* gcc.dg/guality/guality.exp: Skip on AIX.
[official-gcc.git] / gcc / varasm.c
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1 /* Output variables, constants and external declarations, for GNU compiler.
2 Copyright (C) 1987-2013 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 "flags.h"
35 #include "function.h"
36 #include "expr.h"
37 #include "hard-reg-set.h"
38 #include "regs.h"
39 #include "output.h"
40 #include "diagnostic-core.h"
41 #include "hashtab.h"
42 #include "ggc.h"
43 #include "langhooks.h"
44 #include "tm_p.h"
45 #include "debug.h"
46 #include "target.h"
47 #include "common/common-target.h"
48 #include "targhooks.h"
49 #include "tree-mudflap.h"
50 #include "cgraph.h"
51 #include "pointer-set.h"
52 #include "asan.h"
54 #ifdef XCOFF_DEBUGGING_INFO
55 #include "xcoffout.h" /* Needed for external data
56 declarations for e.g. AIX 4.x. */
57 #endif
59 /* The (assembler) name of the first globally-visible object output. */
60 extern GTY(()) const char *first_global_object_name;
61 extern GTY(()) const char *weak_global_object_name;
63 const char *first_global_object_name;
64 const char *weak_global_object_name;
66 struct addr_const;
67 struct constant_descriptor_rtx;
68 struct rtx_constant_pool;
70 #define n_deferred_constants (crtl->varasm.deferred_constants)
72 /* Number for making the label on the next
73 constant that is stored in memory. */
75 static GTY(()) int const_labelno;
77 /* Carry information from ASM_DECLARE_OBJECT_NAME
78 to ASM_FINISH_DECLARE_OBJECT. */
80 int size_directive_output;
82 /* The last decl for which assemble_variable was called,
83 if it did ASM_DECLARE_OBJECT_NAME.
84 If the last call to assemble_variable didn't do that,
85 this holds 0. */
87 tree last_assemble_variable_decl;
89 /* The following global variable indicates if the first basic block
90 in a function belongs to the cold partition or not. */
92 bool first_function_block_is_cold;
94 /* We give all constants their own alias set. Perhaps redundant with
95 MEM_READONLY_P, but pre-dates it. */
97 static alias_set_type const_alias_set;
99 /* Whether we saw any functions with no_split_stack. */
101 static bool saw_no_split_stack;
103 static const char *strip_reg_name (const char *);
104 static int contains_pointers_p (tree);
105 #ifdef ASM_OUTPUT_EXTERNAL
106 static bool incorporeal_function_p (tree);
107 #endif
108 static void decode_addr_const (tree, struct addr_const *);
109 static hashval_t const_desc_hash (const void *);
110 static int const_desc_eq (const void *, const void *);
111 static hashval_t const_hash_1 (const tree);
112 static int compare_constant (const tree, const tree);
113 static tree copy_constant (tree);
114 static void output_constant_def_contents (rtx);
115 static void output_addressed_constants (tree);
116 static unsigned HOST_WIDE_INT array_size_for_constructor (tree);
117 static unsigned min_align (unsigned, unsigned);
118 static void globalize_decl (tree);
119 static bool decl_readonly_section_1 (enum section_category);
120 #ifdef BSS_SECTION_ASM_OP
121 #ifdef ASM_OUTPUT_ALIGNED_BSS
122 static void asm_output_aligned_bss (FILE *, tree, const char *,
123 unsigned HOST_WIDE_INT, int)
124 ATTRIBUTE_UNUSED;
125 #endif
126 #endif /* BSS_SECTION_ASM_OP */
127 static void mark_weak (tree);
128 static void output_constant_pool (const char *, tree);
130 /* Well-known sections, each one associated with some sort of *_ASM_OP. */
131 section *text_section;
132 section *data_section;
133 section *readonly_data_section;
134 section *sdata_section;
135 section *ctors_section;
136 section *dtors_section;
137 section *bss_section;
138 section *sbss_section;
140 /* Various forms of common section. All are guaranteed to be nonnull. */
141 section *tls_comm_section;
142 section *comm_section;
143 section *lcomm_section;
145 /* A SECTION_NOSWITCH section used for declaring global BSS variables.
146 May be null. */
147 section *bss_noswitch_section;
149 /* The section that holds the main exception table, when known. The section
150 is set either by the target's init_sections hook or by the first call to
151 switch_to_exception_section. */
152 section *exception_section;
154 /* The section that holds the DWARF2 frame unwind information, when known.
155 The section is set either by the target's init_sections hook or by the
156 first call to switch_to_eh_frame_section. */
157 section *eh_frame_section;
159 /* asm_out_file's current section. This is NULL if no section has yet
160 been selected or if we lose track of what the current section is. */
161 section *in_section;
163 /* True if code for the current function is currently being directed
164 at the cold section. */
165 bool in_cold_section_p;
167 /* A linked list of all the unnamed sections. */
168 static GTY(()) section *unnamed_sections;
170 /* Return a nonzero value if DECL has a section attribute. */
171 #define IN_NAMED_SECTION(DECL) \
172 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \
173 && DECL_SECTION_NAME (DECL) != NULL_TREE)
175 /* Hash table of named sections. */
176 static GTY((param_is (section))) htab_t section_htab;
178 /* A table of object_blocks, indexed by section. */
179 static GTY((param_is (struct object_block))) htab_t object_block_htab;
181 /* The next number to use for internal anchor labels. */
182 static GTY(()) int anchor_labelno;
184 /* A pool of constants that can be shared between functions. */
185 static GTY(()) struct rtx_constant_pool *shared_constant_pool;
187 /* Helper routines for maintaining section_htab. */
189 static int
190 section_entry_eq (const void *p1, const void *p2)
192 const section *old = (const section *) p1;
193 const char *new_name = (const char *) p2;
195 return strcmp (old->named.name, new_name) == 0;
198 static hashval_t
199 section_entry_hash (const void *p)
201 const section *old = (const section *) p;
202 return htab_hash_string (old->named.name);
205 /* Return a hash value for section SECT. */
207 static hashval_t
208 hash_section (section *sect)
210 if (sect->common.flags & SECTION_NAMED)
211 return htab_hash_string (sect->named.name);
212 return sect->common.flags;
215 /* Helper routines for maintaining object_block_htab. */
217 static int
218 object_block_entry_eq (const void *p1, const void *p2)
220 const struct object_block *old = (const struct object_block *) p1;
221 const section *new_section = (const section *) p2;
223 return old->sect == new_section;
226 static hashval_t
227 object_block_entry_hash (const void *p)
229 const struct object_block *old = (const struct object_block *) p;
230 return hash_section (old->sect);
233 /* Return a new unnamed section with the given fields. */
235 section *
236 get_unnamed_section (unsigned int flags, void (*callback) (const void *),
237 const void *data)
239 section *sect;
241 sect = ggc_alloc_section ();
242 sect->unnamed.common.flags = flags | SECTION_UNNAMED;
243 sect->unnamed.callback = callback;
244 sect->unnamed.data = data;
245 sect->unnamed.next = unnamed_sections;
247 unnamed_sections = sect;
248 return sect;
251 /* Return a SECTION_NOSWITCH section with the given fields. */
253 static section *
254 get_noswitch_section (unsigned int flags, noswitch_section_callback callback)
256 section *sect;
258 sect = ggc_alloc_section ();
259 sect->noswitch.common.flags = flags | SECTION_NOSWITCH;
260 sect->noswitch.callback = callback;
262 return sect;
265 /* Return the named section structure associated with NAME. Create
266 a new section with the given fields if no such structure exists. */
268 section *
269 get_section (const char *name, unsigned int flags, tree decl)
271 section *sect, **slot;
273 slot = (section **)
274 htab_find_slot_with_hash (section_htab, name,
275 htab_hash_string (name), INSERT);
276 flags |= SECTION_NAMED;
277 if (*slot == NULL)
279 sect = ggc_alloc_section ();
280 sect->named.common.flags = flags;
281 sect->named.name = ggc_strdup (name);
282 sect->named.decl = decl;
283 *slot = sect;
285 else
287 sect = *slot;
288 if ((sect->common.flags & ~SECTION_DECLARED) != flags
289 && ((sect->common.flags | flags) & SECTION_OVERRIDE) == 0)
291 /* It is fine if one of the section flags is
292 SECTION_WRITE | SECTION_RELRO and the other has none of these
293 flags (i.e. read-only) in named sections and either the
294 section hasn't been declared yet or has been declared as writable.
295 In that case just make sure the resulting flags are
296 SECTION_WRITE | SECTION_RELRO, ie. writable only because of
297 relocations. */
298 if (((sect->common.flags ^ flags) & (SECTION_WRITE | SECTION_RELRO))
299 == (SECTION_WRITE | SECTION_RELRO)
300 && (sect->common.flags
301 & ~(SECTION_DECLARED | SECTION_WRITE | SECTION_RELRO))
302 == (flags & ~(SECTION_WRITE | SECTION_RELRO))
303 && ((sect->common.flags & SECTION_DECLARED) == 0
304 || (sect->common.flags & SECTION_WRITE)))
306 sect->common.flags |= (SECTION_WRITE | SECTION_RELRO);
307 return sect;
309 /* Sanity check user variables for flag changes. */
310 if (sect->named.decl != NULL
311 && DECL_P (sect->named.decl)
312 && decl != sect->named.decl)
314 if (decl != NULL && DECL_P (decl))
315 error ("%+D causes a section type conflict with %D",
316 decl, sect->named.decl);
317 else
318 error ("section type conflict with %D", sect->named.decl);
319 inform (DECL_SOURCE_LOCATION (sect->named.decl),
320 "%qD was declared here", sect->named.decl);
322 else if (decl != NULL && DECL_P (decl))
323 error ("%+D causes a section type conflict", decl);
324 else
325 error ("section type conflict");
326 /* Make sure we don't error about one section multiple times. */
327 sect->common.flags |= SECTION_OVERRIDE;
330 return sect;
333 /* Return true if the current compilation mode benefits from having
334 objects grouped into blocks. */
336 static bool
337 use_object_blocks_p (void)
339 return flag_section_anchors;
342 /* Return the object_block structure for section SECT. Create a new
343 structure if we haven't created one already. Return null if SECT
344 itself is null. */
346 static struct object_block *
347 get_block_for_section (section *sect)
349 struct object_block *block;
350 void **slot;
352 if (sect == NULL)
353 return NULL;
355 slot = htab_find_slot_with_hash (object_block_htab, sect,
356 hash_section (sect), INSERT);
357 block = (struct object_block *) *slot;
358 if (block == NULL)
360 block = ggc_alloc_cleared_object_block ();
361 block->sect = sect;
362 *slot = block;
364 return block;
367 /* Create a symbol with label LABEL and place it at byte offset
368 OFFSET in BLOCK. OFFSET can be negative if the symbol's offset
369 is not yet known. LABEL must be a garbage-collected string. */
371 static rtx
372 create_block_symbol (const char *label, struct object_block *block,
373 HOST_WIDE_INT offset)
375 rtx symbol;
376 unsigned int size;
378 /* Create the extended SYMBOL_REF. */
379 size = RTX_HDR_SIZE + sizeof (struct block_symbol);
380 symbol = ggc_alloc_rtx_def (size);
382 /* Initialize the normal SYMBOL_REF fields. */
383 memset (symbol, 0, size);
384 PUT_CODE (symbol, SYMBOL_REF);
385 PUT_MODE (symbol, Pmode);
386 XSTR (symbol, 0) = label;
387 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_HAS_BLOCK_INFO;
389 /* Initialize the block_symbol stuff. */
390 SYMBOL_REF_BLOCK (symbol) = block;
391 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
393 return symbol;
396 /* Return a section with a particular name and with whatever SECTION_*
397 flags section_type_flags deems appropriate. The name of the section
398 is taken from NAME if nonnull, otherwise it is taken from DECL's
399 DECL_SECTION_NAME. DECL is the decl associated with the section
400 (see the section comment for details) and RELOC is as for
401 section_type_flags. */
403 section *
404 get_named_section (tree decl, const char *name, int reloc)
406 unsigned int flags;
408 if (name == NULL)
410 gcc_assert (decl && DECL_P (decl) && DECL_SECTION_NAME (decl));
411 name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
414 flags = targetm.section_type_flags (decl, name, reloc);
415 return get_section (name, flags, decl);
418 /* If required, set DECL_SECTION_NAME to a unique name. */
420 void
421 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
422 int flag_function_or_data_sections)
424 if (DECL_SECTION_NAME (decl) == NULL_TREE
425 && targetm_common.have_named_sections
426 && (flag_function_or_data_sections
427 || DECL_ONE_ONLY (decl)))
429 targetm.asm_out.unique_section (decl, reloc);
430 DECL_HAS_IMPLICIT_SECTION_NAME_P (decl) = true;
434 #ifdef BSS_SECTION_ASM_OP
436 #ifdef ASM_OUTPUT_ALIGNED_BSS
438 /* Utility function for targets to use in implementing
439 ASM_OUTPUT_ALIGNED_BSS.
440 ??? It is believed that this function will work in most cases so such
441 support is localized here. */
443 static void
444 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
445 const char *name, unsigned HOST_WIDE_INT size,
446 int align)
448 switch_to_section (bss_section);
449 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
450 #ifdef ASM_DECLARE_OBJECT_NAME
451 last_assemble_variable_decl = decl;
452 ASM_DECLARE_OBJECT_NAME (file, name, decl);
453 #else
454 /* Standard thing is just output label for the object. */
455 ASM_OUTPUT_LABEL (file, name);
456 #endif /* ASM_DECLARE_OBJECT_NAME */
457 ASM_OUTPUT_SKIP (file, size ? size : 1);
460 #endif
462 #endif /* BSS_SECTION_ASM_OP */
464 #ifndef USE_SELECT_SECTION_FOR_FUNCTIONS
465 /* Return the hot section for function DECL. Return text_section for
466 null DECLs. */
468 static section *
469 hot_function_section (tree decl)
471 if (decl != NULL_TREE
472 && DECL_SECTION_NAME (decl) != NULL_TREE
473 && targetm_common.have_named_sections)
474 return get_named_section (decl, NULL, 0);
475 else
476 return text_section;
478 #endif
480 /* Return section for TEXT_SECTION_NAME if DECL or DECL_SECTION_NAME (DECL)
481 is NULL.
483 When DECL_SECTION_NAME is non-NULL and it is implicit section and
484 NAMED_SECTION_SUFFIX is non-NULL, then produce section called
485 concatenate the name with NAMED_SECTION_SUFFIX.
486 Otherwise produce "TEXT_SECTION_NAME.IMPLICIT_NAME". */
488 section *
489 get_named_text_section (tree decl,
490 const char *text_section_name,
491 const char *named_section_suffix)
493 if (decl && DECL_SECTION_NAME (decl))
495 if (named_section_suffix)
497 tree dsn = DECL_SECTION_NAME (decl);
498 const char *stripped_name;
499 char *name, *buffer;
501 name = (char *) alloca (TREE_STRING_LENGTH (dsn) + 1);
502 memcpy (name, TREE_STRING_POINTER (dsn),
503 TREE_STRING_LENGTH (dsn) + 1);
505 stripped_name = targetm.strip_name_encoding (name);
507 buffer = ACONCAT ((stripped_name, named_section_suffix, NULL));
508 return get_named_section (decl, buffer, 0);
510 else if (DECL_HAS_IMPLICIT_SECTION_NAME_P (decl))
512 const char *name;
514 /* Do not try to split gnu_linkonce functions. This gets somewhat
515 slipperly. */
516 if (DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP)
517 return NULL;
518 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
519 name = targetm.strip_name_encoding (name);
520 return get_named_section (decl, ACONCAT ((text_section_name, ".",
521 name, NULL)), 0);
523 else
524 return NULL;
526 return get_named_section (decl, text_section_name, 0);
529 /* Choose named function section based on its frequency. */
531 section *
532 default_function_section (tree decl, enum node_frequency freq,
533 bool startup, bool exit)
535 #if defined HAVE_LD_EH_GC_SECTIONS && defined HAVE_LD_EH_GC_SECTIONS_BUG
536 /* Old GNU linkers have buggy --gc-section support, which sometimes
537 results in .gcc_except_table* sections being garbage collected. */
538 if (decl
539 && DECL_SECTION_NAME (decl)
540 && DECL_HAS_IMPLICIT_SECTION_NAME_P (decl))
541 return NULL;
542 #endif
544 if (!flag_reorder_functions
545 || !targetm_common.have_named_sections)
546 return NULL;
547 /* Startup code should go to startup subsection unless it is
548 unlikely executed (this happens especially with function splitting
549 where we can split away unnecessary parts of static constructors. */
550 if (startup && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
551 return get_named_text_section (decl, ".text.startup", NULL);
553 /* Similarly for exit. */
554 if (exit && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
555 return get_named_text_section (decl, ".text.exit", NULL);
557 /* Group cold functions together, similarly for hot code. */
558 switch (freq)
560 case NODE_FREQUENCY_UNLIKELY_EXECUTED:
561 return get_named_text_section (decl, ".text.unlikely", NULL);
562 case NODE_FREQUENCY_HOT:
563 return get_named_text_section (decl, ".text.hot", NULL);
564 default:
565 return NULL;
569 /* Return the section for function DECL.
571 If DECL is NULL_TREE, return the text section. We can be passed
572 NULL_TREE under some circumstances by dbxout.c at least.
574 If FORCE_COLD is true, return cold function section ignoring
575 the frequency info of cgraph_node. */
577 static section *
578 function_section_1 (tree decl, bool force_cold)
580 section *section = NULL;
581 enum node_frequency freq = NODE_FREQUENCY_NORMAL;
582 bool startup = false, exit = false;
584 if (decl)
586 struct cgraph_node *node = cgraph_get_node (decl);
588 if (node)
590 freq = node->frequency;
591 startup = node->only_called_at_startup;
592 exit = node->only_called_at_exit;
595 if (force_cold)
596 freq = NODE_FREQUENCY_UNLIKELY_EXECUTED;
598 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
599 if (decl != NULL_TREE
600 && DECL_SECTION_NAME (decl) != NULL_TREE)
602 if (targetm.asm_out.function_section)
603 section = targetm.asm_out.function_section (decl, freq,
604 startup, exit);
605 if (section)
606 return section;
607 return get_named_section (decl, NULL, 0);
609 else
610 return targetm.asm_out.select_section
611 (decl, freq == NODE_FREQUENCY_UNLIKELY_EXECUTED,
612 DECL_ALIGN (decl));
613 #else
614 if (targetm.asm_out.function_section)
615 section = targetm.asm_out.function_section (decl, freq, startup, exit);
616 if (section)
617 return section;
618 return hot_function_section (decl);
619 #endif
622 /* Return the section for function DECL.
624 If DECL is NULL_TREE, return the text section. We can be passed
625 NULL_TREE under some circumstances by dbxout.c at least. */
627 section *
628 function_section (tree decl)
630 /* Handle cases where function splitting code decides
631 to put function entry point into unlikely executed section
632 despite the fact that the function itself is not cold
633 (i.e. it is called rarely but contains a hot loop that is
634 better to live in hot subsection for the code locality). */
635 return function_section_1 (decl,
636 first_function_block_is_cold);
639 /* Return the section for the current function, take IN_COLD_SECTION_P
640 into account. */
642 section *
643 current_function_section (void)
645 return function_section_1 (current_function_decl, in_cold_section_p);
648 /* Tell assembler to switch to unlikely-to-be-executed text section. */
650 section *
651 unlikely_text_section (void)
653 return function_section_1 (current_function_decl, true);
656 /* When called within a function context, return true if the function
657 has been assigned a cold text section and if SECT is that section.
658 When called outside a function context, return true if SECT is the
659 default cold section. */
661 bool
662 unlikely_text_section_p (section *sect)
664 return sect == function_section_1 (current_function_decl, true);
667 /* Return the read-only data section associated with function DECL. */
669 section *
670 default_function_rodata_section (tree decl)
672 if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
674 const char *name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
676 if (DECL_ONE_ONLY (decl) && HAVE_COMDAT_GROUP)
678 const char *dot;
679 size_t len;
680 char* rname;
682 dot = strchr (name + 1, '.');
683 if (!dot)
684 dot = name;
685 len = strlen (dot) + 8;
686 rname = (char *) alloca (len);
688 strcpy (rname, ".rodata");
689 strcat (rname, dot);
690 return get_section (rname, SECTION_LINKONCE, decl);
692 /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo. */
693 else if (DECL_ONE_ONLY (decl)
694 && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
696 size_t len = strlen (name) + 1;
697 char *rname = (char *) alloca (len);
699 memcpy (rname, name, len);
700 rname[14] = 'r';
701 return get_section (rname, SECTION_LINKONCE, decl);
703 /* For .text.foo we want to use .rodata.foo. */
704 else if (flag_function_sections && flag_data_sections
705 && strncmp (name, ".text.", 6) == 0)
707 size_t len = strlen (name) + 1;
708 char *rname = (char *) alloca (len + 2);
710 memcpy (rname, ".rodata", 7);
711 memcpy (rname + 7, name + 5, len - 5);
712 return get_section (rname, 0, decl);
716 return readonly_data_section;
719 /* Return the read-only data section associated with function DECL
720 for targets where that section should be always the single
721 readonly data section. */
723 section *
724 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
726 return readonly_data_section;
729 /* Return the section to use for string merging. */
731 static section *
732 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
733 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
734 unsigned int flags ATTRIBUTE_UNUSED)
736 HOST_WIDE_INT len;
738 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
739 && TREE_CODE (decl) == STRING_CST
740 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
741 && align <= 256
742 && (len = int_size_in_bytes (TREE_TYPE (decl))) > 0
743 && TREE_STRING_LENGTH (decl) >= len)
745 enum machine_mode mode;
746 unsigned int modesize;
747 const char *str;
748 HOST_WIDE_INT i;
749 int j, unit;
750 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
751 char *name = (char *) alloca (strlen (prefix) + 30);
753 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
754 modesize = GET_MODE_BITSIZE (mode);
755 if (modesize >= 8 && modesize <= 256
756 && (modesize & (modesize - 1)) == 0)
758 if (align < modesize)
759 align = modesize;
761 str = TREE_STRING_POINTER (decl);
762 unit = GET_MODE_SIZE (mode);
764 /* Check for embedded NUL characters. */
765 for (i = 0; i < len; i += unit)
767 for (j = 0; j < unit; j++)
768 if (str[i + j] != '\0')
769 break;
770 if (j == unit)
771 break;
773 if (i == len - unit)
775 sprintf (name, "%s.str%d.%d", prefix,
776 modesize / 8, (int) (align / 8));
777 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
778 return get_section (name, flags, NULL);
783 return readonly_data_section;
786 /* Return the section to use for constant merging. */
788 section *
789 mergeable_constant_section (enum machine_mode mode ATTRIBUTE_UNUSED,
790 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
791 unsigned int flags ATTRIBUTE_UNUSED)
793 unsigned int modesize = GET_MODE_BITSIZE (mode);
795 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
796 && mode != VOIDmode
797 && mode != BLKmode
798 && modesize <= align
799 && align >= 8
800 && align <= 256
801 && (align & (align - 1)) == 0)
803 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
804 char *name = (char *) alloca (strlen (prefix) + 30);
806 sprintf (name, "%s.cst%d", prefix, (int) (align / 8));
807 flags |= (align / 8) | SECTION_MERGE;
808 return get_section (name, flags, NULL);
810 return readonly_data_section;
813 /* Given NAME, a putative register name, discard any customary prefixes. */
815 static const char *
816 strip_reg_name (const char *name)
818 #ifdef REGISTER_PREFIX
819 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
820 name += strlen (REGISTER_PREFIX);
821 #endif
822 if (name[0] == '%' || name[0] == '#')
823 name++;
824 return name;
827 /* The user has asked for a DECL to have a particular name. Set (or
828 change) it in such a way that we don't prefix an underscore to
829 it. */
830 void
831 set_user_assembler_name (tree decl, const char *name)
833 char *starred = (char *) alloca (strlen (name) + 2);
834 starred[0] = '*';
835 strcpy (starred + 1, name);
836 change_decl_assembler_name (decl, get_identifier (starred));
837 SET_DECL_RTL (decl, NULL_RTX);
840 /* Decode an `asm' spec for a declaration as a register name.
841 Return the register number, or -1 if nothing specified,
842 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
843 or -3 if ASMSPEC is `cc' and is not recognized,
844 or -4 if ASMSPEC is `memory' and is not recognized.
845 Accept an exact spelling or a decimal number.
846 Prefixes such as % are optional. */
849 decode_reg_name_and_count (const char *asmspec, int *pnregs)
851 /* Presume just one register is clobbered. */
852 *pnregs = 1;
854 if (asmspec != 0)
856 int i;
858 /* Get rid of confusing prefixes. */
859 asmspec = strip_reg_name (asmspec);
861 /* Allow a decimal number as a "register name". */
862 for (i = strlen (asmspec) - 1; i >= 0; i--)
863 if (! ISDIGIT (asmspec[i]))
864 break;
865 if (asmspec[0] != 0 && i < 0)
867 i = atoi (asmspec);
868 if (i < FIRST_PSEUDO_REGISTER && i >= 0)
869 return i;
870 else
871 return -2;
874 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
875 if (reg_names[i][0]
876 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
877 return i;
879 #ifdef OVERLAPPING_REGISTER_NAMES
881 static const struct
883 const char *const name;
884 const int number;
885 const int nregs;
886 } table[] = OVERLAPPING_REGISTER_NAMES;
888 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
889 if (table[i].name[0]
890 && ! strcmp (asmspec, table[i].name))
892 *pnregs = table[i].nregs;
893 return table[i].number;
896 #endif /* OVERLAPPING_REGISTER_NAMES */
898 #ifdef ADDITIONAL_REGISTER_NAMES
900 static const struct { const char *const name; const int number; } table[]
901 = ADDITIONAL_REGISTER_NAMES;
903 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
904 if (table[i].name[0]
905 && ! strcmp (asmspec, table[i].name))
906 return table[i].number;
908 #endif /* ADDITIONAL_REGISTER_NAMES */
910 if (!strcmp (asmspec, "memory"))
911 return -4;
913 if (!strcmp (asmspec, "cc"))
914 return -3;
916 return -2;
919 return -1;
923 decode_reg_name (const char *name)
925 int count;
926 return decode_reg_name_and_count (name, &count);
930 /* Return true if DECL's initializer is suitable for a BSS section. */
932 bool
933 bss_initializer_p (const_tree decl)
935 return (DECL_INITIAL (decl) == NULL
936 || DECL_INITIAL (decl) == error_mark_node
937 || (flag_zero_initialized_in_bss
938 /* Leave constant zeroes in .rodata so they
939 can be shared. */
940 && !TREE_READONLY (decl)
941 && initializer_zerop (DECL_INITIAL (decl))));
944 /* Compute the alignment of variable specified by DECL.
945 DONT_OUTPUT_DATA is from assemble_variable. */
947 void
948 align_variable (tree decl, bool dont_output_data)
950 unsigned int align = DECL_ALIGN (decl);
952 /* In the case for initialing an array whose length isn't specified,
953 where we have not yet been able to do the layout,
954 figure out the proper alignment now. */
955 if (dont_output_data && DECL_SIZE (decl) == 0
956 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
957 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
959 /* Some object file formats have a maximum alignment which they support.
