* Worker for resolve_unique_section. */
422
423 static bool
424 set_implicit_section (struct symtab_node *n, void *data ATTRIBUTE_UNUSED)
425 {
426 n->implicit_section = true;
427 return false;
428 }
429
430 /* If required, set DECL_SECTION_NAME to a unique name. */
431
432 void
433 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
434 int flag_function_or_data_sections)
435 {
436 if (DECL_SECTION_NAME (decl) == NULL
437 && targetm_common.have_named_sections
438 && (flag_function_or_data_sections
439 || DECL_COMDAT_GROUP (decl)))
440 {
441 targetm.asm_out.unique_section (decl, reloc);
442 if (DECL_SECTION_NAME (decl))
443 symtab_node::get (decl)->call_for_symbol_and_aliases
444 (set_implicit_section, NULL, true);
445 }
446 }
447
448 #ifdef BSS_SECTION_ASM_OP
449
450 #ifdef ASM_OUTPUT_ALIGNED_BSS
451
452 /* Utility function for targets to use in implementing
453 ASM_OUTPUT_ALIGNED_BSS.
454 ??? It is believed that this function will work in most cases so such
455 support is localized here. */
456
457 static void
458 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
459 const char *name, unsigned HOST_WIDE_INT size,
460 int align)
461 {
462 switch_to_section (bss_section);
463 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
464 #ifdef ASM_DECLARE_OBJECT_NAME
465 last_assemble_variable_decl = decl;
466 ASM_DECLARE_OBJECT_NAME (file, name, decl);
467 #else
468 /* Standard thing is just output label for the object. */
469 ASM_OUTPUT_LABEL (file, name);
470 #endif /* ASM_DECLARE_OBJECT_NAME */
471 ASM_OUTPUT_SKIP (file, size ? size : 1);
472 }
473
474 #endif
475
476 #endif /* BSS_SECTION_ASM_OP */
477
478 #ifndef USE_SELECT_SECTION_FOR_FUNCTIONS
479 /* Return the hot section for function DECL. Return text_section for
480 null DECLs. */
481
482 static section *
483 hot_function_section (tree decl)
484 {
485 if (decl != NULL_TREE
486 && DECL_SECTION_NAME (decl) != NULL
487 && targetm_common.have_named_sections)
488 return get_named_section (decl, NULL, 0);
489 else
490 return text_section;
491 }
492 #endif
493
494 /* Return section for TEXT_SECTION_NAME if DECL or DECL_SECTION_NAME (DECL)
495 is NULL.
496
497 When DECL_SECTION_NAME is non-NULL and it is implicit section and
498 NAMED_SECTION_SUFFIX is non-NULL, then produce section called
499 concatenate the name with NAMED_SECTION_SUFFIX.
500 Otherwise produce "TEXT_SECTION_NAME.IMPLICIT_NAME". */
501
502 section *
503 get_named_text_section (tree decl,
504 const char *text_section_name,
505 const char *named_section_suffix)
506 {
507 if (decl && DECL_SECTION_NAME (decl))
508 {
509 if (named_section_suffix)
510 {
511 const char *dsn = DECL_SECTION_NAME (decl);
512 const char *stripped_name;
513 char *name, *buffer;
514
515 name = (char *) alloca (strlen (dsn) + 1);
516 memcpy (name, dsn,
517 strlen (dsn) + 1);
518
519 stripped_name = targetm.strip_name_encoding (name);
520
521 buffer = ACONCAT ((stripped_name, named_section_suffix, NULL));
522 return get_named_section (decl, buffer, 0);
523 }
524 else if (symtab_node::get (decl)->implicit_section)
525 {
526 const char *name;
527
528 /* Do not try to split gnu_linkonce functions. This gets somewhat
529 slipperly. */
530 if (DECL_COMDAT_GROUP (decl) && !HAVE_COMDAT_GROUP)
531 return NULL;
532 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
533 name = targetm.strip_name_encoding (name);
534 return get_named_section (decl, ACONCAT ((text_section_name, ".",
535 name, NULL)), 0);
536 }
537 else
538 return NULL;
539 }
540 return get_named_section (decl, text_section_name, 0);
541 }
542
543 /* Choose named function section based on its frequency. */
544
545 section *
546 default_function_section (tree decl, enum node_frequency freq,
547 bool startup, bool exit)
548 {
549 #if defined HAVE_LD_EH_GC_SECTIONS && defined HAVE_LD_EH_GC_SECTIONS_BUG
550 /* Old GNU linkers have buggy --gc-section support, which sometimes
551 results in .gcc_except_table* sections being garbage collected. */
552 if (decl
553 && symtab_node::get (decl)->implicit_section)
554 return NULL;
555 #endif
556
557 if (!flag_reorder_functions
558 || !targetm_common.have_named_sections)
559 return NULL;
560 /* Startup code should go to startup subsection unless it is
561 unlikely executed (this happens especially with function splitting
562 where we can split away unnecessary parts of static constructors. */
563 if (startup && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
564 {
565 /* If we do have a profile or(and) LTO phase is executed, we do not need
566 these ELF section. */
567 if (!in_lto_p || !flag_profile_values)
568 return get_named_text_section (decl, ".text.startup", NULL);
569 else
570 return NULL;
571 }
572
573 /* Similarly for exit. */
574 if (exit && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
575 return get_named_text_section (decl, ".text.exit", NULL);
576
577 /* Group cold functions together, similarly for hot code. */
578 switch (freq)
579 {
580 case NODE_FREQUENCY_UNLIKELY_EXECUTED:
581 return get_named_text_section (decl, ".text.unlikely", NULL);
582 case NODE_FREQUENCY_HOT:
583 /* If we do have a profile or(and) LTO phase is executed, we do not need
584 these ELF section. */
585 if (!in_lto_p || !flag_profile_values)
586 return get_named_text_section (decl, ".text.hot", NULL);
587 default:
588 return NULL;
589 }
590 }
591
592 /* Return the section for function DECL.
593
594 If DECL is NULL_TREE, return the text section. We can be passed
595 NULL_TREE under some circumstances by dbxout.c at least.
596
597 If FORCE_COLD is true, return cold function section ignoring
598 the frequency info of cgraph_node. */
599
600 static section *
601 function_section_1 (tree decl, bool force_cold)
602 {
603 section *section = NULL;
604 enum node_frequency freq = NODE_FREQUENCY_NORMAL;
605 bool startup = false, exit = false;
606
607 if (decl)
608 {
609 struct cgraph_node *node = cgraph_node::get (decl);
610
611 if (node)
612 {
613 freq = node->frequency;
614 startup = node->only_called_at_startup;
615 exit = node->only_called_at_exit;
616 }
617 }
618 if (force_cold)
619 freq = NODE_FREQUENCY_UNLIKELY_EXECUTED;
620
621 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
622 if (decl != NULL_TREE
623 && DECL_SECTION_NAME (decl) != NULL)
624 {
625 if (targetm.asm_out.function_section)
626 section = targetm.asm_out.function_section (decl, freq,
627 startup, exit);
628 if (section)
629 return section;
630 return get_named_section (decl, NULL, 0);
631 }
632 else
633 return targetm.asm_out.select_section
634 (decl, freq == NODE_FREQUENCY_UNLIKELY_EXECUTED,
635 DECL_ALIGN (decl));
636 #else
637 if (targetm.asm_out.function_section)
638 section = targetm.asm_out.function_section (decl, freq, startup, exit);
639 if (section)
640 return section;
641 return hot_function_section (decl);
642 #endif
643 }
644
645 /* Return the section for function DECL.
646
647 If DECL is NULL_TREE, return the text section. We can be passed
648 NULL_TREE under some circumstances by dbxout.c at least. */
649
650 section *
651 function_section (tree decl)
652 {
653 /* Handle cases where function splitting code decides
654 to put function entry point into unlikely executed section
655 despite the fact that the function itself is not cold
656 (i.e. it is called rarely but contains a hot loop that is
657 better to live in hot subsection for the code locality). */
658 return function_section_1 (decl,
659 first_function_block_is_cold);
660 }
661
662 /* Return the section for the current function, take IN_COLD_SECTION_P
663 into account. */
664
665 section *
666 current_function_section (void)
667 {
668 return function_section_1 (current_function_decl, in_cold_section_p);
669 }
670
671 /* Tell assembler to switch to unlikely-to-be-executed text section. */
672
673 section *
674 unlikely_text_section (void)
675 {
676 return function_section_1 (current_function_decl, true);
677 }
678
679 /* When called within a function context, return true if the function
680 has been assigned a cold text section and if SECT is that section.
681 When called outside a function context, return true if SECT is the
682 default cold section. */
683
684 bool
685 unlikely_text_section_p (section *sect)
686 {
687 return sect == function_section_1 (current_function_decl, true);
688 }
689
690 /* Return the read-only data section associated with function DECL. */
691
692 section *
693 default_function_rodata_section (tree decl)
694 {
695 if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
696 {
697 const char *name = DECL_SECTION_NAME (decl);
698
699 if (DECL_COMDAT_GROUP (decl) && HAVE_COMDAT_GROUP)
700 {
701 const char *dot;
702 size_t len;
703 char* rname;
704
705 dot = strchr (name + 1, '.');
706 if (!dot)
707 dot = name;
708 len = strlen (dot) + 8;
709 rname = (char *) alloca (len);
710
711 strcpy (rname, ".rodata");
712 strcat (rname, dot);
713 return get_section (rname, SECTION_LINKONCE, decl);
714 }
715 /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo. */
716 else if (DECL_COMDAT_GROUP (decl)
717 && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
718 {
719 size_t len = strlen (name) + 1;
720 char *rname = (char *) alloca (len);
721
722 memcpy (rname, name, len);
723 rname[14] = 'r';
724 return get_section (rname, SECTION_LINKONCE, decl);
725 }
726 /* For .text.foo we want to use .rodata.foo. */
727 else if (flag_function_sections && flag_data_sections
728 && strncmp (name, ".text.", 6) == 0)
729 {
730 size_t len = strlen (name) + 1;
731 char *rname = (char *) alloca (len + 2);
732
733 memcpy (rname, ".rodata", 7);
734 memcpy (rname + 7, name + 5, len - 5);
735 return get_section (rname, 0, decl);
736 }
737 }
738
739 return readonly_data_section;
740 }
741
742 /* Return the read-only data section associated with function DECL
743 for targets where that section should be always the single
744 readonly data section. */
745
746 section *
747 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
748 {
749 return readonly_data_section;
750 }
751
752 /* Return the section to use for string merging. */
753
754 static section *
755 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
756 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
757 unsigned int flags ATTRIBUTE_UNUSED)
758 {
759 HOST_WIDE_INT len;
760
761 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
762 && TREE_CODE (decl) == STRING_CST
763 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
764 && align <= 256
765 && (len = int_size_in_bytes (TREE_TYPE (decl))) > 0
766 && TREE_STRING_LENGTH (decl) >= len)
767 {
768 enum machine_mode mode;
769 unsigned int modesize;
770 const char *str;
771 HOST_WIDE_INT i;
772 int j, unit;
773 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
774 char *name = (char *) alloca (strlen (prefix) + 30);
775
776 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
777 modesize = GET_MODE_BITSIZE (mode);
778 if (modesize >= 8 && modesize <= 256
779 && (modesize & (modesize - 1)) == 0)
780 {
781 if (align < modesize)
782 align = modesize;
783
784 str = TREE_STRING_POINTER (decl);
785 unit = GET_MODE_SIZE (mode);
786
787 /* Check for embedded NUL characters. */
788 for (i = 0; i < len; i += unit)
789 {
790 for (j = 0; j < unit; j++)
791 if (str[i + j] != '\0')
792 break;
793 if (j == unit)
794 break;
795 }
796 if (i == len - unit)
797 {
798 sprintf (name, "%s.str%d.%d", prefix,
799 modesize / 8, (int) (align / 8));
800 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
801 return get_section (name, flags, NULL);
802 }
803 }
804 }
805
806 return readonly_data_section;
807 }
808
809 /* Return the section to use for constant merging. */
810
811 section *
812 mergeable_constant_section (enum machine_mode mode ATTRIBUTE_UNUSED,
813 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
814 unsigned int flags ATTRIBUTE_UNUSED)
815 {
816 unsigned int modesize = GET_MODE_BITSIZE (mode);
817
818 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
819 && mode != VOIDmode
820 && mode != BLKmode
821 && modesize <= align
822 && align >= 8
823 && align <= 256
824 && (align & (align - 1)) == 0)
825 {
826 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
827 char *name = (char *) alloca (strlen (prefix) + 30);
828
829 sprintf (name, "%s.cst%d", prefix, (int) (align / 8));
830 flags |= (align / 8) | SECTION_MERGE;
831 return get_section (name, flags, NULL);
832 }
833 return readonly_data_section;
834 }
835 \f
836 /* Given NAME, a putative register name, discard any customary prefixes. */
837
838 static const char *
839 strip_reg_name (const char *name)
840 {
841 #ifdef REGISTER_PREFIX
842 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
843 name += strlen (REGISTER_PREFIX);
844 #endif
845 if (name[0] == '%' || name[0] == '#')
846 name++;
847 return name;
848 }
849 \f
850 /* The user has asked for a DECL to have a particular name. Set (or
851 change) it in such a way that we don't prefix an underscore to
852 it. */
853 void
854 set_user_assembler_name (tree decl, const char *name)
855 {
856 char *starred = (char *) alloca (strlen (name) + 2);
857 starred[0] = '*';
858 strcpy (starred + 1, name);
859 symtab->change_decl_assembler_name (decl, get_identifier (starred));
860 SET_DECL_RTL (decl, NULL_RTX);
861 }
862 \f
863 /* Decode an `asm' spec for a declaration as a register name.
864 Return the register number, or -1 if nothing specified,
865 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
866 or -3 if ASMSPEC is `cc' and is not recognized,
867 or -4 if ASMSPEC is `memory' and is not recognized.
868 Accept an exact spelling or a decimal number.
869 Prefixes such as % are optional. */
870
871 int
872 decode_reg_name_and_count (const char *asmspec, int *pnregs)
873 {
874 /* Presume just one register is clobbered. */
875 *pnregs = 1;
876
877 if (asmspec != 0)
878 {
879 int i;
880
881 /* Get rid of confusing prefixes. */
882 asmspec = strip_reg_name (asmspec);
883
884 /* Allow a decimal number as a "register name". */
885 for (i = strlen (asmspec) - 1; i >= 0; i--)
886 if (! ISDIGIT (asmspec[i]))
887 break;
888 if (asmspec[0] != 0 && i < 0)
889 {
890 i = atoi (asmspec);
891 if (i < FIRST_PSEUDO_REGISTER && i >= 0)
892 return i;
893 else
894 return -2;
895 }
896
897 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
898 if (reg_names[i][0]
899 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
900 return i;
901
902 #ifdef OVERLAPPING_REGISTER_NAMES
903 {
904 static const struct
905 {
906 const char *const name;
907 const int number;
908 const int nregs;
909 } table[] = OVERLAPPING_REGISTER_NAMES;
910
911 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
912 if (table[i].name[0]
913 && ! strcmp (asmspec, table[i].name))
914 {
915 *pnregs = table[i].nregs;
916 return table[i].number;
917 }
918 }
919 #endif /* OVERLAPPING_REGISTER_NAMES */
920
921 #ifdef ADDITIONAL_REGISTER_NAMES
922 {
923 static const struct { const char *const name; const int number; } table[]
924 = ADDITIONAL_REGISTER_NAMES;
925
926 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
927 if (table[i].name[0]
928 && ! strcmp (asmspec, table[i].name))
929 return table[i].number;
930 }
931 #endif /* ADDITIONAL_REGISTER_NAMES */
932
933 if (!strcmp (asmspec, "memory"))
934 return -4;
935
936 if (!strcmp (asmspec, "cc"))
937 return -3;
938
939 return -2;
940 }
941
942 return -1;
943 }
944
945 int
946 decode_reg_name (const char *name)
947 {
948 int count;
949 return decode_reg_name_and_count (name, &count);
950 }
951
952 \f
953 /* Return true if DECL's initializer is suitable for a BSS section. */
954
955 bool
956 bss_initializer_p (const_tree decl)
957 {
958 return (DECL_INITIAL (decl) == NULL
959 /* In LTO we have no errors in program; error_mark_node is used
960 to mark offlined constructors. */
961 || (DECL_INITIAL (decl) == error_mark_node
962 && !in_lto_p)
963 || (flag_zero_initialized_in_bss
964 /* Leave constant zeroes in .rodata so they
965 can be shared. */
966 && !TREE_READONLY (decl)
967 && initializer_zerop (DECL_INITIAL (decl))));
968 }
969
970 /* Compute the alignment of variable specified by DECL.
971 DONT_OUTPUT_DATA is from assemble_variable. */
972
973 void
974 align_variable (tree decl, bool dont_output_data)
975 {
976 unsigned int align = DECL_ALIGN (decl);
977
978 /* In the case for initialing an array whose length isn't specified,
979 where we have not yet been able to do the layout,
980 figure out the proper alignment now. */
981 if (dont_output_data && DECL_SIZE (decl) == 0
982 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
983 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
984
985 /* Some object file formats have a maximum alignment which they support.
986 In particular, a.out format supports a maximum alignment of 4. */
987 if (align > MAX_OFILE_ALIGNMENT)
988 {
989 error ("alignment of %q+D is greater than maximum object "
990 "file alignment %d", decl,
991 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
992 align = MAX_OFILE_ALIGNMENT;
993 }
994
995 if (! DECL_USER_ALIGN (decl))
996 {
997 #ifdef DATA_ABI_ALIGNMENT
998 unsigned int data_abi_align
999 = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1000 /* For backwards compatibility, don't assume the ABI alignment for
1001 TLS variables. */
1002 if (! DECL_THREAD_LOCAL_P (decl) || data_abi_align <= BITS_PER_WORD)
1003 align = data_abi_align;
1004 #endif
1005
1006 /* On some machines, it is good to increase alignment sometimes.
1007 But as DECL_ALIGN is used both for actually emitting the variable
1008 and for code accessing the variable as guaranteed alignment, we
1009 can only increase the alignment if it is a performance optimization
1010 if the references to it must bind to the current definition. */
1011 if (decl_binds_to_current_def_p (decl)
1012 && !DECL_VIRTUAL_P (decl))
1013 {
1014 #ifdef DATA_ALIGNMENT
1015 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1016 /* Don't increase alignment too much for TLS variables - TLS space
1017 is too precious. */
1018 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1019 align = data_align;
1020 #endif
1021 #ifdef CONSTANT_ALIGNMENT
1022 if (DECL_INITIAL (decl) != 0
1023 /* In LTO we have no errors in program; error_mark_node is used
1024 to mark offlined constructors. */
1025 && (in_lto_p || DECL_INITIAL (decl) != error_mark_node))
1026 {
1027 unsigned int const_align
1028 = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
1029 /* Don't increase alignment too much for TLS variables - TLS
1030 space is too precious. */
1031 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1032 align = const_align;
1033 }
1034 #endif
1035 }
1036 }
1037
1038 /* Reset the alignment in case we have made it tighter, so we can benefit
1039 from it in get_pointer_alignment. */
1040 DECL_ALIGN (decl) = align;
1041 }
1042
1043 /* Return DECL_ALIGN (decl), possibly increased for optimization purposes
1044 beyond what align_variable returned. */
1045
1046 static unsigned int
1047 get_variable_align (tree decl)
1048 {
1049 unsigned int align = DECL_ALIGN (decl);
1050
1051 /* For user aligned vars or static vars align_variable already did
1052 everything. */
1053 if (DECL_USER_ALIGN (decl) || !TREE_PUBLIC (decl))
1054 return align;
1055
1056 #ifdef DATA_ABI_ALIGNMENT
1057 if (DECL_THREAD_LOCAL_P (decl))
1058 align = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1059 #endif
1060
1061 /* For decls that bind to the current definition, align_variable
1062 did also everything, except for not assuming ABI required alignment
1063 of TLS variables. For other vars, increase the alignment here
1064 as an optimization. */
1065 if (!decl_binds_to_current_def_p (decl))
1066 {
1067 /* On some machines, it is good to increase alignment sometimes. */
1068 #ifdef DATA_ALIGNMENT
1069 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1070 /* Don't increase alignment too much for TLS variables - TLS space
1071 is too precious. */
1072 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1073 align = data_align;
1074 #endif
1075 #ifdef CONSTANT_ALIGNMENT
1076 if (DECL_INITIAL (decl) != 0
1077 /* In LTO we have no errors in program; error_mark_node is used
1078 to mark offlined constructors. */
1079 && (in_lto_p || DECL_INITIAL (decl) != error_mark_node))
1080 {
1081 unsigned int const_align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl),
1082 align);
1083 /* Don't increase alignment too much for TLS variables - TLS space
1084 is too precious. */
1085 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1086 align = const_align;
1087 }
1088 #endif
1089 }
1090
1091 return align;
1092 }
1093
1094 /* Return the section into which the given VAR_DECL or CONST_DECL
1095 should be placed. PREFER_NOSWITCH_P is true if a noswitch
1096 section should be used wherever possible. */
1097
1098 section *
1099 get_variable_section (tree decl, bool prefer_noswitch_p)
1100 {
1101 addr_space_t as = ADDR_SPACE_GENERIC;
1102 int reloc;
1103 varpool_node *vnode = varpool_node::get (decl);
1104 if (vnode)
1105 {
1106 vnode = vnode->ultimate_alias_target ();
1107 decl = vnode->decl;
1108 }
1109
1110 if (TREE_TYPE (decl) != error_mark_node)
1111 as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1112
1113 /* We need the constructor to figure out reloc flag. */
1114 if (vnode)
1115 vnode->get_constructor ();
1116
1117 if (DECL_COMMON (decl))
1118 {
1119 /* If the decl has been given an explicit section name, or it resides
1120 in a non-generic address space, then it isn't common, and shouldn't
1121 be handled as such. */
1122 gcc_assert (DECL_SECTION_NAME (decl) == NULL
1123 && ADDR_SPACE_GENERIC_P (as));
1124 if (DECL_THREAD_LOCAL_P (decl))
1125 return tls_comm_section;
1126 else if (TREE_PUBLIC (decl) && bss_initializer_p (decl))
1127 return comm_section;
1128 }
1129
1130 if (DECL_INITIAL (decl) == error_mark_node)
1131 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1132 else if (DECL_INITIAL (decl))
1133 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1134 else
1135 reloc = 0;
1136
1137 resolve_unique_section (decl, reloc, flag_data_sections);
1138 if (IN_NAMED_SECTION (decl))
1139 return get_named_section (decl, NULL, reloc);
1140
1141 if (ADDR_SPACE_GENERIC_P (as)
1142 && !DECL_THREAD_LOCAL_P (decl)
1143 && !(prefer_noswitch_p && targetm.have_switchable_bss_sections)
1144 && bss_initializer_p (decl))
1145 {
1146 if (!TREE_PUBLIC (decl)
1147 && !((flag_sanitize & SANITIZE_ADDRESS)
1148 && asan_protect_global (decl)))
1149 return lcomm_section;
1150 if (bss_noswitch_section)
1151 return bss_noswitch_section;
1152 }
1153
1154 return targetm.asm_out.select_section (decl, reloc,
1155 get_variable_align (decl));
1156 }
1157
1158 /* Return the block into which object_block DECL should be placed. */
1159
1160 static struct object_block *
1161 get_block_for_decl (tree decl)
1162 {
1163 section *sect;
1164
1165 if (TREE_CODE (decl) == VAR_DECL)
1166 {
1167 /* The object must be defined in this translation unit. */
1168 if (DECL_EXTERNAL (decl))
1169 return NULL;
1170
1171 /* There's no point using object blocks for something that is
1172 isolated by definition. */
1173 if (DECL_COMDAT_GROUP (decl))
1174 return NULL;
1175 }
1176
1177 /* We can only calculate block offsets if the decl has a known
1178 constant size. */
1179 if (DECL_SIZE_UNIT (decl) == NULL)
1180 return NULL;
1181 if (!tree_fits_uhwi_p (DECL_SIZE_UNIT (decl)))
1182 return NULL;
1183
1184 /* Find out which section should contain DECL. We cannot put it into
1185 an object block if it requires a standalone definition. */
1186 if (TREE_CODE (decl) == VAR_DECL)
1187 align_variable (decl, 0);
1188 sect = get_variable_section (decl, true);
1189 if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
1190 return NULL;
1191
1192 return get_block_for_section (sect);
1193 }
1194
1195 /* Make sure block symbol SYMBOL is in block BLOCK. */
1196
1197 static void
1198 change_symbol_block (rtx symbol, struct object_block *block)
1199 {
1200 if (block != SYMBOL_REF_BLOCK (symbol))
1201 {
1202 gcc_assert (SYMBOL_REF_BLOCK_OFFSET (symbol) < 0);
1203 SYMBOL_REF_BLOCK (symbol) = block;
1204 }
1205 }
1206
1207 /* Return true if it is possible to put DECL in an object_block. */
1208
1209 static bool
1210 use_blocks_for_decl_p (tree decl)
1211 {
1212 struct symtab_node *snode;
1213
1214 /* Only data DECLs can be placed into object blocks. */
1215 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != CONST_DECL)
1216 return false;
1217
1218 /* Detect decls created by dw2_force_const_mem. Such decls are
1219 special because DECL_INITIAL doesn't specify the decl's true value.
1220 dw2_output_indirect_constants will instead call assemble_variable
1221 with dont_output_data set to 1 and then print the contents itself. */
1222 if (DECL_INITIAL (decl) == decl)
1223 return false;
1224
1225 /* If this decl is an alias, then we don't want to emit a
1226 definition. */
1227 if (TREE_CODE (decl) == VAR_DECL
1228 && (snode = symtab_node::get (decl)) != NULL
1229 && snode->alias)
1230 return false;
1231
1232 return targetm.use_blocks_for_decl_p (decl);
1233 }
1234
1235 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
1236 have static storage duration. In other words, it should not be an
1237 automatic variable, including PARM_DECLs.
1238
1239 There is, however, one exception: this function handles variables
1240 explicitly placed in a particular register by the user.
1241
1242 This is never called for PARM_DECL nodes. */
1243
1244 void
1245 make_decl_rtl (tree decl)
1246 {
1247 const char *name = 0;
1248 int reg_number;
1249 rtx x;
1250
1251 /* Check that we are not being given an automatic variable. */
1252 gcc_assert (TREE_CODE (decl) != PARM_DECL
1253 && TREE_CODE (decl) != RESULT_DECL);
1254
1255 /* A weak alias has TREE_PUBLIC set but not the other bits. */
1256 gcc_assert (TREE_CODE (decl) != VAR_DECL
1257 || TREE_STATIC (decl)
1258 || TREE_PUBLIC (decl)
1259 || DECL_EXTERNAL (decl)
1260 || DECL_REGISTER (decl));
1261
1262 /* And that we were not given a type or a label. */
1263 gcc_assert (TREE_CODE (decl) != TYPE_DECL
1264 && TREE_CODE (decl) != LABEL_DECL);
1265
1266 /* For a duplicate declaration, we can be called twice on the
1267 same DECL node. Don't discard the RTL already made. */
1268 if (DECL_RTL_SET_P (decl))
1269 {
1270 /* If the old RTL had the wrong mode, fix the mode. */
1271 x = DECL_RTL (decl);
1272 if (GET_MODE (x) != DECL_MODE (decl))
1273 SET_DECL_RTL (decl, adjust_address_nv (x, DECL_MODE (decl), 0));
1274
1275 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1276 return;
1277
1278 /* ??? Another way to do this would be to maintain a hashed
1279 table of such critters. Instead of adding stuff to a DECL
1280 to give certain attributes to it, we could use an external
1281 hash map from DECL to set of attributes. */
1282
1283 /* Let the target reassign the RTL if it wants.
