runtime: don't assume that _ = *s will panic if s is nil
[official-gcc.git] / gcc / varasm.c
blobfbaebc1b5c024ab1a5792c00f60b4531b552e06d
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 /* Do any machine/system dependent processing of the function name. */
1829 #ifdef ASM_DECLARE_FUNCTION_NAME
1830 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1831 #else
1832 /* Standard thing is just output label for the function. */
1833 ASM_OUTPUT_FUNCTION_LABEL (asm_out_file, fnname, current_function_decl);
1834 #endif /* ASM_DECLARE_FUNCTION_NAME */
1836 if (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (decl)))
1837 saw_no_split_stack = true;
1840 /* Output assembler code associated with defining the size of the
1841 function. DECL describes the function. NAME is the function's name. */
1843 void
1844 assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED)
1846 #ifdef ASM_DECLARE_FUNCTION_SIZE
1847 /* We could have switched section in the middle of the function. */
1848 if (crtl->has_bb_partition)
1849 switch_to_section (function_section (decl));
1850 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1851 #endif
1852 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1854 output_constant_pool (fnname, decl);
1855 switch_to_section (function_section (decl)); /* need to switch back */
1857 /* Output labels for end of hot/cold text sections (to be used by
1858 debug info.) */
1859 if (crtl->has_bb_partition)
1861 section *save_text_section;
1863 save_text_section = in_section;
1864 switch_to_section (unlikely_text_section ());
1865 #ifdef ASM_DECLARE_COLD_FUNCTION_SIZE
1866 if (cold_function_name != NULL_TREE)
1867 ASM_DECLARE_COLD_FUNCTION_SIZE (asm_out_file,
1868 IDENTIFIER_POINTER (cold_function_name),
1869 decl);
1870 #endif
1871 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label);
1872 if (first_function_block_is_cold)
1873 switch_to_section (text_section);
1874 else
1875 switch_to_section (function_section (decl));
1876 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label);
1877 switch_to_section (save_text_section);
1881 /* Assemble code to leave SIZE bytes of zeros. */
1883 void
1884 assemble_zeros (unsigned HOST_WIDE_INT size)
1886 /* Do no output if -fsyntax-only. */
1887 if (flag_syntax_only)
1888 return;
1890 #ifdef ASM_NO_SKIP_IN_TEXT
1891 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1892 so we must output 0s explicitly in the text section. */
1893 if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0)
1895 unsigned HOST_WIDE_INT i;
1896 for (i = 0; i < size; i++)
1897 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1899 else
1900 #endif
1901 if (size > 0)
1902 ASM_OUTPUT_SKIP (asm_out_file, size);
1905 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1907 void
1908 assemble_align (int align)
1910 if (align > BITS_PER_UNIT)
1912 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1916 /* Assemble a string constant with the specified C string as contents. */
1918 void
1919 assemble_string (const char *p, int size)
1921 int pos = 0;
1922 int maximum = 2000;
1924 /* If the string is very long, split it up. */
1926 while (pos < size)
1928 int thissize = size - pos;
1929 if (thissize > maximum)
1930 thissize = maximum;
1932 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1934 pos += thissize;
1935 p += thissize;
1940 /* A noswitch_section_callback for lcomm_section. */
1942 static bool
1943 emit_local (tree decl ATTRIBUTE_UNUSED,
1944 const char *name ATTRIBUTE_UNUSED,
1945 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1946 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1948 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1949 unsigned int align = symtab_node::get (decl)->definition_alignment ();
1950 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name,
1951 size, align);
1952 return true;
1953 #elif defined ASM_OUTPUT_ALIGNED_LOCAL
1954 unsigned int align = symtab_node::get (decl)->definition_alignment ();
1955 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, align);
1956 return true;
1957 #else
1958 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1959 return false;
1960 #endif
1963 /* A noswitch_section_callback for bss_noswitch_section. */
1965 #if defined ASM_OUTPUT_ALIGNED_BSS
1966 static bool
1967 emit_bss (tree decl ATTRIBUTE_UNUSED,
1968 const char *name ATTRIBUTE_UNUSED,
1969 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1970 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1972 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size,
1973 get_variable_align (decl));
1974 return true;
1976 #endif
1978 /* A noswitch_section_callback for comm_section. */
1980 static bool
1981 emit_common (tree decl ATTRIBUTE_UNUSED,
1982 const char *name ATTRIBUTE_UNUSED,
1983 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1984 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1986 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1987 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name,
1988 size, get_variable_align (decl));
1989 return true;
1990 #elif defined ASM_OUTPUT_ALIGNED_COMMON
1991 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size,
1992 get_variable_align (decl));
1993 return true;
1994 #else
1995 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
1996 return false;
1997 #endif
2000 /* A noswitch_section_callback for tls_comm_section. */
2002 static bool
2003 emit_tls_common (tree decl ATTRIBUTE_UNUSED,
2004 const char *name ATTRIBUTE_UNUSED,
2005 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2006 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2008 #ifdef ASM_OUTPUT_TLS_COMMON
2009 ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size);
2010 return true;
2011 #else
2012 sorry ("thread-local COMMON data not implemented");
2013 return true;
2014 #endif
2017 /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT.
2018 NAME is the name of DECL's SYMBOL_REF. */
2020 static void
2021 assemble_noswitch_variable (tree decl, const char *name, section *sect,
2022 unsigned int align)
2024 unsigned HOST_WIDE_INT size, rounded;
2026 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2027 rounded = size;
2029 if ((flag_sanitize & SANITIZE_ADDRESS) && asan_protect_global (decl))
2030 size += asan_red_zone_size (size);
2032 /* Don't allocate zero bytes of common,
2033 since that means "undefined external" in the linker. */
2034 if (size == 0)
2035 rounded = 1;
2037 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2038 so that each uninitialized object starts on such a boundary. */
2039 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
2040 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2041 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2043 if (!sect->noswitch.callback (decl, name, size, rounded)
2044 && (unsigned HOST_WIDE_INT) (align / BITS_PER_UNIT) > rounded)
2045 error ("requested alignment for %q+D is greater than "
2046 "implemented alignment of %wu", decl, rounded);
2049 /* A subroutine of assemble_variable. Output the label and contents of
2050 DECL, whose address is a SYMBOL_REF with name NAME. DONT_OUTPUT_DATA
2051 is as for assemble_variable. */
2053 static void
2054 assemble_variable_contents (tree decl, const char *name,
2055 bool dont_output_data)
2057 /* Do any machine/system dependent processing of the object. */
2058 #ifdef ASM_DECLARE_OBJECT_NAME
2059 last_assemble_variable_decl = decl;
2060 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
2061 #else
2062 /* Standard thing is just output label for the object. */
2063 ASM_OUTPUT_LABEL (asm_out_file, name);
2064 #endif /* ASM_DECLARE_OBJECT_NAME */
2066 if (!dont_output_data)
2068 /* Caller is supposed to use varpool_get_constructor when it wants
2069 to output the body. */
2070 gcc_assert (!in_lto_p || DECL_INITIAL (decl) != error_mark_node);
2071 if (DECL_INITIAL (decl)
2072 && DECL_INITIAL (decl) != error_mark_node
2073 && !initializer_zerop (DECL_INITIAL (decl)))
2074 /* Output the actual data. */
2075 output_constant (DECL_INITIAL (decl),
2076 tree_to_uhwi (DECL_SIZE_UNIT (decl)),
2077 get_variable_align (decl),
2078 false);
2079 else
2080 /* Leave space for it. */
2081 assemble_zeros (tree_to_uhwi (DECL_SIZE_UNIT (decl)));
2082 targetm.asm_out.decl_end ();
2086 /* Write out assembly for the variable DECL, which is not defined in
2087 the current translation unit. */
2088 void
2089 assemble_undefined_decl (tree decl)
2091 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
2092 targetm.asm_out.assemble_undefined_decl (asm_out_file, name, decl);
2095 /* Assemble everything that is needed for a variable or function declaration.
2096 Not used for automatic variables, and not used for function definitions.
2097 Should not be called for variables of incomplete structure type.
2099 TOP_LEVEL is nonzero if this variable has file scope.
2100 AT_END is nonzero if this is the special handling, at end of compilation,
2101 to define things that have had only tentative definitions.
2102 DONT_OUTPUT_DATA if nonzero means don't actually output the
2103 initial value (that will be done by the caller). */
2105 void
2106 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
2107 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
2109 const char *name;
2110 rtx decl_rtl, symbol;
2111 section *sect;
2112 unsigned int align;
2113 bool asan_protected = false;
2115 /* This function is supposed to handle VARIABLES. Ensure we have one. */
2116 gcc_assert (VAR_P (decl));
2118 /* Emulated TLS had better not get this far. */
2119 gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl));
2121 last_assemble_variable_decl = 0;
2123 /* Normally no need to say anything here for external references,
2124 since assemble_external is called by the language-specific code
2125 when a declaration is first seen. */
2127 if (DECL_EXTERNAL (decl))
2128 return;
2130 /* Do nothing for global register variables. */
2131 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
2133 TREE_ASM_WRITTEN (decl) = 1;
2134 return;
2137 /* If type was incomplete when the variable was declared,
2138 see if it is complete now. */
2140 if (DECL_SIZE (decl) == 0)
2141 layout_decl (decl, 0);
2143 /* Still incomplete => don't allocate it; treat the tentative defn
2144 (which is what it must have been) as an `extern' reference. */
2146 if (!dont_output_data && DECL_SIZE (decl) == 0)
2148 error ("storage size of %q+D isn%'t known", decl);
2149 TREE_ASM_WRITTEN (decl) = 1;
2150 return;
2153 /* The first declaration of a variable that comes through this function
2154 decides whether it is global (in C, has external linkage)
2155 or local (in C, has internal linkage). So do nothing more
2156 if this function has already run. */
2158 if (TREE_ASM_WRITTEN (decl))
2159 return;
2161 /* Make sure targetm.encode_section_info is invoked before we set
2162 ASM_WRITTEN. */
2163 decl_rtl = DECL_RTL (decl);
2165 TREE_ASM_WRITTEN (decl) = 1;
2167 /* Do no output if -fsyntax-only. */
2168 if (flag_syntax_only)
2169 return;
2171 if (! dont_output_data
2172 && ! valid_constant_size_p (DECL_SIZE_UNIT (decl)))
2174 error ("size of variable %q+D is too large", decl);
2175 return;
2178 gcc_assert (MEM_P (decl_rtl));
2179 gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF);
2180 symbol = XEXP (decl_rtl, 0);
2182 /* If this symbol belongs to the tree constant pool, output the constant
2183 if it hasn't already been written. */
2184 if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
2186 tree decl = SYMBOL_REF_DECL (symbol);
2187 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
2188 output_constant_def_contents (symbol);
2189 return;
2192 app_disable ();
2194 name = XSTR (symbol, 0);
2195 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
2196 notice_global_symbol (decl);
2198 /* Compute the alignment of this data. */
2200 align_variable (decl, dont_output_data);
2202 if ((flag_sanitize & SANITIZE_ADDRESS)
2203 && asan_protect_global (decl))
2205 asan_protected = true;
2206 SET_DECL_ALIGN (decl, MAX (DECL_ALIGN (decl),
2207 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT));
2210 set_mem_align (decl_rtl, DECL_ALIGN (decl));
2212 align = get_variable_align (decl);
2214 if (TREE_PUBLIC (decl))
2215 maybe_assemble_visibility (decl);
2217 if (DECL_PRESERVE_P (decl))
2218 targetm.asm_out.mark_decl_preserved (name);
2220 /* First make the assembler name(s) global if appropriate. */
2221 sect = get_variable_section (decl, false);
2222 if (TREE_PUBLIC (decl)
2223 && (sect->common.flags & SECTION_COMMON) == 0)
2224 globalize_decl (decl);
2226 /* Output any data that we will need to use the address of. */
2227 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
2228 output_addressed_constants (DECL_INITIAL (decl));
2230 /* dbxout.c needs to know this. */
2231 if (sect && (sect->common.flags & SECTION_CODE) != 0)
2232 DECL_IN_TEXT_SECTION (decl) = 1;
2234 /* If the decl is part of an object_block, make sure that the decl
2235 has been positioned within its block, but do not write out its
2236 definition yet. output_object_blocks will do that later. */
2237 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
2239 gcc_assert (!dont_output_data);
2240 place_block_symbol (symbol);
2242 else if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
2243 assemble_noswitch_variable (decl, name, sect, align);
2244 else
2246 /* Special-case handling of vtv comdat sections. */
2247 if (sect->named.name
2248 && (strcmp (sect->named.name, ".vtable_map_vars") == 0))
2249 handle_vtv_comdat_section (sect, decl);
2250 else
2251 switch_to_section (sect);
2252 if (align > BITS_PER_UNIT)
2253 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2254 assemble_variable_contents (decl, name, dont_output_data);
2255 if (asan_protected)
2257 unsigned HOST_WIDE_INT int size
2258 = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2259 assemble_zeros (asan_red_zone_size (size));
2265 /* Given a function declaration (FN_DECL), this function assembles the
2266 function into the .preinit_array section. */
2268 void
2269 assemble_vtv_preinit_initializer (tree fn_decl)
2271 section *sect;
2272 unsigned flags = SECTION_WRITE;
2273 rtx symbol = XEXP (DECL_RTL (fn_decl), 0);
2275 flags |= SECTION_NOTYPE;
2276 sect = get_section (".preinit_array", flags, fn_decl);
2277 switch_to_section (sect);
2278 assemble_addr_to_section (symbol, sect);
2281 /* Return 1 if type TYPE contains any pointers. */
2283 static int
2284 contains_pointers_p (tree type)
2286 switch (TREE_CODE (type))
2288 case POINTER_TYPE:
2289 case REFERENCE_TYPE:
2290 /* I'm not sure whether OFFSET_TYPE needs this treatment,
2291 so I'll play safe and return 1. */
2292 case OFFSET_TYPE:
2293 return 1;
2295 case RECORD_TYPE:
2296 case UNION_TYPE:
2297 case QUAL_UNION_TYPE:
2299 tree fields;
2300 /* For a type that has fields, see if the fields have pointers. */
2301 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2302 if (TREE_CODE (fields) == FIELD_DECL
2303 && contains_pointers_p (TREE_TYPE (fields)))
2304 return 1;
2305 return 0;
2308 case ARRAY_TYPE:
2309 /* An array type contains pointers if its element type does. */
2310 return contains_pointers_p (TREE_TYPE (type));
2312 default:
2313 return 0;
2317 /* We delay assemble_external processing until
2318 the compilation unit is finalized. This is the best we can do for
2319 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2320 it all the way to final. See PR 17982 for further discussion. */
2321 static GTY(()) tree pending_assemble_externals;
2323 #ifdef ASM_OUTPUT_EXTERNAL
2324 /* Some targets delay some output to final using TARGET_ASM_FILE_END.
2325 As a result, assemble_external can be called after the list of externals
2326 is processed and the pointer set destroyed. */
2327 static bool pending_assemble_externals_processed;
2329 /* Avoid O(external_decls**2) lookups in the pending_assemble_externals
2330 TREE_LIST in assemble_external. */
2331 static hash_set<tree> *pending_assemble_externals_set;
2333 /* True if DECL is a function decl for which no out-of-line copy exists.
2334 It is assumed that DECL's assembler name has been set. */
2336 static bool
2337 incorporeal_function_p (tree decl)
2339 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
2341 const char *name;
2343 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2344 && (DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA
2345 || DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA_WITH_ALIGN))
2346 return true;
2348 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2349 /* Atomic or sync builtins which have survived this far will be
2350 resolved externally and therefore are not incorporeal. */
2351 if (strncmp (name, "__builtin_", 10) == 0)
2352 return true;
2354 return false;
2357 /* Actually do the tests to determine if this is necessary, and invoke
2358 ASM_OUTPUT_EXTERNAL. */
2359 static void
2360 assemble_external_real (tree decl)
2362 rtx rtl = DECL_RTL (decl);
2364 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2365 && !SYMBOL_REF_USED (XEXP (rtl, 0))
2366 && !incorporeal_function_p (decl))
2368 /* Some systems do require some output. */
2369 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2370 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2373 #endif
2375 void
2376 process_pending_assemble_externals (void)
2378 #ifdef ASM_OUTPUT_EXTERNAL
2379 tree list;
2380 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2381 assemble_external_real (TREE_VALUE (list));
2383 pending_assemble_externals = 0;
2384 pending_assemble_externals_processed = true;
2385 delete pending_assemble_externals_set;
2386 #endif
2389 /* This TREE_LIST contains any weak symbol declarations waiting
2390 to be emitted. */
2391 static GTY(()) tree weak_decls;
2393 /* Output something to declare an external symbol to the assembler,
2394 and qualifiers such as weakness. (Most assemblers don't need
2395 extern declaration, so we normally output nothing.) Do nothing if
2396 DECL is not external. */
2398 void
2399 assemble_external (tree decl ATTRIBUTE_UNUSED)
2401 /* Make sure that the ASM_OUT_FILE is open.
2402 If it's not, we should not be calling this function. */
2403 gcc_assert (asm_out_file);
2405 /* In a perfect world, the following condition would be true.
2406 Sadly, the Java and Go front ends emit assembly *from the front end*,
2407 bypassing the call graph. See PR52739. Fix before GCC 4.8. */
2408 #if 0
2409 /* This function should only be called if we are expanding, or have
2410 expanded, to RTL.
2411 Ideally, only final.c would be calling this function, but it is
2412 not clear whether that would break things somehow. See PR 17982
2413 for further discussion. */
2414 gcc_assert (state == EXPANSION
2415 || state == FINISHED);
2416 #endif
2418 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2419 return;
2421 /* We want to output annotation for weak and external symbols at
2422 very last to check if they are references or not. */
2424 if (TARGET_SUPPORTS_WEAK
2425 && DECL_WEAK (decl)
2426 /* TREE_STATIC is a weird and abused creature which is not
2427 generally the right test for whether an entity has been
2428 locally emitted, inlined or otherwise not-really-extern, but
2429 for declarations that can be weak, it happens to be
2430 match. */
2431 && !TREE_STATIC (decl)
2432 && lookup_attribute ("weak", DECL_ATTRIBUTES (decl))
2433 && value_member (decl, weak_decls) == NULL_TREE)
2434 weak_decls = tree_cons (NULL, decl, weak_decls);
2436 #ifdef ASM_OUTPUT_EXTERNAL
2437 if (pending_assemble_externals_processed)
2439 assemble_external_real (decl);
2440 return;
2443 if (! pending_assemble_externals_set->add (decl))
2444 pending_assemble_externals = tree_cons (NULL, decl,
2445 pending_assemble_externals);
2446 #endif
2449 /* Similar, for calling a library function FUN. */
2451 void
2452 assemble_external_libcall (rtx fun)
2454 /* Declare library function name external when first used, if nec. */
2455 if (! SYMBOL_REF_USED (fun))
2457 SYMBOL_REF_USED (fun) = 1;
2458 targetm.asm_out.external_libcall (fun);
2462 /* Assemble a label named NAME. */
2464 void
2465 assemble_label (FILE *file, const char *name)
2467 ASM_OUTPUT_LABEL (file, name);
2470 /* Set the symbol_referenced flag for ID. */
2471 void
2472 mark_referenced (tree id)
2474 TREE_SYMBOL_REFERENCED (id) = 1;
2477 /* Set the symbol_referenced flag for DECL and notify callgraph. */
2478 void
2479 mark_decl_referenced (tree decl)
2481 if (TREE_CODE (decl) == FUNCTION_DECL)
2483 /* Extern inline functions don't become needed when referenced.
2484 If we know a method will be emitted in other TU and no new
2485 functions can be marked reachable, just use the external
2486 definition. */
2487 struct cgraph_node *node = cgraph_node::get_create (decl);
2488 if (!DECL_EXTERNAL (decl)
2489 && !node->definition)
2490 node->mark_force_output ();
2492 else if (VAR_P (decl))
2494 varpool_node *node = varpool_node::get_create (decl);
2495 /* C++ frontend use mark_decl_references to force COMDAT variables
2496 to be output that might appear dead otherwise. */
2497 node->force_output = true;
2499 /* else do nothing - we can get various sorts of CST nodes here,
2500 which do not need to be marked. */
2504 /* Output to FILE (an assembly file) a reference to NAME. If NAME
2505 starts with a *, the rest of NAME is output verbatim. Otherwise
2506 NAME is transformed in a target-specific way (usually by the
2507 addition of an underscore). */
2509 void
2510 assemble_name_raw (FILE *file, const char *name)
2512 if (name[0] == '*')
2513 fputs (&name[1], file);
2514 else
2515 ASM_OUTPUT_LABELREF (file, name);
2518 /* Like assemble_name_raw, but should be used when NAME might refer to
2519 an entity that is also represented as a tree (like a function or
2520 variable). If NAME does refer to such an entity, that entity will
2521 be marked as referenced. */
2523 void
2524 assemble_name (FILE *file, const char *name)
2526 const char *real_name;
2527 tree id;
2529 real_name = targetm.strip_name_encoding (name);
2531 id = maybe_get_identifier (real_name);
2532 if (id)
2534 tree id_orig = id;
2536 mark_referenced (id);
2537 ultimate_transparent_alias_target (&id);
2538 if (id != id_orig)
2539 name = IDENTIFIER_POINTER (id);
2540 gcc_assert (! TREE_CHAIN (id));
2543 assemble_name_raw (file, name);
2546 /* Allocate SIZE bytes writable static space with a gensym name
2547 and return an RTX to refer to its address. */
2550 assemble_static_space (unsigned HOST_WIDE_INT size)
2552 char name[17];
2553 const char *namestring;
2554 rtx x;
2556 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2557 ++const_labelno;
2558 namestring = ggc_strdup (name);
2560 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2561 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2563 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2564 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2565 BIGGEST_ALIGNMENT);
2566 #else
2567 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2568 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2569 #else
2571 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2572 so that each uninitialized object starts on such a boundary. */
2573 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2574 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2575 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2576 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2577 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2578 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2580 #endif
2581 #endif
2582 return x;
2585 /* Assemble the static constant template for function entry trampolines.
