Daily bump.
[official-gcc.git] / gcc / varasm.c
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1 /* Output variables, constants and external declarations, for GNU compiler.
2 Copyright (C) 1987-2018 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
21 /* This file handles generation of all the assembler code
22 *except* the instructions of a function.
23 This includes declarations of variables and their initial values.
25 We also output the assembler code for constants stored in memory
26 and are responsible for combining constants with the same value. */
28 #include "config.h"
29 #include "system.h"
30 #include "coretypes.h"
31 #include "backend.h"
32 #include "target.h"
33 #include "rtl.h"
34 #include "tree.h"
35 #include "predict.h"
36 #include "memmodel.h"
37 #include "tm_p.h"
38 #include "stringpool.h"
39 #include "regs.h"
40 #include "emit-rtl.h"
41 #include "cgraph.h"
42 #include "diagnostic-core.h"
43 #include "fold-const.h"
44 #include "stor-layout.h"
45 #include "varasm.h"
46 #include "flags.h"
47 #include "stmt.h"
48 #include "expr.h"
49 #include "expmed.h"
50 #include "output.h"
51 #include "langhooks.h"
52 #include "debug.h"
53 #include "common/common-target.h"
54 #include "stringpool.h"
55 #include "attribs.h"
56 #include "asan.h"
57 #include "rtl-iter.h"
58 #include "file-prefix-map.h" /* remap_debug_filename() */
60 #ifdef XCOFF_DEBUGGING_INFO
61 #include "xcoffout.h" /* Needed for external data declarations. */
62 #endif
64 /* The (assembler) name of the first globally-visible object output. */
65 extern GTY(()) const char *first_global_object_name;
66 extern GTY(()) const char *weak_global_object_name;
68 const char *first_global_object_name;
69 const char *weak_global_object_name;
71 struct addr_const;
72 struct constant_descriptor_rtx;
73 struct rtx_constant_pool;
75 #define n_deferred_constants (crtl->varasm.deferred_constants)
77 /* Number for making the label on the next
78 constant that is stored in memory. */
80 static GTY(()) int const_labelno;
82 /* Carry information from ASM_DECLARE_OBJECT_NAME
83 to ASM_FINISH_DECLARE_OBJECT. */
85 int size_directive_output;
87 /* The last decl for which assemble_variable was called,
88 if it did ASM_DECLARE_OBJECT_NAME.
89 If the last call to assemble_variable didn't do that,
90 this holds 0. */
92 tree last_assemble_variable_decl;
94 /* The following global variable indicates if the first basic block
95 in a function belongs to the cold partition or not. */
97 bool first_function_block_is_cold;
99 /* Whether we saw any functions with no_split_stack. */
101 static bool saw_no_split_stack;
103 static const char *strip_reg_name (const char *);
104 static int contains_pointers_p (tree);
105 #ifdef ASM_OUTPUT_EXTERNAL
106 static bool incorporeal_function_p (tree);
107 #endif
108 static void decode_addr_const (tree, struct addr_const *);
109 static hashval_t const_hash_1 (const tree);
110 static int compare_constant (const tree, const tree);
111 static void output_constant_def_contents (rtx);
112 static void output_addressed_constants (tree);
113 static unsigned HOST_WIDE_INT output_constant (tree, unsigned HOST_WIDE_INT,
114 unsigned int, bool);
115 static void globalize_decl (tree);
116 static bool decl_readonly_section_1 (enum section_category);
117 #ifdef BSS_SECTION_ASM_OP
118 #ifdef ASM_OUTPUT_ALIGNED_BSS
119 static void asm_output_aligned_bss (FILE *, tree, const char *,
120 unsigned HOST_WIDE_INT, int)
121 ATTRIBUTE_UNUSED;
122 #endif
123 #endif /* BSS_SECTION_ASM_OP */
124 static void mark_weak (tree);
125 static void output_constant_pool (const char *, tree);
126 static void handle_vtv_comdat_section (section *, const_tree);
128 /* Well-known sections, each one associated with some sort of *_ASM_OP. */
129 section *text_section;
130 section *data_section;
131 section *readonly_data_section;
132 section *sdata_section;
133 section *ctors_section;
134 section *dtors_section;
135 section *bss_section;
136 section *sbss_section;
138 /* Various forms of common section. All are guaranteed to be nonnull. */
139 section *tls_comm_section;
140 section *comm_section;
141 section *lcomm_section;
143 /* A SECTION_NOSWITCH section used for declaring global BSS variables.
144 May be null. */
145 section *bss_noswitch_section;
147 /* The section that holds the main exception table, when known. The section
148 is set either by the target's init_sections hook or by the first call to
149 switch_to_exception_section. */
150 section *exception_section;
152 /* The section that holds the DWARF2 frame unwind information, when known.
153 The section is set either by the target's init_sections hook or by the
154 first call to switch_to_eh_frame_section. */
155 section *eh_frame_section;
157 /* asm_out_file's current section. This is NULL if no section has yet
158 been selected or if we lose track of what the current section is. */
159 section *in_section;
161 /* True if code for the current function is currently being directed
162 at the cold section. */
163 bool in_cold_section_p;
165 /* The following global holds the "function name" for the code in the
166 cold section of a function, if hot/cold function splitting is enabled
167 and there was actually code that went into the cold section. A
168 pseudo function name is needed for the cold section of code for some
169 debugging tools that perform symbolization. */
170 tree cold_function_name = NULL_TREE;
172 /* A linked list of all the unnamed sections. */
173 static GTY(()) section *unnamed_sections;
175 /* Return a nonzero value if DECL has a section attribute. */
176 #define IN_NAMED_SECTION(DECL) \
177 (VAR_OR_FUNCTION_DECL_P (DECL) && DECL_SECTION_NAME (DECL) != NULL)
179 struct section_hasher : ggc_ptr_hash<section>
181 typedef const char *compare_type;
183 static hashval_t hash (section *);
184 static bool equal (section *, const char *);
187 /* Hash table of named sections. */
188 static GTY(()) hash_table<section_hasher> *section_htab;
190 struct object_block_hasher : ggc_ptr_hash<object_block>
192 typedef const section *compare_type;
194 static hashval_t hash (object_block *);
195 static bool equal (object_block *, const section *);
198 /* A table of object_blocks, indexed by section. */
199 static GTY(()) hash_table<object_block_hasher> *object_block_htab;
201 /* The next number to use for internal anchor labels. */
202 static GTY(()) int anchor_labelno;
204 /* A pool of constants that can be shared between functions. */
205 static GTY(()) struct rtx_constant_pool *shared_constant_pool;
207 /* Helper routines for maintaining section_htab. */
209 bool
210 section_hasher::equal (section *old, const char *new_name)
212 return strcmp (old->named.name, new_name) == 0;
215 hashval_t
216 section_hasher::hash (section *old)
218 return htab_hash_string (old->named.name);
221 /* Return a hash value for section SECT. */
223 static hashval_t
224 hash_section (section *sect)
226 if (sect->common.flags & SECTION_NAMED)
227 return htab_hash_string (sect->named.name);
228 return sect->common.flags & ~SECTION_DECLARED;
231 /* Helper routines for maintaining object_block_htab. */
233 inline bool
234 object_block_hasher::equal (object_block *old, const section *new_section)
236 return old->sect == new_section;
239 hashval_t
240 object_block_hasher::hash (object_block *old)
242 return hash_section (old->sect);
245 /* Return a new unnamed section with the given fields. */
247 section *
248 get_unnamed_section (unsigned int flags, void (*callback) (const void *),
249 const void *data)
251 section *sect;
253 sect = ggc_alloc<section> ();
254 sect->unnamed.common.flags = flags | SECTION_UNNAMED;
255 sect->unnamed.callback = callback;
256 sect->unnamed.data = data;
257 sect->unnamed.next = unnamed_sections;
259 unnamed_sections = sect;
260 return sect;
263 /* Return a SECTION_NOSWITCH section with the given fields. */
265 static section *
266 get_noswitch_section (unsigned int flags, noswitch_section_callback callback)
268 section *sect;
270 sect = ggc_alloc<section> ();
271 sect->noswitch.common.flags = flags | SECTION_NOSWITCH;
272 sect->noswitch.callback = callback;
274 return sect;
277 /* Return the named section structure associated with NAME. Create
278 a new section with the given fields if no such structure exists. */
280 section *
281 get_section (const char *name, unsigned int flags, tree decl)
283 section *sect, **slot;
285 slot = section_htab->find_slot_with_hash (name, htab_hash_string (name),
286 INSERT);
287 flags |= SECTION_NAMED;
288 if (*slot == NULL)
290 sect = ggc_alloc<section> ();
291 sect->named.common.flags = flags;
292 sect->named.name = ggc_strdup (name);
293 sect->named.decl = decl;
294 *slot = sect;
296 else
298 sect = *slot;
299 /* It is fine if one of the sections has SECTION_NOTYPE as long as
300 the other has none of the contrary flags (see the logic at the end
301 of default_section_type_flags, below). */
302 if (((sect->common.flags ^ flags) & SECTION_NOTYPE)
303 && !((sect->common.flags | flags)
304 & (SECTION_CODE | SECTION_BSS | SECTION_TLS | SECTION_ENTSIZE
305 | (HAVE_COMDAT_GROUP ? SECTION_LINKONCE : 0))))
307 sect->common.flags |= SECTION_NOTYPE;
308 flags |= SECTION_NOTYPE;
310 if ((sect->common.flags & ~SECTION_DECLARED) != flags
311 && ((sect->common.flags | flags) & SECTION_OVERRIDE) == 0)
313 /* It is fine if one of the section flags is
314 SECTION_WRITE | SECTION_RELRO and the other has none of these
315 flags (i.e. read-only) in named sections and either the
316 section hasn't been declared yet or has been declared as writable.
317 In that case just make sure the resulting flags are
318 SECTION_WRITE | SECTION_RELRO, ie. writable only because of
319 relocations. */
320 if (((sect->common.flags ^ flags) & (SECTION_WRITE | SECTION_RELRO))
321 == (SECTION_WRITE | SECTION_RELRO)
322 && (sect->common.flags
323 & ~(SECTION_DECLARED | SECTION_WRITE | SECTION_RELRO))
324 == (flags & ~(SECTION_WRITE | SECTION_RELRO))
325 && ((sect->common.flags & SECTION_DECLARED) == 0
326 || (sect->common.flags & SECTION_WRITE)))
328 sect->common.flags |= (SECTION_WRITE | SECTION_RELRO);
329 return sect;
331 /* Sanity check user variables for flag changes. */
332 if (sect->named.decl != NULL
333 && DECL_P (sect->named.decl)
334 && decl != sect->named.decl)
336 if (decl != NULL && DECL_P (decl))
337 error ("%+qD causes a section type conflict with %qD",
338 decl, sect->named.decl);
339 else
340 error ("section type conflict with %qD", sect->named.decl);
341 inform (DECL_SOURCE_LOCATION (sect->named.decl),
342 "%qD was declared here", sect->named.decl);
344 else if (decl != NULL && DECL_P (decl))
345 error ("%+qD causes a section type conflict", decl);
346 else
347 error ("section type conflict");
348 /* Make sure we don't error about one section multiple times. */
349 sect->common.flags |= SECTION_OVERRIDE;
352 return sect;
355 /* Return true if the current compilation mode benefits from having
356 objects grouped into blocks. */
358 static bool
359 use_object_blocks_p (void)
361 return flag_section_anchors;
364 /* Return the object_block structure for section SECT. Create a new
365 structure if we haven't created one already. Return null if SECT
366 itself is null. */
368 static struct object_block *
369 get_block_for_section (section *sect)
371 struct object_block *block;
373 if (sect == NULL)
374 return NULL;
376 object_block **slot
377 = object_block_htab->find_slot_with_hash (sect, hash_section (sect),
378 INSERT);
379 block = *slot;
380 if (block == NULL)
382 block = ggc_cleared_alloc<object_block> ();
383 block->sect = sect;
384 *slot = block;
386 return block;
389 /* Create a symbol with label LABEL and place it at byte offset
390 OFFSET in BLOCK. OFFSET can be negative if the symbol's offset
391 is not yet known. LABEL must be a garbage-collected string. */
393 static rtx
394 create_block_symbol (const char *label, struct object_block *block,
395 HOST_WIDE_INT offset)
397 rtx symbol;
398 unsigned int size;
400 /* Create the extended SYMBOL_REF. */
401 size = RTX_HDR_SIZE + sizeof (struct block_symbol);
402 symbol = (rtx) ggc_internal_alloc (size);
404 /* Initialize the normal SYMBOL_REF fields. */
405 memset (symbol, 0, size);
406 PUT_CODE (symbol, SYMBOL_REF);
407 PUT_MODE (symbol, Pmode);
408 XSTR (symbol, 0) = label;
409 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_HAS_BLOCK_INFO;
411 /* Initialize the block_symbol stuff. */
412 SYMBOL_REF_BLOCK (symbol) = block;
413 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
415 return symbol;
418 /* Return a section with a particular name and with whatever SECTION_*
419 flags section_type_flags deems appropriate. The name of the section
420 is taken from NAME if nonnull, otherwise it is taken from DECL's
421 DECL_SECTION_NAME. DECL is the decl associated with the section
422 (see the section comment for details) and RELOC is as for
423 section_type_flags. */
425 section *
426 get_named_section (tree decl, const char *name, int reloc)
428 unsigned int flags;
430 if (name == NULL)
432 gcc_assert (decl && DECL_P (decl) && DECL_SECTION_NAME (decl));
433 name = DECL_SECTION_NAME (decl);
436 flags = targetm.section_type_flags (decl, name, reloc);
437 return get_section (name, flags, decl);
440 /* Worker for resolve_unique_section. */
442 static bool
443 set_implicit_section (struct symtab_node *n, void *data ATTRIBUTE_UNUSED)
445 n->implicit_section = true;
446 return false;
449 /* If required, set DECL_SECTION_NAME to a unique name. */
451 void
452 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
453 int flag_function_or_data_sections)
455 if (DECL_SECTION_NAME (decl) == NULL
456 && targetm_common.have_named_sections
457 && (flag_function_or_data_sections
458 || DECL_COMDAT_GROUP (decl)))
460 targetm.asm_out.unique_section (decl, reloc);
461 if (DECL_SECTION_NAME (decl))
462 symtab_node::get (decl)->call_for_symbol_and_aliases
463 (set_implicit_section, NULL, true);
467 #ifdef BSS_SECTION_ASM_OP
469 #ifdef ASM_OUTPUT_ALIGNED_BSS
471 /* Utility function for targets to use in implementing
472 ASM_OUTPUT_ALIGNED_BSS.
473 ??? It is believed that this function will work in most cases so such
474 support is localized here. */
476 static void
477 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
478 const char *name, unsigned HOST_WIDE_INT size,
479 int align)
481 switch_to_section (bss_section);
482 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
483 #ifdef ASM_DECLARE_OBJECT_NAME
484 last_assemble_variable_decl = decl;
485 ASM_DECLARE_OBJECT_NAME (file, name, decl);
486 #else
487 /* Standard thing is just output label for the object. */
488 ASM_OUTPUT_LABEL (file, name);
489 #endif /* ASM_DECLARE_OBJECT_NAME */
490 ASM_OUTPUT_SKIP (file, size ? size : 1);
493 #endif
495 #endif /* BSS_SECTION_ASM_OP */
497 #ifndef USE_SELECT_SECTION_FOR_FUNCTIONS
498 /* Return the hot section for function DECL. Return text_section for
499 null DECLs. */
501 static section *
502 hot_function_section (tree decl)
504 if (decl != NULL_TREE
505 && DECL_SECTION_NAME (decl) != NULL
506 && targetm_common.have_named_sections)
507 return get_named_section (decl, NULL, 0);
508 else
509 return text_section;
511 #endif
513 /* Return section for TEXT_SECTION_NAME if DECL or DECL_SECTION_NAME (DECL)
514 is NULL.
516 When DECL_SECTION_NAME is non-NULL and it is implicit section and
517 NAMED_SECTION_SUFFIX is non-NULL, then produce section called
518 concatenate the name with NAMED_SECTION_SUFFIX.
519 Otherwise produce "TEXT_SECTION_NAME.IMPLICIT_NAME". */
521 section *
522 get_named_text_section (tree decl,
523 const char *text_section_name,
524 const char *named_section_suffix)
526 if (decl && DECL_SECTION_NAME (decl))
528 if (named_section_suffix)
530 const char *dsn = DECL_SECTION_NAME (decl);
531 const char *stripped_name;
532 char *name, *buffer;
534 name = (char *) alloca (strlen (dsn) + 1);
535 memcpy (name, dsn,
536 strlen (dsn) + 1);
538 stripped_name = targetm.strip_name_encoding (name);
540 buffer = ACONCAT ((stripped_name, named_section_suffix, NULL));
541 return get_named_section (decl, buffer, 0);
543 else if (symtab_node::get (decl)->implicit_section)
545 const char *name;
547 /* Do not try to split gnu_linkonce functions. This gets somewhat
548 slipperly. */
549 if (DECL_COMDAT_GROUP (decl) && !HAVE_COMDAT_GROUP)
550 return NULL;
551 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
552 name = targetm.strip_name_encoding (name);
553 return get_named_section (decl, ACONCAT ((text_section_name, ".",
554 name, NULL)), 0);
556 else
557 return NULL;
559 return get_named_section (decl, text_section_name, 0);
562 /* Choose named function section based on its frequency. */
564 section *
565 default_function_section (tree decl, enum node_frequency freq,
566 bool startup, bool exit)
568 #if defined HAVE_LD_EH_GC_SECTIONS && defined HAVE_LD_EH_GC_SECTIONS_BUG
569 /* Old GNU linkers have buggy --gc-section support, which sometimes
570 results in .gcc_except_table* sections being garbage collected. */
571 if (decl
572 && symtab_node::get (decl)->implicit_section)
573 return NULL;
574 #endif
576 if (!flag_reorder_functions
577 || !targetm_common.have_named_sections)
578 return NULL;
579 /* Startup code should go to startup subsection unless it is
580 unlikely executed (this happens especially with function splitting
581 where we can split away unnecessary parts of static constructors. */
582 if (startup && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
584 /* If we do have a profile or(and) LTO phase is executed, we do not need
585 these ELF section. */
586 if (!in_lto_p || !flag_profile_values)
587 return get_named_text_section (decl, ".text.startup", NULL);
588 else
589 return NULL;
592 /* Similarly for exit. */
593 if (exit && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
594 return get_named_text_section (decl, ".text.exit", NULL);
596 /* Group cold functions together, similarly for hot code. */
597 switch (freq)
599 case NODE_FREQUENCY_UNLIKELY_EXECUTED:
600 return get_named_text_section (decl, ".text.unlikely", NULL);
601 case NODE_FREQUENCY_HOT:
602 /* If we do have a profile or(and) LTO phase is executed, we do not need
603 these ELF section. */
604 if (!in_lto_p || !flag_profile_values)
605 return get_named_text_section (decl, ".text.hot", NULL);
606 /* FALLTHRU */
607 default:
608 return NULL;
612 /* Return the section for function DECL.
614 If DECL is NULL_TREE, return the text section. We can be passed
615 NULL_TREE under some circumstances by dbxout.c at least.
617 If FORCE_COLD is true, return cold function section ignoring
618 the frequency info of cgraph_node. */
620 static section *
621 function_section_1 (tree decl, bool force_cold)
623 section *section = NULL;
624 enum node_frequency freq = NODE_FREQUENCY_NORMAL;
625 bool startup = false, exit = false;
627 if (decl)
629 struct cgraph_node *node = cgraph_node::get (decl);
631 if (node)
633 freq = node->frequency;
634 startup = node->only_called_at_startup;
635 exit = node->only_called_at_exit;
638 if (force_cold)
639 freq = NODE_FREQUENCY_UNLIKELY_EXECUTED;
641 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
642 if (decl != NULL_TREE
643 && DECL_SECTION_NAME (decl) != NULL)
645 if (targetm.asm_out.function_section)
646 section = targetm.asm_out.function_section (decl, freq,
647 startup, exit);
648 if (section)
649 return section;
650 return get_named_section (decl, NULL, 0);
652 else
653 return targetm.asm_out.select_section
654 (decl, freq == NODE_FREQUENCY_UNLIKELY_EXECUTED,
655 symtab_node::get (decl)->definition_alignment ());
656 #else
657 if (targetm.asm_out.function_section)
658 section = targetm.asm_out.function_section (decl, freq, startup, exit);
659 if (section)
660 return section;
661 return hot_function_section (decl);
662 #endif
665 /* Return the section for function DECL.
667 If DECL is NULL_TREE, return the text section. We can be passed
668 NULL_TREE under some circumstances by dbxout.c at least. */
670 section *
671 function_section (tree decl)
673 /* Handle cases where function splitting code decides
674 to put function entry point into unlikely executed section
675 despite the fact that the function itself is not cold
676 (i.e. it is called rarely but contains a hot loop that is
677 better to live in hot subsection for the code locality). */
678 return function_section_1 (decl,
679 first_function_block_is_cold);
682 /* Return the section for the current function, take IN_COLD_SECTION_P
683 into account. */
685 section *
686 current_function_section (void)
688 return function_section_1 (current_function_decl, in_cold_section_p);
691 /* Tell assembler to switch to unlikely-to-be-executed text section. */
693 section *
694 unlikely_text_section (void)
696 return function_section_1 (current_function_decl, true);
699 /* When called within a function context, return true if the function
700 has been assigned a cold text section and if SECT is that section.
701 When called outside a function context, return true if SECT is the
702 default cold section. */
704 bool
705 unlikely_text_section_p (section *sect)
707 return sect == function_section_1 (current_function_decl, true);
710 /* Switch to the other function partition (if inside of hot section
711 into cold section, otherwise into the hot section). */
713 void
714 switch_to_other_text_partition (void)
716 in_cold_section_p = !in_cold_section_p;
717 switch_to_section (current_function_section ());
720 /* Return the read-only data section associated with function DECL. */
722 section *
723 default_function_rodata_section (tree decl)
725 if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
727 const char *name = DECL_SECTION_NAME (decl);
729 if (DECL_COMDAT_GROUP (decl) && HAVE_COMDAT_GROUP)
731 const char *dot;
732 size_t len;
733 char* rname;
735 dot = strchr (name + 1, '.');
736 if (!dot)
737 dot = name;
738 len = strlen (dot) + 8;
739 rname = (char *) alloca (len);
741 strcpy (rname, ".rodata");
742 strcat (rname, dot);
743 return get_section (rname, SECTION_LINKONCE, decl);
745 /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo. */
746 else if (DECL_COMDAT_GROUP (decl)
747 && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
749 size_t len = strlen (name) + 1;
750 char *rname = (char *) alloca (len);
752 memcpy (rname, name, len);
753 rname[14] = 'r';
754 return get_section (rname, SECTION_LINKONCE, decl);
756 /* For .text.foo we want to use .rodata.foo. */
757 else if (flag_function_sections && flag_data_sections
758 && strncmp (name, ".text.", 6) == 0)
760 size_t len = strlen (name) + 1;
761 char *rname = (char *) alloca (len + 2);
763 memcpy (rname, ".rodata", 7);
764 memcpy (rname + 7, name + 5, len - 5);
765 return get_section (rname, 0, decl);
769 return readonly_data_section;
772 /* Return the read-only data section associated with function DECL
773 for targets where that section should be always the single
774 readonly data section. */
776 section *
777 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
779 return readonly_data_section;
782 /* A subroutine of mergeable_string_section and mergeable_constant_section. */
784 static const char *
785 function_mergeable_rodata_prefix (void)
787 section *s = targetm.asm_out.function_rodata_section (current_function_decl);
788 if (SECTION_STYLE (s) == SECTION_NAMED)
789 return s->named.name;
790 else
791 return targetm.asm_out.mergeable_rodata_prefix;
794 /* Return the section to use for string merging. */
796 static section *
797 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
798 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
799 unsigned int flags ATTRIBUTE_UNUSED)
801 HOST_WIDE_INT len;
803 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
804 && TREE_CODE (decl) == STRING_CST
805 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
806 && align <= 256
807 && (len = int_size_in_bytes (TREE_TYPE (decl))) > 0
808 && TREE_STRING_LENGTH (decl) >= len)
810 scalar_int_mode mode;
811 unsigned int modesize;
812 const char *str;
813 HOST_WIDE_INT i;
814 int j, unit;
815 const char *prefix = function_mergeable_rodata_prefix ();
816 char *name = (char *) alloca (strlen (prefix) + 30);
818 mode = SCALAR_INT_TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
819 modesize = GET_MODE_BITSIZE (mode);
820 if (modesize >= 8 && modesize <= 256
821 && (modesize & (modesize - 1)) == 0)
823 if (align < modesize)
824 align = modesize;
826 str = TREE_STRING_POINTER (decl);
827 unit = GET_MODE_SIZE (mode);
829 /* Check for embedded NUL characters. */
830 for (i = 0; i < len; i += unit)
832 for (j = 0; j < unit; j++)
833 if (str[i + j] != '\0')
834 break;
835 if (j == unit)
836 break;
838 if (i == len - unit)
840 sprintf (name, "%s.str%d.%d", prefix,
841 modesize / 8, (int) (align / 8));
842 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
843 return get_section (name, flags, NULL);
848 return readonly_data_section;
851 /* Return the section to use for constant merging. */
853 section *
854 mergeable_constant_section (machine_mode mode ATTRIBUTE_UNUSED,
855 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
856 unsigned int flags ATTRIBUTE_UNUSED)
858 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
859 && mode != VOIDmode
860 && mode != BLKmode
861 && known_le (GET_MODE_BITSIZE (mode), align)
862 && align >= 8
863 && align <= 256
864 && (align & (align - 1)) == 0)
866 const char *prefix = function_mergeable_rodata_prefix ();
867 char *name = (char *) alloca (strlen (prefix) + 30);
869 sprintf (name, "%s.cst%d", prefix, (int) (align / 8));
870 flags |= (align / 8) | SECTION_MERGE;
871 return get_section (name, flags, NULL);
873 return readonly_data_section;
876 /* Given NAME, a putative register name, discard any customary prefixes. */
878 static const char *
879 strip_reg_name (const char *name)
881 #ifdef REGISTER_PREFIX
882 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
883 name += strlen (REGISTER_PREFIX);
884 #endif
885 if (name[0] == '%' || name[0] == '#')
886 name++;
887 return name;
890 /* The user has asked for a DECL to have a particular name. Set (or
891 change) it in such a way that we don't prefix an underscore to
892 it. */
893 void
894 set_user_assembler_name (tree decl, const char *name)
896 char *starred = (char *) alloca (strlen (name) + 2);
897 starred[0] = '*';
898 strcpy (starred + 1, name);
899 symtab->change_decl_assembler_name (decl, get_identifier (starred));
900 SET_DECL_RTL (decl, NULL_RTX);
903 /* Decode an `asm' spec for a declaration as a register name.
904 Return the register number, or -1 if nothing specified,
905 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
906 or -3 if ASMSPEC is `cc' and is not recognized,
907 or -4 if ASMSPEC is `memory' and is not recognized.
908 Accept an exact spelling or a decimal number.
909 Prefixes such as % are optional. */
912 decode_reg_name_and_count (const char *asmspec, int *pnregs)
914 /* Presume just one register is clobbered. */
915 *pnregs = 1;
917 if (asmspec != 0)
919 int i;
921 /* Get rid of confusing prefixes. */
922 asmspec = strip_reg_name (asmspec);
924 /* Allow a decimal number as a "register name". */
925 for (i = strlen (asmspec) - 1; i >= 0; i--)
926 if (! ISDIGIT (asmspec[i]))
927 break;
928 if (asmspec[0] != 0 && i < 0)
930 i = atoi (asmspec);
931 if (i < FIRST_PSEUDO_REGISTER && i >= 0 && reg_names[i][0])
932 return i;
933 else
934 return -2;
937 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
938 if (reg_names[i][0]
939 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
940 return i;
942 #ifdef OVERLAPPING_REGISTER_NAMES
944 static const struct
946 const char *const name;
947 const int number;
948 const int nregs;
949 } table[] = OVERLAPPING_REGISTER_NAMES;
951 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
952 if (table[i].name[0]
953 && ! strcmp (asmspec, table[i].name))
955 *pnregs = table[i].nregs;
956 return table[i].number;
959 #endif /* OVERLAPPING_REGISTER_NAMES */
961 #ifdef ADDITIONAL_REGISTER_NAMES
963 static const struct { const char *const name; const int number; } table[]
964 = ADDITIONAL_REGISTER_NAMES;
966 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
967 if (table[i].name[0]
968 && ! strcmp (asmspec, table[i].name)
969 && reg_names[table[i].number][0])
970 return table[i].number;
972 #endif /* ADDITIONAL_REGISTER_NAMES */
974 if (!strcmp (asmspec, "memory"))
975 return -4;
977 if (!strcmp (asmspec, "cc"))
978 return -3;
980 return -2;
983 return -1;
987 decode_reg_name (const char *name)
989 int count;
990 return decode_reg_name_and_count (name, &count);
994 /* Return true if DECL's initializer is suitable for a BSS section. */
996 bool
997 bss_initializer_p (const_tree decl, bool named)
999 /* Do not put non-common constants into the .bss section, they belong in
1000 a readonly section, except when NAMED is true. */
1001 return ((!TREE_READONLY (decl) || DECL_COMMON (decl) || named)
1002 && (DECL_INITIAL (decl) == NULL
1003 /* In LTO we have no errors in program; error_mark_node is used
1004 to mark offlined constructors. */
1005 || (DECL_INITIAL (decl) == error_mark_node
1006 && !in_lto_p)
1007 || (flag_zero_initialized_in_bss
1008 && initializer_zerop (DECL_INITIAL (decl)))));
1011 /* Compute the alignment of variable specified by DECL.
