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[official-gcc.git] / gcc / varasm.c
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1 /* Output variables, constants and external declarations, for GNU compiler.
2 Copyright (C) 1987-2017 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 ("%+qD causes a section type conflict with %qD",
324 decl, sect->named.decl);
325 else
326 error ("section type conflict with %qD", 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 ("%+qD 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 (DECL_SECTION_NAME (decl))
1675 struct cgraph_node *node = cgraph_node::get (current_function_decl);
1676 /* Calls to function_section rely on first_function_block_is_cold
1677 being accurate. */
1678 first_function_block_is_cold = (node
1679 && node->frequency
1680 == NODE_FREQUENCY_UNLIKELY_EXECUTED);
1683 in_cold_section_p = first_function_block_is_cold;
1686 /* Get the function's name, as described by its RTL. This may be
1687 different from the DECL_NAME name used in the source file. */
1688 const char *
1689 get_fnname_from_decl (tree decl)
1691 rtx x = DECL_RTL (decl);
1692 gcc_assert (MEM_P (x));
1693 x = XEXP (x, 0);
1694 gcc_assert (GET_CODE (x) == SYMBOL_REF);
1695 return XSTR (x, 0);
1698 /* Output assembler code for the constant pool of a function and associated
1699 with defining the name of the function. DECL describes the function.
1700 NAME is the function's name. For the constant pool, we use the current
1701 constant pool data. */
1703 void
1704 assemble_start_function (tree decl, const char *fnname)
1706 int align;
1707 char tmp_label[100];
1708 bool hot_label_written = false;
1710 if (crtl->has_bb_partition)
1712 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTB", const_labelno);
1713 crtl->subsections.hot_section_label = ggc_strdup (tmp_label);
1714 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDB", const_labelno);
1715 crtl->subsections.cold_section_label = ggc_strdup (tmp_label);
1716 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTE", const_labelno);
1717 crtl->subsections.hot_section_end_label = ggc_strdup (tmp_label);
1718 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDE", const_labelno);
1719 crtl->subsections.cold_section_end_label = ggc_strdup (tmp_label);
1720 const_labelno++;
1721 cold_function_name = NULL_TREE;
1723 else
1725 crtl->subsections.hot_section_label = NULL;
1726 crtl->subsections.cold_section_label = NULL;
1727 crtl->subsections.hot_section_end_label = NULL;
1728 crtl->subsections.cold_section_end_label = NULL;
1731 /* The following code does not need preprocessing in the assembler. */
1733 app_disable ();
1735 if (CONSTANT_POOL_BEFORE_FUNCTION)
1736 output_constant_pool (fnname, decl);
1738 align = symtab_node::get (decl)->definition_alignment ();
1740 /* Make sure the not and cold text (code) sections are properly
1741 aligned. This is necessary here in the case where the function
1742 has both hot and cold sections, because we don't want to re-set
1743 the alignment when the section switch happens mid-function. */
1745 if (crtl->has_bb_partition)
1747 first_function_block_is_cold = false;
1749 switch_to_section (unlikely_text_section ());
1750 assemble_align (align);
1751 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_label);
1753 /* When the function starts with a cold section, we need to explicitly
1754 align the hot section and write out the hot section label.
1755 But if the current function is a thunk, we do not have a CFG. */
1756 if (!cfun->is_thunk
1757 && BB_PARTITION (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) == BB_COLD_PARTITION)
1759 switch_to_section (text_section);
1760 assemble_align (align);
1761 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1762 hot_label_written = true;
1763 first_function_block_is_cold = true;
1765 in_cold_section_p = first_function_block_is_cold;
1769 /* Switch to the correct text section for the start of the function. */
1771 switch_to_section (function_section (decl));
1772 if (crtl->has_bb_partition && !hot_label_written)
1773 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1775 /* Tell assembler to move to target machine's alignment for functions. */
1776 align = floor_log2 (align / BITS_PER_UNIT);
1777 if (align > 0)
1779 ASM_OUTPUT_ALIGN (asm_out_file, align);
1782 /* Handle a user-specified function alignment.
1783 Note that we still need to align to DECL_ALIGN, as above,
1784 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1785 if (! DECL_USER_ALIGN (decl)
1786 && align_functions_log > align
1787 && optimize_function_for_speed_p (cfun))
1789 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1790 int align_log = align_functions_log;
1791 #endif
1792 int max_skip = align_functions - 1;
1793 if (flag_limit_function_alignment && crtl->max_insn_address > 0
1794 && max_skip >= crtl->max_insn_address)
1795 max_skip = crtl->max_insn_address - 1;
1797 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1798 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file, align_log, max_skip);
1799 #else
1800 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1801 #endif
1804 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1805 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1806 #endif
1808 if (!DECL_IGNORED_P (decl))
1809 (*debug_hooks->begin_function) (decl);
1811 /* Make function name accessible from other files, if appropriate. */
1813 if (TREE_PUBLIC (decl)
1814 || (cgraph_node::get (decl)->instrumentation_clone
1815 && cgraph_node::get (decl)->instrumented_version
1816 && TREE_PUBLIC (cgraph_node::get (decl)->instrumented_version->decl)))
1818 notice_global_symbol (decl);
1820 globalize_decl (decl);
1822 maybe_assemble_visibility (decl);
1825 if (DECL_PRESERVE_P (decl))
1826 targetm.asm_out.mark_decl_preserved (fnname);
1828 unsigned HOST_WIDE_INT patch_area_size = function_entry_patch_area_size;
1829 unsigned HOST_WIDE_INT patch_area_entry = function_entry_patch_area_start;
1831 tree patchable_function_entry_attr
1832 = lookup_attribute ("patchable_function_entry", DECL_ATTRIBUTES (decl));
1833 if (patchable_function_entry_attr)
1835 tree pp_val = TREE_VALUE (patchable_function_entry_attr);
1836 tree patchable_function_entry_value1 = TREE_VALUE (pp_val);
1838 if (tree_fits_uhwi_p (patchable_function_entry_value1))
1839 patch_area_size = tree_to_uhwi (patchable_function_entry_value1);
1840 else
1841 gcc_unreachable ();
1843 patch_area_entry = 0;
1844 if (list_length (pp_val) > 1)
1846 tree patchable_function_entry_value2 =
1847 TREE_VALUE (TREE_CHAIN (pp_val));
1849 if (tree_fits_uhwi_p (patchable_function_entry_value2))
1850 patch_area_entry = tree_to_uhwi (patchable_function_entry_value2);
1851 else
1852 gcc_unreachable ();
1856 if (patch_area_entry > patch_area_size)
1858 if (patch_area_size > 0)
1859 warning (OPT_Wattributes, "Patchable function entry > size");
1860 patch_area_entry = 0;
1863 /* Emit the patching area before the entry label, if any. */
1864 if (patch_area_entry > 0)
1865 targetm.asm_out.print_patchable_function_entry (asm_out_file,
1866 patch_area_entry, true);
1868 /* Do any machine/system dependent processing of the function name. */
1869 #ifdef ASM_DECLARE_FUNCTION_NAME
1870 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1871 #else
1872 /* Standard thing is just output label for the function. */
1873 ASM_OUTPUT_FUNCTION_LABEL (asm_out_file, fnname, current_function_decl);
1874 #endif /* ASM_DECLARE_FUNCTION_NAME */
1876 /* And the area after the label. Record it if we haven't done so yet. */
1877 if (patch_area_size > patch_area_entry)
1878 targetm.asm_out.print_patchable_function_entry (asm_out_file,
1879 patch_area_size-patch_area_entry,
1880 patch_area_entry == 0);
1882 if (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (decl)))
1883 saw_no_split_stack = true;
1886 /* Output assembler code associated with defining the size of the
1887 function. DECL describes the function. NAME is the function's name. */
1889 void
1890 assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED)
1892 #ifdef ASM_DECLARE_FUNCTION_SIZE
1893 /* We could have switched section in the middle of the function. */
1894 if (crtl->has_bb_partition)
1895 switch_to_section (function_section (decl));
1896 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1897 #endif
1898 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1900 output_constant_pool (fnname, decl);
1901 switch_to_section (function_section (decl)); /* need to switch back */
1903 /* Output labels for end of hot/cold text sections (to be used by
1904 debug info.) */
1905 if (crtl->has_bb_partition)
1907 section *save_text_section;
1909 save_text_section = in_section;
1910 switch_to_section (unlikely_text_section ());
1911 #ifdef ASM_DECLARE_COLD_FUNCTION_SIZE
1912 if (cold_function_name != NULL_TREE)
1913 ASM_DECLARE_COLD_FUNCTION_SIZE (asm_out_file,
1914 IDENTIFIER_POINTER (cold_function_name),
1915 decl);
1916 #endif
1917 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label);
1918 if (first_function_block_is_cold)
1919 switch_to_section (text_section);
1920 else
1921 switch_to_section (function_section (decl));
1922 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label);
1923 switch_to_section (save_text_section);
1927 /* Assemble code to leave SIZE bytes of zeros. */
1929 void
1930 assemble_zeros (unsigned HOST_WIDE_INT size)
1932 /* Do no output if -fsyntax-only. */
1933 if (flag_syntax_only)
1934 return;
1936 #ifdef ASM_NO_SKIP_IN_TEXT
1937 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1938 so we must output 0s explicitly in the text section. */
1939 if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0)
1941 unsigned HOST_WIDE_INT i;
1942 for (i = 0; i < size; i++)
1943 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1945 else
1946 #endif
1947 if (size > 0)
1948 ASM_OUTPUT_SKIP (asm_out_file, size);
1951 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1953 void
1954 assemble_align (int align)
1956 if (align > BITS_PER_UNIT)
1958 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1962 /* Assemble a string constant with the specified C string as contents. */
1964 void
1965 assemble_string (const char *p, int size)
1967 int pos = 0;
1968 int maximum = 2000;
1970 /* If the string is very long, split it up. */
1972 while (pos < size)
1974 int thissize = size - pos;
1975 if (thissize > maximum)
1976 thissize = maximum;
1978 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1980 pos += thissize;
1981 p += thissize;
1986 /* A noswitch_section_callback for lcomm_section. */
1988 static bool
1989 emit_local (tree decl ATTRIBUTE_UNUSED,
1990 const char *name ATTRIBUTE_UNUSED,
1991 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1992 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1994 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1995 unsigned int align = symtab_node::get (decl)->definition_alignment ();
1996 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name,
1997 size, align);
1998 return true;
1999 #elif defined ASM_OUTPUT_ALIGNED_LOCAL
2000 unsigned int align = symtab_node::get (decl)->definition_alignment ();
2001 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, align);
2002 return true;
2003 #else
2004 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2005 return false;
2006 #endif
2009 /* A noswitch_section_callback for bss_noswitch_section. */
2011 #if defined ASM_OUTPUT_ALIGNED_BSS
2012 static bool
2013 emit_bss (tree decl ATTRIBUTE_UNUSED,
2014 const char *name ATTRIBUTE_UNUSED,
2015 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2016 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2018 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size,
2019 get_variable_align (decl));
2020 return true;
2022 #endif
2024 /* A noswitch_section_callback for comm_section. */
2026 static bool
2027 emit_common (tree decl ATTRIBUTE_UNUSED,
2028 const char *name ATTRIBUTE_UNUSED,
2029 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2030 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2032 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
2033 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name,
2034 size, get_variable_align (decl));
2035 return true;
2036 #elif defined ASM_OUTPUT_ALIGNED_COMMON
2037 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size,
2038 get_variable_align (decl));
2039 return true;
2040 #else
2041 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
2042 return false;
2043 #endif
2046 /* A noswitch_section_callback for tls_comm_section. */
2048 static bool
2049 emit_tls_common (tree decl ATTRIBUTE_UNUSED,
2050 const char *name ATTRIBUTE_UNUSED,
2051 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2052 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2054 #ifdef ASM_OUTPUT_TLS_COMMON
2055 ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size);
2056 return true;
2057 #else
2058 sorry ("thread-local COMMON data not implemented");
2059 return true;
2060 #endif
2063 /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT.
2064 NAME is the name of DECL's SYMBOL_REF. */
2066 static void
2067 assemble_noswitch_variable (tree decl, const char *name, section *sect,
2068 unsigned int align)
2070 unsigned HOST_WIDE_INT size, rounded;
2072 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2073 rounded = size;
2075 if ((flag_sanitize & SANITIZE_ADDRESS) && asan_protect_global (decl))
2076 size += asan_red_zone_size (size);
2078 /* Don't allocate zero bytes of common,
2079 since that means "undefined external" in the linker. */
2080 if (size == 0)
2081 rounded = 1;
2083 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2084 so that each uninitialized object starts on such a boundary. */
2085 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
2086 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2087 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2089 if (!sect->noswitch.callback (decl, name, size, rounded)
2090 && (unsigned HOST_WIDE_INT) (align / BITS_PER_UNIT) > rounded)
2091 error ("requested alignment for %q+D is greater than "
2092 "implemented alignment of %wu", decl, rounded);
2095 /* A subroutine of assemble_variable. Output the label and contents of
2096 DECL, whose address is a SYMBOL_REF with name NAME. DONT_OUTPUT_DATA
2097 is as for assemble_variable. */
2099 static void
2100 assemble_variable_contents (tree decl, const char *name,
2101 bool dont_output_data)
2103 /* Do any machine/system dependent processing of the object. */
2104 #ifdef ASM_DECLARE_OBJECT_NAME
2105 last_assemble_variable_decl = decl;
2106 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
2107 #else
2108 /* Standard thing is just output label for the object. */
2109 ASM_OUTPUT_LABEL (asm_out_file, name);
2110 #endif /* ASM_DECLARE_OBJECT_NAME */
2112 if (!dont_output_data)
2114 /* Caller is supposed to use varpool_get_constructor when it wants
2115 to output the body. */
2116 gcc_assert (!in_lto_p || DECL_INITIAL (decl) != error_mark_node);
2117 if (DECL_INITIAL (decl)
2118 && DECL_INITIAL (decl) != error_mark_node
2119 && !initializer_zerop (DECL_INITIAL (decl)))
2120 /* Output the actual data. */
2121 output_constant (DECL_INITIAL (decl),
2122 tree_to_uhwi (DECL_SIZE_UNIT (decl)),
2123 get_variable_align (decl),
2124 false);
2125 else
2126 /* Leave space for it. */
2127 assemble_zeros (tree_to_uhwi (DECL_SIZE_UNIT (decl)));
2128 targetm.asm_out.decl_end ();
2132 /* Write out assembly for the variable DECL, which is not defined in
2133 the current translation unit. */
2134 void
2135 assemble_undefined_decl (tree decl)
2137 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
2138 targetm.asm_out.assemble_undefined_decl (asm_out_file, name, decl);
2141 /* Assemble everything that is needed for a variable or function declaration.
2142 Not used for automatic variables, and not used for function definitions.
2143 Should not be called for variables of incomplete structure type.
2145 TOP_LEVEL is nonzero if this variable has file scope.
2146 AT_END is nonzero if this is the special handling, at end of compilation,
2147 to define things that have had only tentative definitions.
2148 DONT_OUTPUT_DATA if nonzero means don't actually output the
2149 initial value (that will be done by the caller). */
2151 void
2152 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
2153 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
2155 const char *name;
2156 rtx decl_rtl, symbol;
2157 section *sect;
2158 unsigned int align;
2159 bool asan_protected = false;
2161 /* This function is supposed to handle VARIABLES. Ensure we have one. */
2162 gcc_assert (VAR_P (decl));
2164 /* Emulated TLS had better not get this far. */
2165 gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl));
2167 last_assemble_variable_decl = 0;
2169 /* Normally no need to say anything here for external references,
2170 since assemble_external is called by the language-specific code
2171 when a declaration is first seen. */
2173 if (DECL_EXTERNAL (decl))
2174 return;
2176 /* Do nothing for global register variables. */
2177 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
2179 TREE_ASM_WRITTEN (decl) = 1;
2180 return;
2183 /* If type was incomplete when the variable was declared,
2184 see if it is complete now. */
2186 if (DECL_SIZE (decl) == 0)
2187 layout_decl (decl, 0);
2189 /* Still incomplete => don't allocate it; treat the tentative defn
2190 (which is what it must have been) as an `extern' reference. */
2192 if (!dont_output_data && DECL_SIZE (decl) == 0)
2194 error ("storage size of %q+D isn%'t known", decl);
2195 TREE_ASM_WRITTEN (decl) = 1;
2196 return;
2199 /* The first declaration of a variable that comes through this function
2200 decides whether it is global (in C, has external linkage)
2201 or local (in C, has internal linkage). So do nothing more
2202 if this function has already run. */
2204 if (TREE_ASM_WRITTEN (decl))
2205 return;
2207 /* Make sure targetm.encode_section_info is invoked before we set
2208 ASM_WRITTEN. */
2209 decl_rtl = DECL_RTL (decl);
2211 TREE_ASM_WRITTEN (decl) = 1;
2213 /* Do no output if -fsyntax-only. */
2214 if (flag_syntax_only)
2215 return;
2217 if (! dont_output_data
2218 && ! valid_constant_size_p (DECL_SIZE_UNIT (decl)))
2220 error ("size of variable %q+D is too large", decl);
2221 return;
2224 gcc_assert (MEM_P (decl_rtl));
2225 gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF);
2226 symbol = XEXP (decl_rtl, 0);
2228 /* If this symbol belongs to the tree constant pool, output the constant
2229 if it hasn't already been written. */
2230 if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
2232 tree decl = SYMBOL_REF_DECL (symbol);
2233 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
2234 output_constant_def_contents (symbol);
2235 return;
2238 app_disable ();
2240 name = XSTR (symbol, 0);
2241 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
2242 notice_global_symbol (decl);
2244 /* Compute the alignment of this data. */
2246 align_variable (decl, dont_output_data);
2248 if ((flag_sanitize & SANITIZE_ADDRESS)
2249 && asan_protect_global (decl))
2251 asan_protected = true;
2252 SET_DECL_ALIGN (decl, MAX (DECL_ALIGN (decl),
2253 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT));
2256 set_mem_align (decl_rtl, DECL_ALIGN (decl));
2258 align = get_variable_align (decl);
2260 if (TREE_PUBLIC (decl))
2261 maybe_assemble_visibility (decl);
2263 if (DECL_PRESERVE_P (decl))
2264 targetm.asm_out.mark_decl_preserved (name);
2266 /* First make the assembler name(s) global if appropriate. */
2267 sect = get_variable_section (decl, false);
2268 if (TREE_PUBLIC (decl)
2269 && (sect->common.flags & SECTION_COMMON) == 0)
2270 globalize_decl (decl);
2272 /* Output any data that we will need to use the address of. */
2273 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
2274 output_addressed_constants (DECL_INITIAL (decl));
2276 /* dbxout.c needs to know this. */
2277 if (sect && (sect->common.flags & SECTION_CODE) != 0)
2278 DECL_IN_TEXT_SECTION (decl) = 1;
2280 /* If the decl is part of an object_block, make sure that the decl
2281 has been positioned within its block, but do not write out its
2282 definition yet. output_object_blocks will do that later. */
2283 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
2285 gcc_assert (!dont_output_data);
2286 place_block_symbol (symbol);
2288 else if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
2289 assemble_noswitch_variable (decl, name, sect, align);
2290 else
2292 /* Special-case handling of vtv comdat sections. */
2293 if (sect->named.name
2294 && (strcmp (sect->named.name, ".vtable_map_vars") == 0))
2295 handle_vtv_comdat_section (sect, decl);
2296 else
2297 switch_to_section (sect);
2298 if (align > BITS_PER_UNIT)
2299 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2300 assemble_variable_contents (decl, name, dont_output_data);
2301 if (asan_protected)
2303 unsigned HOST_WIDE_INT int size
2304 = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2305 assemble_zeros (asan_red_zone_size (size));
2311 /* Given a function declaration (FN_DECL), this function assembles the
2312 function into the .preinit_array section. */
2314 void
2315 assemble_vtv_preinit_initializer (tree fn_decl)
2317 section *sect;
2318 unsigned flags = SECTION_WRITE;
2319 rtx symbol = XEXP (DECL_RTL (fn_decl), 0);
2321 flags |= SECTION_NOTYPE;
2322 sect = get_section (".preinit_array", flags, fn_decl);
2323 switch_to_section (sect);
2324 assemble_addr_to_section (symbol, sect);
2327 /* Return 1 if type TYPE contains any pointers. */
2329 static int
2330 contains_pointers_p (tree type)
2332 switch (TREE_CODE (type))
2334 case POINTER_TYPE:
2335 case REFERENCE_TYPE:
2336 /* I'm not sure whether OFFSET_TYPE needs this treatment,
2337 so I'll play safe and return 1. */
2338 case OFFSET_TYPE:
2339 return 1;
2341 case RECORD_TYPE:
2342 case UNION_TYPE:
2343 case QUAL_UNION_TYPE:
2345 tree fields;
2346 /* For a type that has fields, see if the fields have pointers. */
2347 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2348 if (TREE_CODE (fields) == FIELD_DECL
2349 && contains_pointers_p (TREE_TYPE (fields)))
2350 return 1;
2351 return 0;
2354 case ARRAY_TYPE:
2355 /* An array type contains pointers if its element type does. */
2356 return contains_pointers_p (TREE_TYPE (type));
2358 default:
2359 return 0;
2363 /* We delay assemble_external processing until
2364 the compilation unit is finalized. This is the best we can do for
2365 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2366 it all the way to final. See PR 17982 for further discussion. */
2367 static GTY(()) tree pending_assemble_externals;
2369 #ifdef ASM_OUTPUT_EXTERNAL
2370 /* Some targets delay some output to final using TARGET_ASM_FILE_END.
2371 As a result, assemble_external can be called after the list of externals
2372 is processed and the pointer set destroyed. */
2373 static bool pending_assemble_externals_processed;
2375 /* Avoid O(external_decls**2) lookups in the pending_assemble_externals
2376 TREE_LIST in assemble_external. */
2377 static hash_set<tree> *pending_assemble_externals_set;
2379 /* True if DECL is a function decl for which no out-of-line copy exists.