1284 This is necessary, for example, when one machine specific
1285 decl attribute overrides another. */
1286 targetm.encode_section_info (decl, DECL_RTL (decl), false);
1287
1288 /* If the symbol has a SYMBOL_REF_BLOCK field, update it based
1289 on the new decl information. */
1290 if (MEM_P (x)
1291 && GET_CODE (XEXP (x, 0)) == SYMBOL_REF
1292 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (x, 0)))
1293 change_symbol_block (XEXP (x, 0), get_block_for_decl (decl));
1294
1295 return;
1296 }
1297
1298 /* If this variable belongs to the global constant pool, retrieve the
1299 pre-computed RTL or recompute it in LTO mode. */
1300 if (TREE_CODE (decl) == VAR_DECL && DECL_IN_CONSTANT_POOL (decl))
1301 {
1302 SET_DECL_RTL (decl, output_constant_def (DECL_INITIAL (decl), 1));
1303 return;
1304 }
1305
1306 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
1307
1308 if (name[0] != '*' && TREE_CODE (decl) != FUNCTION_DECL
1309 && DECL_REGISTER (decl))
1310 {
1311 error ("register name not specified for %q+D", decl);
1312 }
1313 else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1314 {
1315 const char *asmspec = name+1;
1316 enum machine_mode mode = DECL_MODE (decl);
1317 reg_number = decode_reg_name (asmspec);
1318 /* First detect errors in declaring global registers. */
1319 if (reg_number == -1)
1320 error ("register name not specified for %q+D", decl);
1321 else if (reg_number < 0)
1322 error ("invalid register name for %q+D", decl);
1323 else if (mode == BLKmode)
1324 error ("data type of %q+D isn%'t suitable for a register",
1325 decl);
1326 else if (!in_hard_reg_set_p (accessible_reg_set, mode, reg_number))
1327 error ("the register specified for %q+D cannot be accessed"
1328 " by the current target", decl);
1329 else if (!in_hard_reg_set_p (operand_reg_set, mode, reg_number))
1330 error ("the register specified for %q+D is not general enough"
1331 " to be used as a register variable", decl);
1332 else if (!HARD_REGNO_MODE_OK (reg_number, mode))
1333 error ("register specified for %q+D isn%'t suitable for data type",
1334 decl);
1335 /* Now handle properly declared static register variables. */
1336 else
1337 {
1338 int nregs;
1339
1340 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
1341 {
1342 DECL_INITIAL (decl) = 0;
1343 error ("global register variable has initial value");
1344 }
1345 if (TREE_THIS_VOLATILE (decl))
1346 warning (OPT_Wvolatile_register_var,
1347 "optimization may eliminate reads and/or "
1348 "writes to register variables");
1349
1350 /* If the user specified one of the eliminables registers here,
1351 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
1352 confused with that register and be eliminated. This usage is
1353 somewhat suspect... */
1354
1355 SET_DECL_RTL (decl, gen_rtx_raw_REG (mode, reg_number));
1356 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
1357 REG_USERVAR_P (DECL_RTL (decl)) = 1;
1358
1359 if (TREE_STATIC (decl))
1360 {
1361 /* Make this register global, so not usable for anything
1362 else. */
1363 #ifdef ASM_DECLARE_REGISTER_GLOBAL
1364 name = IDENTIFIER_POINTER (DECL_NAME (decl));
1365 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
1366 #endif
1367 nregs = hard_regno_nregs[reg_number][mode];
1368 while (nregs > 0)
1369 globalize_reg (decl, reg_number + --nregs);
1370 }
1371
1372 /* As a register variable, it has no section. */
1373 return;
1374 }
1375 /* Avoid internal errors from invalid register
1376 specifications. */
1377 SET_DECL_ASSEMBLER_NAME (decl, NULL_TREE);
1378 DECL_HARD_REGISTER (decl) = 0;
1379 return;
1380 }
1381 /* Now handle ordinary static variables and functions (in memory).
1382 Also handle vars declared register invalidly. */
1383 else if (name[0] == '*')
1384 {
1385 #ifdef REGISTER_PREFIX
1386 if (strlen (REGISTER_PREFIX) != 0)
1387 {
1388 reg_number = decode_reg_name (name);
1389 if (reg_number >= 0 || reg_number == -3)
1390 error ("register name given for non-register variable %q+D", decl);
1391 }
1392 #endif
1393 }
1394
1395 /* Specifying a section attribute on a variable forces it into a
1396 non-.bss section, and thus it cannot be common. */
1397 /* FIXME: In general this code should not be necessary because
1398 visibility pass is doing the same work. But notice_global_symbol
1399 is called early and it needs to make DECL_RTL to get the name.
1400 we take care of recomputing the DECL_RTL after visibility is changed. */
1401 if (TREE_CODE (decl) == VAR_DECL
1402 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl))
1403 && DECL_SECTION_NAME (decl) != NULL
1404 && DECL_INITIAL (decl) == NULL_TREE
1405 && DECL_COMMON (decl))
1406 DECL_COMMON (decl) = 0;
1407
1408 /* Variables can't be both common and weak. */
1409 if (TREE_CODE (decl) == VAR_DECL && DECL_WEAK (decl))
1410 DECL_COMMON (decl) = 0;
1411
1412 if (use_object_blocks_p () && use_blocks_for_decl_p (decl))
1413 x = create_block_symbol (name, get_block_for_decl (decl), -1);
1414 else
1415 {
1416 enum machine_mode address_mode = Pmode;
1417 if (TREE_TYPE (decl) != error_mark_node)
1418 {
1419 addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1420 address_mode = targetm.addr_space.address_mode (as);
1421 }
1422 x = gen_rtx_SYMBOL_REF (address_mode, name);
1423 }
1424 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
1425 SET_SYMBOL_REF_DECL (x, decl);
1426
1427 x = gen_rtx_MEM (DECL_MODE (decl), x);
1428 if (TREE_CODE (decl) != FUNCTION_DECL)
1429 set_mem_attributes (x, decl, 1);
1430 SET_DECL_RTL (decl, x);
1431
1432 /* Optionally set flags or add text to the name to record information
1433 such as that it is a function name.
1434 If the name is changed, the macro ASM_OUTPUT_LABELREF
1435 will have to know how to strip this information. */
1436 targetm.encode_section_info (decl, DECL_RTL (decl), true);
1437 }
1438
1439 /* Like make_decl_rtl, but inhibit creation of new alias sets when
1440 calling make_decl_rtl. Also, reset DECL_RTL before returning the
1441 rtl. */
1442
1443 rtx
1444 make_decl_rtl_for_debug (tree decl)
1445 {
1446 unsigned int save_aliasing_flag;
1447 rtx rtl;
1448
1449 if (DECL_RTL_SET_P (decl))
1450 return DECL_RTL (decl);
1451
1452 /* Kludge alert! Somewhere down the call chain, make_decl_rtl will
1453 call new_alias_set. If running with -fcompare-debug, sometimes
1454 we do not want to create alias sets that will throw the alias
1455 numbers off in the comparison dumps. So... clearing
1456 flag_strict_aliasing will keep new_alias_set() from creating a
1457 new set. */
1458 save_aliasing_flag = flag_strict_aliasing;
1459 flag_strict_aliasing = 0;
1460
1461 rtl = DECL_RTL (decl);
1462 /* Reset DECL_RTL back, as various parts of the compiler expects
1463 DECL_RTL set meaning it is actually going to be output. */
1464 SET_DECL_RTL (decl, NULL);
1465
1466 flag_strict_aliasing = save_aliasing_flag;
1467 return rtl;
1468 }
1469 \f
1470 /* Output a string of literal assembler code
1471 for an `asm' keyword used between functions. */
1472
1473 void
1474 assemble_asm (tree string)
1475 {
1476 const char *p;
1477 app_enable ();
1478
1479 if (TREE_CODE (string) == ADDR_EXPR)
1480 string = TREE_OPERAND (string, 0);
1481
1482 p = TREE_STRING_POINTER (string);
1483 fprintf (asm_out_file, "%s%s\n", p[0] == '\t' ? "" : "\t", p);
1484 }
1485
1486 /* Write the address of the entity given by SYMBOL to SEC. */
1487 void
1488 assemble_addr_to_section (rtx symbol, section *sec)
1489 {
1490 switch_to_section (sec);
1491 assemble_align (POINTER_SIZE);
1492 assemble_integer (symbol, POINTER_SIZE_UNITS, POINTER_SIZE, 1);
1493 }
1494
1495 /* Return the numbered .ctors.N (if CONSTRUCTOR_P) or .dtors.N (if
1496 not) section for PRIORITY. */
1497 section *
1498 get_cdtor_priority_section (int priority, bool constructor_p)
1499 {
1500 char buf[16];
1501
1502 /* ??? This only works reliably with the GNU linker. */
1503 sprintf (buf, "%s.%.5u",
1504 constructor_p ? ".ctors" : ".dtors",
1505 /* Invert the numbering so the linker puts us in the proper
1506 order; constructors are run from right to left, and the
1507 linker sorts in increasing order. */
1508 MAX_INIT_PRIORITY - priority);
1509 return get_section (buf, SECTION_WRITE, NULL);
1510 }
1511
1512 void
1513 default_named_section_asm_out_destructor (rtx symbol, int priority)
1514 {
1515 section *sec;
1516
1517 if (priority != DEFAULT_INIT_PRIORITY)
1518 sec = get_cdtor_priority_section (priority,
1519 /*constructor_p=*/false);
1520 else
1521 sec = get_section (".dtors", SECTION_WRITE, NULL);
1522
1523 assemble_addr_to_section (symbol, sec);
1524 }
1525
1526 #ifdef DTORS_SECTION_ASM_OP
1527 void
1528 default_dtor_section_asm_out_destructor (rtx symbol,
1529 int priority ATTRIBUTE_UNUSED)
1530 {
1531 assemble_addr_to_section (symbol, dtors_section);
1532 }
1533 #endif
1534
1535 void
1536 default_named_section_asm_out_constructor (rtx symbol, int priority)
1537 {
1538 section *sec;
1539
1540 if (priority != DEFAULT_INIT_PRIORITY)
1541 sec = get_cdtor_priority_section (priority,
1542 /*constructor_p=*/true);
1543 else
1544 sec = get_section (".ctors", SECTION_WRITE, NULL);
1545
1546 assemble_addr_to_section (symbol, sec);
1547 }
1548
1549 #ifdef CTORS_SECTION_ASM_OP
1550 void
1551 default_ctor_section_asm_out_constructor (rtx symbol,
1552 int priority ATTRIBUTE_UNUSED)
1553 {
1554 assemble_addr_to_section (symbol, ctors_section);
1555 }
1556 #endif
1557 \f
1558 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1559 a nonzero value if the constant pool should be output before the
1560 start of the function, or a zero value if the pool should output
1561 after the end of the function. The default is to put it before the
1562 start. */
1563
1564 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1565 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1566 #endif
1567
1568 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1569 to be output to assembler.
1570 Set first_global_object_name and weak_global_object_name as appropriate. */
1571
1572 void
1573 notice_global_symbol (tree decl)
1574 {
1575 const char **type = &first_global_object_name;
1576
1577 if (first_global_object_name
1578 || !TREE_PUBLIC (decl)
1579 || DECL_EXTERNAL (decl)
1580 || !DECL_NAME (decl)
1581 || (TREE_CODE (decl) != FUNCTION_DECL
1582 && (TREE_CODE (decl) != VAR_DECL
1583 || (DECL_COMMON (decl)
1584 && (DECL_INITIAL (decl) == 0
1585 || DECL_INITIAL (decl) == error_mark_node))))
1586 || !MEM_P (DECL_RTL (decl)))
1587 return;
1588
1589 /* We win when global object is found, but it is useful to know about weak
1590 symbol as well so we can produce nicer unique names. */
1591 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl) || flag_shlib)
1592 type = &weak_global_object_name;
1593
1594 if (!*type)
1595 {
1596 const char *p;
1597 const char *name;
1598 rtx decl_rtl = DECL_RTL (decl);
1599
1600 p = targetm.strip_name_encoding (XSTR (XEXP (decl_rtl, 0), 0));
1601 name = ggc_strdup (p);
1602
1603 *type = name;
1604 }
1605 }
1606
1607 /* If not using flag_reorder_blocks_and_partition, decide early whether the
1608 current function goes into the cold section, so that targets can use
1609 current_function_section during RTL expansion. DECL describes the
1610 function. */
1611
1612 void
1613 decide_function_section (tree decl)
1614 {
1615 first_function_block_is_cold = false;
1616
1617 if (flag_reorder_blocks_and_partition)
1618 /* We will decide in assemble_start_function. */
1619 return;
1620
1621 if (DECL_SECTION_NAME (decl))
1622 {
1623 struct cgraph_node *node = cgraph_node::get (current_function_decl);
1624 /* Calls to function_section rely on first_function_block_is_cold
1625 being accurate. */
1626 first_function_block_is_cold = (node
1627 && node->frequency
1628 == NODE_FREQUENCY_UNLIKELY_EXECUTED);
1629 }
1630
1631 in_cold_section_p = first_function_block_is_cold;
1632 }
1633
1634 /* Output assembler code for the constant pool of a function and associated
1635 with defining the name of the function. DECL describes the function.
1636 NAME is the function's name. For the constant pool, we use the current
1637 constant pool data. */
1638
1639 void
1640 assemble_start_function (tree decl, const char *fnname)
1641 {
1642 int align;
1643 char tmp_label[100];
1644 bool hot_label_written = false;
1645
1646 if (flag_reorder_blocks_and_partition)
1647 {
1648 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTB", const_labelno);
1649 crtl->subsections.hot_section_label = ggc_strdup (tmp_label);
1650 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDB", const_labelno);
1651 crtl->subsections.cold_section_label = ggc_strdup (tmp_label);
1652 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTE", const_labelno);
1653 crtl->subsections.hot_section_end_label = ggc_strdup (tmp_label);
1654 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDE", const_labelno);
1655 crtl->subsections.cold_section_end_label = ggc_strdup (tmp_label);
1656 const_labelno++;
1657 }
1658 else
1659 {
1660 crtl->subsections.hot_section_label = NULL;
1661 crtl->subsections.cold_section_label = NULL;
1662 crtl->subsections.hot_section_end_label = NULL;
1663 crtl->subsections.cold_section_end_label = NULL;
1664 }
1665
1666 /* The following code does not need preprocessing in the assembler. */
1667
1668 app_disable ();
1669
1670 if (CONSTANT_POOL_BEFORE_FUNCTION)
1671 output_constant_pool (fnname, decl);
1672
1673 /* Make sure the not and cold text (code) sections are properly
1674 aligned. This is necessary here in the case where the function
1675 has both hot and cold sections, because we don't want to re-set
1676 the alignment when the section switch happens mid-function. */
1677
1678 if (flag_reorder_blocks_and_partition)
1679 {
1680 first_function_block_is_cold = false;
1681
1682 switch_to_section (unlikely_text_section ());
1683 assemble_align (DECL_ALIGN (decl));
1684 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_label);
1685
1686 /* When the function starts with a cold section, we need to explicitly
1687 align the hot section and write out the hot section label.
1688 But if the current function is a thunk, we do not have a CFG. */
1689 if (!cfun->is_thunk
1690 && BB_PARTITION (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) == BB_COLD_PARTITION)
1691 {
1692 switch_to_section (text_section);
1693 assemble_align (DECL_ALIGN (decl));
1694 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1695 hot_label_written = true;
1696 first_function_block_is_cold = true;
1697 }
1698 in_cold_section_p = first_function_block_is_cold;
1699 }
1700
1701
1702 /* Switch to the correct text section for the start of the function. */
1703
1704 switch_to_section (function_section (decl));
1705 if (flag_reorder_blocks_and_partition
1706 && !hot_label_written)
1707 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1708
1709 /* Tell assembler to move to target machine's alignment for functions. */
1710 align = floor_log2 (DECL_ALIGN (decl) / BITS_PER_UNIT);
1711 if (align > 0)
1712 {
1713 ASM_OUTPUT_ALIGN (asm_out_file, align);
1714 }
1715
1716 /* Handle a user-specified function alignment.
1717 Note that we still need to align to DECL_ALIGN, as above,
1718 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1719 if (! DECL_USER_ALIGN (decl)
1720 && align_functions_log > align
1721 && optimize_function_for_speed_p (cfun))
1722 {
1723 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1724 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1725 align_functions_log, align_functions - 1);
1726 #else
1727 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1728 #endif
1729 }
1730
1731 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1732 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1733 #endif
1734
1735 if (!DECL_IGNORED_P (decl))
1736 (*debug_hooks->begin_function) (decl);
1737
1738 /* Make function name accessible from other files, if appropriate. */
1739
1740 if (TREE_PUBLIC (decl))
1741 {
1742 notice_global_symbol (decl);
1743
1744 globalize_decl (decl);
1745
1746 maybe_assemble_visibility (decl);
1747 }
1748
1749 if (DECL_PRESERVE_P (decl))
1750 targetm.asm_out.mark_decl_preserved (fnname);
1751
1752 /* Do any machine/system dependent processing of the function name. */
1753 #ifdef ASM_DECLARE_FUNCTION_NAME
1754 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1755 #else
1756 /* Standard thing is just output label for the function. */
1757 ASM_OUTPUT_FUNCTION_LABEL (asm_out_file, fnname, current_function_decl);
1758 #endif /* ASM_DECLARE_FUNCTION_NAME */
1759
1760 if (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (decl)))
1761 saw_no_split_stack = true;
1762 }
1763
1764 /* Output assembler code associated with defining the size of the
1765 function. DECL describes the function. NAME is the function's name. */
1766
1767 void
1768 assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED)
1769 {
1770 #ifdef ASM_DECLARE_FUNCTION_SIZE
1771 /* We could have switched section in the middle of the function. */
1772 if (flag_reorder_blocks_and_partition)
1773 switch_to_section (function_section (decl));
1774 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1775 #endif
1776 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1777 {
1778 output_constant_pool (fnname, decl);
1779 switch_to_section (function_section (decl)); /* need to switch back */
1780 }
1781 /* Output labels for end of hot/cold text sections (to be used by
1782 debug info.) */
1783 if (flag_reorder_blocks_and_partition)
1784 {
1785 section *save_text_section;
1786
1787 save_text_section = in_section;
1788 switch_to_section (unlikely_text_section ());
1789 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label);
1790 if (first_function_block_is_cold)
1791 switch_to_section (text_section);
1792 else
1793 switch_to_section (function_section (decl));
1794 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label);
1795 switch_to_section (save_text_section);
1796 }
1797 }
1798 \f
1799 /* Assemble code to leave SIZE bytes of zeros. */
1800
1801 void
1802 assemble_zeros (unsigned HOST_WIDE_INT size)
1803 {
1804 /* Do no output if -fsyntax-only. */
1805 if (flag_syntax_only)
1806 return;
1807
1808 #ifdef ASM_NO_SKIP_IN_TEXT
1809 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1810 so we must output 0s explicitly in the text section. */
1811 if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0)
1812 {
1813 unsigned HOST_WIDE_INT i;
1814 for (i = 0; i < size; i++)
1815 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1816 }
1817 else
1818 #endif
1819 if (size > 0)
1820 ASM_OUTPUT_SKIP (asm_out_file, size);
1821 }
1822
1823 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1824
1825 void
1826 assemble_align (int align)
1827 {
1828 if (align > BITS_PER_UNIT)
1829 {
1830 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1831 }
1832 }
1833
1834 /* Assemble a string constant with the specified C string as contents. */
1835
1836 void
1837 assemble_string (const char *p, int size)
1838 {
1839 int pos = 0;
1840 int maximum = 2000;
1841
1842 /* If the string is very long, split it up. */
1843
1844 while (pos < size)
1845 {
1846 int thissize = size - pos;
1847 if (thissize > maximum)
1848 thissize = maximum;
1849
1850 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1851
1852 pos += thissize;
1853 p += thissize;
1854 }
1855 }
1856
1857 \f
1858 /* A noswitch_section_callback for lcomm_section. */
1859
1860 static bool
1861 emit_local (tree decl ATTRIBUTE_UNUSED,
1862 const char *name ATTRIBUTE_UNUSED,
1863 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1864 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1865 {
1866 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1867 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name,
1868 size, DECL_ALIGN (decl));
1869 return true;
1870 #elif defined ASM_OUTPUT_ALIGNED_LOCAL
1871 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, DECL_ALIGN (decl));
1872 return true;
1873 #else
1874 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1875 return false;
1876 #endif
1877 }
1878
1879 /* A noswitch_section_callback for bss_noswitch_section. */
1880
1881 #if defined ASM_OUTPUT_ALIGNED_BSS
1882 static bool
1883 emit_bss (tree decl ATTRIBUTE_UNUSED,
1884 const char *name ATTRIBUTE_UNUSED,
1885 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1886 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1887 {
1888 #if defined ASM_OUTPUT_ALIGNED_BSS
1889 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size,
1890 get_variable_align (decl));
1891 return true;
1892 #endif
1893 }
1894 #endif
1895
1896 /* A noswitch_section_callback for comm_section. */
1897
1898 static bool
1899 emit_common (tree decl ATTRIBUTE_UNUSED,
1900 const char *name ATTRIBUTE_UNUSED,
1901 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1902 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1903 {
1904 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1905 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name,
1906 size, get_variable_align (decl));
1907 return true;
1908 #elif defined ASM_OUTPUT_ALIGNED_COMMON
1909 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size,
1910 get_variable_align (decl));
1911 return true;
1912 #else
1913 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
1914 return false;
1915 #endif
1916 }
1917
1918 /* A noswitch_section_callback for tls_comm_section. */
1919
1920 static bool
1921 emit_tls_common (tree decl ATTRIBUTE_UNUSED,
1922 const char *name ATTRIBUTE_UNUSED,
1923 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1924 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1925 {
1926 #ifdef ASM_OUTPUT_TLS_COMMON
1927 ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size);
1928 return true;
1929 #else
1930 sorry ("thread-local COMMON data not implemented");
1931 return true;
1932 #endif
1933 }
1934
1935 /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT.
1936 NAME is the name of DECL's SYMBOL_REF. */
1937
1938 static void
1939 assemble_noswitch_variable (tree decl, const char *name, section *sect,
1940 unsigned int align)
1941 {
1942 unsigned HOST_WIDE_INT size, rounded;
1943
1944 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
1945 rounded = size;
1946
1947 if ((flag_sanitize & SANITIZE_ADDRESS) && asan_protect_global (decl))
1948 size += asan_red_zone_size (size);
1949
1950 /* Don't allocate zero bytes of common,
1951 since that means "undefined external" in the linker. */
1952 if (size == 0)
1953 rounded = 1;
1954
1955 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1956 so that each uninitialized object starts on such a boundary. */
1957 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
1958 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1959 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1960
1961 if (!sect->noswitch.callback (decl, name, size, rounded)
1962 && (unsigned HOST_WIDE_INT) (align / BITS_PER_UNIT) > rounded)
1963 error ("requested alignment for %q+D is greater than "
1964 "implemented alignment of %wu", decl, rounded);
1965 }
1966
1967 /* A subroutine of assemble_variable. Output the label and contents of
1968 DECL, whose address is a SYMBOL_REF with name NAME. DONT_OUTPUT_DATA
1969 is as for assemble_variable. */
1970
1971 static void
1972 assemble_variable_contents (tree decl, const char *name,
1973 bool dont_output_data)
1974 {
1975 /* Do any machine/system dependent processing of the object. */
1976 #ifdef ASM_DECLARE_OBJECT_NAME
1977 last_assemble_variable_decl = decl;
1978 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
1979 #else
1980 /* Standard thing is just output label for the object. */
1981 ASM_OUTPUT_LABEL (asm_out_file, name);
1982 #endif /* ASM_DECLARE_OBJECT_NAME */
1983
1984 if (!dont_output_data)
1985 {
1986 /* Caller is supposed to use varpool_get_constructor when it wants
1987 to output the body. */
1988 gcc_assert (!in_lto_p || DECL_INITIAL (decl) != error_mark_node);
1989 if (DECL_INITIAL (decl)
1990 && DECL_INITIAL (decl) != error_mark_node
1991 && !initializer_zerop (DECL_INITIAL (decl)))
1992 /* Output the actual data. */
1993 output_constant (DECL_INITIAL (decl),
1994 tree_to_uhwi (DECL_SIZE_UNIT (decl)),
1995 get_variable_align (decl));
1996 else
1997 /* Leave space for it. */
1998 assemble_zeros (tree_to_uhwi (DECL_SIZE_UNIT (decl)));
1999 }
2000 }
2001
2002 /* Assemble everything that is needed for a variable or function declaration.
2003 Not used for automatic variables, and not used for function definitions.
2004 Should not be called for variables of incomplete structure type.
2005
2006 TOP_LEVEL is nonzero if this variable has file scope.
2007 AT_END is nonzero if this is the special handling, at end of compilation,
2008 to define things that have had only tentative definitions.
2009 DONT_OUTPUT_DATA if nonzero means don't actually output the
2010 initial value (that will be done by the caller). */
2011
2012 void
2013 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
2014 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
2015 {
2016 const char *name;
2017 rtx decl_rtl, symbol;
2018 section *sect;
2019 unsigned int align;
2020 bool asan_protected = false;
2021
2022 /* This function is supposed to handle VARIABLES. Ensure we have one. */
2023 gcc_assert (TREE_CODE (decl) == VAR_DECL);
2024
2025 /* Emulated TLS had better not get this far. */
2026 gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl));
2027
2028 last_assemble_variable_decl = 0;
2029
2030 /* Normally no need to say anything here for external references,
2031 since assemble_external is called by the language-specific code
2032 when a declaration is first seen. */
2033
2034 if (DECL_EXTERNAL (decl))
2035 return;
2036
2037 /* Do nothing for global register variables. */
2038 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
2039 {
2040 TREE_ASM_WRITTEN (decl) = 1;
2041 return;
2042 }
2043
2044 /* If type was incomplete when the variable was declared,
2045 see if it is complete now. */
2046
2047 if (DECL_SIZE (decl) == 0)
2048 layout_decl (decl, 0);
2049
2050 /* Still incomplete => don't allocate it; treat the tentative defn
2051 (which is what it must have been) as an `extern' reference. */
2052
2053 if (!dont_output_data && DECL_SIZE (decl) == 0)
2054 {
2055 error ("storage size of %q+D isn%'t known", decl);
2056 TREE_ASM_WRITTEN (decl) = 1;
2057 return;
2058 }
2059
2060 /* The first declaration of a variable that comes through this function
2061 decides whether it is global (in C, has external linkage)
2062 or local (in C, has internal linkage). So do nothing more
2063 if this function has already run. */
2064
2065 if (TREE_ASM_WRITTEN (decl))
2066 return;
2067
2068 /* Make sure targetm.encode_section_info is invoked before we set
2069 ASM_WRITTEN. */
2070 decl_rtl = DECL_RTL (decl);
2071
2072 TREE_ASM_WRITTEN (decl) = 1;
2073
2074 /* Do no output if -fsyntax-only. */
2075 if (flag_syntax_only)
2076 return;
2077
2078 if (! dont_output_data
2079 && ! valid_constant_size_p (DECL_SIZE_UNIT (decl)))
2080 {
2081 error ("size of variable %q+D is too large", decl);
2082 return;
2083 }
2084
2085 gcc_assert (MEM_P (decl_rtl));
2086 gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF);
2087 symbol = XEXP (decl_rtl, 0);
2088
2089 /* If this symbol belongs to the tree constant pool, output the constant
2090 if it hasn't already been written. */
2091 if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
2092 {
2093 tree decl = SYMBOL_REF_DECL (symbol);
2094 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
2095 output_constant_def_contents (symbol);
2096 return;
2097 }
2098
2099 app_disable ();
2100
2101 name = XSTR (symbol, 0);
2102 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
2103 notice_global_symbol (decl);
2104
2105 /* Compute the alignment of this data. */
2106
2107 align_variable (decl, dont_output_data);
2108
2109 if ((flag_sanitize & SANITIZE_ADDRESS)
2110 && asan_protect_global (decl))
2111 {
2112 asan_protected = true;
2113 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
2114 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
2115 }
2116
2117 set_mem_align (decl_rtl, DECL_ALIGN (decl));
2118
2119 align = get_variable_align (decl);
2120
2121 if (TREE_PUBLIC (decl))
2122 maybe_assemble_visibility (decl);
2123
2124 if (DECL_PRESERVE_P (decl))
2125 targetm.asm_out.mark_decl_preserved (name);
2126
2127 /* First make the assembler name(s) global if appropriate. */
2128 sect = get_variable_section (decl, false);
2129 if (TREE_PUBLIC (decl)
2130 && (sect->common.flags & SECTION_COMMON) == 0)
2131 globalize_decl (decl);
2132
2133 /* Output any data that we will need to use the address of. */
2134 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
2135 output_addressed_constants (DECL_INITIAL (decl));
2136
2137 /* dbxout.c needs to know this. */
2138 if (sect && (sect->common.flags & SECTION_CODE) != 0)
2139 DECL_IN_TEXT_SECTION (decl) = 1;
2140
2141 /* If the decl is part of an object_block, make sure that the decl
2142 has been positioned within its block, but do not write out its
2143 definition yet. output_object_blocks will do that later. */
2144 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
2145 {
2146 gcc_assert (!dont_output_data);
2147 place_block_symbol (symbol);
2148 }
2149 else if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
2150 assemble_noswitch_variable (decl, name, sect, align);
2151 else
2152 {
2153 /* The following bit of code ensures that vtable_map
2154 variables are not only in the comdat section, but that
2155 each variable has its own unique comdat name. If this
2156 code is removed, the variables end up in the same section
2157 with a single comdat name.
