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[official-gcc.git] / gcc / varasm.c
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1 /* Output variables, constants and external declarations, for GNU compiler.
2 Copyright (C) 1987-2014 Free Software Foundation, Inc.
4 This file is part of GCC.
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.
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.
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/>. */
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.
25 We also output the assembler code for constants stored in memory
26 and are responsible for combining constants with the same value. */
28 #include "config.h"
29 #include "system.h"
30 #include "coretypes.h"
31 #include "tm.h"
32 #include "rtl.h"
33 #include "tree.h"
34 #include "stor-layout.h"
35 #include "stringpool.h"
36 #include "varasm.h"
37 #include "flags.h"
38 #include "function.h"
39 #include "expr.h"
40 #include "hard-reg-set.h"
41 #include "regs.h"
42 #include "output.h"
43 #include "diagnostic-core.h"
44 #include "hashtab.h"
45 #include "ggc.h"
46 #include "langhooks.h"
47 #include "tm_p.h"
48 #include "debug.h"
49 #include "target.h"
50 #include "common/common-target.h"
51 #include "targhooks.h"
52 #include "cgraph.h"
53 #include "hash-set.h"
54 #include "asan.h"
55 #include "basic-block.h"
57 #ifdef XCOFF_DEBUGGING_INFO
58 #include "xcoffout.h" /* Needed for external data
59 declarations for e.g. AIX 4.x. */
60 #endif
62 /* The (assembler) name of the first globally-visible object output. */
63 extern GTY(()) const char *first_global_object_name;
64 extern GTY(()) const char *weak_global_object_name;
66 const char *first_global_object_name;
67 const char *weak_global_object_name;
69 struct addr_const;
70 struct constant_descriptor_rtx;
71 struct rtx_constant_pool;
73 #define n_deferred_constants (crtl->varasm.deferred_constants)
75 /* Number for making the label on the next
76 constant that is stored in memory. */
78 static GTY(()) int const_labelno;
80 /* Carry information from ASM_DECLARE_OBJECT_NAME
81 to ASM_FINISH_DECLARE_OBJECT. */
83 int size_directive_output;
85 /* The last decl for which assemble_variable was called,
86 if it did ASM_DECLARE_OBJECT_NAME.
87 If the last call to assemble_variable didn't do that,
88 this holds 0. */
90 tree last_assemble_variable_decl;
92 /* The following global variable indicates if the first basic block
93 in a function belongs to the cold partition or not. */
95 bool first_function_block_is_cold;
97 /* We give all constants their own alias set. Perhaps redundant with
98 MEM_READONLY_P, but pre-dates it. */
100 static alias_set_type const_alias_set;
102 /* Whether we saw any functions with no_split_stack. */
104 static bool saw_no_split_stack;
106 static const char *strip_reg_name (const char *);
107 static int contains_pointers_p (tree);
108 #ifdef ASM_OUTPUT_EXTERNAL
109 static bool incorporeal_function_p (tree);
110 #endif
111 static void decode_addr_const (tree, struct addr_const *);
112 static hashval_t const_desc_hash (const void *);
113 static int const_desc_eq (const void *, const void *);
114 static hashval_t const_hash_1 (const tree);
115 static int compare_constant (const tree, const tree);
116 static void output_constant_def_contents (rtx);
117 static void output_addressed_constants (tree);
118 static unsigned HOST_WIDE_INT output_constant (tree, unsigned HOST_WIDE_INT,
119 unsigned int);
120 static void globalize_decl (tree);
121 static bool decl_readonly_section_1 (enum section_category);
122 #ifdef BSS_SECTION_ASM_OP
123 #ifdef ASM_OUTPUT_ALIGNED_BSS
124 static void asm_output_aligned_bss (FILE *, tree, const char *,
125 unsigned HOST_WIDE_INT, int)
126 ATTRIBUTE_UNUSED;
127 #endif
128 #endif /* BSS_SECTION_ASM_OP */
129 static void mark_weak (tree);
130 static void output_constant_pool (const char *, tree);
132 /* Well-known sections, each one associated with some sort of *_ASM_OP. */
133 section *text_section;
134 section *data_section;
135 section *readonly_data_section;
136 section *sdata_section;
137 section *ctors_section;
138 section *dtors_section;
139 section *bss_section;
140 section *sbss_section;
142 /* Various forms of common section. All are guaranteed to be nonnull. */
143 section *tls_comm_section;
144 section *comm_section;
145 section *lcomm_section;
147 /* A SECTION_NOSWITCH section used for declaring global BSS variables.
148 May be null. */
149 section *bss_noswitch_section;
151 /* The section that holds the main exception table, when known. The section
152 is set either by the target's init_sections hook or by the first call to
153 switch_to_exception_section. */
154 section *exception_section;
156 /* The section that holds the DWARF2 frame unwind information, when known.
157 The section is set either by the target's init_sections hook or by the
158 first call to switch_to_eh_frame_section. */
159 section *eh_frame_section;
161 /* asm_out_file's current section. This is NULL if no section has yet
162 been selected or if we lose track of what the current section is. */
163 section *in_section;
165 /* True if code for the current function is currently being directed
166 at the cold section. */
167 bool in_cold_section_p;
169 /* A linked list of all the unnamed sections. */
170 static GTY(()) section *unnamed_sections;
172 /* Return a nonzero value if DECL has a section attribute. */
173 #define IN_NAMED_SECTION(DECL) \
174 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \
175 && DECL_SECTION_NAME (DECL) != NULL)
177 /* Hash table of named sections. */
178 static GTY((param_is (section))) htab_t section_htab;
180 /* A table of object_blocks, indexed by section. */
181 static GTY((param_is (struct object_block))) htab_t object_block_htab;
183 /* The next number to use for internal anchor labels. */
184 static GTY(()) int anchor_labelno;
186 /* A pool of constants that can be shared between functions. */
187 static GTY(()) struct rtx_constant_pool *shared_constant_pool;
189 /* Helper routines for maintaining section_htab. */
191 static int
192 section_entry_eq (const void *p1, const void *p2)
194 const section *old = (const section *) p1;
195 const char *new_name = (const char *) p2;
197 return strcmp (old->named.name, new_name) == 0;
200 static hashval_t
201 section_entry_hash (const void *p)
203 const section *old = (const section *) p;
204 return htab_hash_string (old->named.name);
207 /* Return a hash value for section SECT. */
209 static hashval_t
210 hash_section (section *sect)
212 if (sect->common.flags & SECTION_NAMED)
213 return htab_hash_string (sect->named.name);
214 return sect->common.flags;
217 /* Helper routines for maintaining object_block_htab. */
219 static int
220 object_block_entry_eq (const void *p1, const void *p2)
222 const struct object_block *old = (const struct object_block *) p1;
223 const section *new_section = (const section *) p2;
225 return old->sect == new_section;
228 static hashval_t
229 object_block_entry_hash (const void *p)
231 const struct object_block *old = (const struct object_block *) p;
232 return hash_section (old->sect);
235 /* Return a new unnamed section with the given fields. */
237 section *
238 get_unnamed_section (unsigned int flags, void (*callback) (const void *),
239 const void *data)
241 section *sect;
243 sect = ggc_alloc<section> ();
244 sect->unnamed.common.flags = flags | SECTION_UNNAMED;
245 sect->unnamed.callback = callback;
246 sect->unnamed.data = data;
247 sect->unnamed.next = unnamed_sections;
249 unnamed_sections = sect;
250 return sect;
253 /* Return a SECTION_NOSWITCH section with the given fields. */
255 static section *
256 get_noswitch_section (unsigned int flags, noswitch_section_callback callback)
258 section *sect;
260 sect = ggc_alloc<section> ();
261 sect->noswitch.common.flags = flags | SECTION_NOSWITCH;
262 sect->noswitch.callback = callback;
264 return sect;
267 /* Return the named section structure associated with NAME. Create
268 a new section with the given fields if no such structure exists. */
270 section *
271 get_section (const char *name, unsigned int flags, tree decl)
273 section *sect, **slot;
275 slot = (section **)
276 htab_find_slot_with_hash (section_htab, name,
277 htab_hash_string (name), INSERT);
278 flags |= SECTION_NAMED;
279 if (*slot == NULL)
281 sect = ggc_alloc<section> ();
282 sect->named.common.flags = flags;
283 sect->named.name = ggc_strdup (name);
284 sect->named.decl = decl;
285 *slot = sect;
287 else
289 sect = *slot;
290 if ((sect->common.flags & ~SECTION_DECLARED) != flags
291 && ((sect->common.flags | flags) & SECTION_OVERRIDE) == 0)
293 /* It is fine if one of the section flags is
294 SECTION_WRITE | SECTION_RELRO and the other has none of these
295 flags (i.e. read-only) in named sections and either the
296 section hasn't been declared yet or has been declared as writable.
297 In that case just make sure the resulting flags are
298 SECTION_WRITE | SECTION_RELRO, ie. writable only because of
299 relocations. */
300 if (((sect->common.flags ^ flags) & (SECTION_WRITE | SECTION_RELRO))
301 == (SECTION_WRITE | SECTION_RELRO)
302 && (sect->common.flags
303 & ~(SECTION_DECLARED | SECTION_WRITE | SECTION_RELRO))
304 == (flags & ~(SECTION_WRITE | SECTION_RELRO))
305 && ((sect->common.flags & SECTION_DECLARED) == 0
306 || (sect->common.flags & SECTION_WRITE)))
308 sect->common.flags |= (SECTION_WRITE | SECTION_RELRO);
309 return sect;
311 /* Sanity check user variables for flag changes. */
312 if (sect->named.decl != NULL
313 && DECL_P (sect->named.decl)
314 && decl != sect->named.decl)
316 if (decl != NULL && DECL_P (decl))
317 error ("%+D causes a section type conflict with %D",
318 decl, sect->named.decl);
319 else
320 error ("section type conflict with %D", sect->named.decl);
321 inform (DECL_SOURCE_LOCATION (sect->named.decl),
322 "%qD was declared here", sect->named.decl);
324 else if (decl != NULL && DECL_P (decl))
325 error ("%+D causes a section type conflict", decl);
326 else
327 error ("section type conflict");
328 /* Make sure we don't error about one section multiple times. */
329 sect->common.flags |= SECTION_OVERRIDE;
332 return sect;
335 /* Return true if the current compilation mode benefits from having
336 objects grouped into blocks. */
338 static bool
339 use_object_blocks_p (void)
341 return flag_section_anchors;
344 /* Return the object_block structure for section SECT. Create a new
345 structure if we haven't created one already. Return null if SECT
346 itself is null. */
348 static struct object_block *
349 get_block_for_section (section *sect)
351 struct object_block *block;
352 void **slot;
354 if (sect == NULL)
355 return NULL;
357 slot = htab_find_slot_with_hash (object_block_htab, sect,
358 hash_section (sect), INSERT);
359 block = (struct object_block *) *slot;
360 if (block == NULL)
362 block = ggc_cleared_alloc<object_block> ();
363 block->sect = sect;
364 *slot = block;
366 return block;
369 /* Create a symbol with label LABEL and place it at byte offset
370 OFFSET in BLOCK. OFFSET can be negative if the symbol's offset
371 is not yet known. LABEL must be a garbage-collected string. */
373 static rtx
374 create_block_symbol (const char *label, struct object_block *block,
375 HOST_WIDE_INT offset)
377 rtx symbol;
378 unsigned int size;
380 /* Create the extended SYMBOL_REF. */
381 size = RTX_HDR_SIZE + sizeof (struct block_symbol);
382 symbol = (rtx) ggc_internal_alloc (size);
384 /* Initialize the normal SYMBOL_REF fields. */
385 memset (symbol, 0, size);
386 PUT_CODE (symbol, SYMBOL_REF);
387 PUT_MODE (symbol, Pmode);
388 XSTR (symbol, 0) = label;
389 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_HAS_BLOCK_INFO;
391 /* Initialize the block_symbol stuff. */
392 SYMBOL_REF_BLOCK (symbol) = block;
393 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
395 return symbol;
398 /* Return a section with a particular name and with whatever SECTION_*
399 flags section_type_flags deems appropriate. The name of the section
400 is taken from NAME if nonnull, otherwise it is taken from DECL's
401 DECL_SECTION_NAME. DECL is the decl associated with the section
402 (see the section comment for details) and RELOC is as for
403 section_type_flags. */
405 section *
406 get_named_section (tree decl, const char *name, int reloc)
408 unsigned int flags;
410 if (name == NULL)
412 gcc_assert (decl && DECL_P (decl) && DECL_SECTION_NAME (decl));
413 name = DECL_SECTION_NAME (decl);
416 flags = targetm.section_type_flags (decl, name, reloc);
417 return get_section (name, flags, decl);
420 /* Worker for resolve_unique_section. */
422 static bool
423 set_implicit_section (struct symtab_node *n, void *data ATTRIBUTE_UNUSED)
425 n->implicit_section = true;
426 return false;
429 /* If required, set DECL_SECTION_NAME to a unique name. */
431 void
432 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
433 int flag_function_or_data_sections)
435 if (DECL_SECTION_NAME (decl) == NULL
436 && targetm_common.have_named_sections
437 && (flag_function_or_data_sections
438 || DECL_COMDAT_GROUP (decl)))
440 targetm.asm_out.unique_section (decl, reloc);
441 if (DECL_SECTION_NAME (decl))
442 symtab_node::get (decl)->call_for_symbol_and_aliases
443 (set_implicit_section, NULL, true);
447 #ifdef BSS_SECTION_ASM_OP
449 #ifdef ASM_OUTPUT_ALIGNED_BSS
451 /* Utility function for targets to use in implementing
452 ASM_OUTPUT_ALIGNED_BSS.
453 ??? It is believed that this function will work in most cases so such
454 support is localized here. */
456 static void
457 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
458 const char *name, unsigned HOST_WIDE_INT size,
459 int align)
461 switch_to_section (bss_section);
462 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
463 #ifdef ASM_DECLARE_OBJECT_NAME
464 last_assemble_variable_decl = decl;
465 ASM_DECLARE_OBJECT_NAME (file, name, decl);
466 #else
467 /* Standard thing is just output label for the object. */
468 ASM_OUTPUT_LABEL (file, name);
469 #endif /* ASM_DECLARE_OBJECT_NAME */
470 ASM_OUTPUT_SKIP (file, size ? size : 1);
473 #endif
475 #endif /* BSS_SECTION_ASM_OP */
477 #ifndef USE_SELECT_SECTION_FOR_FUNCTIONS
478 /* Return the hot section for function DECL. Return text_section for
479 null DECLs. */
481 static section *
482 hot_function_section (tree decl)
484 if (decl != NULL_TREE
485 && DECL_SECTION_NAME (decl) != NULL
486 && targetm_common.have_named_sections)
487 return get_named_section (decl, NULL, 0);
488 else
489 return text_section;
491 #endif
493 /* Return section for TEXT_SECTION_NAME if DECL or DECL_SECTION_NAME (DECL)
494 is NULL.
496 When DECL_SECTION_NAME is non-NULL and it is implicit section and
497 NAMED_SECTION_SUFFIX is non-NULL, then produce section called
498 concatenate the name with NAMED_SECTION_SUFFIX.
499 Otherwise produce "TEXT_SECTION_NAME.IMPLICIT_NAME". */
501 section *
502 get_named_text_section (tree decl,
503 const char *text_section_name,
504 const char *named_section_suffix)
506 if (decl && DECL_SECTION_NAME (decl))
508 if (named_section_suffix)
510 const char *dsn = DECL_SECTION_NAME (decl);
511 const char *stripped_name;
512 char *name, *buffer;
514 name = (char *) alloca (strlen (dsn) + 1);
515 memcpy (name, dsn,
516 strlen (dsn) + 1);
518 stripped_name = targetm.strip_name_encoding (name);
520 buffer = ACONCAT ((stripped_name, named_section_suffix, NULL));
521 return get_named_section (decl, buffer, 0);
523 else if (symtab_node::get (decl)->implicit_section)
525 const char *name;
527 /* Do not try to split gnu_linkonce functions. This gets somewhat
528 slipperly. */
529 if (DECL_COMDAT_GROUP (decl) && !HAVE_COMDAT_GROUP)
530 return NULL;
531 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
532 name = targetm.strip_name_encoding (name);
533 return get_named_section (decl, ACONCAT ((text_section_name, ".",
534 name, NULL)), 0);
536 else
537 return NULL;
539 return get_named_section (decl, text_section_name, 0);
542 /* Choose named function section based on its frequency. */
544 section *
545 default_function_section (tree decl, enum node_frequency freq,
546 bool startup, bool exit)
548 #if defined HAVE_LD_EH_GC_SECTIONS && defined HAVE_LD_EH_GC_SECTIONS_BUG
549 /* Old GNU linkers have buggy --gc-section support, which sometimes
550 results in .gcc_except_table* sections being garbage collected. */
551 if (decl
552 && symtab_node::get (decl)->implicit_section)
553 return NULL;
554 #endif
556 if (!flag_reorder_functions
557 || !targetm_common.have_named_sections)
558 return NULL;
559 /* Startup code should go to startup subsection unless it is
560 unlikely executed (this happens especially with function splitting
561 where we can split away unnecessary parts of static constructors. */
562 if (startup && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
564 /* If we do have a profile or(and) LTO phase is executed, we do not need
565 these ELF section. */
566 if (!in_lto_p || !flag_profile_values)
567 return get_named_text_section (decl, ".text.startup", NULL);
568 else
569 return NULL;
572 /* Similarly for exit. */
573 if (exit && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
574 return get_named_text_section (decl, ".text.exit", NULL);
576 /* Group cold functions together, similarly for hot code. */
577 switch (freq)
579 case NODE_FREQUENCY_UNLIKELY_EXECUTED:
580 return get_named_text_section (decl, ".text.unlikely", NULL);
581 case NODE_FREQUENCY_HOT:
582 /* If we do have a profile or(and) LTO phase is executed, we do not need
583 these ELF section. */
584 if (!in_lto_p || !flag_profile_values)
585 return get_named_text_section (decl, ".text.hot", NULL);
586 default:
587 return NULL;
591 /* Return the section for function DECL.
593 If DECL is NULL_TREE, return the text section. We can be passed
594 NULL_TREE under some circumstances by dbxout.c at least.
596 If FORCE_COLD is true, return cold function section ignoring
597 the frequency info of cgraph_node. */
599 static section *
600 function_section_1 (tree decl, bool force_cold)
602 section *section = NULL;
603 enum node_frequency freq = NODE_FREQUENCY_NORMAL;
604 bool startup = false, exit = false;
606 if (decl)
608 struct cgraph_node *node = cgraph_node::get (decl);
610 if (node)
612 freq = node->frequency;
613 startup = node->only_called_at_startup;
614 exit = node->only_called_at_exit;
617 if (force_cold)
618 freq = NODE_FREQUENCY_UNLIKELY_EXECUTED;
620 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
621 if (decl != NULL_TREE
622 && DECL_SECTION_NAME (decl) != NULL)
624 if (targetm.asm_out.function_section)
625 section = targetm.asm_out.function_section (decl, freq,
626 startup, exit);
627 if (section)
628 return section;
629 return get_named_section (decl, NULL, 0);
631 else
632 return targetm.asm_out.select_section
633 (decl, freq == NODE_FREQUENCY_UNLIKELY_EXECUTED,
634 DECL_ALIGN (decl));
635 #else
636 if (targetm.asm_out.function_section)
637 section = targetm.asm_out.function_section (decl, freq, startup, exit);
638 if (section)
639 return section;
640 return hot_function_section (decl);
641 #endif
644 /* Return the section for function DECL.
646 If DECL is NULL_TREE, return the text section. We can be passed
647 NULL_TREE under some circumstances by dbxout.c at least. */
649 section *
650 function_section (tree decl)
652 /* Handle cases where function splitting code decides
653 to put function entry point into unlikely executed section
654 despite the fact that the function itself is not cold
655 (i.e. it is called rarely but contains a hot loop that is
656 better to live in hot subsection for the code locality). */
657 return function_section_1 (decl,
658 first_function_block_is_cold);
661 /* Return the section for the current function, take IN_COLD_SECTION_P
662 into account. */
664 section *
665 current_function_section (void)
667 return function_section_1 (current_function_decl, in_cold_section_p);
670 /* Tell assembler to switch to unlikely-to-be-executed text section. */
672 section *
673 unlikely_text_section (void)
675 return function_section_1 (current_function_decl, true);
678 /* When called within a function context, return true if the function
679 has been assigned a cold text section and if SECT is that section.
680 When called outside a function context, return true if SECT is the
681 default cold section. */
683 bool
684 unlikely_text_section_p (section *sect)
686 return sect == function_section_1 (current_function_decl, true);
689 /* Return the read-only data section associated with function DECL. */
691 section *
692 default_function_rodata_section (tree decl)
694 if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
696 const char *name = DECL_SECTION_NAME (decl);
698 if (DECL_COMDAT_GROUP (decl) && HAVE_COMDAT_GROUP)
700 const char *dot;
701 size_t len;
702 char* rname;
704 dot = strchr (name + 1, '.');
705 if (!dot)
706 dot = name;
707 len = strlen (dot) + 8;
708 rname = (char *) alloca (len);
710 strcpy (rname, ".rodata");
711 strcat (rname, dot);
712 return get_section (rname, SECTION_LINKONCE, decl);
714 /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo. */
715 else if (DECL_COMDAT_GROUP (decl)
716 && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
718 size_t len = strlen (name) + 1;
719 char *rname = (char *) alloca (len);
721 memcpy (rname, name, len);
722 rname[14] = 'r';
723 return get_section (rname, SECTION_LINKONCE, decl);
725 /* For .text.foo we want to use .rodata.foo. */
726 else if (flag_function_sections && flag_data_sections
727 && strncmp (name, ".text.", 6) == 0)
729 size_t len = strlen (name) + 1;
730 char *rname = (char *) alloca (len + 2);
732 memcpy (rname, ".rodata", 7);
733 memcpy (rname + 7, name + 5, len - 5);
734 return get_section (rname, 0, decl);
738 return readonly_data_section;
741 /* Return the read-only data section associated with function DECL
742 for targets where that section should be always the single
743 readonly data section. */
745 section *
746 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
748 return readonly_data_section;
751 /* Return the section to use for string merging. */
753 static section *
754 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
755 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
756 unsigned int flags ATTRIBUTE_UNUSED)
758 HOST_WIDE_INT len;
760 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
761 && TREE_CODE (decl) == STRING_CST
762 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
763 && align <= 256
764 && (len = int_size_in_bytes (TREE_TYPE (decl))) > 0
765 && TREE_STRING_LENGTH (decl) >= len)
767 enum machine_mode mode;
768 unsigned int modesize;
769 const char *str;
770 HOST_WIDE_INT i;
771 int j, unit;
772 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
773 char *name = (char *) alloca (strlen (prefix) + 30);
775 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
776 modesize = GET_MODE_BITSIZE (mode);
777 if (modesize >= 8 && modesize <= 256
778 && (modesize & (modesize - 1)) == 0)
780 if (align < modesize)
781 align = modesize;
783 str = TREE_STRING_POINTER (decl);
784 unit = GET_MODE_SIZE (mode);
786 /* Check for embedded NUL characters. */
787 for (i = 0; i < len; i += unit)
789 for (j = 0; j < unit; j++)
790 if (str[i + j] != '\0')
791 break;
792 if (j == unit)
793 break;
795 if (i == len - unit)
797 sprintf (name, "%s.str%d.%d", prefix,
798 modesize / 8, (int) (align / 8));
799 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
800 return get_section (name, flags, NULL);
805 return readonly_data_section;
808 /* Return the section to use for constant merging. */
810 section *
811 mergeable_constant_section (enum machine_mode mode ATTRIBUTE_UNUSED,
812 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
813 unsigned int flags ATTRIBUTE_UNUSED)
815 unsigned int modesize = GET_MODE_BITSIZE (mode);
817 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
818 && mode != VOIDmode
819 && mode != BLKmode
820 && modesize <= align
821 && align >= 8
822 && align <= 256
823 && (align & (align - 1)) == 0)
825 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
826 char *name = (char *) alloca (strlen (prefix) + 30);
828 sprintf (name, "%s.cst%d", prefix, (int) (align / 8));
829 flags |= (align / 8) | SECTION_MERGE;
830 return get_section (name, flags, NULL);
832 return readonly_data_section;
835 /* Given NAME, a putative register name, discard any customary prefixes. */
837 static const char *
838 strip_reg_name (const char *name)
840 #ifdef REGISTER_PREFIX
841 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
842 name += strlen (REGISTER_PREFIX);
843 #endif
844 if (name[0] == '%' || name[0] == '#')
845 name++;
846 return name;
849 /* The user has asked for a DECL to have a particular name. Set (or
850 change) it in such a way that we don't prefix an underscore to
851 it. */
852 void
853 set_user_assembler_name (tree decl, const char *name)
855 char *starred = (char *) alloca (strlen (name) + 2);
856 starred[0] = '*';
857 strcpy (starred + 1, name);
858 symtab->change_decl_assembler_name (decl, get_identifier (starred));
859 SET_DECL_RTL (decl, NULL_RTX);
862 /* Decode an `asm' spec for a declaration as a register name.
863 Return the register number, or -1 if nothing specified,
864 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
865 or -3 if ASMSPEC is `cc' and is not recognized,
866 or -4 if ASMSPEC is `memory' and is not recognized.
867 Accept an exact spelling or a decimal number.
868 Prefixes such as % are optional. */
871 decode_reg_name_and_count (const char *asmspec, int *pnregs)
873 /* Presume just one register is clobbered. */
874 *pnregs = 1;
876 if (asmspec != 0)
878 int i;
880 /* Get rid of confusing prefixes. */
881 asmspec = strip_reg_name (asmspec);
883 /* Allow a decimal number as a "register name". */
884 for (i = strlen (asmspec) - 1; i >= 0; i--)
885 if (! ISDIGIT (asmspec[i]))
886 break;
887 if (asmspec[0] != 0 && i < 0)
889 i = atoi (asmspec);
890 if (i < FIRST_PSEUDO_REGISTER && i >= 0)
891 return i;
892 else
893 return -2;
896 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
897 if (reg_names[i][0]
898 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
899 return i;
901 #ifdef OVERLAPPING_REGISTER_NAMES
903 static const struct
905 const char *const name;
906 const int number;
907 const int nregs;
908 } table[] = OVERLAPPING_REGISTER_NAMES;
910 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
911 if (table[i].name[0]
912 && ! strcmp (asmspec, table[i].name))
914 *pnregs = table[i].nregs;
915 return table[i].number;
918 #endif /* OVERLAPPING_REGISTER_NAMES */
920 #ifdef ADDITIONAL_REGISTER_NAMES
922 static const struct { const char *const name; const int number; } table[]
923 = ADDITIONAL_REGISTER_NAMES;
925 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
926 if (table[i].name[0]
927 && ! strcmp (asmspec, table[i].name))
928 return table[i].number;
930 #endif /* ADDITIONAL_REGISTER_NAMES */
932 if (!strcmp (asmspec, "memory"))
933 return -4;
935 if (!strcmp (asmspec, "cc"))
936 return -3;
938 return -2;
941 return -1;
945 decode_reg_name (const char *name)
947 int count;
948 return decode_reg_name_and_count (name, &count);
952 /* Return true if DECL's initializer is suitable for a BSS section. */
954 bool
955 bss_initializer_p (const_tree decl)
957 return (DECL_INITIAL (decl) == NULL
958 /* In LTO we have no errors in program; error_mark_node is used
959 to mark offlined constructors. */
960 || (DECL_INITIAL (decl) == error_mark_node
961 && !in_lto_p)
962 || (flag_zero_initialized_in_bss
963 /* Leave constant zeroes in .rodata so they
964 can be shared. */
965 && !TREE_READONLY (decl)
966 && initializer_zerop (DECL_INITIAL (decl))));
969 /* Compute the alignment of variable specified by DECL.
