* doc/extend.texi (Size of an asm): Really move node to its position.
[official-gcc.git] / gcc / varasm.c
blob988665260cc4f40f94fa04ce8e32b5e8f7e38fd2
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_ONE_ONLY (decl)))
433 targetm.asm_out.unique_section (decl, reloc);
434 DECL_HAS_IMPLICIT_SECTION_NAME_P (decl) = true;
438 #ifdef BSS_SECTION_ASM_OP
440 #ifdef ASM_OUTPUT_ALIGNED_BSS
442 /* Utility function for targets to use in implementing
443 ASM_OUTPUT_ALIGNED_BSS.
444 ??? It is believed that this function will work in most cases so such
445 support is localized here. */
447 static void
448 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
449 const char *name, unsigned HOST_WIDE_INT size,
450 int align)
452 switch_to_section (bss_section);
453 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
454 #ifdef ASM_DECLARE_OBJECT_NAME
455 last_assemble_variable_decl = decl;
456 ASM_DECLARE_OBJECT_NAME (file, name, decl);
457 #else
458 /* Standard thing is just output label for the object. */
459 ASM_OUTPUT_LABEL (file, name);
460 #endif /* ASM_DECLARE_OBJECT_NAME */
461 ASM_OUTPUT_SKIP (file, size ? size : 1);
464 #endif
466 #endif /* BSS_SECTION_ASM_OP */
468 #ifndef USE_SELECT_SECTION_FOR_FUNCTIONS
469 /* Return the hot section for function DECL. Return text_section for
470 null DECLs. */
472 static section *
473 hot_function_section (tree decl)
475 if (decl != NULL_TREE
476 && DECL_SECTION_NAME (decl) != NULL_TREE
477 && targetm_common.have_named_sections)
478 return get_named_section (decl, NULL, 0);
479 else
480 return text_section;
482 #endif
484 /* Return section for TEXT_SECTION_NAME if DECL or DECL_SECTION_NAME (DECL)
485 is NULL.
487 When DECL_SECTION_NAME is non-NULL and it is implicit section and
488 NAMED_SECTION_SUFFIX is non-NULL, then produce section called
489 concatenate the name with NAMED_SECTION_SUFFIX.
490 Otherwise produce "TEXT_SECTION_NAME.IMPLICIT_NAME". */
492 section *
493 get_named_text_section (tree decl,
494 const char *text_section_name,
495 const char *named_section_suffix)
497 if (decl && DECL_SECTION_NAME (decl))
499 if (named_section_suffix)
501 tree dsn = DECL_SECTION_NAME (decl);
502 const char *stripped_name;
503 char *name, *buffer;
505 name = (char *) alloca (TREE_STRING_LENGTH (dsn) + 1);
506 memcpy (name, TREE_STRING_POINTER (dsn),
507 TREE_STRING_LENGTH (dsn) + 1);
509 stripped_name = targetm.strip_name_encoding (name);
511 buffer = ACONCAT ((stripped_name, named_section_suffix, NULL));
512 return get_named_section (decl, buffer, 0);
514 else if (DECL_HAS_IMPLICIT_SECTION_NAME_P (decl))
516 const char *name;
518 /* Do not try to split gnu_linkonce functions. This gets somewhat
519 slipperly. */
520 if (DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP)
521 return NULL;
522 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
523 name = targetm.strip_name_encoding (name);
524 return get_named_section (decl, ACONCAT ((text_section_name, ".",
525 name, NULL)), 0);
527 else
528 return NULL;
530 return get_named_section (decl, text_section_name, 0);
533 /* Choose named function section based on its frequency. */
535 section *
536 default_function_section (tree decl, enum node_frequency freq,
537 bool startup, bool exit)
539 #if defined HAVE_LD_EH_GC_SECTIONS && defined HAVE_LD_EH_GC_SECTIONS_BUG
540 /* Old GNU linkers have buggy --gc-section support, which sometimes
541 results in .gcc_except_table* sections being garbage collected. */
542 if (decl
543 && DECL_SECTION_NAME (decl)
544 && DECL_HAS_IMPLICIT_SECTION_NAME_P (decl))
545 return NULL;
546 #endif
548 if (!flag_reorder_functions
549 || !targetm_common.have_named_sections)
550 return NULL;
551 /* Startup code should go to startup subsection unless it is
552 unlikely executed (this happens especially with function splitting
553 where we can split away unnecessary parts of static constructors. */
554 if (startup && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
556 /* If we do have a profile or(and) LTO phase is executed, we do not need
557 these ELF section. */
558 if (!in_lto_p || !flag_profile_values)
559 return get_named_text_section (decl, ".text.startup", NULL);
560 else
561 return NULL;
564 /* Similarly for exit. */
565 if (exit && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
566 return get_named_text_section (decl, ".text.exit", NULL);
568 /* Group cold functions together, similarly for hot code. */
569 switch (freq)
571 case NODE_FREQUENCY_UNLIKELY_EXECUTED:
572 return get_named_text_section (decl, ".text.unlikely", NULL);
573 case NODE_FREQUENCY_HOT:
574 /* If we do have a profile or(and) LTO phase is executed, we do not need
575 these ELF section. */
576 if (!in_lto_p || !flag_profile_values)
577 return get_named_text_section (decl, ".text.hot", NULL);
578 default:
579 return NULL;
583 /* Return the section for function DECL.
