* g++.dg/asan/asan_test.C: Add -std=c++11 and
[official-gcc.git] / gcc / varasm.c
blob7755717fe2792e5f91c461a734e941a37f723213
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_cleared_alloc<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 = (rtx) ggc_internal_alloc (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_COMDAT_GROUP (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_COMDAT_GROUP (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_COMDAT_GROUP (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_COMDAT_GROUP (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)
1000 && !DECL_VIRTUAL_P (decl))
1002 #ifdef DATA_ALIGNMENT
1003 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1004 /* Don't increase alignment too much for TLS variables - TLS space
1005 is too precious. */
1006 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1007 align = data_align;
1008 #endif
1009 #ifdef CONSTANT_ALIGNMENT
1010 if (DECL_INITIAL (decl) != 0
1011 && DECL_INITIAL (decl) != error_mark_node)
1013 unsigned int const_align
1014 = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
1015 /* Don't increase alignment too much for TLS variables - TLS
1016 space is too precious. */
1017 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1018 align = const_align;
1020 #endif
1024 /* Reset the alignment in case we have made it tighter, so we can benefit
1025 from it in get_pointer_alignment. */
1026 DECL_ALIGN (decl) = align;
1029 /* Return DECL_ALIGN (decl), possibly increased for optimization purposes
1030 beyond what align_variable returned. */
1032 static unsigned int
1033 get_variable_align (tree decl)
1035 unsigned int align = DECL_ALIGN (decl);
1037 /* For user aligned vars or static vars align_variable already did
1038 everything. */
1039 if (DECL_USER_ALIGN (decl) || !TREE_PUBLIC (decl))
1040 return align;
1042 #ifdef DATA_ABI_ALIGNMENT
1043 if (DECL_THREAD_LOCAL_P (decl))
1044 align = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1045 #endif
1047 /* For decls that bind to the current definition, align_variable
1048 did also everything, except for not assuming ABI required alignment
1049 of TLS variables. For other vars, increase the alignment here
1050 as an optimization. */
1051 if (!decl_binds_to_current_def_p (decl))
1053 /* On some machines, it is good to increase alignment sometimes. */
1054 #ifdef DATA_ALIGNMENT
1055 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1056 /* Don't increase alignment too much for TLS variables - TLS space
1057 is too precious. */
1058 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1059 align = data_align;
1060 #endif
1061 #ifdef CONSTANT_ALIGNMENT
1062 if (DECL_INITIAL (decl) != 0 && DECL_INITIAL (decl) != error_mark_node)
1064 unsigned int const_align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl),
1065 align);
1066 /* Don't increase alignment too much for TLS variables - TLS space
1067 is too precious. */
1068 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1069 align = const_align;
1071 #endif
1074 return align;
1077 /* Return the section into which the given VAR_DECL or CONST_DECL
1078 should be placed. PREFER_NOSWITCH_P is true if a noswitch
1079 section should be used wherever possible. */
1081 section *
1082 get_variable_section (tree decl, bool prefer_noswitch_p)
1084 addr_space_t as = ADDR_SPACE_GENERIC;
1085 int reloc;
1086 symtab_node *snode = symtab_get_node (decl);
1087 if (snode)
1088 decl = symtab_alias_ultimate_target (snode)->decl;
1090 if (TREE_TYPE (decl) != error_mark_node)
1091 as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1093 if (DECL_COMMON (decl))
1095 /* If the decl has been given an explicit section name, or it resides
1096 in a non-generic address space, then it isn't common, and shouldn't
1097 be handled as such. */
1098 gcc_assert (DECL_SECTION_NAME (decl) == NULL
1099 && ADDR_SPACE_GENERIC_P (as));
1100 if (DECL_THREAD_LOCAL_P (decl))
1101 return tls_comm_section;
1102 else if (TREE_PUBLIC (decl) && bss_initializer_p (decl))
1103 return comm_section;
1106 if (DECL_INITIAL (decl) == error_mark_node)
1107 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1108 else if (DECL_INITIAL (decl))
1109 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1110 else
1111 reloc = 0;
1113 resolve_unique_section (decl, reloc, flag_data_sections);
1114 if (IN_NAMED_SECTION (decl))
1115 return get_named_section (decl, NULL, reloc);
1117 if (ADDR_SPACE_GENERIC_P (as)
1118 && !DECL_THREAD_LOCAL_P (decl)
1119 && !(prefer_noswitch_p && targetm.have_switchable_bss_sections)
1120 && bss_initializer_p (decl))
1122 if (!TREE_PUBLIC (decl)
1123 && !((flag_sanitize & SANITIZE_ADDRESS)
1124 && asan_protect_global (decl)))
1125 return lcomm_section;
1126 if (bss_noswitch_section)
1127 return bss_noswitch_section;
1130 return targetm.asm_out.select_section (decl, reloc,
1131 get_variable_align (decl));
1134 /* Return the block into which object_block DECL should be placed. */
1136 static struct object_block *
1137 get_block_for_decl (tree decl)
1139 section *sect;
1141 if (TREE_CODE (decl) == VAR_DECL)
1143 /* The object must be defined in this translation unit. */
1144 if (DECL_EXTERNAL (decl))
1145 return NULL;
1147 /* There's no point using object blocks for something that is
1148 isolated by definition. */
1149 if (DECL_COMDAT_GROUP (decl))
1150 return NULL;
1153 /* We can only calculate block offsets if the decl has a known
1154 constant size. */
1155 if (DECL_SIZE_UNIT (decl) == NULL)
1156 return NULL;
1157 if (!tree_fits_uhwi_p (DECL_SIZE_UNIT (decl)))
1158 return NULL;
1160 /* Find out which section should contain DECL. We cannot put it into
1161 an object block if it requires a standalone definition. */
1162 if (TREE_CODE (decl) == VAR_DECL)
1163 align_variable (decl, 0);
1164 sect = get_variable_section (decl, true);
1165 if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
1166 return NULL;
1168 return get_block_for_section (sect);
1171 /* Make sure block symbol SYMBOL is in block BLOCK. */
1173 static void
1174 change_symbol_block (rtx symbol, struct object_block *block)
1176 if (block != SYMBOL_REF_BLOCK (symbol))
1178 gcc_assert (SYMBOL_REF_BLOCK_OFFSET (symbol) < 0);
1179 SYMBOL_REF_BLOCK (symbol) = block;
1183 /* Return true if it is possible to put DECL in an object_block. */
1185 static bool
1186 use_blocks_for_decl_p (tree decl)
1188 /* Only data DECLs can be placed into object blocks. */
1189 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != CONST_DECL)
1190 return false;
1192 /* Detect decls created by dw2_force_const_mem. Such decls are
1193 special because DECL_INITIAL doesn't specify the decl's true value.
1194 dw2_output_indirect_constants will instead call assemble_variable
1195 with dont_output_data set to 1 and then print the contents itself. */
1196 if (DECL_INITIAL (decl) == decl)
1197 return false;
1199 /* If this decl is an alias, then we don't want to emit a
1200 definition. */
1201 if (lookup_attribute ("alias", DECL_ATTRIBUTES (decl)))
1202 return false;
1204 return targetm.use_blocks_for_decl_p (decl);
1207 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
1208 have static storage duration. In other words, it should not be an
1209 automatic variable, including PARM_DECLs.
1211 There is, however, one exception: this function handles variables
1212 explicitly placed in a particular register by the user.
1214 This is never called for PARM_DECL nodes. */
1216 void
1217 make_decl_rtl (tree decl)
1219 const char *name = 0;
1220 int reg_number;
1221 rtx x;
1223 /* Check that we are not being given an automatic variable. */
1224 gcc_assert (TREE_CODE (decl) != PARM_DECL
1225 && TREE_CODE (decl) != RESULT_DECL);
1227 /* A weak alias has TREE_PUBLIC set but not the other bits. */
1228 gcc_assert (TREE_CODE (decl) != VAR_DECL
1229 || TREE_STATIC (decl)
1230 || TREE_PUBLIC (decl)
1231 || DECL_EXTERNAL (decl)
1232 || DECL_REGISTER (decl));
1234 /* And that we were not given a type or a label. */
1235 gcc_assert (TREE_CODE (decl) != TYPE_DECL
1236 && TREE_CODE (decl) != LABEL_DECL);
1238 /* For a duplicate declaration, we can be called twice on the
1239 same DECL node. Don't discard the RTL already made. */
1240 if (DECL_RTL_SET_P (decl))
1242 /* If the old RTL had the wrong mode, fix the mode. */
1243 x = DECL_RTL (decl);
1244 if (GET_MODE (x) != DECL_MODE (decl))
1245 SET_DECL_RTL (decl, adjust_address_nv (x, DECL_MODE (decl), 0));
1247 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1248 return;
1250 /* ??? Another way to do this would be to maintain a hashed
1251 table of such critters. Instead of adding stuff to a DECL
1252 to give certain attributes to it, we could use an external
1253 hash map from DECL to set of attributes. */
1255 /* Let the target reassign the RTL if it wants.
1256 This is necessary, for example, when one machine specific
1257 decl attribute overrides another. */
1258 targetm.encode_section_info (decl, DECL_RTL (decl), false);
1260 /* If the symbol has a SYMBOL_REF_BLOCK field, update it based
1261 on the new decl information. */
1262 if (MEM_P (x)
1263 && GET_CODE (XEXP (x, 0)) == SYMBOL_REF
1264 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (x, 0)))
1265 change_symbol_block (XEXP (x, 0), get_block_for_decl (decl));
1267 return;
1270 /* If this variable belongs to the global constant pool, retrieve the
1271 pre-computed RTL or recompute it in LTO mode. */
1272 if (TREE_CODE (decl) == VAR_DECL && DECL_IN_CONSTANT_POOL (decl))
1274 SET_DECL_RTL (decl, output_constant_def (DECL_INITIAL (decl), 1));
1275 return;
1278 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
1280 if (name[0] != '*' && TREE_CODE (decl) != FUNCTION_DECL
1281 && DECL_REGISTER (decl))
1283 error ("register name not specified for %q+D", decl);
1285 else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1287 const char *asmspec = name+1;
1288 enum machine_mode mode = DECL_MODE (decl);
1289 reg_number = decode_reg_name (asmspec);
1290 /* First detect errors in declaring global registers. */
1291 if (reg_number == -1)
1292 error ("register name not specified for %q+D", decl);
1293 else if (reg_number < 0)
1294 error ("invalid register name for %q+D", decl);
1295 else if (mode == BLKmode)
1296 error ("data type of %q+D isn%'t suitable for a register",
1297 decl);
1298 else if (!in_hard_reg_set_p (accessible_reg_set, mode, reg_number))
1299 error ("the register specified for %q+D cannot be accessed"
1300 " by the current target", decl);
1301 else if (!in_hard_reg_set_p (operand_reg_set, mode, reg_number))
1302 error ("the register specified for %q+D is not general enough"
1303 " to be used as a register variable", decl);
1304 else if (!HARD_REGNO_MODE_OK (reg_number, mode))
1305 error ("register specified for %q+D isn%'t suitable for data type",
1306 decl);
1307 /* Now handle properly declared static register variables. */
1308 else
1310 int nregs;
1312 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
1314 DECL_INITIAL (decl) = 0;
1315 error ("global register variable has initial value");
1317 if (TREE_THIS_VOLATILE (decl))
1318 warning (OPT_Wvolatile_register_var,
1319 "optimization may eliminate reads and/or "
1320 "writes to register variables");
1322 /* If the user specified one of the eliminables registers here,
1323 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
1324 confused with that register and be eliminated. This usage is
1325 somewhat suspect... */
1327 SET_DECL_RTL (decl, gen_rtx_raw_REG (mode, reg_number));
1328 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
1329 REG_USERVAR_P (DECL_RTL (decl)) = 1;
1331 if (TREE_STATIC (decl))
1333 /* Make this register global, so not usable for anything
1334 else. */
1335 #ifdef ASM_DECLARE_REGISTER_GLOBAL
1336 name = IDENTIFIER_POINTER (DECL_NAME (decl));
1337 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
1338 #endif
1339 nregs = hard_regno_nregs[reg_number][mode];
1340 while (nregs > 0)
1341 globalize_reg (decl, reg_number + --nregs);
1344 /* As a register variable, it has no section. */
1345 return;
1348 /* Now handle ordinary static variables and functions (in memory).
1349 Also handle vars declared register invalidly. */
1350 else if (name[0] == '*')
1352 #ifdef REGISTER_PREFIX
1353 if (strlen (REGISTER_PREFIX) != 0)
1355 reg_number = decode_reg_name (name);
1356 if (reg_number >= 0 || reg_number == -3)
1357 error ("register name given for non-register variable %q+D", decl);
1359 #endif
1362 /* Specifying a section attribute on a variable forces it into a
1363 non-.bss section, and thus it cannot be common. */
1364 /* FIXME: In general this code should not be necessary because
1365 visibility pass is doing the same work. But notice_global_symbol
1366 is called early and it needs to make DECL_RTL to get the name.
1367 we take care of recomputing the DECL_RTL after visibility is changed. */
1368 if (TREE_CODE (decl) == VAR_DECL
1369 && DECL_SECTION_NAME (decl) != NULL_TREE
1370 && DECL_INITIAL (decl) == NULL_TREE
1371 && DECL_COMMON (decl))
1372 DECL_COMMON (decl) = 0;
1374 /* Variables can't be both common and weak. */
1375 if (TREE_CODE (decl) == VAR_DECL && DECL_WEAK (decl))
1376 DECL_COMMON (decl) = 0;
1378 if (use_object_blocks_p () && use_blocks_for_decl_p (decl))
1379 x = create_block_symbol (name, get_block_for_decl (decl), -1);
1380 else
1382 enum machine_mode address_mode = Pmode;
1383 if (TREE_TYPE (decl) != error_mark_node)
1385 addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1386 address_mode = targetm.addr_space.address_mode (as);
1388 x = gen_rtx_SYMBOL_REF (address_mode, name);
1390 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
1391 SET_SYMBOL_REF_DECL (x, decl);
1393 x = gen_rtx_MEM (DECL_MODE (decl), x);
1394 if (TREE_CODE (decl) != FUNCTION_DECL)
1395 set_mem_attributes (x, decl, 1);
1396 SET_DECL_RTL (decl, x);
1398 /* Optionally set flags or add text to the name to record information
1399 such as that it is a function name.
1400 If the name is changed, the macro ASM_OUTPUT_LABELREF
1401 will have to know how to strip this information. */
1402 targetm.encode_section_info (decl, DECL_RTL (decl), true);
1405 /* Like make_decl_rtl, but inhibit creation of new alias sets when
1406 calling make_decl_rtl. Also, reset DECL_RTL before returning the
1407 rtl. */
1410 make_decl_rtl_for_debug (tree decl)
1412 unsigned int save_aliasing_flag;
1413 rtx rtl;
1415 if (DECL_RTL_SET_P (decl))
1416 return DECL_RTL (decl);
1418 /* Kludge alert! Somewhere down the call chain, make_decl_rtl will
1419 call new_alias_set. If running with -fcompare-debug, sometimes
1420 we do not want to create alias sets that will throw the alias
1421 numbers off in the comparison dumps. So... clearing
1422 flag_strict_aliasing will keep new_alias_set() from creating a
1423 new set. */
1424 save_aliasing_flag = flag_strict_aliasing;
1425 flag_strict_aliasing = 0;
1427 rtl = DECL_RTL (decl);
1428 /* Reset DECL_RTL back, as various parts of the compiler expects
1429 DECL_RTL set meaning it is actually going to be output. */
1430 SET_DECL_RTL (decl, NULL);
1432 flag_strict_aliasing = save_aliasing_flag;
1433 return rtl;
1436 /* Output a string of literal assembler code
1437 for an `asm' keyword used between functions. */
1439 void
1440 assemble_asm (tree string)
1442 const char *p;
1443 app_enable ();
1445 if (TREE_CODE (string) == ADDR_EXPR)
1446 string = TREE_OPERAND (string, 0);
1448 p = TREE_STRING_POINTER (string);
1449 fprintf (asm_out_file, "%s%s\n", p[0] == '\t' ? "" : "\t", p);
1452 /* Write the address of the entity given by SYMBOL to SEC. */
1453 void
1454 assemble_addr_to_section (rtx symbol, section *sec)
1456 switch_to_section (sec);
1457 assemble_align (POINTER_SIZE);
1458 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1461 /* Return the numbered .ctors.N (if CONSTRUCTOR_P) or .dtors.N (if
1462 not) section for PRIORITY. */
1463 section *
1464 get_cdtor_priority_section (int priority, bool constructor_p)
1466 char buf[16];
1468 /* ??? This only works reliably with the GNU linker. */
1469 sprintf (buf, "%s.%.5u",
1470 constructor_p ? ".ctors" : ".dtors",
1471 /* Invert the numbering so the linker puts us in the proper
1472 order; constructors are run from right to left, and the
1473 linker sorts in increasing order. */
1474 MAX_INIT_PRIORITY - priority);
1475 return get_section (buf, SECTION_WRITE, NULL);
1478 void
1479 default_named_section_asm_out_destructor (rtx symbol, int priority)
1481 section *sec;
1483 if (priority != DEFAULT_INIT_PRIORITY)
1484 sec = get_cdtor_priority_section (priority,
1485 /*constructor_p=*/false);
1486 else
1487 sec = get_section (".dtors", SECTION_WRITE, NULL);
1489 assemble_addr_to_section (symbol, sec);
1492 #ifdef DTORS_SECTION_ASM_OP
1493 void
1494 default_dtor_section_asm_out_destructor (rtx symbol,
1495 int priority ATTRIBUTE_UNUSED)
1497 assemble_addr_to_section (symbol, dtors_section);
1499 #endif
1501 void
1502 default_named_section_asm_out_constructor (rtx symbol, int priority)
1504 section *sec;
1506 if (priority != DEFAULT_INIT_PRIORITY)
1507 sec = get_cdtor_priority_section (priority,
1508 /*constructor_p=*/true);
1509 else
1510 sec = get_section (".ctors", SECTION_WRITE, NULL);
1512 assemble_addr_to_section (symbol, sec);
1515 #ifdef CTORS_SECTION_ASM_OP
1516 void
1517 default_ctor_section_asm_out_constructor (rtx symbol,
1518 int priority ATTRIBUTE_UNUSED)
1520 assemble_addr_to_section (symbol, ctors_section);
1522 #endif
1524 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1525 a nonzero value if the constant pool should be output before the
1526 start of the function, or a zero value if the pool should output
1527 after the end of the function. The default is to put it before the
1528 start. */
1530 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1531 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1532 #endif
1534 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1535 to be output to assembler.
1536 Set first_global_object_name and weak_global_object_name as appropriate. */
1538 void
1539 notice_global_symbol (tree decl)
1541 const char **type = &first_global_object_name;
1543 if (first_global_object_name
1544 || !TREE_PUBLIC (decl)
1545 || DECL_EXTERNAL (decl)
1546 || !DECL_NAME (decl)
1547 || (TREE_CODE (decl) != FUNCTION_DECL
1548 && (TREE_CODE (decl) != VAR_DECL
1549 || (DECL_COMMON (decl)
1550 && (DECL_INITIAL (decl) == 0
1551 || DECL_INITIAL (decl) == error_mark_node))))
1552 || !MEM_P (DECL_RTL (decl)))
1553 return;
1555 /* We win when global object is found, but it is useful to know about weak
1556 symbol as well so we can produce nicer unique names. */
1557 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl) || flag_shlib)
1558 type = &weak_global_object_name;
1560 if (!*type)
1562 const char *p;
1563 const char *name;
1564 rtx decl_rtl = DECL_RTL (decl);
1566 p = targetm.strip_name_encoding (XSTR (XEXP (decl_rtl, 0), 0));
1567 name = ggc_strdup (p);
1569 *type = name;
1573 /* If not using flag_reorder_blocks_and_partition, decide early whether the
1574 current function goes into the cold section, so that targets can use
1575 current_function_section during RTL expansion. DECL describes the
1576 function. */
1578 void
1579 decide_function_section (tree decl)
1581 first_function_block_is_cold = false;
1583 if (flag_reorder_blocks_and_partition)
1584 /* We will decide in assemble_start_function. */
1585 return;
1587 if (DECL_SECTION_NAME (decl))
1589 struct cgraph_node *node = cgraph_get_node (current_function_decl);
1590 /* Calls to function_section rely on first_function_block_is_cold
1591 being accurate. */
1592 first_function_block_is_cold = (node
1593 && node->frequency
1594 == NODE_FREQUENCY_UNLIKELY_EXECUTED);
1597 in_cold_section_p = first_function_block_is_cold;
1600 /* Output assembler code for the constant pool of a function and associated
1601 with defining the name of the function. DECL describes the function.
1602 NAME is the function's name. For the constant pool, we use the current
1603 constant pool data. */
1605 void
1606 assemble_start_function (tree decl, const char *fnname)
1608 int align;
1609 char tmp_label[100];
1610 bool hot_label_written = false;
1612 if (flag_reorder_blocks_and_partition)
1614 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTB", const_labelno);
1615 crtl->subsections.hot_section_label = ggc_strdup (tmp_label);
1616 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDB", const_labelno);
1617 crtl->subsections.cold_section_label = ggc_strdup (tmp_label);
1618 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTE", const_labelno);
1619 crtl->subsections.hot_section_end_label = ggc_strdup (tmp_label);
1620 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDE", const_labelno);
1621 crtl->subsections.cold_section_end_label = ggc_strdup (tmp_label);
1622 const_labelno++;
1624 else
1626 crtl->subsections.hot_section_label = NULL;
1627 crtl->subsections.cold_section_label = NULL;
1628 crtl->subsections.hot_section_end_label = NULL;
1629 crtl->subsections.cold_section_end_label = NULL;
1632 /* The following code does not need preprocessing in the assembler. */
1634 app_disable ();
1636 if (CONSTANT_POOL_BEFORE_FUNCTION)
1637 output_constant_pool (fnname, decl);
1639 /* Make sure the not and cold text (code) sections are properly
1640 aligned. This is necessary here in the case where the function
1641 has both hot and cold sections, because we don't want to re-set
1642 the alignment when the section switch happens mid-function. */
1644 if (flag_reorder_blocks_and_partition)
1646 first_function_block_is_cold = false;
1648 switch_to_section (unlikely_text_section ());
1649 assemble_align (DECL_ALIGN (decl));
1650 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_label);
1652 /* When the function starts with a cold section, we need to explicitly
1653 align the hot section and write out the hot section label.
1654 But if the current function is a thunk, we do not have a CFG. */
1655 if (!cfun->is_thunk
1656 && BB_PARTITION (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) == BB_COLD_PARTITION)
1658 switch_to_section (text_section);
1659 assemble_align (DECL_ALIGN (decl));
1660 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1661 hot_label_written = true;
1662 first_function_block_is_cold = true;
1664 in_cold_section_p = first_function_block_is_cold;
1668 /* Switch to the correct text section for the start of the function. */
1670 switch_to_section (function_section (decl));
1671 if (flag_reorder_blocks_and_partition
1672 && !hot_label_written)
1673 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1675 /* Tell assembler to move to target machine's alignment for functions. */
1676 align = floor_log2 (DECL_ALIGN (decl) / BITS_PER_UNIT);
1677 if (align > 0)
1679 ASM_OUTPUT_ALIGN (asm_out_file, align);
1682 /* Handle a user-specified function alignment.
