re PR debug/81936 (ICE in dwarf2out_die_ref_for_decl, at dwarf2out.c:5543)
[official-gcc.git] / gcc / varasm.c
blob91680d692b4a29662ab0c2c76a3547e74c0fb0c2
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 machine_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 = 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 return (DECL_INITIAL (decl) == NULL
980 /* In LTO we have no errors in program; error_mark_node is used
981 to mark offlined constructors. */
982 || (DECL_INITIAL (decl) == error_mark_node
983 && !in_lto_p)
984 || (flag_zero_initialized_in_bss
985 /* Leave constant zeroes in .rodata so they
986 can be shared. */
987 && !TREE_READONLY (decl)
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 (!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);
2784 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0);
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, machine_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 default:
2928 gcc_unreachable ();
2931 gcc_assert (MEM_P (x));
2932 x = XEXP (x, 0);
2934 value->base = x;
2935 value->offset = offset;
2938 static GTY(()) hash_table<tree_descriptor_hasher> *const_desc_htab;
2940 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2942 /* Constant pool accessor function. */
2944 hash_table<tree_descriptor_hasher> *
2945 constant_pool_htab (void)
2947 return const_desc_htab;
2950 /* Compute a hash code for a constant expression. */
2952 hashval_t
2953 tree_descriptor_hasher::hash (constant_descriptor_tree *ptr)
2955 return ptr->hash;
2958 static hashval_t
2959 const_hash_1 (const tree exp)
2961 const char *p;
2962 hashval_t hi;
2963 int len, i;
2964 enum tree_code code = TREE_CODE (exp);
2966 /* Either set P and LEN to the address and len of something to hash and
2967 exit the switch or return a value. */
2969 switch (code)
2971 case INTEGER_CST:
2972 p = (char *) &TREE_INT_CST_ELT (exp, 0);
2973 len = TREE_INT_CST_NUNITS (exp) * sizeof (HOST_WIDE_INT);
2974 break;
2976 case REAL_CST:
2977 return real_hash (TREE_REAL_CST_PTR (exp));
2979 case FIXED_CST:
2980 return fixed_hash (TREE_FIXED_CST_PTR (exp));
2982 case STRING_CST:
2983 p = TREE_STRING_POINTER (exp);
2984 len = TREE_STRING_LENGTH (exp);
2985 break;
2987 case COMPLEX_CST:
2988 return (const_hash_1 (TREE_REALPART (exp)) * 5
2989 + const_hash_1 (TREE_IMAGPART (exp)));
2991 case VECTOR_CST:
2993 unsigned i;
2995 hi = 7 + VECTOR_CST_NELTS (exp);
2997 for (i = 0; i < VECTOR_CST_NELTS (exp); ++i)
2998 hi = hi * 563 + const_hash_1 (VECTOR_CST_ELT (exp, i));
3000 return hi;
3003 case CONSTRUCTOR:
3005 unsigned HOST_WIDE_INT idx;
3006 tree value;
3008 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
3010 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
3011 if (value)
3012 hi = hi * 603 + const_hash_1 (value);
3014 return hi;
3017 case ADDR_EXPR:
3018 case FDESC_EXPR:
3020 struct addr_const value;
3022 decode_addr_const (exp, &value);
3023 switch (GET_CODE (value.base))
3025 case SYMBOL_REF:
3026 /* Don't hash the address of the SYMBOL_REF;
3027 only use the offset and the symbol name. */
3028 hi = value.offset;
3029 p = XSTR (value.base, 0);
3030 for (i = 0; p[i] != 0; i++)
3031 hi = ((hi * 613) + (unsigned) (p[i]));
3032 break;
3034 case LABEL_REF:
3035 hi = (value.offset
3036 + CODE_LABEL_NUMBER (label_ref_label (value.base)) * 13);
3037 break;
3039 default:
3040 gcc_unreachable ();
3043 return hi;
3045 case PLUS_EXPR:
3046 case POINTER_PLUS_EXPR:
3047 case MINUS_EXPR:
3048 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
3049 + const_hash_1 (TREE_OPERAND (exp, 1)));
3051 CASE_CONVERT:
3052 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
3054 default:
3055 /* A language specific constant. Just hash the code. */
3056 return code;
3059 /* Compute hashing function. */
3060 hi = len;
3061 for (i = 0; i < len; i++)
3062 hi = ((hi * 613) + (unsigned) (p[i]));
3064 return hi;
3067 /* Wrapper of compare_constant, for the htab interface. */
3068 bool
3069 tree_descriptor_hasher::equal (constant_descriptor_tree *c1,
3070 constant_descriptor_tree *c2)
3072 if (c1->hash != c2->hash)
3073 return 0;
3074 return compare_constant (c1->value, c2->value);
3077 /* Compare t1 and t2, and return 1 only if they are known to result in
3078 the same bit pattern on output. */
3080 static int
3081 compare_constant (const tree t1, const tree t2)
3083 enum tree_code typecode;
3085 if (t1 == NULL_TREE)
3086 return t2 == NULL_TREE;
3087 if (t2 == NULL_TREE)
3088 return 0;
3090 if (TREE_CODE (t1) != TREE_CODE (t2))
3091 return 0;
3093 switch (TREE_CODE (t1))
3095 case INTEGER_CST:
3096 /* Integer constants are the same only if the same width of type. */
3097 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3098 return 0;
3099 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3100 return 0;
3101 return tree_int_cst_equal (t1, t2);
3103 case REAL_CST:
3104 /* Real constants are the same only if the same width of type. */
3105 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3106 return 0;
3108 return real_identical (&TREE_REAL_CST (t1), &TREE_REAL_CST (t2));
3110 case FIXED_CST:
3111 /* Fixed 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 FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
3117 case STRING_CST:
3118 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3119 return 0;
3121 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
3122 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
3123 TREE_STRING_LENGTH (t1)));
3125 case COMPLEX_CST:
3126 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
3127 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
3129 case VECTOR_CST:
3131 unsigned i;
3133 if (VECTOR_CST_NELTS (t1) != VECTOR_CST_NELTS (t2))
3134 return 0;
3136 for (i = 0; i < VECTOR_CST_NELTS (t1); ++i)
3137 if (!compare_constant (VECTOR_CST_ELT (t1, i),
3138 VECTOR_CST_ELT (t2, i)))
3139 return 0;
3141 return 1;
3144 case CONSTRUCTOR:
3146 vec<constructor_elt, va_gc> *v1, *v2;
3147 unsigned HOST_WIDE_INT idx;
3149 typecode = TREE_CODE (TREE_TYPE (t1));
3150 if (typecode != TREE_CODE (TREE_TYPE (t2)))
3151 return 0;
3153 if (typecode == ARRAY_TYPE)
3155 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
3156 /* For arrays, check that mode, size and storage order match. */
3157 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
3158 || size_1 == -1
3159 || size_1 != int_size_in_bytes (TREE_TYPE (t2))
3160 || TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (t1))
3161 != TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (t2)))
3162 return 0;
3164 else
3166 /* For record and union constructors, require exact type
3167 equality. */
3168 if (TREE_TYPE (t1) != TREE_TYPE (t2))
3169 return 0;
3172 v1 = CONSTRUCTOR_ELTS (t1);
3173 v2 = CONSTRUCTOR_ELTS (t2);
3174 if (vec_safe_length (v1) != vec_safe_length (v2))
3175 return 0;
3177 for (idx = 0; idx < vec_safe_length (v1); ++idx)
3179 constructor_elt *c1 = &(*v1)[idx];
3180 constructor_elt *c2 = &(*v2)[idx];
3182 /* Check that each value is the same... */
3183 if (!compare_constant (c1->value, c2->value))
3184 return 0;
3185 /* ... and that they apply to the same fields! */
3186 if (typecode == ARRAY_TYPE)
3188 if (!compare_constant (c1->index, c2->index))
3189 return 0;
3191 else
3193 if (c1->index != c2->index)
3194 return 0;
3198 return 1;
3201 case ADDR_EXPR:
3202 case FDESC_EXPR:
3204 struct addr_const value1, value2;
3205 enum rtx_code code;
3206 int ret;
3208 decode_addr_const (t1, &value1);
3209 decode_addr_const (t2, &value2);
3211 if (value1.offset != value2.offset)
3212 return 0;
3214 code = GET_CODE (value1.base);
3215 if (code != GET_CODE (value2.base))
3216 return 0;
3218 switch (code)
3220 case SYMBOL_REF:
3221 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3222 break;
3224 case LABEL_REF:
3225 ret = (CODE_LABEL_NUMBER (label_ref_label (value1.base))
3226 == CODE_LABEL_NUMBER (label_ref_label (value2.base)));
3227 break;
3229 default:
3230 gcc_unreachable ();
3232 return ret;
3235 case PLUS_EXPR:
3236 case POINTER_PLUS_EXPR:
3237 case MINUS_EXPR:
3238 case RANGE_EXPR:
3239 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3240 && compare_constant (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3242 CASE_CONVERT:
3243 case VIEW_CONVERT_EXPR:
3244 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3246 default:
3247 return 0;
3250 gcc_unreachable ();
3253 /* Return the section into which constant EXP should be placed. */
3255 static section *
3256 get_constant_section (tree exp, unsigned int align)
3258 return targetm.asm_out.select_section (exp,
3259 compute_reloc_for_constant (exp),
3260 align);
3263 /* Return the size of constant EXP in bytes. */
3265 static HOST_WIDE_INT
3266 get_constant_size (tree exp)
3268 HOST_WIDE_INT size;
3270 size = int_size_in_bytes (TREE_TYPE (exp));
3271 if (TREE_CODE (exp) == STRING_CST)
3272 size = MAX (TREE_STRING_LENGTH (exp), size);
3273 return size;
3276 /* Subroutine of output_constant_def:
3277 No constant equal to EXP is known to have been output.
3278 Make a constant descriptor to enter EXP in the hash table.
3279 Assign the label number and construct RTL to refer to the
3280 constant's location in memory.
3281 Caller is responsible for updating the hash table. */
3283 static struct constant_descriptor_tree *
3284 build_constant_desc (tree exp)
3286 struct constant_descriptor_tree *desc;
3287 rtx symbol, rtl;
3288 char label[256];
3289 int labelno;
3290 tree decl;
3292 desc = ggc_alloc<constant_descriptor_tree> ();
3293 desc->value = exp;
3295 /* Create a string containing the label name, in LABEL. */
3296 labelno = const_labelno++;
3297 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3299 /* Construct the VAR_DECL associated with the constant. */
3300 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3301 TREE_TYPE (exp));
3302 DECL_ARTIFICIAL (decl) = 1;
3303 DECL_IGNORED_P (decl) = 1;
3304 TREE_READONLY (decl) = 1;
3305 TREE_STATIC (decl) = 1;
3306 TREE_ADDRESSABLE (decl) = 1;
3307 /* We don't set the RTL yet as this would cause varpool to assume that the
3308 variable is referenced. Moreover, it would just be dropped in LTO mode.
3309 Instead we set the flag that will be recognized in make_decl_rtl. */
3310 DECL_IN_CONSTANT_POOL (decl) = 1;
3311 DECL_INITIAL (decl) = desc->value;
3312 /* ??? CONSTANT_ALIGNMENT hasn't been updated for vector types on most
3313 architectures so use DATA_ALIGNMENT as well, except for strings. */
3314 if (TREE_CODE (exp) == STRING_CST)
3316 SET_DECL_ALIGN (decl, CONSTANT_ALIGNMENT (exp, DECL_ALIGN (decl)));
3318 else
3319 align_variable (decl, 0);
3321 /* Now construct the SYMBOL_REF and the MEM. */
3322 if (use_object_blocks_p ())
3324 int align = (TREE_CODE (decl) == CONST_DECL
3325 || (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
3326 ? DECL_ALIGN (decl)
3327 : symtab_node::get (decl)->definition_alignment ());
3328 section *sect = get_constant_section (exp, align);
3329 symbol = create_block_symbol (ggc_strdup (label),
3330 get_block_for_section (sect), -1);
3332 else
3333 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3334 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3335 SET_SYMBOL_REF_DECL (symbol, decl);
3336 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3338 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3339 set_mem_attributes (rtl, exp, 1);
3340 set_mem_alias_set (rtl, 0);
3342 /* Putting EXP into the literal pool might have imposed a different
3343 alignment which should be visible in the RTX as well. */
3344 set_mem_align (rtl, DECL_ALIGN (decl));
3346 /* We cannot share RTX'es in pool entries.
3347 Mark this piece of RTL as required for unsharing. */
3348 RTX_FLAG (rtl, used) = 1;
3350 /* Set flags or add text to the name to record information, such as
3351 that it is a local symbol. If the name is changed, the macro
3352 ASM_OUTPUT_LABELREF will have to know how to strip this
3353 information. This call might invalidate our local variable
3354 SYMBOL; we can't use it afterward. */
3355 targetm.encode_section_info (exp, rtl, true);
3357 desc->rtl = rtl;
3359 return desc;
3362 /* Return an rtx representing a reference to constant data in memory
3363 for the constant expression EXP.
3365 If assembler code for such a constant has already been output,
3366 return an rtx to refer to it.
3367 Otherwise, output such a constant in memory
3368 and generate an rtx for it.
3370 If DEFER is nonzero, this constant can be deferred and output only
3371 if referenced in the function after all optimizations.
3373 `const_desc_table' records which constants already have label strings. */
3376 output_constant_def (tree exp, int defer)
3378 struct constant_descriptor_tree *desc;
3379 struct constant_descriptor_tree key;
3381 /* Look up EXP in the table of constant descriptors. If we didn't find
3382 it, create a new one. */
3383 key.value = exp;
3384 key.hash = const_hash_1 (exp);
3385 constant_descriptor_tree **loc
3386 = const_desc_htab->find_slot_with_hash (&key, key.hash, INSERT);
3388 desc = *loc;
3389 if (desc == 0)
3391 desc = build_constant_desc (exp);
3392 desc->hash = key.hash;
3393 *loc = desc;
3396 maybe_output_constant_def_contents (desc, defer);
3397 return desc->rtl;
3400 /* Subroutine of output_constant_def: Decide whether or not we need to
3401 output the constant DESC now, and if so, do it. */
3402 static void
3403 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3404 int defer)
3406 rtx symbol = XEXP (desc->rtl, 0);
3407 tree exp = desc->value;
3409 if (flag_syntax_only)
3410 return;
3412 if (TREE_ASM_WRITTEN (exp))
3413 /* Already output; don't do it again. */
3414 return;
3416 /* We can always defer constants as long as the context allows
3417 doing so. */
3418 if (defer)
3420 /* Increment n_deferred_constants if it exists. It needs to be at
3421 least as large as the number of constants actually referred to
3422 by the function. If it's too small we'll stop looking too early
3423 and fail to emit constants; if it's too large we'll only look
3424 through the entire function when we could have stopped earlier. */
3425 if (cfun)
3426 n_deferred_constants++;
3427 return;
3430 output_constant_def_contents (symbol);
3433 /* Subroutine of output_constant_def_contents. Output the definition
3434 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3435 constant's alignment in bits. */
3437 static void
3438 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3440 HOST_WIDE_INT size;
3442 size = get_constant_size (exp);
3444 /* Do any machine/system dependent processing of the constant. */
3445 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3447 /* Output the value of EXP. */
3448 output_constant (exp, size, align, false);
3450 targetm.asm_out.decl_end ();
3453 /* We must output the constant data referred to by SYMBOL; do so. */
3455 static void
3456 output_constant_def_contents (rtx symbol)
3458 tree decl = SYMBOL_REF_DECL (symbol);
3459 tree exp = DECL_INITIAL (decl);
3460 bool asan_protected = false;
3462 /* Make sure any other constants whose addresses appear in EXP
3463 are assigned label numbers. */
3464 output_addressed_constants (exp);
3466 /* We are no longer deferring this constant. */
3467 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3469 if ((flag_sanitize & SANITIZE_ADDRESS)
3470 && TREE_CODE (exp) == STRING_CST
3471 && asan_protect_global (exp))
3473 asan_protected = true;
3474 SET_DECL_ALIGN (decl, MAX (DECL_ALIGN (decl),
3475 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT));
3478 /* If the constant is part of an object block, make sure that the
3479 decl has been positioned within its block, but do not write out
3480 its definition yet. output_object_blocks will do that later. */
3481 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3482 place_block_symbol (symbol);
3483 else
3485 int align = (TREE_CODE (decl) == CONST_DECL
3486 || (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
3487 ? DECL_ALIGN (decl)
3488 : symtab_node::get (decl)->definition_alignment ());
3489 switch_to_section (get_constant_section (exp, align));
3490 if (align > BITS_PER_UNIT)
3491 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3492 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3493 if (asan_protected)
3495 HOST_WIDE_INT size = get_constant_size (exp);
3496 assemble_zeros (asan_red_zone_size (size));
3501 /* Look up EXP in the table of constant descriptors. Return the rtl
3502 if it has been emitted, else null. */
3505 lookup_constant_def (tree exp)
3507 struct constant_descriptor_tree key;
3509 key.value = exp;
3510 key.hash = const_hash_1 (exp);
3511 constant_descriptor_tree *desc
3512 = const_desc_htab->find_with_hash (&key, key.hash);
3514 return (desc ? desc->rtl : NULL_RTX);
3517 /* Return a tree representing a reference to constant data in memory
3518 for the constant expression EXP.
