PR bootstrap/63496
[official-gcc.git] / gcc / varasm.c
blobabb743b6b8383be3571aeb9a475b88bd04ec86c4
1 /* Output variables, constants and external declarations, for GNU compiler.
2 Copyright (C) 1987-2014 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 "tm.h"
32 #include "rtl.h"
33 #include "tree.h"
34 #include "stor-layout.h"
35 #include "stringpool.h"
36 #include "varasm.h"
37 #include "flags.h"
38 #include "function.h"
39 #include "expr.h"
40 #include "hard-reg-set.h"
41 #include "regs.h"
42 #include "output.h"
43 #include "diagnostic-core.h"
44 #include "hashtab.h"
45 #include "ggc.h"
46 #include "langhooks.h"
47 #include "tm_p.h"
48 #include "debug.h"
49 #include "target.h"
50 #include "common/common-target.h"
51 #include "targhooks.h"
52 #include "cgraph.h"
53 #include "hash-set.h"
54 #include "asan.h"
55 #include "basic-block.h"
56 #include "rtl-iter.h"
58 #ifdef XCOFF_DEBUGGING_INFO
59 #include "xcoffout.h" /* Needed for external data
60 declarations for e.g. AIX 4.x. */
61 #endif
63 /* The (assembler) name of the first globally-visible object output. */
64 extern GTY(()) const char *first_global_object_name;
65 extern GTY(()) const char *weak_global_object_name;
67 const char *first_global_object_name;
68 const char *weak_global_object_name;
70 struct addr_const;
71 struct constant_descriptor_rtx;
72 struct rtx_constant_pool;
74 #define n_deferred_constants (crtl->varasm.deferred_constants)
76 /* Number for making the label on the next
77 constant that is stored in memory. */
79 static GTY(()) int const_labelno;
81 /* Carry information from ASM_DECLARE_OBJECT_NAME
82 to ASM_FINISH_DECLARE_OBJECT. */
84 int size_directive_output;
86 /* The last decl for which assemble_variable was called,
87 if it did ASM_DECLARE_OBJECT_NAME.
88 If the last call to assemble_variable didn't do that,
89 this holds 0. */
91 tree last_assemble_variable_decl;
93 /* The following global variable indicates if the first basic block
94 in a function belongs to the cold partition or not. */
96 bool first_function_block_is_cold;
98 /* We give all constants their own alias set. Perhaps redundant with
99 MEM_READONLY_P, but pre-dates it. */
101 static alias_set_type const_alias_set;
103 /* Whether we saw any functions with no_split_stack. */
105 static bool saw_no_split_stack;
107 static const char *strip_reg_name (const char *);
108 static int contains_pointers_p (tree);
109 #ifdef ASM_OUTPUT_EXTERNAL
110 static bool incorporeal_function_p (tree);
111 #endif
112 static void decode_addr_const (tree, struct addr_const *);
113 static hashval_t const_hash_1 (const tree);
114 static int compare_constant (const tree, const tree);
115 static void output_constant_def_contents (rtx);
116 static void output_addressed_constants (tree);
117 static unsigned HOST_WIDE_INT output_constant (tree, unsigned HOST_WIDE_INT,
118 unsigned int);
119 static void globalize_decl (tree);
120 static bool decl_readonly_section_1 (enum section_category);
121 #ifdef BSS_SECTION_ASM_OP
122 #ifdef ASM_OUTPUT_ALIGNED_BSS
123 static void asm_output_aligned_bss (FILE *, tree, const char *,
124 unsigned HOST_WIDE_INT, int)
125 ATTRIBUTE_UNUSED;
126 #endif
127 #endif /* BSS_SECTION_ASM_OP */
128 static void mark_weak (tree);
129 static void output_constant_pool (const char *, tree);
131 /* Well-known sections, each one associated with some sort of *_ASM_OP. */
132 section *text_section;
133 section *data_section;
134 section *readonly_data_section;
135 section *sdata_section;
136 section *ctors_section;
137 section *dtors_section;
138 section *bss_section;
139 section *sbss_section;
141 /* Various forms of common section. All are guaranteed to be nonnull. */
142 section *tls_comm_section;
143 section *comm_section;
144 section *lcomm_section;
146 /* A SECTION_NOSWITCH section used for declaring global BSS variables.
147 May be null. */
148 section *bss_noswitch_section;
150 /* The section that holds the main exception table, when known. The section
151 is set either by the target's init_sections hook or by the first call to
152 switch_to_exception_section. */
153 section *exception_section;
155 /* The section that holds the DWARF2 frame unwind information, when known.
156 The section is set either by the target's init_sections hook or by the
157 first call to switch_to_eh_frame_section. */
158 section *eh_frame_section;
160 /* asm_out_file's current section. This is NULL if no section has yet
161 been selected or if we lose track of what the current section is. */
162 section *in_section;
164 /* True if code for the current function is currently being directed
165 at the cold section. */
166 bool in_cold_section_p;
168 /* A linked list of all the unnamed sections. */
169 static GTY(()) section *unnamed_sections;
171 /* Return a nonzero value if DECL has a section attribute. */
172 #define IN_NAMED_SECTION(DECL) \
173 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \
174 && DECL_SECTION_NAME (DECL) != NULL)
176 struct section_hasher : ggc_hasher<section *>
178 typedef const char *compare_type;
180 static hashval_t hash (section *);
181 static bool equal (section *, const char *);
184 /* Hash table of named sections. */
185 static GTY(()) hash_table<section_hasher> *section_htab;
187 struct object_block_hasher : ggc_hasher<object_block *>
189 typedef const section *compare_type;
191 static hashval_t hash (object_block *);
192 static bool equal (object_block *, const section *);
195 /* A table of object_blocks, indexed by section. */
196 static GTY(()) hash_table<object_block_hasher> *object_block_htab;
198 /* The next number to use for internal anchor labels. */
199 static GTY(()) int anchor_labelno;
201 /* A pool of constants that can be shared between functions. */
202 static GTY(()) struct rtx_constant_pool *shared_constant_pool;
204 /* Helper routines for maintaining section_htab. */
206 bool
207 section_hasher::equal (section *old, const char *new_name)
209 return strcmp (old->named.name, new_name) == 0;
212 hashval_t
213 section_hasher::hash (section *old)
215 return htab_hash_string (old->named.name);
218 /* Return a hash value for section SECT. */
220 static hashval_t
221 hash_section (section *sect)
223 if (sect->common.flags & SECTION_NAMED)
224 return htab_hash_string (sect->named.name);
225 return sect->common.flags;
228 /* Helper routines for maintaining object_block_htab. */
230 inline bool
231 object_block_hasher::equal (object_block *old, const section *new_section)
233 return old->sect == new_section;
236 hashval_t
237 object_block_hasher::hash (object_block *old)
239 return hash_section (old->sect);
242 /* Return a new unnamed section with the given fields. */
244 section *
245 get_unnamed_section (unsigned int flags, void (*callback) (const void *),
246 const void *data)
248 section *sect;
250 sect = ggc_alloc<section> ();
251 sect->unnamed.common.flags = flags | SECTION_UNNAMED;
252 sect->unnamed.callback = callback;
253 sect->unnamed.data = data;
254 sect->unnamed.next = unnamed_sections;
256 unnamed_sections = sect;
257 return sect;
260 /* Return a SECTION_NOSWITCH section with the given fields. */
262 static section *
263 get_noswitch_section (unsigned int flags, noswitch_section_callback callback)
265 section *sect;
267 sect = ggc_alloc<section> ();
268 sect->noswitch.common.flags = flags | SECTION_NOSWITCH;
269 sect->noswitch.callback = callback;
271 return sect;
274 /* Return the named section structure associated with NAME. Create
275 a new section with the given fields if no such structure exists. */
277 section *
278 get_section (const char *name, unsigned int flags, tree decl)
280 section *sect, **slot;
282 slot = section_htab->find_slot_with_hash (name, htab_hash_string (name),
283 INSERT);
284 flags |= SECTION_NAMED;
285 if (*slot == NULL)
287 sect = ggc_alloc<section> ();
288 sect->named.common.flags = flags;
289 sect->named.name = ggc_strdup (name);
290 sect->named.decl = decl;
291 *slot = sect;
293 else
295 sect = *slot;
296 if ((sect->common.flags & ~SECTION_DECLARED) != flags
297 && ((sect->common.flags | flags) & SECTION_OVERRIDE) == 0)
299 /* It is fine if one of the section flags is
300 SECTION_WRITE | SECTION_RELRO and the other has none of these
301 flags (i.e. read-only) in named sections and either the
302 section hasn't been declared yet or has been declared as writable.
303 In that case just make sure the resulting flags are
304 SECTION_WRITE | SECTION_RELRO, ie. writable only because of
305 relocations. */
306 if (((sect->common.flags ^ flags) & (SECTION_WRITE | SECTION_RELRO))
307 == (SECTION_WRITE | SECTION_RELRO)
308 && (sect->common.flags
309 & ~(SECTION_DECLARED | SECTION_WRITE | SECTION_RELRO))
310 == (flags & ~(SECTION_WRITE | SECTION_RELRO))
311 && ((sect->common.flags & SECTION_DECLARED) == 0
312 || (sect->common.flags & SECTION_WRITE)))
314 sect->common.flags |= (SECTION_WRITE | SECTION_RELRO);
315 return sect;
317 /* Sanity check user variables for flag changes. */
318 if (sect->named.decl != NULL
319 && DECL_P (sect->named.decl)
320 && decl != sect->named.decl)
322 if (decl != NULL && DECL_P (decl))
323 error ("%+D causes a section type conflict with %D",
324 decl, sect->named.decl);
325 else
326 error ("section type conflict with %D", sect->named.decl);
327 inform (DECL_SOURCE_LOCATION (sect->named.decl),
328 "%qD was declared here", sect->named.decl);
330 else if (decl != NULL && DECL_P (decl))
331 error ("%+D causes a section type conflict", decl);
332 else
333 error ("section type conflict");
334 /* Make sure we don't error about one section multiple times. */
335 sect->common.flags |= SECTION_OVERRIDE;
338 return sect;
341 /* Return true if the current compilation mode benefits from having
342 objects grouped into blocks. */
344 static bool
345 use_object_blocks_p (void)
347 return flag_section_anchors;
350 /* Return the object_block structure for section SECT. Create a new
351 structure if we haven't created one already. Return null if SECT
352 itself is null. */
354 static struct object_block *
355 get_block_for_section (section *sect)
357 struct object_block *block;
359 if (sect == NULL)
360 return NULL;
362 object_block **slot
363 = object_block_htab->find_slot_with_hash (sect, hash_section (sect),
364 INSERT);
365 block = *slot;
366 if (block == NULL)
368 block = ggc_cleared_alloc<object_block> ();
369 block->sect = sect;
370 *slot = block;
372 return block;
375 /* Create a symbol with label LABEL and place it at byte offset
376 OFFSET in BLOCK. OFFSET can be negative if the symbol's offset
377 is not yet known. LABEL must be a garbage-collected string. */
379 static rtx
380 create_block_symbol (const char *label, struct object_block *block,
381 HOST_WIDE_INT offset)
383 rtx symbol;
384 unsigned int size;
386 /* Create the extended SYMBOL_REF. */
387 size = RTX_HDR_SIZE + sizeof (struct block_symbol);
388 symbol = (rtx) ggc_internal_alloc (size);
390 /* Initialize the normal SYMBOL_REF fields. */
391 memset (symbol, 0, size);
392 PUT_CODE (symbol, SYMBOL_REF);
393 PUT_MODE (symbol, Pmode);
394 XSTR (symbol, 0) = label;
395 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_HAS_BLOCK_INFO;
397 /* Initialize the block_symbol stuff. */
398 SYMBOL_REF_BLOCK (symbol) = block;
399 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
401 return symbol;
404 /* Return a section with a particular name and with whatever SECTION_*
405 flags section_type_flags deems appropriate. The name of the section
406 is taken from NAME if nonnull, otherwise it is taken from DECL's
407 DECL_SECTION_NAME. DECL is the decl associated with the section
408 (see the section comment for details) and RELOC is as for
409 section_type_flags. */
411 section *
412 get_named_section (tree decl, const char *name, int reloc)
414 unsigned int flags;
416 if (name == NULL)
418 gcc_assert (decl && DECL_P (decl) && DECL_SECTION_NAME (decl));
419 name = DECL_SECTION_NAME (decl);
422 flags = targetm.section_type_flags (decl, name, reloc);
423 return get_section (name, flags, decl);
426 /* Worker for resolve_unique_section. */
428 static bool
429 set_implicit_section (struct symtab_node *n, void *data ATTRIBUTE_UNUSED)
431 n->implicit_section = true;
432 return false;
435 /* If required, set DECL_SECTION_NAME to a unique name. */
437 void
438 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
439 int flag_function_or_data_sections)
441 if (DECL_SECTION_NAME (decl) == NULL
442 && targetm_common.have_named_sections
443 && (flag_function_or_data_sections
444 || DECL_COMDAT_GROUP (decl)))
446 targetm.asm_out.unique_section (decl, reloc);
447 if (DECL_SECTION_NAME (decl))
448 symtab_node::get (decl)->call_for_symbol_and_aliases
449 (set_implicit_section, NULL, true);
453 #ifdef BSS_SECTION_ASM_OP
455 #ifdef ASM_OUTPUT_ALIGNED_BSS
457 /* Utility function for targets to use in implementing
458 ASM_OUTPUT_ALIGNED_BSS.
459 ??? It is believed that this function will work in most cases so such
460 support is localized here. */
462 static void
463 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
464 const char *name, unsigned HOST_WIDE_INT size,
465 int align)
467 switch_to_section (bss_section);
468 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
469 #ifdef ASM_DECLARE_OBJECT_NAME
470 last_assemble_variable_decl = decl;
471 ASM_DECLARE_OBJECT_NAME (file, name, decl);
472 #else
473 /* Standard thing is just output label for the object. */
474 ASM_OUTPUT_LABEL (file, name);
475 #endif /* ASM_DECLARE_OBJECT_NAME */
476 ASM_OUTPUT_SKIP (file, size ? size : 1);
479 #endif
481 #endif /* BSS_SECTION_ASM_OP */
483 #ifndef USE_SELECT_SECTION_FOR_FUNCTIONS
484 /* Return the hot section for function DECL. Return text_section for
485 null DECLs. */
487 static section *
488 hot_function_section (tree decl)
490 if (decl != NULL_TREE
491 && DECL_SECTION_NAME (decl) != NULL
492 && targetm_common.have_named_sections)
493 return get_named_section (decl, NULL, 0);
494 else
495 return text_section;
497 #endif
499 /* Return section for TEXT_SECTION_NAME if DECL or DECL_SECTION_NAME (DECL)
500 is NULL.
502 When DECL_SECTION_NAME is non-NULL and it is implicit section and
503 NAMED_SECTION_SUFFIX is non-NULL, then produce section called
504 concatenate the name with NAMED_SECTION_SUFFIX.
505 Otherwise produce "TEXT_SECTION_NAME.IMPLICIT_NAME". */
507 section *
508 get_named_text_section (tree decl,
509 const char *text_section_name,
510 const char *named_section_suffix)
512 if (decl && DECL_SECTION_NAME (decl))
514 if (named_section_suffix)
516 const char *dsn = DECL_SECTION_NAME (decl);
517 const char *stripped_name;
518 char *name, *buffer;
520 name = (char *) alloca (strlen (dsn) + 1);
521 memcpy (name, dsn,
522 strlen (dsn) + 1);
524 stripped_name = targetm.strip_name_encoding (name);
526 buffer = ACONCAT ((stripped_name, named_section_suffix, NULL));
527 return get_named_section (decl, buffer, 0);
529 else if (symtab_node::get (decl)->implicit_section)
531 const char *name;
533 /* Do not try to split gnu_linkonce functions. This gets somewhat
534 slipperly. */
535 if (DECL_COMDAT_GROUP (decl) && !HAVE_COMDAT_GROUP)
536 return NULL;
537 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
538 name = targetm.strip_name_encoding (name);
539 return get_named_section (decl, ACONCAT ((text_section_name, ".",
540 name, NULL)), 0);
542 else
543 return NULL;
545 return get_named_section (decl, text_section_name, 0);
548 /* Choose named function section based on its frequency. */
550 section *
551 default_function_section (tree decl, enum node_frequency freq,
552 bool startup, bool exit)
554 #if defined HAVE_LD_EH_GC_SECTIONS && defined HAVE_LD_EH_GC_SECTIONS_BUG
555 /* Old GNU linkers have buggy --gc-section support, which sometimes
556 results in .gcc_except_table* sections being garbage collected. */
557 if (decl
558 && symtab_node::get (decl)->implicit_section)
559 return NULL;
560 #endif
562 if (!flag_reorder_functions
563 || !targetm_common.have_named_sections)
564 return NULL;
565 /* Startup code should go to startup subsection unless it is
566 unlikely executed (this happens especially with function splitting
567 where we can split away unnecessary parts of static constructors. */
568 if (startup && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
570 /* If we do have a profile or(and) LTO phase is executed, we do not need
571 these ELF section. */
572 if (!in_lto_p || !flag_profile_values)
573 return get_named_text_section (decl, ".text.startup", NULL);
574 else
575 return NULL;
578 /* Similarly for exit. */
579 if (exit && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
580 return get_named_text_section (decl, ".text.exit", NULL);
582 /* Group cold functions together, similarly for hot code. */
583 switch (freq)
585 case NODE_FREQUENCY_UNLIKELY_EXECUTED:
586 return get_named_text_section (decl, ".text.unlikely", NULL);
587 case NODE_FREQUENCY_HOT:
588 /* If we do have a profile or(and) LTO phase is executed, we do not need
589 these ELF section. */
590 if (!in_lto_p || !flag_profile_values)
591 return get_named_text_section (decl, ".text.hot", NULL);
592 default:
593 return NULL;
597 /* Return the section for function DECL.
599 If DECL is NULL_TREE, return the text section. We can be passed
600 NULL_TREE under some circumstances by dbxout.c at least.
602 If FORCE_COLD is true, return cold function section ignoring
603 the frequency info of cgraph_node. */
605 static section *
606 function_section_1 (tree decl, bool force_cold)
608 section *section = NULL;
609 enum node_frequency freq = NODE_FREQUENCY_NORMAL;
610 bool startup = false, exit = false;
612 if (decl)
614 struct cgraph_node *node = cgraph_node::get (decl);
616 if (node)
618 freq = node->frequency;
619 startup = node->only_called_at_startup;
620 exit = node->only_called_at_exit;
623 if (force_cold)
624 freq = NODE_FREQUENCY_UNLIKELY_EXECUTED;
626 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
627 if (decl != NULL_TREE
628 && DECL_SECTION_NAME (decl) != NULL)
630 if (targetm.asm_out.function_section)
631 section = targetm.asm_out.function_section (decl, freq,
632 startup, exit);
633 if (section)
634 return section;
635 return get_named_section (decl, NULL, 0);
637 else
638 return targetm.asm_out.select_section
639 (decl, freq == NODE_FREQUENCY_UNLIKELY_EXECUTED,
640 DECL_ALIGN (decl));
641 #else
642 if (targetm.asm_out.function_section)
643 section = targetm.asm_out.function_section (decl, freq, startup, exit);
644 if (section)
645 return section;
646 return hot_function_section (decl);
647 #endif
650 /* Return the section for function DECL.
652 If DECL is NULL_TREE, return the text section. We can be passed
653 NULL_TREE under some circumstances by dbxout.c at least. */
655 section *
656 function_section (tree decl)
658 /* Handle cases where function splitting code decides
659 to put function entry point into unlikely executed section
660 despite the fact that the function itself is not cold
661 (i.e. it is called rarely but contains a hot loop that is
662 better to live in hot subsection for the code locality). */
663 return function_section_1 (decl,
664 first_function_block_is_cold);
667 /* Return the section for the current function, take IN_COLD_SECTION_P
668 into account. */
670 section *
671 current_function_section (void)
673 return function_section_1 (current_function_decl, in_cold_section_p);
676 /* Tell assembler to switch to unlikely-to-be-executed text section. */
678 section *
679 unlikely_text_section (void)
681 return function_section_1 (current_function_decl, true);
684 /* When called within a function context, return true if the function
685 has been assigned a cold text section and if SECT is that section.
686 When called outside a function context, return true if SECT is the
687 default cold section. */
689 bool
690 unlikely_text_section_p (section *sect)
692 return sect == function_section_1 (current_function_decl, true);
695 /* Return the read-only data section associated with function DECL. */
697 section *
698 default_function_rodata_section (tree decl)
700 if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
702 const char *name = DECL_SECTION_NAME (decl);
704 if (DECL_COMDAT_GROUP (decl) && HAVE_COMDAT_GROUP)
706 const char *dot;
707 size_t len;
708 char* rname;
710 dot = strchr (name + 1, '.');
711 if (!dot)
712 dot = name;
713 len = strlen (dot) + 8;
714 rname = (char *) alloca (len);
716 strcpy (rname, ".rodata");
717 strcat (rname, dot);
718 return get_section (rname, SECTION_LINKONCE, decl);
720 /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo. */
721 else if (DECL_COMDAT_GROUP (decl)
722 && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
724 size_t len = strlen (name) + 1;
725 char *rname = (char *) alloca (len);
727 memcpy (rname, name, len);
728 rname[14] = 'r';
729 return get_section (rname, SECTION_LINKONCE, decl);
731 /* For .text.foo we want to use .rodata.foo. */
732 else if (flag_function_sections && flag_data_sections
733 && strncmp (name, ".text.", 6) == 0)
735 size_t len = strlen (name) + 1;
736 char *rname = (char *) alloca (len + 2);
738 memcpy (rname, ".rodata", 7);
739 memcpy (rname + 7, name + 5, len - 5);
740 return get_section (rname, 0, decl);
744 return readonly_data_section;
747 /* Return the read-only data section associated with function DECL
748 for targets where that section should be always the single
749 readonly data section. */
751 section *
752 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
754 return readonly_data_section;
757 /* Return the section to use for string merging. */
759 static section *
760 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
761 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
762 unsigned int flags ATTRIBUTE_UNUSED)
764 HOST_WIDE_INT len;
766 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
767 && TREE_CODE (decl) == STRING_CST
768 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
769 && align <= 256
770 && (len = int_size_in_bytes (TREE_TYPE (decl))) > 0
771 && TREE_STRING_LENGTH (decl) >= len)
773 enum machine_mode mode;
774 unsigned int modesize;
775 const char *str;
776 HOST_WIDE_INT i;
777 int j, unit;
778 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
779 char *name = (char *) alloca (strlen (prefix) + 30);
781 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
782 modesize = GET_MODE_BITSIZE (mode);
783 if (modesize >= 8 && modesize <= 256
784 && (modesize & (modesize - 1)) == 0)
786 if (align < modesize)
787 align = modesize;
789 str = TREE_STRING_POINTER (decl);
790 unit = GET_MODE_SIZE (mode);
792 /* Check for embedded NUL characters. */
793 for (i = 0; i < len; i += unit)
795 for (j = 0; j < unit; j++)
796 if (str[i + j] != '\0')
797 break;
798 if (j == unit)
799 break;
801 if (i == len - unit)
803 sprintf (name, "%s.str%d.%d", prefix,
804 modesize / 8, (int) (align / 8));
805 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
806 return get_section (name, flags, NULL);
811 return readonly_data_section;
814 /* Return the section to use for constant merging. */
816 section *
817 mergeable_constant_section (enum machine_mode mode ATTRIBUTE_UNUSED,
818 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
819 unsigned int flags ATTRIBUTE_UNUSED)
821 unsigned int modesize = GET_MODE_BITSIZE (mode);
823 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
824 && mode != VOIDmode
825 && mode != BLKmode
826 && modesize <= align
827 && align >= 8
828 && align <= 256
829 && (align & (align - 1)) == 0)
831 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
832 char *name = (char *) alloca (strlen (prefix) + 30);
834 sprintf (name, "%s.cst%d", prefix, (int) (align / 8));
835 flags |= (align / 8) | SECTION_MERGE;
836 return get_section (name, flags, NULL);
838 return readonly_data_section;
841 /* Given NAME, a putative register name, discard any customary prefixes. */
843 static const char *
844 strip_reg_name (const char *name)
846 #ifdef REGISTER_PREFIX
847 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
848 name += strlen (REGISTER_PREFIX);
849 #endif
850 if (name[0] == '%' || name[0] == '#')
851 name++;
852 return name;
855 /* The user has asked for a DECL to have a particular name. Set (or
856 change) it in such a way that we don't prefix an underscore to
857 it. */
858 void
859 set_user_assembler_name (tree decl, const char *name)
861 char *starred = (char *) alloca (strlen (name) + 2);
862 starred[0] = '*';
863 strcpy (starred + 1, name);
864 symtab->change_decl_assembler_name (decl, get_identifier (starred));
865 SET_DECL_RTL (decl, NULL_RTX);
868 /* Decode an `asm' spec for a declaration as a register name.
869 Return the register number, or -1 if nothing specified,
870 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
871 or -3 if ASMSPEC is `cc' and is not recognized,
872 or -4 if ASMSPEC is `memory' and is not recognized.
873 Accept an exact spelling or a decimal number.
874 Prefixes such as % are optional. */
877 decode_reg_name_and_count (const char *asmspec, int *pnregs)
879 /* Presume just one register is clobbered. */
880 *pnregs = 1;
882 if (asmspec != 0)
884 int i;
886 /* Get rid of confusing prefixes. */
887 asmspec = strip_reg_name (asmspec);
889 /* Allow a decimal number as a "register name". */
890 for (i = strlen (asmspec) - 1; i >= 0; i--)
891 if (! ISDIGIT (asmspec[i]))
892 break;
893 if (asmspec[0] != 0 && i < 0)
895 i = atoi (asmspec);
896 if (i < FIRST_PSEUDO_REGISTER && i >= 0 && reg_names[i][0])
897 return i;
898 else
899 return -2;
902 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
903 if (reg_names[i][0]
904 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
905 return i;
907 #ifdef OVERLAPPING_REGISTER_NAMES
909 static const struct
911 const char *const name;
912 const int number;
913 const int nregs;
914 } table[] = OVERLAPPING_REGISTER_NAMES;
916 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
917 if (table[i].name[0]
918 && ! strcmp (asmspec, table[i].name))
920 *pnregs = table[i].nregs;
921 return table[i].number;
924 #endif /* OVERLAPPING_REGISTER_NAMES */
926 #ifdef ADDITIONAL_REGISTER_NAMES
928 static const struct { const char *const name; const int number; } table[]
929 = ADDITIONAL_REGISTER_NAMES;
931 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
932 if (table[i].name[0]
933 && ! strcmp (asmspec, table[i].name)
934 && reg_names[table[i].number][0])
935 return table[i].number;
937 #endif /* ADDITIONAL_REGISTER_NAMES */
939 if (!strcmp (asmspec, "memory"))
940 return -4;
942 if (!strcmp (asmspec, "cc"))
943 return -3;
945 return -2;
948 return -1;
952 decode_reg_name (const char *name)
954 int count;
955 return decode_reg_name_and_count (name, &count);
959 /* Return true if DECL's initializer is suitable for a BSS section. */
961 bool
962 bss_initializer_p (const_tree decl)
964 return (DECL_INITIAL (decl) == NULL
965 /* In LTO we have no errors in program; error_mark_node is used
966 to mark offlined constructors. */
967 || (DECL_INITIAL (decl) == error_mark_node
968 && !in_lto_p)
969 || (flag_zero_initialized_in_bss
970 /* Leave constant zeroes in .rodata so they
971 can be shared. */
972 && !TREE_READONLY (decl)
973 && initializer_zerop (DECL_INITIAL (decl))));
976 /* Compute the alignment of variable specified by DECL.
