Make mode_for_size return an opt_mode
[official-gcc.git] / gcc / varasm.c
blobf2a12f0495f229ac608cc21cf88aae980eaea416
1 /* Output variables, constants and external declarations, for GNU compiler.
2 Copyright (C) 1987-2017 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
21 /* This file handles generation of all the assembler code
22 *except* the instructions of a function.
23 This includes declarations of variables and their initial values.
25 We also output the assembler code for constants stored in memory
26 and are responsible for combining constants with the same value. */
28 #include "config.h"
29 #include "system.h"
30 #include "coretypes.h"
31 #include "backend.h"
32 #include "target.h"
33 #include "rtl.h"
34 #include "tree.h"
35 #include "predict.h"
36 #include "memmodel.h"
37 #include "tm_p.h"
38 #include "stringpool.h"
39 #include "regs.h"
40 #include "emit-rtl.h"
41 #include "cgraph.h"
42 #include "diagnostic-core.h"
43 #include "fold-const.h"
44 #include "stor-layout.h"
45 #include "varasm.h"
46 #include "flags.h"
47 #include "stmt.h"
48 #include "expr.h"
49 #include "expmed.h"
50 #include "output.h"
51 #include "langhooks.h"
52 #include "debug.h"
53 #include "common/common-target.h"
54 #include "stringpool.h"
55 #include "attribs.h"
56 #include "asan.h"
57 #include "rtl-iter.h"
59 #ifdef XCOFF_DEBUGGING_INFO
60 #include "xcoffout.h" /* Needed for external data declarations. */
61 #endif
63 /* The (assembler) name of the first globally-visible object output. */
64 extern GTY(()) const char *first_global_object_name;
65 extern GTY(()) const char *weak_global_object_name;
67 const char *first_global_object_name;
68 const char *weak_global_object_name;
70 struct addr_const;
71 struct constant_descriptor_rtx;
72 struct rtx_constant_pool;
74 #define n_deferred_constants (crtl->varasm.deferred_constants)
76 /* Number for making the label on the next
77 constant that is stored in memory. */
79 static GTY(()) int const_labelno;
81 /* Carry information from ASM_DECLARE_OBJECT_NAME
82 to ASM_FINISH_DECLARE_OBJECT. */
84 int size_directive_output;
86 /* The last decl for which assemble_variable was called,
87 if it did ASM_DECLARE_OBJECT_NAME.
88 If the last call to assemble_variable didn't do that,
89 this holds 0. */
91 tree last_assemble_variable_decl;
93 /* The following global variable indicates if the first basic block
94 in a function belongs to the cold partition or not. */
96 bool first_function_block_is_cold;
98 /* Whether we saw any functions with no_split_stack. */
100 static bool saw_no_split_stack;
102 static const char *strip_reg_name (const char *);
103 static int contains_pointers_p (tree);
104 #ifdef ASM_OUTPUT_EXTERNAL
105 static bool incorporeal_function_p (tree);
106 #endif
107 static void decode_addr_const (tree, struct addr_const *);
108 static hashval_t const_hash_1 (const tree);
109 static int compare_constant (const tree, const tree);
110 static void output_constant_def_contents (rtx);
111 static void output_addressed_constants (tree);
112 static unsigned HOST_WIDE_INT output_constant (tree, unsigned HOST_WIDE_INT,
113 unsigned int, bool);
114 static void globalize_decl (tree);
115 static bool decl_readonly_section_1 (enum section_category);
116 #ifdef BSS_SECTION_ASM_OP
117 #ifdef ASM_OUTPUT_ALIGNED_BSS
118 static void asm_output_aligned_bss (FILE *, tree, const char *,
119 unsigned HOST_WIDE_INT, int)
120 ATTRIBUTE_UNUSED;
121 #endif
122 #endif /* BSS_SECTION_ASM_OP */
123 static void mark_weak (tree);
124 static void output_constant_pool (const char *, tree);
125 static void handle_vtv_comdat_section (section *, const_tree);
127 /* Well-known sections, each one associated with some sort of *_ASM_OP. */
128 section *text_section;
129 section *data_section;
130 section *readonly_data_section;
131 section *sdata_section;
132 section *ctors_section;
133 section *dtors_section;
134 section *bss_section;
135 section *sbss_section;
137 /* Various forms of common section. All are guaranteed to be nonnull. */
138 section *tls_comm_section;
139 section *comm_section;
140 section *lcomm_section;
142 /* A SECTION_NOSWITCH section used for declaring global BSS variables.
143 May be null. */
144 section *bss_noswitch_section;
146 /* The section that holds the main exception table, when known. The section
147 is set either by the target's init_sections hook or by the first call to
148 switch_to_exception_section. */
149 section *exception_section;
151 /* The section that holds the DWARF2 frame unwind information, when known.
152 The section is set either by the target's init_sections hook or by the
153 first call to switch_to_eh_frame_section. */
154 section *eh_frame_section;
156 /* asm_out_file's current section. This is NULL if no section has yet
157 been selected or if we lose track of what the current section is. */
158 section *in_section;
160 /* True if code for the current function is currently being directed
161 at the cold section. */
162 bool in_cold_section_p;
164 /* The following global holds the "function name" for the code in the
165 cold section of a function, if hot/cold function splitting is enabled
166 and there was actually code that went into the cold section. A
167 pseudo function name is needed for the cold section of code for some
168 debugging tools that perform symbolization. */
169 tree cold_function_name = NULL_TREE;
171 /* A linked list of all the unnamed sections. */
172 static GTY(()) section *unnamed_sections;
174 /* Return a nonzero value if DECL has a section attribute. */
175 #define IN_NAMED_SECTION(DECL) \
176 (VAR_OR_FUNCTION_DECL_P (DECL) && DECL_SECTION_NAME (DECL) != NULL)
178 struct section_hasher : ggc_ptr_hash<section>
180 typedef const char *compare_type;
182 static hashval_t hash (section *);
183 static bool equal (section *, const char *);
186 /* Hash table of named sections. */
187 static GTY(()) hash_table<section_hasher> *section_htab;
189 struct object_block_hasher : ggc_ptr_hash<object_block>
191 typedef const section *compare_type;
193 static hashval_t hash (object_block *);
194 static bool equal (object_block *, const section *);
197 /* A table of object_blocks, indexed by section. */
198 static GTY(()) hash_table<object_block_hasher> *object_block_htab;
200 /* The next number to use for internal anchor labels. */
201 static GTY(()) int anchor_labelno;
203 /* A pool of constants that can be shared between functions. */
204 static GTY(()) struct rtx_constant_pool *shared_constant_pool;
206 /* Helper routines for maintaining section_htab. */
208 bool
209 section_hasher::equal (section *old, const char *new_name)
211 return strcmp (old->named.name, new_name) == 0;
214 hashval_t
215 section_hasher::hash (section *old)
217 return htab_hash_string (old->named.name);
220 /* Return a hash value for section SECT. */
222 static hashval_t
223 hash_section (section *sect)
225 if (sect->common.flags & SECTION_NAMED)
226 return htab_hash_string (sect->named.name);
227 return sect->common.flags;
230 /* Helper routines for maintaining object_block_htab. */
232 inline bool
233 object_block_hasher::equal (object_block *old, const section *new_section)
235 return old->sect == new_section;
238 hashval_t
239 object_block_hasher::hash (object_block *old)
241 return hash_section (old->sect);
244 /* Return a new unnamed section with the given fields. */
246 section *
247 get_unnamed_section (unsigned int flags, void (*callback) (const void *),
248 const void *data)
250 section *sect;
252 sect = ggc_alloc<section> ();
253 sect->unnamed.common.flags = flags | SECTION_UNNAMED;
254 sect->unnamed.callback = callback;
255 sect->unnamed.data = data;
256 sect->unnamed.next = unnamed_sections;
258 unnamed_sections = sect;
259 return sect;
262 /* Return a SECTION_NOSWITCH section with the given fields. */
264 static section *
265 get_noswitch_section (unsigned int flags, noswitch_section_callback callback)
267 section *sect;
269 sect = ggc_alloc<section> ();
270 sect->noswitch.common.flags = flags | SECTION_NOSWITCH;
271 sect->noswitch.callback = callback;
273 return sect;
276 /* Return the named section structure associated with NAME. Create
277 a new section with the given fields if no such structure exists. */
279 section *
280 get_section (const char *name, unsigned int flags, tree decl)
282 section *sect, **slot;
284 slot = section_htab->find_slot_with_hash (name, htab_hash_string (name),
285 INSERT);
286 flags |= SECTION_NAMED;
287 if (*slot == NULL)
289 sect = ggc_alloc<section> ();
290 sect->named.common.flags = flags;
291 sect->named.name = ggc_strdup (name);
292 sect->named.decl = decl;
293 *slot = sect;
295 else
297 sect = *slot;
298 if ((sect->common.flags & ~SECTION_DECLARED) != flags
299 && ((sect->common.flags | flags) & SECTION_OVERRIDE) == 0)
301 /* It is fine if one of the section flags is
302 SECTION_WRITE | SECTION_RELRO and the other has none of these
303 flags (i.e. read-only) in named sections and either the
304 section hasn't been declared yet or has been declared as writable.
305 In that case just make sure the resulting flags are
306 SECTION_WRITE | SECTION_RELRO, ie. writable only because of
307 relocations. */
308 if (((sect->common.flags ^ flags) & (SECTION_WRITE | SECTION_RELRO))
309 == (SECTION_WRITE | SECTION_RELRO)
310 && (sect->common.flags
311 & ~(SECTION_DECLARED | SECTION_WRITE | SECTION_RELRO))
312 == (flags & ~(SECTION_WRITE | SECTION_RELRO))
313 && ((sect->common.flags & SECTION_DECLARED) == 0
314 || (sect->common.flags & SECTION_WRITE)))
316 sect->common.flags |= (SECTION_WRITE | SECTION_RELRO);
317 return sect;
319 /* Sanity check user variables for flag changes. */
320 if (sect->named.decl != NULL
321 && DECL_P (sect->named.decl)
322 && decl != sect->named.decl)
324 if (decl != NULL && DECL_P (decl))
325 error ("%+qD causes a section type conflict with %qD",
326 decl, sect->named.decl);
327 else
328 error ("section type conflict with %qD", sect->named.decl);
329 inform (DECL_SOURCE_LOCATION (sect->named.decl),
330 "%qD was declared here", sect->named.decl);
332 else if (decl != NULL && DECL_P (decl))
333 error ("%+qD causes a section type conflict", decl);
334 else
335 error ("section type conflict");
336 /* Make sure we don't error about one section multiple times. */
337 sect->common.flags |= SECTION_OVERRIDE;
340 return sect;
343 /* Return true if the current compilation mode benefits from having
344 objects grouped into blocks. */
346 static bool
347 use_object_blocks_p (void)
349 return flag_section_anchors;
352 /* Return the object_block structure for section SECT. Create a new
353 structure if we haven't created one already. Return null if SECT
354 itself is null. */
356 static struct object_block *
357 get_block_for_section (section *sect)
359 struct object_block *block;
361 if (sect == NULL)
362 return NULL;
364 object_block **slot
365 = object_block_htab->find_slot_with_hash (sect, hash_section (sect),
366 INSERT);
367 block = *slot;
368 if (block == NULL)
370 block = ggc_cleared_alloc<object_block> ();
371 block->sect = sect;
372 *slot = block;
374 return block;
377 /* Create a symbol with label LABEL and place it at byte offset
378 OFFSET in BLOCK. OFFSET can be negative if the symbol's offset
379 is not yet known. LABEL must be a garbage-collected string. */
381 static rtx
382 create_block_symbol (const char *label, struct object_block *block,
383 HOST_WIDE_INT offset)
385 rtx symbol;
386 unsigned int size;
388 /* Create the extended SYMBOL_REF. */
389 size = RTX_HDR_SIZE + sizeof (struct block_symbol);
390 symbol = (rtx) ggc_internal_alloc (size);
392 /* Initialize the normal SYMBOL_REF fields. */
393 memset (symbol, 0, size);
394 PUT_CODE (symbol, SYMBOL_REF);
395 PUT_MODE (symbol, Pmode);
396 XSTR (symbol, 0) = label;
397 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_HAS_BLOCK_INFO;
399 /* Initialize the block_symbol stuff. */
400 SYMBOL_REF_BLOCK (symbol) = block;
401 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
403 return symbol;
406 /* Return a section with a particular name and with whatever SECTION_*
407 flags section_type_flags deems appropriate. The name of the section
408 is taken from NAME if nonnull, otherwise it is taken from DECL's
409 DECL_SECTION_NAME. DECL is the decl associated with the section
410 (see the section comment for details) and RELOC is as for
411 section_type_flags. */
413 section *
414 get_named_section (tree decl, const char *name, int reloc)
416 unsigned int flags;
418 if (name == NULL)
420 gcc_assert (decl && DECL_P (decl) && DECL_SECTION_NAME (decl));
421 name = DECL_SECTION_NAME (decl);
424 flags = targetm.section_type_flags (decl, name, reloc);
425 return get_section (name, flags, decl);
428 /* Worker for resolve_unique_section. */
430 static bool
431 set_implicit_section (struct symtab_node *n, void *data ATTRIBUTE_UNUSED)
433 n->implicit_section = true;
434 return false;
437 /* If required, set DECL_SECTION_NAME to a unique name. */
439 void
440 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
441 int flag_function_or_data_sections)
443 if (DECL_SECTION_NAME (decl) == NULL
444 && targetm_common.have_named_sections
445 && (flag_function_or_data_sections
446 || DECL_COMDAT_GROUP (decl)))
448 targetm.asm_out.unique_section (decl, reloc);
449 if (DECL_SECTION_NAME (decl))
450 symtab_node::get (decl)->call_for_symbol_and_aliases
451 (set_implicit_section, NULL, true);
455 #ifdef BSS_SECTION_ASM_OP
457 #ifdef ASM_OUTPUT_ALIGNED_BSS
459 /* Utility function for targets to use in implementing
460 ASM_OUTPUT_ALIGNED_BSS.
461 ??? It is believed that this function will work in most cases so such
462 support is localized here. */
464 static void
465 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
466 const char *name, unsigned HOST_WIDE_INT size,
467 int align)
469 switch_to_section (bss_section);
470 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
471 #ifdef ASM_DECLARE_OBJECT_NAME
472 last_assemble_variable_decl = decl;
473 ASM_DECLARE_OBJECT_NAME (file, name, decl);
474 #else
475 /* Standard thing is just output label for the object. */
476 ASM_OUTPUT_LABEL (file, name);
477 #endif /* ASM_DECLARE_OBJECT_NAME */
478 ASM_OUTPUT_SKIP (file, size ? size : 1);
481 #endif
483 #endif /* BSS_SECTION_ASM_OP */
485 #ifndef USE_SELECT_SECTION_FOR_FUNCTIONS
486 /* Return the hot section for function DECL. Return text_section for
487 null DECLs. */
489 static section *
490 hot_function_section (tree decl)
492 if (decl != NULL_TREE
493 && DECL_SECTION_NAME (decl) != NULL
494 && targetm_common.have_named_sections)
495 return get_named_section (decl, NULL, 0);
496 else
497 return text_section;
499 #endif
501 /* Return section for TEXT_SECTION_NAME if DECL or DECL_SECTION_NAME (DECL)
502 is NULL.
504 When DECL_SECTION_NAME is non-NULL and it is implicit section and
505 NAMED_SECTION_SUFFIX is non-NULL, then produce section called
506 concatenate the name with NAMED_SECTION_SUFFIX.
507 Otherwise produce "TEXT_SECTION_NAME.IMPLICIT_NAME". */
509 section *
510 get_named_text_section (tree decl,
511 const char *text_section_name,
512 const char *named_section_suffix)
514 if (decl && DECL_SECTION_NAME (decl))
516 if (named_section_suffix)
518 const char *dsn = DECL_SECTION_NAME (decl);
519 const char *stripped_name;
520 char *name, *buffer;
522 name = (char *) alloca (strlen (dsn) + 1);
523 memcpy (name, dsn,
524 strlen (dsn) + 1);
526 stripped_name = targetm.strip_name_encoding (name);
528 buffer = ACONCAT ((stripped_name, named_section_suffix, NULL));
529 return get_named_section (decl, buffer, 0);
531 else if (symtab_node::get (decl)->implicit_section)
533 const char *name;
535 /* Do not try to split gnu_linkonce functions. This gets somewhat
536 slipperly. */
537 if (DECL_COMDAT_GROUP (decl) && !HAVE_COMDAT_GROUP)
538 return NULL;
539 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
540 name = targetm.strip_name_encoding (name);
541 return get_named_section (decl, ACONCAT ((text_section_name, ".",
542 name, NULL)), 0);
544 else
545 return NULL;
547 return get_named_section (decl, text_section_name, 0);
550 /* Choose named function section based on its frequency. */
552 section *
553 default_function_section (tree decl, enum node_frequency freq,
554 bool startup, bool exit)
556 #if defined HAVE_LD_EH_GC_SECTIONS && defined HAVE_LD_EH_GC_SECTIONS_BUG
557 /* Old GNU linkers have buggy --gc-section support, which sometimes
558 results in .gcc_except_table* sections being garbage collected. */
559 if (decl
560 && symtab_node::get (decl)->implicit_section)
561 return NULL;
562 #endif
564 if (!flag_reorder_functions
565 || !targetm_common.have_named_sections)
566 return NULL;
567 /* Startup code should go to startup subsection unless it is
568 unlikely executed (this happens especially with function splitting
569 where we can split away unnecessary parts of static constructors. */
570 if (startup && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
572 /* If we do have a profile or(and) LTO phase is executed, we do not need
573 these ELF section. */
574 if (!in_lto_p || !flag_profile_values)
575 return get_named_text_section (decl, ".text.startup", NULL);
576 else
577 return NULL;
580 /* Similarly for exit. */
581 if (exit && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
582 return get_named_text_section (decl, ".text.exit", NULL);
584 /* Group cold functions together, similarly for hot code. */
585 switch (freq)
587 case NODE_FREQUENCY_UNLIKELY_EXECUTED:
588 return get_named_text_section (decl, ".text.unlikely", NULL);
589 case NODE_FREQUENCY_HOT:
590 /* If we do have a profile or(and) LTO phase is executed, we do not need
591 these ELF section. */
592 if (!in_lto_p || !flag_profile_values)
593 return get_named_text_section (decl, ".text.hot", NULL);
594 /* FALLTHRU */
595 default:
596 return NULL;
600 /* Return the section for function DECL.
602 If DECL is NULL_TREE, return the text section. We can be passed
603 NULL_TREE under some circumstances by dbxout.c at least.
605 If FORCE_COLD is true, return cold function section ignoring
606 the frequency info of cgraph_node. */
608 static section *
609 function_section_1 (tree decl, bool force_cold)
611 section *section = NULL;
612 enum node_frequency freq = NODE_FREQUENCY_NORMAL;
613 bool startup = false, exit = false;
615 if (decl)
617 struct cgraph_node *node = cgraph_node::get (decl);
619 if (node)
621 freq = node->frequency;
622 startup = node->only_called_at_startup;
623 exit = node->only_called_at_exit;
626 if (force_cold)
627 freq = NODE_FREQUENCY_UNLIKELY_EXECUTED;
629 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
630 if (decl != NULL_TREE
631 && DECL_SECTION_NAME (decl) != NULL)
633 if (targetm.asm_out.function_section)
634 section = targetm.asm_out.function_section (decl, freq,
635 startup, exit);
636 if (section)
637 return section;
638 return get_named_section (decl, NULL, 0);
640 else
641 return targetm.asm_out.select_section
642 (decl, freq == NODE_FREQUENCY_UNLIKELY_EXECUTED,
643 symtab_node::get (decl)->definition_alignment ());
644 #else
645 if (targetm.asm_out.function_section)
646 section = targetm.asm_out.function_section (decl, freq, startup, exit);
647 if (section)
648 return section;
649 return hot_function_section (decl);
650 #endif
653 /* Return the section for function DECL.
655 If DECL is NULL_TREE, return the text section. We can be passed
656 NULL_TREE under some circumstances by dbxout.c at least. */
658 section *
659 function_section (tree decl)
661 /* Handle cases where function splitting code decides
662 to put function entry point into unlikely executed section
663 despite the fact that the function itself is not cold
664 (i.e. it is called rarely but contains a hot loop that is
665 better to live in hot subsection for the code locality). */
666 return function_section_1 (decl,
667 first_function_block_is_cold);
670 /* Return the section for the current function, take IN_COLD_SECTION_P
671 into account. */
673 section *
674 current_function_section (void)
676 return function_section_1 (current_function_decl, in_cold_section_p);
679 /* Tell assembler to switch to unlikely-to-be-executed text section. */
681 section *
682 unlikely_text_section (void)
684 return function_section_1 (current_function_decl, true);
687 /* When called within a function context, return true if the function
688 has been assigned a cold text section and if SECT is that section.
689 When called outside a function context, return true if SECT is the
690 default cold section. */
692 bool
693 unlikely_text_section_p (section *sect)
695 return sect == function_section_1 (current_function_decl, true);
698 /* Return the read-only data section associated with function DECL. */
700 section *
701 default_function_rodata_section (tree decl)
703 if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
705 const char *name = DECL_SECTION_NAME (decl);
707 if (DECL_COMDAT_GROUP (decl) && HAVE_COMDAT_GROUP)
709 const char *dot;
710 size_t len;
711 char* rname;
713 dot = strchr (name + 1, '.');
714 if (!dot)
715 dot = name;
716 len = strlen (dot) + 8;
717 rname = (char *) alloca (len);
719 strcpy (rname, ".rodata");
720 strcat (rname, dot);
721 return get_section (rname, SECTION_LINKONCE, decl);
723 /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo. */
724 else if (DECL_COMDAT_GROUP (decl)
725 && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
727 size_t len = strlen (name) + 1;
728 char *rname = (char *) alloca (len);
730 memcpy (rname, name, len);
731 rname[14] = 'r';
732 return get_section (rname, SECTION_LINKONCE, decl);
734 /* For .text.foo we want to use .rodata.foo. */
735 else if (flag_function_sections && flag_data_sections
736 && strncmp (name, ".text.", 6) == 0)
738 size_t len = strlen (name) + 1;
739 char *rname = (char *) alloca (len + 2);
741 memcpy (rname, ".rodata", 7);
742 memcpy (rname + 7, name + 5, len - 5);
743 return get_section (rname, 0, decl);
747 return readonly_data_section;
750 /* Return the read-only data section associated with function DECL
751 for targets where that section should be always the single
752 readonly data section. */
754 section *
755 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
757 return readonly_data_section;
760 /* A subroutine of mergeable_string_section and mergeable_constant_section. */
762 static const char *
763 function_mergeable_rodata_prefix (void)
765 section *s = targetm.asm_out.function_rodata_section (current_function_decl);
766 if (SECTION_STYLE (s) == SECTION_NAMED)
767 return s->named.name;
768 else
769 return targetm.asm_out.mergeable_rodata_prefix;
772 /* Return the section to use for string merging. */
774 static section *
775 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
776 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
777 unsigned int flags ATTRIBUTE_UNUSED)
779 HOST_WIDE_INT len;
781 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
782 && TREE_CODE (decl) == STRING_CST
783 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
784 && align <= 256
785 && (len = int_size_in_bytes (TREE_TYPE (decl))) > 0
786 && TREE_STRING_LENGTH (decl) >= len)
788 scalar_int_mode mode;
789 unsigned int modesize;
790 const char *str;
791 HOST_WIDE_INT i;
792 int j, unit;
793 const char *prefix = function_mergeable_rodata_prefix ();
794 char *name = (char *) alloca (strlen (prefix) + 30);
796 mode = SCALAR_INT_TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
797 modesize = GET_MODE_BITSIZE (mode);
798 if (modesize >= 8 && modesize <= 256
799 && (modesize & (modesize - 1)) == 0)
801 if (align < modesize)
802 align = modesize;
804 str = TREE_STRING_POINTER (decl);
805 unit = GET_MODE_SIZE (mode);
807 /* Check for embedded NUL characters. */
808 for (i = 0; i < len; i += unit)
810 for (j = 0; j < unit; j++)
811 if (str[i + j] != '\0')
812 break;
813 if (j == unit)
814 break;
816 if (i == len - unit)
818 sprintf (name, "%s.str%d.%d", prefix,
819 modesize / 8, (int) (align / 8));
820 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
821 return get_section (name, flags, NULL);
826 return readonly_data_section;
829 /* Return the section to use for constant merging. */
831 section *
832 mergeable_constant_section (machine_mode mode ATTRIBUTE_UNUSED,
833 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
834 unsigned int flags ATTRIBUTE_UNUSED)
836 unsigned int modesize = GET_MODE_BITSIZE (mode);
838 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
839 && mode != VOIDmode
840 && mode != BLKmode
841 && modesize <= align
842 && align >= 8
843 && align <= 256
844 && (align & (align - 1)) == 0)
846 const char *prefix = function_mergeable_rodata_prefix ();
847 char *name = (char *) alloca (strlen (prefix) + 30);
849 sprintf (name, "%s.cst%d", prefix, (int) (align / 8));
850 flags |= (align / 8) | SECTION_MERGE;
851 return get_section (name, flags, NULL);
853 return readonly_data_section;
856 /* Given NAME, a putative register name, discard any customary prefixes. */
858 static const char *
859 strip_reg_name (const char *name)
861 #ifdef REGISTER_PREFIX
862 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
863 name += strlen (REGISTER_PREFIX);
864 #endif
865 if (name[0] == '%' || name[0] == '#')
866 name++;
867 return name;
870 /* The user has asked for a DECL to have a particular name. Set (or
871 change) it in such a way that we don't prefix an underscore to
872 it. */
873 void
874 set_user_assembler_name (tree decl, const char *name)
876 char *starred = (char *) alloca (strlen (name) + 2);
877 starred[0] = '*';
878 strcpy (starred + 1, name);
879 symtab->change_decl_assembler_name (decl, get_identifier (starred));
880 SET_DECL_RTL (decl, NULL_RTX);
883 /* Decode an `asm' spec for a declaration as a register name.
884 Return the register number, or -1 if nothing specified,
885 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
886 or -3 if ASMSPEC is `cc' and is not recognized,
887 or -4 if ASMSPEC is `memory' and is not recognized.
888 Accept an exact spelling or a decimal number.
889 Prefixes such as % are optional. */
892 decode_reg_name_and_count (const char *asmspec, int *pnregs)
894 /* Presume just one register is clobbered. */
895 *pnregs = 1;
897 if (asmspec != 0)
899 int i;
901 /* Get rid of confusing prefixes. */
902 asmspec = strip_reg_name (asmspec);
904 /* Allow a decimal number as a "register name". */
905 for (i = strlen (asmspec) - 1; i >= 0; i--)
906 if (! ISDIGIT (asmspec[i]))
907 break;
908 if (asmspec[0] != 0 && i < 0)
910 i = atoi (asmspec);
911 if (i < FIRST_PSEUDO_REGISTER && i >= 0 && reg_names[i][0])
912 return i;
913 else
914 return -2;
917 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
918 if (reg_names[i][0]
919 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
920 return i;
922 #ifdef OVERLAPPING_REGISTER_NAMES
924 static const struct
926 const char *const name;
927 const int number;
928 const int nregs;
929 } table[] = OVERLAPPING_REGISTER_NAMES;
931 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
932 if (table[i].name[0]
933 && ! strcmp (asmspec, table[i].name))
935 *pnregs = table[i].nregs;
936 return table[i].number;
939 #endif /* OVERLAPPING_REGISTER_NAMES */
941 #ifdef ADDITIONAL_REGISTER_NAMES
943 static const struct { const char *const name; const int number; } table[]
944 = ADDITIONAL_REGISTER_NAMES;
946 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
947 if (table[i].name[0]
948 && ! strcmp (asmspec, table[i].name)
949 && reg_names[table[i].number][0])
950 return table[i].number;
952 #endif /* ADDITIONAL_REGISTER_NAMES */
954 if (!strcmp (asmspec, "memory"))
955 return -4;
957 if (!strcmp (asmspec, "cc"))
958 return -3;
960 return -2;
963 return -1;
967 decode_reg_name (const char *name)
969 int count;
970 return decode_reg_name_and_count (name, &count);
974 /* Return true if DECL's initializer is suitable for a BSS section. */
976 bool
977 bss_initializer_p (const_tree decl)
979 /* Do not put constants into the .bss section, they belong in a readonly
980 section. */
981 return (!TREE_READONLY (decl)
982 && (DECL_INITIAL (decl) == NULL
983 /* In LTO we have no errors in program; error_mark_node is used
984 to mark offlined constructors. */
985 || (DECL_INITIAL (decl) == error_mark_node
986 && !in_lto_p)
987 || (flag_zero_initialized_in_bss
988 && initializer_zerop (DECL_INITIAL (decl)))));
991 /* Compute the alignment of variable specified by DECL.
992 DONT_OUTPUT_DATA is from assemble_variable. */
994 void
995 align_variable (tree decl, bool dont_output_data)
997 unsigned int align = DECL_ALIGN (decl);
999 /* In the case for initialing an array whose length isn't specified,
1000 where we have not yet been able to do the layout,
1001 figure out the proper alignment now. */
1002 if (dont_output_data && DECL_SIZE (decl) == 0
1003 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
1004 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
1006 /* Some object file formats have a maximum alignment which they support.