970 DONT_OUTPUT_DATA is from assemble_variable. */
972 void
973 align_variable (tree decl, bool dont_output_data)
975 unsigned int align = DECL_ALIGN (decl);
977 /* In the case for initialing an array whose length isn't specified,
978 where we have not yet been able to do the layout,
979 figure out the proper alignment now. */
980 if (dont_output_data && DECL_SIZE (decl) == 0
981 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
982 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
984 /* Some object file formats have a maximum alignment which they support.
985 In particular, a.out format supports a maximum alignment of 4. */
986 if (align > MAX_OFILE_ALIGNMENT)
988 error ("alignment of %q+D is greater than maximum object "
989 "file alignment %d", decl,
990 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
991 align = MAX_OFILE_ALIGNMENT;
994 if (! DECL_USER_ALIGN (decl))
996 #ifdef DATA_ABI_ALIGNMENT
997 unsigned int data_abi_align
998 = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
999 /* For backwards compatibility, don't assume the ABI alignment for
1000 TLS variables. */
1001 if (! DECL_THREAD_LOCAL_P (decl) || data_abi_align <= BITS_PER_WORD)
1002 align = data_abi_align;
1003 #endif
1005 /* On some machines, it is good to increase alignment sometimes.
1006 But as DECL_ALIGN is used both for actually emitting the variable
1007 and for code accessing the variable as guaranteed alignment, we
1008 can only increase the alignment if it is a performance optimization
1009 if the references to it must bind to the current definition. */
1010 if (decl_binds_to_current_def_p (decl)
1011 && !DECL_VIRTUAL_P (decl))
1013 #ifdef DATA_ALIGNMENT
1014 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1015 /* Don't increase alignment too much for TLS variables - TLS space
1016 is too precious. */
1017 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1018 align = data_align;
1019 #endif
1020 #ifdef CONSTANT_ALIGNMENT
1021 if (DECL_INITIAL (decl) != 0
1022 /* In LTO we have no errors in program; error_mark_node is used
1023 to mark offlined constructors. */
1024 && (in_lto_p || DECL_INITIAL (decl) != error_mark_node))
1026 unsigned int const_align
1027 = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
1028 /* Don't increase alignment too much for TLS variables - TLS
1029 space is too precious. */
1030 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1031 align = const_align;
1033 #endif
1037 /* Reset the alignment in case we have made it tighter, so we can benefit
1038 from it in get_pointer_alignment. */
1039 DECL_ALIGN (decl) = align;
1042 /* Return DECL_ALIGN (decl), possibly increased for optimization purposes
1043 beyond what align_variable returned. */
1045 static unsigned int
1046 get_variable_align (tree decl)
1048 unsigned int align = DECL_ALIGN (decl);
1050 /* For user aligned vars or static vars align_variable already did
1051 everything. */
1052 if (DECL_USER_ALIGN (decl) || !TREE_PUBLIC (decl))
1053 return align;
1055 #ifdef DATA_ABI_ALIGNMENT
1056 if (DECL_THREAD_LOCAL_P (decl))
1057 align = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1058 #endif
1060 /* For decls that bind to the current definition, align_variable
1061 did also everything, except for not assuming ABI required alignment
1062 of TLS variables. For other vars, increase the alignment here
1063 as an optimization. */
1064 if (!decl_binds_to_current_def_p (decl))
1066 /* On some machines, it is good to increase alignment sometimes. */
1067 #ifdef DATA_ALIGNMENT
1068 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1069 /* Don't increase alignment too much for TLS variables - TLS space
1070 is too precious. */
1071 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1072 align = data_align;
1073 #endif
1074 #ifdef CONSTANT_ALIGNMENT
1075 if (DECL_INITIAL (decl) != 0
1076 /* In LTO we have no errors in program; error_mark_node is used
1077 to mark offlined constructors. */
1078 && (in_lto_p || DECL_INITIAL (decl) != error_mark_node))
1080 unsigned int const_align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl),
1081 align);
1082 /* Don't increase alignment too much for TLS variables - TLS space
1083 is too precious. */
1084 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1085 align = const_align;
1087 #endif
1090 return align;
1093 /* Return the section into which the given VAR_DECL or CONST_DECL
1094 should be placed. PREFER_NOSWITCH_P is true if a noswitch
1095 section should be used wherever possible. */
1097 section *
1098 get_variable_section (tree decl, bool prefer_noswitch_p)
1100 addr_space_t as = ADDR_SPACE_GENERIC;
1101 int reloc;
1102 varpool_node *vnode = varpool_node::get (decl);
1103 if (vnode)
1105 vnode = vnode->ultimate_alias_target ();
1106 decl = vnode->decl;
1109 if (TREE_TYPE (decl) != error_mark_node)
1110 as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1112 /* We need the constructor to figure out reloc flag. */
1113 if (vnode)
1114 vnode->get_constructor ();
1116 if (DECL_COMMON (decl))
1118 /* If the decl has been given an explicit section name, or it resides
1119 in a non-generic address space, then it isn't common, and shouldn't
1120 be handled as such. */
1121 gcc_assert (DECL_SECTION_NAME (decl) == NULL
1122 && ADDR_SPACE_GENERIC_P (as));
1123 if (DECL_THREAD_LOCAL_P (decl))
1124 return tls_comm_section;
1125 else if (TREE_PUBLIC (decl) && bss_initializer_p (decl))
1126 return comm_section;
1129 if (DECL_INITIAL (decl) == error_mark_node)
1130 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1131 else if (DECL_INITIAL (decl))
1132 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1133 else
1134 reloc = 0;
1136 resolve_unique_section (decl, reloc, flag_data_sections);
1137 if (IN_NAMED_SECTION (decl))
1138 return get_named_section (decl, NULL, reloc);
1140 if (ADDR_SPACE_GENERIC_P (as)
1141 && !DECL_THREAD_LOCAL_P (decl)
1142 && !(prefer_noswitch_p && targetm.have_switchable_bss_sections)
1143 && bss_initializer_p (decl))
1145 if (!TREE_PUBLIC (decl)
1146 && !((flag_sanitize & SANITIZE_ADDRESS)
1147 && asan_protect_global (decl)))
1148 return lcomm_section;
1149 if (bss_noswitch_section)
1150 return bss_noswitch_section;
1153 return targetm.asm_out.select_section (decl, reloc,
1154 get_variable_align (decl));
1157 /* Return the block into which object_block DECL should be placed. */
1159 static struct object_block *
1160 get_block_for_decl (tree decl)
1162 section *sect;
1164 if (TREE_CODE (decl) == VAR_DECL)
1166 /* The object must be defined in this translation unit. */
1167 if (DECL_EXTERNAL (decl))
1168 return NULL;
1170 /* There's no point using object blocks for something that is
1171 isolated by definition. */
1172 if (DECL_COMDAT_GROUP (decl))
1173 return NULL;
1176 /* We can only calculate block offsets if the decl has a known
1177 constant size. */
1178 if (DECL_SIZE_UNIT (decl) == NULL)
1179 return NULL;
1180 if (!tree_fits_uhwi_p (DECL_SIZE_UNIT (decl)))
1181 return NULL;
1183 /* Find out which section should contain DECL. We cannot put it into
1184 an object block if it requires a standalone definition. */
1185 if (TREE_CODE (decl) == VAR_DECL)
1186 align_variable (decl, 0);
1187 sect = get_variable_section (decl, true);
1188 if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
1189 return NULL;
1191 return get_block_for_section (sect);
1194 /* Make sure block symbol SYMBOL is in block BLOCK. */
1196 static void
1197 change_symbol_block (rtx symbol, struct object_block *block)
1199 if (block != SYMBOL_REF_BLOCK (symbol))
1201 gcc_assert (SYMBOL_REF_BLOCK_OFFSET (symbol) < 0);
1202 SYMBOL_REF_BLOCK (symbol) = block;
1206 /* Return true if it is possible to put DECL in an object_block. */
1208 static bool
1209 use_blocks_for_decl_p (tree decl)
1211 struct symtab_node *snode;
1213 /* Only data DECLs can be placed into object blocks. */
1214 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != CONST_DECL)
1215 return false;
1217 /* Detect decls created by dw2_force_const_mem. Such decls are
1218 special because DECL_INITIAL doesn't specify the decl's true value.
1219 dw2_output_indirect_constants will instead call assemble_variable
1220 with dont_output_data set to 1 and then print the contents itself. */
1221 if (DECL_INITIAL (decl) == decl)
1222 return false;
1224 /* If this decl is an alias, then we don't want to emit a
1225 definition. */
1226 if (TREE_CODE (decl) == VAR_DECL
1227 && (snode = symtab_node::get (decl)) != NULL
1228 && snode->alias)
1229 return false;
1231 return targetm.use_blocks_for_decl_p (decl);
1234 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
1235 have static storage duration. In other words, it should not be an
1236 automatic variable, including PARM_DECLs.
1238 There is, however, one exception: this function handles variables
1239 explicitly placed in a particular register by the user.
1241 This is never called for PARM_DECL nodes. */
1243 void
1244 make_decl_rtl (tree decl)
1246 const char *name = 0;
1247 int reg_number;
1248 rtx x;
1250 /* Check that we are not being given an automatic variable. */
1251 gcc_assert (TREE_CODE (decl) != PARM_DECL
1252 && TREE_CODE (decl) != RESULT_DECL);
1254 /* A weak alias has TREE_PUBLIC set but not the other bits. */
1255 gcc_assert (TREE_CODE (decl) != VAR_DECL
1256 || TREE_STATIC (decl)
1257 || TREE_PUBLIC (decl)
1258 || DECL_EXTERNAL (decl)
1259 || DECL_REGISTER (decl));
1261 /* And that we were not given a type or a label. */
1262 gcc_assert (TREE_CODE (decl) != TYPE_DECL
1263 && TREE_CODE (decl) != LABEL_DECL);
1265 /* For a duplicate declaration, we can be called twice on the
1266 same DECL node. Don't discard the RTL already made. */
1267 if (DECL_RTL_SET_P (decl))
1269 /* If the old RTL had the wrong mode, fix the mode. */
1270 x = DECL_RTL (decl);
1271 if (GET_MODE (x) != DECL_MODE (decl))
1272 SET_DECL_RTL (decl, adjust_address_nv (x, DECL_MODE (decl), 0));
1274 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1275 return;
1277 /* ??? Another way to do this would be to maintain a hashed
1278 table of such critters. Instead of adding stuff to a DECL
1279 to give certain attributes to it, we could use an external
1280 hash map from DECL to set of attributes. */
1282 /* Let the target reassign the RTL if it wants.
1283 This is necessary, for example, when one machine specific
1284 decl attribute overrides another. */
1285 targetm.encode_section_info (decl, DECL_RTL (decl), false);
1287 /* If the symbol has a SYMBOL_REF_BLOCK field, update it based
1288 on the new decl information. */
1289 if (MEM_P (x)
1290 && GET_CODE (XEXP (x, 0)) == SYMBOL_REF
1291 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (x, 0)))
1292 change_symbol_block (XEXP (x, 0), get_block_for_decl (decl));
1294 return;
1297 /* If this variable belongs to the global constant pool, retrieve the
1298 pre-computed RTL or recompute it in LTO mode. */
1299 if (TREE_CODE (decl) == VAR_DECL && DECL_IN_CONSTANT_POOL (decl))
1301 SET_DECL_RTL (decl, output_constant_def (DECL_INITIAL (decl), 1));
1302 return;
1305 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
1307 if (name[0] != '*' && TREE_CODE (decl) != FUNCTION_DECL
1308 && DECL_REGISTER (decl))
1310 error ("register name not specified for %q+D", decl);
1312 else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1314 const char *asmspec = name+1;
1315 enum machine_mode mode = DECL_MODE (decl);
1316 reg_number = decode_reg_name (asmspec);
1317 /* First detect errors in declaring global registers. */
1318 if (reg_number == -1)
1319 error ("register name not specified for %q+D", decl);
1320 else if (reg_number < 0)
1321 error ("invalid register name for %q+D", decl);
1322 else if (mode == BLKmode)
1323 error ("data type of %q+D isn%'t suitable for a register",
1324 decl);
1325 else if (!in_hard_reg_set_p (accessible_reg_set, mode, reg_number))
1326 error ("the register specified for %q+D cannot be accessed"
1327 " by the current target", decl);
1328 else if (!in_hard_reg_set_p (operand_reg_set, mode, reg_number))
1329 error ("the register specified for %q+D is not general enough"
1330 " to be used as a register variable", decl);
1331 else if (!HARD_REGNO_MODE_OK (reg_number, mode))
1332 error ("register specified for %q+D isn%'t suitable for data type",
1333 decl);
1334 /* Now handle properly declared static register variables. */
1335 else
1337 int nregs;
1339 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
1341 DECL_INITIAL (decl) = 0;
1342 error ("global register variable has initial value");
1344 if (TREE_THIS_VOLATILE (decl))
1345 warning (OPT_Wvolatile_register_var,
1346 "optimization may eliminate reads and/or "
1347 "writes to register variables");
1349 /* If the user specified one of the eliminables registers here,
1350 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
1351 confused with that register and be eliminated. This usage is
1352 somewhat suspect... */
1354 SET_DECL_RTL (decl, gen_rtx_raw_REG (mode, reg_number));
1355 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
1356 REG_USERVAR_P (DECL_RTL (decl)) = 1;
1358 if (TREE_STATIC (decl))
1360 /* Make this register global, so not usable for anything
1361 else. */
1362 #ifdef ASM_DECLARE_REGISTER_GLOBAL
1363 name = IDENTIFIER_POINTER (DECL_NAME (decl));
1364 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
1365 #endif
1366 nregs = hard_regno_nregs[reg_number][mode];
1367 while (nregs > 0)
1368 globalize_reg (decl, reg_number + --nregs);
1371 /* As a register variable, it has no section. */
1372 return;
1374 /* Avoid internal errors from invalid register
1375 specifications. */
1376 SET_DECL_ASSEMBLER_NAME (decl, NULL_TREE);
1377 DECL_HARD_REGISTER (decl) = 0;
1378 return;
1380 /* Now handle ordinary static variables and functions (in memory).
1381 Also handle vars declared register invalidly. */
1382 else if (name[0] == '*')
1384 #ifdef REGISTER_PREFIX
1385 if (strlen (REGISTER_PREFIX) != 0)
1387 reg_number = decode_reg_name (name);
1388 if (reg_number >= 0 || reg_number == -3)
1389 error ("register name given for non-register variable %q+D", decl);
1391 #endif
1394 /* Specifying a section attribute on a variable forces it into a
1395 non-.bss section, and thus it cannot be common. */
1396 /* FIXME: In general this code should not be necessary because
1397 visibility pass is doing the same work. But notice_global_symbol
1398 is called early and it needs to make DECL_RTL to get the name.
1399 we take care of recomputing the DECL_RTL after visibility is changed. */
1400 if (TREE_CODE (decl) == VAR_DECL
1401 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl))
1402 && DECL_SECTION_NAME (decl) != NULL
1403 && DECL_INITIAL (decl) == NULL_TREE
1404 && DECL_COMMON (decl))
1405 DECL_COMMON (decl) = 0;
1407 /* Variables can't be both common and weak. */
1408 if (TREE_CODE (decl) == VAR_DECL && DECL_WEAK (decl))
1409 DECL_COMMON (decl) = 0;
1411 if (use_object_blocks_p () && use_blocks_for_decl_p (decl))
1412 x = create_block_symbol (name, get_block_for_decl (decl), -1);
1413 else
1415 enum machine_mode address_mode = Pmode;
1416 if (TREE_TYPE (decl) != error_mark_node)
1418 addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1419 address_mode = targetm.addr_space.address_mode (as);
1421 x = gen_rtx_SYMBOL_REF (address_mode, name);
1423 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
1424 SET_SYMBOL_REF_DECL (x, decl);
1426 x = gen_rtx_MEM (DECL_MODE (decl), x);
1427 if (TREE_CODE (decl) != FUNCTION_DECL)
1428 set_mem_attributes (x, decl, 1);
1429 SET_DECL_RTL (decl, x);
1431 /* Optionally set flags or add text to the name to record information
1432 such as that it is a function name.
1433 If the name is changed, the macro ASM_OUTPUT_LABELREF
1434 will have to know how to strip this information. */
1435 targetm.encode_section_info (decl, DECL_RTL (decl), true);
1438 /* Like make_decl_rtl, but inhibit creation of new alias sets when
1439 calling make_decl_rtl. Also, reset DECL_RTL before returning the
1440 rtl. */
1443 make_decl_rtl_for_debug (tree decl)
1445 unsigned int save_aliasing_flag;
1446 rtx rtl;
1448 if (DECL_RTL_SET_P (decl))
1449 return DECL_RTL (decl);
1451 /* Kludge alert! Somewhere down the call chain, make_decl_rtl will
1452 call new_alias_set. If running with -fcompare-debug, sometimes
1453 we do not want to create alias sets that will throw the alias
1454 numbers off in the comparison dumps. So... clearing
1455 flag_strict_aliasing will keep new_alias_set() from creating a
1456 new set. */
1457 save_aliasing_flag = flag_strict_aliasing;
1458 flag_strict_aliasing = 0;
1460 rtl = DECL_RTL (decl);
1461 /* Reset DECL_RTL back, as various parts of the compiler expects
1462 DECL_RTL set meaning it is actually going to be output. */
1463 SET_DECL_RTL (decl, NULL);
1465 flag_strict_aliasing = save_aliasing_flag;
1466 return rtl;
1469 /* Output a string of literal assembler code
1470 for an `asm' keyword used between functions. */
1472 void
1473 assemble_asm (tree string)
1475 const char *p;
1476 app_enable ();
1478 if (TREE_CODE (string) == ADDR_EXPR)
1479 string = TREE_OPERAND (string, 0);
1481 p = TREE_STRING_POINTER (string);
1482 fprintf (asm_out_file, "%s%s\n", p[0] == '\t' ? "" : "\t", p);
1485 /* Write the address of the entity given by SYMBOL to SEC. */
1486 void
1487 assemble_addr_to_section (rtx symbol, section *sec)
1489 switch_to_section (sec);
1490 assemble_align (POINTER_SIZE);
1491 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1494 /* Return the numbered .ctors.N (if CONSTRUCTOR_P) or .dtors.N (if
1495 not) section for PRIORITY. */
1496 section *
1497 get_cdtor_priority_section (int priority, bool constructor_p)
1499 char buf[16];
1501 /* ??? This only works reliably with the GNU linker. */
1502 sprintf (buf, "%s.%.5u",
1503 constructor_p ? ".ctors" : ".dtors",
1504 /* Invert the numbering so the linker puts us in the proper
1505 order; constructors are run from right to left, and the
1506 linker sorts in increasing order. */
1507 MAX_INIT_PRIORITY - priority);
1508 return get_section (buf, SECTION_WRITE, NULL);
1511 void
1512 default_named_section_asm_out_destructor (rtx symbol, int priority)
1514 section *sec;
1516 if (priority != DEFAULT_INIT_PRIORITY)
1517 sec = get_cdtor_priority_section (priority,
1518 /*constructor_p=*/false);
1519 else
1520 sec = get_section (".dtors", SECTION_WRITE, NULL);
1522 assemble_addr_to_section (symbol, sec);
1525 #ifdef DTORS_SECTION_ASM_OP
1526 void
1527 default_dtor_section_asm_out_destructor (rtx symbol,
1528 int priority ATTRIBUTE_UNUSED)
1530 assemble_addr_to_section (symbol, dtors_section);
1532 #endif
1534 void
1535 default_named_section_asm_out_constructor (rtx symbol, int priority)
1537 section *sec;
1539 if (priority != DEFAULT_INIT_PRIORITY)
1540 sec = get_cdtor_priority_section (priority,
1541 /*constructor_p=*/true);
1542 else
1543 sec = get_section (".ctors", SECTION_WRITE, NULL);
1545 assemble_addr_to_section (symbol, sec);
1548 #ifdef CTORS_SECTION_ASM_OP
1549 void
1550 default_ctor_section_asm_out_constructor (rtx symbol,
1551 int priority ATTRIBUTE_UNUSED)
1553 assemble_addr_to_section (symbol, ctors_section);
1555 #endif
1557 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1558 a nonzero value if the constant pool should be output before the
1559 start of the function, or a zero value if the pool should output
1560 after the end of the function. The default is to put it before the
1561 start. */
1563 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1564 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1565 #endif
1567 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1568 to be output to assembler.
1569 Set first_global_object_name and weak_global_object_name as appropriate. */
1571 void
1572 notice_global_symbol (tree decl)
1574 const char **type = &first_global_object_name;
1576 if (first_global_object_name
1577 || !TREE_PUBLIC (decl)
1578 || DECL_EXTERNAL (decl)
1579 || !DECL_NAME (decl)
1580 || (TREE_CODE (decl) != FUNCTION_DECL
1581 && (TREE_CODE (decl) != VAR_DECL
1582 || (DECL_COMMON (decl)
1583 && (DECL_INITIAL (decl) == 0
1584 || DECL_INITIAL (decl) == error_mark_node))))
1585 || !MEM_P (DECL_RTL (decl)))
1586 return;
1588 /* We win when global object is found, but it is useful to know about weak
1589 symbol as well so we can produce nicer unique names. */
1590 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl) || flag_shlib)
1591 type = &weak_global_object_name;
1593 if (!*type)
1595 const char *p;
1596 const char *name;
1597 rtx decl_rtl = DECL_RTL (decl);
1599 p = targetm.strip_name_encoding (XSTR (XEXP (decl_rtl, 0), 0));
1600 name = ggc_strdup (p);
1602 *type = name;
1606 /* If not using flag_reorder_blocks_and_partition, decide early whether the
1607 current function goes into the cold section, so that targets can use
1608 current_function_section during RTL expansion. DECL describes the
1609 function. */
1611 void
1612 decide_function_section (tree decl)
1614 first_function_block_is_cold = false;
1616 if (flag_reorder_blocks_and_partition)
1617 /* We will decide in assemble_start_function. */
1618 return;
1620 if (DECL_SECTION_NAME (decl))
1622 struct cgraph_node *node = cgraph_node::get (current_function_decl);
1623 /* Calls to function_section rely on first_function_block_is_cold
1624 being accurate. */
1625 first_function_block_is_cold = (node
1626 && node->frequency
1627 == NODE_FREQUENCY_UNLIKELY_EXECUTED);
1630 in_cold_section_p = first_function_block_is_cold;
1633 /* Output assembler code for the constant pool of a function and associated
1634 with defining the name of the function. DECL describes the function.
1635 NAME is the function's name. For the constant pool, we use the current
1636 constant pool data. */
1638 void
1639 assemble_start_function (tree decl, const char *fnname)
1641 int align;
1642 char tmp_label[100];
1643 bool hot_label_written = false;
1645 if (flag_reorder_blocks_and_partition)
1647 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTB", const_labelno);
1648 crtl->subsections.hot_section_label = ggc_strdup (tmp_label);
1649 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDB", const_labelno);
1650 crtl->subsections.cold_section_label = ggc_strdup (tmp_label);
1651 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTE", const_labelno);
1652 crtl->subsections.hot_section_end_label = ggc_strdup (tmp_label);
1653 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDE", const_labelno);
1654 crtl->subsections.cold_section_end_label = ggc_strdup (tmp_label);
1655 const_labelno++;
1657 else
1659 crtl->subsections.hot_section_label = NULL;
1660 crtl->subsections.cold_section_label = NULL;
1661 crtl->subsections.hot_section_end_label = NULL;
1662 crtl->subsections.cold_section_end_label = NULL;
1665 /* The following code does not need preprocessing in the assembler. */
1667 app_disable ();
1669 if (CONSTANT_POOL_BEFORE_FUNCTION)
1670 output_constant_pool (fnname, decl);
1672 /* Make sure the not and cold text (code) sections are properly
1673 aligned. This is necessary here in the case where the function
1674 has both hot and cold sections, because we don't want to re-set
1675 the alignment when the section switch happens mid-function. */
1677 if (flag_reorder_blocks_and_partition)
1679 first_function_block_is_cold = false;
1681 switch_to_section (unlikely_text_section ());
1682 assemble_align (DECL_ALIGN (decl));
1683 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_label);
1685 /* When the function starts with a cold section, we need to explicitly
1686 align the hot section and write out the hot section label.
1687 But if the current function is a thunk, we do not have a CFG. */
1688 if (!cfun->is_thunk
1689 && BB_PARTITION (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) == BB_COLD_PARTITION)
1691 switch_to_section (text_section);
1692 assemble_align (DECL_ALIGN (decl));
1693 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1694 hot_label_written = true;
1695 first_function_block_is_cold = true;
1697 in_cold_section_p = first_function_block_is_cold;
1701 /* Switch to the correct text section for the start of the function. */
1703 switch_to_section (function_section (decl));
1704 if (flag_reorder_blocks_and_partition
1705 && !hot_label_written)
1706 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1708 /* Tell assembler to move to target machine's alignment for functions. */
1709 align = floor_log2 (DECL_ALIGN (decl) / BITS_PER_UNIT);
1710 if (align > 0)
1712 ASM_OUTPUT_ALIGN (asm_out_file, align);
1715 /* Handle a user-specified function alignment.