2586 This is done at most once per compilation.
2587 Returns an RTX for the address of the template. */
2589 static GTY(()) rtx initial_trampoline;
2592 assemble_trampoline_template (void)
2594 char label[256];
2595 const char *name;
2596 int align;
2597 rtx symbol;
2599 gcc_assert (targetm.asm_out.trampoline_template != NULL);
2601 if (initial_trampoline)
2602 return initial_trampoline;
2604 /* By default, put trampoline templates in read-only data section. */
2606 #ifdef TRAMPOLINE_SECTION
2607 switch_to_section (TRAMPOLINE_SECTION);
2608 #else
2609 switch_to_section (readonly_data_section);
2610 #endif
2612 /* Write the assembler code to define one. */
2613 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2614 if (align > 0)
2615 ASM_OUTPUT_ALIGN (asm_out_file, align);
2617 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2618 targetm.asm_out.trampoline_template (asm_out_file);
2620 /* Record the rtl to refer to it. */
2621 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2622 name = ggc_strdup (label);
2623 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2624 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2626 initial_trampoline = gen_const_mem (BLKmode, symbol);
2627 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2628 set_mem_size (initial_trampoline, TRAMPOLINE_SIZE);
2630 return initial_trampoline;
2633 /* A and B are either alignments or offsets. Return the minimum alignment
2634 that may be assumed after adding the two together. */
2636 static inline unsigned
2637 min_align (unsigned int a, unsigned int b)
2639 return least_bit_hwi (a | b);
2642 /* Return the assembler directive for creating a given kind of integer
2643 object. SIZE is the number of bytes in the object and ALIGNED_P
2644 indicates whether it is known to be aligned. Return NULL if the
2645 assembly dialect has no such directive.
2647 The returned string should be printed at the start of a new line and
2648 be followed immediately by the object's initial value. */
2650 const char *
2651 integer_asm_op (int size, int aligned_p)
2653 struct asm_int_op *ops;
2655 if (aligned_p)
2656 ops = &targetm.asm_out.aligned_op;
2657 else
2658 ops = &targetm.asm_out.unaligned_op;
2660 switch (size)
2662 case 1:
2663 return targetm.asm_out.byte_op;
2664 case 2:
2665 return ops->hi;
2666 case 4:
2667 return ops->si;
2668 case 8:
2669 return ops->di;
2670 case 16:
2671 return ops->ti;
2672 default:
2673 return NULL;
2677 /* Use directive OP to assemble an integer object X. Print OP at the
2678 start of the line, followed immediately by the value of X. */
2680 void
2681 assemble_integer_with_op (const char *op, rtx x)
2683 fputs (op, asm_out_file);
2684 output_addr_const (asm_out_file, x);
2685 fputc ('\n', asm_out_file);
2688 /* The default implementation of the asm_out.integer target hook. */
2690 bool
2691 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2692 unsigned int size ATTRIBUTE_UNUSED,
2693 int aligned_p ATTRIBUTE_UNUSED)
2695 const char *op = integer_asm_op (size, aligned_p);
2696 /* Avoid GAS bugs for large values. Specifically negative values whose
2697 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2698 if (size > UNITS_PER_WORD && size > POINTER_SIZE_UNITS)
2699 return false;
2700 return op && (assemble_integer_with_op (op, x), true);
2703 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2704 the alignment of the integer in bits. Return 1 if we were able to output
2705 the constant, otherwise 0. We must be able to output the constant,
2706 if FORCE is nonzero. */
2708 bool
2709 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2711 int aligned_p;
2713 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2715 /* See if the target hook can handle this kind of object. */
2716 if (targetm.asm_out.integer (x, size, aligned_p))
2717 return true;
2719 /* If the object is a multi-byte one, try splitting it up. Split
2720 it into words it if is multi-word, otherwise split it into bytes. */
2721 if (size > 1)
2723 machine_mode omode, imode;
2724 unsigned int subalign;
2725 unsigned int subsize, i;
2726 enum mode_class mclass;
2728 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2729 subalign = MIN (align, subsize * BITS_PER_UNIT);
2730 if (GET_CODE (x) == CONST_FIXED)
2731 mclass = GET_MODE_CLASS (GET_MODE (x));
2732 else
2733 mclass = MODE_INT;
2735 omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0);
2736 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0);
2738 for (i = 0; i < size; i += subsize)
2740 rtx partial = simplify_subreg (omode, x, imode, i);
2741 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2742 break;
2744 if (i == size)
2745 return true;
2747 /* If we've printed some of it, but not all of it, there's no going
2748 back now. */
2749 gcc_assert (!i);
2752 gcc_assert (!force);
2754 return false;
2757 /* Assemble the floating-point constant D into an object of size MODE. ALIGN
2758 is the alignment of the constant in bits. If REVERSE is true, D is output
2759 in reverse storage order. */
2761 void
2762 assemble_real (REAL_VALUE_TYPE d, machine_mode mode, unsigned int align,
2763 bool reverse)
2765 long data[4] = {0, 0, 0, 0};
2766 int bitsize, nelts, nunits, units_per;
2767 rtx elt;
2769 /* This is hairy. We have a quantity of known size. real_to_target
2770 will put it into an array of *host* longs, 32 bits per element
2771 (even if long is more than 32 bits). We need to determine the
2772 number of array elements that are occupied (nelts) and the number
2773 of *target* min-addressable units that will be occupied in the
2774 object file (nunits). We cannot assume that 32 divides the
2775 mode's bitsize (size * BITS_PER_UNIT) evenly.
2777 size * BITS_PER_UNIT is used here to make sure that padding bits
2778 (which might appear at either end of the value; real_to_target
2779 will include the padding bits in its output array) are included. */
2781 nunits = GET_MODE_SIZE (mode);
2782 bitsize = nunits * BITS_PER_UNIT;
2783 nelts = CEIL (bitsize, 32);
2784 units_per = 32 / BITS_PER_UNIT;
2786 real_to_target (data, &d, mode);
2788 /* Put out the first word with the specified alignment. */
2789 if (reverse)
2790 elt = flip_storage_order (SImode, gen_int_mode (data[nelts - 1], SImode));
2791 else
2792 elt = GEN_INT (data[0]);
2793 assemble_integer (elt, MIN (nunits, units_per), align, 1);
2794 nunits -= units_per;
2796 /* Subsequent words need only 32-bit alignment. */
2797 align = min_align (align, 32);
2799 for (int i = 1; i < nelts; i++)
2801 if (reverse)
2802 elt = flip_storage_order (SImode,
2803 gen_int_mode (data[nelts - 1 - i], SImode));
2804 else
2805 elt = GEN_INT (data[i]);
2806 assemble_integer (elt, MIN (nunits, units_per), align, 1);
2807 nunits -= units_per;
2811 /* Given an expression EXP with a constant value,
2812 reduce it to the sum of an assembler symbol and an integer.
2813 Store them both in the structure *VALUE.
2814 EXP must be reducible. */
2816 struct addr_const {
2817 rtx base;
2818 HOST_WIDE_INT offset;
2821 static void
2822 decode_addr_const (tree exp, struct addr_const *value)
2824 tree target = TREE_OPERAND (exp, 0);
2825 int offset = 0;
2826 rtx x;
2828 while (1)
2830 if (TREE_CODE (target) == COMPONENT_REF
2831 && tree_fits_shwi_p (byte_position (TREE_OPERAND (target, 1))))
2833 offset += int_byte_position (TREE_OPERAND (target, 1));
2834 target = TREE_OPERAND (target, 0);
2836 else if (TREE_CODE (target) == ARRAY_REF
2837 || TREE_CODE (target) == ARRAY_RANGE_REF)
2839 offset += (tree_to_uhwi (TYPE_SIZE_UNIT (TREE_TYPE (target)))
2840 * tree_to_shwi (TREE_OPERAND (target, 1)));
2841 target = TREE_OPERAND (target, 0);
2843 else if (TREE_CODE (target) == MEM_REF
2844 && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR)
2846 offset += mem_ref_offset (target).to_short_addr ();
2847 target = TREE_OPERAND (TREE_OPERAND (target, 0), 0);
2849 else if (TREE_CODE (target) == INDIRECT_REF
2850 && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR
2851 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0))
2852 == ADDR_EXPR)
2853 target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0);
2854 else
2855 break;
2858 switch (TREE_CODE (target))
2860 case VAR_DECL:
2861 case FUNCTION_DECL:
2862 x = DECL_RTL (target);
2863 break;
2865 case LABEL_DECL:
2866 x = gen_rtx_MEM (FUNCTION_MODE,
2867 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2868 break;
2870 case REAL_CST:
2871 case FIXED_CST:
2872 case STRING_CST:
2873 case COMPLEX_CST:
2874 case CONSTRUCTOR:
2875 case INTEGER_CST:
2876 x = output_constant_def (target, 1);
2877 break;
2879 default:
2880 gcc_unreachable ();
2883 gcc_assert (MEM_P (x));
2884 x = XEXP (x, 0);
2886 value->base = x;
2887 value->offset = offset;
2890 static GTY(()) hash_table<tree_descriptor_hasher> *const_desc_htab;
2892 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2894 /* Constant pool accessor function. */
2896 hash_table<tree_descriptor_hasher> *
2897 constant_pool_htab (void)
2899 return const_desc_htab;
2902 /* Compute a hash code for a constant expression. */
2904 hashval_t
2905 tree_descriptor_hasher::hash (constant_descriptor_tree *ptr)
2907 return ptr->hash;
2910 static hashval_t
2911 const_hash_1 (const tree exp)
2913 const char *p;
2914 hashval_t hi;
2915 int len, i;
2916 enum tree_code code = TREE_CODE (exp);
2918 /* Either set P and LEN to the address and len of something to hash and
2919 exit the switch or return a value. */
2921 switch (code)
2923 case INTEGER_CST:
2924 p = (char *) &TREE_INT_CST_ELT (exp, 0);
2925 len = TREE_INT_CST_NUNITS (exp) * sizeof (HOST_WIDE_INT);
2926 break;
2928 case REAL_CST:
2929 return real_hash (TREE_REAL_CST_PTR (exp));
2931 case FIXED_CST:
2932 return fixed_hash (TREE_FIXED_CST_PTR (exp));
2934 case STRING_CST:
2935 p = TREE_STRING_POINTER (exp);
2936 len = TREE_STRING_LENGTH (exp);
2937 break;
2939 case COMPLEX_CST:
2940 return (const_hash_1 (TREE_REALPART (exp)) * 5
2941 + const_hash_1 (TREE_IMAGPART (exp)));
2943 case VECTOR_CST:
2945 unsigned i;
2947 hi = 7 + VECTOR_CST_NELTS (exp);
2949 for (i = 0; i < VECTOR_CST_NELTS (exp); ++i)
2950 hi = hi * 563 + const_hash_1 (VECTOR_CST_ELT (exp, i));
2952 return hi;
2955 case CONSTRUCTOR:
2957 unsigned HOST_WIDE_INT idx;
2958 tree value;
2960 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2962 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
2963 if (value)
2964 hi = hi * 603 + const_hash_1 (value);
2966 return hi;
2969 case ADDR_EXPR:
2970 case FDESC_EXPR:
2972 struct addr_const value;
2974 decode_addr_const (exp, &value);
2975 switch (GET_CODE (value.base))
2977 case SYMBOL_REF:
2978 /* Don't hash the address of the SYMBOL_REF;
2979 only use the offset and the symbol name. */
2980 hi = value.offset;
2981 p = XSTR (value.base, 0);
2982 for (i = 0; p[i] != 0; i++)
2983 hi = ((hi * 613) + (unsigned) (p[i]));
2984 break;
2986 case LABEL_REF:
2987 hi = (value.offset
2988 + CODE_LABEL_NUMBER (label_ref_label (value.base)) * 13);
2989 break;
2991 default:
2992 gcc_unreachable ();
2995 return hi;
2997 case PLUS_EXPR:
2998 case POINTER_PLUS_EXPR:
2999 case MINUS_EXPR:
3000 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
3001 + const_hash_1 (TREE_OPERAND (exp, 1)));
3003 CASE_CONVERT:
3004 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
3006 default:
3007 /* A language specific constant. Just hash the code. */
3008 return code;
3011 /* Compute hashing function. */
3012 hi = len;
3013 for (i = 0; i < len; i++)
3014 hi = ((hi * 613) + (unsigned) (p[i]));
3016 return hi;
3019 /* Wrapper of compare_constant, for the htab interface. */
3020 bool
3021 tree_descriptor_hasher::equal (constant_descriptor_tree *c1,
3022 constant_descriptor_tree *c2)
3024 if (c1->hash != c2->hash)
3025 return 0;
3026 return compare_constant (c1->value, c2->value);
3029 /* Compare t1 and t2, and return 1 only if they are known to result in
3030 the same bit pattern on output. */
3032 static int
3033 compare_constant (const tree t1, const tree t2)
3035 enum tree_code typecode;
3037 if (t1 == NULL_TREE)
3038 return t2 == NULL_TREE;
3039 if (t2 == NULL_TREE)
3040 return 0;
3042 if (TREE_CODE (t1) != TREE_CODE (t2))
3043 return 0;
3045 switch (TREE_CODE (t1))
3047 case INTEGER_CST:
3048 /* Integer constants are the same only if the same width of type. */
3049 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3050 return 0;
3051 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3052 return 0;
3053 return tree_int_cst_equal (t1, t2);
3055 case REAL_CST:
3056 /* Real constants are the same only if the same width of type. */
3057 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3058 return 0;
3060 return real_identical (&TREE_REAL_CST (t1), &TREE_REAL_CST (t2));
3062 case FIXED_CST:
3063 /* Fixed constants are the same only if the same width of type. */
3064 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3065 return 0;
3067 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
3069 case STRING_CST:
3070 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3071 return 0;
3073 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
3074 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
3075 TREE_STRING_LENGTH (t1)));
3077 case COMPLEX_CST:
3078 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
3079 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
3081 case VECTOR_CST:
3083 unsigned i;
3085 if (VECTOR_CST_NELTS (t1) != VECTOR_CST_NELTS (t2))
3086 return 0;
3088 for (i = 0; i < VECTOR_CST_NELTS (t1); ++i)
3089 if (!compare_constant (VECTOR_CST_ELT (t1, i),
3090 VECTOR_CST_ELT (t2, i)))
3091 return 0;
3093 return 1;
3096 case CONSTRUCTOR:
3098 vec<constructor_elt, va_gc> *v1, *v2;
3099 unsigned HOST_WIDE_INT idx;
3101 typecode = TREE_CODE (TREE_TYPE (t1));
3102 if (typecode != TREE_CODE (TREE_TYPE (t2)))
3103 return 0;
3105 if (typecode == ARRAY_TYPE)
3107 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
3108 /* For arrays, check that mode, size and storage order match. */
3109 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
3110 || size_1 == -1
3111 || size_1 != int_size_in_bytes (TREE_TYPE (t2))
3112 || TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (t1))
3113 != TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (t2)))
3114 return 0;
3116 else
3118 /* For record and union constructors, require exact type
3119 equality. */
3120 if (TREE_TYPE (t1) != TREE_TYPE (t2))
3121 return 0;
3124 v1 = CONSTRUCTOR_ELTS (t1);
3125 v2 = CONSTRUCTOR_ELTS (t2);
3126 if (vec_safe_length (v1) != vec_safe_length (v2))
3127 return 0;
3129 for (idx = 0; idx < vec_safe_length (v1); ++idx)
3131 constructor_elt *c1 = &(*v1)[idx];
3132 constructor_elt *c2 = &(*v2)[idx];
3134 /* Check that each value is the same... */
3135 if (!compare_constant (c1->value, c2->value))
3136 return 0;
3137 /* ... and that they apply to the same fields! */
3138 if (typecode == ARRAY_TYPE)
3140 if (!compare_constant (c1->index, c2->index))
3141 return 0;
3143 else
3145 if (c1->index != c2->index)
3146 return 0;
3150 return 1;
3153 case ADDR_EXPR:
3154 case FDESC_EXPR:
3156 struct addr_const value1, value2;
3157 enum rtx_code code;
3158 int ret;
3160 decode_addr_const (t1, &value1);
3161 decode_addr_const (t2, &value2);
3163 if (value1.offset != value2.offset)
3164 return 0;
3166 code = GET_CODE (value1.base);
3167 if (code != GET_CODE (value2.base))
3168 return 0;
3170 switch (code)
3172 case SYMBOL_REF:
3173 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3174 break;
3176 case LABEL_REF:
3177 ret = (CODE_LABEL_NUMBER (label_ref_label (value1.base))
3178 == CODE_LABEL_NUMBER (label_ref_label (value2.base)));
3179 break;
3181 default:
3182 gcc_unreachable ();
3184 return ret;
3187 case PLUS_EXPR:
3188 case POINTER_PLUS_EXPR:
3189 case MINUS_EXPR:
3190 case RANGE_EXPR:
3191 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3192 && compare_constant (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3194 CASE_CONVERT:
3195 case VIEW_CONVERT_EXPR:
3196 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3198 default:
3199 return 0;
3202 gcc_unreachable ();
3205 /* Return the section into which constant EXP should be placed. */
3207 static section *
3208 get_constant_section (tree exp, unsigned int align)
3210 return targetm.asm_out.select_section (exp,
3211 compute_reloc_for_constant (exp),
3212 align);
3215 /* Return the size of constant EXP in bytes. */
3217 static HOST_WIDE_INT
3218 get_constant_size (tree exp)
3220 HOST_WIDE_INT size;
3222 size = int_size_in_bytes (TREE_TYPE (exp));
3223 if (TREE_CODE (exp) == STRING_CST)
3224 size = MAX (TREE_STRING_LENGTH (exp), size);
3225 return size;
3228 /* Subroutine of output_constant_def:
3229 No constant equal to EXP is known to have been output.
3230 Make a constant descriptor to enter EXP in the hash table.
3231 Assign the label number and construct RTL to refer to the
3232 constant's location in memory.
3233 Caller is responsible for updating the hash table. */
3235 static struct constant_descriptor_tree *
3236 build_constant_desc (tree exp)
3238 struct constant_descriptor_tree *desc;
3239 rtx symbol, rtl;
3240 char label[256];
3241 int labelno;
3242 tree decl;
3244 desc = ggc_alloc<constant_descriptor_tree> ();
3245 desc->value = exp;
3247 /* Create a string containing the label name, in LABEL. */
3248 labelno = const_labelno++;
3249 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3251 /* Construct the VAR_DECL associated with the constant. */
3252 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3253 TREE_TYPE (exp));
3254 DECL_ARTIFICIAL (decl) = 1;
3255 DECL_IGNORED_P (decl) = 1;
3256 TREE_READONLY (decl) = 1;
3257 TREE_STATIC (decl) = 1;
3258 TREE_ADDRESSABLE (decl) = 1;
3259 /* We don't set the RTL yet as this would cause varpool to assume that the
3260 variable is referenced. Moreover, it would just be dropped in LTO mode.
3261 Instead we set the flag that will be recognized in make_decl_rtl. */
3262 DECL_IN_CONSTANT_POOL (decl) = 1;
3263 DECL_INITIAL (decl) = desc->value;
3264 /* ??? CONSTANT_ALIGNMENT hasn't been updated for vector types on most
3265 architectures so use DATA_ALIGNMENT as well, except for strings. */
3266 if (TREE_CODE (exp) == STRING_CST)
3268 SET_DECL_ALIGN (decl, CONSTANT_ALIGNMENT (exp, DECL_ALIGN (decl)));
3270 else
3271 align_variable (decl, 0);
3273 /* Now construct the SYMBOL_REF and the MEM. */
3274 if (use_object_blocks_p ())
3276 int align = (TREE_CODE (decl) == CONST_DECL
3277 || (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
3278 ? DECL_ALIGN (decl)
3279 : symtab_node::get (decl)->definition_alignment ());
3280 section *sect = get_constant_section (exp, align);
3281 symbol = create_block_symbol (ggc_strdup (label),
3282 get_block_for_section (sect), -1);
3284 else
3285 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3286 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3287 SET_SYMBOL_REF_DECL (symbol, decl);
3288 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3290 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3291 set_mem_attributes (rtl, exp, 1);
3292 set_mem_alias_set (rtl, 0);
3294 /* Putting EXP into the literal pool might have imposed a different
3295 alignment which should be visible in the RTX as well. */
3296 set_mem_align (rtl, DECL_ALIGN (decl));
3298 /* We cannot share RTX'es in pool entries.
3299 Mark this piece of RTL as required for unsharing. */
3300 RTX_FLAG (rtl, used) = 1;
3302 /* Set flags or add text to the name to record information, such as
3303 that it is a local symbol. If the name is changed, the macro
3304 ASM_OUTPUT_LABELREF will have to know how to strip this
3305 information. This call might invalidate our local variable
3306 SYMBOL; we can't use it afterward. */
3307 targetm.encode_section_info (exp, rtl, true);
3309 desc->rtl = rtl;
3311 return desc;
3314 /* Return an rtx representing a reference to constant data in memory
3315 for the constant expression EXP.
3317 If assembler code for such a constant has already been output,
3318 return an rtx to refer to it.
3319 Otherwise, output such a constant in memory
3320 and generate an rtx for it.
3322 If DEFER is nonzero, this constant can be deferred and output only
3323 if referenced in the function after all optimizations.