960 In particular, a.out format supports a maximum alignment of 4. */
961 if (align > MAX_OFILE_ALIGNMENT)
963 warning (0, "alignment of %q+D is greater than maximum object "
964 "file alignment. Using %d", decl,
965 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
966 align = MAX_OFILE_ALIGNMENT;
969 if (! DECL_USER_ALIGN (decl))
971 #ifdef DATA_ABI_ALIGNMENT
972 unsigned int data_abi_align
973 = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
974 /* For backwards compatibility, don't assume the ABI alignment for
975 TLS variables. */
976 if (! DECL_THREAD_LOCAL_P (decl) || data_abi_align <= BITS_PER_WORD)
977 align = data_abi_align;
978 #endif
980 /* On some machines, it is good to increase alignment sometimes.
981 But as DECL_ALIGN is used both for actually emitting the variable
982 and for code accessing the variable as guaranteed alignment, we
983 can only increase the alignment if it is a performance optimization
984 if the references to it must bind to the current definition. */
985 if (decl_binds_to_current_def_p (decl))
987 #ifdef DATA_ALIGNMENT
988 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
989 /* Don't increase alignment too much for TLS variables - TLS space
990 is too precious. */
991 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
992 align = data_align;
993 #endif
994 #ifdef CONSTANT_ALIGNMENT
995 if (DECL_INITIAL (decl) != 0
996 && DECL_INITIAL (decl) != error_mark_node)
998 unsigned int const_align
999 = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
1000 /* Don't increase alignment too much for TLS variables - TLS
1001 space is too precious. */
1002 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1003 align = const_align;
1005 #endif
1009 /* Reset the alignment in case we have made it tighter, so we can benefit
1010 from it in get_pointer_alignment. */
1011 DECL_ALIGN (decl) = align;
1014 /* Return DECL_ALIGN (decl), possibly increased for optimization purposes
1015 beyond what align_variable returned. */
1017 static unsigned int
1018 get_variable_align (tree decl)
1020 unsigned int align = DECL_ALIGN (decl);
1022 /* For user aligned vars or static vars align_variable already did
1023 everything. */
1024 if (DECL_USER_ALIGN (decl) || !TREE_PUBLIC (decl))
1025 return align;
1027 #ifdef DATA_ABI_ALIGNMENT
1028 if (DECL_THREAD_LOCAL_P (decl))
1029 align = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1030 #endif
1032 /* For decls that bind to the current definition, align_variable
1033 did also everything, except for not assuming ABI required alignment
1034 of TLS variables. For other vars, increase the alignment here
1035 as an optimization. */
1036 if (!decl_binds_to_current_def_p (decl))
1038 /* On some machines, it is good to increase alignment sometimes. */
1039 #ifdef DATA_ALIGNMENT
1040 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1041 /* Don't increase alignment too much for TLS variables - TLS space
1042 is too precious. */
1043 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1044 align = data_align;
1045 #endif
1046 #ifdef CONSTANT_ALIGNMENT
1047 if (DECL_INITIAL (decl) != 0 && DECL_INITIAL (decl) != error_mark_node)
1049 unsigned int const_align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl),
1050 align);
1051 /* Don't increase alignment too much for TLS variables - TLS space
1052 is too precious. */
1053 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1054 align = const_align;
1056 #endif
1059 return align;
1062 /* Return the section into which the given VAR_DECL or CONST_DECL
1063 should be placed. PREFER_NOSWITCH_P is true if a noswitch
1064 section should be used wherever possible. */
1066 section *
1067 get_variable_section (tree decl, bool prefer_noswitch_p)
1069 addr_space_t as = ADDR_SPACE_GENERIC;
1070 int reloc;
1072 if (TREE_TYPE (decl) != error_mark_node)
1073 as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1075 if (DECL_COMMON (decl))
1077 /* If the decl has been given an explicit section name, or it resides
1078 in a non-generic address space, then it isn't common, and shouldn't
1079 be handled as such. */
1080 gcc_assert (DECL_SECTION_NAME (decl) == NULL
1081 && ADDR_SPACE_GENERIC_P (as));
1082 if (DECL_THREAD_LOCAL_P (decl))
1083 return tls_comm_section;
1084 else if (TREE_PUBLIC (decl) && bss_initializer_p (decl))
1085 return comm_section;
1088 if (DECL_INITIAL (decl) == error_mark_node)
1089 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1090 else if (DECL_INITIAL (decl))
1091 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1092 else
1093 reloc = 0;
1095 resolve_unique_section (decl, reloc, flag_data_sections);
1096 if (IN_NAMED_SECTION (decl))
1097 return get_named_section (decl, NULL, reloc);
1099 if (ADDR_SPACE_GENERIC_P (as)
1100 && !DECL_THREAD_LOCAL_P (decl)
1101 && !(prefer_noswitch_p && targetm.have_switchable_bss_sections)
1102 && bss_initializer_p (decl))
1104 if (!TREE_PUBLIC (decl)
1105 && !(flag_asan && asan_protect_global (decl)))
1106 return lcomm_section;
1107 if (bss_noswitch_section)
1108 return bss_noswitch_section;
1111 return targetm.asm_out.select_section (decl, reloc,
1112 get_variable_align (decl));
1115 /* Return the block into which object_block DECL should be placed. */
1117 static struct object_block *
1118 get_block_for_decl (tree decl)
1120 section *sect;
1122 if (TREE_CODE (decl) == VAR_DECL)
1124 /* The object must be defined in this translation unit. */
1125 if (DECL_EXTERNAL (decl))
1126 return NULL;
1128 /* There's no point using object blocks for something that is
1129 isolated by definition. */
1130 if (DECL_ONE_ONLY (decl))
1131 return NULL;
1134 /* We can only calculate block offsets if the decl has a known
1135 constant size. */
1136 if (DECL_SIZE_UNIT (decl) == NULL)
1137 return NULL;
1138 if (!host_integerp (DECL_SIZE_UNIT (decl), 1))
1139 return NULL;
1141 /* Find out which section should contain DECL. We cannot put it into
1142 an object block if it requires a standalone definition. */
1143 if (TREE_CODE (decl) == VAR_DECL)
1144 align_variable (decl, 0);
1145 sect = get_variable_section (decl, true);
1146 if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
1147 return NULL;
1149 return get_block_for_section (sect);
1152 /* Make sure block symbol SYMBOL is in block BLOCK. */
1154 static void
1155 change_symbol_block (rtx symbol, struct object_block *block)
1157 if (block != SYMBOL_REF_BLOCK (symbol))
1159 gcc_assert (SYMBOL_REF_BLOCK_OFFSET (symbol) < 0);
1160 SYMBOL_REF_BLOCK (symbol) = block;
1164 /* Return true if it is possible to put DECL in an object_block. */
1166 static bool
1167 use_blocks_for_decl_p (tree decl)
1169 /* Only data DECLs can be placed into object blocks. */
1170 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != CONST_DECL)
1171 return false;
1173 /* Detect decls created by dw2_force_const_mem. Such decls are
1174 special because DECL_INITIAL doesn't specify the decl's true value.
1175 dw2_output_indirect_constants will instead call assemble_variable
1176 with dont_output_data set to 1 and then print the contents itself. */
1177 if (DECL_INITIAL (decl) == decl)
1178 return false;
1180 /* If this decl is an alias, then we don't want to emit a
1181 definition. */
1182 if (lookup_attribute ("alias", DECL_ATTRIBUTES (decl)))
1183 return false;
1185 return targetm.use_blocks_for_decl_p (decl);
1188 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
1189 have static storage duration. In other words, it should not be an
1190 automatic variable, including PARM_DECLs.
1192 There is, however, one exception: this function handles variables
1193 explicitly placed in a particular register by the user.
1195 This is never called for PARM_DECL nodes. */
1197 void
1198 make_decl_rtl (tree decl)
1200 const char *name = 0;
1201 int reg_number;
1202 rtx x;
1204 /* Check that we are not being given an automatic variable. */
1205 gcc_assert (TREE_CODE (decl) != PARM_DECL
1206 && TREE_CODE (decl) != RESULT_DECL);
1208 /* A weak alias has TREE_PUBLIC set but not the other bits. */
1209 gcc_assert (TREE_CODE (decl) != VAR_DECL
1210 || TREE_STATIC (decl)
1211 || TREE_PUBLIC (decl)
1212 || DECL_EXTERNAL (decl)
1213 || DECL_REGISTER (decl));
1215 /* And that we were not given a type or a label. */
1216 gcc_assert (TREE_CODE (decl) != TYPE_DECL
1217 && TREE_CODE (decl) != LABEL_DECL);
1219 /* For a duplicate declaration, we can be called twice on the
1220 same DECL node. Don't discard the RTL already made. */
1221 if (DECL_RTL_SET_P (decl))
1223 /* If the old RTL had the wrong mode, fix the mode. */
1224 x = DECL_RTL (decl);
1225 if (GET_MODE (x) != DECL_MODE (decl))
1226 SET_DECL_RTL (decl, adjust_address_nv (x, DECL_MODE (decl), 0));
1228 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1229 return;
1231 /* ??? Another way to do this would be to maintain a hashed
1232 table of such critters. Instead of adding stuff to a DECL
1233 to give certain attributes to it, we could use an external
1234 hash map from DECL to set of attributes. */
1236 /* Let the target reassign the RTL if it wants.
1237 This is necessary, for example, when one machine specific
1238 decl attribute overrides another. */
1239 targetm.encode_section_info (decl, DECL_RTL (decl), false);
1241 /* If the symbol has a SYMBOL_REF_BLOCK field, update it based
1242 on the new decl information. */
1243 if (MEM_P (x)
1244 && GET_CODE (XEXP (x, 0)) == SYMBOL_REF
1245 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (x, 0)))
1246 change_symbol_block (XEXP (x, 0), get_block_for_decl (decl));
1248 /* Make this function static known to the mudflap runtime. */
1249 if (flag_mudflap && TREE_CODE (decl) == VAR_DECL)
1250 mudflap_enqueue_decl (decl);
1252 return;
1255 /* If this variable belongs to the global constant pool, retrieve the
1256 pre-computed RTL or recompute it in LTO mode. */
1257 if (TREE_CODE (decl) == VAR_DECL && DECL_IN_CONSTANT_POOL (decl))
1259 SET_DECL_RTL (decl, output_constant_def (DECL_INITIAL (decl), 1));
1260 return;
1263 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
1265 if (name[0] != '*' && TREE_CODE (decl) != FUNCTION_DECL
1266 && DECL_REGISTER (decl))
1268 error ("register name not specified for %q+D", decl);
1270 else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1272 const char *asmspec = name+1;
1273 enum machine_mode mode = DECL_MODE (decl);
1274 reg_number = decode_reg_name (asmspec);
1275 /* First detect errors in declaring global registers. */
1276 if (reg_number == -1)
1277 error ("register name not specified for %q+D", decl);
1278 else if (reg_number < 0)
1279 error ("invalid register name for %q+D", decl);
1280 else if (mode == BLKmode)
1281 error ("data type of %q+D isn%'t suitable for a register",
1282 decl);
1283 else if (!in_hard_reg_set_p (accessible_reg_set, mode, reg_number))
1284 error ("the register specified for %q+D cannot be accessed"
1285 " by the current target", decl);
1286 else if (!in_hard_reg_set_p (operand_reg_set, mode, reg_number))
1287 error ("the register specified for %q+D is not general enough"
1288 " to be used as a register variable", decl);
1289 else if (!HARD_REGNO_MODE_OK (reg_number, mode))
1290 error ("register specified for %q+D isn%'t suitable for data type",
1291 decl);
1292 /* Now handle properly declared static register variables. */
1293 else
1295 int nregs;
1297 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
1299 DECL_INITIAL (decl) = 0;
1300 error ("global register variable has initial value");
1302 if (TREE_THIS_VOLATILE (decl))
1303 warning (OPT_Wvolatile_register_var,
1304 "optimization may eliminate reads and/or "
1305 "writes to register variables");
1307 /* If the user specified one of the eliminables registers here,
1308 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
1309 confused with that register and be eliminated. This usage is
1310 somewhat suspect... */
1312 SET_DECL_RTL (decl, gen_rtx_raw_REG (mode, reg_number));
1313 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
1314 REG_USERVAR_P (DECL_RTL (decl)) = 1;
1316 if (TREE_STATIC (decl))
1318 /* Make this register global, so not usable for anything
1319 else. */
1320 #ifdef ASM_DECLARE_REGISTER_GLOBAL
1321 name = IDENTIFIER_POINTER (DECL_NAME (decl));
1322 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
1323 #endif
1324 nregs = hard_regno_nregs[reg_number][mode];
1325 while (nregs > 0)
1326 globalize_reg (decl, reg_number + --nregs);
1329 /* As a register variable, it has no section. */
1330 return;
1333 /* Now handle ordinary static variables and functions (in memory).
1334 Also handle vars declared register invalidly. */
1335 else if (name[0] == '*')
1337 #ifdef REGISTER_PREFIX
1338 if (strlen (REGISTER_PREFIX) != 0)
1340 reg_number = decode_reg_name (name);
1341 if (reg_number >= 0 || reg_number == -3)
1342 error ("register name given for non-register variable %q+D", decl);
1344 #endif
1347 /* Specifying a section attribute on a variable forces it into a
1348 non-.bss section, and thus it cannot be common. */
1349 /* FIXME: In general this code should not be necessary because
1350 visibility pass is doing the same work. But notice_global_symbol
1351 is called early and it needs to make DECL_RTL to get the name.
1352 we take care of recomputing the DECL_RTL after visibility is changed. */
1353 if (TREE_CODE (decl) == VAR_DECL
1354 && DECL_SECTION_NAME (decl) != NULL_TREE
1355 && DECL_INITIAL (decl) == NULL_TREE
1356 && DECL_COMMON (decl))
1357 DECL_COMMON (decl) = 0;
1359 /* Variables can't be both common and weak. */
1360 if (TREE_CODE (decl) == VAR_DECL && DECL_WEAK (decl))
1361 DECL_COMMON (decl) = 0;
1363 if (use_object_blocks_p () && use_blocks_for_decl_p (decl))
1364 x = create_block_symbol (name, get_block_for_decl (decl), -1);
1365 else
1367 enum machine_mode address_mode = Pmode;
1368 if (TREE_TYPE (decl) != error_mark_node)
1370 addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1371 address_mode = targetm.addr_space.address_mode (as);
1373 x = gen_rtx_SYMBOL_REF (address_mode, name);
1375 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
1376 SET_SYMBOL_REF_DECL (x, decl);
1378 x = gen_rtx_MEM (DECL_MODE (decl), x);
1379 if (TREE_CODE (decl) != FUNCTION_DECL)
1380 set_mem_attributes (x, decl, 1);
1381 SET_DECL_RTL (decl, x);
1383 /* Optionally set flags or add text to the name to record information
1384 such as that it is a function name.
1385 If the name is changed, the macro ASM_OUTPUT_LABELREF
1386 will have to know how to strip this information. */
1387 targetm.encode_section_info (decl, DECL_RTL (decl), true);
1389 /* Make this function static known to the mudflap runtime. */
1390 if (flag_mudflap && TREE_CODE (decl) == VAR_DECL)
1391 mudflap_enqueue_decl (decl);
1394 /* Like make_decl_rtl, but inhibit creation of new alias sets when
1395 calling make_decl_rtl. Also, reset DECL_RTL before returning the
1396 rtl. */
1399 make_decl_rtl_for_debug (tree decl)
1401 unsigned int save_aliasing_flag, save_mudflap_flag;
1402 rtx rtl;
1404 if (DECL_RTL_SET_P (decl))
1405 return DECL_RTL (decl);
1407 /* Kludge alert! Somewhere down the call chain, make_decl_rtl will
1408 call new_alias_set. If running with -fcompare-debug, sometimes
1409 we do not want to create alias sets that will throw the alias
1410 numbers off in the comparison dumps. So... clearing
1411 flag_strict_aliasing will keep new_alias_set() from creating a
1412 new set. It is undesirable to register decl with mudflap
1413 in this case as well. */
1414 save_aliasing_flag = flag_strict_aliasing;
1415 flag_strict_aliasing = 0;
1416 save_mudflap_flag = flag_mudflap;
1417 flag_mudflap = 0;
1419 rtl = DECL_RTL (decl);
1420 /* Reset DECL_RTL back, as various parts of the compiler expects
1421 DECL_RTL set meaning it is actually going to be output. */
1422 SET_DECL_RTL (decl, NULL);
1424 flag_strict_aliasing = save_aliasing_flag;
1425 flag_mudflap = save_mudflap_flag;
1427 return rtl;
1430 /* Output a string of literal assembler code
1431 for an `asm' keyword used between functions. */
1433 void
1434 assemble_asm (tree string)
1436 const char *p;
1437 app_enable ();
1439 if (TREE_CODE (string) == ADDR_EXPR)
1440 string = TREE_OPERAND (string, 0);
1442 p = TREE_STRING_POINTER (string);
1443 fprintf (asm_out_file, "%s%s\n", p[0] == '\t' ? "" : "\t", p);
1446 /* Write the address of the entity given by SYMBOL to SEC. */
1447 void
1448 assemble_addr_to_section (rtx symbol, section *sec)
1450 switch_to_section (sec);
1451 assemble_align (POINTER_SIZE);
1452 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1455 /* Return the numbered .ctors.N (if CONSTRUCTOR_P) or .dtors.N (if
1456 not) section for PRIORITY. */
1457 section *
1458 get_cdtor_priority_section (int priority, bool constructor_p)
1460 char buf[16];
1462 /* ??? This only works reliably with the GNU linker. */
1463 sprintf (buf, "%s.%.5u",
1464 constructor_p ? ".ctors" : ".dtors",
1465 /* Invert the numbering so the linker puts us in the proper
1466 order; constructors are run from right to left, and the
1467 linker sorts in increasing order. */
1468 MAX_INIT_PRIORITY - priority);
1469 return get_section (buf, SECTION_WRITE, NULL);
1472 void
1473 default_named_section_asm_out_destructor (rtx symbol, int priority)
1475 section *sec;
1477 if (priority != DEFAULT_INIT_PRIORITY)
1478 sec = get_cdtor_priority_section (priority,
1479 /*constructor_p=*/false);
1480 else
1481 sec = get_section (".dtors", SECTION_WRITE, NULL);
1483 assemble_addr_to_section (symbol, sec);
1486 #ifdef DTORS_SECTION_ASM_OP
1487 void
1488 default_dtor_section_asm_out_destructor (rtx symbol,
1489 int priority ATTRIBUTE_UNUSED)
1491 assemble_addr_to_section (symbol, dtors_section);
1493 #endif
1495 void
1496 default_named_section_asm_out_constructor (rtx symbol, int priority)
1498 section *sec;
1500 if (priority != DEFAULT_INIT_PRIORITY)
1501 sec = get_cdtor_priority_section (priority,
1502 /*constructor_p=*/true);
1503 else
1504 sec = get_section (".ctors", SECTION_WRITE, NULL);
1506 assemble_addr_to_section (symbol, sec);
1509 #ifdef CTORS_SECTION_ASM_OP
1510 void
1511 default_ctor_section_asm_out_constructor (rtx symbol,
1512 int priority ATTRIBUTE_UNUSED)
1514 assemble_addr_to_section (symbol, ctors_section);
1516 #endif
1518 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1519 a nonzero value if the constant pool should be output before the
1520 start of the function, or a zero value if the pool should output
1521 after the end of the function. The default is to put it before the
1522 start. */
1524 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1525 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1526 #endif
1528 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1529 to be output to assembler.
1530 Set first_global_object_name and weak_global_object_name as appropriate. */
1532 void
1533 notice_global_symbol (tree decl)
1535 const char **type = &first_global_object_name;
1537 if (first_global_object_name
1538 || !TREE_PUBLIC (decl)
1539 || DECL_EXTERNAL (decl)
1540 || !DECL_NAME (decl)
1541 || (TREE_CODE (decl) != FUNCTION_DECL
1542 && (TREE_CODE (decl) != VAR_DECL
1543 || (DECL_COMMON (decl)
1544 && (DECL_INITIAL (decl) == 0
1545 || DECL_INITIAL (decl) == error_mark_node))))
1546 || !MEM_P (DECL_RTL (decl)))
1547 return;
1549 /* We win when global object is found, but it is useful to know about weak
1550 symbol as well so we can produce nicer unique names. */
1551 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl) || flag_shlib)
1552 type = &weak_global_object_name;
1554 if (!*type)
1556 const char *p;
1557 const char *name;
1558 rtx decl_rtl = DECL_RTL (decl);
1560 p = targetm.strip_name_encoding (XSTR (XEXP (decl_rtl, 0), 0));
1561 name = ggc_strdup (p);
1563 *type = name;
1567 /* If not using flag_reorder_blocks_and_partition, decide early whether the
1568 current function goes into the cold section, so that targets can use
1569 current_function_section during RTL expansion. DECL describes the
1570 function. */
1572 void
1573 decide_function_section (tree decl)
1575 first_function_block_is_cold = false;
1577 if (flag_reorder_blocks_and_partition)
1578 /* We will decide in assemble_start_function. */
1579 return;
1581 if (DECL_SECTION_NAME (decl))
1583 struct cgraph_node *node = cgraph_get_node (current_function_decl);
1584 /* Calls to function_section rely on first_function_block_is_cold
1585 being accurate. */
1586 first_function_block_is_cold = (node
1587 && node->frequency
1588 == NODE_FREQUENCY_UNLIKELY_EXECUTED);
1591 in_cold_section_p = first_function_block_is_cold;
1594 /* Output assembler code for the constant pool of a function and associated
1595 with defining the name of the function. DECL describes the function.
1596 NAME is the function's name. For the constant pool, we use the current
1597 constant pool data. */
1599 void
1600 assemble_start_function (tree decl, const char *fnname)
1602 int align;
1603 char tmp_label[100];
1604 bool hot_label_written = false;
1606 if (flag_reorder_blocks_and_partition)
1608 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTB", const_labelno);
1609 crtl->subsections.hot_section_label = ggc_strdup (tmp_label);
1610 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDB", const_labelno);
1611 crtl->subsections.cold_section_label = ggc_strdup (tmp_label);
1612 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTE", const_labelno);
1613 crtl->subsections.hot_section_end_label = ggc_strdup (tmp_label);
1614 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDE", const_labelno);
1615 crtl->subsections.cold_section_end_label = ggc_strdup (tmp_label);
1616 const_labelno++;
1618 else
1620 crtl->subsections.hot_section_label = NULL;
1621 crtl->subsections.cold_section_label = NULL;
1622 crtl->subsections.hot_section_end_label = NULL;
1623 crtl->subsections.cold_section_end_label = NULL;
1626 /* The following code does not need preprocessing in the assembler. */
1628 app_disable ();
1630 if (CONSTANT_POOL_BEFORE_FUNCTION)
1631 output_constant_pool (fnname, decl);
1633 /* Make sure the not and cold text (code) sections are properly
1634 aligned. This is necessary here in the case where the function
1635 has both hot and cold sections, because we don't want to re-set
1636 the alignment when the section switch happens mid-function. */
1638 if (flag_reorder_blocks_and_partition)
1640 first_function_block_is_cold = false;
1642 switch_to_section (unlikely_text_section ());
1643 assemble_align (DECL_ALIGN (decl));
1644 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_label);
1646 /* When the function starts with a cold section, we need to explicitly
1647 align the hot section and write out the hot section label.
1648 But if the current function is a thunk, we do not have a CFG. */
1649 if (!cfun->is_thunk
1650 && BB_PARTITION (ENTRY_BLOCK_PTR->next_bb) == BB_COLD_PARTITION)
1652 switch_to_section (text_section);
1653 assemble_align (DECL_ALIGN (decl));
1654 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1655 hot_label_written = true;
1656 first_function_block_is_cold = true;
1658 in_cold_section_p = first_function_block_is_cold;
1662 /* Switch to the correct text section for the start of the function. */
1664 switch_to_section (function_section (decl));
1665 if (flag_reorder_blocks_and_partition
1666 && !hot_label_written)
1667 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1669 /* Tell assembler to move to target machine's alignment for functions. */
1670 align = floor_log2 (DECL_ALIGN (decl) / BITS_PER_UNIT);
1671 if (align > 0)
1673 ASM_OUTPUT_ALIGN (asm_out_file, align);
1676 /* Handle a user-specified function alignment.