585 If DECL is NULL_TREE, return the text section. We can be passed
586 NULL_TREE under some circumstances by dbxout.c at least.
588 If FORCE_COLD is true, return cold function section ignoring
589 the frequency info of cgraph_node. */
591 static section *
592 function_section_1 (tree decl, bool force_cold)
594 section *section = NULL;
595 enum node_frequency freq = NODE_FREQUENCY_NORMAL;
596 bool startup = false, exit = false;
598 if (decl)
600 struct cgraph_node *node = cgraph_get_node (decl);
602 if (node)
604 freq = node->frequency;
605 startup = node->only_called_at_startup;
606 exit = node->only_called_at_exit;
609 if (force_cold)
610 freq = NODE_FREQUENCY_UNLIKELY_EXECUTED;
612 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
613 if (decl != NULL_TREE
614 && DECL_SECTION_NAME (decl) != NULL_TREE)
616 if (targetm.asm_out.function_section)
617 section = targetm.asm_out.function_section (decl, freq,
618 startup, exit);
619 if (section)
620 return section;
621 return get_named_section (decl, NULL, 0);
623 else
624 return targetm.asm_out.select_section
625 (decl, freq == NODE_FREQUENCY_UNLIKELY_EXECUTED,
626 DECL_ALIGN (decl));
627 #else
628 if (targetm.asm_out.function_section)
629 section = targetm.asm_out.function_section (decl, freq, startup, exit);
630 if (section)
631 return section;
632 return hot_function_section (decl);
633 #endif
636 /* Return the section for function DECL.
638 If DECL is NULL_TREE, return the text section. We can be passed
639 NULL_TREE under some circumstances by dbxout.c at least. */
641 section *
642 function_section (tree decl)
644 /* Handle cases where function splitting code decides
645 to put function entry point into unlikely executed section
646 despite the fact that the function itself is not cold
647 (i.e. it is called rarely but contains a hot loop that is
648 better to live in hot subsection for the code locality). */
649 return function_section_1 (decl,
650 first_function_block_is_cold);
653 /* Return the section for the current function, take IN_COLD_SECTION_P
654 into account. */
656 section *
657 current_function_section (void)
659 return function_section_1 (current_function_decl, in_cold_section_p);
662 /* Tell assembler to switch to unlikely-to-be-executed text section. */
664 section *
665 unlikely_text_section (void)
667 return function_section_1 (current_function_decl, true);
670 /* When called within a function context, return true if the function
671 has been assigned a cold text section and if SECT is that section.
672 When called outside a function context, return true if SECT is the
673 default cold section. */
675 bool
676 unlikely_text_section_p (section *sect)
678 return sect == function_section_1 (current_function_decl, true);
681 /* Return the read-only data section associated with function DECL. */
683 section *
684 default_function_rodata_section (tree decl)
686 if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
688 const char *name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
690 if (DECL_ONE_ONLY (decl) && HAVE_COMDAT_GROUP)
692 const char *dot;
693 size_t len;
694 char* rname;
696 dot = strchr (name + 1, '.');
697 if (!dot)
698 dot = name;
699 len = strlen (dot) + 8;
700 rname = (char *) alloca (len);
702 strcpy (rname, ".rodata");
703 strcat (rname, dot);
704 return get_section (rname, SECTION_LINKONCE, decl);
706 /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo. */
707 else if (DECL_ONE_ONLY (decl)
708 && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
710 size_t len = strlen (name) + 1;
711 char *rname = (char *) alloca (len);
713 memcpy (rname, name, len);
714 rname[14] = 'r';
715 return get_section (rname, SECTION_LINKONCE, decl);
717 /* For .text.foo we want to use .rodata.foo. */
718 else if (flag_function_sections && flag_data_sections
719 && strncmp (name, ".text.", 6) == 0)
721 size_t len = strlen (name) + 1;
722 char *rname = (char *) alloca (len + 2);
724 memcpy (rname, ".rodata", 7);
725 memcpy (rname + 7, name + 5, len - 5);
726 return get_section (rname, 0, decl);
730 return readonly_data_section;
733 /* Return the read-only data section associated with function DECL
734 for targets where that section should be always the single
735 readonly data section. */
737 section *
738 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
740 return readonly_data_section;
743 /* Return the section to use for string merging. */
745 static section *
746 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
747 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
748 unsigned int flags ATTRIBUTE_UNUSED)
750 HOST_WIDE_INT len;
752 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
753 && TREE_CODE (decl) == STRING_CST
754 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
755 && align <= 256
756 && (len = int_size_in_bytes (TREE_TYPE (decl))) > 0
757 && TREE_STRING_LENGTH (decl) >= len)
759 enum machine_mode mode;
760 unsigned int modesize;
761 const char *str;
