* lib/scanasm.exp (hidden-scan-for): Add XCOFF support.
[official-gcc.git] / gcc / varasm.c
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1 /* Output variables, constants and external declarations, for GNU compiler.
2 Copyright (C) 1987-2016 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 "backend.h"
32 #include "target.h"
33 #include "rtl.h"
34 #include "tree.h"
35 #include "predict.h"
36 #include "memmodel.h"
37 #include "tm_p.h"
38 #include "stringpool.h"
39 #include "regs.h"
40 #include "emit-rtl.h"
41 #include "cgraph.h"
42 #include "diagnostic-core.h"
43 #include "fold-const.h"
44 #include "stor-layout.h"
45 #include "varasm.h"
46 #include "flags.h"
47 #include "stmt.h"
48 #include "expr.h"
49 #include "expmed.h"
50 #include "output.h"
51 #include "langhooks.h"
52 #include "debug.h"
53 #include "common/common-target.h"
54 #include "asan.h"
55 #include "rtl-iter.h"
57 #ifdef XCOFF_DEBUGGING_INFO
58 #include "xcoffout.h" /* Needed for external data declarations. */
59 #endif
61 /* The (assembler) name of the first globally-visible object output. */
62 extern GTY(()) const char *first_global_object_name;
63 extern GTY(()) const char *weak_global_object_name;
65 const char *first_global_object_name;
66 const char *weak_global_object_name;
68 struct addr_const;
69 struct constant_descriptor_rtx;
70 struct rtx_constant_pool;
72 #define n_deferred_constants (crtl->varasm.deferred_constants)
74 /* Number for making the label on the next
75 constant that is stored in memory. */
77 static GTY(()) int const_labelno;
79 /* Carry information from ASM_DECLARE_OBJECT_NAME
80 to ASM_FINISH_DECLARE_OBJECT. */
82 int size_directive_output;
84 /* The last decl for which assemble_variable was called,
85 if it did ASM_DECLARE_OBJECT_NAME.
86 If the last call to assemble_variable didn't do that,
87 this holds 0. */
89 tree last_assemble_variable_decl;
91 /* The following global variable indicates if the first basic block
92 in a function belongs to the cold partition or not. */
94 bool first_function_block_is_cold;
96 /* Whether we saw any functions with no_split_stack. */
98 static bool saw_no_split_stack;
100 static const char *strip_reg_name (const char *);
101 static int contains_pointers_p (tree);
102 #ifdef ASM_OUTPUT_EXTERNAL
103 static bool incorporeal_function_p (tree);
104 #endif
105 static void decode_addr_const (tree, struct addr_const *);
106 static hashval_t const_hash_1 (const tree);
107 static int compare_constant (const tree, const tree);
108 static void output_constant_def_contents (rtx);
109 static void output_addressed_constants (tree);
110 static unsigned HOST_WIDE_INT output_constant (tree, unsigned HOST_WIDE_INT,
111 unsigned int, bool);
112 static void globalize_decl (tree);
113 static bool decl_readonly_section_1 (enum section_category);
114 #ifdef BSS_SECTION_ASM_OP
115 #ifdef ASM_OUTPUT_ALIGNED_BSS
116 static void asm_output_aligned_bss (FILE *, tree, const char *,
117 unsigned HOST_WIDE_INT, int)
118 ATTRIBUTE_UNUSED;
119 #endif
120 #endif /* BSS_SECTION_ASM_OP */
121 static void mark_weak (tree);
122 static void output_constant_pool (const char *, tree);
123 static void handle_vtv_comdat_section (section *, const_tree);
125 /* Well-known sections, each one associated with some sort of *_ASM_OP. */
126 section *text_section;
127 section *data_section;
128 section *readonly_data_section;
129 section *sdata_section;
130 section *ctors_section;
131 section *dtors_section;
132 section *bss_section;
133 section *sbss_section;
135 /* Various forms of common section. All are guaranteed to be nonnull. */
136 section *tls_comm_section;
137 section *comm_section;
138 section *lcomm_section;
140 /* A SECTION_NOSWITCH section used for declaring global BSS variables.
141 May be null. */
142 section *bss_noswitch_section;
144 /* The section that holds the main exception table, when known. The section
145 is set either by the target's init_sections hook or by the first call to
146 switch_to_exception_section. */
147 section *exception_section;
149 /* The section that holds the DWARF2 frame unwind information, when known.
150 The section is set either by the target's init_sections hook or by the
151 first call to switch_to_eh_frame_section. */
152 section *eh_frame_section;
154 /* asm_out_file's current section. This is NULL if no section has yet
155 been selected or if we lose track of what the current section is. */
156 section *in_section;
158 /* True if code for the current function is currently being directed
159 at the cold section. */
160 bool in_cold_section_p;
162 /* The following global holds the "function name" for the code in the
163 cold section of a function, if hot/cold function splitting is enabled
164 and there was actually code that went into the cold section. A
165 pseudo function name is needed for the cold section of code for some
166 debugging tools that perform symbolization. */
167 tree cold_function_name = NULL_TREE;
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 (VAR_OR_FUNCTION_DECL_P (DECL) && DECL_SECTION_NAME (DECL) != NULL)
176 struct section_hasher : ggc_ptr_hash<section>
178 typedef const char *compare_type;
180 static hashval_t hash (section *);
181 static bool equal (section *, const char *);
184 /* Hash table of named sections. */
185 static GTY(()) hash_table<section_hasher> *section_htab;
187 struct object_block_hasher : ggc_ptr_hash<object_block>
189 typedef const section *compare_type;
191 static hashval_t hash (object_block *);
192 static bool equal (object_block *, const section *);
195 /* A table of object_blocks, indexed by section. */
196 static GTY(()) hash_table<object_block_hasher> *object_block_htab;
198 /* The next number to use for internal anchor labels. */
199 static GTY(()) int anchor_labelno;
201 /* A pool of constants that can be shared between functions. */
202 static GTY(()) struct rtx_constant_pool *shared_constant_pool;
204 /* Helper routines for maintaining section_htab. */
206 bool
207 section_hasher::equal (section *old, const char *new_name)
209 return strcmp (old->named.name, new_name) == 0;
212 hashval_t
213 section_hasher::hash (section *old)
215 return htab_hash_string (old->named.name);
218 /* Return a hash value for section SECT. */
220 static hashval_t
221 hash_section (section *sect)
223 if (sect->common.flags & SECTION_NAMED)
224 return htab_hash_string (sect->named.name);
225 return sect->common.flags;
228 /* Helper routines for maintaining object_block_htab. */
230 inline bool
231 object_block_hasher::equal (object_block *old, const section *new_section)
233 return old->sect == new_section;
236 hashval_t
237 object_block_hasher::hash (object_block *old)
239 return hash_section (old->sect);
242 /* Return a new unnamed section with the given fields. */
244 section *
245 get_unnamed_section (unsigned int flags, void (*callback) (const void *),
246 const void *data)
248 section *sect;
250 sect = ggc_alloc<section> ();
251 sect->unnamed.common.flags = flags | SECTION_UNNAMED;
252 sect->unnamed.callback = callback;
253 sect->unnamed.data = data;
254 sect->unnamed.next = unnamed_sections;
256 unnamed_sections = sect;
257 return sect;
260 /* Return a SECTION_NOSWITCH section with the given fields. */
262 static section *
263 get_noswitch_section (unsigned int flags, noswitch_section_callback callback)
265 section *sect;
267 sect = ggc_alloc<section> ();
268 sect->noswitch.common.flags = flags | SECTION_NOSWITCH;
269 sect->noswitch.callback = callback;
271 return sect;
274 /* Return the named section structure associated with NAME. Create
275 a new section with the given fields if no such structure exists. */
277 section *
278 get_section (const char *name, unsigned int flags, tree decl)
280 section *sect, **slot;
282 slot = section_htab->find_slot_with_hash (name, htab_hash_string (name),
283 INSERT);
284 flags |= SECTION_NAMED;
285 if (*slot == NULL)
287 sect = ggc_alloc<section> ();
288 sect->named.common.flags = flags;
289 sect->named.name = ggc_strdup (name);
290 sect->named.decl = decl;
291 *slot = sect;
293 else
295 sect = *slot;
296 if ((sect->common.flags & ~SECTION_DECLARED) != flags
297 && ((sect->common.flags | flags) & SECTION_OVERRIDE) == 0)
299 /* It is fine if one of the section flags is
300 SECTION_WRITE | SECTION_RELRO and the other has none of these
301 flags (i.e. read-only) in named sections and either the
302 section hasn't been declared yet or has been declared as writable.
303 In that case just make sure the resulting flags are
304 SECTION_WRITE | SECTION_RELRO, ie. writable only because of
305 relocations. */
306 if (((sect->common.flags ^ flags) & (SECTION_WRITE | SECTION_RELRO))
307 == (SECTION_WRITE | SECTION_RELRO)
308 && (sect->common.flags
309 & ~(SECTION_DECLARED | SECTION_WRITE | SECTION_RELRO))
310 == (flags & ~(SECTION_WRITE | SECTION_RELRO))
311 && ((sect->common.flags & SECTION_DECLARED) == 0
312 || (sect->common.flags & SECTION_WRITE)))
314 sect->common.flags |= (SECTION_WRITE | SECTION_RELRO);
315 return sect;
317 /* Sanity check user variables for flag changes. */
318 if (sect->named.decl != NULL
319 && DECL_P (sect->named.decl)
320 && decl != sect->named.decl)
322 if (decl != NULL && DECL_P (decl))
323 error ("%+D causes a section type conflict with %D",
324 decl, sect->named.decl);
325 else
326 error ("section type conflict with %D", sect->named.decl);
327 inform (DECL_SOURCE_LOCATION (sect->named.decl),
328 "%qD was declared here", sect->named.decl);
330 else if (decl != NULL && DECL_P (decl))
331 error ("%+D causes a section type conflict", decl);
332 else
333 error ("section type conflict");
334 /* Make sure we don't error about one section multiple times. */
335 sect->common.flags |= SECTION_OVERRIDE;
338 return sect;
341 /* Return true if the current compilation mode benefits from having
342 objects grouped into blocks. */
344 static bool
345 use_object_blocks_p (void)
347 return flag_section_anchors;
350 /* Return the object_block structure for section SECT. Create a new
351 structure if we haven't created one already. Return null if SECT
352 itself is null. */
354 static struct object_block *
355 get_block_for_section (section *sect)
357 struct object_block *block;
359 if (sect == NULL)
360 return NULL;
362 object_block **slot
363 = object_block_htab->find_slot_with_hash (sect, hash_section (sect),
364 INSERT);
365 block = *slot;
366 if (block == NULL)
368 block = ggc_cleared_alloc<object_block> ();
369 block->sect = sect;
370 *slot = block;
372 return block;
375 /* Create a symbol with label LABEL and place it at byte offset
376 OFFSET in BLOCK. OFFSET can be negative if the symbol's offset
377 is not yet known. LABEL must be a garbage-collected string. */
379 static rtx
380 create_block_symbol (const char *label, struct object_block *block,
381 HOST_WIDE_INT offset)
383 rtx symbol;
384 unsigned int size;
386 /* Create the extended SYMBOL_REF. */
387 size = RTX_HDR_SIZE + sizeof (struct block_symbol);
388 symbol = (rtx) ggc_internal_alloc (size);
390 /* Initialize the normal SYMBOL_REF fields. */
391 memset (symbol, 0, size);
392 PUT_CODE (symbol, SYMBOL_REF);
393 PUT_MODE (symbol, Pmode);
394 XSTR (symbol, 0) = label;
395 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_HAS_BLOCK_INFO;
397 /* Initialize the block_symbol stuff. */
398 SYMBOL_REF_BLOCK (symbol) = block;
399 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
401 return symbol;
404 /* Return a section with a particular name and with whatever SECTION_*
405 flags section_type_flags deems appropriate. The name of the section
406 is taken from NAME if nonnull, otherwise it is taken from DECL's
407 DECL_SECTION_NAME. DECL is the decl associated with the section
408 (see the section comment for details) and RELOC is as for
409 section_type_flags. */
411 section *
412 get_named_section (tree decl, const char *name, int reloc)
414 unsigned int flags;
416 if (name == NULL)
418 gcc_assert (decl && DECL_P (decl) && DECL_SECTION_NAME (decl));
419 name = DECL_SECTION_NAME (decl);
422 flags = targetm.section_type_flags (decl, name, reloc);
423 return get_section (name, flags, decl);
426 /* Worker for resolve_unique_section. */
428 static bool
429 set_implicit_section (struct symtab_node *n, void *data ATTRIBUTE_UNUSED)
431 n->implicit_section = true;
432 return false;
435 /* If required, set DECL_SECTION_NAME to a unique name. */
437 void
438 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
439 int flag_function_or_data_sections)
441 if (DECL_SECTION_NAME (decl) == NULL
442 && targetm_common.have_named_sections
443 && (flag_function_or_data_sections
444 || DECL_COMDAT_GROUP (decl)))
446 targetm.asm_out.unique_section (decl, reloc);
447 if (DECL_SECTION_NAME (decl))
448 symtab_node::get (decl)->call_for_symbol_and_aliases
449 (set_implicit_section, NULL, true);
453 #ifdef BSS_SECTION_ASM_OP
455 #ifdef ASM_OUTPUT_ALIGNED_BSS
457 /* Utility function for targets to use in implementing
458 ASM_OUTPUT_ALIGNED_BSS.
459 ??? It is believed that this function will work in most cases so such
460 support is localized here. */
462 static void
463 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
464 const char *name, unsigned HOST_WIDE_INT size,
465 int align)
467 switch_to_section (bss_section);
468 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
469 #ifdef ASM_DECLARE_OBJECT_NAME
470 last_assemble_variable_decl = decl;
471 ASM_DECLARE_OBJECT_NAME (file, name, decl);
472 #else
473 /* Standard thing is just output label for the object. */
474 ASM_OUTPUT_LABEL (file, name);
475 #endif /* ASM_DECLARE_OBJECT_NAME */
476 ASM_OUTPUT_SKIP (file, size ? size : 1);
479 #endif
481 #endif /* BSS_SECTION_ASM_OP */
483 #ifndef USE_SELECT_SECTION_FOR_FUNCTIONS
484 /* Return the hot section for function DECL. Return text_section for
485 null DECLs. */
487 static section *
488 hot_function_section (tree decl)
490 if (decl != NULL_TREE
491 && DECL_SECTION_NAME (decl) != NULL
492 && targetm_common.have_named_sections)
493 return get_named_section (decl, NULL, 0);
494 else
495 return text_section;
497 #endif
499 /* Return section for TEXT_SECTION_NAME if DECL or DECL_SECTION_NAME (DECL)
500 is NULL.
502 When DECL_SECTION_NAME is non-NULL and it is implicit section and
503 NAMED_SECTION_SUFFIX is non-NULL, then produce section called
504 concatenate the name with NAMED_SECTION_SUFFIX.
505 Otherwise produce "TEXT_SECTION_NAME.IMPLICIT_NAME". */
507 section *
508 get_named_text_section (tree decl,
509 const char *text_section_name,
510 const char *named_section_suffix)
512 if (decl && DECL_SECTION_NAME (decl))
514 if (named_section_suffix)
516 const char *dsn = DECL_SECTION_NAME (decl);
517 const char *stripped_name;
518 char *name, *buffer;
520 name = (char *) alloca (strlen (dsn) + 1);
521 memcpy (name, dsn,
522 strlen (dsn) + 1);
524 stripped_name = targetm.strip_name_encoding (name);
526 buffer = ACONCAT ((stripped_name, named_section_suffix, NULL));
527 return get_named_section (decl, buffer, 0);
529 else if (symtab_node::get (decl)->implicit_section)
531 const char *name;
533 /* Do not try to split gnu_linkonce functions. This gets somewhat
534 slipperly. */
535 if (DECL_COMDAT_GROUP (decl) && !HAVE_COMDAT_GROUP)
536 return NULL;
537 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
538 name = targetm.strip_name_encoding (name);
539 return get_named_section (decl, ACONCAT ((text_section_name, ".",
540 name, NULL)), 0);
542 else
543 return NULL;
545 return get_named_section (decl, text_section_name, 0);
548 /* Choose named function section based on its frequency. */
550 section *
551 default_function_section (tree decl, enum node_frequency freq,
552 bool startup, bool exit)
554 #if defined HAVE_LD_EH_GC_SECTIONS && defined HAVE_LD_EH_GC_SECTIONS_BUG
555 /* Old GNU linkers have buggy --gc-section support, which sometimes
556 results in .gcc_except_table* sections being garbage collected. */
557 if (decl
558 && symtab_node::get (decl)->implicit_section)
559 return NULL;
560 #endif
562 if (!flag_reorder_functions
563 || !targetm_common.have_named_sections)
564 return NULL;
565 /* Startup code should go to startup subsection unless it is
566 unlikely executed (this happens especially with function splitting
567 where we can split away unnecessary parts of static constructors. */
568 if (startup && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
570 /* If we do have a profile or(and) LTO phase is executed, we do not need
571 these ELF section. */
572 if (!in_lto_p || !flag_profile_values)
573 return get_named_text_section (decl, ".text.startup", NULL);
574 else
575 return NULL;
578 /* Similarly for exit. */
579 if (exit && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
580 return get_named_text_section (decl, ".text.exit", NULL);
582 /* Group cold functions together, similarly for hot code. */
583 switch (freq)
585 case NODE_FREQUENCY_UNLIKELY_EXECUTED:
586 return get_named_text_section (decl, ".text.unlikely", NULL);
587 case NODE_FREQUENCY_HOT:
588 /* If we do have a profile or(and) LTO phase is executed, we do not need
589 these ELF section. */
590 if (!in_lto_p || !flag_profile_values)
591 return get_named_text_section (decl, ".text.hot", NULL);
592 /* FALLTHRU */
593 default:
594 return NULL;
598 /* Return the section for function DECL.
600 If DECL is NULL_TREE, return the text section. We can be passed
601 NULL_TREE under some circumstances by dbxout.c at least.
603 If FORCE_COLD is true, return cold function section ignoring
604 the frequency info of cgraph_node. */
606 static section *
607 function_section_1 (tree decl, bool force_cold)
609 section *section = NULL;
610 enum node_frequency freq = NODE_FREQUENCY_NORMAL;
611 bool startup = false, exit = false;
613 if (decl)
615 struct cgraph_node *node = cgraph_node::get (decl);
617 if (node)
619 freq = node->frequency;
620 startup = node->only_called_at_startup;
621 exit = node->only_called_at_exit;
624 if (force_cold)
625 freq = NODE_FREQUENCY_UNLIKELY_EXECUTED;
627 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
628 if (decl != NULL_TREE
629 && DECL_SECTION_NAME (decl) != NULL)
631 if (targetm.asm_out.function_section)
632 section = targetm.asm_out.function_section (decl, freq,
633 startup, exit);
634 if (section)
635 return section;
636 return get_named_section (decl, NULL, 0);
638 else
639 return targetm.asm_out.select_section
640 (decl, freq == NODE_FREQUENCY_UNLIKELY_EXECUTED,
641 symtab_node::get (decl)->definition_alignment ());
642 #else
643 if (targetm.asm_out.function_section)
644 section = targetm.asm_out.function_section (decl, freq, startup, exit);
645 if (section)
646 return section;
647 return hot_function_section (decl);
648 #endif
651 /* Return the section for function DECL.
653 If DECL is NULL_TREE, return the text section. We can be passed
654 NULL_TREE under some circumstances by dbxout.c at least. */
656 section *
657 function_section (tree decl)
659 /* Handle cases where function splitting code decides
660 to put function entry point into unlikely executed section
661 despite the fact that the function itself is not cold
662 (i.e. it is called rarely but contains a hot loop that is
663 better to live in hot subsection for the code locality). */
664 return function_section_1 (decl,
665 first_function_block_is_cold);
668 /* Return the section for the current function, take IN_COLD_SECTION_P
669 into account. */
671 section *
672 current_function_section (void)
674 return function_section_1 (current_function_decl, in_cold_section_p);
677 /* Tell assembler to switch to unlikely-to-be-executed text section. */
679 section *
680 unlikely_text_section (void)
682 return function_section_1 (current_function_decl, true);
685 /* When called within a function context, return true if the function
686 has been assigned a cold text section and if SECT is that section.
687 When called outside a function context, return true if SECT is the
688 default cold section. */
690 bool
691 unlikely_text_section_p (section *sect)
693 return sect == function_section_1 (current_function_decl, true);
696 /* Return the read-only data section associated with function DECL. */
698 section *
699 default_function_rodata_section (tree decl)
701 if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
703 const char *name = DECL_SECTION_NAME (decl);
705 if (DECL_COMDAT_GROUP (decl) && HAVE_COMDAT_GROUP)
707 const char *dot;
708 size_t len;
709 char* rname;
711 dot = strchr (name + 1, '.');
712 if (!dot)
713 dot = name;
714 len = strlen (dot) + 8;
715 rname = (char *) alloca (len);
717 strcpy (rname, ".rodata");
718 strcat (rname, dot);
719 return get_section (rname, SECTION_LINKONCE, decl);
721 /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo. */
722 else if (DECL_COMDAT_GROUP (decl)
723 && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
725 size_t len = strlen (name) + 1;
726 char *rname = (char *) alloca (len);
728 memcpy (rname, name, len);
729 rname[14] = 'r';
730 return get_section (rname, SECTION_LINKONCE, decl);
732 /* For .text.foo we want to use .rodata.foo. */
733 else if (flag_function_sections && flag_data_sections
734 && strncmp (name, ".text.", 6) == 0)
736 size_t len = strlen (name) + 1;
737 char *rname = (char *) alloca (len + 2);
739 memcpy (rname, ".rodata", 7);
740 memcpy (rname + 7, name + 5, len - 5);
741 return get_section (rname, 0, decl);
745 return readonly_data_section;
748 /* Return the read-only data section associated with function DECL
749 for targets where that section should be always the single
750 readonly data section. */
752 section *
753 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
755 return readonly_data_section;
758 /* A subroutine of mergeable_string_section and mergeable_constant_section. */
760 static const char *
761 function_mergeable_rodata_prefix (void)
763 section *s = targetm.asm_out.function_rodata_section (current_function_decl);
764 if (SECTION_STYLE (s) == SECTION_NAMED)
765 return s->named.name;
766 else
767 return targetm.asm_out.mergeable_rodata_prefix;
770 /* Return the section to use for string merging. */
772 static section *
773 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
774 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
775 unsigned int flags ATTRIBUTE_UNUSED)
777 HOST_WIDE_INT len;
779 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
780 && TREE_CODE (decl) == STRING_CST
781 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
782 && align <= 256
783 && (len = int_size_in_bytes (TREE_TYPE (decl))) > 0
784 && TREE_STRING_LENGTH (decl) >= len)
786 machine_mode mode;
787 unsigned int modesize;
788 const char *str;
789 HOST_WIDE_INT i;
790 int j, unit;
791 const char *prefix = function_mergeable_rodata_prefix ();
792 char *name = (char *) alloca (strlen (prefix) + 30);
794 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
795 modesize = GET_MODE_BITSIZE (mode);
796 if (modesize >= 8 && modesize <= 256
797 && (modesize & (modesize - 1)) == 0)
799 if (align < modesize)
800 align = modesize;
802 str = TREE_STRING_POINTER (decl);
803 unit = GET_MODE_SIZE (mode);
805 /* Check for embedded NUL characters. */
806 for (i = 0; i < len; i += unit)
808 for (j = 0; j < unit; j++)
809 if (str[i + j] != '\0')
810 break;
811 if (j == unit)
812 break;
814 if (i == len - unit)
816 sprintf (name, "%s.str%d.%d", prefix,
817 modesize / 8, (int) (align / 8));
818 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
819 return get_section (name, flags, NULL);
824 return readonly_data_section;
827 /* Return the section to use for constant merging. */
829 section *
830 mergeable_constant_section (machine_mode mode ATTRIBUTE_UNUSED,
831 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
832 unsigned int flags ATTRIBUTE_UNUSED)
834 unsigned int modesize = GET_MODE_BITSIZE (mode);
836 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
837 && mode != VOIDmode
838 && mode != BLKmode
839 && modesize <= align
840 && align >= 8
841 && align <= 256
842 && (align & (align - 1)) == 0)
844 const char *prefix = function_mergeable_rodata_prefix ();
845 char *name = (char *) alloca (strlen (prefix) + 30);
847 sprintf (name, "%s.cst%d", prefix, (int) (align / 8));
848 flags |= (align / 8) | SECTION_MERGE;
849 return get_section (name, flags, NULL);
851 return readonly_data_section;
854 /* Given NAME, a putative register name, discard any customary prefixes. */
856 static const char *
857 strip_reg_name (const char *name)
859 #ifdef REGISTER_PREFIX
860 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
861 name += strlen (REGISTER_PREFIX);
862 #endif
863 if (name[0] == '%' || name[0] == '#')
864 name++;
865 return name;
868 /* The user has asked for a DECL to have a particular name. Set (or
869 change) it in such a way that we don't prefix an underscore to
870 it. */
871 void
872 set_user_assembler_name (tree decl, const char *name)
874 char *starred = (char *) alloca (strlen (name) + 2);
875 starred[0] = '*';
876 strcpy (starred + 1, name);
877 symtab->change_decl_assembler_name (decl, get_identifier (starred));
878 SET_DECL_RTL (decl, NULL_RTX);
881 /* Decode an `asm' spec for a declaration as a register name.
882 Return the register number, or -1 if nothing specified,
883 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
884 or -3 if ASMSPEC is `cc' and is not recognized,
885 or -4 if ASMSPEC is `memory' and is not recognized.
886 Accept an exact spelling or a decimal number.
887 Prefixes such as % are optional. */
890 decode_reg_name_and_count (const char *asmspec, int *pnregs)
892 /* Presume just one register is clobbered. */
893 *pnregs = 1;
895 if (asmspec != 0)
897 int i;
899 /* Get rid of confusing prefixes. */
900 asmspec = strip_reg_name (asmspec);
902 /* Allow a decimal number as a "register name". */
903 for (i = strlen (asmspec) - 1; i >= 0; i--)
904 if (! ISDIGIT (asmspec[i]))
905 break;
906 if (asmspec[0] != 0 && i < 0)
908 i = atoi (asmspec);
909 if (i < FIRST_PSEUDO_REGISTER && i >= 0 && reg_names[i][0])
910 return i;
911 else
912 return -2;
915 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
916 if (reg_names[i][0]
917 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
918 return i;
920 #ifdef OVERLAPPING_REGISTER_NAMES
922 static const struct
924 const char *const name;
925 const int number;
926 const int nregs;
927 } table[] = OVERLAPPING_REGISTER_NAMES;
929 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
930 if (table[i].name[0]
931 && ! strcmp (asmspec, table[i].name))
933 *pnregs = table[i].nregs;
934 return table[i].number;
937 #endif /* OVERLAPPING_REGISTER_NAMES */
939 #ifdef ADDITIONAL_REGISTER_NAMES
941 static const struct { const char *const name; const int number; } table[]
942 = ADDITIONAL_REGISTER_NAMES;
944 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
945 if (table[i].name[0]
946 && ! strcmp (asmspec, table[i].name)
947 && reg_names[table[i].number][0])
948 return table[i].number;
950 #endif /* ADDITIONAL_REGISTER_NAMES */
952 if (!strcmp (asmspec, "memory"))
953 return -4;
955 if (!strcmp (asmspec, "cc"))
956 return -3;
958 return -2;
961 return -1;
965 decode_reg_name (const char *name)
967 int count;
968 return decode_reg_name_and_count (name, &count);
972 /* Return true if DECL's initializer is suitable for a BSS section. */
974 bool
975 bss_initializer_p (const_tree decl)
977 return (DECL_INITIAL (decl) == NULL
978 /* In LTO we have no errors in program; error_mark_node is used
979 to mark offlined constructors. */
980 || (DECL_INITIAL (decl) == error_mark_node
981 && !in_lto_p)
982 || (flag_zero_initialized_in_bss
983 /* Leave constant zeroes in .rodata so they
984 can be shared. */
985 && !TREE_READONLY (decl)
986 && initializer_zerop (DECL_INITIAL (decl))));
989 /* Compute the alignment of variable specified by DECL.
990 DONT_OUTPUT_DATA is from assemble_variable. */
992 void
993 align_variable (tree decl, bool dont_output_data)
995 unsigned int align = DECL_ALIGN (decl);
997 /* In the case for initialing an array whose length isn't specified,
998 where we have not yet been able to do the layout,
999 figure out the proper alignment now. */
1000 if (dont_output_data && DECL_SIZE (decl) == 0
1001 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
1002 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
1004 /* Some object file formats have a maximum alignment which they support.
