* gcc.dg/ipa/inlinehint-4.c: Also pass --param inline-unit-growth=20.
[official-gcc.git] / gcc / varasm.c
blobea79893a547e746615b10c80948ea60444d4f013
1 /* Output variables, constants and external declarations, for GNU compiler.
2 Copyright (C) 1987-2018 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 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
847 && mode != VOIDmode
848 && mode != BLKmode
849 && known_le (GET_MODE_BITSIZE (mode), align)
850 && align >= 8
851 && align <= 256
852 && (align & (align - 1)) == 0)
854 const char *prefix = function_mergeable_rodata_prefix ();
855 char *name = (char *) alloca (strlen (prefix) + 30);
857 sprintf (name, "%s.cst%d", prefix, (int) (align / 8));
858 flags |= (align / 8) | SECTION_MERGE;
859 return get_section (name, flags, NULL);
861 return readonly_data_section;
864 /* Given NAME, a putative register name, discard any customary prefixes. */
866 static const char *
867 strip_reg_name (const char *name)
869 #ifdef REGISTER_PREFIX
870 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
871 name += strlen (REGISTER_PREFIX);
872 #endif
873 if (name[0] == '%' || name[0] == '#')
874 name++;
875 return name;
878 /* The user has asked for a DECL to have a particular name. Set (or
879 change) it in such a way that we don't prefix an underscore to
880 it. */
881 void
882 set_user_assembler_name (tree decl, const char *name)
884 char *starred = (char *) alloca (strlen (name) + 2);
885 starred[0] = '*';
886 strcpy (starred + 1, name);
887 symtab->change_decl_assembler_name (decl, get_identifier (starred));
888 SET_DECL_RTL (decl, NULL_RTX);
891 /* Decode an `asm' spec for a declaration as a register name.
892 Return the register number, or -1 if nothing specified,
893 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
894 or -3 if ASMSPEC is `cc' and is not recognized,
895 or -4 if ASMSPEC is `memory' and is not recognized.
896 Accept an exact spelling or a decimal number.
897 Prefixes such as % are optional. */
900 decode_reg_name_and_count (const char *asmspec, int *pnregs)
902 /* Presume just one register is clobbered. */
903 *pnregs = 1;
905 if (asmspec != 0)
907 int i;
909 /* Get rid of confusing prefixes. */
910 asmspec = strip_reg_name (asmspec);
912 /* Allow a decimal number as a "register name". */
913 for (i = strlen (asmspec) - 1; i >= 0; i--)
914 if (! ISDIGIT (asmspec[i]))
915 break;
916 if (asmspec[0] != 0 && i < 0)
918 i = atoi (asmspec);
919 if (i < FIRST_PSEUDO_REGISTER && i >= 0 && reg_names[i][0])
920 return i;
921 else
922 return -2;
925 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
926 if (reg_names[i][0]
927 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
928 return i;
930 #ifdef OVERLAPPING_REGISTER_NAMES
932 static const struct
934 const char *const name;
935 const int number;
936 const int nregs;
937 } table[] = OVERLAPPING_REGISTER_NAMES;
939 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
940 if (table[i].name[0]
941 && ! strcmp (asmspec, table[i].name))
943 *pnregs = table[i].nregs;
944 return table[i].number;
947 #endif /* OVERLAPPING_REGISTER_NAMES */
949 #ifdef ADDITIONAL_REGISTER_NAMES
951 static const struct { const char *const name; const int number; } table[]
952 = ADDITIONAL_REGISTER_NAMES;
954 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
955 if (table[i].name[0]
956 && ! strcmp (asmspec, table[i].name)
957 && reg_names[table[i].number][0])
958 return table[i].number;
960 #endif /* ADDITIONAL_REGISTER_NAMES */
962 if (!strcmp (asmspec, "memory"))
963 return -4;
965 if (!strcmp (asmspec, "cc"))
966 return -3;
968 return -2;
971 return -1;
975 decode_reg_name (const char *name)
977 int count;
978 return decode_reg_name_and_count (name, &count);
982 /* Return true if DECL's initializer is suitable for a BSS section. */
984 bool
985 bss_initializer_p (const_tree decl)
987 /* Do not put non-common constants into the .bss section, they belong in
988 a readonly section. */
989 return ((!TREE_READONLY (decl) || DECL_COMMON (decl))
990 && (DECL_INITIAL (decl) == NULL
991 /* In LTO we have no errors in program; error_mark_node is used
992 to mark offlined constructors. */
993 || (DECL_INITIAL (decl) == error_mark_node
994 && !in_lto_p)
995 || (flag_zero_initialized_in_bss
996 && initializer_zerop (DECL_INITIAL (decl)))));
999 /* Compute the alignment of variable specified by DECL.
1000 DONT_OUTPUT_DATA is from assemble_variable. */
1002 void
1003 align_variable (tree decl, bool dont_output_data)
1005 unsigned int align = DECL_ALIGN (decl);
1007 /* In the case for initialing an array whose length isn't specified,
1008 where we have not yet been able to do the layout,
1009 figure out the proper alignment now. */
1010 if (dont_output_data && DECL_SIZE (decl) == 0
1011 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
1012 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
1014 /* Some object file formats have a maximum alignment which they support.
1015 In particular, a.out format supports a maximum alignment of 4. */
1016 if (align > MAX_OFILE_ALIGNMENT)
1018 error ("alignment of %q+D is greater than maximum object "
1019 "file alignment %d", decl,
1020 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
1021 align = MAX_OFILE_ALIGNMENT;
1024 if (! DECL_USER_ALIGN (decl))
1026 #ifdef DATA_ABI_ALIGNMENT
1027 unsigned int data_abi_align
1028 = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1029 /* For backwards compatibility, don't assume the ABI alignment for
1030 TLS variables. */
1031 if (! DECL_THREAD_LOCAL_P (decl) || data_abi_align <= BITS_PER_WORD)
1032 align = data_abi_align;
1033 #endif
1035 /* On some machines, it is good to increase alignment sometimes.
1036 But as DECL_ALIGN is used both for actually emitting the variable
1037 and for code accessing the variable as guaranteed alignment, we
1038 can only increase the alignment if it is a performance optimization
1039 if the references to it must bind to the current definition. */
1040 if (decl_binds_to_current_def_p (decl)
1041 && !DECL_VIRTUAL_P (decl))
1043 #ifdef DATA_ALIGNMENT
1044 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1045 /* Don't increase alignment too much for TLS variables - TLS space
1046 is too precious. */
1047 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1048 align = data_align;
1049 #endif
1050 if (DECL_INITIAL (decl) != 0
1051 /* In LTO we have no errors in program; error_mark_node is used
1052 to mark offlined constructors. */
1053 && (in_lto_p || DECL_INITIAL (decl) != error_mark_node))
1055 unsigned int const_align
1056 = targetm.constant_alignment (DECL_INITIAL (decl), align);
1057 /* Don't increase alignment too much for TLS variables - TLS
1058 space is too precious. */
1059 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1060 align = const_align;
1065 /* Reset the alignment in case we have made it tighter, so we can benefit
1066 from it in get_pointer_alignment. */
1067 SET_DECL_ALIGN (decl, align);
1070 /* Return DECL_ALIGN (decl), possibly increased for optimization purposes
1071 beyond what align_variable returned. */
1073 static unsigned int
1074 get_variable_align (tree decl)
1076 unsigned int align = DECL_ALIGN (decl);
1078 /* For user aligned vars or static vars align_variable already did
1079 everything. */
1080 if (DECL_USER_ALIGN (decl) || !TREE_PUBLIC (decl))
1081 return align;
1083 #ifdef DATA_ABI_ALIGNMENT
1084 if (DECL_THREAD_LOCAL_P (decl))
1085 align = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1086 #endif
1088 /* For decls that bind to the current definition, align_variable
1089 did also everything, except for not assuming ABI required alignment
1090 of TLS variables. For other vars, increase the alignment here
1091 as an optimization. */
1092 if (!decl_binds_to_current_def_p (decl))
1094 /* On some machines, it is good to increase alignment sometimes. */
1095 #ifdef DATA_ALIGNMENT
1096 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1097 /* Don't increase alignment too much for TLS variables - TLS space
1098 is too precious. */
1099 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1100 align = data_align;
1101 #endif
1102 if (DECL_INITIAL (decl) != 0
1103 /* In LTO we have no errors in program; error_mark_node is used
1104 to mark offlined constructors. */
1105 && (in_lto_p || DECL_INITIAL (decl) != error_mark_node))
1107 unsigned int const_align
1108 = targetm.constant_alignment (DECL_INITIAL (decl), align);
1109 /* Don't increase alignment too much for TLS variables - TLS space
1110 is too precious. */
1111 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1112 align = const_align;
1116 return align;
1119 /* Return the section into which the given VAR_DECL or CONST_DECL
1120 should be placed. PREFER_NOSWITCH_P is true if a noswitch
1121 section should be used wherever possible. */
1123 section *
1124 get_variable_section (tree decl, bool prefer_noswitch_p)
1126 addr_space_t as = ADDR_SPACE_GENERIC;
1127 int reloc;
1128 varpool_node *vnode = varpool_node::get (decl);
1129 if (vnode)
1131 vnode = vnode->ultimate_alias_target ();
1132 decl = vnode->decl;
1135 if (TREE_TYPE (decl) != error_mark_node)
1136 as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1138 /* We need the constructor to figure out reloc flag. */
1139 if (vnode)
1140 vnode->get_constructor ();
1142 if (DECL_COMMON (decl))
1144 /* If the decl has been given an explicit section name, or it resides
1145 in a non-generic address space, then it isn't common, and shouldn't
1146 be handled as such. */
1147 gcc_assert (DECL_SECTION_NAME (decl) == NULL
1148 && ADDR_SPACE_GENERIC_P (as));
1149 if (DECL_THREAD_LOCAL_P (decl))
1150 return tls_comm_section;
1151 else if (TREE_PUBLIC (decl) && bss_initializer_p (decl))
1152 return comm_section;
1155 if (DECL_INITIAL (decl) == error_mark_node)
1156 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1157 else if (DECL_INITIAL (decl))
1158 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1159 else
1160 reloc = 0;
1162 resolve_unique_section (decl, reloc, flag_data_sections);
1163 if (IN_NAMED_SECTION (decl))
1165 section *sect = get_named_section (decl, NULL, reloc);
1167 if ((sect->common.flags & SECTION_BSS) && !bss_initializer_p (decl))
1169 error_at (DECL_SOURCE_LOCATION (decl),
1170 "only zero initializers are allowed in section %qs",
1171 sect->named.name);
1172 DECL_INITIAL (decl) = error_mark_node;
1174 return sect;
1177 if (ADDR_SPACE_GENERIC_P (as)
1178 && !DECL_THREAD_LOCAL_P (decl)
1179 && !(prefer_noswitch_p && targetm.have_switchable_bss_sections)
1180 && bss_initializer_p (decl))
1182 if (!TREE_PUBLIC (decl)
1183 && !((flag_sanitize & SANITIZE_ADDRESS)
1184 && asan_protect_global (decl)))
1185 return lcomm_section;
1186 if (bss_noswitch_section)
1187 return bss_noswitch_section;
1190 return targetm.asm_out.select_section (decl, reloc,
1191 get_variable_align (decl));
1194 /* Return the block into which object_block DECL should be placed. */
1196 static struct object_block *
1197 get_block_for_decl (tree decl)
1199 section *sect;
1201 if (VAR_P (decl))
1203 /* The object must be defined in this translation unit. */
1204 if (DECL_EXTERNAL (decl))
1205 return NULL;
1207 /* There's no point using object blocks for something that is
1208 isolated by definition. */
1209 if (DECL_COMDAT_GROUP (decl))
1210 return NULL;
1213 /* We can only calculate block offsets if the decl has a known
1214 constant size. */
1215 if (DECL_SIZE_UNIT (decl) == NULL)
1216 return NULL;
1217 if (!tree_fits_uhwi_p (DECL_SIZE_UNIT (decl)))
1218 return NULL;
1220 /* Find out which section should contain DECL. We cannot put it into
1221 an object block if it requires a standalone definition. */
1222 if (VAR_P (decl))
1223 align_variable (decl, 0);
1224 sect = get_variable_section (decl, true);
1225 if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
1226 return NULL;
1228 return get_block_for_section (sect);
1231 /* Make sure block symbol SYMBOL is in block BLOCK. */
1233 static void
1234 change_symbol_block (rtx symbol, struct object_block *block)
1236 if (block != SYMBOL_REF_BLOCK (symbol))
1238 gcc_assert (SYMBOL_REF_BLOCK_OFFSET (symbol) < 0);
1239 SYMBOL_REF_BLOCK (symbol) = block;
1243 /* Return true if it is possible to put DECL in an object_block. */
1245 static bool
1246 use_blocks_for_decl_p (tree decl)
1248 struct symtab_node *snode;
1250 /* Only data DECLs can be placed into object blocks. */
1251 if (!VAR_P (decl) && TREE_CODE (decl) != CONST_DECL)
1252 return false;
1254 /* Detect decls created by dw2_force_const_mem. Such decls are
1255 special because DECL_INITIAL doesn't specify the decl's true value.
1256 dw2_output_indirect_constants will instead call assemble_variable
1257 with dont_output_data set to 1 and then print the contents itself. */
1258 if (DECL_INITIAL (decl) == decl)
1259 return false;
1261 /* If this decl is an alias, then we don't want to emit a
1262 definition. */
1263 if (VAR_P (decl)
1264 && (snode = symtab_node::get (decl)) != NULL
1265 && snode->alias)
1266 return false;
1268 return targetm.use_blocks_for_decl_p (decl);
1271 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS
1272 until we find an identifier that is not itself a transparent alias.
1273 Modify the alias passed to it by reference (and all aliases on the
1274 way to the ultimate target), such that they do not have to be
1275 followed again, and return the ultimate target of the alias
1276 chain. */
1278 static inline tree
1279 ultimate_transparent_alias_target (tree *alias)
1281 tree target = *alias;
1283 if (IDENTIFIER_TRANSPARENT_ALIAS (target))
1285 gcc_assert (TREE_CHAIN (target));
1286 target = ultimate_transparent_alias_target (&TREE_CHAIN (target));
1287 gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target)
1288 && ! TREE_CHAIN (target));
1289 *alias = target;
1292 return target;
1295 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
1296 have static storage duration. In other words, it should not be an
1297 automatic variable, including PARM_DECLs.
1299 There is, however, one exception: this function handles variables
1300 explicitly placed in a particular register by the user.
1302 This is never called for PARM_DECL nodes. */
1304 void
1305 make_decl_rtl (tree decl)
1307 const char *name = 0;
1308 int reg_number;
1309 tree id;
1310 rtx x;
1312 /* Check that we are not being given an automatic variable. */
1313 gcc_assert (TREE_CODE (decl) != PARM_DECL
1314 && TREE_CODE (decl) != RESULT_DECL);
1316 /* A weak alias has TREE_PUBLIC set but not the other bits. */
1317 gcc_assert (!VAR_P (decl)
1318 || TREE_STATIC (decl)
1319 || TREE_PUBLIC (decl)
1320 || DECL_EXTERNAL (decl)
1321 || DECL_REGISTER (decl));
1323 /* And that we were not given a type or a label. */
1324 gcc_assert (TREE_CODE (decl) != TYPE_DECL
1325 && TREE_CODE (decl) != LABEL_DECL);
1327 /* For a duplicate declaration, we can be called twice on the
1328 same DECL node. Don't discard the RTL already made. */
1329 if (DECL_RTL_SET_P (decl))
1331 /* If the old RTL had the wrong mode, fix the mode. */
1332 x = DECL_RTL (decl);
1333 if (GET_MODE (x) != DECL_MODE (decl))
1334 SET_DECL_RTL (decl, adjust_address_nv (x, DECL_MODE (decl), 0));
1336 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1337 return;
1339 /* ??? Another way to do this would be to maintain a hashed
1340 table of such critters. Instead of adding stuff to a DECL
1341 to give certain attributes to it, we could use an external
1342 hash map from DECL to set of attributes. */
1344 /* Let the target reassign the RTL if it wants.
1345 This is necessary, for example, when one machine specific
1346 decl attribute overrides another. */
1347 targetm.encode_section_info (decl, DECL_RTL (decl), false);
1349 /* If the symbol has a SYMBOL_REF_BLOCK field, update it based
1350 on the new decl information. */
1351 if (MEM_P (x)
1352 && GET_CODE (XEXP (x, 0)) == SYMBOL_REF
1353 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (x, 0)))
1354 change_symbol_block (XEXP (x, 0), get_block_for_decl (decl));
1356 return;
1359 /* If this variable belongs to the global constant pool, retrieve the
1360 pre-computed RTL or recompute it in LTO mode. */
1361 if (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
1363 SET_DECL_RTL (decl, output_constant_def (DECL_INITIAL (decl), 1));
1364 return;
1367 id = DECL_ASSEMBLER_NAME (decl);
1368 if (TREE_CODE (decl) == FUNCTION_DECL
1369 && cgraph_node::get (decl)
1370 && cgraph_node::get (decl)->instrumentation_clone)
1371 ultimate_transparent_alias_target (&id);
1372 name = IDENTIFIER_POINTER (id);
1374 if (name[0] != '*' && TREE_CODE (decl) != FUNCTION_DECL
1375 && DECL_REGISTER (decl))
1377 error ("register name not specified for %q+D", decl);
1379 else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1381 const char *asmspec = name+1;
1382 machine_mode mode = DECL_MODE (decl);
1383 reg_number = decode_reg_name (asmspec);
1384 /* First detect errors in declaring global registers. */
1385 if (reg_number == -1)
1386 error ("register name not specified for %q+D", decl);
1387 else if (reg_number < 0)
1388 error ("invalid register name for %q+D", decl);
1389 else if (mode == BLKmode)
1390 error ("data type of %q+D isn%'t suitable for a register",
1391 decl);
1392 else if (!in_hard_reg_set_p (accessible_reg_set, mode, reg_number))
1393 error ("the register specified for %q+D cannot be accessed"
1394 " by the current target", decl);
1395 else if (!in_hard_reg_set_p (operand_reg_set, mode, reg_number))
1396 error ("the register specified for %q+D is not general enough"
1397 " to be used as a register variable", decl);
1398 else if (!targetm.hard_regno_mode_ok (reg_number, mode))
1399 error ("register specified for %q+D isn%'t suitable for data type",
1400 decl);
1401 /* Now handle properly declared static register variables. */
1402 else
1404 int nregs;
1406 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
1408 DECL_INITIAL (decl) = 0;
1409 error ("global register variable has initial value");
1411 if (TREE_THIS_VOLATILE (decl))
1412 warning (OPT_Wvolatile_register_var,
1413 "optimization may eliminate reads and/or "
1414 "writes to register variables");
1416 /* If the user specified one of the eliminables registers here,
1417 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
1418 confused with that register and be eliminated. This usage is
1419 somewhat suspect... */
1421 SET_DECL_RTL (decl, gen_raw_REG (mode, reg_number));
1422 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
1423 REG_USERVAR_P (DECL_RTL (decl)) = 1;
1425 if (TREE_STATIC (decl))
1427 /* Make this register global, so not usable for anything
1428 else. */
1429 #ifdef ASM_DECLARE_REGISTER_GLOBAL
1430 name = IDENTIFIER_POINTER (DECL_NAME (decl));
1431 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
1432 #endif
1433 nregs = hard_regno_nregs (reg_number, mode);
1434 while (nregs > 0)
1435 globalize_reg (decl, reg_number + --nregs);
1438 /* As a register variable, it has no section. */
1439 return;
1441 /* Avoid internal errors from invalid register
1442 specifications. */
1443 SET_DECL_ASSEMBLER_NAME (decl, NULL_TREE);
1444 DECL_HARD_REGISTER (decl) = 0;
1445 /* Also avoid SSA inconsistencies by pretending this is an external
1446 decl now. */
1447 DECL_EXTERNAL (decl) = 1;
1448 return;
1450 /* Now handle ordinary static variables and functions (in memory).
1451 Also handle vars declared register invalidly. */
1452 else if (name[0] == '*')
1454 #ifdef REGISTER_PREFIX
1455 if (strlen (REGISTER_PREFIX) != 0)
1457 reg_number = decode_reg_name (name);
1458 if (reg_number >= 0 || reg_number == -3)
1459 error ("register name given for non-register variable %q+D", decl);
1461 #endif
1464 /* Specifying a section attribute on a variable forces it into a
1465 non-.bss section, and thus it cannot be common. */
1466 /* FIXME: In general this code should not be necessary because
1467 visibility pass is doing the same work. But notice_global_symbol
1468 is called early and it needs to make DECL_RTL to get the name.
1469 we take care of recomputing the DECL_RTL after visibility is changed. */
1470 if (VAR_P (decl)
1471 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl))
1472 && DECL_SECTION_NAME (decl) != NULL
1473 && DECL_INITIAL (decl) == NULL_TREE
1474 && DECL_COMMON (decl))
1475 DECL_COMMON (decl) = 0;
1477 /* Variables can't be both common and weak. */
1478 if (VAR_P (decl) && DECL_WEAK (decl))
1479 DECL_COMMON (decl) = 0;
1481 if (use_object_blocks_p () && use_blocks_for_decl_p (decl))
1482 x = create_block_symbol (name, get_block_for_decl (decl), -1);
1483 else
1485 machine_mode address_mode = Pmode;
1486 if (TREE_TYPE (decl) != error_mark_node)
1488 addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1489 address_mode = targetm.addr_space.address_mode (as);
1491 x = gen_rtx_SYMBOL_REF (address_mode, name);
1493 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
1494 SET_SYMBOL_REF_DECL (x, decl);
1496 x = gen_rtx_MEM (DECL_MODE (decl), x);
1497 if (TREE_CODE (decl) != FUNCTION_DECL)
1498 set_mem_attributes (x, decl, 1);
1499 SET_DECL_RTL (decl, x);
1501 /* Optionally set flags or add text to the name to record information
1502 such as that it is a function name.
1503 If the name is changed, the macro ASM_OUTPUT_LABELREF
1504 will have to know how to strip this information. */
1505 targetm.encode_section_info (decl, DECL_RTL (decl), true);
1508 /* Like make_decl_rtl, but inhibit creation of new alias sets when
1509 calling make_decl_rtl. Also, reset DECL_RTL before returning the
1510 rtl. */
1513 make_decl_rtl_for_debug (tree decl)
1515 unsigned int save_aliasing_flag;
1516 rtx rtl;
1518 if (DECL_RTL_SET_P (decl))
1519 return DECL_RTL (decl);
1521 /* Kludge alert! Somewhere down the call chain, make_decl_rtl will
1522 call new_alias_set. If running with -fcompare-debug, sometimes
1523 we do not want to create alias sets that will throw the alias
1524 numbers off in the comparison dumps. So... clearing
1525 flag_strict_aliasing will keep new_alias_set() from creating a
1526 new set. */
1527 save_aliasing_flag = flag_strict_aliasing;
1528 flag_strict_aliasing = 0;
1530 rtl = DECL_RTL (decl);
1531 /* Reset DECL_RTL back, as various parts of the compiler expects
1532 DECL_RTL set meaning it is actually going to be output. */
1533 SET_DECL_RTL (decl, NULL);
1535 flag_strict_aliasing = save_aliasing_flag;
1536 return rtl;
1539 /* Output a string of literal assembler code
1540 for an `asm' keyword used between functions. */
1542 void
1543 assemble_asm (tree string)
1545 const char *p;
1546 app_enable ();
1548 if (TREE_CODE (string) == ADDR_EXPR)
1549 string = TREE_OPERAND (string, 0);
1551 p = TREE_STRING_POINTER (string);
1552 fprintf (asm_out_file, "%s%s\n", p[0] == '\t' ? "" : "\t", p);
1555 /* Write the address of the entity given by SYMBOL to SEC. */
1556 void
1557 assemble_addr_to_section (rtx symbol, section *sec)
1559 switch_to_section (sec);
1560 assemble_align (POINTER_SIZE);
1561 assemble_integer (symbol, POINTER_SIZE_UNITS, POINTER_SIZE, 1);
1564 /* Return the numbered .ctors.N (if CONSTRUCTOR_P) or .dtors.N (if
1565 not) section for PRIORITY. */
1566 section *
1567 get_cdtor_priority_section (int priority, bool constructor_p)
1569 /* Buffer conservatively large enough for the full range of a 32-bit
1570 int plus the text below. */
1571 char buf[18];
1573 /* ??? This only works reliably with the GNU linker. */
1574 sprintf (buf, "%s.%.5u",
1575 constructor_p ? ".ctors" : ".dtors",
1576 /* Invert the numbering so the linker puts us in the proper
1577 order; constructors are run from right to left, and the
1578 linker sorts in increasing order. */
1579 MAX_INIT_PRIORITY - priority);
1580 return get_section (buf, SECTION_WRITE, NULL);
1583 void
1584 default_named_section_asm_out_destructor (rtx symbol, int priority)
1586 section *sec;
1588 if (priority != DEFAULT_INIT_PRIORITY)
1589 sec = get_cdtor_priority_section (priority,
1590 /*constructor_p=*/false);
1591 else
1592 sec = get_section (".dtors", SECTION_WRITE, NULL);
1594 assemble_addr_to_section (symbol, sec);
1597 #ifdef DTORS_SECTION_ASM_OP
1598 void
1599 default_dtor_section_asm_out_destructor (rtx symbol,
1600 int priority ATTRIBUTE_UNUSED)
1602 assemble_addr_to_section (symbol, dtors_section);
1604 #endif
1606 void
1607 default_named_section_asm_out_constructor (rtx symbol, int priority)
1609 section *sec;
1611 if (priority != DEFAULT_INIT_PRIORITY)
1612 sec = get_cdtor_priority_section (priority,
1613 /*constructor_p=*/true);
1614 else
1615 sec = get_section (".ctors", SECTION_WRITE, NULL);
1617 assemble_addr_to_section (symbol, sec);
1620 #ifdef CTORS_SECTION_ASM_OP
1621 void
1622 default_ctor_section_asm_out_constructor (rtx symbol,
1623 int priority ATTRIBUTE_UNUSED)
1625 assemble_addr_to_section (symbol, ctors_section);
1627 #endif
1629 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1630 a nonzero value if the constant pool should be output before the
1631 start of the function, or a zero value if the pool should output
1632 after the end of the function. The default is to put it before the
1633 start. */
1635 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1636 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1637 #endif
1639 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1640 to be output to assembler.
