PR middle-end/82875
[official-gcc.git] / gcc / varasm.c
blob923399d71a46ff6858f4c9d1f62f265af222531e
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 "stringpool.h"
55 #include "attribs.h"
56 #include "asan.h"
57 #include "rtl-iter.h"
59 #ifdef XCOFF_DEBUGGING_INFO
60 #include "xcoffout.h" /* Needed for external data declarations. */
61 #endif
63 /* The (assembler) name of the first globally-visible object output. */
64 extern GTY(()) const char *first_global_object_name;
65 extern GTY(()) const char *weak_global_object_name;
67 const char *first_global_object_name;
68 const char *weak_global_object_name;
70 struct addr_const;
71 struct constant_descriptor_rtx;
72 struct rtx_constant_pool;
74 #define n_deferred_constants (crtl->varasm.deferred_constants)
76 /* Number for making the label on the next
77 constant that is stored in memory. */
79 static GTY(()) int const_labelno;
81 /* Carry information from ASM_DECLARE_OBJECT_NAME
82 to ASM_FINISH_DECLARE_OBJECT. */
84 int size_directive_output;
86 /* The last decl for which assemble_variable was called,
87 if it did ASM_DECLARE_OBJECT_NAME.
88 If the last call to assemble_variable didn't do that,
89 this holds 0. */
91 tree last_assemble_variable_decl;
93 /* The following global variable indicates if the first basic block
94 in a function belongs to the cold partition or not. */
96 bool first_function_block_is_cold;
98 /* Whether we saw any functions with no_split_stack. */
100 static bool saw_no_split_stack;
102 static const char *strip_reg_name (const char *);
103 static int contains_pointers_p (tree);
104 #ifdef ASM_OUTPUT_EXTERNAL
105 static bool incorporeal_function_p (tree);
106 #endif
107 static void decode_addr_const (tree, struct addr_const *);
108 static hashval_t const_hash_1 (const tree);
109 static int compare_constant (const tree, const tree);
110 static void output_constant_def_contents (rtx);
111 static void output_addressed_constants (tree);
112 static unsigned HOST_WIDE_INT output_constant (tree, unsigned HOST_WIDE_INT,
113 unsigned int, bool);
114 static void globalize_decl (tree);
115 static bool decl_readonly_section_1 (enum section_category);
116 #ifdef BSS_SECTION_ASM_OP
117 #ifdef ASM_OUTPUT_ALIGNED_BSS
118 static void asm_output_aligned_bss (FILE *, tree, const char *,
119 unsigned HOST_WIDE_INT, int)
120 ATTRIBUTE_UNUSED;
121 #endif
122 #endif /* BSS_SECTION_ASM_OP */
123 static void mark_weak (tree);
124 static void output_constant_pool (const char *, tree);
125 static void handle_vtv_comdat_section (section *, const_tree);
127 /* Well-known sections, each one associated with some sort of *_ASM_OP. */
128 section *text_section;
129 section *data_section;
130 section *readonly_data_section;
131 section *sdata_section;
132 section *ctors_section;
133 section *dtors_section;
134 section *bss_section;
135 section *sbss_section;
137 /* Various forms of common section. All are guaranteed to be nonnull. */
138 section *tls_comm_section;
139 section *comm_section;
140 section *lcomm_section;
142 /* A SECTION_NOSWITCH section used for declaring global BSS variables.
143 May be null. */
144 section *bss_noswitch_section;
146 /* The section that holds the main exception table, when known. The section
147 is set either by the target's init_sections hook or by the first call to
148 switch_to_exception_section. */
149 section *exception_section;
151 /* The section that holds the DWARF2 frame unwind information, when known.
152 The section is set either by the target's init_sections hook or by the
153 first call to switch_to_eh_frame_section. */
154 section *eh_frame_section;
156 /* asm_out_file's current section. This is NULL if no section has yet
157 been selected or if we lose track of what the current section is. */
158 section *in_section;
160 /* True if code for the current function is currently being directed
161 at the cold section. */
162 bool in_cold_section_p;
164 /* The following global holds the "function name" for the code in the
165 cold section of a function, if hot/cold function splitting is enabled
166 and there was actually code that went into the cold section. A
167 pseudo function name is needed for the cold section of code for some
168 debugging tools that perform symbolization. */
169 tree cold_function_name = NULL_TREE;
171 /* A linked list of all the unnamed sections. */
172 static GTY(()) section *unnamed_sections;
174 /* Return a nonzero value if DECL has a section attribute. */
175 #define IN_NAMED_SECTION(DECL) \
176 (VAR_OR_FUNCTION_DECL_P (DECL) && DECL_SECTION_NAME (DECL) != NULL)
178 struct section_hasher : ggc_ptr_hash<section>
180 typedef const char *compare_type;
182 static hashval_t hash (section *);
183 static bool equal (section *, const char *);
186 /* Hash table of named sections. */
187 static GTY(()) hash_table<section_hasher> *section_htab;
189 struct object_block_hasher : ggc_ptr_hash<object_block>
191 typedef const section *compare_type;
193 static hashval_t hash (object_block *);
194 static bool equal (object_block *, const section *);
197 /* A table of object_blocks, indexed by section. */
198 static GTY(()) hash_table<object_block_hasher> *object_block_htab;
200 /* The next number to use for internal anchor labels. */
201 static GTY(()) int anchor_labelno;
203 /* A pool of constants that can be shared between functions. */
204 static GTY(()) struct rtx_constant_pool *shared_constant_pool;
206 /* Helper routines for maintaining section_htab. */
208 bool
209 section_hasher::equal (section *old, const char *new_name)
211 return strcmp (old->named.name, new_name) == 0;
214 hashval_t
215 section_hasher::hash (section *old)
217 return htab_hash_string (old->named.name);
220 /* Return a hash value for section SECT. */
222 static hashval_t
223 hash_section (section *sect)
225 if (sect->common.flags & SECTION_NAMED)
226 return htab_hash_string (sect->named.name);
227 return sect->common.flags;
230 /* Helper routines for maintaining object_block_htab. */
232 inline bool
233 object_block_hasher::equal (object_block *old, const section *new_section)
235 return old->sect == new_section;
238 hashval_t
239 object_block_hasher::hash (object_block *old)
241 return hash_section (old->sect);
244 /* Return a new unnamed section with the given fields. */
246 section *
247 get_unnamed_section (unsigned int flags, void (*callback) (const void *),
248 const void *data)
250 section *sect;
252 sect = ggc_alloc<section> ();
253 sect->unnamed.common.flags = flags | SECTION_UNNAMED;
254 sect->unnamed.callback = callback;
255 sect->unnamed.data = data;
256 sect->unnamed.next = unnamed_sections;
258 unnamed_sections = sect;
259 return sect;
262 /* Return a SECTION_NOSWITCH section with the given fields. */
264 static section *
265 get_noswitch_section (unsigned int flags, noswitch_section_callback callback)
267 section *sect;
269 sect = ggc_alloc<section> ();
270 sect->noswitch.common.flags = flags | SECTION_NOSWITCH;
271 sect->noswitch.callback = callback;
273 return sect;
276 /* Return the named section structure associated with NAME. Create
277 a new section with the given fields if no such structure exists. */
279 section *
280 get_section (const char *name, unsigned int flags, tree decl)
282 section *sect, **slot;
284 slot = section_htab->find_slot_with_hash (name, htab_hash_string (name),
285 INSERT);
286 flags |= SECTION_NAMED;
287 if (*slot == NULL)
289 sect = ggc_alloc<section> ();
290 sect->named.common.flags = flags;
291 sect->named.name = ggc_strdup (name);
292 sect->named.decl = decl;
293 *slot = sect;
295 else
297 sect = *slot;
298 if ((sect->common.flags & ~SECTION_DECLARED) != flags
299 && ((sect->common.flags | flags) & SECTION_OVERRIDE) == 0)
301 /* It is fine if one of the section flags is
302 SECTION_WRITE | SECTION_RELRO and the other has none of these
303 flags (i.e. read-only) in named sections and either the
304 section hasn't been declared yet or has been declared as writable.
305 In that case just make sure the resulting flags are
306 SECTION_WRITE | SECTION_RELRO, ie. writable only because of
307 relocations. */
308 if (((sect->common.flags ^ flags) & (SECTION_WRITE | SECTION_RELRO))
309 == (SECTION_WRITE | SECTION_RELRO)
310 && (sect->common.flags
311 & ~(SECTION_DECLARED | SECTION_WRITE | SECTION_RELRO))
312 == (flags & ~(SECTION_WRITE | SECTION_RELRO))
313 && ((sect->common.flags & SECTION_DECLARED) == 0
314 || (sect->common.flags & SECTION_WRITE)))
316 sect->common.flags |= (SECTION_WRITE | SECTION_RELRO);
317 return sect;
319 /* Sanity check user variables for flag changes. */
320 if (sect->named.decl != NULL
321 && DECL_P (sect->named.decl)
322 && decl != sect->named.decl)
324 if (decl != NULL && DECL_P (decl))
325 error ("%+qD causes a section type conflict with %qD",
326 decl, sect->named.decl);
327 else
328 error ("section type conflict with %qD", sect->named.decl);
329 inform (DECL_SOURCE_LOCATION (sect->named.decl),
330 "%qD was declared here", sect->named.decl);
332 else if (decl != NULL && DECL_P (decl))
333 error ("%+qD causes a section type conflict", decl);
334 else
335 error ("section type conflict");
336 /* Make sure we don't error about one section multiple times. */
337 sect->common.flags |= SECTION_OVERRIDE;
340 return sect;
343 /* Return true if the current compilation mode benefits from having
344 objects grouped into blocks. */
346 static bool
347 use_object_blocks_p (void)
349 return flag_section_anchors;
352 /* Return the object_block structure for section SECT. Create a new
353 structure if we haven't created one already. Return null if SECT
354 itself is null. */
356 static struct object_block *
357 get_block_for_section (section *sect)
359 struct object_block *block;
361 if (sect == NULL)
362 return NULL;
364 object_block **slot
365 = object_block_htab->find_slot_with_hash (sect, hash_section (sect),
366 INSERT);
367 block = *slot;
368 if (block == NULL)
370 block = ggc_cleared_alloc<object_block> ();
371 block->sect = sect;
372 *slot = block;
374 return block;
377 /* Create a symbol with label LABEL and place it at byte offset
378 OFFSET in BLOCK. OFFSET can be negative if the symbol's offset
379 is not yet known. LABEL must be a garbage-collected string. */
381 static rtx
382 create_block_symbol (const char *label, struct object_block *block,
383 HOST_WIDE_INT offset)
385 rtx symbol;
386 unsigned int size;
388 /* Create the extended SYMBOL_REF. */
389 size = RTX_HDR_SIZE + sizeof (struct block_symbol);
390 symbol = (rtx) ggc_internal_alloc (size);
392 /* Initialize the normal SYMBOL_REF fields. */
393 memset (symbol, 0, size);
394 PUT_CODE (symbol, SYMBOL_REF);
395 PUT_MODE (symbol, Pmode);
396 XSTR (symbol, 0) = label;
397 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_HAS_BLOCK_INFO;
399 /* Initialize the block_symbol stuff. */
400 SYMBOL_REF_BLOCK (symbol) = block;
401 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
403 return symbol;
406 /* Return a section with a particular name and with whatever SECTION_*
407 flags section_type_flags deems appropriate. The name of the section
408 is taken from NAME if nonnull, otherwise it is taken from DECL's
409 DECL_SECTION_NAME. DECL is the decl associated with the section
410 (see the section comment for details) and RELOC is as for
411 section_type_flags. */
413 section *
414 get_named_section (tree decl, const char *name, int reloc)
416 unsigned int flags;
418 if (name == NULL)
420 gcc_assert (decl && DECL_P (decl) && DECL_SECTION_NAME (decl));
421 name = DECL_SECTION_NAME (decl);
424 flags = targetm.section_type_flags (decl, name, reloc);
425 return get_section (name, flags, decl);
428 /* Worker for resolve_unique_section. */
430 static bool
431 set_implicit_section (struct symtab_node *n, void *data ATTRIBUTE_UNUSED)
433 n->implicit_section = true;
434 return false;
437 /* If required, set DECL_SECTION_NAME to a unique name. */
439 void
440 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
441 int flag_function_or_data_sections)
443 if (DECL_SECTION_NAME (decl) == NULL
444 && targetm_common.have_named_sections
445 && (flag_function_or_data_sections
446 || DECL_COMDAT_GROUP (decl)))
448 targetm.asm_out.unique_section (decl, reloc);
449 if (DECL_SECTION_NAME (decl))
450 symtab_node::get (decl)->call_for_symbol_and_aliases
451 (set_implicit_section, NULL, true);
455 #ifdef BSS_SECTION_ASM_OP
457 #ifdef ASM_OUTPUT_ALIGNED_BSS
459 /* Utility function for targets to use in implementing
460 ASM_OUTPUT_ALIGNED_BSS.
461 ??? It is believed that this function will work in most cases so such
462 support is localized here. */
464 static void
465 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
466 const char *name, unsigned HOST_WIDE_INT size,
467 int align)
469 switch_to_section (bss_section);
470 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
471 #ifdef ASM_DECLARE_OBJECT_NAME
472 last_assemble_variable_decl = decl;
473 ASM_DECLARE_OBJECT_NAME (file, name, decl);
474 #else
475 /* Standard thing is just output label for the object. */
476 ASM_OUTPUT_LABEL (file, name);
477 #endif /* ASM_DECLARE_OBJECT_NAME */
478 ASM_OUTPUT_SKIP (file, size ? size : 1);
481 #endif
483 #endif /* BSS_SECTION_ASM_OP */
485 #ifndef USE_SELECT_SECTION_FOR_FUNCTIONS
486 /* Return the hot section for function DECL. Return text_section for
487 null DECLs. */
489 static section *
490 hot_function_section (tree decl)
492 if (decl != NULL_TREE
493 && DECL_SECTION_NAME (decl) != NULL
494 && targetm_common.have_named_sections)
495 return get_named_section (decl, NULL, 0);
496 else
497 return text_section;
499 #endif
501 /* Return section for TEXT_SECTION_NAME if DECL or DECL_SECTION_NAME (DECL)
502 is NULL.
504 When DECL_SECTION_NAME is non-NULL and it is implicit section and
505 NAMED_SECTION_SUFFIX is non-NULL, then produce section called
506 concatenate the name with NAMED_SECTION_SUFFIX.
507 Otherwise produce "TEXT_SECTION_NAME.IMPLICIT_NAME". */
509 section *
510 get_named_text_section (tree decl,
511 const char *text_section_name,
512 const char *named_section_suffix)
514 if (decl && DECL_SECTION_NAME (decl))
516 if (named_section_suffix)
518 const char *dsn = DECL_SECTION_NAME (decl);
519 const char *stripped_name;
520 char *name, *buffer;
522 name = (char *) alloca (strlen (dsn) + 1);
523 memcpy (name, dsn,
524 strlen (dsn) + 1);
526 stripped_name = targetm.strip_name_encoding (name);
528 buffer = ACONCAT ((stripped_name, named_section_suffix, NULL));
529 return get_named_section (decl, buffer, 0);
531 else if (symtab_node::get (decl)->implicit_section)
533 const char *name;
535 /* Do not try to split gnu_linkonce functions. This gets somewhat
536 slipperly. */
537 if (DECL_COMDAT_GROUP (decl) && !HAVE_COMDAT_GROUP)
538 return NULL;
539 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
540 name = targetm.strip_name_encoding (name);
541 return get_named_section (decl, ACONCAT ((text_section_name, ".",
542 name, NULL)), 0);
544 else
545 return NULL;
547 return get_named_section (decl, text_section_name, 0);
550 /* Choose named function section based on its frequency. */
552 section *
553 default_function_section (tree decl, enum node_frequency freq,
554 bool startup, bool exit)
556 #if defined HAVE_LD_EH_GC_SECTIONS && defined HAVE_LD_EH_GC_SECTIONS_BUG
557 /* Old GNU linkers have buggy --gc-section support, which sometimes
558 results in .gcc_except_table* sections being garbage collected. */
559 if (decl
560 && symtab_node::get (decl)->implicit_section)
561 return NULL;
562 #endif
564 if (!flag_reorder_functions
565 || !targetm_common.have_named_sections)
566 return NULL;
567 /* Startup code should go to startup subsection unless it is
568 unlikely executed (this happens especially with function splitting
569 where we can split away unnecessary parts of static constructors. */
570 if (startup && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
572 /* If we do have a profile or(and) LTO phase is executed, we do not need
573 these ELF section. */
574 if (!in_lto_p || !flag_profile_values)
575 return get_named_text_section (decl, ".text.startup", NULL);
576 else
577 return NULL;
580 /* Similarly for exit. */
581 if (exit && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
582 return get_named_text_section (decl, ".text.exit", NULL);
584 /* Group cold functions together, similarly for hot code. */
585 switch (freq)
587 case NODE_FREQUENCY_UNLIKELY_EXECUTED:
588 return get_named_text_section (decl, ".text.unlikely", NULL);
589 case NODE_FREQUENCY_HOT:
590 /* If we do have a profile or(and) LTO phase is executed, we do not need
591 these ELF section. */
592 if (!in_lto_p || !flag_profile_values)
593 return get_named_text_section (decl, ".text.hot", NULL);
594 /* FALLTHRU */
595 default:
596 return NULL;
600 /* Return the section for function DECL.
602 If DECL is NULL_TREE, return the text section. We can be passed
603 NULL_TREE under some circumstances by dbxout.c at least.
605 If FORCE_COLD is true, return cold function section ignoring
606 the frequency info of cgraph_node. */
608 static section *
609 function_section_1 (tree decl, bool force_cold)
611 section *section = NULL;
612 enum node_frequency freq = NODE_FREQUENCY_NORMAL;
613 bool startup = false, exit = false;
615 if (decl)
617 struct cgraph_node *node = cgraph_node::get (decl);
619 if (node)
621 freq = node->frequency;
622 startup = node->only_called_at_startup;
623 exit = node->only_called_at_exit;
626 if (force_cold)
627 freq = NODE_FREQUENCY_UNLIKELY_EXECUTED;
629 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
630 if (decl != NULL_TREE
631 && DECL_SECTION_NAME (decl) != NULL)
633 if (targetm.asm_out.function_section)
634 section = targetm.asm_out.function_section (decl, freq,
635 startup, exit);
636 if (section)
637 return section;
638 return get_named_section (decl, NULL, 0);
640 else
641 return targetm.asm_out.select_section
642 (decl, freq == NODE_FREQUENCY_UNLIKELY_EXECUTED,
643 symtab_node::get (decl)->definition_alignment ());
644 #else
645 if (targetm.asm_out.function_section)
646 section = targetm.asm_out.function_section (decl, freq, startup, exit);
647 if (section)
648 return section;
649 return hot_function_section (decl);
650 #endif
653 /* Return the section for function DECL.
655 If DECL is NULL_TREE, return the text section. We can be passed
656 NULL_TREE under some circumstances by dbxout.c at least. */
658 section *
659 function_section (tree decl)
661 /* Handle cases where function splitting code decides
662 to put function entry point into unlikely executed section
663 despite the fact that the function itself is not cold
664 (i.e. it is called rarely but contains a hot loop that is
665 better to live in hot subsection for the code locality). */
666 return function_section_1 (decl,
667 first_function_block_is_cold);
670 /* Return the section for the current function, take IN_COLD_SECTION_P
671 into account. */
673 section *
674 current_function_section (void)
676 return function_section_1 (current_function_decl, in_cold_section_p);
679 /* Tell assembler to switch to unlikely-to-be-executed text section. */
681 section *
682 unlikely_text_section (void)
684 return function_section_1 (current_function_decl, true);
687 /* When called within a function context, return true if the function
688 has been assigned a cold text section and if SECT is that section.
689 When called outside a function context, return true if SECT is the
690 default cold section. */
692 bool
693 unlikely_text_section_p (section *sect)
695 return sect == function_section_1 (current_function_decl, true);
698 /* Switch to the other function partition (if inside of hot section
699 into cold section, otherwise into the hot section). */
701 void
702 switch_to_other_text_partition (void)
704 in_cold_section_p = !in_cold_section_p;
705 switch_to_section (current_function_section ());
708 /* Return the read-only data section associated with function DECL. */
710 section *
711 default_function_rodata_section (tree decl)
713 if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
715 const char *name = DECL_SECTION_NAME (decl);
717 if (DECL_COMDAT_GROUP (decl) && HAVE_COMDAT_GROUP)
719 const char *dot;
720 size_t len;
721 char* rname;
723 dot = strchr (name + 1, '.');
724 if (!dot)
725 dot = name;
726 len = strlen (dot) + 8;
727 rname = (char *) alloca (len);
729 strcpy (rname, ".rodata");
730 strcat (rname, dot);
731 return get_section (rname, SECTION_LINKONCE, decl);
733 /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo. */
734 else if (DECL_COMDAT_GROUP (decl)
735 && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
737 size_t len = strlen (name) + 1;
738 char *rname = (char *) alloca (len);
740 memcpy (rname, name, len);
741 rname[14] = 'r';
742 return get_section (rname, SECTION_LINKONCE, decl);
744 /* For .text.foo we want to use .rodata.foo. */
745 else if (flag_function_sections && flag_data_sections
746 && strncmp (name, ".text.", 6) == 0)
748 size_t len = strlen (name) + 1;
749 char *rname = (char *) alloca (len + 2);
751 memcpy (rname, ".rodata", 7);
752 memcpy (rname + 7, name + 5, len - 5);
753 return get_section (rname, 0, decl);
757 return readonly_data_section;
760 /* Return the read-only data section associated with function DECL
761 for targets where that section should be always the single
762 readonly data section. */
764 section *
765 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
767 return readonly_data_section;
770 /* A subroutine of mergeable_string_section and mergeable_constant_section. */
772 static const char *
773 function_mergeable_rodata_prefix (void)
775 section *s = targetm.asm_out.function_rodata_section (current_function_decl);
776 if (SECTION_STYLE (s) == SECTION_NAMED)
777 return s->named.name;
778 else
779 return targetm.asm_out.mergeable_rodata_prefix;
782 /* Return the section to use for string merging. */
784 static section *
785 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
786 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
787 unsigned int flags ATTRIBUTE_UNUSED)
789 HOST_WIDE_INT len;
791 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
792 && TREE_CODE (decl) == STRING_CST
793 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
794 && align <= 256
795 && (len = int_size_in_bytes (TREE_TYPE (decl))) > 0
796 && TREE_STRING_LENGTH (decl) >= len)
798 scalar_int_mode mode;
799 unsigned int modesize;
800 const char *str;
801 HOST_WIDE_INT i;
802 int j, unit;
803 const char *prefix = function_mergeable_rodata_prefix ();
804 char *name = (char *) alloca (strlen (prefix) + 30);
806 mode = SCALAR_INT_TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
807 modesize = GET_MODE_BITSIZE (mode);
808 if (modesize >= 8 && modesize <= 256
809 && (modesize & (modesize - 1)) == 0)
811 if (align < modesize)
812 align = modesize;
814 str = TREE_STRING_POINTER (decl);
815 unit = GET_MODE_SIZE (mode);
817 /* Check for embedded NUL characters. */
818 for (i = 0; i < len; i += unit)
820 for (j = 0; j < unit; j++)
821 if (str[i + j] != '\0')
822 break;
823 if (j == unit)
824 break;
826 if (i == len - unit)
828 sprintf (name, "%s.str%d.%d", prefix,
829 modesize / 8, (int) (align / 8));
830 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
831 return get_section (name, flags, NULL);
836 return readonly_data_section;
839 /* Return the section to use for constant merging. */
841 section *
842 mergeable_constant_section (machine_mode mode ATTRIBUTE_UNUSED,
843 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
844 unsigned int flags ATTRIBUTE_UNUSED)
846 unsigned int modesize = GET_MODE_BITSIZE (mode);
848 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
849 && mode != VOIDmode
850 && mode != BLKmode
851 && modesize <= align
852 && align >= 8
853 && align <= 256
854 && (align & (align - 1)) == 0)
856 const char *prefix = function_mergeable_rodata_prefix ();
857 char *name = (char *) alloca (strlen (prefix) + 30);
859 sprintf (name, "%s.cst%d", prefix, (int) (align / 8));
860 flags |= (align / 8) | SECTION_MERGE;
861 return get_section (name, flags, NULL);
863 return readonly_data_section;
866 /* Given NAME, a putative register name, discard any customary prefixes. */
868 static const char *
869 strip_reg_name (const char *name)
871 #ifdef REGISTER_PREFIX
872 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
873 name += strlen (REGISTER_PREFIX);
874 #endif
875 if (name[0] == '%' || name[0] == '#')
876 name++;
877 return name;
880 /* The user has asked for a DECL to have a particular name. Set (or
881 change) it in such a way that we don't prefix an underscore to
882 it. */
883 void
884 set_user_assembler_name (tree decl, const char *name)
886 char *starred = (char *) alloca (strlen (name) + 2);
887 starred[0] = '*';
888 strcpy (starred + 1, name);
889 symtab->change_decl_assembler_name (decl, get_identifier (starred));
890 SET_DECL_RTL (decl, NULL_RTX);
893 /* Decode an `asm' spec for a declaration as a register name.
894 Return the register number, or -1 if nothing specified,
895 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
896 or -3 if ASMSPEC is `cc' and is not recognized,
897 or -4 if ASMSPEC is `memory' and is not recognized.
898 Accept an exact spelling or a decimal number.
899 Prefixes such as % are optional. */
902 decode_reg_name_and_count (const char *asmspec, int *pnregs)
904 /* Presume just one register is clobbered. */
905 *pnregs = 1;
907 if (asmspec != 0)
909 int i;
911 /* Get rid of confusing prefixes. */
912 asmspec = strip_reg_name (asmspec);
914 /* Allow a decimal number as a "register name". */
915 for (i = strlen (asmspec) - 1; i >= 0; i--)
916 if (! ISDIGIT (asmspec[i]))
917 break;
918 if (asmspec[0] != 0 && i < 0)
920 i = atoi (asmspec);
921 if (i < FIRST_PSEUDO_REGISTER && i >= 0 && reg_names[i][0])
922 return i;
923 else
924 return -2;
927 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
928 if (reg_names[i][0]
929 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
930 return i;
932 #ifdef OVERLAPPING_REGISTER_NAMES
934 static const struct
936 const char *const name;
937 const int number;
938 const int nregs;
939 } table[] = OVERLAPPING_REGISTER_NAMES;
941 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
942 if (table[i].name[0]
943 && ! strcmp (asmspec, table[i].name))
945 *pnregs = table[i].nregs;
946 return table[i].number;
949 #endif /* OVERLAPPING_REGISTER_NAMES */
951 #ifdef ADDITIONAL_REGISTER_NAMES
953 static const struct { const char *const name; const int number; } table[]
954 = ADDITIONAL_REGISTER_NAMES;
956 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
957 if (table[i].name[0]
958 && ! strcmp (asmspec, table[i].name)
959 && reg_names[table[i].number][0])
960 return table[i].number;
962 #endif /* ADDITIONAL_REGISTER_NAMES */
964 if (!strcmp (asmspec, "memory"))
965 return -4;
967 if (!strcmp (asmspec, "cc"))
968 return -3;
970 return -2;
973 return -1;
977 decode_reg_name (const char *name)
979 int count;
980 return decode_reg_name_and_count (name, &count);
984 /* Return true if DECL's initializer is suitable for a BSS section. */
986 bool
987 bss_initializer_p (const_tree decl)
989 /* Do not put constants into the .bss section, they belong in a readonly
990 section. */
991 return (!TREE_READONLY (decl)
992 && (DECL_INITIAL (decl) == NULL
993 /* In LTO we have no errors in program; error_mark_node is used
994 to mark offlined constructors. */
995 || (DECL_INITIAL (decl) == error_mark_node
996 && !in_lto_p)
997 || (flag_zero_initialized_in_bss
998 && initializer_zerop (DECL_INITIAL (decl)))));
1001 /* Compute the alignment of variable specified by DECL.
1002 DONT_OUTPUT_DATA is from assemble_variable. */
1004 void
1005 align_variable (tree decl, bool dont_output_data)
1007 unsigned int align = DECL_ALIGN (decl);
1009 /* In the case for initialing an array whose length isn't specified,
1010 where we have not yet been able to do the layout,
1011 figure out the proper alignment now. */
1012 if (dont_output_data && DECL_SIZE (decl) == 0
1013 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
1014 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
1016 /* Some object file formats have a maximum alignment which they support.
1017 In particular, a.out format supports a maximum alignment of 4. */
1018 if (align > MAX_OFILE_ALIGNMENT)
1020 error ("alignment of %q+D is greater than maximum object "
1021 "file alignment %d", decl,
1022 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
1023 align = MAX_OFILE_ALIGNMENT;
1026 if (! DECL_USER_ALIGN (decl))
1028 #ifdef DATA_ABI_ALIGNMENT
1029 unsigned int data_abi_align
1030 = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1031 /* For backwards compatibility, don't assume the ABI alignment for
1032 TLS variables. */
1033 if (! DECL_THREAD_LOCAL_P (decl) || data_abi_align <= BITS_PER_WORD)
1034 align = data_abi_align;
1035 #endif
1037 /* On some machines, it is good to increase alignment sometimes.