977 DONT_OUTPUT_DATA is from assemble_variable. */
979 void
980 align_variable (tree decl, bool dont_output_data)
982 unsigned int align = DECL_ALIGN (decl);
984 /* In the case for initialing an array whose length isn't specified,
985 where we have not yet been able to do the layout,
986 figure out the proper alignment now. */
987 if (dont_output_data && DECL_SIZE (decl) == 0
988 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
989 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
991 /* Some object file formats have a maximum alignment which they support.
992 In particular, a.out format supports a maximum alignment of 4. */
993 if (align > MAX_OFILE_ALIGNMENT)
995 error ("alignment of %q+D is greater than maximum object "
996 "file alignment %d", decl,
997 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
998 align = MAX_OFILE_ALIGNMENT;
1001 if (! DECL_USER_ALIGN (decl))
1003 #ifdef DATA_ABI_ALIGNMENT
1004 unsigned int data_abi_align
1005 = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1006 /* For backwards compatibility, don't assume the ABI alignment for
1007 TLS variables. */
1008 if (! DECL_THREAD_LOCAL_P (decl) || data_abi_align <= BITS_PER_WORD)
1009 align = data_abi_align;
1010 #endif
1012 /* On some machines, it is good to increase alignment sometimes.
1013 But as DECL_ALIGN is used both for actually emitting the variable
1014 and for code accessing the variable as guaranteed alignment, we
1015 can only increase the alignment if it is a performance optimization
1016 if the references to it must bind to the current definition. */
1017 if (decl_binds_to_current_def_p (decl)
1018 && !DECL_VIRTUAL_P (decl))
1020 #ifdef DATA_ALIGNMENT
1021 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1022 /* Don't increase alignment too much for TLS variables - TLS space
1023 is too precious. */
1024 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1025 align = data_align;
1026 #endif
1027 #ifdef CONSTANT_ALIGNMENT
1028 if (DECL_INITIAL (decl) != 0
1029 /* In LTO we have no errors in program; error_mark_node is used
1030 to mark offlined constructors. */
1031 && (in_lto_p || DECL_INITIAL (decl) != error_mark_node))
1033 unsigned int const_align
1034 = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
1035 /* Don't increase alignment too much for TLS variables - TLS
1036 space is too precious. */
1037 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1038 align = const_align;
1040 #endif
1044 /* Reset the alignment in case we have made it tighter, so we can benefit
1045 from it in get_pointer_alignment. */
1046 DECL_ALIGN (decl) = align;
1049 /* Return DECL_ALIGN (decl), possibly increased for optimization purposes
1050 beyond what align_variable returned. */
1052 static unsigned int
1053 get_variable_align (tree decl)
1055 unsigned int align = DECL_ALIGN (decl);
1057 /* For user aligned vars or static vars align_variable already did
1058 everything. */
1059 if (DECL_USER_ALIGN (decl) || !TREE_PUBLIC (decl))
1060 return align;
1062 #ifdef DATA_ABI_ALIGNMENT
1063 if (DECL_THREAD_LOCAL_P (decl))
1064 align = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1065 #endif
1067 /* For decls that bind to the current definition, align_variable
1068 did also everything, except for not assuming ABI required alignment
1069 of TLS variables. For other vars, increase the alignment here
1070 as an optimization. */
1071 if (!decl_binds_to_current_def_p (decl))
1073 /* On some machines, it is good to increase alignment sometimes. */
1074 #ifdef DATA_ALIGNMENT
1075 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1076 /* Don't increase alignment too much for TLS variables - TLS space
1077 is too precious. */
1078 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1079 align = data_align;
1080 #endif
1081 #ifdef CONSTANT_ALIGNMENT
1082 if (DECL_INITIAL (decl) != 0
1083 /* In LTO we have no errors in program; error_mark_node is used
1084 to mark offlined constructors. */
1085 && (in_lto_p || DECL_INITIAL (decl) != error_mark_node))
1087 unsigned int const_align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl),
1088 align);
1089 /* Don't increase alignment too much for TLS variables - TLS space
1090 is too precious. */
1091 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1092 align = const_align;
1094 #endif
1097 return align;
1100 /* Return the section into which the given VAR_DECL or CONST_DECL
1101 should be placed. PREFER_NOSWITCH_P is true if a noswitch
1102 section should be used wherever possible. */
1104 section *
1105 get_variable_section (tree decl, bool prefer_noswitch_p)
1107 addr_space_t as = ADDR_SPACE_GENERIC;
1108 int reloc;
1109 varpool_node *vnode = varpool_node::get (decl);
1110 if (vnode)
1112 vnode = vnode->ultimate_alias_target ();
1113 decl = vnode->decl;
1116 if (TREE_TYPE (decl) != error_mark_node)
1117 as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1119 /* We need the constructor to figure out reloc flag. */
1120 if (vnode)
1121 vnode->get_constructor ();
1123 if (DECL_COMMON (decl))
1125 /* If the decl has been given an explicit section name, or it resides
1126 in a non-generic address space, then it isn't common, and shouldn't
1127 be handled as such. */
1128 gcc_assert (DECL_SECTION_NAME (decl) == NULL
1129 && ADDR_SPACE_GENERIC_P (as));
1130 if (DECL_THREAD_LOCAL_P (decl))
1131 return tls_comm_section;
1132 else if (TREE_PUBLIC (decl) && bss_initializer_p (decl))
1133 return comm_section;
1136 if (DECL_INITIAL (decl) == error_mark_node)
1137 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1138 else if (DECL_INITIAL (decl))
1139 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1140 else
1141 reloc = 0;
1143 resolve_unique_section (decl, reloc, flag_data_sections);
1144 if (IN_NAMED_SECTION (decl))
1145 return get_named_section (decl, NULL, reloc);
1147 if (ADDR_SPACE_GENERIC_P (as)
1148 && !DECL_THREAD_LOCAL_P (decl)
1149 && !(prefer_noswitch_p && targetm.have_switchable_bss_sections)
1150 && bss_initializer_p (decl))
1152 if (!TREE_PUBLIC (decl)
1153 && !((flag_sanitize & SANITIZE_ADDRESS)
1154 && asan_protect_global (decl)))
1155 return lcomm_section;
1156 if (bss_noswitch_section)
1157 return bss_noswitch_section;
1160 return targetm.asm_out.select_section (decl, reloc,
1161 get_variable_align (decl));
1164 /* Return the block into which object_block DECL should be placed. */
1166 static struct object_block *
1167 get_block_for_decl (tree decl)
1169 section *sect;
1171 if (TREE_CODE (decl) == VAR_DECL)
1173 /* The object must be defined in this translation unit. */
1174 if (DECL_EXTERNAL (decl))
1175 return NULL;
1177 /* There's no point using object blocks for something that is
1178 isolated by definition. */
1179 if (DECL_COMDAT_GROUP (decl))
1180 return NULL;
1183 /* We can only calculate block offsets if the decl has a known
1184 constant size. */
1185 if (DECL_SIZE_UNIT (decl) == NULL)
1186 return NULL;
1187 if (!tree_fits_uhwi_p (DECL_SIZE_UNIT (decl)))
1188 return NULL;
1190 /* Find out which section should contain DECL. We cannot put it into
1191 an object block if it requires a standalone definition. */
1192 if (TREE_CODE (decl) == VAR_DECL)
1193 align_variable (decl, 0);
1194 sect = get_variable_section (decl, true);
1195 if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
1196 return NULL;
1198 return get_block_for_section (sect);
1201 /* Make sure block symbol SYMBOL is in block BLOCK. */
1203 static void
1204 change_symbol_block (rtx symbol, struct object_block *block)
1206 if (block != SYMBOL_REF_BLOCK (symbol))
1208 gcc_assert (SYMBOL_REF_BLOCK_OFFSET (symbol) < 0);
1209 SYMBOL_REF_BLOCK (symbol) = block;
1213 /* Return true if it is possible to put DECL in an object_block. */
1215 static bool
1216 use_blocks_for_decl_p (tree decl)
1218 struct symtab_node *snode;
1220 /* Only data DECLs can be placed into object blocks. */
1221 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != CONST_DECL)
1222 return false;
1224 /* Detect decls created by dw2_force_const_mem. Such decls are
1225 special because DECL_INITIAL doesn't specify the decl's true value.
1226 dw2_output_indirect_constants will instead call assemble_variable
1227 with dont_output_data set to 1 and then print the contents itself. */
1228 if (DECL_INITIAL (decl) == decl)
1229 return false;
1231 /* If this decl is an alias, then we don't want to emit a
1232 definition. */
1233 if (TREE_CODE (decl) == VAR_DECL
1234 && (snode = symtab_node::get (decl)) != NULL
1235 && snode->alias)
1236 return false;
1238 return targetm.use_blocks_for_decl_p (decl);
1241 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
1242 have static storage duration. In other words, it should not be an
1243 automatic variable, including PARM_DECLs.
1245 There is, however, one exception: this function handles variables
1246 explicitly placed in a particular register by the user.
1248 This is never called for PARM_DECL nodes. */
1250 void
1251 make_decl_rtl (tree decl)
1253 const char *name = 0;
1254 int reg_number;
1255 rtx x;
1257 /* Check that we are not being given an automatic variable. */
1258 gcc_assert (TREE_CODE (decl) != PARM_DECL
1259 && TREE_CODE (decl) != RESULT_DECL);
1261 /* A weak alias has TREE_PUBLIC set but not the other bits. */
1262 gcc_assert (TREE_CODE (decl) != VAR_DECL
1263 || TREE_STATIC (decl)
1264 || TREE_PUBLIC (decl)
1265 || DECL_EXTERNAL (decl)
1266 || DECL_REGISTER (decl));
1268 /* And that we were not given a type or a label. */
1269 gcc_assert (TREE_CODE (decl) != TYPE_DECL
1270 && TREE_CODE (decl) != LABEL_DECL);
1272 /* For a duplicate declaration, we can be called twice on the
1273 same DECL node. Don't discard the RTL already made. */
1274 if (DECL_RTL_SET_P (decl))
1276 /* If the old RTL had the wrong mode, fix the mode. */
1277 x = DECL_RTL (decl);
1278 if (GET_MODE (x) != DECL_MODE (decl))
1279 SET_DECL_RTL (decl, adjust_address_nv (x, DECL_MODE (decl), 0));
1281 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1282 return;
1284 /* ??? Another way to do this would be to maintain a hashed
1285 table of such critters. Instead of adding stuff to a DECL
1286 to give certain attributes to it, we could use an external
1287 hash map from DECL to set of attributes. */
1289 /* Let the target reassign the RTL if it wants.
1290 This is necessary, for example, when one machine specific
1291 decl attribute overrides another. */
1292 targetm.encode_section_info (decl, DECL_RTL (decl), false);
1294 /* If the symbol has a SYMBOL_REF_BLOCK field, update it based
1295 on the new decl information. */
1296 if (MEM_P (x)
1297 && GET_CODE (XEXP (x, 0)) == SYMBOL_REF
1298 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (x, 0)))
1299 change_symbol_block (XEXP (x, 0), get_block_for_decl (decl));
1301 return;
1304 /* If this variable belongs to the global constant pool, retrieve the
1305 pre-computed RTL or recompute it in LTO mode. */
1306 if (TREE_CODE (decl) == VAR_DECL && DECL_IN_CONSTANT_POOL (decl))
1308 SET_DECL_RTL (decl, output_constant_def (DECL_INITIAL (decl), 1));
1309 return;
1312 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
1314 if (name[0] != '*' && TREE_CODE (decl) != FUNCTION_DECL
1315 && DECL_REGISTER (decl))
1317 error ("register name not specified for %q+D", decl);
1319 else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1321 const char *asmspec = name+1;
1322 enum machine_mode mode = DECL_MODE (decl);
1323 reg_number = decode_reg_name (asmspec);
1324 /* First detect errors in declaring global registers. */
1325 if (reg_number == -1)
1326 error ("register name not specified for %q+D", decl);
1327 else if (reg_number < 0)
1328 error ("invalid register name for %q+D", decl);
1329 else if (mode == BLKmode)
1330 error ("data type of %q+D isn%'t suitable for a register",
1331 decl);
1332 else if (!in_hard_reg_set_p (accessible_reg_set, mode, reg_number))
1333 error ("the register specified for %q+D cannot be accessed"
1334 " by the current target", decl);
1335 else if (!in_hard_reg_set_p (operand_reg_set, mode, reg_number))
1336 error ("the register specified for %q+D is not general enough"
1337 " to be used as a register variable", decl);
1338 else if (!HARD_REGNO_MODE_OK (reg_number, mode))
1339 error ("register specified for %q+D isn%'t suitable for data type",
1340 decl);
1341 /* Now handle properly declared static register variables. */
1342 else
1344 int nregs;
1346 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
1348 DECL_INITIAL (decl) = 0;
1349 error ("global register variable has initial value");
1351 if (TREE_THIS_VOLATILE (decl))
1352 warning (OPT_Wvolatile_register_var,
1353 "optimization may eliminate reads and/or "
1354 "writes to register variables");
1356 /* If the user specified one of the eliminables registers here,
1357 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
1358 confused with that register and be eliminated. This usage is
1359 somewhat suspect... */
1361 SET_DECL_RTL (decl, gen_rtx_raw_REG (mode, reg_number));
1362 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
1363 REG_USERVAR_P (DECL_RTL (decl)) = 1;
1365 if (TREE_STATIC (decl))
1367 /* Make this register global, so not usable for anything
1368 else. */
1369 #ifdef ASM_DECLARE_REGISTER_GLOBAL
1370 name = IDENTIFIER_POINTER (DECL_NAME (decl));
1371 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
1372 #endif
1373 nregs = hard_regno_nregs[reg_number][mode];
1374 while (nregs > 0)
1375 globalize_reg (decl, reg_number + --nregs);
1378 /* As a register variable, it has no section. */
1379 return;
1381 /* Avoid internal errors from invalid register
1382 specifications. */
1383 SET_DECL_ASSEMBLER_NAME (decl, NULL_TREE);
1384 DECL_HARD_REGISTER (decl) = 0;
1385 return;
1387 /* Now handle ordinary static variables and functions (in memory).
1388 Also handle vars declared register invalidly. */
1389 else if (name[0] == '*')
1391 #ifdef REGISTER_PREFIX
1392 if (strlen (REGISTER_PREFIX) != 0)
1394 reg_number = decode_reg_name (name);
1395 if (reg_number >= 0 || reg_number == -3)
1396 error ("register name given for non-register variable %q+D", decl);
1398 #endif
1401 /* Specifying a section attribute on a variable forces it into a
1402 non-.bss section, and thus it cannot be common. */
1403 /* FIXME: In general this code should not be necessary because
1404 visibility pass is doing the same work. But notice_global_symbol
1405 is called early and it needs to make DECL_RTL to get the name.
1406 we take care of recomputing the DECL_RTL after visibility is changed. */
1407 if (TREE_CODE (decl) == VAR_DECL
1408 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl))
1409 && DECL_SECTION_NAME (decl) != NULL
1410 && DECL_INITIAL (decl) == NULL_TREE
1411 && DECL_COMMON (decl))
1412 DECL_COMMON (decl) = 0;
1414 /* Variables can't be both common and weak. */
1415 if (TREE_CODE (decl) == VAR_DECL && DECL_WEAK (decl))
1416 DECL_COMMON (decl) = 0;
1418 if (use_object_blocks_p () && use_blocks_for_decl_p (decl))
1419 x = create_block_symbol (name, get_block_for_decl (decl), -1);
1420 else
1422 enum machine_mode address_mode = Pmode;
1423 if (TREE_TYPE (decl) != error_mark_node)
1425 addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1426 address_mode = targetm.addr_space.address_mode (as);
1428 x = gen_rtx_SYMBOL_REF (address_mode, name);
1430 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
1431 SET_SYMBOL_REF_DECL (x, decl);
1433 x = gen_rtx_MEM (DECL_MODE (decl), x);
1434 if (TREE_CODE (decl) != FUNCTION_DECL)
1435 set_mem_attributes (x, decl, 1);
1436 SET_DECL_RTL (decl, x);
1438 /* Optionally set flags or add text to the name to record information
1439 such as that it is a function name.
1440 If the name is changed, the macro ASM_OUTPUT_LABELREF
1441 will have to know how to strip this information. */
1442 targetm.encode_section_info (decl, DECL_RTL (decl), true);
1445 /* Like make_decl_rtl, but inhibit creation of new alias sets when
1446 calling make_decl_rtl. Also, reset DECL_RTL before returning the
1447 rtl. */
1450 make_decl_rtl_for_debug (tree decl)
1452 unsigned int save_aliasing_flag;
1453 rtx rtl;
1455 if (DECL_RTL_SET_P (decl))
1456 return DECL_RTL (decl);
1458 /* Kludge alert! Somewhere down the call chain, make_decl_rtl will
1459 call new_alias_set. If running with -fcompare-debug, sometimes
1460 we do not want to create alias sets that will throw the alias
1461 numbers off in the comparison dumps. So... clearing
1462 flag_strict_aliasing will keep new_alias_set() from creating a
1463 new set. */
1464 save_aliasing_flag = flag_strict_aliasing;
1465 flag_strict_aliasing = 0;
1467 rtl = DECL_RTL (decl);
1468 /* Reset DECL_RTL back, as various parts of the compiler expects
1469 DECL_RTL set meaning it is actually going to be output. */
1470 SET_DECL_RTL (decl, NULL);
1472 flag_strict_aliasing = save_aliasing_flag;
1473 return rtl;
1476 /* Output a string of literal assembler code
1477 for an `asm' keyword used between functions. */
1479 void
1480 assemble_asm (tree string)
1482 const char *p;
1483 app_enable ();
1485 if (TREE_CODE (string) == ADDR_EXPR)
1486 string = TREE_OPERAND (string, 0);
1488 p = TREE_STRING_POINTER (string);
1489 fprintf (asm_out_file, "%s%s\n", p[0] == '\t' ? "" : "\t", p);
1492 /* Write the address of the entity given by SYMBOL to SEC. */
1493 void
1494 assemble_addr_to_section (rtx symbol, section *sec)
1496 switch_to_section (sec);
1497 assemble_align (POINTER_SIZE);
1498 assemble_integer (symbol, POINTER_SIZE_UNITS, POINTER_SIZE, 1);
1501 /* Return the numbered .ctors.N (if CONSTRUCTOR_P) or .dtors.N (if
1502 not) section for PRIORITY. */
1503 section *
1504 get_cdtor_priority_section (int priority, bool constructor_p)
1506 char buf[16];
1508 /* ??? This only works reliably with the GNU linker. */
1509 sprintf (buf, "%s.%.5u",
1510 constructor_p ? ".ctors" : ".dtors",
1511 /* Invert the numbering so the linker puts us in the proper
1512 order; constructors are run from right to left, and the
1513 linker sorts in increasing order. */
1514 MAX_INIT_PRIORITY - priority);
1515 return get_section (buf, SECTION_WRITE, NULL);
1518 void
1519 default_named_section_asm_out_destructor (rtx symbol, int priority)
1521 section *sec;
1523 if (priority != DEFAULT_INIT_PRIORITY)
1524 sec = get_cdtor_priority_section (priority,
1525 /*constructor_p=*/false);
1526 else
1527 sec = get_section (".dtors", SECTION_WRITE, NULL);
1529 assemble_addr_to_section (symbol, sec);
1532 #ifdef DTORS_SECTION_ASM_OP
1533 void
1534 default_dtor_section_asm_out_destructor (rtx symbol,
1535 int priority ATTRIBUTE_UNUSED)
1537 assemble_addr_to_section (symbol, dtors_section);
1539 #endif
1541 void
1542 default_named_section_asm_out_constructor (rtx symbol, int priority)
1544 section *sec;
1546 if (priority != DEFAULT_INIT_PRIORITY)
1547 sec = get_cdtor_priority_section (priority,
1548 /*constructor_p=*/true);
1549 else
1550 sec = get_section (".ctors", SECTION_WRITE, NULL);
1552 assemble_addr_to_section (symbol, sec);
1555 #ifdef CTORS_SECTION_ASM_OP
1556 void
1557 default_ctor_section_asm_out_constructor (rtx symbol,
1558 int priority ATTRIBUTE_UNUSED)
1560 assemble_addr_to_section (symbol, ctors_section);
1562 #endif
1564 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1565 a nonzero value if the constant pool should be output before the
1566 start of the function, or a zero value if the pool should output
1567 after the end of the function. The default is to put it before the
1568 start. */
1570 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1571 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1572 #endif
1574 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1575 to be output to assembler.
1576 Set first_global_object_name and weak_global_object_name as appropriate. */
1578 void
1579 notice_global_symbol (tree decl)
1581 const char **type = &first_global_object_name;
1583 if (first_global_object_name
1584 || !TREE_PUBLIC (decl)
1585 || DECL_EXTERNAL (decl)
1586 || !DECL_NAME (decl)
1587 || (TREE_CODE (decl) != FUNCTION_DECL
1588 && (TREE_CODE (decl) != VAR_DECL
1589 || (DECL_COMMON (decl)
1590 && (DECL_INITIAL (decl) == 0
1591 || DECL_INITIAL (decl) == error_mark_node))))
1592 || !MEM_P (DECL_RTL (decl)))
1593 return;
1595 /* We win when global object is found, but it is useful to know about weak
1596 symbol as well so we can produce nicer unique names. */
1597 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl) || flag_shlib)
1598 type = &weak_global_object_name;
1600 if (!*type)
1602 const char *p;
1603 const char *name;
1604 rtx decl_rtl = DECL_RTL (decl);
1606 p = targetm.strip_name_encoding (XSTR (XEXP (decl_rtl, 0), 0));
1607 name = ggc_strdup (p);
1609 *type = name;
1613 /* If not using flag_reorder_blocks_and_partition, decide early whether the
1614 current function goes into the cold section, so that targets can use
1615 current_function_section during RTL expansion. DECL describes the
1616 function. */
1618 void
1619 decide_function_section (tree decl)
1621 first_function_block_is_cold = false;
1623 if (flag_reorder_blocks_and_partition)
1624 /* We will decide in assemble_start_function. */
1625 return;
1627 if (DECL_SECTION_NAME (decl))
1629 struct cgraph_node *node = cgraph_node::get (current_function_decl);
1630 /* Calls to function_section rely on first_function_block_is_cold
1631 being accurate. */
1632 first_function_block_is_cold = (node
1633 && node->frequency
1634 == NODE_FREQUENCY_UNLIKELY_EXECUTED);
1637 in_cold_section_p = first_function_block_is_cold;
1640 /* Output assembler code for the constant pool of a function and associated
1641 with defining the name of the function. DECL describes the function.
1642 NAME is the function's name. For the constant pool, we use the current
1643 constant pool data. */
1645 void
1646 assemble_start_function (tree decl, const char *fnname)
1648 int align;
1649 char tmp_label[100];
1650 bool hot_label_written = false;
1652 if (flag_reorder_blocks_and_partition)
1654 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTB", const_labelno);
1655 crtl->subsections.hot_section_label = ggc_strdup (tmp_label);
1656 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDB", const_labelno);
1657 crtl->subsections.cold_section_label = ggc_strdup (tmp_label);
1658 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTE", const_labelno);
1659 crtl->subsections.hot_section_end_label = ggc_strdup (tmp_label);
1660 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDE", const_labelno);
1661 crtl->subsections.cold_section_end_label = ggc_strdup (tmp_label);
1662 const_labelno++;
1664 else
1666 crtl->subsections.hot_section_label = NULL;
1667 crtl->subsections.cold_section_label = NULL;
1668 crtl->subsections.hot_section_end_label = NULL;
1669 crtl->subsections.cold_section_end_label = NULL;
1672 /* The following code does not need preprocessing in the assembler. */
1674 app_disable ();
1676 if (CONSTANT_POOL_BEFORE_FUNCTION)
1677 output_constant_pool (fnname, decl);
1679 /* Make sure the not and cold text (code) sections are properly
1680 aligned. This is necessary here in the case where the function
1681 has both hot and cold sections, because we don't want to re-set
1682 the alignment when the section switch happens mid-function. */
1684 if (flag_reorder_blocks_and_partition)
1686 first_function_block_is_cold = false;
1688 switch_to_section (unlikely_text_section ());
1689 assemble_align (DECL_ALIGN (decl));
1690 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_label);
1692 /* When the function starts with a cold section, we need to explicitly
1693 align the hot section and write out the hot section label.
1694 But if the current function is a thunk, we do not have a CFG. */
1695 if (!cfun->is_thunk
1696 && BB_PARTITION (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) == BB_COLD_PARTITION)
1698 switch_to_section (text_section);
1699 assemble_align (DECL_ALIGN (decl));
1700 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1701 hot_label_written = true;
1702 first_function_block_is_cold = true;
1704 in_cold_section_p = first_function_block_is_cold;
1708 /* Switch to the correct text section for the start of the function. */
1710 switch_to_section (function_section (decl));
1711 if (flag_reorder_blocks_and_partition
1712 && !hot_label_written)
1713 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1715 /* Tell assembler to move to target machine's alignment for functions. */
1716 align = floor_log2 (DECL_ALIGN (decl) / BITS_PER_UNIT);
1717 if (align > 0)
1719 ASM_OUTPUT_ALIGN (asm_out_file, align);
1722 /* Handle a user-specified function alignment.
