Daily bump.
[official-gcc.git] / gcc / varasm.c
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1 /* Output variables, constants and external declarations, for GNU compiler.
2 Copyright (C) 1987-2014 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
21 /* This file handles generation of all the assembler code
22 *except* the instructions of a function.
23 This includes declarations of variables and their initial values.
25 We also output the assembler code for constants stored in memory
26 and are responsible for combining constants with the same value. */
28 #include "config.h"
29 #include "system.h"
30 #include "coretypes.h"
31 #include "tm.h"
32 #include "rtl.h"
33 #include "tree.h"
34 #include "stor-layout.h"
35 #include "stringpool.h"
36 #include "gcc-symtab.h"
37 #include "varasm.h"
38 #include "flags.h"
39 #include "function.h"
40 #include "expr.h"
41 #include "hard-reg-set.h"
42 #include "regs.h"
43 #include "output.h"
44 #include "diagnostic-core.h"
45 #include "hashtab.h"
46 #include "ggc.h"
47 #include "langhooks.h"
48 #include "tm_p.h"
49 #include "debug.h"
50 #include "target.h"
51 #include "common/common-target.h"
52 #include "targhooks.h"
53 #include "cgraph.h"
54 #include "pointer-set.h"
55 #include "asan.h"
56 #include "basic-block.h"
58 #ifdef XCOFF_DEBUGGING_INFO
59 #include "xcoffout.h" /* Needed for external data
60 declarations for e.g. AIX 4.x. */
61 #endif
63 /* The (assembler) name of the first globally-visible object output. */
64 extern GTY(()) const char *first_global_object_name;
65 extern GTY(()) const char *weak_global_object_name;
67 const char *first_global_object_name;
68 const char *weak_global_object_name;
70 struct addr_const;
71 struct constant_descriptor_rtx;
72 struct rtx_constant_pool;
74 #define n_deferred_constants (crtl->varasm.deferred_constants)
76 /* Number for making the label on the next
77 constant that is stored in memory. */
79 static GTY(()) int const_labelno;
81 /* Carry information from ASM_DECLARE_OBJECT_NAME
82 to ASM_FINISH_DECLARE_OBJECT. */
84 int size_directive_output;
86 /* The last decl for which assemble_variable was called,
87 if it did ASM_DECLARE_OBJECT_NAME.
88 If the last call to assemble_variable didn't do that,
89 this holds 0. */
91 tree last_assemble_variable_decl;
93 /* The following global variable indicates if the first basic block
94 in a function belongs to the cold partition or not. */
96 bool first_function_block_is_cold;
98 /* We give all constants their own alias set. Perhaps redundant with
99 MEM_READONLY_P, but pre-dates it. */
101 static alias_set_type const_alias_set;
103 /* Whether we saw any functions with no_split_stack. */
105 static bool saw_no_split_stack;
107 static const char *strip_reg_name (const char *);
108 static int contains_pointers_p (tree);
109 #ifdef ASM_OUTPUT_EXTERNAL
110 static bool incorporeal_function_p (tree);
111 #endif
112 static void decode_addr_const (tree, struct addr_const *);
113 static hashval_t const_desc_hash (const void *);
114 static int const_desc_eq (const void *, const void *);
115 static hashval_t const_hash_1 (const tree);
116 static int compare_constant (const tree, const tree);
117 static tree copy_constant (tree);
118 static void output_constant_def_contents (rtx);
119 static void output_addressed_constants (tree);
120 static unsigned HOST_WIDE_INT output_constant (tree, unsigned HOST_WIDE_INT,
121 unsigned int);
122 static void globalize_decl (tree);
123 static bool decl_readonly_section_1 (enum section_category);
124 #ifdef BSS_SECTION_ASM_OP
125 #ifdef ASM_OUTPUT_ALIGNED_BSS
126 static void asm_output_aligned_bss (FILE *, tree, const char *,
127 unsigned HOST_WIDE_INT, int)
128 ATTRIBUTE_UNUSED;
129 #endif
130 #endif /* BSS_SECTION_ASM_OP */
131 static void mark_weak (tree);
132 static void output_constant_pool (const char *, tree);
134 /* Well-known sections, each one associated with some sort of *_ASM_OP. */
135 section *text_section;
136 section *data_section;
137 section *readonly_data_section;
138 section *sdata_section;
139 section *ctors_section;
140 section *dtors_section;
141 section *bss_section;
142 section *sbss_section;
144 /* Various forms of common section. All are guaranteed to be nonnull. */
145 section *tls_comm_section;
146 section *comm_section;
147 section *lcomm_section;
149 /* A SECTION_NOSWITCH section used for declaring global BSS variables.
150 May be null. */
151 section *bss_noswitch_section;
153 /* The section that holds the main exception table, when known. The section
154 is set either by the target's init_sections hook or by the first call to
155 switch_to_exception_section. */
156 section *exception_section;
158 /* The section that holds the DWARF2 frame unwind information, when known.
159 The section is set either by the target's init_sections hook or by the
160 first call to switch_to_eh_frame_section. */
161 section *eh_frame_section;
163 /* asm_out_file's current section. This is NULL if no section has yet
164 been selected or if we lose track of what the current section is. */
165 section *in_section;
167 /* True if code for the current function is currently being directed
168 at the cold section. */
169 bool in_cold_section_p;
171 /* A linked list of all the unnamed sections. */
172 static GTY(()) section *unnamed_sections;
174 /* Return a nonzero value if DECL has a section attribute. */
175 #define IN_NAMED_SECTION(DECL) \
176 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \
177 && DECL_SECTION_NAME (DECL) != NULL_TREE)
179 /* Hash table of named sections. */
180 static GTY((param_is (section))) htab_t section_htab;
182 /* A table of object_blocks, indexed by section. */
183 static GTY((param_is (struct object_block))) htab_t object_block_htab;
185 /* The next number to use for internal anchor labels. */
186 static GTY(()) int anchor_labelno;
188 /* A pool of constants that can be shared between functions. */
189 static GTY(()) struct rtx_constant_pool *shared_constant_pool;
191 /* Helper routines for maintaining section_htab. */
193 static int
194 section_entry_eq (const void *p1, const void *p2)
196 const section *old = (const section *) p1;
197 const char *new_name = (const char *) p2;
199 return strcmp (old->named.name, new_name) == 0;
202 static hashval_t
203 section_entry_hash (const void *p)
205 const section *old = (const section *) p;
206 return htab_hash_string (old->named.name);
209 /* Return a hash value for section SECT. */
211 static hashval_t
212 hash_section (section *sect)
214 if (sect->common.flags & SECTION_NAMED)
215 return htab_hash_string (sect->named.name);
216 return sect->common.flags;
219 /* Helper routines for maintaining object_block_htab. */
221 static int
222 object_block_entry_eq (const void *p1, const void *p2)
224 const struct object_block *old = (const struct object_block *) p1;
225 const section *new_section = (const section *) p2;
227 return old->sect == new_section;
230 static hashval_t
231 object_block_entry_hash (const void *p)
233 const struct object_block *old = (const struct object_block *) p;
234 return hash_section (old->sect);
237 /* Return a new unnamed section with the given fields. */
239 section *
240 get_unnamed_section (unsigned int flags, void (*callback) (const void *),
241 const void *data)
243 section *sect;
245 sect = ggc_alloc_section ();
246 sect->unnamed.common.flags = flags | SECTION_UNNAMED;
247 sect->unnamed.callback = callback;
248 sect->unnamed.data = data;
249 sect->unnamed.next = unnamed_sections;
251 unnamed_sections = sect;
252 return sect;
255 /* Return a SECTION_NOSWITCH section with the given fields. */
257 static section *
258 get_noswitch_section (unsigned int flags, noswitch_section_callback callback)
260 section *sect;
262 sect = ggc_alloc_section ();
263 sect->noswitch.common.flags = flags | SECTION_NOSWITCH;
264 sect->noswitch.callback = callback;
266 return sect;
269 /* Return the named section structure associated with NAME. Create
270 a new section with the given fields if no such structure exists. */
272 section *
273 get_section (const char *name, unsigned int flags, tree decl)
275 section *sect, **slot;
277 slot = (section **)
278 htab_find_slot_with_hash (section_htab, name,
279 htab_hash_string (name), INSERT);
280 flags |= SECTION_NAMED;
281 if (*slot == NULL)
283 sect = ggc_alloc_section ();
284 sect->named.common.flags = flags;
285 sect->named.name = ggc_strdup (name);
286 sect->named.decl = decl;
287 *slot = sect;
289 else
291 sect = *slot;
292 if ((sect->common.flags & ~SECTION_DECLARED) != flags
293 && ((sect->common.flags | flags) & SECTION_OVERRIDE) == 0)
295 /* It is fine if one of the section flags is
296 SECTION_WRITE | SECTION_RELRO and the other has none of these
297 flags (i.e. read-only) in named sections and either the
298 section hasn't been declared yet or has been declared as writable.
299 In that case just make sure the resulting flags are
300 SECTION_WRITE | SECTION_RELRO, ie. writable only because of
301 relocations. */
302 if (((sect->common.flags ^ flags) & (SECTION_WRITE | SECTION_RELRO))
303 == (SECTION_WRITE | SECTION_RELRO)
304 && (sect->common.flags
305 & ~(SECTION_DECLARED | SECTION_WRITE | SECTION_RELRO))
306 == (flags & ~(SECTION_WRITE | SECTION_RELRO))
307 && ((sect->common.flags & SECTION_DECLARED) == 0
308 || (sect->common.flags & SECTION_WRITE)))
310 sect->common.flags |= (SECTION_WRITE | SECTION_RELRO);
311 return sect;
313 /* Sanity check user variables for flag changes. */
314 if (sect->named.decl != NULL
315 && DECL_P (sect->named.decl)
316 && decl != sect->named.decl)
318 if (decl != NULL && DECL_P (decl))
319 error ("%+D causes a section type conflict with %D",
320 decl, sect->named.decl);
321 else
322 error ("section type conflict with %D", sect->named.decl);
323 inform (DECL_SOURCE_LOCATION (sect->named.decl),
324 "%qD was declared here", sect->named.decl);
326 else if (decl != NULL && DECL_P (decl))
327 error ("%+D causes a section type conflict", decl);
328 else
329 error ("section type conflict");
330 /* Make sure we don't error about one section multiple times. */
331 sect->common.flags |= SECTION_OVERRIDE;
334 return sect;
337 /* Return true if the current compilation mode benefits from having
338 objects grouped into blocks. */
340 static bool
341 use_object_blocks_p (void)
343 return flag_section_anchors;
346 /* Return the object_block structure for section SECT. Create a new
347 structure if we haven't created one already. Return null if SECT
348 itself is null. */
350 static struct object_block *
351 get_block_for_section (section *sect)
353 struct object_block *block;
354 void **slot;
356 if (sect == NULL)
357 return NULL;
359 slot = htab_find_slot_with_hash (object_block_htab, sect,
360 hash_section (sect), INSERT);
361 block = (struct object_block *) *slot;
362 if (block == NULL)
364 block = ggc_alloc_cleared_object_block ();
365 block->sect = sect;
366 *slot = block;
368 return block;
371 /* Create a symbol with label LABEL and place it at byte offset
372 OFFSET in BLOCK. OFFSET can be negative if the symbol's offset
373 is not yet known. LABEL must be a garbage-collected string. */
375 static rtx
376 create_block_symbol (const char *label, struct object_block *block,
377 HOST_WIDE_INT offset)
379 rtx symbol;
380 unsigned int size;
382 /* Create the extended SYMBOL_REF. */
383 size = RTX_HDR_SIZE + sizeof (struct block_symbol);
384 symbol = ggc_alloc_rtx_def (size);
386 /* Initialize the normal SYMBOL_REF fields. */
387 memset (symbol, 0, size);
388 PUT_CODE (symbol, SYMBOL_REF);
389 PUT_MODE (symbol, Pmode);
390 XSTR (symbol, 0) = label;
391 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_HAS_BLOCK_INFO;
393 /* Initialize the block_symbol stuff. */
394 SYMBOL_REF_BLOCK (symbol) = block;
395 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
397 return symbol;
400 /* Return a section with a particular name and with whatever SECTION_*
401 flags section_type_flags deems appropriate. The name of the section
402 is taken from NAME if nonnull, otherwise it is taken from DECL's
403 DECL_SECTION_NAME. DECL is the decl associated with the section
404 (see the section comment for details) and RELOC is as for
405 section_type_flags. */
407 section *
408 get_named_section (tree decl, const char *name, int reloc)
410 unsigned int flags;
412 if (name == NULL)
414 gcc_assert (decl && DECL_P (decl) && DECL_SECTION_NAME (decl));
415 name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
418 flags = targetm.section_type_flags (decl, name, reloc);
419 return get_section (name, flags, decl);
422 /* If required, set DECL_SECTION_NAME to a unique name. */
424 void
425 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
426 int flag_function_or_data_sections)
428 if (DECL_SECTION_NAME (decl) == NULL_TREE
429 && targetm_common.have_named_sections
430 && (flag_function_or_data_sections
431 || DECL_ONE_ONLY (decl)))
433 targetm.asm_out.unique_section (decl, reloc);
434 DECL_HAS_IMPLICIT_SECTION_NAME_P (decl) = true;
438 #ifdef BSS_SECTION_ASM_OP
440 #ifdef ASM_OUTPUT_ALIGNED_BSS
442 /* Utility function for targets to use in implementing
443 ASM_OUTPUT_ALIGNED_BSS.
444 ??? It is believed that this function will work in most cases so such
445 support is localized here. */
447 static void
448 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
449 const char *name, unsigned HOST_WIDE_INT size,
450 int align)
452 switch_to_section (bss_section);
453 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
454 #ifdef ASM_DECLARE_OBJECT_NAME
455 last_assemble_variable_decl = decl;
456 ASM_DECLARE_OBJECT_NAME (file, name, decl);
457 #else
458 /* Standard thing is just output label for the object. */
459 ASM_OUTPUT_LABEL (file, name);
460 #endif /* ASM_DECLARE_OBJECT_NAME */
461 ASM_OUTPUT_SKIP (file, size ? size : 1);
464 #endif
466 #endif /* BSS_SECTION_ASM_OP */
468 #ifndef USE_SELECT_SECTION_FOR_FUNCTIONS
469 /* Return the hot section for function DECL. Return text_section for
470 null DECLs. */
472 static section *
473 hot_function_section (tree decl)
475 if (decl != NULL_TREE
476 && DECL_SECTION_NAME (decl) != NULL_TREE
477 && targetm_common.have_named_sections)
478 return get_named_section (decl, NULL, 0);
479 else
480 return text_section;
482 #endif
484 /* Return section for TEXT_SECTION_NAME if DECL or DECL_SECTION_NAME (DECL)
485 is NULL.
487 When DECL_SECTION_NAME is non-NULL and it is implicit section and
488 NAMED_SECTION_SUFFIX is non-NULL, then produce section called
489 concatenate the name with NAMED_SECTION_SUFFIX.
490 Otherwise produce "TEXT_SECTION_NAME.IMPLICIT_NAME". */
492 section *
493 get_named_text_section (tree decl,
494 const char *text_section_name,
495 const char *named_section_suffix)
497 if (decl && DECL_SECTION_NAME (decl))
499 if (named_section_suffix)
501 tree dsn = DECL_SECTION_NAME (decl);
502 const char *stripped_name;
503 char *name, *buffer;
505 name = (char *) alloca (TREE_STRING_LENGTH (dsn) + 1);
506 memcpy (name, TREE_STRING_POINTER (dsn),
507 TREE_STRING_LENGTH (dsn) + 1);
509 stripped_name = targetm.strip_name_encoding (name);
511 buffer = ACONCAT ((stripped_name, named_section_suffix, NULL));
512 return get_named_section (decl, buffer, 0);
514 else if (DECL_HAS_IMPLICIT_SECTION_NAME_P (decl))
516 const char *name;
518 /* Do not try to split gnu_linkonce functions. This gets somewhat
519 slipperly. */
520 if (DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP)
521 return NULL;
522 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
523 name = targetm.strip_name_encoding (name);
524 return get_named_section (decl, ACONCAT ((text_section_name, ".",
525 name, NULL)), 0);
527 else
528 return NULL;
530 return get_named_section (decl, text_section_name, 0);
533 /* Choose named function section based on its frequency. */
535 section *
536 default_function_section (tree decl, enum node_frequency freq,
537 bool startup, bool exit)
539 #if defined HAVE_LD_EH_GC_SECTIONS && defined HAVE_LD_EH_GC_SECTIONS_BUG
540 /* Old GNU linkers have buggy --gc-section support, which sometimes
541 results in .gcc_except_table* sections being garbage collected. */
542 if (decl
543 && DECL_SECTION_NAME (decl)
544 && DECL_HAS_IMPLICIT_SECTION_NAME_P (decl))
545 return NULL;
546 #endif
548 if (!flag_reorder_functions
549 || !targetm_common.have_named_sections)
550 return NULL;
551 /* Startup code should go to startup subsection unless it is
552 unlikely executed (this happens especially with function splitting
553 where we can split away unnecessary parts of static constructors. */
554 if (startup && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
556 /* If we do have a profile or(and) LTO phase is executed, we do not need
557 these ELF section. */
558 if (!in_lto_p || !flag_profile_values)
559 return get_named_text_section (decl, ".text.startup", NULL);
560 else
561 return NULL;
564 /* Similarly for exit. */
565 if (exit && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
566 return get_named_text_section (decl, ".text.exit", NULL);
568 /* Group cold functions together, similarly for hot code. */
569 switch (freq)
571 case NODE_FREQUENCY_UNLIKELY_EXECUTED:
572 return get_named_text_section (decl, ".text.unlikely", NULL);
573 case NODE_FREQUENCY_HOT:
574 /* If we do have a profile or(and) LTO phase is executed, we do not need
575 these ELF section. */
576 if (!in_lto_p || !flag_profile_values)
577 return get_named_text_section (decl, ".text.hot", NULL);
578 default:
579 return NULL;
583 /* Return the section for function DECL.
585 If DECL is NULL_TREE, return the text section. We can be passed
586 NULL_TREE under some circumstances by dbxout.c at least.
588 If FORCE_COLD is true, return cold function section ignoring
589 the frequency info of cgraph_node. */
591 static section *
592 function_section_1 (tree decl, bool force_cold)
594 section *section = NULL;
595 enum node_frequency freq = NODE_FREQUENCY_NORMAL;
596 bool startup = false, exit = false;
598 if (decl)
600 struct cgraph_node *node = cgraph_get_node (decl);
602 if (node)
604 freq = node->frequency;
605 startup = node->only_called_at_startup;
606 exit = node->only_called_at_exit;
609 if (force_cold)
610 freq = NODE_FREQUENCY_UNLIKELY_EXECUTED;
612 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
613 if (decl != NULL_TREE
614 && DECL_SECTION_NAME (decl) != NULL_TREE)
616 if (targetm.asm_out.function_section)
617 section = targetm.asm_out.function_section (decl, freq,
618 startup, exit);
619 if (section)
620 return section;
621 return get_named_section (decl, NULL, 0);
623 else
624 return targetm.asm_out.select_section
625 (decl, freq == NODE_FREQUENCY_UNLIKELY_EXECUTED,
626 DECL_ALIGN (decl));
627 #else
628 if (targetm.asm_out.function_section)
629 section = targetm.asm_out.function_section (decl, freq, startup, exit);
630 if (section)
631 return section;
632 return hot_function_section (decl);
633 #endif
636 /* Return the section for function DECL.
638 If DECL is NULL_TREE, return the text section. We can be passed
639 NULL_TREE under some circumstances by dbxout.c at least. */
641 section *
642 function_section (tree decl)
644 /* Handle cases where function splitting code decides
645 to put function entry point into unlikely executed section
646 despite the fact that the function itself is not cold
647 (i.e. it is called rarely but contains a hot loop that is
648 better to live in hot subsection for the code locality). */
649 return function_section_1 (decl,
650 first_function_block_is_cold);
653 /* Return the section for the current function, take IN_COLD_SECTION_P
654 into account. */
656 section *
657 current_function_section (void)
659 return function_section_1 (current_function_decl, in_cold_section_p);
662 /* Tell assembler to switch to unlikely-to-be-executed text section. */
664 section *
665 unlikely_text_section (void)
667 return function_section_1 (current_function_decl, true);
670 /* When called within a function context, return true if the function
671 has been assigned a cold text section and if SECT is that section.
672 When called outside a function context, return true if SECT is the
673 default cold section. */
675 bool
676 unlikely_text_section_p (section *sect)
678 return sect == function_section_1 (current_function_decl, true);
681 /* Return the read-only data section associated with function DECL. */
683 section *
684 default_function_rodata_section (tree decl)
686 if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
688 const char *name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
690 if (DECL_ONE_ONLY (decl) && HAVE_COMDAT_GROUP)
692 const char *dot;
693 size_t len;
694 char* rname;
696 dot = strchr (name + 1, '.');
697 if (!dot)
698 dot = name;
699 len = strlen (dot) + 8;
700 rname = (char *) alloca (len);
702 strcpy (rname, ".rodata");
703 strcat (rname, dot);
704 return get_section (rname, SECTION_LINKONCE, decl);
706 /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo. */
707 else if (DECL_ONE_ONLY (decl)
708 && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
710 size_t len = strlen (name) + 1;
711 char *rname = (char *) alloca (len);
713 memcpy (rname, name, len);
714 rname[14] = 'r';
715 return get_section (rname, SECTION_LINKONCE, decl);
717 /* For .text.foo we want to use .rodata.foo. */
718 else if (flag_function_sections && flag_data_sections
719 && strncmp (name, ".text.", 6) == 0)
721 size_t len = strlen (name) + 1;
722 char *rname = (char *) alloca (len + 2);
724 memcpy (rname, ".rodata", 7);
725 memcpy (rname + 7, name + 5, len - 5);
726 return get_section (rname, 0, decl);
730 return readonly_data_section;
733 /* Return the read-only data section associated with function DECL
734 for targets where that section should be always the single
735 readonly data section. */
737 section *
738 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
740 return readonly_data_section;
743 /* Return the section to use for string merging. */
745 static section *
746 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
747 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
748 unsigned int flags ATTRIBUTE_UNUSED)
750 HOST_WIDE_INT len;
752 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
753 && TREE_CODE (decl) == STRING_CST
754 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
755 && align <= 256
756 && (len = int_size_in_bytes (TREE_TYPE (decl))) > 0
757 && TREE_STRING_LENGTH (decl) >= len)
759 enum machine_mode mode;
760 unsigned int modesize;
761 const char *str;
762 HOST_WIDE_INT i;
763 int j, unit;
764 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
765 char *name = (char *) alloca (strlen (prefix) + 30);
767 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
768 modesize = GET_MODE_BITSIZE (mode);
769 if (modesize >= 8 && modesize <= 256
770 && (modesize & (modesize - 1)) == 0)
772 if (align < modesize)
773 align = modesize;
775 str = TREE_STRING_POINTER (decl);
776 unit = GET_MODE_SIZE (mode);
778 /* Check for embedded NUL characters. */
779 for (i = 0; i < len; i += unit)
781 for (j = 0; j < unit; j++)
782 if (str[i + j] != '\0')
783 break;
784 if (j == unit)
785 break;
787 if (i == len - unit)
789 sprintf (name, "%s.str%d.%d", prefix,
790 modesize / 8, (int) (align / 8));
791 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
792 return get_section (name, flags, NULL);
797 return readonly_data_section;
800 /* Return the section to use for constant merging. */
802 section *
803 mergeable_constant_section (enum machine_mode mode ATTRIBUTE_UNUSED,
804 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
805 unsigned int flags ATTRIBUTE_UNUSED)
807 unsigned int modesize = GET_MODE_BITSIZE (mode);
809 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
810 && mode != VOIDmode
811 && mode != BLKmode
812 && modesize <= align
813 && align >= 8
814 && align <= 256
815 && (align & (align - 1)) == 0)
817 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
818 char *name = (char *) alloca (strlen (prefix) + 30);
820 sprintf (name, "%s.cst%d", prefix, (int) (align / 8));
821 flags |= (align / 8) | SECTION_MERGE;
822 return get_section (name, flags, NULL);
824 return readonly_data_section;
827 /* Given NAME, a putative register name, discard any customary prefixes. */
829 static const char *
830 strip_reg_name (const char *name)
832 #ifdef REGISTER_PREFIX
833 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
834 name += strlen (REGISTER_PREFIX);
835 #endif
836 if (name[0] == '%' || name[0] == '#')
837 name++;
838 return name;
841 /* The user has asked for a DECL to have a particular name. Set (or
842 change) it in such a way that we don't prefix an underscore to
843 it. */
844 void
845 set_user_assembler_name (tree decl, const char *name)
847 char *starred = (char *) alloca (strlen (name) + 2);
848 starred[0] = '*';
849 strcpy (starred + 1, name);
850 change_decl_assembler_name (decl, get_identifier (starred));
851 SET_DECL_RTL (decl, NULL_RTX);
854 /* Decode an `asm' spec for a declaration as a register name.
855 Return the register number, or -1 if nothing specified,
856 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
857 or -3 if ASMSPEC is `cc' and is not recognized,
858 or -4 if ASMSPEC is `memory' and is not recognized.
859 Accept an exact spelling or a decimal number.
860 Prefixes such as % are optional. */
863 decode_reg_name_and_count (const char *asmspec, int *pnregs)
865 /* Presume just one register is clobbered. */
866 *pnregs = 1;
868 if (asmspec != 0)
870 int i;
872 /* Get rid of confusing prefixes. */
873 asmspec = strip_reg_name (asmspec);
875 /* Allow a decimal number as a "register name". */
876 for (i = strlen (asmspec) - 1; i >= 0; i--)
877 if (! ISDIGIT (asmspec[i]))
878 break;
879 if (asmspec[0] != 0 && i < 0)
881 i = atoi (asmspec);
882 if (i < FIRST_PSEUDO_REGISTER && i >= 0)
883 return i;
884 else
885 return -2;
888 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
889 if (reg_names[i][0]
890 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
891 return i;
893 #ifdef OVERLAPPING_REGISTER_NAMES
895 static const struct
897 const char *const name;
898 const int number;
899 const int nregs;
900 } table[] = OVERLAPPING_REGISTER_NAMES;
902 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
903 if (table[i].name[0]
904 && ! strcmp (asmspec, table[i].name))
906 *pnregs = table[i].nregs;
907 return table[i].number;
910 #endif /* OVERLAPPING_REGISTER_NAMES */
912 #ifdef ADDITIONAL_REGISTER_NAMES
914 static const struct { const char *const name; const int number; } table[]
915 = ADDITIONAL_REGISTER_NAMES;
917 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
918 if (table[i].name[0]
919 && ! strcmp (asmspec, table[i].name))
920 return table[i].number;
922 #endif /* ADDITIONAL_REGISTER_NAMES */
924 if (!strcmp (asmspec, "memory"))
925 return -4;
927 if (!strcmp (asmspec, "cc"))
928 return -3;
930 return -2;
933 return -1;
937 decode_reg_name (const char *name)
939 int count;
940 return decode_reg_name_and_count (name, &count);
944 /* Return true if DECL's initializer is suitable for a BSS section. */
946 bool
947 bss_initializer_p (const_tree decl)
949 return (DECL_INITIAL (decl) == NULL
950 || DECL_INITIAL (decl) == error_mark_node
951 || (flag_zero_initialized_in_bss
952 /* Leave constant zeroes in .rodata so they
953 can be shared. */
954 && !TREE_READONLY (decl)
955 && initializer_zerop (DECL_INITIAL (decl))));
958 /* Compute the alignment of variable specified by DECL.