762 HOST_WIDE_INT i;
763 int j, unit;
764 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
765 char *name = (char *) alloca (strlen (prefix) + 30);
767 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
768 modesize = GET_MODE_BITSIZE (mode);
769 if (modesize >= 8 && modesize <= 256
770 && (modesize & (modesize - 1)) == 0)
772 if (align < modesize)
773 align = modesize;
775 str = TREE_STRING_POINTER (decl);
776 unit = GET_MODE_SIZE (mode);
778 /* Check for embedded NUL characters. */
779 for (i = 0; i < len; i += unit)
781 for (j = 0; j < unit; j++)
782 if (str[i + j] != '\0')
783 break;
784 if (j == unit)
785 break;
787 if (i == len - unit)
789 sprintf (name, "%s.str%d.%d", prefix,
790 modesize / 8, (int) (align / 8));
791 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
792 return get_section (name, flags, NULL);
797 return readonly_data_section;
800 /* Return the section to use for constant merging. */
802 section *
803 mergeable_constant_section (enum machine_mode mode ATTRIBUTE_UNUSED,
804 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
805 unsigned int flags ATTRIBUTE_UNUSED)
807 unsigned int modesize = GET_MODE_BITSIZE (mode);
809 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
810 && mode != VOIDmode
811 && mode != BLKmode
812 && modesize <= align
813 && align >= 8
814 && align <= 256
815 && (align & (align - 1)) == 0)
817 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
818 char *name = (char *) alloca (strlen (prefix) + 30);
820 sprintf (name, "%s.cst%d", prefix, (int) (align / 8));
821 flags |= (align / 8) | SECTION_MERGE;
822 return get_section (name, flags, NULL);
824 return readonly_data_section;
827 /* Given NAME, a putative register name, discard any customary prefixes. */
829 static const char *
830 strip_reg_name (const char *name)
832 #ifdef REGISTER_PREFIX
833 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
834 name += strlen (REGISTER_PREFIX);
835 #endif
836 if (name[0] == '%' || name[0] == '#')
837 name++;
838 return name;
841 /* The user has asked for a DECL to have a particular name. Set (or
842 change) it in such a way that we don't prefix an underscore to
843 it. */
844 void
845 set_user_assembler_name (tree decl, const char *name)
847 char *starred = (char *) alloca (strlen (name) + 2);
848 starred[0] = '*';
849 strcpy (starred + 1, name);
850 change_decl_assembler_name (decl, get_identifier (starred));
851 SET_DECL_RTL (decl, NULL_RTX);
854 /* Decode an `asm' spec for a declaration as a register name.
855 Return the register number, or -1 if nothing specified,
856 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
857 or -3 if ASMSPEC is `cc' and is not recognized,
858 or -4 if ASMSPEC is `memory' and is not recognized.
859 Accept an exact spelling or a decimal number.
860 Prefixes such as % are optional. */
863 decode_reg_name_and_count (const char *asmspec, int *pnregs)
865 /* Presume just one register is clobbered. */
866 *pnregs = 1;
868 if (asmspec != 0)
870 int i;
872 /* Get rid of confusing prefixes. */
873 asmspec = strip_reg_name (asmspec);
875 /* Allow a decimal number as a "register name". */
876 for (i = strlen (asmspec) - 1; i >= 0; i--)
877 if (! ISDIGIT (asmspec[i]))
878 break;
879 if (asmspec[0] != 0 && i < 0)
881 i = atoi (asmspec);
882 if (i < FIRST_PSEUDO_REGISTER && i >= 0)
883 return i;
884 else
885 return -2;
888 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
889 if (reg_names[i][0]
890 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
891 return i;
893 #ifdef OVERLAPPING_REGISTER_NAMES
895 static const struct
897 const char *const name;
898 const int number;
899 const int nregs;
900 } table[] = OVERLAPPING_REGISTER_NAMES;
902 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
903 if (table[i].name[0]
904 && ! strcmp (asmspec, table[i].name))
906 *pnregs = table[i].nregs;
907 return table[i].number;
910 #endif /* OVERLAPPING_REGISTER_NAMES */
912 #ifdef ADDITIONAL_REGISTER_NAMES
914 static const struct { const char *const name; const int number; } table[]
915 = ADDITIONAL_REGISTER_NAMES;
917 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
918 if (table[i].name[0]
919 && ! strcmp (asmspec, table[i].name))
920 return table[i].number;
922 #endif /* ADDITIONAL_REGISTER_NAMES */
924 if (!strcmp (asmspec, "memory"))
925 return -4;
927 if (!strcmp (asmspec, "cc"))
928 return -3;
930 return -2;
933 return -1;
937 decode_reg_name (const char *name)
939 int count;
940 return decode_reg_name_and_count (name, &count);
944 /* Return true if DECL's initializer is suitable for a BSS section. */
946 bool
947 bss_initializer_p (const_tree decl)
949 return (DECL_INITIAL (decl) == NULL
950 || DECL_INITIAL (decl) == error_mark_node
951 || (flag_zero_initialized_in_bss
952 /* Leave constant zeroes in .rodata so they
953 can be shared. */
954 && !TREE_READONLY (decl)
955 && initializer_zerop (DECL_INITIAL (decl))));
958 /* Compute the alignment of variable specified by DECL.