1641 Set first_global_object_name and weak_global_object_name as appropriate. */
1643 void
1644 notice_global_symbol (tree decl)
1646 const char **t = &first_global_object_name;
1648 if (first_global_object_name
1649 || !TREE_PUBLIC (decl)
1650 || DECL_EXTERNAL (decl)
1651 || !DECL_NAME (decl)
1652 || (VAR_P (decl) && DECL_HARD_REGISTER (decl))
1653 || (TREE_CODE (decl) != FUNCTION_DECL
1654 && (!VAR_P (decl)
1655 || (DECL_COMMON (decl)
1656 && (DECL_INITIAL (decl) == 0
1657 || DECL_INITIAL (decl) == error_mark_node)))))
1658 return;
1660 /* We win when global object is found, but it is useful to know about weak
1661 symbol as well so we can produce nicer unique names. */
1662 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl) || flag_shlib)
1663 t = &weak_global_object_name;
1665 if (!*t)
1667 tree id = DECL_ASSEMBLER_NAME (decl);
1668 ultimate_transparent_alias_target (&id);
1669 *t = ggc_strdup (targetm.strip_name_encoding (IDENTIFIER_POINTER (id)));
1673 /* If not using flag_reorder_blocks_and_partition, decide early whether the
1674 current function goes into the cold section, so that targets can use
1675 current_function_section during RTL expansion. DECL describes the
1676 function. */
1678 void
1679 decide_function_section (tree decl)
1681 first_function_block_is_cold = false;
1683 if (DECL_SECTION_NAME (decl))
1685 struct cgraph_node *node = cgraph_node::get (current_function_decl);
1686 /* Calls to function_section rely on first_function_block_is_cold
1687 being accurate. */
1688 first_function_block_is_cold = (node
1689 && node->frequency
1690 == NODE_FREQUENCY_UNLIKELY_EXECUTED);
1693 in_cold_section_p = first_function_block_is_cold;
1696 /* Get the function's name, as described by its RTL. This may be
1697 different from the DECL_NAME name used in the source file. */
1698 const char *
1699 get_fnname_from_decl (tree decl)
1701 rtx x = DECL_RTL (decl);
1702 gcc_assert (MEM_P (x));
1703 x = XEXP (x, 0);
1704 gcc_assert (GET_CODE (x) == SYMBOL_REF);
1705 return XSTR (x, 0);
1708 /* Output assembler code for the constant pool of a function and associated
1709 with defining the name of the function. DECL describes the function.
1710 NAME is the function's name. For the constant pool, we use the current
1711 constant pool data. */
1713 void
1714 assemble_start_function (tree decl, const char *fnname)
1716 int align;
1717 char tmp_label[100];
1718 bool hot_label_written = false;
1720 if (crtl->has_bb_partition)
1722 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTB", const_labelno);
1723 crtl->subsections.hot_section_label = ggc_strdup (tmp_label);
1724 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDB", const_labelno);
1725 crtl->subsections.cold_section_label = ggc_strdup (tmp_label);
1726 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTE", const_labelno);
1727 crtl->subsections.hot_section_end_label = ggc_strdup (tmp_label);
1728 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDE", const_labelno);
1729 crtl->subsections.cold_section_end_label = ggc_strdup (tmp_label);
1730 const_labelno++;
1731 cold_function_name = NULL_TREE;
1733 else
1735 crtl->subsections.hot_section_label = NULL;
1736 crtl->subsections.cold_section_label = NULL;
1737 crtl->subsections.hot_section_end_label = NULL;
1738 crtl->subsections.cold_section_end_label = NULL;
1741 /* The following code does not need preprocessing in the assembler. */
1743 app_disable ();
1745 if (CONSTANT_POOL_BEFORE_FUNCTION)
1746 output_constant_pool (fnname, decl);
1748 align = symtab_node::get (decl)->definition_alignment ();
1750 /* Make sure the not and cold text (code) sections are properly
1751 aligned. This is necessary here in the case where the function
1752 has both hot and cold sections, because we don't want to re-set
1753 the alignment when the section switch happens mid-function. */
1755 if (crtl->has_bb_partition)
1757 first_function_block_is_cold = false;
1759 switch_to_section (unlikely_text_section ());
1760 assemble_align (align);
1761 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_label);
1763 /* When the function starts with a cold section, we need to explicitly
1764 align the hot section and write out the hot section label.
1765 But if the current function is a thunk, we do not have a CFG. */
1766 if (!cfun->is_thunk
1767 && BB_PARTITION (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) == BB_COLD_PARTITION)
1769 switch_to_section (text_section);
1770 assemble_align (align);
1771 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1772 hot_label_written = true;
1773 first_function_block_is_cold = true;
1775 in_cold_section_p = first_function_block_is_cold;
1779 /* Switch to the correct text section for the start of the function. */
1781 switch_to_section (function_section (decl));
1782 if (crtl->has_bb_partition && !hot_label_written)
1783 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1785 /* Tell assembler to move to target machine's alignment for functions. */
1786 align = floor_log2 (align / BITS_PER_UNIT);
1787 if (align > 0)
1789 ASM_OUTPUT_ALIGN (asm_out_file, align);
1792 /* Handle a user-specified function alignment.
1793 Note that we still need to align to DECL_ALIGN, as above,
1794 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1795 if (! DECL_USER_ALIGN (decl)
1796 && align_functions_log > align
1797 && optimize_function_for_speed_p (cfun))
1799 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1800 int align_log = align_functions_log;
1801 #endif
1802 int max_skip = align_functions - 1;
1803 if (flag_limit_function_alignment && crtl->max_insn_address > 0
1804 && max_skip >= crtl->max_insn_address)
1805 max_skip = crtl->max_insn_address - 1;
1807 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1808 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file, align_log, max_skip);
1809 #else
1810 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1811 #endif
1814 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1815 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1816 #endif
1818 if (!DECL_IGNORED_P (decl))
1819 (*debug_hooks->begin_function) (decl);
1821 /* Make function name accessible from other files, if appropriate. */
1823 if (TREE_PUBLIC (decl)
1824 || (cgraph_node::get (decl)->instrumentation_clone
1825 && cgraph_node::get (decl)->instrumented_version
1826 && TREE_PUBLIC (cgraph_node::get (decl)->instrumented_version->decl)))
1828 notice_global_symbol (decl);
1830 globalize_decl (decl);
1832 maybe_assemble_visibility (decl);
1835 if (DECL_PRESERVE_P (decl))
1836 targetm.asm_out.mark_decl_preserved (fnname);
1838 unsigned HOST_WIDE_INT patch_area_size = function_entry_patch_area_size;
1839 unsigned HOST_WIDE_INT patch_area_entry = function_entry_patch_area_start;
1841 tree patchable_function_entry_attr
1842 = lookup_attribute ("patchable_function_entry", DECL_ATTRIBUTES (decl));
1843 if (patchable_function_entry_attr)
1845 tree pp_val = TREE_VALUE (patchable_function_entry_attr);
1846 tree patchable_function_entry_value1 = TREE_VALUE (pp_val);
1848 if (tree_fits_uhwi_p (patchable_function_entry_value1))
1849 patch_area_size = tree_to_uhwi (patchable_function_entry_value1);
1850 else
1851 gcc_unreachable ();
1853 patch_area_entry = 0;
1854 if (list_length (pp_val) > 1)
1856 tree patchable_function_entry_value2 =
1857 TREE_VALUE (TREE_CHAIN (pp_val));
1859 if (tree_fits_uhwi_p (patchable_function_entry_value2))
1860 patch_area_entry = tree_to_uhwi (patchable_function_entry_value2);
1861 else
1862 gcc_unreachable ();
1866 if (patch_area_entry > patch_area_size)
1868 if (patch_area_size > 0)
1869 warning (OPT_Wattributes, "Patchable function entry > size");
1870 patch_area_entry = 0;
1873 /* Emit the patching area before the entry label, if any. */
1874 if (patch_area_entry > 0)
1875 targetm.asm_out.print_patchable_function_entry (asm_out_file,
1876 patch_area_entry, true);
1878 /* Do any machine/system dependent processing of the function name. */
1879 #ifdef ASM_DECLARE_FUNCTION_NAME
1880 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1881 #else
1882 /* Standard thing is just output label for the function. */
1883 ASM_OUTPUT_FUNCTION_LABEL (asm_out_file, fnname, current_function_decl);
1884 #endif /* ASM_DECLARE_FUNCTION_NAME */
1886 /* And the area after the label. Record it if we haven't done so yet. */
1887 if (patch_area_size > patch_area_entry)
1888 targetm.asm_out.print_patchable_function_entry (asm_out_file,
1889 patch_area_size-patch_area_entry,
1890 patch_area_entry == 0);
1892 if (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (decl)))
1893 saw_no_split_stack = true;
1896 /* Output assembler code associated with defining the size of the
1897 function. DECL describes the function. NAME is the function's name. */
1899 void
1900 assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED)
1902 #ifdef ASM_DECLARE_FUNCTION_SIZE
1903 /* We could have switched section in the middle of the function. */
1904 if (crtl->has_bb_partition)
1905 switch_to_section (function_section (decl));
1906 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1907 #endif
1908 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1910 output_constant_pool (fnname, decl);
1911 switch_to_section (function_section (decl)); /* need to switch back */
1913 /* Output labels for end of hot/cold text sections (to be used by
1914 debug info.) */
1915 if (crtl->has_bb_partition)
1917 section *save_text_section;
1919 save_text_section = in_section;
1920 switch_to_section (unlikely_text_section ());
1921 #ifdef ASM_DECLARE_COLD_FUNCTION_SIZE
1922 if (cold_function_name != NULL_TREE)
1923 ASM_DECLARE_COLD_FUNCTION_SIZE (asm_out_file,
1924 IDENTIFIER_POINTER (cold_function_name),
1925 decl);
1926 #endif
1927 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label);
1928 if (first_function_block_is_cold)
1929 switch_to_section (text_section);
1930 else
1931 switch_to_section (function_section (decl));
1932 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label);
1933 switch_to_section (save_text_section);
1937 /* Assemble code to leave SIZE bytes of zeros. */
1939 void
1940 assemble_zeros (unsigned HOST_WIDE_INT size)
1942 /* Do no output if -fsyntax-only. */
1943 if (flag_syntax_only)
1944 return;
1946 #ifdef ASM_NO_SKIP_IN_TEXT
1947 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1948 so we must output 0s explicitly in the text section. */
1949 if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0)
1951 unsigned HOST_WIDE_INT i;
1952 for (i = 0; i < size; i++)
1953 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1955 else
1956 #endif
1957 if (size > 0)
1958 ASM_OUTPUT_SKIP (asm_out_file, size);
1961 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1963 void
1964 assemble_align (int align)
1966 if (align > BITS_PER_UNIT)
1968 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1972 /* Assemble a string constant with the specified C string as contents. */
1974 void
1975 assemble_string (const char *p, int size)
1977 int pos = 0;
1978 int maximum = 2000;
1980 /* If the string is very long, split it up. */
1982 while (pos < size)
1984 int thissize = size - pos;
1985 if (thissize > maximum)
1986 thissize = maximum;
1988 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1990 pos += thissize;
1991 p += thissize;
1996 /* A noswitch_section_callback for lcomm_section. */
1998 static bool
1999 emit_local (tree decl ATTRIBUTE_UNUSED,
2000 const char *name ATTRIBUTE_UNUSED,
2001 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2002 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2004 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
2005 unsigned int align = symtab_node::get (decl)->definition_alignment ();
2006 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name,
2007 size, align);
2008 return true;
2009 #elif defined ASM_OUTPUT_ALIGNED_LOCAL
2010 unsigned int align = symtab_node::get (decl)->definition_alignment ();
2011 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, align);
2012 return true;
2013 #else
2014 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2015 return false;
2016 #endif
2019 /* A noswitch_section_callback for bss_noswitch_section. */
2021 #if defined ASM_OUTPUT_ALIGNED_BSS
2022 static bool
2023 emit_bss (tree decl ATTRIBUTE_UNUSED,
2024 const char *name ATTRIBUTE_UNUSED,
2025 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2026 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2028 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size,
2029 get_variable_align (decl));
2030 return true;
2032 #endif
2034 /* A noswitch_section_callback for comm_section. */
2036 static bool
2037 emit_common (tree decl ATTRIBUTE_UNUSED,
2038 const char *name ATTRIBUTE_UNUSED,
2039 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2040 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2042 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
2043 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name,
2044 size, get_variable_align (decl));
2045 return true;
2046 #elif defined ASM_OUTPUT_ALIGNED_COMMON
2047 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size,
2048 get_variable_align (decl));
2049 return true;
2050 #else
2051 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
2052 return false;
2053 #endif
2056 /* A noswitch_section_callback for tls_comm_section. */
2058 static bool
2059 emit_tls_common (tree decl ATTRIBUTE_UNUSED,
2060 const char *name ATTRIBUTE_UNUSED,
2061 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2062 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2064 #ifdef ASM_OUTPUT_TLS_COMMON
2065 ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size);
2066 return true;
2067 #else
2068 sorry ("thread-local COMMON data not implemented");
2069 return true;
2070 #endif
2073 /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT.
2074 NAME is the name of DECL's SYMBOL_REF. */
2076 static void
2077 assemble_noswitch_variable (tree decl, const char *name, section *sect,
2078 unsigned int align)
2080 unsigned HOST_WIDE_INT size, rounded;
2082 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2083 rounded = size;
2085 if ((flag_sanitize & SANITIZE_ADDRESS) && asan_protect_global (decl))
2086 size += asan_red_zone_size (size);
2088 /* Don't allocate zero bytes of common,
2089 since that means "undefined external" in the linker. */
2090 if (size == 0)
2091 rounded = 1;
2093 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2094 so that each uninitialized object starts on such a boundary. */
2095 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
2096 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2097 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2099 if (!sect->noswitch.callback (decl, name, size, rounded)
2100 && (unsigned HOST_WIDE_INT) (align / BITS_PER_UNIT) > rounded)
2101 error ("requested alignment for %q+D is greater than "
2102 "implemented alignment of %wu", decl, rounded);
2105 /* A subroutine of assemble_variable. Output the label and contents of
2106 DECL, whose address is a SYMBOL_REF with name NAME. DONT_OUTPUT_DATA
2107 is as for assemble_variable. */
2109 static void
2110 assemble_variable_contents (tree decl, const char *name,
2111 bool dont_output_data)
2113 /* Do any machine/system dependent processing of the object. */
2114 #ifdef ASM_DECLARE_OBJECT_NAME
2115 last_assemble_variable_decl = decl;
2116 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
2117 #else
2118 /* Standard thing is just output label for the object. */
2119 ASM_OUTPUT_LABEL (asm_out_file, name);
2120 #endif /* ASM_DECLARE_OBJECT_NAME */
2122 if (!dont_output_data)
2124 /* Caller is supposed to use varpool_get_constructor when it wants
2125 to output the body. */
2126 gcc_assert (!in_lto_p || DECL_INITIAL (decl) != error_mark_node);
2127 if (DECL_INITIAL (decl)
2128 && DECL_INITIAL (decl) != error_mark_node
2129 && !initializer_zerop (DECL_INITIAL (decl)))
2130 /* Output the actual data. */
2131 output_constant (DECL_INITIAL (decl),
2132 tree_to_uhwi (DECL_SIZE_UNIT (decl)),
2133 get_variable_align (decl),
2134 false);
2135 else
2136 /* Leave space for it. */
2137 assemble_zeros (tree_to_uhwi (DECL_SIZE_UNIT (decl)));
2138 targetm.asm_out.decl_end ();
2142 /* Write out assembly for the variable DECL, which is not defined in
2143 the current translation unit. */
2144 void
2145 assemble_undefined_decl (tree decl)
2147 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
2148 targetm.asm_out.assemble_undefined_decl (asm_out_file, name, decl);
2151 /* Assemble everything that is needed for a variable or function declaration.
2152 Not used for automatic variables, and not used for function definitions.
2153 Should not be called for variables of incomplete structure type.
2155 TOP_LEVEL is nonzero if this variable has file scope.
2156 AT_END is nonzero if this is the special handling, at end of compilation,
2157 to define things that have had only tentative definitions.
2158 DONT_OUTPUT_DATA if nonzero means don't actually output the
2159 initial value (that will be done by the caller). */
2161 void
2162 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
2163 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
2165 const char *name;
2166 rtx decl_rtl, symbol;
2167 section *sect;
2168 unsigned int align;
2169 bool asan_protected = false;
2171 /* This function is supposed to handle VARIABLES. Ensure we have one. */
2172 gcc_assert (VAR_P (decl));
2174 /* Emulated TLS had better not get this far. */
2175 gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl));
2177 last_assemble_variable_decl = 0;
2179 /* Normally no need to say anything here for external references,
2180 since assemble_external is called by the language-specific code
2181 when a declaration is first seen. */
2183 if (DECL_EXTERNAL (decl))
2184 return;
2186 /* Do nothing for global register variables. */
2187 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
2189 TREE_ASM_WRITTEN (decl) = 1;
2190 return;
2193 /* If type was incomplete when the variable was declared,
2194 see if it is complete now. */
2196 if (DECL_SIZE (decl) == 0)
2197 layout_decl (decl, 0);
2199 /* Still incomplete => don't allocate it; treat the tentative defn
2200 (which is what it must have been) as an `extern' reference. */
2202 if (!dont_output_data && DECL_SIZE (decl) == 0)
2204 error ("storage size of %q+D isn%'t known", decl);
2205 TREE_ASM_WRITTEN (decl) = 1;
2206 return;
2209 /* The first declaration of a variable that comes through this function
2210 decides whether it is global (in C, has external linkage)
2211 or local (in C, has internal linkage). So do nothing more
2212 if this function has already run. */
2214 if (TREE_ASM_WRITTEN (decl))
2215 return;
2217 /* Make sure targetm.encode_section_info is invoked before we set
2218 ASM_WRITTEN. */
2219 decl_rtl = DECL_RTL (decl);
2221 TREE_ASM_WRITTEN (decl) = 1;
2223 /* Do no output if -fsyntax-only. */
2224 if (flag_syntax_only)
2225 return;
2227 if (! dont_output_data
2228 && ! valid_constant_size_p (DECL_SIZE_UNIT (decl)))
2230 error ("size of variable %q+D is too large", decl);
2231 return;
2234 gcc_assert (MEM_P (decl_rtl));
2235 gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF);
2236 symbol = XEXP (decl_rtl, 0);
2238 /* If this symbol belongs to the tree constant pool, output the constant
2239 if it hasn't already been written. */
2240 if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
2242 tree decl = SYMBOL_REF_DECL (symbol);
2243 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
2244 output_constant_def_contents (symbol);
2245 return;
2248 app_disable ();
2250 name = XSTR (symbol, 0);
2251 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
2252 notice_global_symbol (decl);
2254 /* Compute the alignment of this data. */
2256 align_variable (decl, dont_output_data);
2258 if ((flag_sanitize & SANITIZE_ADDRESS)
2259 && asan_protect_global (decl))
2261 asan_protected = true;
2262 SET_DECL_ALIGN (decl, MAX (DECL_ALIGN (decl),
2263 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT));
2266 set_mem_align (decl_rtl, DECL_ALIGN (decl));
2268 align = get_variable_align (decl);
2270 if (TREE_PUBLIC (decl))
2271 maybe_assemble_visibility (decl);
2273 if (DECL_PRESERVE_P (decl))
2274 targetm.asm_out.mark_decl_preserved (name);
2276 /* First make the assembler name(s) global if appropriate. */
2277 sect = get_variable_section (decl, false);
2278 if (TREE_PUBLIC (decl)
2279 && (sect->common.flags & SECTION_COMMON) == 0)
2280 globalize_decl (decl);
2282 /* Output any data that we will need to use the address of. */
2283 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
2284 output_addressed_constants (DECL_INITIAL (decl));
2286 /* dbxout.c needs to know this. */
2287 if (sect && (sect->common.flags & SECTION_CODE) != 0)
2288 DECL_IN_TEXT_SECTION (decl) = 1;
2290 /* If the decl is part of an object_block, make sure that the decl
2291 has been positioned within its block, but do not write out its
2292 definition yet. output_object_blocks will do that later. */
2293 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
2295 gcc_assert (!dont_output_data);
2296 place_block_symbol (symbol);
2298 else if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
2299 assemble_noswitch_variable (decl, name, sect, align);
2300 else
2302 /* Special-case handling of vtv comdat sections. */
2303 if (sect->named.name
2304 && (strcmp (sect->named.name, ".vtable_map_vars") == 0))
2305 handle_vtv_comdat_section (sect, decl);
2306 else
2307 switch_to_section (sect);
2308 if (align > BITS_PER_UNIT)
2309 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2310 assemble_variable_contents (decl, name, dont_output_data);
2311 if (asan_protected)
2313 unsigned HOST_WIDE_INT int size
2314 = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2315 assemble_zeros (asan_red_zone_size (size));
2321 /* Given a function declaration (FN_DECL), this function assembles the
2322 function into the .preinit_array section. */
2324 void
2325 assemble_vtv_preinit_initializer (tree fn_decl)
2327 section *sect;
2328 unsigned flags = SECTION_WRITE;
2329 rtx symbol = XEXP (DECL_RTL (fn_decl), 0);
2331 flags |= SECTION_NOTYPE;
2332 sect = get_section (".preinit_array", flags, fn_decl);
2333 switch_to_section (sect);
2334 assemble_addr_to_section (symbol, sect);
2337 /* Return 1 if type TYPE contains any pointers. */
2339 static int
2340 contains_pointers_p (tree type)
2342 switch (TREE_CODE (type))
2344 case POINTER_TYPE:
2345 case REFERENCE_TYPE:
2346 /* I'm not sure whether OFFSET_TYPE needs this treatment,
2347 so I'll play safe and return 1. */
2348 case OFFSET_TYPE:
2349 return 1;
2351 case RECORD_TYPE:
2352 case UNION_TYPE:
2353 case QUAL_UNION_TYPE:
2355 tree fields;
2356 /* For a type that has fields, see if the fields have pointers. */
2357 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2358 if (TREE_CODE (fields) == FIELD_DECL
2359 && contains_pointers_p (TREE_TYPE (fields)))
2360 return 1;
2361 return 0;
2364 case ARRAY_TYPE:
2365 /* An array type contains pointers if its element type does. */
2366 return contains_pointers_p (TREE_TYPE (type));
2368 default:
2369 return 0;
2373 /* We delay assemble_external processing until
2374 the compilation unit is finalized. This is the best we can do for
2375 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2376 it all the way to final. See PR 17982 for further discussion. */
2377 static GTY(()) tree pending_assemble_externals;
2379 #ifdef ASM_OUTPUT_EXTERNAL
2380 /* Some targets delay some output to final using TARGET_ASM_FILE_END.
2381 As a result, assemble_external can be called after the list of externals
2382 is processed and the pointer set destroyed. */
2383 static bool pending_assemble_externals_processed;
2385 /* Avoid O(external_decls**2) lookups in the pending_assemble_externals
2386 TREE_LIST in assemble_external. */
2387 static hash_set<tree> *pending_assemble_externals_set;
2389 /* True if DECL is a function decl for which no out-of-line copy exists.
2390 It is assumed that DECL's assembler name has been set. */
2392 static bool
2393 incorporeal_function_p (tree decl)
2395 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
2397 const char *name;
2399 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2400 && ALLOCA_FUNCTION_CODE_P (DECL_FUNCTION_CODE (decl)))
2401 return true;
2403 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2404 /* Atomic or sync builtins which have survived this far will be
2405 resolved externally and therefore are not incorporeal. */
2406 if (strncmp (name, "__builtin_", 10) == 0)
2407 return true;
2409 return false;
2412 /* Actually do the tests to determine if this is necessary, and invoke
2413 ASM_OUTPUT_EXTERNAL. */
2414 static void
2415 assemble_external_real (tree decl)
2417 rtx rtl = DECL_RTL (decl);
2419 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2420 && !SYMBOL_REF_USED (XEXP (rtl, 0))
2421 && !incorporeal_function_p (decl))
2423 /* Some systems do require some output. */
2424 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2425 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2428 #endif
2430 void
2431 process_pending_assemble_externals (void)
2433 #ifdef ASM_OUTPUT_EXTERNAL
2434 tree list;
2435 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2436 assemble_external_real (TREE_VALUE (list));
2438 pending_assemble_externals = 0;
2439 pending_assemble_externals_processed = true;
2440 delete pending_assemble_externals_set;
2441 #endif
2444 /* This TREE_LIST contains any weak symbol declarations waiting
2445 to be emitted. */
2446 static GTY(()) tree weak_decls;
2448 /* Output something to declare an external symbol to the assembler,
2449 and qualifiers such as weakness. (Most assemblers don't need
2450 extern declaration, so we normally output nothing.) Do nothing if
2451 DECL is not external. */
2453 void
2454 assemble_external (tree decl ATTRIBUTE_UNUSED)
2456 /* Make sure that the ASM_OUT_FILE is open.
2457 If it's not, we should not be calling this function. */
2458 gcc_assert (asm_out_file);
2460 /* In a perfect world, the following condition would be true.
2461 Sadly, the Go front end emit assembly *from the front end*,
2462 bypassing the call graph. See PR52739. Fix before GCC 4.8. */
2463 #if 0
2464 /* This function should only be called if we are expanding, or have
2465 expanded, to RTL.
2466 Ideally, only final.c would be calling this function, but it is
2467 not clear whether that would break things somehow. See PR 17982
2468 for further discussion. */
2469 gcc_assert (state == EXPANSION
2470 || state == FINISHED);
2471 #endif
2473 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2474 return;
2476 /* We want to output annotation for weak and external symbols at
2477 very last to check if they are references or not. */
2479 if (TARGET_SUPPORTS_WEAK
2480 && DECL_WEAK (decl)
2481 /* TREE_STATIC is a weird and abused creature which is not
2482 generally the right test for whether an entity has been
2483 locally emitted, inlined or otherwise not-really-extern, but
2484 for declarations that can be weak, it happens to be
2485 match. */
2486 && !TREE_STATIC (decl)
2487 && lookup_attribute ("weak", DECL_ATTRIBUTES (decl))
2488 && value_member (decl, weak_decls) == NULL_TREE)
2489 weak_decls = tree_cons (NULL, decl, weak_decls);
2491 #ifdef ASM_OUTPUT_EXTERNAL
2492 if (pending_assemble_externals_processed)
2494 assemble_external_real (decl);
2495 return;
2498 if (! pending_assemble_externals_set->add (decl))
2499 pending_assemble_externals = tree_cons (NULL, decl,
2500 pending_assemble_externals);
2501 #endif
2504 /* Similar, for calling a library function FUN. */
2506 void
2507 assemble_external_libcall (rtx fun)
2509 /* Declare library function name external when first used, if nec. */
2510 if (! SYMBOL_REF_USED (fun))
2512 SYMBOL_REF_USED (fun) = 1;
2513 targetm.asm_out.external_libcall (fun);
2517 /* Assemble a label named NAME. */
2519 void
2520 assemble_label (FILE *file, const char *name)
2522 ASM_OUTPUT_LABEL (file, name);
2525 /* Set the symbol_referenced flag for ID. */
2526 void
2527 mark_referenced (tree id)
2529 TREE_SYMBOL_REFERENCED (id) = 1;
2532 /* Set the symbol_referenced flag for DECL and notify callgraph. */
2533 void
2534 mark_decl_referenced (tree decl)
2536 if (TREE_CODE (decl) == FUNCTION_DECL)
2538 /* Extern inline functions don't become needed when referenced.