1012 DONT_OUTPUT_DATA is from assemble_variable. */
1014 void
1015 align_variable (tree decl, bool dont_output_data)
1017 unsigned int align = DECL_ALIGN (decl);
1019 /* In the case for initialing an array whose length isn't specified,
1020 where we have not yet been able to do the layout,
1021 figure out the proper alignment now. */
1022 if (dont_output_data && DECL_SIZE (decl) == 0
1023 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
1024 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
1026 /* Some object file formats have a maximum alignment which they support.
1027 In particular, a.out format supports a maximum alignment of 4. */
1028 if (align > MAX_OFILE_ALIGNMENT)
1030 error ("alignment of %q+D is greater than maximum object "
1031 "file alignment %d", decl,
1032 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
1033 align = MAX_OFILE_ALIGNMENT;
1036 if (! DECL_USER_ALIGN (decl))
1038 #ifdef DATA_ABI_ALIGNMENT
1039 unsigned int data_abi_align
1040 = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1041 /* For backwards compatibility, don't assume the ABI alignment for
1042 TLS variables. */
1043 if (! DECL_THREAD_LOCAL_P (decl) || data_abi_align <= BITS_PER_WORD)
1044 align = data_abi_align;
1045 #endif
1047 /* On some machines, it is good to increase alignment sometimes.
1048 But as DECL_ALIGN is used both for actually emitting the variable
1049 and for code accessing the variable as guaranteed alignment, we
1050 can only increase the alignment if it is a performance optimization
1051 if the references to it must bind to the current definition. */
1052 if (decl_binds_to_current_def_p (decl)
1053 && !DECL_VIRTUAL_P (decl))
1055 #ifdef DATA_ALIGNMENT
1056 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1057 /* Don't increase alignment too much for TLS variables - TLS space
1058 is too precious. */
1059 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1060 align = data_align;
1061 #endif
1062 if (DECL_INITIAL (decl) != 0
1063 /* In LTO we have no errors in program; error_mark_node is used
1064 to mark offlined constructors. */
1065 && (in_lto_p || DECL_INITIAL (decl) != error_mark_node))
1067 unsigned int const_align
1068 = targetm.constant_alignment (DECL_INITIAL (decl), align);
1069 /* Don't increase alignment too much for TLS variables - TLS
1070 space is too precious. */
1071 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1072 align = const_align;
1077 /* Reset the alignment in case we have made it tighter, so we can benefit
1078 from it in get_pointer_alignment. */
1079 SET_DECL_ALIGN (decl, align);
1082 /* Return DECL_ALIGN (decl), possibly increased for optimization purposes
1083 beyond what align_variable returned. */
1085 static unsigned int
1086 get_variable_align (tree decl)
1088 unsigned int align = DECL_ALIGN (decl);
1090 /* For user aligned vars or static vars align_variable already did
1091 everything. */
1092 if (DECL_USER_ALIGN (decl) || !TREE_PUBLIC (decl))
1093 return align;
1095 #ifdef DATA_ABI_ALIGNMENT
1096 if (DECL_THREAD_LOCAL_P (decl))
1097 align = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1098 #endif
1100 /* For decls that bind to the current definition, align_variable
1101 did also everything, except for not assuming ABI required alignment
1102 of TLS variables. For other vars, increase the alignment here
1103 as an optimization. */
1104 if (!decl_binds_to_current_def_p (decl))
1106 /* On some machines, it is good to increase alignment sometimes. */
1107 #ifdef DATA_ALIGNMENT
1108 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1109 /* Don't increase alignment too much for TLS variables - TLS space
1110 is too precious. */
1111 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1112 align = data_align;
1113 #endif
1114 if (DECL_INITIAL (decl) != 0
1115 /* In LTO we have no errors in program; error_mark_node is used
1116 to mark offlined constructors. */
1117 && (in_lto_p || DECL_INITIAL (decl) != error_mark_node))
1119 unsigned int const_align
1120 = targetm.constant_alignment (DECL_INITIAL (decl), align);
1121 /* Don't increase alignment too much for TLS variables - TLS space
1122 is too precious. */
1123 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1124 align = const_align;
1128 return align;
1131 /* Return the section into which the given VAR_DECL or CONST_DECL
1132 should be placed. PREFER_NOSWITCH_P is true if a noswitch
1133 section should be used wherever possible. */
1135 section *
1136 get_variable_section (tree decl, bool prefer_noswitch_p)
1138 addr_space_t as = ADDR_SPACE_GENERIC;
1139 int reloc;
1140 varpool_node *vnode = varpool_node::get (decl);
1141 if (vnode)
1143 vnode = vnode->ultimate_alias_target ();
1144 decl = vnode->decl;
1147 if (TREE_TYPE (decl) != error_mark_node)
1148 as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1150 /* We need the constructor to figure out reloc flag. */
1151 if (vnode)
1152 vnode->get_constructor ();
1154 if (DECL_COMMON (decl))
1156 /* If the decl has been given an explicit section name, or it resides
1157 in a non-generic address space, then it isn't common, and shouldn't
1158 be handled as such. */
1159 gcc_assert (DECL_SECTION_NAME (decl) == NULL
1160 && ADDR_SPACE_GENERIC_P (as));
1161 if (DECL_THREAD_LOCAL_P (decl))
1162 return tls_comm_section;
1163 else if (TREE_PUBLIC (decl) && bss_initializer_p (decl))
1164 return comm_section;
1167 if (DECL_INITIAL (decl) == error_mark_node)
1168 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1169 else if (DECL_INITIAL (decl))
1170 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1171 else
1172 reloc = 0;
1174 resolve_unique_section (decl, reloc, flag_data_sections);
1175 if (IN_NAMED_SECTION (decl))
1177 section *sect = get_named_section (decl, NULL, reloc);
1179 if ((sect->common.flags & SECTION_BSS)
1180 && !bss_initializer_p (decl, true))
1182 error_at (DECL_SOURCE_LOCATION (decl),
1183 "only zero initializers are allowed in section %qs",
1184 sect->named.name);
1185 DECL_INITIAL (decl) = error_mark_node;
1187 return sect;
1190 if (ADDR_SPACE_GENERIC_P (as)
1191 && !DECL_THREAD_LOCAL_P (decl)
1192 && !(prefer_noswitch_p && targetm.have_switchable_bss_sections)
1193 && bss_initializer_p (decl))
1195 if (!TREE_PUBLIC (decl)
1196 && !((flag_sanitize & SANITIZE_ADDRESS)
1197 && asan_protect_global (decl)))
1198 return lcomm_section;
1199 if (bss_noswitch_section)
1200 return bss_noswitch_section;
1203 return targetm.asm_out.select_section (decl, reloc,
1204 get_variable_align (decl));
1207 /* Return the block into which object_block DECL should be placed. */
1209 static struct object_block *
1210 get_block_for_decl (tree decl)
1212 section *sect;
1214 if (VAR_P (decl))
1216 /* The object must be defined in this translation unit. */
1217 if (DECL_EXTERNAL (decl))
1218 return NULL;
1220 /* There's no point using object blocks for something that is
1221 isolated by definition. */
1222 if (DECL_COMDAT_GROUP (decl))
1223 return NULL;
1226 /* We can only calculate block offsets if the decl has a known
1227 constant size. */
1228 if (DECL_SIZE_UNIT (decl) == NULL)
1229 return NULL;
1230 if (!tree_fits_uhwi_p (DECL_SIZE_UNIT (decl)))
1231 return NULL;
1233 /* Find out which section should contain DECL. We cannot put it into
1234 an object block if it requires a standalone definition. */
1235 if (VAR_P (decl))
1236 align_variable (decl, 0);
1237 sect = get_variable_section (decl, true);
1238 if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
1239 return NULL;
1241 return get_block_for_section (sect);
1244 /* Make sure block symbol SYMBOL is in block BLOCK. */
1246 static void
1247 change_symbol_block (rtx symbol, struct object_block *block)
1249 if (block != SYMBOL_REF_BLOCK (symbol))
1251 gcc_assert (SYMBOL_REF_BLOCK_OFFSET (symbol) < 0);
1252 SYMBOL_REF_BLOCK (symbol) = block;
1256 /* Return true if it is possible to put DECL in an object_block. */
1258 static bool
1259 use_blocks_for_decl_p (tree decl)
1261 struct symtab_node *snode;
1263 /* Only data DECLs can be placed into object blocks. */
1264 if (!VAR_P (decl) && TREE_CODE (decl) != CONST_DECL)
1265 return false;
1267 /* DECL_INITIAL (decl) set to decl is a hack used for some decls that
1268 are never used from code directly and we never want object block handling
1269 for those. */
1270 if (DECL_INITIAL (decl) == decl)
1271 return false;
1273 /* If this decl is an alias, then we don't want to emit a
1274 definition. */
1275 if (VAR_P (decl)
1276 && (snode = symtab_node::get (decl)) != NULL
1277 && snode->alias)
1278 return false;
1280 return targetm.use_blocks_for_decl_p (decl);
1283 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS
1284 until we find an identifier that is not itself a transparent alias.
1285 Modify the alias passed to it by reference (and all aliases on the
1286 way to the ultimate target), such that they do not have to be
1287 followed again, and return the ultimate target of the alias
1288 chain. */
1290 static inline tree
1291 ultimate_transparent_alias_target (tree *alias)
1293 tree target = *alias;
1295 if (IDENTIFIER_TRANSPARENT_ALIAS (target))
1297 gcc_assert (TREE_CHAIN (target));
1298 target = ultimate_transparent_alias_target (&TREE_CHAIN (target));
1299 gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target)
1300 && ! TREE_CHAIN (target));
1301 *alias = target;
1304 return target;
1307 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
1308 have static storage duration. In other words, it should not be an
1309 automatic variable, including PARM_DECLs.
1311 There is, however, one exception: this function handles variables
1312 explicitly placed in a particular register by the user.
1314 This is never called for PARM_DECL nodes. */
1316 void
1317 make_decl_rtl (tree decl)
1319 const char *name = 0;
1320 int reg_number;
1321 tree id;
1322 rtx x;
1324 /* Check that we are not being given an automatic variable. */
1325 gcc_assert (TREE_CODE (decl) != PARM_DECL
1326 && TREE_CODE (decl) != RESULT_DECL);
1328 /* A weak alias has TREE_PUBLIC set but not the other bits. */
1329 gcc_assert (!VAR_P (decl)
1330 || TREE_STATIC (decl)
1331 || TREE_PUBLIC (decl)
1332 || DECL_EXTERNAL (decl)
1333 || DECL_REGISTER (decl));
1335 /* And that we were not given a type or a label. */
1336 gcc_assert (TREE_CODE (decl) != TYPE_DECL
1337 && TREE_CODE (decl) != LABEL_DECL);
1339 /* For a duplicate declaration, we can be called twice on the
1340 same DECL node. Don't discard the RTL already made. */
1341 if (DECL_RTL_SET_P (decl))
1343 /* If the old RTL had the wrong mode, fix the mode. */
1344 x = DECL_RTL (decl);
1345 if (GET_MODE (x) != DECL_MODE (decl))
1346 SET_DECL_RTL (decl, adjust_address_nv (x, DECL_MODE (decl), 0));
1348 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1349 return;
1351 /* ??? Another way to do this would be to maintain a hashed
1352 table of such critters. Instead of adding stuff to a DECL
1353 to give certain attributes to it, we could use an external
1354 hash map from DECL to set of attributes. */
1356 /* Let the target reassign the RTL if it wants.
1357 This is necessary, for example, when one machine specific
1358 decl attribute overrides another. */
1359 targetm.encode_section_info (decl, DECL_RTL (decl), false);
1361 /* If the symbol has a SYMBOL_REF_BLOCK field, update it based
1362 on the new decl information. */
1363 if (MEM_P (x)
1364 && GET_CODE (XEXP (x, 0)) == SYMBOL_REF
1365 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (x, 0)))
1366 change_symbol_block (XEXP (x, 0), get_block_for_decl (decl));
1368 return;
1371 /* If this variable belongs to the global constant pool, retrieve the
1372 pre-computed RTL or recompute it in LTO mode. */
1373 if (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
1375 SET_DECL_RTL (decl, output_constant_def (DECL_INITIAL (decl), 1));
1376 return;
1379 id = DECL_ASSEMBLER_NAME (decl);
1380 if (TREE_CODE (decl) == FUNCTION_DECL
1381 && cgraph_node::get (decl)
1382 && cgraph_node::get (decl)->instrumentation_clone)
1383 ultimate_transparent_alias_target (&id);
1384 name = IDENTIFIER_POINTER (id);
1386 if (name[0] != '*' && TREE_CODE (decl) != FUNCTION_DECL
1387 && DECL_REGISTER (decl))
1389 error ("register name not specified for %q+D", decl);
1391 else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1393 const char *asmspec = name+1;
1394 machine_mode mode = DECL_MODE (decl);
1395 reg_number = decode_reg_name (asmspec);
1396 /* First detect errors in declaring global registers. */
1397 if (reg_number == -1)
1398 error ("register name not specified for %q+D", decl);
1399 else if (reg_number < 0)
1400 error ("invalid register name for %q+D", decl);
1401 else if (mode == BLKmode)
1402 error ("data type of %q+D isn%'t suitable for a register",
1403 decl);
1404 else if (!in_hard_reg_set_p (accessible_reg_set, mode, reg_number))
1405 error ("the register specified for %q+D cannot be accessed"
1406 " by the current target", decl);
1407 else if (!in_hard_reg_set_p (operand_reg_set, mode, reg_number))
1408 error ("the register specified for %q+D is not general enough"
1409 " to be used as a register variable", decl);
1410 else if (!targetm.hard_regno_mode_ok (reg_number, mode))
1411 error ("register specified for %q+D isn%'t suitable for data type",
1412 decl);
1413 /* Now handle properly declared static register variables. */
1414 else
1416 int nregs;
1418 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
1420 DECL_INITIAL (decl) = 0;
1421 error ("global register variable has initial value");
1423 if (TREE_THIS_VOLATILE (decl))
1424 warning (OPT_Wvolatile_register_var,
1425 "optimization may eliminate reads and/or "
1426 "writes to register variables");
1428 /* If the user specified one of the eliminables registers here,
1429 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
1430 confused with that register and be eliminated. This usage is
1431 somewhat suspect... */
1433 SET_DECL_RTL (decl, gen_raw_REG (mode, reg_number));
1434 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
1435 REG_USERVAR_P (DECL_RTL (decl)) = 1;
1437 if (TREE_STATIC (decl))
1439 /* Make this register global, so not usable for anything
1440 else. */
1441 #ifdef ASM_DECLARE_REGISTER_GLOBAL
1442 name = IDENTIFIER_POINTER (DECL_NAME (decl));
1443 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
1444 #endif
1445 nregs = hard_regno_nregs (reg_number, mode);
1446 while (nregs > 0)
1447 globalize_reg (decl, reg_number + --nregs);
1450 /* As a register variable, it has no section. */
1451 return;
1453 /* Avoid internal errors from invalid register
1454 specifications. */
1455 SET_DECL_ASSEMBLER_NAME (decl, NULL_TREE);
1456 DECL_HARD_REGISTER (decl) = 0;
1457 /* Also avoid SSA inconsistencies by pretending this is an external
1458 decl now. */
1459 DECL_EXTERNAL (decl) = 1;
1460 return;
1462 /* Now handle ordinary static variables and functions (in memory).
1463 Also handle vars declared register invalidly. */
1464 else if (name[0] == '*')
1466 #ifdef REGISTER_PREFIX
1467 if (strlen (REGISTER_PREFIX) != 0)
1469 reg_number = decode_reg_name (name);
1470 if (reg_number >= 0 || reg_number == -3)
1471 error ("register name given for non-register variable %q+D", decl);
1473 #endif
1476 /* Specifying a section attribute on a variable forces it into a
1477 non-.bss section, and thus it cannot be common. */
1478 /* FIXME: In general this code should not be necessary because
1479 visibility pass is doing the same work. But notice_global_symbol
1480 is called early and it needs to make DECL_RTL to get the name.
1481 we take care of recomputing the DECL_RTL after visibility is changed. */
1482 if (VAR_P (decl)
1483 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl))
1484 && DECL_SECTION_NAME (decl) != NULL
1485 && DECL_INITIAL (decl) == NULL_TREE
1486 && DECL_COMMON (decl))
1487 DECL_COMMON (decl) = 0;
1489 /* Variables can't be both common and weak. */
1490 if (VAR_P (decl) && DECL_WEAK (decl))
1491 DECL_COMMON (decl) = 0;
1493 if (use_object_blocks_p () && use_blocks_for_decl_p (decl))
1494 x = create_block_symbol (name, get_block_for_decl (decl), -1);
1495 else
1497 machine_mode address_mode = Pmode;
1498 if (TREE_TYPE (decl) != error_mark_node)
1500 addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1501 address_mode = targetm.addr_space.address_mode (as);
1503 x = gen_rtx_SYMBOL_REF (address_mode, name);
1505 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
1506 SET_SYMBOL_REF_DECL (x, decl);
1508 x = gen_rtx_MEM (DECL_MODE (decl), x);
1509 if (TREE_CODE (decl) != FUNCTION_DECL)
1510 set_mem_attributes (x, decl, 1);
1511 SET_DECL_RTL (decl, x);
1513 /* Optionally set flags or add text to the name to record information
1514 such as that it is a function name.
1515 If the name is changed, the macro ASM_OUTPUT_LABELREF
1516 will have to know how to strip this information. */
1517 targetm.encode_section_info (decl, DECL_RTL (decl), true);
1520 /* Like make_decl_rtl, but inhibit creation of new alias sets when
1521 calling make_decl_rtl. Also, reset DECL_RTL before returning the
1522 rtl. */
1525 make_decl_rtl_for_debug (tree decl)
1527 unsigned int save_aliasing_flag;
1528 rtx rtl;
1530 if (DECL_RTL_SET_P (decl))
1531 return DECL_RTL (decl);
1533 /* Kludge alert! Somewhere down the call chain, make_decl_rtl will
1534 call new_alias_set. If running with -fcompare-debug, sometimes
1535 we do not want to create alias sets that will throw the alias
1536 numbers off in the comparison dumps. So... clearing
1537 flag_strict_aliasing will keep new_alias_set() from creating a
1538 new set. */
1539 save_aliasing_flag = flag_strict_aliasing;
1540 flag_strict_aliasing = 0;
1542 rtl = DECL_RTL (decl);
1543 /* Reset DECL_RTL back, as various parts of the compiler expects
1544 DECL_RTL set meaning it is actually going to be output. */
1545 SET_DECL_RTL (decl, NULL);
1547 flag_strict_aliasing = save_aliasing_flag;
1548 return rtl;
1551 /* Output a string of literal assembler code
1552 for an `asm' keyword used between functions. */
1554 void
1555 assemble_asm (tree string)
1557 const char *p;
1558 app_enable ();
1560 if (TREE_CODE (string) == ADDR_EXPR)
1561 string = TREE_OPERAND (string, 0);
1563 p = TREE_STRING_POINTER (string);
1564 fprintf (asm_out_file, "%s%s\n", p[0] == '\t' ? "" : "\t", p);
1567 /* Write the address of the entity given by SYMBOL to SEC. */
1568 void
1569 assemble_addr_to_section (rtx symbol, section *sec)
1571 switch_to_section (sec);
1572 assemble_align (POINTER_SIZE);
1573 assemble_integer (symbol, POINTER_SIZE_UNITS, POINTER_SIZE, 1);
1576 /* Return the numbered .ctors.N (if CONSTRUCTOR_P) or .dtors.N (if
1577 not) section for PRIORITY. */
1578 section *
1579 get_cdtor_priority_section (int priority, bool constructor_p)
1581 /* Buffer conservatively large enough for the full range of a 32-bit
1582 int plus the text below. */
1583 char buf[18];
1585 /* ??? This only works reliably with the GNU linker. */
1586 sprintf (buf, "%s.%.5u",
1587 constructor_p ? ".ctors" : ".dtors",
1588 /* Invert the numbering so the linker puts us in the proper
1589 order; constructors are run from right to left, and the
1590 linker sorts in increasing order. */
1591 MAX_INIT_PRIORITY - priority);
1592 return get_section (buf, SECTION_WRITE, NULL);
1595 void
1596 default_named_section_asm_out_destructor (rtx symbol, int priority)
1598 section *sec;
1600 if (priority != DEFAULT_INIT_PRIORITY)
1601 sec = get_cdtor_priority_section (priority,
1602 /*constructor_p=*/false);
1603 else
1604 sec = get_section (".dtors", SECTION_WRITE, NULL);
1606 assemble_addr_to_section (symbol, sec);
1609 #ifdef DTORS_SECTION_ASM_OP
1610 void
1611 default_dtor_section_asm_out_destructor (rtx symbol,
1612 int priority ATTRIBUTE_UNUSED)
1614 assemble_addr_to_section (symbol, dtors_section);
1616 #endif
1618 void
1619 default_named_section_asm_out_constructor (rtx symbol, int priority)
1621 section *sec;
1623 if (priority != DEFAULT_INIT_PRIORITY)
1624 sec = get_cdtor_priority_section (priority,
1625 /*constructor_p=*/true);
1626 else
1627 sec = get_section (".ctors", SECTION_WRITE, NULL);
1629 assemble_addr_to_section (symbol, sec);
1632 #ifdef CTORS_SECTION_ASM_OP
1633 void
1634 default_ctor_section_asm_out_constructor (rtx symbol,
1635 int priority ATTRIBUTE_UNUSED)
1637 assemble_addr_to_section (symbol, ctors_section);
1639 #endif
1641 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1642 a nonzero value if the constant pool should be output before the
1643 start of the function, or a zero value if the pool should output
1644 after the end of the function. The default is to put it before the
1645 start. */
1647 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1648 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1649 #endif
1651 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1652 to be output to assembler.
1653 Set first_global_object_name and weak_global_object_name as appropriate. */
1655 void
1656 notice_global_symbol (tree decl)
1658 const char **t = &first_global_object_name;
1660 if (first_global_object_name
1661 || !TREE_PUBLIC (decl)
1662 || DECL_EXTERNAL (decl)
1663 || !DECL_NAME (decl)
1664 || (VAR_P (decl) && DECL_HARD_REGISTER (decl))
1665 || (TREE_CODE (decl) != FUNCTION_DECL
1666 && (!VAR_P (decl)
1667 || (DECL_COMMON (decl)
1668 && (DECL_INITIAL (decl) == 0
1669 || DECL_INITIAL (decl) == error_mark_node)))))
1670 return;
1672 /* We win when global object is found, but it is useful to know about weak
1673 symbol as well so we can produce nicer unique names. */
1674 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl) || flag_shlib)
1675 t = &weak_global_object_name;
1677 if (!*t)
1679 tree id = DECL_ASSEMBLER_NAME (decl);
1680 ultimate_transparent_alias_target (&id);
1681 *t = ggc_strdup (targetm.strip_name_encoding (IDENTIFIER_POINTER (id)));
1685 /* If not using flag_reorder_blocks_and_partition, decide early whether the
1686 current function goes into the cold section, so that targets can use
1687 current_function_section during RTL expansion. DECL describes the
1688 function. */
1690 void
1691 decide_function_section (tree decl)
1693 first_function_block_is_cold = false;
1695 if (DECL_SECTION_NAME (decl))
1697 struct cgraph_node *node = cgraph_node::get (current_function_decl);
1698 /* Calls to function_section rely on first_function_block_is_cold
1699 being accurate. */
1700 first_function_block_is_cold = (node
1701 && node->frequency
1702 == NODE_FREQUENCY_UNLIKELY_EXECUTED);
1705 in_cold_section_p = first_function_block_is_cold;
1708 /* Get the function's name, as described by its RTL. This may be
1709 different from the DECL_NAME name used in the source file. */
1710 const char *
1711 get_fnname_from_decl (tree decl)
1713 rtx x = DECL_RTL (decl);
1714 gcc_assert (MEM_P (x));
1715 x = XEXP (x, 0);
1716 gcc_assert (GET_CODE (x) == SYMBOL_REF);
1717 return XSTR (x, 0);
1720 /* Output assembler code for the constant pool of a function and associated
1721 with defining the name of the function. DECL describes the function.
1722 NAME is the function's name. For the constant pool, we use the current
1723 constant pool data. */
1725 void
1726 assemble_start_function (tree decl, const char *fnname)
1728 int align;
1729 char tmp_label[100];
1730 bool hot_label_written = false;
1732 if (crtl->has_bb_partition)
1734 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTB", const_labelno);
1735 crtl->subsections.hot_section_label = ggc_strdup (tmp_label);
1736 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDB", const_labelno);
1737 crtl->subsections.cold_section_label = ggc_strdup (tmp_label);
1738 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTE", const_labelno);
1739 crtl->subsections.hot_section_end_label = ggc_strdup (tmp_label);
1740 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDE", const_labelno);
1741 crtl->subsections.cold_section_end_label = ggc_strdup (tmp_label);
1742 const_labelno++;
1743 cold_function_name = NULL_TREE;
1745 else
1747 crtl->subsections.hot_section_label = NULL;
1748 crtl->subsections.cold_section_label = NULL;
1749 crtl->subsections.hot_section_end_label = NULL;
1750 crtl->subsections.cold_section_end_label = NULL;
1753 /* The following code does not need preprocessing in the assembler. */
1755 app_disable ();
1757 if (CONSTANT_POOL_BEFORE_FUNCTION)
1758 output_constant_pool (fnname, decl);
1760 align = symtab_node::get (decl)->definition_alignment ();
1762 /* Make sure the not and cold text (code) sections are properly
1763 aligned. This is necessary here in the case where the function
1764 has both hot and cold sections, because we don't want to re-set
1765 the alignment when the section switch happens mid-function. */
1767 if (crtl->has_bb_partition)
1769 first_function_block_is_cold = false;
1771 switch_to_section (unlikely_text_section ());
1772 assemble_align (align);
1773 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_label);
1775 /* When the function starts with a cold section, we need to explicitly
1776 align the hot section and write out the hot section label.
1777 But if the current function is a thunk, we do not have a CFG. */
1778 if (!cfun->is_thunk
1779 && BB_PARTITION (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) == BB_COLD_PARTITION)
1781 switch_to_section (text_section);
1782 assemble_align (align);
1783 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1784 hot_label_written = true;
1785 first_function_block_is_cold = true;
1787 in_cold_section_p = first_function_block_is_cold;
1791 /* Switch to the correct text section for the start of the function. */
1793 switch_to_section (function_section (decl));
1794 if (crtl->has_bb_partition && !hot_label_written)
1795 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1797 /* Tell assembler to move to target machine's alignment for functions. */
1798 align = floor_log2 (align / BITS_PER_UNIT);
1799 if (align > 0)
1801 ASM_OUTPUT_ALIGN (asm_out_file, align);
1804 /* Handle a user-specified function alignment.
