New vectorizer messages; message format change.
[official-gcc.git] / gcc / varasm.c
blob69ec26a5e6b4f643b4330f6db2ac47658cd3f2e0
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 /* The following bit of code ensures that vtable_map
2111 variables are not only in the comdat section, but that
2112 each variable has its own unique comdat name. If this
2113 code is removed, the variables end up in the same section
2114 with a single comdat name.
2116 FIXME: resolve_unique_section needs to deal better with
2117 decls with both DECL_SECTION_NAME and DECL_ONE_ONLY. Once
2118 that is fixed, this if-else statement can be replaced with
2119 a single call to "switch_to_section (sect)". */
2120 if (sect->named.name
2121 && (strcmp (sect->named.name, ".vtable_map_vars") == 0))
2123 #if defined (OBJECT_FORMAT_ELF)
2124 targetm.asm_out.named_section (sect->named.name,
2125 sect->named.common.flags
2126 | SECTION_LINKONCE,
2127 DECL_NAME (decl));
2128 in_section = sect;
2129 #else
2130 switch_to_section (sect);
2131 #endif
2133 else
2134 switch_to_section (sect);
2135 if (align > BITS_PER_UNIT)
2136 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2137 assemble_variable_contents (decl, name, dont_output_data);
2138 if (asan_protected)
2140 unsigned HOST_WIDE_INT int size
2141 = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
2142 assemble_zeros (asan_red_zone_size (size));
2148 /* Given a function declaration (FN_DECL), this function assembles the
2149 function into the .preinit_array section. */
2151 void
2152 assemble_vtv_preinit_initializer (tree fn_decl)
2154 section *sect;
2155 unsigned flags = SECTION_WRITE;
2156 rtx symbol = XEXP (DECL_RTL (fn_decl), 0);
2158 flags |= SECTION_NOTYPE;
2159 sect = get_section (".preinit_array", flags, fn_decl);
2160 switch_to_section (sect);
2161 assemble_addr_to_section (symbol, sect);
2164 /* Return 1 if type TYPE contains any pointers. */
2166 static int
2167 contains_pointers_p (tree type)
2169 switch (TREE_CODE (type))
2171 case POINTER_TYPE:
2172 case REFERENCE_TYPE:
2173 /* I'm not sure whether OFFSET_TYPE needs this treatment,
2174 so I'll play safe and return 1. */
2175 case OFFSET_TYPE:
2176 return 1;
2178 case RECORD_TYPE:
2179 case UNION_TYPE:
2180 case QUAL_UNION_TYPE:
2182 tree fields;
2183 /* For a type that has fields, see if the fields have pointers. */
2184 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2185 if (TREE_CODE (fields) == FIELD_DECL
2186 && contains_pointers_p (TREE_TYPE (fields)))
2187 return 1;
2188 return 0;
2191 case ARRAY_TYPE:
2192 /* An array type contains pointers if its element type does. */
2193 return contains_pointers_p (TREE_TYPE (type));
2195 default:
2196 return 0;
2200 /* We delay assemble_external processing until
2201 the compilation unit is finalized. This is the best we can do for
2202 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2203 it all the way to final. See PR 17982 for further discussion. */
2204 static GTY(()) tree pending_assemble_externals;
2206 #ifdef ASM_OUTPUT_EXTERNAL
2207 /* Some targets delay some output to final using TARGET_ASM_FILE_END.
2208 As a result, assemble_external can be called after the list of externals
2209 is processed and the pointer set destroyed. */
2210 static bool pending_assemble_externals_processed;
2212 /* Avoid O(external_decls**2) lookups in the pending_assemble_externals
2213 TREE_LIST in assemble_external. */
2214 static struct pointer_set_t *pending_assemble_externals_set;
2216 /* True if DECL is a function decl for which no out-of-line copy exists.
2217 It is assumed that DECL's assembler name has been set. */
2219 static bool
2220 incorporeal_function_p (tree decl)
2222 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
2224 const char *name;
2226 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2227 && (DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA
2228 || DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA_WITH_ALIGN))
2229 return true;
2231 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2232 /* Atomic or sync builtins which have survived this far will be
2233 resolved externally and therefore are not incorporeal. */
2234 if (strncmp (name, "__builtin_", 10) == 0)
2235 return true;
2237 return false;
2240 /* Actually do the tests to determine if this is necessary, and invoke
2241 ASM_OUTPUT_EXTERNAL. */
2242 static void
2243 assemble_external_real (tree decl)
2245 rtx rtl = DECL_RTL (decl);
2247 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2248 && !SYMBOL_REF_USED (XEXP (rtl, 0))
2249 && !incorporeal_function_p (decl))
2251 /* Some systems do require some output. */
2252 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2253 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2256 #endif
2258 void
2259 process_pending_assemble_externals (void)
2261 #ifdef ASM_OUTPUT_EXTERNAL
2262 tree list;
2263 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2264 assemble_external_real (TREE_VALUE (list));
2266 pending_assemble_externals = 0;
2267 pending_assemble_externals_processed = true;
2268 pointer_set_destroy (pending_assemble_externals_set);
2269 #endif
2272 /* This TREE_LIST contains any weak symbol declarations waiting
2273 to be emitted. */
2274 static GTY(()) tree weak_decls;
2276 /* Output something to declare an external symbol to the assembler,
2277 and qualifiers such as weakness. (Most assemblers don't need
2278 extern declaration, so we normally output nothing.) Do nothing if
2279 DECL is not external. */
2281 void
2282 assemble_external (tree decl ATTRIBUTE_UNUSED)
2284 /* Make sure that the ASM_OUT_FILE is open.
2285 If it's not, we should not be calling this function. */
2286 gcc_assert (asm_out_file);
2288 /* In a perfect world, the following condition would be true.
2289 Sadly, the Java and Go front ends emit assembly *from the front end*,
2290 bypassing the call graph. See PR52739. Fix before GCC 4.8. */
2291 #if 0
2292 /* This function should only be called if we are expanding, or have
2293 expanded, to RTL.
2294 Ideally, only final.c would be calling this function, but it is
2295 not clear whether that would break things somehow. See PR 17982
2296 for further discussion. */
2297 gcc_assert (cgraph_state == CGRAPH_STATE_EXPANSION
2298 || cgraph_state == CGRAPH_STATE_FINISHED);
2299 #endif
2301 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2302 return;
2304 /* We want to output annotation for weak and external symbols at
2305 very last to check if they are references or not. */
2307 if (TARGET_SUPPORTS_WEAK
2308 && DECL_WEAK (decl)
2309 /* TREE_STATIC is a weird and abused creature which is not
2310 generally the right test for whether an entity has been
2311 locally emitted, inlined or otherwise not-really-extern, but
2312 for declarations that can be weak, it happens to be
2313 match. */
2314 && !TREE_STATIC (decl)
2315 && lookup_attribute ("weak", DECL_ATTRIBUTES (decl))
2316 && value_member (decl, weak_decls) == NULL_TREE)
2317 weak_decls = tree_cons (NULL, decl, weak_decls);
2319 #ifdef ASM_OUTPUT_EXTERNAL
2320 if (pending_assemble_externals_processed)
2322 assemble_external_real (decl);
2323 return;
2326 if (! pointer_set_insert (pending_assemble_externals_set, decl))
2327 pending_assemble_externals = tree_cons (NULL, decl,
2328 pending_assemble_externals);
2329 #endif
2332 /* Similar, for calling a library function FUN. */
2334 void
2335 assemble_external_libcall (rtx fun)
2337 /* Declare library function name external when first used, if nec. */
2338 if (! SYMBOL_REF_USED (fun))
2340 SYMBOL_REF_USED (fun) = 1;
2341 targetm.asm_out.external_libcall (fun);
2345 /* Assemble a label named NAME. */
2347 void
2348 assemble_label (FILE *file, const char *name)
2350 ASM_OUTPUT_LABEL (file, name);
2353 /* Set the symbol_referenced flag for ID. */
2354 void
2355 mark_referenced (tree id)
2357 TREE_SYMBOL_REFERENCED (id) = 1;
2360 /* Set the symbol_referenced flag for DECL and notify callgraph. */
2361 void
2362 mark_decl_referenced (tree decl)
2364 if (TREE_CODE (decl) == FUNCTION_DECL)
2366 /* Extern inline functions don't become needed when referenced.
2367 If we know a method will be emitted in other TU and no new
2368 functions can be marked reachable, just use the external
2369 definition. */
2370 struct cgraph_node *node = cgraph_get_create_node (decl);
2371 if (!DECL_EXTERNAL (decl)
2372 && !node->symbol.definition)
2373 cgraph_mark_force_output_node (node);
2375 else if (TREE_CODE (decl) == VAR_DECL)
2377 struct varpool_node *node = varpool_node_for_decl (decl);
2378 /* C++ frontend use mark_decl_references to force COMDAT variables
2379 to be output that might appear dead otherwise. */
2380 node->symbol.force_output = true;
2382 /* else do nothing - we can get various sorts of CST nodes here,
2383 which do not need to be marked. */
2387 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS
2388 until we find an identifier that is not itself a transparent alias.
2389 Modify the alias passed to it by reference (and all aliases on the
2390 way to the ultimate target), such that they do not have to be
2391 followed again, and return the ultimate target of the alias
2392 chain. */
2394 static inline tree
2395 ultimate_transparent_alias_target (tree *alias)
2397 tree target = *alias;
2399 if (IDENTIFIER_TRANSPARENT_ALIAS (target))
2401 gcc_assert (TREE_CHAIN (target));
2402 target = ultimate_transparent_alias_target (&TREE_CHAIN (target));
2403 gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target)
2404 && ! TREE_CHAIN (target));
2405 *alias = target;
2408 return target;
2411 /* Output to FILE (an assembly file) a reference to NAME. If NAME
2412 starts with a *, the rest of NAME is output verbatim. Otherwise
2413 NAME is transformed in a target-specific way (usually by the
2414 addition of an underscore). */
2416 void
2417 assemble_name_raw (FILE *file, const char *name)
2419 if (name[0] == '*')
2420 fputs (&name[1], file);
2421 else
2422 ASM_OUTPUT_LABELREF (file, name);
2425 /* Like assemble_name_raw, but should be used when NAME might refer to
2426 an entity that is also represented as a tree (like a function or
2427 variable). If NAME does refer to such an entity, that entity will
2428 be marked as referenced. */
2430 void
2431 assemble_name (FILE *file, const char *name)
2433 const char *real_name;
2434 tree id;
2436 real_name = targetm.strip_name_encoding (name);
2438 id = maybe_get_identifier (real_name);
2439 if (id)
2441 tree id_orig = id;
2443 mark_referenced (id);
2444 ultimate_transparent_alias_target (&id);
2445 if (id != id_orig)
2446 name = IDENTIFIER_POINTER (id);
2447 gcc_assert (! TREE_CHAIN (id));
2450 assemble_name_raw (file, name);
2453 /* Allocate SIZE bytes writable static space with a gensym name
2454 and return an RTX to refer to its address. */
2457 assemble_static_space (unsigned HOST_WIDE_INT size)
2459 char name[12];
2460 const char *namestring;
2461 rtx x;
2463 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2464 ++const_labelno;
2465 namestring = ggc_strdup (name);
2467 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2468 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2470 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2471 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2472 BIGGEST_ALIGNMENT);
2473 #else
2474 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2475 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2476 #else
2478 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2479 so that each uninitialized object starts on such a boundary. */
2480 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2481 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2482 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2483 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2484 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2485 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2487 #endif
2488 #endif
2489 return x;
2492 /* Assemble the static constant template for function entry trampolines.
2493 This is done at most once per compilation.
2494 Returns an RTX for the address of the template. */
2496 static GTY(()) rtx initial_trampoline;
2499 assemble_trampoline_template (void)
2501 char label[256];
2502 const char *name;
2503 int align;
2504 rtx symbol;
2506 gcc_assert (targetm.asm_out.trampoline_template != NULL);
2508 if (initial_trampoline)
2509 return initial_trampoline;
2511 /* By default, put trampoline templates in read-only data section. */
2513 #ifdef TRAMPOLINE_SECTION
2514 switch_to_section (TRAMPOLINE_SECTION);
2515 #else
2516 switch_to_section (readonly_data_section);
2517 #endif
2519 /* Write the assembler code to define one. */
2520 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2521 if (align > 0)
2522 ASM_OUTPUT_ALIGN (asm_out_file, align);
2524 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2525 targetm.asm_out.trampoline_template (asm_out_file);
2527 /* Record the rtl to refer to it. */
2528 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2529 name = ggc_strdup (label);
2530 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2531 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2533 initial_trampoline = gen_const_mem (BLKmode, symbol);
2534 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2535 set_mem_size (initial_trampoline, TRAMPOLINE_SIZE);
2537 return initial_trampoline;
2540 /* A and B are either alignments or offsets. Return the minimum alignment
2541 that may be assumed after adding the two together. */
2543 static inline unsigned
2544 min_align (unsigned int a, unsigned int b)
2546 return (a | b) & -(a | b);
2549 /* Return the assembler directive for creating a given kind of integer
2550 object. SIZE is the number of bytes in the object and ALIGNED_P
2551 indicates whether it is known to be aligned. Return NULL if the
2552 assembly dialect has no such directive.
2554 The returned string should be printed at the start of a new line and
2555 be followed immediately by the object's initial value. */
2557 const char *
2558 integer_asm_op (int size, int aligned_p)
2560 struct asm_int_op *ops;
2562 if (aligned_p)
2563 ops = &targetm.asm_out.aligned_op;
2564 else
2565 ops = &targetm.asm_out.unaligned_op;
2567 switch (size)
2569 case 1:
2570 return targetm.asm_out.byte_op;
2571 case 2:
2572 return ops->hi;
2573 case 4:
2574 return ops->si;
2575 case 8:
2576 return ops->di;
2577 case 16:
2578 return ops->ti;
2579 default:
2580 return NULL;
2584 /* Use directive OP to assemble an integer object X. Print OP at the
2585 start of the line, followed immediately by the value of X. */
2587 void
2588 assemble_integer_with_op (const char *op, rtx x)
2590 fputs (op, asm_out_file);
2591 output_addr_const (asm_out_file, x);
2592 fputc ('\n', asm_out_file);
2595 /* The default implementation of the asm_out.integer target hook. */
2597 bool
2598 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2599 unsigned int size ATTRIBUTE_UNUSED,
2600 int aligned_p ATTRIBUTE_UNUSED)
2602 const char *op = integer_asm_op (size, aligned_p);
2603 /* Avoid GAS bugs for large values. Specifically negative values whose
2604 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2605 if (size > UNITS_PER_WORD && size > POINTER_SIZE / BITS_PER_UNIT)
2606 return false;
2607 return op && (assemble_integer_with_op (op, x), true);
2610 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2611 the alignment of the integer in bits. Return 1 if we were able to output
2612 the constant, otherwise 0. We must be able to output the constant,
2613 if FORCE is nonzero. */
2615 bool
2616 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2618 int aligned_p;
2620 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2622 /* See if the target hook can handle this kind of object. */
2623 if (targetm.asm_out.integer (x, size, aligned_p))
2624 return true;
2626 /* If the object is a multi-byte one, try splitting it up. Split
2627 it into words it if is multi-word, otherwise split it into bytes. */
2628 if (size > 1)
2630 enum machine_mode omode, imode;
2631 unsigned int subalign;
2632 unsigned int subsize, i;
2633 enum mode_class mclass;
2635 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2636 subalign = MIN (align, subsize * BITS_PER_UNIT);
2637 if (GET_CODE (x) == CONST_FIXED)
2638 mclass = GET_MODE_CLASS (GET_MODE (x));
2639 else
2640 mclass = MODE_INT;
2642 omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0);
2643 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0);
2645 for (i = 0; i < size; i += subsize)
2647 rtx partial = simplify_subreg (omode, x, imode, i);
2648 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2649 break;
2651 if (i == size)
2652 return true;
2654 /* If we've printed some of it, but not all of it, there's no going
2655 back now. */
2656 gcc_assert (!i);
2659 gcc_assert (!force);
2661 return false;
2664 void
2665 assemble_real (REAL_VALUE_TYPE d, enum machine_mode mode, unsigned int align)
2667 long data[4] = {0, 0, 0, 0};
2668 int i;
2669 int bitsize, nelts, nunits, units_per;
2671 /* This is hairy. We have a quantity of known size. real_to_target
2672 will put it into an array of *host* longs, 32 bits per element
2673 (even if long is more than 32 bits). We need to determine the
2674 number of array elements that are occupied (nelts) and the number
2675 of *target* min-addressable units that will be occupied in the
2676 object file (nunits). We cannot assume that 32 divides the
2677 mode's bitsize (size * BITS_PER_UNIT) evenly.
2679 size * BITS_PER_UNIT is used here to make sure that padding bits
2680 (which might appear at either end of the value; real_to_target
2681 will include the padding bits in its output array) are included. */
2683 nunits = GET_MODE_SIZE (mode);
2684 bitsize = nunits * BITS_PER_UNIT;
2685 nelts = CEIL (bitsize, 32);
2686 units_per = 32 / BITS_PER_UNIT;
2688 real_to_target (data, &d, mode);
2690 /* Put out the first word with the specified alignment. */
2691 assemble_integer (GEN_INT (data[0]), MIN (nunits, units_per), align, 1);
2692 nunits -= units_per;
2694 /* Subsequent words need only 32-bit alignment. */
2695 align = min_align (align, 32);
2697 for (i = 1; i < nelts; i++)
2699 assemble_integer (GEN_INT (data[i]), MIN (nunits, units_per), align, 1);
2700 nunits -= units_per;
2704 /* Given an expression EXP with a constant value,
2705 reduce it to the sum of an assembler symbol and an integer.