959 DONT_OUTPUT_DATA is from assemble_variable. */
961 void
962 align_variable (tree decl, bool dont_output_data)
964 unsigned int align = DECL_ALIGN (decl);
966 /* In the case for initialing an array whose length isn't specified,
967 where we have not yet been able to do the layout,
968 figure out the proper alignment now. */
969 if (dont_output_data && DECL_SIZE (decl) == 0
970 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
971 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
973 /* Some object file formats have a maximum alignment which they support.
974 In particular, a.out format supports a maximum alignment of 4. */
975 if (align > MAX_OFILE_ALIGNMENT)
977 error ("alignment of %q+D is greater than maximum object "
978 "file alignment %d", decl,
979 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
980 align = MAX_OFILE_ALIGNMENT;
983 if (! DECL_USER_ALIGN (decl))
985 #ifdef DATA_ABI_ALIGNMENT
986 unsigned int data_abi_align
987 = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
988 /* For backwards compatibility, don't assume the ABI alignment for
989 TLS variables. */
990 if (! DECL_THREAD_LOCAL_P (decl) || data_abi_align <= BITS_PER_WORD)
991 align = data_abi_align;
992 #endif
994 /* On some machines, it is good to increase alignment sometimes.
995 But as DECL_ALIGN is used both for actually emitting the variable
996 and for code accessing the variable as guaranteed alignment, we
997 can only increase the alignment if it is a performance optimization
998 if the references to it must bind to the current definition. */
999 if (decl_binds_to_current_def_p (decl))
1001 #ifdef DATA_ALIGNMENT
1002 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1003 /* Don't increase alignment too much for TLS variables - TLS space
1004 is too precious. */
1005 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1006 align = data_align;
1007 #endif
1008 #ifdef CONSTANT_ALIGNMENT
1009 if (DECL_INITIAL (decl) != 0
1010 && DECL_INITIAL (decl) != error_mark_node)
1012 unsigned int const_align
1013 = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
1014 /* Don't increase alignment too much for TLS variables - TLS
1015 space is too precious. */
1016 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1017 align = const_align;
1019 #endif
1023 /* Reset the alignment in case we have made it tighter, so we can benefit
1024 from it in get_pointer_alignment. */
1025 DECL_ALIGN (decl) = align;
1028 /* Return DECL_ALIGN (decl), possibly increased for optimization purposes
1029 beyond what align_variable returned. */
1031 static unsigned int
1032 get_variable_align (tree decl)
1034 unsigned int align = DECL_ALIGN (decl);
1036 /* For user aligned vars or static vars align_variable already did
1037 everything. */
1038 if (DECL_USER_ALIGN (decl) || !TREE_PUBLIC (decl))
1039 return align;
1041 #ifdef DATA_ABI_ALIGNMENT
1042 if (DECL_THREAD_LOCAL_P (decl))
1043 align = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1044 #endif
1046 /* For decls that bind to the current definition, align_variable
1047 did also everything, except for not assuming ABI required alignment
1048 of TLS variables. For other vars, increase the alignment here
1049 as an optimization. */
1050 if (!decl_binds_to_current_def_p (decl))
1052 /* On some machines, it is good to increase alignment sometimes. */
1053 #ifdef DATA_ALIGNMENT
1054 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1055 /* Don't increase alignment too much for TLS variables - TLS space
1056 is too precious. */
1057 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1058 align = data_align;
1059 #endif
1060 #ifdef CONSTANT_ALIGNMENT
1061 if (DECL_INITIAL (decl) != 0 && DECL_INITIAL (decl) != error_mark_node)
1063 unsigned int const_align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl),
1064 align);
1065 /* Don't increase alignment too much for TLS variables - TLS space
1066 is too precious. */
1067 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1068 align = const_align;
1070 #endif
1073 return align;
1076 /* Return the section into which the given VAR_DECL or CONST_DECL