2380 It is assumed that DECL's assembler name has been set. */
2382 static bool
2383 incorporeal_function_p (tree decl)
2385 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
2387 const char *name;
2389 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2390 && (DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA
2391 || DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA_WITH_ALIGN))
2392 return true;
2394 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2395 /* Atomic or sync builtins which have survived this far will be
2396 resolved externally and therefore are not incorporeal. */
2397 if (strncmp (name, "__builtin_", 10) == 0)
2398 return true;
2400 return false;
2403 /* Actually do the tests to determine if this is necessary, and invoke
2404 ASM_OUTPUT_EXTERNAL. */
2405 static void
2406 assemble_external_real (tree decl)
2408 rtx rtl = DECL_RTL (decl);
2410 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2411 && !SYMBOL_REF_USED (XEXP (rtl, 0))
2412 && !incorporeal_function_p (decl))
2414 /* Some systems do require some output. */
2415 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2416 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2419 #endif
2421 void
2422 process_pending_assemble_externals (void)
2424 #ifdef ASM_OUTPUT_EXTERNAL
2425 tree list;
2426 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2427 assemble_external_real (TREE_VALUE (list));
2429 pending_assemble_externals = 0;
2430 pending_assemble_externals_processed = true;
2431 delete pending_assemble_externals_set;
2432 #endif
2435 /* This TREE_LIST contains any weak symbol declarations waiting
2436 to be emitted. */
2437 static GTY(()) tree weak_decls;
2439 /* Output something to declare an external symbol to the assembler,
2440 and qualifiers such as weakness. (Most assemblers don't need
2441 extern declaration, so we normally output nothing.) Do nothing if
2442 DECL is not external. */
2444 void
2445 assemble_external (tree decl ATTRIBUTE_UNUSED)
2447 /* Make sure that the ASM_OUT_FILE is open.
2448 If it's not, we should not be calling this function. */
2449 gcc_assert (asm_out_file);
2451 /* In a perfect world, the following condition would be true.
2452 Sadly, the Go front end emit assembly *from the front end*,
2453 bypassing the call graph. See PR52739. Fix before GCC 4.8. */
2454 #if 0
2455 /* This function should only be called if we are expanding, or have
2456 expanded, to RTL.
2457 Ideally, only final.c would be calling this function, but it is
2458 not clear whether that would break things somehow. See PR 17982
2459 for further discussion. */
2460 gcc_assert (state == EXPANSION
2461 || state == FINISHED);
2462 #endif
2464 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2465 return;
2467 /* We want to output annotation for weak and external symbols at
2468 very last to check if they are references or not. */
2470 if (TARGET_SUPPORTS_WEAK
2471 && DECL_WEAK (decl)
2472 /* TREE_STATIC is a weird and abused creature which is not
2473 generally the right test for whether an entity has been
2474 locally emitted, inlined or otherwise not-really-extern, but
2475 for declarations that can be weak, it happens to be
2476 match. */
2477 && !TREE_STATIC (decl)
2478 && lookup_attribute ("weak", DECL_ATTRIBUTES (decl))
2479 && value_member (decl, weak_decls) == NULL_TREE)
2480 weak_decls = tree_cons (NULL, decl, weak_decls);
2482 #ifdef ASM_OUTPUT_EXTERNAL
2483 if (pending_assemble_externals_processed)
2485 assemble_external_real (decl);
2486 return;
2489 if (! pending_assemble_externals_set->add (decl))
2490 pending_assemble_externals = tree_cons (NULL, decl,
2491 pending_assemble_externals);
2492 #endif
2495 /* Similar, for calling a library function FUN. */
2497 void
2498 assemble_external_libcall (rtx fun)
2500 /* Declare library function name external when first used, if nec. */
2501 if (! SYMBOL_REF_USED (fun))
2503 SYMBOL_REF_USED (fun) = 1;
2504 targetm.asm_out.external_libcall (fun);
2508 /* Assemble a label named NAME. */
2510 void
2511 assemble_label (FILE *file, const char *name)
2513 ASM_OUTPUT_LABEL (file, name);
2516 /* Set the symbol_referenced flag for ID. */
2517 void
2518 mark_referenced (tree id)
2520 TREE_SYMBOL_REFERENCED (id) = 1;
2523 /* Set the symbol_referenced flag for DECL and notify callgraph. */
2524 void
2525 mark_decl_referenced (tree decl)
2527 if (TREE_CODE (decl) == FUNCTION_DECL)
2529 /* Extern inline functions don't become needed when referenced.
2530 If we know a method will be emitted in other TU and no new
2531 functions can be marked reachable, just use the external
2532 definition. */
2533 struct cgraph_node *node = cgraph_node::get_create (decl);
2534 if (!DECL_EXTERNAL (decl)
2535 && !node->definition)
2536 node->mark_force_output ();
2538 else if (VAR_P (decl))
2540 varpool_node *node = varpool_node::get_create (decl);
2541 /* C++ frontend use mark_decl_references to force COMDAT variables
2542 to be output that might appear dead otherwise. */
2543 node->force_output = true;
2545 /* else do nothing - we can get various sorts of CST nodes here,
2546 which do not need to be marked. */
2550 /* Output to FILE (an assembly file) a reference to NAME. If NAME
2551 starts with a *, the rest of NAME is output verbatim. Otherwise
2552 NAME is transformed in a target-specific way (usually by the
2553 addition of an underscore). */
2555 void
2556 assemble_name_raw (FILE *file, const char *name)
2558 if (name[0] == '*')
2559 fputs (&name[1], file);
2560 else
2561 ASM_OUTPUT_LABELREF (file, name);
2564 /* Like assemble_name_raw, but should be used when NAME might refer to
2565 an entity that is also represented as a tree (like a function or
2566 variable). If NAME does refer to such an entity, that entity will
2567 be marked as referenced. */
2569 void
2570 assemble_name (FILE *file, const char *name)
2572 const char *real_name;
2573 tree id;
2575 real_name = targetm.strip_name_encoding (name);
2577 id = maybe_get_identifier (real_name);
2578 if (id)
2580 tree id_orig = id;
2582 mark_referenced (id);
2583 ultimate_transparent_alias_target (&id);
2584 if (id != id_orig)
2585 name = IDENTIFIER_POINTER (id);
2586 gcc_assert (! TREE_CHAIN (id));
2589 assemble_name_raw (file, name);
2592 /* Allocate SIZE bytes writable static space with a gensym name
2593 and return an RTX to refer to its address. */
2596 assemble_static_space (unsigned HOST_WIDE_INT size)
2598 char name[17];
2599 const char *namestring;
2600 rtx x;
2602 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2603 ++const_labelno;
2604 namestring = ggc_strdup (name);
2606 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2607 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2609 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2610 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2611 BIGGEST_ALIGNMENT);
2612 #else
2613 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2614 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2615 #else
2617 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2618 so that each uninitialized object starts on such a boundary. */
2619 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2620 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2621 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2622 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2623 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2624 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2626 #endif
2627 #endif
2628 return x;
2631 /* Assemble the static constant template for function entry trampolines.
2632 This is done at most once per compilation.
2633 Returns an RTX for the address of the template. */
2635 static GTY(()) rtx initial_trampoline;
2638 assemble_trampoline_template (void)
2640 char label[256];
2641 const char *name;
2642 int align;
2643 rtx symbol;
2645 gcc_assert (targetm.asm_out.trampoline_template != NULL);
2647 if (initial_trampoline)
2648 return initial_trampoline;
2650 /* By default, put trampoline templates in read-only data section. */
2652 #ifdef TRAMPOLINE_SECTION
2653 switch_to_section (TRAMPOLINE_SECTION);
2654 #else
2655 switch_to_section (readonly_data_section);
2656 #endif
2658 /* Write the assembler code to define one. */
2659 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2660 if (align > 0)
2661 ASM_OUTPUT_ALIGN (asm_out_file, align);
2663 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2664 targetm.asm_out.trampoline_template (asm_out_file);
2666 /* Record the rtl to refer to it. */
2667 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2668 name = ggc_strdup (label);
2669 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2670 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2672 initial_trampoline = gen_const_mem (BLKmode, symbol);
2673 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2674 set_mem_size (initial_trampoline, TRAMPOLINE_SIZE);
2676 return initial_trampoline;
2679 /* A and B are either alignments or offsets. Return the minimum alignment
2680 that may be assumed after adding the two together. */
2682 static inline unsigned
2683 min_align (unsigned int a, unsigned int b)
2685 return least_bit_hwi (a | b);
2688 /* Return the assembler directive for creating a given kind of integer
2689 object. SIZE is the number of bytes in the object and ALIGNED_P
2690 indicates whether it is known to be aligned. Return NULL if the
2691 assembly dialect has no such directive.
2693 The returned string should be printed at the start of a new line and
2694 be followed immediately by the object's initial value. */
2696 const char *
2697 integer_asm_op (int size, int aligned_p)
2699 struct asm_int_op *ops;
2701 if (aligned_p)
2702 ops = &targetm.asm_out.aligned_op;
2703 else
2704 ops = &targetm.asm_out.unaligned_op;
2706 switch (size)
2708 case 1:
2709 return targetm.asm_out.byte_op;
2710 case 2:
2711 return ops->hi;
2712 case 4:
2713 return ops->si;
2714 case 8:
2715 return ops->di;
2716 case 16:
2717 return ops->ti;
2718 default:
2719 return NULL;
2723 /* Use directive OP to assemble an integer object X. Print OP at the
2724 start of the line, followed immediately by the value of X. */
2726 void
2727 assemble_integer_with_op (const char *op, rtx x)
2729 fputs (op, asm_out_file);
2730 output_addr_const (asm_out_file, x);
2731 fputc ('\n', asm_out_file);
2734 /* The default implementation of the asm_out.integer target hook. */
2736 bool
2737 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2738 unsigned int size ATTRIBUTE_UNUSED,
2739 int aligned_p ATTRIBUTE_UNUSED)
2741 const char *op = integer_asm_op (size, aligned_p);
2742 /* Avoid GAS bugs for large values. Specifically negative values whose
2743 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2744 if (size > UNITS_PER_WORD && size > POINTER_SIZE_UNITS)
2745 return false;
2746 return op && (assemble_integer_with_op (op, x), true);
2749 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2750 the alignment of the integer in bits. Return 1 if we were able to output
2751 the constant, otherwise 0. We must be able to output the constant,
2752 if FORCE is nonzero. */
2754 bool
2755 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2757 int aligned_p;
2759 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2761 /* See if the target hook can handle this kind of object. */
2762 if (targetm.asm_out.integer (x, size, aligned_p))
2763 return true;
2765 /* If the object is a multi-byte one, try splitting it up. Split
2766 it into words it if is multi-word, otherwise split it into bytes. */
2767 if (size > 1)
2769 machine_mode omode, imode;
2770 unsigned int subalign;
2771 unsigned int subsize, i;
2772 enum mode_class mclass;
2774 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2775 subalign = MIN (align, subsize * BITS_PER_UNIT);
2776 if (GET_CODE (x) == CONST_FIXED)
2777 mclass = GET_MODE_CLASS (GET_MODE (x));
2778 else
2779 mclass = MODE_INT;
2781 omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0);
2782 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0);
2784 for (i = 0; i < size; i += subsize)
2786 rtx partial = simplify_subreg (omode, x, imode, i);
2787 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2788 break;
2790 if (i == size)
2791 return true;
2793 /* If we've printed some of it, but not all of it, there's no going
2794 back now. */
2795 gcc_assert (!i);
2798 gcc_assert (!force);
2800 return false;
2803 /* Assemble the floating-point constant D into an object of size MODE. ALIGN
2804 is the alignment of the constant in bits. If REVERSE is true, D is output
2805 in reverse storage order. */
2807 void
2808 assemble_real (REAL_VALUE_TYPE d, machine_mode mode, unsigned int align,
2809 bool reverse)
2811 long data[4] = {0, 0, 0, 0};
2812 int bitsize, nelts, nunits, units_per;
2813 rtx elt;
2815 /* This is hairy. We have a quantity of known size. real_to_target
2816 will put it into an array of *host* longs, 32 bits per element
2817 (even if long is more than 32 bits). We need to determine the
2818 number of array elements that are occupied (nelts) and the number
2819 of *target* min-addressable units that will be occupied in the
2820 object file (nunits). We cannot assume that 32 divides the
2821 mode's bitsize (size * BITS_PER_UNIT) evenly.
2823 size * BITS_PER_UNIT is used here to make sure that padding bits
2824 (which might appear at either end of the value; real_to_target
2825 will include the padding bits in its output array) are included. */
2827 nunits = GET_MODE_SIZE (mode);
2828 bitsize = nunits * BITS_PER_UNIT;
2829 nelts = CEIL (bitsize, 32);
2830 units_per = 32 / BITS_PER_UNIT;
2832 real_to_target (data, &d, mode);
2834 /* Put out the first word with the specified alignment. */
2835 if (reverse)
2836 elt = flip_storage_order (SImode, gen_int_mode (data[nelts - 1], SImode));
2837 else
2838 elt = GEN_INT (data[0]);
2839 assemble_integer (elt, MIN (nunits, units_per), align, 1);
2840 nunits -= units_per;
2842 /* Subsequent words need only 32-bit alignment. */
2843 align = min_align (align, 32);
2845 for (int i = 1; i < nelts; i++)
2847 if (reverse)
2848 elt = flip_storage_order (SImode,
2849 gen_int_mode (data[nelts - 1 - i], SImode));
2850 else
2851 elt = GEN_INT (data[i]);
2852 assemble_integer (elt, MIN (nunits, units_per), align, 1);
2853 nunits -= units_per;
2857 /* Given an expression EXP with a constant value,
2858 reduce it to the sum of an assembler symbol and an integer.
2859 Store them both in the structure *VALUE.
2860 EXP must be reducible. */
2862 struct addr_const {
2863 rtx base;
2864 HOST_WIDE_INT offset;
2867 static void
2868 decode_addr_const (tree exp, struct addr_const *value)
2870 tree target = TREE_OPERAND (exp, 0);
2871 int offset = 0;
2872 rtx x;
2874 while (1)
2876 if (TREE_CODE (target) == COMPONENT_REF
2877 && tree_fits_shwi_p (byte_position (TREE_OPERAND (target, 1))))
2879 offset += int_byte_position (TREE_OPERAND (target, 1));
2880 target = TREE_OPERAND (target, 0);
2882 else if (TREE_CODE (target) == ARRAY_REF
2883 || TREE_CODE (target) == ARRAY_RANGE_REF)
2885 offset += (tree_to_uhwi (TYPE_SIZE_UNIT (TREE_TYPE (target)))
2886 * tree_to_shwi (TREE_OPERAND (target, 1)));
2887 target = TREE_OPERAND (target, 0);
2889 else if (TREE_CODE (target) == MEM_REF
2890 && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR)
2892 offset += mem_ref_offset (target).to_short_addr ();
2893 target = TREE_OPERAND (TREE_OPERAND (target, 0), 0);
2895 else if (TREE_CODE (target) == INDIRECT_REF
2896 && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR
2897 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0))
2898 == ADDR_EXPR)
2899 target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0);
2900 else
2901 break;
2904 switch (TREE_CODE (target))
2906 case VAR_DECL:
2907 case FUNCTION_DECL:
2908 x = DECL_RTL (target);
2909 break;
2911 case LABEL_DECL:
2912 x = gen_rtx_MEM (FUNCTION_MODE,
2913 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2914 break;
2916 case REAL_CST:
2917 case FIXED_CST:
2918 case STRING_CST:
2919 case COMPLEX_CST:
2920 case CONSTRUCTOR:
2921 case INTEGER_CST:
2922 x = output_constant_def (target, 1);
2923 break;
2925 default:
2926 gcc_unreachable ();
2929 gcc_assert (MEM_P (x));
2930 x = XEXP (x, 0);
2932 value->base = x;
2933 value->offset = offset;
2936 static GTY(()) hash_table<tree_descriptor_hasher> *const_desc_htab;
2938 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2940 /* Constant pool accessor function. */
2942 hash_table<tree_descriptor_hasher> *
2943 constant_pool_htab (void)
2945 return const_desc_htab;
2948 /* Compute a hash code for a constant expression. */
2950 hashval_t
2951 tree_descriptor_hasher::hash (constant_descriptor_tree *ptr)
2953 return ptr->hash;
2956 static hashval_t
2957 const_hash_1 (const tree exp)
2959 const char *p;
2960 hashval_t hi;
2961 int len, i;
2962 enum tree_code code = TREE_CODE (exp);
2964 /* Either set P and LEN to the address and len of something to hash and
2965 exit the switch or return a value. */
2967 switch (code)
2969 case INTEGER_CST:
2970 p = (char *) &TREE_INT_CST_ELT (exp, 0);
2971 len = TREE_INT_CST_NUNITS (exp) * sizeof (HOST_WIDE_INT);
2972 break;
2974 case REAL_CST:
2975 return real_hash (TREE_REAL_CST_PTR (exp));
2977 case FIXED_CST:
2978 return fixed_hash (TREE_FIXED_CST_PTR (exp));
2980 case STRING_CST:
2981 p = TREE_STRING_POINTER (exp);
2982 len = TREE_STRING_LENGTH (exp);
2983 break;
2985 case COMPLEX_CST:
2986 return (const_hash_1 (TREE_REALPART (exp)) * 5
2987 + const_hash_1 (TREE_IMAGPART (exp)));
2989 case VECTOR_CST:
2991 unsigned i;
2993 hi = 7 + VECTOR_CST_NELTS (exp);
2995 for (i = 0; i < VECTOR_CST_NELTS (exp); ++i)
2996 hi = hi * 563 + const_hash_1 (VECTOR_CST_ELT (exp, i));
2998 return hi;
3001 case CONSTRUCTOR:
3003 unsigned HOST_WIDE_INT idx;
3004 tree value;
3006 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
3008 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
3009 if (value)
3010 hi = hi * 603 + const_hash_1 (value);
3012 return hi;
3015 case ADDR_EXPR:
3016 case FDESC_EXPR:
3018 struct addr_const value;
3020 decode_addr_const (exp, &value);
3021 switch (GET_CODE (value.base))
3023 case SYMBOL_REF:
3024 /* Don't hash the address of the SYMBOL_REF;
3025 only use the offset and the symbol name. */
3026 hi = value.offset;
3027 p = XSTR (value.base, 0);
3028 for (i = 0; p[i] != 0; i++)
3029 hi = ((hi * 613) + (unsigned) (p[i]));
3030 break;
3032 case LABEL_REF:
3033 hi = (value.offset
3034 + CODE_LABEL_NUMBER (label_ref_label (value.base)) * 13);
3035 break;
3037 default:
3038 gcc_unreachable ();
3041 return hi;
3043 case PLUS_EXPR:
3044 case POINTER_PLUS_EXPR:
3045 case MINUS_EXPR:
3046 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
3047 + const_hash_1 (TREE_OPERAND (exp, 1)));
3049 CASE_CONVERT:
3050 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
3052 default:
3053 /* A language specific constant. Just hash the code. */
3054 return code;
3057 /* Compute hashing function. */
3058 hi = len;
3059 for (i = 0; i < len; i++)
3060 hi = ((hi * 613) + (unsigned) (p[i]));
3062 return hi;
3065 /* Wrapper of compare_constant, for the htab interface. */
3066 bool
3067 tree_descriptor_hasher::equal (constant_descriptor_tree *c1,
3068 constant_descriptor_tree *c2)
3070 if (c1->hash != c2->hash)
3071 return 0;
3072 return compare_constant (c1->value, c2->value);
3075 /* Compare t1 and t2, and return 1 only if they are known to result in
3076 the same bit pattern on output. */
3078 static int
3079 compare_constant (const tree t1, const tree t2)
3081 enum tree_code typecode;
3083 if (t1 == NULL_TREE)
3084 return t2 == NULL_TREE;
3085 if (t2 == NULL_TREE)
3086 return 0;
3088 if (TREE_CODE (t1) != TREE_CODE (t2))
3089 return 0;
3091 switch (TREE_CODE (t1))
3093 case INTEGER_CST:
3094 /* Integer constants are the same only if the same width of type. */
3095 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3096 return 0;
3097 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3098 return 0;
3099 return tree_int_cst_equal (t1, t2);
3101 case REAL_CST:
3102 /* Real constants are the same only if the same width of type. */
3103 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3104 return 0;
3106 return real_identical (&TREE_REAL_CST (t1), &TREE_REAL_CST (t2));
3108 case FIXED_CST:
3109 /* Fixed constants are the same only if the same width of type. */
3110 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3111 return 0;
3113 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
3115 case STRING_CST:
3116 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3117 return 0;
3119 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
3120 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
3121 TREE_STRING_LENGTH (t1)));
3123 case COMPLEX_CST:
3124 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
3125 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
3127 case VECTOR_CST:
3129 unsigned i;
3131 if (VECTOR_CST_NELTS (t1) != VECTOR_CST_NELTS (t2))
3132 return 0;
3134 for (i = 0; i < VECTOR_CST_NELTS (t1); ++i)
3135 if (!compare_constant (VECTOR_CST_ELT (t1, i),
3136 VECTOR_CST_ELT (t2, i)))
3137 return 0;
3139 return 1;
3142 case CONSTRUCTOR:
3144 vec<constructor_elt, va_gc> *v1, *v2;
3145 unsigned HOST_WIDE_INT idx;
3147 typecode = TREE_CODE (TREE_TYPE (t1));
3148 if (typecode != TREE_CODE (TREE_TYPE (t2)))
3149 return 0;
3151 if (typecode == ARRAY_TYPE)
3153 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
3154 /* For arrays, check that mode, size and storage order match. */
3155 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
3156 || size_1 == -1
3157 || size_1 != int_size_in_bytes (TREE_TYPE (t2))
3158 || TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (t1))
3159 != TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (t2)))
3160 return 0;
3162 else
3164 /* For record and union constructors, require exact type
3165 equality. */
3166 if (TREE_TYPE (t1) != TREE_TYPE (t2))
3167 return 0;
3170 v1 = CONSTRUCTOR_ELTS (t1);
3171 v2 = CONSTRUCTOR_ELTS (t2);
3172 if (vec_safe_length (v1) != vec_safe_length (v2))
3173 return 0;
3175 for (idx = 0; idx < vec_safe_length (v1); ++idx)
3177 constructor_elt *c1 = &(*v1)[idx];
3178 constructor_elt *c2 = &(*v2)[idx];
3180 /* Check that each value is the same... */
3181 if (!compare_constant (c1->value, c2->value))
3182 return 0;
3183 /* ... and that they apply to the same fields! */
3184 if (typecode == ARRAY_TYPE)
3186 if (!compare_constant (c1->index, c2->index))
3187 return 0;
3189 else
3191 if (c1->index != c2->index)
3192 return 0;
3196 return 1;
3199 case ADDR_EXPR:
3200 case FDESC_EXPR:
3202 struct addr_const value1, value2;
3203 enum rtx_code code;
3204 int ret;
3206 decode_addr_const (t1, &value1);
3207 decode_addr_const (t2, &value2);
3209 if (value1.offset != value2.offset)
3210 return 0;
3212 code = GET_CODE (value1.base);
3213 if (code != GET_CODE (value2.base))
3214 return 0;
3216 switch (code)
3218 case SYMBOL_REF:
3219 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3220 break;
3222 case LABEL_REF:
3223 ret = (CODE_LABEL_NUMBER (label_ref_label (value1.base))
3224 == CODE_LABEL_NUMBER (label_ref_label (value2.base)));
3225 break;
3227 default:
3228 gcc_unreachable ();
3230 return ret;
3233 case PLUS_EXPR:
3234 case POINTER_PLUS_EXPR:
3235 case MINUS_EXPR:
3236 case RANGE_EXPR:
3237 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3238 && compare_constant (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3240 CASE_CONVERT:
3241 case VIEW_CONVERT_EXPR:
3242 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3244 default:
3245 return 0;
3248 gcc_unreachable ();
3251 /* Return the section into which constant EXP should be placed. */
3253 static section *
3254 get_constant_section (tree exp, unsigned int align)
3256 return targetm.asm_out.select_section (exp,
3257 compute_reloc_for_constant (exp),
3258 align);
3261 /* Return the size of constant EXP in bytes. */
3263 static HOST_WIDE_INT
3264 get_constant_size (tree exp)
3266 HOST_WIDE_INT size;
3268 size = int_size_in_bytes (TREE_TYPE (exp));
3269 if (TREE_CODE (exp) == STRING_CST)
3270 size = MAX (TREE_STRING_LENGTH (exp), size);
3271 return size;
3274 /* Subroutine of output_constant_def:
3275 No constant equal to EXP is known to have been output.
3276 Make a constant descriptor to enter EXP in the hash table.
3277 Assign the label number and construct RTL to refer to the
3278 constant's location in memory.