1716 Note that we still need to align to DECL_ALIGN, as above,
1717 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1718 if (! DECL_USER_ALIGN (decl)
1719 && align_functions_log > align
1720 && optimize_function_for_speed_p (cfun))
1722 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1723 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1724 align_functions_log, align_functions - 1);
1725 #else
1726 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1727 #endif
1730 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1731 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1732 #endif
1734 if (!DECL_IGNORED_P (decl))
1735 (*debug_hooks->begin_function) (decl);
1737 /* Make function name accessible from other files, if appropriate. */
1739 if (TREE_PUBLIC (decl))
1741 notice_global_symbol (decl);
1743 globalize_decl (decl);
1745 maybe_assemble_visibility (decl);
1748 if (DECL_PRESERVE_P (decl))
1749 targetm.asm_out.mark_decl_preserved (fnname);
1751 /* Do any machine/system dependent processing of the function name. */
1752 #ifdef ASM_DECLARE_FUNCTION_NAME
1753 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1754 #else
1755 /* Standard thing is just output label for the function. */
1756 ASM_OUTPUT_FUNCTION_LABEL (asm_out_file, fnname, current_function_decl);
1757 #endif /* ASM_DECLARE_FUNCTION_NAME */
1759 if (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (decl)))
1760 saw_no_split_stack = true;
1763 /* Output assembler code associated with defining the size of the
1764 function. DECL describes the function. NAME is the function's name. */
1766 void
1767 assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED)
1769 #ifdef ASM_DECLARE_FUNCTION_SIZE
1770 /* We could have switched section in the middle of the function. */
1771 if (flag_reorder_blocks_and_partition)
1772 switch_to_section (function_section (decl));
1773 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1774 #endif
1775 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1777 output_constant_pool (fnname, decl);
1778 switch_to_section (function_section (decl)); /* need to switch back */
1780 /* Output labels for end of hot/cold text sections (to be used by
1781 debug info.) */
1782 if (flag_reorder_blocks_and_partition)
1784 section *save_text_section;
1786 save_text_section = in_section;
1787 switch_to_section (unlikely_text_section ());
1788 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label);
1789 if (first_function_block_is_cold)
1790 switch_to_section (text_section);
1791 else
1792 switch_to_section (function_section (decl));
1793 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label);
1794 switch_to_section (save_text_section);
1798 /* Assemble code to leave SIZE bytes of zeros. */
1800 void
1801 assemble_zeros (unsigned HOST_WIDE_INT size)
1803 /* Do no output if -fsyntax-only. */
1804 if (flag_syntax_only)
1805 return;
1807 #ifdef ASM_NO_SKIP_IN_TEXT
1808 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1809 so we must output 0s explicitly in the text section. */
1810 if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0)
1812 unsigned HOST_WIDE_INT i;
1813 for (i = 0; i < size; i++)
1814 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1816 else
1817 #endif
1818 if (size > 0)
1819 ASM_OUTPUT_SKIP (asm_out_file, size);
1822 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1824 void
1825 assemble_align (int align)
1827 if (align > BITS_PER_UNIT)
1829 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1833 /* Assemble a string constant with the specified C string as contents. */
1835 void
1836 assemble_string (const char *p, int size)
1838 int pos = 0;
1839 int maximum = 2000;
1841 /* If the string is very long, split it up. */
1843 while (pos < size)
1845 int thissize = size - pos;
1846 if (thissize > maximum)
1847 thissize = maximum;
1849 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1851 pos += thissize;
1852 p += thissize;
1857 /* A noswitch_section_callback for lcomm_section. */
1859 static bool
1860 emit_local (tree decl ATTRIBUTE_UNUSED,
1861 const char *name ATTRIBUTE_UNUSED,
1862 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1863 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1865 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1866 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name,
1867 size, DECL_ALIGN (decl));
1868 return true;
1869 #elif defined ASM_OUTPUT_ALIGNED_LOCAL
1870 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, DECL_ALIGN (decl));
1871 return true;
1872 #else
1873 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1874 return false;
1875 #endif
1878 /* A noswitch_section_callback for bss_noswitch_section. */
1880 #if defined ASM_OUTPUT_ALIGNED_BSS
1881 static bool
1882 emit_bss (tree decl ATTRIBUTE_UNUSED,
1883 const char *name ATTRIBUTE_UNUSED,
1884 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1885 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1887 #if defined ASM_OUTPUT_ALIGNED_BSS
1888 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size,
1889 get_variable_align (decl));
1890 return true;
1891 #endif
1893 #endif
1895 /* A noswitch_section_callback for comm_section. */
1897 static bool
1898 emit_common (tree decl ATTRIBUTE_UNUSED,
1899 const char *name ATTRIBUTE_UNUSED,
1900 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1901 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1903 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1904 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name,
1905 size, get_variable_align (decl));
1906 return true;
1907 #elif defined ASM_OUTPUT_ALIGNED_COMMON
1908 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size,
1909 get_variable_align (decl));
1910 return true;
1911 #else
1912 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
1913 return false;
1914 #endif
1917 /* A noswitch_section_callback for tls_comm_section. */
1919 static bool
1920 emit_tls_common (tree decl ATTRIBUTE_UNUSED,
1921 const char *name ATTRIBUTE_UNUSED,
1922 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1923 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1925 #ifdef ASM_OUTPUT_TLS_COMMON
1926 ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size);
1927 return true;
1928 #else
1929 sorry ("thread-local COMMON data not implemented");
1930 return true;
1931 #endif
1934 /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT.
1935 NAME is the name of DECL's SYMBOL_REF. */
1937 static void
1938 assemble_noswitch_variable (tree decl, const char *name, section *sect,
1939 unsigned int align)
1941 unsigned HOST_WIDE_INT size, rounded;
1943 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
1944 rounded = size;
1946 if ((flag_sanitize & SANITIZE_ADDRESS) && asan_protect_global (decl))
1947 size += asan_red_zone_size (size);
1949 /* Don't allocate zero bytes of common,
1950 since that means "undefined external" in the linker. */
1951 if (size == 0)
1952 rounded = 1;
1954 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1955 so that each uninitialized object starts on such a boundary. */
1956 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
1957 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1958 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1960 if (!sect->noswitch.callback (decl, name, size, rounded)
1961 && (unsigned HOST_WIDE_INT) (align / BITS_PER_UNIT) > rounded)
1962 error ("requested alignment for %q+D is greater than "
1963 "implemented alignment of %wu", decl, rounded);
1966 /* A subroutine of assemble_variable. Output the label and contents of
1967 DECL, whose address is a SYMBOL_REF with name NAME. DONT_OUTPUT_DATA
1968 is as for assemble_variable. */
1970 static void
1971 assemble_variable_contents (tree decl, const char *name,
1972 bool dont_output_data)
1974 /* Do any machine/system dependent processing of the object. */
1975 #ifdef ASM_DECLARE_OBJECT_NAME
1976 last_assemble_variable_decl = decl;
1977 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
1978 #else
1979 /* Standard thing is just output label for the object. */
1980 ASM_OUTPUT_LABEL (asm_out_file, name);
1981 #endif /* ASM_DECLARE_OBJECT_NAME */
1983 if (!dont_output_data)
1985 /* Caller is supposed to use varpool_get_constructor when it wants
1986 to output the body. */
1987 gcc_assert (!in_lto_p || DECL_INITIAL (decl) != error_mark_node);
1988 if (DECL_INITIAL (decl)
1989 && DECL_INITIAL (decl) != error_mark_node
1990 && !initializer_zerop (DECL_INITIAL (decl)))
1991 /* Output the actual data. */
1992 output_constant (DECL_INITIAL (decl),
1993 tree_to_uhwi (DECL_SIZE_UNIT (decl)),
1994 get_variable_align (decl));
1995 else
1996 /* Leave space for it. */
1997 assemble_zeros (tree_to_uhwi (DECL_SIZE_UNIT (decl)));
2001 /* Assemble everything that is needed for a variable or function declaration.
2002 Not used for automatic variables, and not used for function definitions.
2003 Should not be called for variables of incomplete structure type.
2005 TOP_LEVEL is nonzero if this variable has file scope.
2006 AT_END is nonzero if this is the special handling, at end of compilation,
2007 to define things that have had only tentative definitions.
2008 DONT_OUTPUT_DATA if nonzero means don't actually output the
2009 initial value (that will be done by the caller). */
2011 void
2012 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
2013 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
2015 const char *name;
2016 rtx decl_rtl, symbol;
2017 section *sect;
2018 unsigned int align;
2019 bool asan_protected = false;
2021 /* This function is supposed to handle VARIABLES. Ensure we have one. */
2022 gcc_assert (TREE_CODE (decl) == VAR_DECL);
2024 /* Emulated TLS had better not get this far. */
2025 gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl));
2027 last_assemble_variable_decl = 0;
2029 /* Normally no need to say anything here for external references,
2030 since assemble_external is called by the language-specific code
2031 when a declaration is first seen. */
2033 if (DECL_EXTERNAL (decl))
2034 return;
2036 /* Do nothing for global register variables. */
2037 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
2039 TREE_ASM_WRITTEN (decl) = 1;
2040 return;
2043 /* If type was incomplete when the variable was declared,
2044 see if it is complete now. */
2046 if (DECL_SIZE (decl) == 0)
2047 layout_decl (decl, 0);
2049 /* Still incomplete => don't allocate it; treat the tentative defn
2050 (which is what it must have been) as an `extern' reference. */
2052 if (!dont_output_data && DECL_SIZE (decl) == 0)
2054 error ("storage size of %q+D isn%'t known", decl);
2055 TREE_ASM_WRITTEN (decl) = 1;
2056 return;
2059 /* The first declaration of a variable that comes through this function
2060 decides whether it is global (in C, has external linkage)
2061 or local (in C, has internal linkage). So do nothing more
2062 if this function has already run. */
2064 if (TREE_ASM_WRITTEN (decl))
2065 return;
2067 /* Make sure targetm.encode_section_info is invoked before we set
2068 ASM_WRITTEN. */
2069 decl_rtl = DECL_RTL (decl);
2071 TREE_ASM_WRITTEN (decl) = 1;
2073 /* Do no output if -fsyntax-only. */
2074 if (flag_syntax_only)
2075 return;
2077 if (! dont_output_data
2078 && ! valid_constant_size_p (DECL_SIZE_UNIT (decl)))
2080 error ("size of variable %q+D is too large", decl);
2081 return;
2084 gcc_assert (MEM_P (decl_rtl));
2085 gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF);
2086 symbol = XEXP (decl_rtl, 0);
2088 /* If this symbol belongs to the tree constant pool, output the constant
2089 if it hasn't already been written. */
2090 if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
2092 tree decl = SYMBOL_REF_DECL (symbol);
2093 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
2094 output_constant_def_contents (symbol);
2095 return;
2098 app_disable ();
2100 name = XSTR (symbol, 0);
2101 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
2102 notice_global_symbol (decl);
2104 /* Compute the alignment of this data. */
2106 align_variable (decl, dont_output_data);
2108 if ((flag_sanitize & SANITIZE_ADDRESS)
2109 && asan_protect_global (decl))
2111 asan_protected = true;
2112 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
2113 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
2116 set_mem_align (decl_rtl, DECL_ALIGN (decl));
2118 align = get_variable_align (decl);
2120 if (TREE_PUBLIC (decl))
2121 maybe_assemble_visibility (decl);
2123 if (DECL_PRESERVE_P (decl))
2124 targetm.asm_out.mark_decl_preserved (name);
2126 /* First make the assembler name(s) global if appropriate. */
2127 sect = get_variable_section (decl, false);
2128 if (TREE_PUBLIC (decl)
2129 && (sect->common.flags & SECTION_COMMON) == 0)
2130 globalize_decl (decl);
2132 /* Output any data that we will need to use the address of. */
2133 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
2134 output_addressed_constants (DECL_INITIAL (decl));
2136 /* dbxout.c needs to know this. */
2137 if (sect && (sect->common.flags & SECTION_CODE) != 0)
2138 DECL_IN_TEXT_SECTION (decl) = 1;
2140 /* If the decl is part of an object_block, make sure that the decl
2141 has been positioned within its block, but do not write out its
2142 definition yet. output_object_blocks will do that later. */
2143 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
2145 gcc_assert (!dont_output_data);
2146 place_block_symbol (symbol);
2148 else if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
2149 assemble_noswitch_variable (decl, name, sect, align);
2150 else
2152 /* The following bit of code ensures that vtable_map
2153 variables are not only in the comdat section, but that
2154 each variable has its own unique comdat name. If this
2155 code is removed, the variables end up in the same section
2156 with a single comdat name.
2158 FIXME: resolve_unique_section needs to deal better with
2159 decls with both DECL_SECTION_NAME and DECL_ONE_ONLY. Once
2160 that is fixed, this if-else statement can be replaced with
2161 a single call to "switch_to_section (sect)". */
2162 if (sect->named.name
2163 && (strcmp (sect->named.name, ".vtable_map_vars") == 0))
2165 #if defined (OBJECT_FORMAT_ELF)
2166 targetm.asm_out.named_section (sect->named.name,
2167 sect->named.common.flags
2168 | SECTION_LINKONCE,
2169 DECL_NAME (decl));
2170 in_section = sect;
2171 #else
2172 switch_to_section (sect);
2173 #endif
2175 else
2176 switch_to_section (sect);
2177 if (align > BITS_PER_UNIT)
2178 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2179 assemble_variable_contents (decl, name, dont_output_data);
2180 if (asan_protected)
2182 unsigned HOST_WIDE_INT int size
2183 = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2184 assemble_zeros (asan_red_zone_size (size));
2190 /* Given a function declaration (FN_DECL), this function assembles the
2191 function into the .preinit_array section. */
2193 void
2194 assemble_vtv_preinit_initializer (tree fn_decl)
2196 section *sect;
2197 unsigned flags = SECTION_WRITE;
2198 rtx symbol = XEXP (DECL_RTL (fn_decl), 0);
2200 flags |= SECTION_NOTYPE;
2201 sect = get_section (".preinit_array", flags, fn_decl);
2202 switch_to_section (sect);
2203 assemble_addr_to_section (symbol, sect);
2206 /* Return 1 if type TYPE contains any pointers. */
2208 static int
2209 contains_pointers_p (tree type)
2211 switch (TREE_CODE (type))
2213 case POINTER_TYPE:
2214 case REFERENCE_TYPE:
2215 /* I'm not sure whether OFFSET_TYPE needs this treatment,
2216 so I'll play safe and return 1. */
2217 case OFFSET_TYPE:
2218 return 1;
2220 case RECORD_TYPE:
2221 case UNION_TYPE:
2222 case QUAL_UNION_TYPE:
2224 tree fields;
2225 /* For a type that has fields, see if the fields have pointers. */
2226 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2227 if (TREE_CODE (fields) == FIELD_DECL
2228 && contains_pointers_p (TREE_TYPE (fields)))
2229 return 1;
2230 return 0;
2233 case ARRAY_TYPE:
2234 /* An array type contains pointers if its element type does. */
2235 return contains_pointers_p (TREE_TYPE (type));
2237 default:
2238 return 0;
2242 /* We delay assemble_external processing until
2243 the compilation unit is finalized. This is the best we can do for
2244 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2245 it all the way to final. See PR 17982 for further discussion. */
2246 static GTY(()) tree pending_assemble_externals;
2248 #ifdef ASM_OUTPUT_EXTERNAL
2249 /* Some targets delay some output to final using TARGET_ASM_FILE_END.
2250 As a result, assemble_external can be called after the list of externals
2251 is processed and the pointer set destroyed. */
2252 static bool pending_assemble_externals_processed;
2254 /* Avoid O(external_decls**2) lookups in the pending_assemble_externals
2255 TREE_LIST in assemble_external. */
2256 static hash_set<tree> *pending_assemble_externals_set;
2258 /* True if DECL is a function decl for which no out-of-line copy exists.
2259 It is assumed that DECL's assembler name has been set. */
2261 static bool
2262 incorporeal_function_p (tree decl)
2264 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
2266 const char *name;
2268 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2269 && (DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA
2270 || DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA_WITH_ALIGN))
2271 return true;
2273 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2274 /* Atomic or sync builtins which have survived this far will be
2275 resolved externally and therefore are not incorporeal. */
2276 if (strncmp (name, "__builtin_", 10) == 0)
2277 return true;
2279 return false;
2282 /* Actually do the tests to determine if this is necessary, and invoke
2283 ASM_OUTPUT_EXTERNAL. */
2284 static void
2285 assemble_external_real (tree decl)
2287 rtx rtl = DECL_RTL (decl);
2289 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2290 && !SYMBOL_REF_USED (XEXP (rtl, 0))
2291 && !incorporeal_function_p (decl))
2293 /* Some systems do require some output. */
2294 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2295 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2298 #endif
2300 void
2301 process_pending_assemble_externals (void)
2303 #ifdef ASM_OUTPUT_EXTERNAL
2304 tree list;
2305 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2306 assemble_external_real (TREE_VALUE (list));
2308 pending_assemble_externals = 0;
2309 pending_assemble_externals_processed = true;
2310 delete pending_assemble_externals_set;
2311 #endif
2314 /* This TREE_LIST contains any weak symbol declarations waiting
2315 to be emitted. */
2316 static GTY(()) tree weak_decls;
2318 /* Output something to declare an external symbol to the assembler,
2319 and qualifiers such as weakness. (Most assemblers don't need
2320 extern declaration, so we normally output nothing.) Do nothing if
2321 DECL is not external. */
2323 void
2324 assemble_external (tree decl ATTRIBUTE_UNUSED)
2326 /* Make sure that the ASM_OUT_FILE is open.
2327 If it's not, we should not be calling this function. */
2328 gcc_assert (asm_out_file);
2330 /* In a perfect world, the following condition would be true.
2331 Sadly, the Java and Go front ends emit assembly *from the front end*,
2332 bypassing the call graph. See PR52739. Fix before GCC 4.8. */
2333 #if 0
2334 /* This function should only be called if we are expanding, or have
2335 expanded, to RTL.
2336 Ideally, only final.c would be calling this function, but it is
2337 not clear whether that would break things somehow. See PR 17982
2338 for further discussion. */
2339 gcc_assert (state == EXPANSION
2340 || state == FINISHED);
2341 #endif
2343 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2344 return;
2346 /* We want to output annotation for weak and external symbols at
2347 very last to check if they are references or not. */
2349 if (TARGET_SUPPORTS_WEAK
2350 && DECL_WEAK (decl)
2351 /* TREE_STATIC is a weird and abused creature which is not
2352 generally the right test for whether an entity has been
2353 locally emitted, inlined or otherwise not-really-extern, but
2354 for declarations that can be weak, it happens to be
2355 match. */
2356 && !TREE_STATIC (decl)
2357 && lookup_attribute ("weak", DECL_ATTRIBUTES (decl))
2358 && value_member (decl, weak_decls) == NULL_TREE)
2359 weak_decls = tree_cons (NULL, decl, weak_decls);
2361 #ifdef ASM_OUTPUT_EXTERNAL
2362 if (pending_assemble_externals_processed)
2364 assemble_external_real (decl);
2365 return;
2368 if (! pending_assemble_externals_set->add (decl))
2369 pending_assemble_externals = tree_cons (NULL, decl,
2370 pending_assemble_externals);
2371 #endif
2374 /* Similar, for calling a library function FUN. */
2376 void
2377 assemble_external_libcall (rtx fun)
2379 /* Declare library function name external when first used, if nec. */
2380 if (! SYMBOL_REF_USED (fun))
2382 SYMBOL_REF_USED (fun) = 1;
2383 targetm.asm_out.external_libcall (fun);
2387 /* Assemble a label named NAME. */
2389 void
2390 assemble_label (FILE *file, const char *name)
2392 ASM_OUTPUT_LABEL (file, name);
2395 /* Set the symbol_referenced flag for ID. */
2396 void
2397 mark_referenced (tree id)
2399 TREE_SYMBOL_REFERENCED (id) = 1;
2402 /* Set the symbol_referenced flag for DECL and notify callgraph. */
2403 void
2404 mark_decl_referenced (tree decl)
2406 if (TREE_CODE (decl) == FUNCTION_DECL)
2408 /* Extern inline functions don't become needed when referenced.
2409 If we know a method will be emitted in other TU and no new
2410 functions can be marked reachable, just use the external
2411 definition. */
2412 struct cgraph_node *node = cgraph_node::get_create (decl);
2413 if (!DECL_EXTERNAL (decl)
2414 && !node->definition)
2415 node->mark_force_output ();
2417 else if (TREE_CODE (decl) == VAR_DECL)
2419 varpool_node *node = varpool_node::get_create (decl);
2420 /* C++ frontend use mark_decl_references to force COMDAT variables
2421 to be output that might appear dead otherwise. */
2422 node->force_output = true;
2424 /* else do nothing - we can get various sorts of CST nodes here,
2425 which do not need to be marked. */
2429 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS
2430 until we find an identifier that is not itself a transparent alias.
2431 Modify the alias passed to it by reference (and all aliases on the
2432 way to the ultimate target), such that they do not have to be
2433 followed again, and return the ultimate target of the alias
2434 chain. */
2436 static inline tree
2437 ultimate_transparent_alias_target (tree *alias)
2439 tree target = *alias;
2441 if (IDENTIFIER_TRANSPARENT_ALIAS (target))
2443 gcc_assert (TREE_CHAIN (target));
2444 target = ultimate_transparent_alias_target (&TREE_CHAIN (target));
2445 gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target)
2446 && ! TREE_CHAIN (target));
2447 *alias = target;
2450 return target;
2453 /* Output to FILE (an assembly file) a reference to NAME. If NAME
2454 starts with a *, the rest of NAME is output verbatim. Otherwise
2455 NAME is transformed in a target-specific way (usually by the
2456 addition of an underscore). */
2458 void
2459 assemble_name_raw (FILE *file, const char *name)
2461 if (name[0] == '*')
2462 fputs (&name[1], file);
2463 else
2464 ASM_OUTPUT_LABELREF (file, name);
2467 /* Like assemble_name_raw, but should be used when NAME might refer to
2468 an entity that is also represented as a tree (like a function or
2469 variable). If NAME does refer to such an entity, that entity will
2470 be marked as referenced. */
2472 void
2473 assemble_name (FILE *file, const char *name)
2475 const char *real_name;
2476 tree id;
2478 real_name = targetm.strip_name_encoding (name);
2480 id = maybe_get_identifier (real_name);
2481 if (id)
2483 tree id_orig = id;
2485 mark_referenced (id);
2486 ultimate_transparent_alias_target (&id);
2487 if (id != id_orig)
2488 name = IDENTIFIER_POINTER (id);
2489 gcc_assert (! TREE_CHAIN (id));
2492 assemble_name_raw (file, name);
2495 /* Allocate SIZE bytes writable static space with a gensym name
2496 and return an RTX to refer to its address. */
2499 assemble_static_space (unsigned HOST_WIDE_INT size)
2501 char name[12];
2502 const char *namestring;
2503 rtx x;
2505 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2506 ++const_labelno;
2507 namestring = ggc_strdup (name);
2509 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2510 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2512 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2513 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2514 BIGGEST_ALIGNMENT);
2515 #else
2516 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2517 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2518 #else
2520 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2521 so that each uninitialized object starts on such a boundary. */
2522 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2523 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2524 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2525 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2526 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2527 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2529 #endif
2530 #endif
2531 return x;
2534 /* Assemble the static constant template for function entry trampolines.
2535 This is done at most once per compilation.
2536 Returns an RTX for the address of the template. */
2538 static GTY(()) rtx initial_trampoline;
2541 assemble_trampoline_template (void)
2543 char label[256];
2544 const char *name;
2545 int align;
2546 rtx symbol;
2548 gcc_assert (targetm.asm_out.trampoline_template != NULL);
2550 if (initial_trampoline)
2551 return initial_trampoline;
2553 /* By default, put trampoline templates in read-only data section. */
2555 #ifdef TRAMPOLINE_SECTION
2556 switch_to_section (TRAMPOLINE_SECTION);
2557 #else
2558 switch_to_section (readonly_data_section);
2559 #endif
2561 /* Write the assembler code to define one. */
2562 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2563 if (align > 0)
2564 ASM_OUTPUT_ALIGN (asm_out_file, align);
2566 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2567 targetm.asm_out.trampoline_template (asm_out_file);
2569 /* Record the rtl to refer to it. */
2570 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2571 name = ggc_strdup (label);
2572 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2573 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2575 initial_trampoline = gen_const_mem (BLKmode, symbol);
2576 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2577 set_mem_size (initial_trampoline, TRAMPOLINE_SIZE);
2579 return initial_trampoline;
2582 /* A and B are either alignments or offsets. Return the minimum alignment
2583 that may be assumed after adding the two together. */
2585 static inline unsigned
2586 min_align (unsigned int a, unsigned int b)
2588 return (a | b) & -(a | b);
2591 /* Return the assembler directive for creating a given kind of integer
2592 object. SIZE is the number of bytes in the object and ALIGNED_P
2593 indicates whether it is known to be aligned. Return NULL if the
2594 assembly dialect has no such directive.
2596 The returned string should be printed at the start of a new line and
2597 be followed immediately by the object's initial value. */
2599 const char *
2600 integer_asm_op (int size, int aligned_p)
2602 struct asm_int_op *ops;
2604 if (aligned_p)
2605 ops = &targetm.asm_out.aligned_op;
2606 else
2607 ops = &targetm.asm_out.unaligned_op;
2609 switch (size)
2611 case 1:
2612 return targetm.asm_out.byte_op;
2613 case 2:
2614 return ops->hi;
2615 case 4:
2616 return ops->si;
2617 case 8:
2618 return ops->di;
2619 case 16:
2620 return ops->ti;
2621 default:
2622 return NULL;
2626 /* Use directive OP to assemble an integer object X. Print OP at the
2627 start of the line, followed immediately by the value of X. */
2629 void
2630 assemble_integer_with_op (const char *op, rtx x)
2632 fputs (op, asm_out_file);
2633 output_addr_const (asm_out_file, x);
2634 fputc ('\n', asm_out_file);
2637 /* The default implementation of the asm_out.integer target hook. */
2639 bool
2640 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2641 unsigned int size ATTRIBUTE_UNUSED,
2642 int aligned_p ATTRIBUTE_UNUSED)
2644 const char *op = integer_asm_op (size, aligned_p);
2645 /* Avoid GAS bugs for large values. Specifically negative values whose
2646 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2647 if (size > UNITS_PER_WORD && size > POINTER_SIZE / BITS_PER_UNIT)
2648 return false;
2649 return op && (assemble_integer_with_op (op, x), true);
2652 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2653 the alignment of the integer in bits. Return 1 if we were able to output
2654 the constant, otherwise 0. We must be able to output the constant,
2655 if FORCE is nonzero. */
2657 bool
2658 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2660 int aligned_p;
2662 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2664 /* See if the target hook can handle this kind of object. */
2665 if (targetm.asm_out.integer (x, size, aligned_p))
2666 return true;
2668 /* If the object is a multi-byte one, try splitting it up. Split
2669 it into words it if is multi-word, otherwise split it into bytes. */
2670 if (size > 1)
2672 enum machine_mode omode, imode;
2673 unsigned int subalign;
2674 unsigned int subsize, i;
2675 enum mode_class mclass;
2677 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2678 subalign = MIN (align, subsize * BITS_PER_UNIT);
2679 if (GET_CODE (x) == CONST_FIXED)
2680 mclass = GET_MODE_CLASS (GET_MODE (x));
2681 else
2682 mclass = MODE_INT;
2684 omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0);
2685 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0);
2687 for (i = 0; i < size; i += subsize)
2689 rtx partial = simplify_subreg (omode, x, imode, i);
2690 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2691 break;
2693 if (i == size)
2694 return true;
2696 /* If we've printed some of it, but not all of it, there's no going
2697 back now. */
2698 gcc_assert (!i);
2701 gcc_assert (!force);
2703 return false;
2706 void
2707 assemble_real (REAL_VALUE_TYPE d, enum machine_mode mode, unsigned int align)
2709 long data[4] = {0, 0, 0, 0};
2710 int i;
2711 int bitsize, nelts, nunits, units_per;
2713 /* This is hairy. We have a quantity of known size. real_to_target
2714 will put it into an array of *host* longs, 32 bits per element
2715 (even if long is more than 32 bits). We need to determine the
2716 number of array elements that are occupied (nelts) and the number
2717 of *target* min-addressable units that will be occupied in the
2718 object file (nunits). We cannot assume that 32 divides the
2719 mode's bitsize (size * BITS_PER_UNIT) evenly.