1007 In particular, a.out format supports a maximum alignment of 4. */
1008 if (align > MAX_OFILE_ALIGNMENT)
1010 error ("alignment of %q+D is greater than maximum object "
1011 "file alignment %d", decl,
1012 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
1013 align = MAX_OFILE_ALIGNMENT;
1016 if (! DECL_USER_ALIGN (decl))
1018 #ifdef DATA_ABI_ALIGNMENT
1019 unsigned int data_abi_align
1020 = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1021 /* For backwards compatibility, don't assume the ABI alignment for
1022 TLS variables. */
1023 if (! DECL_THREAD_LOCAL_P (decl) || data_abi_align <= BITS_PER_WORD)
1024 align = data_abi_align;
1025 #endif
1027 /* On some machines, it is good to increase alignment sometimes.
1028 But as DECL_ALIGN is used both for actually emitting the variable
1029 and for code accessing the variable as guaranteed alignment, we
1030 can only increase the alignment if it is a performance optimization
1031 if the references to it must bind to the current definition. */
1032 if (decl_binds_to_current_def_p (decl)
1033 && !DECL_VIRTUAL_P (decl))
1035 #ifdef DATA_ALIGNMENT
1036 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1037 /* Don't increase alignment too much for TLS variables - TLS space
1038 is too precious. */
1039 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1040 align = data_align;
1041 #endif
1042 if (DECL_INITIAL (decl) != 0
1043 /* In LTO we have no errors in program; error_mark_node is used
1044 to mark offlined constructors. */
1045 && (in_lto_p || DECL_INITIAL (decl) != error_mark_node))
1047 unsigned int const_align
1048 = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
1049 /* Don't increase alignment too much for TLS variables - TLS
1050 space is too precious. */
1051 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1052 align = const_align;
1057 /* Reset the alignment in case we have made it tighter, so we can benefit
1058 from it in get_pointer_alignment. */
1059 SET_DECL_ALIGN (decl, align);
1062 /* Return DECL_ALIGN (decl), possibly increased for optimization purposes
1063 beyond what align_variable returned. */
1065 static unsigned int
1066 get_variable_align (tree decl)
1068 unsigned int align = DECL_ALIGN (decl);
1070 /* For user aligned vars or static vars align_variable already did
1071 everything. */
1072 if (DECL_USER_ALIGN (decl) || !TREE_PUBLIC (decl))
1073 return align;
1075 #ifdef DATA_ABI_ALIGNMENT
1076 if (DECL_THREAD_LOCAL_P (decl))
1077 align = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1078 #endif
1080 /* For decls that bind to the current definition, align_variable
1081 did also everything, except for not assuming ABI required alignment
1082 of TLS variables. For other vars, increase the alignment here
1083 as an optimization. */
1084 if (!decl_binds_to_current_def_p (decl))
1086 /* On some machines, it is good to increase alignment sometimes. */
1087 #ifdef DATA_ALIGNMENT
1088 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1089 /* Don't increase alignment too much for TLS variables - TLS space
1090 is too precious. */
1091 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1092 align = data_align;
1093 #endif
1094 if (DECL_INITIAL (decl) != 0
1095 /* In LTO we have no errors in program; error_mark_node is used
1096 to mark offlined constructors. */
1097 && (in_lto_p || DECL_INITIAL (decl) != error_mark_node))
1099 unsigned int const_align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl),
1100 align);
1101 /* Don't increase alignment too much for TLS variables - TLS space
1102 is too precious. */
1103 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1104 align = const_align;
1108 return align;
1111 /* Return the section into which the given VAR_DECL or CONST_DECL
1112 should be placed. PREFER_NOSWITCH_P is true if a noswitch
1113 section should be used wherever possible. */
1115 section *
1116 get_variable_section (tree decl, bool prefer_noswitch_p)
1118 addr_space_t as = ADDR_SPACE_GENERIC;
1119 int reloc;
1120 varpool_node *vnode = varpool_node::get (decl);
1121 if (vnode)
1123 vnode = vnode->ultimate_alias_target ();
1124 decl = vnode->decl;
1127 if (TREE_TYPE (decl) != error_mark_node)
1128 as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1130 /* We need the constructor to figure out reloc flag. */
1131 if (vnode)
1132 vnode->get_constructor ();
1134 if (DECL_COMMON (decl))
1136 /* If the decl has been given an explicit section name, or it resides
1137 in a non-generic address space, then it isn't common, and shouldn't
1138 be handled as such. */
1139 gcc_assert (DECL_SECTION_NAME (decl) == NULL
1140 && ADDR_SPACE_GENERIC_P (as));
1141 if (DECL_THREAD_LOCAL_P (decl))
1142 return tls_comm_section;
1143 else if (TREE_PUBLIC (decl) && bss_initializer_p (decl))
1144 return comm_section;
1147 if (DECL_INITIAL (decl) == error_mark_node)
1148 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1149 else if (DECL_INITIAL (decl))
1150 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1151 else
1152 reloc = 0;
1154 resolve_unique_section (decl, reloc, flag_data_sections);
1155 if (IN_NAMED_SECTION (decl))
1157 section *sect = get_named_section (decl, NULL, reloc);
1159 if ((sect->common.flags & SECTION_BSS) && !bss_initializer_p (decl))
1161 error_at (DECL_SOURCE_LOCATION (decl),
1162 "only zero initializers are allowed in section %qs",
1163 sect->named.name);
1164 DECL_INITIAL (decl) = error_mark_node;
1166 return sect;
1169 if (ADDR_SPACE_GENERIC_P (as)
1170 && !DECL_THREAD_LOCAL_P (decl)
1171 && !(prefer_noswitch_p && targetm.have_switchable_bss_sections)
1172 && bss_initializer_p (decl))
1174 if (!TREE_PUBLIC (decl)
1175 && !((flag_sanitize & SANITIZE_ADDRESS)
1176 && asan_protect_global (decl)))
1177 return lcomm_section;
1178 if (bss_noswitch_section)
1179 return bss_noswitch_section;
1182 return targetm.asm_out.select_section (decl, reloc,
1183 get_variable_align (decl));
1186 /* Return the block into which object_block DECL should be placed. */
1188 static struct object_block *
1189 get_block_for_decl (tree decl)
1191 section *sect;
1193 if (VAR_P (decl))
1195 /* The object must be defined in this translation unit. */
1196 if (DECL_EXTERNAL (decl))
1197 return NULL;
1199 /* There's no point using object blocks for something that is
1200 isolated by definition. */
1201 if (DECL_COMDAT_GROUP (decl))
1202 return NULL;
1205 /* We can only calculate block offsets if the decl has a known
1206 constant size. */
1207 if (DECL_SIZE_UNIT (decl) == NULL)
1208 return NULL;
1209 if (!tree_fits_uhwi_p (DECL_SIZE_UNIT (decl)))
1210 return NULL;
1212 /* Find out which section should contain DECL. We cannot put it into
1213 an object block if it requires a standalone definition. */
1214 if (VAR_P (decl))
1215 align_variable (decl, 0);
1216 sect = get_variable_section (decl, true);
1217 if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
1218 return NULL;
1220 return get_block_for_section (sect);
1223 /* Make sure block symbol SYMBOL is in block BLOCK. */
1225 static void
1226 change_symbol_block (rtx symbol, struct object_block *block)
1228 if (block != SYMBOL_REF_BLOCK (symbol))
1230 gcc_assert (SYMBOL_REF_BLOCK_OFFSET (symbol) < 0);
1231 SYMBOL_REF_BLOCK (symbol) = block;
1235 /* Return true if it is possible to put DECL in an object_block. */
1237 static bool
1238 use_blocks_for_decl_p (tree decl)
1240 struct symtab_node *snode;
1242 /* Only data DECLs can be placed into object blocks. */
1243 if (!VAR_P (decl) && TREE_CODE (decl) != CONST_DECL)
1244 return false;
1246 /* Detect decls created by dw2_force_const_mem. Such decls are
1247 special because DECL_INITIAL doesn't specify the decl's true value.
1248 dw2_output_indirect_constants will instead call assemble_variable
1249 with dont_output_data set to 1 and then print the contents itself. */
1250 if (DECL_INITIAL (decl) == decl)
1251 return false;
1253 /* If this decl is an alias, then we don't want to emit a
1254 definition. */
1255 if (VAR_P (decl)
1256 && (snode = symtab_node::get (decl)) != NULL
1257 && snode->alias)
1258 return false;
1260 return targetm.use_blocks_for_decl_p (decl);
1263 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS
1264 until we find an identifier that is not itself a transparent alias.
1265 Modify the alias passed to it by reference (and all aliases on the
1266 way to the ultimate target), such that they do not have to be
1267 followed again, and return the ultimate target of the alias
1268 chain. */
1270 static inline tree
1271 ultimate_transparent_alias_target (tree *alias)
1273 tree target = *alias;
1275 if (IDENTIFIER_TRANSPARENT_ALIAS (target))
1277 gcc_assert (TREE_CHAIN (target));
1278 target = ultimate_transparent_alias_target (&TREE_CHAIN (target));
1279 gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target)
1280 && ! TREE_CHAIN (target));
1281 *alias = target;
1284 return target;
1287 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
1288 have static storage duration. In other words, it should not be an
1289 automatic variable, including PARM_DECLs.
1291 There is, however, one exception: this function handles variables
1292 explicitly placed in a particular register by the user.
1294 This is never called for PARM_DECL nodes. */
1296 void
1297 make_decl_rtl (tree decl)
1299 const char *name = 0;
1300 int reg_number;
1301 tree id;
1302 rtx x;
1304 /* Check that we are not being given an automatic variable. */
1305 gcc_assert (TREE_CODE (decl) != PARM_DECL
1306 && TREE_CODE (decl) != RESULT_DECL);
1308 /* A weak alias has TREE_PUBLIC set but not the other bits. */
1309 gcc_assert (!VAR_P (decl)
1310 || TREE_STATIC (decl)
1311 || TREE_PUBLIC (decl)
1312 || DECL_EXTERNAL (decl)
1313 || DECL_REGISTER (decl));
1315 /* And that we were not given a type or a label. */
1316 gcc_assert (TREE_CODE (decl) != TYPE_DECL
1317 && TREE_CODE (decl) != LABEL_DECL);
1319 /* For a duplicate declaration, we can be called twice on the
1320 same DECL node. Don't discard the RTL already made. */
1321 if (DECL_RTL_SET_P (decl))
1323 /* If the old RTL had the wrong mode, fix the mode. */
1324 x = DECL_RTL (decl);
1325 if (GET_MODE (x) != DECL_MODE (decl))
1326 SET_DECL_RTL (decl, adjust_address_nv (x, DECL_MODE (decl), 0));
1328 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1329 return;
1331 /* ??? Another way to do this would be to maintain a hashed
1332 table of such critters. Instead of adding stuff to a DECL
1333 to give certain attributes to it, we could use an external
1334 hash map from DECL to set of attributes. */
1336 /* Let the target reassign the RTL if it wants.
1337 This is necessary, for example, when one machine specific
1338 decl attribute overrides another. */
1339 targetm.encode_section_info (decl, DECL_RTL (decl), false);
1341 /* If the symbol has a SYMBOL_REF_BLOCK field, update it based
1342 on the new decl information. */
1343 if (MEM_P (x)
1344 && GET_CODE (XEXP (x, 0)) == SYMBOL_REF
1345 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (x, 0)))
1346 change_symbol_block (XEXP (x, 0), get_block_for_decl (decl));
1348 return;
1351 /* If this variable belongs to the global constant pool, retrieve the
1352 pre-computed RTL or recompute it in LTO mode. */
1353 if (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
1355 SET_DECL_RTL (decl, output_constant_def (DECL_INITIAL (decl), 1));
1356 return;
1359 id = DECL_ASSEMBLER_NAME (decl);
1360 if (TREE_CODE (decl) == FUNCTION_DECL
1361 && cgraph_node::get (decl)
1362 && cgraph_node::get (decl)->instrumentation_clone)
1363 ultimate_transparent_alias_target (&id);
1364 name = IDENTIFIER_POINTER (id);
1366 if (name[0] != '*' && TREE_CODE (decl) != FUNCTION_DECL
1367 && DECL_REGISTER (decl))
1369 error ("register name not specified for %q+D", decl);
1371 else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1373 const char *asmspec = name+1;
1374 machine_mode mode = DECL_MODE (decl);
1375 reg_number = decode_reg_name (asmspec);
1376 /* First detect errors in declaring global registers. */
1377 if (reg_number == -1)
1378 error ("register name not specified for %q+D", decl);
1379 else if (reg_number < 0)
1380 error ("invalid register name for %q+D", decl);
1381 else if (mode == BLKmode)
1382 error ("data type of %q+D isn%'t suitable for a register",
1383 decl);
1384 else if (!in_hard_reg_set_p (accessible_reg_set, mode, reg_number))
1385 error ("the register specified for %q+D cannot be accessed"
1386 " by the current target", decl);
1387 else if (!in_hard_reg_set_p (operand_reg_set, mode, reg_number))
1388 error ("the register specified for %q+D is not general enough"
1389 " to be used as a register variable", decl);
1390 else if (!targetm.hard_regno_mode_ok (reg_number, mode))
1391 error ("register specified for %q+D isn%'t suitable for data type",
1392 decl);
1393 /* Now handle properly declared static register variables. */
1394 else
1396 int nregs;
1398 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
1400 DECL_INITIAL (decl) = 0;
1401 error ("global register variable has initial value");
1403 if (TREE_THIS_VOLATILE (decl))
1404 warning (OPT_Wvolatile_register_var,
1405 "optimization may eliminate reads and/or "
1406 "writes to register variables");
1408 /* If the user specified one of the eliminables registers here,
1409 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
1410 confused with that register and be eliminated. This usage is
1411 somewhat suspect... */
1413 SET_DECL_RTL (decl, gen_raw_REG (mode, reg_number));
1414 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
1415 REG_USERVAR_P (DECL_RTL (decl)) = 1;
1417 if (TREE_STATIC (decl))
1419 /* Make this register global, so not usable for anything
1420 else. */
1421 #ifdef ASM_DECLARE_REGISTER_GLOBAL
1422 name = IDENTIFIER_POINTER (DECL_NAME (decl));
1423 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
1424 #endif
1425 nregs = hard_regno_nregs[reg_number][mode];
1426 while (nregs > 0)
1427 globalize_reg (decl, reg_number + --nregs);
1430 /* As a register variable, it has no section. */
1431 return;
1433 /* Avoid internal errors from invalid register
1434 specifications. */
1435 SET_DECL_ASSEMBLER_NAME (decl, NULL_TREE);
1436 DECL_HARD_REGISTER (decl) = 0;
1437 /* Also avoid SSA inconsistencies by pretending this is an external
1438 decl now. */
1439 DECL_EXTERNAL (decl) = 1;
1440 return;
1442 /* Now handle ordinary static variables and functions (in memory).
1443 Also handle vars declared register invalidly. */
1444 else if (name[0] == '*')
1446 #ifdef REGISTER_PREFIX
1447 if (strlen (REGISTER_PREFIX) != 0)
1449 reg_number = decode_reg_name (name);
1450 if (reg_number >= 0 || reg_number == -3)
1451 error ("register name given for non-register variable %q+D", decl);
1453 #endif
1456 /* Specifying a section attribute on a variable forces it into a
1457 non-.bss section, and thus it cannot be common. */
1458 /* FIXME: In general this code should not be necessary because
1459 visibility pass is doing the same work. But notice_global_symbol
1460 is called early and it needs to make DECL_RTL to get the name.
1461 we take care of recomputing the DECL_RTL after visibility is changed. */
1462 if (VAR_P (decl)
1463 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl))
1464 && DECL_SECTION_NAME (decl) != NULL
1465 && DECL_INITIAL (decl) == NULL_TREE
1466 && DECL_COMMON (decl))
1467 DECL_COMMON (decl) = 0;
1469 /* Variables can't be both common and weak. */
1470 if (VAR_P (decl) && DECL_WEAK (decl))
1471 DECL_COMMON (decl) = 0;
1473 if (use_object_blocks_p () && use_blocks_for_decl_p (decl))
1474 x = create_block_symbol (name, get_block_for_decl (decl), -1);
1475 else
1477 machine_mode address_mode = Pmode;
1478 if (TREE_TYPE (decl) != error_mark_node)
1480 addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1481 address_mode = targetm.addr_space.address_mode (as);
1483 x = gen_rtx_SYMBOL_REF (address_mode, name);
1485 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
1486 SET_SYMBOL_REF_DECL (x, decl);
1488 x = gen_rtx_MEM (DECL_MODE (decl), x);
1489 if (TREE_CODE (decl) != FUNCTION_DECL)
1490 set_mem_attributes (x, decl, 1);
1491 SET_DECL_RTL (decl, x);
1493 /* Optionally set flags or add text to the name to record information
1494 such as that it is a function name.
1495 If the name is changed, the macro ASM_OUTPUT_LABELREF
1496 will have to know how to strip this information. */
1497 targetm.encode_section_info (decl, DECL_RTL (decl), true);
1500 /* Like make_decl_rtl, but inhibit creation of new alias sets when
1501 calling make_decl_rtl. Also, reset DECL_RTL before returning the
1502 rtl. */
1505 make_decl_rtl_for_debug (tree decl)
1507 unsigned int save_aliasing_flag;
1508 rtx rtl;
1510 if (DECL_RTL_SET_P (decl))
1511 return DECL_RTL (decl);
1513 /* Kludge alert! Somewhere down the call chain, make_decl_rtl will
1514 call new_alias_set. If running with -fcompare-debug, sometimes
1515 we do not want to create alias sets that will throw the alias
1516 numbers off in the comparison dumps. So... clearing
1517 flag_strict_aliasing will keep new_alias_set() from creating a
1518 new set. */
1519 save_aliasing_flag = flag_strict_aliasing;
1520 flag_strict_aliasing = 0;
1522 rtl = DECL_RTL (decl);
1523 /* Reset DECL_RTL back, as various parts of the compiler expects
1524 DECL_RTL set meaning it is actually going to be output. */
1525 SET_DECL_RTL (decl, NULL);
1527 flag_strict_aliasing = save_aliasing_flag;
1528 return rtl;
1531 /* Output a string of literal assembler code
1532 for an `asm' keyword used between functions. */
1534 void
1535 assemble_asm (tree string)
1537 const char *p;
1538 app_enable ();
1540 if (TREE_CODE (string) == ADDR_EXPR)
1541 string = TREE_OPERAND (string, 0);
1543 p = TREE_STRING_POINTER (string);
1544 fprintf (asm_out_file, "%s%s\n", p[0] == '\t' ? "" : "\t", p);
1547 /* Write the address of the entity given by SYMBOL to SEC. */
1548 void
1549 assemble_addr_to_section (rtx symbol, section *sec)
1551 switch_to_section (sec);
1552 assemble_align (POINTER_SIZE);
1553 assemble_integer (symbol, POINTER_SIZE_UNITS, POINTER_SIZE, 1);
1556 /* Return the numbered .ctors.N (if CONSTRUCTOR_P) or .dtors.N (if
1557 not) section for PRIORITY. */
1558 section *
1559 get_cdtor_priority_section (int priority, bool constructor_p)
1561 /* Buffer conservatively large enough for the full range of a 32-bit
1562 int plus the text below. */
1563 char buf[18];
1565 /* ??? This only works reliably with the GNU linker. */
1566 sprintf (buf, "%s.%.5u",
1567 constructor_p ? ".ctors" : ".dtors",
1568 /* Invert the numbering so the linker puts us in the proper
1569 order; constructors are run from right to left, and the
1570 linker sorts in increasing order. */
1571 MAX_INIT_PRIORITY - priority);
1572 return get_section (buf, SECTION_WRITE, NULL);
1575 void
1576 default_named_section_asm_out_destructor (rtx symbol, int priority)
1578 section *sec;
1580 if (priority != DEFAULT_INIT_PRIORITY)
1581 sec = get_cdtor_priority_section (priority,
1582 /*constructor_p=*/false);
1583 else
1584 sec = get_section (".dtors", SECTION_WRITE, NULL);
1586 assemble_addr_to_section (symbol, sec);
1589 #ifdef DTORS_SECTION_ASM_OP
1590 void
1591 default_dtor_section_asm_out_destructor (rtx symbol,
1592 int priority ATTRIBUTE_UNUSED)
1594 assemble_addr_to_section (symbol, dtors_section);
1596 #endif
1598 void
1599 default_named_section_asm_out_constructor (rtx symbol, int priority)
1601 section *sec;
1603 if (priority != DEFAULT_INIT_PRIORITY)
1604 sec = get_cdtor_priority_section (priority,
1605 /*constructor_p=*/true);
1606 else
1607 sec = get_section (".ctors", SECTION_WRITE, NULL);
1609 assemble_addr_to_section (symbol, sec);
1612 #ifdef CTORS_SECTION_ASM_OP
1613 void
1614 default_ctor_section_asm_out_constructor (rtx symbol,
1615 int priority ATTRIBUTE_UNUSED)
1617 assemble_addr_to_section (symbol, ctors_section);
1619 #endif
1621 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1622 a nonzero value if the constant pool should be output before the
1623 start of the function, or a zero value if the pool should output
1624 after the end of the function. The default is to put it before the
1625 start. */
1627 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1628 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1629 #endif
1631 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1632 to be output to assembler.
1633 Set first_global_object_name and weak_global_object_name as appropriate. */
1635 void
1636 notice_global_symbol (tree decl)
1638 const char **t = &first_global_object_name;
1640 if (first_global_object_name
1641 || !TREE_PUBLIC (decl)
1642 || DECL_EXTERNAL (decl)
1643 || !DECL_NAME (decl)
1644 || (VAR_P (decl) && DECL_HARD_REGISTER (decl))
1645 || (TREE_CODE (decl) != FUNCTION_DECL
1646 && (!VAR_P (decl)
1647 || (DECL_COMMON (decl)
1648 && (DECL_INITIAL (decl) == 0
1649 || DECL_INITIAL (decl) == error_mark_node)))))
1650 return;
1652 /* We win when global object is found, but it is useful to know about weak
1653 symbol as well so we can produce nicer unique names. */
1654 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl) || flag_shlib)
1655 t = &weak_global_object_name;
1657 if (!*t)
1659 tree id = DECL_ASSEMBLER_NAME (decl);
1660 ultimate_transparent_alias_target (&id);
1661 *t = ggc_strdup (targetm.strip_name_encoding (IDENTIFIER_POINTER (id)));
1665 /* If not using flag_reorder_blocks_and_partition, decide early whether the
1666 current function goes into the cold section, so that targets can use
1667 current_function_section during RTL expansion. DECL describes the
1668 function. */
1670 void
1671 decide_function_section (tree decl)
1673 first_function_block_is_cold = false;
1675 if (DECL_SECTION_NAME (decl))
1677 struct cgraph_node *node = cgraph_node::get (current_function_decl);
1678 /* Calls to function_section rely on first_function_block_is_cold
1679 being accurate. */
1680 first_function_block_is_cold = (node
1681 && node->frequency
1682 == NODE_FREQUENCY_UNLIKELY_EXECUTED);
1685 in_cold_section_p = first_function_block_is_cold;
1688 /* Get the function's name, as described by its RTL. This may be
1689 different from the DECL_NAME name used in the source file. */
1690 const char *
1691 get_fnname_from_decl (tree decl)
1693 rtx x = DECL_RTL (decl);
1694 gcc_assert (MEM_P (x));
1695 x = XEXP (x, 0);
1696 gcc_assert (GET_CODE (x) == SYMBOL_REF);
1697 return XSTR (x, 0);
1700 /* Output assembler code for the constant pool of a function and associated
1701 with defining the name of the function. DECL describes the function.
1702 NAME is the function's name. For the constant pool, we use the current
1703 constant pool data. */
1705 void
1706 assemble_start_function (tree decl, const char *fnname)
1708 int align;
1709 char tmp_label[100];
1710 bool hot_label_written = false;
1712 if (crtl->has_bb_partition)
1714 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTB", const_labelno);
1715 crtl->subsections.hot_section_label = ggc_strdup (tmp_label);
1716 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDB", const_labelno);
1717 crtl->subsections.cold_section_label = ggc_strdup (tmp_label);
1718 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTE", const_labelno);
1719 crtl->subsections.hot_section_end_label = ggc_strdup (tmp_label);
1720 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDE", const_labelno);
1721 crtl->subsections.cold_section_end_label = ggc_strdup (tmp_label);
1722 const_labelno++;
1723 cold_function_name = NULL_TREE;
1725 else
1727 crtl->subsections.hot_section_label = NULL;
1728 crtl->subsections.cold_section_label = NULL;
1729 crtl->subsections.hot_section_end_label = NULL;
1730 crtl->subsections.cold_section_end_label = NULL;
1733 /* The following code does not need preprocessing in the assembler. */
1735 app_disable ();
1737 if (CONSTANT_POOL_BEFORE_FUNCTION)
1738 output_constant_pool (fnname, decl);
1740 align = symtab_node::get (decl)->definition_alignment ();
1742 /* Make sure the not and cold text (code) sections are properly
1743 aligned. This is necessary here in the case where the function
1744 has both hot and cold sections, because we don't want to re-set
1745 the alignment when the section switch happens mid-function. */
1747 if (crtl->has_bb_partition)
1749 first_function_block_is_cold = false;
1751 switch_to_section (unlikely_text_section ());
1752 assemble_align (align);
1753 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_label);
1755 /* When the function starts with a cold section, we need to explicitly
1756 align the hot section and write out the hot section label.
1757 But if the current function is a thunk, we do not have a CFG. */
1758 if (!cfun->is_thunk
1759 && BB_PARTITION (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) == BB_COLD_PARTITION)
1761 switch_to_section (text_section);
1762 assemble_align (align);
1763 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1764 hot_label_written = true;
1765 first_function_block_is_cold = true;
1767 in_cold_section_p = first_function_block_is_cold;
1771 /* Switch to the correct text section for the start of the function. */
1773 switch_to_section (function_section (decl));
1774 if (crtl->has_bb_partition && !hot_label_written)
1775 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1777 /* Tell assembler to move to target machine's alignment for functions. */
1778 align = floor_log2 (align / BITS_PER_UNIT);
1779 if (align > 0)
1781 ASM_OUTPUT_ALIGN (asm_out_file, align);
1784 /* Handle a user-specified function alignment.