1723 Note that we still need to align to DECL_ALIGN, as above,
1724 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1725 if (! DECL_USER_ALIGN (decl)
1726 && align_functions_log > align
1727 && optimize_function_for_speed_p (cfun))
1729 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1730 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1731 align_functions_log, align_functions - 1);
1732 #else
1733 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1734 #endif
1737 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1738 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1739 #endif
1741 if (!DECL_IGNORED_P (decl))
1742 (*debug_hooks->begin_function) (decl);
1744 /* Make function name accessible from other files, if appropriate. */
1746 if (TREE_PUBLIC (decl))
1748 notice_global_symbol (decl);
1750 globalize_decl (decl);
1752 maybe_assemble_visibility (decl);
1755 if (DECL_PRESERVE_P (decl))
1756 targetm.asm_out.mark_decl_preserved (fnname);
1758 /* Do any machine/system dependent processing of the function name. */
1759 #ifdef ASM_DECLARE_FUNCTION_NAME
1760 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1761 #else
1762 /* Standard thing is just output label for the function. */
1763 ASM_OUTPUT_FUNCTION_LABEL (asm_out_file, fnname, current_function_decl);
1764 #endif /* ASM_DECLARE_FUNCTION_NAME */
1766 if (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (decl)))
1767 saw_no_split_stack = true;
1770 /* Output assembler code associated with defining the size of the
1771 function. DECL describes the function. NAME is the function's name. */
1773 void
1774 assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED)
1776 #ifdef ASM_DECLARE_FUNCTION_SIZE
1777 /* We could have switched section in the middle of the function. */
1778 if (flag_reorder_blocks_and_partition)
1779 switch_to_section (function_section (decl));
1780 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1781 #endif
1782 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1784 output_constant_pool (fnname, decl);
1785 switch_to_section (function_section (decl)); /* need to switch back */
1787 /* Output labels for end of hot/cold text sections (to be used by
1788 debug info.) */
1789 if (flag_reorder_blocks_and_partition)
1791 section *save_text_section;
1793 save_text_section = in_section;
1794 switch_to_section (unlikely_text_section ());
1795 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label);
1796 if (first_function_block_is_cold)
1797 switch_to_section (text_section);
1798 else
1799 switch_to_section (function_section (decl));
1800 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label);
1801 switch_to_section (save_text_section);
1805 /* Assemble code to leave SIZE bytes of zeros. */
1807 void
1808 assemble_zeros (unsigned HOST_WIDE_INT size)
1810 /* Do no output if -fsyntax-only. */
1811 if (flag_syntax_only)
1812 return;
1814 #ifdef ASM_NO_SKIP_IN_TEXT
1815 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1816 so we must output 0s explicitly in the text section. */
1817 if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0)
1819 unsigned HOST_WIDE_INT i;
1820 for (i = 0; i < size; i++)
1821 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1823 else
1824 #endif
1825 if (size > 0)
1826 ASM_OUTPUT_SKIP (asm_out_file, size);
1829 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1831 void
1832 assemble_align (int align)
1834 if (align > BITS_PER_UNIT)
1836 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1840 /* Assemble a string constant with the specified C string as contents. */
1842 void
1843 assemble_string (const char *p, int size)
1845 int pos = 0;
1846 int maximum = 2000;
1848 /* If the string is very long, split it up. */
1850 while (pos < size)
1852 int thissize = size - pos;
1853 if (thissize > maximum)
1854 thissize = maximum;
1856 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1858 pos += thissize;
1859 p += thissize;
1864 /* A noswitch_section_callback for lcomm_section. */
1866 static bool
1867 emit_local (tree decl ATTRIBUTE_UNUSED,
1868 const char *name ATTRIBUTE_UNUSED,
1869 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1870 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1872 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1873 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name,
1874 size, DECL_ALIGN (decl));
1875 return true;
1876 #elif defined ASM_OUTPUT_ALIGNED_LOCAL
1877 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, DECL_ALIGN (decl));
1878 return true;
1879 #else
1880 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1881 return false;
1882 #endif
1885 /* A noswitch_section_callback for bss_noswitch_section. */
1887 #if defined ASM_OUTPUT_ALIGNED_BSS
1888 static bool
1889 emit_bss (tree decl ATTRIBUTE_UNUSED,
1890 const char *name ATTRIBUTE_UNUSED,
1891 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1892 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1894 #if defined ASM_OUTPUT_ALIGNED_BSS
1895 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size,
1896 get_variable_align (decl));
1897 return true;
1898 #endif
1900 #endif
1902 /* A noswitch_section_callback for comm_section. */
1904 static bool
1905 emit_common (tree decl ATTRIBUTE_UNUSED,
1906 const char *name ATTRIBUTE_UNUSED,
1907 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1908 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1910 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1911 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name,
1912 size, get_variable_align (decl));
1913 return true;
1914 #elif defined ASM_OUTPUT_ALIGNED_COMMON
1915 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size,
1916 get_variable_align (decl));
1917 return true;
1918 #else
1919 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
1920 return false;
1921 #endif
1924 /* A noswitch_section_callback for tls_comm_section. */
1926 static bool
1927 emit_tls_common (tree decl ATTRIBUTE_UNUSED,
1928 const char *name ATTRIBUTE_UNUSED,
1929 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1930 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1932 #ifdef ASM_OUTPUT_TLS_COMMON
1933 ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size);
1934 return true;
1935 #else
1936 sorry ("thread-local COMMON data not implemented");
1937 return true;
1938 #endif
1941 /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT.
1942 NAME is the name of DECL's SYMBOL_REF. */
1944 static void
1945 assemble_noswitch_variable (tree decl, const char *name, section *sect,
1946 unsigned int align)
1948 unsigned HOST_WIDE_INT size, rounded;
1950 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
1951 rounded = size;
1953 if ((flag_sanitize & SANITIZE_ADDRESS) && asan_protect_global (decl))
1954 size += asan_red_zone_size (size);
1956 /* Don't allocate zero bytes of common,
1957 since that means "undefined external" in the linker. */
1958 if (size == 0)
1959 rounded = 1;
1961 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1962 so that each uninitialized object starts on such a boundary. */
1963 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
1964 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1965 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1967 if (!sect->noswitch.callback (decl, name, size, rounded)
1968 && (unsigned HOST_WIDE_INT) (align / BITS_PER_UNIT) > rounded)
1969 error ("requested alignment for %q+D is greater than "
1970 "implemented alignment of %wu", decl, rounded);
1973 /* A subroutine of assemble_variable. Output the label and contents of
1974 DECL, whose address is a SYMBOL_REF with name NAME. DONT_OUTPUT_DATA
1975 is as for assemble_variable. */
1977 static void
1978 assemble_variable_contents (tree decl, const char *name,
1979 bool dont_output_data)
1981 /* Do any machine/system dependent processing of the object. */
1982 #ifdef ASM_DECLARE_OBJECT_NAME
1983 last_assemble_variable_decl = decl;
1984 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
1985 #else
1986 /* Standard thing is just output label for the object. */
1987 ASM_OUTPUT_LABEL (asm_out_file, name);
1988 #endif /* ASM_DECLARE_OBJECT_NAME */
1990 if (!dont_output_data)
1992 /* Caller is supposed to use varpool_get_constructor when it wants
1993 to output the body. */
1994 gcc_assert (!in_lto_p || DECL_INITIAL (decl) != error_mark_node);
1995 if (DECL_INITIAL (decl)
1996 && DECL_INITIAL (decl) != error_mark_node
1997 && !initializer_zerop (DECL_INITIAL (decl)))
1998 /* Output the actual data. */
1999 output_constant (DECL_INITIAL (decl),
2000 tree_to_uhwi (DECL_SIZE_UNIT (decl)),
2001 get_variable_align (decl));
2002 else
2003 /* Leave space for it. */
2004 assemble_zeros (tree_to_uhwi (DECL_SIZE_UNIT (decl)));
2008 /* Assemble everything that is needed for a variable or function declaration.
2009 Not used for automatic variables, and not used for function definitions.
2010 Should not be called for variables of incomplete structure type.
2012 TOP_LEVEL is nonzero if this variable has file scope.
2013 AT_END is nonzero if this is the special handling, at end of compilation,
2014 to define things that have had only tentative definitions.
2015 DONT_OUTPUT_DATA if nonzero means don't actually output the
2016 initial value (that will be done by the caller). */
2018 void
2019 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
2020 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
2022 const char *name;
2023 rtx decl_rtl, symbol;
2024 section *sect;
2025 unsigned int align;
2026 bool asan_protected = false;
2028 /* This function is supposed to handle VARIABLES. Ensure we have one. */
2029 gcc_assert (TREE_CODE (decl) == VAR_DECL);
2031 /* Emulated TLS had better not get this far. */
2032 gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl));
2034 last_assemble_variable_decl = 0;
2036 /* Normally no need to say anything here for external references,
2037 since assemble_external is called by the language-specific code
2038 when a declaration is first seen. */
2040 if (DECL_EXTERNAL (decl))
2041 return;
2043 /* Do nothing for global register variables. */
2044 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
2046 TREE_ASM_WRITTEN (decl) = 1;
2047 return;
2050 /* If type was incomplete when the variable was declared,
2051 see if it is complete now. */
2053 if (DECL_SIZE (decl) == 0)
2054 layout_decl (decl, 0);
2056 /* Still incomplete => don't allocate it; treat the tentative defn
2057 (which is what it must have been) as an `extern' reference. */
2059 if (!dont_output_data && DECL_SIZE (decl) == 0)
2061 error ("storage size of %q+D isn%'t known", decl);
2062 TREE_ASM_WRITTEN (decl) = 1;
2063 return;
2066 /* The first declaration of a variable that comes through this function
2067 decides whether it is global (in C, has external linkage)
2068 or local (in C, has internal linkage). So do nothing more
2069 if this function has already run. */
2071 if (TREE_ASM_WRITTEN (decl))
2072 return;
2074 /* Make sure targetm.encode_section_info is invoked before we set
2075 ASM_WRITTEN. */
2076 decl_rtl = DECL_RTL (decl);
2078 TREE_ASM_WRITTEN (decl) = 1;
2080 /* Do no output if -fsyntax-only. */
2081 if (flag_syntax_only)
2082 return;
2084 if (! dont_output_data
2085 && ! valid_constant_size_p (DECL_SIZE_UNIT (decl)))
2087 error ("size of variable %q+D is too large", decl);
2088 return;
2091 gcc_assert (MEM_P (decl_rtl));
2092 gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF);
2093 symbol = XEXP (decl_rtl, 0);
2095 /* If this symbol belongs to the tree constant pool, output the constant
2096 if it hasn't already been written. */
2097 if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
2099 tree decl = SYMBOL_REF_DECL (symbol);
2100 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
2101 output_constant_def_contents (symbol);
2102 return;
2105 app_disable ();
2107 name = XSTR (symbol, 0);
2108 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
2109 notice_global_symbol (decl);
2111 /* Compute the alignment of this data. */
2113 align_variable (decl, dont_output_data);
2115 if ((flag_sanitize & SANITIZE_ADDRESS)
2116 && asan_protect_global (decl))
2118 asan_protected = true;
2119 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
2120 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
2123 set_mem_align (decl_rtl, DECL_ALIGN (decl));
2125 align = get_variable_align (decl);
2127 if (TREE_PUBLIC (decl))
2128 maybe_assemble_visibility (decl);
2130 if (DECL_PRESERVE_P (decl))
2131 targetm.asm_out.mark_decl_preserved (name);
2133 /* First make the assembler name(s) global if appropriate. */
2134 sect = get_variable_section (decl, false);
2135 if (TREE_PUBLIC (decl)
2136 && (sect->common.flags & SECTION_COMMON) == 0)
2137 globalize_decl (decl);
2139 /* Output any data that we will need to use the address of. */
2140 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
2141 output_addressed_constants (DECL_INITIAL (decl));
2143 /* dbxout.c needs to know this. */
2144 if (sect && (sect->common.flags & SECTION_CODE) != 0)
2145 DECL_IN_TEXT_SECTION (decl) = 1;
2147 /* If the decl is part of an object_block, make sure that the decl
2148 has been positioned within its block, but do not write out its
2149 definition yet. output_object_blocks will do that later. */
2150 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
2152 gcc_assert (!dont_output_data);
2153 place_block_symbol (symbol);
2155 else if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
2156 assemble_noswitch_variable (decl, name, sect, align);
2157 else
2159 /* The following bit of code ensures that vtable_map
2160 variables are not only in the comdat section, but that
2161 each variable has its own unique comdat name. If this
2162 code is removed, the variables end up in the same section
2163 with a single comdat name.
2165 FIXME: resolve_unique_section needs to deal better with
2166 decls with both DECL_SECTION_NAME and DECL_ONE_ONLY. Once
2167 that is fixed, this if-else statement can be replaced with
2168 a single call to "switch_to_section (sect)". */
2169 if (sect->named.name
2170 && (strcmp (sect->named.name, ".vtable_map_vars") == 0))
2172 #if defined (OBJECT_FORMAT_ELF)
2173 targetm.asm_out.named_section (sect->named.name,
2174 sect->named.common.flags
2175 | SECTION_LINKONCE,
2176 DECL_NAME (decl));
2177 in_section = sect;
2178 #else
2179 switch_to_section (sect);
2180 #endif
2182 else
2183 switch_to_section (sect);
2184 if (align > BITS_PER_UNIT)
2185 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2186 assemble_variable_contents (decl, name, dont_output_data);
2187 if (asan_protected)
2189 unsigned HOST_WIDE_INT int size
2190 = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2191 assemble_zeros (asan_red_zone_size (size));
2197 /* Given a function declaration (FN_DECL), this function assembles the
2198 function into the .preinit_array section. */
2200 void
2201 assemble_vtv_preinit_initializer (tree fn_decl)
2203 section *sect;
2204 unsigned flags = SECTION_WRITE;
2205 rtx symbol = XEXP (DECL_RTL (fn_decl), 0);
2207 flags |= SECTION_NOTYPE;
2208 sect = get_section (".preinit_array", flags, fn_decl);
2209 switch_to_section (sect);
2210 assemble_addr_to_section (symbol, sect);
2213 /* Return 1 if type TYPE contains any pointers. */
2215 static int
2216 contains_pointers_p (tree type)
2218 switch (TREE_CODE (type))
2220 case POINTER_TYPE:
2221 case REFERENCE_TYPE:
2222 /* I'm not sure whether OFFSET_TYPE needs this treatment,
2223 so I'll play safe and return 1. */
2224 case OFFSET_TYPE:
2225 return 1;
2227 case RECORD_TYPE:
2228 case UNION_TYPE:
2229 case QUAL_UNION_TYPE:
2231 tree fields;
2232 /* For a type that has fields, see if the fields have pointers. */
2233 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2234 if (TREE_CODE (fields) == FIELD_DECL
2235 && contains_pointers_p (TREE_TYPE (fields)))
2236 return 1;
2237 return 0;
2240 case ARRAY_TYPE:
2241 /* An array type contains pointers if its element type does. */
2242 return contains_pointers_p (TREE_TYPE (type));
2244 default:
2245 return 0;
2249 /* We delay assemble_external processing until
2250 the compilation unit is finalized. This is the best we can do for
2251 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2252 it all the way to final. See PR 17982 for further discussion. */
2253 static GTY(()) tree pending_assemble_externals;
2255 #ifdef ASM_OUTPUT_EXTERNAL
2256 /* Some targets delay some output to final using TARGET_ASM_FILE_END.
2257 As a result, assemble_external can be called after the list of externals
2258 is processed and the pointer set destroyed. */
2259 static bool pending_assemble_externals_processed;
2261 /* Avoid O(external_decls**2) lookups in the pending_assemble_externals
2262 TREE_LIST in assemble_external. */
2263 static hash_set<tree> *pending_assemble_externals_set;
2265 /* True if DECL is a function decl for which no out-of-line copy exists.
2266 It is assumed that DECL's assembler name has been set. */
2268 static bool
2269 incorporeal_function_p (tree decl)
2271 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
2273 const char *name;
2275 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2276 && (DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA
2277 || DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA_WITH_ALIGN))
2278 return true;
2280 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2281 /* Atomic or sync builtins which have survived this far will be
2282 resolved externally and therefore are not incorporeal. */
2283 if (strncmp (name, "__builtin_", 10) == 0)
2284 return true;
2286 return false;
2289 /* Actually do the tests to determine if this is necessary, and invoke
2290 ASM_OUTPUT_EXTERNAL. */
2291 static void
2292 assemble_external_real (tree decl)
2294 rtx rtl = DECL_RTL (decl);
2296 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2297 && !SYMBOL_REF_USED (XEXP (rtl, 0))
2298 && !incorporeal_function_p (decl))
2300 /* Some systems do require some output. */
2301 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2302 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2305 #endif
2307 void
2308 process_pending_assemble_externals (void)
2310 #ifdef ASM_OUTPUT_EXTERNAL
2311 tree list;
2312 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2313 assemble_external_real (TREE_VALUE (list));
2315 pending_assemble_externals = 0;
2316 pending_assemble_externals_processed = true;
2317 delete pending_assemble_externals_set;
2318 #endif
2321 /* This TREE_LIST contains any weak symbol declarations waiting
2322 to be emitted. */
2323 static GTY(()) tree weak_decls;
2325 /* Output something to declare an external symbol to the assembler,
2326 and qualifiers such as weakness. (Most assemblers don't need
2327 extern declaration, so we normally output nothing.) Do nothing if
2328 DECL is not external. */
2330 void
2331 assemble_external (tree decl ATTRIBUTE_UNUSED)
2333 /* Make sure that the ASM_OUT_FILE is open.
2334 If it's not, we should not be calling this function. */
2335 gcc_assert (asm_out_file);
2337 /* In a perfect world, the following condition would be true.
2338 Sadly, the Java and Go front ends emit assembly *from the front end*,
2339 bypassing the call graph. See PR52739. Fix before GCC 4.8. */
2340 #if 0
2341 /* This function should only be called if we are expanding, or have
2342 expanded, to RTL.
2343 Ideally, only final.c would be calling this function, but it is
2344 not clear whether that would break things somehow. See PR 17982
2345 for further discussion. */
2346 gcc_assert (state == EXPANSION
2347 || state == FINISHED);
2348 #endif
2350 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2351 return;
2353 /* We want to output annotation for weak and external symbols at
2354 very last to check if they are references or not. */
2356 if (TARGET_SUPPORTS_WEAK
2357 && DECL_WEAK (decl)
2358 /* TREE_STATIC is a weird and abused creature which is not
2359 generally the right test for whether an entity has been
2360 locally emitted, inlined or otherwise not-really-extern, but
2361 for declarations that can be weak, it happens to be
2362 match. */
2363 && !TREE_STATIC (decl)
2364 && lookup_attribute ("weak", DECL_ATTRIBUTES (decl))
2365 && value_member (decl, weak_decls) == NULL_TREE)
2366 weak_decls = tree_cons (NULL, decl, weak_decls);
2368 #ifdef ASM_OUTPUT_EXTERNAL
2369 if (pending_assemble_externals_processed)
2371 assemble_external_real (decl);
2372 return;
2375 if (! pending_assemble_externals_set->add (decl))
2376 pending_assemble_externals = tree_cons (NULL, decl,
2377 pending_assemble_externals);
2378 #endif
2381 /* Similar, for calling a library function FUN. */
2383 void
2384 assemble_external_libcall (rtx fun)
2386 /* Declare library function name external when first used, if nec. */
2387 if (! SYMBOL_REF_USED (fun))
2389 SYMBOL_REF_USED (fun) = 1;
2390 targetm.asm_out.external_libcall (fun);
2394 /* Assemble a label named NAME. */
2396 void
2397 assemble_label (FILE *file, const char *name)
2399 ASM_OUTPUT_LABEL (file, name);
2402 /* Set the symbol_referenced flag for ID. */
2403 void
2404 mark_referenced (tree id)
2406 TREE_SYMBOL_REFERENCED (id) = 1;
2409 /* Set the symbol_referenced flag for DECL and notify callgraph. */
2410 void
2411 mark_decl_referenced (tree decl)
2413 if (TREE_CODE (decl) == FUNCTION_DECL)
2415 /* Extern inline functions don't become needed when referenced.
2416 If we know a method will be emitted in other TU and no new
2417 functions can be marked reachable, just use the external
2418 definition. */
2419 struct cgraph_node *node = cgraph_node::get_create (decl);
2420 if (!DECL_EXTERNAL (decl)
2421 && !node->definition)
2422 node->mark_force_output ();
2424 else if (TREE_CODE (decl) == VAR_DECL)
2426 varpool_node *node = varpool_node::get_create (decl);
2427 /* C++ frontend use mark_decl_references to force COMDAT variables
2428 to be output that might appear dead otherwise. */
2429 node->force_output = true;
2431 /* else do nothing - we can get various sorts of CST nodes here,
2432 which do not need to be marked. */
2436 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS
2437 until we find an identifier that is not itself a transparent alias.
2438 Modify the alias passed to it by reference (and all aliases on the
2439 way to the ultimate target), such that they do not have to be
2440 followed again, and return the ultimate target of the alias
2441 chain. */
2443 static inline tree
2444 ultimate_transparent_alias_target (tree *alias)
2446 tree target = *alias;
2448 if (IDENTIFIER_TRANSPARENT_ALIAS (target))
2450 gcc_assert (TREE_CHAIN (target));
2451 target = ultimate_transparent_alias_target (&TREE_CHAIN (target));
2452 gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target)
2453 && ! TREE_CHAIN (target));
2454 *alias = target;
2457 return target;
2460 /* Output to FILE (an assembly file) a reference to NAME. If NAME
2461 starts with a *, the rest of NAME is output verbatim. Otherwise
2462 NAME is transformed in a target-specific way (usually by the
2463 addition of an underscore). */
2465 void
2466 assemble_name_raw (FILE *file, const char *name)
2468 if (name[0] == '*')
2469 fputs (&name[1], file);
2470 else
2471 ASM_OUTPUT_LABELREF (file, name);
2474 /* Like assemble_name_raw, but should be used when NAME might refer to
2475 an entity that is also represented as a tree (like a function or
2476 variable). If NAME does refer to such an entity, that entity will
2477 be marked as referenced. */
2479 void
2480 assemble_name (FILE *file, const char *name)
2482 const char *real_name;
2483 tree id;
2485 real_name = targetm.strip_name_encoding (name);
2487 id = maybe_get_identifier (real_name);
2488 if (id)
2490 tree id_orig = id;
2492 mark_referenced (id);
2493 ultimate_transparent_alias_target (&id);
2494 if (id != id_orig)
2495 name = IDENTIFIER_POINTER (id);
2496 gcc_assert (! TREE_CHAIN (id));
2499 assemble_name_raw (file, name);
2502 /* Allocate SIZE bytes writable static space with a gensym name
2503 and return an RTX to refer to its address. */
2506 assemble_static_space (unsigned HOST_WIDE_INT size)
2508 char name[12];
2509 const char *namestring;
2510 rtx x;
2512 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2513 ++const_labelno;
2514 namestring = ggc_strdup (name);
2516 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2517 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2519 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2520 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2521 BIGGEST_ALIGNMENT);
2522 #else
2523 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2524 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2525 #else
2527 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2528 so that each uninitialized object starts on such a boundary. */
2529 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2530 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2531 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2532 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2533 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2534 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2536 #endif
2537 #endif
2538 return x;
2541 /* Assemble the static constant template for function entry trampolines.
2542 This is done at most once per compilation.
2543 Returns an RTX for the address of the template. */
2545 static GTY(()) rtx initial_trampoline;
2548 assemble_trampoline_template (void)
2550 char label[256];
2551 const char *name;
2552 int align;
2553 rtx symbol;
2555 gcc_assert (targetm.asm_out.trampoline_template != NULL);
2557 if (initial_trampoline)
2558 return initial_trampoline;
2560 /* By default, put trampoline templates in read-only data section. */
2562 #ifdef TRAMPOLINE_SECTION
2563 switch_to_section (TRAMPOLINE_SECTION);
2564 #else
2565 switch_to_section (readonly_data_section);
2566 #endif
2568 /* Write the assembler code to define one. */
2569 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2570 if (align > 0)
2571 ASM_OUTPUT_ALIGN (asm_out_file, align);
2573 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2574 targetm.asm_out.trampoline_template (asm_out_file);
2576 /* Record the rtl to refer to it. */
2577 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2578 name = ggc_strdup (label);
2579 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2580 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2582 initial_trampoline = gen_const_mem (BLKmode, symbol);
2583 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2584 set_mem_size (initial_trampoline, TRAMPOLINE_SIZE);
2586 return initial_trampoline;
2589 /* A and B are either alignments or offsets. Return the minimum alignment
2590 that may be assumed after adding the two together. */
2592 static inline unsigned
2593 min_align (unsigned int a, unsigned int b)
2595 return (a | b) & -(a | b);
2598 /* Return the assembler directive for creating a given kind of integer
2599 object. SIZE is the number of bytes in the object and ALIGNED_P
2600 indicates whether it is known to be aligned. Return NULL if the
2601 assembly dialect has no such directive.
2603 The returned string should be printed at the start of a new line and
2604 be followed immediately by the object's initial value. */
2606 const char *
2607 integer_asm_op (int size, int aligned_p)
2609 struct asm_int_op *ops;
2611 if (aligned_p)
2612 ops = &targetm.asm_out.aligned_op;
2613 else
2614 ops = &targetm.asm_out.unaligned_op;
2616 switch (size)
2618 case 1:
2619 return targetm.asm_out.byte_op;
2620 case 2:
2621 return ops->hi;
2622 case 4:
2623 return ops->si;
2624 case 8:
2625 return ops->di;
2626 case 16:
2627 return ops->ti;
2628 default:
2629 return NULL;
2633 /* Use directive OP to assemble an integer object X. Print OP at the
2634 start of the line, followed immediately by the value of X. */
2636 void
2637 assemble_integer_with_op (const char *op, rtx x)
2639 fputs (op, asm_out_file);
2640 output_addr_const (asm_out_file, x);
2641 fputc ('\n', asm_out_file);
2644 /* The default implementation of the asm_out.integer target hook. */
2646 bool
2647 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2648 unsigned int size ATTRIBUTE_UNUSED,
2649 int aligned_p ATTRIBUTE_UNUSED)
2651 const char *op = integer_asm_op (size, aligned_p);
2652 /* Avoid GAS bugs for large values. Specifically negative values whose
2653 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2654 if (size > UNITS_PER_WORD && size > POINTER_SIZE_UNITS)
2655 return false;
2656 return op && (assemble_integer_with_op (op, x), true);
2659 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2660 the alignment of the integer in bits. Return 1 if we were able to output
2661 the constant, otherwise 0. We must be able to output the constant,
2662 if FORCE is nonzero. */
2664 bool
2665 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2667 int aligned_p;
2669 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2671 /* See if the target hook can handle this kind of object. */
2672 if (targetm.asm_out.integer (x, size, aligned_p))
2673 return true;
2675 /* If the object is a multi-byte one, try splitting it up. Split
2676 it into words it if is multi-word, otherwise split it into bytes. */
2677 if (size > 1)
2679 enum machine_mode omode, imode;
2680 unsigned int subalign;
2681 unsigned int subsize, i;
2682 enum mode_class mclass;
2684 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2685 subalign = MIN (align, subsize * BITS_PER_UNIT);
2686 if (GET_CODE (x) == CONST_FIXED)
2687 mclass = GET_MODE_CLASS (GET_MODE (x));
2688 else
2689 mclass = MODE_INT;
2691 omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0);
2692 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0);
2694 for (i = 0; i < size; i += subsize)
2696 rtx partial = simplify_subreg (omode, x, imode, i);
2697 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2698 break;
2700 if (i == size)
2701 return true;
2703 /* If we've printed some of it, but not all of it, there's no going
2704 back now. */
2705 gcc_assert (!i);
2708 gcc_assert (!force);
2710 return false;
2713 void
2714 assemble_real (REAL_VALUE_TYPE d, enum machine_mode mode, unsigned int align)
2716 long data[4] = {0, 0, 0, 0};
2717 int i;
2718 int bitsize, nelts, nunits, units_per;
2720 /* This is hairy. We have a quantity of known size. real_to_target
2721 will put it into an array of *host* longs, 32 bits per element
2722 (even if long is more than 32 bits). We need to determine the
2723 number of array elements that are occupied (nelts) and the number
2724 of *target* min-addressable units that will be occupied in the
2725 object file (nunits). We cannot assume that 32 divides the
2726 mode's bitsize (size * BITS_PER_UNIT) evenly.
