mode-classes.def (MODE_POINTER_BOUNDS): New.
[gcc.git] / gcc / varasm.c
1 /* Output variables, constants and external declarations, for GNU compiler.
2 Copyright (C) 1987-2013 Free Software Foundation, Inc.
3
4 This file is part of GCC.
5
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
10
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
15
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
19
20
21 /* This file handles generation of all the assembler code
22 *except* the instructions of a function.
23 This includes declarations of variables and their initial values.
24
25 We also output the assembler code for constants stored in memory
26 and are responsible for combining constants with the same value. */
27
28 #include "config.h"
29 #include "system.h"
30 #include "coretypes.h"
31 #include "tm.h"
32 #include "rtl.h"
33 #include "tree.h"
34 #include "flags.h"
35 #include "function.h"
36 #include "expr.h"
37 #include "hard-reg-set.h"
38 #include "regs.h"
39 #include "output.h"
40 #include "diagnostic-core.h"
41 #include "hashtab.h"
42 #include "ggc.h"
43 #include "langhooks.h"
44 #include "tm_p.h"
45 #include "debug.h"
46 #include "target.h"
47 #include "common/common-target.h"
48 #include "targhooks.h"
49 #include "tree-mudflap.h"
50 #include "cgraph.h"
51 #include "pointer-set.h"
52 #include "asan.h"
53 #include "basic-block.h"
54
55 #ifdef XCOFF_DEBUGGING_INFO
56 #include "xcoffout.h" /* Needed for external data
57 declarations for e.g. AIX 4.x. */
58 #endif
59
60 /* The (assembler) name of the first globally-visible object output. */
61 extern GTY(()) const char *first_global_object_name;
62 extern GTY(()) const char *weak_global_object_name;
63
64 const char *first_global_object_name;
65 const char *weak_global_object_name;
66
67 struct addr_const;
68 struct constant_descriptor_rtx;
69 struct rtx_constant_pool;
70
71 #define n_deferred_constants (crtl->varasm.deferred_constants)
72
73 /* Number for making the label on the next
74 constant that is stored in memory. */
75
76 static GTY(()) int const_labelno;
77
78 /* Carry information from ASM_DECLARE_OBJECT_NAME
79 to ASM_FINISH_DECLARE_OBJECT. */
80
81 int size_directive_output;
82
83 /* The last decl for which assemble_variable was called,
84 if it did ASM_DECLARE_OBJECT_NAME.
85 If the last call to assemble_variable didn't do that,
86 this holds 0. */
87
88 tree last_assemble_variable_decl;
89
90 /* The following global variable indicates if the first basic block
91 in a function belongs to the cold partition or not. */
92
93 bool first_function_block_is_cold;
94
95 /* We give all constants their own alias set. Perhaps redundant with
96 MEM_READONLY_P, but pre-dates it. */
97
98 static alias_set_type const_alias_set;
99
100 /* Whether we saw any functions with no_split_stack. */
101
102 static bool saw_no_split_stack;
103
104 static const char *strip_reg_name (const char *);
105 static int contains_pointers_p (tree);
106 #ifdef ASM_OUTPUT_EXTERNAL
107 static bool incorporeal_function_p (tree);
108 #endif
109 static void decode_addr_const (tree, struct addr_const *);
110 static hashval_t const_desc_hash (const void *);
111 static int const_desc_eq (const void *, const void *);
112 static hashval_t const_hash_1 (const tree);
113 static int compare_constant (const tree, const tree);
114 static tree copy_constant (tree);
115 static void output_constant_def_contents (rtx);
116 static void output_addressed_constants (tree);
117 static unsigned HOST_WIDE_INT array_size_for_constructor (tree);
118 static unsigned min_align (unsigned, unsigned);
119 static void globalize_decl (tree);
120 static bool decl_readonly_section_1 (enum section_category);
121 #ifdef BSS_SECTION_ASM_OP
122 #ifdef ASM_OUTPUT_ALIGNED_BSS
123 static void asm_output_aligned_bss (FILE *, tree, const char *,
124 unsigned HOST_WIDE_INT, int)
125 ATTRIBUTE_UNUSED;
126 #endif
127 #endif /* BSS_SECTION_ASM_OP */
128 static void mark_weak (tree);
129 static void output_constant_pool (const char *, tree);
130 \f
131 /* Well-known sections, each one associated with some sort of *_ASM_OP. */
132 section *text_section;
133 section *data_section;
134 section *readonly_data_section;
135 section *sdata_section;
136 section *ctors_section;
137 section *dtors_section;
138 section *bss_section;
139 section *sbss_section;
140
141 /* Various forms of common section. All are guaranteed to be nonnull. */
142 section *tls_comm_section;
143 section *comm_section;
144 section *lcomm_section;
145
146 /* A SECTION_NOSWITCH section used for declaring global BSS variables.
147 May be null. */
148 section *bss_noswitch_section;
149
150 /* The section that holds the main exception table, when known. The section
151 is set either by the target's init_sections hook or by the first call to
152 switch_to_exception_section. */
153 section *exception_section;
154
155 /* The section that holds the DWARF2 frame unwind information, when known.
156 The section is set either by the target's init_sections hook or by the
157 first call to switch_to_eh_frame_section. */
158 section *eh_frame_section;
159
160 /* asm_out_file's current section. This is NULL if no section has yet
161 been selected or if we lose track of what the current section is. */
162 section *in_section;
163
164 /* True if code for the current function is currently being directed
165 at the cold section. */
166 bool in_cold_section_p;
167
168 /* A linked list of all the unnamed sections. */
169 static GTY(()) section *unnamed_sections;
170
171 /* Return a nonzero value if DECL has a section attribute. */
172 #define IN_NAMED_SECTION(DECL) \
173 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \
174 && DECL_SECTION_NAME (DECL) != NULL_TREE)
175
176 /* Hash table of named sections. */
177 static GTY((param_is (section))) htab_t section_htab;
178
179 /* A table of object_blocks, indexed by section. */
180 static GTY((param_is (struct object_block))) htab_t object_block_htab;
181
182 /* The next number to use for internal anchor labels. */
183 static GTY(()) int anchor_labelno;
184
185 /* A pool of constants that can be shared between functions. */
186 static GTY(()) struct rtx_constant_pool *shared_constant_pool;
187
188 /* Helper routines for maintaining section_htab. */
189
190 static int
191 section_entry_eq (const void *p1, const void *p2)
192 {
193 const section *old = (const section *) p1;
194 const char *new_name = (const char *) p2;
195
196 return strcmp (old->named.name, new_name) == 0;
197 }
198
199 static hashval_t
200 section_entry_hash (const void *p)
201 {
202 const section *old = (const section *) p;
203 return htab_hash_string (old->named.name);
204 }
205
206 /* Return a hash value for section SECT. */
207
208 static hashval_t
209 hash_section (section *sect)
210 {
211 if (sect->common.flags & SECTION_NAMED)
212 return htab_hash_string (sect->named.name);
213 return sect->common.flags;
214 }
215
216 /* Helper routines for maintaining object_block_htab. */
217
218 static int
219 object_block_entry_eq (const void *p1, const void *p2)
220 {
221 const struct object_block *old = (const struct object_block *) p1;
222 const section *new_section = (const section *) p2;
223
224 return old->sect == new_section;
225 }
226
227 static hashval_t
228 object_block_entry_hash (const void *p)
229 {
230 const struct object_block *old = (const struct object_block *) p;
231 return hash_section (old->sect);
232 }
233
234 /* Return a new unnamed section with the given fields. */
235
236 section *
237 get_unnamed_section (unsigned int flags, void (*callback) (const void *),
238 const void *data)
239 {
240 section *sect;
241
242 sect = ggc_alloc_section ();
243 sect->unnamed.common.flags = flags | SECTION_UNNAMED;
244 sect->unnamed.callback = callback;
245 sect->unnamed.data = data;
246 sect->unnamed.next = unnamed_sections;
247
248 unnamed_sections = sect;
249 return sect;
250 }
251
252 /* Return a SECTION_NOSWITCH section with the given fields. */
253
254 static section *
255 get_noswitch_section (unsigned int flags, noswitch_section_callback callback)
256 {
257 section *sect;
258
259 sect = ggc_alloc_section ();
260 sect->noswitch.common.flags = flags | SECTION_NOSWITCH;
261 sect->noswitch.callback = callback;
262
263 return sect;
264 }
265
266 /* Return the named section structure associated with NAME. Create
267 a new section with the given fields if no such structure exists. */
268
269 section *
270 get_section (const char *name, unsigned int flags, tree decl)
271 {
272 section *sect, **slot;
273
274 slot = (section **)
275 htab_find_slot_with_hash (section_htab, name,
276 htab_hash_string (name), INSERT);
277 flags |= SECTION_NAMED;
278 if (*slot == NULL)
279 {
280 sect = ggc_alloc_section ();
281 sect->named.common.flags = flags;
282 sect->named.name = ggc_strdup (name);
283 sect->named.decl = decl;
284 *slot = sect;
285 }
286 else
287 {
288 sect = *slot;
289 if ((sect->common.flags & ~SECTION_DECLARED) != flags
290 && ((sect->common.flags | flags) & SECTION_OVERRIDE) == 0)
291 {
292 /* It is fine if one of the section flags is
293 SECTION_WRITE | SECTION_RELRO and the other has none of these
294 flags (i.e. read-only) in named sections and either the
295 section hasn't been declared yet or has been declared as writable.
296 In that case just make sure the resulting flags are
297 SECTION_WRITE | SECTION_RELRO, ie. writable only because of
298 relocations. */
299 if (((sect->common.flags ^ flags) & (SECTION_WRITE | SECTION_RELRO))
300 == (SECTION_WRITE | SECTION_RELRO)
301 && (sect->common.flags
302 & ~(SECTION_DECLARED | SECTION_WRITE | SECTION_RELRO))
303 == (flags & ~(SECTION_WRITE | SECTION_RELRO))
304 && ((sect->common.flags & SECTION_DECLARED) == 0
305 || (sect->common.flags & SECTION_WRITE)))
306 {
307 sect->common.flags |= (SECTION_WRITE | SECTION_RELRO);
308 return sect;
309 }
310 /* Sanity check user variables for flag changes. */
311 if (sect->named.decl != NULL
312 && DECL_P (sect->named.decl)
313 && decl != sect->named.decl)
314 {
315 if (decl != NULL && DECL_P (decl))
316 error ("%+D causes a section type conflict with %D",
317 decl, sect->named.decl);
318 else
319 error ("section type conflict with %D", sect->named.decl);
320 inform (DECL_SOURCE_LOCATION (sect->named.decl),
321 "%qD was declared here", sect->named.decl);
322 }
323 else if (decl != NULL && DECL_P (decl))
324 error ("%+D causes a section type conflict", decl);
325 else
326 error ("section type conflict");
327 /* Make sure we don't error about one section multiple times. */
328 sect->common.flags |= SECTION_OVERRIDE;
329 }
330 }
331 return sect;
332 }
333
334 /* Return true if the current compilation mode benefits from having
335 objects grouped into blocks. */
336
337 static bool
338 use_object_blocks_p (void)
339 {
340 return flag_section_anchors;
341 }
342
343 /* Return the object_block structure for section SECT. Create a new
344 structure if we haven't created one already. Return null if SECT
345 itself is null. */
346
347 static struct object_block *
348 get_block_for_section (section *sect)
349 {
350 struct object_block *block;
351 void **slot;
352
353 if (sect == NULL)
354 return NULL;
355
356 slot = htab_find_slot_with_hash (object_block_htab, sect,
357 hash_section (sect), INSERT);
358 block = (struct object_block *) *slot;
359 if (block == NULL)
360 {
361 block = ggc_alloc_cleared_object_block ();
362 block->sect = sect;
363 *slot = block;
364 }
365 return block;
366 }
367
368 /* Create a symbol with label LABEL and place it at byte offset
369 OFFSET in BLOCK. OFFSET can be negative if the symbol's offset
370 is not yet known. LABEL must be a garbage-collected string. */
371
372 static rtx
373 create_block_symbol (const char *label, struct object_block *block,
374 HOST_WIDE_INT offset)
375 {
376 rtx symbol;
377 unsigned int size;
378
379 /* Create the extended SYMBOL_REF. */
380 size = RTX_HDR_SIZE + sizeof (struct block_symbol);
381 symbol = ggc_alloc_rtx_def (size);
382
383 /* Initialize the normal SYMBOL_REF fields. */
384 memset (symbol, 0, size);
385 PUT_CODE (symbol, SYMBOL_REF);
386 PUT_MODE (symbol, Pmode);
387 XSTR (symbol, 0) = label;
388 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_HAS_BLOCK_INFO;
389
390 /* Initialize the block_symbol stuff. */
391 SYMBOL_REF_BLOCK (symbol) = block;
392 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
393
394 return symbol;
395 }
396
397 /* Return a section with a particular name and with whatever SECTION_*
398 flags section_type_flags deems appropriate. The name of the section
399 is taken from NAME if nonnull, otherwise it is taken from DECL's
400 DECL_SECTION_NAME. DECL is the decl associated with the section
401 (see the section comment for details) and RELOC is as for
402 section_type_flags. */
403
404 section *
405 get_named_section (tree decl, const char *name, int reloc)
406 {
407 unsigned int flags;
408
409 if (name == NULL)
410 {
411 gcc_assert (decl && DECL_P (decl) && DECL_SECTION_NAME (decl));
412 name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
413 }
414
415 flags = targetm.section_type_flags (decl, name, reloc);
416 return get_section (name, flags, decl);
417 }
418
419 /* If required, set DECL_SECTION_NAME to a unique name. */
420
421 void
422 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
423 int flag_function_or_data_sections)
424 {
425 if (DECL_SECTION_NAME (decl) == NULL_TREE
426 && targetm_common.have_named_sections
427 && (flag_function_or_data_sections
428 || DECL_ONE_ONLY (decl)))
429 {
430 targetm.asm_out.unique_section (decl, reloc);
431 DECL_HAS_IMPLICIT_SECTION_NAME_P (decl) = true;
432 }
433 }
434
435 #ifdef BSS_SECTION_ASM_OP
436
437 #ifdef ASM_OUTPUT_ALIGNED_BSS
438
439 /* Utility function for targets to use in implementing
440 ASM_OUTPUT_ALIGNED_BSS.
441 ??? It is believed that this function will work in most cases so such
442 support is localized here. */
443
444 static void
445 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
446 const char *name, unsigned HOST_WIDE_INT size,
447 int align)
448 {
449 switch_to_section (bss_section);
450 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
451 #ifdef ASM_DECLARE_OBJECT_NAME
452 last_assemble_variable_decl = decl;
453 ASM_DECLARE_OBJECT_NAME (file, name, decl);
454 #else
455 /* Standard thing is just output label for the object. */
456 ASM_OUTPUT_LABEL (file, name);
457 #endif /* ASM_DECLARE_OBJECT_NAME */
458 ASM_OUTPUT_SKIP (file, size ? size : 1);
459 }
460
461 #endif
462
463 #endif /* BSS_SECTION_ASM_OP */
464
465 #ifndef USE_SELECT_SECTION_FOR_FUNCTIONS
466 /* Return the hot section for function DECL. Return text_section for
467 null DECLs. */
468
469 static section *
470 hot_function_section (tree decl)
471 {
472 if (decl != NULL_TREE
473 && DECL_SECTION_NAME (decl) != NULL_TREE
474 && targetm_common.have_named_sections)
475 return get_named_section (decl, NULL, 0);
476 else
477 return text_section;
478 }
479 #endif
480
481 /* Return section for TEXT_SECTION_NAME if DECL or DECL_SECTION_NAME (DECL)
482 is NULL.
483
484 When DECL_SECTION_NAME is non-NULL and it is implicit section and
485 NAMED_SECTION_SUFFIX is non-NULL, then produce section called
486 concatenate the name with NAMED_SECTION_SUFFIX.
487 Otherwise produce "TEXT_SECTION_NAME.IMPLICIT_NAME". */
488
489 section *
490 get_named_text_section (tree decl,
491 const char *text_section_name,
492 const char *named_section_suffix)
493 {
494 if (decl && DECL_SECTION_NAME (decl))
495 {
496 if (named_section_suffix)
497 {
498 tree dsn = DECL_SECTION_NAME (decl);
499 const char *stripped_name;
500 char *name, *buffer;
501
502 name = (char *) alloca (TREE_STRING_LENGTH (dsn) + 1);
503 memcpy (name, TREE_STRING_POINTER (dsn),
504 TREE_STRING_LENGTH (dsn) + 1);
505
506 stripped_name = targetm.strip_name_encoding (name);
507
508 buffer = ACONCAT ((stripped_name, named_section_suffix, NULL));
509 return get_named_section (decl, buffer, 0);
510 }
511 else if (DECL_HAS_IMPLICIT_SECTION_NAME_P (decl))
512 {
513 const char *name;
514
515 /* Do not try to split gnu_linkonce functions. This gets somewhat
516 slipperly. */
517 if (DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP)
518 return NULL;
519 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
520 name = targetm.strip_name_encoding (name);
521 return get_named_section (decl, ACONCAT ((text_section_name, ".",
522 name, NULL)), 0);
523 }
524 else
525 return NULL;
526 }
527 return get_named_section (decl, text_section_name, 0);
528 }
529
530 /* Choose named function section based on its frequency. */
531
532 section *
533 default_function_section (tree decl, enum node_frequency freq,
534 bool startup, bool exit)
535 {
536 #if defined HAVE_LD_EH_GC_SECTIONS && defined HAVE_LD_EH_GC_SECTIONS_BUG
537 /* Old GNU linkers have buggy --gc-section support, which sometimes
538 results in .gcc_except_table* sections being garbage collected. */
539 if (decl
540 && DECL_SECTION_NAME (decl)
541 && DECL_HAS_IMPLICIT_SECTION_NAME_P (decl))
542 return NULL;
543 #endif
544
545 if (!flag_reorder_functions
546 || !targetm_common.have_named_sections)
547 return NULL;
548 /* Startup code should go to startup subsection unless it is
549 unlikely executed (this happens especially with function splitting
550 where we can split away unnecessary parts of static constructors. */
551 if (startup && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
552 return get_named_text_section (decl, ".text.startup", NULL);
553
554 /* Similarly for exit. */
555 if (exit && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
556 return get_named_text_section (decl, ".text.exit", NULL);
557
558 /* Group cold functions together, similarly for hot code. */
559 switch (freq)
560 {
561 case NODE_FREQUENCY_UNLIKELY_EXECUTED:
562 return get_named_text_section (decl, ".text.unlikely", NULL);
563 case NODE_FREQUENCY_HOT:
564 return get_named_text_section (decl, ".text.hot", NULL);
565 default:
566 return NULL;
567 }
568 }
569
570 /* Return the section for function DECL.
571
572 If DECL is NULL_TREE, return the text section. We can be passed
573 NULL_TREE under some circumstances by dbxout.c at least.
574
575 If FORCE_COLD is true, return cold function section ignoring
576 the frequency info of cgraph_node. */
577
578 static section *
579 function_section_1 (tree decl, bool force_cold)
580 {
581 section *section = NULL;
582 enum node_frequency freq = NODE_FREQUENCY_NORMAL;
583 bool startup = false, exit = false;
584
585 if (decl)
586 {
587 struct cgraph_node *node = cgraph_get_node (decl);
588
589 if (node)
590 {
591 freq = node->frequency;
592 startup = node->only_called_at_startup;
593 exit = node->only_called_at_exit;
594 }
595 }
596 if (force_cold)
597 freq = NODE_FREQUENCY_UNLIKELY_EXECUTED;
598
599 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
600 if (decl != NULL_TREE
601 && DECL_SECTION_NAME (decl) != NULL_TREE)
602 {
603 if (targetm.asm_out.function_section)
604 section = targetm.asm_out.function_section (decl, freq,
605 startup, exit);
606 if (section)
607 return section;
608 return get_named_section (decl, NULL, 0);
609 }
610 else
611 return targetm.asm_out.select_section
612 (decl, freq == NODE_FREQUENCY_UNLIKELY_EXECUTED,
613 DECL_ALIGN (decl));
614 #else
615 if (targetm.asm_out.function_section)
616 section = targetm.asm_out.function_section (decl, freq, startup, exit);
617 if (section)
618 return section;
619 return hot_function_section (decl);
620 #endif
621 }
622
623 /* Return the section for function DECL.
624
625 If DECL is NULL_TREE, return the text section. We can be passed
626 NULL_TREE under some circumstances by dbxout.c at least. */
627
628 section *
629 function_section (tree decl)
630 {
631 /* Handle cases where function splitting code decides
632 to put function entry point into unlikely executed section
633 despite the fact that the function itself is not cold
634 (i.e. it is called rarely but contains a hot loop that is
635 better to live in hot subsection for the code locality). */
636 return function_section_1 (decl,
637 first_function_block_is_cold);
638 }
639
640 /* Return the section for the current function, take IN_COLD_SECTION_P
641 into account. */
642
643 section *
644 current_function_section (void)
645 {
646 return function_section_1 (current_function_decl, in_cold_section_p);
647 }
648
649 /* Tell assembler to switch to unlikely-to-be-executed text section. */
650
651 section *
652 unlikely_text_section (void)
653 {
654 return function_section_1 (current_function_decl, true);
655 }
656
657 /* When called within a function context, return true if the function
658 has been assigned a cold text section and if SECT is that section.
659 When called outside a function context, return true if SECT is the
660 default cold section. */
661
662 bool
663 unlikely_text_section_p (section *sect)
664 {
665 return sect == function_section_1 (current_function_decl, true);
666 }
667
668 /* Return the read-only data section associated with function DECL. */
669
670 section *
671 default_function_rodata_section (tree decl)
672 {
673 if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
674 {
675 const char *name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
676
677 if (DECL_ONE_ONLY (decl) && HAVE_COMDAT_GROUP)
678 {
679 const char *dot;
680 size_t len;
681 char* rname;
682
683 dot = strchr (name + 1, '.');
684 if (!dot)
685 dot = name;
686 len = strlen (dot) + 8;
687 rname = (char *) alloca (len);
688
689 strcpy (rname, ".rodata");
690 strcat (rname, dot);
691 return get_section (rname, SECTION_LINKONCE, decl);
692 }
693 /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo. */
694 else if (DECL_ONE_ONLY (decl)
695 && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
696 {
697 size_t len = strlen (name) + 1;
698 char *rname = (char *) alloca (len);
699
700 memcpy (rname, name, len);
701 rname[14] = 'r';
702 return get_section (rname, SECTION_LINKONCE, decl);
703 }
704 /* For .text.foo we want to use .rodata.foo. */
705 else if (flag_function_sections && flag_data_sections
706 && strncmp (name, ".text.", 6) == 0)
707 {
708 size_t len = strlen (name) + 1;
709 char *rname = (char *) alloca (len + 2);
710
711 memcpy (rname, ".rodata", 7);
712 memcpy (rname + 7, name + 5, len - 5);
713 return get_section (rname, 0, decl);
714 }
715 }
716
717 return readonly_data_section;
718 }
719
720 /* Return the read-only data section associated with function DECL
721 for targets where that section should be always the single
722 readonly data section. */
723
724 section *
725 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
726 {
727 return readonly_data_section;
728 }
729
730 /* Return the section to use for string merging. */
731
732 static section *
733 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
734 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
735 unsigned int flags ATTRIBUTE_UNUSED)
736 {
737 HOST_WIDE_INT len;
738
739 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
740 && TREE_CODE (decl) == STRING_CST
741 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
742 && align <= 256
743 && (len = int_size_in_bytes (TREE_TYPE (decl))) > 0
744 && TREE_STRING_LENGTH (decl) >= len)
745 {
746 enum machine_mode mode;
747 unsigned int modesize;
748 const char *str;
749 HOST_WIDE_INT i;
750 int j, unit;
751 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
752 char *name = (char *) alloca (strlen (prefix) + 30);
753
754 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
755 modesize = GET_MODE_BITSIZE (mode);
756 if (modesize >= 8 && modesize <= 256
757 && (modesize & (modesize - 1)) == 0)
758 {
759 if (align < modesize)
760 align = modesize;
761
762 str = TREE_STRING_POINTER (decl);
763 unit = GET_MODE_SIZE (mode);
764
765 /* Check for embedded NUL characters. */
766 for (i = 0; i < len; i += unit)
767 {
768 for (j = 0; j < unit; j++)
769 if (str[i + j] != '\0')
770 break;
771 if (j == unit)
772 break;
773 }
774 if (i == len - unit)
775 {
776 sprintf (name, "%s.str%d.%d", prefix,
777 modesize / 8, (int) (align / 8));
778 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
779 return get_section (name, flags, NULL);
780 }
781 }
782 }
783
784 return readonly_data_section;
785 }
786
787 /* Return the section to use for constant merging. */
788
789 section *
790 mergeable_constant_section (enum machine_mode mode ATTRIBUTE_UNUSED,
791 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
792 unsigned int flags ATTRIBUTE_UNUSED)
793 {
794 unsigned int modesize = GET_MODE_BITSIZE (mode);
795
796 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
797 && mode != VOIDmode
798 && mode != BLKmode
799 && modesize <= align
800 && align >= 8
801 && align <= 256
802 && (align & (align - 1)) == 0)
803 {
804 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
805 char *name = (char *) alloca (strlen (prefix) + 30);
806
807 sprintf (name, "%s.cst%d", prefix, (int) (align / 8));
808 flags |= (align / 8) | SECTION_MERGE;
809 return get_section (name, flags, NULL);
810 }
811 return readonly_data_section;
812 }
813 \f
814 /* Given NAME, a putative register name, discard any customary prefixes. */
815
816 static const char *
817 strip_reg_name (const char *name)
818 {
819 #ifdef REGISTER_PREFIX
820 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
821 name += strlen (REGISTER_PREFIX);
822 #endif
823 if (name[0] == '%' || name[0] == '#')
824 name++;
825 return name;
826 }
827 \f
828 /* The user has asked for a DECL to have a particular name. Set (or
829 change) it in such a way that we don't prefix an underscore to
830 it. */
831 void
832 set_user_assembler_name (tree decl, const char *name)
833 {
834 char *starred = (char *) alloca (strlen (name) + 2);
835 starred[0] = '*';
836 strcpy (starred + 1, name);
837 change_decl_assembler_name (decl, get_identifier (starred));
838 SET_DECL_RTL (decl, NULL_RTX);
839 }
840 \f
841 /* Decode an `asm' spec for a declaration as a register name.
842 Return the register number, or -1 if nothing specified,
843 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
844 or -3 if ASMSPEC is `cc' and is not recognized,
845 or -4 if ASMSPEC is `memory' and is not recognized.
846 Accept an exact spelling or a decimal number.
847 Prefixes such as % are optional. */
848
849 int
850 decode_reg_name_and_count (const char *asmspec, int *pnregs)
851 {
852 /* Presume just one register is clobbered. */
853 *pnregs = 1;
854
855 if (asmspec != 0)
856 {
857 int i;
858
859 /* Get rid of confusing prefixes. */
860 asmspec = strip_reg_name (asmspec);
861
862 /* Allow a decimal number as a "register name". */
863 for (i = strlen (asmspec) - 1; i >= 0; i--)
864 if (! ISDIGIT (asmspec[i]))
865 break;
866 if (asmspec[0] != 0 && i < 0)
867 {
868 i = atoi (asmspec);
869 if (i < FIRST_PSEUDO_REGISTER && i >= 0)
870 return i;
871 else
872 return -2;
873 }
874
875 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
876 if (reg_names[i][0]
877 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
878 return i;
879
880 #ifdef OVERLAPPING_REGISTER_NAMES
881 {
882 static const struct
883 {
884 const char *const name;
885 const int number;
886 const int nregs;
887 } table[] = OVERLAPPING_REGISTER_NAMES;
888
889 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
890 if (table[i].name[0]
891 && ! strcmp (asmspec, table[i].name))
892 {
893 *pnregs = table[i].nregs;
894 return table[i].number;
895 }
896 }
897 #endif /* OVERLAPPING_REGISTER_NAMES */
898
899 #ifdef ADDITIONAL_REGISTER_NAMES
900 {
901 static const struct { const char *const name; const int number; } table[]
902 = ADDITIONAL_REGISTER_NAMES;
903
904 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
905 if (table[i].name[0]
906 && ! strcmp (asmspec, table[i].name))
907 return table[i].number;
908 }
909 #endif /* ADDITIONAL_REGISTER_NAMES */
910
911 if (!strcmp (asmspec, "memory"))
912 return -4;
913
914 if (!strcmp (asmspec, "cc"))
915 return -3;
916
917 return -2;
918 }
919
920 return -1;
921 }
922
923 int
924 decode_reg_name (const char *name)
925 {
926 int count;
927 return decode_reg_name_and_count (name, &count);
928 }
929
930 \f
931 /* Return true if DECL's initializer is suitable for a BSS section. */
932
933 bool
934 bss_initializer_p (const_tree decl)
935 {
936 return (DECL_INITIAL (decl) == NULL
937 || DECL_INITIAL (decl) == error_mark_node
938 || (flag_zero_initialized_in_bss
939 /* Leave constant zeroes in .rodata so they
940 can be shared. */
941 && !TREE_READONLY (decl)
942 && initializer_zerop (DECL_INITIAL (decl))));
943 }
944
945 /* Compute the alignment of variable specified by DECL.
946 DONT_OUTPUT_DATA is from assemble_variable. */
947
948 void
949 align_variable (tree decl, bool dont_output_data)
950 {
951 unsigned int align = DECL_ALIGN (decl);
952
953 /* In the case for initialing an array whose length isn't specified,
954 where we have not yet been able to do the layout,
955 figure out the proper alignment now. */
956 if (dont_output_data && DECL_SIZE (decl) == 0
957 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
958 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
959
960 /* Some object file formats have a maximum alignment which they support.