3325 `const_desc_table' records which constants already have label strings. */
3328 output_constant_def (tree exp, int defer)
3330 struct constant_descriptor_tree *desc;
3331 struct constant_descriptor_tree key;
3333 /* Look up EXP in the table of constant descriptors. If we didn't find
3334 it, create a new one. */
3335 key.value = exp;
3336 key.hash = const_hash_1 (exp);
3337 constant_descriptor_tree **loc
3338 = const_desc_htab->find_slot_with_hash (&key, key.hash, INSERT);
3340 desc = *loc;
3341 if (desc == 0)
3343 desc = build_constant_desc (exp);
3344 desc->hash = key.hash;
3345 *loc = desc;
3348 maybe_output_constant_def_contents (desc, defer);
3349 return desc->rtl;
3352 /* Subroutine of output_constant_def: Decide whether or not we need to
3353 output the constant DESC now, and if so, do it. */
3354 static void
3355 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3356 int defer)
3358 rtx symbol = XEXP (desc->rtl, 0);
3359 tree exp = desc->value;
3361 if (flag_syntax_only)
3362 return;
3364 if (TREE_ASM_WRITTEN (exp))
3365 /* Already output; don't do it again. */
3366 return;
3368 /* We can always defer constants as long as the context allows
3369 doing so. */
3370 if (defer)
3372 /* Increment n_deferred_constants if it exists. It needs to be at
3373 least as large as the number of constants actually referred to
3374 by the function. If it's too small we'll stop looking too early
3375 and fail to emit constants; if it's too large we'll only look
3376 through the entire function when we could have stopped earlier. */
3377 if (cfun)
3378 n_deferred_constants++;
3379 return;
3382 output_constant_def_contents (symbol);
3385 /* Subroutine of output_constant_def_contents. Output the definition
3386 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3387 constant's alignment in bits. */
3389 static void
3390 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3392 HOST_WIDE_INT size;
3394 size = get_constant_size (exp);
3396 /* Do any machine/system dependent processing of the constant. */
3397 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3399 /* Output the value of EXP. */
3400 output_constant (exp, size, align, false);
3402 targetm.asm_out.decl_end ();
3405 /* We must output the constant data referred to by SYMBOL; do so. */
3407 static void
3408 output_constant_def_contents (rtx symbol)
3410 tree decl = SYMBOL_REF_DECL (symbol);
3411 tree exp = DECL_INITIAL (decl);
3412 bool asan_protected = false;
3414 /* Make sure any other constants whose addresses appear in EXP
3415 are assigned label numbers. */
3416 output_addressed_constants (exp);
3418 /* We are no longer deferring this constant. */
3419 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3421 if ((flag_sanitize & SANITIZE_ADDRESS)
3422 && TREE_CODE (exp) == STRING_CST
3423 && asan_protect_global (exp))
3425 asan_protected = true;
3426 SET_DECL_ALIGN (decl, MAX (DECL_ALIGN (decl),
3427 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT));
3430 /* If the constant is part of an object block, make sure that the
3431 decl has been positioned within its block, but do not write out
3432 its definition yet. output_object_blocks will do that later. */
3433 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3434 place_block_symbol (symbol);
3435 else
3437 int align = (TREE_CODE (decl) == CONST_DECL
3438 || (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
3439 ? DECL_ALIGN (decl)
3440 : symtab_node::get (decl)->definition_alignment ());
3441 switch_to_section (get_constant_section (exp, align));
3442 if (align > BITS_PER_UNIT)
3443 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3444 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3445 if (asan_protected)
3447 HOST_WIDE_INT size = get_constant_size (exp);
3448 assemble_zeros (asan_red_zone_size (size));
3453 /* Look up EXP in the table of constant descriptors. Return the rtl
3454 if it has been emitted, else null. */
3457 lookup_constant_def (tree exp)
3459 struct constant_descriptor_tree key;
3461 key.value = exp;
3462 key.hash = const_hash_1 (exp);
3463 constant_descriptor_tree *desc
3464 = const_desc_htab->find_with_hash (&key, key.hash);
3466 return (desc ? desc->rtl : NULL_RTX);
3469 /* Return a tree representing a reference to constant data in memory
3470 for the constant expression EXP.
3472 This is the counterpart of output_constant_def at the Tree level. */
3474 tree
3475 tree_output_constant_def (tree exp)
3477 struct constant_descriptor_tree *desc, key;
3478 tree decl;
3480 /* Look up EXP in the table of constant descriptors. If we didn't find
3481 it, create a new one. */
3482 key.value = exp;
3483 key.hash = const_hash_1 (exp);
3484 constant_descriptor_tree **loc
3485 = const_desc_htab->find_slot_with_hash (&key, key.hash, INSERT);
3487 desc = *loc;
3488 if (desc == 0)
3490 desc = build_constant_desc (exp);
3491 desc->hash = key.hash;
3492 *loc = desc;
3495 decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3496 varpool_node::finalize_decl (decl);
3497 return decl;
3500 struct GTY((chain_next ("%h.next"), for_user)) constant_descriptor_rtx {
3501 struct constant_descriptor_rtx *next;
3502 rtx mem;
3503 rtx sym;
3504 rtx constant;
3505 HOST_WIDE_INT offset;
3506 hashval_t hash;
3507 machine_mode mode;
3508 unsigned int align;
3509 int labelno;
3510 int mark;
3513 struct const_rtx_desc_hasher : ggc_ptr_hash<constant_descriptor_rtx>
3515 static hashval_t hash (constant_descriptor_rtx *);
3516 static bool equal (constant_descriptor_rtx *, constant_descriptor_rtx *);
3519 /* Used in the hash tables to avoid outputting the same constant
3520 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3521 are output once per function, not once per file. */
3522 /* ??? Only a few targets need per-function constant pools. Most
3523 can use one per-file pool. Should add a targetm bit to tell the
3524 difference. */
3526 struct GTY(()) rtx_constant_pool {
3527 /* Pointers to first and last constant in pool, as ordered by offset. */
3528 struct constant_descriptor_rtx *first;
3529 struct constant_descriptor_rtx *last;
3531 /* Hash facility for making memory-constants from constant rtl-expressions.
3532 It is used on RISC machines where immediate integer arguments and
3533 constant addresses are restricted so that such constants must be stored
3534 in memory. */
3535 hash_table<const_rtx_desc_hasher> *const_rtx_htab;
3537 /* Current offset in constant pool (does not include any
3538 machine-specific header). */
3539 HOST_WIDE_INT offset;
3542 /* Hash and compare functions for const_rtx_htab. */
3544 hashval_t
3545 const_rtx_desc_hasher::hash (constant_descriptor_rtx *desc)
3547 return desc->hash;
3550 bool
3551 const_rtx_desc_hasher::equal (constant_descriptor_rtx *x,
3552 constant_descriptor_rtx *y)
3554 if (x->mode != y->mode)
3555 return 0;
3556 return rtx_equal_p (x->constant, y->constant);
3559 /* Hash one component of a constant. */
3561 static hashval_t
3562 const_rtx_hash_1 (const_rtx x)
3564 unsigned HOST_WIDE_INT hwi;
3565 machine_mode mode;
3566 enum rtx_code code;
3567 hashval_t h;
3568 int i;
3570 code = GET_CODE (x);
3571 mode = GET_MODE (x);
3572 h = (hashval_t) code * 1048573 + mode;
3574 switch (code)
3576 case CONST_INT:
3577 hwi = INTVAL (x);
3579 fold_hwi:
3581 int shift = sizeof (hashval_t) * CHAR_BIT;
3582 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3584 h ^= (hashval_t) hwi;
3585 for (i = 1; i < n; ++i)
3587 hwi >>= shift;
3588 h ^= (hashval_t) hwi;
3591 break;
3593 case CONST_WIDE_INT:
3594 hwi = GET_MODE_PRECISION (mode);
3596 for (i = 0; i < CONST_WIDE_INT_NUNITS (x); i++)
3597 hwi ^= CONST_WIDE_INT_ELT (x, i);
3598 goto fold_hwi;
3601 case CONST_DOUBLE:
3602 if (TARGET_SUPPORTS_WIDE_INT == 0 && mode == VOIDmode)
3604 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3605 goto fold_hwi;
3607 else
3608 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3609 break;
3611 case CONST_FIXED:
3612 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3613 break;
3615 case SYMBOL_REF:
3616 h ^= htab_hash_string (XSTR (x, 0));
3617 break;
3619 case LABEL_REF:
3620 h = h * 251 + CODE_LABEL_NUMBER (label_ref_label (x));
3621 break;
3623 case UNSPEC:
3624 case UNSPEC_VOLATILE:
3625 h = h * 251 + XINT (x, 1);
3626 break;
3628 default:
3629 break;
3632 return h;
3635 /* Compute a hash value for X, which should be a constant. */
3637 static hashval_t
3638 const_rtx_hash (rtx x)
3640 hashval_t h = 0;
3641 subrtx_iterator::array_type array;
3642 FOR_EACH_SUBRTX (iter, array, x, ALL)
3643 h = h * 509 + const_rtx_hash_1 (*iter);
3644 return h;
3648 /* Create and return a new rtx constant pool. */
3650 static struct rtx_constant_pool *
3651 create_constant_pool (void)
3653 struct rtx_constant_pool *pool;
3655 pool = ggc_alloc<rtx_constant_pool> ();
3656 pool->const_rtx_htab = hash_table<const_rtx_desc_hasher>::create_ggc (31);
3657 pool->first = NULL;
3658 pool->last = NULL;
3659 pool->offset = 0;
3660 return pool;
3663 /* Initialize constant pool hashing for a new function. */
3665 void
3666 init_varasm_status (void)
3668 crtl->varasm.pool = create_constant_pool ();
3669 crtl->varasm.deferred_constants = 0;
3672 /* Given a MINUS expression, simplify it if both sides
3673 include the same symbol. */
3676 simplify_subtraction (rtx x)
3678 rtx r = simplify_rtx (x);
3679 return r ? r : x;
3682 /* Given a constant rtx X, make (or find) a memory constant for its value
3683 and return a MEM rtx to refer to it in memory. */
3686 force_const_mem (machine_mode mode, rtx x)
3688 struct constant_descriptor_rtx *desc, tmp;
3689 struct rtx_constant_pool *pool;
3690 char label[256];
3691 rtx def, symbol;
3692 hashval_t hash;
3693 unsigned int align;
3694 constant_descriptor_rtx **slot;
3696 /* If we're not allowed to drop X into the constant pool, don't. */
3697 if (targetm.cannot_force_const_mem (mode, x))
3698 return NULL_RTX;
3700 /* Record that this function has used a constant pool entry. */
3701 crtl->uses_const_pool = 1;
3703 /* Decide which pool to use. */
3704 pool = (targetm.use_blocks_for_constant_p (mode, x)
3705 ? shared_constant_pool
3706 : crtl->varasm.pool);
3708 /* Lookup the value in the hashtable. */
3709 tmp.constant = x;
3710 tmp.mode = mode;
3711 hash = const_rtx_hash (x);
3712 slot = pool->const_rtx_htab->find_slot_with_hash (&tmp, hash, INSERT);
3713 desc = *slot;
3715 /* If the constant was already present, return its memory. */
3716 if (desc)
3717 return copy_rtx (desc->mem);
3719 /* Otherwise, create a new descriptor. */
3720 desc = ggc_alloc<constant_descriptor_rtx> ();
3721 *slot = desc;
3723 /* Align the location counter as required by EXP's data type. */
3724 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3726 tree type = lang_hooks.types.type_for_mode (mode, 0);
3727 if (type != NULL_TREE)
3728 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3730 pool->offset += (align / BITS_PER_UNIT) - 1;
3731 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3733 desc->next = NULL;
3734 desc->constant = copy_rtx (tmp.constant);
3735 desc->offset = pool->offset;
3736 desc->hash = hash;
3737 desc->mode = mode;
3738 desc->align = align;
3739 desc->labelno = const_labelno;
3740 desc->mark = 0;
3742 pool->offset += GET_MODE_SIZE (mode);
3743 if (pool->last)
3744 pool->last->next = desc;
3745 else
3746 pool->first = pool->last = desc;
3747 pool->last = desc;
3749 /* Create a string containing the label name, in LABEL. */
3750 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3751 ++const_labelno;
3753 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3754 the constants pool. */
3755 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3757 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3758 symbol = create_block_symbol (ggc_strdup (label),
3759 get_block_for_section (sect), -1);
3761 else
3762 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3763 desc->sym = symbol;
3764 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3765 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3766 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3768 /* Construct the MEM. */
3769 desc->mem = def = gen_const_mem (mode, symbol);
3770 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3771 set_mem_align (def, align);
3773 /* If we're dropping a label to the constant pool, make sure we
3774 don't delete it. */
3775 if (GET_CODE (x) == LABEL_REF)
3776 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3778 return copy_rtx (def);
3781 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3784 get_pool_constant (const_rtx addr)
3786 return SYMBOL_REF_CONSTANT (addr)->constant;
3789 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3790 and whether it has been output or not. */
3793 get_pool_constant_mark (rtx addr, bool *pmarked)
3795 struct constant_descriptor_rtx *desc;
3797 desc = SYMBOL_REF_CONSTANT (addr);
3798 *pmarked = (desc->mark != 0);
3799 return desc->constant;
3802 /* Similar, return the mode. */
3804 machine_mode
3805 get_pool_mode (const_rtx addr)
3807 return SYMBOL_REF_CONSTANT (addr)->mode;
3810 /* Return TRUE if and only if the constant pool has no entries. Note
3811 that even entries we might end up choosing not to emit are counted
3812 here, so there is the potential for missed optimizations. */
3814 bool
3815 constant_pool_empty_p (void)
3817 return crtl->varasm.pool->first == NULL;
3820 /* Worker function for output_constant_pool_1. Emit assembly for X
3821 in MODE with known alignment ALIGN. */
3823 static void
3824 output_constant_pool_2 (machine_mode mode, rtx x, unsigned int align)
3826 switch (GET_MODE_CLASS (mode))
3828 case MODE_FLOAT:
3829 case MODE_DECIMAL_FLOAT:
3831 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3832 assemble_real (*CONST_DOUBLE_REAL_VALUE (x), mode, align, false);
3833 break;
3836 case MODE_INT:
3837 case MODE_PARTIAL_INT:
3838 case MODE_FRACT:
3839 case MODE_UFRACT:
3840 case MODE_ACCUM:
3841 case MODE_UACCUM:
3842 case MODE_POINTER_BOUNDS:
3843 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3844 break;
3846 case MODE_VECTOR_FLOAT:
3847 case MODE_VECTOR_INT:
3848 case MODE_VECTOR_FRACT:
3849 case MODE_VECTOR_UFRACT:
3850 case MODE_VECTOR_ACCUM:
3851 case MODE_VECTOR_UACCUM:
3853 int i, units;
3854 machine_mode submode = GET_MODE_INNER (mode);
3855 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3857 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3858 units = CONST_VECTOR_NUNITS (x);
3860 for (i = 0; i < units; i++)
3862 rtx elt = CONST_VECTOR_ELT (x, i);
3863 output_constant_pool_2 (submode, elt, i ? subalign : align);
3866 break;
3868 default:
3869 gcc_unreachable ();
3873 /* Worker function for output_constant_pool. Emit constant DESC,
3874 giving it ALIGN bits of alignment. */
3876 static void
3877 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3878 unsigned int align)
3880 rtx x, tmp;
3882 x = desc->constant;
3884 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3885 whose CODE_LABEL has been deleted. This can occur if a jump table
3886 is eliminated by optimization. If so, write a constant of zero
3887 instead. Note that this can also happen by turning the
3888 CODE_LABEL into a NOTE. */
3889 /* ??? This seems completely and utterly wrong. Certainly it's
3890 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3891 functioning even with rtx_insn::deleted and friends. */
3893 tmp = x;
3894 switch (GET_CODE (tmp))
3896 case CONST:
3897 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3898 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
3899 break;
3900 tmp = XEXP (XEXP (tmp, 0), 0);
3901 /* FALLTHRU */
3903 case LABEL_REF:
3905 rtx_insn *insn = label_ref_label (tmp);
3906 gcc_assert (!insn->deleted ());
3907 gcc_assert (!NOTE_P (insn)
3908 || NOTE_KIND (insn) != NOTE_INSN_DELETED);
3909 break;
3912 default:
3913 break;
3916 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3917 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3918 align, desc->labelno, done);
3919 #endif
3921 assemble_align (align);
3923 /* Output the label. */
3924 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3926 /* Output the data.
3927 Pass actual alignment value while emitting string constant to asm code
3928 as function 'output_constant_pool_1' explicitly passes the alignment as 1
3929 assuming that the data is already aligned which prevents the generation
3930 of fix-up table entries. */
3931 output_constant_pool_2 (desc->mode, x, desc->align);
3933 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3934 sections have proper size. */
3935 if (align > GET_MODE_BITSIZE (desc->mode)
3936 && in_section
3937 && (in_section->common.flags & SECTION_MERGE))
3938 assemble_align (align);
3940 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3941 done:
3942 #endif
3943 return;
3946 /* Recompute the offsets of entries in POOL, and the overall size of
3947 POOL. Do this after calling mark_constant_pool to ensure that we
3948 are computing the offset values for the pool which we will actually
3949 emit. */
3951 static void
3952 recompute_pool_offsets (struct rtx_constant_pool *pool)
3954 struct constant_descriptor_rtx *desc;
3955 pool->offset = 0;
3957 for (desc = pool->first; desc ; desc = desc->next)
3958 if (desc->mark)
3960 /* Recalculate offset. */
3961 unsigned int align = desc->align;
3962 pool->offset += (align / BITS_PER_UNIT) - 1;
3963 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3964 desc->offset = pool->offset;
3965 pool->offset += GET_MODE_SIZE (desc->mode);
3969 /* Mark all constants that are referenced by SYMBOL_REFs in X.
3970 Emit referenced deferred strings. */
3972 static void
3973 mark_constants_in_pattern (rtx insn)
3975 subrtx_iterator::array_type array;
3976 FOR_EACH_SUBRTX (iter, array, PATTERN (insn), ALL)
3978 const_rtx x = *iter;
3979 if (GET_CODE (x) == SYMBOL_REF)
3981 if (CONSTANT_POOL_ADDRESS_P (x))
3983 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
3984 if (desc->mark == 0)
3986 desc->mark = 1;
3987 iter.substitute (desc->constant);
3990 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3992 tree decl = SYMBOL_REF_DECL (x);
3993 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
3995 n_deferred_constants--;
3996 output_constant_def_contents (CONST_CAST_RTX (x));
4003 /* Look through appropriate parts of INSN, marking all entries in the
4004 constant pool which are actually being used. Entries that are only
4005 referenced by other constants are also marked as used. Emit
4006 deferred strings that are used. */
4008 static void
4009 mark_constants (rtx_insn *insn)
4011 if (!INSN_P (insn))
4012 return;
4014 /* Insns may appear inside a SEQUENCE. Only check the patterns of
4015 insns, not any notes that may be attached. We don't want to mark
4016 a constant just because it happens to appear in a REG_EQUIV note. */
4017 if (rtx_sequence *seq = dyn_cast <rtx_sequence *> (PATTERN (insn)))
4019 int i, n = seq->len ();
4020 for (i = 0; i < n; ++i)
4022 rtx subinsn = seq->element (i);
4023 if (INSN_P (subinsn))
4024 mark_constants_in_pattern (subinsn);
4027 else
4028 mark_constants_in_pattern (insn);
4031 /* Look through the instructions for this function, and mark all the
4032 entries in POOL which are actually being used. Emit deferred constants
4033 which have indeed been used. */
4035 static void
4036 mark_constant_pool (void)
4038 rtx_insn *insn;
4040 if (!crtl->uses_const_pool && n_deferred_constants == 0)
4041 return;
4043 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4044 mark_constants (insn);
4047 /* Write all the constants in POOL. */
4049 static void
4050 output_constant_pool_contents (struct rtx_constant_pool *pool)
4052 struct constant_descriptor_rtx *desc;
4054 for (desc = pool->first; desc ; desc = desc->next)
4055 if (desc->mark)
4057 /* If the constant is part of an object_block, make sure that
4058 the constant has been positioned within its block, but do not
4059 write out its definition yet. output_object_blocks will do
4060 that later. */
4061 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
4062 && SYMBOL_REF_BLOCK (desc->sym))
4063 place_block_symbol (desc->sym);
4064 else
4066 switch_to_section (targetm.asm_out.select_rtx_section
4067 (desc->mode, desc->constant, desc->align));
4068 output_constant_pool_1 (desc, desc->align);
4073 /* Mark all constants that are used in the current function, then write
4074 out the function's private constant pool. */
4076 static void
4077 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
4078 tree fndecl ATTRIBUTE_UNUSED)
4080 struct rtx_constant_pool *pool = crtl->varasm.pool;
4082 /* It is possible for gcc to call force_const_mem and then to later
4083 discard the instructions which refer to the constant. In such a
4084 case we do not need to output the constant. */
4085 mark_constant_pool ();
4087 /* Having marked the constant pool entries we'll actually emit, we
4088 now need to rebuild the offset information, which may have become
4089 stale. */
4090 recompute_pool_offsets (pool);
4092 #ifdef ASM_OUTPUT_POOL_PROLOGUE
4093 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
4094 #endif
4096 output_constant_pool_contents (pool);
4098 #ifdef ASM_OUTPUT_POOL_EPILOGUE
4099 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
4100 #endif
4103 /* Write the contents of the shared constant pool. */
4105 void
4106 output_shared_constant_pool (void)
4108 output_constant_pool_contents (shared_constant_pool);
4111 /* Determine what kind of relocations EXP may need. */
4114 compute_reloc_for_constant (tree exp)
4116 int reloc = 0, reloc2;
4117 tree tem;
4119 switch (TREE_CODE (exp))
4121 case ADDR_EXPR:
4122 case FDESC_EXPR:
4123 /* Go inside any operations that get_inner_reference can handle and see
4124 if what's inside is a constant: no need to do anything here for
4125 addresses of variables or functions. */
4126 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4127 tem = TREE_OPERAND (tem, 0))
4130 if (TREE_CODE (tem) == MEM_REF
4131 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4133 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4134 break;
4137 if (!targetm.binds_local_p (tem))
4138 reloc |= 2;
4139 else
4140 reloc |= 1;
4141 break;
4143 case PLUS_EXPR:
4144 case POINTER_PLUS_EXPR:
4145 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4146 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4147 break;
4149 case MINUS_EXPR:
4150 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4151 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4152 /* The difference of two local labels is computable at link time. */
4153 if (reloc == 1 && reloc2 == 1)
4154 reloc = 0;
4155 else
4156 reloc |= reloc2;
4157 break;
4159 CASE_CONVERT:
4160 case VIEW_CONVERT_EXPR:
4161 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4162 break;
4164 case CONSTRUCTOR:
4166 unsigned HOST_WIDE_INT idx;
4167 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4168 if (tem != 0)
4169 reloc |= compute_reloc_for_constant (tem);
4171 break;
4173 default:
4174 break;
4176 return reloc;
4179 /* Find all the constants whose addresses are referenced inside of EXP,
4180 and make sure assembler code with a label has been output for each one.