2721 size * BITS_PER_UNIT is used here to make sure that padding bits
2722 (which might appear at either end of the value; real_to_target
2723 will include the padding bits in its output array) are included. */
2725 nunits = GET_MODE_SIZE (mode);
2726 bitsize = nunits * BITS_PER_UNIT;
2727 nelts = CEIL (bitsize, 32);
2728 units_per = 32 / BITS_PER_UNIT;
2730 real_to_target (data, &d, mode);
2732 /* Put out the first word with the specified alignment. */
2733 assemble_integer (GEN_INT (data[0]), MIN (nunits, units_per), align, 1);
2734 nunits -= units_per;
2736 /* Subsequent words need only 32-bit alignment. */
2737 align = min_align (align, 32);
2739 for (i = 1; i < nelts; i++)
2741 assemble_integer (GEN_INT (data[i]), MIN (nunits, units_per), align, 1);
2742 nunits -= units_per;
2746 /* Given an expression EXP with a constant value,
2747 reduce it to the sum of an assembler symbol and an integer.
2748 Store them both in the structure *VALUE.
2749 EXP must be reducible. */
2751 struct addr_const {
2752 rtx base;
2753 HOST_WIDE_INT offset;
2756 static void
2757 decode_addr_const (tree exp, struct addr_const *value)
2759 tree target = TREE_OPERAND (exp, 0);
2760 int offset = 0;
2761 rtx x;
2763 while (1)
2765 if (TREE_CODE (target) == COMPONENT_REF
2766 && tree_fits_shwi_p (byte_position (TREE_OPERAND (target, 1))))
2768 offset += int_byte_position (TREE_OPERAND (target, 1));
2769 target = TREE_OPERAND (target, 0);
2771 else if (TREE_CODE (target) == ARRAY_REF
2772 || TREE_CODE (target) == ARRAY_RANGE_REF)
2774 offset += (tree_to_uhwi (TYPE_SIZE_UNIT (TREE_TYPE (target)))
2775 * tree_to_shwi (TREE_OPERAND (target, 1)));
2776 target = TREE_OPERAND (target, 0);
2778 else if (TREE_CODE (target) == MEM_REF
2779 && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR)
2781 offset += mem_ref_offset (target).to_short_addr ();
2782 target = TREE_OPERAND (TREE_OPERAND (target, 0), 0);
2784 else if (TREE_CODE (target) == INDIRECT_REF
2785 && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR
2786 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0))
2787 == ADDR_EXPR)
2788 target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0);
2789 else
2790 break;
2793 switch (TREE_CODE (target))
2795 case VAR_DECL:
2796 case FUNCTION_DECL:
2797 x = DECL_RTL (target);
2798 break;
2800 case LABEL_DECL:
2801 x = gen_rtx_MEM (FUNCTION_MODE,
2802 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2803 break;
2805 case REAL_CST:
2806 case FIXED_CST:
2807 case STRING_CST:
2808 case COMPLEX_CST:
2809 case CONSTRUCTOR:
2810 case INTEGER_CST:
2811 x = output_constant_def (target, 1);
2812 break;
2814 default:
2815 gcc_unreachable ();
2818 gcc_assert (MEM_P (x));
2819 x = XEXP (x, 0);
2821 value->base = x;
2822 value->offset = offset;
2826 static GTY((param_is (struct constant_descriptor_tree)))
2827 htab_t const_desc_htab;
2829 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2831 /* Constant pool accessor function. */
2833 htab_t
2834 constant_pool_htab (void)
2836 return const_desc_htab;
2839 /* Compute a hash code for a constant expression. */
2841 static hashval_t
2842 const_desc_hash (const void *ptr)
2844 return ((const struct constant_descriptor_tree *)ptr)->hash;
2847 static hashval_t
2848 const_hash_1 (const tree exp)
2850 const char *p;
2851 hashval_t hi;
2852 int len, i;
2853 enum tree_code code = TREE_CODE (exp);
2855 /* Either set P and LEN to the address and len of something to hash and
2856 exit the switch or return a value. */
2858 switch (code)
2860 case INTEGER_CST:
2861 p = (char *) &TREE_INT_CST_ELT (exp, 0);
2862 len = TREE_INT_CST_NUNITS (exp) * sizeof (HOST_WIDE_INT);
2863 break;
2865 case REAL_CST:
2866 return real_hash (TREE_REAL_CST_PTR (exp));
2868 case FIXED_CST:
2869 return fixed_hash (TREE_FIXED_CST_PTR (exp));
2871 case STRING_CST:
2872 p = TREE_STRING_POINTER (exp);
2873 len = TREE_STRING_LENGTH (exp);
2874 break;
2876 case COMPLEX_CST:
2877 return (const_hash_1 (TREE_REALPART (exp)) * 5
2878 + const_hash_1 (TREE_IMAGPART (exp)));
2880 case VECTOR_CST:
2882 unsigned i;
2884 hi = 7 + VECTOR_CST_NELTS (exp);
2886 for (i = 0; i < VECTOR_CST_NELTS (exp); ++i)
2887 hi = hi * 563 + const_hash_1 (VECTOR_CST_ELT (exp, i));
2889 return hi;
2892 case CONSTRUCTOR:
2894 unsigned HOST_WIDE_INT idx;
2895 tree value;
2897 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2899 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
2900 if (value)
2901 hi = hi * 603 + const_hash_1 (value);
2903 return hi;
2906 case ADDR_EXPR:
2907 case FDESC_EXPR:
2909 struct addr_const value;
2911 decode_addr_const (exp, &value);
2912 switch (GET_CODE (value.base))
2914 case SYMBOL_REF:
2915 /* Don't hash the address of the SYMBOL_REF;
2916 only use the offset and the symbol name. */
2917 hi = value.offset;
2918 p = XSTR (value.base, 0);
2919 for (i = 0; p[i] != 0; i++)
2920 hi = ((hi * 613) + (unsigned) (p[i]));
2921 break;
2923 case LABEL_REF:
2924 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13;
2925 break;
2927 default:
2928 gcc_unreachable ();
2931 return hi;
2933 case PLUS_EXPR:
2934 case POINTER_PLUS_EXPR:
2935 case MINUS_EXPR:
2936 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2937 + const_hash_1 (TREE_OPERAND (exp, 1)));
2939 CASE_CONVERT:
2940 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
2942 default:
2943 /* A language specific constant. Just hash the code. */
2944 return code;
2947 /* Compute hashing function. */
2948 hi = len;
2949 for (i = 0; i < len; i++)
2950 hi = ((hi * 613) + (unsigned) (p[i]));
2952 return hi;
2955 /* Wrapper of compare_constant, for the htab interface. */
2956 static int
2957 const_desc_eq (const void *p1, const void *p2)
2959 const struct constant_descriptor_tree *const c1
2960 = (const struct constant_descriptor_tree *) p1;
2961 const struct constant_descriptor_tree *const c2
2962 = (const struct constant_descriptor_tree *) p2;
2963 if (c1->hash != c2->hash)
2964 return 0;
2965 return compare_constant (c1->value, c2->value);
2968 /* Compare t1 and t2, and return 1 only if they are known to result in
2969 the same bit pattern on output. */
2971 static int
2972 compare_constant (const tree t1, const tree t2)
2974 enum tree_code typecode;
2976 if (t1 == NULL_TREE)
2977 return t2 == NULL_TREE;
2978 if (t2 == NULL_TREE)
2979 return 0;
2981 if (TREE_CODE (t1) != TREE_CODE (t2))
2982 return 0;
2984 switch (TREE_CODE (t1))
2986 case INTEGER_CST:
2987 /* Integer constants are the same only if the same width of type. */
2988 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2989 return 0;
2990 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2991 return 0;
2992 return tree_int_cst_equal (t1, t2);
2994 case REAL_CST:
2995 /* Real constants are the same only if the same width of type. */
2996 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2997 return 0;
2999 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
3001 case FIXED_CST:
3002 /* Fixed constants are the same only if the same width of type. */
3003 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3004 return 0;
3006 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
3008 case STRING_CST:
3009 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3010 return 0;
3012 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
3013 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
3014 TREE_STRING_LENGTH (t1)));
3016 case COMPLEX_CST:
3017 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
3018 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
3020 case VECTOR_CST:
3022 unsigned i;
3024 if (VECTOR_CST_NELTS (t1) != VECTOR_CST_NELTS (t2))
3025 return 0;
3027 for (i = 0; i < VECTOR_CST_NELTS (t1); ++i)
3028 if (!compare_constant (VECTOR_CST_ELT (t1, i),
3029 VECTOR_CST_ELT (t2, i)))
3030 return 0;
3032 return 1;
3035 case CONSTRUCTOR:
3037 vec<constructor_elt, va_gc> *v1, *v2;
3038 unsigned HOST_WIDE_INT idx;
3040 typecode = TREE_CODE (TREE_TYPE (t1));
3041 if (typecode != TREE_CODE (TREE_TYPE (t2)))
3042 return 0;
3044 if (typecode == ARRAY_TYPE)
3046 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
3047 /* For arrays, check that the sizes all match. */
3048 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
3049 || size_1 == -1
3050 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
3051 return 0;
3053 else
3055 /* For record and union constructors, require exact type
3056 equality. */
3057 if (TREE_TYPE (t1) != TREE_TYPE (t2))
3058 return 0;
3061 v1 = CONSTRUCTOR_ELTS (t1);
3062 v2 = CONSTRUCTOR_ELTS (t2);
3063 if (vec_safe_length (v1) != vec_safe_length (v2))
3064 return 0;
3066 for (idx = 0; idx < vec_safe_length (v1); ++idx)
3068 constructor_elt *c1 = &(*v1)[idx];
3069 constructor_elt *c2 = &(*v2)[idx];
3071 /* Check that each value is the same... */
3072 if (!compare_constant (c1->value, c2->value))
3073 return 0;
3074 /* ... and that they apply to the same fields! */
3075 if (typecode == ARRAY_TYPE)
3077 if (!compare_constant (c1->index, c2->index))
3078 return 0;
3080 else
3082 if (c1->index != c2->index)
3083 return 0;
3087 return 1;
3090 case ADDR_EXPR:
3091 case FDESC_EXPR:
3093 struct addr_const value1, value2;
3094 enum rtx_code code;
3095 int ret;
3097 decode_addr_const (t1, &value1);
3098 decode_addr_const (t2, &value2);
3100 if (value1.offset != value2.offset)
3101 return 0;
3103 code = GET_CODE (value1.base);
3104 if (code != GET_CODE (value2.base))
3105 return 0;
3107 switch (code)
3109 case SYMBOL_REF:
3110 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3111 break;
3113 case LABEL_REF:
3114 ret = (CODE_LABEL_NUMBER (XEXP (value1.base, 0))
3115 == CODE_LABEL_NUMBER (XEXP (value2.base, 0)));
3116 break;
3118 default:
3119 gcc_unreachable ();
3121 return ret;
3124 case PLUS_EXPR:
3125 case POINTER_PLUS_EXPR:
3126 case MINUS_EXPR:
3127 case RANGE_EXPR:
3128 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3129 && compare_constant (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3131 CASE_CONVERT:
3132 case VIEW_CONVERT_EXPR:
3133 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3135 default:
3136 return 0;
3139 gcc_unreachable ();
3142 /* Return the section into which constant EXP should be placed. */
3144 static section *
3145 get_constant_section (tree exp, unsigned int align)
3147 return targetm.asm_out.select_section (exp,
3148 compute_reloc_for_constant (exp),
3149 align);
3152 /* Return the size of constant EXP in bytes. */
3154 static HOST_WIDE_INT
3155 get_constant_size (tree exp)
3157 HOST_WIDE_INT size;
3159 size = int_size_in_bytes (TREE_TYPE (exp));
3160 if (TREE_CODE (exp) == STRING_CST)
3161 size = MAX (TREE_STRING_LENGTH (exp), size);
3162 return size;
3165 /* Subroutine of output_constant_def:
3166 No constant equal to EXP is known to have been output.
3167 Make a constant descriptor to enter EXP in the hash table.
3168 Assign the label number and construct RTL to refer to the
3169 constant's location in memory.
3170 Caller is responsible for updating the hash table. */
3172 static struct constant_descriptor_tree *
3173 build_constant_desc (tree exp)
3175 struct constant_descriptor_tree *desc;
3176 rtx symbol, rtl;
3177 char label[256];
3178 int labelno;
3179 tree decl;
3181 desc = ggc_alloc<constant_descriptor_tree> ();
3182 desc->value = exp;
3184 /* Create a string containing the label name, in LABEL. */
3185 labelno = const_labelno++;
3186 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3188 /* Construct the VAR_DECL associated with the constant. */
3189 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3190 TREE_TYPE (exp));
3191 DECL_ARTIFICIAL (decl) = 1;
3192 DECL_IGNORED_P (decl) = 1;
3193 TREE_READONLY (decl) = 1;
3194 TREE_STATIC (decl) = 1;
3195 TREE_ADDRESSABLE (decl) = 1;
3196 /* We don't set the RTL yet as this would cause varpool to assume that the
3197 variable is referenced. Moreover, it would just be dropped in LTO mode.
3198 Instead we set the flag that will be recognized in make_decl_rtl. */
3199 DECL_IN_CONSTANT_POOL (decl) = 1;
3200 DECL_INITIAL (decl) = desc->value;
3201 /* ??? CONSTANT_ALIGNMENT hasn't been updated for vector types on most
3202 architectures so use DATA_ALIGNMENT as well, except for strings. */
3203 if (TREE_CODE (exp) == STRING_CST)
3205 #ifdef CONSTANT_ALIGNMENT
3206 DECL_ALIGN (decl) = CONSTANT_ALIGNMENT (exp, DECL_ALIGN (decl));
3207 #endif
3209 else
3210 align_variable (decl, 0);
3212 /* Now construct the SYMBOL_REF and the MEM. */
3213 if (use_object_blocks_p ())
3215 section *sect = get_constant_section (exp, DECL_ALIGN (decl));
3216 symbol = create_block_symbol (ggc_strdup (label),
3217 get_block_for_section (sect), -1);
3219 else
3220 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3221 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3222 SET_SYMBOL_REF_DECL (symbol, decl);
3223 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3225 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3226 set_mem_attributes (rtl, exp, 1);
3227 set_mem_alias_set (rtl, 0);
3228 set_mem_alias_set (rtl, const_alias_set);
3230 /* We cannot share RTX'es in pool entries.
3231 Mark this piece of RTL as required for unsharing. */
3232 RTX_FLAG (rtl, used) = 1;
3234 /* Set flags or add text to the name to record information, such as
3235 that it is a local symbol. If the name is changed, the macro
3236 ASM_OUTPUT_LABELREF will have to know how to strip this
3237 information. This call might invalidate our local variable
3238 SYMBOL; we can't use it afterward. */
3239 targetm.encode_section_info (exp, rtl, true);
3241 desc->rtl = rtl;
3243 return desc;
3246 /* Return an rtx representing a reference to constant data in memory
3247 for the constant expression EXP.
3249 If assembler code for such a constant has already been output,
3250 return an rtx to refer to it.
3251 Otherwise, output such a constant in memory
3252 and generate an rtx for it.
3254 If DEFER is nonzero, this constant can be deferred and output only
3255 if referenced in the function after all optimizations.
3257 `const_desc_table' records which constants already have label strings. */
3260 output_constant_def (tree exp, int defer)
3262 struct constant_descriptor_tree *desc;
3263 struct constant_descriptor_tree key;
3264 void **loc;
3266 /* Look up EXP in the table of constant descriptors. If we didn't find
3267 it, create a new one. */
3268 key.value = exp;
3269 key.hash = const_hash_1 (exp);
3270 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3272 desc = (struct constant_descriptor_tree *) *loc;
3273 if (desc == 0)
3275 desc = build_constant_desc (exp);
3276 desc->hash = key.hash;
3277 *loc = desc;
3280 maybe_output_constant_def_contents (desc, defer);
3281 return desc->rtl;
3284 /* Subroutine of output_constant_def: Decide whether or not we need to
3285 output the constant DESC now, and if so, do it. */
3286 static void
3287 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3288 int defer)
3290 rtx symbol = XEXP (desc->rtl, 0);
3291 tree exp = desc->value;
3293 if (flag_syntax_only)
3294 return;
3296 if (TREE_ASM_WRITTEN (exp))
3297 /* Already output; don't do it again. */
3298 return;
3300 /* We can always defer constants as long as the context allows
3301 doing so. */
3302 if (defer)
3304 /* Increment n_deferred_constants if it exists. It needs to be at
3305 least as large as the number of constants actually referred to
3306 by the function. If it's too small we'll stop looking too early
3307 and fail to emit constants; if it's too large we'll only look
3308 through the entire function when we could have stopped earlier. */
3309 if (cfun)
3310 n_deferred_constants++;
3311 return;
3314 output_constant_def_contents (symbol);
3317 /* Subroutine of output_constant_def_contents. Output the definition
3318 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3319 constant's alignment in bits. */
3321 static void
3322 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3324 HOST_WIDE_INT size;
3326 size = get_constant_size (exp);
3328 /* Do any machine/system dependent processing of the constant. */
3329 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3331 /* Output the value of EXP. */
3332 output_constant (exp, size, align);
3335 /* We must output the constant data referred to by SYMBOL; do so. */
3337 static void
3338 output_constant_def_contents (rtx symbol)
3340 tree decl = SYMBOL_REF_DECL (symbol);
3341 tree exp = DECL_INITIAL (decl);
3342 unsigned int align;
3343 bool asan_protected = false;
3345 /* Make sure any other constants whose addresses appear in EXP
3346 are assigned label numbers. */
3347 output_addressed_constants (exp);
3349 /* We are no longer deferring this constant. */
3350 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3352 if ((flag_sanitize & SANITIZE_ADDRESS)
3353 && TREE_CODE (exp) == STRING_CST
3354 && asan_protect_global (exp))
3356 asan_protected = true;
3357 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
3358 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
3361 /* If the constant is part of an object block, make sure that the
3362 decl has been positioned within its block, but do not write out
3363 its definition yet. output_object_blocks will do that later. */
3364 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3365 place_block_symbol (symbol);
3366 else
3368 align = DECL_ALIGN (decl);
3369 switch_to_section (get_constant_section (exp, align));
3370 if (align > BITS_PER_UNIT)
3371 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3372 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3373 if (asan_protected)
3375 HOST_WIDE_INT size = get_constant_size (exp);
3376 assemble_zeros (asan_red_zone_size (size));
3381 /* Look up EXP in the table of constant descriptors. Return the rtl
3382 if it has been emitted, else null. */
3385 lookup_constant_def (tree exp)
3387 struct constant_descriptor_tree *desc;
3388 struct constant_descriptor_tree key;
3390 key.value = exp;
3391 key.hash = const_hash_1 (exp);
3392 desc = (struct constant_descriptor_tree *)
3393 htab_find_with_hash (const_desc_htab, &key, key.hash);
3395 return (desc ? desc->rtl : NULL_RTX);
3398 /* Return a tree representing a reference to constant data in memory
3399 for the constant expression EXP.
3401 This is the counterpart of output_constant_def at the Tree level. */
3403 tree
3404 tree_output_constant_def (tree exp)
3406 struct constant_descriptor_tree *desc, key;
3407 void **loc;
3408 tree decl;
3410 /* Look up EXP in the table of constant descriptors. If we didn't find
3411 it, create a new one. */
3412 key.value = exp;
3413 key.hash = const_hash_1 (exp);
3414 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3416 desc = (struct constant_descriptor_tree *) *loc;
3417 if (desc == 0)
3419 desc = build_constant_desc (exp);
3420 desc->hash = key.hash;
3421 *loc = desc;
3424 decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3425 varpool_node::finalize_decl (decl);
3426 return decl;
3429 /* Used in the hash tables to avoid outputting the same constant
3430 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3431 are output once per function, not once per file. */
3432 /* ??? Only a few targets need per-function constant pools. Most
3433 can use one per-file pool. Should add a targetm bit to tell the
3434 difference. */
3436 struct GTY(()) rtx_constant_pool {
3437 /* Pointers to first and last constant in pool, as ordered by offset. */
3438 struct constant_descriptor_rtx *first;
3439 struct constant_descriptor_rtx *last;
3441 /* Hash facility for making memory-constants from constant rtl-expressions.