1785 Note that we still need to align to DECL_ALIGN, as above,
1786 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1787 if (! DECL_USER_ALIGN (decl)
1788 && align_functions_log > align
1789 && optimize_function_for_speed_p (cfun))
1791 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1792 int align_log = align_functions_log;
1793 #endif
1794 int max_skip = align_functions - 1;
1795 if (flag_limit_function_alignment && crtl->max_insn_address > 0
1796 && max_skip >= crtl->max_insn_address)
1797 max_skip = crtl->max_insn_address - 1;
1799 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1800 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file, align_log, max_skip);
1801 #else
1802 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1803 #endif
1806 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1807 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1808 #endif
1810 if (!DECL_IGNORED_P (decl))
1811 (*debug_hooks->begin_function) (decl);
1813 /* Make function name accessible from other files, if appropriate. */
1815 if (TREE_PUBLIC (decl)
1816 || (cgraph_node::get (decl)->instrumentation_clone
1817 && cgraph_node::get (decl)->instrumented_version
1818 && TREE_PUBLIC (cgraph_node::get (decl)->instrumented_version->decl)))
1820 notice_global_symbol (decl);
1822 globalize_decl (decl);
1824 maybe_assemble_visibility (decl);
1827 if (DECL_PRESERVE_P (decl))
1828 targetm.asm_out.mark_decl_preserved (fnname);
1830 unsigned HOST_WIDE_INT patch_area_size = function_entry_patch_area_size;
1831 unsigned HOST_WIDE_INT patch_area_entry = function_entry_patch_area_start;
1833 tree patchable_function_entry_attr
1834 = lookup_attribute ("patchable_function_entry", DECL_ATTRIBUTES (decl));
1835 if (patchable_function_entry_attr)
1837 tree pp_val = TREE_VALUE (patchable_function_entry_attr);
1838 tree patchable_function_entry_value1 = TREE_VALUE (pp_val);
1840 if (tree_fits_uhwi_p (patchable_function_entry_value1))
1841 patch_area_size = tree_to_uhwi (patchable_function_entry_value1);
1842 else
1843 gcc_unreachable ();
1845 patch_area_entry = 0;
1846 if (list_length (pp_val) > 1)
1848 tree patchable_function_entry_value2 =
1849 TREE_VALUE (TREE_CHAIN (pp_val));
1851 if (tree_fits_uhwi_p (patchable_function_entry_value2))
1852 patch_area_entry = tree_to_uhwi (patchable_function_entry_value2);
1853 else
1854 gcc_unreachable ();
1858 if (patch_area_entry > patch_area_size)
1860 if (patch_area_size > 0)
1861 warning (OPT_Wattributes, "Patchable function entry > size");
1862 patch_area_entry = 0;
1865 /* Emit the patching area before the entry label, if any. */
1866 if (patch_area_entry > 0)
1867 targetm.asm_out.print_patchable_function_entry (asm_out_file,
1868 patch_area_entry, true);
1870 /* Do any machine/system dependent processing of the function name. */
1871 #ifdef ASM_DECLARE_FUNCTION_NAME
1872 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1873 #else
1874 /* Standard thing is just output label for the function. */
1875 ASM_OUTPUT_FUNCTION_LABEL (asm_out_file, fnname, current_function_decl);
1876 #endif /* ASM_DECLARE_FUNCTION_NAME */
1878 /* And the area after the label. Record it if we haven't done so yet. */
1879 if (patch_area_size > patch_area_entry)
1880 targetm.asm_out.print_patchable_function_entry (asm_out_file,
1881 patch_area_size-patch_area_entry,
1882 patch_area_entry == 0);
1884 if (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (decl)))
1885 saw_no_split_stack = true;
1888 /* Output assembler code associated with defining the size of the
1889 function. DECL describes the function. NAME is the function's name. */
1891 void
1892 assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED)
1894 #ifdef ASM_DECLARE_FUNCTION_SIZE
1895 /* We could have switched section in the middle of the function. */
1896 if (crtl->has_bb_partition)
1897 switch_to_section (function_section (decl));
1898 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1899 #endif
1900 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1902 output_constant_pool (fnname, decl);
1903 switch_to_section (function_section (decl)); /* need to switch back */
1905 /* Output labels for end of hot/cold text sections (to be used by
1906 debug info.) */
1907 if (crtl->has_bb_partition)
1909 section *save_text_section;
1911 save_text_section = in_section;
1912 switch_to_section (unlikely_text_section ());
1913 #ifdef ASM_DECLARE_COLD_FUNCTION_SIZE
1914 if (cold_function_name != NULL_TREE)
1915 ASM_DECLARE_COLD_FUNCTION_SIZE (asm_out_file,
1916 IDENTIFIER_POINTER (cold_function_name),
1917 decl);
1918 #endif
1919 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label);
1920 if (first_function_block_is_cold)
1921 switch_to_section (text_section);
1922 else
1923 switch_to_section (function_section (decl));
1924 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label);
1925 switch_to_section (save_text_section);
1929 /* Assemble code to leave SIZE bytes of zeros. */
1931 void
1932 assemble_zeros (unsigned HOST_WIDE_INT size)
1934 /* Do no output if -fsyntax-only. */
1935 if (flag_syntax_only)
1936 return;
1938 #ifdef ASM_NO_SKIP_IN_TEXT
1939 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1940 so we must output 0s explicitly in the text section. */
1941 if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0)
1943 unsigned HOST_WIDE_INT i;
1944 for (i = 0; i < size; i++)
1945 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1947 else
1948 #endif
1949 if (size > 0)
1950 ASM_OUTPUT_SKIP (asm_out_file, size);
1953 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1955 void
1956 assemble_align (int align)
1958 if (align > BITS_PER_UNIT)
1960 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1964 /* Assemble a string constant with the specified C string as contents. */
1966 void
1967 assemble_string (const char *p, int size)
1969 int pos = 0;
1970 int maximum = 2000;
1972 /* If the string is very long, split it up. */
1974 while (pos < size)
1976 int thissize = size - pos;
1977 if (thissize > maximum)
1978 thissize = maximum;
1980 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1982 pos += thissize;
1983 p += thissize;
1988 /* A noswitch_section_callback for lcomm_section. */
1990 static bool
1991 emit_local (tree decl ATTRIBUTE_UNUSED,
1992 const char *name ATTRIBUTE_UNUSED,
1993 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1994 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1996 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1997 unsigned int align = symtab_node::get (decl)->definition_alignment ();
1998 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name,
1999 size, align);
2000 return true;
2001 #elif defined ASM_OUTPUT_ALIGNED_LOCAL
2002 unsigned int align = symtab_node::get (decl)->definition_alignment ();
2003 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, align);
2004 return true;
2005 #else
2006 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2007 return false;
2008 #endif
2011 /* A noswitch_section_callback for bss_noswitch_section. */
2013 #if defined ASM_OUTPUT_ALIGNED_BSS
2014 static bool
2015 emit_bss (tree decl ATTRIBUTE_UNUSED,
2016 const char *name ATTRIBUTE_UNUSED,
2017 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2018 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2020 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size,
2021 get_variable_align (decl));
2022 return true;
2024 #endif
2026 /* A noswitch_section_callback for comm_section. */
2028 static bool
2029 emit_common (tree decl ATTRIBUTE_UNUSED,
2030 const char *name ATTRIBUTE_UNUSED,
2031 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2032 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2034 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
2035 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name,
2036 size, get_variable_align (decl));
2037 return true;
2038 #elif defined ASM_OUTPUT_ALIGNED_COMMON
2039 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size,
2040 get_variable_align (decl));
2041 return true;
2042 #else
2043 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
2044 return false;
2045 #endif
2048 /* A noswitch_section_callback for tls_comm_section. */
2050 static bool
2051 emit_tls_common (tree decl ATTRIBUTE_UNUSED,
2052 const char *name ATTRIBUTE_UNUSED,
2053 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2054 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2056 #ifdef ASM_OUTPUT_TLS_COMMON
2057 ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size);
2058 return true;
2059 #else
2060 sorry ("thread-local COMMON data not implemented");
2061 return true;
2062 #endif
2065 /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT.
2066 NAME is the name of DECL's SYMBOL_REF. */
2068 static void
2069 assemble_noswitch_variable (tree decl, const char *name, section *sect,
2070 unsigned int align)
2072 unsigned HOST_WIDE_INT size, rounded;
2074 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2075 rounded = size;
2077 if ((flag_sanitize & SANITIZE_ADDRESS) && asan_protect_global (decl))
2078 size += asan_red_zone_size (size);
2080 /* Don't allocate zero bytes of common,
2081 since that means "undefined external" in the linker. */
2082 if (size == 0)
2083 rounded = 1;
2085 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2086 so that each uninitialized object starts on such a boundary. */
2087 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
2088 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2089 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2091 if (!sect->noswitch.callback (decl, name, size, rounded)
2092 && (unsigned HOST_WIDE_INT) (align / BITS_PER_UNIT) > rounded)
2093 error ("requested alignment for %q+D is greater than "
2094 "implemented alignment of %wu", decl, rounded);
2097 /* A subroutine of assemble_variable. Output the label and contents of
2098 DECL, whose address is a SYMBOL_REF with name NAME. DONT_OUTPUT_DATA
2099 is as for assemble_variable. */
2101 static void
2102 assemble_variable_contents (tree decl, const char *name,
2103 bool dont_output_data)
2105 /* Do any machine/system dependent processing of the object. */
2106 #ifdef ASM_DECLARE_OBJECT_NAME
2107 last_assemble_variable_decl = decl;
2108 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
2109 #else
2110 /* Standard thing is just output label for the object. */
2111 ASM_OUTPUT_LABEL (asm_out_file, name);
2112 #endif /* ASM_DECLARE_OBJECT_NAME */
2114 if (!dont_output_data)
2116 /* Caller is supposed to use varpool_get_constructor when it wants
2117 to output the body. */
2118 gcc_assert (!in_lto_p || DECL_INITIAL (decl) != error_mark_node);
2119 if (DECL_INITIAL (decl)
2120 && DECL_INITIAL (decl) != error_mark_node
2121 && !initializer_zerop (DECL_INITIAL (decl)))
2122 /* Output the actual data. */
2123 output_constant (DECL_INITIAL (decl),
2124 tree_to_uhwi (DECL_SIZE_UNIT (decl)),
2125 get_variable_align (decl),
2126 false);
2127 else
2128 /* Leave space for it. */
2129 assemble_zeros (tree_to_uhwi (DECL_SIZE_UNIT (decl)));
2130 targetm.asm_out.decl_end ();
2134 /* Write out assembly for the variable DECL, which is not defined in
2135 the current translation unit. */
2136 void
2137 assemble_undefined_decl (tree decl)
2139 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
2140 targetm.asm_out.assemble_undefined_decl (asm_out_file, name, decl);
2143 /* Assemble everything that is needed for a variable or function declaration.
2144 Not used for automatic variables, and not used for function definitions.
2145 Should not be called for variables of incomplete structure type.
2147 TOP_LEVEL is nonzero if this variable has file scope.
2148 AT_END is nonzero if this is the special handling, at end of compilation,
2149 to define things that have had only tentative definitions.
2150 DONT_OUTPUT_DATA if nonzero means don't actually output the
2151 initial value (that will be done by the caller). */
2153 void
2154 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
2155 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
2157 const char *name;
2158 rtx decl_rtl, symbol;
2159 section *sect;
2160 unsigned int align;
2161 bool asan_protected = false;
2163 /* This function is supposed to handle VARIABLES. Ensure we have one. */
2164 gcc_assert (VAR_P (decl));
2166 /* Emulated TLS had better not get this far. */
2167 gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl));
2169 last_assemble_variable_decl = 0;
2171 /* Normally no need to say anything here for external references,
2172 since assemble_external is called by the language-specific code
2173 when a declaration is first seen. */
2175 if (DECL_EXTERNAL (decl))
2176 return;
2178 /* Do nothing for global register variables. */
2179 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
2181 TREE_ASM_WRITTEN (decl) = 1;
2182 return;
2185 /* If type was incomplete when the variable was declared,
2186 see if it is complete now. */
2188 if (DECL_SIZE (decl) == 0)
2189 layout_decl (decl, 0);
2191 /* Still incomplete => don't allocate it; treat the tentative defn
2192 (which is what it must have been) as an `extern' reference. */
2194 if (!dont_output_data && DECL_SIZE (decl) == 0)
2196 error ("storage size of %q+D isn%'t known", decl);
2197 TREE_ASM_WRITTEN (decl) = 1;
2198 return;
2201 /* The first declaration of a variable that comes through this function
2202 decides whether it is global (in C, has external linkage)
2203 or local (in C, has internal linkage). So do nothing more
2204 if this function has already run. */
2206 if (TREE_ASM_WRITTEN (decl))
2207 return;
2209 /* Make sure targetm.encode_section_info is invoked before we set
2210 ASM_WRITTEN. */
2211 decl_rtl = DECL_RTL (decl);
2213 TREE_ASM_WRITTEN (decl) = 1;
2215 /* Do no output if -fsyntax-only. */
2216 if (flag_syntax_only)
2217 return;
2219 if (! dont_output_data
2220 && ! valid_constant_size_p (DECL_SIZE_UNIT (decl)))
2222 error ("size of variable %q+D is too large", decl);
2223 return;
2226 gcc_assert (MEM_P (decl_rtl));
2227 gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF);
2228 symbol = XEXP (decl_rtl, 0);
2230 /* If this symbol belongs to the tree constant pool, output the constant
2231 if it hasn't already been written. */
2232 if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
2234 tree decl = SYMBOL_REF_DECL (symbol);
2235 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
2236 output_constant_def_contents (symbol);
2237 return;
2240 app_disable ();
2242 name = XSTR (symbol, 0);
2243 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
2244 notice_global_symbol (decl);
2246 /* Compute the alignment of this data. */
2248 align_variable (decl, dont_output_data);
2250 if ((flag_sanitize & SANITIZE_ADDRESS)
2251 && asan_protect_global (decl))
2253 asan_protected = true;
2254 SET_DECL_ALIGN (decl, MAX (DECL_ALIGN (decl),
2255 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT));
2258 set_mem_align (decl_rtl, DECL_ALIGN (decl));
2260 align = get_variable_align (decl);
2262 if (TREE_PUBLIC (decl))
2263 maybe_assemble_visibility (decl);
2265 if (DECL_PRESERVE_P (decl))
2266 targetm.asm_out.mark_decl_preserved (name);
2268 /* First make the assembler name(s) global if appropriate. */
2269 sect = get_variable_section (decl, false);
2270 if (TREE_PUBLIC (decl)
2271 && (sect->common.flags & SECTION_COMMON) == 0)
2272 globalize_decl (decl);
2274 /* Output any data that we will need to use the address of. */
2275 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
2276 output_addressed_constants (DECL_INITIAL (decl));
2278 /* dbxout.c needs to know this. */
2279 if (sect && (sect->common.flags & SECTION_CODE) != 0)
2280 DECL_IN_TEXT_SECTION (decl) = 1;
2282 /* If the decl is part of an object_block, make sure that the decl
2283 has been positioned within its block, but do not write out its
2284 definition yet. output_object_blocks will do that later. */
2285 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
2287 gcc_assert (!dont_output_data);
2288 place_block_symbol (symbol);
2290 else if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
2291 assemble_noswitch_variable (decl, name, sect, align);
2292 else
2294 /* Special-case handling of vtv comdat sections. */
2295 if (sect->named.name
2296 && (strcmp (sect->named.name, ".vtable_map_vars") == 0))
2297 handle_vtv_comdat_section (sect, decl);
2298 else
2299 switch_to_section (sect);
2300 if (align > BITS_PER_UNIT)
2301 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2302 assemble_variable_contents (decl, name, dont_output_data);
2303 if (asan_protected)
2305 unsigned HOST_WIDE_INT int size
2306 = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2307 assemble_zeros (asan_red_zone_size (size));
2313 /* Given a function declaration (FN_DECL), this function assembles the
2314 function into the .preinit_array section. */
2316 void
2317 assemble_vtv_preinit_initializer (tree fn_decl)
2319 section *sect;
2320 unsigned flags = SECTION_WRITE;
2321 rtx symbol = XEXP (DECL_RTL (fn_decl), 0);
2323 flags |= SECTION_NOTYPE;
2324 sect = get_section (".preinit_array", flags, fn_decl);
2325 switch_to_section (sect);
2326 assemble_addr_to_section (symbol, sect);
2329 /* Return 1 if type TYPE contains any pointers. */
2331 static int
2332 contains_pointers_p (tree type)
2334 switch (TREE_CODE (type))
2336 case POINTER_TYPE:
2337 case REFERENCE_TYPE:
2338 /* I'm not sure whether OFFSET_TYPE needs this treatment,
2339 so I'll play safe and return 1. */
2340 case OFFSET_TYPE:
2341 return 1;
2343 case RECORD_TYPE:
2344 case UNION_TYPE:
2345 case QUAL_UNION_TYPE:
2347 tree fields;
2348 /* For a type that has fields, see if the fields have pointers. */
2349 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2350 if (TREE_CODE (fields) == FIELD_DECL
2351 && contains_pointers_p (TREE_TYPE (fields)))
2352 return 1;
2353 return 0;
2356 case ARRAY_TYPE:
2357 /* An array type contains pointers if its element type does. */
2358 return contains_pointers_p (TREE_TYPE (type));
2360 default:
2361 return 0;
2365 /* We delay assemble_external processing until
2366 the compilation unit is finalized. This is the best we can do for
2367 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2368 it all the way to final. See PR 17982 for further discussion. */
2369 static GTY(()) tree pending_assemble_externals;
2371 #ifdef ASM_OUTPUT_EXTERNAL
2372 /* Some targets delay some output to final using TARGET_ASM_FILE_END.
2373 As a result, assemble_external can be called after the list of externals
2374 is processed and the pointer set destroyed. */
2375 static bool pending_assemble_externals_processed;
2377 /* Avoid O(external_decls**2) lookups in the pending_assemble_externals
2378 TREE_LIST in assemble_external. */
2379 static hash_set<tree> *pending_assemble_externals_set;
2381 /* True if DECL is a function decl for which no out-of-line copy exists.
2382 It is assumed that DECL's assembler name has been set. */
2384 static bool
2385 incorporeal_function_p (tree decl)
2387 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
2389 const char *name;
2391 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2392 && (DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA
2393 || DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA_WITH_ALIGN))
2394 return true;
2396 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2397 /* Atomic or sync builtins which have survived this far will be
2398 resolved externally and therefore are not incorporeal. */
2399 if (strncmp (name, "__builtin_", 10) == 0)
2400 return true;
2402 return false;
2405 /* Actually do the tests to determine if this is necessary, and invoke
2406 ASM_OUTPUT_EXTERNAL. */
2407 static void
2408 assemble_external_real (tree decl)
2410 rtx rtl = DECL_RTL (decl);
2412 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2413 && !SYMBOL_REF_USED (XEXP (rtl, 0))
2414 && !incorporeal_function_p (decl))
2416 /* Some systems do require some output. */
2417 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2418 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2421 #endif
2423 void
2424 process_pending_assemble_externals (void)
2426 #ifdef ASM_OUTPUT_EXTERNAL
2427 tree list;
2428 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2429 assemble_external_real (TREE_VALUE (list));
2431 pending_assemble_externals = 0;
2432 pending_assemble_externals_processed = true;
2433 delete pending_assemble_externals_set;
2434 #endif
2437 /* This TREE_LIST contains any weak symbol declarations waiting
2438 to be emitted. */
2439 static GTY(()) tree weak_decls;
2441 /* Output something to declare an external symbol to the assembler,
2442 and qualifiers such as weakness. (Most assemblers don't need
2443 extern declaration, so we normally output nothing.) Do nothing if
2444 DECL is not external. */
2446 void
2447 assemble_external (tree decl ATTRIBUTE_UNUSED)
2449 /* Make sure that the ASM_OUT_FILE is open.
2450 If it's not, we should not be calling this function. */
2451 gcc_assert (asm_out_file);
2453 /* In a perfect world, the following condition would be true.
2454 Sadly, the Go front end emit assembly *from the front end*,
2455 bypassing the call graph. See PR52739. Fix before GCC 4.8. */
2456 #if 0
2457 /* This function should only be called if we are expanding, or have
2458 expanded, to RTL.
2459 Ideally, only final.c would be calling this function, but it is
2460 not clear whether that would break things somehow. See PR 17982
2461 for further discussion. */
2462 gcc_assert (state == EXPANSION
2463 || state == FINISHED);
2464 #endif
2466 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2467 return;
2469 /* We want to output annotation for weak and external symbols at
2470 very last to check if they are references or not. */
2472 if (TARGET_SUPPORTS_WEAK
2473 && DECL_WEAK (decl)
2474 /* TREE_STATIC is a weird and abused creature which is not
2475 generally the right test for whether an entity has been
2476 locally emitted, inlined or otherwise not-really-extern, but
2477 for declarations that can be weak, it happens to be
2478 match. */
2479 && !TREE_STATIC (decl)
2480 && lookup_attribute ("weak", DECL_ATTRIBUTES (decl))
2481 && value_member (decl, weak_decls) == NULL_TREE)
2482 weak_decls = tree_cons (NULL, decl, weak_decls);
2484 #ifdef ASM_OUTPUT_EXTERNAL
2485 if (pending_assemble_externals_processed)
2487 assemble_external_real (decl);
2488 return;
2491 if (! pending_assemble_externals_set->add (decl))
2492 pending_assemble_externals = tree_cons (NULL, decl,
2493 pending_assemble_externals);
2494 #endif
2497 /* Similar, for calling a library function FUN. */
2499 void
2500 assemble_external_libcall (rtx fun)
2502 /* Declare library function name external when first used, if nec. */
2503 if (! SYMBOL_REF_USED (fun))
2505 SYMBOL_REF_USED (fun) = 1;
2506 targetm.asm_out.external_libcall (fun);
2510 /* Assemble a label named NAME. */
2512 void
2513 assemble_label (FILE *file, const char *name)
2515 ASM_OUTPUT_LABEL (file, name);
2518 /* Set the symbol_referenced flag for ID. */
2519 void
2520 mark_referenced (tree id)
2522 TREE_SYMBOL_REFERENCED (id) = 1;
2525 /* Set the symbol_referenced flag for DECL and notify callgraph. */
2526 void
2527 mark_decl_referenced (tree decl)
2529 if (TREE_CODE (decl) == FUNCTION_DECL)
2531 /* Extern inline functions don't become needed when referenced.
2532 If we know a method will be emitted in other TU and no new
2533 functions can be marked reachable, just use the external
2534 definition. */
2535 struct cgraph_node *node = cgraph_node::get_create (decl);
2536 if (!DECL_EXTERNAL (decl)
2537 && !node->definition)
2538 node->mark_force_output ();
2540 else if (VAR_P (decl))
2542 varpool_node *node = varpool_node::get_create (decl);
2543 /* C++ frontend use mark_decl_references to force COMDAT variables
2544 to be output that might appear dead otherwise. */
2545 node->force_output = true;
2547 /* else do nothing - we can get various sorts of CST nodes here,
2548 which do not need to be marked. */
2552 /* Output to FILE (an assembly file) a reference to NAME. If NAME
2553 starts with a *, the rest of NAME is output verbatim. Otherwise
2554 NAME is transformed in a target-specific way (usually by the
2555 addition of an underscore). */
2557 void
2558 assemble_name_raw (FILE *file, const char *name)
2560 if (name[0] == '*')
2561 fputs (&name[1], file);
2562 else
2563 ASM_OUTPUT_LABELREF (file, name);
2566 /* Like assemble_name_raw, but should be used when NAME might refer to
2567 an entity that is also represented as a tree (like a function or
2568 variable). If NAME does refer to such an entity, that entity will
2569 be marked as referenced. */
2571 void
2572 assemble_name (FILE *file, const char *name)
2574 const char *real_name;
2575 tree id;
2577 real_name = targetm.strip_name_encoding (name);
2579 id = maybe_get_identifier (real_name);
2580 if (id)
2582 tree id_orig = id;
2584 mark_referenced (id);
2585 ultimate_transparent_alias_target (&id);
2586 if (id != id_orig)
2587 name = IDENTIFIER_POINTER (id);
2588 gcc_assert (! TREE_CHAIN (id));
2591 assemble_name_raw (file, name);
2594 /* Allocate SIZE bytes writable static space with a gensym name
2595 and return an RTX to refer to its address. */
2598 assemble_static_space (unsigned HOST_WIDE_INT size)
2600 char name[17];
2601 const char *namestring;
2602 rtx x;
2604 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2605 ++const_labelno;
2606 namestring = ggc_strdup (name);
2608 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2609 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2611 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2612 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2613 BIGGEST_ALIGNMENT);
2614 #else
2615 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2616 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2617 #else
2619 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2620 so that each uninitialized object starts on such a boundary. */
2621 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2622 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2623 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2624 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2625 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2626 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2628 #endif
2629 #endif
2630 return x;
2633 /* Assemble the static constant template for function entry trampolines.
2634 This is done at most once per compilation.
2635 Returns an RTX for the address of the template. */
2637 static GTY(()) rtx initial_trampoline;
2640 assemble_trampoline_template (void)
2642 char label[256];
2643 const char *name;
2644 int align;
2645 rtx symbol;
2647 gcc_assert (targetm.asm_out.trampoline_template != NULL);
2649 if (initial_trampoline)
2650 return initial_trampoline;
2652 /* By default, put trampoline templates in read-only data section. */
2654 #ifdef TRAMPOLINE_SECTION
2655 switch_to_section (TRAMPOLINE_SECTION);
2656 #else
2657 switch_to_section (readonly_data_section);
2658 #endif
2660 /* Write the assembler code to define one. */
2661 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2662 if (align > 0)
2663 ASM_OUTPUT_ALIGN (asm_out_file, align);
2665 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2666 targetm.asm_out.trampoline_template (asm_out_file);
2668 /* Record the rtl to refer to it. */
2669 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2670 name = ggc_strdup (label);
2671 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2672 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2674 initial_trampoline = gen_const_mem (BLKmode, symbol);
2675 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2676 set_mem_size (initial_trampoline, TRAMPOLINE_SIZE);
2678 return initial_trampoline;
2681 /* A and B are either alignments or offsets. Return the minimum alignment
2682 that may be assumed after adding the two together. */
2684 static inline unsigned
2685 min_align (unsigned int a, unsigned int b)
2687 return least_bit_hwi (a | b);
2690 /* Return the assembler directive for creating a given kind of integer
2691 object. SIZE is the number of bytes in the object and ALIGNED_P
2692 indicates whether it is known to be aligned. Return NULL if the
2693 assembly dialect has no such directive.
2695 The returned string should be printed at the start of a new line and
2696 be followed immediately by the object's initial value. */
2698 const char *
2699 integer_asm_op (int size, int aligned_p)
2701 struct asm_int_op *ops;
2703 if (aligned_p)
2704 ops = &targetm.asm_out.aligned_op;
2705 else
2706 ops = &targetm.asm_out.unaligned_op;
2708 switch (size)
2710 case 1:
2711 return targetm.asm_out.byte_op;
2712 case 2:
2713 return ops->hi;
2714 case 4:
2715 return ops->si;
2716 case 8:
2717 return ops->di;
2718 case 16:
2719 return ops->ti;
2720 default:
2721 return NULL;
2725 /* Use directive OP to assemble an integer object X. Print OP at the
2726 start of the line, followed immediately by the value of X. */
2728 void
2729 assemble_integer_with_op (const char *op, rtx x)
2731 fputs (op, asm_out_file);
2732 output_addr_const (asm_out_file, x);
2733 fputc ('\n', asm_out_file);
2736 /* The default implementation of the asm_out.integer target hook. */
2738 bool
2739 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2740 unsigned int size ATTRIBUTE_UNUSED,
2741 int aligned_p ATTRIBUTE_UNUSED)
2743 const char *op = integer_asm_op (size, aligned_p);
2744 /* Avoid GAS bugs for large values. Specifically negative values whose
2745 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2746 if (size > UNITS_PER_WORD && size > POINTER_SIZE_UNITS)
2747 return false;
2748 return op && (assemble_integer_with_op (op, x), true);
2751 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2752 the alignment of the integer in bits. Return 1 if we were able to output
2753 the constant, otherwise 0. We must be able to output the constant,
2754 if FORCE is nonzero. */
2756 bool
2757 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2759 int aligned_p;
2761 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2763 /* See if the target hook can handle this kind of object. */
2764 if (targetm.asm_out.integer (x, size, aligned_p))
2765 return true;
2767 /* If the object is a multi-byte one, try splitting it up. Split
2768 it into words it if is multi-word, otherwise split it into bytes. */
2769 if (size > 1)
2771 machine_mode omode, imode;
2772 unsigned int subalign;
2773 unsigned int subsize, i;
2774 enum mode_class mclass;
2776 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2777 subalign = MIN (align, subsize * BITS_PER_UNIT);
2778 if (GET_CODE (x) == CONST_FIXED)
2779 mclass = GET_MODE_CLASS (GET_MODE (x));
2780 else
2781 mclass = MODE_INT;
2783 omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0).require ();
2784 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0).require ();
2786 for (i = 0; i < size; i += subsize)
2788 rtx partial = simplify_subreg (omode, x, imode, i);
2789 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2790 break;
2792 if (i == size)
2793 return true;
2795 /* If we've printed some of it, but not all of it, there's no going
2796 back now. */
2797 gcc_assert (!i);
2800 gcc_assert (!force);
2802 return false;
2805 /* Assemble the floating-point constant D into an object of size MODE. ALIGN
2806 is the alignment of the constant in bits. If REVERSE is true, D is output
2807 in reverse storage order. */
2809 void
2810 assemble_real (REAL_VALUE_TYPE d, scalar_float_mode mode, unsigned int align,
2811 bool reverse)
2813 long data[4] = {0, 0, 0, 0};
2814 int bitsize, nelts, nunits, units_per;
2815 rtx elt;
2817 /* This is hairy. We have a quantity of known size. real_to_target
2818 will put it into an array of *host* longs, 32 bits per element
2819 (even if long is more than 32 bits). We need to determine the
2820 number of array elements that are occupied (nelts) and the number
2821 of *target* min-addressable units that will be occupied in the
2822 object file (nunits). We cannot assume that 32 divides the
2823 mode's bitsize (size * BITS_PER_UNIT) evenly.
2825 size * BITS_PER_UNIT is used here to make sure that padding bits
2826 (which might appear at either end of the value; real_to_target
2827 will include the padding bits in its output array) are included. */
2829 nunits = GET_MODE_SIZE (mode);
2830 bitsize = nunits * BITS_PER_UNIT;
2831 nelts = CEIL (bitsize, 32);
2832 units_per = 32 / BITS_PER_UNIT;
2834 real_to_target (data, &d, mode);
2836 /* Put out the first word with the specified alignment. */
2837 if (reverse)
2838 elt = flip_storage_order (SImode, gen_int_mode (data[nelts - 1], SImode));
2839 else
2840 elt = GEN_INT (data[0]);
2841 assemble_integer (elt, MIN (nunits, units_per), align, 1);
2842 nunits -= units_per;
2844 /* Subsequent words need only 32-bit alignment. */
2845 align = min_align (align, 32);
2847 for (int i = 1; i < nelts; i++)
2849 if (reverse)
2850 elt = flip_storage_order (SImode,
2851 gen_int_mode (data[nelts - 1 - i], SImode));
2852 else
2853 elt = GEN_INT (data[i]);
2854 assemble_integer (elt, MIN (nunits, units_per), align, 1);
2855 nunits -= units_per;
2859 /* Given an expression EXP with a constant value,
2860 reduce it to the sum of an assembler symbol and an integer.