1005 In particular, a.out format supports a maximum alignment of 4. */
1006 if (align > MAX_OFILE_ALIGNMENT)
1008 error ("alignment of %q+D is greater than maximum object "
1009 "file alignment %d", decl,
1010 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
1011 align = MAX_OFILE_ALIGNMENT;
1014 if (! DECL_USER_ALIGN (decl))
1016 #ifdef DATA_ABI_ALIGNMENT
1017 unsigned int data_abi_align
1018 = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1019 /* For backwards compatibility, don't assume the ABI alignment for
1020 TLS variables. */
1021 if (! DECL_THREAD_LOCAL_P (decl) || data_abi_align <= BITS_PER_WORD)
1022 align = data_abi_align;
1023 #endif
1025 /* On some machines, it is good to increase alignment sometimes.
1026 But as DECL_ALIGN is used both for actually emitting the variable
1027 and for code accessing the variable as guaranteed alignment, we
1028 can only increase the alignment if it is a performance optimization
1029 if the references to it must bind to the current definition. */
1030 if (decl_binds_to_current_def_p (decl)
1031 && !DECL_VIRTUAL_P (decl))
1033 #ifdef DATA_ALIGNMENT
1034 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1035 /* Don't increase alignment too much for TLS variables - TLS space
1036 is too precious. */
1037 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1038 align = data_align;
1039 #endif
1040 if (DECL_INITIAL (decl) != 0
1041 /* In LTO we have no errors in program; error_mark_node is used
1042 to mark offlined constructors. */
1043 && (in_lto_p || DECL_INITIAL (decl) != error_mark_node))
1045 unsigned int const_align
1046 = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
1047 /* Don't increase alignment too much for TLS variables - TLS
1048 space is too precious. */
1049 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1050 align = const_align;
1055 /* Reset the alignment in case we have made it tighter, so we can benefit
1056 from it in get_pointer_alignment. */
1057 SET_DECL_ALIGN (decl, align);
1060 /* Return DECL_ALIGN (decl), possibly increased for optimization purposes
1061 beyond what align_variable returned. */
1063 static unsigned int
1064 get_variable_align (tree decl)
1066 unsigned int align = DECL_ALIGN (decl);
1068 /* For user aligned vars or static vars align_variable already did
1069 everything. */
1070 if (DECL_USER_ALIGN (decl) || !TREE_PUBLIC (decl))
1071 return align;
1073 #ifdef DATA_ABI_ALIGNMENT
1074 if (DECL_THREAD_LOCAL_P (decl))
1075 align = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1076 #endif
1078 /* For decls that bind to the current definition, align_variable
1079 did also everything, except for not assuming ABI required alignment
1080 of TLS variables. For other vars, increase the alignment here
1081 as an optimization. */
1082 if (!decl_binds_to_current_def_p (decl))
1084 /* On some machines, it is good to increase alignment sometimes. */
1085 #ifdef DATA_ALIGNMENT
1086 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1087 /* Don't increase alignment too much for TLS variables - TLS space
1088 is too precious. */
1089 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1090 align = data_align;
1091 #endif
1092 if (DECL_INITIAL (decl) != 0
1093 /* In LTO we have no errors in program; error_mark_node is used
1094 to mark offlined constructors. */
1095 && (in_lto_p || DECL_INITIAL (decl) != error_mark_node))
1097 unsigned int const_align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl),
1098 align);
1099 /* Don't increase alignment too much for TLS variables - TLS space
1100 is too precious. */
1101 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1102 align = const_align;
1106 return align;
1109 /* Return the section into which the given VAR_DECL or CONST_DECL
1110 should be placed. PREFER_NOSWITCH_P is true if a noswitch
1111 section should be used wherever possible. */
1113 section *
1114 get_variable_section (tree decl, bool prefer_noswitch_p)
1116 addr_space_t as = ADDR_SPACE_GENERIC;
1117 int reloc;
1118 varpool_node *vnode = varpool_node::get (decl);
1119 if (vnode)
1121 vnode = vnode->ultimate_alias_target ();
1122 decl = vnode->decl;
1125 if (TREE_TYPE (decl) != error_mark_node)
1126 as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1128 /* We need the constructor to figure out reloc flag. */
1129 if (vnode)
1130 vnode->get_constructor ();
1132 if (DECL_COMMON (decl))
1134 /* If the decl has been given an explicit section name, or it resides
1135 in a non-generic address space, then it isn't common, and shouldn't
1136 be handled as such. */
1137 gcc_assert (DECL_SECTION_NAME (decl) == NULL
1138 && ADDR_SPACE_GENERIC_P (as));
1139 if (DECL_THREAD_LOCAL_P (decl))
1140 return tls_comm_section;
1141 else if (TREE_PUBLIC (decl) && bss_initializer_p (decl))
1142 return comm_section;
1145 if (DECL_INITIAL (decl) == error_mark_node)
1146 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1147 else if (DECL_INITIAL (decl))
1148 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1149 else
1150 reloc = 0;
1152 resolve_unique_section (decl, reloc, flag_data_sections);
1153 if (IN_NAMED_SECTION (decl))
1155 section *sect = get_named_section (decl, NULL, reloc);
1157 if ((sect->common.flags & SECTION_BSS) && !bss_initializer_p (decl))
1159 error_at (DECL_SOURCE_LOCATION (decl),
1160 "only zero initializers are allowed in section %qs",
1161 sect->named.name);
1162 DECL_INITIAL (decl) = error_mark_node;
1164 return sect;
1167 if (ADDR_SPACE_GENERIC_P (as)
1168 && !DECL_THREAD_LOCAL_P (decl)
1169 && !(prefer_noswitch_p && targetm.have_switchable_bss_sections)
1170 && bss_initializer_p (decl))
1172 if (!TREE_PUBLIC (decl)
1173 && !((flag_sanitize & SANITIZE_ADDRESS)
1174 && asan_protect_global (decl)))
1175 return lcomm_section;
1176 if (bss_noswitch_section)
1177 return bss_noswitch_section;
1180 return targetm.asm_out.select_section (decl, reloc,
1181 get_variable_align (decl));
1184 /* Return the block into which object_block DECL should be placed. */
1186 static struct object_block *
1187 get_block_for_decl (tree decl)
1189 section *sect;
1191 if (VAR_P (decl))
1193 /* The object must be defined in this translation unit. */
1194 if (DECL_EXTERNAL (decl))
1195 return NULL;
1197 /* There's no point using object blocks for something that is
1198 isolated by definition. */
1199 if (DECL_COMDAT_GROUP (decl))
1200 return NULL;
1203 /* We can only calculate block offsets if the decl has a known
1204 constant size. */
1205 if (DECL_SIZE_UNIT (decl) == NULL)
1206 return NULL;
1207 if (!tree_fits_uhwi_p (DECL_SIZE_UNIT (decl)))
1208 return NULL;
1210 /* Find out which section should contain DECL. We cannot put it into
1211 an object block if it requires a standalone definition. */
1212 if (VAR_P (decl))
1213 align_variable (decl, 0);
1214 sect = get_variable_section (decl, true);
1215 if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
1216 return NULL;
1218 return get_block_for_section (sect);
1221 /* Make sure block symbol SYMBOL is in block BLOCK. */
1223 static void
1224 change_symbol_block (rtx symbol, struct object_block *block)
1226 if (block != SYMBOL_REF_BLOCK (symbol))
1228 gcc_assert (SYMBOL_REF_BLOCK_OFFSET (symbol) < 0);
1229 SYMBOL_REF_BLOCK (symbol) = block;
1233 /* Return true if it is possible to put DECL in an object_block. */
1235 static bool
1236 use_blocks_for_decl_p (tree decl)
1238 struct symtab_node *snode;
1240 /* Only data DECLs can be placed into object blocks. */
1241 if (!VAR_P (decl) && TREE_CODE (decl) != CONST_DECL)
1242 return false;
1244 /* Detect decls created by dw2_force_const_mem. Such decls are
1245 special because DECL_INITIAL doesn't specify the decl's true value.
1246 dw2_output_indirect_constants will instead call assemble_variable
1247 with dont_output_data set to 1 and then print the contents itself. */
1248 if (DECL_INITIAL (decl) == decl)
1249 return false;
1251 /* If this decl is an alias, then we don't want to emit a
1252 definition. */
1253 if (VAR_P (decl)
1254 && (snode = symtab_node::get (decl)) != NULL
1255 && snode->alias)
1256 return false;
1258 return targetm.use_blocks_for_decl_p (decl);
1261 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS
1262 until we find an identifier that is not itself a transparent alias.
1263 Modify the alias passed to it by reference (and all aliases on the
1264 way to the ultimate target), such that they do not have to be
1265 followed again, and return the ultimate target of the alias
1266 chain. */
1268 static inline tree
1269 ultimate_transparent_alias_target (tree *alias)
1271 tree target = *alias;
1273 if (IDENTIFIER_TRANSPARENT_ALIAS (target))
1275 gcc_assert (TREE_CHAIN (target));
1276 target = ultimate_transparent_alias_target (&TREE_CHAIN (target));
1277 gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target)
1278 && ! TREE_CHAIN (target));
1279 *alias = target;
1282 return target;
1285 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
1286 have static storage duration. In other words, it should not be an
1287 automatic variable, including PARM_DECLs.
1289 There is, however, one exception: this function handles variables
1290 explicitly placed in a particular register by the user.
1292 This is never called for PARM_DECL nodes. */
1294 void
1295 make_decl_rtl (tree decl)
1297 const char *name = 0;
1298 int reg_number;
1299 tree id;
1300 rtx x;
1302 /* Check that we are not being given an automatic variable. */
1303 gcc_assert (TREE_CODE (decl) != PARM_DECL
1304 && TREE_CODE (decl) != RESULT_DECL);
1306 /* A weak alias has TREE_PUBLIC set but not the other bits. */
1307 gcc_assert (!VAR_P (decl)
1308 || TREE_STATIC (decl)
1309 || TREE_PUBLIC (decl)
1310 || DECL_EXTERNAL (decl)
1311 || DECL_REGISTER (decl));
1313 /* And that we were not given a type or a label. */
1314 gcc_assert (TREE_CODE (decl) != TYPE_DECL
1315 && TREE_CODE (decl) != LABEL_DECL);
1317 /* For a duplicate declaration, we can be called twice on the
1318 same DECL node. Don't discard the RTL already made. */
1319 if (DECL_RTL_SET_P (decl))
1321 /* If the old RTL had the wrong mode, fix the mode. */
1322 x = DECL_RTL (decl);
1323 if (GET_MODE (x) != DECL_MODE (decl))
1324 SET_DECL_RTL (decl, adjust_address_nv (x, DECL_MODE (decl), 0));
1326 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1327 return;
1329 /* ??? Another way to do this would be to maintain a hashed
1330 table of such critters. Instead of adding stuff to a DECL
1331 to give certain attributes to it, we could use an external
1332 hash map from DECL to set of attributes. */
1334 /* Let the target reassign the RTL if it wants.
1335 This is necessary, for example, when one machine specific
1336 decl attribute overrides another. */
1337 targetm.encode_section_info (decl, DECL_RTL (decl), false);
1339 /* If the symbol has a SYMBOL_REF_BLOCK field, update it based
1340 on the new decl information. */
1341 if (MEM_P (x)
1342 && GET_CODE (XEXP (x, 0)) == SYMBOL_REF
1343 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (x, 0)))
1344 change_symbol_block (XEXP (x, 0), get_block_for_decl (decl));
1346 return;
1349 /* If this variable belongs to the global constant pool, retrieve the
1350 pre-computed RTL or recompute it in LTO mode. */
1351 if (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
1353 SET_DECL_RTL (decl, output_constant_def (DECL_INITIAL (decl), 1));
1354 return;
1357 id = DECL_ASSEMBLER_NAME (decl);
1358 if (TREE_CODE (decl) == FUNCTION_DECL
1359 && cgraph_node::get (decl)
1360 && cgraph_node::get (decl)->instrumentation_clone)
1361 ultimate_transparent_alias_target (&id);
1362 name = IDENTIFIER_POINTER (id);
1364 if (name[0] != '*' && TREE_CODE (decl) != FUNCTION_DECL
1365 && DECL_REGISTER (decl))
1367 error ("register name not specified for %q+D", decl);
1369 else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1371 const char *asmspec = name+1;
1372 machine_mode mode = DECL_MODE (decl);
1373 reg_number = decode_reg_name (asmspec);
1374 /* First detect errors in declaring global registers. */
1375 if (reg_number == -1)
1376 error ("register name not specified for %q+D", decl);
1377 else if (reg_number < 0)
1378 error ("invalid register name for %q+D", decl);
1379 else if (mode == BLKmode)
1380 error ("data type of %q+D isn%'t suitable for a register",
1381 decl);
1382 else if (!in_hard_reg_set_p (accessible_reg_set, mode, reg_number))
1383 error ("the register specified for %q+D cannot be accessed"
1384 " by the current target", decl);
1385 else if (!in_hard_reg_set_p (operand_reg_set, mode, reg_number))
1386 error ("the register specified for %q+D is not general enough"
1387 " to be used as a register variable", decl);
1388 else if (!HARD_REGNO_MODE_OK (reg_number, mode))
1389 error ("register specified for %q+D isn%'t suitable for data type",
1390 decl);
1391 /* Now handle properly declared static register variables. */
1392 else
1394 int nregs;
1396 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
1398 DECL_INITIAL (decl) = 0;
1399 error ("global register variable has initial value");
1401 if (TREE_THIS_VOLATILE (decl))
1402 warning (OPT_Wvolatile_register_var,
1403 "optimization may eliminate reads and/or "
1404 "writes to register variables");
1406 /* If the user specified one of the eliminables registers here,
1407 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
1408 confused with that register and be eliminated. This usage is
1409 somewhat suspect... */
1411 SET_DECL_RTL (decl, gen_raw_REG (mode, reg_number));
1412 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
1413 REG_USERVAR_P (DECL_RTL (decl)) = 1;
1415 if (TREE_STATIC (decl))
1417 /* Make this register global, so not usable for anything
1418 else. */
1419 #ifdef ASM_DECLARE_REGISTER_GLOBAL
1420 name = IDENTIFIER_POINTER (DECL_NAME (decl));
1421 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
1422 #endif
1423 nregs = hard_regno_nregs[reg_number][mode];
1424 while (nregs > 0)
1425 globalize_reg (decl, reg_number + --nregs);
1428 /* As a register variable, it has no section. */
1429 return;
1431 /* Avoid internal errors from invalid register
1432 specifications. */
1433 SET_DECL_ASSEMBLER_NAME (decl, NULL_TREE);
1434 DECL_HARD_REGISTER (decl) = 0;
1435 /* Also avoid SSA inconsistencies by pretending this is an external
1436 decl now. */
1437 DECL_EXTERNAL (decl) = 1;
1438 return;
1440 /* Now handle ordinary static variables and functions (in memory).
1441 Also handle vars declared register invalidly. */
1442 else if (name[0] == '*')
1444 #ifdef REGISTER_PREFIX
1445 if (strlen (REGISTER_PREFIX) != 0)
1447 reg_number = decode_reg_name (name);
1448 if (reg_number >= 0 || reg_number == -3)
1449 error ("register name given for non-register variable %q+D", decl);
1451 #endif
1454 /* Specifying a section attribute on a variable forces it into a
1455 non-.bss section, and thus it cannot be common. */
1456 /* FIXME: In general this code should not be necessary because
1457 visibility pass is doing the same work. But notice_global_symbol
1458 is called early and it needs to make DECL_RTL to get the name.
1459 we take care of recomputing the DECL_RTL after visibility is changed. */
1460 if (VAR_P (decl)
1461 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl))
1462 && DECL_SECTION_NAME (decl) != NULL
1463 && DECL_INITIAL (decl) == NULL_TREE
1464 && DECL_COMMON (decl))
1465 DECL_COMMON (decl) = 0;
1467 /* Variables can't be both common and weak. */
1468 if (VAR_P (decl) && DECL_WEAK (decl))
1469 DECL_COMMON (decl) = 0;
1471 if (use_object_blocks_p () && use_blocks_for_decl_p (decl))
1472 x = create_block_symbol (name, get_block_for_decl (decl), -1);
1473 else
1475 machine_mode address_mode = Pmode;
1476 if (TREE_TYPE (decl) != error_mark_node)
1478 addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1479 address_mode = targetm.addr_space.address_mode (as);
1481 x = gen_rtx_SYMBOL_REF (address_mode, name);
1483 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
1484 SET_SYMBOL_REF_DECL (x, decl);
1486 x = gen_rtx_MEM (DECL_MODE (decl), x);
1487 if (TREE_CODE (decl) != FUNCTION_DECL)
1488 set_mem_attributes (x, decl, 1);
1489 SET_DECL_RTL (decl, x);
1491 /* Optionally set flags or add text to the name to record information
1492 such as that it is a function name.
1493 If the name is changed, the macro ASM_OUTPUT_LABELREF
1494 will have to know how to strip this information. */
1495 targetm.encode_section_info (decl, DECL_RTL (decl), true);
1498 /* Like make_decl_rtl, but inhibit creation of new alias sets when
1499 calling make_decl_rtl. Also, reset DECL_RTL before returning the
1500 rtl. */
1503 make_decl_rtl_for_debug (tree decl)
1505 unsigned int save_aliasing_flag;
1506 rtx rtl;
1508 if (DECL_RTL_SET_P (decl))
1509 return DECL_RTL (decl);
1511 /* Kludge alert! Somewhere down the call chain, make_decl_rtl will
1512 call new_alias_set. If running with -fcompare-debug, sometimes
1513 we do not want to create alias sets that will throw the alias
1514 numbers off in the comparison dumps. So... clearing
1515 flag_strict_aliasing will keep new_alias_set() from creating a
1516 new set. */
1517 save_aliasing_flag = flag_strict_aliasing;
1518 flag_strict_aliasing = 0;
1520 rtl = DECL_RTL (decl);
1521 /* Reset DECL_RTL back, as various parts of the compiler expects
1522 DECL_RTL set meaning it is actually going to be output. */
1523 SET_DECL_RTL (decl, NULL);
1525 flag_strict_aliasing = save_aliasing_flag;
1526 return rtl;
1529 /* Output a string of literal assembler code
1530 for an `asm' keyword used between functions. */
1532 void
1533 assemble_asm (tree string)
1535 const char *p;
1536 app_enable ();
1538 if (TREE_CODE (string) == ADDR_EXPR)
1539 string = TREE_OPERAND (string, 0);
1541 p = TREE_STRING_POINTER (string);
1542 fprintf (asm_out_file, "%s%s\n", p[0] == '\t' ? "" : "\t", p);
1545 /* Write the address of the entity given by SYMBOL to SEC. */
1546 void
1547 assemble_addr_to_section (rtx symbol, section *sec)
1549 switch_to_section (sec);
1550 assemble_align (POINTER_SIZE);
1551 assemble_integer (symbol, POINTER_SIZE_UNITS, POINTER_SIZE, 1);
1554 /* Return the numbered .ctors.N (if CONSTRUCTOR_P) or .dtors.N (if
1555 not) section for PRIORITY. */
1556 section *
1557 get_cdtor_priority_section (int priority, bool constructor_p)
1559 /* Buffer conservatively large enough for the full range of a 32-bit
1560 int plus the text below. */
1561 char buf[18];
1563 /* ??? This only works reliably with the GNU linker. */
1564 sprintf (buf, "%s.%.5u",
1565 constructor_p ? ".ctors" : ".dtors",
1566 /* Invert the numbering so the linker puts us in the proper
1567 order; constructors are run from right to left, and the
1568 linker sorts in increasing order. */
1569 MAX_INIT_PRIORITY - priority);
1570 return get_section (buf, SECTION_WRITE, NULL);
1573 void
1574 default_named_section_asm_out_destructor (rtx symbol, int priority)
1576 section *sec;
1578 if (priority != DEFAULT_INIT_PRIORITY)
1579 sec = get_cdtor_priority_section (priority,
1580 /*constructor_p=*/false);
1581 else
1582 sec = get_section (".dtors", SECTION_WRITE, NULL);
1584 assemble_addr_to_section (symbol, sec);
1587 #ifdef DTORS_SECTION_ASM_OP
1588 void
1589 default_dtor_section_asm_out_destructor (rtx symbol,
1590 int priority ATTRIBUTE_UNUSED)
1592 assemble_addr_to_section (symbol, dtors_section);
1594 #endif
1596 void
1597 default_named_section_asm_out_constructor (rtx symbol, int priority)
1599 section *sec;
1601 if (priority != DEFAULT_INIT_PRIORITY)
1602 sec = get_cdtor_priority_section (priority,
1603 /*constructor_p=*/true);
1604 else
1605 sec = get_section (".ctors", SECTION_WRITE, NULL);
1607 assemble_addr_to_section (symbol, sec);
1610 #ifdef CTORS_SECTION_ASM_OP
1611 void
1612 default_ctor_section_asm_out_constructor (rtx symbol,
1613 int priority ATTRIBUTE_UNUSED)
1615 assemble_addr_to_section (symbol, ctors_section);
1617 #endif
1619 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1620 a nonzero value if the constant pool should be output before the
1621 start of the function, or a zero value if the pool should output
1622 after the end of the function. The default is to put it before the
1623 start. */
1625 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1626 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1627 #endif
1629 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1630 to be output to assembler.
1631 Set first_global_object_name and weak_global_object_name as appropriate. */
1633 void
1634 notice_global_symbol (tree decl)
1636 const char **t = &first_global_object_name;
1638 if (first_global_object_name
1639 || !TREE_PUBLIC (decl)
1640 || DECL_EXTERNAL (decl)
1641 || !DECL_NAME (decl)
1642 || (VAR_P (decl) && DECL_HARD_REGISTER (decl))
1643 || (TREE_CODE (decl) != FUNCTION_DECL
1644 && (!VAR_P (decl)
1645 || (DECL_COMMON (decl)
1646 && (DECL_INITIAL (decl) == 0
1647 || DECL_INITIAL (decl) == error_mark_node)))))
1648 return;
1650 /* We win when global object is found, but it is useful to know about weak
1651 symbol as well so we can produce nicer unique names. */
1652 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl) || flag_shlib)
1653 t = &weak_global_object_name;
1655 if (!*t)
1657 tree id = DECL_ASSEMBLER_NAME (decl);
1658 ultimate_transparent_alias_target (&id);
1659 *t = ggc_strdup (targetm.strip_name_encoding (IDENTIFIER_POINTER (id)));
1663 /* If not using flag_reorder_blocks_and_partition, decide early whether the
1664 current function goes into the cold section, so that targets can use
1665 current_function_section during RTL expansion. DECL describes the
1666 function. */
1668 void
1669 decide_function_section (tree decl)
1671 first_function_block_is_cold = false;
1673 if (flag_reorder_blocks_and_partition)
1674 /* We will decide in assemble_start_function. */
1675 return;
1677 if (DECL_SECTION_NAME (decl))
1679 struct cgraph_node *node = cgraph_node::get (current_function_decl);
1680 /* Calls to function_section rely on first_function_block_is_cold
1681 being accurate. */
1682 first_function_block_is_cold = (node
1683 && node->frequency
1684 == NODE_FREQUENCY_UNLIKELY_EXECUTED);
1687 in_cold_section_p = first_function_block_is_cold;
1690 /* Get the function's name, as described by its RTL. This may be
1691 different from the DECL_NAME name used in the source file. */
1692 const char *
1693 get_fnname_from_decl (tree decl)
1695 rtx x = DECL_RTL (decl);
1696 gcc_assert (MEM_P (x));
1697 x = XEXP (x, 0);
1698 gcc_assert (GET_CODE (x) == SYMBOL_REF);
1699 return XSTR (x, 0);
1702 /* Output assembler code for the constant pool of a function and associated
1703 with defining the name of the function. DECL describes the function.
1704 NAME is the function's name. For the constant pool, we use the current
1705 constant pool data. */
1707 void
1708 assemble_start_function (tree decl, const char *fnname)
1710 int align;
1711 char tmp_label[100];
1712 bool hot_label_written = false;
1714 if (flag_reorder_blocks_and_partition)
1716 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTB", const_labelno);
1717 crtl->subsections.hot_section_label = ggc_strdup (tmp_label);
1718 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDB", const_labelno);
1719 crtl->subsections.cold_section_label = ggc_strdup (tmp_label);
1720 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTE", const_labelno);
1721 crtl->subsections.hot_section_end_label = ggc_strdup (tmp_label);
1722 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDE", const_labelno);
1723 crtl->subsections.cold_section_end_label = ggc_strdup (tmp_label);
1724 const_labelno++;
1725 cold_function_name = NULL_TREE;
1727 else
1729 crtl->subsections.hot_section_label = NULL;
1730 crtl->subsections.cold_section_label = NULL;
1731 crtl->subsections.hot_section_end_label = NULL;
1732 crtl->subsections.cold_section_end_label = NULL;
1735 /* The following code does not need preprocessing in the assembler. */
1737 app_disable ();
1739 if (CONSTANT_POOL_BEFORE_FUNCTION)
1740 output_constant_pool (fnname, decl);
1742 align = symtab_node::get (decl)->definition_alignment ();
1744 /* Make sure the not and cold text (code) sections are properly
1745 aligned. This is necessary here in the case where the function
1746 has both hot and cold sections, because we don't want to re-set
1747 the alignment when the section switch happens mid-function. */
1749 if (flag_reorder_blocks_and_partition)
1751 first_function_block_is_cold = false;
1753 switch_to_section (unlikely_text_section ());
1754 assemble_align (align);
1755 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_label);
1757 /* When the function starts with a cold section, we need to explicitly
1758 align the hot section and write out the hot section label.
1759 But if the current function is a thunk, we do not have a CFG. */
1760 if (!cfun->is_thunk
1761 && BB_PARTITION (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) == BB_COLD_PARTITION)
1763 switch_to_section (text_section);
1764 assemble_align (align);
1765 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1766 hot_label_written = true;
1767 first_function_block_is_cold = true;
1769 in_cold_section_p = first_function_block_is_cold;
1773 /* Switch to the correct text section for the start of the function. */
1775 switch_to_section (function_section (decl));
1776 if (flag_reorder_blocks_and_partition
1777 && !hot_label_written)
1778 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1780 /* Tell assembler to move to target machine's alignment for functions. */
1781 align = floor_log2 (align / BITS_PER_UNIT);
1782 if (align > 0)
1784 ASM_OUTPUT_ALIGN (asm_out_file, align);
1787 /* Handle a user-specified function alignment.