1038 But as DECL_ALIGN is used both for actually emitting the variable
1039 and for code accessing the variable as guaranteed alignment, we
1040 can only increase the alignment if it is a performance optimization
1041 if the references to it must bind to the current definition. */
1042 if (decl_binds_to_current_def_p (decl)
1043 && !DECL_VIRTUAL_P (decl))
1045 #ifdef DATA_ALIGNMENT
1046 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1047 /* Don't increase alignment too much for TLS variables - TLS space
1048 is too precious. */
1049 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1050 align = data_align;
1051 #endif
1052 if (DECL_INITIAL (decl) != 0
1053 /* In LTO we have no errors in program; error_mark_node is used
1054 to mark offlined constructors. */
1055 && (in_lto_p || DECL_INITIAL (decl) != error_mark_node))
1057 unsigned int const_align
1058 = targetm.constant_alignment (DECL_INITIAL (decl), align);
1059 /* Don't increase alignment too much for TLS variables - TLS
1060 space is too precious. */
1061 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1062 align = const_align;
1067 /* Reset the alignment in case we have made it tighter, so we can benefit
1068 from it in get_pointer_alignment. */
1069 SET_DECL_ALIGN (decl, align);
1072 /* Return DECL_ALIGN (decl), possibly increased for optimization purposes
1073 beyond what align_variable returned. */
1075 static unsigned int
1076 get_variable_align (tree decl)
1078 unsigned int align = DECL_ALIGN (decl);
1080 /* For user aligned vars or static vars align_variable already did
1081 everything. */
1082 if (DECL_USER_ALIGN (decl) || !TREE_PUBLIC (decl))
1083 return align;
1085 #ifdef DATA_ABI_ALIGNMENT
1086 if (DECL_THREAD_LOCAL_P (decl))
1087 align = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1088 #endif
1090 /* For decls that bind to the current definition, align_variable
1091 did also everything, except for not assuming ABI required alignment
1092 of TLS variables. For other vars, increase the alignment here
1093 as an optimization. */
1094 if (!decl_binds_to_current_def_p (decl))
1096 /* On some machines, it is good to increase alignment sometimes. */
1097 #ifdef DATA_ALIGNMENT
1098 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1099 /* Don't increase alignment too much for TLS variables - TLS space
1100 is too precious. */
1101 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1102 align = data_align;
1103 #endif
1104 if (DECL_INITIAL (decl) != 0
1105 /* In LTO we have no errors in program; error_mark_node is used
1106 to mark offlined constructors. */
1107 && (in_lto_p || DECL_INITIAL (decl) != error_mark_node))
1109 unsigned int const_align
1110 = targetm.constant_alignment (DECL_INITIAL (decl), align);
1111 /* Don't increase alignment too much for TLS variables - TLS space
1112 is too precious. */
1113 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1114 align = const_align;
1118 return align;
1121 /* Return the section into which the given VAR_DECL or CONST_DECL
1122 should be placed. PREFER_NOSWITCH_P is true if a noswitch
1123 section should be used wherever possible. */
1125 section *
1126 get_variable_section (tree decl, bool prefer_noswitch_p)
1128 addr_space_t as = ADDR_SPACE_GENERIC;
1129 int reloc;
1130 varpool_node *vnode = varpool_node::get (decl);
1131 if (vnode)
1133 vnode = vnode->ultimate_alias_target ();
1134 decl = vnode->decl;
1137 if (TREE_TYPE (decl) != error_mark_node)
1138 as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1140 /* We need the constructor to figure out reloc flag. */
1141 if (vnode)
1142 vnode->get_constructor ();
1144 if (DECL_COMMON (decl))
1146 /* If the decl has been given an explicit section name, or it resides
1147 in a non-generic address space, then it isn't common, and shouldn't
1148 be handled as such. */
1149 gcc_assert (DECL_SECTION_NAME (decl) == NULL
1150 && ADDR_SPACE_GENERIC_P (as));
1151 if (DECL_THREAD_LOCAL_P (decl))
1152 return tls_comm_section;
1153 else if (TREE_PUBLIC (decl) && bss_initializer_p (decl))
1154 return comm_section;
1157 if (DECL_INITIAL (decl) == error_mark_node)
1158 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1159 else if (DECL_INITIAL (decl))
1160 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1161 else
1162 reloc = 0;
1164 resolve_unique_section (decl, reloc, flag_data_sections);
1165 if (IN_NAMED_SECTION (decl))
1167 section *sect = get_named_section (decl, NULL, reloc);
1169 if ((sect->common.flags & SECTION_BSS) && !bss_initializer_p (decl))
1171 error_at (DECL_SOURCE_LOCATION (decl),
1172 "only zero initializers are allowed in section %qs",
1173 sect->named.name);
1174 DECL_INITIAL (decl) = error_mark_node;
1176 return sect;
1179 if (ADDR_SPACE_GENERIC_P (as)
1180 && !DECL_THREAD_LOCAL_P (decl)
1181 && !(prefer_noswitch_p && targetm.have_switchable_bss_sections)
1182 && bss_initializer_p (decl))
1184 if (!TREE_PUBLIC (decl)
1185 && !((flag_sanitize & SANITIZE_ADDRESS)
1186 && asan_protect_global (decl)))
1187 return lcomm_section;
1188 if (bss_noswitch_section)
1189 return bss_noswitch_section;
1192 return targetm.asm_out.select_section (decl, reloc,
1193 get_variable_align (decl));
1196 /* Return the block into which object_block DECL should be placed. */
1198 static struct object_block *
1199 get_block_for_decl (tree decl)
1201 section *sect;
1203 if (VAR_P (decl))
1205 /* The object must be defined in this translation unit. */
1206 if (DECL_EXTERNAL (decl))
1207 return NULL;
1209 /* There's no point using object blocks for something that is
1210 isolated by definition. */
1211 if (DECL_COMDAT_GROUP (decl))
1212 return NULL;
1215 /* We can only calculate block offsets if the decl has a known
1216 constant size. */
1217 if (DECL_SIZE_UNIT (decl) == NULL)
1218 return NULL;
1219 if (!tree_fits_uhwi_p (DECL_SIZE_UNIT (decl)))
1220 return NULL;
1222 /* Find out which section should contain DECL. We cannot put it into
1223 an object block if it requires a standalone definition. */
1224 if (VAR_P (decl))
1225 align_variable (decl, 0);
1226 sect = get_variable_section (decl, true);
1227 if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
1228 return NULL;
1230 return get_block_for_section (sect);
1233 /* Make sure block symbol SYMBOL is in block BLOCK. */
1235 static void
1236 change_symbol_block (rtx symbol, struct object_block *block)
1238 if (block != SYMBOL_REF_BLOCK (symbol))
1240 gcc_assert (SYMBOL_REF_BLOCK_OFFSET (symbol) < 0);
1241 SYMBOL_REF_BLOCK (symbol) = block;
1245 /* Return true if it is possible to put DECL in an object_block. */
1247 static bool
1248 use_blocks_for_decl_p (tree decl)
1250 struct symtab_node *snode;
1252 /* Only data DECLs can be placed into object blocks. */
1253 if (!VAR_P (decl) && TREE_CODE (decl) != CONST_DECL)
1254 return false;
1256 /* Detect decls created by dw2_force_const_mem. Such decls are
1257 special because DECL_INITIAL doesn't specify the decl's true value.
1258 dw2_output_indirect_constants will instead call assemble_variable
1259 with dont_output_data set to 1 and then print the contents itself. */
1260 if (DECL_INITIAL (decl) == decl)
1261 return false;
1263 /* If this decl is an alias, then we don't want to emit a
1264 definition. */
1265 if (VAR_P (decl)
1266 && (snode = symtab_node::get (decl)) != NULL
1267 && snode->alias)
1268 return false;
1270 return targetm.use_blocks_for_decl_p (decl);
1273 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS
1274 until we find an identifier that is not itself a transparent alias.
1275 Modify the alias passed to it by reference (and all aliases on the
1276 way to the ultimate target), such that they do not have to be
1277 followed again, and return the ultimate target of the alias
1278 chain. */
1280 static inline tree
1281 ultimate_transparent_alias_target (tree *alias)
1283 tree target = *alias;
1285 if (IDENTIFIER_TRANSPARENT_ALIAS (target))
1287 gcc_assert (TREE_CHAIN (target));
1288 target = ultimate_transparent_alias_target (&TREE_CHAIN (target));
1289 gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target)
1290 && ! TREE_CHAIN (target));
1291 *alias = target;
1294 return target;
1297 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
1298 have static storage duration. In other words, it should not be an
1299 automatic variable, including PARM_DECLs.
1301 There is, however, one exception: this function handles variables
1302 explicitly placed in a particular register by the user.
1304 This is never called for PARM_DECL nodes. */
1306 void
1307 make_decl_rtl (tree decl)
1309 const char *name = 0;
1310 int reg_number;
1311 tree id;
1312 rtx x;
1314 /* Check that we are not being given an automatic variable. */
1315 gcc_assert (TREE_CODE (decl) != PARM_DECL
1316 && TREE_CODE (decl) != RESULT_DECL);
1318 /* A weak alias has TREE_PUBLIC set but not the other bits. */
1319 gcc_assert (!VAR_P (decl)
1320 || TREE_STATIC (decl)
1321 || TREE_PUBLIC (decl)
1322 || DECL_EXTERNAL (decl)
1323 || DECL_REGISTER (decl));
1325 /* And that we were not given a type or a label. */
1326 gcc_assert (TREE_CODE (decl) != TYPE_DECL
1327 && TREE_CODE (decl) != LABEL_DECL);
1329 /* For a duplicate declaration, we can be called twice on the
1330 same DECL node. Don't discard the RTL already made. */
1331 if (DECL_RTL_SET_P (decl))
1333 /* If the old RTL had the wrong mode, fix the mode. */
1334 x = DECL_RTL (decl);
1335 if (GET_MODE (x) != DECL_MODE (decl))
1336 SET_DECL_RTL (decl, adjust_address_nv (x, DECL_MODE (decl), 0));
1338 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1339 return;
1341 /* ??? Another way to do this would be to maintain a hashed
1342 table of such critters. Instead of adding stuff to a DECL
1343 to give certain attributes to it, we could use an external
1344 hash map from DECL to set of attributes. */
1346 /* Let the target reassign the RTL if it wants.
1347 This is necessary, for example, when one machine specific
1348 decl attribute overrides another. */
1349 targetm.encode_section_info (decl, DECL_RTL (decl), false);
1351 /* If the symbol has a SYMBOL_REF_BLOCK field, update it based
1352 on the new decl information. */
1353 if (MEM_P (x)
1354 && GET_CODE (XEXP (x, 0)) == SYMBOL_REF
1355 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (x, 0)))
1356 change_symbol_block (XEXP (x, 0), get_block_for_decl (decl));
1358 return;
1361 /* If this variable belongs to the global constant pool, retrieve the
1362 pre-computed RTL or recompute it in LTO mode. */
1363 if (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
1365 SET_DECL_RTL (decl, output_constant_def (DECL_INITIAL (decl), 1));
1366 return;
1369 id = DECL_ASSEMBLER_NAME (decl);
1370 if (TREE_CODE (decl) == FUNCTION_DECL
1371 && cgraph_node::get (decl)
1372 && cgraph_node::get (decl)->instrumentation_clone)
1373 ultimate_transparent_alias_target (&id);
1374 name = IDENTIFIER_POINTER (id);
1376 if (name[0] != '*' && TREE_CODE (decl) != FUNCTION_DECL
1377 && DECL_REGISTER (decl))
1379 error ("register name not specified for %q+D", decl);
1381 else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1383 const char *asmspec = name+1;
1384 machine_mode mode = DECL_MODE (decl);
1385 reg_number = decode_reg_name (asmspec);
1386 /* First detect errors in declaring global registers. */
1387 if (reg_number == -1)
1388 error ("register name not specified for %q+D", decl);
1389 else if (reg_number < 0)
1390 error ("invalid register name for %q+D", decl);
1391 else if (mode == BLKmode)
1392 error ("data type of %q+D isn%'t suitable for a register",
1393 decl);
1394 else if (!in_hard_reg_set_p (accessible_reg_set, mode, reg_number))
1395 error ("the register specified for %q+D cannot be accessed"
1396 " by the current target", decl);
1397 else if (!in_hard_reg_set_p (operand_reg_set, mode, reg_number))
1398 error ("the register specified for %q+D is not general enough"
1399 " to be used as a register variable", decl);
1400 else if (!targetm.hard_regno_mode_ok (reg_number, mode))
1401 error ("register specified for %q+D isn%'t suitable for data type",
1402 decl);
1403 /* Now handle properly declared static register variables. */
1404 else
1406 int nregs;
1408 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
1410 DECL_INITIAL (decl) = 0;
1411 error ("global register variable has initial value");
1413 if (TREE_THIS_VOLATILE (decl))
1414 warning (OPT_Wvolatile_register_var,
1415 "optimization may eliminate reads and/or "
1416 "writes to register variables");
1418 /* If the user specified one of the eliminables registers here,
1419 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
1420 confused with that register and be eliminated. This usage is
1421 somewhat suspect... */
1423 SET_DECL_RTL (decl, gen_raw_REG (mode, reg_number));
1424 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
1425 REG_USERVAR_P (DECL_RTL (decl)) = 1;
1427 if (TREE_STATIC (decl))
1429 /* Make this register global, so not usable for anything
1430 else. */
1431 #ifdef ASM_DECLARE_REGISTER_GLOBAL
1432 name = IDENTIFIER_POINTER (DECL_NAME (decl));
1433 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
1434 #endif
1435 nregs = hard_regno_nregs (reg_number, mode);
1436 while (nregs > 0)
1437 globalize_reg (decl, reg_number + --nregs);
1440 /* As a register variable, it has no section. */
1441 return;
1443 /* Avoid internal errors from invalid register
1444 specifications. */
1445 SET_DECL_ASSEMBLER_NAME (decl, NULL_TREE);
1446 DECL_HARD_REGISTER (decl) = 0;
1447 /* Also avoid SSA inconsistencies by pretending this is an external
1448 decl now. */
1449 DECL_EXTERNAL (decl) = 1;
1450 return;
1452 /* Now handle ordinary static variables and functions (in memory).
1453 Also handle vars declared register invalidly. */
1454 else if (name[0] == '*')
1456 #ifdef REGISTER_PREFIX
1457 if (strlen (REGISTER_PREFIX) != 0)
1459 reg_number = decode_reg_name (name);
1460 if (reg_number >= 0 || reg_number == -3)
1461 error ("register name given for non-register variable %q+D", decl);
1463 #endif
1466 /* Specifying a section attribute on a variable forces it into a
1467 non-.bss section, and thus it cannot be common. */
1468 /* FIXME: In general this code should not be necessary because
1469 visibility pass is doing the same work. But notice_global_symbol
1470 is called early and it needs to make DECL_RTL to get the name.
1471 we take care of recomputing the DECL_RTL after visibility is changed. */
1472 if (VAR_P (decl)
1473 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl))
1474 && DECL_SECTION_NAME (decl) != NULL
1475 && DECL_INITIAL (decl) == NULL_TREE
1476 && DECL_COMMON (decl))
1477 DECL_COMMON (decl) = 0;
1479 /* Variables can't be both common and weak. */
1480 if (VAR_P (decl) && DECL_WEAK (decl))
1481 DECL_COMMON (decl) = 0;
1483 if (use_object_blocks_p () && use_blocks_for_decl_p (decl))
1484 x = create_block_symbol (name, get_block_for_decl (decl), -1);
1485 else
1487 machine_mode address_mode = Pmode;
1488 if (TREE_TYPE (decl) != error_mark_node)
1490 addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1491 address_mode = targetm.addr_space.address_mode (as);
1493 x = gen_rtx_SYMBOL_REF (address_mode, name);
1495 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
1496 SET_SYMBOL_REF_DECL (x, decl);
1498 x = gen_rtx_MEM (DECL_MODE (decl), x);
1499 if (TREE_CODE (decl) != FUNCTION_DECL)
1500 set_mem_attributes (x, decl, 1);
1501 SET_DECL_RTL (decl, x);
1503 /* Optionally set flags or add text to the name to record information
1504 such as that it is a function name.
1505 If the name is changed, the macro ASM_OUTPUT_LABELREF
1506 will have to know how to strip this information. */
1507 targetm.encode_section_info (decl, DECL_RTL (decl), true);
1510 /* Like make_decl_rtl, but inhibit creation of new alias sets when
1511 calling make_decl_rtl. Also, reset DECL_RTL before returning the
1512 rtl. */
1515 make_decl_rtl_for_debug (tree decl)
1517 unsigned int save_aliasing_flag;
1518 rtx rtl;
1520 if (DECL_RTL_SET_P (decl))
1521 return DECL_RTL (decl);
1523 /* Kludge alert! Somewhere down the call chain, make_decl_rtl will
1524 call new_alias_set. If running with -fcompare-debug, sometimes
1525 we do not want to create alias sets that will throw the alias
1526 numbers off in the comparison dumps. So... clearing
1527 flag_strict_aliasing will keep new_alias_set() from creating a
1528 new set. */
1529 save_aliasing_flag = flag_strict_aliasing;
1530 flag_strict_aliasing = 0;
1532 rtl = DECL_RTL (decl);
1533 /* Reset DECL_RTL back, as various parts of the compiler expects
1534 DECL_RTL set meaning it is actually going to be output. */
1535 SET_DECL_RTL (decl, NULL);
1537 flag_strict_aliasing = save_aliasing_flag;
1538 return rtl;
1541 /* Output a string of literal assembler code
1542 for an `asm' keyword used between functions. */
1544 void
1545 assemble_asm (tree string)
1547 const char *p;
1548 app_enable ();
1550 if (TREE_CODE (string) == ADDR_EXPR)
1551 string = TREE_OPERAND (string, 0);
1553 p = TREE_STRING_POINTER (string);
1554 fprintf (asm_out_file, "%s%s\n", p[0] == '\t' ? "" : "\t", p);
1557 /* Write the address of the entity given by SYMBOL to SEC. */
1558 void
1559 assemble_addr_to_section (rtx symbol, section *sec)
1561 switch_to_section (sec);
1562 assemble_align (POINTER_SIZE);
1563 assemble_integer (symbol, POINTER_SIZE_UNITS, POINTER_SIZE, 1);
1566 /* Return the numbered .ctors.N (if CONSTRUCTOR_P) or .dtors.N (if
1567 not) section for PRIORITY. */
1568 section *
1569 get_cdtor_priority_section (int priority, bool constructor_p)
1571 /* Buffer conservatively large enough for the full range of a 32-bit
1572 int plus the text below. */
1573 char buf[18];
1575 /* ??? This only works reliably with the GNU linker. */
1576 sprintf (buf, "%s.%.5u",
1577 constructor_p ? ".ctors" : ".dtors",
1578 /* Invert the numbering so the linker puts us in the proper
1579 order; constructors are run from right to left, and the
1580 linker sorts in increasing order. */
1581 MAX_INIT_PRIORITY - priority);
1582 return get_section (buf, SECTION_WRITE, NULL);
1585 void
1586 default_named_section_asm_out_destructor (rtx symbol, int priority)
1588 section *sec;
1590 if (priority != DEFAULT_INIT_PRIORITY)
1591 sec = get_cdtor_priority_section (priority,
1592 /*constructor_p=*/false);
1593 else
1594 sec = get_section (".dtors", SECTION_WRITE, NULL);
1596 assemble_addr_to_section (symbol, sec);
1599 #ifdef DTORS_SECTION_ASM_OP
1600 void
1601 default_dtor_section_asm_out_destructor (rtx symbol,
1602 int priority ATTRIBUTE_UNUSED)
1604 assemble_addr_to_section (symbol, dtors_section);
1606 #endif
1608 void
1609 default_named_section_asm_out_constructor (rtx symbol, int priority)
1611 section *sec;
1613 if (priority != DEFAULT_INIT_PRIORITY)
1614 sec = get_cdtor_priority_section (priority,
1615 /*constructor_p=*/true);
1616 else
1617 sec = get_section (".ctors", SECTION_WRITE, NULL);
1619 assemble_addr_to_section (symbol, sec);
1622 #ifdef CTORS_SECTION_ASM_OP
1623 void
1624 default_ctor_section_asm_out_constructor (rtx symbol,
1625 int priority ATTRIBUTE_UNUSED)
1627 assemble_addr_to_section (symbol, ctors_section);
1629 #endif
1631 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1632 a nonzero value if the constant pool should be output before the
1633 start of the function, or a zero value if the pool should output
1634 after the end of the function. The default is to put it before the
1635 start. */
1637 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1638 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1639 #endif
1641 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1642 to be output to assembler.
1643 Set first_global_object_name and weak_global_object_name as appropriate. */
1645 void
1646 notice_global_symbol (tree decl)
1648 const char **t = &first_global_object_name;
1650 if (first_global_object_name
1651 || !TREE_PUBLIC (decl)
1652 || DECL_EXTERNAL (decl)
1653 || !DECL_NAME (decl)
1654 || (VAR_P (decl) && DECL_HARD_REGISTER (decl))
1655 || (TREE_CODE (decl) != FUNCTION_DECL
1656 && (!VAR_P (decl)
1657 || (DECL_COMMON (decl)
1658 && (DECL_INITIAL (decl) == 0
1659 || DECL_INITIAL (decl) == error_mark_node)))))
1660 return;
1662 /* We win when global object is found, but it is useful to know about weak
1663 symbol as well so we can produce nicer unique names. */
1664 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl) || flag_shlib)
1665 t = &weak_global_object_name;
1667 if (!*t)
1669 tree id = DECL_ASSEMBLER_NAME (decl);
1670 ultimate_transparent_alias_target (&id);
1671 *t = ggc_strdup (targetm.strip_name_encoding (IDENTIFIER_POINTER (id)));
1675 /* If not using flag_reorder_blocks_and_partition, decide early whether the
1676 current function goes into the cold section, so that targets can use
1677 current_function_section during RTL expansion. DECL describes the
1678 function. */
1680 void
1681 decide_function_section (tree decl)
1683 first_function_block_is_cold = false;
1685 if (DECL_SECTION_NAME (decl))
1687 struct cgraph_node *node = cgraph_node::get (current_function_decl);
1688 /* Calls to function_section rely on first_function_block_is_cold
1689 being accurate. */
1690 first_function_block_is_cold = (node
1691 && node->frequency
1692 == NODE_FREQUENCY_UNLIKELY_EXECUTED);
1695 in_cold_section_p = first_function_block_is_cold;
1698 /* Get the function's name, as described by its RTL. This may be
1699 different from the DECL_NAME name used in the source file. */
1700 const char *
1701 get_fnname_from_decl (tree decl)
1703 rtx x = DECL_RTL (decl);
1704 gcc_assert (MEM_P (x));
1705 x = XEXP (x, 0);
1706 gcc_assert (GET_CODE (x) == SYMBOL_REF);
1707 return XSTR (x, 0);
1710 /* Output assembler code for the constant pool of a function and associated
1711 with defining the name of the function. DECL describes the function.
1712 NAME is the function's name. For the constant pool, we use the current
1713 constant pool data. */
1715 void
1716 assemble_start_function (tree decl, const char *fnname)
1718 int align;
1719 char tmp_label[100];
1720 bool hot_label_written = false;
1722 if (crtl->has_bb_partition)
1724 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTB", const_labelno);
1725 crtl->subsections.hot_section_label = ggc_strdup (tmp_label);
1726 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDB", const_labelno);
1727 crtl->subsections.cold_section_label = ggc_strdup (tmp_label);
1728 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTE", const_labelno);
1729 crtl->subsections.hot_section_end_label = ggc_strdup (tmp_label);
1730 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDE", const_labelno);
1731 crtl->subsections.cold_section_end_label = ggc_strdup (tmp_label);
1732 const_labelno++;
1733 cold_function_name = NULL_TREE;
1735 else
1737 crtl->subsections.hot_section_label = NULL;
1738 crtl->subsections.cold_section_label = NULL;
1739 crtl->subsections.hot_section_end_label = NULL;
1740 crtl->subsections.cold_section_end_label = NULL;
1743 /* The following code does not need preprocessing in the assembler. */
1745 app_disable ();
1747 if (CONSTANT_POOL_BEFORE_FUNCTION)
1748 output_constant_pool (fnname, decl);
1750 align = symtab_node::get (decl)->definition_alignment ();
1752 /* Make sure the not and cold text (code) sections are properly
1753 aligned. This is necessary here in the case where the function
1754 has both hot and cold sections, because we don't want to re-set
1755 the alignment when the section switch happens mid-function. */
1757 if (crtl->has_bb_partition)
1759 first_function_block_is_cold = false;
1761 switch_to_section (unlikely_text_section ());
1762 assemble_align (align);
1763 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_label);
1765 /* When the function starts with a cold section, we need to explicitly
1766 align the hot section and write out the hot section label.
1767 But if the current function is a thunk, we do not have a CFG. */
1768 if (!cfun->is_thunk
1769 && BB_PARTITION (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) == BB_COLD_PARTITION)
1771 switch_to_section (text_section);
1772 assemble_align (align);
1773 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1774 hot_label_written = true;
1775 first_function_block_is_cold = true;
1777 in_cold_section_p = first_function_block_is_cold;
1781 /* Switch to the correct text section for the start of the function. */
1783 switch_to_section (function_section (decl));
1784 if (crtl->has_bb_partition && !hot_label_written)
1785 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1787 /* Tell assembler to move to target machine's alignment for functions. */
1788 align = floor_log2 (align / BITS_PER_UNIT);
1789 if (align > 0)
1791 ASM_OUTPUT_ALIGN (asm_out_file, align);
1794 /* Handle a user-specified function alignment.