1677 Note that we still need to align to DECL_ALIGN, as above,
1678 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1679 if (! DECL_USER_ALIGN (decl)
1680 && align_functions_log > align
1681 && optimize_function_for_speed_p (cfun))
1683 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1684 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1685 align_functions_log, align_functions - 1);
1686 #else
1687 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1688 #endif
1691 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1692 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1693 #endif
1695 if (!DECL_IGNORED_P (decl))
1696 (*debug_hooks->begin_function) (decl);
1698 /* Make function name accessible from other files, if appropriate. */
1700 if (TREE_PUBLIC (decl))
1702 notice_global_symbol (decl);
1704 globalize_decl (decl);
1706 maybe_assemble_visibility (decl);
1709 if (DECL_PRESERVE_P (decl))
1710 targetm.asm_out.mark_decl_preserved (fnname);
1712 /* Do any machine/system dependent processing of the function name. */
1713 #ifdef ASM_DECLARE_FUNCTION_NAME
1714 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1715 #else
1716 /* Standard thing is just output label for the function. */
1717 ASM_OUTPUT_FUNCTION_LABEL (asm_out_file, fnname, current_function_decl);
1718 #endif /* ASM_DECLARE_FUNCTION_NAME */
1720 if (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (decl)))
1721 saw_no_split_stack = true;
1724 /* Output assembler code associated with defining the size of the
1725 function. DECL describes the function. NAME is the function's name. */
1727 void
1728 assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED)
1730 #ifdef ASM_DECLARE_FUNCTION_SIZE
1731 /* We could have switched section in the middle of the function. */
1732 if (flag_reorder_blocks_and_partition)
1733 switch_to_section (function_section (decl));
1734 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1735 #endif
1736 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1738 output_constant_pool (fnname, decl);
1739 switch_to_section (function_section (decl)); /* need to switch back */
1741 /* Output labels for end of hot/cold text sections (to be used by
1742 debug info.) */
1743 if (flag_reorder_blocks_and_partition)
1745 section *save_text_section;
1747 save_text_section = in_section;
1748 switch_to_section (unlikely_text_section ());
1749 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label);
1750 if (first_function_block_is_cold)
1751 switch_to_section (text_section);
1752 else
1753 switch_to_section (function_section (decl));
1754 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label);
1755 switch_to_section (save_text_section);
1759 /* Assemble code to leave SIZE bytes of zeros. */
1761 void
1762 assemble_zeros (unsigned HOST_WIDE_INT size)
1764 /* Do no output if -fsyntax-only. */
1765 if (flag_syntax_only)
1766 return;
1768 #ifdef ASM_NO_SKIP_IN_TEXT
1769 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1770 so we must output 0s explicitly in the text section. */
1771 if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0)
1773 unsigned HOST_WIDE_INT i;
1774 for (i = 0; i < size; i++)
1775 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1777 else
1778 #endif
1779 if (size > 0)
1780 ASM_OUTPUT_SKIP (asm_out_file, size);
1783 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1785 void
1786 assemble_align (int align)
1788 if (align > BITS_PER_UNIT)
1790 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1794 /* Assemble a string constant with the specified C string as contents. */
1796 void
1797 assemble_string (const char *p, int size)
1799 int pos = 0;
1800 int maximum = 2000;
1802 /* If the string is very long, split it up. */
1804 while (pos < size)
1806 int thissize = size - pos;
1807 if (thissize > maximum)
1808 thissize = maximum;
1810 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1812 pos += thissize;
1813 p += thissize;
1818 /* A noswitch_section_callback for lcomm_section. */
1820 static bool
1821 emit_local (tree decl ATTRIBUTE_UNUSED,
1822 const char *name ATTRIBUTE_UNUSED,
1823 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1824 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1826 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1827 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name,
1828 size, DECL_ALIGN (decl));
1829 return true;
1830 #elif defined ASM_OUTPUT_ALIGNED_LOCAL
1831 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, DECL_ALIGN (decl));
1832 return true;
1833 #else
1834 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1835 return false;
1836 #endif
1839 /* A noswitch_section_callback for bss_noswitch_section. */
1841 #if defined ASM_OUTPUT_ALIGNED_BSS
1842 static bool
1843 emit_bss (tree decl ATTRIBUTE_UNUSED,
1844 const char *name ATTRIBUTE_UNUSED,
1845 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1846 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1848 #if defined ASM_OUTPUT_ALIGNED_BSS
1849 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size,
1850 get_variable_align (decl));
1851 return true;
1852 #endif
1854 #endif
1856 /* A noswitch_section_callback for comm_section. */
1858 static bool
1859 emit_common (tree decl ATTRIBUTE_UNUSED,
1860 const char *name ATTRIBUTE_UNUSED,
1861 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1862 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1864 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1865 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name,
1866 size, get_variable_align (decl));
1867 return true;
1868 #elif defined ASM_OUTPUT_ALIGNED_COMMON
1869 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size,
1870 get_variable_align (decl));
1871 return true;
1872 #else
1873 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
1874 return false;
1875 #endif
1878 /* A noswitch_section_callback for tls_comm_section. */
1880 static bool
1881 emit_tls_common (tree decl ATTRIBUTE_UNUSED,
1882 const char *name ATTRIBUTE_UNUSED,
1883 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1884 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1886 #ifdef ASM_OUTPUT_TLS_COMMON
1887 ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size);
1888 return true;
1889 #else
1890 sorry ("thread-local COMMON data not implemented");
1891 return true;
1892 #endif
1895 /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT.
1896 NAME is the name of DECL's SYMBOL_REF. */
1898 static void
1899 assemble_noswitch_variable (tree decl, const char *name, section *sect,
1900 unsigned int align)
1902 unsigned HOST_WIDE_INT size, rounded;
1904 size = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
1905 rounded = size;
1907 if (flag_asan && asan_protect_global (decl))
1908 size += asan_red_zone_size (size);
1910 /* Don't allocate zero bytes of common,
1911 since that means "undefined external" in the linker. */
1912 if (size == 0)
1913 rounded = 1;
1915 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1916 so that each uninitialized object starts on such a boundary. */
1917 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
1918 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1919 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1921 if (!sect->noswitch.callback (decl, name, size, rounded)
1922 && (unsigned HOST_WIDE_INT) (align / BITS_PER_UNIT) > rounded)
1923 warning (0, "requested alignment for %q+D is greater than "
1924 "implemented alignment of %wu", decl, rounded);
1927 /* A subroutine of assemble_variable. Output the label and contents of
1928 DECL, whose address is a SYMBOL_REF with name NAME. DONT_OUTPUT_DATA
1929 is as for assemble_variable. */
1931 static void
1932 assemble_variable_contents (tree decl, const char *name,
1933 bool dont_output_data)
1935 /* Do any machine/system dependent processing of the object. */
1936 #ifdef ASM_DECLARE_OBJECT_NAME
1937 last_assemble_variable_decl = decl;
1938 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
1939 #else
1940 /* Standard thing is just output label for the object. */
1941 ASM_OUTPUT_LABEL (asm_out_file, name);
1942 #endif /* ASM_DECLARE_OBJECT_NAME */
1944 if (!dont_output_data)
1946 if (DECL_INITIAL (decl)
1947 && DECL_INITIAL (decl) != error_mark_node
1948 && !initializer_zerop (DECL_INITIAL (decl)))
1949 /* Output the actual data. */
1950 output_constant (DECL_INITIAL (decl),
1951 tree_low_cst (DECL_SIZE_UNIT (decl), 1),
1952 get_variable_align (decl));
1953 else
1954 /* Leave space for it. */
1955 assemble_zeros (tree_low_cst (DECL_SIZE_UNIT (decl), 1));
1959 /* Assemble everything that is needed for a variable or function declaration.
1960 Not used for automatic variables, and not used for function definitions.
1961 Should not be called for variables of incomplete structure type.
1963 TOP_LEVEL is nonzero if this variable has file scope.
1964 AT_END is nonzero if this is the special handling, at end of compilation,
1965 to define things that have had only tentative definitions.
1966 DONT_OUTPUT_DATA if nonzero means don't actually output the
1967 initial value (that will be done by the caller). */
1969 void
1970 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
1971 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
1973 const char *name;
1974 rtx decl_rtl, symbol;
1975 section *sect;
1976 unsigned int align;
1977 bool asan_protected = false;
1979 /* This function is supposed to handle VARIABLES. Ensure we have one. */
1980 gcc_assert (TREE_CODE (decl) == VAR_DECL);
1982 /* Emulated TLS had better not get this far. */
1983 gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl));
1985 last_assemble_variable_decl = 0;
1987 /* Normally no need to say anything here for external references,
1988 since assemble_external is called by the language-specific code
1989 when a declaration is first seen. */
1991 if (DECL_EXTERNAL (decl))
1992 return;
1994 /* Do nothing for global register variables. */
1995 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
1997 TREE_ASM_WRITTEN (decl) = 1;
1998 return;
2001 /* If type was incomplete when the variable was declared,
2002 see if it is complete now. */
2004 if (DECL_SIZE (decl) == 0)
2005 layout_decl (decl, 0);
2007 /* Still incomplete => don't allocate it; treat the tentative defn
2008 (which is what it must have been) as an `extern' reference. */
2010 if (!dont_output_data && DECL_SIZE (decl) == 0)
2012 error ("storage size of %q+D isn%'t known", decl);
2013 TREE_ASM_WRITTEN (decl) = 1;
2014 return;
2017 /* The first declaration of a variable that comes through this function
2018 decides whether it is global (in C, has external linkage)
2019 or local (in C, has internal linkage). So do nothing more
2020 if this function has already run. */
2022 if (TREE_ASM_WRITTEN (decl))
2023 return;
2025 /* Make sure targetm.encode_section_info is invoked before we set
2026 ASM_WRITTEN. */
2027 decl_rtl = DECL_RTL (decl);
2029 TREE_ASM_WRITTEN (decl) = 1;
2031 /* Do no output if -fsyntax-only. */
2032 if (flag_syntax_only)
2033 return;
2035 if (! dont_output_data
2036 && ! valid_constant_size_p (DECL_SIZE_UNIT (decl)))
2038 error ("size of variable %q+D is too large", decl);
2039 return;
2042 gcc_assert (MEM_P (decl_rtl));
2043 gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF);
2044 symbol = XEXP (decl_rtl, 0);
2046 /* If this symbol belongs to the tree constant pool, output the constant
2047 if it hasn't already been written. */
2048 if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
2050 tree decl = SYMBOL_REF_DECL (symbol);
2051 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
2052 output_constant_def_contents (symbol);
2053 return;
2056 app_disable ();
2058 name = XSTR (symbol, 0);
2059 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
2060 notice_global_symbol (decl);
2062 /* Compute the alignment of this data. */
2064 align_variable (decl, dont_output_data);
2066 if (flag_asan
2067 && asan_protect_global (decl))
2069 asan_protected = true;
2070 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
2071 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
2074 set_mem_align (decl_rtl, DECL_ALIGN (decl));
2076 align = get_variable_align (decl);
2078 if (TREE_PUBLIC (decl))
2079 maybe_assemble_visibility (decl);
2081 if (DECL_PRESERVE_P (decl))
2082 targetm.asm_out.mark_decl_preserved (name);
2084 /* First make the assembler name(s) global if appropriate. */
2085 sect = get_variable_section (decl, false);
2086 if (TREE_PUBLIC (decl)
2087 && (sect->common.flags & SECTION_COMMON) == 0)
2088 globalize_decl (decl);
2090 /* Output any data that we will need to use the address of. */
2091 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
2092 output_addressed_constants (DECL_INITIAL (decl));
2094 /* dbxout.c needs to know this. */
2095 if (sect && (sect->common.flags & SECTION_CODE) != 0)
2096 DECL_IN_TEXT_SECTION (decl) = 1;
2098 /* If the decl is part of an object_block, make sure that the decl
2099 has been positioned within its block, but do not write out its
2100 definition yet. output_object_blocks will do that later. */
2101 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
2103 gcc_assert (!dont_output_data);
2104 place_block_symbol (symbol);
2106 else if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
2107 assemble_noswitch_variable (decl, name, sect, align);
2108 else
2110 switch_to_section (sect);
2111 if (align > BITS_PER_UNIT)
2112 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2113 assemble_variable_contents (decl, name, dont_output_data);
2114 if (asan_protected)
2116 unsigned HOST_WIDE_INT int size
2117 = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
2118 assemble_zeros (asan_red_zone_size (size));
2123 /* Return 1 if type TYPE contains any pointers. */
2125 static int
2126 contains_pointers_p (tree type)
2128 switch (TREE_CODE (type))
2130 case POINTER_TYPE:
2131 case REFERENCE_TYPE:
2132 /* I'm not sure whether OFFSET_TYPE needs this treatment,
2133 so I'll play safe and return 1. */
2134 case OFFSET_TYPE:
2135 return 1;
2137 case RECORD_TYPE:
2138 case UNION_TYPE:
2139 case QUAL_UNION_TYPE:
2141 tree fields;
2142 /* For a type that has fields, see if the fields have pointers. */
2143 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2144 if (TREE_CODE (fields) == FIELD_DECL
2145 && contains_pointers_p (TREE_TYPE (fields)))
2146 return 1;
2147 return 0;
2150 case ARRAY_TYPE:
2151 /* An array type contains pointers if its element type does. */
2152 return contains_pointers_p (TREE_TYPE (type));
2154 default:
2155 return 0;
2159 /* We delay assemble_external processing until
2160 the compilation unit is finalized. This is the best we can do for
2161 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2162 it all the way to final. See PR 17982 for further discussion. */
2163 static GTY(()) tree pending_assemble_externals;
2165 #ifdef ASM_OUTPUT_EXTERNAL
2166 /* Some targets delay some output to final using TARGET_ASM_FILE_END.
2167 As a result, assemble_external can be called after the list of externals
2168 is processed and the pointer set destroyed. */
2169 static bool pending_assemble_externals_processed;
2171 /* Avoid O(external_decls**2) lookups in the pending_assemble_externals
2172 TREE_LIST in assemble_external. */
2173 static struct pointer_set_t *pending_assemble_externals_set;
2175 /* True if DECL is a function decl for which no out-of-line copy exists.
2176 It is assumed that DECL's assembler name has been set. */
2178 static bool
2179 incorporeal_function_p (tree decl)
2181 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
2183 const char *name;
2185 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2186 && (DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA
2187 || DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA_WITH_ALIGN))
2188 return true;
2190 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2191 /* Atomic or sync builtins which have survived this far will be
2192 resolved externally and therefore are not incorporeal. */
2193 if (strncmp (name, "__builtin_", 10) == 0)
2194 return true;
2196 return false;
2199 /* Actually do the tests to determine if this is necessary, and invoke
2200 ASM_OUTPUT_EXTERNAL. */
2201 static void
2202 assemble_external_real (tree decl)
2204 rtx rtl = DECL_RTL (decl);
2206 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2207 && !SYMBOL_REF_USED (XEXP (rtl, 0))
2208 && !incorporeal_function_p (decl))
2210 /* Some systems do require some output. */
2211 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2212 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2215 #endif
2217 void
2218 process_pending_assemble_externals (void)
2220 #ifdef ASM_OUTPUT_EXTERNAL
2221 tree list;
2222 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2223 assemble_external_real (TREE_VALUE (list));
2225 pending_assemble_externals = 0;
2226 pending_assemble_externals_processed = true;
2227 pointer_set_destroy (pending_assemble_externals_set);
2228 #endif
2231 /* This TREE_LIST contains any weak symbol declarations waiting
2232 to be emitted. */
2233 static GTY(()) tree weak_decls;
2235 /* Output something to declare an external symbol to the assembler,
2236 and qualifiers such as weakness. (Most assemblers don't need
2237 extern declaration, so we normally output nothing.) Do nothing if
2238 DECL is not external. */
2240 void
2241 assemble_external (tree decl ATTRIBUTE_UNUSED)
2243 /* Make sure that the ASM_OUT_FILE is open.
2244 If it's not, we should not be calling this function. */
2245 gcc_assert (asm_out_file);
2247 /* In a perfect world, the following condition would be true.
2248 Sadly, the Java and Go front ends emit assembly *from the front end*,
2249 bypassing the call graph. See PR52739. Fix before GCC 4.8. */
2250 #if 0
2251 /* This function should only be called if we are expanding, or have
2252 expanded, to RTL.
2253 Ideally, only final.c would be calling this function, but it is
2254 not clear whether that would break things somehow. See PR 17982
2255 for further discussion. */
2256 gcc_assert (cgraph_state == CGRAPH_STATE_EXPANSION
2257 || cgraph_state == CGRAPH_STATE_FINISHED);
2258 #endif
2260 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2261 return;
2263 /* We want to output annotation for weak and external symbols at
2264 very last to check if they are references or not. */
2266 if (TARGET_SUPPORTS_WEAK
2267 && DECL_WEAK (decl)
2268 /* TREE_STATIC is a weird and abused creature which is not
2269 generally the right test for whether an entity has been
2270 locally emitted, inlined or otherwise not-really-extern, but
2271 for declarations that can be weak, it happens to be
2272 match. */
2273 && !TREE_STATIC (decl)
2274 && lookup_attribute ("weak", DECL_ATTRIBUTES (decl))
2275 && value_member (decl, weak_decls) == NULL_TREE)
2276 weak_decls = tree_cons (NULL, decl, weak_decls);
2278 #ifdef ASM_OUTPUT_EXTERNAL
2279 if (pending_assemble_externals_processed)
2281 assemble_external_real (decl);
2282 return;
2285 if (! pointer_set_insert (pending_assemble_externals_set, decl))
2286 pending_assemble_externals = tree_cons (NULL, decl,
2287 pending_assemble_externals);
2288 #endif
2291 /* Similar, for calling a library function FUN. */
2293 void
2294 assemble_external_libcall (rtx fun)
2296 /* Declare library function name external when first used, if nec. */
2297 if (! SYMBOL_REF_USED (fun))
2299 SYMBOL_REF_USED (fun) = 1;
2300 targetm.asm_out.external_libcall (fun);
2304 /* Assemble a label named NAME. */
2306 void
2307 assemble_label (FILE *file, const char *name)
2309 ASM_OUTPUT_LABEL (file, name);
2312 /* Set the symbol_referenced flag for ID. */
2313 void
2314 mark_referenced (tree id)
2316 TREE_SYMBOL_REFERENCED (id) = 1;
2319 /* Set the symbol_referenced flag for DECL and notify callgraph. */
2320 void
2321 mark_decl_referenced (tree decl)
2323 if (TREE_CODE (decl) == FUNCTION_DECL)
2325 /* Extern inline functions don't become needed when referenced.
2326 If we know a method will be emitted in other TU and no new
2327 functions can be marked reachable, just use the external
2328 definition. */
2329 struct cgraph_node *node = cgraph_get_create_node (decl);
2330 if (!DECL_EXTERNAL (decl)
2331 && !node->symbol.definition)
2332 cgraph_mark_force_output_node (node);
2334 else if (TREE_CODE (decl) == VAR_DECL)
2336 struct varpool_node *node = varpool_node_for_decl (decl);
2337 /* C++ frontend use mark_decl_references to force COMDAT variables
2338 to be output that might appear dead otherwise. */
2339 node->symbol.force_output = true;
2341 /* else do nothing - we can get various sorts of CST nodes here,
2342 which do not need to be marked. */
2346 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS
2347 until we find an identifier that is not itself a transparent alias.
2348 Modify the alias passed to it by reference (and all aliases on the
2349 way to the ultimate target), such that they do not have to be
2350 followed again, and return the ultimate target of the alias
2351 chain. */
2353 static inline tree
2354 ultimate_transparent_alias_target (tree *alias)
2356 tree target = *alias;
2358 if (IDENTIFIER_TRANSPARENT_ALIAS (target))
2360 gcc_assert (TREE_CHAIN (target));
2361 target = ultimate_transparent_alias_target (&TREE_CHAIN (target));
2362 gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target)
2363 && ! TREE_CHAIN (target));
2364 *alias = target;
2367 return target;
2370 /* Output to FILE (an assembly file) a reference to NAME. If NAME
2371 starts with a *, the rest of NAME is output verbatim. Otherwise
2372 NAME is transformed in a target-specific way (usually by the
2373 addition of an underscore). */
2375 void
2376 assemble_name_raw (FILE *file, const char *name)
2378 if (name[0] == '*')
2379 fputs (&name[1], file);
2380 else
2381 ASM_OUTPUT_LABELREF (file, name);
2384 /* Like assemble_name_raw, but should be used when NAME might refer to
2385 an entity that is also represented as a tree (like a function or
2386 variable). If NAME does refer to such an entity, that entity will
2387 be marked as referenced. */
2389 void
2390 assemble_name (FILE *file, const char *name)
2392 const char *real_name;
2393 tree id;
2395 real_name = targetm.strip_name_encoding (name);
2397 id = maybe_get_identifier (real_name);
2398 if (id)
2400 tree id_orig = id;
2402 mark_referenced (id);
2403 ultimate_transparent_alias_target (&id);
2404 if (id != id_orig)
2405 name = IDENTIFIER_POINTER (id);
2406 gcc_assert (! TREE_CHAIN (id));
2409 assemble_name_raw (file, name);
2412 /* Allocate SIZE bytes writable static space with a gensym name
2413 and return an RTX to refer to its address. */
2416 assemble_static_space (unsigned HOST_WIDE_INT size)
2418 char name[12];
2419 const char *namestring;
2420 rtx x;
2422 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2423 ++const_labelno;
2424 namestring = ggc_strdup (name);
2426 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2427 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2429 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2430 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2431 BIGGEST_ALIGNMENT);
2432 #else
2433 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2434 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2435 #else
2437 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2438 so that each uninitialized object starts on such a boundary. */
2439 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2440 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2441 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2442 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2443 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2444 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2446 #endif
2447 #endif
2448 return x;
2451 /* Assemble the static constant template for function entry trampolines.
2452 This is done at most once per compilation.
2453 Returns an RTX for the address of the template. */
2455 static GTY(()) rtx initial_trampoline;
2458 assemble_trampoline_template (void)
2460 char label[256];
2461 const char *name;
2462 int align;
2463 rtx symbol;
2465 gcc_assert (targetm.asm_out.trampoline_template != NULL);
2467 if (initial_trampoline)
2468 return initial_trampoline;
2470 /* By default, put trampoline templates in read-only data section. */
2472 #ifdef TRAMPOLINE_SECTION
2473 switch_to_section (TRAMPOLINE_SECTION);
2474 #else
2475 switch_to_section (readonly_data_section);
2476 #endif
2478 /* Write the assembler code to define one. */
2479 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2480 if (align > 0)
2481 ASM_OUTPUT_ALIGN (asm_out_file, align);
2483 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2484 targetm.asm_out.trampoline_template (asm_out_file);
2486 /* Record the rtl to refer to it. */
2487 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2488 name = ggc_strdup (label);
2489 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2490 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2492 initial_trampoline = gen_const_mem (BLKmode, symbol);
2493 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2494 set_mem_size (initial_trampoline, TRAMPOLINE_SIZE);
2496 return initial_trampoline;
2499 /* A and B are either alignments or offsets. Return the minimum alignment
2500 that may be assumed after adding the two together. */
2502 static inline unsigned
2503 min_align (unsigned int a, unsigned int b)
2505 return (a | b) & -(a | b);
2508 /* Return the assembler directive for creating a given kind of integer
2509 object. SIZE is the number of bytes in the object and ALIGNED_P
2510 indicates whether it is known to be aligned. Return NULL if the
2511 assembly dialect has no such directive.
2513 The returned string should be printed at the start of a new line and
2514 be followed immediately by the object's initial value. */
2516 const char *
2517 integer_asm_op (int size, int aligned_p)
2519 struct asm_int_op *ops;
2521 if (aligned_p)
2522 ops = &targetm.asm_out.aligned_op;
2523 else
2524 ops = &targetm.asm_out.unaligned_op;
2526 switch (size)
2528 case 1:
2529 return targetm.asm_out.byte_op;
2530 case 2:
2531 return ops->hi;
2532 case 4:
2533 return ops->si;
2534 case 8:
2535 return ops->di;
2536 case 16:
2537 return ops->ti;
2538 default:
2539 return NULL;
2543 /* Use directive OP to assemble an integer object X. Print OP at the
2544 start of the line, followed immediately by the value of X. */
2546 void
2547 assemble_integer_with_op (const char *op, rtx x)
2549 fputs (op, asm_out_file);
2550 output_addr_const (asm_out_file, x);
2551 fputc ('\n', asm_out_file);
2554 /* The default implementation of the asm_out.integer target hook. */
2556 bool
2557 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2558 unsigned int size ATTRIBUTE_UNUSED,
2559 int aligned_p ATTRIBUTE_UNUSED)
2561 const char *op = integer_asm_op (size, aligned_p);
2562 /* Avoid GAS bugs for large values. Specifically negative values whose
2563 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2564 if (size > UNITS_PER_WORD && size > POINTER_SIZE / BITS_PER_UNIT)
2565 return false;
2566 return op && (assemble_integer_with_op (op, x), true);
2569 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2570 the alignment of the integer in bits. Return 1 if we were able to output
2571 the constant, otherwise 0. We must be able to output the constant,
2572 if FORCE is nonzero. */
2574 bool
2575 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2577 int aligned_p;
2579 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2581 /* See if the target hook can handle this kind of object. */
2582 if (targetm.asm_out.integer (x, size, aligned_p))
2583 return true;
2585 /* If the object is a multi-byte one, try splitting it up. Split
2586 it into words it if is multi-word, otherwise split it into bytes. */
2587 if (size > 1)
2589 enum machine_mode omode, imode;
2590 unsigned int subalign;
2591 unsigned int subsize, i;
2592 enum mode_class mclass;
2594 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2595 subalign = MIN (align, subsize * BITS_PER_UNIT);
2596 if (GET_CODE (x) == CONST_FIXED)
2597 mclass = GET_MODE_CLASS (GET_MODE (x));
2598 else
2599 mclass = MODE_INT;
2601 omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0);
2602 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0);
2604 for (i = 0; i < size; i += subsize)
2606 rtx partial = simplify_subreg (omode, x, imode, i);
2607 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2608 break;
2610 if (i == size)
2611 return true;
2613 /* If we've printed some of it, but not all of it, there's no going
2614 back now. */
2615 gcc_assert (!i);
2618 gcc_assert (!force);
2620 return false;
2623 void
2624 assemble_real (REAL_VALUE_TYPE d, enum machine_mode mode, unsigned int align)
2626 long data[4] = {0, 0, 0, 0};
2627 int i;
2628 int bitsize, nelts, nunits, units_per;
2630 /* This is hairy. We have a quantity of known size. real_to_target
2631 will put it into an array of *host* longs, 32 bits per element
2632 (even if long is more than 32 bits). We need to determine the
2633 number of array elements that are occupied (nelts) and the number
2634 of *target* min-addressable units that will be occupied in the
2635 object file (nunits). We cannot assume that 32 divides the
2636 mode's bitsize (size * BITS_PER_UNIT) evenly.
2638 size * BITS_PER_UNIT is used here to make sure that padding bits
2639 (which might appear at either end of the value; real_to_target
2640 will include the padding bits in its output array) are included. */
2642 nunits = GET_MODE_SIZE (mode);
2643 bitsize = nunits * BITS_PER_UNIT;
2644 nelts = CEIL (bitsize, 32);
2645 units_per = 32 / BITS_PER_UNIT;
2647 real_to_target (data, &d, mode);
2649 /* Put out the first word with the specified alignment. */
2650 assemble_integer (GEN_INT (data[0]), MIN (nunits, units_per), align, 1);
2651 nunits -= units_per;
2653 /* Subsequent words need only 32-bit alignment. */
2654 align = min_align (align, 32);
2656 for (i = 1; i < nelts; i++)
2658 assemble_integer (GEN_INT (data[i]), MIN (nunits, units_per), align, 1);
2659 nunits -= units_per;
2663 /* Given an expression EXP with a constant value,
2664 reduce it to the sum of an assembler symbol and an integer.