1805 Note that we still need to align to DECL_ALIGN, as above,
1806 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1807 if (! DECL_USER_ALIGN (decl)
1808 && align_functions_log > align
1809 && optimize_function_for_speed_p (cfun))
1811 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1812 int align_log = align_functions_log;
1813 #endif
1814 int max_skip = align_functions - 1;
1815 if (flag_limit_function_alignment && crtl->max_insn_address > 0
1816 && max_skip >= crtl->max_insn_address)
1817 max_skip = crtl->max_insn_address - 1;
1819 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1820 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file, align_log, max_skip);
1821 #else
1822 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1823 #endif
1826 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1827 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1828 #endif
1830 if (!DECL_IGNORED_P (decl))
1831 (*debug_hooks->begin_function) (decl);
1833 /* Make function name accessible from other files, if appropriate. */
1835 if (TREE_PUBLIC (decl)
1836 || (cgraph_node::get (decl)->instrumentation_clone
1837 && cgraph_node::get (decl)->instrumented_version
1838 && TREE_PUBLIC (cgraph_node::get (decl)->instrumented_version->decl)))
1840 notice_global_symbol (decl);
1842 globalize_decl (decl);
1844 maybe_assemble_visibility (decl);
1847 if (DECL_PRESERVE_P (decl))
1848 targetm.asm_out.mark_decl_preserved (fnname);
1850 unsigned HOST_WIDE_INT patch_area_size = function_entry_patch_area_size;
1851 unsigned HOST_WIDE_INT patch_area_entry = function_entry_patch_area_start;
1853 tree patchable_function_entry_attr
1854 = lookup_attribute ("patchable_function_entry", DECL_ATTRIBUTES (decl));
1855 if (patchable_function_entry_attr)
1857 tree pp_val = TREE_VALUE (patchable_function_entry_attr);
1858 tree patchable_function_entry_value1 = TREE_VALUE (pp_val);
1860 if (tree_fits_uhwi_p (patchable_function_entry_value1))
1861 patch_area_size = tree_to_uhwi (patchable_function_entry_value1);
1862 else
1863 gcc_unreachable ();
1865 patch_area_entry = 0;
1866 if (list_length (pp_val) > 1)
1868 tree patchable_function_entry_value2 =
1869 TREE_VALUE (TREE_CHAIN (pp_val));
1871 if (tree_fits_uhwi_p (patchable_function_entry_value2))
1872 patch_area_entry = tree_to_uhwi (patchable_function_entry_value2);
1873 else
1874 gcc_unreachable ();
1878 if (patch_area_entry > patch_area_size)
1880 if (patch_area_size > 0)
1881 warning (OPT_Wattributes, "Patchable function entry > size");
1882 patch_area_entry = 0;
1885 /* Emit the patching area before the entry label, if any. */
1886 if (patch_area_entry > 0)
1887 targetm.asm_out.print_patchable_function_entry (asm_out_file,
1888 patch_area_entry, true);
1890 /* Do any machine/system dependent processing of the function name. */
1891 #ifdef ASM_DECLARE_FUNCTION_NAME
1892 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1893 #else
1894 /* Standard thing is just output label for the function. */
1895 ASM_OUTPUT_FUNCTION_LABEL (asm_out_file, fnname, current_function_decl);
1896 #endif /* ASM_DECLARE_FUNCTION_NAME */
1898 /* And the area after the label. Record it if we haven't done so yet. */
1899 if (patch_area_size > patch_area_entry)
1900 targetm.asm_out.print_patchable_function_entry (asm_out_file,
1901 patch_area_size-patch_area_entry,
1902 patch_area_entry == 0);
1904 if (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (decl)))
1905 saw_no_split_stack = true;
1908 /* Output assembler code associated with defining the size of the
1909 function. DECL describes the function. NAME is the function's name. */
1911 void
1912 assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED)
1914 #ifdef ASM_DECLARE_FUNCTION_SIZE
1915 /* We could have switched section in the middle of the function. */
1916 if (crtl->has_bb_partition)
1917 switch_to_section (function_section (decl));
1918 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1919 #endif
1920 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1922 output_constant_pool (fnname, decl);
1923 switch_to_section (function_section (decl)); /* need to switch back */
1925 /* Output labels for end of hot/cold text sections (to be used by
1926 debug info.) */
1927 if (crtl->has_bb_partition)
1929 section *save_text_section;
1931 save_text_section = in_section;
1932 switch_to_section (unlikely_text_section ());
1933 #ifdef ASM_DECLARE_COLD_FUNCTION_SIZE
1934 if (cold_function_name != NULL_TREE)
1935 ASM_DECLARE_COLD_FUNCTION_SIZE (asm_out_file,
1936 IDENTIFIER_POINTER (cold_function_name),
1937 decl);
1938 #endif
1939 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label);
1940 if (first_function_block_is_cold)
1941 switch_to_section (text_section);
1942 else
1943 switch_to_section (function_section (decl));
1944 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label);
1945 switch_to_section (save_text_section);
1949 /* Assemble code to leave SIZE bytes of zeros. */
1951 void
1952 assemble_zeros (unsigned HOST_WIDE_INT size)
1954 /* Do no output if -fsyntax-only. */
1955 if (flag_syntax_only)
1956 return;
1958 #ifdef ASM_NO_SKIP_IN_TEXT
1959 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1960 so we must output 0s explicitly in the text section. */
1961 if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0)
1963 unsigned HOST_WIDE_INT i;
1964 for (i = 0; i < size; i++)
1965 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1967 else
1968 #endif
1969 if (size > 0)
1970 ASM_OUTPUT_SKIP (asm_out_file, size);
1973 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1975 void
1976 assemble_align (int align)
1978 if (align > BITS_PER_UNIT)
1980 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1984 /* Assemble a string constant with the specified C string as contents. */
1986 void
1987 assemble_string (const char *p, int size)
1989 int pos = 0;
1990 int maximum = 2000;
1992 /* If the string is very long, split it up. */
1994 while (pos < size)
1996 int thissize = size - pos;
1997 if (thissize > maximum)
1998 thissize = maximum;
2000 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
2002 pos += thissize;
2003 p += thissize;
2008 /* A noswitch_section_callback for lcomm_section. */
2010 static bool
2011 emit_local (tree decl ATTRIBUTE_UNUSED,
2012 const char *name ATTRIBUTE_UNUSED,
2013 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2014 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2016 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
2017 unsigned int align = symtab_node::get (decl)->definition_alignment ();
2018 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name,
2019 size, align);
2020 return true;
2021 #elif defined ASM_OUTPUT_ALIGNED_LOCAL
2022 unsigned int align = symtab_node::get (decl)->definition_alignment ();
2023 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, align);
2024 return true;
2025 #else
2026 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2027 return false;
2028 #endif
2031 /* A noswitch_section_callback for bss_noswitch_section. */
2033 #if defined ASM_OUTPUT_ALIGNED_BSS
2034 static bool
2035 emit_bss (tree decl ATTRIBUTE_UNUSED,
2036 const char *name ATTRIBUTE_UNUSED,
2037 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2038 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2040 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size,
2041 get_variable_align (decl));
2042 return true;
2044 #endif
2046 /* A noswitch_section_callback for comm_section. */
2048 static bool
2049 emit_common (tree decl ATTRIBUTE_UNUSED,
2050 const char *name ATTRIBUTE_UNUSED,
2051 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2052 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2054 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
2055 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name,
2056 size, get_variable_align (decl));
2057 return true;
2058 #elif defined ASM_OUTPUT_ALIGNED_COMMON
2059 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size,
2060 get_variable_align (decl));
2061 return true;
2062 #else
2063 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
2064 return false;
2065 #endif
2068 /* A noswitch_section_callback for tls_comm_section. */
2070 static bool
2071 emit_tls_common (tree decl ATTRIBUTE_UNUSED,
2072 const char *name ATTRIBUTE_UNUSED,
2073 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
2074 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
2076 #ifdef ASM_OUTPUT_TLS_COMMON
2077 ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size);
2078 return true;
2079 #else
2080 sorry ("thread-local COMMON data not implemented");
2081 return true;
2082 #endif
2085 /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT.
2086 NAME is the name of DECL's SYMBOL_REF. */
2088 static void
2089 assemble_noswitch_variable (tree decl, const char *name, section *sect,
2090 unsigned int align)
2092 unsigned HOST_WIDE_INT size, rounded;
2094 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2095 rounded = size;
2097 if ((flag_sanitize & SANITIZE_ADDRESS) && asan_protect_global (decl))
2098 size += asan_red_zone_size (size);
2100 /* Don't allocate zero bytes of common,
2101 since that means "undefined external" in the linker. */
2102 if (size == 0)
2103 rounded = 1;
2105 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2106 so that each uninitialized object starts on such a boundary. */
2107 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
2108 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2109 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2111 if (!sect->noswitch.callback (decl, name, size, rounded)
2112 && (unsigned HOST_WIDE_INT) (align / BITS_PER_UNIT) > rounded)
2113 error ("requested alignment for %q+D is greater than "
2114 "implemented alignment of %wu", decl, rounded);
2117 /* A subroutine of assemble_variable. Output the label and contents of
2118 DECL, whose address is a SYMBOL_REF with name NAME. DONT_OUTPUT_DATA
2119 is as for assemble_variable. */
2121 static void
2122 assemble_variable_contents (tree decl, const char *name,
2123 bool dont_output_data)
2125 /* Do any machine/system dependent processing of the object. */
2126 #ifdef ASM_DECLARE_OBJECT_NAME
2127 last_assemble_variable_decl = decl;
2128 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
2129 #else
2130 /* Standard thing is just output label for the object. */
2131 ASM_OUTPUT_LABEL (asm_out_file, name);
2132 #endif /* ASM_DECLARE_OBJECT_NAME */
2134 if (!dont_output_data)
2136 /* Caller is supposed to use varpool_get_constructor when it wants
2137 to output the body. */
2138 gcc_assert (!in_lto_p || DECL_INITIAL (decl) != error_mark_node);
2139 if (DECL_INITIAL (decl)
2140 && DECL_INITIAL (decl) != error_mark_node
2141 && !initializer_zerop (DECL_INITIAL (decl)))
2142 /* Output the actual data. */
2143 output_constant (DECL_INITIAL (decl),
2144 tree_to_uhwi (DECL_SIZE_UNIT (decl)),
2145 get_variable_align (decl),
2146 false);
2147 else
2148 /* Leave space for it. */
2149 assemble_zeros (tree_to_uhwi (DECL_SIZE_UNIT (decl)));
2150 targetm.asm_out.decl_end ();
2154 /* Write out assembly for the variable DECL, which is not defined in
2155 the current translation unit. */
2156 void
2157 assemble_undefined_decl (tree decl)
2159 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
2160 targetm.asm_out.assemble_undefined_decl (asm_out_file, name, decl);
2163 /* Assemble everything that is needed for a variable or function declaration.
2164 Not used for automatic variables, and not used for function definitions.
2165 Should not be called for variables of incomplete structure type.
2167 TOP_LEVEL is nonzero if this variable has file scope.
2168 AT_END is nonzero if this is the special handling, at end of compilation,
2169 to define things that have had only tentative definitions.
2170 DONT_OUTPUT_DATA if nonzero means don't actually output the
2171 initial value (that will be done by the caller). */
2173 void
2174 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
2175 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
2177 const char *name;
2178 rtx decl_rtl, symbol;
2179 section *sect;
2180 unsigned int align;
2181 bool asan_protected = false;
2183 /* This function is supposed to handle VARIABLES. Ensure we have one. */
2184 gcc_assert (VAR_P (decl));
2186 /* Emulated TLS had better not get this far. */
2187 gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl));
2189 last_assemble_variable_decl = 0;
2191 /* Normally no need to say anything here for external references,
2192 since assemble_external is called by the language-specific code
2193 when a declaration is first seen. */
2195 if (DECL_EXTERNAL (decl))
2196 return;
2198 /* Do nothing for global register variables. */
2199 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
2201 TREE_ASM_WRITTEN (decl) = 1;
2202 return;
2205 /* If type was incomplete when the variable was declared,
2206 see if it is complete now. */
2208 if (DECL_SIZE (decl) == 0)
2209 layout_decl (decl, 0);
2211 /* Still incomplete => don't allocate it; treat the tentative defn
2212 (which is what it must have been) as an `extern' reference. */
2214 if (!dont_output_data && DECL_SIZE (decl) == 0)
2216 error ("storage size of %q+D isn%'t known", decl);
2217 TREE_ASM_WRITTEN (decl) = 1;
2218 return;
2221 /* The first declaration of a variable that comes through this function
2222 decides whether it is global (in C, has external linkage)
2223 or local (in C, has internal linkage). So do nothing more
2224 if this function has already run. */
2226 if (TREE_ASM_WRITTEN (decl))
2227 return;
2229 /* Make sure targetm.encode_section_info is invoked before we set
2230 ASM_WRITTEN. */
2231 decl_rtl = DECL_RTL (decl);
2233 TREE_ASM_WRITTEN (decl) = 1;
2235 /* Do no output if -fsyntax-only. */
2236 if (flag_syntax_only)
2237 return;
2239 if (! dont_output_data
2240 && ! valid_constant_size_p (DECL_SIZE_UNIT (decl)))
2242 error ("size of variable %q+D is too large", decl);
2243 return;
2246 gcc_assert (MEM_P (decl_rtl));
2247 gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF);
2248 symbol = XEXP (decl_rtl, 0);
2250 /* If this symbol belongs to the tree constant pool, output the constant
2251 if it hasn't already been written. */
2252 if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
2254 tree decl = SYMBOL_REF_DECL (symbol);
2255 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
2256 output_constant_def_contents (symbol);
2257 return;
2260 app_disable ();
2262 name = XSTR (symbol, 0);
2263 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
2264 notice_global_symbol (decl);
2266 /* Compute the alignment of this data. */
2268 align_variable (decl, dont_output_data);
2270 if ((flag_sanitize & SANITIZE_ADDRESS)
2271 && asan_protect_global (decl))
2273 asan_protected = true;
2274 SET_DECL_ALIGN (decl, MAX (DECL_ALIGN (decl),
2275 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT));
2278 set_mem_align (decl_rtl, DECL_ALIGN (decl));
2280 align = get_variable_align (decl);
2282 if (TREE_PUBLIC (decl))
2283 maybe_assemble_visibility (decl);
2285 if (DECL_PRESERVE_P (decl))
2286 targetm.asm_out.mark_decl_preserved (name);
2288 /* First make the assembler name(s) global if appropriate. */
2289 sect = get_variable_section (decl, false);
2290 if (TREE_PUBLIC (decl)
2291 && (sect->common.flags & SECTION_COMMON) == 0)
2292 globalize_decl (decl);
2294 /* Output any data that we will need to use the address of. */
2295 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
2296 output_addressed_constants (DECL_INITIAL (decl));
2298 /* dbxout.c needs to know this. */
2299 if (sect && (sect->common.flags & SECTION_CODE) != 0)
2300 DECL_IN_TEXT_SECTION (decl) = 1;
2302 /* If the decl is part of an object_block, make sure that the decl
2303 has been positioned within its block, but do not write out its
2304 definition yet. output_object_blocks will do that later. */
2305 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
2307 gcc_assert (!dont_output_data);
2308 place_block_symbol (symbol);
2310 else if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
2311 assemble_noswitch_variable (decl, name, sect, align);
2312 else
2314 /* Special-case handling of vtv comdat sections. */
2315 if (sect->named.name
2316 && (strcmp (sect->named.name, ".vtable_map_vars") == 0))
2317 handle_vtv_comdat_section (sect, decl);
2318 else
2319 switch_to_section (sect);
2320 if (align > BITS_PER_UNIT)
2321 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2322 assemble_variable_contents (decl, name, dont_output_data);
2323 if (asan_protected)
2325 unsigned HOST_WIDE_INT int size
2326 = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2327 assemble_zeros (asan_red_zone_size (size));
2333 /* Given a function declaration (FN_DECL), this function assembles the
2334 function into the .preinit_array section. */
2336 void
2337 assemble_vtv_preinit_initializer (tree fn_decl)
2339 section *sect;
2340 unsigned flags = SECTION_WRITE;
2341 rtx symbol = XEXP (DECL_RTL (fn_decl), 0);
2343 flags |= SECTION_NOTYPE;
2344 sect = get_section (".preinit_array", flags, fn_decl);
2345 switch_to_section (sect);
2346 assemble_addr_to_section (symbol, sect);
2349 /* Return 1 if type TYPE contains any pointers. */
2351 static int
2352 contains_pointers_p (tree type)
2354 switch (TREE_CODE (type))
2356 case POINTER_TYPE:
2357 case REFERENCE_TYPE:
2358 /* I'm not sure whether OFFSET_TYPE needs this treatment,
2359 so I'll play safe and return 1. */
2360 case OFFSET_TYPE:
2361 return 1;
2363 case RECORD_TYPE:
2364 case UNION_TYPE:
2365 case QUAL_UNION_TYPE:
2367 tree fields;
2368 /* For a type that has fields, see if the fields have pointers. */
2369 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2370 if (TREE_CODE (fields) == FIELD_DECL
2371 && contains_pointers_p (TREE_TYPE (fields)))
2372 return 1;
2373 return 0;
2376 case ARRAY_TYPE:
2377 /* An array type contains pointers if its element type does. */
2378 return contains_pointers_p (TREE_TYPE (type));
2380 default:
2381 return 0;
2385 /* We delay assemble_external processing until
2386 the compilation unit is finalized. This is the best we can do for
2387 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2388 it all the way to final. See PR 17982 for further discussion. */
2389 static GTY(()) tree pending_assemble_externals;
2391 #ifdef ASM_OUTPUT_EXTERNAL
2392 /* Some targets delay some output to final using TARGET_ASM_FILE_END.
2393 As a result, assemble_external can be called after the list of externals
2394 is processed and the pointer set destroyed. */
2395 static bool pending_assemble_externals_processed;
2397 /* Avoid O(external_decls**2) lookups in the pending_assemble_externals
2398 TREE_LIST in assemble_external. */
2399 static hash_set<tree> *pending_assemble_externals_set;
2401 /* True if DECL is a function decl for which no out-of-line copy exists.
2402 It is assumed that DECL's assembler name has been set. */
2404 static bool
2405 incorporeal_function_p (tree decl)
2407 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
2409 const char *name;
2411 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2412 && ALLOCA_FUNCTION_CODE_P (DECL_FUNCTION_CODE (decl)))
2413 return true;
2415 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2416 /* Atomic or sync builtins which have survived this far will be
2417 resolved externally and therefore are not incorporeal. */
2418 if (strncmp (name, "__builtin_", 10) == 0)
2419 return true;
2421 return false;
2424 /* Actually do the tests to determine if this is necessary, and invoke
2425 ASM_OUTPUT_EXTERNAL. */
2426 static void
2427 assemble_external_real (tree decl)
2429 rtx rtl = DECL_RTL (decl);
2431 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2432 && !SYMBOL_REF_USED (XEXP (rtl, 0))
2433 && !incorporeal_function_p (decl))
2435 /* Some systems do require some output. */
2436 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2437 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2440 #endif
2442 void
2443 process_pending_assemble_externals (void)
2445 #ifdef ASM_OUTPUT_EXTERNAL
2446 tree list;
2447 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2448 assemble_external_real (TREE_VALUE (list));
2450 pending_assemble_externals = 0;
2451 pending_assemble_externals_processed = true;
2452 delete pending_assemble_externals_set;
2453 #endif
2456 /* This TREE_LIST contains any weak symbol declarations waiting
2457 to be emitted. */
2458 static GTY(()) tree weak_decls;
2460 /* Output something to declare an external symbol to the assembler,
2461 and qualifiers such as weakness. (Most assemblers don't need
2462 extern declaration, so we normally output nothing.) Do nothing if
2463 DECL is not external. */
2465 void
2466 assemble_external (tree decl ATTRIBUTE_UNUSED)
2468 /* Make sure that the ASM_OUT_FILE is open.
2469 If it's not, we should not be calling this function. */
2470 gcc_assert (asm_out_file);
2472 /* In a perfect world, the following condition would be true.
2473 Sadly, the Go front end emit assembly *from the front end*,
2474 bypassing the call graph. See PR52739. Fix before GCC 4.8. */
2475 #if 0
2476 /* This function should only be called if we are expanding, or have
2477 expanded, to RTL.
2478 Ideally, only final.c would be calling this function, but it is
2479 not clear whether that would break things somehow. See PR 17982
2480 for further discussion. */
2481 gcc_assert (state == EXPANSION
2482 || state == FINISHED);
2483 #endif
2485 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2486 return;
2488 /* We want to output annotation for weak and external symbols at
2489 very last to check if they are references or not. */
2491 if (TARGET_SUPPORTS_WEAK
2492 && DECL_WEAK (decl)
2493 /* TREE_STATIC is a weird and abused creature which is not
2494 generally the right test for whether an entity has been
2495 locally emitted, inlined or otherwise not-really-extern, but
2496 for declarations that can be weak, it happens to be
2497 match. */
2498 && !TREE_STATIC (decl)
2499 && lookup_attribute ("weak", DECL_ATTRIBUTES (decl))
2500 && value_member (decl, weak_decls) == NULL_TREE)
2501 weak_decls = tree_cons (NULL, decl, weak_decls);
2503 #ifdef ASM_OUTPUT_EXTERNAL
2504 if (pending_assemble_externals_processed)
2506 assemble_external_real (decl);
2507 return;
2510 if (! pending_assemble_externals_set->add (decl))
2511 pending_assemble_externals = tree_cons (NULL, decl,
2512 pending_assemble_externals);
2513 #endif
2516 /* Similar, for calling a library function FUN. */
2518 void
2519 assemble_external_libcall (rtx fun)
2521 /* Declare library function name external when first used, if nec. */
2522 if (! SYMBOL_REF_USED (fun))
2524 SYMBOL_REF_USED (fun) = 1;
2525 targetm.asm_out.external_libcall (fun);
2529 /* Assemble a label named NAME. */
2531 void
2532 assemble_label (FILE *file, const char *name)
2534 ASM_OUTPUT_LABEL (file, name);
2537 /* Set the symbol_referenced flag for ID. */
2538 void
2539 mark_referenced (tree id)
2541 TREE_SYMBOL_REFERENCED (id) = 1;
2544 /* Set the symbol_referenced flag for DECL and notify callgraph. */
2545 void
2546 mark_decl_referenced (tree decl)
2548 if (TREE_CODE (decl) == FUNCTION_DECL)
2550 /* Extern inline functions don't become needed when referenced.
2551 If we know a method will be emitted in other TU and no new
2552 functions can be marked reachable, just use the external
2553 definition. */
2554 struct cgraph_node *node = cgraph_node::get_create (decl);
2555 if (!DECL_EXTERNAL (decl)
2556 && !node->definition)
2557 node->mark_force_output ();
2559 else if (VAR_P (decl))
2561 varpool_node *node = varpool_node::get_create (decl);
2562 /* C++ frontend use mark_decl_references to force COMDAT variables
2563 to be output that might appear dead otherwise. */
2564 node->force_output = true;
2566 /* else do nothing - we can get various sorts of CST nodes here,
2567 which do not need to be marked. */
2571 /* Output to FILE (an assembly file) a reference to NAME. If NAME
2572 starts with a *, the rest of NAME is output verbatim. Otherwise
2573 NAME is transformed in a target-specific way (usually by the
2574 addition of an underscore). */
2576 void
2577 assemble_name_raw (FILE *file, const char *name)
2579 if (name[0] == '*')
2580 fputs (&name[1], file);
2581 else
2582 ASM_OUTPUT_LABELREF (file, name);
2585 /* Like assemble_name_raw, but should be used when NAME might refer to
2586 an entity that is also represented as a tree (like a function or
2587 variable). If NAME does refer to such an entity, that entity will
2588 be marked as referenced. */
2590 void
2591 assemble_name (FILE *file, const char *name)
2593 const char *real_name;
2594 tree id;
2596 real_name = targetm.strip_name_encoding (name);
2598 id = maybe_get_identifier (real_name);
2599 if (id)
2601 tree id_orig = id;
2603 mark_referenced (id);
2604 ultimate_transparent_alias_target (&id);
2605 if (id != id_orig)
2606 name = IDENTIFIER_POINTER (id);
2607 gcc_assert (! TREE_CHAIN (id));
2610 assemble_name_raw (file, name);
2613 /* Allocate SIZE bytes writable static space with a gensym name
2614 and return an RTX to refer to its address. */
2617 assemble_static_space (unsigned HOST_WIDE_INT size)
2619 char name[17];
2620 const char *namestring;
2621 rtx x;
2623 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2624 ++const_labelno;
2625 namestring = ggc_strdup (name);
2627 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2628 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2630 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2631 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2632 BIGGEST_ALIGNMENT);
2633 #else
2634 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2635 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2636 #else
2638 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2639 so that each uninitialized object starts on such a boundary. */
2640 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2641 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2642 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2643 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2644 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2645 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2647 #endif
2648 #endif
2649 return x;
2652 /* Assemble the static constant template for function entry trampolines.
2653 This is done at most once per compilation.
2654 Returns an RTX for the address of the template. */
2656 static GTY(()) rtx initial_trampoline;
2659 assemble_trampoline_template (void)
2661 char label[256];
2662 const char *name;
2663 int align;
2664 rtx symbol;
2666 gcc_assert (targetm.asm_out.trampoline_template != NULL);
2668 if (initial_trampoline)
2669 return initial_trampoline;
2671 /* By default, put trampoline templates in read-only data section. */
2673 #ifdef TRAMPOLINE_SECTION
2674 switch_to_section (TRAMPOLINE_SECTION);
2675 #else
2676 switch_to_section (readonly_data_section);
2677 #endif
2679 /* Write the assembler code to define one. */
2680 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2681 if (align > 0)
2682 ASM_OUTPUT_ALIGN (asm_out_file, align);
2684 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2685 targetm.asm_out.trampoline_template (asm_out_file);
2687 /* Record the rtl to refer to it. */
2688 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2689 name = ggc_strdup (label);
2690 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2691 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2693 initial_trampoline = gen_const_mem (BLKmode, symbol);
2694 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2695 set_mem_size (initial_trampoline, TRAMPOLINE_SIZE);
2697 return initial_trampoline;
2700 /* A and B are either alignments or offsets. Return the minimum alignment
2701 that may be assumed after adding the two together. */
2703 static inline unsigned
2704 min_align (unsigned int a, unsigned int b)
2706 return least_bit_hwi (a | b);
2709 /* Return the assembler directive for creating a given kind of integer
2710 object. SIZE is the number of bytes in the object and ALIGNED_P
2711 indicates whether it is known to be aligned. Return NULL if the
2712 assembly dialect has no such directive.
2714 The returned string should be printed at the start of a new line and
2715 be followed immediately by the object's initial value. */
2717 const char *
2718 integer_asm_op (int size, int aligned_p)
2720 struct asm_int_op *ops;
2722 if (aligned_p)
2723 ops = &targetm.asm_out.aligned_op;
2724 else
2725 ops = &targetm.asm_out.unaligned_op;
2727 switch (size)
2729 case 1:
2730 return targetm.asm_out.byte_op;
2731 case 2:
2732 return ops->hi;
2733 case 4:
2734 return ops->si;
2735 case 8:
2736 return ops->di;
2737 case 16:
2738 return ops->ti;
2739 default:
2740 return NULL;
2744 /* Use directive OP to assemble an integer object X. Print OP at the
2745 start of the line, followed immediately by the value of X. */
2747 void
2748 assemble_integer_with_op (const char *op, rtx x)
2750 fputs (op, asm_out_file);
2751 output_addr_const (asm_out_file, x);
2752 fputc ('\n', asm_out_file);
2755 /* The default implementation of the asm_out.integer target hook. */
2757 bool
2758 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2759 unsigned int size ATTRIBUTE_UNUSED,
2760 int aligned_p ATTRIBUTE_UNUSED)
2762 const char *op = integer_asm_op (size, aligned_p);
2763 /* Avoid GAS bugs for large values. Specifically negative values whose
2764 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2765 if (size > UNITS_PER_WORD && size > POINTER_SIZE_UNITS)
2766 return false;
2767 return op && (assemble_integer_with_op (op, x), true);
2770 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2771 the alignment of the integer in bits. Return 1 if we were able to output
2772 the constant, otherwise 0. We must be able to output the constant,
2773 if FORCE is nonzero. */
2775 bool
2776 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2778 int aligned_p;
2780 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2782 /* See if the target hook can handle this kind of object. */
2783 if (targetm.asm_out.integer (x, size, aligned_p))
2784 return true;
2786 /* If the object is a multi-byte one, try splitting it up. Split
2787 it into words it if is multi-word, otherwise split it into bytes. */
2788 if (size > 1)
2790 machine_mode omode, imode;
2791 unsigned int subalign;
2792 unsigned int subsize, i;
2793 enum mode_class mclass;
2795 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2796 subalign = MIN (align, subsize * BITS_PER_UNIT);
2797 if (GET_CODE (x) == CONST_FIXED)
2798 mclass = GET_MODE_CLASS (GET_MODE (x));
2799 else
2800 mclass = MODE_INT;
2802 omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0).require ();
2803 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0).require ();
2805 for (i = 0; i < size; i += subsize)
2807 rtx partial = simplify_subreg (omode, x, imode, i);
2808 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2809 break;
2811 if (i == size)
2812 return true;
2814 /* If we've printed some of it, but not all of it, there's no going
2815 back now. */
2816 gcc_assert (!i);
2819 gcc_assert (!force);
2821 return false;
2824 /* Assemble the floating-point constant D into an object of size MODE. ALIGN
2825 is the alignment of the constant in bits. If REVERSE is true, D is output
2826 in reverse storage order. */
2828 void
2829 assemble_real (REAL_VALUE_TYPE d, scalar_float_mode mode, unsigned int align,
2830 bool reverse)
2832 long data[4] = {0, 0, 0, 0};
2833 int bitsize, nelts, nunits, units_per;
2834 rtx elt;
2836 /* This is hairy. We have a quantity of known size. real_to_target
2837 will put it into an array of *host* longs, 32 bits per element
2838 (even if long is more than 32 bits). We need to determine the
2839 number of array elements that are occupied (nelts) and the number
2840 of *target* min-addressable units that will be occupied in the
2841 object file (nunits). We cannot assume that 32 divides the
2842 mode's bitsize (size * BITS_PER_UNIT) evenly.
2844 size * BITS_PER_UNIT is used here to make sure that padding bits
2845 (which might appear at either end of the value; real_to_target
2846 will include the padding bits in its output array) are included. */
2848 nunits = GET_MODE_SIZE (mode);
2849 bitsize = nunits * BITS_PER_UNIT;
2850 nelts = CEIL (bitsize, 32);
2851 units_per = 32 / BITS_PER_UNIT;
2853 real_to_target (data, &d, mode);
2855 /* Put out the first word with the specified alignment. */
2856 if (reverse)
2857 elt = flip_storage_order (SImode, gen_int_mode (data[nelts - 1], SImode));
2858 else
2859 elt = GEN_INT (data[0]);
2860 assemble_integer (elt, MIN (nunits, units_per), align, 1);
2861 nunits -= units_per;
2863 /* Subsequent words need only 32-bit alignment. */
2864 align = min_align (align, 32);
2866 for (int i = 1; i < nelts; i++)
2868 if (reverse)
2869 elt = flip_storage_order (SImode,
2870 gen_int_mode (data[nelts - 1 - i], SImode));
2871 else
2872 elt = GEN_INT (data[i]);
2873 assemble_integer (elt, MIN (nunits, units_per), align, 1);
2874 nunits -= units_per;
2878 /* Given an expression EXP with a constant value,
2879 reduce it to the sum of an assembler symbol and an integer.
