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