2728 size * BITS_PER_UNIT is used here to make sure that padding bits
2729 (which might appear at either end of the value; real_to_target
2730 will include the padding bits in its output array) are included. */
2732 nunits = GET_MODE_SIZE (mode);
2733 bitsize = nunits * BITS_PER_UNIT;
2734 nelts = CEIL (bitsize, 32);
2735 units_per = 32 / BITS_PER_UNIT;
2737 real_to_target (data, &d, mode);
2739 /* Put out the first word with the specified alignment. */
2740 assemble_integer (GEN_INT (data[0]), MIN (nunits, units_per), align, 1);
2741 nunits -= units_per;
2743 /* Subsequent words need only 32-bit alignment. */
2744 align = min_align (align, 32);
2746 for (i = 1; i < nelts; i++)
2748 assemble_integer (GEN_INT (data[i]), MIN (nunits, units_per), align, 1);
2749 nunits -= units_per;
2753 /* Given an expression EXP with a constant value,
2754 reduce it to the sum of an assembler symbol and an integer.
2755 Store them both in the structure *VALUE.
2756 EXP must be reducible. */
2758 struct addr_const {
2759 rtx base;
2760 HOST_WIDE_INT offset;
2763 static void
2764 decode_addr_const (tree exp, struct addr_const *value)
2766 tree target = TREE_OPERAND (exp, 0);
2767 int offset = 0;
2768 rtx x;
2770 while (1)
2772 if (TREE_CODE (target) == COMPONENT_REF
2773 && tree_fits_shwi_p (byte_position (TREE_OPERAND (target, 1))))
2775 offset += int_byte_position (TREE_OPERAND (target, 1));
2776 target = TREE_OPERAND (target, 0);
2778 else if (TREE_CODE (target) == ARRAY_REF
2779 || TREE_CODE (target) == ARRAY_RANGE_REF)
2781 offset += (tree_to_uhwi (TYPE_SIZE_UNIT (TREE_TYPE (target)))
2782 * tree_to_shwi (TREE_OPERAND (target, 1)));
2783 target = TREE_OPERAND (target, 0);
2785 else if (TREE_CODE (target) == MEM_REF
2786 && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR)
2788 offset += mem_ref_offset (target).to_short_addr ();
2789 target = TREE_OPERAND (TREE_OPERAND (target, 0), 0);
2791 else if (TREE_CODE (target) == INDIRECT_REF
2792 && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR
2793 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0))
2794 == ADDR_EXPR)
2795 target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0);
2796 else
2797 break;
2800 switch (TREE_CODE (target))
2802 case VAR_DECL:
2803 case FUNCTION_DECL:
2804 x = DECL_RTL (target);
2805 break;
2807 case LABEL_DECL:
2808 x = gen_rtx_MEM (FUNCTION_MODE,
2809 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2810 break;
2812 case REAL_CST:
2813 case FIXED_CST:
2814 case STRING_CST:
2815 case COMPLEX_CST:
2816 case CONSTRUCTOR:
2817 case INTEGER_CST:
2818 x = output_constant_def (target, 1);
2819 break;
2821 default:
2822 gcc_unreachable ();
2825 gcc_assert (MEM_P (x));
2826 x = XEXP (x, 0);
2828 value->base = x;
2829 value->offset = offset;
2832 static GTY(()) hash_table<tree_descriptor_hasher> *const_desc_htab;
2834 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2836 /* Constant pool accessor function. */
2838 hash_table<tree_descriptor_hasher> *
2839 constant_pool_htab (void)
2841 return const_desc_htab;
2844 /* Compute a hash code for a constant expression. */
2846 hashval_t
2847 tree_descriptor_hasher::hash (constant_descriptor_tree *ptr)
2849 return ptr->hash;
2852 static hashval_t
2853 const_hash_1 (const tree exp)
2855 const char *p;
2856 hashval_t hi;
2857 int len, i;
2858 enum tree_code code = TREE_CODE (exp);
2860 /* Either set P and LEN to the address and len of something to hash and
2861 exit the switch or return a value. */
2863 switch (code)
2865 case INTEGER_CST:
2866 p = (char *) &TREE_INT_CST_ELT (exp, 0);
2867 len = TREE_INT_CST_NUNITS (exp) * sizeof (HOST_WIDE_INT);
2868 break;
2870 case REAL_CST:
2871 return real_hash (TREE_REAL_CST_PTR (exp));
2873 case FIXED_CST:
2874 return fixed_hash (TREE_FIXED_CST_PTR (exp));
2876 case STRING_CST:
2877 p = TREE_STRING_POINTER (exp);
2878 len = TREE_STRING_LENGTH (exp);
2879 break;
2881 case COMPLEX_CST:
2882 return (const_hash_1 (TREE_REALPART (exp)) * 5
2883 + const_hash_1 (TREE_IMAGPART (exp)));
2885 case VECTOR_CST:
2887 unsigned i;
2889 hi = 7 + VECTOR_CST_NELTS (exp);
2891 for (i = 0; i < VECTOR_CST_NELTS (exp); ++i)
2892 hi = hi * 563 + const_hash_1 (VECTOR_CST_ELT (exp, i));
2894 return hi;
2897 case CONSTRUCTOR:
2899 unsigned HOST_WIDE_INT idx;
2900 tree value;
2902 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2904 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
2905 if (value)
2906 hi = hi * 603 + const_hash_1 (value);
2908 return hi;
2911 case ADDR_EXPR:
2912 case FDESC_EXPR:
2914 struct addr_const value;
2916 decode_addr_const (exp, &value);
2917 switch (GET_CODE (value.base))
2919 case SYMBOL_REF:
2920 /* Don't hash the address of the SYMBOL_REF;
2921 only use the offset and the symbol name. */
2922 hi = value.offset;
2923 p = XSTR (value.base, 0);
2924 for (i = 0; p[i] != 0; i++)
2925 hi = ((hi * 613) + (unsigned) (p[i]));
2926 break;
2928 case LABEL_REF:
2929 hi = (value.offset
2930 + CODE_LABEL_NUMBER (LABEL_REF_LABEL (value.base)) * 13);
2931 break;
2933 default:
2934 gcc_unreachable ();
2937 return hi;
2939 case PLUS_EXPR:
2940 case POINTER_PLUS_EXPR:
2941 case MINUS_EXPR:
2942 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2943 + const_hash_1 (TREE_OPERAND (exp, 1)));
2945 CASE_CONVERT:
2946 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
2948 default:
2949 /* A language specific constant. Just hash the code. */
2950 return code;
2953 /* Compute hashing function. */
2954 hi = len;
2955 for (i = 0; i < len; i++)
2956 hi = ((hi * 613) + (unsigned) (p[i]));
2958 return hi;
2961 /* Wrapper of compare_constant, for the htab interface. */
2962 bool
2963 tree_descriptor_hasher::equal (constant_descriptor_tree *c1,
2964 constant_descriptor_tree *c2)
2966 if (c1->hash != c2->hash)
2967 return 0;
2968 return compare_constant (c1->value, c2->value);
2971 /* Compare t1 and t2, and return 1 only if they are known to result in
2972 the same bit pattern on output. */
2974 static int
2975 compare_constant (const tree t1, const tree t2)
2977 enum tree_code typecode;
2979 if (t1 == NULL_TREE)
2980 return t2 == NULL_TREE;
2981 if (t2 == NULL_TREE)
2982 return 0;
2984 if (TREE_CODE (t1) != TREE_CODE (t2))
2985 return 0;
2987 switch (TREE_CODE (t1))
2989 case INTEGER_CST:
2990 /* Integer constants are the same only if the same width of type. */
2991 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2992 return 0;
2993 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2994 return 0;
2995 return tree_int_cst_equal (t1, t2);
2997 case REAL_CST:
2998 /* Real constants are the same only if the same width of type. */
2999 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3000 return 0;
3002 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
3004 case FIXED_CST:
3005 /* Fixed constants are the same only if the same width of type. */
3006 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3007 return 0;
3009 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
3011 case STRING_CST:
3012 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3013 return 0;
3015 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
3016 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
3017 TREE_STRING_LENGTH (t1)));
3019 case COMPLEX_CST:
3020 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
3021 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
3023 case VECTOR_CST:
3025 unsigned i;
3027 if (VECTOR_CST_NELTS (t1) != VECTOR_CST_NELTS (t2))
3028 return 0;
3030 for (i = 0; i < VECTOR_CST_NELTS (t1); ++i)
3031 if (!compare_constant (VECTOR_CST_ELT (t1, i),
3032 VECTOR_CST_ELT (t2, i)))
3033 return 0;
3035 return 1;
3038 case CONSTRUCTOR:
3040 vec<constructor_elt, va_gc> *v1, *v2;
3041 unsigned HOST_WIDE_INT idx;
3043 typecode = TREE_CODE (TREE_TYPE (t1));
3044 if (typecode != TREE_CODE (TREE_TYPE (t2)))
3045 return 0;
3047 if (typecode == ARRAY_TYPE)
3049 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
3050 /* For arrays, check that the sizes all match. */
3051 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
3052 || size_1 == -1
3053 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
3054 return 0;
3056 else
3058 /* For record and union constructors, require exact type
3059 equality. */
3060 if (TREE_TYPE (t1) != TREE_TYPE (t2))
3061 return 0;
3064 v1 = CONSTRUCTOR_ELTS (t1);
3065 v2 = CONSTRUCTOR_ELTS (t2);
3066 if (vec_safe_length (v1) != vec_safe_length (v2))
3067 return 0;
3069 for (idx = 0; idx < vec_safe_length (v1); ++idx)
3071 constructor_elt *c1 = &(*v1)[idx];
3072 constructor_elt *c2 = &(*v2)[idx];
3074 /* Check that each value is the same... */
3075 if (!compare_constant (c1->value, c2->value))
3076 return 0;
3077 /* ... and that they apply to the same fields! */
3078 if (typecode == ARRAY_TYPE)
3080 if (!compare_constant (c1->index, c2->index))
3081 return 0;
3083 else
3085 if (c1->index != c2->index)
3086 return 0;
3090 return 1;
3093 case ADDR_EXPR:
3094 case FDESC_EXPR:
3096 struct addr_const value1, value2;
3097 enum rtx_code code;
3098 int ret;
3100 decode_addr_const (t1, &value1);
3101 decode_addr_const (t2, &value2);
3103 if (value1.offset != value2.offset)
3104 return 0;
3106 code = GET_CODE (value1.base);
3107 if (code != GET_CODE (value2.base))
3108 return 0;
3110 switch (code)
3112 case SYMBOL_REF:
3113 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3114 break;
3116 case LABEL_REF:
3117 ret = (CODE_LABEL_NUMBER (LABEL_REF_LABEL (value1.base))
3118 == CODE_LABEL_NUMBER (LABEL_REF_LABEL (value2.base)));
3119 break;
3121 default:
3122 gcc_unreachable ();
3124 return ret;
3127 case PLUS_EXPR:
3128 case POINTER_PLUS_EXPR:
3129 case MINUS_EXPR:
3130 case RANGE_EXPR:
3131 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3132 && compare_constant (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3134 CASE_CONVERT:
3135 case VIEW_CONVERT_EXPR:
3136 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3138 default:
3139 return 0;
3142 gcc_unreachable ();
3145 /* Return the section into which constant EXP should be placed. */
3147 static section *
3148 get_constant_section (tree exp, unsigned int align)
3150 return targetm.asm_out.select_section (exp,
3151 compute_reloc_for_constant (exp),
3152 align);
3155 /* Return the size of constant EXP in bytes. */
3157 static HOST_WIDE_INT
3158 get_constant_size (tree exp)
3160 HOST_WIDE_INT size;
3162 size = int_size_in_bytes (TREE_TYPE (exp));
3163 if (TREE_CODE (exp) == STRING_CST)
3164 size = MAX (TREE_STRING_LENGTH (exp), size);
3165 return size;
3168 /* Subroutine of output_constant_def:
3169 No constant equal to EXP is known to have been output.
3170 Make a constant descriptor to enter EXP in the hash table.
3171 Assign the label number and construct RTL to refer to the
3172 constant's location in memory.
3173 Caller is responsible for updating the hash table. */
3175 static struct constant_descriptor_tree *
3176 build_constant_desc (tree exp)
3178 struct constant_descriptor_tree *desc;
3179 rtx symbol, rtl;
3180 char label[256];
3181 int labelno;
3182 tree decl;
3184 desc = ggc_alloc<constant_descriptor_tree> ();
3185 desc->value = exp;
3187 /* Create a string containing the label name, in LABEL. */
3188 labelno = const_labelno++;
3189 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3191 /* Construct the VAR_DECL associated with the constant. */
3192 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3193 TREE_TYPE (exp));
3194 DECL_ARTIFICIAL (decl) = 1;
3195 DECL_IGNORED_P (decl) = 1;
3196 TREE_READONLY (decl) = 1;
3197 TREE_STATIC (decl) = 1;
3198 TREE_ADDRESSABLE (decl) = 1;
3199 /* We don't set the RTL yet as this would cause varpool to assume that the
3200 variable is referenced. Moreover, it would just be dropped in LTO mode.
3201 Instead we set the flag that will be recognized in make_decl_rtl. */
3202 DECL_IN_CONSTANT_POOL (decl) = 1;
3203 DECL_INITIAL (decl) = desc->value;
3204 /* ??? CONSTANT_ALIGNMENT hasn't been updated for vector types on most
3205 architectures so use DATA_ALIGNMENT as well, except for strings. */
3206 if (TREE_CODE (exp) == STRING_CST)
3208 #ifdef CONSTANT_ALIGNMENT
3209 DECL_ALIGN (decl) = CONSTANT_ALIGNMENT (exp, DECL_ALIGN (decl));
3210 #endif
3212 else
3213 align_variable (decl, 0);
3215 /* Now construct the SYMBOL_REF and the MEM. */
3216 if (use_object_blocks_p ())
3218 section *sect = get_constant_section (exp, DECL_ALIGN (decl));
3219 symbol = create_block_symbol (ggc_strdup (label),
3220 get_block_for_section (sect), -1);
3222 else
3223 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3224 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3225 SET_SYMBOL_REF_DECL (symbol, decl);
3226 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3228 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3229 set_mem_attributes (rtl, exp, 1);
3230 set_mem_alias_set (rtl, 0);
3231 set_mem_alias_set (rtl, const_alias_set);
3233 /* We cannot share RTX'es in pool entries.
3234 Mark this piece of RTL as required for unsharing. */
3235 RTX_FLAG (rtl, used) = 1;
3237 /* Set flags or add text to the name to record information, such as
3238 that it is a local symbol. If the name is changed, the macro
3239 ASM_OUTPUT_LABELREF will have to know how to strip this
3240 information. This call might invalidate our local variable
3241 SYMBOL; we can't use it afterward. */
3242 targetm.encode_section_info (exp, rtl, true);
3244 desc->rtl = rtl;
3246 return desc;
3249 /* Return an rtx representing a reference to constant data in memory
3250 for the constant expression EXP.
3252 If assembler code for such a constant has already been output,
3253 return an rtx to refer to it.
3254 Otherwise, output such a constant in memory
3255 and generate an rtx for it.
3257 If DEFER is nonzero, this constant can be deferred and output only
3258 if referenced in the function after all optimizations.
3260 `const_desc_table' records which constants already have label strings. */
3263 output_constant_def (tree exp, int defer)
3265 struct constant_descriptor_tree *desc;
3266 struct constant_descriptor_tree key;
3268 /* Look up EXP in the table of constant descriptors. If we didn't find
3269 it, create a new one. */
3270 key.value = exp;
3271 key.hash = const_hash_1 (exp);
3272 constant_descriptor_tree **loc
3273 = const_desc_htab->find_slot_with_hash (&key, key.hash, INSERT);
3275 desc = *loc;
3276 if (desc == 0)
3278 desc = build_constant_desc (exp);
3279 desc->hash = key.hash;
3280 *loc = desc;
3283 maybe_output_constant_def_contents (desc, defer);
3284 return desc->rtl;
3287 /* Subroutine of output_constant_def: Decide whether or not we need to
3288 output the constant DESC now, and if so, do it. */
3289 static void
3290 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3291 int defer)
3293 rtx symbol = XEXP (desc->rtl, 0);
3294 tree exp = desc->value;
3296 if (flag_syntax_only)
3297 return;
3299 if (TREE_ASM_WRITTEN (exp))
3300 /* Already output; don't do it again. */
3301 return;
3303 /* We can always defer constants as long as the context allows
3304 doing so. */
3305 if (defer)
3307 /* Increment n_deferred_constants if it exists. It needs to be at
3308 least as large as the number of constants actually referred to
3309 by the function. If it's too small we'll stop looking too early
3310 and fail to emit constants; if it's too large we'll only look
3311 through the entire function when we could have stopped earlier. */
3312 if (cfun)
3313 n_deferred_constants++;
3314 return;
3317 output_constant_def_contents (symbol);
3320 /* Subroutine of output_constant_def_contents. Output the definition
3321 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3322 constant's alignment in bits. */
3324 static void
3325 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3327 HOST_WIDE_INT size;
3329 size = get_constant_size (exp);
3331 /* Do any machine/system dependent processing of the constant. */
3332 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3334 /* Output the value of EXP. */
3335 output_constant (exp, size, align);
3338 /* We must output the constant data referred to by SYMBOL; do so. */
3340 static void
3341 output_constant_def_contents (rtx symbol)
3343 tree decl = SYMBOL_REF_DECL (symbol);
3344 tree exp = DECL_INITIAL (decl);
3345 unsigned int align;
3346 bool asan_protected = false;
3348 /* Make sure any other constants whose addresses appear in EXP
3349 are assigned label numbers. */
3350 output_addressed_constants (exp);
3352 /* We are no longer deferring this constant. */
3353 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3355 if ((flag_sanitize & SANITIZE_ADDRESS)
3356 && TREE_CODE (exp) == STRING_CST
3357 && asan_protect_global (exp))
3359 asan_protected = true;
3360 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
3361 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
3364 /* If the constant is part of an object block, make sure that the
3365 decl has been positioned within its block, but do not write out
3366 its definition yet. output_object_blocks will do that later. */
3367 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3368 place_block_symbol (symbol);
3369 else
3371 align = DECL_ALIGN (decl);
3372 switch_to_section (get_constant_section (exp, align));
3373 if (align > BITS_PER_UNIT)
3374 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3375 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3376 if (asan_protected)
3378 HOST_WIDE_INT size = get_constant_size (exp);
3379 assemble_zeros (asan_red_zone_size (size));
3384 /* Look up EXP in the table of constant descriptors. Return the rtl
3385 if it has been emitted, else null. */
3388 lookup_constant_def (tree exp)
3390 struct constant_descriptor_tree key;
3392 key.value = exp;
3393 key.hash = const_hash_1 (exp);
3394 constant_descriptor_tree *desc
3395 = const_desc_htab->find_with_hash (&key, key.hash);
3397 return (desc ? desc->rtl : NULL_RTX);
3400 /* Return a tree representing a reference to constant data in memory
3401 for the constant expression EXP.
3403 This is the counterpart of output_constant_def at the Tree level. */
3405 tree
3406 tree_output_constant_def (tree exp)
3408 struct constant_descriptor_tree *desc, key;
3409 tree decl;
3411 /* Look up EXP in the table of constant descriptors. If we didn't find
3412 it, create a new one. */
3413 key.value = exp;
3414 key.hash = const_hash_1 (exp);
3415 constant_descriptor_tree **loc
3416 = const_desc_htab->find_slot_with_hash (&key, key.hash, INSERT);
3418 desc = *loc;
3419 if (desc == 0)
3421 desc = build_constant_desc (exp);
3422 desc->hash = key.hash;
3423 *loc = desc;
3426 decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3427 varpool_node::finalize_decl (decl);
3428 return decl;
3431 struct GTY((chain_next ("%h.next"), for_user)) constant_descriptor_rtx {
3432 struct constant_descriptor_rtx *next;
3433 rtx mem;
3434 rtx sym;
3435 rtx constant;
3436 HOST_WIDE_INT offset;
3437 hashval_t hash;
3438 enum machine_mode mode;
3439 unsigned int align;
3440 int labelno;
3441 int mark;
3444 struct const_rtx_desc_hasher : ggc_hasher<constant_descriptor_rtx *>
3446 static hashval_t hash (constant_descriptor_rtx *);
3447 static bool equal (constant_descriptor_rtx *, constant_descriptor_rtx *);
3450 /* Used in the hash tables to avoid outputting the same constant
3451 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3452 are output once per function, not once per file. */
3453 /* ??? Only a few targets need per-function constant pools. Most
3454 can use one per-file pool. Should add a targetm bit to tell the
3455 difference. */
3457 struct GTY(()) rtx_constant_pool {
3458 /* Pointers to first and last constant in pool, as ordered by offset. */
3459 struct constant_descriptor_rtx *first;
3460 struct constant_descriptor_rtx *last;
3462 /* Hash facility for making memory-constants from constant rtl-expressions.
3463 It is used on RISC machines where immediate integer arguments and
3464 constant addresses are restricted so that such constants must be stored
3465 in memory. */
3466 hash_table<const_rtx_desc_hasher> *const_rtx_htab;
3468 /* Current offset in constant pool (does not include any
3469 machine-specific header). */
3470 HOST_WIDE_INT offset;
3473 /* Hash and compare functions for const_rtx_htab. */
3475 hashval_t
3476 const_rtx_desc_hasher::hash (constant_descriptor_rtx *desc)
3478 return desc->hash;
3481 bool
3482 const_rtx_desc_hasher::equal (constant_descriptor_rtx *x,
3483 constant_descriptor_rtx *y)
3485 if (x->mode != y->mode)
3486 return 0;
3487 return rtx_equal_p (x->constant, y->constant);
3490 /* Hash one component of a constant. */
3492 static hashval_t
3493 const_rtx_hash_1 (const_rtx x)
3495 unsigned HOST_WIDE_INT hwi;
3496 enum machine_mode mode;
3497 enum rtx_code code;
3498 hashval_t h;
3499 int i;
3501 code = GET_CODE (x);
3502 mode = GET_MODE (x);
3503 h = (hashval_t) code * 1048573 + mode;
3505 switch (code)
3507 case CONST_INT:
3508 hwi = INTVAL (x);
3510 fold_hwi:
3512 int shift = sizeof (hashval_t) * CHAR_BIT;
3513 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3515 h ^= (hashval_t) hwi;
3516 for (i = 1; i < n; ++i)
3518 hwi >>= shift;
3519 h ^= (hashval_t) hwi;
3522 break;
3524 case CONST_WIDE_INT:
3525 hwi = GET_MODE_PRECISION (mode);
3527 for (i = 0; i < CONST_WIDE_INT_NUNITS (x); i++)
3528 hwi ^= CONST_WIDE_INT_ELT (x, i);
3529 goto fold_hwi;
3532 case CONST_DOUBLE:
3533 if (TARGET_SUPPORTS_WIDE_INT == 0 && mode == VOIDmode)
3535 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3536 goto fold_hwi;
3538 else
3539 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3540 break;
3542 case CONST_FIXED:
3543 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3544 break;
3546 case SYMBOL_REF:
3547 h ^= htab_hash_string (XSTR (x, 0));
3548 break;
3550 case LABEL_REF:
3551 h = h * 251 + CODE_LABEL_NUMBER (LABEL_REF_LABEL (x));
3552 break;
3554 case UNSPEC:
3555 case UNSPEC_VOLATILE:
3556 h = h * 251 + XINT (x, 1);
3557 break;
3559 default:
3560 break;
3563 return h;
3566 /* Compute a hash value for X, which should be a constant. */
3568 static hashval_t
3569 const_rtx_hash (rtx x)
3571 hashval_t h = 0;
3572 subrtx_iterator::array_type array;
3573 FOR_EACH_SUBRTX (iter, array, x, ALL)
3574 h = h * 509 + const_rtx_hash_1 (*iter);
3575 return h;
3579 /* Create and return a new rtx constant pool. */
3581 static struct rtx_constant_pool *
3582 create_constant_pool (void)
3584 struct rtx_constant_pool *pool;
3586 pool = ggc_alloc<rtx_constant_pool> ();
3587 pool->const_rtx_htab = hash_table<const_rtx_desc_hasher>::create_ggc (31);
3588 pool->first = NULL;
3589 pool->last = NULL;
3590 pool->offset = 0;
3591 return pool;
3594 /* Initialize constant pool hashing for a new function. */
3596 void
3597 init_varasm_status (void)
3599 crtl->varasm.pool = create_constant_pool ();
3600 crtl->varasm.deferred_constants = 0;
3603 /* Given a MINUS expression, simplify it if both sides
3604 include the same symbol. */
3607 simplify_subtraction (rtx x)
3609 rtx r = simplify_rtx (x);
3610 return r ? r : x;
3613 /* Given a constant rtx X, make (or find) a memory constant for its value
3614 and return a MEM rtx to refer to it in memory. */
3617 force_const_mem (enum machine_mode mode, rtx x)
3619 struct constant_descriptor_rtx *desc, tmp;
3620 struct rtx_constant_pool *pool;
3621 char label[256];
3622 rtx def, symbol;
3623 hashval_t hash;
3624 unsigned int align;
3625 constant_descriptor_rtx **slot;
3627 /* If we're not allowed to drop X into the constant pool, don't. */
3628 if (targetm.cannot_force_const_mem (mode, x))
3629 return NULL_RTX;
3631 /* Record that this function has used a constant pool entry. */
3632 crtl->uses_const_pool = 1;
3634 /* Decide which pool to use. */
3635 pool = (targetm.use_blocks_for_constant_p (mode, x)
3636 ? shared_constant_pool
3637 : crtl->varasm.pool);
3639 /* Lookup the value in the hashtable. */
3640 tmp.constant = x;
3641 tmp.mode = mode;
3642 hash = const_rtx_hash (x);
3643 slot = pool->const_rtx_htab->find_slot_with_hash (&tmp, hash, INSERT);
3644 desc = *slot;
3646 /* If the constant was already present, return its memory. */
3647 if (desc)
3648 return copy_rtx (desc->mem);
3650 /* Otherwise, create a new descriptor. */
3651 desc = ggc_alloc<constant_descriptor_rtx> ();
3652 *slot = desc;
3654 /* Align the location counter as required by EXP's data type. */
3655 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3656 #ifdef CONSTANT_ALIGNMENT
3658 tree type = lang_hooks.types.type_for_mode (mode, 0);
3659 if (type != NULL_TREE)
3660 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3662 #endif
3664 pool->offset += (align / BITS_PER_UNIT) - 1;
3665 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3667 desc->next = NULL;
3668 desc->constant = copy_rtx (tmp.constant);
3669 desc->offset = pool->offset;
3670 desc->hash = hash;
3671 desc->mode = mode;
3672 desc->align = align;
3673 desc->labelno = const_labelno;
3674 desc->mark = 0;
3676 pool->offset += GET_MODE_SIZE (mode);
3677 if (pool->last)
3678 pool->last->next = desc;
3679 else
3680 pool->first = pool->last = desc;
3681 pool->last = desc;
3683 /* Create a string containing the label name, in LABEL. */
3684 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3685 ++const_labelno;
3687 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3688 the constants pool. */
3689 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3691 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3692 symbol = create_block_symbol (ggc_strdup (label),
3693 get_block_for_section (sect), -1);
3695 else
3696 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3697 desc->sym = symbol;
3698 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3699 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3700 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3702 /* Construct the MEM. */
3703 desc->mem = def = gen_const_mem (mode, symbol);
3704 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3705 set_mem_align (def, align);
3707 /* If we're dropping a label to the constant pool, make sure we
3708 don't delete it. */
3709 if (GET_CODE (x) == LABEL_REF)
3710 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3712 return copy_rtx (def);
3715 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3718 get_pool_constant (const_rtx addr)
3720 return SYMBOL_REF_CONSTANT (addr)->constant;
3723 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3724 and whether it has been output or not. */
3727 get_pool_constant_mark (rtx addr, bool *pmarked)
3729 struct constant_descriptor_rtx *desc;
3731 desc = SYMBOL_REF_CONSTANT (addr);
3732 *pmarked = (desc->mark != 0);
3733 return desc->constant;
3736 /* Similar, return the mode. */
3738 enum machine_mode
3739 get_pool_mode (const_rtx addr)
3741 return SYMBOL_REF_CONSTANT (addr)->mode;
3744 /* Return the size of the constant pool. */
3747 get_pool_size (void)
3749 return crtl->varasm.pool->offset;
3752 /* Worker function for output_constant_pool_1. Emit assembly for X
3753 in MODE with known alignment ALIGN. */
3755 static void
3756 output_constant_pool_2 (enum machine_mode mode, rtx x, unsigned int align)
3758 switch (GET_MODE_CLASS (mode))
3760 case MODE_FLOAT:
3761 case MODE_DECIMAL_FLOAT:
3763 REAL_VALUE_TYPE r;
3765 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3766 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3767 assemble_real (r, mode, align);
3768 break;
3771 case MODE_INT:
3772 case MODE_PARTIAL_INT:
3773 case MODE_FRACT:
3774 case MODE_UFRACT:
3775 case MODE_ACCUM:
3776 case MODE_UACCUM:
3777 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3778 break;
3780 case MODE_VECTOR_FLOAT:
3781 case MODE_VECTOR_INT:
3782 case MODE_VECTOR_FRACT:
3783 case MODE_VECTOR_UFRACT:
3784 case MODE_VECTOR_ACCUM:
3785 case MODE_VECTOR_UACCUM:
3787 int i, units;
3788 enum machine_mode submode = GET_MODE_INNER (mode);
3789 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3791 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3792 units = CONST_VECTOR_NUNITS (x);
3794 for (i = 0; i < units; i++)
3796 rtx elt = CONST_VECTOR_ELT (x, i);
3797 output_constant_pool_2 (submode, elt, i ? subalign : align);
3800 break;
3802 default:
3803 gcc_unreachable ();
3807 /* Worker function for output_constant_pool. Emit constant DESC,
3808 giving it ALIGN bits of alignment. */
3810 static void
3811 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3812 unsigned int align)
3814 rtx x, tmp;
3816 x = desc->constant;
3818 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3819 whose CODE_LABEL has been deleted. This can occur if a jump table
3820 is eliminated by optimization. If so, write a constant of zero
3821 instead. Note that this can also happen by turning the
3822 CODE_LABEL into a NOTE. */
3823 /* ??? This seems completely and utterly wrong. Certainly it's
3824 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3825 functioning even with rtx_insn::deleted and friends. */
3827 tmp = x;
3828 switch (GET_CODE (tmp))
3830 case CONST:
3831 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3832 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
3833 break;
3834 tmp = XEXP (XEXP (tmp, 0), 0);
3835 /* FALLTHRU */
3837 case LABEL_REF:
3838 tmp = LABEL_REF_LABEL (tmp);
3839 gcc_assert (!as_a<rtx_insn *> (tmp)->deleted ());
3840 gcc_assert (!NOTE_P (tmp)
3841 || NOTE_KIND (tmp) != NOTE_INSN_DELETED);
3842 break;
3844 default:
3845 break;
3848 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3849 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3850 align, desc->labelno, done);
3851 #endif
3853 assemble_align (align);
3855 /* Output the label. */
3856 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3858 /* Output the data. */
3859 output_constant_pool_2 (desc->mode, x, align);
3861 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3862 sections have proper size. */
3863 if (align > GET_MODE_BITSIZE (desc->mode)
3864 && in_section
3865 && (in_section->common.flags & SECTION_MERGE))
3866 assemble_align (align);
3868 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3869 done:
3870 #endif
3871 return;
3874 /* Mark all constants that are referenced by SYMBOL_REFs in X.