4181 Indicate whether an ADDR_EXPR has been encountered. */
4183 static void
4184 output_addressed_constants (tree exp)
4186 tree tem;
4188 switch (TREE_CODE (exp))
4190 case ADDR_EXPR:
4191 case FDESC_EXPR:
4192 /* Go inside any operations that get_inner_reference can handle and see
4193 if what's inside is a constant: no need to do anything here for
4194 addresses of variables or functions. */
4195 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4196 tem = TREE_OPERAND (tem, 0))
4199 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4200 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4201 tem = DECL_INITIAL (tem);
4203 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4204 output_constant_def (tem, 0);
4206 if (TREE_CODE (tem) == MEM_REF)
4207 output_addressed_constants (TREE_OPERAND (tem, 0));
4208 break;
4210 case PLUS_EXPR:
4211 case POINTER_PLUS_EXPR:
4212 case MINUS_EXPR:
4213 output_addressed_constants (TREE_OPERAND (exp, 1));
4214 gcc_fallthrough ();
4216 CASE_CONVERT:
4217 case VIEW_CONVERT_EXPR:
4218 output_addressed_constants (TREE_OPERAND (exp, 0));
4219 break;
4221 case CONSTRUCTOR:
4223 unsigned HOST_WIDE_INT idx;
4224 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4225 if (tem != 0)
4226 output_addressed_constants (tem);
4228 break;
4230 default:
4231 break;
4235 /* Whether a constructor CTOR is a valid static constant initializer if all
4236 its elements are. This used to be internal to initializer_constant_valid_p
4237 and has been exposed to let other functions like categorize_ctor_elements
4238 evaluate the property while walking a constructor for other purposes. */
4240 bool
4241 constructor_static_from_elts_p (const_tree ctor)
4243 return (TREE_CONSTANT (ctor)
4244 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4245 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4246 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4249 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4250 tree *cache);
4252 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4253 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4254 which are valid when ENDTYPE is an integer of any size; in
4255 particular, this does not accept a pointer minus a constant. This
4256 returns null_pointer_node if the VALUE is an absolute constant
4257 which can be used to initialize a static variable. Otherwise it
4258 returns NULL. */
4260 static tree
4261 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4263 tree op0, op1;
4265 if (!INTEGRAL_TYPE_P (endtype))
4266 return NULL_TREE;
4268 op0 = TREE_OPERAND (value, 0);
4269 op1 = TREE_OPERAND (value, 1);
4271 /* Like STRIP_NOPS except allow the operand mode to widen. This
4272 works around a feature of fold that simplifies (int)(p1 - p2) to
4273 ((int)p1 - (int)p2) under the theory that the narrower operation
4274 is cheaper. */
4276 while (CONVERT_EXPR_P (op0)
4277 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4279 tree inner = TREE_OPERAND (op0, 0);
4280 if (inner == error_mark_node
4281 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4282 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
4283 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4284 break;
4285 op0 = inner;
4288 while (CONVERT_EXPR_P (op1)
4289 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4291 tree inner = TREE_OPERAND (op1, 0);
4292 if (inner == error_mark_node
4293 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4294 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
4295 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4296 break;
4297 op1 = inner;
4300 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4301 if (!op0)
4302 return NULL_TREE;
4304 op1 = initializer_constant_valid_p_1 (op1, endtype,
4305 cache ? cache + 2 : NULL);
4306 /* Both initializers must be known. */
4307 if (op1)
4309 if (op0 == op1
4310 && (op0 == null_pointer_node
4311 || TREE_CODE (value) == MINUS_EXPR))
4312 return null_pointer_node;
4314 /* Support differences between labels. */
4315 if (TREE_CODE (op0) == LABEL_DECL
4316 && TREE_CODE (op1) == LABEL_DECL)
4317 return null_pointer_node;
4319 if (TREE_CODE (op0) == STRING_CST
4320 && TREE_CODE (op1) == STRING_CST
4321 && operand_equal_p (op0, op1, 1))
4322 return null_pointer_node;
4325 return NULL_TREE;
4328 /* Helper function of initializer_constant_valid_p.
4329 Return nonzero if VALUE is a valid constant-valued expression
4330 for use in initializing a static variable; one that can be an
4331 element of a "constant" initializer.
4333 Return null_pointer_node if the value is absolute;
4334 if it is relocatable, return the variable that determines the relocation.
4335 We assume that VALUE has been folded as much as possible;
4336 therefore, we do not need to check for such things as
4337 arithmetic-combinations of integers.
4339 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4341 static tree
4342 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4344 tree ret;
4346 switch (TREE_CODE (value))
4348 case CONSTRUCTOR:
4349 if (constructor_static_from_elts_p (value))
4351 unsigned HOST_WIDE_INT idx;
4352 tree elt;
4353 bool absolute = true;
4355 if (cache && cache[0] == value)
4356 return cache[1];
4357 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4359 tree reloc;
4360 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4361 NULL);
4362 if (!reloc
4363 /* An absolute value is required with reverse SSO. */
4364 || (reloc != null_pointer_node
4365 && TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (value))
4366 && !AGGREGATE_TYPE_P (TREE_TYPE (elt))))
4368 if (cache)
4370 cache[0] = value;
4371 cache[1] = NULL_TREE;
4373 return NULL_TREE;
4375 if (reloc != null_pointer_node)
4376 absolute = false;
4378 /* For a non-absolute relocation, there is no single
4379 variable that can be "the variable that determines the
4380 relocation." */
4381 if (cache)
4383 cache[0] = value;
4384 cache[1] = absolute ? null_pointer_node : error_mark_node;
4386 return absolute ? null_pointer_node : error_mark_node;
4389 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4391 case INTEGER_CST:
4392 case VECTOR_CST:
4393 case REAL_CST:
4394 case FIXED_CST:
4395 case STRING_CST:
4396 case COMPLEX_CST:
4397 return null_pointer_node;
4399 case ADDR_EXPR:
4400 case FDESC_EXPR:
4402 tree op0 = staticp (TREE_OPERAND (value, 0));
4403 if (op0)
4405 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4406 to be a constant, this is old-skool offsetof-like nonsense. */
4407 if (TREE_CODE (op0) == INDIRECT_REF
4408 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4409 return null_pointer_node;
4410 /* Taking the address of a nested function involves a trampoline,
4411 unless we don't need or want one. */
4412 if (TREE_CODE (op0) == FUNCTION_DECL
4413 && DECL_STATIC_CHAIN (op0)
4414 && !TREE_NO_TRAMPOLINE (value))
4415 return NULL_TREE;
4416 /* "&{...}" requires a temporary to hold the constructed
4417 object. */
4418 if (TREE_CODE (op0) == CONSTRUCTOR)
4419 return NULL_TREE;
4421 return op0;
4424 case NON_LVALUE_EXPR:
4425 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4426 endtype, cache);
4428 case VIEW_CONVERT_EXPR:
4430 tree src = TREE_OPERAND (value, 0);
4431 tree src_type = TREE_TYPE (src);
4432 tree dest_type = TREE_TYPE (value);
4434 /* Allow view-conversions from aggregate to non-aggregate type only
4435 if the bit pattern is fully preserved afterwards; otherwise, the
4436 RTL expander won't be able to apply a subsequent transformation
4437 to the underlying constructor. */
4438 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4440 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4441 return initializer_constant_valid_p_1 (src, endtype, cache);
4442 else
4443 return NULL_TREE;
4446 /* Allow all other kinds of view-conversion. */
4447 return initializer_constant_valid_p_1 (src, endtype, cache);
4450 CASE_CONVERT:
4452 tree src = TREE_OPERAND (value, 0);
4453 tree src_type = TREE_TYPE (src);
4454 tree dest_type = TREE_TYPE (value);
4456 /* Allow conversions between pointer types, floating-point
4457 types, and offset types. */
4458 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4459 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4460 || (TREE_CODE (dest_type) == OFFSET_TYPE
4461 && TREE_CODE (src_type) == OFFSET_TYPE))
4462 return initializer_constant_valid_p_1 (src, endtype, cache);
4464 /* Allow length-preserving conversions between integer types. */
4465 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4466 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4467 return initializer_constant_valid_p_1 (src, endtype, cache);
4469 /* Allow conversions between other integer types only if
4470 explicit value. Don't allow sign-extension to a type larger
4471 than word and pointer, there aren't relocations that would
4472 allow to sign extend it to a wider type. */
4473 if (INTEGRAL_TYPE_P (dest_type)
4474 && INTEGRAL_TYPE_P (src_type)
4475 && (TYPE_UNSIGNED (src_type)
4476 || TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type)
4477 || TYPE_PRECISION (dest_type) <= BITS_PER_WORD
4478 || TYPE_PRECISION (dest_type) <= POINTER_SIZE))
4480 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4481 if (inner == null_pointer_node)
4482 return null_pointer_node;
4483 break;
4486 /* Allow (int) &foo provided int is as wide as a pointer. */
4487 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4488 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4489 return initializer_constant_valid_p_1 (src, endtype, cache);
4491 /* Likewise conversions from int to pointers, but also allow
4492 conversions from 0. */
4493 if ((POINTER_TYPE_P (dest_type)
4494 || TREE_CODE (dest_type) == OFFSET_TYPE)
4495 && INTEGRAL_TYPE_P (src_type))
4497 if (TREE_CODE (src) == INTEGER_CST
4498 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4499 return null_pointer_node;
4500 if (integer_zerop (src))
4501 return null_pointer_node;
4502 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4503 return initializer_constant_valid_p_1 (src, endtype, cache);
4506 /* Allow conversions to struct or union types if the value
4507 inside is okay. */
4508 if (TREE_CODE (dest_type) == RECORD_TYPE
4509 || TREE_CODE (dest_type) == UNION_TYPE)
4510 return initializer_constant_valid_p_1 (src, endtype, cache);
4512 break;
4514 case POINTER_PLUS_EXPR:
4515 case PLUS_EXPR:
4516 /* Any valid floating-point constants will have been folded by now;
4517 with -frounding-math we hit this with addition of two constants. */
4518 if (TREE_CODE (endtype) == REAL_TYPE)
4519 return NULL_TREE;
4520 if (cache && cache[0] == value)
4521 return cache[1];
4522 if (! INTEGRAL_TYPE_P (endtype)
4523 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4525 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4526 tree valid0
4527 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4528 endtype, ncache);
4529 tree valid1
4530 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4531 endtype, ncache + 2);
4532 /* If either term is absolute, use the other term's relocation. */
4533 if (valid0 == null_pointer_node)
4534 ret = valid1;
4535 else if (valid1 == null_pointer_node)
4536 ret = valid0;
4537 /* Support narrowing pointer differences. */
4538 else
4539 ret = narrowing_initializer_constant_valid_p (value, endtype,
4540 ncache);
4542 else
4543 /* Support narrowing pointer differences. */
4544 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4545 if (cache)
4547 cache[0] = value;
4548 cache[1] = ret;
4550 return ret;
4552 case MINUS_EXPR:
4553 if (TREE_CODE (endtype) == REAL_TYPE)
4554 return NULL_TREE;
4555 if (cache && cache[0] == value)
4556 return cache[1];
4557 if (! INTEGRAL_TYPE_P (endtype)
4558 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4560 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4561 tree valid0
4562 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4563 endtype, ncache);
4564 tree valid1
4565 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4566 endtype, ncache + 2);
4567 /* Win if second argument is absolute. */
4568 if (valid1 == null_pointer_node)
4569 ret = valid0;
4570 /* Win if both arguments have the same relocation.
4571 Then the value is absolute. */
4572 else if (valid0 == valid1 && valid0 != 0)
4573 ret = null_pointer_node;
4574 /* Since GCC guarantees that string constants are unique in the
4575 generated code, a subtraction between two copies of the same
4576 constant string is absolute. */
4577 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4578 && valid1 && TREE_CODE (valid1) == STRING_CST
4579 && operand_equal_p (valid0, valid1, 1))
4580 ret = null_pointer_node;
4581 /* Support narrowing differences. */
4582 else
4583 ret = narrowing_initializer_constant_valid_p (value, endtype,
4584 ncache);
4586 else
4587 /* Support narrowing differences. */
4588 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4589 if (cache)
4591 cache[0] = value;
4592 cache[1] = ret;
4594 return ret;
4596 default:
4597 break;
4600 return NULL_TREE;
4603 /* Return nonzero if VALUE is a valid constant-valued expression
4604 for use in initializing a static variable; one that can be an
4605 element of a "constant" initializer.
4607 Return null_pointer_node if the value is absolute;
4608 if it is relocatable, return the variable that determines the relocation.
4609 We assume that VALUE has been folded as much as possible;
4610 therefore, we do not need to check for such things as
4611 arithmetic-combinations of integers. */
4612 tree
4613 initializer_constant_valid_p (tree value, tree endtype, bool reverse)
4615 tree reloc = initializer_constant_valid_p_1 (value, endtype, NULL);
4617 /* An absolute value is required with reverse storage order. */
4618 if (reloc
4619 && reloc != null_pointer_node
4620 && reverse
4621 && !AGGREGATE_TYPE_P (endtype)
4622 && !VECTOR_TYPE_P (endtype))
4623 reloc = NULL_TREE;
4625 return reloc;
4628 /* Return true if VALUE is a valid constant-valued expression
4629 for use in initializing a static bit-field; one that can be
4630 an element of a "constant" initializer. */
4632 bool
4633 initializer_constant_valid_for_bitfield_p (tree value)
4635 /* For bitfields we support integer constants or possibly nested aggregates
4636 of such. */
4637 switch (TREE_CODE (value))
4639 case CONSTRUCTOR:
4641 unsigned HOST_WIDE_INT idx;
4642 tree elt;
4644 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4645 if (!initializer_constant_valid_for_bitfield_p (elt))
4646 return false;
4647 return true;
4650 case INTEGER_CST:
4651 case REAL_CST:
4652 return true;
4654 case VIEW_CONVERT_EXPR:
4655 case NON_LVALUE_EXPR:
4656 return
4657 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4659 default:
4660 break;
4663 return false;
4666 /* output_constructor outer state of relevance in recursive calls, typically
4667 for nested aggregate bitfields. */
4669 struct oc_outer_state {
4670 unsigned int bit_offset; /* current position in ... */
4671 int byte; /* ... the outer byte buffer. */
4674 static unsigned HOST_WIDE_INT
4675 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int, bool,
4676 oc_outer_state *);
4678 /* Output assembler code for constant EXP, with no label.
4679 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4680 Assumes output_addressed_constants has been done on EXP already.
4682 Generate at least SIZE bytes of assembler data, padding at the end
4683 with zeros if necessary. SIZE must always be specified. The returned
4684 value is the actual number of bytes of assembler data generated, which
4685 may be bigger than SIZE if the object contains a variable length field.
4687 SIZE is important for structure constructors,
4688 since trailing members may have been omitted from the constructor.
4689 It is also important for initialization of arrays from string constants
4690 since the full length of the string constant might not be wanted.
4691 It is also needed for initialization of unions, where the initializer's
4692 type is just one member, and that may not be as long as the union.
4694 There a case in which we would fail to output exactly SIZE bytes:
4695 for a structure constructor that wants to produce more than SIZE bytes.
4696 But such constructors will never be generated for any possible input.
4698 ALIGN is the alignment of the data in bits.
4700 If REVERSE is true, EXP is output in reverse storage order. */
4702 static unsigned HOST_WIDE_INT
4703 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align,
4704 bool reverse)
4706 enum tree_code code;
4707 unsigned HOST_WIDE_INT thissize;
4708 rtx cst;
4710 if (size == 0 || flag_syntax_only)
4711 return size;
4713 /* See if we're trying to initialize a pointer in a non-default mode
4714 to the address of some declaration somewhere. If the target says
4715 the mode is valid for pointers, assume the target has a way of
4716 resolving it. */
4717 if (TREE_CODE (exp) == NOP_EXPR
4718 && POINTER_TYPE_P (TREE_TYPE (exp))
4719 && targetm.addr_space.valid_pointer_mode
4720 (TYPE_MODE (TREE_TYPE (exp)),
4721 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4723 tree saved_type = TREE_TYPE (exp);
4725 /* Peel off any intermediate conversions-to-pointer for valid
4726 pointer modes. */
4727 while (TREE_CODE (exp) == NOP_EXPR
4728 && POINTER_TYPE_P (TREE_TYPE (exp))
4729 && targetm.addr_space.valid_pointer_mode
4730 (TYPE_MODE (TREE_TYPE (exp)),
4731 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4732 exp = TREE_OPERAND (exp, 0);
4734 /* If what we're left with is the address of something, we can
4735 convert the address to the final type and output it that
4736 way. */
4737 if (TREE_CODE (exp) == ADDR_EXPR)
4738 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4739 /* Likewise for constant ints. */
4740 else if (TREE_CODE (exp) == INTEGER_CST)
4741 exp = fold_convert (saved_type, exp);
4745 /* Eliminate any conversions since we'll be outputting the underlying
4746 constant. */
4747 while (CONVERT_EXPR_P (exp)
4748 || TREE_CODE (exp) == NON_LVALUE_EXPR
4749 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4751 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4752 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4754 /* Make sure eliminating the conversion is really a no-op, except with
4755 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4756 union types to allow for Ada unchecked unions. */
4757 if (type_size > op_size
4758 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4759 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4760 /* Keep the conversion. */
4761 break;
4762 else
4763 exp = TREE_OPERAND (exp, 0);
4766 code = TREE_CODE (TREE_TYPE (exp));
4767 thissize = int_size_in_bytes (TREE_TYPE (exp));
4769 /* Allow a constructor with no elements for any data type.
4770 This means to fill the space with zeros. */
4771 if (TREE_CODE (exp) == CONSTRUCTOR
4772 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4774 assemble_zeros (size);
4775 return size;
4778 if (TREE_CODE (exp) == FDESC_EXPR)
4780 #ifdef ASM_OUTPUT_FDESC
4781 HOST_WIDE_INT part = tree_to_shwi (TREE_OPERAND (exp, 1));
4782 tree decl = TREE_OPERAND (exp, 0);
4783 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4784 #else
4785 gcc_unreachable ();
4786 #endif
4787 return size;
4790 /* Now output the underlying data. If we've handling the padding, return.