1683 Note that we still need to align to DECL_ALIGN, as above,
1684 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1685 if (! DECL_USER_ALIGN (decl)
1686 && align_functions_log > align
1687 && optimize_function_for_speed_p (cfun))
1689 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1690 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1691 align_functions_log, align_functions - 1);
1692 #else
1693 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1694 #endif
1697 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1698 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1699 #endif
1701 if (!DECL_IGNORED_P (decl))
1702 (*debug_hooks->begin_function) (decl);
1704 /* Make function name accessible from other files, if appropriate. */
1706 if (TREE_PUBLIC (decl))
1708 notice_global_symbol (decl);
1710 globalize_decl (decl);
1712 maybe_assemble_visibility (decl);
1715 if (DECL_PRESERVE_P (decl))
1716 targetm.asm_out.mark_decl_preserved (fnname);
1718 /* Do any machine/system dependent processing of the function name. */
1719 #ifdef ASM_DECLARE_FUNCTION_NAME
1720 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1721 #else
1722 /* Standard thing is just output label for the function. */
1723 ASM_OUTPUT_FUNCTION_LABEL (asm_out_file, fnname, current_function_decl);
1724 #endif /* ASM_DECLARE_FUNCTION_NAME */
1726 if (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (decl)))
1727 saw_no_split_stack = true;
1730 /* Output assembler code associated with defining the size of the
1731 function. DECL describes the function. NAME is the function's name. */
1733 void
1734 assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED)
1736 #ifdef ASM_DECLARE_FUNCTION_SIZE
1737 /* We could have switched section in the middle of the function. */
1738 if (flag_reorder_blocks_and_partition)
1739 switch_to_section (function_section (decl));
1740 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1741 #endif
1742 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1744 output_constant_pool (fnname, decl);
1745 switch_to_section (function_section (decl)); /* need to switch back */
1747 /* Output labels for end of hot/cold text sections (to be used by
1748 debug info.) */
1749 if (flag_reorder_blocks_and_partition)
1751 section *save_text_section;
1753 save_text_section = in_section;
1754 switch_to_section (unlikely_text_section ());
1755 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label);
1756 if (first_function_block_is_cold)
1757 switch_to_section (text_section);
1758 else
1759 switch_to_section (function_section (decl));
1760 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label);
1761 switch_to_section (save_text_section);
1765 /* Assemble code to leave SIZE bytes of zeros. */
1767 void
1768 assemble_zeros (unsigned HOST_WIDE_INT size)
1770 /* Do no output if -fsyntax-only. */
1771 if (flag_syntax_only)
1772 return;
1774 #ifdef ASM_NO_SKIP_IN_TEXT
1775 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1776 so we must output 0s explicitly in the text section. */
1777 if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0)
1779 unsigned HOST_WIDE_INT i;
1780 for (i = 0; i < size; i++)
1781 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1783 else
1784 #endif
1785 if (size > 0)
1786 ASM_OUTPUT_SKIP (asm_out_file, size);
1789 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1791 void
1792 assemble_align (int align)
1794 if (align > BITS_PER_UNIT)
1796 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1800 /* Assemble a string constant with the specified C string as contents. */
1802 void
1803 assemble_string (const char *p, int size)
1805 int pos = 0;
1806 int maximum = 2000;
1808 /* If the string is very long, split it up. */
1810 while (pos < size)
1812 int thissize = size - pos;
1813 if (thissize > maximum)
1814 thissize = maximum;
1816 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1818 pos += thissize;
1819 p += thissize;
1824 /* A noswitch_section_callback for lcomm_section. */
1826 static bool
1827 emit_local (tree decl ATTRIBUTE_UNUSED,
1828 const char *name ATTRIBUTE_UNUSED,
1829 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1830 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1832 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1833 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name,
1834 size, DECL_ALIGN (decl));
1835 return true;
1836 #elif defined ASM_OUTPUT_ALIGNED_LOCAL
1837 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, DECL_ALIGN (decl));
1838 return true;
1839 #else
1840 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1841 return false;
1842 #endif
1845 /* A noswitch_section_callback for bss_noswitch_section. */
1847 #if defined ASM_OUTPUT_ALIGNED_BSS
1848 static bool
1849 emit_bss (tree decl ATTRIBUTE_UNUSED,
1850 const char *name ATTRIBUTE_UNUSED,
1851 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1852 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1854 #if defined ASM_OUTPUT_ALIGNED_BSS
1855 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size,
1856 get_variable_align (decl));
1857 return true;
1858 #endif
1860 #endif
1862 /* A noswitch_section_callback for comm_section. */
1864 static bool
1865 emit_common (tree decl ATTRIBUTE_UNUSED,
1866 const char *name ATTRIBUTE_UNUSED,
1867 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1868 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1870 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1871 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name,
1872 size, get_variable_align (decl));
1873 return true;
1874 #elif defined ASM_OUTPUT_ALIGNED_COMMON
1875 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size,
1876 get_variable_align (decl));
1877 return true;
1878 #else
1879 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
1880 return false;
1881 #endif
1884 /* A noswitch_section_callback for tls_comm_section. */
1886 static bool
1887 emit_tls_common (tree decl ATTRIBUTE_UNUSED,
1888 const char *name ATTRIBUTE_UNUSED,
1889 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1890 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1892 #ifdef ASM_OUTPUT_TLS_COMMON
1893 ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size);
1894 return true;
1895 #else
1896 sorry ("thread-local COMMON data not implemented");
1897 return true;
1898 #endif
1901 /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT.
1902 NAME is the name of DECL's SYMBOL_REF. */
1904 static void
1905 assemble_noswitch_variable (tree decl, const char *name, section *sect,
1906 unsigned int align)
1908 unsigned HOST_WIDE_INT size, rounded;
1910 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
1911 rounded = size;
1913 if ((flag_sanitize & SANITIZE_ADDRESS) && asan_protect_global (decl))
1914 size += asan_red_zone_size (size);
1916 /* Don't allocate zero bytes of common,
1917 since that means "undefined external" in the linker. */
1918 if (size == 0)
1919 rounded = 1;
1921 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1922 so that each uninitialized object starts on such a boundary. */
1923 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
1924 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1925 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1927 if (!sect->noswitch.callback (decl, name, size, rounded)
1928 && (unsigned HOST_WIDE_INT) (align / BITS_PER_UNIT) > rounded)
1929 error ("requested alignment for %q+D is greater than "
1930 "implemented alignment of %wu", decl, rounded);
1933 /* A subroutine of assemble_variable. Output the label and contents of
1934 DECL, whose address is a SYMBOL_REF with name NAME. DONT_OUTPUT_DATA
1935 is as for assemble_variable. */
1937 static void
1938 assemble_variable_contents (tree decl, const char *name,
1939 bool dont_output_data)
1941 /* Do any machine/system dependent processing of the object. */
1942 #ifdef ASM_DECLARE_OBJECT_NAME
1943 last_assemble_variable_decl = decl;
1944 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
1945 #else
1946 /* Standard thing is just output label for the object. */
1947 ASM_OUTPUT_LABEL (asm_out_file, name);
1948 #endif /* ASM_DECLARE_OBJECT_NAME */
1950 if (!dont_output_data)
1952 if (DECL_INITIAL (decl)
1953 && DECL_INITIAL (decl) != error_mark_node
1954 && !initializer_zerop (DECL_INITIAL (decl)))
1955 /* Output the actual data. */
1956 output_constant (DECL_INITIAL (decl),
1957 tree_to_uhwi (DECL_SIZE_UNIT (decl)),
1958 get_variable_align (decl));
1959 else
1960 /* Leave space for it. */
1961 assemble_zeros (tree_to_uhwi (DECL_SIZE_UNIT (decl)));
1965 /* Assemble everything that is needed for a variable or function declaration.
1966 Not used for automatic variables, and not used for function definitions.
1967 Should not be called for variables of incomplete structure type.
1969 TOP_LEVEL is nonzero if this variable has file scope.
1970 AT_END is nonzero if this is the special handling, at end of compilation,
1971 to define things that have had only tentative definitions.
1972 DONT_OUTPUT_DATA if nonzero means don't actually output the
1973 initial value (that will be done by the caller). */
1975 void
1976 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
1977 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
1979 const char *name;
1980 rtx decl_rtl, symbol;
1981 section *sect;
1982 unsigned int align;
1983 bool asan_protected = false;
1985 /* This function is supposed to handle VARIABLES. Ensure we have one. */
1986 gcc_assert (TREE_CODE (decl) == VAR_DECL);
1988 /* Emulated TLS had better not get this far. */
1989 gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl));
1991 last_assemble_variable_decl = 0;
1993 /* Normally no need to say anything here for external references,
1994 since assemble_external is called by the language-specific code
1995 when a declaration is first seen. */
1997 if (DECL_EXTERNAL (decl))
1998 return;
2000 /* Do nothing for global register variables. */
2001 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
2003 TREE_ASM_WRITTEN (decl) = 1;
2004 return;
2007 /* If type was incomplete when the variable was declared,
2008 see if it is complete now. */
2010 if (DECL_SIZE (decl) == 0)
2011 layout_decl (decl, 0);
2013 /* Still incomplete => don't allocate it; treat the tentative defn
2014 (which is what it must have been) as an `extern' reference. */
2016 if (!dont_output_data && DECL_SIZE (decl) == 0)
2018 error ("storage size of %q+D isn%'t known", decl);
2019 TREE_ASM_WRITTEN (decl) = 1;
2020 return;
2023 /* The first declaration of a variable that comes through this function
2024 decides whether it is global (in C, has external linkage)
2025 or local (in C, has internal linkage). So do nothing more
2026 if this function has already run. */
2028 if (TREE_ASM_WRITTEN (decl))
2029 return;
2031 /* Make sure targetm.encode_section_info is invoked before we set
2032 ASM_WRITTEN. */
2033 decl_rtl = DECL_RTL (decl);
2035 TREE_ASM_WRITTEN (decl) = 1;
2037 /* Do no output if -fsyntax-only. */
2038 if (flag_syntax_only)
2039 return;
2041 if (! dont_output_data
2042 && ! valid_constant_size_p (DECL_SIZE_UNIT (decl)))
2044 error ("size of variable %q+D is too large", decl);
2045 return;
2048 gcc_assert (MEM_P (decl_rtl));
2049 gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF);
2050 symbol = XEXP (decl_rtl, 0);
2052 /* If this symbol belongs to the tree constant pool, output the constant
2053 if it hasn't already been written. */
2054 if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
2056 tree decl = SYMBOL_REF_DECL (symbol);
2057 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
2058 output_constant_def_contents (symbol);
2059 return;
2062 app_disable ();
2064 name = XSTR (symbol, 0);
2065 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
2066 notice_global_symbol (decl);
2068 /* Compute the alignment of this data. */
2070 align_variable (decl, dont_output_data);
2072 if ((flag_sanitize & SANITIZE_ADDRESS)
2073 && asan_protect_global (decl))
2075 asan_protected = true;
2076 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
2077 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
2080 set_mem_align (decl_rtl, DECL_ALIGN (decl));
2082 align = get_variable_align (decl);
2084 if (TREE_PUBLIC (decl))
2085 maybe_assemble_visibility (decl);
2087 if (DECL_PRESERVE_P (decl))
2088 targetm.asm_out.mark_decl_preserved (name);
2090 /* First make the assembler name(s) global if appropriate. */
2091 sect = get_variable_section (decl, false);
2092 if (TREE_PUBLIC (decl)
2093 && (sect->common.flags & SECTION_COMMON) == 0)
2094 globalize_decl (decl);
2096 /* Output any data that we will need to use the address of. */
2097 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
2098 output_addressed_constants (DECL_INITIAL (decl));
2100 /* dbxout.c needs to know this. */
2101 if (sect && (sect->common.flags & SECTION_CODE) != 0)
2102 DECL_IN_TEXT_SECTION (decl) = 1;
2104 /* If the decl is part of an object_block, make sure that the decl
2105 has been positioned within its block, but do not write out its
2106 definition yet. output_object_blocks will do that later. */
2107 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
2109 gcc_assert (!dont_output_data);
2110 place_block_symbol (symbol);
2112 else if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
2113 assemble_noswitch_variable (decl, name, sect, align);
2114 else
2116 /* The following bit of code ensures that vtable_map
2117 variables are not only in the comdat section, but that
2118 each variable has its own unique comdat name. If this
2119 code is removed, the variables end up in the same section
2120 with a single comdat name.
2122 FIXME: resolve_unique_section needs to deal better with
2123 decls with both DECL_SECTION_NAME and DECL_ONE_ONLY. Once
2124 that is fixed, this if-else statement can be replaced with
2125 a single call to "switch_to_section (sect)". */
2126 if (sect->named.name
2127 && (strcmp (sect->named.name, ".vtable_map_vars") == 0))
2129 #if defined (OBJECT_FORMAT_ELF)
2130 targetm.asm_out.named_section (sect->named.name,
2131 sect->named.common.flags
2132 | SECTION_LINKONCE,
2133 DECL_NAME (decl));
2134 in_section = sect;
2135 #else
2136 switch_to_section (sect);
2137 #endif
2139 else
2140 switch_to_section (sect);
2141 if (align > BITS_PER_UNIT)
2142 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2143 assemble_variable_contents (decl, name, dont_output_data);
2144 if (asan_protected)
2146 unsigned HOST_WIDE_INT int size
2147 = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2148 assemble_zeros (asan_red_zone_size (size));
2154 /* Given a function declaration (FN_DECL), this function assembles the
2155 function into the .preinit_array section. */
2157 void
2158 assemble_vtv_preinit_initializer (tree fn_decl)
2160 section *sect;
2161 unsigned flags = SECTION_WRITE;
2162 rtx symbol = XEXP (DECL_RTL (fn_decl), 0);
2164 flags |= SECTION_NOTYPE;
2165 sect = get_section (".preinit_array", flags, fn_decl);
2166 switch_to_section (sect);
2167 assemble_addr_to_section (symbol, sect);
2170 /* Return 1 if type TYPE contains any pointers. */
2172 static int
2173 contains_pointers_p (tree type)
2175 switch (TREE_CODE (type))
2177 case POINTER_TYPE:
2178 case REFERENCE_TYPE:
2179 /* I'm not sure whether OFFSET_TYPE needs this treatment,
2180 so I'll play safe and return 1. */
2181 case OFFSET_TYPE:
2182 return 1;
2184 case RECORD_TYPE:
2185 case UNION_TYPE:
2186 case QUAL_UNION_TYPE:
2188 tree fields;
2189 /* For a type that has fields, see if the fields have pointers. */
2190 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2191 if (TREE_CODE (fields) == FIELD_DECL
2192 && contains_pointers_p (TREE_TYPE (fields)))
2193 return 1;
2194 return 0;
2197 case ARRAY_TYPE:
2198 /* An array type contains pointers if its element type does. */
2199 return contains_pointers_p (TREE_TYPE (type));
2201 default:
2202 return 0;
2206 /* We delay assemble_external processing until
2207 the compilation unit is finalized. This is the best we can do for
2208 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2209 it all the way to final. See PR 17982 for further discussion. */
2210 static GTY(()) tree pending_assemble_externals;
2212 #ifdef ASM_OUTPUT_EXTERNAL
2213 /* Some targets delay some output to final using TARGET_ASM_FILE_END.
2214 As a result, assemble_external can be called after the list of externals
2215 is processed and the pointer set destroyed. */
2216 static bool pending_assemble_externals_processed;
2218 /* Avoid O(external_decls**2) lookups in the pending_assemble_externals
2219 TREE_LIST in assemble_external. */
2220 static struct pointer_set_t *pending_assemble_externals_set;
2222 /* True if DECL is a function decl for which no out-of-line copy exists.
2223 It is assumed that DECL's assembler name has been set. */
2225 static bool
2226 incorporeal_function_p (tree decl)
2228 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
2230 const char *name;
2232 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2233 && (DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA
2234 || DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA_WITH_ALIGN))
2235 return true;
2237 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2238 /* Atomic or sync builtins which have survived this far will be
2239 resolved externally and therefore are not incorporeal. */
2240 if (strncmp (name, "__builtin_", 10) == 0)
2241 return true;
2243 return false;
2246 /* Actually do the tests to determine if this is necessary, and invoke
2247 ASM_OUTPUT_EXTERNAL. */
2248 static void
2249 assemble_external_real (tree decl)
2251 rtx rtl = DECL_RTL (decl);
2253 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2254 && !SYMBOL_REF_USED (XEXP (rtl, 0))
2255 && !incorporeal_function_p (decl))
2257 /* Some systems do require some output. */
2258 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2259 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2262 #endif
2264 void
2265 process_pending_assemble_externals (void)
2267 #ifdef ASM_OUTPUT_EXTERNAL
2268 tree list;
2269 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2270 assemble_external_real (TREE_VALUE (list));
2272 pending_assemble_externals = 0;
2273 pending_assemble_externals_processed = true;
2274 pointer_set_destroy (pending_assemble_externals_set);
2275 #endif
2278 /* This TREE_LIST contains any weak symbol declarations waiting
2279 to be emitted. */
2280 static GTY(()) tree weak_decls;
2282 /* Output something to declare an external symbol to the assembler,
2283 and qualifiers such as weakness. (Most assemblers don't need
2284 extern declaration, so we normally output nothing.) Do nothing if
2285 DECL is not external. */
2287 void
2288 assemble_external (tree decl ATTRIBUTE_UNUSED)
2290 /* Make sure that the ASM_OUT_FILE is open.
2291 If it's not, we should not be calling this function. */
2292 gcc_assert (asm_out_file);
2294 /* In a perfect world, the following condition would be true.
2295 Sadly, the Java and Go front ends emit assembly *from the front end*,
2296 bypassing the call graph. See PR52739. Fix before GCC 4.8. */
2297 #if 0
2298 /* This function should only be called if we are expanding, or have
2299 expanded, to RTL.
2300 Ideally, only final.c would be calling this function, but it is
2301 not clear whether that would break things somehow. See PR 17982
2302 for further discussion. */
2303 gcc_assert (cgraph_state == CGRAPH_STATE_EXPANSION
2304 || cgraph_state == CGRAPH_STATE_FINISHED);
2305 #endif
2307 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2308 return;
2310 /* We want to output annotation for weak and external symbols at
2311 very last to check if they are references or not. */
2313 if (TARGET_SUPPORTS_WEAK
2314 && DECL_WEAK (decl)
2315 /* TREE_STATIC is a weird and abused creature which is not
2316 generally the right test for whether an entity has been
2317 locally emitted, inlined or otherwise not-really-extern, but
2318 for declarations that can be weak, it happens to be
2319 match. */
2320 && !TREE_STATIC (decl)
2321 && lookup_attribute ("weak", DECL_ATTRIBUTES (decl))
2322 && value_member (decl, weak_decls) == NULL_TREE)
2323 weak_decls = tree_cons (NULL, decl, weak_decls);
2325 #ifdef ASM_OUTPUT_EXTERNAL
2326 if (pending_assemble_externals_processed)
2328 assemble_external_real (decl);
2329 return;
2332 if (! pointer_set_insert (pending_assemble_externals_set, decl))
2333 pending_assemble_externals = tree_cons (NULL, decl,
2334 pending_assemble_externals);
2335 #endif
2338 /* Similar, for calling a library function FUN. */
2340 void
2341 assemble_external_libcall (rtx fun)
2343 /* Declare library function name external when first used, if nec. */
2344 if (! SYMBOL_REF_USED (fun))
2346 SYMBOL_REF_USED (fun) = 1;
2347 targetm.asm_out.external_libcall (fun);
2351 /* Assemble a label named NAME. */
2353 void
2354 assemble_label (FILE *file, const char *name)
2356 ASM_OUTPUT_LABEL (file, name);
2359 /* Set the symbol_referenced flag for ID. */
2360 void
2361 mark_referenced (tree id)
2363 TREE_SYMBOL_REFERENCED (id) = 1;
2366 /* Set the symbol_referenced flag for DECL and notify callgraph. */
2367 void
2368 mark_decl_referenced (tree decl)
2370 if (TREE_CODE (decl) == FUNCTION_DECL)
2372 /* Extern inline functions don't become needed when referenced.
2373 If we know a method will be emitted in other TU and no new
2374 functions can be marked reachable, just use the external
2375 definition. */
2376 struct cgraph_node *node = cgraph_get_create_node (decl);
2377 if (!DECL_EXTERNAL (decl)
2378 && !node->definition)
2379 cgraph_mark_force_output_node (node);
2381 else if (TREE_CODE (decl) == VAR_DECL)
2383 varpool_node *node = varpool_node_for_decl (decl);
2384 /* C++ frontend use mark_decl_references to force COMDAT variables
2385 to be output that might appear dead otherwise. */
2386 node->force_output = true;
2388 /* else do nothing - we can get various sorts of CST nodes here,
2389 which do not need to be marked. */
2393 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS
2394 until we find an identifier that is not itself a transparent alias.
2395 Modify the alias passed to it by reference (and all aliases on the
2396 way to the ultimate target), such that they do not have to be
2397 followed again, and return the ultimate target of the alias
2398 chain. */
2400 static inline tree
2401 ultimate_transparent_alias_target (tree *alias)
2403 tree target = *alias;
2405 if (IDENTIFIER_TRANSPARENT_ALIAS (target))
2407 gcc_assert (TREE_CHAIN (target));
2408 target = ultimate_transparent_alias_target (&TREE_CHAIN (target));
2409 gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target)
2410 && ! TREE_CHAIN (target));
2411 *alias = target;
2414 return target;
2417 /* Output to FILE (an assembly file) a reference to NAME. If NAME
2418 starts with a *, the rest of NAME is output verbatim. Otherwise
2419 NAME is transformed in a target-specific way (usually by the
2420 addition of an underscore). */
2422 void
2423 assemble_name_raw (FILE *file, const char *name)
2425 if (name[0] == '*')
2426 fputs (&name[1], file);
2427 else
2428 ASM_OUTPUT_LABELREF (file, name);
2431 /* Like assemble_name_raw, but should be used when NAME might refer to
2432 an entity that is also represented as a tree (like a function or
2433 variable). If NAME does refer to such an entity, that entity will
2434 be marked as referenced. */
2436 void
2437 assemble_name (FILE *file, const char *name)
2439 const char *real_name;
2440 tree id;
2442 real_name = targetm.strip_name_encoding (name);
2444 id = maybe_get_identifier (real_name);
2445 if (id)
2447 tree id_orig = id;
2449 mark_referenced (id);
2450 ultimate_transparent_alias_target (&id);
2451 if (id != id_orig)
2452 name = IDENTIFIER_POINTER (id);
2453 gcc_assert (! TREE_CHAIN (id));
2456 assemble_name_raw (file, name);
2459 /* Allocate SIZE bytes writable static space with a gensym name
2460 and return an RTX to refer to its address. */
2463 assemble_static_space (unsigned HOST_WIDE_INT size)
2465 char name[12];
2466 const char *namestring;
2467 rtx x;
2469 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2470 ++const_labelno;
2471 namestring = ggc_strdup (name);
2473 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2474 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2476 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2477 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2478 BIGGEST_ALIGNMENT);
2479 #else
2480 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2481 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2482 #else
2484 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2485 so that each uninitialized object starts on such a boundary. */
2486 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2487 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2488 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2489 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2490 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2491 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2493 #endif
2494 #endif
2495 return x;
2498 /* Assemble the static constant template for function entry trampolines.
2499 This is done at most once per compilation.
2500 Returns an RTX for the address of the template. */
2502 static GTY(()) rtx initial_trampoline;
2505 assemble_trampoline_template (void)
2507 char label[256];
2508 const char *name;
2509 int align;
2510 rtx symbol;
2512 gcc_assert (targetm.asm_out.trampoline_template != NULL);
2514 if (initial_trampoline)
2515 return initial_trampoline;
2517 /* By default, put trampoline templates in read-only data section. */
2519 #ifdef TRAMPOLINE_SECTION
2520 switch_to_section (TRAMPOLINE_SECTION);
2521 #else
2522 switch_to_section (readonly_data_section);
2523 #endif
2525 /* Write the assembler code to define one. */
2526 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2527 if (align > 0)
2528 ASM_OUTPUT_ALIGN (asm_out_file, align);
2530 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2531 targetm.asm_out.trampoline_template (asm_out_file);
2533 /* Record the rtl to refer to it. */
2534 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2535 name = ggc_strdup (label);
2536 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2537 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2539 initial_trampoline = gen_const_mem (BLKmode, symbol);
2540 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2541 set_mem_size (initial_trampoline, TRAMPOLINE_SIZE);
2543 return initial_trampoline;
2546 /* A and B are either alignments or offsets. Return the minimum alignment
2547 that may be assumed after adding the two together. */
2549 static inline unsigned
2550 min_align (unsigned int a, unsigned int b)
2552 return (a | b) & -(a | b);
2555 /* Return the assembler directive for creating a given kind of integer
2556 object. SIZE is the number of bytes in the object and ALIGNED_P
2557 indicates whether it is known to be aligned. Return NULL if the
2558 assembly dialect has no such directive.