961 In particular, a.out format supports a maximum alignment of 4. */
962 if (align > MAX_OFILE_ALIGNMENT)
963 {
964 warning (0, "alignment of %q+D is greater than maximum object "
965 "file alignment. Using %d", decl,
966 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
967 align = MAX_OFILE_ALIGNMENT;
968 }
969
970 if (! DECL_USER_ALIGN (decl))
971 {
972 #ifdef DATA_ABI_ALIGNMENT
973 unsigned int data_abi_align
974 = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
975 /* For backwards compatibility, don't assume the ABI alignment for
976 TLS variables. */
977 if (! DECL_THREAD_LOCAL_P (decl) || data_abi_align <= BITS_PER_WORD)
978 align = data_abi_align;
979 #endif
980
981 /* On some machines, it is good to increase alignment sometimes.
982 But as DECL_ALIGN is used both for actually emitting the variable
983 and for code accessing the variable as guaranteed alignment, we
984 can only increase the alignment if it is a performance optimization
985 if the references to it must bind to the current definition. */
986 if (decl_binds_to_current_def_p (decl))
987 {
988 #ifdef DATA_ALIGNMENT
989 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
990 /* Don't increase alignment too much for TLS variables - TLS space
991 is too precious. */
992 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
993 align = data_align;
994 #endif
995 #ifdef CONSTANT_ALIGNMENT
996 if (DECL_INITIAL (decl) != 0
997 && DECL_INITIAL (decl) != error_mark_node)
998 {
999 unsigned int const_align
1000 = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
1001 /* Don't increase alignment too much for TLS variables - TLS
1002 space is too precious. */
1003 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1004 align = const_align;
1005 }
1006 #endif
1007 }
1008 }
1009
1010 /* Reset the alignment in case we have made it tighter, so we can benefit
1011 from it in get_pointer_alignment. */
1012 DECL_ALIGN (decl) = align;
1013 }
1014
1015 /* Return DECL_ALIGN (decl), possibly increased for optimization purposes
1016 beyond what align_variable returned. */
1017
1018 static unsigned int
1019 get_variable_align (tree decl)
1020 {
1021 unsigned int align = DECL_ALIGN (decl);
1022
1023 /* For user aligned vars or static vars align_variable already did
1024 everything. */
1025 if (DECL_USER_ALIGN (decl) || !TREE_PUBLIC (decl))
1026 return align;
1027
1028 #ifdef DATA_ABI_ALIGNMENT
1029 if (DECL_THREAD_LOCAL_P (decl))
1030 align = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1031 #endif
1032
1033 /* For decls that bind to the current definition, align_variable
1034 did also everything, except for not assuming ABI required alignment
1035 of TLS variables. For other vars, increase the alignment here
1036 as an optimization. */
1037 if (!decl_binds_to_current_def_p (decl))
1038 {
1039 /* On some machines, it is good to increase alignment sometimes. */
1040 #ifdef DATA_ALIGNMENT
1041 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1042 /* Don't increase alignment too much for TLS variables - TLS space
1043 is too precious. */
1044 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1045 align = data_align;
1046 #endif
1047 #ifdef CONSTANT_ALIGNMENT
1048 if (DECL_INITIAL (decl) != 0 && DECL_INITIAL (decl) != error_mark_node)
1049 {
1050 unsigned int const_align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl),
1051 align);
1052 /* Don't increase alignment too much for TLS variables - TLS space
1053 is too precious. */
1054 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1055 align = const_align;
1056 }
1057 #endif
1058 }
1059
1060 return align;
1061 }
1062
1063 /* Return the section into which the given VAR_DECL or CONST_DECL
1064 should be placed. PREFER_NOSWITCH_P is true if a noswitch
1065 section should be used wherever possible. */
1066
1067 section *
1068 get_variable_section (tree decl, bool prefer_noswitch_p)
1069 {
1070 addr_space_t as = ADDR_SPACE_GENERIC;
1071 int reloc;
1072
1073 if (TREE_TYPE (decl) != error_mark_node)
1074 as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1075
1076 if (DECL_COMMON (decl))
1077 {
1078 /* If the decl has been given an explicit section name, or it resides
1079 in a non-generic address space, then it isn't common, and shouldn't
1080 be handled as such. */
1081 gcc_assert (DECL_SECTION_NAME (decl) == NULL
1082 && ADDR_SPACE_GENERIC_P (as));
1083 if (DECL_THREAD_LOCAL_P (decl))
1084 return tls_comm_section;
1085 else if (TREE_PUBLIC (decl) && bss_initializer_p (decl))
1086 return comm_section;
1087 }
1088
1089 if (DECL_INITIAL (decl) == error_mark_node)
1090 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1091 else if (DECL_INITIAL (decl))
1092 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1093 else
1094 reloc = 0;
1095
1096 resolve_unique_section (decl, reloc, flag_data_sections);
1097 if (IN_NAMED_SECTION (decl))
1098 return get_named_section (decl, NULL, reloc);
1099
1100 if (ADDR_SPACE_GENERIC_P (as)
1101 && !DECL_THREAD_LOCAL_P (decl)
1102 && !(prefer_noswitch_p && targetm.have_switchable_bss_sections)
1103 && bss_initializer_p (decl))
1104 {
1105 if (!TREE_PUBLIC (decl)
1106 && !((flag_sanitize & SANITIZE_ADDRESS)
1107 && asan_protect_global (decl)))
1108 return lcomm_section;
1109 if (bss_noswitch_section)
1110 return bss_noswitch_section;
1111 }
1112
1113 return targetm.asm_out.select_section (decl, reloc,
1114 get_variable_align (decl));
1115 }
1116
1117 /* Return the block into which object_block DECL should be placed. */
1118
1119 static struct object_block *
1120 get_block_for_decl (tree decl)
1121 {
1122 section *sect;
1123
1124 if (TREE_CODE (decl) == VAR_DECL)
1125 {
1126 /* The object must be defined in this translation unit. */
1127 if (DECL_EXTERNAL (decl))
1128 return NULL;
1129
1130 /* There's no point using object blocks for something that is
1131 isolated by definition. */
1132 if (DECL_ONE_ONLY (decl))
1133 return NULL;
1134 }
1135
1136 /* We can only calculate block offsets if the decl has a known
1137 constant size. */
1138 if (DECL_SIZE_UNIT (decl) == NULL)
1139 return NULL;
1140 if (!host_integerp (DECL_SIZE_UNIT (decl), 1))
1141 return NULL;
1142
1143 /* Find out which section should contain DECL. We cannot put it into
1144 an object block if it requires a standalone definition. */
1145 if (TREE_CODE (decl) == VAR_DECL)
1146 align_variable (decl, 0);
1147 sect = get_variable_section (decl, true);
1148 if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
1149 return NULL;
1150
1151 return get_block_for_section (sect);
1152 }
1153
1154 /* Make sure block symbol SYMBOL is in block BLOCK. */
1155
1156 static void
1157 change_symbol_block (rtx symbol, struct object_block *block)
1158 {
1159 if (block != SYMBOL_REF_BLOCK (symbol))
1160 {
1161 gcc_assert (SYMBOL_REF_BLOCK_OFFSET (symbol) < 0);
1162 SYMBOL_REF_BLOCK (symbol) = block;
1163 }
1164 }
1165
1166 /* Return true if it is possible to put DECL in an object_block. */
1167
1168 static bool
1169 use_blocks_for_decl_p (tree decl)
1170 {
1171 /* Only data DECLs can be placed into object blocks. */
1172 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != CONST_DECL)
1173 return false;
1174
1175 /* Detect decls created by dw2_force_const_mem. Such decls are
1176 special because DECL_INITIAL doesn't specify the decl's true value.
1177 dw2_output_indirect_constants will instead call assemble_variable
1178 with dont_output_data set to 1 and then print the contents itself. */
1179 if (DECL_INITIAL (decl) == decl)
1180 return false;
1181
1182 /* If this decl is an alias, then we don't want to emit a
1183 definition. */
1184 if (lookup_attribute ("alias", DECL_ATTRIBUTES (decl)))
1185 return false;
1186
1187 return targetm.use_blocks_for_decl_p (decl);
1188 }
1189
1190 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
1191 have static storage duration. In other words, it should not be an
1192 automatic variable, including PARM_DECLs.
1193
1194 There is, however, one exception: this function handles variables
1195 explicitly placed in a particular register by the user.
1196
1197 This is never called for PARM_DECL nodes. */
1198
1199 void
1200 make_decl_rtl (tree decl)
1201 {
1202 const char *name = 0;
1203 int reg_number;
1204 rtx x;
1205
1206 /* Check that we are not being given an automatic variable. */
1207 gcc_assert (TREE_CODE (decl) != PARM_DECL
1208 && TREE_CODE (decl) != RESULT_DECL);
1209
1210 /* A weak alias has TREE_PUBLIC set but not the other bits. */
1211 gcc_assert (TREE_CODE (decl) != VAR_DECL
1212 || TREE_STATIC (decl)
1213 || TREE_PUBLIC (decl)
1214 || DECL_EXTERNAL (decl)
1215 || DECL_REGISTER (decl));
1216
1217 /* And that we were not given a type or a label. */
1218 gcc_assert (TREE_CODE (decl) != TYPE_DECL
1219 && TREE_CODE (decl) != LABEL_DECL);
1220
1221 /* For a duplicate declaration, we can be called twice on the
1222 same DECL node. Don't discard the RTL already made. */
1223 if (DECL_RTL_SET_P (decl))
1224 {
1225 /* If the old RTL had the wrong mode, fix the mode. */
1226 x = DECL_RTL (decl);
1227 if (GET_MODE (x) != DECL_MODE (decl))
1228 SET_DECL_RTL (decl, adjust_address_nv (x, DECL_MODE (decl), 0));
1229
1230 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1231 return;
1232
1233 /* ??? Another way to do this would be to maintain a hashed
1234 table of such critters. Instead of adding stuff to a DECL
1235 to give certain attributes to it, we could use an external
1236 hash map from DECL to set of attributes. */
1237
1238 /* Let the target reassign the RTL if it wants.
1239 This is necessary, for example, when one machine specific
1240 decl attribute overrides another. */
1241 targetm.encode_section_info (decl, DECL_RTL (decl), false);
1242
1243 /* If the symbol has a SYMBOL_REF_BLOCK field, update it based
1244 on the new decl information. */
1245 if (MEM_P (x)
1246 && GET_CODE (XEXP (x, 0)) == SYMBOL_REF
1247 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (x, 0)))
1248 change_symbol_block (XEXP (x, 0), get_block_for_decl (decl));
1249
1250 /* Make this function static known to the mudflap runtime. */
1251 if (flag_mudflap && TREE_CODE (decl) == VAR_DECL)
1252 mudflap_enqueue_decl (decl);
1253
1254 return;
1255 }
1256
1257 /* If this variable belongs to the global constant pool, retrieve the
1258 pre-computed RTL or recompute it in LTO mode. */
1259 if (TREE_CODE (decl) == VAR_DECL && DECL_IN_CONSTANT_POOL (decl))
1260 {
1261 SET_DECL_RTL (decl, output_constant_def (DECL_INITIAL (decl), 1));
1262 return;
1263 }
1264
1265 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
1266
1267 if (name[0] != '*' && TREE_CODE (decl) != FUNCTION_DECL
1268 && DECL_REGISTER (decl))
1269 {
1270 error ("register name not specified for %q+D", decl);
1271 }
1272 else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1273 {
1274 const char *asmspec = name+1;
1275 enum machine_mode mode = DECL_MODE (decl);
1276 reg_number = decode_reg_name (asmspec);
1277 /* First detect errors in declaring global registers. */
1278 if (reg_number == -1)
1279 error ("register name not specified for %q+D", decl);
1280 else if (reg_number < 0)
1281 error ("invalid register name for %q+D", decl);
1282 else if (mode == BLKmode)
1283 error ("data type of %q+D isn%'t suitable for a register",
1284 decl);
1285 else if (!in_hard_reg_set_p (accessible_reg_set, mode, reg_number))
1286 error ("the register specified for %q+D cannot be accessed"
1287 " by the current target", decl);
1288 else if (!in_hard_reg_set_p (operand_reg_set, mode, reg_number))
1289 error ("the register specified for %q+D is not general enough"
1290 " to be used as a register variable", decl);
1291 else if (!HARD_REGNO_MODE_OK (reg_number, mode))
1292 error ("register specified for %q+D isn%'t suitable for data type",
1293 decl);
1294 /* Now handle properly declared static register variables. */
1295 else
1296 {
1297 int nregs;
1298
1299 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
1300 {
1301 DECL_INITIAL (decl) = 0;
1302 error ("global register variable has initial value");
1303 }
1304 if (TREE_THIS_VOLATILE (decl))
1305 warning (OPT_Wvolatile_register_var,
1306 "optimization may eliminate reads and/or "
1307 "writes to register variables");
1308
1309 /* If the user specified one of the eliminables registers here,
1310 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
1311 confused with that register and be eliminated. This usage is
1312 somewhat suspect... */
1313
1314 SET_DECL_RTL (decl, gen_rtx_raw_REG (mode, reg_number));
1315 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
1316 REG_USERVAR_P (DECL_RTL (decl)) = 1;
1317
1318 if (TREE_STATIC (decl))
1319 {
1320 /* Make this register global, so not usable for anything
1321 else. */
1322 #ifdef ASM_DECLARE_REGISTER_GLOBAL
1323 name = IDENTIFIER_POINTER (DECL_NAME (decl));
1324 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
1325 #endif
1326 nregs = hard_regno_nregs[reg_number][mode];
1327 while (nregs > 0)
1328 globalize_reg (decl, reg_number + --nregs);
1329 }
1330
1331 /* As a register variable, it has no section. */
1332 return;
1333 }
1334 }
1335 /* Now handle ordinary static variables and functions (in memory).
1336 Also handle vars declared register invalidly. */
1337 else if (name[0] == '*')
1338 {
1339 #ifdef REGISTER_PREFIX
1340 if (strlen (REGISTER_PREFIX) != 0)
1341 {
1342 reg_number = decode_reg_name (name);
1343 if (reg_number >= 0 || reg_number == -3)
1344 error ("register name given for non-register variable %q+D", decl);
1345 }
1346 #endif
1347 }
1348
1349 /* Specifying a section attribute on a variable forces it into a
1350 non-.bss section, and thus it cannot be common. */
1351 /* FIXME: In general this code should not be necessary because
1352 visibility pass is doing the same work. But notice_global_symbol
1353 is called early and it needs to make DECL_RTL to get the name.
1354 we take care of recomputing the DECL_RTL after visibility is changed. */
1355 if (TREE_CODE (decl) == VAR_DECL
1356 && DECL_SECTION_NAME (decl) != NULL_TREE
1357 && DECL_INITIAL (decl) == NULL_TREE
1358 && DECL_COMMON (decl))
1359 DECL_COMMON (decl) = 0;
1360
1361 /* Variables can't be both common and weak. */
1362 if (TREE_CODE (decl) == VAR_DECL && DECL_WEAK (decl))
1363 DECL_COMMON (decl) = 0;
1364
1365 if (use_object_blocks_p () && use_blocks_for_decl_p (decl))
1366 x = create_block_symbol (name, get_block_for_decl (decl), -1);
1367 else
1368 {
1369 enum machine_mode address_mode = Pmode;
1370 if (TREE_TYPE (decl) != error_mark_node)
1371 {
1372 addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1373 address_mode = targetm.addr_space.address_mode (as);
1374 }
1375 x = gen_rtx_SYMBOL_REF (address_mode, name);
1376 }
1377 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
1378 SET_SYMBOL_REF_DECL (x, decl);
1379
1380 x = gen_rtx_MEM (DECL_MODE (decl), x);
1381 if (TREE_CODE (decl) != FUNCTION_DECL)
1382 set_mem_attributes (x, decl, 1);
1383 SET_DECL_RTL (decl, x);
1384
1385 /* Optionally set flags or add text to the name to record information
1386 such as that it is a function name.
1387 If the name is changed, the macro ASM_OUTPUT_LABELREF
1388 will have to know how to strip this information. */
1389 targetm.encode_section_info (decl, DECL_RTL (decl), true);
1390
1391 /* Make this function static known to the mudflap runtime. */
1392 if (flag_mudflap && TREE_CODE (decl) == VAR_DECL)
1393 mudflap_enqueue_decl (decl);
1394 }
1395
1396 /* Like make_decl_rtl, but inhibit creation of new alias sets when
1397 calling make_decl_rtl. Also, reset DECL_RTL before returning the
1398 rtl. */
1399
1400 rtx
1401 make_decl_rtl_for_debug (tree decl)
1402 {
1403 unsigned int save_aliasing_flag, save_mudflap_flag;
1404 rtx rtl;
1405
1406 if (DECL_RTL_SET_P (decl))
1407 return DECL_RTL (decl);
1408
1409 /* Kludge alert! Somewhere down the call chain, make_decl_rtl will
1410 call new_alias_set. If running with -fcompare-debug, sometimes
1411 we do not want to create alias sets that will throw the alias
1412 numbers off in the comparison dumps. So... clearing
1413 flag_strict_aliasing will keep new_alias_set() from creating a
1414 new set. It is undesirable to register decl with mudflap
1415 in this case as well. */
1416 save_aliasing_flag = flag_strict_aliasing;
1417 flag_strict_aliasing = 0;
1418 save_mudflap_flag = flag_mudflap;
1419 flag_mudflap = 0;
1420
1421 rtl = DECL_RTL (decl);
1422 /* Reset DECL_RTL back, as various parts of the compiler expects
1423 DECL_RTL set meaning it is actually going to be output. */
1424 SET_DECL_RTL (decl, NULL);
1425
1426 flag_strict_aliasing = save_aliasing_flag;
1427 flag_mudflap = save_mudflap_flag;
1428
1429 return rtl;
1430 }
1431 \f
1432 /* Output a string of literal assembler code
1433 for an `asm' keyword used between functions. */
1434
1435 void
1436 assemble_asm (tree string)
1437 {
1438 const char *p;
1439 app_enable ();
1440
1441 if (TREE_CODE (string) == ADDR_EXPR)
1442 string = TREE_OPERAND (string, 0);
1443
1444 p = TREE_STRING_POINTER (string);
1445 fprintf (asm_out_file, "%s%s\n", p[0] == '\t' ? "" : "\t", p);
1446 }
1447
1448 /* Write the address of the entity given by SYMBOL to SEC. */
1449 void
1450 assemble_addr_to_section (rtx symbol, section *sec)
1451 {
1452 switch_to_section (sec);
1453 assemble_align (POINTER_SIZE);
1454 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1455 }
1456
1457 /* Return the numbered .ctors.N (if CONSTRUCTOR_P) or .dtors.N (if
1458 not) section for PRIORITY. */
1459 section *
1460 get_cdtor_priority_section (int priority, bool constructor_p)
1461 {
1462 char buf[16];
1463
1464 /* ??? This only works reliably with the GNU linker. */
1465 sprintf (buf, "%s.%.5u",
1466 constructor_p ? ".ctors" : ".dtors",
1467 /* Invert the numbering so the linker puts us in the proper
1468 order; constructors are run from right to left, and the
1469 linker sorts in increasing order. */
1470 MAX_INIT_PRIORITY - priority);
1471 return get_section (buf, SECTION_WRITE, NULL);
1472 }
1473
1474 void
1475 default_named_section_asm_out_destructor (rtx symbol, int priority)
1476 {
1477 section *sec;
1478
1479 if (priority != DEFAULT_INIT_PRIORITY)
1480 sec = get_cdtor_priority_section (priority,
1481 /*constructor_p=*/false);
1482 else
1483 sec = get_section (".dtors", SECTION_WRITE, NULL);
1484
1485 assemble_addr_to_section (symbol, sec);
1486 }
1487
1488 #ifdef DTORS_SECTION_ASM_OP
1489 void
1490 default_dtor_section_asm_out_destructor (rtx symbol,
1491 int priority ATTRIBUTE_UNUSED)
1492 {
1493 assemble_addr_to_section (symbol, dtors_section);
1494 }
1495 #endif
1496
1497 void
1498 default_named_section_asm_out_constructor (rtx symbol, int priority)
1499 {
1500 section *sec;
1501
1502 if (priority != DEFAULT_INIT_PRIORITY)
1503 sec = get_cdtor_priority_section (priority,
1504 /*constructor_p=*/true);
1505 else
1506 sec = get_section (".ctors", SECTION_WRITE, NULL);
1507
1508 assemble_addr_to_section (symbol, sec);
1509 }
1510
1511 #ifdef CTORS_SECTION_ASM_OP
1512 void
1513 default_ctor_section_asm_out_constructor (rtx symbol,
1514 int priority ATTRIBUTE_UNUSED)
1515 {
1516 assemble_addr_to_section (symbol, ctors_section);
1517 }
1518 #endif
1519 \f
1520 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1521 a nonzero value if the constant pool should be output before the
1522 start of the function, or a zero value if the pool should output
1523 after the end of the function. The default is to put it before the
1524 start. */
1525
1526 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1527 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1528 #endif
1529
1530 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1531 to be output to assembler.
1532 Set first_global_object_name and weak_global_object_name as appropriate. */
1533
1534 void
1535 notice_global_symbol (tree decl)
1536 {
1537 const char **type = &first_global_object_name;
1538
1539 if (first_global_object_name
1540 || !TREE_PUBLIC (decl)
1541 || DECL_EXTERNAL (decl)
1542 || !DECL_NAME (decl)
1543 || (TREE_CODE (decl) != FUNCTION_DECL
1544 && (TREE_CODE (decl) != VAR_DECL
1545 || (DECL_COMMON (decl)
1546 && (DECL_INITIAL (decl) == 0
1547 || DECL_INITIAL (decl) == error_mark_node))))
1548 || !MEM_P (DECL_RTL (decl)))
1549 return;
1550
1551 /* We win when global object is found, but it is useful to know about weak
1552 symbol as well so we can produce nicer unique names. */
1553 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl) || flag_shlib)
1554 type = &weak_global_object_name;
1555
1556 if (!*type)
1557 {
1558 const char *p;
1559 const char *name;
1560 rtx decl_rtl = DECL_RTL (decl);
1561
1562 p = targetm.strip_name_encoding (XSTR (XEXP (decl_rtl, 0), 0));
1563 name = ggc_strdup (p);
1564
1565 *type = name;
1566 }
1567 }
1568
1569 /* If not using flag_reorder_blocks_and_partition, decide early whether the
1570 current function goes into the cold section, so that targets can use
1571 current_function_section during RTL expansion. DECL describes the
1572 function. */
1573
1574 void
1575 decide_function_section (tree decl)
1576 {
1577 first_function_block_is_cold = false;
1578
1579 if (flag_reorder_blocks_and_partition)
1580 /* We will decide in assemble_start_function. */
1581 return;
1582
1583 if (DECL_SECTION_NAME (decl))
1584 {
1585 struct cgraph_node *node = cgraph_get_node (current_function_decl);
1586 /* Calls to function_section rely on first_function_block_is_cold
1587 being accurate. */
1588 first_function_block_is_cold = (node
1589 && node->frequency
1590 == NODE_FREQUENCY_UNLIKELY_EXECUTED);
1591 }
1592
1593 in_cold_section_p = first_function_block_is_cold;
1594 }
1595
1596 /* Output assembler code for the constant pool of a function and associated
1597 with defining the name of the function. DECL describes the function.
1598 NAME is the function's name. For the constant pool, we use the current
1599 constant pool data. */
1600
1601 void
1602 assemble_start_function (tree decl, const char *fnname)
1603 {
1604 int align;
1605 char tmp_label[100];
1606 bool hot_label_written = false;
1607
1608 if (flag_reorder_blocks_and_partition)
1609 {
1610 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTB", const_labelno);
1611 crtl->subsections.hot_section_label = ggc_strdup (tmp_label);
1612 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDB", const_labelno);
1613 crtl->subsections.cold_section_label = ggc_strdup (tmp_label);
1614 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTE", const_labelno);
1615 crtl->subsections.hot_section_end_label = ggc_strdup (tmp_label);
1616 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDE", const_labelno);
1617 crtl->subsections.cold_section_end_label = ggc_strdup (tmp_label);
1618 const_labelno++;
1619 }
1620 else
1621 {
1622 crtl->subsections.hot_section_label = NULL;
1623 crtl->subsections.cold_section_label = NULL;
1624 crtl->subsections.hot_section_end_label = NULL;
1625 crtl->subsections.cold_section_end_label = NULL;
1626 }
1627
1628 /* The following code does not need preprocessing in the assembler. */
1629
1630 app_disable ();
1631
1632 if (CONSTANT_POOL_BEFORE_FUNCTION)
1633 output_constant_pool (fnname, decl);
1634
1635 /* Make sure the not and cold text (code) sections are properly
1636 aligned. This is necessary here in the case where the function
1637 has both hot and cold sections, because we don't want to re-set
1638 the alignment when the section switch happens mid-function. */
1639
1640 if (flag_reorder_blocks_and_partition)
1641 {
1642 first_function_block_is_cold = false;
1643
1644 switch_to_section (unlikely_text_section ());
1645 assemble_align (DECL_ALIGN (decl));
1646 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_label);
1647
1648 /* When the function starts with a cold section, we need to explicitly
1649 align the hot section and write out the hot section label.
1650 But if the current function is a thunk, we do not have a CFG. */
1651 if (!cfun->is_thunk
1652 && BB_PARTITION (ENTRY_BLOCK_PTR->next_bb) == BB_COLD_PARTITION)
1653 {
1654 switch_to_section (text_section);
1655 assemble_align (DECL_ALIGN (decl));
1656 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1657 hot_label_written = true;
1658 first_function_block_is_cold = true;
1659 }
1660 in_cold_section_p = first_function_block_is_cold;
1661 }
1662
1663
1664 /* Switch to the correct text section for the start of the function. */
1665
1666 switch_to_section (function_section (decl));
1667 if (flag_reorder_blocks_and_partition
1668 && !hot_label_written)
1669 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1670
1671 /* Tell assembler to move to target machine's alignment for functions. */
1672 align = floor_log2 (DECL_ALIGN (decl) / BITS_PER_UNIT);
1673 if (align > 0)
1674 {
1675 ASM_OUTPUT_ALIGN (asm_out_file, align);
1676 }
1677
1678 /* Handle a user-specified function alignment.
1679 Note that we still need to align to DECL_ALIGN, as above,
1680 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1681 if (! DECL_USER_ALIGN (decl)
1682 && align_functions_log > align
1683 && optimize_function_for_speed_p (cfun))
1684 {
1685 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1686 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1687 align_functions_log, align_functions - 1);
1688 #else
1689 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1690 #endif
1691 }
1692
1693 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1694 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1695 #endif
1696
1697 if (!DECL_IGNORED_P (decl))
1698 (*debug_hooks->begin_function) (decl);
1699
1700 /* Make function name accessible from other files, if appropriate. */
1701
1702 if (TREE_PUBLIC (decl))
1703 {
1704 notice_global_symbol (decl);
1705
1706 globalize_decl (decl);
1707
1708 maybe_assemble_visibility (decl);
1709 }
1710
1711 if (DECL_PRESERVE_P (decl))
1712 targetm.asm_out.mark_decl_preserved (fnname);
1713
1714 /* Do any machine/system dependent processing of the function name. */
1715 #ifdef ASM_DECLARE_FUNCTION_NAME
1716 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1717 #else
1718 /* Standard thing is just output label for the function. */
1719 ASM_OUTPUT_FUNCTION_LABEL (asm_out_file, fnname, current_function_decl);
1720 #endif /* ASM_DECLARE_FUNCTION_NAME */
1721
1722 if (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (decl)))
1723 saw_no_split_stack = true;
1724 }
1725
1726 /* Output assembler code associated with defining the size of the
1727 function. DECL describes the function. NAME is the function's name. */
1728
1729 void
1730 assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED)
1731 {
1732 #ifdef ASM_DECLARE_FUNCTION_SIZE
1733 /* We could have switched section in the middle of the function. */
1734 if (flag_reorder_blocks_and_partition)
1735 switch_to_section (function_section (decl));
1736 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1737 #endif
1738 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1739 {
1740 output_constant_pool (fnname, decl);
1741 switch_to_section (function_section (decl)); /* need to switch back */
1742 }
1743 /* Output labels for end of hot/cold text sections (to be used by
1744 debug info.) */
1745 if (flag_reorder_blocks_and_partition)
1746 {
1747 section *save_text_section;
1748
1749 save_text_section = in_section;
1750 switch_to_section (unlikely_text_section ());
1751 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label);
1752 if (first_function_block_is_cold)
1753 switch_to_section (text_section);
1754 else
1755 switch_to_section (function_section (decl));
1756 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label);
1757 switch_to_section (save_text_section);
1758 }
1759 }
1760 \f
1761 /* Assemble code to leave SIZE bytes of zeros. */
1762
1763 void
1764 assemble_zeros (unsigned HOST_WIDE_INT size)
1765 {
1766 /* Do no output if -fsyntax-only. */
1767 if (flag_syntax_only)
1768 return;
1769
1770 #ifdef ASM_NO_SKIP_IN_TEXT
1771 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1772 so we must output 0s explicitly in the text section. */
1773 if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0)
1774 {
1775 unsigned HOST_WIDE_INT i;
1776 for (i = 0; i < size; i++)
1777 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1778 }
1779 else
1780 #endif
1781 if (size > 0)
1782 ASM_OUTPUT_SKIP (asm_out_file, size);
1783 }
1784
1785 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1786
1787 void
1788 assemble_align (int align)
1789 {
1790 if (align > BITS_PER_UNIT)
1791 {
1792 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1793 }
1794 }
1795
1796 /* Assemble a string constant with the specified C string as contents. */
1797
1798 void
1799 assemble_string (const char *p, int size)
1800 {
1801 int pos = 0;
1802 int maximum = 2000;
1803
1804 /* If the string is very long, split it up. */
1805
1806 while (pos < size)
1807 {
1808 int thissize = size - pos;
1809 if (thissize > maximum)
1810 thissize = maximum;
1811
1812 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1813
1814 pos += thissize;
1815 p += thissize;
1816 }
1817 }
1818
1819 \f
1820 /* A noswitch_section_callback for lcomm_section. */
1821
1822 static bool
1823 emit_local (tree decl ATTRIBUTE_UNUSED,
1824 const char *name ATTRIBUTE_UNUSED,
1825 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1826 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1827 {
1828 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1829 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name,
1830 size, DECL_ALIGN (decl));
1831 return true;
1832 #elif defined ASM_OUTPUT_ALIGNED_LOCAL
1833 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, DECL_ALIGN (decl));
1834 return true;
1835 #else
1836 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1837 return false;
1838 #endif
1839 }
1840
1841 /* A noswitch_section_callback for bss_noswitch_section. */
1842
1843 #if defined ASM_OUTPUT_ALIGNED_BSS
1844 static bool
1845 emit_bss (tree decl ATTRIBUTE_UNUSED,
1846 const char *name ATTRIBUTE_UNUSED,
1847 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1848 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1849 {
1850 #if defined ASM_OUTPUT_ALIGNED_BSS
1851 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size,
1852 get_variable_align (decl));
1853 return true;
1854 #endif
1855 }
1856 #endif
1857
1858 /* A noswitch_section_callback for comm_section. */
1859
1860 static bool
1861 emit_common (tree decl ATTRIBUTE_UNUSED,
1862 const char *name ATTRIBUTE_UNUSED,
1863 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1864 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1865 {
1866 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1867 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name,
1868 size, get_variable_align (decl));
1869 return true;
1870 #elif defined ASM_OUTPUT_ALIGNED_COMMON
1871 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size,
1872 get_variable_align (decl));
1873 return true;
1874 #else
1875 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
1876 return false;
1877 #endif
1878 }
1879
1880 /* A noswitch_section_callback for tls_comm_section. */
1881
1882 static bool
1883 emit_tls_common (tree decl ATTRIBUTE_UNUSED,
1884 const char *name ATTRIBUTE_UNUSED,
1885 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1886 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1887 {
1888 #ifdef ASM_OUTPUT_TLS_COMMON
1889 ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size);
1890 return true;
1891 #else
1892 sorry ("thread-local COMMON data not implemented");
1893 return true;
1894 #endif
1895 }
1896
1897 /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT.