2539 If we know a method will be emitted in other TU and no new
2540 functions can be marked reachable, just use the external
2541 definition. */
2542 struct cgraph_node *node = cgraph_node::get_create (decl);
2543 if (!DECL_EXTERNAL (decl)
2544 && !node->definition)
2545 node->mark_force_output ();
2547 else if (VAR_P (decl))
2549 varpool_node *node = varpool_node::get_create (decl);
2550 /* C++ frontend use mark_decl_references to force COMDAT variables
2551 to be output that might appear dead otherwise. */
2552 node->force_output = true;
2554 /* else do nothing - we can get various sorts of CST nodes here,
2555 which do not need to be marked. */
2559 /* Output to FILE (an assembly file) a reference to NAME. If NAME
2560 starts with a *, the rest of NAME is output verbatim. Otherwise
2561 NAME is transformed in a target-specific way (usually by the
2562 addition of an underscore). */
2564 void
2565 assemble_name_raw (FILE *file, const char *name)
2567 if (name[0] == '*')
2568 fputs (&name[1], file);
2569 else
2570 ASM_OUTPUT_LABELREF (file, name);
2573 /* Like assemble_name_raw, but should be used when NAME might refer to
2574 an entity that is also represented as a tree (like a function or
2575 variable). If NAME does refer to such an entity, that entity will
2576 be marked as referenced. */
2578 void
2579 assemble_name (FILE *file, const char *name)
2581 const char *real_name;
2582 tree id;
2584 real_name = targetm.strip_name_encoding (name);
2586 id = maybe_get_identifier (real_name);
2587 if (id)
2589 tree id_orig = id;
2591 mark_referenced (id);
2592 ultimate_transparent_alias_target (&id);
2593 if (id != id_orig)
2594 name = IDENTIFIER_POINTER (id);
2595 gcc_assert (! TREE_CHAIN (id));
2598 assemble_name_raw (file, name);
2601 /* Allocate SIZE bytes writable static space with a gensym name
2602 and return an RTX to refer to its address. */
2605 assemble_static_space (unsigned HOST_WIDE_INT size)
2607 char name[17];
2608 const char *namestring;
2609 rtx x;
2611 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2612 ++const_labelno;
2613 namestring = ggc_strdup (name);
2615 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2616 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2618 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2619 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2620 BIGGEST_ALIGNMENT);
2621 #else
2622 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2623 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2624 #else
2626 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2627 so that each uninitialized object starts on such a boundary. */
2628 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2629 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2630 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2631 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2632 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2633 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2635 #endif
2636 #endif
2637 return x;
2640 /* Assemble the static constant template for function entry trampolines.
2641 This is done at most once per compilation.
2642 Returns an RTX for the address of the template. */
2644 static GTY(()) rtx initial_trampoline;
2647 assemble_trampoline_template (void)
2649 char label[256];
2650 const char *name;
2651 int align;
2652 rtx symbol;
2654 gcc_assert (targetm.asm_out.trampoline_template != NULL);
2656 if (initial_trampoline)
2657 return initial_trampoline;
2659 /* By default, put trampoline templates in read-only data section. */
2661 #ifdef TRAMPOLINE_SECTION
2662 switch_to_section (TRAMPOLINE_SECTION);
2663 #else
2664 switch_to_section (readonly_data_section);
2665 #endif
2667 /* Write the assembler code to define one. */
2668 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2669 if (align > 0)
2670 ASM_OUTPUT_ALIGN (asm_out_file, align);
2672 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2673 targetm.asm_out.trampoline_template (asm_out_file);
2675 /* Record the rtl to refer to it. */
2676 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2677 name = ggc_strdup (label);
2678 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2679 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2681 initial_trampoline = gen_const_mem (BLKmode, symbol);
2682 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2683 set_mem_size (initial_trampoline, TRAMPOLINE_SIZE);
2685 return initial_trampoline;
2688 /* A and B are either alignments or offsets. Return the minimum alignment
2689 that may be assumed after adding the two together. */
2691 static inline unsigned
2692 min_align (unsigned int a, unsigned int b)
2694 return least_bit_hwi (a | b);
2697 /* Return the assembler directive for creating a given kind of integer
2698 object. SIZE is the number of bytes in the object and ALIGNED_P
2699 indicates whether it is known to be aligned. Return NULL if the
2700 assembly dialect has no such directive.
2702 The returned string should be printed at the start of a new line and
2703 be followed immediately by the object's initial value. */
2705 const char *
2706 integer_asm_op (int size, int aligned_p)
2708 struct asm_int_op *ops;
2710 if (aligned_p)
2711 ops = &targetm.asm_out.aligned_op;
2712 else
2713 ops = &targetm.asm_out.unaligned_op;
2715 switch (size)
2717 case 1:
2718 return targetm.asm_out.byte_op;
2719 case 2:
2720 return ops->hi;
2721 case 4:
2722 return ops->si;
2723 case 8:
2724 return ops->di;
2725 case 16:
2726 return ops->ti;
2727 default:
2728 return NULL;
2732 /* Use directive OP to assemble an integer object X. Print OP at the
2733 start of the line, followed immediately by the value of X. */
2735 void
2736 assemble_integer_with_op (const char *op, rtx x)
2738 fputs (op, asm_out_file);
2739 output_addr_const (asm_out_file, x);
2740 fputc ('\n', asm_out_file);
2743 /* The default implementation of the asm_out.integer target hook. */
2745 bool
2746 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2747 unsigned int size ATTRIBUTE_UNUSED,
2748 int aligned_p ATTRIBUTE_UNUSED)
2750 const char *op = integer_asm_op (size, aligned_p);
2751 /* Avoid GAS bugs for large values. Specifically negative values whose
2752 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2753 if (size > UNITS_PER_WORD && size > POINTER_SIZE_UNITS)
2754 return false;
2755 return op && (assemble_integer_with_op (op, x), true);
2758 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2759 the alignment of the integer in bits. Return 1 if we were able to output
2760 the constant, otherwise 0. We must be able to output the constant,
2761 if FORCE is nonzero. */
2763 bool
2764 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2766 int aligned_p;
2768 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2770 /* See if the target hook can handle this kind of object. */
2771 if (targetm.asm_out.integer (x, size, aligned_p))
2772 return true;
2774 /* If the object is a multi-byte one, try splitting it up. Split
2775 it into words it if is multi-word, otherwise split it into bytes. */
2776 if (size > 1)
2778 machine_mode omode, imode;
2779 unsigned int subalign;
2780 unsigned int subsize, i;
2781 enum mode_class mclass;
2783 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2784 subalign = MIN (align, subsize * BITS_PER_UNIT);
2785 if (GET_CODE (x) == CONST_FIXED)
2786 mclass = GET_MODE_CLASS (GET_MODE (x));
2787 else
2788 mclass = MODE_INT;
2790 omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0).require ();
2791 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0).require ();
2793 for (i = 0; i < size; i += subsize)
2795 rtx partial = simplify_subreg (omode, x, imode, i);
2796 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2797 break;
2799 if (i == size)
2800 return true;
2802 /* If we've printed some of it, but not all of it, there's no going
2803 back now. */
2804 gcc_assert (!i);
2807 gcc_assert (!force);
2809 return false;
2812 /* Assemble the floating-point constant D into an object of size MODE. ALIGN
2813 is the alignment of the constant in bits. If REVERSE is true, D is output
2814 in reverse storage order. */
2816 void
2817 assemble_real (REAL_VALUE_TYPE d, scalar_float_mode mode, unsigned int align,
2818 bool reverse)
2820 long data[4] = {0, 0, 0, 0};
2821 int bitsize, nelts, nunits, units_per;
2822 rtx elt;
2824 /* This is hairy. We have a quantity of known size. real_to_target
2825 will put it into an array of *host* longs, 32 bits per element
2826 (even if long is more than 32 bits). We need to determine the
2827 number of array elements that are occupied (nelts) and the number
2828 of *target* min-addressable units that will be occupied in the
2829 object file (nunits). We cannot assume that 32 divides the
2830 mode's bitsize (size * BITS_PER_UNIT) evenly.
2832 size * BITS_PER_UNIT is used here to make sure that padding bits
2833 (which might appear at either end of the value; real_to_target
2834 will include the padding bits in its output array) are included. */
2836 nunits = GET_MODE_SIZE (mode);
2837 bitsize = nunits * BITS_PER_UNIT;
2838 nelts = CEIL (bitsize, 32);
2839 units_per = 32 / BITS_PER_UNIT;
2841 real_to_target (data, &d, mode);
2843 /* Put out the first word with the specified alignment. */
2844 if (reverse)
2845 elt = flip_storage_order (SImode, gen_int_mode (data[nelts - 1], SImode));
2846 else
2847 elt = GEN_INT (data[0]);
2848 assemble_integer (elt, MIN (nunits, units_per), align, 1);
2849 nunits -= units_per;
2851 /* Subsequent words need only 32-bit alignment. */
2852 align = min_align (align, 32);
2854 for (int i = 1; i < nelts; i++)
2856 if (reverse)
2857 elt = flip_storage_order (SImode,
2858 gen_int_mode (data[nelts - 1 - i], SImode));
2859 else
2860 elt = GEN_INT (data[i]);
2861 assemble_integer (elt, MIN (nunits, units_per), align, 1);
2862 nunits -= units_per;
2866 /* Given an expression EXP with a constant value,
2867 reduce it to the sum of an assembler symbol and an integer.
2868 Store them both in the structure *VALUE.
2869 EXP must be reducible. */
2871 struct addr_const {
2872 rtx base;
2873 poly_int64 offset;
2876 static void
2877 decode_addr_const (tree exp, struct addr_const *value)
2879 tree target = TREE_OPERAND (exp, 0);
2880 poly_int64 offset = 0;
2881 rtx x;
2883 while (1)
2885 poly_int64 bytepos;
2886 if (TREE_CODE (target) == COMPONENT_REF
2887 && poly_int_tree_p (byte_position (TREE_OPERAND (target, 1)),
2888 &bytepos))
2890 offset += bytepos;
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
2898 += (TREE_INT_CST_LOW (TYPE_SIZE_UNIT (TREE_TYPE (target)))
2899 * wi::to_poly_widest (TREE_OPERAND (target, 1)).force_shwi ());
2900 target = TREE_OPERAND (target, 0);
2902 else if (TREE_CODE (target) == MEM_REF
2903 && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR)
2905 offset += mem_ref_offset (target).force_shwi ();
2906 target = TREE_OPERAND (TREE_OPERAND (target, 0), 0);
2908 else if (TREE_CODE (target) == INDIRECT_REF
2909 && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR
2910 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0))
2911 == ADDR_EXPR)
2912 target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0);
2913 else
2914 break;
2917 switch (TREE_CODE (target))
2919 case VAR_DECL:
2920 case FUNCTION_DECL:
2921 x = DECL_RTL (target);
2922 break;
2924 case LABEL_DECL:
2925 x = gen_rtx_MEM (FUNCTION_MODE,
2926 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2927 break;
2929 case REAL_CST:
2930 case FIXED_CST:
2931 case STRING_CST:
2932 case COMPLEX_CST:
2933 case CONSTRUCTOR:
2934 case INTEGER_CST:
2935 x = output_constant_def (target, 1);
2936 break;
2938 case INDIRECT_REF:
2939 /* This deals with absolute addresses. */
2940 offset += tree_to_shwi (TREE_OPERAND (target, 0));
2941 x = gen_rtx_MEM (QImode,
2942 gen_rtx_SYMBOL_REF (Pmode, "origin of addresses"));
2943 break;
2945 default:
2946 gcc_unreachable ();
2949 gcc_assert (MEM_P (x));
2950 x = XEXP (x, 0);
2952 value->base = x;
2953 value->offset = offset;
2956 static GTY(()) hash_table<tree_descriptor_hasher> *const_desc_htab;
2958 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2960 /* Constant pool accessor function. */
2962 hash_table<tree_descriptor_hasher> *
2963 constant_pool_htab (void)
2965 return const_desc_htab;
2968 /* Compute a hash code for a constant expression. */
2970 hashval_t
2971 tree_descriptor_hasher::hash (constant_descriptor_tree *ptr)
2973 return ptr->hash;
2976 static hashval_t
2977 const_hash_1 (const tree exp)
2979 const char *p;
2980 hashval_t hi;
2981 int len, i;
2982 enum tree_code code = TREE_CODE (exp);
2984 /* Either set P and LEN to the address and len of something to hash and
2985 exit the switch or return a value. */
2987 switch (code)
2989 case INTEGER_CST:
2990 p = (char *) &TREE_INT_CST_ELT (exp, 0);
2991 len = TREE_INT_CST_NUNITS (exp) * sizeof (HOST_WIDE_INT);
2992 break;
2994 case REAL_CST:
2995 return real_hash (TREE_REAL_CST_PTR (exp));
2997 case FIXED_CST:
2998 return fixed_hash (TREE_FIXED_CST_PTR (exp));
3000 case STRING_CST:
3001 p = TREE_STRING_POINTER (exp);
3002 len = TREE_STRING_LENGTH (exp);
3003 break;
3005 case COMPLEX_CST:
3006 return (const_hash_1 (TREE_REALPART (exp)) * 5
3007 + const_hash_1 (TREE_IMAGPART (exp)));
3009 case VECTOR_CST:
3011 hi = 7 + VECTOR_CST_NPATTERNS (exp);
3012 hi = hi * 563 + VECTOR_CST_NELTS_PER_PATTERN (exp);
3013 unsigned int count = vector_cst_encoded_nelts (exp);
3014 for (unsigned int i = 0; i < count; ++i)
3015 hi = hi * 563 + const_hash_1 (VECTOR_CST_ENCODED_ELT (exp, i));
3016 return hi;
3019 case CONSTRUCTOR:
3021 unsigned HOST_WIDE_INT idx;
3022 tree value;
3024 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
3026 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
3027 if (value)
3028 hi = hi * 603 + const_hash_1 (value);
3030 return hi;
3033 case ADDR_EXPR:
3034 case FDESC_EXPR:
3036 struct addr_const value;
3038 decode_addr_const (exp, &value);
3039 switch (GET_CODE (value.base))
3041 case SYMBOL_REF:
3042 /* Don't hash the address of the SYMBOL_REF;
3043 only use the offset and the symbol name. */
3044 hi = value.offset.coeffs[0];
3045 p = XSTR (value.base, 0);
3046 for (i = 0; p[i] != 0; i++)
3047 hi = ((hi * 613) + (unsigned) (p[i]));
3048 break;
3050 case LABEL_REF:
3051 hi = (value.offset.coeffs[0]
3052 + CODE_LABEL_NUMBER (label_ref_label (value.base)) * 13);
3053 break;
3055 default:
3056 gcc_unreachable ();
3059 return hi;
3061 case PLUS_EXPR:
3062 case POINTER_PLUS_EXPR:
3063 case MINUS_EXPR:
3064 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
3065 + const_hash_1 (TREE_OPERAND (exp, 1)));
3067 CASE_CONVERT:
3068 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
3070 default:
3071 /* A language specific constant. Just hash the code. */
3072 return code;
3075 /* Compute hashing function. */
3076 hi = len;
3077 for (i = 0; i < len; i++)
3078 hi = ((hi * 613) + (unsigned) (p[i]));
3080 return hi;
3083 /* Wrapper of compare_constant, for the htab interface. */
3084 bool
3085 tree_descriptor_hasher::equal (constant_descriptor_tree *c1,
3086 constant_descriptor_tree *c2)
3088 if (c1->hash != c2->hash)
3089 return 0;
3090 return compare_constant (c1->value, c2->value);
3093 /* Compare t1 and t2, and return 1 only if they are known to result in
3094 the same bit pattern on output. */
3096 static int
3097 compare_constant (const tree t1, const tree t2)
3099 enum tree_code typecode;
3101 if (t1 == NULL_TREE)
3102 return t2 == NULL_TREE;
3103 if (t2 == NULL_TREE)
3104 return 0;
3106 if (TREE_CODE (t1) != TREE_CODE (t2))
3107 return 0;
3109 switch (TREE_CODE (t1))
3111 case INTEGER_CST:
3112 /* Integer constants are the same only if the same width of type. */
3113 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3114 return 0;
3115 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3116 return 0;
3117 return tree_int_cst_equal (t1, t2);
3119 case REAL_CST:
3120 /* Real constants are the same only if the same width of type. In
3121 addition to the same width, we need to check whether the modes are the
3122 same. There might be two floating point modes that are the same size
3123 but have different representations, such as the PowerPC that has 2
3124 different 128-bit floating point types (IBM extended double and IEEE
3125 128-bit floating point). */
3126 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3127 return 0;
3128 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3129 return 0;
3130 return real_identical (&TREE_REAL_CST (t1), &TREE_REAL_CST (t2));
3132 case FIXED_CST:
3133 /* Fixed constants are the same only if the same width of type. */
3134 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3135 return 0;
3137 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
3139 case STRING_CST:
3140 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3141 return 0;
3143 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
3144 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
3145 TREE_STRING_LENGTH (t1)));
3147 case COMPLEX_CST:
3148 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
3149 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
3151 case VECTOR_CST:
3153 if (VECTOR_CST_NPATTERNS (t1)
3154 != VECTOR_CST_NPATTERNS (t2))
3155 return 0;
3157 if (VECTOR_CST_NELTS_PER_PATTERN (t1)
3158 != VECTOR_CST_NELTS_PER_PATTERN (t2))
3159 return 0;
3161 unsigned int count = vector_cst_encoded_nelts (t1);
3162 for (unsigned int i = 0; i < count; ++i)
3163 if (!compare_constant (VECTOR_CST_ENCODED_ELT (t1, i),
3164 VECTOR_CST_ENCODED_ELT (t2, i)))
3165 return 0;
3167 return 1;
3170 case CONSTRUCTOR:
3172 vec<constructor_elt, va_gc> *v1, *v2;
3173 unsigned HOST_WIDE_INT idx;
3175 typecode = TREE_CODE (TREE_TYPE (t1));
3176 if (typecode != TREE_CODE (TREE_TYPE (t2)))
3177 return 0;
3179 if (typecode == ARRAY_TYPE)
3181 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
3182 /* For arrays, check that mode, size and storage order match. */
3183 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
3184 || size_1 == -1
3185 || size_1 != int_size_in_bytes (TREE_TYPE (t2))
3186 || TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (t1))
3187 != TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (t2)))
3188 return 0;
3190 else
3192 /* For record and union constructors, require exact type
3193 equality. */
3194 if (TREE_TYPE (t1) != TREE_TYPE (t2))
3195 return 0;
3198 v1 = CONSTRUCTOR_ELTS (t1);
3199 v2 = CONSTRUCTOR_ELTS (t2);
3200 if (vec_safe_length (v1) != vec_safe_length (v2))
3201 return 0;
3203 for (idx = 0; idx < vec_safe_length (v1); ++idx)
3205 constructor_elt *c1 = &(*v1)[idx];
3206 constructor_elt *c2 = &(*v2)[idx];
3208 /* Check that each value is the same... */
3209 if (!compare_constant (c1->value, c2->value))
3210 return 0;
3211 /* ... and that they apply to the same fields! */
3212 if (typecode == ARRAY_TYPE)
3214 if (!compare_constant (c1->index, c2->index))
3215 return 0;
3217 else
3219 if (c1->index != c2->index)
3220 return 0;
3224 return 1;
3227 case ADDR_EXPR:
3228 case FDESC_EXPR:
3230 struct addr_const value1, value2;
3231 enum rtx_code code;
3232 int ret;
3234 decode_addr_const (t1, &value1);
3235 decode_addr_const (t2, &value2);
3237 if (maybe_ne (value1.offset, value2.offset))
3238 return 0;
3240 code = GET_CODE (value1.base);
3241 if (code != GET_CODE (value2.base))
3242 return 0;
3244 switch (code)
3246 case SYMBOL_REF:
3247 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3248 break;
3250 case LABEL_REF:
3251 ret = (CODE_LABEL_NUMBER (label_ref_label (value1.base))
3252 == CODE_LABEL_NUMBER (label_ref_label (value2.base)));
3253 break;
3255 default:
3256 gcc_unreachable ();
3258 return ret;
3261 case PLUS_EXPR:
3262 case POINTER_PLUS_EXPR:
3263 case MINUS_EXPR:
3264 case RANGE_EXPR:
3265 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3266 && compare_constant (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3268 CASE_CONVERT:
3269 case VIEW_CONVERT_EXPR:
3270 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3272 default:
3273 return 0;
3276 gcc_unreachable ();
3279 /* Return the section into which constant EXP should be placed. */
3281 static section *
3282 get_constant_section (tree exp, unsigned int align)
3284 return targetm.asm_out.select_section (exp,
3285 compute_reloc_for_constant (exp),
3286 align);
3289 /* Return the size of constant EXP in bytes. */
3291 static HOST_WIDE_INT
3292 get_constant_size (tree exp)
3294 HOST_WIDE_INT size;
3296 size = int_size_in_bytes (TREE_TYPE (exp));
3297 if (TREE_CODE (exp) == STRING_CST)
3298 size = MAX (TREE_STRING_LENGTH (exp), size);
3299 return size;
3302 /* Subroutine of output_constant_def:
3303 No constant equal to EXP is known to have been output.
3304 Make a constant descriptor to enter EXP in the hash table.
3305 Assign the label number and construct RTL to refer to the
3306 constant's location in memory.
3307 Caller is responsible for updating the hash table. */
3309 static struct constant_descriptor_tree *
3310 build_constant_desc (tree exp)
3312 struct constant_descriptor_tree *desc;
3313 rtx symbol, rtl;
3314 char label[256];
3315 int labelno;
3316 tree decl;
3318 desc = ggc_alloc<constant_descriptor_tree> ();
3319 desc->value = exp;
3321 /* Create a string containing the label name, in LABEL. */
3322 labelno = const_labelno++;
3323 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3325 /* Construct the VAR_DECL associated with the constant. */
3326 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3327 TREE_TYPE (exp));
3328 DECL_ARTIFICIAL (decl) = 1;
3329 DECL_IGNORED_P (decl) = 1;
3330 TREE_READONLY (decl) = 1;
3331 TREE_STATIC (decl) = 1;
3332 TREE_ADDRESSABLE (decl) = 1;
3333 /* We don't set the RTL yet as this would cause varpool to assume that the
3334 variable is referenced. Moreover, it would just be dropped in LTO mode.
3335 Instead we set the flag that will be recognized in make_decl_rtl. */
3336 DECL_IN_CONSTANT_POOL (decl) = 1;
3337 DECL_INITIAL (decl) = desc->value;
3338 /* ??? targetm.constant_alignment hasn't been updated for vector types on
3339 most architectures so use DATA_ALIGNMENT as well, except for strings. */
3340 if (TREE_CODE (exp) == STRING_CST)
3341 SET_DECL_ALIGN (decl, targetm.constant_alignment (exp, DECL_ALIGN (decl)));
3342 else
3343 align_variable (decl, 0);
3345 /* Now construct the SYMBOL_REF and the MEM. */
3346 if (use_object_blocks_p ())
3348 int align = (TREE_CODE (decl) == CONST_DECL
3349 || (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
3350 ? DECL_ALIGN (decl)
3351 : symtab_node::get (decl)->definition_alignment ());
3352 section *sect = get_constant_section (exp, align);
3353 symbol = create_block_symbol (ggc_strdup (label),
3354 get_block_for_section (sect), -1);
3356 else
3357 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3358 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3359 SET_SYMBOL_REF_DECL (symbol, decl);
3360 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3362 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3363 set_mem_attributes (rtl, exp, 1);
3364 set_mem_alias_set (rtl, 0);
3366 /* Putting EXP into the literal pool might have imposed a different
3367 alignment which should be visible in the RTX as well. */
3368 set_mem_align (rtl, DECL_ALIGN (decl));
3370 /* We cannot share RTX'es in pool entries.
3371 Mark this piece of RTL as required for unsharing. */
3372 RTX_FLAG (rtl, used) = 1;
3374 /* Set flags or add text to the name to record information, such as
3375 that it is a local symbol. If the name is changed, the macro
3376 ASM_OUTPUT_LABELREF will have to know how to strip this
3377 information. This call might invalidate our local variable
3378 SYMBOL; we can't use it afterward. */
3379 targetm.encode_section_info (exp, rtl, true);
3381 desc->rtl = rtl;
3383 return desc;
3386 /* Return an rtx representing a reference to constant data in memory
3387 for the constant expression EXP.
3389 If assembler code for such a constant has already been output,
3390 return an rtx to refer to it.
3391 Otherwise, output such a constant in memory
3392 and generate an rtx for it.
3394 If DEFER is nonzero, this constant can be deferred and output only
3395 if referenced in the function after all optimizations.