3520 This is the counterpart of output_constant_def at the Tree level. */
3522 tree
3523 tree_output_constant_def (tree exp)
3525 struct constant_descriptor_tree *desc, key;
3526 tree decl;
3528 /* Look up EXP in the table of constant descriptors. If we didn't find
3529 it, create a new one. */
3530 key.value = exp;
3531 key.hash = const_hash_1 (exp);
3532 constant_descriptor_tree **loc
3533 = const_desc_htab->find_slot_with_hash (&key, key.hash, INSERT);
3535 desc = *loc;
3536 if (desc == 0)
3538 desc = build_constant_desc (exp);
3539 desc->hash = key.hash;
3540 *loc = desc;
3543 decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3544 varpool_node::finalize_decl (decl);
3545 return decl;
3548 struct GTY((chain_next ("%h.next"), for_user)) constant_descriptor_rtx {
3549 struct constant_descriptor_rtx *next;
3550 rtx mem;
3551 rtx sym;
3552 rtx constant;
3553 HOST_WIDE_INT offset;
3554 hashval_t hash;
3555 machine_mode mode;
3556 unsigned int align;
3557 int labelno;
3558 int mark;
3561 struct const_rtx_desc_hasher : ggc_ptr_hash<constant_descriptor_rtx>
3563 static hashval_t hash (constant_descriptor_rtx *);
3564 static bool equal (constant_descriptor_rtx *, constant_descriptor_rtx *);
3567 /* Used in the hash tables to avoid outputting the same constant
3568 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3569 are output once per function, not once per file. */
3570 /* ??? Only a few targets need per-function constant pools. Most
3571 can use one per-file pool. Should add a targetm bit to tell the
3572 difference. */
3574 struct GTY(()) rtx_constant_pool {
3575 /* Pointers to first and last constant in pool, as ordered by offset. */
3576 struct constant_descriptor_rtx *first;
3577 struct constant_descriptor_rtx *last;
3579 /* Hash facility for making memory-constants from constant rtl-expressions.
3580 It is used on RISC machines where immediate integer arguments and
3581 constant addresses are restricted so that such constants must be stored
3582 in memory. */
3583 hash_table<const_rtx_desc_hasher> *const_rtx_htab;
3585 /* Current offset in constant pool (does not include any
3586 machine-specific header). */
3587 HOST_WIDE_INT offset;
3590 /* Hash and compare functions for const_rtx_htab. */
3592 hashval_t
3593 const_rtx_desc_hasher::hash (constant_descriptor_rtx *desc)
3595 return desc->hash;
3598 bool
3599 const_rtx_desc_hasher::equal (constant_descriptor_rtx *x,
3600 constant_descriptor_rtx *y)
3602 if (x->mode != y->mode)
3603 return 0;
3604 return rtx_equal_p (x->constant, y->constant);
3607 /* Hash one component of a constant. */
3609 static hashval_t
3610 const_rtx_hash_1 (const_rtx x)
3612 unsigned HOST_WIDE_INT hwi;
3613 machine_mode mode;
3614 enum rtx_code code;
3615 hashval_t h;
3616 int i;
3618 code = GET_CODE (x);
3619 mode = GET_MODE (x);
3620 h = (hashval_t) code * 1048573 + mode;
3622 switch (code)
3624 case CONST_INT:
3625 hwi = INTVAL (x);
3627 fold_hwi:
3629 int shift = sizeof (hashval_t) * CHAR_BIT;
3630 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3632 h ^= (hashval_t) hwi;
3633 for (i = 1; i < n; ++i)
3635 hwi >>= shift;
3636 h ^= (hashval_t) hwi;
3639 break;
3641 case CONST_WIDE_INT:
3642 hwi = 0;
3644 for (i = 0; i < CONST_WIDE_INT_NUNITS (x); i++)
3645 hwi ^= CONST_WIDE_INT_ELT (x, i);
3646 goto fold_hwi;
3649 case CONST_DOUBLE:
3650 if (TARGET_SUPPORTS_WIDE_INT == 0 && mode == VOIDmode)
3652 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3653 goto fold_hwi;
3655 else
3656 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3657 break;
3659 case CONST_FIXED:
3660 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3661 break;
3663 case SYMBOL_REF:
3664 h ^= htab_hash_string (XSTR (x, 0));
3665 break;
3667 case LABEL_REF:
3668 h = h * 251 + CODE_LABEL_NUMBER (label_ref_label (x));
3669 break;
3671 case UNSPEC:
3672 case UNSPEC_VOLATILE:
3673 h = h * 251 + XINT (x, 1);
3674 break;
3676 default:
3677 break;
3680 return h;
3683 /* Compute a hash value for X, which should be a constant. */
3685 static hashval_t
3686 const_rtx_hash (rtx x)
3688 hashval_t h = 0;
3689 subrtx_iterator::array_type array;
3690 FOR_EACH_SUBRTX (iter, array, x, ALL)
3691 h = h * 509 + const_rtx_hash_1 (*iter);
3692 return h;
3696 /* Create and return a new rtx constant pool. */
3698 static struct rtx_constant_pool *
3699 create_constant_pool (void)
3701 struct rtx_constant_pool *pool;
3703 pool = ggc_alloc<rtx_constant_pool> ();
3704 pool->const_rtx_htab = hash_table<const_rtx_desc_hasher>::create_ggc (31);
3705 pool->first = NULL;
3706 pool->last = NULL;
3707 pool->offset = 0;
3708 return pool;
3711 /* Initialize constant pool hashing for a new function. */
3713 void
3714 init_varasm_status (void)
3716 crtl->varasm.pool = create_constant_pool ();
3717 crtl->varasm.deferred_constants = 0;
3720 /* Given a MINUS expression, simplify it if both sides
3721 include the same symbol. */
3724 simplify_subtraction (rtx x)
3726 rtx r = simplify_rtx (x);
3727 return r ? r : x;
3730 /* Given a constant rtx X, make (or find) a memory constant for its value
3731 and return a MEM rtx to refer to it in memory. */
3734 force_const_mem (machine_mode mode, rtx x)
3736 struct constant_descriptor_rtx *desc, tmp;
3737 struct rtx_constant_pool *pool;
3738 char label[256];
3739 rtx def, symbol;
3740 hashval_t hash;
3741 unsigned int align;
3742 constant_descriptor_rtx **slot;
3744 /* If we're not allowed to drop X into the constant pool, don't. */
3745 if (targetm.cannot_force_const_mem (mode, x))
3746 return NULL_RTX;
3748 /* Record that this function has used a constant pool entry. */
3749 crtl->uses_const_pool = 1;
3751 /* Decide which pool to use. */
3752 pool = (targetm.use_blocks_for_constant_p (mode, x)
3753 ? shared_constant_pool
3754 : crtl->varasm.pool);
3756 /* Lookup the value in the hashtable. */
3757 tmp.constant = x;
3758 tmp.mode = mode;
3759 hash = const_rtx_hash (x);
3760 slot = pool->const_rtx_htab->find_slot_with_hash (&tmp, hash, INSERT);
3761 desc = *slot;
3763 /* If the constant was already present, return its memory. */
3764 if (desc)
3765 return copy_rtx (desc->mem);
3767 /* Otherwise, create a new descriptor. */
3768 desc = ggc_alloc<constant_descriptor_rtx> ();
3769 *slot = desc;
3771 /* Align the location counter as required by EXP's data type. */
3772 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3774 tree type = lang_hooks.types.type_for_mode (mode, 0);
3775 if (type != NULL_TREE)
3776 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3778 pool->offset += (align / BITS_PER_UNIT) - 1;
3779 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3781 desc->next = NULL;
3782 desc->constant = copy_rtx (tmp.constant);
3783 desc->offset = pool->offset;
3784 desc->hash = hash;
3785 desc->mode = mode;
3786 desc->align = align;
3787 desc->labelno = const_labelno;
3788 desc->mark = 0;
3790 pool->offset += GET_MODE_SIZE (mode);
3791 if (pool->last)
3792 pool->last->next = desc;
3793 else
3794 pool->first = pool->last = desc;
3795 pool->last = desc;
3797 /* Create a string containing the label name, in LABEL. */
3798 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3799 ++const_labelno;
3801 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3802 the constants pool. */
3803 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3805 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3806 symbol = create_block_symbol (ggc_strdup (label),
3807 get_block_for_section (sect), -1);
3809 else
3810 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3811 desc->sym = symbol;
3812 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3813 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3814 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3816 /* Construct the MEM. */
3817 desc->mem = def = gen_const_mem (mode, symbol);
3818 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3819 set_mem_align (def, align);
3821 /* If we're dropping a label to the constant pool, make sure we
3822 don't delete it. */
3823 if (GET_CODE (x) == LABEL_REF)
3824 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3826 return copy_rtx (def);
3829 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3832 get_pool_constant (const_rtx addr)
3834 return SYMBOL_REF_CONSTANT (addr)->constant;
3837 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3838 and whether it has been output or not. */
3841 get_pool_constant_mark (rtx addr, bool *pmarked)
3843 struct constant_descriptor_rtx *desc;
3845 desc = SYMBOL_REF_CONSTANT (addr);
3846 *pmarked = (desc->mark != 0);
3847 return desc->constant;
3850 /* Similar, return the mode. */
3852 machine_mode
3853 get_pool_mode (const_rtx addr)
3855 return SYMBOL_REF_CONSTANT (addr)->mode;
3858 /* Return TRUE if and only if the constant pool has no entries. Note
3859 that even entries we might end up choosing not to emit are counted
3860 here, so there is the potential for missed optimizations. */
3862 bool
3863 constant_pool_empty_p (void)
3865 return crtl->varasm.pool->first == NULL;
3868 /* Worker function for output_constant_pool_1. Emit assembly for X
3869 in MODE with known alignment ALIGN. */
3871 static void
3872 output_constant_pool_2 (machine_mode mode, rtx x, unsigned int align)
3874 switch (GET_MODE_CLASS (mode))
3876 case MODE_FLOAT:
3877 case MODE_DECIMAL_FLOAT:
3879 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3880 assemble_real (*CONST_DOUBLE_REAL_VALUE (x), mode, align, false);
3881 break;
3884 case MODE_INT:
3885 case MODE_PARTIAL_INT:
3886 case MODE_FRACT:
3887 case MODE_UFRACT:
3888 case MODE_ACCUM:
3889 case MODE_UACCUM:
3890 case MODE_POINTER_BOUNDS:
3891 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3892 break;
3894 case MODE_VECTOR_FLOAT:
3895 case MODE_VECTOR_INT:
3896 case MODE_VECTOR_FRACT:
3897 case MODE_VECTOR_UFRACT:
3898 case MODE_VECTOR_ACCUM:
3899 case MODE_VECTOR_UACCUM:
3901 int i, units;
3902 machine_mode submode = GET_MODE_INNER (mode);
3903 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3905 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3906 units = CONST_VECTOR_NUNITS (x);
3908 for (i = 0; i < units; i++)
3910 rtx elt = CONST_VECTOR_ELT (x, i);
3911 output_constant_pool_2 (submode, elt, i ? subalign : align);
3914 break;
3916 default:
3917 gcc_unreachable ();
3921 /* Worker function for output_constant_pool. Emit constant DESC,
3922 giving it ALIGN bits of alignment. */
3924 static void
3925 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3926 unsigned int align)
3928 rtx x, tmp;
3930 x = desc->constant;
3932 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3933 whose CODE_LABEL has been deleted. This can occur if a jump table
3934 is eliminated by optimization. If so, write a constant of zero
3935 instead. Note that this can also happen by turning the
3936 CODE_LABEL into a NOTE. */
3937 /* ??? This seems completely and utterly wrong. Certainly it's
3938 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3939 functioning even with rtx_insn::deleted and friends. */
3941 tmp = x;
3942 switch (GET_CODE (tmp))
3944 case CONST:
3945 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3946 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
3947 break;
3948 tmp = XEXP (XEXP (tmp, 0), 0);
3949 /* FALLTHRU */
3951 case LABEL_REF:
3953 rtx_insn *insn = label_ref_label (tmp);
3954 gcc_assert (!insn->deleted ());
3955 gcc_assert (!NOTE_P (insn)
3956 || NOTE_KIND (insn) != NOTE_INSN_DELETED);
3957 break;
3960 default:
3961 break;
3964 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3965 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3966 align, desc->labelno, done);
3967 #endif
3969 assemble_align (align);
3971 /* Output the label. */
3972 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3974 /* Output the data.
3975 Pass actual alignment value while emitting string constant to asm code
3976 as function 'output_constant_pool_1' explicitly passes the alignment as 1
3977 assuming that the data is already aligned which prevents the generation
3978 of fix-up table entries. */
3979 output_constant_pool_2 (desc->mode, x, desc->align);
3981 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3982 sections have proper size. */
3983 if (align > GET_MODE_BITSIZE (desc->mode)
3984 && in_section
3985 && (in_section->common.flags & SECTION_MERGE))
3986 assemble_align (align);
3988 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3989 done:
3990 #endif
3991 return;
3994 /* Recompute the offsets of entries in POOL, and the overall size of
3995 POOL. Do this after calling mark_constant_pool to ensure that we
3996 are computing the offset values for the pool which we will actually
3997 emit. */
3999 static void
4000 recompute_pool_offsets (struct rtx_constant_pool *pool)
4002 struct constant_descriptor_rtx *desc;
4003 pool->offset = 0;
4005 for (desc = pool->first; desc ; desc = desc->next)
4006 if (desc->mark)
4008 /* Recalculate offset. */
4009 unsigned int align = desc->align;
4010 pool->offset += (align / BITS_PER_UNIT) - 1;
4011 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
4012 desc->offset = pool->offset;
4013 pool->offset += GET_MODE_SIZE (desc->mode);
4017 /* Mark all constants that are referenced by SYMBOL_REFs in X.
4018 Emit referenced deferred strings. */
4020 static void
4021 mark_constants_in_pattern (rtx insn)
4023 subrtx_iterator::array_type array;
4024 FOR_EACH_SUBRTX (iter, array, PATTERN (insn), ALL)
4026 const_rtx x = *iter;
4027 if (GET_CODE (x) == SYMBOL_REF)
4029 if (CONSTANT_POOL_ADDRESS_P (x))
4031 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
4032 if (desc->mark == 0)
4034 desc->mark = 1;
4035 iter.substitute (desc->constant);
4038 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
4040 tree decl = SYMBOL_REF_DECL (x);
4041 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
4043 n_deferred_constants--;
4044 output_constant_def_contents (CONST_CAST_RTX (x));
4051 /* Look through appropriate parts of INSN, marking all entries in the
4052 constant pool which are actually being used. Entries that are only
4053 referenced by other constants are also marked as used. Emit
4054 deferred strings that are used. */
4056 static void
4057 mark_constants (rtx_insn *insn)
4059 if (!INSN_P (insn))
4060 return;
4062 /* Insns may appear inside a SEQUENCE. Only check the patterns of
4063 insns, not any notes that may be attached. We don't want to mark
4064 a constant just because it happens to appear in a REG_EQUIV note. */
4065 if (rtx_sequence *seq = dyn_cast <rtx_sequence *> (PATTERN (insn)))
4067 int i, n = seq->len ();
4068 for (i = 0; i < n; ++i)
4070 rtx subinsn = seq->element (i);
4071 if (INSN_P (subinsn))
4072 mark_constants_in_pattern (subinsn);
4075 else
4076 mark_constants_in_pattern (insn);
4079 /* Look through the instructions for this function, and mark all the
4080 entries in POOL which are actually being used. Emit deferred constants
4081 which have indeed been used. */
4083 static void
4084 mark_constant_pool (void)
4086 rtx_insn *insn;
4088 if (!crtl->uses_const_pool && n_deferred_constants == 0)
4089 return;
4091 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4092 mark_constants (insn);
4095 /* Write all the constants in POOL. */
4097 static void
4098 output_constant_pool_contents (struct rtx_constant_pool *pool)
4100 struct constant_descriptor_rtx *desc;
4102 for (desc = pool->first; desc ; desc = desc->next)
4103 if (desc->mark)
4105 /* If the constant is part of an object_block, make sure that
4106 the constant has been positioned within its block, but do not
4107 write out its definition yet. output_object_blocks will do
4108 that later. */
4109 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
4110 && SYMBOL_REF_BLOCK (desc->sym))
4111 place_block_symbol (desc->sym);
4112 else
4114 switch_to_section (targetm.asm_out.select_rtx_section
4115 (desc->mode, desc->constant, desc->align));
4116 output_constant_pool_1 (desc, desc->align);
4121 /* Mark all constants that are used in the current function, then write
4122 out the function's private constant pool. */
4124 static void
4125 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
4126 tree fndecl ATTRIBUTE_UNUSED)
4128 struct rtx_constant_pool *pool = crtl->varasm.pool;
4130 /* It is possible for gcc to call force_const_mem and then to later
4131 discard the instructions which refer to the constant. In such a
4132 case we do not need to output the constant. */
4133 mark_constant_pool ();
4135 /* Having marked the constant pool entries we'll actually emit, we
4136 now need to rebuild the offset information, which may have become
4137 stale. */
4138 recompute_pool_offsets (pool);
4140 #ifdef ASM_OUTPUT_POOL_PROLOGUE
4141 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
4142 #endif
4144 output_constant_pool_contents (pool);
4146 #ifdef ASM_OUTPUT_POOL_EPILOGUE
4147 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
4148 #endif
4151 /* Write the contents of the shared constant pool. */
4153 void
4154 output_shared_constant_pool (void)
4156 output_constant_pool_contents (shared_constant_pool);
4159 /* Determine what kind of relocations EXP may need. */
4162 compute_reloc_for_constant (tree exp)
4164 int reloc = 0, reloc2;
4165 tree tem;
4167 switch (TREE_CODE (exp))
4169 case ADDR_EXPR:
4170 case FDESC_EXPR:
4171 /* Go inside any operations that get_inner_reference can handle and see
4172 if what's inside is a constant: no need to do anything here for
4173 addresses of variables or functions. */
4174 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4175 tem = TREE_OPERAND (tem, 0))
4178 if (TREE_CODE (tem) == MEM_REF
4179 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4181 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4182 break;
4185 if (!targetm.binds_local_p (tem))
4186 reloc |= 2;
4187 else
4188 reloc |= 1;
4189 break;
4191 case PLUS_EXPR:
4192 case POINTER_PLUS_EXPR:
4193 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4194 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4195 break;
4197 case MINUS_EXPR:
4198 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4199 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4200 /* The difference of two local labels is computable at link time. */
4201 if (reloc == 1 && reloc2 == 1)
4202 reloc = 0;
4203 else
4204 reloc |= reloc2;
4205 break;
4207 CASE_CONVERT:
4208 case VIEW_CONVERT_EXPR:
4209 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4210 break;
4212 case CONSTRUCTOR:
4214 unsigned HOST_WIDE_INT idx;
4215 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4216 if (tem != 0)
4217 reloc |= compute_reloc_for_constant (tem);
4219 break;
4221 default:
4222 break;
4224 return reloc;
4227 /* Find all the constants whose addresses are referenced inside of EXP,
4228 and make sure assembler code with a label has been output for each one.