2706 Store them both in the structure *VALUE.
2707 EXP must be reducible. */
2709 struct addr_const {
2710 rtx base;
2711 HOST_WIDE_INT offset;
2714 static void
2715 decode_addr_const (tree exp, struct addr_const *value)
2717 tree target = TREE_OPERAND (exp, 0);
2718 int offset = 0;
2719 rtx x;
2721 while (1)
2723 if (TREE_CODE (target) == COMPONENT_REF
2724 && host_integerp (byte_position (TREE_OPERAND (target, 1)), 0))
2726 offset += int_byte_position (TREE_OPERAND (target, 1));
2727 target = TREE_OPERAND (target, 0);
2729 else if (TREE_CODE (target) == ARRAY_REF
2730 || TREE_CODE (target) == ARRAY_RANGE_REF)
2732 offset += (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (target)), 1)
2733 * tree_low_cst (TREE_OPERAND (target, 1), 0));
2734 target = TREE_OPERAND (target, 0);
2736 else if (TREE_CODE (target) == MEM_REF
2737 && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR)
2739 offset += mem_ref_offset (target).low;
2740 target = TREE_OPERAND (TREE_OPERAND (target, 0), 0);
2742 else if (TREE_CODE (target) == INDIRECT_REF
2743 && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR
2744 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0))
2745 == ADDR_EXPR)
2746 target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0);
2747 else
2748 break;
2751 switch (TREE_CODE (target))
2753 case VAR_DECL:
2754 case FUNCTION_DECL:
2755 x = DECL_RTL (target);
2756 break;
2758 case LABEL_DECL:
2759 x = gen_rtx_MEM (FUNCTION_MODE,
2760 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2761 break;
2763 case REAL_CST:
2764 case FIXED_CST:
2765 case STRING_CST:
2766 case COMPLEX_CST:
2767 case CONSTRUCTOR:
2768 case INTEGER_CST:
2769 x = output_constant_def (target, 1);
2770 break;
2772 default:
2773 gcc_unreachable ();
2776 gcc_assert (MEM_P (x));
2777 x = XEXP (x, 0);
2779 value->base = x;
2780 value->offset = offset;
2784 static GTY((param_is (struct constant_descriptor_tree)))
2785 htab_t const_desc_htab;
2787 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2789 /* Constant pool accessor function. */
2791 htab_t
2792 constant_pool_htab (void)
2794 return const_desc_htab;
2797 /* Compute a hash code for a constant expression. */
2799 static hashval_t
2800 const_desc_hash (const void *ptr)
2802 return ((const struct constant_descriptor_tree *)ptr)->hash;
2805 static hashval_t
2806 const_hash_1 (const tree exp)
2808 const char *p;
2809 hashval_t hi;
2810 int len, i;
2811 enum tree_code code = TREE_CODE (exp);
2813 /* Either set P and LEN to the address and len of something to hash and
2814 exit the switch or return a value. */
2816 switch (code)
2818 case INTEGER_CST:
2819 p = (char *) &TREE_INT_CST (exp);
2820 len = sizeof TREE_INT_CST (exp);
2821 break;
2823 case REAL_CST:
2824 return real_hash (TREE_REAL_CST_PTR (exp));
2826 case FIXED_CST:
2827 return fixed_hash (TREE_FIXED_CST_PTR (exp));
2829 case STRING_CST:
2830 p = TREE_STRING_POINTER (exp);
2831 len = TREE_STRING_LENGTH (exp);
2832 break;
2834 case COMPLEX_CST:
2835 return (const_hash_1 (TREE_REALPART (exp)) * 5
2836 + const_hash_1 (TREE_IMAGPART (exp)));
2838 case VECTOR_CST:
2840 unsigned i;
2842 hi = 7 + VECTOR_CST_NELTS (exp);
2844 for (i = 0; i < VECTOR_CST_NELTS (exp); ++i)
2845 hi = hi * 563 + const_hash_1 (VECTOR_CST_ELT (exp, i));
2847 return hi;
2850 case CONSTRUCTOR:
2852 unsigned HOST_WIDE_INT idx;
2853 tree value;
2855 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2857 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
2858 if (value)
2859 hi = hi * 603 + const_hash_1 (value);
2861 return hi;
2864 case ADDR_EXPR:
2865 case FDESC_EXPR:
2867 struct addr_const value;
2869 decode_addr_const (exp, &value);
2870 switch (GET_CODE (value.base))
2872 case SYMBOL_REF:
2873 /* Don't hash the address of the SYMBOL_REF;
2874 only use the offset and the symbol name. */
2875 hi = value.offset;
2876 p = XSTR (value.base, 0);
2877 for (i = 0; p[i] != 0; i++)
2878 hi = ((hi * 613) + (unsigned) (p[i]));
2879 break;
2881 case LABEL_REF:
2882 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13;
2883 break;
2885 default:
2886 gcc_unreachable ();
2889 return hi;
2891 case PLUS_EXPR:
2892 case POINTER_PLUS_EXPR:
2893 case MINUS_EXPR:
2894 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2895 + const_hash_1 (TREE_OPERAND (exp, 1)));
2897 CASE_CONVERT:
2898 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
2900 default:
2901 /* A language specific constant. Just hash the code. */
2902 return code;
2905 /* Compute hashing function. */
2906 hi = len;
2907 for (i = 0; i < len; i++)
2908 hi = ((hi * 613) + (unsigned) (p[i]));
2910 return hi;
2913 /* Wrapper of compare_constant, for the htab interface. */
2914 static int
2915 const_desc_eq (const void *p1, const void *p2)
2917 const struct constant_descriptor_tree *const c1
2918 = (const struct constant_descriptor_tree *) p1;
2919 const struct constant_descriptor_tree *const c2
2920 = (const struct constant_descriptor_tree *) p2;
2921 if (c1->hash != c2->hash)
2922 return 0;
2923 return compare_constant (c1->value, c2->value);
2926 /* Compare t1 and t2, and return 1 only if they are known to result in
2927 the same bit pattern on output. */
2929 static int
2930 compare_constant (const tree t1, const tree t2)
2932 enum tree_code typecode;
2934 if (t1 == NULL_TREE)
2935 return t2 == NULL_TREE;
2936 if (t2 == NULL_TREE)
2937 return 0;
2939 if (TREE_CODE (t1) != TREE_CODE (t2))
2940 return 0;
2942 switch (TREE_CODE (t1))
2944 case INTEGER_CST:
2945 /* Integer constants are the same only if the same width of type. */
2946 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2947 return 0;
2948 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2949 return 0;
2950 return tree_int_cst_equal (t1, t2);
2952 case REAL_CST:
2953 /* Real constants are the same only if the same width of type. */
2954 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2955 return 0;
2957 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
2959 case FIXED_CST:
2960 /* Fixed constants are the same only if the same width of type. */
2961 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2962 return 0;
2964 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
2966 case STRING_CST:
2967 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2968 return 0;
2970 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
2971 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
2972 TREE_STRING_LENGTH (t1)));
2974 case COMPLEX_CST:
2975 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
2976 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
2978 case VECTOR_CST:
2980 unsigned i;
2982 if (VECTOR_CST_NELTS (t1) != VECTOR_CST_NELTS (t2))
2983 return 0;
2985 for (i = 0; i < VECTOR_CST_NELTS (t1); ++i)
2986 if (!compare_constant (VECTOR_CST_ELT (t1, i),
2987 VECTOR_CST_ELT (t2, i)))
2988 return 0;
2990 return 1;
2993 case CONSTRUCTOR:
2995 vec<constructor_elt, va_gc> *v1, *v2;
2996 unsigned HOST_WIDE_INT idx;
2998 typecode = TREE_CODE (TREE_TYPE (t1));
2999 if (typecode != TREE_CODE (TREE_TYPE (t2)))
3000 return 0;
3002 if (typecode == ARRAY_TYPE)
3004 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
3005 /* For arrays, check that the sizes all match. */
3006 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
3007 || size_1 == -1
3008 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
3009 return 0;
3011 else
3013 /* For record and union constructors, require exact type
3014 equality. */
3015 if (TREE_TYPE (t1) != TREE_TYPE (t2))
3016 return 0;
3019 v1 = CONSTRUCTOR_ELTS (t1);
3020 v2 = CONSTRUCTOR_ELTS (t2);
3021 if (vec_safe_length (v1) != vec_safe_length (v2))
3022 return 0;
3024 for (idx = 0; idx < vec_safe_length (v1); ++idx)
3026 constructor_elt *c1 = &(*v1)[idx];
3027 constructor_elt *c2 = &(*v2)[idx];
3029 /* Check that each value is the same... */
3030 if (!compare_constant (c1->value, c2->value))
3031 return 0;
3032 /* ... and that they apply to the same fields! */
3033 if (typecode == ARRAY_TYPE)
3035 if (!compare_constant (c1->index, c2->index))
3036 return 0;
3038 else
3040 if (c1->index != c2->index)
3041 return 0;
3045 return 1;
3048 case ADDR_EXPR:
3049 case FDESC_EXPR:
3051 struct addr_const value1, value2;
3052 enum rtx_code code;
3053 int ret;
3055 decode_addr_const (t1, &value1);
3056 decode_addr_const (t2, &value2);
3058 if (value1.offset != value2.offset)
3059 return 0;
3061 code = GET_CODE (value1.base);
3062 if (code != GET_CODE (value2.base))
3063 return 0;
3065 switch (code)
3067 case SYMBOL_REF:
3068 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3069 break;
3071 case LABEL_REF:
3072 ret = (CODE_LABEL_NUMBER (XEXP (value1.base, 0))
3073 == CODE_LABEL_NUMBER (XEXP (value2.base, 0)));
3074 break;
3076 default:
3077 gcc_unreachable ();
3079 return ret;
3082 case PLUS_EXPR:
3083 case POINTER_PLUS_EXPR:
3084 case MINUS_EXPR:
3085 case RANGE_EXPR:
3086 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3087 && compare_constant(TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3089 CASE_CONVERT:
3090 case VIEW_CONVERT_EXPR:
3091 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3093 default:
3094 return 0;
3097 gcc_unreachable ();
3100 /* Make a copy of the whole tree structure for a constant. This
3101 handles the same types of nodes that compare_constant handles. */
3103 static tree
3104 copy_constant (tree exp)
3106 switch (TREE_CODE (exp))
3108 case ADDR_EXPR:
3109 /* For ADDR_EXPR, we do not want to copy the decl whose address
3110 is requested. We do want to copy constants though. */
3111 if (CONSTANT_CLASS_P (TREE_OPERAND (exp, 0)))
3112 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
3113 copy_constant (TREE_OPERAND (exp, 0)));
3114 else
3115 return copy_node (exp);
3117 case INTEGER_CST:
3118 case REAL_CST:
3119 case FIXED_CST:
3120 case STRING_CST:
3121 return copy_node (exp);
3123 case COMPLEX_CST:
3124 return build_complex (TREE_TYPE (exp),
3125 copy_constant (TREE_REALPART (exp)),
3126 copy_constant (TREE_IMAGPART (exp)));
3128 case PLUS_EXPR:
3129 case POINTER_PLUS_EXPR:
3130 case MINUS_EXPR:
3131 return build2 (TREE_CODE (exp), TREE_TYPE (exp),
3132 copy_constant (TREE_OPERAND (exp, 0)),
3133 copy_constant (TREE_OPERAND (exp, 1)));
3135 CASE_CONVERT:
3136 case VIEW_CONVERT_EXPR:
3137 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
3138 copy_constant (TREE_OPERAND (exp, 0)));
3140 case VECTOR_CST:
3141 return build_vector (TREE_TYPE (exp), VECTOR_CST_ELTS (exp));
3143 case CONSTRUCTOR:
3145 tree copy = copy_node (exp);
3146 vec<constructor_elt, va_gc> *v;
3147 unsigned HOST_WIDE_INT idx;
3148 tree purpose, value;
3150 vec_alloc (v, vec_safe_length (CONSTRUCTOR_ELTS (exp)));
3151 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (exp), idx, purpose, value)
3153 constructor_elt ce = {purpose, copy_constant (value)};
3154 v->quick_push (ce);
3156 CONSTRUCTOR_ELTS (copy) = v;
3157 return copy;
3160 default:
3161 gcc_unreachable ();
3165 /* Return the section into which constant EXP should be placed. */
3167 static section *
3168 get_constant_section (tree exp, unsigned int align)
3170 return targetm.asm_out.select_section (exp,
3171 compute_reloc_for_constant (exp),
3172 align);
3175 /* Return the size of constant EXP in bytes. */
3177 static HOST_WIDE_INT
3178 get_constant_size (tree exp)
3180 HOST_WIDE_INT size;
3182 size = int_size_in_bytes (TREE_TYPE (exp));
3183 if (TREE_CODE (exp) == STRING_CST)
3184 size = MAX (TREE_STRING_LENGTH (exp), size);
3185 return size;
3188 /* Subroutine of output_constant_def:
3189 No constant equal to EXP is known to have been output.
3190 Make a constant descriptor to enter EXP in the hash table.
3191 Assign the label number and construct RTL to refer to the
3192 constant's location in memory.
3193 Caller is responsible for updating the hash table. */
3195 static struct constant_descriptor_tree *
3196 build_constant_desc (tree exp)
3198 struct constant_descriptor_tree *desc;
3199 rtx symbol, rtl;
3200 char label[256];
3201 int labelno;
3202 tree decl;
3204 desc = ggc_alloc_constant_descriptor_tree ();
3205 desc->value = copy_constant (exp);
3207 /* Propagate marked-ness to copied constant. */
3208 if (flag_mudflap && mf_marked_p (exp))
3209 mf_mark (desc->value);
3211 /* Create a string containing the label name, in LABEL. */
3212 labelno = const_labelno++;
3213 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3215 /* Construct the VAR_DECL associated with the constant. */
3216 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3217 TREE_TYPE (exp));
3218 DECL_ARTIFICIAL (decl) = 1;
3219 DECL_IGNORED_P (decl) = 1;
3220 TREE_READONLY (decl) = 1;
3221 TREE_STATIC (decl) = 1;
3222 TREE_ADDRESSABLE (decl) = 1;
3223 /* We don't set the RTL yet as this would cause varpool to assume that the
3224 variable is referenced. Moreover, it would just be dropped in LTO mode.
3225 Instead we set the flag that will be recognized in make_decl_rtl. */
3226 DECL_IN_CONSTANT_POOL (decl) = 1;
3227 DECL_INITIAL (decl) = desc->value;
3228 /* ??? CONSTANT_ALIGNMENT hasn't been updated for vector types on most
3229 architectures so use DATA_ALIGNMENT as well, except for strings. */
3230 if (TREE_CODE (exp) == STRING_CST)
3232 #ifdef CONSTANT_ALIGNMENT
3233 DECL_ALIGN (decl) = CONSTANT_ALIGNMENT (exp, DECL_ALIGN (decl));
3234 #endif
3236 else
3237 align_variable (decl, 0);
3239 /* Now construct the SYMBOL_REF and the MEM. */
3240 if (use_object_blocks_p ())
3242 section *sect = get_constant_section (exp, DECL_ALIGN (decl));
3243 symbol = create_block_symbol (ggc_strdup (label),
3244 get_block_for_section (sect), -1);
3246 else
3247 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3248 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3249 SET_SYMBOL_REF_DECL (symbol, decl);
3250 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3252 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3253 set_mem_attributes (rtl, exp, 1);
3254 set_mem_alias_set (rtl, 0);
3255 set_mem_alias_set (rtl, const_alias_set);
3257 /* We cannot share RTX'es in pool entries.
3258 Mark this piece of RTL as required for unsharing. */
3259 RTX_FLAG (rtl, used) = 1;
3261 /* Set flags or add text to the name to record information, such as
3262 that it is a local symbol. If the name is changed, the macro
3263 ASM_OUTPUT_LABELREF will have to know how to strip this
3264 information. This call might invalidate our local variable
3265 SYMBOL; we can't use it afterward. */
3266 targetm.encode_section_info (exp, rtl, true);
3268 desc->rtl = rtl;
3270 return desc;
3273 /* Return an rtx representing a reference to constant data in memory
3274 for the constant expression EXP.
3276 If assembler code for such a constant has already been output,
3277 return an rtx to refer to it.
3278 Otherwise, output such a constant in memory
3279 and generate an rtx for it.
3281 If DEFER is nonzero, this constant can be deferred and output only
3282 if referenced in the function after all optimizations.
3284 `const_desc_table' records which constants already have label strings. */
3287 output_constant_def (tree exp, int defer)
3289 struct constant_descriptor_tree *desc;
3290 struct constant_descriptor_tree key;
3291 void **loc;
3293 /* Look up EXP in the table of constant descriptors. If we didn't find
3294 it, create a new one. */
3295 key.value = exp;
3296 key.hash = const_hash_1 (exp);
3297 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3299 desc = (struct constant_descriptor_tree *) *loc;
3300 if (desc == 0)
3302 desc = build_constant_desc (exp);
3303 desc->hash = key.hash;
3304 *loc = desc;
3307 maybe_output_constant_def_contents (desc, defer);
3308 return desc->rtl;
3311 /* Subroutine of output_constant_def: Decide whether or not we need to
3312 output the constant DESC now, and if so, do it. */
3313 static void
3314 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3315 int defer)
3317 rtx symbol = XEXP (desc->rtl, 0);
3318 tree exp = desc->value;
3320 if (flag_syntax_only)
3321 return;
3323 if (TREE_ASM_WRITTEN (exp))
3324 /* Already output; don't do it again. */
3325 return;
3327 /* We can always defer constants as long as the context allows
3328 doing so. */
3329 if (defer)
3331 /* Increment n_deferred_constants if it exists. It needs to be at
3332 least as large as the number of constants actually referred to
3333 by the function. If it's too small we'll stop looking too early
3334 and fail to emit constants; if it's too large we'll only look
3335 through the entire function when we could have stopped earlier. */
3336 if (cfun)
3337 n_deferred_constants++;
3338 return;
3341 output_constant_def_contents (symbol);
3344 /* Subroutine of output_constant_def_contents. Output the definition
3345 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3346 constant's alignment in bits. */
3348 static void
3349 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3351 HOST_WIDE_INT size;
3353 size = get_constant_size (exp);
3355 /* Do any machine/system dependent processing of the constant. */
3356 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3358 /* Output the value of EXP. */
3359 output_constant (exp, size, align);
3362 /* We must output the constant data referred to by SYMBOL; do so. */
3364 static void
3365 output_constant_def_contents (rtx symbol)
3367 tree decl = SYMBOL_REF_DECL (symbol);
3368 tree exp = DECL_INITIAL (decl);
3369 unsigned int align;
3370 bool asan_protected = false;
3372 /* Make sure any other constants whose addresses appear in EXP
3373 are assigned label numbers. */
3374 output_addressed_constants (exp);
3376 /* We are no longer deferring this constant. */
3377 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3379 if (flag_asan && TREE_CODE (exp) == STRING_CST
3380 && asan_protect_global (exp))
3382 asan_protected = true;
3383 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
3384 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
3387 /* If the constant is part of an object block, make sure that the
3388 decl has been positioned within its block, but do not write out
3389 its definition yet. output_object_blocks will do that later. */
3390 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3391 place_block_symbol (symbol);
3392 else
3394 align = DECL_ALIGN (decl);
3395 switch_to_section (get_constant_section (exp, align));
3396 if (align > BITS_PER_UNIT)
3397 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3398 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3399 if (asan_protected)
3401 HOST_WIDE_INT size = get_constant_size (exp);
3402 assemble_zeros (asan_red_zone_size (size));
3405 if (flag_mudflap)
3406 mudflap_enqueue_constant (exp);
3409 /* Look up EXP in the table of constant descriptors. Return the rtl
3410 if it has been emitted, else null. */
3413 lookup_constant_def (tree exp)
3415 struct constant_descriptor_tree *desc;
3416 struct constant_descriptor_tree key;
3418 key.value = exp;
3419 key.hash = const_hash_1 (exp);
3420 desc = (struct constant_descriptor_tree *)
3421 htab_find_with_hash (const_desc_htab, &key, key.hash);
3423 return (desc ? desc->rtl : NULL_RTX);
3426 /* Return a tree representing a reference to constant data in memory
3427 for the constant expression EXP.
3429 This is the counterpart of output_constant_def at the Tree level. */
3431 tree
3432 tree_output_constant_def (tree exp)
3434 struct constant_descriptor_tree *desc, key;
3435 void **loc;
3436 tree decl;
3438 /* Look up EXP in the table of constant descriptors. If we didn't find
3439 it, create a new one. */
3440 key.value = exp;
3441 key.hash = const_hash_1 (exp);
3442 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3444 desc = (struct constant_descriptor_tree *) *loc;
3445 if (desc == 0)
3447 desc = build_constant_desc (exp);
3448 desc->hash = key.hash;
3449 *loc = desc;
3452 decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3453 varpool_finalize_decl (decl);
3454 return decl;
3457 /* Used in the hash tables to avoid outputting the same constant
3458 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3459 are output once per function, not once per file. */
3460 /* ??? Only a few targets need per-function constant pools. Most
3461 can use one per-file pool. Should add a targetm bit to tell the
3462 difference. */
3464 struct GTY(()) rtx_constant_pool {
3465 /* Pointers to first and last constant in pool, as ordered by offset. */
3466 struct constant_descriptor_rtx *first;
3467 struct constant_descriptor_rtx *last;
3469 /* Hash facility for making memory-constants from constant rtl-expressions.