1795 Note that we still need to align to DECL_ALIGN, as above,
1796 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1797 if (! DECL_USER_ALIGN (decl)
1798 && align_functions_log > align
1799 && optimize_function_for_speed_p (cfun))
1801 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1802 int align_log = align_functions_log;
1803 #endif
1804 int max_skip = align_functions - 1;
1805 if (flag_limit_function_alignment && crtl->max_insn_address > 0
1806 && max_skip >= crtl->max_insn_address)
1807 max_skip = crtl->max_insn_address - 1;
1809 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1810 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file, align_log, max_skip);
1811 #else
1812 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1813 #endif
1816 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1817 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1818 #endif
1820 if (!DECL_IGNORED_P (decl))
1821 (*debug_hooks->begin_function) (decl);
1823 /* Make function name accessible from other files, if appropriate. */
1825 if (TREE_PUBLIC (decl)
1826 || (cgraph_node::get (decl)->instrumentation_clone
1827 && cgraph_node::get (decl)->instrumented_version
1828 && TREE_PUBLIC (cgraph_node::get (decl)->instrumented_version->decl)))
1830 notice_global_symbol (decl);
1832 globalize_decl (decl);
1834 maybe_assemble_visibility (decl);
1837 if (DECL_PRESERVE_P (decl))
1838 targetm.asm_out.mark_decl_preserved (fnname);
1840 unsigned HOST_WIDE_INT patch_area_size = function_entry_patch_area_size;
1841 unsigned HOST_WIDE_INT patch_area_entry = function_entry_patch_area_start;
1843 tree patchable_function_entry_attr
1844 = lookup_attribute ("patchable_function_entry", DECL_ATTRIBUTES (decl));
1845 if (patchable_function_entry_attr)
1847 tree pp_val = TREE_VALUE (patchable_function_entry_attr);
1848 tree patchable_function_entry_value1 = TREE_VALUE (pp_val);
1850 if (tree_fits_uhwi_p (patchable_function_entry_value1))
1851 patch_area_size = tree_to_uhwi (patchable_function_entry_value1);
1852 else
1853 gcc_unreachable ();
1855 patch_area_entry = 0;
1856 if (list_length (pp_val) > 1)
1858 tree patchable_function_entry_value2 =
1859 TREE_VALUE (TREE_CHAIN (pp_val));
1861 if (tree_fits_uhwi_p (patchable_function_entry_value2))
1862 patch_area_entry = tree_to_uhwi (patchable_function_entry_value2);
1863 else
1864 gcc_unreachable ();
1868 if (patch_area_entry > patch_area_size)
1870 if (patch_area_size > 0)
1871 warning (OPT_Wattributes, "Patchable function entry > size");
1872 patch_area_entry = 0;
1875 /* Emit the patching area before the entry label, if any. */
1876 if (patch_area_entry > 0)
1877 targetm.asm_out.print_patchable_function_entry (asm_out_file,
1878 patch_area_entry, true);
1880 /* Do any machine/system dependent processing of the function name. */
1881 #ifdef ASM_DECLARE_FUNCTION_NAME
1882 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1883 #else
1884 /* Standard thing is just output label for the function. */
1885 ASM_OUTPUT_FUNCTION_LABEL (asm_out_file, fnname, current_function_decl);
1886 #endif /* ASM_DECLARE_FUNCTION_NAME */
1888 /* And the area after the label. Record it if we haven't done so yet. */
1889 if (patch_area_size > patch_area_entry)
1890 targetm.asm_out.print_patchable_function_entry (asm_out_file,
1891 patch_area_size-patch_area_entry,
1892 patch_area_entry == 0);
1894 if (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (decl)))
1895 saw_no_split_stack = true;
1898 /* Output assembler code associated with defining the size of the
1899 function. DECL describes the function. NAME is the function's name. */
1901 void
1902 assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED)
1904 #ifdef ASM_DECLARE_FUNCTION_SIZE
1905 /* We could have switched section in the middle of the function. */
1906 if (crtl->has_bb_partition)
1907 switch_to_section (function_section (decl));
1908 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1909 #endif
1910 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1912 output_constant_pool (fnname, decl);
1913 switch_to_section (function_section (decl)); /* need to switch back */
1915 /* Output labels for end of hot/cold text sections (to be used by
1916 debug info.) */
1917 if (crtl->has_bb_partition)
1919 section *save_text_section;
1921 save_text_section = in_section;
1922 switch_to_section (unlikely_text_section ());
1923 #ifdef ASM_DECLARE_COLD_FUNCTION_SIZE
1924 if (cold_function_name != NULL_TREE)
1925 ASM_DECLARE_COLD_FUNCTION_SIZE (asm_out_file,
1926 IDENTIFIER_POINTER (cold_function_name),
1927 decl);
1928 #endif
1929 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label);
1930 if (first_function_block_is_cold)
1931 switch_to_section (text_section);
1932 else
1933 switch_to_section (function_section (decl));
1934 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label);
1935 switch_to_section (save_text_section);
1939 /* Assemble code to leave SIZE bytes of zeros. */
1941 void
1942 assemble_zeros (unsigned HOST_WIDE_INT size)
1944 /* Do no output if -fsyntax-only. */
1945 if (flag_syntax_only)
1946 return;
1948 #ifdef ASM_NO_SKIP_IN_TEXT
1949 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1950 so we must output 0s explicitly in the text section. */
1951 if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0)
1953 unsigned HOST_WIDE_INT i;
1954 for (i = 0; i < size; i++)
1955 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1957 else
1958 #endif
1959 if (size > 0)
1960 ASM_OUTPUT_SKIP (asm_out_file, size);
1963 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1965 void
1966 assemble_align (int align)
1968 if (align > BITS_PER_UNIT)
1970 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1974 /* Assemble a string constant with the specified C string as contents. */
1976 void
1977 assemble_string (const char *p, int size)
1979 int pos = 0;
1980 int maximum = 2000;
1982 /* If the string is very long, split it up. */
1984 while (pos < size)
1986 int thissize = size - pos;
1987 if (thissize > maximum)
1988 thissize = maximum;
1990 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1992 pos += thissize;
1993 p += thissize;
1998 /* A noswitch_section_callback for lcomm_section. */
2000 static bool
2001 emit_local (tree decl ATTRIBUTE_UNUSED,
2002 const char *name ATTRIBUTE_UNUSED,
2003 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2004 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2006 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
2007 unsigned int align = symtab_node::get (decl)->definition_alignment ();
2008 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name,
2009 size, align);
2010 return true;
2011 #elif defined ASM_OUTPUT_ALIGNED_LOCAL
2012 unsigned int align = symtab_node::get (decl)->definition_alignment ();
2013 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, align);
2014 return true;
2015 #else
2016 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2017 return false;
2018 #endif
2021 /* A noswitch_section_callback for bss_noswitch_section. */
2023 #if defined ASM_OUTPUT_ALIGNED_BSS
2024 static bool
2025 emit_bss (tree decl ATTRIBUTE_UNUSED,
2026 const char *name ATTRIBUTE_UNUSED,
2027 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2028 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2030 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size,
2031 get_variable_align (decl));
2032 return true;
2034 #endif
2036 /* A noswitch_section_callback for comm_section. */
2038 static bool
2039 emit_common (tree decl ATTRIBUTE_UNUSED,
2040 const char *name ATTRIBUTE_UNUSED,
2041 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2042 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2044 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
2045 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name,
2046 size, get_variable_align (decl));
2047 return true;
2048 #elif defined ASM_OUTPUT_ALIGNED_COMMON
2049 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size,
2050 get_variable_align (decl));
2051 return true;
2052 #else
2053 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
2054 return false;
2055 #endif
2058 /* A noswitch_section_callback for tls_comm_section. */
2060 static bool
2061 emit_tls_common (tree decl ATTRIBUTE_UNUSED,
2062 const char *name ATTRIBUTE_UNUSED,
2063 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2064 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2066 #ifdef ASM_OUTPUT_TLS_COMMON
2067 ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size);
2068 return true;
2069 #else
2070 sorry ("thread-local COMMON data not implemented");
2071 return true;
2072 #endif
2075 /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT.
2076 NAME is the name of DECL's SYMBOL_REF. */
2078 static void
2079 assemble_noswitch_variable (tree decl, const char *name, section *sect,
2080 unsigned int align)
2082 unsigned HOST_WIDE_INT size, rounded;
2084 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2085 rounded = size;
2087 if ((flag_sanitize & SANITIZE_ADDRESS) && asan_protect_global (decl))
2088 size += asan_red_zone_size (size);
2090 /* Don't allocate zero bytes of common,
2091 since that means "undefined external" in the linker. */
2092 if (size == 0)
2093 rounded = 1;
2095 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2096 so that each uninitialized object starts on such a boundary. */
2097 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
2098 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2099 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2101 if (!sect->noswitch.callback (decl, name, size, rounded)
2102 && (unsigned HOST_WIDE_INT) (align / BITS_PER_UNIT) > rounded)
2103 error ("requested alignment for %q+D is greater than "
2104 "implemented alignment of %wu", decl, rounded);
2107 /* A subroutine of assemble_variable. Output the label and contents of
2108 DECL, whose address is a SYMBOL_REF with name NAME. DONT_OUTPUT_DATA
2109 is as for assemble_variable. */
2111 static void
2112 assemble_variable_contents (tree decl, const char *name,
2113 bool dont_output_data)
2115 /* Do any machine/system dependent processing of the object. */
2116 #ifdef ASM_DECLARE_OBJECT_NAME
2117 last_assemble_variable_decl = decl;
2118 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
2119 #else
2120 /* Standard thing is just output label for the object. */
2121 ASM_OUTPUT_LABEL (asm_out_file, name);
2122 #endif /* ASM_DECLARE_OBJECT_NAME */
2124 if (!dont_output_data)
2126 /* Caller is supposed to use varpool_get_constructor when it wants
2127 to output the body. */
2128 gcc_assert (!in_lto_p || DECL_INITIAL (decl) != error_mark_node);
2129 if (DECL_INITIAL (decl)
2130 && DECL_INITIAL (decl) != error_mark_node
2131 && !initializer_zerop (DECL_INITIAL (decl)))
2132 /* Output the actual data. */
2133 output_constant (DECL_INITIAL (decl),
2134 tree_to_uhwi (DECL_SIZE_UNIT (decl)),
2135 get_variable_align (decl),
2136 false);
2137 else
2138 /* Leave space for it. */
2139 assemble_zeros (tree_to_uhwi (DECL_SIZE_UNIT (decl)));
2140 targetm.asm_out.decl_end ();
2144 /* Write out assembly for the variable DECL, which is not defined in
2145 the current translation unit. */
2146 void
2147 assemble_undefined_decl (tree decl)
2149 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
2150 targetm.asm_out.assemble_undefined_decl (asm_out_file, name, decl);
2153 /* Assemble everything that is needed for a variable or function declaration.
2154 Not used for automatic variables, and not used for function definitions.
2155 Should not be called for variables of incomplete structure type.
2157 TOP_LEVEL is nonzero if this variable has file scope.
2158 AT_END is nonzero if this is the special handling, at end of compilation,
2159 to define things that have had only tentative definitions.
2160 DONT_OUTPUT_DATA if nonzero means don't actually output the
2161 initial value (that will be done by the caller). */
2163 void
2164 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
2165 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
2167 const char *name;
2168 rtx decl_rtl, symbol;
2169 section *sect;
2170 unsigned int align;
2171 bool asan_protected = false;
2173 /* This function is supposed to handle VARIABLES. Ensure we have one. */
2174 gcc_assert (VAR_P (decl));
2176 /* Emulated TLS had better not get this far. */
2177 gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl));
2179 last_assemble_variable_decl = 0;
2181 /* Normally no need to say anything here for external references,
2182 since assemble_external is called by the language-specific code
2183 when a declaration is first seen. */
2185 if (DECL_EXTERNAL (decl))
2186 return;
2188 /* Do nothing for global register variables. */
2189 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
2191 TREE_ASM_WRITTEN (decl) = 1;
2192 return;
2195 /* If type was incomplete when the variable was declared,
2196 see if it is complete now. */
2198 if (DECL_SIZE (decl) == 0)
2199 layout_decl (decl, 0);
2201 /* Still incomplete => don't allocate it; treat the tentative defn
2202 (which is what it must have been) as an `extern' reference. */
2204 if (!dont_output_data && DECL_SIZE (decl) == 0)
2206 error ("storage size of %q+D isn%'t known", decl);
2207 TREE_ASM_WRITTEN (decl) = 1;
2208 return;
2211 /* The first declaration of a variable that comes through this function
2212 decides whether it is global (in C, has external linkage)
2213 or local (in C, has internal linkage). So do nothing more
2214 if this function has already run. */
2216 if (TREE_ASM_WRITTEN (decl))
2217 return;
2219 /* Make sure targetm.encode_section_info is invoked before we set
2220 ASM_WRITTEN. */
2221 decl_rtl = DECL_RTL (decl);
2223 TREE_ASM_WRITTEN (decl) = 1;
2225 /* Do no output if -fsyntax-only. */
2226 if (flag_syntax_only)
2227 return;
2229 if (! dont_output_data
2230 && ! valid_constant_size_p (DECL_SIZE_UNIT (decl)))
2232 error ("size of variable %q+D is too large", decl);
2233 return;
2236 gcc_assert (MEM_P (decl_rtl));
2237 gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF);
2238 symbol = XEXP (decl_rtl, 0);
2240 /* If this symbol belongs to the tree constant pool, output the constant
2241 if it hasn't already been written. */
2242 if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
2244 tree decl = SYMBOL_REF_DECL (symbol);
2245 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
2246 output_constant_def_contents (symbol);
2247 return;
2250 app_disable ();
2252 name = XSTR (symbol, 0);
2253 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
2254 notice_global_symbol (decl);
2256 /* Compute the alignment of this data. */
2258 align_variable (decl, dont_output_data);
2260 if ((flag_sanitize & SANITIZE_ADDRESS)
2261 && asan_protect_global (decl))
2263 asan_protected = true;
2264 SET_DECL_ALIGN (decl, MAX (DECL_ALIGN (decl),
2265 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT));
2268 set_mem_align (decl_rtl, DECL_ALIGN (decl));
2270 align = get_variable_align (decl);
2272 if (TREE_PUBLIC (decl))
2273 maybe_assemble_visibility (decl);
2275 if (DECL_PRESERVE_P (decl))
2276 targetm.asm_out.mark_decl_preserved (name);
2278 /* First make the assembler name(s) global if appropriate. */
2279 sect = get_variable_section (decl, false);
2280 if (TREE_PUBLIC (decl)
2281 && (sect->common.flags & SECTION_COMMON) == 0)
2282 globalize_decl (decl);
2284 /* Output any data that we will need to use the address of. */
2285 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
2286 output_addressed_constants (DECL_INITIAL (decl));
2288 /* dbxout.c needs to know this. */
2289 if (sect && (sect->common.flags & SECTION_CODE) != 0)
2290 DECL_IN_TEXT_SECTION (decl) = 1;
2292 /* If the decl is part of an object_block, make sure that the decl
2293 has been positioned within its block, but do not write out its
2294 definition yet. output_object_blocks will do that later. */
2295 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
2297 gcc_assert (!dont_output_data);
2298 place_block_symbol (symbol);
2300 else if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
2301 assemble_noswitch_variable (decl, name, sect, align);
2302 else
2304 /* Special-case handling of vtv comdat sections. */
2305 if (sect->named.name
2306 && (strcmp (sect->named.name, ".vtable_map_vars") == 0))
2307 handle_vtv_comdat_section (sect, decl);
2308 else
2309 switch_to_section (sect);
2310 if (align > BITS_PER_UNIT)
2311 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2312 assemble_variable_contents (decl, name, dont_output_data);
2313 if (asan_protected)
2315 unsigned HOST_WIDE_INT int size
2316 = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2317 assemble_zeros (asan_red_zone_size (size));
2323 /* Given a function declaration (FN_DECL), this function assembles the
2324 function into the .preinit_array section. */
2326 void
2327 assemble_vtv_preinit_initializer (tree fn_decl)
2329 section *sect;
2330 unsigned flags = SECTION_WRITE;
2331 rtx symbol = XEXP (DECL_RTL (fn_decl), 0);
2333 flags |= SECTION_NOTYPE;
2334 sect = get_section (".preinit_array", flags, fn_decl);
2335 switch_to_section (sect);
2336 assemble_addr_to_section (symbol, sect);
2339 /* Return 1 if type TYPE contains any pointers. */
2341 static int
2342 contains_pointers_p (tree type)
2344 switch (TREE_CODE (type))
2346 case POINTER_TYPE:
2347 case REFERENCE_TYPE:
2348 /* I'm not sure whether OFFSET_TYPE needs this treatment,
2349 so I'll play safe and return 1. */
2350 case OFFSET_TYPE:
2351 return 1;
2353 case RECORD_TYPE:
2354 case UNION_TYPE:
2355 case QUAL_UNION_TYPE:
2357 tree fields;
2358 /* For a type that has fields, see if the fields have pointers. */
2359 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2360 if (TREE_CODE (fields) == FIELD_DECL
2361 && contains_pointers_p (TREE_TYPE (fields)))
2362 return 1;
2363 return 0;
2366 case ARRAY_TYPE:
2367 /* An array type contains pointers if its element type does. */
2368 return contains_pointers_p (TREE_TYPE (type));
2370 default:
2371 return 0;
2375 /* We delay assemble_external processing until
2376 the compilation unit is finalized. This is the best we can do for
2377 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2378 it all the way to final. See PR 17982 for further discussion. */
2379 static GTY(()) tree pending_assemble_externals;
2381 #ifdef ASM_OUTPUT_EXTERNAL
2382 /* Some targets delay some output to final using TARGET_ASM_FILE_END.
2383 As a result, assemble_external can be called after the list of externals
2384 is processed and the pointer set destroyed. */
2385 static bool pending_assemble_externals_processed;
2387 /* Avoid O(external_decls**2) lookups in the pending_assemble_externals
2388 TREE_LIST in assemble_external. */
2389 static hash_set<tree> *pending_assemble_externals_set;
2391 /* True if DECL is a function decl for which no out-of-line copy exists.
2392 It is assumed that DECL's assembler name has been set. */
2394 static bool
2395 incorporeal_function_p (tree decl)
2397 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
2399 const char *name;
2401 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2402 && ALLOCA_FUNCTION_CODE_P (DECL_FUNCTION_CODE (decl)))
2403 return true;
2405 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2406 /* Atomic or sync builtins which have survived this far will be
2407 resolved externally and therefore are not incorporeal. */
2408 if (strncmp (name, "__builtin_", 10) == 0)
2409 return true;
2411 return false;
2414 /* Actually do the tests to determine if this is necessary, and invoke
2415 ASM_OUTPUT_EXTERNAL. */
2416 static void
2417 assemble_external_real (tree decl)
2419 rtx rtl = DECL_RTL (decl);
2421 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2422 && !SYMBOL_REF_USED (XEXP (rtl, 0))
2423 && !incorporeal_function_p (decl))
2425 /* Some systems do require some output. */
2426 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2427 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2430 #endif
2432 void
2433 process_pending_assemble_externals (void)
2435 #ifdef ASM_OUTPUT_EXTERNAL
2436 tree list;
2437 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2438 assemble_external_real (TREE_VALUE (list));
2440 pending_assemble_externals = 0;
2441 pending_assemble_externals_processed = true;
2442 delete pending_assemble_externals_set;
2443 #endif
2446 /* This TREE_LIST contains any weak symbol declarations waiting
2447 to be emitted. */
2448 static GTY(()) tree weak_decls;
2450 /* Output something to declare an external symbol to the assembler,
2451 and qualifiers such as weakness. (Most assemblers don't need
2452 extern declaration, so we normally output nothing.) Do nothing if
2453 DECL is not external. */
2455 void
2456 assemble_external (tree decl ATTRIBUTE_UNUSED)
2458 /* Make sure that the ASM_OUT_FILE is open.
2459 If it's not, we should not be calling this function. */
2460 gcc_assert (asm_out_file);
2462 /* In a perfect world, the following condition would be true.
2463 Sadly, the Go front end emit assembly *from the front end*,
2464 bypassing the call graph. See PR52739. Fix before GCC 4.8. */
2465 #if 0
2466 /* This function should only be called if we are expanding, or have
2467 expanded, to RTL.
2468 Ideally, only final.c would be calling this function, but it is
2469 not clear whether that would break things somehow. See PR 17982
2470 for further discussion. */
2471 gcc_assert (state == EXPANSION
2472 || state == FINISHED);
2473 #endif
2475 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2476 return;
2478 /* We want to output annotation for weak and external symbols at
2479 very last to check if they are references or not. */
2481 if (TARGET_SUPPORTS_WEAK
2482 && DECL_WEAK (decl)
2483 /* TREE_STATIC is a weird and abused creature which is not
2484 generally the right test for whether an entity has been
2485 locally emitted, inlined or otherwise not-really-extern, but
2486 for declarations that can be weak, it happens to be
2487 match. */
2488 && !TREE_STATIC (decl)
2489 && lookup_attribute ("weak", DECL_ATTRIBUTES (decl))
2490 && value_member (decl, weak_decls) == NULL_TREE)
2491 weak_decls = tree_cons (NULL, decl, weak_decls);
2493 #ifdef ASM_OUTPUT_EXTERNAL
2494 if (pending_assemble_externals_processed)
2496 assemble_external_real (decl);
2497 return;
2500 if (! pending_assemble_externals_set->add (decl))
2501 pending_assemble_externals = tree_cons (NULL, decl,
2502 pending_assemble_externals);
2503 #endif
2506 /* Similar, for calling a library function FUN. */
2508 void
2509 assemble_external_libcall (rtx fun)
2511 /* Declare library function name external when first used, if nec. */
2512 if (! SYMBOL_REF_USED (fun))
2514 SYMBOL_REF_USED (fun) = 1;
2515 targetm.asm_out.external_libcall (fun);
2519 /* Assemble a label named NAME. */
2521 void
2522 assemble_label (FILE *file, const char *name)
2524 ASM_OUTPUT_LABEL (file, name);
2527 /* Set the symbol_referenced flag for ID. */
2528 void
2529 mark_referenced (tree id)
2531 TREE_SYMBOL_REFERENCED (id) = 1;
2534 /* Set the symbol_referenced flag for DECL and notify callgraph. */
2535 void
2536 mark_decl_referenced (tree decl)
2538 if (TREE_CODE (decl) == FUNCTION_DECL)
2540 /* Extern inline functions don't become needed when referenced.
2541 If we know a method will be emitted in other TU and no new
2542 functions can be marked reachable, just use the external
2543 definition. */
2544 struct cgraph_node *node = cgraph_node::get_create (decl);
2545 if (!DECL_EXTERNAL (decl)
2546 && !node->definition)
2547 node->mark_force_output ();
2549 else if (VAR_P (decl))
2551 varpool_node *node = varpool_node::get_create (decl);
2552 /* C++ frontend use mark_decl_references to force COMDAT variables
2553 to be output that might appear dead otherwise. */
2554 node->force_output = true;
2556 /* else do nothing - we can get various sorts of CST nodes here,
2557 which do not need to be marked. */
2561 /* Output to FILE (an assembly file) a reference to NAME. If NAME
2562 starts with a *, the rest of NAME is output verbatim. Otherwise
2563 NAME is transformed in a target-specific way (usually by the
2564 addition of an underscore). */
2566 void
2567 assemble_name_raw (FILE *file, const char *name)
2569 if (name[0] == '*')
2570 fputs (&name[1], file);
2571 else
2572 ASM_OUTPUT_LABELREF (file, name);
2575 /* Like assemble_name_raw, but should be used when NAME might refer to
2576 an entity that is also represented as a tree (like a function or
2577 variable). If NAME does refer to such an entity, that entity will
2578 be marked as referenced. */
2580 void
2581 assemble_name (FILE *file, const char *name)
2583 const char *real_name;
2584 tree id;
2586 real_name = targetm.strip_name_encoding (name);
2588 id = maybe_get_identifier (real_name);
2589 if (id)
2591 tree id_orig = id;
2593 mark_referenced (id);
2594 ultimate_transparent_alias_target (&id);
2595 if (id != id_orig)
2596 name = IDENTIFIER_POINTER (id);
2597 gcc_assert (! TREE_CHAIN (id));
2600 assemble_name_raw (file, name);
2603 /* Allocate SIZE bytes writable static space with a gensym name
2604 and return an RTX to refer to its address. */
2607 assemble_static_space (unsigned HOST_WIDE_INT size)
2609 char name[17];
2610 const char *namestring;
2611 rtx x;
2613 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2614 ++const_labelno;
2615 namestring = ggc_strdup (name);
2617 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2618 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2620 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2621 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2622 BIGGEST_ALIGNMENT);
2623 #else
2624 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2625 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2626 #else
2628 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2629 so that each uninitialized object starts on such a boundary. */
2630 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2631 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2632 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2633 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2634 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2635 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2637 #endif
2638 #endif
2639 return x;
2642 /* Assemble the static constant template for function entry trampolines.
2643 This is done at most once per compilation.
2644 Returns an RTX for the address of the template. */
2646 static GTY(()) rtx initial_trampoline;
2649 assemble_trampoline_template (void)
2651 char label[256];
2652 const char *name;
2653 int align;
2654 rtx symbol;
2656 gcc_assert (targetm.asm_out.trampoline_template != NULL);
2658 if (initial_trampoline)
2659 return initial_trampoline;
2661 /* By default, put trampoline templates in read-only data section. */
2663 #ifdef TRAMPOLINE_SECTION
2664 switch_to_section (TRAMPOLINE_SECTION);
2665 #else
2666 switch_to_section (readonly_data_section);
2667 #endif
2669 /* Write the assembler code to define one. */
2670 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2671 if (align > 0)
2672 ASM_OUTPUT_ALIGN (asm_out_file, align);
2674 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2675 targetm.asm_out.trampoline_template (asm_out_file);
2677 /* Record the rtl to refer to it. */
2678 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2679 name = ggc_strdup (label);
2680 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2681 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2683 initial_trampoline = gen_const_mem (BLKmode, symbol);
2684 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2685 set_mem_size (initial_trampoline, TRAMPOLINE_SIZE);
2687 return initial_trampoline;
2690 /* A and B are either alignments or offsets. Return the minimum alignment
2691 that may be assumed after adding the two together. */
2693 static inline unsigned
2694 min_align (unsigned int a, unsigned int b)
2696 return least_bit_hwi (a | b);
2699 /* Return the assembler directive for creating a given kind of integer
2700 object. SIZE is the number of bytes in the object and ALIGNED_P
2701 indicates whether it is known to be aligned. Return NULL if the
2702 assembly dialect has no such directive.
2704 The returned string should be printed at the start of a new line and
2705 be followed immediately by the object's initial value. */
2707 const char *
2708 integer_asm_op (int size, int aligned_p)
2710 struct asm_int_op *ops;
2712 if (aligned_p)
2713 ops = &targetm.asm_out.aligned_op;
2714 else
2715 ops = &targetm.asm_out.unaligned_op;
2717 switch (size)
2719 case 1:
2720 return targetm.asm_out.byte_op;
2721 case 2:
2722 return ops->hi;
2723 case 4:
2724 return ops->si;
2725 case 8:
2726 return ops->di;
2727 case 16:
2728 return ops->ti;
2729 default:
2730 return NULL;
2734 /* Use directive OP to assemble an integer object X. Print OP at the
2735 start of the line, followed immediately by the value of X. */
2737 void
2738 assemble_integer_with_op (const char *op, rtx x)
2740 fputs (op, asm_out_file);
2741 output_addr_const (asm_out_file, x);
2742 fputc ('\n', asm_out_file);
2745 /* The default implementation of the asm_out.integer target hook. */
2747 bool
2748 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2749 unsigned int size ATTRIBUTE_UNUSED,
2750 int aligned_p ATTRIBUTE_UNUSED)
2752 const char *op = integer_asm_op (size, aligned_p);
2753 /* Avoid GAS bugs for large values. Specifically negative values whose
2754 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2755 if (size > UNITS_PER_WORD && size > POINTER_SIZE_UNITS)
2756 return false;
2757 return op && (assemble_integer_with_op (op, x), true);
2760 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2761 the alignment of the integer in bits. Return 1 if we were able to output
2762 the constant, otherwise 0. We must be able to output the constant,
2763 if FORCE is nonzero. */
2765 bool
2766 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2768 int aligned_p;
2770 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2772 /* See if the target hook can handle this kind of object. */
2773 if (targetm.asm_out.integer (x, size, aligned_p))
2774 return true;
2776 /* If the object is a multi-byte one, try splitting it up. Split
2777 it into words it if is multi-word, otherwise split it into bytes. */
2778 if (size > 1)
2780 machine_mode omode, imode;
2781 unsigned int subalign;
2782 unsigned int subsize, i;
2783 enum mode_class mclass;
2785 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2786 subalign = MIN (align, subsize * BITS_PER_UNIT);
2787 if (GET_CODE (x) == CONST_FIXED)
2788 mclass = GET_MODE_CLASS (GET_MODE (x));
2789 else
2790 mclass = MODE_INT;
2792 omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0).require ();
2793 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0).require ();
2795 for (i = 0; i < size; i += subsize)
2797 rtx partial = simplify_subreg (omode, x, imode, i);
2798 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2799 break;
2801 if (i == size)
2802 return true;
2804 /* If we've printed some of it, but not all of it, there's no going
2805 back now. */
2806 gcc_assert (!i);
2809 gcc_assert (!force);
2811 return false;
2814 /* Assemble the floating-point constant D into an object of size MODE. ALIGN
2815 is the alignment of the constant in bits. If REVERSE is true, D is output
2816 in reverse storage order. */
2818 void
2819 assemble_real (REAL_VALUE_TYPE d, scalar_float_mode mode, unsigned int align,
2820 bool reverse)
2822 long data[4] = {0, 0, 0, 0};
2823 int bitsize, nelts, nunits, units_per;
2824 rtx elt;
2826 /* This is hairy. We have a quantity of known size. real_to_target
2827 will put it into an array of *host* longs, 32 bits per element
2828 (even if long is more than 32 bits). We need to determine the
2829 number of array elements that are occupied (nelts) and the number
2830 of *target* min-addressable units that will be occupied in the
2831 object file (nunits). We cannot assume that 32 divides the
2832 mode's bitsize (size * BITS_PER_UNIT) evenly.
2834 size * BITS_PER_UNIT is used here to make sure that padding bits
2835 (which might appear at either end of the value; real_to_target
2836 will include the padding bits in its output array) are included. */
2838 nunits = GET_MODE_SIZE (mode);
2839 bitsize = nunits * BITS_PER_UNIT;
2840 nelts = CEIL (bitsize, 32);
2841 units_per = 32 / BITS_PER_UNIT;
2843 real_to_target (data, &d, mode);
2845 /* Put out the first word with the specified alignment. */
2846 if (reverse)
2847 elt = flip_storage_order (SImode, gen_int_mode (data[nelts - 1], SImode));
2848 else
2849 elt = GEN_INT (data[0]);
2850 assemble_integer (elt, MIN (nunits, units_per), align, 1);
2851 nunits -= units_per;
2853 /* Subsequent words need only 32-bit alignment. */
2854 align = min_align (align, 32);
2856 for (int i = 1; i < nelts; i++)
2858 if (reverse)
2859 elt = flip_storage_order (SImode,
2860 gen_int_mode (data[nelts - 1 - i], SImode));
2861 else
2862 elt = GEN_INT (data[i]);
2863 assemble_integer (elt, MIN (nunits, units_per), align, 1);
2864 nunits -= units_per;
2868 /* Given an expression EXP with a constant value,
2869 reduce it to the sum of an assembler symbol and an integer.