2560 The returned string should be printed at the start of a new line and
2561 be followed immediately by the object's initial value. */
2563 const char *
2564 integer_asm_op (int size, int aligned_p)
2566 struct asm_int_op *ops;
2568 if (aligned_p)
2569 ops = &targetm.asm_out.aligned_op;
2570 else
2571 ops = &targetm.asm_out.unaligned_op;
2573 switch (size)
2575 case 1:
2576 return targetm.asm_out.byte_op;
2577 case 2:
2578 return ops->hi;
2579 case 4:
2580 return ops->si;
2581 case 8:
2582 return ops->di;
2583 case 16:
2584 return ops->ti;
2585 default:
2586 return NULL;
2590 /* Use directive OP to assemble an integer object X. Print OP at the
2591 start of the line, followed immediately by the value of X. */
2593 void
2594 assemble_integer_with_op (const char *op, rtx x)
2596 fputs (op, asm_out_file);
2597 output_addr_const (asm_out_file, x);
2598 fputc ('\n', asm_out_file);
2601 /* The default implementation of the asm_out.integer target hook. */
2603 bool
2604 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2605 unsigned int size ATTRIBUTE_UNUSED,
2606 int aligned_p ATTRIBUTE_UNUSED)
2608 const char *op = integer_asm_op (size, aligned_p);
2609 /* Avoid GAS bugs for large values. Specifically negative values whose
2610 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2611 if (size > UNITS_PER_WORD && size > POINTER_SIZE / BITS_PER_UNIT)
2612 return false;
2613 return op && (assemble_integer_with_op (op, x), true);
2616 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2617 the alignment of the integer in bits. Return 1 if we were able to output
2618 the constant, otherwise 0. We must be able to output the constant,
2619 if FORCE is nonzero. */
2621 bool
2622 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2624 int aligned_p;
2626 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2628 /* See if the target hook can handle this kind of object. */
2629 if (targetm.asm_out.integer (x, size, aligned_p))
2630 return true;
2632 /* If the object is a multi-byte one, try splitting it up. Split
2633 it into words it if is multi-word, otherwise split it into bytes. */
2634 if (size > 1)
2636 enum machine_mode omode, imode;
2637 unsigned int subalign;
2638 unsigned int subsize, i;
2639 enum mode_class mclass;
2641 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2642 subalign = MIN (align, subsize * BITS_PER_UNIT);
2643 if (GET_CODE (x) == CONST_FIXED)
2644 mclass = GET_MODE_CLASS (GET_MODE (x));
2645 else
2646 mclass = MODE_INT;
2648 omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0);
2649 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0);
2651 for (i = 0; i < size; i += subsize)
2653 rtx partial = simplify_subreg (omode, x, imode, i);
2654 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2655 break;
2657 if (i == size)
2658 return true;
2660 /* If we've printed some of it, but not all of it, there's no going
2661 back now. */
2662 gcc_assert (!i);
2665 gcc_assert (!force);
2667 return false;
2670 void
2671 assemble_real (REAL_VALUE_TYPE d, enum machine_mode mode, unsigned int align)
2673 long data[4] = {0, 0, 0, 0};
2674 int i;
2675 int bitsize, nelts, nunits, units_per;
2677 /* This is hairy. We have a quantity of known size. real_to_target
2678 will put it into an array of *host* longs, 32 bits per element
2679 (even if long is more than 32 bits). We need to determine the
2680 number of array elements that are occupied (nelts) and the number
2681 of *target* min-addressable units that will be occupied in the
2682 object file (nunits). We cannot assume that 32 divides the
2683 mode's bitsize (size * BITS_PER_UNIT) evenly.
2685 size * BITS_PER_UNIT is used here to make sure that padding bits
2686 (which might appear at either end of the value; real_to_target
2687 will include the padding bits in its output array) are included. */
2689 nunits = GET_MODE_SIZE (mode);
2690 bitsize = nunits * BITS_PER_UNIT;
2691 nelts = CEIL (bitsize, 32);
2692 units_per = 32 / BITS_PER_UNIT;
2694 real_to_target (data, &d, mode);
2696 /* Put out the first word with the specified alignment. */
2697 assemble_integer (GEN_INT (data[0]), MIN (nunits, units_per), align, 1);
2698 nunits -= units_per;
2700 /* Subsequent words need only 32-bit alignment. */
2701 align = min_align (align, 32);
2703 for (i = 1; i < nelts; i++)
2705 assemble_integer (GEN_INT (data[i]), MIN (nunits, units_per), align, 1);
2706 nunits -= units_per;
2710 /* Given an expression EXP with a constant value,
2711 reduce it to the sum of an assembler symbol and an integer.
2712 Store them both in the structure *VALUE.
2713 EXP must be reducible. */
2715 struct addr_const {
2716 rtx base;
2717 HOST_WIDE_INT offset;
2720 static void
2721 decode_addr_const (tree exp, struct addr_const *value)
2723 tree target = TREE_OPERAND (exp, 0);
2724 int offset = 0;
2725 rtx x;
2727 while (1)
2729 if (TREE_CODE (target) == COMPONENT_REF
2730 && tree_fits_shwi_p (byte_position (TREE_OPERAND (target, 1))))
2732 offset += int_byte_position (TREE_OPERAND (target, 1));
2733 target = TREE_OPERAND (target, 0);
2735 else if (TREE_CODE (target) == ARRAY_REF
2736 || TREE_CODE (target) == ARRAY_RANGE_REF)
2738 offset += (tree_to_uhwi (TYPE_SIZE_UNIT (TREE_TYPE (target)))
2739 * tree_to_shwi (TREE_OPERAND (target, 1)));
2740 target = TREE_OPERAND (target, 0);
2742 else if (TREE_CODE (target) == MEM_REF
2743 && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR)
2745 offset += mem_ref_offset (target).to_short_addr ();
2746 target = TREE_OPERAND (TREE_OPERAND (target, 0), 0);
2748 else if (TREE_CODE (target) == INDIRECT_REF
2749 && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR
2750 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0))
2751 == ADDR_EXPR)
2752 target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0);
2753 else
2754 break;
2757 switch (TREE_CODE (target))
2759 case VAR_DECL:
2760 case FUNCTION_DECL:
2761 x = DECL_RTL (target);
2762 break;
2764 case LABEL_DECL:
2765 x = gen_rtx_MEM (FUNCTION_MODE,
2766 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2767 break;
2769 case REAL_CST:
2770 case FIXED_CST:
2771 case STRING_CST:
2772 case COMPLEX_CST:
2773 case CONSTRUCTOR:
2774 case INTEGER_CST:
2775 x = output_constant_def (target, 1);
2776 break;
2778 default:
2779 gcc_unreachable ();
2782 gcc_assert (MEM_P (x));
2783 x = XEXP (x, 0);
2785 value->base = x;
2786 value->offset = offset;
2790 static GTY((param_is (struct constant_descriptor_tree)))
2791 htab_t const_desc_htab;
2793 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2795 /* Constant pool accessor function. */
2797 htab_t
2798 constant_pool_htab (void)
2800 return const_desc_htab;
2803 /* Compute a hash code for a constant expression. */
2805 static hashval_t
2806 const_desc_hash (const void *ptr)
2808 return ((const struct constant_descriptor_tree *)ptr)->hash;
2811 static hashval_t
2812 const_hash_1 (const tree exp)
2814 const char *p;
2815 hashval_t hi;
2816 int len, i;
2817 enum tree_code code = TREE_CODE (exp);
2819 /* Either set P and LEN to the address and len of something to hash and
2820 exit the switch or return a value. */
2822 switch (code)
2824 case INTEGER_CST:
2825 p = (char *) &TREE_INT_CST_ELT (exp, 0);
2826 len = TREE_INT_CST_NUNITS (exp) * sizeof (HOST_WIDE_INT);
2827 break;
2829 case REAL_CST:
2830 return real_hash (TREE_REAL_CST_PTR (exp));
2832 case FIXED_CST:
2833 return fixed_hash (TREE_FIXED_CST_PTR (exp));
2835 case STRING_CST:
2836 p = TREE_STRING_POINTER (exp);
2837 len = TREE_STRING_LENGTH (exp);
2838 break;
2840 case COMPLEX_CST:
2841 return (const_hash_1 (TREE_REALPART (exp)) * 5
2842 + const_hash_1 (TREE_IMAGPART (exp)));
2844 case VECTOR_CST:
2846 unsigned i;
2848 hi = 7 + VECTOR_CST_NELTS (exp);
2850 for (i = 0; i < VECTOR_CST_NELTS (exp); ++i)
2851 hi = hi * 563 + const_hash_1 (VECTOR_CST_ELT (exp, i));
2853 return hi;
2856 case CONSTRUCTOR:
2858 unsigned HOST_WIDE_INT idx;
2859 tree value;
2861 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2863 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
2864 if (value)
2865 hi = hi * 603 + const_hash_1 (value);
2867 return hi;
2870 case ADDR_EXPR:
2871 case FDESC_EXPR:
2873 struct addr_const value;
2875 decode_addr_const (exp, &value);
2876 switch (GET_CODE (value.base))
2878 case SYMBOL_REF:
2879 /* Don't hash the address of the SYMBOL_REF;
2880 only use the offset and the symbol name. */
2881 hi = value.offset;
2882 p = XSTR (value.base, 0);
2883 for (i = 0; p[i] != 0; i++)
2884 hi = ((hi * 613) + (unsigned) (p[i]));
2885 break;
2887 case LABEL_REF:
2888 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13;
2889 break;
2891 default:
2892 gcc_unreachable ();
2895 return hi;
2897 case PLUS_EXPR:
2898 case POINTER_PLUS_EXPR:
2899 case MINUS_EXPR:
2900 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2901 + const_hash_1 (TREE_OPERAND (exp, 1)));
2903 CASE_CONVERT:
2904 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
2906 default:
2907 /* A language specific constant. Just hash the code. */
2908 return code;
2911 /* Compute hashing function. */
2912 hi = len;
2913 for (i = 0; i < len; i++)
2914 hi = ((hi * 613) + (unsigned) (p[i]));
2916 return hi;
2919 /* Wrapper of compare_constant, for the htab interface. */
2920 static int
2921 const_desc_eq (const void *p1, const void *p2)
2923 const struct constant_descriptor_tree *const c1
2924 = (const struct constant_descriptor_tree *) p1;
2925 const struct constant_descriptor_tree *const c2
2926 = (const struct constant_descriptor_tree *) p2;
2927 if (c1->hash != c2->hash)
2928 return 0;
2929 return compare_constant (c1->value, c2->value);
2932 /* Compare t1 and t2, and return 1 only if they are known to result in
2933 the same bit pattern on output. */
2935 static int
2936 compare_constant (const tree t1, const tree t2)
2938 enum tree_code typecode;
2940 if (t1 == NULL_TREE)
2941 return t2 == NULL_TREE;
2942 if (t2 == NULL_TREE)
2943 return 0;
2945 if (TREE_CODE (t1) != TREE_CODE (t2))
2946 return 0;
2948 switch (TREE_CODE (t1))
2950 case INTEGER_CST:
2951 /* Integer constants are the same only if the same width of type. */
2952 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2953 return 0;
2954 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2955 return 0;
2956 return tree_int_cst_equal (t1, t2);
2958 case REAL_CST:
2959 /* Real constants are the same only if the same width of type. */
2960 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2961 return 0;
2963 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
2965 case FIXED_CST:
2966 /* Fixed constants are the same only if the same width of type. */
2967 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2968 return 0;
2970 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
2972 case STRING_CST:
2973 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2974 return 0;
2976 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
2977 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
2978 TREE_STRING_LENGTH (t1)));
2980 case COMPLEX_CST:
2981 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
2982 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
2984 case VECTOR_CST:
2986 unsigned i;
2988 if (VECTOR_CST_NELTS (t1) != VECTOR_CST_NELTS (t2))
2989 return 0;
2991 for (i = 0; i < VECTOR_CST_NELTS (t1); ++i)
2992 if (!compare_constant (VECTOR_CST_ELT (t1, i),
2993 VECTOR_CST_ELT (t2, i)))
2994 return 0;
2996 return 1;
2999 case CONSTRUCTOR:
3001 vec<constructor_elt, va_gc> *v1, *v2;
3002 unsigned HOST_WIDE_INT idx;
3004 typecode = TREE_CODE (TREE_TYPE (t1));
3005 if (typecode != TREE_CODE (TREE_TYPE (t2)))
3006 return 0;
3008 if (typecode == ARRAY_TYPE)
3010 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
3011 /* For arrays, check that the sizes all match. */
3012 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
3013 || size_1 == -1
3014 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
3015 return 0;
3017 else
3019 /* For record and union constructors, require exact type
3020 equality. */
3021 if (TREE_TYPE (t1) != TREE_TYPE (t2))
3022 return 0;
3025 v1 = CONSTRUCTOR_ELTS (t1);
3026 v2 = CONSTRUCTOR_ELTS (t2);
3027 if (vec_safe_length (v1) != vec_safe_length (v2))
3028 return 0;
3030 for (idx = 0; idx < vec_safe_length (v1); ++idx)
3032 constructor_elt *c1 = &(*v1)[idx];
3033 constructor_elt *c2 = &(*v2)[idx];
3035 /* Check that each value is the same... */
3036 if (!compare_constant (c1->value, c2->value))
3037 return 0;
3038 /* ... and that they apply to the same fields! */
3039 if (typecode == ARRAY_TYPE)
3041 if (!compare_constant (c1->index, c2->index))
3042 return 0;
3044 else
3046 if (c1->index != c2->index)
3047 return 0;
3051 return 1;
3054 case ADDR_EXPR:
3055 case FDESC_EXPR:
3057 struct addr_const value1, value2;
3058 enum rtx_code code;
3059 int ret;
3061 decode_addr_const (t1, &value1);
3062 decode_addr_const (t2, &value2);
3064 if (value1.offset != value2.offset)
3065 return 0;
3067 code = GET_CODE (value1.base);
3068 if (code != GET_CODE (value2.base))
3069 return 0;
3071 switch (code)
3073 case SYMBOL_REF:
3074 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3075 break;
3077 case LABEL_REF:
3078 ret = (CODE_LABEL_NUMBER (XEXP (value1.base, 0))
3079 == CODE_LABEL_NUMBER (XEXP (value2.base, 0)));
3080 break;
3082 default:
3083 gcc_unreachable ();
3085 return ret;
3088 case PLUS_EXPR:
3089 case POINTER_PLUS_EXPR:
3090 case MINUS_EXPR:
3091 case RANGE_EXPR:
3092 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3093 && compare_constant (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3095 CASE_CONVERT:
3096 case VIEW_CONVERT_EXPR:
3097 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3099 default:
3100 return 0;
3103 gcc_unreachable ();
3106 /* Make a copy of the whole tree structure for a constant. This
3107 handles the same types of nodes that compare_constant handles. */
3109 static tree
3110 copy_constant (tree exp)
3112 switch (TREE_CODE (exp))
3114 case ADDR_EXPR:
3115 /* For ADDR_EXPR, we do not want to copy the decl whose address
3116 is requested. We do want to copy constants though. */
3117 if (CONSTANT_CLASS_P (TREE_OPERAND (exp, 0)))
3118 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
3119 copy_constant (TREE_OPERAND (exp, 0)));
3120 else
3121 return copy_node (exp);
3123 case INTEGER_CST:
3124 case REAL_CST:
3125 case FIXED_CST:
3126 case STRING_CST:
3127 return copy_node (exp);
3129 case COMPLEX_CST:
3130 return build_complex (TREE_TYPE (exp),
3131 copy_constant (TREE_REALPART (exp)),
3132 copy_constant (TREE_IMAGPART (exp)));
3134 case PLUS_EXPR:
3135 case POINTER_PLUS_EXPR:
3136 case MINUS_EXPR:
3137 return build2 (TREE_CODE (exp), TREE_TYPE (exp),
3138 copy_constant (TREE_OPERAND (exp, 0)),
3139 copy_constant (TREE_OPERAND (exp, 1)));
3141 CASE_CONVERT:
3142 case VIEW_CONVERT_EXPR:
3143 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
3144 copy_constant (TREE_OPERAND (exp, 0)));
3146 case VECTOR_CST:
3147 return build_vector (TREE_TYPE (exp), VECTOR_CST_ELTS (exp));
3149 case CONSTRUCTOR:
3151 tree copy = copy_node (exp);
3152 vec<constructor_elt, va_gc> *v;
3153 unsigned HOST_WIDE_INT idx;
3154 tree purpose, value;
3156 vec_alloc (v, vec_safe_length (CONSTRUCTOR_ELTS (exp)));
3157 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (exp), idx, purpose, value)
3159 constructor_elt ce = {purpose, copy_constant (value)};
3160 v->quick_push (ce);
3162 CONSTRUCTOR_ELTS (copy) = v;
3163 return copy;
3166 default:
3167 gcc_unreachable ();
3171 /* Return the section into which constant EXP should be placed. */
3173 static section *
3174 get_constant_section (tree exp, unsigned int align)
3176 return targetm.asm_out.select_section (exp,
3177 compute_reloc_for_constant (exp),
3178 align);
3181 /* Return the size of constant EXP in bytes. */
3183 static HOST_WIDE_INT
3184 get_constant_size (tree exp)
3186 HOST_WIDE_INT size;
3188 size = int_size_in_bytes (TREE_TYPE (exp));
3189 if (TREE_CODE (exp) == STRING_CST)
3190 size = MAX (TREE_STRING_LENGTH (exp), size);
3191 return size;
3194 /* Subroutine of output_constant_def:
3195 No constant equal to EXP is known to have been output.
3196 Make a constant descriptor to enter EXP in the hash table.
3197 Assign the label number and construct RTL to refer to the
3198 constant's location in memory.
3199 Caller is responsible for updating the hash table. */
3201 static struct constant_descriptor_tree *
3202 build_constant_desc (tree exp)
3204 struct constant_descriptor_tree *desc;
3205 rtx symbol, rtl;
3206 char label[256];
3207 int labelno;
3208 tree decl;
3210 desc = ggc_alloc<constant_descriptor_tree> ();
3211 desc->value = copy_constant (exp);
3213 /* Create a string containing the label name, in LABEL. */
3214 labelno = const_labelno++;
3215 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3217 /* Construct the VAR_DECL associated with the constant. */
3218 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3219 TREE_TYPE (exp));
3220 DECL_ARTIFICIAL (decl) = 1;
3221 DECL_IGNORED_P (decl) = 1;
3222 TREE_READONLY (decl) = 1;
3223 TREE_STATIC (decl) = 1;
3224 TREE_ADDRESSABLE (decl) = 1;
3225 /* We don't set the RTL yet as this would cause varpool to assume that the
3226 variable is referenced. Moreover, it would just be dropped in LTO mode.
3227 Instead we set the flag that will be recognized in make_decl_rtl. */
3228 DECL_IN_CONSTANT_POOL (decl) = 1;
3229 DECL_INITIAL (decl) = desc->value;
3230 /* ??? CONSTANT_ALIGNMENT hasn't been updated for vector types on most
3231 architectures so use DATA_ALIGNMENT as well, except for strings. */
3232 if (TREE_CODE (exp) == STRING_CST)
3234 #ifdef CONSTANT_ALIGNMENT
3235 DECL_ALIGN (decl) = CONSTANT_ALIGNMENT (exp, DECL_ALIGN (decl));
3236 #endif
3238 else
3239 align_variable (decl, 0);
3241 /* Now construct the SYMBOL_REF and the MEM. */
3242 if (use_object_blocks_p ())
3244 section *sect = get_constant_section (exp, DECL_ALIGN (decl));
3245 symbol = create_block_symbol (ggc_strdup (label),
3246 get_block_for_section (sect), -1);
3248 else
3249 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3250 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3251 SET_SYMBOL_REF_DECL (symbol, decl);
3252 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3254 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3255 set_mem_attributes (rtl, exp, 1);
3256 set_mem_alias_set (rtl, 0);
3257 set_mem_alias_set (rtl, const_alias_set);
3259 /* We cannot share RTX'es in pool entries.
3260 Mark this piece of RTL as required for unsharing. */
3261 RTX_FLAG (rtl, used) = 1;
3263 /* Set flags or add text to the name to record information, such as
3264 that it is a local symbol. If the name is changed, the macro
3265 ASM_OUTPUT_LABELREF will have to know how to strip this
3266 information. This call might invalidate our local variable
3267 SYMBOL; we can't use it afterward. */
3268 targetm.encode_section_info (exp, rtl, true);
3270 desc->rtl = rtl;
3272 return desc;
3275 /* Return an rtx representing a reference to constant data in memory
3276 for the constant expression EXP.
3278 If assembler code for such a constant has already been output,
3279 return an rtx to refer to it.
3280 Otherwise, output such a constant in memory
3281 and generate an rtx for it.
3283 If DEFER is nonzero, this constant can be deferred and output only
3284 if referenced in the function after all optimizations.
3286 `const_desc_table' records which constants already have label strings. */
3289 output_constant_def (tree exp, int defer)
3291 struct constant_descriptor_tree *desc;
3292 struct constant_descriptor_tree key;
3293 void **loc;
3295 /* Look up EXP in the table of constant descriptors. If we didn't find
3296 it, create a new one. */
3297 key.value = exp;
3298 key.hash = const_hash_1 (exp);
3299 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3301 desc = (struct constant_descriptor_tree *) *loc;
3302 if (desc == 0)
3304 desc = build_constant_desc (exp);
3305 desc->hash = key.hash;
3306 *loc = desc;
3309 maybe_output_constant_def_contents (desc, defer);
3310 return desc->rtl;
3313 /* Subroutine of output_constant_def: Decide whether or not we need to
3314 output the constant DESC now, and if so, do it. */
3315 static void
3316 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3317 int defer)
3319 rtx symbol = XEXP (desc->rtl, 0);
3320 tree exp = desc->value;
3322 if (flag_syntax_only)
3323 return;
3325 if (TREE_ASM_WRITTEN (exp))
3326 /* Already output; don't do it again. */
3327 return;
3329 /* We can always defer constants as long as the context allows
3330 doing so. */
3331 if (defer)
3333 /* Increment n_deferred_constants if it exists. It needs to be at
3334 least as large as the number of constants actually referred to
3335 by the function. If it's too small we'll stop looking too early
3336 and fail to emit constants; if it's too large we'll only look
3337 through the entire function when we could have stopped earlier. */
3338 if (cfun)
3339 n_deferred_constants++;
3340 return;
3343 output_constant_def_contents (symbol);
3346 /* Subroutine of output_constant_def_contents. Output the definition
3347 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3348 constant's alignment in bits. */
3350 static void
3351 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3353 HOST_WIDE_INT size;
3355 size = get_constant_size (exp);
3357 /* Do any machine/system dependent processing of the constant. */
3358 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3360 /* Output the value of EXP. */
3361 output_constant (exp, size, align);
3364 /* We must output the constant data referred to by SYMBOL; do so. */
3366 static void
3367 output_constant_def_contents (rtx symbol)
3369 tree decl = SYMBOL_REF_DECL (symbol);
3370 tree exp = DECL_INITIAL (decl);
3371 unsigned int align;
3372 bool asan_protected = false;
3374 /* Make sure any other constants whose addresses appear in EXP
3375 are assigned label numbers. */
3376 output_addressed_constants (exp);
3378 /* We are no longer deferring this constant. */
3379 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3381 if ((flag_sanitize & SANITIZE_ADDRESS)
3382 && TREE_CODE (exp) == STRING_CST
3383 && asan_protect_global (exp))
3385 asan_protected = true;
3386 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
3387 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
3390 /* If the constant is part of an object block, make sure that the
3391 decl has been positioned within its block, but do not write out
3392 its definition yet. output_object_blocks will do that later. */
3393 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3394 place_block_symbol (symbol);
3395 else
3397 align = DECL_ALIGN (decl);
3398 switch_to_section (get_constant_section (exp, align));
3399 if (align > BITS_PER_UNIT)
3400 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3401 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3402 if (asan_protected)
3404 HOST_WIDE_INT size = get_constant_size (exp);
3405 assemble_zeros (asan_red_zone_size (size));
3410 /* Look up EXP in the table of constant descriptors. Return the rtl
3411 if it has been emitted, else null. */
3414 lookup_constant_def (tree exp)
3416 struct constant_descriptor_tree *desc;
3417 struct constant_descriptor_tree key;
3419 key.value = exp;
3420 key.hash = const_hash_1 (exp);
3421 desc = (struct constant_descriptor_tree *)
3422 htab_find_with_hash (const_desc_htab, &key, key.hash);
3424 return (desc ? desc->rtl : NULL_RTX);
3427 /* Return a tree representing a reference to constant data in memory
3428 for the constant expression EXP.