3470 It is used on RISC machines where immediate integer arguments and
3471 constant addresses are restricted so that such constants must be stored
3472 in memory. */
3473 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_htab;
3475 /* Current offset in constant pool (does not include any
3476 machine-specific header). */
3477 HOST_WIDE_INT offset;
3480 struct GTY((chain_next ("%h.next"))) constant_descriptor_rtx {
3481 struct constant_descriptor_rtx *next;
3482 rtx mem;
3483 rtx sym;
3484 rtx constant;
3485 HOST_WIDE_INT offset;
3486 hashval_t hash;
3487 enum machine_mode mode;
3488 unsigned int align;
3489 int labelno;
3490 int mark;
3493 /* Hash and compare functions for const_rtx_htab. */
3495 static hashval_t
3496 const_desc_rtx_hash (const void *ptr)
3498 const struct constant_descriptor_rtx *const desc
3499 = (const struct constant_descriptor_rtx *) ptr;
3500 return desc->hash;
3503 static int
3504 const_desc_rtx_eq (const void *a, const void *b)
3506 const struct constant_descriptor_rtx *const x
3507 = (const struct constant_descriptor_rtx *) a;
3508 const struct constant_descriptor_rtx *const y
3509 = (const struct constant_descriptor_rtx *) b;
3511 if (x->mode != y->mode)
3512 return 0;
3513 return rtx_equal_p (x->constant, y->constant);
3516 /* This is the worker function for const_rtx_hash, called via for_each_rtx. */
3518 static int
3519 const_rtx_hash_1 (rtx *xp, void *data)
3521 unsigned HOST_WIDE_INT hwi;
3522 enum machine_mode mode;
3523 enum rtx_code code;
3524 hashval_t h, *hp;
3525 rtx x;
3527 x = *xp;
3528 code = GET_CODE (x);
3529 mode = GET_MODE (x);
3530 h = (hashval_t) code * 1048573 + mode;
3532 switch (code)
3534 case CONST_INT:
3535 hwi = INTVAL (x);
3536 fold_hwi:
3538 int shift = sizeof (hashval_t) * CHAR_BIT;
3539 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3540 int i;
3542 h ^= (hashval_t) hwi;
3543 for (i = 1; i < n; ++i)
3545 hwi >>= shift;
3546 h ^= (hashval_t) hwi;
3549 break;
3551 case CONST_DOUBLE:
3552 if (mode == VOIDmode)
3554 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3555 goto fold_hwi;
3557 else
3558 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3559 break;
3561 case CONST_FIXED:
3562 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3563 break;
3565 case CONST_VECTOR:
3567 int i;
3568 for (i = XVECLEN (x, 0); i-- > 0; )
3569 h = h * 251 + const_rtx_hash_1 (&XVECEXP (x, 0, i), data);
3571 break;
3573 case SYMBOL_REF:
3574 h ^= htab_hash_string (XSTR (x, 0));
3575 break;
3577 case LABEL_REF:
3578 h = h * 251 + CODE_LABEL_NUMBER (XEXP (x, 0));
3579 break;
3581 case UNSPEC:
3582 case UNSPEC_VOLATILE:
3583 h = h * 251 + XINT (x, 1);
3584 break;
3586 default:
3587 break;
3590 hp = (hashval_t *) data;
3591 *hp = *hp * 509 + h;
3592 return 0;
3595 /* Compute a hash value for X, which should be a constant. */
3597 static hashval_t
3598 const_rtx_hash (rtx x)
3600 hashval_t h = 0;
3601 for_each_rtx (&x, const_rtx_hash_1, &h);
3602 return h;
3606 /* Create and return a new rtx constant pool. */
3608 static struct rtx_constant_pool *
3609 create_constant_pool (void)
3611 struct rtx_constant_pool *pool;
3613 pool = ggc_alloc_rtx_constant_pool ();
3614 pool->const_rtx_htab = htab_create_ggc (31, const_desc_rtx_hash,
3615 const_desc_rtx_eq, NULL);
3616 pool->first = NULL;
3617 pool->last = NULL;
3618 pool->offset = 0;
3619 return pool;
3622 /* Initialize constant pool hashing for a new function. */
3624 void
3625 init_varasm_status (void)
3627 crtl->varasm.pool = create_constant_pool ();
3628 crtl->varasm.deferred_constants = 0;
3631 /* Given a MINUS expression, simplify it if both sides
3632 include the same symbol. */
3635 simplify_subtraction (rtx x)
3637 rtx r = simplify_rtx (x);
3638 return r ? r : x;
3641 /* Given a constant rtx X, make (or find) a memory constant for its value
3642 and return a MEM rtx to refer to it in memory. */
3645 force_const_mem (enum machine_mode mode, rtx x)
3647 struct constant_descriptor_rtx *desc, tmp;
3648 struct rtx_constant_pool *pool;
3649 char label[256];
3650 rtx def, symbol;
3651 hashval_t hash;
3652 unsigned int align;
3653 void **slot;
3655 /* If we're not allowed to drop X into the constant pool, don't. */
3656 if (targetm.cannot_force_const_mem (mode, x))
3657 return NULL_RTX;
3659 /* Record that this function has used a constant pool entry. */
3660 crtl->uses_const_pool = 1;
3662 /* Decide which pool to use. */
3663 pool = (targetm.use_blocks_for_constant_p (mode, x)
3664 ? shared_constant_pool
3665 : crtl->varasm.pool);
3667 /* Lookup the value in the hashtable. */
3668 tmp.constant = x;
3669 tmp.mode = mode;
3670 hash = const_rtx_hash (x);
3671 slot = htab_find_slot_with_hash (pool->const_rtx_htab, &tmp, hash, INSERT);
3672 desc = (struct constant_descriptor_rtx *) *slot;
3674 /* If the constant was already present, return its memory. */
3675 if (desc)
3676 return copy_rtx (desc->mem);
3678 /* Otherwise, create a new descriptor. */
3679 desc = ggc_alloc_constant_descriptor_rtx ();
3680 *slot = desc;
3682 /* Align the location counter as required by EXP's data type. */
3683 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3684 #ifdef CONSTANT_ALIGNMENT
3686 tree type = lang_hooks.types.type_for_mode (mode, 0);
3687 if (type != NULL_TREE)
3688 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3690 #endif
3692 pool->offset += (align / BITS_PER_UNIT) - 1;
3693 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3695 desc->next = NULL;
3696 desc->constant = copy_rtx (tmp.constant);
3697 desc->offset = pool->offset;
3698 desc->hash = hash;
3699 desc->mode = mode;
3700 desc->align = align;
3701 desc->labelno = const_labelno;
3702 desc->mark = 0;
3704 pool->offset += GET_MODE_SIZE (mode);
3705 if (pool->last)
3706 pool->last->next = desc;
3707 else
3708 pool->first = pool->last = desc;
3709 pool->last = desc;
3711 /* Create a string containing the label name, in LABEL. */
3712 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3713 ++const_labelno;
3715 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3716 the constants pool. */
3717 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3719 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3720 symbol = create_block_symbol (ggc_strdup (label),
3721 get_block_for_section (sect), -1);
3723 else
3724 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3725 desc->sym = symbol;
3726 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3727 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3728 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3730 /* Construct the MEM. */
3731 desc->mem = def = gen_const_mem (mode, symbol);
3732 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3733 set_mem_align (def, align);
3735 /* If we're dropping a label to the constant pool, make sure we
3736 don't delete it. */
3737 if (GET_CODE (x) == LABEL_REF)
3738 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3740 return copy_rtx (def);
3743 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3746 get_pool_constant (rtx addr)
3748 return SYMBOL_REF_CONSTANT (addr)->constant;
3751 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3752 and whether it has been output or not. */
3755 get_pool_constant_mark (rtx addr, bool *pmarked)
3757 struct constant_descriptor_rtx *desc;
3759 desc = SYMBOL_REF_CONSTANT (addr);
3760 *pmarked = (desc->mark != 0);
3761 return desc->constant;
3764 /* Similar, return the mode. */
3766 enum machine_mode
3767 get_pool_mode (const_rtx addr)
3769 return SYMBOL_REF_CONSTANT (addr)->mode;
3772 /* Return the size of the constant pool. */
3775 get_pool_size (void)
3777 return crtl->varasm.pool->offset;
3780 /* Worker function for output_constant_pool_1. Emit assembly for X
3781 in MODE with known alignment ALIGN. */
3783 static void
3784 output_constant_pool_2 (enum machine_mode mode, rtx x, unsigned int align)
3786 switch (GET_MODE_CLASS (mode))
3788 case MODE_FLOAT:
3789 case MODE_DECIMAL_FLOAT:
3791 REAL_VALUE_TYPE r;
3793 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3794 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3795 assemble_real (r, mode, align);
3796 break;
3799 case MODE_INT:
3800 case MODE_PARTIAL_INT:
3801 case MODE_FRACT:
3802 case MODE_UFRACT:
3803 case MODE_ACCUM:
3804 case MODE_UACCUM:
3805 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3806 break;
3808 case MODE_VECTOR_FLOAT:
3809 case MODE_VECTOR_INT:
3810 case MODE_VECTOR_FRACT:
3811 case MODE_VECTOR_UFRACT:
3812 case MODE_VECTOR_ACCUM:
3813 case MODE_VECTOR_UACCUM:
3815 int i, units;
3816 enum machine_mode submode = GET_MODE_INNER (mode);
3817 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3819 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3820 units = CONST_VECTOR_NUNITS (x);
3822 for (i = 0; i < units; i++)
3824 rtx elt = CONST_VECTOR_ELT (x, i);
3825 output_constant_pool_2 (submode, elt, i ? subalign : align);
3828 break;
3830 default:
3831 gcc_unreachable ();
3835 /* Worker function for output_constant_pool. Emit constant DESC,
3836 giving it ALIGN bits of alignment. */
3838 static void
3839 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3840 unsigned int align)
3842 rtx x, tmp;
3844 x = desc->constant;
3846 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3847 whose CODE_LABEL has been deleted. This can occur if a jump table
3848 is eliminated by optimization. If so, write a constant of zero
3849 instead. Note that this can also happen by turning the
3850 CODE_LABEL into a NOTE. */
3851 /* ??? This seems completely and utterly wrong. Certainly it's
3852 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3853 functioning even with INSN_DELETED_P and friends. */
3855 tmp = x;
3856 switch (GET_CODE (tmp))
3858 case CONST:
3859 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3860 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
3861 break;
3862 tmp = XEXP (XEXP (tmp, 0), 0);
3863 /* FALLTHRU */
3865 case LABEL_REF:
3866 tmp = XEXP (tmp, 0);
3867 gcc_assert (!INSN_DELETED_P (tmp));
3868 gcc_assert (!NOTE_P (tmp)
3869 || NOTE_KIND (tmp) != NOTE_INSN_DELETED);
3870 break;
3872 default:
3873 break;
3876 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3877 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3878 align, desc->labelno, done);
3879 #endif
3881 assemble_align (align);
3883 /* Output the label. */
3884 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3886 /* Output the data. */
3887 output_constant_pool_2 (desc->mode, x, align);
3889 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3890 sections have proper size. */
3891 if (align > GET_MODE_BITSIZE (desc->mode)
3892 && in_section
3893 && (in_section->common.flags & SECTION_MERGE))
3894 assemble_align (align);
3896 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3897 done:
3898 #endif
3899 return;
3902 /* Given a SYMBOL_REF CURRENT_RTX, mark it and all constants it refers
3903 to as used. Emit referenced deferred strings. This function can
3904 be used with for_each_rtx to mark all SYMBOL_REFs in an rtx. */
3906 static int
3907 mark_constant (rtx *current_rtx, void *data ATTRIBUTE_UNUSED)
3909 rtx x = *current_rtx;
3911 if (x == NULL_RTX || GET_CODE (x) != SYMBOL_REF)
3912 return 0;
3914 if (CONSTANT_POOL_ADDRESS_P (x))
3916 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
3917 if (desc->mark == 0)
3919 desc->mark = 1;
3920 for_each_rtx (&desc->constant, mark_constant, NULL);
3923 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3925 tree decl = SYMBOL_REF_DECL (x);
3926 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
3928 n_deferred_constants--;
3929 output_constant_def_contents (x);
3933 return -1;
3936 /* Look through appropriate parts of INSN, marking all entries in the
3937 constant pool which are actually being used. Entries that are only
3938 referenced by other constants are also marked as used. Emit
3939 deferred strings that are used. */
3941 static void
3942 mark_constants (rtx insn)
3944 if (!INSN_P (insn))
3945 return;
3947 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3948 insns, not any notes that may be attached. We don't want to mark
3949 a constant just because it happens to appear in a REG_EQUIV note. */
3950 if (GET_CODE (PATTERN (insn)) == SEQUENCE)
3952 rtx seq = PATTERN (insn);
3953 int i, n = XVECLEN (seq, 0);
3954 for (i = 0; i < n; ++i)
3956 rtx subinsn = XVECEXP (seq, 0, i);
3957 if (INSN_P (subinsn))
3958 for_each_rtx (&PATTERN (subinsn), mark_constant, NULL);
3961 else
3962 for_each_rtx (&PATTERN (insn), mark_constant, NULL);
3965 /* Look through the instructions for this function, and mark all the
3966 entries in POOL which are actually being used. Emit deferred constants
3967 which have indeed been used. */
3969 static void
3970 mark_constant_pool (void)
3972 rtx insn;
3974 if (!crtl->uses_const_pool && n_deferred_constants == 0)
3975 return;
3977 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3978 mark_constants (insn);
3981 /* Write all the constants in POOL. */
3983 static void
3984 output_constant_pool_contents (struct rtx_constant_pool *pool)
3986 struct constant_descriptor_rtx *desc;
3988 for (desc = pool->first; desc ; desc = desc->next)
3989 if (desc->mark)
3991 /* If the constant is part of an object_block, make sure that
3992 the constant has been positioned within its block, but do not
3993 write out its definition yet. output_object_blocks will do
3994 that later. */
3995 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
3996 && SYMBOL_REF_BLOCK (desc->sym))
3997 place_block_symbol (desc->sym);
3998 else
4000 switch_to_section (targetm.asm_out.select_rtx_section
4001 (desc->mode, desc->constant, desc->align));
4002 output_constant_pool_1 (desc, desc->align);
4007 /* Mark all constants that are used in the current function, then write
4008 out the function's private constant pool. */
4010 static void
4011 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
4012 tree fndecl ATTRIBUTE_UNUSED)
4014 struct rtx_constant_pool *pool = crtl->varasm.pool;
4016 /* It is possible for gcc to call force_const_mem and then to later
4017 discard the instructions which refer to the constant. In such a
4018 case we do not need to output the constant. */
4019 mark_constant_pool ();
4021 #ifdef ASM_OUTPUT_POOL_PROLOGUE
4022 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
4023 #endif
4025 output_constant_pool_contents (pool);
4027 #ifdef ASM_OUTPUT_POOL_EPILOGUE
4028 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
4029 #endif
4032 /* Write the contents of the shared constant pool. */
4034 void
4035 output_shared_constant_pool (void)
4037 output_constant_pool_contents (shared_constant_pool);
4040 /* Determine what kind of relocations EXP may need. */
4043 compute_reloc_for_constant (tree exp)
4045 int reloc = 0, reloc2;
4046 tree tem;
4048 switch (TREE_CODE (exp))
4050 case ADDR_EXPR:
4051 case FDESC_EXPR:
4052 /* Go inside any operations that get_inner_reference can handle and see
4053 if what's inside is a constant: no need to do anything here for
4054 addresses of variables or functions. */
4055 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4056 tem = TREE_OPERAND (tem, 0))
4059 if (TREE_CODE (tem) == MEM_REF
4060 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4062 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4063 break;
4066 if (TREE_PUBLIC (tem))
4067 reloc |= 2;
4068 else
4069 reloc |= 1;
4070 break;
4072 case PLUS_EXPR:
4073 case POINTER_PLUS_EXPR:
4074 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4075 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4076 break;
4078 case MINUS_EXPR:
4079 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4080 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4081 /* The difference of two local labels is computable at link time. */
4082 if (reloc == 1 && reloc2 == 1)
4083 reloc = 0;
4084 else
4085 reloc |= reloc2;
4086 break;
4088 CASE_CONVERT:
4089 case VIEW_CONVERT_EXPR:
4090 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4091 break;
4093 case CONSTRUCTOR:
4095 unsigned HOST_WIDE_INT idx;
4096 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4097 if (tem != 0)
4098 reloc |= compute_reloc_for_constant (tem);
4100 break;
4102 default:
4103 break;
4105 return reloc;
4108 /* Find all the constants whose addresses are referenced inside of EXP,
4109 and make sure assembler code with a label has been output for each one.
4110 Indicate whether an ADDR_EXPR has been encountered. */
4112 static void
4113 output_addressed_constants (tree exp)
4115 tree tem;
4117 switch (TREE_CODE (exp))
4119 case ADDR_EXPR:
4120 case FDESC_EXPR:
4121 /* Go inside any operations that get_inner_reference can handle and see
4122 if what's inside is a constant: no need to do anything here for
4123 addresses of variables or functions. */
4124 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4125 tem = TREE_OPERAND (tem, 0))
4128 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4129 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4130 tem = DECL_INITIAL (tem);
4132 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4133 output_constant_def (tem, 0);
4135 if (TREE_CODE (tem) == MEM_REF)
4136 output_addressed_constants (TREE_OPERAND (tem, 0));
4137 break;
4139 case PLUS_EXPR:
4140 case POINTER_PLUS_EXPR:
4141 case MINUS_EXPR:
4142 output_addressed_constants (TREE_OPERAND (exp, 1));
4143 /* Fall through. */
4145 CASE_CONVERT:
4146 case VIEW_CONVERT_EXPR:
4147 output_addressed_constants (TREE_OPERAND (exp, 0));
4148 break;
4150 case CONSTRUCTOR:
4152 unsigned HOST_WIDE_INT idx;
4153 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4154 if (tem != 0)
4155 output_addressed_constants (tem);
4157 break;
4159 default:
4160 break;
4164 /* Whether a constructor CTOR is a valid static constant initializer if all
4165 its elements are. This used to be internal to initializer_constant_valid_p
4166 and has been exposed to let other functions like categorize_ctor_elements
4167 evaluate the property while walking a constructor for other purposes. */
4169 bool
4170 constructor_static_from_elts_p (const_tree ctor)
4172 return (TREE_CONSTANT (ctor)
4173 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4174 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4175 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4178 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4179 tree *cache);
4181 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4182 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4183 which are valid when ENDTYPE is an integer of any size; in
4184 particular, this does not accept a pointer minus a constant. This
4185 returns null_pointer_node if the VALUE is an absolute constant
4186 which can be used to initialize a static variable. Otherwise it
4187 returns NULL. */
4189 static tree
4190 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4192 tree op0, op1;
4194 if (!INTEGRAL_TYPE_P (endtype))
4195 return NULL_TREE;
4197 op0 = TREE_OPERAND (value, 0);
4198 op1 = TREE_OPERAND (value, 1);
4200 /* Like STRIP_NOPS except allow the operand mode to widen. This
4201 works around a feature of fold that simplifies (int)(p1 - p2) to
4202 ((int)p1 - (int)p2) under the theory that the narrower operation
4203 is cheaper. */
4205 while (CONVERT_EXPR_P (op0)
4206 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4208 tree inner = TREE_OPERAND (op0, 0);
4209 if (inner == error_mark_node
4210 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4211 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
4212 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4213 break;
4214 op0 = inner;
4217 while (CONVERT_EXPR_P (op1)
4218 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4220 tree inner = TREE_OPERAND (op1, 0);
4221 if (inner == error_mark_node
4222 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4223 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
4224 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4225 break;
4226 op1 = inner;
4229 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4230 if (!op0)
4231 return NULL_TREE;
4233 op1 = initializer_constant_valid_p_1 (op1, endtype,
4234 cache ? cache + 2 : NULL);
4235 /* Both initializers must be known. */
4236 if (op1)
4238 if (op0 == op1
4239 && (op0 == null_pointer_node
4240 || TREE_CODE (value) == MINUS_EXPR))
4241 return null_pointer_node;
4243 /* Support differences between labels. */
4244 if (TREE_CODE (op0) == LABEL_DECL
4245 && TREE_CODE (op1) == LABEL_DECL)
4246 return null_pointer_node;
4248 if (TREE_CODE (op0) == STRING_CST
4249 && TREE_CODE (op1) == STRING_CST
4250 && operand_equal_p (op0, op1, 1))
4251 return null_pointer_node;
4254 return NULL_TREE;
4257 /* Helper function of initializer_constant_valid_p.
