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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 (!tree_fits_uhwi_p (DECL_SIZE_UNIT (decl)))
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_to_uhwi (DECL_SIZE_UNIT (decl));
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_to_uhwi (DECL_SIZE_UNIT (decl)),
1954 get_variable_align (decl));
1955 else
1956 /* Leave space for it. */
1957 assemble_zeros (tree_to_uhwi (DECL_SIZE_UNIT (decl)));
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_to_uhwi (DECL_SIZE_UNIT (decl));
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 && tree_fits_shwi_p (byte_position (TREE_OPERAND (target, 1))))
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_to_uhwi (TYPE_SIZE_UNIT (TREE_TYPE (target)))
2735 * tree_to_shwi (TREE_OPERAND (target, 1)));
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).to_short_addr ();
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_ELT (exp, 0);
2822 len = TREE_INT_CST_NUNITS (exp) * sizeof (HOST_WIDE_INT);
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 int i;
3530
3531 x = *xp;
3532 code = GET_CODE (x);
3533 mode = GET_MODE (x);
3534 h = (hashval_t) code * 1048573 + mode;
3535
3536 switch (code)
3537 {
3538 case CONST_INT:
3539 hwi = INTVAL (x);
3540
3541 fold_hwi:
3542 {
3543 int shift = sizeof (hashval_t) * CHAR_BIT;
3544 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3545
3546 h ^= (hashval_t) hwi;
3547 for (i = 1; i < n; ++i)
3548 {
3549 hwi >>= shift;
3550 h ^= (hashval_t) hwi;
3551 }
3552 }
3553 break;
3554
3555 case CONST_WIDE_INT:
3556 hwi = GET_MODE_PRECISION (mode);
3557 {
3558 for (i = 0; i < CONST_WIDE_INT_NUNITS (x); i++)
3559 hwi ^= CONST_WIDE_INT_ELT (x, i);
3560 goto fold_hwi;
3561 }
3562
3563 case CONST_DOUBLE:
3564 if (TARGET_SUPPORTS_WIDE_INT == 0 && mode == VOIDmode)
3565 {
3566 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3567 goto fold_hwi;
3568 }
3569 else
3570 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3571 break;
3572
3573 case CONST_FIXED:
3574 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3575 break;
3576
3577 case CONST_VECTOR:
3578 {
3579 int i;
3580 for (i = XVECLEN (x, 0); i-- > 0; )
3581 h = h * 251 + const_rtx_hash_1 (&XVECEXP (x, 0, i), data);
3582 }
3583 break;
3584
3585 case SYMBOL_REF:
3586 h ^= htab_hash_string (XSTR (x, 0));
3587 break;
3588
3589 case LABEL_REF:
3590 h = h * 251 + CODE_LABEL_NUMBER (XEXP (x, 0));
3591 break;
3592
3593 case UNSPEC:
3594 case UNSPEC_VOLATILE:
3595 h = h * 251 + XINT (x, 1);
3596 break;
3597
3598 default:
3599 break;
3600 }
3601
3602 hp = (hashval_t *) data;
3603 *hp = *hp * 509 + h;
3604 return 0;
3605 }
3606
3607 /* Compute a hash value for X, which should be a constant. */
3608
3609 static hashval_t
3610 const_rtx_hash (rtx x)
3611 {
3612 hashval_t h = 0;
3613 for_each_rtx (&x, const_rtx_hash_1, &h);
3614 return h;
3615 }
3616
3617 \f
3618 /* Create and return a new rtx constant pool. */
3619
3620 static struct rtx_constant_pool *
3621 create_constant_pool (void)
3622 {
3623 struct rtx_constant_pool *pool;
3624
3625 pool = ggc_alloc_rtx_constant_pool ();
3626 pool->const_rtx_htab = htab_create_ggc (31, const_desc_rtx_hash,
3627 const_desc_rtx_eq, NULL);
3628 pool->first = NULL;
3629 pool->last = NULL;
3630 pool->offset = 0;
3631 return pool;
3632 }
3633
3634 /* Initialize constant pool hashing for a new function. */
3635
3636 void
3637 init_varasm_status (void)
3638 {
3639 crtl->varasm.pool = create_constant_pool ();
3640 crtl->varasm.deferred_constants = 0;
3641 }
3642 \f
3643 /* Given a MINUS expression, simplify it if both sides
3644 include the same symbol. */
3645
3646 rtx
3647 simplify_subtraction (rtx x)
3648 {
3649 rtx r = simplify_rtx (x);
3650 return r ? r : x;
3651 }
3652 \f
3653 /* Given a constant rtx X, make (or find) a memory constant for its value
3654 and return a MEM rtx to refer to it in memory. */
3655
3656 rtx
3657 force_const_mem (enum machine_mode mode, rtx x)
3658 {
3659 struct constant_descriptor_rtx *desc, tmp;
3660 struct rtx_constant_pool *pool;
3661 char label[256];
3662 rtx def, symbol;
3663 hashval_t hash;
3664 unsigned int align;
3665 void **slot;
3666
3667 /* If we're not allowed to drop X into the constant pool, don't. */
3668 if (targetm.cannot_force_const_mem (mode, x))
3669 return NULL_RTX;
3670
3671 /* Record that this function has used a constant pool entry. */
3672 crtl->uses_const_pool = 1;
3673
3674 /* Decide which pool to use. */
3675 pool = (targetm.use_blocks_for_constant_p (mode, x)
3676 ? shared_constant_pool
3677 : crtl->varasm.pool);
3678
3679 /* Lookup the value in the hashtable. */
3680 tmp.constant = x;
3681 tmp.mode = mode;
3682 hash = const_rtx_hash (x);
3683 slot = htab_find_slot_with_hash (pool->const_rtx_htab, &tmp, hash, INSERT);
3684 desc = (struct constant_descriptor_rtx *) *slot;
3685
3686 /* If the constant was already present, return its memory. */
3687 if (desc)
3688 return copy_rtx (desc->mem);
3689
3690 /* Otherwise, create a new descriptor. */
3691 desc = ggc_alloc_constant_descriptor_rtx ();
3692 *slot = desc;
3693
3694 /* Align the location counter as required by EXP's data type. */
3695 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3696 #ifdef CONSTANT_ALIGNMENT
3697 {
3698 tree type = lang_hooks.types.type_for_mode (mode, 0);
3699 if (type != NULL_TREE)
3700 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3701 }
3702 #endif
3703
3704 pool->offset += (align / BITS_PER_UNIT) - 1;
3705 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3706
3707 desc->next = NULL;
3708 desc->constant = copy_rtx (tmp.constant);
3709 desc->offset = pool->offset;
3710 desc->hash = hash;
3711 desc->mode = mode;
3712 desc->align = align;
3713 desc->labelno = const_labelno;
3714 desc->mark = 0;
3715
3716 pool->offset += GET_MODE_SIZE (mode);
3717 if (pool->last)
3718 pool->last->next = desc;
3719 else
3720 pool->first = pool->last = desc;
3721 pool->last = desc;
3722
3723 /* Create a string containing the label name, in LABEL. */
3724 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3725 ++const_labelno;
3726
3727 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3728 the constants pool. */
3729 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3730 {
3731 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3732 symbol = create_block_symbol (ggc_strdup (label),
3733 get_block_for_section (sect), -1);
3734 }
3735 else
3736 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3737 desc->sym = symbol;
3738 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3739 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3740 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3741
3742 /* Construct the MEM. */
3743 desc->mem = def = gen_const_mem (mode, symbol);
3744 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3745 set_mem_align (def, align);
3746
3747 /* If we're dropping a label to the constant pool, make sure we
3748 don't delete it. */
3749 if (GET_CODE (x) == LABEL_REF)
3750 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3751
3752 return copy_rtx (def);
3753 }
3754 \f
3755 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3756
3757 rtx
3758 get_pool_constant (rtx addr)
3759 {
3760 return SYMBOL_REF_CONSTANT (addr)->constant;
3761 }
3762
3763 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3764 and whether it has been output or not. */
3765
3766 rtx
3767 get_pool_constant_mark (rtx addr, bool *pmarked)
3768 {
3769 struct constant_descriptor_rtx *desc;
3770
3771 desc = SYMBOL_REF_CONSTANT (addr);
3772 *pmarked = (desc->mark != 0);
3773 return desc->constant;
3774 }
3775
3776 /* Similar, return the mode. */
3777
3778 enum machine_mode
3779 get_pool_mode (const_rtx addr)
3780 {
3781 return SYMBOL_REF_CONSTANT (addr)->mode;
3782 }
3783
3784 /* Return the size of the constant pool. */
3785
3786 int
3787 get_pool_size (void)
3788 {
3789 return crtl->varasm.pool->offset;
3790 }
3791 \f
3792 /* Worker function for output_constant_pool_1. Emit assembly for X
3793 in MODE with known alignment ALIGN. */
3794
3795 static void
3796 output_constant_pool_2 (enum machine_mode mode, rtx x, unsigned int align)
3797 {
3798 switch (GET_MODE_CLASS (mode))
3799 {
3800 case MODE_FLOAT:
3801 case MODE_DECIMAL_FLOAT:
3802 {
3803 REAL_VALUE_TYPE r;
3804
3805 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3806 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3807 assemble_real (r, mode, align);
3808 break;
3809 }
3810
3811 case MODE_INT:
3812 case MODE_PARTIAL_INT:
3813 case MODE_FRACT:
3814 case MODE_UFRACT:
3815 case MODE_ACCUM:
3816 case MODE_UACCUM:
3817 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3818 break;
3819
3820 case MODE_VECTOR_FLOAT:
3821 case MODE_VECTOR_INT:
3822 case MODE_VECTOR_FRACT:
3823 case MODE_VECTOR_UFRACT:
3824 case MODE_VECTOR_ACCUM:
3825 case MODE_VECTOR_UACCUM:
3826 {
3827 int i, units;
3828 enum machine_mode submode = GET_MODE_INNER (mode);
3829 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3830
3831 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3832 units = CONST_VECTOR_NUNITS (x);
3833
3834 for (i = 0; i < units; i++)
3835 {
3836 rtx elt = CONST_VECTOR_ELT (x, i);
3837 output_constant_pool_2 (submode, elt, i ? subalign : align);
3838 }
3839 }
3840 break;
3841
3842 default:
3843 gcc_unreachable ();
3844 }
3845 }
3846
3847 /* Worker function for output_constant_pool. Emit constant DESC,
3848 giving it ALIGN bits of alignment. */
3849
3850 static void
3851 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3852 unsigned int align)
3853 {
3854 rtx x, tmp;
3855
3856 x = desc->constant;
3857
3858 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3859 whose CODE_LABEL has been deleted. This can occur if a jump table
3860 is eliminated by optimization. If so, write a constant of zero
3861 instead. Note that this can also happen by turning the
3862 CODE_LABEL into a NOTE. */
3863 /* ??? This seems completely and utterly wrong. Certainly it's
3864 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3865 functioning even with INSN_DELETED_P and friends. */
3866
3867 tmp = x;
3868 switch (GET_CODE (tmp))
3869 {
3870 case CONST:
3871 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3872 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
3873 break;
3874 tmp = XEXP (XEXP (tmp, 0), 0);
3875 /* FALLTHRU */
3876
3877 case LABEL_REF:
3878 tmp = XEXP (tmp, 0);
3879 gcc_assert (!INSN_DELETED_P (tmp));
3880 gcc_assert (!NOTE_P (tmp)
3881 || NOTE_KIND (tmp) != NOTE_INSN_DELETED);
3882 break;
3883
3884 default:
3885 break;
3886 }
3887
3888 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3889 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3890 align, desc->labelno, done);
3891 #endif
3892
3893 assemble_align (align);
3894
3895 /* Output the label. */
3896 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3897
3898 /* Output the data. */
3899 output_constant_pool_2 (desc->mode, x, align);
3900
3901 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3902 sections have proper size. */
3903 if (align > GET_MODE_BITSIZE (desc->mode)
3904 && in_section
3905 && (in_section->common.flags & SECTION_MERGE))
3906 assemble_align (align);
3907
3908 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3909 done:
3910 #endif
3911 return;
3912 }
3913
3914 /* Given a SYMBOL_REF CURRENT_RTX, mark it and all constants it refers
3915 to as used. Emit referenced deferred strings. This function can
3916 be used with for_each_rtx to mark all SYMBOL_REFs in an rtx. */
3917
3918 static int
3919 mark_constant (rtx *current_rtx, void *data ATTRIBUTE_UNUSED)
3920 {
3921 rtx x = *current_rtx;
3922
3923 if (x == NULL_RTX || GET_CODE (x) != SYMBOL_REF)
3924 return 0;
3925
3926 if (CONSTANT_POOL_ADDRESS_P (x))
3927 {
3928 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
3929 if (desc->mark == 0)
3930 {
3931 desc->mark = 1;
3932 for_each_rtx (&desc->constant, mark_constant, NULL);
3933 }
3934 }
3935 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3936 {
3937 tree decl = SYMBOL_REF_DECL (x);
3938 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
3939 {
3940 n_deferred_constants--;
3941 output_constant_def_contents (x);
3942 }
3943 }
3944
3945 return -1;
3946 }
3947
3948 /* Look through appropriate parts of INSN, marking all entries in the
3949 constant pool which are actually being used. Entries that are only
3950 referenced by other constants are also marked as used. Emit
3951 deferred strings that are used. */
3952
3953 static void
3954 mark_constants (rtx insn)
3955 {
3956 if (!INSN_P (insn))
3957 return;
3958
3959 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3960 insns, not any notes that may be attached. We don't want to mark
3961 a constant just because it happens to appear in a REG_EQUIV note. */
3962 if (GET_CODE (PATTERN (insn)) == SEQUENCE)
3963 {
3964 rtx seq = PATTERN (insn);
3965 int i, n = XVECLEN (seq, 0);
3966 for (i = 0; i < n; ++i)
3967 {
3968 rtx subinsn = XVECEXP (seq, 0, i);
3969 if (INSN_P (subinsn))
3970 for_each_rtx (&PATTERN (subinsn), mark_constant, NULL);
3971 }
3972 }
3973 else
3974 for_each_rtx (&PATTERN (insn), mark_constant, NULL);
3975 }
3976
3977 /* Look through the instructions for this function, and mark all the
3978 entries in POOL which are actually being used. Emit deferred constants
3979 which have indeed been used. */
3980
3981 static void
3982 mark_constant_pool (void)
3983 {
3984 rtx insn;
3985
3986 if (!crtl->uses_const_pool && n_deferred_constants == 0)
3987 return;
3988
3989 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3990 mark_constants (insn);
3991 }
3992
3993 /* Write all the constants in POOL. */
3994
3995 static void
3996 output_constant_pool_contents (struct rtx_constant_pool *pool)
3997 {
3998 struct constant_descriptor_rtx *desc;
3999
4000 for (desc = pool->first; desc ; desc = desc->next)
4001 if (desc->mark)
4002 {
4003 /* If the constant is part of an object_block, make sure that
4004 the constant has been positioned within its block, but do not
4005 write out its definition yet. output_object_blocks will do
4006 that later. */
4007 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
4008 && SYMBOL_REF_BLOCK (desc->sym))
4009 place_block_symbol (desc->sym);
4010 else
4011 {
4012 switch_to_section (targetm.asm_out.select_rtx_section
4013 (desc->mode, desc->constant, desc->align));
4014 output_constant_pool_1 (desc, desc->align);
4015 }
4016 }
4017 }
4018
4019 /* Mark all constants that are used in the current function, then write
4020 out the function's private constant pool. */
4021
4022 static void
4023 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
4024 tree fndecl ATTRIBUTE_UNUSED)
4025 {
4026 struct rtx_constant_pool *pool = crtl->varasm.pool;
4027
4028 /* It is possible for gcc to call force_const_mem and then to later
4029 discard the instructions which refer to the constant. In such a
4030 case we do not need to output the constant. */
4031 mark_constant_pool ();
4032
4033 #ifdef ASM_OUTPUT_POOL_PROLOGUE
4034 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
4035 #endif
4036
4037 output_constant_pool_contents (pool);
4038
4039 #ifdef ASM_OUTPUT_POOL_EPILOGUE
4040 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
4041 #endif
4042 }
4043 \f
4044 /* Write the contents of the shared constant pool. */
4045
4046 void
4047 output_shared_constant_pool (void)
4048 {
4049 output_constant_pool_contents (shared_constant_pool);
4050 }
4051 \f
4052 /* Determine what kind of relocations EXP may need. */
4053
4054 int
4055 compute_reloc_for_constant (tree exp)
4056 {
4057 int reloc = 0, reloc2;
4058 tree tem;
4059
4060 switch (TREE_CODE (exp))
4061 {
4062 case ADDR_EXPR:
4063 case FDESC_EXPR:
4064 /* Go inside any operations that get_inner_reference can handle and see
4065 if what's inside is a constant: no need to do anything here for
4066 addresses of variables or functions. */
4067 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4068 tem = TREE_OPERAND (tem, 0))
4069 ;
4070
4071 if (TREE_CODE (tem) == MEM_REF
4072 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4073 {
4074 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4075 break;
4076 }
4077
4078 if (TREE_PUBLIC (tem))
4079 reloc |= 2;
4080 else
4081 reloc |= 1;
4082 break;
4083
4084 case PLUS_EXPR:
4085 case POINTER_PLUS_EXPR:
4086 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4087 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4088 break;
4089
4090 case MINUS_EXPR:
4091 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4092 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4093 /* The difference of two local labels is computable at link time. */
4094 if (reloc == 1 && reloc2 == 1)
4095 reloc = 0;
4096 else
4097 reloc |= reloc2;
4098 break;
4099
4100 CASE_CONVERT:
4101 case VIEW_CONVERT_EXPR:
4102 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4103 break;
4104
4105 case CONSTRUCTOR:
4106 {
4107 unsigned HOST_WIDE_INT idx;
4108 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4109 if (tem != 0)
4110 reloc |= compute_reloc_for_constant (tem);
4111 }
4112 break;
4113
4114 default:
4115 break;
4116 }
4117 return reloc;
4118 }
4119
4120 /* Find all the constants whose addresses are referenced inside of EXP,
4121 and make sure assembler code with a label has been output for each one.