3875 Emit referenced deferred strings. */
3877 static void
3878 mark_constants_in_pattern (rtx insn)
3880 subrtx_iterator::array_type array;
3881 FOR_EACH_SUBRTX (iter, array, PATTERN (insn), ALL)
3883 const_rtx x = *iter;
3884 if (GET_CODE (x) == SYMBOL_REF)
3886 if (CONSTANT_POOL_ADDRESS_P (x))
3888 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
3889 if (desc->mark == 0)
3891 desc->mark = 1;
3892 iter.substitute (desc->constant);
3895 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3897 tree decl = SYMBOL_REF_DECL (x);
3898 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
3900 n_deferred_constants--;
3901 output_constant_def_contents (CONST_CAST_RTX (x));
3908 /* Look through appropriate parts of INSN, marking all entries in the
3909 constant pool which are actually being used. Entries that are only
3910 referenced by other constants are also marked as used. Emit
3911 deferred strings that are used. */
3913 static void
3914 mark_constants (rtx_insn *insn)
3916 if (!INSN_P (insn))
3917 return;
3919 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3920 insns, not any notes that may be attached. We don't want to mark
3921 a constant just because it happens to appear in a REG_EQUIV note. */
3922 if (rtx_sequence *seq = dyn_cast <rtx_sequence *> (PATTERN (insn)))
3924 int i, n = seq->len ();
3925 for (i = 0; i < n; ++i)
3927 rtx subinsn = seq->element (i);
3928 if (INSN_P (subinsn))
3929 mark_constants_in_pattern (subinsn);
3932 else
3933 mark_constants_in_pattern (insn);
3936 /* Look through the instructions for this function, and mark all the
3937 entries in POOL which are actually being used. Emit deferred constants
3938 which have indeed been used. */
3940 static void
3941 mark_constant_pool (void)
3943 rtx_insn *insn;
3945 if (!crtl->uses_const_pool && n_deferred_constants == 0)
3946 return;
3948 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3949 mark_constants (insn);
3952 /* Write all the constants in POOL. */
3954 static void
3955 output_constant_pool_contents (struct rtx_constant_pool *pool)
3957 struct constant_descriptor_rtx *desc;
3959 for (desc = pool->first; desc ; desc = desc->next)
3960 if (desc->mark)
3962 /* If the constant is part of an object_block, make sure that
3963 the constant has been positioned within its block, but do not
3964 write out its definition yet. output_object_blocks will do
3965 that later. */
3966 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
3967 && SYMBOL_REF_BLOCK (desc->sym))
3968 place_block_symbol (desc->sym);
3969 else
3971 switch_to_section (targetm.asm_out.select_rtx_section
3972 (desc->mode, desc->constant, desc->align));
3973 output_constant_pool_1 (desc, desc->align);
3978 /* Mark all constants that are used in the current function, then write
3979 out the function's private constant pool. */
3981 static void
3982 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
3983 tree fndecl ATTRIBUTE_UNUSED)
3985 struct rtx_constant_pool *pool = crtl->varasm.pool;
3987 /* It is possible for gcc to call force_const_mem and then to later
3988 discard the instructions which refer to the constant. In such a
3989 case we do not need to output the constant. */
3990 mark_constant_pool ();
3992 #ifdef ASM_OUTPUT_POOL_PROLOGUE
3993 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
3994 #endif
3996 output_constant_pool_contents (pool);
3998 #ifdef ASM_OUTPUT_POOL_EPILOGUE
3999 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
4000 #endif
4003 /* Write the contents of the shared constant pool. */
4005 void
4006 output_shared_constant_pool (void)
4008 output_constant_pool_contents (shared_constant_pool);
4011 /* Determine what kind of relocations EXP may need. */
4014 compute_reloc_for_constant (tree exp)
4016 int reloc = 0, reloc2;
4017 tree tem;
4019 switch (TREE_CODE (exp))
4021 case ADDR_EXPR:
4022 case FDESC_EXPR:
4023 /* Go inside any operations that get_inner_reference can handle and see
4024 if what's inside is a constant: no need to do anything here for
4025 addresses of variables or functions. */
4026 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4027 tem = TREE_OPERAND (tem, 0))
4030 if (TREE_CODE (tem) == MEM_REF
4031 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4033 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4034 break;
4037 if (!targetm.binds_local_p (tem))
4038 reloc |= 2;
4039 else
4040 reloc |= 1;
4041 break;
4043 case PLUS_EXPR:
4044 case POINTER_PLUS_EXPR:
4045 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4046 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4047 break;
4049 case MINUS_EXPR:
4050 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4051 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4052 /* The difference of two local labels is computable at link time. */
4053 if (reloc == 1 && reloc2 == 1)
4054 reloc = 0;
4055 else
4056 reloc |= reloc2;
4057 break;
4059 CASE_CONVERT:
4060 case VIEW_CONVERT_EXPR:
4061 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4062 break;
4064 case CONSTRUCTOR:
4066 unsigned HOST_WIDE_INT idx;
4067 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4068 if (tem != 0)
4069 reloc |= compute_reloc_for_constant (tem);
4071 break;
4073 default:
4074 break;
4076 return reloc;
4079 /* Find all the constants whose addresses are referenced inside of EXP,
4080 and make sure assembler code with a label has been output for each one.
4081 Indicate whether an ADDR_EXPR has been encountered. */
4083 static void
4084 output_addressed_constants (tree exp)
4086 tree tem;
4088 switch (TREE_CODE (exp))
4090 case ADDR_EXPR:
4091 case FDESC_EXPR:
4092 /* Go inside any operations that get_inner_reference can handle and see
4093 if what's inside is a constant: no need to do anything here for
4094 addresses of variables or functions. */
4095 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4096 tem = TREE_OPERAND (tem, 0))
4099 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4100 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4101 tem = DECL_INITIAL (tem);
4103 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4104 output_constant_def (tem, 0);
4106 if (TREE_CODE (tem) == MEM_REF)
4107 output_addressed_constants (TREE_OPERAND (tem, 0));
4108 break;
4110 case PLUS_EXPR:
4111 case POINTER_PLUS_EXPR:
4112 case MINUS_EXPR:
4113 output_addressed_constants (TREE_OPERAND (exp, 1));
4114 /* Fall through. */
4116 CASE_CONVERT:
4117 case VIEW_CONVERT_EXPR:
4118 output_addressed_constants (TREE_OPERAND (exp, 0));
4119 break;
4121 case CONSTRUCTOR:
4123 unsigned HOST_WIDE_INT idx;
4124 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4125 if (tem != 0)
4126 output_addressed_constants (tem);
4128 break;
4130 default:
4131 break;
4135 /* Whether a constructor CTOR is a valid static constant initializer if all
4136 its elements are. This used to be internal to initializer_constant_valid_p
4137 and has been exposed to let other functions like categorize_ctor_elements
4138 evaluate the property while walking a constructor for other purposes. */
4140 bool
4141 constructor_static_from_elts_p (const_tree ctor)
4143 return (TREE_CONSTANT (ctor)
4144 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4145 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4146 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4149 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4150 tree *cache);
4152 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4153 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4154 which are valid when ENDTYPE is an integer of any size; in
4155 particular, this does not accept a pointer minus a constant. This
4156 returns null_pointer_node if the VALUE is an absolute constant
4157 which can be used to initialize a static variable. Otherwise it
4158 returns NULL. */
4160 static tree
4161 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4163 tree op0, op1;
4165 if (!INTEGRAL_TYPE_P (endtype))
4166 return NULL_TREE;
4168 op0 = TREE_OPERAND (value, 0);
4169 op1 = TREE_OPERAND (value, 1);
4171 /* Like STRIP_NOPS except allow the operand mode to widen. This
4172 works around a feature of fold that simplifies (int)(p1 - p2) to
4173 ((int)p1 - (int)p2) under the theory that the narrower operation
4174 is cheaper. */
4176 while (CONVERT_EXPR_P (op0)
4177 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4179 tree inner = TREE_OPERAND (op0, 0);
4180 if (inner == error_mark_node
4181 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4182 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
4183 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4184 break;
4185 op0 = inner;
4188 while (CONVERT_EXPR_P (op1)
4189 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4191 tree inner = TREE_OPERAND (op1, 0);
4192 if (inner == error_mark_node
4193 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4194 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
4195 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4196 break;
4197 op1 = inner;
4200 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4201 if (!op0)
4202 return NULL_TREE;
4204 op1 = initializer_constant_valid_p_1 (op1, endtype,
4205 cache ? cache + 2 : NULL);
4206 /* Both initializers must be known. */
4207 if (op1)
4209 if (op0 == op1
4210 && (op0 == null_pointer_node
4211 || TREE_CODE (value) == MINUS_EXPR))
4212 return null_pointer_node;
4214 /* Support differences between labels. */
4215 if (TREE_CODE (op0) == LABEL_DECL
4216 && TREE_CODE (op1) == LABEL_DECL)
4217 return null_pointer_node;
4219 if (TREE_CODE (op0) == STRING_CST
4220 && TREE_CODE (op1) == STRING_CST
4221 && operand_equal_p (op0, op1, 1))
4222 return null_pointer_node;
4225 return NULL_TREE;
4228 /* Helper function of initializer_constant_valid_p.
4229 Return nonzero if VALUE is a valid constant-valued expression
4230 for use in initializing a static variable; one that can be an
4231 element of a "constant" initializer.
4233 Return null_pointer_node if the value is absolute;
4234 if it is relocatable, return the variable that determines the relocation.
4235 We assume that VALUE has been folded as much as possible;
4236 therefore, we do not need to check for such things as
4237 arithmetic-combinations of integers.
4239 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4241 static tree
4242 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4244 tree ret;
4246 switch (TREE_CODE (value))
4248 case CONSTRUCTOR:
4249 if (constructor_static_from_elts_p (value))
4251 unsigned HOST_WIDE_INT idx;
4252 tree elt;
4253 bool absolute = true;
4255 if (cache && cache[0] == value)
4256 return cache[1];
4257 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4259 tree reloc;
4260 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4261 NULL);
4262 if (!reloc)
4264 if (cache)
4266 cache[0] = value;
4267 cache[1] = NULL_TREE;
4269 return NULL_TREE;
4271 if (reloc != null_pointer_node)
4272 absolute = false;
4274 /* For a non-absolute relocation, there is no single
4275 variable that can be "the variable that determines the
4276 relocation." */
4277 if (cache)
4279 cache[0] = value;
4280 cache[1] = absolute ? null_pointer_node : error_mark_node;
4282 return absolute ? null_pointer_node : error_mark_node;
4285 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4287 case INTEGER_CST:
4288 case VECTOR_CST:
4289 case REAL_CST:
4290 case FIXED_CST:
4291 case STRING_CST:
4292 case COMPLEX_CST:
4293 return null_pointer_node;
4295 case ADDR_EXPR:
4296 case FDESC_EXPR:
4298 tree op0 = staticp (TREE_OPERAND (value, 0));
4299 if (op0)
4301 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4302 to be a constant, this is old-skool offsetof-like nonsense. */
4303 if (TREE_CODE (op0) == INDIRECT_REF
4304 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4305 return null_pointer_node;
4306 /* Taking the address of a nested function involves a trampoline,
4307 unless we don't need or want one. */
4308 if (TREE_CODE (op0) == FUNCTION_DECL
4309 && DECL_STATIC_CHAIN (op0)
4310 && !TREE_NO_TRAMPOLINE (value))
4311 return NULL_TREE;
4312 /* "&{...}" requires a temporary to hold the constructed
4313 object. */
4314 if (TREE_CODE (op0) == CONSTRUCTOR)
4315 return NULL_TREE;
4317 return op0;
4320 case NON_LVALUE_EXPR:
4321 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4322 endtype, cache);
4324 case VIEW_CONVERT_EXPR:
4326 tree src = TREE_OPERAND (value, 0);
4327 tree src_type = TREE_TYPE (src);
4328 tree dest_type = TREE_TYPE (value);
4330 /* Allow view-conversions from aggregate to non-aggregate type only
4331 if the bit pattern is fully preserved afterwards; otherwise, the
4332 RTL expander won't be able to apply a subsequent transformation
4333 to the underlying constructor. */
4334 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4336 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4337 return initializer_constant_valid_p_1 (src, endtype, cache);
4338 else
4339 return NULL_TREE;
4342 /* Allow all other kinds of view-conversion. */
4343 return initializer_constant_valid_p_1 (src, endtype, cache);
4346 CASE_CONVERT:
4348 tree src = TREE_OPERAND (value, 0);
4349 tree src_type = TREE_TYPE (src);
4350 tree dest_type = TREE_TYPE (value);
4352 /* Allow conversions between pointer types, floating-point
4353 types, and offset types. */
4354 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4355 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4356 || (TREE_CODE (dest_type) == OFFSET_TYPE
4357 && TREE_CODE (src_type) == OFFSET_TYPE))
4358 return initializer_constant_valid_p_1 (src, endtype, cache);
4360 /* Allow length-preserving conversions between integer types. */
4361 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4362 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4363 return initializer_constant_valid_p_1 (src, endtype, cache);
4365 /* Allow conversions between other integer types only if
4366 explicit value. */
4367 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type))
4369 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4370 if (inner == null_pointer_node)
4371 return null_pointer_node;
4372 break;
4375 /* Allow (int) &foo provided int is as wide as a pointer. */
4376 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4377 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4378 return initializer_constant_valid_p_1 (src, endtype, cache);
4380 /* Likewise conversions from int to pointers, but also allow
4381 conversions from 0. */
4382 if ((POINTER_TYPE_P (dest_type)
4383 || TREE_CODE (dest_type) == OFFSET_TYPE)
4384 && INTEGRAL_TYPE_P (src_type))
4386 if (TREE_CODE (src) == INTEGER_CST
4387 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4388 return null_pointer_node;
4389 if (integer_zerop (src))
4390 return null_pointer_node;
4391 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4392 return initializer_constant_valid_p_1 (src, endtype, cache);
4395 /* Allow conversions to struct or union types if the value
4396 inside is okay. */
4397 if (TREE_CODE (dest_type) == RECORD_TYPE
4398 || TREE_CODE (dest_type) == UNION_TYPE)
4399 return initializer_constant_valid_p_1 (src, endtype, cache);
4401 break;
4403 case POINTER_PLUS_EXPR:
4404 case PLUS_EXPR:
4405 /* Any valid floating-point constants will have been folded by now;
4406 with -frounding-math we hit this with addition of two constants. */
4407 if (TREE_CODE (endtype) == REAL_TYPE)
4408 return NULL_TREE;
4409 if (cache && cache[0] == value)
4410 return cache[1];
4411 if (! INTEGRAL_TYPE_P (endtype)
4412 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4414 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4415 tree valid0
4416 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4417 endtype, ncache);
4418 tree valid1
4419 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4420 endtype, ncache + 2);
4421 /* If either term is absolute, use the other term's relocation. */
4422 if (valid0 == null_pointer_node)
4423 ret = valid1;
4424 else if (valid1 == null_pointer_node)
4425 ret = valid0;
4426 /* Support narrowing pointer differences. */
4427 else
4428 ret = narrowing_initializer_constant_valid_p (value, endtype,
4429 ncache);
4431 else
4432 /* Support narrowing pointer differences. */
4433 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4434 if (cache)
4436 cache[0] = value;
4437 cache[1] = ret;
4439 return ret;
4441 case MINUS_EXPR:
4442 if (TREE_CODE (endtype) == REAL_TYPE)
4443 return NULL_TREE;
4444 if (cache && cache[0] == value)
4445 return cache[1];
4446 if (! INTEGRAL_TYPE_P (endtype)
4447 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4449 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4450 tree valid0
4451 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4452 endtype, ncache);
4453 tree valid1
4454 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4455 endtype, ncache + 2);
4456 /* Win if second argument is absolute. */
4457 if (valid1 == null_pointer_node)
4458 ret = valid0;
4459 /* Win if both arguments have the same relocation.
4460 Then the value is absolute. */
4461 else if (valid0 == valid1 && valid0 != 0)
4462 ret = null_pointer_node;
4463 /* Since GCC guarantees that string constants are unique in the
4464 generated code, a subtraction between two copies of the same
4465 constant string is absolute. */
4466 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4467 && valid1 && TREE_CODE (valid1) == STRING_CST
4468 && operand_equal_p (valid0, valid1, 1))
4469 ret = null_pointer_node;
4470 /* Support narrowing differences. */
4471 else
4472 ret = narrowing_initializer_constant_valid_p (value, endtype,
4473 ncache);
4475 else
4476 /* Support narrowing differences. */
4477 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4478 if (cache)
4480 cache[0] = value;
4481 cache[1] = ret;
4483 return ret;
4485 default:
4486 break;
4489 return NULL_TREE;
4492 /* Return nonzero if VALUE is a valid constant-valued expression
4493 for use in initializing a static variable; one that can be an
4494 element of a "constant" initializer.
4496 Return null_pointer_node if the value is absolute;
4497 if it is relocatable, return the variable that determines the relocation.
4498 We assume that VALUE has been folded as much as possible;
4499 therefore, we do not need to check for such things as
4500 arithmetic-combinations of integers. */
4501 tree
4502 initializer_constant_valid_p (tree value, tree endtype)
4504 return initializer_constant_valid_p_1 (value, endtype, NULL);
4507 /* Return true if VALUE is a valid constant-valued expression
4508 for use in initializing a static bit-field; one that can be
4509 an element of a "constant" initializer. */
4511 bool
4512 initializer_constant_valid_for_bitfield_p (tree value)
4514 /* For bitfields we support integer constants or possibly nested aggregates
4515 of such. */
4516 switch (TREE_CODE (value))
4518 case CONSTRUCTOR:
4520 unsigned HOST_WIDE_INT idx;
4521 tree elt;
4523 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4524 if (!initializer_constant_valid_for_bitfield_p (elt))
4525 return false;
4526 return true;
4529 case INTEGER_CST:
4530 case REAL_CST:
4531 return true;
4533 case VIEW_CONVERT_EXPR:
4534 case NON_LVALUE_EXPR:
4535 return
4536 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4538 default:
4539 break;
4542 return false;
4545 /* output_constructor outer state of relevance in recursive calls, typically
4546 for nested aggregate bitfields. */
4548 typedef struct {
4549 unsigned int bit_offset; /* current position in ... */
4550 int byte; /* ... the outer byte buffer. */
4551 } oc_outer_state;
4553 static unsigned HOST_WIDE_INT
4554 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int,
4555 oc_outer_state *);
4557 /* Output assembler code for constant EXP, with no label.
4558 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4559 Assumes output_addressed_constants has been done on EXP already.
4561 Generate at least SIZE bytes of assembler data, padding at the end
4562 with zeros if necessary. SIZE must always be specified. The returned
4563 value is the actual number of bytes of assembler data generated, which
4564 may be bigger than SIZE if the object contains a variable length field.
4566 SIZE is important for structure constructors,
4567 since trailing members may have been omitted from the constructor.
4568 It is also important for initialization of arrays from string constants
4569 since the full length of the string constant might not be wanted.
4570 It is also needed for initialization of unions, where the initializer's
4571 type is just one member, and that may not be as long as the union.
4573 There a case in which we would fail to output exactly SIZE bytes:
4574 for a structure constructor that wants to produce more than SIZE bytes.
4575 But such constructors will never be generated for any possible input.
4577 ALIGN is the alignment of the data in bits. */
4579 static unsigned HOST_WIDE_INT
4580 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align)
4582 enum tree_code code;
4583 unsigned HOST_WIDE_INT thissize;
4585 if (size == 0 || flag_syntax_only)
4586 return size;
4588 /* See if we're trying to initialize a pointer in a non-default mode
4589 to the address of some declaration somewhere. If the target says
4590 the mode is valid for pointers, assume the target has a way of
4591 resolving it. */
4592 if (TREE_CODE (exp) == NOP_EXPR
4593 && POINTER_TYPE_P (TREE_TYPE (exp))
4594 && targetm.addr_space.valid_pointer_mode
4595 (TYPE_MODE (TREE_TYPE (exp)),
4596 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4598 tree saved_type = TREE_TYPE (exp);
4600 /* Peel off any intermediate conversions-to-pointer for valid
4601 pointer modes. */
4602 while (TREE_CODE (exp) == NOP_EXPR
4603 && POINTER_TYPE_P (TREE_TYPE (exp))
4604 && targetm.addr_space.valid_pointer_mode
4605 (TYPE_MODE (TREE_TYPE (exp)),
4606 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4607 exp = TREE_OPERAND (exp, 0);
4609 /* If what we're left with is the address of something, we can
4610 convert the address to the final type and output it that
4611 way. */
4612 if (TREE_CODE (exp) == ADDR_EXPR)
4613 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4614 /* Likewise for constant ints. */
4615 else if (TREE_CODE (exp) == INTEGER_CST)
4616 exp = wide_int_to_tree (saved_type, exp);
4620 /* Eliminate any conversions since we'll be outputting the underlying
4621 constant. */
4622 while (CONVERT_EXPR_P (exp)
4623 || TREE_CODE (exp) == NON_LVALUE_EXPR
4624 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4626 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4627 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4629 /* Make sure eliminating the conversion is really a no-op, except with
4630 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4631 union types to allow for Ada unchecked unions. */
4632 if (type_size > op_size
4633 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4634 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4635 /* Keep the conversion. */
4636 break;
4637 else
4638 exp = TREE_OPERAND (exp, 0);
4641 code = TREE_CODE (TREE_TYPE (exp));
4642 thissize = int_size_in_bytes (TREE_TYPE (exp));
4644 /* Allow a constructor with no elements for any data type.
4645 This means to fill the space with zeros. */
4646 if (TREE_CODE (exp) == CONSTRUCTOR
4647 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4649 assemble_zeros (size);
4650 return size;
4653 if (TREE_CODE (exp) == FDESC_EXPR)
4655 #ifdef ASM_OUTPUT_FDESC
4656 HOST_WIDE_INT part = tree_to_shwi (TREE_OPERAND (exp, 1));
4657 tree decl = TREE_OPERAND (exp, 0);
4658 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4659 #else
4660 gcc_unreachable ();
4661 #endif
4662 return size;
4665 /* Now output the underlying data. If we've handling the padding, return.