2861 Store them both in the structure *VALUE.
2862 EXP must be reducible. */
2864 struct addr_const {
2865 rtx base;
2866 HOST_WIDE_INT offset;
2869 static void
2870 decode_addr_const (tree exp, struct addr_const *value)
2872 tree target = TREE_OPERAND (exp, 0);
2873 int offset = 0;
2874 rtx x;
2876 while (1)
2878 if (TREE_CODE (target) == COMPONENT_REF
2879 && tree_fits_shwi_p (byte_position (TREE_OPERAND (target, 1))))
2881 offset += int_byte_position (TREE_OPERAND (target, 1));
2882 target = TREE_OPERAND (target, 0);
2884 else if (TREE_CODE (target) == ARRAY_REF
2885 || TREE_CODE (target) == ARRAY_RANGE_REF)
2887 offset += (tree_to_uhwi (TYPE_SIZE_UNIT (TREE_TYPE (target)))
2888 * tree_to_shwi (TREE_OPERAND (target, 1)));
2889 target = TREE_OPERAND (target, 0);
2891 else if (TREE_CODE (target) == MEM_REF
2892 && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR)
2894 offset += mem_ref_offset (target).to_short_addr ();
2895 target = TREE_OPERAND (TREE_OPERAND (target, 0), 0);
2897 else if (TREE_CODE (target) == INDIRECT_REF
2898 && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR
2899 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0))
2900 == ADDR_EXPR)
2901 target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0);
2902 else
2903 break;
2906 switch (TREE_CODE (target))
2908 case VAR_DECL:
2909 case FUNCTION_DECL:
2910 x = DECL_RTL (target);
2911 break;
2913 case LABEL_DECL:
2914 x = gen_rtx_MEM (FUNCTION_MODE,
2915 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2916 break;
2918 case REAL_CST:
2919 case FIXED_CST:
2920 case STRING_CST:
2921 case COMPLEX_CST:
2922 case CONSTRUCTOR:
2923 case INTEGER_CST:
2924 x = output_constant_def (target, 1);
2925 break;
2927 case INDIRECT_REF:
2928 /* This deals with absolute addresses. */
2929 offset += tree_to_shwi (TREE_OPERAND (target, 0));
2930 x = gen_rtx_MEM (QImode,
2931 gen_rtx_SYMBOL_REF (Pmode, "origin of addresses"));
2932 break;
2934 default:
2935 gcc_unreachable ();
2938 gcc_assert (MEM_P (x));
2939 x = XEXP (x, 0);
2941 value->base = x;
2942 value->offset = offset;
2945 static GTY(()) hash_table<tree_descriptor_hasher> *const_desc_htab;
2947 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2949 /* Constant pool accessor function. */
2951 hash_table<tree_descriptor_hasher> *
2952 constant_pool_htab (void)
2954 return const_desc_htab;
2957 /* Compute a hash code for a constant expression. */
2959 hashval_t
2960 tree_descriptor_hasher::hash (constant_descriptor_tree *ptr)
2962 return ptr->hash;
2965 static hashval_t
2966 const_hash_1 (const tree exp)
2968 const char *p;
2969 hashval_t hi;
2970 int len, i;
2971 enum tree_code code = TREE_CODE (exp);
2973 /* Either set P and LEN to the address and len of something to hash and
2974 exit the switch or return a value. */
2976 switch (code)
2978 case INTEGER_CST:
2979 p = (char *) &TREE_INT_CST_ELT (exp, 0);
2980 len = TREE_INT_CST_NUNITS (exp) * sizeof (HOST_WIDE_INT);
2981 break;
2983 case REAL_CST:
2984 return real_hash (TREE_REAL_CST_PTR (exp));
2986 case FIXED_CST:
2987 return fixed_hash (TREE_FIXED_CST_PTR (exp));
2989 case STRING_CST:
2990 p = TREE_STRING_POINTER (exp);
2991 len = TREE_STRING_LENGTH (exp);
2992 break;
2994 case COMPLEX_CST:
2995 return (const_hash_1 (TREE_REALPART (exp)) * 5
2996 + const_hash_1 (TREE_IMAGPART (exp)));
2998 case VECTOR_CST:
3000 unsigned i;
3002 hi = 7 + VECTOR_CST_NELTS (exp);
3004 for (i = 0; i < VECTOR_CST_NELTS (exp); ++i)
3005 hi = hi * 563 + const_hash_1 (VECTOR_CST_ELT (exp, i));
3007 return hi;
3010 case CONSTRUCTOR:
3012 unsigned HOST_WIDE_INT idx;
3013 tree value;
3015 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
3017 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
3018 if (value)
3019 hi = hi * 603 + const_hash_1 (value);
3021 return hi;
3024 case ADDR_EXPR:
3025 case FDESC_EXPR:
3027 struct addr_const value;
3029 decode_addr_const (exp, &value);
3030 switch (GET_CODE (value.base))
3032 case SYMBOL_REF:
3033 /* Don't hash the address of the SYMBOL_REF;
3034 only use the offset and the symbol name. */
3035 hi = value.offset;
3036 p = XSTR (value.base, 0);
3037 for (i = 0; p[i] != 0; i++)
3038 hi = ((hi * 613) + (unsigned) (p[i]));
3039 break;
3041 case LABEL_REF:
3042 hi = (value.offset
3043 + CODE_LABEL_NUMBER (label_ref_label (value.base)) * 13);
3044 break;
3046 default:
3047 gcc_unreachable ();
3050 return hi;
3052 case PLUS_EXPR:
3053 case POINTER_PLUS_EXPR:
3054 case MINUS_EXPR:
3055 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
3056 + const_hash_1 (TREE_OPERAND (exp, 1)));
3058 CASE_CONVERT:
3059 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
3061 default:
3062 /* A language specific constant. Just hash the code. */
3063 return code;
3066 /* Compute hashing function. */
3067 hi = len;
3068 for (i = 0; i < len; i++)
3069 hi = ((hi * 613) + (unsigned) (p[i]));
3071 return hi;
3074 /* Wrapper of compare_constant, for the htab interface. */
3075 bool
3076 tree_descriptor_hasher::equal (constant_descriptor_tree *c1,
3077 constant_descriptor_tree *c2)
3079 if (c1->hash != c2->hash)
3080 return 0;
3081 return compare_constant (c1->value, c2->value);
3084 /* Compare t1 and t2, and return 1 only if they are known to result in
3085 the same bit pattern on output. */
3087 static int
3088 compare_constant (const tree t1, const tree t2)
3090 enum tree_code typecode;
3092 if (t1 == NULL_TREE)
3093 return t2 == NULL_TREE;
3094 if (t2 == NULL_TREE)
3095 return 0;
3097 if (TREE_CODE (t1) != TREE_CODE (t2))
3098 return 0;
3100 switch (TREE_CODE (t1))
3102 case INTEGER_CST:
3103 /* Integer constants are the same only if the same width of type. */
3104 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3105 return 0;
3106 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3107 return 0;
3108 return tree_int_cst_equal (t1, t2);
3110 case REAL_CST:
3111 /* Real constants are the same only if the same width of type. */
3112 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3113 return 0;
3115 return real_identical (&TREE_REAL_CST (t1), &TREE_REAL_CST (t2));
3117 case FIXED_CST:
3118 /* Fixed constants are the same only if the same width of type. */
3119 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3120 return 0;
3122 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
3124 case STRING_CST:
3125 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3126 return 0;
3128 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
3129 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
3130 TREE_STRING_LENGTH (t1)));
3132 case COMPLEX_CST:
3133 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
3134 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
3136 case VECTOR_CST:
3138 unsigned i;
3140 if (VECTOR_CST_NELTS (t1) != VECTOR_CST_NELTS (t2))
3141 return 0;
3143 for (i = 0; i < VECTOR_CST_NELTS (t1); ++i)
3144 if (!compare_constant (VECTOR_CST_ELT (t1, i),
3145 VECTOR_CST_ELT (t2, i)))
3146 return 0;
3148 return 1;
3151 case CONSTRUCTOR:
3153 vec<constructor_elt, va_gc> *v1, *v2;
3154 unsigned HOST_WIDE_INT idx;
3156 typecode = TREE_CODE (TREE_TYPE (t1));
3157 if (typecode != TREE_CODE (TREE_TYPE (t2)))
3158 return 0;
3160 if (typecode == ARRAY_TYPE)
3162 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
3163 /* For arrays, check that mode, size and storage order match. */
3164 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
3165 || size_1 == -1
3166 || size_1 != int_size_in_bytes (TREE_TYPE (t2))
3167 || TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (t1))
3168 != TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (t2)))
3169 return 0;
3171 else
3173 /* For record and union constructors, require exact type
3174 equality. */
3175 if (TREE_TYPE (t1) != TREE_TYPE (t2))
3176 return 0;
3179 v1 = CONSTRUCTOR_ELTS (t1);
3180 v2 = CONSTRUCTOR_ELTS (t2);
3181 if (vec_safe_length (v1) != vec_safe_length (v2))
3182 return 0;
3184 for (idx = 0; idx < vec_safe_length (v1); ++idx)
3186 constructor_elt *c1 = &(*v1)[idx];
3187 constructor_elt *c2 = &(*v2)[idx];
3189 /* Check that each value is the same... */
3190 if (!compare_constant (c1->value, c2->value))
3191 return 0;
3192 /* ... and that they apply to the same fields! */
3193 if (typecode == ARRAY_TYPE)
3195 if (!compare_constant (c1->index, c2->index))
3196 return 0;
3198 else
3200 if (c1->index != c2->index)
3201 return 0;
3205 return 1;
3208 case ADDR_EXPR:
3209 case FDESC_EXPR:
3211 struct addr_const value1, value2;
3212 enum rtx_code code;
3213 int ret;
3215 decode_addr_const (t1, &value1);
3216 decode_addr_const (t2, &value2);
3218 if (value1.offset != value2.offset)
3219 return 0;
3221 code = GET_CODE (value1.base);
3222 if (code != GET_CODE (value2.base))
3223 return 0;
3225 switch (code)
3227 case SYMBOL_REF:
3228 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3229 break;
3231 case LABEL_REF:
3232 ret = (CODE_LABEL_NUMBER (label_ref_label (value1.base))
3233 == CODE_LABEL_NUMBER (label_ref_label (value2.base)));
3234 break;
3236 default:
3237 gcc_unreachable ();
3239 return ret;
3242 case PLUS_EXPR:
3243 case POINTER_PLUS_EXPR:
3244 case MINUS_EXPR:
3245 case RANGE_EXPR:
3246 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3247 && compare_constant (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3249 CASE_CONVERT:
3250 case VIEW_CONVERT_EXPR:
3251 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3253 default:
3254 return 0;
3257 gcc_unreachable ();
3260 /* Return the section into which constant EXP should be placed. */
3262 static section *
3263 get_constant_section (tree exp, unsigned int align)
3265 return targetm.asm_out.select_section (exp,
3266 compute_reloc_for_constant (exp),
3267 align);
3270 /* Return the size of constant EXP in bytes. */
3272 static HOST_WIDE_INT
3273 get_constant_size (tree exp)
3275 HOST_WIDE_INT size;
3277 size = int_size_in_bytes (TREE_TYPE (exp));
3278 if (TREE_CODE (exp) == STRING_CST)
3279 size = MAX (TREE_STRING_LENGTH (exp), size);
3280 return size;
3283 /* Subroutine of output_constant_def:
3284 No constant equal to EXP is known to have been output.
3285 Make a constant descriptor to enter EXP in the hash table.
3286 Assign the label number and construct RTL to refer to the
3287 constant's location in memory.
3288 Caller is responsible for updating the hash table. */
3290 static struct constant_descriptor_tree *
3291 build_constant_desc (tree exp)
3293 struct constant_descriptor_tree *desc;
3294 rtx symbol, rtl;
3295 char label[256];
3296 int labelno;
3297 tree decl;
3299 desc = ggc_alloc<constant_descriptor_tree> ();
3300 desc->value = exp;
3302 /* Create a string containing the label name, in LABEL. */
3303 labelno = const_labelno++;
3304 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3306 /* Construct the VAR_DECL associated with the constant. */
3307 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3308 TREE_TYPE (exp));
3309 DECL_ARTIFICIAL (decl) = 1;
3310 DECL_IGNORED_P (decl) = 1;
3311 TREE_READONLY (decl) = 1;
3312 TREE_STATIC (decl) = 1;
3313 TREE_ADDRESSABLE (decl) = 1;
3314 /* We don't set the RTL yet as this would cause varpool to assume that the
3315 variable is referenced. Moreover, it would just be dropped in LTO mode.
3316 Instead we set the flag that will be recognized in make_decl_rtl. */
3317 DECL_IN_CONSTANT_POOL (decl) = 1;
3318 DECL_INITIAL (decl) = desc->value;
3319 /* ??? CONSTANT_ALIGNMENT hasn't been updated for vector types on most
3320 architectures so use DATA_ALIGNMENT as well, except for strings. */
3321 if (TREE_CODE (exp) == STRING_CST)
3323 SET_DECL_ALIGN (decl, CONSTANT_ALIGNMENT (exp, DECL_ALIGN (decl)));
3325 else
3326 align_variable (decl, 0);
3328 /* Now construct the SYMBOL_REF and the MEM. */
3329 if (use_object_blocks_p ())
3331 int align = (TREE_CODE (decl) == CONST_DECL
3332 || (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
3333 ? DECL_ALIGN (decl)
3334 : symtab_node::get (decl)->definition_alignment ());
3335 section *sect = get_constant_section (exp, align);
3336 symbol = create_block_symbol (ggc_strdup (label),
3337 get_block_for_section (sect), -1);
3339 else
3340 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3341 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3342 SET_SYMBOL_REF_DECL (symbol, decl);
3343 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3345 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3346 set_mem_attributes (rtl, exp, 1);
3347 set_mem_alias_set (rtl, 0);
3349 /* Putting EXP into the literal pool might have imposed a different
3350 alignment which should be visible in the RTX as well. */
3351 set_mem_align (rtl, DECL_ALIGN (decl));
3353 /* We cannot share RTX'es in pool entries.
3354 Mark this piece of RTL as required for unsharing. */
3355 RTX_FLAG (rtl, used) = 1;
3357 /* Set flags or add text to the name to record information, such as
3358 that it is a local symbol. If the name is changed, the macro
3359 ASM_OUTPUT_LABELREF will have to know how to strip this
3360 information. This call might invalidate our local variable
3361 SYMBOL; we can't use it afterward. */
3362 targetm.encode_section_info (exp, rtl, true);
3364 desc->rtl = rtl;
3366 return desc;
3369 /* Return an rtx representing a reference to constant data in memory
3370 for the constant expression EXP.
3372 If assembler code for such a constant has already been output,
3373 return an rtx to refer to it.
3374 Otherwise, output such a constant in memory
3375 and generate an rtx for it.
3377 If DEFER is nonzero, this constant can be deferred and output only
3378 if referenced in the function after all optimizations.
3380 `const_desc_table' records which constants already have label strings. */
3383 output_constant_def (tree exp, int defer)
3385 struct constant_descriptor_tree *desc;
3386 struct constant_descriptor_tree key;
3388 /* Look up EXP in the table of constant descriptors. If we didn't find
3389 it, create a new one. */
3390 key.value = exp;
3391 key.hash = const_hash_1 (exp);
3392 constant_descriptor_tree **loc
3393 = const_desc_htab->find_slot_with_hash (&key, key.hash, INSERT);
3395 desc = *loc;
3396 if (desc == 0)
3398 desc = build_constant_desc (exp);
3399 desc->hash = key.hash;
3400 *loc = desc;
3403 maybe_output_constant_def_contents (desc, defer);
3404 return desc->rtl;
3407 /* Subroutine of output_constant_def: Decide whether or not we need to
3408 output the constant DESC now, and if so, do it. */
3409 static void
3410 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3411 int defer)
3413 rtx symbol = XEXP (desc->rtl, 0);
3414 tree exp = desc->value;
3416 if (flag_syntax_only)
3417 return;
3419 if (TREE_ASM_WRITTEN (exp))
3420 /* Already output; don't do it again. */
3421 return;
3423 /* We can always defer constants as long as the context allows
3424 doing so. */
3425 if (defer)
3427 /* Increment n_deferred_constants if it exists. It needs to be at
3428 least as large as the number of constants actually referred to
3429 by the function. If it's too small we'll stop looking too early
3430 and fail to emit constants; if it's too large we'll only look
3431 through the entire function when we could have stopped earlier. */
3432 if (cfun)
3433 n_deferred_constants++;
3434 return;
3437 output_constant_def_contents (symbol);
3440 /* Subroutine of output_constant_def_contents. Output the definition
3441 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3442 constant's alignment in bits. */
3444 static void
3445 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3447 HOST_WIDE_INT size;
3449 size = get_constant_size (exp);
3451 /* Do any machine/system dependent processing of the constant. */
3452 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3454 /* Output the value of EXP. */
3455 output_constant (exp, size, align, false);
3457 targetm.asm_out.decl_end ();
3460 /* We must output the constant data referred to by SYMBOL; do so. */
3462 static void
3463 output_constant_def_contents (rtx symbol)
3465 tree decl = SYMBOL_REF_DECL (symbol);
3466 tree exp = DECL_INITIAL (decl);
3467 bool asan_protected = false;
3469 /* Make sure any other constants whose addresses appear in EXP
3470 are assigned label numbers. */
3471 output_addressed_constants (exp);
3473 /* We are no longer deferring this constant. */
3474 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3476 if ((flag_sanitize & SANITIZE_ADDRESS)
3477 && TREE_CODE (exp) == STRING_CST
3478 && asan_protect_global (exp))
3480 asan_protected = true;
3481 SET_DECL_ALIGN (decl, MAX (DECL_ALIGN (decl),
3482 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT));
3485 /* If the constant is part of an object block, make sure that the
3486 decl has been positioned within its block, but do not write out
3487 its definition yet. output_object_blocks will do that later. */
3488 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3489 place_block_symbol (symbol);
3490 else
3492 int align = (TREE_CODE (decl) == CONST_DECL
3493 || (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
3494 ? DECL_ALIGN (decl)
3495 : symtab_node::get (decl)->definition_alignment ());
3496 switch_to_section (get_constant_section (exp, align));
3497 if (align > BITS_PER_UNIT)
3498 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3499 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3500 if (asan_protected)
3502 HOST_WIDE_INT size = get_constant_size (exp);
3503 assemble_zeros (asan_red_zone_size (size));
3508 /* Look up EXP in the table of constant descriptors. Return the rtl
3509 if it has been emitted, else null. */
3512 lookup_constant_def (tree exp)
3514 struct constant_descriptor_tree key;
3516 key.value = exp;
3517 key.hash = const_hash_1 (exp);
3518 constant_descriptor_tree *desc
3519 = const_desc_htab->find_with_hash (&key, key.hash);
3521 return (desc ? desc->rtl : NULL_RTX);
3524 /* Return a tree representing a reference to constant data in memory
3525 for the constant expression EXP.
3527 This is the counterpart of output_constant_def at the Tree level. */
3529 tree
3530 tree_output_constant_def (tree exp)
3532 struct constant_descriptor_tree *desc, key;
3533 tree decl;
3535 /* Look up EXP in the table of constant descriptors. If we didn't find
3536 it, create a new one. */
3537 key.value = exp;
3538 key.hash = const_hash_1 (exp);
3539 constant_descriptor_tree **loc
3540 = const_desc_htab->find_slot_with_hash (&key, key.hash, INSERT);
3542 desc = *loc;
3543 if (desc == 0)
3545 desc = build_constant_desc (exp);
3546 desc->hash = key.hash;
3547 *loc = desc;
3550 decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3551 varpool_node::finalize_decl (decl);
3552 return decl;
3555 struct GTY((chain_next ("%h.next"), for_user)) constant_descriptor_rtx {
3556 struct constant_descriptor_rtx *next;
3557 rtx mem;
3558 rtx sym;
3559 rtx constant;
3560 HOST_WIDE_INT offset;
3561 hashval_t hash;
3562 machine_mode mode;
3563 unsigned int align;
3564 int labelno;
3565 int mark;
3568 struct const_rtx_desc_hasher : ggc_ptr_hash<constant_descriptor_rtx>
3570 static hashval_t hash (constant_descriptor_rtx *);
3571 static bool equal (constant_descriptor_rtx *, constant_descriptor_rtx *);
3574 /* Used in the hash tables to avoid outputting the same constant
3575 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3576 are output once per function, not once per file. */
3577 /* ??? Only a few targets need per-function constant pools. Most
3578 can use one per-file pool. Should add a targetm bit to tell the
3579 difference. */
3581 struct GTY(()) rtx_constant_pool {
3582 /* Pointers to first and last constant in pool, as ordered by offset. */
3583 struct constant_descriptor_rtx *first;
3584 struct constant_descriptor_rtx *last;
3586 /* Hash facility for making memory-constants from constant rtl-expressions.
3587 It is used on RISC machines where immediate integer arguments and
3588 constant addresses are restricted so that such constants must be stored
3589 in memory. */
3590 hash_table<const_rtx_desc_hasher> *const_rtx_htab;
3592 /* Current offset in constant pool (does not include any
3593 machine-specific header). */
3594 HOST_WIDE_INT offset;
3597 /* Hash and compare functions for const_rtx_htab. */
3599 hashval_t
3600 const_rtx_desc_hasher::hash (constant_descriptor_rtx *desc)
3602 return desc->hash;
3605 bool
3606 const_rtx_desc_hasher::equal (constant_descriptor_rtx *x,
3607 constant_descriptor_rtx *y)
3609 if (x->mode != y->mode)
3610 return 0;
3611 return rtx_equal_p (x->constant, y->constant);
3614 /* Hash one component of a constant. */
3616 static hashval_t
3617 const_rtx_hash_1 (const_rtx x)
3619 unsigned HOST_WIDE_INT hwi;
3620 machine_mode mode;
3621 enum rtx_code code;
3622 hashval_t h;
3623 int i;
3625 code = GET_CODE (x);
3626 mode = GET_MODE (x);
3627 h = (hashval_t) code * 1048573 + mode;
3629 switch (code)
3631 case CONST_INT:
3632 hwi = INTVAL (x);
3634 fold_hwi:
3636 int shift = sizeof (hashval_t) * CHAR_BIT;
3637 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3639 h ^= (hashval_t) hwi;
3640 for (i = 1; i < n; ++i)
3642 hwi >>= shift;
3643 h ^= (hashval_t) hwi;
3646 break;
3648 case CONST_WIDE_INT:
3649 hwi = 0;
3651 for (i = 0; i < CONST_WIDE_INT_NUNITS (x); i++)
3652 hwi ^= CONST_WIDE_INT_ELT (x, i);
3653 goto fold_hwi;
3656 case CONST_DOUBLE:
3657 if (TARGET_SUPPORTS_WIDE_INT == 0 && mode == VOIDmode)
3659 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3660 goto fold_hwi;
3662 else
3663 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3664 break;
3666 case CONST_FIXED:
3667 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3668 break;
3670 case SYMBOL_REF:
3671 h ^= htab_hash_string (XSTR (x, 0));
3672 break;
3674 case LABEL_REF:
3675 h = h * 251 + CODE_LABEL_NUMBER (label_ref_label (x));
3676 break;
3678 case UNSPEC:
3679 case UNSPEC_VOLATILE:
3680 h = h * 251 + XINT (x, 1);
3681 break;
3683 default:
3684 break;
3687 return h;
3690 /* Compute a hash value for X, which should be a constant. */
3692 static hashval_t
3693 const_rtx_hash (rtx x)
3695 hashval_t h = 0;
3696 subrtx_iterator::array_type array;
3697 FOR_EACH_SUBRTX (iter, array, x, ALL)
3698 h = h * 509 + const_rtx_hash_1 (*iter);
3699 return h;
3703 /* Create and return a new rtx constant pool. */
3705 static struct rtx_constant_pool *
3706 create_constant_pool (void)
3708 struct rtx_constant_pool *pool;
3710 pool = ggc_alloc<rtx_constant_pool> ();
3711 pool->const_rtx_htab = hash_table<const_rtx_desc_hasher>::create_ggc (31);
3712 pool->first = NULL;
3713 pool->last = NULL;
3714 pool->offset = 0;
3715 return pool;
3718 /* Initialize constant pool hashing for a new function. */
3720 void
3721 init_varasm_status (void)
3723 crtl->varasm.pool = create_constant_pool ();
3724 crtl->varasm.deferred_constants = 0;
3727 /* Given a MINUS expression, simplify it if both sides
3728 include the same symbol. */
3731 simplify_subtraction (rtx x)
3733 rtx r = simplify_rtx (x);
3734 return r ? r : x;
3737 /* Given a constant rtx X, make (or find) a memory constant for its value
3738 and return a MEM rtx to refer to it in memory. */
3741 force_const_mem (machine_mode mode, rtx x)
3743 struct constant_descriptor_rtx *desc, tmp;
3744 struct rtx_constant_pool *pool;
3745 char label[256];
3746 rtx def, symbol;
3747 hashval_t hash;
3748 unsigned int align;
3749 constant_descriptor_rtx **slot;
3751 /* If we're not allowed to drop X into the constant pool, don't. */
3752 if (targetm.cannot_force_const_mem (mode, x))
3753 return NULL_RTX;
3755 /* Record that this function has used a constant pool entry. */
3756 crtl->uses_const_pool = 1;
3758 /* Decide which pool to use. */
3759 pool = (targetm.use_blocks_for_constant_p (mode, x)
3760 ? shared_constant_pool
3761 : crtl->varasm.pool);
3763 /* Lookup the value in the hashtable. */
3764 tmp.constant = x;
3765 tmp.mode = mode;
3766 hash = const_rtx_hash (x);
3767 slot = pool->const_rtx_htab->find_slot_with_hash (&tmp, hash, INSERT);
3768 desc = *slot;
3770 /* If the constant was already present, return its memory. */
3771 if (desc)
3772 return copy_rtx (desc->mem);
3774 /* Otherwise, create a new descriptor. */
3775 desc = ggc_alloc<constant_descriptor_rtx> ();
3776 *slot = desc;
3778 /* Align the location counter as required by EXP's data type. */
3779 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3781 tree type = lang_hooks.types.type_for_mode (mode, 0);
3782 if (type != NULL_TREE)
3783 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3785 pool->offset += (align / BITS_PER_UNIT) - 1;
3786 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3788 desc->next = NULL;
3789 desc->constant = copy_rtx (tmp.constant);
3790 desc->offset = pool->offset;
3791 desc->hash = hash;
3792 desc->mode = mode;
3793 desc->align = align;
3794 desc->labelno = const_labelno;
3795 desc->mark = 0;
3797 pool->offset += GET_MODE_SIZE (mode);
3798 if (pool->last)
3799 pool->last->next = desc;
3800 else
3801 pool->first = pool->last = desc;
3802 pool->last = desc;
3804 /* Create a string containing the label name, in LABEL. */
3805 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3806 ++const_labelno;
3808 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3809 the constants pool. */
3810 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3812 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3813 symbol = create_block_symbol (ggc_strdup (label),
3814 get_block_for_section (sect), -1);
3816 else
3817 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3818 desc->sym = symbol;
3819 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3820 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3821 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3823 /* Construct the MEM. */
3824 desc->mem = def = gen_const_mem (mode, symbol);
3825 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3826 set_mem_align (def, align);
3828 /* If we're dropping a label to the constant pool, make sure we
3829 don't delete it. */
3830 if (GET_CODE (x) == LABEL_REF)
3831 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3833 return copy_rtx (def);
3836 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3839 get_pool_constant (const_rtx addr)
3841 return SYMBOL_REF_CONSTANT (addr)->constant;
3844 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3845 and whether it has been output or not. */
3848 get_pool_constant_mark (rtx addr, bool *pmarked)
3850 struct constant_descriptor_rtx *desc;
3852 desc = SYMBOL_REF_CONSTANT (addr);
3853 *pmarked = (desc->mark != 0);
3854 return desc->constant;
3857 /* Similar, return the mode. */
3859 machine_mode
3860 get_pool_mode (const_rtx addr)
3862 return SYMBOL_REF_CONSTANT (addr)->mode;
3865 /* Return TRUE if and only if the constant pool has no entries. Note
3866 that even entries we might end up choosing not to emit are counted
3867 here, so there is the potential for missed optimizations. */
3869 bool
3870 constant_pool_empty_p (void)
3872 return crtl->varasm.pool->first == NULL;
3875 /* Worker function for output_constant_pool_1. Emit assembly for X
3876 in MODE with known alignment ALIGN. */
3878 static void
3879 output_constant_pool_2 (machine_mode mode, rtx x, unsigned int align)
3881 switch (GET_MODE_CLASS (mode))
3883 case MODE_FLOAT:
3884 case MODE_DECIMAL_FLOAT:
3886 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3887 assemble_real (*CONST_DOUBLE_REAL_VALUE (x),
3888 as_a <scalar_float_mode> (mode), align, false);
3889 break;
3892 case MODE_INT:
3893 case MODE_PARTIAL_INT:
3894 case MODE_FRACT:
3895 case MODE_UFRACT:
3896 case MODE_ACCUM:
3897 case MODE_UACCUM:
3898 case MODE_POINTER_BOUNDS:
3899 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3900 break;
3902 case MODE_VECTOR_FLOAT:
3903 case MODE_VECTOR_INT:
3904 case MODE_VECTOR_FRACT:
3905 case MODE_VECTOR_UFRACT:
3906 case MODE_VECTOR_ACCUM:
3907 case MODE_VECTOR_UACCUM:
3909 int i, units;
3910 scalar_mode submode = GET_MODE_INNER (mode);
3911 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3913 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3914 units = CONST_VECTOR_NUNITS (x);
3916 for (i = 0; i < units; i++)
3918 rtx elt = CONST_VECTOR_ELT (x, i);
3919 output_constant_pool_2 (submode, elt, i ? subalign : align);
3922 break;
3924 default:
3925 gcc_unreachable ();
3929 /* Worker function for output_constant_pool. Emit constant DESC,
3930 giving it ALIGN bits of alignment. */
3932 static void
3933 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3934 unsigned int align)
3936 rtx x, tmp;
3938 x = desc->constant;
3940 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3941 whose CODE_LABEL has been deleted. This can occur if a jump table
3942 is eliminated by optimization. If so, write a constant of zero
3943 instead. Note that this can also happen by turning the
3944 CODE_LABEL into a NOTE. */
3945 /* ??? This seems completely and utterly wrong. Certainly it's
3946 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3947 functioning even with rtx_insn::deleted and friends. */
3949 tmp = x;
3950 switch (GET_CODE (tmp))
3952 case CONST:
3953 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3954 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
3955 break;
3956 tmp = XEXP (XEXP (tmp, 0), 0);
3957 /* FALLTHRU */
3959 case LABEL_REF:
3961 rtx_insn *insn = label_ref_label (tmp);
3962 gcc_assert (!insn->deleted ());
3963 gcc_assert (!NOTE_P (insn)
3964 || NOTE_KIND (insn) != NOTE_INSN_DELETED);
3965 break;
3968 default:
3969 break;
3972 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3973 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3974 align, desc->labelno, done);
3975 #endif
3977 assemble_align (align);
3979 /* Output the label. */
3980 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3982 /* Output the data.