1077 should be placed. PREFER_NOSWITCH_P is true if a noswitch
1078 section should be used wherever possible. */
1080 section *
1081 get_variable_section (tree decl, bool prefer_noswitch_p)
1083 addr_space_t as = ADDR_SPACE_GENERIC;
1084 int reloc;
1086 if (TREE_TYPE (decl) != error_mark_node)
1087 as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1089 if (DECL_COMMON (decl))
1091 /* If the decl has been given an explicit section name, or it resides
1092 in a non-generic address space, then it isn't common, and shouldn't
1093 be handled as such. */
1094 gcc_assert (DECL_SECTION_NAME (decl) == NULL
1095 && ADDR_SPACE_GENERIC_P (as));
1096 if (DECL_THREAD_LOCAL_P (decl))
1097 return tls_comm_section;
1098 else if (TREE_PUBLIC (decl) && bss_initializer_p (decl))
1099 return comm_section;
1102 if (DECL_INITIAL (decl) == error_mark_node)
1103 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1104 else if (DECL_INITIAL (decl))
1105 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1106 else
1107 reloc = 0;
1109 resolve_unique_section (decl, reloc, flag_data_sections);
1110 if (IN_NAMED_SECTION (decl))
1111 return get_named_section (decl, NULL, reloc);
1113 if (ADDR_SPACE_GENERIC_P (as)
1114 && !DECL_THREAD_LOCAL_P (decl)
1115 && !(prefer_noswitch_p && targetm.have_switchable_bss_sections)
1116 && bss_initializer_p (decl))
1118 if (!TREE_PUBLIC (decl)
1119 && !((flag_sanitize & SANITIZE_ADDRESS)
1120 && asan_protect_global (decl)))
1121 return lcomm_section;
1122 if (bss_noswitch_section)
1123 return bss_noswitch_section;
1126 return targetm.asm_out.select_section (decl, reloc,
1127 get_variable_align (decl));
1130 /* Return the block into which object_block DECL should be placed. */
1132 static struct object_block *
1133 get_block_for_decl (tree decl)
1135 section *sect;
1137 if (TREE_CODE (decl) == VAR_DECL)
1139 /* The object must be defined in this translation unit. */
1140 if (DECL_EXTERNAL (decl))
1141 return NULL;
1143 /* There's no point using object blocks for something that is
1144 isolated by definition. */
1145 if (DECL_ONE_ONLY (decl))
1146 return NULL;
1149 /* We can only calculate block offsets if the decl has a known
1150 constant size. */
1151 if (DECL_SIZE_UNIT (decl) == NULL)
1152 return NULL;
1153 if (!tree_fits_uhwi_p (DECL_SIZE_UNIT (decl)))
1154 return NULL;
1156 /* Find out which section should contain DECL. We cannot put it into
1157 an object block if it requires a standalone definition. */
1158 if (TREE_CODE (decl) == VAR_DECL)
1159 align_variable (decl, 0);
1160 sect = get_variable_section (decl, true);
1161 if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
1162 return NULL;
1164 return get_block_for_section (sect);
1167 /* Make sure block symbol SYMBOL is in block BLOCK. */
1169 static void
1170 change_symbol_block (rtx symbol, struct object_block *block)
1172 if (block != SYMBOL_REF_BLOCK (symbol))
1174 gcc_assert (SYMBOL_REF_BLOCK_OFFSET (symbol) < 0);
1175 SYMBOL_REF_BLOCK (symbol) = block;
1179 /* Return true if it is possible to put DECL in an object_block. */
1181 static bool
1182 use_blocks_for_decl_p (tree decl)
1184 /* Only data DECLs can be placed into object blocks. */
1185 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != CONST_DECL)
1186 return false;
1188 /* Detect decls created by dw2_force_const_mem. Such decls are
1189 special because DECL_INITIAL doesn't specify the decl's true value.
1190 dw2_output_indirect_constants will instead call assemble_variable
1191 with dont_output_data set to 1 and then print the contents itself. */
1192 if (DECL_INITIAL (decl) == decl)
1193 return false;
1195 /* If this decl is an alias, then we don't want to emit a
1196 definition. */
1197 if (lookup_attribute ("alias", DECL_ATTRIBUTES (decl)))
1198 return false;
1200 return targetm.use_blocks_for_decl_p (decl);
1203 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
1204 have static storage duration. In other words, it should not be an
1205 automatic variable, including PARM_DECLs.
1207 There is, however, one exception: this function handles variables
1208 explicitly placed in a particular register by the user.