4791 Otherwise, break and ensure SIZE is the size written. */
4792 switch (code)
4794 case BOOLEAN_TYPE:
4795 case INTEGER_TYPE:
4796 case ENUMERAL_TYPE:
4797 case POINTER_TYPE:
4798 case REFERENCE_TYPE:
4799 case OFFSET_TYPE:
4800 case FIXED_POINT_TYPE:
4801 case POINTER_BOUNDS_TYPE:
4802 case NULLPTR_TYPE:
4803 cst = expand_expr (exp, NULL_RTX, VOIDmode, EXPAND_INITIALIZER);
4804 if (reverse)
4805 cst = flip_storage_order (TYPE_MODE (TREE_TYPE (exp)), cst);
4806 if (!assemble_integer (cst, MIN (size, thissize), align, 0))
4807 error ("initializer for integer/fixed-point value is too complicated");
4808 break;
4810 case REAL_TYPE:
4811 if (TREE_CODE (exp) != REAL_CST)
4812 error ("initializer for floating value is not a floating constant");
4813 else
4814 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)),
4815 align, reverse);
4816 break;
4818 case COMPLEX_TYPE:
4819 output_constant (TREE_REALPART (exp), thissize / 2, align, reverse);
4820 output_constant (TREE_IMAGPART (exp), thissize / 2,
4821 min_align (align, BITS_PER_UNIT * (thissize / 2)),
4822 reverse);
4823 break;
4825 case ARRAY_TYPE:
4826 case VECTOR_TYPE:
4827 switch (TREE_CODE (exp))
4829 case CONSTRUCTOR:
4830 return output_constructor (exp, size, align, reverse, NULL);
4831 case STRING_CST:
4832 thissize
4833 = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4834 assemble_string (TREE_STRING_POINTER (exp), thissize);
4835 break;
4836 case VECTOR_CST:
4838 machine_mode inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4839 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4840 int elt_size = GET_MODE_SIZE (inner);
4841 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align,
4842 reverse);
4843 thissize = elt_size;
4844 for (unsigned int i = 1; i < VECTOR_CST_NELTS (exp); i++)
4846 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign,
4847 reverse);
4848 thissize += elt_size;
4850 break;
4852 default:
4853 gcc_unreachable ();
4855 break;
4857 case RECORD_TYPE:
4858 case UNION_TYPE:
4859 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4860 return output_constructor (exp, size, align, reverse, NULL);
4862 case ERROR_MARK:
4863 return 0;
4865 default:
4866 gcc_unreachable ();
4869 if (size > thissize)
4870 assemble_zeros (size - thissize);
4872 return size;
4875 /* Subroutine of output_constructor, used for computing the size of
4876 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4877 type with an unspecified upper bound. */
4879 static unsigned HOST_WIDE_INT
4880 array_size_for_constructor (tree val)
4882 tree max_index;
4883 unsigned HOST_WIDE_INT cnt;
4884 tree index, value, tmp;
4885 offset_int i;
4887 /* This code used to attempt to handle string constants that are not
4888 arrays of single-bytes, but nothing else does, so there's no point in
4889 doing it here. */
4890 if (TREE_CODE (val) == STRING_CST)
4891 return TREE_STRING_LENGTH (val);
4893 max_index = NULL_TREE;
4894 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
4896 if (TREE_CODE (index) == RANGE_EXPR)
4897 index = TREE_OPERAND (index, 1);
4898 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
4899 max_index = index;
4902 if (max_index == NULL_TREE)
4903 return 0;
4905 /* Compute the total number of array elements. */
4906 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
4907 i = wi::to_offset (max_index) - wi::to_offset (tmp) + 1;
4909 /* Multiply by the array element unit size to find number of bytes. */
4910 i *= wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
4912 gcc_assert (wi::fits_uhwi_p (i));
4913 return i.to_uhwi ();
4916 /* Other datastructures + helpers for output_constructor. */
4918 /* output_constructor local state to support interaction with helpers. */
4920 struct oc_local_state {
4922 /* Received arguments. */
4923 tree exp; /* Constructor expression. */
4924 tree type; /* Type of constructor expression. */
4925 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */
4926 unsigned int align; /* Known initial alignment. */
4927 tree min_index; /* Lower bound if specified for an array. */
4929 /* Output processing state. */
4930 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */
4931 int byte; /* Part of a bitfield byte yet to be output. */
4932 int last_relative_index; /* Implicit or explicit index of the last
4933 array element output within a bitfield. */
4934 bool byte_buffer_in_use; /* Whether BYTE is in use. */
4935 bool reverse; /* Whether reverse storage order is in use. */
4937 /* Current element. */
4938 tree field; /* Current field decl in a record. */
4939 tree val; /* Current element value. */
4940 tree index; /* Current element index. */
4944 /* Helper for output_constructor. From the current LOCAL state, output a
4945 RANGE_EXPR element. */
4947 static void
4948 output_constructor_array_range (oc_local_state *local)
4950 unsigned HOST_WIDE_INT fieldsize
4951 = int_size_in_bytes (TREE_TYPE (local->type));
4953 HOST_WIDE_INT lo_index
4954 = tree_to_shwi (TREE_OPERAND (local->index, 0));
4955 HOST_WIDE_INT hi_index
4956 = tree_to_shwi (TREE_OPERAND (local->index, 1));
4957 HOST_WIDE_INT index;
4959 unsigned int align2
4960 = min_align (local->align, fieldsize * BITS_PER_UNIT);
4962 for (index = lo_index; index <= hi_index; index++)
4964 /* Output the element's initial value. */
4965 if (local->val == NULL_TREE)
4966 assemble_zeros (fieldsize);
4967 else
4968 fieldsize
4969 = output_constant (local->val, fieldsize, align2, local->reverse);
4971 /* Count its size. */
4972 local->total_bytes += fieldsize;
4976 /* Helper for output_constructor. From the current LOCAL state, output a
4977 field element that is not true bitfield or part of an outer one. */
4979 static void
4980 output_constructor_regular_field (oc_local_state *local)
4982 /* Field size and position. Since this structure is static, we know the
4983 positions are constant. */
4984 unsigned HOST_WIDE_INT fieldsize;
4985 HOST_WIDE_INT fieldpos;
4987 unsigned int align2;
4989 /* Output any buffered-up bit-fields preceding this element. */
4990 if (local->byte_buffer_in_use)
4992 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4993 local->total_bytes++;
4994 local->byte_buffer_in_use = false;
4997 if (local->index != NULL_TREE)
4999 /* Perform the index calculation in modulo arithmetic but
5000 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
5001 but we are using an unsigned sizetype. */
5002 unsigned prec = TYPE_PRECISION (sizetype);
5003 offset_int idx = wi::sext (wi::to_offset (local->index)
5004 - wi::to_offset (local->min_index), prec);
5005 fieldpos = (idx * wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (local->val))))
5006 .to_short_addr ();
5008 else if (local->field != NULL_TREE)
5009 fieldpos = int_byte_position (local->field);
5010 else
5011 fieldpos = 0;
5013 /* Advance to offset of this element.
5014 Note no alignment needed in an array, since that is guaranteed
5015 if each element has the proper size. */
5016 if (local->field != NULL_TREE || local->index != NULL_TREE)
5018 if (fieldpos > local->total_bytes)
5020 assemble_zeros (fieldpos - local->total_bytes);
5021 local->total_bytes = fieldpos;
5023 else
5024 /* Must not go backwards. */
5025 gcc_assert (fieldpos == local->total_bytes);
5028 /* Find the alignment of this element. */
5029 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
5031 /* Determine size this element should occupy. */
5032 if (local->field)
5034 fieldsize = 0;
5036 /* If this is an array with an unspecified upper bound,
5037 the initializer determines the size. */
5038 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
5039 but we cannot do this until the deprecated support for
5040 initializing zero-length array members is removed. */
5041 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
5042 && (!TYPE_DOMAIN (TREE_TYPE (local->field))
5043 || !TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field)))))
5045 fieldsize = array_size_for_constructor (local->val);
5046 /* Given a non-empty initialization, this field had better
5047 be last. Given a flexible array member, the next field
5048 on the chain is a TYPE_DECL of the enclosing struct. */
5049 const_tree next = DECL_CHAIN (local->field);
5050 gcc_assert (!fieldsize || !next || TREE_CODE (next) != FIELD_DECL);
5052 else
5053 fieldsize = tree_to_uhwi (DECL_SIZE_UNIT (local->field));
5055 else
5056 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
5058 /* Output the element's initial value. */
5059 if (local->val == NULL_TREE)
5060 assemble_zeros (fieldsize);
5061 else
5062 fieldsize
5063 = output_constant (local->val, fieldsize, align2, local->reverse);
5065 /* Count its size. */
5066 local->total_bytes += fieldsize;
5069 /* Helper for output_constructor. From the LOCAL state, output an element
5070 that is a true bitfield or part of an outer one. BIT_OFFSET is the offset
5071 from the start of a possibly ongoing outer byte buffer. */
5073 static void
5074 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
5076 /* Bit size of this element. */
5077 HOST_WIDE_INT ebitsize
5078 = (local->field
5079 ? tree_to_uhwi (DECL_SIZE (local->field))
5080 : tree_to_uhwi (TYPE_SIZE (TREE_TYPE (local->type))));
5082 /* Relative index of this element if this is an array component. */
5083 HOST_WIDE_INT relative_index
5084 = (!local->field
5085 ? (local->index
5086 ? (tree_to_shwi (local->index)
5087 - tree_to_shwi (local->min_index))
5088 : local->last_relative_index + 1)
5089 : 0);
5091 /* Bit position of this element from the start of the containing
5092 constructor. */
5093 HOST_WIDE_INT constructor_relative_ebitpos
5094 = (local->field
5095 ? int_bit_position (local->field)
5096 : ebitsize * relative_index);
5098 /* Bit position of this element from the start of a possibly ongoing
5099 outer byte buffer. */
5100 HOST_WIDE_INT byte_relative_ebitpos
5101 = bit_offset + constructor_relative_ebitpos;
5103 /* From the start of a possibly ongoing outer byte buffer, offsets to
5104 the first bit of this element and to the first bit past the end of
5105 this element. */
5106 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
5107 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
5109 local->last_relative_index = relative_index;
5111 if (local->val == NULL_TREE)
5112 local->val = integer_zero_node;
5114 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
5115 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
5116 local->val = TREE_OPERAND (local->val, 0);
5118 if (TREE_CODE (local->val) != INTEGER_CST
5119 && TREE_CODE (local->val) != CONSTRUCTOR)
5121 error ("invalid initial value for member %qE", DECL_NAME (local->field));
5122 return;
5125 /* If this field does not start in this (or next) byte, skip some bytes. */
5126 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5128 /* Output remnant of any bit field in previous bytes. */
5129 if (local->byte_buffer_in_use)
5131 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5132 local->total_bytes++;
5133 local->byte_buffer_in_use = false;
5136 /* If still not at proper byte, advance to there. */
5137 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5139 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
5140 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
5141 local->total_bytes = next_offset / BITS_PER_UNIT;
5145 /* Set up the buffer if necessary. */
5146 if (!local->byte_buffer_in_use)
5148 local->byte = 0;
5149 if (ebitsize > 0)
5150 local->byte_buffer_in_use = true;
5153 /* If this is nested constructor, recurse passing the bit offset and the
5154 pending data, then retrieve the new pending data afterwards. */
5155 if (TREE_CODE (local->val) == CONSTRUCTOR)
5157 oc_outer_state temp_state;
5158 temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5159 temp_state.byte = local->byte;
5160 local->total_bytes
5161 += output_constructor (local->val, 0, 0, local->reverse, &temp_state);
5162 local->byte = temp_state.byte;
5163 return;
5166 /* Otherwise, we must split the element into pieces that fall within
5167 separate bytes, and combine each byte with previous or following
5168 bit-fields. */
5169 while (next_offset < end_offset)
5171 int this_time;
5172 int shift;
5173 HOST_WIDE_INT value;
5174 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5175 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5177 /* Advance from byte to byte within this element when necessary. */
5178 while (next_byte != local->total_bytes)
5180 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5181 local->total_bytes++;
5182 local->byte = 0;
5185 /* Number of bits we can process at once (all part of the same byte). */
5186 this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5187 if (local->reverse ? !BYTES_BIG_ENDIAN : BYTES_BIG_ENDIAN)
5189 /* For big-endian data, take the most significant bits (of the
5190 bits that are significant) first and put them into bytes from
5191 the most significant end. */
5192 shift = end_offset - next_offset - this_time;
5194 /* Don't try to take a bunch of bits that cross
5195 the word boundary in the INTEGER_CST. We can
5196 only select bits from one element. */
5197 if ((shift / HOST_BITS_PER_WIDE_INT)
5198 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5200 const int end = shift + this_time - 1;
5201 shift = end & -HOST_BITS_PER_WIDE_INT;
5202 this_time = end - shift + 1;
5205 /* Now get the bits from the appropriate constant word. */
5206 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5207 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5209 /* Get the result. This works only when:
5210 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5211 local->byte |= (((value >> shift)
5212 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5213 << (BITS_PER_UNIT - this_time - next_bit));
5215 else
5217 /* On little-endian machines, take the least significant bits of
5218 the value first and pack them starting at the least significant
5219 bits of the bytes. */
5220 shift = next_offset - byte_relative_ebitpos;
5222 /* Don't try to take a bunch of bits that cross
5223 the word boundary in the INTEGER_CST. We can
5224 only select bits from one element. */
5225 if ((shift / HOST_BITS_PER_WIDE_INT)
5226 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5227 this_time
5228 = HOST_BITS_PER_WIDE_INT - (shift & (HOST_BITS_PER_WIDE_INT - 1));
5230 /* Now get the bits from the appropriate constant word. */
5231 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5232 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5234 /* Get the result. This works only when:
5235 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5236 local->byte |= (((value >> shift)
5237 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5238 << next_bit);
5241 next_offset += this_time;
5242 local->byte_buffer_in_use = true;
5246 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5247 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5248 caller output state of relevance in recursive invocations. */
5250 static unsigned HOST_WIDE_INT
5251 output_constructor (tree exp, unsigned HOST_WIDE_INT size, unsigned int align,
5252 bool reverse, oc_outer_state *outer)
5254 unsigned HOST_WIDE_INT cnt;
5255 constructor_elt *ce;
5256 oc_local_state local;
5258 /* Setup our local state to communicate with helpers. */
5259 local.exp = exp;
5260 local.type = TREE_TYPE (exp);
5261 local.size = size;
5262 local.align = align;
5263 if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5264 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5265 else
5266 local.min_index = integer_zero_node;
5268 local.total_bytes = 0;
5269 local.byte_buffer_in_use = outer != NULL;
5270 local.byte = outer ? outer->byte : 0;
5271 local.last_relative_index = -1;
5272 /* The storage order is specified for every aggregate type. */
5273 if (AGGREGATE_TYPE_P (local.type))
5274 local.reverse = TYPE_REVERSE_STORAGE_ORDER (local.type);
5275 else
5276 local.reverse = reverse;
5278 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5280 /* As CE goes through the elements of the constant, FIELD goes through the
5281 structure fields if the constant is a structure. If the constant is a
5282 union, we override this by getting the field from the TREE_LIST element.
5283 But the constant could also be an array. Then FIELD is zero.
5285 There is always a maximum of one element in the chain LINK for unions
5286 (even if the initializer in a source program incorrectly contains
5287 more one). */
5289 if (TREE_CODE (local.type) == RECORD_TYPE)
5290 local.field = TYPE_FIELDS (local.type);
5291 else
5292 local.field = NULL_TREE;
5294 for (cnt = 0;
5295 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5296 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5298 local.val = ce->value;
5299 local.index = NULL_TREE;
5301 /* The element in a union constructor specifies the proper field
5302 or index. */
5303 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5304 local.field = ce->index;
5306 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5307 local.index = ce->index;
5309 if (local.field && flag_verbose_asm)
5310 fprintf (asm_out_file, "%s %s:\n",
5311 ASM_COMMENT_START,
5312 DECL_NAME (local.field)
5313 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5314 : "<anonymous>");
5316 /* Eliminate the marker that makes a cast not be an lvalue. */
5317 if (local.val != NULL_TREE)
5318 STRIP_NOPS (local.val);
5320 /* Output the current element, using the appropriate helper ... */
5322 /* For an array slice not part of an outer bitfield. */
5323 if (!outer
5324 && local.index != NULL_TREE
5325 && TREE_CODE (local.index) == RANGE_EXPR)
5326 output_constructor_array_range (&local);
5328 /* For a field that is neither a true bitfield nor part of an outer one,
5329 known to be at least byte aligned and multiple-of-bytes long. */
5330 else if (!outer
5331 && (local.field == NULL_TREE
5332 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5333 output_constructor_regular_field (&local);
5335 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5336 supported for scalar fields, so we may need to convert first. */
5337 else
5339 if (TREE_CODE (local.val) == REAL_CST)
5340 local.val
5341 = fold_unary (VIEW_CONVERT_EXPR,
5342 build_nonstandard_integer_type
5343 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5344 local.val);
5345 output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5349 /* If we are not at toplevel, save the pending data for our caller.
5350 Otherwise output the pending data and padding zeros as needed. */
5351 if (outer)
5352 outer->byte = local.byte;
5353 else
5355 if (local.byte_buffer_in_use)
5357 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5358 local.total_bytes++;
5361 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5363 assemble_zeros (local.size - local.total_bytes);
5364 local.total_bytes = local.size;
5368 return local.total_bytes;
5371 /* Mark DECL as weak. */
5373 static void
5374 mark_weak (tree decl)
5376 if (DECL_WEAK (decl))
5377 return;
5379 struct symtab_node *n = symtab_node::get (decl);
5380 if (n && n->refuse_visibility_changes)
5381 error ("%+qD declared weak after being used", decl);
5382 DECL_WEAK (decl) = 1;
5384 if (DECL_RTL_SET_P (decl)
5385 && MEM_P (DECL_RTL (decl))
5386 && XEXP (DECL_RTL (decl), 0)
5387 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5388 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5391 /* Merge weak status between NEWDECL and OLDDECL. */
5393 void
5394 merge_weak (tree newdecl, tree olddecl)
5396 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5398 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5400 tree *pwd;
5401 /* We put the NEWDECL on the weak_decls list at some point
5402 and OLDDECL as well. Keep just OLDDECL on the list. */
5403 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5404 if (TREE_VALUE (*pwd) == newdecl)
5406 *pwd = TREE_CHAIN (*pwd);
5407 break;
5410 return;
5413 if (DECL_WEAK (newdecl))
5415 tree wd;
5417 /* NEWDECL is weak, but OLDDECL is not. */
5419 /* If we already output the OLDDECL, we're in trouble; we can't
5420 go back and make it weak. This should never happen in
5421 unit-at-a-time compilation. */
5422 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5424 /* If we've already generated rtl referencing OLDDECL, we may
5425 have done so in a way that will not function properly with
5426 a weak symbol. Again in unit-at-a-time this should be
5427 impossible. */
5428 gcc_assert (!TREE_USED (olddecl)
5429 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5431 /* PR 49899: You cannot convert a static function into a weak, public function. */
5432 if (! TREE_PUBLIC (olddecl) && TREE_PUBLIC (newdecl))
5433 error ("weak declaration of %q+D being applied to a already "
5434 "existing, static definition", newdecl);
5436 if (TARGET_SUPPORTS_WEAK)
5438 /* We put the NEWDECL on the weak_decls list at some point.