2665 Store them both in the structure *VALUE.
2666 EXP must be reducible. */
2668 struct addr_const {
2669 rtx base;
2670 HOST_WIDE_INT offset;
2673 static void
2674 decode_addr_const (tree exp, struct addr_const *value)
2676 tree target = TREE_OPERAND (exp, 0);
2677 int offset = 0;
2678 rtx x;
2680 while (1)
2682 if (TREE_CODE (target) == COMPONENT_REF
2683 && host_integerp (byte_position (TREE_OPERAND (target, 1)), 0))
2685 offset += int_byte_position (TREE_OPERAND (target, 1));
2686 target = TREE_OPERAND (target, 0);
2688 else if (TREE_CODE (target) == ARRAY_REF
2689 || TREE_CODE (target) == ARRAY_RANGE_REF)
2691 offset += (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (target)), 1)
2692 * tree_low_cst (TREE_OPERAND (target, 1), 0));
2693 target = TREE_OPERAND (target, 0);
2695 else if (TREE_CODE (target) == MEM_REF
2696 && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR)
2698 offset += mem_ref_offset (target).low;
2699 target = TREE_OPERAND (TREE_OPERAND (target, 0), 0);
2701 else if (TREE_CODE (target) == INDIRECT_REF
2702 && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR
2703 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0))
2704 == ADDR_EXPR)
2705 target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0);
2706 else
2707 break;
2710 switch (TREE_CODE (target))
2712 case VAR_DECL:
2713 case FUNCTION_DECL:
2714 x = DECL_RTL (target);
2715 break;
2717 case LABEL_DECL:
2718 x = gen_rtx_MEM (FUNCTION_MODE,
2719 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2720 break;
2722 case REAL_CST:
2723 case FIXED_CST:
2724 case STRING_CST:
2725 case COMPLEX_CST:
2726 case CONSTRUCTOR:
2727 case INTEGER_CST:
2728 x = output_constant_def (target, 1);
2729 break;
2731 default:
2732 gcc_unreachable ();
2735 gcc_assert (MEM_P (x));
2736 x = XEXP (x, 0);
2738 value->base = x;
2739 value->offset = offset;
2743 static GTY((param_is (struct constant_descriptor_tree)))
2744 htab_t const_desc_htab;
2746 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2748 /* Constant pool accessor function. */
2750 htab_t
2751 constant_pool_htab (void)
2753 return const_desc_htab;
2756 /* Compute a hash code for a constant expression. */
2758 static hashval_t
2759 const_desc_hash (const void *ptr)
2761 return ((const struct constant_descriptor_tree *)ptr)->hash;
2764 static hashval_t
2765 const_hash_1 (const tree exp)
2767 const char *p;
2768 hashval_t hi;
2769 int len, i;
2770 enum tree_code code = TREE_CODE (exp);
2772 /* Either set P and LEN to the address and len of something to hash and
2773 exit the switch or return a value. */
2775 switch (code)
2777 case INTEGER_CST:
2778 p = (char *) &TREE_INT_CST (exp);
2779 len = sizeof TREE_INT_CST (exp);
2780 break;
2782 case REAL_CST:
2783 return real_hash (TREE_REAL_CST_PTR (exp));
2785 case FIXED_CST:
2786 return fixed_hash (TREE_FIXED_CST_PTR (exp));
2788 case STRING_CST:
2789 p = TREE_STRING_POINTER (exp);
2790 len = TREE_STRING_LENGTH (exp);
2791 break;
2793 case COMPLEX_CST:
2794 return (const_hash_1 (TREE_REALPART (exp)) * 5
2795 + const_hash_1 (TREE_IMAGPART (exp)));
2797 case VECTOR_CST:
2799 unsigned i;
2801 hi = 7 + VECTOR_CST_NELTS (exp);
2803 for (i = 0; i < VECTOR_CST_NELTS (exp); ++i)
2804 hi = hi * 563 + const_hash_1 (VECTOR_CST_ELT (exp, i));
2806 return hi;
2809 case CONSTRUCTOR:
2811 unsigned HOST_WIDE_INT idx;
2812 tree value;
2814 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2816 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
2817 if (value)
2818 hi = hi * 603 + const_hash_1 (value);
2820 return hi;
2823 case ADDR_EXPR:
2824 case FDESC_EXPR:
2826 struct addr_const value;
2828 decode_addr_const (exp, &value);
2829 switch (GET_CODE (value.base))
2831 case SYMBOL_REF:
2832 /* Don't hash the address of the SYMBOL_REF;
2833 only use the offset and the symbol name. */
2834 hi = value.offset;
2835 p = XSTR (value.base, 0);
2836 for (i = 0; p[i] != 0; i++)
2837 hi = ((hi * 613) + (unsigned) (p[i]));
2838 break;
2840 case LABEL_REF:
2841 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13;
2842 break;
2844 default:
2845 gcc_unreachable ();
2848 return hi;
2850 case PLUS_EXPR:
2851 case POINTER_PLUS_EXPR:
2852 case MINUS_EXPR:
2853 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2854 + const_hash_1 (TREE_OPERAND (exp, 1)));
2856 CASE_CONVERT:
2857 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
2859 default:
2860 /* A language specific constant. Just hash the code. */
2861 return code;
2864 /* Compute hashing function. */
2865 hi = len;
2866 for (i = 0; i < len; i++)
2867 hi = ((hi * 613) + (unsigned) (p[i]));
2869 return hi;
2872 /* Wrapper of compare_constant, for the htab interface. */
2873 static int
2874 const_desc_eq (const void *p1, const void *p2)
2876 const struct constant_descriptor_tree *const c1
2877 = (const struct constant_descriptor_tree *) p1;
2878 const struct constant_descriptor_tree *const c2
2879 = (const struct constant_descriptor_tree *) p2;
2880 if (c1->hash != c2->hash)
2881 return 0;
2882 return compare_constant (c1->value, c2->value);
2885 /* Compare t1 and t2, and return 1 only if they are known to result in
2886 the same bit pattern on output. */
2888 static int
2889 compare_constant (const tree t1, const tree t2)
2891 enum tree_code typecode;
2893 if (t1 == NULL_TREE)
2894 return t2 == NULL_TREE;
2895 if (t2 == NULL_TREE)
2896 return 0;
2898 if (TREE_CODE (t1) != TREE_CODE (t2))
2899 return 0;
2901 switch (TREE_CODE (t1))
2903 case INTEGER_CST:
2904 /* Integer constants are the same only if the same width of type. */
2905 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2906 return 0;
2907 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2908 return 0;
2909 return tree_int_cst_equal (t1, t2);
2911 case REAL_CST:
2912 /* Real constants are the same only if the same width of type. */
2913 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2914 return 0;
2916 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
2918 case FIXED_CST:
2919 /* Fixed constants are the same only if the same width of type. */
2920 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2921 return 0;
2923 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
2925 case STRING_CST:
2926 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2927 return 0;
2929 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
2930 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
2931 TREE_STRING_LENGTH (t1)));
2933 case COMPLEX_CST:
2934 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
2935 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
2937 case VECTOR_CST:
2939 unsigned i;
2941 if (VECTOR_CST_NELTS (t1) != VECTOR_CST_NELTS (t2))
2942 return 0;
2944 for (i = 0; i < VECTOR_CST_NELTS (t1); ++i)
2945 if (!compare_constant (VECTOR_CST_ELT (t1, i),
2946 VECTOR_CST_ELT (t2, i)))
2947 return 0;
2949 return 1;
2952 case CONSTRUCTOR:
2954 vec<constructor_elt, va_gc> *v1, *v2;
2955 unsigned HOST_WIDE_INT idx;
2957 typecode = TREE_CODE (TREE_TYPE (t1));
2958 if (typecode != TREE_CODE (TREE_TYPE (t2)))
2959 return 0;
2961 if (typecode == ARRAY_TYPE)
2963 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
2964 /* For arrays, check that the sizes all match. */
2965 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
2966 || size_1 == -1
2967 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
2968 return 0;
2970 else
2972 /* For record and union constructors, require exact type
2973 equality. */
2974 if (TREE_TYPE (t1) != TREE_TYPE (t2))
2975 return 0;
2978 v1 = CONSTRUCTOR_ELTS (t1);
2979 v2 = CONSTRUCTOR_ELTS (t2);
2980 if (vec_safe_length (v1) != vec_safe_length (v2))
2981 return 0;
2983 for (idx = 0; idx < vec_safe_length (v1); ++idx)
2985 constructor_elt *c1 = &(*v1)[idx];
2986 constructor_elt *c2 = &(*v2)[idx];
2988 /* Check that each value is the same... */
2989 if (!compare_constant (c1->value, c2->value))
2990 return 0;
2991 /* ... and that they apply to the same fields! */
2992 if (typecode == ARRAY_TYPE)
2994 if (!compare_constant (c1->index, c2->index))
2995 return 0;
2997 else
2999 if (c1->index != c2->index)
3000 return 0;
3004 return 1;
3007 case ADDR_EXPR:
3008 case FDESC_EXPR:
3010 struct addr_const value1, value2;
3011 enum rtx_code code;
3012 int ret;
3014 decode_addr_const (t1, &value1);
3015 decode_addr_const (t2, &value2);
3017 if (value1.offset != value2.offset)
3018 return 0;
3020 code = GET_CODE (value1.base);
3021 if (code != GET_CODE (value2.base))
3022 return 0;
3024 switch (code)
3026 case SYMBOL_REF:
3027 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3028 break;
3030 case LABEL_REF:
3031 ret = (CODE_LABEL_NUMBER (XEXP (value1.base, 0))
3032 == CODE_LABEL_NUMBER (XEXP (value2.base, 0)));
3033 break;
3035 default:
3036 gcc_unreachable ();
3038 return ret;
3041 case PLUS_EXPR:
3042 case POINTER_PLUS_EXPR:
3043 case MINUS_EXPR:
3044 case RANGE_EXPR:
3045 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3046 && compare_constant(TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3048 CASE_CONVERT:
3049 case VIEW_CONVERT_EXPR:
3050 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3052 default:
3053 return 0;
3056 gcc_unreachable ();
3059 /* Make a copy of the whole tree structure for a constant. This
3060 handles the same types of nodes that compare_constant handles. */
3062 static tree
3063 copy_constant (tree exp)
3065 switch (TREE_CODE (exp))
3067 case ADDR_EXPR:
3068 /* For ADDR_EXPR, we do not want to copy the decl whose address
3069 is requested. We do want to copy constants though. */
3070 if (CONSTANT_CLASS_P (TREE_OPERAND (exp, 0)))
3071 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
3072 copy_constant (TREE_OPERAND (exp, 0)));
3073 else
3074 return copy_node (exp);
3076 case INTEGER_CST:
3077 case REAL_CST:
3078 case FIXED_CST:
3079 case STRING_CST:
3080 return copy_node (exp);
3082 case COMPLEX_CST:
3083 return build_complex (TREE_TYPE (exp),
3084 copy_constant (TREE_REALPART (exp)),
3085 copy_constant (TREE_IMAGPART (exp)));
3087 case PLUS_EXPR:
3088 case POINTER_PLUS_EXPR:
3089 case MINUS_EXPR:
3090 return build2 (TREE_CODE (exp), TREE_TYPE (exp),
3091 copy_constant (TREE_OPERAND (exp, 0)),
3092 copy_constant (TREE_OPERAND (exp, 1)));
3094 CASE_CONVERT:
3095 case VIEW_CONVERT_EXPR:
3096 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
3097 copy_constant (TREE_OPERAND (exp, 0)));
3099 case VECTOR_CST:
3100 return build_vector (TREE_TYPE (exp), VECTOR_CST_ELTS (exp));
3102 case CONSTRUCTOR:
3104 tree copy = copy_node (exp);
3105 vec<constructor_elt, va_gc> *v;
3106 unsigned HOST_WIDE_INT idx;
3107 tree purpose, value;
3109 vec_alloc (v, vec_safe_length (CONSTRUCTOR_ELTS (exp)));
3110 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (exp), idx, purpose, value)
3112 constructor_elt ce = {purpose, copy_constant (value)};
3113 v->quick_push (ce);
3115 CONSTRUCTOR_ELTS (copy) = v;
3116 return copy;
3119 default:
3120 gcc_unreachable ();
3124 /* Return the section into which constant EXP should be placed. */
3126 static section *
3127 get_constant_section (tree exp, unsigned int align)
3129 return targetm.asm_out.select_section (exp,
3130 compute_reloc_for_constant (exp),
3131 align);
3134 /* Return the size of constant EXP in bytes. */
3136 static HOST_WIDE_INT
3137 get_constant_size (tree exp)
3139 HOST_WIDE_INT size;
3141 size = int_size_in_bytes (TREE_TYPE (exp));
3142 if (TREE_CODE (exp) == STRING_CST)
3143 size = MAX (TREE_STRING_LENGTH (exp), size);
3144 return size;
3147 /* Subroutine of output_constant_def:
3148 No constant equal to EXP is known to have been output.
3149 Make a constant descriptor to enter EXP in the hash table.
3150 Assign the label number and construct RTL to refer to the
3151 constant's location in memory.
3152 Caller is responsible for updating the hash table. */
3154 static struct constant_descriptor_tree *
3155 build_constant_desc (tree exp)
3157 struct constant_descriptor_tree *desc;
3158 rtx symbol, rtl;
3159 char label[256];
3160 int labelno;
3161 tree decl;
3163 desc = ggc_alloc_constant_descriptor_tree ();
3164 desc->value = copy_constant (exp);
3166 /* Propagate marked-ness to copied constant. */
3167 if (flag_mudflap && mf_marked_p (exp))
3168 mf_mark (desc->value);
3170 /* Create a string containing the label name, in LABEL. */
3171 labelno = const_labelno++;
3172 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3174 /* Construct the VAR_DECL associated with the constant. */
3175 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3176 TREE_TYPE (exp));
3177 DECL_ARTIFICIAL (decl) = 1;
3178 DECL_IGNORED_P (decl) = 1;
3179 TREE_READONLY (decl) = 1;
3180 TREE_STATIC (decl) = 1;
3181 TREE_ADDRESSABLE (decl) = 1;
3182 /* We don't set the RTL yet as this would cause varpool to assume that the
3183 variable is referenced. Moreover, it would just be dropped in LTO mode.
3184 Instead we set the flag that will be recognized in make_decl_rtl. */
3185 DECL_IN_CONSTANT_POOL (decl) = 1;
3186 DECL_INITIAL (decl) = desc->value;
3187 /* ??? CONSTANT_ALIGNMENT hasn't been updated for vector types on most
3188 architectures so use DATA_ALIGNMENT as well, except for strings. */
3189 if (TREE_CODE (exp) == STRING_CST)
3191 #ifdef CONSTANT_ALIGNMENT
3192 DECL_ALIGN (decl) = CONSTANT_ALIGNMENT (exp, DECL_ALIGN (decl));
3193 #endif
3195 else
3196 align_variable (decl, 0);
3198 /* Now construct the SYMBOL_REF and the MEM. */
3199 if (use_object_blocks_p ())
3201 section *sect = get_constant_section (exp, DECL_ALIGN (decl));
3202 symbol = create_block_symbol (ggc_strdup (label),
3203 get_block_for_section (sect), -1);
3205 else
3206 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3207 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3208 SET_SYMBOL_REF_DECL (symbol, decl);
3209 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3211 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3212 set_mem_attributes (rtl, exp, 1);
3213 set_mem_alias_set (rtl, 0);
3214 set_mem_alias_set (rtl, const_alias_set);
3216 /* We cannot share RTX'es in pool entries.
3217 Mark this piece of RTL as required for unsharing. */
3218 RTX_FLAG (rtl, used) = 1;
3220 /* Set flags or add text to the name to record information, such as
3221 that it is a local symbol. If the name is changed, the macro
3222 ASM_OUTPUT_LABELREF will have to know how to strip this
3223 information. This call might invalidate our local variable
3224 SYMBOL; we can't use it afterward. */
3225 targetm.encode_section_info (exp, rtl, true);
3227 desc->rtl = rtl;
3229 return desc;
3232 /* Return an rtx representing a reference to constant data in memory
3233 for the constant expression EXP.
3235 If assembler code for such a constant has already been output,
3236 return an rtx to refer to it.
3237 Otherwise, output such a constant in memory
3238 and generate an rtx for it.
3240 If DEFER is nonzero, this constant can be deferred and output only
3241 if referenced in the function after all optimizations.
3243 `const_desc_table' records which constants already have label strings. */
3246 output_constant_def (tree exp, int defer)
3248 struct constant_descriptor_tree *desc;
3249 struct constant_descriptor_tree key;
3250 void **loc;
3252 /* Look up EXP in the table of constant descriptors. If we didn't find
3253 it, create a new one. */
3254 key.value = exp;
3255 key.hash = const_hash_1 (exp);
3256 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3258 desc = (struct constant_descriptor_tree *) *loc;
3259 if (desc == 0)
3261 desc = build_constant_desc (exp);
3262 desc->hash = key.hash;
3263 *loc = desc;
3266 maybe_output_constant_def_contents (desc, defer);
3267 return desc->rtl;
3270 /* Subroutine of output_constant_def: Decide whether or not we need to
3271 output the constant DESC now, and if so, do it. */
3272 static void
3273 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3274 int defer)
3276 rtx symbol = XEXP (desc->rtl, 0);
3277 tree exp = desc->value;
3279 if (flag_syntax_only)
3280 return;
3282 if (TREE_ASM_WRITTEN (exp))
3283 /* Already output; don't do it again. */
3284 return;
3286 /* We can always defer constants as long as the context allows
3287 doing so. */
3288 if (defer)
3290 /* Increment n_deferred_constants if it exists. It needs to be at
3291 least as large as the number of constants actually referred to
3292 by the function. If it's too small we'll stop looking too early
3293 and fail to emit constants; if it's too large we'll only look
3294 through the entire function when we could have stopped earlier. */
3295 if (cfun)
3296 n_deferred_constants++;
3297 return;
3300 output_constant_def_contents (symbol);
3303 /* Subroutine of output_constant_def_contents. Output the definition
3304 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3305 constant's alignment in bits. */
3307 static void
3308 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3310 HOST_WIDE_INT size;
3312 size = get_constant_size (exp);
3314 /* Do any machine/system dependent processing of the constant. */
3315 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3317 /* Output the value of EXP. */
3318 output_constant (exp, size, align);
3321 /* We must output the constant data referred to by SYMBOL; do so. */
3323 static void
3324 output_constant_def_contents (rtx symbol)
3326 tree decl = SYMBOL_REF_DECL (symbol);
3327 tree exp = DECL_INITIAL (decl);
3328 unsigned int align;
3329 bool asan_protected = false;
3331 /* Make sure any other constants whose addresses appear in EXP
3332 are assigned label numbers. */
3333 output_addressed_constants (exp);
3335 /* We are no longer deferring this constant. */
3336 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3338 if (flag_asan && TREE_CODE (exp) == STRING_CST
3339 && asan_protect_global (exp))
3341 asan_protected = true;
3342 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
3343 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
3346 /* If the constant is part of an object block, make sure that the
3347 decl has been positioned within its block, but do not write out
3348 its definition yet. output_object_blocks will do that later. */
3349 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3350 place_block_symbol (symbol);
3351 else
3353 align = DECL_ALIGN (decl);
3354 switch_to_section (get_constant_section (exp, align));
3355 if (align > BITS_PER_UNIT)
3356 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3357 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3358 if (asan_protected)
3360 HOST_WIDE_INT size = get_constant_size (exp);
3361 assemble_zeros (asan_red_zone_size (size));
3364 if (flag_mudflap)
3365 mudflap_enqueue_constant (exp);
3368 /* Look up EXP in the table of constant descriptors. Return the rtl
3369 if it has been emitted, else null. */
3372 lookup_constant_def (tree exp)
3374 struct constant_descriptor_tree *desc;
3375 struct constant_descriptor_tree key;
3377 key.value = exp;
3378 key.hash = const_hash_1 (exp);
3379 desc = (struct constant_descriptor_tree *)
3380 htab_find_with_hash (const_desc_htab, &key, key.hash);
3382 return (desc ? desc->rtl : NULL_RTX);
3385 /* Return a tree representing a reference to constant data in memory
3386 for the constant expression EXP.
3388 This is the counterpart of output_constant_def at the Tree level. */
3390 tree
3391 tree_output_constant_def (tree exp)
3393 struct constant_descriptor_tree *desc, key;
3394 void **loc;
3395 tree decl;
3397 /* Look up EXP in the table of constant descriptors. If we didn't find
3398 it, create a new one. */
3399 key.value = exp;
3400 key.hash = const_hash_1 (exp);
3401 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3403 desc = (struct constant_descriptor_tree *) *loc;
3404 if (desc == 0)
3406 desc = build_constant_desc (exp);
3407 desc->hash = key.hash;
3408 *loc = desc;
3411 decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3412 varpool_finalize_decl (decl);
3413 return decl;
3416 /* Used in the hash tables to avoid outputting the same constant
3417 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3418 are output once per function, not once per file. */
3419 /* ??? Only a few targets need per-function constant pools. Most
3420 can use one per-file pool. Should add a targetm bit to tell the
3421 difference. */
3423 struct GTY(()) rtx_constant_pool {
3424 /* Pointers to first and last constant in pool, as ordered by offset. */
3425 struct constant_descriptor_rtx *first;
3426 struct constant_descriptor_rtx *last;
3428 /* Hash facility for making memory-constants from constant rtl-expressions.