4122 Indicate whether an ADDR_EXPR has been encountered. */
4123
4124 static void
4125 output_addressed_constants (tree exp)
4126 {
4127 tree tem;
4128
4129 switch (TREE_CODE (exp))
4130 {
4131 case ADDR_EXPR:
4132 case FDESC_EXPR:
4133 /* Go inside any operations that get_inner_reference can handle and see
4134 if what's inside is a constant: no need to do anything here for
4135 addresses of variables or functions. */
4136 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4137 tem = TREE_OPERAND (tem, 0))
4138 ;
4139
4140 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4141 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4142 tem = DECL_INITIAL (tem);
4143
4144 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4145 output_constant_def (tem, 0);
4146
4147 if (TREE_CODE (tem) == MEM_REF)
4148 output_addressed_constants (TREE_OPERAND (tem, 0));
4149 break;
4150
4151 case PLUS_EXPR:
4152 case POINTER_PLUS_EXPR:
4153 case MINUS_EXPR:
4154 output_addressed_constants (TREE_OPERAND (exp, 1));
4155 /* Fall through. */
4156
4157 CASE_CONVERT:
4158 case VIEW_CONVERT_EXPR:
4159 output_addressed_constants (TREE_OPERAND (exp, 0));
4160 break;
4161
4162 case CONSTRUCTOR:
4163 {
4164 unsigned HOST_WIDE_INT idx;
4165 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4166 if (tem != 0)
4167 output_addressed_constants (tem);
4168 }
4169 break;
4170
4171 default:
4172 break;
4173 }
4174 }
4175 \f
4176 /* Whether a constructor CTOR is a valid static constant initializer if all
4177 its elements are. This used to be internal to initializer_constant_valid_p
4178 and has been exposed to let other functions like categorize_ctor_elements
4179 evaluate the property while walking a constructor for other purposes. */
4180
4181 bool
4182 constructor_static_from_elts_p (const_tree ctor)
4183 {
4184 return (TREE_CONSTANT (ctor)
4185 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4186 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4187 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4188 }
4189
4190 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4191 tree *cache);
4192
4193 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4194 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4195 which are valid when ENDTYPE is an integer of any size; in
4196 particular, this does not accept a pointer minus a constant. This
4197 returns null_pointer_node if the VALUE is an absolute constant
4198 which can be used to initialize a static variable. Otherwise it
4199 returns NULL. */
4200
4201 static tree
4202 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4203 {
4204 tree op0, op1;
4205
4206 if (!INTEGRAL_TYPE_P (endtype))
4207 return NULL_TREE;
4208
4209 op0 = TREE_OPERAND (value, 0);
4210 op1 = TREE_OPERAND (value, 1);
4211
4212 /* Like STRIP_NOPS except allow the operand mode to widen. This
4213 works around a feature of fold that simplifies (int)(p1 - p2) to
4214 ((int)p1 - (int)p2) under the theory that the narrower operation
4215 is cheaper. */
4216
4217 while (CONVERT_EXPR_P (op0)
4218 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4219 {
4220 tree inner = TREE_OPERAND (op0, 0);
4221 if (inner == error_mark_node
4222 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4223 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
4224 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4225 break;
4226 op0 = inner;
4227 }
4228
4229 while (CONVERT_EXPR_P (op1)
4230 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4231 {
4232 tree inner = TREE_OPERAND (op1, 0);
4233 if (inner == error_mark_node
4234 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4235 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
4236 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4237 break;
4238 op1 = inner;
4239 }
4240
4241 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4242 if (!op0)
4243 return NULL_TREE;
4244
4245 op1 = initializer_constant_valid_p_1 (op1, endtype,
4246 cache ? cache + 2 : NULL);
4247 /* Both initializers must be known. */
4248 if (op1)
4249 {
4250 if (op0 == op1
4251 && (op0 == null_pointer_node
4252 || TREE_CODE (value) == MINUS_EXPR))
4253 return null_pointer_node;
4254
4255 /* Support differences between labels. */
4256 if (TREE_CODE (op0) == LABEL_DECL
4257 && TREE_CODE (op1) == LABEL_DECL)
4258 return null_pointer_node;
4259
4260 if (TREE_CODE (op0) == STRING_CST
4261 && TREE_CODE (op1) == STRING_CST
4262 && operand_equal_p (op0, op1, 1))
4263 return null_pointer_node;
4264 }
4265
4266 return NULL_TREE;
4267 }
4268
4269 /* Helper function of initializer_constant_valid_p.
4270 Return nonzero if VALUE is a valid constant-valued expression
4271 for use in initializing a static variable; one that can be an
4272 element of a "constant" initializer.
4273
4274 Return null_pointer_node if the value is absolute;
4275 if it is relocatable, return the variable that determines the relocation.
4276 We assume that VALUE has been folded as much as possible;
4277 therefore, we do not need to check for such things as
4278 arithmetic-combinations of integers.
4279
4280 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4281
4282 static tree
4283 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4284 {
4285 tree ret;
4286
4287 switch (TREE_CODE (value))
4288 {
4289 case CONSTRUCTOR:
4290 if (constructor_static_from_elts_p (value))
4291 {
4292 unsigned HOST_WIDE_INT idx;
4293 tree elt;
4294 bool absolute = true;
4295
4296 if (cache && cache[0] == value)
4297 return cache[1];
4298 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4299 {
4300 tree reloc;
4301 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4302 NULL);
4303 if (!reloc)
4304 {
4305 if (cache)
4306 {
4307 cache[0] = value;
4308 cache[1] = NULL_TREE;
4309 }
4310 return NULL_TREE;
4311 }
4312 if (reloc != null_pointer_node)
4313 absolute = false;
4314 }
4315 /* For a non-absolute relocation, there is no single
4316 variable that can be "the variable that determines the
4317 relocation." */
4318 if (cache)
4319 {
4320 cache[0] = value;
4321 cache[1] = absolute ? null_pointer_node : error_mark_node;
4322 }
4323 return absolute ? null_pointer_node : error_mark_node;
4324 }
4325
4326 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4327
4328 case INTEGER_CST:
4329 case VECTOR_CST:
4330 case REAL_CST:
4331 case FIXED_CST:
4332 case STRING_CST:
4333 case COMPLEX_CST:
4334 return null_pointer_node;
4335
4336 case ADDR_EXPR:
4337 case FDESC_EXPR:
4338 {
4339 tree op0 = staticp (TREE_OPERAND (value, 0));
4340 if (op0)
4341 {
4342 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4343 to be a constant, this is old-skool offsetof-like nonsense. */
4344 if (TREE_CODE (op0) == INDIRECT_REF
4345 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4346 return null_pointer_node;
4347 /* Taking the address of a nested function involves a trampoline,
4348 unless we don't need or want one. */
4349 if (TREE_CODE (op0) == FUNCTION_DECL
4350 && DECL_STATIC_CHAIN (op0)
4351 && !TREE_NO_TRAMPOLINE (value))
4352 return NULL_TREE;
4353 /* "&{...}" requires a temporary to hold the constructed
4354 object. */
4355 if (TREE_CODE (op0) == CONSTRUCTOR)
4356 return NULL_TREE;
4357 }
4358 return op0;
4359 }
4360
4361 case NON_LVALUE_EXPR:
4362 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4363 endtype, cache);
4364
4365 case VIEW_CONVERT_EXPR:
4366 {
4367 tree src = TREE_OPERAND (value, 0);
4368 tree src_type = TREE_TYPE (src);
4369 tree dest_type = TREE_TYPE (value);
4370
4371 /* Allow view-conversions from aggregate to non-aggregate type only
4372 if the bit pattern is fully preserved afterwards; otherwise, the
4373 RTL expander won't be able to apply a subsequent transformation
4374 to the underlying constructor. */
4375 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4376 {
4377 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4378 return initializer_constant_valid_p_1 (src, endtype, cache);
4379 else
4380 return NULL_TREE;
4381 }
4382
4383 /* Allow all other kinds of view-conversion. */
4384 return initializer_constant_valid_p_1 (src, endtype, cache);
4385 }
4386
4387 CASE_CONVERT:
4388 {
4389 tree src = TREE_OPERAND (value, 0);
4390 tree src_type = TREE_TYPE (src);
4391 tree dest_type = TREE_TYPE (value);
4392
4393 /* Allow conversions between pointer types, floating-point
4394 types, and offset types. */
4395 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4396 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4397 || (TREE_CODE (dest_type) == OFFSET_TYPE
4398 && TREE_CODE (src_type) == OFFSET_TYPE))
4399 return initializer_constant_valid_p_1 (src, endtype, cache);
4400
4401 /* Allow length-preserving conversions between integer types. */
4402 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4403 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4404 return initializer_constant_valid_p_1 (src, endtype, cache);
4405
4406 /* Allow conversions between other integer types only if
4407 explicit value. */
4408 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type))
4409 {
4410 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4411 if (inner == null_pointer_node)
4412 return null_pointer_node;
4413 break;
4414 }
4415
4416 /* Allow (int) &foo provided int is as wide as a pointer. */
4417 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4418 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4419 return initializer_constant_valid_p_1 (src, endtype, cache);
4420
4421 /* Likewise conversions from int to pointers, but also allow
4422 conversions from 0. */
4423 if ((POINTER_TYPE_P (dest_type)
4424 || TREE_CODE (dest_type) == OFFSET_TYPE)
4425 && INTEGRAL_TYPE_P (src_type))
4426 {
4427 if (TREE_CODE (src) == INTEGER_CST
4428 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4429 return null_pointer_node;
4430 if (integer_zerop (src))
4431 return null_pointer_node;
4432 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4433 return initializer_constant_valid_p_1 (src, endtype, cache);
4434 }
4435
4436 /* Allow conversions to struct or union types if the value
4437 inside is okay. */
4438 if (TREE_CODE (dest_type) == RECORD_TYPE
4439 || TREE_CODE (dest_type) == UNION_TYPE)
4440 return initializer_constant_valid_p_1 (src, endtype, cache);
4441 }
4442 break;
4443
4444 case POINTER_PLUS_EXPR:
4445 case PLUS_EXPR:
4446 /* Any valid floating-point constants will have been folded by now;
4447 with -frounding-math we hit this with addition of two constants. */
4448 if (TREE_CODE (endtype) == REAL_TYPE)
4449 return NULL_TREE;
4450 if (cache && cache[0] == value)
4451 return cache[1];
4452 if (! INTEGRAL_TYPE_P (endtype)
4453 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4454 {
4455 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4456 tree valid0
4457 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4458 endtype, ncache);
4459 tree valid1
4460 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4461 endtype, ncache + 2);
4462 /* If either term is absolute, use the other term's relocation. */
4463 if (valid0 == null_pointer_node)
4464 ret = valid1;
4465 else if (valid1 == null_pointer_node)
4466 ret = valid0;
4467 /* Support narrowing pointer differences. */
4468 else
4469 ret = narrowing_initializer_constant_valid_p (value, endtype,
4470 ncache);
4471 }
4472 else
4473 /* Support narrowing pointer differences. */
4474 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4475 if (cache)
4476 {
4477 cache[0] = value;
4478 cache[1] = ret;
4479 }
4480 return ret;
4481
4482 case MINUS_EXPR:
4483 if (TREE_CODE (endtype) == REAL_TYPE)
4484 return NULL_TREE;
4485 if (cache && cache[0] == value)
4486 return cache[1];
4487 if (! INTEGRAL_TYPE_P (endtype)
4488 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4489 {
4490 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4491 tree valid0
4492 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4493 endtype, ncache);
4494 tree valid1
4495 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4496 endtype, ncache + 2);
4497 /* Win if second argument is absolute. */
4498 if (valid1 == null_pointer_node)
4499 ret = valid0;
4500 /* Win if both arguments have the same relocation.
4501 Then the value is absolute. */
4502 else if (valid0 == valid1 && valid0 != 0)
4503 ret = null_pointer_node;
4504 /* Since GCC guarantees that string constants are unique in the
4505 generated code, a subtraction between two copies of the same
4506 constant string is absolute. */
4507 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4508 && valid1 && TREE_CODE (valid1) == STRING_CST
4509 && operand_equal_p (valid0, valid1, 1))
4510 ret = null_pointer_node;
4511 /* Support narrowing differences. */
4512 else
4513 ret = narrowing_initializer_constant_valid_p (value, endtype,
4514 ncache);
4515 }
4516 else
4517 /* Support narrowing differences. */
4518 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4519 if (cache)
4520 {
4521 cache[0] = value;
4522 cache[1] = ret;
4523 }
4524 return ret;
4525
4526 default:
4527 break;
4528 }
4529
4530 return NULL_TREE;
4531 }
4532
4533 /* Return nonzero if VALUE is a valid constant-valued expression
4534 for use in initializing a static variable; one that can be an
4535 element of a "constant" initializer.
4536
4537 Return null_pointer_node if the value is absolute;
4538 if it is relocatable, return the variable that determines the relocation.