3430 This is the counterpart of output_constant_def at the Tree level. */
3432 tree
3433 tree_output_constant_def (tree exp)
3435 struct constant_descriptor_tree *desc, key;
3436 void **loc;
3437 tree decl;
3439 /* Look up EXP in the table of constant descriptors. If we didn't find
3440 it, create a new one. */
3441 key.value = exp;
3442 key.hash = const_hash_1 (exp);
3443 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3445 desc = (struct constant_descriptor_tree *) *loc;
3446 if (desc == 0)
3448 desc = build_constant_desc (exp);
3449 desc->hash = key.hash;
3450 *loc = desc;
3453 decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3454 varpool_finalize_decl (decl);
3455 return decl;
3458 /* Used in the hash tables to avoid outputting the same constant
3459 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3460 are output once per function, not once per file. */
3461 /* ??? Only a few targets need per-function constant pools. Most
3462 can use one per-file pool. Should add a targetm bit to tell the
3463 difference. */
3465 struct GTY(()) rtx_constant_pool {
3466 /* Pointers to first and last constant in pool, as ordered by offset. */
3467 struct constant_descriptor_rtx *first;
3468 struct constant_descriptor_rtx *last;
3470 /* Hash facility for making memory-constants from constant rtl-expressions.
3471 It is used on RISC machines where immediate integer arguments and
3472 constant addresses are restricted so that such constants must be stored
3473 in memory. */
3474 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_htab;
3476 /* Current offset in constant pool (does not include any
3477 machine-specific header). */
3478 HOST_WIDE_INT offset;
3481 struct GTY((chain_next ("%h.next"))) constant_descriptor_rtx {
3482 struct constant_descriptor_rtx *next;
3483 rtx mem;
3484 rtx sym;
3485 rtx constant;
3486 HOST_WIDE_INT offset;
3487 hashval_t hash;
3488 enum machine_mode mode;
3489 unsigned int align;
3490 int labelno;
3491 int mark;
3494 /* Hash and compare functions for const_rtx_htab. */
3496 static hashval_t
3497 const_desc_rtx_hash (const void *ptr)
3499 const struct constant_descriptor_rtx *const desc
3500 = (const struct constant_descriptor_rtx *) ptr;
3501 return desc->hash;
3504 static int
3505 const_desc_rtx_eq (const void *a, const void *b)
3507 const struct constant_descriptor_rtx *const x
3508 = (const struct constant_descriptor_rtx *) a;
3509 const struct constant_descriptor_rtx *const y
3510 = (const struct constant_descriptor_rtx *) b;
3512 if (x->mode != y->mode)
3513 return 0;
3514 return rtx_equal_p (x->constant, y->constant);
3517 /* This is the worker function for const_rtx_hash, called via for_each_rtx. */
3519 static int
3520 const_rtx_hash_1 (rtx *xp, void *data)
3522 unsigned HOST_WIDE_INT hwi;
3523 enum machine_mode mode;
3524 enum rtx_code code;
3525 hashval_t h, *hp;
3526 rtx x;
3527 int i;
3529 x = *xp;
3530 code = GET_CODE (x);
3531 mode = GET_MODE (x);
3532 h = (hashval_t) code * 1048573 + mode;
3534 switch (code)
3536 case CONST_INT:
3537 hwi = INTVAL (x);
3539 fold_hwi:
3541 int shift = sizeof (hashval_t) * CHAR_BIT;
3542 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3544 h ^= (hashval_t) hwi;
3545 for (i = 1; i < n; ++i)
3547 hwi >>= shift;
3548 h ^= (hashval_t) hwi;
3551 break;
3553 case CONST_WIDE_INT:
3554 hwi = GET_MODE_PRECISION (mode);
3556 for (i = 0; i < CONST_WIDE_INT_NUNITS (x); i++)
3557 hwi ^= CONST_WIDE_INT_ELT (x, i);
3558 goto fold_hwi;
3561 case CONST_DOUBLE:
3562 if (TARGET_SUPPORTS_WIDE_INT == 0 && mode == VOIDmode)
3564 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3565 goto fold_hwi;
3567 else
3568 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3569 break;
3571 case CONST_FIXED:
3572 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3573 break;
3575 case CONST_VECTOR:
3577 int i;
3578 for (i = XVECLEN (x, 0); i-- > 0; )
3579 h = h * 251 + const_rtx_hash_1 (&XVECEXP (x, 0, i), data);
3581 break;
3583 case SYMBOL_REF:
3584 h ^= htab_hash_string (XSTR (x, 0));
3585 break;
3587 case LABEL_REF:
3588 h = h * 251 + CODE_LABEL_NUMBER (XEXP (x, 0));
3589 break;
3591 case UNSPEC:
3592 case UNSPEC_VOLATILE:
3593 h = h * 251 + XINT (x, 1);
3594 break;
3596 default:
3597 break;
3600 hp = (hashval_t *) data;
3601 *hp = *hp * 509 + h;
3602 return 0;
3605 /* Compute a hash value for X, which should be a constant. */
3607 static hashval_t
3608 const_rtx_hash (rtx x)
3610 hashval_t h = 0;
3611 for_each_rtx (&x, const_rtx_hash_1, &h);
3612 return h;
3616 /* Create and return a new rtx constant pool. */
3618 static struct rtx_constant_pool *
3619 create_constant_pool (void)
3621 struct rtx_constant_pool *pool;
3623 pool = ggc_alloc<rtx_constant_pool> ();
3624 pool->const_rtx_htab = htab_create_ggc (31, const_desc_rtx_hash,
3625 const_desc_rtx_eq, NULL);
3626 pool->first = NULL;
3627 pool->last = NULL;
3628 pool->offset = 0;
3629 return pool;
3632 /* Initialize constant pool hashing for a new function. */
3634 void
3635 init_varasm_status (void)
3637 crtl->varasm.pool = create_constant_pool ();
3638 crtl->varasm.deferred_constants = 0;
3641 /* Given a MINUS expression, simplify it if both sides
3642 include the same symbol. */
3645 simplify_subtraction (rtx x)
3647 rtx r = simplify_rtx (x);
3648 return r ? r : x;
3651 /* Given a constant rtx X, make (or find) a memory constant for its value
3652 and return a MEM rtx to refer to it in memory. */
3655 force_const_mem (enum machine_mode mode, rtx x)
3657 struct constant_descriptor_rtx *desc, tmp;
3658 struct rtx_constant_pool *pool;
3659 char label[256];
3660 rtx def, symbol;
3661 hashval_t hash;
3662 unsigned int align;
3663 void **slot;
3665 /* If we're not allowed to drop X into the constant pool, don't. */
3666 if (targetm.cannot_force_const_mem (mode, x))
3667 return NULL_RTX;
3669 /* Record that this function has used a constant pool entry. */
3670 crtl->uses_const_pool = 1;
3672 /* Decide which pool to use. */
3673 pool = (targetm.use_blocks_for_constant_p (mode, x)
3674 ? shared_constant_pool
3675 : crtl->varasm.pool);
3677 /* Lookup the value in the hashtable. */
3678 tmp.constant = x;
3679 tmp.mode = mode;
3680 hash = const_rtx_hash (x);
3681 slot = htab_find_slot_with_hash (pool->const_rtx_htab, &tmp, hash, INSERT);
3682 desc = (struct constant_descriptor_rtx *) *slot;
3684 /* If the constant was already present, return its memory. */
3685 if (desc)
3686 return copy_rtx (desc->mem);
3688 /* Otherwise, create a new descriptor. */
3689 desc = ggc_alloc<constant_descriptor_rtx> ();
3690 *slot = desc;
3692 /* Align the location counter as required by EXP's data type. */
3693 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3694 #ifdef CONSTANT_ALIGNMENT
3696 tree type = lang_hooks.types.type_for_mode (mode, 0);
3697 if (type != NULL_TREE)
3698 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3700 #endif
3702 pool->offset += (align / BITS_PER_UNIT) - 1;
3703 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3705 desc->next = NULL;
3706 desc->constant = copy_rtx (tmp.constant);
3707 desc->offset = pool->offset;
3708 desc->hash = hash;
3709 desc->mode = mode;
3710 desc->align = align;
3711 desc->labelno = const_labelno;
3712 desc->mark = 0;
3714 pool->offset += GET_MODE_SIZE (mode);
3715 if (pool->last)
3716 pool->last->next = desc;
3717 else
3718 pool->first = pool->last = desc;
3719 pool->last = desc;
3721 /* Create a string containing the label name, in LABEL. */
3722 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3723 ++const_labelno;
3725 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3726 the constants pool. */
3727 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3729 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3730 symbol = create_block_symbol (ggc_strdup (label),
3731 get_block_for_section (sect), -1);
3733 else
3734 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3735 desc->sym = symbol;
3736 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3737 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3738 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3740 /* Construct the MEM. */
3741 desc->mem = def = gen_const_mem (mode, symbol);
3742 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3743 set_mem_align (def, align);
3745 /* If we're dropping a label to the constant pool, make sure we
3746 don't delete it. */
3747 if (GET_CODE (x) == LABEL_REF)
3748 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3750 return copy_rtx (def);
3753 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3756 get_pool_constant (rtx addr)
3758 return SYMBOL_REF_CONSTANT (addr)->constant;
3761 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3762 and whether it has been output or not. */
3765 get_pool_constant_mark (rtx addr, bool *pmarked)
3767 struct constant_descriptor_rtx *desc;
3769 desc = SYMBOL_REF_CONSTANT (addr);
3770 *pmarked = (desc->mark != 0);
3771 return desc->constant;
3774 /* Similar, return the mode. */
3776 enum machine_mode
3777 get_pool_mode (const_rtx addr)
3779 return SYMBOL_REF_CONSTANT (addr)->mode;
3782 /* Return the size of the constant pool. */
3785 get_pool_size (void)
3787 return crtl->varasm.pool->offset;
3790 /* Worker function for output_constant_pool_1. Emit assembly for X
3791 in MODE with known alignment ALIGN. */
3793 static void
3794 output_constant_pool_2 (enum machine_mode mode, rtx x, unsigned int align)
3796 switch (GET_MODE_CLASS (mode))
3798 case MODE_FLOAT:
3799 case MODE_DECIMAL_FLOAT:
3801 REAL_VALUE_TYPE r;
3803 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3804 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3805 assemble_real (r, mode, align);
3806 break;
3809 case MODE_INT:
3810 case MODE_PARTIAL_INT:
3811 case MODE_FRACT:
3812 case MODE_UFRACT:
3813 case MODE_ACCUM:
3814 case MODE_UACCUM:
3815 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3816 break;
3818 case MODE_VECTOR_FLOAT:
3819 case MODE_VECTOR_INT:
3820 case MODE_VECTOR_FRACT:
3821 case MODE_VECTOR_UFRACT:
3822 case MODE_VECTOR_ACCUM:
3823 case MODE_VECTOR_UACCUM:
3825 int i, units;
3826 enum machine_mode submode = GET_MODE_INNER (mode);
3827 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3829 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3830 units = CONST_VECTOR_NUNITS (x);
3832 for (i = 0; i < units; i++)
3834 rtx elt = CONST_VECTOR_ELT (x, i);
3835 output_constant_pool_2 (submode, elt, i ? subalign : align);
3838 break;
3840 default:
3841 gcc_unreachable ();
3845 /* Worker function for output_constant_pool. Emit constant DESC,
3846 giving it ALIGN bits of alignment. */
3848 static void
3849 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3850 unsigned int align)
3852 rtx x, tmp;
3854 x = desc->constant;
3856 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3857 whose CODE_LABEL has been deleted. This can occur if a jump table
3858 is eliminated by optimization. If so, write a constant of zero
3859 instead. Note that this can also happen by turning the
3860 CODE_LABEL into a NOTE. */
3861 /* ??? This seems completely and utterly wrong. Certainly it's
3862 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3863 functioning even with INSN_DELETED_P and friends. */
3865 tmp = x;
3866 switch (GET_CODE (tmp))
3868 case CONST:
3869 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3870 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
3871 break;
3872 tmp = XEXP (XEXP (tmp, 0), 0);
3873 /* FALLTHRU */
3875 case LABEL_REF:
3876 tmp = XEXP (tmp, 0);
3877 gcc_assert (!INSN_DELETED_P (tmp));
3878 gcc_assert (!NOTE_P (tmp)
3879 || NOTE_KIND (tmp) != NOTE_INSN_DELETED);
3880 break;
3882 default:
3883 break;
3886 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3887 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3888 align, desc->labelno, done);
3889 #endif
3891 assemble_align (align);
3893 /* Output the label. */
3894 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3896 /* Output the data. */
3897 output_constant_pool_2 (desc->mode, x, align);
3899 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3900 sections have proper size. */
3901 if (align > GET_MODE_BITSIZE (desc->mode)
3902 && in_section
3903 && (in_section->common.flags & SECTION_MERGE))
3904 assemble_align (align);
3906 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3907 done:
3908 #endif
3909 return;
3912 /* Given a SYMBOL_REF CURRENT_RTX, mark it and all constants it refers
3913 to as used. Emit referenced deferred strings. This function can
3914 be used with for_each_rtx to mark all SYMBOL_REFs in an rtx. */
3916 static int
3917 mark_constant (rtx *current_rtx, void *data ATTRIBUTE_UNUSED)
3919 rtx x = *current_rtx;
3921 if (x == NULL_RTX || GET_CODE (x) != SYMBOL_REF)
3922 return 0;
3924 if (CONSTANT_POOL_ADDRESS_P (x))
3926 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
3927 if (desc->mark == 0)
3929 desc->mark = 1;
3930 for_each_rtx (&desc->constant, mark_constant, NULL);
3933 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3935 tree decl = SYMBOL_REF_DECL (x);
3936 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
3938 n_deferred_constants--;
3939 output_constant_def_contents (x);
3943 return -1;
3946 /* Look through appropriate parts of INSN, marking all entries in the
3947 constant pool which are actually being used. Entries that are only
3948 referenced by other constants are also marked as used. Emit
3949 deferred strings that are used. */
3951 static void
3952 mark_constants (rtx insn)
3954 if (!INSN_P (insn))
3955 return;
3957 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3958 insns, not any notes that may be attached. We don't want to mark
3959 a constant just because it happens to appear in a REG_EQUIV note. */
3960 if (GET_CODE (PATTERN (insn)) == SEQUENCE)
3962 rtx seq = PATTERN (insn);
3963 int i, n = XVECLEN (seq, 0);
3964 for (i = 0; i < n; ++i)
3966 rtx subinsn = XVECEXP (seq, 0, i);
3967 if (INSN_P (subinsn))
3968 for_each_rtx (&PATTERN (subinsn), mark_constant, NULL);
3971 else
3972 for_each_rtx (&PATTERN (insn), mark_constant, NULL);
3975 /* Look through the instructions for this function, and mark all the
3976 entries in POOL which are actually being used. Emit deferred constants
3977 which have indeed been used. */
3979 static void
3980 mark_constant_pool (void)
3982 rtx insn;
3984 if (!crtl->uses_const_pool && n_deferred_constants == 0)
3985 return;
3987 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3988 mark_constants (insn);
3991 /* Write all the constants in POOL. */
3993 static void
3994 output_constant_pool_contents (struct rtx_constant_pool *pool)
3996 struct constant_descriptor_rtx *desc;
3998 for (desc = pool->first; desc ; desc = desc->next)
3999 if (desc->mark)
4001 /* If the constant is part of an object_block, make sure that
4002 the constant has been positioned within its block, but do not
4003 write out its definition yet. output_object_blocks will do
4004 that later. */
4005 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
4006 && SYMBOL_REF_BLOCK (desc->sym))
4007 place_block_symbol (desc->sym);
4008 else
4010 switch_to_section (targetm.asm_out.select_rtx_section
4011 (desc->mode, desc->constant, desc->align));
4012 output_constant_pool_1 (desc, desc->align);
4017 /* Mark all constants that are used in the current function, then write
4018 out the function's private constant pool. */
4020 static void
4021 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
4022 tree fndecl ATTRIBUTE_UNUSED)
4024 struct rtx_constant_pool *pool = crtl->varasm.pool;
4026 /* It is possible for gcc to call force_const_mem and then to later
4027 discard the instructions which refer to the constant. In such a
4028 case we do not need to output the constant. */
4029 mark_constant_pool ();
4031 #ifdef ASM_OUTPUT_POOL_PROLOGUE
4032 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
4033 #endif
4035 output_constant_pool_contents (pool);
4037 #ifdef ASM_OUTPUT_POOL_EPILOGUE
4038 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
4039 #endif
4042 /* Write the contents of the shared constant pool. */
4044 void
4045 output_shared_constant_pool (void)
4047 output_constant_pool_contents (shared_constant_pool);
4050 /* Determine what kind of relocations EXP may need. */
4053 compute_reloc_for_constant (tree exp)
4055 int reloc = 0, reloc2;
4056 tree tem;
4058 switch (TREE_CODE (exp))
4060 case ADDR_EXPR:
4061 case FDESC_EXPR:
4062 /* Go inside any operations that get_inner_reference can handle and see
4063 if what's inside is a constant: no need to do anything here for
4064 addresses of variables or functions. */
4065 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4066 tem = TREE_OPERAND (tem, 0))
4069 if (TREE_CODE (tem) == MEM_REF
4070 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4072 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4073 break;
4076 if (!targetm.binds_local_p (tem))
4077 reloc |= 2;
4078 else
4079 reloc |= 1;
4080 break;
4082 case PLUS_EXPR:
4083 case POINTER_PLUS_EXPR:
4084 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4085 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4086 break;
4088 case MINUS_EXPR:
4089 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4090 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4091 /* The difference of two local labels is computable at link time. */
4092 if (reloc == 1 && reloc2 == 1)
4093 reloc = 0;
4094 else
4095 reloc |= reloc2;
4096 break;
4098 CASE_CONVERT:
4099 case VIEW_CONVERT_EXPR:
4100 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4101 break;
4103 case CONSTRUCTOR:
4105 unsigned HOST_WIDE_INT idx;
4106 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4107 if (tem != 0)
4108 reloc |= compute_reloc_for_constant (tem);
4110 break;
4112 default:
4113 break;
4115 return reloc;
4118 /* Find all the constants whose addresses are referenced inside of EXP,
4119 and make sure assembler code with a label has been output for each one.
4120 Indicate whether an ADDR_EXPR has been encountered. */
4122 static void
4123 output_addressed_constants (tree exp)
4125 tree tem;
4127 switch (TREE_CODE (exp))
4129 case ADDR_EXPR:
4130 case FDESC_EXPR:
4131 /* Go inside any operations that get_inner_reference can handle and see
4132 if what's inside is a constant: no need to do anything here for
4133 addresses of variables or functions. */
4134 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4135 tem = TREE_OPERAND (tem, 0))
4138 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4139 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4140 tem = DECL_INITIAL (tem);
4142 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4143 output_constant_def (tem, 0);
4145 if (TREE_CODE (tem) == MEM_REF)
4146 output_addressed_constants (TREE_OPERAND (tem, 0));
4147 break;
4149 case PLUS_EXPR:
4150 case POINTER_PLUS_EXPR:
4151 case MINUS_EXPR:
4152 output_addressed_constants (TREE_OPERAND (exp, 1));
4153 /* Fall through. */
4155 CASE_CONVERT:
4156 case VIEW_CONVERT_EXPR:
4157 output_addressed_constants (TREE_OPERAND (exp, 0));
4158 break;
4160 case CONSTRUCTOR:
4162 unsigned HOST_WIDE_INT idx;
4163 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4164 if (tem != 0)
4165 output_addressed_constants (tem);
4167 break;
4169 default:
4170 break;
4174 /* Whether a constructor CTOR is a valid static constant initializer if all
4175 its elements are. This used to be internal to initializer_constant_valid_p
4176 and has been exposed to let other functions like categorize_ctor_elements
4177 evaluate the property while walking a constructor for other purposes. */
4179 bool
4180 constructor_static_from_elts_p (const_tree ctor)
4182 return (TREE_CONSTANT (ctor)
4183 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4184 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4185 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4188 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4189 tree *cache);
4191 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4192 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4193 which are valid when ENDTYPE is an integer of any size; in
4194 particular, this does not accept a pointer minus a constant. This
4195 returns null_pointer_node if the VALUE is an absolute constant
4196 which can be used to initialize a static variable. Otherwise it
4197 returns NULL. */
4199 static tree
4200 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4202 tree op0, op1;
4204 if (!INTEGRAL_TYPE_P (endtype))
4205 return NULL_TREE;
4207 op0 = TREE_OPERAND (value, 0);
4208 op1 = TREE_OPERAND (value, 1);
4210 /* Like STRIP_NOPS except allow the operand mode to widen. This
4211 works around a feature of fold that simplifies (int)(p1 - p2) to
4212 ((int)p1 - (int)p2) under the theory that the narrower operation
4213 is cheaper. */
4215 while (CONVERT_EXPR_P (op0)
4216 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4218 tree inner = TREE_OPERAND (op0, 0);
4219 if (inner == error_mark_node
4220 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4221 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
4222 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4223 break;
4224 op0 = inner;
4227 while (CONVERT_EXPR_P (op1)
4228 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4230 tree inner = TREE_OPERAND (op1, 0);
4231 if (inner == error_mark_node
4232 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4233 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
4234 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4235 break;
4236 op1 = inner;
4239 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4240 if (!op0)
4241 return NULL_TREE;
4243 op1 = initializer_constant_valid_p_1 (op1, endtype,
4244 cache ? cache + 2 : NULL);
4245 /* Both initializers must be known. */
4246 if (op1)
4248 if (op0 == op1
4249 && (op0 == null_pointer_node
4250 || TREE_CODE (value) == MINUS_EXPR))
4251 return null_pointer_node;
4253 /* Support differences between labels. */
4254 if (TREE_CODE (op0) == LABEL_DECL
4255 && TREE_CODE (op1) == LABEL_DECL)
4256 return null_pointer_node;
4258 if (TREE_CODE (op0) == STRING_CST
4259 && TREE_CODE (op1) == STRING_CST
4260 && operand_equal_p (op0, op1, 1))
4261 return null_pointer_node;
4264 return NULL_TREE;
4267 /* Helper function of initializer_constant_valid_p.
4268 Return nonzero if VALUE is a valid constant-valued expression
4269 for use in initializing a static variable; one that can be an
4270 element of a "constant" initializer.