2880 Store them both in the structure *VALUE.
2881 EXP must be reducible. */
2883 struct addr_const {
2884 rtx base;
2885 poly_int64 offset;
2888 static void
2889 decode_addr_const (tree exp, struct addr_const *value)
2891 tree target = TREE_OPERAND (exp, 0);
2892 poly_int64 offset = 0;
2893 rtx x;
2895 while (1)
2897 poly_int64 bytepos;
2898 if (TREE_CODE (target) == COMPONENT_REF
2899 && poly_int_tree_p (byte_position (TREE_OPERAND (target, 1)),
2900 &bytepos))
2902 offset += bytepos;
2903 target = TREE_OPERAND (target, 0);
2905 else if (TREE_CODE (target) == ARRAY_REF
2906 || TREE_CODE (target) == ARRAY_RANGE_REF)
2908 /* Truncate big offset. */
2909 offset
2910 += (TREE_INT_CST_LOW (TYPE_SIZE_UNIT (TREE_TYPE (target)))
2911 * wi::to_poly_widest (TREE_OPERAND (target, 1)).force_shwi ());
2912 target = TREE_OPERAND (target, 0);
2914 else if (TREE_CODE (target) == MEM_REF
2915 && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR)
2917 offset += mem_ref_offset (target).force_shwi ();
2918 target = TREE_OPERAND (TREE_OPERAND (target, 0), 0);
2920 else if (TREE_CODE (target) == INDIRECT_REF
2921 && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR
2922 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0))
2923 == ADDR_EXPR)
2924 target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0);
2925 else
2926 break;
2929 switch (TREE_CODE (target))
2931 case VAR_DECL:
2932 case FUNCTION_DECL:
2933 x = DECL_RTL (target);
2934 break;
2936 case LABEL_DECL:
2937 x = gen_rtx_MEM (FUNCTION_MODE,
2938 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2939 break;
2941 case REAL_CST:
2942 case FIXED_CST:
2943 case STRING_CST:
2944 case COMPLEX_CST:
2945 case CONSTRUCTOR:
2946 case INTEGER_CST:
2947 x = output_constant_def (target, 1);
2948 break;
2950 case INDIRECT_REF:
2951 /* This deals with absolute addresses. */
2952 offset += tree_to_shwi (TREE_OPERAND (target, 0));
2953 x = gen_rtx_MEM (QImode,
2954 gen_rtx_SYMBOL_REF (Pmode, "origin of addresses"));
2955 break;
2957 default:
2958 gcc_unreachable ();
2961 gcc_assert (MEM_P (x));
2962 x = XEXP (x, 0);
2964 value->base = x;
2965 value->offset = offset;
2968 static GTY(()) hash_table<tree_descriptor_hasher> *const_desc_htab;
2970 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2972 /* Constant pool accessor function. */
2974 hash_table<tree_descriptor_hasher> *
2975 constant_pool_htab (void)
2977 return const_desc_htab;
2980 /* Compute a hash code for a constant expression. */
2982 hashval_t
2983 tree_descriptor_hasher::hash (constant_descriptor_tree *ptr)
2985 return ptr->hash;
2988 static hashval_t
2989 const_hash_1 (const tree exp)
2991 const char *p;
2992 hashval_t hi;
2993 int len, i;
2994 enum tree_code code = TREE_CODE (exp);
2996 /* Either set P and LEN to the address and len of something to hash and
2997 exit the switch or return a value. */
2999 switch (code)
3001 case INTEGER_CST:
3002 p = (char *) &TREE_INT_CST_ELT (exp, 0);
3003 len = TREE_INT_CST_NUNITS (exp) * sizeof (HOST_WIDE_INT);
3004 break;
3006 case REAL_CST:
3007 return real_hash (TREE_REAL_CST_PTR (exp));
3009 case FIXED_CST:
3010 return fixed_hash (TREE_FIXED_CST_PTR (exp));
3012 case STRING_CST:
3013 p = TREE_STRING_POINTER (exp);
3014 len = TREE_STRING_LENGTH (exp);
3015 break;
3017 case COMPLEX_CST:
3018 return (const_hash_1 (TREE_REALPART (exp)) * 5
3019 + const_hash_1 (TREE_IMAGPART (exp)));
3021 case VECTOR_CST:
3023 hi = 7 + VECTOR_CST_NPATTERNS (exp);
3024 hi = hi * 563 + VECTOR_CST_NELTS_PER_PATTERN (exp);
3025 unsigned int count = vector_cst_encoded_nelts (exp);
3026 for (unsigned int i = 0; i < count; ++i)
3027 hi = hi * 563 + const_hash_1 (VECTOR_CST_ENCODED_ELT (exp, i));
3028 return hi;
3031 case CONSTRUCTOR:
3033 unsigned HOST_WIDE_INT idx;
3034 tree value;
3036 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
3038 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
3039 if (value)
3040 hi = hi * 603 + const_hash_1 (value);
3042 return hi;
3045 case ADDR_EXPR:
3046 case FDESC_EXPR:
3048 struct addr_const value;
3050 decode_addr_const (exp, &value);
3051 switch (GET_CODE (value.base))
3053 case SYMBOL_REF:
3054 /* Don't hash the address of the SYMBOL_REF;
3055 only use the offset and the symbol name. */
3056 hi = value.offset.coeffs[0];
3057 p = XSTR (value.base, 0);
3058 for (i = 0; p[i] != 0; i++)
3059 hi = ((hi * 613) + (unsigned) (p[i]));
3060 break;
3062 case LABEL_REF:
3063 hi = (value.offset.coeffs[0]
3064 + CODE_LABEL_NUMBER (label_ref_label (value.base)) * 13);
3065 break;
3067 default:
3068 gcc_unreachable ();
3071 return hi;
3073 case PLUS_EXPR:
3074 case POINTER_PLUS_EXPR:
3075 case MINUS_EXPR:
3076 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
3077 + const_hash_1 (TREE_OPERAND (exp, 1)));
3079 CASE_CONVERT:
3080 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
3082 default:
3083 /* A language specific constant. Just hash the code. */
3084 return code;
3087 /* Compute hashing function. */
3088 hi = len;
3089 for (i = 0; i < len; i++)
3090 hi = ((hi * 613) + (unsigned) (p[i]));
3092 return hi;
3095 /* Wrapper of compare_constant, for the htab interface. */
3096 bool
3097 tree_descriptor_hasher::equal (constant_descriptor_tree *c1,
3098 constant_descriptor_tree *c2)
3100 if (c1->hash != c2->hash)
3101 return 0;
3102 return compare_constant (c1->value, c2->value);
3105 /* Compare t1 and t2, and return 1 only if they are known to result in
3106 the same bit pattern on output. */
3108 static int
3109 compare_constant (const tree t1, const tree t2)
3111 enum tree_code typecode;
3113 if (t1 == NULL_TREE)
3114 return t2 == NULL_TREE;
3115 if (t2 == NULL_TREE)
3116 return 0;
3118 if (TREE_CODE (t1) != TREE_CODE (t2))
3119 return 0;
3121 switch (TREE_CODE (t1))
3123 case INTEGER_CST:
3124 /* Integer constants are the same only if the same width of type. */
3125 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3126 return 0;
3127 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3128 return 0;
3129 return tree_int_cst_equal (t1, t2);
3131 case REAL_CST:
3132 /* Real constants are the same only if the same width of type. In
3133 addition to the same width, we need to check whether the modes are the
3134 same. There might be two floating point modes that are the same size
3135 but have different representations, such as the PowerPC that has 2
3136 different 128-bit floating point types (IBM extended double and IEEE
3137 128-bit floating point). */
3138 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3139 return 0;
3140 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3141 return 0;
3142 return real_identical (&TREE_REAL_CST (t1), &TREE_REAL_CST (t2));
3144 case FIXED_CST:
3145 /* Fixed constants are the same only if the same width of type. */
3146 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3147 return 0;
3149 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
3151 case STRING_CST:
3152 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3153 return 0;
3155 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
3156 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
3157 TREE_STRING_LENGTH (t1)));
3159 case COMPLEX_CST:
3160 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
3161 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
3163 case VECTOR_CST:
3165 if (VECTOR_CST_NPATTERNS (t1)
3166 != VECTOR_CST_NPATTERNS (t2))
3167 return 0;
3169 if (VECTOR_CST_NELTS_PER_PATTERN (t1)
3170 != VECTOR_CST_NELTS_PER_PATTERN (t2))
3171 return 0;
3173 unsigned int count = vector_cst_encoded_nelts (t1);
3174 for (unsigned int i = 0; i < count; ++i)
3175 if (!compare_constant (VECTOR_CST_ENCODED_ELT (t1, i),
3176 VECTOR_CST_ENCODED_ELT (t2, i)))
3177 return 0;
3179 return 1;
3182 case CONSTRUCTOR:
3184 vec<constructor_elt, va_gc> *v1, *v2;
3185 unsigned HOST_WIDE_INT idx;
3187 typecode = TREE_CODE (TREE_TYPE (t1));
3188 if (typecode != TREE_CODE (TREE_TYPE (t2)))
3189 return 0;
3191 if (typecode == ARRAY_TYPE)
3193 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
3194 /* For arrays, check that mode, size and storage order match. */
3195 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
3196 || size_1 == -1
3197 || size_1 != int_size_in_bytes (TREE_TYPE (t2))
3198 || TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (t1))
3199 != TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (t2)))
3200 return 0;
3202 else
3204 /* For record and union constructors, require exact type
3205 equality. */
3206 if (TREE_TYPE (t1) != TREE_TYPE (t2))
3207 return 0;
3210 v1 = CONSTRUCTOR_ELTS (t1);
3211 v2 = CONSTRUCTOR_ELTS (t2);
3212 if (vec_safe_length (v1) != vec_safe_length (v2))
3213 return 0;
3215 for (idx = 0; idx < vec_safe_length (v1); ++idx)
3217 constructor_elt *c1 = &(*v1)[idx];
3218 constructor_elt *c2 = &(*v2)[idx];
3220 /* Check that each value is the same... */
3221 if (!compare_constant (c1->value, c2->value))
3222 return 0;
3223 /* ... and that they apply to the same fields! */
3224 if (typecode == ARRAY_TYPE)
3226 if (!compare_constant (c1->index, c2->index))
3227 return 0;
3229 else
3231 if (c1->index != c2->index)
3232 return 0;
3236 return 1;
3239 case ADDR_EXPR:
3240 case FDESC_EXPR:
3242 struct addr_const value1, value2;
3243 enum rtx_code code;
3244 int ret;
3246 decode_addr_const (t1, &value1);
3247 decode_addr_const (t2, &value2);
3249 if (maybe_ne (value1.offset, value2.offset))
3250 return 0;
3252 code = GET_CODE (value1.base);
3253 if (code != GET_CODE (value2.base))
3254 return 0;
3256 switch (code)
3258 case SYMBOL_REF:
3259 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3260 break;
3262 case LABEL_REF:
3263 ret = (CODE_LABEL_NUMBER (label_ref_label (value1.base))
3264 == CODE_LABEL_NUMBER (label_ref_label (value2.base)));
3265 break;
3267 default:
3268 gcc_unreachable ();
3270 return ret;
3273 case PLUS_EXPR:
3274 case POINTER_PLUS_EXPR:
3275 case MINUS_EXPR:
3276 case RANGE_EXPR:
3277 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3278 && compare_constant (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3280 CASE_CONVERT:
3281 case VIEW_CONVERT_EXPR:
3282 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3284 default:
3285 return 0;
3288 gcc_unreachable ();
3291 /* Return the section into which constant EXP should be placed. */
3293 static section *
3294 get_constant_section (tree exp, unsigned int align)
3296 return targetm.asm_out.select_section (exp,
3297 compute_reloc_for_constant (exp),
3298 align);
3301 /* Return the size of constant EXP in bytes. */
3303 static HOST_WIDE_INT
3304 get_constant_size (tree exp)
3306 HOST_WIDE_INT size;
3308 size = int_size_in_bytes (TREE_TYPE (exp));
3309 if (TREE_CODE (exp) == STRING_CST)
3310 size = MAX (TREE_STRING_LENGTH (exp), size);
3311 return size;
3314 /* Subroutine of output_constant_def:
3315 No constant equal to EXP is known to have been output.
3316 Make a constant descriptor to enter EXP in the hash table.
3317 Assign the label number and construct RTL to refer to the
3318 constant's location in memory.
3319 Caller is responsible for updating the hash table. */
3321 static struct constant_descriptor_tree *
3322 build_constant_desc (tree exp)
3324 struct constant_descriptor_tree *desc;
3325 rtx symbol, rtl;
3326 char label[256];
3327 int labelno;
3328 tree decl;
3330 desc = ggc_alloc<constant_descriptor_tree> ();
3331 desc->value = exp;
3333 /* Create a string containing the label name, in LABEL. */
3334 labelno = const_labelno++;
3335 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3337 /* Construct the VAR_DECL associated with the constant. */
3338 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3339 TREE_TYPE (exp));
3340 DECL_ARTIFICIAL (decl) = 1;
3341 DECL_IGNORED_P (decl) = 1;
3342 TREE_READONLY (decl) = 1;
3343 TREE_STATIC (decl) = 1;
3344 TREE_ADDRESSABLE (decl) = 1;
3345 /* We don't set the RTL yet as this would cause varpool to assume that the
3346 variable is referenced. Moreover, it would just be dropped in LTO mode.
3347 Instead we set the flag that will be recognized in make_decl_rtl. */
3348 DECL_IN_CONSTANT_POOL (decl) = 1;
3349 DECL_INITIAL (decl) = desc->value;
3350 /* ??? targetm.constant_alignment hasn't been updated for vector types on
3351 most architectures so use DATA_ALIGNMENT as well, except for strings. */
3352 if (TREE_CODE (exp) == STRING_CST)
3353 SET_DECL_ALIGN (decl, targetm.constant_alignment (exp, DECL_ALIGN (decl)));
3354 else
3355 align_variable (decl, 0);
3357 /* Now construct the SYMBOL_REF and the MEM. */
3358 if (use_object_blocks_p ())
3360 int align = (TREE_CODE (decl) == CONST_DECL
3361 || (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
3362 ? DECL_ALIGN (decl)
3363 : symtab_node::get (decl)->definition_alignment ());
3364 section *sect = get_constant_section (exp, align);
3365 symbol = create_block_symbol (ggc_strdup (label),
3366 get_block_for_section (sect), -1);
3368 else
3369 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3370 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3371 SET_SYMBOL_REF_DECL (symbol, decl);
3372 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3374 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3375 set_mem_attributes (rtl, exp, 1);
3376 set_mem_alias_set (rtl, 0);
3378 /* Putting EXP into the literal pool might have imposed a different
3379 alignment which should be visible in the RTX as well. */
3380 set_mem_align (rtl, DECL_ALIGN (decl));
3382 /* We cannot share RTX'es in pool entries.
3383 Mark this piece of RTL as required for unsharing. */
3384 RTX_FLAG (rtl, used) = 1;
3386 /* Set flags or add text to the name to record information, such as
3387 that it is a local symbol. If the name is changed, the macro
3388 ASM_OUTPUT_LABELREF will have to know how to strip this
3389 information. This call might invalidate our local variable
3390 SYMBOL; we can't use it afterward. */
3391 targetm.encode_section_info (exp, rtl, true);
3393 desc->rtl = rtl;
3395 return desc;
3398 /* Return an rtx representing a reference to constant data in memory
3399 for the constant expression EXP.
3401 If assembler code for such a constant has already been output,
3402 return an rtx to refer to it.
3403 Otherwise, output such a constant in memory
3404 and generate an rtx for it.
3406 If DEFER is nonzero, this constant can be deferred and output only
3407 if referenced in the function after all optimizations.
3409 `const_desc_table' records which constants already have label strings. */
3412 output_constant_def (tree exp, int defer)
3414 struct constant_descriptor_tree *desc;
3415 struct constant_descriptor_tree key;
3417 /* Look up EXP in the table of constant descriptors. If we didn't find
3418 it, create a new one. */
3419 key.value = exp;
3420 key.hash = const_hash_1 (exp);
3421 constant_descriptor_tree **loc
3422 = const_desc_htab->find_slot_with_hash (&key, key.hash, INSERT);
3424 desc = *loc;
3425 if (desc == 0)
3427 desc = build_constant_desc (exp);
3428 desc->hash = key.hash;
3429 *loc = desc;
3432 maybe_output_constant_def_contents (desc, defer);
3433 return desc->rtl;
3436 /* Subroutine of output_constant_def: Decide whether or not we need to
3437 output the constant DESC now, and if so, do it. */
3438 static void
3439 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3440 int defer)
3442 rtx symbol = XEXP (desc->rtl, 0);
3443 tree exp = desc->value;
3445 if (flag_syntax_only)
3446 return;
3448 if (TREE_ASM_WRITTEN (exp))
3449 /* Already output; don't do it again. */
3450 return;
3452 /* We can always defer constants as long as the context allows
3453 doing so. */
3454 if (defer)
3456 /* Increment n_deferred_constants if it exists. It needs to be at
3457 least as large as the number of constants actually referred to
3458 by the function. If it's too small we'll stop looking too early
3459 and fail to emit constants; if it's too large we'll only look
3460 through the entire function when we could have stopped earlier. */
3461 if (cfun)
3462 n_deferred_constants++;
3463 return;
3466 output_constant_def_contents (symbol);
3469 /* Subroutine of output_constant_def_contents. Output the definition
3470 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3471 constant's alignment in bits. */
3473 static void
3474 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3476 HOST_WIDE_INT size;
3478 size = get_constant_size (exp);
3480 /* Do any machine/system dependent processing of the constant. */
3481 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3483 /* Output the value of EXP. */
3484 output_constant (exp, size, align, false);
3486 targetm.asm_out.decl_end ();
3489 /* We must output the constant data referred to by SYMBOL; do so. */
3491 static void
3492 output_constant_def_contents (rtx symbol)
3494 tree decl = SYMBOL_REF_DECL (symbol);
3495 tree exp = DECL_INITIAL (decl);
3496 bool asan_protected = false;
3498 /* Make sure any other constants whose addresses appear in EXP
3499 are assigned label numbers. */
3500 output_addressed_constants (exp);
3502 /* We are no longer deferring this constant. */
3503 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3505 if ((flag_sanitize & SANITIZE_ADDRESS)
3506 && TREE_CODE (exp) == STRING_CST
3507 && asan_protect_global (exp))
3509 asan_protected = true;
3510 SET_DECL_ALIGN (decl, MAX (DECL_ALIGN (decl),
3511 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT));
3514 /* If the constant is part of an object block, make sure that the
3515 decl has been positioned within its block, but do not write out
3516 its definition yet. output_object_blocks will do that later. */
3517 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3518 place_block_symbol (symbol);
3519 else
3521 int align = (TREE_CODE (decl) == CONST_DECL
3522 || (VAR_P (decl) && DECL_IN_CONSTANT_POOL (decl))
3523 ? DECL_ALIGN (decl)
3524 : symtab_node::get (decl)->definition_alignment ());
3525 switch_to_section (get_constant_section (exp, align));
3526 if (align > BITS_PER_UNIT)
3527 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3528 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3529 if (asan_protected)
3531 HOST_WIDE_INT size = get_constant_size (exp);
3532 assemble_zeros (asan_red_zone_size (size));
3537 /* Look up EXP in the table of constant descriptors. Return the rtl
3538 if it has been emitted, else null. */
3541 lookup_constant_def (tree exp)
3543 struct constant_descriptor_tree key;
3545 key.value = exp;
3546 key.hash = const_hash_1 (exp);
3547 constant_descriptor_tree *desc
3548 = const_desc_htab->find_with_hash (&key, key.hash);
3550 return (desc ? desc->rtl : NULL_RTX);
3553 /* Return a tree representing a reference to constant data in memory
3554 for the constant expression EXP.
3556 This is the counterpart of output_constant_def at the Tree level. */
3558 tree
3559 tree_output_constant_def (tree exp)
3561 struct constant_descriptor_tree *desc, key;
3562 tree decl;
3564 /* Look up EXP in the table of constant descriptors. If we didn't find
3565 it, create a new one. */
3566 key.value = exp;
3567 key.hash = const_hash_1 (exp);
3568 constant_descriptor_tree **loc
3569 = const_desc_htab->find_slot_with_hash (&key, key.hash, INSERT);
3571 desc = *loc;
3572 if (desc == 0)
3574 desc = build_constant_desc (exp);
3575 desc->hash = key.hash;
3576 *loc = desc;
3579 decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3580 varpool_node::finalize_decl (decl);
3581 return decl;
3584 struct GTY((chain_next ("%h.next"), for_user)) constant_descriptor_rtx {
3585 struct constant_descriptor_rtx *next;
3586 rtx mem;
3587 rtx sym;
3588 rtx constant;
3589 HOST_WIDE_INT offset;
3590 hashval_t hash;
3591 fixed_size_mode mode;
3592 unsigned int align;
3593 int labelno;
3594 int mark;
3597 struct const_rtx_desc_hasher : ggc_ptr_hash<constant_descriptor_rtx>
3599 static hashval_t hash (constant_descriptor_rtx *);
3600 static bool equal (constant_descriptor_rtx *, constant_descriptor_rtx *);
3603 /* Used in the hash tables to avoid outputting the same constant
3604 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3605 are output once per function, not once per file. */
3606 /* ??? Only a few targets need per-function constant pools. Most
3607 can use one per-file pool. Should add a targetm bit to tell the
3608 difference. */
3610 struct GTY(()) rtx_constant_pool {
3611 /* Pointers to first and last constant in pool, as ordered by offset. */
3612 struct constant_descriptor_rtx *first;
3613 struct constant_descriptor_rtx *last;
3615 /* Hash facility for making memory-constants from constant rtl-expressions.
3616 It is used on RISC machines where immediate integer arguments and
3617 constant addresses are restricted so that such constants must be stored
3618 in memory. */
3619 hash_table<const_rtx_desc_hasher> *const_rtx_htab;
3621 /* Current offset in constant pool (does not include any
3622 machine-specific header). */
3623 HOST_WIDE_INT offset;
3626 /* Hash and compare functions for const_rtx_htab. */
3628 hashval_t
3629 const_rtx_desc_hasher::hash (constant_descriptor_rtx *desc)
3631 return desc->hash;
3634 bool
3635 const_rtx_desc_hasher::equal (constant_descriptor_rtx *x,
3636 constant_descriptor_rtx *y)
3638 if (x->mode != y->mode)
3639 return 0;
3640 return rtx_equal_p (x->constant, y->constant);
3643 /* Hash one component of a constant. */
3645 static hashval_t
3646 const_rtx_hash_1 (const_rtx x)
3648 unsigned HOST_WIDE_INT hwi;
3649 machine_mode mode;
3650 enum rtx_code code;
3651 hashval_t h;
3652 int i;
3654 code = GET_CODE (x);
3655 mode = GET_MODE (x);
3656 h = (hashval_t) code * 1048573 + mode;
3658 switch (code)
3660 case CONST_INT:
3661 hwi = INTVAL (x);
3663 fold_hwi:
3665 int shift = sizeof (hashval_t) * CHAR_BIT;
3666 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3668 h ^= (hashval_t) hwi;
3669 for (i = 1; i < n; ++i)
3671 hwi >>= shift;
3672 h ^= (hashval_t) hwi;
3675 break;
3677 case CONST_WIDE_INT:
3678 hwi = 0;
3680 for (i = 0; i < CONST_WIDE_INT_NUNITS (x); i++)
3681 hwi ^= CONST_WIDE_INT_ELT (x, i);
3682 goto fold_hwi;
3685 case CONST_DOUBLE:
3686 if (TARGET_SUPPORTS_WIDE_INT == 0 && mode == VOIDmode)
3688 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3689 goto fold_hwi;
3691 else
3692 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3693 break;
3695 case CONST_FIXED:
3696 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3697 break;
3699 case SYMBOL_REF:
3700 h ^= htab_hash_string (XSTR (x, 0));
3701 break;
3703 case LABEL_REF:
3704 h = h * 251 + CODE_LABEL_NUMBER (label_ref_label (x));
3705 break;
3707 case UNSPEC:
3708 case UNSPEC_VOLATILE:
3709 h = h * 251 + XINT (x, 1);
3710 break;
3712 default:
3713 break;
3716 return h;
3719 /* Compute a hash value for X, which should be a constant. */
3721 static hashval_t
3722 const_rtx_hash (rtx x)
3724 hashval_t h = 0;
3725 subrtx_iterator::array_type array;
3726 FOR_EACH_SUBRTX (iter, array, x, ALL)
3727 h = h * 509 + const_rtx_hash_1 (*iter);
3728 return h;
3732 /* Create and return a new rtx constant pool. */
3734 static struct rtx_constant_pool *
3735 create_constant_pool (void)
3737 struct rtx_constant_pool *pool;
3739 pool = ggc_alloc<rtx_constant_pool> ();
3740 pool->const_rtx_htab = hash_table<const_rtx_desc_hasher>::create_ggc (31);
3741 pool->first = NULL;
3742 pool->last = NULL;
3743 pool->offset = 0;
3744 return pool;
3747 /* Initialize constant pool hashing for a new function. */
3749 void
3750 init_varasm_status (void)
3752 crtl->varasm.pool = create_constant_pool ();
3753 crtl->varasm.deferred_constants = 0;
3756 /* Given a MINUS expression, simplify it if both sides
3757 include the same symbol. */
3760 simplify_subtraction (rtx x)
3762 rtx r = simplify_rtx (x);
3763 return r ? r : x;
3766 /* Given a constant rtx X, make (or find) a memory constant for its value
3767 and return a MEM rtx to refer to it in memory. IN_MODE is the mode
3768 of X. */
3771 force_const_mem (machine_mode in_mode, rtx x)
3773 struct constant_descriptor_rtx *desc, tmp;
3774 struct rtx_constant_pool *pool;
3775 char label[256];
3776 rtx def, symbol;
3777 hashval_t hash;
3778 unsigned int align;
3779 constant_descriptor_rtx **slot;
3780 fixed_size_mode mode;
3782 /* We can't force variable-sized objects to memory. */
3783 if (!is_a <fixed_size_mode> (in_mode, &mode))
3784 return NULL_RTX;
3786 /* If we're not allowed to drop X into the constant pool, don't. */
3787 if (targetm.cannot_force_const_mem (mode, x))
3788 return NULL_RTX;
3790 /* Record that this function has used a constant pool entry. */
3791 crtl->uses_const_pool = 1;
3793 /* Decide which pool to use. */
3794 pool = (targetm.use_blocks_for_constant_p (mode, x)
3795 ? shared_constant_pool
3796 : crtl->varasm.pool);
3798 /* Lookup the value in the hashtable. */
3799 tmp.constant = x;
3800 tmp.mode = mode;
3801 hash = const_rtx_hash (x);
3802 slot = pool->const_rtx_htab->find_slot_with_hash (&tmp, hash, INSERT);
3803 desc = *slot;
3805 /* If the constant was already present, return its memory. */
3806 if (desc)
3807 return copy_rtx (desc->mem);
3809 /* Otherwise, create a new descriptor. */
3810 desc = ggc_alloc<constant_descriptor_rtx> ();
3811 *slot = desc;
3813 /* Align the location counter as required by EXP's data type. */
3814 machine_mode align_mode = (mode == VOIDmode ? word_mode : mode);
3815 align = targetm.static_rtx_alignment (align_mode);
3817 pool->offset += (align / BITS_PER_UNIT) - 1;
3818 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3820 desc->next = NULL;
3821 desc->constant = copy_rtx (tmp.constant);
3822 desc->offset = pool->offset;
3823 desc->hash = hash;
3824 desc->mode = mode;
3825 desc->align = align;
3826 desc->labelno = const_labelno;
3827 desc->mark = 0;
3829 pool->offset += GET_MODE_SIZE (mode);
3830 if (pool->last)
3831 pool->last->next = desc;
3832 else
3833 pool->first = pool->last = desc;
3834 pool->last = desc;
3836 /* Create a string containing the label name, in LABEL. */
3837 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3838 ++const_labelno;
3840 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3841 the constants pool. */
3842 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3844 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3845 symbol = create_block_symbol (ggc_strdup (label),
3846 get_block_for_section (sect), -1);
3848 else
3849 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3850 desc->sym = symbol;
3851 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3852 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3853 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3855 /* Construct the MEM. */
3856 desc->mem = def = gen_const_mem (mode, symbol);
3857 set_mem_align (def, align);
3859 /* If we're dropping a label to the constant pool, make sure we
3860 don't delete it. */
3861 if (GET_CODE (x) == LABEL_REF)
3862 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3864 return copy_rtx (def);
3867 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3870 get_pool_constant (const_rtx addr)
3872 return SYMBOL_REF_CONSTANT (addr)->constant;
3875 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3876 and whether it has been output or not. */
3879 get_pool_constant_mark (rtx addr, bool *pmarked)
3881 struct constant_descriptor_rtx *desc;
3883 desc = SYMBOL_REF_CONSTANT (addr);
3884 *pmarked = (desc->mark != 0);
3885 return desc->constant;
3888 /* Similar, return the mode. */
3890 fixed_size_mode
3891 get_pool_mode (const_rtx addr)
3893 return SYMBOL_REF_CONSTANT (addr)->mode;
3896 /* Return TRUE if and only if the constant pool has no entries. Note
3897 that even entries we might end up choosing not to emit are counted
3898 here, so there is the potential for missed optimizations. */
3900 bool
3901 constant_pool_empty_p (void)
3903 return crtl->varasm.pool->first == NULL;
3906 /* Worker function for output_constant_pool_1. Emit assembly for X
3907 in MODE with known alignment ALIGN. */
3909 static void
3910 output_constant_pool_2 (fixed_size_mode mode, rtx x, unsigned int align)
3912 switch (GET_MODE_CLASS (mode))
3914 case MODE_FLOAT:
3915 case MODE_DECIMAL_FLOAT:
3917 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3918 assemble_real (*CONST_DOUBLE_REAL_VALUE (x),
3919 as_a <scalar_float_mode> (mode), align, false);
3920 break;
3923 case MODE_INT:
3924 case MODE_PARTIAL_INT:
3925 case MODE_FRACT:
3926 case MODE_UFRACT:
3927 case MODE_ACCUM:
3928 case MODE_UACCUM:
3929 case MODE_POINTER_BOUNDS:
3930 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3931 break;
3933 case MODE_VECTOR_BOOL:
3935 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3937 /* Pick the smallest integer mode that contains at least one
3938 whole element. Often this is byte_mode and contains more
3939 than one element. */
3940 unsigned int nelts = GET_MODE_NUNITS (mode);
3941 unsigned int elt_bits = GET_MODE_BITSIZE (mode) / nelts;
3942 unsigned int int_bits = MAX (elt_bits, BITS_PER_UNIT);
3943 scalar_int_mode int_mode = int_mode_for_size (int_bits, 0).require ();
3945 /* Build the constant up one integer at a time. */
3946 unsigned int elts_per_int = int_bits / elt_bits;
3947 for (unsigned int i = 0; i < nelts; i += elts_per_int)
3949 unsigned HOST_WIDE_INT value = 0;
3950 unsigned int limit = MIN (nelts - i, elts_per_int);
3951 for (unsigned int j = 0; j < limit; ++j)
3952 if (INTVAL (CONST_VECTOR_ELT (x, i + j)) != 0)
3953 value |= 1 << (j * elt_bits);
3954 output_constant_pool_2 (int_mode, gen_int_mode (value, int_mode),
3955 i != 0 ? MIN (align, int_bits) : align);
3957 break;
3959 case MODE_VECTOR_FLOAT:
3960 case MODE_VECTOR_INT:
3961 case MODE_VECTOR_FRACT:
3962 case MODE_VECTOR_UFRACT:
3963 case MODE_VECTOR_ACCUM:
3964 case MODE_VECTOR_UACCUM:
3966 int i, units;
3967 scalar_mode submode = GET_MODE_INNER (mode);
3968 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3970 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3971 units = GET_MODE_NUNITS (mode);
3973 for (i = 0; i < units; i++)
3975 rtx elt = CONST_VECTOR_ELT (x, i);
3976 output_constant_pool_2 (submode, elt, i ? subalign : align);
3979 break;
3981 default:
3982 gcc_unreachable ();
3986 /* Worker function for output_constant_pool. Emit constant DESC,
3987 giving it ALIGN bits of alignment. */
3989 static void
3990 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3991 unsigned int align)
3993 rtx x, tmp;
3995 x = desc->constant;
3997 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3998 whose CODE_LABEL has been deleted. This can occur if a jump table
3999 is eliminated by optimization. If so, write a constant of zero
4000 instead. Note that this can also happen by turning the
4001 CODE_LABEL into a NOTE. */
4002 /* ??? This seems completely and utterly wrong. Certainly it's
4003 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
4004 functioning even with rtx_insn::deleted and friends. */
4006 tmp = x;
4007 switch (GET_CODE (tmp))
4009 case CONST:
4010 if (GET_CODE (XEXP (tmp, 0)) != PLUS
4011 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
4012 break;
4013 tmp = XEXP (XEXP (tmp, 0), 0);
4014 /* FALLTHRU */
4016 case LABEL_REF:
4018 rtx_insn *insn = label_ref_label (tmp);
4019 gcc_assert (!insn->deleted ());
4020 gcc_assert (!NOTE_P (insn)
4021 || NOTE_KIND (insn) != NOTE_INSN_DELETED);
4022 break;
4025 default:
4026 break;
4029 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
4030 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
4031 align, desc->labelno, done);
4032 #endif
4034 assemble_align (align);
4036 /* Output the label. */
4037 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
4039 /* Output the data.