4539 We assume that VALUE has been folded as much as possible;
4540 therefore, we do not need to check for such things as
4541 arithmetic-combinations of integers. */
4542 tree
4543 initializer_constant_valid_p (tree value, tree endtype)
4544 {
4545 return initializer_constant_valid_p_1 (value, endtype, NULL);
4546 }
4547 \f
4548 /* Return true if VALUE is a valid constant-valued expression
4549 for use in initializing a static bit-field; one that can be
4550 an element of a "constant" initializer. */
4551
4552 bool
4553 initializer_constant_valid_for_bitfield_p (tree value)
4554 {
4555 /* For bitfields we support integer constants or possibly nested aggregates
4556 of such. */
4557 switch (TREE_CODE (value))
4558 {
4559 case CONSTRUCTOR:
4560 {
4561 unsigned HOST_WIDE_INT idx;
4562 tree elt;
4563
4564 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4565 if (!initializer_constant_valid_for_bitfield_p (elt))
4566 return false;
4567 return true;
4568 }
4569
4570 case INTEGER_CST:
4571 case REAL_CST:
4572 return true;
4573
4574 case VIEW_CONVERT_EXPR:
4575 case NON_LVALUE_EXPR:
4576 return
4577 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4578
4579 default:
4580 break;
4581 }
4582
4583 return false;
4584 }
4585
4586 /* output_constructor outer state of relevance in recursive calls, typically
4587 for nested aggregate bitfields. */
4588
4589 typedef struct {
4590 unsigned int bit_offset; /* current position in ... */
4591 int byte; /* ... the outer byte buffer. */
4592 } oc_outer_state;
4593
4594 static unsigned HOST_WIDE_INT
4595 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int,
4596 oc_outer_state *);
4597
4598 /* Output assembler code for constant EXP, with no label.
4599 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4600 Assumes output_addressed_constants has been done on EXP already.
4601
4602 Generate exactly SIZE bytes of assembler data, padding at the end
4603 with zeros if necessary. SIZE must always be specified.
4604
4605 SIZE is important for structure constructors,
4606 since trailing members may have been omitted from the constructor.
4607 It is also important for initialization of arrays from string constants
4608 since the full length of the string constant might not be wanted.
4609 It is also needed for initialization of unions, where the initializer's
4610 type is just one member, and that may not be as long as the union.
4611
4612 There a case in which we would fail to output exactly SIZE bytes:
4613 for a structure constructor that wants to produce more than SIZE bytes.
4614 But such constructors will never be generated for any possible input.
4615
4616 ALIGN is the alignment of the data in bits. */
4617
4618 void
4619 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align)
4620 {
4621 enum tree_code code;
4622 unsigned HOST_WIDE_INT thissize;
4623
4624 if (size == 0 || flag_syntax_only)
4625 return;
4626
4627 /* See if we're trying to initialize a pointer in a non-default mode
4628 to the address of some declaration somewhere. If the target says
4629 the mode is valid for pointers, assume the target has a way of
4630 resolving it. */
4631 if (TREE_CODE (exp) == NOP_EXPR
4632 && POINTER_TYPE_P (TREE_TYPE (exp))
4633 && targetm.addr_space.valid_pointer_mode
4634 (TYPE_MODE (TREE_TYPE (exp)),
4635 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4636 {
4637 tree saved_type = TREE_TYPE (exp);
4638
4639 /* Peel off any intermediate conversions-to-pointer for valid
4640 pointer modes. */
4641 while (TREE_CODE (exp) == NOP_EXPR
4642 && POINTER_TYPE_P (TREE_TYPE (exp))
4643 && targetm.addr_space.valid_pointer_mode
4644 (TYPE_MODE (TREE_TYPE (exp)),
4645 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4646 exp = TREE_OPERAND (exp, 0);
4647
4648 /* If what we're left with is the address of something, we can
4649 convert the address to the final type and output it that
4650 way. */
4651 if (TREE_CODE (exp) == ADDR_EXPR)
4652 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4653 /* Likewise for constant ints. */
4654 else if (TREE_CODE (exp) == INTEGER_CST)
4655 exp = wide_int_to_tree (saved_type, exp);
4656
4657 }
4658
4659 /* Eliminate any conversions since we'll be outputting the underlying
4660 constant. */
4661 while (CONVERT_EXPR_P (exp)
4662 || TREE_CODE (exp) == NON_LVALUE_EXPR
4663 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4664 {
4665 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4666 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4667
4668 /* Make sure eliminating the conversion is really a no-op, except with
4669 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4670 union types to allow for Ada unchecked unions. */
4671 if (type_size > op_size
4672 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4673 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4674 /* Keep the conversion. */
4675 break;
4676 else
4677 exp = TREE_OPERAND (exp, 0);
4678 }
4679
4680 code = TREE_CODE (TREE_TYPE (exp));
4681 thissize = int_size_in_bytes (TREE_TYPE (exp));
4682
4683 /* Allow a constructor with no elements for any data type.
4684 This means to fill the space with zeros. */
4685 if (TREE_CODE (exp) == CONSTRUCTOR
4686 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4687 {
4688 assemble_zeros (size);
4689 return;
4690 }
4691
4692 if (TREE_CODE (exp) == FDESC_EXPR)
4693 {
4694 #ifdef ASM_OUTPUT_FDESC
4695 HOST_WIDE_INT part = tree_to_shwi (TREE_OPERAND (exp, 1));
4696 tree decl = TREE_OPERAND (exp, 0);
4697 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4698 #else
4699 gcc_unreachable ();
4700 #endif
4701 return;
4702 }
4703
4704 /* Now output the underlying data. If we've handling the padding, return.
4705 Otherwise, break and ensure SIZE is the size written. */
4706 switch (code)
4707 {
4708 case BOOLEAN_TYPE:
4709 case INTEGER_TYPE:
4710 case ENUMERAL_TYPE:
4711 case POINTER_TYPE:
4712 case REFERENCE_TYPE:
4713 case OFFSET_TYPE:
4714 case FIXED_POINT_TYPE:
4715 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
4716 EXPAND_INITIALIZER),
4717 MIN (size, thissize), align, 0))
4718 error ("initializer for integer/fixed-point value is too complicated");
4719 break;
4720
4721 case REAL_TYPE:
4722 if (TREE_CODE (exp) != REAL_CST)
4723 error ("initializer for floating value is not a floating constant");
4724 else
4725 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)), align);
4726 break;
4727
4728 case COMPLEX_TYPE:
4729 output_constant (TREE_REALPART (exp), thissize / 2, align);
4730 output_constant (TREE_IMAGPART (exp), thissize / 2,
4731 min_align (align, BITS_PER_UNIT * (thissize / 2)));
4732 break;
4733
4734 case ARRAY_TYPE:
4735 case VECTOR_TYPE:
4736 switch (TREE_CODE (exp))
4737 {
4738 case CONSTRUCTOR:
4739 output_constructor (exp, size, align, NULL);
4740 return;
4741 case STRING_CST:
4742 thissize
4743 = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4744 assemble_string (TREE_STRING_POINTER (exp), thissize);
4745 break;
4746 case VECTOR_CST:
4747 {
4748 enum machine_mode inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4749 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4750 int elt_size = GET_MODE_SIZE (inner);
4751 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align);
4752 thissize = elt_size;
4753 for (unsigned int i = 1; i < VECTOR_CST_NELTS (exp); i++)
4754 {
4755 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign);
4756 thissize += elt_size;
4757 }
4758 break;
4759 }
4760 default:
4761 gcc_unreachable ();
4762 }
4763 break;
4764
4765 case RECORD_TYPE:
4766 case UNION_TYPE:
4767 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4768 output_constructor (exp, size, align, NULL);
4769 return;
4770
4771 case ERROR_MARK:
4772 return;
4773
4774 default:
4775 gcc_unreachable ();
4776 }
4777
4778 if (size > thissize)
4779 assemble_zeros (size - thissize);
4780 }
4781
4782 \f
4783 /* Subroutine of output_constructor, used for computing the size of
4784 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4785 type with an unspecified upper bound. */
4786
4787 static unsigned HOST_WIDE_INT
4788 array_size_for_constructor (tree val)
4789 {
4790 tree max_index;
4791 unsigned HOST_WIDE_INT cnt;
4792 tree index, value, tmp;
4793 addr_wide_int i;
4794
4795 /* This code used to attempt to handle string constants that are not
4796 arrays of single-bytes, but nothing else does, so there's no point in
4797 doing it here. */
4798 if (TREE_CODE (val) == STRING_CST)
4799 return TREE_STRING_LENGTH (val);
4800
4801 max_index = NULL_TREE;
4802 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
4803 {
4804 if (TREE_CODE (index) == RANGE_EXPR)
4805 index = TREE_OPERAND (index, 1);
4806 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
4807 max_index = index;
4808 }
4809
4810 if (max_index == NULL_TREE)
4811 return 0;
4812
4813 /* Compute the total number of array elements. */
4814 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
4815 i = addr_wide_int (max_index) - tmp + 1;
4816
4817 /* Multiply by the array element unit size to find number of bytes. */
4818 i *= addr_wide_int (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
4819
4820 gcc_assert (wi::fits_uhwi_p (i));
4821 return i.to_uhwi ();
4822 }
4823
4824 /* Other datastructures + helpers for output_constructor. */
4825
4826 /* output_constructor local state to support interaction with helpers. */
4827
4828 typedef struct {
4829
4830 /* Received arguments. */
4831 tree exp; /* Constructor expression. */
4832 tree type; /* Type of constructor expression. */
4833 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */
4834 unsigned int align; /* Known initial alignment. */
4835 tree min_index; /* Lower bound if specified for an array. */
4836
4837 /* Output processing state. */
4838 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */
4839 int byte; /* Part of a bitfield byte yet to be output. */
4840 int last_relative_index; /* Implicit or explicit index of the last
4841 array element output within a bitfield. */
4842 bool byte_buffer_in_use; /* Whether BYTE is in use. */
4843
4844 /* Current element. */
4845 tree field; /* Current field decl in a record. */
4846 tree val; /* Current element value. */
4847 tree index; /* Current element index. */
4848
4849 } oc_local_state;
4850
4851 /* Helper for output_constructor. From the current LOCAL state, output a
4852 RANGE_EXPR element. */
4853
4854 static void
4855 output_constructor_array_range (oc_local_state *local)
4856 {
4857 unsigned HOST_WIDE_INT fieldsize
4858 = int_size_in_bytes (TREE_TYPE (local->type));
4859
4860 HOST_WIDE_INT lo_index
4861 = tree_to_shwi (TREE_OPERAND (local->index, 0));
4862 HOST_WIDE_INT hi_index
4863 = tree_to_shwi (TREE_OPERAND (local->index, 1));
4864 HOST_WIDE_INT index;
4865
4866 unsigned int align2
4867 = min_align (local->align, fieldsize * BITS_PER_UNIT);
4868
4869 for (index = lo_index; index <= hi_index; index++)
4870 {
4871 /* Output the element's initial value. */
4872 if (local->val == NULL_TREE)
4873 assemble_zeros (fieldsize);
4874 else
4875 output_constant (local->val, fieldsize, align2);
4876
4877 /* Count its size. */
4878 local->total_bytes += fieldsize;
4879 }
4880 }
4881
4882 /* Helper for output_constructor. From the current LOCAL state, output a
4883 field element that is not true bitfield or part of an outer one. */
4884
4885 static void
4886 output_constructor_regular_field (oc_local_state *local)
4887 {
4888 /* Field size and position. Since this structure is static, we know the
4889 positions are constant. */
4890 unsigned HOST_WIDE_INT fieldsize;
4891 HOST_WIDE_INT fieldpos;
4892
4893 unsigned int align2;
4894
4895 if (local->index != NULL_TREE)
4896 {
4897 /* Perform the index calculation in modulo arithmetic but
4898 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
4899 but we are using an unsigned sizetype. */
4900 unsigned prec = TYPE_PRECISION (sizetype);
4901 addr_wide_int idx
4902 = wi::sext (addr_wide_int (local->index) - local->min_index, prec);
4903 fieldpos = (idx * TYPE_SIZE_UNIT (TREE_TYPE (local->val))).to_shwi ();
4904 }
4905 else if (local->field != NULL_TREE)
4906 fieldpos = int_byte_position (local->field);
4907 else
4908 fieldpos = 0;
4909
4910 /* Output any buffered-up bit-fields preceding this element. */
4911 if (local->byte_buffer_in_use)
4912 {
4913 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4914 local->total_bytes++;
4915 local->byte_buffer_in_use = false;
4916 }
4917
4918 /* Advance to offset of this element.