2158
2159 FIXME: resolve_unique_section needs to deal better with
2160 decls with both DECL_SECTION_NAME and DECL_ONE_ONLY. Once
2161 that is fixed, this if-else statement can be replaced with
2162 a single call to "switch_to_section (sect)". */
2163 if (sect->named.name
2164 && (strcmp (sect->named.name, ".vtable_map_vars") == 0))
2165 {
2166 #if defined (OBJECT_FORMAT_ELF)
2167 targetm.asm_out.named_section (sect->named.name,
2168 sect->named.common.flags
2169 | SECTION_LINKONCE,
2170 DECL_NAME (decl));
2171 in_section = sect;
2172 #else
2173 switch_to_section (sect);
2174 #endif
2175 }
2176 else
2177 switch_to_section (sect);
2178 if (align > BITS_PER_UNIT)
2179 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2180 assemble_variable_contents (decl, name, dont_output_data);
2181 if (asan_protected)
2182 {
2183 unsigned HOST_WIDE_INT int size
2184 = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2185 assemble_zeros (asan_red_zone_size (size));
2186 }
2187 }
2188 }
2189
2190
2191 /* Given a function declaration (FN_DECL), this function assembles the
2192 function into the .preinit_array section. */
2193
2194 void
2195 assemble_vtv_preinit_initializer (tree fn_decl)
2196 {
2197 section *sect;
2198 unsigned flags = SECTION_WRITE;
2199 rtx symbol = XEXP (DECL_RTL (fn_decl), 0);
2200
2201 flags |= SECTION_NOTYPE;
2202 sect = get_section (".preinit_array", flags, fn_decl);
2203 switch_to_section (sect);
2204 assemble_addr_to_section (symbol, sect);
2205 }
2206
2207 /* Return 1 if type TYPE contains any pointers. */
2208
2209 static int
2210 contains_pointers_p (tree type)
2211 {
2212 switch (TREE_CODE (type))
2213 {
2214 case POINTER_TYPE:
2215 case REFERENCE_TYPE:
2216 /* I'm not sure whether OFFSET_TYPE needs this treatment,
2217 so I'll play safe and return 1. */
2218 case OFFSET_TYPE:
2219 return 1;
2220
2221 case RECORD_TYPE:
2222 case UNION_TYPE:
2223 case QUAL_UNION_TYPE:
2224 {
2225 tree fields;
2226 /* For a type that has fields, see if the fields have pointers. */
2227 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2228 if (TREE_CODE (fields) == FIELD_DECL
2229 && contains_pointers_p (TREE_TYPE (fields)))
2230 return 1;
2231 return 0;
2232 }
2233
2234 case ARRAY_TYPE:
2235 /* An array type contains pointers if its element type does. */
2236 return contains_pointers_p (TREE_TYPE (type));
2237
2238 default:
2239 return 0;
2240 }
2241 }
2242
2243 /* We delay assemble_external processing until
2244 the compilation unit is finalized. This is the best we can do for
2245 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2246 it all the way to final. See PR 17982 for further discussion. */
2247 static GTY(()) tree pending_assemble_externals;
2248
2249 #ifdef ASM_OUTPUT_EXTERNAL
2250 /* Some targets delay some output to final using TARGET_ASM_FILE_END.
2251 As a result, assemble_external can be called after the list of externals
2252 is processed and the pointer set destroyed. */
2253 static bool pending_assemble_externals_processed;
2254
2255 /* Avoid O(external_decls**2) lookups in the pending_assemble_externals
2256 TREE_LIST in assemble_external. */
2257 static hash_set<tree> *pending_assemble_externals_set;
2258
2259 /* True if DECL is a function decl for which no out-of-line copy exists.
2260 It is assumed that DECL's assembler name has been set. */
2261
2262 static bool
2263 incorporeal_function_p (tree decl)
2264 {
2265 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
2266 {
2267 const char *name;
2268
2269 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2270 && (DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA
2271 || DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA_WITH_ALIGN))
2272 return true;
2273
2274 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2275 /* Atomic or sync builtins which have survived this far will be
2276 resolved externally and therefore are not incorporeal. */
2277 if (strncmp (name, "__builtin_", 10) == 0)
2278 return true;
2279 }
2280 return false;
2281 }
2282
2283 /* Actually do the tests to determine if this is necessary, and invoke
2284 ASM_OUTPUT_EXTERNAL. */
2285 static void
2286 assemble_external_real (tree decl)
2287 {
2288 rtx rtl = DECL_RTL (decl);
2289
2290 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2291 && !SYMBOL_REF_USED (XEXP (rtl, 0))
2292 && !incorporeal_function_p (decl))
2293 {
2294 /* Some systems do require some output. */
2295 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2296 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2297 }
2298 }
2299 #endif
2300
2301 void
2302 process_pending_assemble_externals (void)
2303 {
2304 #ifdef ASM_OUTPUT_EXTERNAL
2305 tree list;
2306 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2307 assemble_external_real (TREE_VALUE (list));
2308
2309 pending_assemble_externals = 0;
2310 pending_assemble_externals_processed = true;
2311 delete pending_assemble_externals_set;
2312 #endif
2313 }
2314
2315 /* This TREE_LIST contains any weak symbol declarations waiting
2316 to be emitted. */
2317 static GTY(()) tree weak_decls;
2318
2319 /* Output something to declare an external symbol to the assembler,
2320 and qualifiers such as weakness. (Most assemblers don't need
2321 extern declaration, so we normally output nothing.) Do nothing if
2322 DECL is not external. */
2323
2324 void
2325 assemble_external (tree decl ATTRIBUTE_UNUSED)
2326 {
2327 /* Make sure that the ASM_OUT_FILE is open.
2328 If it's not, we should not be calling this function. */
2329 gcc_assert (asm_out_file);
2330
2331 /* In a perfect world, the following condition would be true.
2332 Sadly, the Java and Go front ends emit assembly *from the front end*,
2333 bypassing the call graph. See PR52739. Fix before GCC 4.8. */
2334 #if 0
2335 /* This function should only be called if we are expanding, or have
2336 expanded, to RTL.
2337 Ideally, only final.c would be calling this function, but it is
2338 not clear whether that would break things somehow. See PR 17982
2339 for further discussion. */
2340 gcc_assert (state == EXPANSION
2341 || state == FINISHED);
2342 #endif
2343
2344 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2345 return;
2346
2347 /* We want to output annotation for weak and external symbols at
2348 very last to check if they are references or not. */
2349
2350 if (TARGET_SUPPORTS_WEAK
2351 && DECL_WEAK (decl)
2352 /* TREE_STATIC is a weird and abused creature which is not
2353 generally the right test for whether an entity has been
2354 locally emitted, inlined or otherwise not-really-extern, but
2355 for declarations that can be weak, it happens to be
2356 match. */
2357 && !TREE_STATIC (decl)
2358 && lookup_attribute ("weak", DECL_ATTRIBUTES (decl))
2359 && value_member (decl, weak_decls) == NULL_TREE)
2360 weak_decls = tree_cons (NULL, decl, weak_decls);
2361
2362 #ifdef ASM_OUTPUT_EXTERNAL
2363 if (pending_assemble_externals_processed)
2364 {
2365 assemble_external_real (decl);
2366 return;
2367 }
2368
2369 if (! pending_assemble_externals_set->add (decl))
2370 pending_assemble_externals = tree_cons (NULL, decl,
2371 pending_assemble_externals);
2372 #endif
2373 }
2374
2375 /* Similar, for calling a library function FUN. */
2376
2377 void
2378 assemble_external_libcall (rtx fun)
2379 {
2380 /* Declare library function name external when first used, if nec. */
2381 if (! SYMBOL_REF_USED (fun))
2382 {
2383 SYMBOL_REF_USED (fun) = 1;
2384 targetm.asm_out.external_libcall (fun);
2385 }
2386 }
2387
2388 /* Assemble a label named NAME. */
2389
2390 void
2391 assemble_label (FILE *file, const char *name)
2392 {
2393 ASM_OUTPUT_LABEL (file, name);
2394 }
2395
2396 /* Set the symbol_referenced flag for ID. */
2397 void
2398 mark_referenced (tree id)
2399 {
2400 TREE_SYMBOL_REFERENCED (id) = 1;
2401 }
2402
2403 /* Set the symbol_referenced flag for DECL and notify callgraph. */
2404 void
2405 mark_decl_referenced (tree decl)
2406 {
2407 if (TREE_CODE (decl) == FUNCTION_DECL)
2408 {
2409 /* Extern inline functions don't become needed when referenced.
2410 If we know a method will be emitted in other TU and no new
2411 functions can be marked reachable, just use the external
2412 definition. */
2413 struct cgraph_node *node = cgraph_node::get_create (decl);
2414 if (!DECL_EXTERNAL (decl)
2415 && !node->definition)
2416 node->mark_force_output ();
2417 }
2418 else if (TREE_CODE (decl) == VAR_DECL)
2419 {
2420 varpool_node *node = varpool_node::get_create (decl);
2421 /* C++ frontend use mark_decl_references to force COMDAT variables
2422 to be output that might appear dead otherwise. */
2423 node->force_output = true;
2424 }
2425 /* else do nothing - we can get various sorts of CST nodes here,
2426 which do not need to be marked. */
2427 }
2428
2429
2430 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS
2431 until we find an identifier that is not itself a transparent alias.
2432 Modify the alias passed to it by reference (and all aliases on the
2433 way to the ultimate target), such that they do not have to be
2434 followed again, and return the ultimate target of the alias
2435 chain. */
2436
2437 static inline tree
2438 ultimate_transparent_alias_target (tree *alias)
2439 {
2440 tree target = *alias;
2441
2442 if (IDENTIFIER_TRANSPARENT_ALIAS (target))
2443 {
2444 gcc_assert (TREE_CHAIN (target));
2445 target = ultimate_transparent_alias_target (&TREE_CHAIN (target));
2446 gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target)
2447 && ! TREE_CHAIN (target));
2448 *alias = target;
2449 }
2450
2451 return target;
2452 }
2453
2454 /* Output to FILE (an assembly file) a reference to NAME. If NAME
2455 starts with a *, the rest of NAME is output verbatim. Otherwise
2456 NAME is transformed in a target-specific way (usually by the
2457 addition of an underscore). */
2458
2459 void
2460 assemble_name_raw (FILE *file, const char *name)
2461 {
2462 if (name[0] == '*')
2463 fputs (&name[1], file);
2464 else
2465 ASM_OUTPUT_LABELREF (file, name);
2466 }
2467
2468 /* Like assemble_name_raw, but should be used when NAME might refer to
2469 an entity that is also represented as a tree (like a function or
2470 variable). If NAME does refer to such an entity, that entity will
2471 be marked as referenced. */
2472
2473 void
2474 assemble_name (FILE *file, const char *name)
2475 {
2476 const char *real_name;
2477 tree id;
2478
2479 real_name = targetm.strip_name_encoding (name);
2480
2481 id = maybe_get_identifier (real_name);
2482 if (id)
2483 {
2484 tree id_orig = id;
2485
2486 mark_referenced (id);
2487 ultimate_transparent_alias_target (&id);
2488 if (id != id_orig)
2489 name = IDENTIFIER_POINTER (id);
2490 gcc_assert (! TREE_CHAIN (id));
2491 }
2492
2493 assemble_name_raw (file, name);
2494 }
2495
2496 /* Allocate SIZE bytes writable static space with a gensym name
2497 and return an RTX to refer to its address. */
2498
2499 rtx
2500 assemble_static_space (unsigned HOST_WIDE_INT size)
2501 {
2502 char name[12];
2503 const char *namestring;
2504 rtx x;
2505
2506 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2507 ++const_labelno;
2508 namestring = ggc_strdup (name);
2509
2510 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2511 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2512
2513 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2514 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2515 BIGGEST_ALIGNMENT);
2516 #else
2517 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2518 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2519 #else
2520 {
2521 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2522 so that each uninitialized object starts on such a boundary. */
2523 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2524 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2525 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2526 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2527 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2528 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2529 }
2530 #endif
2531 #endif
2532 return x;
2533 }
2534
2535 /* Assemble the static constant template for function entry trampolines.
2536 This is done at most once per compilation.
2537 Returns an RTX for the address of the template. */
2538
2539 static GTY(()) rtx initial_trampoline;
2540
2541 rtx
2542 assemble_trampoline_template (void)
2543 {
2544 char label[256];
2545 const char *name;
2546 int align;
2547 rtx symbol;
2548
2549 gcc_assert (targetm.asm_out.trampoline_template != NULL);
2550
2551 if (initial_trampoline)
2552 return initial_trampoline;
2553
2554 /* By default, put trampoline templates in read-only data section. */
2555
2556 #ifdef TRAMPOLINE_SECTION
2557 switch_to_section (TRAMPOLINE_SECTION);
2558 #else
2559 switch_to_section (readonly_data_section);
2560 #endif
2561
2562 /* Write the assembler code to define one. */
2563 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2564 if (align > 0)
2565 ASM_OUTPUT_ALIGN (asm_out_file, align);
2566
2567 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2568 targetm.asm_out.trampoline_template (asm_out_file);
2569
2570 /* Record the rtl to refer to it. */
2571 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2572 name = ggc_strdup (label);
2573 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2574 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2575
2576 initial_trampoline = gen_const_mem (BLKmode, symbol);
2577 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2578 set_mem_size (initial_trampoline, TRAMPOLINE_SIZE);
2579
2580 return initial_trampoline;
2581 }
2582 \f
2583 /* A and B are either alignments or offsets. Return the minimum alignment
2584 that may be assumed after adding the two together. */
2585
2586 static inline unsigned
2587 min_align (unsigned int a, unsigned int b)
2588 {
2589 return (a | b) & -(a | b);
2590 }
2591
2592 /* Return the assembler directive for creating a given kind of integer
2593 object. SIZE is the number of bytes in the object and ALIGNED_P
2594 indicates whether it is known to be aligned. Return NULL if the
2595 assembly dialect has no such directive.
2596
2597 The returned string should be printed at the start of a new line and
2598 be followed immediately by the object's initial value. */
2599
2600 const char *
2601 integer_asm_op (int size, int aligned_p)
2602 {
2603 struct asm_int_op *ops;
2604
2605 if (aligned_p)
2606 ops = &targetm.asm_out.aligned_op;
2607 else
2608 ops = &targetm.asm_out.unaligned_op;
2609
2610 switch (size)
2611 {
2612 case 1:
2613 return targetm.asm_out.byte_op;
2614 case 2:
2615 return ops->hi;
2616 case 4:
2617 return ops->si;
2618 case 8:
2619 return ops->di;
2620 case 16:
2621 return ops->ti;
2622 default:
2623 return NULL;
2624 }
2625 }
2626
2627 /* Use directive OP to assemble an integer object X. Print OP at the
2628 start of the line, followed immediately by the value of X. */
2629
2630 void
2631 assemble_integer_with_op (const char *op, rtx x)
2632 {
2633 fputs (op, asm_out_file);
2634 output_addr_const (asm_out_file, x);
2635 fputc ('\n', asm_out_file);
2636 }
2637
2638 /* The default implementation of the asm_out.integer target hook. */
2639
2640 bool
2641 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2642 unsigned int size ATTRIBUTE_UNUSED,
2643 int aligned_p ATTRIBUTE_UNUSED)
2644 {
2645 const char *op = integer_asm_op (size, aligned_p);
2646 /* Avoid GAS bugs for large values. Specifically negative values whose
2647 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2648 if (size > UNITS_PER_WORD && size > POINTER_SIZE_UNITS)
2649 return false;
2650 return op && (assemble_integer_with_op (op, x), true);
2651 }
2652
2653 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2654 the alignment of the integer in bits. Return 1 if we were able to output
2655 the constant, otherwise 0. We must be able to output the constant,
2656 if FORCE is nonzero. */
2657
2658 bool
2659 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2660 {
2661 int aligned_p;
2662
2663 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2664
2665 /* See if the target hook can handle this kind of object. */
2666 if (targetm.asm_out.integer (x, size, aligned_p))
2667 return true;
2668
2669 /* If the object is a multi-byte one, try splitting it up. Split
2670 it into words it if is multi-word, otherwise split it into bytes. */
2671 if (size > 1)
2672 {
2673 enum machine_mode omode, imode;
2674 unsigned int subalign;
2675 unsigned int subsize, i;
2676 enum mode_class mclass;
2677
2678 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2679 subalign = MIN (align, subsize * BITS_PER_UNIT);
2680 if (GET_CODE (x) == CONST_FIXED)
2681 mclass = GET_MODE_CLASS (GET_MODE (x));
2682 else
2683 mclass = MODE_INT;
2684
2685 omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0);
2686 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0);
2687
2688 for (i = 0; i < size; i += subsize)
2689 {
2690 rtx partial = simplify_subreg (omode, x, imode, i);
2691 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2692 break;
2693 }
2694 if (i == size)
2695 return true;
2696
2697 /* If we've printed some of it, but not all of it, there's no going
2698 back now. */
2699 gcc_assert (!i);
2700 }
2701
2702 gcc_assert (!force);
2703
2704 return false;
2705 }
2706 \f
2707 void
2708 assemble_real (REAL_VALUE_TYPE d, enum machine_mode mode, unsigned int align)
2709 {
2710 long data[4] = {0, 0, 0, 0};
2711 int i;
2712 int bitsize, nelts, nunits, units_per;
2713
2714 /* This is hairy. We have a quantity of known size. real_to_target
2715 will put it into an array of *host* longs, 32 bits per element
2716 (even if long is more than 32 bits). We need to determine the
2717 number of array elements that are occupied (nelts) and the number
2718 of *target* min-addressable units that will be occupied in the
2719 object file (nunits). We cannot assume that 32 divides the
2720 mode's bitsize (size * BITS_PER_UNIT) evenly.
2721
2722 size * BITS_PER_UNIT is used here to make sure that padding bits
2723 (which might appear at either end of the value; real_to_target
2724 will include the padding bits in its output array) are included. */
2725
2726 nunits = GET_MODE_SIZE (mode);
2727 bitsize = nunits * BITS_PER_UNIT;
2728 nelts = CEIL (bitsize, 32);
2729 units_per = 32 / BITS_PER_UNIT;
2730
2731 real_to_target (data, &d, mode);
2732
2733 /* Put out the first word with the specified alignment. */
2734 assemble_integer (GEN_INT (data[0]), MIN (nunits, units_per), align, 1);
2735 nunits -= units_per;
2736
2737 /* Subsequent words need only 32-bit alignment. */
2738 align = min_align (align, 32);
2739
2740 for (i = 1; i < nelts; i++)
2741 {
2742 assemble_integer (GEN_INT (data[i]), MIN (nunits, units_per), align, 1);
2743 nunits -= units_per;
2744 }
2745 }
2746 \f
2747 /* Given an expression EXP with a constant value,
2748 reduce it to the sum of an assembler symbol and an integer.
2749 Store them both in the structure *VALUE.
2750 EXP must be reducible. */
2751
2752 struct addr_const {
2753 rtx base;
2754 HOST_WIDE_INT offset;
2755 };
2756
2757 static void
2758 decode_addr_const (tree exp, struct addr_const *value)
2759 {
2760 tree target = TREE_OPERAND (exp, 0);
2761 int offset = 0;
2762 rtx x;
2763
2764 while (1)
2765 {
2766 if (TREE_CODE (target) == COMPONENT_REF
2767 && tree_fits_shwi_p (byte_position (TREE_OPERAND (target, 1))))
2768 {
2769 offset += int_byte_position (TREE_OPERAND (target, 1));
2770 target = TREE_OPERAND (target, 0);
2771 }
2772 else if (TREE_CODE (target) == ARRAY_REF
2773 || TREE_CODE (target) == ARRAY_RANGE_REF)
2774 {
2775 offset += (tree_to_uhwi (TYPE_SIZE_UNIT (TREE_TYPE (target)))
2776 * tree_to_shwi (TREE_OPERAND (target, 1)));
2777 target = TREE_OPERAND (target, 0);
2778 }
2779 else if (TREE_CODE (target) == MEM_REF
2780 && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR)
2781 {
2782 offset += mem_ref_offset (target).to_short_addr ();
2783 target = TREE_OPERAND (TREE_OPERAND (target, 0), 0);
2784 }
2785 else if (TREE_CODE (target) == INDIRECT_REF
2786 && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR
2787 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0))
2788 == ADDR_EXPR)
2789 target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0);
2790 else
2791 break;
2792 }
2793
2794 switch (TREE_CODE (target))
2795 {
2796 case VAR_DECL:
2797 case FUNCTION_DECL:
2798 x = DECL_RTL (target);
2799 break;
2800
2801 case LABEL_DECL:
2802 x = gen_rtx_MEM (FUNCTION_MODE,
2803 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2804 break;
2805
2806 case REAL_CST:
2807 case FIXED_CST:
2808 case STRING_CST:
2809 case COMPLEX_CST:
2810 case CONSTRUCTOR:
2811 case INTEGER_CST:
2812 x = output_constant_def (target, 1);
2813 break;
2814
2815 default:
2816 gcc_unreachable ();
2817 }
2818
2819 gcc_assert (MEM_P (x));
2820 x = XEXP (x, 0);
2821
2822 value->base = x;
2823 value->offset = offset;
2824 }
2825 \f
2826
2827 static GTY((param_is (struct constant_descriptor_tree)))
2828 htab_t const_desc_htab;
2829
2830 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2831
2832 /* Constant pool accessor function. */
2833
2834 htab_t
2835 constant_pool_htab (void)
2836 {
2837 return const_desc_htab;
2838 }
2839
2840 /* Compute a hash code for a constant expression. */
2841
2842 static hashval_t
2843 const_desc_hash (const void *ptr)
2844 {
2845 return ((const struct constant_descriptor_tree *)ptr)->hash;
2846 }
2847
2848 static hashval_t
2849 const_hash_1 (const tree exp)
2850 {
2851 const char *p;
2852 hashval_t hi;
2853 int len, i;
2854 enum tree_code code = TREE_CODE (exp);
2855
2856 /* Either set P and LEN to the address and len of something to hash and
2857 exit the switch or return a value. */
2858
2859 switch (code)
2860 {
2861 case INTEGER_CST:
2862 p = (char *) &TREE_INT_CST_ELT (exp, 0);
2863 len = TREE_INT_CST_NUNITS (exp) * sizeof (HOST_WIDE_INT);
2864 break;
2865
2866 case REAL_CST:
2867 return real_hash (TREE_REAL_CST_PTR (exp));
2868
2869 case FIXED_CST:
2870 return fixed_hash (TREE_FIXED_CST_PTR (exp));
2871
2872 case STRING_CST:
2873 p = TREE_STRING_POINTER (exp);
2874 len = TREE_STRING_LENGTH (exp);
2875 break;
2876
2877 case COMPLEX_CST:
2878 return (const_hash_1 (TREE_REALPART (exp)) * 5
2879 + const_hash_1 (TREE_IMAGPART (exp)));
2880
2881 case VECTOR_CST:
2882 {
2883 unsigned i;
2884
2885 hi = 7 + VECTOR_CST_NELTS (exp);
2886
2887 for (i = 0; i < VECTOR_CST_NELTS (exp); ++i)
2888 hi = hi * 563 + const_hash_1 (VECTOR_CST_ELT (exp, i));
2889
2890 return hi;
2891 }
2892
2893 case CONSTRUCTOR:
2894 {
2895 unsigned HOST_WIDE_INT idx;
2896 tree value;
2897
2898 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2899
2900 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
2901 if (value)
2902 hi = hi * 603 + const_hash_1 (value);
2903
2904 return hi;
2905 }
2906
2907 case ADDR_EXPR:
2908 case FDESC_EXPR:
2909 {
2910 struct addr_const value;
2911
2912 decode_addr_const (exp, &value);
2913 switch (GET_CODE (value.base))
2914 {
2915 case SYMBOL_REF:
2916 /* Don't hash the address of the SYMBOL_REF;
2917 only use the offset and the symbol name. */
2918 hi = value.offset;
2919 p = XSTR (value.base, 0);
2920 for (i = 0; p[i] != 0; i++)
2921 hi = ((hi * 613) + (unsigned) (p[i]));
2922 break;
2923
2924 case LABEL_REF:
2925 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13;
2926 break;
2927
2928 default:
2929 gcc_unreachable ();
2930 }
2931 }
2932 return hi;
2933
2934 case PLUS_EXPR:
2935 case POINTER_PLUS_EXPR:
2936 case MINUS_EXPR:
2937 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2938 + const_hash_1 (TREE_OPERAND (exp, 1)));
2939
2940 CASE_CONVERT:
2941 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
2942
2943 default:
2944 /* A language specific constant. Just hash the code. */
2945 return code;
2946 }
2947
2948 /* Compute hashing function. */
2949 hi = len;
2950 for (i = 0; i < len; i++)
2951 hi = ((hi * 613) + (unsigned) (p[i]));
2952
2953 return hi;
2954 }
2955
2956 /* Wrapper of compare_constant, for the htab interface. */
2957 static int
2958 const_desc_eq (const void *p1, const void *p2)
2959 {
2960 const struct constant_descriptor_tree *const c1
2961 = (const struct constant_descriptor_tree *) p1;
2962 const struct constant_descriptor_tree *const c2
2963 = (const struct constant_descriptor_tree *) p2;
2964 if (c1->hash != c2->hash)
2965 return 0;
2966 return compare_constant (c1->value, c2->value);
2967 }
2968
2969 /* Compare t1 and t2, and return 1 only if they are known to result in
2970 the same bit pattern on output. */
2971
2972 static int
2973 compare_constant (const tree t1, const tree t2)
2974 {
2975 enum tree_code typecode;
2976
2977 if (t1 == NULL_TREE)
2978 return t2 == NULL_TREE;
2979 if (t2 == NULL_TREE)
2980 return 0;
2981
2982 if (TREE_CODE (t1) != TREE_CODE (t2))
2983 return 0;
2984
2985 switch (TREE_CODE (t1))
2986 {
2987 case INTEGER_CST:
2988 /* Integer constants are the same only if the same width of type. */
2989 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2990 return 0;
2991 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2992 return 0;
2993 return tree_int_cst_equal (t1, t2);
2994
2995 case REAL_CST:
2996 /* Real constants are the same only if the same width of type. */
2997 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2998 return 0;
2999
3000 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
3001
3002 case FIXED_CST:
3003 /* Fixed constants are the same only if the same width of type. */
3004 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3005 return 0;
3006
3007 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
3008
3009 case STRING_CST:
3010 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3011 return 0;
3012
3013 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
3014 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
3015 TREE_STRING_LENGTH (t1)));
3016
3017 case COMPLEX_CST:
3018 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
3019 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
3020
3021 case VECTOR_CST:
3022 {
3023 unsigned i;
3024
3025 if (VECTOR_CST_NELTS (t1) != VECTOR_CST_NELTS (t2))
3026 return 0;
3027
3028 for (i = 0; i < VECTOR_CST_NELTS (t1); ++i)
3029 if (!compare_constant (VECTOR_CST_ELT (t1, i),
3030 VECTOR_CST_ELT (t2, i)))
3031 return 0;
3032
3033 return 1;
3034 }
3035
3036 case CONSTRUCTOR:
3037 {
3038 vec<constructor_elt, va_gc> *v1, *v2;
3039 unsigned HOST_WIDE_INT idx;
3040
3041 typecode = TREE_CODE (TREE_TYPE (t1));
3042 if (typecode != TREE_CODE (TREE_TYPE (t2)))
3043 return 0;
3044
3045 if (typecode == ARRAY_TYPE)
3046 {
3047 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
3048 /* For arrays, check that the sizes all match. */
3049 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
3050 || size_1 == -1
3051 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
3052 return 0;
3053 }
3054 else
3055 {
3056 /* For record and union constructors, require exact type
3057 equality. */
3058 if (TREE_TYPE (t1) != TREE_TYPE (t2))
3059 return 0;
3060 }
3061
3062 v1 = CONSTRUCTOR_ELTS (t1);
3063 v2 = CONSTRUCTOR_ELTS (t2);
3064 if (vec_safe_length (v1) != vec_safe_length (v2))
3065 return 0;
3066
3067 for (idx = 0; idx < vec_safe_length (v1); ++idx)
3068 {
3069 constructor_elt *c1 = &(*v1)[idx];
3070 constructor_elt *c2 = &(*v2)[idx];
3071
3072 /* Check that each value is the same... */
3073 if (!compare_constant (c1->value, c2->value))
3074 return 0;
3075 /* ... and that they apply to the same fields! */
3076 if (typecode == ARRAY_TYPE)
3077 {
3078 if (!compare_constant (c1->index, c2->index))
3079 return 0;
3080 }
3081 else
3082 {
3083 if (c1->index != c2->index)
3084 return 0;
3085 }
3086 }
3087
3088 return 1;
3089 }
3090
3091 case ADDR_EXPR:
3092 case FDESC_EXPR:
3093 {
3094 struct addr_const value1, value2;
3095 enum rtx_code code;
3096 int ret;
3097
3098 decode_addr_const (t1, &value1);
3099 decode_addr_const (t2, &value2);
3100
3101 if (value1.offset != value2.offset)
3102 return 0;
3103
3104 code = GET_CODE (value1.base);
3105 if (code != GET_CODE (value2.base))
3106 return 0;
3107
3108 switch (code)
3109 {
3110 case SYMBOL_REF:
3111 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3112 break;
3113
3114 case LABEL_REF:
3115 ret = (CODE_LABEL_NUMBER (XEXP (value1.base, 0))
3116 == CODE_LABEL_NUMBER (XEXP (value2.base, 0)));
3117 break;
3118
3119 default:
3120 gcc_unreachable ();
3121 }
3122 return ret;
3123 }
3124
3125 case PLUS_EXPR:
3126 case POINTER_PLUS_EXPR:
3127 case MINUS_EXPR:
3128 case RANGE_EXPR:
3129 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3130 && compare_constant (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3131
3132 CASE_CONVERT:
3133 case VIEW_CONVERT_EXPR:
3134 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3135
3136 default:
3137 return 0;
3138 }
3139
3140 gcc_unreachable ();
3141 }
3142 \f
3143 /* Return the section into which constant EXP should be placed. */
3144
3145 static section *
3146 get_constant_section (tree exp, unsigned int align)
3147 {
3148 return targetm.asm_out.select_section (exp,
3149 compute_reloc_for_constant (exp),
3150 align);
3151 }
3152
3153 /* Return the size of constant EXP in bytes. */
3154
3155 static HOST_WIDE_INT
3156 get_constant_size (tree exp)
3157 {
3158 HOST_WIDE_INT size;
3159
3160 size = int_size_in_bytes (TREE_TYPE (exp));
3161 if (TREE_CODE (exp) == STRING_CST)
3162 size = MAX (TREE_STRING_LENGTH (exp), size);
3163 return size;
3164 }
3165
3166 /* Subroutine of output_constant_def:
3167 No constant equal to EXP is known to have been output.
3168 Make a constant descriptor to enter EXP in the hash table.
3169 Assign the label number and construct RTL to refer to the
3170 constant's location in memory.