1898 NAME is the name of DECL's SYMBOL_REF. */
1899
1900 static void
1901 assemble_noswitch_variable (tree decl, const char *name, section *sect,
1902 unsigned int align)
1903 {
1904 unsigned HOST_WIDE_INT size, rounded;
1905
1906 size = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
1907 rounded = size;
1908
1909 if ((flag_sanitize & SANITIZE_ADDRESS) && asan_protect_global (decl))
1910 size += asan_red_zone_size (size);
1911
1912 /* Don't allocate zero bytes of common,
1913 since that means "undefined external" in the linker. */
1914 if (size == 0)
1915 rounded = 1;
1916
1917 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1918 so that each uninitialized object starts on such a boundary. */
1919 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
1920 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1921 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1922
1923 if (!sect->noswitch.callback (decl, name, size, rounded)
1924 && (unsigned HOST_WIDE_INT) (align / BITS_PER_UNIT) > rounded)
1925 warning (0, "requested alignment for %q+D is greater than "
1926 "implemented alignment of %wu", decl, rounded);
1927 }
1928
1929 /* A subroutine of assemble_variable. Output the label and contents of
1930 DECL, whose address is a SYMBOL_REF with name NAME. DONT_OUTPUT_DATA
1931 is as for assemble_variable. */
1932
1933 static void
1934 assemble_variable_contents (tree decl, const char *name,
1935 bool dont_output_data)
1936 {
1937 /* Do any machine/system dependent processing of the object. */
1938 #ifdef ASM_DECLARE_OBJECT_NAME
1939 last_assemble_variable_decl = decl;
1940 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
1941 #else
1942 /* Standard thing is just output label for the object. */
1943 ASM_OUTPUT_LABEL (asm_out_file, name);
1944 #endif /* ASM_DECLARE_OBJECT_NAME */
1945
1946 if (!dont_output_data)
1947 {
1948 if (DECL_INITIAL (decl)
1949 && DECL_INITIAL (decl) != error_mark_node
1950 && !initializer_zerop (DECL_INITIAL (decl)))
1951 /* Output the actual data. */
1952 output_constant (DECL_INITIAL (decl),
1953 tree_low_cst (DECL_SIZE_UNIT (decl), 1),
1954 get_variable_align (decl));
1955 else
1956 /* Leave space for it. */
1957 assemble_zeros (tree_low_cst (DECL_SIZE_UNIT (decl), 1));
1958 }
1959 }
1960
1961 /* Assemble everything that is needed for a variable or function declaration.
1962 Not used for automatic variables, and not used for function definitions.
1963 Should not be called for variables of incomplete structure type.
1964
1965 TOP_LEVEL is nonzero if this variable has file scope.
1966 AT_END is nonzero if this is the special handling, at end of compilation,
1967 to define things that have had only tentative definitions.
1968 DONT_OUTPUT_DATA if nonzero means don't actually output the
1969 initial value (that will be done by the caller). */
1970
1971 void
1972 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
1973 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
1974 {
1975 const char *name;
1976 rtx decl_rtl, symbol;
1977 section *sect;
1978 unsigned int align;
1979 bool asan_protected = false;
1980
1981 /* This function is supposed to handle VARIABLES. Ensure we have one. */
1982 gcc_assert (TREE_CODE (decl) == VAR_DECL);
1983
1984 /* Emulated TLS had better not get this far. */
1985 gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl));
1986
1987 last_assemble_variable_decl = 0;
1988
1989 /* Normally no need to say anything here for external references,
1990 since assemble_external is called by the language-specific code
1991 when a declaration is first seen. */
1992
1993 if (DECL_EXTERNAL (decl))
1994 return;
1995
1996 /* Do nothing for global register variables. */
1997 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
1998 {
1999 TREE_ASM_WRITTEN (decl) = 1;
2000 return;
2001 }
2002
2003 /* If type was incomplete when the variable was declared,
2004 see if it is complete now. */
2005
2006 if (DECL_SIZE (decl) == 0)
2007 layout_decl (decl, 0);
2008
2009 /* Still incomplete => don't allocate it; treat the tentative defn
2010 (which is what it must have been) as an `extern' reference. */
2011
2012 if (!dont_output_data && DECL_SIZE (decl) == 0)
2013 {
2014 error ("storage size of %q+D isn%'t known", decl);
2015 TREE_ASM_WRITTEN (decl) = 1;
2016 return;
2017 }
2018
2019 /* The first declaration of a variable that comes through this function
2020 decides whether it is global (in C, has external linkage)
2021 or local (in C, has internal linkage). So do nothing more
2022 if this function has already run. */
2023
2024 if (TREE_ASM_WRITTEN (decl))
2025 return;
2026
2027 /* Make sure targetm.encode_section_info is invoked before we set
2028 ASM_WRITTEN. */
2029 decl_rtl = DECL_RTL (decl);
2030
2031 TREE_ASM_WRITTEN (decl) = 1;
2032
2033 /* Do no output if -fsyntax-only. */
2034 if (flag_syntax_only)
2035 return;
2036
2037 if (! dont_output_data
2038 && ! valid_constant_size_p (DECL_SIZE_UNIT (decl)))
2039 {
2040 error ("size of variable %q+D is too large", decl);
2041 return;
2042 }
2043
2044 gcc_assert (MEM_P (decl_rtl));
2045 gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF);
2046 symbol = XEXP (decl_rtl, 0);
2047
2048 /* If this symbol belongs to the tree constant pool, output the constant
2049 if it hasn't already been written. */
2050 if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
2051 {
2052 tree decl = SYMBOL_REF_DECL (symbol);
2053 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
2054 output_constant_def_contents (symbol);
2055 return;
2056 }
2057
2058 app_disable ();
2059
2060 name = XSTR (symbol, 0);
2061 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
2062 notice_global_symbol (decl);
2063
2064 /* Compute the alignment of this data. */
2065
2066 align_variable (decl, dont_output_data);
2067
2068 if ((flag_sanitize & SANITIZE_ADDRESS)
2069 && asan_protect_global (decl))
2070 {
2071 asan_protected = true;
2072 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
2073 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
2074 }
2075
2076 set_mem_align (decl_rtl, DECL_ALIGN (decl));
2077
2078 align = get_variable_align (decl);
2079
2080 if (TREE_PUBLIC (decl))
2081 maybe_assemble_visibility (decl);
2082
2083 if (DECL_PRESERVE_P (decl))
2084 targetm.asm_out.mark_decl_preserved (name);
2085
2086 /* First make the assembler name(s) global if appropriate. */
2087 sect = get_variable_section (decl, false);
2088 if (TREE_PUBLIC (decl)
2089 && (sect->common.flags & SECTION_COMMON) == 0)
2090 globalize_decl (decl);
2091
2092 /* Output any data that we will need to use the address of. */
2093 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
2094 output_addressed_constants (DECL_INITIAL (decl));
2095
2096 /* dbxout.c needs to know this. */
2097 if (sect && (sect->common.flags & SECTION_CODE) != 0)
2098 DECL_IN_TEXT_SECTION (decl) = 1;
2099
2100 /* If the decl is part of an object_block, make sure that the decl
2101 has been positioned within its block, but do not write out its
2102 definition yet. output_object_blocks will do that later. */
2103 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
2104 {
2105 gcc_assert (!dont_output_data);
2106 place_block_symbol (symbol);
2107 }
2108 else if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
2109 assemble_noswitch_variable (decl, name, sect, align);
2110 else
2111 {
2112 /* The following bit of code ensures that vtable_map
2113 variables are not only in the comdat section, but that
2114 each variable has its own unique comdat name. If this
2115 code is removed, the variables end up in the same section
2116 with a single comdat name.
2117
2118 FIXME: resolve_unique_section needs to deal better with
2119 decls with both DECL_SECTION_NAME and DECL_ONE_ONLY. Once
2120 that is fixed, this if-else statement can be replaced with
2121 a single call to "switch_to_section (sect)". */
2122 if (sect->named.name
2123 && (strcmp (sect->named.name, ".vtable_map_vars") == 0))
2124 {
2125 #if defined (OBJECT_FORMAT_ELF)
2126 targetm.asm_out.named_section (sect->named.name,
2127 sect->named.common.flags
2128 | SECTION_LINKONCE,
2129 DECL_NAME (decl));
2130 in_section = sect;
2131 #else
2132 switch_to_section (sect);
2133 #endif
2134 }
2135 else
2136 switch_to_section (sect);
2137 if (align > BITS_PER_UNIT)
2138 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2139 assemble_variable_contents (decl, name, dont_output_data);
2140 if (asan_protected)
2141 {
2142 unsigned HOST_WIDE_INT int size
2143 = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
2144 assemble_zeros (asan_red_zone_size (size));
2145 }
2146 }
2147 }
2148
2149
2150 /* Given a function declaration (FN_DECL), this function assembles the
2151 function into the .preinit_array section. */
2152
2153 void
2154 assemble_vtv_preinit_initializer (tree fn_decl)
2155 {
2156 section *sect;
2157 unsigned flags = SECTION_WRITE;
2158 rtx symbol = XEXP (DECL_RTL (fn_decl), 0);
2159
2160 flags |= SECTION_NOTYPE;
2161 sect = get_section (".preinit_array", flags, fn_decl);
2162 switch_to_section (sect);
2163 assemble_addr_to_section (symbol, sect);
2164 }
2165
2166 /* Return 1 if type TYPE contains any pointers. */
2167
2168 static int
2169 contains_pointers_p (tree type)
2170 {
2171 switch (TREE_CODE (type))
2172 {
2173 case POINTER_TYPE:
2174 case REFERENCE_TYPE:
2175 /* I'm not sure whether OFFSET_TYPE needs this treatment,
2176 so I'll play safe and return 1. */
2177 case OFFSET_TYPE:
2178 return 1;
2179
2180 case RECORD_TYPE:
2181 case UNION_TYPE:
2182 case QUAL_UNION_TYPE:
2183 {
2184 tree fields;
2185 /* For a type that has fields, see if the fields have pointers. */
2186 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2187 if (TREE_CODE (fields) == FIELD_DECL
2188 && contains_pointers_p (TREE_TYPE (fields)))
2189 return 1;
2190 return 0;
2191 }
2192
2193 case ARRAY_TYPE:
2194 /* An array type contains pointers if its element type does. */
2195 return contains_pointers_p (TREE_TYPE (type));
2196
2197 default:
2198 return 0;
2199 }
2200 }
2201
2202 /* We delay assemble_external processing until
2203 the compilation unit is finalized. This is the best we can do for
2204 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2205 it all the way to final. See PR 17982 for further discussion. */
2206 static GTY(()) tree pending_assemble_externals;
2207
2208 #ifdef ASM_OUTPUT_EXTERNAL
2209 /* Some targets delay some output to final using TARGET_ASM_FILE_END.
2210 As a result, assemble_external can be called after the list of externals
2211 is processed and the pointer set destroyed. */
2212 static bool pending_assemble_externals_processed;
2213
2214 /* Avoid O(external_decls**2) lookups in the pending_assemble_externals
2215 TREE_LIST in assemble_external. */
2216 static struct pointer_set_t *pending_assemble_externals_set;
2217
2218 /* True if DECL is a function decl for which no out-of-line copy exists.
2219 It is assumed that DECL's assembler name has been set. */
2220
2221 static bool
2222 incorporeal_function_p (tree decl)
2223 {
2224 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
2225 {
2226 const char *name;
2227
2228 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2229 && (DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA
2230 || DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA_WITH_ALIGN))
2231 return true;
2232
2233 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2234 /* Atomic or sync builtins which have survived this far will be
2235 resolved externally and therefore are not incorporeal. */
2236 if (strncmp (name, "__builtin_", 10) == 0)
2237 return true;
2238 }
2239 return false;
2240 }
2241
2242 /* Actually do the tests to determine if this is necessary, and invoke
2243 ASM_OUTPUT_EXTERNAL. */
2244 static void
2245 assemble_external_real (tree decl)
2246 {
2247 rtx rtl = DECL_RTL (decl);
2248
2249 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2250 && !SYMBOL_REF_USED (XEXP (rtl, 0))
2251 && !incorporeal_function_p (decl))
2252 {
2253 /* Some systems do require some output. */
2254 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2255 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2256 }
2257 }
2258 #endif
2259
2260 void
2261 process_pending_assemble_externals (void)
2262 {
2263 #ifdef ASM_OUTPUT_EXTERNAL
2264 tree list;
2265 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2266 assemble_external_real (TREE_VALUE (list));
2267
2268 pending_assemble_externals = 0;
2269 pending_assemble_externals_processed = true;
2270 pointer_set_destroy (pending_assemble_externals_set);
2271 #endif
2272 }
2273
2274 /* This TREE_LIST contains any weak symbol declarations waiting
2275 to be emitted. */
2276 static GTY(()) tree weak_decls;
2277
2278 /* Output something to declare an external symbol to the assembler,
2279 and qualifiers such as weakness. (Most assemblers don't need
2280 extern declaration, so we normally output nothing.) Do nothing if
2281 DECL is not external. */
2282
2283 void
2284 assemble_external (tree decl ATTRIBUTE_UNUSED)
2285 {
2286 /* Make sure that the ASM_OUT_FILE is open.
2287 If it's not, we should not be calling this function. */
2288 gcc_assert (asm_out_file);
2289
2290 /* In a perfect world, the following condition would be true.
2291 Sadly, the Java and Go front ends emit assembly *from the front end*,
2292 bypassing the call graph. See PR52739. Fix before GCC 4.8. */
2293 #if 0
2294 /* This function should only be called if we are expanding, or have
2295 expanded, to RTL.
2296 Ideally, only final.c would be calling this function, but it is
2297 not clear whether that would break things somehow. See PR 17982
2298 for further discussion. */
2299 gcc_assert (cgraph_state == CGRAPH_STATE_EXPANSION
2300 || cgraph_state == CGRAPH_STATE_FINISHED);
2301 #endif
2302
2303 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2304 return;
2305
2306 /* We want to output annotation for weak and external symbols at
2307 very last to check if they are references or not. */
2308
2309 if (TARGET_SUPPORTS_WEAK
2310 && DECL_WEAK (decl)
2311 /* TREE_STATIC is a weird and abused creature which is not
2312 generally the right test for whether an entity has been
2313 locally emitted, inlined or otherwise not-really-extern, but
2314 for declarations that can be weak, it happens to be
2315 match. */
2316 && !TREE_STATIC (decl)
2317 && lookup_attribute ("weak", DECL_ATTRIBUTES (decl))
2318 && value_member (decl, weak_decls) == NULL_TREE)
2319 weak_decls = tree_cons (NULL, decl, weak_decls);
2320
2321 #ifdef ASM_OUTPUT_EXTERNAL
2322 if (pending_assemble_externals_processed)
2323 {
2324 assemble_external_real (decl);
2325 return;
2326 }
2327
2328 if (! pointer_set_insert (pending_assemble_externals_set, decl))
2329 pending_assemble_externals = tree_cons (NULL, decl,
2330 pending_assemble_externals);
2331 #endif
2332 }
2333
2334 /* Similar, for calling a library function FUN. */
2335
2336 void
2337 assemble_external_libcall (rtx fun)
2338 {
2339 /* Declare library function name external when first used, if nec. */
2340 if (! SYMBOL_REF_USED (fun))
2341 {
2342 SYMBOL_REF_USED (fun) = 1;
2343 targetm.asm_out.external_libcall (fun);
2344 }
2345 }
2346
2347 /* Assemble a label named NAME. */
2348
2349 void
2350 assemble_label (FILE *file, const char *name)
2351 {
2352 ASM_OUTPUT_LABEL (file, name);
2353 }
2354
2355 /* Set the symbol_referenced flag for ID. */
2356 void
2357 mark_referenced (tree id)
2358 {
2359 TREE_SYMBOL_REFERENCED (id) = 1;
2360 }
2361
2362 /* Set the symbol_referenced flag for DECL and notify callgraph. */
2363 void
2364 mark_decl_referenced (tree decl)
2365 {
2366 if (TREE_CODE (decl) == FUNCTION_DECL)
2367 {
2368 /* Extern inline functions don't become needed when referenced.
2369 If we know a method will be emitted in other TU and no new
2370 functions can be marked reachable, just use the external
2371 definition. */
2372 struct cgraph_node *node = cgraph_get_create_node (decl);
2373 if (!DECL_EXTERNAL (decl)
2374 && !node->symbol.definition)
2375 cgraph_mark_force_output_node (node);
2376 }
2377 else if (TREE_CODE (decl) == VAR_DECL)
2378 {
2379 struct varpool_node *node = varpool_node_for_decl (decl);
2380 /* C++ frontend use mark_decl_references to force COMDAT variables
2381 to be output that might appear dead otherwise. */
2382 node->symbol.force_output = true;
2383 }
2384 /* else do nothing - we can get various sorts of CST nodes here,
2385 which do not need to be marked. */
2386 }
2387
2388
2389 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS
2390 until we find an identifier that is not itself a transparent alias.
2391 Modify the alias passed to it by reference (and all aliases on the
2392 way to the ultimate target), such that they do not have to be
2393 followed again, and return the ultimate target of the alias
2394 chain. */
2395
2396 static inline tree
2397 ultimate_transparent_alias_target (tree *alias)
2398 {
2399 tree target = *alias;
2400
2401 if (IDENTIFIER_TRANSPARENT_ALIAS (target))
2402 {
2403 gcc_assert (TREE_CHAIN (target));
2404 target = ultimate_transparent_alias_target (&TREE_CHAIN (target));
2405 gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target)
2406 && ! TREE_CHAIN (target));
2407 *alias = target;
2408 }
2409
2410 return target;
2411 }
2412
2413 /* Output to FILE (an assembly file) a reference to NAME. If NAME
2414 starts with a *, the rest of NAME is output verbatim. Otherwise
2415 NAME is transformed in a target-specific way (usually by the
2416 addition of an underscore). */
2417
2418 void
2419 assemble_name_raw (FILE *file, const char *name)
2420 {
2421 if (name[0] == '*')
2422 fputs (&name[1], file);
2423 else
2424 ASM_OUTPUT_LABELREF (file, name);
2425 }
2426
2427 /* Like assemble_name_raw, but should be used when NAME might refer to
2428 an entity that is also represented as a tree (like a function or
2429 variable). If NAME does refer to such an entity, that entity will
2430 be marked as referenced. */
2431
2432 void
2433 assemble_name (FILE *file, const char *name)
2434 {
2435 const char *real_name;
2436 tree id;
2437
2438 real_name = targetm.strip_name_encoding (name);
2439
2440 id = maybe_get_identifier (real_name);
2441 if (id)
2442 {
2443 tree id_orig = id;
2444
2445 mark_referenced (id);
2446 ultimate_transparent_alias_target (&id);
2447 if (id != id_orig)
2448 name = IDENTIFIER_POINTER (id);
2449 gcc_assert (! TREE_CHAIN (id));
2450 }
2451
2452 assemble_name_raw (file, name);
2453 }
2454
2455 /* Allocate SIZE bytes writable static space with a gensym name
2456 and return an RTX to refer to its address. */
2457
2458 rtx
2459 assemble_static_space (unsigned HOST_WIDE_INT size)
2460 {
2461 char name[12];
2462 const char *namestring;
2463 rtx x;
2464
2465 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2466 ++const_labelno;
2467 namestring = ggc_strdup (name);
2468
2469 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2470 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2471
2472 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2473 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2474 BIGGEST_ALIGNMENT);
2475 #else
2476 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2477 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2478 #else
2479 {
2480 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2481 so that each uninitialized object starts on such a boundary. */
2482 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2483 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2484 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2485 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2486 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2487 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2488 }
2489 #endif
2490 #endif
2491 return x;
2492 }
2493
2494 /* Assemble the static constant template for function entry trampolines.
2495 This is done at most once per compilation.
2496 Returns an RTX for the address of the template. */
2497
2498 static GTY(()) rtx initial_trampoline;
2499
2500 rtx
2501 assemble_trampoline_template (void)
2502 {
2503 char label[256];
2504 const char *name;
2505 int align;
2506 rtx symbol;
2507
2508 gcc_assert (targetm.asm_out.trampoline_template != NULL);
2509
2510 if (initial_trampoline)
2511 return initial_trampoline;
2512
2513 /* By default, put trampoline templates in read-only data section. */
2514
2515 #ifdef TRAMPOLINE_SECTION
2516 switch_to_section (TRAMPOLINE_SECTION);
2517 #else
2518 switch_to_section (readonly_data_section);
2519 #endif
2520
2521 /* Write the assembler code to define one. */
2522 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2523 if (align > 0)
2524 ASM_OUTPUT_ALIGN (asm_out_file, align);
2525
2526 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2527 targetm.asm_out.trampoline_template (asm_out_file);
2528
2529 /* Record the rtl to refer to it. */
2530 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2531 name = ggc_strdup (label);
2532 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2533 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2534
2535 initial_trampoline = gen_const_mem (BLKmode, symbol);
2536 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2537 set_mem_size (initial_trampoline, TRAMPOLINE_SIZE);
2538
2539 return initial_trampoline;
2540 }
2541 \f
2542 /* A and B are either alignments or offsets. Return the minimum alignment
2543 that may be assumed after adding the two together. */
2544
2545 static inline unsigned
2546 min_align (unsigned int a, unsigned int b)
2547 {
2548 return (a | b) & -(a | b);
2549 }
2550
2551 /* Return the assembler directive for creating a given kind of integer
2552 object. SIZE is the number of bytes in the object and ALIGNED_P
2553 indicates whether it is known to be aligned. Return NULL if the
2554 assembly dialect has no such directive.
2555
2556 The returned string should be printed at the start of a new line and
2557 be followed immediately by the object's initial value. */
2558
2559 const char *
2560 integer_asm_op (int size, int aligned_p)
2561 {
2562 struct asm_int_op *ops;
2563
2564 if (aligned_p)
2565 ops = &targetm.asm_out.aligned_op;
2566 else
2567 ops = &targetm.asm_out.unaligned_op;
2568
2569 switch (size)
2570 {
2571 case 1:
2572 return targetm.asm_out.byte_op;
2573 case 2:
2574 return ops->hi;
2575 case 4:
2576 return ops->si;
2577 case 8:
2578 return ops->di;
2579 case 16:
2580 return ops->ti;
2581 default:
2582 return NULL;
2583 }
2584 }
2585
2586 /* Use directive OP to assemble an integer object X. Print OP at the
2587 start of the line, followed immediately by the value of X. */
2588
2589 void
2590 assemble_integer_with_op (const char *op, rtx x)
2591 {
2592 fputs (op, asm_out_file);
2593 output_addr_const (asm_out_file, x);
2594 fputc ('\n', asm_out_file);
2595 }
2596
2597 /* The default implementation of the asm_out.integer target hook. */
2598
2599 bool
2600 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2601 unsigned int size ATTRIBUTE_UNUSED,
2602 int aligned_p ATTRIBUTE_UNUSED)
2603 {
2604 const char *op = integer_asm_op (size, aligned_p);
2605 /* Avoid GAS bugs for large values. Specifically negative values whose
2606 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2607 if (size > UNITS_PER_WORD && size > POINTER_SIZE / BITS_PER_UNIT)
2608 return false;
2609 return op && (assemble_integer_with_op (op, x), true);
2610 }
2611
2612 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2613 the alignment of the integer in bits. Return 1 if we were able to output
2614 the constant, otherwise 0. We must be able to output the constant,
2615 if FORCE is nonzero. */
2616
2617 bool
2618 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2619 {
2620 int aligned_p;
2621
2622 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2623
2624 /* See if the target hook can handle this kind of object. */
2625 if (targetm.asm_out.integer (x, size, aligned_p))
2626 return true;
2627
2628 /* If the object is a multi-byte one, try splitting it up. Split
2629 it into words it if is multi-word, otherwise split it into bytes. */
2630 if (size > 1)
2631 {
2632 enum machine_mode omode, imode;
2633 unsigned int subalign;
2634 unsigned int subsize, i;
2635 enum mode_class mclass;
2636
2637 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2638 subalign = MIN (align, subsize * BITS_PER_UNIT);
2639 if (GET_CODE (x) == CONST_FIXED)
2640 mclass = GET_MODE_CLASS (GET_MODE (x));
2641 else
2642 mclass = MODE_INT;
2643
2644 omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0);
2645 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0);
2646
2647 for (i = 0; i < size; i += subsize)
2648 {
2649 rtx partial = simplify_subreg (omode, x, imode, i);
2650 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2651 break;
2652 }
2653 if (i == size)
2654 return true;
2655
2656 /* If we've printed some of it, but not all of it, there's no going
2657 back now. */
2658 gcc_assert (!i);
2659 }
2660
2661 gcc_assert (!force);
2662
2663 return false;
2664 }
2665 \f
2666 void
2667 assemble_real (REAL_VALUE_TYPE d, enum machine_mode mode, unsigned int align)
2668 {
2669 long data[4] = {0, 0, 0, 0};
2670 int i;
2671 int bitsize, nelts, nunits, units_per;
2672
2673 /* This is hairy. We have a quantity of known size. real_to_target
2674 will put it into an array of *host* longs, 32 bits per element
2675 (even if long is more than 32 bits). We need to determine the
2676 number of array elements that are occupied (nelts) and the number
2677 of *target* min-addressable units that will be occupied in the
2678 object file (nunits). We cannot assume that 32 divides the
2679 mode's bitsize (size * BITS_PER_UNIT) evenly.
2680
2681 size * BITS_PER_UNIT is used here to make sure that padding bits
2682 (which might appear at either end of the value; real_to_target
2683 will include the padding bits in its output array) are included. */
2684
2685 nunits = GET_MODE_SIZE (mode);
2686 bitsize = nunits * BITS_PER_UNIT;
2687 nelts = CEIL (bitsize, 32);
2688 units_per = 32 / BITS_PER_UNIT;
2689
2690 real_to_target (data, &d, mode);
2691
2692 /* Put out the first word with the specified alignment. */
2693 assemble_integer (GEN_INT (data[0]), MIN (nunits, units_per), align, 1);
2694 nunits -= units_per;
2695
2696 /* Subsequent words need only 32-bit alignment. */
2697 align = min_align (align, 32);
2698
2699 for (i = 1; i < nelts; i++)
2700 {
2701 assemble_integer (GEN_INT (data[i]), MIN (nunits, units_per), align, 1);
2702 nunits -= units_per;
2703 }
2704 }
2705 \f
2706 /* Given an expression EXP with a constant value,
2707 reduce it to the sum of an assembler symbol and an integer.