3983 Pass actual alignment value while emitting string constant to asm code
3984 as function 'output_constant_pool_1' explicitly passes the alignment as 1
3985 assuming that the data is already aligned which prevents the generation
3986 of fix-up table entries. */
3987 output_constant_pool_2 (desc->mode, x, desc->align);
3989 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3990 sections have proper size. */
3991 if (align > GET_MODE_BITSIZE (desc->mode)
3992 && in_section
3993 && (in_section->common.flags & SECTION_MERGE))
3994 assemble_align (align);
3996 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3997 done:
3998 #endif
3999 return;
4002 /* Recompute the offsets of entries in POOL, and the overall size of
4003 POOL. Do this after calling mark_constant_pool to ensure that we
4004 are computing the offset values for the pool which we will actually
4005 emit. */
4007 static void
4008 recompute_pool_offsets (struct rtx_constant_pool *pool)
4010 struct constant_descriptor_rtx *desc;
4011 pool->offset = 0;
4013 for (desc = pool->first; desc ; desc = desc->next)
4014 if (desc->mark)
4016 /* Recalculate offset. */
4017 unsigned int align = desc->align;
4018 pool->offset += (align / BITS_PER_UNIT) - 1;
4019 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
4020 desc->offset = pool->offset;
4021 pool->offset += GET_MODE_SIZE (desc->mode);
4025 /* Mark all constants that are referenced by SYMBOL_REFs in X.
4026 Emit referenced deferred strings. */
4028 static void
4029 mark_constants_in_pattern (rtx insn)
4031 subrtx_iterator::array_type array;
4032 FOR_EACH_SUBRTX (iter, array, PATTERN (insn), ALL)
4034 const_rtx x = *iter;
4035 if (GET_CODE (x) == SYMBOL_REF)
4037 if (CONSTANT_POOL_ADDRESS_P (x))
4039 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
4040 if (desc->mark == 0)
4042 desc->mark = 1;
4043 iter.substitute (desc->constant);
4046 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
4048 tree decl = SYMBOL_REF_DECL (x);
4049 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
4051 n_deferred_constants--;
4052 output_constant_def_contents (CONST_CAST_RTX (x));
4059 /* Look through appropriate parts of INSN, marking all entries in the
4060 constant pool which are actually being used. Entries that are only
4061 referenced by other constants are also marked as used. Emit
4062 deferred strings that are used. */
4064 static void
4065 mark_constants (rtx_insn *insn)
4067 if (!INSN_P (insn))
4068 return;
4070 /* Insns may appear inside a SEQUENCE. Only check the patterns of
4071 insns, not any notes that may be attached. We don't want to mark
4072 a constant just because it happens to appear in a REG_EQUIV note. */
4073 if (rtx_sequence *seq = dyn_cast <rtx_sequence *> (PATTERN (insn)))
4075 int i, n = seq->len ();
4076 for (i = 0; i < n; ++i)
4078 rtx subinsn = seq->element (i);
4079 if (INSN_P (subinsn))
4080 mark_constants_in_pattern (subinsn);
4083 else
4084 mark_constants_in_pattern (insn);
4087 /* Look through the instructions for this function, and mark all the
4088 entries in POOL which are actually being used. Emit deferred constants
4089 which have indeed been used. */
4091 static void
4092 mark_constant_pool (void)
4094 rtx_insn *insn;
4096 if (!crtl->uses_const_pool && n_deferred_constants == 0)
4097 return;
4099 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4100 mark_constants (insn);
4103 /* Write all the constants in POOL. */
4105 static void
4106 output_constant_pool_contents (struct rtx_constant_pool *pool)
4108 struct constant_descriptor_rtx *desc;
4110 for (desc = pool->first; desc ; desc = desc->next)
4111 if (desc->mark)
4113 /* If the constant is part of an object_block, make sure that
4114 the constant has been positioned within its block, but do not
4115 write out its definition yet. output_object_blocks will do
4116 that later. */
4117 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
4118 && SYMBOL_REF_BLOCK (desc->sym))
4119 place_block_symbol (desc->sym);
4120 else
4122 switch_to_section (targetm.asm_out.select_rtx_section
4123 (desc->mode, desc->constant, desc->align));
4124 output_constant_pool_1 (desc, desc->align);
4129 /* Mark all constants that are used in the current function, then write
4130 out the function's private constant pool. */
4132 static void
4133 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
4134 tree fndecl ATTRIBUTE_UNUSED)
4136 struct rtx_constant_pool *pool = crtl->varasm.pool;
4138 /* It is possible for gcc to call force_const_mem and then to later
4139 discard the instructions which refer to the constant. In such a
4140 case we do not need to output the constant. */
4141 mark_constant_pool ();
4143 /* Having marked the constant pool entries we'll actually emit, we
4144 now need to rebuild the offset information, which may have become
4145 stale. */
4146 recompute_pool_offsets (pool);
4148 #ifdef ASM_OUTPUT_POOL_PROLOGUE
4149 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
4150 #endif
4152 output_constant_pool_contents (pool);
4154 #ifdef ASM_OUTPUT_POOL_EPILOGUE
4155 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
4156 #endif
4159 /* Write the contents of the shared constant pool. */
4161 void
4162 output_shared_constant_pool (void)
4164 output_constant_pool_contents (shared_constant_pool);
4167 /* Determine what kind of relocations EXP may need. */
4170 compute_reloc_for_constant (tree exp)
4172 int reloc = 0, reloc2;
4173 tree tem;
4175 switch (TREE_CODE (exp))
4177 case ADDR_EXPR:
4178 case FDESC_EXPR:
4179 /* Go inside any operations that get_inner_reference can handle and see
4180 if what's inside is a constant: no need to do anything here for
4181 addresses of variables or functions. */
4182 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4183 tem = TREE_OPERAND (tem, 0))
4186 if (TREE_CODE (tem) == MEM_REF
4187 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4189 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4190 break;
4193 if (!targetm.binds_local_p (tem))
4194 reloc |= 2;
4195 else
4196 reloc |= 1;
4197 break;
4199 case PLUS_EXPR:
4200 case POINTER_PLUS_EXPR:
4201 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4202 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4203 break;
4205 case MINUS_EXPR:
4206 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4207 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4208 /* The difference of two local labels is computable at link time. */
4209 if (reloc == 1 && reloc2 == 1)
4210 reloc = 0;
4211 else
4212 reloc |= reloc2;
4213 break;
4215 CASE_CONVERT:
4216 case VIEW_CONVERT_EXPR:
4217 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4218 break;
4220 case CONSTRUCTOR:
4222 unsigned HOST_WIDE_INT idx;
4223 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4224 if (tem != 0)
4225 reloc |= compute_reloc_for_constant (tem);
4227 break;
4229 default:
4230 break;
4232 return reloc;
4235 /* Find all the constants whose addresses are referenced inside of EXP,
4236 and make sure assembler code with a label has been output for each one.
4237 Indicate whether an ADDR_EXPR has been encountered. */
4239 static void
4240 output_addressed_constants (tree exp)
4242 tree tem;
4244 switch (TREE_CODE (exp))
4246 case ADDR_EXPR:
4247 case FDESC_EXPR:
4248 /* Go inside any operations that get_inner_reference can handle and see
4249 if what's inside is a constant: no need to do anything here for
4250 addresses of variables or functions. */
4251 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4252 tem = TREE_OPERAND (tem, 0))
4255 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4256 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4257 tem = DECL_INITIAL (tem);
4259 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4260 output_constant_def (tem, 0);
4262 if (TREE_CODE (tem) == MEM_REF)
4263 output_addressed_constants (TREE_OPERAND (tem, 0));
4264 break;
4266 case PLUS_EXPR:
4267 case POINTER_PLUS_EXPR:
4268 case MINUS_EXPR:
4269 output_addressed_constants (TREE_OPERAND (exp, 1));
4270 gcc_fallthrough ();
4272 CASE_CONVERT:
4273 case VIEW_CONVERT_EXPR:
4274 output_addressed_constants (TREE_OPERAND (exp, 0));
4275 break;
4277 case CONSTRUCTOR:
4279 unsigned HOST_WIDE_INT idx;
4280 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4281 if (tem != 0)
4282 output_addressed_constants (tem);
4284 break;
4286 default:
4287 break;
4291 /* Whether a constructor CTOR is a valid static constant initializer if all
4292 its elements are. This used to be internal to initializer_constant_valid_p
4293 and has been exposed to let other functions like categorize_ctor_elements
4294 evaluate the property while walking a constructor for other purposes. */
4296 bool
4297 constructor_static_from_elts_p (const_tree ctor)
4299 return (TREE_CONSTANT (ctor)
4300 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4301 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4302 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4305 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4306 tree *cache);
4308 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4309 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4310 which are valid when ENDTYPE is an integer of any size; in
4311 particular, this does not accept a pointer minus a constant. This
4312 returns null_pointer_node if the VALUE is an absolute constant
4313 which can be used to initialize a static variable. Otherwise it
4314 returns NULL. */
4316 static tree
4317 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4319 tree op0, op1;
4321 if (!INTEGRAL_TYPE_P (endtype))
4322 return NULL_TREE;
4324 op0 = TREE_OPERAND (value, 0);
4325 op1 = TREE_OPERAND (value, 1);
4327 /* Like STRIP_NOPS except allow the operand mode to widen. This
4328 works around a feature of fold that simplifies (int)(p1 - p2) to
4329 ((int)p1 - (int)p2) under the theory that the narrower operation
4330 is cheaper. */
4332 while (CONVERT_EXPR_P (op0)
4333 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4335 tree inner = TREE_OPERAND (op0, 0);
4336 if (inner == error_mark_node
4337 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4338 || (GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (op0)))
4339 > GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (inner)))))
4340 break;
4341 op0 = inner;
4344 while (CONVERT_EXPR_P (op1)
4345 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4347 tree inner = TREE_OPERAND (op1, 0);
4348 if (inner == error_mark_node
4349 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4350 || (GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (op1)))
4351 > GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (inner)))))
4352 break;
4353 op1 = inner;
4356 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4357 if (!op0)
4358 return NULL_TREE;
4360 op1 = initializer_constant_valid_p_1 (op1, endtype,
4361 cache ? cache + 2 : NULL);
4362 /* Both initializers must be known. */
4363 if (op1)
4365 if (op0 == op1
4366 && (op0 == null_pointer_node
4367 || TREE_CODE (value) == MINUS_EXPR))
4368 return null_pointer_node;
4370 /* Support differences between labels. */
4371 if (TREE_CODE (op0) == LABEL_DECL
4372 && TREE_CODE (op1) == LABEL_DECL)
4373 return null_pointer_node;
4375 if (TREE_CODE (op0) == STRING_CST
4376 && TREE_CODE (op1) == STRING_CST
4377 && operand_equal_p (op0, op1, 1))
4378 return null_pointer_node;
4381 return NULL_TREE;
4384 /* Helper function of initializer_constant_valid_p.
4385 Return nonzero if VALUE is a valid constant-valued expression
4386 for use in initializing a static variable; one that can be an
4387 element of a "constant" initializer.
4389 Return null_pointer_node if the value is absolute;
4390 if it is relocatable, return the variable that determines the relocation.
4391 We assume that VALUE has been folded as much as possible;
4392 therefore, we do not need to check for such things as
4393 arithmetic-combinations of integers.
4395 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4397 static tree
4398 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4400 tree ret;
4402 switch (TREE_CODE (value))
4404 case CONSTRUCTOR:
4405 if (constructor_static_from_elts_p (value))
4407 unsigned HOST_WIDE_INT idx;
4408 tree elt;
4409 bool absolute = true;
4411 if (cache && cache[0] == value)
4412 return cache[1];
4413 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4415 tree reloc;
4416 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4417 NULL);
4418 if (!reloc
4419 /* An absolute value is required with reverse SSO. */
4420 || (reloc != null_pointer_node
4421 && TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (value))
4422 && !AGGREGATE_TYPE_P (TREE_TYPE (elt))))
4424 if (cache)
4426 cache[0] = value;
4427 cache[1] = NULL_TREE;
4429 return NULL_TREE;
4431 if (reloc != null_pointer_node)
4432 absolute = false;
4434 /* For a non-absolute relocation, there is no single
4435 variable that can be "the variable that determines the
4436 relocation." */
4437 if (cache)
4439 cache[0] = value;
4440 cache[1] = absolute ? null_pointer_node : error_mark_node;
4442 return absolute ? null_pointer_node : error_mark_node;
4445 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4447 case INTEGER_CST:
4448 case VECTOR_CST:
4449 case REAL_CST:
4450 case FIXED_CST:
4451 case STRING_CST:
4452 case COMPLEX_CST:
4453 return null_pointer_node;
4455 case ADDR_EXPR:
4456 case FDESC_EXPR:
4458 tree op0 = staticp (TREE_OPERAND (value, 0));
4459 if (op0)
4461 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4462 to be a constant, this is old-skool offsetof-like nonsense. */
4463 if (TREE_CODE (op0) == INDIRECT_REF
4464 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4465 return null_pointer_node;
4466 /* Taking the address of a nested function involves a trampoline,
4467 unless we don't need or want one. */
4468 if (TREE_CODE (op0) == FUNCTION_DECL
4469 && DECL_STATIC_CHAIN (op0)
4470 && !TREE_NO_TRAMPOLINE (value))
4471 return NULL_TREE;
4472 /* "&{...}" requires a temporary to hold the constructed
4473 object. */
4474 if (TREE_CODE (op0) == CONSTRUCTOR)
4475 return NULL_TREE;
4477 return op0;
4480 case NON_LVALUE_EXPR:
4481 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4482 endtype, cache);
4484 case VIEW_CONVERT_EXPR:
4486 tree src = TREE_OPERAND (value, 0);
4487 tree src_type = TREE_TYPE (src);
4488 tree dest_type = TREE_TYPE (value);
4490 /* Allow view-conversions from aggregate to non-aggregate type only
4491 if the bit pattern is fully preserved afterwards; otherwise, the
4492 RTL expander won't be able to apply a subsequent transformation
4493 to the underlying constructor. */
4494 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4496 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4497 return initializer_constant_valid_p_1 (src, endtype, cache);
4498 else
4499 return NULL_TREE;
4502 /* Allow all other kinds of view-conversion. */
4503 return initializer_constant_valid_p_1 (src, endtype, cache);
4506 CASE_CONVERT:
4508 tree src = TREE_OPERAND (value, 0);
4509 tree src_type = TREE_TYPE (src);
4510 tree dest_type = TREE_TYPE (value);
4512 /* Allow conversions between pointer types, floating-point
4513 types, and offset types. */
4514 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4515 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4516 || (TREE_CODE (dest_type) == OFFSET_TYPE
4517 && TREE_CODE (src_type) == OFFSET_TYPE))
4518 return initializer_constant_valid_p_1 (src, endtype, cache);
4520 /* Allow length-preserving conversions between integer types. */
4521 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4522 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4523 return initializer_constant_valid_p_1 (src, endtype, cache);
4525 /* Allow conversions between other integer types only if
4526 explicit value. Don't allow sign-extension to a type larger
4527 than word and pointer, there aren't relocations that would
4528 allow to sign extend it to a wider type. */
4529 if (INTEGRAL_TYPE_P (dest_type)
4530 && INTEGRAL_TYPE_P (src_type)
4531 && (TYPE_UNSIGNED (src_type)
4532 || TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type)
4533 || TYPE_PRECISION (dest_type) <= BITS_PER_WORD
4534 || TYPE_PRECISION (dest_type) <= POINTER_SIZE))
4536 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4537 if (inner == null_pointer_node)
4538 return null_pointer_node;
4539 break;
4542 /* Allow (int) &foo provided int is as wide as a pointer. */
4543 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4544 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4545 return initializer_constant_valid_p_1 (src, endtype, cache);
4547 /* Likewise conversions from int to pointers, but also allow
4548 conversions from 0. */
4549 if ((POINTER_TYPE_P (dest_type)
4550 || TREE_CODE (dest_type) == OFFSET_TYPE)
4551 && INTEGRAL_TYPE_P (src_type))
4553 if (TREE_CODE (src) == INTEGER_CST
4554 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4555 return null_pointer_node;
4556 if (integer_zerop (src))
4557 return null_pointer_node;
4558 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4559 return initializer_constant_valid_p_1 (src, endtype, cache);
4562 /* Allow conversions to struct or union types if the value
4563 inside is okay. */
4564 if (TREE_CODE (dest_type) == RECORD_TYPE
4565 || TREE_CODE (dest_type) == UNION_TYPE)
4566 return initializer_constant_valid_p_1 (src, endtype, cache);
4568 break;
4570 case POINTER_PLUS_EXPR:
4571 case PLUS_EXPR:
4572 /* Any valid floating-point constants will have been folded by now;
4573 with -frounding-math we hit this with addition of two constants. */
4574 if (TREE_CODE (endtype) == REAL_TYPE)
4575 return NULL_TREE;
4576 if (cache && cache[0] == value)
4577 return cache[1];
4578 if (! INTEGRAL_TYPE_P (endtype)
4579 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4581 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4582 tree valid0
4583 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4584 endtype, ncache);
4585 tree valid1
4586 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4587 endtype, ncache + 2);
4588 /* If either term is absolute, use the other term's relocation. */
4589 if (valid0 == null_pointer_node)
4590 ret = valid1;
4591 else if (valid1 == null_pointer_node)
4592 ret = valid0;
4593 /* Support narrowing pointer differences. */
4594 else
4595 ret = narrowing_initializer_constant_valid_p (value, endtype,
4596 ncache);
4598 else
4599 /* Support narrowing pointer differences. */
4600 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4601 if (cache)
4603 cache[0] = value;
4604 cache[1] = ret;
4606 return ret;
4608 case MINUS_EXPR:
4609 if (TREE_CODE (endtype) == REAL_TYPE)
4610 return NULL_TREE;
4611 if (cache && cache[0] == value)
4612 return cache[1];
4613 if (! INTEGRAL_TYPE_P (endtype)
4614 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4616 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4617 tree valid0
4618 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4619 endtype, ncache);
4620 tree valid1
4621 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4622 endtype, ncache + 2);
4623 /* Win if second argument is absolute. */
4624 if (valid1 == null_pointer_node)
4625 ret = valid0;
4626 /* Win if both arguments have the same relocation.
4627 Then the value is absolute. */
4628 else if (valid0 == valid1 && valid0 != 0)
4629 ret = null_pointer_node;
4630 /* Since GCC guarantees that string constants are unique in the
4631 generated code, a subtraction between two copies of the same
4632 constant string is absolute. */
4633 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4634 && valid1 && TREE_CODE (valid1) == STRING_CST
4635 && operand_equal_p (valid0, valid1, 1))
4636 ret = null_pointer_node;
4637 /* Support narrowing differences. */
4638 else
4639 ret = narrowing_initializer_constant_valid_p (value, endtype,
4640 ncache);
4642 else
4643 /* Support narrowing differences. */
4644 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4645 if (cache)
4647 cache[0] = value;
4648 cache[1] = ret;
4650 return ret;
4652 default:
4653 break;
4656 return NULL_TREE;
4659 /* Return nonzero if VALUE is a valid constant-valued expression
4660 for use in initializing a static variable; one that can be an
4661 element of a "constant" initializer.
4663 Return null_pointer_node if the value is absolute;
4664 if it is relocatable, return the variable that determines the relocation.
4665 We assume that VALUE has been folded as much as possible;
4666 therefore, we do not need to check for such things as
4667 arithmetic-combinations of integers. */
4668 tree
4669 initializer_constant_valid_p (tree value, tree endtype, bool reverse)
4671 tree reloc = initializer_constant_valid_p_1 (value, endtype, NULL);
4673 /* An absolute value is required with reverse storage order. */
4674 if (reloc
4675 && reloc != null_pointer_node
4676 && reverse
4677 && !AGGREGATE_TYPE_P (endtype)
4678 && !VECTOR_TYPE_P (endtype))
4679 reloc = NULL_TREE;
4681 return reloc;
4684 /* Return true if VALUE is a valid constant-valued expression
4685 for use in initializing a static bit-field; one that can be
4686 an element of a "constant" initializer. */
4688 bool
4689 initializer_constant_valid_for_bitfield_p (tree value)
4691 /* For bitfields we support integer constants or possibly nested aggregates
4692 of such. */
4693 switch (TREE_CODE (value))
4695 case CONSTRUCTOR:
4697 unsigned HOST_WIDE_INT idx;
4698 tree elt;
4700 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4701 if (!initializer_constant_valid_for_bitfield_p (elt))
4702 return false;
4703 return true;
4706 case INTEGER_CST:
4707 case REAL_CST:
4708 return true;
4710 case VIEW_CONVERT_EXPR:
4711 case NON_LVALUE_EXPR:
4712 return
4713 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4715 default:
4716 break;
4719 return false;
4722 /* output_constructor outer state of relevance in recursive calls, typically
4723 for nested aggregate bitfields. */
4725 struct oc_outer_state {
4726 unsigned int bit_offset; /* current position in ... */
4727 int byte; /* ... the outer byte buffer. */
4730 static unsigned HOST_WIDE_INT
4731 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int, bool,
4732 oc_outer_state *);
4734 /* Output assembler code for constant EXP, with no label.
4735 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4736 Assumes output_addressed_constants has been done on EXP already.
4738 Generate at least SIZE bytes of assembler data, padding at the end
4739 with zeros if necessary. SIZE must always be specified. The returned
4740 value is the actual number of bytes of assembler data generated, which
4741 may be bigger than SIZE if the object contains a variable length field.
4743 SIZE is important for structure constructors,
4744 since trailing members may have been omitted from the constructor.
4745 It is also important for initialization of arrays from string constants
4746 since the full length of the string constant might not be wanted.
4747 It is also needed for initialization of unions, where the initializer's
4748 type is just one member, and that may not be as long as the union.
4750 There a case in which we would fail to output exactly SIZE bytes:
4751 for a structure constructor that wants to produce more than SIZE bytes.
4752 But such constructors will never be generated for any possible input.
4754 ALIGN is the alignment of the data in bits.
4756 If REVERSE is true, EXP is output in reverse storage order. */
4758 static unsigned HOST_WIDE_INT
4759 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align,
4760 bool reverse)
4762 enum tree_code code;
4763 unsigned HOST_WIDE_INT thissize;
4764 rtx cst;
4766 if (size == 0 || flag_syntax_only)
4767 return size;
4769 /* See if we're trying to initialize a pointer in a non-default mode
4770 to the address of some declaration somewhere. If the target says
4771 the mode is valid for pointers, assume the target has a way of
4772 resolving it. */
4773 if (TREE_CODE (exp) == NOP_EXPR
4774 && POINTER_TYPE_P (TREE_TYPE (exp))
4775 && targetm.addr_space.valid_pointer_mode
4776 (SCALAR_INT_TYPE_MODE (TREE_TYPE (exp)),
4777 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4779 tree saved_type = TREE_TYPE (exp);
4781 /* Peel off any intermediate conversions-to-pointer for valid
4782 pointer modes. */
4783 while (TREE_CODE (exp) == NOP_EXPR
4784 && POINTER_TYPE_P (TREE_TYPE (exp))
4785 && targetm.addr_space.valid_pointer_mode
4786 (SCALAR_INT_TYPE_MODE (TREE_TYPE (exp)),
4787 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4788 exp = TREE_OPERAND (exp, 0);
4790 /* If what we're left with is the address of something, we can
4791 convert the address to the final type and output it that
4792 way. */
4793 if (TREE_CODE (exp) == ADDR_EXPR)
4794 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4795 /* Likewise for constant ints. */
4796 else if (TREE_CODE (exp) == INTEGER_CST)
4797 exp = fold_convert (saved_type, exp);
4801 /* Eliminate any conversions since we'll be outputting the underlying
4802 constant. */
4803 while (CONVERT_EXPR_P (exp)
4804 || TREE_CODE (exp) == NON_LVALUE_EXPR
4805 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4807 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4808 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4810 /* Make sure eliminating the conversion is really a no-op, except with
4811 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4812 union types to allow for Ada unchecked unions. */
4813 if (type_size > op_size
4814 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4815 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4816 /* Keep the conversion. */
4817 break;
4818 else
4819 exp = TREE_OPERAND (exp, 0);
4822 code = TREE_CODE (TREE_TYPE (exp));
4823 thissize = int_size_in_bytes (TREE_TYPE (exp));
4825 /* Allow a constructor with no elements for any data type.
4826 This means to fill the space with zeros. */
4827 if (TREE_CODE (exp) == CONSTRUCTOR
4828 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4830 assemble_zeros (size);
4831 return size;
4834 if (TREE_CODE (exp) == FDESC_EXPR)
4836 #ifdef ASM_OUTPUT_FDESC
4837 HOST_WIDE_INT part = tree_to_shwi (TREE_OPERAND (exp, 1));
4838 tree decl = TREE_OPERAND (exp, 0);
4839 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4840 #else
4841 gcc_unreachable ();
4842 #endif
4843 return size;
4846 /* Now output the underlying data. If we've handling the padding, return.