1788 Note that we still need to align to DECL_ALIGN, as above,
1789 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1790 if (! DECL_USER_ALIGN (decl)
1791 && align_functions_log > align
1792 && optimize_function_for_speed_p (cfun))
1794 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1795 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1796 align_functions_log, align_functions - 1);
1797 #else
1798 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1799 #endif
1802 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1803 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1804 #endif
1806 if (!DECL_IGNORED_P (decl))
1807 (*debug_hooks->begin_function) (decl);
1809 /* Make function name accessible from other files, if appropriate. */
1811 if (TREE_PUBLIC (decl)
1812 || (cgraph_node::get (decl)->instrumentation_clone
1813 && cgraph_node::get (decl)->instrumented_version
1814 && TREE_PUBLIC (cgraph_node::get (decl)->instrumented_version->decl)))
1816 notice_global_symbol (decl);
1818 globalize_decl (decl);
1820 maybe_assemble_visibility (decl);
1823 if (DECL_PRESERVE_P (decl))
1824 targetm.asm_out.mark_decl_preserved (fnname);
1826 /* Do any machine/system dependent processing of the function name. */
1827 #ifdef ASM_DECLARE_FUNCTION_NAME
1828 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1829 #else
1830 /* Standard thing is just output label for the function. */
1831 ASM_OUTPUT_FUNCTION_LABEL (asm_out_file, fnname, current_function_decl);
1832 #endif /* ASM_DECLARE_FUNCTION_NAME */
1834 if (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (decl)))
1835 saw_no_split_stack = true;
1838 /* Output assembler code associated with defining the size of the
1839 function. DECL describes the function. NAME is the function's name. */
1841 void
1842 assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED)
1844 #ifdef ASM_DECLARE_FUNCTION_SIZE
1845 /* We could have switched section in the middle of the function. */
1846 if (flag_reorder_blocks_and_partition)
1847 switch_to_section (function_section (decl));
1848 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1849 #endif
1850 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1852 output_constant_pool (fnname, decl);
1853 switch_to_section (function_section (decl)); /* need to switch back */
1855 /* Output labels for end of hot/cold text sections (to be used by
1856 debug info.) */
1857 if (flag_reorder_blocks_and_partition)
1859 section *save_text_section;
1861 save_text_section = in_section;
1862 switch_to_section (unlikely_text_section ());
1863 #ifdef ASM_DECLARE_COLD_FUNCTION_SIZE
1864 if (cold_function_name != NULL_TREE)
1865 ASM_DECLARE_COLD_FUNCTION_SIZE (asm_out_file,
1866 IDENTIFIER_POINTER (cold_function_name),
1867 decl);
1868 #endif
1869 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label);
1870 if (first_function_block_is_cold)
1871 switch_to_section (text_section);
1872 else
1873 switch_to_section (function_section (decl));
1874 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label);
1875 switch_to_section (save_text_section);
1879 /* Assemble code to leave SIZE bytes of zeros. */
1881 void
1882 assemble_zeros (unsigned HOST_WIDE_INT size)
1884 /* Do no output if -fsyntax-only. */
1885 if (flag_syntax_only)
1886 return;
1888 #ifdef ASM_NO_SKIP_IN_TEXT
1889 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1890 so we must output 0s explicitly in the text section. */
1891 if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0)
1893 unsigned HOST_WIDE_INT i;
1894 for (i = 0; i < size; i++)
1895 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1897 else
1898 #endif
1899 if (size > 0)
1900 ASM_OUTPUT_SKIP (asm_out_file, size);
1903 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1905 void
1906 assemble_align (int align)
1908 if (align > BITS_PER_UNIT)
1910 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1914 /* Assemble a string constant with the specified C string as contents. */
1916 void
1917 assemble_string (const char *p, int size)
1919 int pos = 0;
1920 int maximum = 2000;
1922 /* If the string is very long, split it up. */
1924 while (pos < size)
1926 int thissize = size - pos;
1927 if (thissize > maximum)
1928 thissize = maximum;
1930 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1932 pos += thissize;
1933 p += thissize;
1938 /* A noswitch_section_callback for lcomm_section. */
1940 static bool
1941 emit_local (tree decl ATTRIBUTE_UNUSED,
1942 const char *name ATTRIBUTE_UNUSED,
1943 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1944 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1946 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1947 unsigned int align = symtab_node::get (decl)->definition_alignment ();
1948 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name,
1949 size, align);
1950 return true;
1951 #elif defined ASM_OUTPUT_ALIGNED_LOCAL
1952 unsigned int align = symtab_node::get (decl)->definition_alignment ();
1953 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, align);
1954 return true;
1955 #else
1956 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1957 return false;
1958 #endif
1961 /* A noswitch_section_callback for bss_noswitch_section. */
1963 #if defined ASM_OUTPUT_ALIGNED_BSS
1964 static bool
1965 emit_bss (tree decl ATTRIBUTE_UNUSED,
1966 const char *name ATTRIBUTE_UNUSED,
1967 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1968 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1970 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size,
1971 get_variable_align (decl));
1972 return true;
1974 #endif
1976 /* A noswitch_section_callback for comm_section. */
1978 static bool
1979 emit_common (tree decl ATTRIBUTE_UNUSED,
1980 const char *name ATTRIBUTE_UNUSED,
1981 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1982 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1984 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1985 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name,
1986 size, get_variable_align (decl));
1987 return true;
1988 #elif defined ASM_OUTPUT_ALIGNED_COMMON
1989 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size,
1990 get_variable_align (decl));
1991 return true;
1992 #else
1993 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
1994 return false;
1995 #endif
1998 /* A noswitch_section_callback for tls_comm_section. */
2000 static bool
2001 emit_tls_common (tree decl ATTRIBUTE_UNUSED,
2002 const char *name ATTRIBUTE_UNUSED,
2003 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2004 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2006 #ifdef ASM_OUTPUT_TLS_COMMON
2007 ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size);
2008 return true;
2009 #else
2010 sorry ("thread-local COMMON data not implemented");
2011 return true;
2012 #endif
2015 /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT.
2016 NAME is the name of DECL's SYMBOL_REF. */
2018 static void
2019 assemble_noswitch_variable (tree decl, const char *name, section *sect,
2020 unsigned int align)
2022 unsigned HOST_WIDE_INT size, rounded;
2024 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2025 rounded = size;
2027 if ((flag_sanitize & SANITIZE_ADDRESS) && asan_protect_global (decl))
2028 size += asan_red_zone_size (size);
2030 /* Don't allocate zero bytes of common,
2031 since that means "undefined external" in the linker. */
2032 if (size == 0)
2033 rounded = 1;
2035 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2036 so that each uninitialized object starts on such a boundary. */
2037 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
2038 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2039 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2041 if (!sect->noswitch.callback (decl, name, size, rounded)
2042 && (unsigned HOST_WIDE_INT) (align / BITS_PER_UNIT) > rounded)
2043 error ("requested alignment for %q+D is greater than "
2044 "implemented alignment of %wu", decl, rounded);
2047 /* A subroutine of assemble_variable. Output the label and contents of
2048 DECL, whose address is a SYMBOL_REF with name NAME. DONT_OUTPUT_DATA
2049 is as for assemble_variable. */
2051 static void
2052 assemble_variable_contents (tree decl, const char *name,
2053 bool dont_output_data)
2055 /* Do any machine/system dependent processing of the object. */
2056 #ifdef ASM_DECLARE_OBJECT_NAME
2057 last_assemble_variable_decl = decl;
2058 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
2059 #else
2060 /* Standard thing is just output label for the object. */
2061 ASM_OUTPUT_LABEL (asm_out_file, name);
2062 #endif /* ASM_DECLARE_OBJECT_NAME */
2064 if (!dont_output_data)
2066 /* Caller is supposed to use varpool_get_constructor when it wants
2067 to output the body. */
2068 gcc_assert (!in_lto_p || DECL_INITIAL (decl) != error_mark_node);
2069 if (DECL_INITIAL (decl)
2070 && DECL_INITIAL (decl) != error_mark_node
2071 && !initializer_zerop (DECL_INITIAL (decl)))
2072 /* Output the actual data. */
2073 output_constant (DECL_INITIAL (decl),
2074 tree_to_uhwi (DECL_SIZE_UNIT (decl)),
2075 get_variable_align (decl),
2076 false);
2077 else
2078 /* Leave space for it. */
2079 assemble_zeros (tree_to_uhwi (DECL_SIZE_UNIT (decl)));
2080 targetm.asm_out.decl_end ();
2084 /* Write out assembly for the variable DECL, which is not defined in
2085 the current translation unit. */
2086 void
2087 assemble_undefined_decl (tree decl)
2089 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
2090 targetm.asm_out.assemble_undefined_decl (asm_out_file, name, decl);
2093 /* Assemble everything that is needed for a variable or function declaration.
2094 Not used for automatic variables, and not used for function definitions.
2095 Should not be called for variables of incomplete structure type.
2097 TOP_LEVEL is nonzero if this variable has file scope.
2098 AT_END is nonzero if this is the special handling, at end of compilation,
2099 to define things that have had only tentative definitions.
2100 DONT_OUTPUT_DATA if nonzero means don't actually output the
2101 initial value (that will be done by the caller). */
2103 void
2104 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
2105 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
2107 const char *name;
2108 rtx decl_rtl, symbol;
2109 section *sect;
2110 unsigned int align;
2111 bool asan_protected = false;
2113 /* This function is supposed to handle VARIABLES. Ensure we have one. */
2114 gcc_assert (VAR_P (decl));
2116 /* Emulated TLS had better not get this far. */
2117 gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl));
2119 last_assemble_variable_decl = 0;
2121 /* Normally no need to say anything here for external references,
2122 since assemble_external is called by the language-specific code
2123 when a declaration is first seen. */
2125 if (DECL_EXTERNAL (decl))
2126 return;
2128 /* Do nothing for global register variables. */
2129 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
2131 TREE_ASM_WRITTEN (decl) = 1;
2132 return;
2135 /* If type was incomplete when the variable was declared,
2136 see if it is complete now. */
2138 if (DECL_SIZE (decl) == 0)
2139 layout_decl (decl, 0);
2141 /* Still incomplete => don't allocate it; treat the tentative defn
2142 (which is what it must have been) as an `extern' reference. */
2144 if (!dont_output_data && DECL_SIZE (decl) == 0)
2146 error ("storage size of %q+D isn%'t known", decl);
2147 TREE_ASM_WRITTEN (decl) = 1;
2148 return;
2151 /* The first declaration of a variable that comes through this function
2152 decides whether it is global (in C, has external linkage)
2153 or local (in C, has internal linkage). So do nothing more
2154 if this function has already run. */
2156 if (TREE_ASM_WRITTEN (decl))
2157 return;
2159 /* Make sure targetm.encode_section_info is invoked before we set
2160 ASM_WRITTEN. */
2161 decl_rtl = DECL_RTL (decl);
2163 TREE_ASM_WRITTEN (decl) = 1;
2165 /* Do no output if -fsyntax-only. */
2166 if (flag_syntax_only)
2167 return;
2169 if (! dont_output_data
2170 && ! valid_constant_size_p (DECL_SIZE_UNIT (decl)))
2172 error ("size of variable %q+D is too large", decl);
2173 return;
2176 gcc_assert (MEM_P (decl_rtl));
2177 gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF);
2178 symbol = XEXP (decl_rtl, 0);
2180 /* If this symbol belongs to the tree constant pool, output the constant
2181 if it hasn't already been written. */
2182 if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
2184 tree decl = SYMBOL_REF_DECL (symbol);
2185 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
2186 output_constant_def_contents (symbol);
2187 return;
2190 app_disable ();
2192 name = XSTR (symbol, 0);
2193 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
2194 notice_global_symbol (decl);
2196 /* Compute the alignment of this data. */
2198 align_variable (decl, dont_output_data);
2200 if ((flag_sanitize & SANITIZE_ADDRESS)
2201 && asan_protect_global (decl))
2203 asan_protected = true;
2204 SET_DECL_ALIGN (decl, MAX (DECL_ALIGN (decl),
2205 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT));
2208 set_mem_align (decl_rtl, DECL_ALIGN (decl));
2210 align = get_variable_align (decl);
2212 if (TREE_PUBLIC (decl))
2213 maybe_assemble_visibility (decl);
2215 if (DECL_PRESERVE_P (decl))
2216 targetm.asm_out.mark_decl_preserved (name);
2218 /* First make the assembler name(s) global if appropriate. */
2219 sect = get_variable_section (decl, false);
2220 if (TREE_PUBLIC (decl)
2221 && (sect->common.flags & SECTION_COMMON) == 0)
2222 globalize_decl (decl);
2224 /* Output any data that we will need to use the address of. */
2225 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
2226 output_addressed_constants (DECL_INITIAL (decl));
2228 /* dbxout.c needs to know this. */
2229 if (sect && (sect->common.flags & SECTION_CODE) != 0)
2230 DECL_IN_TEXT_SECTION (decl) = 1;
2232 /* If the decl is part of an object_block, make sure that the decl
2233 has been positioned within its block, but do not write out its
2234 definition yet. output_object_blocks will do that later. */
2235 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
2237 gcc_assert (!dont_output_data);
2238 place_block_symbol (symbol);
2240 else if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
2241 assemble_noswitch_variable (decl, name, sect, align);
2242 else
2244 /* Special-case handling of vtv comdat sections. */
2245 if (sect->named.name
2246 && (strcmp (sect->named.name, ".vtable_map_vars") == 0))
2247 handle_vtv_comdat_section (sect, decl);
2248 else
2249 switch_to_section (sect);
2250 if (align > BITS_PER_UNIT)
2251 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2252 assemble_variable_contents (decl, name, dont_output_data);
2253 if (asan_protected)
2255 unsigned HOST_WIDE_INT int size
2256 = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2257 assemble_zeros (asan_red_zone_size (size));
2263 /* Given a function declaration (FN_DECL), this function assembles the
2264 function into the .preinit_array section. */
2266 void
2267 assemble_vtv_preinit_initializer (tree fn_decl)
2269 section *sect;
2270 unsigned flags = SECTION_WRITE;
2271 rtx symbol = XEXP (DECL_RTL (fn_decl), 0);
2273 flags |= SECTION_NOTYPE;
2274 sect = get_section (".preinit_array", flags, fn_decl);
2275 switch_to_section (sect);
2276 assemble_addr_to_section (symbol, sect);
2279 /* Return 1 if type TYPE contains any pointers. */
2281 static int
2282 contains_pointers_p (tree type)
2284 switch (TREE_CODE (type))
2286 case POINTER_TYPE:
2287 case REFERENCE_TYPE:
2288 /* I'm not sure whether OFFSET_TYPE needs this treatment,
2289 so I'll play safe and return 1. */
2290 case OFFSET_TYPE:
2291 return 1;
2293 case RECORD_TYPE:
2294 case UNION_TYPE:
2295 case QUAL_UNION_TYPE:
2297 tree fields;
2298 /* For a type that has fields, see if the fields have pointers. */
2299 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2300 if (TREE_CODE (fields) == FIELD_DECL
2301 && contains_pointers_p (TREE_TYPE (fields)))
2302 return 1;
2303 return 0;
2306 case ARRAY_TYPE:
2307 /* An array type contains pointers if its element type does. */
2308 return contains_pointers_p (TREE_TYPE (type));
2310 default:
2311 return 0;
2315 /* We delay assemble_external processing until
2316 the compilation unit is finalized. This is the best we can do for
2317 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2318 it all the way to final. See PR 17982 for further discussion. */
2319 static GTY(()) tree pending_assemble_externals;
2321 #ifdef ASM_OUTPUT_EXTERNAL
2322 /* Some targets delay some output to final using TARGET_ASM_FILE_END.
2323 As a result, assemble_external can be called after the list of externals
2324 is processed and the pointer set destroyed. */
2325 static bool pending_assemble_externals_processed;
2327 /* Avoid O(external_decls**2) lookups in the pending_assemble_externals
2328 TREE_LIST in assemble_external. */
2329 static hash_set<tree> *pending_assemble_externals_set;
2331 /* True if DECL is a function decl for which no out-of-line copy exists.
2332 It is assumed that DECL's assembler name has been set. */
2334 static bool
2335 incorporeal_function_p (tree decl)
2337 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
2339 const char *name;
2341 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2342 && (DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA
2343 || DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA_WITH_ALIGN))
2344 return true;
2346 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2347 /* Atomic or sync builtins which have survived this far will be
2348 resolved externally and therefore are not incorporeal. */
2349 if (strncmp (name, "__builtin_", 10) == 0)
2350 return true;
2352 return false;
2355 /* Actually do the tests to determine if this is necessary, and invoke
2356 ASM_OUTPUT_EXTERNAL. */
2357 static void
2358 assemble_external_real (tree decl)
2360 rtx rtl = DECL_RTL (decl);
2362 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2363 && !SYMBOL_REF_USED (XEXP (rtl, 0))
2364 && !incorporeal_function_p (decl))
2366 /* Some systems do require some output. */
2367 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2368 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2371 #endif
2373 void
2374 process_pending_assemble_externals (void)
2376 #ifdef ASM_OUTPUT_EXTERNAL
2377 tree list;
2378 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2379 assemble_external_real (TREE_VALUE (list));
2381 pending_assemble_externals = 0;
2382 pending_assemble_externals_processed = true;
2383 delete pending_assemble_externals_set;
2384 #endif
2387 /* This TREE_LIST contains any weak symbol declarations waiting
2388 to be emitted. */
2389 static GTY(()) tree weak_decls;
2391 /* Output something to declare an external symbol to the assembler,
2392 and qualifiers such as weakness. (Most assemblers don't need
2393 extern declaration, so we normally output nothing.) Do nothing if
2394 DECL is not external. */
2396 void
2397 assemble_external (tree decl ATTRIBUTE_UNUSED)
2399 /* Make sure that the ASM_OUT_FILE is open.
2400 If it's not, we should not be calling this function. */
2401 gcc_assert (asm_out_file);
2403 /* In a perfect world, the following condition would be true.
2404 Sadly, the Java and Go front ends emit assembly *from the front end*,
2405 bypassing the call graph. See PR52739. Fix before GCC 4.8. */
2406 #if 0
2407 /* This function should only be called if we are expanding, or have
2408 expanded, to RTL.
2409 Ideally, only final.c would be calling this function, but it is
2410 not clear whether that would break things somehow. See PR 17982
2411 for further discussion. */
2412 gcc_assert (state == EXPANSION
2413 || state == FINISHED);
2414 #endif
2416 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2417 return;
2419 /* We want to output annotation for weak and external symbols at
2420 very last to check if they are references or not. */
2422 if (TARGET_SUPPORTS_WEAK
2423 && DECL_WEAK (decl)
2424 /* TREE_STATIC is a weird and abused creature which is not
2425 generally the right test for whether an entity has been
2426 locally emitted, inlined or otherwise not-really-extern, but
2427 for declarations that can be weak, it happens to be
2428 match. */
2429 && !TREE_STATIC (decl)
2430 && lookup_attribute ("weak", DECL_ATTRIBUTES (decl))
2431 && value_member (decl, weak_decls) == NULL_TREE)
2432 weak_decls = tree_cons (NULL, decl, weak_decls);
2434 #ifdef ASM_OUTPUT_EXTERNAL
2435 if (pending_assemble_externals_processed)
2437 assemble_external_real (decl);
2438 return;
2441 if (! pending_assemble_externals_set->add (decl))
2442 pending_assemble_externals = tree_cons (NULL, decl,
2443 pending_assemble_externals);
2444 #endif
2447 /* Similar, for calling a library function FUN. */
2449 void
2450 assemble_external_libcall (rtx fun)
2452 /* Declare library function name external when first used, if nec. */
2453 if (! SYMBOL_REF_USED (fun))
2455 SYMBOL_REF_USED (fun) = 1;
2456 targetm.asm_out.external_libcall (fun);
2460 /* Assemble a label named NAME. */
2462 void
2463 assemble_label (FILE *file, const char *name)
2465 ASM_OUTPUT_LABEL (file, name);
2468 /* Set the symbol_referenced flag for ID. */
2469 void
2470 mark_referenced (tree id)
2472 TREE_SYMBOL_REFERENCED (id) = 1;
2475 /* Set the symbol_referenced flag for DECL and notify callgraph. */
2476 void
2477 mark_decl_referenced (tree decl)
2479 if (TREE_CODE (decl) == FUNCTION_DECL)
2481 /* Extern inline functions don't become needed when referenced.
2482 If we know a method will be emitted in other TU and no new
2483 functions can be marked reachable, just use the external
2484 definition. */
2485 struct cgraph_node *node = cgraph_node::get_create (decl);
2486 if (!DECL_EXTERNAL (decl)
2487 && !node->definition)
2488 node->mark_force_output ();
2490 else if (VAR_P (decl))
2492 varpool_node *node = varpool_node::get_create (decl);
2493 /* C++ frontend use mark_decl_references to force COMDAT variables
2494 to be output that might appear dead otherwise. */
2495 node->force_output = true;
2497 /* else do nothing - we can get various sorts of CST nodes here,
2498 which do not need to be marked. */
2502 /* Output to FILE (an assembly file) a reference to NAME. If NAME
2503 starts with a *, the rest of NAME is output verbatim. Otherwise
2504 NAME is transformed in a target-specific way (usually by the
2505 addition of an underscore). */
2507 void
2508 assemble_name_raw (FILE *file, const char *name)
2510 if (name[0] == '*')
2511 fputs (&name[1], file);
2512 else
2513 ASM_OUTPUT_LABELREF (file, name);
2516 /* Like assemble_name_raw, but should be used when NAME might refer to
2517 an entity that is also represented as a tree (like a function or
2518 variable). If NAME does refer to such an entity, that entity will
2519 be marked as referenced. */
2521 void
2522 assemble_name (FILE *file, const char *name)
2524 const char *real_name;
2525 tree id;
2527 real_name = targetm.strip_name_encoding (name);
2529 id = maybe_get_identifier (real_name);
2530 if (id)
2532 tree id_orig = id;
2534 mark_referenced (id);
2535 ultimate_transparent_alias_target (&id);
2536 if (id != id_orig)
2537 name = IDENTIFIER_POINTER (id);
2538 gcc_assert (! TREE_CHAIN (id));
2541 assemble_name_raw (file, name);
2544 /* Allocate SIZE bytes writable static space with a gensym name
2545 and return an RTX to refer to its address. */
2548 assemble_static_space (unsigned HOST_WIDE_INT size)
2550 char name[16];
2551 const char *namestring;
2552 rtx x;
2554 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2555 ++const_labelno;
2556 namestring = ggc_strdup (name);
2558 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2559 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2561 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2562 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2563 BIGGEST_ALIGNMENT);
2564 #else
2565 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2566 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2567 #else
2569 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2570 so that each uninitialized object starts on such a boundary. */
2571 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2572 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2573 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2574 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2575 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2576 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2578 #endif
2579 #endif
2580 return x;
2583 /* Assemble the static constant template for function entry trampolines.
2584 This is done at most once per compilation.
2585 Returns an RTX for the address of the template. */
2587 static GTY(()) rtx initial_trampoline;
2590 assemble_trampoline_template (void)
2592 char label[256];
2593 const char *name;
2594 int align;
2595 rtx symbol;
2597 gcc_assert (targetm.asm_out.trampoline_template != NULL);
2599 if (initial_trampoline)
2600 return initial_trampoline;
2602 /* By default, put trampoline templates in read-only data section. */
2604 #ifdef TRAMPOLINE_SECTION
2605 switch_to_section (TRAMPOLINE_SECTION);
2606 #else
2607 switch_to_section (readonly_data_section);
2608 #endif
2610 /* Write the assembler code to define one. */
2611 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2612 if (align > 0)
2613 ASM_OUTPUT_ALIGN (asm_out_file, align);
2615 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2616 targetm.asm_out.trampoline_template (asm_out_file);
2618 /* Record the rtl to refer to it. */
2619 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2620 name = ggc_strdup (label);
2621 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2622 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2624 initial_trampoline = gen_const_mem (BLKmode, symbol);
2625 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2626 set_mem_size (initial_trampoline, TRAMPOLINE_SIZE);
2628 return initial_trampoline;
2631 /* A and B are either alignments or offsets. Return the minimum alignment
2632 that may be assumed after adding the two together. */
2634 static inline unsigned
2635 min_align (unsigned int a, unsigned int b)
2637 return least_bit_hwi (a | b);
2640 /* Return the assembler directive for creating a given kind of integer
2641 object. SIZE is the number of bytes in the object and ALIGNED_P
2642 indicates whether it is known to be aligned. Return NULL if the
2643 assembly dialect has no such directive.
2645 The returned string should be printed at the start of a new line and
2646 be followed immediately by the object's initial value. */
2648 const char *
2649 integer_asm_op (int size, int aligned_p)
2651 struct asm_int_op *ops;
2653 if (aligned_p)
2654 ops = &targetm.asm_out.aligned_op;
2655 else
2656 ops = &targetm.asm_out.unaligned_op;
2658 switch (size)
2660 case 1:
2661 return targetm.asm_out.byte_op;
2662 case 2:
2663 return ops->hi;
2664 case 4:
2665 return ops->si;
2666 case 8:
2667 return ops->di;
2668 case 16:
2669 return ops->ti;
2670 default:
2671 return NULL;
2675 /* Use directive OP to assemble an integer object X. Print OP at the
2676 start of the line, followed immediately by the value of X. */
2678 void
2679 assemble_integer_with_op (const char *op, rtx x)
2681 fputs (op, asm_out_file);
2682 output_addr_const (asm_out_file, x);
2683 fputc ('\n', asm_out_file);
2686 /* The default implementation of the asm_out.integer target hook. */
2688 bool
2689 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2690 unsigned int size ATTRIBUTE_UNUSED,
2691 int aligned_p ATTRIBUTE_UNUSED)
2693 const char *op = integer_asm_op (size, aligned_p);
2694 /* Avoid GAS bugs for large values. Specifically negative values whose
2695 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2696 if (size > UNITS_PER_WORD && size > POINTER_SIZE_UNITS)
2697 return false;
2698 return op && (assemble_integer_with_op (op, x), true);
2701 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2702 the alignment of the integer in bits. Return 1 if we were able to output
2703 the constant, otherwise 0. We must be able to output the constant,
2704 if FORCE is nonzero. */
2706 bool
2707 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2709 int aligned_p;
2711 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2713 /* See if the target hook can handle this kind of object. */
2714 if (targetm.asm_out.integer (x, size, aligned_p))
2715 return true;
2717 /* If the object is a multi-byte one, try splitting it up. Split
2718 it into words it if is multi-word, otherwise split it into bytes. */
2719 if (size > 1)
2721 machine_mode omode, imode;
2722 unsigned int subalign;
2723 unsigned int subsize, i;
2724 enum mode_class mclass;
2726 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2727 subalign = MIN (align, subsize * BITS_PER_UNIT);
2728 if (GET_CODE (x) == CONST_FIXED)
2729 mclass = GET_MODE_CLASS (GET_MODE (x));
2730 else
2731 mclass = MODE_INT;
2733 omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0);
2734 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0);
2736 for (i = 0; i < size; i += subsize)
2738 rtx partial = simplify_subreg (omode, x, imode, i);
2739 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2740 break;
2742 if (i == size)
2743 return true;
2745 /* If we've printed some of it, but not all of it, there's no going
2746 back now. */
2747 gcc_assert (!i);
2750 gcc_assert (!force);
2752 return false;
2755 /* Assemble the floating-point constant D into an object of size MODE. ALIGN
2756 is the alignment of the constant in bits. If REVERSE is true, D is output
2757 in reverse storage order. */
2759 void
2760 assemble_real (REAL_VALUE_TYPE d, machine_mode mode, unsigned int align,
2761 bool reverse)
2763 long data[4] = {0, 0, 0, 0};
2764 int bitsize, nelts, nunits, units_per;
2765 rtx elt;
2767 /* This is hairy. We have a quantity of known size. real_to_target
2768 will put it into an array of *host* longs, 32 bits per element
2769 (even if long is more than 32 bits). We need to determine the
2770 number of array elements that are occupied (nelts) and the number
2771 of *target* min-addressable units that will be occupied in the
2772 object file (nunits). We cannot assume that 32 divides the
2773 mode's bitsize (size * BITS_PER_UNIT) evenly.
2775 size * BITS_PER_UNIT is used here to make sure that padding bits
2776 (which might appear at either end of the value; real_to_target
2777 will include the padding bits in its output array) are included. */
2779 nunits = GET_MODE_SIZE (mode);
2780 bitsize = nunits * BITS_PER_UNIT;
2781 nelts = CEIL (bitsize, 32);
2782 units_per = 32 / BITS_PER_UNIT;
2784 real_to_target (data, &d, mode);
2786 /* Put out the first word with the specified alignment. */
2787 if (reverse)
2788 elt = flip_storage_order (SImode, gen_int_mode (data[nelts - 1], SImode));
2789 else
2790 elt = GEN_INT (data[0]);
2791 assemble_integer (elt, MIN (nunits, units_per), align, 1);
2792 nunits -= units_per;
2794 /* Subsequent words need only 32-bit alignment. */
2795 align = min_align (align, 32);
2797 for (int i = 1; i < nelts; i++)
2799 if (reverse)
2800 elt = flip_storage_order (SImode,
2801 gen_int_mode (data[nelts - 1 - i], SImode));
2802 else
2803 elt = GEN_INT (data[i]);
2804 assemble_integer (elt, MIN (nunits, units_per), align, 1);
2805 nunits -= units_per;
2809 /* Given an expression EXP with a constant value,
2810 reduce it to the sum of an assembler symbol and an integer.