2870 Store them both in the structure *VALUE.
2871 EXP must be reducible. */
2873 struct addr_const {
2874 rtx base;
2875 HOST_WIDE_INT offset;
2878 static void
2879 decode_addr_const (tree exp, struct addr_const *value)
2881 tree target = TREE_OPERAND (exp, 0);
2882 HOST_WIDE_INT offset = 0;
2883 rtx x;
2885 while (1)
2887 if (TREE_CODE (target) == COMPONENT_REF
2888 && tree_fits_shwi_p (byte_position (TREE_OPERAND (target, 1))))
2890 offset += int_byte_position (TREE_OPERAND (target, 1));
2891 target = TREE_OPERAND (target, 0);
2893 else if (TREE_CODE (target) == ARRAY_REF
2894 || TREE_CODE (target) == ARRAY_RANGE_REF)
2896 /* Truncate big offset. */
2897 offset += (TREE_INT_CST_LOW (TYPE_SIZE_UNIT (TREE_TYPE (target)))
2898 * TREE_INT_CST_LOW (TREE_OPERAND (target, 1)));
2899 target = TREE_OPERAND (target, 0);
2901 else if (TREE_CODE (target) == MEM_REF
2902 && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR)
2904 offset += mem_ref_offset (target).to_short_addr ();
2905 target = TREE_OPERAND (TREE_OPERAND (target, 0), 0);
2907 else if (TREE_CODE (target) == INDIRECT_REF
2908 && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR
2909 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0))
2910 == ADDR_EXPR)
2911 target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0);
2912 else
2913 break;
2916 switch (TREE_CODE (target))
2918 case VAR_DECL:
2919 case FUNCTION_DECL:
2920 x = DECL_RTL (target);
2921 break;
2923 case LABEL_DECL:
2924 x = gen_rtx_MEM (FUNCTION_MODE,
2925 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2926 break;
2928 case REAL_CST:
2929 case FIXED_CST:
2930 case STRING_CST:
2931 case COMPLEX_CST:
2932 case CONSTRUCTOR:
2933 case INTEGER_CST:
2934 x = output_constant_def (target, 1);
2935 break;
2937 case INDIRECT_REF:
2938 /* This deals with absolute addresses. */
2939 offset += tree_to_shwi (TREE_OPERAND (target, 0));
2940 x = gen_rtx_MEM (QImode,
2941 gen_rtx_SYMBOL_REF (Pmode, "origin of addresses"));
2942 break;
2944 default:
2945 gcc_unreachable ();
2948 gcc_assert (MEM_P (x));
2949 x = XEXP (x, 0);
2951 value->base = x;
2952 value->offset = offset;
2955 static GTY(()) hash_table<tree_descriptor_hasher> *const_desc_htab;
2957 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2959 /* Constant pool accessor function. */
2961 hash_table<tree_descriptor_hasher> *
2962 constant_pool_htab (void)
2964 return const_desc_htab;
2967 /* Compute a hash code for a constant expression. */
2969 hashval_t
2970 tree_descriptor_hasher::hash (constant_descriptor_tree *ptr)
2972 return ptr->hash;
2975 static hashval_t
2976 const_hash_1 (const tree exp)
2978 const char *p;
2979 hashval_t hi;
2980 int len, i;
2981 enum tree_code code = TREE_CODE (exp);
2983 /* Either set P and LEN to the address and len of something to hash and
2984 exit the switch or return a value. */
2986 switch (code)
2988 case INTEGER_CST:
2989 p = (char *) &TREE_INT_CST_ELT (exp, 0);
2990 len = TREE_INT_CST_NUNITS (exp) * sizeof (HOST_WIDE_INT);
2991 break;
2993 case REAL_CST:
2994 return real_hash (TREE_REAL_CST_PTR (exp));
2996 case FIXED_CST:
2997 return fixed_hash (TREE_FIXED_CST_PTR (exp));
2999 case STRING_CST:
3000 p = TREE_STRING_POINTER (exp);
3001 len = TREE_STRING_LENGTH (exp);
3002 break;
3004 case COMPLEX_CST:
3005 return (const_hash_1 (TREE_REALPART (exp)) * 5
3006 + const_hash_1 (TREE_IMAGPART (exp)));
3008 case VECTOR_CST:
3010 unsigned i;
3012 hi = 7 + VECTOR_CST_NELTS (exp);
3014 for (i = 0; i < VECTOR_CST_NELTS (exp); ++i)
3015 hi = hi * 563 + const_hash_1 (VECTOR_CST_ELT (exp, i));
3017 return hi;
3020 case CONSTRUCTOR:
3022 unsigned HOST_WIDE_INT idx;
3023 tree value;
3025 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
3027 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
3028 if (value)
3029 hi = hi * 603 + const_hash_1 (value);
3031 return hi;
3034 case ADDR_EXPR:
3035 case FDESC_EXPR:
3037 struct addr_const value;
3039 decode_addr_const (exp, &value);
3040 switch (GET_CODE (value.base))
3042 case SYMBOL_REF:
3043 /* Don't hash the address of the SYMBOL_REF;
3044 only use the offset and the symbol name. */
3045 hi = value.offset;
3046 p = XSTR (value.base, 0);
3047 for (i = 0; p[i] != 0; i++)
3048 hi = ((hi * 613) + (unsigned) (p[i]));
3049 break;
3051 case LABEL_REF:
3052 hi = (value.offset
3053 + CODE_LABEL_NUMBER (label_ref_label (value.base)) * 13);
3054 break;
3056 default:
3057 gcc_unreachable ();
3060 return hi;
3062 case PLUS_EXPR:
3063 case POINTER_PLUS_EXPR:
3064 case MINUS_EXPR:
3065 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
3066 + const_hash_1 (TREE_OPERAND (exp, 1)));
3068 CASE_CONVERT:
3069 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
3071 default:
3072 /* A language specific constant. Just hash the code. */
3073 return code;
3076 /* Compute hashing function. */
3077 hi = len;
3078 for (i = 0; i < len; i++)
3079 hi = ((hi * 613) + (unsigned) (p[i]));
3081 return hi;
3084 /* Wrapper of compare_constant, for the htab interface. */
3085 bool
3086 tree_descriptor_hasher::equal (constant_descriptor_tree *c1,
3087 constant_descriptor_tree *c2)
3089 if (c1->hash != c2->hash)
3090 return 0;
3091 return compare_constant (c1->value, c2->value);
3094 /* Compare t1 and t2, and return 1 only if they are known to result in
3095 the same bit pattern on output. */
3097 static int
3098 compare_constant (const tree t1, const tree t2)
3100 enum tree_code typecode;
3102 if (t1 == NULL_TREE)
3103 return t2 == NULL_TREE;
3104 if (t2 == NULL_TREE)
3105 return 0;
3107 if (TREE_CODE (t1) != TREE_CODE (t2))
3108 return 0;
3110 switch (TREE_CODE (t1))
3112 case INTEGER_CST:
3113 /* Integer constants are the same only if the same width of type. */
3114 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3115 return 0;
3116 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3117 return 0;
3118 return tree_int_cst_equal (t1, t2);
3120 case REAL_CST:
3121 /* Real constants are the same only if the same width of type. */
3122 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3123 return 0;
3125 return real_identical (&TREE_REAL_CST (t1), &TREE_REAL_CST (t2));
3127 case FIXED_CST:
3128 /* Fixed constants are the same only if the same width of type. */
3129 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3130 return 0;
3132 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
3134 case STRING_CST:
3135 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3136 return 0;
3138 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
3139 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
3140 TREE_STRING_LENGTH (t1)));
3142 case COMPLEX_CST:
3143 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
3144 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
3146 case VECTOR_CST:
3148 unsigned i;
3150 if (VECTOR_CST_NELTS (t1) != VECTOR_CST_NELTS (t2))
3151 return 0;
3153 for (i = 0; i < VECTOR_CST_NELTS (t1); ++i)
3154 if (!compare_constant (VECTOR_CST_ELT (t1, i),
3155 VECTOR_CST_ELT (t2, i)))
3156 return 0;
3158 return 1;
3161 case CONSTRUCTOR:
3163 vec<constructor_elt, va_gc> *v1, *v2;
3164 unsigned HOST_WIDE_INT idx;
3166 typecode = TREE_CODE (TREE_TYPE (t1));
3167 if (typecode != TREE_CODE (TREE_TYPE (t2)))
3168 return 0;
3170 if (typecode == ARRAY_TYPE)
3172 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
3173 /* For arrays, check that mode, size and storage order match. */
3174 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
3175 || size_1 == -1
3176 || size_1 != int_size_in_bytes (TREE_TYPE (t2))
3177 || TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (t1))
3178 != TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (t2)))
3179 return 0;
3181 else
3183 /* For record and union constructors, require exact type
3184 equality. */
3185 if (TREE_TYPE (t1) != TREE_TYPE (t2))
3186 return 0;
3189 v1 = CONSTRUCTOR_ELTS (t1);
3190 v2 = CONSTRUCTOR_ELTS (t2);
3191 if (vec_safe_length (v1) != vec_safe_length (v2))
3192 return 0;
3194 for (idx = 0; idx < vec_safe_length (v1); ++idx)
3196 constructor_elt *c1 = &(*v1)[idx];
3197 constructor_elt *c2 = &(*v2)[idx];
3199 /* Check that each value is the same... */
3200 if (!compare_constant (c1->value, c2->value))
3201 return 0;
3202 /* ... and that they apply to the same fields! */
3203 if (typecode == ARRAY_TYPE)
3205 if (!compare_constant (c1->index, c2->index))
3206 return 0;
3208 else
3210 if (c1->index != c2->index)
3211 return 0;
3215 return 1;
3218 case ADDR_EXPR:
3219 case FDESC_EXPR:
3221 struct addr_const value1, value2;
3222 enum rtx_code code;
3223 int ret;
3225 decode_addr_const (t1, &value1);
3226 decode_addr_const (t2, &value2);
3228 if (value1.offset != value2.offset)
3229 return 0;
3231 code = GET_CODE (value1.base);
3232 if (code != GET_CODE (value2.base))
3233 return 0;
3235 switch (code)
3237 case SYMBOL_REF:
3238 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3239 break;
3241 case LABEL_REF:
3242 ret = (CODE_LABEL_NUMBER (label_ref_label (value1.base))
3243 == CODE_LABEL_NUMBER (label_ref_label (value2.base)));
3244 break;
3246 default:
3247 gcc_unreachable ();
3249 return ret;
3252 case PLUS_EXPR:
3253 case POINTER_PLUS_EXPR:
3254 case MINUS_EXPR:
3255 case RANGE_EXPR:
3256 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3257 && compare_constant (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3259 CASE_CONVERT:
3260 case VIEW_CONVERT_EXPR:
3261 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3263 default:
3264 return 0;
3267 gcc_unreachable ();
3270 /* Return the section into which constant EXP should be placed. */
3272 static section *
3273 get_constant_section (tree exp, unsigned int align)
3275 return targetm.asm_out.select_section (exp,
3276 compute_reloc_for_constant (exp),
3277 align);
3280 /* Return the size of constant EXP in bytes. */
3282 static HOST_WIDE_INT
3283 get_constant_size (tree exp)
3285 HOST_WIDE_INT size;
3287 size = int_size_in_bytes (TREE_TYPE (exp));
3288 if (TREE_CODE (exp) == STRING_CST)
3289 size = MAX (TREE_STRING_LENGTH (exp), size);
3290 return size;
3293 /* Subroutine of output_constant_def:
3294 No constant equal to EXP is known to have been output.
3295 Make a constant descriptor to enter EXP in the hash table.
3296 Assign the label number and construct RTL to refer to the
3297 constant's location in memory.
3298 Caller is responsible for updating the hash table. */
3300 static struct constant_descriptor_tree *
3301 build_constant_desc (tree exp)
3303 struct constant_descriptor_tree *desc;
3304 rtx symbol, rtl;
3305 char label[256];
3306 int labelno;
3307 tree decl;
3309 desc = ggc_alloc<constant_descriptor_tree> ();
3310 desc->value = exp;
3312 /* Create a string containing the label name, in LABEL. */
3313 labelno = const_labelno++;
3314 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3316 /* Construct the VAR_DECL associated with the constant. */
3317 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3318 TREE_TYPE (exp));
3319 DECL_ARTIFICIAL (decl) = 1;
3320 DECL_IGNORED_P (decl) = 1;
3321 TREE_READONLY (decl) = 1;
3322 TREE_STATIC (decl) = 1;
3323 TREE_ADDRESSABLE (decl) = 1;
3324 /* We don't set the RTL yet as this would cause varpool to assume that the
3325 variable is referenced. Moreover, it would just be dropped in LTO mode.
3326 Instead we set the flag that will be recognized in make_decl_rtl. */
3327 DECL_IN_CONSTANT_POOL (decl) = 1;
3328 DECL_INITIAL (decl) = desc->value;
3329 /* ??? targetm.constant_alignment hasn't been updated for vector types on
3330 most architectures so use DATA_ALIGNMENT as well, except for strings. */
3331 if (TREE_CODE (exp) == STRING_CST)
3332 SET_DECL_ALIGN (decl, targetm.constant_alignment (exp, DECL_ALIGN (decl)));
3333 else
3334 align_variable (decl, 0);
3336 /* Now construct the SYMBOL_REF and the MEM. */
3337 if (use_object_blocks_p ())
3339 int align = (TREE_CODE (decl) == CONST_DECL
3340 || (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
3341 ? DECL_ALIGN (decl)
3342 : symtab_node::get (decl)->definition_alignment ());
3343 section *sect = get_constant_section (exp, align);
3344 symbol = create_block_symbol (ggc_strdup (label),
3345 get_block_for_section (sect), -1);
3347 else
3348 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3349 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3350 SET_SYMBOL_REF_DECL (symbol, decl);
3351 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3353 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3354 set_mem_attributes (rtl, exp, 1);
3355 set_mem_alias_set (rtl, 0);
3357 /* Putting EXP into the literal pool might have imposed a different
3358 alignment which should be visible in the RTX as well. */
3359 set_mem_align (rtl, DECL_ALIGN (decl));
3361 /* We cannot share RTX'es in pool entries.
3362 Mark this piece of RTL as required for unsharing. */
3363 RTX_FLAG (rtl, used) = 1;
3365 /* Set flags or add text to the name to record information, such as
3366 that it is a local symbol. If the name is changed, the macro
3367 ASM_OUTPUT_LABELREF will have to know how to strip this
3368 information. This call might invalidate our local variable
3369 SYMBOL; we can't use it afterward. */
3370 targetm.encode_section_info (exp, rtl, true);
3372 desc->rtl = rtl;
3374 return desc;
3377 /* Return an rtx representing a reference to constant data in memory
3378 for the constant expression EXP.
3380 If assembler code for such a constant has already been output,
3381 return an rtx to refer to it.
3382 Otherwise, output such a constant in memory
3383 and generate an rtx for it.
3385 If DEFER is nonzero, this constant can be deferred and output only
3386 if referenced in the function after all optimizations.
3388 `const_desc_table' records which constants already have label strings. */
3391 output_constant_def (tree exp, int defer)
3393 struct constant_descriptor_tree *desc;
3394 struct constant_descriptor_tree key;
3396 /* Look up EXP in the table of constant descriptors. If we didn't find
3397 it, create a new one. */
3398 key.value = exp;
3399 key.hash = const_hash_1 (exp);
3400 constant_descriptor_tree **loc
3401 = const_desc_htab->find_slot_with_hash (&key, key.hash, INSERT);
3403 desc = *loc;
3404 if (desc == 0)
3406 desc = build_constant_desc (exp);
3407 desc->hash = key.hash;
3408 *loc = desc;
3411 maybe_output_constant_def_contents (desc, defer);
3412 return desc->rtl;
3415 /* Subroutine of output_constant_def: Decide whether or not we need to
3416 output the constant DESC now, and if so, do it. */
3417 static void
3418 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3419 int defer)
3421 rtx symbol = XEXP (desc->rtl, 0);
3422 tree exp = desc->value;
3424 if (flag_syntax_only)
3425 return;
3427 if (TREE_ASM_WRITTEN (exp))
3428 /* Already output; don't do it again. */
3429 return;
3431 /* We can always defer constants as long as the context allows
3432 doing so. */
3433 if (defer)
3435 /* Increment n_deferred_constants if it exists. It needs to be at
3436 least as large as the number of constants actually referred to
3437 by the function. If it's too small we'll stop looking too early
3438 and fail to emit constants; if it's too large we'll only look
3439 through the entire function when we could have stopped earlier. */
3440 if (cfun)
3441 n_deferred_constants++;
3442 return;
3445 output_constant_def_contents (symbol);
3448 /* Subroutine of output_constant_def_contents. Output the definition
3449 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3450 constant's alignment in bits. */
3452 static void
3453 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3455 HOST_WIDE_INT size;
3457 size = get_constant_size (exp);
3459 /* Do any machine/system dependent processing of the constant. */
3460 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3462 /* Output the value of EXP. */
3463 output_constant (exp, size, align, false);
3465 targetm.asm_out.decl_end ();
3468 /* We must output the constant data referred to by SYMBOL; do so. */
3470 static void
3471 output_constant_def_contents (rtx symbol)
3473 tree decl = SYMBOL_REF_DECL (symbol);
3474 tree exp = DECL_INITIAL (decl);
3475 bool asan_protected = false;
3477 /* Make sure any other constants whose addresses appear in EXP
3478 are assigned label numbers. */
3479 output_addressed_constants (exp);
3481 /* We are no longer deferring this constant. */
3482 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3484 if ((flag_sanitize & SANITIZE_ADDRESS)
3485 && TREE_CODE (exp) == STRING_CST
3486 && asan_protect_global (exp))
3488 asan_protected = true;
3489 SET_DECL_ALIGN (decl, MAX (DECL_ALIGN (decl),
3490 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT));
3493 /* If the constant is part of an object block, make sure that the
3494 decl has been positioned within its block, but do not write out
3495 its definition yet. output_object_blocks will do that later. */
3496 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3497 place_block_symbol (symbol);
3498 else
3500 int align = (TREE_CODE (decl) == CONST_DECL
3501 || (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
3502 ? DECL_ALIGN (decl)
3503 : symtab_node::get (decl)->definition_alignment ());
3504 switch_to_section (get_constant_section (exp, align));
3505 if (align > BITS_PER_UNIT)
3506 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3507 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3508 if (asan_protected)
3510 HOST_WIDE_INT size = get_constant_size (exp);
3511 assemble_zeros (asan_red_zone_size (size));
3516 /* Look up EXP in the table of constant descriptors. Return the rtl
3517 if it has been emitted, else null. */
3520 lookup_constant_def (tree exp)
3522 struct constant_descriptor_tree key;
3524 key.value = exp;
3525 key.hash = const_hash_1 (exp);
3526 constant_descriptor_tree *desc
3527 = const_desc_htab->find_with_hash (&key, key.hash);
3529 return (desc ? desc->rtl : NULL_RTX);
3532 /* Return a tree representing a reference to constant data in memory
3533 for the constant expression EXP.
3535 This is the counterpart of output_constant_def at the Tree level. */
3537 tree
3538 tree_output_constant_def (tree exp)
3540 struct constant_descriptor_tree *desc, key;
3541 tree decl;
3543 /* Look up EXP in the table of constant descriptors. If we didn't find
3544 it, create a new one. */
3545 key.value = exp;
3546 key.hash = const_hash_1 (exp);
3547 constant_descriptor_tree **loc
3548 = const_desc_htab->find_slot_with_hash (&key, key.hash, INSERT);
3550 desc = *loc;
3551 if (desc == 0)
3553 desc = build_constant_desc (exp);
3554 desc->hash = key.hash;
3555 *loc = desc;
3558 decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3559 varpool_node::finalize_decl (decl);
3560 return decl;
3563 struct GTY((chain_next ("%h.next"), for_user)) constant_descriptor_rtx {
3564 struct constant_descriptor_rtx *next;
3565 rtx mem;
3566 rtx sym;
3567 rtx constant;
3568 HOST_WIDE_INT offset;
3569 hashval_t hash;
3570 fixed_size_mode mode;
3571 unsigned int align;
3572 int labelno;
3573 int mark;
3576 struct const_rtx_desc_hasher : ggc_ptr_hash<constant_descriptor_rtx>
3578 static hashval_t hash (constant_descriptor_rtx *);
3579 static bool equal (constant_descriptor_rtx *, constant_descriptor_rtx *);
3582 /* Used in the hash tables to avoid outputting the same constant
3583 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3584 are output once per function, not once per file. */
3585 /* ??? Only a few targets need per-function constant pools. Most
3586 can use one per-file pool. Should add a targetm bit to tell the
3587 difference. */
3589 struct GTY(()) rtx_constant_pool {
3590 /* Pointers to first and last constant in pool, as ordered by offset. */
3591 struct constant_descriptor_rtx *first;
3592 struct constant_descriptor_rtx *last;
3594 /* Hash facility for making memory-constants from constant rtl-expressions.
3595 It is used on RISC machines where immediate integer arguments and
3596 constant addresses are restricted so that such constants must be stored
3597 in memory. */
3598 hash_table<const_rtx_desc_hasher> *const_rtx_htab;
3600 /* Current offset in constant pool (does not include any
3601 machine-specific header). */
3602 HOST_WIDE_INT offset;
3605 /* Hash and compare functions for const_rtx_htab. */
3607 hashval_t
3608 const_rtx_desc_hasher::hash (constant_descriptor_rtx *desc)
3610 return desc->hash;
3613 bool
3614 const_rtx_desc_hasher::equal (constant_descriptor_rtx *x,
3615 constant_descriptor_rtx *y)
3617 if (x->mode != y->mode)
3618 return 0;
3619 return rtx_equal_p (x->constant, y->constant);
3622 /* Hash one component of a constant. */
3624 static hashval_t
3625 const_rtx_hash_1 (const_rtx x)
3627 unsigned HOST_WIDE_INT hwi;
3628 machine_mode mode;
3629 enum rtx_code code;
3630 hashval_t h;
3631 int i;
3633 code = GET_CODE (x);
3634 mode = GET_MODE (x);
3635 h = (hashval_t) code * 1048573 + mode;
3637 switch (code)
3639 case CONST_INT:
3640 hwi = INTVAL (x);
3642 fold_hwi:
3644 int shift = sizeof (hashval_t) * CHAR_BIT;
3645 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3647 h ^= (hashval_t) hwi;
3648 for (i = 1; i < n; ++i)
3650 hwi >>= shift;
3651 h ^= (hashval_t) hwi;
3654 break;
3656 case CONST_WIDE_INT:
3657 hwi = 0;
3659 for (i = 0; i < CONST_WIDE_INT_NUNITS (x); i++)
3660 hwi ^= CONST_WIDE_INT_ELT (x, i);
3661 goto fold_hwi;
3664 case CONST_DOUBLE:
3665 if (TARGET_SUPPORTS_WIDE_INT == 0 && mode == VOIDmode)
3667 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3668 goto fold_hwi;
3670 else
3671 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3672 break;
3674 case CONST_FIXED:
3675 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3676 break;
3678 case SYMBOL_REF:
3679 h ^= htab_hash_string (XSTR (x, 0));
3680 break;
3682 case LABEL_REF:
3683 h = h * 251 + CODE_LABEL_NUMBER (label_ref_label (x));
3684 break;
3686 case UNSPEC:
3687 case UNSPEC_VOLATILE:
3688 h = h * 251 + XINT (x, 1);
3689 break;
3691 default:
3692 break;
3695 return h;
3698 /* Compute a hash value for X, which should be a constant. */
3700 static hashval_t
3701 const_rtx_hash (rtx x)
3703 hashval_t h = 0;
3704 subrtx_iterator::array_type array;
3705 FOR_EACH_SUBRTX (iter, array, x, ALL)
3706 h = h * 509 + const_rtx_hash_1 (*iter);
3707 return h;
3711 /* Create and return a new rtx constant pool. */
3713 static struct rtx_constant_pool *
3714 create_constant_pool (void)
3716 struct rtx_constant_pool *pool;
3718 pool = ggc_alloc<rtx_constant_pool> ();
3719 pool->const_rtx_htab = hash_table<const_rtx_desc_hasher>::create_ggc (31);
3720 pool->first = NULL;
3721 pool->last = NULL;
3722 pool->offset = 0;
3723 return pool;
3726 /* Initialize constant pool hashing for a new function. */
3728 void
3729 init_varasm_status (void)
3731 crtl->varasm.pool = create_constant_pool ();
3732 crtl->varasm.deferred_constants = 0;
3735 /* Given a MINUS expression, simplify it if both sides
3736 include the same symbol. */
3739 simplify_subtraction (rtx x)
3741 rtx r = simplify_rtx (x);
3742 return r ? r : x;
3745 /* Given a constant rtx X, make (or find) a memory constant for its value
3746 and return a MEM rtx to refer to it in memory. IN_MODE is the mode
3747 of X. */
3750 force_const_mem (machine_mode in_mode, rtx x)
3752 struct constant_descriptor_rtx *desc, tmp;
3753 struct rtx_constant_pool *pool;
3754 char label[256];
3755 rtx def, symbol;
3756 hashval_t hash;
3757 unsigned int align;
3758 constant_descriptor_rtx **slot;
3759 fixed_size_mode mode;
3761 /* We can't force variable-sized objects to memory. */
3762 if (!is_a <fixed_size_mode> (in_mode, &mode))
3763 return NULL_RTX;
3765 /* If we're not allowed to drop X into the constant pool, don't. */
3766 if (targetm.cannot_force_const_mem (mode, x))
3767 return NULL_RTX;
3769 /* Record that this function has used a constant pool entry. */
3770 crtl->uses_const_pool = 1;
3772 /* Decide which pool to use. */
3773 pool = (targetm.use_blocks_for_constant_p (mode, x)
3774 ? shared_constant_pool
3775 : crtl->varasm.pool);
3777 /* Lookup the value in the hashtable. */
3778 tmp.constant = x;
3779 tmp.mode = mode;
3780 hash = const_rtx_hash (x);
3781 slot = pool->const_rtx_htab->find_slot_with_hash (&tmp, hash, INSERT);
3782 desc = *slot;
3784 /* If the constant was already present, return its memory. */
3785 if (desc)
3786 return copy_rtx (desc->mem);
3788 /* Otherwise, create a new descriptor. */
3789 desc = ggc_alloc<constant_descriptor_rtx> ();
3790 *slot = desc;
3792 /* Align the location counter as required by EXP's data type. */
3793 machine_mode align_mode = (mode == VOIDmode ? word_mode : mode);
3794 align = targetm.static_rtx_alignment (align_mode);
3796 pool->offset += (align / BITS_PER_UNIT) - 1;
3797 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3799 desc->next = NULL;
3800 desc->constant = copy_rtx (tmp.constant);
3801 desc->offset = pool->offset;
3802 desc->hash = hash;
3803 desc->mode = mode;
3804 desc->align = align;
3805 desc->labelno = const_labelno;
3806 desc->mark = 0;
3808 pool->offset += GET_MODE_SIZE (mode);
3809 if (pool->last)
3810 pool->last->next = desc;
3811 else
3812 pool->first = pool->last = desc;
3813 pool->last = desc;
3815 /* Create a string containing the label name, in LABEL. */
3816 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3817 ++const_labelno;
3819 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3820 the constants pool. */
3821 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3823 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3824 symbol = create_block_symbol (ggc_strdup (label),
3825 get_block_for_section (sect), -1);
3827 else
3828 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3829 desc->sym = symbol;
3830 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3831 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3832 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3834 /* Construct the MEM. */
3835 desc->mem = def = gen_const_mem (mode, symbol);
3836 set_mem_align (def, align);
3838 /* If we're dropping a label to the constant pool, make sure we
3839 don't delete it. */
3840 if (GET_CODE (x) == LABEL_REF)
3841 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3843 return copy_rtx (def);
3846 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3849 get_pool_constant (const_rtx addr)
3851 return SYMBOL_REF_CONSTANT (addr)->constant;
3854 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3855 and whether it has been output or not. */
3858 get_pool_constant_mark (rtx addr, bool *pmarked)
3860 struct constant_descriptor_rtx *desc;
3862 desc = SYMBOL_REF_CONSTANT (addr);
3863 *pmarked = (desc->mark != 0);
3864 return desc->constant;
3867 /* Similar, return the mode. */
3869 fixed_size_mode
3870 get_pool_mode (const_rtx addr)
3872 return SYMBOL_REF_CONSTANT (addr)->mode;
3875 /* Return TRUE if and only if the constant pool has no entries. Note
3876 that even entries we might end up choosing not to emit are counted
3877 here, so there is the potential for missed optimizations. */
3879 bool
3880 constant_pool_empty_p (void)
3882 return crtl->varasm.pool->first == NULL;
3885 /* Worker function for output_constant_pool_1. Emit assembly for X
3886 in MODE with known alignment ALIGN. */
3888 static void
3889 output_constant_pool_2 (fixed_size_mode mode, rtx x, unsigned int align)
3891 switch (GET_MODE_CLASS (mode))
3893 case MODE_FLOAT:
3894 case MODE_DECIMAL_FLOAT:
3896 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3897 assemble_real (*CONST_DOUBLE_REAL_VALUE (x),
3898 as_a <scalar_float_mode> (mode), align, false);
3899 break;
3902 case MODE_INT:
3903 case MODE_PARTIAL_INT:
3904 case MODE_FRACT:
3905 case MODE_UFRACT:
3906 case MODE_ACCUM:
3907 case MODE_UACCUM:
3908 case MODE_POINTER_BOUNDS:
3909 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3910 break;
3912 case MODE_VECTOR_FLOAT:
3913 case MODE_VECTOR_INT:
3914 case MODE_VECTOR_FRACT:
3915 case MODE_VECTOR_UFRACT:
3916 case MODE_VECTOR_ACCUM:
3917 case MODE_VECTOR_UACCUM:
3919 int i, units;
3920 scalar_mode submode = GET_MODE_INNER (mode);
3921 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3923 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3924 units = CONST_VECTOR_NUNITS (x);
3926 for (i = 0; i < units; i++)
3928 rtx elt = CONST_VECTOR_ELT (x, i);
3929 output_constant_pool_2 (submode, elt, i ? subalign : align);
3932 break;
3934 default:
3935 gcc_unreachable ();
3939 /* Worker function for output_constant_pool. Emit constant DESC,
3940 giving it ALIGN bits of alignment. */
3942 static void
3943 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3944 unsigned int align)
3946 rtx x, tmp;
3948 x = desc->constant;
3950 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3951 whose CODE_LABEL has been deleted. This can occur if a jump table
3952 is eliminated by optimization. If so, write a constant of zero
3953 instead. Note that this can also happen by turning the
3954 CODE_LABEL into a NOTE. */
3955 /* ??? This seems completely and utterly wrong. Certainly it's
3956 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3957 functioning even with rtx_insn::deleted and friends. */
3959 tmp = x;
3960 switch (GET_CODE (tmp))
3962 case CONST:
3963 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3964 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
3965 break;
3966 tmp = XEXP (XEXP (tmp, 0), 0);
3967 /* FALLTHRU */
3969 case LABEL_REF:
3971 rtx_insn *insn = label_ref_label (tmp);
3972 gcc_assert (!insn->deleted ());
3973 gcc_assert (!NOTE_P (insn)
3974 || NOTE_KIND (insn) != NOTE_INSN_DELETED);
3975 break;
3978 default:
3979 break;
3982 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3983 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3984 align, desc->labelno, done);
3985 #endif
3987 assemble_align (align);
3989 /* Output the label. */
3990 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3992 /* Output the data.