4847 Otherwise, break and ensure SIZE is the size written. */
4848 switch (code)
4850 case BOOLEAN_TYPE:
4851 case INTEGER_TYPE:
4852 case ENUMERAL_TYPE:
4853 case POINTER_TYPE:
4854 case REFERENCE_TYPE:
4855 case OFFSET_TYPE:
4856 case FIXED_POINT_TYPE:
4857 case POINTER_BOUNDS_TYPE:
4858 case NULLPTR_TYPE:
4859 cst = expand_expr (exp, NULL_RTX, VOIDmode, EXPAND_INITIALIZER);
4860 if (reverse)
4861 cst = flip_storage_order (TYPE_MODE (TREE_TYPE (exp)), cst);
4862 if (!assemble_integer (cst, MIN (size, thissize), align, 0))
4863 error ("initializer for integer/fixed-point value is too complicated");
4864 break;
4866 case REAL_TYPE:
4867 if (TREE_CODE (exp) != REAL_CST)
4868 error ("initializer for floating value is not a floating constant");
4869 else
4870 assemble_real (TREE_REAL_CST (exp),
4871 SCALAR_FLOAT_TYPE_MODE (TREE_TYPE (exp)),
4872 align, reverse);
4873 break;
4875 case COMPLEX_TYPE:
4876 output_constant (TREE_REALPART (exp), thissize / 2, align, reverse);
4877 output_constant (TREE_IMAGPART (exp), thissize / 2,
4878 min_align (align, BITS_PER_UNIT * (thissize / 2)),
4879 reverse);
4880 break;
4882 case ARRAY_TYPE:
4883 case VECTOR_TYPE:
4884 switch (TREE_CODE (exp))
4886 case CONSTRUCTOR:
4887 return output_constructor (exp, size, align, reverse, NULL);
4888 case STRING_CST:
4889 thissize
4890 = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4891 assemble_string (TREE_STRING_POINTER (exp), thissize);
4892 break;
4893 case VECTOR_CST:
4895 scalar_mode inner = SCALAR_TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4896 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4897 int elt_size = GET_MODE_SIZE (inner);
4898 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align,
4899 reverse);
4900 thissize = elt_size;
4901 for (unsigned int i = 1; i < VECTOR_CST_NELTS (exp); i++)
4903 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign,
4904 reverse);
4905 thissize += elt_size;
4907 break;
4909 default:
4910 gcc_unreachable ();
4912 break;
4914 case RECORD_TYPE:
4915 case UNION_TYPE:
4916 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4917 return output_constructor (exp, size, align, reverse, NULL);
4919 case ERROR_MARK:
4920 return 0;
4922 default:
4923 gcc_unreachable ();
4926 if (size > thissize)
4927 assemble_zeros (size - thissize);
4929 return size;
4932 /* Subroutine of output_constructor, used for computing the size of
4933 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4934 type with an unspecified upper bound. */
4936 static unsigned HOST_WIDE_INT
4937 array_size_for_constructor (tree val)
4939 tree max_index;
4940 unsigned HOST_WIDE_INT cnt;
4941 tree index, value, tmp;
4942 offset_int i;
4944 /* This code used to attempt to handle string constants that are not
4945 arrays of single-bytes, but nothing else does, so there's no point in
4946 doing it here. */
4947 if (TREE_CODE (val) == STRING_CST)
4948 return TREE_STRING_LENGTH (val);
4950 max_index = NULL_TREE;
4951 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
4953 if (TREE_CODE (index) == RANGE_EXPR)
4954 index = TREE_OPERAND (index, 1);
4955 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
4956 max_index = index;
4959 if (max_index == NULL_TREE)
4960 return 0;
4962 /* Compute the total number of array elements. */
4963 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
4964 i = wi::to_offset (max_index) - wi::to_offset (tmp) + 1;
4966 /* Multiply by the array element unit size to find number of bytes. */
4967 i *= wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
4969 gcc_assert (wi::fits_uhwi_p (i));
4970 return i.to_uhwi ();
4973 /* Other datastructures + helpers for output_constructor. */
4975 /* output_constructor local state to support interaction with helpers. */
4977 struct oc_local_state {
4979 /* Received arguments. */
4980 tree exp; /* Constructor expression. */
4981 tree type; /* Type of constructor expression. */
4982 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */
4983 unsigned int align; /* Known initial alignment. */
4984 tree min_index; /* Lower bound if specified for an array. */
4986 /* Output processing state. */
4987 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */
4988 int byte; /* Part of a bitfield byte yet to be output. */
4989 int last_relative_index; /* Implicit or explicit index of the last
4990 array element output within a bitfield. */
4991 bool byte_buffer_in_use; /* Whether BYTE is in use. */
4992 bool reverse; /* Whether reverse storage order is in use. */
4994 /* Current element. */
4995 tree field; /* Current field decl in a record. */
4996 tree val; /* Current element value. */
4997 tree index; /* Current element index. */
5001 /* Helper for output_constructor. From the current LOCAL state, output a
5002 RANGE_EXPR element. */
5004 static void
5005 output_constructor_array_range (oc_local_state *local)
5007 unsigned HOST_WIDE_INT fieldsize
5008 = int_size_in_bytes (TREE_TYPE (local->type));
5010 HOST_WIDE_INT lo_index
5011 = tree_to_shwi (TREE_OPERAND (local->index, 0));
5012 HOST_WIDE_INT hi_index
5013 = tree_to_shwi (TREE_OPERAND (local->index, 1));
5014 HOST_WIDE_INT index;
5016 unsigned int align2
5017 = min_align (local->align, fieldsize * BITS_PER_UNIT);
5019 for (index = lo_index; index <= hi_index; index++)
5021 /* Output the element's initial value. */
5022 if (local->val == NULL_TREE)
5023 assemble_zeros (fieldsize);
5024 else
5025 fieldsize
5026 = output_constant (local->val, fieldsize, align2, local->reverse);
5028 /* Count its size. */
5029 local->total_bytes += fieldsize;
5033 /* Helper for output_constructor. From the current LOCAL state, output a
5034 field element that is not true bitfield or part of an outer one. */
5036 static void
5037 output_constructor_regular_field (oc_local_state *local)
5039 /* Field size and position. Since this structure is static, we know the
5040 positions are constant. */
5041 unsigned HOST_WIDE_INT fieldsize;
5042 HOST_WIDE_INT fieldpos;
5044 unsigned int align2;
5046 /* Output any buffered-up bit-fields preceding this element. */
5047 if (local->byte_buffer_in_use)
5049 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5050 local->total_bytes++;
5051 local->byte_buffer_in_use = false;
5054 if (local->index != NULL_TREE)
5056 /* Perform the index calculation in modulo arithmetic but
5057 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
5058 but we are using an unsigned sizetype. */
5059 unsigned prec = TYPE_PRECISION (sizetype);
5060 offset_int idx = wi::sext (wi::to_offset (local->index)
5061 - wi::to_offset (local->min_index), prec);
5062 fieldpos = (idx * wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (local->val))))
5063 .to_short_addr ();
5065 else if (local->field != NULL_TREE)
5066 fieldpos = int_byte_position (local->field);
5067 else
5068 fieldpos = 0;
5070 /* Advance to offset of this element.
5071 Note no alignment needed in an array, since that is guaranteed
5072 if each element has the proper size. */
5073 if (local->field != NULL_TREE || local->index != NULL_TREE)
5075 if (fieldpos > local->total_bytes)
5077 assemble_zeros (fieldpos - local->total_bytes);
5078 local->total_bytes = fieldpos;
5080 else
5081 /* Must not go backwards. */
5082 gcc_assert (fieldpos == local->total_bytes);
5085 /* Find the alignment of this element. */
5086 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
5088 /* Determine size this element should occupy. */
5089 if (local->field)
5091 fieldsize = 0;
5093 /* If this is an array with an unspecified upper bound,
5094 the initializer determines the size. */
5095 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
5096 but we cannot do this until the deprecated support for
5097 initializing zero-length array members is removed. */
5098 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
5099 && (!TYPE_DOMAIN (TREE_TYPE (local->field))
5100 || !TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field)))))
5102 fieldsize = array_size_for_constructor (local->val);
5103 /* Given a non-empty initialization, this field had better
5104 be last. Given a flexible array member, the next field
5105 on the chain is a TYPE_DECL of the enclosing struct. */
5106 const_tree next = DECL_CHAIN (local->field);
5107 gcc_assert (!fieldsize || !next || TREE_CODE (next) != FIELD_DECL);
5109 else
5110 fieldsize = tree_to_uhwi (DECL_SIZE_UNIT (local->field));
5112 else
5113 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
5115 /* Output the element's initial value. */
5116 if (local->val == NULL_TREE)
5117 assemble_zeros (fieldsize);
5118 else
5119 fieldsize
5120 = output_constant (local->val, fieldsize, align2, local->reverse);
5122 /* Count its size. */
5123 local->total_bytes += fieldsize;
5126 /* Helper for output_constructor. From the LOCAL state, output an element
5127 that is a true bitfield or part of an outer one. BIT_OFFSET is the offset
5128 from the start of a possibly ongoing outer byte buffer. */
5130 static void
5131 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
5133 /* Bit size of this element. */
5134 HOST_WIDE_INT ebitsize
5135 = (local->field
5136 ? tree_to_uhwi (DECL_SIZE (local->field))
5137 : tree_to_uhwi (TYPE_SIZE (TREE_TYPE (local->type))));
5139 /* Relative index of this element if this is an array component. */
5140 HOST_WIDE_INT relative_index
5141 = (!local->field
5142 ? (local->index
5143 ? (tree_to_shwi (local->index)
5144 - tree_to_shwi (local->min_index))
5145 : local->last_relative_index + 1)
5146 : 0);
5148 /* Bit position of this element from the start of the containing
5149 constructor. */
5150 HOST_WIDE_INT constructor_relative_ebitpos
5151 = (local->field
5152 ? int_bit_position (local->field)
5153 : ebitsize * relative_index);
5155 /* Bit position of this element from the start of a possibly ongoing
5156 outer byte buffer. */
5157 HOST_WIDE_INT byte_relative_ebitpos
5158 = bit_offset + constructor_relative_ebitpos;
5160 /* From the start of a possibly ongoing outer byte buffer, offsets to
5161 the first bit of this element and to the first bit past the end of
5162 this element. */
5163 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
5164 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
5166 local->last_relative_index = relative_index;
5168 if (local->val == NULL_TREE)
5169 local->val = integer_zero_node;
5171 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
5172 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
5173 local->val = TREE_OPERAND (local->val, 0);
5175 if (TREE_CODE (local->val) != INTEGER_CST
5176 && TREE_CODE (local->val) != CONSTRUCTOR)
5178 error ("invalid initial value for member %qE", DECL_NAME (local->field));
5179 return;
5182 /* If this field does not start in this (or next) byte, skip some bytes. */
5183 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5185 /* Output remnant of any bit field in previous bytes. */
5186 if (local->byte_buffer_in_use)
5188 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5189 local->total_bytes++;
5190 local->byte_buffer_in_use = false;
5193 /* If still not at proper byte, advance to there. */
5194 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5196 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
5197 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
5198 local->total_bytes = next_offset / BITS_PER_UNIT;
5202 /* Set up the buffer if necessary. */
5203 if (!local->byte_buffer_in_use)
5205 local->byte = 0;
5206 if (ebitsize > 0)
5207 local->byte_buffer_in_use = true;
5210 /* If this is nested constructor, recurse passing the bit offset and the
5211 pending data, then retrieve the new pending data afterwards. */
5212 if (TREE_CODE (local->val) == CONSTRUCTOR)
5214 oc_outer_state temp_state;
5215 temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5216 temp_state.byte = local->byte;
5217 local->total_bytes
5218 += output_constructor (local->val, 0, 0, local->reverse, &temp_state);
5219 local->byte = temp_state.byte;
5220 return;
5223 /* Otherwise, we must split the element into pieces that fall within
5224 separate bytes, and combine each byte with previous or following
5225 bit-fields. */
5226 while (next_offset < end_offset)
5228 int this_time;
5229 int shift;
5230 HOST_WIDE_INT value;
5231 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5232 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5234 /* Advance from byte to byte within this element when necessary. */
5235 while (next_byte != local->total_bytes)
5237 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5238 local->total_bytes++;
5239 local->byte = 0;
5242 /* Number of bits we can process at once (all part of the same byte). */
5243 this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5244 if (local->reverse ? !BYTES_BIG_ENDIAN : BYTES_BIG_ENDIAN)
5246 /* For big-endian data, take the most significant bits (of the
5247 bits that are significant) first and put them into bytes from
5248 the most significant end. */
5249 shift = end_offset - next_offset - this_time;
5251 /* Don't try to take a bunch of bits that cross
5252 the word boundary in the INTEGER_CST. We can
5253 only select bits from one element. */
5254 if ((shift / HOST_BITS_PER_WIDE_INT)
5255 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5257 const int end = shift + this_time - 1;
5258 shift = end & -HOST_BITS_PER_WIDE_INT;
5259 this_time = end - shift + 1;
5262 /* Now get the bits from the appropriate constant word. */
5263 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5264 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5266 /* Get the result. This works only when:
5267 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5268 local->byte |= (((value >> shift)
5269 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5270 << (BITS_PER_UNIT - this_time - next_bit));
5272 else
5274 /* On little-endian machines, take the least significant bits of
5275 the value first and pack them starting at the least significant
5276 bits of the bytes. */
5277 shift = next_offset - byte_relative_ebitpos;
5279 /* Don't try to take a bunch of bits that cross
5280 the word boundary in the INTEGER_CST. We can
5281 only select bits from one element. */
5282 if ((shift / HOST_BITS_PER_WIDE_INT)
5283 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5284 this_time
5285 = HOST_BITS_PER_WIDE_INT - (shift & (HOST_BITS_PER_WIDE_INT - 1));
5287 /* Now get the bits from the appropriate constant word. */
5288 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5289 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5291 /* Get the result. This works only when:
5292 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5293 local->byte |= (((value >> shift)
5294 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5295 << next_bit);
5298 next_offset += this_time;
5299 local->byte_buffer_in_use = true;
5303 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5304 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5305 caller output state of relevance in recursive invocations. */
5307 static unsigned HOST_WIDE_INT
5308 output_constructor (tree exp, unsigned HOST_WIDE_INT size, unsigned int align,
5309 bool reverse, oc_outer_state *outer)
5311 unsigned HOST_WIDE_INT cnt;
5312 constructor_elt *ce;
5313 oc_local_state local;
5315 /* Setup our local state to communicate with helpers. */
5316 local.exp = exp;
5317 local.type = TREE_TYPE (exp);
5318 local.size = size;
5319 local.align = align;
5320 if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5321 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5322 else
5323 local.min_index = integer_zero_node;
5325 local.total_bytes = 0;
5326 local.byte_buffer_in_use = outer != NULL;
5327 local.byte = outer ? outer->byte : 0;
5328 local.last_relative_index = -1;
5329 /* The storage order is specified for every aggregate type. */
5330 if (AGGREGATE_TYPE_P (local.type))
5331 local.reverse = TYPE_REVERSE_STORAGE_ORDER (local.type);
5332 else
5333 local.reverse = reverse;
5335 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5337 /* As CE goes through the elements of the constant, FIELD goes through the
5338 structure fields if the constant is a structure. If the constant is a
5339 union, we override this by getting the field from the TREE_LIST element.
5340 But the constant could also be an array. Then FIELD is zero.
5342 There is always a maximum of one element in the chain LINK for unions
5343 (even if the initializer in a source program incorrectly contains
5344 more one). */
5346 if (TREE_CODE (local.type) == RECORD_TYPE)
5347 local.field = TYPE_FIELDS (local.type);
5348 else
5349 local.field = NULL_TREE;
5351 for (cnt = 0;
5352 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5353 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5355 local.val = ce->value;
5356 local.index = NULL_TREE;
5358 /* The element in a union constructor specifies the proper field
5359 or index. */
5360 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5361 local.field = ce->index;
5363 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5364 local.index = ce->index;
5366 if (local.field && flag_verbose_asm)
5367 fprintf (asm_out_file, "%s %s:\n",
5368 ASM_COMMENT_START,
5369 DECL_NAME (local.field)
5370 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5371 : "<anonymous>");
5373 /* Eliminate the marker that makes a cast not be an lvalue. */
5374 if (local.val != NULL_TREE)
5375 STRIP_NOPS (local.val);
5377 /* Output the current element, using the appropriate helper ... */
5379 /* For an array slice not part of an outer bitfield. */
5380 if (!outer
5381 && local.index != NULL_TREE
5382 && TREE_CODE (local.index) == RANGE_EXPR)
5383 output_constructor_array_range (&local);
5385 /* For a field that is neither a true bitfield nor part of an outer one,
5386 known to be at least byte aligned and multiple-of-bytes long. */
5387 else if (!outer
5388 && (local.field == NULL_TREE
5389 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5390 output_constructor_regular_field (&local);
5392 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5393 supported for scalar fields, so we may need to convert first. */
5394 else
5396 if (TREE_CODE (local.val) == REAL_CST)
5397 local.val
5398 = fold_unary (VIEW_CONVERT_EXPR,
5399 build_nonstandard_integer_type
5400 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5401 local.val);
5402 output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5406 /* If we are not at toplevel, save the pending data for our caller.
5407 Otherwise output the pending data and padding zeros as needed. */
5408 if (outer)
5409 outer->byte = local.byte;
5410 else
5412 if (local.byte_buffer_in_use)
5414 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5415 local.total_bytes++;
5418 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5420 assemble_zeros (local.size - local.total_bytes);
5421 local.total_bytes = local.size;
5425 return local.total_bytes;
5428 /* Mark DECL as weak. */
5430 static void
5431 mark_weak (tree decl)
5433 if (DECL_WEAK (decl))
5434 return;
5436 struct symtab_node *n = symtab_node::get (decl);
5437 if (n && n->refuse_visibility_changes)
5438 error ("%+qD declared weak after being used", decl);
5439 DECL_WEAK (decl) = 1;
5441 if (DECL_RTL_SET_P (decl)
5442 && MEM_P (DECL_RTL (decl))
5443 && XEXP (DECL_RTL (decl), 0)
5444 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5445 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5448 /* Merge weak status between NEWDECL and OLDDECL. */
5450 void
5451 merge_weak (tree newdecl, tree olddecl)
5453 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5455 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5457 tree *pwd;
5458 /* We put the NEWDECL on the weak_decls list at some point
5459 and OLDDECL as well. Keep just OLDDECL on the list. */
5460 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5461 if (TREE_VALUE (*pwd) == newdecl)
5463 *pwd = TREE_CHAIN (*pwd);
5464 break;
5467 return;
5470 if (DECL_WEAK (newdecl))
5472 tree wd;
5474 /* NEWDECL is weak, but OLDDECL is not. */
5476 /* If we already output the OLDDECL, we're in trouble; we can't
5477 go back and make it weak. This should never happen in
5478 unit-at-a-time compilation. */
5479 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5481 /* If we've already generated rtl referencing OLDDECL, we may
5482 have done so in a way that will not function properly with
5483 a weak symbol. Again in unit-at-a-time this should be
5484 impossible. */
5485 gcc_assert (!TREE_USED (olddecl)
5486 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5488 /* PR 49899: You cannot convert a static function into a weak, public function. */
5489 if (! TREE_PUBLIC (olddecl) && TREE_PUBLIC (newdecl))
5490 error ("weak declaration of %q+D being applied to a already "
5491 "existing, static definition", newdecl);
5493 if (TARGET_SUPPORTS_WEAK)
5495 /* We put the NEWDECL on the weak_decls list at some point.
5496 Replace it with the OLDDECL. */
5497 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5498 if (TREE_VALUE (wd) == newdecl)
5500 TREE_VALUE (wd) = olddecl;
5501 break;
5503 /* We may not find the entry on the list. If NEWDECL is a
5504 weak alias, then we will have already called
5505 globalize_decl to remove the entry; in that case, we do
5506 not need to do anything. */
5509 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5510 mark_weak (olddecl);
5512 else
5513 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5514 weak. Just update NEWDECL to indicate that it's weak too. */
5515 mark_weak (newdecl);
5518 /* Declare DECL to be a weak symbol. */
5520 void
5521 declare_weak (tree decl)
5523 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5524 if (! TREE_PUBLIC (decl))
5526 error ("weak declaration of %q+D must be public", decl);
5527 return;
5529 else if (!TARGET_SUPPORTS_WEAK)
5530 warning (0, "weak declaration of %q+D not supported", decl);
5532 mark_weak (decl);
5533 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5534 DECL_ATTRIBUTES (decl)
5535 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5538 static void
5539 weak_finish_1 (tree decl)
5541 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5542 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5543 #endif
5545 if (! TREE_USED (decl))
5546 return;
5548 #ifdef ASM_WEAKEN_DECL
5549 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5550 #else
5551 #ifdef ASM_WEAKEN_LABEL
5552 ASM_WEAKEN_LABEL (asm_out_file, name);
5553 #else
5554 #ifdef ASM_OUTPUT_WEAK_ALIAS
5556 static bool warn_once = 0;
5557 if (! warn_once)
5559 warning (0, "only weak aliases are supported in this configuration");
5560 warn_once = 1;
5562 return;
5564 #endif
5565 #endif
5566 #endif
5569 /* Fiven an assembly name, find the decl it is associated with. */
5570 static tree
5571 find_decl (tree target)
5573 symtab_node *node = symtab_node::get_for_asmname (target);
5574 if (node)
5575 return node->decl;
5576 return NULL_TREE;
5579 /* This TREE_LIST contains weakref targets. */
5581 static GTY(()) tree weakref_targets;
5583 /* Emit any pending weak declarations. */
5585 void
5586 weak_finish (void)
5588 tree t;
5590 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5592 tree alias_decl = TREE_PURPOSE (t);
5593 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5595 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5596 /* Remove alias_decl from the weak list, but leave entries for
5597 the target alone. */
5598 target = NULL_TREE;
5599 #ifndef ASM_OUTPUT_WEAKREF
5600 else if (! TREE_SYMBOL_REFERENCED (target))
5602 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5603 defined, otherwise we and weak_finish_1 would use
5604 different macros. */
5605 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5606 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5607 # else
5608 tree decl = find_decl (target);
5610 if (! decl)
5612 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5613 TREE_CODE (alias_decl), target,
5614 TREE_TYPE (alias_decl));
5616 DECL_EXTERNAL (decl) = 1;
5617 TREE_PUBLIC (decl) = 1;
5618 DECL_ARTIFICIAL (decl) = 1;
5619 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5620 TREE_USED (decl) = 1;
5623 weak_finish_1 (decl);
5624 # endif
5626 #endif
5629 tree *p;
5630 tree t2;
5632 /* Remove the alias and the target from the pending weak list
5633 so that we do not emit any .weak directives for the former,
5634 nor multiple .weak directives for the latter. */
5635 for (p = &weak_decls; (t2 = *p) ; )
5637 if (TREE_VALUE (t2) == alias_decl
5638 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5639 *p = TREE_CHAIN (t2);
5640 else
5641 p = &TREE_CHAIN (t2);
5644 /* Remove other weakrefs to the same target, to speed things up. */
5645 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5647 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5648 *p = TREE_CHAIN (t2);
5649 else
5650 p = &TREE_CHAIN (t2);
5655 for (t = weak_decls; t; t = TREE_CHAIN (t))
5657 tree decl = TREE_VALUE (t);
5659 weak_finish_1 (decl);
5663 /* Emit the assembly bits to indicate that DECL is globally visible. */
5665 static void
5666 globalize_decl (tree decl)
5669 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5670 if (DECL_WEAK (decl))
5672 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5673 tree *p, t;
5675 #ifdef ASM_WEAKEN_DECL
5676 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5677 #else
5678 ASM_WEAKEN_LABEL (asm_out_file, name);
5679 #endif
5681 /* Remove this function from the pending weak list so that
5682 we do not emit multiple .weak directives for it. */
5683 for (p = &weak_decls; (t = *p) ; )
5685 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5686 *p = TREE_CHAIN (t);
5687 else
5688 p = &TREE_CHAIN (t);
5691 /* Remove weakrefs to the same target from the pending weakref
5692 list, for the same reason. */
5693 for (p = &weakref_targets; (t = *p) ; )
5695 if (DECL_ASSEMBLER_NAME (decl)
5696 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5697 *p = TREE_CHAIN (t);
5698 else
5699 p = &TREE_CHAIN (t);
5702 return;
5704 #endif
5706 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5709 vec<alias_pair, va_gc> *alias_pairs;
5711 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5712 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5713 tree node is DECL to have the value of the tree node TARGET. */
5715 void
5716 do_assemble_alias (tree decl, tree target)
5718 tree id;
5720 /* Emulated TLS had better not get this var. */
5721 gcc_assert (!(!targetm.have_tls
5722 && VAR_P (decl)
5723 && DECL_THREAD_LOCAL_P (decl)));
5725 if (TREE_ASM_WRITTEN (decl))
5726 return;
5728 id = DECL_ASSEMBLER_NAME (decl);
5729 ultimate_transparent_alias_target (&id);
5730 ultimate_transparent_alias_target (&target);
5732 /* We must force creation of DECL_RTL for debug info generation, even though
5733 we don't use it here. */
5734 make_decl_rtl (decl);
5736 TREE_ASM_WRITTEN (decl) = 1;
5737 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5738 TREE_ASM_WRITTEN (id) = 1;
5740 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5742 if (!TREE_SYMBOL_REFERENCED (target))
5743 weakref_targets = tree_cons (decl, target, weakref_targets);
5745 #ifdef ASM_OUTPUT_WEAKREF
5746 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5747 IDENTIFIER_POINTER (id),
5748 IDENTIFIER_POINTER (target));
5749 #else
5750 if (!TARGET_SUPPORTS_WEAK)
5752 error_at (DECL_SOURCE_LOCATION (decl),
5753 "weakref is not supported in this configuration");
5754 return;
5756 #endif
5757 return;
5760 #ifdef ASM_OUTPUT_DEF
5761 tree orig_decl = decl;
5763 if (TREE_CODE (decl) == FUNCTION_DECL
5764 && cgraph_node::get (decl)->instrumentation_clone
5765 && cgraph_node::get (decl)->instrumented_version)
5766 orig_decl = cgraph_node::get (decl)->instrumented_version->decl;
5768 /* Make name accessible from other files, if appropriate. */
5770 if (TREE_PUBLIC (decl) || TREE_PUBLIC (orig_decl))
5772 globalize_decl (decl);
5773 maybe_assemble_visibility (decl);
5775 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5777 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5778 if (targetm.has_ifunc_p ())
5779 ASM_OUTPUT_TYPE_DIRECTIVE
5780 (asm_out_file, IDENTIFIER_POINTER (id),
5781 IFUNC_ASM_TYPE);
5782 else
5783 #endif
5784 error_at (DECL_SOURCE_LOCATION (decl),
5785 "ifunc is not supported on this target");
5788 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5789 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5790 # else
5791 ASM_OUTPUT_DEF (asm_out_file,
5792 IDENTIFIER_POINTER (id),
5793 IDENTIFIER_POINTER (target));
5794 # endif
5795 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5797 const char *name;
5798 tree *p, t;
5800 name = IDENTIFIER_POINTER (id);
5801 # ifdef ASM_WEAKEN_DECL
5802 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5803 # else
5804 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5805 # endif
5806 /* Remove this function from the pending weak list so that
5807 we do not emit multiple .weak directives for it. */
5808 for (p = &weak_decls; (t = *p) ; )
5809 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t))
5810 || id == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5811 *p = TREE_CHAIN (t);
5812 else
5813 p = &TREE_CHAIN (t);
5815 /* Remove weakrefs to the same target from the pending weakref
5816 list, for the same reason. */
5817 for (p = &weakref_targets; (t = *p) ; )
5819 if (id == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5820 *p = TREE_CHAIN (t);
5821 else
5822 p = &TREE_CHAIN (t);
5825 #endif
5828 /* Emit an assembler directive to make the symbol for DECL an alias to
5829 the symbol for TARGET. */
5831 void
5832 assemble_alias (tree decl, tree target)
5834 tree target_decl;
5836 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5838 tree alias = DECL_ASSEMBLER_NAME (decl);
5840 ultimate_transparent_alias_target (&target);
5842 if (alias == target)
5843 error ("weakref %q+D ultimately targets itself", decl);
5844 if (TREE_PUBLIC (decl))
5845 error ("weakref %q+D must have static linkage", decl);
5847 else
5849 #if !defined (ASM_OUTPUT_DEF)
5850 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5851 error_at (DECL_SOURCE_LOCATION (decl),
5852 "alias definitions not supported in this configuration");
5853 TREE_ASM_WRITTEN (decl) = 1;
5854 return;
5855 # else
5856 if (!DECL_WEAK (decl))
5858 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5859 error_at (DECL_SOURCE_LOCATION (decl),
5860 "ifunc is not supported in this configuration");
5861 else
5862 error_at (DECL_SOURCE_LOCATION (decl),
5863 "only weak aliases are supported in this configuration");
5864 TREE_ASM_WRITTEN (decl) = 1;
5865 return;
5867 # endif
5868 #endif
5870 TREE_USED (decl) = 1;
5872 /* Allow aliases to aliases. */
5873 if (TREE_CODE (decl) == FUNCTION_DECL)
5874 cgraph_node::get_create (decl)->alias = true;
5875 else
5876 varpool_node::get_create (decl)->alias = true;
5878 /* If the target has already been emitted, we don't have to queue the
5879 alias. This saves a tad of memory. */
5880 if (symtab->global_info_ready)
5881 target_decl = find_decl (target);
5882 else
5883 target_decl= NULL;
5884 if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5885 || symtab->state >= EXPANSION)
5886 do_assemble_alias (decl, target);
5887 else
5889 alias_pair p = {decl, target};
5890 vec_safe_push (alias_pairs, p);
5894 /* Record and output a table of translations from original function
5895 to its transaction aware clone. Note that tm_pure functions are
5896 considered to be their own clone. */
5898 struct tm_clone_hasher : ggc_cache_ptr_hash<tree_map>
5900 static hashval_t hash (tree_map *m) { return tree_map_hash (m); }
5901 static bool equal (tree_map *a, tree_map *b) { return tree_map_eq (a, b); }
5903 static int
5904 keep_cache_entry (tree_map *&e)
5906 return ggc_marked_p (e->base.from);
5910 static GTY((cache)) hash_table<tm_clone_hasher> *tm_clone_hash;
5912 void
5913 record_tm_clone_pair (tree o, tree n)
5915 struct tree_map **slot, *h;
5917 if (tm_clone_hash == NULL)
5918 tm_clone_hash = hash_table<tm_clone_hasher>::create_ggc (32);
5920 h = ggc_alloc<tree_map> ();
5921 h->hash = htab_hash_pointer (o);
5922 h->base.from = o;
5923 h->to = n;
5925 slot = tm_clone_hash->find_slot_with_hash (h, h->hash, INSERT);
5926 *slot = h;
5929 tree
5930 get_tm_clone_pair (tree o)
5932 if (tm_clone_hash)
5934 struct tree_map *h, in;
5936 in.base.from = o;
5937 in.hash = htab_hash_pointer (o);
5938 h = tm_clone_hash->find_with_hash (&in, in.hash);
5939 if (h)
5940 return h->to;
5942 return NULL_TREE;
5945 struct tm_alias_pair
5947 unsigned int uid;
5948 tree from;
5949 tree to;
5953 /* Dump the actual pairs to the .tm_clone_table section. */
5955 static void
5956 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
5958 unsigned i;
5959 tm_alias_pair *p;
5960 bool switched = false;
5962 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
5964 tree src = p->from;
5965 tree dst = p->to;
5966 struct cgraph_node *src_n = cgraph_node::get (src);
5967 struct cgraph_node *dst_n = cgraph_node::get (dst);
5969 /* The function ipa_tm_create_version() marks the clone as needed if
5970 the original function was needed. But we also mark the clone as
5971 needed if we ever called the clone indirectly through
5972 TM_GETTMCLONE. If neither of these are true, we didn't generate
5973 a clone, and we didn't call it indirectly... no sense keeping it
5974 in the clone table. */
5975 if (!dst_n || !dst_n->definition)
5976 continue;
5978 /* This covers the case where we have optimized the original
5979 function away, and only access the transactional clone. */
5980 if (!src_n || !src_n->definition)
5981 continue;
5983 if (!switched)
5985 switch_to_section (targetm.asm_out.tm_clone_table_section ());
5986 assemble_align (POINTER_SIZE);
5987 switched = true;
5990 assemble_integer (XEXP (DECL_RTL (src), 0),
5991 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
5992 assemble_integer (XEXP (DECL_RTL (dst), 0),
5993 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
5997 /* Provide a default for the tm_clone_table section. */
5999 section *
6000 default_clone_table_section (void)
6002 return get_named_section (NULL, ".tm_clone_table", 3);
6005 /* Helper comparison function for qsorting by the DECL_UID stored in
6006 alias_pair->emitted_diags. */
6008 static int
6009 tm_alias_pair_cmp (const void *x, const void *y)
6011 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
6012 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
6013 if (p1->uid < p2->uid)
6014 return -1;
6015 if (p1->uid > p2->uid)
6016 return 1;
6017 return 0;
6020 void
6021 finish_tm_clone_pairs (void)
6023 vec<tm_alias_pair> tm_alias_pairs = vNULL;
6025 if (tm_clone_hash == NULL)
6026 return;
6028 /* We need a determenistic order for the .tm_clone_table, otherwise
6029 we will get bootstrap comparison failures, so dump the hash table
6030 to a vector, sort it, and dump the vector. */
6032 /* Dump the hashtable to a vector. */
6033 tree_map *map;
6034 hash_table<tm_clone_hasher>::iterator iter;
6035 FOR_EACH_HASH_TABLE_ELEMENT (*tm_clone_hash, map, tree_map *, iter)
6037 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
6038 tm_alias_pairs.safe_push (p);
6040 /* Sort it. */
6041 tm_alias_pairs.qsort (tm_alias_pair_cmp);
6043 /* Dump it. */
6044 dump_tm_clone_pairs (tm_alias_pairs);
6046 tm_clone_hash->empty ();
6047 tm_clone_hash = NULL;
6048 tm_alias_pairs.release ();
6052 /* Emit an assembler directive to set symbol for DECL visibility to
6053 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
6055 void
6056 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
6057 int vis ATTRIBUTE_UNUSED)
6059 #ifdef HAVE_GAS_HIDDEN
6060 static const char * const visibility_types[] = {
6061 NULL, "protected", "hidden", "internal"
6064 const char *name, *type;
6065 tree id;
6067 id = DECL_ASSEMBLER_NAME (decl);
6068 ultimate_transparent_alias_target (&id);
6069 name = IDENTIFIER_POINTER (id);
6071 type = visibility_types[vis];
6073 fprintf (asm_out_file, "\t.%s\t", type);
6074 assemble_name (asm_out_file, name);
6075 fprintf (asm_out_file, "\n");
6076 #else
6077 if (!DECL_ARTIFICIAL (decl))
6078 warning (OPT_Wattributes, "visibility attribute not supported "
6079 "in this configuration; ignored");
6080 #endif
6083 /* A helper function to call assemble_visibility when needed for a decl. */
6086 maybe_assemble_visibility (tree decl)
6088 enum symbol_visibility vis = DECL_VISIBILITY (decl);
6090 if (TREE_CODE (decl) == FUNCTION_DECL
6091 && cgraph_node::get (decl)
6092 && cgraph_node::get (decl)->instrumentation_clone
6093 && cgraph_node::get (decl)->instrumented_version)
6094 vis = DECL_VISIBILITY (cgraph_node::get (decl)->instrumented_version->decl);
6096 if (vis != VISIBILITY_DEFAULT)
6098 targetm.asm_out.assemble_visibility (decl, vis);
6099 return 1;
6101 else
6102 return 0;
6105 /* Returns 1 if the target configuration supports defining public symbols
6106 so that one of them will be chosen at link time instead of generating a
6107 multiply-defined symbol error, whether through the use of weak symbols or
6108 a target-specific mechanism for having duplicates discarded. */
6111 supports_one_only (void)
6113 if (SUPPORTS_ONE_ONLY)
6114 return 1;
6115 return TARGET_SUPPORTS_WEAK;
6118 /* Set up DECL as a public symbol that can be defined in multiple
6119 translation units without generating a linker error. */
6121 void
6122 make_decl_one_only (tree decl, tree comdat_group)
6124 struct symtab_node *symbol;
6125 gcc_assert (VAR_OR_FUNCTION_DECL_P (decl));
6127 TREE_PUBLIC (decl) = 1;
6129 if (VAR_P (decl))
6130 symbol = varpool_node::get_create (decl);
6131 else
6132 symbol = cgraph_node::get_create (decl);
6134 if (SUPPORTS_ONE_ONLY)
6136 #ifdef MAKE_DECL_ONE_ONLY
6137 MAKE_DECL_ONE_ONLY (decl);
6138 #endif
6139 symbol->set_comdat_group (comdat_group);
6141 else if (VAR_P (decl)
6142 && (DECL_INITIAL (decl) == 0
6143 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
6144 DECL_COMMON (decl) = 1;
6145 else
6147 gcc_assert (TARGET_SUPPORTS_WEAK);
6148 DECL_WEAK (decl) = 1;
6152 void
6153 init_varasm_once (void)
6155 section_htab = hash_table<section_hasher>::create_ggc (31);
6156 object_block_htab = hash_table<object_block_hasher>::create_ggc (31);
6157 const_desc_htab = hash_table<tree_descriptor_hasher>::create_ggc (1009);
6159 shared_constant_pool = create_constant_pool ();
6161 #ifdef TEXT_SECTION_ASM_OP
6162 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
6163 TEXT_SECTION_ASM_OP);
6164 #endif
6166 #ifdef DATA_SECTION_ASM_OP
6167 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
6168 DATA_SECTION_ASM_OP);
6169 #endif
6171 #ifdef SDATA_SECTION_ASM_OP
6172 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
6173 SDATA_SECTION_ASM_OP);
6174 #endif
6176 #ifdef READONLY_DATA_SECTION_ASM_OP
6177 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
6178 READONLY_DATA_SECTION_ASM_OP);
6179 #endif
6181 #ifdef CTORS_SECTION_ASM_OP
6182 ctors_section = get_unnamed_section (0, output_section_asm_op,
6183 CTORS_SECTION_ASM_OP);
6184 #endif
6186 #ifdef DTORS_SECTION_ASM_OP
6187 dtors_section = get_unnamed_section (0, output_section_asm_op,
6188 DTORS_SECTION_ASM_OP);
6189 #endif
6191 #ifdef BSS_SECTION_ASM_OP
6192 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6193 output_section_asm_op,
6194 BSS_SECTION_ASM_OP);
6195 #endif
6197 #ifdef SBSS_SECTION_ASM_OP
6198 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6199 output_section_asm_op,
6200 SBSS_SECTION_ASM_OP);
6201 #endif
6203 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6204 | SECTION_COMMON, emit_tls_common);
6205 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6206 | SECTION_COMMON, emit_local);
6207 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6208 | SECTION_COMMON, emit_common);
6210 #if defined ASM_OUTPUT_ALIGNED_BSS
6211 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
6212 emit_bss);
6213 #endif
6215 targetm.asm_out.init_sections ();
6217 if (readonly_data_section == NULL)
6218 readonly_data_section = text_section;
6220 #ifdef ASM_OUTPUT_EXTERNAL
6221 pending_assemble_externals_set = new hash_set<tree>;
6222 #endif
6225 enum tls_model
6226 decl_default_tls_model (const_tree decl)
6228 enum tls_model kind;
6229 bool is_local;
6231 is_local = targetm.binds_local_p (decl);
6232 if (!flag_shlib)
6234 if (is_local)
6235 kind = TLS_MODEL_LOCAL_EXEC;
6236 else
6237 kind = TLS_MODEL_INITIAL_EXEC;
6240 /* Local dynamic is inefficient when we're not combining the
6241 parts of the address. */
6242 else if (optimize && is_local)
6243 kind = TLS_MODEL_LOCAL_DYNAMIC;
6244 else
6245 kind = TLS_MODEL_GLOBAL_DYNAMIC;
6246 if (kind < flag_tls_default)
6247 kind = flag_tls_default;
6249 return kind;
6252 /* Select a set of attributes for section NAME based on the properties
6253 of DECL and whether or not RELOC indicates that DECL's initializer
6254 might contain runtime relocations.