2811 Store them both in the structure *VALUE.
2812 EXP must be reducible. */
2814 struct addr_const {
2815 rtx base;
2816 HOST_WIDE_INT offset;
2819 static void
2820 decode_addr_const (tree exp, struct addr_const *value)
2822 tree target = TREE_OPERAND (exp, 0);
2823 int offset = 0;
2824 rtx x;
2826 while (1)
2828 if (TREE_CODE (target) == COMPONENT_REF
2829 && tree_fits_shwi_p (byte_position (TREE_OPERAND (target, 1))))
2831 offset += int_byte_position (TREE_OPERAND (target, 1));
2832 target = TREE_OPERAND (target, 0);
2834 else if (TREE_CODE (target) == ARRAY_REF
2835 || TREE_CODE (target) == ARRAY_RANGE_REF)
2837 offset += (tree_to_uhwi (TYPE_SIZE_UNIT (TREE_TYPE (target)))
2838 * tree_to_shwi (TREE_OPERAND (target, 1)));
2839 target = TREE_OPERAND (target, 0);
2841 else if (TREE_CODE (target) == MEM_REF
2842 && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR)
2844 offset += mem_ref_offset (target).to_short_addr ();
2845 target = TREE_OPERAND (TREE_OPERAND (target, 0), 0);
2847 else if (TREE_CODE (target) == INDIRECT_REF
2848 && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR
2849 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0))
2850 == ADDR_EXPR)
2851 target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0);
2852 else
2853 break;
2856 switch (TREE_CODE (target))
2858 case VAR_DECL:
2859 case FUNCTION_DECL:
2860 x = DECL_RTL (target);
2861 break;
2863 case LABEL_DECL:
2864 x = gen_rtx_MEM (FUNCTION_MODE,
2865 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2866 break;
2868 case REAL_CST:
2869 case FIXED_CST:
2870 case STRING_CST:
2871 case COMPLEX_CST:
2872 case CONSTRUCTOR:
2873 case INTEGER_CST:
2874 x = output_constant_def (target, 1);
2875 break;
2877 default:
2878 gcc_unreachable ();
2881 gcc_assert (MEM_P (x));
2882 x = XEXP (x, 0);
2884 value->base = x;
2885 value->offset = offset;
2888 static GTY(()) hash_table<tree_descriptor_hasher> *const_desc_htab;
2890 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2892 /* Constant pool accessor function. */
2894 hash_table<tree_descriptor_hasher> *
2895 constant_pool_htab (void)
2897 return const_desc_htab;
2900 /* Compute a hash code for a constant expression. */
2902 hashval_t
2903 tree_descriptor_hasher::hash (constant_descriptor_tree *ptr)
2905 return ptr->hash;
2908 static hashval_t
2909 const_hash_1 (const tree exp)
2911 const char *p;
2912 hashval_t hi;
2913 int len, i;
2914 enum tree_code code = TREE_CODE (exp);
2916 /* Either set P and LEN to the address and len of something to hash and
2917 exit the switch or return a value. */
2919 switch (code)
2921 case INTEGER_CST:
2922 p = (char *) &TREE_INT_CST_ELT (exp, 0);
2923 len = TREE_INT_CST_NUNITS (exp) * sizeof (HOST_WIDE_INT);
2924 break;
2926 case REAL_CST:
2927 return real_hash (TREE_REAL_CST_PTR (exp));
2929 case FIXED_CST:
2930 return fixed_hash (TREE_FIXED_CST_PTR (exp));
2932 case STRING_CST:
2933 p = TREE_STRING_POINTER (exp);
2934 len = TREE_STRING_LENGTH (exp);
2935 break;
2937 case COMPLEX_CST:
2938 return (const_hash_1 (TREE_REALPART (exp)) * 5
2939 + const_hash_1 (TREE_IMAGPART (exp)));
2941 case VECTOR_CST:
2943 unsigned i;
2945 hi = 7 + VECTOR_CST_NELTS (exp);
2947 for (i = 0; i < VECTOR_CST_NELTS (exp); ++i)
2948 hi = hi * 563 + const_hash_1 (VECTOR_CST_ELT (exp, i));
2950 return hi;
2953 case CONSTRUCTOR:
2955 unsigned HOST_WIDE_INT idx;
2956 tree value;
2958 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2960 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
2961 if (value)
2962 hi = hi * 603 + const_hash_1 (value);
2964 return hi;
2967 case ADDR_EXPR:
2968 case FDESC_EXPR:
2970 struct addr_const value;
2972 decode_addr_const (exp, &value);
2973 switch (GET_CODE (value.base))
2975 case SYMBOL_REF:
2976 /* Don't hash the address of the SYMBOL_REF;
2977 only use the offset and the symbol name. */
2978 hi = value.offset;
2979 p = XSTR (value.base, 0);
2980 for (i = 0; p[i] != 0; i++)
2981 hi = ((hi * 613) + (unsigned) (p[i]));
2982 break;
2984 case LABEL_REF:
2985 hi = (value.offset
2986 + CODE_LABEL_NUMBER (label_ref_label (value.base)) * 13);
2987 break;
2989 default:
2990 gcc_unreachable ();
2993 return hi;
2995 case PLUS_EXPR:
2996 case POINTER_PLUS_EXPR:
2997 case MINUS_EXPR:
2998 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2999 + const_hash_1 (TREE_OPERAND (exp, 1)));
3001 CASE_CONVERT:
3002 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
3004 default:
3005 /* A language specific constant. Just hash the code. */
3006 return code;
3009 /* Compute hashing function. */
3010 hi = len;
3011 for (i = 0; i < len; i++)
3012 hi = ((hi * 613) + (unsigned) (p[i]));
3014 return hi;
3017 /* Wrapper of compare_constant, for the htab interface. */
3018 bool
3019 tree_descriptor_hasher::equal (constant_descriptor_tree *c1,
3020 constant_descriptor_tree *c2)
3022 if (c1->hash != c2->hash)
3023 return 0;
3024 return compare_constant (c1->value, c2->value);
3027 /* Compare t1 and t2, and return 1 only if they are known to result in
3028 the same bit pattern on output. */
3030 static int
3031 compare_constant (const tree t1, const tree t2)
3033 enum tree_code typecode;
3035 if (t1 == NULL_TREE)
3036 return t2 == NULL_TREE;
3037 if (t2 == NULL_TREE)
3038 return 0;
3040 if (TREE_CODE (t1) != TREE_CODE (t2))
3041 return 0;
3043 switch (TREE_CODE (t1))
3045 case INTEGER_CST:
3046 /* Integer constants are the same only if the same width of type. */
3047 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3048 return 0;
3049 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3050 return 0;
3051 return tree_int_cst_equal (t1, t2);
3053 case REAL_CST:
3054 /* Real constants are the same only if the same width of type. */
3055 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3056 return 0;
3058 return real_identical (&TREE_REAL_CST (t1), &TREE_REAL_CST (t2));
3060 case FIXED_CST:
3061 /* Fixed constants are the same only if the same width of type. */
3062 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3063 return 0;
3065 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
3067 case STRING_CST:
3068 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3069 return 0;
3071 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
3072 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
3073 TREE_STRING_LENGTH (t1)));
3075 case COMPLEX_CST:
3076 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
3077 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
3079 case VECTOR_CST:
3081 unsigned i;
3083 if (VECTOR_CST_NELTS (t1) != VECTOR_CST_NELTS (t2))
3084 return 0;
3086 for (i = 0; i < VECTOR_CST_NELTS (t1); ++i)
3087 if (!compare_constant (VECTOR_CST_ELT (t1, i),
3088 VECTOR_CST_ELT (t2, i)))
3089 return 0;
3091 return 1;
3094 case CONSTRUCTOR:
3096 vec<constructor_elt, va_gc> *v1, *v2;
3097 unsigned HOST_WIDE_INT idx;
3099 typecode = TREE_CODE (TREE_TYPE (t1));
3100 if (typecode != TREE_CODE (TREE_TYPE (t2)))
3101 return 0;
3103 if (typecode == ARRAY_TYPE)
3105 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
3106 /* For arrays, check that mode, size and storage order match. */
3107 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
3108 || size_1 == -1
3109 || size_1 != int_size_in_bytes (TREE_TYPE (t2))
3110 || TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (t1))
3111 != TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (t2)))
3112 return 0;
3114 else
3116 /* For record and union constructors, require exact type
3117 equality. */
3118 if (TREE_TYPE (t1) != TREE_TYPE (t2))
3119 return 0;
3122 v1 = CONSTRUCTOR_ELTS (t1);
3123 v2 = CONSTRUCTOR_ELTS (t2);
3124 if (vec_safe_length (v1) != vec_safe_length (v2))
3125 return 0;
3127 for (idx = 0; idx < vec_safe_length (v1); ++idx)
3129 constructor_elt *c1 = &(*v1)[idx];
3130 constructor_elt *c2 = &(*v2)[idx];
3132 /* Check that each value is the same... */
3133 if (!compare_constant (c1->value, c2->value))
3134 return 0;
3135 /* ... and that they apply to the same fields! */
3136 if (typecode == ARRAY_TYPE)
3138 if (!compare_constant (c1->index, c2->index))
3139 return 0;
3141 else
3143 if (c1->index != c2->index)
3144 return 0;
3148 return 1;
3151 case ADDR_EXPR:
3152 case FDESC_EXPR:
3154 struct addr_const value1, value2;
3155 enum rtx_code code;
3156 int ret;
3158 decode_addr_const (t1, &value1);
3159 decode_addr_const (t2, &value2);
3161 if (value1.offset != value2.offset)
3162 return 0;
3164 code = GET_CODE (value1.base);
3165 if (code != GET_CODE (value2.base))
3166 return 0;
3168 switch (code)
3170 case SYMBOL_REF:
3171 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3172 break;
3174 case LABEL_REF:
3175 ret = (CODE_LABEL_NUMBER (label_ref_label (value1.base))
3176 == CODE_LABEL_NUMBER (label_ref_label (value2.base)));
3177 break;
3179 default:
3180 gcc_unreachable ();
3182 return ret;
3185 case PLUS_EXPR:
3186 case POINTER_PLUS_EXPR:
3187 case MINUS_EXPR:
3188 case RANGE_EXPR:
3189 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3190 && compare_constant (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3192 CASE_CONVERT:
3193 case VIEW_CONVERT_EXPR:
3194 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3196 default:
3197 return 0;
3200 gcc_unreachable ();
3203 /* Return the section into which constant EXP should be placed. */
3205 static section *
3206 get_constant_section (tree exp, unsigned int align)
3208 return targetm.asm_out.select_section (exp,
3209 compute_reloc_for_constant (exp),
3210 align);
3213 /* Return the size of constant EXP in bytes. */
3215 static HOST_WIDE_INT
3216 get_constant_size (tree exp)
3218 HOST_WIDE_INT size;
3220 size = int_size_in_bytes (TREE_TYPE (exp));
3221 if (TREE_CODE (exp) == STRING_CST)
3222 size = MAX (TREE_STRING_LENGTH (exp), size);
3223 return size;
3226 /* Subroutine of output_constant_def:
3227 No constant equal to EXP is known to have been output.
3228 Make a constant descriptor to enter EXP in the hash table.
3229 Assign the label number and construct RTL to refer to the
3230 constant's location in memory.
3231 Caller is responsible for updating the hash table. */
3233 static struct constant_descriptor_tree *
3234 build_constant_desc (tree exp)
3236 struct constant_descriptor_tree *desc;
3237 rtx symbol, rtl;
3238 char label[256];
3239 int labelno;
3240 tree decl;
3242 desc = ggc_alloc<constant_descriptor_tree> ();
3243 desc->value = exp;
3245 /* Create a string containing the label name, in LABEL. */
3246 labelno = const_labelno++;
3247 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3249 /* Construct the VAR_DECL associated with the constant. */
3250 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3251 TREE_TYPE (exp));
3252 DECL_ARTIFICIAL (decl) = 1;
3253 DECL_IGNORED_P (decl) = 1;
3254 TREE_READONLY (decl) = 1;
3255 TREE_STATIC (decl) = 1;
3256 TREE_ADDRESSABLE (decl) = 1;
3257 /* We don't set the RTL yet as this would cause varpool to assume that the
3258 variable is referenced. Moreover, it would just be dropped in LTO mode.
3259 Instead we set the flag that will be recognized in make_decl_rtl. */
3260 DECL_IN_CONSTANT_POOL (decl) = 1;
3261 DECL_INITIAL (decl) = desc->value;
3262 /* ??? CONSTANT_ALIGNMENT hasn't been updated for vector types on most
3263 architectures so use DATA_ALIGNMENT as well, except for strings. */
3264 if (TREE_CODE (exp) == STRING_CST)
3266 SET_DECL_ALIGN (decl, CONSTANT_ALIGNMENT (exp, DECL_ALIGN (decl)));
3268 else
3269 align_variable (decl, 0);
3271 /* Now construct the SYMBOL_REF and the MEM. */
3272 if (use_object_blocks_p ())
3274 int align = (TREE_CODE (decl) == CONST_DECL
3275 || (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
3276 ? DECL_ALIGN (decl)
3277 : symtab_node::get (decl)->definition_alignment ());
3278 section *sect = get_constant_section (exp, align);
3279 symbol = create_block_symbol (ggc_strdup (label),
3280 get_block_for_section (sect), -1);
3282 else
3283 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3284 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3285 SET_SYMBOL_REF_DECL (symbol, decl);
3286 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3288 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3289 set_mem_attributes (rtl, exp, 1);
3290 set_mem_alias_set (rtl, 0);
3292 /* We cannot share RTX'es in pool entries.
3293 Mark this piece of RTL as required for unsharing. */
3294 RTX_FLAG (rtl, used) = 1;
3296 /* Set flags or add text to the name to record information, such as
3297 that it is a local symbol. If the name is changed, the macro
3298 ASM_OUTPUT_LABELREF will have to know how to strip this
3299 information. This call might invalidate our local variable
3300 SYMBOL; we can't use it afterward. */
3301 targetm.encode_section_info (exp, rtl, true);
3303 desc->rtl = rtl;
3305 return desc;
3308 /* Return an rtx representing a reference to constant data in memory
3309 for the constant expression EXP.
3311 If assembler code for such a constant has already been output,
3312 return an rtx to refer to it.
3313 Otherwise, output such a constant in memory
3314 and generate an rtx for it.
3316 If DEFER is nonzero, this constant can be deferred and output only
3317 if referenced in the function after all optimizations.
3319 `const_desc_table' records which constants already have label strings. */
3322 output_constant_def (tree exp, int defer)
3324 struct constant_descriptor_tree *desc;
3325 struct constant_descriptor_tree key;
3327 /* Look up EXP in the table of constant descriptors. If we didn't find
3328 it, create a new one. */
3329 key.value = exp;
3330 key.hash = const_hash_1 (exp);
3331 constant_descriptor_tree **loc
3332 = const_desc_htab->find_slot_with_hash (&key, key.hash, INSERT);
3334 desc = *loc;
3335 if (desc == 0)
3337 desc = build_constant_desc (exp);
3338 desc->hash = key.hash;
3339 *loc = desc;
3342 maybe_output_constant_def_contents (desc, defer);
3343 return desc->rtl;
3346 /* Subroutine of output_constant_def: Decide whether or not we need to
3347 output the constant DESC now, and if so, do it. */
3348 static void
3349 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3350 int defer)
3352 rtx symbol = XEXP (desc->rtl, 0);
3353 tree exp = desc->value;
3355 if (flag_syntax_only)
3356 return;
3358 if (TREE_ASM_WRITTEN (exp))
3359 /* Already output; don't do it again. */
3360 return;
3362 /* We can always defer constants as long as the context allows
3363 doing so. */
3364 if (defer)
3366 /* Increment n_deferred_constants if it exists. It needs to be at
3367 least as large as the number of constants actually referred to
3368 by the function. If it's too small we'll stop looking too early
3369 and fail to emit constants; if it's too large we'll only look
3370 through the entire function when we could have stopped earlier. */
3371 if (cfun)
3372 n_deferred_constants++;
3373 return;
3376 output_constant_def_contents (symbol);
3379 /* Subroutine of output_constant_def_contents. Output the definition
3380 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3381 constant's alignment in bits. */
3383 static void
3384 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3386 HOST_WIDE_INT size;
3388 size = get_constant_size (exp);
3390 /* Do any machine/system dependent processing of the constant. */
3391 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3393 /* Output the value of EXP. */
3394 output_constant (exp, size, align, false);
3396 targetm.asm_out.decl_end ();
3399 /* We must output the constant data referred to by SYMBOL; do so. */
3401 static void
3402 output_constant_def_contents (rtx symbol)
3404 tree decl = SYMBOL_REF_DECL (symbol);
3405 tree exp = DECL_INITIAL (decl);
3406 bool asan_protected = false;
3408 /* Make sure any other constants whose addresses appear in EXP
3409 are assigned label numbers. */
3410 output_addressed_constants (exp);
3412 /* We are no longer deferring this constant. */
3413 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3415 if ((flag_sanitize & SANITIZE_ADDRESS)
3416 && TREE_CODE (exp) == STRING_CST
3417 && asan_protect_global (exp))
3419 asan_protected = true;
3420 SET_DECL_ALIGN (decl, MAX (DECL_ALIGN (decl),
3421 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT));
3424 /* If the constant is part of an object block, make sure that the
3425 decl has been positioned within its block, but do not write out
3426 its definition yet. output_object_blocks will do that later. */
3427 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3428 place_block_symbol (symbol);
3429 else
3431 int align = (TREE_CODE (decl) == CONST_DECL
3432 || (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
3433 ? DECL_ALIGN (decl)
3434 : symtab_node::get (decl)->definition_alignment ());
3435 switch_to_section (get_constant_section (exp, align));
3436 if (align > BITS_PER_UNIT)
3437 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3438 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3439 if (asan_protected)
3441 HOST_WIDE_INT size = get_constant_size (exp);
3442 assemble_zeros (asan_red_zone_size (size));
3447 /* Look up EXP in the table of constant descriptors. Return the rtl
3448 if it has been emitted, else null. */
3451 lookup_constant_def (tree exp)
3453 struct constant_descriptor_tree key;
3455 key.value = exp;
3456 key.hash = const_hash_1 (exp);
3457 constant_descriptor_tree *desc
3458 = const_desc_htab->find_with_hash (&key, key.hash);
3460 return (desc ? desc->rtl : NULL_RTX);
3463 /* Return a tree representing a reference to constant data in memory
3464 for the constant expression EXP.
3466 This is the counterpart of output_constant_def at the Tree level. */
3468 tree
3469 tree_output_constant_def (tree exp)
3471 struct constant_descriptor_tree *desc, key;
3472 tree decl;
3474 /* Look up EXP in the table of constant descriptors. If we didn't find
3475 it, create a new one. */
3476 key.value = exp;
3477 key.hash = const_hash_1 (exp);
3478 constant_descriptor_tree **loc
3479 = const_desc_htab->find_slot_with_hash (&key, key.hash, INSERT);
3481 desc = *loc;
3482 if (desc == 0)
3484 desc = build_constant_desc (exp);
3485 desc->hash = key.hash;
3486 *loc = desc;
3489 decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3490 varpool_node::finalize_decl (decl);
3491 return decl;
3494 struct GTY((chain_next ("%h.next"), for_user)) constant_descriptor_rtx {
3495 struct constant_descriptor_rtx *next;
3496 rtx mem;
3497 rtx sym;
3498 rtx constant;
3499 HOST_WIDE_INT offset;
3500 hashval_t hash;
3501 machine_mode mode;
3502 unsigned int align;
3503 int labelno;
3504 int mark;
3507 struct const_rtx_desc_hasher : ggc_ptr_hash<constant_descriptor_rtx>
3509 static hashval_t hash (constant_descriptor_rtx *);
3510 static bool equal (constant_descriptor_rtx *, constant_descriptor_rtx *);
3513 /* Used in the hash tables to avoid outputting the same constant
3514 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3515 are output once per function, not once per file. */
3516 /* ??? Only a few targets need per-function constant pools. Most
3517 can use one per-file pool. Should add a targetm bit to tell the
3518 difference. */
3520 struct GTY(()) rtx_constant_pool {
3521 /* Pointers to first and last constant in pool, as ordered by offset. */
3522 struct constant_descriptor_rtx *first;
3523 struct constant_descriptor_rtx *last;
3525 /* Hash facility for making memory-constants from constant rtl-expressions.
3526 It is used on RISC machines where immediate integer arguments and
3527 constant addresses are restricted so that such constants must be stored
3528 in memory. */
3529 hash_table<const_rtx_desc_hasher> *const_rtx_htab;
3531 /* Current offset in constant pool (does not include any
3532 machine-specific header). */
3533 HOST_WIDE_INT offset;
3536 /* Hash and compare functions for const_rtx_htab. */
3538 hashval_t
3539 const_rtx_desc_hasher::hash (constant_descriptor_rtx *desc)
3541 return desc->hash;
3544 bool
3545 const_rtx_desc_hasher::equal (constant_descriptor_rtx *x,
3546 constant_descriptor_rtx *y)
3548 if (x->mode != y->mode)
3549 return 0;
3550 return rtx_equal_p (x->constant, y->constant);
3553 /* Hash one component of a constant. */
3555 static hashval_t
3556 const_rtx_hash_1 (const_rtx x)
3558 unsigned HOST_WIDE_INT hwi;
3559 machine_mode mode;
3560 enum rtx_code code;
3561 hashval_t h;
3562 int i;
3564 code = GET_CODE (x);
3565 mode = GET_MODE (x);
3566 h = (hashval_t) code * 1048573 + mode;
3568 switch (code)
3570 case CONST_INT:
3571 hwi = INTVAL (x);
3573 fold_hwi:
3575 int shift = sizeof (hashval_t) * CHAR_BIT;
3576 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3578 h ^= (hashval_t) hwi;
3579 for (i = 1; i < n; ++i)
3581 hwi >>= shift;
3582 h ^= (hashval_t) hwi;
3585 break;
3587 case CONST_WIDE_INT:
3588 hwi = GET_MODE_PRECISION (mode);
3590 for (i = 0; i < CONST_WIDE_INT_NUNITS (x); i++)
3591 hwi ^= CONST_WIDE_INT_ELT (x, i);
3592 goto fold_hwi;
3595 case CONST_DOUBLE:
3596 if (TARGET_SUPPORTS_WIDE_INT == 0 && mode == VOIDmode)
3598 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3599 goto fold_hwi;
3601 else
3602 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3603 break;
3605 case CONST_FIXED:
3606 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3607 break;
3609 case SYMBOL_REF:
3610 h ^= htab_hash_string (XSTR (x, 0));
3611 break;
3613 case LABEL_REF:
3614 h = h * 251 + CODE_LABEL_NUMBER (label_ref_label (x));
3615 break;
3617 case UNSPEC:
3618 case UNSPEC_VOLATILE:
3619 h = h * 251 + XINT (x, 1);
3620 break;
3622 default:
3623 break;
3626 return h;
3629 /* Compute a hash value for X, which should be a constant. */
3631 static hashval_t
3632 const_rtx_hash (rtx x)
3634 hashval_t h = 0;
3635 subrtx_iterator::array_type array;
3636 FOR_EACH_SUBRTX (iter, array, x, ALL)
3637 h = h * 509 + const_rtx_hash_1 (*iter);
3638 return h;
3642 /* Create and return a new rtx constant pool. */
3644 static struct rtx_constant_pool *
3645 create_constant_pool (void)
3647 struct rtx_constant_pool *pool;
3649 pool = ggc_alloc<rtx_constant_pool> ();
3650 pool->const_rtx_htab = hash_table<const_rtx_desc_hasher>::create_ggc (31);
3651 pool->first = NULL;
3652 pool->last = NULL;
3653 pool->offset = 0;
3654 return pool;
3657 /* Initialize constant pool hashing for a new function. */
3659 void
3660 init_varasm_status (void)
3662 crtl->varasm.pool = create_constant_pool ();
3663 crtl->varasm.deferred_constants = 0;
3666 /* Given a MINUS expression, simplify it if both sides
3667 include the same symbol. */
3670 simplify_subtraction (rtx x)
3672 rtx r = simplify_rtx (x);
3673 return r ? r : x;
3676 /* Given a constant rtx X, make (or find) a memory constant for its value
3677 and return a MEM rtx to refer to it in memory. */
3680 force_const_mem (machine_mode mode, rtx x)
3682 struct constant_descriptor_rtx *desc, tmp;
3683 struct rtx_constant_pool *pool;
3684 char label[256];
3685 rtx def, symbol;
3686 hashval_t hash;
3687 unsigned int align;
3688 constant_descriptor_rtx **slot;
3690 /* If we're not allowed to drop X into the constant pool, don't. */
3691 if (targetm.cannot_force_const_mem (mode, x))
3692 return NULL_RTX;
3694 /* Record that this function has used a constant pool entry. */
3695 crtl->uses_const_pool = 1;
3697 /* Decide which pool to use. */
3698 pool = (targetm.use_blocks_for_constant_p (mode, x)
3699 ? shared_constant_pool
3700 : crtl->varasm.pool);
3702 /* Lookup the value in the hashtable. */
3703 tmp.constant = x;
3704 tmp.mode = mode;
3705 hash = const_rtx_hash (x);
3706 slot = pool->const_rtx_htab->find_slot_with_hash (&tmp, hash, INSERT);
3707 desc = *slot;
3709 /* If the constant was already present, return its memory. */
3710 if (desc)
3711 return copy_rtx (desc->mem);
3713 /* Otherwise, create a new descriptor. */
3714 desc = ggc_alloc<constant_descriptor_rtx> ();
3715 *slot = desc;
3717 /* Align the location counter as required by EXP's data type. */
3718 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3720 tree type = lang_hooks.types.type_for_mode (mode, 0);
3721 if (type != NULL_TREE)
3722 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3724 pool->offset += (align / BITS_PER_UNIT) - 1;
3725 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3727 desc->next = NULL;
3728 desc->constant = copy_rtx (tmp.constant);
3729 desc->offset = pool->offset;
3730 desc->hash = hash;
3731 desc->mode = mode;
3732 desc->align = align;
3733 desc->labelno = const_labelno;
3734 desc->mark = 0;
3736 pool->offset += GET_MODE_SIZE (mode);
3737 if (pool->last)
3738 pool->last->next = desc;
3739 else
3740 pool->first = pool->last = desc;
3741 pool->last = desc;
3743 /* Create a string containing the label name, in LABEL. */
3744 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3745 ++const_labelno;
3747 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3748 the constants pool. */
3749 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3751 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3752 symbol = create_block_symbol (ggc_strdup (label),
3753 get_block_for_section (sect), -1);
3755 else
3756 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3757 desc->sym = symbol;
3758 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3759 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3760 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3762 /* Construct the MEM. */
3763 desc->mem = def = gen_const_mem (mode, symbol);
3764 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3765 set_mem_align (def, align);
3767 /* If we're dropping a label to the constant pool, make sure we
3768 don't delete it. */
3769 if (GET_CODE (x) == LABEL_REF)
3770 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3772 return copy_rtx (def);
3775 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3778 get_pool_constant (const_rtx addr)
3780 return SYMBOL_REF_CONSTANT (addr)->constant;
3783 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3784 and whether it has been output or not. */
3787 get_pool_constant_mark (rtx addr, bool *pmarked)
3789 struct constant_descriptor_rtx *desc;
3791 desc = SYMBOL_REF_CONSTANT (addr);
3792 *pmarked = (desc->mark != 0);
3793 return desc->constant;
3796 /* Similar, return the mode. */
3798 machine_mode
3799 get_pool_mode (const_rtx addr)
3801 return SYMBOL_REF_CONSTANT (addr)->mode;
3804 /* Return the size of the constant pool. */
3807 get_pool_size (void)
3809 return crtl->varasm.pool->offset;
3812 /* Worker function for output_constant_pool_1. Emit assembly for X
3813 in MODE with known alignment ALIGN. */
3815 static void
3816 output_constant_pool_2 (machine_mode mode, rtx x, unsigned int align)
3818 switch (GET_MODE_CLASS (mode))
3820 case MODE_FLOAT:
3821 case MODE_DECIMAL_FLOAT:
3823 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3824 assemble_real (*CONST_DOUBLE_REAL_VALUE (x), mode, align, false);
3825 break;
3828 case MODE_INT:
3829 case MODE_PARTIAL_INT:
3830 case MODE_FRACT:
3831 case MODE_UFRACT:
3832 case MODE_ACCUM:
3833 case MODE_UACCUM:
3834 case MODE_POINTER_BOUNDS:
3835 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3836 break;
3838 case MODE_VECTOR_FLOAT:
3839 case MODE_VECTOR_INT:
3840 case MODE_VECTOR_FRACT:
3841 case MODE_VECTOR_UFRACT:
3842 case MODE_VECTOR_ACCUM:
3843 case MODE_VECTOR_UACCUM:
3845 int i, units;
3846 machine_mode submode = GET_MODE_INNER (mode);
3847 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3849 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3850 units = CONST_VECTOR_NUNITS (x);
3852 for (i = 0; i < units; i++)
3854 rtx elt = CONST_VECTOR_ELT (x, i);
3855 output_constant_pool_2 (submode, elt, i ? subalign : align);
3858 break;
3860 default:
3861 gcc_unreachable ();
3865 /* Worker function for output_constant_pool. Emit constant DESC,
3866 giving it ALIGN bits of alignment. */
3868 static void
3869 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3870 unsigned int align)
3872 rtx x, tmp;
3874 x = desc->constant;
3876 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3877 whose CODE_LABEL has been deleted. This can occur if a jump table
3878 is eliminated by optimization. If so, write a constant of zero
3879 instead. Note that this can also happen by turning the
3880 CODE_LABEL into a NOTE. */
3881 /* ??? This seems completely and utterly wrong. Certainly it's
3882 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3883 functioning even with rtx_insn::deleted and friends. */
3885 tmp = x;
3886 switch (GET_CODE (tmp))
3888 case CONST:
3889 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3890 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
3891 break;
3892 tmp = XEXP (XEXP (tmp, 0), 0);
3893 /* FALLTHRU */
3895 case LABEL_REF:
3897 rtx_insn *insn = label_ref_label (tmp);
3898 gcc_assert (!insn->deleted ());
3899 gcc_assert (!NOTE_P (insn)
3900 || NOTE_KIND (insn) != NOTE_INSN_DELETED);
3901 break;
3904 default:
3905 break;
3908 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3909 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3910 align, desc->labelno, done);
3911 #endif
3913 assemble_align (align);
3915 /* Output the label. */
3916 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3918 /* Output the data.