3993 Pass actual alignment value while emitting string constant to asm code
3994 as function 'output_constant_pool_1' explicitly passes the alignment as 1
3995 assuming that the data is already aligned which prevents the generation
3996 of fix-up table entries. */
3997 output_constant_pool_2 (desc->mode, x, desc->align);
3999 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
4000 sections have proper size. */
4001 if (align > GET_MODE_BITSIZE (desc->mode)
4002 && in_section
4003 && (in_section->common.flags & SECTION_MERGE))
4004 assemble_align (align);
4006 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
4007 done:
4008 #endif
4009 return;
4012 /* Recompute the offsets of entries in POOL, and the overall size of
4013 POOL. Do this after calling mark_constant_pool to ensure that we
4014 are computing the offset values for the pool which we will actually
4015 emit. */
4017 static void
4018 recompute_pool_offsets (struct rtx_constant_pool *pool)
4020 struct constant_descriptor_rtx *desc;
4021 pool->offset = 0;
4023 for (desc = pool->first; desc ; desc = desc->next)
4024 if (desc->mark)
4026 /* Recalculate offset. */
4027 unsigned int align = desc->align;
4028 pool->offset += (align / BITS_PER_UNIT) - 1;
4029 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
4030 desc->offset = pool->offset;
4031 pool->offset += GET_MODE_SIZE (desc->mode);
4035 /* Mark all constants that are referenced by SYMBOL_REFs in X.
4036 Emit referenced deferred strings. */
4038 static void
4039 mark_constants_in_pattern (rtx insn)
4041 subrtx_iterator::array_type array;
4042 FOR_EACH_SUBRTX (iter, array, PATTERN (insn), ALL)
4044 const_rtx x = *iter;
4045 if (GET_CODE (x) == SYMBOL_REF)
4047 if (CONSTANT_POOL_ADDRESS_P (x))
4049 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
4050 if (desc->mark == 0)
4052 desc->mark = 1;
4053 iter.substitute (desc->constant);
4056 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
4058 tree decl = SYMBOL_REF_DECL (x);
4059 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
4061 n_deferred_constants--;
4062 output_constant_def_contents (CONST_CAST_RTX (x));
4069 /* Look through appropriate parts of INSN, marking all entries in the
4070 constant pool which are actually being used. Entries that are only
4071 referenced by other constants are also marked as used. Emit
4072 deferred strings that are used. */
4074 static void
4075 mark_constants (rtx_insn *insn)
4077 if (!INSN_P (insn))
4078 return;
4080 /* Insns may appear inside a SEQUENCE. Only check the patterns of
4081 insns, not any notes that may be attached. We don't want to mark
4082 a constant just because it happens to appear in a REG_EQUIV note. */
4083 if (rtx_sequence *seq = dyn_cast <rtx_sequence *> (PATTERN (insn)))
4085 int i, n = seq->len ();
4086 for (i = 0; i < n; ++i)
4088 rtx subinsn = seq->element (i);
4089 if (INSN_P (subinsn))
4090 mark_constants_in_pattern (subinsn);
4093 else
4094 mark_constants_in_pattern (insn);
4097 /* Look through the instructions for this function, and mark all the
4098 entries in POOL which are actually being used. Emit deferred constants
4099 which have indeed been used. */
4101 static void
4102 mark_constant_pool (void)
4104 rtx_insn *insn;
4106 if (!crtl->uses_const_pool && n_deferred_constants == 0)
4107 return;
4109 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4110 mark_constants (insn);
4113 /* Write all the constants in POOL. */
4115 static void
4116 output_constant_pool_contents (struct rtx_constant_pool *pool)
4118 struct constant_descriptor_rtx *desc;
4120 for (desc = pool->first; desc ; desc = desc->next)
4121 if (desc->mark)
4123 /* If the constant is part of an object_block, make sure that
4124 the constant has been positioned within its block, but do not
4125 write out its definition yet. output_object_blocks will do
4126 that later. */
4127 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
4128 && SYMBOL_REF_BLOCK (desc->sym))
4129 place_block_symbol (desc->sym);
4130 else
4132 switch_to_section (targetm.asm_out.select_rtx_section
4133 (desc->mode, desc->constant, desc->align));
4134 output_constant_pool_1 (desc, desc->align);
4139 /* Mark all constants that are used in the current function, then write
4140 out the function's private constant pool. */
4142 static void
4143 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
4144 tree fndecl ATTRIBUTE_UNUSED)
4146 struct rtx_constant_pool *pool = crtl->varasm.pool;
4148 /* It is possible for gcc to call force_const_mem and then to later
4149 discard the instructions which refer to the constant. In such a
4150 case we do not need to output the constant. */
4151 mark_constant_pool ();
4153 /* Having marked the constant pool entries we'll actually emit, we
4154 now need to rebuild the offset information, which may have become
4155 stale. */
4156 recompute_pool_offsets (pool);
4158 #ifdef ASM_OUTPUT_POOL_PROLOGUE
4159 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
4160 #endif
4162 output_constant_pool_contents (pool);
4164 #ifdef ASM_OUTPUT_POOL_EPILOGUE
4165 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
4166 #endif
4169 /* Write the contents of the shared constant pool. */
4171 void
4172 output_shared_constant_pool (void)
4174 output_constant_pool_contents (shared_constant_pool);
4177 /* Determine what kind of relocations EXP may need. */
4180 compute_reloc_for_constant (tree exp)
4182 int reloc = 0, reloc2;
4183 tree tem;
4185 switch (TREE_CODE (exp))
4187 case ADDR_EXPR:
4188 case FDESC_EXPR:
4189 /* Go inside any operations that get_inner_reference can handle and see
4190 if what's inside is a constant: no need to do anything here for
4191 addresses of variables or functions. */
4192 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4193 tem = TREE_OPERAND (tem, 0))
4196 if (TREE_CODE (tem) == MEM_REF
4197 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4199 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4200 break;
4203 if (!targetm.binds_local_p (tem))
4204 reloc |= 2;
4205 else
4206 reloc |= 1;
4207 break;
4209 case PLUS_EXPR:
4210 case POINTER_PLUS_EXPR:
4211 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4212 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4213 break;
4215 case MINUS_EXPR:
4216 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4217 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4218 /* The difference of two local labels is computable at link time. */
4219 if (reloc == 1 && reloc2 == 1)
4220 reloc = 0;
4221 else
4222 reloc |= reloc2;
4223 break;
4225 CASE_CONVERT:
4226 case VIEW_CONVERT_EXPR:
4227 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4228 break;
4230 case CONSTRUCTOR:
4232 unsigned HOST_WIDE_INT idx;
4233 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4234 if (tem != 0)
4235 reloc |= compute_reloc_for_constant (tem);
4237 break;
4239 default:
4240 break;
4242 return reloc;
4245 /* Find all the constants whose addresses are referenced inside of EXP,
4246 and make sure assembler code with a label has been output for each one.
4247 Indicate whether an ADDR_EXPR has been encountered. */
4249 static void
4250 output_addressed_constants (tree exp)
4252 tree tem;
4254 switch (TREE_CODE (exp))
4256 case ADDR_EXPR:
4257 case FDESC_EXPR:
4258 /* Go inside any operations that get_inner_reference can handle and see
4259 if what's inside is a constant: no need to do anything here for
4260 addresses of variables or functions. */
4261 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4262 tem = TREE_OPERAND (tem, 0))
4265 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4266 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4267 tem = DECL_INITIAL (tem);
4269 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4270 output_constant_def (tem, 0);
4272 if (TREE_CODE (tem) == MEM_REF)
4273 output_addressed_constants (TREE_OPERAND (tem, 0));
4274 break;
4276 case PLUS_EXPR:
4277 case POINTER_PLUS_EXPR:
4278 case MINUS_EXPR:
4279 output_addressed_constants (TREE_OPERAND (exp, 1));
4280 gcc_fallthrough ();
4282 CASE_CONVERT:
4283 case VIEW_CONVERT_EXPR:
4284 output_addressed_constants (TREE_OPERAND (exp, 0));
4285 break;
4287 case CONSTRUCTOR:
4289 unsigned HOST_WIDE_INT idx;
4290 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4291 if (tem != 0)
4292 output_addressed_constants (tem);
4294 break;
4296 default:
4297 break;
4301 /* Whether a constructor CTOR is a valid static constant initializer if all
4302 its elements are. This used to be internal to initializer_constant_valid_p
4303 and has been exposed to let other functions like categorize_ctor_elements
4304 evaluate the property while walking a constructor for other purposes. */
4306 bool
4307 constructor_static_from_elts_p (const_tree ctor)
4309 return (TREE_CONSTANT (ctor)
4310 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4311 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4312 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4315 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4316 tree *cache);
4318 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4319 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4320 which are valid when ENDTYPE is an integer of any size; in
4321 particular, this does not accept a pointer minus a constant. This
4322 returns null_pointer_node if the VALUE is an absolute constant
4323 which can be used to initialize a static variable. Otherwise it
4324 returns NULL. */
4326 static tree
4327 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4329 tree op0, op1;
4331 if (!INTEGRAL_TYPE_P (endtype))
4332 return NULL_TREE;
4334 op0 = TREE_OPERAND (value, 0);
4335 op1 = TREE_OPERAND (value, 1);
4337 /* Like STRIP_NOPS except allow the operand mode to widen. This
4338 works around a feature of fold that simplifies (int)(p1 - p2) to
4339 ((int)p1 - (int)p2) under the theory that the narrower operation
4340 is cheaper. */
4342 while (CONVERT_EXPR_P (op0)
4343 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4345 tree inner = TREE_OPERAND (op0, 0);
4346 if (inner == error_mark_node
4347 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4348 || (GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (op0)))
4349 > GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (inner)))))
4350 break;
4351 op0 = inner;
4354 while (CONVERT_EXPR_P (op1)
4355 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4357 tree inner = TREE_OPERAND (op1, 0);
4358 if (inner == error_mark_node
4359 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4360 || (GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (op1)))
4361 > GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (inner)))))
4362 break;
4363 op1 = inner;
4366 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4367 if (!op0)
4368 return NULL_TREE;
4370 op1 = initializer_constant_valid_p_1 (op1, endtype,
4371 cache ? cache + 2 : NULL);
4372 /* Both initializers must be known. */
4373 if (op1)
4375 if (op0 == op1
4376 && (op0 == null_pointer_node
4377 || TREE_CODE (value) == MINUS_EXPR))
4378 return null_pointer_node;
4380 /* Support differences between labels. */
4381 if (TREE_CODE (op0) == LABEL_DECL
4382 && TREE_CODE (op1) == LABEL_DECL)
4383 return null_pointer_node;
4385 if (TREE_CODE (op0) == STRING_CST
4386 && TREE_CODE (op1) == STRING_CST
4387 && operand_equal_p (op0, op1, 1))
4388 return null_pointer_node;
4391 return NULL_TREE;
4394 /* Helper function of initializer_constant_valid_p.
4395 Return nonzero if VALUE is a valid constant-valued expression
4396 for use in initializing a static variable; one that can be an
4397 element of a "constant" initializer.
4399 Return null_pointer_node if the value is absolute;
4400 if it is relocatable, return the variable that determines the relocation.
4401 We assume that VALUE has been folded as much as possible;
4402 therefore, we do not need to check for such things as
4403 arithmetic-combinations of integers.
4405 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4407 static tree
4408 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4410 tree ret;
4412 switch (TREE_CODE (value))
4414 case CONSTRUCTOR:
4415 if (constructor_static_from_elts_p (value))
4417 unsigned HOST_WIDE_INT idx;
4418 tree elt;
4419 bool absolute = true;
4421 if (cache && cache[0] == value)
4422 return cache[1];
4423 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4425 tree reloc;
4426 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4427 NULL);
4428 if (!reloc
4429 /* An absolute value is required with reverse SSO. */
4430 || (reloc != null_pointer_node
4431 && TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (value))
4432 && !AGGREGATE_TYPE_P (TREE_TYPE (elt))))
4434 if (cache)
4436 cache[0] = value;
4437 cache[1] = NULL_TREE;
4439 return NULL_TREE;
4441 if (reloc != null_pointer_node)
4442 absolute = false;
4444 /* For a non-absolute relocation, there is no single
4445 variable that can be "the variable that determines the
4446 relocation." */
4447 if (cache)
4449 cache[0] = value;
4450 cache[1] = absolute ? null_pointer_node : error_mark_node;
4452 return absolute ? null_pointer_node : error_mark_node;
4455 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4457 case INTEGER_CST:
4458 case VECTOR_CST:
4459 case REAL_CST:
4460 case FIXED_CST:
4461 case STRING_CST:
4462 case COMPLEX_CST:
4463 return null_pointer_node;
4465 case ADDR_EXPR:
4466 case FDESC_EXPR:
4468 tree op0 = staticp (TREE_OPERAND (value, 0));
4469 if (op0)
4471 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4472 to be a constant, this is old-skool offsetof-like nonsense. */
4473 if (TREE_CODE (op0) == INDIRECT_REF
4474 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4475 return null_pointer_node;
4476 /* Taking the address of a nested function involves a trampoline,
4477 unless we don't need or want one. */
4478 if (TREE_CODE (op0) == FUNCTION_DECL
4479 && DECL_STATIC_CHAIN (op0)
4480 && !TREE_NO_TRAMPOLINE (value))
4481 return NULL_TREE;
4482 /* "&{...}" requires a temporary to hold the constructed
4483 object. */
4484 if (TREE_CODE (op0) == CONSTRUCTOR)
4485 return NULL_TREE;
4487 return op0;
4490 case NON_LVALUE_EXPR:
4491 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4492 endtype, cache);
4494 case VIEW_CONVERT_EXPR:
4496 tree src = TREE_OPERAND (value, 0);
4497 tree src_type = TREE_TYPE (src);
4498 tree dest_type = TREE_TYPE (value);
4500 /* Allow view-conversions from aggregate to non-aggregate type only
4501 if the bit pattern is fully preserved afterwards; otherwise, the
4502 RTL expander won't be able to apply a subsequent transformation
4503 to the underlying constructor. */
4504 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4506 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4507 return initializer_constant_valid_p_1 (src, endtype, cache);
4508 else
4509 return NULL_TREE;
4512 /* Allow all other kinds of view-conversion. */
4513 return initializer_constant_valid_p_1 (src, endtype, cache);
4516 CASE_CONVERT:
4518 tree src = TREE_OPERAND (value, 0);
4519 tree src_type = TREE_TYPE (src);
4520 tree dest_type = TREE_TYPE (value);
4522 /* Allow conversions between pointer types, floating-point
4523 types, and offset types. */
4524 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4525 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4526 || (TREE_CODE (dest_type) == OFFSET_TYPE
4527 && TREE_CODE (src_type) == OFFSET_TYPE))
4528 return initializer_constant_valid_p_1 (src, endtype, cache);
4530 /* Allow length-preserving conversions between integer types. */
4531 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4532 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4533 return initializer_constant_valid_p_1 (src, endtype, cache);
4535 /* Allow conversions between other integer types only if
4536 explicit value. Don't allow sign-extension to a type larger
4537 than word and pointer, there aren't relocations that would
4538 allow to sign extend it to a wider type. */
4539 if (INTEGRAL_TYPE_P (dest_type)
4540 && INTEGRAL_TYPE_P (src_type)
4541 && (TYPE_UNSIGNED (src_type)
4542 || TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type)
4543 || TYPE_PRECISION (dest_type) <= BITS_PER_WORD
4544 || TYPE_PRECISION (dest_type) <= POINTER_SIZE))
4546 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4547 if (inner == null_pointer_node)
4548 return null_pointer_node;
4549 break;
4552 /* Allow (int) &foo provided int is as wide as a pointer. */
4553 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4554 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4555 return initializer_constant_valid_p_1 (src, endtype, cache);
4557 /* Likewise conversions from int to pointers, but also allow
4558 conversions from 0. */
4559 if ((POINTER_TYPE_P (dest_type)
4560 || TREE_CODE (dest_type) == OFFSET_TYPE)
4561 && INTEGRAL_TYPE_P (src_type))
4563 if (TREE_CODE (src) == INTEGER_CST
4564 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4565 return null_pointer_node;
4566 if (integer_zerop (src))
4567 return null_pointer_node;
4568 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4569 return initializer_constant_valid_p_1 (src, endtype, cache);
4572 /* Allow conversions to struct or union types if the value
4573 inside is okay. */
4574 if (TREE_CODE (dest_type) == RECORD_TYPE
4575 || TREE_CODE (dest_type) == UNION_TYPE)
4576 return initializer_constant_valid_p_1 (src, endtype, cache);
4578 break;
4580 case POINTER_PLUS_EXPR:
4581 case PLUS_EXPR:
4582 /* Any valid floating-point constants will have been folded by now;
4583 with -frounding-math we hit this with addition of two constants. */
4584 if (TREE_CODE (endtype) == REAL_TYPE)
4585 return NULL_TREE;
4586 if (cache && cache[0] == value)
4587 return cache[1];
4588 if (! INTEGRAL_TYPE_P (endtype)
4589 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4591 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4592 tree valid0
4593 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4594 endtype, ncache);
4595 tree valid1
4596 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4597 endtype, ncache + 2);
4598 /* If either term is absolute, use the other term's relocation. */
4599 if (valid0 == null_pointer_node)
4600 ret = valid1;
4601 else if (valid1 == null_pointer_node)
4602 ret = valid0;
4603 /* Support narrowing pointer differences. */
4604 else
4605 ret = narrowing_initializer_constant_valid_p (value, endtype,
4606 ncache);
4608 else
4609 /* Support narrowing pointer differences. */
4610 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4611 if (cache)
4613 cache[0] = value;
4614 cache[1] = ret;
4616 return ret;
4618 case POINTER_DIFF_EXPR:
4619 case MINUS_EXPR:
4620 if (TREE_CODE (endtype) == REAL_TYPE)
4621 return NULL_TREE;
4622 if (cache && cache[0] == value)
4623 return cache[1];
4624 if (! INTEGRAL_TYPE_P (endtype)
4625 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4627 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4628 tree valid0
4629 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4630 endtype, ncache);
4631 tree valid1
4632 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4633 endtype, ncache + 2);
4634 /* Win if second argument is absolute. */
4635 if (valid1 == null_pointer_node)
4636 ret = valid0;
4637 /* Win if both arguments have the same relocation.
4638 Then the value is absolute. */
4639 else if (valid0 == valid1 && valid0 != 0)
4640 ret = null_pointer_node;
4641 /* Since GCC guarantees that string constants are unique in the
4642 generated code, a subtraction between two copies of the same
4643 constant string is absolute. */
4644 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4645 && valid1 && TREE_CODE (valid1) == STRING_CST
4646 && operand_equal_p (valid0, valid1, 1))
4647 ret = null_pointer_node;
4648 /* Support narrowing differences. */
4649 else
4650 ret = narrowing_initializer_constant_valid_p (value, endtype,
4651 ncache);
4653 else
4654 /* Support narrowing differences. */
4655 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4656 if (cache)
4658 cache[0] = value;
4659 cache[1] = ret;
4661 return ret;
4663 default:
4664 break;
4667 return NULL_TREE;
4670 /* Return nonzero if VALUE is a valid constant-valued expression
4671 for use in initializing a static variable; one that can be an
4672 element of a "constant" initializer.
4674 Return null_pointer_node if the value is absolute;
4675 if it is relocatable, return the variable that determines the relocation.
4676 We assume that VALUE has been folded as much as possible;
4677 therefore, we do not need to check for such things as
4678 arithmetic-combinations of integers. */
4679 tree
4680 initializer_constant_valid_p (tree value, tree endtype, bool reverse)
4682 tree reloc = initializer_constant_valid_p_1 (value, endtype, NULL);
4684 /* An absolute value is required with reverse storage order. */
4685 if (reloc
4686 && reloc != null_pointer_node
4687 && reverse
4688 && !AGGREGATE_TYPE_P (endtype)
4689 && !VECTOR_TYPE_P (endtype))
4690 reloc = NULL_TREE;
4692 return reloc;
4695 /* Return true if VALUE is a valid constant-valued expression
4696 for use in initializing a static bit-field; one that can be
4697 an element of a "constant" initializer. */
4699 bool
4700 initializer_constant_valid_for_bitfield_p (tree value)
4702 /* For bitfields we support integer constants or possibly nested aggregates
4703 of such. */
4704 switch (TREE_CODE (value))
4706 case CONSTRUCTOR:
4708 unsigned HOST_WIDE_INT idx;
4709 tree elt;
4711 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4712 if (!initializer_constant_valid_for_bitfield_p (elt))
4713 return false;
4714 return true;
4717 case INTEGER_CST:
4718 case REAL_CST:
4719 return true;
4721 case VIEW_CONVERT_EXPR:
4722 case NON_LVALUE_EXPR:
4723 return
4724 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4726 default:
4727 break;
4730 return false;
4733 /* output_constructor outer state of relevance in recursive calls, typically
4734 for nested aggregate bitfields. */
4736 struct oc_outer_state {
4737 unsigned int bit_offset; /* current position in ... */
4738 int byte; /* ... the outer byte buffer. */
4741 static unsigned HOST_WIDE_INT
4742 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int, bool,
4743 oc_outer_state *);
4745 /* Output assembler code for constant EXP, with no label.
4746 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4747 Assumes output_addressed_constants has been done on EXP already.
4749 Generate at least SIZE bytes of assembler data, padding at the end
4750 with zeros if necessary. SIZE must always be specified. The returned
4751 value is the actual number of bytes of assembler data generated, which
4752 may be bigger than SIZE if the object contains a variable length field.
4754 SIZE is important for structure constructors,
4755 since trailing members may have been omitted from the constructor.
4756 It is also important for initialization of arrays from string constants
4757 since the full length of the string constant might not be wanted.
4758 It is also needed for initialization of unions, where the initializer's
4759 type is just one member, and that may not be as long as the union.
4761 There a case in which we would fail to output exactly SIZE bytes:
4762 for a structure constructor that wants to produce more than SIZE bytes.
4763 But such constructors will never be generated for any possible input.
4765 ALIGN is the alignment of the data in bits.
4767 If REVERSE is true, EXP is output in reverse storage order. */
4769 static unsigned HOST_WIDE_INT
4770 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align,
4771 bool reverse)
4773 enum tree_code code;
4774 unsigned HOST_WIDE_INT thissize;
4775 rtx cst;
4777 if (size == 0 || flag_syntax_only)
4778 return size;
4780 /* See if we're trying to initialize a pointer in a non-default mode
4781 to the address of some declaration somewhere. If the target says
4782 the mode is valid for pointers, assume the target has a way of
4783 resolving it. */
4784 if (TREE_CODE (exp) == NOP_EXPR
4785 && POINTER_TYPE_P (TREE_TYPE (exp))
4786 && targetm.addr_space.valid_pointer_mode
4787 (SCALAR_INT_TYPE_MODE (TREE_TYPE (exp)),
4788 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4790 tree saved_type = TREE_TYPE (exp);
4792 /* Peel off any intermediate conversions-to-pointer for valid
4793 pointer modes. */
4794 while (TREE_CODE (exp) == NOP_EXPR
4795 && POINTER_TYPE_P (TREE_TYPE (exp))
4796 && targetm.addr_space.valid_pointer_mode
4797 (SCALAR_INT_TYPE_MODE (TREE_TYPE (exp)),
4798 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4799 exp = TREE_OPERAND (exp, 0);
4801 /* If what we're left with is the address of something, we can
4802 convert the address to the final type and output it that
4803 way. */
4804 if (TREE_CODE (exp) == ADDR_EXPR)
4805 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4806 /* Likewise for constant ints. */
4807 else if (TREE_CODE (exp) == INTEGER_CST)
4808 exp = fold_convert (saved_type, exp);
4812 /* Eliminate any conversions since we'll be outputting the underlying
4813 constant. */
4814 while (CONVERT_EXPR_P (exp)
4815 || TREE_CODE (exp) == NON_LVALUE_EXPR
4816 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4818 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4819 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4821 /* Make sure eliminating the conversion is really a no-op, except with
4822 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4823 union types to allow for Ada unchecked unions. */
4824 if (type_size > op_size
4825 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4826 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4827 /* Keep the conversion. */
4828 break;
4829 else
4830 exp = TREE_OPERAND (exp, 0);
4833 code = TREE_CODE (TREE_TYPE (exp));
4834 thissize = int_size_in_bytes (TREE_TYPE (exp));
4836 /* Allow a constructor with no elements for any data type.
4837 This means to fill the space with zeros. */
4838 if (TREE_CODE (exp) == CONSTRUCTOR
4839 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4841 assemble_zeros (size);
4842 return size;
4845 if (TREE_CODE (exp) == FDESC_EXPR)
4847 #ifdef ASM_OUTPUT_FDESC
4848 HOST_WIDE_INT part = tree_to_shwi (TREE_OPERAND (exp, 1));
4849 tree decl = TREE_OPERAND (exp, 0);
4850 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4851 #else
4852 gcc_unreachable ();
4853 #endif
4854 return size;
4857 /* Now output the underlying data. If we've handling the padding, return.