2708 Store them both in the structure *VALUE.
2709 EXP must be reducible. */
2710
2711 struct addr_const {
2712 rtx base;
2713 HOST_WIDE_INT offset;
2714 };
2715
2716 static void
2717 decode_addr_const (tree exp, struct addr_const *value)
2718 {
2719 tree target = TREE_OPERAND (exp, 0);
2720 int offset = 0;
2721 rtx x;
2722
2723 while (1)
2724 {
2725 if (TREE_CODE (target) == COMPONENT_REF
2726 && host_integerp (byte_position (TREE_OPERAND (target, 1)), 0))
2727 {
2728 offset += int_byte_position (TREE_OPERAND (target, 1));
2729 target = TREE_OPERAND (target, 0);
2730 }
2731 else if (TREE_CODE (target) == ARRAY_REF
2732 || TREE_CODE (target) == ARRAY_RANGE_REF)
2733 {
2734 offset += (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (target)), 1)
2735 * tree_low_cst (TREE_OPERAND (target, 1), 0));
2736 target = TREE_OPERAND (target, 0);
2737 }
2738 else if (TREE_CODE (target) == MEM_REF
2739 && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR)
2740 {
2741 offset += mem_ref_offset (target).low;
2742 target = TREE_OPERAND (TREE_OPERAND (target, 0), 0);
2743 }
2744 else if (TREE_CODE (target) == INDIRECT_REF
2745 && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR
2746 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0))
2747 == ADDR_EXPR)
2748 target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0);
2749 else
2750 break;
2751 }
2752
2753 switch (TREE_CODE (target))
2754 {
2755 case VAR_DECL:
2756 case FUNCTION_DECL:
2757 x = DECL_RTL (target);
2758 break;
2759
2760 case LABEL_DECL:
2761 x = gen_rtx_MEM (FUNCTION_MODE,
2762 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2763 break;
2764
2765 case REAL_CST:
2766 case FIXED_CST:
2767 case STRING_CST:
2768 case COMPLEX_CST:
2769 case CONSTRUCTOR:
2770 case INTEGER_CST:
2771 x = output_constant_def (target, 1);
2772 break;
2773
2774 default:
2775 gcc_unreachable ();
2776 }
2777
2778 gcc_assert (MEM_P (x));
2779 x = XEXP (x, 0);
2780
2781 value->base = x;
2782 value->offset = offset;
2783 }
2784 \f
2785
2786 static GTY((param_is (struct constant_descriptor_tree)))
2787 htab_t const_desc_htab;
2788
2789 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2790
2791 /* Constant pool accessor function. */
2792
2793 htab_t
2794 constant_pool_htab (void)
2795 {
2796 return const_desc_htab;
2797 }
2798
2799 /* Compute a hash code for a constant expression. */
2800
2801 static hashval_t
2802 const_desc_hash (const void *ptr)
2803 {
2804 return ((const struct constant_descriptor_tree *)ptr)->hash;
2805 }
2806
2807 static hashval_t
2808 const_hash_1 (const tree exp)
2809 {
2810 const char *p;
2811 hashval_t hi;
2812 int len, i;
2813 enum tree_code code = TREE_CODE (exp);
2814
2815 /* Either set P and LEN to the address and len of something to hash and
2816 exit the switch or return a value. */
2817
2818 switch (code)
2819 {
2820 case INTEGER_CST:
2821 p = (char *) &TREE_INT_CST (exp);
2822 len = sizeof TREE_INT_CST (exp);
2823 break;
2824
2825 case REAL_CST:
2826 return real_hash (TREE_REAL_CST_PTR (exp));
2827
2828 case FIXED_CST:
2829 return fixed_hash (TREE_FIXED_CST_PTR (exp));
2830
2831 case STRING_CST:
2832 p = TREE_STRING_POINTER (exp);
2833 len = TREE_STRING_LENGTH (exp);
2834 break;
2835
2836 case COMPLEX_CST:
2837 return (const_hash_1 (TREE_REALPART (exp)) * 5
2838 + const_hash_1 (TREE_IMAGPART (exp)));
2839
2840 case VECTOR_CST:
2841 {
2842 unsigned i;
2843
2844 hi = 7 + VECTOR_CST_NELTS (exp);
2845
2846 for (i = 0; i < VECTOR_CST_NELTS (exp); ++i)
2847 hi = hi * 563 + const_hash_1 (VECTOR_CST_ELT (exp, i));
2848
2849 return hi;
2850 }
2851
2852 case CONSTRUCTOR:
2853 {
2854 unsigned HOST_WIDE_INT idx;
2855 tree value;
2856
2857 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2858
2859 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
2860 if (value)
2861 hi = hi * 603 + const_hash_1 (value);
2862
2863 return hi;
2864 }
2865
2866 case ADDR_EXPR:
2867 case FDESC_EXPR:
2868 {
2869 struct addr_const value;
2870
2871 decode_addr_const (exp, &value);
2872 switch (GET_CODE (value.base))
2873 {
2874 case SYMBOL_REF:
2875 /* Don't hash the address of the SYMBOL_REF;
2876 only use the offset and the symbol name. */
2877 hi = value.offset;
2878 p = XSTR (value.base, 0);
2879 for (i = 0; p[i] != 0; i++)
2880 hi = ((hi * 613) + (unsigned) (p[i]));
2881 break;
2882
2883 case LABEL_REF:
2884 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13;
2885 break;
2886
2887 default:
2888 gcc_unreachable ();
2889 }
2890 }
2891 return hi;
2892
2893 case PLUS_EXPR:
2894 case POINTER_PLUS_EXPR:
2895 case MINUS_EXPR:
2896 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2897 + const_hash_1 (TREE_OPERAND (exp, 1)));
2898
2899 CASE_CONVERT:
2900 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
2901
2902 default:
2903 /* A language specific constant. Just hash the code. */
2904 return code;
2905 }
2906
2907 /* Compute hashing function. */
2908 hi = len;
2909 for (i = 0; i < len; i++)
2910 hi = ((hi * 613) + (unsigned) (p[i]));
2911
2912 return hi;
2913 }
2914
2915 /* Wrapper of compare_constant, for the htab interface. */
2916 static int
2917 const_desc_eq (const void *p1, const void *p2)
2918 {
2919 const struct constant_descriptor_tree *const c1
2920 = (const struct constant_descriptor_tree *) p1;
2921 const struct constant_descriptor_tree *const c2
2922 = (const struct constant_descriptor_tree *) p2;
2923 if (c1->hash != c2->hash)
2924 return 0;
2925 return compare_constant (c1->value, c2->value);
2926 }
2927
2928 /* Compare t1 and t2, and return 1 only if they are known to result in
2929 the same bit pattern on output. */
2930
2931 static int
2932 compare_constant (const tree t1, const tree t2)
2933 {
2934 enum tree_code typecode;
2935
2936 if (t1 == NULL_TREE)
2937 return t2 == NULL_TREE;
2938 if (t2 == NULL_TREE)
2939 return 0;
2940
2941 if (TREE_CODE (t1) != TREE_CODE (t2))
2942 return 0;
2943
2944 switch (TREE_CODE (t1))
2945 {
2946 case INTEGER_CST:
2947 /* Integer constants are the same only if the same width of type. */
2948 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2949 return 0;
2950 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2951 return 0;
2952 return tree_int_cst_equal (t1, t2);
2953
2954 case REAL_CST:
2955 /* Real constants are the same only if the same width of type. */
2956 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2957 return 0;
2958
2959 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
2960
2961 case FIXED_CST:
2962 /* Fixed constants are the same only if the same width of type. */
2963 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2964 return 0;
2965
2966 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
2967
2968 case STRING_CST:
2969 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2970 return 0;
2971
2972 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
2973 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
2974 TREE_STRING_LENGTH (t1)));
2975
2976 case COMPLEX_CST:
2977 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
2978 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
2979
2980 case VECTOR_CST:
2981 {
2982 unsigned i;
2983
2984 if (VECTOR_CST_NELTS (t1) != VECTOR_CST_NELTS (t2))
2985 return 0;
2986
2987 for (i = 0; i < VECTOR_CST_NELTS (t1); ++i)
2988 if (!compare_constant (VECTOR_CST_ELT (t1, i),
2989 VECTOR_CST_ELT (t2, i)))
2990 return 0;
2991
2992 return 1;
2993 }
2994
2995 case CONSTRUCTOR:
2996 {
2997 vec<constructor_elt, va_gc> *v1, *v2;
2998 unsigned HOST_WIDE_INT idx;
2999
3000 typecode = TREE_CODE (TREE_TYPE (t1));
3001 if (typecode != TREE_CODE (TREE_TYPE (t2)))
3002 return 0;
3003
3004 if (typecode == ARRAY_TYPE)
3005 {
3006 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
3007 /* For arrays, check that the sizes all match. */
3008 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
3009 || size_1 == -1
3010 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
3011 return 0;
3012 }
3013 else
3014 {
3015 /* For record and union constructors, require exact type
3016 equality. */
3017 if (TREE_TYPE (t1) != TREE_TYPE (t2))
3018 return 0;
3019 }
3020
3021 v1 = CONSTRUCTOR_ELTS (t1);
3022 v2 = CONSTRUCTOR_ELTS (t2);
3023 if (vec_safe_length (v1) != vec_safe_length (v2))
3024 return 0;
3025
3026 for (idx = 0; idx < vec_safe_length (v1); ++idx)
3027 {
3028 constructor_elt *c1 = &(*v1)[idx];
3029 constructor_elt *c2 = &(*v2)[idx];
3030
3031 /* Check that each value is the same... */
3032 if (!compare_constant (c1->value, c2->value))
3033 return 0;
3034 /* ... and that they apply to the same fields! */
3035 if (typecode == ARRAY_TYPE)
3036 {
3037 if (!compare_constant (c1->index, c2->index))
3038 return 0;
3039 }
3040 else
3041 {
3042 if (c1->index != c2->index)
3043 return 0;
3044 }
3045 }
3046
3047 return 1;
3048 }
3049
3050 case ADDR_EXPR:
3051 case FDESC_EXPR:
3052 {
3053 struct addr_const value1, value2;
3054 enum rtx_code code;
3055 int ret;
3056
3057 decode_addr_const (t1, &value1);
3058 decode_addr_const (t2, &value2);
3059
3060 if (value1.offset != value2.offset)
3061 return 0;
3062
3063 code = GET_CODE (value1.base);
3064 if (code != GET_CODE (value2.base))
3065 return 0;
3066
3067 switch (code)
3068 {
3069 case SYMBOL_REF:
3070 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3071 break;
3072
3073 case LABEL_REF:
3074 ret = (CODE_LABEL_NUMBER (XEXP (value1.base, 0))
3075 == CODE_LABEL_NUMBER (XEXP (value2.base, 0)));
3076 break;
3077
3078 default:
3079 gcc_unreachable ();
3080 }
3081 return ret;
3082 }
3083
3084 case PLUS_EXPR:
3085 case POINTER_PLUS_EXPR:
3086 case MINUS_EXPR:
3087 case RANGE_EXPR:
3088 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3089 && compare_constant (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3090
3091 CASE_CONVERT:
3092 case VIEW_CONVERT_EXPR:
3093 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3094
3095 default:
3096 return 0;
3097 }
3098
3099 gcc_unreachable ();
3100 }
3101 \f
3102 /* Make a copy of the whole tree structure for a constant. This
3103 handles the same types of nodes that compare_constant handles. */
3104
3105 static tree
3106 copy_constant (tree exp)
3107 {
3108 switch (TREE_CODE (exp))
3109 {
3110 case ADDR_EXPR:
3111 /* For ADDR_EXPR, we do not want to copy the decl whose address
3112 is requested. We do want to copy constants though. */
3113 if (CONSTANT_CLASS_P (TREE_OPERAND (exp, 0)))
3114 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
3115 copy_constant (TREE_OPERAND (exp, 0)));
3116 else
3117 return copy_node (exp);
3118
3119 case INTEGER_CST:
3120 case REAL_CST:
3121 case FIXED_CST:
3122 case STRING_CST:
3123 return copy_node (exp);
3124
3125 case COMPLEX_CST:
3126 return build_complex (TREE_TYPE (exp),
3127 copy_constant (TREE_REALPART (exp)),
3128 copy_constant (TREE_IMAGPART (exp)));
3129
3130 case PLUS_EXPR:
3131 case POINTER_PLUS_EXPR:
3132 case MINUS_EXPR:
3133 return build2 (TREE_CODE (exp), TREE_TYPE (exp),
3134 copy_constant (TREE_OPERAND (exp, 0)),
3135 copy_constant (TREE_OPERAND (exp, 1)));
3136
3137 CASE_CONVERT:
3138 case VIEW_CONVERT_EXPR:
3139 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
3140 copy_constant (TREE_OPERAND (exp, 0)));
3141
3142 case VECTOR_CST:
3143 return build_vector (TREE_TYPE (exp), VECTOR_CST_ELTS (exp));
3144
3145 case CONSTRUCTOR:
3146 {
3147 tree copy = copy_node (exp);
3148 vec<constructor_elt, va_gc> *v;
3149 unsigned HOST_WIDE_INT idx;
3150 tree purpose, value;
3151
3152 vec_alloc (v, vec_safe_length (CONSTRUCTOR_ELTS (exp)));
3153 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (exp), idx, purpose, value)
3154 {
3155 constructor_elt ce = {purpose, copy_constant (value)};
3156 v->quick_push (ce);
3157 }
3158 CONSTRUCTOR_ELTS (copy) = v;
3159 return copy;
3160 }
3161
3162 default:
3163 gcc_unreachable ();
3164 }
3165 }
3166 \f
3167 /* Return the section into which constant EXP should be placed. */
3168
3169 static section *
3170 get_constant_section (tree exp, unsigned int align)
3171 {
3172 return targetm.asm_out.select_section (exp,
3173 compute_reloc_for_constant (exp),
3174 align);
3175 }
3176
3177 /* Return the size of constant EXP in bytes. */
3178
3179 static HOST_WIDE_INT
3180 get_constant_size (tree exp)
3181 {
3182 HOST_WIDE_INT size;
3183
3184 size = int_size_in_bytes (TREE_TYPE (exp));
3185 if (TREE_CODE (exp) == STRING_CST)
3186 size = MAX (TREE_STRING_LENGTH (exp), size);
3187 return size;
3188 }
3189
3190 /* Subroutine of output_constant_def:
3191 No constant equal to EXP is known to have been output.
3192 Make a constant descriptor to enter EXP in the hash table.
3193 Assign the label number and construct RTL to refer to the
3194 constant's location in memory.
3195 Caller is responsible for updating the hash table. */
3196
3197 static struct constant_descriptor_tree *
3198 build_constant_desc (tree exp)
3199 {
3200 struct constant_descriptor_tree *desc;
3201 rtx symbol, rtl;
3202 char label[256];
3203 int labelno;
3204 tree decl;
3205
3206 desc = ggc_alloc_constant_descriptor_tree ();
3207 desc->value = copy_constant (exp);
3208
3209 /* Propagate marked-ness to copied constant. */
3210 if (flag_mudflap && mf_marked_p (exp))
3211 mf_mark (desc->value);
3212
3213 /* Create a string containing the label name, in LABEL. */
3214 labelno = const_labelno++;
3215 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3216
3217 /* Construct the VAR_DECL associated with the constant. */
3218 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3219 TREE_TYPE (exp));
3220 DECL_ARTIFICIAL (decl) = 1;
3221 DECL_IGNORED_P (decl) = 1;
3222 TREE_READONLY (decl) = 1;
3223 TREE_STATIC (decl) = 1;
3224 TREE_ADDRESSABLE (decl) = 1;
3225 /* We don't set the RTL yet as this would cause varpool to assume that the
3226 variable is referenced. Moreover, it would just be dropped in LTO mode.
3227 Instead we set the flag that will be recognized in make_decl_rtl. */
3228 DECL_IN_CONSTANT_POOL (decl) = 1;
3229 DECL_INITIAL (decl) = desc->value;
3230 /* ??? CONSTANT_ALIGNMENT hasn't been updated for vector types on most
3231 architectures so use DATA_ALIGNMENT as well, except for strings. */
3232 if (TREE_CODE (exp) == STRING_CST)
3233 {
3234 #ifdef CONSTANT_ALIGNMENT
3235 DECL_ALIGN (decl) = CONSTANT_ALIGNMENT (exp, DECL_ALIGN (decl));
3236 #endif
3237 }
3238 else
3239 align_variable (decl, 0);
3240
3241 /* Now construct the SYMBOL_REF and the MEM. */
3242 if (use_object_blocks_p ())
3243 {
3244 section *sect = get_constant_section (exp, DECL_ALIGN (decl));
3245 symbol = create_block_symbol (ggc_strdup (label),
3246 get_block_for_section (sect), -1);
3247 }
3248 else
3249 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3250 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3251 SET_SYMBOL_REF_DECL (symbol, decl);
3252 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3253
3254 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3255 set_mem_attributes (rtl, exp, 1);
3256 set_mem_alias_set (rtl, 0);
3257 set_mem_alias_set (rtl, const_alias_set);
3258
3259 /* We cannot share RTX'es in pool entries.
3260 Mark this piece of RTL as required for unsharing. */
3261 RTX_FLAG (rtl, used) = 1;
3262
3263 /* Set flags or add text to the name to record information, such as
3264 that it is a local symbol. If the name is changed, the macro
3265 ASM_OUTPUT_LABELREF will have to know how to strip this
3266 information. This call might invalidate our local variable
3267 SYMBOL; we can't use it afterward. */
3268 targetm.encode_section_info (exp, rtl, true);
3269
3270 desc->rtl = rtl;
3271
3272 return desc;
3273 }
3274
3275 /* Return an rtx representing a reference to constant data in memory
3276 for the constant expression EXP.
3277
3278 If assembler code for such a constant has already been output,
3279 return an rtx to refer to it.
3280 Otherwise, output such a constant in memory
3281 and generate an rtx for it.
3282
3283 If DEFER is nonzero, this constant can be deferred and output only
3284 if referenced in the function after all optimizations.
3285
3286 `const_desc_table' records which constants already have label strings. */
3287
3288 rtx
3289 output_constant_def (tree exp, int defer)
3290 {
3291 struct constant_descriptor_tree *desc;
3292 struct constant_descriptor_tree key;
3293 void **loc;
3294
3295 /* Look up EXP in the table of constant descriptors. If we didn't find
3296 it, create a new one. */
3297 key.value = exp;
3298 key.hash = const_hash_1 (exp);
3299 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3300
3301 desc = (struct constant_descriptor_tree *) *loc;
3302 if (desc == 0)
3303 {
3304 desc = build_constant_desc (exp);
3305 desc->hash = key.hash;
3306 *loc = desc;
3307 }
3308
3309 maybe_output_constant_def_contents (desc, defer);
3310 return desc->rtl;
3311 }
3312
3313 /* Subroutine of output_constant_def: Decide whether or not we need to
3314 output the constant DESC now, and if so, do it. */
3315 static void
3316 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3317 int defer)
3318 {
3319 rtx symbol = XEXP (desc->rtl, 0);
3320 tree exp = desc->value;
3321
3322 if (flag_syntax_only)
3323 return;
3324
3325 if (TREE_ASM_WRITTEN (exp))
3326 /* Already output; don't do it again. */
3327 return;
3328
3329 /* We can always defer constants as long as the context allows
3330 doing so. */
3331 if (defer)
3332 {
3333 /* Increment n_deferred_constants if it exists. It needs to be at
3334 least as large as the number of constants actually referred to
3335 by the function. If it's too small we'll stop looking too early
3336 and fail to emit constants; if it's too large we'll only look
3337 through the entire function when we could have stopped earlier. */
3338 if (cfun)
3339 n_deferred_constants++;
3340 return;
3341 }
3342
3343 output_constant_def_contents (symbol);
3344 }
3345
3346 /* Subroutine of output_constant_def_contents. Output the definition
3347 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3348 constant's alignment in bits. */
3349
3350 static void
3351 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3352 {
3353 HOST_WIDE_INT size;
3354
3355 size = get_constant_size (exp);
3356
3357 /* Do any machine/system dependent processing of the constant. */
3358 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3359
3360 /* Output the value of EXP. */
3361 output_constant (exp, size, align);
3362 }
3363
3364 /* We must output the constant data referred to by SYMBOL; do so. */
3365
3366 static void
3367 output_constant_def_contents (rtx symbol)
3368 {
3369 tree decl = SYMBOL_REF_DECL (symbol);
3370 tree exp = DECL_INITIAL (decl);
3371 unsigned int align;
3372 bool asan_protected = false;
3373
3374 /* Make sure any other constants whose addresses appear in EXP
3375 are assigned label numbers. */
3376 output_addressed_constants (exp);
3377
3378 /* We are no longer deferring this constant. */
3379 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3380
3381 if ((flag_sanitize & SANITIZE_ADDRESS)
3382 && TREE_CODE (exp) == STRING_CST
3383 && asan_protect_global (exp))
3384 {
3385 asan_protected = true;
3386 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
3387 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
3388 }
3389
3390 /* If the constant is part of an object block, make sure that the
3391 decl has been positioned within its block, but do not write out
3392 its definition yet. output_object_blocks will do that later. */
3393 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3394 place_block_symbol (symbol);
3395 else
3396 {
3397 align = DECL_ALIGN (decl);
3398 switch_to_section (get_constant_section (exp, align));
3399 if (align > BITS_PER_UNIT)
3400 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3401 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3402 if (asan_protected)
3403 {
3404 HOST_WIDE_INT size = get_constant_size (exp);
3405 assemble_zeros (asan_red_zone_size (size));
3406 }
3407 }
3408 if (flag_mudflap)
3409 mudflap_enqueue_constant (exp);
3410 }
3411
3412 /* Look up EXP in the table of constant descriptors. Return the rtl
3413 if it has been emitted, else null. */
3414
3415 rtx
3416 lookup_constant_def (tree exp)
3417 {
3418 struct constant_descriptor_tree *desc;
3419 struct constant_descriptor_tree key;
3420
3421 key.value = exp;
3422 key.hash = const_hash_1 (exp);
3423 desc = (struct constant_descriptor_tree *)
3424 htab_find_with_hash (const_desc_htab, &key, key.hash);
3425
3426 return (desc ? desc->rtl : NULL_RTX);
3427 }
3428
3429 /* Return a tree representing a reference to constant data in memory
3430 for the constant expression EXP.
3431
3432 This is the counterpart of output_constant_def at the Tree level. */
3433
3434 tree
3435 tree_output_constant_def (tree exp)
3436 {
3437 struct constant_descriptor_tree *desc, key;
3438 void **loc;
3439 tree decl;
3440
3441 /* Look up EXP in the table of constant descriptors. If we didn't find
3442 it, create a new one. */
3443 key.value = exp;
3444 key.hash = const_hash_1 (exp);
3445 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3446
3447 desc = (struct constant_descriptor_tree *) *loc;
3448 if (desc == 0)
3449 {
3450 desc = build_constant_desc (exp);
3451 desc->hash = key.hash;
3452 *loc = desc;
3453 }
3454
3455 decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3456 varpool_finalize_decl (decl);
3457 return decl;
3458 }
3459 \f
3460 /* Used in the hash tables to avoid outputting the same constant
3461 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3462 are output once per function, not once per file. */
3463 /* ??? Only a few targets need per-function constant pools. Most
3464 can use one per-file pool. Should add a targetm bit to tell the
3465 difference. */
3466
3467 struct GTY(()) rtx_constant_pool {
3468 /* Pointers to first and last constant in pool, as ordered by offset. */
3469 struct constant_descriptor_rtx *first;
3470 struct constant_descriptor_rtx *last;
3471
3472 /* Hash facility for making memory-constants from constant rtl-expressions.