3397 `const_desc_table' records which constants already have label strings. */
3400 output_constant_def (tree exp, int defer)
3402 struct constant_descriptor_tree *desc;
3403 struct constant_descriptor_tree key;
3405 /* Look up EXP in the table of constant descriptors. If we didn't find
3406 it, create a new one. */
3407 key.value = exp;
3408 key.hash = const_hash_1 (exp);
3409 constant_descriptor_tree **loc
3410 = const_desc_htab->find_slot_with_hash (&key, key.hash, INSERT);
3412 desc = *loc;
3413 if (desc == 0)
3415 desc = build_constant_desc (exp);
3416 desc->hash = key.hash;
3417 *loc = desc;
3420 maybe_output_constant_def_contents (desc, defer);
3421 return desc->rtl;
3424 /* Subroutine of output_constant_def: Decide whether or not we need to
3425 output the constant DESC now, and if so, do it. */
3426 static void
3427 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3428 int defer)
3430 rtx symbol = XEXP (desc->rtl, 0);
3431 tree exp = desc->value;
3433 if (flag_syntax_only)
3434 return;
3436 if (TREE_ASM_WRITTEN (exp))
3437 /* Already output; don't do it again. */
3438 return;
3440 /* We can always defer constants as long as the context allows
3441 doing so. */
3442 if (defer)
3444 /* Increment n_deferred_constants if it exists. It needs to be at
3445 least as large as the number of constants actually referred to
3446 by the function. If it's too small we'll stop looking too early
3447 and fail to emit constants; if it's too large we'll only look
3448 through the entire function when we could have stopped earlier. */
3449 if (cfun)
3450 n_deferred_constants++;
3451 return;
3454 output_constant_def_contents (symbol);
3457 /* Subroutine of output_constant_def_contents. Output the definition
3458 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3459 constant's alignment in bits. */
3461 static void
3462 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3464 HOST_WIDE_INT size;
3466 size = get_constant_size (exp);
3468 /* Do any machine/system dependent processing of the constant. */
3469 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3471 /* Output the value of EXP. */
3472 output_constant (exp, size, align, false);
3474 targetm.asm_out.decl_end ();
3477 /* We must output the constant data referred to by SYMBOL; do so. */
3479 static void
3480 output_constant_def_contents (rtx symbol)
3482 tree decl = SYMBOL_REF_DECL (symbol);
3483 tree exp = DECL_INITIAL (decl);
3484 bool asan_protected = false;
3486 /* Make sure any other constants whose addresses appear in EXP
3487 are assigned label numbers. */
3488 output_addressed_constants (exp);
3490 /* We are no longer deferring this constant. */
3491 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3493 if ((flag_sanitize & SANITIZE_ADDRESS)
3494 && TREE_CODE (exp) == STRING_CST
3495 && asan_protect_global (exp))
3497 asan_protected = true;
3498 SET_DECL_ALIGN (decl, MAX (DECL_ALIGN (decl),
3499 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT));
3502 /* If the constant is part of an object block, make sure that the
3503 decl has been positioned within its block, but do not write out
3504 its definition yet. output_object_blocks will do that later. */
3505 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3506 place_block_symbol (symbol);
3507 else
3509 int align = (TREE_CODE (decl) == CONST_DECL
3510 || (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
3511 ? DECL_ALIGN (decl)
3512 : symtab_node::get (decl)->definition_alignment ());
3513 switch_to_section (get_constant_section (exp, align));
3514 if (align > BITS_PER_UNIT)
3515 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3516 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3517 if (asan_protected)
3519 HOST_WIDE_INT size = get_constant_size (exp);
3520 assemble_zeros (asan_red_zone_size (size));
3525 /* Look up EXP in the table of constant descriptors. Return the rtl
3526 if it has been emitted, else null. */
3529 lookup_constant_def (tree exp)
3531 struct constant_descriptor_tree key;
3533 key.value = exp;
3534 key.hash = const_hash_1 (exp);
3535 constant_descriptor_tree *desc
3536 = const_desc_htab->find_with_hash (&key, key.hash);
3538 return (desc ? desc->rtl : NULL_RTX);
3541 /* Return a tree representing a reference to constant data in memory
3542 for the constant expression EXP.
3544 This is the counterpart of output_constant_def at the Tree level. */
3546 tree
3547 tree_output_constant_def (tree exp)
3549 struct constant_descriptor_tree *desc, key;
3550 tree decl;
3552 /* Look up EXP in the table of constant descriptors. If we didn't find
3553 it, create a new one. */
3554 key.value = exp;
3555 key.hash = const_hash_1 (exp);
3556 constant_descriptor_tree **loc
3557 = const_desc_htab->find_slot_with_hash (&key, key.hash, INSERT);
3559 desc = *loc;
3560 if (desc == 0)
3562 desc = build_constant_desc (exp);
3563 desc->hash = key.hash;
3564 *loc = desc;
3567 decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3568 varpool_node::finalize_decl (decl);
3569 return decl;
3572 struct GTY((chain_next ("%h.next"), for_user)) constant_descriptor_rtx {
3573 struct constant_descriptor_rtx *next;
3574 rtx mem;
3575 rtx sym;
3576 rtx constant;
3577 HOST_WIDE_INT offset;
3578 hashval_t hash;
3579 fixed_size_mode mode;
3580 unsigned int align;
3581 int labelno;
3582 int mark;
3585 struct const_rtx_desc_hasher : ggc_ptr_hash<constant_descriptor_rtx>
3587 static hashval_t hash (constant_descriptor_rtx *);
3588 static bool equal (constant_descriptor_rtx *, constant_descriptor_rtx *);
3591 /* Used in the hash tables to avoid outputting the same constant
3592 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3593 are output once per function, not once per file. */
3594 /* ??? Only a few targets need per-function constant pools. Most
3595 can use one per-file pool. Should add a targetm bit to tell the
3596 difference. */
3598 struct GTY(()) rtx_constant_pool {
3599 /* Pointers to first and last constant in pool, as ordered by offset. */
3600 struct constant_descriptor_rtx *first;
3601 struct constant_descriptor_rtx *last;
3603 /* Hash facility for making memory-constants from constant rtl-expressions.
3604 It is used on RISC machines where immediate integer arguments and
3605 constant addresses are restricted so that such constants must be stored
3606 in memory. */
3607 hash_table<const_rtx_desc_hasher> *const_rtx_htab;
3609 /* Current offset in constant pool (does not include any
3610 machine-specific header). */
3611 HOST_WIDE_INT offset;
3614 /* Hash and compare functions for const_rtx_htab. */
3616 hashval_t
3617 const_rtx_desc_hasher::hash (constant_descriptor_rtx *desc)
3619 return desc->hash;
3622 bool
3623 const_rtx_desc_hasher::equal (constant_descriptor_rtx *x,
3624 constant_descriptor_rtx *y)
3626 if (x->mode != y->mode)
3627 return 0;
3628 return rtx_equal_p (x->constant, y->constant);
3631 /* Hash one component of a constant. */
3633 static hashval_t
3634 const_rtx_hash_1 (const_rtx x)
3636 unsigned HOST_WIDE_INT hwi;
3637 machine_mode mode;
3638 enum rtx_code code;
3639 hashval_t h;
3640 int i;
3642 code = GET_CODE (x);
3643 mode = GET_MODE (x);
3644 h = (hashval_t) code * 1048573 + mode;
3646 switch (code)
3648 case CONST_INT:
3649 hwi = INTVAL (x);
3651 fold_hwi:
3653 int shift = sizeof (hashval_t) * CHAR_BIT;
3654 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3656 h ^= (hashval_t) hwi;
3657 for (i = 1; i < n; ++i)
3659 hwi >>= shift;
3660 h ^= (hashval_t) hwi;
3663 break;
3665 case CONST_WIDE_INT:
3666 hwi = 0;
3668 for (i = 0; i < CONST_WIDE_INT_NUNITS (x); i++)
3669 hwi ^= CONST_WIDE_INT_ELT (x, i);
3670 goto fold_hwi;
3673 case CONST_DOUBLE:
3674 if (TARGET_SUPPORTS_WIDE_INT == 0 && mode == VOIDmode)
3676 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3677 goto fold_hwi;
3679 else
3680 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3681 break;
3683 case CONST_FIXED:
3684 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3685 break;
3687 case SYMBOL_REF:
3688 h ^= htab_hash_string (XSTR (x, 0));
3689 break;
3691 case LABEL_REF:
3692 h = h * 251 + CODE_LABEL_NUMBER (label_ref_label (x));
3693 break;
3695 case UNSPEC:
3696 case UNSPEC_VOLATILE:
3697 h = h * 251 + XINT (x, 1);
3698 break;
3700 default:
3701 break;
3704 return h;
3707 /* Compute a hash value for X, which should be a constant. */
3709 static hashval_t
3710 const_rtx_hash (rtx x)
3712 hashval_t h = 0;
3713 subrtx_iterator::array_type array;
3714 FOR_EACH_SUBRTX (iter, array, x, ALL)
3715 h = h * 509 + const_rtx_hash_1 (*iter);
3716 return h;
3720 /* Create and return a new rtx constant pool. */
3722 static struct rtx_constant_pool *
3723 create_constant_pool (void)
3725 struct rtx_constant_pool *pool;
3727 pool = ggc_alloc<rtx_constant_pool> ();
3728 pool->const_rtx_htab = hash_table<const_rtx_desc_hasher>::create_ggc (31);
3729 pool->first = NULL;
3730 pool->last = NULL;
3731 pool->offset = 0;
3732 return pool;
3735 /* Initialize constant pool hashing for a new function. */
3737 void
3738 init_varasm_status (void)
3740 crtl->varasm.pool = create_constant_pool ();
3741 crtl->varasm.deferred_constants = 0;
3744 /* Given a MINUS expression, simplify it if both sides
3745 include the same symbol. */
3748 simplify_subtraction (rtx x)
3750 rtx r = simplify_rtx (x);
3751 return r ? r : x;
3754 /* Given a constant rtx X, make (or find) a memory constant for its value
3755 and return a MEM rtx to refer to it in memory. IN_MODE is the mode
3756 of X. */
3759 force_const_mem (machine_mode in_mode, rtx x)
3761 struct constant_descriptor_rtx *desc, tmp;
3762 struct rtx_constant_pool *pool;
3763 char label[256];
3764 rtx def, symbol;
3765 hashval_t hash;
3766 unsigned int align;
3767 constant_descriptor_rtx **slot;
3768 fixed_size_mode mode;
3770 /* We can't force variable-sized objects to memory. */
3771 if (!is_a <fixed_size_mode> (in_mode, &mode))
3772 return NULL_RTX;
3774 /* If we're not allowed to drop X into the constant pool, don't. */
3775 if (targetm.cannot_force_const_mem (mode, x))
3776 return NULL_RTX;
3778 /* Record that this function has used a constant pool entry. */
3779 crtl->uses_const_pool = 1;
3781 /* Decide which pool to use. */
3782 pool = (targetm.use_blocks_for_constant_p (mode, x)
3783 ? shared_constant_pool
3784 : crtl->varasm.pool);
3786 /* Lookup the value in the hashtable. */
3787 tmp.constant = x;
3788 tmp.mode = mode;
3789 hash = const_rtx_hash (x);
3790 slot = pool->const_rtx_htab->find_slot_with_hash (&tmp, hash, INSERT);
3791 desc = *slot;
3793 /* If the constant was already present, return its memory. */
3794 if (desc)
3795 return copy_rtx (desc->mem);
3797 /* Otherwise, create a new descriptor. */
3798 desc = ggc_alloc<constant_descriptor_rtx> ();
3799 *slot = desc;
3801 /* Align the location counter as required by EXP's data type. */
3802 machine_mode align_mode = (mode == VOIDmode ? word_mode : mode);
3803 align = targetm.static_rtx_alignment (align_mode);
3805 pool->offset += (align / BITS_PER_UNIT) - 1;
3806 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3808 desc->next = NULL;
3809 desc->constant = copy_rtx (tmp.constant);
3810 desc->offset = pool->offset;
3811 desc->hash = hash;
3812 desc->mode = mode;
3813 desc->align = align;
3814 desc->labelno = const_labelno;
3815 desc->mark = 0;
3817 pool->offset += GET_MODE_SIZE (mode);
3818 if (pool->last)
3819 pool->last->next = desc;
3820 else
3821 pool->first = pool->last = desc;
3822 pool->last = desc;
3824 /* Create a string containing the label name, in LABEL. */
3825 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3826 ++const_labelno;
3828 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3829 the constants pool. */
3830 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3832 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3833 symbol = create_block_symbol (ggc_strdup (label),
3834 get_block_for_section (sect), -1);
3836 else
3837 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3838 desc->sym = symbol;
3839 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3840 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3841 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3843 /* Construct the MEM. */
3844 desc->mem = def = gen_const_mem (mode, symbol);
3845 set_mem_align (def, align);
3847 /* If we're dropping a label to the constant pool, make sure we
3848 don't delete it. */
3849 if (GET_CODE (x) == LABEL_REF)
3850 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3852 return copy_rtx (def);
3855 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3858 get_pool_constant (const_rtx addr)
3860 return SYMBOL_REF_CONSTANT (addr)->constant;
3863 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3864 and whether it has been output or not. */
3867 get_pool_constant_mark (rtx addr, bool *pmarked)
3869 struct constant_descriptor_rtx *desc;
3871 desc = SYMBOL_REF_CONSTANT (addr);
3872 *pmarked = (desc->mark != 0);
3873 return desc->constant;
3876 /* Similar, return the mode. */
3878 fixed_size_mode
3879 get_pool_mode (const_rtx addr)
3881 return SYMBOL_REF_CONSTANT (addr)->mode;
3884 /* Return TRUE if and only if the constant pool has no entries. Note
3885 that even entries we might end up choosing not to emit are counted
3886 here, so there is the potential for missed optimizations. */
3888 bool
3889 constant_pool_empty_p (void)
3891 return crtl->varasm.pool->first == NULL;
3894 /* Worker function for output_constant_pool_1. Emit assembly for X
3895 in MODE with known alignment ALIGN. */
3897 static void
3898 output_constant_pool_2 (fixed_size_mode mode, rtx x, unsigned int align)
3900 switch (GET_MODE_CLASS (mode))
3902 case MODE_FLOAT:
3903 case MODE_DECIMAL_FLOAT:
3905 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3906 assemble_real (*CONST_DOUBLE_REAL_VALUE (x),
3907 as_a <scalar_float_mode> (mode), align, false);
3908 break;
3911 case MODE_INT:
3912 case MODE_PARTIAL_INT:
3913 case MODE_FRACT:
3914 case MODE_UFRACT:
3915 case MODE_ACCUM:
3916 case MODE_UACCUM:
3917 case MODE_POINTER_BOUNDS:
3918 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3919 break;
3921 case MODE_VECTOR_BOOL:
3923 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3925 /* Pick the smallest integer mode that contains at least one
3926 whole element. Often this is byte_mode and contains more
3927 than one element. */
3928 unsigned int nelts = GET_MODE_NUNITS (mode);
3929 unsigned int elt_bits = GET_MODE_BITSIZE (mode) / nelts;
3930 unsigned int int_bits = MAX (elt_bits, BITS_PER_UNIT);
3931 scalar_int_mode int_mode = int_mode_for_size (int_bits, 0).require ();
3933 /* Build the constant up one integer at a time. */
3934 unsigned int elts_per_int = int_bits / elt_bits;
3935 for (unsigned int i = 0; i < nelts; i += elts_per_int)
3937 unsigned HOST_WIDE_INT value = 0;
3938 unsigned int limit = MIN (nelts - i, elts_per_int);
3939 for (unsigned int j = 0; j < limit; ++j)
3940 if (INTVAL (CONST_VECTOR_ELT (x, i + j)) != 0)
3941 value |= 1 << (j * elt_bits);
3942 output_constant_pool_2 (int_mode, gen_int_mode (value, int_mode),
3943 i != 0 ? MIN (align, int_bits) : align);
3945 break;
3947 case MODE_VECTOR_FLOAT:
3948 case MODE_VECTOR_INT:
3949 case MODE_VECTOR_FRACT:
3950 case MODE_VECTOR_UFRACT:
3951 case MODE_VECTOR_ACCUM:
3952 case MODE_VECTOR_UACCUM:
3954 int i, units;
3955 scalar_mode submode = GET_MODE_INNER (mode);
3956 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3958 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3959 units = GET_MODE_NUNITS (mode);
3961 for (i = 0; i < units; i++)
3963 rtx elt = CONST_VECTOR_ELT (x, i);
3964 output_constant_pool_2 (submode, elt, i ? subalign : align);
3967 break;
3969 default:
3970 gcc_unreachable ();
3974 /* Worker function for output_constant_pool. Emit constant DESC,
3975 giving it ALIGN bits of alignment. */
3977 static void
3978 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3979 unsigned int align)
3981 rtx x, tmp;
3983 x = desc->constant;
3985 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3986 whose CODE_LABEL has been deleted. This can occur if a jump table
3987 is eliminated by optimization. If so, write a constant of zero
3988 instead. Note that this can also happen by turning the
3989 CODE_LABEL into a NOTE. */
3990 /* ??? This seems completely and utterly wrong. Certainly it's
3991 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3992 functioning even with rtx_insn::deleted and friends. */
3994 tmp = x;
3995 switch (GET_CODE (tmp))
3997 case CONST:
3998 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3999 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
4000 break;
4001 tmp = XEXP (XEXP (tmp, 0), 0);
4002 /* FALLTHRU */
4004 case LABEL_REF:
4006 rtx_insn *insn = label_ref_label (tmp);
4007 gcc_assert (!insn->deleted ());
4008 gcc_assert (!NOTE_P (insn)
4009 || NOTE_KIND (insn) != NOTE_INSN_DELETED);
4010 break;
4013 default:
4014 break;
4017 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
4018 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
4019 align, desc->labelno, done);
4020 #endif
4022 assemble_align (align);
4024 /* Output the label. */
4025 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
4027 /* Output the data.
4028 Pass actual alignment value while emitting string constant to asm code
4029 as function 'output_constant_pool_1' explicitly passes the alignment as 1
4030 assuming that the data is already aligned which prevents the generation
4031 of fix-up table entries. */
4032 output_constant_pool_2 (desc->mode, x, desc->align);
4034 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
4035 sections have proper size. */
4036 if (align > GET_MODE_BITSIZE (desc->mode)
4037 && in_section
4038 && (in_section->common.flags & SECTION_MERGE))
4039 assemble_align (align);
4041 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
4042 done:
4043 #endif
4044 return;
4047 /* Recompute the offsets of entries in POOL, and the overall size of
4048 POOL. Do this after calling mark_constant_pool to ensure that we
4049 are computing the offset values for the pool which we will actually
4050 emit. */
4052 static void
4053 recompute_pool_offsets (struct rtx_constant_pool *pool)
4055 struct constant_descriptor_rtx *desc;
4056 pool->offset = 0;
4058 for (desc = pool->first; desc ; desc = desc->next)
4059 if (desc->mark)
4061 /* Recalculate offset. */
4062 unsigned int align = desc->align;
4063 pool->offset += (align / BITS_PER_UNIT) - 1;
4064 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
4065 desc->offset = pool->offset;
4066 pool->offset += GET_MODE_SIZE (desc->mode);
4070 /* Mark all constants that are referenced by SYMBOL_REFs in X.
4071 Emit referenced deferred strings. */
4073 static void
4074 mark_constants_in_pattern (rtx insn)
4076 subrtx_iterator::array_type array;
4077 FOR_EACH_SUBRTX (iter, array, PATTERN (insn), ALL)
4079 const_rtx x = *iter;
4080 if (GET_CODE (x) == SYMBOL_REF)
4082 if (CONSTANT_POOL_ADDRESS_P (x))
4084 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
4085 if (desc->mark == 0)
4087 desc->mark = 1;
4088 iter.substitute (desc->constant);
4091 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
4093 tree decl = SYMBOL_REF_DECL (x);
4094 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
4096 n_deferred_constants--;
4097 output_constant_def_contents (CONST_CAST_RTX (x));
4104 /* Look through appropriate parts of INSN, marking all entries in the
4105 constant pool which are actually being used. Entries that are only
4106 referenced by other constants are also marked as used. Emit
4107 deferred strings that are used. */
4109 static void
4110 mark_constants (rtx_insn *insn)
4112 if (!INSN_P (insn))
4113 return;
4115 /* Insns may appear inside a SEQUENCE. Only check the patterns of
4116 insns, not any notes that may be attached. We don't want to mark
4117 a constant just because it happens to appear in a REG_EQUIV note. */
4118 if (rtx_sequence *seq = dyn_cast <rtx_sequence *> (PATTERN (insn)))
4120 int i, n = seq->len ();
4121 for (i = 0; i < n; ++i)
4123 rtx subinsn = seq->element (i);
4124 if (INSN_P (subinsn))
4125 mark_constants_in_pattern (subinsn);
4128 else
4129 mark_constants_in_pattern (insn);
4132 /* Look through the instructions for this function, and mark all the
4133 entries in POOL which are actually being used. Emit deferred constants
4134 which have indeed been used. */
4136 static void
4137 mark_constant_pool (void)
4139 rtx_insn *insn;
4141 if (!crtl->uses_const_pool && n_deferred_constants == 0)
4142 return;
4144 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4145 mark_constants (insn);
4148 /* Write all the constants in POOL. */
4150 static void
4151 output_constant_pool_contents (struct rtx_constant_pool *pool)
4153 struct constant_descriptor_rtx *desc;
4155 for (desc = pool->first; desc ; desc = desc->next)
4156 if (desc->mark)
4158 /* If the constant is part of an object_block, make sure that
4159 the constant has been positioned within its block, but do not
4160 write out its definition yet. output_object_blocks will do
4161 that later. */
4162 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
4163 && SYMBOL_REF_BLOCK (desc->sym))
4164 place_block_symbol (desc->sym);
4165 else
4167 switch_to_section (targetm.asm_out.select_rtx_section
4168 (desc->mode, desc->constant, desc->align));
4169 output_constant_pool_1 (desc, desc->align);
4174 /* Mark all constants that are used in the current function, then write
4175 out the function's private constant pool. */
4177 static void
4178 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
4179 tree fndecl ATTRIBUTE_UNUSED)
4181 struct rtx_constant_pool *pool = crtl->varasm.pool;
4183 /* It is possible for gcc to call force_const_mem and then to later
4184 discard the instructions which refer to the constant. In such a
4185 case we do not need to output the constant. */
4186 mark_constant_pool ();
4188 /* Having marked the constant pool entries we'll actually emit, we
4189 now need to rebuild the offset information, which may have become
4190 stale. */
4191 recompute_pool_offsets (pool);
4193 #ifdef ASM_OUTPUT_POOL_PROLOGUE
4194 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
4195 #endif
4197 output_constant_pool_contents (pool);
4199 #ifdef ASM_OUTPUT_POOL_EPILOGUE
4200 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
4201 #endif
4204 /* Write the contents of the shared constant pool. */
4206 void
4207 output_shared_constant_pool (void)
4209 output_constant_pool_contents (shared_constant_pool);
4212 /* Determine what kind of relocations EXP may need. */
4215 compute_reloc_for_constant (tree exp)
4217 int reloc = 0, reloc2;
4218 tree tem;
4220 switch (TREE_CODE (exp))
4222 case ADDR_EXPR:
4223 case FDESC_EXPR:
4224 /* Go inside any operations that get_inner_reference can handle and see
4225 if what's inside is a constant: no need to do anything here for
4226 addresses of variables or functions. */
4227 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4228 tem = TREE_OPERAND (tem, 0))
4231 if (TREE_CODE (tem) == MEM_REF
4232 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4234 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4235 break;
4238 if (!targetm.binds_local_p (tem))
4239 reloc |= 2;
4240 else
4241 reloc |= 1;
4242 break;
4244 case PLUS_EXPR:
4245 case POINTER_PLUS_EXPR:
4246 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4247 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4248 break;
4250 case MINUS_EXPR:
4251 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4252 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4253 /* The difference of two local labels is computable at link time. */
4254 if (reloc == 1 && reloc2 == 1)
4255 reloc = 0;
4256 else
4257 reloc |= reloc2;
4258 break;
4260 CASE_CONVERT:
4261 case VIEW_CONVERT_EXPR:
4262 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4263 break;
4265 case CONSTRUCTOR:
4267 unsigned HOST_WIDE_INT idx;
4268 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4269 if (tem != 0)
4270 reloc |= compute_reloc_for_constant (tem);
4272 break;
4274 default:
4275 break;
4277 return reloc;
4280 /* Find all the constants whose addresses are referenced inside of EXP,
4281 and make sure assembler code with a label has been output for each one.
4282 Indicate whether an ADDR_EXPR has been encountered. */
4284 static void
4285 output_addressed_constants (tree exp)
4287 tree tem;
4289 switch (TREE_CODE (exp))
4291 case ADDR_EXPR:
4292 case FDESC_EXPR:
4293 /* Go inside any operations that get_inner_reference can handle and see
4294 if what's inside is a constant: no need to do anything here for
4295 addresses of variables or functions. */
4296 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4297 tem = TREE_OPERAND (tem, 0))
4300 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4301 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4302 tem = DECL_INITIAL (tem);
4304 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4305 output_constant_def (tem, 0);
4307 if (TREE_CODE (tem) == MEM_REF)
4308 output_addressed_constants (TREE_OPERAND (tem, 0));
4309 break;
4311 case PLUS_EXPR:
4312 case POINTER_PLUS_EXPR:
4313 case MINUS_EXPR:
4314 output_addressed_constants (TREE_OPERAND (exp, 1));
4315 gcc_fallthrough ();
4317 CASE_CONVERT:
4318 case VIEW_CONVERT_EXPR:
4319 output_addressed_constants (TREE_OPERAND (exp, 0));
4320 break;
4322 case CONSTRUCTOR:
4324 unsigned HOST_WIDE_INT idx;
4325 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4326 if (tem != 0)
4327 output_addressed_constants (tem);
4329 break;
4331 default:
4332 break;
4336 /* Whether a constructor CTOR is a valid static constant initializer if all
4337 its elements are. This used to be internal to initializer_constant_valid_p
4338 and has been exposed to let other functions like categorize_ctor_elements
4339 evaluate the property while walking a constructor for other purposes. */
4341 bool
4342 constructor_static_from_elts_p (const_tree ctor)
4344 return (TREE_CONSTANT (ctor)
4345 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4346 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4347 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4350 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4351 tree *cache);
4353 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4354 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4355 which are valid when ENDTYPE is an integer of any size; in
4356 particular, this does not accept a pointer minus a constant. This
4357 returns null_pointer_node if the VALUE is an absolute constant
4358 which can be used to initialize a static variable. Otherwise it
4359 returns NULL. */
4361 static tree
4362 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4364 tree op0, op1;
4366 if (!INTEGRAL_TYPE_P (endtype))
4367 return NULL_TREE;
4369 op0 = TREE_OPERAND (value, 0);
4370 op1 = TREE_OPERAND (value, 1);
4372 /* Like STRIP_NOPS except allow the operand mode to widen. This
4373 works around a feature of fold that simplifies (int)(p1 - p2) to
4374 ((int)p1 - (int)p2) under the theory that the narrower operation
4375 is cheaper. */
4377 while (CONVERT_EXPR_P (op0)
4378 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4380 tree inner = TREE_OPERAND (op0, 0);
4381 if (inner == error_mark_node
4382 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4383 || (GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (op0)))
4384 > GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (inner)))))
4385 break;
4386 op0 = inner;
4389 while (CONVERT_EXPR_P (op1)
4390 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4392 tree inner = TREE_OPERAND (op1, 0);
4393 if (inner == error_mark_node
4394 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4395 || (GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (op1)))
4396 > GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (inner)))))
4397 break;
4398 op1 = inner;
4401 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4402 if (!op0)
4403 return NULL_TREE;
4405 op1 = initializer_constant_valid_p_1 (op1, endtype,
4406 cache ? cache + 2 : NULL);
4407 /* Both initializers must be known. */
4408 if (op1)
4410 if (op0 == op1
4411 && (op0 == null_pointer_node
4412 || TREE_CODE (value) == MINUS_EXPR))
4413 return null_pointer_node;
4415 /* Support differences between labels. */
4416 if (TREE_CODE (op0) == LABEL_DECL
4417 && TREE_CODE (op1) == LABEL_DECL)
4418 return null_pointer_node;
4420 if (TREE_CODE (op0) == STRING_CST
4421 && TREE_CODE (op1) == STRING_CST
4422 && operand_equal_p (op0, op1, 1))
4423 return null_pointer_node;
4426 return NULL_TREE;
4429 /* Helper function of initializer_constant_valid_p.