4229 Indicate whether an ADDR_EXPR has been encountered. */
4231 static void
4232 output_addressed_constants (tree exp)
4234 tree tem;
4236 switch (TREE_CODE (exp))
4238 case ADDR_EXPR:
4239 case FDESC_EXPR:
4240 /* Go inside any operations that get_inner_reference can handle and see
4241 if what's inside is a constant: no need to do anything here for
4242 addresses of variables or functions. */
4243 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4244 tem = TREE_OPERAND (tem, 0))
4247 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4248 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4249 tem = DECL_INITIAL (tem);
4251 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4252 output_constant_def (tem, 0);
4254 if (TREE_CODE (tem) == MEM_REF)
4255 output_addressed_constants (TREE_OPERAND (tem, 0));
4256 break;
4258 case PLUS_EXPR:
4259 case POINTER_PLUS_EXPR:
4260 case MINUS_EXPR:
4261 output_addressed_constants (TREE_OPERAND (exp, 1));
4262 gcc_fallthrough ();
4264 CASE_CONVERT:
4265 case VIEW_CONVERT_EXPR:
4266 output_addressed_constants (TREE_OPERAND (exp, 0));
4267 break;
4269 case CONSTRUCTOR:
4271 unsigned HOST_WIDE_INT idx;
4272 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4273 if (tem != 0)
4274 output_addressed_constants (tem);
4276 break;
4278 default:
4279 break;
4283 /* Whether a constructor CTOR is a valid static constant initializer if all
4284 its elements are. This used to be internal to initializer_constant_valid_p
4285 and has been exposed to let other functions like categorize_ctor_elements
4286 evaluate the property while walking a constructor for other purposes. */
4288 bool
4289 constructor_static_from_elts_p (const_tree ctor)
4291 return (TREE_CONSTANT (ctor)
4292 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4293 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4294 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4297 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4298 tree *cache);
4300 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4301 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4302 which are valid when ENDTYPE is an integer of any size; in
4303 particular, this does not accept a pointer minus a constant. This
4304 returns null_pointer_node if the VALUE is an absolute constant
4305 which can be used to initialize a static variable. Otherwise it
4306 returns NULL. */
4308 static tree
4309 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4311 tree op0, op1;
4313 if (!INTEGRAL_TYPE_P (endtype))
4314 return NULL_TREE;
4316 op0 = TREE_OPERAND (value, 0);
4317 op1 = TREE_OPERAND (value, 1);
4319 /* Like STRIP_NOPS except allow the operand mode to widen. This
4320 works around a feature of fold that simplifies (int)(p1 - p2) to
4321 ((int)p1 - (int)p2) under the theory that the narrower operation
4322 is cheaper. */
4324 while (CONVERT_EXPR_P (op0)
4325 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4327 tree inner = TREE_OPERAND (op0, 0);
4328 if (inner == error_mark_node
4329 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4330 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
4331 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4332 break;
4333 op0 = inner;
4336 while (CONVERT_EXPR_P (op1)
4337 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4339 tree inner = TREE_OPERAND (op1, 0);
4340 if (inner == error_mark_node
4341 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4342 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
4343 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4344 break;
4345 op1 = inner;
4348 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4349 if (!op0)
4350 return NULL_TREE;
4352 op1 = initializer_constant_valid_p_1 (op1, endtype,
4353 cache ? cache + 2 : NULL);
4354 /* Both initializers must be known. */
4355 if (op1)
4357 if (op0 == op1
4358 && (op0 == null_pointer_node
4359 || TREE_CODE (value) == MINUS_EXPR))
4360 return null_pointer_node;
4362 /* Support differences between labels. */
4363 if (TREE_CODE (op0) == LABEL_DECL
4364 && TREE_CODE (op1) == LABEL_DECL)
4365 return null_pointer_node;
4367 if (TREE_CODE (op0) == STRING_CST
4368 && TREE_CODE (op1) == STRING_CST
4369 && operand_equal_p (op0, op1, 1))
4370 return null_pointer_node;
4373 return NULL_TREE;
4376 /* Helper function of initializer_constant_valid_p.
4377 Return nonzero if VALUE is a valid constant-valued expression
4378 for use in initializing a static variable; one that can be an
4379 element of a "constant" initializer.
4381 Return null_pointer_node if the value is absolute;
4382 if it is relocatable, return the variable that determines the relocation.
4383 We assume that VALUE has been folded as much as possible;
4384 therefore, we do not need to check for such things as
4385 arithmetic-combinations of integers.
4387 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4389 static tree
4390 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4392 tree ret;
4394 switch (TREE_CODE (value))
4396 case CONSTRUCTOR:
4397 if (constructor_static_from_elts_p (value))
4399 unsigned HOST_WIDE_INT idx;
4400 tree elt;
4401 bool absolute = true;
4403 if (cache && cache[0] == value)
4404 return cache[1];
4405 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4407 tree reloc;
4408 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4409 NULL);
4410 if (!reloc
4411 /* An absolute value is required with reverse SSO. */
4412 || (reloc != null_pointer_node
4413 && TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (value))
4414 && !AGGREGATE_TYPE_P (TREE_TYPE (elt))))
4416 if (cache)
4418 cache[0] = value;
4419 cache[1] = NULL_TREE;
4421 return NULL_TREE;
4423 if (reloc != null_pointer_node)
4424 absolute = false;
4426 /* For a non-absolute relocation, there is no single
4427 variable that can be "the variable that determines the
4428 relocation." */
4429 if (cache)
4431 cache[0] = value;
4432 cache[1] = absolute ? null_pointer_node : error_mark_node;
4434 return absolute ? null_pointer_node : error_mark_node;
4437 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4439 case INTEGER_CST:
4440 case VECTOR_CST:
4441 case REAL_CST:
4442 case FIXED_CST:
4443 case STRING_CST:
4444 case COMPLEX_CST:
4445 return null_pointer_node;
4447 case ADDR_EXPR:
4448 case FDESC_EXPR:
4450 tree op0 = staticp (TREE_OPERAND (value, 0));
4451 if (op0)
4453 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4454 to be a constant, this is old-skool offsetof-like nonsense. */
4455 if (TREE_CODE (op0) == INDIRECT_REF
4456 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4457 return null_pointer_node;
4458 /* Taking the address of a nested function involves a trampoline,
4459 unless we don't need or want one. */
4460 if (TREE_CODE (op0) == FUNCTION_DECL
4461 && DECL_STATIC_CHAIN (op0)
4462 && !TREE_NO_TRAMPOLINE (value))
4463 return NULL_TREE;
4464 /* "&{...}" requires a temporary to hold the constructed
4465 object. */
4466 if (TREE_CODE (op0) == CONSTRUCTOR)
4467 return NULL_TREE;
4469 return op0;
4472 case NON_LVALUE_EXPR:
4473 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4474 endtype, cache);
4476 case VIEW_CONVERT_EXPR:
4478 tree src = TREE_OPERAND (value, 0);
4479 tree src_type = TREE_TYPE (src);
4480 tree dest_type = TREE_TYPE (value);
4482 /* Allow view-conversions from aggregate to non-aggregate type only
4483 if the bit pattern is fully preserved afterwards; otherwise, the
4484 RTL expander won't be able to apply a subsequent transformation
4485 to the underlying constructor. */
4486 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4488 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4489 return initializer_constant_valid_p_1 (src, endtype, cache);
4490 else
4491 return NULL_TREE;
4494 /* Allow all other kinds of view-conversion. */
4495 return initializer_constant_valid_p_1 (src, endtype, cache);
4498 CASE_CONVERT:
4500 tree src = TREE_OPERAND (value, 0);
4501 tree src_type = TREE_TYPE (src);
4502 tree dest_type = TREE_TYPE (value);
4504 /* Allow conversions between pointer types, floating-point
4505 types, and offset types. */
4506 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4507 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4508 || (TREE_CODE (dest_type) == OFFSET_TYPE
4509 && TREE_CODE (src_type) == OFFSET_TYPE))
4510 return initializer_constant_valid_p_1 (src, endtype, cache);
4512 /* Allow length-preserving conversions between integer types. */
4513 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4514 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4515 return initializer_constant_valid_p_1 (src, endtype, cache);
4517 /* Allow conversions between other integer types only if
4518 explicit value. Don't allow sign-extension to a type larger
4519 than word and pointer, there aren't relocations that would
4520 allow to sign extend it to a wider type. */
4521 if (INTEGRAL_TYPE_P (dest_type)
4522 && INTEGRAL_TYPE_P (src_type)
4523 && (TYPE_UNSIGNED (src_type)
4524 || TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type)
4525 || TYPE_PRECISION (dest_type) <= BITS_PER_WORD
4526 || TYPE_PRECISION (dest_type) <= POINTER_SIZE))
4528 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4529 if (inner == null_pointer_node)
4530 return null_pointer_node;
4531 break;
4534 /* Allow (int) &foo provided int is as wide as a pointer. */
4535 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4536 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4537 return initializer_constant_valid_p_1 (src, endtype, cache);
4539 /* Likewise conversions from int to pointers, but also allow
4540 conversions from 0. */
4541 if ((POINTER_TYPE_P (dest_type)
4542 || TREE_CODE (dest_type) == OFFSET_TYPE)
4543 && INTEGRAL_TYPE_P (src_type))
4545 if (TREE_CODE (src) == INTEGER_CST
4546 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4547 return null_pointer_node;
4548 if (integer_zerop (src))
4549 return null_pointer_node;
4550 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4551 return initializer_constant_valid_p_1 (src, endtype, cache);
4554 /* Allow conversions to struct or union types if the value
4555 inside is okay. */
4556 if (TREE_CODE (dest_type) == RECORD_TYPE
4557 || TREE_CODE (dest_type) == UNION_TYPE)
4558 return initializer_constant_valid_p_1 (src, endtype, cache);
4560 break;
4562 case POINTER_PLUS_EXPR:
4563 case PLUS_EXPR:
4564 /* Any valid floating-point constants will have been folded by now;
4565 with -frounding-math we hit this with addition of two constants. */
4566 if (TREE_CODE (endtype) == REAL_TYPE)
4567 return NULL_TREE;
4568 if (cache && cache[0] == value)
4569 return cache[1];
4570 if (! INTEGRAL_TYPE_P (endtype)
4571 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4573 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4574 tree valid0
4575 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4576 endtype, ncache);
4577 tree valid1
4578 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4579 endtype, ncache + 2);
4580 /* If either term is absolute, use the other term's relocation. */
4581 if (valid0 == null_pointer_node)
4582 ret = valid1;
4583 else if (valid1 == null_pointer_node)
4584 ret = valid0;
4585 /* Support narrowing pointer differences. */
4586 else
4587 ret = narrowing_initializer_constant_valid_p (value, endtype,
4588 ncache);
4590 else
4591 /* Support narrowing pointer differences. */
4592 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4593 if (cache)
4595 cache[0] = value;
4596 cache[1] = ret;
4598 return ret;
4600 case MINUS_EXPR:
4601 if (TREE_CODE (endtype) == REAL_TYPE)
4602 return NULL_TREE;
4603 if (cache && cache[0] == value)
4604 return cache[1];
4605 if (! INTEGRAL_TYPE_P (endtype)
4606 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4608 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4609 tree valid0
4610 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4611 endtype, ncache);
4612 tree valid1
4613 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4614 endtype, ncache + 2);
4615 /* Win if second argument is absolute. */
4616 if (valid1 == null_pointer_node)
4617 ret = valid0;
4618 /* Win if both arguments have the same relocation.
4619 Then the value is absolute. */
4620 else if (valid0 == valid1 && valid0 != 0)
4621 ret = null_pointer_node;
4622 /* Since GCC guarantees that string constants are unique in the
4623 generated code, a subtraction between two copies of the same
4624 constant string is absolute. */
4625 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4626 && valid1 && TREE_CODE (valid1) == STRING_CST
4627 && operand_equal_p (valid0, valid1, 1))
4628 ret = null_pointer_node;
4629 /* Support narrowing differences. */
4630 else
4631 ret = narrowing_initializer_constant_valid_p (value, endtype,
4632 ncache);
4634 else
4635 /* Support narrowing differences. */
4636 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4637 if (cache)
4639 cache[0] = value;
4640 cache[1] = ret;
4642 return ret;
4644 default:
4645 break;
4648 return NULL_TREE;
4651 /* Return nonzero if VALUE is a valid constant-valued expression
4652 for use in initializing a static variable; one that can be an
4653 element of a "constant" initializer.
4655 Return null_pointer_node if the value is absolute;
4656 if it is relocatable, return the variable that determines the relocation.
4657 We assume that VALUE has been folded as much as possible;
4658 therefore, we do not need to check for such things as
4659 arithmetic-combinations of integers. */
4660 tree
4661 initializer_constant_valid_p (tree value, tree endtype, bool reverse)
4663 tree reloc = initializer_constant_valid_p_1 (value, endtype, NULL);
4665 /* An absolute value is required with reverse storage order. */
4666 if (reloc
4667 && reloc != null_pointer_node
4668 && reverse
4669 && !AGGREGATE_TYPE_P (endtype)
4670 && !VECTOR_TYPE_P (endtype))
4671 reloc = NULL_TREE;
4673 return reloc;
4676 /* Return true if VALUE is a valid constant-valued expression
4677 for use in initializing a static bit-field; one that can be
4678 an element of a "constant" initializer. */
4680 bool
4681 initializer_constant_valid_for_bitfield_p (tree value)
4683 /* For bitfields we support integer constants or possibly nested aggregates
4684 of such. */
4685 switch (TREE_CODE (value))
4687 case CONSTRUCTOR:
4689 unsigned HOST_WIDE_INT idx;
4690 tree elt;
4692 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4693 if (!initializer_constant_valid_for_bitfield_p (elt))
4694 return false;
4695 return true;
4698 case INTEGER_CST:
4699 case REAL_CST:
4700 return true;
4702 case VIEW_CONVERT_EXPR:
4703 case NON_LVALUE_EXPR:
4704 return
4705 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4707 default:
4708 break;
4711 return false;
4714 /* output_constructor outer state of relevance in recursive calls, typically
4715 for nested aggregate bitfields. */
4717 struct oc_outer_state {
4718 unsigned int bit_offset; /* current position in ... */
4719 int byte; /* ... the outer byte buffer. */
4722 static unsigned HOST_WIDE_INT
4723 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int, bool,
4724 oc_outer_state *);
4726 /* Output assembler code for constant EXP, with no label.
4727 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4728 Assumes output_addressed_constants has been done on EXP already.
4730 Generate at least SIZE bytes of assembler data, padding at the end
4731 with zeros if necessary. SIZE must always be specified. The returned
4732 value is the actual number of bytes of assembler data generated, which
4733 may be bigger than SIZE if the object contains a variable length field.
4735 SIZE is important for structure constructors,
4736 since trailing members may have been omitted from the constructor.
4737 It is also important for initialization of arrays from string constants
4738 since the full length of the string constant might not be wanted.
4739 It is also needed for initialization of unions, where the initializer's
4740 type is just one member, and that may not be as long as the union.
4742 There a case in which we would fail to output exactly SIZE bytes:
4743 for a structure constructor that wants to produce more than SIZE bytes.
4744 But such constructors will never be generated for any possible input.
4746 ALIGN is the alignment of the data in bits.
4748 If REVERSE is true, EXP is output in reverse storage order. */
4750 static unsigned HOST_WIDE_INT
4751 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align,
4752 bool reverse)
4754 enum tree_code code;
4755 unsigned HOST_WIDE_INT thissize;
4756 rtx cst;
4758 if (size == 0 || flag_syntax_only)
4759 return size;
4761 /* See if we're trying to initialize a pointer in a non-default mode
4762 to the address of some declaration somewhere. If the target says
4763 the mode is valid for pointers, assume the target has a way of
4764 resolving it. */
4765 if (TREE_CODE (exp) == NOP_EXPR
4766 && POINTER_TYPE_P (TREE_TYPE (exp))
4767 && targetm.addr_space.valid_pointer_mode
4768 (TYPE_MODE (TREE_TYPE (exp)),
4769 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4771 tree saved_type = TREE_TYPE (exp);
4773 /* Peel off any intermediate conversions-to-pointer for valid
4774 pointer modes. */
4775 while (TREE_CODE (exp) == NOP_EXPR
4776 && POINTER_TYPE_P (TREE_TYPE (exp))
4777 && targetm.addr_space.valid_pointer_mode
4778 (TYPE_MODE (TREE_TYPE (exp)),
4779 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4780 exp = TREE_OPERAND (exp, 0);
4782 /* If what we're left with is the address of something, we can
4783 convert the address to the final type and output it that
4784 way. */
4785 if (TREE_CODE (exp) == ADDR_EXPR)
4786 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4787 /* Likewise for constant ints. */
4788 else if (TREE_CODE (exp) == INTEGER_CST)
4789 exp = fold_convert (saved_type, exp);
4793 /* Eliminate any conversions since we'll be outputting the underlying
4794 constant. */
4795 while (CONVERT_EXPR_P (exp)
4796 || TREE_CODE (exp) == NON_LVALUE_EXPR
4797 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4799 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4800 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4802 /* Make sure eliminating the conversion is really a no-op, except with
4803 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4804 union types to allow for Ada unchecked unions. */
4805 if (type_size > op_size
4806 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4807 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4808 /* Keep the conversion. */
4809 break;
4810 else
4811 exp = TREE_OPERAND (exp, 0);
4814 code = TREE_CODE (TREE_TYPE (exp));
4815 thissize = int_size_in_bytes (TREE_TYPE (exp));
4817 /* Allow a constructor with no elements for any data type.
4818 This means to fill the space with zeros. */
4819 if (TREE_CODE (exp) == CONSTRUCTOR
4820 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4822 assemble_zeros (size);
4823 return size;
4826 if (TREE_CODE (exp) == FDESC_EXPR)
4828 #ifdef ASM_OUTPUT_FDESC
4829 HOST_WIDE_INT part = tree_to_shwi (TREE_OPERAND (exp, 1));
4830 tree decl = TREE_OPERAND (exp, 0);
4831 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4832 #else
4833 gcc_unreachable ();
4834 #endif
4835 return size;
4838 /* Now output the underlying data. If we've handling the padding, return.