4858 Otherwise, break and ensure SIZE is the size written. */
4859 switch (code)
4861 case BOOLEAN_TYPE:
4862 case INTEGER_TYPE:
4863 case ENUMERAL_TYPE:
4864 case POINTER_TYPE:
4865 case REFERENCE_TYPE:
4866 case OFFSET_TYPE:
4867 case FIXED_POINT_TYPE:
4868 case POINTER_BOUNDS_TYPE:
4869 case NULLPTR_TYPE:
4870 cst = expand_expr (exp, NULL_RTX, VOIDmode, EXPAND_INITIALIZER);
4871 if (reverse)
4872 cst = flip_storage_order (TYPE_MODE (TREE_TYPE (exp)), cst);
4873 if (!assemble_integer (cst, MIN (size, thissize), align, 0))
4874 error ("initializer for integer/fixed-point value is too complicated");
4875 break;
4877 case REAL_TYPE:
4878 if (TREE_CODE (exp) != REAL_CST)
4879 error ("initializer for floating value is not a floating constant");
4880 else
4881 assemble_real (TREE_REAL_CST (exp),
4882 SCALAR_FLOAT_TYPE_MODE (TREE_TYPE (exp)),
4883 align, reverse);
4884 break;
4886 case COMPLEX_TYPE:
4887 output_constant (TREE_REALPART (exp), thissize / 2, align, reverse);
4888 output_constant (TREE_IMAGPART (exp), thissize / 2,
4889 min_align (align, BITS_PER_UNIT * (thissize / 2)),
4890 reverse);
4891 break;
4893 case ARRAY_TYPE:
4894 case VECTOR_TYPE:
4895 switch (TREE_CODE (exp))
4897 case CONSTRUCTOR:
4898 return output_constructor (exp, size, align, reverse, NULL);
4899 case STRING_CST:
4900 thissize
4901 = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4902 assemble_string (TREE_STRING_POINTER (exp), thissize);
4903 break;
4904 case VECTOR_CST:
4906 scalar_mode inner = SCALAR_TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4907 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4908 int elt_size = GET_MODE_SIZE (inner);
4909 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align,
4910 reverse);
4911 thissize = elt_size;
4912 for (unsigned int i = 1; i < VECTOR_CST_NELTS (exp); i++)
4914 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign,
4915 reverse);
4916 thissize += elt_size;
4918 break;
4920 default:
4921 gcc_unreachable ();
4923 break;
4925 case RECORD_TYPE:
4926 case UNION_TYPE:
4927 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4928 return output_constructor (exp, size, align, reverse, NULL);
4930 case ERROR_MARK:
4931 return 0;
4933 default:
4934 gcc_unreachable ();
4937 if (size > thissize)
4938 assemble_zeros (size - thissize);
4940 return size;
4943 /* Subroutine of output_constructor, used for computing the size of
4944 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4945 type with an unspecified upper bound. */
4947 static unsigned HOST_WIDE_INT
4948 array_size_for_constructor (tree val)
4950 tree max_index;
4951 unsigned HOST_WIDE_INT cnt;
4952 tree index, value, tmp;
4953 offset_int i;
4955 /* This code used to attempt to handle string constants that are not
4956 arrays of single-bytes, but nothing else does, so there's no point in
4957 doing it here. */
4958 if (TREE_CODE (val) == STRING_CST)
4959 return TREE_STRING_LENGTH (val);
4961 max_index = NULL_TREE;
4962 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
4964 if (TREE_CODE (index) == RANGE_EXPR)
4965 index = TREE_OPERAND (index, 1);
4966 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
4967 max_index = index;
4970 if (max_index == NULL_TREE)
4971 return 0;
4973 /* Compute the total number of array elements. */
4974 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
4975 i = wi::to_offset (max_index) - wi::to_offset (tmp) + 1;
4977 /* Multiply by the array element unit size to find number of bytes. */
4978 i *= wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
4980 gcc_assert (wi::fits_uhwi_p (i));
4981 return i.to_uhwi ();
4984 /* Other datastructures + helpers for output_constructor. */
4986 /* output_constructor local state to support interaction with helpers. */
4988 struct oc_local_state {
4990 /* Received arguments. */
4991 tree exp; /* Constructor expression. */
4992 tree type; /* Type of constructor expression. */
4993 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */
4994 unsigned int align; /* Known initial alignment. */
4995 tree min_index; /* Lower bound if specified for an array. */
4997 /* Output processing state. */
4998 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */
4999 int byte; /* Part of a bitfield byte yet to be output. */
5000 int last_relative_index; /* Implicit or explicit index of the last
5001 array element output within a bitfield. */
5002 bool byte_buffer_in_use; /* Whether BYTE is in use. */
5003 bool reverse; /* Whether reverse storage order is in use. */
5005 /* Current element. */
5006 tree field; /* Current field decl in a record. */
5007 tree val; /* Current element value. */
5008 tree index; /* Current element index. */
5012 /* Helper for output_constructor. From the current LOCAL state, output a
5013 RANGE_EXPR element. */
5015 static void
5016 output_constructor_array_range (oc_local_state *local)
5018 unsigned HOST_WIDE_INT fieldsize
5019 = int_size_in_bytes (TREE_TYPE (local->type));
5021 HOST_WIDE_INT lo_index
5022 = tree_to_shwi (TREE_OPERAND (local->index, 0));
5023 HOST_WIDE_INT hi_index
5024 = tree_to_shwi (TREE_OPERAND (local->index, 1));
5025 HOST_WIDE_INT index;
5027 unsigned int align2
5028 = min_align (local->align, fieldsize * BITS_PER_UNIT);
5030 for (index = lo_index; index <= hi_index; index++)
5032 /* Output the element's initial value. */
5033 if (local->val == NULL_TREE)
5034 assemble_zeros (fieldsize);
5035 else
5036 fieldsize
5037 = output_constant (local->val, fieldsize, align2, local->reverse);
5039 /* Count its size. */
5040 local->total_bytes += fieldsize;
5044 /* Helper for output_constructor. From the current LOCAL state, output a
5045 field element that is not true bitfield or part of an outer one. */
5047 static void
5048 output_constructor_regular_field (oc_local_state *local)
5050 /* Field size and position. Since this structure is static, we know the
5051 positions are constant. */
5052 unsigned HOST_WIDE_INT fieldsize;
5053 HOST_WIDE_INT fieldpos;
5055 unsigned int align2;
5057 /* Output any buffered-up bit-fields preceding this element. */
5058 if (local->byte_buffer_in_use)
5060 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5061 local->total_bytes++;
5062 local->byte_buffer_in_use = false;
5065 if (local->index != NULL_TREE)
5067 /* Perform the index calculation in modulo arithmetic but
5068 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
5069 but we are using an unsigned sizetype. */
5070 unsigned prec = TYPE_PRECISION (sizetype);
5071 offset_int idx = wi::sext (wi::to_offset (local->index)
5072 - wi::to_offset (local->min_index), prec);
5073 fieldpos = (idx * wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (local->val))))
5074 .to_short_addr ();
5076 else if (local->field != NULL_TREE)
5077 fieldpos = int_byte_position (local->field);
5078 else
5079 fieldpos = 0;
5081 /* Advance to offset of this element.
5082 Note no alignment needed in an array, since that is guaranteed
5083 if each element has the proper size. */
5084 if (local->field != NULL_TREE || local->index != NULL_TREE)
5086 if (fieldpos > local->total_bytes)
5088 assemble_zeros (fieldpos - local->total_bytes);
5089 local->total_bytes = fieldpos;
5091 else
5092 /* Must not go backwards. */
5093 gcc_assert (fieldpos == local->total_bytes);
5096 /* Find the alignment of this element. */
5097 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
5099 /* Determine size this element should occupy. */
5100 if (local->field)
5102 fieldsize = 0;
5104 /* If this is an array with an unspecified upper bound,
5105 the initializer determines the size. */
5106 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
5107 but we cannot do this until the deprecated support for
5108 initializing zero-length array members is removed. */
5109 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
5110 && (!TYPE_DOMAIN (TREE_TYPE (local->field))
5111 || !TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field)))))
5113 fieldsize = array_size_for_constructor (local->val);
5114 /* Given a non-empty initialization, this field had better
5115 be last. Given a flexible array member, the next field
5116 on the chain is a TYPE_DECL of the enclosing struct. */
5117 const_tree next = DECL_CHAIN (local->field);
5118 gcc_assert (!fieldsize || !next || TREE_CODE (next) != FIELD_DECL);
5120 else
5121 fieldsize = tree_to_uhwi (DECL_SIZE_UNIT (local->field));
5123 else
5124 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
5126 /* Output the element's initial value. */
5127 if (local->val == NULL_TREE)
5128 assemble_zeros (fieldsize);
5129 else
5130 fieldsize
5131 = output_constant (local->val, fieldsize, align2, local->reverse);
5133 /* Count its size. */
5134 local->total_bytes += fieldsize;
5137 /* Helper for output_constructor. From the LOCAL state, output an element
5138 that is a true bitfield or part of an outer one. BIT_OFFSET is the offset
5139 from the start of a possibly ongoing outer byte buffer. */
5141 static void
5142 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
5144 /* Bit size of this element. */
5145 HOST_WIDE_INT ebitsize
5146 = (local->field
5147 ? tree_to_uhwi (DECL_SIZE (local->field))
5148 : tree_to_uhwi (TYPE_SIZE (TREE_TYPE (local->type))));
5150 /* Relative index of this element if this is an array component. */
5151 HOST_WIDE_INT relative_index
5152 = (!local->field
5153 ? (local->index
5154 ? (tree_to_shwi (local->index)
5155 - tree_to_shwi (local->min_index))
5156 : local->last_relative_index + 1)
5157 : 0);
5159 /* Bit position of this element from the start of the containing
5160 constructor. */
5161 HOST_WIDE_INT constructor_relative_ebitpos
5162 = (local->field
5163 ? int_bit_position (local->field)
5164 : ebitsize * relative_index);
5166 /* Bit position of this element from the start of a possibly ongoing
5167 outer byte buffer. */
5168 HOST_WIDE_INT byte_relative_ebitpos
5169 = bit_offset + constructor_relative_ebitpos;
5171 /* From the start of a possibly ongoing outer byte buffer, offsets to
5172 the first bit of this element and to the first bit past the end of
5173 this element. */
5174 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
5175 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
5177 local->last_relative_index = relative_index;
5179 if (local->val == NULL_TREE)
5180 local->val = integer_zero_node;
5182 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
5183 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
5184 local->val = TREE_OPERAND (local->val, 0);
5186 if (TREE_CODE (local->val) != INTEGER_CST
5187 && TREE_CODE (local->val) != CONSTRUCTOR)
5189 error ("invalid initial value for member %qE", DECL_NAME (local->field));
5190 return;
5193 /* If this field does not start in this (or next) byte, skip some bytes. */
5194 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5196 /* Output remnant of any bit field in previous bytes. */
5197 if (local->byte_buffer_in_use)
5199 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5200 local->total_bytes++;
5201 local->byte_buffer_in_use = false;
5204 /* If still not at proper byte, advance to there. */
5205 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5207 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
5208 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
5209 local->total_bytes = next_offset / BITS_PER_UNIT;
5213 /* Set up the buffer if necessary. */
5214 if (!local->byte_buffer_in_use)
5216 local->byte = 0;
5217 if (ebitsize > 0)
5218 local->byte_buffer_in_use = true;
5221 /* If this is nested constructor, recurse passing the bit offset and the
5222 pending data, then retrieve the new pending data afterwards. */
5223 if (TREE_CODE (local->val) == CONSTRUCTOR)
5225 oc_outer_state temp_state;
5226 temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5227 temp_state.byte = local->byte;
5228 local->total_bytes
5229 += output_constructor (local->val, 0, 0, local->reverse, &temp_state);
5230 local->byte = temp_state.byte;
5231 return;
5234 /* Otherwise, we must split the element into pieces that fall within
5235 separate bytes, and combine each byte with previous or following
5236 bit-fields. */
5237 while (next_offset < end_offset)
5239 int this_time;
5240 int shift;
5241 HOST_WIDE_INT value;
5242 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5243 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5245 /* Advance from byte to byte within this element when necessary. */
5246 while (next_byte != local->total_bytes)
5248 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5249 local->total_bytes++;
5250 local->byte = 0;
5253 /* Number of bits we can process at once (all part of the same byte). */
5254 this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5255 if (local->reverse ? !BYTES_BIG_ENDIAN : BYTES_BIG_ENDIAN)
5257 /* For big-endian data, take the most significant bits (of the
5258 bits that are significant) first and put them into bytes from
5259 the most significant end. */
5260 shift = end_offset - next_offset - this_time;
5262 /* Don't try to take a bunch of bits that cross
5263 the word boundary in the INTEGER_CST. We can
5264 only select bits from one element. */
5265 if ((shift / HOST_BITS_PER_WIDE_INT)
5266 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5268 const int end = shift + this_time - 1;
5269 shift = end & -HOST_BITS_PER_WIDE_INT;
5270 this_time = end - shift + 1;
5273 /* Now get the bits from the appropriate constant word. */
5274 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5275 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5277 /* Get the result. This works only when:
5278 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5279 local->byte |= (((value >> shift)
5280 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5281 << (BITS_PER_UNIT - this_time - next_bit));
5283 else
5285 /* On little-endian machines, take the least significant bits of
5286 the value first and pack them starting at the least significant
5287 bits of the bytes. */
5288 shift = next_offset - byte_relative_ebitpos;
5290 /* Don't try to take a bunch of bits that cross
5291 the word boundary in the INTEGER_CST. We can
5292 only select bits from one element. */
5293 if ((shift / HOST_BITS_PER_WIDE_INT)
5294 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5295 this_time
5296 = HOST_BITS_PER_WIDE_INT - (shift & (HOST_BITS_PER_WIDE_INT - 1));
5298 /* Now get the bits from the appropriate constant word. */
5299 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5300 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5302 /* Get the result. This works only when:
5303 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5304 local->byte |= (((value >> shift)
5305 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5306 << next_bit);
5309 next_offset += this_time;
5310 local->byte_buffer_in_use = true;
5314 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5315 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5316 caller output state of relevance in recursive invocations. */
5318 static unsigned HOST_WIDE_INT
5319 output_constructor (tree exp, unsigned HOST_WIDE_INT size, unsigned int align,
5320 bool reverse, oc_outer_state *outer)
5322 unsigned HOST_WIDE_INT cnt;
5323 constructor_elt *ce;
5324 oc_local_state local;
5326 /* Setup our local state to communicate with helpers. */
5327 local.exp = exp;
5328 local.type = TREE_TYPE (exp);
5329 local.size = size;
5330 local.align = align;
5331 if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5332 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5333 else
5334 local.min_index = integer_zero_node;
5336 local.total_bytes = 0;
5337 local.byte_buffer_in_use = outer != NULL;
5338 local.byte = outer ? outer->byte : 0;
5339 local.last_relative_index = -1;
5340 /* The storage order is specified for every aggregate type. */
5341 if (AGGREGATE_TYPE_P (local.type))
5342 local.reverse = TYPE_REVERSE_STORAGE_ORDER (local.type);
5343 else
5344 local.reverse = reverse;
5346 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5348 /* As CE goes through the elements of the constant, FIELD goes through the
5349 structure fields if the constant is a structure. If the constant is a
5350 union, we override this by getting the field from the TREE_LIST element.
5351 But the constant could also be an array. Then FIELD is zero.
5353 There is always a maximum of one element in the chain LINK for unions
5354 (even if the initializer in a source program incorrectly contains
5355 more one). */
5357 if (TREE_CODE (local.type) == RECORD_TYPE)
5358 local.field = TYPE_FIELDS (local.type);
5359 else
5360 local.field = NULL_TREE;
5362 for (cnt = 0;
5363 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5364 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5366 local.val = ce->value;
5367 local.index = NULL_TREE;
5369 /* The element in a union constructor specifies the proper field
5370 or index. */
5371 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5372 local.field = ce->index;
5374 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5375 local.index = ce->index;
5377 if (local.field && flag_verbose_asm)
5378 fprintf (asm_out_file, "%s %s:\n",
5379 ASM_COMMENT_START,
5380 DECL_NAME (local.field)
5381 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5382 : "<anonymous>");
5384 /* Eliminate the marker that makes a cast not be an lvalue. */
5385 if (local.val != NULL_TREE)
5386 STRIP_NOPS (local.val);
5388 /* Output the current element, using the appropriate helper ... */
5390 /* For an array slice not part of an outer bitfield. */
5391 if (!outer
5392 && local.index != NULL_TREE
5393 && TREE_CODE (local.index) == RANGE_EXPR)
5394 output_constructor_array_range (&local);
5396 /* For a field that is neither a true bitfield nor part of an outer one,
5397 known to be at least byte aligned and multiple-of-bytes long. */
5398 else if (!outer
5399 && (local.field == NULL_TREE
5400 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5401 output_constructor_regular_field (&local);
5403 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5404 supported for scalar fields, so we may need to convert first. */
5405 else
5407 if (TREE_CODE (local.val) == REAL_CST)
5408 local.val
5409 = fold_unary (VIEW_CONVERT_EXPR,
5410 build_nonstandard_integer_type
5411 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5412 local.val);
5413 output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5417 /* If we are not at toplevel, save the pending data for our caller.
5418 Otherwise output the pending data and padding zeros as needed. */
5419 if (outer)
5420 outer->byte = local.byte;
5421 else
5423 if (local.byte_buffer_in_use)
5425 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5426 local.total_bytes++;
5429 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5431 assemble_zeros (local.size - local.total_bytes);
5432 local.total_bytes = local.size;
5436 return local.total_bytes;
5439 /* Mark DECL as weak. */
5441 static void
5442 mark_weak (tree decl)
5444 if (DECL_WEAK (decl))
5445 return;
5447 struct symtab_node *n = symtab_node::get (decl);
5448 if (n && n->refuse_visibility_changes)
5449 error ("%+qD declared weak after being used", decl);
5450 DECL_WEAK (decl) = 1;
5452 if (DECL_RTL_SET_P (decl)
5453 && MEM_P (DECL_RTL (decl))
5454 && XEXP (DECL_RTL (decl), 0)
5455 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5456 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5459 /* Merge weak status between NEWDECL and OLDDECL. */
5461 void
5462 merge_weak (tree newdecl, tree olddecl)
5464 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5466 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5468 tree *pwd;
5469 /* We put the NEWDECL on the weak_decls list at some point
5470 and OLDDECL as well. Keep just OLDDECL on the list. */
5471 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5472 if (TREE_VALUE (*pwd) == newdecl)
5474 *pwd = TREE_CHAIN (*pwd);
5475 break;
5478 return;
5481 if (DECL_WEAK (newdecl))
5483 tree wd;
5485 /* NEWDECL is weak, but OLDDECL is not. */
5487 /* If we already output the OLDDECL, we're in trouble; we can't
5488 go back and make it weak. This should never happen in
5489 unit-at-a-time compilation. */
5490 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5492 /* If we've already generated rtl referencing OLDDECL, we may
5493 have done so in a way that will not function properly with
5494 a weak symbol. Again in unit-at-a-time this should be
5495 impossible. */
5496 gcc_assert (!TREE_USED (olddecl)
5497 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5499 /* PR 49899: You cannot convert a static function into a weak, public function. */
5500 if (! TREE_PUBLIC (olddecl) && TREE_PUBLIC (newdecl))
5501 error ("weak declaration of %q+D being applied to a already "
5502 "existing, static definition", newdecl);
5504 if (TARGET_SUPPORTS_WEAK)
5506 /* We put the NEWDECL on the weak_decls list at some point.
5507 Replace it with the OLDDECL. */
5508 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5509 if (TREE_VALUE (wd) == newdecl)
5511 TREE_VALUE (wd) = olddecl;
5512 break;
5514 /* We may not find the entry on the list. If NEWDECL is a
5515 weak alias, then we will have already called
5516 globalize_decl to remove the entry; in that case, we do
5517 not need to do anything. */
5520 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5521 mark_weak (olddecl);
5523 else
5524 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5525 weak. Just update NEWDECL to indicate that it's weak too. */
5526 mark_weak (newdecl);
5529 /* Declare DECL to be a weak symbol. */
5531 void
5532 declare_weak (tree decl)
5534 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5535 if (! TREE_PUBLIC (decl))
5537 error ("weak declaration of %q+D must be public", decl);
5538 return;
5540 else if (!TARGET_SUPPORTS_WEAK)
5541 warning (0, "weak declaration of %q+D not supported", decl);
5543 mark_weak (decl);
5544 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5545 DECL_ATTRIBUTES (decl)
5546 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5549 static void
5550 weak_finish_1 (tree decl)
5552 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5553 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5554 #endif
5556 if (! TREE_USED (decl))
5557 return;
5559 #ifdef ASM_WEAKEN_DECL
5560 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5561 #else
5562 #ifdef ASM_WEAKEN_LABEL
5563 ASM_WEAKEN_LABEL (asm_out_file, name);
5564 #else
5565 #ifdef ASM_OUTPUT_WEAK_ALIAS
5567 static bool warn_once = 0;
5568 if (! warn_once)
5570 warning (0, "only weak aliases are supported in this configuration");
5571 warn_once = 1;
5573 return;
5575 #endif
5576 #endif
5577 #endif
5580 /* Fiven an assembly name, find the decl it is associated with. */
5581 static tree
5582 find_decl (tree target)
5584 symtab_node *node = symtab_node::get_for_asmname (target);
5585 if (node)
5586 return node->decl;
5587 return NULL_TREE;
5590 /* This TREE_LIST contains weakref targets. */
5592 static GTY(()) tree weakref_targets;
5594 /* Emit any pending weak declarations. */
5596 void
5597 weak_finish (void)
5599 tree t;
5601 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5603 tree alias_decl = TREE_PURPOSE (t);
5604 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5606 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5607 /* Remove alias_decl from the weak list, but leave entries for
5608 the target alone. */
5609 target = NULL_TREE;
5610 #ifndef ASM_OUTPUT_WEAKREF
5611 else if (! TREE_SYMBOL_REFERENCED (target))
5613 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5614 defined, otherwise we and weak_finish_1 would use
5615 different macros. */
5616 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5617 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5618 # else
5619 tree decl = find_decl (target);
5621 if (! decl)
5623 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5624 TREE_CODE (alias_decl), target,
5625 TREE_TYPE (alias_decl));
5627 DECL_EXTERNAL (decl) = 1;
5628 TREE_PUBLIC (decl) = 1;
5629 DECL_ARTIFICIAL (decl) = 1;
5630 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5631 TREE_USED (decl) = 1;
5634 weak_finish_1 (decl);
5635 # endif
5637 #endif
5640 tree *p;
5641 tree t2;
5643 /* Remove the alias and the target from the pending weak list
5644 so that we do not emit any .weak directives for the former,
5645 nor multiple .weak directives for the latter. */
5646 for (p = &weak_decls; (t2 = *p) ; )
5648 if (TREE_VALUE (t2) == alias_decl
5649 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5650 *p = TREE_CHAIN (t2);
5651 else
5652 p = &TREE_CHAIN (t2);
5655 /* Remove other weakrefs to the same target, to speed things up. */
5656 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5658 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5659 *p = TREE_CHAIN (t2);
5660 else
5661 p = &TREE_CHAIN (t2);
5666 for (t = weak_decls; t; t = TREE_CHAIN (t))
5668 tree decl = TREE_VALUE (t);
5670 weak_finish_1 (decl);
5674 /* Emit the assembly bits to indicate that DECL is globally visible. */
5676 static void
5677 globalize_decl (tree decl)
5680 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5681 if (DECL_WEAK (decl))
5683 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5684 tree *p, t;
5686 #ifdef ASM_WEAKEN_DECL
5687 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5688 #else
5689 ASM_WEAKEN_LABEL (asm_out_file, name);
5690 #endif
5692 /* Remove this function from the pending weak list so that
5693 we do not emit multiple .weak directives for it. */
5694 for (p = &weak_decls; (t = *p) ; )
5696 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5697 *p = TREE_CHAIN (t);
5698 else
5699 p = &TREE_CHAIN (t);
5702 /* Remove weakrefs to the same target from the pending weakref
5703 list, for the same reason. */
5704 for (p = &weakref_targets; (t = *p) ; )
5706 if (DECL_ASSEMBLER_NAME (decl)
5707 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5708 *p = TREE_CHAIN (t);
5709 else
5710 p = &TREE_CHAIN (t);
5713 return;
5715 #endif
5717 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5720 vec<alias_pair, va_gc> *alias_pairs;
5722 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5723 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5724 tree node is DECL to have the value of the tree node TARGET. */
5726 void
5727 do_assemble_alias (tree decl, tree target)
5729 tree id;
5731 /* Emulated TLS had better not get this var. */
5732 gcc_assert (!(!targetm.have_tls
5733 && VAR_P (decl)
5734 && DECL_THREAD_LOCAL_P (decl)));
5736 if (TREE_ASM_WRITTEN (decl))
5737 return;
5739 id = DECL_ASSEMBLER_NAME (decl);
5740 ultimate_transparent_alias_target (&id);
5741 ultimate_transparent_alias_target (&target);
5743 /* We must force creation of DECL_RTL for debug info generation, even though
5744 we don't use it here. */
5745 make_decl_rtl (decl);
5747 TREE_ASM_WRITTEN (decl) = 1;
5748 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5749 TREE_ASM_WRITTEN (id) = 1;
5751 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5753 if (!TREE_SYMBOL_REFERENCED (target))
5754 weakref_targets = tree_cons (decl, target, weakref_targets);
5756 #ifdef ASM_OUTPUT_WEAKREF
5757 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5758 IDENTIFIER_POINTER (id),
5759 IDENTIFIER_POINTER (target));
5760 #else
5761 if (!TARGET_SUPPORTS_WEAK)
5763 error_at (DECL_SOURCE_LOCATION (decl),
5764 "weakref is not supported in this configuration");
5765 return;
5767 #endif
5768 return;
5771 #ifdef ASM_OUTPUT_DEF
5772 tree orig_decl = decl;
5774 if (TREE_CODE (decl) == FUNCTION_DECL
5775 && cgraph_node::get (decl)->instrumentation_clone
5776 && cgraph_node::get (decl)->instrumented_version)
5777 orig_decl = cgraph_node::get (decl)->instrumented_version->decl;
5779 /* Make name accessible from other files, if appropriate. */
5781 if (TREE_PUBLIC (decl) || TREE_PUBLIC (orig_decl))
5783 globalize_decl (decl);
5784 maybe_assemble_visibility (decl);
5786 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5788 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5789 if (targetm.has_ifunc_p ())
5790 ASM_OUTPUT_TYPE_DIRECTIVE
5791 (asm_out_file, IDENTIFIER_POINTER (id),
5792 IFUNC_ASM_TYPE);
5793 else
5794 #endif
5795 error_at (DECL_SOURCE_LOCATION (decl),
5796 "ifunc is not supported on this target");
5799 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5800 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5801 # else
5802 ASM_OUTPUT_DEF (asm_out_file,
5803 IDENTIFIER_POINTER (id),
5804 IDENTIFIER_POINTER (target));
5805 # endif
5806 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5808 const char *name;
5809 tree *p, t;
5811 name = IDENTIFIER_POINTER (id);
5812 # ifdef ASM_WEAKEN_DECL
5813 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5814 # else
5815 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5816 # endif
5817 /* Remove this function from the pending weak list so that
5818 we do not emit multiple .weak directives for it. */
5819 for (p = &weak_decls; (t = *p) ; )
5820 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t))
5821 || id == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5822 *p = TREE_CHAIN (t);
5823 else
5824 p = &TREE_CHAIN (t);
5826 /* Remove weakrefs to the same target from the pending weakref
5827 list, for the same reason. */
5828 for (p = &weakref_targets; (t = *p) ; )
5830 if (id == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5831 *p = TREE_CHAIN (t);
5832 else
5833 p = &TREE_CHAIN (t);
5836 #endif
5839 /* Emit an assembler directive to make the symbol for DECL an alias to
5840 the symbol for TARGET. */
5842 void
5843 assemble_alias (tree decl, tree target)
5845 tree target_decl;
5847 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5849 tree alias = DECL_ASSEMBLER_NAME (decl);
5851 ultimate_transparent_alias_target (&target);
5853 if (alias == target)
5854 error ("weakref %q+D ultimately targets itself", decl);
5855 if (TREE_PUBLIC (decl))
5856 error ("weakref %q+D must have static linkage", decl);
5858 else
5860 #if !defined (ASM_OUTPUT_DEF)
5861 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5862 error_at (DECL_SOURCE_LOCATION (decl),
5863 "alias definitions not supported in this configuration");
5864 TREE_ASM_WRITTEN (decl) = 1;
5865 return;
5866 # else
5867 if (!DECL_WEAK (decl))
5869 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5870 error_at (DECL_SOURCE_LOCATION (decl),
5871 "ifunc is not supported in this configuration");
5872 else
5873 error_at (DECL_SOURCE_LOCATION (decl),
5874 "only weak aliases are supported in this configuration");
5875 TREE_ASM_WRITTEN (decl) = 1;
5876 return;
5878 # endif
5879 #endif
5881 TREE_USED (decl) = 1;
5883 /* Allow aliases to aliases. */
5884 if (TREE_CODE (decl) == FUNCTION_DECL)
5885 cgraph_node::get_create (decl)->alias = true;
5886 else
5887 varpool_node::get_create (decl)->alias = true;
5889 /* If the target has already been emitted, we don't have to queue the
5890 alias. This saves a tad of memory. */
5891 if (symtab->global_info_ready)
5892 target_decl = find_decl (target);
5893 else
5894 target_decl= NULL;
5895 if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5896 || symtab->state >= EXPANSION)
5897 do_assemble_alias (decl, target);
5898 else
5900 alias_pair p = {decl, target};
5901 vec_safe_push (alias_pairs, p);
5905 /* Record and output a table of translations from original function
5906 to its transaction aware clone. Note that tm_pure functions are
5907 considered to be their own clone. */
5909 struct tm_clone_hasher : ggc_cache_ptr_hash<tree_map>
5911 static hashval_t hash (tree_map *m) { return tree_map_hash (m); }
5912 static bool equal (tree_map *a, tree_map *b) { return tree_map_eq (a, b); }
5914 static int
5915 keep_cache_entry (tree_map *&e)
5917 return ggc_marked_p (e->base.from);
5921 static GTY((cache)) hash_table<tm_clone_hasher> *tm_clone_hash;
5923 void
5924 record_tm_clone_pair (tree o, tree n)
5926 struct tree_map **slot, *h;
5928 if (tm_clone_hash == NULL)
5929 tm_clone_hash = hash_table<tm_clone_hasher>::create_ggc (32);
5931 h = ggc_alloc<tree_map> ();
5932 h->hash = htab_hash_pointer (o);
5933 h->base.from = o;
5934 h->to = n;
5936 slot = tm_clone_hash->find_slot_with_hash (h, h->hash, INSERT);
5937 *slot = h;
5940 tree
5941 get_tm_clone_pair (tree o)
5943 if (tm_clone_hash)
5945 struct tree_map *h, in;
5947 in.base.from = o;
5948 in.hash = htab_hash_pointer (o);
5949 h = tm_clone_hash->find_with_hash (&in, in.hash);
5950 if (h)
5951 return h->to;
5953 return NULL_TREE;
5956 struct tm_alias_pair
5958 unsigned int uid;
5959 tree from;
5960 tree to;
5964 /* Dump the actual pairs to the .tm_clone_table section. */
5966 static void
5967 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
5969 unsigned i;
5970 tm_alias_pair *p;
5971 bool switched = false;
5973 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
5975 tree src = p->from;
5976 tree dst = p->to;
5977 struct cgraph_node *src_n = cgraph_node::get (src);
5978 struct cgraph_node *dst_n = cgraph_node::get (dst);
5980 /* The function ipa_tm_create_version() marks the clone as needed if
5981 the original function was needed. But we also mark the clone as
5982 needed if we ever called the clone indirectly through
5983 TM_GETTMCLONE. If neither of these are true, we didn't generate
5984 a clone, and we didn't call it indirectly... no sense keeping it
5985 in the clone table. */
5986 if (!dst_n || !dst_n->definition)
5987 continue;
5989 /* This covers the case where we have optimized the original
5990 function away, and only access the transactional clone. */
5991 if (!src_n || !src_n->definition)
5992 continue;
5994 if (!switched)
5996 switch_to_section (targetm.asm_out.tm_clone_table_section ());
5997 assemble_align (POINTER_SIZE);
5998 switched = true;
6001 assemble_integer (XEXP (DECL_RTL (src), 0),
6002 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
6003 assemble_integer (XEXP (DECL_RTL (dst), 0),
6004 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
6008 /* Provide a default for the tm_clone_table section. */
6010 section *
6011 default_clone_table_section (void)
6013 return get_named_section (NULL, ".tm_clone_table", 3);
6016 /* Helper comparison function for qsorting by the DECL_UID stored in
6017 alias_pair->emitted_diags. */
6019 static int
6020 tm_alias_pair_cmp (const void *x, const void *y)
6022 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
6023 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
6024 if (p1->uid < p2->uid)
6025 return -1;
6026 if (p1->uid > p2->uid)
6027 return 1;
6028 return 0;
6031 void
6032 finish_tm_clone_pairs (void)
6034 vec<tm_alias_pair> tm_alias_pairs = vNULL;
6036 if (tm_clone_hash == NULL)
6037 return;
6039 /* We need a determenistic order for the .tm_clone_table, otherwise
6040 we will get bootstrap comparison failures, so dump the hash table
6041 to a vector, sort it, and dump the vector. */
6043 /* Dump the hashtable to a vector. */
6044 tree_map *map;
6045 hash_table<tm_clone_hasher>::iterator iter;
6046 FOR_EACH_HASH_TABLE_ELEMENT (*tm_clone_hash, map, tree_map *, iter)
6048 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
6049 tm_alias_pairs.safe_push (p);
6051 /* Sort it. */
6052 tm_alias_pairs.qsort (tm_alias_pair_cmp);
6054 /* Dump it. */
6055 dump_tm_clone_pairs (tm_alias_pairs);
6057 tm_clone_hash->empty ();
6058 tm_clone_hash = NULL;
6059 tm_alias_pairs.release ();
6063 /* Emit an assembler directive to set symbol for DECL visibility to
6064 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
6066 void
6067 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
6068 int vis ATTRIBUTE_UNUSED)
6070 #ifdef HAVE_GAS_HIDDEN
6071 static const char * const visibility_types[] = {
6072 NULL, "protected", "hidden", "internal"
6075 const char *name, *type;
6076 tree id;
6078 id = DECL_ASSEMBLER_NAME (decl);
6079 ultimate_transparent_alias_target (&id);
6080 name = IDENTIFIER_POINTER (id);
6082 type = visibility_types[vis];
6084 fprintf (asm_out_file, "\t.%s\t", type);
6085 assemble_name (asm_out_file, name);
6086 fprintf (asm_out_file, "\n");
6087 #else
6088 if (!DECL_ARTIFICIAL (decl))
6089 warning (OPT_Wattributes, "visibility attribute not supported "
6090 "in this configuration; ignored");
6091 #endif
6094 /* A helper function to call assemble_visibility when needed for a decl. */
6097 maybe_assemble_visibility (tree decl)
6099 enum symbol_visibility vis = DECL_VISIBILITY (decl);
6101 if (TREE_CODE (decl) == FUNCTION_DECL
6102 && cgraph_node::get (decl)
6103 && cgraph_node::get (decl)->instrumentation_clone
6104 && cgraph_node::get (decl)->instrumented_version)
6105 vis = DECL_VISIBILITY (cgraph_node::get (decl)->instrumented_version->decl);
6107 if (vis != VISIBILITY_DEFAULT)
6109 targetm.asm_out.assemble_visibility (decl, vis);
6110 return 1;
6112 else
6113 return 0;
6116 /* Returns 1 if the target configuration supports defining public symbols
6117 so that one of them will be chosen at link time instead of generating a
6118 multiply-defined symbol error, whether through the use of weak symbols or
6119 a target-specific mechanism for having duplicates discarded. */
6122 supports_one_only (void)
6124 if (SUPPORTS_ONE_ONLY)
6125 return 1;
6126 return TARGET_SUPPORTS_WEAK;
6129 /* Set up DECL as a public symbol that can be defined in multiple
6130 translation units without generating a linker error. */
6132 void
6133 make_decl_one_only (tree decl, tree comdat_group)
6135 struct symtab_node *symbol;
6136 gcc_assert (VAR_OR_FUNCTION_DECL_P (decl));
6138 TREE_PUBLIC (decl) = 1;
6140 if (VAR_P (decl))
6141 symbol = varpool_node::get_create (decl);
6142 else
6143 symbol = cgraph_node::get_create (decl);
6145 if (SUPPORTS_ONE_ONLY)
6147 #ifdef MAKE_DECL_ONE_ONLY
6148 MAKE_DECL_ONE_ONLY (decl);
6149 #endif
6150 symbol->set_comdat_group (comdat_group);
6152 else if (VAR_P (decl)
6153 && (DECL_INITIAL (decl) == 0
6154 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
6155 DECL_COMMON (decl) = 1;
6156 else
6158 gcc_assert (TARGET_SUPPORTS_WEAK);
6159 DECL_WEAK (decl) = 1;
6163 void
6164 init_varasm_once (void)
6166 section_htab = hash_table<section_hasher>::create_ggc (31);
6167 object_block_htab = hash_table<object_block_hasher>::create_ggc (31);
6168 const_desc_htab = hash_table<tree_descriptor_hasher>::create_ggc (1009);
6170 shared_constant_pool = create_constant_pool ();
6172 #ifdef TEXT_SECTION_ASM_OP
6173 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
6174 TEXT_SECTION_ASM_OP);
6175 #endif
6177 #ifdef DATA_SECTION_ASM_OP
6178 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
6179 DATA_SECTION_ASM_OP);
6180 #endif
6182 #ifdef SDATA_SECTION_ASM_OP
6183 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
6184 SDATA_SECTION_ASM_OP);
6185 #endif
6187 #ifdef READONLY_DATA_SECTION_ASM_OP
6188 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
6189 READONLY_DATA_SECTION_ASM_OP);
6190 #endif
6192 #ifdef CTORS_SECTION_ASM_OP
6193 ctors_section = get_unnamed_section (0, output_section_asm_op,
6194 CTORS_SECTION_ASM_OP);
6195 #endif
6197 #ifdef DTORS_SECTION_ASM_OP
6198 dtors_section = get_unnamed_section (0, output_section_asm_op,
6199 DTORS_SECTION_ASM_OP);
6200 #endif
6202 #ifdef BSS_SECTION_ASM_OP
6203 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6204 output_section_asm_op,
6205 BSS_SECTION_ASM_OP);
6206 #endif
6208 #ifdef SBSS_SECTION_ASM_OP
6209 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6210 output_section_asm_op,
6211 SBSS_SECTION_ASM_OP);
6212 #endif
6214 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6215 | SECTION_COMMON, emit_tls_common);
6216 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6217 | SECTION_COMMON, emit_local);
6218 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6219 | SECTION_COMMON, emit_common);
6221 #if defined ASM_OUTPUT_ALIGNED_BSS
6222 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
6223 emit_bss);
6224 #endif
6226 targetm.asm_out.init_sections ();
6228 if (readonly_data_section == NULL)
6229 readonly_data_section = text_section;
6231 #ifdef ASM_OUTPUT_EXTERNAL
6232 pending_assemble_externals_set = new hash_set<tree>;
6233 #endif
6236 enum tls_model
6237 decl_default_tls_model (const_tree decl)
6239 enum tls_model kind;
6240 bool is_local;
6242 is_local = targetm.binds_local_p (decl);
6243 if (!flag_shlib)
6245 if (is_local)
6246 kind = TLS_MODEL_LOCAL_EXEC;
6247 else
6248 kind = TLS_MODEL_INITIAL_EXEC;
6251 /* Local dynamic is inefficient when we're not combining the
6252 parts of the address. */
6253 else if (optimize && is_local)
6254 kind = TLS_MODEL_LOCAL_DYNAMIC;
6255 else
6256 kind = TLS_MODEL_GLOBAL_DYNAMIC;
6257 if (kind < flag_tls_default)
6258 kind = flag_tls_default;
6260 return kind;
6263 /* Select a set of attributes for section NAME based on the properties
6264 of DECL and whether or not RELOC indicates that DECL's initializer
6265 might contain runtime relocations.