3919 Pass actual alignment value while emitting string constant to asm code
3920 as function 'output_constant_pool_1' explicitly passes the alignment as 1
3921 assuming that the data is already aligned which prevents the generation
3922 of fix-up table entries. */
3923 output_constant_pool_2 (desc->mode, x, desc->align);
3925 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3926 sections have proper size. */
3927 if (align > GET_MODE_BITSIZE (desc->mode)
3928 && in_section
3929 && (in_section->common.flags & SECTION_MERGE))
3930 assemble_align (align);
3932 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3933 done:
3934 #endif
3935 return;
3938 /* Mark all constants that are referenced by SYMBOL_REFs in X.
3939 Emit referenced deferred strings. */
3941 static void
3942 mark_constants_in_pattern (rtx insn)
3944 subrtx_iterator::array_type array;
3945 FOR_EACH_SUBRTX (iter, array, PATTERN (insn), ALL)
3947 const_rtx x = *iter;
3948 if (GET_CODE (x) == SYMBOL_REF)
3950 if (CONSTANT_POOL_ADDRESS_P (x))
3952 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
3953 if (desc->mark == 0)
3955 desc->mark = 1;
3956 iter.substitute (desc->constant);
3959 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3961 tree decl = SYMBOL_REF_DECL (x);
3962 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
3964 n_deferred_constants--;
3965 output_constant_def_contents (CONST_CAST_RTX (x));
3972 /* Look through appropriate parts of INSN, marking all entries in the
3973 constant pool which are actually being used. Entries that are only
3974 referenced by other constants are also marked as used. Emit
3975 deferred strings that are used. */
3977 static void
3978 mark_constants (rtx_insn *insn)
3980 if (!INSN_P (insn))
3981 return;
3983 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3984 insns, not any notes that may be attached. We don't want to mark
3985 a constant just because it happens to appear in a REG_EQUIV note. */
3986 if (rtx_sequence *seq = dyn_cast <rtx_sequence *> (PATTERN (insn)))
3988 int i, n = seq->len ();
3989 for (i = 0; i < n; ++i)
3991 rtx subinsn = seq->element (i);
3992 if (INSN_P (subinsn))
3993 mark_constants_in_pattern (subinsn);
3996 else
3997 mark_constants_in_pattern (insn);
4000 /* Look through the instructions for this function, and mark all the
4001 entries in POOL which are actually being used. Emit deferred constants
4002 which have indeed been used. */
4004 static void
4005 mark_constant_pool (void)
4007 rtx_insn *insn;
4009 if (!crtl->uses_const_pool && n_deferred_constants == 0)
4010 return;
4012 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4013 mark_constants (insn);
4016 /* Write all the constants in POOL. */
4018 static void
4019 output_constant_pool_contents (struct rtx_constant_pool *pool)
4021 struct constant_descriptor_rtx *desc;
4023 for (desc = pool->first; desc ; desc = desc->next)
4024 if (desc->mark)
4026 /* If the constant is part of an object_block, make sure that
4027 the constant has been positioned within its block, but do not
4028 write out its definition yet. output_object_blocks will do
4029 that later. */
4030 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
4031 && SYMBOL_REF_BLOCK (desc->sym))
4032 place_block_symbol (desc->sym);
4033 else
4035 switch_to_section (targetm.asm_out.select_rtx_section
4036 (desc->mode, desc->constant, desc->align));
4037 output_constant_pool_1 (desc, desc->align);
4042 /* Mark all constants that are used in the current function, then write
4043 out the function's private constant pool. */
4045 static void
4046 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
4047 tree fndecl ATTRIBUTE_UNUSED)
4049 struct rtx_constant_pool *pool = crtl->varasm.pool;
4051 /* It is possible for gcc to call force_const_mem and then to later
4052 discard the instructions which refer to the constant. In such a
4053 case we do not need to output the constant. */
4054 mark_constant_pool ();
4056 #ifdef ASM_OUTPUT_POOL_PROLOGUE
4057 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
4058 #endif
4060 output_constant_pool_contents (pool);
4062 #ifdef ASM_OUTPUT_POOL_EPILOGUE
4063 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
4064 #endif
4067 /* Write the contents of the shared constant pool. */
4069 void
4070 output_shared_constant_pool (void)
4072 output_constant_pool_contents (shared_constant_pool);
4075 /* Determine what kind of relocations EXP may need. */
4078 compute_reloc_for_constant (tree exp)
4080 int reloc = 0, reloc2;
4081 tree tem;
4083 switch (TREE_CODE (exp))
4085 case ADDR_EXPR:
4086 case FDESC_EXPR:
4087 /* Go inside any operations that get_inner_reference can handle and see
4088 if what's inside is a constant: no need to do anything here for
4089 addresses of variables or functions. */
4090 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4091 tem = TREE_OPERAND (tem, 0))
4094 if (TREE_CODE (tem) == MEM_REF
4095 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4097 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4098 break;
4101 if (!targetm.binds_local_p (tem))
4102 reloc |= 2;
4103 else
4104 reloc |= 1;
4105 break;
4107 case PLUS_EXPR:
4108 case POINTER_PLUS_EXPR:
4109 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4110 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4111 break;
4113 case MINUS_EXPR:
4114 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4115 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4116 /* The difference of two local labels is computable at link time. */
4117 if (reloc == 1 && reloc2 == 1)
4118 reloc = 0;
4119 else
4120 reloc |= reloc2;
4121 break;
4123 CASE_CONVERT:
4124 case VIEW_CONVERT_EXPR:
4125 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4126 break;
4128 case CONSTRUCTOR:
4130 unsigned HOST_WIDE_INT idx;
4131 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4132 if (tem != 0)
4133 reloc |= compute_reloc_for_constant (tem);
4135 break;
4137 default:
4138 break;
4140 return reloc;
4143 /* Find all the constants whose addresses are referenced inside of EXP,
4144 and make sure assembler code with a label has been output for each one.
4145 Indicate whether an ADDR_EXPR has been encountered. */
4147 static void
4148 output_addressed_constants (tree exp)
4150 tree tem;
4152 switch (TREE_CODE (exp))
4154 case ADDR_EXPR:
4155 case FDESC_EXPR:
4156 /* Go inside any operations that get_inner_reference can handle and see
4157 if what's inside is a constant: no need to do anything here for
4158 addresses of variables or functions. */
4159 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4160 tem = TREE_OPERAND (tem, 0))
4163 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4164 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4165 tem = DECL_INITIAL (tem);
4167 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4168 output_constant_def (tem, 0);
4170 if (TREE_CODE (tem) == MEM_REF)
4171 output_addressed_constants (TREE_OPERAND (tem, 0));
4172 break;
4174 case PLUS_EXPR:
4175 case POINTER_PLUS_EXPR:
4176 case MINUS_EXPR:
4177 output_addressed_constants (TREE_OPERAND (exp, 1));
4178 gcc_fallthrough ();
4180 CASE_CONVERT:
4181 case VIEW_CONVERT_EXPR:
4182 output_addressed_constants (TREE_OPERAND (exp, 0));
4183 break;
4185 case CONSTRUCTOR:
4187 unsigned HOST_WIDE_INT idx;
4188 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4189 if (tem != 0)
4190 output_addressed_constants (tem);
4192 break;
4194 default:
4195 break;
4199 /* Whether a constructor CTOR is a valid static constant initializer if all
4200 its elements are. This used to be internal to initializer_constant_valid_p
4201 and has been exposed to let other functions like categorize_ctor_elements
4202 evaluate the property while walking a constructor for other purposes. */
4204 bool
4205 constructor_static_from_elts_p (const_tree ctor)
4207 return (TREE_CONSTANT (ctor)
4208 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4209 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4210 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4213 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4214 tree *cache);
4216 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4217 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4218 which are valid when ENDTYPE is an integer of any size; in
4219 particular, this does not accept a pointer minus a constant. This
4220 returns null_pointer_node if the VALUE is an absolute constant
4221 which can be used to initialize a static variable. Otherwise it
4222 returns NULL. */
4224 static tree
4225 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4227 tree op0, op1;
4229 if (!INTEGRAL_TYPE_P (endtype))
4230 return NULL_TREE;
4232 op0 = TREE_OPERAND (value, 0);
4233 op1 = TREE_OPERAND (value, 1);
4235 /* Like STRIP_NOPS except allow the operand mode to widen. This
4236 works around a feature of fold that simplifies (int)(p1 - p2) to
4237 ((int)p1 - (int)p2) under the theory that the narrower operation
4238 is cheaper. */
4240 while (CONVERT_EXPR_P (op0)
4241 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4243 tree inner = TREE_OPERAND (op0, 0);
4244 if (inner == error_mark_node
4245 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4246 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
4247 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4248 break;
4249 op0 = inner;
4252 while (CONVERT_EXPR_P (op1)
4253 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4255 tree inner = TREE_OPERAND (op1, 0);
4256 if (inner == error_mark_node
4257 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4258 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
4259 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4260 break;
4261 op1 = inner;
4264 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4265 if (!op0)
4266 return NULL_TREE;
4268 op1 = initializer_constant_valid_p_1 (op1, endtype,
4269 cache ? cache + 2 : NULL);
4270 /* Both initializers must be known. */
4271 if (op1)
4273 if (op0 == op1
4274 && (op0 == null_pointer_node
4275 || TREE_CODE (value) == MINUS_EXPR))
4276 return null_pointer_node;
4278 /* Support differences between labels. */
4279 if (TREE_CODE (op0) == LABEL_DECL
4280 && TREE_CODE (op1) == LABEL_DECL)
4281 return null_pointer_node;
4283 if (TREE_CODE (op0) == STRING_CST
4284 && TREE_CODE (op1) == STRING_CST
4285 && operand_equal_p (op0, op1, 1))
4286 return null_pointer_node;
4289 return NULL_TREE;
4292 /* Helper function of initializer_constant_valid_p.
4293 Return nonzero if VALUE is a valid constant-valued expression
4294 for use in initializing a static variable; one that can be an
4295 element of a "constant" initializer.
4297 Return null_pointer_node if the value is absolute;
4298 if it is relocatable, return the variable that determines the relocation.
4299 We assume that VALUE has been folded as much as possible;
4300 therefore, we do not need to check for such things as
4301 arithmetic-combinations of integers.
4303 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4305 static tree
4306 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4308 tree ret;
4310 switch (TREE_CODE (value))
4312 case CONSTRUCTOR:
4313 if (constructor_static_from_elts_p (value))
4315 unsigned HOST_WIDE_INT idx;
4316 tree elt;
4317 bool absolute = true;
4319 if (cache && cache[0] == value)
4320 return cache[1];
4321 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4323 tree reloc;
4324 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4325 NULL);
4326 if (!reloc
4327 /* An absolute value is required with reverse SSO. */
4328 || (reloc != null_pointer_node
4329 && TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (value))
4330 && !AGGREGATE_TYPE_P (TREE_TYPE (elt))))
4332 if (cache)
4334 cache[0] = value;
4335 cache[1] = NULL_TREE;
4337 return NULL_TREE;
4339 if (reloc != null_pointer_node)
4340 absolute = false;
4342 /* For a non-absolute relocation, there is no single
4343 variable that can be "the variable that determines the
4344 relocation." */
4345 if (cache)
4347 cache[0] = value;
4348 cache[1] = absolute ? null_pointer_node : error_mark_node;
4350 return absolute ? null_pointer_node : error_mark_node;
4353 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4355 case INTEGER_CST:
4356 case VECTOR_CST:
4357 case REAL_CST:
4358 case FIXED_CST:
4359 case STRING_CST:
4360 case COMPLEX_CST:
4361 return null_pointer_node;
4363 case ADDR_EXPR:
4364 case FDESC_EXPR:
4366 tree op0 = staticp (TREE_OPERAND (value, 0));
4367 if (op0)
4369 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4370 to be a constant, this is old-skool offsetof-like nonsense. */
4371 if (TREE_CODE (op0) == INDIRECT_REF
4372 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4373 return null_pointer_node;
4374 /* Taking the address of a nested function involves a trampoline,
4375 unless we don't need or want one. */
4376 if (TREE_CODE (op0) == FUNCTION_DECL
4377 && DECL_STATIC_CHAIN (op0)
4378 && !TREE_NO_TRAMPOLINE (value))
4379 return NULL_TREE;
4380 /* "&{...}" requires a temporary to hold the constructed
4381 object. */
4382 if (TREE_CODE (op0) == CONSTRUCTOR)
4383 return NULL_TREE;
4385 return op0;
4388 case NON_LVALUE_EXPR:
4389 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4390 endtype, cache);
4392 case VIEW_CONVERT_EXPR:
4394 tree src = TREE_OPERAND (value, 0);
4395 tree src_type = TREE_TYPE (src);
4396 tree dest_type = TREE_TYPE (value);
4398 /* Allow view-conversions from aggregate to non-aggregate type only
4399 if the bit pattern is fully preserved afterwards; otherwise, the
4400 RTL expander won't be able to apply a subsequent transformation
4401 to the underlying constructor. */
4402 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4404 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4405 return initializer_constant_valid_p_1 (src, endtype, cache);
4406 else
4407 return NULL_TREE;
4410 /* Allow all other kinds of view-conversion. */
4411 return initializer_constant_valid_p_1 (src, endtype, cache);
4414 CASE_CONVERT:
4416 tree src = TREE_OPERAND (value, 0);
4417 tree src_type = TREE_TYPE (src);
4418 tree dest_type = TREE_TYPE (value);
4420 /* Allow conversions between pointer types, floating-point
4421 types, and offset types. */
4422 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4423 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4424 || (TREE_CODE (dest_type) == OFFSET_TYPE
4425 && TREE_CODE (src_type) == OFFSET_TYPE))
4426 return initializer_constant_valid_p_1 (src, endtype, cache);
4428 /* Allow length-preserving conversions between integer types. */
4429 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4430 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4431 return initializer_constant_valid_p_1 (src, endtype, cache);
4433 /* Allow conversions between other integer types only if
4434 explicit value. */
4435 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type))
4437 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4438 if (inner == null_pointer_node)
4439 return null_pointer_node;
4440 break;
4443 /* Allow (int) &foo provided int is as wide as a pointer. */
4444 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4445 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4446 return initializer_constant_valid_p_1 (src, endtype, cache);
4448 /* Likewise conversions from int to pointers, but also allow
4449 conversions from 0. */
4450 if ((POINTER_TYPE_P (dest_type)
4451 || TREE_CODE (dest_type) == OFFSET_TYPE)
4452 && INTEGRAL_TYPE_P (src_type))
4454 if (TREE_CODE (src) == INTEGER_CST
4455 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4456 return null_pointer_node;
4457 if (integer_zerop (src))
4458 return null_pointer_node;
4459 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4460 return initializer_constant_valid_p_1 (src, endtype, cache);
4463 /* Allow conversions to struct or union types if the value
4464 inside is okay. */
4465 if (TREE_CODE (dest_type) == RECORD_TYPE
4466 || TREE_CODE (dest_type) == UNION_TYPE)
4467 return initializer_constant_valid_p_1 (src, endtype, cache);
4469 break;
4471 case POINTER_PLUS_EXPR:
4472 case PLUS_EXPR:
4473 /* Any valid floating-point constants will have been folded by now;
4474 with -frounding-math we hit this with addition of two constants. */
4475 if (TREE_CODE (endtype) == REAL_TYPE)
4476 return NULL_TREE;
4477 if (cache && cache[0] == value)
4478 return cache[1];
4479 if (! INTEGRAL_TYPE_P (endtype)
4480 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4482 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4483 tree valid0
4484 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4485 endtype, ncache);
4486 tree valid1
4487 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4488 endtype, ncache + 2);
4489 /* If either term is absolute, use the other term's relocation. */
4490 if (valid0 == null_pointer_node)
4491 ret = valid1;
4492 else if (valid1 == null_pointer_node)
4493 ret = valid0;
4494 /* Support narrowing pointer differences. */
4495 else
4496 ret = narrowing_initializer_constant_valid_p (value, endtype,
4497 ncache);
4499 else
4500 /* Support narrowing pointer differences. */
4501 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4502 if (cache)
4504 cache[0] = value;
4505 cache[1] = ret;
4507 return ret;
4509 case MINUS_EXPR:
4510 if (TREE_CODE (endtype) == REAL_TYPE)
4511 return NULL_TREE;
4512 if (cache && cache[0] == value)
4513 return cache[1];
4514 if (! INTEGRAL_TYPE_P (endtype)
4515 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4517 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4518 tree valid0
4519 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4520 endtype, ncache);
4521 tree valid1
4522 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4523 endtype, ncache + 2);
4524 /* Win if second argument is absolute. */
4525 if (valid1 == null_pointer_node)
4526 ret = valid0;
4527 /* Win if both arguments have the same relocation.
4528 Then the value is absolute. */
4529 else if (valid0 == valid1 && valid0 != 0)
4530 ret = null_pointer_node;
4531 /* Since GCC guarantees that string constants are unique in the
4532 generated code, a subtraction between two copies of the same
4533 constant string is absolute. */
4534 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4535 && valid1 && TREE_CODE (valid1) == STRING_CST
4536 && operand_equal_p (valid0, valid1, 1))
4537 ret = null_pointer_node;
4538 /* Support narrowing differences. */
4539 else
4540 ret = narrowing_initializer_constant_valid_p (value, endtype,
4541 ncache);
4543 else
4544 /* Support narrowing differences. */
4545 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4546 if (cache)
4548 cache[0] = value;
4549 cache[1] = ret;
4551 return ret;
4553 default:
4554 break;
4557 return NULL_TREE;
4560 /* Return nonzero if VALUE is a valid constant-valued expression
4561 for use in initializing a static variable; one that can be an
4562 element of a "constant" initializer.
4564 Return null_pointer_node if the value is absolute;
4565 if it is relocatable, return the variable that determines the relocation.
4566 We assume that VALUE has been folded as much as possible;
4567 therefore, we do not need to check for such things as
4568 arithmetic-combinations of integers. */
4569 tree
4570 initializer_constant_valid_p (tree value, tree endtype, bool reverse)
4572 tree reloc = initializer_constant_valid_p_1 (value, endtype, NULL);
4574 /* An absolute value is required with reverse storage order. */
4575 if (reloc
4576 && reloc != null_pointer_node
4577 && reverse
4578 && !AGGREGATE_TYPE_P (endtype)
4579 && !VECTOR_TYPE_P (endtype))
4580 reloc = NULL_TREE;
4582 return reloc;
4585 /* Return true if VALUE is a valid constant-valued expression
4586 for use in initializing a static bit-field; one that can be
4587 an element of a "constant" initializer. */
4589 bool
4590 initializer_constant_valid_for_bitfield_p (tree value)
4592 /* For bitfields we support integer constants or possibly nested aggregates
4593 of such. */
4594 switch (TREE_CODE (value))
4596 case CONSTRUCTOR:
4598 unsigned HOST_WIDE_INT idx;
4599 tree elt;
4601 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4602 if (!initializer_constant_valid_for_bitfield_p (elt))
4603 return false;
4604 return true;
4607 case INTEGER_CST:
4608 case REAL_CST:
4609 return true;
4611 case VIEW_CONVERT_EXPR:
4612 case NON_LVALUE_EXPR:
4613 return
4614 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4616 default:
4617 break;
4620 return false;
4623 /* output_constructor outer state of relevance in recursive calls, typically
4624 for nested aggregate bitfields. */
4626 struct oc_outer_state {
4627 unsigned int bit_offset; /* current position in ... */
4628 int byte; /* ... the outer byte buffer. */
4631 static unsigned HOST_WIDE_INT
4632 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int, bool,
4633 oc_outer_state *);
4635 /* Output assembler code for constant EXP, with no label.
4636 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4637 Assumes output_addressed_constants has been done on EXP already.
4639 Generate at least SIZE bytes of assembler data, padding at the end
4640 with zeros if necessary. SIZE must always be specified. The returned
4641 value is the actual number of bytes of assembler data generated, which
4642 may be bigger than SIZE if the object contains a variable length field.
4644 SIZE is important for structure constructors,
4645 since trailing members may have been omitted from the constructor.
4646 It is also important for initialization of arrays from string constants
4647 since the full length of the string constant might not be wanted.
4648 It is also needed for initialization of unions, where the initializer's
4649 type is just one member, and that may not be as long as the union.
4651 There a case in which we would fail to output exactly SIZE bytes:
4652 for a structure constructor that wants to produce more than SIZE bytes.
4653 But such constructors will never be generated for any possible input.
4655 ALIGN is the alignment of the data in bits.
4657 If REVERSE is true, EXP is output in reverse storage order. */
4659 static unsigned HOST_WIDE_INT
4660 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align,
4661 bool reverse)
4663 enum tree_code code;
4664 unsigned HOST_WIDE_INT thissize;
4665 rtx cst;
4667 if (size == 0 || flag_syntax_only)
4668 return size;
4670 /* See if we're trying to initialize a pointer in a non-default mode
4671 to the address of some declaration somewhere. If the target says
4672 the mode is valid for pointers, assume the target has a way of
4673 resolving it. */
4674 if (TREE_CODE (exp) == NOP_EXPR
4675 && POINTER_TYPE_P (TREE_TYPE (exp))
4676 && targetm.addr_space.valid_pointer_mode
4677 (TYPE_MODE (TREE_TYPE (exp)),
4678 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4680 tree saved_type = TREE_TYPE (exp);
4682 /* Peel off any intermediate conversions-to-pointer for valid
4683 pointer modes. */
4684 while (TREE_CODE (exp) == NOP_EXPR
4685 && POINTER_TYPE_P (TREE_TYPE (exp))
4686 && targetm.addr_space.valid_pointer_mode
4687 (TYPE_MODE (TREE_TYPE (exp)),
4688 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4689 exp = TREE_OPERAND (exp, 0);
4691 /* If what we're left with is the address of something, we can
4692 convert the address to the final type and output it that
4693 way. */
4694 if (TREE_CODE (exp) == ADDR_EXPR)
4695 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4696 /* Likewise for constant ints. */
4697 else if (TREE_CODE (exp) == INTEGER_CST)
4698 exp = fold_convert (saved_type, exp);
4702 /* Eliminate any conversions since we'll be outputting the underlying
4703 constant. */
4704 while (CONVERT_EXPR_P (exp)
4705 || TREE_CODE (exp) == NON_LVALUE_EXPR
4706 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4708 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4709 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4711 /* Make sure eliminating the conversion is really a no-op, except with
4712 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4713 union types to allow for Ada unchecked unions. */
4714 if (type_size > op_size
4715 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4716 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4717 /* Keep the conversion. */
4718 break;
4719 else
4720 exp = TREE_OPERAND (exp, 0);
4723 code = TREE_CODE (TREE_TYPE (exp));
4724 thissize = int_size_in_bytes (TREE_TYPE (exp));
4726 /* Allow a constructor with no elements for any data type.
4727 This means to fill the space with zeros. */
4728 if (TREE_CODE (exp) == CONSTRUCTOR
4729 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4731 assemble_zeros (size);
4732 return size;
4735 if (TREE_CODE (exp) == FDESC_EXPR)
4737 #ifdef ASM_OUTPUT_FDESC
4738 HOST_WIDE_INT part = tree_to_shwi (TREE_OPERAND (exp, 1));
4739 tree decl = TREE_OPERAND (exp, 0);
4740 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4741 #else
4742 gcc_unreachable ();
4743 #endif
4744 return size;
4747 /* Now output the underlying data. If we've handling the padding, return.
4748 Otherwise, break and ensure SIZE is the size written. */
4749 switch (code)
4751 case BOOLEAN_TYPE:
4752 case INTEGER_TYPE:
4753 case ENUMERAL_TYPE:
4754 case POINTER_TYPE:
4755 case REFERENCE_TYPE:
4756 case OFFSET_TYPE:
4757 case FIXED_POINT_TYPE:
4758 case POINTER_BOUNDS_TYPE:
4759 case NULLPTR_TYPE:
4760 cst = expand_expr (exp, NULL_RTX, VOIDmode, EXPAND_INITIALIZER);
4761 if (reverse)
4762 cst = flip_storage_order (TYPE_MODE (TREE_TYPE (exp)), cst);
4763 if (!assemble_integer (cst, MIN (size, thissize), align, 0))
4764 error ("initializer for integer/fixed-point value is too complicated");
4765 break;
4767 case REAL_TYPE:
4768 if (TREE_CODE (exp) != REAL_CST)
4769 error ("initializer for floating value is not a floating constant");
4770 else
4771 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)),
4772 align, reverse);
4773 break;
4775 case COMPLEX_TYPE:
4776 output_constant (TREE_REALPART (exp), thissize / 2, align, reverse);
4777 output_constant (TREE_IMAGPART (exp), thissize / 2,
4778 min_align (align, BITS_PER_UNIT * (thissize / 2)),
4779 reverse);
4780 break;
4782 case ARRAY_TYPE:
4783 case VECTOR_TYPE:
4784 switch (TREE_CODE (exp))
4786 case CONSTRUCTOR:
4787 return output_constructor (exp, size, align, reverse, NULL);
4788 case STRING_CST:
4789 thissize
4790 = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4791 assemble_string (TREE_STRING_POINTER (exp), thissize);
4792 break;
4793 case VECTOR_CST:
4795 machine_mode inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4796 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4797 int elt_size = GET_MODE_SIZE (inner);
4798 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align,
4799 reverse);
4800 thissize = elt_size;
4801 for (unsigned int i = 1; i < VECTOR_CST_NELTS (exp); i++)
4803 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign,
4804 reverse);
4805 thissize += elt_size;
4807 break;
4809 default:
4810 gcc_unreachable ();
4812 break;
4814 case RECORD_TYPE:
4815 case UNION_TYPE:
4816 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4817 return output_constructor (exp, size, align, reverse, NULL);
4819 case ERROR_MARK:
4820 return 0;
4822 default:
4823 gcc_unreachable ();
4826 if (size > thissize)
4827 assemble_zeros (size - thissize);
4829 return size;
4832 /* Subroutine of output_constructor, used for computing the size of
4833 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4834 type with an unspecified upper bound. */
4836 static unsigned HOST_WIDE_INT
4837 array_size_for_constructor (tree val)
4839 tree max_index;
4840 unsigned HOST_WIDE_INT cnt;
4841 tree index, value, tmp;
4842 offset_int i;
4844 /* This code used to attempt to handle string constants that are not
4845 arrays of single-bytes, but nothing else does, so there's no point in
4846 doing it here. */
4847 if (TREE_CODE (val) == STRING_CST)
4848 return TREE_STRING_LENGTH (val);
4850 max_index = NULL_TREE;
4851 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
4853 if (TREE_CODE (index) == RANGE_EXPR)
4854 index = TREE_OPERAND (index, 1);
4855 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
4856 max_index = index;
4859 if (max_index == NULL_TREE)
4860 return 0;
4862 /* Compute the total number of array elements. */
4863 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
4864 i = wi::to_offset (max_index) - wi::to_offset (tmp) + 1;
4866 /* Multiply by the array element unit size to find number of bytes. */
4867 i *= wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
4869 gcc_assert (wi::fits_uhwi_p (i));
4870 return i.to_uhwi ();
4873 /* Other datastructures + helpers for output_constructor. */
4875 /* output_constructor local state to support interaction with helpers. */
4877 struct oc_local_state {
4879 /* Received arguments. */
4880 tree exp; /* Constructor expression. */
4881 tree type; /* Type of constructor expression. */
4882 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */
4883 unsigned int align; /* Known initial alignment. */
4884 tree min_index; /* Lower bound if specified for an array. */
4886 /* Output processing state. */
4887 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */
4888 int byte; /* Part of a bitfield byte yet to be output. */
4889 int last_relative_index; /* Implicit or explicit index of the last
4890 array element output within a bitfield. */
4891 bool byte_buffer_in_use; /* Whether BYTE is in use. */
4892 bool reverse; /* Whether reverse storage order is in use. */
4894 /* Current element. */
4895 tree field; /* Current field decl in a record. */
4896 tree val; /* Current element value. */
4897 tree index; /* Current element index. */
4901 /* Helper for output_constructor. From the current LOCAL state, output a
4902 RANGE_EXPR element. */
4904 static void
4905 output_constructor_array_range (oc_local_state *local)
4907 unsigned HOST_WIDE_INT fieldsize
4908 = int_size_in_bytes (TREE_TYPE (local->type));
4910 HOST_WIDE_INT lo_index
4911 = tree_to_shwi (TREE_OPERAND (local->index, 0));
4912 HOST_WIDE_INT hi_index
4913 = tree_to_shwi (TREE_OPERAND (local->index, 1));
4914 HOST_WIDE_INT index;
4916 unsigned int align2
4917 = min_align (local->align, fieldsize * BITS_PER_UNIT);
4919 for (index = lo_index; index <= hi_index; index++)
4921 /* Output the element's initial value. */
4922 if (local->val == NULL_TREE)
4923 assemble_zeros (fieldsize);
4924 else
4925 fieldsize
4926 = output_constant (local->val, fieldsize, align2, local->reverse);
4928 /* Count its size. */
4929 local->total_bytes += fieldsize;
4933 /* Helper for output_constructor. From the current LOCAL state, output a
4934 field element that is not true bitfield or part of an outer one. */
4936 static void
4937 output_constructor_regular_field (oc_local_state *local)
4939 /* Field size and position. Since this structure is static, we know the
4940 positions are constant. */
4941 unsigned HOST_WIDE_INT fieldsize;
4942 HOST_WIDE_INT fieldpos;
4944 unsigned int align2;
4946 /* Output any buffered-up bit-fields preceding this element. */
4947 if (local->byte_buffer_in_use)
4949 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4950 local->total_bytes++;
4951 local->byte_buffer_in_use = false;
4954 if (local->index != NULL_TREE)
4956 /* Perform the index calculation in modulo arithmetic but
4957 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
4958 but we are using an unsigned sizetype. */
4959 unsigned prec = TYPE_PRECISION (sizetype);
4960 offset_int idx = wi::sext (wi::to_offset (local->index)
4961 - wi::to_offset (local->min_index), prec);
4962 fieldpos = (idx * wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (local->val))))
4963 .to_short_addr ();
4965 else if (local->field != NULL_TREE)
4966 fieldpos = int_byte_position (local->field);
4967 else
4968 fieldpos = 0;
4970 /* Advance to offset of this element.