4919 Note no alignment needed in an array, since that is guaranteed
4920 if each element has the proper size. */
4921 if ((local->field != NULL_TREE || local->index != NULL_TREE)
4922 && fieldpos != local->total_bytes)
4923 {
4924 gcc_assert (fieldpos >= local->total_bytes);
4925 assemble_zeros (fieldpos - local->total_bytes);
4926 local->total_bytes = fieldpos;
4927 }
4928
4929 /* Find the alignment of this element. */
4930 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
4931
4932 /* Determine size this element should occupy. */
4933 if (local->field)
4934 {
4935 fieldsize = 0;
4936
4937 /* If this is an array with an unspecified upper bound,
4938 the initializer determines the size. */
4939 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
4940 but we cannot do this until the deprecated support for
4941 initializing zero-length array members is removed. */
4942 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
4943 && TYPE_DOMAIN (TREE_TYPE (local->field))
4944 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field))))
4945 {
4946 fieldsize = array_size_for_constructor (local->val);
4947 /* Given a non-empty initialization, this field had
4948 better be last. */
4949 gcc_assert (!fieldsize || !DECL_CHAIN (local->field));
4950 }
4951 else
4952 fieldsize = tree_to_uhwi (DECL_SIZE_UNIT (local->field));
4953 }
4954 else
4955 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
4956
4957 /* Output the element's initial value. */
4958 if (local->val == NULL_TREE)
4959 assemble_zeros (fieldsize);
4960 else
4961 output_constant (local->val, fieldsize, align2);
4962
4963 /* Count its size. */
4964 local->total_bytes += fieldsize;
4965 }
4966
4967 /* Helper for output_constructor. From the LOCAL state, output an element
4968 that is a true bitfield or part of an outer one. BIT_OFFSET is the offset
4969 from the start of a possibly ongoing outer byte buffer. */
4970
4971 static void
4972 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
4973 {
4974 /* Bit size of this element. */
4975 HOST_WIDE_INT ebitsize
4976 = (local->field
4977 ? tree_to_uhwi (DECL_SIZE (local->field))
4978 : tree_to_uhwi (TYPE_SIZE (TREE_TYPE (local->type))));
4979
4980 /* Relative index of this element if this is an array component. */
4981 HOST_WIDE_INT relative_index
4982 = (!local->field
4983 ? (local->index
4984 ? (tree_to_shwi (local->index)
4985 - tree_to_shwi (local->min_index))
4986 : local->last_relative_index + 1)
4987 : 0);
4988
4989 /* Bit position of this element from the start of the containing
4990 constructor. */
4991 HOST_WIDE_INT constructor_relative_ebitpos
4992 = (local->field
4993 ? int_bit_position (local->field)
4994 : ebitsize * relative_index);
4995
4996 /* Bit position of this element from the start of a possibly ongoing
4997 outer byte buffer. */
4998 HOST_WIDE_INT byte_relative_ebitpos
4999 = bit_offset + constructor_relative_ebitpos;
5000
5001 /* From the start of a possibly ongoing outer byte buffer, offsets to
5002 the first bit of this element and to the first bit past the end of
5003 this element. */
5004 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
5005 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
5006
5007 local->last_relative_index = relative_index;
5008
5009 if (local->val == NULL_TREE)
5010 local->val = integer_zero_node;
5011
5012 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
5013 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
5014 local->val = TREE_OPERAND (local->val, 0);
5015
5016 if (TREE_CODE (local->val) != INTEGER_CST
5017 && TREE_CODE (local->val) != CONSTRUCTOR)
5018 {
5019 error ("invalid initial value for member %qE", DECL_NAME (local->field));
5020 return;
5021 }
5022
5023 /* If this field does not start in this (or next) byte, skip some bytes. */
5024 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5025 {
5026 /* Output remnant of any bit field in previous bytes. */
5027 if (local->byte_buffer_in_use)
5028 {
5029 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5030 local->total_bytes++;
5031 local->byte_buffer_in_use = false;
5032 }
5033
5034 /* If still not at proper byte, advance to there. */
5035 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5036 {
5037 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
5038 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
5039 local->total_bytes = next_offset / BITS_PER_UNIT;
5040 }
5041 }
5042
5043 /* Set up the buffer if necessary. */
5044 if (!local->byte_buffer_in_use)
5045 {
5046 local->byte = 0;
5047 if (ebitsize > 0)
5048 local->byte_buffer_in_use = true;
5049 }
5050
5051 /* If this is nested constructor, recurse passing the bit offset and the
5052 pending data, then retrieve the new pending data afterwards. */
5053 if (TREE_CODE (local->val) == CONSTRUCTOR)
5054 {
5055 oc_outer_state temp_state;
5056 temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5057 temp_state.byte = local->byte;
5058 local->total_bytes
5059 += output_constructor (local->val, 0, 0, &temp_state);
5060 local->byte = temp_state.byte;
5061 return;
5062 }
5063
5064 /* Otherwise, we must split the element into pieces that fall within
5065 separate bytes, and combine each byte with previous or following
5066 bit-fields. */
5067 while (next_offset < end_offset)
5068 {
5069 int this_time;
5070 int shift;
5071 HOST_WIDE_INT value;
5072 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5073 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5074
5075 /* Advance from byte to byte within this element when necessary. */
5076 while (next_byte != local->total_bytes)
5077 {
5078 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5079 local->total_bytes++;
5080 local->byte = 0;
5081 }
5082
5083 /* Number of bits we can process at once (all part of the same byte). */
5084 this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5085 if (BYTES_BIG_ENDIAN)
5086 {
5087 /* On big-endian machine, take the most significant bits
5088 first (of the bits that are significant)
5089 and put them into bytes from the most significant end. */
5090 shift = end_offset - next_offset - this_time;
5091
5092 /* Don't try to take a bunch of bits that cross
5093 the word boundary in the INTEGER_CST. We can
5094 only select bits from the LOW or HIGH part
5095 not from both. */
5096 if ((shift / HOST_BITS_PER_WIDE_INT)
5097 != ((shift + this_time) / HOST_BITS_PER_WIDE_INT))
5098 this_time = (shift + this_time) & (HOST_BITS_PER_WIDE_INT - 1);
5099
5100 /* Now get the bits from the appropriate constant word. */
5101 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5102 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5103
5104 /* Get the result. This works only when:
5105 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5106 local->byte |= (((value >> shift)
5107 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5108 << (BITS_PER_UNIT - this_time - next_bit));
5109 }
5110 else
5111 {
5112 /* On little-endian machines,
5113 take first the least significant bits of the value
5114 and pack them starting at the least significant
5115 bits of the bytes. */
5116 shift = next_offset - byte_relative_ebitpos;
5117
5118 /* Don't try to take a bunch of bits that cross
5119 the word boundary in the INTEGER_CST. We can
5120 only select bits from the LOW or HIGH part
5121 not from both. */
5122 if ((shift / HOST_BITS_PER_WIDE_INT)
5123 != ((shift + this_time) / HOST_BITS_PER_WIDE_INT))
5124 this_time = (HOST_BITS_PER_WIDE_INT - shift);
5125
5126 /* Now get the bits from the appropriate constant word. */
5127 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5128 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5129
5130 /* Get the result. This works only when:
5131 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5132 local->byte |= (((value >> shift)
5133 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5134 << next_bit);
5135 }
5136
5137 next_offset += this_time;
5138 local->byte_buffer_in_use = true;
5139 }
5140 }
5141
5142 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5143 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5144 caller output state of relevance in recursive invocations. */
5145
5146 static unsigned HOST_WIDE_INT
5147 output_constructor (tree exp, unsigned HOST_WIDE_INT size,
5148 unsigned int align, oc_outer_state *outer)
5149 {
5150 unsigned HOST_WIDE_INT cnt;
5151 constructor_elt *ce;
5152
5153 oc_local_state local;
5154
5155 /* Setup our local state to communicate with helpers. */
5156 local.exp = exp;
5157 local.type = TREE_TYPE (exp);
5158 local.size = size;
5159 local.align = align;
5160 if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5161 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5162 else
5163 local.min_index = NULL_TREE;
5164
5165 local.total_bytes = 0;
5166 local.byte_buffer_in_use = outer != NULL;
5167 local.byte = outer ? outer->byte : 0;
5168 local.last_relative_index = -1;
5169
5170 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5171
5172 /* As CE goes through the elements of the constant, FIELD goes through the
5173 structure fields if the constant is a structure. If the constant is a
5174 union, we override this by getting the field from the TREE_LIST element.
5175 But the constant could also be an array. Then FIELD is zero.
5176
5177 There is always a maximum of one element in the chain LINK for unions
5178 (even if the initializer in a source program incorrectly contains
5179 more one). */
5180
5181 if (TREE_CODE (local.type) == RECORD_TYPE)
5182 local.field = TYPE_FIELDS (local.type);
5183 else
5184 local.field = NULL_TREE;
5185
5186 for (cnt = 0;
5187 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5188 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5189 {
5190 local.val = ce->value;
5191 local.index = NULL_TREE;
5192
5193 /* The element in a union constructor specifies the proper field
5194 or index. */
5195 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5196 local.field = ce->index;
5197
5198 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5199 local.index = ce->index;
5200
5201 if (local.field && flag_verbose_asm)
5202 fprintf (asm_out_file, "%s %s:\n",
5203 ASM_COMMENT_START,
5204 DECL_NAME (local.field)
5205 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5206 : "<anonymous>");
5207
5208 /* Eliminate the marker that makes a cast not be an lvalue. */
5209 if (local.val != NULL_TREE)
5210 STRIP_NOPS (local.val);
5211
5212 /* Output the current element, using the appropriate helper ... */
5213
5214 /* For an array slice not part of an outer bitfield. */
5215 if (!outer
5216 && local.index != NULL_TREE
5217 && TREE_CODE (local.index) == RANGE_EXPR)
5218 output_constructor_array_range (&local);
5219
5220 /* For a field that is neither a true bitfield nor part of an outer one,
5221 known to be at least byte aligned and multiple-of-bytes long. */
5222 else if (!outer
5223 && (local.field == NULL_TREE
5224 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5225 output_constructor_regular_field (&local);
5226
5227 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5228 supported for scalar fields, so we may need to convert first. */
5229 else
5230 {
5231 if (TREE_CODE (local.val) == REAL_CST)
5232 local.val
5233 = fold_unary (VIEW_CONVERT_EXPR,
5234 build_nonstandard_integer_type
5235 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5236 local.val);
5237 output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5238 }
5239 }
5240
5241 /* If we are not at toplevel, save the pending data for our caller.
5242 Otherwise output the pending data and padding zeros as needed. */
5243 if (outer)
5244 outer->byte = local.byte;
5245 else
5246 {
5247 if (local.byte_buffer_in_use)
5248 {
5249 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5250 local.total_bytes++;
5251 }
5252
5253 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5254 {
5255 assemble_zeros (local.size - local.total_bytes);
5256 local.total_bytes = local.size;
5257 }
5258 }
5259
5260 return local.total_bytes;
5261 }
5262
5263 /* Mark DECL as weak. */
5264
5265 static void
5266 mark_weak (tree decl)
5267 {
5268 DECL_WEAK (decl) = 1;
5269
5270 if (DECL_RTL_SET_P (decl)
5271 && MEM_P (DECL_RTL (decl))
5272 && XEXP (DECL_RTL (decl), 0)
5273 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5274 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5275 }
5276
5277 /* Merge weak status between NEWDECL and OLDDECL. */
5278
5279 void
5280 merge_weak (tree newdecl, tree olddecl)
5281 {
5282 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5283 {
5284 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5285 {
5286 tree *pwd;
5287 /* We put the NEWDECL on the weak_decls list at some point
5288 and OLDDECL as well. Keep just OLDDECL on the list. */
5289 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5290 if (TREE_VALUE (*pwd) == newdecl)
5291 {
5292 *pwd = TREE_CHAIN (*pwd);
5293 break;
5294 }
5295 }
5296 return;
5297 }
5298
5299 if (DECL_WEAK (newdecl))
5300 {
5301 tree wd;
5302
5303 /* NEWDECL is weak, but OLDDECL is not. */
5304
5305 /* If we already output the OLDDECL, we're in trouble; we can't
5306 go back and make it weak. This should never happen in
5307 unit-at-a-time compilation. */
5308 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5309
5310 /* If we've already generated rtl referencing OLDDECL, we may
5311 have done so in a way that will not function properly with
5312 a weak symbol. Again in unit-at-a-time this should be
5313 impossible. */
5314 gcc_assert (!TREE_USED (olddecl)
5315 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5316
5317 if (TARGET_SUPPORTS_WEAK)
5318 {
5319 /* We put the NEWDECL on the weak_decls list at some point.
5320 Replace it with the OLDDECL. */
5321 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5322 if (TREE_VALUE (wd) == newdecl)
5323 {
5324 TREE_VALUE (wd) = olddecl;
5325 break;
5326 }
5327 /* We may not find the entry on the list. If NEWDECL is a
5328 weak alias, then we will have already called
5329 globalize_decl to remove the entry; in that case, we do
5330 not need to do anything. */
5331 }
5332
5333 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5334 mark_weak (olddecl);
5335 }
5336 else
5337 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5338 weak. Just update NEWDECL to indicate that it's weak too. */
5339 mark_weak (newdecl);
5340 }
5341
5342 /* Declare DECL to be a weak symbol. */
5343
5344 void
5345 declare_weak (tree decl)
5346 {
5347 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5348 if (! TREE_PUBLIC (decl))
5349 error ("weak declaration of %q+D must be public", decl);
5350 else if (!TARGET_SUPPORTS_WEAK)
5351 warning (0, "weak declaration of %q+D not supported", decl);
5352
5353 mark_weak (decl);
5354 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5355 DECL_ATTRIBUTES (decl)
5356 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5357 }
5358
5359 static void
5360 weak_finish_1 (tree decl)
5361 {
5362 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5363 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5364 #endif
5365
5366 if (! TREE_USED (decl))
5367 return;
5368
5369 #ifdef ASM_WEAKEN_DECL
5370 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5371 #else
5372 #ifdef ASM_WEAKEN_LABEL
5373 ASM_WEAKEN_LABEL (asm_out_file, name);
5374 #else
5375 #ifdef ASM_OUTPUT_WEAK_ALIAS
5376 {
5377 static bool warn_once = 0;
5378 if (! warn_once)
5379 {
5380 warning (0, "only weak aliases are supported in this configuration");
5381 warn_once = 1;
5382 }
5383 return;
5384 }
5385 #endif
5386 #endif
5387 #endif
5388 }
5389
5390 /* Fiven an assembly name, find the decl it is associated with. */
5391 static tree
5392 find_decl (tree target)
5393 {
5394 symtab_node node = symtab_node_for_asm (target);
5395 if (node)
5396 return node->symbol.decl;
5397 return NULL_TREE;
5398 }
5399
5400 /* This TREE_LIST contains weakref targets. */
5401
5402 static GTY(()) tree weakref_targets;
5403
5404 /* Emit any pending weak declarations. */
5405
5406 void
5407 weak_finish (void)
5408 {
5409 tree t;
5410
5411 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5412 {
5413 tree alias_decl = TREE_PURPOSE (t);
5414 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5415
5416 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5417 /* Remove alias_decl from the weak list, but leave entries for
5418 the target alone. */
5419 target = NULL_TREE;
5420 #ifndef ASM_OUTPUT_WEAKREF
5421 else if (! TREE_SYMBOL_REFERENCED (target))
5422 {
5423 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5424 defined, otherwise we and weak_finish_1 would use
5425 different macros. */
5426 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5427 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5428 # else
5429 tree decl = find_decl (target);
5430
5431 if (! decl)
5432 {
5433 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5434 TREE_CODE (alias_decl), target,
5435 TREE_TYPE (alias_decl));
5436
5437 DECL_EXTERNAL (decl) = 1;
5438 TREE_PUBLIC (decl) = 1;
5439 DECL_ARTIFICIAL (decl) = 1;
5440 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5441 TREE_USED (decl) = 1;
5442 }
5443
5444 weak_finish_1 (decl);
5445 # endif