4430 Return nonzero if VALUE is a valid constant-valued expression
4431 for use in initializing a static variable; one that can be an
4432 element of a "constant" initializer.
4434 Return null_pointer_node if the value is absolute;
4435 if it is relocatable, return the variable that determines the relocation.
4436 We assume that VALUE has been folded as much as possible;
4437 therefore, we do not need to check for such things as
4438 arithmetic-combinations of integers.
4440 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4442 static tree
4443 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4445 tree ret;
4447 switch (TREE_CODE (value))
4449 case CONSTRUCTOR:
4450 if (constructor_static_from_elts_p (value))
4452 unsigned HOST_WIDE_INT idx;
4453 tree elt;
4454 bool absolute = true;
4456 if (cache && cache[0] == value)
4457 return cache[1];
4458 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4460 tree reloc;
4461 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4462 NULL);
4463 if (!reloc
4464 /* An absolute value is required with reverse SSO. */
4465 || (reloc != null_pointer_node
4466 && TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (value))
4467 && !AGGREGATE_TYPE_P (TREE_TYPE (elt))))
4469 if (cache)
4471 cache[0] = value;
4472 cache[1] = NULL_TREE;
4474 return NULL_TREE;
4476 if (reloc != null_pointer_node)
4477 absolute = false;
4479 /* For a non-absolute relocation, there is no single
4480 variable that can be "the variable that determines the
4481 relocation." */
4482 if (cache)
4484 cache[0] = value;
4485 cache[1] = absolute ? null_pointer_node : error_mark_node;
4487 return absolute ? null_pointer_node : error_mark_node;
4490 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4492 case INTEGER_CST:
4493 case VECTOR_CST:
4494 case REAL_CST:
4495 case FIXED_CST:
4496 case STRING_CST:
4497 case COMPLEX_CST:
4498 return null_pointer_node;
4500 case ADDR_EXPR:
4501 case FDESC_EXPR:
4503 tree op0 = staticp (TREE_OPERAND (value, 0));
4504 if (op0)
4506 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4507 to be a constant, this is old-skool offsetof-like nonsense. */
4508 if (TREE_CODE (op0) == INDIRECT_REF
4509 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4510 return null_pointer_node;
4511 /* Taking the address of a nested function involves a trampoline,
4512 unless we don't need or want one. */
4513 if (TREE_CODE (op0) == FUNCTION_DECL
4514 && DECL_STATIC_CHAIN (op0)
4515 && !TREE_NO_TRAMPOLINE (value))
4516 return NULL_TREE;
4517 /* "&{...}" requires a temporary to hold the constructed
4518 object. */
4519 if (TREE_CODE (op0) == CONSTRUCTOR)
4520 return NULL_TREE;
4522 return op0;
4525 case NON_LVALUE_EXPR:
4526 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4527 endtype, cache);
4529 case VIEW_CONVERT_EXPR:
4531 tree src = TREE_OPERAND (value, 0);
4532 tree src_type = TREE_TYPE (src);
4533 tree dest_type = TREE_TYPE (value);
4535 /* Allow view-conversions from aggregate to non-aggregate type only
4536 if the bit pattern is fully preserved afterwards; otherwise, the
4537 RTL expander won't be able to apply a subsequent transformation
4538 to the underlying constructor. */
4539 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4541 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4542 return initializer_constant_valid_p_1 (src, endtype, cache);
4543 else
4544 return NULL_TREE;
4547 /* Allow all other kinds of view-conversion. */
4548 return initializer_constant_valid_p_1 (src, endtype, cache);
4551 CASE_CONVERT:
4553 tree src = TREE_OPERAND (value, 0);
4554 tree src_type = TREE_TYPE (src);
4555 tree dest_type = TREE_TYPE (value);
4557 /* Allow conversions between pointer types, floating-point
4558 types, and offset types. */
4559 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4560 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4561 || (TREE_CODE (dest_type) == OFFSET_TYPE
4562 && TREE_CODE (src_type) == OFFSET_TYPE))
4563 return initializer_constant_valid_p_1 (src, endtype, cache);
4565 /* Allow length-preserving conversions between integer types. */
4566 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4567 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4568 return initializer_constant_valid_p_1 (src, endtype, cache);
4570 /* Allow conversions between other integer types only if
4571 explicit value. Don't allow sign-extension to a type larger
4572 than word and pointer, there aren't relocations that would
4573 allow to sign extend it to a wider type. */
4574 if (INTEGRAL_TYPE_P (dest_type)
4575 && INTEGRAL_TYPE_P (src_type)
4576 && (TYPE_UNSIGNED (src_type)
4577 || TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type)
4578 || TYPE_PRECISION (dest_type) <= BITS_PER_WORD
4579 || TYPE_PRECISION (dest_type) <= POINTER_SIZE))
4581 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4582 if (inner == null_pointer_node)
4583 return null_pointer_node;
4584 break;
4587 /* Allow (int) &foo provided int is as wide as a pointer. */
4588 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4589 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4590 return initializer_constant_valid_p_1 (src, endtype, cache);
4592 /* Likewise conversions from int to pointers, but also allow
4593 conversions from 0. */
4594 if ((POINTER_TYPE_P (dest_type)
4595 || TREE_CODE (dest_type) == OFFSET_TYPE)
4596 && INTEGRAL_TYPE_P (src_type))
4598 if (TREE_CODE (src) == INTEGER_CST
4599 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4600 return null_pointer_node;
4601 if (integer_zerop (src))
4602 return null_pointer_node;
4603 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4604 return initializer_constant_valid_p_1 (src, endtype, cache);
4607 /* Allow conversions to struct or union types if the value
4608 inside is okay. */
4609 if (TREE_CODE (dest_type) == RECORD_TYPE
4610 || TREE_CODE (dest_type) == UNION_TYPE)
4611 return initializer_constant_valid_p_1 (src, endtype, cache);
4613 break;
4615 case POINTER_PLUS_EXPR:
4616 case PLUS_EXPR:
4617 /* Any valid floating-point constants will have been folded by now;
4618 with -frounding-math we hit this with addition of two constants. */
4619 if (TREE_CODE (endtype) == REAL_TYPE)
4620 return NULL_TREE;
4621 if (cache && cache[0] == value)
4622 return cache[1];
4623 if (! INTEGRAL_TYPE_P (endtype)
4624 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4626 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4627 tree valid0
4628 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4629 endtype, ncache);
4630 tree valid1
4631 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4632 endtype, ncache + 2);
4633 /* If either term is absolute, use the other term's relocation. */
4634 if (valid0 == null_pointer_node)
4635 ret = valid1;
4636 else if (valid1 == null_pointer_node)
4637 ret = valid0;
4638 /* Support narrowing pointer differences. */
4639 else
4640 ret = narrowing_initializer_constant_valid_p (value, endtype,
4641 ncache);
4643 else
4644 /* Support narrowing pointer differences. */
4645 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4646 if (cache)
4648 cache[0] = value;
4649 cache[1] = ret;
4651 return ret;
4653 case POINTER_DIFF_EXPR:
4654 case MINUS_EXPR:
4655 if (TREE_CODE (endtype) == REAL_TYPE)
4656 return NULL_TREE;
4657 if (cache && cache[0] == value)
4658 return cache[1];
4659 if (! INTEGRAL_TYPE_P (endtype)
4660 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4662 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4663 tree valid0
4664 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4665 endtype, ncache);
4666 tree valid1
4667 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4668 endtype, ncache + 2);
4669 /* Win if second argument is absolute. */
4670 if (valid1 == null_pointer_node)
4671 ret = valid0;
4672 /* Win if both arguments have the same relocation.
4673 Then the value is absolute. */
4674 else if (valid0 == valid1 && valid0 != 0)
4675 ret = null_pointer_node;
4676 /* Since GCC guarantees that string constants are unique in the
4677 generated code, a subtraction between two copies of the same
4678 constant string is absolute. */
4679 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4680 && valid1 && TREE_CODE (valid1) == STRING_CST
4681 && operand_equal_p (valid0, valid1, 1))
4682 ret = null_pointer_node;
4683 /* Support narrowing differences. */
4684 else
4685 ret = narrowing_initializer_constant_valid_p (value, endtype,
4686 ncache);
4688 else
4689 /* Support narrowing differences. */
4690 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4691 if (cache)
4693 cache[0] = value;
4694 cache[1] = ret;
4696 return ret;
4698 default:
4699 break;
4702 return NULL_TREE;
4705 /* Return nonzero if VALUE is a valid constant-valued expression
4706 for use in initializing a static variable; one that can be an
4707 element of a "constant" initializer.
4709 Return null_pointer_node if the value is absolute;
4710 if it is relocatable, return the variable that determines the relocation.
4711 We assume that VALUE has been folded as much as possible;
4712 therefore, we do not need to check for such things as
4713 arithmetic-combinations of integers. */
4714 tree
4715 initializer_constant_valid_p (tree value, tree endtype, bool reverse)
4717 tree reloc = initializer_constant_valid_p_1 (value, endtype, NULL);
4719 /* An absolute value is required with reverse storage order. */
4720 if (reloc
4721 && reloc != null_pointer_node
4722 && reverse
4723 && !AGGREGATE_TYPE_P (endtype)
4724 && !VECTOR_TYPE_P (endtype))
4725 reloc = NULL_TREE;
4727 return reloc;
4730 /* Return true if VALUE is a valid constant-valued expression
4731 for use in initializing a static bit-field; one that can be
4732 an element of a "constant" initializer. */
4734 bool
4735 initializer_constant_valid_for_bitfield_p (tree value)
4737 /* For bitfields we support integer constants or possibly nested aggregates
4738 of such. */
4739 switch (TREE_CODE (value))
4741 case CONSTRUCTOR:
4743 unsigned HOST_WIDE_INT idx;
4744 tree elt;
4746 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4747 if (!initializer_constant_valid_for_bitfield_p (elt))
4748 return false;
4749 return true;
4752 case INTEGER_CST:
4753 case REAL_CST:
4754 return true;
4756 case VIEW_CONVERT_EXPR:
4757 case NON_LVALUE_EXPR:
4758 return
4759 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4761 default:
4762 break;
4765 return false;
4768 /* output_constructor outer state of relevance in recursive calls, typically
4769 for nested aggregate bitfields. */
4771 struct oc_outer_state {
4772 unsigned int bit_offset; /* current position in ... */
4773 int byte; /* ... the outer byte buffer. */
4776 static unsigned HOST_WIDE_INT
4777 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int, bool,
4778 oc_outer_state *);
4780 /* Output assembler code for constant EXP, with no label.
4781 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4782 Assumes output_addressed_constants has been done on EXP already.
4784 Generate at least SIZE bytes of assembler data, padding at the end
4785 with zeros if necessary. SIZE must always be specified. The returned
4786 value is the actual number of bytes of assembler data generated, which
4787 may be bigger than SIZE if the object contains a variable length field.
4789 SIZE is important for structure constructors,
4790 since trailing members may have been omitted from the constructor.
4791 It is also important for initialization of arrays from string constants
4792 since the full length of the string constant might not be wanted.
4793 It is also needed for initialization of unions, where the initializer's
4794 type is just one member, and that may not be as long as the union.
4796 There a case in which we would fail to output exactly SIZE bytes:
4797 for a structure constructor that wants to produce more than SIZE bytes.
4798 But such constructors will never be generated for any possible input.
4800 ALIGN is the alignment of the data in bits.
4802 If REVERSE is true, EXP is output in reverse storage order. */
4804 static unsigned HOST_WIDE_INT
4805 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align,
4806 bool reverse)
4808 enum tree_code code;
4809 unsigned HOST_WIDE_INT thissize;
4810 rtx cst;
4812 if (size == 0 || flag_syntax_only)
4813 return size;
4815 /* See if we're trying to initialize a pointer in a non-default mode
4816 to the address of some declaration somewhere. If the target says
4817 the mode is valid for pointers, assume the target has a way of
4818 resolving it. */
4819 if (TREE_CODE (exp) == NOP_EXPR
4820 && POINTER_TYPE_P (TREE_TYPE (exp))
4821 && targetm.addr_space.valid_pointer_mode
4822 (SCALAR_INT_TYPE_MODE (TREE_TYPE (exp)),
4823 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4825 tree saved_type = TREE_TYPE (exp);
4827 /* Peel off any intermediate conversions-to-pointer for valid
4828 pointer modes. */
4829 while (TREE_CODE (exp) == NOP_EXPR
4830 && POINTER_TYPE_P (TREE_TYPE (exp))
4831 && targetm.addr_space.valid_pointer_mode
4832 (SCALAR_INT_TYPE_MODE (TREE_TYPE (exp)),
4833 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4834 exp = TREE_OPERAND (exp, 0);
4836 /* If what we're left with is the address of something, we can
4837 convert the address to the final type and output it that
4838 way. */
4839 if (TREE_CODE (exp) == ADDR_EXPR)
4840 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4841 /* Likewise for constant ints. */
4842 else if (TREE_CODE (exp) == INTEGER_CST)
4843 exp = fold_convert (saved_type, exp);
4847 /* Eliminate any conversions since we'll be outputting the underlying
4848 constant. */
4849 while (CONVERT_EXPR_P (exp)
4850 || TREE_CODE (exp) == NON_LVALUE_EXPR
4851 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4853 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4854 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4856 /* Make sure eliminating the conversion is really a no-op, except with
4857 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4858 union types to allow for Ada unchecked unions. */
4859 if (type_size > op_size
4860 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4861 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4862 /* Keep the conversion. */
4863 break;
4864 else
4865 exp = TREE_OPERAND (exp, 0);
4868 code = TREE_CODE (TREE_TYPE (exp));
4869 thissize = int_size_in_bytes (TREE_TYPE (exp));
4871 /* Allow a constructor with no elements for any data type.
4872 This means to fill the space with zeros. */
4873 if (TREE_CODE (exp) == CONSTRUCTOR
4874 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4876 assemble_zeros (size);
4877 return size;
4880 if (TREE_CODE (exp) == FDESC_EXPR)
4882 #ifdef ASM_OUTPUT_FDESC
4883 HOST_WIDE_INT part = tree_to_shwi (TREE_OPERAND (exp, 1));
4884 tree decl = TREE_OPERAND (exp, 0);
4885 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4886 #else
4887 gcc_unreachable ();
4888 #endif
4889 return size;
4892 /* Now output the underlying data. If we've handling the padding, return.
4893 Otherwise, break and ensure SIZE is the size written. */
4894 switch (code)
4896 case BOOLEAN_TYPE:
4897 case INTEGER_TYPE:
4898 case ENUMERAL_TYPE:
4899 case POINTER_TYPE:
4900 case REFERENCE_TYPE:
4901 case OFFSET_TYPE:
4902 case FIXED_POINT_TYPE:
4903 case POINTER_BOUNDS_TYPE:
4904 case NULLPTR_TYPE:
4905 cst = expand_expr (exp, NULL_RTX, VOIDmode, EXPAND_INITIALIZER);
4906 if (reverse)
4907 cst = flip_storage_order (TYPE_MODE (TREE_TYPE (exp)), cst);
4908 if (!assemble_integer (cst, MIN (size, thissize), align, 0))
4909 error ("initializer for integer/fixed-point value is too complicated");
4910 break;
4912 case REAL_TYPE:
4913 if (TREE_CODE (exp) != REAL_CST)
4914 error ("initializer for floating value is not a floating constant");
4915 else
4916 assemble_real (TREE_REAL_CST (exp),
4917 SCALAR_FLOAT_TYPE_MODE (TREE_TYPE (exp)),
4918 align, reverse);
4919 break;
4921 case COMPLEX_TYPE:
4922 output_constant (TREE_REALPART (exp), thissize / 2, align, reverse);
4923 output_constant (TREE_IMAGPART (exp), thissize / 2,
4924 min_align (align, BITS_PER_UNIT * (thissize / 2)),
4925 reverse);
4926 break;
4928 case ARRAY_TYPE:
4929 case VECTOR_TYPE:
4930 switch (TREE_CODE (exp))
4932 case CONSTRUCTOR:
4933 return output_constructor (exp, size, align, reverse, NULL);
4934 case STRING_CST:
4935 thissize
4936 = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4937 assemble_string (TREE_STRING_POINTER (exp), thissize);
4938 break;
4939 case VECTOR_CST:
4941 scalar_mode inner = SCALAR_TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4942 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4943 int elt_size = GET_MODE_SIZE (inner);
4944 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align,
4945 reverse);
4946 thissize = elt_size;
4947 /* Static constants must have a fixed size. */
4948 unsigned int nunits = VECTOR_CST_NELTS (exp).to_constant ();
4949 for (unsigned int i = 1; i < nunits; i++)
4951 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign,
4952 reverse);
4953 thissize += elt_size;
4955 break;
4957 default:
4958 gcc_unreachable ();
4960 break;
4962 case RECORD_TYPE:
4963 case UNION_TYPE:
4964 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4965 return output_constructor (exp, size, align, reverse, NULL);
4967 case ERROR_MARK:
4968 return 0;
4970 default:
4971 gcc_unreachable ();
4974 if (size > thissize)
4975 assemble_zeros (size - thissize);
4977 return size;
4980 /* Subroutine of output_constructor, used for computing the size of
4981 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4982 type with an unspecified upper bound. */
4984 static unsigned HOST_WIDE_INT
4985 array_size_for_constructor (tree val)
4987 tree max_index;
4988 unsigned HOST_WIDE_INT cnt;
4989 tree index, value, tmp;
4990 offset_int i;
4992 /* This code used to attempt to handle string constants that are not
4993 arrays of single-bytes, but nothing else does, so there's no point in
4994 doing it here. */
4995 if (TREE_CODE (val) == STRING_CST)
4996 return TREE_STRING_LENGTH (val);
4998 max_index = NULL_TREE;
4999 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
5001 if (TREE_CODE (index) == RANGE_EXPR)
5002 index = TREE_OPERAND (index, 1);
5003 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
5004 max_index = index;
5007 if (max_index == NULL_TREE)
5008 return 0;
5010 /* Compute the total number of array elements. */
5011 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
5012 i = wi::to_offset (max_index) - wi::to_offset (tmp) + 1;
5014 /* Multiply by the array element unit size to find number of bytes. */
5015 i *= wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
5017 gcc_assert (wi::fits_uhwi_p (i));
5018 return i.to_uhwi ();
5021 /* Other datastructures + helpers for output_constructor. */
5023 /* output_constructor local state to support interaction with helpers. */
5025 struct oc_local_state {
5027 /* Received arguments. */
5028 tree exp; /* Constructor expression. */
5029 tree type; /* Type of constructor expression. */
5030 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */
5031 unsigned int align; /* Known initial alignment. */
5032 tree min_index; /* Lower bound if specified for an array. */
5034 /* Output processing state. */
5035 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */
5036 int byte; /* Part of a bitfield byte yet to be output. */
5037 int last_relative_index; /* Implicit or explicit index of the last
5038 array element output within a bitfield. */
5039 bool byte_buffer_in_use; /* Whether BYTE is in use. */
5040 bool reverse; /* Whether reverse storage order is in use. */
5042 /* Current element. */
5043 tree field; /* Current field decl in a record. */
5044 tree val; /* Current element value. */
5045 tree index; /* Current element index. */
5049 /* Helper for output_constructor. From the current LOCAL state, output a
5050 RANGE_EXPR element. */
5052 static void
5053 output_constructor_array_range (oc_local_state *local)
5055 unsigned HOST_WIDE_INT fieldsize
5056 = int_size_in_bytes (TREE_TYPE (local->type));
5058 HOST_WIDE_INT lo_index
5059 = tree_to_shwi (TREE_OPERAND (local->index, 0));
5060 HOST_WIDE_INT hi_index
5061 = tree_to_shwi (TREE_OPERAND (local->index, 1));
5062 HOST_WIDE_INT index;
5064 unsigned int align2
5065 = min_align (local->align, fieldsize * BITS_PER_UNIT);
5067 for (index = lo_index; index <= hi_index; index++)
5069 /* Output the element's initial value. */
5070 if (local->val == NULL_TREE)
5071 assemble_zeros (fieldsize);
5072 else
5073 fieldsize
5074 = output_constant (local->val, fieldsize, align2, local->reverse);
5076 /* Count its size. */
5077 local->total_bytes += fieldsize;
5081 /* Helper for output_constructor. From the current LOCAL state, output a
5082 field element that is not true bitfield or part of an outer one. */
5084 static void
5085 output_constructor_regular_field (oc_local_state *local)
5087 /* Field size and position. Since this structure is static, we know the
5088 positions are constant. */
5089 unsigned HOST_WIDE_INT fieldsize;
5090 HOST_WIDE_INT fieldpos;
5092 unsigned int align2;
5094 /* Output any buffered-up bit-fields preceding this element. */
5095 if (local->byte_buffer_in_use)
5097 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5098 local->total_bytes++;
5099 local->byte_buffer_in_use = false;
5102 if (local->index != NULL_TREE)
5104 /* Perform the index calculation in modulo arithmetic but
5105 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
5106 but we are using an unsigned sizetype. */
5107 unsigned prec = TYPE_PRECISION (sizetype);
5108 offset_int idx = wi::sext (wi::to_offset (local->index)
5109 - wi::to_offset (local->min_index), prec);
5110 fieldpos = (idx * wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (local->val))))
5111 .to_short_addr ();
5113 else if (local->field != NULL_TREE)
5114 fieldpos = int_byte_position (local->field);
5115 else
5116 fieldpos = 0;
5118 /* Advance to offset of this element.
5119 Note no alignment needed in an array, since that is guaranteed
5120 if each element has the proper size. */
5121 if (local->field != NULL_TREE || local->index != NULL_TREE)
5123 if (fieldpos > local->total_bytes)
5125 assemble_zeros (fieldpos - local->total_bytes);
5126 local->total_bytes = fieldpos;
5128 else
5129 /* Must not go backwards. */
5130 gcc_assert (fieldpos == local->total_bytes);
5133 /* Find the alignment of this element. */
5134 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
5136 /* Determine size this element should occupy. */
5137 if (local->field)
5139 fieldsize = 0;
5141 /* If this is an array with an unspecified upper bound,
5142 the initializer determines the size. */
5143 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
5144 but we cannot do this until the deprecated support for
5145 initializing zero-length array members is removed. */
5146 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
5147 && (!TYPE_DOMAIN (TREE_TYPE (local->field))
5148 || !TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field)))))
5150 fieldsize = array_size_for_constructor (local->val);
5151 /* Given a non-empty initialization, this field had better
5152 be last. Given a flexible array member, the next field
5153 on the chain is a TYPE_DECL of the enclosing struct. */
5154 const_tree next = DECL_CHAIN (local->field);
5155 gcc_assert (!fieldsize || !next || TREE_CODE (next) != FIELD_DECL);
5157 else
5158 fieldsize = tree_to_uhwi (DECL_SIZE_UNIT (local->field));
5160 else
5161 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
5163 /* Output the element's initial value. */
5164 if (local->val == NULL_TREE)
5165 assemble_zeros (fieldsize);
5166 else
5167 fieldsize
5168 = output_constant (local->val, fieldsize, align2, local->reverse);
5170 /* Count its size. */
5171 local->total_bytes += fieldsize;
5174 /* Helper for output_constructor. From the LOCAL state, output an element
5175 that is a true bitfield or part of an outer one. BIT_OFFSET is the offset
5176 from the start of a possibly ongoing outer byte buffer. */
5178 static void
5179 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
5181 /* Bit size of this element. */
5182 HOST_WIDE_INT ebitsize
5183 = (local->field
5184 ? tree_to_uhwi (DECL_SIZE (local->field))
5185 : tree_to_uhwi (TYPE_SIZE (TREE_TYPE (local->type))));
5187 /* Relative index of this element if this is an array component. */
5188 HOST_WIDE_INT relative_index
5189 = (!local->field
5190 ? (local->index
5191 ? (tree_to_shwi (local->index)
5192 - tree_to_shwi (local->min_index))
5193 : local->last_relative_index + 1)
5194 : 0);
5196 /* Bit position of this element from the start of the containing
5197 constructor. */
5198 HOST_WIDE_INT constructor_relative_ebitpos
5199 = (local->field
5200 ? int_bit_position (local->field)
5201 : ebitsize * relative_index);
5203 /* Bit position of this element from the start of a possibly ongoing
5204 outer byte buffer. */
5205 HOST_WIDE_INT byte_relative_ebitpos
5206 = bit_offset + constructor_relative_ebitpos;
5208 /* From the start of a possibly ongoing outer byte buffer, offsets to
5209 the first bit of this element and to the first bit past the end of
5210 this element. */
5211 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
5212 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
5214 local->last_relative_index = relative_index;
5216 if (local->val == NULL_TREE)
5217 local->val = integer_zero_node;
5219 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
5220 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
5221 local->val = TREE_OPERAND (local->val, 0);
5223 if (TREE_CODE (local->val) != INTEGER_CST
5224 && TREE_CODE (local->val) != CONSTRUCTOR)
5226 error ("invalid initial value for member %qE", DECL_NAME (local->field));
5227 return;
5230 /* If this field does not start in this (or next) byte, skip some bytes. */
5231 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5233 /* Output remnant of any bit field in previous bytes. */
5234 if (local->byte_buffer_in_use)
5236 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5237 local->total_bytes++;
5238 local->byte_buffer_in_use = false;
5241 /* If still not at proper byte, advance to there. */
5242 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5244 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
5245 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
5246 local->total_bytes = next_offset / BITS_PER_UNIT;
5250 /* Set up the buffer if necessary. */
5251 if (!local->byte_buffer_in_use)
5253 local->byte = 0;
5254 if (ebitsize > 0)
5255 local->byte_buffer_in_use = true;
5258 /* If this is nested constructor, recurse passing the bit offset and the
5259 pending data, then retrieve the new pending data afterwards. */
5260 if (TREE_CODE (local->val) == CONSTRUCTOR)
5262 oc_outer_state temp_state;
5263 temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5264 temp_state.byte = local->byte;
5265 local->total_bytes
5266 += output_constructor (local->val, 0, 0, local->reverse, &temp_state);
5267 local->byte = temp_state.byte;
5268 return;
5271 /* Otherwise, we must split the element into pieces that fall within
5272 separate bytes, and combine each byte with previous or following
5273 bit-fields. */
5274 while (next_offset < end_offset)
5276 int this_time;
5277 int shift;
5278 HOST_WIDE_INT value;
5279 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5280 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5282 /* Advance from byte to byte within this element when necessary. */
5283 while (next_byte != local->total_bytes)
5285 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5286 local->total_bytes++;
5287 local->byte = 0;
5290 /* Number of bits we can process at once (all part of the same byte). */
5291 this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5292 if (local->reverse ? !BYTES_BIG_ENDIAN : BYTES_BIG_ENDIAN)
5294 /* For big-endian data, take the most significant bits (of the
5295 bits that are significant) first and put them into bytes from
5296 the most significant end. */
5297 shift = end_offset - next_offset - this_time;
5299 /* Don't try to take a bunch of bits that cross
5300 the word boundary in the INTEGER_CST. We can
5301 only select bits from one element. */
5302 if ((shift / HOST_BITS_PER_WIDE_INT)
5303 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5305 const int end = shift + this_time - 1;
5306 shift = end & -HOST_BITS_PER_WIDE_INT;
5307 this_time = end - shift + 1;
5310 /* Now get the bits from the appropriate constant word. */
5311 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5312 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5314 /* Get the result. This works only when:
5315 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5316 local->byte |= (((value >> shift)
5317 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5318 << (BITS_PER_UNIT - this_time - next_bit));
5320 else
5322 /* On little-endian machines, take the least significant bits of
5323 the value first and pack them starting at the least significant
5324 bits of the bytes. */
5325 shift = next_offset - byte_relative_ebitpos;
5327 /* Don't try to take a bunch of bits that cross
5328 the word boundary in the INTEGER_CST. We can
5329 only select bits from one element. */
5330 if ((shift / HOST_BITS_PER_WIDE_INT)
5331 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5332 this_time
5333 = HOST_BITS_PER_WIDE_INT - (shift & (HOST_BITS_PER_WIDE_INT - 1));
5335 /* Now get the bits from the appropriate constant word. */
5336 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5337 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5339 /* Get the result. This works only when:
5340 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5341 local->byte |= (((value >> shift)
5342 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5343 << next_bit);
5346 next_offset += this_time;
5347 local->byte_buffer_in_use = true;
5351 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5352 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5353 caller output state of relevance in recursive invocations. */
5355 static unsigned HOST_WIDE_INT
5356 output_constructor (tree exp, unsigned HOST_WIDE_INT size, unsigned int align,
5357 bool reverse, oc_outer_state *outer)
5359 unsigned HOST_WIDE_INT cnt;
5360 constructor_elt *ce;
5361 oc_local_state local;
5363 /* Setup our local state to communicate with helpers. */
5364 local.exp = exp;
5365 local.type = TREE_TYPE (exp);
5366 local.size = size;
5367 local.align = align;
5368 if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5369 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5370 else
5371 local.min_index = integer_zero_node;
5373 local.total_bytes = 0;
5374 local.byte_buffer_in_use = outer != NULL;
5375 local.byte = outer ? outer->byte : 0;
5376 local.last_relative_index = -1;
5377 /* The storage order is specified for every aggregate type. */
5378 if (AGGREGATE_TYPE_P (local.type))
5379 local.reverse = TYPE_REVERSE_STORAGE_ORDER (local.type);
5380 else
5381 local.reverse = reverse;
5383 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5385 /* As CE goes through the elements of the constant, FIELD goes through the
5386 structure fields if the constant is a structure. If the constant is a
5387 union, we override this by getting the field from the TREE_LIST element.