3279 Caller is responsible for updating the hash table. */
3281 static struct constant_descriptor_tree *
3282 build_constant_desc (tree exp)
3284 struct constant_descriptor_tree *desc;
3285 rtx symbol, rtl;
3286 char label[256];
3287 int labelno;
3288 tree decl;
3290 desc = ggc_alloc<constant_descriptor_tree> ();
3291 desc->value = exp;
3293 /* Create a string containing the label name, in LABEL. */
3294 labelno = const_labelno++;
3295 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3297 /* Construct the VAR_DECL associated with the constant. */
3298 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3299 TREE_TYPE (exp));
3300 DECL_ARTIFICIAL (decl) = 1;
3301 DECL_IGNORED_P (decl) = 1;
3302 TREE_READONLY (decl) = 1;
3303 TREE_STATIC (decl) = 1;
3304 TREE_ADDRESSABLE (decl) = 1;
3305 /* We don't set the RTL yet as this would cause varpool to assume that the
3306 variable is referenced. Moreover, it would just be dropped in LTO mode.
3307 Instead we set the flag that will be recognized in make_decl_rtl. */
3308 DECL_IN_CONSTANT_POOL (decl) = 1;
3309 DECL_INITIAL (decl) = desc->value;
3310 /* ??? CONSTANT_ALIGNMENT hasn't been updated for vector types on most
3311 architectures so use DATA_ALIGNMENT as well, except for strings. */
3312 if (TREE_CODE (exp) == STRING_CST)
3314 SET_DECL_ALIGN (decl, CONSTANT_ALIGNMENT (exp, DECL_ALIGN (decl)));
3316 else
3317 align_variable (decl, 0);
3319 /* Now construct the SYMBOL_REF and the MEM. */
3320 if (use_object_blocks_p ())
3322 int align = (TREE_CODE (decl) == CONST_DECL
3323 || (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
3324 ? DECL_ALIGN (decl)
3325 : symtab_node::get (decl)->definition_alignment ());
3326 section *sect = get_constant_section (exp, align);
3327 symbol = create_block_symbol (ggc_strdup (label),
3328 get_block_for_section (sect), -1);
3330 else
3331 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3332 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3333 SET_SYMBOL_REF_DECL (symbol, decl);
3334 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3336 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3337 set_mem_attributes (rtl, exp, 1);
3338 set_mem_alias_set (rtl, 0);
3340 /* Putting EXP into the literal pool might have imposed a different
3341 alignment which should be visible in the RTX as well. */
3342 set_mem_align (rtl, DECL_ALIGN (decl));
3344 /* We cannot share RTX'es in pool entries.
3345 Mark this piece of RTL as required for unsharing. */
3346 RTX_FLAG (rtl, used) = 1;
3348 /* Set flags or add text to the name to record information, such as
3349 that it is a local symbol. If the name is changed, the macro
3350 ASM_OUTPUT_LABELREF will have to know how to strip this
3351 information. This call might invalidate our local variable
3352 SYMBOL; we can't use it afterward. */
3353 targetm.encode_section_info (exp, rtl, true);
3355 desc->rtl = rtl;
3357 return desc;
3360 /* Return an rtx representing a reference to constant data in memory
3361 for the constant expression EXP.
3363 If assembler code for such a constant has already been output,
3364 return an rtx to refer to it.
3365 Otherwise, output such a constant in memory
3366 and generate an rtx for it.
3368 If DEFER is nonzero, this constant can be deferred and output only
3369 if referenced in the function after all optimizations.
3371 `const_desc_table' records which constants already have label strings. */
3374 output_constant_def (tree exp, int defer)
3376 struct constant_descriptor_tree *desc;
3377 struct constant_descriptor_tree key;
3379 /* Look up EXP in the table of constant descriptors. If we didn't find
3380 it, create a new one. */
3381 key.value = exp;
3382 key.hash = const_hash_1 (exp);
3383 constant_descriptor_tree **loc
3384 = const_desc_htab->find_slot_with_hash (&key, key.hash, INSERT);
3386 desc = *loc;
3387 if (desc == 0)
3389 desc = build_constant_desc (exp);
3390 desc->hash = key.hash;
3391 *loc = desc;
3394 maybe_output_constant_def_contents (desc, defer);
3395 return desc->rtl;
3398 /* Subroutine of output_constant_def: Decide whether or not we need to
3399 output the constant DESC now, and if so, do it. */
3400 static void
3401 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3402 int defer)
3404 rtx symbol = XEXP (desc->rtl, 0);
3405 tree exp = desc->value;
3407 if (flag_syntax_only)
3408 return;
3410 if (TREE_ASM_WRITTEN (exp))
3411 /* Already output; don't do it again. */
3412 return;
3414 /* We can always defer constants as long as the context allows
3415 doing so. */
3416 if (defer)
3418 /* Increment n_deferred_constants if it exists. It needs to be at
3419 least as large as the number of constants actually referred to
3420 by the function. If it's too small we'll stop looking too early
3421 and fail to emit constants; if it's too large we'll only look
3422 through the entire function when we could have stopped earlier. */
3423 if (cfun)
3424 n_deferred_constants++;
3425 return;
3428 output_constant_def_contents (symbol);
3431 /* Subroutine of output_constant_def_contents. Output the definition
3432 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3433 constant's alignment in bits. */
3435 static void
3436 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3438 HOST_WIDE_INT size;
3440 size = get_constant_size (exp);
3442 /* Do any machine/system dependent processing of the constant. */
3443 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3445 /* Output the value of EXP. */
3446 output_constant (exp, size, align, false);
3448 targetm.asm_out.decl_end ();
3451 /* We must output the constant data referred to by SYMBOL; do so. */
3453 static void
3454 output_constant_def_contents (rtx symbol)
3456 tree decl = SYMBOL_REF_DECL (symbol);
3457 tree exp = DECL_INITIAL (decl);
3458 bool asan_protected = false;
3460 /* Make sure any other constants whose addresses appear in EXP
3461 are assigned label numbers. */
3462 output_addressed_constants (exp);
3464 /* We are no longer deferring this constant. */
3465 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3467 if ((flag_sanitize & SANITIZE_ADDRESS)
3468 && TREE_CODE (exp) == STRING_CST
3469 && asan_protect_global (exp))
3471 asan_protected = true;
3472 SET_DECL_ALIGN (decl, MAX (DECL_ALIGN (decl),
3473 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT));
3476 /* If the constant is part of an object block, make sure that the
3477 decl has been positioned within its block, but do not write out
3478 its definition yet. output_object_blocks will do that later. */
3479 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3480 place_block_symbol (symbol);
3481 else
3483 int align = (TREE_CODE (decl) == CONST_DECL
3484 || (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
3485 ? DECL_ALIGN (decl)
3486 : symtab_node::get (decl)->definition_alignment ());
3487 switch_to_section (get_constant_section (exp, align));
3488 if (align > BITS_PER_UNIT)
3489 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3490 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3491 if (asan_protected)
3493 HOST_WIDE_INT size = get_constant_size (exp);
3494 assemble_zeros (asan_red_zone_size (size));
3499 /* Look up EXP in the table of constant descriptors. Return the rtl
3500 if it has been emitted, else null. */
3503 lookup_constant_def (tree exp)
3505 struct constant_descriptor_tree key;
3507 key.value = exp;
3508 key.hash = const_hash_1 (exp);
3509 constant_descriptor_tree *desc
3510 = const_desc_htab->find_with_hash (&key, key.hash);
3512 return (desc ? desc->rtl : NULL_RTX);
3515 /* Return a tree representing a reference to constant data in memory
3516 for the constant expression EXP.
3518 This is the counterpart of output_constant_def at the Tree level. */
3520 tree
3521 tree_output_constant_def (tree exp)
3523 struct constant_descriptor_tree *desc, key;
3524 tree decl;
3526 /* Look up EXP in the table of constant descriptors. If we didn't find
3527 it, create a new one. */
3528 key.value = exp;
3529 key.hash = const_hash_1 (exp);
3530 constant_descriptor_tree **loc
3531 = const_desc_htab->find_slot_with_hash (&key, key.hash, INSERT);
3533 desc = *loc;
3534 if (desc == 0)
3536 desc = build_constant_desc (exp);
3537 desc->hash = key.hash;
3538 *loc = desc;
3541 decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3542 varpool_node::finalize_decl (decl);
3543 return decl;
3546 struct GTY((chain_next ("%h.next"), for_user)) constant_descriptor_rtx {
3547 struct constant_descriptor_rtx *next;
3548 rtx mem;
3549 rtx sym;
3550 rtx constant;
3551 HOST_WIDE_INT offset;
3552 hashval_t hash;
3553 machine_mode mode;
3554 unsigned int align;
3555 int labelno;
3556 int mark;
3559 struct const_rtx_desc_hasher : ggc_ptr_hash<constant_descriptor_rtx>
3561 static hashval_t hash (constant_descriptor_rtx *);
3562 static bool equal (constant_descriptor_rtx *, constant_descriptor_rtx *);
3565 /* Used in the hash tables to avoid outputting the same constant
3566 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3567 are output once per function, not once per file. */
3568 /* ??? Only a few targets need per-function constant pools. Most
3569 can use one per-file pool. Should add a targetm bit to tell the
3570 difference. */
3572 struct GTY(()) rtx_constant_pool {
3573 /* Pointers to first and last constant in pool, as ordered by offset. */
3574 struct constant_descriptor_rtx *first;
3575 struct constant_descriptor_rtx *last;
3577 /* Hash facility for making memory-constants from constant rtl-expressions.
3578 It is used on RISC machines where immediate integer arguments and
3579 constant addresses are restricted so that such constants must be stored
3580 in memory. */
3581 hash_table<const_rtx_desc_hasher> *const_rtx_htab;
3583 /* Current offset in constant pool (does not include any
3584 machine-specific header). */
3585 HOST_WIDE_INT offset;
3588 /* Hash and compare functions for const_rtx_htab. */
3590 hashval_t
3591 const_rtx_desc_hasher::hash (constant_descriptor_rtx *desc)
3593 return desc->hash;
3596 bool
3597 const_rtx_desc_hasher::equal (constant_descriptor_rtx *x,
3598 constant_descriptor_rtx *y)
3600 if (x->mode != y->mode)
3601 return 0;
3602 return rtx_equal_p (x->constant, y->constant);
3605 /* Hash one component of a constant. */
3607 static hashval_t
3608 const_rtx_hash_1 (const_rtx x)
3610 unsigned HOST_WIDE_INT hwi;
3611 machine_mode mode;
3612 enum rtx_code code;
3613 hashval_t h;
3614 int i;
3616 code = GET_CODE (x);
3617 mode = GET_MODE (x);
3618 h = (hashval_t) code * 1048573 + mode;
3620 switch (code)
3622 case CONST_INT:
3623 hwi = INTVAL (x);
3625 fold_hwi:
3627 int shift = sizeof (hashval_t) * CHAR_BIT;
3628 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3630 h ^= (hashval_t) hwi;
3631 for (i = 1; i < n; ++i)
3633 hwi >>= shift;
3634 h ^= (hashval_t) hwi;
3637 break;
3639 case CONST_WIDE_INT:
3640 hwi = GET_MODE_PRECISION (mode);
3642 for (i = 0; i < CONST_WIDE_INT_NUNITS (x); i++)
3643 hwi ^= CONST_WIDE_INT_ELT (x, i);
3644 goto fold_hwi;
3647 case CONST_DOUBLE:
3648 if (TARGET_SUPPORTS_WIDE_INT == 0 && mode == VOIDmode)
3650 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3651 goto fold_hwi;
3653 else
3654 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3655 break;
3657 case CONST_FIXED:
3658 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3659 break;
3661 case SYMBOL_REF:
3662 h ^= htab_hash_string (XSTR (x, 0));
3663 break;
3665 case LABEL_REF:
3666 h = h * 251 + CODE_LABEL_NUMBER (label_ref_label (x));
3667 break;
3669 case UNSPEC:
3670 case UNSPEC_VOLATILE:
3671 h = h * 251 + XINT (x, 1);
3672 break;
3674 default:
3675 break;
3678 return h;
3681 /* Compute a hash value for X, which should be a constant. */
3683 static hashval_t
3684 const_rtx_hash (rtx x)
3686 hashval_t h = 0;
3687 subrtx_iterator::array_type array;
3688 FOR_EACH_SUBRTX (iter, array, x, ALL)
3689 h = h * 509 + const_rtx_hash_1 (*iter);
3690 return h;
3694 /* Create and return a new rtx constant pool. */
3696 static struct rtx_constant_pool *
3697 create_constant_pool (void)
3699 struct rtx_constant_pool *pool;
3701 pool = ggc_alloc<rtx_constant_pool> ();
3702 pool->const_rtx_htab = hash_table<const_rtx_desc_hasher>::create_ggc (31);
3703 pool->first = NULL;
3704 pool->last = NULL;
3705 pool->offset = 0;
3706 return pool;
3709 /* Initialize constant pool hashing for a new function. */
3711 void
3712 init_varasm_status (void)
3714 crtl->varasm.pool = create_constant_pool ();
3715 crtl->varasm.deferred_constants = 0;
3718 /* Given a MINUS expression, simplify it if both sides
3719 include the same symbol. */
3722 simplify_subtraction (rtx x)
3724 rtx r = simplify_rtx (x);
3725 return r ? r : x;
3728 /* Given a constant rtx X, make (or find) a memory constant for its value
3729 and return a MEM rtx to refer to it in memory. */
3732 force_const_mem (machine_mode mode, rtx x)
3734 struct constant_descriptor_rtx *desc, tmp;
3735 struct rtx_constant_pool *pool;
3736 char label[256];
3737 rtx def, symbol;
3738 hashval_t hash;
3739 unsigned int align;
3740 constant_descriptor_rtx **slot;
3742 /* If we're not allowed to drop X into the constant pool, don't. */
3743 if (targetm.cannot_force_const_mem (mode, x))
3744 return NULL_RTX;
3746 /* Record that this function has used a constant pool entry. */
3747 crtl->uses_const_pool = 1;
3749 /* Decide which pool to use. */
3750 pool = (targetm.use_blocks_for_constant_p (mode, x)
3751 ? shared_constant_pool
3752 : crtl->varasm.pool);
3754 /* Lookup the value in the hashtable. */
3755 tmp.constant = x;
3756 tmp.mode = mode;
3757 hash = const_rtx_hash (x);
3758 slot = pool->const_rtx_htab->find_slot_with_hash (&tmp, hash, INSERT);
3759 desc = *slot;
3761 /* If the constant was already present, return its memory. */
3762 if (desc)
3763 return copy_rtx (desc->mem);
3765 /* Otherwise, create a new descriptor. */
3766 desc = ggc_alloc<constant_descriptor_rtx> ();
3767 *slot = desc;
3769 /* Align the location counter as required by EXP's data type. */
3770 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3772 tree type = lang_hooks.types.type_for_mode (mode, 0);
3773 if (type != NULL_TREE)
3774 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3776 pool->offset += (align / BITS_PER_UNIT) - 1;
3777 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3779 desc->next = NULL;
3780 desc->constant = copy_rtx (tmp.constant);
3781 desc->offset = pool->offset;
3782 desc->hash = hash;
3783 desc->mode = mode;
3784 desc->align = align;
3785 desc->labelno = const_labelno;
3786 desc->mark = 0;
3788 pool->offset += GET_MODE_SIZE (mode);
3789 if (pool->last)
3790 pool->last->next = desc;
3791 else
3792 pool->first = pool->last = desc;
3793 pool->last = desc;
3795 /* Create a string containing the label name, in LABEL. */
3796 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3797 ++const_labelno;
3799 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3800 the constants pool. */
3801 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3803 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3804 symbol = create_block_symbol (ggc_strdup (label),
3805 get_block_for_section (sect), -1);
3807 else
3808 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3809 desc->sym = symbol;
3810 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3811 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3812 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3814 /* Construct the MEM. */
3815 desc->mem = def = gen_const_mem (mode, symbol);
3816 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3817 set_mem_align (def, align);
3819 /* If we're dropping a label to the constant pool, make sure we
3820 don't delete it. */
3821 if (GET_CODE (x) == LABEL_REF)
3822 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3824 return copy_rtx (def);
3827 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3830 get_pool_constant (const_rtx addr)
3832 return SYMBOL_REF_CONSTANT (addr)->constant;
3835 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3836 and whether it has been output or not. */
3839 get_pool_constant_mark (rtx addr, bool *pmarked)
3841 struct constant_descriptor_rtx *desc;
3843 desc = SYMBOL_REF_CONSTANT (addr);
3844 *pmarked = (desc->mark != 0);
3845 return desc->constant;
3848 /* Similar, return the mode. */
3850 machine_mode
3851 get_pool_mode (const_rtx addr)
3853 return SYMBOL_REF_CONSTANT (addr)->mode;
3856 /* Return TRUE if and only if the constant pool has no entries. Note
3857 that even entries we might end up choosing not to emit are counted
3858 here, so there is the potential for missed optimizations. */
3860 bool
3861 constant_pool_empty_p (void)
3863 return crtl->varasm.pool->first == NULL;
3866 /* Worker function for output_constant_pool_1. Emit assembly for X
3867 in MODE with known alignment ALIGN. */
3869 static void
3870 output_constant_pool_2 (machine_mode mode, rtx x, unsigned int align)
3872 switch (GET_MODE_CLASS (mode))
3874 case MODE_FLOAT:
3875 case MODE_DECIMAL_FLOAT:
3877 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3878 assemble_real (*CONST_DOUBLE_REAL_VALUE (x), mode, align, false);
3879 break;
3882 case MODE_INT:
3883 case MODE_PARTIAL_INT:
3884 case MODE_FRACT:
3885 case MODE_UFRACT:
3886 case MODE_ACCUM:
3887 case MODE_UACCUM:
3888 case MODE_POINTER_BOUNDS:
3889 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3890 break;
3892 case MODE_VECTOR_FLOAT:
3893 case MODE_VECTOR_INT:
3894 case MODE_VECTOR_FRACT:
3895 case MODE_VECTOR_UFRACT:
3896 case MODE_VECTOR_ACCUM:
3897 case MODE_VECTOR_UACCUM:
3899 int i, units;
3900 machine_mode submode = GET_MODE_INNER (mode);
3901 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3903 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3904 units = CONST_VECTOR_NUNITS (x);
3906 for (i = 0; i < units; i++)
3908 rtx elt = CONST_VECTOR_ELT (x, i);
3909 output_constant_pool_2 (submode, elt, i ? subalign : align);
3912 break;
3914 default:
3915 gcc_unreachable ();
3919 /* Worker function for output_constant_pool. Emit constant DESC,
3920 giving it ALIGN bits of alignment. */
3922 static void
3923 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3924 unsigned int align)
3926 rtx x, tmp;
3928 x = desc->constant;
3930 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3931 whose CODE_LABEL has been deleted. This can occur if a jump table
3932 is eliminated by optimization. If so, write a constant of zero
3933 instead. Note that this can also happen by turning the
3934 CODE_LABEL into a NOTE. */
3935 /* ??? This seems completely and utterly wrong. Certainly it's
3936 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3937 functioning even with rtx_insn::deleted and friends. */
3939 tmp = x;
3940 switch (GET_CODE (tmp))
3942 case CONST:
3943 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3944 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
3945 break;
3946 tmp = XEXP (XEXP (tmp, 0), 0);
3947 /* FALLTHRU */
3949 case LABEL_REF:
3951 rtx_insn *insn = label_ref_label (tmp);
3952 gcc_assert (!insn->deleted ());
3953 gcc_assert (!NOTE_P (insn)
3954 || NOTE_KIND (insn) != NOTE_INSN_DELETED);
3955 break;
3958 default:
3959 break;
3962 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3963 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3964 align, desc->labelno, done);
3965 #endif
3967 assemble_align (align);
3969 /* Output the label. */
3970 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3972 /* Output the data.
3973 Pass actual alignment value while emitting string constant to asm code
3974 as function 'output_constant_pool_1' explicitly passes the alignment as 1
3975 assuming that the data is already aligned which prevents the generation
3976 of fix-up table entries. */
3977 output_constant_pool_2 (desc->mode, x, desc->align);
3979 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3980 sections have proper size. */
3981 if (align > GET_MODE_BITSIZE (desc->mode)
3982 && in_section
3983 && (in_section->common.flags & SECTION_MERGE))
3984 assemble_align (align);
3986 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3987 done:
3988 #endif
3989 return;
3992 /* Recompute the offsets of entries in POOL, and the overall size of
3993 POOL. Do this after calling mark_constant_pool to ensure that we
3994 are computing the offset values for the pool which we will actually
3995 emit. */
3997 static void
3998 recompute_pool_offsets (struct rtx_constant_pool *pool)
4000 struct constant_descriptor_rtx *desc;
4001 pool->offset = 0;
4003 for (desc = pool->first; desc ; desc = desc->next)
4004 if (desc->mark)
4006 /* Recalculate offset. */
4007 unsigned int align = desc->align;
4008 pool->offset += (align / BITS_PER_UNIT) - 1;
4009 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
4010 desc->offset = pool->offset;
4011 pool->offset += GET_MODE_SIZE (desc->mode);
4015 /* Mark all constants that are referenced by SYMBOL_REFs in X.