3473 It is used on RISC machines where immediate integer arguments and
3474 constant addresses are restricted so that such constants must be stored
3475 in memory. */
3476 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_htab;
3477
3478 /* Current offset in constant pool (does not include any
3479 machine-specific header). */
3480 HOST_WIDE_INT offset;
3481 };
3482
3483 struct GTY((chain_next ("%h.next"))) constant_descriptor_rtx {
3484 struct constant_descriptor_rtx *next;
3485 rtx mem;
3486 rtx sym;
3487 rtx constant;
3488 HOST_WIDE_INT offset;
3489 hashval_t hash;
3490 enum machine_mode mode;
3491 unsigned int align;
3492 int labelno;
3493 int mark;
3494 };
3495
3496 /* Hash and compare functions for const_rtx_htab. */
3497
3498 static hashval_t
3499 const_desc_rtx_hash (const void *ptr)
3500 {
3501 const struct constant_descriptor_rtx *const desc
3502 = (const struct constant_descriptor_rtx *) ptr;
3503 return desc->hash;
3504 }
3505
3506 static int
3507 const_desc_rtx_eq (const void *a, const void *b)
3508 {
3509 const struct constant_descriptor_rtx *const x
3510 = (const struct constant_descriptor_rtx *) a;
3511 const struct constant_descriptor_rtx *const y
3512 = (const struct constant_descriptor_rtx *) b;
3513
3514 if (x->mode != y->mode)
3515 return 0;
3516 return rtx_equal_p (x->constant, y->constant);
3517 }
3518
3519 /* This is the worker function for const_rtx_hash, called via for_each_rtx. */
3520
3521 static int
3522 const_rtx_hash_1 (rtx *xp, void *data)
3523 {
3524 unsigned HOST_WIDE_INT hwi;
3525 enum machine_mode mode;
3526 enum rtx_code code;
3527 hashval_t h, *hp;
3528 rtx x;
3529
3530 x = *xp;
3531 code = GET_CODE (x);
3532 mode = GET_MODE (x);
3533 h = (hashval_t) code * 1048573 + mode;
3534
3535 switch (code)
3536 {
3537 case CONST_INT:
3538 hwi = INTVAL (x);
3539 fold_hwi:
3540 {
3541 int shift = sizeof (hashval_t) * CHAR_BIT;
3542 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3543 int i;
3544
3545 h ^= (hashval_t) hwi;
3546 for (i = 1; i < n; ++i)
3547 {
3548 hwi >>= shift;
3549 h ^= (hashval_t) hwi;
3550 }
3551 }
3552 break;
3553
3554 case CONST_DOUBLE:
3555 if (mode == VOIDmode)
3556 {
3557 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3558 goto fold_hwi;
3559 }
3560 else
3561 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3562 break;
3563
3564 case CONST_FIXED:
3565 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3566 break;
3567
3568 case CONST_VECTOR:
3569 {
3570 int i;
3571 for (i = XVECLEN (x, 0); i-- > 0; )
3572 h = h * 251 + const_rtx_hash_1 (&XVECEXP (x, 0, i), data);
3573 }
3574 break;
3575
3576 case SYMBOL_REF:
3577 h ^= htab_hash_string (XSTR (x, 0));
3578 break;
3579
3580 case LABEL_REF:
3581 h = h * 251 + CODE_LABEL_NUMBER (XEXP (x, 0));
3582 break;
3583
3584 case UNSPEC:
3585 case UNSPEC_VOLATILE:
3586 h = h * 251 + XINT (x, 1);
3587 break;
3588
3589 default:
3590 break;
3591 }
3592
3593 hp = (hashval_t *) data;
3594 *hp = *hp * 509 + h;
3595 return 0;
3596 }
3597
3598 /* Compute a hash value for X, which should be a constant. */
3599
3600 static hashval_t
3601 const_rtx_hash (rtx x)
3602 {
3603 hashval_t h = 0;
3604 for_each_rtx (&x, const_rtx_hash_1, &h);
3605 return h;
3606 }
3607
3608 \f
3609 /* Create and return a new rtx constant pool. */
3610
3611 static struct rtx_constant_pool *
3612 create_constant_pool (void)
3613 {
3614 struct rtx_constant_pool *pool;
3615
3616 pool = ggc_alloc_rtx_constant_pool ();
3617 pool->const_rtx_htab = htab_create_ggc (31, const_desc_rtx_hash,
3618 const_desc_rtx_eq, NULL);
3619 pool->first = NULL;
3620 pool->last = NULL;
3621 pool->offset = 0;
3622 return pool;
3623 }
3624
3625 /* Initialize constant pool hashing for a new function. */
3626
3627 void
3628 init_varasm_status (void)
3629 {
3630 crtl->varasm.pool = create_constant_pool ();
3631 crtl->varasm.deferred_constants = 0;
3632 }
3633 \f
3634 /* Given a MINUS expression, simplify it if both sides
3635 include the same symbol. */
3636
3637 rtx
3638 simplify_subtraction (rtx x)
3639 {
3640 rtx r = simplify_rtx (x);
3641 return r ? r : x;
3642 }
3643 \f
3644 /* Given a constant rtx X, make (or find) a memory constant for its value
3645 and return a MEM rtx to refer to it in memory. */
3646
3647 rtx
3648 force_const_mem (enum machine_mode mode, rtx x)
3649 {
3650 struct constant_descriptor_rtx *desc, tmp;
3651 struct rtx_constant_pool *pool;
3652 char label[256];
3653 rtx def, symbol;
3654 hashval_t hash;
3655 unsigned int align;
3656 void **slot;
3657
3658 /* If we're not allowed to drop X into the constant pool, don't. */
3659 if (targetm.cannot_force_const_mem (mode, x))
3660 return NULL_RTX;
3661
3662 /* Record that this function has used a constant pool entry. */
3663 crtl->uses_const_pool = 1;
3664
3665 /* Decide which pool to use. */
3666 pool = (targetm.use_blocks_for_constant_p (mode, x)
3667 ? shared_constant_pool
3668 : crtl->varasm.pool);
3669
3670 /* Lookup the value in the hashtable. */
3671 tmp.constant = x;
3672 tmp.mode = mode;
3673 hash = const_rtx_hash (x);
3674 slot = htab_find_slot_with_hash (pool->const_rtx_htab, &tmp, hash, INSERT);
3675 desc = (struct constant_descriptor_rtx *) *slot;
3676
3677 /* If the constant was already present, return its memory. */
3678 if (desc)
3679 return copy_rtx (desc->mem);
3680
3681 /* Otherwise, create a new descriptor. */
3682 desc = ggc_alloc_constant_descriptor_rtx ();
3683 *slot = desc;
3684
3685 /* Align the location counter as required by EXP's data type. */
3686 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3687 #ifdef CONSTANT_ALIGNMENT
3688 {
3689 tree type = lang_hooks.types.type_for_mode (mode, 0);
3690 if (type != NULL_TREE)
3691 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3692 }
3693 #endif
3694
3695 pool->offset += (align / BITS_PER_UNIT) - 1;
3696 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3697
3698 desc->next = NULL;
3699 desc->constant = copy_rtx (tmp.constant);
3700 desc->offset = pool->offset;
3701 desc->hash = hash;
3702 desc->mode = mode;
3703 desc->align = align;
3704 desc->labelno = const_labelno;
3705 desc->mark = 0;
3706
3707 pool->offset += GET_MODE_SIZE (mode);
3708 if (pool->last)
3709 pool->last->next = desc;
3710 else
3711 pool->first = pool->last = desc;
3712 pool->last = desc;
3713
3714 /* Create a string containing the label name, in LABEL. */
3715 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3716 ++const_labelno;
3717
3718 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3719 the constants pool. */
3720 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3721 {
3722 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3723 symbol = create_block_symbol (ggc_strdup (label),
3724 get_block_for_section (sect), -1);
3725 }
3726 else
3727 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3728 desc->sym = symbol;
3729 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3730 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3731 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3732
3733 /* Construct the MEM. */
3734 desc->mem = def = gen_const_mem (mode, symbol);
3735 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3736 set_mem_align (def, align);
3737
3738 /* If we're dropping a label to the constant pool, make sure we
3739 don't delete it. */
3740 if (GET_CODE (x) == LABEL_REF)
3741 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3742
3743 return copy_rtx (def);
3744 }
3745 \f
3746 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3747
3748 rtx
3749 get_pool_constant (rtx addr)
3750 {
3751 return SYMBOL_REF_CONSTANT (addr)->constant;
3752 }
3753
3754 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3755 and whether it has been output or not. */
3756
3757 rtx
3758 get_pool_constant_mark (rtx addr, bool *pmarked)
3759 {
3760 struct constant_descriptor_rtx *desc;
3761
3762 desc = SYMBOL_REF_CONSTANT (addr);
3763 *pmarked = (desc->mark != 0);
3764 return desc->constant;
3765 }
3766
3767 /* Similar, return the mode. */
3768
3769 enum machine_mode
3770 get_pool_mode (const_rtx addr)
3771 {
3772 return SYMBOL_REF_CONSTANT (addr)->mode;
3773 }
3774
3775 /* Return the size of the constant pool. */
3776
3777 int
3778 get_pool_size (void)
3779 {
3780 return crtl->varasm.pool->offset;
3781 }
3782 \f
3783 /* Worker function for output_constant_pool_1. Emit assembly for X
3784 in MODE with known alignment ALIGN. */
3785
3786 static void
3787 output_constant_pool_2 (enum machine_mode mode, rtx x, unsigned int align)
3788 {
3789 switch (GET_MODE_CLASS (mode))
3790 {
3791 case MODE_FLOAT:
3792 case MODE_DECIMAL_FLOAT:
3793 {
3794 REAL_VALUE_TYPE r;
3795
3796 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3797 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3798 assemble_real (r, mode, align);
3799 break;
3800 }
3801
3802 case MODE_INT:
3803 case MODE_PARTIAL_INT:
3804 case MODE_FRACT:
3805 case MODE_UFRACT:
3806 case MODE_ACCUM:
3807 case MODE_UACCUM:
3808 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3809 break;
3810
3811 case MODE_VECTOR_FLOAT:
3812 case MODE_VECTOR_INT:
3813 case MODE_VECTOR_FRACT:
3814 case MODE_VECTOR_UFRACT:
3815 case MODE_VECTOR_ACCUM:
3816 case MODE_VECTOR_UACCUM:
3817 {
3818 int i, units;
3819 enum machine_mode submode = GET_MODE_INNER (mode);
3820 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3821
3822 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3823 units = CONST_VECTOR_NUNITS (x);
3824
3825 for (i = 0; i < units; i++)
3826 {
3827 rtx elt = CONST_VECTOR_ELT (x, i);
3828 output_constant_pool_2 (submode, elt, i ? subalign : align);
3829 }
3830 }
3831 break;
3832
3833 default:
3834 gcc_unreachable ();
3835 }
3836 }
3837
3838 /* Worker function for output_constant_pool. Emit constant DESC,
3839 giving it ALIGN bits of alignment. */
3840
3841 static void
3842 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3843 unsigned int align)
3844 {
3845 rtx x, tmp;
3846
3847 x = desc->constant;
3848
3849 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3850 whose CODE_LABEL has been deleted. This can occur if a jump table
3851 is eliminated by optimization. If so, write a constant of zero
3852 instead. Note that this can also happen by turning the
3853 CODE_LABEL into a NOTE. */
3854 /* ??? This seems completely and utterly wrong. Certainly it's
3855 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3856 functioning even with INSN_DELETED_P and friends. */
3857
3858 tmp = x;
3859 switch (GET_CODE (tmp))
3860 {
3861 case CONST:
3862 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3863 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
3864 break;
3865 tmp = XEXP (XEXP (tmp, 0), 0);
3866 /* FALLTHRU */
3867
3868 case LABEL_REF:
3869 tmp = XEXP (tmp, 0);
3870 gcc_assert (!INSN_DELETED_P (tmp));
3871 gcc_assert (!NOTE_P (tmp)
3872 || NOTE_KIND (tmp) != NOTE_INSN_DELETED);
3873 break;
3874
3875 default:
3876 break;
3877 }
3878
3879 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3880 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3881 align, desc->labelno, done);
3882 #endif
3883
3884 assemble_align (align);
3885
3886 /* Output the label. */
3887 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3888
3889 /* Output the data. */
3890 output_constant_pool_2 (desc->mode, x, align);
3891
3892 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3893 sections have proper size. */
3894 if (align > GET_MODE_BITSIZE (desc->mode)
3895 && in_section
3896 && (in_section->common.flags & SECTION_MERGE))
3897 assemble_align (align);
3898
3899 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3900 done:
3901 #endif
3902 return;
3903 }
3904
3905 /* Given a SYMBOL_REF CURRENT_RTX, mark it and all constants it refers
3906 to as used. Emit referenced deferred strings. This function can
3907 be used with for_each_rtx to mark all SYMBOL_REFs in an rtx. */
3908
3909 static int
3910 mark_constant (rtx *current_rtx, void *data ATTRIBUTE_UNUSED)
3911 {
3912 rtx x = *current_rtx;
3913
3914 if (x == NULL_RTX || GET_CODE (x) != SYMBOL_REF)
3915 return 0;
3916
3917 if (CONSTANT_POOL_ADDRESS_P (x))
3918 {
3919 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
3920 if (desc->mark == 0)
3921 {
3922 desc->mark = 1;
3923 for_each_rtx (&desc->constant, mark_constant, NULL);
3924 }
3925 }
3926 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3927 {
3928 tree decl = SYMBOL_REF_DECL (x);
3929 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
3930 {
3931 n_deferred_constants--;
3932 output_constant_def_contents (x);
3933 }
3934 }
3935
3936 return -1;
3937 }
3938
3939 /* Look through appropriate parts of INSN, marking all entries in the
3940 constant pool which are actually being used. Entries that are only
3941 referenced by other constants are also marked as used. Emit
3942 deferred strings that are used. */
3943
3944 static void
3945 mark_constants (rtx insn)
3946 {
3947 if (!INSN_P (insn))
3948 return;
3949
3950 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3951 insns, not any notes that may be attached. We don't want to mark
3952 a constant just because it happens to appear in a REG_EQUIV note. */
3953 if (GET_CODE (PATTERN (insn)) == SEQUENCE)
3954 {
3955 rtx seq = PATTERN (insn);
3956 int i, n = XVECLEN (seq, 0);
3957 for (i = 0; i < n; ++i)
3958 {
3959 rtx subinsn = XVECEXP (seq, 0, i);
3960 if (INSN_P (subinsn))
3961 for_each_rtx (&PATTERN (subinsn), mark_constant, NULL);
3962 }
3963 }
3964 else
3965 for_each_rtx (&PATTERN (insn), mark_constant, NULL);
3966 }
3967
3968 /* Look through the instructions for this function, and mark all the
3969 entries in POOL which are actually being used. Emit deferred constants
3970 which have indeed been used. */
3971
3972 static void
3973 mark_constant_pool (void)
3974 {
3975 rtx insn;
3976
3977 if (!crtl->uses_const_pool && n_deferred_constants == 0)
3978 return;
3979
3980 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3981 mark_constants (insn);
3982 }
3983
3984 /* Write all the constants in POOL. */
3985
3986 static void
3987 output_constant_pool_contents (struct rtx_constant_pool *pool)
3988 {
3989 struct constant_descriptor_rtx *desc;
3990
3991 for (desc = pool->first; desc ; desc = desc->next)
3992 if (desc->mark)
3993 {
3994 /* If the constant is part of an object_block, make sure that
3995 the constant has been positioned within its block, but do not
3996 write out its definition yet. output_object_blocks will do
3997 that later. */
3998 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
3999 && SYMBOL_REF_BLOCK (desc->sym))
4000 place_block_symbol (desc->sym);
4001 else
4002 {
4003 switch_to_section (targetm.asm_out.select_rtx_section
4004 (desc->mode, desc->constant, desc->align));
4005 output_constant_pool_1 (desc, desc->align);
4006 }
4007 }
4008 }
4009
4010 /* Mark all constants that are used in the current function, then write
4011 out the function's private constant pool. */
4012
4013 static void
4014 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
4015 tree fndecl ATTRIBUTE_UNUSED)
4016 {
4017 struct rtx_constant_pool *pool = crtl->varasm.pool;
4018
4019 /* It is possible for gcc to call force_const_mem and then to later
4020 discard the instructions which refer to the constant. In such a
4021 case we do not need to output the constant. */
4022 mark_constant_pool ();
4023
4024 #ifdef ASM_OUTPUT_POOL_PROLOGUE
4025 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
4026 #endif
4027
4028 output_constant_pool_contents (pool);
4029
4030 #ifdef ASM_OUTPUT_POOL_EPILOGUE
4031 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
4032 #endif
4033 }
4034 \f
4035 /* Write the contents of the shared constant pool. */
4036
4037 void
4038 output_shared_constant_pool (void)
4039 {
4040 output_constant_pool_contents (shared_constant_pool);
4041 }
4042 \f
4043 /* Determine what kind of relocations EXP may need. */
4044
4045 int
4046 compute_reloc_for_constant (tree exp)
4047 {
4048 int reloc = 0, reloc2;
4049 tree tem;
4050
4051 switch (TREE_CODE (exp))
4052 {
4053 case ADDR_EXPR:
4054 case FDESC_EXPR:
4055 /* Go inside any operations that get_inner_reference can handle and see
4056 if what's inside is a constant: no need to do anything here for
4057 addresses of variables or functions. */
4058 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4059 tem = TREE_OPERAND (tem, 0))
4060 ;
4061
4062 if (TREE_CODE (tem) == MEM_REF
4063 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4064 {
4065 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4066 break;
4067 }
4068
4069 if (TREE_PUBLIC (tem))
4070 reloc |= 2;
4071 else
4072 reloc |= 1;
4073 break;
4074
4075 case PLUS_EXPR:
4076 case POINTER_PLUS_EXPR:
4077 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4078 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4079 break;
4080
4081 case MINUS_EXPR:
4082 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4083 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4084 /* The difference of two local labels is computable at link time. */
4085 if (reloc == 1 && reloc2 == 1)
4086 reloc = 0;
4087 else
4088 reloc |= reloc2;
4089 break;
4090
4091 CASE_CONVERT:
4092 case VIEW_CONVERT_EXPR:
4093 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4094 break;
4095
4096 case CONSTRUCTOR:
4097 {
4098 unsigned HOST_WIDE_INT idx;
4099 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4100 if (tem != 0)
4101 reloc |= compute_reloc_for_constant (tem);
4102 }
4103 break;
4104
4105 default:
4106 break;
4107 }
4108 return reloc;
4109 }
4110
4111 /* Find all the constants whose addresses are referenced inside of EXP,
4112 and make sure assembler code with a label has been output for each one.
4113 Indicate whether an ADDR_EXPR has been encountered. */
4114
4115 static void
4116 output_addressed_constants (tree exp)
4117 {
4118 tree tem;
4119
4120 switch (TREE_CODE (exp))
4121 {
4122 case ADDR_EXPR:
4123 case FDESC_EXPR:
4124 /* Go inside any operations that get_inner_reference can handle and see
4125 if what's inside is a constant: no need to do anything here for
4126 addresses of variables or functions. */
4127 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4128 tem = TREE_OPERAND (tem, 0))
4129 ;
4130
4131 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4132 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4133 tem = DECL_INITIAL (tem);
4134
4135 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4136 output_constant_def (tem, 0);
4137
4138 if (TREE_CODE (tem) == MEM_REF)
4139 output_addressed_constants (TREE_OPERAND (tem, 0));
4140 break;
4141
4142 case PLUS_EXPR:
4143 case POINTER_PLUS_EXPR:
4144 case MINUS_EXPR:
4145 output_addressed_constants (TREE_OPERAND (exp, 1));
4146 /* Fall through. */
4147
4148 CASE_CONVERT:
4149 case VIEW_CONVERT_EXPR:
4150 output_addressed_constants (TREE_OPERAND (exp, 0));
4151 break;
4152
4153 case CONSTRUCTOR:
4154 {
4155 unsigned HOST_WIDE_INT idx;
4156 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4157 if (tem != 0)
4158 output_addressed_constants (tem);
4159 }
4160 break;
4161
4162 default:
4163 break;
4164 }
4165 }
4166 \f
4167 /* Whether a constructor CTOR is a valid static constant initializer if all
4168 its elements are. This used to be internal to initializer_constant_valid_p
4169 and has been exposed to let other functions like categorize_ctor_elements
4170 evaluate the property while walking a constructor for other purposes. */
4171
4172 bool
4173 constructor_static_from_elts_p (const_tree ctor)
4174 {
4175 return (TREE_CONSTANT (ctor)
4176 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4177 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4178 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4179 }
4180
4181 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4182 tree *cache);
4183
4184 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4185 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4186 which are valid when ENDTYPE is an integer of any size; in
4187 particular, this does not accept a pointer minus a constant. This
4188 returns null_pointer_node if the VALUE is an absolute constant
4189 which can be used to initialize a static variable. Otherwise it
4190 returns NULL. */
4191
4192 static tree
4193 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4194 {
4195 tree op0, op1;
4196
4197 if (!INTEGRAL_TYPE_P (endtype))
4198 return NULL_TREE;
4199
4200 op0 = TREE_OPERAND (value, 0);
4201 op1 = TREE_OPERAND (value, 1);
4202
4203 /* Like STRIP_NOPS except allow the operand mode to widen. This
4204 works around a feature of fold that simplifies (int)(p1 - p2) to
4205 ((int)p1 - (int)p2) under the theory that the narrower operation
4206 is cheaper. */
4207
4208 while (CONVERT_EXPR_P (op0)
4209 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4210 {
4211 tree inner = TREE_OPERAND (op0, 0);
4212 if (inner == error_mark_node
4213 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4214 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
4215 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4216 break;
4217 op0 = inner;
4218 }
4219
4220 while (CONVERT_EXPR_P (op1)
4221 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4222 {
4223 tree inner = TREE_OPERAND (op1, 0);
4224 if (inner == error_mark_node
4225 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4226 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
4227 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4228 break;
4229 op1 = inner;
4230 }
4231
4232 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4233 if (!op0)
4234 return NULL_TREE;
4235
4236 op1 = initializer_constant_valid_p_1 (op1, endtype,
4237 cache ? cache + 2 : NULL);
4238 /* Both initializers must be known. */
4239 if (op1)
4240 {
4241 if (op0 == op1
4242 && (op0 == null_pointer_node
4243 || TREE_CODE (value) == MINUS_EXPR))
4244 return null_pointer_node;
4245
4246 /* Support differences between labels. */
4247 if (TREE_CODE (op0) == LABEL_DECL
4248 && TREE_CODE (op1) == LABEL_DECL)
4249 return null_pointer_node;
4250
4251 if (TREE_CODE (op0) == STRING_CST
4252 && TREE_CODE (op1) == STRING_CST
4253 && operand_equal_p (op0, op1, 1))
4254 return null_pointer_node;
4255 }
4256
4257 return NULL_TREE;
4258 }
4259
4260 /* Helper function of initializer_constant_valid_p.
4261 Return nonzero if VALUE is a valid constant-valued expression
4262 for use in initializing a static variable; one that can be an
4263 element of a "constant" initializer.
4264
4265 Return null_pointer_node if the value is absolute;
4266 if it is relocatable, return the variable that determines the relocation.
4267 We assume that VALUE has been folded as much as possible;
4268 therefore, we do not need to check for such things as
4269 arithmetic-combinations of integers.
4270
4271 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4272
4273 static tree
4274 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4275 {
4276 tree ret;
4277
4278 switch (TREE_CODE (value))
4279 {
4280 case CONSTRUCTOR:
4281 if (constructor_static_from_elts_p (value))
4282 {
4283 unsigned HOST_WIDE_INT idx;
4284 tree elt;
4285 bool absolute = true;
4286
4287 if (cache && cache[0] == value)
4288 return cache[1];
4289 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4290 {
4291 tree reloc;
4292 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4293 NULL);
4294 if (!reloc)
4295 {
4296 if (cache)
4297 {
4298 cache[0] = value;
4299 cache[1] = NULL_TREE;
4300 }
4301 return NULL_TREE;
4302 }
4303 if (reloc != null_pointer_node)
4304 absolute = false;
4305 }
4306 /* For a non-absolute relocation, there is no single
4307 variable that can be "the variable that determines the
4308 relocation." */
4309 if (cache)
4310 {
4311 cache[0] = value;
4312 cache[1] = absolute ? null_pointer_node : error_mark_node;
4313 }
4314 return absolute ? null_pointer_node : error_mark_node;
4315 }
4316
4317 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4318
4319 case INTEGER_CST:
4320 case VECTOR_CST:
4321 case REAL_CST:
4322 case FIXED_CST:
4323 case STRING_CST:
4324 case COMPLEX_CST:
4325 return null_pointer_node;
4326
4327 case ADDR_EXPR:
4328 case FDESC_EXPR:
4329 {
4330 tree op0 = staticp (TREE_OPERAND (value, 0));
4331 if (op0)
4332 {
4333 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4334 to be a constant, this is old-skool offsetof-like nonsense. */
4335 if (TREE_CODE (op0) == INDIRECT_REF
4336 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4337 return null_pointer_node;
4338 /* Taking the address of a nested function involves a trampoline,
4339 unless we don't need or want one. */
4340 if (TREE_CODE (op0) == FUNCTION_DECL
4341 && DECL_STATIC_CHAIN (op0)
4342 && !TREE_NO_TRAMPOLINE (value))
4343 return NULL_TREE;
4344 /* "&{...}" requires a temporary to hold the constructed
4345 object. */
4346 if (TREE_CODE (op0) == CONSTRUCTOR)
4347 return NULL_TREE;
4348 }
4349 return op0;
4350 }
4351
4352 case NON_LVALUE_EXPR:
4353 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4354 endtype, cache);
4355
4356 case VIEW_CONVERT_EXPR:
4357 {
4358 tree src = TREE_OPERAND (value, 0);
4359 tree src_type = TREE_TYPE (src);
4360 tree dest_type = TREE_TYPE (value);
4361
4362 /* Allow view-conversions from aggregate to non-aggregate type only
4363 if the bit pattern is fully preserved afterwards; otherwise, the
4364 RTL expander won't be able to apply a subsequent transformation
4365 to the underlying constructor. */
4366 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4367 {
4368 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4369 return initializer_constant_valid_p_1 (src, endtype, cache);
4370 else
4371 return NULL_TREE;
4372 }
4373
4374 /* Allow all other kinds of view-conversion. */
4375 return initializer_constant_valid_p_1 (src, endtype, cache);
4376 }
4377
4378 CASE_CONVERT:
4379 {
4380 tree src = TREE_OPERAND (value, 0);
4381 tree src_type = TREE_TYPE (src);
4382 tree dest_type = TREE_TYPE (value);
4383
4384 /* Allow conversions between pointer types, floating-point
4385 types, and offset types. */
4386 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4387 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4388 || (TREE_CODE (dest_type) == OFFSET_TYPE
4389 && TREE_CODE (src_type) == OFFSET_TYPE))
4390 return initializer_constant_valid_p_1 (src, endtype, cache);
4391
4392 /* Allow length-preserving conversions between integer types. */
4393 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4394 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4395 return initializer_constant_valid_p_1 (src, endtype, cache);
4396
4397 /* Allow conversions between other integer types only if
4398 explicit value. */
4399 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type))
4400 {
4401 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4402 if (inner == null_pointer_node)
4403 return null_pointer_node;
4404 break;
4405 }
4406
4407 /* Allow (int) &foo provided int is as wide as a pointer. */
4408 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4409 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4410 return initializer_constant_valid_p_1 (src, endtype, cache);
4411
4412 /* Likewise conversions from int to pointers, but also allow
4413 conversions from 0. */
4414 if ((POINTER_TYPE_P (dest_type)
4415 || TREE_CODE (dest_type) == OFFSET_TYPE)
4416 && INTEGRAL_TYPE_P (src_type))
4417 {
4418 if (TREE_CODE (src) == INTEGER_CST
4419 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4420 return null_pointer_node;
4421 if (integer_zerop (src))
4422 return null_pointer_node;
4423 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4424 return initializer_constant_valid_p_1 (src, endtype, cache);
4425 }
4426
4427 /* Allow conversions to struct or union types if the value
4428 inside is okay. */
4429 if (TREE_CODE (dest_type) == RECORD_TYPE
4430 || TREE_CODE (dest_type) == UNION_TYPE)
4431 return initializer_constant_valid_p_1 (src, endtype, cache);
4432 }
4433 break;
4434
4435 case POINTER_PLUS_EXPR:
4436 case PLUS_EXPR:
4437 /* Any valid floating-point constants will have been folded by now;
4438 with -frounding-math we hit this with addition of two constants. */
4439 if (TREE_CODE (endtype) == REAL_TYPE)
4440 return NULL_TREE;
4441 if (cache && cache[0] == value)
4442 return cache[1];
4443 if (! INTEGRAL_TYPE_P (endtype)
4444 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4445 {
4446 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4447 tree valid0
4448 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4449 endtype, ncache);
4450 tree valid1
4451 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4452 endtype, ncache + 2);
4453 /* If either term is absolute, use the other term's relocation. */
4454 if (valid0 == null_pointer_node)
4455 ret = valid1;
4456 else if (valid1 == null_pointer_node)
4457 ret = valid0;
4458 /* Support narrowing pointer differences. */
4459 else
4460 ret = narrowing_initializer_constant_valid_p (value, endtype,
4461 ncache);
4462 }
4463 else
4464 /* Support narrowing pointer differences. */
4465 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4466 if (cache)
4467 {
4468 cache[0] = value;
4469 cache[1] = ret;
4470 }
4471 return ret;
4472
4473 case MINUS_EXPR:
4474 if (TREE_CODE (endtype) == REAL_TYPE)
4475 return NULL_TREE;
4476 if (cache && cache[0] == value)
4477 return cache[1];
4478 if (! INTEGRAL_TYPE_P (endtype)
4479 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4480 {
4481 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4482 tree valid0
4483 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4484 endtype, ncache);
4485 tree valid1
4486 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4487 endtype, ncache + 2);
4488 /* Win if second argument is absolute. */
4489 if (valid1 == null_pointer_node)
4490 ret = valid0;
4491 /* Win if both arguments have the same relocation.
4492 Then the value is absolute. */
4493 else if (valid0 == valid1 && valid0 != 0)
4494 ret = null_pointer_node;
4495 /* Since GCC guarantees that string constants are unique in the
4496 generated code, a subtraction between two copies of the same
4497 constant string is absolute. */
4498 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4499 && valid1 && TREE_CODE (valid1) == STRING_CST
4500 && operand_equal_p (valid0, valid1, 1))
4501 ret = null_pointer_node;
4502 /* Support narrowing differences. */
4503 else
4504 ret = narrowing_initializer_constant_valid_p (value, endtype,
4505 ncache);
4506 }
4507 else
4508 /* Support narrowing differences. */
4509 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4510 if (cache)
4511 {
4512 cache[0] = value;
4513 cache[1] = ret;
4514 }
4515 return ret;
4516
4517 default:
4518 break;
4519 }
4520
4521 return NULL_TREE;
4522 }
4523
4524 /* Return nonzero if VALUE is a valid constant-valued expression
4525 for use in initializing a static variable; one that can be an
4526 element of a "constant" initializer.
4527
4528 Return null_pointer_node if the value is absolute;
4529 if it is relocatable, return the variable that determines the relocation.
4530 We assume that VALUE has been folded as much as possible;
4531 therefore, we do not need to check for such things as
4532 arithmetic-combinations of integers. */
4533 tree
4534 initializer_constant_valid_p (tree value, tree endtype)
4535 {
4536 return initializer_constant_valid_p_1 (value, endtype, NULL);
4537 }
4538 \f
4539 /* Return true if VALUE is a valid constant-valued expression
4540 for use in initializing a static bit-field; one that can be
4541 an element of a "constant" initializer. */
4542
4543 bool
4544 initializer_constant_valid_for_bitfield_p (tree value)
4545 {
4546 /* For bitfields we support integer constants or possibly nested aggregates
4547 of such. */
4548 switch (TREE_CODE (value))
4549 {
4550 case CONSTRUCTOR:
4551 {
4552 unsigned HOST_WIDE_INT idx;
4553 tree elt;
4554
4555 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4556 if (!initializer_constant_valid_for_bitfield_p (elt))
4557 return false;
4558 return true;
4559 }
4560
4561 case INTEGER_CST:
4562 case REAL_CST:
4563 return true;
4564
4565 case VIEW_CONVERT_EXPR:
4566 case NON_LVALUE_EXPR:
4567 return
4568 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4569
4570 default:
4571 break;
4572 }
4573
4574 return false;
4575 }
4576
4577 /* output_constructor outer state of relevance in recursive calls, typically
4578 for nested aggregate bitfields. */
4579
4580 typedef struct {
4581 unsigned int bit_offset; /* current position in ... */
4582 int byte; /* ... the outer byte buffer. */
4583 } oc_outer_state;
4584
4585 static unsigned HOST_WIDE_INT
4586 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int,
4587 oc_outer_state *);
4588
4589 /* Output assembler code for constant EXP, with no label.
4590 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4591 Assumes output_addressed_constants has been done on EXP already.
4592
4593 Generate exactly SIZE bytes of assembler data, padding at the end
4594 with zeros if necessary. SIZE must always be specified.
4595
4596 SIZE is important for structure constructors,
4597 since trailing members may have been omitted from the constructor.
4598 It is also important for initialization of arrays from string constants
4599 since the full length of the string constant might not be wanted.
4600 It is also needed for initialization of unions, where the initializer's
4601 type is just one member, and that may not be as long as the union.
4602
4603 There a case in which we would fail to output exactly SIZE bytes:
4604 for a structure constructor that wants to produce more than SIZE bytes.
4605 But such constructors will never be generated for any possible input.
4606
4607 ALIGN is the alignment of the data in bits. */
4608
4609 void
4610 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align)
4611 {
4612 enum tree_code code;
4613 unsigned HOST_WIDE_INT thissize;
4614
4615 if (size == 0 || flag_syntax_only)
4616 return;
4617
4618 /* See if we're trying to initialize a pointer in a non-default mode
4619 to the address of some declaration somewhere. If the target says
4620 the mode is valid for pointers, assume the target has a way of
4621 resolving it. */
4622 if (TREE_CODE (exp) == NOP_EXPR
4623 && POINTER_TYPE_P (TREE_TYPE (exp))
4624 && targetm.addr_space.valid_pointer_mode
4625 (TYPE_MODE (TREE_TYPE (exp)),
4626 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4627 {
4628 tree saved_type = TREE_TYPE (exp);
4629
4630 /* Peel off any intermediate conversions-to-pointer for valid
4631 pointer modes. */
4632 while (TREE_CODE (exp) == NOP_EXPR
4633 && POINTER_TYPE_P (TREE_TYPE (exp))
4634 && targetm.addr_space.valid_pointer_mode
4635 (TYPE_MODE (TREE_TYPE (exp)),
4636 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4637 exp = TREE_OPERAND (exp, 0);
4638
4639 /* If what we're left with is the address of something, we can
4640 convert the address to the final type and output it that
4641 way. */
4642 if (TREE_CODE (exp) == ADDR_EXPR)
4643 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4644 /* Likewise for constant ints. */
4645 else if (TREE_CODE (exp) == INTEGER_CST)
4646 exp = build_int_cst_wide (saved_type, TREE_INT_CST_LOW (exp),
4647 TREE_INT_CST_HIGH (exp));
4648
4649 }
4650
4651 /* Eliminate any conversions since we'll be outputting the underlying
4652 constant. */
4653 while (CONVERT_EXPR_P (exp)
4654 || TREE_CODE (exp) == NON_LVALUE_EXPR
4655 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4656 {
4657 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4658 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4659
4660 /* Make sure eliminating the conversion is really a no-op, except with
4661 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4662 union types to allow for Ada unchecked unions. */
4663 if (type_size > op_size
4664 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4665 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4666 /* Keep the conversion. */
4667 break;
4668 else
4669 exp = TREE_OPERAND (exp, 0);
4670 }
4671
4672 code = TREE_CODE (TREE_TYPE (exp));
4673 thissize = int_size_in_bytes (TREE_TYPE (exp));
4674
4675 /* Allow a constructor with no elements for any data type.
4676 This means to fill the space with zeros. */
4677 if (TREE_CODE (exp) == CONSTRUCTOR
4678 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4679 {
4680 assemble_zeros (size);
4681 return;
4682 }
4683
4684 if (TREE_CODE (exp) == FDESC_EXPR)
4685 {
4686 #ifdef ASM_OUTPUT_FDESC
4687 HOST_WIDE_INT part = tree_low_cst (TREE_OPERAND (exp, 1), 0);
4688 tree decl = TREE_OPERAND (exp, 0);
4689 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4690 #else
4691 gcc_unreachable ();
4692 #endif
4693 return;
4694 }
4695
4696 /* Now output the underlying data. If we've handling the padding, return.