4971 Note no alignment needed in an array, since that is guaranteed
4972 if each element has the proper size. */
4973 if (local->field != NULL_TREE || local->index != NULL_TREE)
4975 if (fieldpos > local->total_bytes)
4977 assemble_zeros (fieldpos - local->total_bytes);
4978 local->total_bytes = fieldpos;
4980 else
4981 /* Must not go backwards. */
4982 gcc_assert (fieldpos == local->total_bytes);
4985 /* Find the alignment of this element. */
4986 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
4988 /* Determine size this element should occupy. */
4989 if (local->field)
4991 fieldsize = 0;
4993 /* If this is an array with an unspecified upper bound,
4994 the initializer determines the size. */
4995 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
4996 but we cannot do this until the deprecated support for
4997 initializing zero-length array members is removed. */
4998 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
4999 && (!TYPE_DOMAIN (TREE_TYPE (local->field))
5000 || !TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field)))))
5002 fieldsize = array_size_for_constructor (local->val);
5003 /* Given a non-empty initialization, this field had better
5004 be last. Given a flexible array member, the next field
5005 on the chain is a TYPE_DECL of the enclosing struct. */
5006 const_tree next = DECL_CHAIN (local->field);
5007 gcc_assert (!fieldsize || !next || TREE_CODE (next) != FIELD_DECL);
5009 else
5010 fieldsize = tree_to_uhwi (DECL_SIZE_UNIT (local->field));
5012 else
5013 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
5015 /* Output the element's initial value. */
5016 if (local->val == NULL_TREE)
5017 assemble_zeros (fieldsize);
5018 else
5019 fieldsize
5020 = output_constant (local->val, fieldsize, align2, local->reverse);
5022 /* Count its size. */
5023 local->total_bytes += fieldsize;
5026 /* Helper for output_constructor. From the LOCAL state, output an element
5027 that is a true bitfield or part of an outer one. BIT_OFFSET is the offset
5028 from the start of a possibly ongoing outer byte buffer. */
5030 static void
5031 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
5033 /* Bit size of this element. */
5034 HOST_WIDE_INT ebitsize
5035 = (local->field
5036 ? tree_to_uhwi (DECL_SIZE (local->field))
5037 : tree_to_uhwi (TYPE_SIZE (TREE_TYPE (local->type))));
5039 /* Relative index of this element if this is an array component. */
5040 HOST_WIDE_INT relative_index
5041 = (!local->field
5042 ? (local->index
5043 ? (tree_to_shwi (local->index)
5044 - tree_to_shwi (local->min_index))
5045 : local->last_relative_index + 1)
5046 : 0);
5048 /* Bit position of this element from the start of the containing
5049 constructor. */
5050 HOST_WIDE_INT constructor_relative_ebitpos
5051 = (local->field
5052 ? int_bit_position (local->field)
5053 : ebitsize * relative_index);
5055 /* Bit position of this element from the start of a possibly ongoing
5056 outer byte buffer. */
5057 HOST_WIDE_INT byte_relative_ebitpos
5058 = bit_offset + constructor_relative_ebitpos;
5060 /* From the start of a possibly ongoing outer byte buffer, offsets to
5061 the first bit of this element and to the first bit past the end of
5062 this element. */
5063 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
5064 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
5066 local->last_relative_index = relative_index;
5068 if (local->val == NULL_TREE)
5069 local->val = integer_zero_node;
5071 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
5072 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
5073 local->val = TREE_OPERAND (local->val, 0);
5075 if (TREE_CODE (local->val) != INTEGER_CST
5076 && TREE_CODE (local->val) != CONSTRUCTOR)
5078 error ("invalid initial value for member %qE", DECL_NAME (local->field));
5079 return;
5082 /* If this field does not start in this (or next) byte, skip some bytes. */
5083 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5085 /* Output remnant of any bit field in previous bytes. */
5086 if (local->byte_buffer_in_use)
5088 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5089 local->total_bytes++;
5090 local->byte_buffer_in_use = false;
5093 /* If still not at proper byte, advance to there. */
5094 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5096 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
5097 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
5098 local->total_bytes = next_offset / BITS_PER_UNIT;
5102 /* Set up the buffer if necessary. */
5103 if (!local->byte_buffer_in_use)
5105 local->byte = 0;
5106 if (ebitsize > 0)
5107 local->byte_buffer_in_use = true;
5110 /* If this is nested constructor, recurse passing the bit offset and the
5111 pending data, then retrieve the new pending data afterwards. */
5112 if (TREE_CODE (local->val) == CONSTRUCTOR)
5114 oc_outer_state temp_state;
5115 temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5116 temp_state.byte = local->byte;
5117 local->total_bytes
5118 += output_constructor (local->val, 0, 0, local->reverse, &temp_state);
5119 local->byte = temp_state.byte;
5120 return;
5123 /* Otherwise, we must split the element into pieces that fall within
5124 separate bytes, and combine each byte with previous or following
5125 bit-fields. */
5126 while (next_offset < end_offset)
5128 int this_time;
5129 int shift;
5130 HOST_WIDE_INT value;
5131 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5132 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5134 /* Advance from byte to byte within this element when necessary. */
5135 while (next_byte != local->total_bytes)
5137 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5138 local->total_bytes++;
5139 local->byte = 0;
5142 /* Number of bits we can process at once (all part of the same byte). */
5143 this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5144 if (local->reverse ? !BYTES_BIG_ENDIAN : BYTES_BIG_ENDIAN)
5146 /* For big-endian data, take the most significant bits (of the
5147 bits that are significant) first and put them into bytes from
5148 the most significant end. */
5149 shift = end_offset - next_offset - this_time;
5151 /* Don't try to take a bunch of bits that cross
5152 the word boundary in the INTEGER_CST. We can
5153 only select bits from one element. */
5154 if ((shift / HOST_BITS_PER_WIDE_INT)
5155 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5157 const int end = shift + this_time - 1;
5158 shift = end & -HOST_BITS_PER_WIDE_INT;
5159 this_time = end - shift + 1;
5162 /* Now get the bits from the appropriate constant word. */
5163 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5164 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5166 /* Get the result. This works only when:
5167 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5168 local->byte |= (((value >> shift)
5169 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5170 << (BITS_PER_UNIT - this_time - next_bit));
5172 else
5174 /* On little-endian machines, take the least significant bits of
5175 the value first and pack them starting at the least significant
5176 bits of the bytes. */
5177 shift = next_offset - byte_relative_ebitpos;
5179 /* Don't try to take a bunch of bits that cross
5180 the word boundary in the INTEGER_CST. We can
5181 only select bits from one element. */
5182 if ((shift / HOST_BITS_PER_WIDE_INT)
5183 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5184 this_time
5185 = HOST_BITS_PER_WIDE_INT - (shift & (HOST_BITS_PER_WIDE_INT - 1));
5187 /* Now get the bits from the appropriate constant word. */
5188 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5189 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5191 /* Get the result. This works only when:
5192 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5193 local->byte |= (((value >> shift)
5194 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5195 << next_bit);
5198 next_offset += this_time;
5199 local->byte_buffer_in_use = true;
5203 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5204 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5205 caller output state of relevance in recursive invocations. */
5207 static unsigned HOST_WIDE_INT
5208 output_constructor (tree exp, unsigned HOST_WIDE_INT size, unsigned int align,
5209 bool reverse, oc_outer_state *outer)
5211 unsigned HOST_WIDE_INT cnt;
5212 constructor_elt *ce;
5213 oc_local_state local;
5215 /* Setup our local state to communicate with helpers. */
5216 local.exp = exp;
5217 local.type = TREE_TYPE (exp);
5218 local.size = size;
5219 local.align = align;
5220 if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5221 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5222 else
5223 local.min_index = integer_zero_node;
5225 local.total_bytes = 0;
5226 local.byte_buffer_in_use = outer != NULL;
5227 local.byte = outer ? outer->byte : 0;
5228 local.last_relative_index = -1;
5229 /* The storage order is specified for every aggregate type. */
5230 if (AGGREGATE_TYPE_P (local.type))
5231 local.reverse = TYPE_REVERSE_STORAGE_ORDER (local.type);
5232 else
5233 local.reverse = reverse;
5235 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5237 /* As CE goes through the elements of the constant, FIELD goes through the
5238 structure fields if the constant is a structure. If the constant is a
5239 union, we override this by getting the field from the TREE_LIST element.
5240 But the constant could also be an array. Then FIELD is zero.
5242 There is always a maximum of one element in the chain LINK for unions
5243 (even if the initializer in a source program incorrectly contains
5244 more one). */
5246 if (TREE_CODE (local.type) == RECORD_TYPE)
5247 local.field = TYPE_FIELDS (local.type);
5248 else
5249 local.field = NULL_TREE;
5251 for (cnt = 0;
5252 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5253 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5255 local.val = ce->value;
5256 local.index = NULL_TREE;
5258 /* The element in a union constructor specifies the proper field
5259 or index. */
5260 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5261 local.field = ce->index;
5263 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5264 local.index = ce->index;
5266 if (local.field && flag_verbose_asm)
5267 fprintf (asm_out_file, "%s %s:\n",
5268 ASM_COMMENT_START,
5269 DECL_NAME (local.field)
5270 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5271 : "<anonymous>");
5273 /* Eliminate the marker that makes a cast not be an lvalue. */
5274 if (local.val != NULL_TREE)
5275 STRIP_NOPS (local.val);
5277 /* Output the current element, using the appropriate helper ... */
5279 /* For an array slice not part of an outer bitfield. */
5280 if (!outer
5281 && local.index != NULL_TREE
5282 && TREE_CODE (local.index) == RANGE_EXPR)
5283 output_constructor_array_range (&local);
5285 /* For a field that is neither a true bitfield nor part of an outer one,
5286 known to be at least byte aligned and multiple-of-bytes long. */
5287 else if (!outer
5288 && (local.field == NULL_TREE
5289 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5290 output_constructor_regular_field (&local);
5292 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5293 supported for scalar fields, so we may need to convert first. */
5294 else
5296 if (TREE_CODE (local.val) == REAL_CST)
5297 local.val
5298 = fold_unary (VIEW_CONVERT_EXPR,
5299 build_nonstandard_integer_type
5300 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5301 local.val);
5302 output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5306 /* If we are not at toplevel, save the pending data for our caller.
5307 Otherwise output the pending data and padding zeros as needed. */
5308 if (outer)
5309 outer->byte = local.byte;
5310 else
5312 if (local.byte_buffer_in_use)
5314 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5315 local.total_bytes++;
5318 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5320 assemble_zeros (local.size - local.total_bytes);
5321 local.total_bytes = local.size;
5325 return local.total_bytes;
5328 /* Mark DECL as weak. */
5330 static void
5331 mark_weak (tree decl)
5333 if (DECL_WEAK (decl))
5334 return;
5336 struct symtab_node *n = symtab_node::get (decl);
5337 if (n && n->refuse_visibility_changes)
5338 error ("%+D declared weak after being used", decl);
5339 DECL_WEAK (decl) = 1;
5341 if (DECL_RTL_SET_P (decl)
5342 && MEM_P (DECL_RTL (decl))
5343 && XEXP (DECL_RTL (decl), 0)
5344 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5345 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5348 /* Merge weak status between NEWDECL and OLDDECL. */
5350 void
5351 merge_weak (tree newdecl, tree olddecl)
5353 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5355 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5357 tree *pwd;
5358 /* We put the NEWDECL on the weak_decls list at some point
5359 and OLDDECL as well. Keep just OLDDECL on the list. */
5360 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5361 if (TREE_VALUE (*pwd) == newdecl)
5363 *pwd = TREE_CHAIN (*pwd);
5364 break;
5367 return;
5370 if (DECL_WEAK (newdecl))
5372 tree wd;
5374 /* NEWDECL is weak, but OLDDECL is not. */
5376 /* If we already output the OLDDECL, we're in trouble; we can't
5377 go back and make it weak. This should never happen in
5378 unit-at-a-time compilation. */
5379 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5381 /* If we've already generated rtl referencing OLDDECL, we may
5382 have done so in a way that will not function properly with
5383 a weak symbol. Again in unit-at-a-time this should be
5384 impossible. */
5385 gcc_assert (!TREE_USED (olddecl)
5386 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5388 /* PR 49899: You cannot convert a static function into a weak, public function. */
5389 if (! TREE_PUBLIC (olddecl) && TREE_PUBLIC (newdecl))
5390 error ("weak declaration of %q+D being applied to a already "
5391 "existing, static definition", newdecl);
5393 if (TARGET_SUPPORTS_WEAK)
5395 /* We put the NEWDECL on the weak_decls list at some point.
5396 Replace it with the OLDDECL. */
5397 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5398 if (TREE_VALUE (wd) == newdecl)
5400 TREE_VALUE (wd) = olddecl;
5401 break;
5403 /* We may not find the entry on the list. If NEWDECL is a
5404 weak alias, then we will have already called
5405 globalize_decl to remove the entry; in that case, we do
5406 not need to do anything. */
5409 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5410 mark_weak (olddecl);
5412 else
5413 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5414 weak. Just update NEWDECL to indicate that it's weak too. */
5415 mark_weak (newdecl);
5418 /* Declare DECL to be a weak symbol. */
5420 void
5421 declare_weak (tree decl)
5423 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5424 if (! TREE_PUBLIC (decl))
5426 error ("weak declaration of %q+D must be public", decl);
5427 return;
5429 else if (!TARGET_SUPPORTS_WEAK)
5430 warning (0, "weak declaration of %q+D not supported", decl);
5432 mark_weak (decl);
5433 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5434 DECL_ATTRIBUTES (decl)
5435 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5438 static void
5439 weak_finish_1 (tree decl)
5441 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5442 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5443 #endif
5445 if (! TREE_USED (decl))
5446 return;
5448 #ifdef ASM_WEAKEN_DECL
5449 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5450 #else
5451 #ifdef ASM_WEAKEN_LABEL
5452 ASM_WEAKEN_LABEL (asm_out_file, name);
5453 #else
5454 #ifdef ASM_OUTPUT_WEAK_ALIAS
5456 static bool warn_once = 0;
5457 if (! warn_once)
5459 warning (0, "only weak aliases are supported in this configuration");
5460 warn_once = 1;
5462 return;
5464 #endif
5465 #endif
5466 #endif
5469 /* Fiven an assembly name, find the decl it is associated with. */
5470 static tree
5471 find_decl (tree target)
5473 symtab_node *node = symtab_node::get_for_asmname (target);
5474 if (node)
5475 return node->decl;
5476 return NULL_TREE;
5479 /* This TREE_LIST contains weakref targets. */
5481 static GTY(()) tree weakref_targets;
5483 /* Emit any pending weak declarations. */
5485 void
5486 weak_finish (void)
5488 tree t;
5490 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5492 tree alias_decl = TREE_PURPOSE (t);
5493 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5495 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5496 /* Remove alias_decl from the weak list, but leave entries for
5497 the target alone. */
5498 target = NULL_TREE;
5499 #ifndef ASM_OUTPUT_WEAKREF
5500 else if (! TREE_SYMBOL_REFERENCED (target))
5502 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5503 defined, otherwise we and weak_finish_1 would use
5504 different macros. */
5505 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5506 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5507 # else
5508 tree decl = find_decl (target);
5510 if (! decl)
5512 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5513 TREE_CODE (alias_decl), target,
5514 TREE_TYPE (alias_decl));
5516 DECL_EXTERNAL (decl) = 1;
5517 TREE_PUBLIC (decl) = 1;
5518 DECL_ARTIFICIAL (decl) = 1;
5519 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5520 TREE_USED (decl) = 1;
5523 weak_finish_1 (decl);
5524 # endif
5526 #endif
5529 tree *p;
5530 tree t2;
5532 /* Remove the alias and the target from the pending weak list
5533 so that we do not emit any .weak directives for the former,
5534 nor multiple .weak directives for the latter. */
5535 for (p = &weak_decls; (t2 = *p) ; )
5537 if (TREE_VALUE (t2) == alias_decl
5538 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5539 *p = TREE_CHAIN (t2);
5540 else
5541 p = &TREE_CHAIN (t2);
5544 /* Remove other weakrefs to the same target, to speed things up. */
5545 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5547 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5548 *p = TREE_CHAIN (t2);
5549 else
5550 p = &TREE_CHAIN (t2);
5555 for (t = weak_decls; t; t = TREE_CHAIN (t))
5557 tree decl = TREE_VALUE (t);
5559 weak_finish_1 (decl);
5563 /* Emit the assembly bits to indicate that DECL is globally visible. */
5565 static void
5566 globalize_decl (tree decl)
5569 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5570 if (DECL_WEAK (decl))
5572 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5573 tree *p, t;
5575 #ifdef ASM_WEAKEN_DECL
5576 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5577 #else
5578 ASM_WEAKEN_LABEL (asm_out_file, name);
5579 #endif
5581 /* Remove this function from the pending weak list so that
5582 we do not emit multiple .weak directives for it. */
5583 for (p = &weak_decls; (t = *p) ; )
5585 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5586 *p = TREE_CHAIN (t);
5587 else
5588 p = &TREE_CHAIN (t);
5591 /* Remove weakrefs to the same target from the pending weakref
5592 list, for the same reason. */
5593 for (p = &weakref_targets; (t = *p) ; )
5595 if (DECL_ASSEMBLER_NAME (decl)
5596 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5597 *p = TREE_CHAIN (t);
5598 else
5599 p = &TREE_CHAIN (t);
5602 return;
5604 #endif
5606 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5609 vec<alias_pair, va_gc> *alias_pairs;
5611 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5612 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5613 tree node is DECL to have the value of the tree node TARGET. */
5615 void
5616 do_assemble_alias (tree decl, tree target)
5618 tree id;
5620 /* Emulated TLS had better not get this var. */
5621 gcc_assert (!(!targetm.have_tls
5622 && VAR_P (decl)
5623 && DECL_THREAD_LOCAL_P (decl)));
5625 if (TREE_ASM_WRITTEN (decl))
5626 return;
5628 id = DECL_ASSEMBLER_NAME (decl);
5629 ultimate_transparent_alias_target (&id);
5630 ultimate_transparent_alias_target (&target);
5632 /* We must force creation of DECL_RTL for debug info generation, even though
5633 we don't use it here. */
5634 make_decl_rtl (decl);
5636 TREE_ASM_WRITTEN (decl) = 1;
5637 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5638 TREE_ASM_WRITTEN (id) = 1;
5640 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5642 if (!TREE_SYMBOL_REFERENCED (target))
5643 weakref_targets = tree_cons (decl, target, weakref_targets);
5645 #ifdef ASM_OUTPUT_WEAKREF
5646 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5647 IDENTIFIER_POINTER (id),
5648 IDENTIFIER_POINTER (target));
5649 #else
5650 if (!TARGET_SUPPORTS_WEAK)
5652 error_at (DECL_SOURCE_LOCATION (decl),
5653 "weakref is not supported in this configuration");
5654 return;
5656 #endif
5657 return;
5660 #ifdef ASM_OUTPUT_DEF
5661 tree orig_decl = decl;
5663 if (TREE_CODE (decl) == FUNCTION_DECL
5664 && cgraph_node::get (decl)->instrumentation_clone
5665 && cgraph_node::get (decl)->instrumented_version)
5666 orig_decl = cgraph_node::get (decl)->instrumented_version->decl;
5668 /* Make name accessible from other files, if appropriate. */
5670 if (TREE_PUBLIC (decl) || TREE_PUBLIC (orig_decl))
5672 globalize_decl (decl);
5673 maybe_assemble_visibility (decl);
5675 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5677 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5678 if (targetm.has_ifunc_p ())
5679 ASM_OUTPUT_TYPE_DIRECTIVE
5680 (asm_out_file, IDENTIFIER_POINTER (id),
5681 IFUNC_ASM_TYPE);
5682 else
5683 #endif
5684 error_at (DECL_SOURCE_LOCATION (decl),
5685 "ifunc is not supported on this target");
5688 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5689 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5690 # else
5691 ASM_OUTPUT_DEF (asm_out_file,
5692 IDENTIFIER_POINTER (id),
5693 IDENTIFIER_POINTER (target));
5694 # endif
5695 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5697 const char *name;
5698 tree *p, t;
5700 name = IDENTIFIER_POINTER (id);
5701 # ifdef ASM_WEAKEN_DECL
5702 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5703 # else
5704 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5705 # endif
5706 /* Remove this function from the pending weak list so that
5707 we do not emit multiple .weak directives for it. */
5708 for (p = &weak_decls; (t = *p) ; )
5709 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t))
5710 || id == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5711 *p = TREE_CHAIN (t);
5712 else
5713 p = &TREE_CHAIN (t);
5715 /* Remove weakrefs to the same target from the pending weakref
5716 list, for the same reason. */
5717 for (p = &weakref_targets; (t = *p) ; )
5719 if (id == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5720 *p = TREE_CHAIN (t);
5721 else
5722 p = &TREE_CHAIN (t);
5725 #endif
5728 /* Emit an assembler directive to make the symbol for DECL an alias to
5729 the symbol for TARGET. */
5731 void
5732 assemble_alias (tree decl, tree target)
5734 tree target_decl;
5736 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5738 tree alias = DECL_ASSEMBLER_NAME (decl);
5740 ultimate_transparent_alias_target (&target);
5742 if (alias == target)
5743 error ("weakref %q+D ultimately targets itself", decl);
5744 if (TREE_PUBLIC (decl))
5745 error ("weakref %q+D must have static linkage", decl);
5747 else
5749 #if !defined (ASM_OUTPUT_DEF)
5750 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5751 error_at (DECL_SOURCE_LOCATION (decl),
5752 "alias definitions not supported in this configuration");
5753 TREE_ASM_WRITTEN (decl) = 1;
5754 return;
5755 # else
5756 if (!DECL_WEAK (decl))
5758 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5759 error_at (DECL_SOURCE_LOCATION (decl),
5760 "ifunc is not supported in this configuration");
5761 else
5762 error_at (DECL_SOURCE_LOCATION (decl),
5763 "only weak aliases are supported in this configuration");
5764 TREE_ASM_WRITTEN (decl) = 1;
5765 return;
5767 # endif
5768 #endif
5770 TREE_USED (decl) = 1;
5772 /* Allow aliases to aliases. */
5773 if (TREE_CODE (decl) == FUNCTION_DECL)
5774 cgraph_node::get_create (decl)->alias = true;
5775 else
5776 varpool_node::get_create (decl)->alias = true;
5778 /* If the target has already been emitted, we don't have to queue the
5779 alias. This saves a tad of memory. */
5780 if (symtab->global_info_ready)
5781 target_decl = find_decl (target);
5782 else
5783 target_decl= NULL;
5784 if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5785 || symtab->state >= EXPANSION)
5786 do_assemble_alias (decl, target);
5787 else
5789 alias_pair p = {decl, target};
5790 vec_safe_push (alias_pairs, p);
5794 /* Record and output a table of translations from original function
5795 to its transaction aware clone. Note that tm_pure functions are
5796 considered to be their own clone. */
5798 struct tm_clone_hasher : ggc_cache_ptr_hash<tree_map>
5800 static hashval_t hash (tree_map *m) { return tree_map_hash (m); }
5801 static bool equal (tree_map *a, tree_map *b) { return tree_map_eq (a, b); }
5803 static int
5804 keep_cache_entry (tree_map *&e)
5806 return ggc_marked_p (e->base.from);
5810 static GTY((cache)) hash_table<tm_clone_hasher> *tm_clone_hash;
5812 void
5813 record_tm_clone_pair (tree o, tree n)
5815 struct tree_map **slot, *h;
5817 if (tm_clone_hash == NULL)
5818 tm_clone_hash = hash_table<tm_clone_hasher>::create_ggc (32);
5820 h = ggc_alloc<tree_map> ();
5821 h->hash = htab_hash_pointer (o);
5822 h->base.from = o;
5823 h->to = n;
5825 slot = tm_clone_hash->find_slot_with_hash (h, h->hash, INSERT);
5826 *slot = h;
5829 tree
5830 get_tm_clone_pair (tree o)
5832 if (tm_clone_hash)
5834 struct tree_map *h, in;
5836 in.base.from = o;
5837 in.hash = htab_hash_pointer (o);
5838 h = tm_clone_hash->find_with_hash (&in, in.hash);
5839 if (h)
5840 return h->to;
5842 return NULL_TREE;
5845 struct tm_alias_pair
5847 unsigned int uid;
5848 tree from;
5849 tree to;
5853 /* Dump the actual pairs to the .tm_clone_table section. */
5855 static void
5856 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
5858 unsigned i;
5859 tm_alias_pair *p;
5860 bool switched = false;
5862 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
5864 tree src = p->from;
5865 tree dst = p->to;
5866 struct cgraph_node *src_n = cgraph_node::get (src);
5867 struct cgraph_node *dst_n = cgraph_node::get (dst);
5869 /* The function ipa_tm_create_version() marks the clone as needed if
5870 the original function was needed. But we also mark the clone as
5871 needed if we ever called the clone indirectly through
5872 TM_GETTMCLONE. If neither of these are true, we didn't generate
5873 a clone, and we didn't call it indirectly... no sense keeping it
5874 in the clone table. */
5875 if (!dst_n || !dst_n->definition)
5876 continue;
5878 /* This covers the case where we have optimized the original
5879 function away, and only access the transactional clone. */
5880 if (!src_n || !src_n->definition)
5881 continue;
5883 if (!switched)
5885 switch_to_section (targetm.asm_out.tm_clone_table_section ());
5886 assemble_align (POINTER_SIZE);
5887 switched = true;
5890 assemble_integer (XEXP (DECL_RTL (src), 0),
5891 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
5892 assemble_integer (XEXP (DECL_RTL (dst), 0),
5893 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
5897 /* Provide a default for the tm_clone_table section. */
5899 section *
5900 default_clone_table_section (void)
5902 return get_named_section (NULL, ".tm_clone_table", 3);
5905 /* Helper comparison function for qsorting by the DECL_UID stored in
5906 alias_pair->emitted_diags. */
5908 static int
5909 tm_alias_pair_cmp (const void *x, const void *y)
5911 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
5912 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
5913 if (p1->uid < p2->uid)
5914 return -1;
5915 if (p1->uid > p2->uid)
5916 return 1;
5917 return 0;
5920 void
5921 finish_tm_clone_pairs (void)
5923 vec<tm_alias_pair> tm_alias_pairs = vNULL;
5925 if (tm_clone_hash == NULL)
5926 return;
5928 /* We need a determenistic order for the .tm_clone_table, otherwise
5929 we will get bootstrap comparison failures, so dump the hash table
5930 to a vector, sort it, and dump the vector. */
5932 /* Dump the hashtable to a vector. */
5933 tree_map *map;
5934 hash_table<tm_clone_hasher>::iterator iter;
5935 FOR_EACH_HASH_TABLE_ELEMENT (*tm_clone_hash, map, tree_map *, iter)
5937 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
5938 tm_alias_pairs.safe_push (p);
5940 /* Sort it. */
5941 tm_alias_pairs.qsort (tm_alias_pair_cmp);
5943 /* Dump it. */
5944 dump_tm_clone_pairs (tm_alias_pairs);
5946 tm_clone_hash->empty ();
5947 tm_clone_hash = NULL;
5948 tm_alias_pairs.release ();
5952 /* Emit an assembler directive to set symbol for DECL visibility to
5953 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
5955 void
5956 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
5957 int vis ATTRIBUTE_UNUSED)
5959 #ifdef HAVE_GAS_HIDDEN
5960 static const char * const visibility_types[] = {
5961 NULL, "protected", "hidden", "internal"
5964 const char *name, *type;
5965 tree id;
5967 id = DECL_ASSEMBLER_NAME (decl);
5968 ultimate_transparent_alias_target (&id);
5969 name = IDENTIFIER_POINTER (id);
5971 type = visibility_types[vis];
5973 fprintf (asm_out_file, "\t.%s\t", type);
5974 assemble_name (asm_out_file, name);
5975 fprintf (asm_out_file, "\n");
5976 #else
5977 if (!DECL_ARTIFICIAL (decl))
5978 warning (OPT_Wattributes, "visibility attribute not supported "
5979 "in this configuration; ignored");
5980 #endif
5983 /* A helper function to call assemble_visibility when needed for a decl. */
5986 maybe_assemble_visibility (tree decl)
5988 enum symbol_visibility vis = DECL_VISIBILITY (decl);
5990 if (TREE_CODE (decl) == FUNCTION_DECL
5991 && cgraph_node::get (decl)
5992 && cgraph_node::get (decl)->instrumentation_clone
5993 && cgraph_node::get (decl)->instrumented_version)
5994 vis = DECL_VISIBILITY (cgraph_node::get (decl)->instrumented_version->decl);
5996 if (vis != VISIBILITY_DEFAULT)
5998 targetm.asm_out.assemble_visibility (decl, vis);
5999 return 1;
6001 else
6002 return 0;
6005 /* Returns 1 if the target configuration supports defining public symbols
6006 so that one of them will be chosen at link time instead of generating a
6007 multiply-defined symbol error, whether through the use of weak symbols or
6008 a target-specific mechanism for having duplicates discarded. */
6011 supports_one_only (void)
6013 if (SUPPORTS_ONE_ONLY)
6014 return 1;
6015 return TARGET_SUPPORTS_WEAK;
6018 /* Set up DECL as a public symbol that can be defined in multiple
6019 translation units without generating a linker error. */
6021 void
6022 make_decl_one_only (tree decl, tree comdat_group)
6024 struct symtab_node *symbol;
6025 gcc_assert (VAR_OR_FUNCTION_DECL_P (decl));
6027 TREE_PUBLIC (decl) = 1;
6029 if (VAR_P (decl))
6030 symbol = varpool_node::get_create (decl);
6031 else
6032 symbol = cgraph_node::get_create (decl);
6034 if (SUPPORTS_ONE_ONLY)
6036 #ifdef MAKE_DECL_ONE_ONLY
6037 MAKE_DECL_ONE_ONLY (decl);
6038 #endif
6039 symbol->set_comdat_group (comdat_group);
6041 else if (VAR_P (decl)
6042 && (DECL_INITIAL (decl) == 0
6043 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
6044 DECL_COMMON (decl) = 1;
6045 else
6047 gcc_assert (TARGET_SUPPORTS_WEAK);
6048 DECL_WEAK (decl) = 1;
6052 void
6053 init_varasm_once (void)
6055 section_htab = hash_table<section_hasher>::create_ggc (31);
6056 object_block_htab = hash_table<object_block_hasher>::create_ggc (31);
6057 const_desc_htab = hash_table<tree_descriptor_hasher>::create_ggc (1009);
6059 shared_constant_pool = create_constant_pool ();
6061 #ifdef TEXT_SECTION_ASM_OP
6062 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
6063 TEXT_SECTION_ASM_OP);
6064 #endif
6066 #ifdef DATA_SECTION_ASM_OP
6067 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
6068 DATA_SECTION_ASM_OP);
6069 #endif
6071 #ifdef SDATA_SECTION_ASM_OP
6072 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
6073 SDATA_SECTION_ASM_OP);
6074 #endif
6076 #ifdef READONLY_DATA_SECTION_ASM_OP
6077 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
6078 READONLY_DATA_SECTION_ASM_OP);
6079 #endif
6081 #ifdef CTORS_SECTION_ASM_OP
6082 ctors_section = get_unnamed_section (0, output_section_asm_op,
6083 CTORS_SECTION_ASM_OP);
6084 #endif
6086 #ifdef DTORS_SECTION_ASM_OP
6087 dtors_section = get_unnamed_section (0, output_section_asm_op,
6088 DTORS_SECTION_ASM_OP);
6089 #endif
6091 #ifdef BSS_SECTION_ASM_OP
6092 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6093 output_section_asm_op,
6094 BSS_SECTION_ASM_OP);
6095 #endif
6097 #ifdef SBSS_SECTION_ASM_OP
6098 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6099 output_section_asm_op,
6100 SBSS_SECTION_ASM_OP);
6101 #endif
6103 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6104 | SECTION_COMMON, emit_tls_common);
6105 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6106 | SECTION_COMMON, emit_local);
6107 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6108 | SECTION_COMMON, emit_common);
6110 #if defined ASM_OUTPUT_ALIGNED_BSS
6111 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
6112 emit_bss);
6113 #endif
6115 targetm.asm_out.init_sections ();
6117 if (readonly_data_section == NULL)
6118 readonly_data_section = text_section;
6120 #ifdef ASM_OUTPUT_EXTERNAL
6121 pending_assemble_externals_set = new hash_set<tree>;
6122 #endif
6125 enum tls_model
6126 decl_default_tls_model (const_tree decl)
6128 enum tls_model kind;
6129 bool is_local;
6131 is_local = targetm.binds_local_p (decl);
6132 if (!flag_shlib)
6134 if (is_local)
6135 kind = TLS_MODEL_LOCAL_EXEC;
6136 else
6137 kind = TLS_MODEL_INITIAL_EXEC;
6140 /* Local dynamic is inefficient when we're not combining the
6141 parts of the address. */
6142 else if (optimize && is_local)
6143 kind = TLS_MODEL_LOCAL_DYNAMIC;
6144 else
6145 kind = TLS_MODEL_GLOBAL_DYNAMIC;
6146 if (kind < flag_tls_default)
6147 kind = flag_tls_default;
6149 return kind;
6152 /* Select a set of attributes for section NAME based on the properties
6153 of DECL and whether or not RELOC indicates that DECL's initializer
6154 might contain runtime relocations.