4839 Otherwise, break and ensure SIZE is the size written. */
4840 switch (code)
4842 case BOOLEAN_TYPE:
4843 case INTEGER_TYPE:
4844 case ENUMERAL_TYPE:
4845 case POINTER_TYPE:
4846 case REFERENCE_TYPE:
4847 case OFFSET_TYPE:
4848 case FIXED_POINT_TYPE:
4849 case POINTER_BOUNDS_TYPE:
4850 case NULLPTR_TYPE:
4851 cst = expand_expr (exp, NULL_RTX, VOIDmode, EXPAND_INITIALIZER);
4852 if (reverse)
4853 cst = flip_storage_order (TYPE_MODE (TREE_TYPE (exp)), cst);
4854 if (!assemble_integer (cst, MIN (size, thissize), align, 0))
4855 error ("initializer for integer/fixed-point value is too complicated");
4856 break;
4858 case REAL_TYPE:
4859 if (TREE_CODE (exp) != REAL_CST)
4860 error ("initializer for floating value is not a floating constant");
4861 else
4862 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)),
4863 align, reverse);
4864 break;
4866 case COMPLEX_TYPE:
4867 output_constant (TREE_REALPART (exp), thissize / 2, align, reverse);
4868 output_constant (TREE_IMAGPART (exp), thissize / 2,
4869 min_align (align, BITS_PER_UNIT * (thissize / 2)),
4870 reverse);
4871 break;
4873 case ARRAY_TYPE:
4874 case VECTOR_TYPE:
4875 switch (TREE_CODE (exp))
4877 case CONSTRUCTOR:
4878 return output_constructor (exp, size, align, reverse, NULL);
4879 case STRING_CST:
4880 thissize
4881 = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4882 assemble_string (TREE_STRING_POINTER (exp), thissize);
4883 break;
4884 case VECTOR_CST:
4886 machine_mode inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4887 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4888 int elt_size = GET_MODE_SIZE (inner);
4889 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align,
4890 reverse);
4891 thissize = elt_size;
4892 for (unsigned int i = 1; i < VECTOR_CST_NELTS (exp); i++)
4894 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign,
4895 reverse);
4896 thissize += elt_size;
4898 break;
4900 default:
4901 gcc_unreachable ();
4903 break;
4905 case RECORD_TYPE:
4906 case UNION_TYPE:
4907 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4908 return output_constructor (exp, size, align, reverse, NULL);
4910 case ERROR_MARK:
4911 return 0;
4913 default:
4914 gcc_unreachable ();
4917 if (size > thissize)
4918 assemble_zeros (size - thissize);
4920 return size;
4923 /* Subroutine of output_constructor, used for computing the size of
4924 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4925 type with an unspecified upper bound. */
4927 static unsigned HOST_WIDE_INT
4928 array_size_for_constructor (tree val)
4930 tree max_index;
4931 unsigned HOST_WIDE_INT cnt;
4932 tree index, value, tmp;
4933 offset_int i;
4935 /* This code used to attempt to handle string constants that are not
4936 arrays of single-bytes, but nothing else does, so there's no point in
4937 doing it here. */
4938 if (TREE_CODE (val) == STRING_CST)
4939 return TREE_STRING_LENGTH (val);
4941 max_index = NULL_TREE;
4942 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
4944 if (TREE_CODE (index) == RANGE_EXPR)
4945 index = TREE_OPERAND (index, 1);
4946 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
4947 max_index = index;
4950 if (max_index == NULL_TREE)
4951 return 0;
4953 /* Compute the total number of array elements. */
4954 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
4955 i = wi::to_offset (max_index) - wi::to_offset (tmp) + 1;
4957 /* Multiply by the array element unit size to find number of bytes. */
4958 i *= wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
4960 gcc_assert (wi::fits_uhwi_p (i));
4961 return i.to_uhwi ();
4964 /* Other datastructures + helpers for output_constructor. */
4966 /* output_constructor local state to support interaction with helpers. */
4968 struct oc_local_state {
4970 /* Received arguments. */
4971 tree exp; /* Constructor expression. */
4972 tree type; /* Type of constructor expression. */
4973 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */
4974 unsigned int align; /* Known initial alignment. */
4975 tree min_index; /* Lower bound if specified for an array. */
4977 /* Output processing state. */
4978 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */
4979 int byte; /* Part of a bitfield byte yet to be output. */
4980 int last_relative_index; /* Implicit or explicit index of the last
4981 array element output within a bitfield. */
4982 bool byte_buffer_in_use; /* Whether BYTE is in use. */
4983 bool reverse; /* Whether reverse storage order is in use. */
4985 /* Current element. */
4986 tree field; /* Current field decl in a record. */
4987 tree val; /* Current element value. */
4988 tree index; /* Current element index. */
4992 /* Helper for output_constructor. From the current LOCAL state, output a
4993 RANGE_EXPR element. */
4995 static void
4996 output_constructor_array_range (oc_local_state *local)
4998 unsigned HOST_WIDE_INT fieldsize
4999 = int_size_in_bytes (TREE_TYPE (local->type));
5001 HOST_WIDE_INT lo_index
5002 = tree_to_shwi (TREE_OPERAND (local->index, 0));
5003 HOST_WIDE_INT hi_index
5004 = tree_to_shwi (TREE_OPERAND (local->index, 1));
5005 HOST_WIDE_INT index;
5007 unsigned int align2
5008 = min_align (local->align, fieldsize * BITS_PER_UNIT);
5010 for (index = lo_index; index <= hi_index; index++)
5012 /* Output the element's initial value. */
5013 if (local->val == NULL_TREE)
5014 assemble_zeros (fieldsize);
5015 else
5016 fieldsize
5017 = output_constant (local->val, fieldsize, align2, local->reverse);
5019 /* Count its size. */
5020 local->total_bytes += fieldsize;
5024 /* Helper for output_constructor. From the current LOCAL state, output a
5025 field element that is not true bitfield or part of an outer one. */
5027 static void
5028 output_constructor_regular_field (oc_local_state *local)
5030 /* Field size and position. Since this structure is static, we know the
5031 positions are constant. */
5032 unsigned HOST_WIDE_INT fieldsize;
5033 HOST_WIDE_INT fieldpos;
5035 unsigned int align2;
5037 /* Output any buffered-up bit-fields preceding this element. */
5038 if (local->byte_buffer_in_use)
5040 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5041 local->total_bytes++;
5042 local->byte_buffer_in_use = false;
5045 if (local->index != NULL_TREE)
5047 /* Perform the index calculation in modulo arithmetic but
5048 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
5049 but we are using an unsigned sizetype. */
5050 unsigned prec = TYPE_PRECISION (sizetype);
5051 offset_int idx = wi::sext (wi::to_offset (local->index)
5052 - wi::to_offset (local->min_index), prec);
5053 fieldpos = (idx * wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (local->val))))
5054 .to_short_addr ();
5056 else if (local->field != NULL_TREE)
5057 fieldpos = int_byte_position (local->field);
5058 else
5059 fieldpos = 0;
5061 /* Advance to offset of this element.
5062 Note no alignment needed in an array, since that is guaranteed
5063 if each element has the proper size. */
5064 if (local->field != NULL_TREE || local->index != NULL_TREE)
5066 if (fieldpos > local->total_bytes)
5068 assemble_zeros (fieldpos - local->total_bytes);
5069 local->total_bytes = fieldpos;
5071 else
5072 /* Must not go backwards. */
5073 gcc_assert (fieldpos == local->total_bytes);
5076 /* Find the alignment of this element. */
5077 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
5079 /* Determine size this element should occupy. */
5080 if (local->field)
5082 fieldsize = 0;
5084 /* If this is an array with an unspecified upper bound,
5085 the initializer determines the size. */
5086 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
5087 but we cannot do this until the deprecated support for
5088 initializing zero-length array members is removed. */
5089 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
5090 && (!TYPE_DOMAIN (TREE_TYPE (local->field))
5091 || !TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field)))))
5093 fieldsize = array_size_for_constructor (local->val);
5094 /* Given a non-empty initialization, this field had better
5095 be last. Given a flexible array member, the next field
5096 on the chain is a TYPE_DECL of the enclosing struct. */
5097 const_tree next = DECL_CHAIN (local->field);
5098 gcc_assert (!fieldsize || !next || TREE_CODE (next) != FIELD_DECL);
5100 else
5101 fieldsize = tree_to_uhwi (DECL_SIZE_UNIT (local->field));
5103 else
5104 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
5106 /* Output the element's initial value. */
5107 if (local->val == NULL_TREE)
5108 assemble_zeros (fieldsize);
5109 else
5110 fieldsize
5111 = output_constant (local->val, fieldsize, align2, local->reverse);
5113 /* Count its size. */
5114 local->total_bytes += fieldsize;
5117 /* Helper for output_constructor. From the LOCAL state, output an element
5118 that is a true bitfield or part of an outer one. BIT_OFFSET is the offset
5119 from the start of a possibly ongoing outer byte buffer. */
5121 static void
5122 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
5124 /* Bit size of this element. */
5125 HOST_WIDE_INT ebitsize
5126 = (local->field
5127 ? tree_to_uhwi (DECL_SIZE (local->field))
5128 : tree_to_uhwi (TYPE_SIZE (TREE_TYPE (local->type))));
5130 /* Relative index of this element if this is an array component. */
5131 HOST_WIDE_INT relative_index
5132 = (!local->field
5133 ? (local->index
5134 ? (tree_to_shwi (local->index)
5135 - tree_to_shwi (local->min_index))
5136 : local->last_relative_index + 1)
5137 : 0);
5139 /* Bit position of this element from the start of the containing
5140 constructor. */
5141 HOST_WIDE_INT constructor_relative_ebitpos
5142 = (local->field
5143 ? int_bit_position (local->field)
5144 : ebitsize * relative_index);
5146 /* Bit position of this element from the start of a possibly ongoing
5147 outer byte buffer. */
5148 HOST_WIDE_INT byte_relative_ebitpos
5149 = bit_offset + constructor_relative_ebitpos;
5151 /* From the start of a possibly ongoing outer byte buffer, offsets to
5152 the first bit of this element and to the first bit past the end of
5153 this element. */
5154 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
5155 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
5157 local->last_relative_index = relative_index;
5159 if (local->val == NULL_TREE)
5160 local->val = integer_zero_node;
5162 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
5163 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
5164 local->val = TREE_OPERAND (local->val, 0);
5166 if (TREE_CODE (local->val) != INTEGER_CST
5167 && TREE_CODE (local->val) != CONSTRUCTOR)
5169 error ("invalid initial value for member %qE", DECL_NAME (local->field));
5170 return;
5173 /* If this field does not start in this (or next) byte, skip some bytes. */
5174 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5176 /* Output remnant of any bit field in previous bytes. */
5177 if (local->byte_buffer_in_use)
5179 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5180 local->total_bytes++;
5181 local->byte_buffer_in_use = false;
5184 /* If still not at proper byte, advance to there. */
5185 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5187 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
5188 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
5189 local->total_bytes = next_offset / BITS_PER_UNIT;
5193 /* Set up the buffer if necessary. */
5194 if (!local->byte_buffer_in_use)
5196 local->byte = 0;
5197 if (ebitsize > 0)
5198 local->byte_buffer_in_use = true;
5201 /* If this is nested constructor, recurse passing the bit offset and the
5202 pending data, then retrieve the new pending data afterwards. */
5203 if (TREE_CODE (local->val) == CONSTRUCTOR)
5205 oc_outer_state temp_state;
5206 temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5207 temp_state.byte = local->byte;
5208 local->total_bytes
5209 += output_constructor (local->val, 0, 0, local->reverse, &temp_state);
5210 local->byte = temp_state.byte;
5211 return;
5214 /* Otherwise, we must split the element into pieces that fall within
5215 separate bytes, and combine each byte with previous or following
5216 bit-fields. */
5217 while (next_offset < end_offset)
5219 int this_time;
5220 int shift;
5221 HOST_WIDE_INT value;
5222 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5223 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5225 /* Advance from byte to byte within this element when necessary. */
5226 while (next_byte != local->total_bytes)
5228 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5229 local->total_bytes++;
5230 local->byte = 0;
5233 /* Number of bits we can process at once (all part of the same byte). */
5234 this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5235 if (local->reverse ? !BYTES_BIG_ENDIAN : BYTES_BIG_ENDIAN)
5237 /* For big-endian data, take the most significant bits (of the
5238 bits that are significant) first and put them into bytes from
5239 the most significant end. */
5240 shift = end_offset - next_offset - this_time;
5242 /* Don't try to take a bunch of bits that cross
5243 the word boundary in the INTEGER_CST. We can
5244 only select bits from one element. */
5245 if ((shift / HOST_BITS_PER_WIDE_INT)
5246 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5248 const int end = shift + this_time - 1;
5249 shift = end & -HOST_BITS_PER_WIDE_INT;
5250 this_time = end - shift + 1;
5253 /* Now get the bits from the appropriate constant word. */
5254 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5255 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5257 /* Get the result. This works only when:
5258 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5259 local->byte |= (((value >> shift)
5260 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5261 << (BITS_PER_UNIT - this_time - next_bit));
5263 else
5265 /* On little-endian machines, take the least significant bits of
5266 the value first and pack them starting at the least significant
5267 bits of the bytes. */
5268 shift = next_offset - byte_relative_ebitpos;
5270 /* Don't try to take a bunch of bits that cross
5271 the word boundary in the INTEGER_CST. We can
5272 only select bits from one element. */
5273 if ((shift / HOST_BITS_PER_WIDE_INT)
5274 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5275 this_time
5276 = HOST_BITS_PER_WIDE_INT - (shift & (HOST_BITS_PER_WIDE_INT - 1));
5278 /* Now get the bits from the appropriate constant word. */
5279 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5280 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5282 /* Get the result. This works only when:
5283 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5284 local->byte |= (((value >> shift)
5285 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5286 << next_bit);
5289 next_offset += this_time;
5290 local->byte_buffer_in_use = true;
5294 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5295 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5296 caller output state of relevance in recursive invocations. */
5298 static unsigned HOST_WIDE_INT
5299 output_constructor (tree exp, unsigned HOST_WIDE_INT size, unsigned int align,
5300 bool reverse, oc_outer_state *outer)
5302 unsigned HOST_WIDE_INT cnt;
5303 constructor_elt *ce;
5304 oc_local_state local;
5306 /* Setup our local state to communicate with helpers. */
5307 local.exp = exp;
5308 local.type = TREE_TYPE (exp);
5309 local.size = size;
5310 local.align = align;
5311 if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5312 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5313 else
5314 local.min_index = integer_zero_node;
5316 local.total_bytes = 0;
5317 local.byte_buffer_in_use = outer != NULL;
5318 local.byte = outer ? outer->byte : 0;
5319 local.last_relative_index = -1;
5320 /* The storage order is specified for every aggregate type. */
5321 if (AGGREGATE_TYPE_P (local.type))
5322 local.reverse = TYPE_REVERSE_STORAGE_ORDER (local.type);
5323 else
5324 local.reverse = reverse;
5326 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5328 /* As CE goes through the elements of the constant, FIELD goes through the
5329 structure fields if the constant is a structure. If the constant is a
5330 union, we override this by getting the field from the TREE_LIST element.
5331 But the constant could also be an array. Then FIELD is zero.
5333 There is always a maximum of one element in the chain LINK for unions
5334 (even if the initializer in a source program incorrectly contains
5335 more one). */
5337 if (TREE_CODE (local.type) == RECORD_TYPE)
5338 local.field = TYPE_FIELDS (local.type);
5339 else
5340 local.field = NULL_TREE;
5342 for (cnt = 0;
5343 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5344 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5346 local.val = ce->value;
5347 local.index = NULL_TREE;
5349 /* The element in a union constructor specifies the proper field
5350 or index. */
5351 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5352 local.field = ce->index;
5354 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5355 local.index = ce->index;
5357 if (local.field && flag_verbose_asm)
5358 fprintf (asm_out_file, "%s %s:\n",
5359 ASM_COMMENT_START,
5360 DECL_NAME (local.field)
5361 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5362 : "<anonymous>");
5364 /* Eliminate the marker that makes a cast not be an lvalue. */
5365 if (local.val != NULL_TREE)
5366 STRIP_NOPS (local.val);
5368 /* Output the current element, using the appropriate helper ... */
5370 /* For an array slice not part of an outer bitfield. */
5371 if (!outer
5372 && local.index != NULL_TREE
5373 && TREE_CODE (local.index) == RANGE_EXPR)
5374 output_constructor_array_range (&local);
5376 /* For a field that is neither a true bitfield nor part of an outer one,
5377 known to be at least byte aligned and multiple-of-bytes long. */
5378 else if (!outer
5379 && (local.field == NULL_TREE
5380 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5381 output_constructor_regular_field (&local);
5383 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5384 supported for scalar fields, so we may need to convert first. */
5385 else
5387 if (TREE_CODE (local.val) == REAL_CST)
5388 local.val
5389 = fold_unary (VIEW_CONVERT_EXPR,
5390 build_nonstandard_integer_type
5391 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5392 local.val);
5393 output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5397 /* If we are not at toplevel, save the pending data for our caller.
5398 Otherwise output the pending data and padding zeros as needed. */
5399 if (outer)
5400 outer->byte = local.byte;
5401 else
5403 if (local.byte_buffer_in_use)
5405 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5406 local.total_bytes++;
5409 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5411 assemble_zeros (local.size - local.total_bytes);
5412 local.total_bytes = local.size;
5416 return local.total_bytes;
5419 /* Mark DECL as weak. */
5421 static void
5422 mark_weak (tree decl)
5424 if (DECL_WEAK (decl))
5425 return;
5427 struct symtab_node *n = symtab_node::get (decl);
5428 if (n && n->refuse_visibility_changes)
5429 error ("%+qD declared weak after being used", decl);
5430 DECL_WEAK (decl) = 1;
5432 if (DECL_RTL_SET_P (decl)
5433 && MEM_P (DECL_RTL (decl))
5434 && XEXP (DECL_RTL (decl), 0)
5435 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5436 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5439 /* Merge weak status between NEWDECL and OLDDECL. */
5441 void
5442 merge_weak (tree newdecl, tree olddecl)
5444 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5446 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5448 tree *pwd;
5449 /* We put the NEWDECL on the weak_decls list at some point
5450 and OLDDECL as well. Keep just OLDDECL on the list. */
5451 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5452 if (TREE_VALUE (*pwd) == newdecl)
5454 *pwd = TREE_CHAIN (*pwd);
5455 break;
5458 return;
5461 if (DECL_WEAK (newdecl))
5463 tree wd;
5465 /* NEWDECL is weak, but OLDDECL is not. */
5467 /* If we already output the OLDDECL, we're in trouble; we can't
5468 go back and make it weak. This should never happen in
5469 unit-at-a-time compilation. */
5470 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5472 /* If we've already generated rtl referencing OLDDECL, we may
5473 have done so in a way that will not function properly with
5474 a weak symbol. Again in unit-at-a-time this should be
5475 impossible. */
5476 gcc_assert (!TREE_USED (olddecl)
5477 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5479 /* PR 49899: You cannot convert a static function into a weak, public function. */
5480 if (! TREE_PUBLIC (olddecl) && TREE_PUBLIC (newdecl))
5481 error ("weak declaration of %q+D being applied to a already "
5482 "existing, static definition", newdecl);
5484 if (TARGET_SUPPORTS_WEAK)
5486 /* We put the NEWDECL on the weak_decls list at some point.