6256 We make the section read-only and executable for a function decl,
6257 read-only for a const data decl, and writable for a non-const data decl. */
6259 unsigned int
6260 default_section_type_flags (tree decl, const char *name, int reloc)
6262 unsigned int flags;
6264 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6265 flags = SECTION_CODE;
6266 else if (decl)
6268 enum section_category category
6269 = categorize_decl_for_section (decl, reloc);
6270 if (decl_readonly_section_1 (category))
6271 flags = 0;
6272 else if (category == SECCAT_DATA_REL_RO
6273 || category == SECCAT_DATA_REL_RO_LOCAL)
6274 flags = SECTION_WRITE | SECTION_RELRO;
6275 else
6276 flags = SECTION_WRITE;
6278 else
6280 flags = SECTION_WRITE;
6281 if (strcmp (name, ".data.rel.ro") == 0
6282 || strcmp (name, ".data.rel.ro.local") == 0)
6283 flags |= SECTION_RELRO;
6286 if (decl && DECL_P (decl) && DECL_COMDAT_GROUP (decl))
6287 flags |= SECTION_LINKONCE;
6289 if (strcmp (name, ".vtable_map_vars") == 0)
6290 flags |= SECTION_LINKONCE;
6292 if (decl && VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6293 flags |= SECTION_TLS | SECTION_WRITE;
6295 if (strcmp (name, ".bss") == 0
6296 || strncmp (name, ".bss.", 5) == 0
6297 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6298 || strcmp (name, ".persistent.bss") == 0
6299 || strcmp (name, ".sbss") == 0
6300 || strncmp (name, ".sbss.", 6) == 0
6301 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6302 flags |= SECTION_BSS;
6304 if (strcmp (name, ".tdata") == 0
6305 || strncmp (name, ".tdata.", 7) == 0
6306 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6307 flags |= SECTION_TLS;
6309 if (strcmp (name, ".tbss") == 0
6310 || strncmp (name, ".tbss.", 6) == 0
6311 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6312 flags |= SECTION_TLS | SECTION_BSS;
6314 /* These three sections have special ELF types. They are neither
6315 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
6316 want to print a section type (@progbits or @nobits). If someone
6317 is silly enough to emit code or TLS variables to one of these
6318 sections, then don't handle them specially. */
6319 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6320 && (strcmp (name, ".init_array") == 0
6321 || strcmp (name, ".fini_array") == 0
6322 || strcmp (name, ".preinit_array") == 0))
6323 flags |= SECTION_NOTYPE;
6325 return flags;
6328 /* Return true if the target supports some form of global BSS,
6329 either through bss_noswitch_section, or by selecting a BSS
6330 section in TARGET_ASM_SELECT_SECTION. */
6332 bool
6333 have_global_bss_p (void)
6335 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6338 /* Output assembly to switch to section NAME with attribute FLAGS.
6339 Four variants for common object file formats. */
6341 void
6342 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6343 unsigned int flags ATTRIBUTE_UNUSED,
6344 tree decl ATTRIBUTE_UNUSED)
6346 /* Some object formats don't support named sections at all. The
6347 front-end should already have flagged this as an error. */
6348 gcc_unreachable ();
6351 #ifndef TLS_SECTION_ASM_FLAG
6352 #define TLS_SECTION_ASM_FLAG 'T'
6353 #endif
6355 void
6356 default_elf_asm_named_section (const char *name, unsigned int flags,
6357 tree decl)
6359 char flagchars[11], *f = flagchars;
6360 unsigned int numeric_value = 0;
6362 /* If we have already declared this section, we can use an
6363 abbreviated form to switch back to it -- unless this section is
6364 part of a COMDAT groups, in which case GAS requires the full
6365 declaration every time. */
6366 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6367 && (flags & SECTION_DECLARED))
6369 fprintf (asm_out_file, "\t.section\t%s\n", name);
6370 return;
6373 /* If we have a machine specific flag, then use the numeric value to pass
6374 this on to GAS. */
6375 if (targetm.asm_out.elf_flags_numeric (flags, &numeric_value))
6376 snprintf (f, sizeof (flagchars), "0x%08x", numeric_value);
6377 else
6379 if (!(flags & SECTION_DEBUG))
6380 *f++ = 'a';
6381 #if defined (HAVE_GAS_SECTION_EXCLUDE) && HAVE_GAS_SECTION_EXCLUDE == 1
6382 if (flags & SECTION_EXCLUDE)
6383 *f++ = 'e';
6384 #endif
6385 if (flags & SECTION_WRITE)
6386 *f++ = 'w';
6387 if (flags & SECTION_CODE)
6388 *f++ = 'x';
6389 if (flags & SECTION_SMALL)
6390 *f++ = 's';
6391 if (flags & SECTION_MERGE)
6392 *f++ = 'M';
6393 if (flags & SECTION_STRINGS)
6394 *f++ = 'S';
6395 if (flags & SECTION_TLS)
6396 *f++ = TLS_SECTION_ASM_FLAG;
6397 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6398 *f++ = 'G';
6399 #ifdef MACH_DEP_SECTION_ASM_FLAG
6400 if (flags & SECTION_MACH_DEP)
6401 *f++ = MACH_DEP_SECTION_ASM_FLAG;
6402 #endif
6403 *f = '\0';
6406 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6408 if (!(flags & SECTION_NOTYPE))
6410 const char *type;
6411 const char *format;
6413 if (flags & SECTION_BSS)
6414 type = "nobits";
6415 else
6416 type = "progbits";
6418 format = ",@%s";
6419 /* On platforms that use "@" as the assembly comment character,
6420 use "%" instead. */
6421 if (strcmp (ASM_COMMENT_START, "@") == 0)
6422 format = ",%%%s";
6423 fprintf (asm_out_file, format, type);
6425 if (flags & SECTION_ENTSIZE)
6426 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6427 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6429 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6430 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6431 else
6432 fprintf (asm_out_file, ",%s,comdat",
6433 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6437 putc ('\n', asm_out_file);
6440 void
6441 default_coff_asm_named_section (const char *name, unsigned int flags,
6442 tree decl ATTRIBUTE_UNUSED)
6444 char flagchars[8], *f = flagchars;
6446 if (flags & SECTION_WRITE)
6447 *f++ = 'w';
6448 if (flags & SECTION_CODE)
6449 *f++ = 'x';
6450 *f = '\0';
6452 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6455 void
6456 default_pe_asm_named_section (const char *name, unsigned int flags,
6457 tree decl)
6459 default_coff_asm_named_section (name, flags, decl);
6461 if (flags & SECTION_LINKONCE)
6463 /* Functions may have been compiled at various levels of
6464 optimization so we can't use `same_size' here.
6465 Instead, have the linker pick one. */
6466 fprintf (asm_out_file, "\t.linkonce %s\n",
6467 (flags & SECTION_CODE ? "discard" : "same_size"));
6471 /* The lame default section selector. */
6473 section *
6474 default_select_section (tree decl, int reloc,
6475 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6477 if (DECL_P (decl))
6479 if (decl_readonly_section (decl, reloc))
6480 return readonly_data_section;
6482 else if (TREE_CODE (decl) == CONSTRUCTOR)
6484 if (! ((flag_pic && reloc)
6485 || !TREE_READONLY (decl)
6486 || TREE_SIDE_EFFECTS (decl)
6487 || !TREE_CONSTANT (decl)))
6488 return readonly_data_section;
6490 else if (TREE_CODE (decl) == STRING_CST)
6491 return readonly_data_section;
6492 else if (! (flag_pic && reloc))
6493 return readonly_data_section;
6495 return data_section;
6498 enum section_category
6499 categorize_decl_for_section (const_tree decl, int reloc)
6501 enum section_category ret;
6503 if (TREE_CODE (decl) == FUNCTION_DECL)
6504 return SECCAT_TEXT;
6505 else if (TREE_CODE (decl) == STRING_CST)
6507 if ((flag_sanitize & SANITIZE_ADDRESS)
6508 && asan_protect_global (CONST_CAST_TREE (decl)))
6509 /* or !flag_merge_constants */
6510 return SECCAT_RODATA;
6511 else
6512 return SECCAT_RODATA_MERGE_STR;
6514 else if (VAR_P (decl))
6516 if (bss_initializer_p (decl))
6517 ret = SECCAT_BSS;
6518 else if (! TREE_READONLY (decl)
6519 || TREE_SIDE_EFFECTS (decl)
6520 || (DECL_INITIAL (decl)
6521 && ! TREE_CONSTANT (DECL_INITIAL (decl))))
6523 /* Here the reloc_rw_mask is not testing whether the section should
6524 be read-only or not, but whether the dynamic link will have to
6525 do something. If so, we wish to segregate the data in order to
6526 minimize cache misses inside the dynamic linker. */
6527 if (reloc & targetm.asm_out.reloc_rw_mask ())
6528 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6529 else
6530 ret = SECCAT_DATA;
6532 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6533 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6534 else if (reloc || flag_merge_constants < 2
6535 || ((flag_sanitize & SANITIZE_ADDRESS)
6536 && asan_protect_global (CONST_CAST_TREE (decl))))
6537 /* C and C++ don't allow different variables to share the same
6538 location. -fmerge-all-constants allows even that (at the
6539 expense of not conforming). */
6540 ret = SECCAT_RODATA;
6541 else if (DECL_INITIAL (decl)
6542 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6543 ret = SECCAT_RODATA_MERGE_STR_INIT;
6544 else
6545 ret = SECCAT_RODATA_MERGE_CONST;
6547 else if (TREE_CODE (decl) == CONSTRUCTOR)
6549 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6550 || TREE_SIDE_EFFECTS (decl)
6551 || ! TREE_CONSTANT (decl))
6552 ret = SECCAT_DATA;
6553 else
6554 ret = SECCAT_RODATA;
6556 else
6557 ret = SECCAT_RODATA;
6559 /* There are no read-only thread-local sections. */
6560 if (VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6562 /* Note that this would be *just* SECCAT_BSS, except that there's
6563 no concept of a read-only thread-local-data section. */
6564 if (ret == SECCAT_BSS
6565 || (flag_zero_initialized_in_bss
6566 && initializer_zerop (DECL_INITIAL (decl))))
6567 ret = SECCAT_TBSS;
6568 else
6569 ret = SECCAT_TDATA;
6572 /* If the target uses small data sections, select it. */
6573 else if (targetm.in_small_data_p (decl))
6575 if (ret == SECCAT_BSS)
6576 ret = SECCAT_SBSS;
6577 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6578 ret = SECCAT_SRODATA;
6579 else
6580 ret = SECCAT_SDATA;
6583 return ret;
6586 static bool
6587 decl_readonly_section_1 (enum section_category category)
6589 switch (category)
6591 case SECCAT_RODATA:
6592 case SECCAT_RODATA_MERGE_STR:
6593 case SECCAT_RODATA_MERGE_STR_INIT:
6594 case SECCAT_RODATA_MERGE_CONST:
6595 case SECCAT_SRODATA:
6596 return true;
6597 default:
6598 return false;
6602 bool
6603 decl_readonly_section (const_tree decl, int reloc)
6605 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6608 /* Select a section based on the above categorization. */
6610 section *
6611 default_elf_select_section (tree decl, int reloc,
6612 unsigned HOST_WIDE_INT align)
6614 const char *sname;
6615 switch (categorize_decl_for_section (decl, reloc))
6617 case SECCAT_TEXT:
6618 /* We're not supposed to be called on FUNCTION_DECLs. */
6619 gcc_unreachable ();
6620 case SECCAT_RODATA:
6621 return readonly_data_section;
6622 case SECCAT_RODATA_MERGE_STR:
6623 return mergeable_string_section (decl, align, 0);
6624 case SECCAT_RODATA_MERGE_STR_INIT:
6625 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6626 case SECCAT_RODATA_MERGE_CONST:
6627 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6628 case SECCAT_SRODATA:
6629 sname = ".sdata2";
6630 break;
6631 case SECCAT_DATA:
6632 return data_section;
6633 case SECCAT_DATA_REL:
6634 sname = ".data.rel";
6635 break;
6636 case SECCAT_DATA_REL_LOCAL:
6637 sname = ".data.rel.local";
6638 break;
6639 case SECCAT_DATA_REL_RO:
6640 sname = ".data.rel.ro";
6641 break;
6642 case SECCAT_DATA_REL_RO_LOCAL:
6643 sname = ".data.rel.ro.local";
6644 break;
6645 case SECCAT_SDATA:
6646 sname = ".sdata";
6647 break;
6648 case SECCAT_TDATA:
6649 sname = ".tdata";
6650 break;
6651 case SECCAT_BSS:
6652 if (bss_section)
6653 return bss_section;
6654 sname = ".bss";
6655 break;
6656 case SECCAT_SBSS:
6657 sname = ".sbss";
6658 break;
6659 case SECCAT_TBSS:
6660 sname = ".tbss";
6661 break;
6662 default:
6663 gcc_unreachable ();
6666 return get_named_section (decl, sname, reloc);
6669 /* Construct a unique section name based on the decl name and the
6670 categorization performed above. */
6672 void
6673 default_unique_section (tree decl, int reloc)
6675 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6676 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6677 const char *prefix, *name, *linkonce;
6678 char *string;
6679 tree id;
6681 switch (categorize_decl_for_section (decl, reloc))
6683 case SECCAT_TEXT:
6684 prefix = one_only ? ".t" : ".text";
6685 break;
6686 case SECCAT_RODATA:
6687 case SECCAT_RODATA_MERGE_STR:
6688 case SECCAT_RODATA_MERGE_STR_INIT:
6689 case SECCAT_RODATA_MERGE_CONST:
6690 prefix = one_only ? ".r" : ".rodata";
6691 break;
6692 case SECCAT_SRODATA:
6693 prefix = one_only ? ".s2" : ".sdata2";
6694 break;
6695 case SECCAT_DATA:
6696 prefix = one_only ? ".d" : ".data";
6697 break;
6698 case SECCAT_DATA_REL:
6699 prefix = one_only ? ".d.rel" : ".data.rel";
6700 break;
6701 case SECCAT_DATA_REL_LOCAL:
6702 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6703 break;
6704 case SECCAT_DATA_REL_RO:
6705 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6706 break;
6707 case SECCAT_DATA_REL_RO_LOCAL:
6708 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6709 break;
6710 case SECCAT_SDATA:
6711 prefix = one_only ? ".s" : ".sdata";
6712 break;
6713 case SECCAT_BSS:
6714 prefix = one_only ? ".b" : ".bss";
6715 break;
6716 case SECCAT_SBSS:
6717 prefix = one_only ? ".sb" : ".sbss";
6718 break;
6719 case SECCAT_TDATA:
6720 prefix = one_only ? ".td" : ".tdata";
6721 break;
6722 case SECCAT_TBSS:
6723 prefix = one_only ? ".tb" : ".tbss";
6724 break;
6725 default:
6726 gcc_unreachable ();
6729 id = DECL_ASSEMBLER_NAME (decl);
6730 ultimate_transparent_alias_target (&id);
6731 name = IDENTIFIER_POINTER (id);
6732 name = targetm.strip_name_encoding (name);
6734 /* If we're using one_only, then there needs to be a .gnu.linkonce
6735 prefix to the section name. */
6736 linkonce = one_only ? ".gnu.linkonce" : "";
6738 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6740 set_decl_section_name (decl, string);
6743 /* Subroutine of compute_reloc_for_rtx for leaf rtxes. */
6745 static int
6746 compute_reloc_for_rtx_1 (const_rtx x)
6748 switch (GET_CODE (x))
6750 case SYMBOL_REF:
6751 return SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6752 case LABEL_REF:
6753 return 1;
6754 default:
6755 return 0;
6759 /* Like compute_reloc_for_constant, except for an RTX. The return value
6760 is a mask for which bit 1 indicates a global relocation, and bit 0
6761 indicates a local relocation. */
6763 static int
6764 compute_reloc_for_rtx (const_rtx x)
6766 switch (GET_CODE (x))
6768 case SYMBOL_REF:
6769 case LABEL_REF:
6770 return compute_reloc_for_rtx_1 (x);
6772 case CONST:
6774 int reloc = 0;
6775 subrtx_iterator::array_type array;
6776 FOR_EACH_SUBRTX (iter, array, x, ALL)
6777 reloc |= compute_reloc_for_rtx_1 (*iter);
6778 return reloc;
6781 default:
6782 return 0;
6786 section *
6787 default_select_rtx_section (machine_mode mode ATTRIBUTE_UNUSED,
6788 rtx x,
6789 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6791 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6792 return data_section;
6793 else
6794 return readonly_data_section;
6797 section *
6798 default_elf_select_rtx_section (machine_mode mode, rtx x,
6799 unsigned HOST_WIDE_INT align)
6801 int reloc = compute_reloc_for_rtx (x);
6803 /* ??? Handle small data here somehow. */
6805 if (reloc & targetm.asm_out.reloc_rw_mask ())
6807 if (reloc == 1)
6808 return get_named_section (NULL, ".data.rel.ro.local", 1);
6809 else
6810 return get_named_section (NULL, ".data.rel.ro", 3);
6813 return mergeable_constant_section (mode, align, 0);
6816 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6818 void
6819 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6821 rtx symbol;
6822 int flags;
6824 /* Careful not to prod global register variables. */
6825 if (!MEM_P (rtl))
6826 return;
6827 symbol = XEXP (rtl, 0);
6828 if (GET_CODE (symbol) != SYMBOL_REF)
6829 return;
6831 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6832 if (TREE_CODE (decl) == FUNCTION_DECL)
6833 flags |= SYMBOL_FLAG_FUNCTION;
6834 if (targetm.binds_local_p (decl))
6835 flags |= SYMBOL_FLAG_LOCAL;
6836 if (VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6837 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6838 else if (targetm.in_small_data_p (decl))
6839 flags |= SYMBOL_FLAG_SMALL;
6840 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6841 being PUBLIC, the thing *must* be defined in this translation unit.
6842 Prevent this buglet from being propagated into rtl code as well. */
6843 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6844 flags |= SYMBOL_FLAG_EXTERNAL;
6846 SYMBOL_REF_FLAGS (symbol) = flags;
6849 /* By default, we do nothing for encode_section_info, so we need not
6850 do anything but discard the '*' marker. */
6852 const char *
6853 default_strip_name_encoding (const char *str)
6855 return str + (*str == '*');
6858 #ifdef ASM_OUTPUT_DEF
6859 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6860 anchor relative to ".", the current section position. */
6862 void
6863 default_asm_output_anchor (rtx symbol)
6865 char buffer[100];
6867 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6868 SYMBOL_REF_BLOCK_OFFSET (symbol));
6869 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6871 #endif
6873 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6875 bool
6876 default_use_anchors_for_symbol_p (const_rtx symbol)
6878 section *sect;
6879 tree decl;
6881 /* Don't use anchors for mergeable sections. The linker might move
6882 the objects around. */
6883 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6884 if (sect->common.flags & SECTION_MERGE)
6885 return false;
6887 /* Don't use anchors for small data sections. The small data register
6888 acts as an anchor for such sections. */
6889 if (sect->common.flags & SECTION_SMALL)
6890 return false;
6892 decl = SYMBOL_REF_DECL (symbol);
6893 if (decl && DECL_P (decl))
6895 /* Don't use section anchors for decls that might be defined or
6896 usurped by other modules. */
6897 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6898 return false;
6900 /* Don't use section anchors for decls that will be placed in a
6901 small data section. */
6902 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6903 one above. The problem is that we only use SECTION_SMALL for
6904 sections that should be marked as small in the section directive. */
6905 if (targetm.in_small_data_p (decl))
6906 return false;
6908 /* Don't use section anchors for decls that won't fit inside a single
6909 anchor range to reduce the amount of instructions required to refer
6910 to the entire declaration. */
6911 if (DECL_SIZE_UNIT (decl) == NULL_TREE
6912 || !tree_fits_uhwi_p (DECL_SIZE_UNIT (decl))
6913 || (tree_to_uhwi (DECL_SIZE_UNIT (decl))
6914 >= (unsigned HOST_WIDE_INT) targetm.max_anchor_offset))
6915 return false;
6918 return true;
6921 /* Return true when RESOLUTION indicate that symbol will be bound to the
6922 definition provided by current .o file. */
6924 static bool
6925 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
6927 return (resolution == LDPR_PREVAILING_DEF
6928 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6929 || resolution == LDPR_PREVAILING_DEF_IRONLY);
6932 /* Return true when RESOLUTION indicate that symbol will be bound locally
6933 within current executable or DSO. */
6935 static bool
6936 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
6938 return (resolution == LDPR_PREVAILING_DEF
6939 || resolution == LDPR_PREVAILING_DEF_IRONLY
6940 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6941 || resolution == LDPR_PREEMPTED_REG
6942 || resolution == LDPR_PREEMPTED_IR
6943 || resolution == LDPR_RESOLVED_IR
6944 || resolution == LDPR_RESOLVED_EXEC);
6947 /* COMMON_LOCAL_P is true means that the linker can guarantee that an
6948 uninitialized common symbol in the executable will still be defined
6949 (through COPY relocation) in the executable. */
6951 bool
6952 default_binds_local_p_3 (const_tree exp, bool shlib, bool weak_dominate,
6953 bool extern_protected_data, bool common_local_p)
6955 /* A non-decl is an entry in the constant pool. */
6956 if (!DECL_P (exp))
6957 return true;
6959 /* Weakrefs may not bind locally, even though the weakref itself is always
6960 static and therefore local. Similarly, the resolver for ifunc functions
6961 might resolve to a non-local function.