6156 We make the section read-only and executable for a function decl,
6157 read-only for a const data decl, and writable for a non-const data decl. */
6159 unsigned int
6160 default_section_type_flags (tree decl, const char *name, int reloc)
6162 unsigned int flags;
6164 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6165 flags = SECTION_CODE;
6166 else if (decl)
6168 enum section_category category
6169 = categorize_decl_for_section (decl, reloc);
6170 if (decl_readonly_section_1 (category))
6171 flags = 0;
6172 else if (category == SECCAT_DATA_REL_RO
6173 || category == SECCAT_DATA_REL_RO_LOCAL)
6174 flags = SECTION_WRITE | SECTION_RELRO;
6175 else
6176 flags = SECTION_WRITE;
6178 else
6180 flags = SECTION_WRITE;
6181 if (strcmp (name, ".data.rel.ro") == 0
6182 || strcmp (name, ".data.rel.ro.local") == 0)
6183 flags |= SECTION_RELRO;
6186 if (decl && DECL_P (decl) && DECL_COMDAT_GROUP (decl))
6187 flags |= SECTION_LINKONCE;
6189 if (strcmp (name, ".vtable_map_vars") == 0)
6190 flags |= SECTION_LINKONCE;
6192 if (decl && VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6193 flags |= SECTION_TLS | SECTION_WRITE;
6195 if (strcmp (name, ".bss") == 0
6196 || strncmp (name, ".bss.", 5) == 0
6197 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6198 || strcmp (name, ".persistent.bss") == 0
6199 || strcmp (name, ".sbss") == 0
6200 || strncmp (name, ".sbss.", 6) == 0
6201 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6202 flags |= SECTION_BSS;
6204 if (strcmp (name, ".tdata") == 0
6205 || strncmp (name, ".tdata.", 7) == 0
6206 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6207 flags |= SECTION_TLS;
6209 if (strcmp (name, ".tbss") == 0
6210 || strncmp (name, ".tbss.", 6) == 0
6211 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6212 flags |= SECTION_TLS | SECTION_BSS;
6214 /* These three sections have special ELF types. They are neither
6215 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
6216 want to print a section type (@progbits or @nobits). If someone
6217 is silly enough to emit code or TLS variables to one of these
6218 sections, then don't handle them specially. */
6219 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6220 && (strcmp (name, ".init_array") == 0
6221 || strcmp (name, ".fini_array") == 0
6222 || strcmp (name, ".preinit_array") == 0))
6223 flags |= SECTION_NOTYPE;
6225 return flags;
6228 /* Return true if the target supports some form of global BSS,
6229 either through bss_noswitch_section, or by selecting a BSS
6230 section in TARGET_ASM_SELECT_SECTION. */
6232 bool
6233 have_global_bss_p (void)
6235 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6238 /* Output assembly to switch to section NAME with attribute FLAGS.
6239 Four variants for common object file formats. */
6241 void
6242 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6243 unsigned int flags ATTRIBUTE_UNUSED,
6244 tree decl ATTRIBUTE_UNUSED)
6246 /* Some object formats don't support named sections at all. The
6247 front-end should already have flagged this as an error. */
6248 gcc_unreachable ();
6251 #ifndef TLS_SECTION_ASM_FLAG
6252 #define TLS_SECTION_ASM_FLAG 'T'
6253 #endif
6255 void
6256 default_elf_asm_named_section (const char *name, unsigned int flags,
6257 tree decl)
6259 char flagchars[11], *f = flagchars;
6260 unsigned int numeric_value = 0;
6262 /* If we have already declared this section, we can use an
6263 abbreviated form to switch back to it -- unless this section is
6264 part of a COMDAT groups, in which case GAS requires the full
6265 declaration every time. */
6266 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6267 && (flags & SECTION_DECLARED))
6269 fprintf (asm_out_file, "\t.section\t%s\n", name);
6270 return;
6273 /* If we have a machine specific flag, then use the numeric value to pass
6274 this on to GAS. */
6275 if (targetm.asm_out.elf_flags_numeric (flags, &numeric_value))
6276 snprintf (f, sizeof (flagchars), "0x%08x", numeric_value);
6277 else
6279 if (!(flags & SECTION_DEBUG))
6280 *f++ = 'a';
6281 #if defined (HAVE_GAS_SECTION_EXCLUDE) && HAVE_GAS_SECTION_EXCLUDE == 1
6282 if (flags & SECTION_EXCLUDE)
6283 *f++ = 'e';
6284 #endif
6285 if (flags & SECTION_WRITE)
6286 *f++ = 'w';
6287 if (flags & SECTION_CODE)
6288 *f++ = 'x';
6289 if (flags & SECTION_SMALL)
6290 *f++ = 's';
6291 if (flags & SECTION_MERGE)
6292 *f++ = 'M';
6293 if (flags & SECTION_STRINGS)
6294 *f++ = 'S';
6295 if (flags & SECTION_TLS)
6296 *f++ = TLS_SECTION_ASM_FLAG;
6297 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6298 *f++ = 'G';
6299 #ifdef MACH_DEP_SECTION_ASM_FLAG
6300 if (flags & SECTION_MACH_DEP)
6301 *f++ = MACH_DEP_SECTION_ASM_FLAG;
6302 #endif
6303 *f = '\0';
6306 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6308 if (!(flags & SECTION_NOTYPE))
6310 const char *type;
6311 const char *format;
6313 if (flags & SECTION_BSS)
6314 type = "nobits";
6315 else
6316 type = "progbits";
6318 format = ",@%s";
6319 /* On platforms that use "@" as the assembly comment character,
6320 use "%" instead. */
6321 if (strcmp (ASM_COMMENT_START, "@") == 0)
6322 format = ",%%%s";
6323 fprintf (asm_out_file, format, type);
6325 if (flags & SECTION_ENTSIZE)
6326 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6327 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6329 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6330 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6331 else
6332 fprintf (asm_out_file, ",%s,comdat",
6333 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6337 putc ('\n', asm_out_file);
6340 void
6341 default_coff_asm_named_section (const char *name, unsigned int flags,
6342 tree decl ATTRIBUTE_UNUSED)
6344 char flagchars[8], *f = flagchars;
6346 if (flags & SECTION_WRITE)
6347 *f++ = 'w';
6348 if (flags & SECTION_CODE)
6349 *f++ = 'x';
6350 *f = '\0';
6352 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6355 void
6356 default_pe_asm_named_section (const char *name, unsigned int flags,
6357 tree decl)
6359 default_coff_asm_named_section (name, flags, decl);
6361 if (flags & SECTION_LINKONCE)
6363 /* Functions may have been compiled at various levels of
6364 optimization so we can't use `same_size' here.
6365 Instead, have the linker pick one. */
6366 fprintf (asm_out_file, "\t.linkonce %s\n",
6367 (flags & SECTION_CODE ? "discard" : "same_size"));
6371 /* The lame default section selector. */
6373 section *
6374 default_select_section (tree decl, int reloc,
6375 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6377 if (DECL_P (decl))
6379 if (decl_readonly_section (decl, reloc))
6380 return readonly_data_section;
6382 else if (TREE_CODE (decl) == CONSTRUCTOR)
6384 if (! ((flag_pic && reloc)
6385 || !TREE_READONLY (decl)
6386 || TREE_SIDE_EFFECTS (decl)
6387 || !TREE_CONSTANT (decl)))
6388 return readonly_data_section;
6390 else if (TREE_CODE (decl) == STRING_CST)
6391 return readonly_data_section;
6392 else if (! (flag_pic && reloc))
6393 return readonly_data_section;
6395 return data_section;
6398 enum section_category
6399 categorize_decl_for_section (const_tree decl, int reloc)
6401 enum section_category ret;
6403 if (TREE_CODE (decl) == FUNCTION_DECL)
6404 return SECCAT_TEXT;
6405 else if (TREE_CODE (decl) == STRING_CST)
6407 if ((flag_sanitize & SANITIZE_ADDRESS)
6408 && asan_protect_global (CONST_CAST_TREE (decl)))
6409 /* or !flag_merge_constants */
6410 return SECCAT_RODATA;
6411 else
6412 return SECCAT_RODATA_MERGE_STR;
6414 else if (VAR_P (decl))
6416 if (bss_initializer_p (decl))
6417 ret = SECCAT_BSS;
6418 else if (! TREE_READONLY (decl)
6419 || TREE_SIDE_EFFECTS (decl)
6420 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
6422 /* Here the reloc_rw_mask is not testing whether the section should
6423 be read-only or not, but whether the dynamic link will have to
6424 do something. If so, we wish to segregate the data in order to
6425 minimize cache misses inside the dynamic linker. */
6426 if (reloc & targetm.asm_out.reloc_rw_mask ())
6427 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6428 else
6429 ret = SECCAT_DATA;
6431 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6432 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6433 else if (reloc || flag_merge_constants < 2
6434 || ((flag_sanitize & SANITIZE_ADDRESS)
6435 && asan_protect_global (CONST_CAST_TREE (decl))))
6436 /* C and C++ don't allow different variables to share the same
6437 location. -fmerge-all-constants allows even that (at the
6438 expense of not conforming). */
6439 ret = SECCAT_RODATA;
6440 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6441 ret = SECCAT_RODATA_MERGE_STR_INIT;
6442 else
6443 ret = SECCAT_RODATA_MERGE_CONST;
6445 else if (TREE_CODE (decl) == CONSTRUCTOR)
6447 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6448 || TREE_SIDE_EFFECTS (decl)
6449 || ! TREE_CONSTANT (decl))
6450 ret = SECCAT_DATA;
6451 else
6452 ret = SECCAT_RODATA;
6454 else
6455 ret = SECCAT_RODATA;
6457 /* There are no read-only thread-local sections. */
6458 if (VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6460 /* Note that this would be *just* SECCAT_BSS, except that there's
6461 no concept of a read-only thread-local-data section. */
6462 if (ret == SECCAT_BSS
6463 || (flag_zero_initialized_in_bss
6464 && initializer_zerop (DECL_INITIAL (decl))))
6465 ret = SECCAT_TBSS;
6466 else
6467 ret = SECCAT_TDATA;
6470 /* If the target uses small data sections, select it. */
6471 else if (targetm.in_small_data_p (decl))
6473 if (ret == SECCAT_BSS)
6474 ret = SECCAT_SBSS;
6475 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6476 ret = SECCAT_SRODATA;
6477 else
6478 ret = SECCAT_SDATA;
6481 return ret;
6484 static bool
6485 decl_readonly_section_1 (enum section_category category)
6487 switch (category)
6489 case SECCAT_RODATA:
6490 case SECCAT_RODATA_MERGE_STR:
6491 case SECCAT_RODATA_MERGE_STR_INIT:
6492 case SECCAT_RODATA_MERGE_CONST:
6493 case SECCAT_SRODATA:
6494 return true;
6495 default:
6496 return false;
6500 bool
6501 decl_readonly_section (const_tree decl, int reloc)
6503 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6506 /* Select a section based on the above categorization. */
6508 section *
6509 default_elf_select_section (tree decl, int reloc,
6510 unsigned HOST_WIDE_INT align)
6512 const char *sname;
6513 switch (categorize_decl_for_section (decl, reloc))
6515 case SECCAT_TEXT:
6516 /* We're not supposed to be called on FUNCTION_DECLs. */
6517 gcc_unreachable ();
6518 case SECCAT_RODATA:
6519 return readonly_data_section;
6520 case SECCAT_RODATA_MERGE_STR:
6521 return mergeable_string_section (decl, align, 0);
6522 case SECCAT_RODATA_MERGE_STR_INIT:
6523 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6524 case SECCAT_RODATA_MERGE_CONST:
6525 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6526 case SECCAT_SRODATA:
6527 sname = ".sdata2";
6528 break;
6529 case SECCAT_DATA:
6530 return data_section;
6531 case SECCAT_DATA_REL:
6532 sname = ".data.rel";
6533 break;
6534 case SECCAT_DATA_REL_LOCAL:
6535 sname = ".data.rel.local";
6536 break;
6537 case SECCAT_DATA_REL_RO:
6538 sname = ".data.rel.ro";
6539 break;
6540 case SECCAT_DATA_REL_RO_LOCAL:
6541 sname = ".data.rel.ro.local";
6542 break;
6543 case SECCAT_SDATA:
6544 sname = ".sdata";
6545 break;
6546 case SECCAT_TDATA:
6547 sname = ".tdata";
6548 break;
6549 case SECCAT_BSS:
6550 if (bss_section)
6551 return bss_section;
6552 sname = ".bss";
6553 break;
6554 case SECCAT_SBSS:
6555 sname = ".sbss";
6556 break;
6557 case SECCAT_TBSS:
6558 sname = ".tbss";
6559 break;
6560 default:
6561 gcc_unreachable ();
6564 return get_named_section (decl, sname, reloc);
6567 /* Construct a unique section name based on the decl name and the
6568 categorization performed above. */
6570 void
6571 default_unique_section (tree decl, int reloc)
6573 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6574 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6575 const char *prefix, *name, *linkonce;
6576 char *string;
6577 tree id;
6579 switch (categorize_decl_for_section (decl, reloc))
6581 case SECCAT_TEXT:
6582 prefix = one_only ? ".t" : ".text";
6583 break;
6584 case SECCAT_RODATA:
6585 case SECCAT_RODATA_MERGE_STR:
6586 case SECCAT_RODATA_MERGE_STR_INIT:
6587 case SECCAT_RODATA_MERGE_CONST:
6588 prefix = one_only ? ".r" : ".rodata";
6589 break;
6590 case SECCAT_SRODATA:
6591 prefix = one_only ? ".s2" : ".sdata2";
6592 break;
6593 case SECCAT_DATA:
6594 prefix = one_only ? ".d" : ".data";
6595 break;
6596 case SECCAT_DATA_REL:
6597 prefix = one_only ? ".d.rel" : ".data.rel";
6598 break;
6599 case SECCAT_DATA_REL_LOCAL:
6600 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6601 break;
6602 case SECCAT_DATA_REL_RO:
6603 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6604 break;
6605 case SECCAT_DATA_REL_RO_LOCAL:
6606 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6607 break;
6608 case SECCAT_SDATA:
6609 prefix = one_only ? ".s" : ".sdata";
6610 break;
6611 case SECCAT_BSS:
6612 prefix = one_only ? ".b" : ".bss";
6613 break;
6614 case SECCAT_SBSS:
6615 prefix = one_only ? ".sb" : ".sbss";
6616 break;
6617 case SECCAT_TDATA:
6618 prefix = one_only ? ".td" : ".tdata";
6619 break;
6620 case SECCAT_TBSS:
6621 prefix = one_only ? ".tb" : ".tbss";
6622 break;
6623 default:
6624 gcc_unreachable ();
6627 id = DECL_ASSEMBLER_NAME (decl);
6628 ultimate_transparent_alias_target (&id);
6629 name = IDENTIFIER_POINTER (id);
6630 name = targetm.strip_name_encoding (name);
6632 /* If we're using one_only, then there needs to be a .gnu.linkonce
6633 prefix to the section name. */
6634 linkonce = one_only ? ".gnu.linkonce" : "";
6636 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6638 set_decl_section_name (decl, string);
6641 /* Subroutine of compute_reloc_for_rtx for leaf rtxes. */
6643 static int
6644 compute_reloc_for_rtx_1 (const_rtx x)
6646 switch (GET_CODE (x))
6648 case SYMBOL_REF:
6649 return SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6650 case LABEL_REF:
6651 return 1;
6652 default:
6653 return 0;
6657 /* Like compute_reloc_for_constant, except for an RTX. The return value
6658 is a mask for which bit 1 indicates a global relocation, and bit 0
6659 indicates a local relocation. */
6661 static int
6662 compute_reloc_for_rtx (const_rtx x)
6664 switch (GET_CODE (x))
6666 case SYMBOL_REF:
6667 case LABEL_REF:
6668 return compute_reloc_for_rtx_1 (x);
6670 case CONST:
6672 int reloc = 0;
6673 subrtx_iterator::array_type array;
6674 FOR_EACH_SUBRTX (iter, array, x, ALL)
6675 reloc |= compute_reloc_for_rtx_1 (*iter);
6676 return reloc;
6679 default:
6680 return 0;
6684 section *
6685 default_select_rtx_section (machine_mode mode ATTRIBUTE_UNUSED,
6686 rtx x,
6687 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6689 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6690 return data_section;
6691 else
6692 return readonly_data_section;
6695 section *
6696 default_elf_select_rtx_section (machine_mode mode, rtx x,
6697 unsigned HOST_WIDE_INT align)
6699 int reloc = compute_reloc_for_rtx (x);
6701 /* ??? Handle small data here somehow. */
6703 if (reloc & targetm.asm_out.reloc_rw_mask ())
6705 if (reloc == 1)
6706 return get_named_section (NULL, ".data.rel.ro.local", 1);
6707 else
6708 return get_named_section (NULL, ".data.rel.ro", 3);
6711 return mergeable_constant_section (mode, align, 0);
6714 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6716 void
6717 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6719 rtx symbol;
6720 int flags;
6722 /* Careful not to prod global register variables. */
6723 if (!MEM_P (rtl))
6724 return;
6725 symbol = XEXP (rtl, 0);
6726 if (GET_CODE (symbol) != SYMBOL_REF)
6727 return;
6729 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6730 if (TREE_CODE (decl) == FUNCTION_DECL)
6731 flags |= SYMBOL_FLAG_FUNCTION;
6732 if (targetm.binds_local_p (decl))
6733 flags |= SYMBOL_FLAG_LOCAL;
6734 if (VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6735 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6736 else if (targetm.in_small_data_p (decl))
6737 flags |= SYMBOL_FLAG_SMALL;
6738 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6739 being PUBLIC, the thing *must* be defined in this translation unit.
6740 Prevent this buglet from being propagated into rtl code as well. */
6741 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6742 flags |= SYMBOL_FLAG_EXTERNAL;
6744 SYMBOL_REF_FLAGS (symbol) = flags;
6747 /* By default, we do nothing for encode_section_info, so we need not
6748 do anything but discard the '*' marker. */
6750 const char *
6751 default_strip_name_encoding (const char *str)
6753 return str + (*str == '*');
6756 #ifdef ASM_OUTPUT_DEF
6757 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6758 anchor relative to ".", the current section position. */
6760 void
6761 default_asm_output_anchor (rtx symbol)
6763 char buffer[100];
6765 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6766 SYMBOL_REF_BLOCK_OFFSET (symbol));
6767 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6769 #endif
6771 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6773 bool
6774 default_use_anchors_for_symbol_p (const_rtx symbol)
6776 section *sect;
6777 tree decl;
6779 /* Don't use anchors for mergeable sections. The linker might move
6780 the objects around. */
6781 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6782 if (sect->common.flags & SECTION_MERGE)
6783 return false;
6785 /* Don't use anchors for small data sections. The small data register
6786 acts as an anchor for such sections. */
6787 if (sect->common.flags & SECTION_SMALL)
6788 return false;
6790 decl = SYMBOL_REF_DECL (symbol);
6791 if (decl && DECL_P (decl))
6793 /* Don't use section anchors for decls that might be defined or
6794 usurped by other modules. */
6795 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6796 return false;
6798 /* Don't use section anchors for decls that will be placed in a
6799 small data section. */
6800 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6801 one above. The problem is that we only use SECTION_SMALL for
6802 sections that should be marked as small in the section directive. */
6803 if (targetm.in_small_data_p (decl))
6804 return false;
6806 /* Don't use section anchors for decls that won't fit inside a single
6807 anchor range to reduce the amount of instructions require to refer
6808 to the entire declaration. */
6809 if (decl && DECL_SIZE (decl)
6810 && tree_to_shwi (DECL_SIZE (decl))
6811 >= (targetm.max_anchor_offset * BITS_PER_UNIT))
6812 return false;
6815 return true;
6818 /* Return true when RESOLUTION indicate that symbol will be bound to the
6819 definition provided by current .o file. */
6821 static bool
6822 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
6824 return (resolution == LDPR_PREVAILING_DEF
6825 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6826 || resolution == LDPR_PREVAILING_DEF_IRONLY);
6829 /* Return true when RESOLUTION indicate that symbol will be bound locally
6830 within current executable or DSO. */
6832 static bool
6833 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
6835 return (resolution == LDPR_PREVAILING_DEF
6836 || resolution == LDPR_PREVAILING_DEF_IRONLY
6837 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6838 || resolution == LDPR_PREEMPTED_REG
6839 || resolution == LDPR_PREEMPTED_IR
6840 || resolution == LDPR_RESOLVED_IR
6841 || resolution == LDPR_RESOLVED_EXEC);
6844 /* COMMON_LOCAL_P is true means that the linker can guarantee that an
6845 uninitialized common symbol in the executable will still be defined
6846 (through COPY relocation) in the executable. */
6848 bool
6849 default_binds_local_p_3 (const_tree exp, bool shlib, bool weak_dominate,
6850 bool extern_protected_data, bool common_local_p)
6852 /* A non-decl is an entry in the constant pool. */
6853 if (!DECL_P (exp))
6854 return true;
6856 /* Weakrefs may not bind locally, even though the weakref itself is always
6857 static and therefore local. Similarly, the resolver for ifunc functions
6858 might resolve to a non-local function.
6859 FIXME: We can resolve the weakref case more curefuly by looking at the
6860 weakref alias. */
6861 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
6862 || (TREE_CODE (exp) == FUNCTION_DECL
6863 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
6864 return false;
6866 /* Static variables are always local. */
6867 if (! TREE_PUBLIC (exp))
6868 return true;
6870 /* With resolution file in hand, take look into resolutions.