5487 Replace it with the OLDDECL. */
5488 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5489 if (TREE_VALUE (wd) == newdecl)
5491 TREE_VALUE (wd) = olddecl;
5492 break;
5494 /* We may not find the entry on the list. If NEWDECL is a
5495 weak alias, then we will have already called
5496 globalize_decl to remove the entry; in that case, we do
5497 not need to do anything. */
5500 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5501 mark_weak (olddecl);
5503 else
5504 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5505 weak. Just update NEWDECL to indicate that it's weak too. */
5506 mark_weak (newdecl);
5509 /* Declare DECL to be a weak symbol. */
5511 void
5512 declare_weak (tree decl)
5514 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5515 if (! TREE_PUBLIC (decl))
5517 error ("weak declaration of %q+D must be public", decl);
5518 return;
5520 else if (!TARGET_SUPPORTS_WEAK)
5521 warning (0, "weak declaration of %q+D not supported", decl);
5523 mark_weak (decl);
5524 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5525 DECL_ATTRIBUTES (decl)
5526 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5529 static void
5530 weak_finish_1 (tree decl)
5532 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5533 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5534 #endif
5536 if (! TREE_USED (decl))
5537 return;
5539 #ifdef ASM_WEAKEN_DECL
5540 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5541 #else
5542 #ifdef ASM_WEAKEN_LABEL
5543 ASM_WEAKEN_LABEL (asm_out_file, name);
5544 #else
5545 #ifdef ASM_OUTPUT_WEAK_ALIAS
5547 static bool warn_once = 0;
5548 if (! warn_once)
5550 warning (0, "only weak aliases are supported in this configuration");
5551 warn_once = 1;
5553 return;
5555 #endif
5556 #endif
5557 #endif
5560 /* Fiven an assembly name, find the decl it is associated with. */
5561 static tree
5562 find_decl (tree target)
5564 symtab_node *node = symtab_node::get_for_asmname (target);
5565 if (node)
5566 return node->decl;
5567 return NULL_TREE;
5570 /* This TREE_LIST contains weakref targets. */
5572 static GTY(()) tree weakref_targets;
5574 /* Emit any pending weak declarations. */
5576 void
5577 weak_finish (void)
5579 tree t;
5581 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5583 tree alias_decl = TREE_PURPOSE (t);
5584 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5586 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5587 /* Remove alias_decl from the weak list, but leave entries for
5588 the target alone. */
5589 target = NULL_TREE;
5590 #ifndef ASM_OUTPUT_WEAKREF
5591 else if (! TREE_SYMBOL_REFERENCED (target))
5593 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5594 defined, otherwise we and weak_finish_1 would use
5595 different macros. */
5596 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5597 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5598 # else
5599 tree decl = find_decl (target);
5601 if (! decl)
5603 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5604 TREE_CODE (alias_decl), target,
5605 TREE_TYPE (alias_decl));
5607 DECL_EXTERNAL (decl) = 1;
5608 TREE_PUBLIC (decl) = 1;
5609 DECL_ARTIFICIAL (decl) = 1;
5610 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5611 TREE_USED (decl) = 1;
5614 weak_finish_1 (decl);
5615 # endif
5617 #endif
5620 tree *p;
5621 tree t2;
5623 /* Remove the alias and the target from the pending weak list
5624 so that we do not emit any .weak directives for the former,
5625 nor multiple .weak directives for the latter. */
5626 for (p = &weak_decls; (t2 = *p) ; )
5628 if (TREE_VALUE (t2) == alias_decl
5629 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5630 *p = TREE_CHAIN (t2);
5631 else
5632 p = &TREE_CHAIN (t2);
5635 /* Remove other weakrefs to the same target, to speed things up. */
5636 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5638 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5639 *p = TREE_CHAIN (t2);
5640 else
5641 p = &TREE_CHAIN (t2);
5646 for (t = weak_decls; t; t = TREE_CHAIN (t))
5648 tree decl = TREE_VALUE (t);
5650 weak_finish_1 (decl);
5654 /* Emit the assembly bits to indicate that DECL is globally visible. */
5656 static void
5657 globalize_decl (tree decl)
5660 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5661 if (DECL_WEAK (decl))
5663 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5664 tree *p, t;
5666 #ifdef ASM_WEAKEN_DECL
5667 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5668 #else
5669 ASM_WEAKEN_LABEL (asm_out_file, name);
5670 #endif
5672 /* Remove this function from the pending weak list so that
5673 we do not emit multiple .weak directives for it. */
5674 for (p = &weak_decls; (t = *p) ; )
5676 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5677 *p = TREE_CHAIN (t);
5678 else
5679 p = &TREE_CHAIN (t);
5682 /* Remove weakrefs to the same target from the pending weakref
5683 list, for the same reason. */
5684 for (p = &weakref_targets; (t = *p) ; )
5686 if (DECL_ASSEMBLER_NAME (decl)
5687 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5688 *p = TREE_CHAIN (t);
5689 else
5690 p = &TREE_CHAIN (t);
5693 return;
5695 #endif
5697 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5700 vec<alias_pair, va_gc> *alias_pairs;
5702 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5703 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5704 tree node is DECL to have the value of the tree node TARGET. */
5706 void
5707 do_assemble_alias (tree decl, tree target)
5709 tree id;
5711 /* Emulated TLS had better not get this var. */
5712 gcc_assert (!(!targetm.have_tls
5713 && VAR_P (decl)
5714 && DECL_THREAD_LOCAL_P (decl)));
5716 if (TREE_ASM_WRITTEN (decl))
5717 return;
5719 id = DECL_ASSEMBLER_NAME (decl);
5720 ultimate_transparent_alias_target (&id);
5721 ultimate_transparent_alias_target (&target);
5723 /* We must force creation of DECL_RTL for debug info generation, even though
5724 we don't use it here. */
5725 make_decl_rtl (decl);
5727 TREE_ASM_WRITTEN (decl) = 1;
5728 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5729 TREE_ASM_WRITTEN (id) = 1;
5731 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5733 if (!TREE_SYMBOL_REFERENCED (target))
5734 weakref_targets = tree_cons (decl, target, weakref_targets);
5736 #ifdef ASM_OUTPUT_WEAKREF
5737 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5738 IDENTIFIER_POINTER (id),
5739 IDENTIFIER_POINTER (target));
5740 #else
5741 if (!TARGET_SUPPORTS_WEAK)
5743 error_at (DECL_SOURCE_LOCATION (decl),
5744 "weakref is not supported in this configuration");
5745 return;
5747 #endif
5748 return;
5751 #ifdef ASM_OUTPUT_DEF
5752 tree orig_decl = decl;
5754 if (TREE_CODE (decl) == FUNCTION_DECL
5755 && cgraph_node::get (decl)->instrumentation_clone
5756 && cgraph_node::get (decl)->instrumented_version)
5757 orig_decl = cgraph_node::get (decl)->instrumented_version->decl;
5759 /* Make name accessible from other files, if appropriate. */
5761 if (TREE_PUBLIC (decl) || TREE_PUBLIC (orig_decl))
5763 globalize_decl (decl);
5764 maybe_assemble_visibility (decl);
5766 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5768 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5769 if (targetm.has_ifunc_p ())
5770 ASM_OUTPUT_TYPE_DIRECTIVE
5771 (asm_out_file, IDENTIFIER_POINTER (id),
5772 IFUNC_ASM_TYPE);
5773 else
5774 #endif
5775 error_at (DECL_SOURCE_LOCATION (decl),
5776 "ifunc is not supported on this target");
5779 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5780 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5781 # else
5782 ASM_OUTPUT_DEF (asm_out_file,
5783 IDENTIFIER_POINTER (id),
5784 IDENTIFIER_POINTER (target));
5785 # endif
5786 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5788 const char *name;
5789 tree *p, t;
5791 name = IDENTIFIER_POINTER (id);
5792 # ifdef ASM_WEAKEN_DECL
5793 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5794 # else
5795 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5796 # endif
5797 /* Remove this function from the pending weak list so that
5798 we do not emit multiple .weak directives for it. */
5799 for (p = &weak_decls; (t = *p) ; )
5800 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t))
5801 || id == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5802 *p = TREE_CHAIN (t);
5803 else
5804 p = &TREE_CHAIN (t);
5806 /* Remove weakrefs to the same target from the pending weakref
5807 list, for the same reason. */
5808 for (p = &weakref_targets; (t = *p) ; )
5810 if (id == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5811 *p = TREE_CHAIN (t);
5812 else
5813 p = &TREE_CHAIN (t);
5816 #endif
5819 /* Emit an assembler directive to make the symbol for DECL an alias to
5820 the symbol for TARGET. */
5822 void
5823 assemble_alias (tree decl, tree target)
5825 tree target_decl;
5827 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5829 tree alias = DECL_ASSEMBLER_NAME (decl);
5831 ultimate_transparent_alias_target (&target);
5833 if (alias == target)
5834 error ("weakref %q+D ultimately targets itself", decl);
5835 if (TREE_PUBLIC (decl))
5836 error ("weakref %q+D must have static linkage", decl);
5838 else
5840 #if !defined (ASM_OUTPUT_DEF)
5841 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5842 error_at (DECL_SOURCE_LOCATION (decl),
5843 "alias definitions not supported in this configuration");
5844 TREE_ASM_WRITTEN (decl) = 1;
5845 return;
5846 # else
5847 if (!DECL_WEAK (decl))
5849 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5850 error_at (DECL_SOURCE_LOCATION (decl),
5851 "ifunc is not supported in this configuration");
5852 else
5853 error_at (DECL_SOURCE_LOCATION (decl),
5854 "only weak aliases are supported in this configuration");
5855 TREE_ASM_WRITTEN (decl) = 1;
5856 return;
5858 # endif
5859 #endif
5861 TREE_USED (decl) = 1;
5863 /* Allow aliases to aliases. */
5864 if (TREE_CODE (decl) == FUNCTION_DECL)
5865 cgraph_node::get_create (decl)->alias = true;
5866 else
5867 varpool_node::get_create (decl)->alias = true;
5869 /* If the target has already been emitted, we don't have to queue the
5870 alias. This saves a tad of memory. */
5871 if (symtab->global_info_ready)
5872 target_decl = find_decl (target);
5873 else
5874 target_decl= NULL;
5875 if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5876 || symtab->state >= EXPANSION)
5877 do_assemble_alias (decl, target);
5878 else
5880 alias_pair p = {decl, target};
5881 vec_safe_push (alias_pairs, p);
5885 /* Record and output a table of translations from original function
5886 to its transaction aware clone. Note that tm_pure functions are
5887 considered to be their own clone. */
5889 struct tm_clone_hasher : ggc_cache_ptr_hash<tree_map>
5891 static hashval_t hash (tree_map *m) { return tree_map_hash (m); }
5892 static bool equal (tree_map *a, tree_map *b) { return tree_map_eq (a, b); }
5894 static int
5895 keep_cache_entry (tree_map *&e)
5897 return ggc_marked_p (e->base.from);
5901 static GTY((cache)) hash_table<tm_clone_hasher> *tm_clone_hash;
5903 void
5904 record_tm_clone_pair (tree o, tree n)
5906 struct tree_map **slot, *h;
5908 if (tm_clone_hash == NULL)
5909 tm_clone_hash = hash_table<tm_clone_hasher>::create_ggc (32);
5911 h = ggc_alloc<tree_map> ();
5912 h->hash = htab_hash_pointer (o);
5913 h->base.from = o;
5914 h->to = n;
5916 slot = tm_clone_hash->find_slot_with_hash (h, h->hash, INSERT);
5917 *slot = h;
5920 tree
5921 get_tm_clone_pair (tree o)
5923 if (tm_clone_hash)
5925 struct tree_map *h, in;
5927 in.base.from = o;
5928 in.hash = htab_hash_pointer (o);
5929 h = tm_clone_hash->find_with_hash (&in, in.hash);
5930 if (h)
5931 return h->to;
5933 return NULL_TREE;
5936 struct tm_alias_pair
5938 unsigned int uid;
5939 tree from;
5940 tree to;
5944 /* Dump the actual pairs to the .tm_clone_table section. */
5946 static void
5947 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
5949 unsigned i;
5950 tm_alias_pair *p;
5951 bool switched = false;
5953 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
5955 tree src = p->from;
5956 tree dst = p->to;
5957 struct cgraph_node *src_n = cgraph_node::get (src);
5958 struct cgraph_node *dst_n = cgraph_node::get (dst);
5960 /* The function ipa_tm_create_version() marks the clone as needed if
5961 the original function was needed. But we also mark the clone as
5962 needed if we ever called the clone indirectly through
5963 TM_GETTMCLONE. If neither of these are true, we didn't generate
5964 a clone, and we didn't call it indirectly... no sense keeping it
5965 in the clone table. */
5966 if (!dst_n || !dst_n->definition)
5967 continue;
5969 /* This covers the case where we have optimized the original
5970 function away, and only access the transactional clone. */
5971 if (!src_n || !src_n->definition)
5972 continue;
5974 if (!switched)
5976 switch_to_section (targetm.asm_out.tm_clone_table_section ());
5977 assemble_align (POINTER_SIZE);
5978 switched = true;
5981 assemble_integer (XEXP (DECL_RTL (src), 0),
5982 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
5983 assemble_integer (XEXP (DECL_RTL (dst), 0),
5984 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
5988 /* Provide a default for the tm_clone_table section. */
5990 section *
5991 default_clone_table_section (void)
5993 return get_named_section (NULL, ".tm_clone_table", 3);
5996 /* Helper comparison function for qsorting by the DECL_UID stored in
5997 alias_pair->emitted_diags. */
5999 static int
6000 tm_alias_pair_cmp (const void *x, const void *y)
6002 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
6003 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
6004 if (p1->uid < p2->uid)
6005 return -1;
6006 if (p1->uid > p2->uid)
6007 return 1;
6008 return 0;
6011 void
6012 finish_tm_clone_pairs (void)
6014 vec<tm_alias_pair> tm_alias_pairs = vNULL;
6016 if (tm_clone_hash == NULL)
6017 return;
6019 /* We need a determenistic order for the .tm_clone_table, otherwise
6020 we will get bootstrap comparison failures, so dump the hash table
6021 to a vector, sort it, and dump the vector. */
6023 /* Dump the hashtable to a vector. */
6024 tree_map *map;
6025 hash_table<tm_clone_hasher>::iterator iter;
6026 FOR_EACH_HASH_TABLE_ELEMENT (*tm_clone_hash, map, tree_map *, iter)
6028 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
6029 tm_alias_pairs.safe_push (p);
6031 /* Sort it. */
6032 tm_alias_pairs.qsort (tm_alias_pair_cmp);
6034 /* Dump it. */
6035 dump_tm_clone_pairs (tm_alias_pairs);
6037 tm_clone_hash->empty ();
6038 tm_clone_hash = NULL;
6039 tm_alias_pairs.release ();
6043 /* Emit an assembler directive to set symbol for DECL visibility to
6044 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
6046 void
6047 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
6048 int vis ATTRIBUTE_UNUSED)
6050 #ifdef HAVE_GAS_HIDDEN
6051 static const char * const visibility_types[] = {
6052 NULL, "protected", "hidden", "internal"
6055 const char *name, *type;
6056 tree id;
6058 id = DECL_ASSEMBLER_NAME (decl);
6059 ultimate_transparent_alias_target (&id);
6060 name = IDENTIFIER_POINTER (id);
6062 type = visibility_types[vis];
6064 fprintf (asm_out_file, "\t.%s\t", type);
6065 assemble_name (asm_out_file, name);
6066 fprintf (asm_out_file, "\n");
6067 #else
6068 if (!DECL_ARTIFICIAL (decl))
6069 warning (OPT_Wattributes, "visibility attribute not supported "
6070 "in this configuration; ignored");
6071 #endif
6074 /* A helper function to call assemble_visibility when needed for a decl. */
6077 maybe_assemble_visibility (tree decl)
6079 enum symbol_visibility vis = DECL_VISIBILITY (decl);
6081 if (TREE_CODE (decl) == FUNCTION_DECL
6082 && cgraph_node::get (decl)
6083 && cgraph_node::get (decl)->instrumentation_clone
6084 && cgraph_node::get (decl)->instrumented_version)
6085 vis = DECL_VISIBILITY (cgraph_node::get (decl)->instrumented_version->decl);
6087 if (vis != VISIBILITY_DEFAULT)
6089 targetm.asm_out.assemble_visibility (decl, vis);
6090 return 1;
6092 else
6093 return 0;
6096 /* Returns 1 if the target configuration supports defining public symbols
6097 so that one of them will be chosen at link time instead of generating a
6098 multiply-defined symbol error, whether through the use of weak symbols or
6099 a target-specific mechanism for having duplicates discarded. */
6102 supports_one_only (void)
6104 if (SUPPORTS_ONE_ONLY)
6105 return 1;
6106 return TARGET_SUPPORTS_WEAK;
6109 /* Set up DECL as a public symbol that can be defined in multiple
6110 translation units without generating a linker error. */
6112 void
6113 make_decl_one_only (tree decl, tree comdat_group)
6115 struct symtab_node *symbol;
6116 gcc_assert (VAR_OR_FUNCTION_DECL_P (decl));
6118 TREE_PUBLIC (decl) = 1;
6120 if (VAR_P (decl))
6121 symbol = varpool_node::get_create (decl);
6122 else
6123 symbol = cgraph_node::get_create (decl);
6125 if (SUPPORTS_ONE_ONLY)
6127 #ifdef MAKE_DECL_ONE_ONLY
6128 MAKE_DECL_ONE_ONLY (decl);
6129 #endif
6130 symbol->set_comdat_group (comdat_group);
6132 else if (VAR_P (decl)
6133 && (DECL_INITIAL (decl) == 0
6134 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
6135 DECL_COMMON (decl) = 1;
6136 else
6138 gcc_assert (TARGET_SUPPORTS_WEAK);
6139 DECL_WEAK (decl) = 1;
6143 void
6144 init_varasm_once (void)
6146 section_htab = hash_table<section_hasher>::create_ggc (31);
6147 object_block_htab = hash_table<object_block_hasher>::create_ggc (31);
6148 const_desc_htab = hash_table<tree_descriptor_hasher>::create_ggc (1009);
6150 shared_constant_pool = create_constant_pool ();
6152 #ifdef TEXT_SECTION_ASM_OP
6153 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
6154 TEXT_SECTION_ASM_OP);
6155 #endif
6157 #ifdef DATA_SECTION_ASM_OP
6158 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
6159 DATA_SECTION_ASM_OP);
6160 #endif
6162 #ifdef SDATA_SECTION_ASM_OP
6163 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
6164 SDATA_SECTION_ASM_OP);
6165 #endif
6167 #ifdef READONLY_DATA_SECTION_ASM_OP
6168 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
6169 READONLY_DATA_SECTION_ASM_OP);
6170 #endif
6172 #ifdef CTORS_SECTION_ASM_OP
6173 ctors_section = get_unnamed_section (0, output_section_asm_op,
6174 CTORS_SECTION_ASM_OP);
6175 #endif
6177 #ifdef DTORS_SECTION_ASM_OP
6178 dtors_section = get_unnamed_section (0, output_section_asm_op,
6179 DTORS_SECTION_ASM_OP);
6180 #endif
6182 #ifdef BSS_SECTION_ASM_OP
6183 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6184 output_section_asm_op,
6185 BSS_SECTION_ASM_OP);
6186 #endif
6188 #ifdef SBSS_SECTION_ASM_OP
6189 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6190 output_section_asm_op,
6191 SBSS_SECTION_ASM_OP);
6192 #endif
6194 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6195 | SECTION_COMMON, emit_tls_common);
6196 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6197 | SECTION_COMMON, emit_local);
6198 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6199 | SECTION_COMMON, emit_common);
6201 #if defined ASM_OUTPUT_ALIGNED_BSS
6202 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
6203 emit_bss);
6204 #endif
6206 targetm.asm_out.init_sections ();
6208 if (readonly_data_section == NULL)
6209 readonly_data_section = text_section;
6211 #ifdef ASM_OUTPUT_EXTERNAL
6212 pending_assemble_externals_set = new hash_set<tree>;
6213 #endif
6216 enum tls_model
6217 decl_default_tls_model (const_tree decl)
6219 enum tls_model kind;
6220 bool is_local;
6222 is_local = targetm.binds_local_p (decl);
6223 if (!flag_shlib)
6225 if (is_local)
6226 kind = TLS_MODEL_LOCAL_EXEC;
6227 else
6228 kind = TLS_MODEL_INITIAL_EXEC;
6231 /* Local dynamic is inefficient when we're not combining the
6232 parts of the address. */
6233 else if (optimize && is_local)
6234 kind = TLS_MODEL_LOCAL_DYNAMIC;
6235 else
6236 kind = TLS_MODEL_GLOBAL_DYNAMIC;
6237 if (kind < flag_tls_default)
6238 kind = flag_tls_default;
6240 return kind;
6243 /* Select a set of attributes for section NAME based on the properties
6244 of DECL and whether or not RELOC indicates that DECL's initializer
6245 might contain runtime relocations.