959 DONT_OUTPUT_DATA is from assemble_variable. */
961 void
962 align_variable (tree decl, bool dont_output_data)
964 unsigned int align = DECL_ALIGN (decl);
966 /* In the case for initialing an array whose length isn't specified,
967 where we have not yet been able to do the layout,
968 figure out the proper alignment now. */
969 if (dont_output_data && DECL_SIZE (decl) == 0
970 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
971 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
973 /* Some object file formats have a maximum alignment which they support.
974 In particular, a.out format supports a maximum alignment of 4. */
975 if (align > MAX_OFILE_ALIGNMENT)
977 error ("alignment of %q+D is greater than maximum object "
978 "file alignment %d", decl,
979 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
980 align = MAX_OFILE_ALIGNMENT;
983 if (! DECL_USER_ALIGN (decl))
985 #ifdef DATA_ABI_ALIGNMENT
986 unsigned int data_abi_align
987 = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
988 /* For backwards compatibility, don't assume the ABI alignment for
989 TLS variables. */
990 if (! DECL_THREAD_LOCAL_P (decl) || data_abi_align <= BITS_PER_WORD)
991 align = data_abi_align;
992 #endif
994 /* On some machines, it is good to increase alignment sometimes.
995 But as DECL_ALIGN is used both for actually emitting the variable
996 and for code accessing the variable as guaranteed alignment, we
997 can only increase the alignment if it is a performance optimization
998 if the references to it must bind to the current definition. */
999 if (decl_binds_to_current_def_p (decl))
1001 #ifdef DATA_ALIGNMENT
1002 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1003 /* Don't increase alignment too much for TLS variables - TLS space
1004 is too precious. */
1005 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1006 align = data_align;
1007 #endif
1008 #ifdef CONSTANT_ALIGNMENT
1009 if (DECL_INITIAL (decl) != 0
1010 && DECL_INITIAL (decl) != error_mark_node)
1012 unsigned int const_align
1013 = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
1014 /* Don't increase alignment too much for TLS variables - TLS
1015 space is too precious. */
1016 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1017 align = const_align;
1019 #endif
1023 /* Reset the alignment in case we have made it tighter, so we can benefit
1024 from it in get_pointer_alignment. */
1025 DECL_ALIGN (decl) = align;
1028 /* Return DECL_ALIGN (decl), possibly increased for optimization purposes
1029 beyond what align_variable returned. */
1031 static unsigned int
1032 get_variable_align (tree decl)
1034 unsigned int align = DECL_ALIGN (decl);
1036 /* For user aligned vars or static vars align_variable already did
1037 everything. */
1038 if (DECL_USER_ALIGN (decl) || !TREE_PUBLIC (decl))
1039 return align;
1041 #ifdef DATA_ABI_ALIGNMENT
1042 if (DECL_THREAD_LOCAL_P (decl))
1043 align = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1044 #endif
1046 /* For decls that bind to the current definition, align_variable
1047 did also everything, except for not assuming ABI required alignment
1048 of TLS variables. For other vars, increase the alignment here
1049 as an optimization. */
1050 if (!decl_binds_to_current_def_p (decl))
1052 /* On some machines, it is good to increase alignment sometimes. */
1053 #ifdef DATA_ALIGNMENT
1054 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1055 /* Don't increase alignment too much for TLS variables - TLS space
1056 is too precious. */
1057 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1058 align = data_align;
1059 #endif
1060 #ifdef CONSTANT_ALIGNMENT
1061 if (DECL_INITIAL (decl) != 0 && DECL_INITIAL (decl) != error_mark_node)
1063 unsigned int const_align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl),
1064 align);
1065 /* Don't increase alignment too much for TLS variables - TLS space
1066 is too precious. */
1067 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1068 align = const_align;
1070 #endif
1073 return align;
1076 /* Return the section into which the given VAR_DECL or CONST_DECL
1077 should be placed. PREFER_NOSWITCH_P is true if a noswitch
1078 section should be used wherever possible. */
1080 section *
1081 get_variable_section (tree decl, bool prefer_noswitch_p)
1083 addr_space_t as = ADDR_SPACE_GENERIC;
1084 int reloc;
1086 if (TREE_TYPE (decl) != error_mark_node)
1087 as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1089 if (DECL_COMMON (decl))
1091 /* If the decl has been given an explicit section name, or it resides
1092 in a non-generic address space, then it isn't common, and shouldn't
1093 be handled as such. */
1094 gcc_assert (DECL_SECTION_NAME (decl) == NULL
1095 && ADDR_SPACE_GENERIC_P (as));
1096 if (DECL_THREAD_LOCAL_P (decl))
1097 return tls_comm_section;
1098 else if (TREE_PUBLIC (decl) && bss_initializer_p (decl))
1099 return comm_section;
1102 if (DECL_INITIAL (decl) == error_mark_node)
1103 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1104 else if (DECL_INITIAL (decl))
1105 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1106 else
1107 reloc = 0;
1109 resolve_unique_section (decl, reloc, flag_data_sections);
1110 if (IN_NAMED_SECTION (decl))
1111 return get_named_section (decl, NULL, reloc);
1113 if (ADDR_SPACE_GENERIC_P (as)
1114 && !DECL_THREAD_LOCAL_P (decl)
1115 && !(prefer_noswitch_p && targetm.have_switchable_bss_sections)
1116 && bss_initializer_p (decl))
1118 if (!TREE_PUBLIC (decl)
1119 && !((flag_sanitize & SANITIZE_ADDRESS)
1120 && asan_protect_global (decl)))
1121 return lcomm_section;
1122 if (bss_noswitch_section)
1123 return bss_noswitch_section;
1126 return targetm.asm_out.select_section (decl, reloc,
1127 get_variable_align (decl));
1130 /* Return the block into which object_block DECL should be placed. */
1132 static struct object_block *
1133 get_block_for_decl (tree decl)
1135 section *sect;
1137 if (TREE_CODE (decl) == VAR_DECL)
1139 /* The object must be defined in this translation unit. */
1140 if (DECL_EXTERNAL (decl))
1141 return NULL;
1143 /* There's no point using object blocks for something that is
1144 isolated by definition. */
1145 if (DECL_ONE_ONLY (decl))
1146 return NULL;
1149 /* We can only calculate block offsets if the decl has a known
1150 constant size. */
1151 if (DECL_SIZE_UNIT (decl) == NULL)
1152 return NULL;
1153 if (!tree_fits_uhwi_p (DECL_SIZE_UNIT (decl)))
1154 return NULL;
1156 /* Find out which section should contain DECL. We cannot put it into
1157 an object block if it requires a standalone definition. */
1158 if (TREE_CODE (decl) == VAR_DECL)
1159 align_variable (decl, 0);
1160 sect = get_variable_section (decl, true);
1161 if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
1162 return NULL;
1164 return get_block_for_section (sect);
1167 /* Make sure block symbol SYMBOL is in block BLOCK. */
1169 static void
1170 change_symbol_block (rtx symbol, struct object_block *block)
1172 if (block != SYMBOL_REF_BLOCK (symbol))
1174 gcc_assert (SYMBOL_REF_BLOCK_OFFSET (symbol) < 0);
1175 SYMBOL_REF_BLOCK (symbol) = block;
1179 /* Return true if it is possible to put DECL in an object_block. */
1181 static bool
1182 use_blocks_for_decl_p (tree decl)
1184 /* Only data DECLs can be placed into object blocks. */
1185 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != CONST_DECL)
1186 return false;
1188 /* Detect decls created by dw2_force_const_mem. Such decls are
1189 special because DECL_INITIAL doesn't specify the decl's true value.
1190 dw2_output_indirect_constants will instead call assemble_variable
1191 with dont_output_data set to 1 and then print the contents itself. */
1192 if (DECL_INITIAL (decl) == decl)
1193 return false;
1195 /* If this decl is an alias, then we don't want to emit a
1196 definition. */
1197 if (lookup_attribute ("alias", DECL_ATTRIBUTES (decl)))
1198 return false;
1200 return targetm.use_blocks_for_decl_p (decl);
1203 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
1204 have static storage duration. In other words, it should not be an
1205 automatic variable, including PARM_DECLs.
1207 There is, however, one exception: this function handles variables
1208 explicitly placed in a particular register by the user.
1210 This is never called for PARM_DECL nodes. */
1212 void
1213 make_decl_rtl (tree decl)
1215 const char *name = 0;
1216 int reg_number;
1217 rtx x;
1219 /* Check that we are not being given an automatic variable. */
1220 gcc_assert (TREE_CODE (decl) != PARM_DECL
1221 && TREE_CODE (decl) != RESULT_DECL);
1223 /* A weak alias has TREE_PUBLIC set but not the other bits. */
1224 gcc_assert (TREE_CODE (decl) != VAR_DECL
1225 || TREE_STATIC (decl)
1226 || TREE_PUBLIC (decl)
1227 || DECL_EXTERNAL (decl)
1228 || DECL_REGISTER (decl));
1230 /* And that we were not given a type or a label. */
1231 gcc_assert (TREE_CODE (decl) != TYPE_DECL
1232 && TREE_CODE (decl) != LABEL_DECL);
1234 /* For a duplicate declaration, we can be called twice on the
1235 same DECL node. Don't discard the RTL already made. */
1236 if (DECL_RTL_SET_P (decl))
1238 /* If the old RTL had the wrong mode, fix the mode. */
1239 x = DECL_RTL (decl);
1240 if (GET_MODE (x) != DECL_MODE (decl))
1241 SET_DECL_RTL (decl, adjust_address_nv (x, DECL_MODE (decl), 0));
1243 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1244 return;
1246 /* ??? Another way to do this would be to maintain a hashed
1247 table of such critters. Instead of adding stuff to a DECL
1248 to give certain attributes to it, we could use an external
1249 hash map from DECL to set of attributes. */
1251 /* Let the target reassign the RTL if it wants.
1252 This is necessary, for example, when one machine specific
1253 decl attribute overrides another. */
1254 targetm.encode_section_info (decl, DECL_RTL (decl), false);
1256 /* If the symbol has a SYMBOL_REF_BLOCK field, update it based
1257 on the new decl information. */
1258 if (MEM_P (x)
1259 && GET_CODE (XEXP (x, 0)) == SYMBOL_REF
1260 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (x, 0)))
1261 change_symbol_block (XEXP (x, 0), get_block_for_decl (decl));
1263 return;
1266 /* If this variable belongs to the global constant pool, retrieve the
1267 pre-computed RTL or recompute it in LTO mode. */
1268 if (TREE_CODE (decl) == VAR_DECL && DECL_IN_CONSTANT_POOL (decl))
1270 SET_DECL_RTL (decl, output_constant_def (DECL_INITIAL (decl), 1));
1271 return;
1274 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
1276 if (name[0] != '*' && TREE_CODE (decl) != FUNCTION_DECL
1277 && DECL_REGISTER (decl))
1279 error ("register name not specified for %q+D", decl);
1281 else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1283 const char *asmspec = name+1;
1284 enum machine_mode mode = DECL_MODE (decl);
1285 reg_number = decode_reg_name (asmspec);
1286 /* First detect errors in declaring global registers. */
1287 if (reg_number == -1)
1288 error ("register name not specified for %q+D", decl);
1289 else if (reg_number < 0)
1290 error ("invalid register name for %q+D", decl);
1291 else if (mode == BLKmode)
1292 error ("data type of %q+D isn%'t suitable for a register",
1293 decl);
1294 else if (!in_hard_reg_set_p (accessible_reg_set, mode, reg_number))
1295 error ("the register specified for %q+D cannot be accessed"
1296 " by the current target", decl);
1297 else if (!in_hard_reg_set_p (operand_reg_set, mode, reg_number))
1298 error ("the register specified for %q+D is not general enough"
1299 " to be used as a register variable", decl);
1300 else if (!HARD_REGNO_MODE_OK (reg_number, mode))
1301 error ("register specified for %q+D isn%'t suitable for data type",
1302 decl);
1303 /* Now handle properly declared static register variables. */
1304 else
1306 int nregs;
1308 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
1310 DECL_INITIAL (decl) = 0;
1311 error ("global register variable has initial value");
1313 if (TREE_THIS_VOLATILE (decl))
1314 warning (OPT_Wvolatile_register_var,
1315 "optimization may eliminate reads and/or "
1316 "writes to register variables");
1318 /* If the user specified one of the eliminables registers here,
1319 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
1320 confused with that register and be eliminated. This usage is
1321 somewhat suspect... */
1323 SET_DECL_RTL (decl, gen_rtx_raw_REG (mode, reg_number));
1324 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
1325 REG_USERVAR_P (DECL_RTL (decl)) = 1;
1327 if (TREE_STATIC (decl))
1329 /* Make this register global, so not usable for anything
1330 else. */
1331 #ifdef ASM_DECLARE_REGISTER_GLOBAL
1332 name = IDENTIFIER_POINTER (DECL_NAME (decl));
1333 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
1334 #endif
1335 nregs = hard_regno_nregs[reg_number][mode];
1336 while (nregs > 0)
1337 globalize_reg (decl, reg_number + --nregs);
1340 /* As a register variable, it has no section. */
1341 return;
1344 /* Now handle ordinary static variables and functions (in memory).
1345 Also handle vars declared register invalidly. */
1346 else if (name[0] == '*')
1348 #ifdef REGISTER_PREFIX
1349 if (strlen (REGISTER_PREFIX) != 0)
1351 reg_number = decode_reg_name (name);
1352 if (reg_number >= 0 || reg_number == -3)
1353 error ("register name given for non-register variable %q+D", decl);
1355 #endif
1358 /* Specifying a section attribute on a variable forces it into a
1359 non-.bss section, and thus it cannot be common. */
1360 /* FIXME: In general this code should not be necessary because
1361 visibility pass is doing the same work. But notice_global_symbol
1362 is called early and it needs to make DECL_RTL to get the name.
1363 we take care of recomputing the DECL_RTL after visibility is changed. */
1364 if (TREE_CODE (decl) == VAR_DECL
1365 && DECL_SECTION_NAME (decl) != NULL_TREE
1366 && DECL_INITIAL (decl) == NULL_TREE
1367 && DECL_COMMON (decl))
1368 DECL_COMMON (decl) = 0;
1370 /* Variables can't be both common and weak. */
1371 if (TREE_CODE (decl) == VAR_DECL && DECL_WEAK (decl))
1372 DECL_COMMON (decl) = 0;
1374 if (use_object_blocks_p () && use_blocks_for_decl_p (decl))
1375 x = create_block_symbol (name, get_block_for_decl (decl), -1);
1376 else
1378 enum machine_mode address_mode = Pmode;
1379 if (TREE_TYPE (decl) != error_mark_node)
1381 addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1382 address_mode = targetm.addr_space.address_mode (as);
1384 x = gen_rtx_SYMBOL_REF (address_mode, name);
1386 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
1387 SET_SYMBOL_REF_DECL (x, decl);
1389 x = gen_rtx_MEM (DECL_MODE (decl), x);
1390 if (TREE_CODE (decl) != FUNCTION_DECL)
1391 set_mem_attributes (x, decl, 1);
1392 SET_DECL_RTL (decl, x);
1394 /* Optionally set flags or add text to the name to record information
1395 such as that it is a function name.
1396 If the name is changed, the macro ASM_OUTPUT_LABELREF
1397 will have to know how to strip this information. */
1398 targetm.encode_section_info (decl, DECL_RTL (decl), true);
1401 /* Like make_decl_rtl, but inhibit creation of new alias sets when
1402 calling make_decl_rtl. Also, reset DECL_RTL before returning the
1403 rtl. */
1406 make_decl_rtl_for_debug (tree decl)
1408 unsigned int save_aliasing_flag;
1409 rtx rtl;
1411 if (DECL_RTL_SET_P (decl))
1412 return DECL_RTL (decl);
1414 /* Kludge alert! Somewhere down the call chain, make_decl_rtl will
1415 call new_alias_set. If running with -fcompare-debug, sometimes
1416 we do not want to create alias sets that will throw the alias
1417 numbers off in the comparison dumps. So... clearing
1418 flag_strict_aliasing will keep new_alias_set() from creating a
1419 new set. */
1420 save_aliasing_flag = flag_strict_aliasing;
1421 flag_strict_aliasing = 0;
1423 rtl = DECL_RTL (decl);
1424 /* Reset DECL_RTL back, as various parts of the compiler expects
1425 DECL_RTL set meaning it is actually going to be output. */
1426 SET_DECL_RTL (decl, NULL);
1428 flag_strict_aliasing = save_aliasing_flag;
1429 return rtl;
1432 /* Output a string of literal assembler code
1433 for an `asm' keyword used between functions. */
1435 void
1436 assemble_asm (tree string)
1438 const char *p;
1439 app_enable ();
1441 if (TREE_CODE (string) == ADDR_EXPR)
1442 string = TREE_OPERAND (string, 0);
1444 p = TREE_STRING_POINTER (string);
1445 fprintf (asm_out_file, "%s%s\n", p[0] == '\t' ? "" : "\t", p);
1448 /* Write the address of the entity given by SYMBOL to SEC. */
1449 void
1450 assemble_addr_to_section (rtx symbol, section *sec)
1452 switch_to_section (sec);
1453 assemble_align (POINTER_SIZE);
1454 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1457 /* Return the numbered .ctors.N (if CONSTRUCTOR_P) or .dtors.N (if
1458 not) section for PRIORITY. */
1459 section *
1460 get_cdtor_priority_section (int priority, bool constructor_p)
1462 char buf[16];
1464 /* ??? This only works reliably with the GNU linker. */
1465 sprintf (buf, "%s.%.5u",
1466 constructor_p ? ".ctors" : ".dtors",
1467 /* Invert the numbering so the linker puts us in the proper
1468 order; constructors are run from right to left, and the
1469 linker sorts in increasing order. */
1470 MAX_INIT_PRIORITY - priority);
1471 return get_section (buf, SECTION_WRITE, NULL);
1474 void
1475 default_named_section_asm_out_destructor (rtx symbol, int priority)
1477 section *sec;
1479 if (priority != DEFAULT_INIT_PRIORITY)
1480 sec = get_cdtor_priority_section (priority,
1481 /*constructor_p=*/false);
1482 else
1483 sec = get_section (".dtors", SECTION_WRITE, NULL);
1485 assemble_addr_to_section (symbol, sec);
1488 #ifdef DTORS_SECTION_ASM_OP
1489 void
1490 default_dtor_section_asm_out_destructor (rtx symbol,
1491 int priority ATTRIBUTE_UNUSED)
1493 assemble_addr_to_section (symbol, dtors_section);
1495 #endif
1497 void
1498 default_named_section_asm_out_constructor (rtx symbol, int priority)
1500 section *sec;
1502 if (priority != DEFAULT_INIT_PRIORITY)
1503 sec = get_cdtor_priority_section (priority,
1504 /*constructor_p=*/true);
1505 else
1506 sec = get_section (".ctors", SECTION_WRITE, NULL);
1508 assemble_addr_to_section (symbol, sec);
1511 #ifdef CTORS_SECTION_ASM_OP
1512 void
1513 default_ctor_section_asm_out_constructor (rtx symbol,
1514 int priority ATTRIBUTE_UNUSED)
1516 assemble_addr_to_section (symbol, ctors_section);
1518 #endif
1520 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1521 a nonzero value if the constant pool should be output before the
1522 start of the function, or a zero value if the pool should output
1523 after the end of the function. The default is to put it before the
1524 start. */
1526 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1527 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1528 #endif
1530 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1531 to be output to assembler.
1532 Set first_global_object_name and weak_global_object_name as appropriate. */
1534 void
1535 notice_global_symbol (tree decl)
1537 const char **type = &first_global_object_name;
1539 if (first_global_object_name
1540 || !TREE_PUBLIC (decl)
1541 || DECL_EXTERNAL (decl)
1542 || !DECL_NAME (decl)
1543 || (TREE_CODE (decl) != FUNCTION_DECL
1544 && (TREE_CODE (decl) != VAR_DECL
1545 || (DECL_COMMON (decl)
1546 && (DECL_INITIAL (decl) == 0
1547 || DECL_INITIAL (decl) == error_mark_node))))
1548 || !MEM_P (DECL_RTL (decl)))
1549 return;
1551 /* We win when global object is found, but it is useful to know about weak
1552 symbol as well so we can produce nicer unique names. */
1553 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl) || flag_shlib)
1554 type = &weak_global_object_name;
1556 if (!*type)
1558 const char *p;
1559 const char *name;
1560 rtx decl_rtl = DECL_RTL (decl);
1562 p = targetm.strip_name_encoding (XSTR (XEXP (decl_rtl, 0), 0));
1563 name = ggc_strdup (p);
1565 *type = name;
1569 /* If not using flag_reorder_blocks_and_partition, decide early whether the
1570 current function goes into the cold section, so that targets can use
1571 current_function_section during RTL expansion. DECL describes the
1572 function. */
1574 void
1575 decide_function_section (tree decl)
1577 first_function_block_is_cold = false;
1579 if (flag_reorder_blocks_and_partition)
1580 /* We will decide in assemble_start_function. */
1581 return;
1583 if (DECL_SECTION_NAME (decl))
1585 struct cgraph_node *node = cgraph_get_node (current_function_decl);
1586 /* Calls to function_section rely on first_function_block_is_cold
1587 being accurate. */
1588 first_function_block_is_cold = (node
1589 && node->frequency
1590 == NODE_FREQUENCY_UNLIKELY_EXECUTED);
1593 in_cold_section_p = first_function_block_is_cold;
1596 /* Output assembler code for the constant pool of a function and associated
1597 with defining the name of the function. DECL describes the function.
1598 NAME is the function's name. For the constant pool, we use the current
1599 constant pool data. */
1601 void
1602 assemble_start_function (tree decl, const char *fnname)
1604 int align;
1605 char tmp_label[100];
1606 bool hot_label_written = false;
1608 if (flag_reorder_blocks_and_partition)
1610 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTB", const_labelno);
1611 crtl->subsections.hot_section_label = ggc_strdup (tmp_label);
1612 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDB", const_labelno);
1613 crtl->subsections.cold_section_label = ggc_strdup (tmp_label);
1614 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTE", const_labelno);
1615 crtl->subsections.hot_section_end_label = ggc_strdup (tmp_label);
1616 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDE", const_labelno);
1617 crtl->subsections.cold_section_end_label = ggc_strdup (tmp_label);
1618 const_labelno++;
1620 else
1622 crtl->subsections.hot_section_label = NULL;
1623 crtl->subsections.cold_section_label = NULL;
1624 crtl->subsections.hot_section_end_label = NULL;
1625 crtl->subsections.cold_section_end_label = NULL;
1628 /* The following code does not need preprocessing in the assembler. */
1630 app_disable ();
1632 if (CONSTANT_POOL_BEFORE_FUNCTION)
1633 output_constant_pool (fnname, decl);
1635 /* Make sure the not and cold text (code) sections are properly
1636 aligned. This is necessary here in the case where the function
1637 has both hot and cold sections, because we don't want to re-set
1638 the alignment when the section switch happens mid-function. */
1640 if (flag_reorder_blocks_and_partition)
1642 first_function_block_is_cold = false;
1644 switch_to_section (unlikely_text_section ());
1645 assemble_align (DECL_ALIGN (decl));
1646 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_label);
1648 /* When the function starts with a cold section, we need to explicitly
1649 align the hot section and write out the hot section label.
1650 But if the current function is a thunk, we do not have a CFG. */
1651 if (!cfun->is_thunk
1652 && BB_PARTITION (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) == BB_COLD_PARTITION)
1654 switch_to_section (text_section);
1655 assemble_align (DECL_ALIGN (decl));
1656 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1657 hot_label_written = true;
1658 first_function_block_is_cold = true;
1660 in_cold_section_p = first_function_block_is_cold;
1664 /* Switch to the correct text section for the start of the function. */
1666 switch_to_section (function_section (decl));
1667 if (flag_reorder_blocks_and_partition
1668 && !hot_label_written)
1669 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1671 /* Tell assembler to move to target machine's alignment for functions. */
1672 align = floor_log2 (DECL_ALIGN (decl) / BITS_PER_UNIT);
1673 if (align > 0)
1675 ASM_OUTPUT_ALIGN (asm_out_file, align);
1678 /* Handle a user-specified function alignment.