4016 Emit referenced deferred strings. */
4018 static void
4019 mark_constants_in_pattern (rtx insn)
4021 subrtx_iterator::array_type array;
4022 FOR_EACH_SUBRTX (iter, array, PATTERN (insn), ALL)
4024 const_rtx x = *iter;
4025 if (GET_CODE (x) == SYMBOL_REF)
4027 if (CONSTANT_POOL_ADDRESS_P (x))
4029 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
4030 if (desc->mark == 0)
4032 desc->mark = 1;
4033 iter.substitute (desc->constant);
4036 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
4038 tree decl = SYMBOL_REF_DECL (x);
4039 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
4041 n_deferred_constants--;
4042 output_constant_def_contents (CONST_CAST_RTX (x));
4049 /* Look through appropriate parts of INSN, marking all entries in the
4050 constant pool which are actually being used. Entries that are only
4051 referenced by other constants are also marked as used. Emit
4052 deferred strings that are used. */
4054 static void
4055 mark_constants (rtx_insn *insn)
4057 if (!INSN_P (insn))
4058 return;
4060 /* Insns may appear inside a SEQUENCE. Only check the patterns of
4061 insns, not any notes that may be attached. We don't want to mark
4062 a constant just because it happens to appear in a REG_EQUIV note. */
4063 if (rtx_sequence *seq = dyn_cast <rtx_sequence *> (PATTERN (insn)))
4065 int i, n = seq->len ();
4066 for (i = 0; i < n; ++i)
4068 rtx subinsn = seq->element (i);
4069 if (INSN_P (subinsn))
4070 mark_constants_in_pattern (subinsn);
4073 else
4074 mark_constants_in_pattern (insn);
4077 /* Look through the instructions for this function, and mark all the
4078 entries in POOL which are actually being used. Emit deferred constants
4079 which have indeed been used. */
4081 static void
4082 mark_constant_pool (void)
4084 rtx_insn *insn;
4086 if (!crtl->uses_const_pool && n_deferred_constants == 0)
4087 return;
4089 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4090 mark_constants (insn);
4093 /* Write all the constants in POOL. */
4095 static void
4096 output_constant_pool_contents (struct rtx_constant_pool *pool)
4098 struct constant_descriptor_rtx *desc;
4100 for (desc = pool->first; desc ; desc = desc->next)
4101 if (desc->mark)
4103 /* If the constant is part of an object_block, make sure that
4104 the constant has been positioned within its block, but do not
4105 write out its definition yet. output_object_blocks will do
4106 that later. */
4107 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
4108 && SYMBOL_REF_BLOCK (desc->sym))
4109 place_block_symbol (desc->sym);
4110 else
4112 switch_to_section (targetm.asm_out.select_rtx_section
4113 (desc->mode, desc->constant, desc->align));
4114 output_constant_pool_1 (desc, desc->align);
4119 /* Mark all constants that are used in the current function, then write
4120 out the function's private constant pool. */
4122 static void
4123 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
4124 tree fndecl ATTRIBUTE_UNUSED)
4126 struct rtx_constant_pool *pool = crtl->varasm.pool;
4128 /* It is possible for gcc to call force_const_mem and then to later
4129 discard the instructions which refer to the constant. In such a
4130 case we do not need to output the constant. */
4131 mark_constant_pool ();
4133 /* Having marked the constant pool entries we'll actually emit, we
4134 now need to rebuild the offset information, which may have become
4135 stale. */
4136 recompute_pool_offsets (pool);
4138 #ifdef ASM_OUTPUT_POOL_PROLOGUE
4139 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
4140 #endif
4142 output_constant_pool_contents (pool);
4144 #ifdef ASM_OUTPUT_POOL_EPILOGUE
4145 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
4146 #endif
4149 /* Write the contents of the shared constant pool. */
4151 void
4152 output_shared_constant_pool (void)
4154 output_constant_pool_contents (shared_constant_pool);
4157 /* Determine what kind of relocations EXP may need. */
4160 compute_reloc_for_constant (tree exp)
4162 int reloc = 0, reloc2;
4163 tree tem;
4165 switch (TREE_CODE (exp))
4167 case ADDR_EXPR:
4168 case FDESC_EXPR:
4169 /* Go inside any operations that get_inner_reference can handle and see
4170 if what's inside is a constant: no need to do anything here for
4171 addresses of variables or functions. */
4172 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4173 tem = TREE_OPERAND (tem, 0))
4176 if (TREE_CODE (tem) == MEM_REF
4177 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4179 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4180 break;
4183 if (!targetm.binds_local_p (tem))
4184 reloc |= 2;
4185 else
4186 reloc |= 1;
4187 break;
4189 case PLUS_EXPR:
4190 case POINTER_PLUS_EXPR:
4191 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4192 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4193 break;
4195 case MINUS_EXPR:
4196 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4197 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4198 /* The difference of two local labels is computable at link time. */
4199 if (reloc == 1 && reloc2 == 1)
4200 reloc = 0;
4201 else
4202 reloc |= reloc2;
4203 break;
4205 CASE_CONVERT:
4206 case VIEW_CONVERT_EXPR:
4207 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4208 break;
4210 case CONSTRUCTOR:
4212 unsigned HOST_WIDE_INT idx;
4213 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4214 if (tem != 0)
4215 reloc |= compute_reloc_for_constant (tem);
4217 break;
4219 default:
4220 break;
4222 return reloc;
4225 /* Find all the constants whose addresses are referenced inside of EXP,
4226 and make sure assembler code with a label has been output for each one.
4227 Indicate whether an ADDR_EXPR has been encountered. */
4229 static void
4230 output_addressed_constants (tree exp)
4232 tree tem;
4234 switch (TREE_CODE (exp))
4236 case ADDR_EXPR:
4237 case FDESC_EXPR:
4238 /* Go inside any operations that get_inner_reference can handle and see
4239 if what's inside is a constant: no need to do anything here for
4240 addresses of variables or functions. */
4241 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4242 tem = TREE_OPERAND (tem, 0))
4245 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4246 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4247 tem = DECL_INITIAL (tem);
4249 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4250 output_constant_def (tem, 0);
4252 if (TREE_CODE (tem) == MEM_REF)
4253 output_addressed_constants (TREE_OPERAND (tem, 0));
4254 break;
4256 case PLUS_EXPR:
4257 case POINTER_PLUS_EXPR:
4258 case MINUS_EXPR:
4259 output_addressed_constants (TREE_OPERAND (exp, 1));
4260 gcc_fallthrough ();
4262 CASE_CONVERT:
4263 case VIEW_CONVERT_EXPR:
4264 output_addressed_constants (TREE_OPERAND (exp, 0));
4265 break;
4267 case CONSTRUCTOR:
4269 unsigned HOST_WIDE_INT idx;
4270 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4271 if (tem != 0)
4272 output_addressed_constants (tem);
4274 break;
4276 default:
4277 break;
4281 /* Whether a constructor CTOR is a valid static constant initializer if all
4282 its elements are. This used to be internal to initializer_constant_valid_p
4283 and has been exposed to let other functions like categorize_ctor_elements
4284 evaluate the property while walking a constructor for other purposes. */
4286 bool
4287 constructor_static_from_elts_p (const_tree ctor)
4289 return (TREE_CONSTANT (ctor)
4290 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4291 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4292 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4295 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4296 tree *cache);
4298 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4299 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4300 which are valid when ENDTYPE is an integer of any size; in
4301 particular, this does not accept a pointer minus a constant. This
4302 returns null_pointer_node if the VALUE is an absolute constant
4303 which can be used to initialize a static variable. Otherwise it
4304 returns NULL. */
4306 static tree
4307 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4309 tree op0, op1;
4311 if (!INTEGRAL_TYPE_P (endtype))
4312 return NULL_TREE;
4314 op0 = TREE_OPERAND (value, 0);
4315 op1 = TREE_OPERAND (value, 1);
4317 /* Like STRIP_NOPS except allow the operand mode to widen. This
4318 works around a feature of fold that simplifies (int)(p1 - p2) to
4319 ((int)p1 - (int)p2) under the theory that the narrower operation
4320 is cheaper. */
4322 while (CONVERT_EXPR_P (op0)
4323 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4325 tree inner = TREE_OPERAND (op0, 0);
4326 if (inner == error_mark_node
4327 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4328 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
4329 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4330 break;
4331 op0 = inner;
4334 while (CONVERT_EXPR_P (op1)
4335 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4337 tree inner = TREE_OPERAND (op1, 0);
4338 if (inner == error_mark_node
4339 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4340 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
4341 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4342 break;
4343 op1 = inner;
4346 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4347 if (!op0)
4348 return NULL_TREE;
4350 op1 = initializer_constant_valid_p_1 (op1, endtype,
4351 cache ? cache + 2 : NULL);
4352 /* Both initializers must be known. */
4353 if (op1)
4355 if (op0 == op1
4356 && (op0 == null_pointer_node
4357 || TREE_CODE (value) == MINUS_EXPR))
4358 return null_pointer_node;
4360 /* Support differences between labels. */
4361 if (TREE_CODE (op0) == LABEL_DECL
4362 && TREE_CODE (op1) == LABEL_DECL)
4363 return null_pointer_node;
4365 if (TREE_CODE (op0) == STRING_CST
4366 && TREE_CODE (op1) == STRING_CST
4367 && operand_equal_p (op0, op1, 1))
4368 return null_pointer_node;
4371 return NULL_TREE;
4374 /* Helper function of initializer_constant_valid_p.
4375 Return nonzero if VALUE is a valid constant-valued expression
4376 for use in initializing a static variable; one that can be an
4377 element of a "constant" initializer.
4379 Return null_pointer_node if the value is absolute;
4380 if it is relocatable, return the variable that determines the relocation.
4381 We assume that VALUE has been folded as much as possible;
4382 therefore, we do not need to check for such things as
4383 arithmetic-combinations of integers.
4385 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4387 static tree
4388 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4390 tree ret;
4392 switch (TREE_CODE (value))
4394 case CONSTRUCTOR:
4395 if (constructor_static_from_elts_p (value))
4397 unsigned HOST_WIDE_INT idx;
4398 tree elt;
4399 bool absolute = true;
4401 if (cache && cache[0] == value)
4402 return cache[1];
4403 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4405 tree reloc;
4406 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4407 NULL);
4408 if (!reloc
4409 /* An absolute value is required with reverse SSO. */
4410 || (reloc != null_pointer_node
4411 && TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (value))
4412 && !AGGREGATE_TYPE_P (TREE_TYPE (elt))))
4414 if (cache)
4416 cache[0] = value;
4417 cache[1] = NULL_TREE;
4419 return NULL_TREE;
4421 if (reloc != null_pointer_node)
4422 absolute = false;
4424 /* For a non-absolute relocation, there is no single
4425 variable that can be "the variable that determines the
4426 relocation." */
4427 if (cache)
4429 cache[0] = value;
4430 cache[1] = absolute ? null_pointer_node : error_mark_node;
4432 return absolute ? null_pointer_node : error_mark_node;
4435 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4437 case INTEGER_CST:
4438 case VECTOR_CST:
4439 case REAL_CST:
4440 case FIXED_CST:
4441 case STRING_CST:
4442 case COMPLEX_CST:
4443 return null_pointer_node;
4445 case ADDR_EXPR:
4446 case FDESC_EXPR:
4448 tree op0 = staticp (TREE_OPERAND (value, 0));
4449 if (op0)
4451 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4452 to be a constant, this is old-skool offsetof-like nonsense. */
4453 if (TREE_CODE (op0) == INDIRECT_REF
4454 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4455 return null_pointer_node;
4456 /* Taking the address of a nested function involves a trampoline,
4457 unless we don't need or want one. */
4458 if (TREE_CODE (op0) == FUNCTION_DECL
4459 && DECL_STATIC_CHAIN (op0)
4460 && !TREE_NO_TRAMPOLINE (value))
4461 return NULL_TREE;
4462 /* "&{...}" requires a temporary to hold the constructed
4463 object. */
4464 if (TREE_CODE (op0) == CONSTRUCTOR)
4465 return NULL_TREE;
4467 return op0;
4470 case NON_LVALUE_EXPR:
4471 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4472 endtype, cache);
4474 case VIEW_CONVERT_EXPR:
4476 tree src = TREE_OPERAND (value, 0);
4477 tree src_type = TREE_TYPE (src);
4478 tree dest_type = TREE_TYPE (value);
4480 /* Allow view-conversions from aggregate to non-aggregate type only
4481 if the bit pattern is fully preserved afterwards; otherwise, the
4482 RTL expander won't be able to apply a subsequent transformation
4483 to the underlying constructor. */
4484 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4486 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4487 return initializer_constant_valid_p_1 (src, endtype, cache);
4488 else
4489 return NULL_TREE;
4492 /* Allow all other kinds of view-conversion. */
4493 return initializer_constant_valid_p_1 (src, endtype, cache);
4496 CASE_CONVERT:
4498 tree src = TREE_OPERAND (value, 0);
4499 tree src_type = TREE_TYPE (src);
4500 tree dest_type = TREE_TYPE (value);
4502 /* Allow conversions between pointer types, floating-point
4503 types, and offset types. */
4504 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4505 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4506 || (TREE_CODE (dest_type) == OFFSET_TYPE
4507 && TREE_CODE (src_type) == OFFSET_TYPE))
4508 return initializer_constant_valid_p_1 (src, endtype, cache);
4510 /* Allow length-preserving conversions between integer types. */
4511 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4512 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4513 return initializer_constant_valid_p_1 (src, endtype, cache);
4515 /* Allow conversions between other integer types only if
4516 explicit value. Don't allow sign-extension to a type larger
4517 than word and pointer, there aren't relocations that would
4518 allow to sign extend it to a wider type. */
4519 if (INTEGRAL_TYPE_P (dest_type)
4520 && INTEGRAL_TYPE_P (src_type)
4521 && (TYPE_UNSIGNED (src_type)
4522 || TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type)
4523 || TYPE_PRECISION (dest_type) <= BITS_PER_WORD
4524 || TYPE_PRECISION (dest_type) <= POINTER_SIZE))
4526 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4527 if (inner == null_pointer_node)
4528 return null_pointer_node;
4529 break;
4532 /* Allow (int) &foo provided int is as wide as a pointer. */
4533 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4534 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4535 return initializer_constant_valid_p_1 (src, endtype, cache);
4537 /* Likewise conversions from int to pointers, but also allow
4538 conversions from 0. */
4539 if ((POINTER_TYPE_P (dest_type)
4540 || TREE_CODE (dest_type) == OFFSET_TYPE)
4541 && INTEGRAL_TYPE_P (src_type))
4543 if (TREE_CODE (src) == INTEGER_CST
4544 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4545 return null_pointer_node;
4546 if (integer_zerop (src))
4547 return null_pointer_node;
4548 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4549 return initializer_constant_valid_p_1 (src, endtype, cache);
4552 /* Allow conversions to struct or union types if the value
4553 inside is okay. */
4554 if (TREE_CODE (dest_type) == RECORD_TYPE
4555 || TREE_CODE (dest_type) == UNION_TYPE)
4556 return initializer_constant_valid_p_1 (src, endtype, cache);
4558 break;
4560 case POINTER_PLUS_EXPR:
4561 case PLUS_EXPR:
4562 /* Any valid floating-point constants will have been folded by now;
4563 with -frounding-math we hit this with addition of two constants. */
4564 if (TREE_CODE (endtype) == REAL_TYPE)
4565 return NULL_TREE;
4566 if (cache && cache[0] == value)
4567 return cache[1];
4568 if (! INTEGRAL_TYPE_P (endtype)
4569 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4571 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4572 tree valid0
4573 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4574 endtype, ncache);
4575 tree valid1
4576 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4577 endtype, ncache + 2);
4578 /* If either term is absolute, use the other term's relocation. */
4579 if (valid0 == null_pointer_node)
4580 ret = valid1;
4581 else if (valid1 == null_pointer_node)
4582 ret = valid0;
4583 /* Support narrowing pointer differences. */
4584 else
4585 ret = narrowing_initializer_constant_valid_p (value, endtype,
4586 ncache);
4588 else
4589 /* Support narrowing pointer differences. */
4590 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4591 if (cache)
4593 cache[0] = value;
4594 cache[1] = ret;
4596 return ret;
4598 case MINUS_EXPR:
4599 if (TREE_CODE (endtype) == REAL_TYPE)
4600 return NULL_TREE;
4601 if (cache && cache[0] == value)
4602 return cache[1];
4603 if (! INTEGRAL_TYPE_P (endtype)
4604 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4606 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4607 tree valid0
4608 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4609 endtype, ncache);
4610 tree valid1
4611 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4612 endtype, ncache + 2);
4613 /* Win if second argument is absolute. */
4614 if (valid1 == null_pointer_node)
4615 ret = valid0;
4616 /* Win if both arguments have the same relocation.
4617 Then the value is absolute. */
4618 else if (valid0 == valid1 && valid0 != 0)
4619 ret = null_pointer_node;
4620 /* Since GCC guarantees that string constants are unique in the
4621 generated code, a subtraction between two copies of the same
4622 constant string is absolute. */
4623 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4624 && valid1 && TREE_CODE (valid1) == STRING_CST
4625 && operand_equal_p (valid0, valid1, 1))
4626 ret = null_pointer_node;
4627 /* Support narrowing differences. */
4628 else
4629 ret = narrowing_initializer_constant_valid_p (value, endtype,
4630 ncache);
4632 else
4633 /* Support narrowing differences. */
4634 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4635 if (cache)
4637 cache[0] = value;
4638 cache[1] = ret;
4640 return ret;
4642 default:
4643 break;
4646 return NULL_TREE;
4649 /* Return nonzero if VALUE is a valid constant-valued expression
4650 for use in initializing a static variable; one that can be an
4651 element of a "constant" initializer.
4653 Return null_pointer_node if the value is absolute;
4654 if it is relocatable, return the variable that determines the relocation.
4655 We assume that VALUE has been folded as much as possible;
4656 therefore, we do not need to check for such things as
4657 arithmetic-combinations of integers. */
4658 tree
4659 initializer_constant_valid_p (tree value, tree endtype, bool reverse)
4661 tree reloc = initializer_constant_valid_p_1 (value, endtype, NULL);
4663 /* An absolute value is required with reverse storage order. */
4664 if (reloc
4665 && reloc != null_pointer_node
4666 && reverse
4667 && !AGGREGATE_TYPE_P (endtype)
4668 && !VECTOR_TYPE_P (endtype))
4669 reloc = NULL_TREE;
4671 return reloc;
4674 /* Return true if VALUE is a valid constant-valued expression
4675 for use in initializing a static bit-field; one that can be
4676 an element of a "constant" initializer. */
4678 bool
4679 initializer_constant_valid_for_bitfield_p (tree value)
4681 /* For bitfields we support integer constants or possibly nested aggregates
4682 of such. */
4683 switch (TREE_CODE (value))
4685 case CONSTRUCTOR:
4687 unsigned HOST_WIDE_INT idx;
4688 tree elt;
4690 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4691 if (!initializer_constant_valid_for_bitfield_p (elt))
4692 return false;
4693 return true;
4696 case INTEGER_CST:
4697 case REAL_CST:
4698 return true;
4700 case VIEW_CONVERT_EXPR:
4701 case NON_LVALUE_EXPR:
4702 return
4703 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4705 default:
4706 break;
4709 return false;
4712 /* output_constructor outer state of relevance in recursive calls, typically
4713 for nested aggregate bitfields. */
4715 struct oc_outer_state {
4716 unsigned int bit_offset; /* current position in ... */
4717 int byte; /* ... the outer byte buffer. */
4720 static unsigned HOST_WIDE_INT
4721 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int, bool,
4722 oc_outer_state *);
4724 /* Output assembler code for constant EXP, with no label.
4725 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4726 Assumes output_addressed_constants has been done on EXP already.
4728 Generate at least SIZE bytes of assembler data, padding at the end
4729 with zeros if necessary. SIZE must always be specified. The returned
4730 value is the actual number of bytes of assembler data generated, which
4731 may be bigger than SIZE if the object contains a variable length field.
4733 SIZE is important for structure constructors,
4734 since trailing members may have been omitted from the constructor.
4735 It is also important for initialization of arrays from string constants
4736 since the full length of the string constant might not be wanted.
4737 It is also needed for initialization of unions, where the initializer's
4738 type is just one member, and that may not be as long as the union.
4740 There a case in which we would fail to output exactly SIZE bytes:
4741 for a structure constructor that wants to produce more than SIZE bytes.
4742 But such constructors will never be generated for any possible input.
4744 ALIGN is the alignment of the data in bits.
4746 If REVERSE is true, EXP is output in reverse storage order. */
4748 static unsigned HOST_WIDE_INT
4749 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align,
4750 bool reverse)
4752 enum tree_code code;
4753 unsigned HOST_WIDE_INT thissize;
4754 rtx cst;
4756 if (size == 0 || flag_syntax_only)
4757 return size;
4759 /* See if we're trying to initialize a pointer in a non-default mode
4760 to the address of some declaration somewhere. If the target says
4761 the mode is valid for pointers, assume the target has a way of
4762 resolving it. */
4763 if (TREE_CODE (exp) == NOP_EXPR
4764 && POINTER_TYPE_P (TREE_TYPE (exp))
4765 && targetm.addr_space.valid_pointer_mode
4766 (TYPE_MODE (TREE_TYPE (exp)),
4767 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4769 tree saved_type = TREE_TYPE (exp);
4771 /* Peel off any intermediate conversions-to-pointer for valid
4772 pointer modes. */
4773 while (TREE_CODE (exp) == NOP_EXPR
4774 && POINTER_TYPE_P (TREE_TYPE (exp))
4775 && targetm.addr_space.valid_pointer_mode
4776 (TYPE_MODE (TREE_TYPE (exp)),
4777 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4778 exp = TREE_OPERAND (exp, 0);
4780 /* If what we're left with is the address of something, we can
4781 convert the address to the final type and output it that
4782 way. */
4783 if (TREE_CODE (exp) == ADDR_EXPR)
4784 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4785 /* Likewise for constant ints. */
4786 else if (TREE_CODE (exp) == INTEGER_CST)
4787 exp = fold_convert (saved_type, exp);
4791 /* Eliminate any conversions since we'll be outputting the underlying
4792 constant. */
4793 while (CONVERT_EXPR_P (exp)
4794 || TREE_CODE (exp) == NON_LVALUE_EXPR
4795 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4797 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4798 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4800 /* Make sure eliminating the conversion is really a no-op, except with
4801 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4802 union types to allow for Ada unchecked unions. */
4803 if (type_size > op_size
4804 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4805 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4806 /* Keep the conversion. */
4807 break;
4808 else
4809 exp = TREE_OPERAND (exp, 0);
4812 code = TREE_CODE (TREE_TYPE (exp));
4813 thissize = int_size_in_bytes (TREE_TYPE (exp));
4815 /* Allow a constructor with no elements for any data type.
4816 This means to fill the space with zeros. */
4817 if (TREE_CODE (exp) == CONSTRUCTOR
4818 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4820 assemble_zeros (size);
4821 return size;
4824 if (TREE_CODE (exp) == FDESC_EXPR)
4826 #ifdef ASM_OUTPUT_FDESC
4827 HOST_WIDE_INT part = tree_to_shwi (TREE_OPERAND (exp, 1));
4828 tree decl = TREE_OPERAND (exp, 0);
4829 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4830 #else
4831 gcc_unreachable ();
4832 #endif
4833 return size;
4836 /* Now output the underlying data. If we've handling the padding, return.