4272 Return null_pointer_node if the value is absolute;
4273 if it is relocatable, return the variable that determines the relocation.
4274 We assume that VALUE has been folded as much as possible;
4275 therefore, we do not need to check for such things as
4276 arithmetic-combinations of integers.
4278 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4280 static tree
4281 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4283 tree ret;
4285 switch (TREE_CODE (value))
4287 case CONSTRUCTOR:
4288 if (constructor_static_from_elts_p (value))
4290 unsigned HOST_WIDE_INT idx;
4291 tree elt;
4292 bool absolute = true;
4294 if (cache && cache[0] == value)
4295 return cache[1];
4296 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4298 tree reloc;
4299 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4300 NULL);
4301 if (!reloc)
4303 if (cache)
4305 cache[0] = value;
4306 cache[1] = NULL_TREE;
4308 return NULL_TREE;
4310 if (reloc != null_pointer_node)
4311 absolute = false;
4313 /* For a non-absolute relocation, there is no single
4314 variable that can be "the variable that determines the
4315 relocation." */
4316 if (cache)
4318 cache[0] = value;
4319 cache[1] = absolute ? null_pointer_node : error_mark_node;
4321 return absolute ? null_pointer_node : error_mark_node;
4324 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4326 case INTEGER_CST:
4327 case VECTOR_CST:
4328 case REAL_CST:
4329 case FIXED_CST:
4330 case STRING_CST:
4331 case COMPLEX_CST:
4332 return null_pointer_node;
4334 case ADDR_EXPR:
4335 case FDESC_EXPR:
4337 tree op0 = staticp (TREE_OPERAND (value, 0));
4338 if (op0)
4340 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4341 to be a constant, this is old-skool offsetof-like nonsense. */
4342 if (TREE_CODE (op0) == INDIRECT_REF
4343 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4344 return null_pointer_node;
4345 /* Taking the address of a nested function involves a trampoline,
4346 unless we don't need or want one. */
4347 if (TREE_CODE (op0) == FUNCTION_DECL
4348 && DECL_STATIC_CHAIN (op0)
4349 && !TREE_NO_TRAMPOLINE (value))
4350 return NULL_TREE;
4351 /* "&{...}" requires a temporary to hold the constructed
4352 object. */
4353 if (TREE_CODE (op0) == CONSTRUCTOR)
4354 return NULL_TREE;
4356 return op0;
4359 case NON_LVALUE_EXPR:
4360 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4361 endtype, cache);
4363 case VIEW_CONVERT_EXPR:
4365 tree src = TREE_OPERAND (value, 0);
4366 tree src_type = TREE_TYPE (src);
4367 tree dest_type = TREE_TYPE (value);
4369 /* Allow view-conversions from aggregate to non-aggregate type only
4370 if the bit pattern is fully preserved afterwards; otherwise, the
4371 RTL expander won't be able to apply a subsequent transformation
4372 to the underlying constructor. */
4373 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4375 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4376 return initializer_constant_valid_p_1 (src, endtype, cache);
4377 else
4378 return NULL_TREE;
4381 /* Allow all other kinds of view-conversion. */
4382 return initializer_constant_valid_p_1 (src, endtype, cache);
4385 CASE_CONVERT:
4387 tree src = TREE_OPERAND (value, 0);
4388 tree src_type = TREE_TYPE (src);
4389 tree dest_type = TREE_TYPE (value);
4391 /* Allow conversions between pointer types, floating-point
4392 types, and offset types. */
4393 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4394 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4395 || (TREE_CODE (dest_type) == OFFSET_TYPE
4396 && TREE_CODE (src_type) == OFFSET_TYPE))
4397 return initializer_constant_valid_p_1 (src, endtype, cache);
4399 /* Allow length-preserving conversions between integer types. */
4400 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4401 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4402 return initializer_constant_valid_p_1 (src, endtype, cache);
4404 /* Allow conversions between other integer types only if
4405 explicit value. */
4406 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type))
4408 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4409 if (inner == null_pointer_node)
4410 return null_pointer_node;
4411 break;
4414 /* Allow (int) &foo provided int is as wide as a pointer. */
4415 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4416 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4417 return initializer_constant_valid_p_1 (src, endtype, cache);
4419 /* Likewise conversions from int to pointers, but also allow
4420 conversions from 0. */
4421 if ((POINTER_TYPE_P (dest_type)
4422 || TREE_CODE (dest_type) == OFFSET_TYPE)
4423 && INTEGRAL_TYPE_P (src_type))
4425 if (TREE_CODE (src) == INTEGER_CST
4426 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4427 return null_pointer_node;
4428 if (integer_zerop (src))
4429 return null_pointer_node;
4430 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4431 return initializer_constant_valid_p_1 (src, endtype, cache);
4434 /* Allow conversions to struct or union types if the value
4435 inside is okay. */
4436 if (TREE_CODE (dest_type) == RECORD_TYPE
4437 || TREE_CODE (dest_type) == UNION_TYPE)
4438 return initializer_constant_valid_p_1 (src, endtype, cache);
4440 break;
4442 case POINTER_PLUS_EXPR:
4443 case PLUS_EXPR:
4444 /* Any valid floating-point constants will have been folded by now;
4445 with -frounding-math we hit this with addition of two constants. */
4446 if (TREE_CODE (endtype) == REAL_TYPE)
4447 return NULL_TREE;
4448 if (cache && cache[0] == value)
4449 return cache[1];
4450 if (! INTEGRAL_TYPE_P (endtype)
4451 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4453 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4454 tree valid0
4455 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4456 endtype, ncache);
4457 tree valid1
4458 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4459 endtype, ncache + 2);
4460 /* If either term is absolute, use the other term's relocation. */
4461 if (valid0 == null_pointer_node)
4462 ret = valid1;
4463 else if (valid1 == null_pointer_node)
4464 ret = valid0;
4465 /* Support narrowing pointer differences. */
4466 else
4467 ret = narrowing_initializer_constant_valid_p (value, endtype,
4468 ncache);
4470 else
4471 /* Support narrowing pointer differences. */
4472 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4473 if (cache)
4475 cache[0] = value;
4476 cache[1] = ret;
4478 return ret;
4480 case MINUS_EXPR:
4481 if (TREE_CODE (endtype) == REAL_TYPE)
4482 return NULL_TREE;
4483 if (cache && cache[0] == value)
4484 return cache[1];
4485 if (! INTEGRAL_TYPE_P (endtype)
4486 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4488 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4489 tree valid0
4490 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4491 endtype, ncache);
4492 tree valid1
4493 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4494 endtype, ncache + 2);
4495 /* Win if second argument is absolute. */
4496 if (valid1 == null_pointer_node)
4497 ret = valid0;
4498 /* Win if both arguments have the same relocation.
4499 Then the value is absolute. */
4500 else if (valid0 == valid1 && valid0 != 0)
4501 ret = null_pointer_node;
4502 /* Since GCC guarantees that string constants are unique in the
4503 generated code, a subtraction between two copies of the same
4504 constant string is absolute. */
4505 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4506 && valid1 && TREE_CODE (valid1) == STRING_CST
4507 && operand_equal_p (valid0, valid1, 1))
4508 ret = null_pointer_node;
4509 /* Support narrowing differences. */
4510 else
4511 ret = narrowing_initializer_constant_valid_p (value, endtype,
4512 ncache);
4514 else
4515 /* Support narrowing differences. */
4516 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4517 if (cache)
4519 cache[0] = value;
4520 cache[1] = ret;
4522 return ret;
4524 default:
4525 break;
4528 return NULL_TREE;
4531 /* Return nonzero if VALUE is a valid constant-valued expression
4532 for use in initializing a static variable; one that can be an
4533 element of a "constant" initializer.
4535 Return null_pointer_node if the value is absolute;
4536 if it is relocatable, return the variable that determines the relocation.
4537 We assume that VALUE has been folded as much as possible;
4538 therefore, we do not need to check for such things as
4539 arithmetic-combinations of integers. */
4540 tree
4541 initializer_constant_valid_p (tree value, tree endtype)
4543 return initializer_constant_valid_p_1 (value, endtype, NULL);
4546 /* Return true if VALUE is a valid constant-valued expression
4547 for use in initializing a static bit-field; one that can be
4548 an element of a "constant" initializer. */
4550 bool
4551 initializer_constant_valid_for_bitfield_p (tree value)
4553 /* For bitfields we support integer constants or possibly nested aggregates
4554 of such. */
4555 switch (TREE_CODE (value))
4557 case CONSTRUCTOR:
4559 unsigned HOST_WIDE_INT idx;
4560 tree elt;
4562 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4563 if (!initializer_constant_valid_for_bitfield_p (elt))
4564 return false;
4565 return true;
4568 case INTEGER_CST:
4569 case REAL_CST:
4570 return true;
4572 case VIEW_CONVERT_EXPR:
4573 case NON_LVALUE_EXPR:
4574 return
4575 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4577 default:
4578 break;
4581 return false;
4584 /* output_constructor outer state of relevance in recursive calls, typically
4585 for nested aggregate bitfields. */
4587 typedef struct {
4588 unsigned int bit_offset; /* current position in ... */
4589 int byte; /* ... the outer byte buffer. */
4590 } oc_outer_state;
4592 static unsigned HOST_WIDE_INT
4593 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int,
4594 oc_outer_state *);
4596 /* Output assembler code for constant EXP, with no label.
4597 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4598 Assumes output_addressed_constants has been done on EXP already.
4600 Generate at least SIZE bytes of assembler data, padding at the end
4601 with zeros if necessary. SIZE must always be specified. The returned
4602 value is the actual number of bytes of assembler data generated, which
4603 may be bigger than SIZE if the object contains a variable length field.
4605 SIZE is important for structure constructors,
4606 since trailing members may have been omitted from the constructor.
4607 It is also important for initialization of arrays from string constants
4608 since the full length of the string constant might not be wanted.
4609 It is also needed for initialization of unions, where the initializer's
4610 type is just one member, and that may not be as long as the union.
4612 There a case in which we would fail to output exactly SIZE bytes:
4613 for a structure constructor that wants to produce more than SIZE bytes.
4614 But such constructors will never be generated for any possible input.
4616 ALIGN is the alignment of the data in bits. */
4618 static unsigned HOST_WIDE_INT
4619 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align)
4621 enum tree_code code;
4622 unsigned HOST_WIDE_INT thissize;
4624 if (size == 0 || flag_syntax_only)
4625 return size;
4627 /* See if we're trying to initialize a pointer in a non-default mode
4628 to the address of some declaration somewhere. If the target says
4629 the mode is valid for pointers, assume the target has a way of
4630 resolving it. */
4631 if (TREE_CODE (exp) == NOP_EXPR
4632 && POINTER_TYPE_P (TREE_TYPE (exp))
4633 && targetm.addr_space.valid_pointer_mode
4634 (TYPE_MODE (TREE_TYPE (exp)),
4635 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4637 tree saved_type = TREE_TYPE (exp);
4639 /* Peel off any intermediate conversions-to-pointer for valid
4640 pointer modes. */
4641 while (TREE_CODE (exp) == NOP_EXPR
4642 && POINTER_TYPE_P (TREE_TYPE (exp))
4643 && targetm.addr_space.valid_pointer_mode
4644 (TYPE_MODE (TREE_TYPE (exp)),
4645 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4646 exp = TREE_OPERAND (exp, 0);
4648 /* If what we're left with is the address of something, we can
4649 convert the address to the final type and output it that
4650 way. */
4651 if (TREE_CODE (exp) == ADDR_EXPR)
4652 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4653 /* Likewise for constant ints. */
4654 else if (TREE_CODE (exp) == INTEGER_CST)
4655 exp = wide_int_to_tree (saved_type, exp);
4659 /* Eliminate any conversions since we'll be outputting the underlying
4660 constant. */
4661 while (CONVERT_EXPR_P (exp)
4662 || TREE_CODE (exp) == NON_LVALUE_EXPR
4663 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4665 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4666 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4668 /* Make sure eliminating the conversion is really a no-op, except with
4669 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4670 union types to allow for Ada unchecked unions. */
4671 if (type_size > op_size
4672 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4673 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4674 /* Keep the conversion. */
4675 break;
4676 else
4677 exp = TREE_OPERAND (exp, 0);
4680 code = TREE_CODE (TREE_TYPE (exp));
4681 thissize = int_size_in_bytes (TREE_TYPE (exp));
4683 /* Allow a constructor with no elements for any data type.
4684 This means to fill the space with zeros. */
4685 if (TREE_CODE (exp) == CONSTRUCTOR
4686 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4688 assemble_zeros (size);
4689 return size;
4692 if (TREE_CODE (exp) == FDESC_EXPR)
4694 #ifdef ASM_OUTPUT_FDESC
4695 HOST_WIDE_INT part = tree_to_shwi (TREE_OPERAND (exp, 1));
4696 tree decl = TREE_OPERAND (exp, 0);
4697 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4698 #else
4699 gcc_unreachable ();
4700 #endif
4701 return size;
4704 /* Now output the underlying data. If we've handling the padding, return.
4705 Otherwise, break and ensure SIZE is the size written. */
4706 switch (code)
4708 case BOOLEAN_TYPE:
4709 case INTEGER_TYPE:
4710 case ENUMERAL_TYPE:
4711 case POINTER_TYPE:
4712 case REFERENCE_TYPE:
4713 case OFFSET_TYPE:
4714 case FIXED_POINT_TYPE:
4715 case NULLPTR_TYPE:
4716 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
4717 EXPAND_INITIALIZER),
4718 MIN (size, thissize), align, 0))
4719 error ("initializer for integer/fixed-point value is too complicated");
4720 break;
4722 case REAL_TYPE:
4723 if (TREE_CODE (exp) != REAL_CST)
4724 error ("initializer for floating value is not a floating constant");
4725 else
4726 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)), align);
4727 break;
4729 case COMPLEX_TYPE:
4730 output_constant (TREE_REALPART (exp), thissize / 2, align);
4731 output_constant (TREE_IMAGPART (exp), thissize / 2,
4732 min_align (align, BITS_PER_UNIT * (thissize / 2)));
4733 break;
4735 case ARRAY_TYPE:
4736 case VECTOR_TYPE:
4737 switch (TREE_CODE (exp))
4739 case CONSTRUCTOR:
4740 return output_constructor (exp, size, align, NULL);
4741 case STRING_CST:
4742 thissize
4743 = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4744 assemble_string (TREE_STRING_POINTER (exp), thissize);
4745 break;
4746 case VECTOR_CST:
4748 enum machine_mode inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4749 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4750 int elt_size = GET_MODE_SIZE (inner);
4751 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align);
4752 thissize = elt_size;
4753 for (unsigned int i = 1; i < VECTOR_CST_NELTS (exp); i++)
4755 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign);
4756 thissize += elt_size;
4758 break;
4760 default:
4761 gcc_unreachable ();
4763 break;
4765 case RECORD_TYPE:
4766 case UNION_TYPE:
4767 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4768 return output_constructor (exp, size, align, NULL);
4770 case ERROR_MARK:
4771 return 0;
4773 default:
4774 gcc_unreachable ();
4777 if (size > thissize)
4778 assemble_zeros (size - thissize);
4780 return size;
4784 /* Subroutine of output_constructor, used for computing the size of
4785 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4786 type with an unspecified upper bound. */
4788 static unsigned HOST_WIDE_INT
4789 array_size_for_constructor (tree val)
4791 tree max_index;
4792 unsigned HOST_WIDE_INT cnt;
4793 tree index, value, tmp;
4794 offset_int i;
4796 /* This code used to attempt to handle string constants that are not
4797 arrays of single-bytes, but nothing else does, so there's no point in
4798 doing it here. */
4799 if (TREE_CODE (val) == STRING_CST)
4800 return TREE_STRING_LENGTH (val);
4802 max_index = NULL_TREE;
4803 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
4805 if (TREE_CODE (index) == RANGE_EXPR)
4806 index = TREE_OPERAND (index, 1);
4807 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
4808 max_index = index;
4811 if (max_index == NULL_TREE)
4812 return 0;
4814 /* Compute the total number of array elements. */
4815 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
4816 i = wi::to_offset (max_index) - wi::to_offset (tmp) + 1;
4818 /* Multiply by the array element unit size to find number of bytes. */
4819 i *= wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
4821 gcc_assert (wi::fits_uhwi_p (i));
4822 return i.to_uhwi ();
4825 /* Other datastructures + helpers for output_constructor. */
4827 /* output_constructor local state to support interaction with helpers. */
4829 typedef struct {
4831 /* Received arguments. */
4832 tree exp; /* Constructor expression. */
4833 tree type; /* Type of constructor expression. */
4834 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */
4835 unsigned int align; /* Known initial alignment. */
4836 tree min_index; /* Lower bound if specified for an array. */
4838 /* Output processing state. */
4839 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */
4840 int byte; /* Part of a bitfield byte yet to be output. */
4841 int last_relative_index; /* Implicit or explicit index of the last
4842 array element output within a bitfield. */
4843 bool byte_buffer_in_use; /* Whether BYTE is in use. */
4845 /* Current element. */
4846 tree field; /* Current field decl in a record. */
4847 tree val; /* Current element value. */
4848 tree index; /* Current element index. */
4850 } oc_local_state;
4852 /* Helper for output_constructor. From the current LOCAL state, output a
4853 RANGE_EXPR element. */
4855 static void
4856 output_constructor_array_range (oc_local_state *local)
4858 unsigned HOST_WIDE_INT fieldsize
4859 = int_size_in_bytes (TREE_TYPE (local->type));
4861 HOST_WIDE_INT lo_index
4862 = tree_to_shwi (TREE_OPERAND (local->index, 0));
4863 HOST_WIDE_INT hi_index
4864 = tree_to_shwi (TREE_OPERAND (local->index, 1));
4865 HOST_WIDE_INT index;
4867 unsigned int align2
4868 = min_align (local->align, fieldsize * BITS_PER_UNIT);
4870 for (index = lo_index; index <= hi_index; index++)
4872 /* Output the element's initial value. */
4873 if (local->val == NULL_TREE)
4874 assemble_zeros (fieldsize);
4875 else
4876 fieldsize = output_constant (local->val, fieldsize, align2);
4878 /* Count its size. */
4879 local->total_bytes += fieldsize;
4883 /* Helper for output_constructor. From the current LOCAL state, output a
4884 field element that is not true bitfield or part of an outer one. */
4886 static void
4887 output_constructor_regular_field (oc_local_state *local)
4889 /* Field size and position. Since this structure is static, we know the
4890 positions are constant. */
4891 unsigned HOST_WIDE_INT fieldsize;
4892 HOST_WIDE_INT fieldpos;
4894 unsigned int align2;
4896 if (local->index != NULL_TREE)
4898 /* Perform the index calculation in modulo arithmetic but
4899 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
4900 but we are using an unsigned sizetype. */
4901 unsigned prec = TYPE_PRECISION (sizetype);
4902 offset_int idx = wi::sext (wi::to_offset (local->index)
4903 - wi::to_offset (local->min_index), prec);
4904 fieldpos = (idx * wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (local->val))))
4905 .to_short_addr ();
4907 else if (local->field != NULL_TREE)
4908 fieldpos = int_byte_position (local->field);
4909 else
4910 fieldpos = 0;
4912 /* Output any buffered-up bit-fields preceding this element. */
4913 if (local->byte_buffer_in_use)
4915 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4916 local->total_bytes++;
4917 local->byte_buffer_in_use = false;
4920 /* Advance to offset of this element.
4921 Note no alignment needed in an array, since that is guaranteed
4922 if each element has the proper size. */
4923 if ((local->field != NULL_TREE || local->index != NULL_TREE)
4924 && fieldpos > local->total_bytes)
4926 assemble_zeros (fieldpos - local->total_bytes);
4927 local->total_bytes = fieldpos;
4930 /* Find the alignment of this element. */
4931 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
4933 /* Determine size this element should occupy. */
4934 if (local->field)
4936 fieldsize = 0;
4938 /* If this is an array with an unspecified upper bound,
4939 the initializer determines the size. */
4940 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
4941 but we cannot do this until the deprecated support for
4942 initializing zero-length array members is removed. */
4943 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
4944 && TYPE_DOMAIN (TREE_TYPE (local->field))
4945 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field))))
4947 fieldsize = array_size_for_constructor (local->val);
4948 /* Given a non-empty initialization, this field had
4949 better be last. */
4950 gcc_assert (!fieldsize || !DECL_CHAIN (local->field));
4952 else
4953 fieldsize = tree_to_uhwi (DECL_SIZE_UNIT (local->field));
4955 else
4956 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
4958 /* Output the element's initial value. */
4959 if (local->val == NULL_TREE)
4960 assemble_zeros (fieldsize);
4961 else
4962 fieldsize = output_constant (local->val, fieldsize, align2);
4964 /* Count its size. */
4965 local->total_bytes += fieldsize;
4968 /* Helper for output_constructor. From the LOCAL state, output an element
4969 that is a true bitfield or part of an outer one. BIT_OFFSET is the offset
4970 from the start of a possibly ongoing outer byte buffer. */
4972 static void
4973 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
4975 /* Bit size of this element. */
4976 HOST_WIDE_INT ebitsize
4977 = (local->field
4978 ? tree_to_uhwi (DECL_SIZE (local->field))
4979 : tree_to_uhwi (TYPE_SIZE (TREE_TYPE (local->type))));
4981 /* Relative index of this element if this is an array component. */
4982 HOST_WIDE_INT relative_index
4983 = (!local->field
4984 ? (local->index
4985 ? (tree_to_shwi (local->index)
4986 - tree_to_shwi (local->min_index))
4987 : local->last_relative_index + 1)
4988 : 0);
4990 /* Bit position of this element from the start of the containing
4991 constructor. */
4992 HOST_WIDE_INT constructor_relative_ebitpos
4993 = (local->field
4994 ? int_bit_position (local->field)
4995 : ebitsize * relative_index);
4997 /* Bit position of this element from the start of a possibly ongoing
4998 outer byte buffer. */
4999 HOST_WIDE_INT byte_relative_ebitpos
5000 = bit_offset + constructor_relative_ebitpos;
5002 /* From the start of a possibly ongoing outer byte buffer, offsets to
5003 the first bit of this element and to the first bit past the end of
5004 this element. */
5005 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
5006 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
5008 local->last_relative_index = relative_index;
5010 if (local->val == NULL_TREE)
5011 local->val = integer_zero_node;
5013 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
5014 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
5015 local->val = TREE_OPERAND (local->val, 0);
5017 if (TREE_CODE (local->val) != INTEGER_CST
5018 && TREE_CODE (local->val) != CONSTRUCTOR)
5020 error ("invalid initial value for member %qE", DECL_NAME (local->field));
5021 return;
5024 /* If this field does not start in this (or next) byte, skip some bytes. */
5025 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5027 /* Output remnant of any bit field in previous bytes. */
5028 if (local->byte_buffer_in_use)
5030 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5031 local->total_bytes++;
5032 local->byte_buffer_in_use = false;
5035 /* If still not at proper byte, advance to there. */
5036 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5038 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
5039 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
5040 local->total_bytes = next_offset / BITS_PER_UNIT;
5044 /* Set up the buffer if necessary. */
5045 if (!local->byte_buffer_in_use)
5047 local->byte = 0;
5048 if (ebitsize > 0)
5049 local->byte_buffer_in_use = true;
5052 /* If this is nested constructor, recurse passing the bit offset and the
5053 pending data, then retrieve the new pending data afterwards. */
5054 if (TREE_CODE (local->val) == CONSTRUCTOR)
5056 oc_outer_state temp_state;
5057 temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5058 temp_state.byte = local->byte;
5059 local->total_bytes
5060 += output_constructor (local->val, 0, 0, &temp_state);
5061 local->byte = temp_state.byte;
5062 return;
5065 /* Otherwise, we must split the element into pieces that fall within
5066 separate bytes, and combine each byte with previous or following
5067 bit-fields. */
5068 while (next_offset < end_offset)
5070 int this_time;
5071 int shift;
5072 HOST_WIDE_INT value;
5073 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5074 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5076 /* Advance from byte to byte within this element when necessary. */
5077 while (next_byte != local->total_bytes)
5079 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5080 local->total_bytes++;
5081 local->byte = 0;
5084 /* Number of bits we can process at once (all part of the same byte). */
5085 this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5086 if (BYTES_BIG_ENDIAN)
5088 /* On big-endian machine, take the most significant bits (of the
5089 bits that are significant) first and put them into bytes from
5090 the most significant end. */
5091 shift = end_offset - next_offset - this_time;
5093 /* Don't try to take a bunch of bits that cross
5094 the word boundary in the INTEGER_CST. We can
5095 only select bits from one element. */
5096 if ((shift / HOST_BITS_PER_WIDE_INT)
5097 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5099 const int end = shift + this_time - 1;
5100 shift = end & -HOST_BITS_PER_WIDE_INT;
5101 this_time = end - shift + 1;
5104 /* Now get the bits from the appropriate constant word. */
5105 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5106 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5108 /* Get the result. This works only when:
5109 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5110 local->byte |= (((value >> shift)
5111 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5112 << (BITS_PER_UNIT - this_time - next_bit));
5114 else
5116 /* On little-endian machines, take the least significant bits of
5117 the value first and pack them starting at the least significant
5118 bits of the bytes. */
5119 shift = next_offset - byte_relative_ebitpos;
5121 /* Don't try to take a bunch of bits that cross
5122 the word boundary in the INTEGER_CST. We can
5123 only select bits from one element. */
5124 if ((shift / HOST_BITS_PER_WIDE_INT)
5125 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5126 this_time
5127 = HOST_BITS_PER_WIDE_INT - (shift & (HOST_BITS_PER_WIDE_INT - 1));
5129 /* Now get the bits from the appropriate constant word. */
5130 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5131 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5133 /* Get the result. This works only when:
5134 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5135 local->byte |= (((value >> shift)
5136 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5137 << next_bit);
5140 next_offset += this_time;
5141 local->byte_buffer_in_use = true;
5145 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5146 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5147 caller output state of relevance in recursive invocations. */
5149 static unsigned HOST_WIDE_INT
5150 output_constructor (tree exp, unsigned HOST_WIDE_INT size,
5151 unsigned int align, oc_outer_state *outer)
5153 unsigned HOST_WIDE_INT cnt;
5154 constructor_elt *ce;
5156 oc_local_state local;
5158 /* Setup our local state to communicate with helpers. */
5159 local.exp = exp;
5160 local.type = TREE_TYPE (exp);
5161 local.size = size;
5162 local.align = align;
5163 if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5164 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5165 else
5166 local.min_index = NULL_TREE;
5168 local.total_bytes = 0;
5169 local.byte_buffer_in_use = outer != NULL;
5170 local.byte = outer ? outer->byte : 0;
5171 local.last_relative_index = -1;
5173 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5175 /* As CE goes through the elements of the constant, FIELD goes through the
5176 structure fields if the constant is a structure. If the constant is a
5177 union, we override this by getting the field from the TREE_LIST element.