3171 Caller is responsible for updating the hash table. */
3172
3173 static struct constant_descriptor_tree *
3174 build_constant_desc (tree exp)
3175 {
3176 struct constant_descriptor_tree *desc;
3177 rtx symbol, rtl;
3178 char label[256];
3179 int labelno;
3180 tree decl;
3181
3182 desc = ggc_alloc<constant_descriptor_tree> ();
3183 desc->value = exp;
3184
3185 /* Create a string containing the label name, in LABEL. */
3186 labelno = const_labelno++;
3187 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3188
3189 /* Construct the VAR_DECL associated with the constant. */
3190 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3191 TREE_TYPE (exp));
3192 DECL_ARTIFICIAL (decl) = 1;
3193 DECL_IGNORED_P (decl) = 1;
3194 TREE_READONLY (decl) = 1;
3195 TREE_STATIC (decl) = 1;
3196 TREE_ADDRESSABLE (decl) = 1;
3197 /* We don't set the RTL yet as this would cause varpool to assume that the
3198 variable is referenced. Moreover, it would just be dropped in LTO mode.
3199 Instead we set the flag that will be recognized in make_decl_rtl. */
3200 DECL_IN_CONSTANT_POOL (decl) = 1;
3201 DECL_INITIAL (decl) = desc->value;
3202 /* ??? CONSTANT_ALIGNMENT hasn't been updated for vector types on most
3203 architectures so use DATA_ALIGNMENT as well, except for strings. */
3204 if (TREE_CODE (exp) == STRING_CST)
3205 {
3206 #ifdef CONSTANT_ALIGNMENT
3207 DECL_ALIGN (decl) = CONSTANT_ALIGNMENT (exp, DECL_ALIGN (decl));
3208 #endif
3209 }
3210 else
3211 align_variable (decl, 0);
3212
3213 /* Now construct the SYMBOL_REF and the MEM. */
3214 if (use_object_blocks_p ())
3215 {
3216 section *sect = get_constant_section (exp, DECL_ALIGN (decl));
3217 symbol = create_block_symbol (ggc_strdup (label),
3218 get_block_for_section (sect), -1);
3219 }
3220 else
3221 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3222 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3223 SET_SYMBOL_REF_DECL (symbol, decl);
3224 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3225
3226 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3227 set_mem_attributes (rtl, exp, 1);
3228 set_mem_alias_set (rtl, 0);
3229 set_mem_alias_set (rtl, const_alias_set);
3230
3231 /* We cannot share RTX'es in pool entries.
3232 Mark this piece of RTL as required for unsharing. */
3233 RTX_FLAG (rtl, used) = 1;
3234
3235 /* Set flags or add text to the name to record information, such as
3236 that it is a local symbol. If the name is changed, the macro
3237 ASM_OUTPUT_LABELREF will have to know how to strip this
3238 information. This call might invalidate our local variable
3239 SYMBOL; we can't use it afterward. */
3240 targetm.encode_section_info (exp, rtl, true);
3241
3242 desc->rtl = rtl;
3243
3244 return desc;
3245 }
3246
3247 /* Return an rtx representing a reference to constant data in memory
3248 for the constant expression EXP.
3249
3250 If assembler code for such a constant has already been output,
3251 return an rtx to refer to it.
3252 Otherwise, output such a constant in memory
3253 and generate an rtx for it.
3254
3255 If DEFER is nonzero, this constant can be deferred and output only
3256 if referenced in the function after all optimizations.
3257
3258 `const_desc_table' records which constants already have label strings. */
3259
3260 rtx
3261 output_constant_def (tree exp, int defer)
3262 {
3263 struct constant_descriptor_tree *desc;
3264 struct constant_descriptor_tree key;
3265 void **loc;
3266
3267 /* Look up EXP in the table of constant descriptors. If we didn't find
3268 it, create a new one. */
3269 key.value = exp;
3270 key.hash = const_hash_1 (exp);
3271 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3272
3273 desc = (struct constant_descriptor_tree *) *loc;
3274 if (desc == 0)
3275 {
3276 desc = build_constant_desc (exp);
3277 desc->hash = key.hash;
3278 *loc = desc;
3279 }
3280
3281 maybe_output_constant_def_contents (desc, defer);
3282 return desc->rtl;
3283 }
3284
3285 /* Subroutine of output_constant_def: Decide whether or not we need to
3286 output the constant DESC now, and if so, do it. */
3287 static void
3288 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3289 int defer)
3290 {
3291 rtx symbol = XEXP (desc->rtl, 0);
3292 tree exp = desc->value;
3293
3294 if (flag_syntax_only)
3295 return;
3296
3297 if (TREE_ASM_WRITTEN (exp))
3298 /* Already output; don't do it again. */
3299 return;
3300
3301 /* We can always defer constants as long as the context allows
3302 doing so. */
3303 if (defer)
3304 {
3305 /* Increment n_deferred_constants if it exists. It needs to be at
3306 least as large as the number of constants actually referred to
3307 by the function. If it's too small we'll stop looking too early
3308 and fail to emit constants; if it's too large we'll only look
3309 through the entire function when we could have stopped earlier. */
3310 if (cfun)
3311 n_deferred_constants++;
3312 return;
3313 }
3314
3315 output_constant_def_contents (symbol);
3316 }
3317
3318 /* Subroutine of output_constant_def_contents. Output the definition
3319 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3320 constant's alignment in bits. */
3321
3322 static void
3323 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3324 {
3325 HOST_WIDE_INT size;
3326
3327 size = get_constant_size (exp);
3328
3329 /* Do any machine/system dependent processing of the constant. */
3330 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3331
3332 /* Output the value of EXP. */
3333 output_constant (exp, size, align);
3334 }
3335
3336 /* We must output the constant data referred to by SYMBOL; do so. */
3337
3338 static void
3339 output_constant_def_contents (rtx symbol)
3340 {
3341 tree decl = SYMBOL_REF_DECL (symbol);
3342 tree exp = DECL_INITIAL (decl);
3343 unsigned int align;
3344 bool asan_protected = false;
3345
3346 /* Make sure any other constants whose addresses appear in EXP
3347 are assigned label numbers. */
3348 output_addressed_constants (exp);
3349
3350 /* We are no longer deferring this constant. */
3351 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3352
3353 if ((flag_sanitize & SANITIZE_ADDRESS)
3354 && TREE_CODE (exp) == STRING_CST
3355 && asan_protect_global (exp))
3356 {
3357 asan_protected = true;
3358 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
3359 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
3360 }
3361
3362 /* If the constant is part of an object block, make sure that the
3363 decl has been positioned within its block, but do not write out
3364 its definition yet. output_object_blocks will do that later. */
3365 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3366 place_block_symbol (symbol);
3367 else
3368 {
3369 align = DECL_ALIGN (decl);
3370 switch_to_section (get_constant_section (exp, align));
3371 if (align > BITS_PER_UNIT)
3372 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3373 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3374 if (asan_protected)
3375 {
3376 HOST_WIDE_INT size = get_constant_size (exp);
3377 assemble_zeros (asan_red_zone_size (size));
3378 }
3379 }
3380 }
3381
3382 /* Look up EXP in the table of constant descriptors. Return the rtl
3383 if it has been emitted, else null. */
3384
3385 rtx
3386 lookup_constant_def (tree exp)
3387 {
3388 struct constant_descriptor_tree *desc;
3389 struct constant_descriptor_tree key;
3390
3391 key.value = exp;
3392 key.hash = const_hash_1 (exp);
3393 desc = (struct constant_descriptor_tree *)
3394 htab_find_with_hash (const_desc_htab, &key, key.hash);
3395
3396 return (desc ? desc->rtl : NULL_RTX);
3397 }
3398
3399 /* Return a tree representing a reference to constant data in memory
3400 for the constant expression EXP.
3401
3402 This is the counterpart of output_constant_def at the Tree level. */
3403
3404 tree
3405 tree_output_constant_def (tree exp)
3406 {
3407 struct constant_descriptor_tree *desc, key;
3408 void **loc;
3409 tree decl;
3410
3411 /* Look up EXP in the table of constant descriptors. If we didn't find
3412 it, create a new one. */
3413 key.value = exp;
3414 key.hash = const_hash_1 (exp);
3415 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3416
3417 desc = (struct constant_descriptor_tree *) *loc;
3418 if (desc == 0)
3419 {
3420 desc = build_constant_desc (exp);
3421 desc->hash = key.hash;
3422 *loc = desc;
3423 }
3424
3425 decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3426 varpool_node::finalize_decl (decl);
3427 return decl;
3428 }
3429 \f
3430 /* Used in the hash tables to avoid outputting the same constant
3431 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3432 are output once per function, not once per file. */
3433 /* ??? Only a few targets need per-function constant pools. Most
3434 can use one per-file pool. Should add a targetm bit to tell the
3435 difference. */
3436
3437 struct GTY(()) rtx_constant_pool {
3438 /* Pointers to first and last constant in pool, as ordered by offset. */
3439 struct constant_descriptor_rtx *first;
3440 struct constant_descriptor_rtx *last;
3441
3442 /* Hash facility for making memory-constants from constant rtl-expressions.
3443 It is used on RISC machines where immediate integer arguments and
3444 constant addresses are restricted so that such constants must be stored
3445 in memory. */
3446 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_htab;
3447
3448 /* Current offset in constant pool (does not include any
3449 machine-specific header). */
3450 HOST_WIDE_INT offset;
3451 };
3452
3453 struct GTY((chain_next ("%h.next"))) constant_descriptor_rtx {
3454 struct constant_descriptor_rtx *next;
3455 rtx mem;
3456 rtx sym;
3457 rtx constant;
3458 HOST_WIDE_INT offset;
3459 hashval_t hash;
3460 enum machine_mode mode;
3461 unsigned int align;
3462 int labelno;
3463 int mark;
3464 };
3465
3466 /* Hash and compare functions for const_rtx_htab. */
3467
3468 static hashval_t
3469 const_desc_rtx_hash (const void *ptr)
3470 {
3471 const struct constant_descriptor_rtx *const desc
3472 = (const struct constant_descriptor_rtx *) ptr;
3473 return desc->hash;
3474 }
3475
3476 static int
3477 const_desc_rtx_eq (const void *a, const void *b)
3478 {
3479 const struct constant_descriptor_rtx *const x
3480 = (const struct constant_descriptor_rtx *) a;
3481 const struct constant_descriptor_rtx *const y
3482 = (const struct constant_descriptor_rtx *) b;
3483
3484 if (x->mode != y->mode)
3485 return 0;
3486 return rtx_equal_p (x->constant, y->constant);
3487 }
3488
3489 /* Hash one component of a constant. */
3490
3491 static hashval_t
3492 const_rtx_hash_1 (const_rtx x)
3493 {
3494 unsigned HOST_WIDE_INT hwi;
3495 enum machine_mode mode;
3496 enum rtx_code code;
3497 hashval_t h;
3498 int i;
3499
3500 code = GET_CODE (x);
3501 mode = GET_MODE (x);
3502 h = (hashval_t) code * 1048573 + mode;
3503
3504 switch (code)
3505 {
3506 case CONST_INT:
3507 hwi = INTVAL (x);
3508
3509 fold_hwi:
3510 {
3511 int shift = sizeof (hashval_t) * CHAR_BIT;
3512 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3513
3514 h ^= (hashval_t) hwi;
3515 for (i = 1; i < n; ++i)
3516 {
3517 hwi >>= shift;
3518 h ^= (hashval_t) hwi;
3519 }
3520 }
3521 break;
3522
3523 case CONST_WIDE_INT:
3524 hwi = GET_MODE_PRECISION (mode);
3525 {
3526 for (i = 0; i < CONST_WIDE_INT_NUNITS (x); i++)
3527 hwi ^= CONST_WIDE_INT_ELT (x, i);
3528 goto fold_hwi;
3529 }
3530
3531 case CONST_DOUBLE:
3532 if (TARGET_SUPPORTS_WIDE_INT == 0 && mode == VOIDmode)
3533 {
3534 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3535 goto fold_hwi;
3536 }
3537 else
3538 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3539 break;
3540
3541 case CONST_FIXED:
3542 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3543 break;
3544
3545 case SYMBOL_REF:
3546 h ^= htab_hash_string (XSTR (x, 0));
3547 break;
3548
3549 case LABEL_REF:
3550 h = h * 251 + CODE_LABEL_NUMBER (XEXP (x, 0));
3551 break;
3552
3553 case UNSPEC:
3554 case UNSPEC_VOLATILE:
3555 h = h * 251 + XINT (x, 1);
3556 break;
3557
3558 default:
3559 break;
3560 }
3561
3562 return h;
3563 }
3564
3565 /* Compute a hash value for X, which should be a constant. */
3566
3567 static hashval_t
3568 const_rtx_hash (rtx x)
3569 {
3570 hashval_t h = 0;
3571 subrtx_iterator::array_type array;
3572 FOR_EACH_SUBRTX (iter, array, x, ALL)
3573 h = h * 509 + const_rtx_hash_1 (*iter);
3574 return h;
3575 }
3576
3577 \f
3578 /* Create and return a new rtx constant pool. */
3579
3580 static struct rtx_constant_pool *
3581 create_constant_pool (void)
3582 {
3583 struct rtx_constant_pool *pool;
3584
3585 pool = ggc_alloc<rtx_constant_pool> ();
3586 pool->const_rtx_htab = htab_create_ggc (31, const_desc_rtx_hash,
3587 const_desc_rtx_eq, NULL);
3588 pool->first = NULL;
3589 pool->last = NULL;
3590 pool->offset = 0;
3591 return pool;
3592 }
3593
3594 /* Initialize constant pool hashing for a new function. */
3595
3596 void
3597 init_varasm_status (void)
3598 {
3599 crtl->varasm.pool = create_constant_pool ();
3600 crtl->varasm.deferred_constants = 0;
3601 }
3602 \f
3603 /* Given a MINUS expression, simplify it if both sides
3604 include the same symbol. */
3605
3606 rtx
3607 simplify_subtraction (rtx x)
3608 {
3609 rtx r = simplify_rtx (x);
3610 return r ? r : x;
3611 }
3612 \f
3613 /* Given a constant rtx X, make (or find) a memory constant for its value
3614 and return a MEM rtx to refer to it in memory. */
3615
3616 rtx
3617 force_const_mem (enum machine_mode mode, rtx x)
3618 {
3619 struct constant_descriptor_rtx *desc, tmp;
3620 struct rtx_constant_pool *pool;
3621 char label[256];
3622 rtx def, symbol;
3623 hashval_t hash;
3624 unsigned int align;
3625 void **slot;
3626
3627 /* If we're not allowed to drop X into the constant pool, don't. */
3628 if (targetm.cannot_force_const_mem (mode, x))
3629 return NULL_RTX;
3630
3631 /* Record that this function has used a constant pool entry. */
3632 crtl->uses_const_pool = 1;
3633
3634 /* Decide which pool to use. */
3635 pool = (targetm.use_blocks_for_constant_p (mode, x)
3636 ? shared_constant_pool
3637 : crtl->varasm.pool);
3638
3639 /* Lookup the value in the hashtable. */
3640 tmp.constant = x;
3641 tmp.mode = mode;
3642 hash = const_rtx_hash (x);
3643 slot = htab_find_slot_with_hash (pool->const_rtx_htab, &tmp, hash, INSERT);
3644 desc = (struct constant_descriptor_rtx *) *slot;
3645
3646 /* If the constant was already present, return its memory. */
3647 if (desc)
3648 return copy_rtx (desc->mem);
3649
3650 /* Otherwise, create a new descriptor. */
3651 desc = ggc_alloc<constant_descriptor_rtx> ();
3652 *slot = desc;
3653
3654 /* Align the location counter as required by EXP's data type. */
3655 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3656 #ifdef CONSTANT_ALIGNMENT
3657 {
3658 tree type = lang_hooks.types.type_for_mode (mode, 0);
3659 if (type != NULL_TREE)
3660 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3661 }
3662 #endif
3663
3664 pool->offset += (align / BITS_PER_UNIT) - 1;
3665 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3666
3667 desc->next = NULL;
3668 desc->constant = copy_rtx (tmp.constant);
3669 desc->offset = pool->offset;
3670 desc->hash = hash;
3671 desc->mode = mode;
3672 desc->align = align;
3673 desc->labelno = const_labelno;
3674 desc->mark = 0;
3675
3676 pool->offset += GET_MODE_SIZE (mode);
3677 if (pool->last)
3678 pool->last->next = desc;
3679 else
3680 pool->first = pool->last = desc;
3681 pool->last = desc;
3682
3683 /* Create a string containing the label name, in LABEL. */
3684 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3685 ++const_labelno;
3686
3687 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3688 the constants pool. */
3689 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3690 {
3691 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3692 symbol = create_block_symbol (ggc_strdup (label),
3693 get_block_for_section (sect), -1);
3694 }
3695 else
3696 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3697 desc->sym = symbol;
3698 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3699 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3700 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3701
3702 /* Construct the MEM. */
3703 desc->mem = def = gen_const_mem (mode, symbol);
3704 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3705 set_mem_align (def, align);
3706
3707 /* If we're dropping a label to the constant pool, make sure we
3708 don't delete it. */
3709 if (GET_CODE (x) == LABEL_REF)
3710 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3711
3712 return copy_rtx (def);
3713 }
3714 \f
3715 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3716
3717 rtx
3718 get_pool_constant (const_rtx addr)
3719 {
3720 return SYMBOL_REF_CONSTANT (addr)->constant;
3721 }
3722
3723 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3724 and whether it has been output or not. */
3725
3726 rtx
3727 get_pool_constant_mark (rtx addr, bool *pmarked)
3728 {
3729 struct constant_descriptor_rtx *desc;
3730
3731 desc = SYMBOL_REF_CONSTANT (addr);
3732 *pmarked = (desc->mark != 0);
3733 return desc->constant;
3734 }
3735
3736 /* Similar, return the mode. */
3737
3738 enum machine_mode
3739 get_pool_mode (const_rtx addr)
3740 {
3741 return SYMBOL_REF_CONSTANT (addr)->mode;
3742 }
3743
3744 /* Return the size of the constant pool. */
3745
3746 int
3747 get_pool_size (void)
3748 {
3749 return crtl->varasm.pool->offset;
3750 }
3751 \f
3752 /* Worker function for output_constant_pool_1. Emit assembly for X
3753 in MODE with known alignment ALIGN. */
3754
3755 static void
3756 output_constant_pool_2 (enum machine_mode mode, rtx x, unsigned int align)
3757 {
3758 switch (GET_MODE_CLASS (mode))
3759 {
3760 case MODE_FLOAT:
3761 case MODE_DECIMAL_FLOAT:
3762 {
3763 REAL_VALUE_TYPE r;
3764
3765 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3766 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3767 assemble_real (r, mode, align);
3768 break;
3769 }
3770
3771 case MODE_INT:
3772 case MODE_PARTIAL_INT:
3773 case MODE_FRACT:
3774 case MODE_UFRACT:
3775 case MODE_ACCUM:
3776 case MODE_UACCUM:
3777 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3778 break;
3779
3780 case MODE_VECTOR_FLOAT:
3781 case MODE_VECTOR_INT:
3782 case MODE_VECTOR_FRACT:
3783 case MODE_VECTOR_UFRACT:
3784 case MODE_VECTOR_ACCUM:
3785 case MODE_VECTOR_UACCUM:
3786 {
3787 int i, units;
3788 enum machine_mode submode = GET_MODE_INNER (mode);
3789 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3790
3791 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3792 units = CONST_VECTOR_NUNITS (x);
3793
3794 for (i = 0; i < units; i++)
3795 {
3796 rtx elt = CONST_VECTOR_ELT (x, i);
3797 output_constant_pool_2 (submode, elt, i ? subalign : align);
3798 }
3799 }
3800 break;
3801
3802 default:
3803 gcc_unreachable ();
3804 }
3805 }
3806
3807 /* Worker function for output_constant_pool. Emit constant DESC,
3808 giving it ALIGN bits of alignment. */
3809
3810 static void
3811 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3812 unsigned int align)
3813 {
3814 rtx x, tmp;
3815
3816 x = desc->constant;
3817
3818 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3819 whose CODE_LABEL has been deleted. This can occur if a jump table
3820 is eliminated by optimization. If so, write a constant of zero
3821 instead. Note that this can also happen by turning the
3822 CODE_LABEL into a NOTE. */
3823 /* ??? This seems completely and utterly wrong. Certainly it's
3824 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3825 functioning even with INSN_DELETED_P and friends. */
3826
3827 tmp = x;
3828 switch (GET_CODE (tmp))
3829 {
3830 case CONST:
3831 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3832 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
3833 break;
3834 tmp = XEXP (XEXP (tmp, 0), 0);
3835 /* FALLTHRU */
3836
3837 case LABEL_REF:
3838 tmp = XEXP (tmp, 0);
3839 gcc_assert (!INSN_DELETED_P (tmp));
3840 gcc_assert (!NOTE_P (tmp)
3841 || NOTE_KIND (tmp) != NOTE_INSN_DELETED);
3842 break;
3843
3844 default:
3845 break;
3846 }
3847
3848 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3849 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3850 align, desc->labelno, done);
3851 #endif
3852
3853 assemble_align (align);
3854
3855 /* Output the label. */
3856 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3857
3858 /* Output the data. */
3859 output_constant_pool_2 (desc->mode, x, align);
3860
3861 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3862 sections have proper size. */
3863 if (align > GET_MODE_BITSIZE (desc->mode)
3864 && in_section
3865 && (in_section->common.flags & SECTION_MERGE))
3866 assemble_align (align);
3867
3868 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3869 done:
3870 #endif
3871 return;
3872 }
3873
3874 /* Mark all constants that are referenced by SYMBOL_REFs in X.