3429 It is used on RISC machines where immediate integer arguments and
3430 constant addresses are restricted so that such constants must be stored
3431 in memory. */
3432 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_htab;
3434 /* Current offset in constant pool (does not include any
3435 machine-specific header). */
3436 HOST_WIDE_INT offset;
3439 struct GTY((chain_next ("%h.next"))) constant_descriptor_rtx {
3440 struct constant_descriptor_rtx *next;
3441 rtx mem;
3442 rtx sym;
3443 rtx constant;
3444 HOST_WIDE_INT offset;
3445 hashval_t hash;
3446 enum machine_mode mode;
3447 unsigned int align;
3448 int labelno;
3449 int mark;
3452 /* Hash and compare functions for const_rtx_htab. */
3454 static hashval_t
3455 const_desc_rtx_hash (const void *ptr)
3457 const struct constant_descriptor_rtx *const desc
3458 = (const struct constant_descriptor_rtx *) ptr;
3459 return desc->hash;
3462 static int
3463 const_desc_rtx_eq (const void *a, const void *b)
3465 const struct constant_descriptor_rtx *const x
3466 = (const struct constant_descriptor_rtx *) a;
3467 const struct constant_descriptor_rtx *const y
3468 = (const struct constant_descriptor_rtx *) b;
3470 if (x->mode != y->mode)
3471 return 0;
3472 return rtx_equal_p (x->constant, y->constant);
3475 /* This is the worker function for const_rtx_hash, called via for_each_rtx. */
3477 static int
3478 const_rtx_hash_1 (rtx *xp, void *data)
3480 unsigned HOST_WIDE_INT hwi;
3481 enum machine_mode mode;
3482 enum rtx_code code;
3483 hashval_t h, *hp;
3484 rtx x;
3486 x = *xp;
3487 code = GET_CODE (x);
3488 mode = GET_MODE (x);
3489 h = (hashval_t) code * 1048573 + mode;
3491 switch (code)
3493 case CONST_INT:
3494 hwi = INTVAL (x);
3495 fold_hwi:
3497 int shift = sizeof (hashval_t) * CHAR_BIT;
3498 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3499 int i;
3501 h ^= (hashval_t) hwi;
3502 for (i = 1; i < n; ++i)
3504 hwi >>= shift;
3505 h ^= (hashval_t) hwi;
3508 break;
3510 case CONST_DOUBLE:
3511 if (mode == VOIDmode)
3513 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3514 goto fold_hwi;
3516 else
3517 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3518 break;
3520 case CONST_FIXED:
3521 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3522 break;
3524 case CONST_VECTOR:
3526 int i;
3527 for (i = XVECLEN (x, 0); i-- > 0; )
3528 h = h * 251 + const_rtx_hash_1 (&XVECEXP (x, 0, i), data);
3530 break;
3532 case SYMBOL_REF:
3533 h ^= htab_hash_string (XSTR (x, 0));
3534 break;
3536 case LABEL_REF:
3537 h = h * 251 + CODE_LABEL_NUMBER (XEXP (x, 0));
3538 break;
3540 case UNSPEC:
3541 case UNSPEC_VOLATILE:
3542 h = h * 251 + XINT (x, 1);
3543 break;
3545 default:
3546 break;
3549 hp = (hashval_t *) data;
3550 *hp = *hp * 509 + h;
3551 return 0;
3554 /* Compute a hash value for X, which should be a constant. */
3556 static hashval_t
3557 const_rtx_hash (rtx x)
3559 hashval_t h = 0;
3560 for_each_rtx (&x, const_rtx_hash_1, &h);
3561 return h;
3565 /* Create and return a new rtx constant pool. */
3567 static struct rtx_constant_pool *
3568 create_constant_pool (void)
3570 struct rtx_constant_pool *pool;
3572 pool = ggc_alloc_rtx_constant_pool ();
3573 pool->const_rtx_htab = htab_create_ggc (31, const_desc_rtx_hash,
3574 const_desc_rtx_eq, NULL);
3575 pool->first = NULL;
3576 pool->last = NULL;
3577 pool->offset = 0;
3578 return pool;
3581 /* Initialize constant pool hashing for a new function. */
3583 void
3584 init_varasm_status (void)
3586 crtl->varasm.pool = create_constant_pool ();
3587 crtl->varasm.deferred_constants = 0;
3590 /* Given a MINUS expression, simplify it if both sides
3591 include the same symbol. */
3594 simplify_subtraction (rtx x)
3596 rtx r = simplify_rtx (x);
3597 return r ? r : x;
3600 /* Given a constant rtx X, make (or find) a memory constant for its value
3601 and return a MEM rtx to refer to it in memory. */
3604 force_const_mem (enum machine_mode mode, rtx x)
3606 struct constant_descriptor_rtx *desc, tmp;
3607 struct rtx_constant_pool *pool;
3608 char label[256];
3609 rtx def, symbol;
3610 hashval_t hash;
3611 unsigned int align;
3612 void **slot;
3614 /* If we're not allowed to drop X into the constant pool, don't. */
3615 if (targetm.cannot_force_const_mem (mode, x))
3616 return NULL_RTX;
3618 /* Record that this function has used a constant pool entry. */
3619 crtl->uses_const_pool = 1;
3621 /* Decide which pool to use. */
3622 pool = (targetm.use_blocks_for_constant_p (mode, x)
3623 ? shared_constant_pool
3624 : crtl->varasm.pool);
3626 /* Lookup the value in the hashtable. */
3627 tmp.constant = x;
3628 tmp.mode = mode;
3629 hash = const_rtx_hash (x);
3630 slot = htab_find_slot_with_hash (pool->const_rtx_htab, &tmp, hash, INSERT);
3631 desc = (struct constant_descriptor_rtx *) *slot;
3633 /* If the constant was already present, return its memory. */
3634 if (desc)
3635 return copy_rtx (desc->mem);
3637 /* Otherwise, create a new descriptor. */
3638 desc = ggc_alloc_constant_descriptor_rtx ();
3639 *slot = desc;
3641 /* Align the location counter as required by EXP's data type. */
3642 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3643 #ifdef CONSTANT_ALIGNMENT
3645 tree type = lang_hooks.types.type_for_mode (mode, 0);
3646 if (type != NULL_TREE)
3647 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3649 #endif
3651 pool->offset += (align / BITS_PER_UNIT) - 1;
3652 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3654 desc->next = NULL;
3655 desc->constant = copy_rtx (tmp.constant);
3656 desc->offset = pool->offset;
3657 desc->hash = hash;
3658 desc->mode = mode;
3659 desc->align = align;
3660 desc->labelno = const_labelno;
3661 desc->mark = 0;
3663 pool->offset += GET_MODE_SIZE (mode);
3664 if (pool->last)
3665 pool->last->next = desc;
3666 else
3667 pool->first = pool->last = desc;
3668 pool->last = desc;
3670 /* Create a string containing the label name, in LABEL. */
3671 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3672 ++const_labelno;
3674 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3675 the constants pool. */
3676 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3678 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3679 symbol = create_block_symbol (ggc_strdup (label),
3680 get_block_for_section (sect), -1);
3682 else
3683 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3684 desc->sym = symbol;
3685 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3686 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3687 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3689 /* Construct the MEM. */
3690 desc->mem = def = gen_const_mem (mode, symbol);
3691 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3692 set_mem_align (def, align);
3694 /* If we're dropping a label to the constant pool, make sure we
3695 don't delete it. */
3696 if (GET_CODE (x) == LABEL_REF)
3697 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3699 return copy_rtx (def);
3702 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3705 get_pool_constant (rtx addr)
3707 return SYMBOL_REF_CONSTANT (addr)->constant;
3710 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3711 and whether it has been output or not. */
3714 get_pool_constant_mark (rtx addr, bool *pmarked)
3716 struct constant_descriptor_rtx *desc;
3718 desc = SYMBOL_REF_CONSTANT (addr);
3719 *pmarked = (desc->mark != 0);
3720 return desc->constant;
3723 /* Similar, return the mode. */
3725 enum machine_mode
3726 get_pool_mode (const_rtx addr)
3728 return SYMBOL_REF_CONSTANT (addr)->mode;
3731 /* Return the size of the constant pool. */
3734 get_pool_size (void)
3736 return crtl->varasm.pool->offset;
3739 /* Worker function for output_constant_pool_1. Emit assembly for X
3740 in MODE with known alignment ALIGN. */
3742 static void
3743 output_constant_pool_2 (enum machine_mode mode, rtx x, unsigned int align)
3745 switch (GET_MODE_CLASS (mode))
3747 case MODE_FLOAT:
3748 case MODE_DECIMAL_FLOAT:
3750 REAL_VALUE_TYPE r;
3752 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3753 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3754 assemble_real (r, mode, align);
3755 break;
3758 case MODE_INT:
3759 case MODE_PARTIAL_INT:
3760 case MODE_FRACT:
3761 case MODE_UFRACT:
3762 case MODE_ACCUM:
3763 case MODE_UACCUM:
3764 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3765 break;
3767 case MODE_VECTOR_FLOAT:
3768 case MODE_VECTOR_INT:
3769 case MODE_VECTOR_FRACT:
3770 case MODE_VECTOR_UFRACT:
3771 case MODE_VECTOR_ACCUM:
3772 case MODE_VECTOR_UACCUM:
3774 int i, units;
3775 enum machine_mode submode = GET_MODE_INNER (mode);
3776 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3778 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3779 units = CONST_VECTOR_NUNITS (x);
3781 for (i = 0; i < units; i++)
3783 rtx elt = CONST_VECTOR_ELT (x, i);
3784 output_constant_pool_2 (submode, elt, i ? subalign : align);
3787 break;
3789 default:
3790 gcc_unreachable ();
3794 /* Worker function for output_constant_pool. Emit constant DESC,
3795 giving it ALIGN bits of alignment. */
3797 static void
3798 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3799 unsigned int align)
3801 rtx x, tmp;
3803 x = desc->constant;
3805 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3806 whose CODE_LABEL has been deleted. This can occur if a jump table
3807 is eliminated by optimization. If so, write a constant of zero
3808 instead. Note that this can also happen by turning the
3809 CODE_LABEL into a NOTE. */
3810 /* ??? This seems completely and utterly wrong. Certainly it's
3811 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3812 functioning even with INSN_DELETED_P and friends. */
3814 tmp = x;
3815 switch (GET_CODE (tmp))
3817 case CONST:
3818 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3819 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
3820 break;
3821 tmp = XEXP (XEXP (tmp, 0), 0);
3822 /* FALLTHRU */
3824 case LABEL_REF:
3825 tmp = XEXP (tmp, 0);
3826 gcc_assert (!INSN_DELETED_P (tmp));
3827 gcc_assert (!NOTE_P (tmp)
3828 || NOTE_KIND (tmp) != NOTE_INSN_DELETED);
3829 break;
3831 default:
3832 break;
3835 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3836 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3837 align, desc->labelno, done);
3838 #endif
3840 assemble_align (align);
3842 /* Output the label. */
3843 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3845 /* Output the data. */
3846 output_constant_pool_2 (desc->mode, x, align);
3848 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3849 sections have proper size. */
3850 if (align > GET_MODE_BITSIZE (desc->mode)
3851 && in_section
3852 && (in_section->common.flags & SECTION_MERGE))
3853 assemble_align (align);
3855 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3856 done:
3857 #endif
3858 return;
3861 /* Given a SYMBOL_REF CURRENT_RTX, mark it and all constants it refers
3862 to as used. Emit referenced deferred strings. This function can
3863 be used with for_each_rtx to mark all SYMBOL_REFs in an rtx. */
3865 static int
3866 mark_constant (rtx *current_rtx, void *data ATTRIBUTE_UNUSED)
3868 rtx x = *current_rtx;
3870 if (x == NULL_RTX || GET_CODE (x) != SYMBOL_REF)
3871 return 0;
3873 if (CONSTANT_POOL_ADDRESS_P (x))
3875 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
3876 if (desc->mark == 0)
3878 desc->mark = 1;
3879 for_each_rtx (&desc->constant, mark_constant, NULL);
3882 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3884 tree decl = SYMBOL_REF_DECL (x);
3885 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
3887 n_deferred_constants--;
3888 output_constant_def_contents (x);
3892 return -1;
3895 /* Look through appropriate parts of INSN, marking all entries in the
3896 constant pool which are actually being used. Entries that are only
3897 referenced by other constants are also marked as used. Emit
3898 deferred strings that are used. */
3900 static void
3901 mark_constants (rtx insn)
3903 if (!INSN_P (insn))
3904 return;
3906 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3907 insns, not any notes that may be attached. We don't want to mark
3908 a constant just because it happens to appear in a REG_EQUIV note. */
3909 if (GET_CODE (PATTERN (insn)) == SEQUENCE)
3911 rtx seq = PATTERN (insn);
3912 int i, n = XVECLEN (seq, 0);
3913 for (i = 0; i < n; ++i)
3915 rtx subinsn = XVECEXP (seq, 0, i);
3916 if (INSN_P (subinsn))
3917 for_each_rtx (&PATTERN (subinsn), mark_constant, NULL);
3920 else
3921 for_each_rtx (&PATTERN (insn), mark_constant, NULL);
3924 /* Look through the instructions for this function, and mark all the
3925 entries in POOL which are actually being used. Emit deferred constants
3926 which have indeed been used. */
3928 static void
3929 mark_constant_pool (void)
3931 rtx insn;
3933 if (!crtl->uses_const_pool && n_deferred_constants == 0)
3934 return;
3936 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3937 mark_constants (insn);
3940 /* Write all the constants in POOL. */
3942 static void
3943 output_constant_pool_contents (struct rtx_constant_pool *pool)
3945 struct constant_descriptor_rtx *desc;
3947 for (desc = pool->first; desc ; desc = desc->next)
3948 if (desc->mark)
3950 /* If the constant is part of an object_block, make sure that
3951 the constant has been positioned within its block, but do not
3952 write out its definition yet. output_object_blocks will do
3953 that later. */
3954 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
3955 && SYMBOL_REF_BLOCK (desc->sym))
3956 place_block_symbol (desc->sym);
3957 else
3959 switch_to_section (targetm.asm_out.select_rtx_section
3960 (desc->mode, desc->constant, desc->align));
3961 output_constant_pool_1 (desc, desc->align);
3966 /* Mark all constants that are used in the current function, then write
3967 out the function's private constant pool. */
3969 static void
3970 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
3971 tree fndecl ATTRIBUTE_UNUSED)
3973 struct rtx_constant_pool *pool = crtl->varasm.pool;
3975 /* It is possible for gcc to call force_const_mem and then to later
3976 discard the instructions which refer to the constant. In such a
3977 case we do not need to output the constant. */
3978 mark_constant_pool ();
3980 #ifdef ASM_OUTPUT_POOL_PROLOGUE
3981 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
3982 #endif
3984 output_constant_pool_contents (pool);
3986 #ifdef ASM_OUTPUT_POOL_EPILOGUE
3987 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
3988 #endif
3991 /* Write the contents of the shared constant pool. */
3993 void
3994 output_shared_constant_pool (void)
3996 output_constant_pool_contents (shared_constant_pool);
3999 /* Determine what kind of relocations EXP may need. */
4002 compute_reloc_for_constant (tree exp)
4004 int reloc = 0, reloc2;
4005 tree tem;
4007 switch (TREE_CODE (exp))
4009 case ADDR_EXPR:
4010 case FDESC_EXPR:
4011 /* Go inside any operations that get_inner_reference can handle and see
4012 if what's inside is a constant: no need to do anything here for
4013 addresses of variables or functions. */
4014 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4015 tem = TREE_OPERAND (tem, 0))
4018 if (TREE_CODE (tem) == MEM_REF
4019 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4021 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4022 break;
4025 if (TREE_PUBLIC (tem))
4026 reloc |= 2;
4027 else
4028 reloc |= 1;
4029 break;
4031 case PLUS_EXPR:
4032 case POINTER_PLUS_EXPR:
4033 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4034 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4035 break;
4037 case MINUS_EXPR:
4038 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4039 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4040 /* The difference of two local labels is computable at link time. */
4041 if (reloc == 1 && reloc2 == 1)
4042 reloc = 0;
4043 else
4044 reloc |= reloc2;
4045 break;
4047 CASE_CONVERT:
4048 case VIEW_CONVERT_EXPR:
4049 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4050 break;
4052 case CONSTRUCTOR:
4054 unsigned HOST_WIDE_INT idx;
4055 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4056 if (tem != 0)
4057 reloc |= compute_reloc_for_constant (tem);
4059 break;
4061 default:
4062 break;
4064 return reloc;
4067 /* Find all the constants whose addresses are referenced inside of EXP,
4068 and make sure assembler code with a label has been output for each one.
4069 Indicate whether an ADDR_EXPR has been encountered. */
4071 static void
4072 output_addressed_constants (tree exp)
4074 tree tem;
4076 switch (TREE_CODE (exp))
4078 case ADDR_EXPR:
4079 case FDESC_EXPR:
4080 /* Go inside any operations that get_inner_reference can handle and see
4081 if what's inside is a constant: no need to do anything here for
4082 addresses of variables or functions. */
4083 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4084 tem = TREE_OPERAND (tem, 0))
4087 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4088 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4089 tem = DECL_INITIAL (tem);
4091 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4092 output_constant_def (tem, 0);
4094 if (TREE_CODE (tem) == MEM_REF)
4095 output_addressed_constants (TREE_OPERAND (tem, 0));
4096 break;
4098 case PLUS_EXPR:
4099 case POINTER_PLUS_EXPR:
4100 case MINUS_EXPR:
4101 output_addressed_constants (TREE_OPERAND (exp, 1));
4102 /* Fall through. */
4104 CASE_CONVERT:
4105 case VIEW_CONVERT_EXPR:
4106 output_addressed_constants (TREE_OPERAND (exp, 0));
4107 break;
4109 case CONSTRUCTOR:
4111 unsigned HOST_WIDE_INT idx;
4112 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4113 if (tem != 0)
4114 output_addressed_constants (tem);
4116 break;
4118 default:
4119 break;
4123 /* Whether a constructor CTOR is a valid static constant initializer if all
4124 its elements are. This used to be internal to initializer_constant_valid_p
4125 and has been exposed to let other functions like categorize_ctor_elements
4126 evaluate the property while walking a constructor for other purposes. */
4128 bool
4129 constructor_static_from_elts_p (const_tree ctor)
4131 return (TREE_CONSTANT (ctor)
4132 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4133 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4134 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4137 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4138 tree *cache);
4140 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4141 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4142 which are valid when ENDTYPE is an integer of any size; in
4143 particular, this does not accept a pointer minus a constant. This
4144 returns null_pointer_node if the VALUE is an absolute constant
4145 which can be used to initialize a static variable. Otherwise it
4146 returns NULL. */
4148 static tree
4149 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4151 tree op0, op1;
4153 if (!INTEGRAL_TYPE_P (endtype))
4154 return NULL_TREE;
4156 op0 = TREE_OPERAND (value, 0);
4157 op1 = TREE_OPERAND (value, 1);
4159 /* Like STRIP_NOPS except allow the operand mode to widen. This
4160 works around a feature of fold that simplifies (int)(p1 - p2) to
4161 ((int)p1 - (int)p2) under the theory that the narrower operation
4162 is cheaper. */
4164 while (CONVERT_EXPR_P (op0)
4165 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4167 tree inner = TREE_OPERAND (op0, 0);
4168 if (inner == error_mark_node
4169 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4170 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
4171 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4172 break;
4173 op0 = inner;
4176 while (CONVERT_EXPR_P (op1)
4177 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4179 tree inner = TREE_OPERAND (op1, 0);
4180 if (inner == error_mark_node
4181 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4182 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
4183 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4184 break;
4185 op1 = inner;
4188 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4189 if (!op0)
4190 return NULL_TREE;
4192 op1 = initializer_constant_valid_p_1 (op1, endtype,
4193 cache ? cache + 2 : NULL);
4194 /* Both initializers must be known. */
4195 if (op1)
4197 if (op0 == op1
4198 && (op0 == null_pointer_node
4199 || TREE_CODE (value) == MINUS_EXPR))
4200 return null_pointer_node;
4202 /* Support differences between labels. */
4203 if (TREE_CODE (op0) == LABEL_DECL
4204 && TREE_CODE (op1) == LABEL_DECL)
4205 return null_pointer_node;
4207 if (TREE_CODE (op0) == STRING_CST
4208 && TREE_CODE (op1) == STRING_CST
4209 && operand_equal_p (op0, op1, 1))
4210 return null_pointer_node;
4213 return NULL_TREE;
4216 /* Helper function of initializer_constant_valid_p.
4217 Return nonzero if VALUE is a valid constant-valued expression
4218 for use in initializing a static variable; one that can be an
4219 element of a "constant" initializer.
4221 Return null_pointer_node if the value is absolute;
4222 if it is relocatable, return the variable that determines the relocation.
4223 We assume that VALUE has been folded as much as possible;
4224 therefore, we do not need to check for such things as
4225 arithmetic-combinations of integers.
4227 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4229 static tree
4230 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4232 tree ret;
4234 switch (TREE_CODE (value))
4236 case CONSTRUCTOR:
4237 if (constructor_static_from_elts_p (value))
4239 unsigned HOST_WIDE_INT idx;
4240 tree elt;
4241 bool absolute = true;
4243 if (cache && cache[0] == value)
4244 return cache[1];
4245 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4247 tree reloc;
4248 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4249 NULL);
4250 if (!reloc)
4252 if (cache)
4254 cache[0] = value;
4255 cache[1] = NULL_TREE;
4257 return NULL_TREE;
4259 if (reloc != null_pointer_node)
4260 absolute = false;
4262 /* For a non-absolute relocation, there is no single
4263 variable that can be "the variable that determines the
4264 relocation." */
4265 if (cache)
4267 cache[0] = value;
4268 cache[1] = absolute ? null_pointer_node : error_mark_node;
4270 return absolute ? null_pointer_node : error_mark_node;
4273 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4275 case INTEGER_CST:
4276 case VECTOR_CST:
4277 case REAL_CST:
4278 case FIXED_CST:
4279 case STRING_CST:
4280 case COMPLEX_CST:
4281 return null_pointer_node;
4283 case ADDR_EXPR:
4284 case FDESC_EXPR:
4286 tree op0 = staticp (TREE_OPERAND (value, 0));
4287 if (op0)
4289 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4290 to be a constant, this is old-skool offsetof-like nonsense. */
4291 if (TREE_CODE (op0) == INDIRECT_REF
4292 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4293 return null_pointer_node;
4294 /* Taking the address of a nested function involves a trampoline,
4295 unless we don't need or want one. */
4296 if (TREE_CODE (op0) == FUNCTION_DECL
4297 && DECL_STATIC_CHAIN (op0)
4298 && !TREE_NO_TRAMPOLINE (value))
4299 return NULL_TREE;
4300 /* "&{...}" requires a temporary to hold the constructed
4301 object. */
4302 if (TREE_CODE (op0) == CONSTRUCTOR)
4303 return NULL_TREE;
4305 return op0;
4308 case NON_LVALUE_EXPR:
4309 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4310 endtype, cache);
4312 case VIEW_CONVERT_EXPR:
4314 tree src = TREE_OPERAND (value, 0);
4315 tree src_type = TREE_TYPE (src);
4316 tree dest_type = TREE_TYPE (value);
4318 /* Allow view-conversions from aggregate to non-aggregate type only
4319 if the bit pattern is fully preserved afterwards; otherwise, the
4320 RTL expander won't be able to apply a subsequent transformation
4321 to the underlying constructor. */
4322 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4324 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4325 return initializer_constant_valid_p_1 (src, endtype, cache);
4326 else
4327 return NULL_TREE;
4330 /* Allow all other kinds of view-conversion. */
4331 return initializer_constant_valid_p_1 (src, endtype, cache);
4334 CASE_CONVERT:
4336 tree src = TREE_OPERAND (value, 0);
4337 tree src_type = TREE_TYPE (src);
4338 tree dest_type = TREE_TYPE (value);
4340 /* Allow conversions between pointer types, floating-point
4341 types, and offset types. */
4342 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4343 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4344 || (TREE_CODE (dest_type) == OFFSET_TYPE
4345 && TREE_CODE (src_type) == OFFSET_TYPE))
4346 return initializer_constant_valid_p_1 (src, endtype, cache);
4348 /* Allow length-preserving conversions between integer types. */
4349 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4350 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4351 return initializer_constant_valid_p_1 (src, endtype, cache);
4353 /* Allow conversions between other integer types only if
4354 explicit value. */
4355 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type))
4357 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4358 if (inner == null_pointer_node)
4359 return null_pointer_node;
4360 break;
4363 /* Allow (int) &foo provided int is as wide as a pointer. */
4364 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4365 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4366 return initializer_constant_valid_p_1 (src, endtype, cache);
4368 /* Likewise conversions from int to pointers, but also allow
4369 conversions from 0. */
4370 if ((POINTER_TYPE_P (dest_type)
4371 || TREE_CODE (dest_type) == OFFSET_TYPE)
4372 && INTEGRAL_TYPE_P (src_type))
4374 if (TREE_CODE (src) == INTEGER_CST
4375 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4376 return null_pointer_node;
4377 if (integer_zerop (src))
4378 return null_pointer_node;
4379 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4380 return initializer_constant_valid_p_1 (src, endtype, cache);
4383 /* Allow conversions to struct or union types if the value
4384 inside is okay. */
4385 if (TREE_CODE (dest_type) == RECORD_TYPE
4386 || TREE_CODE (dest_type) == UNION_TYPE)
4387 return initializer_constant_valid_p_1 (src, endtype, cache);
4389 break;
4391 case POINTER_PLUS_EXPR:
4392 case PLUS_EXPR:
4393 /* Any valid floating-point constants will have been folded by now;
4394 with -frounding-math we hit this with addition of two constants. */
4395 if (TREE_CODE (endtype) == REAL_TYPE)
4396 return NULL_TREE;
4397 if (cache && cache[0] == value)
4398 return cache[1];
4399 if (! INTEGRAL_TYPE_P (endtype)
4400 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4402 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4403 tree valid0
4404 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4405 endtype, ncache);
4406 tree valid1
4407 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4408 endtype, ncache + 2);
4409 /* If either term is absolute, use the other term's relocation. */
4410 if (valid0 == null_pointer_node)
4411 ret = valid1;
4412 else if (valid1 == null_pointer_node)
4413 ret = valid0;
4414 /* Support narrowing pointer differences. */
4415 else
4416 ret = narrowing_initializer_constant_valid_p (value, endtype,
4417 ncache);
4419 else
4420 /* Support narrowing pointer differences. */
4421 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4422 if (cache)
4424 cache[0] = value;
4425 cache[1] = ret;
4427 return ret;
4429 case MINUS_EXPR:
4430 if (TREE_CODE (endtype) == REAL_TYPE)
4431 return NULL_TREE;
4432 if (cache && cache[0] == value)
4433 return cache[1];
4434 if (! INTEGRAL_TYPE_P (endtype)
4435 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4437 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4438 tree valid0
4439 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4440 endtype, ncache);
4441 tree valid1
4442 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4443 endtype, ncache + 2);
4444 /* Win if second argument is absolute. */
4445 if (valid1 == null_pointer_node)
4446 ret = valid0;
4447 /* Win if both arguments have the same relocation.
4448 Then the value is absolute. */
4449 else if (valid0 == valid1 && valid0 != 0)
4450 ret = null_pointer_node;
4451 /* Since GCC guarantees that string constants are unique in the
4452 generated code, a subtraction between two copies of the same
4453 constant string is absolute. */
4454 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4455 && valid1 && TREE_CODE (valid1) == STRING_CST
4456 && operand_equal_p (valid0, valid1, 1))
4457 ret = null_pointer_node;
4458 /* Support narrowing differences. */
4459 else
4460 ret = narrowing_initializer_constant_valid_p (value, endtype,
4461 ncache);
4463 else
4464 /* Support narrowing differences. */
4465 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4466 if (cache)
4468 cache[0] = value;
4469 cache[1] = ret;
4471 return ret;
4473 default:
4474 break;
4477 return NULL_TREE;
4480 /* Return nonzero if VALUE is a valid constant-valued expression
4481 for use in initializing a static variable; one that can be an
4482 element of a "constant" initializer.
4484 Return null_pointer_node if the value is absolute;
4485 if it is relocatable, return the variable that determines the relocation.
4486 We assume that VALUE has been folded as much as possible;
4487 therefore, we do not need to check for such things as
4488 arithmetic-combinations of integers. */
4489 tree
4490 initializer_constant_valid_p (tree value, tree endtype)
4492 return initializer_constant_valid_p_1 (value, endtype, NULL);
4495 /* Return true if VALUE is a valid constant-valued expression
4496 for use in initializing a static bit-field; one that can be
4497 an element of a "constant" initializer. */
4499 bool
4500 initializer_constant_valid_for_bitfield_p (tree value)
4502 /* For bitfields we support integer constants or possibly nested aggregates
4503 of such. */
4504 switch (TREE_CODE (value))
4506 case CONSTRUCTOR:
4508 unsigned HOST_WIDE_INT idx;
4509 tree elt;
4511 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4512 if (!initializer_constant_valid_for_bitfield_p (elt))
4513 return false;
4514 return true;
4517 case INTEGER_CST:
4518 case REAL_CST:
4519 return true;
4521 case VIEW_CONVERT_EXPR:
4522 case NON_LVALUE_EXPR:
4523 return
4524 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4526 default:
4527 break;
4530 return false;
4533 /* output_constructor outer state of relevance in recursive calls, typically
4534 for nested aggregate bitfields. */
4536 typedef struct {
4537 unsigned int bit_offset; /* current position in ... */
4538 int byte; /* ... the outer byte buffer. */
4539 } oc_outer_state;
4541 static unsigned HOST_WIDE_INT
4542 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int,
4543 oc_outer_state *);
4545 /* Output assembler code for constant EXP, with no label.
4546 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4547 Assumes output_addressed_constants has been done on EXP already.
4549 Generate exactly SIZE bytes of assembler data, padding at the end
4550 with zeros if necessary. SIZE must always be specified.
4552 SIZE is important for structure constructors,
4553 since trailing members may have been omitted from the constructor.
4554 It is also important for initialization of arrays from string constants
4555 since the full length of the string constant might not be wanted.
4556 It is also needed for initialization of unions, where the initializer's
4557 type is just one member, and that may not be as long as the union.
4559 There a case in which we would fail to output exactly SIZE bytes:
4560 for a structure constructor that wants to produce more than SIZE bytes.
4561 But such constructors will never be generated for any possible input.
4563 ALIGN is the alignment of the data in bits. */
4565 void
4566 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align)
4568 enum tree_code code;
4569 unsigned HOST_WIDE_INT thissize;
4571 if (size == 0 || flag_syntax_only)
4572 return;
4574 /* See if we're trying to initialize a pointer in a non-default mode
4575 to the address of some declaration somewhere. If the target says
4576 the mode is valid for pointers, assume the target has a way of
4577 resolving it. */
4578 if (TREE_CODE (exp) == NOP_EXPR
4579 && POINTER_TYPE_P (TREE_TYPE (exp))
4580 && targetm.addr_space.valid_pointer_mode
4581 (TYPE_MODE (TREE_TYPE (exp)),
4582 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4584 tree saved_type = TREE_TYPE (exp);
4586 /* Peel off any intermediate conversions-to-pointer for valid
4587 pointer modes. */
4588 while (TREE_CODE (exp) == NOP_EXPR
4589 && POINTER_TYPE_P (TREE_TYPE (exp))
4590 && targetm.addr_space.valid_pointer_mode
4591 (TYPE_MODE (TREE_TYPE (exp)),
4592 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4593 exp = TREE_OPERAND (exp, 0);
4595 /* If what we're left with is the address of something, we can
4596 convert the address to the final type and output it that
4597 way. */
4598 if (TREE_CODE (exp) == ADDR_EXPR)
4599 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4600 /* Likewise for constant ints. */
4601 else if (TREE_CODE (exp) == INTEGER_CST)
4602 exp = build_int_cst_wide (saved_type, TREE_INT_CST_LOW (exp),
4603 TREE_INT_CST_HIGH (exp));
4607 /* Eliminate any conversions since we'll be outputting the underlying
4608 constant. */
4609 while (CONVERT_EXPR_P (exp)
4610 || TREE_CODE (exp) == NON_LVALUE_EXPR
4611 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4613 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4614 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4616 /* Make sure eliminating the conversion is really a no-op, except with
4617 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4618 union types to allow for Ada unchecked unions. */
4619 if (type_size > op_size
4620 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4621 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4622 /* Keep the conversion. */
4623 break;
4624 else
4625 exp = TREE_OPERAND (exp, 0);
4628 code = TREE_CODE (TREE_TYPE (exp));
4629 thissize = int_size_in_bytes (TREE_TYPE (exp));
4631 /* Allow a constructor with no elements for any data type.
4632 This means to fill the space with zeros. */
4633 if (TREE_CODE (exp) == CONSTRUCTOR
4634 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4636 assemble_zeros (size);
4637 return;
4640 if (TREE_CODE (exp) == FDESC_EXPR)
4642 #ifdef ASM_OUTPUT_FDESC
4643 HOST_WIDE_INT part = tree_low_cst (TREE_OPERAND (exp, 1), 0);
4644 tree decl = TREE_OPERAND (exp, 0);
4645 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4646 #else
4647 gcc_unreachable ();
4648 #endif
4649 return;
4652 /* Now output the underlying data. If we've handling the padding, return.