4666 Otherwise, break and ensure SIZE is the size written. */
4667 switch (code)
4669 case BOOLEAN_TYPE:
4670 case INTEGER_TYPE:
4671 case ENUMERAL_TYPE:
4672 case POINTER_TYPE:
4673 case REFERENCE_TYPE:
4674 case OFFSET_TYPE:
4675 case FIXED_POINT_TYPE:
4676 case NULLPTR_TYPE:
4677 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
4678 EXPAND_INITIALIZER),
4679 MIN (size, thissize), align, 0))
4680 error ("initializer for integer/fixed-point value is too complicated");
4681 break;
4683 case REAL_TYPE:
4684 if (TREE_CODE (exp) != REAL_CST)
4685 error ("initializer for floating value is not a floating constant");
4686 else
4687 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)), align);
4688 break;
4690 case COMPLEX_TYPE:
4691 output_constant (TREE_REALPART (exp), thissize / 2, align);
4692 output_constant (TREE_IMAGPART (exp), thissize / 2,
4693 min_align (align, BITS_PER_UNIT * (thissize / 2)));
4694 break;
4696 case ARRAY_TYPE:
4697 case VECTOR_TYPE:
4698 switch (TREE_CODE (exp))
4700 case CONSTRUCTOR:
4701 return output_constructor (exp, size, align, NULL);
4702 case STRING_CST:
4703 thissize
4704 = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4705 assemble_string (TREE_STRING_POINTER (exp), thissize);
4706 break;
4707 case VECTOR_CST:
4709 enum machine_mode inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4710 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4711 int elt_size = GET_MODE_SIZE (inner);
4712 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align);
4713 thissize = elt_size;
4714 for (unsigned int i = 1; i < VECTOR_CST_NELTS (exp); i++)
4716 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign);
4717 thissize += elt_size;
4719 break;
4721 default:
4722 gcc_unreachable ();
4724 break;
4726 case RECORD_TYPE:
4727 case UNION_TYPE:
4728 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4729 return output_constructor (exp, size, align, NULL);
4731 case ERROR_MARK:
4732 return 0;
4734 default:
4735 gcc_unreachable ();
4738 if (size > thissize)
4739 assemble_zeros (size - thissize);
4741 return size;
4745 /* Subroutine of output_constructor, used for computing the size of
4746 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4747 type with an unspecified upper bound. */
4749 static unsigned HOST_WIDE_INT
4750 array_size_for_constructor (tree val)
4752 tree max_index;
4753 unsigned HOST_WIDE_INT cnt;
4754 tree index, value, tmp;
4755 offset_int i;
4757 /* This code used to attempt to handle string constants that are not
4758 arrays of single-bytes, but nothing else does, so there's no point in
4759 doing it here. */
4760 if (TREE_CODE (val) == STRING_CST)
4761 return TREE_STRING_LENGTH (val);
4763 max_index = NULL_TREE;
4764 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
4766 if (TREE_CODE (index) == RANGE_EXPR)
4767 index = TREE_OPERAND (index, 1);
4768 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
4769 max_index = index;
4772 if (max_index == NULL_TREE)
4773 return 0;
4775 /* Compute the total number of array elements. */
4776 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
4777 i = wi::to_offset (max_index) - wi::to_offset (tmp) + 1;
4779 /* Multiply by the array element unit size to find number of bytes. */
4780 i *= wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
4782 gcc_assert (wi::fits_uhwi_p (i));
4783 return i.to_uhwi ();
4786 /* Other datastructures + helpers for output_constructor. */
4788 /* output_constructor local state to support interaction with helpers. */
4790 typedef struct {
4792 /* Received arguments. */
4793 tree exp; /* Constructor expression. */
4794 tree type; /* Type of constructor expression. */
4795 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */
4796 unsigned int align; /* Known initial alignment. */
4797 tree min_index; /* Lower bound if specified for an array. */
4799 /* Output processing state. */
4800 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */
4801 int byte; /* Part of a bitfield byte yet to be output. */
4802 int last_relative_index; /* Implicit or explicit index of the last
4803 array element output within a bitfield. */
4804 bool byte_buffer_in_use; /* Whether BYTE is in use. */
4806 /* Current element. */
4807 tree field; /* Current field decl in a record. */
4808 tree val; /* Current element value. */
4809 tree index; /* Current element index. */
4811 } oc_local_state;
4813 /* Helper for output_constructor. From the current LOCAL state, output a
4814 RANGE_EXPR element. */
4816 static void
4817 output_constructor_array_range (oc_local_state *local)
4819 unsigned HOST_WIDE_INT fieldsize
4820 = int_size_in_bytes (TREE_TYPE (local->type));
4822 HOST_WIDE_INT lo_index
4823 = tree_to_shwi (TREE_OPERAND (local->index, 0));
4824 HOST_WIDE_INT hi_index
4825 = tree_to_shwi (TREE_OPERAND (local->index, 1));
4826 HOST_WIDE_INT index;
4828 unsigned int align2
4829 = min_align (local->align, fieldsize * BITS_PER_UNIT);
4831 for (index = lo_index; index <= hi_index; index++)
4833 /* Output the element's initial value. */
4834 if (local->val == NULL_TREE)
4835 assemble_zeros (fieldsize);
4836 else
4837 fieldsize = output_constant (local->val, fieldsize, align2);
4839 /* Count its size. */
4840 local->total_bytes += fieldsize;
4844 /* Helper for output_constructor. From the current LOCAL state, output a
4845 field element that is not true bitfield or part of an outer one. */
4847 static void
4848 output_constructor_regular_field (oc_local_state *local)
4850 /* Field size and position. Since this structure is static, we know the
4851 positions are constant. */
4852 unsigned HOST_WIDE_INT fieldsize;
4853 HOST_WIDE_INT fieldpos;
4855 unsigned int align2;
4857 if (local->index != NULL_TREE)
4859 /* Perform the index calculation in modulo arithmetic but
4860 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
4861 but we are using an unsigned sizetype. */
4862 unsigned prec = TYPE_PRECISION (sizetype);
4863 offset_int idx = wi::sext (wi::to_offset (local->index)
4864 - wi::to_offset (local->min_index), prec);
4865 fieldpos = (idx * wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (local->val))))
4866 .to_short_addr ();
4868 else if (local->field != NULL_TREE)
4869 fieldpos = int_byte_position (local->field);
4870 else
4871 fieldpos = 0;
4873 /* Output any buffered-up bit-fields preceding this element. */
4874 if (local->byte_buffer_in_use)
4876 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4877 local->total_bytes++;
4878 local->byte_buffer_in_use = false;
4881 /* Advance to offset of this element.
4882 Note no alignment needed in an array, since that is guaranteed
4883 if each element has the proper size. */
4884 if ((local->field != NULL_TREE || local->index != NULL_TREE)
4885 && fieldpos > local->total_bytes)
4887 assemble_zeros (fieldpos - local->total_bytes);
4888 local->total_bytes = fieldpos;
4891 /* Find the alignment of this element. */
4892 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
4894 /* Determine size this element should occupy. */
4895 if (local->field)
4897 fieldsize = 0;
4899 /* If this is an array with an unspecified upper bound,
4900 the initializer determines the size. */
4901 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
4902 but we cannot do this until the deprecated support for
4903 initializing zero-length array members is removed. */
4904 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
4905 && TYPE_DOMAIN (TREE_TYPE (local->field))
4906 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field))))
4908 fieldsize = array_size_for_constructor (local->val);
4909 /* Given a non-empty initialization, this field had
4910 better be last. */
4911 gcc_assert (!fieldsize || !DECL_CHAIN (local->field));
4913 else
4914 fieldsize = tree_to_uhwi (DECL_SIZE_UNIT (local->field));
4916 else
4917 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
4919 /* Output the element's initial value. */
4920 if (local->val == NULL_TREE)
4921 assemble_zeros (fieldsize);
4922 else
4923 fieldsize = output_constant (local->val, fieldsize, align2);
4925 /* Count its size. */
4926 local->total_bytes += fieldsize;
4929 /* Helper for output_constructor. From the LOCAL state, output an element
4930 that is a true bitfield or part of an outer one. BIT_OFFSET is the offset
4931 from the start of a possibly ongoing outer byte buffer. */
4933 static void
4934 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
4936 /* Bit size of this element. */
4937 HOST_WIDE_INT ebitsize
4938 = (local->field
4939 ? tree_to_uhwi (DECL_SIZE (local->field))
4940 : tree_to_uhwi (TYPE_SIZE (TREE_TYPE (local->type))));
4942 /* Relative index of this element if this is an array component. */
4943 HOST_WIDE_INT relative_index
4944 = (!local->field
4945 ? (local->index
4946 ? (tree_to_shwi (local->index)
4947 - tree_to_shwi (local->min_index))
4948 : local->last_relative_index + 1)
4949 : 0);
4951 /* Bit position of this element from the start of the containing
4952 constructor. */
4953 HOST_WIDE_INT constructor_relative_ebitpos
4954 = (local->field
4955 ? int_bit_position (local->field)
4956 : ebitsize * relative_index);
4958 /* Bit position of this element from the start of a possibly ongoing
4959 outer byte buffer. */
4960 HOST_WIDE_INT byte_relative_ebitpos
4961 = bit_offset + constructor_relative_ebitpos;
4963 /* From the start of a possibly ongoing outer byte buffer, offsets to
4964 the first bit of this element and to the first bit past the end of
4965 this element. */
4966 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
4967 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
4969 local->last_relative_index = relative_index;
4971 if (local->val == NULL_TREE)
4972 local->val = integer_zero_node;
4974 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
4975 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
4976 local->val = TREE_OPERAND (local->val, 0);
4978 if (TREE_CODE (local->val) != INTEGER_CST
4979 && TREE_CODE (local->val) != CONSTRUCTOR)
4981 error ("invalid initial value for member %qE", DECL_NAME (local->field));
4982 return;
4985 /* If this field does not start in this (or next) byte, skip some bytes. */
4986 if (next_offset / BITS_PER_UNIT != local->total_bytes)
4988 /* Output remnant of any bit field in previous bytes. */
4989 if (local->byte_buffer_in_use)
4991 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4992 local->total_bytes++;
4993 local->byte_buffer_in_use = false;
4996 /* If still not at proper byte, advance to there. */
4997 if (next_offset / BITS_PER_UNIT != local->total_bytes)
4999 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
5000 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
5001 local->total_bytes = next_offset / BITS_PER_UNIT;
5005 /* Set up the buffer if necessary. */
5006 if (!local->byte_buffer_in_use)
5008 local->byte = 0;
5009 if (ebitsize > 0)
5010 local->byte_buffer_in_use = true;
5013 /* If this is nested constructor, recurse passing the bit offset and the
5014 pending data, then retrieve the new pending data afterwards. */
5015 if (TREE_CODE (local->val) == CONSTRUCTOR)
5017 oc_outer_state temp_state;
5018 temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5019 temp_state.byte = local->byte;
5020 local->total_bytes
5021 += output_constructor (local->val, 0, 0, &temp_state);
5022 local->byte = temp_state.byte;
5023 return;
5026 /* Otherwise, we must split the element into pieces that fall within
5027 separate bytes, and combine each byte with previous or following
5028 bit-fields. */
5029 while (next_offset < end_offset)
5031 int this_time;
5032 int shift;
5033 HOST_WIDE_INT value;
5034 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5035 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5037 /* Advance from byte to byte within this element when necessary. */
5038 while (next_byte != local->total_bytes)
5040 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5041 local->total_bytes++;
5042 local->byte = 0;
5045 /* Number of bits we can process at once (all part of the same byte). */
5046 this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5047 if (BYTES_BIG_ENDIAN)
5049 /* On big-endian machine, take the most significant bits (of the
5050 bits that are significant) first and put them into bytes from
5051 the most significant end. */
5052 shift = end_offset - next_offset - this_time;
5054 /* Don't try to take a bunch of bits that cross
5055 the word boundary in the INTEGER_CST. We can
5056 only select bits from one element. */
5057 if ((shift / HOST_BITS_PER_WIDE_INT)
5058 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5060 const int end = shift + this_time - 1;
5061 shift = end & -HOST_BITS_PER_WIDE_INT;
5062 this_time = end - shift + 1;
5065 /* Now get the bits from the appropriate constant word. */
5066 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5067 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5069 /* Get the result. This works only when:
5070 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5071 local->byte |= (((value >> shift)
5072 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5073 << (BITS_PER_UNIT - this_time - next_bit));
5075 else
5077 /* On little-endian machines, take the least significant bits of
5078 the value first and pack them starting at the least significant
5079 bits of the bytes. */
5080 shift = next_offset - byte_relative_ebitpos;
5082 /* Don't try to take a bunch of bits that cross
5083 the word boundary in the INTEGER_CST. We can
5084 only select bits from one element. */
5085 if ((shift / HOST_BITS_PER_WIDE_INT)
5086 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5087 this_time
5088 = HOST_BITS_PER_WIDE_INT - (shift & (HOST_BITS_PER_WIDE_INT - 1));
5090 /* Now get the bits from the appropriate constant word. */
5091 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5092 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5094 /* Get the result. This works only when:
5095 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5096 local->byte |= (((value >> shift)
5097 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5098 << next_bit);
5101 next_offset += this_time;
5102 local->byte_buffer_in_use = true;
5106 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5107 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5108 caller output state of relevance in recursive invocations. */
5110 static unsigned HOST_WIDE_INT
5111 output_constructor (tree exp, unsigned HOST_WIDE_INT size,
5112 unsigned int align, oc_outer_state *outer)
5114 unsigned HOST_WIDE_INT cnt;
5115 constructor_elt *ce;
5117 oc_local_state local;
5119 /* Setup our local state to communicate with helpers. */
5120 local.exp = exp;
5121 local.type = TREE_TYPE (exp);
5122 local.size = size;
5123 local.align = align;
5124 if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5125 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5126 else
5127 local.min_index = NULL_TREE;
5129 local.total_bytes = 0;
5130 local.byte_buffer_in_use = outer != NULL;
5131 local.byte = outer ? outer->byte : 0;
5132 local.last_relative_index = -1;
5134 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5136 /* As CE goes through the elements of the constant, FIELD goes through the
5137 structure fields if the constant is a structure. If the constant is a
5138 union, we override this by getting the field from the TREE_LIST element.
5139 But the constant could also be an array. Then FIELD is zero.
5141 There is always a maximum of one element in the chain LINK for unions
5142 (even if the initializer in a source program incorrectly contains
5143 more one). */
5145 if (TREE_CODE (local.type) == RECORD_TYPE)
5146 local.field = TYPE_FIELDS (local.type);
5147 else
5148 local.field = NULL_TREE;
5150 for (cnt = 0;
5151 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5152 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5154 local.val = ce->value;
5155 local.index = NULL_TREE;
5157 /* The element in a union constructor specifies the proper field
5158 or index. */
5159 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5160 local.field = ce->index;
5162 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5163 local.index = ce->index;
5165 if (local.field && flag_verbose_asm)
5166 fprintf (asm_out_file, "%s %s:\n",
5167 ASM_COMMENT_START,
5168 DECL_NAME (local.field)
5169 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5170 : "<anonymous>");
5172 /* Eliminate the marker that makes a cast not be an lvalue. */
5173 if (local.val != NULL_TREE)
5174 STRIP_NOPS (local.val);
5176 /* Output the current element, using the appropriate helper ... */
5178 /* For an array slice not part of an outer bitfield. */
5179 if (!outer
5180 && local.index != NULL_TREE
5181 && TREE_CODE (local.index) == RANGE_EXPR)
5182 output_constructor_array_range (&local);
5184 /* For a field that is neither a true bitfield nor part of an outer one,
5185 known to be at least byte aligned and multiple-of-bytes long. */
5186 else if (!outer
5187 && (local.field == NULL_TREE
5188 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5189 output_constructor_regular_field (&local);
5191 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5192 supported for scalar fields, so we may need to convert first. */
5193 else
5195 if (TREE_CODE (local.val) == REAL_CST)
5196 local.val
5197 = fold_unary (VIEW_CONVERT_EXPR,
5198 build_nonstandard_integer_type
5199 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5200 local.val);
5201 output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5205 /* If we are not at toplevel, save the pending data for our caller.
5206 Otherwise output the pending data and padding zeros as needed. */
5207 if (outer)
5208 outer->byte = local.byte;
5209 else
5211 if (local.byte_buffer_in_use)
5213 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5214 local.total_bytes++;
5217 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5219 assemble_zeros (local.size - local.total_bytes);
5220 local.total_bytes = local.size;
5224 return local.total_bytes;
5227 /* Mark DECL as weak. */
5229 static void
5230 mark_weak (tree decl)
5232 if (DECL_WEAK (decl))
5233 return;
5235 struct symtab_node *n = symtab_node::get (decl);
5236 if (n && n->refuse_visibility_changes)
5237 error ("%+D declared weak after being used", decl);
5238 DECL_WEAK (decl) = 1;
5240 if (DECL_RTL_SET_P (decl)
5241 && MEM_P (DECL_RTL (decl))
5242 && XEXP (DECL_RTL (decl), 0)
5243 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5244 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5247 /* Merge weak status between NEWDECL and OLDDECL. */
5249 void
5250 merge_weak (tree newdecl, tree olddecl)
5252 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5254 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5256 tree *pwd;
5257 /* We put the NEWDECL on the weak_decls list at some point
5258 and OLDDECL as well. Keep just OLDDECL on the list. */
5259 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5260 if (TREE_VALUE (*pwd) == newdecl)
5262 *pwd = TREE_CHAIN (*pwd);
5263 break;
5266 return;
5269 if (DECL_WEAK (newdecl))
5271 tree wd;
5273 /* NEWDECL is weak, but OLDDECL is not. */
5275 /* If we already output the OLDDECL, we're in trouble; we can't
5276 go back and make it weak. This should never happen in
5277 unit-at-a-time compilation. */
5278 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5280 /* If we've already generated rtl referencing OLDDECL, we may
5281 have done so in a way that will not function properly with
5282 a weak symbol. Again in unit-at-a-time this should be
5283 impossible. */
5284 gcc_assert (!TREE_USED (olddecl)
5285 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5287 if (TARGET_SUPPORTS_WEAK)
5289 /* We put the NEWDECL on the weak_decls list at some point.
5290 Replace it with the OLDDECL. */
5291 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5292 if (TREE_VALUE (wd) == newdecl)
5294 TREE_VALUE (wd) = olddecl;
5295 break;
5297 /* We may not find the entry on the list. If NEWDECL is a
5298 weak alias, then we will have already called
5299 globalize_decl to remove the entry; in that case, we do
5300 not need to do anything. */
5303 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5304 mark_weak (olddecl);
5306 else
5307 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5308 weak. Just update NEWDECL to indicate that it's weak too. */
5309 mark_weak (newdecl);
5312 /* Declare DECL to be a weak symbol. */
5314 void
5315 declare_weak (tree decl)
5317 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5318 if (! TREE_PUBLIC (decl))
5319 error ("weak declaration of %q+D must be public", decl);
5320 else if (!TARGET_SUPPORTS_WEAK)
5321 warning (0, "weak declaration of %q+D not supported", decl);
5323 mark_weak (decl);
5324 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5325 DECL_ATTRIBUTES (decl)
5326 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5329 static void
5330 weak_finish_1 (tree decl)
5332 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5333 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5334 #endif
5336 if (! TREE_USED (decl))
5337 return;
5339 #ifdef ASM_WEAKEN_DECL
5340 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5341 #else
5342 #ifdef ASM_WEAKEN_LABEL
5343 ASM_WEAKEN_LABEL (asm_out_file, name);
5344 #else
5345 #ifdef ASM_OUTPUT_WEAK_ALIAS
5347 static bool warn_once = 0;
5348 if (! warn_once)
5350 warning (0, "only weak aliases are supported in this configuration");
5351 warn_once = 1;
5353 return;
5355 #endif
5356 #endif
5357 #endif
5360 /* Fiven an assembly name, find the decl it is associated with. */
5361 static tree
5362 find_decl (tree target)
5364 symtab_node *node = symtab_node::get_for_asmname (target);
5365 if (node)
5366 return node->decl;
5367 return NULL_TREE;
5370 /* This TREE_LIST contains weakref targets. */
5372 static GTY(()) tree weakref_targets;
5374 /* Emit any pending weak declarations. */
5376 void
5377 weak_finish (void)
5379 tree t;
5381 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5383 tree alias_decl = TREE_PURPOSE (t);
5384 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5386 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5387 /* Remove alias_decl from the weak list, but leave entries for
5388 the target alone. */
5389 target = NULL_TREE;
5390 #ifndef ASM_OUTPUT_WEAKREF
5391 else if (! TREE_SYMBOL_REFERENCED (target))
5393 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5394 defined, otherwise we and weak_finish_1 would use
5395 different macros. */
5396 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5397 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5398 # else
5399 tree decl = find_decl (target);
5401 if (! decl)
5403 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5404 TREE_CODE (alias_decl), target,
5405 TREE_TYPE (alias_decl));
5407 DECL_EXTERNAL (decl) = 1;
5408 TREE_PUBLIC (decl) = 1;
5409 DECL_ARTIFICIAL (decl) = 1;
5410 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5411 TREE_USED (decl) = 1;
5414 weak_finish_1 (decl);
5415 # endif
5417 #endif
5420 tree *p;
5421 tree t2;
5423 /* Remove the alias and the target from the pending weak list
5424 so that we do not emit any .weak directives for the former,
5425 nor multiple .weak directives for the latter. */
5426 for (p = &weak_decls; (t2 = *p) ; )
5428 if (TREE_VALUE (t2) == alias_decl
5429 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5430 *p = TREE_CHAIN (t2);
5431 else
5432 p = &TREE_CHAIN (t2);
5435 /* Remove other weakrefs to the same target, to speed things up. */
5436 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5438 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5439 *p = TREE_CHAIN (t2);
5440 else
5441 p = &TREE_CHAIN (t2);
5446 for (t = weak_decls; t; t = TREE_CHAIN (t))
5448 tree decl = TREE_VALUE (t);
5450 weak_finish_1 (decl);
5454 /* Emit the assembly bits to indicate that DECL is globally visible. */
5456 static void
5457 globalize_decl (tree decl)
5460 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5461 if (DECL_WEAK (decl))
5463 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5464 tree *p, t;
5466 #ifdef ASM_WEAKEN_DECL
5467 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5468 #else
5469 ASM_WEAKEN_LABEL (asm_out_file, name);
5470 #endif
5472 /* Remove this function from the pending weak list so that
5473 we do not emit multiple .weak directives for it. */
5474 for (p = &weak_decls; (t = *p) ; )
5476 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5477 *p = TREE_CHAIN (t);
5478 else
5479 p = &TREE_CHAIN (t);
5482 /* Remove weakrefs to the same target from the pending weakref
5483 list, for the same reason. */
5484 for (p = &weakref_targets; (t = *p) ; )
5486 if (DECL_ASSEMBLER_NAME (decl)
5487 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5488 *p = TREE_CHAIN (t);
5489 else
5490 p = &TREE_CHAIN (t);
5493 return;
5495 #endif
5497 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5500 vec<alias_pair, va_gc> *alias_pairs;
5502 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5503 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5504 tree node is DECL to have the value of the tree node TARGET. */
5506 void
5507 do_assemble_alias (tree decl, tree target)
5509 /* Emulated TLS had better not get this var. */
5510 gcc_assert (!(!targetm.have_tls
5511 && TREE_CODE (decl) == VAR_DECL
5512 && DECL_THREAD_LOCAL_P (decl)));
5514 if (TREE_ASM_WRITTEN (decl))
5515 return;
5517 /* We must force creation of DECL_RTL for debug info generation, even though
5518 we don't use it here. */
5519 make_decl_rtl (decl);
5521 TREE_ASM_WRITTEN (decl) = 1;
5522 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5524 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5526 ultimate_transparent_alias_target (&target);
5528 if (!TREE_SYMBOL_REFERENCED (target))
5529 weakref_targets = tree_cons (decl, target, weakref_targets);
5531 #ifdef ASM_OUTPUT_WEAKREF
5532 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5533 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5534 IDENTIFIER_POINTER (target));
5535 #else
5536 if (!TARGET_SUPPORTS_WEAK)
5538 error_at (DECL_SOURCE_LOCATION (decl),
5539 "weakref is not supported in this configuration");
5540 return;
5542 #endif
5543 return;
5546 #ifdef ASM_OUTPUT_DEF
5547 /* Make name accessible from other files, if appropriate. */
5549 if (TREE_PUBLIC (decl))
5551 globalize_decl (decl);
5552 maybe_assemble_visibility (decl);
5554 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5556 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5557 if (targetm.has_ifunc_p ())
5558 ASM_OUTPUT_TYPE_DIRECTIVE
5559 (asm_out_file, IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5560 IFUNC_ASM_TYPE);
5561 else
5562 #endif
5563 error_at (DECL_SOURCE_LOCATION (decl),
5564 "ifunc is not supported on this target");
5567 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5568 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5569 # else
5570 ASM_OUTPUT_DEF (asm_out_file,
5571 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5572 IDENTIFIER_POINTER (target));
5573 # endif
5574 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5576 const char *name;
5577 tree *p, t;
5579 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5580 # ifdef ASM_WEAKEN_DECL
5581 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5582 # else
5583 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5584 # endif
5585 /* Remove this function from the pending weak list so that