5446 }
5447 #endif
5448
5449 {
5450 tree *p;
5451 tree t2;
5452
5453 /* Remove the alias and the target from the pending weak list
5454 so that we do not emit any .weak directives for the former,
5455 nor multiple .weak directives for the latter. */
5456 for (p = &weak_decls; (t2 = *p) ; )
5457 {
5458 if (TREE_VALUE (t2) == alias_decl
5459 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5460 *p = TREE_CHAIN (t2);
5461 else
5462 p = &TREE_CHAIN (t2);
5463 }
5464
5465 /* Remove other weakrefs to the same target, to speed things up. */
5466 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5467 {
5468 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5469 *p = TREE_CHAIN (t2);
5470 else
5471 p = &TREE_CHAIN (t2);
5472 }
5473 }
5474 }
5475
5476 for (t = weak_decls; t; t = TREE_CHAIN (t))
5477 {
5478 tree decl = TREE_VALUE (t);
5479
5480 weak_finish_1 (decl);
5481 }
5482 }
5483
5484 /* Emit the assembly bits to indicate that DECL is globally visible. */
5485
5486 static void
5487 globalize_decl (tree decl)
5488 {
5489
5490 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5491 if (DECL_WEAK (decl))
5492 {
5493 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5494 tree *p, t;
5495
5496 #ifdef ASM_WEAKEN_DECL
5497 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5498 #else
5499 ASM_WEAKEN_LABEL (asm_out_file, name);
5500 #endif
5501
5502 /* Remove this function from the pending weak list so that
5503 we do not emit multiple .weak directives for it. */
5504 for (p = &weak_decls; (t = *p) ; )
5505 {
5506 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5507 *p = TREE_CHAIN (t);
5508 else
5509 p = &TREE_CHAIN (t);
5510 }
5511
5512 /* Remove weakrefs to the same target from the pending weakref
5513 list, for the same reason. */
5514 for (p = &weakref_targets; (t = *p) ; )
5515 {
5516 if (DECL_ASSEMBLER_NAME (decl)
5517 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5518 *p = TREE_CHAIN (t);
5519 else
5520 p = &TREE_CHAIN (t);
5521 }
5522
5523 return;
5524 }
5525 #endif
5526
5527 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5528 }
5529
5530 vec<alias_pair, va_gc> *alias_pairs;
5531
5532 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5533 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5534 tree node is DECL to have the value of the tree node TARGET. */
5535
5536 void
5537 do_assemble_alias (tree decl, tree target)
5538 {
5539 /* Emulated TLS had better not get this var. */
5540 gcc_assert (!(!targetm.have_tls
5541 && TREE_CODE (decl) == VAR_DECL
5542 && DECL_THREAD_LOCAL_P (decl)));
5543
5544 if (TREE_ASM_WRITTEN (decl))
5545 return;
5546
5547 /* We must force creation of DECL_RTL for debug info generation, even though
5548 we don't use it here. */
5549 make_decl_rtl (decl);
5550
5551 TREE_ASM_WRITTEN (decl) = 1;
5552 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5553
5554 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5555 {
5556 ultimate_transparent_alias_target (&target);
5557
5558 if (!TREE_SYMBOL_REFERENCED (target))
5559 weakref_targets = tree_cons (decl, target, weakref_targets);
5560
5561 #ifdef ASM_OUTPUT_WEAKREF
5562 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5563 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5564 IDENTIFIER_POINTER (target));
5565 #else
5566 if (!TARGET_SUPPORTS_WEAK)
5567 {
5568 error_at (DECL_SOURCE_LOCATION (decl),
5569 "weakref is not supported in this configuration");
5570 return;
5571 }
5572 #endif
5573 return;
5574 }
5575
5576 #ifdef ASM_OUTPUT_DEF
5577 /* Make name accessible from other files, if appropriate. */
5578
5579 if (TREE_PUBLIC (decl))
5580 {
5581 globalize_decl (decl);
5582 maybe_assemble_visibility (decl);
5583 }
5584 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5585 {
5586 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5587 if (targetm.has_ifunc_p ())
5588 ASM_OUTPUT_TYPE_DIRECTIVE
5589 (asm_out_file, IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5590 IFUNC_ASM_TYPE);
5591 else
5592 #endif
5593 error_at (DECL_SOURCE_LOCATION (decl),
5594 "ifunc is not supported on this target");
5595 }
5596
5597 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5598 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5599 # else
5600 ASM_OUTPUT_DEF (asm_out_file,
5601 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5602 IDENTIFIER_POINTER (target));
5603 # endif
5604 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5605 {
5606 const char *name;
5607 tree *p, t;
5608
5609 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5610 # ifdef ASM_WEAKEN_DECL
5611 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5612 # else
5613 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5614 # endif
5615 /* Remove this function from the pending weak list so that
5616 we do not emit multiple .weak directives for it. */
5617 for (p = &weak_decls; (t = *p) ; )
5618 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5619 *p = TREE_CHAIN (t);
5620 else
5621 p = &TREE_CHAIN (t);
5622
5623 /* Remove weakrefs to the same target from the pending weakref
5624 list, for the same reason. */
5625 for (p = &weakref_targets; (t = *p) ; )
5626 {
5627 if (DECL_ASSEMBLER_NAME (decl)
5628 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5629 *p = TREE_CHAIN (t);
5630 else
5631 p = &TREE_CHAIN (t);
5632 }
5633 }
5634 #endif
5635 }
5636
5637 /* Emit an assembler directive to make the symbol for DECL an alias to
5638 the symbol for TARGET. */
5639
5640 void
5641 assemble_alias (tree decl, tree target)
5642 {
5643 tree target_decl;
5644
5645 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5646 {
5647 tree alias = DECL_ASSEMBLER_NAME (decl);
5648
5649 ultimate_transparent_alias_target (&target);
5650
5651 if (alias == target)
5652 error ("weakref %q+D ultimately targets itself", decl);
5653 if (TREE_PUBLIC (decl))
5654 error ("weakref %q+D must have static linkage", decl);
5655 }
5656 else
5657 {
5658 #if !defined (ASM_OUTPUT_DEF)
5659 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5660 error_at (DECL_SOURCE_LOCATION (decl),
5661 "alias definitions not supported in this configuration");
5662 return;
5663 # else
5664 if (!DECL_WEAK (decl))
5665 {
5666 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5667 error_at (DECL_SOURCE_LOCATION (decl),
5668 "ifunc is not supported in this configuration");
5669 else
5670 error_at (DECL_SOURCE_LOCATION (decl),
5671 "only weak aliases are supported in this configuration");
5672 return;
5673 }
5674 # endif
5675 #endif
5676 }
5677 TREE_USED (decl) = 1;
5678
5679 /* Allow aliases to aliases. */
5680 if (TREE_CODE (decl) == FUNCTION_DECL)
5681 cgraph_get_create_node (decl)->symbol.alias = true;
5682 else
5683 varpool_node_for_decl (decl)->symbol.alias = true;
5684
5685 /* If the target has already been emitted, we don't have to queue the
5686 alias. This saves a tad of memory. */
5687 if (cgraph_global_info_ready)
5688 target_decl = find_decl (target);
5689 else
5690 target_decl= NULL;
5691 if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5692 || cgraph_state >= CGRAPH_STATE_EXPANSION)
5693 do_assemble_alias (decl, target);
5694 else
5695 {
5696 alias_pair p = {decl, target};
5697 vec_safe_push (alias_pairs, p);
5698 }
5699 }
5700
5701 /* Record and output a table of translations from original function
5702 to its transaction aware clone. Note that tm_pure functions are
5703 considered to be their own clone. */
5704
5705 static GTY((if_marked ("tree_map_marked_p"), param_is (struct tree_map)))
5706 htab_t tm_clone_hash;
5707
5708 void
5709 record_tm_clone_pair (tree o, tree n)
5710 {
5711 struct tree_map **slot, *h;
5712
5713 if (tm_clone_hash == NULL)
5714 tm_clone_hash = htab_create_ggc (32, tree_map_hash, tree_map_eq, 0);
5715
5716 h = ggc_alloc_tree_map ();
5717 h->hash = htab_hash_pointer (o);
5718 h->base.from = o;
5719 h->to = n;
5720
5721 slot = (struct tree_map **)
5722 htab_find_slot_with_hash (tm_clone_hash, h, h->hash, INSERT);
5723 *slot = h;
5724 }
5725
5726 tree
5727 get_tm_clone_pair (tree o)
5728 {
5729 if (tm_clone_hash)
5730 {
5731 struct tree_map *h, in;
5732
5733 in.base.from = o;
5734 in.hash = htab_hash_pointer (o);
5735 h = (struct tree_map *) htab_find_with_hash (tm_clone_hash,
5736 &in, in.hash);
5737 if (h)
5738 return h->to;
5739 }
5740 return NULL_TREE;
5741 }
5742
5743 typedef struct tm_alias_pair
5744 {
5745 unsigned int uid;
5746 tree from;
5747 tree to;
5748 } tm_alias_pair;
5749
5750
5751 /* Helper function for finish_tm_clone_pairs. Dump a hash table entry
5752 into a VEC in INFO. */
5753
5754 static int
5755 dump_tm_clone_to_vec (void **slot, void *info)
5756 {
5757 struct tree_map *map = (struct tree_map *) *slot;
5758 vec<tm_alias_pair> *tm_alias_pairs = (vec<tm_alias_pair> *) info;
5759 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
5760 tm_alias_pairs->safe_push (p);
5761 return 1;
5762 }
5763
5764 /* Dump the actual pairs to the .tm_clone_table section. */
5765
5766 static void
5767 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
5768 {
5769 unsigned i;
5770 tm_alias_pair *p;
5771 bool switched = false;
5772
5773 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
5774 {
5775 tree src = p->from;
5776 tree dst = p->to;
5777 struct cgraph_node *src_n = cgraph_get_node (src);
5778 struct cgraph_node *dst_n = cgraph_get_node (dst);
5779
5780 /* The function ipa_tm_create_version() marks the clone as needed if
5781 the original function was needed. But we also mark the clone as
5782 needed if we ever called the clone indirectly through
5783 TM_GETTMCLONE. If neither of these are true, we didn't generate
5784 a clone, and we didn't call it indirectly... no sense keeping it
5785 in the clone table. */
5786 if (!dst_n || !dst_n->symbol.definition)
5787 continue;
5788
5789 /* This covers the case where we have optimized the original
5790 function away, and only access the transactional clone. */
5791 if (!src_n || !src_n->symbol.definition)
5792 continue;
5793
5794 if (!switched)
5795 {
5796 switch_to_section (targetm.asm_out.tm_clone_table_section ());
5797 assemble_align (POINTER_SIZE);
5798 switched = true;
5799 }
5800
5801 assemble_integer (XEXP (DECL_RTL (src), 0),
5802 POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
5803 assemble_integer (XEXP (DECL_RTL (dst), 0),
5804 POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
5805 }
5806 }
5807
5808 /* Provide a default for the tm_clone_table section. */
5809
5810 section *
5811 default_clone_table_section (void)
5812 {
5813 return get_named_section (NULL, ".tm_clone_table", 3);
5814 }
5815
5816 /* Helper comparison function for qsorting by the DECL_UID stored in
5817 alias_pair->emitted_diags. */
5818
5819 static int
5820 tm_alias_pair_cmp (const void *x, const void *y)
5821 {
5822 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
5823 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
5824 if (p1->uid < p2->uid)
5825 return -1;
5826 if (p1->uid > p2->uid)
5827 return 1;
5828 return 0;
5829 }
5830
5831 void
5832 finish_tm_clone_pairs (void)
5833 {
5834 vec<tm_alias_pair> tm_alias_pairs = vNULL;
5835
5836 if (tm_clone_hash == NULL)
5837 return;
5838
5839 /* We need a determenistic order for the .tm_clone_table, otherwise
5840 we will get bootstrap comparison failures, so dump the hash table
5841 to a vector, sort it, and dump the vector. */
5842
5843 /* Dump the hashtable to a vector. */
5844 htab_traverse_noresize (tm_clone_hash, dump_tm_clone_to_vec,
5845 (void *) &tm_alias_pairs);
5846 /* Sort it. */
5847 tm_alias_pairs.qsort (tm_alias_pair_cmp);
5848
5849 /* Dump it. */
5850 dump_tm_clone_pairs (tm_alias_pairs);
5851
5852 htab_delete (tm_clone_hash);
5853 tm_clone_hash = NULL;
5854 tm_alias_pairs.release ();
5855 }
5856
5857
5858 /* Emit an assembler directive to set symbol for DECL visibility to
5859 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
5860
5861 void
5862 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
5863 int vis ATTRIBUTE_UNUSED)
5864 {
5865 #ifdef HAVE_GAS_HIDDEN
5866 static const char * const visibility_types[] = {
5867 NULL, "protected", "hidden", "internal"
5868 };
5869
5870 const char *name, *type;
5871
5872 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5873 type = visibility_types[vis];
5874
5875 fprintf (asm_out_file, "\t.%s\t", type);
5876 assemble_name (asm_out_file, name);
5877 fprintf (asm_out_file, "\n");
5878 #else
5879 if (!DECL_ARTIFICIAL (decl))
5880 warning (OPT_Wattributes, "visibility attribute not supported "
5881 "in this configuration; ignored");
5882 #endif
5883 }
5884
5885 /* A helper function to call assemble_visibility when needed for a decl. */
5886
5887 int
5888 maybe_assemble_visibility (tree decl)
5889 {
5890 enum symbol_visibility vis = DECL_VISIBILITY (decl);
5891
5892 if (vis != VISIBILITY_DEFAULT)
5893 {
5894 targetm.asm_out.assemble_visibility (decl, vis);
5895 return 1;
5896 }
5897 else
5898 return 0;
5899 }
5900
5901 /* Returns 1 if the target configuration supports defining public symbols
5902 so that one of them will be chosen at link time instead of generating a
5903 multiply-defined symbol error, whether through the use of weak symbols or
5904 a target-specific mechanism for having duplicates discarded. */
5905
5906 int
5907 supports_one_only (void)
5908 {
5909 if (SUPPORTS_ONE_ONLY)
5910 return 1;
5911 return TARGET_SUPPORTS_WEAK;
5912 }
5913
5914 /* Set up DECL as a public symbol that can be defined in multiple
5915 translation units without generating a linker error. */
5916
5917 void
5918 make_decl_one_only (tree decl, tree comdat_group)
5919 {
5920 gcc_assert (TREE_CODE (decl) == VAR_DECL
5921 || TREE_CODE (decl) == FUNCTION_DECL);
5922
5923 TREE_PUBLIC (decl) = 1;
5924
5925 if (SUPPORTS_ONE_ONLY)
5926 {
5927 #ifdef MAKE_DECL_ONE_ONLY
5928 MAKE_DECL_ONE_ONLY (decl);
5929 #endif
5930 DECL_COMDAT_GROUP (decl) = comdat_group;
5931 }
5932 else if (TREE_CODE (decl) == VAR_DECL
5933 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node))
5934 DECL_COMMON (decl) = 1;
5935 else
5936 {
5937 gcc_assert (TARGET_SUPPORTS_WEAK);
5938 DECL_WEAK (decl) = 1;
5939 }
5940 }
5941
5942 void
5943 init_varasm_once (void)
5944 {
5945 section_htab = htab_create_ggc (31, section_entry_hash,
5946 section_entry_eq, NULL);
5947 object_block_htab = htab_create_ggc (31, object_block_entry_hash,
5948 object_block_entry_eq, NULL);
5949 const_desc_htab = htab_create_ggc (1009, const_desc_hash,
5950 const_desc_eq, NULL);
5951
5952 const_alias_set = new_alias_set ();
5953 shared_constant_pool = create_constant_pool ();
5954
5955 #ifdef TEXT_SECTION_ASM_OP
5956 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
5957 TEXT_SECTION_ASM_OP);
5958 #endif
5959
5960 #ifdef DATA_SECTION_ASM_OP
5961 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5962 DATA_SECTION_ASM_OP);
5963 #endif
5964
5965 #ifdef SDATA_SECTION_ASM_OP
5966 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5967 SDATA_SECTION_ASM_OP);
5968 #endif
5969
5970 #ifdef READONLY_DATA_SECTION_ASM_OP
5971 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
5972 READONLY_DATA_SECTION_ASM_OP);
5973 #endif
5974
5975 #ifdef CTORS_SECTION_ASM_OP
5976 ctors_section = get_unnamed_section (0, output_section_asm_op,
5977 CTORS_SECTION_ASM_OP);
5978 #endif
5979
5980 #ifdef DTORS_SECTION_ASM_OP
5981 dtors_section = get_unnamed_section (0, output_section_asm_op,
5982 DTORS_SECTION_ASM_OP);
5983 #endif
5984
5985 #ifdef BSS_SECTION_ASM_OP
5986 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5987 output_section_asm_op,
5988 BSS_SECTION_ASM_OP);
5989 #endif
5990
5991 #ifdef SBSS_SECTION_ASM_OP
5992 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5993 output_section_asm_op,
5994 SBSS_SECTION_ASM_OP);
5995 #endif
5996
5997 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5998 | SECTION_COMMON, emit_tls_common);
5999 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6000 | SECTION_COMMON, emit_local);
6001 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6002 | SECTION_COMMON, emit_common);
6003
6004 #if defined ASM_OUTPUT_ALIGNED_BSS
6005 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
6006 emit_bss);
6007 #endif
6008
6009 targetm.asm_out.init_sections ();
6010
6011 if (readonly_data_section == NULL)
6012 readonly_data_section = text_section;
6013
6014 #ifdef ASM_OUTPUT_EXTERNAL
6015 pending_assemble_externals_set = pointer_set_create ();
6016 #endif
6017 }
6018
6019 enum tls_model
6020 decl_default_tls_model (const_tree decl)
6021 {
6022 enum tls_model kind;
6023 bool is_local;
6024
6025 is_local = targetm.binds_local_p (decl);
6026 if (!flag_shlib)
6027 {
6028 if (is_local)
6029 kind = TLS_MODEL_LOCAL_EXEC;
6030 else
6031 kind = TLS_MODEL_INITIAL_EXEC;
6032 }
6033
6034 /* Local dynamic is inefficient when we're not combining the
6035 parts of the address. */
6036 else if (optimize && is_local)
6037 kind = TLS_MODEL_LOCAL_DYNAMIC;
6038 else
6039 kind = TLS_MODEL_GLOBAL_DYNAMIC;
6040 if (kind < flag_tls_default)
6041 kind = flag_tls_default;
6042
6043 return kind;
6044 }
6045
6046 /* Select a set of attributes for section NAME based on the properties
6047 of DECL and whether or not RELOC indicates that DECL's initializer
6048 might contain runtime relocations.