3875 Emit referenced deferred strings. */
3876
3877 static void
3878 mark_constants_in_pattern (rtx insn)
3879 {
3880 subrtx_iterator::array_type array;
3881 FOR_EACH_SUBRTX (iter, array, PATTERN (insn), ALL)
3882 {
3883 const_rtx x = *iter;
3884 if (GET_CODE (x) == SYMBOL_REF)
3885 {
3886 if (CONSTANT_POOL_ADDRESS_P (x))
3887 {
3888 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
3889 if (desc->mark == 0)
3890 {
3891 desc->mark = 1;
3892 iter.substitute (desc->constant);
3893 }
3894 }
3895 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3896 {
3897 tree decl = SYMBOL_REF_DECL (x);
3898 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
3899 {
3900 n_deferred_constants--;
3901 output_constant_def_contents (CONST_CAST_RTX (x));
3902 }
3903 }
3904 }
3905 }
3906 }
3907
3908 /* Look through appropriate parts of INSN, marking all entries in the
3909 constant pool which are actually being used. Entries that are only
3910 referenced by other constants are also marked as used. Emit
3911 deferred strings that are used. */
3912
3913 static void
3914 mark_constants (rtx_insn *insn)
3915 {
3916 if (!INSN_P (insn))
3917 return;
3918
3919 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3920 insns, not any notes that may be attached. We don't want to mark
3921 a constant just because it happens to appear in a REG_EQUIV note. */
3922 if (rtx_sequence *seq = dyn_cast <rtx_sequence *> (PATTERN (insn)))
3923 {
3924 int i, n = seq->len ();
3925 for (i = 0; i < n; ++i)
3926 {
3927 rtx subinsn = seq->element (i);
3928 if (INSN_P (subinsn))
3929 mark_constants_in_pattern (subinsn);
3930 }
3931 }
3932 else
3933 mark_constants_in_pattern (insn);
3934 }
3935
3936 /* Look through the instructions for this function, and mark all the
3937 entries in POOL which are actually being used. Emit deferred constants
3938 which have indeed been used. */
3939
3940 static void
3941 mark_constant_pool (void)
3942 {
3943 rtx_insn *insn;
3944
3945 if (!crtl->uses_const_pool && n_deferred_constants == 0)
3946 return;
3947
3948 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3949 mark_constants (insn);
3950 }
3951
3952 /* Write all the constants in POOL. */
3953
3954 static void
3955 output_constant_pool_contents (struct rtx_constant_pool *pool)
3956 {
3957 struct constant_descriptor_rtx *desc;
3958
3959 for (desc = pool->first; desc ; desc = desc->next)
3960 if (desc->mark)
3961 {
3962 /* If the constant is part of an object_block, make sure that
3963 the constant has been positioned within its block, but do not
3964 write out its definition yet. output_object_blocks will do
3965 that later. */
3966 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
3967 && SYMBOL_REF_BLOCK (desc->sym))
3968 place_block_symbol (desc->sym);
3969 else
3970 {
3971 switch_to_section (targetm.asm_out.select_rtx_section
3972 (desc->mode, desc->constant, desc->align));
3973 output_constant_pool_1 (desc, desc->align);
3974 }
3975 }
3976 }
3977
3978 /* Mark all constants that are used in the current function, then write
3979 out the function's private constant pool. */
3980
3981 static void
3982 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
3983 tree fndecl ATTRIBUTE_UNUSED)
3984 {
3985 struct rtx_constant_pool *pool = crtl->varasm.pool;
3986
3987 /* It is possible for gcc to call force_const_mem and then to later
3988 discard the instructions which refer to the constant. In such a
3989 case we do not need to output the constant. */
3990 mark_constant_pool ();
3991
3992 #ifdef ASM_OUTPUT_POOL_PROLOGUE
3993 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
3994 #endif
3995
3996 output_constant_pool_contents (pool);
3997
3998 #ifdef ASM_OUTPUT_POOL_EPILOGUE
3999 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
4000 #endif
4001 }
4002 \f
4003 /* Write the contents of the shared constant pool. */
4004
4005 void
4006 output_shared_constant_pool (void)
4007 {
4008 output_constant_pool_contents (shared_constant_pool);
4009 }
4010 \f
4011 /* Determine what kind of relocations EXP may need. */
4012
4013 int
4014 compute_reloc_for_constant (tree exp)
4015 {
4016 int reloc = 0, reloc2;
4017 tree tem;
4018
4019 switch (TREE_CODE (exp))
4020 {
4021 case ADDR_EXPR:
4022 case FDESC_EXPR:
4023 /* Go inside any operations that get_inner_reference can handle and see
4024 if what's inside is a constant: no need to do anything here for
4025 addresses of variables or functions. */
4026 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4027 tem = TREE_OPERAND (tem, 0))
4028 ;
4029
4030 if (TREE_CODE (tem) == MEM_REF
4031 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4032 {
4033 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4034 break;
4035 }
4036
4037 if (!targetm.binds_local_p (tem))
4038 reloc |= 2;
4039 else
4040 reloc |= 1;
4041 break;
4042
4043 case PLUS_EXPR:
4044 case POINTER_PLUS_EXPR:
4045 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4046 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4047 break;
4048
4049 case MINUS_EXPR:
4050 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4051 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4052 /* The difference of two local labels is computable at link time. */
4053 if (reloc == 1 && reloc2 == 1)
4054 reloc = 0;
4055 else
4056 reloc |= reloc2;
4057 break;
4058
4059 CASE_CONVERT:
4060 case VIEW_CONVERT_EXPR:
4061 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4062 break;
4063
4064 case CONSTRUCTOR:
4065 {
4066 unsigned HOST_WIDE_INT idx;
4067 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4068 if (tem != 0)
4069 reloc |= compute_reloc_for_constant (tem);
4070 }
4071 break;
4072
4073 default:
4074 break;
4075 }
4076 return reloc;
4077 }
4078
4079 /* Find all the constants whose addresses are referenced inside of EXP,
4080 and make sure assembler code with a label has been output for each one.
4081 Indicate whether an ADDR_EXPR has been encountered. */
4082
4083 static void
4084 output_addressed_constants (tree exp)
4085 {
4086 tree tem;
4087
4088 switch (TREE_CODE (exp))
4089 {
4090 case ADDR_EXPR:
4091 case FDESC_EXPR:
4092 /* Go inside any operations that get_inner_reference can handle and see
4093 if what's inside is a constant: no need to do anything here for
4094 addresses of variables or functions. */
4095 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4096 tem = TREE_OPERAND (tem, 0))
4097 ;
4098
4099 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4100 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4101 tem = DECL_INITIAL (tem);
4102
4103 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4104 output_constant_def (tem, 0);
4105
4106 if (TREE_CODE (tem) == MEM_REF)
4107 output_addressed_constants (TREE_OPERAND (tem, 0));
4108 break;
4109
4110 case PLUS_EXPR:
4111 case POINTER_PLUS_EXPR:
4112 case MINUS_EXPR:
4113 output_addressed_constants (TREE_OPERAND (exp, 1));
4114 /* Fall through. */
4115
4116 CASE_CONVERT:
4117 case VIEW_CONVERT_EXPR:
4118 output_addressed_constants (TREE_OPERAND (exp, 0));
4119 break;
4120
4121 case CONSTRUCTOR:
4122 {
4123 unsigned HOST_WIDE_INT idx;
4124 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4125 if (tem != 0)
4126 output_addressed_constants (tem);
4127 }
4128 break;
4129
4130 default:
4131 break;
4132 }
4133 }
4134 \f
4135 /* Whether a constructor CTOR is a valid static constant initializer if all
4136 its elements are. This used to be internal to initializer_constant_valid_p
4137 and has been exposed to let other functions like categorize_ctor_elements
4138 evaluate the property while walking a constructor for other purposes. */
4139
4140 bool
4141 constructor_static_from_elts_p (const_tree ctor)
4142 {
4143 return (TREE_CONSTANT (ctor)
4144 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4145 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4146 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4147 }
4148
4149 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4150 tree *cache);
4151
4152 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4153 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4154 which are valid when ENDTYPE is an integer of any size; in
4155 particular, this does not accept a pointer minus a constant. This
4156 returns null_pointer_node if the VALUE is an absolute constant
4157 which can be used to initialize a static variable. Otherwise it
4158 returns NULL. */
4159
4160 static tree
4161 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4162 {
4163 tree op0, op1;
4164
4165 if (!INTEGRAL_TYPE_P (endtype))
4166 return NULL_TREE;
4167
4168 op0 = TREE_OPERAND (value, 0);
4169 op1 = TREE_OPERAND (value, 1);
4170
4171 /* Like STRIP_NOPS except allow the operand mode to widen. This
4172 works around a feature of fold that simplifies (int)(p1 - p2) to
4173 ((int)p1 - (int)p2) under the theory that the narrower operation
4174 is cheaper. */
4175
4176 while (CONVERT_EXPR_P (op0)
4177 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4178 {
4179 tree inner = TREE_OPERAND (op0, 0);
4180 if (inner == error_mark_node
4181 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4182 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
4183 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4184 break;
4185 op0 = inner;
4186 }
4187
4188 while (CONVERT_EXPR_P (op1)
4189 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4190 {
4191 tree inner = TREE_OPERAND (op1, 0);
4192 if (inner == error_mark_node
4193 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4194 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
4195 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4196 break;
4197 op1 = inner;
4198 }
4199
4200 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4201 if (!op0)
4202 return NULL_TREE;
4203
4204 op1 = initializer_constant_valid_p_1 (op1, endtype,
4205 cache ? cache + 2 : NULL);
4206 /* Both initializers must be known. */
4207 if (op1)
4208 {
4209 if (op0 == op1
4210 && (op0 == null_pointer_node
4211 || TREE_CODE (value) == MINUS_EXPR))
4212 return null_pointer_node;
4213
4214 /* Support differences between labels. */
4215 if (TREE_CODE (op0) == LABEL_DECL
4216 && TREE_CODE (op1) == LABEL_DECL)
4217 return null_pointer_node;
4218
4219 if (TREE_CODE (op0) == STRING_CST
4220 && TREE_CODE (op1) == STRING_CST
4221 && operand_equal_p (op0, op1, 1))
4222 return null_pointer_node;
4223 }
4224
4225 return NULL_TREE;
4226 }
4227
4228 /* Helper function of initializer_constant_valid_p.
4229 Return nonzero if VALUE is a valid constant-valued expression
4230 for use in initializing a static variable; one that can be an
4231 element of a "constant" initializer.
4232
4233 Return null_pointer_node if the value is absolute;
4234 if it is relocatable, return the variable that determines the relocation.
4235 We assume that VALUE has been folded as much as possible;
4236 therefore, we do not need to check for such things as
4237 arithmetic-combinations of integers.
4238
4239 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4240
4241 static tree
4242 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4243 {
4244 tree ret;
4245
4246 switch (TREE_CODE (value))
4247 {
4248 case CONSTRUCTOR:
4249 if (constructor_static_from_elts_p (value))
4250 {
4251 unsigned HOST_WIDE_INT idx;
4252 tree elt;
4253 bool absolute = true;
4254
4255 if (cache && cache[0] == value)
4256 return cache[1];
4257 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4258 {
4259 tree reloc;
4260 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4261 NULL);
4262 if (!reloc)
4263 {
4264 if (cache)
4265 {
4266 cache[0] = value;
4267 cache[1] = NULL_TREE;
4268 }
4269 return NULL_TREE;
4270 }
4271 if (reloc != null_pointer_node)
4272 absolute = false;
4273 }
4274 /* For a non-absolute relocation, there is no single
4275 variable that can be "the variable that determines the
4276 relocation." */
4277 if (cache)
4278 {
4279 cache[0] = value;
4280 cache[1] = absolute ? null_pointer_node : error_mark_node;
4281 }
4282 return absolute ? null_pointer_node : error_mark_node;
4283 }
4284
4285 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4286
4287 case INTEGER_CST:
4288 case VECTOR_CST:
4289 case REAL_CST:
4290 case FIXED_CST:
4291 case STRING_CST:
4292 case COMPLEX_CST:
4293 return null_pointer_node;
4294
4295 case ADDR_EXPR:
4296 case FDESC_EXPR:
4297 {
4298 tree op0 = staticp (TREE_OPERAND (value, 0));
4299 if (op0)
4300 {
4301 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4302 to be a constant, this is old-skool offsetof-like nonsense. */
4303 if (TREE_CODE (op0) == INDIRECT_REF
4304 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4305 return null_pointer_node;
4306 /* Taking the address of a nested function involves a trampoline,
4307 unless we don't need or want one. */
4308 if (TREE_CODE (op0) == FUNCTION_DECL
4309 && DECL_STATIC_CHAIN (op0)
4310 && !TREE_NO_TRAMPOLINE (value))
4311 return NULL_TREE;
4312 /* "&{...}" requires a temporary to hold the constructed
4313 object. */
4314 if (TREE_CODE (op0) == CONSTRUCTOR)
4315 return NULL_TREE;
4316 }
4317 return op0;
4318 }
4319
4320 case NON_LVALUE_EXPR:
4321 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4322 endtype, cache);
4323
4324 case VIEW_CONVERT_EXPR:
4325 {
4326 tree src = TREE_OPERAND (value, 0);
4327 tree src_type = TREE_TYPE (src);
4328 tree dest_type = TREE_TYPE (value);
4329
4330 /* Allow view-conversions from aggregate to non-aggregate type only
4331 if the bit pattern is fully preserved afterwards; otherwise, the
4332 RTL expander won't be able to apply a subsequent transformation
4333 to the underlying constructor. */
4334 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4335 {
4336 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4337 return initializer_constant_valid_p_1 (src, endtype, cache);
4338 else
4339 return NULL_TREE;
4340 }
4341
4342 /* Allow all other kinds of view-conversion. */
4343 return initializer_constant_valid_p_1 (src, endtype, cache);
4344 }
4345
4346 CASE_CONVERT:
4347 {
4348 tree src = TREE_OPERAND (value, 0);
4349 tree src_type = TREE_TYPE (src);
4350 tree dest_type = TREE_TYPE (value);
4351
4352 /* Allow conversions between pointer types, floating-point
4353 types, and offset types. */
4354 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4355 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4356 || (TREE_CODE (dest_type) == OFFSET_TYPE
4357 && TREE_CODE (src_type) == OFFSET_TYPE))
4358 return initializer_constant_valid_p_1 (src, endtype, cache);
4359
4360 /* Allow length-preserving conversions between integer types. */
4361 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4362 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4363 return initializer_constant_valid_p_1 (src, endtype, cache);
4364
4365 /* Allow conversions between other integer types only if
4366 explicit value. */
4367 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type))
4368 {
4369 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4370 if (inner == null_pointer_node)
4371 return null_pointer_node;
4372 break;
4373 }
4374
4375 /* Allow (int) &foo provided int is as wide as a pointer. */
4376 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4377 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4378 return initializer_constant_valid_p_1 (src, endtype, cache);
4379
4380 /* Likewise conversions from int to pointers, but also allow
4381 conversions from 0. */
4382 if ((POINTER_TYPE_P (dest_type)
4383 || TREE_CODE (dest_type) == OFFSET_TYPE)
4384 && INTEGRAL_TYPE_P (src_type))
4385 {
4386 if (TREE_CODE (src) == INTEGER_CST
4387 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4388 return null_pointer_node;
4389 if (integer_zerop (src))
4390 return null_pointer_node;
4391 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4392 return initializer_constant_valid_p_1 (src, endtype, cache);
4393 }
4394
4395 /* Allow conversions to struct or union types if the value
4396 inside is okay. */
4397 if (TREE_CODE (dest_type) == RECORD_TYPE
4398 || TREE_CODE (dest_type) == UNION_TYPE)
4399 return initializer_constant_valid_p_1 (src, endtype, cache);
4400 }
4401 break;
4402
4403 case POINTER_PLUS_EXPR:
4404 case PLUS_EXPR:
4405 /* Any valid floating-point constants will have been folded by now;
4406 with -frounding-math we hit this with addition of two constants. */
4407 if (TREE_CODE (endtype) == REAL_TYPE)
4408 return NULL_TREE;
4409 if (cache && cache[0] == value)
4410 return cache[1];
4411 if (! INTEGRAL_TYPE_P (endtype)
4412 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4413 {
4414 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4415 tree valid0
4416 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4417 endtype, ncache);
4418 tree valid1
4419 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4420 endtype, ncache + 2);
4421 /* If either term is absolute, use the other term's relocation. */
4422 if (valid0 == null_pointer_node)
4423 ret = valid1;
4424 else if (valid1 == null_pointer_node)
4425 ret = valid0;
4426 /* Support narrowing pointer differences. */
4427 else
4428 ret = narrowing_initializer_constant_valid_p (value, endtype,
4429 ncache);
4430 }
4431 else
4432 /* Support narrowing pointer differences. */
4433 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4434 if (cache)
4435 {
4436 cache[0] = value;
4437 cache[1] = ret;
4438 }
4439 return ret;
4440
4441 case MINUS_EXPR:
4442 if (TREE_CODE (endtype) == REAL_TYPE)
4443 return NULL_TREE;
4444 if (cache && cache[0] == value)
4445 return cache[1];
4446 if (! INTEGRAL_TYPE_P (endtype)
4447 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4448 {
4449 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4450 tree valid0
4451 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4452 endtype, ncache);
4453 tree valid1
4454 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4455 endtype, ncache + 2);
4456 /* Win if second argument is absolute. */
4457 if (valid1 == null_pointer_node)
4458 ret = valid0;
4459 /* Win if both arguments have the same relocation.
4460 Then the value is absolute. */
4461 else if (valid0 == valid1 && valid0 != 0)
4462 ret = null_pointer_node;
4463 /* Since GCC guarantees that string constants are unique in the
4464 generated code, a subtraction between two copies of the same
4465 constant string is absolute. */
4466 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4467 && valid1 && TREE_CODE (valid1) == STRING_CST
4468 && operand_equal_p (valid0, valid1, 1))
4469 ret = null_pointer_node;
4470 /* Support narrowing differences. */
4471 else
4472 ret = narrowing_initializer_constant_valid_p (value, endtype,
4473 ncache);
4474 }
4475 else
4476 /* Support narrowing differences. */
4477 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4478 if (cache)
4479 {
4480 cache[0] = value;
4481 cache[1] = ret;
4482 }
4483 return ret;
4484
4485 default:
4486 break;
4487 }
4488
4489 return NULL_TREE;
4490 }
4491
4492 /* Return nonzero if VALUE is a valid constant-valued expression
4493 for use in initializing a static variable; one that can be an
4494 element of a "constant" initializer.
4495
4496 Return null_pointer_node if the value is absolute;
4497 if it is relocatable, return the variable that determines the relocation.
4498 We assume that VALUE has been folded as much as possible;
4499 therefore, we do not need to check for such things as
4500 arithmetic-combinations of integers. */
4501 tree
4502 initializer_constant_valid_p (tree value, tree endtype)
4503 {
4504 return initializer_constant_valid_p_1 (value, endtype, NULL);
4505 }
4506 \f
4507 /* Return true if VALUE is a valid constant-valued expression
4508 for use in initializing a static bit-field; one that can be
4509 an element of a "constant" initializer. */
4510
4511 bool
4512 initializer_constant_valid_for_bitfield_p (tree value)
4513 {
4514 /* For bitfields we support integer constants or possibly nested aggregates
4515 of such. */
4516 switch (TREE_CODE (value))
4517 {
4518 case CONSTRUCTOR:
4519 {
4520 unsigned HOST_WIDE_INT idx;
4521 tree elt;
4522
4523 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4524 if (!initializer_constant_valid_for_bitfield_p (elt))
4525 return false;
4526 return true;
4527 }
4528
4529 case INTEGER_CST:
4530 case REAL_CST:
4531 return true;
4532
4533 case VIEW_CONVERT_EXPR:
4534 case NON_LVALUE_EXPR:
4535 return
4536 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4537
4538 default:
4539 break;
4540 }
4541
4542 return false;
4543 }
4544
4545 /* output_constructor outer state of relevance in recursive calls, typically
4546 for nested aggregate bitfields. */
4547
4548 typedef struct {
4549 unsigned int bit_offset; /* current position in ... */
4550 int byte; /* ... the outer byte buffer. */
4551 } oc_outer_state;
4552
4553 static unsigned HOST_WIDE_INT
4554 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int,
4555 oc_outer_state *);
4556
4557 /* Output assembler code for constant EXP, with no label.
4558 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4559 Assumes output_addressed_constants has been done on EXP already.
4560
4561 Generate at least SIZE bytes of assembler data, padding at the end
4562 with zeros if necessary. SIZE must always be specified. The returned
4563 value is the actual number of bytes of assembler data generated, which
4564 may be bigger than SIZE if the object contains a variable length field.
4565
4566 SIZE is important for structure constructors,
4567 since trailing members may have been omitted from the constructor.
4568 It is also important for initialization of arrays from string constants
4569 since the full length of the string constant might not be wanted.
4570 It is also needed for initialization of unions, where the initializer's
4571 type is just one member, and that may not be as long as the union.
4572
4573 There a case in which we would fail to output exactly SIZE bytes:
4574 for a structure constructor that wants to produce more than SIZE bytes.
4575 But such constructors will never be generated for any possible input.
4576
4577 ALIGN is the alignment of the data in bits. */
4578
4579 static unsigned HOST_WIDE_INT
4580 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align)
4581 {
4582 enum tree_code code;
4583 unsigned HOST_WIDE_INT thissize;
4584
4585 if (size == 0 || flag_syntax_only)
4586 return size;
4587
4588 /* See if we're trying to initialize a pointer in a non-default mode
4589 to the address of some declaration somewhere. If the target says
4590 the mode is valid for pointers, assume the target has a way of
4591 resolving it. */
4592 if (TREE_CODE (exp) == NOP_EXPR
4593 && POINTER_TYPE_P (TREE_TYPE (exp))
4594 && targetm.addr_space.valid_pointer_mode
4595 (TYPE_MODE (TREE_TYPE (exp)),
4596 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4597 {
4598 tree saved_type = TREE_TYPE (exp);
4599
4600 /* Peel off any intermediate conversions-to-pointer for valid
4601 pointer modes. */
4602 while (TREE_CODE (exp) == NOP_EXPR
4603 && POINTER_TYPE_P (TREE_TYPE (exp))
4604 && targetm.addr_space.valid_pointer_mode
4605 (TYPE_MODE (TREE_TYPE (exp)),
4606 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4607 exp = TREE_OPERAND (exp, 0);
4608
4609 /* If what we're left with is the address of something, we can
4610 convert the address to the final type and output it that
4611 way. */
4612 if (TREE_CODE (exp) == ADDR_EXPR)
4613 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4614 /* Likewise for constant ints. */
4615 else if (TREE_CODE (exp) == INTEGER_CST)
4616 exp = wide_int_to_tree (saved_type, exp);
4617
4618 }
4619
4620 /* Eliminate any conversions since we'll be outputting the underlying
4621 constant. */
4622 while (CONVERT_EXPR_P (exp)
4623 || TREE_CODE (exp) == NON_LVALUE_EXPR
4624 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4625 {
4626 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4627 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4628
4629 /* Make sure eliminating the conversion is really a no-op, except with
4630 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4631 union types to allow for Ada unchecked unions. */
4632 if (type_size > op_size
4633 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4634 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4635 /* Keep the conversion. */
4636 break;
4637 else
4638 exp = TREE_OPERAND (exp, 0);
4639 }
4640
4641 code = TREE_CODE (TREE_TYPE (exp));
4642 thissize = int_size_in_bytes (TREE_TYPE (exp));
4643
4644 /* Allow a constructor with no elements for any data type.
4645 This means to fill the space with zeros. */
4646 if (TREE_CODE (exp) == CONSTRUCTOR
4647 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4648 {
4649 assemble_zeros (size);
4650 return size;
4651 }
4652
4653 if (TREE_CODE (exp) == FDESC_EXPR)
4654 {
4655 #ifdef ASM_OUTPUT_FDESC
4656 HOST_WIDE_INT part = tree_to_shwi (TREE_OPERAND (exp, 1));
4657 tree decl = TREE_OPERAND (exp, 0);
4658 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4659 #else
4660 gcc_unreachable ();
4661 #endif
4662 return size;
4663 }
4664
4665 /* Now output the underlying data. If we've handling the padding, return.
4666 Otherwise, break and ensure SIZE is the size written. */
4667 switch (code)
4668 {
4669 case BOOLEAN_TYPE:
4670 case INTEGER_TYPE:
4671 case ENUMERAL_TYPE:
4672 case POINTER_TYPE:
4673 case REFERENCE_TYPE:
4674 case OFFSET_TYPE:
4675 case FIXED_POINT_TYPE:
4676 case NULLPTR_TYPE:
4677 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
4678 EXPAND_INITIALIZER),
4679 MIN (size, thissize), align, 0))
4680 error ("initializer for integer/fixed-point value is too complicated");
4681 break;
4682
4683 case REAL_TYPE:
4684 if (TREE_CODE (exp) != REAL_CST)
4685 error ("initializer for floating value is not a floating constant");
4686 else
4687 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)), align);
4688 break;
4689
4690 case COMPLEX_TYPE:
4691 output_constant (TREE_REALPART (exp), thissize / 2, align);
4692 output_constant (TREE_IMAGPART (exp), thissize / 2,
4693 min_align (align, BITS_PER_UNIT * (thissize / 2)));
4694 break;
4695
4696 case ARRAY_TYPE:
4697 case VECTOR_TYPE:
4698 switch (TREE_CODE (exp))
4699 {
4700 case CONSTRUCTOR:
4701 return output_constructor (exp, size, align, NULL);
4702 case STRING_CST:
4703 thissize
4704 = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4705 assemble_string (TREE_STRING_POINTER (exp), thissize);
4706 break;
4707 case VECTOR_CST:
4708 {
4709 enum machine_mode inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4710 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4711 int elt_size = GET_MODE_SIZE (inner);
4712 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align);
4713 thissize = elt_size;
4714 for (unsigned int i = 1; i < VECTOR_CST_NELTS (exp); i++)
4715 {
4716 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign);
4717 thissize += elt_size;
4718 }
4719 break;
4720 }
4721 default:
4722 gcc_unreachable ();
4723 }
4724 break;
4725
4726 case RECORD_TYPE:
4727 case UNION_TYPE:
4728 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4729 return output_constructor (exp, size, align, NULL);
4730
4731 case ERROR_MARK:
4732 return 0;
4733
4734 default:
4735 gcc_unreachable ();
4736 }
4737
4738 if (size > thissize)
4739 assemble_zeros (size - thissize);
4740
4741 return size;
4742 }
4743
4744 \f
4745 /* Subroutine of output_constructor, used for computing the size of
4746 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4747 type with an unspecified upper bound. */
4748
4749 static unsigned HOST_WIDE_INT
4750 array_size_for_constructor (tree val)
4751 {
4752 tree max_index;
4753 unsigned HOST_WIDE_INT cnt;
4754 tree index, value, tmp;
4755 offset_int i;
4756
4757 /* This code used to attempt to handle string constants that are not
4758 arrays of single-bytes, but nothing else does, so there's no point in
4759 doing it here. */
4760 if (TREE_CODE (val) == STRING_CST)
4761 return TREE_STRING_LENGTH (val);
4762
4763 max_index = NULL_TREE;
4764 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
4765 {
4766 if (TREE_CODE (index) == RANGE_EXPR)
4767 index = TREE_OPERAND (index, 1);
4768 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
4769 max_index = index;
4770 }
4771
4772 if (max_index == NULL_TREE)
4773 return 0;
4774
4775 /* Compute the total number of array elements. */
4776 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
4777 i = wi::to_offset (max_index) - wi::to_offset (tmp) + 1;
4778
4779 /* Multiply by the array element unit size to find number of bytes. */
4780 i *= wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
4781
4782 gcc_assert (wi::fits_uhwi_p (i));
4783 return i.to_uhwi ();
4784 }
4785
4786 /* Other datastructures + helpers for output_constructor. */
4787
4788 /* output_constructor local state to support interaction with helpers. */
4789
4790 typedef struct {
4791
4792 /* Received arguments. */
4793 tree exp; /* Constructor expression. */
4794 tree type; /* Type of constructor expression. */
4795 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */
4796 unsigned int align; /* Known initial alignment. */
4797 tree min_index; /* Lower bound if specified for an array. */
4798
4799 /* Output processing state. */
4800 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */
4801 int byte; /* Part of a bitfield byte yet to be output. */
4802 int last_relative_index; /* Implicit or explicit index of the last
4803 array element output within a bitfield. */
4804 bool byte_buffer_in_use; /* Whether BYTE is in use. */
4805
4806 /* Current element. */
4807 tree field; /* Current field decl in a record. */
4808 tree val; /* Current element value. */
4809 tree index; /* Current element index. */
4810
4811 } oc_local_state;
4812
4813 /* Helper for output_constructor. From the current LOCAL state, output a
4814 RANGE_EXPR element. */
4815
4816 static void
4817 output_constructor_array_range (oc_local_state *local)
4818 {
4819 unsigned HOST_WIDE_INT fieldsize
4820 = int_size_in_bytes (TREE_TYPE (local->type));
4821
4822 HOST_WIDE_INT lo_index
4823 = tree_to_shwi (TREE_OPERAND (local->index, 0));
4824 HOST_WIDE_INT hi_index
4825 = tree_to_shwi (TREE_OPERAND (local->index, 1));
4826 HOST_WIDE_INT index;
4827
4828 unsigned int align2
4829 = min_align (local->align, fieldsize * BITS_PER_UNIT);
4830
4831 for (index = lo_index; index <= hi_index; index++)
4832 {
4833 /* Output the element's initial value. */
4834 if (local->val == NULL_TREE)
4835 assemble_zeros (fieldsize);
4836 else
4837 fieldsize = output_constant (local->val, fieldsize, align2);
4838
4839 /* Count its size. */
4840 local->total_bytes += fieldsize;
4841 }
4842 }
4843
4844 /* Helper for output_constructor. From the current LOCAL state, output a
4845 field element that is not true bitfield or part of an outer one. */
4846
4847 static void
4848 output_constructor_regular_field (oc_local_state *local)
4849 {
4850 /* Field size and position. Since this structure is static, we know the
4851 positions are constant. */
4852 unsigned HOST_WIDE_INT fieldsize;
4853 HOST_WIDE_INT fieldpos;
4854
4855 unsigned int align2;
4856
4857 if (local->index != NULL_TREE)
4858 {
4859 /* Perform the index calculation in modulo arithmetic but
4860 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
4861 but we are using an unsigned sizetype. */
4862 unsigned prec = TYPE_PRECISION (sizetype);
4863 offset_int idx = wi::sext (wi::to_offset (local->index)
4864 - wi::to_offset (local->min_index), prec);
4865 fieldpos = (idx * wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (local->val))))
4866 .to_short_addr ();
4867 }
4868 else if (local->field != NULL_TREE)
4869 fieldpos = int_byte_position (local->field);
4870 else
4871 fieldpos = 0;
4872
4873 /* Output any buffered-up bit-fields preceding this element. */
4874 if (local->byte_buffer_in_use)
4875 {
4876 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4877 local->total_bytes++;
4878 local->byte_buffer_in_use = false;
4879 }
4880
4881 /* Advance to offset of this element.