5439 Replace it with the OLDDECL. */
5440 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5441 if (TREE_VALUE (wd) == newdecl)
5443 TREE_VALUE (wd) = olddecl;
5444 break;
5446 /* We may not find the entry on the list. If NEWDECL is a
5447 weak alias, then we will have already called
5448 globalize_decl to remove the entry; in that case, we do
5449 not need to do anything. */
5452 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5453 mark_weak (olddecl);
5455 else
5456 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5457 weak. Just update NEWDECL to indicate that it's weak too. */
5458 mark_weak (newdecl);
5461 /* Declare DECL to be a weak symbol. */
5463 void
5464 declare_weak (tree decl)
5466 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5467 if (! TREE_PUBLIC (decl))
5469 error ("weak declaration of %q+D must be public", decl);
5470 return;
5472 else if (!TARGET_SUPPORTS_WEAK)
5473 warning (0, "weak declaration of %q+D not supported", decl);
5475 mark_weak (decl);
5476 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5477 DECL_ATTRIBUTES (decl)
5478 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5481 static void
5482 weak_finish_1 (tree decl)
5484 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5485 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5486 #endif
5488 if (! TREE_USED (decl))
5489 return;
5491 #ifdef ASM_WEAKEN_DECL
5492 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5493 #else
5494 #ifdef ASM_WEAKEN_LABEL
5495 ASM_WEAKEN_LABEL (asm_out_file, name);
5496 #else
5497 #ifdef ASM_OUTPUT_WEAK_ALIAS
5499 static bool warn_once = 0;
5500 if (! warn_once)
5502 warning (0, "only weak aliases are supported in this configuration");
5503 warn_once = 1;
5505 return;
5507 #endif
5508 #endif
5509 #endif
5512 /* Fiven an assembly name, find the decl it is associated with. */
5513 static tree
5514 find_decl (tree target)
5516 symtab_node *node = symtab_node::get_for_asmname (target);
5517 if (node)
5518 return node->decl;
5519 return NULL_TREE;
5522 /* This TREE_LIST contains weakref targets. */
5524 static GTY(()) tree weakref_targets;
5526 /* Emit any pending weak declarations. */
5528 void
5529 weak_finish (void)
5531 tree t;
5533 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5535 tree alias_decl = TREE_PURPOSE (t);
5536 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5538 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5539 /* Remove alias_decl from the weak list, but leave entries for
5540 the target alone. */
5541 target = NULL_TREE;
5542 #ifndef ASM_OUTPUT_WEAKREF
5543 else if (! TREE_SYMBOL_REFERENCED (target))
5545 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5546 defined, otherwise we and weak_finish_1 would use
5547 different macros. */
5548 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5549 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5550 # else
5551 tree decl = find_decl (target);
5553 if (! decl)
5555 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5556 TREE_CODE (alias_decl), target,
5557 TREE_TYPE (alias_decl));
5559 DECL_EXTERNAL (decl) = 1;
5560 TREE_PUBLIC (decl) = 1;
5561 DECL_ARTIFICIAL (decl) = 1;
5562 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5563 TREE_USED (decl) = 1;
5566 weak_finish_1 (decl);
5567 # endif
5569 #endif
5572 tree *p;
5573 tree t2;
5575 /* Remove the alias and the target from the pending weak list
5576 so that we do not emit any .weak directives for the former,
5577 nor multiple .weak directives for the latter. */
5578 for (p = &weak_decls; (t2 = *p) ; )
5580 if (TREE_VALUE (t2) == alias_decl
5581 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5582 *p = TREE_CHAIN (t2);
5583 else
5584 p = &TREE_CHAIN (t2);
5587 /* Remove other weakrefs to the same target, to speed things up. */
5588 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5590 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5591 *p = TREE_CHAIN (t2);
5592 else
5593 p = &TREE_CHAIN (t2);
5598 for (t = weak_decls; t; t = TREE_CHAIN (t))
5600 tree decl = TREE_VALUE (t);
5602 weak_finish_1 (decl);
5606 /* Emit the assembly bits to indicate that DECL is globally visible. */
5608 static void
5609 globalize_decl (tree decl)
5612 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5613 if (DECL_WEAK (decl))
5615 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5616 tree *p, t;
5618 #ifdef ASM_WEAKEN_DECL
5619 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5620 #else
5621 ASM_WEAKEN_LABEL (asm_out_file, name);
5622 #endif
5624 /* Remove this function from the pending weak list so that
5625 we do not emit multiple .weak directives for it. */
5626 for (p = &weak_decls; (t = *p) ; )
5628 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5629 *p = TREE_CHAIN (t);
5630 else
5631 p = &TREE_CHAIN (t);
5634 /* Remove weakrefs to the same target from the pending weakref
5635 list, for the same reason. */
5636 for (p = &weakref_targets; (t = *p) ; )
5638 if (DECL_ASSEMBLER_NAME (decl)
5639 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5640 *p = TREE_CHAIN (t);
5641 else
5642 p = &TREE_CHAIN (t);
5645 return;
5647 #endif
5649 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5652 vec<alias_pair, va_gc> *alias_pairs;
5654 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5655 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5656 tree node is DECL to have the value of the tree node TARGET. */
5658 void
5659 do_assemble_alias (tree decl, tree target)
5661 tree id;
5663 /* Emulated TLS had better not get this var. */
5664 gcc_assert (!(!targetm.have_tls
5665 && VAR_P (decl)
5666 && DECL_THREAD_LOCAL_P (decl)));
5668 if (TREE_ASM_WRITTEN (decl))
5669 return;
5671 id = DECL_ASSEMBLER_NAME (decl);
5672 ultimate_transparent_alias_target (&id);
5673 ultimate_transparent_alias_target (&target);
5675 /* We must force creation of DECL_RTL for debug info generation, even though
5676 we don't use it here. */
5677 make_decl_rtl (decl);
5679 TREE_ASM_WRITTEN (decl) = 1;
5680 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5681 TREE_ASM_WRITTEN (id) = 1;
5683 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5685 if (!TREE_SYMBOL_REFERENCED (target))
5686 weakref_targets = tree_cons (decl, target, weakref_targets);
5688 #ifdef ASM_OUTPUT_WEAKREF
5689 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5690 IDENTIFIER_POINTER (id),
5691 IDENTIFIER_POINTER (target));
5692 #else
5693 if (!TARGET_SUPPORTS_WEAK)
5695 error_at (DECL_SOURCE_LOCATION (decl),
5696 "weakref is not supported in this configuration");
5697 return;
5699 #endif
5700 return;
5703 #ifdef ASM_OUTPUT_DEF
5704 tree orig_decl = decl;
5706 if (TREE_CODE (decl) == FUNCTION_DECL
5707 && cgraph_node::get (decl)->instrumentation_clone
5708 && cgraph_node::get (decl)->instrumented_version)
5709 orig_decl = cgraph_node::get (decl)->instrumented_version->decl;
5711 /* Make name accessible from other files, if appropriate. */
5713 if (TREE_PUBLIC (decl) || TREE_PUBLIC (orig_decl))
5715 globalize_decl (decl);
5716 maybe_assemble_visibility (decl);
5718 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5720 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5721 if (targetm.has_ifunc_p ())
5722 ASM_OUTPUT_TYPE_DIRECTIVE
5723 (asm_out_file, IDENTIFIER_POINTER (id),
5724 IFUNC_ASM_TYPE);
5725 else
5726 #endif
5727 error_at (DECL_SOURCE_LOCATION (decl),
5728 "ifunc is not supported on this target");
5731 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5732 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5733 # else
5734 ASM_OUTPUT_DEF (asm_out_file,
5735 IDENTIFIER_POINTER (id),
5736 IDENTIFIER_POINTER (target));
5737 # endif
5738 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5740 const char *name;
5741 tree *p, t;
5743 name = IDENTIFIER_POINTER (id);
5744 # ifdef ASM_WEAKEN_DECL
5745 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5746 # else
5747 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5748 # endif
5749 /* Remove this function from the pending weak list so that
5750 we do not emit multiple .weak directives for it. */
5751 for (p = &weak_decls; (t = *p) ; )
5752 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t))
5753 || id == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5754 *p = TREE_CHAIN (t);
5755 else
5756 p = &TREE_CHAIN (t);
5758 /* Remove weakrefs to the same target from the pending weakref
5759 list, for the same reason. */
5760 for (p = &weakref_targets; (t = *p) ; )
5762 if (id == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5763 *p = TREE_CHAIN (t);
5764 else
5765 p = &TREE_CHAIN (t);
5768 #endif
5771 /* Emit an assembler directive to make the symbol for DECL an alias to
5772 the symbol for TARGET. */
5774 void
5775 assemble_alias (tree decl, tree target)
5777 tree target_decl;
5779 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5781 tree alias = DECL_ASSEMBLER_NAME (decl);
5783 ultimate_transparent_alias_target (&target);
5785 if (alias == target)
5786 error ("weakref %q+D ultimately targets itself", decl);
5787 if (TREE_PUBLIC (decl))
5788 error ("weakref %q+D must have static linkage", decl);
5790 else
5792 #if !defined (ASM_OUTPUT_DEF)
5793 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5794 error_at (DECL_SOURCE_LOCATION (decl),
5795 "alias definitions not supported in this configuration");
5796 TREE_ASM_WRITTEN (decl) = 1;
5797 return;
5798 # else
5799 if (!DECL_WEAK (decl))
5801 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5802 error_at (DECL_SOURCE_LOCATION (decl),
5803 "ifunc is not supported in this configuration");
5804 else
5805 error_at (DECL_SOURCE_LOCATION (decl),
5806 "only weak aliases are supported in this configuration");
5807 TREE_ASM_WRITTEN (decl) = 1;
5808 return;
5810 # endif
5811 #endif
5813 TREE_USED (decl) = 1;
5815 /* Allow aliases to aliases. */
5816 if (TREE_CODE (decl) == FUNCTION_DECL)
5817 cgraph_node::get_create (decl)->alias = true;
5818 else
5819 varpool_node::get_create (decl)->alias = true;
5821 /* If the target has already been emitted, we don't have to queue the
5822 alias. This saves a tad of memory. */
5823 if (symtab->global_info_ready)
5824 target_decl = find_decl (target);
5825 else
5826 target_decl= NULL;
5827 if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5828 || symtab->state >= EXPANSION)
5829 do_assemble_alias (decl, target);
5830 else
5832 alias_pair p = {decl, target};
5833 vec_safe_push (alias_pairs, p);
5837 /* Record and output a table of translations from original function
5838 to its transaction aware clone. Note that tm_pure functions are
5839 considered to be their own clone. */
5841 struct tm_clone_hasher : ggc_cache_ptr_hash<tree_map>
5843 static hashval_t hash (tree_map *m) { return tree_map_hash (m); }
5844 static bool equal (tree_map *a, tree_map *b) { return tree_map_eq (a, b); }
5846 static int
5847 keep_cache_entry (tree_map *&e)
5849 return ggc_marked_p (e->base.from);
5853 static GTY((cache)) hash_table<tm_clone_hasher> *tm_clone_hash;
5855 void
5856 record_tm_clone_pair (tree o, tree n)
5858 struct tree_map **slot, *h;
5860 if (tm_clone_hash == NULL)
5861 tm_clone_hash = hash_table<tm_clone_hasher>::create_ggc (32);
5863 h = ggc_alloc<tree_map> ();
5864 h->hash = htab_hash_pointer (o);
5865 h->base.from = o;
5866 h->to = n;
5868 slot = tm_clone_hash->find_slot_with_hash (h, h->hash, INSERT);
5869 *slot = h;
5872 tree
5873 get_tm_clone_pair (tree o)
5875 if (tm_clone_hash)
5877 struct tree_map *h, in;
5879 in.base.from = o;
5880 in.hash = htab_hash_pointer (o);
5881 h = tm_clone_hash->find_with_hash (&in, in.hash);
5882 if (h)
5883 return h->to;
5885 return NULL_TREE;
5888 struct tm_alias_pair
5890 unsigned int uid;
5891 tree from;
5892 tree to;
5896 /* Dump the actual pairs to the .tm_clone_table section. */
5898 static void
5899 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
5901 unsigned i;
5902 tm_alias_pair *p;
5903 bool switched = false;
5905 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
5907 tree src = p->from;
5908 tree dst = p->to;
5909 struct cgraph_node *src_n = cgraph_node::get (src);
5910 struct cgraph_node *dst_n = cgraph_node::get (dst);
5912 /* The function ipa_tm_create_version() marks the clone as needed if
5913 the original function was needed. But we also mark the clone as
5914 needed if we ever called the clone indirectly through
5915 TM_GETTMCLONE. If neither of these are true, we didn't generate
5916 a clone, and we didn't call it indirectly... no sense keeping it
5917 in the clone table. */
5918 if (!dst_n || !dst_n->definition)
5919 continue;
5921 /* This covers the case where we have optimized the original
5922 function away, and only access the transactional clone. */
5923 if (!src_n || !src_n->definition)
5924 continue;
5926 if (!switched)
5928 switch_to_section (targetm.asm_out.tm_clone_table_section ());
5929 assemble_align (POINTER_SIZE);
5930 switched = true;
5933 assemble_integer (XEXP (DECL_RTL (src), 0),
5934 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
5935 assemble_integer (XEXP (DECL_RTL (dst), 0),
5936 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
5940 /* Provide a default for the tm_clone_table section. */
5942 section *
5943 default_clone_table_section (void)
5945 return get_named_section (NULL, ".tm_clone_table", 3);
5948 /* Helper comparison function for qsorting by the DECL_UID stored in
5949 alias_pair->emitted_diags. */
5951 static int
5952 tm_alias_pair_cmp (const void *x, const void *y)
5954 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
5955 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
5956 if (p1->uid < p2->uid)
5957 return -1;
5958 if (p1->uid > p2->uid)
5959 return 1;
5960 return 0;
5963 void
5964 finish_tm_clone_pairs (void)
5966 vec<tm_alias_pair> tm_alias_pairs = vNULL;
5968 if (tm_clone_hash == NULL)
5969 return;
5971 /* We need a determenistic order for the .tm_clone_table, otherwise
5972 we will get bootstrap comparison failures, so dump the hash table
5973 to a vector, sort it, and dump the vector. */
5975 /* Dump the hashtable to a vector. */
5976 tree_map *map;
5977 hash_table<tm_clone_hasher>::iterator iter;
5978 FOR_EACH_HASH_TABLE_ELEMENT (*tm_clone_hash, map, tree_map *, iter)
5980 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
5981 tm_alias_pairs.safe_push (p);
5983 /* Sort it. */
5984 tm_alias_pairs.qsort (tm_alias_pair_cmp);
5986 /* Dump it. */
5987 dump_tm_clone_pairs (tm_alias_pairs);
5989 tm_clone_hash->empty ();
5990 tm_clone_hash = NULL;
5991 tm_alias_pairs.release ();
5995 /* Emit an assembler directive to set symbol for DECL visibility to
5996 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
5998 void
5999 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
6000 int vis ATTRIBUTE_UNUSED)
6002 #ifdef HAVE_GAS_HIDDEN
6003 static const char * const visibility_types[] = {
6004 NULL, "protected", "hidden", "internal"
6007 const char *name, *type;
6008 tree id;
6010 id = DECL_ASSEMBLER_NAME (decl);
6011 ultimate_transparent_alias_target (&id);
6012 name = IDENTIFIER_POINTER (id);
6014 type = visibility_types[vis];
6016 fprintf (asm_out_file, "\t.%s\t", type);
6017 assemble_name (asm_out_file, name);
6018 fprintf (asm_out_file, "\n");
6019 #else
6020 if (!DECL_ARTIFICIAL (decl))
6021 warning (OPT_Wattributes, "visibility attribute not supported "
6022 "in this configuration; ignored");
6023 #endif
6026 /* A helper function to call assemble_visibility when needed for a decl. */
6029 maybe_assemble_visibility (tree decl)
6031 enum symbol_visibility vis = DECL_VISIBILITY (decl);
6033 if (TREE_CODE (decl) == FUNCTION_DECL
6034 && cgraph_node::get (decl)
6035 && cgraph_node::get (decl)->instrumentation_clone
6036 && cgraph_node::get (decl)->instrumented_version)
6037 vis = DECL_VISIBILITY (cgraph_node::get (decl)->instrumented_version->decl);
6039 if (vis != VISIBILITY_DEFAULT)
6041 targetm.asm_out.assemble_visibility (decl, vis);
6042 return 1;
6044 else
6045 return 0;
6048 /* Returns 1 if the target configuration supports defining public symbols
6049 so that one of them will be chosen at link time instead of generating a
6050 multiply-defined symbol error, whether through the use of weak symbols or
6051 a target-specific mechanism for having duplicates discarded. */
6054 supports_one_only (void)
6056 if (SUPPORTS_ONE_ONLY)
6057 return 1;
6058 return TARGET_SUPPORTS_WEAK;
6061 /* Set up DECL as a public symbol that can be defined in multiple
6062 translation units without generating a linker error. */
6064 void
6065 make_decl_one_only (tree decl, tree comdat_group)
6067 struct symtab_node *symbol;
6068 gcc_assert (VAR_OR_FUNCTION_DECL_P (decl));
6070 TREE_PUBLIC (decl) = 1;
6072 if (VAR_P (decl))
6073 symbol = varpool_node::get_create (decl);
6074 else
6075 symbol = cgraph_node::get_create (decl);
6077 if (SUPPORTS_ONE_ONLY)
6079 #ifdef MAKE_DECL_ONE_ONLY
6080 MAKE_DECL_ONE_ONLY (decl);
6081 #endif
6082 symbol->set_comdat_group (comdat_group);
6084 else if (VAR_P (decl)
6085 && (DECL_INITIAL (decl) == 0
6086 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
6087 DECL_COMMON (decl) = 1;
6088 else
6090 gcc_assert (TARGET_SUPPORTS_WEAK);
6091 DECL_WEAK (decl) = 1;
6095 void
6096 init_varasm_once (void)
6098 section_htab = hash_table<section_hasher>::create_ggc (31);
6099 object_block_htab = hash_table<object_block_hasher>::create_ggc (31);
6100 const_desc_htab = hash_table<tree_descriptor_hasher>::create_ggc (1009);
6102 shared_constant_pool = create_constant_pool ();
6104 #ifdef TEXT_SECTION_ASM_OP
6105 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
6106 TEXT_SECTION_ASM_OP);
6107 #endif
6109 #ifdef DATA_SECTION_ASM_OP
6110 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
6111 DATA_SECTION_ASM_OP);
6112 #endif
6114 #ifdef SDATA_SECTION_ASM_OP
6115 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
6116 SDATA_SECTION_ASM_OP);
6117 #endif
6119 #ifdef READONLY_DATA_SECTION_ASM_OP
6120 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
6121 READONLY_DATA_SECTION_ASM_OP);
6122 #endif
6124 #ifdef CTORS_SECTION_ASM_OP
6125 ctors_section = get_unnamed_section (0, output_section_asm_op,
6126 CTORS_SECTION_ASM_OP);
6127 #endif
6129 #ifdef DTORS_SECTION_ASM_OP
6130 dtors_section = get_unnamed_section (0, output_section_asm_op,
6131 DTORS_SECTION_ASM_OP);
6132 #endif
6134 #ifdef BSS_SECTION_ASM_OP
6135 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6136 output_section_asm_op,
6137 BSS_SECTION_ASM_OP);
6138 #endif
6140 #ifdef SBSS_SECTION_ASM_OP
6141 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6142 output_section_asm_op,
6143 SBSS_SECTION_ASM_OP);
6144 #endif
6146 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6147 | SECTION_COMMON, emit_tls_common);
6148 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6149 | SECTION_COMMON, emit_local);
6150 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6151 | SECTION_COMMON, emit_common);
6153 #if defined ASM_OUTPUT_ALIGNED_BSS
6154 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
6155 emit_bss);
6156 #endif
6158 targetm.asm_out.init_sections ();
6160 if (readonly_data_section == NULL)
6161 readonly_data_section = text_section;
6163 #ifdef ASM_OUTPUT_EXTERNAL
6164 pending_assemble_externals_set = new hash_set<tree>;
6165 #endif
6168 enum tls_model
6169 decl_default_tls_model (const_tree decl)
6171 enum tls_model kind;
6172 bool is_local;
6174 is_local = targetm.binds_local_p (decl);
6175 if (!flag_shlib)
6177 if (is_local)
6178 kind = TLS_MODEL_LOCAL_EXEC;
6179 else
6180 kind = TLS_MODEL_INITIAL_EXEC;
6183 /* Local dynamic is inefficient when we're not combining the
6184 parts of the address. */
6185 else if (optimize && is_local)
6186 kind = TLS_MODEL_LOCAL_DYNAMIC;
6187 else
6188 kind = TLS_MODEL_GLOBAL_DYNAMIC;
6189 if (kind < flag_tls_default)
6190 kind = flag_tls_default;
6192 return kind;
6195 /* Select a set of attributes for section NAME based on the properties
6196 of DECL and whether or not RELOC indicates that DECL's initializer
6197 might contain runtime relocations.
6199 We make the section read-only and executable for a function decl,
6200 read-only for a const data decl, and writable for a non-const data decl. */
6202 unsigned int
6203 default_section_type_flags (tree decl, const char *name, int reloc)
6205 unsigned int flags;
6207 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6208 flags = SECTION_CODE;
6209 else if (decl)
6211 enum section_category category
6212 = categorize_decl_for_section (decl, reloc);
6213 if (decl_readonly_section_1 (category))
6214 flags = 0;
6215 else if (category == SECCAT_DATA_REL_RO
6216 || category == SECCAT_DATA_REL_RO_LOCAL)
6217 flags = SECTION_WRITE | SECTION_RELRO;
6218 else
6219 flags = SECTION_WRITE;
6221 else
6223 flags = SECTION_WRITE;
6224 if (strcmp (name, ".data.rel.ro") == 0
6225 || strcmp (name, ".data.rel.ro.local") == 0)
6226 flags |= SECTION_RELRO;
6229 if (decl && DECL_P (decl) && DECL_COMDAT_GROUP (decl))
6230 flags |= SECTION_LINKONCE;
6232 if (strcmp (name, ".vtable_map_vars") == 0)
6233 flags |= SECTION_LINKONCE;
6235 if (decl && VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6236 flags |= SECTION_TLS | SECTION_WRITE;
6238 if (strcmp (name, ".bss") == 0
6239 || strncmp (name, ".bss.", 5) == 0
6240 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6241 || strcmp (name, ".persistent.bss") == 0
6242 || strcmp (name, ".sbss") == 0
6243 || strncmp (name, ".sbss.", 6) == 0
6244 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6245 flags |= SECTION_BSS;
6247 if (strcmp (name, ".tdata") == 0
6248 || strncmp (name, ".tdata.", 7) == 0
6249 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6250 flags |= SECTION_TLS;
6252 if (strcmp (name, ".tbss") == 0
6253 || strncmp (name, ".tbss.", 6) == 0
6254 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6255 flags |= SECTION_TLS | SECTION_BSS;
6257 /* These three sections have special ELF types. They are neither
6258 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
6259 want to print a section type (@progbits or @nobits). If someone
6260 is silly enough to emit code or TLS variables to one of these
6261 sections, then don't handle them specially. */
6262 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6263 && (strcmp (name, ".init_array") == 0
6264 || strcmp (name, ".fini_array") == 0
6265 || strcmp (name, ".preinit_array") == 0))
6266 flags |= SECTION_NOTYPE;
6268 return flags;
6271 /* Return true if the target supports some form of global BSS,
6272 either through bss_noswitch_section, or by selecting a BSS
6273 section in TARGET_ASM_SELECT_SECTION. */
6275 bool
6276 have_global_bss_p (void)
6278 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6281 /* Output assembly to switch to section NAME with attribute FLAGS.
6282 Four variants for common object file formats. */
6284 void
6285 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6286 unsigned int flags ATTRIBUTE_UNUSED,
6287 tree decl ATTRIBUTE_UNUSED)
6289 /* Some object formats don't support named sections at all. The
6290 front-end should already have flagged this as an error. */
6291 gcc_unreachable ();
6294 #ifndef TLS_SECTION_ASM_FLAG
6295 #define TLS_SECTION_ASM_FLAG 'T'
6296 #endif
6298 void
6299 default_elf_asm_named_section (const char *name, unsigned int flags,
6300 tree decl)
6302 char flagchars[11], *f = flagchars;
6303 unsigned int numeric_value = 0;
6305 /* If we have already declared this section, we can use an
6306 abbreviated form to switch back to it -- unless this section is
6307 part of a COMDAT groups, in which case GAS requires the full
6308 declaration every time. */
6309 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6310 && (flags & SECTION_DECLARED))
6312 fprintf (asm_out_file, "\t.section\t%s\n", name);
6313 return;
6316 /* If we have a machine specific flag, then use the numeric value to pass
6317 this on to GAS. */
6318 if (targetm.asm_out.elf_flags_numeric (flags, &numeric_value))
6319 snprintf (f, sizeof (flagchars), "0x%08x", numeric_value);
6320 else
6322 if (!(flags & SECTION_DEBUG))
6323 *f++ = 'a';
6324 #if defined (HAVE_GAS_SECTION_EXCLUDE) && HAVE_GAS_SECTION_EXCLUDE == 1
6325 if (flags & SECTION_EXCLUDE)
6326 *f++ = 'e';
6327 #endif
6328 if (flags & SECTION_WRITE)
6329 *f++ = 'w';
6330 if (flags & SECTION_CODE)
6331 *f++ = 'x';
6332 if (flags & SECTION_SMALL)
6333 *f++ = 's';
6334 if (flags & SECTION_MERGE)
6335 *f++ = 'M';
6336 if (flags & SECTION_STRINGS)
6337 *f++ = 'S';
6338 if (flags & SECTION_TLS)
6339 *f++ = TLS_SECTION_ASM_FLAG;
6340 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6341 *f++ = 'G';
6342 #ifdef MACH_DEP_SECTION_ASM_FLAG
6343 if (flags & SECTION_MACH_DEP)
6344 *f++ = MACH_DEP_SECTION_ASM_FLAG;
6345 #endif
6346 *f = '\0';
6349 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6351 if (!(flags & SECTION_NOTYPE))
6353 const char *type;
6354 const char *format;
6356 if (flags & SECTION_BSS)
6357 type = "nobits";
6358 else
6359 type = "progbits";
6361 format = ",@%s";
6362 /* On platforms that use "@" as the assembly comment character,
6363 use "%" instead. */
6364 if (strcmp (ASM_COMMENT_START, "@") == 0)
6365 format = ",%%%s";
6366 fprintf (asm_out_file, format, type);
6368 if (flags & SECTION_ENTSIZE)
6369 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6370 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6372 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6373 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6374 else
6375 fprintf (asm_out_file, ",%s,comdat",
6376 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6380 putc ('\n', asm_out_file);
6383 void
6384 default_coff_asm_named_section (const char *name, unsigned int flags,
6385 tree decl ATTRIBUTE_UNUSED)
6387 char flagchars[8], *f = flagchars;
6389 if (flags & SECTION_WRITE)
6390 *f++ = 'w';
6391 if (flags & SECTION_CODE)
6392 *f++ = 'x';
6393 *f = '\0';
6395 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6398 void
6399 default_pe_asm_named_section (const char *name, unsigned int flags,
6400 tree decl)
6402 default_coff_asm_named_section (name, flags, decl);
6404 if (flags & SECTION_LINKONCE)
6406 /* Functions may have been compiled at various levels of
6407 optimization so we can't use `same_size' here.