4837 Otherwise, break and ensure SIZE is the size written. */
4838 switch (code)
4840 case BOOLEAN_TYPE:
4841 case INTEGER_TYPE:
4842 case ENUMERAL_TYPE:
4843 case POINTER_TYPE:
4844 case REFERENCE_TYPE:
4845 case OFFSET_TYPE:
4846 case FIXED_POINT_TYPE:
4847 case POINTER_BOUNDS_TYPE:
4848 case NULLPTR_TYPE:
4849 cst = expand_expr (exp, NULL_RTX, VOIDmode, EXPAND_INITIALIZER);
4850 if (reverse)
4851 cst = flip_storage_order (TYPE_MODE (TREE_TYPE (exp)), cst);
4852 if (!assemble_integer (cst, MIN (size, thissize), align, 0))
4853 error ("initializer for integer/fixed-point value is too complicated");
4854 break;
4856 case REAL_TYPE:
4857 if (TREE_CODE (exp) != REAL_CST)
4858 error ("initializer for floating value is not a floating constant");
4859 else
4860 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)),
4861 align, reverse);
4862 break;
4864 case COMPLEX_TYPE:
4865 output_constant (TREE_REALPART (exp), thissize / 2, align, reverse);
4866 output_constant (TREE_IMAGPART (exp), thissize / 2,
4867 min_align (align, BITS_PER_UNIT * (thissize / 2)),
4868 reverse);
4869 break;
4871 case ARRAY_TYPE:
4872 case VECTOR_TYPE:
4873 switch (TREE_CODE (exp))
4875 case CONSTRUCTOR:
4876 return output_constructor (exp, size, align, reverse, NULL);
4877 case STRING_CST:
4878 thissize
4879 = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4880 assemble_string (TREE_STRING_POINTER (exp), thissize);
4881 break;
4882 case VECTOR_CST:
4884 machine_mode inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4885 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4886 int elt_size = GET_MODE_SIZE (inner);
4887 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align,
4888 reverse);
4889 thissize = elt_size;
4890 for (unsigned int i = 1; i < VECTOR_CST_NELTS (exp); i++)
4892 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign,
4893 reverse);
4894 thissize += elt_size;
4896 break;
4898 default:
4899 gcc_unreachable ();
4901 break;
4903 case RECORD_TYPE:
4904 case UNION_TYPE:
4905 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4906 return output_constructor (exp, size, align, reverse, NULL);
4908 case ERROR_MARK:
4909 return 0;
4911 default:
4912 gcc_unreachable ();
4915 if (size > thissize)
4916 assemble_zeros (size - thissize);
4918 return size;
4921 /* Subroutine of output_constructor, used for computing the size of
4922 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4923 type with an unspecified upper bound. */
4925 static unsigned HOST_WIDE_INT
4926 array_size_for_constructor (tree val)
4928 tree max_index;
4929 unsigned HOST_WIDE_INT cnt;
4930 tree index, value, tmp;
4931 offset_int i;
4933 /* This code used to attempt to handle string constants that are not
4934 arrays of single-bytes, but nothing else does, so there's no point in
4935 doing it here. */
4936 if (TREE_CODE (val) == STRING_CST)
4937 return TREE_STRING_LENGTH (val);
4939 max_index = NULL_TREE;
4940 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
4942 if (TREE_CODE (index) == RANGE_EXPR)
4943 index = TREE_OPERAND (index, 1);
4944 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
4945 max_index = index;
4948 if (max_index == NULL_TREE)
4949 return 0;
4951 /* Compute the total number of array elements. */
4952 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
4953 i = wi::to_offset (max_index) - wi::to_offset (tmp) + 1;
4955 /* Multiply by the array element unit size to find number of bytes. */
4956 i *= wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
4958 gcc_assert (wi::fits_uhwi_p (i));
4959 return i.to_uhwi ();
4962 /* Other datastructures + helpers for output_constructor. */
4964 /* output_constructor local state to support interaction with helpers. */
4966 struct oc_local_state {
4968 /* Received arguments. */
4969 tree exp; /* Constructor expression. */
4970 tree type; /* Type of constructor expression. */
4971 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */
4972 unsigned int align; /* Known initial alignment. */
4973 tree min_index; /* Lower bound if specified for an array. */
4975 /* Output processing state. */
4976 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */
4977 int byte; /* Part of a bitfield byte yet to be output. */
4978 int last_relative_index; /* Implicit or explicit index of the last
4979 array element output within a bitfield. */
4980 bool byte_buffer_in_use; /* Whether BYTE is in use. */
4981 bool reverse; /* Whether reverse storage order is in use. */
4983 /* Current element. */
4984 tree field; /* Current field decl in a record. */
4985 tree val; /* Current element value. */
4986 tree index; /* Current element index. */
4990 /* Helper for output_constructor. From the current LOCAL state, output a
4991 RANGE_EXPR element. */
4993 static void
4994 output_constructor_array_range (oc_local_state *local)
4996 unsigned HOST_WIDE_INT fieldsize
4997 = int_size_in_bytes (TREE_TYPE (local->type));
4999 HOST_WIDE_INT lo_index
5000 = tree_to_shwi (TREE_OPERAND (local->index, 0));
5001 HOST_WIDE_INT hi_index
5002 = tree_to_shwi (TREE_OPERAND (local->index, 1));
5003 HOST_WIDE_INT index;
5005 unsigned int align2
5006 = min_align (local->align, fieldsize * BITS_PER_UNIT);
5008 for (index = lo_index; index <= hi_index; index++)
5010 /* Output the element's initial value. */
5011 if (local->val == NULL_TREE)
5012 assemble_zeros (fieldsize);
5013 else
5014 fieldsize
5015 = output_constant (local->val, fieldsize, align2, local->reverse);
5017 /* Count its size. */
5018 local->total_bytes += fieldsize;
5022 /* Helper for output_constructor. From the current LOCAL state, output a
5023 field element that is not true bitfield or part of an outer one. */
5025 static void
5026 output_constructor_regular_field (oc_local_state *local)
5028 /* Field size and position. Since this structure is static, we know the
5029 positions are constant. */
5030 unsigned HOST_WIDE_INT fieldsize;
5031 HOST_WIDE_INT fieldpos;
5033 unsigned int align2;
5035 /* Output any buffered-up bit-fields preceding this element. */
5036 if (local->byte_buffer_in_use)
5038 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5039 local->total_bytes++;
5040 local->byte_buffer_in_use = false;
5043 if (local->index != NULL_TREE)
5045 /* Perform the index calculation in modulo arithmetic but
5046 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
5047 but we are using an unsigned sizetype. */
5048 unsigned prec = TYPE_PRECISION (sizetype);
5049 offset_int idx = wi::sext (wi::to_offset (local->index)
5050 - wi::to_offset (local->min_index), prec);
5051 fieldpos = (idx * wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (local->val))))
5052 .to_short_addr ();
5054 else if (local->field != NULL_TREE)
5055 fieldpos = int_byte_position (local->field);
5056 else
5057 fieldpos = 0;
5059 /* Advance to offset of this element.
5060 Note no alignment needed in an array, since that is guaranteed
5061 if each element has the proper size. */
5062 if (local->field != NULL_TREE || local->index != NULL_TREE)
5064 if (fieldpos > local->total_bytes)
5066 assemble_zeros (fieldpos - local->total_bytes);
5067 local->total_bytes = fieldpos;
5069 else
5070 /* Must not go backwards. */
5071 gcc_assert (fieldpos == local->total_bytes);
5074 /* Find the alignment of this element. */
5075 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
5077 /* Determine size this element should occupy. */
5078 if (local->field)
5080 fieldsize = 0;
5082 /* If this is an array with an unspecified upper bound,
5083 the initializer determines the size. */
5084 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
5085 but we cannot do this until the deprecated support for
5086 initializing zero-length array members is removed. */
5087 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
5088 && (!TYPE_DOMAIN (TREE_TYPE (local->field))
5089 || !TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field)))))
5091 fieldsize = array_size_for_constructor (local->val);
5092 /* Given a non-empty initialization, this field had better
5093 be last. Given a flexible array member, the next field
5094 on the chain is a TYPE_DECL of the enclosing struct. */
5095 const_tree next = DECL_CHAIN (local->field);
5096 gcc_assert (!fieldsize || !next || TREE_CODE (next) != FIELD_DECL);
5098 else
5099 fieldsize = tree_to_uhwi (DECL_SIZE_UNIT (local->field));
5101 else
5102 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
5104 /* Output the element's initial value. */
5105 if (local->val == NULL_TREE)
5106 assemble_zeros (fieldsize);
5107 else
5108 fieldsize
5109 = output_constant (local->val, fieldsize, align2, local->reverse);
5111 /* Count its size. */
5112 local->total_bytes += fieldsize;
5115 /* Helper for output_constructor. From the LOCAL state, output an element
5116 that is a true bitfield or part of an outer one. BIT_OFFSET is the offset
5117 from the start of a possibly ongoing outer byte buffer. */
5119 static void
5120 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
5122 /* Bit size of this element. */
5123 HOST_WIDE_INT ebitsize
5124 = (local->field
5125 ? tree_to_uhwi (DECL_SIZE (local->field))
5126 : tree_to_uhwi (TYPE_SIZE (TREE_TYPE (local->type))));
5128 /* Relative index of this element if this is an array component. */
5129 HOST_WIDE_INT relative_index
5130 = (!local->field
5131 ? (local->index
5132 ? (tree_to_shwi (local->index)
5133 - tree_to_shwi (local->min_index))
5134 : local->last_relative_index + 1)
5135 : 0);
5137 /* Bit position of this element from the start of the containing
5138 constructor. */
5139 HOST_WIDE_INT constructor_relative_ebitpos
5140 = (local->field
5141 ? int_bit_position (local->field)
5142 : ebitsize * relative_index);
5144 /* Bit position of this element from the start of a possibly ongoing
5145 outer byte buffer. */
5146 HOST_WIDE_INT byte_relative_ebitpos
5147 = bit_offset + constructor_relative_ebitpos;
5149 /* From the start of a possibly ongoing outer byte buffer, offsets to
5150 the first bit of this element and to the first bit past the end of
5151 this element. */
5152 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
5153 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
5155 local->last_relative_index = relative_index;
5157 if (local->val == NULL_TREE)
5158 local->val = integer_zero_node;
5160 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
5161 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
5162 local->val = TREE_OPERAND (local->val, 0);
5164 if (TREE_CODE (local->val) != INTEGER_CST
5165 && TREE_CODE (local->val) != CONSTRUCTOR)
5167 error ("invalid initial value for member %qE", DECL_NAME (local->field));
5168 return;
5171 /* If this field does not start in this (or next) byte, skip some bytes. */
5172 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5174 /* Output remnant of any bit field in previous bytes. */
5175 if (local->byte_buffer_in_use)
5177 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5178 local->total_bytes++;
5179 local->byte_buffer_in_use = false;
5182 /* If still not at proper byte, advance to there. */
5183 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5185 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
5186 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
5187 local->total_bytes = next_offset / BITS_PER_UNIT;
5191 /* Set up the buffer if necessary. */
5192 if (!local->byte_buffer_in_use)
5194 local->byte = 0;
5195 if (ebitsize > 0)
5196 local->byte_buffer_in_use = true;
5199 /* If this is nested constructor, recurse passing the bit offset and the
5200 pending data, then retrieve the new pending data afterwards. */
5201 if (TREE_CODE (local->val) == CONSTRUCTOR)
5203 oc_outer_state temp_state;
5204 temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5205 temp_state.byte = local->byte;
5206 local->total_bytes
5207 += output_constructor (local->val, 0, 0, local->reverse, &temp_state);
5208 local->byte = temp_state.byte;
5209 return;
5212 /* Otherwise, we must split the element into pieces that fall within
5213 separate bytes, and combine each byte with previous or following
5214 bit-fields. */
5215 while (next_offset < end_offset)
5217 int this_time;
5218 int shift;
5219 HOST_WIDE_INT value;
5220 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5221 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5223 /* Advance from byte to byte within this element when necessary. */
5224 while (next_byte != local->total_bytes)
5226 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5227 local->total_bytes++;
5228 local->byte = 0;
5231 /* Number of bits we can process at once (all part of the same byte). */
5232 this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5233 if (local->reverse ? !BYTES_BIG_ENDIAN : BYTES_BIG_ENDIAN)
5235 /* For big-endian data, take the most significant bits (of the
5236 bits that are significant) first and put them into bytes from
5237 the most significant end. */
5238 shift = end_offset - next_offset - this_time;
5240 /* Don't try to take a bunch of bits that cross
5241 the word boundary in the INTEGER_CST. We can
5242 only select bits from one element. */
5243 if ((shift / HOST_BITS_PER_WIDE_INT)
5244 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5246 const int end = shift + this_time - 1;
5247 shift = end & -HOST_BITS_PER_WIDE_INT;
5248 this_time = end - shift + 1;
5251 /* Now get the bits from the appropriate constant word. */
5252 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5253 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5255 /* Get the result. This works only when:
5256 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5257 local->byte |= (((value >> shift)
5258 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5259 << (BITS_PER_UNIT - this_time - next_bit));
5261 else
5263 /* On little-endian machines, take the least significant bits of
5264 the value first and pack them starting at the least significant
5265 bits of the bytes. */
5266 shift = next_offset - byte_relative_ebitpos;
5268 /* Don't try to take a bunch of bits that cross
5269 the word boundary in the INTEGER_CST. We can
5270 only select bits from one element. */
5271 if ((shift / HOST_BITS_PER_WIDE_INT)
5272 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5273 this_time
5274 = HOST_BITS_PER_WIDE_INT - (shift & (HOST_BITS_PER_WIDE_INT - 1));
5276 /* Now get the bits from the appropriate constant word. */
5277 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5278 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5280 /* Get the result. This works only when:
5281 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5282 local->byte |= (((value >> shift)
5283 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5284 << next_bit);
5287 next_offset += this_time;
5288 local->byte_buffer_in_use = true;
5292 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5293 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5294 caller output state of relevance in recursive invocations. */
5296 static unsigned HOST_WIDE_INT
5297 output_constructor (tree exp, unsigned HOST_WIDE_INT size, unsigned int align,
5298 bool reverse, oc_outer_state *outer)
5300 unsigned HOST_WIDE_INT cnt;
5301 constructor_elt *ce;
5302 oc_local_state local;
5304 /* Setup our local state to communicate with helpers. */
5305 local.exp = exp;
5306 local.type = TREE_TYPE (exp);
5307 local.size = size;
5308 local.align = align;
5309 if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5310 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5311 else
5312 local.min_index = integer_zero_node;
5314 local.total_bytes = 0;
5315 local.byte_buffer_in_use = outer != NULL;
5316 local.byte = outer ? outer->byte : 0;
5317 local.last_relative_index = -1;
5318 /* The storage order is specified for every aggregate type. */
5319 if (AGGREGATE_TYPE_P (local.type))
5320 local.reverse = TYPE_REVERSE_STORAGE_ORDER (local.type);
5321 else
5322 local.reverse = reverse;
5324 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5326 /* As CE goes through the elements of the constant, FIELD goes through the
5327 structure fields if the constant is a structure. If the constant is a
5328 union, we override this by getting the field from the TREE_LIST element.
5329 But the constant could also be an array. Then FIELD is zero.
5331 There is always a maximum of one element in the chain LINK for unions
5332 (even if the initializer in a source program incorrectly contains
5333 more one). */
5335 if (TREE_CODE (local.type) == RECORD_TYPE)
5336 local.field = TYPE_FIELDS (local.type);
5337 else
5338 local.field = NULL_TREE;
5340 for (cnt = 0;
5341 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5342 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5344 local.val = ce->value;
5345 local.index = NULL_TREE;
5347 /* The element in a union constructor specifies the proper field
5348 or index. */
5349 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5350 local.field = ce->index;
5352 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5353 local.index = ce->index;
5355 if (local.field && flag_verbose_asm)
5356 fprintf (asm_out_file, "%s %s:\n",
5357 ASM_COMMENT_START,
5358 DECL_NAME (local.field)
5359 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5360 : "<anonymous>");
5362 /* Eliminate the marker that makes a cast not be an lvalue. */
5363 if (local.val != NULL_TREE)
5364 STRIP_NOPS (local.val);
5366 /* Output the current element, using the appropriate helper ... */
5368 /* For an array slice not part of an outer bitfield. */
5369 if (!outer
5370 && local.index != NULL_TREE
5371 && TREE_CODE (local.index) == RANGE_EXPR)
5372 output_constructor_array_range (&local);
5374 /* For a field that is neither a true bitfield nor part of an outer one,
5375 known to be at least byte aligned and multiple-of-bytes long. */
5376 else if (!outer
5377 && (local.field == NULL_TREE
5378 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5379 output_constructor_regular_field (&local);
5381 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5382 supported for scalar fields, so we may need to convert first. */
5383 else
5385 if (TREE_CODE (local.val) == REAL_CST)
5386 local.val
5387 = fold_unary (VIEW_CONVERT_EXPR,
5388 build_nonstandard_integer_type
5389 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5390 local.val);
5391 output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5395 /* If we are not at toplevel, save the pending data for our caller.
5396 Otherwise output the pending data and padding zeros as needed. */
5397 if (outer)
5398 outer->byte = local.byte;
5399 else
5401 if (local.byte_buffer_in_use)
5403 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5404 local.total_bytes++;
5407 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5409 assemble_zeros (local.size - local.total_bytes);
5410 local.total_bytes = local.size;
5414 return local.total_bytes;
5417 /* Mark DECL as weak. */
5419 static void
5420 mark_weak (tree decl)
5422 if (DECL_WEAK (decl))
5423 return;
5425 struct symtab_node *n = symtab_node::get (decl);
5426 if (n && n->refuse_visibility_changes)
5427 error ("%+qD declared weak after being used", decl);
5428 DECL_WEAK (decl) = 1;
5430 if (DECL_RTL_SET_P (decl)
5431 && MEM_P (DECL_RTL (decl))
5432 && XEXP (DECL_RTL (decl), 0)
5433 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5434 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5437 /* Merge weak status between NEWDECL and OLDDECL. */
5439 void
5440 merge_weak (tree newdecl, tree olddecl)
5442 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5444 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5446 tree *pwd;
5447 /* We put the NEWDECL on the weak_decls list at some point
5448 and OLDDECL as well. Keep just OLDDECL on the list. */
5449 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5450 if (TREE_VALUE (*pwd) == newdecl)
5452 *pwd = TREE_CHAIN (*pwd);
5453 break;
5456 return;
5459 if (DECL_WEAK (newdecl))
5461 tree wd;
5463 /* NEWDECL is weak, but OLDDECL is not. */
5465 /* If we already output the OLDDECL, we're in trouble; we can't
5466 go back and make it weak. This should never happen in
5467 unit-at-a-time compilation. */
5468 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5470 /* If we've already generated rtl referencing OLDDECL, we may
5471 have done so in a way that will not function properly with
5472 a weak symbol. Again in unit-at-a-time this should be
5473 impossible. */
5474 gcc_assert (!TREE_USED (olddecl)
5475 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5477 /* PR 49899: You cannot convert a static function into a weak, public function. */
5478 if (! TREE_PUBLIC (olddecl) && TREE_PUBLIC (newdecl))
5479 error ("weak declaration of %q+D being applied to a already "
5480 "existing, static definition", newdecl);
5482 if (TARGET_SUPPORTS_WEAK)
5484 /* We put the NEWDECL on the weak_decls list at some point.