3442 It is used on RISC machines where immediate integer arguments and
3443 constant addresses are restricted so that such constants must be stored
3444 in memory. */
3445 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_htab;
3447 /* Current offset in constant pool (does not include any
3448 machine-specific header). */
3449 HOST_WIDE_INT offset;
3452 struct GTY((chain_next ("%h.next"))) constant_descriptor_rtx {
3453 struct constant_descriptor_rtx *next;
3454 rtx mem;
3455 rtx sym;
3456 rtx constant;
3457 HOST_WIDE_INT offset;
3458 hashval_t hash;
3459 enum machine_mode mode;
3460 unsigned int align;
3461 int labelno;
3462 int mark;
3465 /* Hash and compare functions for const_rtx_htab. */
3467 static hashval_t
3468 const_desc_rtx_hash (const void *ptr)
3470 const struct constant_descriptor_rtx *const desc
3471 = (const struct constant_descriptor_rtx *) ptr;
3472 return desc->hash;
3475 static int
3476 const_desc_rtx_eq (const void *a, const void *b)
3478 const struct constant_descriptor_rtx *const x
3479 = (const struct constant_descriptor_rtx *) a;
3480 const struct constant_descriptor_rtx *const y
3481 = (const struct constant_descriptor_rtx *) b;
3483 if (x->mode != y->mode)
3484 return 0;
3485 return rtx_equal_p (x->constant, y->constant);
3488 /* This is the worker function for const_rtx_hash, called via for_each_rtx. */
3490 static int
3491 const_rtx_hash_1 (rtx *xp, void *data)
3493 unsigned HOST_WIDE_INT hwi;
3494 enum machine_mode mode;
3495 enum rtx_code code;
3496 hashval_t h, *hp;
3497 rtx x;
3498 int i;
3500 x = *xp;
3501 code = GET_CODE (x);
3502 mode = GET_MODE (x);
3503 h = (hashval_t) code * 1048573 + mode;
3505 switch (code)
3507 case CONST_INT:
3508 hwi = INTVAL (x);
3510 fold_hwi:
3512 int shift = sizeof (hashval_t) * CHAR_BIT;
3513 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3515 h ^= (hashval_t) hwi;
3516 for (i = 1; i < n; ++i)
3518 hwi >>= shift;
3519 h ^= (hashval_t) hwi;
3522 break;
3524 case CONST_WIDE_INT:
3525 hwi = GET_MODE_PRECISION (mode);
3527 for (i = 0; i < CONST_WIDE_INT_NUNITS (x); i++)
3528 hwi ^= CONST_WIDE_INT_ELT (x, i);
3529 goto fold_hwi;
3532 case CONST_DOUBLE:
3533 if (TARGET_SUPPORTS_WIDE_INT == 0 && mode == VOIDmode)
3535 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3536 goto fold_hwi;
3538 else
3539 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3540 break;
3542 case CONST_FIXED:
3543 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3544 break;
3546 case CONST_VECTOR:
3548 int i;
3549 for (i = XVECLEN (x, 0); i-- > 0; )
3550 h = h * 251 + const_rtx_hash_1 (&XVECEXP (x, 0, i), data);
3552 break;
3554 case SYMBOL_REF:
3555 h ^= htab_hash_string (XSTR (x, 0));
3556 break;
3558 case LABEL_REF:
3559 h = h * 251 + CODE_LABEL_NUMBER (XEXP (x, 0));
3560 break;
3562 case UNSPEC:
3563 case UNSPEC_VOLATILE:
3564 h = h * 251 + XINT (x, 1);
3565 break;
3567 default:
3568 break;
3571 hp = (hashval_t *) data;
3572 *hp = *hp * 509 + h;
3573 return 0;
3576 /* Compute a hash value for X, which should be a constant. */
3578 static hashval_t
3579 const_rtx_hash (rtx x)
3581 hashval_t h = 0;
3582 for_each_rtx (&x, const_rtx_hash_1, &h);
3583 return h;
3587 /* Create and return a new rtx constant pool. */
3589 static struct rtx_constant_pool *
3590 create_constant_pool (void)
3592 struct rtx_constant_pool *pool;
3594 pool = ggc_alloc<rtx_constant_pool> ();
3595 pool->const_rtx_htab = htab_create_ggc (31, const_desc_rtx_hash,
3596 const_desc_rtx_eq, NULL);
3597 pool->first = NULL;
3598 pool->last = NULL;
3599 pool->offset = 0;
3600 return pool;
3603 /* Initialize constant pool hashing for a new function. */
3605 void
3606 init_varasm_status (void)
3608 crtl->varasm.pool = create_constant_pool ();
3609 crtl->varasm.deferred_constants = 0;
3612 /* Given a MINUS expression, simplify it if both sides
3613 include the same symbol. */
3616 simplify_subtraction (rtx x)
3618 rtx r = simplify_rtx (x);
3619 return r ? r : x;
3622 /* Given a constant rtx X, make (or find) a memory constant for its value
3623 and return a MEM rtx to refer to it in memory. */
3626 force_const_mem (enum machine_mode mode, rtx x)
3628 struct constant_descriptor_rtx *desc, tmp;
3629 struct rtx_constant_pool *pool;
3630 char label[256];
3631 rtx def, symbol;
3632 hashval_t hash;
3633 unsigned int align;
3634 void **slot;
3636 /* If we're not allowed to drop X into the constant pool, don't. */
3637 if (targetm.cannot_force_const_mem (mode, x))
3638 return NULL_RTX;
3640 /* Record that this function has used a constant pool entry. */
3641 crtl->uses_const_pool = 1;
3643 /* Decide which pool to use. */
3644 pool = (targetm.use_blocks_for_constant_p (mode, x)
3645 ? shared_constant_pool
3646 : crtl->varasm.pool);
3648 /* Lookup the value in the hashtable. */
3649 tmp.constant = x;
3650 tmp.mode = mode;
3651 hash = const_rtx_hash (x);
3652 slot = htab_find_slot_with_hash (pool->const_rtx_htab, &tmp, hash, INSERT);
3653 desc = (struct constant_descriptor_rtx *) *slot;
3655 /* If the constant was already present, return its memory. */
3656 if (desc)
3657 return copy_rtx (desc->mem);
3659 /* Otherwise, create a new descriptor. */
3660 desc = ggc_alloc<constant_descriptor_rtx> ();
3661 *slot = desc;
3663 /* Align the location counter as required by EXP's data type. */
3664 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3665 #ifdef CONSTANT_ALIGNMENT
3667 tree type = lang_hooks.types.type_for_mode (mode, 0);
3668 if (type != NULL_TREE)
3669 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3671 #endif
3673 pool->offset += (align / BITS_PER_UNIT) - 1;
3674 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3676 desc->next = NULL;
3677 desc->constant = copy_rtx (tmp.constant);
3678 desc->offset = pool->offset;
3679 desc->hash = hash;
3680 desc->mode = mode;
3681 desc->align = align;
3682 desc->labelno = const_labelno;
3683 desc->mark = 0;
3685 pool->offset += GET_MODE_SIZE (mode);
3686 if (pool->last)
3687 pool->last->next = desc;
3688 else
3689 pool->first = pool->last = desc;
3690 pool->last = desc;
3692 /* Create a string containing the label name, in LABEL. */
3693 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3694 ++const_labelno;
3696 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3697 the constants pool. */
3698 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3700 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3701 symbol = create_block_symbol (ggc_strdup (label),
3702 get_block_for_section (sect), -1);
3704 else
3705 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3706 desc->sym = symbol;
3707 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3708 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3709 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3711 /* Construct the MEM. */
3712 desc->mem = def = gen_const_mem (mode, symbol);
3713 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3714 set_mem_align (def, align);
3716 /* If we're dropping a label to the constant pool, make sure we
3717 don't delete it. */
3718 if (GET_CODE (x) == LABEL_REF)
3719 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3721 return copy_rtx (def);
3724 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3727 get_pool_constant (rtx addr)
3729 return SYMBOL_REF_CONSTANT (addr)->constant;
3732 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3733 and whether it has been output or not. */
3736 get_pool_constant_mark (rtx addr, bool *pmarked)
3738 struct constant_descriptor_rtx *desc;
3740 desc = SYMBOL_REF_CONSTANT (addr);
3741 *pmarked = (desc->mark != 0);
3742 return desc->constant;
3745 /* Similar, return the mode. */
3747 enum machine_mode
3748 get_pool_mode (const_rtx addr)
3750 return SYMBOL_REF_CONSTANT (addr)->mode;
3753 /* Return the size of the constant pool. */
3756 get_pool_size (void)
3758 return crtl->varasm.pool->offset;
3761 /* Worker function for output_constant_pool_1. Emit assembly for X
3762 in MODE with known alignment ALIGN. */
3764 static void
3765 output_constant_pool_2 (enum machine_mode mode, rtx x, unsigned int align)
3767 switch (GET_MODE_CLASS (mode))
3769 case MODE_FLOAT:
3770 case MODE_DECIMAL_FLOAT:
3772 REAL_VALUE_TYPE r;
3774 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3775 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3776 assemble_real (r, mode, align);
3777 break;
3780 case MODE_INT:
3781 case MODE_PARTIAL_INT:
3782 case MODE_FRACT:
3783 case MODE_UFRACT:
3784 case MODE_ACCUM:
3785 case MODE_UACCUM:
3786 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3787 break;
3789 case MODE_VECTOR_FLOAT:
3790 case MODE_VECTOR_INT:
3791 case MODE_VECTOR_FRACT:
3792 case MODE_VECTOR_UFRACT:
3793 case MODE_VECTOR_ACCUM:
3794 case MODE_VECTOR_UACCUM:
3796 int i, units;
3797 enum machine_mode submode = GET_MODE_INNER (mode);
3798 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3800 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3801 units = CONST_VECTOR_NUNITS (x);
3803 for (i = 0; i < units; i++)
3805 rtx elt = CONST_VECTOR_ELT (x, i);
3806 output_constant_pool_2 (submode, elt, i ? subalign : align);
3809 break;
3811 default:
3812 gcc_unreachable ();
3816 /* Worker function for output_constant_pool. Emit constant DESC,
3817 giving it ALIGN bits of alignment. */
3819 static void
3820 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3821 unsigned int align)
3823 rtx x, tmp;
3825 x = desc->constant;
3827 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3828 whose CODE_LABEL has been deleted. This can occur if a jump table
3829 is eliminated by optimization. If so, write a constant of zero
3830 instead. Note that this can also happen by turning the
3831 CODE_LABEL into a NOTE. */
3832 /* ??? This seems completely and utterly wrong. Certainly it's
3833 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3834 functioning even with INSN_DELETED_P and friends. */
3836 tmp = x;
3837 switch (GET_CODE (tmp))
3839 case CONST:
3840 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3841 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
3842 break;
3843 tmp = XEXP (XEXP (tmp, 0), 0);
3844 /* FALLTHRU */
3846 case LABEL_REF:
3847 tmp = XEXP (tmp, 0);
3848 gcc_assert (!INSN_DELETED_P (tmp));
3849 gcc_assert (!NOTE_P (tmp)
3850 || NOTE_KIND (tmp) != NOTE_INSN_DELETED);
3851 break;
3853 default:
3854 break;
3857 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3858 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3859 align, desc->labelno, done);
3860 #endif
3862 assemble_align (align);
3864 /* Output the label. */
3865 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3867 /* Output the data. */
3868 output_constant_pool_2 (desc->mode, x, align);
3870 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3871 sections have proper size. */
3872 if (align > GET_MODE_BITSIZE (desc->mode)
3873 && in_section
3874 && (in_section->common.flags & SECTION_MERGE))
3875 assemble_align (align);
3877 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3878 done:
3879 #endif
3880 return;
3883 /* Given a SYMBOL_REF CURRENT_RTX, mark it and all constants it refers
3884 to as used. Emit referenced deferred strings. This function can
3885 be used with for_each_rtx to mark all SYMBOL_REFs in an rtx. */
3887 static int
3888 mark_constant (rtx *current_rtx, void *data ATTRIBUTE_UNUSED)
3890 rtx x = *current_rtx;
3892 if (x == NULL_RTX || GET_CODE (x) != SYMBOL_REF)
3893 return 0;
3895 if (CONSTANT_POOL_ADDRESS_P (x))
3897 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
3898 if (desc->mark == 0)
3900 desc->mark = 1;
3901 for_each_rtx (&desc->constant, mark_constant, NULL);
3904 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3906 tree decl = SYMBOL_REF_DECL (x);
3907 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
3909 n_deferred_constants--;
3910 output_constant_def_contents (x);
3914 return -1;
3917 /* Look through appropriate parts of INSN, marking all entries in the
3918 constant pool which are actually being used. Entries that are only
3919 referenced by other constants are also marked as used. Emit
3920 deferred strings that are used. */
3922 static void
3923 mark_constants (rtx_insn *insn)
3925 if (!INSN_P (insn))
3926 return;
3928 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3929 insns, not any notes that may be attached. We don't want to mark
3930 a constant just because it happens to appear in a REG_EQUIV note. */
3931 if (rtx_sequence *seq = dyn_cast <rtx_sequence *> (PATTERN (insn)))
3933 int i, n = seq->len ();
3934 for (i = 0; i < n; ++i)
3936 rtx subinsn = seq->element (i);
3937 if (INSN_P (subinsn))
3938 for_each_rtx (&PATTERN (subinsn), mark_constant, NULL);
3941 else
3942 for_each_rtx (&PATTERN (insn), mark_constant, NULL);
3945 /* Look through the instructions for this function, and mark all the
3946 entries in POOL which are actually being used. Emit deferred constants
3947 which have indeed been used. */
3949 static void
3950 mark_constant_pool (void)
3952 rtx_insn *insn;
3954 if (!crtl->uses_const_pool && n_deferred_constants == 0)
3955 return;
3957 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3958 mark_constants (insn);
3961 /* Write all the constants in POOL. */
3963 static void
3964 output_constant_pool_contents (struct rtx_constant_pool *pool)
3966 struct constant_descriptor_rtx *desc;
3968 for (desc = pool->first; desc ; desc = desc->next)
3969 if (desc->mark)
3971 /* If the constant is part of an object_block, make sure that
3972 the constant has been positioned within its block, but do not
3973 write out its definition yet. output_object_blocks will do
3974 that later. */
3975 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
3976 && SYMBOL_REF_BLOCK (desc->sym))
3977 place_block_symbol (desc->sym);
3978 else
3980 switch_to_section (targetm.asm_out.select_rtx_section
3981 (desc->mode, desc->constant, desc->align));
3982 output_constant_pool_1 (desc, desc->align);
3987 /* Mark all constants that are used in the current function, then write
3988 out the function's private constant pool. */
3990 static void
3991 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
3992 tree fndecl ATTRIBUTE_UNUSED)
3994 struct rtx_constant_pool *pool = crtl->varasm.pool;
3996 /* It is possible for gcc to call force_const_mem and then to later
3997 discard the instructions which refer to the constant. In such a
3998 case we do not need to output the constant. */
3999 mark_constant_pool ();
4001 #ifdef ASM_OUTPUT_POOL_PROLOGUE
4002 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
4003 #endif
4005 output_constant_pool_contents (pool);
4007 #ifdef ASM_OUTPUT_POOL_EPILOGUE
4008 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
4009 #endif
4012 /* Write the contents of the shared constant pool. */
4014 void
4015 output_shared_constant_pool (void)
4017 output_constant_pool_contents (shared_constant_pool);
4020 /* Determine what kind of relocations EXP may need. */
4023 compute_reloc_for_constant (tree exp)
4025 int reloc = 0, reloc2;
4026 tree tem;
4028 switch (TREE_CODE (exp))
4030 case ADDR_EXPR:
4031 case FDESC_EXPR:
4032 /* Go inside any operations that get_inner_reference can handle and see
4033 if what's inside is a constant: no need to do anything here for
4034 addresses of variables or functions. */
4035 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4036 tem = TREE_OPERAND (tem, 0))
4039 if (TREE_CODE (tem) == MEM_REF
4040 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4042 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4043 break;
4046 if (!targetm.binds_local_p (tem))
4047 reloc |= 2;
4048 else
4049 reloc |= 1;
4050 break;
4052 case PLUS_EXPR:
4053 case POINTER_PLUS_EXPR:
4054 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4055 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4056 break;
4058 case MINUS_EXPR:
4059 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4060 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4061 /* The difference of two local labels is computable at link time. */
4062 if (reloc == 1 && reloc2 == 1)
4063 reloc = 0;
4064 else
4065 reloc |= reloc2;
4066 break;
4068 CASE_CONVERT:
4069 case VIEW_CONVERT_EXPR:
4070 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4071 break;
4073 case CONSTRUCTOR:
4075 unsigned HOST_WIDE_INT idx;
4076 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4077 if (tem != 0)
4078 reloc |= compute_reloc_for_constant (tem);
4080 break;
4082 default:
4083 break;
4085 return reloc;
4088 /* Find all the constants whose addresses are referenced inside of EXP,
4089 and make sure assembler code with a label has been output for each one.
4090 Indicate whether an ADDR_EXPR has been encountered. */
4092 static void
4093 output_addressed_constants (tree exp)
4095 tree tem;
4097 switch (TREE_CODE (exp))
4099 case ADDR_EXPR:
4100 case FDESC_EXPR:
4101 /* Go inside any operations that get_inner_reference can handle and see
4102 if what's inside is a constant: no need to do anything here for
4103 addresses of variables or functions. */
4104 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4105 tem = TREE_OPERAND (tem, 0))
4108 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4109 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4110 tem = DECL_INITIAL (tem);
4112 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4113 output_constant_def (tem, 0);
4115 if (TREE_CODE (tem) == MEM_REF)
4116 output_addressed_constants (TREE_OPERAND (tem, 0));
4117 break;
4119 case PLUS_EXPR:
4120 case POINTER_PLUS_EXPR:
4121 case MINUS_EXPR:
4122 output_addressed_constants (TREE_OPERAND (exp, 1));
4123 /* Fall through. */
4125 CASE_CONVERT:
4126 case VIEW_CONVERT_EXPR:
4127 output_addressed_constants (TREE_OPERAND (exp, 0));
4128 break;
4130 case CONSTRUCTOR:
4132 unsigned HOST_WIDE_INT idx;
4133 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4134 if (tem != 0)
4135 output_addressed_constants (tem);
4137 break;
4139 default:
4140 break;
4144 /* Whether a constructor CTOR is a valid static constant initializer if all
4145 its elements are. This used to be internal to initializer_constant_valid_p
4146 and has been exposed to let other functions like categorize_ctor_elements
4147 evaluate the property while walking a constructor for other purposes. */
4149 bool
4150 constructor_static_from_elts_p (const_tree ctor)
4152 return (TREE_CONSTANT (ctor)
4153 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4154 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4155 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4158 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4159 tree *cache);
4161 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4162 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4163 which are valid when ENDTYPE is an integer of any size; in
4164 particular, this does not accept a pointer minus a constant. This
4165 returns null_pointer_node if the VALUE is an absolute constant
4166 which can be used to initialize a static variable. Otherwise it
4167 returns NULL. */
4169 static tree
4170 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4172 tree op0, op1;
4174 if (!INTEGRAL_TYPE_P (endtype))
4175 return NULL_TREE;
4177 op0 = TREE_OPERAND (value, 0);
4178 op1 = TREE_OPERAND (value, 1);
4180 /* Like STRIP_NOPS except allow the operand mode to widen. This
4181 works around a feature of fold that simplifies (int)(p1 - p2) to
4182 ((int)p1 - (int)p2) under the theory that the narrower operation
4183 is cheaper. */
4185 while (CONVERT_EXPR_P (op0)
4186 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4188 tree inner = TREE_OPERAND (op0, 0);
4189 if (inner == error_mark_node
4190 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4191 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
4192 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4193 break;
4194 op0 = inner;
4197 while (CONVERT_EXPR_P (op1)
4198 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4200 tree inner = TREE_OPERAND (op1, 0);
4201 if (inner == error_mark_node
4202 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4203 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
4204 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4205 break;
4206 op1 = inner;
4209 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4210 if (!op0)
4211 return NULL_TREE;
4213 op1 = initializer_constant_valid_p_1 (op1, endtype,
4214 cache ? cache + 2 : NULL);
4215 /* Both initializers must be known. */
4216 if (op1)
4218 if (op0 == op1
4219 && (op0 == null_pointer_node
4220 || TREE_CODE (value) == MINUS_EXPR))
4221 return null_pointer_node;
4223 /* Support differences between labels. */
4224 if (TREE_CODE (op0) == LABEL_DECL
4225 && TREE_CODE (op1) == LABEL_DECL)
4226 return null_pointer_node;
4228 if (TREE_CODE (op0) == STRING_CST
4229 && TREE_CODE (op1) == STRING_CST
4230 && operand_equal_p (op0, op1, 1))
4231 return null_pointer_node;
4234 return NULL_TREE;
4237 /* Helper function of initializer_constant_valid_p.
4238 Return nonzero if VALUE is a valid constant-valued expression
4239 for use in initializing a static variable; one that can be an
4240 element of a "constant" initializer.
4242 Return null_pointer_node if the value is absolute;
4243 if it is relocatable, return the variable that determines the relocation.
4244 We assume that VALUE has been folded as much as possible;
4245 therefore, we do not need to check for such things as
4246 arithmetic-combinations of integers.
4248 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4250 static tree
4251 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4253 tree ret;
4255 switch (TREE_CODE (value))
4257 case CONSTRUCTOR:
4258 if (constructor_static_from_elts_p (value))
4260 unsigned HOST_WIDE_INT idx;
4261 tree elt;
4262 bool absolute = true;
4264 if (cache && cache[0] == value)
4265 return cache[1];
4266 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4268 tree reloc;
4269 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4270 NULL);
4271 if (!reloc)
4273 if (cache)
4275 cache[0] = value;
4276 cache[1] = NULL_TREE;
4278 return NULL_TREE;
4280 if (reloc != null_pointer_node)
4281 absolute = false;
4283 /* For a non-absolute relocation, there is no single
4284 variable that can be "the variable that determines the
4285 relocation." */
4286 if (cache)
4288 cache[0] = value;
4289 cache[1] = absolute ? null_pointer_node : error_mark_node;
4291 return absolute ? null_pointer_node : error_mark_node;
4294 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4296 case INTEGER_CST:
4297 case VECTOR_CST:
4298 case REAL_CST:
4299 case FIXED_CST:
4300 case STRING_CST:
4301 case COMPLEX_CST:
4302 return null_pointer_node;
4304 case ADDR_EXPR:
4305 case FDESC_EXPR:
4307 tree op0 = staticp (TREE_OPERAND (value, 0));
4308 if (op0)
4310 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4311 to be a constant, this is old-skool offsetof-like nonsense. */
4312 if (TREE_CODE (op0) == INDIRECT_REF
4313 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4314 return null_pointer_node;
4315 /* Taking the address of a nested function involves a trampoline,
4316 unless we don't need or want one. */
4317 if (TREE_CODE (op0) == FUNCTION_DECL
4318 && DECL_STATIC_CHAIN (op0)
4319 && !TREE_NO_TRAMPOLINE (value))
4320 return NULL_TREE;
4321 /* "&{...}" requires a temporary to hold the constructed
4322 object. */
4323 if (TREE_CODE (op0) == CONSTRUCTOR)
4324 return NULL_TREE;
4326 return op0;
4329 case NON_LVALUE_EXPR:
4330 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4331 endtype, cache);
4333 case VIEW_CONVERT_EXPR:
4335 tree src = TREE_OPERAND (value, 0);
4336 tree src_type = TREE_TYPE (src);
4337 tree dest_type = TREE_TYPE (value);
4339 /* Allow view-conversions from aggregate to non-aggregate type only
4340 if the bit pattern is fully preserved afterwards; otherwise, the
4341 RTL expander won't be able to apply a subsequent transformation
4342 to the underlying constructor. */
4343 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4345 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4346 return initializer_constant_valid_p_1 (src, endtype, cache);
4347 else
4348 return NULL_TREE;
4351 /* Allow all other kinds of view-conversion. */
4352 return initializer_constant_valid_p_1 (src, endtype, cache);
4355 CASE_CONVERT:
4357 tree src = TREE_OPERAND (value, 0);
4358 tree src_type = TREE_TYPE (src);
4359 tree dest_type = TREE_TYPE (value);
4361 /* Allow conversions between pointer types, floating-point
4362 types, and offset types. */
4363 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4364 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4365 || (TREE_CODE (dest_type) == OFFSET_TYPE
4366 && TREE_CODE (src_type) == OFFSET_TYPE))
4367 return initializer_constant_valid_p_1 (src, endtype, cache);
4369 /* Allow length-preserving conversions between integer types. */
4370 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4371 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4372 return initializer_constant_valid_p_1 (src, endtype, cache);
4374 /* Allow conversions between other integer types only if
4375 explicit value. */
4376 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type))
4378 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4379 if (inner == null_pointer_node)
4380 return null_pointer_node;
4381 break;
4384 /* Allow (int) &foo provided int is as wide as a pointer. */
4385 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4386 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4387 return initializer_constant_valid_p_1 (src, endtype, cache);
4389 /* Likewise conversions from int to pointers, but also allow
4390 conversions from 0. */
4391 if ((POINTER_TYPE_P (dest_type)
4392 || TREE_CODE (dest_type) == OFFSET_TYPE)
4393 && INTEGRAL_TYPE_P (src_type))
4395 if (TREE_CODE (src) == INTEGER_CST
4396 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4397 return null_pointer_node;
4398 if (integer_zerop (src))
4399 return null_pointer_node;
4400 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4401 return initializer_constant_valid_p_1 (src, endtype, cache);
4404 /* Allow conversions to struct or union types if the value
4405 inside is okay. */
4406 if (TREE_CODE (dest_type) == RECORD_TYPE
4407 || TREE_CODE (dest_type) == UNION_TYPE)
4408 return initializer_constant_valid_p_1 (src, endtype, cache);
4410 break;
4412 case POINTER_PLUS_EXPR:
4413 case PLUS_EXPR:
4414 /* Any valid floating-point constants will have been folded by now;
4415 with -frounding-math we hit this with addition of two constants. */
4416 if (TREE_CODE (endtype) == REAL_TYPE)
4417 return NULL_TREE;
4418 if (cache && cache[0] == value)
4419 return cache[1];
4420 if (! INTEGRAL_TYPE_P (endtype)
4421 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4423 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4424 tree valid0
4425 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4426 endtype, ncache);
4427 tree valid1
4428 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4429 endtype, ncache + 2);
4430 /* If either term is absolute, use the other term's relocation. */
4431 if (valid0 == null_pointer_node)
4432 ret = valid1;
4433 else if (valid1 == null_pointer_node)
4434 ret = valid0;
4435 /* Support narrowing pointer differences. */
4436 else
4437 ret = narrowing_initializer_constant_valid_p (value, endtype,
4438 ncache);
4440 else
4441 /* Support narrowing pointer differences. */
4442 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4443 if (cache)
4445 cache[0] = value;
4446 cache[1] = ret;
4448 return ret;
4450 case MINUS_EXPR:
4451 if (TREE_CODE (endtype) == REAL_TYPE)
4452 return NULL_TREE;
4453 if (cache && cache[0] == value)
4454 return cache[1];
4455 if (! INTEGRAL_TYPE_P (endtype)
4456 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4458 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4459 tree valid0
4460 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4461 endtype, ncache);
4462 tree valid1
4463 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4464 endtype, ncache + 2);
4465 /* Win if second argument is absolute. */
4466 if (valid1 == null_pointer_node)
4467 ret = valid0;
4468 /* Win if both arguments have the same relocation.
4469 Then the value is absolute. */
4470 else if (valid0 == valid1 && valid0 != 0)
4471 ret = null_pointer_node;
4472 /* Since GCC guarantees that string constants are unique in the
4473 generated code, a subtraction between two copies of the same
4474 constant string is absolute. */
4475 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4476 && valid1 && TREE_CODE (valid1) == STRING_CST
4477 && operand_equal_p (valid0, valid1, 1))
4478 ret = null_pointer_node;
4479 /* Support narrowing differences. */
4480 else
4481 ret = narrowing_initializer_constant_valid_p (value, endtype,
4482 ncache);
4484 else
4485 /* Support narrowing differences. */
4486 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4487 if (cache)
4489 cache[0] = value;
4490 cache[1] = ret;
4492 return ret;
4494 default:
4495 break;
4498 return NULL_TREE;
4501 /* Return nonzero if VALUE is a valid constant-valued expression
4502 for use in initializing a static variable; one that can be an
4503 element of a "constant" initializer.
4505 Return null_pointer_node if the value is absolute;
4506 if it is relocatable, return the variable that determines the relocation.
4507 We assume that VALUE has been folded as much as possible;
4508 therefore, we do not need to check for such things as
4509 arithmetic-combinations of integers. */
4510 tree
4511 initializer_constant_valid_p (tree value, tree endtype)
4513 return initializer_constant_valid_p_1 (value, endtype, NULL);
4516 /* Return true if VALUE is a valid constant-valued expression
4517 for use in initializing a static bit-field; one that can be
4518 an element of a "constant" initializer. */
4520 bool
4521 initializer_constant_valid_for_bitfield_p (tree value)
4523 /* For bitfields we support integer constants or possibly nested aggregates
4524 of such. */
4525 switch (TREE_CODE (value))
4527 case CONSTRUCTOR:
4529 unsigned HOST_WIDE_INT idx;
4530 tree elt;
4532 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4533 if (!initializer_constant_valid_for_bitfield_p (elt))
4534 return false;
4535 return true;
4538 case INTEGER_CST:
4539 case REAL_CST:
4540 return true;
4542 case VIEW_CONVERT_EXPR:
4543 case NON_LVALUE_EXPR:
4544 return
4545 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4547 default:
4548 break;
4551 return false;
4554 /* output_constructor outer state of relevance in recursive calls, typically
4555 for nested aggregate bitfields. */
4557 typedef struct {
4558 unsigned int bit_offset; /* current position in ... */
4559 int byte; /* ... the outer byte buffer. */
4560 } oc_outer_state;
4562 static unsigned HOST_WIDE_INT
4563 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int,
4564 oc_outer_state *);
4566 /* Output assembler code for constant EXP, with no label.
4567 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4568 Assumes output_addressed_constants has been done on EXP already.
4570 Generate at least SIZE bytes of assembler data, padding at the end
4571 with zeros if necessary. SIZE must always be specified. The returned
4572 value is the actual number of bytes of assembler data generated, which
4573 may be bigger than SIZE if the object contains a variable length field.
4575 SIZE is important for structure constructors,
4576 since trailing members may have been omitted from the constructor.
4577 It is also important for initialization of arrays from string constants
4578 since the full length of the string constant might not be wanted.
4579 It is also needed for initialization of unions, where the initializer's
4580 type is just one member, and that may not be as long as the union.
4582 There a case in which we would fail to output exactly SIZE bytes:
4583 for a structure constructor that wants to produce more than SIZE bytes.
4584 But such constructors will never be generated for any possible input.
4586 ALIGN is the alignment of the data in bits. */
4588 static unsigned HOST_WIDE_INT
4589 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align)
4591 enum tree_code code;
4592 unsigned HOST_WIDE_INT thissize;
4594 if (size == 0 || flag_syntax_only)
4595 return size;
4597 /* See if we're trying to initialize a pointer in a non-default mode
4598 to the address of some declaration somewhere. If the target says
4599 the mode is valid for pointers, assume the target has a way of
4600 resolving it. */
4601 if (TREE_CODE (exp) == NOP_EXPR
4602 && POINTER_TYPE_P (TREE_TYPE (exp))
4603 && targetm.addr_space.valid_pointer_mode
4604 (TYPE_MODE (TREE_TYPE (exp)),
4605 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4607 tree saved_type = TREE_TYPE (exp);
4609 /* Peel off any intermediate conversions-to-pointer for valid
4610 pointer modes. */
4611 while (TREE_CODE (exp) == NOP_EXPR
4612 && POINTER_TYPE_P (TREE_TYPE (exp))
4613 && targetm.addr_space.valid_pointer_mode
4614 (TYPE_MODE (TREE_TYPE (exp)),
4615 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4616 exp = TREE_OPERAND (exp, 0);
4618 /* If what we're left with is the address of something, we can
4619 convert the address to the final type and output it that
4620 way. */
4621 if (TREE_CODE (exp) == ADDR_EXPR)
4622 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4623 /* Likewise for constant ints. */
4624 else if (TREE_CODE (exp) == INTEGER_CST)
4625 exp = wide_int_to_tree (saved_type, exp);
4629 /* Eliminate any conversions since we'll be outputting the underlying
4630 constant. */
4631 while (CONVERT_EXPR_P (exp)
4632 || TREE_CODE (exp) == NON_LVALUE_EXPR
4633 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4635 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4636 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4638 /* Make sure eliminating the conversion is really a no-op, except with
4639 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4640 union types to allow for Ada unchecked unions. */
4641 if (type_size > op_size
4642 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4643 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4644 /* Keep the conversion. */
4645 break;
4646 else
4647 exp = TREE_OPERAND (exp, 0);
4650 code = TREE_CODE (TREE_TYPE (exp));
4651 thissize = int_size_in_bytes (TREE_TYPE (exp));
4653 /* Allow a constructor with no elements for any data type.
4654 This means to fill the space with zeros. */
4655 if (TREE_CODE (exp) == CONSTRUCTOR
4656 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4658 assemble_zeros (size);
4659 return size;
4662 if (TREE_CODE (exp) == FDESC_EXPR)
4664 #ifdef ASM_OUTPUT_FDESC
4665 HOST_WIDE_INT part = tree_to_shwi (TREE_OPERAND (exp, 1));
4666 tree decl = TREE_OPERAND (exp, 0);
4667 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4668 #else
4669 gcc_unreachable ();
4670 #endif
4671 return size;
4674 /* Now output the underlying data. If we've handling the padding, return.