4040 Pass actual alignment value while emitting string constant to asm code
4041 as function 'output_constant_pool_1' explicitly passes the alignment as 1
4042 assuming that the data is already aligned which prevents the generation
4043 of fix-up table entries. */
4044 output_constant_pool_2 (desc->mode, x, desc->align);
4046 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
4047 sections have proper size. */
4048 if (align > GET_MODE_BITSIZE (desc->mode)
4049 && in_section
4050 && (in_section->common.flags & SECTION_MERGE))
4051 assemble_align (align);
4053 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
4054 done:
4055 #endif
4056 return;
4059 /* Recompute the offsets of entries in POOL, and the overall size of
4060 POOL. Do this after calling mark_constant_pool to ensure that we
4061 are computing the offset values for the pool which we will actually
4062 emit. */
4064 static void
4065 recompute_pool_offsets (struct rtx_constant_pool *pool)
4067 struct constant_descriptor_rtx *desc;
4068 pool->offset = 0;
4070 for (desc = pool->first; desc ; desc = desc->next)
4071 if (desc->mark)
4073 /* Recalculate offset. */
4074 unsigned int align = desc->align;
4075 pool->offset += (align / BITS_PER_UNIT) - 1;
4076 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
4077 desc->offset = pool->offset;
4078 pool->offset += GET_MODE_SIZE (desc->mode);
4082 /* Mark all constants that are referenced by SYMBOL_REFs in X.
4083 Emit referenced deferred strings. */
4085 static void
4086 mark_constants_in_pattern (rtx insn)
4088 subrtx_iterator::array_type array;
4089 FOR_EACH_SUBRTX (iter, array, PATTERN (insn), ALL)
4091 const_rtx x = *iter;
4092 if (GET_CODE (x) == SYMBOL_REF)
4094 if (CONSTANT_POOL_ADDRESS_P (x))
4096 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
4097 if (desc->mark == 0)
4099 desc->mark = 1;
4100 iter.substitute (desc->constant);
4103 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
4105 tree decl = SYMBOL_REF_DECL (x);
4106 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
4108 n_deferred_constants--;
4109 output_constant_def_contents (CONST_CAST_RTX (x));
4116 /* Look through appropriate parts of INSN, marking all entries in the
4117 constant pool which are actually being used. Entries that are only
4118 referenced by other constants are also marked as used. Emit
4119 deferred strings that are used. */
4121 static void
4122 mark_constants (rtx_insn *insn)
4124 if (!INSN_P (insn))
4125 return;
4127 /* Insns may appear inside a SEQUENCE. Only check the patterns of
4128 insns, not any notes that may be attached. We don't want to mark
4129 a constant just because it happens to appear in a REG_EQUIV note. */
4130 if (rtx_sequence *seq = dyn_cast <rtx_sequence *> (PATTERN (insn)))
4132 int i, n = seq->len ();
4133 for (i = 0; i < n; ++i)
4135 rtx subinsn = seq->element (i);
4136 if (INSN_P (subinsn))
4137 mark_constants_in_pattern (subinsn);
4140 else
4141 mark_constants_in_pattern (insn);
4144 /* Look through the instructions for this function, and mark all the
4145 entries in POOL which are actually being used. Emit deferred constants
4146 which have indeed been used. */
4148 static void
4149 mark_constant_pool (void)
4151 rtx_insn *insn;
4153 if (!crtl->uses_const_pool && n_deferred_constants == 0)
4154 return;
4156 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4157 mark_constants (insn);
4160 /* Write all the constants in POOL. */
4162 static void
4163 output_constant_pool_contents (struct rtx_constant_pool *pool)
4165 struct constant_descriptor_rtx *desc;
4167 for (desc = pool->first; desc ; desc = desc->next)
4168 if (desc->mark)
4170 /* If the constant is part of an object_block, make sure that
4171 the constant has been positioned within its block, but do not
4172 write out its definition yet. output_object_blocks will do
4173 that later. */
4174 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
4175 && SYMBOL_REF_BLOCK (desc->sym))
4176 place_block_symbol (desc->sym);
4177 else
4179 switch_to_section (targetm.asm_out.select_rtx_section
4180 (desc->mode, desc->constant, desc->align));
4181 output_constant_pool_1 (desc, desc->align);
4186 /* Mark all constants that are used in the current function, then write
4187 out the function's private constant pool. */
4189 static void
4190 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
4191 tree fndecl ATTRIBUTE_UNUSED)
4193 struct rtx_constant_pool *pool = crtl->varasm.pool;
4195 /* It is possible for gcc to call force_const_mem and then to later
4196 discard the instructions which refer to the constant. In such a
4197 case we do not need to output the constant. */
4198 mark_constant_pool ();
4200 /* Having marked the constant pool entries we'll actually emit, we
4201 now need to rebuild the offset information, which may have become
4202 stale. */
4203 recompute_pool_offsets (pool);
4205 #ifdef ASM_OUTPUT_POOL_PROLOGUE
4206 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
4207 #endif
4209 output_constant_pool_contents (pool);
4211 #ifdef ASM_OUTPUT_POOL_EPILOGUE
4212 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
4213 #endif
4216 /* Write the contents of the shared constant pool. */
4218 void
4219 output_shared_constant_pool (void)
4221 output_constant_pool_contents (shared_constant_pool);
4224 /* Determine what kind of relocations EXP may need. */
4227 compute_reloc_for_constant (tree exp)
4229 int reloc = 0, reloc2;
4230 tree tem;
4232 switch (TREE_CODE (exp))
4234 case ADDR_EXPR:
4235 case FDESC_EXPR:
4236 /* Go inside any operations that get_inner_reference can handle and see
4237 if what's inside is a constant: no need to do anything here for
4238 addresses of variables or functions. */
4239 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4240 tem = TREE_OPERAND (tem, 0))
4243 if (TREE_CODE (tem) == MEM_REF
4244 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4246 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4247 break;
4250 if (!targetm.binds_local_p (tem))
4251 reloc |= 2;
4252 else
4253 reloc |= 1;
4254 break;
4256 case PLUS_EXPR:
4257 case POINTER_PLUS_EXPR:
4258 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4259 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4260 break;
4262 case MINUS_EXPR:
4263 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4264 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4265 /* The difference of two local labels is computable at link time. */
4266 if (reloc == 1 && reloc2 == 1)
4267 reloc = 0;
4268 else
4269 reloc |= reloc2;
4270 break;
4272 CASE_CONVERT:
4273 case VIEW_CONVERT_EXPR:
4274 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4275 break;
4277 case CONSTRUCTOR:
4279 unsigned HOST_WIDE_INT idx;
4280 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4281 if (tem != 0)
4282 reloc |= compute_reloc_for_constant (tem);
4284 break;
4286 default:
4287 break;
4289 return reloc;
4292 /* Find all the constants whose addresses are referenced inside of EXP,
4293 and make sure assembler code with a label has been output for each one.
4294 Indicate whether an ADDR_EXPR has been encountered. */
4296 static void
4297 output_addressed_constants (tree exp)
4299 tree tem;
4301 switch (TREE_CODE (exp))
4303 case ADDR_EXPR:
4304 case FDESC_EXPR:
4305 /* Go inside any operations that get_inner_reference can handle and see
4306 if what's inside is a constant: no need to do anything here for
4307 addresses of variables or functions. */
4308 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4309 tem = TREE_OPERAND (tem, 0))
4312 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4313 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4314 tem = DECL_INITIAL (tem);
4316 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4317 output_constant_def (tem, 0);
4319 if (TREE_CODE (tem) == MEM_REF)
4320 output_addressed_constants (TREE_OPERAND (tem, 0));
4321 break;
4323 case PLUS_EXPR:
4324 case POINTER_PLUS_EXPR:
4325 case MINUS_EXPR:
4326 output_addressed_constants (TREE_OPERAND (exp, 1));
4327 gcc_fallthrough ();
4329 CASE_CONVERT:
4330 case VIEW_CONVERT_EXPR:
4331 output_addressed_constants (TREE_OPERAND (exp, 0));
4332 break;
4334 case CONSTRUCTOR:
4336 unsigned HOST_WIDE_INT idx;
4337 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4338 if (tem != 0)
4339 output_addressed_constants (tem);
4341 break;
4343 default:
4344 break;
4348 /* Whether a constructor CTOR is a valid static constant initializer if all
4349 its elements are. This used to be internal to initializer_constant_valid_p
4350 and has been exposed to let other functions like categorize_ctor_elements
4351 evaluate the property while walking a constructor for other purposes. */
4353 bool
4354 constructor_static_from_elts_p (const_tree ctor)
4356 return (TREE_CONSTANT (ctor)
4357 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4358 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4359 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4362 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4363 tree *cache);
4365 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4366 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4367 which are valid when ENDTYPE is an integer of any size; in
4368 particular, this does not accept a pointer minus a constant. This
4369 returns null_pointer_node if the VALUE is an absolute constant
4370 which can be used to initialize a static variable. Otherwise it
4371 returns NULL. */
4373 static tree
4374 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4376 tree op0, op1;
4378 if (!INTEGRAL_TYPE_P (endtype))
4379 return NULL_TREE;
4381 op0 = TREE_OPERAND (value, 0);
4382 op1 = TREE_OPERAND (value, 1);
4384 /* Like STRIP_NOPS except allow the operand mode to widen. This
4385 works around a feature of fold that simplifies (int)(p1 - p2) to
4386 ((int)p1 - (int)p2) under the theory that the narrower operation
4387 is cheaper. */
4389 while (CONVERT_EXPR_P (op0)
4390 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4392 tree inner = TREE_OPERAND (op0, 0);
4393 if (inner == error_mark_node
4394 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4395 || (GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (op0)))
4396 > GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (inner)))))
4397 break;
4398 op0 = inner;
4401 while (CONVERT_EXPR_P (op1)
4402 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4404 tree inner = TREE_OPERAND (op1, 0);
4405 if (inner == error_mark_node
4406 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4407 || (GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (op1)))
4408 > GET_MODE_SIZE (SCALAR_INT_TYPE_MODE (TREE_TYPE (inner)))))
4409 break;
4410 op1 = inner;
4413 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4414 if (!op0)
4415 return NULL_TREE;
4417 op1 = initializer_constant_valid_p_1 (op1, endtype,
4418 cache ? cache + 2 : NULL);
4419 /* Both initializers must be known. */
4420 if (op1)
4422 if (op0 == op1
4423 && (op0 == null_pointer_node
4424 || TREE_CODE (value) == MINUS_EXPR))
4425 return null_pointer_node;
4427 /* Support differences between labels. */
4428 if (TREE_CODE (op0) == LABEL_DECL
4429 && TREE_CODE (op1) == LABEL_DECL)
4430 return null_pointer_node;
4432 if (TREE_CODE (op0) == STRING_CST
4433 && TREE_CODE (op1) == STRING_CST
4434 && operand_equal_p (op0, op1, 1))
4435 return null_pointer_node;
4438 return NULL_TREE;
4441 /* Helper function of initializer_constant_valid_p.
4442 Return nonzero if VALUE is a valid constant-valued expression
4443 for use in initializing a static variable; one that can be an
4444 element of a "constant" initializer.
4446 Return null_pointer_node if the value is absolute;
4447 if it is relocatable, return the variable that determines the relocation.
4448 We assume that VALUE has been folded as much as possible;
4449 therefore, we do not need to check for such things as
4450 arithmetic-combinations of integers.
4452 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4454 static tree
4455 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4457 tree ret;
4459 switch (TREE_CODE (value))
4461 case CONSTRUCTOR:
4462 if (constructor_static_from_elts_p (value))
4464 unsigned HOST_WIDE_INT idx;
4465 tree elt;
4466 bool absolute = true;
4468 if (cache && cache[0] == value)
4469 return cache[1];
4470 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4472 tree reloc;
4473 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4474 NULL);
4475 if (!reloc
4476 /* An absolute value is required with reverse SSO. */
4477 || (reloc != null_pointer_node
4478 && TYPE_REVERSE_STORAGE_ORDER (TREE_TYPE (value))
4479 && !AGGREGATE_TYPE_P (TREE_TYPE (elt))))
4481 if (cache)
4483 cache[0] = value;
4484 cache[1] = NULL_TREE;
4486 return NULL_TREE;
4488 if (reloc != null_pointer_node)
4489 absolute = false;
4491 /* For a non-absolute relocation, there is no single
4492 variable that can be "the variable that determines the
4493 relocation." */
4494 if (cache)
4496 cache[0] = value;
4497 cache[1] = absolute ? null_pointer_node : error_mark_node;
4499 return absolute ? null_pointer_node : error_mark_node;
4502 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4504 case INTEGER_CST:
4505 case VECTOR_CST:
4506 case REAL_CST:
4507 case FIXED_CST:
4508 case STRING_CST:
4509 case COMPLEX_CST:
4510 return null_pointer_node;
4512 case ADDR_EXPR:
4513 case FDESC_EXPR:
4515 tree op0 = staticp (TREE_OPERAND (value, 0));
4516 if (op0)
4518 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4519 to be a constant, this is old-skool offsetof-like nonsense. */
4520 if (TREE_CODE (op0) == INDIRECT_REF
4521 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4522 return null_pointer_node;
4523 /* Taking the address of a nested function involves a trampoline,
4524 unless we don't need or want one. */
4525 if (TREE_CODE (op0) == FUNCTION_DECL
4526 && DECL_STATIC_CHAIN (op0)
4527 && !TREE_NO_TRAMPOLINE (value))
4528 return NULL_TREE;
4529 /* "&{...}" requires a temporary to hold the constructed
4530 object. */
4531 if (TREE_CODE (op0) == CONSTRUCTOR)
4532 return NULL_TREE;
4534 return op0;
4537 case NON_LVALUE_EXPR:
4538 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4539 endtype, cache);
4541 case VIEW_CONVERT_EXPR:
4543 tree src = TREE_OPERAND (value, 0);
4544 tree src_type = TREE_TYPE (src);
4545 tree dest_type = TREE_TYPE (value);
4547 /* Allow view-conversions from aggregate to non-aggregate type only
4548 if the bit pattern is fully preserved afterwards; otherwise, the
4549 RTL expander won't be able to apply a subsequent transformation
4550 to the underlying constructor. */
4551 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4553 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4554 return initializer_constant_valid_p_1 (src, endtype, cache);
4555 else
4556 return NULL_TREE;
4559 /* Allow all other kinds of view-conversion. */
4560 return initializer_constant_valid_p_1 (src, endtype, cache);
4563 CASE_CONVERT:
4565 tree src = TREE_OPERAND (value, 0);
4566 tree src_type = TREE_TYPE (src);
4567 tree dest_type = TREE_TYPE (value);
4569 /* Allow conversions between pointer types, floating-point
4570 types, and offset types. */
4571 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4572 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4573 || (TREE_CODE (dest_type) == OFFSET_TYPE
4574 && TREE_CODE (src_type) == OFFSET_TYPE))
4575 return initializer_constant_valid_p_1 (src, endtype, cache);
4577 /* Allow length-preserving conversions between integer types. */
4578 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4579 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4580 return initializer_constant_valid_p_1 (src, endtype, cache);
4582 /* Allow conversions between other integer types only if
4583 explicit value. Don't allow sign-extension to a type larger
4584 than word and pointer, there aren't relocations that would
4585 allow to sign extend it to a wider type. */
4586 if (INTEGRAL_TYPE_P (dest_type)
4587 && INTEGRAL_TYPE_P (src_type)
4588 && (TYPE_UNSIGNED (src_type)
4589 || TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type)
4590 || TYPE_PRECISION (dest_type) <= BITS_PER_WORD
4591 || TYPE_PRECISION (dest_type) <= POINTER_SIZE))
4593 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4594 if (inner == null_pointer_node)
4595 return null_pointer_node;
4596 break;
4599 /* Allow (int) &foo provided int is as wide as a pointer. */
4600 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4601 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4602 return initializer_constant_valid_p_1 (src, endtype, cache);
4604 /* Likewise conversions from int to pointers, but also allow
4605 conversions from 0. */
4606 if ((POINTER_TYPE_P (dest_type)
4607 || TREE_CODE (dest_type) == OFFSET_TYPE)
4608 && INTEGRAL_TYPE_P (src_type))
4610 if (TREE_CODE (src) == INTEGER_CST
4611 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4612 return null_pointer_node;
4613 if (integer_zerop (src))
4614 return null_pointer_node;
4615 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4616 return initializer_constant_valid_p_1 (src, endtype, cache);
4619 /* Allow conversions to struct or union types if the value
4620 inside is okay. */
4621 if (TREE_CODE (dest_type) == RECORD_TYPE
4622 || TREE_CODE (dest_type) == UNION_TYPE)
4623 return initializer_constant_valid_p_1 (src, endtype, cache);
4625 break;
4627 case POINTER_PLUS_EXPR:
4628 case PLUS_EXPR:
4629 /* Any valid floating-point constants will have been folded by now;
4630 with -frounding-math we hit this with addition of two constants. */
4631 if (TREE_CODE (endtype) == REAL_TYPE)
4632 return NULL_TREE;
4633 if (cache && cache[0] == value)
4634 return cache[1];
4635 if (! INTEGRAL_TYPE_P (endtype)
4636 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4638 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4639 tree valid0
4640 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4641 endtype, ncache);
4642 tree valid1
4643 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4644 endtype, ncache + 2);
4645 /* If either term is absolute, use the other term's relocation. */
4646 if (valid0 == null_pointer_node)
4647 ret = valid1;
4648 else if (valid1 == null_pointer_node)
4649 ret = valid0;
4650 /* Support narrowing pointer differences. */
4651 else
4652 ret = narrowing_initializer_constant_valid_p (value, endtype,
4653 ncache);
4655 else
4656 /* Support narrowing pointer differences. */
4657 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4658 if (cache)
4660 cache[0] = value;
4661 cache[1] = ret;
4663 return ret;
4665 case POINTER_DIFF_EXPR:
4666 case MINUS_EXPR:
4667 if (TREE_CODE (endtype) == REAL_TYPE)
4668 return NULL_TREE;
4669 if (cache && cache[0] == value)
4670 return cache[1];
4671 if (! INTEGRAL_TYPE_P (endtype)
4672 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4674 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4675 tree valid0
4676 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4677 endtype, ncache);
4678 tree valid1
4679 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4680 endtype, ncache + 2);
4681 /* Win if second argument is absolute. */
4682 if (valid1 == null_pointer_node)
4683 ret = valid0;
4684 /* Win if both arguments have the same relocation.
4685 Then the value is absolute. */
4686 else if (valid0 == valid1 && valid0 != 0)
4687 ret = null_pointer_node;
4688 /* Since GCC guarantees that string constants are unique in the
4689 generated code, a subtraction between two copies of the same
4690 constant string is absolute. */
4691 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4692 && valid1 && TREE_CODE (valid1) == STRING_CST
4693 && operand_equal_p (valid0, valid1, 1))
4694 ret = null_pointer_node;
4695 /* Support narrowing differences. */
4696 else
4697 ret = narrowing_initializer_constant_valid_p (value, endtype,
4698 ncache);
4700 else
4701 /* Support narrowing differences. */
4702 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4703 if (cache)
4705 cache[0] = value;
4706 cache[1] = ret;
4708 return ret;
4710 default:
4711 break;
4714 return NULL_TREE;
4717 /* Return nonzero if VALUE is a valid constant-valued expression
4718 for use in initializing a static variable; one that can be an
4719 element of a "constant" initializer.
4721 Return null_pointer_node if the value is absolute;
4722 if it is relocatable, return the variable that determines the relocation.
4723 We assume that VALUE has been folded as much as possible;
4724 therefore, we do not need to check for such things as
4725 arithmetic-combinations of integers. */
4726 tree
4727 initializer_constant_valid_p (tree value, tree endtype, bool reverse)
4729 tree reloc = initializer_constant_valid_p_1 (value, endtype, NULL);
4731 /* An absolute value is required with reverse storage order. */
4732 if (reloc
4733 && reloc != null_pointer_node
4734 && reverse
4735 && !AGGREGATE_TYPE_P (endtype)
4736 && !VECTOR_TYPE_P (endtype))
4737 reloc = NULL_TREE;
4739 return reloc;
4742 /* Return true if VALUE is a valid constant-valued expression
4743 for use in initializing a static bit-field; one that can be
4744 an element of a "constant" initializer. */
4746 bool
4747 initializer_constant_valid_for_bitfield_p (tree value)
4749 /* For bitfields we support integer constants or possibly nested aggregates
4750 of such. */
4751 switch (TREE_CODE (value))
4753 case CONSTRUCTOR:
4755 unsigned HOST_WIDE_INT idx;
4756 tree elt;
4758 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4759 if (!initializer_constant_valid_for_bitfield_p (elt))
4760 return false;
4761 return true;
4764 case INTEGER_CST:
4765 case REAL_CST:
4766 return true;
4768 case VIEW_CONVERT_EXPR:
4769 case NON_LVALUE_EXPR:
4770 return
4771 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4773 default:
4774 break;
4777 return false;
4780 /* output_constructor outer state of relevance in recursive calls, typically
4781 for nested aggregate bitfields. */
4783 struct oc_outer_state {
4784 unsigned int bit_offset; /* current position in ... */
4785 int byte; /* ... the outer byte buffer. */
4788 static unsigned HOST_WIDE_INT
4789 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int, bool,
4790 oc_outer_state *);
4792 /* Output assembler code for constant EXP, with no label.
4793 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4794 Assumes output_addressed_constants has been done on EXP already.
4796 Generate at least SIZE bytes of assembler data, padding at the end
4797 with zeros if necessary. SIZE must always be specified. The returned
4798 value is the actual number of bytes of assembler data generated, which
4799 may be bigger than SIZE if the object contains a variable length field.
4801 SIZE is important for structure constructors,
4802 since trailing members may have been omitted from the constructor.
4803 It is also important for initialization of arrays from string constants
4804 since the full length of the string constant might not be wanted.
4805 It is also needed for initialization of unions, where the initializer's
4806 type is just one member, and that may not be as long as the union.
4808 There a case in which we would fail to output exactly SIZE bytes:
4809 for a structure constructor that wants to produce more than SIZE bytes.
4810 But such constructors will never be generated for any possible input.
4812 ALIGN is the alignment of the data in bits.
4814 If REVERSE is true, EXP is output in reverse storage order. */
4816 static unsigned HOST_WIDE_INT
4817 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align,
4818 bool reverse)
4820 enum tree_code code;
4821 unsigned HOST_WIDE_INT thissize;
4822 rtx cst;
4824 if (size == 0 || flag_syntax_only)
4825 return size;
4827 /* See if we're trying to initialize a pointer in a non-default mode
4828 to the address of some declaration somewhere. If the target says
4829 the mode is valid for pointers, assume the target has a way of
4830 resolving it. */
4831 if (TREE_CODE (exp) == NOP_EXPR
4832 && POINTER_TYPE_P (TREE_TYPE (exp))
4833 && targetm.addr_space.valid_pointer_mode
4834 (SCALAR_INT_TYPE_MODE (TREE_TYPE (exp)),
4835 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4837 tree saved_type = TREE_TYPE (exp);
4839 /* Peel off any intermediate conversions-to-pointer for valid
4840 pointer modes. */
4841 while (TREE_CODE (exp) == NOP_EXPR
4842 && POINTER_TYPE_P (TREE_TYPE (exp))
4843 && targetm.addr_space.valid_pointer_mode
4844 (SCALAR_INT_TYPE_MODE (TREE_TYPE (exp)),
4845 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4846 exp = TREE_OPERAND (exp, 0);
4848 /* If what we're left with is the address of something, we can
4849 convert the address to the final type and output it that
4850 way. */
4851 if (TREE_CODE (exp) == ADDR_EXPR)
4852 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4853 /* Likewise for constant ints. */
4854 else if (TREE_CODE (exp) == INTEGER_CST)
4855 exp = fold_convert (saved_type, exp);
4859 /* Eliminate any conversions since we'll be outputting the underlying
4860 constant. */
4861 while (CONVERT_EXPR_P (exp)
4862 || TREE_CODE (exp) == NON_LVALUE_EXPR
4863 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4865 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4866 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4868 /* Make sure eliminating the conversion is really a no-op, except with
4869 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4870 union types to allow for Ada unchecked unions. */
4871 if (type_size > op_size
4872 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4873 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4874 /* Keep the conversion. */
4875 break;
4876 else
4877 exp = TREE_OPERAND (exp, 0);
4880 code = TREE_CODE (TREE_TYPE (exp));
4881 thissize = int_size_in_bytes (TREE_TYPE (exp));
4883 /* Allow a constructor with no elements for any data type.
4884 This means to fill the space with zeros. */
4885 if (TREE_CODE (exp) == CONSTRUCTOR
4886 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4888 assemble_zeros (size);
4889 return size;
4892 if (TREE_CODE (exp) == FDESC_EXPR)
4894 #ifdef ASM_OUTPUT_FDESC
4895 HOST_WIDE_INT part = tree_to_shwi (TREE_OPERAND (exp, 1));
4896 tree decl = TREE_OPERAND (exp, 0);
4897 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4898 #else
4899 gcc_unreachable ();
4900 #endif
4901 return size;
4904 /* Now output the underlying data. If we've handling the padding, return.