4697 Otherwise, break and ensure SIZE is the size written. */
4698 switch (code)
4699 {
4700 case BOOLEAN_TYPE:
4701 case INTEGER_TYPE:
4702 case ENUMERAL_TYPE:
4703 case POINTER_TYPE:
4704 case REFERENCE_TYPE:
4705 case OFFSET_TYPE:
4706 case FIXED_POINT_TYPE:
4707 case POINTER_BOUNDS_TYPE:
4708 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
4709 EXPAND_INITIALIZER),
4710 MIN (size, thissize), align, 0))
4711 error ("initializer for integer/fixed-point value is too complicated");
4712 break;
4713
4714 case REAL_TYPE:
4715 if (TREE_CODE (exp) != REAL_CST)
4716 error ("initializer for floating value is not a floating constant");
4717 else
4718 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)), align);
4719 break;
4720
4721 case COMPLEX_TYPE:
4722 output_constant (TREE_REALPART (exp), thissize / 2, align);
4723 output_constant (TREE_IMAGPART (exp), thissize / 2,
4724 min_align (align, BITS_PER_UNIT * (thissize / 2)));
4725 break;
4726
4727 case ARRAY_TYPE:
4728 case VECTOR_TYPE:
4729 switch (TREE_CODE (exp))
4730 {
4731 case CONSTRUCTOR:
4732 output_constructor (exp, size, align, NULL);
4733 return;
4734 case STRING_CST:
4735 thissize
4736 = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4737 assemble_string (TREE_STRING_POINTER (exp), thissize);
4738 break;
4739 case VECTOR_CST:
4740 {
4741 enum machine_mode inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4742 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4743 int elt_size = GET_MODE_SIZE (inner);
4744 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align);
4745 thissize = elt_size;
4746 for (unsigned int i = 1; i < VECTOR_CST_NELTS (exp); i++)
4747 {
4748 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign);
4749 thissize += elt_size;
4750 }
4751 break;
4752 }
4753 default:
4754 gcc_unreachable ();
4755 }
4756 break;
4757
4758 case RECORD_TYPE:
4759 case UNION_TYPE:
4760 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4761 output_constructor (exp, size, align, NULL);
4762 return;
4763
4764 case ERROR_MARK:
4765 return;
4766
4767 default:
4768 gcc_unreachable ();
4769 }
4770
4771 if (size > thissize)
4772 assemble_zeros (size - thissize);
4773 }
4774
4775 \f
4776 /* Subroutine of output_constructor, used for computing the size of
4777 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4778 type with an unspecified upper bound. */
4779
4780 static unsigned HOST_WIDE_INT
4781 array_size_for_constructor (tree val)
4782 {
4783 tree max_index;
4784 unsigned HOST_WIDE_INT cnt;
4785 tree index, value, tmp;
4786 double_int i;
4787
4788 /* This code used to attempt to handle string constants that are not
4789 arrays of single-bytes, but nothing else does, so there's no point in
4790 doing it here. */
4791 if (TREE_CODE (val) == STRING_CST)
4792 return TREE_STRING_LENGTH (val);
4793
4794 max_index = NULL_TREE;
4795 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
4796 {
4797 if (TREE_CODE (index) == RANGE_EXPR)
4798 index = TREE_OPERAND (index, 1);
4799 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
4800 max_index = index;
4801 }
4802
4803 if (max_index == NULL_TREE)
4804 return 0;
4805
4806 /* Compute the total number of array elements. */
4807 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
4808 i = tree_to_double_int (max_index) - tree_to_double_int (tmp);
4809 i += double_int_one;
4810
4811 /* Multiply by the array element unit size to find number of bytes. */
4812 i *= tree_to_double_int (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
4813
4814 gcc_assert (i.fits_uhwi ());
4815 return i.low;
4816 }
4817
4818 /* Other datastructures + helpers for output_constructor. */
4819
4820 /* output_constructor local state to support interaction with helpers. */
4821
4822 typedef struct {
4823
4824 /* Received arguments. */
4825 tree exp; /* Constructor expression. */
4826 tree type; /* Type of constructor expression. */
4827 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */
4828 unsigned int align; /* Known initial alignment. */
4829 tree min_index; /* Lower bound if specified for an array. */
4830
4831 /* Output processing state. */
4832 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */
4833 int byte; /* Part of a bitfield byte yet to be output. */
4834 int last_relative_index; /* Implicit or explicit index of the last
4835 array element output within a bitfield. */
4836 bool byte_buffer_in_use; /* Whether BYTE is in use. */
4837
4838 /* Current element. */
4839 tree field; /* Current field decl in a record. */
4840 tree val; /* Current element value. */
4841 tree index; /* Current element index. */
4842
4843 } oc_local_state;
4844
4845 /* Helper for output_constructor. From the current LOCAL state, output a
4846 RANGE_EXPR element. */
4847
4848 static void
4849 output_constructor_array_range (oc_local_state *local)
4850 {
4851 unsigned HOST_WIDE_INT fieldsize
4852 = int_size_in_bytes (TREE_TYPE (local->type));
4853
4854 HOST_WIDE_INT lo_index
4855 = tree_low_cst (TREE_OPERAND (local->index, 0), 0);
4856 HOST_WIDE_INT hi_index
4857 = tree_low_cst (TREE_OPERAND (local->index, 1), 0);
4858 HOST_WIDE_INT index;
4859
4860 unsigned int align2
4861 = min_align (local->align, fieldsize * BITS_PER_UNIT);
4862
4863 for (index = lo_index; index <= hi_index; index++)
4864 {
4865 /* Output the element's initial value. */
4866 if (local->val == NULL_TREE)
4867 assemble_zeros (fieldsize);
4868 else
4869 output_constant (local->val, fieldsize, align2);
4870
4871 /* Count its size. */
4872 local->total_bytes += fieldsize;
4873 }
4874 }
4875
4876 /* Helper for output_constructor. From the current LOCAL state, output a
4877 field element that is not true bitfield or part of an outer one. */
4878
4879 static void
4880 output_constructor_regular_field (oc_local_state *local)
4881 {
4882 /* Field size and position. Since this structure is static, we know the
4883 positions are constant. */
4884 unsigned HOST_WIDE_INT fieldsize;
4885 HOST_WIDE_INT fieldpos;
4886
4887 unsigned int align2;
4888
4889 if (local->index != NULL_TREE)
4890 {
4891 /* Perform the index calculation in modulo arithmetic but
4892 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
4893 but we are using an unsigned sizetype. */
4894 unsigned prec = TYPE_PRECISION (sizetype);
4895 double_int idx = tree_to_double_int (local->index)
4896 - tree_to_double_int (local->min_index);
4897 idx = idx.sext (prec);
4898 fieldpos = (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (local->val)), 1)
4899 * idx.low);
4900 }
4901 else if (local->field != NULL_TREE)
4902 fieldpos = int_byte_position (local->field);
4903 else
4904 fieldpos = 0;
4905
4906 /* Output any buffered-up bit-fields preceding this element. */
4907 if (local->byte_buffer_in_use)
4908 {
4909 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4910 local->total_bytes++;
4911 local->byte_buffer_in_use = false;
4912 }
4913
4914 /* Advance to offset of this element.
4915 Note no alignment needed in an array, since that is guaranteed
4916 if each element has the proper size. */
4917 if ((local->field != NULL_TREE || local->index != NULL_TREE)
4918 && fieldpos != local->total_bytes)
4919 {
4920 gcc_assert (fieldpos >= local->total_bytes);
4921 assemble_zeros (fieldpos - local->total_bytes);
4922 local->total_bytes = fieldpos;
4923 }
4924
4925 /* Find the alignment of this element. */
4926 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
4927
4928 /* Determine size this element should occupy. */
4929 if (local->field)
4930 {
4931 fieldsize = 0;
4932
4933 /* If this is an array with an unspecified upper bound,
4934 the initializer determines the size. */
4935 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
4936 but we cannot do this until the deprecated support for
4937 initializing zero-length array members is removed. */
4938 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
4939 && TYPE_DOMAIN (TREE_TYPE (local->field))
4940 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field))))
4941 {
4942 fieldsize = array_size_for_constructor (local->val);
4943 /* Given a non-empty initialization, this field had
4944 better be last. */
4945 gcc_assert (!fieldsize || !DECL_CHAIN (local->field));
4946 }
4947 else
4948 fieldsize = tree_low_cst (DECL_SIZE_UNIT (local->field), 1);
4949 }
4950 else
4951 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
4952
4953 /* Output the element's initial value. */
4954 if (local->val == NULL_TREE)
4955 assemble_zeros (fieldsize);
4956 else
4957 output_constant (local->val, fieldsize, align2);
4958
4959 /* Count its size. */
4960 local->total_bytes += fieldsize;
4961 }
4962
4963 /* Helper for output_constructor. From the LOCAL state, output an element
4964 that is a true bitfield or part of an outer one. BIT_OFFSET is the offset
4965 from the start of a possibly ongoing outer byte buffer. */
4966
4967 static void
4968 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
4969 {
4970 /* Bit size of this element. */
4971 HOST_WIDE_INT ebitsize
4972 = (local->field
4973 ? tree_low_cst (DECL_SIZE (local->field), 1)
4974 : tree_low_cst (TYPE_SIZE (TREE_TYPE (local->type)), 1));
4975
4976 /* Relative index of this element if this is an array component. */
4977 HOST_WIDE_INT relative_index
4978 = (!local->field
4979 ? (local->index
4980 ? (tree_low_cst (local->index, 0)
4981 - tree_low_cst (local->min_index, 0))
4982 : local->last_relative_index + 1)
4983 : 0);
4984
4985 /* Bit position of this element from the start of the containing
4986 constructor. */
4987 HOST_WIDE_INT constructor_relative_ebitpos
4988 = (local->field
4989 ? int_bit_position (local->field)
4990 : ebitsize * relative_index);
4991
4992 /* Bit position of this element from the start of a possibly ongoing
4993 outer byte buffer. */
4994 HOST_WIDE_INT byte_relative_ebitpos
4995 = bit_offset + constructor_relative_ebitpos;
4996
4997 /* From the start of a possibly ongoing outer byte buffer, offsets to
4998 the first bit of this element and to the first bit past the end of
4999 this element. */
5000 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
5001 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
5002
5003 local->last_relative_index = relative_index;
5004
5005 if (local->val == NULL_TREE)
5006 local->val = integer_zero_node;
5007
5008 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
5009 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
5010 local->val = TREE_OPERAND (local->val, 0);
5011
5012 if (TREE_CODE (local->val) != INTEGER_CST
5013 && TREE_CODE (local->val) != CONSTRUCTOR)
5014 {
5015 error ("invalid initial value for member %qE", DECL_NAME (local->field));
5016 return;
5017 }
5018
5019 /* If this field does not start in this (or next) byte, skip some bytes. */
5020 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5021 {
5022 /* Output remnant of any bit field in previous bytes. */
5023 if (local->byte_buffer_in_use)
5024 {
5025 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5026 local->total_bytes++;
5027 local->byte_buffer_in_use = false;
5028 }
5029
5030 /* If still not at proper byte, advance to there. */
5031 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5032 {
5033 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
5034 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
5035 local->total_bytes = next_offset / BITS_PER_UNIT;
5036 }
5037 }
5038
5039 /* Set up the buffer if necessary. */
5040 if (!local->byte_buffer_in_use)
5041 {
5042 local->byte = 0;
5043 if (ebitsize > 0)
5044 local->byte_buffer_in_use = true;
5045 }
5046
5047 /* If this is nested constructor, recurse passing the bit offset and the
5048 pending data, then retrieve the new pending data afterwards. */
5049 if (TREE_CODE (local->val) == CONSTRUCTOR)
5050 {
5051 oc_outer_state temp_state;
5052 temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5053 temp_state.byte = local->byte;
5054 local->total_bytes
5055 += output_constructor (local->val, 0, 0, &temp_state);
5056 local->byte = temp_state.byte;
5057 return;
5058 }
5059
5060 /* Otherwise, we must split the element into pieces that fall within
5061 separate bytes, and combine each byte with previous or following
5062 bit-fields. */
5063 while (next_offset < end_offset)
5064 {
5065 int this_time;
5066 int shift;
5067 HOST_WIDE_INT value;
5068 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5069 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5070
5071 /* Advance from byte to byte within this element when necessary. */
5072 while (next_byte != local->total_bytes)
5073 {
5074 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5075 local->total_bytes++;
5076 local->byte = 0;
5077 }
5078
5079 /* Number of bits we can process at once (all part of the same byte). */
5080 this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5081 if (BYTES_BIG_ENDIAN)
5082 {
5083 /* On big-endian machine, take the most significant bits
5084 first (of the bits that are significant)
5085 and put them into bytes from the most significant end. */
5086 shift = end_offset - next_offset - this_time;
5087
5088 /* Don't try to take a bunch of bits that cross
5089 the word boundary in the INTEGER_CST. We can
5090 only select bits from the LOW or HIGH part
5091 not from both. */
5092 if (shift < HOST_BITS_PER_WIDE_INT
5093 && shift + this_time > HOST_BITS_PER_WIDE_INT)
5094 {
5095 this_time = shift + this_time - HOST_BITS_PER_WIDE_INT;
5096 shift = HOST_BITS_PER_WIDE_INT;
5097 }
5098
5099 /* Now get the bits from the appropriate constant word. */
5100 if (shift < HOST_BITS_PER_WIDE_INT)
5101 value = TREE_INT_CST_LOW (local->val);
5102 else
5103 {
5104 gcc_assert (shift < HOST_BITS_PER_DOUBLE_INT);
5105 value = TREE_INT_CST_HIGH (local->val);
5106 shift -= HOST_BITS_PER_WIDE_INT;
5107 }
5108
5109 /* Get the result. This works only when:
5110 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5111 local->byte |= (((value >> shift)
5112 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5113 << (BITS_PER_UNIT - this_time - next_bit));
5114 }
5115 else
5116 {
5117 /* On little-endian machines,
5118 take first the least significant bits of the value
5119 and pack them starting at the least significant
5120 bits of the bytes. */
5121 shift = next_offset - byte_relative_ebitpos;
5122
5123 /* Don't try to take a bunch of bits that cross
5124 the word boundary in the INTEGER_CST. We can
5125 only select bits from the LOW or HIGH part
5126 not from both. */
5127 if (shift < HOST_BITS_PER_WIDE_INT
5128 && shift + this_time > HOST_BITS_PER_WIDE_INT)
5129 this_time = (HOST_BITS_PER_WIDE_INT - shift);
5130
5131 /* Now get the bits from the appropriate constant word. */
5132 if (shift < HOST_BITS_PER_WIDE_INT)
5133 value = TREE_INT_CST_LOW (local->val);
5134 else
5135 {
5136 gcc_assert (shift < HOST_BITS_PER_DOUBLE_INT);
5137 value = TREE_INT_CST_HIGH (local->val);
5138 shift -= HOST_BITS_PER_WIDE_INT;
5139 }
5140
5141 /* Get the result. This works only when:
5142 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5143 local->byte |= (((value >> shift)
5144 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5145 << next_bit);
5146 }
5147
5148 next_offset += this_time;
5149 local->byte_buffer_in_use = true;
5150 }
5151 }
5152
5153 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5154 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5155 caller output state of relevance in recursive invocations. */
5156
5157 static unsigned HOST_WIDE_INT
5158 output_constructor (tree exp, unsigned HOST_WIDE_INT size,
5159 unsigned int align, oc_outer_state *outer)
5160 {
5161 unsigned HOST_WIDE_INT cnt;
5162 constructor_elt *ce;
5163
5164 oc_local_state local;
5165
5166 /* Setup our local state to communicate with helpers. */
5167 local.exp = exp;
5168 local.type = TREE_TYPE (exp);
5169 local.size = size;
5170 local.align = align;
5171 if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5172 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5173 else
5174 local.min_index = NULL_TREE;
5175
5176 local.total_bytes = 0;
5177 local.byte_buffer_in_use = outer != NULL;
5178 local.byte = outer ? outer->byte : 0;
5179 local.last_relative_index = -1;
5180
5181 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5182
5183 /* As CE goes through the elements of the constant, FIELD goes through the
5184 structure fields if the constant is a structure. If the constant is a
5185 union, we override this by getting the field from the TREE_LIST element.
5186 But the constant could also be an array. Then FIELD is zero.
5187
5188 There is always a maximum of one element in the chain LINK for unions
5189 (even if the initializer in a source program incorrectly contains
5190 more one). */
5191
5192 if (TREE_CODE (local.type) == RECORD_TYPE)
5193 local.field = TYPE_FIELDS (local.type);
5194 else
5195 local.field = NULL_TREE;
5196
5197 for (cnt = 0;
5198 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5199 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5200 {
5201 local.val = ce->value;
5202 local.index = NULL_TREE;
5203
5204 /* The element in a union constructor specifies the proper field
5205 or index. */
5206 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5207 local.field = ce->index;
5208
5209 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5210 local.index = ce->index;
5211
5212 if (local.field && flag_verbose_asm)
5213 fprintf (asm_out_file, "%s %s:\n",
5214 ASM_COMMENT_START,
5215 DECL_NAME (local.field)
5216 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5217 : "<anonymous>");
5218
5219 /* Eliminate the marker that makes a cast not be an lvalue. */
5220 if (local.val != NULL_TREE)
5221 STRIP_NOPS (local.val);
5222
5223 /* Output the current element, using the appropriate helper ... */
5224
5225 /* For an array slice not part of an outer bitfield. */
5226 if (!outer
5227 && local.index != NULL_TREE
5228 && TREE_CODE (local.index) == RANGE_EXPR)
5229 output_constructor_array_range (&local);
5230
5231 /* For a field that is neither a true bitfield nor part of an outer one,
5232 known to be at least byte aligned and multiple-of-bytes long. */
5233 else if (!outer
5234 && (local.field == NULL_TREE
5235 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5236 output_constructor_regular_field (&local);
5237
5238 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5239 supported for scalar fields, so we may need to convert first. */
5240 else
5241 {
5242 if (TREE_CODE (local.val) == REAL_CST)
5243 local.val
5244 = fold_unary (VIEW_CONVERT_EXPR,
5245 build_nonstandard_integer_type
5246 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5247 local.val);
5248 output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5249 }
5250 }
5251
5252 /* If we are not at toplevel, save the pending data for our caller.
5253 Otherwise output the pending data and padding zeros as needed. */
5254 if (outer)
5255 outer->byte = local.byte;
5256 else
5257 {
5258 if (local.byte_buffer_in_use)
5259 {
5260 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5261 local.total_bytes++;
5262 }
5263
5264 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5265 {
5266 assemble_zeros (local.size - local.total_bytes);
5267 local.total_bytes = local.size;
5268 }
5269 }
5270
5271 return local.total_bytes;
5272 }
5273
5274 /* Mark DECL as weak. */
5275
5276 static void
5277 mark_weak (tree decl)
5278 {
5279 DECL_WEAK (decl) = 1;
5280
5281 if (DECL_RTL_SET_P (decl)
5282 && MEM_P (DECL_RTL (decl))
5283 && XEXP (DECL_RTL (decl), 0)
5284 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5285 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5286 }
5287
5288 /* Merge weak status between NEWDECL and OLDDECL. */
5289
5290 void
5291 merge_weak (tree newdecl, tree olddecl)
5292 {
5293 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5294 {
5295 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5296 {
5297 tree *pwd;
5298 /* We put the NEWDECL on the weak_decls list at some point
5299 and OLDDECL as well. Keep just OLDDECL on the list. */
5300 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5301 if (TREE_VALUE (*pwd) == newdecl)
5302 {
5303 *pwd = TREE_CHAIN (*pwd);
5304 break;
5305 }
5306 }
5307 return;
5308 }
5309
5310 if (DECL_WEAK (newdecl))
5311 {
5312 tree wd;
5313
5314 /* NEWDECL is weak, but OLDDECL is not. */
5315
5316 /* If we already output the OLDDECL, we're in trouble; we can't
5317 go back and make it weak. This should never happen in
5318 unit-at-a-time compilation. */
5319 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5320
5321 /* If we've already generated rtl referencing OLDDECL, we may
5322 have done so in a way that will not function properly with
5323 a weak symbol. Again in unit-at-a-time this should be
5324 impossible. */
5325 gcc_assert (!TREE_USED (olddecl)
5326 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5327
5328 if (TARGET_SUPPORTS_WEAK)
5329 {
5330 /* We put the NEWDECL on the weak_decls list at some point.
5331 Replace it with the OLDDECL. */
5332 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5333 if (TREE_VALUE (wd) == newdecl)
5334 {
5335 TREE_VALUE (wd) = olddecl;
5336 break;
5337 }
5338 /* We may not find the entry on the list. If NEWDECL is a
5339 weak alias, then we will have already called
5340 globalize_decl to remove the entry; in that case, we do
5341 not need to do anything. */
5342 }
5343
5344 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5345 mark_weak (olddecl);
5346 }
5347 else
5348 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5349 weak. Just update NEWDECL to indicate that it's weak too. */
5350 mark_weak (newdecl);
5351 }
5352
5353 /* Declare DECL to be a weak symbol. */
5354
5355 void
5356 declare_weak (tree decl)
5357 {
5358 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5359 if (! TREE_PUBLIC (decl))
5360 error ("weak declaration of %q+D must be public", decl);
5361 else if (!TARGET_SUPPORTS_WEAK)
5362 warning (0, "weak declaration of %q+D not supported", decl);
5363
5364 mark_weak (decl);
5365 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5366 DECL_ATTRIBUTES (decl)
5367 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5368 }
5369
5370 static void
5371 weak_finish_1 (tree decl)
5372 {
5373 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5374 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5375 #endif
5376
5377 if (! TREE_USED (decl))
5378 return;
5379
5380 #ifdef ASM_WEAKEN_DECL
5381 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5382 #else
5383 #ifdef ASM_WEAKEN_LABEL
5384 ASM_WEAKEN_LABEL (asm_out_file, name);
5385 #else
5386 #ifdef ASM_OUTPUT_WEAK_ALIAS
5387 {
5388 static bool warn_once = 0;
5389 if (! warn_once)
5390 {
5391 warning (0, "only weak aliases are supported in this configuration");
5392 warn_once = 1;
5393 }
5394 return;
5395 }
5396 #endif
5397 #endif
5398 #endif
5399 }
5400
5401 /* Fiven an assembly name, find the decl it is associated with. */
5402 static tree
5403 find_decl (tree target)
5404 {
5405 symtab_node node = symtab_node_for_asm (target);
5406 if (node)
5407 return node->symbol.decl;
5408 return NULL_TREE;
5409 }
5410
5411 /* This TREE_LIST contains weakref targets. */
5412
5413 static GTY(()) tree weakref_targets;
5414
5415 /* Emit any pending weak declarations. */
5416
5417 void
5418 weak_finish (void)
5419 {
5420 tree t;
5421
5422 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5423 {
5424 tree alias_decl = TREE_PURPOSE (t);
5425 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5426
5427 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5428 /* Remove alias_decl from the weak list, but leave entries for
5429 the target alone. */
5430 target = NULL_TREE;
5431 #ifndef ASM_OUTPUT_WEAKREF
5432 else if (! TREE_SYMBOL_REFERENCED (target))
5433 {
5434 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5435 defined, otherwise we and weak_finish_1 would use
5436 different macros. */
5437 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5438 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5439 # else
5440 tree decl = find_decl (target);
5441
5442 if (! decl)
5443 {
5444 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5445 TREE_CODE (alias_decl), target,
5446 TREE_TYPE (alias_decl));
5447
5448 DECL_EXTERNAL (decl) = 1;
5449 TREE_PUBLIC (decl) = 1;
5450 DECL_ARTIFICIAL (decl) = 1;
5451 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5452 TREE_USED (decl) = 1;
5453 }
5454
5455 weak_finish_1 (decl);
5456 # endif
5457 }
5458 #endif
5459
5460 {
5461 tree *p;
5462 tree t2;
5463
5464 /* Remove the alias and the target from the pending weak list
5465 so that we do not emit any .weak directives for the former,
5466 nor multiple .weak directives for the latter. */
5467 for (p = &weak_decls; (t2 = *p) ; )
5468 {
5469 if (TREE_VALUE (t2) == alias_decl
5470 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5471 *p = TREE_CHAIN (t2);
5472 else
5473 p = &TREE_CHAIN (t2);
5474 }
5475
5476 /* Remove other weakrefs to the same target, to speed things up. */
5477 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5478 {
5479 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5480 *p = TREE_CHAIN (t2);
5481 else
5482 p = &TREE_CHAIN (t2);
5483 }
5484 }
5485 }
5486
5487 for (t = weak_decls; t; t = TREE_CHAIN (t))
5488 {
5489 tree decl = TREE_VALUE (t);
5490
5491 weak_finish_1 (decl);
5492 }
5493 }
5494
5495 /* Emit the assembly bits to indicate that DECL is globally visible. */
5496
5497 static void
5498 globalize_decl (tree decl)
5499 {
5500
5501 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5502 if (DECL_WEAK (decl))
5503 {
5504 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5505 tree *p, t;
5506
5507 #ifdef ASM_WEAKEN_DECL
5508 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5509 #else
5510 ASM_WEAKEN_LABEL (asm_out_file, name);
5511 #endif
5512
5513 /* Remove this function from the pending weak list so that
5514 we do not emit multiple .weak directives for it. */
5515 for (p = &weak_decls; (t = *p) ; )
5516 {
5517 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5518 *p = TREE_CHAIN (t);
5519 else
5520 p = &TREE_CHAIN (t);
5521 }
5522
5523 /* Remove weakrefs to the same target from the pending weakref
5524 list, for the same reason. */
5525 for (p = &weakref_targets; (t = *p) ; )
5526 {
5527 if (DECL_ASSEMBLER_NAME (decl)
5528 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5529 *p = TREE_CHAIN (t);
5530 else
5531 p = &TREE_CHAIN (t);
5532 }
5533
5534 return;
5535 }
5536 #endif
5537
5538 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5539 }
5540
5541 vec<alias_pair, va_gc> *alias_pairs;
5542
5543 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5544 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5545 tree node is DECL to have the value of the tree node TARGET. */
5546
5547 void
5548 do_assemble_alias (tree decl, tree target)
5549 {
5550 /* Emulated TLS had better not get this var. */
5551 gcc_assert (!(!targetm.have_tls
5552 && TREE_CODE (decl) == VAR_DECL
5553 && DECL_THREAD_LOCAL_P (decl)));
5554
5555 if (TREE_ASM_WRITTEN (decl))
5556 return;
5557
5558 /* We must force creation of DECL_RTL for debug info generation, even though
5559 we don't use it here. */
5560 make_decl_rtl (decl);
5561
5562 TREE_ASM_WRITTEN (decl) = 1;
5563 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5564
5565 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5566 {
5567 ultimate_transparent_alias_target (&target);
5568
5569 if (!TREE_SYMBOL_REFERENCED (target))
5570 weakref_targets = tree_cons (decl, target, weakref_targets);
5571
5572 #ifdef ASM_OUTPUT_WEAKREF
5573 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5574 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5575 IDENTIFIER_POINTER (target));
5576 #else
5577 if (!TARGET_SUPPORTS_WEAK)
5578 {
5579 error_at (DECL_SOURCE_LOCATION (decl),
5580 "weakref is not supported in this configuration");
5581 return;
5582 }
5583 #endif
5584 return;
5585 }
5586
5587 #ifdef ASM_OUTPUT_DEF
5588 /* Make name accessible from other files, if appropriate. */
5589
5590 if (TREE_PUBLIC (decl))
5591 {
5592 globalize_decl (decl);
5593 maybe_assemble_visibility (decl);
5594 }
5595 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5596 {
5597 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5598 if (targetm.has_ifunc_p ())
5599 ASM_OUTPUT_TYPE_DIRECTIVE
5600 (asm_out_file, IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5601 IFUNC_ASM_TYPE);
5602 else
5603 #endif
5604 error_at (DECL_SOURCE_LOCATION (decl),
5605 "ifunc is not supported on this target");
5606 }
5607
5608 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5609 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5610 # else
5611 ASM_OUTPUT_DEF (asm_out_file,
5612 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5613 IDENTIFIER_POINTER (target));
5614 # endif
5615 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5616 {
5617 const char *name;
5618 tree *p, t;
5619
5620 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5621 # ifdef ASM_WEAKEN_DECL
5622 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5623 # else