4675 Otherwise, break and ensure SIZE is the size written. */
4676 switch (code)
4678 case BOOLEAN_TYPE:
4679 case INTEGER_TYPE:
4680 case ENUMERAL_TYPE:
4681 case POINTER_TYPE:
4682 case REFERENCE_TYPE:
4683 case OFFSET_TYPE:
4684 case FIXED_POINT_TYPE:
4685 case NULLPTR_TYPE:
4686 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
4687 EXPAND_INITIALIZER),
4688 MIN (size, thissize), align, 0))
4689 error ("initializer for integer/fixed-point value is too complicated");
4690 break;
4692 case REAL_TYPE:
4693 if (TREE_CODE (exp) != REAL_CST)
4694 error ("initializer for floating value is not a floating constant");
4695 else
4696 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)), align);
4697 break;
4699 case COMPLEX_TYPE:
4700 output_constant (TREE_REALPART (exp), thissize / 2, align);
4701 output_constant (TREE_IMAGPART (exp), thissize / 2,
4702 min_align (align, BITS_PER_UNIT * (thissize / 2)));
4703 break;
4705 case ARRAY_TYPE:
4706 case VECTOR_TYPE:
4707 switch (TREE_CODE (exp))
4709 case CONSTRUCTOR:
4710 return output_constructor (exp, size, align, NULL);
4711 case STRING_CST:
4712 thissize
4713 = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4714 assemble_string (TREE_STRING_POINTER (exp), thissize);
4715 break;
4716 case VECTOR_CST:
4718 enum machine_mode inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4719 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4720 int elt_size = GET_MODE_SIZE (inner);
4721 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align);
4722 thissize = elt_size;
4723 for (unsigned int i = 1; i < VECTOR_CST_NELTS (exp); i++)
4725 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign);
4726 thissize += elt_size;
4728 break;
4730 default:
4731 gcc_unreachable ();
4733 break;
4735 case RECORD_TYPE:
4736 case UNION_TYPE:
4737 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4738 return output_constructor (exp, size, align, NULL);
4740 case ERROR_MARK:
4741 return 0;
4743 default:
4744 gcc_unreachable ();
4747 if (size > thissize)
4748 assemble_zeros (size - thissize);
4750 return size;
4754 /* Subroutine of output_constructor, used for computing the size of
4755 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4756 type with an unspecified upper bound. */
4758 static unsigned HOST_WIDE_INT
4759 array_size_for_constructor (tree val)
4761 tree max_index;
4762 unsigned HOST_WIDE_INT cnt;
4763 tree index, value, tmp;
4764 offset_int i;
4766 /* This code used to attempt to handle string constants that are not
4767 arrays of single-bytes, but nothing else does, so there's no point in
4768 doing it here. */
4769 if (TREE_CODE (val) == STRING_CST)
4770 return TREE_STRING_LENGTH (val);
4772 max_index = NULL_TREE;
4773 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
4775 if (TREE_CODE (index) == RANGE_EXPR)
4776 index = TREE_OPERAND (index, 1);
4777 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
4778 max_index = index;
4781 if (max_index == NULL_TREE)
4782 return 0;
4784 /* Compute the total number of array elements. */
4785 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
4786 i = wi::to_offset (max_index) - wi::to_offset (tmp) + 1;
4788 /* Multiply by the array element unit size to find number of bytes. */
4789 i *= wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
4791 gcc_assert (wi::fits_uhwi_p (i));
4792 return i.to_uhwi ();
4795 /* Other datastructures + helpers for output_constructor. */
4797 /* output_constructor local state to support interaction with helpers. */
4799 typedef struct {
4801 /* Received arguments. */
4802 tree exp; /* Constructor expression. */
4803 tree type; /* Type of constructor expression. */
4804 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */
4805 unsigned int align; /* Known initial alignment. */
4806 tree min_index; /* Lower bound if specified for an array. */
4808 /* Output processing state. */
4809 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */
4810 int byte; /* Part of a bitfield byte yet to be output. */
4811 int last_relative_index; /* Implicit or explicit index of the last
4812 array element output within a bitfield. */
4813 bool byte_buffer_in_use; /* Whether BYTE is in use. */
4815 /* Current element. */
4816 tree field; /* Current field decl in a record. */
4817 tree val; /* Current element value. */
4818 tree index; /* Current element index. */
4820 } oc_local_state;
4822 /* Helper for output_constructor. From the current LOCAL state, output a
4823 RANGE_EXPR element. */
4825 static void
4826 output_constructor_array_range (oc_local_state *local)
4828 unsigned HOST_WIDE_INT fieldsize
4829 = int_size_in_bytes (TREE_TYPE (local->type));
4831 HOST_WIDE_INT lo_index
4832 = tree_to_shwi (TREE_OPERAND (local->index, 0));
4833 HOST_WIDE_INT hi_index
4834 = tree_to_shwi (TREE_OPERAND (local->index, 1));
4835 HOST_WIDE_INT index;
4837 unsigned int align2
4838 = min_align (local->align, fieldsize * BITS_PER_UNIT);
4840 for (index = lo_index; index <= hi_index; index++)
4842 /* Output the element's initial value. */
4843 if (local->val == NULL_TREE)
4844 assemble_zeros (fieldsize);
4845 else
4846 fieldsize = output_constant (local->val, fieldsize, align2);
4848 /* Count its size. */
4849 local->total_bytes += fieldsize;
4853 /* Helper for output_constructor. From the current LOCAL state, output a
4854 field element that is not true bitfield or part of an outer one. */
4856 static void
4857 output_constructor_regular_field (oc_local_state *local)
4859 /* Field size and position. Since this structure is static, we know the
4860 positions are constant. */
4861 unsigned HOST_WIDE_INT fieldsize;
4862 HOST_WIDE_INT fieldpos;
4864 unsigned int align2;
4866 if (local->index != NULL_TREE)
4868 /* Perform the index calculation in modulo arithmetic but
4869 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
4870 but we are using an unsigned sizetype. */
4871 unsigned prec = TYPE_PRECISION (sizetype);
4872 offset_int idx = wi::sext (wi::to_offset (local->index)
4873 - wi::to_offset (local->min_index), prec);
4874 fieldpos = (idx * wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (local->val))))
4875 .to_short_addr ();
4877 else if (local->field != NULL_TREE)
4878 fieldpos = int_byte_position (local->field);
4879 else
4880 fieldpos = 0;
4882 /* Output any buffered-up bit-fields preceding this element. */
4883 if (local->byte_buffer_in_use)
4885 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4886 local->total_bytes++;
4887 local->byte_buffer_in_use = false;
4890 /* Advance to offset of this element.
4891 Note no alignment needed in an array, since that is guaranteed
4892 if each element has the proper size. */
4893 if ((local->field != NULL_TREE || local->index != NULL_TREE)
4894 && fieldpos > local->total_bytes)
4896 assemble_zeros (fieldpos - local->total_bytes);
4897 local->total_bytes = fieldpos;
4900 /* Find the alignment of this element. */
4901 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
4903 /* Determine size this element should occupy. */
4904 if (local->field)
4906 fieldsize = 0;
4908 /* If this is an array with an unspecified upper bound,
4909 the initializer determines the size. */
4910 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
4911 but we cannot do this until the deprecated support for
4912 initializing zero-length array members is removed. */
4913 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
4914 && TYPE_DOMAIN (TREE_TYPE (local->field))
4915 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field))))
4917 fieldsize = array_size_for_constructor (local->val);
4918 /* Given a non-empty initialization, this field had
4919 better be last. */
4920 gcc_assert (!fieldsize || !DECL_CHAIN (local->field));
4922 else
4923 fieldsize = tree_to_uhwi (DECL_SIZE_UNIT (local->field));
4925 else
4926 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
4928 /* Output the element's initial value. */
4929 if (local->val == NULL_TREE)
4930 assemble_zeros (fieldsize);
4931 else
4932 fieldsize = output_constant (local->val, fieldsize, align2);
4934 /* Count its size. */
4935 local->total_bytes += fieldsize;
4938 /* Helper for output_constructor. From the LOCAL state, output an element
4939 that is a true bitfield or part of an outer one. BIT_OFFSET is the offset
4940 from the start of a possibly ongoing outer byte buffer. */
4942 static void
4943 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
4945 /* Bit size of this element. */
4946 HOST_WIDE_INT ebitsize
4947 = (local->field
4948 ? tree_to_uhwi (DECL_SIZE (local->field))
4949 : tree_to_uhwi (TYPE_SIZE (TREE_TYPE (local->type))));
4951 /* Relative index of this element if this is an array component. */
4952 HOST_WIDE_INT relative_index
4953 = (!local->field
4954 ? (local->index
4955 ? (tree_to_shwi (local->index)
4956 - tree_to_shwi (local->min_index))
4957 : local->last_relative_index + 1)
4958 : 0);
4960 /* Bit position of this element from the start of the containing
4961 constructor. */
4962 HOST_WIDE_INT constructor_relative_ebitpos
4963 = (local->field
4964 ? int_bit_position (local->field)
4965 : ebitsize * relative_index);
4967 /* Bit position of this element from the start of a possibly ongoing
4968 outer byte buffer. */
4969 HOST_WIDE_INT byte_relative_ebitpos
4970 = bit_offset + constructor_relative_ebitpos;
4972 /* From the start of a possibly ongoing outer byte buffer, offsets to
4973 the first bit of this element and to the first bit past the end of
4974 this element. */
4975 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
4976 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
4978 local->last_relative_index = relative_index;
4980 if (local->val == NULL_TREE)
4981 local->val = integer_zero_node;
4983 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
4984 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
4985 local->val = TREE_OPERAND (local->val, 0);
4987 if (TREE_CODE (local->val) != INTEGER_CST
4988 && TREE_CODE (local->val) != CONSTRUCTOR)
4990 error ("invalid initial value for member %qE", DECL_NAME (local->field));
4991 return;
4994 /* If this field does not start in this (or next) byte, skip some bytes. */
4995 if (next_offset / BITS_PER_UNIT != local->total_bytes)
4997 /* Output remnant of any bit field in previous bytes. */
4998 if (local->byte_buffer_in_use)
5000 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5001 local->total_bytes++;
5002 local->byte_buffer_in_use = false;
5005 /* If still not at proper byte, advance to there. */
5006 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5008 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
5009 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
5010 local->total_bytes = next_offset / BITS_PER_UNIT;
5014 /* Set up the buffer if necessary. */
5015 if (!local->byte_buffer_in_use)
5017 local->byte = 0;
5018 if (ebitsize > 0)
5019 local->byte_buffer_in_use = true;
5022 /* If this is nested constructor, recurse passing the bit offset and the
5023 pending data, then retrieve the new pending data afterwards. */
5024 if (TREE_CODE (local->val) == CONSTRUCTOR)
5026 oc_outer_state temp_state;
5027 temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5028 temp_state.byte = local->byte;
5029 local->total_bytes
5030 += output_constructor (local->val, 0, 0, &temp_state);
5031 local->byte = temp_state.byte;
5032 return;
5035 /* Otherwise, we must split the element into pieces that fall within
5036 separate bytes, and combine each byte with previous or following
5037 bit-fields. */
5038 while (next_offset < end_offset)
5040 int this_time;
5041 int shift;
5042 HOST_WIDE_INT value;
5043 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5044 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5046 /* Advance from byte to byte within this element when necessary. */
5047 while (next_byte != local->total_bytes)
5049 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5050 local->total_bytes++;
5051 local->byte = 0;
5054 /* Number of bits we can process at once (all part of the same byte). */
5055 this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5056 if (BYTES_BIG_ENDIAN)
5058 /* On big-endian machine, take the most significant bits (of the
5059 bits that are significant) first and put them into bytes from
5060 the most significant end. */
5061 shift = end_offset - next_offset - this_time;
5063 /* Don't try to take a bunch of bits that cross
5064 the word boundary in the INTEGER_CST. We can
5065 only select bits from one element. */
5066 if ((shift / HOST_BITS_PER_WIDE_INT)
5067 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5069 const int end = shift + this_time - 1;
5070 shift = end & -HOST_BITS_PER_WIDE_INT;
5071 this_time = end - shift + 1;
5074 /* Now get the bits from the appropriate constant word. */
5075 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5076 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5078 /* Get the result. This works only when:
5079 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5080 local->byte |= (((value >> shift)
5081 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5082 << (BITS_PER_UNIT - this_time - next_bit));
5084 else
5086 /* On little-endian machines, take the least significant bits of
5087 the value first and pack them starting at the least significant
5088 bits of the bytes. */
5089 shift = next_offset - byte_relative_ebitpos;
5091 /* Don't try to take a bunch of bits that cross
5092 the word boundary in the INTEGER_CST. We can
5093 only select bits from one element. */
5094 if ((shift / HOST_BITS_PER_WIDE_INT)
5095 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5096 this_time
5097 = HOST_BITS_PER_WIDE_INT - (shift & (HOST_BITS_PER_WIDE_INT - 1));
5099 /* Now get the bits from the appropriate constant word. */
5100 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5101 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5103 /* Get the result. This works only when:
5104 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5105 local->byte |= (((value >> shift)
5106 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5107 << next_bit);
5110 next_offset += this_time;
5111 local->byte_buffer_in_use = true;
5115 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5116 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5117 caller output state of relevance in recursive invocations. */
5119 static unsigned HOST_WIDE_INT
5120 output_constructor (tree exp, unsigned HOST_WIDE_INT size,
5121 unsigned int align, oc_outer_state *outer)
5123 unsigned HOST_WIDE_INT cnt;
5124 constructor_elt *ce;
5126 oc_local_state local;
5128 /* Setup our local state to communicate with helpers. */
5129 local.exp = exp;
5130 local.type = TREE_TYPE (exp);
5131 local.size = size;
5132 local.align = align;
5133 if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5134 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5135 else
5136 local.min_index = NULL_TREE;
5138 local.total_bytes = 0;
5139 local.byte_buffer_in_use = outer != NULL;
5140 local.byte = outer ? outer->byte : 0;
5141 local.last_relative_index = -1;
5143 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5145 /* As CE goes through the elements of the constant, FIELD goes through the
5146 structure fields if the constant is a structure. If the constant is a
5147 union, we override this by getting the field from the TREE_LIST element.
5148 But the constant could also be an array. Then FIELD is zero.
5150 There is always a maximum of one element in the chain LINK for unions
5151 (even if the initializer in a source program incorrectly contains
5152 more one). */
5154 if (TREE_CODE (local.type) == RECORD_TYPE)
5155 local.field = TYPE_FIELDS (local.type);
5156 else
5157 local.field = NULL_TREE;
5159 for (cnt = 0;
5160 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5161 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5163 local.val = ce->value;
5164 local.index = NULL_TREE;
5166 /* The element in a union constructor specifies the proper field
5167 or index. */
5168 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5169 local.field = ce->index;
5171 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5172 local.index = ce->index;
5174 if (local.field && flag_verbose_asm)
5175 fprintf (asm_out_file, "%s %s:\n",
5176 ASM_COMMENT_START,
5177 DECL_NAME (local.field)
5178 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5179 : "<anonymous>");
5181 /* Eliminate the marker that makes a cast not be an lvalue. */
5182 if (local.val != NULL_TREE)
5183 STRIP_NOPS (local.val);
5185 /* Output the current element, using the appropriate helper ... */
5187 /* For an array slice not part of an outer bitfield. */
5188 if (!outer
5189 && local.index != NULL_TREE
5190 && TREE_CODE (local.index) == RANGE_EXPR)
5191 output_constructor_array_range (&local);
5193 /* For a field that is neither a true bitfield nor part of an outer one,
5194 known to be at least byte aligned and multiple-of-bytes long. */
5195 else if (!outer
5196 && (local.field == NULL_TREE
5197 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5198 output_constructor_regular_field (&local);
5200 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5201 supported for scalar fields, so we may need to convert first. */
5202 else
5204 if (TREE_CODE (local.val) == REAL_CST)
5205 local.val
5206 = fold_unary (VIEW_CONVERT_EXPR,
5207 build_nonstandard_integer_type
5208 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5209 local.val);
5210 output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5214 /* If we are not at toplevel, save the pending data for our caller.
5215 Otherwise output the pending data and padding zeros as needed. */
5216 if (outer)
5217 outer->byte = local.byte;
5218 else
5220 if (local.byte_buffer_in_use)
5222 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5223 local.total_bytes++;
5226 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5228 assemble_zeros (local.size - local.total_bytes);
5229 local.total_bytes = local.size;
5233 return local.total_bytes;
5236 /* Mark DECL as weak. */
5238 static void
5239 mark_weak (tree decl)
5241 DECL_WEAK (decl) = 1;
5243 if (DECL_RTL_SET_P (decl)
5244 && MEM_P (DECL_RTL (decl))
5245 && XEXP (DECL_RTL (decl), 0)
5246 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5247 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5250 /* Merge weak status between NEWDECL and OLDDECL. */
5252 void
5253 merge_weak (tree newdecl, tree olddecl)
5255 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5257 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5259 tree *pwd;
5260 /* We put the NEWDECL on the weak_decls list at some point
5261 and OLDDECL as well. Keep just OLDDECL on the list. */
5262 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5263 if (TREE_VALUE (*pwd) == newdecl)
5265 *pwd = TREE_CHAIN (*pwd);
5266 break;
5269 return;
5272 if (DECL_WEAK (newdecl))
5274 tree wd;
5276 /* NEWDECL is weak, but OLDDECL is not. */
5278 /* If we already output the OLDDECL, we're in trouble; we can't
5279 go back and make it weak. This should never happen in
5280 unit-at-a-time compilation. */
5281 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5283 /* If we've already generated rtl referencing OLDDECL, we may
5284 have done so in a way that will not function properly with
5285 a weak symbol. Again in unit-at-a-time this should be
5286 impossible. */
5287 gcc_assert (!TREE_USED (olddecl)
5288 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5290 if (TARGET_SUPPORTS_WEAK)
5292 /* We put the NEWDECL on the weak_decls list at some point.
5293 Replace it with the OLDDECL. */
5294 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5295 if (TREE_VALUE (wd) == newdecl)
5297 TREE_VALUE (wd) = olddecl;
5298 break;
5300 /* We may not find the entry on the list. If NEWDECL is a
5301 weak alias, then we will have already called
5302 globalize_decl to remove the entry; in that case, we do
5303 not need to do anything. */
5306 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5307 mark_weak (olddecl);
5309 else
5310 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5311 weak. Just update NEWDECL to indicate that it's weak too. */
5312 mark_weak (newdecl);
5315 /* Declare DECL to be a weak symbol. */
5317 void
5318 declare_weak (tree decl)
5320 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5321 if (! TREE_PUBLIC (decl))
5322 error ("weak declaration of %q+D must be public", decl);
5323 else if (!TARGET_SUPPORTS_WEAK)
5324 warning (0, "weak declaration of %q+D not supported", decl);
5326 mark_weak (decl);
5327 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5328 DECL_ATTRIBUTES (decl)
5329 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5332 static void
5333 weak_finish_1 (tree decl)
5335 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5336 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5337 #endif
5339 if (! TREE_USED (decl))
5340 return;
5342 #ifdef ASM_WEAKEN_DECL
5343 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5344 #else
5345 #ifdef ASM_WEAKEN_LABEL
5346 ASM_WEAKEN_LABEL (asm_out_file, name);
5347 #else
5348 #ifdef ASM_OUTPUT_WEAK_ALIAS
5350 static bool warn_once = 0;
5351 if (! warn_once)
5353 warning (0, "only weak aliases are supported in this configuration");
5354 warn_once = 1;
5356 return;
5358 #endif
5359 #endif
5360 #endif
5363 /* Fiven an assembly name, find the decl it is associated with. */
5364 static tree
5365 find_decl (tree target)
5367 symtab_node *node = symtab_node::get_for_asmname (target);
5368 if (node)
5369 return node->decl;
5370 return NULL_TREE;
5373 /* This TREE_LIST contains weakref targets. */
5375 static GTY(()) tree weakref_targets;
5377 /* Emit any pending weak declarations. */
5379 void
5380 weak_finish (void)
5382 tree t;
5384 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5386 tree alias_decl = TREE_PURPOSE (t);
5387 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5389 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5390 /* Remove alias_decl from the weak list, but leave entries for
5391 the target alone. */
5392 target = NULL_TREE;
5393 #ifndef ASM_OUTPUT_WEAKREF
5394 else if (! TREE_SYMBOL_REFERENCED (target))
5396 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5397 defined, otherwise we and weak_finish_1 would use
5398 different macros. */
5399 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5400 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5401 # else
5402 tree decl = find_decl (target);
5404 if (! decl)
5406 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5407 TREE_CODE (alias_decl), target,
5408 TREE_TYPE (alias_decl));
5410 DECL_EXTERNAL (decl) = 1;
5411 TREE_PUBLIC (decl) = 1;
5412 DECL_ARTIFICIAL (decl) = 1;
5413 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5414 TREE_USED (decl) = 1;
5417 weak_finish_1 (decl);
5418 # endif
5420 #endif
5423 tree *p;
5424 tree t2;
5426 /* Remove the alias and the target from the pending weak list
5427 so that we do not emit any .weak directives for the former,
5428 nor multiple .weak directives for the latter. */
5429 for (p = &weak_decls; (t2 = *p) ; )
5431 if (TREE_VALUE (t2) == alias_decl
5432 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5433 *p = TREE_CHAIN (t2);
5434 else
5435 p = &TREE_CHAIN (t2);
5438 /* Remove other weakrefs to the same target, to speed things up. */
5439 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5441 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5442 *p = TREE_CHAIN (t2);
5443 else
5444 p = &TREE_CHAIN (t2);
5449 for (t = weak_decls; t; t = TREE_CHAIN (t))
5451 tree decl = TREE_VALUE (t);
5453 weak_finish_1 (decl);
5457 /* Emit the assembly bits to indicate that DECL is globally visible. */
5459 static void
5460 globalize_decl (tree decl)
5463 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5464 if (DECL_WEAK (decl))
5466 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5467 tree *p, t;
5469 #ifdef ASM_WEAKEN_DECL
5470 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5471 #else
5472 ASM_WEAKEN_LABEL (asm_out_file, name);
5473 #endif
5475 /* Remove this function from the pending weak list so that
5476 we do not emit multiple .weak directives for it. */
5477 for (p = &weak_decls; (t = *p) ; )
5479 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5480 *p = TREE_CHAIN (t);
5481 else
5482 p = &TREE_CHAIN (t);
5485 /* Remove weakrefs to the same target from the pending weakref
5486 list, for the same reason. */
5487 for (p = &weakref_targets; (t = *p) ; )
5489 if (DECL_ASSEMBLER_NAME (decl)
5490 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5491 *p = TREE_CHAIN (t);
5492 else
5493 p = &TREE_CHAIN (t);
5496 return;
5498 #endif
5500 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5503 vec<alias_pair, va_gc> *alias_pairs;
5505 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5506 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5507 tree node is DECL to have the value of the tree node TARGET. */
5509 void
5510 do_assemble_alias (tree decl, tree target)
5512 /* Emulated TLS had better not get this var. */
5513 gcc_assert (!(!targetm.have_tls
5514 && TREE_CODE (decl) == VAR_DECL
5515 && DECL_THREAD_LOCAL_P (decl)));
5517 if (TREE_ASM_WRITTEN (decl))
5518 return;
5520 /* We must force creation of DECL_RTL for debug info generation, even though
5521 we don't use it here. */
5522 make_decl_rtl (decl);
5524 TREE_ASM_WRITTEN (decl) = 1;
5525 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5527 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5529 ultimate_transparent_alias_target (&target);
5531 if (!TREE_SYMBOL_REFERENCED (target))
5532 weakref_targets = tree_cons (decl, target, weakref_targets);
5534 #ifdef ASM_OUTPUT_WEAKREF
5535 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5536 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5537 IDENTIFIER_POINTER (target));
5538 #else
5539 if (!TARGET_SUPPORTS_WEAK)
5541 error_at (DECL_SOURCE_LOCATION (decl),
5542 "weakref is not supported in this configuration");
5543 return;
5545 #endif
5546 return;
5549 #ifdef ASM_OUTPUT_DEF
5550 /* Make name accessible from other files, if appropriate. */
5552 if (TREE_PUBLIC (decl))
5554 globalize_decl (decl);
5555 maybe_assemble_visibility (decl);
5557 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5559 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5560 if (targetm.has_ifunc_p ())
5561 ASM_OUTPUT_TYPE_DIRECTIVE
5562 (asm_out_file, IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5563 IFUNC_ASM_TYPE);
5564 else
5565 #endif
5566 error_at (DECL_SOURCE_LOCATION (decl),
5567 "ifunc is not supported on this target");
5570 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5571 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5572 # else
5573 ASM_OUTPUT_DEF (asm_out_file,
5574 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5575 IDENTIFIER_POINTER (target));
5576 # endif
5577 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5579 const char *name;
5580 tree *p, t;
5582 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5583 # ifdef ASM_WEAKEN_DECL
5584 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5585 # else
5586 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5587 # endif
5588 /* Remove this function from the pending weak list so that
5589 we do not emit multiple .weak directives for it. */
5590 for (p = &weak_decls; (t = *p) ; )