4905 Otherwise, break and ensure SIZE is the size written. */
4906 switch (code)
4908 case BOOLEAN_TYPE:
4909 case INTEGER_TYPE:
4910 case ENUMERAL_TYPE:
4911 case POINTER_TYPE:
4912 case REFERENCE_TYPE:
4913 case OFFSET_TYPE:
4914 case FIXED_POINT_TYPE:
4915 case POINTER_BOUNDS_TYPE:
4916 case NULLPTR_TYPE:
4917 cst = expand_expr (exp, NULL_RTX, VOIDmode, EXPAND_INITIALIZER);
4918 if (reverse)
4919 cst = flip_storage_order (TYPE_MODE (TREE_TYPE (exp)), cst);
4920 if (!assemble_integer (cst, MIN (size, thissize), align, 0))
4921 error ("initializer for integer/fixed-point value is too complicated");
4922 break;
4924 case REAL_TYPE:
4925 if (TREE_CODE (exp) != REAL_CST)
4926 error ("initializer for floating value is not a floating constant");
4927 else
4928 assemble_real (TREE_REAL_CST (exp),
4929 SCALAR_FLOAT_TYPE_MODE (TREE_TYPE (exp)),
4930 align, reverse);
4931 break;
4933 case COMPLEX_TYPE:
4934 output_constant (TREE_REALPART (exp), thissize / 2, align, reverse);
4935 output_constant (TREE_IMAGPART (exp), thissize / 2,
4936 min_align (align, BITS_PER_UNIT * (thissize / 2)),
4937 reverse);
4938 break;
4940 case ARRAY_TYPE:
4941 case VECTOR_TYPE:
4942 switch (TREE_CODE (exp))
4944 case CONSTRUCTOR:
4945 return output_constructor (exp, size, align, reverse, NULL);
4946 case STRING_CST:
4947 thissize
4948 = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4949 assemble_string (TREE_STRING_POINTER (exp), thissize);
4950 break;
4951 case VECTOR_CST:
4953 scalar_mode inner = SCALAR_TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4954 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4955 int elt_size = GET_MODE_SIZE (inner);
4956 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align,
4957 reverse);
4958 thissize = elt_size;
4959 /* Static constants must have a fixed size. */
4960 unsigned int nunits = VECTOR_CST_NELTS (exp).to_constant ();
4961 for (unsigned int i = 1; i < nunits; i++)
4963 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign,
4964 reverse);
4965 thissize += elt_size;
4967 break;
4969 default:
4970 gcc_unreachable ();
4972 break;
4974 case RECORD_TYPE:
4975 case UNION_TYPE:
4976 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4977 return output_constructor (exp, size, align, reverse, NULL);
4979 case ERROR_MARK:
4980 return 0;
4982 default:
4983 gcc_unreachable ();
4986 if (size > thissize)
4987 assemble_zeros (size - thissize);
4989 return size;
4992 /* Subroutine of output_constructor, used for computing the size of
4993 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4994 type with an unspecified upper bound. */
4996 static unsigned HOST_WIDE_INT
4997 array_size_for_constructor (tree val)
4999 tree max_index;
5000 unsigned HOST_WIDE_INT cnt;
5001 tree index, value, tmp;
5002 offset_int i;
5004 /* This code used to attempt to handle string constants that are not
5005 arrays of single-bytes, but nothing else does, so there's no point in
5006 doing it here. */
5007 if (TREE_CODE (val) == STRING_CST)
5008 return TREE_STRING_LENGTH (val);
5010 max_index = NULL_TREE;
5011 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
5013 if (TREE_CODE (index) == RANGE_EXPR)
5014 index = TREE_OPERAND (index, 1);
5015 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
5016 max_index = index;
5019 if (max_index == NULL_TREE)
5020 return 0;
5022 /* Compute the total number of array elements. */
5023 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
5024 i = wi::to_offset (max_index) - wi::to_offset (tmp) + 1;
5026 /* Multiply by the array element unit size to find number of bytes. */
5027 i *= wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
5029 gcc_assert (wi::fits_uhwi_p (i));
5030 return i.to_uhwi ();
5033 /* Other datastructures + helpers for output_constructor. */
5035 /* output_constructor local state to support interaction with helpers. */
5037 struct oc_local_state {
5039 /* Received arguments. */
5040 tree exp; /* Constructor expression. */
5041 tree type; /* Type of constructor expression. */
5042 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */
5043 unsigned int align; /* Known initial alignment. */
5044 tree min_index; /* Lower bound if specified for an array. */
5046 /* Output processing state. */
5047 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */
5048 int byte; /* Part of a bitfield byte yet to be output. */
5049 int last_relative_index; /* Implicit or explicit index of the last
5050 array element output within a bitfield. */
5051 bool byte_buffer_in_use; /* Whether BYTE is in use. */
5052 bool reverse; /* Whether reverse storage order is in use. */
5054 /* Current element. */
5055 tree field; /* Current field decl in a record. */
5056 tree val; /* Current element value. */
5057 tree index; /* Current element index. */
5061 /* Helper for output_constructor. From the current LOCAL state, output a
5062 RANGE_EXPR element. */
5064 static void
5065 output_constructor_array_range (oc_local_state *local)
5067 unsigned HOST_WIDE_INT fieldsize
5068 = int_size_in_bytes (TREE_TYPE (local->type));
5070 HOST_WIDE_INT lo_index
5071 = tree_to_shwi (TREE_OPERAND (local->index, 0));
5072 HOST_WIDE_INT hi_index
5073 = tree_to_shwi (TREE_OPERAND (local->index, 1));
5074 HOST_WIDE_INT index;
5076 unsigned int align2
5077 = min_align (local->align, fieldsize * BITS_PER_UNIT);
5079 for (index = lo_index; index <= hi_index; index++)
5081 /* Output the element's initial value. */
5082 if (local->val == NULL_TREE)
5083 assemble_zeros (fieldsize);
5084 else
5085 fieldsize
5086 = output_constant (local->val, fieldsize, align2, local->reverse);
5088 /* Count its size. */
5089 local->total_bytes += fieldsize;
5093 /* Helper for output_constructor. From the current LOCAL state, output a
5094 field element that is not true bitfield or part of an outer one. */
5096 static void
5097 output_constructor_regular_field (oc_local_state *local)
5099 /* Field size and position. Since this structure is static, we know the
5100 positions are constant. */
5101 unsigned HOST_WIDE_INT fieldsize;
5102 HOST_WIDE_INT fieldpos;
5104 unsigned int align2;
5106 /* Output any buffered-up bit-fields preceding this element. */
5107 if (local->byte_buffer_in_use)
5109 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5110 local->total_bytes++;
5111 local->byte_buffer_in_use = false;
5114 if (local->index != NULL_TREE)
5116 /* Perform the index calculation in modulo arithmetic but
5117 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
5118 but we are using an unsigned sizetype. */
5119 unsigned prec = TYPE_PRECISION (sizetype);
5120 offset_int idx = wi::sext (wi::to_offset (local->index)
5121 - wi::to_offset (local->min_index), prec);
5122 fieldpos = (idx * wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (local->val))))
5123 .to_short_addr ();
5125 else if (local->field != NULL_TREE)
5126 fieldpos = int_byte_position (local->field);
5127 else
5128 fieldpos = 0;
5130 /* Advance to offset of this element.
5131 Note no alignment needed in an array, since that is guaranteed
5132 if each element has the proper size. */
5133 if (local->field != NULL_TREE || local->index != NULL_TREE)
5135 if (fieldpos > local->total_bytes)
5137 assemble_zeros (fieldpos - local->total_bytes);
5138 local->total_bytes = fieldpos;
5140 else
5141 /* Must not go backwards. */
5142 gcc_assert (fieldpos == local->total_bytes);
5145 /* Find the alignment of this element. */
5146 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
5148 /* Determine size this element should occupy. */
5149 if (local->field)
5151 fieldsize = 0;
5153 /* If this is an array with an unspecified upper bound,
5154 the initializer determines the size. */
5155 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
5156 but we cannot do this until the deprecated support for
5157 initializing zero-length array members is removed. */
5158 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
5159 && (!TYPE_DOMAIN (TREE_TYPE (local->field))
5160 || !TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field)))))
5162 fieldsize = array_size_for_constructor (local->val);
5163 /* Given a non-empty initialization, this field had better
5164 be last. Given a flexible array member, the next field
5165 on the chain is a TYPE_DECL of the enclosing struct. */
5166 const_tree next = DECL_CHAIN (local->field);
5167 gcc_assert (!fieldsize || !next || TREE_CODE (next) != FIELD_DECL);
5169 else
5170 fieldsize = tree_to_uhwi (DECL_SIZE_UNIT (local->field));
5172 else
5173 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
5175 /* Output the element's initial value. */
5176 if (local->val == NULL_TREE)
5177 assemble_zeros (fieldsize);
5178 else
5179 fieldsize
5180 = output_constant (local->val, fieldsize, align2, local->reverse);
5182 /* Count its size. */
5183 local->total_bytes += fieldsize;
5186 /* Helper for output_constructor. From the LOCAL state, output an element
5187 that is a true bitfield or part of an outer one. BIT_OFFSET is the offset
5188 from the start of a possibly ongoing outer byte buffer. */
5190 static void
5191 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
5193 /* Bit size of this element. */
5194 HOST_WIDE_INT ebitsize
5195 = (local->field
5196 ? tree_to_uhwi (DECL_SIZE (local->field))
5197 : tree_to_uhwi (TYPE_SIZE (TREE_TYPE (local->type))));
5199 /* Relative index of this element if this is an array component. */
5200 HOST_WIDE_INT relative_index
5201 = (!local->field
5202 ? (local->index
5203 ? (tree_to_shwi (local->index)
5204 - tree_to_shwi (local->min_index))
5205 : local->last_relative_index + 1)
5206 : 0);
5208 /* Bit position of this element from the start of the containing
5209 constructor. */
5210 HOST_WIDE_INT constructor_relative_ebitpos
5211 = (local->field
5212 ? int_bit_position (local->field)
5213 : ebitsize * relative_index);
5215 /* Bit position of this element from the start of a possibly ongoing
5216 outer byte buffer. */
5217 HOST_WIDE_INT byte_relative_ebitpos
5218 = bit_offset + constructor_relative_ebitpos;
5220 /* From the start of a possibly ongoing outer byte buffer, offsets to
5221 the first bit of this element and to the first bit past the end of
5222 this element. */
5223 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
5224 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
5226 local->last_relative_index = relative_index;
5228 if (local->val == NULL_TREE)
5229 local->val = integer_zero_node;
5231 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
5232 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
5233 local->val = TREE_OPERAND (local->val, 0);
5235 if (TREE_CODE (local->val) != INTEGER_CST
5236 && TREE_CODE (local->val) != CONSTRUCTOR)
5238 error ("invalid initial value for member %qE", DECL_NAME (local->field));
5239 return;
5242 /* If this field does not start in this (or next) byte, skip some bytes. */
5243 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5245 /* Output remnant of any bit field in previous bytes. */
5246 if (local->byte_buffer_in_use)
5248 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5249 local->total_bytes++;
5250 local->byte_buffer_in_use = false;
5253 /* If still not at proper byte, advance to there. */
5254 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5256 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
5257 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
5258 local->total_bytes = next_offset / BITS_PER_UNIT;
5262 /* Set up the buffer if necessary. */
5263 if (!local->byte_buffer_in_use)
5265 local->byte = 0;
5266 if (ebitsize > 0)
5267 local->byte_buffer_in_use = true;
5270 /* If this is nested constructor, recurse passing the bit offset and the
5271 pending data, then retrieve the new pending data afterwards. */
5272 if (TREE_CODE (local->val) == CONSTRUCTOR)
5274 oc_outer_state temp_state;
5275 temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5276 temp_state.byte = local->byte;
5277 local->total_bytes
5278 += output_constructor (local->val, 0, 0, local->reverse, &temp_state);
5279 local->byte = temp_state.byte;
5280 return;
5283 /* Otherwise, we must split the element into pieces that fall within
5284 separate bytes, and combine each byte with previous or following
5285 bit-fields. */
5286 while (next_offset < end_offset)
5288 int this_time;
5289 int shift;
5290 HOST_WIDE_INT value;
5291 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5292 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5294 /* Advance from byte to byte within this element when necessary. */
5295 while (next_byte != local->total_bytes)
5297 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5298 local->total_bytes++;
5299 local->byte = 0;
5302 /* Number of bits we can process at once (all part of the same byte). */
5303 this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5304 if (local->reverse ? !BYTES_BIG_ENDIAN : BYTES_BIG_ENDIAN)
5306 /* For big-endian data, take the most significant bits (of the
5307 bits that are significant) first and put them into bytes from
5308 the most significant end. */
5309 shift = end_offset - next_offset - this_time;
5311 /* Don't try to take a bunch of bits that cross
5312 the word boundary in the INTEGER_CST. We can
5313 only select bits from one element. */
5314 if ((shift / HOST_BITS_PER_WIDE_INT)
5315 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5317 const int end = shift + this_time - 1;
5318 shift = end & -HOST_BITS_PER_WIDE_INT;
5319 this_time = end - shift + 1;
5322 /* Now get the bits from the appropriate constant word. */
5323 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5324 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5326 /* Get the result. This works only when:
5327 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5328 local->byte |= (((value >> shift)
5329 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5330 << (BITS_PER_UNIT - this_time - next_bit));
5332 else
5334 /* On little-endian machines, take the least significant bits of
5335 the value first and pack them starting at the least significant
5336 bits of the bytes. */
5337 shift = next_offset - byte_relative_ebitpos;
5339 /* Don't try to take a bunch of bits that cross
5340 the word boundary in the INTEGER_CST. We can
5341 only select bits from one element. */
5342 if ((shift / HOST_BITS_PER_WIDE_INT)
5343 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5344 this_time
5345 = HOST_BITS_PER_WIDE_INT - (shift & (HOST_BITS_PER_WIDE_INT - 1));
5347 /* Now get the bits from the appropriate constant word. */
5348 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5349 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5351 /* Get the result. This works only when:
5352 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5353 local->byte |= (((value >> shift)
5354 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5355 << next_bit);
5358 next_offset += this_time;
5359 local->byte_buffer_in_use = true;
5363 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5364 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5365 caller output state of relevance in recursive invocations. */
5367 static unsigned HOST_WIDE_INT
5368 output_constructor (tree exp, unsigned HOST_WIDE_INT size, unsigned int align,
5369 bool reverse, oc_outer_state *outer)
5371 unsigned HOST_WIDE_INT cnt;
5372 constructor_elt *ce;
5373 oc_local_state local;
5375 /* Setup our local state to communicate with helpers. */
5376 local.exp = exp;
5377 local.type = TREE_TYPE (exp);
5378 local.size = size;
5379 local.align = align;
5380 if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5381 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5382 else
5383 local.min_index = integer_zero_node;
5385 local.total_bytes = 0;
5386 local.byte_buffer_in_use = outer != NULL;
5387 local.byte = outer ? outer->byte : 0;
5388 local.last_relative_index = -1;
5389 /* The storage order is specified for every aggregate type. */
5390 if (AGGREGATE_TYPE_P (local.type))
5391 local.reverse = TYPE_REVERSE_STORAGE_ORDER (local.type);
5392 else
5393 local.reverse = reverse;
5395 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5397 /* As CE goes through the elements of the constant, FIELD goes through the
5398 structure fields if the constant is a structure. If the constant is a
5399 union, we override this by getting the field from the TREE_LIST element.
5400 But the constant could also be an array. Then FIELD is zero.
5402 There is always a maximum of one element in the chain LINK for unions
5403 (even if the initializer in a source program incorrectly contains
5404 more one). */
5406 if (TREE_CODE (local.type) == RECORD_TYPE)
5407 local.field = TYPE_FIELDS (local.type);
5408 else
5409 local.field = NULL_TREE;
5411 for (cnt = 0;
5412 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5413 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5415 local.val = ce->value;
5416 local.index = NULL_TREE;
5418 /* The element in a union constructor specifies the proper field
5419 or index. */
5420 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5421 local.field = ce->index;
5423 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5424 local.index = ce->index;
5426 if (local.field && flag_verbose_asm)
5427 fprintf (asm_out_file, "%s %s:\n",
5428 ASM_COMMENT_START,
5429 DECL_NAME (local.field)
5430 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5431 : "<anonymous>");
5433 /* Eliminate the marker that makes a cast not be an lvalue. */
5434 if (local.val != NULL_TREE)
5435 STRIP_NOPS (local.val);
5437 /* Output the current element, using the appropriate helper ... */
5439 /* For an array slice not part of an outer bitfield. */
5440 if (!outer
5441 && local.index != NULL_TREE
5442 && TREE_CODE (local.index) == RANGE_EXPR)
5443 output_constructor_array_range (&local);
5445 /* For a field that is neither a true bitfield nor part of an outer one,
5446 known to be at least byte aligned and multiple-of-bytes long. */
5447 else if (!outer
5448 && (local.field == NULL_TREE
5449 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5450 output_constructor_regular_field (&local);
5452 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5453 supported for scalar fields, so we may need to convert first. */
5454 else
5456 if (TREE_CODE (local.val) == REAL_CST)
5457 local.val
5458 = fold_unary (VIEW_CONVERT_EXPR,
5459 build_nonstandard_integer_type
5460 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5461 local.val);
5462 output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5466 /* If we are not at toplevel, save the pending data for our caller.
5467 Otherwise output the pending data and padding zeros as needed. */
5468 if (outer)
5469 outer->byte = local.byte;
5470 else
5472 if (local.byte_buffer_in_use)
5474 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5475 local.total_bytes++;
5478 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5480 assemble_zeros (local.size - local.total_bytes);
5481 local.total_bytes = local.size;
5485 return local.total_bytes;
5488 /* Mark DECL as weak. */
5490 static void
5491 mark_weak (tree decl)
5493 if (DECL_WEAK (decl))
5494 return;
5496 struct symtab_node *n = symtab_node::get (decl);
5497 if (n && n->refuse_visibility_changes)
5498 error ("%+qD declared weak after being used", decl);
5499 DECL_WEAK (decl) = 1;
5501 if (DECL_RTL_SET_P (decl)
5502 && MEM_P (DECL_RTL (decl))
5503 && XEXP (DECL_RTL (decl), 0)
5504 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5505 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5508 /* Merge weak status between NEWDECL and OLDDECL. */
5510 void
5511 merge_weak (tree newdecl, tree olddecl)
5513 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5515 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5517 tree *pwd;
5518 /* We put the NEWDECL on the weak_decls list at some point
5519 and OLDDECL as well. Keep just OLDDECL on the list. */
5520 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5521 if (TREE_VALUE (*pwd) == newdecl)
5523 *pwd = TREE_CHAIN (*pwd);
5524 break;
5527 return;
5530 if (DECL_WEAK (newdecl))
5532 tree wd;
5534 /* NEWDECL is weak, but OLDDECL is not. */
5536 /* If we already output the OLDDECL, we're in trouble; we can't
5537 go back and make it weak. This should never happen in
5538 unit-at-a-time compilation. */
5539 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5541 /* If we've already generated rtl referencing OLDDECL, we may
5542 have done so in a way that will not function properly with
5543 a weak symbol. Again in unit-at-a-time this should be
5544 impossible. */
5545 gcc_assert (!TREE_USED (olddecl)
5546 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5548 /* PR 49899: You cannot convert a static function into a weak, public function. */
5549 if (! TREE_PUBLIC (olddecl) && TREE_PUBLIC (newdecl))
5550 error ("weak declaration of %q+D being applied to a already "
5551 "existing, static definition", newdecl);
5553 if (TARGET_SUPPORTS_WEAK)
5555 /* We put the NEWDECL on the weak_decls list at some point.
5556 Replace it with the OLDDECL. */
5557 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5558 if (TREE_VALUE (wd) == newdecl)
5560 TREE_VALUE (wd) = olddecl;
5561 break;
5563 /* We may not find the entry on the list. If NEWDECL is a
5564 weak alias, then we will have already called
5565 globalize_decl to remove the entry; in that case, we do
5566 not need to do anything. */
5569 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5570 mark_weak (olddecl);
5572 else
5573 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5574 weak. Just update NEWDECL to indicate that it's weak too. */
5575 mark_weak (newdecl);
5578 /* Declare DECL to be a weak symbol. */
5580 void
5581 declare_weak (tree decl)
5583 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5584 if (! TREE_PUBLIC (decl))
5586 error ("weak declaration of %q+D must be public", decl);
5587 return;
5589 else if (!TARGET_SUPPORTS_WEAK)
5590 warning (0, "weak declaration of %q+D not supported", decl);
5592 mark_weak (decl);
5593 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5594 DECL_ATTRIBUTES (decl)
5595 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5598 static void
5599 weak_finish_1 (tree decl)
5601 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5602 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5603 #endif
5605 if (! TREE_USED (decl))
5606 return;
5608 #ifdef ASM_WEAKEN_DECL
5609 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5610 #else
5611 #ifdef ASM_WEAKEN_LABEL
5612 ASM_WEAKEN_LABEL (asm_out_file, name);
5613 #else
5614 #ifdef ASM_OUTPUT_WEAK_ALIAS
5616 static bool warn_once = 0;
5617 if (! warn_once)
5619 warning (0, "only weak aliases are supported in this configuration");
5620 warn_once = 1;
5622 return;
5624 #endif
5625 #endif
5626 #endif
5629 /* Fiven an assembly name, find the decl it is associated with. */
5630 static tree
5631 find_decl (tree target)
5633 symtab_node *node = symtab_node::get_for_asmname (target);
5634 if (node)
5635 return node->decl;
5636 return NULL_TREE;
5639 /* This TREE_LIST contains weakref targets. */
5641 static GTY(()) tree weakref_targets;
5643 /* Emit any pending weak declarations. */
5645 void
5646 weak_finish (void)
5648 tree t;
5650 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5652 tree alias_decl = TREE_PURPOSE (t);
5653 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5655 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5656 /* Remove alias_decl from the weak list, but leave entries for
5657 the target alone. */
5658 target = NULL_TREE;
5659 #ifndef ASM_OUTPUT_WEAKREF
5660 else if (! TREE_SYMBOL_REFERENCED (target))
5662 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5663 defined, otherwise we and weak_finish_1 would use
5664 different macros. */
5665 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5666 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5667 # else
5668 tree decl = find_decl (target);
5670 if (! decl)
5672 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5673 TREE_CODE (alias_decl), target,
5674 TREE_TYPE (alias_decl));
5676 DECL_EXTERNAL (decl) = 1;
5677 TREE_PUBLIC (decl) = 1;
5678 DECL_ARTIFICIAL (decl) = 1;
5679 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5680 TREE_USED (decl) = 1;
5683 weak_finish_1 (decl);
5684 # endif
5686 #endif
5689 tree *p;
5690 tree t2;
5692 /* Remove the alias and the target from the pending weak list
5693 so that we do not emit any .weak directives for the former,
5694 nor multiple .weak directives for the latter. */
5695 for (p = &weak_decls; (t2 = *p) ; )
5697 if (TREE_VALUE (t2) == alias_decl
5698 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5699 *p = TREE_CHAIN (t2);
5700 else
5701 p = &TREE_CHAIN (t2);
5704 /* Remove other weakrefs to the same target, to speed things up. */
5705 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5707 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5708 *p = TREE_CHAIN (t2);
5709 else
5710 p = &TREE_CHAIN (t2);
5715 for (t = weak_decls; t; t = TREE_CHAIN (t))
5717 tree decl = TREE_VALUE (t);
5719 weak_finish_1 (decl);
5723 /* Emit the assembly bits to indicate that DECL is globally visible. */
5725 static void
5726 globalize_decl (tree decl)
5729 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5730 if (DECL_WEAK (decl))
5732 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5733 tree *p, t;
5735 #ifdef ASM_WEAKEN_DECL
5736 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5737 #else
5738 ASM_WEAKEN_LABEL (asm_out_file, name);
5739 #endif
5741 /* Remove this function from the pending weak list so that
5742 we do not emit multiple .weak directives for it. */
5743 for (p = &weak_decls; (t = *p) ; )
5745 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5746 *p = TREE_CHAIN (t);
5747 else
5748 p = &TREE_CHAIN (t);
5751 /* Remove weakrefs to the same target from the pending weakref
5752 list, for the same reason. */
5753 for (p = &weakref_targets; (t = *p) ; )
5755 if (DECL_ASSEMBLER_NAME (decl)
5756 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5757 *p = TREE_CHAIN (t);
5758 else
5759 p = &TREE_CHAIN (t);
5762 return;
5764 #endif
5766 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5769 vec<alias_pair, va_gc> *alias_pairs;
5771 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5772 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5773 tree node is DECL to have the value of the tree node TARGET. */
5775 void
5776 do_assemble_alias (tree decl, tree target)
5778 tree id;
5780 /* Emulated TLS had better not get this var. */
5781 gcc_assert (!(!targetm.have_tls
5782 && VAR_P (decl)
5783 && DECL_THREAD_LOCAL_P (decl)));
5785 if (TREE_ASM_WRITTEN (decl))
5786 return;
5788 id = DECL_ASSEMBLER_NAME (decl);
5789 ultimate_transparent_alias_target (&id);
5790 ultimate_transparent_alias_target (&target);
5792 /* We must force creation of DECL_RTL for debug info generation, even though
5793 we don't use it here. */
5794 make_decl_rtl (decl);
5796 TREE_ASM_WRITTEN (decl) = 1;
5797 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5798 TREE_ASM_WRITTEN (id) = 1;
5800 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5802 if (!TREE_SYMBOL_REFERENCED (target))
5803 weakref_targets = tree_cons (decl, target, weakref_targets);
5805 #ifdef ASM_OUTPUT_WEAKREF
5806 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5807 IDENTIFIER_POINTER (id),
5808 IDENTIFIER_POINTER (target));
5809 #else
5810 if (!TARGET_SUPPORTS_WEAK)
5812 error_at (DECL_SOURCE_LOCATION (decl),
5813 "weakref is not supported in this configuration");
5814 return;
5816 #endif
5817 return;
5820 #ifdef ASM_OUTPUT_DEF
5821 tree orig_decl = decl;
5823 if (TREE_CODE (decl) == FUNCTION_DECL
5824 && cgraph_node::get (decl)->instrumentation_clone
5825 && cgraph_node::get (decl)->instrumented_version)
5826 orig_decl = cgraph_node::get (decl)->instrumented_version->decl;
5828 /* Make name accessible from other files, if appropriate. */
5830 if (TREE_PUBLIC (decl) || TREE_PUBLIC (orig_decl))
5832 globalize_decl (decl);
5833 maybe_assemble_visibility (decl);
5835 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5837 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5838 if (targetm.has_ifunc_p ())
5839 ASM_OUTPUT_TYPE_DIRECTIVE
5840 (asm_out_file, IDENTIFIER_POINTER (id),
5841 IFUNC_ASM_TYPE);
5842 else
5843 #endif
5844 error_at (DECL_SOURCE_LOCATION (decl),
5845 "ifunc is not supported on this target");
5848 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5849 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5850 # else
5851 ASM_OUTPUT_DEF (asm_out_file,
5852 IDENTIFIER_POINTER (id),
5853 IDENTIFIER_POINTER (target));
5854 # endif
5855 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5857 const char *name;
5858 tree *p, t;
5860 name = IDENTIFIER_POINTER (id);
5861 # ifdef ASM_WEAKEN_DECL
5862 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5863 # else
5864 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5865 # endif
5866 /* Remove this function from the pending weak list so that
5867 we do not emit multiple .weak directives for it. */
5868 for (p = &weak_decls; (t = *p) ; )
5869 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t))
5870 || id == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5871 *p = TREE_CHAIN (t);
5872 else
5873 p = &TREE_CHAIN (t);
5875 /* Remove weakrefs to the same target from the pending weakref
5876 list, for the same reason. */
5877 for (p = &weakref_targets; (t = *p) ; )
5879 if (id == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5880 *p = TREE_CHAIN (t);
5881 else
5882 p = &TREE_CHAIN (t);
5885 #endif
5888 /* Emit an assembler directive to make the symbol for DECL an alias to
5889 the symbol for TARGET. */
5891 void
5892 assemble_alias (tree decl, tree target)
5894 tree target_decl;
5896 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5898 tree alias = DECL_ASSEMBLER_NAME (decl);
5900 ultimate_transparent_alias_target (&target);
5902 if (alias == target)
5903 error ("weakref %q+D ultimately targets itself", decl);
5904 if (TREE_PUBLIC (decl))
5905 error ("weakref %q+D must have static linkage", decl);
5907 else
5909 #if !defined (ASM_OUTPUT_DEF)
5910 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5911 error_at (DECL_SOURCE_LOCATION (decl),
5912 "alias definitions not supported in this configuration");
5913 TREE_ASM_WRITTEN (decl) = 1;
5914 return;
5915 # else
5916 if (!DECL_WEAK (decl))
5918 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5919 error_at (DECL_SOURCE_LOCATION (decl),
5920 "ifunc is not supported in this configuration");
5921 else
5922 error_at (DECL_SOURCE_LOCATION (decl),
5923 "only weak aliases are supported in this configuration");
5924 TREE_ASM_WRITTEN (decl) = 1;
5925 return;
5927 # endif
5928 #endif
5930 TREE_USED (decl) = 1;
5932 /* Allow aliases to aliases. */
5933 if (TREE_CODE (decl) == FUNCTION_DECL)
5934 cgraph_node::get_create (decl)->alias = true;
5935 else
5936 varpool_node::get_create (decl)->alias = true;
5938 /* If the target has already been emitted, we don't have to queue the
5939 alias. This saves a tad of memory. */
5940 if (symtab->global_info_ready)
5941 target_decl = find_decl (target);
5942 else
5943 target_decl= NULL;
5944 if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5945 || symtab->state >= EXPANSION)
5946 do_assemble_alias (decl, target);
5947 else
5949 alias_pair p = {decl, target};
5950 vec_safe_push (alias_pairs, p);
5954 /* Record and output a table of translations from original function
5955 to its transaction aware clone. Note that tm_pure functions are
5956 considered to be their own clone. */
5958 struct tm_clone_hasher : ggc_cache_ptr_hash<tree_map>
5960 static hashval_t hash (tree_map *m) { return tree_map_hash (m); }
5961 static bool equal (tree_map *a, tree_map *b) { return tree_map_eq (a, b); }
5963 static int
5964 keep_cache_entry (tree_map *&e)
5966 return ggc_marked_p (e->base.from);
5970 static GTY((cache)) hash_table<tm_clone_hasher> *tm_clone_hash;
5972 void
5973 record_tm_clone_pair (tree o, tree n)
5975 struct tree_map **slot, *h;
5977 if (tm_clone_hash == NULL)
5978 tm_clone_hash = hash_table<tm_clone_hasher>::create_ggc (32);
5980 h = ggc_alloc<tree_map> ();
5981 h->hash = htab_hash_pointer (o);
5982 h->base.from = o;
5983 h->to = n;
5985 slot = tm_clone_hash->find_slot_with_hash (h, h->hash, INSERT);
5986 *slot = h;
5989 tree
5990 get_tm_clone_pair (tree o)
5992 if (tm_clone_hash)
5994 struct tree_map *h, in;
5996 in.base.from = o;
5997 in.hash = htab_hash_pointer (o);
5998 h = tm_clone_hash->find_with_hash (&in, in.hash);
5999 if (h)
6000 return h->to;
6002 return NULL_TREE;
6005 struct tm_alias_pair
6007 unsigned int uid;
6008 tree from;
6009 tree to;
6013 /* Dump the actual pairs to the .tm_clone_table section. */
6015 static void
6016 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
6018 unsigned i;
6019 tm_alias_pair *p;
6020 bool switched = false;
6022 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
6024 tree src = p->from;
6025 tree dst = p->to;
6026 struct cgraph_node *src_n = cgraph_node::get (src);
6027 struct cgraph_node *dst_n = cgraph_node::get (dst);
6029 /* The function ipa_tm_create_version() marks the clone as needed if
6030 the original function was needed. But we also mark the clone as
6031 needed if we ever called the clone indirectly through
6032 TM_GETTMCLONE. If neither of these are true, we didn't generate
6033 a clone, and we didn't call it indirectly... no sense keeping it
6034 in the clone table. */
6035 if (!dst_n || !dst_n->definition)
6036 continue;
6038 /* This covers the case where we have optimized the original
6039 function away, and only access the transactional clone. */
6040 if (!src_n || !src_n->definition)
6041 continue;
6043 if (!switched)
6045 switch_to_section (targetm.asm_out.tm_clone_table_section ());
6046 assemble_align (POINTER_SIZE);
6047 switched = true;
6050 assemble_integer (XEXP (DECL_RTL (src), 0),
6051 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
6052 assemble_integer (XEXP (DECL_RTL (dst), 0),
6053 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
6057 /* Provide a default for the tm_clone_table section. */
6059 section *
6060 default_clone_table_section (void)
6062 return get_named_section (NULL, ".tm_clone_table", 3);
6065 /* Helper comparison function for qsorting by the DECL_UID stored in
6066 alias_pair->emitted_diags. */
6068 static int
6069 tm_alias_pair_cmp (const void *x, const void *y)
6071 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
6072 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
6073 if (p1->uid < p2->uid)
6074 return -1;
6075 if (p1->uid > p2->uid)
6076 return 1;
6077 return 0;
6080 void
6081 finish_tm_clone_pairs (void)
6083 vec<tm_alias_pair> tm_alias_pairs = vNULL;
6085 if (tm_clone_hash == NULL)
6086 return;
6088 /* We need a determenistic order for the .tm_clone_table, otherwise
6089 we will get bootstrap comparison failures, so dump the hash table
6090 to a vector, sort it, and dump the vector. */
6092 /* Dump the hashtable to a vector. */
6093 tree_map *map;
6094 hash_table<tm_clone_hasher>::iterator iter;
6095 FOR_EACH_HASH_TABLE_ELEMENT (*tm_clone_hash, map, tree_map *, iter)
6097 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
6098 tm_alias_pairs.safe_push (p);
6100 /* Sort it. */
6101 tm_alias_pairs.qsort (tm_alias_pair_cmp);
6103 /* Dump it. */
6104 dump_tm_clone_pairs (tm_alias_pairs);
6106 tm_clone_hash->empty ();
6107 tm_clone_hash = NULL;
6108 tm_alias_pairs.release ();
6112 /* Emit an assembler directive to set symbol for DECL visibility to
6113 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
6115 void
6116 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
6117 int vis ATTRIBUTE_UNUSED)
6119 #ifdef HAVE_GAS_HIDDEN
6120 static const char * const visibility_types[] = {
6121 NULL, "protected", "hidden", "internal"
6124 const char *name, *type;
6125 tree id;
6127 id = DECL_ASSEMBLER_NAME (decl);
6128 ultimate_transparent_alias_target (&id);
6129 name = IDENTIFIER_POINTER (id);
6131 type = visibility_types[vis];
6133 fprintf (asm_out_file, "\t.%s\t", type);
6134 assemble_name (asm_out_file, name);
6135 fprintf (asm_out_file, "\n");
6136 #else
6137 if (!DECL_ARTIFICIAL (decl))
6138 warning (OPT_Wattributes, "visibility attribute not supported "
6139 "in this configuration; ignored");
6140 #endif
6143 /* A helper function to call assemble_visibility when needed for a decl. */
6146 maybe_assemble_visibility (tree decl)
6148 enum symbol_visibility vis = DECL_VISIBILITY (decl);
6150 if (TREE_CODE (decl) == FUNCTION_DECL
6151 && cgraph_node::get (decl)
6152 && cgraph_node::get (decl)->instrumentation_clone
6153 && cgraph_node::get (decl)->instrumented_version)
6154 vis = DECL_VISIBILITY (cgraph_node::get (decl)->instrumented_version->decl);
6156 if (vis != VISIBILITY_DEFAULT)
6158 targetm.asm_out.assemble_visibility (decl, vis);
6159 return 1;
6161 else
6162 return 0;
6165 /* Returns 1 if the target configuration supports defining public symbols
6166 so that one of them will be chosen at link time instead of generating a
6167 multiply-defined symbol error, whether through the use of weak symbols or
6168 a target-specific mechanism for having duplicates discarded. */
6171 supports_one_only (void)
6173 if (SUPPORTS_ONE_ONLY)
6174 return 1;
6175 return TARGET_SUPPORTS_WEAK;
6178 /* Set up DECL as a public symbol that can be defined in multiple
6179 translation units without generating a linker error. */
6181 void
6182 make_decl_one_only (tree decl, tree comdat_group)
6184 struct symtab_node *symbol;
6185 gcc_assert (VAR_OR_FUNCTION_DECL_P (decl));
6187 TREE_PUBLIC (decl) = 1;
6189 if (VAR_P (decl))
6190 symbol = varpool_node::get_create (decl);
6191 else
6192 symbol = cgraph_node::get_create (decl);
6194 if (SUPPORTS_ONE_ONLY)
6196 #ifdef MAKE_DECL_ONE_ONLY
6197 MAKE_DECL_ONE_ONLY (decl);
6198 #endif
6199 symbol->set_comdat_group (comdat_group);
6201 else if (VAR_P (decl)
6202 && (DECL_INITIAL (decl) == 0
6203 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
6204 DECL_COMMON (decl) = 1;
6205 else
6207 gcc_assert (TARGET_SUPPORTS_WEAK);
6208 DECL_WEAK (decl) = 1;
6212 void
6213 init_varasm_once (void)
6215 section_htab = hash_table<section_hasher>::create_ggc (31);
6216 object_block_htab = hash_table<object_block_hasher>::create_ggc (31);
6217 const_desc_htab = hash_table<tree_descriptor_hasher>::create_ggc (1009);
6219 shared_constant_pool = create_constant_pool ();
6221 #ifdef TEXT_SECTION_ASM_OP
6222 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
6223 TEXT_SECTION_ASM_OP);
6224 #endif
6226 #ifdef DATA_SECTION_ASM_OP
6227 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
6228 DATA_SECTION_ASM_OP);
6229 #endif
6231 #ifdef SDATA_SECTION_ASM_OP
6232 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
6233 SDATA_SECTION_ASM_OP);
6234 #endif
6236 #ifdef READONLY_DATA_SECTION_ASM_OP
6237 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
6238 READONLY_DATA_SECTION_ASM_OP);
6239 #endif
6241 #ifdef CTORS_SECTION_ASM_OP
6242 ctors_section = get_unnamed_section (0, output_section_asm_op,
6243 CTORS_SECTION_ASM_OP);
6244 #endif
6246 #ifdef DTORS_SECTION_ASM_OP
6247 dtors_section = get_unnamed_section (0, output_section_asm_op,
6248 DTORS_SECTION_ASM_OP);
6249 #endif
6251 #ifdef BSS_SECTION_ASM_OP
6252 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6253 output_section_asm_op,
6254 BSS_SECTION_ASM_OP);
6255 #endif
6257 #ifdef SBSS_SECTION_ASM_OP
6258 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6259 output_section_asm_op,
6260 SBSS_SECTION_ASM_OP);
6261 #endif
6263 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6264 | SECTION_COMMON, emit_tls_common);
6265 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6266 | SECTION_COMMON, emit_local);
6267 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6268 | SECTION_COMMON, emit_common);
6270 #if defined ASM_OUTPUT_ALIGNED_BSS
6271 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
6272 emit_bss);
6273 #endif
6275 targetm.asm_out.init_sections ();
6277 if (readonly_data_section == NULL)
6278 readonly_data_section = text_section;
6280 #ifdef ASM_OUTPUT_EXTERNAL
6281 pending_assemble_externals_set = new hash_set<tree>;
6282 #endif
6285 enum tls_model
6286 decl_default_tls_model (const_tree decl)
6288 enum tls_model kind;
6289 bool is_local;
6291 is_local = targetm.binds_local_p (decl);
6292 if (!flag_shlib)
6294 if (is_local)
6295 kind = TLS_MODEL_LOCAL_EXEC;
6296 else
6297 kind = TLS_MODEL_INITIAL_EXEC;
6300 /* Local dynamic is inefficient when we're not combining the
6301 parts of the address. */
6302 else if (optimize && is_local)
6303 kind = TLS_MODEL_LOCAL_DYNAMIC;
6304 else
6305 kind = TLS_MODEL_GLOBAL_DYNAMIC;
6306 if (kind < flag_tls_default)
6307 kind = flag_tls_default;
6309 return kind;
6312 /* Select a set of attributes for section NAME based on the properties
6313 of DECL and whether or not RELOC indicates that DECL's initializer
6314 might contain runtime relocations.