4258 Return nonzero if VALUE is a valid constant-valued expression
4259 for use in initializing a static variable; one that can be an
4260 element of a "constant" initializer.
4262 Return null_pointer_node if the value is absolute;
4263 if it is relocatable, return the variable that determines the relocation.
4264 We assume that VALUE has been folded as much as possible;
4265 therefore, we do not need to check for such things as
4266 arithmetic-combinations of integers.
4268 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4270 static tree
4271 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4273 tree ret;
4275 switch (TREE_CODE (value))
4277 case CONSTRUCTOR:
4278 if (constructor_static_from_elts_p (value))
4280 unsigned HOST_WIDE_INT idx;
4281 tree elt;
4282 bool absolute = true;
4284 if (cache && cache[0] == value)
4285 return cache[1];
4286 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4288 tree reloc;
4289 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4290 NULL);
4291 if (!reloc)
4293 if (cache)
4295 cache[0] = value;
4296 cache[1] = NULL_TREE;
4298 return NULL_TREE;
4300 if (reloc != null_pointer_node)
4301 absolute = false;
4303 /* For a non-absolute relocation, there is no single
4304 variable that can be "the variable that determines the
4305 relocation." */
4306 if (cache)
4308 cache[0] = value;
4309 cache[1] = absolute ? null_pointer_node : error_mark_node;
4311 return absolute ? null_pointer_node : error_mark_node;
4314 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4316 case INTEGER_CST:
4317 case VECTOR_CST:
4318 case REAL_CST:
4319 case FIXED_CST:
4320 case STRING_CST:
4321 case COMPLEX_CST:
4322 return null_pointer_node;
4324 case ADDR_EXPR:
4325 case FDESC_EXPR:
4327 tree op0 = staticp (TREE_OPERAND (value, 0));
4328 if (op0)
4330 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4331 to be a constant, this is old-skool offsetof-like nonsense. */
4332 if (TREE_CODE (op0) == INDIRECT_REF
4333 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4334 return null_pointer_node;
4335 /* Taking the address of a nested function involves a trampoline,
4336 unless we don't need or want one. */
4337 if (TREE_CODE (op0) == FUNCTION_DECL
4338 && DECL_STATIC_CHAIN (op0)
4339 && !TREE_NO_TRAMPOLINE (value))
4340 return NULL_TREE;
4341 /* "&{...}" requires a temporary to hold the constructed
4342 object. */
4343 if (TREE_CODE (op0) == CONSTRUCTOR)
4344 return NULL_TREE;
4346 return op0;
4349 case NON_LVALUE_EXPR:
4350 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4351 endtype, cache);
4353 case VIEW_CONVERT_EXPR:
4355 tree src = TREE_OPERAND (value, 0);
4356 tree src_type = TREE_TYPE (src);
4357 tree dest_type = TREE_TYPE (value);
4359 /* Allow view-conversions from aggregate to non-aggregate type only
4360 if the bit pattern is fully preserved afterwards; otherwise, the
4361 RTL expander won't be able to apply a subsequent transformation
4362 to the underlying constructor. */
4363 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4365 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4366 return initializer_constant_valid_p_1 (src, endtype, cache);
4367 else
4368 return NULL_TREE;
4371 /* Allow all other kinds of view-conversion. */
4372 return initializer_constant_valid_p_1 (src, endtype, cache);
4375 CASE_CONVERT:
4377 tree src = TREE_OPERAND (value, 0);
4378 tree src_type = TREE_TYPE (src);
4379 tree dest_type = TREE_TYPE (value);
4381 /* Allow conversions between pointer types, floating-point
4382 types, and offset types. */
4383 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4384 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4385 || (TREE_CODE (dest_type) == OFFSET_TYPE
4386 && TREE_CODE (src_type) == OFFSET_TYPE))
4387 return initializer_constant_valid_p_1 (src, endtype, cache);
4389 /* Allow length-preserving conversions between integer types. */
4390 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4391 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4392 return initializer_constant_valid_p_1 (src, endtype, cache);
4394 /* Allow conversions between other integer types only if
4395 explicit value. */
4396 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type))
4398 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4399 if (inner == null_pointer_node)
4400 return null_pointer_node;
4401 break;
4404 /* Allow (int) &foo provided int is as wide as a pointer. */
4405 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4406 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4407 return initializer_constant_valid_p_1 (src, endtype, cache);
4409 /* Likewise conversions from int to pointers, but also allow
4410 conversions from 0. */
4411 if ((POINTER_TYPE_P (dest_type)
4412 || TREE_CODE (dest_type) == OFFSET_TYPE)
4413 && INTEGRAL_TYPE_P (src_type))
4415 if (TREE_CODE (src) == INTEGER_CST
4416 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4417 return null_pointer_node;
4418 if (integer_zerop (src))
4419 return null_pointer_node;
4420 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4421 return initializer_constant_valid_p_1 (src, endtype, cache);
4424 /* Allow conversions to struct or union types if the value
4425 inside is okay. */
4426 if (TREE_CODE (dest_type) == RECORD_TYPE
4427 || TREE_CODE (dest_type) == UNION_TYPE)
4428 return initializer_constant_valid_p_1 (src, endtype, cache);
4430 break;
4432 case POINTER_PLUS_EXPR:
4433 case PLUS_EXPR:
4434 /* Any valid floating-point constants will have been folded by now;
4435 with -frounding-math we hit this with addition of two constants. */
4436 if (TREE_CODE (endtype) == REAL_TYPE)
4437 return NULL_TREE;
4438 if (cache && cache[0] == value)
4439 return cache[1];
4440 if (! INTEGRAL_TYPE_P (endtype)
4441 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4443 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4444 tree valid0
4445 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4446 endtype, ncache);
4447 tree valid1
4448 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4449 endtype, ncache + 2);
4450 /* If either term is absolute, use the other term's relocation. */
4451 if (valid0 == null_pointer_node)
4452 ret = valid1;
4453 else if (valid1 == null_pointer_node)
4454 ret = valid0;
4455 /* Support narrowing pointer differences. */
4456 else
4457 ret = narrowing_initializer_constant_valid_p (value, endtype,
4458 ncache);
4460 else
4461 /* Support narrowing pointer differences. */
4462 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4463 if (cache)
4465 cache[0] = value;
4466 cache[1] = ret;
4468 return ret;
4470 case MINUS_EXPR:
4471 if (TREE_CODE (endtype) == REAL_TYPE)
4472 return NULL_TREE;
4473 if (cache && cache[0] == value)
4474 return cache[1];
4475 if (! INTEGRAL_TYPE_P (endtype)
4476 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4478 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4479 tree valid0
4480 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4481 endtype, ncache);
4482 tree valid1
4483 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4484 endtype, ncache + 2);
4485 /* Win if second argument is absolute. */
4486 if (valid1 == null_pointer_node)
4487 ret = valid0;
4488 /* Win if both arguments have the same relocation.
4489 Then the value is absolute. */
4490 else if (valid0 == valid1 && valid0 != 0)
4491 ret = null_pointer_node;
4492 /* Since GCC guarantees that string constants are unique in the
4493 generated code, a subtraction between two copies of the same
4494 constant string is absolute. */
4495 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4496 && valid1 && TREE_CODE (valid1) == STRING_CST
4497 && operand_equal_p (valid0, valid1, 1))
4498 ret = null_pointer_node;
4499 /* Support narrowing differences. */
4500 else
4501 ret = narrowing_initializer_constant_valid_p (value, endtype,
4502 ncache);
4504 else
4505 /* Support narrowing differences. */
4506 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4507 if (cache)
4509 cache[0] = value;
4510 cache[1] = ret;
4512 return ret;
4514 default:
4515 break;
4518 return NULL_TREE;
4521 /* Return nonzero if VALUE is a valid constant-valued expression
4522 for use in initializing a static variable; one that can be an
4523 element of a "constant" initializer.
4525 Return null_pointer_node if the value is absolute;
4526 if it is relocatable, return the variable that determines the relocation.
4527 We assume that VALUE has been folded as much as possible;
4528 therefore, we do not need to check for such things as
4529 arithmetic-combinations of integers. */
4530 tree
4531 initializer_constant_valid_p (tree value, tree endtype)
4533 return initializer_constant_valid_p_1 (value, endtype, NULL);
4536 /* Return true if VALUE is a valid constant-valued expression
4537 for use in initializing a static bit-field; one that can be
4538 an element of a "constant" initializer. */
4540 bool
4541 initializer_constant_valid_for_bitfield_p (tree value)
4543 /* For bitfields we support integer constants or possibly nested aggregates
4544 of such. */
4545 switch (TREE_CODE (value))
4547 case CONSTRUCTOR:
4549 unsigned HOST_WIDE_INT idx;
4550 tree elt;
4552 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4553 if (!initializer_constant_valid_for_bitfield_p (elt))
4554 return false;
4555 return true;
4558 case INTEGER_CST:
4559 case REAL_CST:
4560 return true;
4562 case VIEW_CONVERT_EXPR:
4563 case NON_LVALUE_EXPR:
4564 return
4565 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4567 default:
4568 break;
4571 return false;
4574 /* output_constructor outer state of relevance in recursive calls, typically
4575 for nested aggregate bitfields. */
4577 typedef struct {
4578 unsigned int bit_offset; /* current position in ... */
4579 int byte; /* ... the outer byte buffer. */
4580 } oc_outer_state;
4582 static unsigned HOST_WIDE_INT
4583 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int,
4584 oc_outer_state *);
4586 /* Output assembler code for constant EXP, with no label.
4587 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4588 Assumes output_addressed_constants has been done on EXP already.
4590 Generate exactly SIZE bytes of assembler data, padding at the end
4591 with zeros if necessary. SIZE must always be specified.
4593 SIZE is important for structure constructors,
4594 since trailing members may have been omitted from the constructor.
4595 It is also important for initialization of arrays from string constants
4596 since the full length of the string constant might not be wanted.
4597 It is also needed for initialization of unions, where the initializer's
4598 type is just one member, and that may not be as long as the union.
4600 There a case in which we would fail to output exactly SIZE bytes:
4601 for a structure constructor that wants to produce more than SIZE bytes.
4602 But such constructors will never be generated for any possible input.
4604 ALIGN is the alignment of the data in bits. */
4606 void
4607 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align)
4609 enum tree_code code;
4610 unsigned HOST_WIDE_INT thissize;
4612 if (size == 0 || flag_syntax_only)
4613 return;
4615 /* See if we're trying to initialize a pointer in a non-default mode
4616 to the address of some declaration somewhere. If the target says
4617 the mode is valid for pointers, assume the target has a way of
4618 resolving it. */
4619 if (TREE_CODE (exp) == NOP_EXPR
4620 && POINTER_TYPE_P (TREE_TYPE (exp))
4621 && targetm.addr_space.valid_pointer_mode
4622 (TYPE_MODE (TREE_TYPE (exp)),
4623 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4625 tree saved_type = TREE_TYPE (exp);
4627 /* Peel off any intermediate conversions-to-pointer for valid
4628 pointer modes. */
4629 while (TREE_CODE (exp) == NOP_EXPR
4630 && POINTER_TYPE_P (TREE_TYPE (exp))
4631 && targetm.addr_space.valid_pointer_mode
4632 (TYPE_MODE (TREE_TYPE (exp)),
4633 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4634 exp = TREE_OPERAND (exp, 0);
4636 /* If what we're left with is the address of something, we can
4637 convert the address to the final type and output it that
4638 way. */
4639 if (TREE_CODE (exp) == ADDR_EXPR)
4640 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4641 /* Likewise for constant ints. */
4642 else if (TREE_CODE (exp) == INTEGER_CST)
4643 exp = build_int_cst_wide (saved_type, TREE_INT_CST_LOW (exp),
4644 TREE_INT_CST_HIGH (exp));
4648 /* Eliminate any conversions since we'll be outputting the underlying
4649 constant. */
4650 while (CONVERT_EXPR_P (exp)
4651 || TREE_CODE (exp) == NON_LVALUE_EXPR
4652 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4654 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4655 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4657 /* Make sure eliminating the conversion is really a no-op, except with
4658 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4659 union types to allow for Ada unchecked unions. */
4660 if (type_size > op_size
4661 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4662 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4663 /* Keep the conversion. */
4664 break;
4665 else
4666 exp = TREE_OPERAND (exp, 0);
4669 code = TREE_CODE (TREE_TYPE (exp));
4670 thissize = int_size_in_bytes (TREE_TYPE (exp));
4672 /* Allow a constructor with no elements for any data type.
4673 This means to fill the space with zeros. */
4674 if (TREE_CODE (exp) == CONSTRUCTOR
4675 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4677 assemble_zeros (size);
4678 return;
4681 if (TREE_CODE (exp) == FDESC_EXPR)
4683 #ifdef ASM_OUTPUT_FDESC
4684 HOST_WIDE_INT part = tree_low_cst (TREE_OPERAND (exp, 1), 0);
4685 tree decl = TREE_OPERAND (exp, 0);
4686 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4687 #else
4688 gcc_unreachable ();
4689 #endif
4690 return;
4693 /* Now output the underlying data. If we've handling the padding, return.
4694 Otherwise, break and ensure SIZE is the size written. */
4695 switch (code)
4697 case BOOLEAN_TYPE:
4698 case INTEGER_TYPE:
4699 case ENUMERAL_TYPE:
4700 case POINTER_TYPE:
4701 case REFERENCE_TYPE:
4702 case OFFSET_TYPE:
4703 case FIXED_POINT_TYPE:
4704 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
4705 EXPAND_INITIALIZER),
4706 MIN (size, thissize), align, 0))
4707 error ("initializer for integer/fixed-point value is too complicated");
4708 break;
4710 case REAL_TYPE:
4711 if (TREE_CODE (exp) != REAL_CST)
4712 error ("initializer for floating value is not a floating constant");
4713 else
4714 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)), align);
4715 break;
4717 case COMPLEX_TYPE:
4718 output_constant (TREE_REALPART (exp), thissize / 2, align);
4719 output_constant (TREE_IMAGPART (exp), thissize / 2,
4720 min_align (align, BITS_PER_UNIT * (thissize / 2)));
4721 break;
4723 case ARRAY_TYPE:
4724 case VECTOR_TYPE:
4725 switch (TREE_CODE (exp))
4727 case CONSTRUCTOR:
4728 output_constructor (exp, size, align, NULL);
4729 return;
4730 case STRING_CST:
4731 thissize
4732 = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4733 assemble_string (TREE_STRING_POINTER (exp), thissize);
4734 break;
4735 case VECTOR_CST:
4737 enum machine_mode inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4738 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4739 int elt_size = GET_MODE_SIZE (inner);
4740 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align);
4741 thissize = elt_size;
4742 for (unsigned int i = 1; i < VECTOR_CST_NELTS (exp); i++)
4744 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign);
4745 thissize += elt_size;
4747 break;
4749 default:
4750 gcc_unreachable ();
4752 break;
4754 case RECORD_TYPE:
4755 case UNION_TYPE:
4756 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4757 output_constructor (exp, size, align, NULL);
4758 return;
4760 case ERROR_MARK:
4761 return;
4763 default:
4764 gcc_unreachable ();
4767 if (size > thissize)
4768 assemble_zeros (size - thissize);
4772 /* Subroutine of output_constructor, used for computing the size of
4773 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4774 type with an unspecified upper bound. */
4776 static unsigned HOST_WIDE_INT
4777 array_size_for_constructor (tree val)
4779 tree max_index;
4780 unsigned HOST_WIDE_INT cnt;
4781 tree index, value, tmp;
4782 double_int i;
4784 /* This code used to attempt to handle string constants that are not
4785 arrays of single-bytes, but nothing else does, so there's no point in
4786 doing it here. */
4787 if (TREE_CODE (val) == STRING_CST)
4788 return TREE_STRING_LENGTH (val);
4790 max_index = NULL_TREE;
4791 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
4793 if (TREE_CODE (index) == RANGE_EXPR)
4794 index = TREE_OPERAND (index, 1);
4795 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
4796 max_index = index;
4799 if (max_index == NULL_TREE)
4800 return 0;
4802 /* Compute the total number of array elements. */
4803 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
4804 i = tree_to_double_int (max_index) - tree_to_double_int (tmp);
4805 i += double_int_one;
4807 /* Multiply by the array element unit size to find number of bytes. */
4808 i *= tree_to_double_int (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
4810 gcc_assert (i.fits_uhwi ());
4811 return i.low;
4814 /* Other datastructures + helpers for output_constructor. */
4816 /* output_constructor local state to support interaction with helpers. */
4818 typedef struct {
4820 /* Received arguments. */
4821 tree exp; /* Constructor expression. */
4822 tree type; /* Type of constructor expression. */
4823 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */
4824 unsigned int align; /* Known initial alignment. */
4825 tree min_index; /* Lower bound if specified for an array. */
4827 /* Output processing state. */
4828 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */
4829 int byte; /* Part of a bitfield byte yet to be output. */
4830 int last_relative_index; /* Implicit or explicit index of the last
4831 array element output within a bitfield. */
4832 bool byte_buffer_in_use; /* Whether BYTE is in use. */
4834 /* Current element. */
4835 tree field; /* Current field decl in a record. */
4836 tree val; /* Current element value. */
4837 tree index; /* Current element index. */
4839 } oc_local_state;
4841 /* Helper for output_constructor. From the current LOCAL state, output a
4842 RANGE_EXPR element. */
4844 static void
4845 output_constructor_array_range (oc_local_state *local)
4847 unsigned HOST_WIDE_INT fieldsize
4848 = int_size_in_bytes (TREE_TYPE (local->type));
4850 HOST_WIDE_INT lo_index
4851 = tree_low_cst (TREE_OPERAND (local->index, 0), 0);
4852 HOST_WIDE_INT hi_index
4853 = tree_low_cst (TREE_OPERAND (local->index, 1), 0);
4854 HOST_WIDE_INT index;
4856 unsigned int align2
4857 = min_align (local->align, fieldsize * BITS_PER_UNIT);
4859 for (index = lo_index; index <= hi_index; index++)
4861 /* Output the element's initial value. */
4862 if (local->val == NULL_TREE)
4863 assemble_zeros (fieldsize);
4864 else
4865 output_constant (local->val, fieldsize, align2);
4867 /* Count its size. */
4868 local->total_bytes += fieldsize;
4872 /* Helper for output_constructor. From the current LOCAL state, output a
4873 field element that is not true bitfield or part of an outer one. */
4875 static void
4876 output_constructor_regular_field (oc_local_state *local)
4878 /* Field size and position. Since this structure is static, we know the
4879 positions are constant. */
4880 unsigned HOST_WIDE_INT fieldsize;
4881 HOST_WIDE_INT fieldpos;
4883 unsigned int align2;
4885 if (local->index != NULL_TREE)
4887 /* Perform the index calculation in modulo arithmetic but
4888 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
4889 but we are using an unsigned sizetype. */
4890 unsigned prec = TYPE_PRECISION (sizetype);
4891 double_int idx = tree_to_double_int (local->index)
4892 - tree_to_double_int (local->min_index);
4893 idx = idx.sext (prec);
4894 fieldpos = (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (local->val)), 1)
4895 * idx.low);
4897 else if (local->field != NULL_TREE)
4898 fieldpos = int_byte_position (local->field);
4899 else
4900 fieldpos = 0;
4902 /* Output any buffered-up bit-fields preceding this element. */
4903 if (local->byte_buffer_in_use)
4905 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4906 local->total_bytes++;
4907 local->byte_buffer_in_use = false;
4910 /* Advance to offset of this element.