4882 Note no alignment needed in an array, since that is guaranteed
4883 if each element has the proper size. */
4884 if ((local->field != NULL_TREE || local->index != NULL_TREE)
4885 && fieldpos > local->total_bytes)
4886 {
4887 assemble_zeros (fieldpos - local->total_bytes);
4888 local->total_bytes = fieldpos;
4889 }
4890
4891 /* Find the alignment of this element. */
4892 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
4893
4894 /* Determine size this element should occupy. */
4895 if (local->field)
4896 {
4897 fieldsize = 0;
4898
4899 /* If this is an array with an unspecified upper bound,
4900 the initializer determines the size. */
4901 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
4902 but we cannot do this until the deprecated support for
4903 initializing zero-length array members is removed. */
4904 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
4905 && TYPE_DOMAIN (TREE_TYPE (local->field))
4906 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field))))
4907 {
4908 fieldsize = array_size_for_constructor (local->val);
4909 /* Given a non-empty initialization, this field had
4910 better be last. */
4911 gcc_assert (!fieldsize || !DECL_CHAIN (local->field));
4912 }
4913 else
4914 fieldsize = tree_to_uhwi (DECL_SIZE_UNIT (local->field));
4915 }
4916 else
4917 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
4918
4919 /* Output the element's initial value. */
4920 if (local->val == NULL_TREE)
4921 assemble_zeros (fieldsize);
4922 else
4923 fieldsize = output_constant (local->val, fieldsize, align2);
4924
4925 /* Count its size. */
4926 local->total_bytes += fieldsize;
4927 }
4928
4929 /* Helper for output_constructor. From the LOCAL state, output an element
4930 that is a true bitfield or part of an outer one. BIT_OFFSET is the offset
4931 from the start of a possibly ongoing outer byte buffer. */
4932
4933 static void
4934 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
4935 {
4936 /* Bit size of this element. */
4937 HOST_WIDE_INT ebitsize
4938 = (local->field
4939 ? tree_to_uhwi (DECL_SIZE (local->field))
4940 : tree_to_uhwi (TYPE_SIZE (TREE_TYPE (local->type))));
4941
4942 /* Relative index of this element if this is an array component. */
4943 HOST_WIDE_INT relative_index
4944 = (!local->field
4945 ? (local->index
4946 ? (tree_to_shwi (local->index)
4947 - tree_to_shwi (local->min_index))
4948 : local->last_relative_index + 1)
4949 : 0);
4950
4951 /* Bit position of this element from the start of the containing
4952 constructor. */
4953 HOST_WIDE_INT constructor_relative_ebitpos
4954 = (local->field
4955 ? int_bit_position (local->field)
4956 : ebitsize * relative_index);
4957
4958 /* Bit position of this element from the start of a possibly ongoing
4959 outer byte buffer. */
4960 HOST_WIDE_INT byte_relative_ebitpos
4961 = bit_offset + constructor_relative_ebitpos;
4962
4963 /* From the start of a possibly ongoing outer byte buffer, offsets to
4964 the first bit of this element and to the first bit past the end of
4965 this element. */
4966 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
4967 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
4968
4969 local->last_relative_index = relative_index;
4970
4971 if (local->val == NULL_TREE)
4972 local->val = integer_zero_node;
4973
4974 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
4975 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
4976 local->val = TREE_OPERAND (local->val, 0);
4977
4978 if (TREE_CODE (local->val) != INTEGER_CST
4979 && TREE_CODE (local->val) != CONSTRUCTOR)
4980 {
4981 error ("invalid initial value for member %qE", DECL_NAME (local->field));
4982 return;
4983 }
4984
4985 /* If this field does not start in this (or next) byte, skip some bytes. */
4986 if (next_offset / BITS_PER_UNIT != local->total_bytes)
4987 {
4988 /* Output remnant of any bit field in previous bytes. */
4989 if (local->byte_buffer_in_use)
4990 {
4991 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4992 local->total_bytes++;
4993 local->byte_buffer_in_use = false;
4994 }
4995
4996 /* If still not at proper byte, advance to there. */
4997 if (next_offset / BITS_PER_UNIT != local->total_bytes)
4998 {
4999 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
5000 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
5001 local->total_bytes = next_offset / BITS_PER_UNIT;
5002 }
5003 }
5004
5005 /* Set up the buffer if necessary. */
5006 if (!local->byte_buffer_in_use)
5007 {
5008 local->byte = 0;
5009 if (ebitsize > 0)
5010 local->byte_buffer_in_use = true;
5011 }
5012
5013 /* If this is nested constructor, recurse passing the bit offset and the
5014 pending data, then retrieve the new pending data afterwards. */
5015 if (TREE_CODE (local->val) == CONSTRUCTOR)
5016 {
5017 oc_outer_state temp_state;
5018 temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5019 temp_state.byte = local->byte;
5020 local->total_bytes
5021 += output_constructor (local->val, 0, 0, &temp_state);
5022 local->byte = temp_state.byte;
5023 return;
5024 }
5025
5026 /* Otherwise, we must split the element into pieces that fall within
5027 separate bytes, and combine each byte with previous or following
5028 bit-fields. */
5029 while (next_offset < end_offset)
5030 {
5031 int this_time;
5032 int shift;
5033 HOST_WIDE_INT value;
5034 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5035 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5036
5037 /* Advance from byte to byte within this element when necessary. */
5038 while (next_byte != local->total_bytes)
5039 {
5040 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5041 local->total_bytes++;
5042 local->byte = 0;
5043 }
5044
5045 /* Number of bits we can process at once (all part of the same byte). */
5046 this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5047 if (BYTES_BIG_ENDIAN)
5048 {
5049 /* On big-endian machine, take the most significant bits (of the
5050 bits that are significant) first and put them into bytes from
5051 the most significant end. */
5052 shift = end_offset - next_offset - this_time;
5053
5054 /* Don't try to take a bunch of bits that cross
5055 the word boundary in the INTEGER_CST. We can
5056 only select bits from one element. */
5057 if ((shift / HOST_BITS_PER_WIDE_INT)
5058 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5059 {
5060 const int end = shift + this_time - 1;
5061 shift = end & -HOST_BITS_PER_WIDE_INT;
5062 this_time = end - shift + 1;
5063 }
5064
5065 /* Now get the bits from the appropriate constant word. */
5066 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5067 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5068
5069 /* Get the result. This works only when:
5070 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5071 local->byte |= (((value >> shift)
5072 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5073 << (BITS_PER_UNIT - this_time - next_bit));
5074 }
5075 else
5076 {
5077 /* On little-endian machines, take the least significant bits of
5078 the value first and pack them starting at the least significant
5079 bits of the bytes. */
5080 shift = next_offset - byte_relative_ebitpos;
5081
5082 /* Don't try to take a bunch of bits that cross
5083 the word boundary in the INTEGER_CST. We can
5084 only select bits from one element. */
5085 if ((shift / HOST_BITS_PER_WIDE_INT)
5086 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5087 this_time
5088 = HOST_BITS_PER_WIDE_INT - (shift & (HOST_BITS_PER_WIDE_INT - 1));
5089
5090 /* Now get the bits from the appropriate constant word. */
5091 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5092 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5093
5094 /* Get the result. This works only when:
5095 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5096 local->byte |= (((value >> shift)
5097 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5098 << next_bit);
5099 }
5100
5101 next_offset += this_time;
5102 local->byte_buffer_in_use = true;
5103 }
5104 }
5105
5106 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5107 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5108 caller output state of relevance in recursive invocations. */
5109
5110 static unsigned HOST_WIDE_INT
5111 output_constructor (tree exp, unsigned HOST_WIDE_INT size,
5112 unsigned int align, oc_outer_state *outer)
5113 {
5114 unsigned HOST_WIDE_INT cnt;
5115 constructor_elt *ce;
5116
5117 oc_local_state local;
5118
5119 /* Setup our local state to communicate with helpers. */
5120 local.exp = exp;
5121 local.type = TREE_TYPE (exp);
5122 local.size = size;
5123 local.align = align;
5124 if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5125 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5126 else
5127 local.min_index = NULL_TREE;
5128
5129 local.total_bytes = 0;
5130 local.byte_buffer_in_use = outer != NULL;
5131 local.byte = outer ? outer->byte : 0;
5132 local.last_relative_index = -1;
5133
5134 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5135
5136 /* As CE goes through the elements of the constant, FIELD goes through the
5137 structure fields if the constant is a structure. If the constant is a
5138 union, we override this by getting the field from the TREE_LIST element.
5139 But the constant could also be an array. Then FIELD is zero.
5140
5141 There is always a maximum of one element in the chain LINK for unions
5142 (even if the initializer in a source program incorrectly contains
5143 more one). */
5144
5145 if (TREE_CODE (local.type) == RECORD_TYPE)
5146 local.field = TYPE_FIELDS (local.type);
5147 else
5148 local.field = NULL_TREE;
5149
5150 for (cnt = 0;
5151 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5152 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5153 {
5154 local.val = ce->value;
5155 local.index = NULL_TREE;
5156
5157 /* The element in a union constructor specifies the proper field
5158 or index. */
5159 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5160 local.field = ce->index;
5161
5162 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5163 local.index = ce->index;
5164
5165 if (local.field && flag_verbose_asm)
5166 fprintf (asm_out_file, "%s %s:\n",
5167 ASM_COMMENT_START,
5168 DECL_NAME (local.field)
5169 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5170 : "<anonymous>");
5171
5172 /* Eliminate the marker that makes a cast not be an lvalue. */
5173 if (local.val != NULL_TREE)
5174 STRIP_NOPS (local.val);
5175
5176 /* Output the current element, using the appropriate helper ... */
5177
5178 /* For an array slice not part of an outer bitfield. */
5179 if (!outer
5180 && local.index != NULL_TREE
5181 && TREE_CODE (local.index) == RANGE_EXPR)
5182 output_constructor_array_range (&local);
5183
5184 /* For a field that is neither a true bitfield nor part of an outer one,
5185 known to be at least byte aligned and multiple-of-bytes long. */
5186 else if (!outer
5187 && (local.field == NULL_TREE
5188 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5189 output_constructor_regular_field (&local);
5190
5191 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5192 supported for scalar fields, so we may need to convert first. */
5193 else
5194 {
5195 if (TREE_CODE (local.val) == REAL_CST)
5196 local.val
5197 = fold_unary (VIEW_CONVERT_EXPR,
5198 build_nonstandard_integer_type
5199 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5200 local.val);
5201 output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5202 }
5203 }
5204
5205 /* If we are not at toplevel, save the pending data for our caller.
5206 Otherwise output the pending data and padding zeros as needed. */
5207 if (outer)
5208 outer->byte = local.byte;
5209 else
5210 {
5211 if (local.byte_buffer_in_use)
5212 {
5213 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5214 local.total_bytes++;
5215 }
5216
5217 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5218 {
5219 assemble_zeros (local.size - local.total_bytes);
5220 local.total_bytes = local.size;
5221 }
5222 }
5223
5224 return local.total_bytes;
5225 }
5226
5227 /* Mark DECL as weak. */
5228
5229 static void
5230 mark_weak (tree decl)
5231 {
5232 DECL_WEAK (decl) = 1;
5233
5234 if (DECL_RTL_SET_P (decl)
5235 && MEM_P (DECL_RTL (decl))
5236 && XEXP (DECL_RTL (decl), 0)
5237 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5238 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5239 }
5240
5241 /* Merge weak status between NEWDECL and OLDDECL. */
5242
5243 void
5244 merge_weak (tree newdecl, tree olddecl)
5245 {
5246 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5247 {
5248 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5249 {
5250 tree *pwd;
5251 /* We put the NEWDECL on the weak_decls list at some point
5252 and OLDDECL as well. Keep just OLDDECL on the list. */
5253 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5254 if (TREE_VALUE (*pwd) == newdecl)
5255 {
5256 *pwd = TREE_CHAIN (*pwd);
5257 break;
5258 }
5259 }
5260 return;
5261 }
5262
5263 if (DECL_WEAK (newdecl))
5264 {
5265 tree wd;
5266
5267 /* NEWDECL is weak, but OLDDECL is not. */
5268
5269 /* If we already output the OLDDECL, we're in trouble; we can't
5270 go back and make it weak. This should never happen in
5271 unit-at-a-time compilation. */
5272 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5273
5274 /* If we've already generated rtl referencing OLDDECL, we may
5275 have done so in a way that will not function properly with
5276 a weak symbol. Again in unit-at-a-time this should be
5277 impossible. */
5278 gcc_assert (!TREE_USED (olddecl)
5279 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5280
5281 if (TARGET_SUPPORTS_WEAK)
5282 {
5283 /* We put the NEWDECL on the weak_decls list at some point.
5284 Replace it with the OLDDECL. */
5285 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5286 if (TREE_VALUE (wd) == newdecl)
5287 {
5288 TREE_VALUE (wd) = olddecl;
5289 break;
5290 }
5291 /* We may not find the entry on the list. If NEWDECL is a
5292 weak alias, then we will have already called
5293 globalize_decl to remove the entry; in that case, we do
5294 not need to do anything. */
5295 }
5296
5297 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5298 mark_weak (olddecl);
5299 }
5300 else
5301 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5302 weak. Just update NEWDECL to indicate that it's weak too. */
5303 mark_weak (newdecl);
5304 }
5305
5306 /* Declare DECL to be a weak symbol. */
5307
5308 void
5309 declare_weak (tree decl)
5310 {
5311 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5312 if (! TREE_PUBLIC (decl))
5313 error ("weak declaration of %q+D must be public", decl);
5314 else if (!TARGET_SUPPORTS_WEAK)
5315 warning (0, "weak declaration of %q+D not supported", decl);
5316
5317 mark_weak (decl);
5318 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5319 DECL_ATTRIBUTES (decl)
5320 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5321 }
5322
5323 static void
5324 weak_finish_1 (tree decl)
5325 {
5326 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5327 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5328 #endif
5329
5330 if (! TREE_USED (decl))
5331 return;
5332
5333 #ifdef ASM_WEAKEN_DECL
5334 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5335 #else
5336 #ifdef ASM_WEAKEN_LABEL
5337 ASM_WEAKEN_LABEL (asm_out_file, name);
5338 #else
5339 #ifdef ASM_OUTPUT_WEAK_ALIAS
5340 {
5341 static bool warn_once = 0;
5342 if (! warn_once)
5343 {
5344 warning (0, "only weak aliases are supported in this configuration");
5345 warn_once = 1;
5346 }
5347 return;
5348 }
5349 #endif
5350 #endif
5351 #endif
5352 }
5353
5354 /* Fiven an assembly name, find the decl it is associated with. */
5355 static tree
5356 find_decl (tree target)
5357 {
5358 symtab_node *node = symtab_node::get_for_asmname (target);
5359 if (node)
5360 return node->decl;
5361 return NULL_TREE;
5362 }
5363
5364 /* This TREE_LIST contains weakref targets. */
5365
5366 static GTY(()) tree weakref_targets;
5367
5368 /* Emit any pending weak declarations. */
5369
5370 void
5371 weak_finish (void)
5372 {
5373 tree t;
5374
5375 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5376 {
5377 tree alias_decl = TREE_PURPOSE (t);
5378 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5379
5380 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5381 /* Remove alias_decl from the weak list, but leave entries for
5382 the target alone. */
5383 target = NULL_TREE;
5384 #ifndef ASM_OUTPUT_WEAKREF
5385 else if (! TREE_SYMBOL_REFERENCED (target))
5386 {
5387 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5388 defined, otherwise we and weak_finish_1 would use
5389 different macros. */
5390 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5391 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5392 # else
5393 tree decl = find_decl (target);
5394
5395 if (! decl)
5396 {
5397 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5398 TREE_CODE (alias_decl), target,
5399 TREE_TYPE (alias_decl));
5400
5401 DECL_EXTERNAL (decl) = 1;
5402 TREE_PUBLIC (decl) = 1;
5403 DECL_ARTIFICIAL (decl) = 1;
5404 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5405 TREE_USED (decl) = 1;
5406 }
5407
5408 weak_finish_1 (decl);
5409 # endif
5410 }
5411 #endif
5412
5413 {
5414 tree *p;
5415 tree t2;
5416
5417 /* Remove the alias and the target from the pending weak list
5418 so that we do not emit any .weak directives for the former,
5419 nor multiple .weak directives for the latter. */
5420 for (p = &weak_decls; (t2 = *p) ; )
5421 {
5422 if (TREE_VALUE (t2) == alias_decl
5423 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5424 *p = TREE_CHAIN (t2);
5425 else
5426 p = &TREE_CHAIN (t2);
5427 }
5428
5429 /* Remove other weakrefs to the same target, to speed things up. */
5430 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5431 {
5432 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5433 *p = TREE_CHAIN (t2);
5434 else
5435 p = &TREE_CHAIN (t2);
5436 }
5437 }
5438 }
5439
5440 for (t = weak_decls; t; t = TREE_CHAIN (t))
5441 {
5442 tree decl = TREE_VALUE (t);
5443
5444 weak_finish_1 (decl);
5445 }
5446 }
5447
5448 /* Emit the assembly bits to indicate that DECL is globally visible. */
5449
5450 static void
5451 globalize_decl (tree decl)
5452 {
5453
5454 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5455 if (DECL_WEAK (decl))
5456 {
5457 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5458 tree *p, t;
5459
5460 #ifdef ASM_WEAKEN_DECL
5461 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5462 #else
5463 ASM_WEAKEN_LABEL (asm_out_file, name);
5464 #endif
5465
5466 /* Remove this function from the pending weak list so that
5467 we do not emit multiple .weak directives for it. */
5468 for (p = &weak_decls; (t = *p) ; )
5469 {
5470 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5471 *p = TREE_CHAIN (t);
5472 else
5473 p = &TREE_CHAIN (t);
5474 }
5475
5476 /* Remove weakrefs to the same target from the pending weakref
5477 list, for the same reason. */
5478 for (p = &weakref_targets; (t = *p) ; )
5479 {
5480 if (DECL_ASSEMBLER_NAME (decl)
5481 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5482 *p = TREE_CHAIN (t);
5483 else
5484 p = &TREE_CHAIN (t);
5485 }
5486
5487 return;
5488 }
5489 #endif
5490
5491 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5492 }
5493
5494 vec<alias_pair, va_gc> *alias_pairs;
5495
5496 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5497 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5498 tree node is DECL to have the value of the tree node TARGET. */
5499
5500 void
5501 do_assemble_alias (tree decl, tree target)
5502 {
5503 /* Emulated TLS had better not get this var. */
5504 gcc_assert (!(!targetm.have_tls
5505 && TREE_CODE (decl) == VAR_DECL
5506 && DECL_THREAD_LOCAL_P (decl)));
5507
5508 if (TREE_ASM_WRITTEN (decl))
5509 return;
5510
5511 /* We must force creation of DECL_RTL for debug info generation, even though
5512 we don't use it here. */
5513 make_decl_rtl (decl);
5514
5515 TREE_ASM_WRITTEN (decl) = 1;
5516 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5517
5518 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5519 {
5520 ultimate_transparent_alias_target (&target);
5521
5522 if (!TREE_SYMBOL_REFERENCED (target))
5523 weakref_targets = tree_cons (decl, target, weakref_targets);
5524
5525 #ifdef ASM_OUTPUT_WEAKREF
5526 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5527 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5528 IDENTIFIER_POINTER (target));
5529 #else
5530 if (!TARGET_SUPPORTS_WEAK)
5531 {
5532 error_at (DECL_SOURCE_LOCATION (decl),
5533 "weakref is not supported in this configuration");
5534 return;
5535 }
5536 #endif
5537 return;
5538 }
5539
5540 #ifdef ASM_OUTPUT_DEF
5541 /* Make name accessible from other files, if appropriate. */
5542
5543 if (TREE_PUBLIC (decl))
5544 {
5545 globalize_decl (decl);
5546 maybe_assemble_visibility (decl);
5547 }
5548 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5549 {
5550 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5551 if (targetm.has_ifunc_p ())
5552 ASM_OUTPUT_TYPE_DIRECTIVE
5553 (asm_out_file, IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5554 IFUNC_ASM_TYPE);
5555 else
5556 #endif
5557 error_at (DECL_SOURCE_LOCATION (decl),
5558 "ifunc is not supported on this target");
5559 }
5560
5561 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5562 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5563 # else
5564 ASM_OUTPUT_DEF (asm_out_file,
5565 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5566 IDENTIFIER_POINTER (target));
5567 # endif
5568 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5569 {
5570 const char *name;
5571 tree *p, t;
5572
5573 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5574 # ifdef ASM_WEAKEN_DECL
5575 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5576 # else
5577 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5578 # endif
5579 /* Remove this function from the pending weak list so that
5580 we do not emit multiple .weak directives for it. */
5581 for (p = &weak_decls; (t = *p) ; )
5582 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5583 *p = TREE_CHAIN (t);
5584 else
5585 p = &TREE_CHAIN (t);
5586
5587 /* Remove weakrefs to the same target from the pending weakref
5588 list, for the same reason. */
5589 for (p = &weakref_targets; (t = *p) ; )
5590 {
5591 if (DECL_ASSEMBLER_NAME (decl)
5592 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5593 *p = TREE_CHAIN (t);
5594 else
5595 p = &TREE_CHAIN (t);
5596 }
5597 }
5598 #endif
5599 }
5600
5601 /* Emit an assembler directive to make the symbol for DECL an alias to
5602 the symbol for TARGET. */
5603
5604 void
5605 assemble_alias (tree decl, tree target)
5606 {
5607 tree target_decl;
5608
5609 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5610 {
5611 tree alias = DECL_ASSEMBLER_NAME (decl);
5612
5613 ultimate_transparent_alias_target (&target);
5614
5615 if (alias == target)
5616 error ("weakref %q+D ultimately targets itself", decl);
5617 if (TREE_PUBLIC (decl))
5618 error ("weakref %q+D must have static linkage", decl);
5619 }
5620 else
5621 {
5622 #if !defined (ASM_OUTPUT_DEF)
5623 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5624 error_at (DECL_SOURCE_LOCATION (decl),
5625 "alias definitions not supported in this configuration");
5626 TREE_ASM_WRITTEN (decl) = 1;
5627 return;
5628 # else
5629 if (!DECL_WEAK (decl))
5630 {
5631 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5632 error_at (DECL_SOURCE_LOCATION (decl),
5633 "ifunc is not supported in this configuration");
5634 else
5635 error_at (DECL_SOURCE_LOCATION (decl),
5636 "only weak aliases are supported in this configuration");
5637 TREE_ASM_WRITTEN (decl) = 1;
5638 return;
5639 }
5640 # endif
5641 #endif
5642 }
5643 TREE_USED (decl) = 1;
5644
5645 /* Allow aliases to aliases. */
5646 if (TREE_CODE (decl) == FUNCTION_DECL)
5647 cgraph_node::get_create (decl)->alias = true;
5648 else
5649 varpool_node::get_create (decl)->alias = true;
5650
5651 /* If the target has already been emitted, we don't have to queue the
5652 alias. This saves a tad of memory. */
5653 if (symtab->global_info_ready)
5654 target_decl = find_decl (target);
5655 else
5656 target_decl= NULL;
5657 if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5658 || symtab->state >= EXPANSION)
5659 do_assemble_alias (decl, target);
5660 else
5661 {
5662 alias_pair p = {decl, target};
5663 vec_safe_push (alias_pairs, p);
5664 }
5665 }
5666
5667 /* Record and output a table of translations from original function
5668 to its transaction aware clone. Note that tm_pure functions are
5669 considered to be their own clone. */
5670
5671 static GTY((if_marked ("tree_map_marked_p"), param_is (struct tree_map)))
5672 htab_t tm_clone_hash;
5673
5674 void
5675 record_tm_clone_pair (tree o, tree n)
5676 {
5677 struct tree_map **slot, *h;
5678
5679 if (tm_clone_hash == NULL)
5680 tm_clone_hash = htab_create_ggc (32, tree_map_hash, tree_map_eq, 0);
5681
5682 h = ggc_alloc<tree_map> ();
5683 h->hash = htab_hash_pointer (o);
5684 h->base.from = o;
5685 h->to = n;
5686
5687 slot = (struct tree_map **)
5688 htab_find_slot_with_hash (tm_clone_hash, h, h->hash, INSERT);
5689 *slot = h;
5690 }
5691
5692 tree
5693 get_tm_clone_pair (tree o)
5694 {
5695 if (tm_clone_hash)
5696 {
5697 struct tree_map *h, in;
5698
5699 in.base.from = o;
5700 in.hash = htab_hash_pointer (o);
5701 h = (struct tree_map *) htab_find_with_hash (tm_clone_hash,
5702 &in, in.hash);
5703 if (h)
5704 return h->to;
5705 }
5706 return NULL_TREE;
5707 }
5708
5709 typedef struct tm_alias_pair
5710 {
5711 unsigned int uid;
5712 tree from;
5713 tree to;
5714 } tm_alias_pair;
5715
5716
5717 /* Helper function for finish_tm_clone_pairs. Dump a hash table entry
5718 into a VEC in INFO. */
5719
5720 static int
5721 dump_tm_clone_to_vec (void **slot, void *info)
5722 {
5723 struct tree_map *map = (struct tree_map *) *slot;
5724 vec<tm_alias_pair> *tm_alias_pairs = (vec<tm_alias_pair> *) info;
5725 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
5726 tm_alias_pairs->safe_push (p);
5727 return 1;
5728 }
5729
5730 /* Dump the actual pairs to the .tm_clone_table section. */
5731
5732 static void
5733 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
5734 {
5735 unsigned i;
5736 tm_alias_pair *p;
5737 bool switched = false;
5738
5739 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
5740 {
5741 tree src = p->from;
5742 tree dst = p->to;
5743 struct cgraph_node *src_n = cgraph_node::get (src);
5744 struct cgraph_node *dst_n = cgraph_node::get (dst);
5745
5746 /* The function ipa_tm_create_version() marks the clone as needed if
5747 the original function was needed. But we also mark the clone as
5748 needed if we ever called the clone indirectly through
5749 TM_GETTMCLONE. If neither of these are true, we didn't generate
5750 a clone, and we didn't call it indirectly... no sense keeping it
5751 in the clone table. */
5752 if (!dst_n || !dst_n->definition)
5753 continue;
5754
5755 /* This covers the case where we have optimized the original
5756 function away, and only access the transactional clone. */
5757 if (!src_n || !src_n->definition)
5758 continue;
5759
5760 if (!switched)
5761 {
5762 switch_to_section (targetm.asm_out.tm_clone_table_section ());
5763 assemble_align (POINTER_SIZE);
5764 switched = true;
5765 }
5766
5767 assemble_integer (XEXP (DECL_RTL (src), 0),
5768 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
5769 assemble_integer (XEXP (DECL_RTL (dst), 0),
5770 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
5771 }
5772 }
5773
5774 /* Provide a default for the tm_clone_table section. */
5775
5776 section *
5777 default_clone_table_section (void)
5778 {
5779 return get_named_section (NULL, ".tm_clone_table", 3);
5780 }
5781
5782 /* Helper comparison function for qsorting by the DECL_UID stored in
5783 alias_pair->emitted_diags. */
5784
5785 static int
5786 tm_alias_pair_cmp (const void *x, const void *y)
5787 {
5788 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
5789 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
5790 if (p1->uid < p2->uid)
5791 return -1;
5792 if (p1->uid > p2->uid)
5793 return 1;
5794 return 0;
5795 }
5796
5797 void
5798 finish_tm_clone_pairs (void)
5799 {
5800 vec<tm_alias_pair> tm_alias_pairs = vNULL;
5801
5802 if (tm_clone_hash == NULL)
5803 return;
5804
5805 /* We need a determenistic order for the .tm_clone_table, otherwise
5806 we will get bootstrap comparison failures, so dump the hash table
5807 to a vector, sort it, and dump the vector. */
5808
5809 /* Dump the hashtable to a vector. */
5810 htab_traverse_noresize (tm_clone_hash, dump_tm_clone_to_vec,
5811 (void *) &tm_alias_pairs);
5812 /* Sort it. */
5813 tm_alias_pairs.qsort (tm_alias_pair_cmp);
5814
5815 /* Dump it. */
5816 dump_tm_clone_pairs (tm_alias_pairs);
5817
5818 htab_delete (tm_clone_hash);
5819 tm_clone_hash = NULL;
5820 tm_alias_pairs.release ();
5821 }
5822
5823
5824 /* Emit an assembler directive to set symbol for DECL visibility to
5825 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
5826
5827 void
5828 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
5829 int vis ATTRIBUTE_UNUSED)
5830 {
5831 #ifdef HAVE_GAS_HIDDEN
5832 static const char * const visibility_types[] = {
5833 NULL, "protected", "hidden", "internal"
5834 };
5835
5836 const char *name, *type;
5837
5838 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5839 type = visibility_types[vis];
5840
5841 fprintf (asm_out_file, "\t.%s\t", type);
5842 assemble_name (asm_out_file, name);
5843 fprintf (asm_out_file, "\n");
5844 #else
5845 if (!DECL_ARTIFICIAL (decl))
5846 warning (OPT_Wattributes, "visibility attribute not supported "
5847 "in this configuration; ignored");
5848 #endif
5849 }
5850
5851 /* A helper function to call assemble_visibility when needed for a decl. */
5852
5853 int
5854 maybe_assemble_visibility (tree decl)
5855 {
5856 enum symbol_visibility vis = DECL_VISIBILITY (decl);
5857
5858 if (vis != VISIBILITY_DEFAULT)
5859 {
5860 targetm.asm_out.assemble_visibility (decl, vis);
5861 return 1;
5862 }
5863 else
5864 return 0;
5865 }
5866
5867 /* Returns 1 if the target configuration supports defining public symbols
5868 so that one of them will be chosen at link time instead of generating a
5869 multiply-defined symbol error, whether through the use of weak symbols or
5870 a target-specific mechanism for having duplicates discarded. */
5871
5872 int
5873 supports_one_only (void)
5874 {
5875 if (SUPPORTS_ONE_ONLY)
5876 return 1;
5877 return TARGET_SUPPORTS_WEAK;
5878 }
5879
5880 /* Set up DECL as a public symbol that can be defined in multiple
5881 translation units without generating a linker error. */
5882
5883 void
5884 make_decl_one_only (tree decl, tree comdat_group)
5885 {
5886 struct symtab_node *symbol;
5887 gcc_assert (TREE_CODE (decl) == VAR_DECL
5888 || TREE_CODE (decl) == FUNCTION_DECL);
5889
5890 TREE_PUBLIC (decl) = 1;
5891
5892 if (TREE_CODE (decl) == VAR_DECL)
5893 symbol = varpool_node::get_create (decl);
5894 else
5895 symbol = cgraph_node::get_create (decl);
5896
5897 if (SUPPORTS_ONE_ONLY)
5898 {
5899 #ifdef MAKE_DECL_ONE_ONLY
5900 MAKE_DECL_ONE_ONLY (decl);
5901 #endif
5902 symbol->set_comdat_group (comdat_group);
5903 }
5904 else if (TREE_CODE (decl) == VAR_DECL
5905 && (DECL_INITIAL (decl) == 0
5906 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
5907 DECL_COMMON (decl) = 1;
5908 else
5909 {
5910 gcc_assert (TARGET_SUPPORTS_WEAK);
5911 DECL_WEAK (decl) = 1;
5912 }
5913 }
5914
5915 void
5916 init_varasm_once (void)
5917 {
5918 section_htab = htab_create_ggc (31, section_entry_hash,
5919 section_entry_eq, NULL);
5920 object_block_htab = htab_create_ggc (31, object_block_entry_hash,
5921 object_block_entry_eq, NULL);
5922 const_desc_htab = htab_create_ggc (1009, const_desc_hash,
5923 const_desc_eq, NULL);
5924
5925 const_alias_set = new_alias_set ();
5926 shared_constant_pool = create_constant_pool ();
5927
5928 #ifdef TEXT_SECTION_ASM_OP
5929 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
5930 TEXT_SECTION_ASM_OP);
5931 #endif
5932
5933 #ifdef DATA_SECTION_ASM_OP
5934 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5935 DATA_SECTION_ASM_OP);
5936 #endif
5937
5938 #ifdef SDATA_SECTION_ASM_OP
5939 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5940 SDATA_SECTION_ASM_OP);
5941 #endif
5942
5943 #ifdef READONLY_DATA_SECTION_ASM_OP
5944 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
5945 READONLY_DATA_SECTION_ASM_OP);
5946 #endif
5947
5948 #ifdef CTORS_SECTION_ASM_OP
5949 ctors_section = get_unnamed_section (0, output_section_asm_op,
5950 CTORS_SECTION_ASM_OP);
5951 #endif
5952
5953 #ifdef DTORS_SECTION_ASM_OP
5954 dtors_section = get_unnamed_section (0, output_section_asm_op,
5955 DTORS_SECTION_ASM_OP);
5956 #endif
5957
5958 #ifdef BSS_SECTION_ASM_OP
5959 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5960 output_section_asm_op,
5961 BSS_SECTION_ASM_OP);
5962 #endif
5963
5964 #ifdef SBSS_SECTION_ASM_OP
5965 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5966 output_section_asm_op,
5967 SBSS_SECTION_ASM_OP);
5968 #endif
5969
5970 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5971 | SECTION_COMMON, emit_tls_common);
5972 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5973 | SECTION_COMMON, emit_local);
5974 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5975 | SECTION_COMMON, emit_common);
5976
5977 #if defined ASM_OUTPUT_ALIGNED_BSS
5978 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
5979 emit_bss);
5980 #endif
5981
5982 targetm.asm_out.init_sections ();
5983
5984 if (readonly_data_section == NULL)
5985 readonly_data_section = text_section;
5986
5987 #ifdef ASM_OUTPUT_EXTERNAL
5988 pending_assemble_externals_set = new hash_set<tree>;
5989 #endif
5990 }
5991
5992 enum tls_model
5993 decl_default_tls_model (const_tree decl)
5994 {
5995 enum tls_model kind;
5996 bool is_local;
5997
5998 is_local = targetm.binds_local_p (decl);
5999 if (!flag_shlib)
6000 {
6001 if (is_local)
6002 kind = TLS_MODEL_LOCAL_EXEC;
6003 else
6004 kind = TLS_MODEL_INITIAL_EXEC;
6005 }
6006
6007 /* Local dynamic is inefficient when we're not combining the
6008 parts of the address. */
6009 else if (optimize && is_local)
6010 kind = TLS_MODEL_LOCAL_DYNAMIC;
6011 else
6012 kind = TLS_MODEL_GLOBAL_DYNAMIC;
6013 if (kind < flag_tls_default)
6014 kind = flag_tls_default;
6015
6016 return kind;
6017 }
6018
6019 /* Select a set of attributes for section NAME based on the properties
6020 of DECL and whether or not RELOC indicates that DECL's initializer
6021 might contain runtime relocations.