5178 But the constant could also be an array. Then FIELD is zero.
5180 There is always a maximum of one element in the chain LINK for unions
5181 (even if the initializer in a source program incorrectly contains
5182 more one). */
5184 if (TREE_CODE (local.type) == RECORD_TYPE)
5185 local.field = TYPE_FIELDS (local.type);
5186 else
5187 local.field = NULL_TREE;
5189 for (cnt = 0;
5190 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5191 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5193 local.val = ce->value;
5194 local.index = NULL_TREE;
5196 /* The element in a union constructor specifies the proper field
5197 or index. */
5198 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5199 local.field = ce->index;
5201 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5202 local.index = ce->index;
5204 if (local.field && flag_verbose_asm)
5205 fprintf (asm_out_file, "%s %s:\n",
5206 ASM_COMMENT_START,
5207 DECL_NAME (local.field)
5208 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5209 : "<anonymous>");
5211 /* Eliminate the marker that makes a cast not be an lvalue. */
5212 if (local.val != NULL_TREE)
5213 STRIP_NOPS (local.val);
5215 /* Output the current element, using the appropriate helper ... */
5217 /* For an array slice not part of an outer bitfield. */
5218 if (!outer
5219 && local.index != NULL_TREE
5220 && TREE_CODE (local.index) == RANGE_EXPR)
5221 output_constructor_array_range (&local);
5223 /* For a field that is neither a true bitfield nor part of an outer one,
5224 known to be at least byte aligned and multiple-of-bytes long. */
5225 else if (!outer
5226 && (local.field == NULL_TREE
5227 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5228 output_constructor_regular_field (&local);
5230 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5231 supported for scalar fields, so we may need to convert first. */
5232 else
5234 if (TREE_CODE (local.val) == REAL_CST)
5235 local.val
5236 = fold_unary (VIEW_CONVERT_EXPR,
5237 build_nonstandard_integer_type
5238 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5239 local.val);
5240 output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5244 /* If we are not at toplevel, save the pending data for our caller.
5245 Otherwise output the pending data and padding zeros as needed. */
5246 if (outer)
5247 outer->byte = local.byte;
5248 else
5250 if (local.byte_buffer_in_use)
5252 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5253 local.total_bytes++;
5256 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5258 assemble_zeros (local.size - local.total_bytes);
5259 local.total_bytes = local.size;
5263 return local.total_bytes;
5266 /* Mark DECL as weak. */
5268 static void
5269 mark_weak (tree decl)
5271 DECL_WEAK (decl) = 1;
5273 if (DECL_RTL_SET_P (decl)
5274 && MEM_P (DECL_RTL (decl))
5275 && XEXP (DECL_RTL (decl), 0)
5276 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5277 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5280 /* Merge weak status between NEWDECL and OLDDECL. */
5282 void
5283 merge_weak (tree newdecl, tree olddecl)
5285 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5287 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5289 tree *pwd;
5290 /* We put the NEWDECL on the weak_decls list at some point
5291 and OLDDECL as well. Keep just OLDDECL on the list. */
5292 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5293 if (TREE_VALUE (*pwd) == newdecl)
5295 *pwd = TREE_CHAIN (*pwd);
5296 break;
5299 return;
5302 if (DECL_WEAK (newdecl))
5304 tree wd;
5306 /* NEWDECL is weak, but OLDDECL is not. */
5308 /* If we already output the OLDDECL, we're in trouble; we can't
5309 go back and make it weak. This should never happen in
5310 unit-at-a-time compilation. */
5311 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5313 /* If we've already generated rtl referencing OLDDECL, we may
5314 have done so in a way that will not function properly with
5315 a weak symbol. Again in unit-at-a-time this should be
5316 impossible. */
5317 gcc_assert (!TREE_USED (olddecl)
5318 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5320 if (TARGET_SUPPORTS_WEAK)
5322 /* We put the NEWDECL on the weak_decls list at some point.
5323 Replace it with the OLDDECL. */
5324 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5325 if (TREE_VALUE (wd) == newdecl)
5327 TREE_VALUE (wd) = olddecl;
5328 break;
5330 /* We may not find the entry on the list. If NEWDECL is a
5331 weak alias, then we will have already called
5332 globalize_decl to remove the entry; in that case, we do
5333 not need to do anything. */
5336 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5337 mark_weak (olddecl);
5339 else
5340 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5341 weak. Just update NEWDECL to indicate that it's weak too. */
5342 mark_weak (newdecl);
5345 /* Declare DECL to be a weak symbol. */
5347 void
5348 declare_weak (tree decl)
5350 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5351 if (! TREE_PUBLIC (decl))
5352 error ("weak declaration of %q+D must be public", decl);
5353 else if (!TARGET_SUPPORTS_WEAK)
5354 warning (0, "weak declaration of %q+D not supported", decl);
5356 mark_weak (decl);
5357 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5358 DECL_ATTRIBUTES (decl)
5359 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5362 static void
5363 weak_finish_1 (tree decl)
5365 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5366 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5367 #endif
5369 if (! TREE_USED (decl))
5370 return;
5372 #ifdef ASM_WEAKEN_DECL
5373 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5374 #else
5375 #ifdef ASM_WEAKEN_LABEL
5376 ASM_WEAKEN_LABEL (asm_out_file, name);
5377 #else
5378 #ifdef ASM_OUTPUT_WEAK_ALIAS
5380 static bool warn_once = 0;
5381 if (! warn_once)
5383 warning (0, "only weak aliases are supported in this configuration");
5384 warn_once = 1;
5386 return;
5388 #endif
5389 #endif
5390 #endif
5393 /* Fiven an assembly name, find the decl it is associated with. */
5394 static tree
5395 find_decl (tree target)
5397 symtab_node *node = symtab_node_for_asm (target);
5398 if (node)
5399 return node->decl;
5400 return NULL_TREE;
5403 /* This TREE_LIST contains weakref targets. */
5405 static GTY(()) tree weakref_targets;
5407 /* Emit any pending weak declarations. */
5409 void
5410 weak_finish (void)
5412 tree t;
5414 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5416 tree alias_decl = TREE_PURPOSE (t);
5417 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5419 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5420 /* Remove alias_decl from the weak list, but leave entries for
5421 the target alone. */
5422 target = NULL_TREE;
5423 #ifndef ASM_OUTPUT_WEAKREF
5424 else if (! TREE_SYMBOL_REFERENCED (target))
5426 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5427 defined, otherwise we and weak_finish_1 would use
5428 different macros. */
5429 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5430 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5431 # else
5432 tree decl = find_decl (target);
5434 if (! decl)
5436 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5437 TREE_CODE (alias_decl), target,
5438 TREE_TYPE (alias_decl));
5440 DECL_EXTERNAL (decl) = 1;
5441 TREE_PUBLIC (decl) = 1;
5442 DECL_ARTIFICIAL (decl) = 1;
5443 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5444 TREE_USED (decl) = 1;
5447 weak_finish_1 (decl);
5448 # endif
5450 #endif
5453 tree *p;
5454 tree t2;
5456 /* Remove the alias and the target from the pending weak list
5457 so that we do not emit any .weak directives for the former,
5458 nor multiple .weak directives for the latter. */
5459 for (p = &weak_decls; (t2 = *p) ; )
5461 if (TREE_VALUE (t2) == alias_decl
5462 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5463 *p = TREE_CHAIN (t2);
5464 else
5465 p = &TREE_CHAIN (t2);
5468 /* Remove other weakrefs to the same target, to speed things up. */
5469 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5471 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5472 *p = TREE_CHAIN (t2);
5473 else
5474 p = &TREE_CHAIN (t2);
5479 for (t = weak_decls; t; t = TREE_CHAIN (t))
5481 tree decl = TREE_VALUE (t);
5483 weak_finish_1 (decl);
5487 /* Emit the assembly bits to indicate that DECL is globally visible. */
5489 static void
5490 globalize_decl (tree decl)
5493 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5494 if (DECL_WEAK (decl))
5496 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5497 tree *p, t;
5499 #ifdef ASM_WEAKEN_DECL
5500 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5501 #else
5502 ASM_WEAKEN_LABEL (asm_out_file, name);
5503 #endif
5505 /* Remove this function from the pending weak list so that
5506 we do not emit multiple .weak directives for it. */
5507 for (p = &weak_decls; (t = *p) ; )
5509 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5510 *p = TREE_CHAIN (t);
5511 else
5512 p = &TREE_CHAIN (t);
5515 /* Remove weakrefs to the same target from the pending weakref
5516 list, for the same reason. */
5517 for (p = &weakref_targets; (t = *p) ; )
5519 if (DECL_ASSEMBLER_NAME (decl)
5520 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5521 *p = TREE_CHAIN (t);
5522 else
5523 p = &TREE_CHAIN (t);
5526 return;
5528 #endif
5530 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5533 vec<alias_pair, va_gc> *alias_pairs;
5535 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5536 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5537 tree node is DECL to have the value of the tree node TARGET. */
5539 void
5540 do_assemble_alias (tree decl, tree target)
5542 /* Emulated TLS had better not get this var. */
5543 gcc_assert (!(!targetm.have_tls
5544 && TREE_CODE (decl) == VAR_DECL
5545 && DECL_THREAD_LOCAL_P (decl)));
5547 if (TREE_ASM_WRITTEN (decl))
5548 return;
5550 /* We must force creation of DECL_RTL for debug info generation, even though
5551 we don't use it here. */
5552 make_decl_rtl (decl);
5554 TREE_ASM_WRITTEN (decl) = 1;
5555 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5557 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5559 ultimate_transparent_alias_target (&target);
5561 if (!TREE_SYMBOL_REFERENCED (target))
5562 weakref_targets = tree_cons (decl, target, weakref_targets);
5564 #ifdef ASM_OUTPUT_WEAKREF
5565 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5566 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5567 IDENTIFIER_POINTER (target));
5568 #else
5569 if (!TARGET_SUPPORTS_WEAK)
5571 error_at (DECL_SOURCE_LOCATION (decl),
5572 "weakref is not supported in this configuration");
5573 return;
5575 #endif
5576 return;
5579 #ifdef ASM_OUTPUT_DEF
5580 /* Make name accessible from other files, if appropriate. */
5582 if (TREE_PUBLIC (decl))
5584 globalize_decl (decl);
5585 maybe_assemble_visibility (decl);
5587 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5589 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5590 if (targetm.has_ifunc_p ())
5591 ASM_OUTPUT_TYPE_DIRECTIVE
5592 (asm_out_file, IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5593 IFUNC_ASM_TYPE);
5594 else
5595 #endif
5596 error_at (DECL_SOURCE_LOCATION (decl),
5597 "ifunc is not supported on this target");
5600 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5601 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5602 # else
5603 ASM_OUTPUT_DEF (asm_out_file,
5604 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5605 IDENTIFIER_POINTER (target));
5606 # endif
5607 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5609 const char *name;
5610 tree *p, t;
5612 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5613 # ifdef ASM_WEAKEN_DECL
5614 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5615 # else
5616 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5617 # endif
5618 /* Remove this function from the pending weak list so that
5619 we do not emit multiple .weak directives for it. */
5620 for (p = &weak_decls; (t = *p) ; )
5621 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5622 *p = TREE_CHAIN (t);
5623 else
5624 p = &TREE_CHAIN (t);
5626 /* Remove weakrefs to the same target from the pending weakref
5627 list, for the same reason. */
5628 for (p = &weakref_targets; (t = *p) ; )
5630 if (DECL_ASSEMBLER_NAME (decl)
5631 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5632 *p = TREE_CHAIN (t);
5633 else
5634 p = &TREE_CHAIN (t);
5637 #endif
5640 /* Emit an assembler directive to make the symbol for DECL an alias to
5641 the symbol for TARGET. */
5643 void
5644 assemble_alias (tree decl, tree target)
5646 tree target_decl;
5648 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5650 tree alias = DECL_ASSEMBLER_NAME (decl);
5652 ultimate_transparent_alias_target (&target);
5654 if (alias == target)
5655 error ("weakref %q+D ultimately targets itself", decl);
5656 if (TREE_PUBLIC (decl))
5657 error ("weakref %q+D must have static linkage", decl);
5659 else
5661 #if !defined (ASM_OUTPUT_DEF)
5662 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5663 error_at (DECL_SOURCE_LOCATION (decl),
5664 "alias definitions not supported in this configuration");
5665 TREE_ASM_WRITTEN (decl) = 1;
5666 return;
5667 # else
5668 if (!DECL_WEAK (decl))
5670 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5671 error_at (DECL_SOURCE_LOCATION (decl),
5672 "ifunc is not supported in this configuration");
5673 else
5674 error_at (DECL_SOURCE_LOCATION (decl),
5675 "only weak aliases are supported in this configuration");
5676 TREE_ASM_WRITTEN (decl) = 1;
5677 return;
5679 # endif
5680 #endif
5682 TREE_USED (decl) = 1;
5684 /* Allow aliases to aliases. */
5685 if (TREE_CODE (decl) == FUNCTION_DECL)
5686 cgraph_get_create_node (decl)->alias = true;
5687 else
5688 varpool_node_for_decl (decl)->alias = true;
5690 /* If the target has already been emitted, we don't have to queue the
5691 alias. This saves a tad of memory. */
5692 if (cgraph_global_info_ready)
5693 target_decl = find_decl (target);
5694 else
5695 target_decl= NULL;
5696 if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5697 || cgraph_state >= CGRAPH_STATE_EXPANSION)
5698 do_assemble_alias (decl, target);
5699 else
5701 alias_pair p = {decl, target};
5702 vec_safe_push (alias_pairs, p);
5706 /* Record and output a table of translations from original function
5707 to its transaction aware clone. Note that tm_pure functions are
5708 considered to be their own clone. */
5710 static GTY((if_marked ("tree_map_marked_p"), param_is (struct tree_map)))
5711 htab_t tm_clone_hash;
5713 void
5714 record_tm_clone_pair (tree o, tree n)
5716 struct tree_map **slot, *h;
5718 if (tm_clone_hash == NULL)
5719 tm_clone_hash = htab_create_ggc (32, tree_map_hash, tree_map_eq, 0);
5721 h = ggc_alloc<tree_map> ();
5722 h->hash = htab_hash_pointer (o);
5723 h->base.from = o;
5724 h->to = n;
5726 slot = (struct tree_map **)
5727 htab_find_slot_with_hash (tm_clone_hash, h, h->hash, INSERT);
5728 *slot = h;
5731 tree
5732 get_tm_clone_pair (tree o)
5734 if (tm_clone_hash)
5736 struct tree_map *h, in;
5738 in.base.from = o;
5739 in.hash = htab_hash_pointer (o);
5740 h = (struct tree_map *) htab_find_with_hash (tm_clone_hash,
5741 &in, in.hash);
5742 if (h)
5743 return h->to;
5745 return NULL_TREE;
5748 typedef struct tm_alias_pair
5750 unsigned int uid;
5751 tree from;
5752 tree to;
5753 } tm_alias_pair;
5756 /* Helper function for finish_tm_clone_pairs. Dump a hash table entry
5757 into a VEC in INFO. */
5759 static int
5760 dump_tm_clone_to_vec (void **slot, void *info)
5762 struct tree_map *map = (struct tree_map *) *slot;
5763 vec<tm_alias_pair> *tm_alias_pairs = (vec<tm_alias_pair> *) info;
5764 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
5765 tm_alias_pairs->safe_push (p);
5766 return 1;
5769 /* Dump the actual pairs to the .tm_clone_table section. */
5771 static void
5772 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
5774 unsigned i;
5775 tm_alias_pair *p;
5776 bool switched = false;
5778 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
5780 tree src = p->from;
5781 tree dst = p->to;
5782 struct cgraph_node *src_n = cgraph_get_node (src);
5783 struct cgraph_node *dst_n = cgraph_get_node (dst);
5785 /* The function ipa_tm_create_version() marks the clone as needed if
5786 the original function was needed. But we also mark the clone as
5787 needed if we ever called the clone indirectly through
5788 TM_GETTMCLONE. If neither of these are true, we didn't generate
5789 a clone, and we didn't call it indirectly... no sense keeping it
5790 in the clone table. */
5791 if (!dst_n || !dst_n->definition)
5792 continue;
5794 /* This covers the case where we have optimized the original
5795 function away, and only access the transactional clone. */
5796 if (!src_n || !src_n->definition)
5797 continue;
5799 if (!switched)
5801 switch_to_section (targetm.asm_out.tm_clone_table_section ());
5802 assemble_align (POINTER_SIZE);
5803 switched = true;
5806 assemble_integer (XEXP (DECL_RTL (src), 0),
5807 POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
5808 assemble_integer (XEXP (DECL_RTL (dst), 0),
5809 POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
5813 /* Provide a default for the tm_clone_table section. */
5815 section *
5816 default_clone_table_section (void)
5818 return get_named_section (NULL, ".tm_clone_table", 3);
5821 /* Helper comparison function for qsorting by the DECL_UID stored in
5822 alias_pair->emitted_diags. */
5824 static int
5825 tm_alias_pair_cmp (const void *x, const void *y)
5827 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
5828 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
5829 if (p1->uid < p2->uid)
5830 return -1;
5831 if (p1->uid > p2->uid)
5832 return 1;
5833 return 0;
5836 void
5837 finish_tm_clone_pairs (void)
5839 vec<tm_alias_pair> tm_alias_pairs = vNULL;
5841 if (tm_clone_hash == NULL)
5842 return;
5844 /* We need a determenistic order for the .tm_clone_table, otherwise
5845 we will get bootstrap comparison failures, so dump the hash table
5846 to a vector, sort it, and dump the vector. */
5848 /* Dump the hashtable to a vector. */
5849 htab_traverse_noresize (tm_clone_hash, dump_tm_clone_to_vec,
5850 (void *) &tm_alias_pairs);
5851 /* Sort it. */
5852 tm_alias_pairs.qsort (tm_alias_pair_cmp);
5854 /* Dump it. */
5855 dump_tm_clone_pairs (tm_alias_pairs);
5857 htab_delete (tm_clone_hash);
5858 tm_clone_hash = NULL;
5859 tm_alias_pairs.release ();
5863 /* Emit an assembler directive to set symbol for DECL visibility to
5864 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
5866 void
5867 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
5868 int vis ATTRIBUTE_UNUSED)
5870 #ifdef HAVE_GAS_HIDDEN
5871 static const char * const visibility_types[] = {
5872 NULL, "protected", "hidden", "internal"
5875 const char *name, *type;
5877 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5878 type = visibility_types[vis];
5880 fprintf (asm_out_file, "\t.%s\t", type);
5881 assemble_name (asm_out_file, name);
5882 fprintf (asm_out_file, "\n");
5883 #else
5884 if (!DECL_ARTIFICIAL (decl))
5885 warning (OPT_Wattributes, "visibility attribute not supported "
5886 "in this configuration; ignored");
5887 #endif
5890 /* A helper function to call assemble_visibility when needed for a decl. */
5893 maybe_assemble_visibility (tree decl)
5895 enum symbol_visibility vis = DECL_VISIBILITY (decl);
5897 if (vis != VISIBILITY_DEFAULT)
5899 targetm.asm_out.assemble_visibility (decl, vis);
5900 return 1;
5902 else
5903 return 0;
5906 /* Returns 1 if the target configuration supports defining public symbols
5907 so that one of them will be chosen at link time instead of generating a
5908 multiply-defined symbol error, whether through the use of weak symbols or
5909 a target-specific mechanism for having duplicates discarded. */
5912 supports_one_only (void)
5914 if (SUPPORTS_ONE_ONLY)
5915 return 1;
5916 return TARGET_SUPPORTS_WEAK;
5919 /* Set up DECL as a public symbol that can be defined in multiple
5920 translation units without generating a linker error. */
5922 void
5923 make_decl_one_only (tree decl, tree comdat_group)
5925 struct symtab_node *symbol;
5926 gcc_assert (TREE_CODE (decl) == VAR_DECL
5927 || TREE_CODE (decl) == FUNCTION_DECL);
5929 TREE_PUBLIC (decl) = 1;
5931 if (TREE_CODE (decl) == VAR_DECL)
5932 symbol = varpool_node_for_decl (decl);
5933 else
5934 symbol = cgraph_get_create_node (decl);
5936 if (SUPPORTS_ONE_ONLY)
5938 #ifdef MAKE_DECL_ONE_ONLY
5939 MAKE_DECL_ONE_ONLY (decl);
5940 #endif
5941 symbol->set_comdat_group (comdat_group);
5943 else if (TREE_CODE (decl) == VAR_DECL
5944 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node))
5945 DECL_COMMON (decl) = 1;
5946 else
5948 gcc_assert (TARGET_SUPPORTS_WEAK);
5949 DECL_WEAK (decl) = 1;
5953 void
5954 init_varasm_once (void)
5956 section_htab = htab_create_ggc (31, section_entry_hash,
5957 section_entry_eq, NULL);
5958 object_block_htab = htab_create_ggc (31, object_block_entry_hash,
5959 object_block_entry_eq, NULL);
5960 const_desc_htab = htab_create_ggc (1009, const_desc_hash,
5961 const_desc_eq, NULL);
5963 const_alias_set = new_alias_set ();
5964 shared_constant_pool = create_constant_pool ();
5966 #ifdef TEXT_SECTION_ASM_OP
5967 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
5968 TEXT_SECTION_ASM_OP);
5969 #endif
5971 #ifdef DATA_SECTION_ASM_OP
5972 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5973 DATA_SECTION_ASM_OP);
5974 #endif
5976 #ifdef SDATA_SECTION_ASM_OP
5977 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5978 SDATA_SECTION_ASM_OP);
5979 #endif
5981 #ifdef READONLY_DATA_SECTION_ASM_OP
5982 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
5983 READONLY_DATA_SECTION_ASM_OP);
5984 #endif
5986 #ifdef CTORS_SECTION_ASM_OP
5987 ctors_section = get_unnamed_section (0, output_section_asm_op,
5988 CTORS_SECTION_ASM_OP);
5989 #endif
5991 #ifdef DTORS_SECTION_ASM_OP
5992 dtors_section = get_unnamed_section (0, output_section_asm_op,
5993 DTORS_SECTION_ASM_OP);
5994 #endif
5996 #ifdef BSS_SECTION_ASM_OP
5997 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5998 output_section_asm_op,
5999 BSS_SECTION_ASM_OP);
6000 #endif
6002 #ifdef SBSS_SECTION_ASM_OP
6003 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6004 output_section_asm_op,
6005 SBSS_SECTION_ASM_OP);
6006 #endif
6008 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6009 | SECTION_COMMON, emit_tls_common);
6010 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6011 | SECTION_COMMON, emit_local);
6012 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6013 | SECTION_COMMON, emit_common);
6015 #if defined ASM_OUTPUT_ALIGNED_BSS
6016 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
6017 emit_bss);
6018 #endif
6020 targetm.asm_out.init_sections ();
6022 if (readonly_data_section == NULL)
6023 readonly_data_section = text_section;
6025 #ifdef ASM_OUTPUT_EXTERNAL
6026 pending_assemble_externals_set = pointer_set_create ();
6027 #endif
6030 enum tls_model
6031 decl_default_tls_model (const_tree decl)
6033 enum tls_model kind;
6034 bool is_local;
6036 is_local = targetm.binds_local_p (decl);
6037 if (!flag_shlib)
6039 if (is_local)
6040 kind = TLS_MODEL_LOCAL_EXEC;
6041 else
6042 kind = TLS_MODEL_INITIAL_EXEC;
6045 /* Local dynamic is inefficient when we're not combining the
6046 parts of the address. */
6047 else if (optimize && is_local)
6048 kind = TLS_MODEL_LOCAL_DYNAMIC;
6049 else
6050 kind = TLS_MODEL_GLOBAL_DYNAMIC;
6051 if (kind < flag_tls_default)
6052 kind = flag_tls_default;
6054 return kind;
6057 /* Select a set of attributes for section NAME based on the properties
6058 of DECL and whether or not RELOC indicates that DECL's initializer
6059 might contain runtime relocations.