5485 Replace it with the OLDDECL. */
5486 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5487 if (TREE_VALUE (wd) == newdecl)
5489 TREE_VALUE (wd) = olddecl;
5490 break;
5492 /* We may not find the entry on the list. If NEWDECL is a
5493 weak alias, then we will have already called
5494 globalize_decl to remove the entry; in that case, we do
5495 not need to do anything. */
5498 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5499 mark_weak (olddecl);
5501 else
5502 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5503 weak. Just update NEWDECL to indicate that it's weak too. */
5504 mark_weak (newdecl);
5507 /* Declare DECL to be a weak symbol. */
5509 void
5510 declare_weak (tree decl)
5512 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5513 if (! TREE_PUBLIC (decl))
5515 error ("weak declaration of %q+D must be public", decl);
5516 return;
5518 else if (!TARGET_SUPPORTS_WEAK)
5519 warning (0, "weak declaration of %q+D not supported", decl);
5521 mark_weak (decl);
5522 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5523 DECL_ATTRIBUTES (decl)
5524 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5527 static void
5528 weak_finish_1 (tree decl)
5530 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5531 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5532 #endif
5534 if (! TREE_USED (decl))
5535 return;
5537 #ifdef ASM_WEAKEN_DECL
5538 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5539 #else
5540 #ifdef ASM_WEAKEN_LABEL
5541 ASM_WEAKEN_LABEL (asm_out_file, name);
5542 #else
5543 #ifdef ASM_OUTPUT_WEAK_ALIAS
5545 static bool warn_once = 0;
5546 if (! warn_once)
5548 warning (0, "only weak aliases are supported in this configuration");
5549 warn_once = 1;
5551 return;
5553 #endif
5554 #endif
5555 #endif
5558 /* Fiven an assembly name, find the decl it is associated with. */
5559 static tree
5560 find_decl (tree target)
5562 symtab_node *node = symtab_node::get_for_asmname (target);
5563 if (node)
5564 return node->decl;
5565 return NULL_TREE;
5568 /* This TREE_LIST contains weakref targets. */
5570 static GTY(()) tree weakref_targets;
5572 /* Emit any pending weak declarations. */
5574 void
5575 weak_finish (void)
5577 tree t;
5579 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5581 tree alias_decl = TREE_PURPOSE (t);
5582 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5584 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5585 /* Remove alias_decl from the weak list, but leave entries for
5586 the target alone. */
5587 target = NULL_TREE;
5588 #ifndef ASM_OUTPUT_WEAKREF
5589 else if (! TREE_SYMBOL_REFERENCED (target))
5591 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5592 defined, otherwise we and weak_finish_1 would use
5593 different macros. */
5594 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5595 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5596 # else
5597 tree decl = find_decl (target);
5599 if (! decl)
5601 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5602 TREE_CODE (alias_decl), target,
5603 TREE_TYPE (alias_decl));
5605 DECL_EXTERNAL (decl) = 1;
5606 TREE_PUBLIC (decl) = 1;
5607 DECL_ARTIFICIAL (decl) = 1;
5608 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5609 TREE_USED (decl) = 1;
5612 weak_finish_1 (decl);
5613 # endif
5615 #endif
5618 tree *p;
5619 tree t2;
5621 /* Remove the alias and the target from the pending weak list
5622 so that we do not emit any .weak directives for the former,
5623 nor multiple .weak directives for the latter. */
5624 for (p = &weak_decls; (t2 = *p) ; )
5626 if (TREE_VALUE (t2) == alias_decl
5627 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5628 *p = TREE_CHAIN (t2);
5629 else
5630 p = &TREE_CHAIN (t2);
5633 /* Remove other weakrefs to the same target, to speed things up. */
5634 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5636 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5637 *p = TREE_CHAIN (t2);
5638 else
5639 p = &TREE_CHAIN (t2);
5644 for (t = weak_decls; t; t = TREE_CHAIN (t))
5646 tree decl = TREE_VALUE (t);
5648 weak_finish_1 (decl);
5652 /* Emit the assembly bits to indicate that DECL is globally visible. */
5654 static void
5655 globalize_decl (tree decl)
5658 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5659 if (DECL_WEAK (decl))
5661 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5662 tree *p, t;
5664 #ifdef ASM_WEAKEN_DECL
5665 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5666 #else
5667 ASM_WEAKEN_LABEL (asm_out_file, name);
5668 #endif
5670 /* Remove this function from the pending weak list so that
5671 we do not emit multiple .weak directives for it. */
5672 for (p = &weak_decls; (t = *p) ; )
5674 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5675 *p = TREE_CHAIN (t);
5676 else
5677 p = &TREE_CHAIN (t);
5680 /* Remove weakrefs to the same target from the pending weakref
5681 list, for the same reason. */
5682 for (p = &weakref_targets; (t = *p) ; )
5684 if (DECL_ASSEMBLER_NAME (decl)
5685 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5686 *p = TREE_CHAIN (t);
5687 else
5688 p = &TREE_CHAIN (t);
5691 return;
5693 #endif
5695 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5698 vec<alias_pair, va_gc> *alias_pairs;
5700 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5701 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5702 tree node is DECL to have the value of the tree node TARGET. */
5704 void
5705 do_assemble_alias (tree decl, tree target)
5707 tree id;
5709 /* Emulated TLS had better not get this var. */
5710 gcc_assert (!(!targetm.have_tls
5711 && VAR_P (decl)
5712 && DECL_THREAD_LOCAL_P (decl)));
5714 if (TREE_ASM_WRITTEN (decl))
5715 return;
5717 id = DECL_ASSEMBLER_NAME (decl);
5718 ultimate_transparent_alias_target (&id);
5719 ultimate_transparent_alias_target (&target);
5721 /* We must force creation of DECL_RTL for debug info generation, even though
5722 we don't use it here. */
5723 make_decl_rtl (decl);
5725 TREE_ASM_WRITTEN (decl) = 1;
5726 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5727 TREE_ASM_WRITTEN (id) = 1;
5729 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5731 if (!TREE_SYMBOL_REFERENCED (target))
5732 weakref_targets = tree_cons (decl, target, weakref_targets);
5734 #ifdef ASM_OUTPUT_WEAKREF
5735 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5736 IDENTIFIER_POINTER (id),
5737 IDENTIFIER_POINTER (target));
5738 #else
5739 if (!TARGET_SUPPORTS_WEAK)
5741 error_at (DECL_SOURCE_LOCATION (decl),
5742 "weakref is not supported in this configuration");
5743 return;
5745 #endif
5746 return;
5749 #ifdef ASM_OUTPUT_DEF
5750 tree orig_decl = decl;
5752 if (TREE_CODE (decl) == FUNCTION_DECL
5753 && cgraph_node::get (decl)->instrumentation_clone
5754 && cgraph_node::get (decl)->instrumented_version)
5755 orig_decl = cgraph_node::get (decl)->instrumented_version->decl;
5757 /* Make name accessible from other files, if appropriate. */
5759 if (TREE_PUBLIC (decl) || TREE_PUBLIC (orig_decl))
5761 globalize_decl (decl);
5762 maybe_assemble_visibility (decl);
5764 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5766 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5767 if (targetm.has_ifunc_p ())
5768 ASM_OUTPUT_TYPE_DIRECTIVE
5769 (asm_out_file, IDENTIFIER_POINTER (id),
5770 IFUNC_ASM_TYPE);
5771 else
5772 #endif
5773 error_at (DECL_SOURCE_LOCATION (decl),
5774 "ifunc is not supported on this target");
5777 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5778 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5779 # else
5780 ASM_OUTPUT_DEF (asm_out_file,
5781 IDENTIFIER_POINTER (id),
5782 IDENTIFIER_POINTER (target));
5783 # endif
5784 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5786 const char *name;
5787 tree *p, t;
5789 name = IDENTIFIER_POINTER (id);
5790 # ifdef ASM_WEAKEN_DECL
5791 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5792 # else
5793 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5794 # endif
5795 /* Remove this function from the pending weak list so that
5796 we do not emit multiple .weak directives for it. */
5797 for (p = &weak_decls; (t = *p) ; )
5798 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t))
5799 || id == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5800 *p = TREE_CHAIN (t);
5801 else
5802 p = &TREE_CHAIN (t);
5804 /* Remove weakrefs to the same target from the pending weakref
5805 list, for the same reason. */
5806 for (p = &weakref_targets; (t = *p) ; )
5808 if (id == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5809 *p = TREE_CHAIN (t);
5810 else
5811 p = &TREE_CHAIN (t);
5814 #endif
5817 /* Emit an assembler directive to make the symbol for DECL an alias to
5818 the symbol for TARGET. */
5820 void
5821 assemble_alias (tree decl, tree target)
5823 tree target_decl;
5825 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5827 tree alias = DECL_ASSEMBLER_NAME (decl);
5829 ultimate_transparent_alias_target (&target);
5831 if (alias == target)
5832 error ("weakref %q+D ultimately targets itself", decl);
5833 if (TREE_PUBLIC (decl))
5834 error ("weakref %q+D must have static linkage", decl);
5836 else
5838 #if !defined (ASM_OUTPUT_DEF)
5839 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5840 error_at (DECL_SOURCE_LOCATION (decl),
5841 "alias definitions not supported in this configuration");
5842 TREE_ASM_WRITTEN (decl) = 1;
5843 return;
5844 # else
5845 if (!DECL_WEAK (decl))
5847 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5848 error_at (DECL_SOURCE_LOCATION (decl),
5849 "ifunc is not supported in this configuration");
5850 else
5851 error_at (DECL_SOURCE_LOCATION (decl),
5852 "only weak aliases are supported in this configuration");
5853 TREE_ASM_WRITTEN (decl) = 1;
5854 return;
5856 # endif
5857 #endif
5859 TREE_USED (decl) = 1;
5861 /* Allow aliases to aliases. */
5862 if (TREE_CODE (decl) == FUNCTION_DECL)
5863 cgraph_node::get_create (decl)->alias = true;
5864 else
5865 varpool_node::get_create (decl)->alias = true;
5867 /* If the target has already been emitted, we don't have to queue the
5868 alias. This saves a tad of memory. */
5869 if (symtab->global_info_ready)
5870 target_decl = find_decl (target);
5871 else
5872 target_decl= NULL;
5873 if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5874 || symtab->state >= EXPANSION)
5875 do_assemble_alias (decl, target);
5876 else
5878 alias_pair p = {decl, target};
5879 vec_safe_push (alias_pairs, p);
5883 /* Record and output a table of translations from original function
5884 to its transaction aware clone. Note that tm_pure functions are
5885 considered to be their own clone. */
5887 struct tm_clone_hasher : ggc_cache_ptr_hash<tree_map>
5889 static hashval_t hash (tree_map *m) { return tree_map_hash (m); }
5890 static bool equal (tree_map *a, tree_map *b) { return tree_map_eq (a, b); }
5892 static int
5893 keep_cache_entry (tree_map *&e)
5895 return ggc_marked_p (e->base.from);
5899 static GTY((cache)) hash_table<tm_clone_hasher> *tm_clone_hash;
5901 void
5902 record_tm_clone_pair (tree o, tree n)
5904 struct tree_map **slot, *h;
5906 if (tm_clone_hash == NULL)
5907 tm_clone_hash = hash_table<tm_clone_hasher>::create_ggc (32);
5909 h = ggc_alloc<tree_map> ();
5910 h->hash = htab_hash_pointer (o);
5911 h->base.from = o;
5912 h->to = n;
5914 slot = tm_clone_hash->find_slot_with_hash (h, h->hash, INSERT);
5915 *slot = h;
5918 tree
5919 get_tm_clone_pair (tree o)
5921 if (tm_clone_hash)
5923 struct tree_map *h, in;
5925 in.base.from = o;
5926 in.hash = htab_hash_pointer (o);
5927 h = tm_clone_hash->find_with_hash (&in, in.hash);
5928 if (h)
5929 return h->to;
5931 return NULL_TREE;
5934 struct tm_alias_pair
5936 unsigned int uid;
5937 tree from;
5938 tree to;
5942 /* Dump the actual pairs to the .tm_clone_table section. */
5944 static void
5945 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
5947 unsigned i;
5948 tm_alias_pair *p;
5949 bool switched = false;
5951 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
5953 tree src = p->from;
5954 tree dst = p->to;
5955 struct cgraph_node *src_n = cgraph_node::get (src);
5956 struct cgraph_node *dst_n = cgraph_node::get (dst);
5958 /* The function ipa_tm_create_version() marks the clone as needed if
5959 the original function was needed. But we also mark the clone as
5960 needed if we ever called the clone indirectly through
5961 TM_GETTMCLONE. If neither of these are true, we didn't generate
5962 a clone, and we didn't call it indirectly... no sense keeping it
5963 in the clone table. */
5964 if (!dst_n || !dst_n->definition)
5965 continue;
5967 /* This covers the case where we have optimized the original
5968 function away, and only access the transactional clone. */
5969 if (!src_n || !src_n->definition)
5970 continue;
5972 if (!switched)
5974 switch_to_section (targetm.asm_out.tm_clone_table_section ());
5975 assemble_align (POINTER_SIZE);
5976 switched = true;
5979 assemble_integer (XEXP (DECL_RTL (src), 0),
5980 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
5981 assemble_integer (XEXP (DECL_RTL (dst), 0),
5982 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
5986 /* Provide a default for the tm_clone_table section. */
5988 section *
5989 default_clone_table_section (void)
5991 return get_named_section (NULL, ".tm_clone_table", 3);
5994 /* Helper comparison function for qsorting by the DECL_UID stored in
5995 alias_pair->emitted_diags. */
5997 static int
5998 tm_alias_pair_cmp (const void *x, const void *y)
6000 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
6001 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
6002 if (p1->uid < p2->uid)
6003 return -1;
6004 if (p1->uid > p2->uid)
6005 return 1;
6006 return 0;
6009 void
6010 finish_tm_clone_pairs (void)
6012 vec<tm_alias_pair> tm_alias_pairs = vNULL;
6014 if (tm_clone_hash == NULL)
6015 return;
6017 /* We need a determenistic order for the .tm_clone_table, otherwise
6018 we will get bootstrap comparison failures, so dump the hash table
6019 to a vector, sort it, and dump the vector. */
6021 /* Dump the hashtable to a vector. */
6022 tree_map *map;
6023 hash_table<tm_clone_hasher>::iterator iter;
6024 FOR_EACH_HASH_TABLE_ELEMENT (*tm_clone_hash, map, tree_map *, iter)
6026 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
6027 tm_alias_pairs.safe_push (p);
6029 /* Sort it. */
6030 tm_alias_pairs.qsort (tm_alias_pair_cmp);
6032 /* Dump it. */
6033 dump_tm_clone_pairs (tm_alias_pairs);
6035 tm_clone_hash->empty ();
6036 tm_clone_hash = NULL;
6037 tm_alias_pairs.release ();
6041 /* Emit an assembler directive to set symbol for DECL visibility to
6042 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
6044 void
6045 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
6046 int vis ATTRIBUTE_UNUSED)
6048 #ifdef HAVE_GAS_HIDDEN
6049 static const char * const visibility_types[] = {
6050 NULL, "protected", "hidden", "internal"
6053 const char *name, *type;
6054 tree id;
6056 id = DECL_ASSEMBLER_NAME (decl);
6057 ultimate_transparent_alias_target (&id);
6058 name = IDENTIFIER_POINTER (id);
6060 type = visibility_types[vis];
6062 fprintf (asm_out_file, "\t.%s\t", type);
6063 assemble_name (asm_out_file, name);
6064 fprintf (asm_out_file, "\n");
6065 #else
6066 if (!DECL_ARTIFICIAL (decl))
6067 warning (OPT_Wattributes, "visibility attribute not supported "
6068 "in this configuration; ignored");
6069 #endif
6072 /* A helper function to call assemble_visibility when needed for a decl. */
6075 maybe_assemble_visibility (tree decl)
6077 enum symbol_visibility vis = DECL_VISIBILITY (decl);
6079 if (TREE_CODE (decl) == FUNCTION_DECL
6080 && cgraph_node::get (decl)
6081 && cgraph_node::get (decl)->instrumentation_clone
6082 && cgraph_node::get (decl)->instrumented_version)
6083 vis = DECL_VISIBILITY (cgraph_node::get (decl)->instrumented_version->decl);
6085 if (vis != VISIBILITY_DEFAULT)
6087 targetm.asm_out.assemble_visibility (decl, vis);
6088 return 1;
6090 else
6091 return 0;
6094 /* Returns 1 if the target configuration supports defining public symbols
6095 so that one of them will be chosen at link time instead of generating a
6096 multiply-defined symbol error, whether through the use of weak symbols or
6097 a target-specific mechanism for having duplicates discarded. */
6100 supports_one_only (void)
6102 if (SUPPORTS_ONE_ONLY)
6103 return 1;
6104 return TARGET_SUPPORTS_WEAK;
6107 /* Set up DECL as a public symbol that can be defined in multiple
6108 translation units without generating a linker error. */
6110 void
6111 make_decl_one_only (tree decl, tree comdat_group)
6113 struct symtab_node *symbol;
6114 gcc_assert (VAR_OR_FUNCTION_DECL_P (decl));
6116 TREE_PUBLIC (decl) = 1;
6118 if (VAR_P (decl))
6119 symbol = varpool_node::get_create (decl);
6120 else
6121 symbol = cgraph_node::get_create (decl);
6123 if (SUPPORTS_ONE_ONLY)
6125 #ifdef MAKE_DECL_ONE_ONLY
6126 MAKE_DECL_ONE_ONLY (decl);
6127 #endif
6128 symbol->set_comdat_group (comdat_group);
6130 else if (VAR_P (decl)
6131 && (DECL_INITIAL (decl) == 0
6132 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
6133 DECL_COMMON (decl) = 1;
6134 else
6136 gcc_assert (TARGET_SUPPORTS_WEAK);
6137 DECL_WEAK (decl) = 1;
6141 void
6142 init_varasm_once (void)
6144 section_htab = hash_table<section_hasher>::create_ggc (31);
6145 object_block_htab = hash_table<object_block_hasher>::create_ggc (31);
6146 const_desc_htab = hash_table<tree_descriptor_hasher>::create_ggc (1009);
6148 shared_constant_pool = create_constant_pool ();
6150 #ifdef TEXT_SECTION_ASM_OP
6151 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
6152 TEXT_SECTION_ASM_OP);
6153 #endif
6155 #ifdef DATA_SECTION_ASM_OP
6156 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
6157 DATA_SECTION_ASM_OP);
6158 #endif
6160 #ifdef SDATA_SECTION_ASM_OP
6161 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
6162 SDATA_SECTION_ASM_OP);
6163 #endif
6165 #ifdef READONLY_DATA_SECTION_ASM_OP
6166 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
6167 READONLY_DATA_SECTION_ASM_OP);
6168 #endif
6170 #ifdef CTORS_SECTION_ASM_OP
6171 ctors_section = get_unnamed_section (0, output_section_asm_op,
6172 CTORS_SECTION_ASM_OP);
6173 #endif
6175 #ifdef DTORS_SECTION_ASM_OP
6176 dtors_section = get_unnamed_section (0, output_section_asm_op,
6177 DTORS_SECTION_ASM_OP);
6178 #endif
6180 #ifdef BSS_SECTION_ASM_OP
6181 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6182 output_section_asm_op,
6183 BSS_SECTION_ASM_OP);
6184 #endif
6186 #ifdef SBSS_SECTION_ASM_OP
6187 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6188 output_section_asm_op,
6189 SBSS_SECTION_ASM_OP);
6190 #endif
6192 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6193 | SECTION_COMMON, emit_tls_common);
6194 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6195 | SECTION_COMMON, emit_local);
6196 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6197 | SECTION_COMMON, emit_common);
6199 #if defined ASM_OUTPUT_ALIGNED_BSS
6200 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
6201 emit_bss);
6202 #endif
6204 targetm.asm_out.init_sections ();
6206 if (readonly_data_section == NULL)
6207 readonly_data_section = text_section;
6209 #ifdef ASM_OUTPUT_EXTERNAL
6210 pending_assemble_externals_set = new hash_set<tree>;
6211 #endif
6214 enum tls_model
6215 decl_default_tls_model (const_tree decl)
6217 enum tls_model kind;
6218 bool is_local;
6220 is_local = targetm.binds_local_p (decl);
6221 if (!flag_shlib)
6223 if (is_local)
6224 kind = TLS_MODEL_LOCAL_EXEC;
6225 else
6226 kind = TLS_MODEL_INITIAL_EXEC;
6229 /* Local dynamic is inefficient when we're not combining the
6230 parts of the address. */
6231 else if (optimize && is_local)
6232 kind = TLS_MODEL_LOCAL_DYNAMIC;
6233 else
6234 kind = TLS_MODEL_GLOBAL_DYNAMIC;
6235 if (kind < flag_tls_default)
6236 kind = flag_tls_default;
6238 return kind;
6241 /* Select a set of attributes for section NAME based on the properties
6242 of DECL and whether or not RELOC indicates that DECL's initializer
6243 might contain runtime relocations.
6245 We make the section read-only and executable for a function decl,
6246 read-only for a const data decl, and writable for a non-const data decl. */
6248 unsigned int
6249 default_section_type_flags (tree decl, const char *name, int reloc)
6251 unsigned int flags;
6253 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6254 flags = SECTION_CODE;
6255 else if (decl)
6257 enum section_category category
6258 = categorize_decl_for_section (decl, reloc);
6259 if (decl_readonly_section_1 (category))
6260 flags = 0;
6261 else if (category == SECCAT_DATA_REL_RO
6262 || category == SECCAT_DATA_REL_RO_LOCAL)
6263 flags = SECTION_WRITE | SECTION_RELRO;
6264 else
6265 flags = SECTION_WRITE;
6267 else
6269 flags = SECTION_WRITE;
6270 if (strcmp (name, ".data.rel.ro") == 0
6271 || strcmp (name, ".data.rel.ro.local") == 0)
6272 flags |= SECTION_RELRO;
6275 if (decl && DECL_P (decl) && DECL_COMDAT_GROUP (decl))
6276 flags |= SECTION_LINKONCE;
6278 if (strcmp (name, ".vtable_map_vars") == 0)
6279 flags |= SECTION_LINKONCE;
6281 if (decl && VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6282 flags |= SECTION_TLS | SECTION_WRITE;
6284 if (strcmp (name, ".bss") == 0
6285 || strncmp (name, ".bss.", 5) == 0
6286 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6287 || strcmp (name, ".persistent.bss") == 0
6288 || strcmp (name, ".sbss") == 0
6289 || strncmp (name, ".sbss.", 6) == 0
6290 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6291 flags |= SECTION_BSS;
6293 if (strcmp (name, ".tdata") == 0
6294 || strncmp (name, ".tdata.", 7) == 0
6295 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6296 flags |= SECTION_TLS;
6298 if (strcmp (name, ".tbss") == 0
6299 || strncmp (name, ".tbss.", 6) == 0
6300 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6301 flags |= SECTION_TLS | SECTION_BSS;
6303 /* These three sections have special ELF types. They are neither
6304 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
6305 want to print a section type (@progbits or @nobits). If someone
6306 is silly enough to emit code or TLS variables to one of these
6307 sections, then don't handle them specially. */
6308 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6309 && (strcmp (name, ".init_array") == 0
6310 || strcmp (name, ".fini_array") == 0
6311 || strcmp (name, ".preinit_array") == 0))
6312 flags |= SECTION_NOTYPE;
6314 return flags;
6317 /* Return true if the target supports some form of global BSS,
6318 either through bss_noswitch_section, or by selecting a BSS
6319 section in TARGET_ASM_SELECT_SECTION. */
6321 bool
6322 have_global_bss_p (void)
6324 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6327 /* Output assembly to switch to section NAME with attribute FLAGS.
6328 Four variants for common object file formats. */
6330 void
6331 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6332 unsigned int flags ATTRIBUTE_UNUSED,
6333 tree decl ATTRIBUTE_UNUSED)
6335 /* Some object formats don't support named sections at all. The
6336 front-end should already have flagged this as an error. */
6337 gcc_unreachable ();
6340 #ifndef TLS_SECTION_ASM_FLAG
6341 #define TLS_SECTION_ASM_FLAG 'T'
6342 #endif
6344 void
6345 default_elf_asm_named_section (const char *name, unsigned int flags,
6346 tree decl)
6348 char flagchars[11], *f = flagchars;
6349 unsigned int numeric_value = 0;
6351 /* If we have already declared this section, we can use an
6352 abbreviated form to switch back to it -- unless this section is
6353 part of a COMDAT groups, in which case GAS requires the full
6354 declaration every time. */
6355 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6356 && (flags & SECTION_DECLARED))
6358 fprintf (asm_out_file, "\t.section\t%s\n", name);
6359 return;
6362 /* If we have a machine specific flag, then use the numeric value to pass
6363 this on to GAS. */
6364 if (targetm.asm_out.elf_flags_numeric (flags, &numeric_value))
6365 snprintf (f, sizeof (flagchars), "0x%08x", numeric_value);
6366 else
6368 if (!(flags & SECTION_DEBUG))
6369 *f++ = 'a';
6370 #if defined (HAVE_GAS_SECTION_EXCLUDE) && HAVE_GAS_SECTION_EXCLUDE == 1
6371 if (flags & SECTION_EXCLUDE)
6372 *f++ = 'e';
6373 #endif
6374 if (flags & SECTION_WRITE)
6375 *f++ = 'w';
6376 if (flags & SECTION_CODE)
6377 *f++ = 'x';
6378 if (flags & SECTION_SMALL)
6379 *f++ = 's';
6380 if (flags & SECTION_MERGE)
6381 *f++ = 'M';
6382 if (flags & SECTION_STRINGS)
6383 *f++ = 'S';
6384 if (flags & SECTION_TLS)
6385 *f++ = TLS_SECTION_ASM_FLAG;
6386 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6387 *f++ = 'G';
6388 #ifdef MACH_DEP_SECTION_ASM_FLAG
6389 if (flags & SECTION_MACH_DEP)
6390 *f++ = MACH_DEP_SECTION_ASM_FLAG;
6391 #endif
6392 *f = '\0';
6395 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6397 if (!(flags & SECTION_NOTYPE))
6399 const char *type;
6400 const char *format;
6402 if (flags & SECTION_BSS)
6403 type = "nobits";
6404 else
6405 type = "progbits";
6407 format = ",@%s";
6408 /* On platforms that use "@" as the assembly comment character,
6409 use "%" instead. */
6410 if (strcmp (ASM_COMMENT_START, "@") == 0)
6411 format = ",%%%s";
6412 fprintf (asm_out_file, format, type);
6414 if (flags & SECTION_ENTSIZE)
6415 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6416 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6418 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6419 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6420 else
6421 fprintf (asm_out_file, ",%s,comdat",
6422 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6426 putc ('\n', asm_out_file);
6429 void
6430 default_coff_asm_named_section (const char *name, unsigned int flags,
6431 tree decl ATTRIBUTE_UNUSED)
6433 char flagchars[8], *f = flagchars;
6435 if (flags & SECTION_WRITE)
6436 *f++ = 'w';
6437 if (flags & SECTION_CODE)
6438 *f++ = 'x';
6439 *f = '\0';
6441 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6444 void
6445 default_pe_asm_named_section (const char *name, unsigned int flags,
6446 tree decl)
6448 default_coff_asm_named_section (name, flags, decl);
6450 if (flags & SECTION_LINKONCE)
6452 /* Functions may have been compiled at various levels of
6453 optimization so we can't use `same_size' here.