6408 Instead, have the linker pick one. */
6409 fprintf (asm_out_file, "\t.linkonce %s\n",
6410 (flags & SECTION_CODE ? "discard" : "same_size"));
6414 /* The lame default section selector. */
6416 section *
6417 default_select_section (tree decl, int reloc,
6418 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6420 if (DECL_P (decl))
6422 if (decl_readonly_section (decl, reloc))
6423 return readonly_data_section;
6425 else if (TREE_CODE (decl) == CONSTRUCTOR)
6427 if (! ((flag_pic && reloc)
6428 || !TREE_READONLY (decl)
6429 || TREE_SIDE_EFFECTS (decl)
6430 || !TREE_CONSTANT (decl)))
6431 return readonly_data_section;
6433 else if (TREE_CODE (decl) == STRING_CST)
6434 return readonly_data_section;
6435 else if (! (flag_pic && reloc))
6436 return readonly_data_section;
6438 return data_section;
6441 enum section_category
6442 categorize_decl_for_section (const_tree decl, int reloc)
6444 enum section_category ret;
6446 if (TREE_CODE (decl) == FUNCTION_DECL)
6447 return SECCAT_TEXT;
6448 else if (TREE_CODE (decl) == STRING_CST)
6450 if ((flag_sanitize & SANITIZE_ADDRESS)
6451 && asan_protect_global (CONST_CAST_TREE (decl)))
6452 /* or !flag_merge_constants */
6453 return SECCAT_RODATA;
6454 else
6455 return SECCAT_RODATA_MERGE_STR;
6457 else if (VAR_P (decl))
6459 if (bss_initializer_p (decl))
6460 ret = SECCAT_BSS;
6461 else if (! TREE_READONLY (decl)
6462 || TREE_SIDE_EFFECTS (decl)
6463 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
6465 /* Here the reloc_rw_mask is not testing whether the section should
6466 be read-only or not, but whether the dynamic link will have to
6467 do something. If so, we wish to segregate the data in order to
6468 minimize cache misses inside the dynamic linker. */
6469 if (reloc & targetm.asm_out.reloc_rw_mask ())
6470 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6471 else
6472 ret = SECCAT_DATA;
6474 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6475 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6476 else if (reloc || flag_merge_constants < 2
6477 || ((flag_sanitize & SANITIZE_ADDRESS)
6478 && asan_protect_global (CONST_CAST_TREE (decl))))
6479 /* C and C++ don't allow different variables to share the same
6480 location. -fmerge-all-constants allows even that (at the
6481 expense of not conforming). */
6482 ret = SECCAT_RODATA;
6483 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6484 ret = SECCAT_RODATA_MERGE_STR_INIT;
6485 else
6486 ret = SECCAT_RODATA_MERGE_CONST;
6488 else if (TREE_CODE (decl) == CONSTRUCTOR)
6490 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6491 || TREE_SIDE_EFFECTS (decl)
6492 || ! TREE_CONSTANT (decl))
6493 ret = SECCAT_DATA;
6494 else
6495 ret = SECCAT_RODATA;
6497 else
6498 ret = SECCAT_RODATA;
6500 /* There are no read-only thread-local sections. */
6501 if (VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6503 /* Note that this would be *just* SECCAT_BSS, except that there's
6504 no concept of a read-only thread-local-data section. */
6505 if (ret == SECCAT_BSS
6506 || (flag_zero_initialized_in_bss
6507 && initializer_zerop (DECL_INITIAL (decl))))
6508 ret = SECCAT_TBSS;
6509 else
6510 ret = SECCAT_TDATA;
6513 /* If the target uses small data sections, select it. */
6514 else if (targetm.in_small_data_p (decl))
6516 if (ret == SECCAT_BSS)
6517 ret = SECCAT_SBSS;
6518 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6519 ret = SECCAT_SRODATA;
6520 else
6521 ret = SECCAT_SDATA;
6524 return ret;
6527 static bool
6528 decl_readonly_section_1 (enum section_category category)
6530 switch (category)
6532 case SECCAT_RODATA:
6533 case SECCAT_RODATA_MERGE_STR:
6534 case SECCAT_RODATA_MERGE_STR_INIT:
6535 case SECCAT_RODATA_MERGE_CONST:
6536 case SECCAT_SRODATA:
6537 return true;
6538 default:
6539 return false;
6543 bool
6544 decl_readonly_section (const_tree decl, int reloc)
6546 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6549 /* Select a section based on the above categorization. */
6551 section *
6552 default_elf_select_section (tree decl, int reloc,
6553 unsigned HOST_WIDE_INT align)
6555 const char *sname;
6556 switch (categorize_decl_for_section (decl, reloc))
6558 case SECCAT_TEXT:
6559 /* We're not supposed to be called on FUNCTION_DECLs. */
6560 gcc_unreachable ();
6561 case SECCAT_RODATA:
6562 return readonly_data_section;
6563 case SECCAT_RODATA_MERGE_STR:
6564 return mergeable_string_section (decl, align, 0);
6565 case SECCAT_RODATA_MERGE_STR_INIT:
6566 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6567 case SECCAT_RODATA_MERGE_CONST:
6568 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6569 case SECCAT_SRODATA:
6570 sname = ".sdata2";
6571 break;
6572 case SECCAT_DATA:
6573 return data_section;
6574 case SECCAT_DATA_REL:
6575 sname = ".data.rel";
6576 break;
6577 case SECCAT_DATA_REL_LOCAL:
6578 sname = ".data.rel.local";
6579 break;
6580 case SECCAT_DATA_REL_RO:
6581 sname = ".data.rel.ro";
6582 break;
6583 case SECCAT_DATA_REL_RO_LOCAL:
6584 sname = ".data.rel.ro.local";
6585 break;
6586 case SECCAT_SDATA:
6587 sname = ".sdata";
6588 break;
6589 case SECCAT_TDATA:
6590 sname = ".tdata";
6591 break;
6592 case SECCAT_BSS:
6593 if (bss_section)
6594 return bss_section;
6595 sname = ".bss";
6596 break;
6597 case SECCAT_SBSS:
6598 sname = ".sbss";
6599 break;
6600 case SECCAT_TBSS:
6601 sname = ".tbss";
6602 break;
6603 default:
6604 gcc_unreachable ();
6607 return get_named_section (decl, sname, reloc);
6610 /* Construct a unique section name based on the decl name and the
6611 categorization performed above. */
6613 void
6614 default_unique_section (tree decl, int reloc)
6616 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6617 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6618 const char *prefix, *name, *linkonce;
6619 char *string;
6620 tree id;
6622 switch (categorize_decl_for_section (decl, reloc))
6624 case SECCAT_TEXT:
6625 prefix = one_only ? ".t" : ".text";
6626 break;
6627 case SECCAT_RODATA:
6628 case SECCAT_RODATA_MERGE_STR:
6629 case SECCAT_RODATA_MERGE_STR_INIT:
6630 case SECCAT_RODATA_MERGE_CONST:
6631 prefix = one_only ? ".r" : ".rodata";
6632 break;
6633 case SECCAT_SRODATA:
6634 prefix = one_only ? ".s2" : ".sdata2";
6635 break;
6636 case SECCAT_DATA:
6637 prefix = one_only ? ".d" : ".data";
6638 break;
6639 case SECCAT_DATA_REL:
6640 prefix = one_only ? ".d.rel" : ".data.rel";
6641 break;
6642 case SECCAT_DATA_REL_LOCAL:
6643 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6644 break;
6645 case SECCAT_DATA_REL_RO:
6646 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6647 break;
6648 case SECCAT_DATA_REL_RO_LOCAL:
6649 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6650 break;
6651 case SECCAT_SDATA:
6652 prefix = one_only ? ".s" : ".sdata";
6653 break;
6654 case SECCAT_BSS:
6655 prefix = one_only ? ".b" : ".bss";
6656 break;
6657 case SECCAT_SBSS:
6658 prefix = one_only ? ".sb" : ".sbss";
6659 break;
6660 case SECCAT_TDATA:
6661 prefix = one_only ? ".td" : ".tdata";
6662 break;
6663 case SECCAT_TBSS:
6664 prefix = one_only ? ".tb" : ".tbss";
6665 break;
6666 default:
6667 gcc_unreachable ();
6670 id = DECL_ASSEMBLER_NAME (decl);
6671 ultimate_transparent_alias_target (&id);
6672 name = IDENTIFIER_POINTER (id);
6673 name = targetm.strip_name_encoding (name);
6675 /* If we're using one_only, then there needs to be a .gnu.linkonce
6676 prefix to the section name. */
6677 linkonce = one_only ? ".gnu.linkonce" : "";
6679 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6681 set_decl_section_name (decl, string);
6684 /* Subroutine of compute_reloc_for_rtx for leaf rtxes. */
6686 static int
6687 compute_reloc_for_rtx_1 (const_rtx x)
6689 switch (GET_CODE (x))
6691 case SYMBOL_REF:
6692 return SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6693 case LABEL_REF:
6694 return 1;
6695 default:
6696 return 0;
6700 /* Like compute_reloc_for_constant, except for an RTX. The return value
6701 is a mask for which bit 1 indicates a global relocation, and bit 0
6702 indicates a local relocation. */
6704 static int
6705 compute_reloc_for_rtx (const_rtx x)
6707 switch (GET_CODE (x))
6709 case SYMBOL_REF:
6710 case LABEL_REF:
6711 return compute_reloc_for_rtx_1 (x);
6713 case CONST:
6715 int reloc = 0;
6716 subrtx_iterator::array_type array;
6717 FOR_EACH_SUBRTX (iter, array, x, ALL)
6718 reloc |= compute_reloc_for_rtx_1 (*iter);
6719 return reloc;
6722 default:
6723 return 0;
6727 section *
6728 default_select_rtx_section (machine_mode mode ATTRIBUTE_UNUSED,
6729 rtx x,
6730 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6732 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6733 return data_section;
6734 else
6735 return readonly_data_section;
6738 section *
6739 default_elf_select_rtx_section (machine_mode mode, rtx x,
6740 unsigned HOST_WIDE_INT align)
6742 int reloc = compute_reloc_for_rtx (x);
6744 /* ??? Handle small data here somehow. */
6746 if (reloc & targetm.asm_out.reloc_rw_mask ())
6748 if (reloc == 1)
6749 return get_named_section (NULL, ".data.rel.ro.local", 1);
6750 else
6751 return get_named_section (NULL, ".data.rel.ro", 3);
6754 return mergeable_constant_section (mode, align, 0);
6757 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6759 void
6760 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6762 rtx symbol;
6763 int flags;
6765 /* Careful not to prod global register variables. */
6766 if (!MEM_P (rtl))
6767 return;
6768 symbol = XEXP (rtl, 0);
6769 if (GET_CODE (symbol) != SYMBOL_REF)
6770 return;
6772 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6773 if (TREE_CODE (decl) == FUNCTION_DECL)
6774 flags |= SYMBOL_FLAG_FUNCTION;
6775 if (targetm.binds_local_p (decl))
6776 flags |= SYMBOL_FLAG_LOCAL;
6777 if (VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6778 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6779 else if (targetm.in_small_data_p (decl))
6780 flags |= SYMBOL_FLAG_SMALL;
6781 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6782 being PUBLIC, the thing *must* be defined in this translation unit.
6783 Prevent this buglet from being propagated into rtl code as well. */
6784 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6785 flags |= SYMBOL_FLAG_EXTERNAL;
6787 SYMBOL_REF_FLAGS (symbol) = flags;
6790 /* By default, we do nothing for encode_section_info, so we need not
6791 do anything but discard the '*' marker. */
6793 const char *
6794 default_strip_name_encoding (const char *str)
6796 return str + (*str == '*');
6799 #ifdef ASM_OUTPUT_DEF
6800 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6801 anchor relative to ".", the current section position. */
6803 void
6804 default_asm_output_anchor (rtx symbol)
6806 char buffer[100];
6808 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6809 SYMBOL_REF_BLOCK_OFFSET (symbol));
6810 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6812 #endif
6814 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6816 bool
6817 default_use_anchors_for_symbol_p (const_rtx symbol)
6819 section *sect;
6820 tree decl;
6822 /* Don't use anchors for mergeable sections. The linker might move
6823 the objects around. */
6824 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6825 if (sect->common.flags & SECTION_MERGE)
6826 return false;
6828 /* Don't use anchors for small data sections. The small data register
6829 acts as an anchor for such sections. */
6830 if (sect->common.flags & SECTION_SMALL)
6831 return false;
6833 decl = SYMBOL_REF_DECL (symbol);
6834 if (decl && DECL_P (decl))
6836 /* Don't use section anchors for decls that might be defined or
6837 usurped by other modules. */
6838 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6839 return false;
6841 /* Don't use section anchors for decls that will be placed in a
6842 small data section. */
6843 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6844 one above. The problem is that we only use SECTION_SMALL for
6845 sections that should be marked as small in the section directive. */
6846 if (targetm.in_small_data_p (decl))
6847 return false;
6849 /* Don't use section anchors for decls that won't fit inside a single
6850 anchor range to reduce the amount of instructions required to refer
6851 to the entire declaration. */
6852 if (DECL_SIZE_UNIT (decl) == NULL_TREE
6853 || !tree_fits_uhwi_p (DECL_SIZE_UNIT (decl))
6854 || (tree_to_uhwi (DECL_SIZE_UNIT (decl))
6855 >= (unsigned HOST_WIDE_INT) targetm.max_anchor_offset))
6856 return false;
6859 return true;
6862 /* Return true when RESOLUTION indicate that symbol will be bound to the
6863 definition provided by current .o file. */
6865 static bool
6866 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
6868 return (resolution == LDPR_PREVAILING_DEF
6869 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6870 || resolution == LDPR_PREVAILING_DEF_IRONLY);
6873 /* Return true when RESOLUTION indicate that symbol will be bound locally
6874 within current executable or DSO. */
6876 static bool
6877 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
6879 return (resolution == LDPR_PREVAILING_DEF
6880 || resolution == LDPR_PREVAILING_DEF_IRONLY
6881 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6882 || resolution == LDPR_PREEMPTED_REG
6883 || resolution == LDPR_PREEMPTED_IR
6884 || resolution == LDPR_RESOLVED_IR
6885 || resolution == LDPR_RESOLVED_EXEC);
6888 /* COMMON_LOCAL_P is true means that the linker can guarantee that an
6889 uninitialized common symbol in the executable will still be defined
6890 (through COPY relocation) in the executable. */
6892 bool
6893 default_binds_local_p_3 (const_tree exp, bool shlib, bool weak_dominate,
6894 bool extern_protected_data, bool common_local_p)
6896 /* A non-decl is an entry in the constant pool. */
6897 if (!DECL_P (exp))
6898 return true;
6900 /* Weakrefs may not bind locally, even though the weakref itself is always
6901 static and therefore local. Similarly, the resolver for ifunc functions
6902 might resolve to a non-local function.
6903 FIXME: We can resolve the weakref case more curefuly by looking at the
6904 weakref alias. */
6905 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
6906 || (TREE_CODE (exp) == FUNCTION_DECL
6907 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
6908 return false;
6910 /* Static variables are always local. */
6911 if (! TREE_PUBLIC (exp))
6912 return true;
6914 /* With resolution file in hand, take look into resolutions.
6915 We can't just return true for resolved_locally symbols,
6916 because dynamic linking might overwrite symbols
6917 in shared libraries. */
6918 bool resolved_locally = false;
6920 bool uninited_common = (DECL_COMMON (exp)
6921 && (DECL_INITIAL (exp) == NULL
6922 || (!in_lto_p
6923 && DECL_INITIAL (exp) == error_mark_node)));
6925 /* A non-external variable is defined locally only if it isn't
6926 uninitialized COMMON variable or common_local_p is true. */
6927 bool defined_locally = (!DECL_EXTERNAL (exp)
6928 && (!uninited_common || common_local_p));
6929 if (symtab_node *node = symtab_node::get (exp))
6931 if (node->in_other_partition)
6932 defined_locally = true;
6933 if (node->can_be_discarded_p ())
6935 else if (resolution_to_local_definition_p (node->resolution))
6936 defined_locally = resolved_locally = true;
6937 else if (resolution_local_p (node->resolution))
6938 resolved_locally = true;
6940 if (defined_locally && weak_dominate && !shlib)
6941 resolved_locally = true;
6943 /* Undefined weak symbols are never defined locally. */
6944 if (DECL_WEAK (exp) && !defined_locally)
6945 return false;
6947 /* A symbol is local if the user has said explicitly that it will be,
6948 or if we have a definition for the symbol. We cannot infer visibility
6949 for undefined symbols. */
6950 if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT
6951 && (TREE_CODE (exp) == FUNCTION_DECL
6952 || !extern_protected_data
6953 || DECL_VISIBILITY (exp) != VISIBILITY_PROTECTED)
6954 && (DECL_VISIBILITY_SPECIFIED (exp) || defined_locally))
6955 return true;
6957 /* If PIC, then assume that any global name can be overridden by
6958 symbols resolved from other modules. */
6959 if (shlib)
6960 return false;
6962 /* Variables defined outside this object might not be local. */
6963 if (DECL_EXTERNAL (exp) && !resolved_locally)
6964 return false;
6966 /* Non-dominant weak symbols are not defined locally. */
6967 if (DECL_WEAK (exp) && !resolved_locally)
6968 return false;
6970 /* Uninitialized COMMON variable may be unified with symbols
6971 resolved from other modules. */
6972 if (uninited_common && !resolved_locally)
6973 return false;
6975 /* Otherwise we're left with initialized (or non-common) global data
6976 which is of necessity defined locally. */
6977 return true;
6980 /* Assume ELF-ish defaults, since that's pretty much the most liberal
6981 wrt cross-module name binding. */
6983 bool
6984 default_binds_local_p (const_tree exp)
6986 return default_binds_local_p_3 (exp, flag_shlib != 0, true, false, false);
6989 /* Similar to default_binds_local_p, but common symbol may be local and
6990 extern protected data is non-local. */
6992 bool
6993 default_binds_local_p_2 (const_tree exp)
6995 return default_binds_local_p_3 (exp, flag_shlib != 0, true, true,
6996 !flag_pic);
6999 bool
7000 default_binds_local_p_1 (const_tree exp, int shlib)
7002 return default_binds_local_p_3 (exp, shlib != 0, false, false, false);
7005 /* Return true when references to DECL must bind to current definition in
7006 final executable.
7008 The condition is usually equivalent to whether the function binds to the
7009 current module (shared library or executable), that is to binds_local_p.
7010 We use this fact to avoid need for another target hook and implement
7011 the logic using binds_local_p and just special cases where
7012 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
7013 the weak definitions (that can be overwritten at linktime by other
7014 definition from different object file) and when resolution info is available
7015 we simply use the knowledge passed to us by linker plugin. */
7016 bool
7017 decl_binds_to_current_def_p (const_tree decl)
7019 gcc_assert (DECL_P (decl));
7020 if (!targetm.binds_local_p (decl))
7021 return false;
7022 if (!TREE_PUBLIC (decl))
7023 return true;
7025 /* When resolution is available, just use it. */
7026 if (symtab_node *node = symtab_node::get (decl))
7028 if (node->resolution != LDPR_UNKNOWN
7029 && !node->can_be_discarded_p ())
7030 return resolution_to_local_definition_p (node->resolution);
7033 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
7034 binds locally but still can be overwritten), DECL_COMMON (can be merged
7035 with a non-common definition somewhere in the same module) or
7036 DECL_EXTERNAL.
7037 This rely on fact that binds_local_p behave as decl_replaceable_p
7038 for all other declaration types. */
7039 if (DECL_WEAK (decl))
7040 return false;
7041 if (DECL_COMMON (decl)
7042 && (DECL_INITIAL (decl) == NULL
7043 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
7044 return false;
7045 if (DECL_EXTERNAL (decl))
7046 return false;
7047 return true;
7050 /* A replaceable function or variable is one which may be replaced
7051 at link-time with an entirely different definition, provided that the
7052 replacement has the same type. For example, functions declared
7053 with __attribute__((weak)) on most systems are replaceable.
7055 COMDAT functions are not replaceable, since all definitions of the
7056 function must be equivalent. It is important that COMDAT functions
7057 not be treated as replaceable so that use of C++ template
7058 instantiations is not penalized. */
7060 bool
7061 decl_replaceable_p (tree decl)
7063 gcc_assert (DECL_P (decl));
7064 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
7065 return false;
7066 if (!flag_semantic_interposition
7067 && !DECL_WEAK (decl))
7068 return false;
7069 return !decl_binds_to_current_def_p (decl);
7072 /* Default function to output code that will globalize a label. A
7073 target must define GLOBAL_ASM_OP or provide its own function to
7074 globalize a label. */
7075 #ifdef GLOBAL_ASM_OP
7076 void
7077 default_globalize_label (FILE * stream, const char *name)
7079 fputs (GLOBAL_ASM_OP, stream);
7080 assemble_name (stream, name);
7081 putc ('\n', stream);
7083 #endif /* GLOBAL_ASM_OP */
7085 /* Default function to output code that will globalize a declaration. */
7086 void
7087 default_globalize_decl_name (FILE * stream, tree decl)
7089 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
7090 targetm.asm_out.globalize_label (stream, name);
7093 /* Default function to output a label for unwind information. The
7094 default is to do nothing. A target that needs nonlocal labels for
7095 unwind information must provide its own function to do this. */
7096 void
7097 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
7098 tree decl ATTRIBUTE_UNUSED,
7099 int for_eh ATTRIBUTE_UNUSED,
7100 int empty ATTRIBUTE_UNUSED)
7104 /* Default function to output a label to divide up the exception table.