5586 we do not emit multiple .weak directives for it. */
5587 for (p = &weak_decls; (t = *p) ; )
5588 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5589 *p = TREE_CHAIN (t);
5590 else
5591 p = &TREE_CHAIN (t);
5593 /* Remove weakrefs to the same target from the pending weakref
5594 list, for the same reason. */
5595 for (p = &weakref_targets; (t = *p) ; )
5597 if (DECL_ASSEMBLER_NAME (decl)
5598 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5599 *p = TREE_CHAIN (t);
5600 else
5601 p = &TREE_CHAIN (t);
5604 #endif
5607 /* Emit an assembler directive to make the symbol for DECL an alias to
5608 the symbol for TARGET. */
5610 void
5611 assemble_alias (tree decl, tree target)
5613 tree target_decl;
5615 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5617 tree alias = DECL_ASSEMBLER_NAME (decl);
5619 ultimate_transparent_alias_target (&target);
5621 if (alias == target)
5622 error ("weakref %q+D ultimately targets itself", decl);
5623 if (TREE_PUBLIC (decl))
5624 error ("weakref %q+D must have static linkage", decl);
5626 else
5628 #if !defined (ASM_OUTPUT_DEF)
5629 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5630 error_at (DECL_SOURCE_LOCATION (decl),
5631 "alias definitions not supported in this configuration");
5632 TREE_ASM_WRITTEN (decl) = 1;
5633 return;
5634 # else
5635 if (!DECL_WEAK (decl))
5637 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5638 error_at (DECL_SOURCE_LOCATION (decl),
5639 "ifunc is not supported in this configuration");
5640 else
5641 error_at (DECL_SOURCE_LOCATION (decl),
5642 "only weak aliases are supported in this configuration");
5643 TREE_ASM_WRITTEN (decl) = 1;
5644 return;
5646 # endif
5647 #endif
5649 TREE_USED (decl) = 1;
5651 /* Allow aliases to aliases. */
5652 if (TREE_CODE (decl) == FUNCTION_DECL)
5653 cgraph_node::get_create (decl)->alias = true;
5654 else
5655 varpool_node::get_create (decl)->alias = true;
5657 /* If the target has already been emitted, we don't have to queue the
5658 alias. This saves a tad of memory. */
5659 if (symtab->global_info_ready)
5660 target_decl = find_decl (target);
5661 else
5662 target_decl= NULL;
5663 if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5664 || symtab->state >= EXPANSION)
5665 do_assemble_alias (decl, target);
5666 else
5668 alias_pair p = {decl, target};
5669 vec_safe_push (alias_pairs, p);
5673 /* Record and output a table of translations from original function
5674 to its transaction aware clone. Note that tm_pure functions are
5675 considered to be their own clone. */
5677 static GTY((if_marked ("tree_map_marked_p"), param_is (struct tree_map)))
5678 htab_t tm_clone_hash;
5680 void
5681 record_tm_clone_pair (tree o, tree n)
5683 struct tree_map **slot, *h;
5685 if (tm_clone_hash == NULL)
5686 tm_clone_hash = htab_create_ggc (32, tree_map_hash, tree_map_eq, 0);
5688 h = ggc_alloc<tree_map> ();
5689 h->hash = htab_hash_pointer (o);
5690 h->base.from = o;
5691 h->to = n;
5693 slot = (struct tree_map **)
5694 htab_find_slot_with_hash (tm_clone_hash, h, h->hash, INSERT);
5695 *slot = h;
5698 tree
5699 get_tm_clone_pair (tree o)
5701 if (tm_clone_hash)
5703 struct tree_map *h, in;
5705 in.base.from = o;
5706 in.hash = htab_hash_pointer (o);
5707 h = (struct tree_map *) htab_find_with_hash (tm_clone_hash,
5708 &in, in.hash);
5709 if (h)
5710 return h->to;
5712 return NULL_TREE;
5715 typedef struct tm_alias_pair
5717 unsigned int uid;
5718 tree from;
5719 tree to;
5720 } tm_alias_pair;
5723 /* Helper function for finish_tm_clone_pairs. Dump a hash table entry
5724 into a VEC in INFO. */
5726 static int
5727 dump_tm_clone_to_vec (void **slot, void *info)
5729 struct tree_map *map = (struct tree_map *) *slot;
5730 vec<tm_alias_pair> *tm_alias_pairs = (vec<tm_alias_pair> *) info;
5731 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
5732 tm_alias_pairs->safe_push (p);
5733 return 1;
5736 /* Dump the actual pairs to the .tm_clone_table section. */
5738 static void
5739 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
5741 unsigned i;
5742 tm_alias_pair *p;
5743 bool switched = false;
5745 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
5747 tree src = p->from;
5748 tree dst = p->to;
5749 struct cgraph_node *src_n = cgraph_node::get (src);
5750 struct cgraph_node *dst_n = cgraph_node::get (dst);
5752 /* The function ipa_tm_create_version() marks the clone as needed if
5753 the original function was needed. But we also mark the clone as
5754 needed if we ever called the clone indirectly through
5755 TM_GETTMCLONE. If neither of these are true, we didn't generate
5756 a clone, and we didn't call it indirectly... no sense keeping it
5757 in the clone table. */
5758 if (!dst_n || !dst_n->definition)
5759 continue;
5761 /* This covers the case where we have optimized the original
5762 function away, and only access the transactional clone. */
5763 if (!src_n || !src_n->definition)
5764 continue;
5766 if (!switched)
5768 switch_to_section (targetm.asm_out.tm_clone_table_section ());
5769 assemble_align (POINTER_SIZE);
5770 switched = true;
5773 assemble_integer (XEXP (DECL_RTL (src), 0),
5774 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
5775 assemble_integer (XEXP (DECL_RTL (dst), 0),
5776 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
5780 /* Provide a default for the tm_clone_table section. */
5782 section *
5783 default_clone_table_section (void)
5785 return get_named_section (NULL, ".tm_clone_table", 3);
5788 /* Helper comparison function for qsorting by the DECL_UID stored in
5789 alias_pair->emitted_diags. */
5791 static int
5792 tm_alias_pair_cmp (const void *x, const void *y)
5794 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
5795 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
5796 if (p1->uid < p2->uid)
5797 return -1;
5798 if (p1->uid > p2->uid)
5799 return 1;
5800 return 0;
5803 void
5804 finish_tm_clone_pairs (void)
5806 vec<tm_alias_pair> tm_alias_pairs = vNULL;
5808 if (tm_clone_hash == NULL)
5809 return;
5811 /* We need a determenistic order for the .tm_clone_table, otherwise
5812 we will get bootstrap comparison failures, so dump the hash table
5813 to a vector, sort it, and dump the vector. */
5815 /* Dump the hashtable to a vector. */
5816 htab_traverse_noresize (tm_clone_hash, dump_tm_clone_to_vec,
5817 (void *) &tm_alias_pairs);
5818 /* Sort it. */
5819 tm_alias_pairs.qsort (tm_alias_pair_cmp);
5821 /* Dump it. */
5822 dump_tm_clone_pairs (tm_alias_pairs);
5824 htab_delete (tm_clone_hash);
5825 tm_clone_hash = NULL;
5826 tm_alias_pairs.release ();
5830 /* Emit an assembler directive to set symbol for DECL visibility to
5831 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
5833 void
5834 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
5835 int vis ATTRIBUTE_UNUSED)
5837 #ifdef HAVE_GAS_HIDDEN
5838 static const char * const visibility_types[] = {
5839 NULL, "protected", "hidden", "internal"
5842 const char *name, *type;
5844 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5845 type = visibility_types[vis];
5847 fprintf (asm_out_file, "\t.%s\t", type);
5848 assemble_name (asm_out_file, name);
5849 fprintf (asm_out_file, "\n");
5850 #else
5851 if (!DECL_ARTIFICIAL (decl))
5852 warning (OPT_Wattributes, "visibility attribute not supported "
5853 "in this configuration; ignored");
5854 #endif
5857 /* A helper function to call assemble_visibility when needed for a decl. */
5860 maybe_assemble_visibility (tree decl)
5862 enum symbol_visibility vis = DECL_VISIBILITY (decl);
5864 if (vis != VISIBILITY_DEFAULT)
5866 targetm.asm_out.assemble_visibility (decl, vis);
5867 return 1;
5869 else
5870 return 0;
5873 /* Returns 1 if the target configuration supports defining public symbols
5874 so that one of them will be chosen at link time instead of generating a
5875 multiply-defined symbol error, whether through the use of weak symbols or
5876 a target-specific mechanism for having duplicates discarded. */
5879 supports_one_only (void)
5881 if (SUPPORTS_ONE_ONLY)
5882 return 1;
5883 return TARGET_SUPPORTS_WEAK;
5886 /* Set up DECL as a public symbol that can be defined in multiple
5887 translation units without generating a linker error. */
5889 void
5890 make_decl_one_only (tree decl, tree comdat_group)
5892 struct symtab_node *symbol;
5893 gcc_assert (TREE_CODE (decl) == VAR_DECL
5894 || TREE_CODE (decl) == FUNCTION_DECL);
5896 TREE_PUBLIC (decl) = 1;
5898 if (TREE_CODE (decl) == VAR_DECL)
5899 symbol = varpool_node::get_create (decl);
5900 else
5901 symbol = cgraph_node::get_create (decl);
5903 if (SUPPORTS_ONE_ONLY)
5905 #ifdef MAKE_DECL_ONE_ONLY
5906 MAKE_DECL_ONE_ONLY (decl);
5907 #endif
5908 symbol->set_comdat_group (comdat_group);
5910 else if (TREE_CODE (decl) == VAR_DECL
5911 && (DECL_INITIAL (decl) == 0
5912 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
5913 DECL_COMMON (decl) = 1;
5914 else
5916 gcc_assert (TARGET_SUPPORTS_WEAK);
5917 DECL_WEAK (decl) = 1;
5921 void
5922 init_varasm_once (void)
5924 section_htab = hash_table<section_hasher>::create_ggc (31);
5925 object_block_htab = hash_table<object_block_hasher>::create_ggc (31);
5926 const_desc_htab = hash_table<tree_descriptor_hasher>::create_ggc (1009);
5928 const_alias_set = new_alias_set ();
5929 shared_constant_pool = create_constant_pool ();
5931 #ifdef TEXT_SECTION_ASM_OP
5932 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
5933 TEXT_SECTION_ASM_OP);
5934 #endif
5936 #ifdef DATA_SECTION_ASM_OP
5937 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5938 DATA_SECTION_ASM_OP);
5939 #endif
5941 #ifdef SDATA_SECTION_ASM_OP
5942 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5943 SDATA_SECTION_ASM_OP);
5944 #endif
5946 #ifdef READONLY_DATA_SECTION_ASM_OP
5947 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
5948 READONLY_DATA_SECTION_ASM_OP);
5949 #endif
5951 #ifdef CTORS_SECTION_ASM_OP
5952 ctors_section = get_unnamed_section (0, output_section_asm_op,
5953 CTORS_SECTION_ASM_OP);
5954 #endif
5956 #ifdef DTORS_SECTION_ASM_OP
5957 dtors_section = get_unnamed_section (0, output_section_asm_op,
5958 DTORS_SECTION_ASM_OP);
5959 #endif
5961 #ifdef BSS_SECTION_ASM_OP
5962 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5963 output_section_asm_op,
5964 BSS_SECTION_ASM_OP);
5965 #endif
5967 #ifdef SBSS_SECTION_ASM_OP
5968 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5969 output_section_asm_op,
5970 SBSS_SECTION_ASM_OP);
5971 #endif
5973 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5974 | SECTION_COMMON, emit_tls_common);
5975 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5976 | SECTION_COMMON, emit_local);
5977 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5978 | SECTION_COMMON, emit_common);
5980 #if defined ASM_OUTPUT_ALIGNED_BSS
5981 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
5982 emit_bss);
5983 #endif
5985 targetm.asm_out.init_sections ();
5987 if (readonly_data_section == NULL)
5988 readonly_data_section = text_section;
5990 #ifdef ASM_OUTPUT_EXTERNAL
5991 pending_assemble_externals_set = new hash_set<tree>;
5992 #endif
5995 enum tls_model
5996 decl_default_tls_model (const_tree decl)
5998 enum tls_model kind;
5999 bool is_local;
6001 is_local = targetm.binds_local_p (decl);
6002 if (!flag_shlib)
6004 if (is_local)
6005 kind = TLS_MODEL_LOCAL_EXEC;
6006 else
6007 kind = TLS_MODEL_INITIAL_EXEC;
6010 /* Local dynamic is inefficient when we're not combining the
6011 parts of the address. */
6012 else if (optimize && is_local)
6013 kind = TLS_MODEL_LOCAL_DYNAMIC;
6014 else
6015 kind = TLS_MODEL_GLOBAL_DYNAMIC;
6016 if (kind < flag_tls_default)
6017 kind = flag_tls_default;
6019 return kind;
6022 /* Select a set of attributes for section NAME based on the properties
6023 of DECL and whether or not RELOC indicates that DECL's initializer
6024 might contain runtime relocations.
6026 We make the section read-only and executable for a function decl,
6027 read-only for a const data decl, and writable for a non-const data decl. */
6029 unsigned int
6030 default_section_type_flags (tree decl, const char *name, int reloc)
6032 unsigned int flags;
6034 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6035 flags = SECTION_CODE;
6036 else if (decl)
6038 enum section_category category
6039 = categorize_decl_for_section (decl, reloc);
6040 if (decl_readonly_section_1 (category))
6041 flags = 0;
6042 else if (category == SECCAT_DATA_REL_RO
6043 || category == SECCAT_DATA_REL_RO_LOCAL)
6044 flags = SECTION_WRITE | SECTION_RELRO;
6045 else
6046 flags = SECTION_WRITE;
6048 else
6050 flags = SECTION_WRITE;
6051 if (strcmp (name, ".data.rel.ro") == 0
6052 || strcmp (name, ".data.rel.ro.local") == 0)
6053 flags |= SECTION_RELRO;
6056 if (decl && DECL_P (decl) && DECL_COMDAT_GROUP (decl))
6057 flags |= SECTION_LINKONCE;
6059 if (strcmp (name, ".vtable_map_vars") == 0)
6060 flags |= SECTION_LINKONCE;
6062 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6063 flags |= SECTION_TLS | SECTION_WRITE;
6065 if (strcmp (name, ".bss") == 0
6066 || strncmp (name, ".bss.", 5) == 0
6067 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6068 || strcmp (name, ".persistent.bss") == 0
6069 || strcmp (name, ".sbss") == 0
6070 || strncmp (name, ".sbss.", 6) == 0
6071 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6072 flags |= SECTION_BSS;
6074 if (strcmp (name, ".tdata") == 0
6075 || strncmp (name, ".tdata.", 7) == 0
6076 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6077 flags |= SECTION_TLS;
6079 if (strcmp (name, ".tbss") == 0
6080 || strncmp (name, ".tbss.", 6) == 0
6081 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6082 flags |= SECTION_TLS | SECTION_BSS;
6084 /* These three sections have special ELF types. They are neither
6085 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
6086 want to print a section type (@progbits or @nobits). If someone
6087 is silly enough to emit code or TLS variables to one of these
6088 sections, then don't handle them specially. */
6089 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6090 && (strcmp (name, ".init_array") == 0
6091 || strcmp (name, ".fini_array") == 0
6092 || strcmp (name, ".preinit_array") == 0))
6093 flags |= SECTION_NOTYPE;
6095 return flags;
6098 /* Return true if the target supports some form of global BSS,
6099 either through bss_noswitch_section, or by selecting a BSS
6100 section in TARGET_ASM_SELECT_SECTION. */
6102 bool
6103 have_global_bss_p (void)
6105 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6108 /* Output assembly to switch to section NAME with attribute FLAGS.
6109 Four variants for common object file formats. */
6111 void
6112 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6113 unsigned int flags ATTRIBUTE_UNUSED,
6114 tree decl ATTRIBUTE_UNUSED)
6116 /* Some object formats don't support named sections at all. The
6117 front-end should already have flagged this as an error. */
6118 gcc_unreachable ();
6121 #ifndef TLS_SECTION_ASM_FLAG
6122 #define TLS_SECTION_ASM_FLAG 'T'
6123 #endif
6125 void
6126 default_elf_asm_named_section (const char *name, unsigned int flags,
6127 tree decl ATTRIBUTE_UNUSED)
6129 char flagchars[10], *f = flagchars;
6131 /* If we have already declared this section, we can use an
6132 abbreviated form to switch back to it -- unless this section is
6133 part of a COMDAT groups, in which case GAS requires the full
6134 declaration every time. */
6135 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6136 && (flags & SECTION_DECLARED))
6138 fprintf (asm_out_file, "\t.section\t%s\n", name);
6139 return;
6142 if (!(flags & SECTION_DEBUG))
6143 *f++ = 'a';
6144 if (flags & SECTION_EXCLUDE)
6145 *f++ = 'e';
6146 if (flags & SECTION_WRITE)
6147 *f++ = 'w';
6148 if (flags & SECTION_CODE)
6149 *f++ = 'x';
6150 if (flags & SECTION_SMALL)
6151 *f++ = 's';
6152 if (flags & SECTION_MERGE)
6153 *f++ = 'M';
6154 if (flags & SECTION_STRINGS)
6155 *f++ = 'S';
6156 if (flags & SECTION_TLS)
6157 *f++ = TLS_SECTION_ASM_FLAG;
6158 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6159 *f++ = 'G';
6160 *f = '\0';
6162 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6164 if (!(flags & SECTION_NOTYPE))
6166 const char *type;
6167 const char *format;
6169 if (flags & SECTION_BSS)
6170 type = "nobits";
6171 else
6172 type = "progbits";
6174 format = ",@%s";
6175 /* On platforms that use "@" as the assembly comment character,
6176 use "%" instead. */
6177 if (strcmp (ASM_COMMENT_START, "@") == 0)
6178 format = ",%%%s";
6179 fprintf (asm_out_file, format, type);
6181 if (flags & SECTION_ENTSIZE)
6182 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6183 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6185 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6186 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6187 else
6188 fprintf (asm_out_file, ",%s,comdat",
6189 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6193 putc ('\n', asm_out_file);
6196 void
6197 default_coff_asm_named_section (const char *name, unsigned int flags,
6198 tree decl ATTRIBUTE_UNUSED)
6200 char flagchars[8], *f = flagchars;
6202 if (flags & SECTION_WRITE)
6203 *f++ = 'w';
6204 if (flags & SECTION_CODE)
6205 *f++ = 'x';
6206 *f = '\0';
6208 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6211 void
6212 default_pe_asm_named_section (const char *name, unsigned int flags,
6213 tree decl)
6215 default_coff_asm_named_section (name, flags, decl);
6217 if (flags & SECTION_LINKONCE)
6219 /* Functions may have been compiled at various levels of
6220 optimization so we can't use `same_size' here.
6221 Instead, have the linker pick one. */
6222 fprintf (asm_out_file, "\t.linkonce %s\n",
6223 (flags & SECTION_CODE ? "discard" : "same_size"));
6227 /* The lame default section selector. */
6229 section *
6230 default_select_section (tree decl, int reloc,
6231 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6233 if (DECL_P (decl))
6235 if (decl_readonly_section (decl, reloc))
6236 return readonly_data_section;
6238 else if (TREE_CODE (decl) == CONSTRUCTOR)
6240 if (! ((flag_pic && reloc)
6241 || !TREE_READONLY (decl)
6242 || TREE_SIDE_EFFECTS (decl)
6243 || !TREE_CONSTANT (decl)))
6244 return readonly_data_section;
6246 else if (TREE_CODE (decl) == STRING_CST)
6247 return readonly_data_section;
6248 else if (! (flag_pic && reloc))
6249 return readonly_data_section;
6251 return data_section;
6254 enum section_category
6255 categorize_decl_for_section (const_tree decl, int reloc)
6257 enum section_category ret;
6259 if (TREE_CODE (decl) == FUNCTION_DECL)
6260 return SECCAT_TEXT;
6261 else if (TREE_CODE (decl) == STRING_CST)
6263 if ((flag_sanitize & SANITIZE_ADDRESS)
6264 && asan_protect_global (CONST_CAST_TREE (decl)))
6265 /* or !flag_merge_constants */
6266 return SECCAT_RODATA;
6267 else
6268 return SECCAT_RODATA_MERGE_STR;
6270 else if (TREE_CODE (decl) == VAR_DECL)
6272 if (bss_initializer_p (decl))
6273 ret = SECCAT_BSS;
6274 else if (! TREE_READONLY (decl)
6275 || TREE_SIDE_EFFECTS (decl)
6276 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
6278 /* Here the reloc_rw_mask is not testing whether the section should
6279 be read-only or not, but whether the dynamic link will have to
6280 do something. If so, we wish to segregate the data in order to
6281 minimize cache misses inside the dynamic linker. */
6282 if (reloc & targetm.asm_out.reloc_rw_mask ())
6283 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6284 else
6285 ret = SECCAT_DATA;
6287 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6288 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6289 else if (reloc || flag_merge_constants < 2
6290 || ((flag_sanitize & SANITIZE_ADDRESS)
6291 && asan_protect_global (CONST_CAST_TREE (decl))))
6292 /* C and C++ don't allow different variables to share the same
6293 location. -fmerge-all-constants allows even that (at the
6294 expense of not conforming). */
6295 ret = SECCAT_RODATA;
6296 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6297 ret = SECCAT_RODATA_MERGE_STR_INIT;
6298 else
6299 ret = SECCAT_RODATA_MERGE_CONST;
6301 else if (TREE_CODE (decl) == CONSTRUCTOR)
6303 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6304 || TREE_SIDE_EFFECTS (decl)
6305 || ! TREE_CONSTANT (decl))
6306 ret = SECCAT_DATA;
6307 else
6308 ret = SECCAT_RODATA;
6310 else
6311 ret = SECCAT_RODATA;
6313 /* There are no read-only thread-local sections. */
6314 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6316 /* Note that this would be *just* SECCAT_BSS, except that there's
6317 no concept of a read-only thread-local-data section. */
6318 if (ret == SECCAT_BSS
6319 || (flag_zero_initialized_in_bss
6320 && initializer_zerop (DECL_INITIAL (decl))))
6321 ret = SECCAT_TBSS;
6322 else
6323 ret = SECCAT_TDATA;
6326 /* If the target uses small data sections, select it. */
6327 else if (targetm.in_small_data_p (decl))
6329 if (ret == SECCAT_BSS)
6330 ret = SECCAT_SBSS;
6331 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6332 ret = SECCAT_SRODATA;
6333 else
6334 ret = SECCAT_SDATA;
6337 return ret;
6340 static bool
6341 decl_readonly_section_1 (enum section_category category)
6343 switch (category)
6345 case SECCAT_RODATA:
6346 case SECCAT_RODATA_MERGE_STR:
6347 case SECCAT_RODATA_MERGE_STR_INIT:
6348 case SECCAT_RODATA_MERGE_CONST:
6349 case SECCAT_SRODATA:
6350 return true;
6351 default:
6352 return false;
6356 bool
6357 decl_readonly_section (const_tree decl, int reloc)
6359 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6362 /* Select a section based on the above categorization. */
6364 section *
6365 default_elf_select_section (tree decl, int reloc,
6366 unsigned HOST_WIDE_INT align)
6368 const char *sname;
6369 switch (categorize_decl_for_section (decl, reloc))
6371 case SECCAT_TEXT:
6372 /* We're not supposed to be called on FUNCTION_DECLs. */
6373 gcc_unreachable ();
6374 case SECCAT_RODATA:
6375 return readonly_data_section;
6376 case SECCAT_RODATA_MERGE_STR:
6377 return mergeable_string_section (decl, align, 0);
6378 case SECCAT_RODATA_MERGE_STR_INIT:
6379 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6380 case SECCAT_RODATA_MERGE_CONST:
6381 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6382 case SECCAT_SRODATA:
6383 sname = ".sdata2";
6384 break;
6385 case SECCAT_DATA:
6386 return data_section;
6387 case SECCAT_DATA_REL:
6388 sname = ".data.rel";
6389 break;
6390 case SECCAT_DATA_REL_LOCAL:
6391 sname = ".data.rel.local";
6392 break;
6393 case SECCAT_DATA_REL_RO:
6394 sname = ".data.rel.ro";
6395 break;
6396 case SECCAT_DATA_REL_RO_LOCAL:
6397 sname = ".data.rel.ro.local";
6398 break;
6399 case SECCAT_SDATA:
6400 sname = ".sdata";
6401 break;
6402 case SECCAT_TDATA:
6403 sname = ".tdata";
6404 break;
6405 case SECCAT_BSS:
6406 if (bss_section)
6407 return bss_section;
6408 sname = ".bss";
6409 break;
6410 case SECCAT_SBSS:
6411 sname = ".sbss";
6412 break;
6413 case SECCAT_TBSS:
6414 sname = ".tbss";
6415 break;
6416 default:
6417 gcc_unreachable ();
6420 return get_named_section (decl, sname, reloc);
6423 /* Construct a unique section name based on the decl name and the
6424 categorization performed above. */
6426 void
6427 default_unique_section (tree decl, int reloc)
6429 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6430 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6431 const char *prefix, *name, *linkonce;
6432 char *string;
6434 switch (categorize_decl_for_section (decl, reloc))
6436 case SECCAT_TEXT:
6437 prefix = one_only ? ".t" : ".text";
6438 break;
6439 case SECCAT_RODATA:
6440 case SECCAT_RODATA_MERGE_STR:
6441 case SECCAT_RODATA_MERGE_STR_INIT:
6442 case SECCAT_RODATA_MERGE_CONST:
6443 prefix = one_only ? ".r" : ".rodata";
6444 break;
6445 case SECCAT_SRODATA:
6446 prefix = one_only ? ".s2" : ".sdata2";
6447 break;
6448 case SECCAT_DATA:
6449 prefix = one_only ? ".d" : ".data";
6450 break;
6451 case SECCAT_DATA_REL:
6452 prefix = one_only ? ".d.rel" : ".data.rel";
6453 break;
6454 case SECCAT_DATA_REL_LOCAL:
6455 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6456 break;
6457 case SECCAT_DATA_REL_RO:
6458 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6459 break;
6460 case SECCAT_DATA_REL_RO_LOCAL:
6461 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6462 break;
6463 case SECCAT_SDATA:
6464 prefix = one_only ? ".s" : ".sdata";
6465 break;
6466 case SECCAT_BSS:
6467 prefix = one_only ? ".b" : ".bss";
6468 break;
6469 case SECCAT_SBSS:
6470 prefix = one_only ? ".sb" : ".sbss";
6471 break;
6472 case SECCAT_TDATA:
6473 prefix = one_only ? ".td" : ".tdata";
6474 break;
6475 case SECCAT_TBSS:
6476 prefix = one_only ? ".tb" : ".tbss";
6477 break;
6478 default:
6479 gcc_unreachable ();
6482 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
6483 name = targetm.strip_name_encoding (name);
6485 /* If we're using one_only, then there needs to be a .gnu.linkonce
6486 prefix to the section name. */
6487 linkonce = one_only ? ".gnu.linkonce" : "";
6489 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6491 set_decl_section_name (decl, string);
6494 /* Subroutine of compute_reloc_for_rtx for leaf rtxes. */
6496 static int
6497 compute_reloc_for_rtx_1 (const_rtx x)
6499 switch (GET_CODE (x))
6501 case SYMBOL_REF:
6502 return SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6503 case LABEL_REF:
6504 return 1;
6505 default:
6506 return 0;
6510 /* Like compute_reloc_for_constant, except for an RTX. The return value
6511 is a mask for which bit 1 indicates a global relocation, and bit 0
6512 indicates a local relocation. */
6514 static int
6515 compute_reloc_for_rtx (const_rtx x)
6517 switch (GET_CODE (x))
6519 case SYMBOL_REF:
6520 case LABEL_REF:
6521 return compute_reloc_for_rtx_1 (x);
6523 case CONST:
6525 int reloc = 0;
6526 subrtx_iterator::array_type array;
6527 FOR_EACH_SUBRTX (iter, array, x, ALL)
6528 reloc |= compute_reloc_for_rtx_1 (*iter);
6529 return reloc;
6532 default:
6533 return 0;
6537 section *
6538 default_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
6539 rtx x,
6540 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6542 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6543 return data_section;
6544 else
6545 return readonly_data_section;
6548 section *
6549 default_elf_select_rtx_section (enum machine_mode mode, rtx x,
6550 unsigned HOST_WIDE_INT align)
6552 int reloc = compute_reloc_for_rtx (x);
6554 /* ??? Handle small data here somehow. */
6556 if (reloc & targetm.asm_out.reloc_rw_mask ())
6558 if (reloc == 1)
6559 return get_named_section (NULL, ".data.rel.ro.local", 1);
6560 else
6561 return get_named_section (NULL, ".data.rel.ro", 3);
6564 return mergeable_constant_section (mode, align, 0);
6567 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6569 void
6570 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6572 rtx symbol;
6573 int flags;
6575 /* Careful not to prod global register variables. */
6576 if (!MEM_P (rtl))
6577 return;
6578 symbol = XEXP (rtl, 0);
6579 if (GET_CODE (symbol) != SYMBOL_REF)
6580 return;
6582 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6583 if (TREE_CODE (decl) == FUNCTION_DECL)
6584 flags |= SYMBOL_FLAG_FUNCTION;
6585 if (targetm.binds_local_p (decl))
6586 flags |= SYMBOL_FLAG_LOCAL;
6587 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6588 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6589 else if (targetm.in_small_data_p (decl))
6590 flags |= SYMBOL_FLAG_SMALL;
6591 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6592 being PUBLIC, the thing *must* be defined in this translation unit.