6049
6050 We make the section read-only and executable for a function decl,
6051 read-only for a const data decl, and writable for a non-const data decl. */
6052
6053 unsigned int
6054 default_section_type_flags (tree decl, const char *name, int reloc)
6055 {
6056 unsigned int flags;
6057
6058 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6059 flags = SECTION_CODE;
6060 else if (decl)
6061 {
6062 enum section_category category
6063 = categorize_decl_for_section (decl, reloc);
6064 if (decl_readonly_section_1 (category))
6065 flags = 0;
6066 else if (category == SECCAT_DATA_REL_RO
6067 || category == SECCAT_DATA_REL_RO_LOCAL)
6068 flags = SECTION_WRITE | SECTION_RELRO;
6069 else
6070 flags = SECTION_WRITE;
6071 }
6072 else
6073 {
6074 flags = SECTION_WRITE;
6075 if (strcmp (name, ".data.rel.ro") == 0
6076 || strcmp (name, ".data.rel.ro.local") == 0)
6077 flags |= SECTION_RELRO;
6078 }
6079
6080 if (decl && DECL_P (decl) && DECL_ONE_ONLY (decl))
6081 flags |= SECTION_LINKONCE;
6082
6083 if (strcmp (name, ".vtable_map_vars") == 0)
6084 flags |= SECTION_LINKONCE;
6085
6086 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6087 flags |= SECTION_TLS | SECTION_WRITE;
6088
6089 if (strcmp (name, ".bss") == 0
6090 || strncmp (name, ".bss.", 5) == 0
6091 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6092 || strcmp (name, ".sbss") == 0
6093 || strncmp (name, ".sbss.", 6) == 0
6094 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6095 flags |= SECTION_BSS;
6096
6097 if (strcmp (name, ".tdata") == 0
6098 || strncmp (name, ".tdata.", 7) == 0
6099 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6100 flags |= SECTION_TLS;
6101
6102 if (strcmp (name, ".tbss") == 0
6103 || strncmp (name, ".tbss.", 6) == 0
6104 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6105 flags |= SECTION_TLS | SECTION_BSS;
6106
6107 /* These three sections have special ELF types. They are neither
6108 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
6109 want to print a section type (@progbits or @nobits). If someone
6110 is silly enough to emit code or TLS variables to one of these
6111 sections, then don't handle them specially. */
6112 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6113 && (strcmp (name, ".init_array") == 0
6114 || strcmp (name, ".fini_array") == 0
6115 || strcmp (name, ".preinit_array") == 0))
6116 flags |= SECTION_NOTYPE;
6117
6118 return flags;
6119 }
6120
6121 /* Return true if the target supports some form of global BSS,
6122 either through bss_noswitch_section, or by selecting a BSS
6123 section in TARGET_ASM_SELECT_SECTION. */
6124
6125 bool
6126 have_global_bss_p (void)
6127 {
6128 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6129 }
6130
6131 /* Output assembly to switch to section NAME with attribute FLAGS.
6132 Four variants for common object file formats. */
6133
6134 void
6135 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6136 unsigned int flags ATTRIBUTE_UNUSED,
6137 tree decl ATTRIBUTE_UNUSED)
6138 {
6139 /* Some object formats don't support named sections at all. The
6140 front-end should already have flagged this as an error. */
6141 gcc_unreachable ();
6142 }
6143
6144 #ifndef TLS_SECTION_ASM_FLAG
6145 #define TLS_SECTION_ASM_FLAG 'T'
6146 #endif
6147
6148 void
6149 default_elf_asm_named_section (const char *name, unsigned int flags,
6150 tree decl ATTRIBUTE_UNUSED)
6151 {
6152 char flagchars[10], *f = flagchars;
6153
6154 /* If we have already declared this section, we can use an
6155 abbreviated form to switch back to it -- unless this section is
6156 part of a COMDAT groups, in which case GAS requires the full
6157 declaration every time. */
6158 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6159 && (flags & SECTION_DECLARED))
6160 {
6161 fprintf (asm_out_file, "\t.section\t%s\n", name);
6162 return;
6163 }
6164
6165 if (!(flags & SECTION_DEBUG))
6166 *f++ = 'a';
6167 if (flags & SECTION_EXCLUDE)
6168 *f++ = 'e';
6169 if (flags & SECTION_WRITE)
6170 *f++ = 'w';
6171 if (flags & SECTION_CODE)
6172 *f++ = 'x';
6173 if (flags & SECTION_SMALL)
6174 *f++ = 's';
6175 if (flags & SECTION_MERGE)
6176 *f++ = 'M';
6177 if (flags & SECTION_STRINGS)
6178 *f++ = 'S';
6179 if (flags & SECTION_TLS)
6180 *f++ = TLS_SECTION_ASM_FLAG;
6181 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6182 *f++ = 'G';
6183 *f = '\0';
6184
6185 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6186
6187 if (!(flags & SECTION_NOTYPE))
6188 {
6189 const char *type;
6190 const char *format;
6191
6192 if (flags & SECTION_BSS)
6193 type = "nobits";
6194 else
6195 type = "progbits";
6196
6197 format = ",@%s";
6198 /* On platforms that use "@" as the assembly comment character,
6199 use "%" instead. */
6200 if (strcmp (ASM_COMMENT_START, "@") == 0)
6201 format = ",%%%s";
6202 fprintf (asm_out_file, format, type);
6203
6204 if (flags & SECTION_ENTSIZE)
6205 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6206 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6207 {
6208 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6209 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6210 else
6211 fprintf (asm_out_file, ",%s,comdat",
6212 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6213 }
6214 }
6215
6216 putc ('\n', asm_out_file);
6217 }
6218
6219 void
6220 default_coff_asm_named_section (const char *name, unsigned int flags,
6221 tree decl ATTRIBUTE_UNUSED)
6222 {
6223 char flagchars[8], *f = flagchars;
6224
6225 if (flags & SECTION_WRITE)
6226 *f++ = 'w';
6227 if (flags & SECTION_CODE)
6228 *f++ = 'x';
6229 *f = '\0';
6230
6231 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6232 }
6233
6234 void
6235 default_pe_asm_named_section (const char *name, unsigned int flags,
6236 tree decl)
6237 {
6238 default_coff_asm_named_section (name, flags, decl);
6239
6240 if (flags & SECTION_LINKONCE)
6241 {
6242 /* Functions may have been compiled at various levels of
6243 optimization so we can't use `same_size' here.
6244 Instead, have the linker pick one. */
6245 fprintf (asm_out_file, "\t.linkonce %s\n",
6246 (flags & SECTION_CODE ? "discard" : "same_size"));
6247 }
6248 }
6249 \f
6250 /* The lame default section selector. */
6251
6252 section *
6253 default_select_section (tree decl, int reloc,
6254 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6255 {
6256 if (DECL_P (decl))
6257 {
6258 if (decl_readonly_section (decl, reloc))
6259 return readonly_data_section;
6260 }
6261 else if (TREE_CODE (decl) == CONSTRUCTOR)
6262 {
6263 if (! ((flag_pic && reloc)
6264 || !TREE_READONLY (decl)
6265 || TREE_SIDE_EFFECTS (decl)
6266 || !TREE_CONSTANT (decl)))
6267 return readonly_data_section;
6268 }
6269 else if (TREE_CODE (decl) == STRING_CST)
6270 return readonly_data_section;
6271 else if (! (flag_pic && reloc))
6272 return readonly_data_section;
6273
6274 return data_section;
6275 }
6276
6277 enum section_category
6278 categorize_decl_for_section (const_tree decl, int reloc)
6279 {
6280 enum section_category ret;
6281
6282 if (TREE_CODE (decl) == FUNCTION_DECL)
6283 return SECCAT_TEXT;
6284 else if (TREE_CODE (decl) == STRING_CST)
6285 {
6286 if (flag_mudflap
6287 || ((flag_sanitize & SANITIZE_ADDRESS)
6288 && asan_protect_global (CONST_CAST_TREE (decl))))
6289 /* or !flag_merge_constants */
6290 return SECCAT_RODATA;
6291 else
6292 return SECCAT_RODATA_MERGE_STR;
6293 }
6294 else if (TREE_CODE (decl) == VAR_DECL)
6295 {
6296 if (bss_initializer_p (decl))
6297 ret = SECCAT_BSS;
6298 else if (! TREE_READONLY (decl)
6299 || TREE_SIDE_EFFECTS (decl)
6300 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
6301 {
6302 /* Here the reloc_rw_mask is not testing whether the section should
6303 be read-only or not, but whether the dynamic link will have to
6304 do something. If so, we wish to segregate the data in order to
6305 minimize cache misses inside the dynamic linker. */
6306 if (reloc & targetm.asm_out.reloc_rw_mask ())
6307 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6308 else
6309 ret = SECCAT_DATA;
6310 }
6311 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6312 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6313 else if (reloc || flag_merge_constants < 2 || flag_mudflap
6314 || ((flag_sanitize & SANITIZE_ADDRESS)
6315 && asan_protect_global (CONST_CAST_TREE (decl))))
6316 /* C and C++ don't allow different variables to share the same
6317 location. -fmerge-all-constants allows even that (at the
6318 expense of not conforming). */
6319 ret = SECCAT_RODATA;
6320 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6321 ret = SECCAT_RODATA_MERGE_STR_INIT;
6322 else
6323 ret = SECCAT_RODATA_MERGE_CONST;
6324 }
6325 else if (TREE_CODE (decl) == CONSTRUCTOR)
6326 {
6327 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6328 || TREE_SIDE_EFFECTS (decl)
6329 || ! TREE_CONSTANT (decl))
6330 ret = SECCAT_DATA;
6331 else
6332 ret = SECCAT_RODATA;
6333 }
6334 else
6335 ret = SECCAT_RODATA;
6336
6337 /* There are no read-only thread-local sections. */
6338 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6339 {
6340 /* Note that this would be *just* SECCAT_BSS, except that there's
6341 no concept of a read-only thread-local-data section. */
6342 if (ret == SECCAT_BSS
6343 || (flag_zero_initialized_in_bss
6344 && initializer_zerop (DECL_INITIAL (decl))))
6345 ret = SECCAT_TBSS;
6346 else
6347 ret = SECCAT_TDATA;
6348 }
6349
6350 /* If the target uses small data sections, select it. */
6351 else if (targetm.in_small_data_p (decl))
6352 {
6353 if (ret == SECCAT_BSS)
6354 ret = SECCAT_SBSS;
6355 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6356 ret = SECCAT_SRODATA;
6357 else
6358 ret = SECCAT_SDATA;
6359 }
6360
6361 return ret;
6362 }
6363
6364 static bool
6365 decl_readonly_section_1 (enum section_category category)
6366 {
6367 switch (category)
6368 {
6369 case SECCAT_RODATA:
6370 case SECCAT_RODATA_MERGE_STR:
6371 case SECCAT_RODATA_MERGE_STR_INIT:
6372 case SECCAT_RODATA_MERGE_CONST:
6373 case SECCAT_SRODATA:
6374 return true;
6375 default:
6376 return false;
6377 }
6378 }
6379
6380 bool
6381 decl_readonly_section (const_tree decl, int reloc)
6382 {
6383 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6384 }
6385
6386 /* Select a section based on the above categorization. */
6387
6388 section *
6389 default_elf_select_section (tree decl, int reloc,
6390 unsigned HOST_WIDE_INT align)
6391 {
6392 const char *sname;
6393 switch (categorize_decl_for_section (decl, reloc))
6394 {
6395 case SECCAT_TEXT:
6396 /* We're not supposed to be called on FUNCTION_DECLs. */
6397 gcc_unreachable ();
6398 case SECCAT_RODATA:
6399 return readonly_data_section;
6400 case SECCAT_RODATA_MERGE_STR:
6401 return mergeable_string_section (decl, align, 0);
6402 case SECCAT_RODATA_MERGE_STR_INIT:
6403 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6404 case SECCAT_RODATA_MERGE_CONST:
6405 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6406 case SECCAT_SRODATA:
6407 sname = ".sdata2";
6408 break;
6409 case SECCAT_DATA:
6410 return data_section;
6411 case SECCAT_DATA_REL:
6412 sname = ".data.rel";
6413 break;
6414 case SECCAT_DATA_REL_LOCAL:
6415 sname = ".data.rel.local";
6416 break;
6417 case SECCAT_DATA_REL_RO:
6418 sname = ".data.rel.ro";
6419 break;
6420 case SECCAT_DATA_REL_RO_LOCAL:
6421 sname = ".data.rel.ro.local";
6422 break;
6423 case SECCAT_SDATA:
6424 sname = ".sdata";
6425 break;
6426 case SECCAT_TDATA:
6427 sname = ".tdata";
6428 break;
6429 case SECCAT_BSS:
6430 if (bss_section)
6431 return bss_section;
6432 sname = ".bss";
6433 break;
6434 case SECCAT_SBSS:
6435 sname = ".sbss";
6436 break;
6437 case SECCAT_TBSS:
6438 sname = ".tbss";
6439 break;
6440 default:
6441 gcc_unreachable ();
6442 }
6443
6444 return get_named_section (decl, sname, reloc);
6445 }
6446
6447 /* Construct a unique section name based on the decl name and the
6448 categorization performed above. */
6449
6450 void
6451 default_unique_section (tree decl, int reloc)
6452 {
6453 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6454 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6455 const char *prefix, *name, *linkonce;
6456 char *string;
6457
6458 switch (categorize_decl_for_section (decl, reloc))
6459 {
6460 case SECCAT_TEXT:
6461 prefix = one_only ? ".t" : ".text";
6462 break;
6463 case SECCAT_RODATA:
6464 case SECCAT_RODATA_MERGE_STR:
6465 case SECCAT_RODATA_MERGE_STR_INIT:
6466 case SECCAT_RODATA_MERGE_CONST:
6467 prefix = one_only ? ".r" : ".rodata";
6468 break;
6469 case SECCAT_SRODATA:
6470 prefix = one_only ? ".s2" : ".sdata2";
6471 break;
6472 case SECCAT_DATA:
6473 prefix = one_only ? ".d" : ".data";
6474 break;
6475 case SECCAT_DATA_REL:
6476 prefix = one_only ? ".d.rel" : ".data.rel";
6477 break;
6478 case SECCAT_DATA_REL_LOCAL:
6479 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6480 break;
6481 case SECCAT_DATA_REL_RO:
6482 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6483 break;
6484 case SECCAT_DATA_REL_RO_LOCAL:
6485 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6486 break;
6487 case SECCAT_SDATA:
6488 prefix = one_only ? ".s" : ".sdata";
6489 break;
6490 case SECCAT_BSS:
6491 prefix = one_only ? ".b" : ".bss";
6492 break;
6493 case SECCAT_SBSS:
6494 prefix = one_only ? ".sb" : ".sbss";
6495 break;
6496 case SECCAT_TDATA:
6497 prefix = one_only ? ".td" : ".tdata";
6498 break;
6499 case SECCAT_TBSS:
6500 prefix = one_only ? ".tb" : ".tbss";
6501 break;
6502 default:
6503 gcc_unreachable ();
6504 }
6505
6506 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
6507 name = targetm.strip_name_encoding (name);
6508
6509 /* If we're using one_only, then there needs to be a .gnu.linkonce
6510 prefix to the section name. */
6511 linkonce = one_only ? ".gnu.linkonce" : "";
6512
6513 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6514
6515 DECL_SECTION_NAME (decl) = build_string (strlen (string), string);
6516 }
6517
6518 /* Like compute_reloc_for_constant, except for an RTX. The return value
6519 is a mask for which bit 1 indicates a global relocation, and bit 0
6520 indicates a local relocation. */
6521
6522 static int
6523 compute_reloc_for_rtx_1 (rtx *xp, void *data)
6524 {
6525 int *preloc = (int *) data;
6526 rtx x = *xp;
6527
6528 switch (GET_CODE (x))
6529 {
6530 case SYMBOL_REF:
6531 *preloc |= SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6532 break;
6533 case LABEL_REF:
6534 *preloc |= 1;
6535 break;
6536 default:
6537 break;
6538 }
6539
6540 return 0;
6541 }
6542
6543 static int
6544 compute_reloc_for_rtx (rtx x)
6545 {
6546 int reloc;
6547
6548 switch (GET_CODE (x))
6549 {
6550 case CONST:
6551 case SYMBOL_REF:
6552 case LABEL_REF:
6553 reloc = 0;
6554 for_each_rtx (&x, compute_reloc_for_rtx_1, &reloc);
6555 return reloc;
6556
6557 default:
6558 return 0;
6559 }
6560 }
6561
6562 section *
6563 default_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
6564 rtx x,
6565 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6566 {
6567 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6568 return data_section;
6569 else
6570 return readonly_data_section;
6571 }
6572
6573 section *
6574 default_elf_select_rtx_section (enum machine_mode mode, rtx x,
6575 unsigned HOST_WIDE_INT align)
6576 {
6577 int reloc = compute_reloc_for_rtx (x);
6578
6579 /* ??? Handle small data here somehow. */
6580
6581 if (reloc & targetm.asm_out.reloc_rw_mask ())
6582 {
6583 if (reloc == 1)
6584 return get_named_section (NULL, ".data.rel.ro.local", 1);
6585 else
6586 return get_named_section (NULL, ".data.rel.ro", 3);
6587 }
6588
6589 return mergeable_constant_section (mode, align, 0);
6590 }
6591
6592 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6593
6594 void
6595 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6596 {
6597 rtx symbol;
6598 int flags;
6599
6600 /* Careful not to prod global register variables. */
6601 if (!MEM_P (rtl))
6602 return;
6603 symbol = XEXP (rtl, 0);
6604 if (GET_CODE (symbol) != SYMBOL_REF)
6605 return;
6606
6607 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6608 if (TREE_CODE (decl) == FUNCTION_DECL)
6609 flags |= SYMBOL_FLAG_FUNCTION;
6610 if (targetm.binds_local_p (decl))
6611 flags |= SYMBOL_FLAG_LOCAL;
6612 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6613 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6614 else if (targetm.in_small_data_p (decl))
6615 flags |= SYMBOL_FLAG_SMALL;
6616 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6617 being PUBLIC, the thing *must* be defined in this translation unit.