1679 Note that we still need to align to DECL_ALIGN, as above,
1680 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1681 if (! DECL_USER_ALIGN (decl)
1682 && align_functions_log > align
1683 && optimize_function_for_speed_p (cfun))
1685 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1686 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1687 align_functions_log, align_functions - 1);
1688 #else
1689 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1690 #endif
1693 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1694 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1695 #endif
1697 if (!DECL_IGNORED_P (decl))
1698 (*debug_hooks->begin_function) (decl);
1700 /* Make function name accessible from other files, if appropriate. */
1702 if (TREE_PUBLIC (decl))
1704 notice_global_symbol (decl);
1706 globalize_decl (decl);
1708 maybe_assemble_visibility (decl);
1711 if (DECL_PRESERVE_P (decl))
1712 targetm.asm_out.mark_decl_preserved (fnname);
1714 /* Do any machine/system dependent processing of the function name. */
1715 #ifdef ASM_DECLARE_FUNCTION_NAME
1716 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1717 #else
1718 /* Standard thing is just output label for the function. */
1719 ASM_OUTPUT_FUNCTION_LABEL (asm_out_file, fnname, current_function_decl);
1720 #endif /* ASM_DECLARE_FUNCTION_NAME */
1722 if (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (decl)))
1723 saw_no_split_stack = true;
1726 /* Output assembler code associated with defining the size of the
1727 function. DECL describes the function. NAME is the function's name. */
1729 void
1730 assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED)
1732 #ifdef ASM_DECLARE_FUNCTION_SIZE
1733 /* We could have switched section in the middle of the function. */
1734 if (flag_reorder_blocks_and_partition)
1735 switch_to_section (function_section (decl));
1736 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1737 #endif
1738 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1740 output_constant_pool (fnname, decl);
1741 switch_to_section (function_section (decl)); /* need to switch back */
1743 /* Output labels for end of hot/cold text sections (to be used by
1744 debug info.) */
1745 if (flag_reorder_blocks_and_partition)
1747 section *save_text_section;
1749 save_text_section = in_section;
1750 switch_to_section (unlikely_text_section ());
1751 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label);
1752 if (first_function_block_is_cold)
1753 switch_to_section (text_section);
1754 else
1755 switch_to_section (function_section (decl));
1756 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label);
1757 switch_to_section (save_text_section);
1761 /* Assemble code to leave SIZE bytes of zeros. */
1763 void
1764 assemble_zeros (unsigned HOST_WIDE_INT size)
1766 /* Do no output if -fsyntax-only. */
1767 if (flag_syntax_only)
1768 return;
1770 #ifdef ASM_NO_SKIP_IN_TEXT
1771 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1772 so we must output 0s explicitly in the text section. */
1773 if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0)
1775 unsigned HOST_WIDE_INT i;
1776 for (i = 0; i < size; i++)
1777 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1779 else
1780 #endif
1781 if (size > 0)
1782 ASM_OUTPUT_SKIP (asm_out_file, size);
1785 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1787 void
1788 assemble_align (int align)
1790 if (align > BITS_PER_UNIT)
1792 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1796 /* Assemble a string constant with the specified C string as contents. */
1798 void
1799 assemble_string (const char *p, int size)
1801 int pos = 0;
1802 int maximum = 2000;
1804 /* If the string is very long, split it up. */
1806 while (pos < size)
1808 int thissize = size - pos;
1809 if (thissize > maximum)
1810 thissize = maximum;
1812 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1814 pos += thissize;
1815 p += thissize;
1820 /* A noswitch_section_callback for lcomm_section. */
1822 static bool
1823 emit_local (tree decl ATTRIBUTE_UNUSED,
1824 const char *name ATTRIBUTE_UNUSED,
1825 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1826 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1828 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1829 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name,
1830 size, DECL_ALIGN (decl));
1831 return true;
1832 #elif defined ASM_OUTPUT_ALIGNED_LOCAL
1833 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, DECL_ALIGN (decl));
1834 return true;
1835 #else
1836 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1837 return false;
1838 #endif
1841 /* A noswitch_section_callback for bss_noswitch_section. */
1843 #if defined ASM_OUTPUT_ALIGNED_BSS
1844 static bool
1845 emit_bss (tree decl ATTRIBUTE_UNUSED,
1846 const char *name ATTRIBUTE_UNUSED,
1847 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1848 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1850 #if defined ASM_OUTPUT_ALIGNED_BSS
1851 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size,
1852 get_variable_align (decl));
1853 return true;
1854 #endif
1856 #endif
1858 /* A noswitch_section_callback for comm_section. */
1860 static bool
1861 emit_common (tree decl ATTRIBUTE_UNUSED,
1862 const char *name ATTRIBUTE_UNUSED,
1863 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1864 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1866 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1867 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name,
1868 size, get_variable_align (decl));
1869 return true;
1870 #elif defined ASM_OUTPUT_ALIGNED_COMMON
1871 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size,
1872 get_variable_align (decl));
1873 return true;
1874 #else
1875 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
1876 return false;
1877 #endif
1880 /* A noswitch_section_callback for tls_comm_section. */
1882 static bool
1883 emit_tls_common (tree decl ATTRIBUTE_UNUSED,
1884 const char *name ATTRIBUTE_UNUSED,
1885 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1886 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1888 #ifdef ASM_OUTPUT_TLS_COMMON
1889 ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size);
1890 return true;
1891 #else
1892 sorry ("thread-local COMMON data not implemented");
1893 return true;
1894 #endif
1897 /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT.
1898 NAME is the name of DECL's SYMBOL_REF. */
1900 static void
1901 assemble_noswitch_variable (tree decl, const char *name, section *sect,
1902 unsigned int align)
1904 unsigned HOST_WIDE_INT size, rounded;
1906 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
1907 rounded = size;
1909 if ((flag_sanitize & SANITIZE_ADDRESS) && asan_protect_global (decl))
1910 size += asan_red_zone_size (size);
1912 /* Don't allocate zero bytes of common,
1913 since that means "undefined external" in the linker. */
1914 if (size == 0)
1915 rounded = 1;
1917 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1918 so that each uninitialized object starts on such a boundary. */
1919 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
1920 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1921 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1923 if (!sect->noswitch.callback (decl, name, size, rounded)
1924 && (unsigned HOST_WIDE_INT) (align / BITS_PER_UNIT) > rounded)
1925 error ("requested alignment for %q+D is greater than "
1926 "implemented alignment of %wu", decl, rounded);
1929 /* A subroutine of assemble_variable. Output the label and contents of
1930 DECL, whose address is a SYMBOL_REF with name NAME. DONT_OUTPUT_DATA
1931 is as for assemble_variable. */
1933 static void
1934 assemble_variable_contents (tree decl, const char *name,
1935 bool dont_output_data)
1937 /* Do any machine/system dependent processing of the object. */
1938 #ifdef ASM_DECLARE_OBJECT_NAME
1939 last_assemble_variable_decl = decl;
1940 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
1941 #else
1942 /* Standard thing is just output label for the object. */
1943 ASM_OUTPUT_LABEL (asm_out_file, name);
1944 #endif /* ASM_DECLARE_OBJECT_NAME */
1946 if (!dont_output_data)
1948 if (DECL_INITIAL (decl)
1949 && DECL_INITIAL (decl) != error_mark_node
1950 && !initializer_zerop (DECL_INITIAL (decl)))
1951 /* Output the actual data. */
1952 output_constant (DECL_INITIAL (decl),
1953 tree_to_uhwi (DECL_SIZE_UNIT (decl)),
1954 get_variable_align (decl));
1955 else
1956 /* Leave space for it. */
1957 assemble_zeros (tree_to_uhwi (DECL_SIZE_UNIT (decl)));
1961 /* Assemble everything that is needed for a variable or function declaration.
1962 Not used for automatic variables, and not used for function definitions.
1963 Should not be called for variables of incomplete structure type.
1965 TOP_LEVEL is nonzero if this variable has file scope.
1966 AT_END is nonzero if this is the special handling, at end of compilation,
1967 to define things that have had only tentative definitions.
1968 DONT_OUTPUT_DATA if nonzero means don't actually output the
1969 initial value (that will be done by the caller). */
1971 void
1972 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
1973 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
1975 const char *name;
1976 rtx decl_rtl, symbol;
1977 section *sect;
1978 unsigned int align;
1979 bool asan_protected = false;
1981 /* This function is supposed to handle VARIABLES. Ensure we have one. */
1982 gcc_assert (TREE_CODE (decl) == VAR_DECL);
1984 /* Emulated TLS had better not get this far. */
1985 gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl));
1987 last_assemble_variable_decl = 0;
1989 /* Normally no need to say anything here for external references,
1990 since assemble_external is called by the language-specific code
1991 when a declaration is first seen. */
1993 if (DECL_EXTERNAL (decl))
1994 return;
1996 /* Do nothing for global register variables. */
1997 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
1999 TREE_ASM_WRITTEN (decl) = 1;
2000 return;
2003 /* If type was incomplete when the variable was declared,
2004 see if it is complete now. */
2006 if (DECL_SIZE (decl) == 0)
2007 layout_decl (decl, 0);
2009 /* Still incomplete => don't allocate it; treat the tentative defn
2010 (which is what it must have been) as an `extern' reference. */
2012 if (!dont_output_data && DECL_SIZE (decl) == 0)
2014 error ("storage size of %q+D isn%'t known", decl);
2015 TREE_ASM_WRITTEN (decl) = 1;
2016 return;
2019 /* The first declaration of a variable that comes through this function
2020 decides whether it is global (in C, has external linkage)
2021 or local (in C, has internal linkage). So do nothing more
2022 if this function has already run. */
2024 if (TREE_ASM_WRITTEN (decl))
2025 return;
2027 /* Make sure targetm.encode_section_info is invoked before we set
2028 ASM_WRITTEN. */
2029 decl_rtl = DECL_RTL (decl);
2031 TREE_ASM_WRITTEN (decl) = 1;
2033 /* Do no output if -fsyntax-only. */
2034 if (flag_syntax_only)
2035 return;
2037 if (! dont_output_data
2038 && ! valid_constant_size_p (DECL_SIZE_UNIT (decl)))
2040 error ("size of variable %q+D is too large", decl);
2041 return;
2044 gcc_assert (MEM_P (decl_rtl));
2045 gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF);
2046 symbol = XEXP (decl_rtl, 0);
2048 /* If this symbol belongs to the tree constant pool, output the constant
2049 if it hasn't already been written. */
2050 if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
2052 tree decl = SYMBOL_REF_DECL (symbol);
2053 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
2054 output_constant_def_contents (symbol);
2055 return;
2058 app_disable ();
2060 name = XSTR (symbol, 0);
2061 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
2062 notice_global_symbol (decl);
2064 /* Compute the alignment of this data. */
2066 align_variable (decl, dont_output_data);
2068 if ((flag_sanitize & SANITIZE_ADDRESS)
2069 && asan_protect_global (decl))
2071 asan_protected = true;
2072 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
2073 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
2076 set_mem_align (decl_rtl, DECL_ALIGN (decl));
2078 align = get_variable_align (decl);
2080 if (TREE_PUBLIC (decl))
2081 maybe_assemble_visibility (decl);
2083 if (DECL_PRESERVE_P (decl))
2084 targetm.asm_out.mark_decl_preserved (name);
2086 /* First make the assembler name(s) global if appropriate. */
2087 sect = get_variable_section (decl, false);
2088 if (TREE_PUBLIC (decl)
2089 && (sect->common.flags & SECTION_COMMON) == 0)
2090 globalize_decl (decl);
2092 /* Output any data that we will need to use the address of. */
2093 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
2094 output_addressed_constants (DECL_INITIAL (decl));
2096 /* dbxout.c needs to know this. */
2097 if (sect && (sect->common.flags & SECTION_CODE) != 0)
2098 DECL_IN_TEXT_SECTION (decl) = 1;
2100 /* If the decl is part of an object_block, make sure that the decl
2101 has been positioned within its block, but do not write out its
2102 definition yet. output_object_blocks will do that later. */
2103 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
2105 gcc_assert (!dont_output_data);
2106 place_block_symbol (symbol);
2108 else if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
2109 assemble_noswitch_variable (decl, name, sect, align);
2110 else
2112 /* The following bit of code ensures that vtable_map
2113 variables are not only in the comdat section, but that
2114 each variable has its own unique comdat name. If this
2115 code is removed, the variables end up in the same section
2116 with a single comdat name.
2118 FIXME: resolve_unique_section needs to deal better with
2119 decls with both DECL_SECTION_NAME and DECL_ONE_ONLY. Once
2120 that is fixed, this if-else statement can be replaced with
2121 a single call to "switch_to_section (sect)". */
2122 if (sect->named.name
2123 && (strcmp (sect->named.name, ".vtable_map_vars") == 0))
2125 #if defined (OBJECT_FORMAT_ELF)
2126 targetm.asm_out.named_section (sect->named.name,
2127 sect->named.common.flags
2128 | SECTION_LINKONCE,
2129 DECL_NAME (decl));
2130 in_section = sect;
2131 #else
2132 switch_to_section (sect);
2133 #endif
2135 else
2136 switch_to_section (sect);
2137 if (align > BITS_PER_UNIT)
2138 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2139 assemble_variable_contents (decl, name, dont_output_data);
2140 if (asan_protected)
2142 unsigned HOST_WIDE_INT int size
2143 = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2144 assemble_zeros (asan_red_zone_size (size));
2150 /* Given a function declaration (FN_DECL), this function assembles the
2151 function into the .preinit_array section. */
2153 void
2154 assemble_vtv_preinit_initializer (tree fn_decl)
2156 section *sect;
2157 unsigned flags = SECTION_WRITE;
2158 rtx symbol = XEXP (DECL_RTL (fn_decl), 0);
2160 flags |= SECTION_NOTYPE;
2161 sect = get_section (".preinit_array", flags, fn_decl);
2162 switch_to_section (sect);
2163 assemble_addr_to_section (symbol, sect);
2166 /* Return 1 if type TYPE contains any pointers. */
2168 static int
2169 contains_pointers_p (tree type)
2171 switch (TREE_CODE (type))
2173 case POINTER_TYPE:
2174 case REFERENCE_TYPE:
2175 /* I'm not sure whether OFFSET_TYPE needs this treatment,
2176 so I'll play safe and return 1. */
2177 case OFFSET_TYPE:
2178 return 1;
2180 case RECORD_TYPE:
2181 case UNION_TYPE:
2182 case QUAL_UNION_TYPE:
2184 tree fields;
2185 /* For a type that has fields, see if the fields have pointers. */
2186 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2187 if (TREE_CODE (fields) == FIELD_DECL
2188 && contains_pointers_p (TREE_TYPE (fields)))
2189 return 1;
2190 return 0;
2193 case ARRAY_TYPE:
2194 /* An array type contains pointers if its element type does. */
2195 return contains_pointers_p (TREE_TYPE (type));
2197 default:
2198 return 0;
2202 /* We delay assemble_external processing until
2203 the compilation unit is finalized. This is the best we can do for
2204 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2205 it all the way to final. See PR 17982 for further discussion. */
2206 static GTY(()) tree pending_assemble_externals;
2208 #ifdef ASM_OUTPUT_EXTERNAL
2209 /* Some targets delay some output to final using TARGET_ASM_FILE_END.
2210 As a result, assemble_external can be called after the list of externals
2211 is processed and the pointer set destroyed. */
2212 static bool pending_assemble_externals_processed;
2214 /* Avoid O(external_decls**2) lookups in the pending_assemble_externals
2215 TREE_LIST in assemble_external. */
2216 static struct pointer_set_t *pending_assemble_externals_set;
2218 /* True if DECL is a function decl for which no out-of-line copy exists.
2219 It is assumed that DECL's assembler name has been set. */
2221 static bool
2222 incorporeal_function_p (tree decl)
2224 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
2226 const char *name;
2228 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2229 && (DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA
2230 || DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA_WITH_ALIGN))
2231 return true;
2233 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2234 /* Atomic or sync builtins which have survived this far will be
2235 resolved externally and therefore are not incorporeal. */
2236 if (strncmp (name, "__builtin_", 10) == 0)
2237 return true;
2239 return false;
2242 /* Actually do the tests to determine if this is necessary, and invoke
2243 ASM_OUTPUT_EXTERNAL. */
2244 static void
2245 assemble_external_real (tree decl)
2247 rtx rtl = DECL_RTL (decl);
2249 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2250 && !SYMBOL_REF_USED (XEXP (rtl, 0))
2251 && !incorporeal_function_p (decl))
2253 /* Some systems do require some output. */
2254 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2255 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2258 #endif
2260 void
2261 process_pending_assemble_externals (void)
2263 #ifdef ASM_OUTPUT_EXTERNAL
2264 tree list;
2265 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2266 assemble_external_real (TREE_VALUE (list));
2268 pending_assemble_externals = 0;
2269 pending_assemble_externals_processed = true;
2270 pointer_set_destroy (pending_assemble_externals_set);
2271 #endif
2274 /* This TREE_LIST contains any weak symbol declarations waiting
2275 to be emitted. */
2276 static GTY(()) tree weak_decls;
2278 /* Output something to declare an external symbol to the assembler,
2279 and qualifiers such as weakness. (Most assemblers don't need
2280 extern declaration, so we normally output nothing.) Do nothing if
2281 DECL is not external. */
2283 void
2284 assemble_external (tree decl ATTRIBUTE_UNUSED)
2286 /* Make sure that the ASM_OUT_FILE is open.
2287 If it's not, we should not be calling this function. */
2288 gcc_assert (asm_out_file);
2290 /* In a perfect world, the following condition would be true.
2291 Sadly, the Java and Go front ends emit assembly *from the front end*,
2292 bypassing the call graph. See PR52739. Fix before GCC 4.8. */
2293 #if 0
2294 /* This function should only be called if we are expanding, or have
2295 expanded, to RTL.
2296 Ideally, only final.c would be calling this function, but it is
2297 not clear whether that would break things somehow. See PR 17982
2298 for further discussion. */
2299 gcc_assert (cgraph_state == CGRAPH_STATE_EXPANSION
2300 || cgraph_state == CGRAPH_STATE_FINISHED);
2301 #endif
2303 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2304 return;
2306 /* We want to output annotation for weak and external symbols at
2307 very last to check if they are references or not. */
2309 if (TARGET_SUPPORTS_WEAK
2310 && DECL_WEAK (decl)
2311 /* TREE_STATIC is a weird and abused creature which is not
2312 generally the right test for whether an entity has been
2313 locally emitted, inlined or otherwise not-really-extern, but
2314 for declarations that can be weak, it happens to be
2315 match. */
2316 && !TREE_STATIC (decl)
2317 && lookup_attribute ("weak", DECL_ATTRIBUTES (decl))
2318 && value_member (decl, weak_decls) == NULL_TREE)
2319 weak_decls = tree_cons (NULL, decl, weak_decls);
2321 #ifdef ASM_OUTPUT_EXTERNAL
2322 if (pending_assemble_externals_processed)
2324 assemble_external_real (decl);
2325 return;
2328 if (! pointer_set_insert (pending_assemble_externals_set, decl))
2329 pending_assemble_externals = tree_cons (NULL, decl,
2330 pending_assemble_externals);
2331 #endif
2334 /* Similar, for calling a library function FUN. */
2336 void
2337 assemble_external_libcall (rtx fun)
2339 /* Declare library function name external when first used, if nec. */
2340 if (! SYMBOL_REF_USED (fun))
2342 SYMBOL_REF_USED (fun) = 1;
2343 targetm.asm_out.external_libcall (fun);
2347 /* Assemble a label named NAME. */
2349 void
2350 assemble_label (FILE *file, const char *name)
2352 ASM_OUTPUT_LABEL (file, name);
2355 /* Set the symbol_referenced flag for ID. */
2356 void
2357 mark_referenced (tree id)
2359 TREE_SYMBOL_REFERENCED (id) = 1;
2362 /* Set the symbol_referenced flag for DECL and notify callgraph. */
2363 void
2364 mark_decl_referenced (tree decl)
2366 if (TREE_CODE (decl) == FUNCTION_DECL)
2368 /* Extern inline functions don't become needed when referenced.
2369 If we know a method will be emitted in other TU and no new
2370 functions can be marked reachable, just use the external
2371 definition. */
2372 struct cgraph_node *node = cgraph_get_create_node (decl);
2373 if (!DECL_EXTERNAL (decl)
2374 && !node->definition)
2375 cgraph_mark_force_output_node (node);
2377 else if (TREE_CODE (decl) == VAR_DECL)
2379 varpool_node *node = varpool_node_for_decl (decl);
2380 /* C++ frontend use mark_decl_references to force COMDAT variables
2381 to be output that might appear dead otherwise. */
2382 node->force_output = true;
2384 /* else do nothing - we can get various sorts of CST nodes here,
2385 which do not need to be marked. */
2389 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS
2390 until we find an identifier that is not itself a transparent alias.
2391 Modify the alias passed to it by reference (and all aliases on the
2392 way to the ultimate target), such that they do not have to be
2393 followed again, and return the ultimate target of the alias
2394 chain. */
2396 static inline tree
2397 ultimate_transparent_alias_target (tree *alias)
2399 tree target = *alias;
2401 if (IDENTIFIER_TRANSPARENT_ALIAS (target))
2403 gcc_assert (TREE_CHAIN (target));
2404 target = ultimate_transparent_alias_target (&TREE_CHAIN (target));
2405 gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target)
2406 && ! TREE_CHAIN (target));
2407 *alias = target;
2410 return target;
2413 /* Output to FILE (an assembly file) a reference to NAME. If NAME
2414 starts with a *, the rest of NAME is output verbatim. Otherwise
2415 NAME is transformed in a target-specific way (usually by the
2416 addition of an underscore). */
2418 void
2419 assemble_name_raw (FILE *file, const char *name)
2421 if (name[0] == '*')
2422 fputs (&name[1], file);
2423 else
2424 ASM_OUTPUT_LABELREF (file, name);
2427 /* Like assemble_name_raw, but should be used when NAME might refer to
2428 an entity that is also represented as a tree (like a function or
2429 variable). If NAME does refer to such an entity, that entity will
2430 be marked as referenced. */
2432 void
2433 assemble_name (FILE *file, const char *name)
2435 const char *real_name;
2436 tree id;
2438 real_name = targetm.strip_name_encoding (name);
2440 id = maybe_get_identifier (real_name);
2441 if (id)
2443 tree id_orig = id;
2445 mark_referenced (id);
2446 ultimate_transparent_alias_target (&id);
2447 if (id != id_orig)
2448 name = IDENTIFIER_POINTER (id);
2449 gcc_assert (! TREE_CHAIN (id));
2452 assemble_name_raw (file, name);
2455 /* Allocate SIZE bytes writable static space with a gensym name
2456 and return an RTX to refer to its address. */
2459 assemble_static_space (unsigned HOST_WIDE_INT size)
2461 char name[12];
2462 const char *namestring;
2463 rtx x;
2465 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2466 ++const_labelno;
2467 namestring = ggc_strdup (name);
2469 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2470 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2472 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2473 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2474 BIGGEST_ALIGNMENT);
2475 #else
2476 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2477 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2478 #else
2480 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2481 so that each uninitialized object starts on such a boundary. */
2482 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2483 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2484 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2485 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2486 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2487 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2489 #endif
2490 #endif
2491 return x;
2494 /* Assemble the static constant template for function entry trampolines.
2495 This is done at most once per compilation.
2496 Returns an RTX for the address of the template. */
2498 static GTY(()) rtx initial_trampoline;
2501 assemble_trampoline_template (void)
2503 char label[256];
2504 const char *name;
2505 int align;
2506 rtx symbol;
2508 gcc_assert (targetm.asm_out.trampoline_template != NULL);
2510 if (initial_trampoline)
2511 return initial_trampoline;
2513 /* By default, put trampoline templates in read-only data section. */
2515 #ifdef TRAMPOLINE_SECTION
2516 switch_to_section (TRAMPOLINE_SECTION);
2517 #else
2518 switch_to_section (readonly_data_section);
2519 #endif
2521 /* Write the assembler code to define one. */
2522 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2523 if (align > 0)
2524 ASM_OUTPUT_ALIGN (asm_out_file, align);
2526 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2527 targetm.asm_out.trampoline_template (asm_out_file);
2529 /* Record the rtl to refer to it. */
2530 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2531 name = ggc_strdup (label);
2532 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2533 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2535 initial_trampoline = gen_const_mem (BLKmode, symbol);
2536 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2537 set_mem_size (initial_trampoline, TRAMPOLINE_SIZE);
2539 return initial_trampoline;
2542 /* A and B are either alignments or offsets. Return the minimum alignment
2543 that may be assumed after adding the two together. */
2545 static inline unsigned
2546 min_align (unsigned int a, unsigned int b)
2548 return (a | b) & -(a | b);
2551 /* Return the assembler directive for creating a given kind of integer
2552 object. SIZE is the number of bytes in the object and ALIGNED_P
2553 indicates whether it is known to be aligned. Return NULL if the
2554 assembly dialect has no such directive.
2556 The returned string should be printed at the start of a new line and
2557 be followed immediately by the object's initial value. */
2559 const char *
2560 integer_asm_op (int size, int aligned_p)
2562 struct asm_int_op *ops;
2564 if (aligned_p)
2565 ops = &targetm.asm_out.aligned_op;
2566 else
2567 ops = &targetm.asm_out.unaligned_op;
2569 switch (size)
2571 case 1:
2572 return targetm.asm_out.byte_op;
2573 case 2:
2574 return ops->hi;
2575 case 4:
2576 return ops->si;
2577 case 8:
2578 return ops->di;
2579 case 16:
2580 return ops->ti;
2581 default:
2582 return NULL;
2586 /* Use directive OP to assemble an integer object X. Print OP at the
2587 start of the line, followed immediately by the value of X. */
2589 void
2590 assemble_integer_with_op (const char *op, rtx x)
2592 fputs (op, asm_out_file);
2593 output_addr_const (asm_out_file, x);
2594 fputc ('\n', asm_out_file);
2597 /* The default implementation of the asm_out.integer target hook. */
2599 bool
2600 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2601 unsigned int size ATTRIBUTE_UNUSED,
2602 int aligned_p ATTRIBUTE_UNUSED)
2604 const char *op = integer_asm_op (size, aligned_p);
2605 /* Avoid GAS bugs for large values. Specifically negative values whose
2606 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2607 if (size > UNITS_PER_WORD && size > POINTER_SIZE / BITS_PER_UNIT)
2608 return false;
2609 return op && (assemble_integer_with_op (op, x), true);
2612 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2613 the alignment of the integer in bits. Return 1 if we were able to output
2614 the constant, otherwise 0. We must be able to output the constant,
2615 if FORCE is nonzero. */
2617 bool
2618 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2620 int aligned_p;
2622 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2624 /* See if the target hook can handle this kind of object. */
2625 if (targetm.asm_out.integer (x, size, aligned_p))
2626 return true;
2628 /* If the object is a multi-byte one, try splitting it up. Split
2629 it into words it if is multi-word, otherwise split it into bytes. */
2630 if (size > 1)
2632 enum machine_mode omode, imode;
2633 unsigned int subalign;
2634 unsigned int subsize, i;
2635 enum mode_class mclass;
2637 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2638 subalign = MIN (align, subsize * BITS_PER_UNIT);
2639 if (GET_CODE (x) == CONST_FIXED)
2640 mclass = GET_MODE_CLASS (GET_MODE (x));
2641 else
2642 mclass = MODE_INT;
2644 omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0);
2645 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0);
2647 for (i = 0; i < size; i += subsize)
2649 rtx partial = simplify_subreg (omode, x, imode, i);
2650 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2651 break;
2653 if (i == size)
2654 return true;
2656 /* If we've printed some of it, but not all of it, there's no going
2657 back now. */
2658 gcc_assert (!i);
2661 gcc_assert (!force);
2663 return false;
2666 void
2667 assemble_real (REAL_VALUE_TYPE d, enum machine_mode mode, unsigned int align)
2669 long data[4] = {0, 0, 0, 0};
2670 int i;
2671 int bitsize, nelts, nunits, units_per;
2673 /* This is hairy. We have a quantity of known size. real_to_target
2674 will put it into an array of *host* longs, 32 bits per element
2675 (even if long is more than 32 bits). We need to determine the
2676 number of array elements that are occupied (nelts) and the number
2677 of *target* min-addressable units that will be occupied in the
2678 object file (nunits). We cannot assume that 32 divides the
2679 mode's bitsize (size * BITS_PER_UNIT) evenly.