6267 We make the section read-only and executable for a function decl,
6268 read-only for a const data decl, and writable for a non-const data decl. */
6270 unsigned int
6271 default_section_type_flags (tree decl, const char *name, int reloc)
6273 unsigned int flags;
6275 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6276 flags = SECTION_CODE;
6277 else if (decl)
6279 enum section_category category
6280 = categorize_decl_for_section (decl, reloc);
6281 if (decl_readonly_section_1 (category))
6282 flags = 0;
6283 else if (category == SECCAT_DATA_REL_RO
6284 || category == SECCAT_DATA_REL_RO_LOCAL)
6285 flags = SECTION_WRITE | SECTION_RELRO;
6286 else
6287 flags = SECTION_WRITE;
6289 else
6291 flags = SECTION_WRITE;
6292 if (strcmp (name, ".data.rel.ro") == 0
6293 || strcmp (name, ".data.rel.ro.local") == 0)
6294 flags |= SECTION_RELRO;
6297 if (decl && DECL_P (decl) && DECL_COMDAT_GROUP (decl))
6298 flags |= SECTION_LINKONCE;
6300 if (strcmp (name, ".vtable_map_vars") == 0)
6301 flags |= SECTION_LINKONCE;
6303 if (decl && VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6304 flags |= SECTION_TLS | SECTION_WRITE;
6306 if (strcmp (name, ".bss") == 0
6307 || strncmp (name, ".bss.", 5) == 0
6308 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6309 || strcmp (name, ".persistent.bss") == 0
6310 || strcmp (name, ".sbss") == 0
6311 || strncmp (name, ".sbss.", 6) == 0
6312 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6313 flags |= SECTION_BSS;
6315 if (strcmp (name, ".tdata") == 0
6316 || strncmp (name, ".tdata.", 7) == 0
6317 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6318 flags |= SECTION_TLS;
6320 if (strcmp (name, ".tbss") == 0
6321 || strncmp (name, ".tbss.", 6) == 0
6322 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6323 flags |= SECTION_TLS | SECTION_BSS;
6325 /* These three sections have special ELF types. They are neither
6326 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
6327 want to print a section type (@progbits or @nobits). If someone
6328 is silly enough to emit code or TLS variables to one of these
6329 sections, then don't handle them specially. */
6330 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6331 && (strcmp (name, ".init_array") == 0
6332 || strcmp (name, ".fini_array") == 0
6333 || strcmp (name, ".preinit_array") == 0))
6334 flags |= SECTION_NOTYPE;
6336 return flags;
6339 /* Return true if the target supports some form of global BSS,
6340 either through bss_noswitch_section, or by selecting a BSS
6341 section in TARGET_ASM_SELECT_SECTION. */
6343 bool
6344 have_global_bss_p (void)
6346 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6349 /* Output assembly to switch to section NAME with attribute FLAGS.
6350 Four variants for common object file formats. */
6352 void
6353 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6354 unsigned int flags ATTRIBUTE_UNUSED,
6355 tree decl ATTRIBUTE_UNUSED)
6357 /* Some object formats don't support named sections at all. The
6358 front-end should already have flagged this as an error. */
6359 gcc_unreachable ();
6362 #ifndef TLS_SECTION_ASM_FLAG
6363 #define TLS_SECTION_ASM_FLAG 'T'
6364 #endif
6366 void
6367 default_elf_asm_named_section (const char *name, unsigned int flags,
6368 tree decl)
6370 char flagchars[11], *f = flagchars;
6371 unsigned int numeric_value = 0;
6373 /* If we have already declared this section, we can use an
6374 abbreviated form to switch back to it -- unless this section is
6375 part of a COMDAT groups, in which case GAS requires the full
6376 declaration every time. */
6377 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6378 && (flags & SECTION_DECLARED))
6380 fprintf (asm_out_file, "\t.section\t%s\n", name);
6381 return;
6384 /* If we have a machine specific flag, then use the numeric value to pass
6385 this on to GAS. */
6386 if (targetm.asm_out.elf_flags_numeric (flags, &numeric_value))
6387 snprintf (f, sizeof (flagchars), "0x%08x", numeric_value);
6388 else
6390 if (!(flags & SECTION_DEBUG))
6391 *f++ = 'a';
6392 #if defined (HAVE_GAS_SECTION_EXCLUDE) && HAVE_GAS_SECTION_EXCLUDE == 1
6393 if (flags & SECTION_EXCLUDE)
6394 *f++ = 'e';
6395 #endif
6396 if (flags & SECTION_WRITE)
6397 *f++ = 'w';
6398 if (flags & SECTION_CODE)
6399 *f++ = 'x';
6400 if (flags & SECTION_SMALL)
6401 *f++ = 's';
6402 if (flags & SECTION_MERGE)
6403 *f++ = 'M';
6404 if (flags & SECTION_STRINGS)
6405 *f++ = 'S';
6406 if (flags & SECTION_TLS)
6407 *f++ = TLS_SECTION_ASM_FLAG;
6408 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6409 *f++ = 'G';
6410 #ifdef MACH_DEP_SECTION_ASM_FLAG
6411 if (flags & SECTION_MACH_DEP)
6412 *f++ = MACH_DEP_SECTION_ASM_FLAG;
6413 #endif
6414 *f = '\0';
6417 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6419 if (!(flags & SECTION_NOTYPE))
6421 const char *type;
6422 const char *format;
6424 if (flags & SECTION_BSS)
6425 type = "nobits";
6426 else
6427 type = "progbits";
6429 format = ",@%s";
6430 /* On platforms that use "@" as the assembly comment character,
6431 use "%" instead. */
6432 if (strcmp (ASM_COMMENT_START, "@") == 0)
6433 format = ",%%%s";
6434 fprintf (asm_out_file, format, type);
6436 if (flags & SECTION_ENTSIZE)
6437 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6438 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6440 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6441 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6442 else
6443 fprintf (asm_out_file, ",%s,comdat",
6444 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6448 putc ('\n', asm_out_file);
6451 void
6452 default_coff_asm_named_section (const char *name, unsigned int flags,
6453 tree decl ATTRIBUTE_UNUSED)
6455 char flagchars[8], *f = flagchars;
6457 if (flags & SECTION_WRITE)
6458 *f++ = 'w';
6459 if (flags & SECTION_CODE)
6460 *f++ = 'x';
6461 *f = '\0';
6463 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6466 void
6467 default_pe_asm_named_section (const char *name, unsigned int flags,
6468 tree decl)
6470 default_coff_asm_named_section (name, flags, decl);
6472 if (flags & SECTION_LINKONCE)
6474 /* Functions may have been compiled at various levels of
6475 optimization so we can't use `same_size' here.
6476 Instead, have the linker pick one. */
6477 fprintf (asm_out_file, "\t.linkonce %s\n",
6478 (flags & SECTION_CODE ? "discard" : "same_size"));
6482 /* The lame default section selector. */
6484 section *
6485 default_select_section (tree decl, int reloc,
6486 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6488 if (DECL_P (decl))
6490 if (decl_readonly_section (decl, reloc))
6491 return readonly_data_section;
6493 else if (TREE_CODE (decl) == CONSTRUCTOR)
6495 if (! ((flag_pic && reloc)
6496 || !TREE_READONLY (decl)
6497 || TREE_SIDE_EFFECTS (decl)
6498 || !TREE_CONSTANT (decl)))
6499 return readonly_data_section;
6501 else if (TREE_CODE (decl) == STRING_CST)
6502 return readonly_data_section;
6503 else if (! (flag_pic && reloc))
6504 return readonly_data_section;
6506 return data_section;
6509 enum section_category
6510 categorize_decl_for_section (const_tree decl, int reloc)
6512 enum section_category ret;
6514 if (TREE_CODE (decl) == FUNCTION_DECL)
6515 return SECCAT_TEXT;
6516 else if (TREE_CODE (decl) == STRING_CST)
6518 if ((flag_sanitize & SANITIZE_ADDRESS)
6519 && asan_protect_global (CONST_CAST_TREE (decl)))
6520 /* or !flag_merge_constants */
6521 return SECCAT_RODATA;
6522 else
6523 return SECCAT_RODATA_MERGE_STR;
6525 else if (VAR_P (decl))
6527 if (bss_initializer_p (decl))
6528 ret = SECCAT_BSS;
6529 else if (! TREE_READONLY (decl)
6530 || TREE_SIDE_EFFECTS (decl)
6531 || (DECL_INITIAL (decl)
6532 && ! TREE_CONSTANT (DECL_INITIAL (decl))))
6534 /* Here the reloc_rw_mask is not testing whether the section should
6535 be read-only or not, but whether the dynamic link will have to
6536 do something. If so, we wish to segregate the data in order to
6537 minimize cache misses inside the dynamic linker. */
6538 if (reloc & targetm.asm_out.reloc_rw_mask ())
6539 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6540 else
6541 ret = SECCAT_DATA;
6543 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6544 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6545 else if (reloc || flag_merge_constants < 2
6546 || ((flag_sanitize & SANITIZE_ADDRESS)
6547 && asan_protect_global (CONST_CAST_TREE (decl))))
6548 /* C and C++ don't allow different variables to share the same
6549 location. -fmerge-all-constants allows even that (at the
6550 expense of not conforming). */
6551 ret = SECCAT_RODATA;
6552 else if (DECL_INITIAL (decl)
6553 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6554 ret = SECCAT_RODATA_MERGE_STR_INIT;
6555 else
6556 ret = SECCAT_RODATA_MERGE_CONST;
6558 else if (TREE_CODE (decl) == CONSTRUCTOR)
6560 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6561 || TREE_SIDE_EFFECTS (decl)
6562 || ! TREE_CONSTANT (decl))
6563 ret = SECCAT_DATA;
6564 else
6565 ret = SECCAT_RODATA;
6567 else
6568 ret = SECCAT_RODATA;
6570 /* There are no read-only thread-local sections. */
6571 if (VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6573 /* Note that this would be *just* SECCAT_BSS, except that there's
6574 no concept of a read-only thread-local-data section. */
6575 if (ret == SECCAT_BSS
6576 || DECL_INITIAL (decl) == NULL
6577 || (flag_zero_initialized_in_bss
6578 && initializer_zerop (DECL_INITIAL (decl))))
6579 ret = SECCAT_TBSS;
6580 else
6581 ret = SECCAT_TDATA;
6584 /* If the target uses small data sections, select it. */
6585 else if (targetm.in_small_data_p (decl))
6587 if (ret == SECCAT_BSS)
6588 ret = SECCAT_SBSS;
6589 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6590 ret = SECCAT_SRODATA;
6591 else
6592 ret = SECCAT_SDATA;
6595 return ret;
6598 static bool
6599 decl_readonly_section_1 (enum section_category category)
6601 switch (category)
6603 case SECCAT_RODATA:
6604 case SECCAT_RODATA_MERGE_STR:
6605 case SECCAT_RODATA_MERGE_STR_INIT:
6606 case SECCAT_RODATA_MERGE_CONST:
6607 case SECCAT_SRODATA:
6608 return true;
6609 default:
6610 return false;
6614 bool
6615 decl_readonly_section (const_tree decl, int reloc)
6617 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6620 /* Select a section based on the above categorization. */
6622 section *
6623 default_elf_select_section (tree decl, int reloc,
6624 unsigned HOST_WIDE_INT align)
6626 const char *sname;
6627 switch (categorize_decl_for_section (decl, reloc))
6629 case SECCAT_TEXT:
6630 /* We're not supposed to be called on FUNCTION_DECLs. */
6631 gcc_unreachable ();
6632 case SECCAT_RODATA:
6633 return readonly_data_section;
6634 case SECCAT_RODATA_MERGE_STR:
6635 return mergeable_string_section (decl, align, 0);
6636 case SECCAT_RODATA_MERGE_STR_INIT:
6637 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6638 case SECCAT_RODATA_MERGE_CONST:
6639 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6640 case SECCAT_SRODATA:
6641 sname = ".sdata2";
6642 break;
6643 case SECCAT_DATA:
6644 return data_section;
6645 case SECCAT_DATA_REL:
6646 sname = ".data.rel";
6647 break;
6648 case SECCAT_DATA_REL_LOCAL:
6649 sname = ".data.rel.local";
6650 break;
6651 case SECCAT_DATA_REL_RO:
6652 sname = ".data.rel.ro";
6653 break;
6654 case SECCAT_DATA_REL_RO_LOCAL:
6655 sname = ".data.rel.ro.local";
6656 break;
6657 case SECCAT_SDATA:
6658 sname = ".sdata";
6659 break;
6660 case SECCAT_TDATA:
6661 sname = ".tdata";
6662 break;
6663 case SECCAT_BSS:
6664 if (bss_section)
6665 return bss_section;
6666 sname = ".bss";
6667 break;
6668 case SECCAT_SBSS:
6669 sname = ".sbss";
6670 break;
6671 case SECCAT_TBSS:
6672 sname = ".tbss";
6673 break;
6674 default:
6675 gcc_unreachable ();
6678 return get_named_section (decl, sname, reloc);
6681 /* Construct a unique section name based on the decl name and the
6682 categorization performed above. */
6684 void
6685 default_unique_section (tree decl, int reloc)
6687 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6688 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6689 const char *prefix, *name, *linkonce;
6690 char *string;
6691 tree id;
6693 switch (categorize_decl_for_section (decl, reloc))
6695 case SECCAT_TEXT:
6696 prefix = one_only ? ".t" : ".text";
6697 break;
6698 case SECCAT_RODATA:
6699 case SECCAT_RODATA_MERGE_STR:
6700 case SECCAT_RODATA_MERGE_STR_INIT:
6701 case SECCAT_RODATA_MERGE_CONST:
6702 prefix = one_only ? ".r" : ".rodata";
6703 break;
6704 case SECCAT_SRODATA:
6705 prefix = one_only ? ".s2" : ".sdata2";
6706 break;
6707 case SECCAT_DATA:
6708 prefix = one_only ? ".d" : ".data";
6709 break;
6710 case SECCAT_DATA_REL:
6711 prefix = one_only ? ".d.rel" : ".data.rel";
6712 break;
6713 case SECCAT_DATA_REL_LOCAL:
6714 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6715 break;
6716 case SECCAT_DATA_REL_RO:
6717 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6718 break;
6719 case SECCAT_DATA_REL_RO_LOCAL:
6720 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6721 break;
6722 case SECCAT_SDATA:
6723 prefix = one_only ? ".s" : ".sdata";
6724 break;
6725 case SECCAT_BSS:
6726 prefix = one_only ? ".b" : ".bss";
6727 break;
6728 case SECCAT_SBSS:
6729 prefix = one_only ? ".sb" : ".sbss";
6730 break;
6731 case SECCAT_TDATA:
6732 prefix = one_only ? ".td" : ".tdata";
6733 break;
6734 case SECCAT_TBSS:
6735 prefix = one_only ? ".tb" : ".tbss";
6736 break;
6737 default:
6738 gcc_unreachable ();
6741 id = DECL_ASSEMBLER_NAME (decl);
6742 ultimate_transparent_alias_target (&id);
6743 name = IDENTIFIER_POINTER (id);
6744 name = targetm.strip_name_encoding (name);
6746 /* If we're using one_only, then there needs to be a .gnu.linkonce
6747 prefix to the section name. */
6748 linkonce = one_only ? ".gnu.linkonce" : "";
6750 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6752 set_decl_section_name (decl, string);
6755 /* Subroutine of compute_reloc_for_rtx for leaf rtxes. */
6757 static int
6758 compute_reloc_for_rtx_1 (const_rtx x)
6760 switch (GET_CODE (x))
6762 case SYMBOL_REF:
6763 return SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6764 case LABEL_REF:
6765 return 1;
6766 default:
6767 return 0;
6771 /* Like compute_reloc_for_constant, except for an RTX. The return value
6772 is a mask for which bit 1 indicates a global relocation, and bit 0
6773 indicates a local relocation. */
6775 static int
6776 compute_reloc_for_rtx (const_rtx x)
6778 switch (GET_CODE (x))
6780 case SYMBOL_REF:
6781 case LABEL_REF:
6782 return compute_reloc_for_rtx_1 (x);
6784 case CONST:
6786 int reloc = 0;
6787 subrtx_iterator::array_type array;
6788 FOR_EACH_SUBRTX (iter, array, x, ALL)
6789 reloc |= compute_reloc_for_rtx_1 (*iter);
6790 return reloc;
6793 default:
6794 return 0;
6798 section *
6799 default_select_rtx_section (machine_mode mode ATTRIBUTE_UNUSED,
6800 rtx x,
6801 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6803 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6804 return data_section;
6805 else
6806 return readonly_data_section;
6809 section *
6810 default_elf_select_rtx_section (machine_mode mode, rtx x,
6811 unsigned HOST_WIDE_INT align)
6813 int reloc = compute_reloc_for_rtx (x);
6815 /* ??? Handle small data here somehow. */
6817 if (reloc & targetm.asm_out.reloc_rw_mask ())
6819 if (reloc == 1)
6820 return get_named_section (NULL, ".data.rel.ro.local", 1);
6821 else
6822 return get_named_section (NULL, ".data.rel.ro", 3);
6825 return mergeable_constant_section (mode, align, 0);
6828 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6830 void
6831 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6833 rtx symbol;
6834 int flags;
6836 /* Careful not to prod global register variables. */
6837 if (!MEM_P (rtl))
6838 return;
6839 symbol = XEXP (rtl, 0);
6840 if (GET_CODE (symbol) != SYMBOL_REF)
6841 return;
6843 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6844 if (TREE_CODE (decl) == FUNCTION_DECL)
6845 flags |= SYMBOL_FLAG_FUNCTION;
6846 if (targetm.binds_local_p (decl))
6847 flags |= SYMBOL_FLAG_LOCAL;
6848 if (VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6849 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6850 else if (targetm.in_small_data_p (decl))
6851 flags |= SYMBOL_FLAG_SMALL;
6852 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6853 being PUBLIC, the thing *must* be defined in this translation unit.
6854 Prevent this buglet from being propagated into rtl code as well. */
6855 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6856 flags |= SYMBOL_FLAG_EXTERNAL;
6858 SYMBOL_REF_FLAGS (symbol) = flags;
6861 /* By default, we do nothing for encode_section_info, so we need not
6862 do anything but discard the '*' marker. */
6864 const char *
6865 default_strip_name_encoding (const char *str)
6867 return str + (*str == '*');
6870 #ifdef ASM_OUTPUT_DEF
6871 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6872 anchor relative to ".", the current section position. */
6874 void
6875 default_asm_output_anchor (rtx symbol)
6877 char buffer[100];
6879 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6880 SYMBOL_REF_BLOCK_OFFSET (symbol));
6881 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6883 #endif
6885 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6887 bool
6888 default_use_anchors_for_symbol_p (const_rtx symbol)
6890 section *sect;
6891 tree decl;
6893 /* Don't use anchors for mergeable sections. The linker might move
6894 the objects around. */
6895 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6896 if (sect->common.flags & SECTION_MERGE)
6897 return false;
6899 /* Don't use anchors for small data sections. The small data register
6900 acts as an anchor for such sections. */
6901 if (sect->common.flags & SECTION_SMALL)
6902 return false;
6904 decl = SYMBOL_REF_DECL (symbol);
6905 if (decl && DECL_P (decl))
6907 /* Don't use section anchors for decls that might be defined or
6908 usurped by other modules. */
6909 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6910 return false;
6912 /* Don't use section anchors for decls that will be placed in a
6913 small data section. */
6914 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6915 one above. The problem is that we only use SECTION_SMALL for
6916 sections that should be marked as small in the section directive. */
6917 if (targetm.in_small_data_p (decl))
6918 return false;
6920 /* Don't use section anchors for decls that won't fit inside a single
6921 anchor range to reduce the amount of instructions required to refer
6922 to the entire declaration. */
6923 if (DECL_SIZE_UNIT (decl) == NULL_TREE
6924 || !tree_fits_uhwi_p (DECL_SIZE_UNIT (decl))
6925 || (tree_to_uhwi (DECL_SIZE_UNIT (decl))
6926 >= (unsigned HOST_WIDE_INT) targetm.max_anchor_offset))
6927 return false;
6930 return true;
6933 /* Return true when RESOLUTION indicate that symbol will be bound to the
6934 definition provided by current .o file. */
6936 static bool
6937 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
6939 return (resolution == LDPR_PREVAILING_DEF
6940 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6941 || resolution == LDPR_PREVAILING_DEF_IRONLY);
6944 /* Return true when RESOLUTION indicate that symbol will be bound locally
6945 within current executable or DSO. */
6947 static bool
6948 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
6950 return (resolution == LDPR_PREVAILING_DEF
6951 || resolution == LDPR_PREVAILING_DEF_IRONLY
6952 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6953 || resolution == LDPR_PREEMPTED_REG
6954 || resolution == LDPR_PREEMPTED_IR
6955 || resolution == LDPR_RESOLVED_IR
6956 || resolution == LDPR_RESOLVED_EXEC);
6959 /* COMMON_LOCAL_P is true means that the linker can guarantee that an
6960 uninitialized common symbol in the executable will still be defined
6961 (through COPY relocation) in the executable. */
6963 bool
6964 default_binds_local_p_3 (const_tree exp, bool shlib, bool weak_dominate,
6965 bool extern_protected_data, bool common_local_p)
6967 /* A non-decl is an entry in the constant pool. */
6968 if (!DECL_P (exp))
6969 return true;
6971 /* Weakrefs may not bind locally, even though the weakref itself is always
6972 static and therefore local. Similarly, the resolver for ifunc functions
6973 might resolve to a non-local function.