4653 Otherwise, break and ensure SIZE is the size written. */
4654 switch (code)
4656 case BOOLEAN_TYPE:
4657 case INTEGER_TYPE:
4658 case ENUMERAL_TYPE:
4659 case POINTER_TYPE:
4660 case REFERENCE_TYPE:
4661 case OFFSET_TYPE:
4662 case FIXED_POINT_TYPE:
4663 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
4664 EXPAND_INITIALIZER),
4665 MIN (size, thissize), align, 0))
4666 error ("initializer for integer/fixed-point value is too complicated");
4667 break;
4669 case REAL_TYPE:
4670 if (TREE_CODE (exp) != REAL_CST)
4671 error ("initializer for floating value is not a floating constant");
4672 else
4673 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)), align);
4674 break;
4676 case COMPLEX_TYPE:
4677 output_constant (TREE_REALPART (exp), thissize / 2, align);
4678 output_constant (TREE_IMAGPART (exp), thissize / 2,
4679 min_align (align, BITS_PER_UNIT * (thissize / 2)));
4680 break;
4682 case ARRAY_TYPE:
4683 case VECTOR_TYPE:
4684 switch (TREE_CODE (exp))
4686 case CONSTRUCTOR:
4687 output_constructor (exp, size, align, NULL);
4688 return;
4689 case STRING_CST:
4690 thissize
4691 = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4692 assemble_string (TREE_STRING_POINTER (exp), thissize);
4693 break;
4694 case VECTOR_CST:
4696 enum machine_mode inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4697 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4698 int elt_size = GET_MODE_SIZE (inner);
4699 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align);
4700 thissize = elt_size;
4701 for (unsigned int i = 1; i < VECTOR_CST_NELTS (exp); i++)
4703 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign);
4704 thissize += elt_size;
4706 break;
4708 default:
4709 gcc_unreachable ();
4711 break;
4713 case RECORD_TYPE:
4714 case UNION_TYPE:
4715 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4716 output_constructor (exp, size, align, NULL);
4717 return;
4719 case ERROR_MARK:
4720 return;
4722 default:
4723 gcc_unreachable ();
4726 if (size > thissize)
4727 assemble_zeros (size - thissize);
4731 /* Subroutine of output_constructor, used for computing the size of
4732 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4733 type with an unspecified upper bound. */
4735 static unsigned HOST_WIDE_INT
4736 array_size_for_constructor (tree val)
4738 tree max_index;
4739 unsigned HOST_WIDE_INT cnt;
4740 tree index, value, tmp;
4741 double_int i;
4743 /* This code used to attempt to handle string constants that are not
4744 arrays of single-bytes, but nothing else does, so there's no point in
4745 doing it here. */
4746 if (TREE_CODE (val) == STRING_CST)
4747 return TREE_STRING_LENGTH (val);
4749 max_index = NULL_TREE;
4750 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
4752 if (TREE_CODE (index) == RANGE_EXPR)
4753 index = TREE_OPERAND (index, 1);
4754 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
4755 max_index = index;
4758 if (max_index == NULL_TREE)
4759 return 0;
4761 /* Compute the total number of array elements. */
4762 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
4763 i = tree_to_double_int (max_index) - tree_to_double_int (tmp);
4764 i += double_int_one;
4766 /* Multiply by the array element unit size to find number of bytes. */
4767 i *= tree_to_double_int (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
4769 gcc_assert (i.fits_uhwi ());
4770 return i.low;
4773 /* Other datastructures + helpers for output_constructor. */
4775 /* output_constructor local state to support interaction with helpers. */
4777 typedef struct {
4779 /* Received arguments. */
4780 tree exp; /* Constructor expression. */
4781 tree type; /* Type of constructor expression. */
4782 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */
4783 unsigned int align; /* Known initial alignment. */
4784 tree min_index; /* Lower bound if specified for an array. */
4786 /* Output processing state. */
4787 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */
4788 int byte; /* Part of a bitfield byte yet to be output. */
4789 int last_relative_index; /* Implicit or explicit index of the last
4790 array element output within a bitfield. */
4791 bool byte_buffer_in_use; /* Whether BYTE is in use. */
4793 /* Current element. */
4794 tree field; /* Current field decl in a record. */
4795 tree val; /* Current element value. */
4796 tree index; /* Current element index. */
4798 } oc_local_state;
4800 /* Helper for output_constructor. From the current LOCAL state, output a
4801 RANGE_EXPR element. */
4803 static void
4804 output_constructor_array_range (oc_local_state *local)
4806 unsigned HOST_WIDE_INT fieldsize
4807 = int_size_in_bytes (TREE_TYPE (local->type));
4809 HOST_WIDE_INT lo_index
4810 = tree_low_cst (TREE_OPERAND (local->index, 0), 0);
4811 HOST_WIDE_INT hi_index
4812 = tree_low_cst (TREE_OPERAND (local->index, 1), 0);
4813 HOST_WIDE_INT index;
4815 unsigned int align2
4816 = min_align (local->align, fieldsize * BITS_PER_UNIT);
4818 for (index = lo_index; index <= hi_index; index++)
4820 /* Output the element's initial value. */
4821 if (local->val == NULL_TREE)
4822 assemble_zeros (fieldsize);
4823 else
4824 output_constant (local->val, fieldsize, align2);
4826 /* Count its size. */
4827 local->total_bytes += fieldsize;
4831 /* Helper for output_constructor. From the current LOCAL state, output a
4832 field element that is not true bitfield or part of an outer one. */
4834 static void
4835 output_constructor_regular_field (oc_local_state *local)
4837 /* Field size and position. Since this structure is static, we know the
4838 positions are constant. */
4839 unsigned HOST_WIDE_INT fieldsize;
4840 HOST_WIDE_INT fieldpos;
4842 unsigned int align2;
4844 if (local->index != NULL_TREE)
4846 /* Perform the index calculation in modulo arithmetic but
4847 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
4848 but we are using an unsigned sizetype. */
4849 unsigned prec = TYPE_PRECISION (sizetype);
4850 double_int idx = tree_to_double_int (local->index)
4851 - tree_to_double_int (local->min_index);
4852 idx = idx.sext (prec);
4853 fieldpos = (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (local->val)), 1)
4854 * idx.low);
4856 else if (local->field != NULL_TREE)
4857 fieldpos = int_byte_position (local->field);
4858 else
4859 fieldpos = 0;
4861 /* Output any buffered-up bit-fields preceding this element. */
4862 if (local->byte_buffer_in_use)
4864 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4865 local->total_bytes++;
4866 local->byte_buffer_in_use = false;
4869 /* Advance to offset of this element.
4870 Note no alignment needed in an array, since that is guaranteed
4871 if each element has the proper size. */
4872 if ((local->field != NULL_TREE || local->index != NULL_TREE)
4873 && fieldpos != local->total_bytes)
4875 gcc_assert (fieldpos >= local->total_bytes);
4876 assemble_zeros (fieldpos - local->total_bytes);
4877 local->total_bytes = fieldpos;
4880 /* Find the alignment of this element. */
4881 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
4883 /* Determine size this element should occupy. */
4884 if (local->field)
4886 fieldsize = 0;
4888 /* If this is an array with an unspecified upper bound,
4889 the initializer determines the size. */
4890 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
4891 but we cannot do this until the deprecated support for
4892 initializing zero-length array members is removed. */
4893 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
4894 && TYPE_DOMAIN (TREE_TYPE (local->field))
4895 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field))))
4897 fieldsize = array_size_for_constructor (local->val);
4898 /* Given a non-empty initialization, this field had
4899 better be last. */
4900 gcc_assert (!fieldsize || !DECL_CHAIN (local->field));
4902 else
4903 fieldsize = tree_low_cst (DECL_SIZE_UNIT (local->field), 1);
4905 else
4906 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
4908 /* Output the element's initial value. */
4909 if (local->val == NULL_TREE)
4910 assemble_zeros (fieldsize);
4911 else
4912 output_constant (local->val, fieldsize, align2);
4914 /* Count its size. */
4915 local->total_bytes += fieldsize;
4918 /* Helper for output_constructor. From the LOCAL state, output an element
4919 that is a true bitfield or part of an outer one. BIT_OFFSET is the offset
4920 from the start of a possibly ongoing outer byte buffer. */
4922 static void
4923 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
4925 /* Bit size of this element. */
4926 HOST_WIDE_INT ebitsize
4927 = (local->field
4928 ? tree_low_cst (DECL_SIZE (local->field), 1)
4929 : tree_low_cst (TYPE_SIZE (TREE_TYPE (local->type)), 1));
4931 /* Relative index of this element if this is an array component. */
4932 HOST_WIDE_INT relative_index
4933 = (!local->field
4934 ? (local->index
4935 ? (tree_low_cst (local->index, 0)
4936 - tree_low_cst (local->min_index, 0))
4937 : local->last_relative_index + 1)
4938 : 0);
4940 /* Bit position of this element from the start of the containing
4941 constructor. */
4942 HOST_WIDE_INT constructor_relative_ebitpos
4943 = (local->field
4944 ? int_bit_position (local->field)
4945 : ebitsize * relative_index);
4947 /* Bit position of this element from the start of a possibly ongoing
4948 outer byte buffer. */
4949 HOST_WIDE_INT byte_relative_ebitpos
4950 = bit_offset + constructor_relative_ebitpos;
4952 /* From the start of a possibly ongoing outer byte buffer, offsets to
4953 the first bit of this element and to the first bit past the end of
4954 this element. */
4955 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
4956 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
4958 local->last_relative_index = relative_index;
4960 if (local->val == NULL_TREE)
4961 local->val = integer_zero_node;
4963 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
4964 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
4965 local->val = TREE_OPERAND (local->val, 0);
4967 if (TREE_CODE (local->val) != INTEGER_CST
4968 && TREE_CODE (local->val) != CONSTRUCTOR)
4970 error ("invalid initial value for member %qE", DECL_NAME (local->field));
4971 return;
4974 /* If this field does not start in this (or next) byte, skip some bytes. */
4975 if (next_offset / BITS_PER_UNIT != local->total_bytes)
4977 /* Output remnant of any bit field in previous bytes. */
4978 if (local->byte_buffer_in_use)
4980 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4981 local->total_bytes++;
4982 local->byte_buffer_in_use = false;
4985 /* If still not at proper byte, advance to there. */
4986 if (next_offset / BITS_PER_UNIT != local->total_bytes)
4988 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
4989 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
4990 local->total_bytes = next_offset / BITS_PER_UNIT;
4994 /* Set up the buffer if necessary. */
4995 if (!local->byte_buffer_in_use)
4997 local->byte = 0;
4998 if (ebitsize > 0)
4999 local->byte_buffer_in_use = true;
5002 /* If this is nested constructor, recurse passing the bit offset and the
5003 pending data, then retrieve the new pending data afterwards. */
5004 if (TREE_CODE (local->val) == CONSTRUCTOR)
5006 oc_outer_state temp_state;
5007 temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5008 temp_state.byte = local->byte;
5009 local->total_bytes
5010 += output_constructor (local->val, 0, 0, &temp_state);
5011 local->byte = temp_state.byte;
5012 return;
5015 /* Otherwise, we must split the element into pieces that fall within
5016 separate bytes, and combine each byte with previous or following
5017 bit-fields. */
5018 while (next_offset < end_offset)
5020 int this_time;
5021 int shift;
5022 HOST_WIDE_INT value;
5023 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5024 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5026 /* Advance from byte to byte within this element when necessary. */
5027 while (next_byte != local->total_bytes)
5029 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5030 local->total_bytes++;
5031 local->byte = 0;
5034 /* Number of bits we can process at once (all part of the same byte). */
5035 this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5036 if (BYTES_BIG_ENDIAN)
5038 /* On big-endian machine, take the most significant bits
5039 first (of the bits that are significant)
5040 and put them into bytes from the most significant end. */
5041 shift = end_offset - next_offset - this_time;
5043 /* Don't try to take a bunch of bits that cross
5044 the word boundary in the INTEGER_CST. We can
5045 only select bits from the LOW or HIGH part
5046 not from both. */
5047 if (shift < HOST_BITS_PER_WIDE_INT
5048 && shift + this_time > HOST_BITS_PER_WIDE_INT)
5050 this_time = shift + this_time - HOST_BITS_PER_WIDE_INT;
5051 shift = HOST_BITS_PER_WIDE_INT;
5054 /* Now get the bits from the appropriate constant word. */
5055 if (shift < HOST_BITS_PER_WIDE_INT)
5056 value = TREE_INT_CST_LOW (local->val);
5057 else
5059 gcc_assert (shift < HOST_BITS_PER_DOUBLE_INT);
5060 value = TREE_INT_CST_HIGH (local->val);
5061 shift -= HOST_BITS_PER_WIDE_INT;
5064 /* Get the result. This works only when:
5065 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5066 local->byte |= (((value >> shift)
5067 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5068 << (BITS_PER_UNIT - this_time - next_bit));
5070 else
5072 /* On little-endian machines,
5073 take first the least significant bits of the value
5074 and pack them starting at the least significant
5075 bits of the bytes. */
5076 shift = next_offset - byte_relative_ebitpos;
5078 /* Don't try to take a bunch of bits that cross
5079 the word boundary in the INTEGER_CST. We can
5080 only select bits from the LOW or HIGH part
5081 not from both. */
5082 if (shift < HOST_BITS_PER_WIDE_INT
5083 && shift + this_time > HOST_BITS_PER_WIDE_INT)
5084 this_time = (HOST_BITS_PER_WIDE_INT - shift);
5086 /* Now get the bits from the appropriate constant word. */
5087 if (shift < HOST_BITS_PER_WIDE_INT)
5088 value = TREE_INT_CST_LOW (local->val);
5089 else
5091 gcc_assert (shift < HOST_BITS_PER_DOUBLE_INT);
5092 value = TREE_INT_CST_HIGH (local->val);
5093 shift -= HOST_BITS_PER_WIDE_INT;
5096 /* Get the result. This works only when:
5097 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5098 local->byte |= (((value >> shift)
5099 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5100 << next_bit);
5103 next_offset += this_time;
5104 local->byte_buffer_in_use = true;
5108 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5109 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5110 caller output state of relevance in recursive invocations. */
5112 static unsigned HOST_WIDE_INT
5113 output_constructor (tree exp, unsigned HOST_WIDE_INT size,
5114 unsigned int align, oc_outer_state *outer)
5116 unsigned HOST_WIDE_INT cnt;
5117 constructor_elt *ce;
5119 oc_local_state local;
5121 /* Setup our local state to communicate with helpers. */
5122 local.exp = exp;
5123 local.type = TREE_TYPE (exp);
5124 local.size = size;
5125 local.align = align;
5126 if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5127 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5128 else
5129 local.min_index = NULL_TREE;
5131 local.total_bytes = 0;
5132 local.byte_buffer_in_use = outer != NULL;
5133 local.byte = outer ? outer->byte : 0;
5134 local.last_relative_index = -1;
5136 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5138 /* As CE goes through the elements of the constant, FIELD goes through the
5139 structure fields if the constant is a structure. If the constant is a
5140 union, we override this by getting the field from the TREE_LIST element.
5141 But the constant could also be an array. Then FIELD is zero.
5143 There is always a maximum of one element in the chain LINK for unions
5144 (even if the initializer in a source program incorrectly contains
5145 more one). */
5147 if (TREE_CODE (local.type) == RECORD_TYPE)
5148 local.field = TYPE_FIELDS (local.type);
5149 else
5150 local.field = NULL_TREE;
5152 for (cnt = 0;
5153 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5154 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5156 local.val = ce->value;
5157 local.index = NULL_TREE;
5159 /* The element in a union constructor specifies the proper field
5160 or index. */
5161 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5162 local.field = ce->index;
5164 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5165 local.index = ce->index;
5167 if (local.field && flag_verbose_asm)
5168 fprintf (asm_out_file, "%s %s:\n",
5169 ASM_COMMENT_START,
5170 DECL_NAME (local.field)
5171 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5172 : "<anonymous>");
5174 /* Eliminate the marker that makes a cast not be an lvalue. */
5175 if (local.val != NULL_TREE)
5176 STRIP_NOPS (local.val);
5178 /* Output the current element, using the appropriate helper ... */
5180 /* For an array slice not part of an outer bitfield. */
5181 if (!outer
5182 && local.index != NULL_TREE
5183 && TREE_CODE (local.index) == RANGE_EXPR)
5184 output_constructor_array_range (&local);
5186 /* For a field that is neither a true bitfield nor part of an outer one,
5187 known to be at least byte aligned and multiple-of-bytes long. */
5188 else if (!outer
5189 && (local.field == NULL_TREE
5190 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5191 output_constructor_regular_field (&local);
5193 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5194 supported for scalar fields, so we may need to convert first. */
5195 else
5197 if (TREE_CODE (local.val) == REAL_CST)
5198 local.val
5199 = fold_unary (VIEW_CONVERT_EXPR,
5200 build_nonstandard_integer_type
5201 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5202 local.val);
5203 output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5207 /* If we are not at toplevel, save the pending data for our caller.
5208 Otherwise output the pending data and padding zeros as needed. */
5209 if (outer)
5210 outer->byte = local.byte;
5211 else
5213 if (local.byte_buffer_in_use)
5215 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5216 local.total_bytes++;
5219 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5221 assemble_zeros (local.size - local.total_bytes);
5222 local.total_bytes = local.size;
5226 return local.total_bytes;
5229 /* Mark DECL as weak. */
5231 static void
5232 mark_weak (tree decl)
5234 DECL_WEAK (decl) = 1;
5236 if (DECL_RTL_SET_P (decl)
5237 && MEM_P (DECL_RTL (decl))
5238 && XEXP (DECL_RTL (decl), 0)
5239 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5240 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5243 /* Merge weak status between NEWDECL and OLDDECL. */
5245 void
5246 merge_weak (tree newdecl, tree olddecl)
5248 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5250 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5252 tree *pwd;
5253 /* We put the NEWDECL on the weak_decls list at some point
5254 and OLDDECL as well. Keep just OLDDECL on the list. */
5255 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5256 if (TREE_VALUE (*pwd) == newdecl)
5258 *pwd = TREE_CHAIN (*pwd);
5259 break;
5262 return;
5265 if (DECL_WEAK (newdecl))
5267 tree wd;
5269 /* NEWDECL is weak, but OLDDECL is not. */
5271 /* If we already output the OLDDECL, we're in trouble; we can't
5272 go back and make it weak. This should never happen in
5273 unit-at-a-time compilation. */
5274 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5276 /* If we've already generated rtl referencing OLDDECL, we may
5277 have done so in a way that will not function properly with
5278 a weak symbol. Again in unit-at-a-time this should be
5279 impossible. */
5280 gcc_assert (!TREE_USED (olddecl)
5281 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5283 if (TARGET_SUPPORTS_WEAK)
5285 /* We put the NEWDECL on the weak_decls list at some point.
5286 Replace it with the OLDDECL. */
5287 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5288 if (TREE_VALUE (wd) == newdecl)
5290 TREE_VALUE (wd) = olddecl;
5291 break;
5293 /* We may not find the entry on the list. If NEWDECL is a
5294 weak alias, then we will have already called
5295 globalize_decl to remove the entry; in that case, we do
5296 not need to do anything. */
5299 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5300 mark_weak (olddecl);
5302 else
5303 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5304 weak. Just update NEWDECL to indicate that it's weak too. */
5305 mark_weak (newdecl);
5308 /* Declare DECL to be a weak symbol. */
5310 void
5311 declare_weak (tree decl)
5313 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5314 if (! TREE_PUBLIC (decl))
5315 error ("weak declaration of %q+D must be public", decl);
5316 else if (!TARGET_SUPPORTS_WEAK)
5317 warning (0, "weak declaration of %q+D not supported", decl);
5319 mark_weak (decl);
5320 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5321 DECL_ATTRIBUTES (decl)
5322 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5325 static void
5326 weak_finish_1 (tree decl)
5328 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5329 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5330 #endif
5332 if (! TREE_USED (decl))
5333 return;
5335 #ifdef ASM_WEAKEN_DECL
5336 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5337 #else
5338 #ifdef ASM_WEAKEN_LABEL
5339 ASM_WEAKEN_LABEL (asm_out_file, name);
5340 #else
5341 #ifdef ASM_OUTPUT_WEAK_ALIAS
5343 static bool warn_once = 0;
5344 if (! warn_once)
5346 warning (0, "only weak aliases are supported in this configuration");
5347 warn_once = 1;
5349 return;
5351 #endif
5352 #endif
5353 #endif
5356 /* Fiven an assembly name, find the decl it is associated with. */
5357 static tree
5358 find_decl (tree target)
5360 symtab_node node = symtab_node_for_asm (target);
5361 if (node)
5362 return node->symbol.decl;
5363 return NULL_TREE;
5366 /* This TREE_LIST contains weakref targets. */
5368 static GTY(()) tree weakref_targets;
5370 /* Emit any pending weak declarations. */
5372 void
5373 weak_finish (void)
5375 tree t;
5377 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5379 tree alias_decl = TREE_PURPOSE (t);
5380 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5382 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5383 /* Remove alias_decl from the weak list, but leave entries for
5384 the target alone. */
5385 target = NULL_TREE;
5386 #ifndef ASM_OUTPUT_WEAKREF
5387 else if (! TREE_SYMBOL_REFERENCED (target))
5389 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5390 defined, otherwise we and weak_finish_1 would use
5391 different macros. */
5392 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5393 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5394 # else
5395 tree decl = find_decl (target);
5397 if (! decl)
5399 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5400 TREE_CODE (alias_decl), target,
5401 TREE_TYPE (alias_decl));
5403 DECL_EXTERNAL (decl) = 1;
5404 TREE_PUBLIC (decl) = 1;
5405 DECL_ARTIFICIAL (decl) = 1;
5406 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5407 TREE_USED (decl) = 1;
5410 weak_finish_1 (decl);
5411 # endif
5413 #endif
5416 tree *p;
5417 tree t2;
5419 /* Remove the alias and the target from the pending weak list
5420 so that we do not emit any .weak directives for the former,
5421 nor multiple .weak directives for the latter. */
5422 for (p = &weak_decls; (t2 = *p) ; )
5424 if (TREE_VALUE (t2) == alias_decl
5425 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5426 *p = TREE_CHAIN (t2);
5427 else
5428 p = &TREE_CHAIN (t2);
5431 /* Remove other weakrefs to the same target, to speed things up. */
5432 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5434 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5435 *p = TREE_CHAIN (t2);
5436 else
5437 p = &TREE_CHAIN (t2);
5442 for (t = weak_decls; t; t = TREE_CHAIN (t))
5444 tree decl = TREE_VALUE (t);
5446 weak_finish_1 (decl);
5450 /* Emit the assembly bits to indicate that DECL is globally visible. */
5452 static void
5453 globalize_decl (tree decl)
5456 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5457 if (DECL_WEAK (decl))
5459 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5460 tree *p, t;
5462 #ifdef ASM_WEAKEN_DECL
5463 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5464 #else
5465 ASM_WEAKEN_LABEL (asm_out_file, name);
5466 #endif
5468 /* Remove this function from the pending weak list so that
5469 we do not emit multiple .weak directives for it. */
5470 for (p = &weak_decls; (t = *p) ; )
5472 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5473 *p = TREE_CHAIN (t);
5474 else
5475 p = &TREE_CHAIN (t);
5478 /* Remove weakrefs to the same target from the pending weakref
5479 list, for the same reason. */
5480 for (p = &weakref_targets; (t = *p) ; )
5482 if (DECL_ASSEMBLER_NAME (decl)
5483 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5484 *p = TREE_CHAIN (t);
5485 else
5486 p = &TREE_CHAIN (t);
5489 return;
5491 #endif
5493 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5496 vec<alias_pair, va_gc> *alias_pairs;
5498 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5499 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5500 tree node is DECL to have the value of the tree node TARGET. */
5502 void
5503 do_assemble_alias (tree decl, tree target)
5505 /* Emulated TLS had better not get this var. */
5506 gcc_assert(!(!targetm.have_tls
5507 && TREE_CODE (decl) == VAR_DECL
5508 && DECL_THREAD_LOCAL_P (decl)));
5510 if (TREE_ASM_WRITTEN (decl))
5511 return;
5513 /* We must force creation of DECL_RTL for debug info generation, even though
5514 we don't use it here. */
5515 make_decl_rtl (decl);
5517 TREE_ASM_WRITTEN (decl) = 1;
5518 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5520 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5522 ultimate_transparent_alias_target (&target);
5524 if (!TREE_SYMBOL_REFERENCED (target))
5525 weakref_targets = tree_cons (decl, target, weakref_targets);
5527 #ifdef ASM_OUTPUT_WEAKREF
5528 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5529 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5530 IDENTIFIER_POINTER (target));
5531 #else
5532 if (!TARGET_SUPPORTS_WEAK)
5534 error_at (DECL_SOURCE_LOCATION (decl),
5535 "weakref is not supported in this configuration");
5536 return;
5538 #endif
5539 return;
5542 #ifdef ASM_OUTPUT_DEF
5543 /* Make name accessible from other files, if appropriate. */
5545 if (TREE_PUBLIC (decl))
5547 globalize_decl (decl);
5548 maybe_assemble_visibility (decl);
5550 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5552 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5553 if (targetm.has_ifunc_p ())
5554 ASM_OUTPUT_TYPE_DIRECTIVE
5555 (asm_out_file, IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5556 IFUNC_ASM_TYPE);
5557 else
5558 #endif
5559 error_at (DECL_SOURCE_LOCATION (decl),
5560 "ifunc is not supported on this target");
5563 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5564 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5565 # else
5566 ASM_OUTPUT_DEF (asm_out_file,
5567 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5568 IDENTIFIER_POINTER (target));
5569 # endif
5570 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5572 const char *name;
5573 tree *p, t;
5575 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5576 # ifdef ASM_WEAKEN_DECL