2681 size * BITS_PER_UNIT is used here to make sure that padding bits
2682 (which might appear at either end of the value; real_to_target
2683 will include the padding bits in its output array) are included. */
2685 nunits = GET_MODE_SIZE (mode);
2686 bitsize = nunits * BITS_PER_UNIT;
2687 nelts = CEIL (bitsize, 32);
2688 units_per = 32 / BITS_PER_UNIT;
2690 real_to_target (data, &d, mode);
2692 /* Put out the first word with the specified alignment. */
2693 assemble_integer (GEN_INT (data[0]), MIN (nunits, units_per), align, 1);
2694 nunits -= units_per;
2696 /* Subsequent words need only 32-bit alignment. */
2697 align = min_align (align, 32);
2699 for (i = 1; i < nelts; i++)
2701 assemble_integer (GEN_INT (data[i]), MIN (nunits, units_per), align, 1);
2702 nunits -= units_per;
2706 /* Given an expression EXP with a constant value,
2707 reduce it to the sum of an assembler symbol and an integer.
2708 Store them both in the structure *VALUE.
2709 EXP must be reducible. */
2711 struct addr_const {
2712 rtx base;
2713 HOST_WIDE_INT offset;
2716 static void
2717 decode_addr_const (tree exp, struct addr_const *value)
2719 tree target = TREE_OPERAND (exp, 0);
2720 int offset = 0;
2721 rtx x;
2723 while (1)
2725 if (TREE_CODE (target) == COMPONENT_REF
2726 && tree_fits_shwi_p (byte_position (TREE_OPERAND (target, 1))))
2728 offset += int_byte_position (TREE_OPERAND (target, 1));
2729 target = TREE_OPERAND (target, 0);
2731 else if (TREE_CODE (target) == ARRAY_REF
2732 || TREE_CODE (target) == ARRAY_RANGE_REF)
2734 offset += (tree_to_uhwi (TYPE_SIZE_UNIT (TREE_TYPE (target)))
2735 * tree_to_shwi (TREE_OPERAND (target, 1)));
2736 target = TREE_OPERAND (target, 0);
2738 else if (TREE_CODE (target) == MEM_REF
2739 && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR)
2741 offset += mem_ref_offset (target).low;
2742 target = TREE_OPERAND (TREE_OPERAND (target, 0), 0);
2744 else if (TREE_CODE (target) == INDIRECT_REF
2745 && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR
2746 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0))
2747 == ADDR_EXPR)
2748 target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0);
2749 else
2750 break;
2753 switch (TREE_CODE (target))
2755 case VAR_DECL:
2756 case FUNCTION_DECL:
2757 x = DECL_RTL (target);
2758 break;
2760 case LABEL_DECL:
2761 x = gen_rtx_MEM (FUNCTION_MODE,
2762 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2763 break;
2765 case REAL_CST:
2766 case FIXED_CST:
2767 case STRING_CST:
2768 case COMPLEX_CST:
2769 case CONSTRUCTOR:
2770 case INTEGER_CST:
2771 x = output_constant_def (target, 1);
2772 break;
2774 default:
2775 gcc_unreachable ();
2778 gcc_assert (MEM_P (x));
2779 x = XEXP (x, 0);
2781 value->base = x;
2782 value->offset = offset;
2786 static GTY((param_is (struct constant_descriptor_tree)))
2787 htab_t const_desc_htab;
2789 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2791 /* Constant pool accessor function. */
2793 htab_t
2794 constant_pool_htab (void)
2796 return const_desc_htab;
2799 /* Compute a hash code for a constant expression. */
2801 static hashval_t
2802 const_desc_hash (const void *ptr)
2804 return ((const struct constant_descriptor_tree *)ptr)->hash;
2807 static hashval_t
2808 const_hash_1 (const tree exp)
2810 const char *p;
2811 hashval_t hi;
2812 int len, i;
2813 enum tree_code code = TREE_CODE (exp);
2815 /* Either set P and LEN to the address and len of something to hash and
2816 exit the switch or return a value. */
2818 switch (code)
2820 case INTEGER_CST:
2821 p = (char *) &TREE_INT_CST (exp);
2822 len = sizeof TREE_INT_CST (exp);
2823 break;
2825 case REAL_CST:
2826 return real_hash (TREE_REAL_CST_PTR (exp));
2828 case FIXED_CST:
2829 return fixed_hash (TREE_FIXED_CST_PTR (exp));
2831 case STRING_CST:
2832 p = TREE_STRING_POINTER (exp);
2833 len = TREE_STRING_LENGTH (exp);
2834 break;
2836 case COMPLEX_CST:
2837 return (const_hash_1 (TREE_REALPART (exp)) * 5
2838 + const_hash_1 (TREE_IMAGPART (exp)));
2840 case VECTOR_CST:
2842 unsigned i;
2844 hi = 7 + VECTOR_CST_NELTS (exp);
2846 for (i = 0; i < VECTOR_CST_NELTS (exp); ++i)
2847 hi = hi * 563 + const_hash_1 (VECTOR_CST_ELT (exp, i));
2849 return hi;
2852 case CONSTRUCTOR:
2854 unsigned HOST_WIDE_INT idx;
2855 tree value;
2857 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2859 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
2860 if (value)
2861 hi = hi * 603 + const_hash_1 (value);
2863 return hi;
2866 case ADDR_EXPR:
2867 case FDESC_EXPR:
2869 struct addr_const value;
2871 decode_addr_const (exp, &value);
2872 switch (GET_CODE (value.base))
2874 case SYMBOL_REF:
2875 /* Don't hash the address of the SYMBOL_REF;
2876 only use the offset and the symbol name. */
2877 hi = value.offset;
2878 p = XSTR (value.base, 0);
2879 for (i = 0; p[i] != 0; i++)
2880 hi = ((hi * 613) + (unsigned) (p[i]));
2881 break;
2883 case LABEL_REF:
2884 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13;
2885 break;
2887 default:
2888 gcc_unreachable ();
2891 return hi;
2893 case PLUS_EXPR:
2894 case POINTER_PLUS_EXPR:
2895 case MINUS_EXPR:
2896 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2897 + const_hash_1 (TREE_OPERAND (exp, 1)));
2899 CASE_CONVERT:
2900 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
2902 default:
2903 /* A language specific constant. Just hash the code. */
2904 return code;
2907 /* Compute hashing function. */
2908 hi = len;
2909 for (i = 0; i < len; i++)
2910 hi = ((hi * 613) + (unsigned) (p[i]));
2912 return hi;
2915 /* Wrapper of compare_constant, for the htab interface. */
2916 static int
2917 const_desc_eq (const void *p1, const void *p2)
2919 const struct constant_descriptor_tree *const c1
2920 = (const struct constant_descriptor_tree *) p1;
2921 const struct constant_descriptor_tree *const c2
2922 = (const struct constant_descriptor_tree *) p2;
2923 if (c1->hash != c2->hash)
2924 return 0;
2925 return compare_constant (c1->value, c2->value);
2928 /* Compare t1 and t2, and return 1 only if they are known to result in
2929 the same bit pattern on output. */
2931 static int
2932 compare_constant (const tree t1, const tree t2)
2934 enum tree_code typecode;
2936 if (t1 == NULL_TREE)
2937 return t2 == NULL_TREE;
2938 if (t2 == NULL_TREE)
2939 return 0;
2941 if (TREE_CODE (t1) != TREE_CODE (t2))
2942 return 0;
2944 switch (TREE_CODE (t1))
2946 case INTEGER_CST:
2947 /* Integer constants are the same only if the same width of type. */
2948 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2949 return 0;
2950 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2951 return 0;
2952 return tree_int_cst_equal (t1, t2);
2954 case REAL_CST:
2955 /* Real constants are the same only if the same width of type. */
2956 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2957 return 0;
2959 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
2961 case FIXED_CST:
2962 /* Fixed constants are the same only if the same width of type. */
2963 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2964 return 0;
2966 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
2968 case STRING_CST:
2969 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2970 return 0;
2972 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
2973 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
2974 TREE_STRING_LENGTH (t1)));
2976 case COMPLEX_CST:
2977 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
2978 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
2980 case VECTOR_CST:
2982 unsigned i;
2984 if (VECTOR_CST_NELTS (t1) != VECTOR_CST_NELTS (t2))
2985 return 0;
2987 for (i = 0; i < VECTOR_CST_NELTS (t1); ++i)
2988 if (!compare_constant (VECTOR_CST_ELT (t1, i),
2989 VECTOR_CST_ELT (t2, i)))
2990 return 0;
2992 return 1;
2995 case CONSTRUCTOR:
2997 vec<constructor_elt, va_gc> *v1, *v2;
2998 unsigned HOST_WIDE_INT idx;
3000 typecode = TREE_CODE (TREE_TYPE (t1));
3001 if (typecode != TREE_CODE (TREE_TYPE (t2)))
3002 return 0;
3004 if (typecode == ARRAY_TYPE)
3006 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
3007 /* For arrays, check that the sizes all match. */
3008 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
3009 || size_1 == -1
3010 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
3011 return 0;
3013 else
3015 /* For record and union constructors, require exact type
3016 equality. */
3017 if (TREE_TYPE (t1) != TREE_TYPE (t2))
3018 return 0;
3021 v1 = CONSTRUCTOR_ELTS (t1);
3022 v2 = CONSTRUCTOR_ELTS (t2);
3023 if (vec_safe_length (v1) != vec_safe_length (v2))
3024 return 0;
3026 for (idx = 0; idx < vec_safe_length (v1); ++idx)
3028 constructor_elt *c1 = &(*v1)[idx];
3029 constructor_elt *c2 = &(*v2)[idx];
3031 /* Check that each value is the same... */
3032 if (!compare_constant (c1->value, c2->value))
3033 return 0;
3034 /* ... and that they apply to the same fields! */
3035 if (typecode == ARRAY_TYPE)
3037 if (!compare_constant (c1->index, c2->index))
3038 return 0;
3040 else
3042 if (c1->index != c2->index)
3043 return 0;
3047 return 1;
3050 case ADDR_EXPR:
3051 case FDESC_EXPR:
3053 struct addr_const value1, value2;
3054 enum rtx_code code;
3055 int ret;
3057 decode_addr_const (t1, &value1);
3058 decode_addr_const (t2, &value2);
3060 if (value1.offset != value2.offset)
3061 return 0;
3063 code = GET_CODE (value1.base);
3064 if (code != GET_CODE (value2.base))
3065 return 0;
3067 switch (code)
3069 case SYMBOL_REF:
3070 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3071 break;
3073 case LABEL_REF:
3074 ret = (CODE_LABEL_NUMBER (XEXP (value1.base, 0))
3075 == CODE_LABEL_NUMBER (XEXP (value2.base, 0)));
3076 break;
3078 default:
3079 gcc_unreachable ();
3081 return ret;
3084 case PLUS_EXPR:
3085 case POINTER_PLUS_EXPR:
3086 case MINUS_EXPR:
3087 case RANGE_EXPR:
3088 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3089 && compare_constant (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3091 CASE_CONVERT:
3092 case VIEW_CONVERT_EXPR:
3093 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3095 default:
3096 return 0;
3099 gcc_unreachable ();
3102 /* Make a copy of the whole tree structure for a constant. This
3103 handles the same types of nodes that compare_constant handles. */
3105 static tree
3106 copy_constant (tree exp)
3108 switch (TREE_CODE (exp))
3110 case ADDR_EXPR:
3111 /* For ADDR_EXPR, we do not want to copy the decl whose address
3112 is requested. We do want to copy constants though. */
3113 if (CONSTANT_CLASS_P (TREE_OPERAND (exp, 0)))
3114 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
3115 copy_constant (TREE_OPERAND (exp, 0)));
3116 else
3117 return copy_node (exp);
3119 case INTEGER_CST:
3120 case REAL_CST:
3121 case FIXED_CST:
3122 case STRING_CST:
3123 return copy_node (exp);
3125 case COMPLEX_CST:
3126 return build_complex (TREE_TYPE (exp),
3127 copy_constant (TREE_REALPART (exp)),
3128 copy_constant (TREE_IMAGPART (exp)));
3130 case PLUS_EXPR:
3131 case POINTER_PLUS_EXPR:
3132 case MINUS_EXPR:
3133 return build2 (TREE_CODE (exp), TREE_TYPE (exp),
3134 copy_constant (TREE_OPERAND (exp, 0)),
3135 copy_constant (TREE_OPERAND (exp, 1)));
3137 CASE_CONVERT:
3138 case VIEW_CONVERT_EXPR:
3139 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
3140 copy_constant (TREE_OPERAND (exp, 0)));
3142 case VECTOR_CST:
3143 return build_vector (TREE_TYPE (exp), VECTOR_CST_ELTS (exp));
3145 case CONSTRUCTOR:
3147 tree copy = copy_node (exp);
3148 vec<constructor_elt, va_gc> *v;
3149 unsigned HOST_WIDE_INT idx;
3150 tree purpose, value;
3152 vec_alloc (v, vec_safe_length (CONSTRUCTOR_ELTS (exp)));
3153 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (exp), idx, purpose, value)
3155 constructor_elt ce = {purpose, copy_constant (value)};
3156 v->quick_push (ce);
3158 CONSTRUCTOR_ELTS (copy) = v;
3159 return copy;
3162 default:
3163 gcc_unreachable ();
3167 /* Return the section into which constant EXP should be placed. */
3169 static section *
3170 get_constant_section (tree exp, unsigned int align)
3172 return targetm.asm_out.select_section (exp,
3173 compute_reloc_for_constant (exp),
3174 align);
3177 /* Return the size of constant EXP in bytes. */
3179 static HOST_WIDE_INT
3180 get_constant_size (tree exp)
3182 HOST_WIDE_INT size;
3184 size = int_size_in_bytes (TREE_TYPE (exp));
3185 if (TREE_CODE (exp) == STRING_CST)
3186 size = MAX (TREE_STRING_LENGTH (exp), size);
3187 return size;
3190 /* Subroutine of output_constant_def:
3191 No constant equal to EXP is known to have been output.
3192 Make a constant descriptor to enter EXP in the hash table.
3193 Assign the label number and construct RTL to refer to the
3194 constant's location in memory.
3195 Caller is responsible for updating the hash table. */
3197 static struct constant_descriptor_tree *
3198 build_constant_desc (tree exp)
3200 struct constant_descriptor_tree *desc;
3201 rtx symbol, rtl;
3202 char label[256];
3203 int labelno;
3204 tree decl;
3206 desc = ggc_alloc_constant_descriptor_tree ();
3207 desc->value = copy_constant (exp);
3209 /* Create a string containing the label name, in LABEL. */
3210 labelno = const_labelno++;
3211 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3213 /* Construct the VAR_DECL associated with the constant. */
3214 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3215 TREE_TYPE (exp));
3216 DECL_ARTIFICIAL (decl) = 1;
3217 DECL_IGNORED_P (decl) = 1;
3218 TREE_READONLY (decl) = 1;
3219 TREE_STATIC (decl) = 1;
3220 TREE_ADDRESSABLE (decl) = 1;
3221 /* We don't set the RTL yet as this would cause varpool to assume that the
3222 variable is referenced. Moreover, it would just be dropped in LTO mode.
3223 Instead we set the flag that will be recognized in make_decl_rtl. */
3224 DECL_IN_CONSTANT_POOL (decl) = 1;
3225 DECL_INITIAL (decl) = desc->value;
3226 /* ??? CONSTANT_ALIGNMENT hasn't been updated for vector types on most
3227 architectures so use DATA_ALIGNMENT as well, except for strings. */
3228 if (TREE_CODE (exp) == STRING_CST)
3230 #ifdef CONSTANT_ALIGNMENT
3231 DECL_ALIGN (decl) = CONSTANT_ALIGNMENT (exp, DECL_ALIGN (decl));
3232 #endif
3234 else
3235 align_variable (decl, 0);
3237 /* Now construct the SYMBOL_REF and the MEM. */
3238 if (use_object_blocks_p ())
3240 section *sect = get_constant_section (exp, DECL_ALIGN (decl));
3241 symbol = create_block_symbol (ggc_strdup (label),
3242 get_block_for_section (sect), -1);
3244 else
3245 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3246 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3247 SET_SYMBOL_REF_DECL (symbol, decl);
3248 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3250 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3251 set_mem_attributes (rtl, exp, 1);
3252 set_mem_alias_set (rtl, 0);
3253 set_mem_alias_set (rtl, const_alias_set);
3255 /* We cannot share RTX'es in pool entries.
3256 Mark this piece of RTL as required for unsharing. */
3257 RTX_FLAG (rtl, used) = 1;
3259 /* Set flags or add text to the name to record information, such as
3260 that it is a local symbol. If the name is changed, the macro
3261 ASM_OUTPUT_LABELREF will have to know how to strip this
3262 information. This call might invalidate our local variable
3263 SYMBOL; we can't use it afterward. */
3264 targetm.encode_section_info (exp, rtl, true);
3266 desc->rtl = rtl;
3268 return desc;
3271 /* Return an rtx representing a reference to constant data in memory
3272 for the constant expression EXP.
3274 If assembler code for such a constant has already been output,
3275 return an rtx to refer to it.
3276 Otherwise, output such a constant in memory
3277 and generate an rtx for it.
3279 If DEFER is nonzero, this constant can be deferred and output only
3280 if referenced in the function after all optimizations.
3282 `const_desc_table' records which constants already have label strings. */
3285 output_constant_def (tree exp, int defer)
3287 struct constant_descriptor_tree *desc;
3288 struct constant_descriptor_tree key;
3289 void **loc;
3291 /* Look up EXP in the table of constant descriptors. If we didn't find
3292 it, create a new one. */
3293 key.value = exp;
3294 key.hash = const_hash_1 (exp);
3295 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3297 desc = (struct constant_descriptor_tree *) *loc;
3298 if (desc == 0)
3300 desc = build_constant_desc (exp);
3301 desc->hash = key.hash;
3302 *loc = desc;
3305 maybe_output_constant_def_contents (desc, defer);
3306 return desc->rtl;
3309 /* Subroutine of output_constant_def: Decide whether or not we need to
3310 output the constant DESC now, and if so, do it. */
3311 static void
3312 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3313 int defer)
3315 rtx symbol = XEXP (desc->rtl, 0);
3316 tree exp = desc->value;
3318 if (flag_syntax_only)
3319 return;
3321 if (TREE_ASM_WRITTEN (exp))
3322 /* Already output; don't do it again. */
3323 return;
3325 /* We can always defer constants as long as the context allows
3326 doing so. */
3327 if (defer)
3329 /* Increment n_deferred_constants if it exists. It needs to be at
3330 least as large as the number of constants actually referred to
3331 by the function. If it's too small we'll stop looking too early
3332 and fail to emit constants; if it's too large we'll only look
3333 through the entire function when we could have stopped earlier. */
3334 if (cfun)
3335 n_deferred_constants++;
3336 return;
3339 output_constant_def_contents (symbol);
3342 /* Subroutine of output_constant_def_contents. Output the definition
3343 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3344 constant's alignment in bits. */
3346 static void
3347 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3349 HOST_WIDE_INT size;
3351 size = get_constant_size (exp);
3353 /* Do any machine/system dependent processing of the constant. */
3354 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3356 /* Output the value of EXP. */
3357 output_constant (exp, size, align);
3360 /* We must output the constant data referred to by SYMBOL; do so. */
3362 static void
3363 output_constant_def_contents (rtx symbol)
3365 tree decl = SYMBOL_REF_DECL (symbol);
3366 tree exp = DECL_INITIAL (decl);
3367 unsigned int align;
3368 bool asan_protected = false;
3370 /* Make sure any other constants whose addresses appear in EXP
3371 are assigned label numbers. */
3372 output_addressed_constants (exp);
3374 /* We are no longer deferring this constant. */
3375 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3377 if ((flag_sanitize & SANITIZE_ADDRESS)
3378 && TREE_CODE (exp) == STRING_CST
3379 && asan_protect_global (exp))
3381 asan_protected = true;
3382 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
3383 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
3386 /* If the constant is part of an object block, make sure that the
3387 decl has been positioned within its block, but do not write out
3388 its definition yet. output_object_blocks will do that later. */
3389 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3390 place_block_symbol (symbol);
3391 else
3393 align = DECL_ALIGN (decl);
3394 switch_to_section (get_constant_section (exp, align));
3395 if (align > BITS_PER_UNIT)
3396 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3397 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3398 if (asan_protected)
3400 HOST_WIDE_INT size = get_constant_size (exp);
3401 assemble_zeros (asan_red_zone_size (size));
3406 /* Look up EXP in the table of constant descriptors. Return the rtl
3407 if it has been emitted, else null. */
3410 lookup_constant_def (tree exp)
3412 struct constant_descriptor_tree *desc;
3413 struct constant_descriptor_tree key;
3415 key.value = exp;
3416 key.hash = const_hash_1 (exp);
3417 desc = (struct constant_descriptor_tree *)
3418 htab_find_with_hash (const_desc_htab, &key, key.hash);
3420 return (desc ? desc->rtl : NULL_RTX);
3423 /* Return a tree representing a reference to constant data in memory
3424 for the constant expression EXP.
3426 This is the counterpart of output_constant_def at the Tree level. */
3428 tree
3429 tree_output_constant_def (tree exp)
3431 struct constant_descriptor_tree *desc, key;
3432 void **loc;
3433 tree decl;
3435 /* Look up EXP in the table of constant descriptors. If we didn't find
3436 it, create a new one. */
3437 key.value = exp;
3438 key.hash = const_hash_1 (exp);
3439 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3441 desc = (struct constant_descriptor_tree *) *loc;
3442 if (desc == 0)
3444 desc = build_constant_desc (exp);
3445 desc->hash = key.hash;
3446 *loc = desc;
3449 decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3450 varpool_finalize_decl (decl);
3451 return decl;
3454 /* Used in the hash tables to avoid outputting the same constant
3455 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3456 are output once per function, not once per file. */
3457 /* ??? Only a few targets need per-function constant pools. Most
3458 can use one per-file pool. Should add a targetm bit to tell the
3459 difference. */
3461 struct GTY(()) rtx_constant_pool {
3462 /* Pointers to first and last constant in pool, as ordered by offset. */
3463 struct constant_descriptor_rtx *first;
3464 struct constant_descriptor_rtx *last;
3466 /* Hash facility for making memory-constants from constant rtl-expressions.