5624 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5625 # endif
5626 /* Remove this function from the pending weak list so that
5627 we do not emit multiple .weak directives for it. */
5628 for (p = &weak_decls; (t = *p) ; )
5629 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5630 *p = TREE_CHAIN (t);
5631 else
5632 p = &TREE_CHAIN (t);
5633
5634 /* Remove weakrefs to the same target from the pending weakref
5635 list, for the same reason. */
5636 for (p = &weakref_targets; (t = *p) ; )
5637 {
5638 if (DECL_ASSEMBLER_NAME (decl)
5639 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5640 *p = TREE_CHAIN (t);
5641 else
5642 p = &TREE_CHAIN (t);
5643 }
5644 }
5645 #endif
5646 }
5647
5648 /* Emit an assembler directive to make the symbol for DECL an alias to
5649 the symbol for TARGET. */
5650
5651 void
5652 assemble_alias (tree decl, tree target)
5653 {
5654 tree target_decl;
5655
5656 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5657 {
5658 tree alias = DECL_ASSEMBLER_NAME (decl);
5659
5660 ultimate_transparent_alias_target (&target);
5661
5662 if (alias == target)
5663 error ("weakref %q+D ultimately targets itself", decl);
5664 if (TREE_PUBLIC (decl))
5665 error ("weakref %q+D must have static linkage", decl);
5666 }
5667 else
5668 {
5669 #if !defined (ASM_OUTPUT_DEF)
5670 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5671 error_at (DECL_SOURCE_LOCATION (decl),
5672 "alias definitions not supported in this configuration");
5673 return;
5674 # else
5675 if (!DECL_WEAK (decl))
5676 {
5677 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5678 error_at (DECL_SOURCE_LOCATION (decl),
5679 "ifunc is not supported in this configuration");
5680 else
5681 error_at (DECL_SOURCE_LOCATION (decl),
5682 "only weak aliases are supported in this configuration");
5683 return;
5684 }
5685 # endif
5686 #endif
5687 }
5688 TREE_USED (decl) = 1;
5689
5690 /* Allow aliases to aliases. */
5691 if (TREE_CODE (decl) == FUNCTION_DECL)
5692 cgraph_get_create_node (decl)->symbol.alias = true;
5693 else
5694 varpool_node_for_decl (decl)->symbol.alias = true;
5695
5696 /* If the target has already been emitted, we don't have to queue the
5697 alias. This saves a tad of memory. */
5698 if (cgraph_global_info_ready)
5699 target_decl = find_decl (target);
5700 else
5701 target_decl= NULL;
5702 if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5703 || cgraph_state >= CGRAPH_STATE_EXPANSION)
5704 do_assemble_alias (decl, target);
5705 else
5706 {
5707 alias_pair p = {decl, target};
5708 vec_safe_push (alias_pairs, p);
5709 }
5710 }
5711
5712 /* Record and output a table of translations from original function
5713 to its transaction aware clone. Note that tm_pure functions are
5714 considered to be their own clone. */
5715
5716 static GTY((if_marked ("tree_map_marked_p"), param_is (struct tree_map)))
5717 htab_t tm_clone_hash;
5718
5719 void
5720 record_tm_clone_pair (tree o, tree n)
5721 {
5722 struct tree_map **slot, *h;
5723
5724 if (tm_clone_hash == NULL)
5725 tm_clone_hash = htab_create_ggc (32, tree_map_hash, tree_map_eq, 0);
5726
5727 h = ggc_alloc_tree_map ();
5728 h->hash = htab_hash_pointer (o);
5729 h->base.from = o;
5730 h->to = n;
5731
5732 slot = (struct tree_map **)
5733 htab_find_slot_with_hash (tm_clone_hash, h, h->hash, INSERT);
5734 *slot = h;
5735 }
5736
5737 tree
5738 get_tm_clone_pair (tree o)
5739 {
5740 if (tm_clone_hash)
5741 {
5742 struct tree_map *h, in;
5743
5744 in.base.from = o;
5745 in.hash = htab_hash_pointer (o);
5746 h = (struct tree_map *) htab_find_with_hash (tm_clone_hash,
5747 &in, in.hash);
5748 if (h)
5749 return h->to;
5750 }
5751 return NULL_TREE;
5752 }
5753
5754 typedef struct tm_alias_pair
5755 {
5756 unsigned int uid;
5757 tree from;
5758 tree to;
5759 } tm_alias_pair;
5760
5761
5762 /* Helper function for finish_tm_clone_pairs. Dump a hash table entry
5763 into a VEC in INFO. */
5764
5765 static int
5766 dump_tm_clone_to_vec (void **slot, void *info)
5767 {
5768 struct tree_map *map = (struct tree_map *) *slot;
5769 vec<tm_alias_pair> *tm_alias_pairs = (vec<tm_alias_pair> *) info;
5770 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
5771 tm_alias_pairs->safe_push (p);
5772 return 1;
5773 }
5774
5775 /* Dump the actual pairs to the .tm_clone_table section. */
5776
5777 static void
5778 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
5779 {
5780 unsigned i;
5781 tm_alias_pair *p;
5782 bool switched = false;
5783
5784 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
5785 {
5786 tree src = p->from;
5787 tree dst = p->to;
5788 struct cgraph_node *src_n = cgraph_get_node (src);
5789 struct cgraph_node *dst_n = cgraph_get_node (dst);
5790
5791 /* The function ipa_tm_create_version() marks the clone as needed if
5792 the original function was needed. But we also mark the clone as
5793 needed if we ever called the clone indirectly through
5794 TM_GETTMCLONE. If neither of these are true, we didn't generate
5795 a clone, and we didn't call it indirectly... no sense keeping it
5796 in the clone table. */
5797 if (!dst_n || !dst_n->symbol.definition)
5798 continue;
5799
5800 /* This covers the case where we have optimized the original
5801 function away, and only access the transactional clone. */
5802 if (!src_n || !src_n->symbol.definition)
5803 continue;
5804
5805 if (!switched)
5806 {
5807 switch_to_section (targetm.asm_out.tm_clone_table_section ());
5808 assemble_align (POINTER_SIZE);
5809 switched = true;
5810 }
5811
5812 assemble_integer (XEXP (DECL_RTL (src), 0),
5813 POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
5814 assemble_integer (XEXP (DECL_RTL (dst), 0),
5815 POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
5816 }
5817 }
5818
5819 /* Provide a default for the tm_clone_table section. */
5820
5821 section *
5822 default_clone_table_section (void)
5823 {
5824 return get_named_section (NULL, ".tm_clone_table", 3);
5825 }
5826
5827 /* Helper comparison function for qsorting by the DECL_UID stored in
5828 alias_pair->emitted_diags. */
5829
5830 static int
5831 tm_alias_pair_cmp (const void *x, const void *y)
5832 {
5833 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
5834 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
5835 if (p1->uid < p2->uid)
5836 return -1;
5837 if (p1->uid > p2->uid)
5838 return 1;
5839 return 0;
5840 }
5841
5842 void
5843 finish_tm_clone_pairs (void)
5844 {
5845 vec<tm_alias_pair> tm_alias_pairs = vNULL;
5846
5847 if (tm_clone_hash == NULL)
5848 return;
5849
5850 /* We need a determenistic order for the .tm_clone_table, otherwise
5851 we will get bootstrap comparison failures, so dump the hash table
5852 to a vector, sort it, and dump the vector. */
5853
5854 /* Dump the hashtable to a vector. */
5855 htab_traverse_noresize (tm_clone_hash, dump_tm_clone_to_vec,
5856 (void *) &tm_alias_pairs);
5857 /* Sort it. */
5858 tm_alias_pairs.qsort (tm_alias_pair_cmp);
5859
5860 /* Dump it. */
5861 dump_tm_clone_pairs (tm_alias_pairs);
5862
5863 htab_delete (tm_clone_hash);
5864 tm_clone_hash = NULL;
5865 tm_alias_pairs.release ();
5866 }
5867
5868
5869 /* Emit an assembler directive to set symbol for DECL visibility to
5870 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
5871
5872 void
5873 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
5874 int vis ATTRIBUTE_UNUSED)
5875 {
5876 #ifdef HAVE_GAS_HIDDEN
5877 static const char * const visibility_types[] = {
5878 NULL, "protected", "hidden", "internal"
5879 };
5880
5881 const char *name, *type;
5882
5883 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5884 type = visibility_types[vis];
5885
5886 fprintf (asm_out_file, "\t.%s\t", type);
5887 assemble_name (asm_out_file, name);
5888 fprintf (asm_out_file, "\n");
5889 #else
5890 if (!DECL_ARTIFICIAL (decl))
5891 warning (OPT_Wattributes, "visibility attribute not supported "
5892 "in this configuration; ignored");
5893 #endif
5894 }
5895
5896 /* A helper function to call assemble_visibility when needed for a decl. */
5897
5898 int
5899 maybe_assemble_visibility (tree decl)
5900 {
5901 enum symbol_visibility vis = DECL_VISIBILITY (decl);
5902
5903 if (vis != VISIBILITY_DEFAULT)
5904 {
5905 targetm.asm_out.assemble_visibility (decl, vis);
5906 return 1;
5907 }
5908 else
5909 return 0;
5910 }
5911
5912 /* Returns 1 if the target configuration supports defining public symbols
5913 so that one of them will be chosen at link time instead of generating a
5914 multiply-defined symbol error, whether through the use of weak symbols or
5915 a target-specific mechanism for having duplicates discarded. */
5916
5917 int
5918 supports_one_only (void)
5919 {
5920 if (SUPPORTS_ONE_ONLY)
5921 return 1;
5922 return TARGET_SUPPORTS_WEAK;
5923 }
5924
5925 /* Set up DECL as a public symbol that can be defined in multiple
5926 translation units without generating a linker error. */
5927
5928 void
5929 make_decl_one_only (tree decl, tree comdat_group)
5930 {
5931 gcc_assert (TREE_CODE (decl) == VAR_DECL
5932 || TREE_CODE (decl) == FUNCTION_DECL);
5933
5934 TREE_PUBLIC (decl) = 1;
5935
5936 if (SUPPORTS_ONE_ONLY)
5937 {
5938 #ifdef MAKE_DECL_ONE_ONLY
5939 MAKE_DECL_ONE_ONLY (decl);
5940 #endif
5941 DECL_COMDAT_GROUP (decl) = comdat_group;
5942 }
5943 else if (TREE_CODE (decl) == VAR_DECL
5944 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node))
5945 DECL_COMMON (decl) = 1;
5946 else
5947 {
5948 gcc_assert (TARGET_SUPPORTS_WEAK);
5949 DECL_WEAK (decl) = 1;
5950 }
5951 }
5952
5953 void
5954 init_varasm_once (void)
5955 {
5956 section_htab = htab_create_ggc (31, section_entry_hash,
5957 section_entry_eq, NULL);
5958 object_block_htab = htab_create_ggc (31, object_block_entry_hash,
5959 object_block_entry_eq, NULL);
5960 const_desc_htab = htab_create_ggc (1009, const_desc_hash,
5961 const_desc_eq, NULL);
5962
5963 const_alias_set = new_alias_set ();
5964 shared_constant_pool = create_constant_pool ();
5965
5966 #ifdef TEXT_SECTION_ASM_OP
5967 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
5968 TEXT_SECTION_ASM_OP);
5969 #endif
5970
5971 #ifdef DATA_SECTION_ASM_OP
5972 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5973 DATA_SECTION_ASM_OP);
5974 #endif
5975
5976 #ifdef SDATA_SECTION_ASM_OP
5977 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5978 SDATA_SECTION_ASM_OP);
5979 #endif
5980
5981 #ifdef READONLY_DATA_SECTION_ASM_OP
5982 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
5983 READONLY_DATA_SECTION_ASM_OP);
5984 #endif
5985
5986 #ifdef CTORS_SECTION_ASM_OP
5987 ctors_section = get_unnamed_section (0, output_section_asm_op,
5988 CTORS_SECTION_ASM_OP);
5989 #endif
5990
5991 #ifdef DTORS_SECTION_ASM_OP
5992 dtors_section = get_unnamed_section (0, output_section_asm_op,
5993 DTORS_SECTION_ASM_OP);
5994 #endif
5995
5996 #ifdef BSS_SECTION_ASM_OP
5997 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5998 output_section_asm_op,
5999 BSS_SECTION_ASM_OP);
6000 #endif
6001
6002 #ifdef SBSS_SECTION_ASM_OP
6003 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6004 output_section_asm_op,
6005 SBSS_SECTION_ASM_OP);
6006 #endif
6007
6008 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6009 | SECTION_COMMON, emit_tls_common);
6010 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6011 | SECTION_COMMON, emit_local);
6012 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6013 | SECTION_COMMON, emit_common);
6014
6015 #if defined ASM_OUTPUT_ALIGNED_BSS
6016 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
6017 emit_bss);
6018 #endif
6019
6020 targetm.asm_out.init_sections ();
6021
6022 if (readonly_data_section == NULL)
6023 readonly_data_section = text_section;
6024
6025 #ifdef ASM_OUTPUT_EXTERNAL
6026 pending_assemble_externals_set = pointer_set_create ();
6027 #endif
6028 }
6029
6030 enum tls_model
6031 decl_default_tls_model (const_tree decl)
6032 {
6033 enum tls_model kind;
6034 bool is_local;
6035
6036 is_local = targetm.binds_local_p (decl);
6037 if (!flag_shlib)
6038 {
6039 if (is_local)
6040 kind = TLS_MODEL_LOCAL_EXEC;
6041 else
6042 kind = TLS_MODEL_INITIAL_EXEC;
6043 }
6044
6045 /* Local dynamic is inefficient when we're not combining the
6046 parts of the address. */
6047 else if (optimize && is_local)
6048 kind = TLS_MODEL_LOCAL_DYNAMIC;
6049 else
6050 kind = TLS_MODEL_GLOBAL_DYNAMIC;
6051 if (kind < flag_tls_default)
6052 kind = flag_tls_default;
6053
6054 return kind;
6055 }
6056
6057 /* Select a set of attributes for section NAME based on the properties
6058 of DECL and whether or not RELOC indicates that DECL's initializer
6059 might contain runtime relocations.
6060
6061 We make the section read-only and executable for a function decl,
6062 read-only for a const data decl, and writable for a non-const data decl. */
6063
6064 unsigned int
6065 default_section_type_flags (tree decl, const char *name, int reloc)
6066 {
6067 unsigned int flags;
6068
6069 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6070 flags = SECTION_CODE;
6071 else if (decl)
6072 {
6073 enum section_category category
6074 = categorize_decl_for_section (decl, reloc);
6075 if (decl_readonly_section_1 (category))
6076 flags = 0;
6077 else if (category == SECCAT_DATA_REL_RO
6078 || category == SECCAT_DATA_REL_RO_LOCAL)
6079 flags = SECTION_WRITE | SECTION_RELRO;
6080 else
6081 flags = SECTION_WRITE;
6082 }
6083 else
6084 {
6085 flags = SECTION_WRITE;
6086 if (strcmp (name, ".data.rel.ro") == 0
6087 || strcmp (name, ".data.rel.ro.local") == 0)
6088 flags |= SECTION_RELRO;
6089 }
6090
6091 if (decl && DECL_P (decl) && DECL_ONE_ONLY (decl))
6092 flags |= SECTION_LINKONCE;
6093
6094 if (strcmp (name, ".vtable_map_vars") == 0)
6095 flags |= SECTION_LINKONCE;
6096
6097 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6098 flags |= SECTION_TLS | SECTION_WRITE;
6099
6100 if (strcmp (name, ".bss") == 0
6101 || strncmp (name, ".bss.", 5) == 0
6102 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6103 || strcmp (name, ".sbss") == 0
6104 || strncmp (name, ".sbss.", 6) == 0
6105 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6106 flags |= SECTION_BSS;
6107
6108 if (strcmp (name, ".tdata") == 0
6109 || strncmp (name, ".tdata.", 7) == 0
6110 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6111 flags |= SECTION_TLS;
6112
6113 if (strcmp (name, ".tbss") == 0
6114 || strncmp (name, ".tbss.", 6) == 0
6115 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6116 flags |= SECTION_TLS | SECTION_BSS;
6117
6118 /* These three sections have special ELF types. They are neither
6119 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
6120 want to print a section type (@progbits or @nobits). If someone
6121 is silly enough to emit code or TLS variables to one of these
6122 sections, then don't handle them specially. */
6123 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6124 && (strcmp (name, ".init_array") == 0
6125 || strcmp (name, ".fini_array") == 0
6126 || strcmp (name, ".preinit_array") == 0))
6127 flags |= SECTION_NOTYPE;
6128
6129 return flags;
6130 }
6131
6132 /* Return true if the target supports some form of global BSS,
6133 either through bss_noswitch_section, or by selecting a BSS
6134 section in TARGET_ASM_SELECT_SECTION. */
6135
6136 bool
6137 have_global_bss_p (void)
6138 {
6139 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6140 }
6141
6142 /* Output assembly to switch to section NAME with attribute FLAGS.
6143 Four variants for common object file formats. */
6144
6145 void
6146 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6147 unsigned int flags ATTRIBUTE_UNUSED,
6148 tree decl ATTRIBUTE_UNUSED)
6149 {
6150 /* Some object formats don't support named sections at all. The
6151 front-end should already have flagged this as an error. */
6152 gcc_unreachable ();
6153 }
6154
6155 #ifndef TLS_SECTION_ASM_FLAG
6156 #define TLS_SECTION_ASM_FLAG 'T'
6157 #endif
6158
6159 void
6160 default_elf_asm_named_section (const char *name, unsigned int flags,
6161 tree decl ATTRIBUTE_UNUSED)
6162 {
6163 char flagchars[10], *f = flagchars;
6164
6165 /* If we have already declared this section, we can use an
6166 abbreviated form to switch back to it -- unless this section is
6167 part of a COMDAT groups, in which case GAS requires the full
6168 declaration every time. */
6169 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6170 && (flags & SECTION_DECLARED))
6171 {
6172 fprintf (asm_out_file, "\t.section\t%s\n", name);
6173 return;
6174 }
6175
6176 if (!(flags & SECTION_DEBUG))
6177 *f++ = 'a';
6178 if (flags & SECTION_EXCLUDE)
6179 *f++ = 'e';
6180 if (flags & SECTION_WRITE)
6181 *f++ = 'w';
6182 if (flags & SECTION_CODE)
6183 *f++ = 'x';
6184 if (flags & SECTION_SMALL)
6185 *f++ = 's';
6186 if (flags & SECTION_MERGE)
6187 *f++ = 'M';
6188 if (flags & SECTION_STRINGS)
6189 *f++ = 'S';
6190 if (flags & SECTION_TLS)
6191 *f++ = TLS_SECTION_ASM_FLAG;
6192 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6193 *f++ = 'G';
6194 *f = '\0';
6195
6196 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6197
6198 if (!(flags & SECTION_NOTYPE))
6199 {
6200 const char *type;
6201 const char *format;
6202
6203 if (flags & SECTION_BSS)
6204 type = "nobits";
6205 else
6206 type = "progbits";
6207
6208 format = ",@%s";
6209 /* On platforms that use "@" as the assembly comment character,
6210 use "%" instead. */
6211 if (strcmp (ASM_COMMENT_START, "@") == 0)
6212 format = ",%%%s";
6213 fprintf (asm_out_file, format, type);
6214
6215 if (flags & SECTION_ENTSIZE)
6216 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6217 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6218 {
6219 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6220 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6221 else
6222 fprintf (asm_out_file, ",%s,comdat",
6223 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6224 }
6225 }
6226
6227 putc ('\n', asm_out_file);
6228 }
6229
6230 void
6231 default_coff_asm_named_section (const char *name, unsigned int flags,
6232 tree decl ATTRIBUTE_UNUSED)
6233 {
6234 char flagchars[8], *f = flagchars;
6235
6236 if (flags & SECTION_WRITE)
6237 *f++ = 'w';
6238 if (flags & SECTION_CODE)
6239 *f++ = 'x';
6240 *f = '\0';
6241
6242 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6243 }
6244
6245 void
6246 default_pe_asm_named_section (const char *name, unsigned int flags,
6247 tree decl)
6248 {
6249 default_coff_asm_named_section (name, flags, decl);
6250
6251 if (flags & SECTION_LINKONCE)
6252 {
6253 /* Functions may have been compiled at various levels of
6254 optimization so we can't use `same_size' here.
6255 Instead, have the linker pick one. */
6256 fprintf (asm_out_file, "\t.linkonce %s\n",
6257 (flags & SECTION_CODE ? "discard" : "same_size"));
6258 }
6259 }
6260 \f
6261 /* The lame default section selector. */
6262
6263 section *
6264 default_select_section (tree decl, int reloc,
6265 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6266 {
6267 if (DECL_P (decl))
6268 {
6269 if (decl_readonly_section (decl, reloc))
6270 return readonly_data_section;
6271 }
6272 else if (TREE_CODE (decl) == CONSTRUCTOR)
6273 {
6274 if (! ((flag_pic && reloc)
6275 || !TREE_READONLY (decl)
6276 || TREE_SIDE_EFFECTS (decl)
6277 || !TREE_CONSTANT (decl)))
6278 return readonly_data_section;
6279 }
6280 else if (TREE_CODE (decl) == STRING_CST)
6281 return readonly_data_section;
6282 else if (! (flag_pic && reloc))
6283 return readonly_data_section;
6284
6285 return data_section;
6286 }
6287
6288 enum section_category
6289 categorize_decl_for_section (const_tree decl, int reloc)
6290 {
6291 enum section_category ret;
6292
6293 if (TREE_CODE (decl) == FUNCTION_DECL)
6294 return SECCAT_TEXT;
6295 else if (TREE_CODE (decl) == STRING_CST)
6296 {
6297 if (flag_mudflap
6298 || ((flag_sanitize & SANITIZE_ADDRESS)
6299 && asan_protect_global (CONST_CAST_TREE (decl))))
6300 /* or !flag_merge_constants */
6301 return SECCAT_RODATA;
6302 else
6303 return SECCAT_RODATA_MERGE_STR;
6304 }
6305 else if (TREE_CODE (decl) == VAR_DECL)
6306 {
6307 if (bss_initializer_p (decl))
6308 ret = SECCAT_BSS;
6309 else if (! TREE_READONLY (decl)
6310 || TREE_SIDE_EFFECTS (decl)
6311 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
6312 {
6313 /* Here the reloc_rw_mask is not testing whether the section should
6314 be read-only or not, but whether the dynamic link will have to
6315 do something. If so, we wish to segregate the data in order to
6316 minimize cache misses inside the dynamic linker. */
6317 if (reloc & targetm.asm_out.reloc_rw_mask ())
6318 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6319 else
6320 ret = SECCAT_DATA;
6321 }
6322 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6323 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6324 else if (reloc || flag_merge_constants < 2 || flag_mudflap
6325 || ((flag_sanitize & SANITIZE_ADDRESS)
6326 && asan_protect_global (CONST_CAST_TREE (decl))))
6327 /* C and C++ don't allow different variables to share the same
6328 location. -fmerge-all-constants allows even that (at the
6329 expense of not conforming). */
6330 ret = SECCAT_RODATA;
6331 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6332 ret = SECCAT_RODATA_MERGE_STR_INIT;
6333 else
6334 ret = SECCAT_RODATA_MERGE_CONST;
6335 }
6336 else if (TREE_CODE (decl) == CONSTRUCTOR)
6337 {
6338 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6339 || TREE_SIDE_EFFECTS (decl)
6340 || ! TREE_CONSTANT (decl))
6341 ret = SECCAT_DATA;
6342 else
6343 ret = SECCAT_RODATA;
6344 }
6345 else
6346 ret = SECCAT_RODATA;
6347
6348 /* There are no read-only thread-local sections. */
6349 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6350 {
6351 /* Note that this would be *just* SECCAT_BSS, except that there's
6352 no concept of a read-only thread-local-data section. */
6353 if (ret == SECCAT_BSS
6354 || (flag_zero_initialized_in_bss
6355 && initializer_zerop (DECL_INITIAL (decl))))
6356 ret = SECCAT_TBSS;
6357 else
6358 ret = SECCAT_TDATA;
6359 }
6360
6361 /* If the target uses small data sections, select it. */
6362 else if (targetm.in_small_data_p (decl))
6363 {
6364 if (ret == SECCAT_BSS)
6365 ret = SECCAT_SBSS;
6366 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6367 ret = SECCAT_SRODATA;
6368 else
6369 ret = SECCAT_SDATA;
6370 }
6371
6372 return ret;
6373 }
6374
6375 static bool
6376 decl_readonly_section_1 (enum section_category category)
6377 {
6378 switch (category)
6379 {
6380 case SECCAT_RODATA:
6381 case SECCAT_RODATA_MERGE_STR:
6382 case SECCAT_RODATA_MERGE_STR_INIT:
6383 case SECCAT_RODATA_MERGE_CONST:
6384 case SECCAT_SRODATA:
6385 return true;
6386 default:
6387 return false;
6388 }
6389 }
6390
6391 bool
6392 decl_readonly_section (const_tree decl, int reloc)
6393 {
6394 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6395 }
6396
6397 /* Select a section based on the above categorization. */
6398
6399 section *
6400 default_elf_select_section (tree decl, int reloc,
6401 unsigned HOST_WIDE_INT align)
6402 {
6403 const char *sname;
6404 switch (categorize_decl_for_section (decl, reloc))
6405 {
6406 case SECCAT_TEXT:
6407 /* We're not supposed to be called on FUNCTION_DECLs. */
6408 gcc_unreachable ();
6409 case SECCAT_RODATA:
6410 return readonly_data_section;
6411 case SECCAT_RODATA_MERGE_STR:
6412 return mergeable_string_section (decl, align, 0);
6413 case SECCAT_RODATA_MERGE_STR_INIT:
6414 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6415 case SECCAT_RODATA_MERGE_CONST:
6416 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6417 case SECCAT_SRODATA:
6418 sname = ".sdata2";
6419 break;
6420 case SECCAT_DATA:
6421 return data_section;
6422 case SECCAT_DATA_REL:
6423 sname = ".data.rel";
6424 break;
6425 case SECCAT_DATA_REL_LOCAL:
6426 sname = ".data.rel.local";
6427 break;
6428 case SECCAT_DATA_REL_RO:
6429 sname = ".data.rel.ro";
6430 break;
6431 case SECCAT_DATA_REL_RO_LOCAL:
6432 sname = ".data.rel.ro.local";
6433 break;
6434 case SECCAT_SDATA:
6435 sname = ".sdata";
6436 break;
6437 case SECCAT_TDATA:
6438 sname = ".tdata";
6439 break;
6440 case SECCAT_BSS:
6441 if (bss_section)
6442 return bss_section;
6443 sname = ".bss";
6444 break;
6445 case SECCAT_SBSS:
6446 sname = ".sbss";
6447 break;
6448 case SECCAT_TBSS:
6449 sname = ".tbss";
6450 break;
6451 default:
6452 gcc_unreachable ();
6453 }
6454
6455 return get_named_section (decl, sname, reloc);
6456 }
6457
6458 /* Construct a unique section name based on the decl name and the
6459 categorization performed above. */
6460
6461 void
6462 default_unique_section (tree decl, int reloc)
6463 {
6464 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6465 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6466 const char *prefix, *name, *linkonce;
6467 char *string;
6468
6469 switch (categorize_decl_for_section (decl, reloc))
6470 {
6471 case SECCAT_TEXT:
6472 prefix = one_only ? ".t" : ".text";
6473 break;
6474 case SECCAT_RODATA:
6475 case SECCAT_RODATA_MERGE_STR:
6476 case SECCAT_RODATA_MERGE_STR_INIT:
6477 case SECCAT_RODATA_MERGE_CONST:
6478 prefix = one_only ? ".r" : ".rodata";
6479 break;
6480 case SECCAT_SRODATA:
6481 prefix = one_only ? ".s2" : ".sdata2";
6482 break;
6483 case SECCAT_DATA:
6484 prefix = one_only ? ".d" : ".data";
6485 break;
6486 case SECCAT_DATA_REL:
6487 prefix = one_only ? ".d.rel" : ".data.rel";
6488 break;
6489 case SECCAT_DATA_REL_LOCAL:
6490 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6491 break;
6492 case SECCAT_DATA_REL_RO:
6493 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6494 break;
6495 case SECCAT_DATA_REL_RO_LOCAL:
6496 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6497 break;
6498 case SECCAT_SDATA:
6499 prefix = one_only ? ".s" : ".sdata";
6500 break;
6501 case SECCAT_BSS:
6502 prefix = one_only ? ".b" : ".bss";
6503 break;
6504 case SECCAT_SBSS:
6505 prefix = one_only ? ".sb" : ".sbss";
6506 break;
6507 case SECCAT_TDATA:
6508 prefix = one_only ? ".td" : ".tdata";
6509 break;
6510 case SECCAT_TBSS:
6511 prefix = one_only ? ".tb" : ".tbss";
6512 break;
6513 default:
6514 gcc_unreachable ();
6515 }
6516
6517 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
6518 name = targetm.strip_name_encoding (name);
6519
6520 /* If we're using one_only, then there needs to be a .gnu.linkonce
6521 prefix to the section name. */
6522 linkonce = one_only ? ".gnu.linkonce" : "";
6523
6524 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6525
6526 DECL_SECTION_NAME (decl) = build_string (strlen (string), string);
6527 }
6528
6529 /* Like compute_reloc_for_constant, except for an RTX. The return value
6530 is a mask for which bit 1 indicates a global relocation, and bit 0
6531 indicates a local relocation. */
6532
6533 static int
6534 compute_reloc_for_rtx_1 (rtx *xp, void *data)
6535 {
6536 int *preloc = (int *) data;
6537 rtx x = *xp;
6538
6539 switch (GET_CODE (x))
6540 {
6541 case SYMBOL_REF:
6542 *preloc |= SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6543 break;
6544 case LABEL_REF:
6545 *preloc |= 1;
6546 break;
6547 default:
6548 break;
6549 }
6550
6551 return 0;
6552 }
6553
6554 static int
6555 compute_reloc_for_rtx (rtx x)
6556 {
6557 int reloc;
6558
6559 switch (GET_CODE (x))
6560 {
6561 case CONST:
6562 case SYMBOL_REF:
6563 case LABEL_REF:
6564 reloc = 0;
6565 for_each_rtx (&x, compute_reloc_for_rtx_1, &reloc);
6566 return reloc;
6567
6568 default:
6569 return 0;
6570 }
6571 }
6572
6573 section *
6574 default_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
6575 rtx x,
6576 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6577 {
6578 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6579 return data_section;
6580 else
6581 return readonly_data_section;
6582 }
6583
6584 section *
6585 default_elf_select_rtx_section (enum machine_mode mode, rtx x,
6586 unsigned HOST_WIDE_INT align)
6587 {
6588 int reloc = compute_reloc_for_rtx (x);
6589
6590 /* ??? Handle small data here somehow. */
6591
6592 if (reloc & targetm.asm_out.reloc_rw_mask ())
6593 {
6594 if (reloc == 1)
6595 return get_named_section (NULL, ".data.rel.ro.local", 1);
6596 else
6597 return get_named_section (NULL, ".data.rel.ro", 3);
6598 }
6599
6600 return mergeable_constant_section (mode, align, 0);
6601 }
6602
6603 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6604
6605 void
6606 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6607 {
6608 rtx symbol;
6609 int flags;
6610
6611 /* Careful not to prod global register variables. */
6612 if (!MEM_P (rtl))
6613 return;
6614 symbol = XEXP (rtl, 0);
6615 if (GET_CODE (symbol) != SYMBOL_REF)
6616 return;
6617
6618 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6619 if (TREE_CODE (decl) == FUNCTION_DECL)
6620 flags |= SYMBOL_FLAG_FUNCTION;
6621 if (targetm.binds_local_p (decl))
6622 flags |= SYMBOL_FLAG_LOCAL;
6623 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6624 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6625 else if (targetm.in_small_data_p (decl))
6626 flags |= SYMBOL_FLAG_SMALL;
6627 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6628 being PUBLIC, the thing *must* be defined in this translation unit.