1210 This is never called for PARM_DECL nodes. */
1212 void
1213 make_decl_rtl (tree decl)
1215 const char *name = 0;
1216 int reg_number;
1217 rtx x;
1219 /* Check that we are not being given an automatic variable. */
1220 gcc_assert (TREE_CODE (decl) != PARM_DECL
1221 && TREE_CODE (decl) != RESULT_DECL);
1223 /* A weak alias has TREE_PUBLIC set but not the other bits. */
1224 gcc_assert (TREE_CODE (decl) != VAR_DECL
1225 || TREE_STATIC (decl)
1226 || TREE_PUBLIC (decl)
1227 || DECL_EXTERNAL (decl)
1228 || DECL_REGISTER (decl));
1230 /* And that we were not given a type or a label. */
1231 gcc_assert (TREE_CODE (decl) != TYPE_DECL
1232 && TREE_CODE (decl) != LABEL_DECL);
1234 /* For a duplicate declaration, we can be called twice on the
1235 same DECL node. Don't discard the RTL already made. */
1236 if (DECL_RTL_SET_P (decl))
1238 /* If the old RTL had the wrong mode, fix the mode. */
1239 x = DECL_RTL (decl);
1240 if (GET_MODE (x) != DECL_MODE (decl))
1241 SET_DECL_RTL (decl, adjust_address_nv (x, DECL_MODE (decl), 0));
1243 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1244 return;
1246 /* ??? Another way to do this would be to maintain a hashed
1247 table of such critters. Instead of adding stuff to a DECL
1248 to give certain attributes to it, we could use an external
1249 hash map from DECL to set of attributes. */
1251 /* Let the target reassign the RTL if it wants.
1252 This is necessary, for example, when one machine specific
1253 decl attribute overrides another. */
1254 targetm.encode_section_info (decl, DECL_RTL (decl), false);
1256 /* If the symbol has a SYMBOL_REF_BLOCK field, update it based
1257 on the new decl information. */
1258 if (MEM_P (x)
1259 && GET_CODE (XEXP (x, 0)) == SYMBOL_REF
1260 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (x, 0)))
1261 change_symbol_block (XEXP (x, 0), get_block_for_decl (decl));
1263 return;
1266 /* If this variable belongs to the global constant pool, retrieve the
1267 pre-computed RTL or recompute it in LTO mode. */
1268 if (TREE_CODE (decl) == VAR_DECL && DECL_IN_CONSTANT_POOL (decl))
1270 SET_DECL_RTL (decl, output_constant_def (DECL_INITIAL (decl), 1));
1271 return;
1274 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
1276 if (name[0] != '*' && TREE_CODE (decl) != FUNCTION_DECL
1277 && DECL_REGISTER (decl))
1279 error ("register name not specified for %q+D", decl);
1281 else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1283 const char *asmspec = name+1;
1284 enum machine_mode mode = DECL_MODE (decl);
1285 reg_number = decode_reg_name (asmspec);
1286 /* First detect errors in declaring global registers. */
1287 if (reg_number == -1)
1288 error ("register name not specified for %q+D", decl);
1289 else if (reg_number < 0)
1290 error ("invalid register name for %q+D", decl);
1291 else if (mode == BLKmode)
1292 error ("data type of %q+D isn%'t suitable for a register",
1293 decl);
1294 else if (!in_hard_reg_set_p (accessible_reg_set, mode, reg_number))
1295 error ("the register specified for %q+D cannot be accessed"
1296 " by the current target", decl);
1297 else if (!in_hard_reg_set_p (operand_reg_set, mode, reg_number))
1298 error ("the register specified for %q+D is not general enough"
1299 " to be used as a register variable", decl);
1300 else if (!HARD_REGNO_MODE_OK (reg_number, mode))
1301 error ("register specified for %q+D isn%'t suitable for data type",
1302 decl);
1303 /* Now handle properly declared static register variables. */
1304 else
1306 int nregs;
1308 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
1310 DECL_INITIAL (decl) = 0;
1311 error ("global register variable has initial value");
1313 if (TREE_THIS_VOLATILE (decl))
1314 warning (OPT_Wvolatile_register_var,
1315 "optimization may eliminate reads and/or "
1316 "writes to register variables");
1318 /* If the user specified one of the eliminables registers here,
1319 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
1320 confused with that register and be eliminated. This usage is
1321 somewhat suspect... */
1323 SET_DECL_RTL (decl, gen_rtx_raw_REG (mode, reg_number));
1324 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
1325 REG_USERVAR_P (DECL_RTL (decl)) = 1;
1327 if (TREE_STATIC (decl))
1329 /* Make this register global, so not usable for anything
1330 else. */
1331 #ifdef ASM_DECLARE_REGISTER_GLOBAL
1332 name = IDENTIFIER_POINTER (DECL_NAME (decl));
1333 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
1334 #endif
1335 nregs = hard_regno_nregs[reg_number][mode];
1336 while (nregs > 0)
1337 globalize_reg (decl, reg_number + --nregs);
1340 /* As a register variable, it has no section. */
1341 return;
1344 /* Now handle ordinary static variables and functions (in memory).