4911 Note no alignment needed in an array, since that is guaranteed
4912 if each element has the proper size. */
4913 if ((local->field != NULL_TREE || local->index != NULL_TREE)
4914 && fieldpos != local->total_bytes)
4916 gcc_assert (fieldpos >= local->total_bytes);
4917 assemble_zeros (fieldpos - local->total_bytes);
4918 local->total_bytes = fieldpos;
4921 /* Find the alignment of this element. */
4922 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
4924 /* Determine size this element should occupy. */
4925 if (local->field)
4927 fieldsize = 0;
4929 /* If this is an array with an unspecified upper bound,
4930 the initializer determines the size. */
4931 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
4932 but we cannot do this until the deprecated support for
4933 initializing zero-length array members is removed. */
4934 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
4935 && TYPE_DOMAIN (TREE_TYPE (local->field))
4936 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field))))
4938 fieldsize = array_size_for_constructor (local->val);
4939 /* Given a non-empty initialization, this field had
4940 better be last. */
4941 gcc_assert (!fieldsize || !DECL_CHAIN (local->field));
4943 else
4944 fieldsize = tree_low_cst (DECL_SIZE_UNIT (local->field), 1);
4946 else
4947 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
4949 /* Output the element's initial value. */
4950 if (local->val == NULL_TREE)
4951 assemble_zeros (fieldsize);
4952 else
4953 output_constant (local->val, fieldsize, align2);
4955 /* Count its size. */
4956 local->total_bytes += fieldsize;
4959 /* Helper for output_constructor. From the LOCAL state, output an element
4960 that is a true bitfield or part of an outer one. BIT_OFFSET is the offset
4961 from the start of a possibly ongoing outer byte buffer. */
4963 static void
4964 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
4966 /* Bit size of this element. */
4967 HOST_WIDE_INT ebitsize
4968 = (local->field
4969 ? tree_low_cst (DECL_SIZE (local->field), 1)
4970 : tree_low_cst (TYPE_SIZE (TREE_TYPE (local->type)), 1));
4972 /* Relative index of this element if this is an array component. */
4973 HOST_WIDE_INT relative_index
4974 = (!local->field
4975 ? (local->index
4976 ? (tree_low_cst (local->index, 0)
4977 - tree_low_cst (local->min_index, 0))
4978 : local->last_relative_index + 1)
4979 : 0);
4981 /* Bit position of this element from the start of the containing
4982 constructor. */
4983 HOST_WIDE_INT constructor_relative_ebitpos
4984 = (local->field
4985 ? int_bit_position (local->field)
4986 : ebitsize * relative_index);
4988 /* Bit position of this element from the start of a possibly ongoing
4989 outer byte buffer. */
4990 HOST_WIDE_INT byte_relative_ebitpos
4991 = bit_offset + constructor_relative_ebitpos;
4993 /* From the start of a possibly ongoing outer byte buffer, offsets to
4994 the first bit of this element and to the first bit past the end of
4995 this element. */
4996 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
4997 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
4999 local->last_relative_index = relative_index;
5001 if (local->val == NULL_TREE)
5002 local->val = integer_zero_node;
5004 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
5005 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
5006 local->val = TREE_OPERAND (local->val, 0);
5008 if (TREE_CODE (local->val) != INTEGER_CST
5009 && TREE_CODE (local->val) != CONSTRUCTOR)
5011 error ("invalid initial value for member %qE", DECL_NAME (local->field));
5012 return;
5015 /* If this field does not start in this (or next) byte, skip some bytes. */
5016 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5018 /* Output remnant of any bit field in previous bytes. */
5019 if (local->byte_buffer_in_use)
5021 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5022 local->total_bytes++;
5023 local->byte_buffer_in_use = false;
5026 /* If still not at proper byte, advance to there. */
5027 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5029 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
5030 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
5031 local->total_bytes = next_offset / BITS_PER_UNIT;
5035 /* Set up the buffer if necessary. */
5036 if (!local->byte_buffer_in_use)
5038 local->byte = 0;
5039 if (ebitsize > 0)
5040 local->byte_buffer_in_use = true;
5043 /* If this is nested constructor, recurse passing the bit offset and the
5044 pending data, then retrieve the new pending data afterwards. */
5045 if (TREE_CODE (local->val) == CONSTRUCTOR)
5047 oc_outer_state temp_state;
5048 temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5049 temp_state.byte = local->byte;
5050 local->total_bytes
5051 += output_constructor (local->val, 0, 0, &temp_state);
5052 local->byte = temp_state.byte;
5053 return;
5056 /* Otherwise, we must split the element into pieces that fall within
5057 separate bytes, and combine each byte with previous or following
5058 bit-fields. */
5059 while (next_offset < end_offset)
5061 int this_time;
5062 int shift;
5063 HOST_WIDE_INT value;
5064 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5065 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5067 /* Advance from byte to byte within this element when necessary. */
5068 while (next_byte != local->total_bytes)
5070 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5071 local->total_bytes++;
5072 local->byte = 0;
5075 /* Number of bits we can process at once (all part of the same byte). */
5076 this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5077 if (BYTES_BIG_ENDIAN)
5079 /* On big-endian machine, take the most significant bits
5080 first (of the bits that are significant)
5081 and put them into bytes from the most significant end. */
5082 shift = end_offset - next_offset - this_time;
5084 /* Don't try to take a bunch of bits that cross
5085 the word boundary in the INTEGER_CST. We can
5086 only select bits from the LOW or HIGH part
5087 not from both. */
5088 if (shift < HOST_BITS_PER_WIDE_INT
5089 && shift + this_time > HOST_BITS_PER_WIDE_INT)
5091 this_time = shift + this_time - HOST_BITS_PER_WIDE_INT;
5092 shift = HOST_BITS_PER_WIDE_INT;
5095 /* Now get the bits from the appropriate constant word. */
5096 if (shift < HOST_BITS_PER_WIDE_INT)
5097 value = TREE_INT_CST_LOW (local->val);
5098 else
5100 gcc_assert (shift < HOST_BITS_PER_DOUBLE_INT);
5101 value = TREE_INT_CST_HIGH (local->val);
5102 shift -= HOST_BITS_PER_WIDE_INT;
5105 /* Get the result. This works only when:
5106 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5107 local->byte |= (((value >> shift)
5108 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5109 << (BITS_PER_UNIT - this_time - next_bit));
5111 else
5113 /* On little-endian machines,
5114 take first the least significant bits of the value
5115 and pack them starting at the least significant
5116 bits of the bytes. */
5117 shift = next_offset - byte_relative_ebitpos;
5119 /* Don't try to take a bunch of bits that cross
5120 the word boundary in the INTEGER_CST. We can
5121 only select bits from the LOW or HIGH part
5122 not from both. */
5123 if (shift < HOST_BITS_PER_WIDE_INT
5124 && shift + this_time > HOST_BITS_PER_WIDE_INT)
5125 this_time = (HOST_BITS_PER_WIDE_INT - shift);
5127 /* Now get the bits from the appropriate constant word. */
5128 if (shift < HOST_BITS_PER_WIDE_INT)
5129 value = TREE_INT_CST_LOW (local->val);
5130 else
5132 gcc_assert (shift < HOST_BITS_PER_DOUBLE_INT);
5133 value = TREE_INT_CST_HIGH (local->val);
5134 shift -= HOST_BITS_PER_WIDE_INT;
5137 /* Get the result. This works only when:
5138 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5139 local->byte |= (((value >> shift)
5140 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5141 << next_bit);
5144 next_offset += this_time;
5145 local->byte_buffer_in_use = true;
5149 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5150 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5151 caller output state of relevance in recursive invocations. */
5153 static unsigned HOST_WIDE_INT
5154 output_constructor (tree exp, unsigned HOST_WIDE_INT size,
5155 unsigned int align, oc_outer_state *outer)
5157 unsigned HOST_WIDE_INT cnt;
5158 constructor_elt *ce;
5160 oc_local_state local;
5162 /* Setup our local state to communicate with helpers. */
5163 local.exp = exp;
5164 local.type = TREE_TYPE (exp);
5165 local.size = size;
5166 local.align = align;
5167 if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5168 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5169 else
5170 local.min_index = NULL_TREE;
5172 local.total_bytes = 0;
5173 local.byte_buffer_in_use = outer != NULL;
5174 local.byte = outer ? outer->byte : 0;
5175 local.last_relative_index = -1;
5177 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5179 /* As CE goes through the elements of the constant, FIELD goes through the
5180 structure fields if the constant is a structure. If the constant is a
5181 union, we override this by getting the field from the TREE_LIST element.
5182 But the constant could also be an array. Then FIELD is zero.
5184 There is always a maximum of one element in the chain LINK for unions
5185 (even if the initializer in a source program incorrectly contains
5186 more one). */
5188 if (TREE_CODE (local.type) == RECORD_TYPE)
5189 local.field = TYPE_FIELDS (local.type);
5190 else
5191 local.field = NULL_TREE;
5193 for (cnt = 0;
5194 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5195 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5197 local.val = ce->value;
5198 local.index = NULL_TREE;
5200 /* The element in a union constructor specifies the proper field
5201 or index. */
5202 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5203 local.field = ce->index;
5205 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5206 local.index = ce->index;
5208 if (local.field && flag_verbose_asm)
5209 fprintf (asm_out_file, "%s %s:\n",
5210 ASM_COMMENT_START,
5211 DECL_NAME (local.field)
5212 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5213 : "<anonymous>");
5215 /* Eliminate the marker that makes a cast not be an lvalue. */
5216 if (local.val != NULL_TREE)
5217 STRIP_NOPS (local.val);
5219 /* Output the current element, using the appropriate helper ... */
5221 /* For an array slice not part of an outer bitfield. */
5222 if (!outer
5223 && local.index != NULL_TREE
5224 && TREE_CODE (local.index) == RANGE_EXPR)
5225 output_constructor_array_range (&local);
5227 /* For a field that is neither a true bitfield nor part of an outer one,
5228 known to be at least byte aligned and multiple-of-bytes long. */
5229 else if (!outer
5230 && (local.field == NULL_TREE
5231 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5232 output_constructor_regular_field (&local);
5234 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5235 supported for scalar fields, so we may need to convert first. */
5236 else
5238 if (TREE_CODE (local.val) == REAL_CST)
5239 local.val
5240 = fold_unary (VIEW_CONVERT_EXPR,
5241 build_nonstandard_integer_type
5242 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5243 local.val);
5244 output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5248 /* If we are not at toplevel, save the pending data for our caller.
5249 Otherwise output the pending data and padding zeros as needed. */
5250 if (outer)
5251 outer->byte = local.byte;
5252 else
5254 if (local.byte_buffer_in_use)
5256 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5257 local.total_bytes++;
5260 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5262 assemble_zeros (local.size - local.total_bytes);
5263 local.total_bytes = local.size;
5267 return local.total_bytes;
5270 /* Mark DECL as weak. */
5272 static void
5273 mark_weak (tree decl)
5275 DECL_WEAK (decl) = 1;
5277 if (DECL_RTL_SET_P (decl)
5278 && MEM_P (DECL_RTL (decl))
5279 && XEXP (DECL_RTL (decl), 0)
5280 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5281 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5284 /* Merge weak status between NEWDECL and OLDDECL. */
5286 void
5287 merge_weak (tree newdecl, tree olddecl)
5289 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5291 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5293 tree *pwd;
5294 /* We put the NEWDECL on the weak_decls list at some point
5295 and OLDDECL as well. Keep just OLDDECL on the list. */
5296 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5297 if (TREE_VALUE (*pwd) == newdecl)
5299 *pwd = TREE_CHAIN (*pwd);
5300 break;
5303 return;
5306 if (DECL_WEAK (newdecl))
5308 tree wd;
5310 /* NEWDECL is weak, but OLDDECL is not. */
5312 /* If we already output the OLDDECL, we're in trouble; we can't
5313 go back and make it weak. This should never happen in
5314 unit-at-a-time compilation. */
5315 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5317 /* If we've already generated rtl referencing OLDDECL, we may
5318 have done so in a way that will not function properly with
5319 a weak symbol. Again in unit-at-a-time this should be
5320 impossible. */
5321 gcc_assert (!TREE_USED (olddecl)
5322 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5324 if (TARGET_SUPPORTS_WEAK)
5326 /* We put the NEWDECL on the weak_decls list at some point.