5577 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5578 # else
5579 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5580 # endif
5581 /* Remove this function from the pending weak list so that
5582 we do not emit multiple .weak directives for it. */
5583 for (p = &weak_decls; (t = *p) ; )
5584 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5585 *p = TREE_CHAIN (t);
5586 else
5587 p = &TREE_CHAIN (t);
5589 /* Remove weakrefs to the same target from the pending weakref
5590 list, for the same reason. */
5591 for (p = &weakref_targets; (t = *p) ; )
5593 if (DECL_ASSEMBLER_NAME (decl)
5594 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5595 *p = TREE_CHAIN (t);
5596 else
5597 p = &TREE_CHAIN (t);
5600 #endif
5603 /* Emit an assembler directive to make the symbol for DECL an alias to
5604 the symbol for TARGET. */
5606 void
5607 assemble_alias (tree decl, tree target)
5609 tree target_decl;
5611 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5613 tree alias = DECL_ASSEMBLER_NAME (decl);
5615 ultimate_transparent_alias_target (&target);
5617 if (alias == target)
5618 error ("weakref %q+D ultimately targets itself", decl);
5619 if (TREE_PUBLIC (decl))
5620 error ("weakref %q+D must have static linkage", decl);
5622 else
5624 #if !defined (ASM_OUTPUT_DEF)
5625 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5626 error_at (DECL_SOURCE_LOCATION (decl),
5627 "alias definitions not supported in this configuration");
5628 return;
5629 # else
5630 if (!DECL_WEAK (decl))
5632 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5633 error_at (DECL_SOURCE_LOCATION (decl),
5634 "ifunc is not supported in this configuration");
5635 else
5636 error_at (DECL_SOURCE_LOCATION (decl),
5637 "only weak aliases are supported in this configuration");
5638 return;
5640 # endif
5641 #endif
5643 TREE_USED (decl) = 1;
5645 /* Allow aliases to aliases. */
5646 if (TREE_CODE (decl) == FUNCTION_DECL)
5647 cgraph_get_create_node (decl)->symbol.alias = true;
5648 else
5649 varpool_node_for_decl (decl)->symbol.alias = true;
5651 /* If the target has already been emitted, we don't have to queue the
5652 alias. This saves a tad of memory. */
5653 if (cgraph_global_info_ready)
5654 target_decl = find_decl (target);
5655 else
5656 target_decl= NULL;
5657 if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5658 || cgraph_state >= CGRAPH_STATE_EXPANSION)
5659 do_assemble_alias (decl, target);
5660 else
5662 alias_pair p = {decl, target};
5663 vec_safe_push (alias_pairs, p);
5667 /* Record and output a table of translations from original function
5668 to its transaction aware clone. Note that tm_pure functions are
5669 considered to be their own clone. */
5671 static GTY((if_marked ("tree_map_marked_p"), param_is (struct tree_map)))
5672 htab_t tm_clone_hash;
5674 void
5675 record_tm_clone_pair (tree o, tree n)
5677 struct tree_map **slot, *h;
5679 if (tm_clone_hash == NULL)
5680 tm_clone_hash = htab_create_ggc (32, tree_map_hash, tree_map_eq, 0);
5682 h = ggc_alloc_tree_map ();
5683 h->hash = htab_hash_pointer (o);
5684 h->base.from = o;
5685 h->to = n;
5687 slot = (struct tree_map **)
5688 htab_find_slot_with_hash (tm_clone_hash, h, h->hash, INSERT);
5689 *slot = h;
5692 tree
5693 get_tm_clone_pair (tree o)
5695 if (tm_clone_hash)
5697 struct tree_map *h, in;
5699 in.base.from = o;
5700 in.hash = htab_hash_pointer (o);
5701 h = (struct tree_map *) htab_find_with_hash (tm_clone_hash,
5702 &in, in.hash);
5703 if (h)
5704 return h->to;
5706 return NULL_TREE;
5709 typedef struct tm_alias_pair
5711 unsigned int uid;
5712 tree from;
5713 tree to;
5714 } tm_alias_pair;
5717 /* Helper function for finish_tm_clone_pairs. Dump a hash table entry
5718 into a VEC in INFO. */
5720 static int
5721 dump_tm_clone_to_vec (void **slot, void *info)
5723 struct tree_map *map = (struct tree_map *) *slot;
5724 vec<tm_alias_pair> *tm_alias_pairs = (vec<tm_alias_pair> *) info;
5725 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
5726 tm_alias_pairs->safe_push (p);
5727 return 1;
5730 /* Dump the actual pairs to the .tm_clone_table section. */
5732 static void
5733 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
5735 unsigned i;
5736 tm_alias_pair *p;
5737 bool switched = false;
5739 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
5741 tree src = p->from;
5742 tree dst = p->to;
5743 struct cgraph_node *src_n = cgraph_get_node (src);
5744 struct cgraph_node *dst_n = cgraph_get_node (dst);
5746 /* The function ipa_tm_create_version() marks the clone as needed if
5747 the original function was needed. But we also mark the clone as
5748 needed if we ever called the clone indirectly through
5749 TM_GETTMCLONE. If neither of these are true, we didn't generate
5750 a clone, and we didn't call it indirectly... no sense keeping it
5751 in the clone table. */
5752 if (!dst_n || !dst_n->symbol.definition)
5753 continue;
5755 /* This covers the case where we have optimized the original
5756 function away, and only access the transactional clone. */
5757 if (!src_n || !src_n->symbol.definition)
5758 continue;
5760 if (!switched)
5762 switch_to_section (targetm.asm_out.tm_clone_table_section ());
5763 assemble_align (POINTER_SIZE);
5764 switched = true;
5767 assemble_integer (XEXP (DECL_RTL (src), 0),
5768 POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
5769 assemble_integer (XEXP (DECL_RTL (dst), 0),
5770 POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
5774 /* Provide a default for the tm_clone_table section. */
5776 section *
5777 default_clone_table_section (void)
5779 return get_named_section (NULL, ".tm_clone_table", 3);
5782 /* Helper comparison function for qsorting by the DECL_UID stored in
5783 alias_pair->emitted_diags. */
5785 static int
5786 tm_alias_pair_cmp (const void *x, const void *y)
5788 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
5789 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
5790 if (p1->uid < p2->uid)
5791 return -1;
5792 if (p1->uid > p2->uid)
5793 return 1;
5794 return 0;
5797 void
5798 finish_tm_clone_pairs (void)
5800 vec<tm_alias_pair> tm_alias_pairs = vNULL;
5802 if (tm_clone_hash == NULL)
5803 return;
5805 /* We need a determenistic order for the .tm_clone_table, otherwise
5806 we will get bootstrap comparison failures, so dump the hash table
5807 to a vector, sort it, and dump the vector. */
5809 /* Dump the hashtable to a vector. */
5810 htab_traverse_noresize (tm_clone_hash, dump_tm_clone_to_vec,
5811 (void *) &tm_alias_pairs);
5812 /* Sort it. */
5813 tm_alias_pairs.qsort (tm_alias_pair_cmp);
5815 /* Dump it. */
5816 dump_tm_clone_pairs (tm_alias_pairs);
5818 htab_delete (tm_clone_hash);
5819 tm_clone_hash = NULL;
5820 tm_alias_pairs.release ();
5824 /* Emit an assembler directive to set symbol for DECL visibility to
5825 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
5827 void
5828 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
5829 int vis ATTRIBUTE_UNUSED)
5831 #ifdef HAVE_GAS_HIDDEN
5832 static const char * const visibility_types[] = {
5833 NULL, "protected", "hidden", "internal"
5836 const char *name, *type;
5838 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5839 type = visibility_types[vis];
5841 fprintf (asm_out_file, "\t.%s\t", type);
5842 assemble_name (asm_out_file, name);
5843 fprintf (asm_out_file, "\n");
5844 #else
5845 if (!DECL_ARTIFICIAL (decl))
5846 warning (OPT_Wattributes, "visibility attribute not supported "
5847 "in this configuration; ignored");
5848 #endif
5851 /* A helper function to call assemble_visibility when needed for a decl. */
5854 maybe_assemble_visibility (tree decl)
5856 enum symbol_visibility vis = DECL_VISIBILITY (decl);
5858 if (vis != VISIBILITY_DEFAULT)
5860 targetm.asm_out.assemble_visibility (decl, vis);
5861 return 1;
5863 else
5864 return 0;
5867 /* Returns 1 if the target configuration supports defining public symbols
5868 so that one of them will be chosen at link time instead of generating a
5869 multiply-defined symbol error, whether through the use of weak symbols or
5870 a target-specific mechanism for having duplicates discarded. */
5873 supports_one_only (void)
5875 if (SUPPORTS_ONE_ONLY)
5876 return 1;
5877 return TARGET_SUPPORTS_WEAK;
5880 /* Set up DECL as a public symbol that can be defined in multiple
5881 translation units without generating a linker error. */
5883 void
5884 make_decl_one_only (tree decl, tree comdat_group)
5886 gcc_assert (TREE_CODE (decl) == VAR_DECL
5887 || TREE_CODE (decl) == FUNCTION_DECL);
5889 TREE_PUBLIC (decl) = 1;
5891 if (SUPPORTS_ONE_ONLY)
5893 #ifdef MAKE_DECL_ONE_ONLY
5894 MAKE_DECL_ONE_ONLY (decl);
5895 #endif
5896 DECL_COMDAT_GROUP (decl) = comdat_group;
5898 else if (TREE_CODE (decl) == VAR_DECL
5899 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node))
5900 DECL_COMMON (decl) = 1;
5901 else
5903 gcc_assert (TARGET_SUPPORTS_WEAK);
5904 DECL_WEAK (decl) = 1;
5908 void
5909 init_varasm_once (void)
5911 section_htab = htab_create_ggc (31, section_entry_hash,
5912 section_entry_eq, NULL);
5913 object_block_htab = htab_create_ggc (31, object_block_entry_hash,
5914 object_block_entry_eq, NULL);
5915 const_desc_htab = htab_create_ggc (1009, const_desc_hash,
5916 const_desc_eq, NULL);
5918 const_alias_set = new_alias_set ();
5919 shared_constant_pool = create_constant_pool ();
5921 #ifdef TEXT_SECTION_ASM_OP
5922 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
5923 TEXT_SECTION_ASM_OP);
5924 #endif
5926 #ifdef DATA_SECTION_ASM_OP
5927 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5928 DATA_SECTION_ASM_OP);
5929 #endif
5931 #ifdef SDATA_SECTION_ASM_OP
5932 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5933 SDATA_SECTION_ASM_OP);
5934 #endif
5936 #ifdef READONLY_DATA_SECTION_ASM_OP
5937 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
5938 READONLY_DATA_SECTION_ASM_OP);
5939 #endif
5941 #ifdef CTORS_SECTION_ASM_OP
5942 ctors_section = get_unnamed_section (0, output_section_asm_op,
5943 CTORS_SECTION_ASM_OP);
5944 #endif
5946 #ifdef DTORS_SECTION_ASM_OP
5947 dtors_section = get_unnamed_section (0, output_section_asm_op,
5948 DTORS_SECTION_ASM_OP);
5949 #endif
5951 #ifdef BSS_SECTION_ASM_OP
5952 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5953 output_section_asm_op,
5954 BSS_SECTION_ASM_OP);
5955 #endif
5957 #ifdef SBSS_SECTION_ASM_OP
5958 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5959 output_section_asm_op,
5960 SBSS_SECTION_ASM_OP);
5961 #endif
5963 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5964 | SECTION_COMMON, emit_tls_common);
5965 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5966 | SECTION_COMMON, emit_local);
5967 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5968 | SECTION_COMMON, emit_common);
5970 #if defined ASM_OUTPUT_ALIGNED_BSS
5971 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
5972 emit_bss);
5973 #endif
5975 targetm.asm_out.init_sections ();
5977 if (readonly_data_section == NULL)
5978 readonly_data_section = text_section;
5980 #ifdef ASM_OUTPUT_EXTERNAL
5981 pending_assemble_externals_set = pointer_set_create ();
5982 #endif
5985 enum tls_model
5986 decl_default_tls_model (const_tree decl)
5988 enum tls_model kind;
5989 bool is_local;
5991 is_local = targetm.binds_local_p (decl);
5992 if (!flag_shlib)
5994 if (is_local)
5995 kind = TLS_MODEL_LOCAL_EXEC;
5996 else
5997 kind = TLS_MODEL_INITIAL_EXEC;
6000 /* Local dynamic is inefficient when we're not combining the
6001 parts of the address. */
6002 else if (optimize && is_local)
6003 kind = TLS_MODEL_LOCAL_DYNAMIC;
6004 else
6005 kind = TLS_MODEL_GLOBAL_DYNAMIC;
6006 if (kind < flag_tls_default)
6007 kind = flag_tls_default;
6009 return kind;
6012 /* Select a set of attributes for section NAME based on the properties
6013 of DECL and whether or not RELOC indicates that DECL's initializer
6014 might contain runtime relocations.
6016 We make the section read-only and executable for a function decl,
6017 read-only for a const data decl, and writable for a non-const data decl. */
6019 unsigned int
6020 default_section_type_flags (tree decl, const char *name, int reloc)
6022 unsigned int flags;
6024 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6025 flags = SECTION_CODE;
6026 else if (decl)
6028 enum section_category category
6029 = categorize_decl_for_section (decl, reloc);
6030 if (decl_readonly_section_1 (category))
6031 flags = 0;
6032 else if (category == SECCAT_DATA_REL_RO
6033 || category == SECCAT_DATA_REL_RO_LOCAL)
6034 flags = SECTION_WRITE | SECTION_RELRO;
6035 else
6036 flags = SECTION_WRITE;
6038 else
6040 flags = SECTION_WRITE;
6041 if (strcmp (name, ".data.rel.ro") == 0
6042 || strcmp (name, ".data.rel.ro.local") == 0)
6043 flags |= SECTION_RELRO;
6046 if (decl && DECL_P (decl) && DECL_ONE_ONLY (decl))
6047 flags |= SECTION_LINKONCE;
6049 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6050 flags |= SECTION_TLS | SECTION_WRITE;
6052 if (strcmp (name, ".bss") == 0
6053 || strncmp (name, ".bss.", 5) == 0
6054 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6055 || strcmp (name, ".sbss") == 0
6056 || strncmp (name, ".sbss.", 6) == 0
6057 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6058 flags |= SECTION_BSS;
6060 if (strcmp (name, ".tdata") == 0
6061 || strncmp (name, ".tdata.", 7) == 0
6062 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6063 flags |= SECTION_TLS;
6065 if (strcmp (name, ".tbss") == 0
6066 || strncmp (name, ".tbss.", 6) == 0
6067 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6068 flags |= SECTION_TLS | SECTION_BSS;
6070 /* These three sections have special ELF types. They are neither
6071 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
6072 want to print a section type (@progbits or @nobits). If someone
6073 is silly enough to emit code or TLS variables to one of these
6074 sections, then don't handle them specially. */
6075 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6076 && (strcmp (name, ".init_array") == 0
6077 || strcmp (name, ".fini_array") == 0
6078 || strcmp (name, ".preinit_array") == 0))
6079 flags |= SECTION_NOTYPE;
6081 return flags;
6084 /* Return true if the target supports some form of global BSS,
6085 either through bss_noswitch_section, or by selecting a BSS
6086 section in TARGET_ASM_SELECT_SECTION. */
6088 bool
6089 have_global_bss_p (void)
6091 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6094 /* Output assembly to switch to section NAME with attribute FLAGS.
6095 Four variants for common object file formats. */
6097 void
6098 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6099 unsigned int flags ATTRIBUTE_UNUSED,
6100 tree decl ATTRIBUTE_UNUSED)
6102 /* Some object formats don't support named sections at all. The
6103 front-end should already have flagged this as an error. */
6104 gcc_unreachable ();
6107 #ifndef TLS_SECTION_ASM_FLAG
6108 #define TLS_SECTION_ASM_FLAG 'T'
6109 #endif
6111 void
6112 default_elf_asm_named_section (const char *name, unsigned int flags,
6113 tree decl ATTRIBUTE_UNUSED)
6115 char flagchars[10], *f = flagchars;
6117 /* If we have already declared this section, we can use an
6118 abbreviated form to switch back to it -- unless this section is
6119 part of a COMDAT groups, in which case GAS requires the full
6120 declaration every time. */
6121 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6122 && (flags & SECTION_DECLARED))
6124 fprintf (asm_out_file, "\t.section\t%s\n", name);
6125 return;
6128 if (!(flags & SECTION_DEBUG))
6129 *f++ = 'a';
6130 if (flags & SECTION_EXCLUDE)
6131 *f++ = 'e';
6132 if (flags & SECTION_WRITE)
6133 *f++ = 'w';
6134 if (flags & SECTION_CODE)
6135 *f++ = 'x';
6136 if (flags & SECTION_SMALL)
6137 *f++ = 's';
6138 if (flags & SECTION_MERGE)
6139 *f++ = 'M';
6140 if (flags & SECTION_STRINGS)
6141 *f++ = 'S';
6142 if (flags & SECTION_TLS)
6143 *f++ = TLS_SECTION_ASM_FLAG;
6144 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6145 *f++ = 'G';
6146 *f = '\0';
6148 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6150 if (!(flags & SECTION_NOTYPE))
6152 const char *type;
6153 const char *format;
6155 if (flags & SECTION_BSS)
6156 type = "nobits";
6157 else
6158 type = "progbits";
6160 format = ",@%s";
6161 /* On platforms that use "@" as the assembly comment character,
6162 use "%" instead. */
6163 if (strcmp (ASM_COMMENT_START, "@") == 0)
6164 format = ",%%%s";
6165 fprintf (asm_out_file, format, type);
6167 if (flags & SECTION_ENTSIZE)
6168 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6169 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6171 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6172 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6173 else
6174 fprintf (asm_out_file, ",%s,comdat",
6175 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6179 putc ('\n', asm_out_file);
6182 void
6183 default_coff_asm_named_section (const char *name, unsigned int flags,
6184 tree decl ATTRIBUTE_UNUSED)
6186 char flagchars[8], *f = flagchars;
6188 if (flags & SECTION_WRITE)
6189 *f++ = 'w';
6190 if (flags & SECTION_CODE)
6191 *f++ = 'x';
6192 *f = '\0';
6194 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6197 void
6198 default_pe_asm_named_section (const char *name, unsigned int flags,
6199 tree decl)
6201 default_coff_asm_named_section (name, flags, decl);
6203 if (flags & SECTION_LINKONCE)
6205 /* Functions may have been compiled at various levels of
6206 optimization so we can't use `same_size' here.
6207 Instead, have the linker pick one. */
6208 fprintf (asm_out_file, "\t.linkonce %s\n",
6209 (flags & SECTION_CODE ? "discard" : "same_size"));
6213 /* The lame default section selector. */
6215 section *
6216 default_select_section (tree decl, int reloc,
6217 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6219 if (DECL_P (decl))
6221 if (decl_readonly_section (decl, reloc))
6222 return readonly_data_section;
6224 else if (TREE_CODE (decl) == CONSTRUCTOR)
6226 if (! ((flag_pic && reloc)
6227 || !TREE_READONLY (decl)
6228 || TREE_SIDE_EFFECTS (decl)
6229 || !TREE_CONSTANT (decl)))
6230 return readonly_data_section;
6232 else if (TREE_CODE (decl) == STRING_CST)
6233 return readonly_data_section;
6234 else if (! (flag_pic && reloc))
6235 return readonly_data_section;
6237 return data_section;
6240 enum section_category
6241 categorize_decl_for_section (const_tree decl, int reloc)
6243 enum section_category ret;
6245 if (TREE_CODE (decl) == FUNCTION_DECL)
6246 return SECCAT_TEXT;
6247 else if (TREE_CODE (decl) == STRING_CST)
6249 if (flag_mudflap
6250 || (flag_asan && asan_protect_global (CONST_CAST_TREE (decl))))
6251 /* or !flag_merge_constants */
6252 return SECCAT_RODATA;
6253 else
6254 return SECCAT_RODATA_MERGE_STR;
6256 else if (TREE_CODE (decl) == VAR_DECL)
6258 if (bss_initializer_p (decl))
6259 ret = SECCAT_BSS;
6260 else if (! TREE_READONLY (decl)
6261 || TREE_SIDE_EFFECTS (decl)
6262 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
6264 /* Here the reloc_rw_mask is not testing whether the section should
6265 be read-only or not, but whether the dynamic link will have to
6266 do something. If so, we wish to segregate the data in order to
6267 minimize cache misses inside the dynamic linker. */
6268 if (reloc & targetm.asm_out.reloc_rw_mask ())
6269 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6270 else
6271 ret = SECCAT_DATA;
6273 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6274 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6275 else if (reloc || flag_merge_constants < 2 || flag_mudflap
6276 || (flag_asan && asan_protect_global (CONST_CAST_TREE (decl))))
6277 /* C and C++ don't allow different variables to share the same
6278 location. -fmerge-all-constants allows even that (at the
6279 expense of not conforming). */
6280 ret = SECCAT_RODATA;
6281 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6282 ret = SECCAT_RODATA_MERGE_STR_INIT;
6283 else
6284 ret = SECCAT_RODATA_MERGE_CONST;
6286 else if (TREE_CODE (decl) == CONSTRUCTOR)
6288 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6289 || TREE_SIDE_EFFECTS (decl)
6290 || ! TREE_CONSTANT (decl))
6291 ret = SECCAT_DATA;
6292 else
6293 ret = SECCAT_RODATA;
6295 else
6296 ret = SECCAT_RODATA;
6298 /* There are no read-only thread-local sections. */
6299 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6301 /* Note that this would be *just* SECCAT_BSS, except that there's
6302 no concept of a read-only thread-local-data section. */
6303 if (ret == SECCAT_BSS
6304 || (flag_zero_initialized_in_bss
6305 && initializer_zerop (DECL_INITIAL (decl))))
6306 ret = SECCAT_TBSS;
6307 else
6308 ret = SECCAT_TDATA;
6311 /* If the target uses small data sections, select it. */
6312 else if (targetm.in_small_data_p (decl))
6314 if (ret == SECCAT_BSS)
6315 ret = SECCAT_SBSS;
6316 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6317 ret = SECCAT_SRODATA;
6318 else
6319 ret = SECCAT_SDATA;
6322 return ret;
6325 static bool
6326 decl_readonly_section_1 (enum section_category category)
6328 switch (category)
6330 case SECCAT_RODATA:
6331 case SECCAT_RODATA_MERGE_STR:
6332 case SECCAT_RODATA_MERGE_STR_INIT:
6333 case SECCAT_RODATA_MERGE_CONST:
6334 case SECCAT_SRODATA:
6335 return true;
6336 default:
6337 return false;
6341 bool
6342 decl_readonly_section (const_tree decl, int reloc)
6344 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6347 /* Select a section based on the above categorization. */
6349 section *
6350 default_elf_select_section (tree decl, int reloc,
6351 unsigned HOST_WIDE_INT align)
6353 const char *sname;
6354 switch (categorize_decl_for_section (decl, reloc))
6356 case SECCAT_TEXT:
6357 /* We're not supposed to be called on FUNCTION_DECLs. */
6358 gcc_unreachable ();
6359 case SECCAT_RODATA:
6360 return readonly_data_section;
6361 case SECCAT_RODATA_MERGE_STR:
6362 return mergeable_string_section (decl, align, 0);
6363 case SECCAT_RODATA_MERGE_STR_INIT:
6364 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6365 case SECCAT_RODATA_MERGE_CONST:
6366 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6367 case SECCAT_SRODATA:
6368 sname = ".sdata2";
6369 break;
6370 case SECCAT_DATA:
6371 return data_section;
6372 case SECCAT_DATA_REL:
6373 sname = ".data.rel";
6374 break;
6375 case SECCAT_DATA_REL_LOCAL:
6376 sname = ".data.rel.local";
6377 break;
6378 case SECCAT_DATA_REL_RO:
6379 sname = ".data.rel.ro";
6380 break;
6381 case SECCAT_DATA_REL_RO_LOCAL:
6382 sname = ".data.rel.ro.local";
6383 break;
6384 case SECCAT_SDATA:
6385 sname = ".sdata";
6386 break;
6387 case SECCAT_TDATA:
6388 sname = ".tdata";
6389 break;
6390 case SECCAT_BSS:
6391 if (bss_section)
6392 return bss_section;
6393 sname = ".bss";
6394 break;
6395 case SECCAT_SBSS:
6396 sname = ".sbss";
6397 break;
6398 case SECCAT_TBSS:
6399 sname = ".tbss";
6400 break;
6401 default:
6402 gcc_unreachable ();
6405 return get_named_section (decl, sname, reloc);
6408 /* Construct a unique section name based on the decl name and the
6409 categorization performed above. */
6411 void
6412 default_unique_section (tree decl, int reloc)
6414 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6415 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6416 const char *prefix, *name, *linkonce;
6417 char *string;
6419 switch (categorize_decl_for_section (decl, reloc))
6421 case SECCAT_TEXT:
6422 prefix = one_only ? ".t" : ".text";
6423 break;
6424 case SECCAT_RODATA:
6425 case SECCAT_RODATA_MERGE_STR:
6426 case SECCAT_RODATA_MERGE_STR_INIT:
6427 case SECCAT_RODATA_MERGE_CONST:
6428 prefix = one_only ? ".r" : ".rodata";
6429 break;
6430 case SECCAT_SRODATA:
6431 prefix = one_only ? ".s2" : ".sdata2";
6432 break;
6433 case SECCAT_DATA:
6434 prefix = one_only ? ".d" : ".data";
6435 break;
6436 case SECCAT_DATA_REL:
6437 prefix = one_only ? ".d.rel" : ".data.rel";
6438 break;
6439 case SECCAT_DATA_REL_LOCAL:
6440 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6441 break;
6442 case SECCAT_DATA_REL_RO:
6443 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6444 break;
6445 case SECCAT_DATA_REL_RO_LOCAL:
6446 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6447 break;
6448 case SECCAT_SDATA:
6449 prefix = one_only ? ".s" : ".sdata";
6450 break;
6451 case SECCAT_BSS:
6452 prefix = one_only ? ".b" : ".bss";
6453 break;
6454 case SECCAT_SBSS:
6455 prefix = one_only ? ".sb" : ".sbss";
6456 break;
6457 case SECCAT_TDATA:
6458 prefix = one_only ? ".td" : ".tdata";
6459 break;
6460 case SECCAT_TBSS:
6461 prefix = one_only ? ".tb" : ".tbss";
6462 break;
6463 default:
6464 gcc_unreachable ();
6467 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
6468 name = targetm.strip_name_encoding (name);
6470 /* If we're using one_only, then there needs to be a .gnu.linkonce
6471 prefix to the section name. */
6472 linkonce = one_only ? ".gnu.linkonce" : "";
6474 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6476 DECL_SECTION_NAME (decl) = build_string (strlen (string), string);
6479 /* Like compute_reloc_for_constant, except for an RTX. The return value
6480 is a mask for which bit 1 indicates a global relocation, and bit 0
6481 indicates a local relocation. */
6483 static int
6484 compute_reloc_for_rtx_1 (rtx *xp, void *data)
6486 int *preloc = (int *) data;
6487 rtx x = *xp;
6489 switch (GET_CODE (x))
6491 case SYMBOL_REF:
6492 *preloc |= SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6493 break;
6494 case LABEL_REF:
6495 *preloc |= 1;
6496 break;
6497 default:
6498 break;
6501 return 0;
6504 static int
6505 compute_reloc_for_rtx (rtx x)
6507 int reloc;
6509 switch (GET_CODE (x))
6511 case CONST:
6512 case SYMBOL_REF:
6513 case LABEL_REF:
6514 reloc = 0;
6515 for_each_rtx (&x, compute_reloc_for_rtx_1, &reloc);
6516 return reloc;
6518 default:
6519 return 0;
6523 section *
6524 default_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
6525 rtx x,
6526 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6528 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6529 return data_section;
6530 else
6531 return readonly_data_section;
6534 section *
6535 default_elf_select_rtx_section (enum machine_mode mode, rtx x,
6536 unsigned HOST_WIDE_INT align)
6538 int reloc = compute_reloc_for_rtx (x);
6540 /* ??? Handle small data here somehow. */
6542 if (reloc & targetm.asm_out.reloc_rw_mask ())
6544 if (reloc == 1)
6545 return get_named_section (NULL, ".data.rel.ro.local", 1);
6546 else
6547 return get_named_section (NULL, ".data.rel.ro", 3);
6550 return mergeable_constant_section (mode, align, 0);
6553 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6555 void
6556 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6558 rtx symbol;
6559 int flags;
6561 /* Careful not to prod global register variables. */
6562 if (!MEM_P (rtl))
6563 return;
6564 symbol = XEXP (rtl, 0);
6565 if (GET_CODE (symbol) != SYMBOL_REF)
6566 return;
6568 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6569 if (TREE_CODE (decl) == FUNCTION_DECL)
6570 flags |= SYMBOL_FLAG_FUNCTION;
6571 if (targetm.binds_local_p (decl))
6572 flags |= SYMBOL_FLAG_LOCAL;
6573 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6574 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6575 else if (targetm.in_small_data_p (decl))
6576 flags |= SYMBOL_FLAG_SMALL;
6577 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6578 being PUBLIC, the thing *must* be defined in this translation unit.