6247 We make the section read-only and executable for a function decl,
6248 read-only for a const data decl, and writable for a non-const data decl. */
6250 unsigned int
6251 default_section_type_flags (tree decl, const char *name, int reloc)
6253 unsigned int flags;
6255 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6256 flags = SECTION_CODE;
6257 else if (decl)
6259 enum section_category category
6260 = categorize_decl_for_section (decl, reloc);
6261 if (decl_readonly_section_1 (category))
6262 flags = 0;
6263 else if (category == SECCAT_DATA_REL_RO
6264 || category == SECCAT_DATA_REL_RO_LOCAL)
6265 flags = SECTION_WRITE | SECTION_RELRO;
6266 else
6267 flags = SECTION_WRITE;
6269 else
6271 flags = SECTION_WRITE;
6272 if (strcmp (name, ".data.rel.ro") == 0
6273 || strcmp (name, ".data.rel.ro.local") == 0)
6274 flags |= SECTION_RELRO;
6277 if (decl && DECL_P (decl) && DECL_COMDAT_GROUP (decl))
6278 flags |= SECTION_LINKONCE;
6280 if (strcmp (name, ".vtable_map_vars") == 0)
6281 flags |= SECTION_LINKONCE;
6283 if (decl && VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6284 flags |= SECTION_TLS | SECTION_WRITE;
6286 if (strcmp (name, ".bss") == 0
6287 || strncmp (name, ".bss.", 5) == 0
6288 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6289 || strcmp (name, ".persistent.bss") == 0
6290 || strcmp (name, ".sbss") == 0
6291 || strncmp (name, ".sbss.", 6) == 0
6292 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6293 flags |= SECTION_BSS;
6295 if (strcmp (name, ".tdata") == 0
6296 || strncmp (name, ".tdata.", 7) == 0
6297 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6298 flags |= SECTION_TLS;
6300 if (strcmp (name, ".tbss") == 0
6301 || strncmp (name, ".tbss.", 6) == 0
6302 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6303 flags |= SECTION_TLS | SECTION_BSS;
6305 /* These three sections have special ELF types. They are neither
6306 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
6307 want to print a section type (@progbits or @nobits). If someone
6308 is silly enough to emit code or TLS variables to one of these
6309 sections, then don't handle them specially. */
6310 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6311 && (strcmp (name, ".init_array") == 0
6312 || strcmp (name, ".fini_array") == 0
6313 || strcmp (name, ".preinit_array") == 0))
6314 flags |= SECTION_NOTYPE;
6316 return flags;
6319 /* Return true if the target supports some form of global BSS,
6320 either through bss_noswitch_section, or by selecting a BSS
6321 section in TARGET_ASM_SELECT_SECTION. */
6323 bool
6324 have_global_bss_p (void)
6326 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6329 /* Output assembly to switch to section NAME with attribute FLAGS.
6330 Four variants for common object file formats. */
6332 void
6333 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6334 unsigned int flags ATTRIBUTE_UNUSED,
6335 tree decl ATTRIBUTE_UNUSED)
6337 /* Some object formats don't support named sections at all. The
6338 front-end should already have flagged this as an error. */
6339 gcc_unreachable ();
6342 #ifndef TLS_SECTION_ASM_FLAG
6343 #define TLS_SECTION_ASM_FLAG 'T'
6344 #endif
6346 void
6347 default_elf_asm_named_section (const char *name, unsigned int flags,
6348 tree decl)
6350 char flagchars[11], *f = flagchars;
6351 unsigned int numeric_value = 0;
6353 /* If we have already declared this section, we can use an
6354 abbreviated form to switch back to it -- unless this section is
6355 part of a COMDAT groups, in which case GAS requires the full
6356 declaration every time. */
6357 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6358 && (flags & SECTION_DECLARED))
6360 fprintf (asm_out_file, "\t.section\t%s\n", name);
6361 return;
6364 /* If we have a machine specific flag, then use the numeric value to pass
6365 this on to GAS. */
6366 if (targetm.asm_out.elf_flags_numeric (flags, &numeric_value))
6367 snprintf (f, sizeof (flagchars), "0x%08x", numeric_value);
6368 else
6370 if (!(flags & SECTION_DEBUG))
6371 *f++ = 'a';
6372 #if defined (HAVE_GAS_SECTION_EXCLUDE) && HAVE_GAS_SECTION_EXCLUDE == 1
6373 if (flags & SECTION_EXCLUDE)
6374 *f++ = 'e';
6375 #endif
6376 if (flags & SECTION_WRITE)
6377 *f++ = 'w';
6378 if (flags & SECTION_CODE)
6379 *f++ = 'x';
6380 if (flags & SECTION_SMALL)
6381 *f++ = 's';
6382 if (flags & SECTION_MERGE)
6383 *f++ = 'M';
6384 if (flags & SECTION_STRINGS)
6385 *f++ = 'S';
6386 if (flags & SECTION_TLS)
6387 *f++ = TLS_SECTION_ASM_FLAG;
6388 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6389 *f++ = 'G';
6390 #ifdef MACH_DEP_SECTION_ASM_FLAG
6391 if (flags & SECTION_MACH_DEP)
6392 *f++ = MACH_DEP_SECTION_ASM_FLAG;
6393 #endif
6394 *f = '\0';
6397 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6399 if (!(flags & SECTION_NOTYPE))
6401 const char *type;
6402 const char *format;
6404 if (flags & SECTION_BSS)
6405 type = "nobits";
6406 else
6407 type = "progbits";
6409 format = ",@%s";
6410 /* On platforms that use "@" as the assembly comment character,
6411 use "%" instead. */
6412 if (strcmp (ASM_COMMENT_START, "@") == 0)
6413 format = ",%%%s";
6414 fprintf (asm_out_file, format, type);
6416 if (flags & SECTION_ENTSIZE)
6417 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6418 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6420 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6421 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6422 else
6423 fprintf (asm_out_file, ",%s,comdat",
6424 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6428 putc ('\n', asm_out_file);
6431 void
6432 default_coff_asm_named_section (const char *name, unsigned int flags,
6433 tree decl ATTRIBUTE_UNUSED)
6435 char flagchars[8], *f = flagchars;
6437 if (flags & SECTION_WRITE)
6438 *f++ = 'w';
6439 if (flags & SECTION_CODE)
6440 *f++ = 'x';
6441 *f = '\0';
6443 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6446 void
6447 default_pe_asm_named_section (const char *name, unsigned int flags,
6448 tree decl)
6450 default_coff_asm_named_section (name, flags, decl);
6452 if (flags & SECTION_LINKONCE)
6454 /* Functions may have been compiled at various levels of
6455 optimization so we can't use `same_size' here.
6456 Instead, have the linker pick one. */
6457 fprintf (asm_out_file, "\t.linkonce %s\n",
6458 (flags & SECTION_CODE ? "discard" : "same_size"));
6462 /* The lame default section selector. */
6464 section *
6465 default_select_section (tree decl, int reloc,
6466 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6468 if (DECL_P (decl))
6470 if (decl_readonly_section (decl, reloc))
6471 return readonly_data_section;
6473 else if (TREE_CODE (decl) == CONSTRUCTOR)
6475 if (! ((flag_pic && reloc)
6476 || !TREE_READONLY (decl)
6477 || TREE_SIDE_EFFECTS (decl)
6478 || !TREE_CONSTANT (decl)))
6479 return readonly_data_section;
6481 else if (TREE_CODE (decl) == STRING_CST)
6482 return readonly_data_section;
6483 else if (! (flag_pic && reloc))
6484 return readonly_data_section;
6486 return data_section;
6489 enum section_category
6490 categorize_decl_for_section (const_tree decl, int reloc)
6492 enum section_category ret;
6494 if (TREE_CODE (decl) == FUNCTION_DECL)
6495 return SECCAT_TEXT;
6496 else if (TREE_CODE (decl) == STRING_CST)
6498 if ((flag_sanitize & SANITIZE_ADDRESS)
6499 && asan_protect_global (CONST_CAST_TREE (decl)))
6500 /* or !flag_merge_constants */
6501 return SECCAT_RODATA;
6502 else
6503 return SECCAT_RODATA_MERGE_STR;
6505 else if (VAR_P (decl))
6507 if (bss_initializer_p (decl))
6508 ret = SECCAT_BSS;
6509 else if (! TREE_READONLY (decl)
6510 || TREE_SIDE_EFFECTS (decl)
6511 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
6513 /* Here the reloc_rw_mask is not testing whether the section should
6514 be read-only or not, but whether the dynamic link will have to
6515 do something. If so, we wish to segregate the data in order to
6516 minimize cache misses inside the dynamic linker. */
6517 if (reloc & targetm.asm_out.reloc_rw_mask ())
6518 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6519 else
6520 ret = SECCAT_DATA;
6522 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6523 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6524 else if (reloc || flag_merge_constants < 2
6525 || ((flag_sanitize & SANITIZE_ADDRESS)
6526 && asan_protect_global (CONST_CAST_TREE (decl))))
6527 /* C and C++ don't allow different variables to share the same
6528 location. -fmerge-all-constants allows even that (at the
6529 expense of not conforming). */
6530 ret = SECCAT_RODATA;
6531 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6532 ret = SECCAT_RODATA_MERGE_STR_INIT;
6533 else
6534 ret = SECCAT_RODATA_MERGE_CONST;
6536 else if (TREE_CODE (decl) == CONSTRUCTOR)
6538 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6539 || TREE_SIDE_EFFECTS (decl)
6540 || ! TREE_CONSTANT (decl))
6541 ret = SECCAT_DATA;
6542 else
6543 ret = SECCAT_RODATA;
6545 else
6546 ret = SECCAT_RODATA;
6548 /* There are no read-only thread-local sections. */
6549 if (VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6551 /* Note that this would be *just* SECCAT_BSS, except that there's
6552 no concept of a read-only thread-local-data section. */
6553 if (ret == SECCAT_BSS
6554 || (flag_zero_initialized_in_bss
6555 && initializer_zerop (DECL_INITIAL (decl))))
6556 ret = SECCAT_TBSS;
6557 else
6558 ret = SECCAT_TDATA;
6561 /* If the target uses small data sections, select it. */
6562 else if (targetm.in_small_data_p (decl))
6564 if (ret == SECCAT_BSS)
6565 ret = SECCAT_SBSS;
6566 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6567 ret = SECCAT_SRODATA;
6568 else
6569 ret = SECCAT_SDATA;
6572 return ret;
6575 static bool
6576 decl_readonly_section_1 (enum section_category category)
6578 switch (category)
6580 case SECCAT_RODATA:
6581 case SECCAT_RODATA_MERGE_STR:
6582 case SECCAT_RODATA_MERGE_STR_INIT:
6583 case SECCAT_RODATA_MERGE_CONST:
6584 case SECCAT_SRODATA:
6585 return true;
6586 default:
6587 return false;
6591 bool
6592 decl_readonly_section (const_tree decl, int reloc)
6594 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6597 /* Select a section based on the above categorization. */
6599 section *
6600 default_elf_select_section (tree decl, int reloc,
6601 unsigned HOST_WIDE_INT align)
6603 const char *sname;
6604 switch (categorize_decl_for_section (decl, reloc))
6606 case SECCAT_TEXT:
6607 /* We're not supposed to be called on FUNCTION_DECLs. */
6608 gcc_unreachable ();
6609 case SECCAT_RODATA:
6610 return readonly_data_section;
6611 case SECCAT_RODATA_MERGE_STR:
6612 return mergeable_string_section (decl, align, 0);
6613 case SECCAT_RODATA_MERGE_STR_INIT:
6614 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6615 case SECCAT_RODATA_MERGE_CONST:
6616 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6617 case SECCAT_SRODATA:
6618 sname = ".sdata2";
6619 break;
6620 case SECCAT_DATA:
6621 return data_section;
6622 case SECCAT_DATA_REL:
6623 sname = ".data.rel";
6624 break;
6625 case SECCAT_DATA_REL_LOCAL:
6626 sname = ".data.rel.local";
6627 break;
6628 case SECCAT_DATA_REL_RO:
6629 sname = ".data.rel.ro";
6630 break;
6631 case SECCAT_DATA_REL_RO_LOCAL:
6632 sname = ".data.rel.ro.local";
6633 break;
6634 case SECCAT_SDATA:
6635 sname = ".sdata";
6636 break;
6637 case SECCAT_TDATA:
6638 sname = ".tdata";
6639 break;
6640 case SECCAT_BSS:
6641 if (bss_section)
6642 return bss_section;
6643 sname = ".bss";
6644 break;
6645 case SECCAT_SBSS:
6646 sname = ".sbss";
6647 break;
6648 case SECCAT_TBSS:
6649 sname = ".tbss";
6650 break;
6651 default:
6652 gcc_unreachable ();
6655 return get_named_section (decl, sname, reloc);
6658 /* Construct a unique section name based on the decl name and the
6659 categorization performed above. */
6661 void
6662 default_unique_section (tree decl, int reloc)
6664 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6665 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6666 const char *prefix, *name, *linkonce;
6667 char *string;
6668 tree id;
6670 switch (categorize_decl_for_section (decl, reloc))
6672 case SECCAT_TEXT:
6673 prefix = one_only ? ".t" : ".text";
6674 break;
6675 case SECCAT_RODATA:
6676 case SECCAT_RODATA_MERGE_STR:
6677 case SECCAT_RODATA_MERGE_STR_INIT:
6678 case SECCAT_RODATA_MERGE_CONST:
6679 prefix = one_only ? ".r" : ".rodata";
6680 break;
6681 case SECCAT_SRODATA:
6682 prefix = one_only ? ".s2" : ".sdata2";
6683 break;
6684 case SECCAT_DATA:
6685 prefix = one_only ? ".d" : ".data";
6686 break;
6687 case SECCAT_DATA_REL:
6688 prefix = one_only ? ".d.rel" : ".data.rel";
6689 break;
6690 case SECCAT_DATA_REL_LOCAL:
6691 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6692 break;
6693 case SECCAT_DATA_REL_RO:
6694 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6695 break;
6696 case SECCAT_DATA_REL_RO_LOCAL:
6697 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6698 break;
6699 case SECCAT_SDATA:
6700 prefix = one_only ? ".s" : ".sdata";
6701 break;
6702 case SECCAT_BSS:
6703 prefix = one_only ? ".b" : ".bss";
6704 break;
6705 case SECCAT_SBSS:
6706 prefix = one_only ? ".sb" : ".sbss";
6707 break;
6708 case SECCAT_TDATA:
6709 prefix = one_only ? ".td" : ".tdata";
6710 break;
6711 case SECCAT_TBSS:
6712 prefix = one_only ? ".tb" : ".tbss";
6713 break;
6714 default:
6715 gcc_unreachable ();
6718 id = DECL_ASSEMBLER_NAME (decl);
6719 ultimate_transparent_alias_target (&id);
6720 name = IDENTIFIER_POINTER (id);
6721 name = targetm.strip_name_encoding (name);
6723 /* If we're using one_only, then there needs to be a .gnu.linkonce
6724 prefix to the section name. */
6725 linkonce = one_only ? ".gnu.linkonce" : "";
6727 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6729 set_decl_section_name (decl, string);
6732 /* Subroutine of compute_reloc_for_rtx for leaf rtxes. */
6734 static int
6735 compute_reloc_for_rtx_1 (const_rtx x)
6737 switch (GET_CODE (x))
6739 case SYMBOL_REF:
6740 return SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6741 case LABEL_REF:
6742 return 1;
6743 default:
6744 return 0;
6748 /* Like compute_reloc_for_constant, except for an RTX. The return value
6749 is a mask for which bit 1 indicates a global relocation, and bit 0
6750 indicates a local relocation. */
6752 static int
6753 compute_reloc_for_rtx (const_rtx x)
6755 switch (GET_CODE (x))
6757 case SYMBOL_REF:
6758 case LABEL_REF:
6759 return compute_reloc_for_rtx_1 (x);
6761 case CONST:
6763 int reloc = 0;
6764 subrtx_iterator::array_type array;
6765 FOR_EACH_SUBRTX (iter, array, x, ALL)
6766 reloc |= compute_reloc_for_rtx_1 (*iter);
6767 return reloc;
6770 default:
6771 return 0;
6775 section *
6776 default_select_rtx_section (machine_mode mode ATTRIBUTE_UNUSED,
6777 rtx x,
6778 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6780 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6781 return data_section;
6782 else
6783 return readonly_data_section;
6786 section *
6787 default_elf_select_rtx_section (machine_mode mode, rtx x,
6788 unsigned HOST_WIDE_INT align)
6790 int reloc = compute_reloc_for_rtx (x);
6792 /* ??? Handle small data here somehow. */
6794 if (reloc & targetm.asm_out.reloc_rw_mask ())
6796 if (reloc == 1)
6797 return get_named_section (NULL, ".data.rel.ro.local", 1);
6798 else
6799 return get_named_section (NULL, ".data.rel.ro", 3);
6802 return mergeable_constant_section (mode, align, 0);
6805 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6807 void
6808 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6810 rtx symbol;
6811 int flags;
6813 /* Careful not to prod global register variables. */
6814 if (!MEM_P (rtl))
6815 return;
6816 symbol = XEXP (rtl, 0);
6817 if (GET_CODE (symbol) != SYMBOL_REF)
6818 return;
6820 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6821 if (TREE_CODE (decl) == FUNCTION_DECL)
6822 flags |= SYMBOL_FLAG_FUNCTION;
6823 if (targetm.binds_local_p (decl))
6824 flags |= SYMBOL_FLAG_LOCAL;
6825 if (VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6826 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6827 else if (targetm.in_small_data_p (decl))
6828 flags |= SYMBOL_FLAG_SMALL;
6829 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6830 being PUBLIC, the thing *must* be defined in this translation unit.