6316 We make the section read-only and executable for a function decl,
6317 read-only for a const data decl, and writable for a non-const data decl. */
6319 unsigned int
6320 default_section_type_flags (tree decl, const char *name, int reloc)
6322 unsigned int flags;
6324 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6325 flags = SECTION_CODE;
6326 else if (decl)
6328 enum section_category category
6329 = categorize_decl_for_section (decl, reloc);
6330 if (decl_readonly_section_1 (category))
6331 flags = 0;
6332 else if (category == SECCAT_DATA_REL_RO
6333 || category == SECCAT_DATA_REL_RO_LOCAL)
6334 flags = SECTION_WRITE | SECTION_RELRO;
6335 else
6336 flags = SECTION_WRITE;
6338 else
6340 flags = SECTION_WRITE;
6341 if (strcmp (name, ".data.rel.ro") == 0
6342 || strcmp (name, ".data.rel.ro.local") == 0)
6343 flags |= SECTION_RELRO;
6346 if (decl && DECL_P (decl) && DECL_COMDAT_GROUP (decl))
6347 flags |= SECTION_LINKONCE;
6349 if (strcmp (name, ".vtable_map_vars") == 0)
6350 flags |= SECTION_LINKONCE;
6352 if (decl && VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6353 flags |= SECTION_TLS | SECTION_WRITE;
6355 if (strcmp (name, ".bss") == 0
6356 || strncmp (name, ".bss.", 5) == 0
6357 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6358 || strcmp (name, ".persistent.bss") == 0
6359 || strcmp (name, ".sbss") == 0
6360 || strncmp (name, ".sbss.", 6) == 0
6361 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6362 flags |= SECTION_BSS;
6364 if (strcmp (name, ".tdata") == 0
6365 || strncmp (name, ".tdata.", 7) == 0
6366 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6367 flags |= SECTION_TLS;
6369 if (strcmp (name, ".tbss") == 0
6370 || strncmp (name, ".tbss.", 6) == 0
6371 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6372 flags |= SECTION_TLS | SECTION_BSS;
6374 /* Various sections have special ELF types that the assembler will
6375 assign by default based on the name. They are neither SHT_PROGBITS
6376 nor SHT_NOBITS, so when changing sections we don't want to print a
6377 section type (@progbits or @nobits). Rather than duplicating the
6378 assembler's knowledge of what those special name patterns are, just
6379 let the assembler choose the type if we don't know a specific
6380 reason to set it to something other than the default. SHT_PROGBITS
6381 is the default for sections whose name is not specially known to
6382 the assembler, so it does no harm to leave the choice to the
6383 assembler when @progbits is the best thing we know to use. If
6384 someone is silly enough to emit code or TLS variables to one of
6385 these sections, then don't handle them specially.
6387 default_elf_asm_named_section (below) handles the BSS, TLS, ENTSIZE, and
6388 LINKONCE cases when NOTYPE is not set, so leave those to its logic. */
6389 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS | SECTION_ENTSIZE))
6390 && !(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE)))
6391 flags |= SECTION_NOTYPE;
6393 return flags;
6396 /* Return true if the target supports some form of global BSS,
6397 either through bss_noswitch_section, or by selecting a BSS
6398 section in TARGET_ASM_SELECT_SECTION. */
6400 bool
6401 have_global_bss_p (void)
6403 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6406 /* Output assembly to switch to section NAME with attribute FLAGS.
6407 Four variants for common object file formats. */
6409 void
6410 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6411 unsigned int flags ATTRIBUTE_UNUSED,
6412 tree decl ATTRIBUTE_UNUSED)
6414 /* Some object formats don't support named sections at all. The
6415 front-end should already have flagged this as an error. */
6416 gcc_unreachable ();
6419 #ifndef TLS_SECTION_ASM_FLAG
6420 #define TLS_SECTION_ASM_FLAG 'T'
6421 #endif
6423 void
6424 default_elf_asm_named_section (const char *name, unsigned int flags,
6425 tree decl)
6427 char flagchars[11], *f = flagchars;
6428 unsigned int numeric_value = 0;
6430 /* If we have already declared this section, we can use an
6431 abbreviated form to switch back to it -- unless this section is
6432 part of a COMDAT groups, in which case GAS requires the full
6433 declaration every time. */
6434 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6435 && (flags & SECTION_DECLARED))
6437 fprintf (asm_out_file, "\t.section\t%s\n", name);
6438 return;
6441 /* If we have a machine specific flag, then use the numeric value to pass
6442 this on to GAS. */
6443 if (targetm.asm_out.elf_flags_numeric (flags, &numeric_value))
6444 snprintf (f, sizeof (flagchars), "0x%08x", numeric_value);
6445 else
6447 if (!(flags & SECTION_DEBUG))
6448 *f++ = 'a';
6449 #if defined (HAVE_GAS_SECTION_EXCLUDE) && HAVE_GAS_SECTION_EXCLUDE == 1
6450 if (flags & SECTION_EXCLUDE)
6451 *f++ = 'e';
6452 #endif
6453 if (flags & SECTION_WRITE)
6454 *f++ = 'w';
6455 if (flags & SECTION_CODE)
6456 *f++ = 'x';
6457 if (flags & SECTION_SMALL)
6458 *f++ = 's';
6459 if (flags & SECTION_MERGE)
6460 *f++ = 'M';
6461 if (flags & SECTION_STRINGS)
6462 *f++ = 'S';
6463 if (flags & SECTION_TLS)
6464 *f++ = TLS_SECTION_ASM_FLAG;
6465 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6466 *f++ = 'G';
6467 #ifdef MACH_DEP_SECTION_ASM_FLAG
6468 if (flags & SECTION_MACH_DEP)
6469 *f++ = MACH_DEP_SECTION_ASM_FLAG;
6470 #endif
6471 *f = '\0';
6474 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6476 /* default_section_type_flags (above) knows which flags need special
6477 handling here, and sets NOTYPE when none of these apply so that the
6478 assembler's logic for default types can apply to user-chosen
6479 section names. */
6480 if (!(flags & SECTION_NOTYPE))
6482 const char *type;
6483 const char *format;
6485 if (flags & SECTION_BSS)
6486 type = "nobits";
6487 else
6488 type = "progbits";
6490 format = ",@%s";
6491 /* On platforms that use "@" as the assembly comment character,
6492 use "%" instead. */
6493 if (strcmp (ASM_COMMENT_START, "@") == 0)
6494 format = ",%%%s";
6495 fprintf (asm_out_file, format, type);
6497 if (flags & SECTION_ENTSIZE)
6498 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6499 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6501 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6502 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6503 else
6504 fprintf (asm_out_file, ",%s,comdat",
6505 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6509 putc ('\n', asm_out_file);
6512 void
6513 default_coff_asm_named_section (const char *name, unsigned int flags,
6514 tree decl ATTRIBUTE_UNUSED)
6516 char flagchars[8], *f = flagchars;
6518 if (flags & SECTION_WRITE)
6519 *f++ = 'w';
6520 if (flags & SECTION_CODE)
6521 *f++ = 'x';
6522 *f = '\0';
6524 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6527 void
6528 default_pe_asm_named_section (const char *name, unsigned int flags,
6529 tree decl)
6531 default_coff_asm_named_section (name, flags, decl);
6533 if (flags & SECTION_LINKONCE)
6535 /* Functions may have been compiled at various levels of
6536 optimization so we can't use `same_size' here.
6537 Instead, have the linker pick one. */
6538 fprintf (asm_out_file, "\t.linkonce %s\n",
6539 (flags & SECTION_CODE ? "discard" : "same_size"));
6543 /* The lame default section selector. */
6545 section *
6546 default_select_section (tree decl, int reloc,
6547 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6549 if (DECL_P (decl))
6551 if (decl_readonly_section (decl, reloc))
6552 return readonly_data_section;
6554 else if (TREE_CODE (decl) == CONSTRUCTOR)
6556 if (! ((flag_pic && reloc)
6557 || !TREE_READONLY (decl)
6558 || TREE_SIDE_EFFECTS (decl)
6559 || !TREE_CONSTANT (decl)))
6560 return readonly_data_section;
6562 else if (TREE_CODE (decl) == STRING_CST)
6563 return readonly_data_section;
6564 else if (! (flag_pic && reloc))
6565 return readonly_data_section;
6567 return data_section;
6570 enum section_category
6571 categorize_decl_for_section (const_tree decl, int reloc)
6573 enum section_category ret;
6575 if (TREE_CODE (decl) == FUNCTION_DECL)
6576 return SECCAT_TEXT;
6577 else if (TREE_CODE (decl) == STRING_CST)
6579 if ((flag_sanitize & SANITIZE_ADDRESS)
6580 && asan_protect_global (CONST_CAST_TREE (decl)))
6581 /* or !flag_merge_constants */
6582 return SECCAT_RODATA;
6583 else
6584 return SECCAT_RODATA_MERGE_STR;
6586 else if (VAR_P (decl))
6588 tree d = CONST_CAST_TREE (decl);
6589 if (bss_initializer_p (decl))
6590 ret = SECCAT_BSS;
6591 else if (! TREE_READONLY (decl)
6592 || TREE_SIDE_EFFECTS (decl)
6593 || (DECL_INITIAL (decl)
6594 && ! TREE_CONSTANT (DECL_INITIAL (decl))))
6596 /* Here the reloc_rw_mask is not testing whether the section should
6597 be read-only or not, but whether the dynamic link will have to
6598 do something. If so, we wish to segregate the data in order to
6599 minimize cache misses inside the dynamic linker. */
6600 if (reloc & targetm.asm_out.reloc_rw_mask ())
6601 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6602 else
6603 ret = SECCAT_DATA;
6605 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6606 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6607 else if (reloc || flag_merge_constants < 2
6608 || ((flag_sanitize & SANITIZE_ADDRESS)
6609 /* PR 81697: for architectures that use section anchors we
6610 need to ignore DECL_RTL_SET_P (decl) for string constants
6611 inside this asan_protect_global call because otherwise
6612 we'll wrongly put them into SECCAT_RODATA_MERGE_CONST
6613 section, set DECL_RTL (decl) later on and add DECL to
6614 protected globals via successive asan_protect_global
6615 calls. In this scenario we'll end up with wrong
6616 alignment of these strings at runtime and possible ASan
6617 false positives. */
6618 && asan_protect_global (d, use_object_blocks_p ()
6619 && use_blocks_for_decl_p (d))))
6620 /* C and C++ don't allow different variables to share the same
6621 location. -fmerge-all-constants allows even that (at the
6622 expense of not conforming). */
6623 ret = SECCAT_RODATA;
6624 else if (DECL_INITIAL (decl)
6625 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6626 ret = SECCAT_RODATA_MERGE_STR_INIT;
6627 else
6628 ret = SECCAT_RODATA_MERGE_CONST;
6630 else if (TREE_CODE (decl) == CONSTRUCTOR)
6632 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6633 || TREE_SIDE_EFFECTS (decl)
6634 || ! TREE_CONSTANT (decl))
6635 ret = SECCAT_DATA;
6636 else
6637 ret = SECCAT_RODATA;
6639 else
6640 ret = SECCAT_RODATA;
6642 /* There are no read-only thread-local sections. */
6643 if (VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6645 /* Note that this would be *just* SECCAT_BSS, except that there's
6646 no concept of a read-only thread-local-data section. */
6647 if (ret == SECCAT_BSS
6648 || DECL_INITIAL (decl) == NULL
6649 || (flag_zero_initialized_in_bss
6650 && initializer_zerop (DECL_INITIAL (decl))))
6651 ret = SECCAT_TBSS;
6652 else
6653 ret = SECCAT_TDATA;
6656 /* If the target uses small data sections, select it. */
6657 else if (targetm.in_small_data_p (decl))
6659 if (ret == SECCAT_BSS)
6660 ret = SECCAT_SBSS;
6661 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6662 ret = SECCAT_SRODATA;
6663 else
6664 ret = SECCAT_SDATA;
6667 return ret;
6670 static bool
6671 decl_readonly_section_1 (enum section_category category)
6673 switch (category)
6675 case SECCAT_RODATA:
6676 case SECCAT_RODATA_MERGE_STR:
6677 case SECCAT_RODATA_MERGE_STR_INIT:
6678 case SECCAT_RODATA_MERGE_CONST:
6679 case SECCAT_SRODATA:
6680 return true;
6681 default:
6682 return false;
6686 bool
6687 decl_readonly_section (const_tree decl, int reloc)
6689 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6692 /* Select a section based on the above categorization. */
6694 section *
6695 default_elf_select_section (tree decl, int reloc,
6696 unsigned HOST_WIDE_INT align)
6698 const char *sname;
6699 switch (categorize_decl_for_section (decl, reloc))
6701 case SECCAT_TEXT:
6702 /* We're not supposed to be called on FUNCTION_DECLs. */
6703 gcc_unreachable ();
6704 case SECCAT_RODATA:
6705 return readonly_data_section;
6706 case SECCAT_RODATA_MERGE_STR:
6707 return mergeable_string_section (decl, align, 0);
6708 case SECCAT_RODATA_MERGE_STR_INIT:
6709 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6710 case SECCAT_RODATA_MERGE_CONST:
6711 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6712 case SECCAT_SRODATA:
6713 sname = ".sdata2";
6714 break;
6715 case SECCAT_DATA:
6716 return data_section;
6717 case SECCAT_DATA_REL:
6718 sname = ".data.rel";
6719 break;
6720 case SECCAT_DATA_REL_LOCAL:
6721 sname = ".data.rel.local";
6722 break;
6723 case SECCAT_DATA_REL_RO:
6724 sname = ".data.rel.ro";
6725 break;
6726 case SECCAT_DATA_REL_RO_LOCAL:
6727 sname = ".data.rel.ro.local";
6728 break;
6729 case SECCAT_SDATA:
6730 sname = ".sdata";
6731 break;
6732 case SECCAT_TDATA:
6733 sname = ".tdata";
6734 break;
6735 case SECCAT_BSS:
6736 if (bss_section)
6737 return bss_section;
6738 sname = ".bss";
6739 break;
6740 case SECCAT_SBSS:
6741 sname = ".sbss";
6742 break;
6743 case SECCAT_TBSS:
6744 sname = ".tbss";
6745 break;
6746 default:
6747 gcc_unreachable ();
6750 return get_named_section (decl, sname, reloc);
6753 /* Construct a unique section name based on the decl name and the
6754 categorization performed above. */
6756 void
6757 default_unique_section (tree decl, int reloc)
6759 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6760 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6761 const char *prefix, *name, *linkonce;
6762 char *string;
6763 tree id;
6765 switch (categorize_decl_for_section (decl, reloc))
6767 case SECCAT_TEXT:
6768 prefix = one_only ? ".t" : ".text";
6769 break;
6770 case SECCAT_RODATA:
6771 case SECCAT_RODATA_MERGE_STR:
6772 case SECCAT_RODATA_MERGE_STR_INIT:
6773 case SECCAT_RODATA_MERGE_CONST:
6774 prefix = one_only ? ".r" : ".rodata";
6775 break;
6776 case SECCAT_SRODATA:
6777 prefix = one_only ? ".s2" : ".sdata2";
6778 break;
6779 case SECCAT_DATA:
6780 prefix = one_only ? ".d" : ".data";
6781 break;
6782 case SECCAT_DATA_REL:
6783 prefix = one_only ? ".d.rel" : ".data.rel";
6784 break;
6785 case SECCAT_DATA_REL_LOCAL:
6786 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6787 break;
6788 case SECCAT_DATA_REL_RO:
6789 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6790 break;
6791 case SECCAT_DATA_REL_RO_LOCAL:
6792 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6793 break;
6794 case SECCAT_SDATA:
6795 prefix = one_only ? ".s" : ".sdata";
6796 break;
6797 case SECCAT_BSS:
6798 prefix = one_only ? ".b" : ".bss";
6799 break;
6800 case SECCAT_SBSS:
6801 prefix = one_only ? ".sb" : ".sbss";
6802 break;
6803 case SECCAT_TDATA:
6804 prefix = one_only ? ".td" : ".tdata";
6805 break;
6806 case SECCAT_TBSS:
6807 prefix = one_only ? ".tb" : ".tbss";
6808 break;
6809 default:
6810 gcc_unreachable ();
6813 id = DECL_ASSEMBLER_NAME (decl);
6814 ultimate_transparent_alias_target (&id);
6815 name = IDENTIFIER_POINTER (id);
6816 name = targetm.strip_name_encoding (name);
6818 /* If we're using one_only, then there needs to be a .gnu.linkonce
6819 prefix to the section name. */
6820 linkonce = one_only ? ".gnu.linkonce" : "";
6822 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6824 set_decl_section_name (decl, string);
6827 /* Subroutine of compute_reloc_for_rtx for leaf rtxes. */
6829 static int
6830 compute_reloc_for_rtx_1 (const_rtx x)
6832 switch (GET_CODE (x))
6834 case SYMBOL_REF:
6835 return SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6836 case LABEL_REF:
6837 return 1;
6838 default:
6839 return 0;
6843 /* Like compute_reloc_for_constant, except for an RTX. The return value
6844 is a mask for which bit 1 indicates a global relocation, and bit 0
6845 indicates a local relocation. */
6847 static int
6848 compute_reloc_for_rtx (const_rtx x)
6850 switch (GET_CODE (x))
6852 case SYMBOL_REF:
6853 case LABEL_REF:
6854 return compute_reloc_for_rtx_1 (x);
6856 case CONST:
6858 int reloc = 0;
6859 subrtx_iterator::array_type array;
6860 FOR_EACH_SUBRTX (iter, array, x, ALL)
6861 reloc |= compute_reloc_for_rtx_1 (*iter);
6862 return reloc;
6865 default:
6866 return 0;
6870 section *
6871 default_select_rtx_section (machine_mode mode ATTRIBUTE_UNUSED,
6872 rtx x,
6873 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6875 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6876 return data_section;
6877 else
6878 return readonly_data_section;
6881 section *
6882 default_elf_select_rtx_section (machine_mode mode, rtx x,
6883 unsigned HOST_WIDE_INT align)
6885 int reloc = compute_reloc_for_rtx (x);
6887 /* ??? Handle small data here somehow. */
6889 if (reloc & targetm.asm_out.reloc_rw_mask ())
6891 if (reloc == 1)
6892 return get_named_section (NULL, ".data.rel.ro.local", 1);
6893 else
6894 return get_named_section (NULL, ".data.rel.ro", 3);
6897 return mergeable_constant_section (mode, align, 0);
6900 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6902 void
6903 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6905 rtx symbol;
6906 int flags;
6908 /* Careful not to prod global register variables. */
6909 if (!MEM_P (rtl))
6910 return;
6911 symbol = XEXP (rtl, 0);
6912 if (GET_CODE (symbol) != SYMBOL_REF)
6913 return;
6915 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6916 if (TREE_CODE (decl) == FUNCTION_DECL)
6917 flags |= SYMBOL_FLAG_FUNCTION;
6918 if (targetm.binds_local_p (decl))
6919 flags |= SYMBOL_FLAG_LOCAL;
6920 if (VAR_P (decl) && DECL_THREAD_LOCAL_P (decl))
6921 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6922 else if (targetm.in_small_data_p (decl))
6923 flags |= SYMBOL_FLAG_SMALL;
6924 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6925 being PUBLIC, the thing *must* be defined in this translation unit.
6926 Prevent this buglet from being propagated into rtl code as well. */
6927 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6928 flags |= SYMBOL_FLAG_EXTERNAL;
6930 SYMBOL_REF_FLAGS (symbol) = flags;
6933 /* By default, we do nothing for encode_section_info, so we need not
6934 do anything but discard the '*' marker. */
6936 const char *
6937 default_strip_name_encoding (const char *str)
6939 return str + (*str == '*');
6942 #ifdef ASM_OUTPUT_DEF
6943 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6944 anchor relative to ".", the current section position. */
6946 void
6947 default_asm_output_anchor (rtx symbol)
6949 char buffer[100];
6951 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6952 SYMBOL_REF_BLOCK_OFFSET (symbol));
6953 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6955 #endif
6957 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6959 bool
6960 default_use_anchors_for_symbol_p (const_rtx symbol)
6962 section *sect;
6963 tree decl;
6965 /* Don't use anchors for mergeable sections. The linker might move
6966 the objects around. */
6967 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6968 if (sect->common.flags & SECTION_MERGE)
6969 return false;
6971 /* Don't use anchors for small data sections. The small data register
6972 acts as an anchor for such sections. */
6973 if (sect->common.flags & SECTION_SMALL)
6974 return false;
6976 decl = SYMBOL_REF_DECL (symbol);
6977 if (decl && DECL_P (decl))
6979 /* Don't use section anchors for decls that might be defined or
6980 usurped by other modules. */
6981 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6982 return false;
6984 /* Don't use section anchors for decls that will be placed in a
6985 small data section. */
6986 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6987 one above. The problem is that we only use SECTION_SMALL for
6988 sections that should be marked as small in the section directive. */
6989 if (targetm.in_small_data_p (decl))
6990 return false;
6992 /* Don't use section anchors for decls that won't fit inside a single
6993 anchor range to reduce the amount of instructions required to refer
6994 to the entire declaration. */
6995 if (DECL_SIZE_UNIT (decl) == NULL_TREE
6996 || !tree_fits_uhwi_p (DECL_SIZE_UNIT (decl))
6997 || (tree_to_uhwi (DECL_SIZE_UNIT (decl))
6998 >= (unsigned HOST_WIDE_INT) targetm.max_anchor_offset))
6999 return false;
7002 return true;
7005 /* Return true when RESOLUTION indicate that symbol will be bound to the
7006 definition provided by current .o file. */
7008 static bool
7009 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
7011 return (resolution == LDPR_PREVAILING_DEF
7012 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
7013 || resolution == LDPR_PREVAILING_DEF_IRONLY);
7016 /* Return true when RESOLUTION indicate that symbol will be bound locally
7017 within current executable or DSO. */
7019 static bool
7020 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
7022 return (resolution == LDPR_PREVAILING_DEF
7023 || resolution == LDPR_PREVAILING_DEF_IRONLY
7024 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
7025 || resolution == LDPR_PREEMPTED_REG
7026 || resolution == LDPR_PREEMPTED_IR
7027 || resolution == LDPR_RESOLVED_IR
7028 || resolution == LDPR_RESOLVED_EXEC);
7031 /* COMMON_LOCAL_P is true means that the linker can guarantee that an
7032 uninitialized common symbol in the executable will still be defined
7033 (through COPY relocation) in the executable. */
7035 bool
7036 default_binds_local_p_3 (const_tree exp, bool shlib, bool weak_dominate,
7037 bool extern_protected_data, bool common_local_p)
7039 /* A non-decl is an entry in the constant pool. */
7040 if (!DECL_P (exp))
7041 return true;
7043 /* Weakrefs may not bind locally, even though the weakref itself is always
7044 static and therefore local. Similarly, the resolver for ifunc functions
7045 might resolve to a non-local function.