6061 We make the section read-only and executable for a function decl,
6062 read-only for a const data decl, and writable for a non-const data decl. */
6064 unsigned int
6065 default_section_type_flags (tree decl, const char *name, int reloc)
6067 unsigned int flags;
6069 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6070 flags = SECTION_CODE;
6071 else if (decl)
6073 enum section_category category
6074 = categorize_decl_for_section (decl, reloc);
6075 if (decl_readonly_section_1 (category))
6076 flags = 0;
6077 else if (category == SECCAT_DATA_REL_RO
6078 || category == SECCAT_DATA_REL_RO_LOCAL)
6079 flags = SECTION_WRITE | SECTION_RELRO;
6080 else
6081 flags = SECTION_WRITE;
6083 else
6085 flags = SECTION_WRITE;
6086 if (strcmp (name, ".data.rel.ro") == 0
6087 || strcmp (name, ".data.rel.ro.local") == 0)
6088 flags |= SECTION_RELRO;
6091 if (decl && DECL_P (decl) && DECL_COMDAT_GROUP (decl))
6092 flags |= SECTION_LINKONCE;
6094 if (strcmp (name, ".vtable_map_vars") == 0)
6095 flags |= SECTION_LINKONCE;
6097 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6098 flags |= SECTION_TLS | SECTION_WRITE;
6100 if (strcmp (name, ".bss") == 0
6101 || strncmp (name, ".bss.", 5) == 0
6102 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6103 || strcmp (name, ".sbss") == 0
6104 || strncmp (name, ".sbss.", 6) == 0
6105 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6106 flags |= SECTION_BSS;
6108 if (strcmp (name, ".tdata") == 0
6109 || strncmp (name, ".tdata.", 7) == 0
6110 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6111 flags |= SECTION_TLS;
6113 if (strcmp (name, ".tbss") == 0
6114 || strncmp (name, ".tbss.", 6) == 0
6115 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6116 flags |= SECTION_TLS | SECTION_BSS;
6118 /* These three sections have special ELF types. They are neither
6119 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
6120 want to print a section type (@progbits or @nobits). If someone
6121 is silly enough to emit code or TLS variables to one of these
6122 sections, then don't handle them specially. */
6123 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6124 && (strcmp (name, ".init_array") == 0
6125 || strcmp (name, ".fini_array") == 0
6126 || strcmp (name, ".preinit_array") == 0))
6127 flags |= SECTION_NOTYPE;
6129 return flags;
6132 /* Return true if the target supports some form of global BSS,
6133 either through bss_noswitch_section, or by selecting a BSS
6134 section in TARGET_ASM_SELECT_SECTION. */
6136 bool
6137 have_global_bss_p (void)
6139 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6142 /* Output assembly to switch to section NAME with attribute FLAGS.
6143 Four variants for common object file formats. */
6145 void
6146 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6147 unsigned int flags ATTRIBUTE_UNUSED,
6148 tree decl ATTRIBUTE_UNUSED)
6150 /* Some object formats don't support named sections at all. The
6151 front-end should already have flagged this as an error. */
6152 gcc_unreachable ();
6155 #ifndef TLS_SECTION_ASM_FLAG
6156 #define TLS_SECTION_ASM_FLAG 'T'
6157 #endif
6159 void
6160 default_elf_asm_named_section (const char *name, unsigned int flags,
6161 tree decl ATTRIBUTE_UNUSED)
6163 char flagchars[10], *f = flagchars;
6165 /* If we have already declared this section, we can use an
6166 abbreviated form to switch back to it -- unless this section is
6167 part of a COMDAT groups, in which case GAS requires the full
6168 declaration every time. */
6169 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6170 && (flags & SECTION_DECLARED))
6172 fprintf (asm_out_file, "\t.section\t%s\n", name);
6173 return;
6176 if (!(flags & SECTION_DEBUG))
6177 *f++ = 'a';
6178 if (flags & SECTION_EXCLUDE)
6179 *f++ = 'e';
6180 if (flags & SECTION_WRITE)
6181 *f++ = 'w';
6182 if (flags & SECTION_CODE)
6183 *f++ = 'x';
6184 if (flags & SECTION_SMALL)
6185 *f++ = 's';
6186 if (flags & SECTION_MERGE)
6187 *f++ = 'M';
6188 if (flags & SECTION_STRINGS)
6189 *f++ = 'S';
6190 if (flags & SECTION_TLS)
6191 *f++ = TLS_SECTION_ASM_FLAG;
6192 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6193 *f++ = 'G';
6194 *f = '\0';
6196 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6198 if (!(flags & SECTION_NOTYPE))
6200 const char *type;
6201 const char *format;
6203 if (flags & SECTION_BSS)
6204 type = "nobits";
6205 else
6206 type = "progbits";
6208 format = ",@%s";
6209 /* On platforms that use "@" as the assembly comment character,
6210 use "%" instead. */
6211 if (strcmp (ASM_COMMENT_START, "@") == 0)
6212 format = ",%%%s";
6213 fprintf (asm_out_file, format, type);
6215 if (flags & SECTION_ENTSIZE)
6216 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6217 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6219 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6220 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6221 else
6222 fprintf (asm_out_file, ",%s,comdat",
6223 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6227 putc ('\n', asm_out_file);
6230 void
6231 default_coff_asm_named_section (const char *name, unsigned int flags,
6232 tree decl ATTRIBUTE_UNUSED)
6234 char flagchars[8], *f = flagchars;
6236 if (flags & SECTION_WRITE)
6237 *f++ = 'w';
6238 if (flags & SECTION_CODE)
6239 *f++ = 'x';
6240 *f = '\0';
6242 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6245 void
6246 default_pe_asm_named_section (const char *name, unsigned int flags,
6247 tree decl)
6249 default_coff_asm_named_section (name, flags, decl);
6251 if (flags & SECTION_LINKONCE)
6253 /* Functions may have been compiled at various levels of
6254 optimization so we can't use `same_size' here.
6255 Instead, have the linker pick one. */
6256 fprintf (asm_out_file, "\t.linkonce %s\n",
6257 (flags & SECTION_CODE ? "discard" : "same_size"));
6261 /* The lame default section selector. */
6263 section *
6264 default_select_section (tree decl, int reloc,
6265 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6267 if (DECL_P (decl))
6269 if (decl_readonly_section (decl, reloc))
6270 return readonly_data_section;
6272 else if (TREE_CODE (decl) == CONSTRUCTOR)
6274 if (! ((flag_pic && reloc)
6275 || !TREE_READONLY (decl)
6276 || TREE_SIDE_EFFECTS (decl)
6277 || !TREE_CONSTANT (decl)))
6278 return readonly_data_section;
6280 else if (TREE_CODE (decl) == STRING_CST)
6281 return readonly_data_section;
6282 else if (! (flag_pic && reloc))
6283 return readonly_data_section;
6285 return data_section;
6288 enum section_category
6289 categorize_decl_for_section (const_tree decl, int reloc)
6291 enum section_category ret;
6293 if (TREE_CODE (decl) == FUNCTION_DECL)
6294 return SECCAT_TEXT;
6295 else if (TREE_CODE (decl) == STRING_CST)
6297 if ((flag_sanitize & SANITIZE_ADDRESS)
6298 && asan_protect_global (CONST_CAST_TREE (decl)))
6299 /* or !flag_merge_constants */
6300 return SECCAT_RODATA;
6301 else
6302 return SECCAT_RODATA_MERGE_STR;
6304 else if (TREE_CODE (decl) == VAR_DECL)
6306 if (bss_initializer_p (decl))
6307 ret = SECCAT_BSS;
6308 else if (! TREE_READONLY (decl)
6309 || TREE_SIDE_EFFECTS (decl)
6310 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
6312 /* Here the reloc_rw_mask is not testing whether the section should
6313 be read-only or not, but whether the dynamic link will have to
6314 do something. If so, we wish to segregate the data in order to
6315 minimize cache misses inside the dynamic linker. */
6316 if (reloc & targetm.asm_out.reloc_rw_mask ())
6317 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6318 else
6319 ret = SECCAT_DATA;
6321 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6322 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6323 else if (reloc || flag_merge_constants < 2
6324 || ((flag_sanitize & SANITIZE_ADDRESS)
6325 && asan_protect_global (CONST_CAST_TREE (decl))))
6326 /* C and C++ don't allow different variables to share the same
6327 location. -fmerge-all-constants allows even that (at the
6328 expense of not conforming). */
6329 ret = SECCAT_RODATA;
6330 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6331 ret = SECCAT_RODATA_MERGE_STR_INIT;
6332 else
6333 ret = SECCAT_RODATA_MERGE_CONST;
6335 else if (TREE_CODE (decl) == CONSTRUCTOR)
6337 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6338 || TREE_SIDE_EFFECTS (decl)
6339 || ! TREE_CONSTANT (decl))
6340 ret = SECCAT_DATA;
6341 else
6342 ret = SECCAT_RODATA;
6344 else
6345 ret = SECCAT_RODATA;
6347 /* There are no read-only thread-local sections. */
6348 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6350 /* Note that this would be *just* SECCAT_BSS, except that there's
6351 no concept of a read-only thread-local-data section. */
6352 if (ret == SECCAT_BSS
6353 || (flag_zero_initialized_in_bss
6354 && initializer_zerop (DECL_INITIAL (decl))))
6355 ret = SECCAT_TBSS;
6356 else
6357 ret = SECCAT_TDATA;
6360 /* If the target uses small data sections, select it. */
6361 else if (targetm.in_small_data_p (decl))
6363 if (ret == SECCAT_BSS)
6364 ret = SECCAT_SBSS;
6365 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6366 ret = SECCAT_SRODATA;
6367 else
6368 ret = SECCAT_SDATA;
6371 return ret;
6374 static bool
6375 decl_readonly_section_1 (enum section_category category)
6377 switch (category)
6379 case SECCAT_RODATA:
6380 case SECCAT_RODATA_MERGE_STR:
6381 case SECCAT_RODATA_MERGE_STR_INIT:
6382 case SECCAT_RODATA_MERGE_CONST:
6383 case SECCAT_SRODATA:
6384 return true;
6385 default:
6386 return false;
6390 bool
6391 decl_readonly_section (const_tree decl, int reloc)
6393 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6396 /* Select a section based on the above categorization. */
6398 section *
6399 default_elf_select_section (tree decl, int reloc,
6400 unsigned HOST_WIDE_INT align)
6402 const char *sname;
6403 switch (categorize_decl_for_section (decl, reloc))
6405 case SECCAT_TEXT:
6406 /* We're not supposed to be called on FUNCTION_DECLs. */
6407 gcc_unreachable ();
6408 case SECCAT_RODATA:
6409 return readonly_data_section;
6410 case SECCAT_RODATA_MERGE_STR:
6411 return mergeable_string_section (decl, align, 0);
6412 case SECCAT_RODATA_MERGE_STR_INIT:
6413 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6414 case SECCAT_RODATA_MERGE_CONST:
6415 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6416 case SECCAT_SRODATA:
6417 sname = ".sdata2";
6418 break;
6419 case SECCAT_DATA:
6420 return data_section;
6421 case SECCAT_DATA_REL:
6422 sname = ".data.rel";
6423 break;
6424 case SECCAT_DATA_REL_LOCAL:
6425 sname = ".data.rel.local";
6426 break;
6427 case SECCAT_DATA_REL_RO:
6428 sname = ".data.rel.ro";
6429 break;
6430 case SECCAT_DATA_REL_RO_LOCAL:
6431 sname = ".data.rel.ro.local";
6432 break;
6433 case SECCAT_SDATA:
6434 sname = ".sdata";
6435 break;
6436 case SECCAT_TDATA:
6437 sname = ".tdata";
6438 break;
6439 case SECCAT_BSS:
6440 if (bss_section)
6441 return bss_section;
6442 sname = ".bss";
6443 break;
6444 case SECCAT_SBSS:
6445 sname = ".sbss";
6446 break;
6447 case SECCAT_TBSS:
6448 sname = ".tbss";
6449 break;
6450 default:
6451 gcc_unreachable ();
6454 return get_named_section (decl, sname, reloc);
6457 /* Construct a unique section name based on the decl name and the
6458 categorization performed above. */
6460 void
6461 default_unique_section (tree decl, int reloc)
6463 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6464 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6465 const char *prefix, *name, *linkonce;
6466 char *string;
6468 switch (categorize_decl_for_section (decl, reloc))
6470 case SECCAT_TEXT:
6471 prefix = one_only ? ".t" : ".text";
6472 break;
6473 case SECCAT_RODATA:
6474 case SECCAT_RODATA_MERGE_STR:
6475 case SECCAT_RODATA_MERGE_STR_INIT:
6476 case SECCAT_RODATA_MERGE_CONST:
6477 prefix = one_only ? ".r" : ".rodata";
6478 break;
6479 case SECCAT_SRODATA:
6480 prefix = one_only ? ".s2" : ".sdata2";
6481 break;
6482 case SECCAT_DATA:
6483 prefix = one_only ? ".d" : ".data";
6484 break;
6485 case SECCAT_DATA_REL:
6486 prefix = one_only ? ".d.rel" : ".data.rel";
6487 break;
6488 case SECCAT_DATA_REL_LOCAL:
6489 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6490 break;
6491 case SECCAT_DATA_REL_RO:
6492 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6493 break;
6494 case SECCAT_DATA_REL_RO_LOCAL:
6495 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6496 break;
6497 case SECCAT_SDATA:
6498 prefix = one_only ? ".s" : ".sdata";
6499 break;
6500 case SECCAT_BSS:
6501 prefix = one_only ? ".b" : ".bss";
6502 break;
6503 case SECCAT_SBSS:
6504 prefix = one_only ? ".sb" : ".sbss";
6505 break;
6506 case SECCAT_TDATA:
6507 prefix = one_only ? ".td" : ".tdata";
6508 break;
6509 case SECCAT_TBSS:
6510 prefix = one_only ? ".tb" : ".tbss";
6511 break;
6512 default:
6513 gcc_unreachable ();
6516 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
6517 name = targetm.strip_name_encoding (name);
6519 /* If we're using one_only, then there needs to be a .gnu.linkonce
6520 prefix to the section name. */
6521 linkonce = one_only ? ".gnu.linkonce" : "";
6523 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6525 DECL_SECTION_NAME (decl) = build_string (strlen (string), string);
6528 /* Like compute_reloc_for_constant, except for an RTX. The return value
6529 is a mask for which bit 1 indicates a global relocation, and bit 0
6530 indicates a local relocation. */
6532 static int
6533 compute_reloc_for_rtx_1 (rtx *xp, void *data)
6535 int *preloc = (int *) data;
6536 rtx x = *xp;
6538 switch (GET_CODE (x))
6540 case SYMBOL_REF:
6541 *preloc |= SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6542 break;
6543 case LABEL_REF:
6544 *preloc |= 1;
6545 break;
6546 default:
6547 break;
6550 return 0;
6553 static int
6554 compute_reloc_for_rtx (rtx x)
6556 int reloc;
6558 switch (GET_CODE (x))
6560 case CONST:
6561 case SYMBOL_REF:
6562 case LABEL_REF:
6563 reloc = 0;
6564 for_each_rtx (&x, compute_reloc_for_rtx_1, &reloc);
6565 return reloc;
6567 default:
6568 return 0;
6572 section *
6573 default_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
6574 rtx x,
6575 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6577 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6578 return data_section;
6579 else
6580 return readonly_data_section;
6583 section *
6584 default_elf_select_rtx_section (enum machine_mode mode, rtx x,
6585 unsigned HOST_WIDE_INT align)
6587 int reloc = compute_reloc_for_rtx (x);
6589 /* ??? Handle small data here somehow. */
6591 if (reloc & targetm.asm_out.reloc_rw_mask ())
6593 if (reloc == 1)
6594 return get_named_section (NULL, ".data.rel.ro.local", 1);
6595 else
6596 return get_named_section (NULL, ".data.rel.ro", 3);
6599 return mergeable_constant_section (mode, align, 0);
6602 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6604 void
6605 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6607 rtx symbol;
6608 int flags;
6610 /* Careful not to prod global register variables. */
6611 if (!MEM_P (rtl))
6612 return;
6613 symbol = XEXP (rtl, 0);
6614 if (GET_CODE (symbol) != SYMBOL_REF)
6615 return;
6617 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6618 if (TREE_CODE (decl) == FUNCTION_DECL)
6619 flags |= SYMBOL_FLAG_FUNCTION;
6620 if (targetm.binds_local_p (decl))
6621 flags |= SYMBOL_FLAG_LOCAL;
6622 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6623 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6624 else if (targetm.in_small_data_p (decl))
6625 flags |= SYMBOL_FLAG_SMALL;
6626 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6627 being PUBLIC, the thing *must* be defined in this translation unit.
6628 Prevent this buglet from being propagated into rtl code as well. */
6629 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6630 flags |= SYMBOL_FLAG_EXTERNAL;
6632 SYMBOL_REF_FLAGS (symbol) = flags;
6635 /* By default, we do nothing for encode_section_info, so we need not
6636 do anything but discard the '*' marker. */
6638 const char *
6639 default_strip_name_encoding (const char *str)
6641 return str + (*str == '*');
6644 #ifdef ASM_OUTPUT_DEF
6645 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6646 anchor relative to ".", the current section position. */
6648 void
6649 default_asm_output_anchor (rtx symbol)
6651 char buffer[100];
6653 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6654 SYMBOL_REF_BLOCK_OFFSET (symbol));
6655 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6657 #endif
6659 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6661 bool
6662 default_use_anchors_for_symbol_p (const_rtx symbol)
6664 section *sect;
6665 tree decl;
6667 /* Don't use anchors for mergeable sections. The linker might move
6668 the objects around. */
6669 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6670 if (sect->common.flags & SECTION_MERGE)
6671 return false;
6673 /* Don't use anchors for small data sections. The small data register
6674 acts as an anchor for such sections. */
6675 if (sect->common.flags & SECTION_SMALL)
6676 return false;
6678 decl = SYMBOL_REF_DECL (symbol);
6679 if (decl && DECL_P (decl))
6681 /* Don't use section anchors for decls that might be defined or
6682 usurped by other modules. */
6683 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6684 return false;
6686 /* Don't use section anchors for decls that will be placed in a
6687 small data section. */
6688 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6689 one above. The problem is that we only use SECTION_SMALL for
6690 sections that should be marked as small in the section directive. */
6691 if (targetm.in_small_data_p (decl))
6692 return false;
6694 return true;
6697 /* Return true when RESOLUTION indicate that symbol will be bound to the
6698 definition provided by current .o file. */
6700 static bool
6701 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
6703 return (resolution == LDPR_PREVAILING_DEF
6704 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6705 || resolution == LDPR_PREVAILING_DEF_IRONLY);
6708 /* Return true when RESOLUTION indicate that symbol will be bound locally
6709 within current executable or DSO. */
6711 static bool
6712 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
6714 return (resolution == LDPR_PREVAILING_DEF
6715 || resolution == LDPR_PREVAILING_DEF_IRONLY
6716 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6717 || resolution == LDPR_PREEMPTED_REG
6718 || resolution == LDPR_PREEMPTED_IR
6719 || resolution == LDPR_RESOLVED_IR
6720 || resolution == LDPR_RESOLVED_EXEC);
6723 /* Assume ELF-ish defaults, since that's pretty much the most liberal
6724 wrt cross-module name binding. */
6726 bool
6727 default_binds_local_p (const_tree exp)
6729 return default_binds_local_p_1 (exp, flag_shlib);
6732 bool
6733 default_binds_local_p_1 (const_tree exp, int shlib)
6735 bool local_p;
6736 bool resolved_locally = false;
6737 bool resolved_to_local_def = false;
6739 /* With resolution file in hands, take look into resolutions.
6740 We can't just return true for resolved_locally symbols,
6741 because dynamic linking might overwrite symbols
6742 in shared libraries. */
6743 if (TREE_CODE (exp) == VAR_DECL && TREE_PUBLIC (exp)
6744 && (TREE_STATIC (exp) || DECL_EXTERNAL (exp)))
6746 varpool_node *vnode = varpool_get_node (exp);
6747 if (vnode && (resolution_local_p (vnode->resolution) || vnode->in_other_partition))
6748 resolved_locally = true;
6749 if (vnode
6750 && resolution_to_local_definition_p (vnode->resolution))
6751 resolved_to_local_def = true;
6753 else if (TREE_CODE (exp) == FUNCTION_DECL && TREE_PUBLIC (exp))
6755 struct cgraph_node *node = cgraph_get_node (exp);
6756 if (node
6757 && (resolution_local_p (node->resolution) || node->in_other_partition))
6758 resolved_locally = true;
6759 if (node
6760 && resolution_to_local_definition_p (node->resolution))
6761 resolved_to_local_def = true;
6764 /* A non-decl is an entry in the constant pool. */
6765 if (!DECL_P (exp))
6766 local_p = true;
6767 /* Weakrefs may not bind locally, even though the weakref itself is always
6768 static and therefore local. Similarly, the resolver for ifunc functions
6769 might resolve to a non-local function.