5388 But the constant could also be an array. Then FIELD is zero.
5390 There is always a maximum of one element in the chain LINK for unions
5391 (even if the initializer in a source program incorrectly contains
5392 more one). */
5394 if (TREE_CODE (local.type) == RECORD_TYPE)
5395 local.field = TYPE_FIELDS (local.type);
5396 else
5397 local.field = NULL_TREE;
5399 for (cnt = 0;
5400 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5401 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5403 local.val = ce->value;
5404 local.index = NULL_TREE;
5406 /* The element in a union constructor specifies the proper field
5407 or index. */
5408 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5409 local.field = ce->index;
5411 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5412 local.index = ce->index;
5414 if (local.field && flag_verbose_asm)
5415 fprintf (asm_out_file, "%s %s:\n",
5416 ASM_COMMENT_START,
5417 DECL_NAME (local.field)
5418 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5419 : "<anonymous>");
5421 /* Eliminate the marker that makes a cast not be an lvalue. */
5422 if (local.val != NULL_TREE)
5423 STRIP_NOPS (local.val);
5425 /* Output the current element, using the appropriate helper ... */
5427 /* For an array slice not part of an outer bitfield. */
5428 if (!outer
5429 && local.index != NULL_TREE
5430 && TREE_CODE (local.index) == RANGE_EXPR)
5431 output_constructor_array_range (&local);
5433 /* For a field that is neither a true bitfield nor part of an outer one,
5434 known to be at least byte aligned and multiple-of-bytes long. */
5435 else if (!outer
5436 && (local.field == NULL_TREE
5437 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5438 output_constructor_regular_field (&local);
5440 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5441 supported for scalar fields, so we may need to convert first. */
5442 else
5444 if (TREE_CODE (local.val) == REAL_CST)
5445 local.val
5446 = fold_unary (VIEW_CONVERT_EXPR,
5447 build_nonstandard_integer_type
5448 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5449 local.val);
5450 output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5454 /* If we are not at toplevel, save the pending data for our caller.
5455 Otherwise output the pending data and padding zeros as needed. */
5456 if (outer)
5457 outer->byte = local.byte;
5458 else
5460 if (local.byte_buffer_in_use)
5462 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5463 local.total_bytes++;
5466 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5468 assemble_zeros (local.size - local.total_bytes);
5469 local.total_bytes = local.size;
5473 return local.total_bytes;
5476 /* Mark DECL as weak. */
5478 static void
5479 mark_weak (tree decl)
5481 if (DECL_WEAK (decl))
5482 return;
5484 struct symtab_node *n = symtab_node::get (decl);
5485 if (n && n->refuse_visibility_changes)
5486 error ("%+qD declared weak after being used", decl);
5487 DECL_WEAK (decl) = 1;
5489 if (DECL_RTL_SET_P (decl)
5490 && MEM_P (DECL_RTL (decl))
5491 && XEXP (DECL_RTL (decl), 0)
5492 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5493 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5496 /* Merge weak status between NEWDECL and OLDDECL. */
5498 void
5499 merge_weak (tree newdecl, tree olddecl)
5501 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5503 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5505 tree *pwd;
5506 /* We put the NEWDECL on the weak_decls list at some point
5507 and OLDDECL as well. Keep just OLDDECL on the list. */
5508 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5509 if (TREE_VALUE (*pwd) == newdecl)
5511 *pwd = TREE_CHAIN (*pwd);
5512 break;
5515 return;
5518 if (DECL_WEAK (newdecl))
5520 tree wd;
5522 /* NEWDECL is weak, but OLDDECL is not. */
5524 /* If we already output the OLDDECL, we're in trouble; we can't
5525 go back and make it weak. This should never happen in
5526 unit-at-a-time compilation. */
5527 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5529 /* If we've already generated rtl referencing OLDDECL, we may
5530 have done so in a way that will not function properly with
5531 a weak symbol. Again in unit-at-a-time this should be
5532 impossible. */
5533 gcc_assert (!TREE_USED (olddecl)
5534 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5536 /* PR 49899: You cannot convert a static function into a weak, public function. */
5537 if (! TREE_PUBLIC (olddecl) && TREE_PUBLIC (newdecl))
5538 error ("weak declaration of %q+D being applied to a already "
5539 "existing, static definition", newdecl);
5541 if (TARGET_SUPPORTS_WEAK)
5543 /* We put the NEWDECL on the weak_decls list at some point.
5544 Replace it with the OLDDECL. */
5545 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5546 if (TREE_VALUE (wd) == newdecl)
5548 TREE_VALUE (wd) = olddecl;
5549 break;
5551 /* We may not find the entry on the list. If NEWDECL is a
5552 weak alias, then we will have already called
5553 globalize_decl to remove the entry; in that case, we do
5554 not need to do anything. */
5557 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5558 mark_weak (olddecl);
5560 else
5561 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5562 weak. Just update NEWDECL to indicate that it's weak too. */
5563 mark_weak (newdecl);
5566 /* Declare DECL to be a weak symbol. */
5568 void
5569 declare_weak (tree decl)
5571 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5572 if (! TREE_PUBLIC (decl))
5574 error ("weak declaration of %q+D must be public", decl);
5575 return;
5577 else if (!TARGET_SUPPORTS_WEAK)
5578 warning (0, "weak declaration of %q+D not supported", decl);
5580 mark_weak (decl);
5581 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5582 DECL_ATTRIBUTES (decl)
5583 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5586 static void
5587 weak_finish_1 (tree decl)
5589 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5590 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5591 #endif
5593 if (! TREE_USED (decl))
5594 return;
5596 #ifdef ASM_WEAKEN_DECL
5597 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5598 #else
5599 #ifdef ASM_WEAKEN_LABEL
5600 ASM_WEAKEN_LABEL (asm_out_file, name);
5601 #else
5602 #ifdef ASM_OUTPUT_WEAK_ALIAS
5604 static bool warn_once = 0;
5605 if (! warn_once)
5607 warning (0, "only weak aliases are supported in this configuration");
5608 warn_once = 1;
5610 return;
5612 #endif
5613 #endif
5614 #endif
5617 /* Fiven an assembly name, find the decl it is associated with. */
5618 static tree
5619 find_decl (tree target)
5621 symtab_node *node = symtab_node::get_for_asmname (target);
5622 if (node)
5623 return node->decl;
5624 return NULL_TREE;
5627 /* This TREE_LIST contains weakref targets. */
5629 static GTY(()) tree weakref_targets;
5631 /* Emit any pending weak declarations. */
5633 void
5634 weak_finish (void)
5636 tree t;
5638 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5640 tree alias_decl = TREE_PURPOSE (t);
5641 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5643 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5644 /* Remove alias_decl from the weak list, but leave entries for
5645 the target alone. */
5646 target = NULL_TREE;
5647 #ifndef ASM_OUTPUT_WEAKREF
5648 else if (! TREE_SYMBOL_REFERENCED (target))
5650 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5651 defined, otherwise we and weak_finish_1 would use
5652 different macros. */
5653 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5654 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5655 # else
5656 tree decl = find_decl (target);
5658 if (! decl)
5660 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5661 TREE_CODE (alias_decl), target,
5662 TREE_TYPE (alias_decl));
5664 DECL_EXTERNAL (decl) = 1;
5665 TREE_PUBLIC (decl) = 1;
5666 DECL_ARTIFICIAL (decl) = 1;
5667 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5668 TREE_USED (decl) = 1;
5671 weak_finish_1 (decl);
5672 # endif
5674 #endif
5677 tree *p;
5678 tree t2;
5680 /* Remove the alias and the target from the pending weak list
5681 so that we do not emit any .weak directives for the former,
5682 nor multiple .weak directives for the latter. */
5683 for (p = &weak_decls; (t2 = *p) ; )
5685 if (TREE_VALUE (t2) == alias_decl
5686 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5687 *p = TREE_CHAIN (t2);
5688 else
5689 p = &TREE_CHAIN (t2);
5692 /* Remove other weakrefs to the same target, to speed things up. */
5693 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5695 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5696 *p = TREE_CHAIN (t2);
5697 else
5698 p = &TREE_CHAIN (t2);
5703 for (t = weak_decls; t; t = TREE_CHAIN (t))
5705 tree decl = TREE_VALUE (t);
5707 weak_finish_1 (decl);
5711 /* Emit the assembly bits to indicate that DECL is globally visible. */
5713 static void
5714 globalize_decl (tree decl)
5717 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5718 if (DECL_WEAK (decl))
5720 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5721 tree *p, t;
5723 #ifdef ASM_WEAKEN_DECL
5724 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5725 #else
5726 ASM_WEAKEN_LABEL (asm_out_file, name);
5727 #endif
5729 /* Remove this function from the pending weak list so that
5730 we do not emit multiple .weak directives for it. */
5731 for (p = &weak_decls; (t = *p) ; )
5733 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5734 *p = TREE_CHAIN (t);
5735 else
5736 p = &TREE_CHAIN (t);
5739 /* Remove weakrefs to the same target from the pending weakref
5740 list, for the same reason. */
5741 for (p = &weakref_targets; (t = *p) ; )
5743 if (DECL_ASSEMBLER_NAME (decl)
5744 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5745 *p = TREE_CHAIN (t);
5746 else
5747 p = &TREE_CHAIN (t);
5750 return;
5752 #endif
5754 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5757 vec<alias_pair, va_gc> *alias_pairs;
5759 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5760 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5761 tree node is DECL to have the value of the tree node TARGET. */
5763 void
5764 do_assemble_alias (tree decl, tree target)
5766 tree id;
5768 /* Emulated TLS had better not get this var. */
5769 gcc_assert (!(!targetm.have_tls
5770 && VAR_P (decl)
5771 && DECL_THREAD_LOCAL_P (decl)));
5773 if (TREE_ASM_WRITTEN (decl))
5774 return;
5776 id = DECL_ASSEMBLER_NAME (decl);
5777 ultimate_transparent_alias_target (&id);
5778 ultimate_transparent_alias_target (&target);
5780 /* We must force creation of DECL_RTL for debug info generation, even though
5781 we don't use it here. */
5782 make_decl_rtl (decl);
5784 TREE_ASM_WRITTEN (decl) = 1;
5785 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5786 TREE_ASM_WRITTEN (id) = 1;
5788 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5790 if (!TREE_SYMBOL_REFERENCED (target))
5791 weakref_targets = tree_cons (decl, target, weakref_targets);
5793 #ifdef ASM_OUTPUT_WEAKREF
5794 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5795 IDENTIFIER_POINTER (id),
5796 IDENTIFIER_POINTER (target));
5797 #else
5798 if (!TARGET_SUPPORTS_WEAK)
5800 error_at (DECL_SOURCE_LOCATION (decl),
5801 "weakref is not supported in this configuration");
5802 return;
5804 #endif
5805 return;
5808 #ifdef ASM_OUTPUT_DEF
5809 tree orig_decl = decl;
5811 if (TREE_CODE (decl) == FUNCTION_DECL
5812 && cgraph_node::get (decl)->instrumentation_clone
5813 && cgraph_node::get (decl)->instrumented_version)
5814 orig_decl = cgraph_node::get (decl)->instrumented_version->decl;
5816 /* Make name accessible from other files, if appropriate. */
5818 if (TREE_PUBLIC (decl) || TREE_PUBLIC (orig_decl))
5820 globalize_decl (decl);
5821 maybe_assemble_visibility (decl);
5823 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5825 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5826 if (targetm.has_ifunc_p ())
5827 ASM_OUTPUT_TYPE_DIRECTIVE
5828 (asm_out_file, IDENTIFIER_POINTER (id),
5829 IFUNC_ASM_TYPE);
5830 else
5831 #endif
5832 error_at (DECL_SOURCE_LOCATION (decl),
5833 "ifunc is not supported on this target");
5836 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5837 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5838 # else
5839 ASM_OUTPUT_DEF (asm_out_file,
5840 IDENTIFIER_POINTER (id),
5841 IDENTIFIER_POINTER (target));
5842 # endif
5843 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5845 const char *name;
5846 tree *p, t;
5848 name = IDENTIFIER_POINTER (id);
5849 # ifdef ASM_WEAKEN_DECL
5850 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5851 # else
5852 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5853 # endif
5854 /* Remove this function from the pending weak list so that
5855 we do not emit multiple .weak directives for it. */
5856 for (p = &weak_decls; (t = *p) ; )
5857 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t))
5858 || id == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5859 *p = TREE_CHAIN (t);
5860 else
5861 p = &TREE_CHAIN (t);
5863 /* Remove weakrefs to the same target from the pending weakref
5864 list, for the same reason. */
5865 for (p = &weakref_targets; (t = *p) ; )
5867 if (id == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5868 *p = TREE_CHAIN (t);
5869 else
5870 p = &TREE_CHAIN (t);
5873 #endif
5876 /* Emit an assembler directive to make the symbol for DECL an alias to
5877 the symbol for TARGET. */
5879 void
5880 assemble_alias (tree decl, tree target)
5882 tree target_decl;
5884 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5886 tree alias = DECL_ASSEMBLER_NAME (decl);
5888 ultimate_transparent_alias_target (&target);
5890 if (alias == target)
5891 error ("weakref %q+D ultimately targets itself", decl);
5892 if (TREE_PUBLIC (decl))
5893 error ("weakref %q+D must have static linkage", decl);
5895 else
5897 #if !defined (ASM_OUTPUT_DEF)
5898 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5899 error_at (DECL_SOURCE_LOCATION (decl),
5900 "alias definitions not supported in this configuration");
5901 TREE_ASM_WRITTEN (decl) = 1;
5902 return;
5903 # else
5904 if (!DECL_WEAK (decl))
5906 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5907 error_at (DECL_SOURCE_LOCATION (decl),
5908 "ifunc is not supported in this configuration");
5909 else
5910 error_at (DECL_SOURCE_LOCATION (decl),
5911 "only weak aliases are supported in this configuration");
5912 TREE_ASM_WRITTEN (decl) = 1;
5913 return;
5915 # endif
5916 #endif
5918 TREE_USED (decl) = 1;
5920 /* Allow aliases to aliases. */
5921 if (TREE_CODE (decl) == FUNCTION_DECL)
5922 cgraph_node::get_create (decl)->alias = true;
5923 else
5924 varpool_node::get_create (decl)->alias = true;
5926 /* If the target has already been emitted, we don't have to queue the
5927 alias. This saves a tad of memory. */
5928 if (symtab->global_info_ready)
5929 target_decl = find_decl (target);
5930 else
5931 target_decl= NULL;
5932 if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5933 || symtab->state >= EXPANSION)
5934 do_assemble_alias (decl, target);
5935 else
5937 alias_pair p = {decl, target};
5938 vec_safe_push (alias_pairs, p);
5942 /* Record and output a table of translations from original function
5943 to its transaction aware clone. Note that tm_pure functions are
5944 considered to be their own clone. */
5946 struct tm_clone_hasher : ggc_cache_ptr_hash<tree_map>
5948 static hashval_t hash (tree_map *m) { return tree_map_hash (m); }
5949 static bool equal (tree_map *a, tree_map *b) { return tree_map_eq (a, b); }
5951 static int
5952 keep_cache_entry (tree_map *&e)
5954 return ggc_marked_p (e->base.from);
5958 static GTY((cache)) hash_table<tm_clone_hasher> *tm_clone_hash;
5960 void
5961 record_tm_clone_pair (tree o, tree n)
5963 struct tree_map **slot, *h;
5965 if (tm_clone_hash == NULL)
5966 tm_clone_hash = hash_table<tm_clone_hasher>::create_ggc (32);
5968 h = ggc_alloc<tree_map> ();
5969 h->hash = htab_hash_pointer (o);
5970 h->base.from = o;
5971 h->to = n;
5973 slot = tm_clone_hash->find_slot_with_hash (h, h->hash, INSERT);
5974 *slot = h;
5977 tree
5978 get_tm_clone_pair (tree o)
5980 if (tm_clone_hash)
5982 struct tree_map *h, in;
5984 in.base.from = o;
5985 in.hash = htab_hash_pointer (o);
5986 h = tm_clone_hash->find_with_hash (&in, in.hash);
5987 if (h)
5988 return h->to;
5990 return NULL_TREE;
5993 struct tm_alias_pair
5995 unsigned int uid;
5996 tree from;
5997 tree to;
6001 /* Dump the actual pairs to the .tm_clone_table section. */
6003 static void
6004 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
6006 unsigned i;
6007 tm_alias_pair *p;
6008 bool switched = false;
6010 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
6012 tree src = p->from;
6013 tree dst = p->to;
6014 struct cgraph_node *src_n = cgraph_node::get (src);
6015 struct cgraph_node *dst_n = cgraph_node::get (dst);
6017 /* The function ipa_tm_create_version() marks the clone as needed if
6018 the original function was needed. But we also mark the clone as
6019 needed if we ever called the clone indirectly through
6020 TM_GETTMCLONE. If neither of these are true, we didn't generate
6021 a clone, and we didn't call it indirectly... no sense keeping it
6022 in the clone table. */
6023 if (!dst_n || !dst_n->definition)
6024 continue;
6026 /* This covers the case where we have optimized the original
6027 function away, and only access the transactional clone. */
6028 if (!src_n || !src_n->definition)
6029 continue;
6031 if (!switched)
6033 switch_to_section (targetm.asm_out.tm_clone_table_section ());
6034 assemble_align (POINTER_SIZE);
6035 switched = true;
6038 assemble_integer (XEXP (DECL_RTL (src), 0),
6039 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
6040 assemble_integer (XEXP (DECL_RTL (dst), 0),
6041 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
6045 /* Provide a default for the tm_clone_table section. */
6047 section *
6048 default_clone_table_section (void)
6050 return get_named_section (NULL, ".tm_clone_table", 3);
6053 /* Helper comparison function for qsorting by the DECL_UID stored in
6054 alias_pair->emitted_diags. */
6056 static int
6057 tm_alias_pair_cmp (const void *x, const void *y)
6059 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
6060 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
6061 if (p1->uid < p2->uid)
6062 return -1;
6063 if (p1->uid > p2->uid)
6064 return 1;
6065 return 0;
6068 void
6069 finish_tm_clone_pairs (void)
6071 vec<tm_alias_pair> tm_alias_pairs = vNULL;
6073 if (tm_clone_hash == NULL)
6074 return;
6076 /* We need a determenistic order for the .tm_clone_table, otherwise
6077 we will get bootstrap comparison failures, so dump the hash table
6078 to a vector, sort it, and dump the vector. */
6080 /* Dump the hashtable to a vector. */
6081 tree_map *map;
6082 hash_table<tm_clone_hasher>::iterator iter;
6083 FOR_EACH_HASH_TABLE_ELEMENT (*tm_clone_hash, map, tree_map *, iter)
6085 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
6086 tm_alias_pairs.safe_push (p);
6088 /* Sort it. */
6089 tm_alias_pairs.qsort (tm_alias_pair_cmp);
6091 /* Dump it. */
6092 dump_tm_clone_pairs (tm_alias_pairs);
6094 tm_clone_hash->empty ();
6095 tm_clone_hash = NULL;
6096 tm_alias_pairs.release ();
6100 /* Emit an assembler directive to set symbol for DECL visibility to
6101 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
6103 void
6104 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
6105 int vis ATTRIBUTE_UNUSED)
6107 #ifdef HAVE_GAS_HIDDEN
6108 static const char * const visibility_types[] = {
6109 NULL, "protected", "hidden", "internal"
6112 const char *name, *type;
6113 tree id;
6115 id = DECL_ASSEMBLER_NAME (decl);
6116 ultimate_transparent_alias_target (&id);
6117 name = IDENTIFIER_POINTER (id);
6119 type = visibility_types[vis];
6121 fprintf (asm_out_file, "\t.%s\t", type);
6122 assemble_name (asm_out_file, name);
6123 fprintf (asm_out_file, "\n");
6124 #else
6125 if (!DECL_ARTIFICIAL (decl))
6126 warning (OPT_Wattributes, "visibility attribute not supported "
6127 "in this configuration; ignored");
6128 #endif
6131 /* A helper function to call assemble_visibility when needed for a decl. */
6134 maybe_assemble_visibility (tree decl)
6136 enum symbol_visibility vis = DECL_VISIBILITY (decl);
6138 if (TREE_CODE (decl) == FUNCTION_DECL
6139 && cgraph_node::get (decl)
6140 && cgraph_node::get (decl)->instrumentation_clone
6141 && cgraph_node::get (decl)->instrumented_version)
6142 vis = DECL_VISIBILITY (cgraph_node::get (decl)->instrumented_version->decl);
6144 if (vis != VISIBILITY_DEFAULT)
6146 targetm.asm_out.assemble_visibility (decl, vis);
6147 return 1;
6149 else
6150 return 0;
6153 /* Returns 1 if the target configuration supports defining public symbols
6154 so that one of them will be chosen at link time instead of generating a
6155 multiply-defined symbol error, whether through the use of weak symbols or
6156 a target-specific mechanism for having duplicates discarded. */
6159 supports_one_only (void)
6161 if (SUPPORTS_ONE_ONLY)
6162 return 1;
6163 return TARGET_SUPPORTS_WEAK;
6166 /* Set up DECL as a public symbol that can be defined in multiple
6167 translation units without generating a linker error. */
6169 void
6170 make_decl_one_only (tree decl, tree comdat_group)
6172 struct symtab_node *symbol;
6173 gcc_assert (VAR_OR_FUNCTION_DECL_P (decl));
6175 TREE_PUBLIC (decl) = 1;
6177 if (VAR_P (decl))
6178 symbol = varpool_node::get_create (decl);
6179 else
6180 symbol = cgraph_node::get_create (decl);
6182 if (SUPPORTS_ONE_ONLY)
6184 #ifdef MAKE_DECL_ONE_ONLY
6185 MAKE_DECL_ONE_ONLY (decl);
6186 #endif
6187 symbol->set_comdat_group (comdat_group);
6189 else if (VAR_P (decl)
6190 && (DECL_INITIAL (decl) == 0
6191 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
6192 DECL_COMMON (decl) = 1;
6193 else
6195 gcc_assert (TARGET_SUPPORTS_WEAK);
6196 DECL_WEAK (decl) = 1;
6200 void
6201 init_varasm_once (void)
6203 section_htab = hash_table<section_hasher>::create_ggc (31);
6204 object_block_htab = hash_table<object_block_hasher>::create_ggc (31);
6205 const_desc_htab = hash_table<tree_descriptor_hasher>::create_ggc (1009);
6207 shared_constant_pool = create_constant_pool ();
6209 #ifdef TEXT_SECTION_ASM_OP
6210 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
6211 TEXT_SECTION_ASM_OP);
6212 #endif
6214 #ifdef DATA_SECTION_ASM_OP
6215 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
6216 DATA_SECTION_ASM_OP);
6217 #endif
6219 #ifdef SDATA_SECTION_ASM_OP
6220 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
6221 SDATA_SECTION_ASM_OP);
6222 #endif
6224 #ifdef READONLY_DATA_SECTION_ASM_OP
6225 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
6226 READONLY_DATA_SECTION_ASM_OP);
6227 #endif
6229 #ifdef CTORS_SECTION_ASM_OP
6230 ctors_section = get_unnamed_section (0, output_section_asm_op,
6231 CTORS_SECTION_ASM_OP);
6232 #endif
6234 #ifdef DTORS_SECTION_ASM_OP
6235 dtors_section = get_unnamed_section (0, output_section_asm_op,
6236 DTORS_SECTION_ASM_OP);
6237 #endif
6239 #ifdef BSS_SECTION_ASM_OP
6240 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6241 output_section_asm_op,
6242 BSS_SECTION_ASM_OP);
6243 #endif
6245 #ifdef SBSS_SECTION_ASM_OP
6246 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6247 output_section_asm_op,
6248 SBSS_SECTION_ASM_OP);
6249 #endif
6251 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6252 | SECTION_COMMON, emit_tls_common);
6253 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6254 | SECTION_COMMON, emit_local);
6255 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6256 | SECTION_COMMON, emit_common);
6258 #if defined ASM_OUTPUT_ALIGNED_BSS
6259 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
6260 emit_bss);
6261 #endif
6263 targetm.asm_out.init_sections ();
6265 if (readonly_data_section == NULL)
6266 readonly_data_section = text_section;
6268 #ifdef ASM_OUTPUT_EXTERNAL
6269 pending_assemble_externals_set = new hash_set<tree>;
6270 #endif
6273 enum tls_model
6274 decl_default_tls_model (const_tree decl)
6276 enum tls_model kind;
6277 bool is_local;
6279 is_local = targetm.binds_local_p (decl);
6280 if (!flag_shlib)
6282 if (is_local)
6283 kind = TLS_MODEL_LOCAL_EXEC;
6284 else
6285 kind = TLS_MODEL_INITIAL_EXEC;
6288 /* Local dynamic is inefficient when we're not combining the
6289 parts of the address. */
6290 else if (optimize && is_local)
6291 kind = TLS_MODEL_LOCAL_DYNAMIC;
6292 else
6293 kind = TLS_MODEL_GLOBAL_DYNAMIC;
6294 if (kind < flag_tls_default)
6295 kind = flag_tls_default;
6297 return kind;
6300 /* Select a set of attributes for section NAME based on the properties
6301 of DECL and whether or not RELOC indicates that DECL's initializer
6302 might contain runtime relocations.