6831 Prevent this buglet from being propagated into rtl code as well. */
6832 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6833 flags |= SYMBOL_FLAG_EXTERNAL;
6835 SYMBOL_REF_FLAGS (symbol) = flags;
6838 /* By default, we do nothing for encode_section_info, so we need not
6839 do anything but discard the '*' marker. */
6841 const char *
6842 default_strip_name_encoding (const char *str)
6844 return str + (*str == '*');
6847 #ifdef ASM_OUTPUT_DEF
6848 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6849 anchor relative to ".", the current section position. */
6851 void
6852 default_asm_output_anchor (rtx symbol)
6854 char buffer[100];
6856 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6857 SYMBOL_REF_BLOCK_OFFSET (symbol));
6858 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6860 #endif
6862 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6864 bool
6865 default_use_anchors_for_symbol_p (const_rtx symbol)
6867 section *sect;
6868 tree decl;
6870 /* Don't use anchors for mergeable sections. The linker might move
6871 the objects around. */
6872 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6873 if (sect->common.flags & SECTION_MERGE)
6874 return false;
6876 /* Don't use anchors for small data sections. The small data register
6877 acts as an anchor for such sections. */
6878 if (sect->common.flags & SECTION_SMALL)
6879 return false;
6881 decl = SYMBOL_REF_DECL (symbol);
6882 if (decl && DECL_P (decl))
6884 /* Don't use section anchors for decls that might be defined or
6885 usurped by other modules. */
6886 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6887 return false;
6889 /* Don't use section anchors for decls that will be placed in a
6890 small data section. */
6891 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6892 one above. The problem is that we only use SECTION_SMALL for
6893 sections that should be marked as small in the section directive. */
6894 if (targetm.in_small_data_p (decl))
6895 return false;
6897 /* Don't use section anchors for decls that won't fit inside a single
6898 anchor range to reduce the amount of instructions required to refer
6899 to the entire declaration. */
6900 if (DECL_SIZE_UNIT (decl) == NULL_TREE
6901 || !tree_fits_uhwi_p (DECL_SIZE_UNIT (decl))
6902 || (tree_to_uhwi (DECL_SIZE_UNIT (decl))
6903 >= (unsigned HOST_WIDE_INT) targetm.max_anchor_offset))
6904 return false;
6907 return true;
6910 /* Return true when RESOLUTION indicate that symbol will be bound to the
6911 definition provided by current .o file. */
6913 static bool
6914 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
6916 return (resolution == LDPR_PREVAILING_DEF
6917 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6918 || resolution == LDPR_PREVAILING_DEF_IRONLY);
6921 /* Return true when RESOLUTION indicate that symbol will be bound locally
6922 within current executable or DSO. */
6924 static bool
6925 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
6927 return (resolution == LDPR_PREVAILING_DEF
6928 || resolution == LDPR_PREVAILING_DEF_IRONLY
6929 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6930 || resolution == LDPR_PREEMPTED_REG
6931 || resolution == LDPR_PREEMPTED_IR
6932 || resolution == LDPR_RESOLVED_IR
6933 || resolution == LDPR_RESOLVED_EXEC);
6936 /* COMMON_LOCAL_P is true means that the linker can guarantee that an
6937 uninitialized common symbol in the executable will still be defined
6938 (through COPY relocation) in the executable. */
6940 bool
6941 default_binds_local_p_3 (const_tree exp, bool shlib, bool weak_dominate,
6942 bool extern_protected_data, bool common_local_p)
6944 /* A non-decl is an entry in the constant pool. */
6945 if (!DECL_P (exp))
6946 return true;
6948 /* Weakrefs may not bind locally, even though the weakref itself is always
6949 static and therefore local. Similarly, the resolver for ifunc functions
6950 might resolve to a non-local function.
6951 FIXME: We can resolve the weakref case more curefuly by looking at the
6952 weakref alias. */
6953 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
6954 || (TREE_CODE (exp) == FUNCTION_DECL
6955 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
6956 return false;
6958 /* Static variables are always local. */
6959 if (! TREE_PUBLIC (exp))
6960 return true;
6962 /* With resolution file in hand, take look into resolutions.
6963 We can't just return true for resolved_locally symbols,
6964 because dynamic linking might overwrite symbols
6965 in shared libraries. */
6966 bool resolved_locally = false;
6968 bool uninited_common = (DECL_COMMON (exp)
6969 && (DECL_INITIAL (exp) == NULL
6970 || (!in_lto_p
6971 && DECL_INITIAL (exp) == error_mark_node)));
6973 /* A non-external variable is defined locally only if it isn't
6974 uninitialized COMMON variable or common_local_p is true. */
6975 bool defined_locally = (!DECL_EXTERNAL (exp)
6976 && (!uninited_common || common_local_p));
6977 if (symtab_node *node = symtab_node::get (exp))
6979 if (node->in_other_partition)
6980 defined_locally = true;
6981 if (node->can_be_discarded_p ())
6983 else if (resolution_to_local_definition_p (node->resolution))
6984 defined_locally = resolved_locally = true;
6985 else if (resolution_local_p (node->resolution))
6986 resolved_locally = true;
6988 if (defined_locally && weak_dominate && !shlib)
6989 resolved_locally = true;
6991 /* Undefined weak symbols are never defined locally. */
6992 if (DECL_WEAK (exp) && !defined_locally)
6993 return false;
6995 /* A symbol is local if the user has said explicitly that it will be,
6996 or if we have a definition for the symbol. We cannot infer visibility
6997 for undefined symbols. */
6998 if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT
6999 && (TREE_CODE (exp) == FUNCTION_DECL
7000 || !extern_protected_data
7001 || DECL_VISIBILITY (exp) != VISIBILITY_PROTECTED)
7002 && (DECL_VISIBILITY_SPECIFIED (exp) || defined_locally))
7003 return true;
7005 /* If PIC, then assume that any global name can be overridden by
7006 symbols resolved from other modules. */
7007 if (shlib)
7008 return false;
7010 /* Variables defined outside this object might not be local. */
7011 if (DECL_EXTERNAL (exp) && !resolved_locally)
7012 return false;
7014 /* Non-dominant weak symbols are not defined locally. */
7015 if (DECL_WEAK (exp) && !resolved_locally)
7016 return false;
7018 /* Uninitialized COMMON variable may be unified with symbols
7019 resolved from other modules. */
7020 if (uninited_common && !resolved_locally)
7021 return false;
7023 /* Otherwise we're left with initialized (or non-common) global data
7024 which is of necessity defined locally. */
7025 return true;
7028 /* Assume ELF-ish defaults, since that's pretty much the most liberal
7029 wrt cross-module name binding. */
7031 bool
7032 default_binds_local_p (const_tree exp)
7034 return default_binds_local_p_3 (exp, flag_shlib != 0, true, false, false);
7037 /* Similar to default_binds_local_p, but common symbol may be local and
7038 extern protected data is non-local. */
7040 bool
7041 default_binds_local_p_2 (const_tree exp)
7043 return default_binds_local_p_3 (exp, flag_shlib != 0, true, true,
7044 !flag_pic);
7047 bool
7048 default_binds_local_p_1 (const_tree exp, int shlib)
7050 return default_binds_local_p_3 (exp, shlib != 0, false, false, false);
7053 /* Return true when references to DECL must bind to current definition in
7054 final executable.
7056 The condition is usually equivalent to whether the function binds to the
7057 current module (shared library or executable), that is to binds_local_p.
7058 We use this fact to avoid need for another target hook and implement
7059 the logic using binds_local_p and just special cases where
7060 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
7061 the weak definitions (that can be overwritten at linktime by other
7062 definition from different object file) and when resolution info is available
7063 we simply use the knowledge passed to us by linker plugin. */
7064 bool
7065 decl_binds_to_current_def_p (const_tree decl)
7067 gcc_assert (DECL_P (decl));
7068 if (!targetm.binds_local_p (decl))
7069 return false;
7070 if (!TREE_PUBLIC (decl))
7071 return true;
7073 /* When resolution is available, just use it. */
7074 if (symtab_node *node = symtab_node::get (decl))
7076 if (node->resolution != LDPR_UNKNOWN
7077 && !node->can_be_discarded_p ())
7078 return resolution_to_local_definition_p (node->resolution);
7081 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
7082 binds locally but still can be overwritten), DECL_COMMON (can be merged
7083 with a non-common definition somewhere in the same module) or
7084 DECL_EXTERNAL.
7085 This rely on fact that binds_local_p behave as decl_replaceable_p
7086 for all other declaration types. */
7087 if (DECL_WEAK (decl))
7088 return false;
7089 if (DECL_COMMON (decl)
7090 && (DECL_INITIAL (decl) == NULL
7091 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
7092 return false;
7093 if (DECL_EXTERNAL (decl))
7094 return false;
7095 return true;
7098 /* A replaceable function or variable is one which may be replaced
7099 at link-time with an entirely different definition, provided that the
7100 replacement has the same type. For example, functions declared
7101 with __attribute__((weak)) on most systems are replaceable.
7103 COMDAT functions are not replaceable, since all definitions of the
7104 function must be equivalent. It is important that COMDAT functions
7105 not be treated as replaceable so that use of C++ template
7106 instantiations is not penalized. */
7108 bool
7109 decl_replaceable_p (tree decl)
7111 gcc_assert (DECL_P (decl));
7112 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
7113 return false;
7114 if (!flag_semantic_interposition
7115 && !DECL_WEAK (decl))
7116 return false;
7117 return !decl_binds_to_current_def_p (decl);
7120 /* Default function to output code that will globalize a label. A
7121 target must define GLOBAL_ASM_OP or provide its own function to
7122 globalize a label. */
7123 #ifdef GLOBAL_ASM_OP
7124 void
7125 default_globalize_label (FILE * stream, const char *name)
7127 fputs (GLOBAL_ASM_OP, stream);
7128 assemble_name (stream, name);
7129 putc ('\n', stream);
7131 #endif /* GLOBAL_ASM_OP */
7133 /* Default function to output code that will globalize a declaration. */
7134 void
7135 default_globalize_decl_name (FILE * stream, tree decl)
7137 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
7138 targetm.asm_out.globalize_label (stream, name);
7141 /* Default function to output a label for unwind information. The
7142 default is to do nothing. A target that needs nonlocal labels for
7143 unwind information must provide its own function to do this. */
7144 void
7145 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
7146 tree decl ATTRIBUTE_UNUSED,
7147 int for_eh ATTRIBUTE_UNUSED,
7148 int empty ATTRIBUTE_UNUSED)
7152 /* Default function to output a label to divide up the exception table.
7153 The default is to do nothing. A target that needs/wants to divide
7154 up the table must provide it's own function to do this. */
7155 void
7156 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
7160 /* This is how to output an internal numbered label where PREFIX is
7161 the class of label and LABELNO is the number within the class. */
7163 void
7164 default_generate_internal_label (char *buf, const char *prefix,
7165 unsigned long labelno)
7167 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
7170 /* This is how to output an internal numbered label where PREFIX is
7171 the class of label and LABELNO is the number within the class. */
7173 void
7174 default_internal_label (FILE *stream, const char *prefix,
7175 unsigned long labelno)
7177 char *const buf = (char *) alloca (40 + strlen (prefix));
7178 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
7179 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
7183 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
7185 void
7186 default_asm_declare_constant_name (FILE *file, const char *name,
7187 const_tree exp ATTRIBUTE_UNUSED,
7188 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
7190 assemble_label (file, name);
7193 /* This is the default behavior at the beginning of a file. It's
7194 controlled by two other target-hook toggles. */
7195 void
7196 default_file_start (void)
7198 if (targetm.asm_file_start_app_off
7199 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
7200 fputs (ASM_APP_OFF, asm_out_file);
7202 if (targetm.asm_file_start_file_directive)
7204 /* LTO produced units have no meaningful main_input_filename. */
7205 if (in_lto_p)
7206 output_file_directive (asm_out_file, "<artificial>");
7207 else
7208 output_file_directive (asm_out_file, main_input_filename);
7212 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
7213 which emits a special section directive used to indicate whether or
7214 not this object file needs an executable stack. This is primarily
7215 a GNU extension to ELF but could be used on other targets. */
7217 int trampolines_created;
7219 void
7220 file_end_indicate_exec_stack (void)
7222 unsigned int flags = SECTION_DEBUG;
7223 if (trampolines_created)
7224 flags |= SECTION_CODE;
7226 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
7229 /* Emit a special section directive to indicate that this object file
7230 was compiled with -fsplit-stack. This is used to let the linker
7231 detect calls between split-stack code and non-split-stack code, so
7232 that it can modify the split-stack code to allocate a sufficiently
7233 large stack. We emit another special section if there are any
7234 functions in this file which have the no_split_stack attribute, to
7235 prevent the linker from warning about being unable to convert the
7236 functions if they call non-split-stack code. */
7238 void
7239 file_end_indicate_split_stack (void)
7241 if (flag_split_stack)
7243 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
7244 NULL));
7245 if (saw_no_split_stack)
7246 switch_to_section (get_section (".note.GNU-no-split-stack",
7247 SECTION_DEBUG, NULL));
7251 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
7252 a get_unnamed_section callback. */
7254 void
7255 output_section_asm_op (const void *directive)
7257 fprintf (asm_out_file, "%s\n", (const char *) directive);
7260 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
7261 the current section is NEW_SECTION. */
7263 void
7264 switch_to_section (section *new_section)
7266 if (in_section == new_section)
7267 return;
7269 if (new_section->common.flags & SECTION_FORGET)
7270 in_section = NULL;
7271 else
7272 in_section = new_section;
7274 switch (SECTION_STYLE (new_section))
7276 case SECTION_NAMED:
7277 targetm.asm_out.named_section (new_section->named.name,
7278 new_section->named.common.flags,
7279 new_section->named.decl);
7280 break;
7282 case SECTION_UNNAMED:
7283 new_section->unnamed.callback (new_section->unnamed.data);
7284 break;
7286 case SECTION_NOSWITCH:
7287 gcc_unreachable ();
7288 break;
7291 new_section->common.flags |= SECTION_DECLARED;
7294 /* If block symbol SYMBOL has not yet been assigned an offset, place
7295 it at the end of its block. */
7297 void
7298 place_block_symbol (rtx symbol)
7300 unsigned HOST_WIDE_INT size, mask, offset;
7301 struct constant_descriptor_rtx *desc;
7302 unsigned int alignment;
7303 struct object_block *block;
7304 tree decl;
7306 gcc_assert (SYMBOL_REF_BLOCK (symbol));
7307 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7308 return;
7310 /* Work out the symbol's size and alignment. */
7311 if (CONSTANT_POOL_ADDRESS_P (symbol))
7313 desc = SYMBOL_REF_CONSTANT (symbol);
7314 alignment = desc->align;
7315 size = GET_MODE_SIZE (desc->mode);
7317 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7319 decl = SYMBOL_REF_DECL (symbol);
7320 gcc_checking_assert (DECL_IN_CONSTANT_POOL (decl));
7321 alignment = DECL_ALIGN (decl);
7322 size = get_constant_size (DECL_INITIAL (decl));
7323 if ((flag_sanitize & SANITIZE_ADDRESS)
7324 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7325 && asan_protect_global (DECL_INITIAL (decl)))
7327 size += asan_red_zone_size (size);
7328 alignment = MAX (alignment,
7329 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7332 else
7334 struct symtab_node *snode;
7335 decl = SYMBOL_REF_DECL (symbol);
7337 snode = symtab_node::get (decl);
7338 if (snode->alias)
7340 rtx target = DECL_RTL (snode->ultimate_alias_target ()->decl);
7342 gcc_assert (MEM_P (target)
7343 && GET_CODE (XEXP (target, 0)) == SYMBOL_REF
7344 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (target, 0)));
7345 target = XEXP (target, 0);
7346 place_block_symbol (target);
7347 SYMBOL_REF_BLOCK_OFFSET (symbol) = SYMBOL_REF_BLOCK_OFFSET (target);
7348 return;
7350 alignment = get_variable_align (decl);
7351 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7352 if ((flag_sanitize & SANITIZE_ADDRESS)
7353 && asan_protect_global (decl))
7355 size += asan_red_zone_size (size);
7356 alignment = MAX (alignment,
7357 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7361 /* Calculate the object's offset from the start of the block. */
7362 block = SYMBOL_REF_BLOCK (symbol);
7363 mask = alignment / BITS_PER_UNIT - 1;
7364 offset = (block->size + mask) & ~mask;
7365 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7367 /* Record the block's new alignment and size. */
7368 block->alignment = MAX (block->alignment, alignment);
7369 block->size = offset + size;
7371 vec_safe_push (block->objects, symbol);
7374 /* Return the anchor that should be used to address byte offset OFFSET
7375 from the first object in BLOCK. MODEL is the TLS model used
7376 to access it. */
7379 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7380 enum tls_model model)
7382 char label[100];
7383 unsigned int begin, middle, end;
7384 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7385 rtx anchor;
7387 /* Work out the anchor's offset. Use an offset of 0 for the first
7388 anchor so that we don't pessimize the case where we take the address
7389 of a variable at the beginning of the block. This is particularly
7390 useful when a block has only one variable assigned to it.