1345 Also handle vars declared register invalidly. */
1346 else if (name[0] == '*')
1348 #ifdef REGISTER_PREFIX
1349 if (strlen (REGISTER_PREFIX) != 0)
1351 reg_number = decode_reg_name (name);
1352 if (reg_number >= 0 || reg_number == -3)
1353 error ("register name given for non-register variable %q+D", decl);
1355 #endif
1358 /* Specifying a section attribute on a variable forces it into a
1359 non-.bss section, and thus it cannot be common. */
1360 /* FIXME: In general this code should not be necessary because
1361 visibility pass is doing the same work. But notice_global_symbol
1362 is called early and it needs to make DECL_RTL to get the name.
1363 we take care of recomputing the DECL_RTL after visibility is changed. */
1364 if (TREE_CODE (decl) == VAR_DECL
1365 && DECL_SECTION_NAME (decl) != NULL_TREE
1366 && DECL_INITIAL (decl) == NULL_TREE
1367 && DECL_COMMON (decl))
1368 DECL_COMMON (decl) = 0;
1370 /* Variables can't be both common and weak. */
1371 if (TREE_CODE (decl) == VAR_DECL && DECL_WEAK (decl))
1372 DECL_COMMON (decl) = 0;
1374 if (use_object_blocks_p () && use_blocks_for_decl_p (decl))
1375 x = create_block_symbol (name, get_block_for_decl (decl), -1);
1376 else
1378 enum machine_mode address_mode = Pmode;
1379 if (TREE_TYPE (decl) != error_mark_node)
1381 addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1382 address_mode = targetm.addr_space.address_mode (as);
1384 x = gen_rtx_SYMBOL_REF (address_mode, name);
1386 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
1387 SET_SYMBOL_REF_DECL (x, decl);
1389 x = gen_rtx_MEM (DECL_MODE (decl), x);
1390 if (TREE_CODE (decl) != FUNCTION_DECL)
1391 set_mem_attributes (x, decl, 1);
1392 SET_DECL_RTL (decl, x);
1394 /* Optionally set flags or add text to the name to record information
1395 such as that it is a function name.
1396 If the name is changed, the macro ASM_OUTPUT_LABELREF
1397 will have to know how to strip this information. */
1398 targetm.encode_section_info (decl, DECL_RTL (decl), true);
1401 /* Like make_decl_rtl, but inhibit creation of new alias sets when
1402 calling make_decl_rtl. Also, reset DECL_RTL before returning the
1403 rtl. */
1406 make_decl_rtl_for_debug (tree decl)
1408 unsigned int save_aliasing_flag;
1409 rtx rtl;
1411 if (DECL_RTL_SET_P (decl))
1412 return DECL_RTL (decl);
1414 /* Kludge alert! Somewhere down the call chain, make_decl_rtl will
1415 call new_alias_set. If running with -fcompare-debug, sometimes
1416 we do not want to create alias sets that will throw the alias
1417 numbers off in the comparison dumps. So... clearing
1418 flag_strict_aliasing will keep new_alias_set() from creating a
1419 new set. */
1420 save_aliasing_flag = flag_strict_aliasing;
1421 flag_strict_aliasing = 0;
1423 rtl = DECL_RTL (decl);
1424 /* Reset DECL_RTL back, as various parts of the compiler expects
1425 DECL_RTL set meaning it is actually going to be output. */
1426 SET_DECL_RTL (decl, NULL);
1428 flag_strict_aliasing = save_aliasing_flag;
1429 return rtl;
1432 /* Output a string of literal assembler code
1433 for an `asm' keyword used between functions. */
1435 void
1436 assemble_asm (tree string)
1438 const char *p;
1439 app_enable ();
1441 if (TREE_CODE (string) == ADDR_EXPR)
1442 string = TREE_OPERAND (string, 0);
1444 p = TREE_STRING_POINTER (string);
1445 fprintf (asm_out_file, "%s%s\n", p[0] == '\t' ? "" : "\t", p);
1448 /* Write the address of the entity given by SYMBOL to SEC. */
1449 void
1450 assemble_addr_to_section (rtx symbol, section *sec)
1452 switch_to_section (sec);
1453 assemble_align (POINTER_SIZE);
1454 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1457 /* Return the numbered .ctors.N (if CONSTRUCTOR_P) or .dtors.N (if
1458 not) section for PRIORITY. */
1459 section *
1460 get_cdtor_priority_section (int priority, bool constructor_p)
1462 char buf[16];
1464 /* ??? This only works reliably with the GNU linker. */
1465 sprintf (buf, "%s.%.5u",
1466 constructor_p ? ".ctors" : ".dtors",
1467 /* Invert the numbering so the linker puts us in the proper
1468 order; constructors are run from right to left, and the
1469 linker sorts in increasing order. */
1470 MAX_INIT_PRIORITY - priority);
1471 return get_section (buf, SECTION_WRITE, NULL);
1474 void
1475 default_named_section_asm_out_destructor (rtx symbol, int priority)
1477 section *sec;
1479 if (priority != DEFAULT_INIT_PRIORITY)