5327 Replace it with the OLDDECL. */
5328 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5329 if (TREE_VALUE (wd) == newdecl)
5331 TREE_VALUE (wd) = olddecl;
5332 break;
5334 /* We may not find the entry on the list. If NEWDECL is a
5335 weak alias, then we will have already called
5336 globalize_decl to remove the entry; in that case, we do
5337 not need to do anything. */
5340 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5341 mark_weak (olddecl);
5343 else
5344 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5345 weak. Just update NEWDECL to indicate that it's weak too. */
5346 mark_weak (newdecl);
5349 /* Declare DECL to be a weak symbol. */
5351 void
5352 declare_weak (tree decl)
5354 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5355 if (! TREE_PUBLIC (decl))
5356 error ("weak declaration of %q+D must be public", decl);
5357 else if (!TARGET_SUPPORTS_WEAK)
5358 warning (0, "weak declaration of %q+D not supported", decl);
5360 mark_weak (decl);
5361 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5362 DECL_ATTRIBUTES (decl)
5363 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5366 static void
5367 weak_finish_1 (tree decl)
5369 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5370 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5371 #endif
5373 if (! TREE_USED (decl))
5374 return;
5376 #ifdef ASM_WEAKEN_DECL
5377 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5378 #else
5379 #ifdef ASM_WEAKEN_LABEL
5380 ASM_WEAKEN_LABEL (asm_out_file, name);
5381 #else
5382 #ifdef ASM_OUTPUT_WEAK_ALIAS
5384 static bool warn_once = 0;
5385 if (! warn_once)
5387 warning (0, "only weak aliases are supported in this configuration");
5388 warn_once = 1;
5390 return;
5392 #endif
5393 #endif
5394 #endif
5397 /* Fiven an assembly name, find the decl it is associated with. */
5398 static tree
5399 find_decl (tree target)
5401 symtab_node node = symtab_node_for_asm (target);
5402 if (node)
5403 return node->symbol.decl;
5404 return NULL_TREE;
5407 /* This TREE_LIST contains weakref targets. */
5409 static GTY(()) tree weakref_targets;
5411 /* Emit any pending weak declarations. */
5413 void
5414 weak_finish (void)
5416 tree t;
5418 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5420 tree alias_decl = TREE_PURPOSE (t);
5421 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5423 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5424 /* Remove alias_decl from the weak list, but leave entries for
5425 the target alone. */
5426 target = NULL_TREE;
5427 #ifndef ASM_OUTPUT_WEAKREF
5428 else if (! TREE_SYMBOL_REFERENCED (target))
5430 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5431 defined, otherwise we and weak_finish_1 would use
5432 different macros. */
5433 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5434 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5435 # else
5436 tree decl = find_decl (target);
5438 if (! decl)
5440 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5441 TREE_CODE (alias_decl), target,
5442 TREE_TYPE (alias_decl));
5444 DECL_EXTERNAL (decl) = 1;
5445 TREE_PUBLIC (decl) = 1;
5446 DECL_ARTIFICIAL (decl) = 1;
5447 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5448 TREE_USED (decl) = 1;
5451 weak_finish_1 (decl);
5452 # endif
5454 #endif
5457 tree *p;
5458 tree t2;
5460 /* Remove the alias and the target from the pending weak list
5461 so that we do not emit any .weak directives for the former,
5462 nor multiple .weak directives for the latter. */
5463 for (p = &weak_decls; (t2 = *p) ; )
5465 if (TREE_VALUE (t2) == alias_decl
5466 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5467 *p = TREE_CHAIN (t2);
5468 else
5469 p = &TREE_CHAIN (t2);
5472 /* Remove other weakrefs to the same target, to speed things up. */
5473 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5475 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5476 *p = TREE_CHAIN (t2);
5477 else
5478 p = &TREE_CHAIN (t2);
5483 for (t = weak_decls; t; t = TREE_CHAIN (t))
5485 tree decl = TREE_VALUE (t);
5487 weak_finish_1 (decl);
5491 /* Emit the assembly bits to indicate that DECL is globally visible. */
5493 static void
5494 globalize_decl (tree decl)
5497 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5498 if (DECL_WEAK (decl))
5500 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5501 tree *p, t;
5503 #ifdef ASM_WEAKEN_DECL
5504 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5505 #else
5506 ASM_WEAKEN_LABEL (asm_out_file, name);
5507 #endif
5509 /* Remove this function from the pending weak list so that
5510 we do not emit multiple .weak directives for it. */
5511 for (p = &weak_decls; (t = *p) ; )
5513 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5514 *p = TREE_CHAIN (t);
5515 else
5516 p = &TREE_CHAIN (t);
5519 /* Remove weakrefs to the same target from the pending weakref
5520 list, for the same reason. */
5521 for (p = &weakref_targets; (t = *p) ; )
5523 if (DECL_ASSEMBLER_NAME (decl)
5524 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5525 *p = TREE_CHAIN (t);
5526 else
5527 p = &TREE_CHAIN (t);
5530 return;
5532 #endif
5534 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5537 vec<alias_pair, va_gc> *alias_pairs;
5539 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5540 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5541 tree node is DECL to have the value of the tree node TARGET. */
5543 void
5544 do_assemble_alias (tree decl, tree target)
5546 /* Emulated TLS had better not get this var. */
5547 gcc_assert(!(!targetm.have_tls
5548 && TREE_CODE (decl) == VAR_DECL
5549 && DECL_THREAD_LOCAL_P (decl)));
5551 if (TREE_ASM_WRITTEN (decl))
5552 return;
5554 /* We must force creation of DECL_RTL for debug info generation, even though
5555 we don't use it here. */
5556 make_decl_rtl (decl);
5558 TREE_ASM_WRITTEN (decl) = 1;
5559 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5561 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5563 ultimate_transparent_alias_target (&target);
5565 if (!TREE_SYMBOL_REFERENCED (target))
5566 weakref_targets = tree_cons (decl, target, weakref_targets);
5568 #ifdef ASM_OUTPUT_WEAKREF
5569 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5570 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5571 IDENTIFIER_POINTER (target));
5572 #else
5573 if (!TARGET_SUPPORTS_WEAK)
5575 error_at (DECL_SOURCE_LOCATION (decl),
5576 "weakref is not supported in this configuration");
5577 return;
5579 #endif
5580 return;
5583 #ifdef ASM_OUTPUT_DEF
5584 /* Make name accessible from other files, if appropriate. */
5586 if (TREE_PUBLIC (decl))
5588 globalize_decl (decl);
5589 maybe_assemble_visibility (decl);
5591 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5593 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5594 if (targetm.has_ifunc_p ())
5595 ASM_OUTPUT_TYPE_DIRECTIVE
5596 (asm_out_file, IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5597 IFUNC_ASM_TYPE);
5598 else
5599 #endif
5600 error_at (DECL_SOURCE_LOCATION (decl),
5601 "ifunc is not supported on this target");
5604 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5605 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5606 # else
5607 ASM_OUTPUT_DEF (asm_out_file,
5608 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5609 IDENTIFIER_POINTER (target));
5610 # endif
5611 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5613 const char *name;
5614 tree *p, t;
5616 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5617 # ifdef ASM_WEAKEN_DECL
5618 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5619 # else
5620 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5621 # endif
5622 /* Remove this function from the pending weak list so that
5623 we do not emit multiple .weak directives for it. */
5624 for (p = &weak_decls; (t = *p) ; )
5625 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5626 *p = TREE_CHAIN (t);
5627 else
5628 p = &TREE_CHAIN (t);
5630 /* Remove weakrefs to the same target from the pending weakref
5631 list, for the same reason. */
5632 for (p = &weakref_targets; (t = *p) ; )
5634 if (DECL_ASSEMBLER_NAME (decl)
5635 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5636 *p = TREE_CHAIN (t);
5637 else
5638 p = &TREE_CHAIN (t);
5641 #endif
5644 /* Emit an assembler directive to make the symbol for DECL an alias to
5645 the symbol for TARGET. */
5647 void
5648 assemble_alias (tree decl, tree target)
5650 tree target_decl;
5652 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5654 tree alias = DECL_ASSEMBLER_NAME (decl);
5656 ultimate_transparent_alias_target (&target);
5658 if (alias == target)
5659 error ("weakref %q+D ultimately targets itself", decl);
5660 if (TREE_PUBLIC (decl))
5661 error ("weakref %q+D must have static linkage", decl);
5663 else
5665 #if !defined (ASM_OUTPUT_DEF)
5666 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5667 error_at (DECL_SOURCE_LOCATION (decl),
5668 "alias definitions not supported in this configuration");
5669 return;
5670 # else
5671 if (!DECL_WEAK (decl))
5673 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5674 error_at (DECL_SOURCE_LOCATION (decl),
5675 "ifunc is not supported in this configuration");
5676 else
5677 error_at (DECL_SOURCE_LOCATION (decl),
5678 "only weak aliases are supported in this configuration");
5679 return;
5681 # endif
5682 #endif
5684 TREE_USED (decl) = 1;
5686 /* Allow aliases to aliases. */
5687 if (TREE_CODE (decl) == FUNCTION_DECL)
5688 cgraph_get_create_node (decl)->symbol.alias = true;
5689 else
5690 varpool_node_for_decl (decl)->symbol.alias = true;
5692 /* If the target has already been emitted, we don't have to queue the
5693 alias. This saves a tad of memory. */
5694 if (cgraph_global_info_ready)
5695 target_decl = find_decl (target);
5696 else
5697 target_decl= NULL;
5698 if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5699 || cgraph_state >= CGRAPH_STATE_EXPANSION)
5700 do_assemble_alias (decl, target);
5701 else
5703 alias_pair p = {decl, target};
5704 vec_safe_push (alias_pairs, p);
5708 /* Record and output a table of translations from original function
5709 to its transaction aware clone. Note that tm_pure functions are
5710 considered to be their own clone. */
5712 static GTY((if_marked ("tree_map_marked_p"), param_is (struct tree_map)))
5713 htab_t tm_clone_hash;
5715 void
5716 record_tm_clone_pair (tree o, tree n)
5718 struct tree_map **slot, *h;
5720 if (tm_clone_hash == NULL)
5721 tm_clone_hash = htab_create_ggc (32, tree_map_hash, tree_map_eq, 0);
5723 h = ggc_alloc_tree_map ();
5724 h->hash = htab_hash_pointer (o);
5725 h->base.from = o;
5726 h->to = n;
5728 slot = (struct tree_map **)
5729 htab_find_slot_with_hash (tm_clone_hash, h, h->hash, INSERT);
5730 *slot = h;
5733 tree
5734 get_tm_clone_pair (tree o)
5736 if (tm_clone_hash)
5738 struct tree_map *h, in;
5740 in.base.from = o;
5741 in.hash = htab_hash_pointer (o);
5742 h = (struct tree_map *) htab_find_with_hash (tm_clone_hash,
5743 &in, in.hash);
5744 if (h)
5745 return h->to;
5747 return NULL_TREE;
5750 typedef struct tm_alias_pair
5752 unsigned int uid;
5753 tree from;
5754 tree to;
5755 } tm_alias_pair;
5758 /* Helper function for finish_tm_clone_pairs. Dump a hash table entry
5759 into a VEC in INFO. */
5761 static int
5762 dump_tm_clone_to_vec (void **slot, void *info)
5764 struct tree_map *map = (struct tree_map *) *slot;
5765 vec<tm_alias_pair> *tm_alias_pairs = (vec<tm_alias_pair> *) info;
5766 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
5767 tm_alias_pairs->safe_push (p);
5768 return 1;
5771 /* Dump the actual pairs to the .tm_clone_table section. */
5773 static void
5774 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
5776 unsigned i;
5777 tm_alias_pair *p;
5778 bool switched = false;
5780 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
5782 tree src = p->from;
5783 tree dst = p->to;
5784 struct cgraph_node *src_n = cgraph_get_node (src);
5785 struct cgraph_node *dst_n = cgraph_get_node (dst);
5787 /* The function ipa_tm_create_version() marks the clone as needed if
5788 the original function was needed. But we also mark the clone as
5789 needed if we ever called the clone indirectly through
5790 TM_GETTMCLONE. If neither of these are true, we didn't generate
5791 a clone, and we didn't call it indirectly... no sense keeping it
5792 in the clone table. */
5793 if (!dst_n || !dst_n->symbol.definition)
5794 continue;
5796 /* This covers the case where we have optimized the original
5797 function away, and only access the transactional clone. */
5798 if (!src_n || !src_n->symbol.definition)
5799 continue;
5801 if (!switched)
5803 switch_to_section (targetm.asm_out.tm_clone_table_section ());
5804 assemble_align (POINTER_SIZE);
5805 switched = true;
5808 assemble_integer (XEXP (DECL_RTL (src), 0),
5809 POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
5810 assemble_integer (XEXP (DECL_RTL (dst), 0),
5811 POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
5815 /* Provide a default for the tm_clone_table section. */
5817 section *
5818 default_clone_table_section (void)
5820 return get_named_section (NULL, ".tm_clone_table", 3);
5823 /* Helper comparison function for qsorting by the DECL_UID stored in
5824 alias_pair->emitted_diags. */
5826 static int
5827 tm_alias_pair_cmp (const void *x, const void *y)
5829 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
5830 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
5831 if (p1->uid < p2->uid)
5832 return -1;
5833 if (p1->uid > p2->uid)
5834 return 1;
5835 return 0;
5838 void
5839 finish_tm_clone_pairs (void)
5841 vec<tm_alias_pair> tm_alias_pairs = vNULL;
5843 if (tm_clone_hash == NULL)
5844 return;
5846 /* We need a determenistic order for the .tm_clone_table, otherwise
5847 we will get bootstrap comparison failures, so dump the hash table
5848 to a vector, sort it, and dump the vector. */
5850 /* Dump the hashtable to a vector. */
5851 htab_traverse_noresize (tm_clone_hash, dump_tm_clone_to_vec,
5852 (void *) &tm_alias_pairs);
5853 /* Sort it. */
5854 tm_alias_pairs.qsort (tm_alias_pair_cmp);
5856 /* Dump it. */
5857 dump_tm_clone_pairs (tm_alias_pairs);
5859 htab_delete (tm_clone_hash);
5860 tm_clone_hash = NULL;
5861 tm_alias_pairs.release ();
5865 /* Emit an assembler directive to set symbol for DECL visibility to
5866 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
5868 void
5869 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
5870 int vis ATTRIBUTE_UNUSED)
5872 #ifdef HAVE_GAS_HIDDEN
5873 static const char * const visibility_types[] = {
5874 NULL, "protected", "hidden", "internal"
5877 const char *name, *type;
5879 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5880 type = visibility_types[vis];
5882 fprintf (asm_out_file, "\t.%s\t", type);
5883 assemble_name (asm_out_file, name);
5884 fprintf (asm_out_file, "\n");
5885 #else
5886 if (!DECL_ARTIFICIAL (decl))
5887 warning (OPT_Wattributes, "visibility attribute not supported "
5888 "in this configuration; ignored");
5889 #endif
5892 /* A helper function to call assemble_visibility when needed for a decl. */
5895 maybe_assemble_visibility (tree decl)
5897 enum symbol_visibility vis = DECL_VISIBILITY (decl);
5899 if (vis != VISIBILITY_DEFAULT)
5901 targetm.asm_out.assemble_visibility (decl, vis);
5902 return 1;
5904 else
5905 return 0;
5908 /* Returns 1 if the target configuration supports defining public symbols
5909 so that one of them will be chosen at link time instead of generating a
5910 multiply-defined symbol error, whether through the use of weak symbols or
5911 a target-specific mechanism for having duplicates discarded. */
5914 supports_one_only (void)
5916 if (SUPPORTS_ONE_ONLY)
5917 return 1;
5918 return TARGET_SUPPORTS_WEAK;
5921 /* Set up DECL as a public symbol that can be defined in multiple
5922 translation units without generating a linker error. */
5924 void
5925 make_decl_one_only (tree decl, tree comdat_group)
5927 gcc_assert (TREE_CODE (decl) == VAR_DECL
5928 || TREE_CODE (decl) == FUNCTION_DECL);
5930 TREE_PUBLIC (decl) = 1;
5932 if (SUPPORTS_ONE_ONLY)
5934 #ifdef MAKE_DECL_ONE_ONLY
5935 MAKE_DECL_ONE_ONLY (decl);
5936 #endif
5937 DECL_COMDAT_GROUP (decl) = comdat_group;
5939 else if (TREE_CODE (decl) == VAR_DECL
5940 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node))
5941 DECL_COMMON (decl) = 1;
5942 else
5944 gcc_assert (TARGET_SUPPORTS_WEAK);
5945 DECL_WEAK (decl) = 1;
5949 void
5950 init_varasm_once (void)
5952 section_htab = htab_create_ggc (31, section_entry_hash,
5953 section_entry_eq, NULL);
5954 object_block_htab = htab_create_ggc (31, object_block_entry_hash,
5955 object_block_entry_eq, NULL);
5956 const_desc_htab = htab_create_ggc (1009, const_desc_hash,
5957 const_desc_eq, NULL);
5959 const_alias_set = new_alias_set ();
5960 shared_constant_pool = create_constant_pool ();
5962 #ifdef TEXT_SECTION_ASM_OP
5963 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
5964 TEXT_SECTION_ASM_OP);
5965 #endif
5967 #ifdef DATA_SECTION_ASM_OP
5968 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5969 DATA_SECTION_ASM_OP);
5970 #endif
5972 #ifdef SDATA_SECTION_ASM_OP
5973 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5974 SDATA_SECTION_ASM_OP);
5975 #endif
5977 #ifdef READONLY_DATA_SECTION_ASM_OP
5978 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
5979 READONLY_DATA_SECTION_ASM_OP);
5980 #endif
5982 #ifdef CTORS_SECTION_ASM_OP
5983 ctors_section = get_unnamed_section (0, output_section_asm_op,
5984 CTORS_SECTION_ASM_OP);
5985 #endif
5987 #ifdef DTORS_SECTION_ASM_OP
5988 dtors_section = get_unnamed_section (0, output_section_asm_op,
5989 DTORS_SECTION_ASM_OP);
5990 #endif
5992 #ifdef BSS_SECTION_ASM_OP
5993 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5994 output_section_asm_op,
5995 BSS_SECTION_ASM_OP);
5996 #endif
5998 #ifdef SBSS_SECTION_ASM_OP
5999 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6000 output_section_asm_op,
6001 SBSS_SECTION_ASM_OP);
6002 #endif
6004 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6005 | SECTION_COMMON, emit_tls_common);
6006 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6007 | SECTION_COMMON, emit_local);
6008 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6009 | SECTION_COMMON, emit_common);
6011 #if defined ASM_OUTPUT_ALIGNED_BSS
6012 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
6013 emit_bss);
6014 #endif
6016 targetm.asm_out.init_sections ();
6018 if (readonly_data_section == NULL)
6019 readonly_data_section = text_section;
6021 #ifdef ASM_OUTPUT_EXTERNAL
6022 pending_assemble_externals_set = pointer_set_create ();
6023 #endif
6026 enum tls_model
6027 decl_default_tls_model (const_tree decl)
6029 enum tls_model kind;
6030 bool is_local;
6032 is_local = targetm.binds_local_p (decl);
6033 if (!flag_shlib)
6035 if (is_local)
6036 kind = TLS_MODEL_LOCAL_EXEC;
6037 else
6038 kind = TLS_MODEL_INITIAL_EXEC;
6041 /* Local dynamic is inefficient when we're not combining the
6042 parts of the address. */
6043 else if (optimize && is_local)
6044 kind = TLS_MODEL_LOCAL_DYNAMIC;
6045 else
6046 kind = TLS_MODEL_GLOBAL_DYNAMIC;
6047 if (kind < flag_tls_default)
6048 kind = flag_tls_default;
6050 return kind;
6053 /* Select a set of attributes for section NAME based on the properties
6054 of DECL and whether or not RELOC indicates that DECL's initializer
6055 might contain runtime relocations.
6057 We make the section read-only and executable for a function decl,
6058 read-only for a const data decl, and writable for a non-const data decl. */
6060 unsigned int
6061 default_section_type_flags (tree decl, const char *name, int reloc)
6063 unsigned int flags;
6065 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6066 flags = SECTION_CODE;
6067 else if (decl)
6069 enum section_category category
6070 = categorize_decl_for_section (decl, reloc);
6071 if (decl_readonly_section_1 (category))
6072 flags = 0;
6073 else if (category == SECCAT_DATA_REL_RO
6074 || category == SECCAT_DATA_REL_RO_LOCAL)
6075 flags = SECTION_WRITE | SECTION_RELRO;
6076 else
6077 flags = SECTION_WRITE;
6079 else
6081 flags = SECTION_WRITE;
6082 if (strcmp (name, ".data.rel.ro") == 0
6083 || strcmp (name, ".data.rel.ro.local") == 0)
6084 flags |= SECTION_RELRO;
6087 if (decl && DECL_P (decl) && DECL_ONE_ONLY (decl))
6088 flags |= SECTION_LINKONCE;
6090 if (strcmp (name, ".vtable_map_vars") == 0)
6091 flags |= SECTION_LINKONCE;
6093 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6094 flags |= SECTION_TLS | SECTION_WRITE;
6096 if (strcmp (name, ".bss") == 0
6097 || strncmp (name, ".bss.", 5) == 0
6098 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6099 || strcmp (name, ".sbss") == 0
6100 || strncmp (name, ".sbss.", 6) == 0
6101 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6102 flags |= SECTION_BSS;
6104 if (strcmp (name, ".tdata") == 0
6105 || strncmp (name, ".tdata.", 7) == 0
6106 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6107 flags |= SECTION_TLS;
6109 if (strcmp (name, ".tbss") == 0
6110 || strncmp (name, ".tbss.", 6) == 0
6111 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6112 flags |= SECTION_TLS | SECTION_BSS;
6114 /* These three sections have special ELF types. They are neither
6115 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
6116 want to print a section type (@progbits or @nobits). If someone
6117 is silly enough to emit code or TLS variables to one of these
6118 sections, then don't handle them specially. */
6119 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6120 && (strcmp (name, ".init_array") == 0
6121 || strcmp (name, ".fini_array") == 0
6122 || strcmp (name, ".preinit_array") == 0))
6123 flags |= SECTION_NOTYPE;
6125 return flags;
6128 /* Return true if the target supports some form of global BSS,
6129 either through bss_noswitch_section, or by selecting a BSS
6130 section in TARGET_ASM_SELECT_SECTION. */
6132 bool
6133 have_global_bss_p (void)
6135 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6138 /* Output assembly to switch to section NAME with attribute FLAGS.
6139 Four variants for common object file formats. */
6141 void
6142 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6143 unsigned int flags ATTRIBUTE_UNUSED,
6144 tree decl ATTRIBUTE_UNUSED)
6146 /* Some object formats don't support named sections at all. The
6147 front-end should already have flagged this as an error. */
6148 gcc_unreachable ();
6151 #ifndef TLS_SECTION_ASM_FLAG
6152 #define TLS_SECTION_ASM_FLAG 'T'
6153 #endif
6155 void
6156 default_elf_asm_named_section (const char *name, unsigned int flags,
6157 tree decl ATTRIBUTE_UNUSED)
6159 char flagchars[10], *f = flagchars;
6161 /* If we have already declared this section, we can use an
6162 abbreviated form to switch back to it -- unless this section is
6163 part of a COMDAT groups, in which case GAS requires the full
6164 declaration every time. */
6165 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6166 && (flags & SECTION_DECLARED))
6168 fprintf (asm_out_file, "\t.section\t%s\n", name);
6169 return;
6172 if (!(flags & SECTION_DEBUG))
6173 *f++ = 'a';
6174 if (flags & SECTION_EXCLUDE)
6175 *f++ = 'e';
6176 if (flags & SECTION_WRITE)
6177 *f++ = 'w';
6178 if (flags & SECTION_CODE)
6179 *f++ = 'x';
6180 if (flags & SECTION_SMALL)
6181 *f++ = 's';
6182 if (flags & SECTION_MERGE)
6183 *f++ = 'M';
6184 if (flags & SECTION_STRINGS)
6185 *f++ = 'S';
6186 if (flags & SECTION_TLS)
6187 *f++ = TLS_SECTION_ASM_FLAG;
6188 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6189 *f++ = 'G';
6190 *f = '\0';
6192 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6194 if (!(flags & SECTION_NOTYPE))
6196 const char *type;
6197 const char *format;
6199 if (flags & SECTION_BSS)
6200 type = "nobits";
6201 else
6202 type = "progbits";
6204 format = ",@%s";
6205 /* On platforms that use "@" as the assembly comment character,
6206 use "%" instead. */
6207 if (strcmp (ASM_COMMENT_START, "@") == 0)
6208 format = ",%%%s";
6209 fprintf (asm_out_file, format, type);
6211 if (flags & SECTION_ENTSIZE)
6212 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6213 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6215 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6216 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6217 else
6218 fprintf (asm_out_file, ",%s,comdat",
6219 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6223 putc ('\n', asm_out_file);
6226 void
6227 default_coff_asm_named_section (const char *name, unsigned int flags,
6228 tree decl ATTRIBUTE_UNUSED)
6230 char flagchars[8], *f = flagchars;
6232 if (flags & SECTION_WRITE)
6233 *f++ = 'w';
6234 if (flags & SECTION_CODE)
6235 *f++ = 'x';
6236 *f = '\0';
6238 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6241 void
6242 default_pe_asm_named_section (const char *name, unsigned int flags,
6243 tree decl)
6245 default_coff_asm_named_section (name, flags, decl);
6247 if (flags & SECTION_LINKONCE)
6249 /* Functions may have been compiled at various levels of
6250 optimization so we can't use `same_size' here.