7392 We try to place anchors RANGE bytes apart, so there can then be
7393 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7394 a ptr_mode offset. With some target settings, the lowest such
7395 anchor might be out of range for the lowest ptr_mode offset;
7396 likewise the highest anchor for the highest offset. Use anchors
7397 at the extreme ends of the ptr_mode range in such cases.
7399 All arithmetic uses unsigned integers in order to avoid
7400 signed overflow. */
7401 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7402 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7403 range = max_offset - min_offset + 1;
7404 if (range == 0)
7405 offset = 0;
7406 else
7408 bias = HOST_WIDE_INT_1U << (GET_MODE_BITSIZE (ptr_mode) - 1);
7409 if (offset < 0)
7411 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7412 delta -= delta % range;
7413 if (delta > bias)
7414 delta = bias;
7415 offset = (HOST_WIDE_INT) (-delta);
7417 else
7419 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7420 delta -= delta % range;
7421 if (delta > bias - 1)
7422 delta = bias - 1;
7423 offset = (HOST_WIDE_INT) delta;
7427 /* Do a binary search to see if there's already an anchor we can use.
7428 Set BEGIN to the new anchor's index if not. */
7429 begin = 0;
7430 end = vec_safe_length (block->anchors);
7431 while (begin != end)
7433 middle = (end + begin) / 2;
7434 anchor = (*block->anchors)[middle];
7435 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7436 end = middle;
7437 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7438 begin = middle + 1;
7439 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7440 end = middle;
7441 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7442 begin = middle + 1;
7443 else
7444 return anchor;
7447 /* Create a new anchor with a unique label. */
7448 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7449 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7450 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7451 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7453 /* Insert it at index BEGIN. */
7454 vec_safe_insert (block->anchors, begin, anchor);
7455 return anchor;
7458 /* Output the objects in BLOCK. */
7460 static void
7461 output_object_block (struct object_block *block)
7463 struct constant_descriptor_rtx *desc;
7464 unsigned int i;
7465 HOST_WIDE_INT offset;
7466 tree decl;
7467 rtx symbol;
7469 if (!block->objects)
7470 return;
7472 /* Switch to the section and make sure that the first byte is
7473 suitably aligned. */
7474 /* Special case VTV comdat sections similar to assemble_variable. */
7475 if (SECTION_STYLE (block->sect) == SECTION_NAMED
7476 && block->sect->named.name
7477 && (strcmp (block->sect->named.name, ".vtable_map_vars") == 0))
7478 handle_vtv_comdat_section (block->sect, block->sect->named.decl);
7479 else
7480 switch_to_section (block->sect);
7482 assemble_align (block->alignment);
7484 /* Define the values of all anchors relative to the current section
7485 position. */
7486 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7487 targetm.asm_out.output_anchor (symbol);
7489 /* Output the objects themselves. */
7490 offset = 0;
7491 FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7493 /* Move to the object's offset, padding with zeros if necessary. */
7494 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7495 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7496 if (CONSTANT_POOL_ADDRESS_P (symbol))
7498 desc = SYMBOL_REF_CONSTANT (symbol);
7499 /* Pass 1 for align as we have already laid out everything in the block.
7500 So aligning shouldn't be necessary. */
7501 output_constant_pool_1 (desc, 1);
7502 offset += GET_MODE_SIZE (desc->mode);
7504 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7506 HOST_WIDE_INT size;
7507 decl = SYMBOL_REF_DECL (symbol);
7508 assemble_constant_contents
7509 (DECL_INITIAL (decl), XSTR (symbol, 0), DECL_ALIGN (decl));
7511 size = get_constant_size (DECL_INITIAL (decl));
7512 offset += size;
7513 if ((flag_sanitize & SANITIZE_ADDRESS)
7514 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7515 && asan_protect_global (DECL_INITIAL (decl)))
7517 size = asan_red_zone_size (size);
7518 assemble_zeros (size);
7519 offset += size;
7522 else
7524 HOST_WIDE_INT size;
7525 decl = SYMBOL_REF_DECL (symbol);
7526 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7527 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7528 offset += size;
7529 if ((flag_sanitize & SANITIZE_ADDRESS)
7530 && asan_protect_global (decl))
7532 size = asan_red_zone_size (size);
7533 assemble_zeros (size);
7534 offset += size;
7540 /* A callback for qsort to compare object_blocks. */
7542 static int
7543 output_object_block_compare (const void *x, const void *y)
7545 object_block *p1 = *(object_block * const*)x;
7546 object_block *p2 = *(object_block * const*)y;
7548 if (p1->sect->common.flags & SECTION_NAMED
7549 && !(p2->sect->common.flags & SECTION_NAMED))
7550 return 1;
7552 if (!(p1->sect->common.flags & SECTION_NAMED)
7553 && p2->sect->common.flags & SECTION_NAMED)
7554 return -1;
7556 if (p1->sect->common.flags & SECTION_NAMED
7557 && p2->sect->common.flags & SECTION_NAMED)
7558 return strcmp (p1->sect->named.name, p2->sect->named.name);
7560 unsigned f1 = p1->sect->common.flags;
7561 unsigned f2 = p2->sect->common.flags;
7562 if (f1 == f2)
7563 return 0;
7564 return f1 < f2 ? -1 : 1;
7567 /* Output the definitions of all object_blocks. */
7569 void
7570 output_object_blocks (void)
7572 vec<object_block *, va_heap> v;
7573 v.create (object_block_htab->elements ());
7574 object_block *obj;
7575 hash_table<object_block_hasher>::iterator hi;
7577 FOR_EACH_HASH_TABLE_ELEMENT (*object_block_htab, obj, object_block *, hi)
7578 v.quick_push (obj);
7580 /* Sort them in order to output them in a deterministic manner,
7581 otherwise we may get .rodata sections in different orders with
7582 and without -g. */
7583 v.qsort (output_object_block_compare);
7584 unsigned i;
7585 FOR_EACH_VEC_ELT (v, i, obj)
7586 output_object_block (obj);
7588 v.release ();
7591 /* This function provides a possible implementation of the
7592 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7593 by -frecord-gcc-switches it creates a new mergeable, string section in the
7594 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7595 contains the switches in ASCII format.
7597 FIXME: This code does not correctly handle double quote characters
7598 that appear inside strings, (it strips them rather than preserving them).
7599 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7600 characters - instead it treats them as sub-string separators. Since
7601 we want to emit NUL strings terminators into the object file we have to use
7602 ASM_OUTPUT_SKIP. */
7605 elf_record_gcc_switches (print_switch_type type, const char * name)
7607 switch (type)
7609 case SWITCH_TYPE_PASSED:
7610 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7611 ASM_OUTPUT_SKIP (asm_out_file, HOST_WIDE_INT_1U);
7612 break;
7614 case SWITCH_TYPE_DESCRIPTIVE:
7615 if (name == NULL)
7617 /* Distinguish between invocations where name is NULL. */
7618 static bool started = false;
7620 if (!started)
7622 section * sec;
7624 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7625 SECTION_DEBUG
7626 | SECTION_MERGE
7627 | SECTION_STRINGS
7628 | (SECTION_ENTSIZE & 1),
7629 NULL);
7630 switch_to_section (sec);
7631 started = true;
7635 default:
7636 break;
7639 /* The return value is currently ignored by the caller, but must be 0.
7640 For -fverbose-asm the return value would be the number of characters
7641 emitted into the assembler file. */
7642 return 0;
7645 /* Emit text to declare externally defined symbols. It is needed to
7646 properly support non-default visibility. */
7647 void
7648 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7649 tree decl,
7650 const char *name ATTRIBUTE_UNUSED)
7652 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7653 set in order to avoid putting out names that are never really
7654 used. Always output visibility specified in the source. */
7655 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7656 && (DECL_VISIBILITY_SPECIFIED (decl)
7657 || targetm.binds_local_p (decl)))
7658 maybe_assemble_visibility (decl);
7661 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7663 void
7664 default_asm_output_source_filename (FILE *file, const char *name)
7666 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7667 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7668 #else
7669 fprintf (file, "\t.file\t");
7670 output_quoted_string (file, name);
7671 putc ('\n', file);
7672 #endif
7675 /* Output a file name in the form wanted by System V. */
7677 void
7678 output_file_directive (FILE *asm_file, const char *input_name)
7680 int len;
7681 const char *na;
7683 if (input_name == NULL)
7684 input_name = "<stdin>";
7685 else
7686 input_name = remap_debug_filename (input_name);
7688 len = strlen (input_name);
7689 na = input_name + len;
7691 /* NA gets INPUT_NAME sans directory names. */
7692 while (na > input_name)
7694 if (IS_DIR_SEPARATOR (na[-1]))
7695 break;
7696 na--;
7699 targetm.asm_out.output_source_filename (asm_file, na);
7702 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7703 EXP. */
7705 make_debug_expr_from_rtl (const_rtx exp)
7707 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7708 machine_mode mode = GET_MODE (exp);
7709 rtx dval;
7711 DECL_ARTIFICIAL (ddecl) = 1;
7712 if (REG_P (exp) && REG_EXPR (exp))
7713 type = TREE_TYPE (REG_EXPR (exp));
7714 else if (MEM_P (exp) && MEM_EXPR (exp))
7715 type = TREE_TYPE (MEM_EXPR (exp));
7716 else
7717 type = NULL_TREE;
7718 if (type && TYPE_MODE (type) == mode)
7719 TREE_TYPE (ddecl) = type;
7720 else
7721 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7722 SET_DECL_MODE (ddecl, mode);
7723 dval = gen_rtx_DEBUG_EXPR (mode);
7724 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7725 SET_DECL_RTL (ddecl, dval);
7726 return dval;
7729 #ifdef ELF_ASCII_ESCAPES
7730 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7732 void
7733 default_elf_asm_output_limited_string (FILE *f, const char *s)
7735 int escape;
7736 unsigned char c;
7738 fputs (STRING_ASM_OP, f);
7739 putc ('"', f);
7740 while (*s != '\0')
7742 c = *s;
7743 escape = ELF_ASCII_ESCAPES[c];
7744 switch (escape)
7746 case 0:
7747 putc (c, f);
7748 break;
7749 case 1:
7750 putc ('\\', f);
7751 putc ('0'+((c>>6)&7), f);
7752 putc ('0'+((c>>3)&7), f);
7753 putc ('0'+(c&7), f);
7754 break;
7755 default:
7756 putc ('\\', f);
7757 putc (escape, f);
7758 break;
7760 s++;
7762 putc ('\"', f);
7763 putc ('\n', f);
7766 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7768 void
7769 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7771 const char *limit = s + len;
7772 const char *last_null = NULL;
7773 unsigned bytes_in_chunk = 0;
7774 unsigned char c;
7775 int escape;
7777 for (; s < limit; s++)
7779 const char *p;
7781 if (bytes_in_chunk >= 60)
7783 putc ('\"', f);
7784 putc ('\n', f);
7785 bytes_in_chunk = 0;
7788 if (s > last_null)
7790 for (p = s; p < limit && *p != '\0'; p++)
7791 continue;
7792 last_null = p;
7794 else
7795 p = last_null;
7797 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7799 if (bytes_in_chunk > 0)
7801 putc ('\"', f);
7802 putc ('\n', f);
7803 bytes_in_chunk = 0;
7806 default_elf_asm_output_limited_string (f, s);
7807 s = p;
7809 else
7811 if (bytes_in_chunk == 0)
7812 fputs (ASCII_DATA_ASM_OP "\"", f);
7814 c = *s;
7815 escape = ELF_ASCII_ESCAPES[c];
7816 switch (escape)
7818 case 0:
7819 putc (c, f);
7820 bytes_in_chunk++;
7821 break;
7822 case 1:
7823 putc ('\\', f);
7824 putc ('0'+((c>>6)&7), f);
7825 putc ('0'+((c>>3)&7), f);
7826 putc ('0'+(c&7), f);
7827 bytes_in_chunk += 4;
7828 break;
7829 default:
7830 putc ('\\', f);
7831 putc (escape, f);
7832 bytes_in_chunk += 2;
7833 break;
7839 if (bytes_in_chunk > 0)
7841 putc ('\"', f);
7842 putc ('\n', f);
7845 #endif
7847 static GTY(()) section *elf_init_array_section;
7848 static GTY(()) section *elf_fini_array_section;
7850 static section *
7851 get_elf_initfini_array_priority_section (int priority,
7852 bool constructor_p)
7854 section *sec;
7855 if (priority != DEFAULT_INIT_PRIORITY)
7857 char buf[18];
7858 sprintf (buf, "%s.%.5u",
7859 constructor_p ? ".init_array" : ".fini_array",
7860 priority);
7861 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7863 else
7865 if (constructor_p)
7867 if (elf_init_array_section == NULL)
7868 elf_init_array_section
7869 = get_section (".init_array",
7870 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7871 sec = elf_init_array_section;
7873 else
7875 if (elf_fini_array_section == NULL)
7876 elf_fini_array_section
7877 = get_section (".fini_array",
7878 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7879 sec = elf_fini_array_section;
7882 return sec;
7885 /* Use .init_array section for constructors. */
7887 void
7888 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7890 section *sec = get_elf_initfini_array_priority_section (priority,
7891 true);
7892 assemble_addr_to_section (symbol, sec);
7895 /* Use .fini_array section for destructors. */
7897 void
7898 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7900 section *sec = get_elf_initfini_array_priority_section (priority,
7901 false);
7902 assemble_addr_to_section (symbol, sec);
7905 /* Default TARGET_ASM_OUTPUT_IDENT hook.
7907 This is a bit of a cheat. The real default is a no-op, but this
7908 hook is the default for all targets with a .ident directive. */
7910 void
7911 default_asm_output_ident_directive (const char *ident_str)
7913 const char *ident_asm_op = "\t.ident\t";
7915 /* If we are still in the front end, do not write out the string
7916 to asm_out_file. Instead, add a fake top-level asm statement.
7917 This allows the front ends to use this hook without actually
7918 writing to asm_out_file, to handle #ident or Pragma Ident. */
7919 if (symtab->state == PARSING)
7921 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
7922 symtab->finalize_toplevel_asm (build_string (strlen (buf), buf));
7924 else
7925 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
7929 /* This function ensures that vtable_map variables are not only
7930 in the comdat section, but that each variable has its own unique
7931 comdat name. Without this the variables end up in the same section
7932 with a single comdat name.
7934 FIXME: resolve_unique_section needs to deal better with
7935 decls with both DECL_SECTION_NAME and DECL_ONE_ONLY. Once
7936 that is fixed, this if-else statement can be replaced with
7937 a single call to "switch_to_section (sect)". */
7939 static void
7940 handle_vtv_comdat_section (section *sect, const_tree decl ATTRIBUTE_UNUSED)
7942 #if defined (OBJECT_FORMAT_ELF)
7943 targetm.asm_out.named_section (sect->named.name,
7944 sect->named.common.flags
7945 | SECTION_LINKONCE,
7946 DECL_NAME (decl));
7947 in_section = sect;
7948 #else
7949 /* Neither OBJECT_FORMAT_PE, nor OBJECT_FORMAT_COFF is set here.
7950 Therefore the following check is used.
7951 In case a the target is PE or COFF a comdat group section
7952 is created, e.g. .vtable_map_vars$foo. The linker places
7953 everything in .vtable_map_vars at the end.
7955 A fix could be made in
7956 gcc/config/i386/winnt.c: i386_pe_unique_section. */
7957 if (TARGET_PECOFF)
7959 char *name;
7961 if (TREE_CODE (DECL_NAME (decl)) == IDENTIFIER_NODE)
7962 name = ACONCAT ((sect->named.name, "$",
7963 IDENTIFIER_POINTER (DECL_NAME (decl)), NULL));
7964 else
7965 name = ACONCAT ((sect->named.name, "$",
7966 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (DECL_NAME (decl))),
7967 NULL));
7969 targetm.asm_out.named_section (name,
7970 sect->named.common.flags
7971 | SECTION_LINKONCE,
7972 DECL_NAME (decl));
7973 in_section = sect;
7975 else
7976 switch_to_section (sect);
7977 #endif
7980 #include "gt-varasm.h"