6579 Prevent this buglet from being propagated into rtl code as well. */
6580 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6581 flags |= SYMBOL_FLAG_EXTERNAL;
6583 SYMBOL_REF_FLAGS (symbol) = flags;
6586 /* By default, we do nothing for encode_section_info, so we need not
6587 do anything but discard the '*' marker. */
6589 const char *
6590 default_strip_name_encoding (const char *str)
6592 return str + (*str == '*');
6595 #ifdef ASM_OUTPUT_DEF
6596 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6597 anchor relative to ".", the current section position. */
6599 void
6600 default_asm_output_anchor (rtx symbol)
6602 char buffer[100];
6604 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6605 SYMBOL_REF_BLOCK_OFFSET (symbol));
6606 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6608 #endif
6610 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6612 bool
6613 default_use_anchors_for_symbol_p (const_rtx symbol)
6615 section *sect;
6616 tree decl;
6618 /* Don't use anchors for mergeable sections. The linker might move
6619 the objects around. */
6620 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6621 if (sect->common.flags & SECTION_MERGE)
6622 return false;
6624 /* Don't use anchors for small data sections. The small data register
6625 acts as an anchor for such sections. */
6626 if (sect->common.flags & SECTION_SMALL)
6627 return false;
6629 decl = SYMBOL_REF_DECL (symbol);
6630 if (decl && DECL_P (decl))
6632 /* Don't use section anchors for decls that might be defined or
6633 usurped by other modules. */
6634 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6635 return false;
6637 /* Don't use section anchors for decls that will be placed in a
6638 small data section. */
6639 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6640 one above. The problem is that we only use SECTION_SMALL for
6641 sections that should be marked as small in the section directive. */
6642 if (targetm.in_small_data_p (decl))
6643 return false;
6645 return true;
6648 /* Return true when RESOLUTION indicate that symbol will be bound to the
6649 definition provided by current .o file. */
6651 static bool
6652 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
6654 return (resolution == LDPR_PREVAILING_DEF
6655 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6656 || resolution == LDPR_PREVAILING_DEF_IRONLY);
6659 /* Return true when RESOLUTION indicate that symbol will be bound locally
6660 within current executable or DSO. */
6662 static bool
6663 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
6665 return (resolution == LDPR_PREVAILING_DEF
6666 || resolution == LDPR_PREVAILING_DEF_IRONLY
6667 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6668 || resolution == LDPR_PREEMPTED_REG
6669 || resolution == LDPR_PREEMPTED_IR
6670 || resolution == LDPR_RESOLVED_IR
6671 || resolution == LDPR_RESOLVED_EXEC);
6674 /* Assume ELF-ish defaults, since that's pretty much the most liberal
6675 wrt cross-module name binding. */
6677 bool
6678 default_binds_local_p (const_tree exp)
6680 return default_binds_local_p_1 (exp, flag_shlib);
6683 bool
6684 default_binds_local_p_1 (const_tree exp, int shlib)
6686 bool local_p;
6687 bool resolved_locally = false;
6688 bool resolved_to_local_def = false;
6690 /* With resolution file in hands, take look into resolutions.
6691 We can't just return true for resolved_locally symbols,
6692 because dynamic linking might overwrite symbols
6693 in shared libraries. */
6694 if (TREE_CODE (exp) == VAR_DECL && TREE_PUBLIC (exp)
6695 && (TREE_STATIC (exp) || DECL_EXTERNAL (exp)))
6697 struct varpool_node *vnode = varpool_get_node (exp);
6698 if (vnode && resolution_local_p (vnode->symbol.resolution))
6699 resolved_locally = true;
6700 if (vnode
6701 && resolution_to_local_definition_p (vnode->symbol.resolution))
6702 resolved_to_local_def = true;
6704 else if (TREE_CODE (exp) == FUNCTION_DECL && TREE_PUBLIC (exp))
6706 struct cgraph_node *node = cgraph_get_node (exp);
6707 if (node
6708 && resolution_local_p (node->symbol.resolution))
6709 resolved_locally = true;
6710 if (node
6711 && resolution_to_local_definition_p (node->symbol.resolution))
6712 resolved_to_local_def = true;
6715 /* A non-decl is an entry in the constant pool. */
6716 if (!DECL_P (exp))
6717 local_p = true;
6718 /* Weakrefs may not bind locally, even though the weakref itself is always
6719 static and therefore local. Similarly, the resolver for ifunc functions
6720 might resolve to a non-local function.
6721 FIXME: We can resolve the weakref case more curefuly by looking at the
6722 weakref alias. */
6723 else if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
6724 || (TREE_CODE (exp) == FUNCTION_DECL
6725 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
6726 local_p = false;
6727 /* Static variables are always local. */
6728 else if (! TREE_PUBLIC (exp))
6729 local_p = true;
6730 /* A variable is local if the user has said explicitly that it will
6731 be. */
6732 else if ((DECL_VISIBILITY_SPECIFIED (exp)
6733 || resolved_to_local_def)
6734 && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6735 local_p = true;
6736 /* Variables defined outside this object might not be local. */
6737 else if (DECL_EXTERNAL (exp) && !resolved_locally)
6738 local_p = false;
6739 /* If defined in this object and visibility is not default, must be
6740 local. */
6741 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6742 local_p = true;
6743 /* Default visibility weak data can be overridden by a strong symbol
6744 in another module and so are not local. */
6745 else if (DECL_WEAK (exp)
6746 && !resolved_locally)
6747 local_p = false;
6748 /* If PIC, then assume that any global name can be overridden by
6749 symbols resolved from other modules. */
6750 else if (shlib)
6751 local_p = false;
6752 /* Uninitialized COMMON variable may be unified with symbols
6753 resolved from other modules. */
6754 else if (DECL_COMMON (exp)
6755 && !resolved_locally
6756 && (DECL_INITIAL (exp) == NULL
6757 || DECL_INITIAL (exp) == error_mark_node))
6758 local_p = false;
6759 /* Otherwise we're left with initialized (or non-common) global data
6760 which is of necessity defined locally. */
6761 else
6762 local_p = true;
6764 return local_p;
6767 /* Return true when references to DECL must bind to current definition in
6768 final executable.
6770 The condition is usually equivalent to whether the function binds to the
6771 current module (shared library or executable), that is to binds_local_p.
6772 We use this fact to avoid need for another target hook and implement
6773 the logic using binds_local_p and just special cases where
6774 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
6775 the weak definitions (that can be overwritten at linktime by other
6776 definition from different object file) and when resolution info is available
6777 we simply use the knowledge passed to us by linker plugin. */
6778 bool
6779 decl_binds_to_current_def_p (tree decl)
6781 gcc_assert (DECL_P (decl));
6782 if (!targetm.binds_local_p (decl))
6783 return false;
6784 if (!TREE_PUBLIC (decl))
6785 return true;
6786 /* When resolution is available, just use it. */
6787 if (TREE_CODE (decl) == VAR_DECL
6788 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl)))
6790 struct varpool_node *vnode = varpool_get_node (decl);
6791 if (vnode
6792 && vnode->symbol.resolution != LDPR_UNKNOWN)
6793 return resolution_to_local_definition_p (vnode->symbol.resolution);
6795 else if (TREE_CODE (decl) == FUNCTION_DECL)
6797 struct cgraph_node *node = cgraph_get_node (decl);
6798 if (node
6799 && node->symbol.resolution != LDPR_UNKNOWN)
6800 return resolution_to_local_definition_p (node->symbol.resolution);
6802 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
6803 binds locally but still can be overwritten), DECL_COMMON (can be merged
6804 with a non-common definition somewhere in the same module) or
6805 DECL_EXTERNAL.
6806 This rely on fact that binds_local_p behave as decl_replaceable_p
6807 for all other declaration types. */
6808 if (DECL_WEAK (decl))
6809 return false;
6810 if (DECL_COMMON (decl)
6811 && (DECL_INITIAL (decl) == NULL
6812 || DECL_INITIAL (decl) == error_mark_node))
6813 return false;
6814 if (DECL_EXTERNAL (decl))
6815 return false;
6816 return true;
6819 /* A replaceable function or variable is one which may be replaced
6820 at link-time with an entirely different definition, provided that the
6821 replacement has the same type. For example, functions declared
6822 with __attribute__((weak)) on most systems are replaceable.
6824 COMDAT functions are not replaceable, since all definitions of the
6825 function must be equivalent. It is important that COMDAT functions
6826 not be treated as replaceable so that use of C++ template
6827 instantiations is not penalized. */
6829 bool
6830 decl_replaceable_p (tree decl)
6832 gcc_assert (DECL_P (decl));
6833 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
6834 return false;
6835 return !decl_binds_to_current_def_p (decl);
6838 /* Default function to output code that will globalize a label. A
6839 target must define GLOBAL_ASM_OP or provide its own function to
6840 globalize a label. */
6841 #ifdef GLOBAL_ASM_OP
6842 void
6843 default_globalize_label (FILE * stream, const char *name)
6845 fputs (GLOBAL_ASM_OP, stream);
6846 assemble_name (stream, name);
6847 putc ('\n', stream);
6849 #endif /* GLOBAL_ASM_OP */
6851 /* Default function to output code that will globalize a declaration. */
6852 void
6853 default_globalize_decl_name (FILE * stream, tree decl)
6855 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
6856 targetm.asm_out.globalize_label (stream, name);
6859 /* Default function to output a label for unwind information. The
6860 default is to do nothing. A target that needs nonlocal labels for
6861 unwind information must provide its own function to do this. */
6862 void
6863 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
6864 tree decl ATTRIBUTE_UNUSED,
6865 int for_eh ATTRIBUTE_UNUSED,
6866 int empty ATTRIBUTE_UNUSED)
6870 /* Default function to output a label to divide up the exception table.
6871 The default is to do nothing. A target that needs/wants to divide
6872 up the table must provide it's own function to do this. */
6873 void
6874 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
6878 /* This is how to output an internal numbered label where PREFIX is
6879 the class of label and LABELNO is the number within the class. */
6881 void
6882 default_generate_internal_label (char *buf, const char *prefix,
6883 unsigned long labelno)
6885 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6888 /* This is how to output an internal numbered label where PREFIX is
6889 the class of label and LABELNO is the number within the class. */
6891 void
6892 default_internal_label (FILE *stream, const char *prefix,
6893 unsigned long labelno)
6895 char *const buf = (char *) alloca (40 + strlen (prefix));
6896 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6897 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
6901 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
6903 void
6904 default_asm_declare_constant_name (FILE *file, const char *name,
6905 const_tree exp ATTRIBUTE_UNUSED,
6906 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
6908 assemble_label (file, name);
6911 /* This is the default behavior at the beginning of a file. It's
6912 controlled by two other target-hook toggles. */
6913 void
6914 default_file_start (void)
6916 if (targetm.asm_file_start_app_off
6917 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
6918 fputs (ASM_APP_OFF, asm_out_file);
6920 if (targetm.asm_file_start_file_directive)
6921 output_file_directive (asm_out_file, main_input_filename);
6924 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
6925 which emits a special section directive used to indicate whether or
6926 not this object file needs an executable stack. This is primarily
6927 a GNU extension to ELF but could be used on other targets. */
6929 int trampolines_created;
6931 void
6932 file_end_indicate_exec_stack (void)
6934 unsigned int flags = SECTION_DEBUG;
6935 if (trampolines_created)
6936 flags |= SECTION_CODE;
6938 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
6941 /* Emit a special section directive to indicate that this object file
6942 was compiled with -fsplit-stack. This is used to let the linker
6943 detect calls between split-stack code and non-split-stack code, so
6944 that it can modify the split-stack code to allocate a sufficiently
6945 large stack. We emit another special section if there are any
6946 functions in this file which have the no_split_stack attribute, to
6947 prevent the linker from warning about being unable to convert the
6948 functions if they call non-split-stack code. */
6950 void
6951 file_end_indicate_split_stack (void)
6953 if (flag_split_stack)
6955 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
6956 NULL));
6957 if (saw_no_split_stack)
6958 switch_to_section (get_section (".note.GNU-no-split-stack",
6959 SECTION_DEBUG, NULL));
6963 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
6964 a get_unnamed_section callback. */
6966 void
6967 output_section_asm_op (const void *directive)
6969 fprintf (asm_out_file, "%s\n", (const char *) directive);
6972 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
6973 the current section is NEW_SECTION. */
6975 void
6976 switch_to_section (section *new_section)
6978 if (in_section == new_section)
6979 return;
6981 if (new_section->common.flags & SECTION_FORGET)
6982 in_section = NULL;
6983 else
6984 in_section = new_section;
6986 switch (SECTION_STYLE (new_section))
6988 case SECTION_NAMED:
6989 targetm.asm_out.named_section (new_section->named.name,
6990 new_section->named.common.flags,
6991 new_section->named.decl);
6992 break;
6994 case SECTION_UNNAMED:
6995 new_section->unnamed.callback (new_section->unnamed.data);
6996 break;
6998 case SECTION_NOSWITCH:
6999 gcc_unreachable ();
7000 break;
7003 new_section->common.flags |= SECTION_DECLARED;
7006 /* If block symbol SYMBOL has not yet been assigned an offset, place
7007 it at the end of its block. */
7009 void
7010 place_block_symbol (rtx symbol)
7012 unsigned HOST_WIDE_INT size, mask, offset;
7013 struct constant_descriptor_rtx *desc;
7014 unsigned int alignment;
7015 struct object_block *block;
7016 tree decl;
7018 gcc_assert (SYMBOL_REF_BLOCK (symbol));
7019 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7020 return;
7022 /* Work out the symbol's size and alignment. */
7023 if (CONSTANT_POOL_ADDRESS_P (symbol))
7025 desc = SYMBOL_REF_CONSTANT (symbol);
7026 alignment = desc->align;
7027 size = GET_MODE_SIZE (desc->mode);
7029 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7031 decl = SYMBOL_REF_DECL (symbol);
7032 alignment = DECL_ALIGN (decl);
7033 size = get_constant_size (DECL_INITIAL (decl));
7034 if (flag_asan
7035 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7036 && asan_protect_global (DECL_INITIAL (decl)))
7037 size += asan_red_zone_size (size);
7039 else
7041 decl = SYMBOL_REF_DECL (symbol);
7042 alignment = get_variable_align (decl);
7043 size = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
7044 if (flag_asan && asan_protect_global (decl))
7046 size += asan_red_zone_size (size);
7047 alignment = MAX (alignment,
7048 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7052 /* Calculate the object's offset from the start of the block. */
7053 block = SYMBOL_REF_BLOCK (symbol);
7054 mask = alignment / BITS_PER_UNIT - 1;
7055 offset = (block->size + mask) & ~mask;
7056 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7058 /* Record the block's new alignment and size. */
7059 block->alignment = MAX (block->alignment, alignment);
7060 block->size = offset + size;
7062 vec_safe_push (block->objects, symbol);
7065 /* Return the anchor that should be used to address byte offset OFFSET
7066 from the first object in BLOCK. MODEL is the TLS model used
7067 to access it. */
7070 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7071 enum tls_model model)
7073 char label[100];
7074 unsigned int begin, middle, end;
7075 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7076 rtx anchor;
7078 /* Work out the anchor's offset. Use an offset of 0 for the first
7079 anchor so that we don't pessimize the case where we take the address
7080 of a variable at the beginning of the block. This is particularly
7081 useful when a block has only one variable assigned to it.
7083 We try to place anchors RANGE bytes apart, so there can then be
7084 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7085 a ptr_mode offset. With some target settings, the lowest such
7086 anchor might be out of range for the lowest ptr_mode offset;
7087 likewise the highest anchor for the highest offset. Use anchors
7088 at the extreme ends of the ptr_mode range in such cases.
7090 All arithmetic uses unsigned integers in order to avoid
7091 signed overflow. */
7092 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7093 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7094 range = max_offset - min_offset + 1;
7095 if (range == 0)
7096 offset = 0;
7097 else
7099 bias = 1 << (GET_MODE_BITSIZE (ptr_mode) - 1);
7100 if (offset < 0)
7102 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7103 delta -= delta % range;
7104 if (delta > bias)
7105 delta = bias;
7106 offset = (HOST_WIDE_INT) (-delta);
7108 else
7110 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7111 delta -= delta % range;
7112 if (delta > bias - 1)
7113 delta = bias - 1;
7114 offset = (HOST_WIDE_INT) delta;
7118 /* Do a binary search to see if there's already an anchor we can use.
7119 Set BEGIN to the new anchor's index if not. */
7120 begin = 0;
7121 end = vec_safe_length (block->anchors);
7122 while (begin != end)
7124 middle = (end + begin) / 2;
7125 anchor = (*block->anchors)[middle];
7126 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7127 end = middle;
7128 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7129 begin = middle + 1;
7130 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7131 end = middle;
7132 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7133 begin = middle + 1;
7134 else
7135 return anchor;
7138 /* Create a new anchor with a unique label. */
7139 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7140 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7141 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7142 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7144 /* Insert it at index BEGIN. */
7145 vec_safe_insert (block->anchors, begin, anchor);
7146 return anchor;
7149 /* Output the objects in BLOCK. */
7151 static void
7152 output_object_block (struct object_block *block)
7154 struct constant_descriptor_rtx *desc;
7155 unsigned int i;
7156 HOST_WIDE_INT offset;
7157 tree decl;
7158 rtx symbol;
7160 if (!block->objects)
7161 return;
7163 /* Switch to the section and make sure that the first byte is
7164 suitably aligned. */
7165 switch_to_section (block->sect);
7166 assemble_align (block->alignment);
7168 /* Define the values of all anchors relative to the current section
7169 position. */
7170 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7171 targetm.asm_out.output_anchor (symbol);
7173 /* Output the objects themselves. */
7174 offset = 0;
7175 FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7177 /* Move to the object's offset, padding with zeros if necessary. */
7178 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7179 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7180 if (CONSTANT_POOL_ADDRESS_P (symbol))
7182 desc = SYMBOL_REF_CONSTANT (symbol);
7183 output_constant_pool_1 (desc, 1);
7184 offset += GET_MODE_SIZE (desc->mode);
7186 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7188 HOST_WIDE_INT size;
7189 decl = SYMBOL_REF_DECL (symbol);
7190 assemble_constant_contents (DECL_INITIAL (decl), XSTR (symbol, 0),
7191 DECL_ALIGN (decl));
7192 size = get_constant_size (DECL_INITIAL (decl));
7193 offset += size;
7194 if (flag_asan
7195 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7196 && asan_protect_global (DECL_INITIAL (decl)))
7198 size = asan_red_zone_size (size);
7199 assemble_zeros (size);
7200 offset += size;
7203 else
7205 HOST_WIDE_INT size;
7206 decl = SYMBOL_REF_DECL (symbol);
7207 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7208 size = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
7209 offset += size;
7210 if (flag_asan && asan_protect_global (decl))
7212 size = asan_red_zone_size (size);
7213 assemble_zeros (size);
7214 offset += size;
7220 /* A htab_traverse callback used to call output_object_block for
7221 each member of object_block_htab. */
7223 static int
7224 output_object_block_htab (void **slot, void *data ATTRIBUTE_UNUSED)
7226 output_object_block ((struct object_block *) (*slot));
7227 return 1;
7230 /* Output the definitions of all object_blocks. */
7232 void
7233 output_object_blocks (void)
7235 htab_traverse (object_block_htab, output_object_block_htab, NULL);
7238 /* This function provides a possible implementation of the
7239 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7240 by -frecord-gcc-switches it creates a new mergeable, string section in the
7241 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7242 contains the switches in ASCII format.
7244 FIXME: This code does not correctly handle double quote characters
7245 that appear inside strings, (it strips them rather than preserving them).
7246 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7247 characters - instead it treats them as sub-string separators. Since
7248 we want to emit NUL strings terminators into the object file we have to use
7249 ASM_OUTPUT_SKIP. */
7252 elf_record_gcc_switches (print_switch_type type, const char * name)
7254 switch (type)
7256 case SWITCH_TYPE_PASSED:
7257 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7258 ASM_OUTPUT_SKIP (asm_out_file, (unsigned HOST_WIDE_INT) 1);
7259 break;
7261 case SWITCH_TYPE_DESCRIPTIVE:
7262 if (name == NULL)
7264 /* Distinguish between invocations where name is NULL. */
7265 static bool started = false;
7267 if (!started)
7269 section * sec;
7271 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7272 SECTION_DEBUG
7273 | SECTION_MERGE
7274 | SECTION_STRINGS
7275 | (SECTION_ENTSIZE & 1),
7276 NULL);
7277 switch_to_section (sec);
7278 started = true;
7282 default:
7283 break;
7286 /* The return value is currently ignored by the caller, but must be 0.
7287 For -fverbose-asm the return value would be the number of characters
7288 emitted into the assembler file. */
7289 return 0;
7292 /* Emit text to declare externally defined symbols. It is needed to
7293 properly support non-default visibility. */
7294 void
7295 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7296 tree decl,
7297 const char *name ATTRIBUTE_UNUSED)
7299 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7300 set in order to avoid putting out names that are never really
7301 used. */
7302 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7303 && targetm.binds_local_p (decl))
7304 maybe_assemble_visibility (decl);
7307 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7309 void
7310 default_asm_output_source_filename (FILE *file, const char *name)
7312 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7313 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7314 #else
7315 fprintf (file, "\t.file\t");
7316 output_quoted_string (file, name);
7317 putc ('\n', file);
7318 #endif
7321 /* Output a file name in the form wanted by System V. */
7323 void
7324 output_file_directive (FILE *asm_file, const char *input_name)
7326 int len;
7327 const char *na;
7329 if (input_name == NULL)
7330 input_name = "<stdin>";
7331 else
7332 input_name = remap_debug_filename (input_name);
7334 len = strlen (input_name);
7335 na = input_name + len;
7337 /* NA gets INPUT_NAME sans directory names. */
7338 while (na > input_name)
7340 if (IS_DIR_SEPARATOR (na[-1]))
7341 break;
7342 na--;
7345 targetm.asm_out.output_source_filename (asm_file, na);
7348 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7349 EXP. */
7351 make_debug_expr_from_rtl (const_rtx exp)
7353 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7354 enum machine_mode mode = GET_MODE (exp);
7355 rtx dval;
7357 DECL_ARTIFICIAL (ddecl) = 1;
7358 if (REG_P (exp) && REG_EXPR (exp))
7359 type = TREE_TYPE (REG_EXPR (exp));
7360 else if (MEM_P (exp) && MEM_EXPR (exp))
7361 type = TREE_TYPE (MEM_EXPR (exp));
7362 else
7363 type = NULL_TREE;
7364 if (type && TYPE_MODE (type) == mode)
7365 TREE_TYPE (ddecl) = type;
7366 else
7367 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7368 DECL_MODE (ddecl) = mode;
7369 dval = gen_rtx_DEBUG_EXPR (mode);
7370 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7371 SET_DECL_RTL (ddecl, dval);
7372 return dval;
7375 #ifdef ELF_ASCII_ESCAPES
7376 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7378 void
7379 default_elf_asm_output_limited_string (FILE *f, const char *s)
7381 int escape;
7382 unsigned char c;
7384 fputs (STRING_ASM_OP, f);
7385 putc ('"', f);
7386 while (*s != '\0')
7388 c = *s;
7389 escape = ELF_ASCII_ESCAPES[c];
7390 switch (escape)
7392 case 0:
7393 putc (c, f);
7394 break;
7395 case 1:
7396 /* TODO: Print in hex with fast function, important for -flto. */
7397 fprintf (f, "\\%03o", c);
7398 break;
7399 default:
7400 putc ('\\', f);
7401 putc (escape, f);
7402 break;
7404 s++;
7406 putc ('\"', f);
7407 putc ('\n', f);
7410 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7412 void
7413 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7415 const char *limit = s + len;
7416 const char *last_null = NULL;
7417 unsigned bytes_in_chunk = 0;
7418 unsigned char c;
7419 int escape;
7421 for (; s < limit; s++)
7423 const char *p;
7425 if (bytes_in_chunk >= 60)
7427 putc ('\"', f);
7428 putc ('\n', f);
7429 bytes_in_chunk = 0;
7432 if (s > last_null)
7434 for (p = s; p < limit && *p != '\0'; p++)
7435 continue;
7436 last_null = p;
7438 else
7439 p = last_null;
7441 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7443 if (bytes_in_chunk > 0)
7445 putc ('\"', f);
7446 putc ('\n', f);
7447 bytes_in_chunk = 0;
7450 default_elf_asm_output_limited_string (f, s);
7451 s = p;
7453 else
7455 if (bytes_in_chunk == 0)
7456 fputs (ASCII_DATA_ASM_OP "\"", f);
7458 c = *s;
7459 escape = ELF_ASCII_ESCAPES[c];
7460 switch (escape)
7462 case 0:
7463 putc (c, f);
7464 bytes_in_chunk++;
7465 break;
7466 case 1:
7467 /* TODO: Print in hex with fast function, important for -flto. */
7468 fprintf (f, "\\%03o", c);
7469 bytes_in_chunk += 4;
7470 break;
7471 default:
7472 putc ('\\', f);
7473 putc (escape, f);
7474 bytes_in_chunk += 2;
7475 break;
7481 if (bytes_in_chunk > 0)
7483 putc ('\"', f);
7484 putc ('\n', f);
7487 #endif
7489 static GTY(()) section *elf_init_array_section;
7490 static GTY(()) section *elf_fini_array_section;
7492 static section *
7493 get_elf_initfini_array_priority_section (int priority,
7494 bool constructor_p)
7496 section *sec;
7497 if (priority != DEFAULT_INIT_PRIORITY)
7499 char buf[18];
7500 sprintf (buf, "%s.%.5u",
7501 constructor_p ? ".init_array" : ".fini_array",
7502 priority);
7503 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7505 else
7507 if (constructor_p)
7509 if (elf_init_array_section == NULL)
7510 elf_init_array_section
7511 = get_section (".init_array",
7512 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7513 sec = elf_init_array_section;
7515 else
7517 if (elf_fini_array_section == NULL)
7518 elf_fini_array_section
7519 = get_section (".fini_array",
7520 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7521 sec = elf_fini_array_section;
7524 return sec;
7527 /* Use .init_array section for constructors. */
7529 void
7530 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7532 section *sec = get_elf_initfini_array_priority_section (priority,
7533 true);
7534 assemble_addr_to_section (symbol, sec);
7537 /* Use .fini_array section for destructors. */
7539 void
7540 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7542 section *sec = get_elf_initfini_array_priority_section (priority,
7543 false);
7544 assemble_addr_to_section (symbol, sec);
7547 /* Default TARGET_ASM_OUTPUT_IDENT hook.
7549 This is a bit of a cheat. The real default is a no-op, but this
7550 hook is the default for all targets with a .ident directive. */
7552 void
7553 default_asm_output_ident_directive (const char *ident_str)
7555 const char *ident_asm_op = "\t.ident\t";
7557 /* If we are still in the front end, do not write out the string
7558 to asm_out_file. Instead, add a fake top-level asm statement.
7559 This allows the front ends to use this hook without actually
7560 writing to asm_out_file, to handle #ident or Pragma Ident. */
7561 if (cgraph_state == CGRAPH_STATE_PARSING)
7563 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
7564 add_asm_node (build_string (strlen (buf), buf));
7566 else
7567 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
7570 #include "gt-varasm.h"