6251 Instead, have the linker pick one. */
6252 fprintf (asm_out_file, "\t.linkonce %s\n",
6253 (flags & SECTION_CODE ? "discard" : "same_size"));
6257 /* The lame default section selector. */
6259 section *
6260 default_select_section (tree decl, int reloc,
6261 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6263 if (DECL_P (decl))
6265 if (decl_readonly_section (decl, reloc))
6266 return readonly_data_section;
6268 else if (TREE_CODE (decl) == CONSTRUCTOR)
6270 if (! ((flag_pic && reloc)
6271 || !TREE_READONLY (decl)
6272 || TREE_SIDE_EFFECTS (decl)
6273 || !TREE_CONSTANT (decl)))
6274 return readonly_data_section;
6276 else if (TREE_CODE (decl) == STRING_CST)
6277 return readonly_data_section;
6278 else if (! (flag_pic && reloc))
6279 return readonly_data_section;
6281 return data_section;
6284 enum section_category
6285 categorize_decl_for_section (const_tree decl, int reloc)
6287 enum section_category ret;
6289 if (TREE_CODE (decl) == FUNCTION_DECL)
6290 return SECCAT_TEXT;
6291 else if (TREE_CODE (decl) == STRING_CST)
6293 if (flag_mudflap
6294 || (flag_asan && asan_protect_global (CONST_CAST_TREE (decl))))
6295 /* or !flag_merge_constants */
6296 return SECCAT_RODATA;
6297 else
6298 return SECCAT_RODATA_MERGE_STR;
6300 else if (TREE_CODE (decl) == VAR_DECL)
6302 if (bss_initializer_p (decl))
6303 ret = SECCAT_BSS;
6304 else if (! TREE_READONLY (decl)
6305 || TREE_SIDE_EFFECTS (decl)
6306 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
6308 /* Here the reloc_rw_mask is not testing whether the section should
6309 be read-only or not, but whether the dynamic link will have to
6310 do something. If so, we wish to segregate the data in order to
6311 minimize cache misses inside the dynamic linker. */
6312 if (reloc & targetm.asm_out.reloc_rw_mask ())
6313 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6314 else
6315 ret = SECCAT_DATA;
6317 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6318 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6319 else if (reloc || flag_merge_constants < 2 || flag_mudflap
6320 || (flag_asan && asan_protect_global (CONST_CAST_TREE (decl))))
6321 /* C and C++ don't allow different variables to share the same
6322 location. -fmerge-all-constants allows even that (at the
6323 expense of not conforming). */
6324 ret = SECCAT_RODATA;
6325 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6326 ret = SECCAT_RODATA_MERGE_STR_INIT;
6327 else
6328 ret = SECCAT_RODATA_MERGE_CONST;
6330 else if (TREE_CODE (decl) == CONSTRUCTOR)
6332 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6333 || TREE_SIDE_EFFECTS (decl)
6334 || ! TREE_CONSTANT (decl))
6335 ret = SECCAT_DATA;
6336 else
6337 ret = SECCAT_RODATA;
6339 else
6340 ret = SECCAT_RODATA;
6342 /* There are no read-only thread-local sections. */
6343 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6345 /* Note that this would be *just* SECCAT_BSS, except that there's
6346 no concept of a read-only thread-local-data section. */
6347 if (ret == SECCAT_BSS
6348 || (flag_zero_initialized_in_bss
6349 && initializer_zerop (DECL_INITIAL (decl))))
6350 ret = SECCAT_TBSS;
6351 else
6352 ret = SECCAT_TDATA;
6355 /* If the target uses small data sections, select it. */
6356 else if (targetm.in_small_data_p (decl))
6358 if (ret == SECCAT_BSS)
6359 ret = SECCAT_SBSS;
6360 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6361 ret = SECCAT_SRODATA;
6362 else
6363 ret = SECCAT_SDATA;
6366 return ret;
6369 static bool
6370 decl_readonly_section_1 (enum section_category category)
6372 switch (category)
6374 case SECCAT_RODATA:
6375 case SECCAT_RODATA_MERGE_STR:
6376 case SECCAT_RODATA_MERGE_STR_INIT:
6377 case SECCAT_RODATA_MERGE_CONST:
6378 case SECCAT_SRODATA:
6379 return true;
6380 default:
6381 return false;
6385 bool
6386 decl_readonly_section (const_tree decl, int reloc)
6388 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6391 /* Select a section based on the above categorization. */
6393 section *
6394 default_elf_select_section (tree decl, int reloc,
6395 unsigned HOST_WIDE_INT align)
6397 const char *sname;
6398 switch (categorize_decl_for_section (decl, reloc))
6400 case SECCAT_TEXT:
6401 /* We're not supposed to be called on FUNCTION_DECLs. */
6402 gcc_unreachable ();
6403 case SECCAT_RODATA:
6404 return readonly_data_section;
6405 case SECCAT_RODATA_MERGE_STR:
6406 return mergeable_string_section (decl, align, 0);
6407 case SECCAT_RODATA_MERGE_STR_INIT:
6408 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6409 case SECCAT_RODATA_MERGE_CONST:
6410 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6411 case SECCAT_SRODATA:
6412 sname = ".sdata2";
6413 break;
6414 case SECCAT_DATA:
6415 return data_section;
6416 case SECCAT_DATA_REL:
6417 sname = ".data.rel";
6418 break;
6419 case SECCAT_DATA_REL_LOCAL:
6420 sname = ".data.rel.local";
6421 break;
6422 case SECCAT_DATA_REL_RO:
6423 sname = ".data.rel.ro";
6424 break;
6425 case SECCAT_DATA_REL_RO_LOCAL:
6426 sname = ".data.rel.ro.local";
6427 break;
6428 case SECCAT_SDATA:
6429 sname = ".sdata";
6430 break;
6431 case SECCAT_TDATA:
6432 sname = ".tdata";
6433 break;
6434 case SECCAT_BSS:
6435 if (bss_section)
6436 return bss_section;
6437 sname = ".bss";
6438 break;
6439 case SECCAT_SBSS:
6440 sname = ".sbss";
6441 break;
6442 case SECCAT_TBSS:
6443 sname = ".tbss";
6444 break;
6445 default:
6446 gcc_unreachable ();
6449 return get_named_section (decl, sname, reloc);
6452 /* Construct a unique section name based on the decl name and the
6453 categorization performed above. */
6455 void
6456 default_unique_section (tree decl, int reloc)
6458 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6459 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6460 const char *prefix, *name, *linkonce;
6461 char *string;
6463 switch (categorize_decl_for_section (decl, reloc))
6465 case SECCAT_TEXT:
6466 prefix = one_only ? ".t" : ".text";
6467 break;
6468 case SECCAT_RODATA:
6469 case SECCAT_RODATA_MERGE_STR:
6470 case SECCAT_RODATA_MERGE_STR_INIT:
6471 case SECCAT_RODATA_MERGE_CONST:
6472 prefix = one_only ? ".r" : ".rodata";
6473 break;
6474 case SECCAT_SRODATA:
6475 prefix = one_only ? ".s2" : ".sdata2";
6476 break;
6477 case SECCAT_DATA:
6478 prefix = one_only ? ".d" : ".data";
6479 break;
6480 case SECCAT_DATA_REL:
6481 prefix = one_only ? ".d.rel" : ".data.rel";
6482 break;
6483 case SECCAT_DATA_REL_LOCAL:
6484 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6485 break;
6486 case SECCAT_DATA_REL_RO:
6487 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6488 break;
6489 case SECCAT_DATA_REL_RO_LOCAL:
6490 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6491 break;
6492 case SECCAT_SDATA:
6493 prefix = one_only ? ".s" : ".sdata";
6494 break;
6495 case SECCAT_BSS:
6496 prefix = one_only ? ".b" : ".bss";
6497 break;
6498 case SECCAT_SBSS:
6499 prefix = one_only ? ".sb" : ".sbss";
6500 break;
6501 case SECCAT_TDATA:
6502 prefix = one_only ? ".td" : ".tdata";
6503 break;
6504 case SECCAT_TBSS:
6505 prefix = one_only ? ".tb" : ".tbss";
6506 break;
6507 default:
6508 gcc_unreachable ();
6511 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
6512 name = targetm.strip_name_encoding (name);
6514 /* If we're using one_only, then there needs to be a .gnu.linkonce
6515 prefix to the section name. */
6516 linkonce = one_only ? ".gnu.linkonce" : "";
6518 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6520 DECL_SECTION_NAME (decl) = build_string (strlen (string), string);
6523 /* Like compute_reloc_for_constant, except for an RTX. The return value
6524 is a mask for which bit 1 indicates a global relocation, and bit 0
6525 indicates a local relocation. */
6527 static int
6528 compute_reloc_for_rtx_1 (rtx *xp, void *data)
6530 int *preloc = (int *) data;
6531 rtx x = *xp;
6533 switch (GET_CODE (x))
6535 case SYMBOL_REF:
6536 *preloc |= SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6537 break;
6538 case LABEL_REF:
6539 *preloc |= 1;
6540 break;
6541 default:
6542 break;
6545 return 0;
6548 static int
6549 compute_reloc_for_rtx (rtx x)
6551 int reloc;
6553 switch (GET_CODE (x))
6555 case CONST:
6556 case SYMBOL_REF:
6557 case LABEL_REF:
6558 reloc = 0;
6559 for_each_rtx (&x, compute_reloc_for_rtx_1, &reloc);
6560 return reloc;
6562 default:
6563 return 0;
6567 section *
6568 default_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
6569 rtx x,
6570 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6572 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6573 return data_section;
6574 else
6575 return readonly_data_section;
6578 section *
6579 default_elf_select_rtx_section (enum machine_mode mode, rtx x,
6580 unsigned HOST_WIDE_INT align)
6582 int reloc = compute_reloc_for_rtx (x);
6584 /* ??? Handle small data here somehow. */
6586 if (reloc & targetm.asm_out.reloc_rw_mask ())
6588 if (reloc == 1)
6589 return get_named_section (NULL, ".data.rel.ro.local", 1);
6590 else
6591 return get_named_section (NULL, ".data.rel.ro", 3);
6594 return mergeable_constant_section (mode, align, 0);
6597 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6599 void
6600 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6602 rtx symbol;
6603 int flags;
6605 /* Careful not to prod global register variables. */
6606 if (!MEM_P (rtl))
6607 return;
6608 symbol = XEXP (rtl, 0);
6609 if (GET_CODE (symbol) != SYMBOL_REF)
6610 return;
6612 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6613 if (TREE_CODE (decl) == FUNCTION_DECL)
6614 flags |= SYMBOL_FLAG_FUNCTION;
6615 if (targetm.binds_local_p (decl))
6616 flags |= SYMBOL_FLAG_LOCAL;
6617 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6618 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6619 else if (targetm.in_small_data_p (decl))
6620 flags |= SYMBOL_FLAG_SMALL;
6621 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6622 being PUBLIC, the thing *must* be defined in this translation unit.
6623 Prevent this buglet from being propagated into rtl code as well. */
6624 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6625 flags |= SYMBOL_FLAG_EXTERNAL;
6627 SYMBOL_REF_FLAGS (symbol) = flags;
6630 /* By default, we do nothing for encode_section_info, so we need not
6631 do anything but discard the '*' marker. */
6633 const char *
6634 default_strip_name_encoding (const char *str)
6636 return str + (*str == '*');
6639 #ifdef ASM_OUTPUT_DEF
6640 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6641 anchor relative to ".", the current section position. */
6643 void
6644 default_asm_output_anchor (rtx symbol)
6646 char buffer[100];
6648 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6649 SYMBOL_REF_BLOCK_OFFSET (symbol));
6650 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6652 #endif
6654 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6656 bool
6657 default_use_anchors_for_symbol_p (const_rtx symbol)
6659 section *sect;
6660 tree decl;
6662 /* Don't use anchors for mergeable sections. The linker might move
6663 the objects around. */
6664 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6665 if (sect->common.flags & SECTION_MERGE)
6666 return false;
6668 /* Don't use anchors for small data sections. The small data register
6669 acts as an anchor for such sections. */
6670 if (sect->common.flags & SECTION_SMALL)
6671 return false;
6673 decl = SYMBOL_REF_DECL (symbol);
6674 if (decl && DECL_P (decl))
6676 /* Don't use section anchors for decls that might be defined or
6677 usurped by other modules. */
6678 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6679 return false;
6681 /* Don't use section anchors for decls that will be placed in a
6682 small data section. */
6683 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6684 one above. The problem is that we only use SECTION_SMALL for
6685 sections that should be marked as small in the section directive. */
6686 if (targetm.in_small_data_p (decl))
6687 return false;
6689 return true;
6692 /* Return true when RESOLUTION indicate that symbol will be bound to the
6693 definition provided by current .o file. */
6695 static bool
6696 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
6698 return (resolution == LDPR_PREVAILING_DEF
6699 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6700 || resolution == LDPR_PREVAILING_DEF_IRONLY);
6703 /* Return true when RESOLUTION indicate that symbol will be bound locally
6704 within current executable or DSO. */
6706 static bool
6707 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
6709 return (resolution == LDPR_PREVAILING_DEF
6710 || resolution == LDPR_PREVAILING_DEF_IRONLY
6711 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6712 || resolution == LDPR_PREEMPTED_REG
6713 || resolution == LDPR_PREEMPTED_IR
6714 || resolution == LDPR_RESOLVED_IR
6715 || resolution == LDPR_RESOLVED_EXEC);
6718 /* Assume ELF-ish defaults, since that's pretty much the most liberal
6719 wrt cross-module name binding. */
6721 bool
6722 default_binds_local_p (const_tree exp)
6724 return default_binds_local_p_1 (exp, flag_shlib);
6727 bool
6728 default_binds_local_p_1 (const_tree exp, int shlib)
6730 bool local_p;
6731 bool resolved_locally = false;
6732 bool resolved_to_local_def = false;
6734 /* With resolution file in hands, take look into resolutions.
6735 We can't just return true for resolved_locally symbols,
6736 because dynamic linking might overwrite symbols
6737 in shared libraries. */
6738 if (TREE_CODE (exp) == VAR_DECL && TREE_PUBLIC (exp)
6739 && (TREE_STATIC (exp) || DECL_EXTERNAL (exp)))
6741 struct varpool_node *vnode = varpool_get_node (exp);
6742 if (vnode && resolution_local_p (vnode->symbol.resolution))
6743 resolved_locally = true;
6744 if (vnode
6745 && resolution_to_local_definition_p (vnode->symbol.resolution))
6746 resolved_to_local_def = true;
6748 else if (TREE_CODE (exp) == FUNCTION_DECL && TREE_PUBLIC (exp))
6750 struct cgraph_node *node = cgraph_get_node (exp);
6751 if (node
6752 && resolution_local_p (node->symbol.resolution))
6753 resolved_locally = true;
6754 if (node
6755 && resolution_to_local_definition_p (node->symbol.resolution))
6756 resolved_to_local_def = true;
6759 /* A non-decl is an entry in the constant pool. */
6760 if (!DECL_P (exp))
6761 local_p = true;
6762 /* Weakrefs may not bind locally, even though the weakref itself is always
6763 static and therefore local. Similarly, the resolver for ifunc functions
6764 might resolve to a non-local function.
6765 FIXME: We can resolve the weakref case more curefuly by looking at the
6766 weakref alias. */
6767 else if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
6768 || (TREE_CODE (exp) == FUNCTION_DECL
6769 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
6770 local_p = false;
6771 /* Static variables are always local. */
6772 else if (! TREE_PUBLIC (exp))
6773 local_p = true;
6774 /* A variable is local if the user has said explicitly that it will
6775 be. */
6776 else if ((DECL_VISIBILITY_SPECIFIED (exp)
6777 || resolved_to_local_def)
6778 && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6779 local_p = true;
6780 /* Variables defined outside this object might not be local. */
6781 else if (DECL_EXTERNAL (exp) && !resolved_locally)
6782 local_p = false;
6783 /* If defined in this object and visibility is not default, must be
6784 local. */
6785 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6786 local_p = true;
6787 /* Default visibility weak data can be overridden by a strong symbol
6788 in another module and so are not local. */
6789 else if (DECL_WEAK (exp)
6790 && !resolved_locally)
6791 local_p = false;
6792 /* If PIC, then assume that any global name can be overridden by
6793 symbols resolved from other modules. */
6794 else if (shlib)
6795 local_p = false;
6796 /* Uninitialized COMMON variable may be unified with symbols
6797 resolved from other modules. */
6798 else if (DECL_COMMON (exp)
6799 && !resolved_locally
6800 && (DECL_INITIAL (exp) == NULL
6801 || DECL_INITIAL (exp) == error_mark_node))
6802 local_p = false;
6803 /* Otherwise we're left with initialized (or non-common) global data
6804 which is of necessity defined locally. */
6805 else
6806 local_p = true;
6808 return local_p;
6811 /* Return true when references to DECL must bind to current definition in
6812 final executable.
6814 The condition is usually equivalent to whether the function binds to the
6815 current module (shared library or executable), that is to binds_local_p.
6816 We use this fact to avoid need for another target hook and implement
6817 the logic using binds_local_p and just special cases where
6818 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
6819 the weak definitions (that can be overwritten at linktime by other
6820 definition from different object file) and when resolution info is available
6821 we simply use the knowledge passed to us by linker plugin. */
6822 bool
6823 decl_binds_to_current_def_p (tree decl)
6825 gcc_assert (DECL_P (decl));
6826 if (!targetm.binds_local_p (decl))
6827 return false;
6828 if (!TREE_PUBLIC (decl))
6829 return true;
6830 /* When resolution is available, just use it. */
6831 if (TREE_CODE (decl) == VAR_DECL
6832 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl)))
6834 struct varpool_node *vnode = varpool_get_node (decl);
6835 if (vnode
6836 && vnode->symbol.resolution != LDPR_UNKNOWN)
6837 return resolution_to_local_definition_p (vnode->symbol.resolution);
6839 else if (TREE_CODE (decl) == FUNCTION_DECL)
6841 struct cgraph_node *node = cgraph_get_node (decl);
6842 if (node
6843 && node->symbol.resolution != LDPR_UNKNOWN)
6844 return resolution_to_local_definition_p (node->symbol.resolution);
6846 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
6847 binds locally but still can be overwritten), DECL_COMMON (can be merged
6848 with a non-common definition somewhere in the same module) or
6849 DECL_EXTERNAL.
6850 This rely on fact that binds_local_p behave as decl_replaceable_p
6851 for all other declaration types. */
6852 if (DECL_WEAK (decl))
6853 return false;
6854 if (DECL_COMMON (decl)
6855 && (DECL_INITIAL (decl) == NULL
6856 || DECL_INITIAL (decl) == error_mark_node))
6857 return false;
6858 if (DECL_EXTERNAL (decl))
6859 return false;
6860 return true;
6863 /* A replaceable function or variable is one which may be replaced
6864 at link-time with an entirely different definition, provided that the
6865 replacement has the same type. For example, functions declared
6866 with __attribute__((weak)) on most systems are replaceable.