6454 Instead, have the linker pick one. */
6455 fprintf (asm_out_file, "\t.linkonce %s\n",
6456 (flags & SECTION_CODE ? "discard" : "same_size"));
6460 /* The lame default section selector. */
6462 section *
6463 default_select_section (tree decl, int reloc,
6464 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6466 if (DECL_P (decl))
6468 if (decl_readonly_section (decl, reloc))
6469 return readonly_data_section;
6471 else if (TREE_CODE (decl) == CONSTRUCTOR)
6473 if (! ((flag_pic && reloc)
6474 || !TREE_READONLY (decl)
6475 || TREE_SIDE_EFFECTS (decl)
6476 || !TREE_CONSTANT (decl)))
6477 return readonly_data_section;
6479 else if (TREE_CODE (decl) == STRING_CST)
6480 return readonly_data_section;
6481 else if (! (flag_pic && reloc))
6482 return readonly_data_section;
6484 return data_section;
6487 enum section_category
6488 categorize_decl_for_section (const_tree decl, int reloc)
6490 enum section_category ret;
6492 if (TREE_CODE (decl) == FUNCTION_DECL)
6493 return SECCAT_TEXT;
6494 else if (TREE_CODE (decl) == STRING_CST)
6496 if ((flag_sanitize & SANITIZE_ADDRESS)
6497 && asan_protect_global (CONST_CAST_TREE (decl)))
6498 /* or !flag_merge_constants */
6499 return SECCAT_RODATA;
6500 else
6501 return SECCAT_RODATA_MERGE_STR;
6503 else if (VAR_P (decl))
6505 if (bss_initializer_p (decl))
6506 ret = SECCAT_BSS;
6507 else if (! TREE_READONLY (decl)
6508 || TREE_SIDE_EFFECTS (decl)
6509 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
6511 /* Here the reloc_rw_mask is not testing whether the section should
6512 be read-only or not, but whether the dynamic link will have to
6513 do something. If so, we wish to segregate the data in order to
6514 minimize cache misses inside the dynamic linker. */
6515 if (reloc & targetm.asm_out.reloc_rw_mask ())
6516 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6517 else
6518 ret = SECCAT_DATA;
6520 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6521 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6522 else if (reloc || flag_merge_constants < 2
6523 || ((flag_sanitize & SANITIZE_ADDRESS)
6524 && asan_protect_global (CONST_CAST_TREE (decl))))
6525 /* C and C++ don't allow different variables to share the same
6526 location. -fmerge-all-constants allows even that (at the
6527 expense of not conforming). */
6528 ret = SECCAT_RODATA;
6529 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6530 ret = SECCAT_RODATA_MERGE_STR_INIT;
6531 else
6532 ret = SECCAT_RODATA_MERGE_CONST;
6534 else if (TREE_CODE (decl) == CONSTRUCTOR)
6536 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6537 || TREE_SIDE_EFFECTS (decl)
6538 || ! TREE_CONSTANT (decl))
6539 ret = SECCAT_DATA;
6540 else
6541 ret = SECCAT_RODATA;
6543 else
6544 ret = SECCAT_RODATA;
6546 /* There are no read-only thread-local sections. */
6547 if (VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6549 /* Note that this would be *just* SECCAT_BSS, except that there's
6550 no concept of a read-only thread-local-data section. */
6551 if (ret == SECCAT_BSS
6552 || (flag_zero_initialized_in_bss
6553 && initializer_zerop (DECL_INITIAL (decl))))
6554 ret = SECCAT_TBSS;
6555 else
6556 ret = SECCAT_TDATA;
6559 /* If the target uses small data sections, select it. */
6560 else if (targetm.in_small_data_p (decl))
6562 if (ret == SECCAT_BSS)
6563 ret = SECCAT_SBSS;
6564 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6565 ret = SECCAT_SRODATA;
6566 else
6567 ret = SECCAT_SDATA;
6570 return ret;
6573 static bool
6574 decl_readonly_section_1 (enum section_category category)
6576 switch (category)
6578 case SECCAT_RODATA:
6579 case SECCAT_RODATA_MERGE_STR:
6580 case SECCAT_RODATA_MERGE_STR_INIT:
6581 case SECCAT_RODATA_MERGE_CONST:
6582 case SECCAT_SRODATA:
6583 return true;
6584 default:
6585 return false;
6589 bool
6590 decl_readonly_section (const_tree decl, int reloc)
6592 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6595 /* Select a section based on the above categorization. */
6597 section *
6598 default_elf_select_section (tree decl, int reloc,
6599 unsigned HOST_WIDE_INT align)
6601 const char *sname;
6602 switch (categorize_decl_for_section (decl, reloc))
6604 case SECCAT_TEXT:
6605 /* We're not supposed to be called on FUNCTION_DECLs. */
6606 gcc_unreachable ();
6607 case SECCAT_RODATA:
6608 return readonly_data_section;
6609 case SECCAT_RODATA_MERGE_STR:
6610 return mergeable_string_section (decl, align, 0);
6611 case SECCAT_RODATA_MERGE_STR_INIT:
6612 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6613 case SECCAT_RODATA_MERGE_CONST:
6614 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6615 case SECCAT_SRODATA:
6616 sname = ".sdata2";
6617 break;
6618 case SECCAT_DATA:
6619 return data_section;
6620 case SECCAT_DATA_REL:
6621 sname = ".data.rel";
6622 break;
6623 case SECCAT_DATA_REL_LOCAL:
6624 sname = ".data.rel.local";
6625 break;
6626 case SECCAT_DATA_REL_RO:
6627 sname = ".data.rel.ro";
6628 break;
6629 case SECCAT_DATA_REL_RO_LOCAL:
6630 sname = ".data.rel.ro.local";
6631 break;
6632 case SECCAT_SDATA:
6633 sname = ".sdata";
6634 break;
6635 case SECCAT_TDATA:
6636 sname = ".tdata";
6637 break;
6638 case SECCAT_BSS:
6639 if (bss_section)
6640 return bss_section;
6641 sname = ".bss";
6642 break;
6643 case SECCAT_SBSS:
6644 sname = ".sbss";
6645 break;
6646 case SECCAT_TBSS:
6647 sname = ".tbss";
6648 break;
6649 default:
6650 gcc_unreachable ();
6653 return get_named_section (decl, sname, reloc);
6656 /* Construct a unique section name based on the decl name and the
6657 categorization performed above. */
6659 void
6660 default_unique_section (tree decl, int reloc)
6662 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6663 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6664 const char *prefix, *name, *linkonce;
6665 char *string;
6666 tree id;
6668 switch (categorize_decl_for_section (decl, reloc))
6670 case SECCAT_TEXT:
6671 prefix = one_only ? ".t" : ".text";
6672 break;
6673 case SECCAT_RODATA:
6674 case SECCAT_RODATA_MERGE_STR:
6675 case SECCAT_RODATA_MERGE_STR_INIT:
6676 case SECCAT_RODATA_MERGE_CONST:
6677 prefix = one_only ? ".r" : ".rodata";
6678 break;
6679 case SECCAT_SRODATA:
6680 prefix = one_only ? ".s2" : ".sdata2";
6681 break;
6682 case SECCAT_DATA:
6683 prefix = one_only ? ".d" : ".data";
6684 break;
6685 case SECCAT_DATA_REL:
6686 prefix = one_only ? ".d.rel" : ".data.rel";
6687 break;
6688 case SECCAT_DATA_REL_LOCAL:
6689 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6690 break;
6691 case SECCAT_DATA_REL_RO:
6692 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6693 break;
6694 case SECCAT_DATA_REL_RO_LOCAL:
6695 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6696 break;
6697 case SECCAT_SDATA:
6698 prefix = one_only ? ".s" : ".sdata";
6699 break;
6700 case SECCAT_BSS:
6701 prefix = one_only ? ".b" : ".bss";
6702 break;
6703 case SECCAT_SBSS:
6704 prefix = one_only ? ".sb" : ".sbss";
6705 break;
6706 case SECCAT_TDATA:
6707 prefix = one_only ? ".td" : ".tdata";
6708 break;
6709 case SECCAT_TBSS:
6710 prefix = one_only ? ".tb" : ".tbss";
6711 break;
6712 default:
6713 gcc_unreachable ();
6716 id = DECL_ASSEMBLER_NAME (decl);
6717 ultimate_transparent_alias_target (&id);
6718 name = IDENTIFIER_POINTER (id);
6719 name = targetm.strip_name_encoding (name);
6721 /* If we're using one_only, then there needs to be a .gnu.linkonce
6722 prefix to the section name. */
6723 linkonce = one_only ? ".gnu.linkonce" : "";
6725 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6727 set_decl_section_name (decl, string);
6730 /* Subroutine of compute_reloc_for_rtx for leaf rtxes. */
6732 static int
6733 compute_reloc_for_rtx_1 (const_rtx x)
6735 switch (GET_CODE (x))
6737 case SYMBOL_REF:
6738 return SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6739 case LABEL_REF:
6740 return 1;
6741 default:
6742 return 0;
6746 /* Like compute_reloc_for_constant, except for an RTX. The return value
6747 is a mask for which bit 1 indicates a global relocation, and bit 0
6748 indicates a local relocation. */
6750 static int
6751 compute_reloc_for_rtx (const_rtx x)
6753 switch (GET_CODE (x))
6755 case SYMBOL_REF:
6756 case LABEL_REF:
6757 return compute_reloc_for_rtx_1 (x);
6759 case CONST:
6761 int reloc = 0;
6762 subrtx_iterator::array_type array;
6763 FOR_EACH_SUBRTX (iter, array, x, ALL)
6764 reloc |= compute_reloc_for_rtx_1 (*iter);
6765 return reloc;
6768 default:
6769 return 0;
6773 section *
6774 default_select_rtx_section (machine_mode mode ATTRIBUTE_UNUSED,
6775 rtx x,
6776 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6778 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6779 return data_section;
6780 else
6781 return readonly_data_section;
6784 section *
6785 default_elf_select_rtx_section (machine_mode mode, rtx x,
6786 unsigned HOST_WIDE_INT align)
6788 int reloc = compute_reloc_for_rtx (x);
6790 /* ??? Handle small data here somehow. */
6792 if (reloc & targetm.asm_out.reloc_rw_mask ())
6794 if (reloc == 1)
6795 return get_named_section (NULL, ".data.rel.ro.local", 1);
6796 else
6797 return get_named_section (NULL, ".data.rel.ro", 3);
6800 return mergeable_constant_section (mode, align, 0);
6803 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6805 void
6806 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6808 rtx symbol;
6809 int flags;
6811 /* Careful not to prod global register variables. */
6812 if (!MEM_P (rtl))
6813 return;
6814 symbol = XEXP (rtl, 0);
6815 if (GET_CODE (symbol) != SYMBOL_REF)
6816 return;
6818 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6819 if (TREE_CODE (decl) == FUNCTION_DECL)
6820 flags |= SYMBOL_FLAG_FUNCTION;
6821 if (targetm.binds_local_p (decl))
6822 flags |= SYMBOL_FLAG_LOCAL;
6823 if (VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6824 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6825 else if (targetm.in_small_data_p (decl))
6826 flags |= SYMBOL_FLAG_SMALL;
6827 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6828 being PUBLIC, the thing *must* be defined in this translation unit.
6829 Prevent this buglet from being propagated into rtl code as well. */
6830 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6831 flags |= SYMBOL_FLAG_EXTERNAL;
6833 SYMBOL_REF_FLAGS (symbol) = flags;
6836 /* By default, we do nothing for encode_section_info, so we need not
6837 do anything but discard the '*' marker. */
6839 const char *
6840 default_strip_name_encoding (const char *str)
6842 return str + (*str == '*');
6845 #ifdef ASM_OUTPUT_DEF
6846 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6847 anchor relative to ".", the current section position. */
6849 void
6850 default_asm_output_anchor (rtx symbol)
6852 char buffer[100];
6854 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6855 SYMBOL_REF_BLOCK_OFFSET (symbol));
6856 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6858 #endif
6860 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6862 bool
6863 default_use_anchors_for_symbol_p (const_rtx symbol)
6865 section *sect;
6866 tree decl;
6868 /* Don't use anchors for mergeable sections. The linker might move
6869 the objects around. */
6870 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6871 if (sect->common.flags & SECTION_MERGE)
6872 return false;
6874 /* Don't use anchors for small data sections. The small data register
6875 acts as an anchor for such sections. */
6876 if (sect->common.flags & SECTION_SMALL)
6877 return false;
6879 decl = SYMBOL_REF_DECL (symbol);
6880 if (decl && DECL_P (decl))
6882 /* Don't use section anchors for decls that might be defined or
6883 usurped by other modules. */
6884 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6885 return false;
6887 /* Don't use section anchors for decls that will be placed in a
6888 small data section. */
6889 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6890 one above. The problem is that we only use SECTION_SMALL for
6891 sections that should be marked as small in the section directive. */
6892 if (targetm.in_small_data_p (decl))
6893 return false;
6895 /* Don't use section anchors for decls that won't fit inside a single
6896 anchor range to reduce the amount of instructions required to refer
6897 to the entire declaration. */
6898 if (DECL_SIZE_UNIT (decl) == NULL_TREE
6899 || !tree_fits_uhwi_p (DECL_SIZE_UNIT (decl))
6900 || (tree_to_uhwi (DECL_SIZE_UNIT (decl))
6901 >= (unsigned HOST_WIDE_INT) targetm.max_anchor_offset))
6902 return false;
6905 return true;
6908 /* Return true when RESOLUTION indicate that symbol will be bound to the
6909 definition provided by current .o file. */
6911 static bool
6912 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
6914 return (resolution == LDPR_PREVAILING_DEF
6915 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6916 || resolution == LDPR_PREVAILING_DEF_IRONLY);
6919 /* Return true when RESOLUTION indicate that symbol will be bound locally
6920 within current executable or DSO. */
6922 static bool
6923 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
6925 return (resolution == LDPR_PREVAILING_DEF
6926 || resolution == LDPR_PREVAILING_DEF_IRONLY
6927 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6928 || resolution == LDPR_PREEMPTED_REG
6929 || resolution == LDPR_PREEMPTED_IR
6930 || resolution == LDPR_RESOLVED_IR
6931 || resolution == LDPR_RESOLVED_EXEC);
6934 /* COMMON_LOCAL_P is true means that the linker can guarantee that an
6935 uninitialized common symbol in the executable will still be defined
6936 (through COPY relocation) in the executable. */
6938 bool
6939 default_binds_local_p_3 (const_tree exp, bool shlib, bool weak_dominate,
6940 bool extern_protected_data, bool common_local_p)
6942 /* A non-decl is an entry in the constant pool. */
6943 if (!DECL_P (exp))
6944 return true;
6946 /* Weakrefs may not bind locally, even though the weakref itself is always
6947 static and therefore local. Similarly, the resolver for ifunc functions
6948 might resolve to a non-local function.
6949 FIXME: We can resolve the weakref case more curefuly by looking at the
6950 weakref alias. */
6951 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
6952 || (TREE_CODE (exp) == FUNCTION_DECL
6953 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
6954 return false;
6956 /* Static variables are always local. */
6957 if (! TREE_PUBLIC (exp))
6958 return true;
6960 /* With resolution file in hand, take look into resolutions.
6961 We can't just return true for resolved_locally symbols,
6962 because dynamic linking might overwrite symbols
6963 in shared libraries. */
6964 bool resolved_locally = false;
6966 bool uninited_common = (DECL_COMMON (exp)
6967 && (DECL_INITIAL (exp) == NULL
6968 || (!in_lto_p
6969 && DECL_INITIAL (exp) == error_mark_node)));
6971 /* A non-external variable is defined locally only if it isn't
6972 uninitialized COMMON variable or common_local_p is true. */
6973 bool defined_locally = (!DECL_EXTERNAL (exp)
6974 && (!uninited_common || common_local_p));
6975 if (symtab_node *node = symtab_node::get (exp))
6977 if (node->in_other_partition)
6978 defined_locally = true;
6979 if (node->can_be_discarded_p ())
6981 else if (resolution_to_local_definition_p (node->resolution))
6982 defined_locally = resolved_locally = true;
6983 else if (resolution_local_p (node->resolution))
6984 resolved_locally = true;
6986 if (defined_locally && weak_dominate && !shlib)
6987 resolved_locally = true;
6989 /* Undefined weak symbols are never defined locally. */
6990 if (DECL_WEAK (exp) && !defined_locally)
6991 return false;
6993 /* A symbol is local if the user has said explicitly that it will be,
6994 or if we have a definition for the symbol. We cannot infer visibility
6995 for undefined symbols. */
6996 if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT
6997 && (TREE_CODE (exp) == FUNCTION_DECL
6998 || !extern_protected_data
6999 || DECL_VISIBILITY (exp) != VISIBILITY_PROTECTED)
7000 && (DECL_VISIBILITY_SPECIFIED (exp) || defined_locally))
7001 return true;
7003 /* If PIC, then assume that any global name can be overridden by
7004 symbols resolved from other modules. */
7005 if (shlib)
7006 return false;
7008 /* Variables defined outside this object might not be local. */
7009 if (DECL_EXTERNAL (exp) && !resolved_locally)
7010 return false;
7012 /* Non-dominant weak symbols are not defined locally. */
7013 if (DECL_WEAK (exp) && !resolved_locally)
7014 return false;
7016 /* Uninitialized COMMON variable may be unified with symbols
7017 resolved from other modules. */
7018 if (uninited_common && !resolved_locally)
7019 return false;
7021 /* Otherwise we're left with initialized (or non-common) global data
7022 which is of necessity defined locally. */
7023 return true;
7026 /* Assume ELF-ish defaults, since that's pretty much the most liberal
7027 wrt cross-module name binding. */
7029 bool
7030 default_binds_local_p (const_tree exp)
7032 return default_binds_local_p_3 (exp, flag_shlib != 0, true, false, false);
7035 /* Similar to default_binds_local_p, but common symbol may be local and
7036 extern protected data is non-local. */
7038 bool
7039 default_binds_local_p_2 (const_tree exp)
7041 return default_binds_local_p_3 (exp, flag_shlib != 0, true, true,
7042 !flag_pic);
7045 bool
7046 default_binds_local_p_1 (const_tree exp, int shlib)
7048 return default_binds_local_p_3 (exp, shlib != 0, false, false, false);
7051 /* Return true when references to DECL must bind to current definition in
7052 final executable.
7054 The condition is usually equivalent to whether the function binds to the
7055 current module (shared library or executable), that is to binds_local_p.
7056 We use this fact to avoid need for another target hook and implement
7057 the logic using binds_local_p and just special cases where
7058 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
7059 the weak definitions (that can be overwritten at linktime by other
7060 definition from different object file) and when resolution info is available
7061 we simply use the knowledge passed to us by linker plugin. */
7062 bool
7063 decl_binds_to_current_def_p (const_tree decl)
7065 gcc_assert (DECL_P (decl));
7066 if (!targetm.binds_local_p (decl))
7067 return false;
7068 if (!TREE_PUBLIC (decl))
7069 return true;
7071 /* When resolution is available, just use it. */
7072 if (symtab_node *node = symtab_node::get (decl))
7074 if (node->resolution != LDPR_UNKNOWN
7075 && !node->can_be_discarded_p ())
7076 return resolution_to_local_definition_p (node->resolution);
7079 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
7080 binds locally but still can be overwritten), DECL_COMMON (can be merged
7081 with a non-common definition somewhere in the same module) or
7082 DECL_EXTERNAL.
7083 This rely on fact that binds_local_p behave as decl_replaceable_p
7084 for all other declaration types. */
7085 if (DECL_WEAK (decl))
7086 return false;
7087 if (DECL_COMMON (decl)
7088 && (DECL_INITIAL (decl) == NULL
7089 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
7090 return false;
7091 if (DECL_EXTERNAL (decl))
7092 return false;
7093 return true;
7096 /* A replaceable function or variable is one which may be replaced
7097 at link-time with an entirely different definition, provided that the
7098 replacement has the same type. For example, functions declared
7099 with __attribute__((weak)) on most systems are replaceable.
7101 COMDAT functions are not replaceable, since all definitions of the
7102 function must be equivalent. It is important that COMDAT functions
7103 not be treated as replaceable so that use of C++ template
7104 instantiations is not penalized. */
7106 bool
7107 decl_replaceable_p (tree decl)
7109 gcc_assert (DECL_P (decl));
7110 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
7111 return false;
7112 if (!flag_semantic_interposition
7113 && !DECL_WEAK (decl))
7114 return false;
7115 return !decl_binds_to_current_def_p (decl);
7118 /* Default function to output code that will globalize a label. A
7119 target must define GLOBAL_ASM_OP or provide its own function to
7120 globalize a label. */
7121 #ifdef GLOBAL_ASM_OP
7122 void
7123 default_globalize_label (FILE * stream, const char *name)
7125 fputs (GLOBAL_ASM_OP, stream);
7126 assemble_name (stream, name);
7127 putc ('\n', stream);
7129 #endif /* GLOBAL_ASM_OP */
7131 /* Default function to output code that will globalize a declaration. */
7132 void
7133 default_globalize_decl_name (FILE * stream, tree decl)
7135 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
7136 targetm.asm_out.globalize_label (stream, name);
7139 /* Default function to output a label for unwind information. The
7140 default is to do nothing. A target that needs nonlocal labels for
7141 unwind information must provide its own function to do this. */
7142 void
7143 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
7144 tree decl ATTRIBUTE_UNUSED,
7145 int for_eh ATTRIBUTE_UNUSED,
7146 int empty ATTRIBUTE_UNUSED)
7150 /* Default function to output a label to divide up the exception table.