6022
6023 We make the section read-only and executable for a function decl,
6024 read-only for a const data decl, and writable for a non-const data decl. */
6025
6026 unsigned int
6027 default_section_type_flags (tree decl, const char *name, int reloc)
6028 {
6029 unsigned int flags;
6030
6031 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6032 flags = SECTION_CODE;
6033 else if (decl)
6034 {
6035 enum section_category category
6036 = categorize_decl_for_section (decl, reloc);
6037 if (decl_readonly_section_1 (category))
6038 flags = 0;
6039 else if (category == SECCAT_DATA_REL_RO
6040 || category == SECCAT_DATA_REL_RO_LOCAL)
6041 flags = SECTION_WRITE | SECTION_RELRO;
6042 else
6043 flags = SECTION_WRITE;
6044 }
6045 else
6046 {
6047 flags = SECTION_WRITE;
6048 if (strcmp (name, ".data.rel.ro") == 0
6049 || strcmp (name, ".data.rel.ro.local") == 0)
6050 flags |= SECTION_RELRO;
6051 }
6052
6053 if (decl && DECL_P (decl) && DECL_COMDAT_GROUP (decl))
6054 flags |= SECTION_LINKONCE;
6055
6056 if (strcmp (name, ".vtable_map_vars") == 0)
6057 flags |= SECTION_LINKONCE;
6058
6059 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6060 flags |= SECTION_TLS | SECTION_WRITE;
6061
6062 if (strcmp (name, ".bss") == 0
6063 || strncmp (name, ".bss.", 5) == 0
6064 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6065 || strcmp (name, ".sbss") == 0
6066 || strncmp (name, ".sbss.", 6) == 0
6067 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6068 flags |= SECTION_BSS;
6069
6070 if (strcmp (name, ".tdata") == 0
6071 || strncmp (name, ".tdata.", 7) == 0
6072 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6073 flags |= SECTION_TLS;
6074
6075 if (strcmp (name, ".tbss") == 0
6076 || strncmp (name, ".tbss.", 6) == 0
6077 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6078 flags |= SECTION_TLS | SECTION_BSS;
6079
6080 /* These three sections have special ELF types. They are neither
6081 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
6082 want to print a section type (@progbits or @nobits). If someone
6083 is silly enough to emit code or TLS variables to one of these
6084 sections, then don't handle them specially. */
6085 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6086 && (strcmp (name, ".init_array") == 0
6087 || strcmp (name, ".fini_array") == 0
6088 || strcmp (name, ".preinit_array") == 0))
6089 flags |= SECTION_NOTYPE;
6090
6091 return flags;
6092 }
6093
6094 /* Return true if the target supports some form of global BSS,
6095 either through bss_noswitch_section, or by selecting a BSS
6096 section in TARGET_ASM_SELECT_SECTION. */
6097
6098 bool
6099 have_global_bss_p (void)
6100 {
6101 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6102 }
6103
6104 /* Output assembly to switch to section NAME with attribute FLAGS.
6105 Four variants for common object file formats. */
6106
6107 void
6108 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6109 unsigned int flags ATTRIBUTE_UNUSED,
6110 tree decl ATTRIBUTE_UNUSED)
6111 {
6112 /* Some object formats don't support named sections at all. The
6113 front-end should already have flagged this as an error. */
6114 gcc_unreachable ();
6115 }
6116
6117 #ifndef TLS_SECTION_ASM_FLAG
6118 #define TLS_SECTION_ASM_FLAG 'T'
6119 #endif
6120
6121 void
6122 default_elf_asm_named_section (const char *name, unsigned int flags,
6123 tree decl ATTRIBUTE_UNUSED)
6124 {
6125 char flagchars[10], *f = flagchars;
6126
6127 /* If we have already declared this section, we can use an
6128 abbreviated form to switch back to it -- unless this section is
6129 part of a COMDAT groups, in which case GAS requires the full
6130 declaration every time. */
6131 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6132 && (flags & SECTION_DECLARED))
6133 {
6134 fprintf (asm_out_file, "\t.section\t%s\n", name);
6135 return;
6136 }
6137
6138 if (!(flags & SECTION_DEBUG))
6139 *f++ = 'a';
6140 if (flags & SECTION_EXCLUDE)
6141 *f++ = 'e';
6142 if (flags & SECTION_WRITE)
6143 *f++ = 'w';
6144 if (flags & SECTION_CODE)
6145 *f++ = 'x';
6146 if (flags & SECTION_SMALL)
6147 *f++ = 's';
6148 if (flags & SECTION_MERGE)
6149 *f++ = 'M';
6150 if (flags & SECTION_STRINGS)
6151 *f++ = 'S';
6152 if (flags & SECTION_TLS)
6153 *f++ = TLS_SECTION_ASM_FLAG;
6154 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6155 *f++ = 'G';
6156 *f = '\0';
6157
6158 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6159
6160 if (!(flags & SECTION_NOTYPE))
6161 {
6162 const char *type;
6163 const char *format;
6164
6165 if (flags & SECTION_BSS)
6166 type = "nobits";
6167 else
6168 type = "progbits";
6169
6170 format = ",@%s";
6171 /* On platforms that use "@" as the assembly comment character,
6172 use "%" instead. */
6173 if (strcmp (ASM_COMMENT_START, "@") == 0)
6174 format = ",%%%s";
6175 fprintf (asm_out_file, format, type);
6176
6177 if (flags & SECTION_ENTSIZE)
6178 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6179 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6180 {
6181 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6182 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6183 else
6184 fprintf (asm_out_file, ",%s,comdat",
6185 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6186 }
6187 }
6188
6189 putc ('\n', asm_out_file);
6190 }
6191
6192 void
6193 default_coff_asm_named_section (const char *name, unsigned int flags,
6194 tree decl ATTRIBUTE_UNUSED)
6195 {
6196 char flagchars[8], *f = flagchars;
6197
6198 if (flags & SECTION_WRITE)
6199 *f++ = 'w';
6200 if (flags & SECTION_CODE)
6201 *f++ = 'x';
6202 *f = '\0';
6203
6204 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6205 }
6206
6207 void
6208 default_pe_asm_named_section (const char *name, unsigned int flags,
6209 tree decl)
6210 {
6211 default_coff_asm_named_section (name, flags, decl);
6212
6213 if (flags & SECTION_LINKONCE)
6214 {
6215 /* Functions may have been compiled at various levels of
6216 optimization so we can't use `same_size' here.
6217 Instead, have the linker pick one. */
6218 fprintf (asm_out_file, "\t.linkonce %s\n",
6219 (flags & SECTION_CODE ? "discard" : "same_size"));
6220 }
6221 }
6222 \f
6223 /* The lame default section selector. */
6224
6225 section *
6226 default_select_section (tree decl, int reloc,
6227 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6228 {
6229 if (DECL_P (decl))
6230 {
6231 if (decl_readonly_section (decl, reloc))
6232 return readonly_data_section;
6233 }
6234 else if (TREE_CODE (decl) == CONSTRUCTOR)
6235 {
6236 if (! ((flag_pic && reloc)
6237 || !TREE_READONLY (decl)
6238 || TREE_SIDE_EFFECTS (decl)
6239 || !TREE_CONSTANT (decl)))
6240 return readonly_data_section;
6241 }
6242 else if (TREE_CODE (decl) == STRING_CST)
6243 return readonly_data_section;
6244 else if (! (flag_pic && reloc))
6245 return readonly_data_section;
6246
6247 return data_section;
6248 }
6249
6250 enum section_category
6251 categorize_decl_for_section (const_tree decl, int reloc)
6252 {
6253 enum section_category ret;
6254
6255 if (TREE_CODE (decl) == FUNCTION_DECL)
6256 return SECCAT_TEXT;
6257 else if (TREE_CODE (decl) == STRING_CST)
6258 {
6259 if ((flag_sanitize & SANITIZE_ADDRESS)
6260 && asan_protect_global (CONST_CAST_TREE (decl)))
6261 /* or !flag_merge_constants */
6262 return SECCAT_RODATA;
6263 else
6264 return SECCAT_RODATA_MERGE_STR;
6265 }
6266 else if (TREE_CODE (decl) == VAR_DECL)
6267 {
6268 if (bss_initializer_p (decl))
6269 ret = SECCAT_BSS;
6270 else if (! TREE_READONLY (decl)
6271 || TREE_SIDE_EFFECTS (decl)
6272 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
6273 {
6274 /* Here the reloc_rw_mask is not testing whether the section should
6275 be read-only or not, but whether the dynamic link will have to
6276 do something. If so, we wish to segregate the data in order to
6277 minimize cache misses inside the dynamic linker. */
6278 if (reloc & targetm.asm_out.reloc_rw_mask ())
6279 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6280 else
6281 ret = SECCAT_DATA;
6282 }
6283 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6284 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6285 else if (reloc || flag_merge_constants < 2
6286 || ((flag_sanitize & SANITIZE_ADDRESS)
6287 && asan_protect_global (CONST_CAST_TREE (decl))))
6288 /* C and C++ don't allow different variables to share the same
6289 location. -fmerge-all-constants allows even that (at the
6290 expense of not conforming). */
6291 ret = SECCAT_RODATA;
6292 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6293 ret = SECCAT_RODATA_MERGE_STR_INIT;
6294 else
6295 ret = SECCAT_RODATA_MERGE_CONST;
6296 }
6297 else if (TREE_CODE (decl) == CONSTRUCTOR)
6298 {
6299 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6300 || TREE_SIDE_EFFECTS (decl)
6301 || ! TREE_CONSTANT (decl))
6302 ret = SECCAT_DATA;
6303 else
6304 ret = SECCAT_RODATA;
6305 }
6306 else
6307 ret = SECCAT_RODATA;
6308
6309 /* There are no read-only thread-local sections. */
6310 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6311 {
6312 /* Note that this would be *just* SECCAT_BSS, except that there's
6313 no concept of a read-only thread-local-data section. */
6314 if (ret == SECCAT_BSS
6315 || (flag_zero_initialized_in_bss
6316 && initializer_zerop (DECL_INITIAL (decl))))
6317 ret = SECCAT_TBSS;
6318 else
6319 ret = SECCAT_TDATA;
6320 }
6321
6322 /* If the target uses small data sections, select it. */
6323 else if (targetm.in_small_data_p (decl))
6324 {
6325 if (ret == SECCAT_BSS)
6326 ret = SECCAT_SBSS;
6327 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6328 ret = SECCAT_SRODATA;
6329 else
6330 ret = SECCAT_SDATA;
6331 }
6332
6333 return ret;
6334 }
6335
6336 static bool
6337 decl_readonly_section_1 (enum section_category category)
6338 {
6339 switch (category)
6340 {
6341 case SECCAT_RODATA:
6342 case SECCAT_RODATA_MERGE_STR:
6343 case SECCAT_RODATA_MERGE_STR_INIT:
6344 case SECCAT_RODATA_MERGE_CONST:
6345 case SECCAT_SRODATA:
6346 return true;
6347 default:
6348 return false;
6349 }
6350 }
6351
6352 bool
6353 decl_readonly_section (const_tree decl, int reloc)
6354 {
6355 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6356 }
6357
6358 /* Select a section based on the above categorization. */
6359
6360 section *
6361 default_elf_select_section (tree decl, int reloc,
6362 unsigned HOST_WIDE_INT align)
6363 {
6364 const char *sname;
6365 switch (categorize_decl_for_section (decl, reloc))
6366 {
6367 case SECCAT_TEXT:
6368 /* We're not supposed to be called on FUNCTION_DECLs. */
6369 gcc_unreachable ();
6370 case SECCAT_RODATA:
6371 return readonly_data_section;
6372 case SECCAT_RODATA_MERGE_STR:
6373 return mergeable_string_section (decl, align, 0);
6374 case SECCAT_RODATA_MERGE_STR_INIT:
6375 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6376 case SECCAT_RODATA_MERGE_CONST:
6377 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6378 case SECCAT_SRODATA:
6379 sname = ".sdata2";
6380 break;
6381 case SECCAT_DATA:
6382 return data_section;
6383 case SECCAT_DATA_REL:
6384 sname = ".data.rel";
6385 break;
6386 case SECCAT_DATA_REL_LOCAL:
6387 sname = ".data.rel.local";
6388 break;
6389 case SECCAT_DATA_REL_RO:
6390 sname = ".data.rel.ro";
6391 break;
6392 case SECCAT_DATA_REL_RO_LOCAL:
6393 sname = ".data.rel.ro.local";
6394 break;
6395 case SECCAT_SDATA:
6396 sname = ".sdata";
6397 break;
6398 case SECCAT_TDATA:
6399 sname = ".tdata";
6400 break;
6401 case SECCAT_BSS:
6402 if (bss_section)
6403 return bss_section;
6404 sname = ".bss";
6405 break;
6406 case SECCAT_SBSS:
6407 sname = ".sbss";
6408 break;
6409 case SECCAT_TBSS:
6410 sname = ".tbss";
6411 break;
6412 default:
6413 gcc_unreachable ();
6414 }
6415
6416 return get_named_section (decl, sname, reloc);
6417 }
6418
6419 /* Construct a unique section name based on the decl name and the
6420 categorization performed above. */
6421
6422 void
6423 default_unique_section (tree decl, int reloc)
6424 {
6425 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6426 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6427 const char *prefix, *name, *linkonce;
6428 char *string;
6429
6430 switch (categorize_decl_for_section (decl, reloc))
6431 {
6432 case SECCAT_TEXT:
6433 prefix = one_only ? ".t" : ".text";
6434 break;
6435 case SECCAT_RODATA:
6436 case SECCAT_RODATA_MERGE_STR:
6437 case SECCAT_RODATA_MERGE_STR_INIT:
6438 case SECCAT_RODATA_MERGE_CONST:
6439 prefix = one_only ? ".r" : ".rodata";
6440 break;
6441 case SECCAT_SRODATA:
6442 prefix = one_only ? ".s2" : ".sdata2";
6443 break;
6444 case SECCAT_DATA:
6445 prefix = one_only ? ".d" : ".data";
6446 break;
6447 case SECCAT_DATA_REL:
6448 prefix = one_only ? ".d.rel" : ".data.rel";
6449 break;
6450 case SECCAT_DATA_REL_LOCAL:
6451 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6452 break;
6453 case SECCAT_DATA_REL_RO:
6454 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6455 break;
6456 case SECCAT_DATA_REL_RO_LOCAL:
6457 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6458 break;
6459 case SECCAT_SDATA:
6460 prefix = one_only ? ".s" : ".sdata";
6461 break;
6462 case SECCAT_BSS:
6463 prefix = one_only ? ".b" : ".bss";
6464 break;
6465 case SECCAT_SBSS:
6466 prefix = one_only ? ".sb" : ".sbss";
6467 break;
6468 case SECCAT_TDATA:
6469 prefix = one_only ? ".td" : ".tdata";
6470 break;
6471 case SECCAT_TBSS:
6472 prefix = one_only ? ".tb" : ".tbss";
6473 break;
6474 default:
6475 gcc_unreachable ();
6476 }
6477
6478 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
6479 name = targetm.strip_name_encoding (name);
6480
6481 /* If we're using one_only, then there needs to be a .gnu.linkonce
6482 prefix to the section name. */
6483 linkonce = one_only ? ".gnu.linkonce" : "";
6484
6485 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6486
6487 set_decl_section_name (decl, string);
6488 }
6489
6490 /* Subroutine of compute_reloc_for_rtx for leaf rtxes. */
6491
6492 static int
6493 compute_reloc_for_rtx_1 (const_rtx x)
6494 {
6495 switch (GET_CODE (x))
6496 {
6497 case SYMBOL_REF:
6498 return SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6499 case LABEL_REF:
6500 return 1;
6501 default:
6502 return 0;
6503 }
6504 }
6505
6506 /* Like compute_reloc_for_constant, except for an RTX. The return value
6507 is a mask for which bit 1 indicates a global relocation, and bit 0
6508 indicates a local relocation. */
6509
6510 static int
6511 compute_reloc_for_rtx (const_rtx x)
6512 {
6513 switch (GET_CODE (x))
6514 {
6515 case SYMBOL_REF:
6516 case LABEL_REF:
6517 return compute_reloc_for_rtx_1 (x);
6518
6519 case CONST:
6520 {
6521 int reloc = 0;
6522 subrtx_iterator::array_type array;
6523 FOR_EACH_SUBRTX (iter, array, x, ALL)
6524 reloc |= compute_reloc_for_rtx_1 (*iter);
6525 return reloc;
6526 }
6527
6528 default:
6529 return 0;
6530 }
6531 }
6532
6533 section *
6534 default_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
6535 rtx x,
6536 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6537 {
6538 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6539 return data_section;
6540 else
6541 return readonly_data_section;
6542 }
6543
6544 section *
6545 default_elf_select_rtx_section (enum machine_mode mode, rtx x,
6546 unsigned HOST_WIDE_INT align)
6547 {
6548 int reloc = compute_reloc_for_rtx (x);
6549
6550 /* ??? Handle small data here somehow. */
6551
6552 if (reloc & targetm.asm_out.reloc_rw_mask ())
6553 {
6554 if (reloc == 1)
6555 return get_named_section (NULL, ".data.rel.ro.local", 1);
6556 else
6557 return get_named_section (NULL, ".data.rel.ro", 3);
6558 }
6559
6560 return mergeable_constant_section (mode, align, 0);
6561 }
6562
6563 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6564
6565 void
6566 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6567 {
6568 rtx symbol;
6569 int flags;
6570
6571 /* Careful not to prod global register variables. */
6572 if (!MEM_P (rtl))
6573 return;
6574 symbol = XEXP (rtl, 0);
6575 if (GET_CODE (symbol) != SYMBOL_REF)
6576 return;
6577
6578 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6579 if (TREE_CODE (decl) == FUNCTION_DECL)
6580 flags |= SYMBOL_FLAG_FUNCTION;
6581 if (targetm.binds_local_p (decl))
6582 flags |= SYMBOL_FLAG_LOCAL;
6583 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6584 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6585 else if (targetm.in_small_data_p (decl))
6586 flags |= SYMBOL_FLAG_SMALL;
6587 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6588 being PUBLIC, the thing *must* be defined in this translation unit.
6589 Prevent this buglet from being propagated into rtl code as well. */
6590 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6591 flags |= SYMBOL_FLAG_EXTERNAL;
6592
6593 SYMBOL_REF_FLAGS (symbol) = flags;
6594 }
6595
6596 /* By default, we do nothing for encode_section_info, so we need not
6597 do anything but discard the '*' marker. */
6598
6599 const char *
6600 default_strip_name_encoding (const char *str)
6601 {
6602 return str + (*str == '*');
6603 }
6604
6605 #ifdef ASM_OUTPUT_DEF
6606 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6607 anchor relative to ".", the current section position. */
6608
6609 void
6610 default_asm_output_anchor (rtx symbol)
6611 {
6612 char buffer[100];
6613
6614 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6615 SYMBOL_REF_BLOCK_OFFSET (symbol));
6616 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6617 }
6618 #endif
6619
6620 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6621
6622 bool
6623 default_use_anchors_for_symbol_p (const_rtx symbol)
6624 {
6625 section *sect;
6626 tree decl;
6627
6628 /* Don't use anchors for mergeable sections. The linker might move
6629 the objects around. */
6630 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6631 if (sect->common.flags & SECTION_MERGE)
6632 return false;
6633
6634 /* Don't use anchors for small data sections. The small data register
6635 acts as an anchor for such sections. */
6636 if (sect->common.flags & SECTION_SMALL)
6637 return false;
6638
6639 decl = SYMBOL_REF_DECL (symbol);
6640 if (decl && DECL_P (decl))
6641 {
6642 /* Don't use section anchors for decls that might be defined or
6643 usurped by other modules. */
6644 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6645 return false;
6646
6647 /* Don't use section anchors for decls that will be placed in a
6648 small data section. */
6649 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6650 one above. The problem is that we only use SECTION_SMALL for
6651 sections that should be marked as small in the section directive. */
6652 if (targetm.in_small_data_p (decl))
6653 return false;
6654 }
6655 return true;
6656 }
6657
6658 /* Return true when RESOLUTION indicate that symbol will be bound to the
6659 definition provided by current .o file. */
6660
6661 static bool
6662 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
6663 {
6664 return (resolution == LDPR_PREVAILING_DEF
6665 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6666 || resolution == LDPR_PREVAILING_DEF_IRONLY);
6667 }
6668
6669 /* Return true when RESOLUTION indicate that symbol will be bound locally
6670 within current executable or DSO. */
6671
6672 static bool
6673 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
6674 {
6675 return (resolution == LDPR_PREVAILING_DEF
6676 || resolution == LDPR_PREVAILING_DEF_IRONLY
6677 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6678 || resolution == LDPR_PREEMPTED_REG
6679 || resolution == LDPR_PREEMPTED_IR
6680 || resolution == LDPR_RESOLVED_IR
6681 || resolution == LDPR_RESOLVED_EXEC);
6682 }
6683
6684 /* Assume ELF-ish defaults, since that's pretty much the most liberal
6685 wrt cross-module name binding. */
6686
6687 bool
6688 default_binds_local_p (const_tree exp)
6689 {
6690 return default_binds_local_p_1 (exp, flag_shlib);
6691 }
6692
6693 bool
6694 default_binds_local_p_1 (const_tree exp, int shlib)
6695 {
6696 bool local_p;
6697 bool resolved_locally = false;
6698 bool resolved_to_local_def = false;
6699
6700 /* With resolution file in hands, take look into resolutions.