6618 Prevent this buglet from being propagated into rtl code as well. */
6619 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6620 flags |= SYMBOL_FLAG_EXTERNAL;
6621
6622 SYMBOL_REF_FLAGS (symbol) = flags;
6623 }
6624
6625 /* By default, we do nothing for encode_section_info, so we need not
6626 do anything but discard the '*' marker. */
6627
6628 const char *
6629 default_strip_name_encoding (const char *str)
6630 {
6631 return str + (*str == '*');
6632 }
6633
6634 #ifdef ASM_OUTPUT_DEF
6635 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6636 anchor relative to ".", the current section position. */
6637
6638 void
6639 default_asm_output_anchor (rtx symbol)
6640 {
6641 char buffer[100];
6642
6643 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6644 SYMBOL_REF_BLOCK_OFFSET (symbol));
6645 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6646 }
6647 #endif
6648
6649 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6650
6651 bool
6652 default_use_anchors_for_symbol_p (const_rtx symbol)
6653 {
6654 section *sect;
6655 tree decl;
6656
6657 /* Don't use anchors for mergeable sections. The linker might move
6658 the objects around. */
6659 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6660 if (sect->common.flags & SECTION_MERGE)
6661 return false;
6662
6663 /* Don't use anchors for small data sections. The small data register
6664 acts as an anchor for such sections. */
6665 if (sect->common.flags & SECTION_SMALL)
6666 return false;
6667
6668 decl = SYMBOL_REF_DECL (symbol);
6669 if (decl && DECL_P (decl))
6670 {
6671 /* Don't use section anchors for decls that might be defined or
6672 usurped by other modules. */
6673 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6674 return false;
6675
6676 /* Don't use section anchors for decls that will be placed in a
6677 small data section. */
6678 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6679 one above. The problem is that we only use SECTION_SMALL for
6680 sections that should be marked as small in the section directive. */
6681 if (targetm.in_small_data_p (decl))
6682 return false;
6683 }
6684 return true;
6685 }
6686
6687 /* Return true when RESOLUTION indicate that symbol will be bound to the
6688 definition provided by current .o file. */
6689
6690 static bool
6691 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
6692 {
6693 return (resolution == LDPR_PREVAILING_DEF
6694 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6695 || resolution == LDPR_PREVAILING_DEF_IRONLY);
6696 }
6697
6698 /* Return true when RESOLUTION indicate that symbol will be bound locally
6699 within current executable or DSO. */
6700
6701 static bool
6702 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
6703 {
6704 return (resolution == LDPR_PREVAILING_DEF
6705 || resolution == LDPR_PREVAILING_DEF_IRONLY
6706 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6707 || resolution == LDPR_PREEMPTED_REG
6708 || resolution == LDPR_PREEMPTED_IR
6709 || resolution == LDPR_RESOLVED_IR
6710 || resolution == LDPR_RESOLVED_EXEC);
6711 }
6712
6713 /* Assume ELF-ish defaults, since that's pretty much the most liberal
6714 wrt cross-module name binding. */
6715
6716 bool
6717 default_binds_local_p (const_tree exp)
6718 {
6719 return default_binds_local_p_1 (exp, flag_shlib);
6720 }
6721
6722 bool
6723 default_binds_local_p_1 (const_tree exp, int shlib)
6724 {
6725 bool local_p;
6726 bool resolved_locally = false;
6727 bool resolved_to_local_def = false;
6728
6729 /* With resolution file in hands, take look into resolutions.
6730 We can't just return true for resolved_locally symbols,
6731 because dynamic linking might overwrite symbols
6732 in shared libraries. */
6733 if (TREE_CODE (exp) == VAR_DECL && TREE_PUBLIC (exp)
6734 && (TREE_STATIC (exp) || DECL_EXTERNAL (exp)))
6735 {
6736 struct varpool_node *vnode = varpool_get_node (exp);
6737 if (vnode && resolution_local_p (vnode->symbol.resolution))
6738 resolved_locally = true;
6739 if (vnode
6740 && resolution_to_local_definition_p (vnode->symbol.resolution))
6741 resolved_to_local_def = true;
6742 }
6743 else if (TREE_CODE (exp) == FUNCTION_DECL && TREE_PUBLIC (exp))
6744 {
6745 struct cgraph_node *node = cgraph_get_node (exp);
6746 if (node
6747 && resolution_local_p (node->symbol.resolution))
6748 resolved_locally = true;
6749 if (node
6750 && resolution_to_local_definition_p (node->symbol.resolution))
6751 resolved_to_local_def = true;
6752 }
6753
6754 /* A non-decl is an entry in the constant pool. */
6755 if (!DECL_P (exp))
6756 local_p = true;
6757 /* Weakrefs may not bind locally, even though the weakref itself is always
6758 static and therefore local. Similarly, the resolver for ifunc functions
6759 might resolve to a non-local function.
6760 FIXME: We can resolve the weakref case more curefuly by looking at the
6761 weakref alias. */
6762 else if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
6763 || (TREE_CODE (exp) == FUNCTION_DECL
6764 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
6765 local_p = false;
6766 /* Static variables are always local. */
6767 else if (! TREE_PUBLIC (exp))
6768 local_p = true;
6769 /* A variable is local if the user has said explicitly that it will
6770 be. */
6771 else if ((DECL_VISIBILITY_SPECIFIED (exp)
6772 || resolved_to_local_def)
6773 && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6774 local_p = true;
6775 /* Variables defined outside this object might not be local. */
6776 else if (DECL_EXTERNAL (exp) && !resolved_locally)
6777 local_p = false;
6778 /* If defined in this object and visibility is not default, must be
6779 local. */
6780 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6781 local_p = true;
6782 /* Default visibility weak data can be overridden by a strong symbol
6783 in another module and so are not local. */
6784 else if (DECL_WEAK (exp)
6785 && !resolved_locally)
6786 local_p = false;
6787 /* If PIC, then assume that any global name can be overridden by
6788 symbols resolved from other modules. */
6789 else if (shlib)
6790 local_p = false;
6791 /* Uninitialized COMMON variable may be unified with symbols
6792 resolved from other modules. */
6793 else if (DECL_COMMON (exp)
6794 && !resolved_locally
6795 && (DECL_INITIAL (exp) == NULL
6796 || DECL_INITIAL (exp) == error_mark_node))
6797 local_p = false;
6798 /* Otherwise we're left with initialized (or non-common) global data
6799 which is of necessity defined locally. */
6800 else
6801 local_p = true;
6802
6803 return local_p;
6804 }
6805
6806 /* Return true when references to DECL must bind to current definition in
6807 final executable.
6808
6809 The condition is usually equivalent to whether the function binds to the
6810 current module (shared library or executable), that is to binds_local_p.
6811 We use this fact to avoid need for another target hook and implement
6812 the logic using binds_local_p and just special cases where
6813 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
6814 the weak definitions (that can be overwritten at linktime by other
6815 definition from different object file) and when resolution info is available
6816 we simply use the knowledge passed to us by linker plugin. */
6817 bool
6818 decl_binds_to_current_def_p (tree decl)
6819 {
6820 gcc_assert (DECL_P (decl));
6821 if (!targetm.binds_local_p (decl))
6822 return false;
6823 if (!TREE_PUBLIC (decl))
6824 return true;
6825 /* When resolution is available, just use it. */
6826 if (TREE_CODE (decl) == VAR_DECL
6827 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl)))
6828 {
6829 struct varpool_node *vnode = varpool_get_node (decl);
6830 if (vnode
6831 && vnode->symbol.resolution != LDPR_UNKNOWN)
6832 return resolution_to_local_definition_p (vnode->symbol.resolution);
6833 }
6834 else if (TREE_CODE (decl) == FUNCTION_DECL)
6835 {
6836 struct cgraph_node *node = cgraph_get_node (decl);
6837 if (node
6838 && node->symbol.resolution != LDPR_UNKNOWN)
6839 return resolution_to_local_definition_p (node->symbol.resolution);
6840 }
6841 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
6842 binds locally but still can be overwritten), DECL_COMMON (can be merged
6843 with a non-common definition somewhere in the same module) or
6844 DECL_EXTERNAL.
6845 This rely on fact that binds_local_p behave as decl_replaceable_p
6846 for all other declaration types. */
6847 if (DECL_WEAK (decl))
6848 return false;
6849 if (DECL_COMMON (decl)
6850 && (DECL_INITIAL (decl) == NULL
6851 || DECL_INITIAL (decl) == error_mark_node))
6852 return false;
6853 if (DECL_EXTERNAL (decl))
6854 return false;
6855 return true;
6856 }
6857
6858 /* A replaceable function or variable is one which may be replaced
6859 at link-time with an entirely different definition, provided that the
6860 replacement has the same type. For example, functions declared
6861 with __attribute__((weak)) on most systems are replaceable.
6862
6863 COMDAT functions are not replaceable, since all definitions of the
6864 function must be equivalent. It is important that COMDAT functions
6865 not be treated as replaceable so that use of C++ template
6866 instantiations is not penalized. */
6867
6868 bool
6869 decl_replaceable_p (tree decl)
6870 {
6871 gcc_assert (DECL_P (decl));
6872 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
6873 return false;
6874 return !decl_binds_to_current_def_p (decl);
6875 }
6876
6877 /* Default function to output code that will globalize a label. A
6878 target must define GLOBAL_ASM_OP or provide its own function to
6879 globalize a label. */
6880 #ifdef GLOBAL_ASM_OP
6881 void
6882 default_globalize_label (FILE * stream, const char *name)
6883 {
6884 fputs (GLOBAL_ASM_OP, stream);
6885 assemble_name (stream, name);
6886 putc ('\n', stream);
6887 }
6888 #endif /* GLOBAL_ASM_OP */
6889
6890 /* Default function to output code that will globalize a declaration. */
6891 void
6892 default_globalize_decl_name (FILE * stream, tree decl)
6893 {
6894 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
6895 targetm.asm_out.globalize_label (stream, name);
6896 }
6897
6898 /* Default function to output a label for unwind information. The
6899 default is to do nothing. A target that needs nonlocal labels for
6900 unwind information must provide its own function to do this. */
6901 void
6902 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
6903 tree decl ATTRIBUTE_UNUSED,
6904 int for_eh ATTRIBUTE_UNUSED,
6905 int empty ATTRIBUTE_UNUSED)
6906 {
6907 }
6908
6909 /* Default function to output a label to divide up the exception table.
6910 The default is to do nothing. A target that needs/wants to divide
6911 up the table must provide it's own function to do this. */
6912 void
6913 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
6914 {
6915 }
6916
6917 /* This is how to output an internal numbered label where PREFIX is
6918 the class of label and LABELNO is the number within the class. */
6919
6920 void
6921 default_generate_internal_label (char *buf, const char *prefix,
6922 unsigned long labelno)
6923 {
6924 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6925 }
6926
6927 /* This is how to output an internal numbered label where PREFIX is
6928 the class of label and LABELNO is the number within the class. */
6929
6930 void
6931 default_internal_label (FILE *stream, const char *prefix,
6932 unsigned long labelno)
6933 {
6934 char *const buf = (char *) alloca (40 + strlen (prefix));
6935 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6936 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
6937 }
6938
6939
6940 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
6941
6942 void
6943 default_asm_declare_constant_name (FILE *file, const char *name,
6944 const_tree exp ATTRIBUTE_UNUSED,
6945 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
6946 {
6947 assemble_label (file, name);
6948 }
6949
6950 /* This is the default behavior at the beginning of a file. It's
6951 controlled by two other target-hook toggles. */
6952 void
6953 default_file_start (void)
6954 {
6955 if (targetm.asm_file_start_app_off
6956 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
6957 fputs (ASM_APP_OFF, asm_out_file);
6958
6959 if (targetm.asm_file_start_file_directive)
6960 output_file_directive (asm_out_file, main_input_filename);
6961 }
6962
6963 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
6964 which emits a special section directive used to indicate whether or
6965 not this object file needs an executable stack. This is primarily
6966 a GNU extension to ELF but could be used on other targets. */
6967
6968 int trampolines_created;
6969
6970 void
6971 file_end_indicate_exec_stack (void)
6972 {
6973 unsigned int flags = SECTION_DEBUG;
6974 if (trampolines_created)
6975 flags |= SECTION_CODE;
6976
6977 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
6978 }
6979
6980 /* Emit a special section directive to indicate that this object file
6981 was compiled with -fsplit-stack. This is used to let the linker
6982 detect calls between split-stack code and non-split-stack code, so
6983 that it can modify the split-stack code to allocate a sufficiently
6984 large stack. We emit another special section if there are any
6985 functions in this file which have the no_split_stack attribute, to
6986 prevent the linker from warning about being unable to convert the
6987 functions if they call non-split-stack code. */
6988
6989 void
6990 file_end_indicate_split_stack (void)
6991 {
6992 if (flag_split_stack)
6993 {
6994 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
6995 NULL));
6996 if (saw_no_split_stack)
6997 switch_to_section (get_section (".note.GNU-no-split-stack",
6998 SECTION_DEBUG, NULL));
6999 }
7000 }
7001
7002 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
7003 a get_unnamed_section callback. */
7004
7005 void
7006 output_section_asm_op (const void *directive)
7007 {
7008 fprintf (asm_out_file, "%s\n", (const char *) directive);
7009 }
7010
7011 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
7012 the current section is NEW_SECTION. */
7013
7014 void
7015 switch_to_section (section *new_section)
7016 {
7017 if (in_section == new_section)
7018 return;
7019
7020 if (new_section->common.flags & SECTION_FORGET)
7021 in_section = NULL;
7022 else
7023 in_section = new_section;
7024
7025 switch (SECTION_STYLE (new_section))
7026 {
7027 case SECTION_NAMED:
7028 targetm.asm_out.named_section (new_section->named.name,
7029 new_section->named.common.flags,
7030 new_section->named.decl);
7031 break;
7032
7033 case SECTION_UNNAMED:
7034 new_section->unnamed.callback (new_section->unnamed.data);
7035 break;
7036
7037 case SECTION_NOSWITCH:
7038 gcc_unreachable ();
7039 break;
7040 }
7041
7042 new_section->common.flags |= SECTION_DECLARED;
7043 }
7044
7045 /* If block symbol SYMBOL has not yet been assigned an offset, place
7046 it at the end of its block. */
7047
7048 void
7049 place_block_symbol (rtx symbol)
7050 {
7051 unsigned HOST_WIDE_INT size, mask, offset;
7052 struct constant_descriptor_rtx *desc;
7053 unsigned int alignment;
7054 struct object_block *block;
7055 tree decl;
7056
7057 gcc_assert (SYMBOL_REF_BLOCK (symbol));
7058 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7059 return;
7060
7061 /* Work out the symbol's size and alignment. */
7062 if (CONSTANT_POOL_ADDRESS_P (symbol))
7063 {
7064 desc = SYMBOL_REF_CONSTANT (symbol);
7065 alignment = desc->align;
7066 size = GET_MODE_SIZE (desc->mode);
7067 }
7068 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7069 {
7070 decl = SYMBOL_REF_DECL (symbol);
7071 alignment = DECL_ALIGN (decl);
7072 size = get_constant_size (DECL_INITIAL (decl));
7073 if ((flag_sanitize & SANITIZE_ADDRESS)
7074 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7075 && asan_protect_global (DECL_INITIAL (decl)))
7076 size += asan_red_zone_size (size);
7077 }
7078 else
7079 {
7080 decl = SYMBOL_REF_DECL (symbol);
7081 alignment = get_variable_align (decl);
7082 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7083 if ((flag_sanitize & SANITIZE_ADDRESS)
7084 && asan_protect_global (decl))
7085 {
7086 size += asan_red_zone_size (size);
7087 alignment = MAX (alignment,
7088 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7089 }
7090 }
7091
7092 /* Calculate the object's offset from the start of the block. */
7093 block = SYMBOL_REF_BLOCK (symbol);
7094 mask = alignment / BITS_PER_UNIT - 1;
7095 offset = (block->size + mask) & ~mask;
7096 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7097
7098 /* Record the block's new alignment and size. */
7099 block->alignment = MAX (block->alignment, alignment);
7100 block->size = offset + size;
7101
7102 vec_safe_push (block->objects, symbol);
7103 }
7104
7105 /* Return the anchor that should be used to address byte offset OFFSET
7106 from the first object in BLOCK. MODEL is the TLS model used
7107 to access it. */
7108
7109 rtx
7110 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7111 enum tls_model model)
7112 {
7113 char label[100];
7114 unsigned int begin, middle, end;
7115 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7116 rtx anchor;
7117
7118 /* Work out the anchor's offset. Use an offset of 0 for the first
7119 anchor so that we don't pessimize the case where we take the address
7120 of a variable at the beginning of the block. This is particularly
7121 useful when a block has only one variable assigned to it.