5591 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5592 *p = TREE_CHAIN (t);
5593 else
5594 p = &TREE_CHAIN (t);
5596 /* Remove weakrefs to the same target from the pending weakref
5597 list, for the same reason. */
5598 for (p = &weakref_targets; (t = *p) ; )
5600 if (DECL_ASSEMBLER_NAME (decl)
5601 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5602 *p = TREE_CHAIN (t);
5603 else
5604 p = &TREE_CHAIN (t);
5607 #endif
5610 /* Emit an assembler directive to make the symbol for DECL an alias to
5611 the symbol for TARGET. */
5613 void
5614 assemble_alias (tree decl, tree target)
5616 tree target_decl;
5618 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5620 tree alias = DECL_ASSEMBLER_NAME (decl);
5622 ultimate_transparent_alias_target (&target);
5624 if (alias == target)
5625 error ("weakref %q+D ultimately targets itself", decl);
5626 if (TREE_PUBLIC (decl))
5627 error ("weakref %q+D must have static linkage", decl);
5629 else
5631 #if !defined (ASM_OUTPUT_DEF)
5632 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5633 error_at (DECL_SOURCE_LOCATION (decl),
5634 "alias definitions not supported in this configuration");
5635 TREE_ASM_WRITTEN (decl) = 1;
5636 return;
5637 # else
5638 if (!DECL_WEAK (decl))
5640 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5641 error_at (DECL_SOURCE_LOCATION (decl),
5642 "ifunc is not supported in this configuration");
5643 else
5644 error_at (DECL_SOURCE_LOCATION (decl),
5645 "only weak aliases are supported in this configuration");
5646 TREE_ASM_WRITTEN (decl) = 1;
5647 return;
5649 # endif
5650 #endif
5652 TREE_USED (decl) = 1;
5654 /* Allow aliases to aliases. */
5655 if (TREE_CODE (decl) == FUNCTION_DECL)
5656 cgraph_node::get_create (decl)->alias = true;
5657 else
5658 varpool_node::get_create (decl)->alias = true;
5660 /* If the target has already been emitted, we don't have to queue the
5661 alias. This saves a tad of memory. */
5662 if (symtab->global_info_ready)
5663 target_decl = find_decl (target);
5664 else
5665 target_decl= NULL;
5666 if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5667 || symtab->state >= EXPANSION)
5668 do_assemble_alias (decl, target);
5669 else
5671 alias_pair p = {decl, target};
5672 vec_safe_push (alias_pairs, p);
5676 /* Record and output a table of translations from original function
5677 to its transaction aware clone. Note that tm_pure functions are
5678 considered to be their own clone. */
5680 static GTY((if_marked ("tree_map_marked_p"), param_is (struct tree_map)))
5681 htab_t tm_clone_hash;
5683 void
5684 record_tm_clone_pair (tree o, tree n)
5686 struct tree_map **slot, *h;
5688 if (tm_clone_hash == NULL)
5689 tm_clone_hash = htab_create_ggc (32, tree_map_hash, tree_map_eq, 0);
5691 h = ggc_alloc<tree_map> ();
5692 h->hash = htab_hash_pointer (o);
5693 h->base.from = o;
5694 h->to = n;
5696 slot = (struct tree_map **)
5697 htab_find_slot_with_hash (tm_clone_hash, h, h->hash, INSERT);
5698 *slot = h;
5701 tree
5702 get_tm_clone_pair (tree o)
5704 if (tm_clone_hash)
5706 struct tree_map *h, in;
5708 in.base.from = o;
5709 in.hash = htab_hash_pointer (o);
5710 h = (struct tree_map *) htab_find_with_hash (tm_clone_hash,
5711 &in, in.hash);
5712 if (h)
5713 return h->to;
5715 return NULL_TREE;
5718 typedef struct tm_alias_pair
5720 unsigned int uid;
5721 tree from;
5722 tree to;
5723 } tm_alias_pair;
5726 /* Helper function for finish_tm_clone_pairs. Dump a hash table entry
5727 into a VEC in INFO. */
5729 static int
5730 dump_tm_clone_to_vec (void **slot, void *info)
5732 struct tree_map *map = (struct tree_map *) *slot;
5733 vec<tm_alias_pair> *tm_alias_pairs = (vec<tm_alias_pair> *) info;
5734 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
5735 tm_alias_pairs->safe_push (p);
5736 return 1;
5739 /* Dump the actual pairs to the .tm_clone_table section. */
5741 static void
5742 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
5744 unsigned i;
5745 tm_alias_pair *p;
5746 bool switched = false;
5748 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
5750 tree src = p->from;
5751 tree dst = p->to;
5752 struct cgraph_node *src_n = cgraph_node::get (src);
5753 struct cgraph_node *dst_n = cgraph_node::get (dst);
5755 /* The function ipa_tm_create_version() marks the clone as needed if
5756 the original function was needed. But we also mark the clone as
5757 needed if we ever called the clone indirectly through
5758 TM_GETTMCLONE. If neither of these are true, we didn't generate
5759 a clone, and we didn't call it indirectly... no sense keeping it
5760 in the clone table. */
5761 if (!dst_n || !dst_n->definition)
5762 continue;
5764 /* This covers the case where we have optimized the original
5765 function away, and only access the transactional clone. */
5766 if (!src_n || !src_n->definition)
5767 continue;
5769 if (!switched)
5771 switch_to_section (targetm.asm_out.tm_clone_table_section ());
5772 assemble_align (POINTER_SIZE);
5773 switched = true;
5776 assemble_integer (XEXP (DECL_RTL (src), 0),
5777 POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
5778 assemble_integer (XEXP (DECL_RTL (dst), 0),
5779 POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
5783 /* Provide a default for the tm_clone_table section. */
5785 section *
5786 default_clone_table_section (void)
5788 return get_named_section (NULL, ".tm_clone_table", 3);
5791 /* Helper comparison function for qsorting by the DECL_UID stored in
5792 alias_pair->emitted_diags. */
5794 static int
5795 tm_alias_pair_cmp (const void *x, const void *y)
5797 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
5798 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
5799 if (p1->uid < p2->uid)
5800 return -1;
5801 if (p1->uid > p2->uid)
5802 return 1;
5803 return 0;
5806 void
5807 finish_tm_clone_pairs (void)
5809 vec<tm_alias_pair> tm_alias_pairs = vNULL;
5811 if (tm_clone_hash == NULL)
5812 return;
5814 /* We need a determenistic order for the .tm_clone_table, otherwise
5815 we will get bootstrap comparison failures, so dump the hash table
5816 to a vector, sort it, and dump the vector. */
5818 /* Dump the hashtable to a vector. */
5819 htab_traverse_noresize (tm_clone_hash, dump_tm_clone_to_vec,
5820 (void *) &tm_alias_pairs);
5821 /* Sort it. */
5822 tm_alias_pairs.qsort (tm_alias_pair_cmp);
5824 /* Dump it. */
5825 dump_tm_clone_pairs (tm_alias_pairs);
5827 htab_delete (tm_clone_hash);
5828 tm_clone_hash = NULL;
5829 tm_alias_pairs.release ();
5833 /* Emit an assembler directive to set symbol for DECL visibility to
5834 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
5836 void
5837 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
5838 int vis ATTRIBUTE_UNUSED)
5840 #ifdef HAVE_GAS_HIDDEN
5841 static const char * const visibility_types[] = {
5842 NULL, "protected", "hidden", "internal"
5845 const char *name, *type;
5847 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5848 type = visibility_types[vis];
5850 fprintf (asm_out_file, "\t.%s\t", type);
5851 assemble_name (asm_out_file, name);
5852 fprintf (asm_out_file, "\n");
5853 #else
5854 if (!DECL_ARTIFICIAL (decl))
5855 warning (OPT_Wattributes, "visibility attribute not supported "
5856 "in this configuration; ignored");
5857 #endif
5860 /* A helper function to call assemble_visibility when needed for a decl. */
5863 maybe_assemble_visibility (tree decl)
5865 enum symbol_visibility vis = DECL_VISIBILITY (decl);
5867 if (vis != VISIBILITY_DEFAULT)
5869 targetm.asm_out.assemble_visibility (decl, vis);
5870 return 1;
5872 else
5873 return 0;
5876 /* Returns 1 if the target configuration supports defining public symbols
5877 so that one of them will be chosen at link time instead of generating a
5878 multiply-defined symbol error, whether through the use of weak symbols or
5879 a target-specific mechanism for having duplicates discarded. */
5882 supports_one_only (void)
5884 if (SUPPORTS_ONE_ONLY)
5885 return 1;
5886 return TARGET_SUPPORTS_WEAK;
5889 /* Set up DECL as a public symbol that can be defined in multiple
5890 translation units without generating a linker error. */
5892 void
5893 make_decl_one_only (tree decl, tree comdat_group)
5895 struct symtab_node *symbol;
5896 gcc_assert (TREE_CODE (decl) == VAR_DECL
5897 || TREE_CODE (decl) == FUNCTION_DECL);
5899 TREE_PUBLIC (decl) = 1;
5901 if (TREE_CODE (decl) == VAR_DECL)
5902 symbol = varpool_node::get_create (decl);
5903 else
5904 symbol = cgraph_node::get_create (decl);
5906 if (SUPPORTS_ONE_ONLY)
5908 #ifdef MAKE_DECL_ONE_ONLY
5909 MAKE_DECL_ONE_ONLY (decl);
5910 #endif
5911 symbol->set_comdat_group (comdat_group);
5913 else if (TREE_CODE (decl) == VAR_DECL
5914 && (DECL_INITIAL (decl) == 0
5915 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
5916 DECL_COMMON (decl) = 1;
5917 else
5919 gcc_assert (TARGET_SUPPORTS_WEAK);
5920 DECL_WEAK (decl) = 1;
5924 void
5925 init_varasm_once (void)
5927 section_htab = htab_create_ggc (31, section_entry_hash,
5928 section_entry_eq, NULL);
5929 object_block_htab = htab_create_ggc (31, object_block_entry_hash,
5930 object_block_entry_eq, NULL);
5931 const_desc_htab = htab_create_ggc (1009, const_desc_hash,
5932 const_desc_eq, NULL);
5934 const_alias_set = new_alias_set ();
5935 shared_constant_pool = create_constant_pool ();
5937 #ifdef TEXT_SECTION_ASM_OP
5938 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
5939 TEXT_SECTION_ASM_OP);
5940 #endif
5942 #ifdef DATA_SECTION_ASM_OP
5943 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5944 DATA_SECTION_ASM_OP);
5945 #endif
5947 #ifdef SDATA_SECTION_ASM_OP
5948 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5949 SDATA_SECTION_ASM_OP);
5950 #endif
5952 #ifdef READONLY_DATA_SECTION_ASM_OP
5953 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
5954 READONLY_DATA_SECTION_ASM_OP);
5955 #endif
5957 #ifdef CTORS_SECTION_ASM_OP
5958 ctors_section = get_unnamed_section (0, output_section_asm_op,
5959 CTORS_SECTION_ASM_OP);
5960 #endif
5962 #ifdef DTORS_SECTION_ASM_OP
5963 dtors_section = get_unnamed_section (0, output_section_asm_op,
5964 DTORS_SECTION_ASM_OP);
5965 #endif
5967 #ifdef BSS_SECTION_ASM_OP
5968 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5969 output_section_asm_op,
5970 BSS_SECTION_ASM_OP);
5971 #endif
5973 #ifdef SBSS_SECTION_ASM_OP
5974 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5975 output_section_asm_op,
5976 SBSS_SECTION_ASM_OP);
5977 #endif
5979 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5980 | SECTION_COMMON, emit_tls_common);
5981 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5982 | SECTION_COMMON, emit_local);
5983 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5984 | SECTION_COMMON, emit_common);
5986 #if defined ASM_OUTPUT_ALIGNED_BSS
5987 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
5988 emit_bss);
5989 #endif
5991 targetm.asm_out.init_sections ();
5993 if (readonly_data_section == NULL)
5994 readonly_data_section = text_section;
5996 #ifdef ASM_OUTPUT_EXTERNAL
5997 pending_assemble_externals_set = new hash_set<tree>;
5998 #endif
6001 enum tls_model
6002 decl_default_tls_model (const_tree decl)
6004 enum tls_model kind;
6005 bool is_local;
6007 is_local = targetm.binds_local_p (decl);
6008 if (!flag_shlib)
6010 if (is_local)
6011 kind = TLS_MODEL_LOCAL_EXEC;
6012 else
6013 kind = TLS_MODEL_INITIAL_EXEC;
6016 /* Local dynamic is inefficient when we're not combining the
6017 parts of the address. */
6018 else if (optimize && is_local)
6019 kind = TLS_MODEL_LOCAL_DYNAMIC;
6020 else
6021 kind = TLS_MODEL_GLOBAL_DYNAMIC;
6022 if (kind < flag_tls_default)
6023 kind = flag_tls_default;
6025 return kind;
6028 /* Select a set of attributes for section NAME based on the properties
6029 of DECL and whether or not RELOC indicates that DECL's initializer
6030 might contain runtime relocations.
6032 We make the section read-only and executable for a function decl,
6033 read-only for a const data decl, and writable for a non-const data decl. */
6035 unsigned int
6036 default_section_type_flags (tree decl, const char *name, int reloc)
6038 unsigned int flags;
6040 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6041 flags = SECTION_CODE;
6042 else if (decl)
6044 enum section_category category
6045 = categorize_decl_for_section (decl, reloc);
6046 if (decl_readonly_section_1 (category))
6047 flags = 0;
6048 else if (category == SECCAT_DATA_REL_RO
6049 || category == SECCAT_DATA_REL_RO_LOCAL)
6050 flags = SECTION_WRITE | SECTION_RELRO;
6051 else
6052 flags = SECTION_WRITE;
6054 else
6056 flags = SECTION_WRITE;
6057 if (strcmp (name, ".data.rel.ro") == 0
6058 || strcmp (name, ".data.rel.ro.local") == 0)
6059 flags |= SECTION_RELRO;
6062 if (decl && DECL_P (decl) && DECL_COMDAT_GROUP (decl))
6063 flags |= SECTION_LINKONCE;
6065 if (strcmp (name, ".vtable_map_vars") == 0)
6066 flags |= SECTION_LINKONCE;
6068 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6069 flags |= SECTION_TLS | SECTION_WRITE;
6071 if (strcmp (name, ".bss") == 0
6072 || strncmp (name, ".bss.", 5) == 0
6073 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6074 || strcmp (name, ".sbss") == 0
6075 || strncmp (name, ".sbss.", 6) == 0
6076 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6077 flags |= SECTION_BSS;
6079 if (strcmp (name, ".tdata") == 0
6080 || strncmp (name, ".tdata.", 7) == 0
6081 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6082 flags |= SECTION_TLS;
6084 if (strcmp (name, ".tbss") == 0
6085 || strncmp (name, ".tbss.", 6) == 0
6086 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6087 flags |= SECTION_TLS | SECTION_BSS;
6089 /* These three sections have special ELF types. They are neither
6090 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
6091 want to print a section type (@progbits or @nobits). If someone
6092 is silly enough to emit code or TLS variables to one of these
6093 sections, then don't handle them specially. */
6094 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6095 && (strcmp (name, ".init_array") == 0
6096 || strcmp (name, ".fini_array") == 0
6097 || strcmp (name, ".preinit_array") == 0))
6098 flags |= SECTION_NOTYPE;
6100 return flags;
6103 /* Return true if the target supports some form of global BSS,
6104 either through bss_noswitch_section, or by selecting a BSS
6105 section in TARGET_ASM_SELECT_SECTION. */
6107 bool
6108 have_global_bss_p (void)
6110 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6113 /* Output assembly to switch to section NAME with attribute FLAGS.
6114 Four variants for common object file formats. */
6116 void
6117 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6118 unsigned int flags ATTRIBUTE_UNUSED,
6119 tree decl ATTRIBUTE_UNUSED)
6121 /* Some object formats don't support named sections at all. The
6122 front-end should already have flagged this as an error. */
6123 gcc_unreachable ();
6126 #ifndef TLS_SECTION_ASM_FLAG
6127 #define TLS_SECTION_ASM_FLAG 'T'
6128 #endif
6130 void
6131 default_elf_asm_named_section (const char *name, unsigned int flags,
6132 tree decl ATTRIBUTE_UNUSED)
6134 char flagchars[10], *f = flagchars;
6136 /* If we have already declared this section, we can use an
6137 abbreviated form to switch back to it -- unless this section is
6138 part of a COMDAT groups, in which case GAS requires the full
6139 declaration every time. */
6140 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6141 && (flags & SECTION_DECLARED))
6143 fprintf (asm_out_file, "\t.section\t%s\n", name);
6144 return;
6147 if (!(flags & SECTION_DEBUG))
6148 *f++ = 'a';
6149 if (flags & SECTION_EXCLUDE)
6150 *f++ = 'e';
6151 if (flags & SECTION_WRITE)
6152 *f++ = 'w';
6153 if (flags & SECTION_CODE)
6154 *f++ = 'x';
6155 if (flags & SECTION_SMALL)
6156 *f++ = 's';
6157 if (flags & SECTION_MERGE)
6158 *f++ = 'M';
6159 if (flags & SECTION_STRINGS)
6160 *f++ = 'S';
6161 if (flags & SECTION_TLS)
6162 *f++ = TLS_SECTION_ASM_FLAG;
6163 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6164 *f++ = 'G';
6165 *f = '\0';
6167 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6169 if (!(flags & SECTION_NOTYPE))
6171 const char *type;
6172 const char *format;
6174 if (flags & SECTION_BSS)
6175 type = "nobits";
6176 else
6177 type = "progbits";
6179 format = ",@%s";
6180 /* On platforms that use "@" as the assembly comment character,
6181 use "%" instead. */
6182 if (strcmp (ASM_COMMENT_START, "@") == 0)
6183 format = ",%%%s";
6184 fprintf (asm_out_file, format, type);
6186 if (flags & SECTION_ENTSIZE)
6187 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6188 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6190 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6191 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6192 else
6193 fprintf (asm_out_file, ",%s,comdat",
6194 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6198 putc ('\n', asm_out_file);
6201 void
6202 default_coff_asm_named_section (const char *name, unsigned int flags,
6203 tree decl ATTRIBUTE_UNUSED)
6205 char flagchars[8], *f = flagchars;
6207 if (flags & SECTION_WRITE)
6208 *f++ = 'w';
6209 if (flags & SECTION_CODE)
6210 *f++ = 'x';
6211 *f = '\0';
6213 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6216 void
6217 default_pe_asm_named_section (const char *name, unsigned int flags,
6218 tree decl)
6220 default_coff_asm_named_section (name, flags, decl);
6222 if (flags & SECTION_LINKONCE)
6224 /* Functions may have been compiled at various levels of
6225 optimization so we can't use `same_size' here.
6226 Instead, have the linker pick one. */
6227 fprintf (asm_out_file, "\t.linkonce %s\n",
6228 (flags & SECTION_CODE ? "discard" : "same_size"));
6232 /* The lame default section selector. */
6234 section *
6235 default_select_section (tree decl, int reloc,
6236 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6238 if (DECL_P (decl))
6240 if (decl_readonly_section (decl, reloc))
6241 return readonly_data_section;
6243 else if (TREE_CODE (decl) == CONSTRUCTOR)
6245 if (! ((flag_pic && reloc)
6246 || !TREE_READONLY (decl)
6247 || TREE_SIDE_EFFECTS (decl)
6248 || !TREE_CONSTANT (decl)))
6249 return readonly_data_section;
6251 else if (TREE_CODE (decl) == STRING_CST)
6252 return readonly_data_section;
6253 else if (! (flag_pic && reloc))
6254 return readonly_data_section;
6256 return data_section;
6259 enum section_category
6260 categorize_decl_for_section (const_tree decl, int reloc)
6262 enum section_category ret;
6264 if (TREE_CODE (decl) == FUNCTION_DECL)
6265 return SECCAT_TEXT;
6266 else if (TREE_CODE (decl) == STRING_CST)
6268 if ((flag_sanitize & SANITIZE_ADDRESS)
6269 && asan_protect_global (CONST_CAST_TREE (decl)))
6270 /* or !flag_merge_constants */
6271 return SECCAT_RODATA;
6272 else
6273 return SECCAT_RODATA_MERGE_STR;
6275 else if (TREE_CODE (decl) == VAR_DECL)
6277 if (bss_initializer_p (decl))
6278 ret = SECCAT_BSS;
6279 else if (! TREE_READONLY (decl)
6280 || TREE_SIDE_EFFECTS (decl)
6281 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
6283 /* Here the reloc_rw_mask is not testing whether the section should
6284 be read-only or not, but whether the dynamic link will have to
6285 do something. If so, we wish to segregate the data in order to
6286 minimize cache misses inside the dynamic linker. */
6287 if (reloc & targetm.asm_out.reloc_rw_mask ())
6288 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6289 else
6290 ret = SECCAT_DATA;
6292 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6293 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6294 else if (reloc || flag_merge_constants < 2
6295 || ((flag_sanitize & SANITIZE_ADDRESS)
6296 && asan_protect_global (CONST_CAST_TREE (decl))))
6297 /* C and C++ don't allow different variables to share the same
6298 location. -fmerge-all-constants allows even that (at the
6299 expense of not conforming). */
6300 ret = SECCAT_RODATA;
6301 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6302 ret = SECCAT_RODATA_MERGE_STR_INIT;
6303 else
6304 ret = SECCAT_RODATA_MERGE_CONST;
6306 else if (TREE_CODE (decl) == CONSTRUCTOR)
6308 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6309 || TREE_SIDE_EFFECTS (decl)
6310 || ! TREE_CONSTANT (decl))
6311 ret = SECCAT_DATA;
6312 else
6313 ret = SECCAT_RODATA;
6315 else
6316 ret = SECCAT_RODATA;
6318 /* There are no read-only thread-local sections. */
6319 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6321 /* Note that this would be *just* SECCAT_BSS, except that there's
6322 no concept of a read-only thread-local-data section. */
6323 if (ret == SECCAT_BSS
6324 || (flag_zero_initialized_in_bss
6325 && initializer_zerop (DECL_INITIAL (decl))))
6326 ret = SECCAT_TBSS;
6327 else
6328 ret = SECCAT_TDATA;
6331 /* If the target uses small data sections, select it. */
6332 else if (targetm.in_small_data_p (decl))
6334 if (ret == SECCAT_BSS)
6335 ret = SECCAT_SBSS;
6336 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6337 ret = SECCAT_SRODATA;
6338 else
6339 ret = SECCAT_SDATA;
6342 return ret;
6345 static bool
6346 decl_readonly_section_1 (enum section_category category)
6348 switch (category)
6350 case SECCAT_RODATA:
6351 case SECCAT_RODATA_MERGE_STR:
6352 case SECCAT_RODATA_MERGE_STR_INIT:
6353 case SECCAT_RODATA_MERGE_CONST:
6354 case SECCAT_SRODATA:
6355 return true;
6356 default:
6357 return false;
6361 bool
6362 decl_readonly_section (const_tree decl, int reloc)
6364 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6367 /* Select a section based on the above categorization. */
6369 section *
6370 default_elf_select_section (tree decl, int reloc,
6371 unsigned HOST_WIDE_INT align)
6373 const char *sname;
6374 switch (categorize_decl_for_section (decl, reloc))
6376 case SECCAT_TEXT:
6377 /* We're not supposed to be called on FUNCTION_DECLs. */
6378 gcc_unreachable ();
6379 case SECCAT_RODATA:
6380 return readonly_data_section;
6381 case SECCAT_RODATA_MERGE_STR:
6382 return mergeable_string_section (decl, align, 0);
6383 case SECCAT_RODATA_MERGE_STR_INIT:
6384 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6385 case SECCAT_RODATA_MERGE_CONST:
6386 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6387 case SECCAT_SRODATA:
6388 sname = ".sdata2";
6389 break;
6390 case SECCAT_DATA:
6391 return data_section;
6392 case SECCAT_DATA_REL:
6393 sname = ".data.rel";
6394 break;
6395 case SECCAT_DATA_REL_LOCAL:
6396 sname = ".data.rel.local";
6397 break;
6398 case SECCAT_DATA_REL_RO:
6399 sname = ".data.rel.ro";
6400 break;
6401 case SECCAT_DATA_REL_RO_LOCAL:
6402 sname = ".data.rel.ro.local";
6403 break;
6404 case SECCAT_SDATA:
6405 sname = ".sdata";
6406 break;
6407 case SECCAT_TDATA:
6408 sname = ".tdata";
6409 break;
6410 case SECCAT_BSS:
6411 if (bss_section)
6412 return bss_section;
6413 sname = ".bss";
6414 break;
6415 case SECCAT_SBSS:
6416 sname = ".sbss";
6417 break;
6418 case SECCAT_TBSS:
6419 sname = ".tbss";
6420 break;
6421 default:
6422 gcc_unreachable ();
6425 return get_named_section (decl, sname, reloc);
6428 /* Construct a unique section name based on the decl name and the
6429 categorization performed above. */
6431 void
6432 default_unique_section (tree decl, int reloc)
6434 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6435 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6436 const char *prefix, *name, *linkonce;
6437 char *string;
6439 switch (categorize_decl_for_section (decl, reloc))
6441 case SECCAT_TEXT:
6442 prefix = one_only ? ".t" : ".text";
6443 break;
6444 case SECCAT_RODATA:
6445 case SECCAT_RODATA_MERGE_STR:
6446 case SECCAT_RODATA_MERGE_STR_INIT:
6447 case SECCAT_RODATA_MERGE_CONST:
6448 prefix = one_only ? ".r" : ".rodata";
6449 break;
6450 case SECCAT_SRODATA:
6451 prefix = one_only ? ".s2" : ".sdata2";
6452 break;
6453 case SECCAT_DATA:
6454 prefix = one_only ? ".d" : ".data";
6455 break;
6456 case SECCAT_DATA_REL:
6457 prefix = one_only ? ".d.rel" : ".data.rel";
6458 break;
6459 case SECCAT_DATA_REL_LOCAL:
6460 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6461 break;
6462 case SECCAT_DATA_REL_RO:
6463 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6464 break;
6465 case SECCAT_DATA_REL_RO_LOCAL:
6466 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6467 break;
6468 case SECCAT_SDATA:
6469 prefix = one_only ? ".s" : ".sdata";
6470 break;
6471 case SECCAT_BSS:
6472 prefix = one_only ? ".b" : ".bss";
6473 break;
6474 case SECCAT_SBSS:
6475 prefix = one_only ? ".sb" : ".sbss";
6476 break;
6477 case SECCAT_TDATA:
6478 prefix = one_only ? ".td" : ".tdata";
6479 break;
6480 case SECCAT_TBSS:
6481 prefix = one_only ? ".tb" : ".tbss";
6482 break;
6483 default:
6484 gcc_unreachable ();
6487 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
6488 name = targetm.strip_name_encoding (name);
6490 /* If we're using one_only, then there needs to be a .gnu.linkonce
6491 prefix to the section name. */
6492 linkonce = one_only ? ".gnu.linkonce" : "";
6494 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6496 set_decl_section_name (decl, string);
6499 /* Like compute_reloc_for_constant, except for an RTX. The return value
6500 is a mask for which bit 1 indicates a global relocation, and bit 0
6501 indicates a local relocation. */
6503 static int
6504 compute_reloc_for_rtx_1 (rtx *xp, void *data)
6506 int *preloc = (int *) data;
6507 rtx x = *xp;
6509 switch (GET_CODE (x))
6511 case SYMBOL_REF:
6512 *preloc |= SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6513 break;
6514 case LABEL_REF:
6515 *preloc |= 1;
6516 break;
6517 default:
6518 break;
6521 return 0;
6524 static int
6525 compute_reloc_for_rtx (rtx x)
6527 int reloc;
6529 switch (GET_CODE (x))
6531 case CONST:
6532 case SYMBOL_REF:
6533 case LABEL_REF:
6534 reloc = 0;
6535 for_each_rtx (&x, compute_reloc_for_rtx_1, &reloc);
6536 return reloc;
6538 default:
6539 return 0;
6543 section *
6544 default_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
6545 rtx x,
6546 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6548 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6549 return data_section;
6550 else
6551 return readonly_data_section;
6554 section *
6555 default_elf_select_rtx_section (enum machine_mode mode, rtx x,
6556 unsigned HOST_WIDE_INT align)
6558 int reloc = compute_reloc_for_rtx (x);
6560 /* ??? Handle small data here somehow. */
6562 if (reloc & targetm.asm_out.reloc_rw_mask ())
6564 if (reloc == 1)
6565 return get_named_section (NULL, ".data.rel.ro.local", 1);
6566 else
6567 return get_named_section (NULL, ".data.rel.ro", 3);
6570 return mergeable_constant_section (mode, align, 0);
6573 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6575 void
6576 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6578 rtx symbol;
6579 int flags;
6581 /* Careful not to prod global register variables. */
6582 if (!MEM_P (rtl))
6583 return;
6584 symbol = XEXP (rtl, 0);
6585 if (GET_CODE (symbol) != SYMBOL_REF)
6586 return;
6588 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6589 if (TREE_CODE (decl) == FUNCTION_DECL)
6590 flags |= SYMBOL_FLAG_FUNCTION;
6591 if (targetm.binds_local_p (decl))
6592 flags |= SYMBOL_FLAG_LOCAL;
6593 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6594 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6595 else if (targetm.in_small_data_p (decl))
6596 flags |= SYMBOL_FLAG_SMALL;
6597 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6598 being PUBLIC, the thing *must* be defined in this translation unit.