6974 FIXME: We can resolve the weakref case more curefuly by looking at the
6975 weakref alias. */
6976 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
6977 || (TREE_CODE (exp) == FUNCTION_DECL
6978 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
6979 return false;
6981 /* Static variables are always local. */
6982 if (! TREE_PUBLIC (exp))
6983 return true;
6985 /* With resolution file in hand, take look into resolutions.
6986 We can't just return true for resolved_locally symbols,
6987 because dynamic linking might overwrite symbols
6988 in shared libraries. */
6989 bool resolved_locally = false;
6991 bool uninited_common = (DECL_COMMON (exp)
6992 && (DECL_INITIAL (exp) == NULL
6993 || (!in_lto_p
6994 && DECL_INITIAL (exp) == error_mark_node)));
6996 /* A non-external variable is defined locally only if it isn't
6997 uninitialized COMMON variable or common_local_p is true. */
6998 bool defined_locally = (!DECL_EXTERNAL (exp)
6999 && (!uninited_common || common_local_p));
7000 if (symtab_node *node = symtab_node::get (exp))
7002 if (node->in_other_partition)
7003 defined_locally = true;
7004 if (node->can_be_discarded_p ())
7006 else if (resolution_to_local_definition_p (node->resolution))
7007 defined_locally = resolved_locally = true;
7008 else if (resolution_local_p (node->resolution))
7009 resolved_locally = true;
7011 if (defined_locally && weak_dominate && !shlib)
7012 resolved_locally = true;
7014 /* Undefined weak symbols are never defined locally. */
7015 if (DECL_WEAK (exp) && !defined_locally)
7016 return false;
7018 /* A symbol is local if the user has said explicitly that it will be,
7019 or if we have a definition for the symbol. We cannot infer visibility
7020 for undefined symbols. */
7021 if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT
7022 && (TREE_CODE (exp) == FUNCTION_DECL
7023 || !extern_protected_data
7024 || DECL_VISIBILITY (exp) != VISIBILITY_PROTECTED)
7025 && (DECL_VISIBILITY_SPECIFIED (exp) || defined_locally))
7026 return true;
7028 /* If PIC, then assume that any global name can be overridden by
7029 symbols resolved from other modules. */
7030 if (shlib)
7031 return false;
7033 /* Variables defined outside this object might not be local. */
7034 if (DECL_EXTERNAL (exp) && !resolved_locally)
7035 return false;
7037 /* Non-dominant weak symbols are not defined locally. */
7038 if (DECL_WEAK (exp) && !resolved_locally)
7039 return false;
7041 /* Uninitialized COMMON variable may be unified with symbols
7042 resolved from other modules. */
7043 if (uninited_common && !resolved_locally)
7044 return false;
7046 /* Otherwise we're left with initialized (or non-common) global data
7047 which is of necessity defined locally. */
7048 return true;
7051 /* Assume ELF-ish defaults, since that's pretty much the most liberal
7052 wrt cross-module name binding. */
7054 bool
7055 default_binds_local_p (const_tree exp)
7057 return default_binds_local_p_3 (exp, flag_shlib != 0, true, false, false);
7060 /* Similar to default_binds_local_p, but common symbol may be local and
7061 extern protected data is non-local. */
7063 bool
7064 default_binds_local_p_2 (const_tree exp)
7066 return default_binds_local_p_3 (exp, flag_shlib != 0, true, true,
7067 !flag_pic);
7070 bool
7071 default_binds_local_p_1 (const_tree exp, int shlib)
7073 return default_binds_local_p_3 (exp, shlib != 0, false, false, false);
7076 /* Return true when references to DECL must bind to current definition in
7077 final executable.
7079 The condition is usually equivalent to whether the function binds to the
7080 current module (shared library or executable), that is to binds_local_p.
7081 We use this fact to avoid need for another target hook and implement
7082 the logic using binds_local_p and just special cases where
7083 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
7084 the weak definitions (that can be overwritten at linktime by other
7085 definition from different object file) and when resolution info is available
7086 we simply use the knowledge passed to us by linker plugin. */
7087 bool
7088 decl_binds_to_current_def_p (const_tree decl)
7090 gcc_assert (DECL_P (decl));
7091 if (!targetm.binds_local_p (decl))
7092 return false;
7093 if (!TREE_PUBLIC (decl))
7094 return true;
7096 /* When resolution is available, just use it. */
7097 if (symtab_node *node = symtab_node::get (decl))
7099 if (node->resolution != LDPR_UNKNOWN
7100 && !node->can_be_discarded_p ())
7101 return resolution_to_local_definition_p (node->resolution);
7104 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
7105 binds locally but still can be overwritten), DECL_COMMON (can be merged
7106 with a non-common definition somewhere in the same module) or
7107 DECL_EXTERNAL.
7108 This rely on fact that binds_local_p behave as decl_replaceable_p
7109 for all other declaration types. */
7110 if (DECL_WEAK (decl))
7111 return false;
7112 if (DECL_COMMON (decl)
7113 && (DECL_INITIAL (decl) == NULL
7114 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
7115 return false;
7116 if (DECL_EXTERNAL (decl))
7117 return false;
7118 return true;
7121 /* A replaceable function or variable is one which may be replaced
7122 at link-time with an entirely different definition, provided that the
7123 replacement has the same type. For example, functions declared
7124 with __attribute__((weak)) on most systems are replaceable.
7126 COMDAT functions are not replaceable, since all definitions of the
7127 function must be equivalent. It is important that COMDAT functions
7128 not be treated as replaceable so that use of C++ template
7129 instantiations is not penalized. */
7131 bool
7132 decl_replaceable_p (tree decl)
7134 gcc_assert (DECL_P (decl));
7135 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
7136 return false;
7137 if (!flag_semantic_interposition
7138 && !DECL_WEAK (decl))
7139 return false;
7140 return !decl_binds_to_current_def_p (decl);
7143 /* Default function to output code that will globalize a label. A
7144 target must define GLOBAL_ASM_OP or provide its own function to
7145 globalize a label. */
7146 #ifdef GLOBAL_ASM_OP
7147 void
7148 default_globalize_label (FILE * stream, const char *name)
7150 fputs (GLOBAL_ASM_OP, stream);
7151 assemble_name (stream, name);
7152 putc ('\n', stream);
7154 #endif /* GLOBAL_ASM_OP */
7156 /* Default function to output code that will globalize a declaration. */
7157 void
7158 default_globalize_decl_name (FILE * stream, tree decl)
7160 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
7161 targetm.asm_out.globalize_label (stream, name);
7164 /* Default function to output a label for unwind information. The
7165 default is to do nothing. A target that needs nonlocal labels for
7166 unwind information must provide its own function to do this. */
7167 void
7168 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
7169 tree decl ATTRIBUTE_UNUSED,
7170 int for_eh ATTRIBUTE_UNUSED,
7171 int empty ATTRIBUTE_UNUSED)
7175 /* Default function to output a label to divide up the exception table.
7176 The default is to do nothing. A target that needs/wants to divide
7177 up the table must provide it's own function to do this. */
7178 void
7179 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
7183 /* This is how to output an internal numbered label where PREFIX is
7184 the class of label and LABELNO is the number within the class. */
7186 void
7187 default_generate_internal_label (char *buf, const char *prefix,
7188 unsigned long labelno)
7190 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
7193 /* This is how to output an internal numbered label where PREFIX is
7194 the class of label and LABELNO is the number within the class. */
7196 void
7197 default_internal_label (FILE *stream, const char *prefix,
7198 unsigned long labelno)
7200 char *const buf = (char *) alloca (40 + strlen (prefix));
7201 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
7202 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
7206 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
7208 void
7209 default_asm_declare_constant_name (FILE *file, const char *name,
7210 const_tree exp ATTRIBUTE_UNUSED,
7211 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
7213 assemble_label (file, name);
7216 /* This is the default behavior at the beginning of a file. It's
7217 controlled by two other target-hook toggles. */
7218 void
7219 default_file_start (void)
7221 if (targetm.asm_file_start_app_off
7222 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
7223 fputs (ASM_APP_OFF, asm_out_file);
7225 if (targetm.asm_file_start_file_directive)
7227 /* LTO produced units have no meaningful main_input_filename. */
7228 if (in_lto_p)
7229 output_file_directive (asm_out_file, "<artificial>");
7230 else
7231 output_file_directive (asm_out_file, main_input_filename);
7235 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
7236 which emits a special section directive used to indicate whether or
7237 not this object file needs an executable stack. This is primarily
7238 a GNU extension to ELF but could be used on other targets. */
7240 int trampolines_created;
7242 void
7243 file_end_indicate_exec_stack (void)
7245 unsigned int flags = SECTION_DEBUG;
7246 if (trampolines_created)
7247 flags |= SECTION_CODE;
7249 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
7252 /* Emit a special section directive to indicate that this object file
7253 was compiled with -fsplit-stack. This is used to let the linker
7254 detect calls between split-stack code and non-split-stack code, so
7255 that it can modify the split-stack code to allocate a sufficiently
7256 large stack. We emit another special section if there are any
7257 functions in this file which have the no_split_stack attribute, to
7258 prevent the linker from warning about being unable to convert the
7259 functions if they call non-split-stack code. */
7261 void
7262 file_end_indicate_split_stack (void)
7264 if (flag_split_stack)
7266 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
7267 NULL));
7268 if (saw_no_split_stack)
7269 switch_to_section (get_section (".note.GNU-no-split-stack",
7270 SECTION_DEBUG, NULL));
7274 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
7275 a get_unnamed_section callback. */
7277 void
7278 output_section_asm_op (const void *directive)
7280 fprintf (asm_out_file, "%s\n", (const char *) directive);
7283 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
7284 the current section is NEW_SECTION. */
7286 void
7287 switch_to_section (section *new_section)
7289 if (in_section == new_section)
7290 return;
7292 if (new_section->common.flags & SECTION_FORGET)
7293 in_section = NULL;
7294 else
7295 in_section = new_section;
7297 switch (SECTION_STYLE (new_section))
7299 case SECTION_NAMED:
7300 targetm.asm_out.named_section (new_section->named.name,
7301 new_section->named.common.flags,
7302 new_section->named.decl);
7303 break;
7305 case SECTION_UNNAMED:
7306 new_section->unnamed.callback (new_section->unnamed.data);
7307 break;
7309 case SECTION_NOSWITCH:
7310 gcc_unreachable ();
7311 break;
7314 new_section->common.flags |= SECTION_DECLARED;
7317 /* If block symbol SYMBOL has not yet been assigned an offset, place
7318 it at the end of its block. */
7320 void
7321 place_block_symbol (rtx symbol)
7323 unsigned HOST_WIDE_INT size, mask, offset;
7324 struct constant_descriptor_rtx *desc;
7325 unsigned int alignment;
7326 struct object_block *block;
7327 tree decl;
7329 gcc_assert (SYMBOL_REF_BLOCK (symbol));
7330 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7331 return;
7333 /* Work out the symbol's size and alignment. */
7334 if (CONSTANT_POOL_ADDRESS_P (symbol))
7336 desc = SYMBOL_REF_CONSTANT (symbol);
7337 alignment = desc->align;
7338 size = GET_MODE_SIZE (desc->mode);
7340 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7342 decl = SYMBOL_REF_DECL (symbol);
7343 gcc_checking_assert (DECL_IN_CONSTANT_POOL (decl));
7344 alignment = DECL_ALIGN (decl);
7345 size = get_constant_size (DECL_INITIAL (decl));
7346 if ((flag_sanitize & SANITIZE_ADDRESS)
7347 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7348 && asan_protect_global (DECL_INITIAL (decl)))
7350 size += asan_red_zone_size (size);
7351 alignment = MAX (alignment,
7352 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7355 else
7357 struct symtab_node *snode;
7358 decl = SYMBOL_REF_DECL (symbol);
7360 snode = symtab_node::get (decl);
7361 if (snode->alias)
7363 rtx target = DECL_RTL (snode->ultimate_alias_target ()->decl);
7365 gcc_assert (MEM_P (target)
7366 && GET_CODE (XEXP (target, 0)) == SYMBOL_REF
7367 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (target, 0)));
7368 target = XEXP (target, 0);
7369 place_block_symbol (target);
7370 SYMBOL_REF_BLOCK_OFFSET (symbol) = SYMBOL_REF_BLOCK_OFFSET (target);
7371 return;
7373 alignment = get_variable_align (decl);
7374 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7375 if ((flag_sanitize & SANITIZE_ADDRESS)
7376 && asan_protect_global (decl))
7378 size += asan_red_zone_size (size);
7379 alignment = MAX (alignment,
7380 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7384 /* Calculate the object's offset from the start of the block. */
7385 block = SYMBOL_REF_BLOCK (symbol);
7386 mask = alignment / BITS_PER_UNIT - 1;
7387 offset = (block->size + mask) & ~mask;
7388 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7390 /* Record the block's new alignment and size. */
7391 block->alignment = MAX (block->alignment, alignment);
7392 block->size = offset + size;
7394 vec_safe_push (block->objects, symbol);
7397 /* Return the anchor that should be used to address byte offset OFFSET
7398 from the first object in BLOCK. MODEL is the TLS model used
7399 to access it. */
7402 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7403 enum tls_model model)
7405 char label[100];
7406 unsigned int begin, middle, end;
7407 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7408 rtx anchor;
7410 /* Work out the anchor's offset. Use an offset of 0 for the first
7411 anchor so that we don't pessimize the case where we take the address
7412 of a variable at the beginning of the block. This is particularly
7413 useful when a block has only one variable assigned to it.
7415 We try to place anchors RANGE bytes apart, so there can then be
7416 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7417 a ptr_mode offset. With some target settings, the lowest such
7418 anchor might be out of range for the lowest ptr_mode offset;
7419 likewise the highest anchor for the highest offset. Use anchors
7420 at the extreme ends of the ptr_mode range in such cases.
7422 All arithmetic uses unsigned integers in order to avoid
7423 signed overflow. */
7424 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7425 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7426 range = max_offset - min_offset + 1;
7427 if (range == 0)
7428 offset = 0;
7429 else
7431 bias = HOST_WIDE_INT_1U << (GET_MODE_BITSIZE (ptr_mode) - 1);
7432 if (offset < 0)
7434 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7435 delta -= delta % range;
7436 if (delta > bias)
7437 delta = bias;
7438 offset = (HOST_WIDE_INT) (-delta);
7440 else
7442 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7443 delta -= delta % range;
7444 if (delta > bias - 1)
7445 delta = bias - 1;
7446 offset = (HOST_WIDE_INT) delta;
7450 /* Do a binary search to see if there's already an anchor we can use.
7451 Set BEGIN to the new anchor's index if not. */
7452 begin = 0;
7453 end = vec_safe_length (block->anchors);
7454 while (begin != end)
7456 middle = (end + begin) / 2;
7457 anchor = (*block->anchors)[middle];
7458 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7459 end = middle;
7460 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7461 begin = middle + 1;
7462 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7463 end = middle;
7464 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7465 begin = middle + 1;
7466 else
7467 return anchor;
7470 /* Create a new anchor with a unique label. */
7471 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7472 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7473 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7474 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7476 /* Insert it at index BEGIN. */
7477 vec_safe_insert (block->anchors, begin, anchor);
7478 return anchor;
7481 /* Output the objects in BLOCK. */
7483 static void
7484 output_object_block (struct object_block *block)
7486 struct constant_descriptor_rtx *desc;
7487 unsigned int i;
7488 HOST_WIDE_INT offset;
7489 tree decl;
7490 rtx symbol;
7492 if (!block->objects)
7493 return;
7495 /* Switch to the section and make sure that the first byte is
7496 suitably aligned. */
7497 /* Special case VTV comdat sections similar to assemble_variable. */
7498 if (SECTION_STYLE (block->sect) == SECTION_NAMED
7499 && block->sect->named.name
7500 && (strcmp (block->sect->named.name, ".vtable_map_vars") == 0))
7501 handle_vtv_comdat_section (block->sect, block->sect->named.decl);
7502 else
7503 switch_to_section (block->sect);
7505 assemble_align (block->alignment);
7507 /* Define the values of all anchors relative to the current section
7508 position. */
7509 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7510 targetm.asm_out.output_anchor (symbol);
7512 /* Output the objects themselves. */
7513 offset = 0;
7514 FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7516 /* Move to the object's offset, padding with zeros if necessary. */
7517 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7518 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7519 if (CONSTANT_POOL_ADDRESS_P (symbol))
7521 desc = SYMBOL_REF_CONSTANT (symbol);
7522 /* Pass 1 for align as we have already laid out everything in the block.
7523 So aligning shouldn't be necessary. */
7524 output_constant_pool_1 (desc, 1);
7525 offset += GET_MODE_SIZE (desc->mode);
7527 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7529 HOST_WIDE_INT size;
7530 decl = SYMBOL_REF_DECL (symbol);
7531 assemble_constant_contents
7532 (DECL_INITIAL (decl), XSTR (symbol, 0), DECL_ALIGN (decl));
7534 size = get_constant_size (DECL_INITIAL (decl));
7535 offset += size;
7536 if ((flag_sanitize & SANITIZE_ADDRESS)
7537 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7538 && asan_protect_global (DECL_INITIAL (decl)))
7540 size = asan_red_zone_size (size);
7541 assemble_zeros (size);
7542 offset += size;
7545 else
7547 HOST_WIDE_INT size;
7548 decl = SYMBOL_REF_DECL (symbol);
7549 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7550 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7551 offset += size;
7552 if ((flag_sanitize & SANITIZE_ADDRESS)
7553 && asan_protect_global (decl))
7555 size = asan_red_zone_size (size);
7556 assemble_zeros (size);
7557 offset += size;
7563 /* A callback for qsort to compare object_blocks. */
7565 static int
7566 output_object_block_compare (const void *x, const void *y)
7568 object_block *p1 = *(object_block * const*)x;
7569 object_block *p2 = *(object_block * const*)y;
7571 if (p1->sect->common.flags & SECTION_NAMED
7572 && !(p2->sect->common.flags & SECTION_NAMED))
7573 return 1;
7575 if (!(p1->sect->common.flags & SECTION_NAMED)
7576 && p2->sect->common.flags & SECTION_NAMED)
7577 return -1;
7579 if (p1->sect->common.flags & SECTION_NAMED
7580 && p2->sect->common.flags & SECTION_NAMED)
7581 return strcmp (p1->sect->named.name, p2->sect->named.name);
7583 unsigned f1 = p1->sect->common.flags;
7584 unsigned f2 = p2->sect->common.flags;
7585 if (f1 == f2)
7586 return 0;
7587 return f1 < f2 ? -1 : 1;
7590 /* Output the definitions of all object_blocks. */
7592 void
7593 output_object_blocks (void)
7595 vec<object_block *, va_heap> v;
7596 v.create (object_block_htab->elements ());
7597 object_block *obj;
7598 hash_table<object_block_hasher>::iterator hi;
7600 FOR_EACH_HASH_TABLE_ELEMENT (*object_block_htab, obj, object_block *, hi)
7601 v.quick_push (obj);
7603 /* Sort them in order to output them in a deterministic manner,
7604 otherwise we may get .rodata sections in different orders with
7605 and without -g. */
7606 v.qsort (output_object_block_compare);
7607 unsigned i;
7608 FOR_EACH_VEC_ELT (v, i, obj)
7609 output_object_block (obj);
7611 v.release ();
7614 /* This function provides a possible implementation of the
7615 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7616 by -frecord-gcc-switches it creates a new mergeable, string section in the
7617 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7618 contains the switches in ASCII format.
7620 FIXME: This code does not correctly handle double quote characters
7621 that appear inside strings, (it strips them rather than preserving them).
7622 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7623 characters - instead it treats them as sub-string separators. Since
7624 we want to emit NUL strings terminators into the object file we have to use
7625 ASM_OUTPUT_SKIP. */
7628 elf_record_gcc_switches (print_switch_type type, const char * name)
7630 switch (type)
7632 case SWITCH_TYPE_PASSED:
7633 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7634 ASM_OUTPUT_SKIP (asm_out_file, HOST_WIDE_INT_1U);
7635 break;
7637 case SWITCH_TYPE_DESCRIPTIVE:
7638 if (name == NULL)
7640 /* Distinguish between invocations where name is NULL. */
7641 static bool started = false;
7643 if (!started)
7645 section * sec;
7647 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7648 SECTION_DEBUG
7649 | SECTION_MERGE
7650 | SECTION_STRINGS
7651 | (SECTION_ENTSIZE & 1),
7652 NULL);
7653 switch_to_section (sec);
7654 started = true;
7658 default:
7659 break;
7662 /* The return value is currently ignored by the caller, but must be 0.
7663 For -fverbose-asm the return value would be the number of characters
7664 emitted into the assembler file. */
7665 return 0;
7668 /* Emit text to declare externally defined symbols. It is needed to
7669 properly support non-default visibility. */
7670 void
7671 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7672 tree decl,
7673 const char *name ATTRIBUTE_UNUSED)
7675 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7676 set in order to avoid putting out names that are never really
7677 used. Always output visibility specified in the source. */
7678 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7679 && (DECL_VISIBILITY_SPECIFIED (decl)
7680 || targetm.binds_local_p (decl)))
7681 maybe_assemble_visibility (decl);
7684 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7686 void
7687 default_asm_output_source_filename (FILE *file, const char *name)
7689 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7690 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7691 #else
7692 fprintf (file, "\t.file\t");
7693 output_quoted_string (file, name);
7694 putc ('\n', file);
7695 #endif
7698 /* Output a file name in the form wanted by System V. */
7700 void
7701 output_file_directive (FILE *asm_file, const char *input_name)
7703 int len;
7704 const char *na;
7706 if (input_name == NULL)
7707 input_name = "<stdin>";
7708 else
7709 input_name = remap_debug_filename (input_name);
7711 len = strlen (input_name);
7712 na = input_name + len;
7714 /* NA gets INPUT_NAME sans directory names. */
7715 while (na > input_name)
7717 if (IS_DIR_SEPARATOR (na[-1]))
7718 break;
7719 na--;
7722 targetm.asm_out.output_source_filename (asm_file, na);
7725 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7726 EXP. */
7728 make_debug_expr_from_rtl (const_rtx exp)
7730 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7731 machine_mode mode = GET_MODE (exp);
7732 rtx dval;
7734 DECL_ARTIFICIAL (ddecl) = 1;
7735 if (REG_P (exp) && REG_EXPR (exp))
7736 type = TREE_TYPE (REG_EXPR (exp));
7737 else if (MEM_P (exp) && MEM_EXPR (exp))
7738 type = TREE_TYPE (MEM_EXPR (exp));
7739 else
7740 type = NULL_TREE;
7741 if (type && TYPE_MODE (type) == mode)
7742 TREE_TYPE (ddecl) = type;
7743 else
7744 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7745 SET_DECL_MODE (ddecl, mode);
7746 dval = gen_rtx_DEBUG_EXPR (mode);
7747 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7748 SET_DECL_RTL (ddecl, dval);
7749 return dval;
7752 #ifdef ELF_ASCII_ESCAPES
7753 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7755 void
7756 default_elf_asm_output_limited_string (FILE *f, const char *s)
7758 int escape;
7759 unsigned char c;
7761 fputs (STRING_ASM_OP, f);
7762 putc ('"', f);
7763 while (*s != '\0')
7765 c = *s;
7766 escape = ELF_ASCII_ESCAPES[c];
7767 switch (escape)
7769 case 0:
7770 putc (c, f);
7771 break;
7772 case 1:
7773 putc ('\\', f);
7774 putc ('0'+((c>>6)&7), f);
7775 putc ('0'+((c>>3)&7), f);
7776 putc ('0'+(c&7), f);
7777 break;
7778 default:
7779 putc ('\\', f);
7780 putc (escape, f);
7781 break;
7783 s++;
7785 putc ('\"', f);
7786 putc ('\n', f);
7789 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7791 void
7792 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7794 const char *limit = s + len;
7795 const char *last_null = NULL;
7796 unsigned bytes_in_chunk = 0;
7797 unsigned char c;
7798 int escape;
7800 for (; s < limit; s++)
7802 const char *p;
7804 if (bytes_in_chunk >= 60)
7806 putc ('\"', f);
7807 putc ('\n', f);
7808 bytes_in_chunk = 0;
7811 if (s > last_null)
7813 for (p = s; p < limit && *p != '\0'; p++)
7814 continue;
7815 last_null = p;
7817 else
7818 p = last_null;
7820 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7822 if (bytes_in_chunk > 0)
7824 putc ('\"', f);
7825 putc ('\n', f);
7826 bytes_in_chunk = 0;
7829 default_elf_asm_output_limited_string (f, s);
7830 s = p;
7832 else
7834 if (bytes_in_chunk == 0)
7835 fputs (ASCII_DATA_ASM_OP "\"", f);
7837 c = *s;
7838 escape = ELF_ASCII_ESCAPES[c];
7839 switch (escape)
7841 case 0:
7842 putc (c, f);
7843 bytes_in_chunk++;
7844 break;
7845 case 1:
7846 putc ('\\', f);
7847 putc ('0'+((c>>6)&7), f);
7848 putc ('0'+((c>>3)&7), f);
7849 putc ('0'+(c&7), f);
7850 bytes_in_chunk += 4;
7851 break;
7852 default:
7853 putc ('\\', f);
7854 putc (escape, f);
7855 bytes_in_chunk += 2;
7856 break;
7862 if (bytes_in_chunk > 0)
7864 putc ('\"', f);
7865 putc ('\n', f);
7868 #endif
7870 static GTY(()) section *elf_init_array_section;
7871 static GTY(()) section *elf_fini_array_section;
7873 static section *
7874 get_elf_initfini_array_priority_section (int priority,
7875 bool constructor_p)
7877 section *sec;
7878 if (priority != DEFAULT_INIT_PRIORITY)
7880 char buf[18];
7881 sprintf (buf, "%s.%.5u",
7882 constructor_p ? ".init_array" : ".fini_array",
7883 priority);
7884 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7886 else
7888 if (constructor_p)
7890 if (elf_init_array_section == NULL)
7891 elf_init_array_section
7892 = get_section (".init_array",
7893 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7894 sec = elf_init_array_section;
7896 else
7898 if (elf_fini_array_section == NULL)
7899 elf_fini_array_section
7900 = get_section (".fini_array",
7901 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7902 sec = elf_fini_array_section;
7905 return sec;
7908 /* Use .init_array section for constructors. */
7910 void
7911 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7913 section *sec = get_elf_initfini_array_priority_section (priority,
7914 true);
7915 assemble_addr_to_section (symbol, sec);
7918 /* Use .fini_array section for destructors. */
7920 void
7921 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7923 section *sec = get_elf_initfini_array_priority_section (priority,
7924 false);
7925 assemble_addr_to_section (symbol, sec);
7928 /* Default TARGET_ASM_OUTPUT_IDENT hook.
7930 This is a bit of a cheat. The real default is a no-op, but this
7931 hook is the default for all targets with a .ident directive. */
7933 void
7934 default_asm_output_ident_directive (const char *ident_str)
7936 const char *ident_asm_op = "\t.ident\t";
7938 /* If we are still in the front end, do not write out the string
7939 to asm_out_file. Instead, add a fake top-level asm statement.
7940 This allows the front ends to use this hook without actually
7941 writing to asm_out_file, to handle #ident or Pragma Ident. */
7942 if (symtab->state == PARSING)
7944 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
7945 symtab->finalize_toplevel_asm (build_string (strlen (buf), buf));
7947 else
7948 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
7952 /* This function ensures that vtable_map variables are not only
7953 in the comdat section, but that each variable has its own unique
7954 comdat name. Without this the variables end up in the same section
7955 with a single comdat name.
7957 FIXME: resolve_unique_section needs to deal better with
7958 decls with both DECL_SECTION_NAME and DECL_ONE_ONLY. Once
7959 that is fixed, this if-else statement can be replaced with
7960 a single call to "switch_to_section (sect)". */
7962 static void
7963 handle_vtv_comdat_section (section *sect, const_tree decl ATTRIBUTE_UNUSED)
7965 #if defined (OBJECT_FORMAT_ELF)
7966 targetm.asm_out.named_section (sect->named.name,
7967 sect->named.common.flags
7968 | SECTION_LINKONCE,
7969 DECL_NAME (decl));
7970 in_section = sect;
7971 #else
7972 /* Neither OBJECT_FORMAT_PE, nor OBJECT_FORMAT_COFF is set here.
7973 Therefore the following check is used.
7974 In case a the target is PE or COFF a comdat group section
7975 is created, e.g. .vtable_map_vars$foo. The linker places
7976 everything in .vtable_map_vars at the end.
7978 A fix could be made in
7979 gcc/config/i386/winnt.c: i386_pe_unique_section. */
7980 if (TARGET_PECOFF)
7982 char *name;
7984 if (TREE_CODE (DECL_NAME (decl)) == IDENTIFIER_NODE)
7985 name = ACONCAT ((sect->named.name, "$",
7986 IDENTIFIER_POINTER (DECL_NAME (decl)), NULL));
7987 else
7988 name = ACONCAT ((sect->named.name, "$",
7989 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (DECL_NAME (decl))),
7990 NULL));
7992 targetm.asm_out.named_section (name,
7993 sect->named.common.flags
7994 | SECTION_LINKONCE,
7995 DECL_NAME (decl));
7996 in_section = sect;
7998 else
7999 switch_to_section (sect);
8000 #endif
8003 #include "gt-varasm.h"