6868 COMDAT functions are not replaceable, since all definitions of the
6869 function must be equivalent. It is important that COMDAT functions
6870 not be treated as replaceable so that use of C++ template
6871 instantiations is not penalized. */
6873 bool
6874 decl_replaceable_p (tree decl)
6876 gcc_assert (DECL_P (decl));
6877 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
6878 return false;
6879 return !decl_binds_to_current_def_p (decl);
6882 /* Default function to output code that will globalize a label. A
6883 target must define GLOBAL_ASM_OP or provide its own function to
6884 globalize a label. */
6885 #ifdef GLOBAL_ASM_OP
6886 void
6887 default_globalize_label (FILE * stream, const char *name)
6889 fputs (GLOBAL_ASM_OP, stream);
6890 assemble_name (stream, name);
6891 putc ('\n', stream);
6893 #endif /* GLOBAL_ASM_OP */
6895 /* Default function to output code that will globalize a declaration. */
6896 void
6897 default_globalize_decl_name (FILE * stream, tree decl)
6899 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
6900 targetm.asm_out.globalize_label (stream, name);
6903 /* Default function to output a label for unwind information. The
6904 default is to do nothing. A target that needs nonlocal labels for
6905 unwind information must provide its own function to do this. */
6906 void
6907 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
6908 tree decl ATTRIBUTE_UNUSED,
6909 int for_eh ATTRIBUTE_UNUSED,
6910 int empty ATTRIBUTE_UNUSED)
6914 /* Default function to output a label to divide up the exception table.
6915 The default is to do nothing. A target that needs/wants to divide
6916 up the table must provide it's own function to do this. */
6917 void
6918 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
6922 /* This is how to output an internal numbered label where PREFIX is
6923 the class of label and LABELNO is the number within the class. */
6925 void
6926 default_generate_internal_label (char *buf, const char *prefix,
6927 unsigned long labelno)
6929 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6932 /* This is how to output an internal numbered label where PREFIX is
6933 the class of label and LABELNO is the number within the class. */
6935 void
6936 default_internal_label (FILE *stream, const char *prefix,
6937 unsigned long labelno)
6939 char *const buf = (char *) alloca (40 + strlen (prefix));
6940 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6941 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
6945 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
6947 void
6948 default_asm_declare_constant_name (FILE *file, const char *name,
6949 const_tree exp ATTRIBUTE_UNUSED,
6950 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
6952 assemble_label (file, name);
6955 /* This is the default behavior at the beginning of a file. It's
6956 controlled by two other target-hook toggles. */
6957 void
6958 default_file_start (void)
6960 if (targetm.asm_file_start_app_off
6961 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
6962 fputs (ASM_APP_OFF, asm_out_file);
6964 if (targetm.asm_file_start_file_directive)
6965 output_file_directive (asm_out_file, main_input_filename);
6968 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
6969 which emits a special section directive used to indicate whether or
6970 not this object file needs an executable stack. This is primarily
6971 a GNU extension to ELF but could be used on other targets. */
6973 int trampolines_created;
6975 void
6976 file_end_indicate_exec_stack (void)
6978 unsigned int flags = SECTION_DEBUG;
6979 if (trampolines_created)
6980 flags |= SECTION_CODE;
6982 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
6985 /* Emit a special section directive to indicate that this object file
6986 was compiled with -fsplit-stack. This is used to let the linker
6987 detect calls between split-stack code and non-split-stack code, so
6988 that it can modify the split-stack code to allocate a sufficiently
6989 large stack. We emit another special section if there are any
6990 functions in this file which have the no_split_stack attribute, to
6991 prevent the linker from warning about being unable to convert the
6992 functions if they call non-split-stack code. */
6994 void
6995 file_end_indicate_split_stack (void)
6997 if (flag_split_stack)
6999 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
7000 NULL));
7001 if (saw_no_split_stack)
7002 switch_to_section (get_section (".note.GNU-no-split-stack",
7003 SECTION_DEBUG, NULL));
7007 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
7008 a get_unnamed_section callback. */
7010 void
7011 output_section_asm_op (const void *directive)
7013 fprintf (asm_out_file, "%s\n", (const char *) directive);
7016 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
7017 the current section is NEW_SECTION. */
7019 void
7020 switch_to_section (section *new_section)
7022 if (in_section == new_section)
7023 return;
7025 if (new_section->common.flags & SECTION_FORGET)
7026 in_section = NULL;
7027 else
7028 in_section = new_section;
7030 switch (SECTION_STYLE (new_section))
7032 case SECTION_NAMED:
7033 targetm.asm_out.named_section (new_section->named.name,
7034 new_section->named.common.flags,
7035 new_section->named.decl);
7036 break;
7038 case SECTION_UNNAMED:
7039 new_section->unnamed.callback (new_section->unnamed.data);
7040 break;
7042 case SECTION_NOSWITCH:
7043 gcc_unreachable ();
7044 break;
7047 new_section->common.flags |= SECTION_DECLARED;
7050 /* If block symbol SYMBOL has not yet been assigned an offset, place
7051 it at the end of its block. */
7053 void
7054 place_block_symbol (rtx symbol)
7056 unsigned HOST_WIDE_INT size, mask, offset;
7057 struct constant_descriptor_rtx *desc;
7058 unsigned int alignment;
7059 struct object_block *block;
7060 tree decl;
7062 gcc_assert (SYMBOL_REF_BLOCK (symbol));
7063 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7064 return;
7066 /* Work out the symbol's size and alignment. */
7067 if (CONSTANT_POOL_ADDRESS_P (symbol))
7069 desc = SYMBOL_REF_CONSTANT (symbol);
7070 alignment = desc->align;
7071 size = GET_MODE_SIZE (desc->mode);
7073 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7075 decl = SYMBOL_REF_DECL (symbol);
7076 alignment = DECL_ALIGN (decl);
7077 size = get_constant_size (DECL_INITIAL (decl));
7078 if (flag_asan
7079 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7080 && asan_protect_global (DECL_INITIAL (decl)))
7081 size += asan_red_zone_size (size);
7083 else
7085 decl = SYMBOL_REF_DECL (symbol);
7086 alignment = get_variable_align (decl);
7087 size = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
7088 if (flag_asan && asan_protect_global (decl))
7090 size += asan_red_zone_size (size);
7091 alignment = MAX (alignment,
7092 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7096 /* Calculate the object's offset from the start of the block. */
7097 block = SYMBOL_REF_BLOCK (symbol);
7098 mask = alignment / BITS_PER_UNIT - 1;
7099 offset = (block->size + mask) & ~mask;
7100 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7102 /* Record the block's new alignment and size. */
7103 block->alignment = MAX (block->alignment, alignment);
7104 block->size = offset + size;
7106 vec_safe_push (block->objects, symbol);
7109 /* Return the anchor that should be used to address byte offset OFFSET
7110 from the first object in BLOCK. MODEL is the TLS model used
7111 to access it. */
7114 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7115 enum tls_model model)
7117 char label[100];
7118 unsigned int begin, middle, end;
7119 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7120 rtx anchor;
7122 /* Work out the anchor's offset. Use an offset of 0 for the first
7123 anchor so that we don't pessimize the case where we take the address
7124 of a variable at the beginning of the block. This is particularly
7125 useful when a block has only one variable assigned to it.
7127 We try to place anchors RANGE bytes apart, so there can then be
7128 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7129 a ptr_mode offset. With some target settings, the lowest such
7130 anchor might be out of range for the lowest ptr_mode offset;
7131 likewise the highest anchor for the highest offset. Use anchors
7132 at the extreme ends of the ptr_mode range in such cases.
7134 All arithmetic uses unsigned integers in order to avoid
7135 signed overflow. */
7136 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7137 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7138 range = max_offset - min_offset + 1;
7139 if (range == 0)
7140 offset = 0;
7141 else
7143 bias = 1 << (GET_MODE_BITSIZE (ptr_mode) - 1);
7144 if (offset < 0)
7146 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7147 delta -= delta % range;
7148 if (delta > bias)
7149 delta = bias;
7150 offset = (HOST_WIDE_INT) (-delta);
7152 else
7154 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7155 delta -= delta % range;
7156 if (delta > bias - 1)
7157 delta = bias - 1;
7158 offset = (HOST_WIDE_INT) delta;
7162 /* Do a binary search to see if there's already an anchor we can use.
7163 Set BEGIN to the new anchor's index if not. */
7164 begin = 0;
7165 end = vec_safe_length (block->anchors);
7166 while (begin != end)
7168 middle = (end + begin) / 2;
7169 anchor = (*block->anchors)[middle];
7170 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7171 end = middle;
7172 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7173 begin = middle + 1;
7174 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7175 end = middle;
7176 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7177 begin = middle + 1;
7178 else
7179 return anchor;
7182 /* Create a new anchor with a unique label. */
7183 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7184 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7185 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7186 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7188 /* Insert it at index BEGIN. */
7189 vec_safe_insert (block->anchors, begin, anchor);
7190 return anchor;
7193 /* Output the objects in BLOCK. */
7195 static void
7196 output_object_block (struct object_block *block)
7198 struct constant_descriptor_rtx *desc;
7199 unsigned int i;
7200 HOST_WIDE_INT offset;
7201 tree decl;
7202 rtx symbol;
7204 if (!block->objects)
7205 return;
7207 /* Switch to the section and make sure that the first byte is
7208 suitably aligned. */
7209 switch_to_section (block->sect);
7210 assemble_align (block->alignment);
7212 /* Define the values of all anchors relative to the current section
7213 position. */
7214 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7215 targetm.asm_out.output_anchor (symbol);
7217 /* Output the objects themselves. */
7218 offset = 0;
7219 FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7221 /* Move to the object's offset, padding with zeros if necessary. */
7222 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7223 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7224 if (CONSTANT_POOL_ADDRESS_P (symbol))
7226 desc = SYMBOL_REF_CONSTANT (symbol);
7227 output_constant_pool_1 (desc, 1);
7228 offset += GET_MODE_SIZE (desc->mode);
7230 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7232 HOST_WIDE_INT size;
7233 decl = SYMBOL_REF_DECL (symbol);
7234 assemble_constant_contents (DECL_INITIAL (decl), XSTR (symbol, 0),
7235 DECL_ALIGN (decl));
7236 size = get_constant_size (DECL_INITIAL (decl));
7237 offset += size;
7238 if (flag_asan
7239 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7240 && asan_protect_global (DECL_INITIAL (decl)))
7242 size = asan_red_zone_size (size);
7243 assemble_zeros (size);
7244 offset += size;
7247 else
7249 HOST_WIDE_INT size;
7250 decl = SYMBOL_REF_DECL (symbol);
7251 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7252 size = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
7253 offset += size;
7254 if (flag_asan && asan_protect_global (decl))
7256 size = asan_red_zone_size (size);
7257 assemble_zeros (size);
7258 offset += size;
7264 /* A htab_traverse callback used to call output_object_block for
7265 each member of object_block_htab. */
7267 static int
7268 output_object_block_htab (void **slot, void *data ATTRIBUTE_UNUSED)
7270 output_object_block ((struct object_block *) (*slot));
7271 return 1;
7274 /* Output the definitions of all object_blocks. */
7276 void
7277 output_object_blocks (void)
7279 htab_traverse (object_block_htab, output_object_block_htab, NULL);
7282 /* This function provides a possible implementation of the
7283 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7284 by -frecord-gcc-switches it creates a new mergeable, string section in the
7285 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7286 contains the switches in ASCII format.
7288 FIXME: This code does not correctly handle double quote characters
7289 that appear inside strings, (it strips them rather than preserving them).
7290 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7291 characters - instead it treats them as sub-string separators. Since
7292 we want to emit NUL strings terminators into the object file we have to use
7293 ASM_OUTPUT_SKIP. */
7296 elf_record_gcc_switches (print_switch_type type, const char * name)
7298 switch (type)
7300 case SWITCH_TYPE_PASSED:
7301 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7302 ASM_OUTPUT_SKIP (asm_out_file, (unsigned HOST_WIDE_INT) 1);
7303 break;
7305 case SWITCH_TYPE_DESCRIPTIVE:
7306 if (name == NULL)
7308 /* Distinguish between invocations where name is NULL. */
7309 static bool started = false;
7311 if (!started)
7313 section * sec;
7315 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7316 SECTION_DEBUG
7317 | SECTION_MERGE
7318 | SECTION_STRINGS
7319 | (SECTION_ENTSIZE & 1),
7320 NULL);
7321 switch_to_section (sec);
7322 started = true;
7326 default:
7327 break;
7330 /* The return value is currently ignored by the caller, but must be 0.
7331 For -fverbose-asm the return value would be the number of characters
7332 emitted into the assembler file. */
7333 return 0;
7336 /* Emit text to declare externally defined symbols. It is needed to
7337 properly support non-default visibility. */
7338 void
7339 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7340 tree decl,
7341 const char *name ATTRIBUTE_UNUSED)
7343 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7344 set in order to avoid putting out names that are never really
7345 used. */
7346 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7347 && targetm.binds_local_p (decl))
7348 maybe_assemble_visibility (decl);
7351 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7353 void
7354 default_asm_output_source_filename (FILE *file, const char *name)
7356 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7357 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7358 #else
7359 fprintf (file, "\t.file\t");
7360 output_quoted_string (file, name);
7361 putc ('\n', file);
7362 #endif
7365 /* Output a file name in the form wanted by System V. */
7367 void
7368 output_file_directive (FILE *asm_file, const char *input_name)
7370 int len;
7371 const char *na;
7373 if (input_name == NULL)
7374 input_name = "<stdin>";
7375 else
7376 input_name = remap_debug_filename (input_name);
7378 len = strlen (input_name);
7379 na = input_name + len;
7381 /* NA gets INPUT_NAME sans directory names. */
7382 while (na > input_name)
7384 if (IS_DIR_SEPARATOR (na[-1]))
7385 break;
7386 na--;
7389 targetm.asm_out.output_source_filename (asm_file, na);
7392 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7393 EXP. */
7395 make_debug_expr_from_rtl (const_rtx exp)
7397 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7398 enum machine_mode mode = GET_MODE (exp);
7399 rtx dval;
7401 DECL_ARTIFICIAL (ddecl) = 1;
7402 if (REG_P (exp) && REG_EXPR (exp))
7403 type = TREE_TYPE (REG_EXPR (exp));
7404 else if (MEM_P (exp) && MEM_EXPR (exp))
7405 type = TREE_TYPE (MEM_EXPR (exp));
7406 else
7407 type = NULL_TREE;
7408 if (type && TYPE_MODE (type) == mode)
7409 TREE_TYPE (ddecl) = type;
7410 else
7411 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7412 DECL_MODE (ddecl) = mode;
7413 dval = gen_rtx_DEBUG_EXPR (mode);
7414 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7415 SET_DECL_RTL (ddecl, dval);
7416 return dval;
7419 #ifdef ELF_ASCII_ESCAPES
7420 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7422 void
7423 default_elf_asm_output_limited_string (FILE *f, const char *s)
7425 int escape;
7426 unsigned char c;
7428 fputs (STRING_ASM_OP, f);
7429 putc ('"', f);
7430 while (*s != '\0')
7432 c = *s;
7433 escape = ELF_ASCII_ESCAPES[c];
7434 switch (escape)
7436 case 0:
7437 putc (c, f);
7438 break;
7439 case 1:
7440 /* TODO: Print in hex with fast function, important for -flto. */
7441 fprintf (f, "\\%03o", c);
7442 break;
7443 default:
7444 putc ('\\', f);
7445 putc (escape, f);
7446 break;
7448 s++;
7450 putc ('\"', f);
7451 putc ('\n', f);
7454 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7456 void
7457 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7459 const char *limit = s + len;
7460 const char *last_null = NULL;
7461 unsigned bytes_in_chunk = 0;
7462 unsigned char c;
7463 int escape;
7465 for (; s < limit; s++)
7467 const char *p;
7469 if (bytes_in_chunk >= 60)
7471 putc ('\"', f);
7472 putc ('\n', f);
7473 bytes_in_chunk = 0;
7476 if (s > last_null)
7478 for (p = s; p < limit && *p != '\0'; p++)
7479 continue;
7480 last_null = p;
7482 else
7483 p = last_null;
7485 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7487 if (bytes_in_chunk > 0)
7489 putc ('\"', f);
7490 putc ('\n', f);
7491 bytes_in_chunk = 0;
7494 default_elf_asm_output_limited_string (f, s);
7495 s = p;
7497 else
7499 if (bytes_in_chunk == 0)
7500 fputs (ASCII_DATA_ASM_OP "\"", f);
7502 c = *s;
7503 escape = ELF_ASCII_ESCAPES[c];
7504 switch (escape)
7506 case 0:
7507 putc (c, f);
7508 bytes_in_chunk++;
7509 break;
7510 case 1:
7511 /* TODO: Print in hex with fast function, important for -flto. */
7512 fprintf (f, "\\%03o", c);
7513 bytes_in_chunk += 4;
7514 break;
7515 default:
7516 putc ('\\', f);
7517 putc (escape, f);
7518 bytes_in_chunk += 2;
7519 break;
7525 if (bytes_in_chunk > 0)
7527 putc ('\"', f);
7528 putc ('\n', f);
7531 #endif
7533 static GTY(()) section *elf_init_array_section;
7534 static GTY(()) section *elf_fini_array_section;
7536 static section *
7537 get_elf_initfini_array_priority_section (int priority,
7538 bool constructor_p)
7540 section *sec;
7541 if (priority != DEFAULT_INIT_PRIORITY)
7543 char buf[18];
7544 sprintf (buf, "%s.%.5u",
7545 constructor_p ? ".init_array" : ".fini_array",
7546 priority);
7547 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7549 else
7551 if (constructor_p)
7553 if (elf_init_array_section == NULL)
7554 elf_init_array_section
7555 = get_section (".init_array",
7556 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7557 sec = elf_init_array_section;
7559 else
7561 if (elf_fini_array_section == NULL)
7562 elf_fini_array_section
7563 = get_section (".fini_array",
7564 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7565 sec = elf_fini_array_section;
7568 return sec;
7571 /* Use .init_array section for constructors. */
7573 void
7574 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7576 section *sec = get_elf_initfini_array_priority_section (priority,
7577 true);
7578 assemble_addr_to_section (symbol, sec);
7581 /* Use .fini_array section for destructors. */
7583 void
7584 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7586 section *sec = get_elf_initfini_array_priority_section (priority,
7587 false);
7588 assemble_addr_to_section (symbol, sec);
7591 /* Default TARGET_ASM_OUTPUT_IDENT hook.
7593 This is a bit of a cheat. The real default is a no-op, but this
7594 hook is the default for all targets with a .ident directive. */
7596 void
7597 default_asm_output_ident_directive (const char *ident_str)
7599 const char *ident_asm_op = "\t.ident\t";
7601 /* If we are still in the front end, do not write out the string
7602 to asm_out_file. Instead, add a fake top-level asm statement.
7603 This allows the front ends to use this hook without actually
7604 writing to asm_out_file, to handle #ident or Pragma Ident. */
7605 if (cgraph_state == CGRAPH_STATE_PARSING)
7607 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
7608 add_asm_node (build_string (strlen (buf), buf));
7610 else
7611 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
7614 #include "gt-varasm.h"