6304 We make the section read-only and executable for a function decl,
6305 read-only for a const data decl, and writable for a non-const data decl. */
6307 unsigned int
6308 default_section_type_flags (tree decl, const char *name, int reloc)
6310 unsigned int flags;
6312 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6313 flags = SECTION_CODE;
6314 else if (decl)
6316 enum section_category category
6317 = categorize_decl_for_section (decl, reloc);
6318 if (decl_readonly_section_1 (category))
6319 flags = 0;
6320 else if (category == SECCAT_DATA_REL_RO
6321 || category == SECCAT_DATA_REL_RO_LOCAL)
6322 flags = SECTION_WRITE | SECTION_RELRO;
6323 else
6324 flags = SECTION_WRITE;
6326 else
6328 flags = SECTION_WRITE;
6329 if (strcmp (name, ".data.rel.ro") == 0
6330 || strcmp (name, ".data.rel.ro.local") == 0)
6331 flags |= SECTION_RELRO;
6334 if (decl && DECL_P (decl) && DECL_COMDAT_GROUP (decl))
6335 flags |= SECTION_LINKONCE;
6337 if (strcmp (name, ".vtable_map_vars") == 0)
6338 flags |= SECTION_LINKONCE;
6340 if (decl && VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6341 flags |= SECTION_TLS | SECTION_WRITE;
6343 if (strcmp (name, ".bss") == 0
6344 || strncmp (name, ".bss.", 5) == 0
6345 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6346 || strcmp (name, ".persistent.bss") == 0
6347 || strcmp (name, ".sbss") == 0
6348 || strncmp (name, ".sbss.", 6) == 0
6349 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6350 flags |= SECTION_BSS;
6352 if (strcmp (name, ".tdata") == 0
6353 || strncmp (name, ".tdata.", 7) == 0
6354 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6355 flags |= SECTION_TLS;
6357 if (strcmp (name, ".tbss") == 0
6358 || strncmp (name, ".tbss.", 6) == 0
6359 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6360 flags |= SECTION_TLS | SECTION_BSS;
6362 /* These three sections have special ELF types. They are neither
6363 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
6364 want to print a section type (@progbits or @nobits). If someone
6365 is silly enough to emit code or TLS variables to one of these
6366 sections, then don't handle them specially. */
6367 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6368 && (strcmp (name, ".init_array") == 0
6369 || strcmp (name, ".fini_array") == 0
6370 || strcmp (name, ".preinit_array") == 0))
6371 flags |= SECTION_NOTYPE;
6373 return flags;
6376 /* Return true if the target supports some form of global BSS,
6377 either through bss_noswitch_section, or by selecting a BSS
6378 section in TARGET_ASM_SELECT_SECTION. */
6380 bool
6381 have_global_bss_p (void)
6383 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6386 /* Output assembly to switch to section NAME with attribute FLAGS.
6387 Four variants for common object file formats. */
6389 void
6390 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6391 unsigned int flags ATTRIBUTE_UNUSED,
6392 tree decl ATTRIBUTE_UNUSED)
6394 /* Some object formats don't support named sections at all. The
6395 front-end should already have flagged this as an error. */
6396 gcc_unreachable ();
6399 #ifndef TLS_SECTION_ASM_FLAG
6400 #define TLS_SECTION_ASM_FLAG 'T'
6401 #endif
6403 void
6404 default_elf_asm_named_section (const char *name, unsigned int flags,
6405 tree decl)
6407 char flagchars[11], *f = flagchars;
6408 unsigned int numeric_value = 0;
6410 /* If we have already declared this section, we can use an
6411 abbreviated form to switch back to it -- unless this section is
6412 part of a COMDAT groups, in which case GAS requires the full
6413 declaration every time. */
6414 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6415 && (flags & SECTION_DECLARED))
6417 fprintf (asm_out_file, "\t.section\t%s\n", name);
6418 return;
6421 /* If we have a machine specific flag, then use the numeric value to pass
6422 this on to GAS. */
6423 if (targetm.asm_out.elf_flags_numeric (flags, &numeric_value))
6424 snprintf (f, sizeof (flagchars), "0x%08x", numeric_value);
6425 else
6427 if (!(flags & SECTION_DEBUG))
6428 *f++ = 'a';
6429 #if defined (HAVE_GAS_SECTION_EXCLUDE) && HAVE_GAS_SECTION_EXCLUDE == 1
6430 if (flags & SECTION_EXCLUDE)
6431 *f++ = 'e';
6432 #endif
6433 if (flags & SECTION_WRITE)
6434 *f++ = 'w';
6435 if (flags & SECTION_CODE)
6436 *f++ = 'x';
6437 if (flags & SECTION_SMALL)
6438 *f++ = 's';
6439 if (flags & SECTION_MERGE)
6440 *f++ = 'M';
6441 if (flags & SECTION_STRINGS)
6442 *f++ = 'S';
6443 if (flags & SECTION_TLS)
6444 *f++ = TLS_SECTION_ASM_FLAG;
6445 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6446 *f++ = 'G';
6447 #ifdef MACH_DEP_SECTION_ASM_FLAG
6448 if (flags & SECTION_MACH_DEP)
6449 *f++ = MACH_DEP_SECTION_ASM_FLAG;
6450 #endif
6451 *f = '\0';
6454 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6456 if (!(flags & SECTION_NOTYPE))
6458 const char *type;
6459 const char *format;
6461 if (flags & SECTION_BSS)
6462 type = "nobits";
6463 else
6464 type = "progbits";
6466 format = ",@%s";
6467 /* On platforms that use "@" as the assembly comment character,
6468 use "%" instead. */
6469 if (strcmp (ASM_COMMENT_START, "@") == 0)
6470 format = ",%%%s";
6471 fprintf (asm_out_file, format, type);
6473 if (flags & SECTION_ENTSIZE)
6474 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6475 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6477 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6478 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6479 else
6480 fprintf (asm_out_file, ",%s,comdat",
6481 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6485 putc ('\n', asm_out_file);
6488 void
6489 default_coff_asm_named_section (const char *name, unsigned int flags,
6490 tree decl ATTRIBUTE_UNUSED)
6492 char flagchars[8], *f = flagchars;
6494 if (flags & SECTION_WRITE)
6495 *f++ = 'w';
6496 if (flags & SECTION_CODE)
6497 *f++ = 'x';
6498 *f = '\0';
6500 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6503 void
6504 default_pe_asm_named_section (const char *name, unsigned int flags,
6505 tree decl)
6507 default_coff_asm_named_section (name, flags, decl);
6509 if (flags & SECTION_LINKONCE)
6511 /* Functions may have been compiled at various levels of
6512 optimization so we can't use `same_size' here.
6513 Instead, have the linker pick one. */
6514 fprintf (asm_out_file, "\t.linkonce %s\n",
6515 (flags & SECTION_CODE ? "discard" : "same_size"));
6519 /* The lame default section selector. */
6521 section *
6522 default_select_section (tree decl, int reloc,
6523 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6525 if (DECL_P (decl))
6527 if (decl_readonly_section (decl, reloc))
6528 return readonly_data_section;
6530 else if (TREE_CODE (decl) == CONSTRUCTOR)
6532 if (! ((flag_pic && reloc)
6533 || !TREE_READONLY (decl)
6534 || TREE_SIDE_EFFECTS (decl)
6535 || !TREE_CONSTANT (decl)))
6536 return readonly_data_section;
6538 else if (TREE_CODE (decl) == STRING_CST)
6539 return readonly_data_section;
6540 else if (! (flag_pic && reloc))
6541 return readonly_data_section;
6543 return data_section;
6546 enum section_category
6547 categorize_decl_for_section (const_tree decl, int reloc)
6549 enum section_category ret;
6551 if (TREE_CODE (decl) == FUNCTION_DECL)
6552 return SECCAT_TEXT;
6553 else if (TREE_CODE (decl) == STRING_CST)
6555 if ((flag_sanitize & SANITIZE_ADDRESS)
6556 && asan_protect_global (CONST_CAST_TREE (decl)))
6557 /* or !flag_merge_constants */
6558 return SECCAT_RODATA;
6559 else
6560 return SECCAT_RODATA_MERGE_STR;
6562 else if (VAR_P (decl))
6564 tree d = CONST_CAST_TREE (decl);
6565 if (bss_initializer_p (decl))
6566 ret = SECCAT_BSS;
6567 else if (! TREE_READONLY (decl)
6568 || TREE_SIDE_EFFECTS (decl)
6569 || (DECL_INITIAL (decl)
6570 && ! TREE_CONSTANT (DECL_INITIAL (decl))))
6572 /* Here the reloc_rw_mask is not testing whether the section should
6573 be read-only or not, but whether the dynamic link will have to
6574 do something. If so, we wish to segregate the data in order to
6575 minimize cache misses inside the dynamic linker. */
6576 if (reloc & targetm.asm_out.reloc_rw_mask ())
6577 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6578 else
6579 ret = SECCAT_DATA;
6581 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6582 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6583 else if (reloc || flag_merge_constants < 2
6584 || ((flag_sanitize & SANITIZE_ADDRESS)
6585 /* PR 81697: for architectures that use section anchors we
6586 need to ignore DECL_RTL_SET_P (decl) for string constants
6587 inside this asan_protect_global call because otherwise
6588 we'll wrongly put them into SECCAT_RODATA_MERGE_CONST
6589 section, set DECL_RTL (decl) later on and add DECL to
6590 protected globals via successive asan_protect_global
6591 calls. In this scenario we'll end up with wrong
6592 alignment of these strings at runtime and possible ASan
6593 false positives. */
6594 && asan_protect_global (d, use_object_blocks_p ()
6595 && use_blocks_for_decl_p (d))))
6596 /* C and C++ don't allow different variables to share the same
6597 location. -fmerge-all-constants allows even that (at the
6598 expense of not conforming). */
6599 ret = SECCAT_RODATA;
6600 else if (DECL_INITIAL (decl)
6601 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6602 ret = SECCAT_RODATA_MERGE_STR_INIT;
6603 else
6604 ret = SECCAT_RODATA_MERGE_CONST;
6606 else if (TREE_CODE (decl) == CONSTRUCTOR)
6608 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6609 || TREE_SIDE_EFFECTS (decl)
6610 || ! TREE_CONSTANT (decl))
6611 ret = SECCAT_DATA;
6612 else
6613 ret = SECCAT_RODATA;
6615 else
6616 ret = SECCAT_RODATA;
6618 /* There are no read-only thread-local sections. */
6619 if (VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6621 /* Note that this would be *just* SECCAT_BSS, except that there's
6622 no concept of a read-only thread-local-data section. */
6623 if (ret == SECCAT_BSS
6624 || DECL_INITIAL (decl) == NULL
6625 || (flag_zero_initialized_in_bss
6626 && initializer_zerop (DECL_INITIAL (decl))))
6627 ret = SECCAT_TBSS;
6628 else
6629 ret = SECCAT_TDATA;
6632 /* If the target uses small data sections, select it. */
6633 else if (targetm.in_small_data_p (decl))
6635 if (ret == SECCAT_BSS)
6636 ret = SECCAT_SBSS;
6637 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6638 ret = SECCAT_SRODATA;
6639 else
6640 ret = SECCAT_SDATA;
6643 return ret;
6646 static bool
6647 decl_readonly_section_1 (enum section_category category)
6649 switch (category)
6651 case SECCAT_RODATA:
6652 case SECCAT_RODATA_MERGE_STR:
6653 case SECCAT_RODATA_MERGE_STR_INIT:
6654 case SECCAT_RODATA_MERGE_CONST:
6655 case SECCAT_SRODATA:
6656 return true;
6657 default:
6658 return false;
6662 bool
6663 decl_readonly_section (const_tree decl, int reloc)
6665 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6668 /* Select a section based on the above categorization. */
6670 section *
6671 default_elf_select_section (tree decl, int reloc,
6672 unsigned HOST_WIDE_INT align)
6674 const char *sname;
6675 switch (categorize_decl_for_section (decl, reloc))
6677 case SECCAT_TEXT:
6678 /* We're not supposed to be called on FUNCTION_DECLs. */
6679 gcc_unreachable ();
6680 case SECCAT_RODATA:
6681 return readonly_data_section;
6682 case SECCAT_RODATA_MERGE_STR:
6683 return mergeable_string_section (decl, align, 0);
6684 case SECCAT_RODATA_MERGE_STR_INIT:
6685 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6686 case SECCAT_RODATA_MERGE_CONST:
6687 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6688 case SECCAT_SRODATA:
6689 sname = ".sdata2";
6690 break;
6691 case SECCAT_DATA:
6692 return data_section;
6693 case SECCAT_DATA_REL:
6694 sname = ".data.rel";
6695 break;
6696 case SECCAT_DATA_REL_LOCAL:
6697 sname = ".data.rel.local";
6698 break;
6699 case SECCAT_DATA_REL_RO:
6700 sname = ".data.rel.ro";
6701 break;
6702 case SECCAT_DATA_REL_RO_LOCAL:
6703 sname = ".data.rel.ro.local";
6704 break;
6705 case SECCAT_SDATA:
6706 sname = ".sdata";
6707 break;
6708 case SECCAT_TDATA:
6709 sname = ".tdata";
6710 break;
6711 case SECCAT_BSS:
6712 if (bss_section)
6713 return bss_section;
6714 sname = ".bss";
6715 break;
6716 case SECCAT_SBSS:
6717 sname = ".sbss";
6718 break;
6719 case SECCAT_TBSS:
6720 sname = ".tbss";
6721 break;
6722 default:
6723 gcc_unreachable ();
6726 return get_named_section (decl, sname, reloc);
6729 /* Construct a unique section name based on the decl name and the
6730 categorization performed above. */
6732 void
6733 default_unique_section (tree decl, int reloc)
6735 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6736 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6737 const char *prefix, *name, *linkonce;
6738 char *string;
6739 tree id;
6741 switch (categorize_decl_for_section (decl, reloc))
6743 case SECCAT_TEXT:
6744 prefix = one_only ? ".t" : ".text";
6745 break;
6746 case SECCAT_RODATA:
6747 case SECCAT_RODATA_MERGE_STR:
6748 case SECCAT_RODATA_MERGE_STR_INIT:
6749 case SECCAT_RODATA_MERGE_CONST:
6750 prefix = one_only ? ".r" : ".rodata";
6751 break;
6752 case SECCAT_SRODATA:
6753 prefix = one_only ? ".s2" : ".sdata2";
6754 break;
6755 case SECCAT_DATA:
6756 prefix = one_only ? ".d" : ".data";
6757 break;
6758 case SECCAT_DATA_REL:
6759 prefix = one_only ? ".d.rel" : ".data.rel";
6760 break;
6761 case SECCAT_DATA_REL_LOCAL:
6762 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6763 break;
6764 case SECCAT_DATA_REL_RO:
6765 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6766 break;
6767 case SECCAT_DATA_REL_RO_LOCAL:
6768 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6769 break;
6770 case SECCAT_SDATA:
6771 prefix = one_only ? ".s" : ".sdata";
6772 break;
6773 case SECCAT_BSS:
6774 prefix = one_only ? ".b" : ".bss";
6775 break;
6776 case SECCAT_SBSS:
6777 prefix = one_only ? ".sb" : ".sbss";
6778 break;
6779 case SECCAT_TDATA:
6780 prefix = one_only ? ".td" : ".tdata";
6781 break;
6782 case SECCAT_TBSS:
6783 prefix = one_only ? ".tb" : ".tbss";
6784 break;
6785 default:
6786 gcc_unreachable ();
6789 id = DECL_ASSEMBLER_NAME (decl);
6790 ultimate_transparent_alias_target (&id);
6791 name = IDENTIFIER_POINTER (id);
6792 name = targetm.strip_name_encoding (name);
6794 /* If we're using one_only, then there needs to be a .gnu.linkonce
6795 prefix to the section name. */
6796 linkonce = one_only ? ".gnu.linkonce" : "";
6798 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6800 set_decl_section_name (decl, string);
6803 /* Subroutine of compute_reloc_for_rtx for leaf rtxes. */
6805 static int
6806 compute_reloc_for_rtx_1 (const_rtx x)
6808 switch (GET_CODE (x))
6810 case SYMBOL_REF:
6811 return SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6812 case LABEL_REF:
6813 return 1;
6814 default:
6815 return 0;
6819 /* Like compute_reloc_for_constant, except for an RTX. The return value
6820 is a mask for which bit 1 indicates a global relocation, and bit 0
6821 indicates a local relocation. */
6823 static int
6824 compute_reloc_for_rtx (const_rtx x)
6826 switch (GET_CODE (x))
6828 case SYMBOL_REF:
6829 case LABEL_REF:
6830 return compute_reloc_for_rtx_1 (x);
6832 case CONST:
6834 int reloc = 0;
6835 subrtx_iterator::array_type array;
6836 FOR_EACH_SUBRTX (iter, array, x, ALL)
6837 reloc |= compute_reloc_for_rtx_1 (*iter);
6838 return reloc;
6841 default:
6842 return 0;
6846 section *
6847 default_select_rtx_section (machine_mode mode ATTRIBUTE_UNUSED,
6848 rtx x,
6849 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6851 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6852 return data_section;
6853 else
6854 return readonly_data_section;
6857 section *
6858 default_elf_select_rtx_section (machine_mode mode, rtx x,
6859 unsigned HOST_WIDE_INT align)
6861 int reloc = compute_reloc_for_rtx (x);
6863 /* ??? Handle small data here somehow. */
6865 if (reloc & targetm.asm_out.reloc_rw_mask ())
6867 if (reloc == 1)
6868 return get_named_section (NULL, ".data.rel.ro.local", 1);
6869 else
6870 return get_named_section (NULL, ".data.rel.ro", 3);
6873 return mergeable_constant_section (mode, align, 0);
6876 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6878 void
6879 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6881 rtx symbol;
6882 int flags;
6884 /* Careful not to prod global register variables. */
6885 if (!MEM_P (rtl))
6886 return;
6887 symbol = XEXP (rtl, 0);
6888 if (GET_CODE (symbol) != SYMBOL_REF)
6889 return;
6891 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6892 if (TREE_CODE (decl) == FUNCTION_DECL)
6893 flags |= SYMBOL_FLAG_FUNCTION;
6894 if (targetm.binds_local_p (decl))
6895 flags |= SYMBOL_FLAG_LOCAL;
6896 if (VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6897 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6898 else if (targetm.in_small_data_p (decl))
6899 flags |= SYMBOL_FLAG_SMALL;
6900 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6901 being PUBLIC, the thing *must* be defined in this translation unit.
6902 Prevent this buglet from being propagated into rtl code as well. */
6903 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6904 flags |= SYMBOL_FLAG_EXTERNAL;
6906 SYMBOL_REF_FLAGS (symbol) = flags;
6909 /* By default, we do nothing for encode_section_info, so we need not
6910 do anything but discard the '*' marker. */
6912 const char *
6913 default_strip_name_encoding (const char *str)
6915 return str + (*str == '*');
6918 #ifdef ASM_OUTPUT_DEF
6919 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6920 anchor relative to ".", the current section position. */
6922 void
6923 default_asm_output_anchor (rtx symbol)
6925 char buffer[100];
6927 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6928 SYMBOL_REF_BLOCK_OFFSET (symbol));
6929 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6931 #endif
6933 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6935 bool
6936 default_use_anchors_for_symbol_p (const_rtx symbol)
6938 section *sect;
6939 tree decl;
6941 /* Don't use anchors for mergeable sections. The linker might move
6942 the objects around. */
6943 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6944 if (sect->common.flags & SECTION_MERGE)
6945 return false;
6947 /* Don't use anchors for small data sections. The small data register
6948 acts as an anchor for such sections. */
6949 if (sect->common.flags & SECTION_SMALL)
6950 return false;
6952 decl = SYMBOL_REF_DECL (symbol);
6953 if (decl && DECL_P (decl))
6955 /* Don't use section anchors for decls that might be defined or
6956 usurped by other modules. */
6957 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6958 return false;
6960 /* Don't use section anchors for decls that will be placed in a
6961 small data section. */
6962 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6963 one above. The problem is that we only use SECTION_SMALL for
6964 sections that should be marked as small in the section directive. */
6965 if (targetm.in_small_data_p (decl))
6966 return false;
6968 /* Don't use section anchors for decls that won't fit inside a single
6969 anchor range to reduce the amount of instructions required to refer
6970 to the entire declaration. */
6971 if (DECL_SIZE_UNIT (decl) == NULL_TREE
6972 || !tree_fits_uhwi_p (DECL_SIZE_UNIT (decl))
6973 || (tree_to_uhwi (DECL_SIZE_UNIT (decl))
6974 >= (unsigned HOST_WIDE_INT) targetm.max_anchor_offset))
6975 return false;
6978 return true;
6981 /* Return true when RESOLUTION indicate that symbol will be bound to the
6982 definition provided by current .o file. */
6984 static bool
6985 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
6987 return (resolution == LDPR_PREVAILING_DEF
6988 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6989 || resolution == LDPR_PREVAILING_DEF_IRONLY);
6992 /* Return true when RESOLUTION indicate that symbol will be bound locally
6993 within current executable or DSO. */
6995 static bool
6996 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
6998 return (resolution == LDPR_PREVAILING_DEF
6999 || resolution == LDPR_PREVAILING_DEF_IRONLY
7000 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
7001 || resolution == LDPR_PREEMPTED_REG
7002 || resolution == LDPR_PREEMPTED_IR
7003 || resolution == LDPR_RESOLVED_IR
7004 || resolution == LDPR_RESOLVED_EXEC);
7007 /* COMMON_LOCAL_P is true means that the linker can guarantee that an
7008 uninitialized common symbol in the executable will still be defined
7009 (through COPY relocation) in the executable. */
7011 bool
7012 default_binds_local_p_3 (const_tree exp, bool shlib, bool weak_dominate,
7013 bool extern_protected_data, bool common_local_p)
7015 /* A non-decl is an entry in the constant pool. */
7016 if (!DECL_P (exp))
7017 return true;
7019 /* Weakrefs may not bind locally, even though the weakref itself is always
7020 static and therefore local. Similarly, the resolver for ifunc functions
7021 might resolve to a non-local function.
7022 FIXME: We can resolve the weakref case more curefuly by looking at the
7023 weakref alias. */
7024 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
7025 || (TREE_CODE (exp) == FUNCTION_DECL
7026 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
7027 return false;
7029 /* Static variables are always local. */
7030 if (! TREE_PUBLIC (exp))
7031 return true;
7033 /* With resolution file in hand, take look into resolutions.
7034 We can't just return true for resolved_locally symbols,
7035 because dynamic linking might overwrite symbols
7036 in shared libraries. */
7037 bool resolved_locally = false;
7039 bool uninited_common = (DECL_COMMON (exp)
7040 && (DECL_INITIAL (exp) == NULL
7041 || (!in_lto_p
7042 && DECL_INITIAL (exp) == error_mark_node)));
7044 /* A non-external variable is defined locally only if it isn't
7045 uninitialized COMMON variable or common_local_p is true. */
7046 bool defined_locally = (!DECL_EXTERNAL (exp)
7047 && (!uninited_common || common_local_p));
7048 if (symtab_node *node = symtab_node::get (exp))
7050 if (node->in_other_partition)
7051 defined_locally = true;
7052 if (node->can_be_discarded_p ())
7054 else if (resolution_to_local_definition_p (node->resolution))
7055 defined_locally = resolved_locally = true;
7056 else if (resolution_local_p (node->resolution))
7057 resolved_locally = true;
7059 if (defined_locally && weak_dominate && !shlib)
7060 resolved_locally = true;
7062 /* Undefined weak symbols are never defined locally. */
7063 if (DECL_WEAK (exp) && !defined_locally)
7064 return false;
7066 /* A symbol is local if the user has said explicitly that it will be,
7067 or if we have a definition for the symbol. We cannot infer visibility
7068 for undefined symbols. */
7069 if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT
7070 && (TREE_CODE (exp) == FUNCTION_DECL
7071 || !extern_protected_data
7072 || DECL_VISIBILITY (exp) != VISIBILITY_PROTECTED)
7073 && (DECL_VISIBILITY_SPECIFIED (exp) || defined_locally))
7074 return true;
7076 /* If PIC, then assume that any global name can be overridden by
7077 symbols resolved from other modules. */
7078 if (shlib)
7079 return false;
7081 /* Variables defined outside this object might not be local. */
7082 if (DECL_EXTERNAL (exp) && !resolved_locally)
7083 return false;
7085 /* Non-dominant weak symbols are not defined locally. */
7086 if (DECL_WEAK (exp) && !resolved_locally)
7087 return false;
7089 /* Uninitialized COMMON variable may be unified with symbols
7090 resolved from other modules. */
7091 if (uninited_common && !resolved_locally)
7092 return false;
7094 /* Otherwise we're left with initialized (or non-common) global data
7095 which is of necessity defined locally. */
7096 return true;
7099 /* Assume ELF-ish defaults, since that's pretty much the most liberal
7100 wrt cross-module name binding. */
7102 bool
7103 default_binds_local_p (const_tree exp)
7105 return default_binds_local_p_3 (exp, flag_shlib != 0, true, false, false);
7108 /* Similar to default_binds_local_p, but common symbol may be local and
7109 extern protected data is non-local. */
7111 bool
7112 default_binds_local_p_2 (const_tree exp)
7114 return default_binds_local_p_3 (exp, flag_shlib != 0, true, true,
7115 !flag_pic);
7118 bool
7119 default_binds_local_p_1 (const_tree exp, int shlib)
7121 return default_binds_local_p_3 (exp, shlib != 0, false, false, false);
7124 /* Return true when references to DECL must bind to current definition in
7125 final executable.