7122
7123 We try to place anchors RANGE bytes apart, so there can then be
7124 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7125 a ptr_mode offset. With some target settings, the lowest such
7126 anchor might be out of range for the lowest ptr_mode offset;
7127 likewise the highest anchor for the highest offset. Use anchors
7128 at the extreme ends of the ptr_mode range in such cases.
7129
7130 All arithmetic uses unsigned integers in order to avoid
7131 signed overflow. */
7132 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7133 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7134 range = max_offset - min_offset + 1;
7135 if (range == 0)
7136 offset = 0;
7137 else
7138 {
7139 bias = 1 << (GET_MODE_BITSIZE (ptr_mode) - 1);
7140 if (offset < 0)
7141 {
7142 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7143 delta -= delta % range;
7144 if (delta > bias)
7145 delta = bias;
7146 offset = (HOST_WIDE_INT) (-delta);
7147 }
7148 else
7149 {
7150 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7151 delta -= delta % range;
7152 if (delta > bias - 1)
7153 delta = bias - 1;
7154 offset = (HOST_WIDE_INT) delta;
7155 }
7156 }
7157
7158 /* Do a binary search to see if there's already an anchor we can use.
7159 Set BEGIN to the new anchor's index if not. */
7160 begin = 0;
7161 end = vec_safe_length (block->anchors);
7162 while (begin != end)
7163 {
7164 middle = (end + begin) / 2;
7165 anchor = (*block->anchors)[middle];
7166 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7167 end = middle;
7168 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7169 begin = middle + 1;
7170 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7171 end = middle;
7172 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7173 begin = middle + 1;
7174 else
7175 return anchor;
7176 }
7177
7178 /* Create a new anchor with a unique label. */
7179 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7180 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7181 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7182 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7183
7184 /* Insert it at index BEGIN. */
7185 vec_safe_insert (block->anchors, begin, anchor);
7186 return anchor;
7187 }
7188
7189 /* Output the objects in BLOCK. */
7190
7191 static void
7192 output_object_block (struct object_block *block)
7193 {
7194 struct constant_descriptor_rtx *desc;
7195 unsigned int i;
7196 HOST_WIDE_INT offset;
7197 tree decl;
7198 rtx symbol;
7199
7200 if (!block->objects)
7201 return;
7202
7203 /* Switch to the section and make sure that the first byte is
7204 suitably aligned. */
7205 switch_to_section (block->sect);
7206 assemble_align (block->alignment);
7207
7208 /* Define the values of all anchors relative to the current section
7209 position. */
7210 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7211 targetm.asm_out.output_anchor (symbol);
7212
7213 /* Output the objects themselves. */
7214 offset = 0;
7215 FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7216 {
7217 /* Move to the object's offset, padding with zeros if necessary. */
7218 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7219 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7220 if (CONSTANT_POOL_ADDRESS_P (symbol))
7221 {
7222 desc = SYMBOL_REF_CONSTANT (symbol);
7223 output_constant_pool_1 (desc, 1);
7224 offset += GET_MODE_SIZE (desc->mode);
7225 }
7226 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7227 {
7228 HOST_WIDE_INT size;
7229 decl = SYMBOL_REF_DECL (symbol);
7230 assemble_constant_contents (DECL_INITIAL (decl), XSTR (symbol, 0),
7231 DECL_ALIGN (decl));
7232 size = get_constant_size (DECL_INITIAL (decl));
7233 offset += size;
7234 if ((flag_sanitize & SANITIZE_ADDRESS)
7235 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7236 && asan_protect_global (DECL_INITIAL (decl)))
7237 {
7238 size = asan_red_zone_size (size);
7239 assemble_zeros (size);
7240 offset += size;
7241 }
7242 }
7243 else
7244 {
7245 HOST_WIDE_INT size;
7246 decl = SYMBOL_REF_DECL (symbol);
7247 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7248 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7249 offset += size;
7250 if ((flag_sanitize & SANITIZE_ADDRESS)
7251 && asan_protect_global (decl))
7252 {
7253 size = asan_red_zone_size (size);
7254 assemble_zeros (size);
7255 offset += size;
7256 }
7257 }
7258 }
7259 }
7260
7261 /* A htab_traverse callback used to call output_object_block for
7262 each member of object_block_htab. */
7263
7264 static int
7265 output_object_block_htab (void **slot, void *data ATTRIBUTE_UNUSED)
7266 {
7267 output_object_block ((struct object_block *) (*slot));
7268 return 1;
7269 }
7270
7271 /* Output the definitions of all object_blocks. */
7272
7273 void
7274 output_object_blocks (void)
7275 {
7276 htab_traverse (object_block_htab, output_object_block_htab, NULL);
7277 }
7278
7279 /* This function provides a possible implementation of the
7280 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7281 by -frecord-gcc-switches it creates a new mergeable, string section in the
7282 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7283 contains the switches in ASCII format.
7284
7285 FIXME: This code does not correctly handle double quote characters
7286 that appear inside strings, (it strips them rather than preserving them).
7287 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7288 characters - instead it treats them as sub-string separators. Since
7289 we want to emit NUL strings terminators into the object file we have to use
7290 ASM_OUTPUT_SKIP. */
7291
7292 int
7293 elf_record_gcc_switches (print_switch_type type, const char * name)
7294 {
7295 switch (type)
7296 {
7297 case SWITCH_TYPE_PASSED:
7298 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7299 ASM_OUTPUT_SKIP (asm_out_file, (unsigned HOST_WIDE_INT) 1);
7300 break;
7301
7302 case SWITCH_TYPE_DESCRIPTIVE:
7303 if (name == NULL)
7304 {
7305 /* Distinguish between invocations where name is NULL. */
7306 static bool started = false;
7307
7308 if (!started)
7309 {
7310 section * sec;
7311
7312 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7313 SECTION_DEBUG
7314 | SECTION_MERGE
7315 | SECTION_STRINGS
7316 | (SECTION_ENTSIZE & 1),
7317 NULL);
7318 switch_to_section (sec);
7319 started = true;
7320 }
7321 }
7322
7323 default:
7324 break;
7325 }
7326
7327 /* The return value is currently ignored by the caller, but must be 0.
7328 For -fverbose-asm the return value would be the number of characters
7329 emitted into the assembler file. */
7330 return 0;
7331 }
7332
7333 /* Emit text to declare externally defined symbols. It is needed to
7334 properly support non-default visibility. */
7335 void
7336 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7337 tree decl,
7338 const char *name ATTRIBUTE_UNUSED)
7339 {
7340 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7341 set in order to avoid putting out names that are never really
7342 used. */
7343 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7344 && targetm.binds_local_p (decl))
7345 maybe_assemble_visibility (decl);
7346 }
7347
7348 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7349
7350 void
7351 default_asm_output_source_filename (FILE *file, const char *name)
7352 {
7353 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7354 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7355 #else
7356 fprintf (file, "\t.file\t");
7357 output_quoted_string (file, name);
7358 putc ('\n', file);
7359 #endif
7360 }
7361
7362 /* Output a file name in the form wanted by System V. */
7363
7364 void
7365 output_file_directive (FILE *asm_file, const char *input_name)
7366 {
7367 int len;
7368 const char *na;
7369
7370 if (input_name == NULL)
7371 input_name = "<stdin>";
7372 else
7373 input_name = remap_debug_filename (input_name);
7374
7375 len = strlen (input_name);
7376 na = input_name + len;
7377
7378 /* NA gets INPUT_NAME sans directory names. */
7379 while (na > input_name)
7380 {
7381 if (IS_DIR_SEPARATOR (na[-1]))
7382 break;
7383 na--;
7384 }
7385
7386 targetm.asm_out.output_source_filename (asm_file, na);
7387 }
7388
7389 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7390 EXP. */
7391 rtx
7392 make_debug_expr_from_rtl (const_rtx exp)
7393 {
7394 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7395 enum machine_mode mode = GET_MODE (exp);
7396 rtx dval;
7397
7398 DECL_ARTIFICIAL (ddecl) = 1;
7399 if (REG_P (exp) && REG_EXPR (exp))
7400 type = TREE_TYPE (REG_EXPR (exp));
7401 else if (MEM_P (exp) && MEM_EXPR (exp))
7402 type = TREE_TYPE (MEM_EXPR (exp));
7403 else
7404 type = NULL_TREE;
7405 if (type && TYPE_MODE (type) == mode)
7406 TREE_TYPE (ddecl) = type;
7407 else
7408 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7409 DECL_MODE (ddecl) = mode;
7410 dval = gen_rtx_DEBUG_EXPR (mode);
7411 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7412 SET_DECL_RTL (ddecl, dval);
7413 return dval;
7414 }
7415
7416 #ifdef ELF_ASCII_ESCAPES
7417 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7418
7419 void
7420 default_elf_asm_output_limited_string (FILE *f, const char *s)
7421 {
7422 int escape;
7423 unsigned char c;
7424
7425 fputs (STRING_ASM_OP, f);
7426 putc ('"', f);
7427 while (*s != '\0')
7428 {
7429 c = *s;
7430 escape = ELF_ASCII_ESCAPES[c];
7431 switch (escape)
7432 {
7433 case 0:
7434 putc (c, f);
7435 break;
7436 case 1:
7437 /* TODO: Print in hex with fast function, important for -flto. */
7438 fprintf (f, "\\%03o", c);
7439 break;
7440 default:
7441 putc ('\\', f);
7442 putc (escape, f);
7443 break;
7444 }
7445 s++;
7446 }
7447 putc ('\"', f);
7448 putc ('\n', f);
7449 }
7450
7451 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7452
7453 void
7454 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7455 {
7456 const char *limit = s + len;
7457 const char *last_null = NULL;
7458 unsigned bytes_in_chunk = 0;
7459 unsigned char c;
7460 int escape;
7461
7462 for (; s < limit; s++)
7463 {
7464 const char *p;
7465
7466 if (bytes_in_chunk >= 60)
7467 {
7468 putc ('\"', f);
7469 putc ('\n', f);
7470 bytes_in_chunk = 0;
7471 }
7472
7473 if (s > last_null)
7474 {
7475 for (p = s; p < limit && *p != '\0'; p++)
7476 continue;
7477 last_null = p;
7478 }
7479 else
7480 p = last_null;
7481
7482 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7483 {
7484 if (bytes_in_chunk > 0)
7485 {
7486 putc ('\"', f);
7487 putc ('\n', f);
7488 bytes_in_chunk = 0;
7489 }
7490
7491 default_elf_asm_output_limited_string (f, s);
7492 s = p;
7493 }
7494 else
7495 {
7496 if (bytes_in_chunk == 0)
7497 fputs (ASCII_DATA_ASM_OP "\"", f);
7498
7499 c = *s;
7500 escape = ELF_ASCII_ESCAPES[c];
7501 switch (escape)
7502 {
7503 case 0:
7504 putc (c, f);
7505 bytes_in_chunk++;
7506 break;
7507 case 1:
7508 /* TODO: Print in hex with fast function, important for -flto. */
7509 fprintf (f, "\\%03o", c);
7510 bytes_in_chunk += 4;
7511 break;
7512 default:
7513 putc ('\\', f);
7514 putc (escape, f);
7515 bytes_in_chunk += 2;
7516 break;
7517 }
7518
7519 }
7520 }
7521
7522 if (bytes_in_chunk > 0)
7523 {
7524 putc ('\"', f);
7525 putc ('\n', f);
7526 }
7527 }
7528 #endif
7529
7530 static GTY(()) section *elf_init_array_section;
7531 static GTY(()) section *elf_fini_array_section;
7532
7533 static section *
7534 get_elf_initfini_array_priority_section (int priority,
7535 bool constructor_p)
7536 {
7537 section *sec;
7538 if (priority != DEFAULT_INIT_PRIORITY)
7539 {
7540 char buf[18];
7541 sprintf (buf, "%s.%.5u",
7542 constructor_p ? ".init_array" : ".fini_array",
7543 priority);
7544 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7545 }
7546 else
7547 {
7548 if (constructor_p)
7549 {
7550 if (elf_init_array_section == NULL)
7551 elf_init_array_section
7552 = get_section (".init_array",
7553 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7554 sec = elf_init_array_section;
7555 }
7556 else
7557 {
7558 if (elf_fini_array_section == NULL)
7559 elf_fini_array_section
7560 = get_section (".fini_array",
7561 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7562 sec = elf_fini_array_section;
7563 }
7564 }
7565 return sec;
7566 }
7567
7568 /* Use .init_array section for constructors. */
7569
7570 void
7571 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7572 {
7573 section *sec = get_elf_initfini_array_priority_section (priority,
7574 true);
7575 assemble_addr_to_section (symbol, sec);
7576 }
7577
7578 /* Use .fini_array section for destructors. */
7579
7580 void
7581 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7582 {
7583 section *sec = get_elf_initfini_array_priority_section (priority,
7584 false);
7585 assemble_addr_to_section (symbol, sec);
7586 }
7587
7588 /* Default TARGET_ASM_OUTPUT_IDENT hook.
7589
7590 This is a bit of a cheat. The real default is a no-op, but this
7591 hook is the default for all targets with a .ident directive. */
7592
7593 void
7594 default_asm_output_ident_directive (const char *ident_str)
7595 {
7596 const char *ident_asm_op = "\t.ident\t";
7597
7598 /* If we are still in the front end, do not write out the string
7599 to asm_out_file. Instead, add a fake top-level asm statement.
7600 This allows the front ends to use this hook without actually
7601 writing to asm_out_file, to handle #ident or Pragma Ident. */
7602 if (cgraph_state == CGRAPH_STATE_PARSING)
7603 {
7604 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
7605 add_asm_node (build_string (strlen (buf), buf));
7606 }
7607 else
7608 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
7609 }
7610
7611 #include "gt-varasm.h"