6629 Prevent this buglet from being propagated into rtl code as well. */
6630 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6631 flags |= SYMBOL_FLAG_EXTERNAL;
6632
6633 SYMBOL_REF_FLAGS (symbol) = flags;
6634 }
6635
6636 /* By default, we do nothing for encode_section_info, so we need not
6637 do anything but discard the '*' marker. */
6638
6639 const char *
6640 default_strip_name_encoding (const char *str)
6641 {
6642 return str + (*str == '*');
6643 }
6644
6645 #ifdef ASM_OUTPUT_DEF
6646 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6647 anchor relative to ".", the current section position. */
6648
6649 void
6650 default_asm_output_anchor (rtx symbol)
6651 {
6652 char buffer[100];
6653
6654 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6655 SYMBOL_REF_BLOCK_OFFSET (symbol));
6656 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6657 }
6658 #endif
6659
6660 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6661
6662 bool
6663 default_use_anchors_for_symbol_p (const_rtx symbol)
6664 {
6665 section *sect;
6666 tree decl;
6667
6668 /* Don't use anchors for mergeable sections. The linker might move
6669 the objects around. */
6670 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6671 if (sect->common.flags & SECTION_MERGE)
6672 return false;
6673
6674 /* Don't use anchors for small data sections. The small data register
6675 acts as an anchor for such sections. */
6676 if (sect->common.flags & SECTION_SMALL)
6677 return false;
6678
6679 decl = SYMBOL_REF_DECL (symbol);
6680 if (decl && DECL_P (decl))
6681 {
6682 /* Don't use section anchors for decls that might be defined or
6683 usurped by other modules. */
6684 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6685 return false;
6686
6687 /* Don't use section anchors for decls that will be placed in a
6688 small data section. */
6689 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6690 one above. The problem is that we only use SECTION_SMALL for
6691 sections that should be marked as small in the section directive. */
6692 if (targetm.in_small_data_p (decl))
6693 return false;
6694 }
6695 return true;
6696 }
6697
6698 /* Return true when RESOLUTION indicate that symbol will be bound to the
6699 definition provided by current .o file. */
6700
6701 static bool
6702 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
6703 {
6704 return (resolution == LDPR_PREVAILING_DEF
6705 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6706 || resolution == LDPR_PREVAILING_DEF_IRONLY);
6707 }
6708
6709 /* Return true when RESOLUTION indicate that symbol will be bound locally
6710 within current executable or DSO. */
6711
6712 static bool
6713 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
6714 {
6715 return (resolution == LDPR_PREVAILING_DEF
6716 || resolution == LDPR_PREVAILING_DEF_IRONLY
6717 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6718 || resolution == LDPR_PREEMPTED_REG
6719 || resolution == LDPR_PREEMPTED_IR
6720 || resolution == LDPR_RESOLVED_IR
6721 || resolution == LDPR_RESOLVED_EXEC);
6722 }
6723
6724 /* Assume ELF-ish defaults, since that's pretty much the most liberal
6725 wrt cross-module name binding. */
6726
6727 bool
6728 default_binds_local_p (const_tree exp)
6729 {
6730 return default_binds_local_p_1 (exp, flag_shlib);
6731 }
6732
6733 bool
6734 default_binds_local_p_1 (const_tree exp, int shlib)
6735 {
6736 bool local_p;
6737 bool resolved_locally = false;
6738 bool resolved_to_local_def = false;
6739
6740 /* With resolution file in hands, take look into resolutions.
6741 We can't just return true for resolved_locally symbols,
6742 because dynamic linking might overwrite symbols
6743 in shared libraries. */
6744 if (TREE_CODE (exp) == VAR_DECL && TREE_PUBLIC (exp)
6745 && (TREE_STATIC (exp) || DECL_EXTERNAL (exp)))
6746 {
6747 struct varpool_node *vnode = varpool_get_node (exp);
6748 if (vnode && resolution_local_p (vnode->symbol.resolution))
6749 resolved_locally = true;
6750 if (vnode
6751 && resolution_to_local_definition_p (vnode->symbol.resolution))
6752 resolved_to_local_def = true;
6753 }
6754 else if (TREE_CODE (exp) == FUNCTION_DECL && TREE_PUBLIC (exp))
6755 {
6756 struct cgraph_node *node = cgraph_get_node (exp);
6757 if (node
6758 && resolution_local_p (node->symbol.resolution))
6759 resolved_locally = true;
6760 if (node
6761 && resolution_to_local_definition_p (node->symbol.resolution))
6762 resolved_to_local_def = true;
6763 }
6764
6765 /* A non-decl is an entry in the constant pool. */
6766 if (!DECL_P (exp))
6767 local_p = true;
6768 /* Weakrefs may not bind locally, even though the weakref itself is always
6769 static and therefore local. Similarly, the resolver for ifunc functions
6770 might resolve to a non-local function.
6771 FIXME: We can resolve the weakref case more curefuly by looking at the
6772 weakref alias. */
6773 else if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
6774 || (TREE_CODE (exp) == FUNCTION_DECL
6775 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
6776 local_p = false;
6777 /* Static variables are always local. */
6778 else if (! TREE_PUBLIC (exp))
6779 local_p = true;
6780 /* A variable is local if the user has said explicitly that it will
6781 be. */
6782 else if ((DECL_VISIBILITY_SPECIFIED (exp)
6783 || resolved_to_local_def)
6784 && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6785 local_p = true;
6786 /* Variables defined outside this object might not be local. */
6787 else if (DECL_EXTERNAL (exp) && !resolved_locally)
6788 local_p = false;
6789 /* If defined in this object and visibility is not default, must be
6790 local. */
6791 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6792 local_p = true;
6793 /* Default visibility weak data can be overridden by a strong symbol
6794 in another module and so are not local. */
6795 else if (DECL_WEAK (exp)
6796 && !resolved_locally)
6797 local_p = false;
6798 /* If PIC, then assume that any global name can be overridden by
6799 symbols resolved from other modules. */
6800 else if (shlib)
6801 local_p = false;
6802 /* Uninitialized COMMON variable may be unified with symbols
6803 resolved from other modules. */
6804 else if (DECL_COMMON (exp)
6805 && !resolved_locally
6806 && (DECL_INITIAL (exp) == NULL
6807 || DECL_INITIAL (exp) == error_mark_node))
6808 local_p = false;
6809 /* Otherwise we're left with initialized (or non-common) global data
6810 which is of necessity defined locally. */
6811 else
6812 local_p = true;
6813
6814 return local_p;
6815 }
6816
6817 /* Return true when references to DECL must bind to current definition in
6818 final executable.
6819
6820 The condition is usually equivalent to whether the function binds to the
6821 current module (shared library or executable), that is to binds_local_p.
6822 We use this fact to avoid need for another target hook and implement
6823 the logic using binds_local_p and just special cases where
6824 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
6825 the weak definitions (that can be overwritten at linktime by other
6826 definition from different object file) and when resolution info is available
6827 we simply use the knowledge passed to us by linker plugin. */
6828 bool
6829 decl_binds_to_current_def_p (tree decl)
6830 {
6831 gcc_assert (DECL_P (decl));
6832 if (!targetm.binds_local_p (decl))
6833 return false;
6834 if (!TREE_PUBLIC (decl))
6835 return true;
6836 /* When resolution is available, just use it. */
6837 if (TREE_CODE (decl) == VAR_DECL
6838 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl)))
6839 {
6840 struct varpool_node *vnode = varpool_get_node (decl);
6841 if (vnode
6842 && vnode->symbol.resolution != LDPR_UNKNOWN)
6843 return resolution_to_local_definition_p (vnode->symbol.resolution);
6844 }
6845 else if (TREE_CODE (decl) == FUNCTION_DECL)
6846 {
6847 struct cgraph_node *node = cgraph_get_node (decl);
6848 if (node
6849 && node->symbol.resolution != LDPR_UNKNOWN)
6850 return resolution_to_local_definition_p (node->symbol.resolution);
6851 }
6852 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
6853 binds locally but still can be overwritten), DECL_COMMON (can be merged
6854 with a non-common definition somewhere in the same module) or
6855 DECL_EXTERNAL.
6856 This rely on fact that binds_local_p behave as decl_replaceable_p
6857 for all other declaration types. */
6858 if (DECL_WEAK (decl))
6859 return false;
6860 if (DECL_COMMON (decl)
6861 && (DECL_INITIAL (decl) == NULL
6862 || DECL_INITIAL (decl) == error_mark_node))
6863 return false;
6864 if (DECL_EXTERNAL (decl))
6865 return false;
6866 return true;
6867 }
6868
6869 /* A replaceable function or variable is one which may be replaced
6870 at link-time with an entirely different definition, provided that the
6871 replacement has the same type. For example, functions declared
6872 with __attribute__((weak)) on most systems are replaceable.
6873
6874 COMDAT functions are not replaceable, since all definitions of the
6875 function must be equivalent. It is important that COMDAT functions
6876 not be treated as replaceable so that use of C++ template
6877 instantiations is not penalized. */
6878
6879 bool
6880 decl_replaceable_p (tree decl)
6881 {
6882 gcc_assert (DECL_P (decl));
6883 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
6884 return false;
6885 return !decl_binds_to_current_def_p (decl);
6886 }
6887
6888 /* Default function to output code that will globalize a label. A
6889 target must define GLOBAL_ASM_OP or provide its own function to
6890 globalize a label. */
6891 #ifdef GLOBAL_ASM_OP
6892 void
6893 default_globalize_label (FILE * stream, const char *name)
6894 {
6895 fputs (GLOBAL_ASM_OP, stream);
6896 assemble_name (stream, name);
6897 putc ('\n', stream);
6898 }
6899 #endif /* GLOBAL_ASM_OP */
6900
6901 /* Default function to output code that will globalize a declaration. */
6902 void
6903 default_globalize_decl_name (FILE * stream, tree decl)
6904 {
6905 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
6906 targetm.asm_out.globalize_label (stream, name);
6907 }
6908
6909 /* Default function to output a label for unwind information. The
6910 default is to do nothing. A target that needs nonlocal labels for
6911 unwind information must provide its own function to do this. */
6912 void
6913 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
6914 tree decl ATTRIBUTE_UNUSED,
6915 int for_eh ATTRIBUTE_UNUSED,
6916 int empty ATTRIBUTE_UNUSED)
6917 {
6918 }
6919
6920 /* Default function to output a label to divide up the exception table.
6921 The default is to do nothing. A target that needs/wants to divide
6922 up the table must provide it's own function to do this. */
6923 void
6924 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
6925 {
6926 }
6927
6928 /* This is how to output an internal numbered label where PREFIX is
6929 the class of label and LABELNO is the number within the class. */
6930
6931 void
6932 default_generate_internal_label (char *buf, const char *prefix,
6933 unsigned long labelno)
6934 {
6935 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6936 }
6937
6938 /* This is how to output an internal numbered label where PREFIX is
6939 the class of label and LABELNO is the number within the class. */
6940
6941 void
6942 default_internal_label (FILE *stream, const char *prefix,
6943 unsigned long labelno)
6944 {
6945 char *const buf = (char *) alloca (40 + strlen (prefix));
6946 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6947 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
6948 }
6949
6950
6951 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
6952
6953 void
6954 default_asm_declare_constant_name (FILE *file, const char *name,
6955 const_tree exp ATTRIBUTE_UNUSED,
6956 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
6957 {
6958 assemble_label (file, name);
6959 }
6960
6961 /* This is the default behavior at the beginning of a file. It's
6962 controlled by two other target-hook toggles. */
6963 void
6964 default_file_start (void)
6965 {
6966 if (targetm.asm_file_start_app_off
6967 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
6968 fputs (ASM_APP_OFF, asm_out_file);
6969
6970 if (targetm.asm_file_start_file_directive)
6971 output_file_directive (asm_out_file, main_input_filename);
6972 }
6973
6974 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
6975 which emits a special section directive used to indicate whether or
6976 not this object file needs an executable stack. This is primarily
6977 a GNU extension to ELF but could be used on other targets. */
6978
6979 int trampolines_created;
6980
6981 void
6982 file_end_indicate_exec_stack (void)
6983 {
6984 unsigned int flags = SECTION_DEBUG;
6985 if (trampolines_created)
6986 flags |= SECTION_CODE;
6987
6988 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
6989 }
6990
6991 /* Emit a special section directive to indicate that this object file
6992 was compiled with -fsplit-stack. This is used to let the linker
6993 detect calls between split-stack code and non-split-stack code, so
6994 that it can modify the split-stack code to allocate a sufficiently
6995 large stack. We emit another special section if there are any
6996 functions in this file which have the no_split_stack attribute, to
6997 prevent the linker from warning about being unable to convert the
6998 functions if they call non-split-stack code. */
6999
7000 void
7001 file_end_indicate_split_stack (void)
7002 {
7003 if (flag_split_stack)
7004 {
7005 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
7006 NULL));
7007 if (saw_no_split_stack)
7008 switch_to_section (get_section (".note.GNU-no-split-stack",
7009 SECTION_DEBUG, NULL));
7010 }
7011 }
7012
7013 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
7014 a get_unnamed_section callback. */
7015
7016 void
7017 output_section_asm_op (const void *directive)
7018 {
7019 fprintf (asm_out_file, "%s\n", (const char *) directive);
7020 }
7021
7022 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
7023 the current section is NEW_SECTION. */
7024
7025 void
7026 switch_to_section (section *new_section)
7027 {
7028 if (in_section == new_section)
7029 return;
7030
7031 if (new_section->common.flags & SECTION_FORGET)
7032 in_section = NULL;
7033 else
7034 in_section = new_section;
7035
7036 switch (SECTION_STYLE (new_section))
7037 {
7038 case SECTION_NAMED:
7039 targetm.asm_out.named_section (new_section->named.name,
7040 new_section->named.common.flags,
7041 new_section->named.decl);
7042 break;
7043
7044 case SECTION_UNNAMED:
7045 new_section->unnamed.callback (new_section->unnamed.data);
7046 break;
7047
7048 case SECTION_NOSWITCH:
7049 gcc_unreachable ();
7050 break;
7051 }
7052
7053 new_section->common.flags |= SECTION_DECLARED;
7054 }
7055
7056 /* If block symbol SYMBOL has not yet been assigned an offset, place
7057 it at the end of its block. */
7058
7059 void
7060 place_block_symbol (rtx symbol)
7061 {
7062 unsigned HOST_WIDE_INT size, mask, offset;
7063 struct constant_descriptor_rtx *desc;
7064 unsigned int alignment;
7065 struct object_block *block;
7066 tree decl;
7067
7068 gcc_assert (SYMBOL_REF_BLOCK (symbol));
7069 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7070 return;
7071
7072 /* Work out the symbol's size and alignment. */
7073 if (CONSTANT_POOL_ADDRESS_P (symbol))
7074 {
7075 desc = SYMBOL_REF_CONSTANT (symbol);
7076 alignment = desc->align;
7077 size = GET_MODE_SIZE (desc->mode);
7078 }
7079 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7080 {
7081 decl = SYMBOL_REF_DECL (symbol);
7082 alignment = DECL_ALIGN (decl);
7083 size = get_constant_size (DECL_INITIAL (decl));
7084 if ((flag_sanitize & SANITIZE_ADDRESS)
7085 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7086 && asan_protect_global (DECL_INITIAL (decl)))
7087 size += asan_red_zone_size (size);
7088 }
7089 else
7090 {
7091 decl = SYMBOL_REF_DECL (symbol);
7092 alignment = get_variable_align (decl);
7093 size = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
7094 if ((flag_sanitize & SANITIZE_ADDRESS)
7095 && asan_protect_global (decl))
7096 {
7097 size += asan_red_zone_size (size);
7098 alignment = MAX (alignment,
7099 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7100 }
7101 }
7102
7103 /* Calculate the object's offset from the start of the block. */
7104 block = SYMBOL_REF_BLOCK (symbol);
7105 mask = alignment / BITS_PER_UNIT - 1;
7106 offset = (block->size + mask) & ~mask;
7107 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7108
7109 /* Record the block's new alignment and size. */
7110 block->alignment = MAX (block->alignment, alignment);
7111 block->size = offset + size;
7112
7113 vec_safe_push (block->objects, symbol);
7114 }
7115
7116 /* Return the anchor that should be used to address byte offset OFFSET
7117 from the first object in BLOCK. MODEL is the TLS model used
7118 to access it. */
7119
7120 rtx
7121 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7122 enum tls_model model)
7123 {
7124 char label[100];
7125 unsigned int begin, middle, end;
7126 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7127 rtx anchor;
7128
7129 /* Work out the anchor's offset. Use an offset of 0 for the first
7130 anchor so that we don't pessimize the case where we take the address
7131 of a variable at the beginning of the block. This is particularly
7132 useful when a block has only one variable assigned to it.
7133
7134 We try to place anchors RANGE bytes apart, so there can then be
7135 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7136 a ptr_mode offset. With some target settings, the lowest such
7137 anchor might be out of range for the lowest ptr_mode offset;
7138 likewise the highest anchor for the highest offset. Use anchors
7139 at the extreme ends of the ptr_mode range in such cases.
7140
7141 All arithmetic uses unsigned integers in order to avoid
7142 signed overflow. */
7143 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7144 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7145 range = max_offset - min_offset + 1;
7146 if (range == 0)
7147 offset = 0;
7148 else
7149 {
7150 bias = 1 << (GET_MODE_BITSIZE (ptr_mode) - 1);
7151 if (offset < 0)
7152 {
7153 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7154 delta -= delta % range;
7155 if (delta > bias)
7156 delta = bias;
7157 offset = (HOST_WIDE_INT) (-delta);
7158 }
7159 else
7160 {
7161 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7162 delta -= delta % range;
7163 if (delta > bias - 1)
7164 delta = bias - 1;
7165 offset = (HOST_WIDE_INT) delta;
7166 }
7167 }
7168
7169 /* Do a binary search to see if there's already an anchor we can use.
7170 Set BEGIN to the new anchor's index if not. */
7171 begin = 0;
7172 end = vec_safe_length (block->anchors);
7173 while (begin != end)
7174 {
7175 middle = (end + begin) / 2;
7176 anchor = (*block->anchors)[middle];
7177 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7178 end = middle;
7179 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7180 begin = middle + 1;
7181 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7182 end = middle;
7183 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7184 begin = middle + 1;
7185 else
7186 return anchor;
7187 }
7188
7189 /* Create a new anchor with a unique label. */
7190 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7191 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7192 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7193 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7194
7195 /* Insert it at index BEGIN. */
7196 vec_safe_insert (block->anchors, begin, anchor);
7197 return anchor;
7198 }
7199
7200 /* Output the objects in BLOCK. */
7201
7202 static void
7203 output_object_block (struct object_block *block)
7204 {
7205 struct constant_descriptor_rtx *desc;
7206 unsigned int i;
7207 HOST_WIDE_INT offset;
7208 tree decl;
7209 rtx symbol;
7210
7211 if (!block->objects)
7212 return;
7213
7214 /* Switch to the section and make sure that the first byte is
7215 suitably aligned. */
7216 switch_to_section (block->sect);
7217 assemble_align (block->alignment);
7218
7219 /* Define the values of all anchors relative to the current section
7220 position. */
7221 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7222 targetm.asm_out.output_anchor (symbol);
7223
7224 /* Output the objects themselves. */
7225 offset = 0;
7226 FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7227 {
7228 /* Move to the object's offset, padding with zeros if necessary. */
7229 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7230 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7231 if (CONSTANT_POOL_ADDRESS_P (symbol))
7232 {
7233 desc = SYMBOL_REF_CONSTANT (symbol);
7234 output_constant_pool_1 (desc, 1);
7235 offset += GET_MODE_SIZE (desc->mode);
7236 }
7237 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7238 {
7239 HOST_WIDE_INT size;
7240 decl = SYMBOL_REF_DECL (symbol);
7241 assemble_constant_contents (DECL_INITIAL (decl), XSTR (symbol, 0),
7242 DECL_ALIGN (decl));
7243 size = get_constant_size (DECL_INITIAL (decl));
7244 offset += size;
7245 if ((flag_sanitize & SANITIZE_ADDRESS)
7246 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7247 && asan_protect_global (DECL_INITIAL (decl)))
7248 {
7249 size = asan_red_zone_size (size);
7250 assemble_zeros (size);
7251 offset += size;
7252 }
7253 }
7254 else
7255 {
7256 HOST_WIDE_INT size;
7257 decl = SYMBOL_REF_DECL (symbol);
7258 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7259 size = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
7260 offset += size;
7261 if ((flag_sanitize & SANITIZE_ADDRESS)
7262 && asan_protect_global (decl))
7263 {
7264 size = asan_red_zone_size (size);
7265 assemble_zeros (size);
7266 offset += size;
7267 }
7268 }
7269 }
7270 }
7271
7272 /* A htab_traverse callback used to call output_object_block for
7273 each member of object_block_htab. */
7274
7275 static int
7276 output_object_block_htab (void **slot, void *data ATTRIBUTE_UNUSED)
7277 {
7278 output_object_block ((struct object_block *) (*slot));
7279 return 1;
7280 }
7281
7282 /* Output the definitions of all object_blocks. */
7283
7284 void
7285 output_object_blocks (void)
7286 {
7287 htab_traverse (object_block_htab, output_object_block_htab, NULL);
7288 }
7289
7290 /* This function provides a possible implementation of the
7291 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7292 by -frecord-gcc-switches it creates a new mergeable, string section in the
7293 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7294 contains the switches in ASCII format.
7295
7296 FIXME: This code does not correctly handle double quote characters
7297 that appear inside strings, (it strips them rather than preserving them).
7298 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7299 characters - instead it treats them as sub-string separators. Since
7300 we want to emit NUL strings terminators into the object file we have to use
7301 ASM_OUTPUT_SKIP. */
7302
7303 int
7304 elf_record_gcc_switches (print_switch_type type, const char * name)
7305 {
7306 switch (type)
7307 {
7308 case SWITCH_TYPE_PASSED:
7309 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7310 ASM_OUTPUT_SKIP (asm_out_file, (unsigned HOST_WIDE_INT) 1);
7311 break;
7312
7313 case SWITCH_TYPE_DESCRIPTIVE:
7314 if (name == NULL)
7315 {
7316 /* Distinguish between invocations where name is NULL. */
7317 static bool started = false;
7318
7319 if (!started)
7320 {
7321 section * sec;
7322
7323 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7324 SECTION_DEBUG
7325 | SECTION_MERGE
7326 | SECTION_STRINGS
7327 | (SECTION_ENTSIZE & 1),
7328 NULL);
7329 switch_to_section (sec);
7330 started = true;
7331 }
7332 }
7333
7334 default:
7335 break;
7336 }
7337
7338 /* The return value is currently ignored by the caller, but must be 0.
7339 For -fverbose-asm the return value would be the number of characters
7340 emitted into the assembler file. */
7341 return 0;
7342 }
7343
7344 /* Emit text to declare externally defined symbols. It is needed to
7345 properly support non-default visibility. */
7346 void
7347 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7348 tree decl,
7349 const char *name ATTRIBUTE_UNUSED)
7350 {
7351 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7352 set in order to avoid putting out names that are never really
7353 used. */
7354 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7355 && targetm.binds_local_p (decl))
7356 maybe_assemble_visibility (decl);
7357 }
7358
7359 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7360
7361 void
7362 default_asm_output_source_filename (FILE *file, const char *name)
7363 {
7364 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7365 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7366 #else
7367 fprintf (file, "\t.file\t");
7368 output_quoted_string (file, name);
7369 putc ('\n', file);
7370 #endif
7371 }
7372
7373 /* Output a file name in the form wanted by System V. */
7374
7375 void
7376 output_file_directive (FILE *asm_file, const char *input_name)
7377 {
7378 int len;
7379 const char *na;
7380
7381 if (input_name == NULL)
7382 input_name = "<stdin>";
7383 else
7384 input_name = remap_debug_filename (input_name);
7385
7386 len = strlen (input_name);
7387 na = input_name + len;
7388
7389 /* NA gets INPUT_NAME sans directory names. */
7390 while (na > input_name)
7391 {
7392 if (IS_DIR_SEPARATOR (na[-1]))
7393 break;
7394 na--;
7395 }
7396
7397 targetm.asm_out.output_source_filename (asm_file, na);
7398 }
7399
7400 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7401 EXP. */
7402 rtx
7403 make_debug_expr_from_rtl (const_rtx exp)
7404 {
7405 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7406 enum machine_mode mode = GET_MODE (exp);
7407 rtx dval;
7408
7409 DECL_ARTIFICIAL (ddecl) = 1;
7410 if (REG_P (exp) && REG_EXPR (exp))
7411 type = TREE_TYPE (REG_EXPR (exp));
7412 else if (MEM_P (exp) && MEM_EXPR (exp))
7413 type = TREE_TYPE (MEM_EXPR (exp));
7414 else
7415 type = NULL_TREE;
7416 if (type && TYPE_MODE (type) == mode)
7417 TREE_TYPE (ddecl) = type;
7418 else
7419 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7420 DECL_MODE (ddecl) = mode;
7421 dval = gen_rtx_DEBUG_EXPR (mode);
7422 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7423 SET_DECL_RTL (ddecl, dval);
7424 return dval;
7425 }
7426
7427 #ifdef ELF_ASCII_ESCAPES
7428 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7429
7430 void
7431 default_elf_asm_output_limited_string (FILE *f, const char *s)
7432 {
7433 int escape;
7434 unsigned char c;
7435
7436 fputs (STRING_ASM_OP, f);
7437 putc ('"', f);
7438 while (*s != '\0')
7439 {
7440 c = *s;
7441 escape = ELF_ASCII_ESCAPES[c];
7442 switch (escape)
7443 {
7444 case 0:
7445 putc (c, f);
7446 break;
7447 case 1:
7448 /* TODO: Print in hex with fast function, important for -flto. */
7449 fprintf (f, "\\%03o", c);
7450 break;
7451 default:
7452 putc ('\\', f);
7453 putc (escape, f);
7454 break;
7455 }
7456 s++;
7457 }
7458 putc ('\"', f);
7459 putc ('\n', f);
7460 }
7461
7462 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7463
7464 void
7465 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7466 {
7467 const char *limit = s + len;
7468 const char *last_null = NULL;
7469 unsigned bytes_in_chunk = 0;
7470 unsigned char c;
7471 int escape;
7472
7473 for (; s < limit; s++)
7474 {
7475 const char *p;
7476
7477 if (bytes_in_chunk >= 60)
7478 {
7479 putc ('\"', f);
7480 putc ('\n', f);
7481 bytes_in_chunk = 0;
7482 }
7483
7484 if (s > last_null)
7485 {
7486 for (p = s; p < limit && *p != '\0'; p++)
7487 continue;
7488 last_null = p;
7489 }
7490 else
7491 p = last_null;
7492
7493 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7494 {
7495 if (bytes_in_chunk > 0)
7496 {
7497 putc ('\"', f);
7498 putc ('\n', f);
7499 bytes_in_chunk = 0;
7500 }
7501
7502 default_elf_asm_output_limited_string (f, s);
7503 s = p;
7504 }
7505 else
7506 {
7507 if (bytes_in_chunk == 0)
7508 fputs (ASCII_DATA_ASM_OP "\"", f);
7509
7510 c = *s;
7511 escape = ELF_ASCII_ESCAPES[c];
7512 switch (escape)
7513 {
7514 case 0:
7515 putc (c, f);
7516 bytes_in_chunk++;
7517 break;
7518 case 1:
7519 /* TODO: Print in hex with fast function, important for -flto. */
7520 fprintf (f, "\\%03o", c);
7521 bytes_in_chunk += 4;
7522 break;
7523 default:
7524 putc ('\\', f);
7525 putc (escape, f);
7526 bytes_in_chunk += 2;
7527 break;
7528 }
7529
7530 }
7531 }
7532
7533 if (bytes_in_chunk > 0)
7534 {
7535 putc ('\"', f);
7536 putc ('\n', f);
7537 }
7538 }
7539 #endif
7540
7541 static GTY(()) section *elf_init_array_section;
7542 static GTY(()) section *elf_fini_array_section;
7543
7544 static section *
7545 get_elf_initfini_array_priority_section (int priority,
7546 bool constructor_p)
7547 {
7548 section *sec;
7549 if (priority != DEFAULT_INIT_PRIORITY)
7550 {
7551 char buf[18];
7552 sprintf (buf, "%s.%.5u",
7553 constructor_p ? ".init_array" : ".fini_array",
7554 priority);
7555 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7556 }
7557 else
7558 {
7559 if (constructor_p)
7560 {
7561 if (elf_init_array_section == NULL)
7562 elf_init_array_section
7563 = get_section (".init_array",
7564 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7565 sec = elf_init_array_section;
7566 }
7567 else
7568 {
7569 if (elf_fini_array_section == NULL)
7570 elf_fini_array_section
7571 = get_section (".fini_array",
7572 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7573 sec = elf_fini_array_section;
7574 }
7575 }
7576 return sec;
7577 }
7578
7579 /* Use .init_array section for constructors. */
7580
7581 void
7582 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7583 {
7584 section *sec = get_elf_initfini_array_priority_section (priority,
7585 true);
7586 assemble_addr_to_section (symbol, sec);
7587 }
7588
7589 /* Use .fini_array section for destructors. */
7590
7591 void
7592 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7593 {
7594 section *sec = get_elf_initfini_array_priority_section (priority,
7595 false);
7596 assemble_addr_to_section (symbol, sec);
7597 }
7598
7599 /* Default TARGET_ASM_OUTPUT_IDENT hook.
7600
7601 This is a bit of a cheat. The real default is a no-op, but this
7602 hook is the default for all targets with a .ident directive. */
7603
7604 void
7605 default_asm_output_ident_directive (const char *ident_str)
7606 {
7607 const char *ident_asm_op = "\t.ident\t";
7608
7609 /* If we are still in the front end, do not write out the string
7610 to asm_out_file. Instead, add a fake top-level asm statement.
7611 This allows the front ends to use this hook without actually
7612 writing to asm_out_file, to handle #ident or Pragma Ident. */
7613 if (cgraph_state == CGRAPH_STATE_PARSING)
7614 {
7615 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
7616 add_asm_node (build_string (strlen (buf), buf));
7617 }
7618 else
7619 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
7620 }
7621
7622 #include "gt-varasm.h"