6599 Prevent this buglet from being propagated into rtl code as well. */
6600 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6601 flags |= SYMBOL_FLAG_EXTERNAL;
6603 SYMBOL_REF_FLAGS (symbol) = flags;
6606 /* By default, we do nothing for encode_section_info, so we need not
6607 do anything but discard the '*' marker. */
6609 const char *
6610 default_strip_name_encoding (const char *str)
6612 return str + (*str == '*');
6615 #ifdef ASM_OUTPUT_DEF
6616 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6617 anchor relative to ".", the current section position. */
6619 void
6620 default_asm_output_anchor (rtx symbol)
6622 char buffer[100];
6624 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6625 SYMBOL_REF_BLOCK_OFFSET (symbol));
6626 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6628 #endif
6630 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6632 bool
6633 default_use_anchors_for_symbol_p (const_rtx symbol)
6635 section *sect;
6636 tree decl;
6638 /* Don't use anchors for mergeable sections. The linker might move
6639 the objects around. */
6640 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6641 if (sect->common.flags & SECTION_MERGE)
6642 return false;
6644 /* Don't use anchors for small data sections. The small data register
6645 acts as an anchor for such sections. */
6646 if (sect->common.flags & SECTION_SMALL)
6647 return false;
6649 decl = SYMBOL_REF_DECL (symbol);
6650 if (decl && DECL_P (decl))
6652 /* Don't use section anchors for decls that might be defined or
6653 usurped by other modules. */
6654 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6655 return false;
6657 /* Don't use section anchors for decls that will be placed in a
6658 small data section. */
6659 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6660 one above. The problem is that we only use SECTION_SMALL for
6661 sections that should be marked as small in the section directive. */
6662 if (targetm.in_small_data_p (decl))
6663 return false;
6665 return true;
6668 /* Return true when RESOLUTION indicate that symbol will be bound to the
6669 definition provided by current .o file. */
6671 static bool
6672 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
6674 return (resolution == LDPR_PREVAILING_DEF
6675 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6676 || resolution == LDPR_PREVAILING_DEF_IRONLY);
6679 /* Return true when RESOLUTION indicate that symbol will be bound locally
6680 within current executable or DSO. */
6682 static bool
6683 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
6685 return (resolution == LDPR_PREVAILING_DEF
6686 || resolution == LDPR_PREVAILING_DEF_IRONLY
6687 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6688 || resolution == LDPR_PREEMPTED_REG
6689 || resolution == LDPR_PREEMPTED_IR
6690 || resolution == LDPR_RESOLVED_IR
6691 || resolution == LDPR_RESOLVED_EXEC);
6694 /* Assume ELF-ish defaults, since that's pretty much the most liberal
6695 wrt cross-module name binding. */
6697 bool
6698 default_binds_local_p (const_tree exp)
6700 return default_binds_local_p_1 (exp, flag_shlib);
6703 bool
6704 default_binds_local_p_1 (const_tree exp, int shlib)
6706 bool local_p;
6707 bool resolved_locally = false;
6708 bool resolved_to_local_def = false;
6710 /* With resolution file in hands, take look into resolutions.
6711 We can't just return true for resolved_locally symbols,
6712 because dynamic linking might overwrite symbols
6713 in shared libraries. */
6714 if (TREE_CODE (exp) == VAR_DECL && TREE_PUBLIC (exp)
6715 && (TREE_STATIC (exp) || DECL_EXTERNAL (exp)))
6717 varpool_node *vnode = varpool_node::get (exp);
6718 if (vnode && (resolution_local_p (vnode->resolution) || vnode->in_other_partition))
6719 resolved_locally = true;
6720 if (vnode
6721 && resolution_to_local_definition_p (vnode->resolution))
6722 resolved_to_local_def = true;
6724 else if (TREE_CODE (exp) == FUNCTION_DECL && TREE_PUBLIC (exp))
6726 struct cgraph_node *node = cgraph_node::get (exp);
6727 if (node
6728 && (resolution_local_p (node->resolution) || node->in_other_partition))
6729 resolved_locally = true;
6730 if (node
6731 && resolution_to_local_definition_p (node->resolution))
6732 resolved_to_local_def = true;
6735 /* A non-decl is an entry in the constant pool. */
6736 if (!DECL_P (exp))
6737 local_p = true;
6738 /* Weakrefs may not bind locally, even though the weakref itself is always
6739 static and therefore local. Similarly, the resolver for ifunc functions
6740 might resolve to a non-local function.
6741 FIXME: We can resolve the weakref case more curefuly by looking at the
6742 weakref alias. */
6743 else if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
6744 || (TREE_CODE (exp) == FUNCTION_DECL
6745 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
6746 local_p = false;
6747 /* Static variables are always local. */
6748 else if (! TREE_PUBLIC (exp))
6749 local_p = true;
6750 /* A variable is local if the user has said explicitly that it will
6751 be. */
6752 else if ((DECL_VISIBILITY_SPECIFIED (exp)
6753 || resolved_to_local_def)
6754 && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6755 local_p = true;
6756 /* Variables defined outside this object might not be local. */
6757 else if (DECL_EXTERNAL (exp) && !resolved_locally)
6758 local_p = false;
6759 /* If defined in this object and visibility is not default, must be
6760 local. */
6761 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6762 local_p = true;
6763 /* Default visibility weak data can be overridden by a strong symbol
6764 in another module and so are not local. */
6765 else if (DECL_WEAK (exp)
6766 && !resolved_locally)
6767 local_p = false;
6768 /* If PIC, then assume that any global name can be overridden by
6769 symbols resolved from other modules. */
6770 else if (shlib)
6771 local_p = false;
6772 /* Uninitialized COMMON variable may be unified with symbols
6773 resolved from other modules. */
6774 else if (DECL_COMMON (exp)
6775 && !resolved_locally
6776 && (DECL_INITIAL (exp) == NULL
6777 || (!in_lto_p && DECL_INITIAL (exp) == error_mark_node)))
6778 local_p = false;
6779 /* Otherwise we're left with initialized (or non-common) global data
6780 which is of necessity defined locally. */
6781 else
6782 local_p = true;
6784 return local_p;
6787 /* Return true when references to DECL must bind to current definition in
6788 final executable.
6790 The condition is usually equivalent to whether the function binds to the
6791 current module (shared library or executable), that is to binds_local_p.
6792 We use this fact to avoid need for another target hook and implement
6793 the logic using binds_local_p and just special cases where
6794 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
6795 the weak definitions (that can be overwritten at linktime by other
6796 definition from different object file) and when resolution info is available
6797 we simply use the knowledge passed to us by linker plugin. */
6798 bool
6799 decl_binds_to_current_def_p (const_tree decl)
6801 gcc_assert (DECL_P (decl));
6802 if (!targetm.binds_local_p (decl))
6803 return false;
6804 if (!TREE_PUBLIC (decl))
6805 return true;
6806 /* When resolution is available, just use it. */
6807 if (TREE_CODE (decl) == VAR_DECL
6808 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl)))
6810 varpool_node *vnode = varpool_node::get (decl);
6811 if (vnode
6812 && vnode->resolution != LDPR_UNKNOWN)
6813 return resolution_to_local_definition_p (vnode->resolution);
6815 else if (TREE_CODE (decl) == FUNCTION_DECL)
6817 struct cgraph_node *node = cgraph_node::get (decl);
6818 if (node
6819 && node->resolution != LDPR_UNKNOWN)
6820 return resolution_to_local_definition_p (node->resolution);
6822 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
6823 binds locally but still can be overwritten), DECL_COMMON (can be merged
6824 with a non-common definition somewhere in the same module) or
6825 DECL_EXTERNAL.
6826 This rely on fact that binds_local_p behave as decl_replaceable_p
6827 for all other declaration types. */
6828 if (DECL_WEAK (decl))
6829 return false;
6830 if (DECL_COMMON (decl)
6831 && (DECL_INITIAL (decl) == NULL
6832 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
6833 return false;
6834 if (DECL_EXTERNAL (decl))
6835 return false;
6836 return true;
6839 /* A replaceable function or variable is one which may be replaced
6840 at link-time with an entirely different definition, provided that the
6841 replacement has the same type. For example, functions declared
6842 with __attribute__((weak)) on most systems are replaceable.
6844 COMDAT functions are not replaceable, since all definitions of the
6845 function must be equivalent. It is important that COMDAT functions
6846 not be treated as replaceable so that use of C++ template
6847 instantiations is not penalized. */
6849 bool
6850 decl_replaceable_p (tree decl)
6852 gcc_assert (DECL_P (decl));
6853 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
6854 return false;
6855 if (!flag_semantic_interposition
6856 && !DECL_WEAK (decl))
6857 return false;
6858 return !decl_binds_to_current_def_p (decl);
6861 /* Default function to output code that will globalize a label. A
6862 target must define GLOBAL_ASM_OP or provide its own function to
6863 globalize a label. */
6864 #ifdef GLOBAL_ASM_OP
6865 void
6866 default_globalize_label (FILE * stream, const char *name)
6868 fputs (GLOBAL_ASM_OP, stream);
6869 assemble_name (stream, name);
6870 putc ('\n', stream);
6872 #endif /* GLOBAL_ASM_OP */
6874 /* Default function to output code that will globalize a declaration. */
6875 void
6876 default_globalize_decl_name (FILE * stream, tree decl)
6878 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
6879 targetm.asm_out.globalize_label (stream, name);
6882 /* Default function to output a label for unwind information. The
6883 default is to do nothing. A target that needs nonlocal labels for
6884 unwind information must provide its own function to do this. */
6885 void
6886 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
6887 tree decl ATTRIBUTE_UNUSED,
6888 int for_eh ATTRIBUTE_UNUSED,
6889 int empty ATTRIBUTE_UNUSED)
6893 /* Default function to output a label to divide up the exception table.
6894 The default is to do nothing. A target that needs/wants to divide
6895 up the table must provide it's own function to do this. */
6896 void
6897 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
6901 /* This is how to output an internal numbered label where PREFIX is
6902 the class of label and LABELNO is the number within the class. */
6904 void
6905 default_generate_internal_label (char *buf, const char *prefix,
6906 unsigned long labelno)
6908 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6911 /* This is how to output an internal numbered label where PREFIX is
6912 the class of label and LABELNO is the number within the class. */
6914 void
6915 default_internal_label (FILE *stream, const char *prefix,
6916 unsigned long labelno)
6918 char *const buf = (char *) alloca (40 + strlen (prefix));
6919 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6920 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
6924 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
6926 void
6927 default_asm_declare_constant_name (FILE *file, const char *name,
6928 const_tree exp ATTRIBUTE_UNUSED,
6929 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
6931 assemble_label (file, name);
6934 /* This is the default behavior at the beginning of a file. It's
6935 controlled by two other target-hook toggles. */
6936 void
6937 default_file_start (void)
6939 if (targetm.asm_file_start_app_off
6940 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
6941 fputs (ASM_APP_OFF, asm_out_file);
6943 if (targetm.asm_file_start_file_directive)
6944 output_file_directive (asm_out_file, main_input_filename);
6947 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
6948 which emits a special section directive used to indicate whether or
6949 not this object file needs an executable stack. This is primarily
6950 a GNU extension to ELF but could be used on other targets. */
6952 int trampolines_created;
6954 void
6955 file_end_indicate_exec_stack (void)
6957 unsigned int flags = SECTION_DEBUG;
6958 if (trampolines_created)
6959 flags |= SECTION_CODE;
6961 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
6964 /* Emit a special section directive to indicate that this object file
6965 was compiled with -fsplit-stack. This is used to let the linker
6966 detect calls between split-stack code and non-split-stack code, so
6967 that it can modify the split-stack code to allocate a sufficiently
6968 large stack. We emit another special section if there are any
6969 functions in this file which have the no_split_stack attribute, to
6970 prevent the linker from warning about being unable to convert the
6971 functions if they call non-split-stack code. */
6973 void
6974 file_end_indicate_split_stack (void)
6976 if (flag_split_stack)
6978 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
6979 NULL));
6980 if (saw_no_split_stack)
6981 switch_to_section (get_section (".note.GNU-no-split-stack",
6982 SECTION_DEBUG, NULL));
6986 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
6987 a get_unnamed_section callback. */
6989 void
6990 output_section_asm_op (const void *directive)
6992 fprintf (asm_out_file, "%s\n", (const char *) directive);
6995 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
6996 the current section is NEW_SECTION. */
6998 void
6999 switch_to_section (section *new_section)
7001 if (in_section == new_section)
7002 return;
7004 if (new_section->common.flags & SECTION_FORGET)
7005 in_section = NULL;
7006 else
7007 in_section = new_section;
7009 switch (SECTION_STYLE (new_section))
7011 case SECTION_NAMED:
7012 targetm.asm_out.named_section (new_section->named.name,
7013 new_section->named.common.flags,
7014 new_section->named.decl);
7015 break;
7017 case SECTION_UNNAMED:
7018 new_section->unnamed.callback (new_section->unnamed.data);
7019 break;
7021 case SECTION_NOSWITCH:
7022 gcc_unreachable ();
7023 break;
7026 new_section->common.flags |= SECTION_DECLARED;
7029 /* If block symbol SYMBOL has not yet been assigned an offset, place
7030 it at the end of its block. */
7032 void
7033 place_block_symbol (rtx symbol)
7035 unsigned HOST_WIDE_INT size, mask, offset;
7036 struct constant_descriptor_rtx *desc;
7037 unsigned int alignment;
7038 struct object_block *block;
7039 tree decl;
7041 gcc_assert (SYMBOL_REF_BLOCK (symbol));
7042 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7043 return;
7045 /* Work out the symbol's size and alignment. */
7046 if (CONSTANT_POOL_ADDRESS_P (symbol))
7048 desc = SYMBOL_REF_CONSTANT (symbol);
7049 alignment = desc->align;
7050 size = GET_MODE_SIZE (desc->mode);
7052 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7054 decl = SYMBOL_REF_DECL (symbol);
7055 alignment = DECL_ALIGN (decl);
7056 size = get_constant_size (DECL_INITIAL (decl));
7057 if ((flag_sanitize & SANITIZE_ADDRESS)
7058 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7059 && asan_protect_global (DECL_INITIAL (decl)))
7060 size += asan_red_zone_size (size);
7062 else
7064 struct symtab_node *snode;
7065 decl = SYMBOL_REF_DECL (symbol);
7067 snode = symtab_node::get (decl);
7068 if (snode->alias)
7070 rtx target = DECL_RTL (snode->ultimate_alias_target ()->decl);
7072 place_block_symbol (target);
7073 SYMBOL_REF_BLOCK_OFFSET (symbol) = SYMBOL_REF_BLOCK_OFFSET (target);
7074 return;
7076 alignment = get_variable_align (decl);
7077 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7078 if ((flag_sanitize & SANITIZE_ADDRESS)
7079 && asan_protect_global (decl))
7081 size += asan_red_zone_size (size);
7082 alignment = MAX (alignment,
7083 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7087 /* Calculate the object's offset from the start of the block. */
7088 block = SYMBOL_REF_BLOCK (symbol);
7089 mask = alignment / BITS_PER_UNIT - 1;
7090 offset = (block->size + mask) & ~mask;
7091 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7093 /* Record the block's new alignment and size. */
7094 block->alignment = MAX (block->alignment, alignment);
7095 block->size = offset + size;
7097 vec_safe_push (block->objects, symbol);
7100 /* Return the anchor that should be used to address byte offset OFFSET
7101 from the first object in BLOCK. MODEL is the TLS model used
7102 to access it. */
7105 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7106 enum tls_model model)
7108 char label[100];
7109 unsigned int begin, middle, end;
7110 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7111 rtx anchor;
7113 /* Work out the anchor's offset. Use an offset of 0 for the first
7114 anchor so that we don't pessimize the case where we take the address
7115 of a variable at the beginning of the block. This is particularly
7116 useful when a block has only one variable assigned to it.
7118 We try to place anchors RANGE bytes apart, so there can then be
7119 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7120 a ptr_mode offset. With some target settings, the lowest such
7121 anchor might be out of range for the lowest ptr_mode offset;
7122 likewise the highest anchor for the highest offset. Use anchors
7123 at the extreme ends of the ptr_mode range in such cases.
7125 All arithmetic uses unsigned integers in order to avoid
7126 signed overflow. */
7127 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7128 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7129 range = max_offset - min_offset + 1;
7130 if (range == 0)
7131 offset = 0;
7132 else
7134 bias = 1 << (GET_MODE_BITSIZE (ptr_mode) - 1);
7135 if (offset < 0)
7137 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7138 delta -= delta % range;
7139 if (delta > bias)
7140 delta = bias;
7141 offset = (HOST_WIDE_INT) (-delta);
7143 else
7145 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7146 delta -= delta % range;
7147 if (delta > bias - 1)
7148 delta = bias - 1;
7149 offset = (HOST_WIDE_INT) delta;
7153 /* Do a binary search to see if there's already an anchor we can use.
7154 Set BEGIN to the new anchor's index if not. */
7155 begin = 0;
7156 end = vec_safe_length (block->anchors);
7157 while (begin != end)
7159 middle = (end + begin) / 2;
7160 anchor = (*block->anchors)[middle];
7161 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7162 end = middle;
7163 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7164 begin = middle + 1;
7165 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7166 end = middle;
7167 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7168 begin = middle + 1;
7169 else
7170 return anchor;
7173 /* Create a new anchor with a unique label. */
7174 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7175 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7176 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7177 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7179 /* Insert it at index BEGIN. */
7180 vec_safe_insert (block->anchors, begin, anchor);
7181 return anchor;
7184 /* Output the objects in BLOCK. */
7186 static void
7187 output_object_block (struct object_block *block)
7189 struct constant_descriptor_rtx *desc;
7190 unsigned int i;
7191 HOST_WIDE_INT offset;
7192 tree decl;
7193 rtx symbol;
7195 if (!block->objects)
7196 return;
7198 /* Switch to the section and make sure that the first byte is
7199 suitably aligned. */
7200 switch_to_section (block->sect);
7201 assemble_align (block->alignment);
7203 /* Define the values of all anchors relative to the current section
7204 position. */
7205 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7206 targetm.asm_out.output_anchor (symbol);
7208 /* Output the objects themselves. */
7209 offset = 0;
7210 FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7212 /* Move to the object's offset, padding with zeros if necessary. */
7213 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7214 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7215 if (CONSTANT_POOL_ADDRESS_P (symbol))
7217 desc = SYMBOL_REF_CONSTANT (symbol);
7218 output_constant_pool_1 (desc, 1);
7219 offset += GET_MODE_SIZE (desc->mode);
7221 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7223 HOST_WIDE_INT size;
7224 decl = SYMBOL_REF_DECL (symbol);
7225 assemble_constant_contents (DECL_INITIAL (decl), XSTR (symbol, 0),
7226 DECL_ALIGN (decl));
7227 size = get_constant_size (DECL_INITIAL (decl));
7228 offset += size;
7229 if ((flag_sanitize & SANITIZE_ADDRESS)
7230 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7231 && asan_protect_global (DECL_INITIAL (decl)))
7233 size = asan_red_zone_size (size);
7234 assemble_zeros (size);
7235 offset += size;
7238 else
7240 HOST_WIDE_INT size;
7241 decl = SYMBOL_REF_DECL (symbol);
7242 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7243 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7244 offset += size;
7245 if ((flag_sanitize & SANITIZE_ADDRESS)
7246 && asan_protect_global (decl))
7248 size = asan_red_zone_size (size);
7249 assemble_zeros (size);
7250 offset += size;
7256 /* A htab_traverse callback used to call output_object_block for
7257 each member of object_block_htab. */
7259 static int
7260 output_object_block_htab (void **slot, void *data ATTRIBUTE_UNUSED)
7262 output_object_block ((struct object_block *) (*slot));
7263 return 1;
7266 /* Output the definitions of all object_blocks. */
7268 void
7269 output_object_blocks (void)
7271 htab_traverse (object_block_htab, output_object_block_htab, NULL);
7274 /* This function provides a possible implementation of the
7275 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7276 by -frecord-gcc-switches it creates a new mergeable, string section in the
7277 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7278 contains the switches in ASCII format.
7280 FIXME: This code does not correctly handle double quote characters
7281 that appear inside strings, (it strips them rather than preserving them).
7282 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7283 characters - instead it treats them as sub-string separators. Since
7284 we want to emit NUL strings terminators into the object file we have to use
7285 ASM_OUTPUT_SKIP. */
7288 elf_record_gcc_switches (print_switch_type type, const char * name)
7290 switch (type)
7292 case SWITCH_TYPE_PASSED:
7293 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7294 ASM_OUTPUT_SKIP (asm_out_file, (unsigned HOST_WIDE_INT) 1);
7295 break;
7297 case SWITCH_TYPE_DESCRIPTIVE:
7298 if (name == NULL)
7300 /* Distinguish between invocations where name is NULL. */
7301 static bool started = false;
7303 if (!started)
7305 section * sec;
7307 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7308 SECTION_DEBUG
7309 | SECTION_MERGE
7310 | SECTION_STRINGS
7311 | (SECTION_ENTSIZE & 1),
7312 NULL);
7313 switch_to_section (sec);
7314 started = true;
7318 default:
7319 break;
7322 /* The return value is currently ignored by the caller, but must be 0.
7323 For -fverbose-asm the return value would be the number of characters
7324 emitted into the assembler file. */
7325 return 0;
7328 /* Emit text to declare externally defined symbols. It is needed to
7329 properly support non-default visibility. */
7330 void
7331 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7332 tree decl,
7333 const char *name ATTRIBUTE_UNUSED)
7335 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7336 set in order to avoid putting out names that are never really
7337 used. */
7338 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7339 && targetm.binds_local_p (decl))
7340 maybe_assemble_visibility (decl);
7343 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7345 void
7346 default_asm_output_source_filename (FILE *file, const char *name)
7348 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7349 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7350 #else
7351 fprintf (file, "\t.file\t");
7352 output_quoted_string (file, name);
7353 putc ('\n', file);
7354 #endif
7357 /* Output a file name in the form wanted by System V. */
7359 void
7360 output_file_directive (FILE *asm_file, const char *input_name)
7362 int len;
7363 const char *na;
7365 if (input_name == NULL)
7366 input_name = "<stdin>";
7367 else
7368 input_name = remap_debug_filename (input_name);
7370 len = strlen (input_name);
7371 na = input_name + len;
7373 /* NA gets INPUT_NAME sans directory names. */
7374 while (na > input_name)
7376 if (IS_DIR_SEPARATOR (na[-1]))
7377 break;
7378 na--;
7381 targetm.asm_out.output_source_filename (asm_file, na);
7384 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7385 EXP. */
7387 make_debug_expr_from_rtl (const_rtx exp)
7389 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7390 enum machine_mode mode = GET_MODE (exp);
7391 rtx dval;
7393 DECL_ARTIFICIAL (ddecl) = 1;
7394 if (REG_P (exp) && REG_EXPR (exp))
7395 type = TREE_TYPE (REG_EXPR (exp));
7396 else if (MEM_P (exp) && MEM_EXPR (exp))
7397 type = TREE_TYPE (MEM_EXPR (exp));
7398 else
7399 type = NULL_TREE;
7400 if (type && TYPE_MODE (type) == mode)
7401 TREE_TYPE (ddecl) = type;
7402 else
7403 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7404 DECL_MODE (ddecl) = mode;
7405 dval = gen_rtx_DEBUG_EXPR (mode);
7406 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7407 SET_DECL_RTL (ddecl, dval);
7408 return dval;
7411 #ifdef ELF_ASCII_ESCAPES
7412 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7414 void
7415 default_elf_asm_output_limited_string (FILE *f, const char *s)
7417 int escape;
7418 unsigned char c;
7420 fputs (STRING_ASM_OP, f);
7421 putc ('"', f);
7422 while (*s != '\0')
7424 c = *s;
7425 escape = ELF_ASCII_ESCAPES[c];
7426 switch (escape)
7428 case 0:
7429 putc (c, f);
7430 break;
7431 case 1:
7432 /* TODO: Print in hex with fast function, important for -flto. */
7433 fprintf (f, "\\%03o", c);
7434 break;
7435 default:
7436 putc ('\\', f);
7437 putc (escape, f);
7438 break;
7440 s++;
7442 putc ('\"', f);
7443 putc ('\n', f);
7446 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7448 void
7449 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7451 const char *limit = s + len;
7452 const char *last_null = NULL;
7453 unsigned bytes_in_chunk = 0;
7454 unsigned char c;
7455 int escape;
7457 for (; s < limit; s++)
7459 const char *p;
7461 if (bytes_in_chunk >= 60)
7463 putc ('\"', f);
7464 putc ('\n', f);
7465 bytes_in_chunk = 0;
7468 if (s > last_null)
7470 for (p = s; p < limit && *p != '\0'; p++)
7471 continue;
7472 last_null = p;
7474 else
7475 p = last_null;
7477 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7479 if (bytes_in_chunk > 0)
7481 putc ('\"', f);
7482 putc ('\n', f);
7483 bytes_in_chunk = 0;
7486 default_elf_asm_output_limited_string (f, s);
7487 s = p;
7489 else
7491 if (bytes_in_chunk == 0)
7492 fputs (ASCII_DATA_ASM_OP "\"", f);
7494 c = *s;
7495 escape = ELF_ASCII_ESCAPES[c];
7496 switch (escape)
7498 case 0:
7499 putc (c, f);
7500 bytes_in_chunk++;
7501 break;
7502 case 1:
7503 /* TODO: Print in hex with fast function, important for -flto. */
7504 fprintf (f, "\\%03o", c);
7505 bytes_in_chunk += 4;
7506 break;
7507 default:
7508 putc ('\\', f);
7509 putc (escape, f);
7510 bytes_in_chunk += 2;
7511 break;
7517 if (bytes_in_chunk > 0)
7519 putc ('\"', f);
7520 putc ('\n', f);
7523 #endif
7525 static GTY(()) section *elf_init_array_section;
7526 static GTY(()) section *elf_fini_array_section;
7528 static section *
7529 get_elf_initfini_array_priority_section (int priority,
7530 bool constructor_p)
7532 section *sec;
7533 if (priority != DEFAULT_INIT_PRIORITY)
7535 char buf[18];
7536 sprintf (buf, "%s.%.5u",
7537 constructor_p ? ".init_array" : ".fini_array",
7538 priority);
7539 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7541 else
7543 if (constructor_p)
7545 if (elf_init_array_section == NULL)
7546 elf_init_array_section
7547 = get_section (".init_array",
7548 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7549 sec = elf_init_array_section;
7551 else
7553 if (elf_fini_array_section == NULL)
7554 elf_fini_array_section
7555 = get_section (".fini_array",
7556 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7557 sec = elf_fini_array_section;
7560 return sec;
7563 /* Use .init_array section for constructors. */
7565 void
7566 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7568 section *sec = get_elf_initfini_array_priority_section (priority,
7569 true);
7570 assemble_addr_to_section (symbol, sec);
7573 /* Use .fini_array section for destructors. */
7575 void
7576 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7578 section *sec = get_elf_initfini_array_priority_section (priority,
7579 false);
7580 assemble_addr_to_section (symbol, sec);
7583 /* Default TARGET_ASM_OUTPUT_IDENT hook.
7585 This is a bit of a cheat. The real default is a no-op, but this
7586 hook is the default for all targets with a .ident directive. */
7588 void
7589 default_asm_output_ident_directive (const char *ident_str)
7591 const char *ident_asm_op = "\t.ident\t";
7593 /* If we are still in the front end, do not write out the string
7594 to asm_out_file. Instead, add a fake top-level asm statement.
7595 This allows the front ends to use this hook without actually
7596 writing to asm_out_file, to handle #ident or Pragma Ident. */
7597 if (symtab->state == PARSING)
7599 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
7600 symtab->finalize_toplevel_asm (build_string (strlen (buf), buf));
7602 else
7603 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
7606 #include "gt-varasm.h"