7151 The default is to do nothing. A target that needs/wants to divide
7152 up the table must provide it's own function to do this. */
7153 void
7154 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
7158 /* This is how to output an internal numbered label where PREFIX is
7159 the class of label and LABELNO is the number within the class. */
7161 void
7162 default_generate_internal_label (char *buf, const char *prefix,
7163 unsigned long labelno)
7165 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
7168 /* This is how to output an internal numbered label where PREFIX is
7169 the class of label and LABELNO is the number within the class. */
7171 void
7172 default_internal_label (FILE *stream, const char *prefix,
7173 unsigned long labelno)
7175 char *const buf = (char *) alloca (40 + strlen (prefix));
7176 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
7177 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
7181 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
7183 void
7184 default_asm_declare_constant_name (FILE *file, const char *name,
7185 const_tree exp ATTRIBUTE_UNUSED,
7186 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
7188 assemble_label (file, name);
7191 /* This is the default behavior at the beginning of a file. It's
7192 controlled by two other target-hook toggles. */
7193 void
7194 default_file_start (void)
7196 if (targetm.asm_file_start_app_off
7197 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
7198 fputs (ASM_APP_OFF, asm_out_file);
7200 if (targetm.asm_file_start_file_directive)
7202 /* LTO produced units have no meaningful main_input_filename. */
7203 if (in_lto_p)
7204 output_file_directive (asm_out_file, "<artificial>");
7205 else
7206 output_file_directive (asm_out_file, main_input_filename);
7210 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
7211 which emits a special section directive used to indicate whether or
7212 not this object file needs an executable stack. This is primarily
7213 a GNU extension to ELF but could be used on other targets. */
7215 int trampolines_created;
7217 void
7218 file_end_indicate_exec_stack (void)
7220 unsigned int flags = SECTION_DEBUG;
7221 if (trampolines_created)
7222 flags |= SECTION_CODE;
7224 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
7227 /* Emit a special section directive to indicate that this object file
7228 was compiled with -fsplit-stack. This is used to let the linker
7229 detect calls between split-stack code and non-split-stack code, so
7230 that it can modify the split-stack code to allocate a sufficiently
7231 large stack. We emit another special section if there are any
7232 functions in this file which have the no_split_stack attribute, to
7233 prevent the linker from warning about being unable to convert the
7234 functions if they call non-split-stack code. */
7236 void
7237 file_end_indicate_split_stack (void)
7239 if (flag_split_stack)
7241 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
7242 NULL));
7243 if (saw_no_split_stack)
7244 switch_to_section (get_section (".note.GNU-no-split-stack",
7245 SECTION_DEBUG, NULL));
7249 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
7250 a get_unnamed_section callback. */
7252 void
7253 output_section_asm_op (const void *directive)
7255 fprintf (asm_out_file, "%s\n", (const char *) directive);
7258 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
7259 the current section is NEW_SECTION. */
7261 void
7262 switch_to_section (section *new_section)
7264 if (in_section == new_section)
7265 return;
7267 if (new_section->common.flags & SECTION_FORGET)
7268 in_section = NULL;
7269 else
7270 in_section = new_section;
7272 switch (SECTION_STYLE (new_section))
7274 case SECTION_NAMED:
7275 targetm.asm_out.named_section (new_section->named.name,
7276 new_section->named.common.flags,
7277 new_section->named.decl);
7278 break;
7280 case SECTION_UNNAMED:
7281 new_section->unnamed.callback (new_section->unnamed.data);
7282 break;
7284 case SECTION_NOSWITCH:
7285 gcc_unreachable ();
7286 break;
7289 new_section->common.flags |= SECTION_DECLARED;
7292 /* If block symbol SYMBOL has not yet been assigned an offset, place
7293 it at the end of its block. */
7295 void
7296 place_block_symbol (rtx symbol)
7298 unsigned HOST_WIDE_INT size, mask, offset;
7299 struct constant_descriptor_rtx *desc;
7300 unsigned int alignment;
7301 struct object_block *block;
7302 tree decl;
7304 gcc_assert (SYMBOL_REF_BLOCK (symbol));
7305 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7306 return;
7308 /* Work out the symbol's size and alignment. */
7309 if (CONSTANT_POOL_ADDRESS_P (symbol))
7311 desc = SYMBOL_REF_CONSTANT (symbol);
7312 alignment = desc->align;
7313 size = GET_MODE_SIZE (desc->mode);
7315 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7317 decl = SYMBOL_REF_DECL (symbol);
7318 gcc_checking_assert (DECL_IN_CONSTANT_POOL (decl));
7319 alignment = DECL_ALIGN (decl);
7320 size = get_constant_size (DECL_INITIAL (decl));
7321 if ((flag_sanitize & SANITIZE_ADDRESS)
7322 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7323 && asan_protect_global (DECL_INITIAL (decl)))
7325 size += asan_red_zone_size (size);
7326 alignment = MAX (alignment,
7327 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7330 else
7332 struct symtab_node *snode;
7333 decl = SYMBOL_REF_DECL (symbol);
7335 snode = symtab_node::get (decl);
7336 if (snode->alias)
7338 rtx target = DECL_RTL (snode->ultimate_alias_target ()->decl);
7340 gcc_assert (MEM_P (target)
7341 && GET_CODE (XEXP (target, 0)) == SYMBOL_REF
7342 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (target, 0)));
7343 target = XEXP (target, 0);
7344 place_block_symbol (target);
7345 SYMBOL_REF_BLOCK_OFFSET (symbol) = SYMBOL_REF_BLOCK_OFFSET (target);
7346 return;
7348 alignment = get_variable_align (decl);
7349 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7350 if ((flag_sanitize & SANITIZE_ADDRESS)
7351 && asan_protect_global (decl))
7353 size += asan_red_zone_size (size);
7354 alignment = MAX (alignment,
7355 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7359 /* Calculate the object's offset from the start of the block. */
7360 block = SYMBOL_REF_BLOCK (symbol);
7361 mask = alignment / BITS_PER_UNIT - 1;
7362 offset = (block->size + mask) & ~mask;
7363 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7365 /* Record the block's new alignment and size. */
7366 block->alignment = MAX (block->alignment, alignment);
7367 block->size = offset + size;
7369 vec_safe_push (block->objects, symbol);
7372 /* Return the anchor that should be used to address byte offset OFFSET
7373 from the first object in BLOCK. MODEL is the TLS model used
7374 to access it. */
7377 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7378 enum tls_model model)
7380 char label[100];
7381 unsigned int begin, middle, end;
7382 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7383 rtx anchor;
7385 /* Work out the anchor's offset. Use an offset of 0 for the first
7386 anchor so that we don't pessimize the case where we take the address
7387 of a variable at the beginning of the block. This is particularly
7388 useful when a block has only one variable assigned to it.
7390 We try to place anchors RANGE bytes apart, so there can then be
7391 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7392 a ptr_mode offset. With some target settings, the lowest such
7393 anchor might be out of range for the lowest ptr_mode offset;
7394 likewise the highest anchor for the highest offset. Use anchors
7395 at the extreme ends of the ptr_mode range in such cases.
7397 All arithmetic uses unsigned integers in order to avoid
7398 signed overflow. */
7399 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7400 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7401 range = max_offset - min_offset + 1;
7402 if (range == 0)
7403 offset = 0;
7404 else
7406 bias = HOST_WIDE_INT_1U << (GET_MODE_BITSIZE (ptr_mode) - 1);
7407 if (offset < 0)
7409 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7410 delta -= delta % range;
7411 if (delta > bias)
7412 delta = bias;
7413 offset = (HOST_WIDE_INT) (-delta);
7415 else
7417 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7418 delta -= delta % range;
7419 if (delta > bias - 1)
7420 delta = bias - 1;
7421 offset = (HOST_WIDE_INT) delta;
7425 /* Do a binary search to see if there's already an anchor we can use.
7426 Set BEGIN to the new anchor's index if not. */
7427 begin = 0;
7428 end = vec_safe_length (block->anchors);
7429 while (begin != end)
7431 middle = (end + begin) / 2;
7432 anchor = (*block->anchors)[middle];
7433 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7434 end = middle;
7435 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7436 begin = middle + 1;
7437 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7438 end = middle;
7439 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7440 begin = middle + 1;
7441 else
7442 return anchor;
7445 /* Create a new anchor with a unique label. */
7446 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7447 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7448 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7449 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7451 /* Insert it at index BEGIN. */
7452 vec_safe_insert (block->anchors, begin, anchor);
7453 return anchor;
7456 /* Output the objects in BLOCK. */
7458 static void
7459 output_object_block (struct object_block *block)
7461 struct constant_descriptor_rtx *desc;
7462 unsigned int i;
7463 HOST_WIDE_INT offset;
7464 tree decl;
7465 rtx symbol;
7467 if (!block->objects)
7468 return;
7470 /* Switch to the section and make sure that the first byte is
7471 suitably aligned. */
7472 /* Special case VTV comdat sections similar to assemble_variable. */
7473 if (SECTION_STYLE (block->sect) == SECTION_NAMED
7474 && block->sect->named.name
7475 && (strcmp (block->sect->named.name, ".vtable_map_vars") == 0))
7476 handle_vtv_comdat_section (block->sect, block->sect->named.decl);
7477 else
7478 switch_to_section (block->sect);
7480 assemble_align (block->alignment);
7482 /* Define the values of all anchors relative to the current section
7483 position. */
7484 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7485 targetm.asm_out.output_anchor (symbol);
7487 /* Output the objects themselves. */
7488 offset = 0;
7489 FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7491 /* Move to the object's offset, padding with zeros if necessary. */
7492 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7493 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7494 if (CONSTANT_POOL_ADDRESS_P (symbol))
7496 desc = SYMBOL_REF_CONSTANT (symbol);
7497 /* Pass 1 for align as we have already laid out everything in the block.
7498 So aligning shouldn't be necessary. */
7499 output_constant_pool_1 (desc, 1);
7500 offset += GET_MODE_SIZE (desc->mode);
7502 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7504 HOST_WIDE_INT size;
7505 decl = SYMBOL_REF_DECL (symbol);
7506 assemble_constant_contents
7507 (DECL_INITIAL (decl), XSTR (symbol, 0), DECL_ALIGN (decl));
7509 size = get_constant_size (DECL_INITIAL (decl));
7510 offset += size;
7511 if ((flag_sanitize & SANITIZE_ADDRESS)
7512 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7513 && asan_protect_global (DECL_INITIAL (decl)))
7515 size = asan_red_zone_size (size);
7516 assemble_zeros (size);
7517 offset += size;
7520 else
7522 HOST_WIDE_INT size;
7523 decl = SYMBOL_REF_DECL (symbol);
7524 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7525 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7526 offset += size;
7527 if ((flag_sanitize & SANITIZE_ADDRESS)
7528 && asan_protect_global (decl))
7530 size = asan_red_zone_size (size);
7531 assemble_zeros (size);
7532 offset += size;
7538 /* A callback for qsort to compare object_blocks. */
7540 static int
7541 output_object_block_compare (const void *x, const void *y)
7543 object_block *p1 = *(object_block * const*)x;
7544 object_block *p2 = *(object_block * const*)y;
7546 if (p1->sect->common.flags & SECTION_NAMED
7547 && !(p2->sect->common.flags & SECTION_NAMED))
7548 return 1;
7550 if (!(p1->sect->common.flags & SECTION_NAMED)
7551 && p2->sect->common.flags & SECTION_NAMED)
7552 return -1;
7554 if (p1->sect->common.flags & SECTION_NAMED
7555 && p2->sect->common.flags & SECTION_NAMED)
7556 return strcmp (p1->sect->named.name, p2->sect->named.name);
7558 unsigned f1 = p1->sect->common.flags;
7559 unsigned f2 = p2->sect->common.flags;
7560 if (f1 == f2)
7561 return 0;
7562 return f1 < f2 ? -1 : 1;
7565 /* Output the definitions of all object_blocks. */
7567 void
7568 output_object_blocks (void)
7570 vec<object_block *, va_heap> v;
7571 v.create (object_block_htab->elements ());
7572 object_block *obj;
7573 hash_table<object_block_hasher>::iterator hi;
7575 FOR_EACH_HASH_TABLE_ELEMENT (*object_block_htab, obj, object_block *, hi)
7576 v.quick_push (obj);
7578 /* Sort them in order to output them in a deterministic manner,
7579 otherwise we may get .rodata sections in different orders with
7580 and without -g. */
7581 v.qsort (output_object_block_compare);
7582 unsigned i;
7583 FOR_EACH_VEC_ELT (v, i, obj)
7584 output_object_block (obj);
7586 v.release ();
7589 /* This function provides a possible implementation of the
7590 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7591 by -frecord-gcc-switches it creates a new mergeable, string section in the
7592 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7593 contains the switches in ASCII format.
7595 FIXME: This code does not correctly handle double quote characters
7596 that appear inside strings, (it strips them rather than preserving them).
7597 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7598 characters - instead it treats them as sub-string separators. Since
7599 we want to emit NUL strings terminators into the object file we have to use
7600 ASM_OUTPUT_SKIP. */
7603 elf_record_gcc_switches (print_switch_type type, const char * name)
7605 switch (type)
7607 case SWITCH_TYPE_PASSED:
7608 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7609 ASM_OUTPUT_SKIP (asm_out_file, HOST_WIDE_INT_1U);
7610 break;
7612 case SWITCH_TYPE_DESCRIPTIVE:
7613 if (name == NULL)
7615 /* Distinguish between invocations where name is NULL. */
7616 static bool started = false;
7618 if (!started)
7620 section * sec;
7622 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7623 SECTION_DEBUG
7624 | SECTION_MERGE
7625 | SECTION_STRINGS
7626 | (SECTION_ENTSIZE & 1),
7627 NULL);
7628 switch_to_section (sec);
7629 started = true;
7633 default:
7634 break;
7637 /* The return value is currently ignored by the caller, but must be 0.
7638 For -fverbose-asm the return value would be the number of characters
7639 emitted into the assembler file. */
7640 return 0;
7643 /* Emit text to declare externally defined symbols. It is needed to
7644 properly support non-default visibility. */
7645 void
7646 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7647 tree decl,
7648 const char *name ATTRIBUTE_UNUSED)
7650 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7651 set in order to avoid putting out names that are never really
7652 used. Always output visibility specified in the source. */
7653 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7654 && (DECL_VISIBILITY_SPECIFIED (decl)
7655 || targetm.binds_local_p (decl)))
7656 maybe_assemble_visibility (decl);
7659 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7661 void
7662 default_asm_output_source_filename (FILE *file, const char *name)
7664 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7665 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7666 #else
7667 fprintf (file, "\t.file\t");
7668 output_quoted_string (file, name);
7669 putc ('\n', file);
7670 #endif
7673 /* Output a file name in the form wanted by System V. */
7675 void
7676 output_file_directive (FILE *asm_file, const char *input_name)
7678 int len;
7679 const char *na;
7681 if (input_name == NULL)
7682 input_name = "<stdin>";
7683 else
7684 input_name = remap_debug_filename (input_name);
7686 len = strlen (input_name);
7687 na = input_name + len;
7689 /* NA gets INPUT_NAME sans directory names. */
7690 while (na > input_name)
7692 if (IS_DIR_SEPARATOR (na[-1]))
7693 break;
7694 na--;
7697 targetm.asm_out.output_source_filename (asm_file, na);
7700 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7701 EXP. */
7703 make_debug_expr_from_rtl (const_rtx exp)
7705 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7706 machine_mode mode = GET_MODE (exp);
7707 rtx dval;
7709 DECL_ARTIFICIAL (ddecl) = 1;
7710 if (REG_P (exp) && REG_EXPR (exp))
7711 type = TREE_TYPE (REG_EXPR (exp));
7712 else if (MEM_P (exp) && MEM_EXPR (exp))
7713 type = TREE_TYPE (MEM_EXPR (exp));
7714 else
7715 type = NULL_TREE;
7716 if (type && TYPE_MODE (type) == mode)
7717 TREE_TYPE (ddecl) = type;
7718 else
7719 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7720 SET_DECL_MODE (ddecl, mode);
7721 dval = gen_rtx_DEBUG_EXPR (mode);
7722 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7723 SET_DECL_RTL (ddecl, dval);
7724 return dval;
7727 #ifdef ELF_ASCII_ESCAPES
7728 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7730 void
7731 default_elf_asm_output_limited_string (FILE *f, const char *s)
7733 int escape;
7734 unsigned char c;
7736 fputs (STRING_ASM_OP, f);
7737 putc ('"', f);
7738 while (*s != '\0')
7740 c = *s;
7741 escape = ELF_ASCII_ESCAPES[c];
7742 switch (escape)
7744 case 0:
7745 putc (c, f);
7746 break;
7747 case 1:
7748 putc ('\\', f);
7749 putc ('0'+((c>>6)&7), f);
7750 putc ('0'+((c>>3)&7), f);
7751 putc ('0'+(c&7), f);
7752 break;
7753 default:
7754 putc ('\\', f);
7755 putc (escape, f);
7756 break;
7758 s++;
7760 putc ('\"', f);
7761 putc ('\n', f);
7764 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7766 void
7767 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7769 const char *limit = s + len;
7770 const char *last_null = NULL;
7771 unsigned bytes_in_chunk = 0;
7772 unsigned char c;
7773 int escape;
7775 for (; s < limit; s++)
7777 const char *p;
7779 if (bytes_in_chunk >= 60)
7781 putc ('\"', f);
7782 putc ('\n', f);
7783 bytes_in_chunk = 0;
7786 if (s > last_null)
7788 for (p = s; p < limit && *p != '\0'; p++)
7789 continue;
7790 last_null = p;
7792 else
7793 p = last_null;
7795 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7797 if (bytes_in_chunk > 0)
7799 putc ('\"', f);
7800 putc ('\n', f);
7801 bytes_in_chunk = 0;
7804 default_elf_asm_output_limited_string (f, s);
7805 s = p;
7807 else
7809 if (bytes_in_chunk == 0)
7810 fputs (ASCII_DATA_ASM_OP "\"", f);
7812 c = *s;
7813 escape = ELF_ASCII_ESCAPES[c];
7814 switch (escape)
7816 case 0:
7817 putc (c, f);
7818 bytes_in_chunk++;
7819 break;
7820 case 1:
7821 putc ('\\', f);
7822 putc ('0'+((c>>6)&7), f);
7823 putc ('0'+((c>>3)&7), f);
7824 putc ('0'+(c&7), f);
7825 bytes_in_chunk += 4;
7826 break;
7827 default:
7828 putc ('\\', f);
7829 putc (escape, f);
7830 bytes_in_chunk += 2;
7831 break;
7837 if (bytes_in_chunk > 0)
7839 putc ('\"', f);
7840 putc ('\n', f);
7843 #endif
7845 static GTY(()) section *elf_init_array_section;
7846 static GTY(()) section *elf_fini_array_section;
7848 static section *
7849 get_elf_initfini_array_priority_section (int priority,
7850 bool constructor_p)
7852 section *sec;
7853 if (priority != DEFAULT_INIT_PRIORITY)
7855 char buf[18];
7856 sprintf (buf, "%s.%.5u",
7857 constructor_p ? ".init_array" : ".fini_array",
7858 priority);
7859 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7861 else
7863 if (constructor_p)
7865 if (elf_init_array_section == NULL)
7866 elf_init_array_section
7867 = get_section (".init_array",
7868 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7869 sec = elf_init_array_section;
7871 else
7873 if (elf_fini_array_section == NULL)
7874 elf_fini_array_section
7875 = get_section (".fini_array",
7876 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7877 sec = elf_fini_array_section;
7880 return sec;
7883 /* Use .init_array section for constructors. */
7885 void
7886 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7888 section *sec = get_elf_initfini_array_priority_section (priority,
7889 true);
7890 assemble_addr_to_section (symbol, sec);
7893 /* Use .fini_array section for destructors. */
7895 void
7896 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7898 section *sec = get_elf_initfini_array_priority_section (priority,
7899 false);
7900 assemble_addr_to_section (symbol, sec);
7903 /* Default TARGET_ASM_OUTPUT_IDENT hook.
7905 This is a bit of a cheat. The real default is a no-op, but this
7906 hook is the default for all targets with a .ident directive. */
7908 void
7909 default_asm_output_ident_directive (const char *ident_str)
7911 const char *ident_asm_op = "\t.ident\t";
7913 /* If we are still in the front end, do not write out the string
7914 to asm_out_file. Instead, add a fake top-level asm statement.
7915 This allows the front ends to use this hook without actually
7916 writing to asm_out_file, to handle #ident or Pragma Ident. */
7917 if (symtab->state == PARSING)
7919 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
7920 symtab->finalize_toplevel_asm (build_string (strlen (buf), buf));
7922 else
7923 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
7927 /* This function ensures that vtable_map variables are not only
7928 in the comdat section, but that each variable has its own unique
7929 comdat name. Without this the variables end up in the same section
7930 with a single comdat name.
7932 FIXME: resolve_unique_section needs to deal better with
7933 decls with both DECL_SECTION_NAME and DECL_ONE_ONLY. Once
7934 that is fixed, this if-else statement can be replaced with
7935 a single call to "switch_to_section (sect)". */
7937 static void
7938 handle_vtv_comdat_section (section *sect, const_tree decl ATTRIBUTE_UNUSED)
7940 #if defined (OBJECT_FORMAT_ELF)
7941 targetm.asm_out.named_section (sect->named.name,
7942 sect->named.common.flags
7943 | SECTION_LINKONCE,
7944 DECL_NAME (decl));
7945 in_section = sect;
7946 #else
7947 /* Neither OBJECT_FORMAT_PE, nor OBJECT_FORMAT_COFF is set here.
7948 Therefore the following check is used.
7949 In case a the target is PE or COFF a comdat group section
7950 is created, e.g. .vtable_map_vars$foo. The linker places
7951 everything in .vtable_map_vars at the end.
7953 A fix could be made in
7954 gcc/config/i386/winnt.c: i386_pe_unique_section. */
7955 if (TARGET_PECOFF)
7957 char *name;
7959 if (TREE_CODE (DECL_NAME (decl)) == IDENTIFIER_NODE)
7960 name = ACONCAT ((sect->named.name, "$",
7961 IDENTIFIER_POINTER (DECL_NAME (decl)), NULL));
7962 else
7963 name = ACONCAT ((sect->named.name, "$",
7964 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (DECL_NAME (decl))),
7965 NULL));
7967 targetm.asm_out.named_section (name,
7968 sect->named.common.flags
7969 | SECTION_LINKONCE,
7970 DECL_NAME (decl));
7971 in_section = sect;
7973 else
7974 switch_to_section (sect);
7975 #endif
7978 #include "gt-varasm.h"