7105 The default is to do nothing. A target that needs/wants to divide
7106 up the table must provide it's own function to do this. */
7107 void
7108 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
7112 /* This is how to output an internal numbered label where PREFIX is
7113 the class of label and LABELNO is the number within the class. */
7115 void
7116 default_generate_internal_label (char *buf, const char *prefix,
7117 unsigned long labelno)
7119 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
7122 /* This is how to output an internal numbered label where PREFIX is
7123 the class of label and LABELNO is the number within the class. */
7125 void
7126 default_internal_label (FILE *stream, const char *prefix,
7127 unsigned long labelno)
7129 char *const buf = (char *) alloca (40 + strlen (prefix));
7130 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
7131 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
7135 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
7137 void
7138 default_asm_declare_constant_name (FILE *file, const char *name,
7139 const_tree exp ATTRIBUTE_UNUSED,
7140 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
7142 assemble_label (file, name);
7145 /* This is the default behavior at the beginning of a file. It's
7146 controlled by two other target-hook toggles. */
7147 void
7148 default_file_start (void)
7150 if (targetm.asm_file_start_app_off
7151 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
7152 fputs (ASM_APP_OFF, asm_out_file);
7154 if (targetm.asm_file_start_file_directive)
7156 /* LTO produced units have no meaningful main_input_filename. */
7157 if (in_lto_p)
7158 output_file_directive (asm_out_file, "<artificial>");
7159 else
7160 output_file_directive (asm_out_file, main_input_filename);
7164 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
7165 which emits a special section directive used to indicate whether or
7166 not this object file needs an executable stack. This is primarily
7167 a GNU extension to ELF but could be used on other targets. */
7169 int trampolines_created;
7171 void
7172 file_end_indicate_exec_stack (void)
7174 unsigned int flags = SECTION_DEBUG;
7175 if (trampolines_created)
7176 flags |= SECTION_CODE;
7178 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
7181 /* Emit a special section directive to indicate that this object file
7182 was compiled with -fsplit-stack. This is used to let the linker
7183 detect calls between split-stack code and non-split-stack code, so
7184 that it can modify the split-stack code to allocate a sufficiently
7185 large stack. We emit another special section if there are any
7186 functions in this file which have the no_split_stack attribute, to
7187 prevent the linker from warning about being unable to convert the
7188 functions if they call non-split-stack code. */
7190 void
7191 file_end_indicate_split_stack (void)
7193 if (flag_split_stack)
7195 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
7196 NULL));
7197 if (saw_no_split_stack)
7198 switch_to_section (get_section (".note.GNU-no-split-stack",
7199 SECTION_DEBUG, NULL));
7203 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
7204 a get_unnamed_section callback. */
7206 void
7207 output_section_asm_op (const void *directive)
7209 fprintf (asm_out_file, "%s\n", (const char *) directive);
7212 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
7213 the current section is NEW_SECTION. */
7215 void
7216 switch_to_section (section *new_section)
7218 if (in_section == new_section)
7219 return;
7221 if (new_section->common.flags & SECTION_FORGET)
7222 in_section = NULL;
7223 else
7224 in_section = new_section;
7226 switch (SECTION_STYLE (new_section))
7228 case SECTION_NAMED:
7229 targetm.asm_out.named_section (new_section->named.name,
7230 new_section->named.common.flags,
7231 new_section->named.decl);
7232 break;
7234 case SECTION_UNNAMED:
7235 new_section->unnamed.callback (new_section->unnamed.data);
7236 break;
7238 case SECTION_NOSWITCH:
7239 gcc_unreachable ();
7240 break;
7243 new_section->common.flags |= SECTION_DECLARED;
7246 /* If block symbol SYMBOL has not yet been assigned an offset, place
7247 it at the end of its block. */
7249 void
7250 place_block_symbol (rtx symbol)
7252 unsigned HOST_WIDE_INT size, mask, offset;
7253 struct constant_descriptor_rtx *desc;
7254 unsigned int alignment;
7255 struct object_block *block;
7256 tree decl;
7258 gcc_assert (SYMBOL_REF_BLOCK (symbol));
7259 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7260 return;
7262 /* Work out the symbol's size and alignment. */
7263 if (CONSTANT_POOL_ADDRESS_P (symbol))
7265 desc = SYMBOL_REF_CONSTANT (symbol);
7266 alignment = desc->align;
7267 size = GET_MODE_SIZE (desc->mode);
7269 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7271 decl = SYMBOL_REF_DECL (symbol);
7272 gcc_checking_assert (DECL_IN_CONSTANT_POOL (decl));
7273 alignment = DECL_ALIGN (decl);
7274 size = get_constant_size (DECL_INITIAL (decl));
7275 if ((flag_sanitize & SANITIZE_ADDRESS)
7276 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7277 && asan_protect_global (DECL_INITIAL (decl)))
7279 size += asan_red_zone_size (size);
7280 alignment = MAX (alignment,
7281 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7284 else
7286 struct symtab_node *snode;
7287 decl = SYMBOL_REF_DECL (symbol);
7289 snode = symtab_node::get (decl);
7290 if (snode->alias)
7292 rtx target = DECL_RTL (snode->ultimate_alias_target ()->decl);
7294 gcc_assert (MEM_P (target)
7295 && GET_CODE (XEXP (target, 0)) == SYMBOL_REF
7296 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (target, 0)));
7297 target = XEXP (target, 0);
7298 place_block_symbol (target);
7299 SYMBOL_REF_BLOCK_OFFSET (symbol) = SYMBOL_REF_BLOCK_OFFSET (target);
7300 return;
7302 alignment = get_variable_align (decl);
7303 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7304 if ((flag_sanitize & SANITIZE_ADDRESS)
7305 && asan_protect_global (decl))
7307 size += asan_red_zone_size (size);
7308 alignment = MAX (alignment,
7309 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7313 /* Calculate the object's offset from the start of the block. */
7314 block = SYMBOL_REF_BLOCK (symbol);
7315 mask = alignment / BITS_PER_UNIT - 1;
7316 offset = (block->size + mask) & ~mask;
7317 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7319 /* Record the block's new alignment and size. */
7320 block->alignment = MAX (block->alignment, alignment);
7321 block->size = offset + size;
7323 vec_safe_push (block->objects, symbol);
7326 /* Return the anchor that should be used to address byte offset OFFSET
7327 from the first object in BLOCK. MODEL is the TLS model used
7328 to access it. */
7331 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7332 enum tls_model model)
7334 char label[100];
7335 unsigned int begin, middle, end;
7336 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7337 rtx anchor;
7339 /* Work out the anchor's offset. Use an offset of 0 for the first
7340 anchor so that we don't pessimize the case where we take the address
7341 of a variable at the beginning of the block. This is particularly
7342 useful when a block has only one variable assigned to it.
7344 We try to place anchors RANGE bytes apart, so there can then be
7345 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7346 a ptr_mode offset. With some target settings, the lowest such
7347 anchor might be out of range for the lowest ptr_mode offset;
7348 likewise the highest anchor for the highest offset. Use anchors
7349 at the extreme ends of the ptr_mode range in such cases.
7351 All arithmetic uses unsigned integers in order to avoid
7352 signed overflow. */
7353 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7354 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7355 range = max_offset - min_offset + 1;
7356 if (range == 0)
7357 offset = 0;
7358 else
7360 bias = HOST_WIDE_INT_1U << (GET_MODE_BITSIZE (ptr_mode) - 1);
7361 if (offset < 0)
7363 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7364 delta -= delta % range;
7365 if (delta > bias)
7366 delta = bias;
7367 offset = (HOST_WIDE_INT) (-delta);
7369 else
7371 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7372 delta -= delta % range;
7373 if (delta > bias - 1)
7374 delta = bias - 1;
7375 offset = (HOST_WIDE_INT) delta;
7379 /* Do a binary search to see if there's already an anchor we can use.
7380 Set BEGIN to the new anchor's index if not. */
7381 begin = 0;
7382 end = vec_safe_length (block->anchors);
7383 while (begin != end)
7385 middle = (end + begin) / 2;
7386 anchor = (*block->anchors)[middle];
7387 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7388 end = middle;
7389 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7390 begin = middle + 1;
7391 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7392 end = middle;
7393 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7394 begin = middle + 1;
7395 else
7396 return anchor;
7399 /* Create a new anchor with a unique label. */
7400 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7401 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7402 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7403 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7405 /* Insert it at index BEGIN. */
7406 vec_safe_insert (block->anchors, begin, anchor);
7407 return anchor;
7410 /* Output the objects in BLOCK. */
7412 static void
7413 output_object_block (struct object_block *block)
7415 struct constant_descriptor_rtx *desc;
7416 unsigned int i;
7417 HOST_WIDE_INT offset;
7418 tree decl;
7419 rtx symbol;
7421 if (!block->objects)
7422 return;
7424 /* Switch to the section and make sure that the first byte is
7425 suitably aligned. */
7426 /* Special case VTV comdat sections similar to assemble_variable. */
7427 if (SECTION_STYLE (block->sect) == SECTION_NAMED
7428 && block->sect->named.name
7429 && (strcmp (block->sect->named.name, ".vtable_map_vars") == 0))
7430 handle_vtv_comdat_section (block->sect, block->sect->named.decl);
7431 else
7432 switch_to_section (block->sect);
7434 assemble_align (block->alignment);
7436 /* Define the values of all anchors relative to the current section
7437 position. */
7438 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7439 targetm.asm_out.output_anchor (symbol);
7441 /* Output the objects themselves. */
7442 offset = 0;
7443 FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7445 /* Move to the object's offset, padding with zeros if necessary. */
7446 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7447 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7448 if (CONSTANT_POOL_ADDRESS_P (symbol))
7450 desc = SYMBOL_REF_CONSTANT (symbol);
7451 /* Pass 1 for align as we have already laid out everything in the block.
7452 So aligning shouldn't be necessary. */
7453 output_constant_pool_1 (desc, 1);
7454 offset += GET_MODE_SIZE (desc->mode);
7456 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7458 HOST_WIDE_INT size;
7459 decl = SYMBOL_REF_DECL (symbol);
7460 assemble_constant_contents
7461 (DECL_INITIAL (decl), XSTR (symbol, 0), DECL_ALIGN (decl));
7463 size = get_constant_size (DECL_INITIAL (decl));
7464 offset += size;
7465 if ((flag_sanitize & SANITIZE_ADDRESS)
7466 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7467 && asan_protect_global (DECL_INITIAL (decl)))
7469 size = asan_red_zone_size (size);
7470 assemble_zeros (size);
7471 offset += size;
7474 else
7476 HOST_WIDE_INT size;
7477 decl = SYMBOL_REF_DECL (symbol);
7478 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7479 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7480 offset += size;
7481 if ((flag_sanitize & SANITIZE_ADDRESS)
7482 && asan_protect_global (decl))
7484 size = asan_red_zone_size (size);
7485 assemble_zeros (size);
7486 offset += size;
7492 /* A callback for qsort to compare object_blocks. */
7494 static int
7495 output_object_block_compare (const void *x, const void *y)
7497 object_block *p1 = *(object_block * const*)x;
7498 object_block *p2 = *(object_block * const*)y;
7500 if (p1->sect->common.flags & SECTION_NAMED
7501 && !(p2->sect->common.flags & SECTION_NAMED))
7502 return 1;
7504 if (!(p1->sect->common.flags & SECTION_NAMED)
7505 && p2->sect->common.flags & SECTION_NAMED)
7506 return -1;
7508 if (p1->sect->common.flags & SECTION_NAMED
7509 && p2->sect->common.flags & SECTION_NAMED)
7510 return strcmp (p1->sect->named.name, p2->sect->named.name);
7512 unsigned f1 = p1->sect->common.flags;
7513 unsigned f2 = p2->sect->common.flags;
7514 if (f1 == f2)
7515 return 0;
7516 return f1 < f2 ? -1 : 1;
7519 /* Output the definitions of all object_blocks. */
7521 void
7522 output_object_blocks (void)
7524 vec<object_block *, va_heap> v;
7525 v.create (object_block_htab->elements ());
7526 object_block *obj;
7527 hash_table<object_block_hasher>::iterator hi;
7529 FOR_EACH_HASH_TABLE_ELEMENT (*object_block_htab, obj, object_block *, hi)
7530 v.quick_push (obj);
7532 /* Sort them in order to output them in a deterministic manner,
7533 otherwise we may get .rodata sections in different orders with
7534 and without -g. */
7535 v.qsort (output_object_block_compare);
7536 unsigned i;
7537 FOR_EACH_VEC_ELT (v, i, obj)
7538 output_object_block (obj);
7540 v.release ();
7543 /* This function provides a possible implementation of the
7544 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7545 by -frecord-gcc-switches it creates a new mergeable, string section in the
7546 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7547 contains the switches in ASCII format.
7549 FIXME: This code does not correctly handle double quote characters
7550 that appear inside strings, (it strips them rather than preserving them).
7551 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7552 characters - instead it treats them as sub-string separators. Since
7553 we want to emit NUL strings terminators into the object file we have to use
7554 ASM_OUTPUT_SKIP. */
7557 elf_record_gcc_switches (print_switch_type type, const char * name)
7559 switch (type)
7561 case SWITCH_TYPE_PASSED:
7562 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7563 ASM_OUTPUT_SKIP (asm_out_file, HOST_WIDE_INT_1U);
7564 break;
7566 case SWITCH_TYPE_DESCRIPTIVE:
7567 if (name == NULL)
7569 /* Distinguish between invocations where name is NULL. */
7570 static bool started = false;
7572 if (!started)
7574 section * sec;
7576 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7577 SECTION_DEBUG
7578 | SECTION_MERGE
7579 | SECTION_STRINGS
7580 | (SECTION_ENTSIZE & 1),
7581 NULL);
7582 switch_to_section (sec);
7583 started = true;
7587 default:
7588 break;
7591 /* The return value is currently ignored by the caller, but must be 0.
7592 For -fverbose-asm the return value would be the number of characters
7593 emitted into the assembler file. */
7594 return 0;
7597 /* Emit text to declare externally defined symbols. It is needed to
7598 properly support non-default visibility. */
7599 void
7600 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7601 tree decl,
7602 const char *name ATTRIBUTE_UNUSED)
7604 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7605 set in order to avoid putting out names that are never really
7606 used. Always output visibility specified in the source. */
7607 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7608 && (DECL_VISIBILITY_SPECIFIED (decl)
7609 || targetm.binds_local_p (decl)))
7610 maybe_assemble_visibility (decl);
7613 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7615 void
7616 default_asm_output_source_filename (FILE *file, const char *name)
7618 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7619 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7620 #else
7621 fprintf (file, "\t.file\t");
7622 output_quoted_string (file, name);
7623 putc ('\n', file);
7624 #endif
7627 /* Output a file name in the form wanted by System V. */
7629 void
7630 output_file_directive (FILE *asm_file, const char *input_name)
7632 int len;
7633 const char *na;
7635 if (input_name == NULL)
7636 input_name = "<stdin>";
7637 else
7638 input_name = remap_debug_filename (input_name);
7640 len = strlen (input_name);
7641 na = input_name + len;
7643 /* NA gets INPUT_NAME sans directory names. */
7644 while (na > input_name)
7646 if (IS_DIR_SEPARATOR (na[-1]))
7647 break;
7648 na--;
7651 targetm.asm_out.output_source_filename (asm_file, na);
7654 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7655 EXP. */
7657 make_debug_expr_from_rtl (const_rtx exp)
7659 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7660 machine_mode mode = GET_MODE (exp);
7661 rtx dval;
7663 DECL_ARTIFICIAL (ddecl) = 1;
7664 if (REG_P (exp) && REG_EXPR (exp))
7665 type = TREE_TYPE (REG_EXPR (exp));
7666 else if (MEM_P (exp) && MEM_EXPR (exp))
7667 type = TREE_TYPE (MEM_EXPR (exp));
7668 else
7669 type = NULL_TREE;
7670 if (type && TYPE_MODE (type) == mode)
7671 TREE_TYPE (ddecl) = type;
7672 else
7673 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7674 SET_DECL_MODE (ddecl, mode);
7675 dval = gen_rtx_DEBUG_EXPR (mode);
7676 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7677 SET_DECL_RTL (ddecl, dval);
7678 return dval;
7681 #ifdef ELF_ASCII_ESCAPES
7682 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7684 void
7685 default_elf_asm_output_limited_string (FILE *f, const char *s)
7687 int escape;
7688 unsigned char c;
7690 fputs (STRING_ASM_OP, f);
7691 putc ('"', f);
7692 while (*s != '\0')
7694 c = *s;
7695 escape = ELF_ASCII_ESCAPES[c];
7696 switch (escape)
7698 case 0:
7699 putc (c, f);
7700 break;
7701 case 1:
7702 putc ('\\', f);
7703 putc ('0'+((c>>6)&7), f);
7704 putc ('0'+((c>>3)&7), f);
7705 putc ('0'+(c&7), f);
7706 break;
7707 default:
7708 putc ('\\', f);
7709 putc (escape, f);
7710 break;
7712 s++;
7714 putc ('\"', f);
7715 putc ('\n', f);
7718 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7720 void
7721 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7723 const char *limit = s + len;
7724 const char *last_null = NULL;
7725 unsigned bytes_in_chunk = 0;
7726 unsigned char c;
7727 int escape;
7729 for (; s < limit; s++)
7731 const char *p;
7733 if (bytes_in_chunk >= 60)
7735 putc ('\"', f);
7736 putc ('\n', f);
7737 bytes_in_chunk = 0;
7740 if (s > last_null)
7742 for (p = s; p < limit && *p != '\0'; p++)
7743 continue;
7744 last_null = p;
7746 else
7747 p = last_null;
7749 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7751 if (bytes_in_chunk > 0)
7753 putc ('\"', f);
7754 putc ('\n', f);
7755 bytes_in_chunk = 0;
7758 default_elf_asm_output_limited_string (f, s);
7759 s = p;
7761 else
7763 if (bytes_in_chunk == 0)
7764 fputs (ASCII_DATA_ASM_OP "\"", f);
7766 c = *s;
7767 escape = ELF_ASCII_ESCAPES[c];
7768 switch (escape)
7770 case 0:
7771 putc (c, f);
7772 bytes_in_chunk++;
7773 break;
7774 case 1:
7775 putc ('\\', f);
7776 putc ('0'+((c>>6)&7), f);
7777 putc ('0'+((c>>3)&7), f);
7778 putc ('0'+(c&7), f);
7779 bytes_in_chunk += 4;
7780 break;
7781 default:
7782 putc ('\\', f);
7783 putc (escape, f);
7784 bytes_in_chunk += 2;
7785 break;
7791 if (bytes_in_chunk > 0)
7793 putc ('\"', f);
7794 putc ('\n', f);
7797 #endif
7799 static GTY(()) section *elf_init_array_section;
7800 static GTY(()) section *elf_fini_array_section;
7802 static section *
7803 get_elf_initfini_array_priority_section (int priority,
7804 bool constructor_p)
7806 section *sec;
7807 if (priority != DEFAULT_INIT_PRIORITY)
7809 char buf[18];
7810 sprintf (buf, "%s.%.5u",
7811 constructor_p ? ".init_array" : ".fini_array",
7812 priority);
7813 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7815 else
7817 if (constructor_p)
7819 if (elf_init_array_section == NULL)
7820 elf_init_array_section
7821 = get_section (".init_array",
7822 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7823 sec = elf_init_array_section;
7825 else
7827 if (elf_fini_array_section == NULL)
7828 elf_fini_array_section
7829 = get_section (".fini_array",
7830 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7831 sec = elf_fini_array_section;
7834 return sec;
7837 /* Use .init_array section for constructors. */
7839 void
7840 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7842 section *sec = get_elf_initfini_array_priority_section (priority,
7843 true);
7844 assemble_addr_to_section (symbol, sec);
7847 /* Use .fini_array section for destructors. */
7849 void
7850 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7852 section *sec = get_elf_initfini_array_priority_section (priority,
7853 false);
7854 assemble_addr_to_section (symbol, sec);
7857 /* Default TARGET_ASM_OUTPUT_IDENT hook.
7859 This is a bit of a cheat. The real default is a no-op, but this
7860 hook is the default for all targets with a .ident directive. */
7862 void
7863 default_asm_output_ident_directive (const char *ident_str)
7865 const char *ident_asm_op = "\t.ident\t";
7867 /* If we are still in the front end, do not write out the string
7868 to asm_out_file. Instead, add a fake top-level asm statement.
7869 This allows the front ends to use this hook without actually
7870 writing to asm_out_file, to handle #ident or Pragma Ident. */
7871 if (symtab->state == PARSING)
7873 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
7874 symtab->finalize_toplevel_asm (build_string (strlen (buf), buf));
7876 else
7877 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
7881 /* This function ensures that vtable_map variables are not only
7882 in the comdat section, but that each variable has its own unique
7883 comdat name. Without this the variables end up in the same section
7884 with a single comdat name.
7886 FIXME: resolve_unique_section needs to deal better with
7887 decls with both DECL_SECTION_NAME and DECL_ONE_ONLY. Once
7888 that is fixed, this if-else statement can be replaced with
7889 a single call to "switch_to_section (sect)". */
7891 static void
7892 handle_vtv_comdat_section (section *sect, const_tree decl ATTRIBUTE_UNUSED)
7894 #if defined (OBJECT_FORMAT_ELF)
7895 targetm.asm_out.named_section (sect->named.name,
7896 sect->named.common.flags
7897 | SECTION_LINKONCE,
7898 DECL_NAME (decl));
7899 in_section = sect;
7900 #else
7901 /* Neither OBJECT_FORMAT_PE, nor OBJECT_FORMAT_COFF is set here.
7902 Therefore the following check is used.
7903 In case a the target is PE or COFF a comdat group section
7904 is created, e.g. .vtable_map_vars$foo. The linker places
7905 everything in .vtable_map_vars at the end.
7907 A fix could be made in
7908 gcc/config/i386/winnt.c: i386_pe_unique_section. */
7909 if (TARGET_PECOFF)
7911 char *name;
7913 if (TREE_CODE (DECL_NAME (decl)) == IDENTIFIER_NODE)
7914 name = ACONCAT ((sect->named.name, "$",
7915 IDENTIFIER_POINTER (DECL_NAME (decl)), NULL));
7916 else
7917 name = ACONCAT ((sect->named.name, "$",
7918 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (DECL_NAME (decl))),
7919 NULL));
7921 targetm.asm_out.named_section (name,
7922 sect->named.common.flags
7923 | SECTION_LINKONCE,
7924 DECL_NAME (decl));
7925 in_section = sect;
7927 else
7928 switch_to_section (sect);
7929 #endif
7932 #include "gt-varasm.h"