7046 FIXME: We can resolve the weakref case more curefuly by looking at the
7047 weakref alias. */
7048 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
7049 || (TREE_CODE (exp) == FUNCTION_DECL
7050 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
7051 return false;
7053 /* Static variables are always local. */
7054 if (! TREE_PUBLIC (exp))
7055 return true;
7057 /* With resolution file in hand, take look into resolutions.
7058 We can't just return true for resolved_locally symbols,
7059 because dynamic linking might overwrite symbols
7060 in shared libraries. */
7061 bool resolved_locally = false;
7063 bool uninited_common = (DECL_COMMON (exp)
7064 && (DECL_INITIAL (exp) == NULL
7065 || (!in_lto_p
7066 && DECL_INITIAL (exp) == error_mark_node)));
7068 /* A non-external variable is defined locally only if it isn't
7069 uninitialized COMMON variable or common_local_p is true. */
7070 bool defined_locally = (!DECL_EXTERNAL (exp)
7071 && (!uninited_common || common_local_p));
7072 if (symtab_node *node = symtab_node::get (exp))
7074 if (node->in_other_partition)
7075 defined_locally = true;
7076 if (node->can_be_discarded_p ())
7078 else if (resolution_to_local_definition_p (node->resolution))
7079 defined_locally = resolved_locally = true;
7080 else if (resolution_local_p (node->resolution))
7081 resolved_locally = true;
7083 if (defined_locally && weak_dominate && !shlib)
7084 resolved_locally = true;
7086 /* Undefined weak symbols are never defined locally. */
7087 if (DECL_WEAK (exp) && !defined_locally)
7088 return false;
7090 /* A symbol is local if the user has said explicitly that it will be,
7091 or if we have a definition for the symbol. We cannot infer visibility
7092 for undefined symbols. */
7093 if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT
7094 && (TREE_CODE (exp) == FUNCTION_DECL
7095 || !extern_protected_data
7096 || DECL_VISIBILITY (exp) != VISIBILITY_PROTECTED)
7097 && (DECL_VISIBILITY_SPECIFIED (exp) || defined_locally))
7098 return true;
7100 /* If PIC, then assume that any global name can be overridden by
7101 symbols resolved from other modules. */
7102 if (shlib)
7103 return false;
7105 /* Variables defined outside this object might not be local. */
7106 if (DECL_EXTERNAL (exp) && !resolved_locally)
7107 return false;
7109 /* Non-dominant weak symbols are not defined locally. */
7110 if (DECL_WEAK (exp) && !resolved_locally)
7111 return false;
7113 /* Uninitialized COMMON variable may be unified with symbols
7114 resolved from other modules. */
7115 if (uninited_common && !resolved_locally)
7116 return false;
7118 /* Otherwise we're left with initialized (or non-common) global data
7119 which is of necessity defined locally. */
7120 return true;
7123 /* Assume ELF-ish defaults, since that's pretty much the most liberal
7124 wrt cross-module name binding. */
7126 bool
7127 default_binds_local_p (const_tree exp)
7129 return default_binds_local_p_3 (exp, flag_shlib != 0, true, false, false);
7132 /* Similar to default_binds_local_p, but common symbol may be local and
7133 extern protected data is non-local. */
7135 bool
7136 default_binds_local_p_2 (const_tree exp)
7138 return default_binds_local_p_3 (exp, flag_shlib != 0, true, true,
7139 !flag_pic);
7142 bool
7143 default_binds_local_p_1 (const_tree exp, int shlib)
7145 return default_binds_local_p_3 (exp, shlib != 0, false, false, false);
7148 /* Return true when references to DECL must bind to current definition in
7149 final executable.
7151 The condition is usually equivalent to whether the function binds to the
7152 current module (shared library or executable), that is to binds_local_p.
7153 We use this fact to avoid need for another target hook and implement
7154 the logic using binds_local_p and just special cases where
7155 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
7156 the weak definitions (that can be overwritten at linktime by other
7157 definition from different object file) and when resolution info is available
7158 we simply use the knowledge passed to us by linker plugin. */
7159 bool
7160 decl_binds_to_current_def_p (const_tree decl)
7162 gcc_assert (DECL_P (decl));
7163 if (!targetm.binds_local_p (decl))
7164 return false;
7165 if (!TREE_PUBLIC (decl))
7166 return true;
7168 /* When resolution is available, just use it. */
7169 if (symtab_node *node = symtab_node::get (decl))
7171 if (node->resolution != LDPR_UNKNOWN
7172 && !node->can_be_discarded_p ())
7173 return resolution_to_local_definition_p (node->resolution);
7176 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
7177 binds locally but still can be overwritten), DECL_COMMON (can be merged
7178 with a non-common definition somewhere in the same module) or
7179 DECL_EXTERNAL.
7180 This rely on fact that binds_local_p behave as decl_replaceable_p
7181 for all other declaration types. */
7182 if (DECL_WEAK (decl))
7183 return false;
7184 if (DECL_COMMON (decl)
7185 && (DECL_INITIAL (decl) == NULL
7186 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
7187 return false;
7188 if (DECL_EXTERNAL (decl))
7189 return false;
7190 return true;
7193 /* A replaceable function or variable is one which may be replaced
7194 at link-time with an entirely different definition, provided that the
7195 replacement has the same type. For example, functions declared
7196 with __attribute__((weak)) on most systems are replaceable.
7198 COMDAT functions are not replaceable, since all definitions of the
7199 function must be equivalent. It is important that COMDAT functions
7200 not be treated as replaceable so that use of C++ template
7201 instantiations is not penalized. */
7203 bool
7204 decl_replaceable_p (tree decl)
7206 gcc_assert (DECL_P (decl));
7207 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
7208 return false;
7209 if (!flag_semantic_interposition
7210 && !DECL_WEAK (decl))
7211 return false;
7212 return !decl_binds_to_current_def_p (decl);
7215 /* Default function to output code that will globalize a label. A
7216 target must define GLOBAL_ASM_OP or provide its own function to
7217 globalize a label. */
7218 #ifdef GLOBAL_ASM_OP
7219 void
7220 default_globalize_label (FILE * stream, const char *name)
7222 fputs (GLOBAL_ASM_OP, stream);
7223 assemble_name (stream, name);
7224 putc ('\n', stream);
7226 #endif /* GLOBAL_ASM_OP */
7228 /* Default function to output code that will globalize a declaration. */
7229 void
7230 default_globalize_decl_name (FILE * stream, tree decl)
7232 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
7233 targetm.asm_out.globalize_label (stream, name);
7236 /* Default function to output a label for unwind information. The
7237 default is to do nothing. A target that needs nonlocal labels for
7238 unwind information must provide its own function to do this. */
7239 void
7240 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
7241 tree decl ATTRIBUTE_UNUSED,
7242 int for_eh ATTRIBUTE_UNUSED,
7243 int empty ATTRIBUTE_UNUSED)
7247 /* Default function to output a label to divide up the exception table.
7248 The default is to do nothing. A target that needs/wants to divide
7249 up the table must provide it's own function to do this. */
7250 void
7251 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
7255 /* This is how to output an internal numbered label where PREFIX is
7256 the class of label and LABELNO is the number within the class. */
7258 void
7259 default_generate_internal_label (char *buf, const char *prefix,
7260 unsigned long labelno)
7262 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
7265 /* This is how to output an internal numbered label where PREFIX is
7266 the class of label and LABELNO is the number within the class. */
7268 void
7269 default_internal_label (FILE *stream, const char *prefix,
7270 unsigned long labelno)
7272 char *const buf = (char *) alloca (40 + strlen (prefix));
7273 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
7274 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
7278 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
7280 void
7281 default_asm_declare_constant_name (FILE *file, const char *name,
7282 const_tree exp ATTRIBUTE_UNUSED,
7283 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
7285 assemble_label (file, name);
7288 /* This is the default behavior at the beginning of a file. It's
7289 controlled by two other target-hook toggles. */
7290 void
7291 default_file_start (void)
7293 if (targetm.asm_file_start_app_off
7294 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
7295 fputs (ASM_APP_OFF, asm_out_file);
7297 if (targetm.asm_file_start_file_directive)
7299 /* LTO produced units have no meaningful main_input_filename. */
7300 if (in_lto_p)
7301 output_file_directive (asm_out_file, "<artificial>");
7302 else
7303 output_file_directive (asm_out_file, main_input_filename);
7307 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
7308 which emits a special section directive used to indicate whether or
7309 not this object file needs an executable stack. This is primarily
7310 a GNU extension to ELF but could be used on other targets. */
7312 int trampolines_created;
7314 void
7315 file_end_indicate_exec_stack (void)
7317 unsigned int flags = SECTION_DEBUG;
7318 if (trampolines_created)
7319 flags |= SECTION_CODE;
7321 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
7324 /* Emit a special section directive to indicate that this object file
7325 was compiled with -fsplit-stack. This is used to let the linker
7326 detect calls between split-stack code and non-split-stack code, so
7327 that it can modify the split-stack code to allocate a sufficiently
7328 large stack. We emit another special section if there are any
7329 functions in this file which have the no_split_stack attribute, to
7330 prevent the linker from warning about being unable to convert the
7331 functions if they call non-split-stack code. */
7333 void
7334 file_end_indicate_split_stack (void)
7336 if (flag_split_stack)
7338 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
7339 NULL));
7340 if (saw_no_split_stack)
7341 switch_to_section (get_section (".note.GNU-no-split-stack",
7342 SECTION_DEBUG, NULL));
7346 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
7347 a get_unnamed_section callback. */
7349 void
7350 output_section_asm_op (const void *directive)
7352 fprintf (asm_out_file, "%s\n", (const char *) directive);
7355 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
7356 the current section is NEW_SECTION. */
7358 void
7359 switch_to_section (section *new_section)
7361 if (in_section == new_section)
7362 return;
7364 if (new_section->common.flags & SECTION_FORGET)
7365 in_section = NULL;
7366 else
7367 in_section = new_section;
7369 switch (SECTION_STYLE (new_section))
7371 case SECTION_NAMED:
7372 targetm.asm_out.named_section (new_section->named.name,
7373 new_section->named.common.flags,
7374 new_section->named.decl);
7375 break;
7377 case SECTION_UNNAMED:
7378 new_section->unnamed.callback (new_section->unnamed.data);
7379 break;
7381 case SECTION_NOSWITCH:
7382 gcc_unreachable ();
7383 break;
7386 new_section->common.flags |= SECTION_DECLARED;
7389 /* If block symbol SYMBOL has not yet been assigned an offset, place
7390 it at the end of its block. */
7392 void
7393 place_block_symbol (rtx symbol)
7395 unsigned HOST_WIDE_INT size, mask, offset;
7396 struct constant_descriptor_rtx *desc;
7397 unsigned int alignment;
7398 struct object_block *block;
7399 tree decl;
7401 gcc_assert (SYMBOL_REF_BLOCK (symbol));
7402 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7403 return;
7405 /* Work out the symbol's size and alignment. */
7406 if (CONSTANT_POOL_ADDRESS_P (symbol))
7408 desc = SYMBOL_REF_CONSTANT (symbol);
7409 alignment = desc->align;
7410 size = GET_MODE_SIZE (desc->mode);
7412 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7414 decl = SYMBOL_REF_DECL (symbol);
7415 gcc_checking_assert (DECL_IN_CONSTANT_POOL (decl));
7416 alignment = DECL_ALIGN (decl);
7417 size = get_constant_size (DECL_INITIAL (decl));
7418 if ((flag_sanitize & SANITIZE_ADDRESS)
7419 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7420 && asan_protect_global (DECL_INITIAL (decl)))
7422 size += asan_red_zone_size (size);
7423 alignment = MAX (alignment,
7424 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7427 else
7429 struct symtab_node *snode;
7430 decl = SYMBOL_REF_DECL (symbol);
7432 snode = symtab_node::get (decl);
7433 if (snode->alias)
7435 rtx target = DECL_RTL (snode->ultimate_alias_target ()->decl);
7437 gcc_assert (MEM_P (target)
7438 && GET_CODE (XEXP (target, 0)) == SYMBOL_REF
7439 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (target, 0)));
7440 target = XEXP (target, 0);
7441 place_block_symbol (target);
7442 SYMBOL_REF_BLOCK_OFFSET (symbol) = SYMBOL_REF_BLOCK_OFFSET (target);
7443 return;
7445 alignment = get_variable_align (decl);
7446 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7447 if ((flag_sanitize & SANITIZE_ADDRESS)
7448 && asan_protect_global (decl))
7450 size += asan_red_zone_size (size);
7451 alignment = MAX (alignment,
7452 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7456 /* Calculate the object's offset from the start of the block. */
7457 block = SYMBOL_REF_BLOCK (symbol);
7458 mask = alignment / BITS_PER_UNIT - 1;
7459 offset = (block->size + mask) & ~mask;
7460 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7462 /* Record the block's new alignment and size. */
7463 block->alignment = MAX (block->alignment, alignment);
7464 block->size = offset + size;
7466 vec_safe_push (block->objects, symbol);
7469 /* Return the anchor that should be used to address byte offset OFFSET
7470 from the first object in BLOCK. MODEL is the TLS model used
7471 to access it. */
7474 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7475 enum tls_model model)
7477 char label[100];
7478 unsigned int begin, middle, end;
7479 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7480 rtx anchor;
7482 /* Work out the anchor's offset. Use an offset of 0 for the first
7483 anchor so that we don't pessimize the case where we take the address
7484 of a variable at the beginning of the block. This is particularly
7485 useful when a block has only one variable assigned to it.
7487 We try to place anchors RANGE bytes apart, so there can then be
7488 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7489 a ptr_mode offset. With some target settings, the lowest such
7490 anchor might be out of range for the lowest ptr_mode offset;
7491 likewise the highest anchor for the highest offset. Use anchors
7492 at the extreme ends of the ptr_mode range in such cases.
7494 All arithmetic uses unsigned integers in order to avoid
7495 signed overflow. */
7496 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7497 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7498 range = max_offset - min_offset + 1;
7499 if (range == 0)
7500 offset = 0;
7501 else
7503 bias = HOST_WIDE_INT_1U << (GET_MODE_BITSIZE (ptr_mode) - 1);
7504 if (offset < 0)
7506 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7507 delta -= delta % range;
7508 if (delta > bias)
7509 delta = bias;
7510 offset = (HOST_WIDE_INT) (-delta);
7512 else
7514 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7515 delta -= delta % range;
7516 if (delta > bias - 1)
7517 delta = bias - 1;
7518 offset = (HOST_WIDE_INT) delta;
7522 /* Do a binary search to see if there's already an anchor we can use.
7523 Set BEGIN to the new anchor's index if not. */
7524 begin = 0;
7525 end = vec_safe_length (block->anchors);
7526 while (begin != end)
7528 middle = (end + begin) / 2;
7529 anchor = (*block->anchors)[middle];
7530 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7531 end = middle;
7532 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7533 begin = middle + 1;
7534 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7535 end = middle;
7536 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7537 begin = middle + 1;
7538 else
7539 return anchor;
7542 /* Create a new anchor with a unique label. */
7543 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7544 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7545 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7546 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7548 /* Insert it at index BEGIN. */
7549 vec_safe_insert (block->anchors, begin, anchor);
7550 return anchor;
7553 /* Output the objects in BLOCK. */
7555 static void
7556 output_object_block (struct object_block *block)
7558 struct constant_descriptor_rtx *desc;
7559 unsigned int i;
7560 HOST_WIDE_INT offset;
7561 tree decl;
7562 rtx symbol;
7564 if (!block->objects)
7565 return;
7567 /* Switch to the section and make sure that the first byte is
7568 suitably aligned. */
7569 /* Special case VTV comdat sections similar to assemble_variable. */
7570 if (SECTION_STYLE (block->sect) == SECTION_NAMED
7571 && block->sect->named.name
7572 && (strcmp (block->sect->named.name, ".vtable_map_vars") == 0))
7573 handle_vtv_comdat_section (block->sect, block->sect->named.decl);
7574 else
7575 switch_to_section (block->sect);
7577 assemble_align (block->alignment);
7579 /* Define the values of all anchors relative to the current section
7580 position. */
7581 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7582 targetm.asm_out.output_anchor (symbol);
7584 /* Output the objects themselves. */
7585 offset = 0;
7586 FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7588 /* Move to the object's offset, padding with zeros if necessary. */
7589 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7590 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7591 if (CONSTANT_POOL_ADDRESS_P (symbol))
7593 desc = SYMBOL_REF_CONSTANT (symbol);
7594 /* Pass 1 for align as we have already laid out everything in the block.
7595 So aligning shouldn't be necessary. */
7596 output_constant_pool_1 (desc, 1);
7597 offset += GET_MODE_SIZE (desc->mode);
7599 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7601 HOST_WIDE_INT size;
7602 decl = SYMBOL_REF_DECL (symbol);
7603 assemble_constant_contents
7604 (DECL_INITIAL (decl), XSTR (symbol, 0), DECL_ALIGN (decl));
7606 size = get_constant_size (DECL_INITIAL (decl));
7607 offset += size;
7608 if ((flag_sanitize & SANITIZE_ADDRESS)
7609 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7610 && asan_protect_global (DECL_INITIAL (decl)))
7612 size = asan_red_zone_size (size);
7613 assemble_zeros (size);
7614 offset += size;
7617 else
7619 HOST_WIDE_INT size;
7620 decl = SYMBOL_REF_DECL (symbol);
7621 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7622 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7623 offset += size;
7624 if ((flag_sanitize & SANITIZE_ADDRESS)
7625 && asan_protect_global (decl))
7627 size = asan_red_zone_size (size);
7628 assemble_zeros (size);
7629 offset += size;
7635 /* A callback for qsort to compare object_blocks. */
7637 static int
7638 output_object_block_compare (const void *x, const void *y)
7640 object_block *p1 = *(object_block * const*)x;
7641 object_block *p2 = *(object_block * const*)y;
7643 if (p1->sect->common.flags & SECTION_NAMED
7644 && !(p2->sect->common.flags & SECTION_NAMED))
7645 return 1;
7647 if (!(p1->sect->common.flags & SECTION_NAMED)
7648 && p2->sect->common.flags & SECTION_NAMED)
7649 return -1;
7651 if (p1->sect->common.flags & SECTION_NAMED
7652 && p2->sect->common.flags & SECTION_NAMED)
7653 return strcmp (p1->sect->named.name, p2->sect->named.name);
7655 unsigned f1 = p1->sect->common.flags;
7656 unsigned f2 = p2->sect->common.flags;
7657 if (f1 == f2)
7658 return 0;
7659 return f1 < f2 ? -1 : 1;
7662 /* Output the definitions of all object_blocks. */
7664 void
7665 output_object_blocks (void)
7667 vec<object_block *, va_heap> v;
7668 v.create (object_block_htab->elements ());
7669 object_block *obj;
7670 hash_table<object_block_hasher>::iterator hi;
7672 FOR_EACH_HASH_TABLE_ELEMENT (*object_block_htab, obj, object_block *, hi)
7673 v.quick_push (obj);
7675 /* Sort them in order to output them in a deterministic manner,
7676 otherwise we may get .rodata sections in different orders with
7677 and without -g. */
7678 v.qsort (output_object_block_compare);
7679 unsigned i;
7680 FOR_EACH_VEC_ELT (v, i, obj)
7681 output_object_block (obj);
7683 v.release ();
7686 /* This function provides a possible implementation of the
7687 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7688 by -frecord-gcc-switches it creates a new mergeable, string section in the
7689 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7690 contains the switches in ASCII format.
7692 FIXME: This code does not correctly handle double quote characters
7693 that appear inside strings, (it strips them rather than preserving them).
7694 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7695 characters - instead it treats them as sub-string separators. Since
7696 we want to emit NUL strings terminators into the object file we have to use
7697 ASM_OUTPUT_SKIP. */
7700 elf_record_gcc_switches (print_switch_type type, const char * name)
7702 switch (type)
7704 case SWITCH_TYPE_PASSED:
7705 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7706 ASM_OUTPUT_SKIP (asm_out_file, HOST_WIDE_INT_1U);
7707 break;
7709 case SWITCH_TYPE_DESCRIPTIVE:
7710 if (name == NULL)
7712 /* Distinguish between invocations where name is NULL. */
7713 static bool started = false;
7715 if (!started)
7717 section * sec;
7719 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7720 SECTION_DEBUG
7721 | SECTION_MERGE
7722 | SECTION_STRINGS
7723 | (SECTION_ENTSIZE & 1),
7724 NULL);
7725 switch_to_section (sec);
7726 started = true;
7730 default:
7731 break;
7734 /* The return value is currently ignored by the caller, but must be 0.
7735 For -fverbose-asm the return value would be the number of characters
7736 emitted into the assembler file. */
7737 return 0;
7740 /* Emit text to declare externally defined symbols. It is needed to
7741 properly support non-default visibility. */
7742 void
7743 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7744 tree decl,
7745 const char *name ATTRIBUTE_UNUSED)
7747 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7748 set in order to avoid putting out names that are never really
7749 used. Always output visibility specified in the source. */
7750 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7751 && (DECL_VISIBILITY_SPECIFIED (decl)
7752 || targetm.binds_local_p (decl)))
7753 maybe_assemble_visibility (decl);
7756 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7758 void
7759 default_asm_output_source_filename (FILE *file, const char *name)
7761 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7762 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7763 #else
7764 fprintf (file, "\t.file\t");
7765 output_quoted_string (file, name);
7766 putc ('\n', file);
7767 #endif
7770 /* Output a file name in the form wanted by System V. */
7772 void
7773 output_file_directive (FILE *asm_file, const char *input_name)
7775 int len;
7776 const char *na;
7778 if (input_name == NULL)
7779 input_name = "<stdin>";
7780 else
7781 input_name = remap_debug_filename (input_name);
7783 len = strlen (input_name);
7784 na = input_name + len;
7786 /* NA gets INPUT_NAME sans directory names. */
7787 while (na > input_name)
7789 if (IS_DIR_SEPARATOR (na[-1]))
7790 break;
7791 na--;
7794 targetm.asm_out.output_source_filename (asm_file, na);
7797 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7798 EXP. */
7800 make_debug_expr_from_rtl (const_rtx exp)
7802 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7803 machine_mode mode = GET_MODE (exp);
7804 rtx dval;
7806 DECL_ARTIFICIAL (ddecl) = 1;
7807 if (REG_P (exp) && REG_EXPR (exp))
7808 type = TREE_TYPE (REG_EXPR (exp));
7809 else if (MEM_P (exp) && MEM_EXPR (exp))
7810 type = TREE_TYPE (MEM_EXPR (exp));
7811 else
7812 type = NULL_TREE;
7813 if (type && TYPE_MODE (type) == mode)
7814 TREE_TYPE (ddecl) = type;
7815 else
7816 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7817 SET_DECL_MODE (ddecl, mode);
7818 dval = gen_rtx_DEBUG_EXPR (mode);
7819 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7820 SET_DECL_RTL (ddecl, dval);
7821 return dval;
7824 #ifdef ELF_ASCII_ESCAPES
7825 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7827 void
7828 default_elf_asm_output_limited_string (FILE *f, const char *s)
7830 int escape;
7831 unsigned char c;
7833 fputs (STRING_ASM_OP, f);
7834 putc ('"', f);
7835 while (*s != '\0')
7837 c = *s;
7838 escape = ELF_ASCII_ESCAPES[c];
7839 switch (escape)
7841 case 0:
7842 putc (c, f);
7843 break;
7844 case 1:
7845 putc ('\\', f);
7846 putc ('0'+((c>>6)&7), f);
7847 putc ('0'+((c>>3)&7), f);
7848 putc ('0'+(c&7), f);
7849 break;
7850 default:
7851 putc ('\\', f);
7852 putc (escape, f);
7853 break;
7855 s++;
7857 putc ('\"', f);
7858 putc ('\n', f);
7861 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7863 void
7864 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7866 const char *limit = s + len;
7867 const char *last_null = NULL;
7868 unsigned bytes_in_chunk = 0;
7869 unsigned char c;
7870 int escape;
7872 for (; s < limit; s++)
7874 const char *p;
7876 if (bytes_in_chunk >= 60)
7878 putc ('\"', f);
7879 putc ('\n', f);
7880 bytes_in_chunk = 0;
7883 if (s > last_null)
7885 for (p = s; p < limit && *p != '\0'; p++)
7886 continue;
7887 last_null = p;
7889 else
7890 p = last_null;
7892 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7894 if (bytes_in_chunk > 0)
7896 putc ('\"', f);
7897 putc ('\n', f);
7898 bytes_in_chunk = 0;
7901 default_elf_asm_output_limited_string (f, s);
7902 s = p;
7904 else
7906 if (bytes_in_chunk == 0)
7907 fputs (ASCII_DATA_ASM_OP "\"", f);
7909 c = *s;
7910 escape = ELF_ASCII_ESCAPES[c];
7911 switch (escape)
7913 case 0:
7914 putc (c, f);
7915 bytes_in_chunk++;
7916 break;
7917 case 1:
7918 putc ('\\', f);
7919 putc ('0'+((c>>6)&7), f);
7920 putc ('0'+((c>>3)&7), f);
7921 putc ('0'+(c&7), f);
7922 bytes_in_chunk += 4;
7923 break;
7924 default:
7925 putc ('\\', f);
7926 putc (escape, f);
7927 bytes_in_chunk += 2;
7928 break;
7934 if (bytes_in_chunk > 0)
7936 putc ('\"', f);
7937 putc ('\n', f);
7940 #endif
7942 static GTY(()) section *elf_init_array_section;
7943 static GTY(()) section *elf_fini_array_section;
7945 static section *
7946 get_elf_initfini_array_priority_section (int priority,
7947 bool constructor_p)
7949 section *sec;
7950 if (priority != DEFAULT_INIT_PRIORITY)
7952 char buf[18];
7953 sprintf (buf, "%s.%.5u",
7954 constructor_p ? ".init_array" : ".fini_array",
7955 priority);
7956 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7958 else
7960 if (constructor_p)
7962 if (elf_init_array_section == NULL)
7963 elf_init_array_section
7964 = get_section (".init_array",
7965 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7966 sec = elf_init_array_section;
7968 else
7970 if (elf_fini_array_section == NULL)
7971 elf_fini_array_section
7972 = get_section (".fini_array",
7973 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7974 sec = elf_fini_array_section;
7977 return sec;
7980 /* Use .init_array section for constructors. */
7982 void
7983 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7985 section *sec = get_elf_initfini_array_priority_section (priority,
7986 true);
7987 assemble_addr_to_section (symbol, sec);
7990 /* Use .fini_array section for destructors. */
7992 void
7993 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7995 section *sec = get_elf_initfini_array_priority_section (priority,
7996 false);
7997 assemble_addr_to_section (symbol, sec);
8000 /* Default TARGET_ASM_OUTPUT_IDENT hook.
8002 This is a bit of a cheat. The real default is a no-op, but this
8003 hook is the default for all targets with a .ident directive. */
8005 void
8006 default_asm_output_ident_directive (const char *ident_str)
8008 const char *ident_asm_op = "\t.ident\t";
8010 /* If we are still in the front end, do not write out the string
8011 to asm_out_file. Instead, add a fake top-level asm statement.
8012 This allows the front ends to use this hook without actually
8013 writing to asm_out_file, to handle #ident or Pragma Ident. */
8014 if (symtab->state == PARSING)
8016 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
8017 symtab->finalize_toplevel_asm (build_string (strlen (buf), buf));
8019 else
8020 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
8024 /* This function ensures that vtable_map variables are not only
8025 in the comdat section, but that each variable has its own unique
8026 comdat name. Without this the variables end up in the same section
8027 with a single comdat name.
8029 FIXME: resolve_unique_section needs to deal better with
8030 decls with both DECL_SECTION_NAME and DECL_ONE_ONLY. Once
8031 that is fixed, this if-else statement can be replaced with
8032 a single call to "switch_to_section (sect)". */
8034 static void
8035 handle_vtv_comdat_section (section *sect, const_tree decl ATTRIBUTE_UNUSED)
8037 #if defined (OBJECT_FORMAT_ELF)
8038 targetm.asm_out.named_section (sect->named.name,
8039 sect->named.common.flags
8040 | SECTION_LINKONCE,
8041 DECL_NAME (decl));
8042 in_section = sect;
8043 #else
8044 /* Neither OBJECT_FORMAT_PE, nor OBJECT_FORMAT_COFF is set here.
8045 Therefore the following check is used.
8046 In case a the target is PE or COFF a comdat group section
8047 is created, e.g. .vtable_map_vars$foo. The linker places
8048 everything in .vtable_map_vars at the end.
8050 A fix could be made in
8051 gcc/config/i386/winnt.c: i386_pe_unique_section. */
8052 if (TARGET_PECOFF)
8054 char *name;
8056 if (TREE_CODE (DECL_NAME (decl)) == IDENTIFIER_NODE)
8057 name = ACONCAT ((sect->named.name, "$",
8058 IDENTIFIER_POINTER (DECL_NAME (decl)), NULL));
8059 else
8060 name = ACONCAT ((sect->named.name, "$",
8061 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (DECL_NAME (decl))),
8062 NULL));
8064 targetm.asm_out.named_section (name,
8065 sect->named.common.flags
8066 | SECTION_LINKONCE,
8067 DECL_NAME (decl));
8068 in_section = sect;
8070 else
8071 switch_to_section (sect);
8072 #endif
8075 #include "gt-varasm.h"