3467 It is used on RISC machines where immediate integer arguments and
3468 constant addresses are restricted so that such constants must be stored
3469 in memory. */
3470 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_htab;
3472 /* Current offset in constant pool (does not include any
3473 machine-specific header). */
3474 HOST_WIDE_INT offset;
3477 struct GTY((chain_next ("%h.next"))) constant_descriptor_rtx {
3478 struct constant_descriptor_rtx *next;
3479 rtx mem;
3480 rtx sym;
3481 rtx constant;
3482 HOST_WIDE_INT offset;
3483 hashval_t hash;
3484 enum machine_mode mode;
3485 unsigned int align;
3486 int labelno;
3487 int mark;
3490 /* Hash and compare functions for const_rtx_htab. */
3492 static hashval_t
3493 const_desc_rtx_hash (const void *ptr)
3495 const struct constant_descriptor_rtx *const desc
3496 = (const struct constant_descriptor_rtx *) ptr;
3497 return desc->hash;
3500 static int
3501 const_desc_rtx_eq (const void *a, const void *b)
3503 const struct constant_descriptor_rtx *const x
3504 = (const struct constant_descriptor_rtx *) a;
3505 const struct constant_descriptor_rtx *const y
3506 = (const struct constant_descriptor_rtx *) b;
3508 if (x->mode != y->mode)
3509 return 0;
3510 return rtx_equal_p (x->constant, y->constant);
3513 /* This is the worker function for const_rtx_hash, called via for_each_rtx. */
3515 static int
3516 const_rtx_hash_1 (rtx *xp, void *data)
3518 unsigned HOST_WIDE_INT hwi;
3519 enum machine_mode mode;
3520 enum rtx_code code;
3521 hashval_t h, *hp;
3522 rtx x;
3524 x = *xp;
3525 code = GET_CODE (x);
3526 mode = GET_MODE (x);
3527 h = (hashval_t) code * 1048573 + mode;
3529 switch (code)
3531 case CONST_INT:
3532 hwi = INTVAL (x);
3533 fold_hwi:
3535 int shift = sizeof (hashval_t) * CHAR_BIT;
3536 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3537 int i;
3539 h ^= (hashval_t) hwi;
3540 for (i = 1; i < n; ++i)
3542 hwi >>= shift;
3543 h ^= (hashval_t) hwi;
3546 break;
3548 case CONST_DOUBLE:
3549 if (mode == VOIDmode)
3551 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3552 goto fold_hwi;
3554 else
3555 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3556 break;
3558 case CONST_FIXED:
3559 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3560 break;
3562 case CONST_VECTOR:
3564 int i;
3565 for (i = XVECLEN (x, 0); i-- > 0; )
3566 h = h * 251 + const_rtx_hash_1 (&XVECEXP (x, 0, i), data);
3568 break;
3570 case SYMBOL_REF:
3571 h ^= htab_hash_string (XSTR (x, 0));
3572 break;
3574 case LABEL_REF:
3575 h = h * 251 + CODE_LABEL_NUMBER (XEXP (x, 0));
3576 break;
3578 case UNSPEC:
3579 case UNSPEC_VOLATILE:
3580 h = h * 251 + XINT (x, 1);
3581 break;
3583 default:
3584 break;
3587 hp = (hashval_t *) data;
3588 *hp = *hp * 509 + h;
3589 return 0;
3592 /* Compute a hash value for X, which should be a constant. */
3594 static hashval_t
3595 const_rtx_hash (rtx x)
3597 hashval_t h = 0;
3598 for_each_rtx (&x, const_rtx_hash_1, &h);
3599 return h;
3603 /* Create and return a new rtx constant pool. */
3605 static struct rtx_constant_pool *
3606 create_constant_pool (void)
3608 struct rtx_constant_pool *pool;
3610 pool = ggc_alloc_rtx_constant_pool ();
3611 pool->const_rtx_htab = htab_create_ggc (31, const_desc_rtx_hash,
3612 const_desc_rtx_eq, NULL);
3613 pool->first = NULL;
3614 pool->last = NULL;
3615 pool->offset = 0;
3616 return pool;
3619 /* Initialize constant pool hashing for a new function. */
3621 void
3622 init_varasm_status (void)
3624 crtl->varasm.pool = create_constant_pool ();
3625 crtl->varasm.deferred_constants = 0;
3628 /* Given a MINUS expression, simplify it if both sides
3629 include the same symbol. */
3632 simplify_subtraction (rtx x)
3634 rtx r = simplify_rtx (x);
3635 return r ? r : x;
3638 /* Given a constant rtx X, make (or find) a memory constant for its value
3639 and return a MEM rtx to refer to it in memory. */
3642 force_const_mem (enum machine_mode mode, rtx x)
3644 struct constant_descriptor_rtx *desc, tmp;
3645 struct rtx_constant_pool *pool;
3646 char label[256];
3647 rtx def, symbol;
3648 hashval_t hash;
3649 unsigned int align;
3650 void **slot;
3652 /* If we're not allowed to drop X into the constant pool, don't. */
3653 if (targetm.cannot_force_const_mem (mode, x))
3654 return NULL_RTX;
3656 /* Record that this function has used a constant pool entry. */
3657 crtl->uses_const_pool = 1;
3659 /* Decide which pool to use. */
3660 pool = (targetm.use_blocks_for_constant_p (mode, x)
3661 ? shared_constant_pool
3662 : crtl->varasm.pool);
3664 /* Lookup the value in the hashtable. */
3665 tmp.constant = x;
3666 tmp.mode = mode;
3667 hash = const_rtx_hash (x);
3668 slot = htab_find_slot_with_hash (pool->const_rtx_htab, &tmp, hash, INSERT);
3669 desc = (struct constant_descriptor_rtx *) *slot;
3671 /* If the constant was already present, return its memory. */
3672 if (desc)
3673 return copy_rtx (desc->mem);
3675 /* Otherwise, create a new descriptor. */
3676 desc = ggc_alloc_constant_descriptor_rtx ();
3677 *slot = desc;
3679 /* Align the location counter as required by EXP's data type. */
3680 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3681 #ifdef CONSTANT_ALIGNMENT
3683 tree type = lang_hooks.types.type_for_mode (mode, 0);
3684 if (type != NULL_TREE)
3685 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3687 #endif
3689 pool->offset += (align / BITS_PER_UNIT) - 1;
3690 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3692 desc->next = NULL;
3693 desc->constant = copy_rtx (tmp.constant);
3694 desc->offset = pool->offset;
3695 desc->hash = hash;
3696 desc->mode = mode;
3697 desc->align = align;
3698 desc->labelno = const_labelno;
3699 desc->mark = 0;
3701 pool->offset += GET_MODE_SIZE (mode);
3702 if (pool->last)
3703 pool->last->next = desc;
3704 else
3705 pool->first = pool->last = desc;
3706 pool->last = desc;
3708 /* Create a string containing the label name, in LABEL. */
3709 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3710 ++const_labelno;
3712 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3713 the constants pool. */
3714 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3716 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3717 symbol = create_block_symbol (ggc_strdup (label),
3718 get_block_for_section (sect), -1);
3720 else
3721 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3722 desc->sym = symbol;
3723 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3724 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3725 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3727 /* Construct the MEM. */
3728 desc->mem = def = gen_const_mem (mode, symbol);
3729 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3730 set_mem_align (def, align);
3732 /* If we're dropping a label to the constant pool, make sure we
3733 don't delete it. */
3734 if (GET_CODE (x) == LABEL_REF)
3735 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3737 return copy_rtx (def);
3740 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3743 get_pool_constant (rtx addr)
3745 return SYMBOL_REF_CONSTANT (addr)->constant;
3748 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3749 and whether it has been output or not. */
3752 get_pool_constant_mark (rtx addr, bool *pmarked)
3754 struct constant_descriptor_rtx *desc;
3756 desc = SYMBOL_REF_CONSTANT (addr);
3757 *pmarked = (desc->mark != 0);
3758 return desc->constant;
3761 /* Similar, return the mode. */
3763 enum machine_mode
3764 get_pool_mode (const_rtx addr)
3766 return SYMBOL_REF_CONSTANT (addr)->mode;
3769 /* Return the size of the constant pool. */
3772 get_pool_size (void)
3774 return crtl->varasm.pool->offset;
3777 /* Worker function for output_constant_pool_1. Emit assembly for X
3778 in MODE with known alignment ALIGN. */
3780 static void
3781 output_constant_pool_2 (enum machine_mode mode, rtx x, unsigned int align)
3783 switch (GET_MODE_CLASS (mode))
3785 case MODE_FLOAT:
3786 case MODE_DECIMAL_FLOAT:
3788 REAL_VALUE_TYPE r;
3790 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3791 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3792 assemble_real (r, mode, align);
3793 break;
3796 case MODE_INT:
3797 case MODE_PARTIAL_INT:
3798 case MODE_FRACT:
3799 case MODE_UFRACT:
3800 case MODE_ACCUM:
3801 case MODE_UACCUM:
3802 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3803 break;
3805 case MODE_VECTOR_FLOAT:
3806 case MODE_VECTOR_INT:
3807 case MODE_VECTOR_FRACT:
3808 case MODE_VECTOR_UFRACT:
3809 case MODE_VECTOR_ACCUM:
3810 case MODE_VECTOR_UACCUM:
3812 int i, units;
3813 enum machine_mode submode = GET_MODE_INNER (mode);
3814 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3816 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3817 units = CONST_VECTOR_NUNITS (x);
3819 for (i = 0; i < units; i++)
3821 rtx elt = CONST_VECTOR_ELT (x, i);
3822 output_constant_pool_2 (submode, elt, i ? subalign : align);
3825 break;
3827 default:
3828 gcc_unreachable ();
3832 /* Worker function for output_constant_pool. Emit constant DESC,
3833 giving it ALIGN bits of alignment. */
3835 static void
3836 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3837 unsigned int align)
3839 rtx x, tmp;
3841 x = desc->constant;
3843 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3844 whose CODE_LABEL has been deleted. This can occur if a jump table
3845 is eliminated by optimization. If so, write a constant of zero
3846 instead. Note that this can also happen by turning the
3847 CODE_LABEL into a NOTE. */
3848 /* ??? This seems completely and utterly wrong. Certainly it's
3849 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3850 functioning even with INSN_DELETED_P and friends. */
3852 tmp = x;
3853 switch (GET_CODE (tmp))
3855 case CONST:
3856 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3857 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
3858 break;
3859 tmp = XEXP (XEXP (tmp, 0), 0);
3860 /* FALLTHRU */
3862 case LABEL_REF:
3863 tmp = XEXP (tmp, 0);
3864 gcc_assert (!INSN_DELETED_P (tmp));
3865 gcc_assert (!NOTE_P (tmp)
3866 || NOTE_KIND (tmp) != NOTE_INSN_DELETED);
3867 break;
3869 default:
3870 break;
3873 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3874 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3875 align, desc->labelno, done);
3876 #endif
3878 assemble_align (align);
3880 /* Output the label. */
3881 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3883 /* Output the data. */
3884 output_constant_pool_2 (desc->mode, x, align);
3886 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3887 sections have proper size. */
3888 if (align > GET_MODE_BITSIZE (desc->mode)
3889 && in_section
3890 && (in_section->common.flags & SECTION_MERGE))
3891 assemble_align (align);
3893 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3894 done:
3895 #endif
3896 return;
3899 /* Given a SYMBOL_REF CURRENT_RTX, mark it and all constants it refers
3900 to as used. Emit referenced deferred strings. This function can
3901 be used with for_each_rtx to mark all SYMBOL_REFs in an rtx. */
3903 static int
3904 mark_constant (rtx *current_rtx, void *data ATTRIBUTE_UNUSED)
3906 rtx x = *current_rtx;
3908 if (x == NULL_RTX || GET_CODE (x) != SYMBOL_REF)
3909 return 0;
3911 if (CONSTANT_POOL_ADDRESS_P (x))
3913 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
3914 if (desc->mark == 0)
3916 desc->mark = 1;
3917 for_each_rtx (&desc->constant, mark_constant, NULL);
3920 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3922 tree decl = SYMBOL_REF_DECL (x);
3923 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
3925 n_deferred_constants--;
3926 output_constant_def_contents (x);
3930 return -1;
3933 /* Look through appropriate parts of INSN, marking all entries in the
3934 constant pool which are actually being used. Entries that are only
3935 referenced by other constants are also marked as used. Emit
3936 deferred strings that are used. */
3938 static void
3939 mark_constants (rtx insn)
3941 if (!INSN_P (insn))
3942 return;
3944 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3945 insns, not any notes that may be attached. We don't want to mark
3946 a constant just because it happens to appear in a REG_EQUIV note. */
3947 if (GET_CODE (PATTERN (insn)) == SEQUENCE)
3949 rtx seq = PATTERN (insn);
3950 int i, n = XVECLEN (seq, 0);
3951 for (i = 0; i < n; ++i)
3953 rtx subinsn = XVECEXP (seq, 0, i);
3954 if (INSN_P (subinsn))
3955 for_each_rtx (&PATTERN (subinsn), mark_constant, NULL);
3958 else
3959 for_each_rtx (&PATTERN (insn), mark_constant, NULL);
3962 /* Look through the instructions for this function, and mark all the
3963 entries in POOL which are actually being used. Emit deferred constants
3964 which have indeed been used. */
3966 static void
3967 mark_constant_pool (void)
3969 rtx insn;
3971 if (!crtl->uses_const_pool && n_deferred_constants == 0)
3972 return;
3974 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3975 mark_constants (insn);
3978 /* Write all the constants in POOL. */
3980 static void
3981 output_constant_pool_contents (struct rtx_constant_pool *pool)
3983 struct constant_descriptor_rtx *desc;
3985 for (desc = pool->first; desc ; desc = desc->next)
3986 if (desc->mark)
3988 /* If the constant is part of an object_block, make sure that
3989 the constant has been positioned within its block, but do not
3990 write out its definition yet. output_object_blocks will do
3991 that later. */
3992 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
3993 && SYMBOL_REF_BLOCK (desc->sym))
3994 place_block_symbol (desc->sym);
3995 else
3997 switch_to_section (targetm.asm_out.select_rtx_section
3998 (desc->mode, desc->constant, desc->align));
3999 output_constant_pool_1 (desc, desc->align);
4004 /* Mark all constants that are used in the current function, then write
4005 out the function's private constant pool. */
4007 static void
4008 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
4009 tree fndecl ATTRIBUTE_UNUSED)
4011 struct rtx_constant_pool *pool = crtl->varasm.pool;
4013 /* It is possible for gcc to call force_const_mem and then to later
4014 discard the instructions which refer to the constant. In such a
4015 case we do not need to output the constant. */
4016 mark_constant_pool ();
4018 #ifdef ASM_OUTPUT_POOL_PROLOGUE
4019 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
4020 #endif
4022 output_constant_pool_contents (pool);
4024 #ifdef ASM_OUTPUT_POOL_EPILOGUE
4025 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
4026 #endif
4029 /* Write the contents of the shared constant pool. */
4031 void
4032 output_shared_constant_pool (void)
4034 output_constant_pool_contents (shared_constant_pool);
4037 /* Determine what kind of relocations EXP may need. */
4040 compute_reloc_for_constant (tree exp)
4042 int reloc = 0, reloc2;
4043 tree tem;
4045 switch (TREE_CODE (exp))
4047 case ADDR_EXPR:
4048 case FDESC_EXPR:
4049 /* Go inside any operations that get_inner_reference can handle and see
4050 if what's inside is a constant: no need to do anything here for
4051 addresses of variables or functions. */
4052 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4053 tem = TREE_OPERAND (tem, 0))
4056 if (TREE_CODE (tem) == MEM_REF
4057 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4059 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4060 break;
4063 if (!targetm.binds_local_p (tem))
4064 reloc |= 2;
4065 else
4066 reloc |= 1;
4067 break;
4069 case PLUS_EXPR:
4070 case POINTER_PLUS_EXPR:
4071 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4072 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4073 break;
4075 case MINUS_EXPR:
4076 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4077 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4078 /* The difference of two local labels is computable at link time. */
4079 if (reloc == 1 && reloc2 == 1)
4080 reloc = 0;
4081 else
4082 reloc |= reloc2;
4083 break;
4085 CASE_CONVERT:
4086 case VIEW_CONVERT_EXPR:
4087 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4088 break;
4090 case CONSTRUCTOR:
4092 unsigned HOST_WIDE_INT idx;
4093 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4094 if (tem != 0)
4095 reloc |= compute_reloc_for_constant (tem);
4097 break;
4099 default:
4100 break;
4102 return reloc;
4105 /* Find all the constants whose addresses are referenced inside of EXP,
4106 and make sure assembler code with a label has been output for each one.
4107 Indicate whether an ADDR_EXPR has been encountered. */
4109 static void
4110 output_addressed_constants (tree exp)
4112 tree tem;
4114 switch (TREE_CODE (exp))
4116 case ADDR_EXPR:
4117 case FDESC_EXPR:
4118 /* Go inside any operations that get_inner_reference can handle and see
4119 if what's inside is a constant: no need to do anything here for
4120 addresses of variables or functions. */
4121 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4122 tem = TREE_OPERAND (tem, 0))
4125 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4126 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4127 tem = DECL_INITIAL (tem);
4129 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4130 output_constant_def (tem, 0);
4132 if (TREE_CODE (tem) == MEM_REF)
4133 output_addressed_constants (TREE_OPERAND (tem, 0));
4134 break;
4136 case PLUS_EXPR:
4137 case POINTER_PLUS_EXPR:
4138 case MINUS_EXPR:
4139 output_addressed_constants (TREE_OPERAND (exp, 1));
4140 /* Fall through. */
4142 CASE_CONVERT:
4143 case VIEW_CONVERT_EXPR:
4144 output_addressed_constants (TREE_OPERAND (exp, 0));
4145 break;
4147 case CONSTRUCTOR:
4149 unsigned HOST_WIDE_INT idx;
4150 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4151 if (tem != 0)
4152 output_addressed_constants (tem);
4154 break;
4156 default:
4157 break;
4161 /* Whether a constructor CTOR is a valid static constant initializer if all
4162 its elements are. This used to be internal to initializer_constant_valid_p
4163 and has been exposed to let other functions like categorize_ctor_elements
4164 evaluate the property while walking a constructor for other purposes. */
4166 bool
4167 constructor_static_from_elts_p (const_tree ctor)
4169 return (TREE_CONSTANT (ctor)
4170 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4171 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4172 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4175 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4176 tree *cache);
4178 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4179 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4180 which are valid when ENDTYPE is an integer of any size; in
4181 particular, this does not accept a pointer minus a constant. This
4182 returns null_pointer_node if the VALUE is an absolute constant
4183 which can be used to initialize a static variable. Otherwise it
4184 returns NULL. */
4186 static tree
4187 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4189 tree op0, op1;
4191 if (!INTEGRAL_TYPE_P (endtype))
4192 return NULL_TREE;
4194 op0 = TREE_OPERAND (value, 0);
4195 op1 = TREE_OPERAND (value, 1);
4197 /* Like STRIP_NOPS except allow the operand mode to widen. This
4198 works around a feature of fold that simplifies (int)(p1 - p2) to
4199 ((int)p1 - (int)p2) under the theory that the narrower operation
4200 is cheaper. */
4202 while (CONVERT_EXPR_P (op0)
4203 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4205 tree inner = TREE_OPERAND (op0, 0);
4206 if (inner == error_mark_node
4207 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4208 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
4209 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4210 break;
4211 op0 = inner;
4214 while (CONVERT_EXPR_P (op1)
4215 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4217 tree inner = TREE_OPERAND (op1, 0);
4218 if (inner == error_mark_node
4219 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4220 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
4221 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4222 break;
4223 op1 = inner;
4226 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4227 if (!op0)
4228 return NULL_TREE;
4230 op1 = initializer_constant_valid_p_1 (op1, endtype,
4231 cache ? cache + 2 : NULL);
4232 /* Both initializers must be known. */
4233 if (op1)
4235 if (op0 == op1
4236 && (op0 == null_pointer_node
4237 || TREE_CODE (value) == MINUS_EXPR))
4238 return null_pointer_node;
4240 /* Support differences between labels. */
4241 if (TREE_CODE (op0) == LABEL_DECL
4242 && TREE_CODE (op1) == LABEL_DECL)
4243 return null_pointer_node;
4245 if (TREE_CODE (op0) == STRING_CST
4246 && TREE_CODE (op1) == STRING_CST
4247 && operand_equal_p (op0, op1, 1))
4248 return null_pointer_node;
4251 return NULL_TREE;
4254 /* Helper function of initializer_constant_valid_p.
4255 Return nonzero if VALUE is a valid constant-valued expression
4256 for use in initializing a static variable; one that can be an
4257 element of a "constant" initializer.
4259 Return null_pointer_node if the value is absolute;
4260 if it is relocatable, return the variable that determines the relocation.
4261 We assume that VALUE has been folded as much as possible;
4262 therefore, we do not need to check for such things as
4263 arithmetic-combinations of integers.
4265 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4267 static tree
4268 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4270 tree ret;
4272 switch (TREE_CODE (value))
4274 case CONSTRUCTOR:
4275 if (constructor_static_from_elts_p (value))
4277 unsigned HOST_WIDE_INT idx;
4278 tree elt;
4279 bool absolute = true;
4281 if (cache && cache[0] == value)
4282 return cache[1];
4283 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4285 tree reloc;
4286 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4287 NULL);
4288 if (!reloc)
4290 if (cache)
4292 cache[0] = value;
4293 cache[1] = NULL_TREE;
4295 return NULL_TREE;
4297 if (reloc != null_pointer_node)
4298 absolute = false;
4300 /* For a non-absolute relocation, there is no single
4301 variable that can be "the variable that determines the
4302 relocation." */
4303 if (cache)
4305 cache[0] = value;
4306 cache[1] = absolute ? null_pointer_node : error_mark_node;
4308 return absolute ? null_pointer_node : error_mark_node;
4311 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4313 case INTEGER_CST:
4314 case VECTOR_CST:
4315 case REAL_CST:
4316 case FIXED_CST:
4317 case STRING_CST:
4318 case COMPLEX_CST:
4319 return null_pointer_node;
4321 case ADDR_EXPR:
4322 case FDESC_EXPR:
4324 tree op0 = staticp (TREE_OPERAND (value, 0));
4325 if (op0)
4327 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4328 to be a constant, this is old-skool offsetof-like nonsense. */
4329 if (TREE_CODE (op0) == INDIRECT_REF
4330 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4331 return null_pointer_node;
4332 /* Taking the address of a nested function involves a trampoline,
4333 unless we don't need or want one. */
4334 if (TREE_CODE (op0) == FUNCTION_DECL
4335 && DECL_STATIC_CHAIN (op0)
4336 && !TREE_NO_TRAMPOLINE (value))
4337 return NULL_TREE;
4338 /* "&{...}" requires a temporary to hold the constructed
4339 object. */
4340 if (TREE_CODE (op0) == CONSTRUCTOR)
4341 return NULL_TREE;
4343 return op0;
4346 case NON_LVALUE_EXPR:
4347 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4348 endtype, cache);
4350 case VIEW_CONVERT_EXPR:
4352 tree src = TREE_OPERAND (value, 0);
4353 tree src_type = TREE_TYPE (src);
4354 tree dest_type = TREE_TYPE (value);
4356 /* Allow view-conversions from aggregate to non-aggregate type only
4357 if the bit pattern is fully preserved afterwards; otherwise, the
4358 RTL expander won't be able to apply a subsequent transformation
4359 to the underlying constructor. */
4360 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4362 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4363 return initializer_constant_valid_p_1 (src, endtype, cache);
4364 else
4365 return NULL_TREE;
4368 /* Allow all other kinds of view-conversion. */
4369 return initializer_constant_valid_p_1 (src, endtype, cache);
4372 CASE_CONVERT:
4374 tree src = TREE_OPERAND (value, 0);
4375 tree src_type = TREE_TYPE (src);
4376 tree dest_type = TREE_TYPE (value);
4378 /* Allow conversions between pointer types, floating-point
4379 types, and offset types. */
4380 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4381 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4382 || (TREE_CODE (dest_type) == OFFSET_TYPE
4383 && TREE_CODE (src_type) == OFFSET_TYPE))
4384 return initializer_constant_valid_p_1 (src, endtype, cache);
4386 /* Allow length-preserving conversions between integer types. */
4387 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4388 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4389 return initializer_constant_valid_p_1 (src, endtype, cache);
4391 /* Allow conversions between other integer types only if
4392 explicit value. */
4393 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type))
4395 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4396 if (inner == null_pointer_node)
4397 return null_pointer_node;
4398 break;
4401 /* Allow (int) &foo provided int is as wide as a pointer. */
4402 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4403 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4404 return initializer_constant_valid_p_1 (src, endtype, cache);
4406 /* Likewise conversions from int to pointers, but also allow
4407 conversions from 0. */
4408 if ((POINTER_TYPE_P (dest_type)
4409 || TREE_CODE (dest_type) == OFFSET_TYPE)
4410 && INTEGRAL_TYPE_P (src_type))
4412 if (TREE_CODE (src) == INTEGER_CST
4413 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4414 return null_pointer_node;
4415 if (integer_zerop (src))
4416 return null_pointer_node;
4417 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4418 return initializer_constant_valid_p_1 (src, endtype, cache);
4421 /* Allow conversions to struct or union types if the value
4422 inside is okay. */
4423 if (TREE_CODE (dest_type) == RECORD_TYPE
4424 || TREE_CODE (dest_type) == UNION_TYPE)
4425 return initializer_constant_valid_p_1 (src, endtype, cache);
4427 break;
4429 case POINTER_PLUS_EXPR:
4430 case PLUS_EXPR:
4431 /* Any valid floating-point constants will have been folded by now;
4432 with -frounding-math we hit this with addition of two constants. */
4433 if (TREE_CODE (endtype) == REAL_TYPE)
4434 return NULL_TREE;
4435 if (cache && cache[0] == value)
4436 return cache[1];
4437 if (! INTEGRAL_TYPE_P (endtype)
4438 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4440 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4441 tree valid0
4442 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4443 endtype, ncache);
4444 tree valid1
4445 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4446 endtype, ncache + 2);
4447 /* If either term is absolute, use the other term's relocation. */
4448 if (valid0 == null_pointer_node)
4449 ret = valid1;
4450 else if (valid1 == null_pointer_node)
4451 ret = valid0;
4452 /* Support narrowing pointer differences. */
4453 else
4454 ret = narrowing_initializer_constant_valid_p (value, endtype,
4455 ncache);
4457 else
4458 /* Support narrowing pointer differences. */
4459 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4460 if (cache)
4462 cache[0] = value;
4463 cache[1] = ret;
4465 return ret;
4467 case MINUS_EXPR:
4468 if (TREE_CODE (endtype) == REAL_TYPE)
4469 return NULL_TREE;
4470 if (cache && cache[0] == value)
4471 return cache[1];
4472 if (! INTEGRAL_TYPE_P (endtype)
4473 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4475 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4476 tree valid0
4477 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4478 endtype, ncache);
4479 tree valid1
4480 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4481 endtype, ncache + 2);
4482 /* Win if second argument is absolute. */
4483 if (valid1 == null_pointer_node)
4484 ret = valid0;
4485 /* Win if both arguments have the same relocation.
4486 Then the value is absolute. */
4487 else if (valid0 == valid1 && valid0 != 0)
4488 ret = null_pointer_node;
4489 /* Since GCC guarantees that string constants are unique in the
4490 generated code, a subtraction between two copies of the same
4491 constant string is absolute. */
4492 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4493 && valid1 && TREE_CODE (valid1) == STRING_CST
4494 && operand_equal_p (valid0, valid1, 1))
4495 ret = null_pointer_node;
4496 /* Support narrowing differences. */
4497 else
4498 ret = narrowing_initializer_constant_valid_p (value, endtype,
4499 ncache);
4501 else
4502 /* Support narrowing differences. */
4503 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4504 if (cache)
4506 cache[0] = value;
4507 cache[1] = ret;
4509 return ret;
4511 default:
4512 break;
4515 return NULL_TREE;
4518 /* Return nonzero if VALUE is a valid constant-valued expression
4519 for use in initializing a static variable; one that can be an
4520 element of a "constant" initializer.
4522 Return null_pointer_node if the value is absolute;
4523 if it is relocatable, return the variable that determines the relocation.
4524 We assume that VALUE has been folded as much as possible;
4525 therefore, we do not need to check for such things as
4526 arithmetic-combinations of integers. */
4527 tree
4528 initializer_constant_valid_p (tree value, tree endtype)
4530 return initializer_constant_valid_p_1 (value, endtype, NULL);
4533 /* Return true if VALUE is a valid constant-valued expression
4534 for use in initializing a static bit-field; one that can be
4535 an element of a "constant" initializer. */
4537 bool
4538 initializer_constant_valid_for_bitfield_p (tree value)
4540 /* For bitfields we support integer constants or possibly nested aggregates
4541 of such. */
4542 switch (TREE_CODE (value))
4544 case CONSTRUCTOR:
4546 unsigned HOST_WIDE_INT idx;
4547 tree elt;
4549 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4550 if (!initializer_constant_valid_for_bitfield_p (elt))
4551 return false;
4552 return true;
4555 case INTEGER_CST:
4556 case REAL_CST:
4557 return true;
4559 case VIEW_CONVERT_EXPR:
4560 case NON_LVALUE_EXPR:
4561 return
4562 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4564 default:
4565 break;
4568 return false;
4571 /* output_constructor outer state of relevance in recursive calls, typically
4572 for nested aggregate bitfields. */
4574 typedef struct {
4575 unsigned int bit_offset; /* current position in ... */
4576 int byte; /* ... the outer byte buffer. */
4577 } oc_outer_state;
4579 static unsigned HOST_WIDE_INT
4580 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int,
4581 oc_outer_state *);
4583 /* Output assembler code for constant EXP, with no label.
4584 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4585 Assumes output_addressed_constants has been done on EXP already.
4587 Generate at least SIZE bytes of assembler data, padding at the end
4588 with zeros if necessary. SIZE must always be specified. The returned
4589 value is the actual number of bytes of assembler data generated, which
4590 may be bigger than SIZE if the object contains a variable length field.
4592 SIZE is important for structure constructors,
4593 since trailing members may have been omitted from the constructor.
4594 It is also important for initialization of arrays from string constants
4595 since the full length of the string constant might not be wanted.
4596 It is also needed for initialization of unions, where the initializer's
4597 type is just one member, and that may not be as long as the union.
4599 There a case in which we would fail to output exactly SIZE bytes:
4600 for a structure constructor that wants to produce more than SIZE bytes.