6962 FIXME: We can resolve the weakref case more curefuly by looking at the
6963 weakref alias. */
6964 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
6965 || (TREE_CODE (exp) == FUNCTION_DECL
6966 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
6967 return false;
6969 /* Static variables are always local. */
6970 if (! TREE_PUBLIC (exp))
6971 return true;
6973 /* With resolution file in hand, take look into resolutions.
6974 We can't just return true for resolved_locally symbols,
6975 because dynamic linking might overwrite symbols
6976 in shared libraries. */
6977 bool resolved_locally = false;
6979 bool uninited_common = (DECL_COMMON (exp)
6980 && (DECL_INITIAL (exp) == NULL
6981 || (!in_lto_p
6982 && DECL_INITIAL (exp) == error_mark_node)));
6984 /* A non-external variable is defined locally only if it isn't
6985 uninitialized COMMON variable or common_local_p is true. */
6986 bool defined_locally = (!DECL_EXTERNAL (exp)
6987 && (!uninited_common || common_local_p));
6988 if (symtab_node *node = symtab_node::get (exp))
6990 if (node->in_other_partition)
6991 defined_locally = true;
6992 if (node->can_be_discarded_p ())
6994 else if (resolution_to_local_definition_p (node->resolution))
6995 defined_locally = resolved_locally = true;
6996 else if (resolution_local_p (node->resolution))
6997 resolved_locally = true;
6999 if (defined_locally && weak_dominate && !shlib)
7000 resolved_locally = true;
7002 /* Undefined weak symbols are never defined locally. */
7003 if (DECL_WEAK (exp) && !defined_locally)
7004 return false;
7006 /* A symbol is local if the user has said explicitly that it will be,
7007 or if we have a definition for the symbol. We cannot infer visibility
7008 for undefined symbols. */
7009 if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT
7010 && (TREE_CODE (exp) == FUNCTION_DECL
7011 || !extern_protected_data
7012 || DECL_VISIBILITY (exp) != VISIBILITY_PROTECTED)
7013 && (DECL_VISIBILITY_SPECIFIED (exp) || defined_locally))
7014 return true;
7016 /* If PIC, then assume that any global name can be overridden by
7017 symbols resolved from other modules. */
7018 if (shlib)
7019 return false;
7021 /* Variables defined outside this object might not be local. */
7022 if (DECL_EXTERNAL (exp) && !resolved_locally)
7023 return false;
7025 /* Non-dominant weak symbols are not defined locally. */
7026 if (DECL_WEAK (exp) && !resolved_locally)
7027 return false;
7029 /* Uninitialized COMMON variable may be unified with symbols
7030 resolved from other modules. */
7031 if (uninited_common && !resolved_locally)
7032 return false;
7034 /* Otherwise we're left with initialized (or non-common) global data
7035 which is of necessity defined locally. */
7036 return true;
7039 /* Assume ELF-ish defaults, since that's pretty much the most liberal
7040 wrt cross-module name binding. */
7042 bool
7043 default_binds_local_p (const_tree exp)
7045 return default_binds_local_p_3 (exp, flag_shlib != 0, true, false, false);
7048 /* Similar to default_binds_local_p, but common symbol may be local and
7049 extern protected data is non-local. */
7051 bool
7052 default_binds_local_p_2 (const_tree exp)
7054 return default_binds_local_p_3 (exp, flag_shlib != 0, true, true,
7055 !flag_pic);
7058 bool
7059 default_binds_local_p_1 (const_tree exp, int shlib)
7061 return default_binds_local_p_3 (exp, shlib != 0, false, false, false);
7064 /* Return true when references to DECL must bind to current definition in
7065 final executable.
7067 The condition is usually equivalent to whether the function binds to the
7068 current module (shared library or executable), that is to binds_local_p.
7069 We use this fact to avoid need for another target hook and implement
7070 the logic using binds_local_p and just special cases where
7071 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
7072 the weak definitions (that can be overwritten at linktime by other
7073 definition from different object file) and when resolution info is available
7074 we simply use the knowledge passed to us by linker plugin. */
7075 bool
7076 decl_binds_to_current_def_p (const_tree decl)
7078 gcc_assert (DECL_P (decl));
7079 if (!targetm.binds_local_p (decl))
7080 return false;
7081 if (!TREE_PUBLIC (decl))
7082 return true;
7084 /* When resolution is available, just use it. */
7085 if (symtab_node *node = symtab_node::get (decl))
7087 if (node->resolution != LDPR_UNKNOWN
7088 && !node->can_be_discarded_p ())
7089 return resolution_to_local_definition_p (node->resolution);
7092 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
7093 binds locally but still can be overwritten), DECL_COMMON (can be merged
7094 with a non-common definition somewhere in the same module) or
7095 DECL_EXTERNAL.
7096 This rely on fact that binds_local_p behave as decl_replaceable_p
7097 for all other declaration types. */
7098 if (DECL_WEAK (decl))
7099 return false;
7100 if (DECL_COMMON (decl)
7101 && (DECL_INITIAL (decl) == NULL
7102 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
7103 return false;
7104 if (DECL_EXTERNAL (decl))
7105 return false;
7106 return true;
7109 /* A replaceable function or variable is one which may be replaced
7110 at link-time with an entirely different definition, provided that the
7111 replacement has the same type. For example, functions declared
7112 with __attribute__((weak)) on most systems are replaceable.
7114 COMDAT functions are not replaceable, since all definitions of the
7115 function must be equivalent. It is important that COMDAT functions
7116 not be treated as replaceable so that use of C++ template
7117 instantiations is not penalized. */
7119 bool
7120 decl_replaceable_p (tree decl)
7122 gcc_assert (DECL_P (decl));
7123 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
7124 return false;
7125 if (!flag_semantic_interposition
7126 && !DECL_WEAK (decl))
7127 return false;
7128 return !decl_binds_to_current_def_p (decl);
7131 /* Default function to output code that will globalize a label. A
7132 target must define GLOBAL_ASM_OP or provide its own function to
7133 globalize a label. */
7134 #ifdef GLOBAL_ASM_OP
7135 void
7136 default_globalize_label (FILE * stream, const char *name)
7138 fputs (GLOBAL_ASM_OP, stream);
7139 assemble_name (stream, name);
7140 putc ('\n', stream);
7142 #endif /* GLOBAL_ASM_OP */
7144 /* Default function to output code that will globalize a declaration. */
7145 void
7146 default_globalize_decl_name (FILE * stream, tree decl)
7148 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
7149 targetm.asm_out.globalize_label (stream, name);
7152 /* Default function to output a label for unwind information. The
7153 default is to do nothing. A target that needs nonlocal labels for
7154 unwind information must provide its own function to do this. */
7155 void
7156 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
7157 tree decl ATTRIBUTE_UNUSED,
7158 int for_eh ATTRIBUTE_UNUSED,
7159 int empty ATTRIBUTE_UNUSED)
7163 /* Default function to output a label to divide up the exception table.
7164 The default is to do nothing. A target that needs/wants to divide
7165 up the table must provide it's own function to do this. */
7166 void
7167 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
7171 /* This is how to output an internal numbered label where PREFIX is
7172 the class of label and LABELNO is the number within the class. */
7174 void
7175 default_generate_internal_label (char *buf, const char *prefix,
7176 unsigned long labelno)
7178 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
7181 /* This is how to output an internal numbered label where PREFIX is
7182 the class of label and LABELNO is the number within the class. */
7184 void
7185 default_internal_label (FILE *stream, const char *prefix,
7186 unsigned long labelno)
7188 char *const buf = (char *) alloca (40 + strlen (prefix));
7189 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
7190 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
7194 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
7196 void
7197 default_asm_declare_constant_name (FILE *file, const char *name,
7198 const_tree exp ATTRIBUTE_UNUSED,
7199 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
7201 assemble_label (file, name);
7204 /* This is the default behavior at the beginning of a file. It's
7205 controlled by two other target-hook toggles. */
7206 void
7207 default_file_start (void)
7209 if (targetm.asm_file_start_app_off
7210 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
7211 fputs (ASM_APP_OFF, asm_out_file);
7213 if (targetm.asm_file_start_file_directive)
7215 /* LTO produced units have no meaningful main_input_filename. */
7216 if (in_lto_p)
7217 output_file_directive (asm_out_file, "<artificial>");
7218 else
7219 output_file_directive (asm_out_file, main_input_filename);
7223 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
7224 which emits a special section directive used to indicate whether or
7225 not this object file needs an executable stack. This is primarily
7226 a GNU extension to ELF but could be used on other targets. */
7228 int trampolines_created;
7230 void
7231 file_end_indicate_exec_stack (void)
7233 unsigned int flags = SECTION_DEBUG;
7234 if (trampolines_created)
7235 flags |= SECTION_CODE;
7237 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
7240 /* Emit a special section directive to indicate that this object file
7241 was compiled with -fsplit-stack. This is used to let the linker
7242 detect calls between split-stack code and non-split-stack code, so
7243 that it can modify the split-stack code to allocate a sufficiently
7244 large stack. We emit another special section if there are any
7245 functions in this file which have the no_split_stack attribute, to
7246 prevent the linker from warning about being unable to convert the
7247 functions if they call non-split-stack code. */
7249 void
7250 file_end_indicate_split_stack (void)
7252 if (flag_split_stack)
7254 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
7255 NULL));
7256 if (saw_no_split_stack)
7257 switch_to_section (get_section (".note.GNU-no-split-stack",
7258 SECTION_DEBUG, NULL));
7262 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
7263 a get_unnamed_section callback. */
7265 void
7266 output_section_asm_op (const void *directive)
7268 fprintf (asm_out_file, "%s\n", (const char *) directive);
7271 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
7272 the current section is NEW_SECTION. */
7274 void
7275 switch_to_section (section *new_section)
7277 if (in_section == new_section)
7278 return;
7280 if (new_section->common.flags & SECTION_FORGET)
7281 in_section = NULL;
7282 else
7283 in_section = new_section;
7285 switch (SECTION_STYLE (new_section))
7287 case SECTION_NAMED:
7288 targetm.asm_out.named_section (new_section->named.name,
7289 new_section->named.common.flags,
7290 new_section->named.decl);
7291 break;
7293 case SECTION_UNNAMED:
7294 new_section->unnamed.callback (new_section->unnamed.data);
7295 break;
7297 case SECTION_NOSWITCH:
7298 gcc_unreachable ();
7299 break;
7302 new_section->common.flags |= SECTION_DECLARED;
7305 /* If block symbol SYMBOL has not yet been assigned an offset, place
7306 it at the end of its block. */
7308 void
7309 place_block_symbol (rtx symbol)
7311 unsigned HOST_WIDE_INT size, mask, offset;
7312 struct constant_descriptor_rtx *desc;
7313 unsigned int alignment;
7314 struct object_block *block;
7315 tree decl;
7317 gcc_assert (SYMBOL_REF_BLOCK (symbol));
7318 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7319 return;
7321 /* Work out the symbol's size and alignment. */
7322 if (CONSTANT_POOL_ADDRESS_P (symbol))
7324 desc = SYMBOL_REF_CONSTANT (symbol);
7325 alignment = desc->align;
7326 size = GET_MODE_SIZE (desc->mode);
7328 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7330 decl = SYMBOL_REF_DECL (symbol);
7331 gcc_checking_assert (DECL_IN_CONSTANT_POOL (decl));
7332 alignment = DECL_ALIGN (decl);
7333 size = get_constant_size (DECL_INITIAL (decl));
7334 if ((flag_sanitize & SANITIZE_ADDRESS)
7335 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7336 && asan_protect_global (DECL_INITIAL (decl)))
7338 size += asan_red_zone_size (size);
7339 alignment = MAX (alignment,
7340 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7343 else
7345 struct symtab_node *snode;
7346 decl = SYMBOL_REF_DECL (symbol);
7348 snode = symtab_node::get (decl);
7349 if (snode->alias)
7351 rtx target = DECL_RTL (snode->ultimate_alias_target ()->decl);
7353 gcc_assert (MEM_P (target)
7354 && GET_CODE (XEXP (target, 0)) == SYMBOL_REF
7355 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (target, 0)));
7356 target = XEXP (target, 0);
7357 place_block_symbol (target);
7358 SYMBOL_REF_BLOCK_OFFSET (symbol) = SYMBOL_REF_BLOCK_OFFSET (target);
7359 return;
7361 alignment = get_variable_align (decl);
7362 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7363 if ((flag_sanitize & SANITIZE_ADDRESS)
7364 && asan_protect_global (decl))
7366 size += asan_red_zone_size (size);
7367 alignment = MAX (alignment,
7368 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7372 /* Calculate the object's offset from the start of the block. */
7373 block = SYMBOL_REF_BLOCK (symbol);
7374 mask = alignment / BITS_PER_UNIT - 1;
7375 offset = (block->size + mask) & ~mask;
7376 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7378 /* Record the block's new alignment and size. */
7379 block->alignment = MAX (block->alignment, alignment);
7380 block->size = offset + size;
7382 vec_safe_push (block->objects, symbol);
7385 /* Return the anchor that should be used to address byte offset OFFSET
7386 from the first object in BLOCK. MODEL is the TLS model used
7387 to access it. */
7390 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7391 enum tls_model model)
7393 char label[100];
7394 unsigned int begin, middle, end;
7395 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7396 rtx anchor;
7398 /* Work out the anchor's offset. Use an offset of 0 for the first
7399 anchor so that we don't pessimize the case where we take the address
7400 of a variable at the beginning of the block. This is particularly
7401 useful when a block has only one variable assigned to it.
7403 We try to place anchors RANGE bytes apart, so there can then be
7404 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7405 a ptr_mode offset. With some target settings, the lowest such
7406 anchor might be out of range for the lowest ptr_mode offset;
7407 likewise the highest anchor for the highest offset. Use anchors
7408 at the extreme ends of the ptr_mode range in such cases.
7410 All arithmetic uses unsigned integers in order to avoid
7411 signed overflow. */
7412 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7413 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7414 range = max_offset - min_offset + 1;
7415 if (range == 0)
7416 offset = 0;
7417 else
7419 bias = HOST_WIDE_INT_1U << (GET_MODE_BITSIZE (ptr_mode) - 1);
7420 if (offset < 0)
7422 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7423 delta -= delta % range;
7424 if (delta > bias)
7425 delta = bias;
7426 offset = (HOST_WIDE_INT) (-delta);
7428 else
7430 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7431 delta -= delta % range;
7432 if (delta > bias - 1)
7433 delta = bias - 1;
7434 offset = (HOST_WIDE_INT) delta;
7438 /* Do a binary search to see if there's already an anchor we can use.
7439 Set BEGIN to the new anchor's index if not. */
7440 begin = 0;
7441 end = vec_safe_length (block->anchors);
7442 while (begin != end)
7444 middle = (end + begin) / 2;
7445 anchor = (*block->anchors)[middle];
7446 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7447 end = middle;
7448 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7449 begin = middle + 1;
7450 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7451 end = middle;
7452 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7453 begin = middle + 1;
7454 else
7455 return anchor;
7458 /* Create a new anchor with a unique label. */
7459 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7460 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7461 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7462 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7464 /* Insert it at index BEGIN. */
7465 vec_safe_insert (block->anchors, begin, anchor);
7466 return anchor;
7469 /* Output the objects in BLOCK. */
7471 static void
7472 output_object_block (struct object_block *block)
7474 struct constant_descriptor_rtx *desc;
7475 unsigned int i;
7476 HOST_WIDE_INT offset;
7477 tree decl;
7478 rtx symbol;
7480 if (!block->objects)
7481 return;
7483 /* Switch to the section and make sure that the first byte is
7484 suitably aligned. */
7485 /* Special case VTV comdat sections similar to assemble_variable. */
7486 if (SECTION_STYLE (block->sect) == SECTION_NAMED
7487 && block->sect->named.name
7488 && (strcmp (block->sect->named.name, ".vtable_map_vars") == 0))
7489 handle_vtv_comdat_section (block->sect, block->sect->named.decl);
7490 else
7491 switch_to_section (block->sect);
7493 assemble_align (block->alignment);
7495 /* Define the values of all anchors relative to the current section
7496 position. */
7497 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7498 targetm.asm_out.output_anchor (symbol);
7500 /* Output the objects themselves. */
7501 offset = 0;
7502 FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7504 /* Move to the object's offset, padding with zeros if necessary. */
7505 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7506 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7507 if (CONSTANT_POOL_ADDRESS_P (symbol))
7509 desc = SYMBOL_REF_CONSTANT (symbol);
7510 /* Pass 1 for align as we have already laid out everything in the block.
7511 So aligning shouldn't be necessary. */
7512 output_constant_pool_1 (desc, 1);
7513 offset += GET_MODE_SIZE (desc->mode);
7515 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7517 HOST_WIDE_INT size;
7518 decl = SYMBOL_REF_DECL (symbol);
7519 assemble_constant_contents
7520 (DECL_INITIAL (decl), XSTR (symbol, 0), DECL_ALIGN (decl));
7522 size = get_constant_size (DECL_INITIAL (decl));
7523 offset += size;
7524 if ((flag_sanitize & SANITIZE_ADDRESS)
7525 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7526 && asan_protect_global (DECL_INITIAL (decl)))
7528 size = asan_red_zone_size (size);
7529 assemble_zeros (size);
7530 offset += size;
7533 else
7535 HOST_WIDE_INT size;
7536 decl = SYMBOL_REF_DECL (symbol);
7537 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7538 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7539 offset += size;
7540 if ((flag_sanitize & SANITIZE_ADDRESS)
7541 && asan_protect_global (decl))
7543 size = asan_red_zone_size (size);
7544 assemble_zeros (size);
7545 offset += size;
7551 /* A callback for qsort to compare object_blocks. */
7553 static int
7554 output_object_block_compare (const void *x, const void *y)
7556 object_block *p1 = *(object_block * const*)x;
7557 object_block *p2 = *(object_block * const*)y;
7559 if (p1->sect->common.flags & SECTION_NAMED
7560 && !(p2->sect->common.flags & SECTION_NAMED))
7561 return 1;
7563 if (!(p1->sect->common.flags & SECTION_NAMED)
7564 && p2->sect->common.flags & SECTION_NAMED)
7565 return -1;
7567 if (p1->sect->common.flags & SECTION_NAMED
7568 && p2->sect->common.flags & SECTION_NAMED)
7569 return strcmp (p1->sect->named.name, p2->sect->named.name);
7571 unsigned f1 = p1->sect->common.flags;
7572 unsigned f2 = p2->sect->common.flags;
7573 if (f1 == f2)
7574 return 0;
7575 return f1 < f2 ? -1 : 1;
7578 /* Output the definitions of all object_blocks. */
7580 void
7581 output_object_blocks (void)
7583 vec<object_block *, va_heap> v;
7584 v.create (object_block_htab->elements ());
7585 object_block *obj;
7586 hash_table<object_block_hasher>::iterator hi;
7588 FOR_EACH_HASH_TABLE_ELEMENT (*object_block_htab, obj, object_block *, hi)
7589 v.quick_push (obj);
7591 /* Sort them in order to output them in a deterministic manner,
7592 otherwise we may get .rodata sections in different orders with
7593 and without -g. */
7594 v.qsort (output_object_block_compare);
7595 unsigned i;
7596 FOR_EACH_VEC_ELT (v, i, obj)
7597 output_object_block (obj);
7599 v.release ();
7602 /* This function provides a possible implementation of the
7603 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7604 by -frecord-gcc-switches it creates a new mergeable, string section in the
7605 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7606 contains the switches in ASCII format.
7608 FIXME: This code does not correctly handle double quote characters
7609 that appear inside strings, (it strips them rather than preserving them).
7610 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7611 characters - instead it treats them as sub-string separators. Since
7612 we want to emit NUL strings terminators into the object file we have to use
7613 ASM_OUTPUT_SKIP. */
7616 elf_record_gcc_switches (print_switch_type type, const char * name)
7618 switch (type)
7620 case SWITCH_TYPE_PASSED:
7621 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7622 ASM_OUTPUT_SKIP (asm_out_file, HOST_WIDE_INT_1U);
7623 break;
7625 case SWITCH_TYPE_DESCRIPTIVE:
7626 if (name == NULL)
7628 /* Distinguish between invocations where name is NULL. */
7629 static bool started = false;
7631 if (!started)
7633 section * sec;
7635 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7636 SECTION_DEBUG
7637 | SECTION_MERGE
7638 | SECTION_STRINGS
7639 | (SECTION_ENTSIZE & 1),
7640 NULL);
7641 switch_to_section (sec);
7642 started = true;
7646 default:
7647 break;
7650 /* The return value is currently ignored by the caller, but must be 0.
7651 For -fverbose-asm the return value would be the number of characters
7652 emitted into the assembler file. */
7653 return 0;
7656 /* Emit text to declare externally defined symbols. It is needed to
7657 properly support non-default visibility. */
7658 void
7659 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7660 tree decl,
7661 const char *name ATTRIBUTE_UNUSED)
7663 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7664 set in order to avoid putting out names that are never really
7665 used. Always output visibility specified in the source. */
7666 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7667 && (DECL_VISIBILITY_SPECIFIED (decl)
7668 || targetm.binds_local_p (decl)))
7669 maybe_assemble_visibility (decl);
7672 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7674 void
7675 default_asm_output_source_filename (FILE *file, const char *name)
7677 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7678 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7679 #else
7680 fprintf (file, "\t.file\t");
7681 output_quoted_string (file, name);
7682 putc ('\n', file);
7683 #endif
7686 /* Output a file name in the form wanted by System V. */
7688 void
7689 output_file_directive (FILE *asm_file, const char *input_name)
7691 int len;
7692 const char *na;
7694 if (input_name == NULL)
7695 input_name = "<stdin>";
7696 else
7697 input_name = remap_debug_filename (input_name);
7699 len = strlen (input_name);
7700 na = input_name + len;
7702 /* NA gets INPUT_NAME sans directory names. */
7703 while (na > input_name)
7705 if (IS_DIR_SEPARATOR (na[-1]))
7706 break;
7707 na--;
7710 targetm.asm_out.output_source_filename (asm_file, na);
7713 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7714 EXP. */
7716 make_debug_expr_from_rtl (const_rtx exp)
7718 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7719 machine_mode mode = GET_MODE (exp);
7720 rtx dval;
7722 DECL_ARTIFICIAL (ddecl) = 1;
7723 if (REG_P (exp) && REG_EXPR (exp))
7724 type = TREE_TYPE (REG_EXPR (exp));
7725 else if (MEM_P (exp) && MEM_EXPR (exp))
7726 type = TREE_TYPE (MEM_EXPR (exp));
7727 else
7728 type = NULL_TREE;
7729 if (type && TYPE_MODE (type) == mode)
7730 TREE_TYPE (ddecl) = type;
7731 else
7732 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7733 SET_DECL_MODE (ddecl, mode);
7734 dval = gen_rtx_DEBUG_EXPR (mode);
7735 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7736 SET_DECL_RTL (ddecl, dval);
7737 return dval;
7740 #ifdef ELF_ASCII_ESCAPES
7741 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7743 void
7744 default_elf_asm_output_limited_string (FILE *f, const char *s)
7746 int escape;
7747 unsigned char c;
7749 fputs (STRING_ASM_OP, f);
7750 putc ('"', f);
7751 while (*s != '\0')
7753 c = *s;
7754 escape = ELF_ASCII_ESCAPES[c];
7755 switch (escape)
7757 case 0:
7758 putc (c, f);
7759 break;
7760 case 1:
7761 putc ('\\', f);
7762 putc ('0'+((c>>6)&7), f);
7763 putc ('0'+((c>>3)&7), f);
7764 putc ('0'+(c&7), f);
7765 break;
7766 default:
7767 putc ('\\', f);
7768 putc (escape, f);
7769 break;
7771 s++;
7773 putc ('\"', f);
7774 putc ('\n', f);
7777 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7779 void
7780 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7782 const char *limit = s + len;
7783 const char *last_null = NULL;
7784 unsigned bytes_in_chunk = 0;
7785 unsigned char c;
7786 int escape;
7788 for (; s < limit; s++)
7790 const char *p;
7792 if (bytes_in_chunk >= 60)
7794 putc ('\"', f);
7795 putc ('\n', f);
7796 bytes_in_chunk = 0;
7799 if (s > last_null)
7801 for (p = s; p < limit && *p != '\0'; p++)
7802 continue;
7803 last_null = p;
7805 else
7806 p = last_null;
7808 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7810 if (bytes_in_chunk > 0)
7812 putc ('\"', f);
7813 putc ('\n', f);
7814 bytes_in_chunk = 0;
7817 default_elf_asm_output_limited_string (f, s);
7818 s = p;
7820 else
7822 if (bytes_in_chunk == 0)
7823 fputs (ASCII_DATA_ASM_OP "\"", f);
7825 c = *s;
7826 escape = ELF_ASCII_ESCAPES[c];
7827 switch (escape)
7829 case 0:
7830 putc (c, f);
7831 bytes_in_chunk++;
7832 break;
7833 case 1:
7834 putc ('\\', f);
7835 putc ('0'+((c>>6)&7), f);
7836 putc ('0'+((c>>3)&7), f);
7837 putc ('0'+(c&7), f);
7838 bytes_in_chunk += 4;
7839 break;
7840 default:
7841 putc ('\\', f);
7842 putc (escape, f);
7843 bytes_in_chunk += 2;
7844 break;
7850 if (bytes_in_chunk > 0)
7852 putc ('\"', f);
7853 putc ('\n', f);
7856 #endif
7858 static GTY(()) section *elf_init_array_section;
7859 static GTY(()) section *elf_fini_array_section;
7861 static section *
7862 get_elf_initfini_array_priority_section (int priority,
7863 bool constructor_p)
7865 section *sec;
7866 if (priority != DEFAULT_INIT_PRIORITY)
7868 char buf[18];
7869 sprintf (buf, "%s.%.5u",
7870 constructor_p ? ".init_array" : ".fini_array",
7871 priority);
7872 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7874 else
7876 if (constructor_p)
7878 if (elf_init_array_section == NULL)
7879 elf_init_array_section
7880 = get_section (".init_array",
7881 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7882 sec = elf_init_array_section;
7884 else
7886 if (elf_fini_array_section == NULL)
7887 elf_fini_array_section
7888 = get_section (".fini_array",
7889 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7890 sec = elf_fini_array_section;
7893 return sec;
7896 /* Use .init_array section for constructors. */
7898 void
7899 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7901 section *sec = get_elf_initfini_array_priority_section (priority,
7902 true);
7903 assemble_addr_to_section (symbol, sec);
7906 /* Use .fini_array section for destructors. */
7908 void
7909 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7911 section *sec = get_elf_initfini_array_priority_section (priority,
7912 false);
7913 assemble_addr_to_section (symbol, sec);
7916 /* Default TARGET_ASM_OUTPUT_IDENT hook.
7918 This is a bit of a cheat. The real default is a no-op, but this
7919 hook is the default for all targets with a .ident directive. */
7921 void
7922 default_asm_output_ident_directive (const char *ident_str)
7924 const char *ident_asm_op = "\t.ident\t";
7926 /* If we are still in the front end, do not write out the string
7927 to asm_out_file. Instead, add a fake top-level asm statement.
7928 This allows the front ends to use this hook without actually
7929 writing to asm_out_file, to handle #ident or Pragma Ident. */
7930 if (symtab->state == PARSING)
7932 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
7933 symtab->finalize_toplevel_asm (build_string (strlen (buf), buf));
7935 else
7936 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
7940 /* This function ensures that vtable_map variables are not only
7941 in the comdat section, but that each variable has its own unique
7942 comdat name. Without this the variables end up in the same section
7943 with a single comdat name.
7945 FIXME: resolve_unique_section needs to deal better with
7946 decls with both DECL_SECTION_NAME and DECL_ONE_ONLY. Once
7947 that is fixed, this if-else statement can be replaced with
7948 a single call to "switch_to_section (sect)". */
7950 static void
7951 handle_vtv_comdat_section (section *sect, const_tree decl ATTRIBUTE_UNUSED)
7953 #if defined (OBJECT_FORMAT_ELF)
7954 targetm.asm_out.named_section (sect->named.name,
7955 sect->named.common.flags
7956 | SECTION_LINKONCE,
7957 DECL_NAME (decl));
7958 in_section = sect;
7959 #else
7960 /* Neither OBJECT_FORMAT_PE, nor OBJECT_FORMAT_COFF is set here.
7961 Therefore the following check is used.
7962 In case a the target is PE or COFF a comdat group section
7963 is created, e.g. .vtable_map_vars$foo. The linker places
7964 everything in .vtable_map_vars at the end.
7966 A fix could be made in
7967 gcc/config/i386/winnt.c: i386_pe_unique_section. */
7968 if (TARGET_PECOFF)
7970 char *name;
7972 if (TREE_CODE (DECL_NAME (decl)) == IDENTIFIER_NODE)
7973 name = ACONCAT ((sect->named.name, "$",
7974 IDENTIFIER_POINTER (DECL_NAME (decl)), NULL));
7975 else
7976 name = ACONCAT ((sect->named.name, "$",
7977 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (DECL_NAME (decl))),
7978 NULL));
7980 targetm.asm_out.named_section (name,
7981 sect->named.common.flags
7982 | SECTION_LINKONCE,
7983 DECL_NAME (decl));
7984 in_section = sect;
7986 else
7987 switch_to_section (sect);
7988 #endif
7991 #include "gt-varasm.h"