6593 Prevent this buglet from being propagated into rtl code as well. */
6594 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6595 flags |= SYMBOL_FLAG_EXTERNAL;
6597 SYMBOL_REF_FLAGS (symbol) = flags;
6600 /* By default, we do nothing for encode_section_info, so we need not
6601 do anything but discard the '*' marker. */
6603 const char *
6604 default_strip_name_encoding (const char *str)
6606 return str + (*str == '*');
6609 #ifdef ASM_OUTPUT_DEF
6610 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6611 anchor relative to ".", the current section position. */
6613 void
6614 default_asm_output_anchor (rtx symbol)
6616 char buffer[100];
6618 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6619 SYMBOL_REF_BLOCK_OFFSET (symbol));
6620 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6622 #endif
6624 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6626 bool
6627 default_use_anchors_for_symbol_p (const_rtx symbol)
6629 section *sect;
6630 tree decl;
6632 /* Don't use anchors for mergeable sections. The linker might move
6633 the objects around. */
6634 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6635 if (sect->common.flags & SECTION_MERGE)
6636 return false;
6638 /* Don't use anchors for small data sections. The small data register
6639 acts as an anchor for such sections. */
6640 if (sect->common.flags & SECTION_SMALL)
6641 return false;
6643 decl = SYMBOL_REF_DECL (symbol);
6644 if (decl && DECL_P (decl))
6646 /* Don't use section anchors for decls that might be defined or
6647 usurped by other modules. */
6648 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6649 return false;
6651 /* Don't use section anchors for decls that will be placed in a
6652 small data section. */
6653 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6654 one above. The problem is that we only use SECTION_SMALL for
6655 sections that should be marked as small in the section directive. */
6656 if (targetm.in_small_data_p (decl))
6657 return false;
6659 return true;
6662 /* Return true when RESOLUTION indicate that symbol will be bound to the
6663 definition provided by current .o file. */
6665 static bool
6666 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
6668 return (resolution == LDPR_PREVAILING_DEF
6669 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6670 || resolution == LDPR_PREVAILING_DEF_IRONLY);
6673 /* Return true when RESOLUTION indicate that symbol will be bound locally
6674 within current executable or DSO. */
6676 static bool
6677 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
6679 return (resolution == LDPR_PREVAILING_DEF
6680 || resolution == LDPR_PREVAILING_DEF_IRONLY
6681 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6682 || resolution == LDPR_PREEMPTED_REG
6683 || resolution == LDPR_PREEMPTED_IR
6684 || resolution == LDPR_RESOLVED_IR
6685 || resolution == LDPR_RESOLVED_EXEC);
6688 /* Assume ELF-ish defaults, since that's pretty much the most liberal
6689 wrt cross-module name binding. */
6691 bool
6692 default_binds_local_p (const_tree exp)
6694 return default_binds_local_p_1 (exp, flag_shlib);
6697 bool
6698 default_binds_local_p_1 (const_tree exp, int shlib)
6700 bool local_p;
6701 bool resolved_locally = false;
6702 bool resolved_to_local_def = false;
6704 /* With resolution file in hands, take look into resolutions.
6705 We can't just return true for resolved_locally symbols,
6706 because dynamic linking might overwrite symbols
6707 in shared libraries. */
6708 if (TREE_CODE (exp) == VAR_DECL && TREE_PUBLIC (exp)
6709 && (TREE_STATIC (exp) || DECL_EXTERNAL (exp)))
6711 varpool_node *vnode = varpool_node::get (exp);
6712 if (vnode && (resolution_local_p (vnode->resolution) || vnode->in_other_partition))
6713 resolved_locally = true;
6714 if (vnode
6715 && resolution_to_local_definition_p (vnode->resolution))
6716 resolved_to_local_def = true;
6718 else if (TREE_CODE (exp) == FUNCTION_DECL && TREE_PUBLIC (exp))
6720 struct cgraph_node *node = cgraph_node::get (exp);
6721 if (node
6722 && (resolution_local_p (node->resolution) || node->in_other_partition))
6723 resolved_locally = true;
6724 if (node
6725 && resolution_to_local_definition_p (node->resolution))
6726 resolved_to_local_def = true;
6729 /* A non-decl is an entry in the constant pool. */
6730 if (!DECL_P (exp))
6731 local_p = true;
6732 /* Weakrefs may not bind locally, even though the weakref itself is always
6733 static and therefore local. Similarly, the resolver for ifunc functions
6734 might resolve to a non-local function.
6735 FIXME: We can resolve the weakref case more curefuly by looking at the
6736 weakref alias. */
6737 else if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
6738 || (TREE_CODE (exp) == FUNCTION_DECL
6739 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
6740 local_p = false;
6741 /* Static variables are always local. */
6742 else if (! TREE_PUBLIC (exp))
6743 local_p = true;
6744 /* A variable is local if the user has said explicitly that it will
6745 be. */
6746 else if ((DECL_VISIBILITY_SPECIFIED (exp)
6747 || resolved_to_local_def)
6748 && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6749 local_p = true;
6750 /* Variables defined outside this object might not be local. */
6751 else if (DECL_EXTERNAL (exp) && !resolved_locally)
6752 local_p = false;
6753 /* If defined in this object and visibility is not default, must be
6754 local. */
6755 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6756 local_p = true;
6757 /* Default visibility weak data can be overridden by a strong symbol
6758 in another module and so are not local. */
6759 else if (DECL_WEAK (exp)
6760 && !resolved_locally)
6761 local_p = false;
6762 /* If PIC, then assume that any global name can be overridden by
6763 symbols resolved from other modules. */
6764 else if (shlib)
6765 local_p = false;
6766 /* Uninitialized COMMON variable may be unified with symbols
6767 resolved from other modules. */
6768 else if (DECL_COMMON (exp)
6769 && !resolved_locally
6770 && (DECL_INITIAL (exp) == NULL
6771 || (!in_lto_p && DECL_INITIAL (exp) == error_mark_node)))
6772 local_p = false;
6773 /* Otherwise we're left with initialized (or non-common) global data
6774 which is of necessity defined locally. */
6775 else
6776 local_p = true;
6778 return local_p;
6781 /* Return true when references to DECL must bind to current definition in
6782 final executable.
6784 The condition is usually equivalent to whether the function binds to the
6785 current module (shared library or executable), that is to binds_local_p.
6786 We use this fact to avoid need for another target hook and implement
6787 the logic using binds_local_p and just special cases where
6788 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
6789 the weak definitions (that can be overwritten at linktime by other
6790 definition from different object file) and when resolution info is available
6791 we simply use the knowledge passed to us by linker plugin. */
6792 bool
6793 decl_binds_to_current_def_p (const_tree decl)
6795 gcc_assert (DECL_P (decl));
6796 if (!targetm.binds_local_p (decl))
6797 return false;
6798 if (!TREE_PUBLIC (decl))
6799 return true;
6800 /* When resolution is available, just use it. */
6801 if (TREE_CODE (decl) == VAR_DECL
6802 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl)))
6804 varpool_node *vnode = varpool_node::get (decl);
6805 if (vnode
6806 && vnode->resolution != LDPR_UNKNOWN)
6807 return resolution_to_local_definition_p (vnode->resolution);
6809 else if (TREE_CODE (decl) == FUNCTION_DECL)
6811 struct cgraph_node *node = cgraph_node::get (decl);
6812 if (node
6813 && node->resolution != LDPR_UNKNOWN)
6814 return resolution_to_local_definition_p (node->resolution);
6816 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
6817 binds locally but still can be overwritten), DECL_COMMON (can be merged
6818 with a non-common definition somewhere in the same module) or
6819 DECL_EXTERNAL.
6820 This rely on fact that binds_local_p behave as decl_replaceable_p
6821 for all other declaration types. */
6822 if (DECL_WEAK (decl))
6823 return false;
6824 if (DECL_COMMON (decl)
6825 && (DECL_INITIAL (decl) == NULL
6826 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
6827 return false;
6828 if (DECL_EXTERNAL (decl))
6829 return false;
6830 return true;
6833 /* A replaceable function or variable is one which may be replaced
6834 at link-time with an entirely different definition, provided that the
6835 replacement has the same type. For example, functions declared
6836 with __attribute__((weak)) on most systems are replaceable.
6838 COMDAT functions are not replaceable, since all definitions of the
6839 function must be equivalent. It is important that COMDAT functions
6840 not be treated as replaceable so that use of C++ template
6841 instantiations is not penalized. */
6843 bool
6844 decl_replaceable_p (tree decl)
6846 gcc_assert (DECL_P (decl));
6847 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
6848 return false;
6849 if (!flag_semantic_interposition
6850 && !DECL_WEAK (decl))
6851 return false;
6852 return !decl_binds_to_current_def_p (decl);
6855 /* Default function to output code that will globalize a label. A
6856 target must define GLOBAL_ASM_OP or provide its own function to
6857 globalize a label. */
6858 #ifdef GLOBAL_ASM_OP
6859 void
6860 default_globalize_label (FILE * stream, const char *name)
6862 fputs (GLOBAL_ASM_OP, stream);
6863 assemble_name (stream, name);
6864 putc ('\n', stream);
6866 #endif /* GLOBAL_ASM_OP */
6868 /* Default function to output code that will globalize a declaration. */
6869 void
6870 default_globalize_decl_name (FILE * stream, tree decl)
6872 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
6873 targetm.asm_out.globalize_label (stream, name);
6876 /* Default function to output a label for unwind information. The
6877 default is to do nothing. A target that needs nonlocal labels for
6878 unwind information must provide its own function to do this. */
6879 void
6880 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
6881 tree decl ATTRIBUTE_UNUSED,
6882 int for_eh ATTRIBUTE_UNUSED,
6883 int empty ATTRIBUTE_UNUSED)
6887 /* Default function to output a label to divide up the exception table.
6888 The default is to do nothing. A target that needs/wants to divide
6889 up the table must provide it's own function to do this. */
6890 void
6891 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
6895 /* This is how to output an internal numbered label where PREFIX is
6896 the class of label and LABELNO is the number within the class. */
6898 void
6899 default_generate_internal_label (char *buf, const char *prefix,
6900 unsigned long labelno)
6902 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6905 /* This is how to output an internal numbered label where PREFIX is
6906 the class of label and LABELNO is the number within the class. */
6908 void
6909 default_internal_label (FILE *stream, const char *prefix,
6910 unsigned long labelno)
6912 char *const buf = (char *) alloca (40 + strlen (prefix));
6913 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6914 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
6918 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
6920 void
6921 default_asm_declare_constant_name (FILE *file, const char *name,
6922 const_tree exp ATTRIBUTE_UNUSED,
6923 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
6925 assemble_label (file, name);
6928 /* This is the default behavior at the beginning of a file. It's
6929 controlled by two other target-hook toggles. */
6930 void
6931 default_file_start (void)
6933 if (targetm.asm_file_start_app_off
6934 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
6935 fputs (ASM_APP_OFF, asm_out_file);
6937 if (targetm.asm_file_start_file_directive)
6938 output_file_directive (asm_out_file, main_input_filename);
6941 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
6942 which emits a special section directive used to indicate whether or
6943 not this object file needs an executable stack. This is primarily
6944 a GNU extension to ELF but could be used on other targets. */
6946 int trampolines_created;
6948 void
6949 file_end_indicate_exec_stack (void)
6951 unsigned int flags = SECTION_DEBUG;
6952 if (trampolines_created)
6953 flags |= SECTION_CODE;
6955 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
6958 /* Emit a special section directive to indicate that this object file
6959 was compiled with -fsplit-stack. This is used to let the linker
6960 detect calls between split-stack code and non-split-stack code, so
6961 that it can modify the split-stack code to allocate a sufficiently
6962 large stack. We emit another special section if there are any
6963 functions in this file which have the no_split_stack attribute, to
6964 prevent the linker from warning about being unable to convert the
6965 functions if they call non-split-stack code. */
6967 void
6968 file_end_indicate_split_stack (void)
6970 if (flag_split_stack)
6972 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
6973 NULL));
6974 if (saw_no_split_stack)
6975 switch_to_section (get_section (".note.GNU-no-split-stack",
6976 SECTION_DEBUG, NULL));
6980 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
6981 a get_unnamed_section callback. */
6983 void
6984 output_section_asm_op (const void *directive)
6986 fprintf (asm_out_file, "%s\n", (const char *) directive);
6989 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
6990 the current section is NEW_SECTION. */
6992 void
6993 switch_to_section (section *new_section)
6995 if (in_section == new_section)
6996 return;
6998 if (new_section->common.flags & SECTION_FORGET)
6999 in_section = NULL;
7000 else
7001 in_section = new_section;
7003 switch (SECTION_STYLE (new_section))
7005 case SECTION_NAMED:
7006 targetm.asm_out.named_section (new_section->named.name,
7007 new_section->named.common.flags,
7008 new_section->named.decl);
7009 break;
7011 case SECTION_UNNAMED:
7012 new_section->unnamed.callback (new_section->unnamed.data);
7013 break;
7015 case SECTION_NOSWITCH:
7016 gcc_unreachable ();
7017 break;
7020 new_section->common.flags |= SECTION_DECLARED;
7023 /* If block symbol SYMBOL has not yet been assigned an offset, place
7024 it at the end of its block. */
7026 void
7027 place_block_symbol (rtx symbol)
7029 unsigned HOST_WIDE_INT size, mask, offset;
7030 struct constant_descriptor_rtx *desc;
7031 unsigned int alignment;
7032 struct object_block *block;
7033 tree decl;
7035 gcc_assert (SYMBOL_REF_BLOCK (symbol));
7036 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7037 return;
7039 /* Work out the symbol's size and alignment. */
7040 if (CONSTANT_POOL_ADDRESS_P (symbol))
7042 desc = SYMBOL_REF_CONSTANT (symbol);
7043 alignment = desc->align;
7044 size = GET_MODE_SIZE (desc->mode);
7046 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7048 decl = SYMBOL_REF_DECL (symbol);
7049 alignment = DECL_ALIGN (decl);
7050 size = get_constant_size (DECL_INITIAL (decl));
7051 if ((flag_sanitize & SANITIZE_ADDRESS)
7052 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7053 && asan_protect_global (DECL_INITIAL (decl)))
7054 size += asan_red_zone_size (size);
7056 else
7058 struct symtab_node *snode;
7059 decl = SYMBOL_REF_DECL (symbol);
7061 snode = symtab_node::get (decl);
7062 if (snode->alias)
7064 rtx target = DECL_RTL (snode->ultimate_alias_target ()->decl);
7066 place_block_symbol (target);
7067 SYMBOL_REF_BLOCK_OFFSET (symbol) = SYMBOL_REF_BLOCK_OFFSET (target);
7068 return;
7070 alignment = get_variable_align (decl);
7071 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7072 if ((flag_sanitize & SANITIZE_ADDRESS)
7073 && asan_protect_global (decl))
7075 size += asan_red_zone_size (size);
7076 alignment = MAX (alignment,
7077 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7081 /* Calculate the object's offset from the start of the block. */
7082 block = SYMBOL_REF_BLOCK (symbol);
7083 mask = alignment / BITS_PER_UNIT - 1;
7084 offset = (block->size + mask) & ~mask;
7085 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7087 /* Record the block's new alignment and size. */
7088 block->alignment = MAX (block->alignment, alignment);
7089 block->size = offset + size;
7091 vec_safe_push (block->objects, symbol);
7094 /* Return the anchor that should be used to address byte offset OFFSET
7095 from the first object in BLOCK. MODEL is the TLS model used
7096 to access it. */
7099 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7100 enum tls_model model)
7102 char label[100];
7103 unsigned int begin, middle, end;
7104 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7105 rtx anchor;
7107 /* Work out the anchor's offset. Use an offset of 0 for the first
7108 anchor so that we don't pessimize the case where we take the address
7109 of a variable at the beginning of the block. This is particularly
7110 useful when a block has only one variable assigned to it.
7112 We try to place anchors RANGE bytes apart, so there can then be
7113 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7114 a ptr_mode offset. With some target settings, the lowest such
7115 anchor might be out of range for the lowest ptr_mode offset;
7116 likewise the highest anchor for the highest offset. Use anchors
7117 at the extreme ends of the ptr_mode range in such cases.
7119 All arithmetic uses unsigned integers in order to avoid
7120 signed overflow. */
7121 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7122 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7123 range = max_offset - min_offset + 1;
7124 if (range == 0)
7125 offset = 0;
7126 else
7128 bias = 1 << (GET_MODE_BITSIZE (ptr_mode) - 1);
7129 if (offset < 0)
7131 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7132 delta -= delta % range;
7133 if (delta > bias)
7134 delta = bias;
7135 offset = (HOST_WIDE_INT) (-delta);
7137 else
7139 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7140 delta -= delta % range;
7141 if (delta > bias - 1)
7142 delta = bias - 1;
7143 offset = (HOST_WIDE_INT) delta;
7147 /* Do a binary search to see if there's already an anchor we can use.
7148 Set BEGIN to the new anchor's index if not. */
7149 begin = 0;
7150 end = vec_safe_length (block->anchors);
7151 while (begin != end)
7153 middle = (end + begin) / 2;
7154 anchor = (*block->anchors)[middle];
7155 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7156 end = middle;
7157 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7158 begin = middle + 1;
7159 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7160 end = middle;
7161 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7162 begin = middle + 1;
7163 else
7164 return anchor;
7167 /* Create a new anchor with a unique label. */
7168 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7169 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7170 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7171 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7173 /* Insert it at index BEGIN. */
7174 vec_safe_insert (block->anchors, begin, anchor);
7175 return anchor;
7178 /* Output the objects in BLOCK. */
7180 static void
7181 output_object_block (struct object_block *block)
7183 struct constant_descriptor_rtx *desc;
7184 unsigned int i;
7185 HOST_WIDE_INT offset;
7186 tree decl;
7187 rtx symbol;
7189 if (!block->objects)
7190 return;
7192 /* Switch to the section and make sure that the first byte is
7193 suitably aligned. */
7194 switch_to_section (block->sect);
7195 assemble_align (block->alignment);
7197 /* Define the values of all anchors relative to the current section
7198 position. */
7199 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7200 targetm.asm_out.output_anchor (symbol);
7202 /* Output the objects themselves. */
7203 offset = 0;
7204 FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7206 /* Move to the object's offset, padding with zeros if necessary. */
7207 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7208 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7209 if (CONSTANT_POOL_ADDRESS_P (symbol))
7211 desc = SYMBOL_REF_CONSTANT (symbol);
7212 output_constant_pool_1 (desc, 1);
7213 offset += GET_MODE_SIZE (desc->mode);
7215 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7217 HOST_WIDE_INT size;
7218 decl = SYMBOL_REF_DECL (symbol);
7219 assemble_constant_contents (DECL_INITIAL (decl), XSTR (symbol, 0),
7220 DECL_ALIGN (decl));
7221 size = get_constant_size (DECL_INITIAL (decl));
7222 offset += size;
7223 if ((flag_sanitize & SANITIZE_ADDRESS)
7224 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7225 && asan_protect_global (DECL_INITIAL (decl)))
7227 size = asan_red_zone_size (size);
7228 assemble_zeros (size);
7229 offset += size;
7232 else
7234 HOST_WIDE_INT size;
7235 decl = SYMBOL_REF_DECL (symbol);
7236 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7237 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7238 offset += size;
7239 if ((flag_sanitize & SANITIZE_ADDRESS)
7240 && asan_protect_global (decl))
7242 size = asan_red_zone_size (size);
7243 assemble_zeros (size);
7244 offset += size;
7250 /* A htab_traverse callback used to call output_object_block for
7251 each member of object_block_htab. */
7254 output_object_block_htab (object_block **slot, void *)
7256 output_object_block (*slot);
7257 return 1;
7260 /* Output the definitions of all object_blocks. */
7262 void
7263 output_object_blocks (void)
7265 object_block_htab->traverse<void *, output_object_block_htab> (NULL);
7268 /* This function provides a possible implementation of the
7269 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7270 by -frecord-gcc-switches it creates a new mergeable, string section in the
7271 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7272 contains the switches in ASCII format.
7274 FIXME: This code does not correctly handle double quote characters
7275 that appear inside strings, (it strips them rather than preserving them).
7276 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7277 characters - instead it treats them as sub-string separators. Since
7278 we want to emit NUL strings terminators into the object file we have to use
7279 ASM_OUTPUT_SKIP. */
7282 elf_record_gcc_switches (print_switch_type type, const char * name)
7284 switch (type)
7286 case SWITCH_TYPE_PASSED:
7287 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7288 ASM_OUTPUT_SKIP (asm_out_file, (unsigned HOST_WIDE_INT) 1);
7289 break;
7291 case SWITCH_TYPE_DESCRIPTIVE:
7292 if (name == NULL)
7294 /* Distinguish between invocations where name is NULL. */
7295 static bool started = false;
7297 if (!started)
7299 section * sec;
7301 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7302 SECTION_DEBUG
7303 | SECTION_MERGE
7304 | SECTION_STRINGS
7305 | (SECTION_ENTSIZE & 1),
7306 NULL);
7307 switch_to_section (sec);
7308 started = true;
7312 default:
7313 break;
7316 /* The return value is currently ignored by the caller, but must be 0.
7317 For -fverbose-asm the return value would be the number of characters
7318 emitted into the assembler file. */
7319 return 0;
7322 /* Emit text to declare externally defined symbols. It is needed to
7323 properly support non-default visibility. */
7324 void
7325 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7326 tree decl,
7327 const char *name ATTRIBUTE_UNUSED)
7329 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7330 set in order to avoid putting out names that are never really
7331 used. */
7332 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7333 && targetm.binds_local_p (decl))
7334 maybe_assemble_visibility (decl);
7337 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7339 void
7340 default_asm_output_source_filename (FILE *file, const char *name)
7342 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7343 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7344 #else
7345 fprintf (file, "\t.file\t");
7346 output_quoted_string (file, name);
7347 putc ('\n', file);
7348 #endif
7351 /* Output a file name in the form wanted by System V. */
7353 void
7354 output_file_directive (FILE *asm_file, const char *input_name)
7356 int len;
7357 const char *na;
7359 if (input_name == NULL)
7360 input_name = "<stdin>";
7361 else
7362 input_name = remap_debug_filename (input_name);
7364 len = strlen (input_name);
7365 na = input_name + len;
7367 /* NA gets INPUT_NAME sans directory names. */
7368 while (na > input_name)
7370 if (IS_DIR_SEPARATOR (na[-1]))
7371 break;
7372 na--;
7375 targetm.asm_out.output_source_filename (asm_file, na);
7378 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7379 EXP. */
7381 make_debug_expr_from_rtl (const_rtx exp)
7383 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7384 enum machine_mode mode = GET_MODE (exp);
7385 rtx dval;
7387 DECL_ARTIFICIAL (ddecl) = 1;
7388 if (REG_P (exp) && REG_EXPR (exp))
7389 type = TREE_TYPE (REG_EXPR (exp));
7390 else if (MEM_P (exp) && MEM_EXPR (exp))
7391 type = TREE_TYPE (MEM_EXPR (exp));
7392 else
7393 type = NULL_TREE;
7394 if (type && TYPE_MODE (type) == mode)
7395 TREE_TYPE (ddecl) = type;
7396 else
7397 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7398 DECL_MODE (ddecl) = mode;
7399 dval = gen_rtx_DEBUG_EXPR (mode);
7400 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7401 SET_DECL_RTL (ddecl, dval);
7402 return dval;
7405 #ifdef ELF_ASCII_ESCAPES
7406 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7408 void
7409 default_elf_asm_output_limited_string (FILE *f, const char *s)
7411 int escape;
7412 unsigned char c;
7414 fputs (STRING_ASM_OP, f);
7415 putc ('"', f);
7416 while (*s != '\0')
7418 c = *s;
7419 escape = ELF_ASCII_ESCAPES[c];
7420 switch (escape)
7422 case 0:
7423 putc (c, f);
7424 break;
7425 case 1:
7426 /* TODO: Print in hex with fast function, important for -flto. */
7427 fprintf (f, "\\%03o", c);
7428 break;
7429 default:
7430 putc ('\\', f);
7431 putc (escape, f);
7432 break;
7434 s++;
7436 putc ('\"', f);
7437 putc ('\n', f);
7440 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7442 void
7443 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7445 const char *limit = s + len;
7446 const char *last_null = NULL;
7447 unsigned bytes_in_chunk = 0;
7448 unsigned char c;
7449 int escape;
7451 for (; s < limit; s++)
7453 const char *p;
7455 if (bytes_in_chunk >= 60)
7457 putc ('\"', f);
7458 putc ('\n', f);
7459 bytes_in_chunk = 0;
7462 if (s > last_null)
7464 for (p = s; p < limit && *p != '\0'; p++)
7465 continue;
7466 last_null = p;
7468 else
7469 p = last_null;
7471 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7473 if (bytes_in_chunk > 0)
7475 putc ('\"', f);
7476 putc ('\n', f);
7477 bytes_in_chunk = 0;
7480 default_elf_asm_output_limited_string (f, s);
7481 s = p;
7483 else
7485 if (bytes_in_chunk == 0)
7486 fputs (ASCII_DATA_ASM_OP "\"", f);
7488 c = *s;
7489 escape = ELF_ASCII_ESCAPES[c];
7490 switch (escape)
7492 case 0:
7493 putc (c, f);
7494 bytes_in_chunk++;
7495 break;
7496 case 1:
7497 /* TODO: Print in hex with fast function, important for -flto. */
7498 fprintf (f, "\\%03o", c);
7499 bytes_in_chunk += 4;
7500 break;
7501 default:
7502 putc ('\\', f);
7503 putc (escape, f);
7504 bytes_in_chunk += 2;
7505 break;
7511 if (bytes_in_chunk > 0)
7513 putc ('\"', f);
7514 putc ('\n', f);
7517 #endif
7519 static GTY(()) section *elf_init_array_section;
7520 static GTY(()) section *elf_fini_array_section;
7522 static section *
7523 get_elf_initfini_array_priority_section (int priority,
7524 bool constructor_p)
7526 section *sec;
7527 if (priority != DEFAULT_INIT_PRIORITY)
7529 char buf[18];
7530 sprintf (buf, "%s.%.5u",
7531 constructor_p ? ".init_array" : ".fini_array",
7532 priority);
7533 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7535 else
7537 if (constructor_p)
7539 if (elf_init_array_section == NULL)
7540 elf_init_array_section
7541 = get_section (".init_array",
7542 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7543 sec = elf_init_array_section;
7545 else
7547 if (elf_fini_array_section == NULL)
7548 elf_fini_array_section
7549 = get_section (".fini_array",
7550 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7551 sec = elf_fini_array_section;
7554 return sec;
7557 /* Use .init_array section for constructors. */
7559 void
7560 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7562 section *sec = get_elf_initfini_array_priority_section (priority,
7563 true);
7564 assemble_addr_to_section (symbol, sec);
7567 /* Use .fini_array section for destructors. */
7569 void
7570 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7572 section *sec = get_elf_initfini_array_priority_section (priority,
7573 false);
7574 assemble_addr_to_section (symbol, sec);
7577 /* Default TARGET_ASM_OUTPUT_IDENT hook.
7579 This is a bit of a cheat. The real default is a no-op, but this
7580 hook is the default for all targets with a .ident directive. */
7582 void
7583 default_asm_output_ident_directive (const char *ident_str)
7585 const char *ident_asm_op = "\t.ident\t";
7587 /* If we are still in the front end, do not write out the string
7588 to asm_out_file. Instead, add a fake top-level asm statement.
7589 This allows the front ends to use this hook without actually
7590 writing to asm_out_file, to handle #ident or Pragma Ident. */
7591 if (symtab->state == PARSING)
7593 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
7594 symtab->finalize_toplevel_asm (build_string (strlen (buf), buf));
7596 else
7597 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
7600 #include "gt-varasm.h"