6701 We can't just return true for resolved_locally symbols,
6702 because dynamic linking might overwrite symbols
6703 in shared libraries. */
6704 if (TREE_CODE (exp) == VAR_DECL && TREE_PUBLIC (exp)
6705 && (TREE_STATIC (exp) || DECL_EXTERNAL (exp)))
6706 {
6707 varpool_node *vnode = varpool_node::get (exp);
6708 if (vnode && (resolution_local_p (vnode->resolution) || vnode->in_other_partition))
6709 resolved_locally = true;
6710 if (vnode
6711 && resolution_to_local_definition_p (vnode->resolution))
6712 resolved_to_local_def = true;
6713 }
6714 else if (TREE_CODE (exp) == FUNCTION_DECL && TREE_PUBLIC (exp))
6715 {
6716 struct cgraph_node *node = cgraph_node::get (exp);
6717 if (node
6718 && (resolution_local_p (node->resolution) || node->in_other_partition))
6719 resolved_locally = true;
6720 if (node
6721 && resolution_to_local_definition_p (node->resolution))
6722 resolved_to_local_def = true;
6723 }
6724
6725 /* A non-decl is an entry in the constant pool. */
6726 if (!DECL_P (exp))
6727 local_p = true;
6728 /* Weakrefs may not bind locally, even though the weakref itself is always
6729 static and therefore local. Similarly, the resolver for ifunc functions
6730 might resolve to a non-local function.
6731 FIXME: We can resolve the weakref case more curefuly by looking at the
6732 weakref alias. */
6733 else if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
6734 || (TREE_CODE (exp) == FUNCTION_DECL
6735 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
6736 local_p = false;
6737 /* Static variables are always local. */
6738 else if (! TREE_PUBLIC (exp))
6739 local_p = true;
6740 /* A variable is local if the user has said explicitly that it will
6741 be. */
6742 else if ((DECL_VISIBILITY_SPECIFIED (exp)
6743 || resolved_to_local_def)
6744 && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6745 local_p = true;
6746 /* Variables defined outside this object might not be local. */
6747 else if (DECL_EXTERNAL (exp) && !resolved_locally)
6748 local_p = false;
6749 /* If defined in this object and visibility is not default, must be
6750 local. */
6751 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6752 local_p = true;
6753 /* Default visibility weak data can be overridden by a strong symbol
6754 in another module and so are not local. */
6755 else if (DECL_WEAK (exp)
6756 && !resolved_locally)
6757 local_p = false;
6758 /* If PIC, then assume that any global name can be overridden by
6759 symbols resolved from other modules. */
6760 else if (shlib)
6761 local_p = false;
6762 /* Uninitialized COMMON variable may be unified with symbols
6763 resolved from other modules. */
6764 else if (DECL_COMMON (exp)
6765 && !resolved_locally
6766 && (DECL_INITIAL (exp) == NULL
6767 || (!in_lto_p && DECL_INITIAL (exp) == error_mark_node)))
6768 local_p = false;
6769 /* Otherwise we're left with initialized (or non-common) global data
6770 which is of necessity defined locally. */
6771 else
6772 local_p = true;
6773
6774 return local_p;
6775 }
6776
6777 /* Return true when references to DECL must bind to current definition in
6778 final executable.
6779
6780 The condition is usually equivalent to whether the function binds to the
6781 current module (shared library or executable), that is to binds_local_p.
6782 We use this fact to avoid need for another target hook and implement
6783 the logic using binds_local_p and just special cases where
6784 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
6785 the weak definitions (that can be overwritten at linktime by other
6786 definition from different object file) and when resolution info is available
6787 we simply use the knowledge passed to us by linker plugin. */
6788 bool
6789 decl_binds_to_current_def_p (const_tree decl)
6790 {
6791 gcc_assert (DECL_P (decl));
6792 if (!targetm.binds_local_p (decl))
6793 return false;
6794 if (!TREE_PUBLIC (decl))
6795 return true;
6796 /* When resolution is available, just use it. */
6797 if (TREE_CODE (decl) == VAR_DECL
6798 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl)))
6799 {
6800 varpool_node *vnode = varpool_node::get (decl);
6801 if (vnode
6802 && vnode->resolution != LDPR_UNKNOWN)
6803 return resolution_to_local_definition_p (vnode->resolution);
6804 }
6805 else if (TREE_CODE (decl) == FUNCTION_DECL)
6806 {
6807 struct cgraph_node *node = cgraph_node::get (decl);
6808 if (node
6809 && node->resolution != LDPR_UNKNOWN)
6810 return resolution_to_local_definition_p (node->resolution);
6811 }
6812 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
6813 binds locally but still can be overwritten), DECL_COMMON (can be merged
6814 with a non-common definition somewhere in the same module) or
6815 DECL_EXTERNAL.
6816 This rely on fact that binds_local_p behave as decl_replaceable_p
6817 for all other declaration types. */
6818 if (DECL_WEAK (decl))
6819 return false;
6820 if (DECL_COMMON (decl)
6821 && (DECL_INITIAL (decl) == NULL
6822 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
6823 return false;
6824 if (DECL_EXTERNAL (decl))
6825 return false;
6826 return true;
6827 }
6828
6829 /* A replaceable function or variable is one which may be replaced
6830 at link-time with an entirely different definition, provided that the
6831 replacement has the same type. For example, functions declared
6832 with __attribute__((weak)) on most systems are replaceable.
6833
6834 COMDAT functions are not replaceable, since all definitions of the
6835 function must be equivalent. It is important that COMDAT functions
6836 not be treated as replaceable so that use of C++ template
6837 instantiations is not penalized. */
6838
6839 bool
6840 decl_replaceable_p (tree decl)
6841 {
6842 gcc_assert (DECL_P (decl));
6843 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
6844 return false;
6845 if (!flag_semantic_interposition
6846 && !DECL_WEAK (decl))
6847 return false;
6848 return !decl_binds_to_current_def_p (decl);
6849 }
6850
6851 /* Default function to output code that will globalize a label. A
6852 target must define GLOBAL_ASM_OP or provide its own function to
6853 globalize a label. */
6854 #ifdef GLOBAL_ASM_OP
6855 void
6856 default_globalize_label (FILE * stream, const char *name)
6857 {
6858 fputs (GLOBAL_ASM_OP, stream);
6859 assemble_name (stream, name);
6860 putc ('\n', stream);
6861 }
6862 #endif /* GLOBAL_ASM_OP */
6863
6864 /* Default function to output code that will globalize a declaration. */
6865 void
6866 default_globalize_decl_name (FILE * stream, tree decl)
6867 {
6868 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
6869 targetm.asm_out.globalize_label (stream, name);
6870 }
6871
6872 /* Default function to output a label for unwind information. The
6873 default is to do nothing. A target that needs nonlocal labels for
6874 unwind information must provide its own function to do this. */
6875 void
6876 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
6877 tree decl ATTRIBUTE_UNUSED,
6878 int for_eh ATTRIBUTE_UNUSED,
6879 int empty ATTRIBUTE_UNUSED)
6880 {
6881 }
6882
6883 /* Default function to output a label to divide up the exception table.
6884 The default is to do nothing. A target that needs/wants to divide
6885 up the table must provide it's own function to do this. */
6886 void
6887 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
6888 {
6889 }
6890
6891 /* This is how to output an internal numbered label where PREFIX is
6892 the class of label and LABELNO is the number within the class. */
6893
6894 void
6895 default_generate_internal_label (char *buf, const char *prefix,
6896 unsigned long labelno)
6897 {
6898 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6899 }
6900
6901 /* This is how to output an internal numbered label where PREFIX is
6902 the class of label and LABELNO is the number within the class. */
6903
6904 void
6905 default_internal_label (FILE *stream, const char *prefix,
6906 unsigned long labelno)
6907 {
6908 char *const buf = (char *) alloca (40 + strlen (prefix));
6909 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6910 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
6911 }
6912
6913
6914 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
6915
6916 void
6917 default_asm_declare_constant_name (FILE *file, const char *name,
6918 const_tree exp ATTRIBUTE_UNUSED,
6919 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
6920 {
6921 assemble_label (file, name);
6922 }
6923
6924 /* This is the default behavior at the beginning of a file. It's
6925 controlled by two other target-hook toggles. */
6926 void
6927 default_file_start (void)
6928 {
6929 if (targetm.asm_file_start_app_off
6930 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
6931 fputs (ASM_APP_OFF, asm_out_file);
6932
6933 if (targetm.asm_file_start_file_directive)
6934 output_file_directive (asm_out_file, main_input_filename);
6935 }
6936
6937 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
6938 which emits a special section directive used to indicate whether or
6939 not this object file needs an executable stack. This is primarily
6940 a GNU extension to ELF but could be used on other targets. */
6941
6942 int trampolines_created;
6943
6944 void
6945 file_end_indicate_exec_stack (void)
6946 {
6947 unsigned int flags = SECTION_DEBUG;
6948 if (trampolines_created)
6949 flags |= SECTION_CODE;
6950
6951 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
6952 }
6953
6954 /* Emit a special section directive to indicate that this object file
6955 was compiled with -fsplit-stack. This is used to let the linker
6956 detect calls between split-stack code and non-split-stack code, so
6957 that it can modify the split-stack code to allocate a sufficiently
6958 large stack. We emit another special section if there are any
6959 functions in this file which have the no_split_stack attribute, to
6960 prevent the linker from warning about being unable to convert the
6961 functions if they call non-split-stack code. */
6962
6963 void
6964 file_end_indicate_split_stack (void)
6965 {
6966 if (flag_split_stack)
6967 {
6968 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
6969 NULL));
6970 if (saw_no_split_stack)
6971 switch_to_section (get_section (".note.GNU-no-split-stack",
6972 SECTION_DEBUG, NULL));
6973 }
6974 }
6975
6976 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
6977 a get_unnamed_section callback. */
6978
6979 void
6980 output_section_asm_op (const void *directive)
6981 {
6982 fprintf (asm_out_file, "%s\n", (const char *) directive);
6983 }
6984
6985 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
6986 the current section is NEW_SECTION. */
6987
6988 void
6989 switch_to_section (section *new_section)
6990 {
6991 if (in_section == new_section)
6992 return;
6993
6994 if (new_section->common.flags & SECTION_FORGET)
6995 in_section = NULL;
6996 else
6997 in_section = new_section;
6998
6999 switch (SECTION_STYLE (new_section))
7000 {
7001 case SECTION_NAMED:
7002 targetm.asm_out.named_section (new_section->named.name,
7003 new_section->named.common.flags,
7004 new_section->named.decl);
7005 break;
7006
7007 case SECTION_UNNAMED:
7008 new_section->unnamed.callback (new_section->unnamed.data);
7009 break;
7010
7011 case SECTION_NOSWITCH:
7012 gcc_unreachable ();
7013 break;
7014 }
7015
7016 new_section->common.flags |= SECTION_DECLARED;
7017 }
7018
7019 /* If block symbol SYMBOL has not yet been assigned an offset, place
7020 it at the end of its block. */
7021
7022 void
7023 place_block_symbol (rtx symbol)
7024 {
7025 unsigned HOST_WIDE_INT size, mask, offset;
7026 struct constant_descriptor_rtx *desc;
7027 unsigned int alignment;
7028 struct object_block *block;
7029 tree decl;
7030
7031 gcc_assert (SYMBOL_REF_BLOCK (symbol));
7032 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7033 return;
7034
7035 /* Work out the symbol's size and alignment. */
7036 if (CONSTANT_POOL_ADDRESS_P (symbol))
7037 {
7038 desc = SYMBOL_REF_CONSTANT (symbol);
7039 alignment = desc->align;
7040 size = GET_MODE_SIZE (desc->mode);
7041 }
7042 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7043 {
7044 decl = SYMBOL_REF_DECL (symbol);
7045 alignment = DECL_ALIGN (decl);
7046 size = get_constant_size (DECL_INITIAL (decl));
7047 if ((flag_sanitize & SANITIZE_ADDRESS)
7048 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7049 && asan_protect_global (DECL_INITIAL (decl)))
7050 size += asan_red_zone_size (size);
7051 }
7052 else
7053 {
7054 struct symtab_node *snode;
7055 decl = SYMBOL_REF_DECL (symbol);
7056
7057 snode = symtab_node::get (decl);
7058 if (snode->alias)
7059 {
7060 rtx target = DECL_RTL (snode->ultimate_alias_target ()->decl);
7061
7062 place_block_symbol (target);
7063 SYMBOL_REF_BLOCK_OFFSET (symbol) = SYMBOL_REF_BLOCK_OFFSET (target);
7064 return;
7065 }
7066 alignment = get_variable_align (decl);
7067 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7068 if ((flag_sanitize & SANITIZE_ADDRESS)
7069 && asan_protect_global (decl))
7070 {
7071 size += asan_red_zone_size (size);
7072 alignment = MAX (alignment,
7073 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7074 }
7075 }
7076
7077 /* Calculate the object's offset from the start of the block. */
7078 block = SYMBOL_REF_BLOCK (symbol);
7079 mask = alignment / BITS_PER_UNIT - 1;
7080 offset = (block->size + mask) & ~mask;
7081 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7082
7083 /* Record the block's new alignment and size. */
7084 block->alignment = MAX (block->alignment, alignment);
7085 block->size = offset + size;
7086
7087 vec_safe_push (block->objects, symbol);
7088 }
7089
7090 /* Return the anchor that should be used to address byte offset OFFSET
7091 from the first object in BLOCK. MODEL is the TLS model used
7092 to access it. */
7093
7094 rtx
7095 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7096 enum tls_model model)
7097 {
7098 char label[100];
7099 unsigned int begin, middle, end;
7100 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7101 rtx anchor;
7102
7103 /* Work out the anchor's offset. Use an offset of 0 for the first
7104 anchor so that we don't pessimize the case where we take the address
7105 of a variable at the beginning of the block. This is particularly
7106 useful when a block has only one variable assigned to it.
7107
7108 We try to place anchors RANGE bytes apart, so there can then be
7109 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7110 a ptr_mode offset. With some target settings, the lowest such
7111 anchor might be out of range for the lowest ptr_mode offset;
7112 likewise the highest anchor for the highest offset. Use anchors
7113 at the extreme ends of the ptr_mode range in such cases.
7114
7115 All arithmetic uses unsigned integers in order to avoid
7116 signed overflow. */
7117 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7118 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7119 range = max_offset - min_offset + 1;
7120 if (range == 0)
7121 offset = 0;
7122 else
7123 {
7124 bias = 1 << (GET_MODE_BITSIZE (ptr_mode) - 1);
7125 if (offset < 0)
7126 {
7127 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7128 delta -= delta % range;
7129 if (delta > bias)
7130 delta = bias;
7131 offset = (HOST_WIDE_INT) (-delta);
7132 }
7133 else
7134 {
7135 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7136 delta -= delta % range;
7137 if (delta > bias - 1)
7138 delta = bias - 1;
7139 offset = (HOST_WIDE_INT) delta;
7140 }
7141 }
7142
7143 /* Do a binary search to see if there's already an anchor we can use.
7144 Set BEGIN to the new anchor's index if not. */
7145 begin = 0;
7146 end = vec_safe_length (block->anchors);
7147 while (begin != end)
7148 {
7149 middle = (end + begin) / 2;
7150 anchor = (*block->anchors)[middle];
7151 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7152 end = middle;
7153 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7154 begin = middle + 1;
7155 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7156 end = middle;
7157 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7158 begin = middle + 1;
7159 else
7160 return anchor;
7161 }
7162
7163 /* Create a new anchor with a unique label. */
7164 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7165 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7166 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7167 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7168
7169 /* Insert it at index BEGIN. */
7170 vec_safe_insert (block->anchors, begin, anchor);
7171 return anchor;
7172 }
7173
7174 /* Output the objects in BLOCK. */
7175
7176 static void
7177 output_object_block (struct object_block *block)
7178 {
7179 struct constant_descriptor_rtx *desc;
7180 unsigned int i;
7181 HOST_WIDE_INT offset;
7182 tree decl;
7183 rtx symbol;
7184
7185 if (!block->objects)
7186 return;
7187
7188 /* Switch to the section and make sure that the first byte is
7189 suitably aligned. */
7190 switch_to_section (block->sect);
7191 assemble_align (block->alignment);
7192
7193 /* Define the values of all anchors relative to the current section
7194 position. */
7195 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7196 targetm.asm_out.output_anchor (symbol);
7197
7198 /* Output the objects themselves. */
7199 offset = 0;
7200 FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7201 {
7202 /* Move to the object's offset, padding with zeros if necessary. */
7203 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7204 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7205 if (CONSTANT_POOL_ADDRESS_P (symbol))
7206 {
7207 desc = SYMBOL_REF_CONSTANT (symbol);
7208 output_constant_pool_1 (desc, 1);
7209 offset += GET_MODE_SIZE (desc->mode);
7210 }
7211 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7212 {
7213 HOST_WIDE_INT size;
7214 decl = SYMBOL_REF_DECL (symbol);
7215 assemble_constant_contents (DECL_INITIAL (decl), XSTR (symbol, 0),
7216 DECL_ALIGN (decl));
7217 size = get_constant_size (DECL_INITIAL (decl));
7218 offset += size;
7219 if ((flag_sanitize & SANITIZE_ADDRESS)
7220 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7221 && asan_protect_global (DECL_INITIAL (decl)))
7222 {
7223 size = asan_red_zone_size (size);
7224 assemble_zeros (size);
7225 offset += size;
7226 }
7227 }
7228 else
7229 {
7230 HOST_WIDE_INT size;
7231 decl = SYMBOL_REF_DECL (symbol);
7232 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7233 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7234 offset += size;
7235 if ((flag_sanitize & SANITIZE_ADDRESS)
7236 && asan_protect_global (decl))
7237 {
7238 size = asan_red_zone_size (size);
7239 assemble_zeros (size);
7240 offset += size;
7241 }
7242 }
7243 }
7244 }
7245
7246 /* A htab_traverse callback used to call output_object_block for
7247 each member of object_block_htab. */
7248
7249 static int
7250 output_object_block_htab (void **slot, void *data ATTRIBUTE_UNUSED)
7251 {
7252 output_object_block ((struct object_block *) (*slot));
7253 return 1;
7254 }
7255
7256 /* Output the definitions of all object_blocks. */
7257
7258 void
7259 output_object_blocks (void)
7260 {
7261 htab_traverse (object_block_htab, output_object_block_htab, NULL);
7262 }
7263
7264 /* This function provides a possible implementation of the
7265 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7266 by -frecord-gcc-switches it creates a new mergeable, string section in the
7267 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7268 contains the switches in ASCII format.
7269
7270 FIXME: This code does not correctly handle double quote characters
7271 that appear inside strings, (it strips them rather than preserving them).
7272 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7273 characters - instead it treats them as sub-string separators. Since
7274 we want to emit NUL strings terminators into the object file we have to use
7275 ASM_OUTPUT_SKIP. */
7276
7277 int
7278 elf_record_gcc_switches (print_switch_type type, const char * name)
7279 {
7280 switch (type)
7281 {
7282 case SWITCH_TYPE_PASSED:
7283 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7284 ASM_OUTPUT_SKIP (asm_out_file, (unsigned HOST_WIDE_INT) 1);
7285 break;
7286
7287 case SWITCH_TYPE_DESCRIPTIVE:
7288 if (name == NULL)
7289 {
7290 /* Distinguish between invocations where name is NULL. */
7291 static bool started = false;
7292
7293 if (!started)
7294 {
7295 section * sec;
7296
7297 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7298 SECTION_DEBUG
7299 | SECTION_MERGE
7300 | SECTION_STRINGS
7301 | (SECTION_ENTSIZE & 1),
7302 NULL);
7303 switch_to_section (sec);
7304 started = true;
7305 }
7306 }
7307
7308 default:
7309 break;
7310 }
7311
7312 /* The return value is currently ignored by the caller, but must be 0.
7313 For -fverbose-asm the return value would be the number of characters
7314 emitted into the assembler file. */
7315 return 0;
7316 }
7317
7318 /* Emit text to declare externally defined symbols. It is needed to
7319 properly support non-default visibility. */
7320 void
7321 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7322 tree decl,
7323 const char *name ATTRIBUTE_UNUSED)
7324 {
7325 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7326 set in order to avoid putting out names that are never really
7327 used. */
7328 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7329 && targetm.binds_local_p (decl))
7330 maybe_assemble_visibility (decl);
7331 }
7332
7333 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7334
7335 void
7336 default_asm_output_source_filename (FILE *file, const char *name)
7337 {
7338 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7339 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7340 #else
7341 fprintf (file, "\t.file\t");
7342 output_quoted_string (file, name);
7343 putc ('\n', file);
7344 #endif
7345 }
7346
7347 /* Output a file name in the form wanted by System V. */
7348
7349 void
7350 output_file_directive (FILE *asm_file, const char *input_name)
7351 {
7352 int len;
7353 const char *na;
7354
7355 if (input_name == NULL)
7356 input_name = "<stdin>";
7357 else
7358 input_name = remap_debug_filename (input_name);
7359
7360 len = strlen (input_name);
7361 na = input_name + len;
7362
7363 /* NA gets INPUT_NAME sans directory names. */
7364 while (na > input_name)
7365 {
7366 if (IS_DIR_SEPARATOR (na[-1]))
7367 break;
7368 na--;
7369 }
7370
7371 targetm.asm_out.output_source_filename (asm_file, na);
7372 }
7373
7374 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7375 EXP. */
7376 rtx
7377 make_debug_expr_from_rtl (const_rtx exp)
7378 {
7379 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7380 enum machine_mode mode = GET_MODE (exp);
7381 rtx dval;
7382
7383 DECL_ARTIFICIAL (ddecl) = 1;
7384 if (REG_P (exp) && REG_EXPR (exp))
7385 type = TREE_TYPE (REG_EXPR (exp));
7386 else if (MEM_P (exp) && MEM_EXPR (exp))
7387 type = TREE_TYPE (MEM_EXPR (exp));
7388 else
7389 type = NULL_TREE;
7390 if (type && TYPE_MODE (type) == mode)
7391 TREE_TYPE (ddecl) = type;
7392 else
7393 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7394 DECL_MODE (ddecl) = mode;
7395 dval = gen_rtx_DEBUG_EXPR (mode);
7396 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7397 SET_DECL_RTL (ddecl, dval);
7398 return dval;
7399 }
7400
7401 #ifdef ELF_ASCII_ESCAPES
7402 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7403
7404 void
7405 default_elf_asm_output_limited_string (FILE *f, const char *s)
7406 {
7407 int escape;
7408 unsigned char c;
7409
7410 fputs (STRING_ASM_OP, f);
7411 putc ('"', f);
7412 while (*s != '\0')
7413 {
7414 c = *s;
7415 escape = ELF_ASCII_ESCAPES[c];
7416 switch (escape)
7417 {
7418 case 0:
7419 putc (c, f);
7420 break;
7421 case 1:
7422 /* TODO: Print in hex with fast function, important for -flto. */
7423 fprintf (f, "\\%03o", c);
7424 break;
7425 default:
7426 putc ('\\', f);
7427 putc (escape, f);
7428 break;
7429 }
7430 s++;
7431 }
7432 putc ('\"', f);
7433 putc ('\n', f);
7434 }
7435
7436 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7437
7438 void
7439 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7440 {
7441 const char *limit = s + len;
7442 const char *last_null = NULL;
7443 unsigned bytes_in_chunk = 0;
7444 unsigned char c;
7445 int escape;
7446
7447 for (; s < limit; s++)
7448 {
7449 const char *p;
7450
7451 if (bytes_in_chunk >= 60)
7452 {
7453 putc ('\"', f);
7454 putc ('\n', f);
7455 bytes_in_chunk = 0;
7456 }
7457
7458 if (s > last_null)
7459 {
7460 for (p = s; p < limit && *p != '\0'; p++)
7461 continue;
7462 last_null = p;
7463 }
7464 else
7465 p = last_null;
7466
7467 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7468 {
7469 if (bytes_in_chunk > 0)
7470 {
7471 putc ('\"', f);
7472 putc ('\n', f);
7473 bytes_in_chunk = 0;
7474 }
7475
7476 default_elf_asm_output_limited_string (f, s);
7477 s = p;
7478 }
7479 else
7480 {
7481 if (bytes_in_chunk == 0)
7482 fputs (ASCII_DATA_ASM_OP "\"", f);
7483
7484 c = *s;
7485 escape = ELF_ASCII_ESCAPES[c];
7486 switch (escape)
7487 {
7488 case 0:
7489 putc (c, f);
7490 bytes_in_chunk++;
7491 break;
7492 case 1:
7493 /* TODO: Print in hex with fast function, important for -flto. */
7494 fprintf (f, "\\%03o", c);
7495 bytes_in_chunk += 4;
7496 break;
7497 default:
7498 putc ('\\', f);
7499 putc (escape, f);
7500 bytes_in_chunk += 2;
7501 break;
7502 }
7503
7504 }
7505 }
7506
7507 if (bytes_in_chunk > 0)
7508 {
7509 putc ('\"', f);
7510 putc ('\n', f);
7511 }
7512 }
7513 #endif
7514
7515 static GTY(()) section *elf_init_array_section;
7516 static GTY(()) section *elf_fini_array_section;
7517
7518 static section *
7519 get_elf_initfini_array_priority_section (int priority,
7520 bool constructor_p)
7521 {
7522 section *sec;
7523 if (priority != DEFAULT_INIT_PRIORITY)
7524 {
7525 char buf[18];
7526 sprintf (buf, "%s.%.5u",
7527 constructor_p ? ".init_array" : ".fini_array",
7528 priority);
7529 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7530 }
7531 else
7532 {
7533 if (constructor_p)
7534 {
7535 if (elf_init_array_section == NULL)
7536 elf_init_array_section
7537 = get_section (".init_array",
7538 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7539 sec = elf_init_array_section;
7540 }
7541 else
7542 {
7543 if (elf_fini_array_section == NULL)
7544 elf_fini_array_section
7545 = get_section (".fini_array",
7546 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7547 sec = elf_fini_array_section;
7548 }
7549 }
7550 return sec;
7551 }
7552
7553 /* Use .init_array section for constructors. */
7554
7555 void
7556 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7557 {
7558 section *sec = get_elf_initfini_array_priority_section (priority,
7559 true);
7560 assemble_addr_to_section (symbol, sec);
7561 }
7562
7563 /* Use .fini_array section for destructors. */
7564
7565 void
7566 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7567 {
7568 section *sec = get_elf_initfini_array_priority_section (priority,
7569 false);
7570 assemble_addr_to_section (symbol, sec);
7571 }
7572
7573 /* Default TARGET_ASM_OUTPUT_IDENT hook.
7574
7575 This is a bit of a cheat. The real default is a no-op, but this
7576 hook is the default for all targets with a .ident directive. */
7577
7578 void
7579 default_asm_output_ident_directive (const char *ident_str)
7580 {
7581 const char *ident_asm_op = "\t.ident\t";
7582
7583 /* If we are still in the front end, do not write out the string
7584 to asm_out_file. Instead, add a fake top-level asm statement.
7585 This allows the front ends to use this hook without actually
7586 writing to asm_out_file, to handle #ident or Pragma Ident. */
7587 if (symtab->state == PARSING)
7588 {
7589 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
7590 symtab->finalize_toplevel_asm (build_string (strlen (buf), buf));
7591 }
7592 else
7593 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
7594 }
7595
7596 #include "gt-varasm.h"