4601 But such constructors will never be generated for any possible input.
4603 ALIGN is the alignment of the data in bits. */
4605 static unsigned HOST_WIDE_INT
4606 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align)
4608 enum tree_code code;
4609 unsigned HOST_WIDE_INT thissize;
4611 if (size == 0 || flag_syntax_only)
4612 return size;
4614 /* See if we're trying to initialize a pointer in a non-default mode
4615 to the address of some declaration somewhere. If the target says
4616 the mode is valid for pointers, assume the target has a way of
4617 resolving it. */
4618 if (TREE_CODE (exp) == NOP_EXPR
4619 && POINTER_TYPE_P (TREE_TYPE (exp))
4620 && targetm.addr_space.valid_pointer_mode
4621 (TYPE_MODE (TREE_TYPE (exp)),
4622 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4624 tree saved_type = TREE_TYPE (exp);
4626 /* Peel off any intermediate conversions-to-pointer for valid
4627 pointer modes. */
4628 while (TREE_CODE (exp) == NOP_EXPR
4629 && POINTER_TYPE_P (TREE_TYPE (exp))
4630 && targetm.addr_space.valid_pointer_mode
4631 (TYPE_MODE (TREE_TYPE (exp)),
4632 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4633 exp = TREE_OPERAND (exp, 0);
4635 /* If what we're left with is the address of something, we can
4636 convert the address to the final type and output it that
4637 way. */
4638 if (TREE_CODE (exp) == ADDR_EXPR)
4639 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4640 /* Likewise for constant ints. */
4641 else if (TREE_CODE (exp) == INTEGER_CST)
4642 exp = build_int_cst_wide (saved_type, TREE_INT_CST_LOW (exp),
4643 TREE_INT_CST_HIGH (exp));
4647 /* Eliminate any conversions since we'll be outputting the underlying
4648 constant. */
4649 while (CONVERT_EXPR_P (exp)
4650 || TREE_CODE (exp) == NON_LVALUE_EXPR
4651 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4653 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4654 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4656 /* Make sure eliminating the conversion is really a no-op, except with
4657 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4658 union types to allow for Ada unchecked unions. */
4659 if (type_size > op_size
4660 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4661 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4662 /* Keep the conversion. */
4663 break;
4664 else
4665 exp = TREE_OPERAND (exp, 0);
4668 code = TREE_CODE (TREE_TYPE (exp));
4669 thissize = int_size_in_bytes (TREE_TYPE (exp));
4671 /* Allow a constructor with no elements for any data type.
4672 This means to fill the space with zeros. */
4673 if (TREE_CODE (exp) == CONSTRUCTOR
4674 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4676 assemble_zeros (size);
4677 return size;
4680 if (TREE_CODE (exp) == FDESC_EXPR)
4682 #ifdef ASM_OUTPUT_FDESC
4683 HOST_WIDE_INT part = tree_to_shwi (TREE_OPERAND (exp, 1));
4684 tree decl = TREE_OPERAND (exp, 0);
4685 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4686 #else
4687 gcc_unreachable ();
4688 #endif
4689 return size;
4692 /* Now output the underlying data. If we've handling the padding, return.
4693 Otherwise, break and ensure SIZE is the size written. */
4694 switch (code)
4696 case BOOLEAN_TYPE:
4697 case INTEGER_TYPE:
4698 case ENUMERAL_TYPE:
4699 case POINTER_TYPE:
4700 case REFERENCE_TYPE:
4701 case OFFSET_TYPE:
4702 case FIXED_POINT_TYPE:
4703 case NULLPTR_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 return output_constructor (exp, size, align, NULL);
4729 case STRING_CST:
4730 thissize
4731 = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4732 assemble_string (TREE_STRING_POINTER (exp), thissize);
4733 break;
4734 case VECTOR_CST:
4736 enum machine_mode inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4737 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4738 int elt_size = GET_MODE_SIZE (inner);
4739 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align);
4740 thissize = elt_size;
4741 for (unsigned int i = 1; i < VECTOR_CST_NELTS (exp); i++)
4743 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign);
4744 thissize += elt_size;
4746 break;
4748 default:
4749 gcc_unreachable ();
4751 break;
4753 case RECORD_TYPE:
4754 case UNION_TYPE:
4755 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4756 return output_constructor (exp, size, align, NULL);
4758 case ERROR_MARK:
4759 return 0;
4761 default:
4762 gcc_unreachable ();
4765 if (size > thissize)
4766 assemble_zeros (size - thissize);
4768 return size;
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_to_shwi (TREE_OPERAND (local->index, 0));
4852 HOST_WIDE_INT hi_index
4853 = tree_to_shwi (TREE_OPERAND (local->index, 1));
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 fieldsize = 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_to_uhwi (TYPE_SIZE_UNIT (TREE_TYPE (local->val)))
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 assemble_zeros (fieldpos - local->total_bytes);
4917 local->total_bytes = fieldpos;
4920 /* Find the alignment of this element. */
4921 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
4923 /* Determine size this element should occupy. */
4924 if (local->field)
4926 fieldsize = 0;
4928 /* If this is an array with an unspecified upper bound,
4929 the initializer determines the size. */
4930 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
4931 but we cannot do this until the deprecated support for
4932 initializing zero-length array members is removed. */
4933 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
4934 && TYPE_DOMAIN (TREE_TYPE (local->field))
4935 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field))))
4937 fieldsize = array_size_for_constructor (local->val);
4938 /* Given a non-empty initialization, this field had
4939 better be last. */
4940 gcc_assert (!fieldsize || !DECL_CHAIN (local->field));
4942 else
4943 fieldsize = tree_to_uhwi (DECL_SIZE_UNIT (local->field));
4945 else
4946 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
4948 /* Output the element's initial value. */
4949 if (local->val == NULL_TREE)
4950 assemble_zeros (fieldsize);
4951 else
4952 fieldsize = output_constant (local->val, fieldsize, align2);
4954 /* Count its size. */
4955 local->total_bytes += fieldsize;
4958 /* Helper for output_constructor. From the LOCAL state, output an element
4959 that is a true bitfield or part of an outer one. BIT_OFFSET is the offset
4960 from the start of a possibly ongoing outer byte buffer. */
4962 static void
4963 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
4965 /* Bit size of this element. */
4966 HOST_WIDE_INT ebitsize
4967 = (local->field
4968 ? tree_to_uhwi (DECL_SIZE (local->field))
4969 : tree_to_uhwi (TYPE_SIZE (TREE_TYPE (local->type))));
4971 /* Relative index of this element if this is an array component. */
4972 HOST_WIDE_INT relative_index
4973 = (!local->field
4974 ? (local->index
4975 ? (tree_to_shwi (local->index)
4976 - tree_to_shwi (local->min_index))
4977 : local->last_relative_index + 1)
4978 : 0);
4980 /* Bit position of this element from the start of the containing
4981 constructor. */
4982 HOST_WIDE_INT constructor_relative_ebitpos
4983 = (local->field
4984 ? int_bit_position (local->field)
4985 : ebitsize * relative_index);
4987 /* Bit position of this element from the start of a possibly ongoing
4988 outer byte buffer. */
4989 HOST_WIDE_INT byte_relative_ebitpos
4990 = bit_offset + constructor_relative_ebitpos;
4992 /* From the start of a possibly ongoing outer byte buffer, offsets to
4993 the first bit of this element and to the first bit past the end of
4994 this element. */
4995 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
4996 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
4998 local->last_relative_index = relative_index;
5000 if (local->val == NULL_TREE)
5001 local->val = integer_zero_node;
5003 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
5004 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
5005 local->val = TREE_OPERAND (local->val, 0);
5007 if (TREE_CODE (local->val) != INTEGER_CST
5008 && TREE_CODE (local->val) != CONSTRUCTOR)
5010 error ("invalid initial value for member %qE", DECL_NAME (local->field));
5011 return;
5014 /* If this field does not start in this (or next) byte, skip some bytes. */
5015 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5017 /* Output remnant of any bit field in previous bytes. */
5018 if (local->byte_buffer_in_use)
5020 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5021 local->total_bytes++;
5022 local->byte_buffer_in_use = false;
5025 /* If still not at proper byte, advance to there. */
5026 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5028 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
5029 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
5030 local->total_bytes = next_offset / BITS_PER_UNIT;
5034 /* Set up the buffer if necessary. */
5035 if (!local->byte_buffer_in_use)
5037 local->byte = 0;
5038 if (ebitsize > 0)
5039 local->byte_buffer_in_use = true;
5042 /* If this is nested constructor, recurse passing the bit offset and the
5043 pending data, then retrieve the new pending data afterwards. */
5044 if (TREE_CODE (local->val) == CONSTRUCTOR)
5046 oc_outer_state temp_state;
5047 temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5048 temp_state.byte = local->byte;
5049 local->total_bytes
5050 += output_constructor (local->val, 0, 0, &temp_state);
5051 local->byte = temp_state.byte;
5052 return;
5055 /* Otherwise, we must split the element into pieces that fall within
5056 separate bytes, and combine each byte with previous or following
5057 bit-fields. */
5058 while (next_offset < end_offset)
5060 int this_time;
5061 int shift;
5062 HOST_WIDE_INT value;
5063 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5064 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5066 /* Advance from byte to byte within this element when necessary. */
5067 while (next_byte != local->total_bytes)
5069 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5070 local->total_bytes++;
5071 local->byte = 0;
5074 /* Number of bits we can process at once (all part of the same byte). */
5075 this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5076 if (BYTES_BIG_ENDIAN)
5078 /* On big-endian machine, take the most significant bits
5079 first (of the bits that are significant)
5080 and put them into bytes from the most significant end. */
5081 shift = end_offset - next_offset - this_time;
5083 /* Don't try to take a bunch of bits that cross
5084 the word boundary in the INTEGER_CST. We can
5085 only select bits from the LOW or HIGH part
5086 not from both. */
5087 if (shift < HOST_BITS_PER_WIDE_INT
5088 && shift + this_time > HOST_BITS_PER_WIDE_INT)
5090 this_time = shift + this_time - HOST_BITS_PER_WIDE_INT;
5091 shift = HOST_BITS_PER_WIDE_INT;
5094 /* Now get the bits from the appropriate constant word. */
5095 if (shift < HOST_BITS_PER_WIDE_INT)
5096 value = TREE_INT_CST_LOW (local->val);
5097 else
5099 gcc_assert (shift < HOST_BITS_PER_DOUBLE_INT);
5100 value = TREE_INT_CST_HIGH (local->val);
5101 shift -= HOST_BITS_PER_WIDE_INT;
5104 /* Get the result. This works only when:
5105 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5106 local->byte |= (((value >> shift)
5107 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5108 << (BITS_PER_UNIT - this_time - next_bit));
5110 else
5112 /* On little-endian machines,
5113 take first the least significant bits of the value
5114 and pack them starting at the least significant
5115 bits of the bytes. */
5116 shift = next_offset - byte_relative_ebitpos;
5118 /* Don't try to take a bunch of bits that cross
5119 the word boundary in the INTEGER_CST. We can
5120 only select bits from the LOW or HIGH part
5121 not from both. */
5122 if (shift < HOST_BITS_PER_WIDE_INT
5123 && shift + this_time > HOST_BITS_PER_WIDE_INT)
5124 this_time = (HOST_BITS_PER_WIDE_INT - shift);
5126 /* Now get the bits from the appropriate constant word. */
5127 if (shift < HOST_BITS_PER_WIDE_INT)
5128 value = TREE_INT_CST_LOW (local->val);
5129 else
5131 gcc_assert (shift < HOST_BITS_PER_DOUBLE_INT);
5132 value = TREE_INT_CST_HIGH (local->val);
5133 shift -= HOST_BITS_PER_WIDE_INT;
5136 /* Get the result. This works only when:
5137 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5138 local->byte |= (((value >> shift)
5139 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5140 << next_bit);
5143 next_offset += this_time;
5144 local->byte_buffer_in_use = true;
5148 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5149 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5150 caller output state of relevance in recursive invocations. */
5152 static unsigned HOST_WIDE_INT
5153 output_constructor (tree exp, unsigned HOST_WIDE_INT size,
5154 unsigned int align, oc_outer_state *outer)
5156 unsigned HOST_WIDE_INT cnt;
5157 constructor_elt *ce;
5159 oc_local_state local;
5161 /* Setup our local state to communicate with helpers. */
5162 local.exp = exp;
5163 local.type = TREE_TYPE (exp);
5164 local.size = size;
5165 local.align = align;
5166 if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5167 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5168 else
5169 local.min_index = NULL_TREE;
5171 local.total_bytes = 0;
5172 local.byte_buffer_in_use = outer != NULL;
5173 local.byte = outer ? outer->byte : 0;
5174 local.last_relative_index = -1;
5176 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5178 /* As CE goes through the elements of the constant, FIELD goes through the
5179 structure fields if the constant is a structure. If the constant is a
5180 union, we override this by getting the field from the TREE_LIST element.
5181 But the constant could also be an array. Then FIELD is zero.
5183 There is always a maximum of one element in the chain LINK for unions
5184 (even if the initializer in a source program incorrectly contains
5185 more one). */
5187 if (TREE_CODE (local.type) == RECORD_TYPE)
5188 local.field = TYPE_FIELDS (local.type);
5189 else
5190 local.field = NULL_TREE;
5192 for (cnt = 0;
5193 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5194 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5196 local.val = ce->value;
5197 local.index = NULL_TREE;
5199 /* The element in a union constructor specifies the proper field
5200 or index. */
5201 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5202 local.field = ce->index;
5204 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5205 local.index = ce->index;
5207 if (local.field && flag_verbose_asm)
5208 fprintf (asm_out_file, "%s %s:\n",
5209 ASM_COMMENT_START,
5210 DECL_NAME (local.field)
5211 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5212 : "<anonymous>");
5214 /* Eliminate the marker that makes a cast not be an lvalue. */
5215 if (local.val != NULL_TREE)
5216 STRIP_NOPS (local.val);
5218 /* Output the current element, using the appropriate helper ... */
5220 /* For an array slice not part of an outer bitfield. */
5221 if (!outer
5222 && local.index != NULL_TREE
5223 && TREE_CODE (local.index) == RANGE_EXPR)
5224 output_constructor_array_range (&local);
5226 /* For a field that is neither a true bitfield nor part of an outer one,
5227 known to be at least byte aligned and multiple-of-bytes long. */
5228 else if (!outer
5229 && (local.field == NULL_TREE
5230 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5231 output_constructor_regular_field (&local);
5233 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5234 supported for scalar fields, so we may need to convert first. */
5235 else
5237 if (TREE_CODE (local.val) == REAL_CST)
5238 local.val
5239 = fold_unary (VIEW_CONVERT_EXPR,
5240 build_nonstandard_integer_type
5241 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5242 local.val);
5243 output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5247 /* If we are not at toplevel, save the pending data for our caller.
5248 Otherwise output the pending data and padding zeros as needed. */
5249 if (outer)
5250 outer->byte = local.byte;
5251 else
5253 if (local.byte_buffer_in_use)
5255 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5256 local.total_bytes++;
5259 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5261 assemble_zeros (local.size - local.total_bytes);
5262 local.total_bytes = local.size;
5266 return local.total_bytes;
5269 /* Mark DECL as weak. */
5271 static void
5272 mark_weak (tree decl)
5274 DECL_WEAK (decl) = 1;
5276 if (DECL_RTL_SET_P (decl)
5277 && MEM_P (DECL_RTL (decl))
5278 && XEXP (DECL_RTL (decl), 0)
5279 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5280 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5283 /* Merge weak status between NEWDECL and OLDDECL. */
5285 void
5286 merge_weak (tree newdecl, tree olddecl)
5288 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5290 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5292 tree *pwd;
5293 /* We put the NEWDECL on the weak_decls list at some point
5294 and OLDDECL as well. Keep just OLDDECL on the list. */
5295 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5296 if (TREE_VALUE (*pwd) == newdecl)
5298 *pwd = TREE_CHAIN (*pwd);
5299 break;
5302 return;
5305 if (DECL_WEAK (newdecl))
5307 tree wd;
5309 /* NEWDECL is weak, but OLDDECL is not. */
5311 /* If we already output the OLDDECL, we're in trouble; we can't
5312 go back and make it weak. This should never happen in
5313 unit-at-a-time compilation. */
5314 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5316 /* If we've already generated rtl referencing OLDDECL, we may
5317 have done so in a way that will not function properly with
5318 a weak symbol. Again in unit-at-a-time this should be
5319 impossible. */
5320 gcc_assert (!TREE_USED (olddecl)
5321 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5323 if (TARGET_SUPPORTS_WEAK)
5325 /* We put the NEWDECL on the weak_decls list at some point.
5326 Replace it with the OLDDECL. */
5327 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5328 if (TREE_VALUE (wd) == newdecl)
5330 TREE_VALUE (wd) = olddecl;
5331 break;
5333 /* We may not find the entry on the list. If NEWDECL is a
5334 weak alias, then we will have already called
5335 globalize_decl to remove the entry; in that case, we do
5336 not need to do anything. */
5339 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5340 mark_weak (olddecl);
5342 else
5343 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5344 weak. Just update NEWDECL to indicate that it's weak too. */
5345 mark_weak (newdecl);
5348 /* Declare DECL to be a weak symbol. */
5350 void
5351 declare_weak (tree decl)
5353 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5354 if (! TREE_PUBLIC (decl))
5355 error ("weak declaration of %q+D must be public", decl);
5356 else if (!TARGET_SUPPORTS_WEAK)
5357 warning (0, "weak declaration of %q+D not supported", decl);
5359 mark_weak (decl);
5360 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5361 DECL_ATTRIBUTES (decl)
5362 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5365 static void
5366 weak_finish_1 (tree decl)
5368 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5369 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5370 #endif
5372 if (! TREE_USED (decl))
5373 return;
5375 #ifdef ASM_WEAKEN_DECL
5376 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5377 #else
5378 #ifdef ASM_WEAKEN_LABEL
5379 ASM_WEAKEN_LABEL (asm_out_file, name);
5380 #else
5381 #ifdef ASM_OUTPUT_WEAK_ALIAS
5383 static bool warn_once = 0;
5384 if (! warn_once)
5386 warning (0, "only weak aliases are supported in this configuration");
5387 warn_once = 1;
5389 return;
5391 #endif
5392 #endif
5393 #endif
5396 /* Fiven an assembly name, find the decl it is associated with. */
5397 static tree
5398 find_decl (tree target)
5400 symtab_node *node = symtab_node_for_asm (target);
5401 if (node)
5402 return node->decl;
5403 return NULL_TREE;
5406 /* This TREE_LIST contains weakref targets. */
5408 static GTY(()) tree weakref_targets;
5410 /* Emit any pending weak declarations. */
5412 void
5413 weak_finish (void)
5415 tree t;
5417 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5419 tree alias_decl = TREE_PURPOSE (t);
5420 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5422 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5423 /* Remove alias_decl from the weak list, but leave entries for
5424 the target alone. */
5425 target = NULL_TREE;
5426 #ifndef ASM_OUTPUT_WEAKREF
5427 else if (! TREE_SYMBOL_REFERENCED (target))
5429 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5430 defined, otherwise we and weak_finish_1 would use
5431 different macros. */
5432 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5433 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5434 # else
5435 tree decl = find_decl (target);
5437 if (! decl)
5439 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5440 TREE_CODE (alias_decl), target,
5441 TREE_TYPE (alias_decl));
5443 DECL_EXTERNAL (decl) = 1;
5444 TREE_PUBLIC (decl) = 1;
5445 DECL_ARTIFICIAL (decl) = 1;
5446 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5447 TREE_USED (decl) = 1;
5450 weak_finish_1 (decl);
5451 # endif
5453 #endif
5456 tree *p;
5457 tree t2;
5459 /* Remove the alias and the target from the pending weak list
5460 so that we do not emit any .weak directives for the former,
5461 nor multiple .weak directives for the latter. */
5462 for (p = &weak_decls; (t2 = *p) ; )
5464 if (TREE_VALUE (t2) == alias_decl
5465 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5466 *p = TREE_CHAIN (t2);
5467 else
5468 p = &TREE_CHAIN (t2);
5471 /* Remove other weakrefs to the same target, to speed things up. */
5472 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5474 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5475 *p = TREE_CHAIN (t2);
5476 else
5477 p = &TREE_CHAIN (t2);
5482 for (t = weak_decls; t; t = TREE_CHAIN (t))
5484 tree decl = TREE_VALUE (t);
5486 weak_finish_1 (decl);
5490 /* Emit the assembly bits to indicate that DECL is globally visible. */
5492 static void
5493 globalize_decl (tree decl)
5496 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5497 if (DECL_WEAK (decl))
5499 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5500 tree *p, t;
5502 #ifdef ASM_WEAKEN_DECL
5503 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5504 #else
5505 ASM_WEAKEN_LABEL (asm_out_file, name);
5506 #endif
5508 /* Remove this function from the pending weak list so that
5509 we do not emit multiple .weak directives for it. */
5510 for (p = &weak_decls; (t = *p) ; )
5512 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5513 *p = TREE_CHAIN (t);
5514 else
5515 p = &TREE_CHAIN (t);
5518 /* Remove weakrefs to the same target from the pending weakref
5519 list, for the same reason. */
5520 for (p = &weakref_targets; (t = *p) ; )
5522 if (DECL_ASSEMBLER_NAME (decl)
5523 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5524 *p = TREE_CHAIN (t);
5525 else
5526 p = &TREE_CHAIN (t);
5529 return;
5531 #endif
5533 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5536 vec<alias_pair, va_gc> *alias_pairs;
5538 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5539 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5540 tree node is DECL to have the value of the tree node TARGET. */
5542 void
5543 do_assemble_alias (tree decl, tree target)
5545 /* Emulated TLS had better not get this var. */
5546 gcc_assert (!(!targetm.have_tls
5547 && TREE_CODE (decl) == VAR_DECL
5548 && DECL_THREAD_LOCAL_P (decl)));
5550 if (TREE_ASM_WRITTEN (decl))
5551 return;
5553 /* We must force creation of DECL_RTL for debug info generation, even though
5554 we don't use it here. */
5555 make_decl_rtl (decl);
5557 TREE_ASM_WRITTEN (decl) = 1;
5558 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5560 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5562 ultimate_transparent_alias_target (&target);
5564 if (!TREE_SYMBOL_REFERENCED (target))
5565 weakref_targets = tree_cons (decl, target, weakref_targets);
5567 #ifdef ASM_OUTPUT_WEAKREF
5568 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5569 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5570 IDENTIFIER_POINTER (target));
5571 #else
5572 if (!TARGET_SUPPORTS_WEAK)
5574 error_at (DECL_SOURCE_LOCATION (decl),
5575 "weakref is not supported in this configuration");
5576 return;
5578 #endif
5579 return;
5582 #ifdef ASM_OUTPUT_DEF
5583 /* Make name accessible from other files, if appropriate. */
5585 if (TREE_PUBLIC (decl))
5587 globalize_decl (decl);
5588 maybe_assemble_visibility (decl);
5590 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5592 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5593 if (targetm.has_ifunc_p ())
5594 ASM_OUTPUT_TYPE_DIRECTIVE
5595 (asm_out_file, IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5596 IFUNC_ASM_TYPE);
5597 else
5598 #endif
5599 error_at (DECL_SOURCE_LOCATION (decl),
5600 "ifunc is not supported on this target");
5603 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5604 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5605 # else
5606 ASM_OUTPUT_DEF (asm_out_file,
5607 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5608 IDENTIFIER_POINTER (target));
5609 # endif
5610 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5612 const char *name;
5613 tree *p, t;
5615 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5616 # ifdef ASM_WEAKEN_DECL
5617 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5618 # else
5619 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5620 # endif
5621 /* Remove this function from the pending weak list so that
5622 we do not emit multiple .weak directives for it. */
5623 for (p = &weak_decls; (t = *p) ; )
5624 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5625 *p = TREE_CHAIN (t);
5626 else
5627 p = &TREE_CHAIN (t);
5629 /* Remove weakrefs to the same target from the pending weakref
5630 list, for the same reason. */
5631 for (p = &weakref_targets; (t = *p) ; )
5633 if (DECL_ASSEMBLER_NAME (decl)
5634 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5635 *p = TREE_CHAIN (t);
5636 else
5637 p = &TREE_CHAIN (t);
5640 #endif
5643 /* Emit an assembler directive to make the symbol for DECL an alias to
5644 the symbol for TARGET. */
5646 void
5647 assemble_alias (tree decl, tree target)