6770 FIXME: We can resolve the weakref case more curefuly by looking at the
6771 weakref alias. */
6772 else if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
6773 || (TREE_CODE (exp) == FUNCTION_DECL
6774 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
6775 local_p = false;
6776 /* Static variables are always local. */
6777 else if (! TREE_PUBLIC (exp))
6778 local_p = true;
6779 /* A variable is local if the user has said explicitly that it will
6780 be. */
6781 else if ((DECL_VISIBILITY_SPECIFIED (exp)
6782 || resolved_to_local_def)
6783 && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6784 local_p = true;
6785 /* Variables defined outside this object might not be local. */
6786 else if (DECL_EXTERNAL (exp) && !resolved_locally)
6787 local_p = false;
6788 /* If defined in this object and visibility is not default, must be
6789 local. */
6790 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6791 local_p = true;
6792 /* Default visibility weak data can be overridden by a strong symbol
6793 in another module and so are not local. */
6794 else if (DECL_WEAK (exp)
6795 && !resolved_locally)
6796 local_p = false;
6797 /* If PIC, then assume that any global name can be overridden by
6798 symbols resolved from other modules. */
6799 else if (shlib)
6800 local_p = false;
6801 /* Uninitialized COMMON variable may be unified with symbols
6802 resolved from other modules. */
6803 else if (DECL_COMMON (exp)
6804 && !resolved_locally
6805 && (DECL_INITIAL (exp) == NULL
6806 || DECL_INITIAL (exp) == error_mark_node))
6807 local_p = false;
6808 /* Otherwise we're left with initialized (or non-common) global data
6809 which is of necessity defined locally. */
6810 else
6811 local_p = true;
6813 return local_p;
6816 /* Return true when references to DECL must bind to current definition in
6817 final executable.
6819 The condition is usually equivalent to whether the function binds to the
6820 current module (shared library or executable), that is to binds_local_p.
6821 We use this fact to avoid need for another target hook and implement
6822 the logic using binds_local_p and just special cases where
6823 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
6824 the weak definitions (that can be overwritten at linktime by other
6825 definition from different object file) and when resolution info is available
6826 we simply use the knowledge passed to us by linker plugin. */
6827 bool
6828 decl_binds_to_current_def_p (tree decl)
6830 gcc_assert (DECL_P (decl));
6831 if (!targetm.binds_local_p (decl))
6832 return false;
6833 if (!TREE_PUBLIC (decl))
6834 return true;
6835 /* When resolution is available, just use it. */
6836 if (TREE_CODE (decl) == VAR_DECL
6837 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl)))
6839 varpool_node *vnode = varpool_get_node (decl);
6840 if (vnode
6841 && vnode->resolution != LDPR_UNKNOWN)
6842 return resolution_to_local_definition_p (vnode->resolution);
6844 else if (TREE_CODE (decl) == FUNCTION_DECL)
6846 struct cgraph_node *node = cgraph_get_node (decl);
6847 if (node
6848 && node->resolution != LDPR_UNKNOWN)
6849 return resolution_to_local_definition_p (node->resolution);
6851 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
6852 binds locally but still can be overwritten), DECL_COMMON (can be merged
6853 with a non-common definition somewhere in the same module) or
6854 DECL_EXTERNAL.
6855 This rely on fact that binds_local_p behave as decl_replaceable_p
6856 for all other declaration types. */
6857 if (DECL_WEAK (decl))
6858 return false;
6859 if (DECL_COMMON (decl)
6860 && (DECL_INITIAL (decl) == NULL
6861 || DECL_INITIAL (decl) == error_mark_node))
6862 return false;
6863 if (DECL_EXTERNAL (decl))
6864 return false;
6865 return true;
6868 /* A replaceable function or variable is one which may be replaced
6869 at link-time with an entirely different definition, provided that the
6870 replacement has the same type. For example, functions declared
6871 with __attribute__((weak)) on most systems are replaceable.
6873 COMDAT functions are not replaceable, since all definitions of the
6874 function must be equivalent. It is important that COMDAT functions
6875 not be treated as replaceable so that use of C++ template
6876 instantiations is not penalized. */
6878 bool
6879 decl_replaceable_p (tree decl)
6881 gcc_assert (DECL_P (decl));
6882 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
6883 return false;
6884 return !decl_binds_to_current_def_p (decl);
6887 /* Default function to output code that will globalize a label. A
6888 target must define GLOBAL_ASM_OP or provide its own function to
6889 globalize a label. */
6890 #ifdef GLOBAL_ASM_OP
6891 void
6892 default_globalize_label (FILE * stream, const char *name)
6894 fputs (GLOBAL_ASM_OP, stream);
6895 assemble_name (stream, name);
6896 putc ('\n', stream);
6898 #endif /* GLOBAL_ASM_OP */
6900 /* Default function to output code that will globalize a declaration. */
6901 void
6902 default_globalize_decl_name (FILE * stream, tree decl)
6904 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
6905 targetm.asm_out.globalize_label (stream, name);
6908 /* Default function to output a label for unwind information. The
6909 default is to do nothing. A target that needs nonlocal labels for
6910 unwind information must provide its own function to do this. */
6911 void
6912 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
6913 tree decl ATTRIBUTE_UNUSED,
6914 int for_eh ATTRIBUTE_UNUSED,
6915 int empty ATTRIBUTE_UNUSED)
6919 /* Default function to output a label to divide up the exception table.
6920 The default is to do nothing. A target that needs/wants to divide
6921 up the table must provide it's own function to do this. */
6922 void
6923 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
6927 /* This is how to output an internal numbered label where PREFIX is
6928 the class of label and LABELNO is the number within the class. */
6930 void
6931 default_generate_internal_label (char *buf, const char *prefix,
6932 unsigned long labelno)
6934 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6937 /* This is how to output an internal numbered label where PREFIX is
6938 the class of label and LABELNO is the number within the class. */
6940 void
6941 default_internal_label (FILE *stream, const char *prefix,
6942 unsigned long labelno)
6944 char *const buf = (char *) alloca (40 + strlen (prefix));
6945 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6946 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
6950 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
6952 void
6953 default_asm_declare_constant_name (FILE *file, const char *name,
6954 const_tree exp ATTRIBUTE_UNUSED,
6955 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
6957 assemble_label (file, name);
6960 /* This is the default behavior at the beginning of a file. It's
6961 controlled by two other target-hook toggles. */
6962 void
6963 default_file_start (void)
6965 if (targetm.asm_file_start_app_off
6966 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
6967 fputs (ASM_APP_OFF, asm_out_file);
6969 if (targetm.asm_file_start_file_directive)
6970 output_file_directive (asm_out_file, main_input_filename);
6973 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
6974 which emits a special section directive used to indicate whether or
6975 not this object file needs an executable stack. This is primarily
6976 a GNU extension to ELF but could be used on other targets. */
6978 int trampolines_created;
6980 void
6981 file_end_indicate_exec_stack (void)
6983 unsigned int flags = SECTION_DEBUG;
6984 if (trampolines_created)
6985 flags |= SECTION_CODE;
6987 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
6990 /* Emit a special section directive to indicate that this object file
6991 was compiled with -fsplit-stack. This is used to let the linker
6992 detect calls between split-stack code and non-split-stack code, so
6993 that it can modify the split-stack code to allocate a sufficiently
6994 large stack. We emit another special section if there are any
6995 functions in this file which have the no_split_stack attribute, to
6996 prevent the linker from warning about being unable to convert the
6997 functions if they call non-split-stack code. */
6999 void
7000 file_end_indicate_split_stack (void)
7002 if (flag_split_stack)
7004 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
7005 NULL));
7006 if (saw_no_split_stack)
7007 switch_to_section (get_section (".note.GNU-no-split-stack",
7008 SECTION_DEBUG, NULL));
7012 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
7013 a get_unnamed_section callback. */
7015 void
7016 output_section_asm_op (const void *directive)
7018 fprintf (asm_out_file, "%s\n", (const char *) directive);
7021 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
7022 the current section is NEW_SECTION. */
7024 void
7025 switch_to_section (section *new_section)
7027 if (in_section == new_section)
7028 return;
7030 if (new_section->common.flags & SECTION_FORGET)
7031 in_section = NULL;
7032 else
7033 in_section = new_section;
7035 switch (SECTION_STYLE (new_section))
7037 case SECTION_NAMED:
7038 targetm.asm_out.named_section (new_section->named.name,
7039 new_section->named.common.flags,
7040 new_section->named.decl);
7041 break;
7043 case SECTION_UNNAMED:
7044 new_section->unnamed.callback (new_section->unnamed.data);
7045 break;
7047 case SECTION_NOSWITCH:
7048 gcc_unreachable ();
7049 break;
7052 new_section->common.flags |= SECTION_DECLARED;
7055 /* If block symbol SYMBOL has not yet been assigned an offset, place
7056 it at the end of its block. */
7058 void
7059 place_block_symbol (rtx symbol)
7061 unsigned HOST_WIDE_INT size, mask, offset;
7062 struct constant_descriptor_rtx *desc;
7063 unsigned int alignment;
7064 struct object_block *block;
7065 tree decl;
7067 gcc_assert (SYMBOL_REF_BLOCK (symbol));
7068 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7069 return;
7071 /* Work out the symbol's size and alignment. */
7072 if (CONSTANT_POOL_ADDRESS_P (symbol))
7074 desc = SYMBOL_REF_CONSTANT (symbol);
7075 alignment = desc->align;
7076 size = GET_MODE_SIZE (desc->mode);
7078 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7080 decl = SYMBOL_REF_DECL (symbol);
7081 alignment = DECL_ALIGN (decl);
7082 size = get_constant_size (DECL_INITIAL (decl));
7083 if ((flag_sanitize & SANITIZE_ADDRESS)
7084 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7085 && asan_protect_global (DECL_INITIAL (decl)))
7086 size += asan_red_zone_size (size);
7088 else
7090 struct symtab_node *snode;
7091 decl = SYMBOL_REF_DECL (symbol);
7093 snode = symtab_get_node (decl);
7094 if (snode->alias)
7096 rtx target = DECL_RTL (symtab_alias_ultimate_target (snode)->decl);
7097 SYMBOL_REF_BLOCK_OFFSET (symbol) = SYMBOL_REF_BLOCK_OFFSET (target);
7098 return;
7100 alignment = get_variable_align (decl);
7101 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7102 if ((flag_sanitize & SANITIZE_ADDRESS)
7103 && asan_protect_global (decl))
7105 size += asan_red_zone_size (size);
7106 alignment = MAX (alignment,
7107 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7111 /* Calculate the object's offset from the start of the block. */
7112 block = SYMBOL_REF_BLOCK (symbol);
7113 mask = alignment / BITS_PER_UNIT - 1;
7114 offset = (block->size + mask) & ~mask;
7115 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7117 /* Record the block's new alignment and size. */
7118 block->alignment = MAX (block->alignment, alignment);
7119 block->size = offset + size;
7121 vec_safe_push (block->objects, symbol);
7124 /* Return the anchor that should be used to address byte offset OFFSET
7125 from the first object in BLOCK. MODEL is the TLS model used
7126 to access it. */
7129 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7130 enum tls_model model)
7132 char label[100];
7133 unsigned int begin, middle, end;
7134 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7135 rtx anchor;
7137 /* Work out the anchor's offset. Use an offset of 0 for the first
7138 anchor so that we don't pessimize the case where we take the address
7139 of a variable at the beginning of the block. This is particularly
7140 useful when a block has only one variable assigned to it.
7142 We try to place anchors RANGE bytes apart, so there can then be
7143 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7144 a ptr_mode offset. With some target settings, the lowest such
7145 anchor might be out of range for the lowest ptr_mode offset;
7146 likewise the highest anchor for the highest offset. Use anchors
7147 at the extreme ends of the ptr_mode range in such cases.
7149 All arithmetic uses unsigned integers in order to avoid
7150 signed overflow. */
7151 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7152 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7153 range = max_offset - min_offset + 1;
7154 if (range == 0)
7155 offset = 0;
7156 else
7158 bias = 1 << (GET_MODE_BITSIZE (ptr_mode) - 1);
7159 if (offset < 0)
7161 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7162 delta -= delta % range;
7163 if (delta > bias)
7164 delta = bias;
7165 offset = (HOST_WIDE_INT) (-delta);
7167 else
7169 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7170 delta -= delta % range;
7171 if (delta > bias - 1)
7172 delta = bias - 1;
7173 offset = (HOST_WIDE_INT) delta;
7177 /* Do a binary search to see if there's already an anchor we can use.
7178 Set BEGIN to the new anchor's index if not. */
7179 begin = 0;
7180 end = vec_safe_length (block->anchors);
7181 while (begin != end)
7183 middle = (end + begin) / 2;
7184 anchor = (*block->anchors)[middle];
7185 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7186 end = middle;
7187 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7188 begin = middle + 1;
7189 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7190 end = middle;
7191 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7192 begin = middle + 1;
7193 else
7194 return anchor;
7197 /* Create a new anchor with a unique label. */
7198 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7199 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7200 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7201 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7203 /* Insert it at index BEGIN. */
7204 vec_safe_insert (block->anchors, begin, anchor);
7205 return anchor;
7208 /* Output the objects in BLOCK. */
7210 static void
7211 output_object_block (struct object_block *block)
7213 struct constant_descriptor_rtx *desc;
7214 unsigned int i;
7215 HOST_WIDE_INT offset;
7216 tree decl;
7217 rtx symbol;
7219 if (!block->objects)
7220 return;
7222 /* Switch to the section and make sure that the first byte is
7223 suitably aligned. */
7224 switch_to_section (block->sect);
7225 assemble_align (block->alignment);
7227 /* Define the values of all anchors relative to the current section
7228 position. */
7229 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7230 targetm.asm_out.output_anchor (symbol);
7232 /* Output the objects themselves. */
7233 offset = 0;
7234 FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7236 /* Move to the object's offset, padding with zeros if necessary. */
7237 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7238 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7239 if (CONSTANT_POOL_ADDRESS_P (symbol))
7241 desc = SYMBOL_REF_CONSTANT (symbol);
7242 output_constant_pool_1 (desc, 1);
7243 offset += GET_MODE_SIZE (desc->mode);
7245 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7247 HOST_WIDE_INT size;
7248 decl = SYMBOL_REF_DECL (symbol);
7249 assemble_constant_contents (DECL_INITIAL (decl), XSTR (symbol, 0),
7250 DECL_ALIGN (decl));
7251 size = get_constant_size (DECL_INITIAL (decl));
7252 offset += size;
7253 if ((flag_sanitize & SANITIZE_ADDRESS)
7254 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7255 && asan_protect_global (DECL_INITIAL (decl)))
7257 size = asan_red_zone_size (size);
7258 assemble_zeros (size);
7259 offset += size;
7262 else
7264 HOST_WIDE_INT size;
7265 decl = SYMBOL_REF_DECL (symbol);
7266 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7267 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7268 offset += size;
7269 if ((flag_sanitize & SANITIZE_ADDRESS)
7270 && asan_protect_global (decl))
7272 size = asan_red_zone_size (size);
7273 assemble_zeros (size);
7274 offset += size;
7280 /* A htab_traverse callback used to call output_object_block for
7281 each member of object_block_htab. */
7283 static int
7284 output_object_block_htab (void **slot, void *data ATTRIBUTE_UNUSED)
7286 output_object_block ((struct object_block *) (*slot));
7287 return 1;
7290 /* Output the definitions of all object_blocks. */
7292 void
7293 output_object_blocks (void)
7295 htab_traverse (object_block_htab, output_object_block_htab, NULL);
7298 /* This function provides a possible implementation of the
7299 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7300 by -frecord-gcc-switches it creates a new mergeable, string section in the
7301 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7302 contains the switches in ASCII format.
7304 FIXME: This code does not correctly handle double quote characters
7305 that appear inside strings, (it strips them rather than preserving them).
7306 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7307 characters - instead it treats them as sub-string separators. Since
7308 we want to emit NUL strings terminators into the object file we have to use
7309 ASM_OUTPUT_SKIP. */
7312 elf_record_gcc_switches (print_switch_type type, const char * name)
7314 switch (type)
7316 case SWITCH_TYPE_PASSED:
7317 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7318 ASM_OUTPUT_SKIP (asm_out_file, (unsigned HOST_WIDE_INT) 1);
7319 break;
7321 case SWITCH_TYPE_DESCRIPTIVE:
7322 if (name == NULL)
7324 /* Distinguish between invocations where name is NULL. */
7325 static bool started = false;
7327 if (!started)
7329 section * sec;
7331 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7332 SECTION_DEBUG
7333 | SECTION_MERGE
7334 | SECTION_STRINGS
7335 | (SECTION_ENTSIZE & 1),
7336 NULL);
7337 switch_to_section (sec);
7338 started = true;
7342 default:
7343 break;
7346 /* The return value is currently ignored by the caller, but must be 0.
7347 For -fverbose-asm the return value would be the number of characters
7348 emitted into the assembler file. */
7349 return 0;
7352 /* Emit text to declare externally defined symbols. It is needed to
7353 properly support non-default visibility. */
7354 void
7355 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7356 tree decl,
7357 const char *name ATTRIBUTE_UNUSED)
7359 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7360 set in order to avoid putting out names that are never really
7361 used. */
7362 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7363 && targetm.binds_local_p (decl))
7364 maybe_assemble_visibility (decl);
7367 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7369 void
7370 default_asm_output_source_filename (FILE *file, const char *name)
7372 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7373 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7374 #else
7375 fprintf (file, "\t.file\t");
7376 output_quoted_string (file, name);
7377 putc ('\n', file);
7378 #endif
7381 /* Output a file name in the form wanted by System V. */
7383 void
7384 output_file_directive (FILE *asm_file, const char *input_name)
7386 int len;
7387 const char *na;
7389 if (input_name == NULL)
7390 input_name = "<stdin>";
7391 else
7392 input_name = remap_debug_filename (input_name);
7394 len = strlen (input_name);
7395 na = input_name + len;
7397 /* NA gets INPUT_NAME sans directory names. */
7398 while (na > input_name)
7400 if (IS_DIR_SEPARATOR (na[-1]))
7401 break;
7402 na--;
7405 targetm.asm_out.output_source_filename (asm_file, na);
7408 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7409 EXP. */
7411 make_debug_expr_from_rtl (const_rtx exp)
7413 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7414 enum machine_mode mode = GET_MODE (exp);
7415 rtx dval;
7417 DECL_ARTIFICIAL (ddecl) = 1;
7418 if (REG_P (exp) && REG_EXPR (exp))
7419 type = TREE_TYPE (REG_EXPR (exp));
7420 else if (MEM_P (exp) && MEM_EXPR (exp))
7421 type = TREE_TYPE (MEM_EXPR (exp));
7422 else
7423 type = NULL_TREE;
7424 if (type && TYPE_MODE (type) == mode)
7425 TREE_TYPE (ddecl) = type;
7426 else
7427 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7428 DECL_MODE (ddecl) = mode;
7429 dval = gen_rtx_DEBUG_EXPR (mode);
7430 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7431 SET_DECL_RTL (ddecl, dval);
7432 return dval;
7435 #ifdef ELF_ASCII_ESCAPES
7436 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7438 void
7439 default_elf_asm_output_limited_string (FILE *f, const char *s)
7441 int escape;
7442 unsigned char c;
7444 fputs (STRING_ASM_OP, f);
7445 putc ('"', f);
7446 while (*s != '\0')
7448 c = *s;
7449 escape = ELF_ASCII_ESCAPES[c];
7450 switch (escape)
7452 case 0:
7453 putc (c, f);
7454 break;
7455 case 1:
7456 /* TODO: Print in hex with fast function, important for -flto. */
7457 fprintf (f, "\\%03o", c);
7458 break;
7459 default:
7460 putc ('\\', f);
7461 putc (escape, f);
7462 break;
7464 s++;
7466 putc ('\"', f);
7467 putc ('\n', f);
7470 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7472 void
7473 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7475 const char *limit = s + len;
7476 const char *last_null = NULL;
7477 unsigned bytes_in_chunk = 0;
7478 unsigned char c;
7479 int escape;
7481 for (; s < limit; s++)
7483 const char *p;
7485 if (bytes_in_chunk >= 60)
7487 putc ('\"', f);
7488 putc ('\n', f);
7489 bytes_in_chunk = 0;
7492 if (s > last_null)
7494 for (p = s; p < limit && *p != '\0'; p++)
7495 continue;
7496 last_null = p;
7498 else
7499 p = last_null;
7501 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7503 if (bytes_in_chunk > 0)
7505 putc ('\"', f);
7506 putc ('\n', f);
7507 bytes_in_chunk = 0;
7510 default_elf_asm_output_limited_string (f, s);
7511 s = p;
7513 else
7515 if (bytes_in_chunk == 0)
7516 fputs (ASCII_DATA_ASM_OP "\"", f);
7518 c = *s;
7519 escape = ELF_ASCII_ESCAPES[c];
7520 switch (escape)
7522 case 0:
7523 putc (c, f);
7524 bytes_in_chunk++;
7525 break;
7526 case 1:
7527 /* TODO: Print in hex with fast function, important for -flto. */
7528 fprintf (f, "\\%03o", c);
7529 bytes_in_chunk += 4;
7530 break;
7531 default:
7532 putc ('\\', f);
7533 putc (escape, f);
7534 bytes_in_chunk += 2;
7535 break;
7541 if (bytes_in_chunk > 0)
7543 putc ('\"', f);
7544 putc ('\n', f);
7547 #endif
7549 static GTY(()) section *elf_init_array_section;
7550 static GTY(()) section *elf_fini_array_section;
7552 static section *
7553 get_elf_initfini_array_priority_section (int priority,
7554 bool constructor_p)
7556 section *sec;
7557 if (priority != DEFAULT_INIT_PRIORITY)
7559 char buf[18];
7560 sprintf (buf, "%s.%.5u",
7561 constructor_p ? ".init_array" : ".fini_array",
7562 priority);
7563 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7565 else
7567 if (constructor_p)
7569 if (elf_init_array_section == NULL)
7570 elf_init_array_section
7571 = get_section (".init_array",
7572 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7573 sec = elf_init_array_section;
7575 else
7577 if (elf_fini_array_section == NULL)
7578 elf_fini_array_section
7579 = get_section (".fini_array",
7580 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7581 sec = elf_fini_array_section;
7584 return sec;
7587 /* Use .init_array section for constructors. */
7589 void
7590 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7592 section *sec = get_elf_initfini_array_priority_section (priority,
7593 true);
7594 assemble_addr_to_section (symbol, sec);
7597 /* Use .fini_array section for destructors. */
7599 void
7600 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7602 section *sec = get_elf_initfini_array_priority_section (priority,
7603 false);
7604 assemble_addr_to_section (symbol, sec);
7607 /* Default TARGET_ASM_OUTPUT_IDENT hook.
7609 This is a bit of a cheat. The real default is a no-op, but this
7610 hook is the default for all targets with a .ident directive. */
7612 void
7613 default_asm_output_ident_directive (const char *ident_str)
7615 const char *ident_asm_op = "\t.ident\t";
7617 /* If we are still in the front end, do not write out the string
7618 to asm_out_file. Instead, add a fake top-level asm statement.
7619 This allows the front ends to use this hook without actually
7620 writing to asm_out_file, to handle #ident or Pragma Ident. */
7621 if (cgraph_state == CGRAPH_STATE_PARSING)
7623 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
7624 add_asm_node (build_string (strlen (buf), buf));
7626 else
7627 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
7630 #include "gt-varasm.h"