6871 We can't just return true for resolved_locally symbols,
6872 because dynamic linking might overwrite symbols
6873 in shared libraries. */
6874 bool resolved_locally = false;
6876 bool uninited_common = (DECL_COMMON (exp)
6877 && (DECL_INITIAL (exp) == NULL
6878 || (!in_lto_p
6879 && DECL_INITIAL (exp) == error_mark_node)));
6881 /* A non-external variable is defined locally only if it isn't
6882 uninitialized COMMON variable or common_local_p is true. */
6883 bool defined_locally = (!DECL_EXTERNAL (exp)
6884 && (!uninited_common || common_local_p));
6885 if (symtab_node *node = symtab_node::get (exp))
6887 if (node->in_other_partition)
6888 defined_locally = true;
6889 if (node->can_be_discarded_p ())
6891 else if (resolution_to_local_definition_p (node->resolution))
6892 defined_locally = resolved_locally = true;
6893 else if (resolution_local_p (node->resolution))
6894 resolved_locally = true;
6896 if (defined_locally && weak_dominate && !shlib)
6897 resolved_locally = true;
6899 /* Undefined weak symbols are never defined locally. */
6900 if (DECL_WEAK (exp) && !defined_locally)
6901 return false;
6903 /* A symbol is local if the user has said explicitly that it will be,
6904 or if we have a definition for the symbol. We cannot infer visibility
6905 for undefined symbols. */
6906 if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT
6907 && (TREE_CODE (exp) == FUNCTION_DECL
6908 || !extern_protected_data
6909 || DECL_VISIBILITY (exp) != VISIBILITY_PROTECTED)
6910 && (DECL_VISIBILITY_SPECIFIED (exp) || defined_locally))
6911 return true;
6913 /* If PIC, then assume that any global name can be overridden by
6914 symbols resolved from other modules. */
6915 if (shlib)
6916 return false;
6918 /* Variables defined outside this object might not be local. */
6919 if (DECL_EXTERNAL (exp) && !resolved_locally)
6920 return false;
6922 /* Non-dominant weak symbols are not defined locally. */
6923 if (DECL_WEAK (exp) && !resolved_locally)
6924 return false;
6926 /* Uninitialized COMMON variable may be unified with symbols
6927 resolved from other modules. */
6928 if (uninited_common && !resolved_locally)
6929 return false;
6931 /* Otherwise we're left with initialized (or non-common) global data
6932 which is of necessity defined locally. */
6933 return true;
6936 /* Assume ELF-ish defaults, since that's pretty much the most liberal
6937 wrt cross-module name binding. */
6939 bool
6940 default_binds_local_p (const_tree exp)
6942 return default_binds_local_p_3 (exp, flag_shlib != 0, true, false, false);
6945 /* Similar to default_binds_local_p, but common symbol may be local and
6946 extern protected data is non-local. */
6948 bool
6949 default_binds_local_p_2 (const_tree exp)
6951 return default_binds_local_p_3 (exp, flag_shlib != 0, true, true,
6952 !flag_pic);
6955 bool
6956 default_binds_local_p_1 (const_tree exp, int shlib)
6958 return default_binds_local_p_3 (exp, shlib != 0, false, false, false);
6961 /* Return true when references to DECL must bind to current definition in
6962 final executable.
6964 The condition is usually equivalent to whether the function binds to the
6965 current module (shared library or executable), that is to binds_local_p.
6966 We use this fact to avoid need for another target hook and implement
6967 the logic using binds_local_p and just special cases where
6968 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
6969 the weak definitions (that can be overwritten at linktime by other
6970 definition from different object file) and when resolution info is available
6971 we simply use the knowledge passed to us by linker plugin. */
6972 bool
6973 decl_binds_to_current_def_p (const_tree decl)
6975 gcc_assert (DECL_P (decl));
6976 if (!targetm.binds_local_p (decl))
6977 return false;
6978 if (!TREE_PUBLIC (decl))
6979 return true;
6981 /* When resolution is available, just use it. */
6982 if (symtab_node *node = symtab_node::get (decl))
6984 if (node->resolution != LDPR_UNKNOWN
6985 && !node->can_be_discarded_p ())
6986 return resolution_to_local_definition_p (node->resolution);
6989 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
6990 binds locally but still can be overwritten), DECL_COMMON (can be merged
6991 with a non-common definition somewhere in the same module) or
6992 DECL_EXTERNAL.
6993 This rely on fact that binds_local_p behave as decl_replaceable_p
6994 for all other declaration types. */
6995 if (DECL_WEAK (decl))
6996 return false;
6997 if (DECL_COMMON (decl)
6998 && (DECL_INITIAL (decl) == NULL
6999 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
7000 return false;
7001 if (DECL_EXTERNAL (decl))
7002 return false;
7003 return true;
7006 /* A replaceable function or variable is one which may be replaced
7007 at link-time with an entirely different definition, provided that the
7008 replacement has the same type. For example, functions declared
7009 with __attribute__((weak)) on most systems are replaceable.
7011 COMDAT functions are not replaceable, since all definitions of the
7012 function must be equivalent. It is important that COMDAT functions
7013 not be treated as replaceable so that use of C++ template
7014 instantiations is not penalized. */
7016 bool
7017 decl_replaceable_p (tree decl)
7019 gcc_assert (DECL_P (decl));
7020 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
7021 return false;
7022 if (!flag_semantic_interposition
7023 && !DECL_WEAK (decl))
7024 return false;
7025 return !decl_binds_to_current_def_p (decl);
7028 /* Default function to output code that will globalize a label. A
7029 target must define GLOBAL_ASM_OP or provide its own function to
7030 globalize a label. */
7031 #ifdef GLOBAL_ASM_OP
7032 void
7033 default_globalize_label (FILE * stream, const char *name)
7035 fputs (GLOBAL_ASM_OP, stream);
7036 assemble_name (stream, name);
7037 putc ('\n', stream);
7039 #endif /* GLOBAL_ASM_OP */
7041 /* Default function to output code that will globalize a declaration. */
7042 void
7043 default_globalize_decl_name (FILE * stream, tree decl)
7045 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
7046 targetm.asm_out.globalize_label (stream, name);
7049 /* Default function to output a label for unwind information. The
7050 default is to do nothing. A target that needs nonlocal labels for
7051 unwind information must provide its own function to do this. */
7052 void
7053 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
7054 tree decl ATTRIBUTE_UNUSED,
7055 int for_eh ATTRIBUTE_UNUSED,
7056 int empty ATTRIBUTE_UNUSED)
7060 /* Default function to output a label to divide up the exception table.
7061 The default is to do nothing. A target that needs/wants to divide
7062 up the table must provide it's own function to do this. */
7063 void
7064 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
7068 /* This is how to output an internal numbered label where PREFIX is
7069 the class of label and LABELNO is the number within the class. */
7071 void
7072 default_generate_internal_label (char *buf, const char *prefix,
7073 unsigned long labelno)
7075 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
7078 /* This is how to output an internal numbered label where PREFIX is
7079 the class of label and LABELNO is the number within the class. */
7081 void
7082 default_internal_label (FILE *stream, const char *prefix,
7083 unsigned long labelno)
7085 char *const buf = (char *) alloca (40 + strlen (prefix));
7086 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
7087 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
7091 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
7093 void
7094 default_asm_declare_constant_name (FILE *file, const char *name,
7095 const_tree exp ATTRIBUTE_UNUSED,
7096 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
7098 assemble_label (file, name);
7101 /* This is the default behavior at the beginning of a file. It's
7102 controlled by two other target-hook toggles. */
7103 void
7104 default_file_start (void)
7106 if (targetm.asm_file_start_app_off
7107 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
7108 fputs (ASM_APP_OFF, asm_out_file);
7110 if (targetm.asm_file_start_file_directive)
7112 /* LTO produced units have no meaningful main_input_filename. */
7113 if (in_lto_p)
7114 output_file_directive (asm_out_file, "<artificial>");
7115 else
7116 output_file_directive (asm_out_file, main_input_filename);
7120 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
7121 which emits a special section directive used to indicate whether or
7122 not this object file needs an executable stack. This is primarily
7123 a GNU extension to ELF but could be used on other targets. */
7125 int trampolines_created;
7127 void
7128 file_end_indicate_exec_stack (void)
7130 unsigned int flags = SECTION_DEBUG;
7131 if (trampolines_created)
7132 flags |= SECTION_CODE;
7134 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
7137 /* Emit a special section directive to indicate that this object file
7138 was compiled with -fsplit-stack. This is used to let the linker
7139 detect calls between split-stack code and non-split-stack code, so
7140 that it can modify the split-stack code to allocate a sufficiently
7141 large stack. We emit another special section if there are any
7142 functions in this file which have the no_split_stack attribute, to
7143 prevent the linker from warning about being unable to convert the
7144 functions if they call non-split-stack code. */
7146 void
7147 file_end_indicate_split_stack (void)
7149 if (flag_split_stack)
7151 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
7152 NULL));
7153 if (saw_no_split_stack)
7154 switch_to_section (get_section (".note.GNU-no-split-stack",
7155 SECTION_DEBUG, NULL));
7159 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
7160 a get_unnamed_section callback. */
7162 void
7163 output_section_asm_op (const void *directive)
7165 fprintf (asm_out_file, "%s\n", (const char *) directive);
7168 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
7169 the current section is NEW_SECTION. */
7171 void
7172 switch_to_section (section *new_section)
7174 if (in_section == new_section)
7175 return;
7177 if (new_section->common.flags & SECTION_FORGET)
7178 in_section = NULL;
7179 else
7180 in_section = new_section;
7182 switch (SECTION_STYLE (new_section))
7184 case SECTION_NAMED:
7185 targetm.asm_out.named_section (new_section->named.name,
7186 new_section->named.common.flags,
7187 new_section->named.decl);
7188 break;
7190 case SECTION_UNNAMED:
7191 new_section->unnamed.callback (new_section->unnamed.data);
7192 break;
7194 case SECTION_NOSWITCH:
7195 gcc_unreachable ();
7196 break;
7199 new_section->common.flags |= SECTION_DECLARED;
7202 /* If block symbol SYMBOL has not yet been assigned an offset, place
7203 it at the end of its block. */
7205 void
7206 place_block_symbol (rtx symbol)
7208 unsigned HOST_WIDE_INT size, mask, offset;
7209 struct constant_descriptor_rtx *desc;
7210 unsigned int alignment;
7211 struct object_block *block;
7212 tree decl;
7214 gcc_assert (SYMBOL_REF_BLOCK (symbol));
7215 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7216 return;
7218 /* Work out the symbol's size and alignment. */
7219 if (CONSTANT_POOL_ADDRESS_P (symbol))
7221 desc = SYMBOL_REF_CONSTANT (symbol);
7222 alignment = desc->align;
7223 size = GET_MODE_SIZE (desc->mode);
7225 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7227 decl = SYMBOL_REF_DECL (symbol);
7228 gcc_checking_assert (DECL_IN_CONSTANT_POOL (decl));
7229 alignment = DECL_ALIGN (decl);
7230 size = get_constant_size (DECL_INITIAL (decl));
7231 if ((flag_sanitize & SANITIZE_ADDRESS)
7232 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7233 && asan_protect_global (DECL_INITIAL (decl)))
7235 size += asan_red_zone_size (size);
7236 alignment = MAX (alignment,
7237 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7240 else
7242 struct symtab_node *snode;
7243 decl = SYMBOL_REF_DECL (symbol);
7245 snode = symtab_node::get (decl);
7246 if (snode->alias)
7248 rtx target = DECL_RTL (snode->ultimate_alias_target ()->decl);
7250 gcc_assert (MEM_P (target)
7251 && GET_CODE (XEXP (target, 0)) == SYMBOL_REF
7252 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (target, 0)));
7253 target = XEXP (target, 0);
7254 place_block_symbol (target);
7255 SYMBOL_REF_BLOCK_OFFSET (symbol) = SYMBOL_REF_BLOCK_OFFSET (target);
7256 return;
7258 alignment = get_variable_align (decl);
7259 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7260 if ((flag_sanitize & SANITIZE_ADDRESS)
7261 && asan_protect_global (decl))
7263 size += asan_red_zone_size (size);
7264 alignment = MAX (alignment,
7265 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7269 /* Calculate the object's offset from the start of the block. */
7270 block = SYMBOL_REF_BLOCK (symbol);
7271 mask = alignment / BITS_PER_UNIT - 1;
7272 offset = (block->size + mask) & ~mask;
7273 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7275 /* Record the block's new alignment and size. */
7276 block->alignment = MAX (block->alignment, alignment);
7277 block->size = offset + size;
7279 vec_safe_push (block->objects, symbol);
7282 /* Return the anchor that should be used to address byte offset OFFSET
7283 from the first object in BLOCK. MODEL is the TLS model used
7284 to access it. */
7287 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7288 enum tls_model model)
7290 char label[100];
7291 unsigned int begin, middle, end;
7292 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7293 rtx anchor;
7295 /* Work out the anchor's offset. Use an offset of 0 for the first
7296 anchor so that we don't pessimize the case where we take the address
7297 of a variable at the beginning of the block. This is particularly
7298 useful when a block has only one variable assigned to it.
7300 We try to place anchors RANGE bytes apart, so there can then be
7301 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7302 a ptr_mode offset. With some target settings, the lowest such
7303 anchor might be out of range for the lowest ptr_mode offset;
7304 likewise the highest anchor for the highest offset. Use anchors
7305 at the extreme ends of the ptr_mode range in such cases.
7307 All arithmetic uses unsigned integers in order to avoid
7308 signed overflow. */
7309 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7310 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7311 range = max_offset - min_offset + 1;
7312 if (range == 0)
7313 offset = 0;
7314 else
7316 bias = HOST_WIDE_INT_1U << (GET_MODE_BITSIZE (ptr_mode) - 1);
7317 if (offset < 0)
7319 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7320 delta -= delta % range;
7321 if (delta > bias)
7322 delta = bias;
7323 offset = (HOST_WIDE_INT) (-delta);
7325 else
7327 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7328 delta -= delta % range;
7329 if (delta > bias - 1)
7330 delta = bias - 1;
7331 offset = (HOST_WIDE_INT) delta;
7335 /* Do a binary search to see if there's already an anchor we can use.
7336 Set BEGIN to the new anchor's index if not. */
7337 begin = 0;
7338 end = vec_safe_length (block->anchors);
7339 while (begin != end)
7341 middle = (end + begin) / 2;
7342 anchor = (*block->anchors)[middle];
7343 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7344 end = middle;
7345 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7346 begin = middle + 1;
7347 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7348 end = middle;
7349 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7350 begin = middle + 1;
7351 else
7352 return anchor;
7355 /* Create a new anchor with a unique label. */
7356 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7357 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7358 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7359 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7361 /* Insert it at index BEGIN. */
7362 vec_safe_insert (block->anchors, begin, anchor);
7363 return anchor;
7366 /* Output the objects in BLOCK. */
7368 static void
7369 output_object_block (struct object_block *block)
7371 struct constant_descriptor_rtx *desc;
7372 unsigned int i;
7373 HOST_WIDE_INT offset;
7374 tree decl;
7375 rtx symbol;
7377 if (!block->objects)
7378 return;
7380 /* Switch to the section and make sure that the first byte is
7381 suitably aligned. */
7382 /* Special case VTV comdat sections similar to assemble_variable. */
7383 if (SECTION_STYLE (block->sect) == SECTION_NAMED
7384 && block->sect->named.name
7385 && (strcmp (block->sect->named.name, ".vtable_map_vars") == 0))
7386 handle_vtv_comdat_section (block->sect, block->sect->named.decl);
7387 else
7388 switch_to_section (block->sect);
7390 assemble_align (block->alignment);
7392 /* Define the values of all anchors relative to the current section
7393 position. */
7394 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7395 targetm.asm_out.output_anchor (symbol);
7397 /* Output the objects themselves. */
7398 offset = 0;
7399 FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7401 /* Move to the object's offset, padding with zeros if necessary. */
7402 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7403 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7404 if (CONSTANT_POOL_ADDRESS_P (symbol))
7406 desc = SYMBOL_REF_CONSTANT (symbol);
7407 /* Pass 1 for align as we have already laid out everything in the block.
7408 So aligning shouldn't be necessary. */
7409 output_constant_pool_1 (desc, 1);
7410 offset += GET_MODE_SIZE (desc->mode);
7412 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7414 HOST_WIDE_INT size;
7415 decl = SYMBOL_REF_DECL (symbol);
7416 assemble_constant_contents
7417 (DECL_INITIAL (decl), XSTR (symbol, 0), DECL_ALIGN (decl));
7419 size = get_constant_size (DECL_INITIAL (decl));
7420 offset += size;
7421 if ((flag_sanitize & SANITIZE_ADDRESS)
7422 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7423 && asan_protect_global (DECL_INITIAL (decl)))
7425 size = asan_red_zone_size (size);
7426 assemble_zeros (size);
7427 offset += size;
7430 else
7432 HOST_WIDE_INT size;
7433 decl = SYMBOL_REF_DECL (symbol);
7434 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7435 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7436 offset += size;
7437 if ((flag_sanitize & SANITIZE_ADDRESS)
7438 && asan_protect_global (decl))
7440 size = asan_red_zone_size (size);
7441 assemble_zeros (size);
7442 offset += size;
7448 /* A callback for qsort to compare object_blocks. */
7450 static int
7451 output_object_block_compare (const void *x, const void *y)
7453 object_block *p1 = *(object_block * const*)x;
7454 object_block *p2 = *(object_block * const*)y;
7456 if (p1->sect->common.flags & SECTION_NAMED
7457 && !(p2->sect->common.flags & SECTION_NAMED))
7458 return 1;
7460 if (!(p1->sect->common.flags & SECTION_NAMED)
7461 && p2->sect->common.flags & SECTION_NAMED)
7462 return -1;
7464 if (p1->sect->common.flags & SECTION_NAMED
7465 && p2->sect->common.flags & SECTION_NAMED)
7466 return strcmp (p1->sect->named.name, p2->sect->named.name);
7468 unsigned f1 = p1->sect->common.flags;
7469 unsigned f2 = p2->sect->common.flags;
7470 if (f1 == f2)
7471 return 0;
7472 return f1 < f2 ? -1 : 1;
7475 /* Output the definitions of all object_blocks. */
7477 void
7478 output_object_blocks (void)
7480 vec<object_block *, va_heap> v;
7481 v.create (object_block_htab->elements ());
7482 object_block *obj;
7483 hash_table<object_block_hasher>::iterator hi;
7485 FOR_EACH_HASH_TABLE_ELEMENT (*object_block_htab, obj, object_block *, hi)
7486 v.quick_push (obj);
7488 /* Sort them in order to output them in a deterministic manner,
7489 otherwise we may get .rodata sections in different orders with
7490 and without -g. */
7491 v.qsort (output_object_block_compare);
7492 unsigned i;
7493 FOR_EACH_VEC_ELT (v, i, obj)
7494 output_object_block (obj);
7496 v.release ();
7499 /* This function provides a possible implementation of the
7500 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7501 by -frecord-gcc-switches it creates a new mergeable, string section in the
7502 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7503 contains the switches in ASCII format.
7505 FIXME: This code does not correctly handle double quote characters
7506 that appear inside strings, (it strips them rather than preserving them).
7507 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7508 characters - instead it treats them as sub-string separators. Since
7509 we want to emit NUL strings terminators into the object file we have to use
7510 ASM_OUTPUT_SKIP. */
7513 elf_record_gcc_switches (print_switch_type type, const char * name)
7515 switch (type)
7517 case SWITCH_TYPE_PASSED:
7518 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7519 ASM_OUTPUT_SKIP (asm_out_file, HOST_WIDE_INT_1U);
7520 break;
7522 case SWITCH_TYPE_DESCRIPTIVE:
7523 if (name == NULL)
7525 /* Distinguish between invocations where name is NULL. */
7526 static bool started = false;
7528 if (!started)
7530 section * sec;
7532 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7533 SECTION_DEBUG
7534 | SECTION_MERGE
7535 | SECTION_STRINGS
7536 | (SECTION_ENTSIZE & 1),
7537 NULL);
7538 switch_to_section (sec);
7539 started = true;
7543 default:
7544 break;
7547 /* The return value is currently ignored by the caller, but must be 0.
7548 For -fverbose-asm the return value would be the number of characters
7549 emitted into the assembler file. */
7550 return 0;
7553 /* Emit text to declare externally defined symbols. It is needed to
7554 properly support non-default visibility. */
7555 void
7556 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7557 tree decl,
7558 const char *name ATTRIBUTE_UNUSED)
7560 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7561 set in order to avoid putting out names that are never really
7562 used. Always output visibility specified in the source. */
7563 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7564 && (DECL_VISIBILITY_SPECIFIED (decl)
7565 || targetm.binds_local_p (decl)))
7566 maybe_assemble_visibility (decl);
7569 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7571 void
7572 default_asm_output_source_filename (FILE *file, const char *name)
7574 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7575 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7576 #else
7577 fprintf (file, "\t.file\t");
7578 output_quoted_string (file, name);
7579 putc ('\n', file);
7580 #endif
7583 /* Output a file name in the form wanted by System V. */
7585 void
7586 output_file_directive (FILE *asm_file, const char *input_name)
7588 int len;
7589 const char *na;
7591 if (input_name == NULL)
7592 input_name = "<stdin>";
7593 else
7594 input_name = remap_debug_filename (input_name);
7596 len = strlen (input_name);
7597 na = input_name + len;
7599 /* NA gets INPUT_NAME sans directory names. */
7600 while (na > input_name)
7602 if (IS_DIR_SEPARATOR (na[-1]))
7603 break;
7604 na--;
7607 targetm.asm_out.output_source_filename (asm_file, na);
7610 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7611 EXP. */
7613 make_debug_expr_from_rtl (const_rtx exp)
7615 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7616 machine_mode mode = GET_MODE (exp);
7617 rtx dval;
7619 DECL_ARTIFICIAL (ddecl) = 1;
7620 if (REG_P (exp) && REG_EXPR (exp))
7621 type = TREE_TYPE (REG_EXPR (exp));
7622 else if (MEM_P (exp) && MEM_EXPR (exp))
7623 type = TREE_TYPE (MEM_EXPR (exp));
7624 else
7625 type = NULL_TREE;
7626 if (type && TYPE_MODE (type) == mode)
7627 TREE_TYPE (ddecl) = type;
7628 else
7629 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7630 DECL_MODE (ddecl) = mode;
7631 dval = gen_rtx_DEBUG_EXPR (mode);
7632 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7633 SET_DECL_RTL (ddecl, dval);
7634 return dval;
7637 #ifdef ELF_ASCII_ESCAPES
7638 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7640 void
7641 default_elf_asm_output_limited_string (FILE *f, const char *s)
7643 int escape;
7644 unsigned char c;
7646 fputs (STRING_ASM_OP, f);
7647 putc ('"', f);
7648 while (*s != '\0')
7650 c = *s;
7651 escape = ELF_ASCII_ESCAPES[c];
7652 switch (escape)
7654 case 0:
7655 putc (c, f);
7656 break;
7657 case 1:
7658 putc ('\\', f);
7659 putc ('0'+((c>>6)&7), f);
7660 putc ('0'+((c>>3)&7), f);
7661 putc ('0'+(c&7), f);
7662 break;
7663 default:
7664 putc ('\\', f);
7665 putc (escape, f);
7666 break;
7668 s++;
7670 putc ('\"', f);
7671 putc ('\n', f);
7674 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7676 void
7677 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7679 const char *limit = s + len;
7680 const char *last_null = NULL;
7681 unsigned bytes_in_chunk = 0;
7682 unsigned char c;
7683 int escape;
7685 for (; s < limit; s++)
7687 const char *p;
7689 if (bytes_in_chunk >= 60)
7691 putc ('\"', f);
7692 putc ('\n', f);
7693 bytes_in_chunk = 0;
7696 if (s > last_null)
7698 for (p = s; p < limit && *p != '\0'; p++)
7699 continue;
7700 last_null = p;
7702 else
7703 p = last_null;
7705 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7707 if (bytes_in_chunk > 0)
7709 putc ('\"', f);
7710 putc ('\n', f);
7711 bytes_in_chunk = 0;
7714 default_elf_asm_output_limited_string (f, s);
7715 s = p;
7717 else
7719 if (bytes_in_chunk == 0)
7720 fputs (ASCII_DATA_ASM_OP "\"", f);
7722 c = *s;
7723 escape = ELF_ASCII_ESCAPES[c];
7724 switch (escape)
7726 case 0:
7727 putc (c, f);
7728 bytes_in_chunk++;
7729 break;
7730 case 1:
7731 putc ('\\', f);
7732 putc ('0'+((c>>6)&7), f);
7733 putc ('0'+((c>>3)&7), f);
7734 putc ('0'+(c&7), f);
7735 bytes_in_chunk += 4;
7736 break;
7737 default:
7738 putc ('\\', f);
7739 putc (escape, f);
7740 bytes_in_chunk += 2;
7741 break;
7747 if (bytes_in_chunk > 0)
7749 putc ('\"', f);
7750 putc ('\n', f);
7753 #endif
7755 static GTY(()) section *elf_init_array_section;
7756 static GTY(()) section *elf_fini_array_section;
7758 static section *
7759 get_elf_initfini_array_priority_section (int priority,
7760 bool constructor_p)
7762 section *sec;
7763 if (priority != DEFAULT_INIT_PRIORITY)
7765 char buf[18];
7766 sprintf (buf, "%s.%.5u",
7767 constructor_p ? ".init_array" : ".fini_array",
7768 priority);
7769 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7771 else
7773 if (constructor_p)
7775 if (elf_init_array_section == NULL)
7776 elf_init_array_section
7777 = get_section (".init_array",
7778 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7779 sec = elf_init_array_section;
7781 else
7783 if (elf_fini_array_section == NULL)
7784 elf_fini_array_section
7785 = get_section (".fini_array",
7786 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7787 sec = elf_fini_array_section;
7790 return sec;
7793 /* Use .init_array section for constructors. */
7795 void
7796 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7798 section *sec = get_elf_initfini_array_priority_section (priority,
7799 true);
7800 assemble_addr_to_section (symbol, sec);
7803 /* Use .fini_array section for destructors. */
7805 void
7806 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7808 section *sec = get_elf_initfini_array_priority_section (priority,
7809 false);
7810 assemble_addr_to_section (symbol, sec);
7813 /* Default TARGET_ASM_OUTPUT_IDENT hook.
7815 This is a bit of a cheat. The real default is a no-op, but this
7816 hook is the default for all targets with a .ident directive. */
7818 void
7819 default_asm_output_ident_directive (const char *ident_str)
7821 const char *ident_asm_op = "\t.ident\t";
7823 /* If we are still in the front end, do not write out the string
7824 to asm_out_file. Instead, add a fake top-level asm statement.
7825 This allows the front ends to use this hook without actually
7826 writing to asm_out_file, to handle #ident or Pragma Ident. */
7827 if (symtab->state == PARSING)
7829 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
7830 symtab->finalize_toplevel_asm (build_string (strlen (buf), buf));
7832 else
7833 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
7837 /* This function ensures that vtable_map variables are not only
7838 in the comdat section, but that each variable has its own unique
7839 comdat name. Without this the variables end up in the same section
7840 with a single comdat name.
7842 FIXME: resolve_unique_section needs to deal better with
7843 decls with both DECL_SECTION_NAME and DECL_ONE_ONLY. Once
7844 that is fixed, this if-else statement can be replaced with
7845 a single call to "switch_to_section (sect)". */
7847 static void
7848 handle_vtv_comdat_section (section *sect, const_tree decl ATTRIBUTE_UNUSED)
7850 #if defined (OBJECT_FORMAT_ELF)
7851 targetm.asm_out.named_section (sect->named.name,
7852 sect->named.common.flags
7853 | SECTION_LINKONCE,
7854 DECL_NAME (decl));
7855 in_section = sect;
7856 #else
7857 /* Neither OBJECT_FORMAT_PE, nor OBJECT_FORMAT_COFF is set here.
7858 Therefore the following check is used.
7859 In case a the target is PE or COFF a comdat group section
7860 is created, e.g. .vtable_map_vars$foo. The linker places
7861 everything in .vtable_map_vars at the end.
7863 A fix could be made in
7864 gcc/config/i386/winnt.c: i386_pe_unique_section. */
7865 if (TARGET_PECOFF)
7867 char *name;
7869 if (TREE_CODE (DECL_NAME (decl)) == IDENTIFIER_NODE)
7870 name = ACONCAT ((sect->named.name, "$",
7871 IDENTIFIER_POINTER (DECL_NAME (decl)), NULL));
7872 else
7873 name = ACONCAT ((sect->named.name, "$",
7874 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (DECL_NAME (decl))),
7875 NULL));
7877 targetm.asm_out.named_section (name,
7878 sect->named.common.flags
7879 | SECTION_LINKONCE,
7880 DECL_NAME (decl));
7881 in_section = sect;
7883 else
7884 switch_to_section (sect);
7885 #endif
7888 #include "gt-varasm.h"