5649 tree target_decl;
5651 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5653 tree alias = DECL_ASSEMBLER_NAME (decl);
5655 ultimate_transparent_alias_target (&target);
5657 if (alias == target)
5658 error ("weakref %q+D ultimately targets itself", decl);
5659 if (TREE_PUBLIC (decl))
5660 error ("weakref %q+D must have static linkage", decl);
5662 else
5664 #if !defined (ASM_OUTPUT_DEF)
5665 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5666 error_at (DECL_SOURCE_LOCATION (decl),
5667 "alias definitions not supported in this configuration");
5668 TREE_ASM_WRITTEN (decl) = 1;
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 TREE_ASM_WRITTEN (decl) = 1;
5680 return;
5682 # endif
5683 #endif
5685 TREE_USED (decl) = 1;
5687 /* Allow aliases to aliases. */
5688 if (TREE_CODE (decl) == FUNCTION_DECL)
5689 cgraph_get_create_node (decl)->alias = true;
5690 else
5691 varpool_node_for_decl (decl)->alias = true;
5693 /* If the target has already been emitted, we don't have to queue the
5694 alias. This saves a tad of memory. */
5695 if (cgraph_global_info_ready)
5696 target_decl = find_decl (target);
5697 else
5698 target_decl= NULL;
5699 if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5700 || cgraph_state >= CGRAPH_STATE_EXPANSION)
5701 do_assemble_alias (decl, target);
5702 else
5704 alias_pair p = {decl, target};
5705 vec_safe_push (alias_pairs, p);
5709 /* Record and output a table of translations from original function
5710 to its transaction aware clone. Note that tm_pure functions are
5711 considered to be their own clone. */
5713 static GTY((if_marked ("tree_map_marked_p"), param_is (struct tree_map)))
5714 htab_t tm_clone_hash;
5716 void
5717 record_tm_clone_pair (tree o, tree n)
5719 struct tree_map **slot, *h;
5721 if (tm_clone_hash == NULL)
5722 tm_clone_hash = htab_create_ggc (32, tree_map_hash, tree_map_eq, 0);
5724 h = ggc_alloc_tree_map ();
5725 h->hash = htab_hash_pointer (o);
5726 h->base.from = o;
5727 h->to = n;
5729 slot = (struct tree_map **)
5730 htab_find_slot_with_hash (tm_clone_hash, h, h->hash, INSERT);
5731 *slot = h;
5734 tree
5735 get_tm_clone_pair (tree o)
5737 if (tm_clone_hash)
5739 struct tree_map *h, in;
5741 in.base.from = o;
5742 in.hash = htab_hash_pointer (o);
5743 h = (struct tree_map *) htab_find_with_hash (tm_clone_hash,
5744 &in, in.hash);
5745 if (h)
5746 return h->to;
5748 return NULL_TREE;
5751 typedef struct tm_alias_pair
5753 unsigned int uid;
5754 tree from;
5755 tree to;
5756 } tm_alias_pair;
5759 /* Helper function for finish_tm_clone_pairs. Dump a hash table entry
5760 into a VEC in INFO. */
5762 static int
5763 dump_tm_clone_to_vec (void **slot, void *info)
5765 struct tree_map *map = (struct tree_map *) *slot;
5766 vec<tm_alias_pair> *tm_alias_pairs = (vec<tm_alias_pair> *) info;
5767 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
5768 tm_alias_pairs->safe_push (p);
5769 return 1;
5772 /* Dump the actual pairs to the .tm_clone_table section. */
5774 static void
5775 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
5777 unsigned i;
5778 tm_alias_pair *p;
5779 bool switched = false;
5781 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
5783 tree src = p->from;
5784 tree dst = p->to;
5785 struct cgraph_node *src_n = cgraph_get_node (src);
5786 struct cgraph_node *dst_n = cgraph_get_node (dst);
5788 /* The function ipa_tm_create_version() marks the clone as needed if
5789 the original function was needed. But we also mark the clone as
5790 needed if we ever called the clone indirectly through
5791 TM_GETTMCLONE. If neither of these are true, we didn't generate
5792 a clone, and we didn't call it indirectly... no sense keeping it
5793 in the clone table. */
5794 if (!dst_n || !dst_n->definition)
5795 continue;
5797 /* This covers the case where we have optimized the original
5798 function away, and only access the transactional clone. */
5799 if (!src_n || !src_n->definition)
5800 continue;
5802 if (!switched)
5804 switch_to_section (targetm.asm_out.tm_clone_table_section ());
5805 assemble_align (POINTER_SIZE);
5806 switched = true;
5809 assemble_integer (XEXP (DECL_RTL (src), 0),
5810 POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
5811 assemble_integer (XEXP (DECL_RTL (dst), 0),
5812 POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
5816 /* Provide a default for the tm_clone_table section. */
5818 section *
5819 default_clone_table_section (void)
5821 return get_named_section (NULL, ".tm_clone_table", 3);
5824 /* Helper comparison function for qsorting by the DECL_UID stored in
5825 alias_pair->emitted_diags. */
5827 static int
5828 tm_alias_pair_cmp (const void *x, const void *y)
5830 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
5831 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
5832 if (p1->uid < p2->uid)
5833 return -1;
5834 if (p1->uid > p2->uid)
5835 return 1;
5836 return 0;
5839 void
5840 finish_tm_clone_pairs (void)
5842 vec<tm_alias_pair> tm_alias_pairs = vNULL;
5844 if (tm_clone_hash == NULL)
5845 return;
5847 /* We need a determenistic order for the .tm_clone_table, otherwise
5848 we will get bootstrap comparison failures, so dump the hash table
5849 to a vector, sort it, and dump the vector. */
5851 /* Dump the hashtable to a vector. */
5852 htab_traverse_noresize (tm_clone_hash, dump_tm_clone_to_vec,
5853 (void *) &tm_alias_pairs);
5854 /* Sort it. */
5855 tm_alias_pairs.qsort (tm_alias_pair_cmp);
5857 /* Dump it. */
5858 dump_tm_clone_pairs (tm_alias_pairs);
5860 htab_delete (tm_clone_hash);
5861 tm_clone_hash = NULL;
5862 tm_alias_pairs.release ();
5866 /* Emit an assembler directive to set symbol for DECL visibility to
5867 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
5869 void
5870 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
5871 int vis ATTRIBUTE_UNUSED)
5873 #ifdef HAVE_GAS_HIDDEN
5874 static const char * const visibility_types[] = {
5875 NULL, "protected", "hidden", "internal"
5878 const char *name, *type;
5880 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5881 type = visibility_types[vis];
5883 fprintf (asm_out_file, "\t.%s\t", type);
5884 assemble_name (asm_out_file, name);
5885 fprintf (asm_out_file, "\n");
5886 #else
5887 if (!DECL_ARTIFICIAL (decl))
5888 warning (OPT_Wattributes, "visibility attribute not supported "
5889 "in this configuration; ignored");
5890 #endif
5893 /* A helper function to call assemble_visibility when needed for a decl. */
5896 maybe_assemble_visibility (tree decl)
5898 enum symbol_visibility vis = DECL_VISIBILITY (decl);
5900 if (vis != VISIBILITY_DEFAULT)
5902 targetm.asm_out.assemble_visibility (decl, vis);
5903 return 1;
5905 else
5906 return 0;
5909 /* Returns 1 if the target configuration supports defining public symbols
5910 so that one of them will be chosen at link time instead of generating a
5911 multiply-defined symbol error, whether through the use of weak symbols or
5912 a target-specific mechanism for having duplicates discarded. */
5915 supports_one_only (void)
5917 if (SUPPORTS_ONE_ONLY)
5918 return 1;
5919 return TARGET_SUPPORTS_WEAK;
5922 /* Set up DECL as a public symbol that can be defined in multiple
5923 translation units without generating a linker error. */
5925 void
5926 make_decl_one_only (tree decl, tree comdat_group)
5928 gcc_assert (TREE_CODE (decl) == VAR_DECL
5929 || TREE_CODE (decl) == FUNCTION_DECL);
5931 TREE_PUBLIC (decl) = 1;
5933 if (SUPPORTS_ONE_ONLY)
5935 #ifdef MAKE_DECL_ONE_ONLY
5936 MAKE_DECL_ONE_ONLY (decl);
5937 #endif
5938 DECL_COMDAT_GROUP (decl) = comdat_group;
5940 else if (TREE_CODE (decl) == VAR_DECL
5941 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node))
5942 DECL_COMMON (decl) = 1;
5943 else
5945 gcc_assert (TARGET_SUPPORTS_WEAK);
5946 DECL_WEAK (decl) = 1;
5950 void
5951 init_varasm_once (void)
5953 section_htab = htab_create_ggc (31, section_entry_hash,
5954 section_entry_eq, NULL);
5955 object_block_htab = htab_create_ggc (31, object_block_entry_hash,
5956 object_block_entry_eq, NULL);
5957 const_desc_htab = htab_create_ggc (1009, const_desc_hash,
5958 const_desc_eq, NULL);
5960 const_alias_set = new_alias_set ();
5961 shared_constant_pool = create_constant_pool ();
5963 #ifdef TEXT_SECTION_ASM_OP
5964 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
5965 TEXT_SECTION_ASM_OP);
5966 #endif
5968 #ifdef DATA_SECTION_ASM_OP
5969 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5970 DATA_SECTION_ASM_OP);
5971 #endif
5973 #ifdef SDATA_SECTION_ASM_OP
5974 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5975 SDATA_SECTION_ASM_OP);
5976 #endif
5978 #ifdef READONLY_DATA_SECTION_ASM_OP
5979 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
5980 READONLY_DATA_SECTION_ASM_OP);
5981 #endif
5983 #ifdef CTORS_SECTION_ASM_OP
5984 ctors_section = get_unnamed_section (0, output_section_asm_op,
5985 CTORS_SECTION_ASM_OP);
5986 #endif
5988 #ifdef DTORS_SECTION_ASM_OP
5989 dtors_section = get_unnamed_section (0, output_section_asm_op,
5990 DTORS_SECTION_ASM_OP);
5991 #endif
5993 #ifdef BSS_SECTION_ASM_OP
5994 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5995 output_section_asm_op,
5996 BSS_SECTION_ASM_OP);
5997 #endif
5999 #ifdef SBSS_SECTION_ASM_OP
6000 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6001 output_section_asm_op,
6002 SBSS_SECTION_ASM_OP);
6003 #endif
6005 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6006 | SECTION_COMMON, emit_tls_common);
6007 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6008 | SECTION_COMMON, emit_local);
6009 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6010 | SECTION_COMMON, emit_common);
6012 #if defined ASM_OUTPUT_ALIGNED_BSS
6013 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
6014 emit_bss);
6015 #endif
6017 targetm.asm_out.init_sections ();
6019 if (readonly_data_section == NULL)
6020 readonly_data_section = text_section;
6022 #ifdef ASM_OUTPUT_EXTERNAL
6023 pending_assemble_externals_set = pointer_set_create ();
6024 #endif
6027 enum tls_model
6028 decl_default_tls_model (const_tree decl)
6030 enum tls_model kind;
6031 bool is_local;
6033 is_local = targetm.binds_local_p (decl);
6034 if (!flag_shlib)
6036 if (is_local)
6037 kind = TLS_MODEL_LOCAL_EXEC;
6038 else
6039 kind = TLS_MODEL_INITIAL_EXEC;
6042 /* Local dynamic is inefficient when we're not combining the
6043 parts of the address. */
6044 else if (optimize && is_local)
6045 kind = TLS_MODEL_LOCAL_DYNAMIC;
6046 else
6047 kind = TLS_MODEL_GLOBAL_DYNAMIC;
6048 if (kind < flag_tls_default)
6049 kind = flag_tls_default;
6051 return kind;
6054 /* Select a set of attributes for section NAME based on the properties
6055 of DECL and whether or not RELOC indicates that DECL's initializer
6056 might contain runtime relocations.
6058 We make the section read-only and executable for a function decl,
6059 read-only for a const data decl, and writable for a non-const data decl. */
6061 unsigned int
6062 default_section_type_flags (tree decl, const char *name, int reloc)
6064 unsigned int flags;
6066 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6067 flags = SECTION_CODE;
6068 else if (decl)
6070 enum section_category category
6071 = categorize_decl_for_section (decl, reloc);
6072 if (decl_readonly_section_1 (category))
6073 flags = 0;
6074 else if (category == SECCAT_DATA_REL_RO
6075 || category == SECCAT_DATA_REL_RO_LOCAL)
6076 flags = SECTION_WRITE | SECTION_RELRO;
6077 else
6078 flags = SECTION_WRITE;
6080 else
6082 flags = SECTION_WRITE;
6083 if (strcmp (name, ".data.rel.ro") == 0
6084 || strcmp (name, ".data.rel.ro.local") == 0)
6085 flags |= SECTION_RELRO;
6088 if (decl && DECL_P (decl) && DECL_ONE_ONLY (decl))
6089 flags |= SECTION_LINKONCE;
6091 if (strcmp (name, ".vtable_map_vars") == 0)
6092 flags |= SECTION_LINKONCE;
6094 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6095 flags |= SECTION_TLS | SECTION_WRITE;
6097 if (strcmp (name, ".bss") == 0
6098 || strncmp (name, ".bss.", 5) == 0
6099 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6100 || strcmp (name, ".sbss") == 0
6101 || strncmp (name, ".sbss.", 6) == 0
6102 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6103 flags |= SECTION_BSS;
6105 if (strcmp (name, ".tdata") == 0
6106 || strncmp (name, ".tdata.", 7) == 0
6107 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6108 flags |= SECTION_TLS;
6110 if (strcmp (name, ".tbss") == 0
6111 || strncmp (name, ".tbss.", 6) == 0
6112 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6113 flags |= SECTION_TLS | SECTION_BSS;
6115 /* These three sections have special ELF types. They are neither
6116 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
6117 want to print a section type (@progbits or @nobits). If someone
6118 is silly enough to emit code or TLS variables to one of these
6119 sections, then don't handle them specially. */
6120 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6121 && (strcmp (name, ".init_array") == 0
6122 || strcmp (name, ".fini_array") == 0
6123 || strcmp (name, ".preinit_array") == 0))
6124 flags |= SECTION_NOTYPE;
6126 return flags;
6129 /* Return true if the target supports some form of global BSS,
6130 either through bss_noswitch_section, or by selecting a BSS
6131 section in TARGET_ASM_SELECT_SECTION. */
6133 bool
6134 have_global_bss_p (void)
6136 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6139 /* Output assembly to switch to section NAME with attribute FLAGS.
6140 Four variants for common object file formats. */
6142 void
6143 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6144 unsigned int flags ATTRIBUTE_UNUSED,
6145 tree decl ATTRIBUTE_UNUSED)
6147 /* Some object formats don't support named sections at all. The
6148 front-end should already have flagged this as an error. */
6149 gcc_unreachable ();
6152 #ifndef TLS_SECTION_ASM_FLAG
6153 #define TLS_SECTION_ASM_FLAG 'T'
6154 #endif
6156 void
6157 default_elf_asm_named_section (const char *name, unsigned int flags,
6158 tree decl ATTRIBUTE_UNUSED)
6160 char flagchars[10], *f = flagchars;
6162 /* If we have already declared this section, we can use an
6163 abbreviated form to switch back to it -- unless this section is
6164 part of a COMDAT groups, in which case GAS requires the full
6165 declaration every time. */
6166 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6167 && (flags & SECTION_DECLARED))
6169 fprintf (asm_out_file, "\t.section\t%s\n", name);
6170 return;
6173 if (!(flags & SECTION_DEBUG))
6174 *f++ = 'a';
6175 if (flags & SECTION_EXCLUDE)
6176 *f++ = 'e';
6177 if (flags & SECTION_WRITE)
6178 *f++ = 'w';
6179 if (flags & SECTION_CODE)
6180 *f++ = 'x';
6181 if (flags & SECTION_SMALL)
6182 *f++ = 's';
6183 if (flags & SECTION_MERGE)
6184 *f++ = 'M';
6185 if (flags & SECTION_STRINGS)
6186 *f++ = 'S';
6187 if (flags & SECTION_TLS)
6188 *f++ = TLS_SECTION_ASM_FLAG;
6189 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6190 *f++ = 'G';
6191 *f = '\0';
6193 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6195 if (!(flags & SECTION_NOTYPE))
6197 const char *type;
6198 const char *format;
6200 if (flags & SECTION_BSS)
6201 type = "nobits";
6202 else
6203 type = "progbits";
6205 format = ",@%s";
6206 /* On platforms that use "@" as the assembly comment character,
6207 use "%" instead. */
6208 if (strcmp (ASM_COMMENT_START, "@") == 0)
6209 format = ",%%%s";
6210 fprintf (asm_out_file, format, type);
6212 if (flags & SECTION_ENTSIZE)
6213 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6214 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6216 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6217 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6218 else
6219 fprintf (asm_out_file, ",%s,comdat",
6220 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6224 putc ('\n', asm_out_file);
6227 void
6228 default_coff_asm_named_section (const char *name, unsigned int flags,
6229 tree decl ATTRIBUTE_UNUSED)
6231 char flagchars[8], *f = flagchars;
6233 if (flags & SECTION_WRITE)
6234 *f++ = 'w';
6235 if (flags & SECTION_CODE)
6236 *f++ = 'x';
6237 *f = '\0';
6239 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6242 void
6243 default_pe_asm_named_section (const char *name, unsigned int flags,
6244 tree decl)
6246 default_coff_asm_named_section (name, flags, decl);
6248 if (flags & SECTION_LINKONCE)
6250 /* Functions may have been compiled at various levels of
6251 optimization so we can't use `same_size' here.
6252 Instead, have the linker pick one. */
6253 fprintf (asm_out_file, "\t.linkonce %s\n",
6254 (flags & SECTION_CODE ? "discard" : "same_size"));
6258 /* The lame default section selector. */
6260 section *
6261 default_select_section (tree decl, int reloc,
6262 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6264 if (DECL_P (decl))
6266 if (decl_readonly_section (decl, reloc))
6267 return readonly_data_section;
6269 else if (TREE_CODE (decl) == CONSTRUCTOR)
6271 if (! ((flag_pic && reloc)
6272 || !TREE_READONLY (decl)
6273 || TREE_SIDE_EFFECTS (decl)
6274 || !TREE_CONSTANT (decl)))
6275 return readonly_data_section;
6277 else if (TREE_CODE (decl) == STRING_CST)
6278 return readonly_data_section;
6279 else if (! (flag_pic && reloc))
6280 return readonly_data_section;
6282 return data_section;
6285 enum section_category
6286 categorize_decl_for_section (const_tree decl, int reloc)
6288 enum section_category ret;
6290 if (TREE_CODE (decl) == FUNCTION_DECL)
6291 return SECCAT_TEXT;
6292 else if (TREE_CODE (decl) == STRING_CST)
6294 if ((flag_sanitize & SANITIZE_ADDRESS)
6295 && asan_protect_global (CONST_CAST_TREE (decl)))
6296 /* or !flag_merge_constants */
6297 return SECCAT_RODATA;
6298 else
6299 return SECCAT_RODATA_MERGE_STR;
6301 else if (TREE_CODE (decl) == VAR_DECL)
6303 if (bss_initializer_p (decl))
6304 ret = SECCAT_BSS;
6305 else if (! TREE_READONLY (decl)
6306 || TREE_SIDE_EFFECTS (decl)
6307 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
6309 /* Here the reloc_rw_mask is not testing whether the section should
6310 be read-only or not, but whether the dynamic link will have to
6311 do something. If so, we wish to segregate the data in order to
6312 minimize cache misses inside the dynamic linker. */
6313 if (reloc & targetm.asm_out.reloc_rw_mask ())
6314 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6315 else
6316 ret = SECCAT_DATA;
6318 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6319 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6320 else if (reloc || flag_merge_constants < 2
6321 || ((flag_sanitize & SANITIZE_ADDRESS)
6322 && asan_protect_global (CONST_CAST_TREE (decl))))
6323 /* C and C++ don't allow different variables to share the same
6324 location. -fmerge-all-constants allows even that (at the
6325 expense of not conforming). */
6326 ret = SECCAT_RODATA;
6327 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6328 ret = SECCAT_RODATA_MERGE_STR_INIT;
6329 else
6330 ret = SECCAT_RODATA_MERGE_CONST;
6332 else if (TREE_CODE (decl) == CONSTRUCTOR)
6334 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6335 || TREE_SIDE_EFFECTS (decl)
6336 || ! TREE_CONSTANT (decl))
6337 ret = SECCAT_DATA;
6338 else
6339 ret = SECCAT_RODATA;
6341 else
6342 ret = SECCAT_RODATA;
6344 /* There are no read-only thread-local sections. */
6345 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6347 /* Note that this would be *just* SECCAT_BSS, except that there's
6348 no concept of a read-only thread-local-data section. */
6349 if (ret == SECCAT_BSS
6350 || (flag_zero_initialized_in_bss
6351 && initializer_zerop (DECL_INITIAL (decl))))
6352 ret = SECCAT_TBSS;
6353 else
6354 ret = SECCAT_TDATA;
6357 /* If the target uses small data sections, select it. */
6358 else if (targetm.in_small_data_p (decl))
6360 if (ret == SECCAT_BSS)
6361 ret = SECCAT_SBSS;
6362 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6363 ret = SECCAT_SRODATA;
6364 else
6365 ret = SECCAT_SDATA;
6368 return ret;
6371 static bool
6372 decl_readonly_section_1 (enum section_category category)
6374 switch (category)
6376 case SECCAT_RODATA:
6377 case SECCAT_RODATA_MERGE_STR:
6378 case SECCAT_RODATA_MERGE_STR_INIT:
6379 case SECCAT_RODATA_MERGE_CONST:
6380 case SECCAT_SRODATA:
6381 return true;
6382 default:
6383 return false;
6387 bool
6388 decl_readonly_section (const_tree decl, int reloc)
6390 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6393 /* Select a section based on the above categorization. */
6395 section *
6396 default_elf_select_section (tree decl, int reloc,
6397 unsigned HOST_WIDE_INT align)
6399 const char *sname;
6400 switch (categorize_decl_for_section (decl, reloc))
6402 case SECCAT_TEXT:
6403 /* We're not supposed to be called on FUNCTION_DECLs. */
6404 gcc_unreachable ();
6405 case SECCAT_RODATA:
6406 return readonly_data_section;
6407 case SECCAT_RODATA_MERGE_STR:
6408 return mergeable_string_section (decl, align, 0);
6409 case SECCAT_RODATA_MERGE_STR_INIT:
6410 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6411 case SECCAT_RODATA_MERGE_CONST:
6412 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6413 case SECCAT_SRODATA:
6414 sname = ".sdata2";
6415 break;
6416 case SECCAT_DATA:
6417 return data_section;
6418 case SECCAT_DATA_REL:
6419 sname = ".data.rel";
6420 break;
6421 case SECCAT_DATA_REL_LOCAL:
6422 sname = ".data.rel.local";
6423 break;
6424 case SECCAT_DATA_REL_RO:
6425 sname = ".data.rel.ro";
6426 break;
6427 case SECCAT_DATA_REL_RO_LOCAL:
6428 sname = ".data.rel.ro.local";
6429 break;
6430 case SECCAT_SDATA:
6431 sname = ".sdata";
6432 break;
6433 case SECCAT_TDATA:
6434 sname = ".tdata";
6435 break;
6436 case SECCAT_BSS:
6437 if (bss_section)
6438 return bss_section;
6439 sname = ".bss";
6440 break;
6441 case SECCAT_SBSS:
6442 sname = ".sbss";
6443 break;
6444 case SECCAT_TBSS:
6445 sname = ".tbss";
6446 break;
6447 default:
6448 gcc_unreachable ();
6451 return get_named_section (decl, sname, reloc);
6454 /* Construct a unique section name based on the decl name and the
6455 categorization performed above. */
6457 void
6458 default_unique_section (tree decl, int reloc)
6460 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6461 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6462 const char *prefix, *name, *linkonce;
6463 char *string;
6465 switch (categorize_decl_for_section (decl, reloc))
6467 case SECCAT_TEXT:
6468 prefix = one_only ? ".t" : ".text";
6469 break;
6470 case SECCAT_RODATA:
6471 case SECCAT_RODATA_MERGE_STR:
6472 case SECCAT_RODATA_MERGE_STR_INIT:
6473 case SECCAT_RODATA_MERGE_CONST:
6474 prefix = one_only ? ".r" : ".rodata";
6475 break;
6476 case SECCAT_SRODATA:
6477 prefix = one_only ? ".s2" : ".sdata2";
6478 break;
6479 case SECCAT_DATA:
6480 prefix = one_only ? ".d" : ".data";
6481 break;
6482 case SECCAT_DATA_REL:
6483 prefix = one_only ? ".d.rel" : ".data.rel";
6484 break;
6485 case SECCAT_DATA_REL_LOCAL:
6486 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6487 break;
6488 case SECCAT_DATA_REL_RO:
6489 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6490 break;
6491 case SECCAT_DATA_REL_RO_LOCAL:
6492 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6493 break;
6494 case SECCAT_SDATA:
6495 prefix = one_only ? ".s" : ".sdata";
6496 break;
6497 case SECCAT_BSS:
6498 prefix = one_only ? ".b" : ".bss";
6499 break;
6500 case SECCAT_SBSS:
6501 prefix = one_only ? ".sb" : ".sbss";
6502 break;
6503 case SECCAT_TDATA:
6504 prefix = one_only ? ".td" : ".tdata";
6505 break;
6506 case SECCAT_TBSS:
6507 prefix = one_only ? ".tb" : ".tbss";
6508 break;
6509 default:
6510 gcc_unreachable ();
6513 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
6514 name = targetm.strip_name_encoding (name);
6516 /* If we're using one_only, then there needs to be a .gnu.linkonce
6517 prefix to the section name. */
6518 linkonce = one_only ? ".gnu.linkonce" : "";
6520 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6522 DECL_SECTION_NAME (decl) = build_string (strlen (string), string);
6525 /* Like compute_reloc_for_constant, except for an RTX. The return value
6526 is a mask for which bit 1 indicates a global relocation, and bit 0
6527 indicates a local relocation. */
6529 static int
6530 compute_reloc_for_rtx_1 (rtx *xp, void *data)
6532 int *preloc = (int *) data;
6533 rtx x = *xp;
6535 switch (GET_CODE (x))
6537 case SYMBOL_REF:
6538 *preloc |= SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6539 break;
6540 case LABEL_REF:
6541 *preloc |= 1;
6542 break;
6543 default:
6544 break;
6547 return 0;
6550 static int
6551 compute_reloc_for_rtx (rtx x)
6553 int reloc;
6555 switch (GET_CODE (x))
6557 case CONST:
6558 case SYMBOL_REF:
6559 case LABEL_REF:
6560 reloc = 0;
6561 for_each_rtx (&x, compute_reloc_for_rtx_1, &reloc);
6562 return reloc;
6564 default:
6565 return 0;
6569 section *
6570 default_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
6571 rtx x,
6572 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6574 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6575 return data_section;
6576 else
6577 return readonly_data_section;
6580 section *
6581 default_elf_select_rtx_section (enum machine_mode mode, rtx x,
6582 unsigned HOST_WIDE_INT align)
6584 int reloc = compute_reloc_for_rtx (x);
6586 /* ??? Handle small data here somehow. */
6588 if (reloc & targetm.asm_out.reloc_rw_mask ())
6590 if (reloc == 1)
6591 return get_named_section (NULL, ".data.rel.ro.local", 1);
6592 else
6593 return get_named_section (NULL, ".data.rel.ro", 3);
6596 return mergeable_constant_section (mode, align, 0);
6599 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6601 void
6602 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6604 rtx symbol;
6605 int flags;
6607 /* Careful not to prod global register variables. */
6608 if (!MEM_P (rtl))
6609 return;
6610 symbol = XEXP (rtl, 0);
6611 if (GET_CODE (symbol) != SYMBOL_REF)
6612 return;
6614 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6615 if (TREE_CODE (decl) == FUNCTION_DECL)
6616 flags |= SYMBOL_FLAG_FUNCTION;
6617 if (targetm.binds_local_p (decl))
6618 flags |= SYMBOL_FLAG_LOCAL;
6619 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6620 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6621 else if (targetm.in_small_data_p (decl))
6622 flags |= SYMBOL_FLAG_SMALL;
6623 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6624 being PUBLIC, the thing *must* be defined in this translation unit.