7127 The condition is usually equivalent to whether the function binds to the
7128 current module (shared library or executable), that is to binds_local_p.
7129 We use this fact to avoid need for another target hook and implement
7130 the logic using binds_local_p and just special cases where
7131 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
7132 the weak definitions (that can be overwritten at linktime by other
7133 definition from different object file) and when resolution info is available
7134 we simply use the knowledge passed to us by linker plugin. */
7135 bool
7136 decl_binds_to_current_def_p (const_tree decl)
7138 gcc_assert (DECL_P (decl));
7139 if (!targetm.binds_local_p (decl))
7140 return false;
7141 if (!TREE_PUBLIC (decl))
7142 return true;
7144 /* When resolution is available, just use it. */
7145 if (symtab_node *node = symtab_node::get (decl))
7147 if (node->resolution != LDPR_UNKNOWN
7148 && !node->can_be_discarded_p ())
7149 return resolution_to_local_definition_p (node->resolution);
7152 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
7153 binds locally but still can be overwritten), DECL_COMMON (can be merged
7154 with a non-common definition somewhere in the same module) or
7155 DECL_EXTERNAL.
7156 This rely on fact that binds_local_p behave as decl_replaceable_p
7157 for all other declaration types. */
7158 if (DECL_WEAK (decl))
7159 return false;
7160 if (DECL_COMMON (decl)
7161 && (DECL_INITIAL (decl) == NULL
7162 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
7163 return false;
7164 if (DECL_EXTERNAL (decl))
7165 return false;
7166 return true;
7169 /* A replaceable function or variable is one which may be replaced
7170 at link-time with an entirely different definition, provided that the
7171 replacement has the same type. For example, functions declared
7172 with __attribute__((weak)) on most systems are replaceable.
7174 COMDAT functions are not replaceable, since all definitions of the
7175 function must be equivalent. It is important that COMDAT functions
7176 not be treated as replaceable so that use of C++ template
7177 instantiations is not penalized. */
7179 bool
7180 decl_replaceable_p (tree decl)
7182 gcc_assert (DECL_P (decl));
7183 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
7184 return false;
7185 if (!flag_semantic_interposition
7186 && !DECL_WEAK (decl))
7187 return false;
7188 return !decl_binds_to_current_def_p (decl);
7191 /* Default function to output code that will globalize a label. A
7192 target must define GLOBAL_ASM_OP or provide its own function to
7193 globalize a label. */
7194 #ifdef GLOBAL_ASM_OP
7195 void
7196 default_globalize_label (FILE * stream, const char *name)
7198 fputs (GLOBAL_ASM_OP, stream);
7199 assemble_name (stream, name);
7200 putc ('\n', stream);
7202 #endif /* GLOBAL_ASM_OP */
7204 /* Default function to output code that will globalize a declaration. */
7205 void
7206 default_globalize_decl_name (FILE * stream, tree decl)
7208 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
7209 targetm.asm_out.globalize_label (stream, name);
7212 /* Default function to output a label for unwind information. The
7213 default is to do nothing. A target that needs nonlocal labels for
7214 unwind information must provide its own function to do this. */
7215 void
7216 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
7217 tree decl ATTRIBUTE_UNUSED,
7218 int for_eh ATTRIBUTE_UNUSED,
7219 int empty ATTRIBUTE_UNUSED)
7223 /* Default function to output a label to divide up the exception table.
7224 The default is to do nothing. A target that needs/wants to divide
7225 up the table must provide it's own function to do this. */
7226 void
7227 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
7231 /* This is how to output an internal numbered label where PREFIX is
7232 the class of label and LABELNO is the number within the class. */
7234 void
7235 default_generate_internal_label (char *buf, const char *prefix,
7236 unsigned long labelno)
7238 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
7241 /* This is how to output an internal numbered label where PREFIX is
7242 the class of label and LABELNO is the number within the class. */
7244 void
7245 default_internal_label (FILE *stream, const char *prefix,
7246 unsigned long labelno)
7248 char *const buf = (char *) alloca (40 + strlen (prefix));
7249 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
7250 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
7254 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
7256 void
7257 default_asm_declare_constant_name (FILE *file, const char *name,
7258 const_tree exp ATTRIBUTE_UNUSED,
7259 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
7261 assemble_label (file, name);
7264 /* This is the default behavior at the beginning of a file. It's
7265 controlled by two other target-hook toggles. */
7266 void
7267 default_file_start (void)
7269 if (targetm.asm_file_start_app_off
7270 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
7271 fputs (ASM_APP_OFF, asm_out_file);
7273 if (targetm.asm_file_start_file_directive)
7275 /* LTO produced units have no meaningful main_input_filename. */
7276 if (in_lto_p)
7277 output_file_directive (asm_out_file, "<artificial>");
7278 else
7279 output_file_directive (asm_out_file, main_input_filename);
7283 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
7284 which emits a special section directive used to indicate whether or
7285 not this object file needs an executable stack. This is primarily
7286 a GNU extension to ELF but could be used on other targets. */
7288 int trampolines_created;
7290 void
7291 file_end_indicate_exec_stack (void)
7293 unsigned int flags = SECTION_DEBUG;
7294 if (trampolines_created)
7295 flags |= SECTION_CODE;
7297 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
7300 /* Emit a special section directive to indicate that this object file
7301 was compiled with -fsplit-stack. This is used to let the linker
7302 detect calls between split-stack code and non-split-stack code, so
7303 that it can modify the split-stack code to allocate a sufficiently
7304 large stack. We emit another special section if there are any
7305 functions in this file which have the no_split_stack attribute, to
7306 prevent the linker from warning about being unable to convert the
7307 functions if they call non-split-stack code. */
7309 void
7310 file_end_indicate_split_stack (void)
7312 if (flag_split_stack)
7314 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
7315 NULL));
7316 if (saw_no_split_stack)
7317 switch_to_section (get_section (".note.GNU-no-split-stack",
7318 SECTION_DEBUG, NULL));
7322 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
7323 a get_unnamed_section callback. */
7325 void
7326 output_section_asm_op (const void *directive)
7328 fprintf (asm_out_file, "%s\n", (const char *) directive);
7331 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
7332 the current section is NEW_SECTION. */
7334 void
7335 switch_to_section (section *new_section)
7337 if (in_section == new_section)
7338 return;
7340 if (new_section->common.flags & SECTION_FORGET)
7341 in_section = NULL;
7342 else
7343 in_section = new_section;
7345 switch (SECTION_STYLE (new_section))
7347 case SECTION_NAMED:
7348 targetm.asm_out.named_section (new_section->named.name,
7349 new_section->named.common.flags,
7350 new_section->named.decl);
7351 break;
7353 case SECTION_UNNAMED:
7354 new_section->unnamed.callback (new_section->unnamed.data);
7355 break;
7357 case SECTION_NOSWITCH:
7358 gcc_unreachable ();
7359 break;
7362 new_section->common.flags |= SECTION_DECLARED;
7365 /* If block symbol SYMBOL has not yet been assigned an offset, place
7366 it at the end of its block. */
7368 void
7369 place_block_symbol (rtx symbol)
7371 unsigned HOST_WIDE_INT size, mask, offset;
7372 struct constant_descriptor_rtx *desc;
7373 unsigned int alignment;
7374 struct object_block *block;
7375 tree decl;
7377 gcc_assert (SYMBOL_REF_BLOCK (symbol));
7378 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7379 return;
7381 /* Work out the symbol's size and alignment. */
7382 if (CONSTANT_POOL_ADDRESS_P (symbol))
7384 desc = SYMBOL_REF_CONSTANT (symbol);
7385 alignment = desc->align;
7386 size = GET_MODE_SIZE (desc->mode);
7388 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7390 decl = SYMBOL_REF_DECL (symbol);
7391 gcc_checking_assert (DECL_IN_CONSTANT_POOL (decl));
7392 alignment = DECL_ALIGN (decl);
7393 size = get_constant_size (DECL_INITIAL (decl));
7394 if ((flag_sanitize & SANITIZE_ADDRESS)
7395 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7396 && asan_protect_global (DECL_INITIAL (decl)))
7398 size += asan_red_zone_size (size);
7399 alignment = MAX (alignment,
7400 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7403 else
7405 struct symtab_node *snode;
7406 decl = SYMBOL_REF_DECL (symbol);
7408 snode = symtab_node::get (decl);
7409 if (snode->alias)
7411 rtx target = DECL_RTL (snode->ultimate_alias_target ()->decl);
7413 gcc_assert (MEM_P (target)
7414 && GET_CODE (XEXP (target, 0)) == SYMBOL_REF
7415 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (target, 0)));
7416 target = XEXP (target, 0);
7417 place_block_symbol (target);
7418 SYMBOL_REF_BLOCK_OFFSET (symbol) = SYMBOL_REF_BLOCK_OFFSET (target);
7419 return;
7421 alignment = get_variable_align (decl);
7422 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7423 if ((flag_sanitize & SANITIZE_ADDRESS)
7424 && asan_protect_global (decl))
7426 size += asan_red_zone_size (size);
7427 alignment = MAX (alignment,
7428 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7432 /* Calculate the object's offset from the start of the block. */
7433 block = SYMBOL_REF_BLOCK (symbol);
7434 mask = alignment / BITS_PER_UNIT - 1;
7435 offset = (block->size + mask) & ~mask;
7436 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7438 /* Record the block's new alignment and size. */
7439 block->alignment = MAX (block->alignment, alignment);
7440 block->size = offset + size;
7442 vec_safe_push (block->objects, symbol);
7445 /* Return the anchor that should be used to address byte offset OFFSET
7446 from the first object in BLOCK. MODEL is the TLS model used
7447 to access it. */
7450 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7451 enum tls_model model)
7453 char label[100];
7454 unsigned int begin, middle, end;
7455 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7456 rtx anchor;
7458 /* Work out the anchor's offset. Use an offset of 0 for the first
7459 anchor so that we don't pessimize the case where we take the address
7460 of a variable at the beginning of the block. This is particularly
7461 useful when a block has only one variable assigned to it.
7463 We try to place anchors RANGE bytes apart, so there can then be
7464 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7465 a ptr_mode offset. With some target settings, the lowest such
7466 anchor might be out of range for the lowest ptr_mode offset;
7467 likewise the highest anchor for the highest offset. Use anchors
7468 at the extreme ends of the ptr_mode range in such cases.
7470 All arithmetic uses unsigned integers in order to avoid
7471 signed overflow. */
7472 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7473 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7474 range = max_offset - min_offset + 1;
7475 if (range == 0)
7476 offset = 0;
7477 else
7479 bias = HOST_WIDE_INT_1U << (GET_MODE_BITSIZE (ptr_mode) - 1);
7480 if (offset < 0)
7482 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7483 delta -= delta % range;
7484 if (delta > bias)
7485 delta = bias;
7486 offset = (HOST_WIDE_INT) (-delta);
7488 else
7490 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7491 delta -= delta % range;
7492 if (delta > bias - 1)
7493 delta = bias - 1;
7494 offset = (HOST_WIDE_INT) delta;
7498 /* Do a binary search to see if there's already an anchor we can use.
7499 Set BEGIN to the new anchor's index if not. */
7500 begin = 0;
7501 end = vec_safe_length (block->anchors);
7502 while (begin != end)
7504 middle = (end + begin) / 2;
7505 anchor = (*block->anchors)[middle];
7506 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7507 end = middle;
7508 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7509 begin = middle + 1;
7510 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7511 end = middle;
7512 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7513 begin = middle + 1;
7514 else
7515 return anchor;
7518 /* Create a new anchor with a unique label. */
7519 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7520 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7521 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7522 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7524 /* Insert it at index BEGIN. */
7525 vec_safe_insert (block->anchors, begin, anchor);
7526 return anchor;
7529 /* Output the objects in BLOCK. */
7531 static void
7532 output_object_block (struct object_block *block)
7534 struct constant_descriptor_rtx *desc;
7535 unsigned int i;
7536 HOST_WIDE_INT offset;
7537 tree decl;
7538 rtx symbol;
7540 if (!block->objects)
7541 return;
7543 /* Switch to the section and make sure that the first byte is
7544 suitably aligned. */
7545 /* Special case VTV comdat sections similar to assemble_variable. */
7546 if (SECTION_STYLE (block->sect) == SECTION_NAMED
7547 && block->sect->named.name
7548 && (strcmp (block->sect->named.name, ".vtable_map_vars") == 0))
7549 handle_vtv_comdat_section (block->sect, block->sect->named.decl);
7550 else
7551 switch_to_section (block->sect);
7553 assemble_align (block->alignment);
7555 /* Define the values of all anchors relative to the current section
7556 position. */
7557 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7558 targetm.asm_out.output_anchor (symbol);
7560 /* Output the objects themselves. */
7561 offset = 0;
7562 FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7564 /* Move to the object's offset, padding with zeros if necessary. */
7565 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7566 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7567 if (CONSTANT_POOL_ADDRESS_P (symbol))
7569 desc = SYMBOL_REF_CONSTANT (symbol);
7570 /* Pass 1 for align as we have already laid out everything in the block.
7571 So aligning shouldn't be necessary. */
7572 output_constant_pool_1 (desc, 1);
7573 offset += GET_MODE_SIZE (desc->mode);
7575 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7577 HOST_WIDE_INT size;
7578 decl = SYMBOL_REF_DECL (symbol);
7579 assemble_constant_contents
7580 (DECL_INITIAL (decl), XSTR (symbol, 0), DECL_ALIGN (decl));
7582 size = get_constant_size (DECL_INITIAL (decl));
7583 offset += size;
7584 if ((flag_sanitize & SANITIZE_ADDRESS)
7585 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7586 && asan_protect_global (DECL_INITIAL (decl)))
7588 size = asan_red_zone_size (size);
7589 assemble_zeros (size);
7590 offset += size;
7593 else
7595 HOST_WIDE_INT size;
7596 decl = SYMBOL_REF_DECL (symbol);
7597 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7598 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7599 offset += size;
7600 if ((flag_sanitize & SANITIZE_ADDRESS)
7601 && asan_protect_global (decl))
7603 size = asan_red_zone_size (size);
7604 assemble_zeros (size);
7605 offset += size;
7611 /* A callback for qsort to compare object_blocks. */
7613 static int
7614 output_object_block_compare (const void *x, const void *y)
7616 object_block *p1 = *(object_block * const*)x;
7617 object_block *p2 = *(object_block * const*)y;
7619 if (p1->sect->common.flags & SECTION_NAMED
7620 && !(p2->sect->common.flags & SECTION_NAMED))
7621 return 1;
7623 if (!(p1->sect->common.flags & SECTION_NAMED)
7624 && p2->sect->common.flags & SECTION_NAMED)
7625 return -1;
7627 if (p1->sect->common.flags & SECTION_NAMED
7628 && p2->sect->common.flags & SECTION_NAMED)
7629 return strcmp (p1->sect->named.name, p2->sect->named.name);
7631 unsigned f1 = p1->sect->common.flags;
7632 unsigned f2 = p2->sect->common.flags;
7633 if (f1 == f2)
7634 return 0;
7635 return f1 < f2 ? -1 : 1;
7638 /* Output the definitions of all object_blocks. */
7640 void
7641 output_object_blocks (void)
7643 vec<object_block *, va_heap> v;
7644 v.create (object_block_htab->elements ());
7645 object_block *obj;
7646 hash_table<object_block_hasher>::iterator hi;
7648 FOR_EACH_HASH_TABLE_ELEMENT (*object_block_htab, obj, object_block *, hi)
7649 v.quick_push (obj);
7651 /* Sort them in order to output them in a deterministic manner,
7652 otherwise we may get .rodata sections in different orders with
7653 and without -g. */
7654 v.qsort (output_object_block_compare);
7655 unsigned i;
7656 FOR_EACH_VEC_ELT (v, i, obj)
7657 output_object_block (obj);
7659 v.release ();
7662 /* This function provides a possible implementation of the
7663 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7664 by -frecord-gcc-switches it creates a new mergeable, string section in the
7665 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7666 contains the switches in ASCII format.
7668 FIXME: This code does not correctly handle double quote characters
7669 that appear inside strings, (it strips them rather than preserving them).
7670 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7671 characters - instead it treats them as sub-string separators. Since
7672 we want to emit NUL strings terminators into the object file we have to use
7673 ASM_OUTPUT_SKIP. */
7676 elf_record_gcc_switches (print_switch_type type, const char * name)
7678 switch (type)
7680 case SWITCH_TYPE_PASSED:
7681 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7682 ASM_OUTPUT_SKIP (asm_out_file, HOST_WIDE_INT_1U);
7683 break;
7685 case SWITCH_TYPE_DESCRIPTIVE:
7686 if (name == NULL)
7688 /* Distinguish between invocations where name is NULL. */
7689 static bool started = false;
7691 if (!started)
7693 section * sec;
7695 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7696 SECTION_DEBUG
7697 | SECTION_MERGE
7698 | SECTION_STRINGS
7699 | (SECTION_ENTSIZE & 1),
7700 NULL);
7701 switch_to_section (sec);
7702 started = true;
7706 default:
7707 break;
7710 /* The return value is currently ignored by the caller, but must be 0.
7711 For -fverbose-asm the return value would be the number of characters
7712 emitted into the assembler file. */
7713 return 0;
7716 /* Emit text to declare externally defined symbols. It is needed to
7717 properly support non-default visibility. */
7718 void
7719 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7720 tree decl,
7721 const char *name ATTRIBUTE_UNUSED)
7723 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7724 set in order to avoid putting out names that are never really
7725 used. Always output visibility specified in the source. */
7726 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7727 && (DECL_VISIBILITY_SPECIFIED (decl)
7728 || targetm.binds_local_p (decl)))
7729 maybe_assemble_visibility (decl);
7732 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7734 void
7735 default_asm_output_source_filename (FILE *file, const char *name)
7737 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7738 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7739 #else
7740 fprintf (file, "\t.file\t");
7741 output_quoted_string (file, name);
7742 putc ('\n', file);
7743 #endif
7746 /* Output a file name in the form wanted by System V. */
7748 void
7749 output_file_directive (FILE *asm_file, const char *input_name)
7751 int len;
7752 const char *na;
7754 if (input_name == NULL)
7755 input_name = "<stdin>";
7756 else
7757 input_name = remap_debug_filename (input_name);
7759 len = strlen (input_name);
7760 na = input_name + len;
7762 /* NA gets INPUT_NAME sans directory names. */
7763 while (na > input_name)
7765 if (IS_DIR_SEPARATOR (na[-1]))
7766 break;
7767 na--;
7770 targetm.asm_out.output_source_filename (asm_file, na);
7773 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7774 EXP. */
7776 make_debug_expr_from_rtl (const_rtx exp)
7778 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7779 machine_mode mode = GET_MODE (exp);
7780 rtx dval;
7782 DECL_ARTIFICIAL (ddecl) = 1;
7783 if (REG_P (exp) && REG_EXPR (exp))
7784 type = TREE_TYPE (REG_EXPR (exp));
7785 else if (MEM_P (exp) && MEM_EXPR (exp))
7786 type = TREE_TYPE (MEM_EXPR (exp));
7787 else
7788 type = NULL_TREE;
7789 if (type && TYPE_MODE (type) == mode)
7790 TREE_TYPE (ddecl) = type;
7791 else
7792 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7793 SET_DECL_MODE (ddecl, mode);
7794 dval = gen_rtx_DEBUG_EXPR (mode);
7795 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7796 SET_DECL_RTL (ddecl, dval);
7797 return dval;
7800 #ifdef ELF_ASCII_ESCAPES
7801 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7803 void
7804 default_elf_asm_output_limited_string (FILE *f, const char *s)
7806 int escape;
7807 unsigned char c;
7809 fputs (STRING_ASM_OP, f);
7810 putc ('"', f);
7811 while (*s != '\0')
7813 c = *s;
7814 escape = ELF_ASCII_ESCAPES[c];
7815 switch (escape)
7817 case 0:
7818 putc (c, f);
7819 break;
7820 case 1:
7821 putc ('\\', f);
7822 putc ('0'+((c>>6)&7), f);
7823 putc ('0'+((c>>3)&7), f);
7824 putc ('0'+(c&7), f);
7825 break;
7826 default:
7827 putc ('\\', f);
7828 putc (escape, f);
7829 break;
7831 s++;
7833 putc ('\"', f);
7834 putc ('\n', f);
7837 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7839 void
7840 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7842 const char *limit = s + len;
7843 const char *last_null = NULL;
7844 unsigned bytes_in_chunk = 0;
7845 unsigned char c;
7846 int escape;
7848 for (; s < limit; s++)
7850 const char *p;
7852 if (bytes_in_chunk >= 60)
7854 putc ('\"', f);
7855 putc ('\n', f);
7856 bytes_in_chunk = 0;
7859 if (s > last_null)
7861 for (p = s; p < limit && *p != '\0'; p++)
7862 continue;
7863 last_null = p;
7865 else
7866 p = last_null;
7868 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7870 if (bytes_in_chunk > 0)
7872 putc ('\"', f);
7873 putc ('\n', f);
7874 bytes_in_chunk = 0;
7877 default_elf_asm_output_limited_string (f, s);
7878 s = p;
7880 else
7882 if (bytes_in_chunk == 0)
7883 fputs (ASCII_DATA_ASM_OP "\"", f);
7885 c = *s;
7886 escape = ELF_ASCII_ESCAPES[c];
7887 switch (escape)
7889 case 0:
7890 putc (c, f);
7891 bytes_in_chunk++;
7892 break;
7893 case 1:
7894 putc ('\\', f);
7895 putc ('0'+((c>>6)&7), f);
7896 putc ('0'+((c>>3)&7), f);
7897 putc ('0'+(c&7), f);
7898 bytes_in_chunk += 4;
7899 break;
7900 default:
7901 putc ('\\', f);
7902 putc (escape, f);
7903 bytes_in_chunk += 2;
7904 break;
7910 if (bytes_in_chunk > 0)
7912 putc ('\"', f);
7913 putc ('\n', f);
7916 #endif
7918 static GTY(()) section *elf_init_array_section;
7919 static GTY(()) section *elf_fini_array_section;
7921 static section *
7922 get_elf_initfini_array_priority_section (int priority,
7923 bool constructor_p)
7925 section *sec;
7926 if (priority != DEFAULT_INIT_PRIORITY)
7928 char buf[18];
7929 sprintf (buf, "%s.%.5u",
7930 constructor_p ? ".init_array" : ".fini_array",
7931 priority);
7932 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7934 else
7936 if (constructor_p)
7938 if (elf_init_array_section == NULL)
7939 elf_init_array_section
7940 = get_section (".init_array",
7941 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7942 sec = elf_init_array_section;
7944 else
7946 if (elf_fini_array_section == NULL)
7947 elf_fini_array_section
7948 = get_section (".fini_array",
7949 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7950 sec = elf_fini_array_section;
7953 return sec;
7956 /* Use .init_array section for constructors. */
7958 void
7959 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7961 section *sec = get_elf_initfini_array_priority_section (priority,
7962 true);
7963 assemble_addr_to_section (symbol, sec);
7966 /* Use .fini_array section for destructors. */
7968 void
7969 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7971 section *sec = get_elf_initfini_array_priority_section (priority,
7972 false);
7973 assemble_addr_to_section (symbol, sec);
7976 /* Default TARGET_ASM_OUTPUT_IDENT hook.
7978 This is a bit of a cheat. The real default is a no-op, but this
7979 hook is the default for all targets with a .ident directive. */
7981 void
7982 default_asm_output_ident_directive (const char *ident_str)
7984 const char *ident_asm_op = "\t.ident\t";
7986 /* If we are still in the front end, do not write out the string
7987 to asm_out_file. Instead, add a fake top-level asm statement.
7988 This allows the front ends to use this hook without actually
7989 writing to asm_out_file, to handle #ident or Pragma Ident. */
7990 if (symtab->state == PARSING)
7992 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
7993 symtab->finalize_toplevel_asm (build_string (strlen (buf), buf));
7995 else
7996 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
8000 /* This function ensures that vtable_map variables are not only
8001 in the comdat section, but that each variable has its own unique
8002 comdat name. Without this the variables end up in the same section
8003 with a single comdat name.
8005 FIXME: resolve_unique_section needs to deal better with
8006 decls with both DECL_SECTION_NAME and DECL_ONE_ONLY. Once
8007 that is fixed, this if-else statement can be replaced with
8008 a single call to "switch_to_section (sect)". */
8010 static void
8011 handle_vtv_comdat_section (section *sect, const_tree decl ATTRIBUTE_UNUSED)
8013 #if defined (OBJECT_FORMAT_ELF)
8014 targetm.asm_out.named_section (sect->named.name,
8015 sect->named.common.flags
8016 | SECTION_LINKONCE,
8017 DECL_NAME (decl));
8018 in_section = sect;
8019 #else
8020 /* Neither OBJECT_FORMAT_PE, nor OBJECT_FORMAT_COFF is set here.
8021 Therefore the following check is used.
8022 In case a the target is PE or COFF a comdat group section
8023 is created, e.g. .vtable_map_vars$foo. The linker places
8024 everything in .vtable_map_vars at the end.
8026 A fix could be made in
8027 gcc/config/i386/winnt.c: i386_pe_unique_section. */
8028 if (TARGET_PECOFF)
8030 char *name;
8032 if (TREE_CODE (DECL_NAME (decl)) == IDENTIFIER_NODE)
8033 name = ACONCAT ((sect->named.name, "$",
8034 IDENTIFIER_POINTER (DECL_NAME (decl)), NULL));
8035 else
8036 name = ACONCAT ((sect->named.name, "$",
8037 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (DECL_NAME (decl))),
8038 NULL));
8040 targetm.asm_out.named_section (name,
8041 sect->named.common.flags
8042 | SECTION_LINKONCE,
8043 DECL_NAME (decl));
8044 in_section = sect;
8046 else
8047 switch_to_section (sect);
8048 #endif
8051 #include "gt-varasm.h"