6625 Prevent this buglet from being propagated into rtl code as well. */
6626 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6627 flags |= SYMBOL_FLAG_EXTERNAL;
6629 SYMBOL_REF_FLAGS (symbol) = flags;
6632 /* By default, we do nothing for encode_section_info, so we need not
6633 do anything but discard the '*' marker. */
6635 const char *
6636 default_strip_name_encoding (const char *str)
6638 return str + (*str == '*');
6641 #ifdef ASM_OUTPUT_DEF
6642 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6643 anchor relative to ".", the current section position. */
6645 void
6646 default_asm_output_anchor (rtx symbol)
6648 char buffer[100];
6650 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6651 SYMBOL_REF_BLOCK_OFFSET (symbol));
6652 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6654 #endif
6656 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6658 bool
6659 default_use_anchors_for_symbol_p (const_rtx symbol)
6661 section *sect;
6662 tree decl;
6664 /* Don't use anchors for mergeable sections. The linker might move
6665 the objects around. */
6666 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6667 if (sect->common.flags & SECTION_MERGE)
6668 return false;
6670 /* Don't use anchors for small data sections. The small data register
6671 acts as an anchor for such sections. */
6672 if (sect->common.flags & SECTION_SMALL)
6673 return false;
6675 decl = SYMBOL_REF_DECL (symbol);
6676 if (decl && DECL_P (decl))
6678 /* Don't use section anchors for decls that might be defined or
6679 usurped by other modules. */
6680 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6681 return false;
6683 /* Don't use section anchors for decls that will be placed in a
6684 small data section. */
6685 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6686 one above. The problem is that we only use SECTION_SMALL for
6687 sections that should be marked as small in the section directive. */
6688 if (targetm.in_small_data_p (decl))
6689 return false;
6691 return true;
6694 /* Return true when RESOLUTION indicate that symbol will be bound to the
6695 definition provided by current .o file. */
6697 static bool
6698 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
6700 return (resolution == LDPR_PREVAILING_DEF
6701 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6702 || resolution == LDPR_PREVAILING_DEF_IRONLY);
6705 /* Return true when RESOLUTION indicate that symbol will be bound locally
6706 within current executable or DSO. */
6708 static bool
6709 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
6711 return (resolution == LDPR_PREVAILING_DEF
6712 || resolution == LDPR_PREVAILING_DEF_IRONLY
6713 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6714 || resolution == LDPR_PREEMPTED_REG
6715 || resolution == LDPR_PREEMPTED_IR
6716 || resolution == LDPR_RESOLVED_IR
6717 || resolution == LDPR_RESOLVED_EXEC);
6720 /* Assume ELF-ish defaults, since that's pretty much the most liberal
6721 wrt cross-module name binding. */
6723 bool
6724 default_binds_local_p (const_tree exp)
6726 return default_binds_local_p_1 (exp, flag_shlib);
6729 bool
6730 default_binds_local_p_1 (const_tree exp, int shlib)
6732 bool local_p;
6733 bool resolved_locally = false;
6734 bool resolved_to_local_def = false;
6736 /* With resolution file in hands, take look into resolutions.
6737 We can't just return true for resolved_locally symbols,
6738 because dynamic linking might overwrite symbols
6739 in shared libraries. */
6740 if (TREE_CODE (exp) == VAR_DECL && TREE_PUBLIC (exp)
6741 && (TREE_STATIC (exp) || DECL_EXTERNAL (exp)))
6743 varpool_node *vnode = varpool_get_node (exp);
6744 if (vnode && (resolution_local_p (vnode->resolution) || vnode->in_other_partition))
6745 resolved_locally = true;
6746 if (vnode
6747 && resolution_to_local_definition_p (vnode->resolution))
6748 resolved_to_local_def = true;
6750 else if (TREE_CODE (exp) == FUNCTION_DECL && TREE_PUBLIC (exp))
6752 struct cgraph_node *node = cgraph_get_node (exp);
6753 if (node
6754 && (resolution_local_p (node->resolution) || node->in_other_partition))
6755 resolved_locally = true;
6756 if (node
6757 && resolution_to_local_definition_p (node->resolution))
6758 resolved_to_local_def = true;
6761 /* A non-decl is an entry in the constant pool. */
6762 if (!DECL_P (exp))
6763 local_p = true;
6764 /* Weakrefs may not bind locally, even though the weakref itself is always
6765 static and therefore local. Similarly, the resolver for ifunc functions
6766 might resolve to a non-local function.
6767 FIXME: We can resolve the weakref case more curefuly by looking at the
6768 weakref alias. */
6769 else if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
6770 || (TREE_CODE (exp) == FUNCTION_DECL
6771 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
6772 local_p = false;
6773 /* Static variables are always local. */
6774 else if (! TREE_PUBLIC (exp))
6775 local_p = true;
6776 /* A variable is local if the user has said explicitly that it will
6777 be. */
6778 else if ((DECL_VISIBILITY_SPECIFIED (exp)
6779 || resolved_to_local_def)
6780 && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6781 local_p = true;
6782 /* Variables defined outside this object might not be local. */
6783 else if (DECL_EXTERNAL (exp) && !resolved_locally)
6784 local_p = false;
6785 /* If defined in this object and visibility is not default, must be
6786 local. */
6787 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6788 local_p = true;
6789 /* Default visibility weak data can be overridden by a strong symbol
6790 in another module and so are not local. */
6791 else if (DECL_WEAK (exp)
6792 && !resolved_locally)
6793 local_p = false;
6794 /* If PIC, then assume that any global name can be overridden by
6795 symbols resolved from other modules. */
6796 else if (shlib)
6797 local_p = false;
6798 /* Uninitialized COMMON variable may be unified with symbols
6799 resolved from other modules. */
6800 else if (DECL_COMMON (exp)
6801 && !resolved_locally
6802 && (DECL_INITIAL (exp) == NULL
6803 || DECL_INITIAL (exp) == error_mark_node))
6804 local_p = false;
6805 /* Otherwise we're left with initialized (or non-common) global data
6806 which is of necessity defined locally. */
6807 else
6808 local_p = true;
6810 return local_p;
6813 /* Return true when references to DECL must bind to current definition in
6814 final executable.
6816 The condition is usually equivalent to whether the function binds to the
6817 current module (shared library or executable), that is to binds_local_p.
6818 We use this fact to avoid need for another target hook and implement
6819 the logic using binds_local_p and just special cases where
6820 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
6821 the weak definitions (that can be overwritten at linktime by other
6822 definition from different object file) and when resolution info is available
6823 we simply use the knowledge passed to us by linker plugin. */
6824 bool
6825 decl_binds_to_current_def_p (tree decl)
6827 gcc_assert (DECL_P (decl));
6828 if (!targetm.binds_local_p (decl))
6829 return false;
6830 if (!TREE_PUBLIC (decl))
6831 return true;
6832 /* When resolution is available, just use it. */
6833 if (TREE_CODE (decl) == VAR_DECL
6834 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl)))
6836 varpool_node *vnode = varpool_get_node (decl);
6837 if (vnode
6838 && vnode->resolution != LDPR_UNKNOWN)
6839 return resolution_to_local_definition_p (vnode->resolution);
6841 else if (TREE_CODE (decl) == FUNCTION_DECL)
6843 struct cgraph_node *node = cgraph_get_node (decl);
6844 if (node
6845 && node->resolution != LDPR_UNKNOWN)
6846 return resolution_to_local_definition_p (node->resolution);
6848 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
6849 binds locally but still can be overwritten), DECL_COMMON (can be merged
6850 with a non-common definition somewhere in the same module) or
6851 DECL_EXTERNAL.
6852 This rely on fact that binds_local_p behave as decl_replaceable_p
6853 for all other declaration types. */
6854 if (DECL_WEAK (decl))
6855 return false;
6856 if (DECL_COMMON (decl)
6857 && (DECL_INITIAL (decl) == NULL
6858 || DECL_INITIAL (decl) == error_mark_node))
6859 return false;
6860 if (DECL_EXTERNAL (decl))
6861 return false;
6862 return true;
6865 /* A replaceable function or variable is one which may be replaced
6866 at link-time with an entirely different definition, provided that the
6867 replacement has the same type. For example, functions declared
6868 with __attribute__((weak)) on most systems are replaceable.
6870 COMDAT functions are not replaceable, since all definitions of the
6871 function must be equivalent. It is important that COMDAT functions
6872 not be treated as replaceable so that use of C++ template
6873 instantiations is not penalized. */
6875 bool
6876 decl_replaceable_p (tree decl)
6878 gcc_assert (DECL_P (decl));
6879 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
6880 return false;
6881 return !decl_binds_to_current_def_p (decl);
6884 /* Default function to output code that will globalize a label. A
6885 target must define GLOBAL_ASM_OP or provide its own function to
6886 globalize a label. */
6887 #ifdef GLOBAL_ASM_OP
6888 void
6889 default_globalize_label (FILE * stream, const char *name)
6891 fputs (GLOBAL_ASM_OP, stream);
6892 assemble_name (stream, name);
6893 putc ('\n', stream);
6895 #endif /* GLOBAL_ASM_OP */
6897 /* Default function to output code that will globalize a declaration. */
6898 void
6899 default_globalize_decl_name (FILE * stream, tree decl)
6901 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
6902 targetm.asm_out.globalize_label (stream, name);
6905 /* Default function to output a label for unwind information. The
6906 default is to do nothing. A target that needs nonlocal labels for
6907 unwind information must provide its own function to do this. */
6908 void
6909 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
6910 tree decl ATTRIBUTE_UNUSED,
6911 int for_eh ATTRIBUTE_UNUSED,
6912 int empty ATTRIBUTE_UNUSED)
6916 /* Default function to output a label to divide up the exception table.
6917 The default is to do nothing. A target that needs/wants to divide
6918 up the table must provide it's own function to do this. */
6919 void
6920 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
6924 /* This is how to output an internal numbered label where PREFIX is
6925 the class of label and LABELNO is the number within the class. */
6927 void
6928 default_generate_internal_label (char *buf, const char *prefix,
6929 unsigned long labelno)
6931 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6934 /* This is how to output an internal numbered label where PREFIX is
6935 the class of label and LABELNO is the number within the class. */
6937 void
6938 default_internal_label (FILE *stream, const char *prefix,
6939 unsigned long labelno)
6941 char *const buf = (char *) alloca (40 + strlen (prefix));
6942 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6943 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
6947 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
6949 void
6950 default_asm_declare_constant_name (FILE *file, const char *name,
6951 const_tree exp ATTRIBUTE_UNUSED,
6952 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
6954 assemble_label (file, name);
6957 /* This is the default behavior at the beginning of a file. It's
6958 controlled by two other target-hook toggles. */
6959 void
6960 default_file_start (void)
6962 if (targetm.asm_file_start_app_off
6963 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
6964 fputs (ASM_APP_OFF, asm_out_file);
6966 if (targetm.asm_file_start_file_directive)
6967 output_file_directive (asm_out_file, main_input_filename);
6970 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
6971 which emits a special section directive used to indicate whether or
6972 not this object file needs an executable stack. This is primarily
6973 a GNU extension to ELF but could be used on other targets. */
6975 int trampolines_created;
6977 void
6978 file_end_indicate_exec_stack (void)
6980 unsigned int flags = SECTION_DEBUG;
6981 if (trampolines_created)
6982 flags |= SECTION_CODE;
6984 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
6987 /* Emit a special section directive to indicate that this object file
6988 was compiled with -fsplit-stack. This is used to let the linker
6989 detect calls between split-stack code and non-split-stack code, so
6990 that it can modify the split-stack code to allocate a sufficiently
6991 large stack. We emit another special section if there are any
6992 functions in this file which have the no_split_stack attribute, to
6993 prevent the linker from warning about being unable to convert the
6994 functions if they call non-split-stack code. */
6996 void
6997 file_end_indicate_split_stack (void)
6999 if (flag_split_stack)
7001 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
7002 NULL));
7003 if (saw_no_split_stack)
7004 switch_to_section (get_section (".note.GNU-no-split-stack",
7005 SECTION_DEBUG, NULL));
7009 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
7010 a get_unnamed_section callback. */
7012 void
7013 output_section_asm_op (const void *directive)
7015 fprintf (asm_out_file, "%s\n", (const char *) directive);
7018 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
7019 the current section is NEW_SECTION. */
7021 void
7022 switch_to_section (section *new_section)
7024 if (in_section == new_section)
7025 return;
7027 if (new_section->common.flags & SECTION_FORGET)
7028 in_section = NULL;
7029 else
7030 in_section = new_section;
7032 switch (SECTION_STYLE (new_section))
7034 case SECTION_NAMED:
7035 targetm.asm_out.named_section (new_section->named.name,
7036 new_section->named.common.flags,
7037 new_section->named.decl);
7038 break;
7040 case SECTION_UNNAMED:
7041 new_section->unnamed.callback (new_section->unnamed.data);
7042 break;
7044 case SECTION_NOSWITCH:
7045 gcc_unreachable ();
7046 break;
7049 new_section->common.flags |= SECTION_DECLARED;
7052 /* If block symbol SYMBOL has not yet been assigned an offset, place
7053 it at the end of its block. */
7055 void
7056 place_block_symbol (rtx symbol)
7058 unsigned HOST_WIDE_INT size, mask, offset;
7059 struct constant_descriptor_rtx *desc;
7060 unsigned int alignment;
7061 struct object_block *block;
7062 tree decl;
7064 gcc_assert (SYMBOL_REF_BLOCK (symbol));
7065 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7066 return;
7068 /* Work out the symbol's size and alignment. */
7069 if (CONSTANT_POOL_ADDRESS_P (symbol))
7071 desc = SYMBOL_REF_CONSTANT (symbol);
7072 alignment = desc->align;
7073 size = GET_MODE_SIZE (desc->mode);
7075 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7077 decl = SYMBOL_REF_DECL (symbol);
7078 alignment = DECL_ALIGN (decl);
7079 size = get_constant_size (DECL_INITIAL (decl));
7080 if ((flag_sanitize & SANITIZE_ADDRESS)
7081 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7082 && asan_protect_global (DECL_INITIAL (decl)))
7083 size += asan_red_zone_size (size);
7085 else
7087 decl = SYMBOL_REF_DECL (symbol);
7088 alignment = get_variable_align (decl);
7089 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7090 if ((flag_sanitize & SANITIZE_ADDRESS)
7091 && asan_protect_global (decl))
7093 size += asan_red_zone_size (size);
7094 alignment = MAX (alignment,
7095 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7099 /* Calculate the object's offset from the start of the block. */
7100 block = SYMBOL_REF_BLOCK (symbol);
7101 mask = alignment / BITS_PER_UNIT - 1;
7102 offset = (block->size + mask) & ~mask;
7103 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7105 /* Record the block's new alignment and size. */
7106 block->alignment = MAX (block->alignment, alignment);
7107 block->size = offset + size;
7109 vec_safe_push (block->objects, symbol);
7112 /* Return the anchor that should be used to address byte offset OFFSET
7113 from the first object in BLOCK. MODEL is the TLS model used
7114 to access it. */
7117 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7118 enum tls_model model)
7120 char label[100];
7121 unsigned int begin, middle, end;
7122 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7123 rtx anchor;
7125 /* Work out the anchor's offset. Use an offset of 0 for the first
7126 anchor so that we don't pessimize the case where we take the address
7127 of a variable at the beginning of the block. This is particularly
7128 useful when a block has only one variable assigned to it.
7130 We try to place anchors RANGE bytes apart, so there can then be
7131 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7132 a ptr_mode offset. With some target settings, the lowest such
7133 anchor might be out of range for the lowest ptr_mode offset;
7134 likewise the highest anchor for the highest offset. Use anchors
7135 at the extreme ends of the ptr_mode range in such cases.
7137 All arithmetic uses unsigned integers in order to avoid
7138 signed overflow. */
7139 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7140 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7141 range = max_offset - min_offset + 1;
7142 if (range == 0)
7143 offset = 0;
7144 else
7146 bias = 1 << (GET_MODE_BITSIZE (ptr_mode) - 1);
7147 if (offset < 0)
7149 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7150 delta -= delta % range;
7151 if (delta > bias)
7152 delta = bias;
7153 offset = (HOST_WIDE_INT) (-delta);
7155 else
7157 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7158 delta -= delta % range;
7159 if (delta > bias - 1)
7160 delta = bias - 1;
7161 offset = (HOST_WIDE_INT) delta;
7165 /* Do a binary search to see if there's already an anchor we can use.
7166 Set BEGIN to the new anchor's index if not. */
7167 begin = 0;
7168 end = vec_safe_length (block->anchors);
7169 while (begin != end)
7171 middle = (end + begin) / 2;
7172 anchor = (*block->anchors)[middle];
7173 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7174 end = middle;
7175 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7176 begin = middle + 1;
7177 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7178 end = middle;
7179 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7180 begin = middle + 1;
7181 else
7182 return anchor;
7185 /* Create a new anchor with a unique label. */
7186 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7187 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7188 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7189 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7191 /* Insert it at index BEGIN. */
7192 vec_safe_insert (block->anchors, begin, anchor);
7193 return anchor;
7196 /* Output the objects in BLOCK. */
7198 static void
7199 output_object_block (struct object_block *block)
7201 struct constant_descriptor_rtx *desc;
7202 unsigned int i;
7203 HOST_WIDE_INT offset;
7204 tree decl;
7205 rtx symbol;
7207 if (!block->objects)
7208 return;
7210 /* Switch to the section and make sure that the first byte is
7211 suitably aligned. */
7212 switch_to_section (block->sect);
7213 assemble_align (block->alignment);
7215 /* Define the values of all anchors relative to the current section
7216 position. */
7217 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7218 targetm.asm_out.output_anchor (symbol);
7220 /* Output the objects themselves. */
7221 offset = 0;
7222 FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7224 /* Move to the object's offset, padding with zeros if necessary. */
7225 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7226 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7227 if (CONSTANT_POOL_ADDRESS_P (symbol))
7229 desc = SYMBOL_REF_CONSTANT (symbol);
7230 output_constant_pool_1 (desc, 1);
7231 offset += GET_MODE_SIZE (desc->mode);
7233 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7235 HOST_WIDE_INT size;
7236 decl = SYMBOL_REF_DECL (symbol);
7237 assemble_constant_contents (DECL_INITIAL (decl), XSTR (symbol, 0),
7238 DECL_ALIGN (decl));
7239 size = get_constant_size (DECL_INITIAL (decl));
7240 offset += size;
7241 if ((flag_sanitize & SANITIZE_ADDRESS)
7242 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7243 && asan_protect_global (DECL_INITIAL (decl)))
7245 size = asan_red_zone_size (size);
7246 assemble_zeros (size);
7247 offset += size;
7250 else
7252 HOST_WIDE_INT size;
7253 decl = SYMBOL_REF_DECL (symbol);
7254 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7255 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7256 offset += size;
7257 if ((flag_sanitize & SANITIZE_ADDRESS)
7258 && asan_protect_global (decl))
7260 size = asan_red_zone_size (size);
7261 assemble_zeros (size);
7262 offset += size;
7268 /* A htab_traverse callback used to call output_object_block for
7269 each member of object_block_htab. */
7271 static int
7272 output_object_block_htab (void **slot, void *data ATTRIBUTE_UNUSED)
7274 output_object_block ((struct object_block *) (*slot));
7275 return 1;
7278 /* Output the definitions of all object_blocks. */
7280 void
7281 output_object_blocks (void)
7283 htab_traverse (object_block_htab, output_object_block_htab, NULL);
7286 /* This function provides a possible implementation of the
7287 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7288 by -frecord-gcc-switches it creates a new mergeable, string section in the
7289 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7290 contains the switches in ASCII format.
7292 FIXME: This code does not correctly handle double quote characters
7293 that appear inside strings, (it strips them rather than preserving them).
7294 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7295 characters - instead it treats them as sub-string separators. Since
7296 we want to emit NUL strings terminators into the object file we have to use
7297 ASM_OUTPUT_SKIP. */
7300 elf_record_gcc_switches (print_switch_type type, const char * name)
7302 switch (type)
7304 case SWITCH_TYPE_PASSED:
7305 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7306 ASM_OUTPUT_SKIP (asm_out_file, (unsigned HOST_WIDE_INT) 1);
7307 break;
7309 case SWITCH_TYPE_DESCRIPTIVE:
7310 if (name == NULL)
7312 /* Distinguish between invocations where name is NULL. */
7313 static bool started = false;
7315 if (!started)
7317 section * sec;
7319 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7320 SECTION_DEBUG
7321 | SECTION_MERGE
7322 | SECTION_STRINGS
7323 | (SECTION_ENTSIZE & 1),
7324 NULL);
7325 switch_to_section (sec);
7326 started = true;
7330 default:
7331 break;
7334 /* The return value is currently ignored by the caller, but must be 0.
7335 For -fverbose-asm the return value would be the number of characters
7336 emitted into the assembler file. */
7337 return 0;
7340 /* Emit text to declare externally defined symbols. It is needed to
7341 properly support non-default visibility. */
7342 void
7343 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7344 tree decl,
7345 const char *name ATTRIBUTE_UNUSED)
7347 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7348 set in order to avoid putting out names that are never really
7349 used. */
7350 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7351 && targetm.binds_local_p (decl))
7352 maybe_assemble_visibility (decl);
7355 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7357 void
7358 default_asm_output_source_filename (FILE *file, const char *name)
7360 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7361 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7362 #else
7363 fprintf (file, "\t.file\t");
7364 output_quoted_string (file, name);
7365 putc ('\n', file);
7366 #endif
7369 /* Output a file name in the form wanted by System V. */
7371 void
7372 output_file_directive (FILE *asm_file, const char *input_name)
7374 int len;
7375 const char *na;
7377 if (input_name == NULL)
7378 input_name = "<stdin>";
7379 else
7380 input_name = remap_debug_filename (input_name);
7382 len = strlen (input_name);
7383 na = input_name + len;
7385 /* NA gets INPUT_NAME sans directory names. */
7386 while (na > input_name)
7388 if (IS_DIR_SEPARATOR (na[-1]))
7389 break;
7390 na--;
7393 targetm.asm_out.output_source_filename (asm_file, na);
7396 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7397 EXP. */
7399 make_debug_expr_from_rtl (const_rtx exp)
7401 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7402 enum machine_mode mode = GET_MODE (exp);
7403 rtx dval;
7405 DECL_ARTIFICIAL (ddecl) = 1;
7406 if (REG_P (exp) && REG_EXPR (exp))
7407 type = TREE_TYPE (REG_EXPR (exp));
7408 else if (MEM_P (exp) && MEM_EXPR (exp))
7409 type = TREE_TYPE (MEM_EXPR (exp));
7410 else
7411 type = NULL_TREE;
7412 if (type && TYPE_MODE (type) == mode)
7413 TREE_TYPE (ddecl) = type;
7414 else
7415 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7416 DECL_MODE (ddecl) = mode;
7417 dval = gen_rtx_DEBUG_EXPR (mode);
7418 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7419 SET_DECL_RTL (ddecl, dval);
7420 return dval;
7423 #ifdef ELF_ASCII_ESCAPES
7424 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7426 void
7427 default_elf_asm_output_limited_string (FILE *f, const char *s)
7429 int escape;
7430 unsigned char c;
7432 fputs (STRING_ASM_OP, f);
7433 putc ('"', f);
7434 while (*s != '\0')
7436 c = *s;
7437 escape = ELF_ASCII_ESCAPES[c];
7438 switch (escape)
7440 case 0:
7441 putc (c, f);
7442 break;
7443 case 1:
7444 /* TODO: Print in hex with fast function, important for -flto. */
7445 fprintf (f, "\\%03o", c);
7446 break;
7447 default:
7448 putc ('\\', f);
7449 putc (escape, f);
7450 break;
7452 s++;
7454 putc ('\"', f);
7455 putc ('\n', f);
7458 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7460 void
7461 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7463 const char *limit = s + len;
7464 const char *last_null = NULL;
7465 unsigned bytes_in_chunk = 0;
7466 unsigned char c;
7467 int escape;
7469 for (; s < limit; s++)
7471 const char *p;
7473 if (bytes_in_chunk >= 60)
7475 putc ('\"', f);
7476 putc ('\n', f);
7477 bytes_in_chunk = 0;
7480 if (s > last_null)
7482 for (p = s; p < limit && *p != '\0'; p++)
7483 continue;
7484 last_null = p;
7486 else
7487 p = last_null;
7489 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7491 if (bytes_in_chunk > 0)
7493 putc ('\"', f);
7494 putc ('\n', f);
7495 bytes_in_chunk = 0;
7498 default_elf_asm_output_limited_string (f, s);
7499 s = p;
7501 else
7503 if (bytes_in_chunk == 0)
7504 fputs (ASCII_DATA_ASM_OP "\"", f);
7506 c = *s;
7507 escape = ELF_ASCII_ESCAPES[c];
7508 switch (escape)
7510 case 0:
7511 putc (c, f);
7512 bytes_in_chunk++;
7513 break;
7514 case 1:
7515 /* TODO: Print in hex with fast function, important for -flto. */
7516 fprintf (f, "\\%03o", c);
7517 bytes_in_chunk += 4;
7518 break;
7519 default:
7520 putc ('\\', f);
7521 putc (escape, f);
7522 bytes_in_chunk += 2;
7523 break;
7529 if (bytes_in_chunk > 0)
7531 putc ('\"', f);
7532 putc ('\n', f);
7535 #endif
7537 static GTY(()) section *elf_init_array_section;
7538 static GTY(()) section *elf_fini_array_section;
7540 static section *
7541 get_elf_initfini_array_priority_section (int priority,
7542 bool constructor_p)
7544 section *sec;
7545 if (priority != DEFAULT_INIT_PRIORITY)
7547 char buf[18];
7548 sprintf (buf, "%s.%.5u",
7549 constructor_p ? ".init_array" : ".fini_array",
7550 priority);
7551 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7553 else
7555 if (constructor_p)
7557 if (elf_init_array_section == NULL)
7558 elf_init_array_section
7559 = get_section (".init_array",
7560 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7561 sec = elf_init_array_section;
7563 else
7565 if (elf_fini_array_section == NULL)
7566 elf_fini_array_section
7567 = get_section (".fini_array",
7568 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7569 sec = elf_fini_array_section;
7572 return sec;
7575 /* Use .init_array section for constructors. */
7577 void
7578 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7580 section *sec = get_elf_initfini_array_priority_section (priority,
7581 true);
7582 assemble_addr_to_section (symbol, sec);
7585 /* Use .fini_array section for destructors. */
7587 void
7588 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7590 section *sec = get_elf_initfini_array_priority_section (priority,
7591 false);
7592 assemble_addr_to_section (symbol, sec);
7595 /* Default TARGET_ASM_OUTPUT_IDENT hook.
7597 This is a bit of a cheat. The real default is a no-op, but this
7598 hook is the default for all targets with a .ident directive. */
7600 void
7601 default_asm_output_ident_directive (const char *ident_str)
7603 const char *ident_asm_op = "\t.ident\t";
7605 /* If we are still in the front end, do not write out the string
7606 to asm_out_file. Instead, add a fake top-level asm statement.
7607 This allows the front ends to use this hook without actually
7608 writing to asm_out_file, to handle #ident or Pragma Ident. */
7609 if (cgraph_state == CGRAPH_STATE_PARSING)
7611 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
7612 add_asm_node (build_string (strlen (buf), buf));
7614 else
7615 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
7618 #include "gt-varasm.h"