1480 sec = get_cdtor_priority_section (priority,
1481 /*constructor_p=*/false);
1482 else
1483 sec = get_section (".dtors", SECTION_WRITE, NULL);
1485 assemble_addr_to_section (symbol, sec);
1488 #ifdef DTORS_SECTION_ASM_OP
1489 void
1490 default_dtor_section_asm_out_destructor (rtx symbol,
1491 int priority ATTRIBUTE_UNUSED)
1493 assemble_addr_to_section (symbol, dtors_section);
1495 #endif
1497 void
1498 default_named_section_asm_out_constructor (rtx symbol, int priority)
1500 section *sec;
1502 if (priority != DEFAULT_INIT_PRIORITY)
1503 sec = get_cdtor_priority_section (priority,
1504 /*constructor_p=*/true);
1505 else
1506 sec = get_section (".ctors", SECTION_WRITE, NULL);
1508 assemble_addr_to_section (symbol, sec);
1511 #ifdef CTORS_SECTION_ASM_OP
1512 void
1513 default_ctor_section_asm_out_constructor (rtx symbol,
1514 int priority ATTRIBUTE_UNUSED)
1516 assemble_addr_to_section (symbol, ctors_section);
1518 #endif
1520 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1521 a nonzero value if the constant pool should be output before the
1522 start of the function, or a zero value if the pool should output
1523 after the end of the function. The default is to put it before the
1524 start. */
1526 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1527 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1528 #endif
1530 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1531 to be output to assembler.
1532 Set first_global_object_name and weak_global_object_name as appropriate. */
1534 void
1535 notice_global_symbol (tree decl)
1537 const char **type = &first_global_object_name;
1539 if (first_global_object_name
1540 || !TREE_PUBLIC (decl)
1541 || DECL_EXTERNAL (decl)
1542 || !DECL_NAME (decl)
1543 || (TREE_CODE (decl) != FUNCTION_DECL
1544 && (TREE_CODE (decl) != VAR_DECL
1545 || (DECL_COMMON (decl)
1546 && (DECL_INITIAL (decl) == 0
1547 || DECL_INITIAL (decl) == error_mark_node))))
1548 || !MEM_P (DECL_RTL (decl)))
1549 return;
1551 /* We win when global object is found, but it is useful to know about weak
1552 symbol as well so we can produce nicer unique names. */
1553 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl) || flag_shlib)
1554 type = &weak_global_object_name;
1556 if (!*type)
1558 const char *p;
1559 const char *name;
1560 rtx decl_rtl = DECL_RTL (decl);
1562 p = targetm.strip_name_encoding (XSTR (XEXP (decl_rtl, 0), 0));
1563 name = ggc_strdup (p);
1565 *type = name;
1569 /* If not using flag_reorder_blocks_and_partition, decide early whether the
1570 current function goes into the cold section, so that targets can use
1571 current_function_section during RTL expansion. DECL describes the
1572 function. */
1574 void
1575 decide_function_section (tree decl)
1577 first_function_block_is_cold = false;
1579 if (flag_reorder_blocks_and_partition)
1580 /* We will decide in assemble_start_function. */
1581 return;
1583 if (DECL_SECTION_NAME (decl))
1585 struct cgraph_node *node = cgraph_get_node (current_function_decl);
1586 /* Calls to function_section rely on first_function_block_is_cold
1587 being accurate. */
1588 first_function_block_is_cold = (node
1589 && node->frequency
1590 == NODE_FREQUENCY_UNLIKELY_EXECUTED);
1593 in_cold_section_p = first_function_block_is_cold;
1596 /* Output assembler code for the constant pool of a function and associated
1597 with defining the name of the function. DECL describes the function.
1598 NAME is the function's name. For the constant pool, we use the current
1599 constant pool data. */
1601 void
1602 assemble_start_function (tree decl, const char *fnname)
1604 int align;
1605 char tmp_label[100];
1606 bool hot_label_written = false;
1608 if (flag_reorder_blocks_and_partition)
1610 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTB", const_labelno);
1611 crtl->subsections.hot_section_label = ggc_strdup (tmp_label);
1612 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDB", const_labelno);
1613 crtl->subsections.cold_section_label = ggc_strdup (tmp_label);
1614 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTE", const_labelno);
1615 crtl->subsections.hot_section_end_label = ggc_strdup (tmp_label);
1616 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDE", const_labelno);
1617 crtl->subsections.cold_section_end_label = ggc_strdup (tmp_label);
1618 const_labelno++;
1620 else
1622 crtl->subsections.hot_section_label = NULL;
1623 crtl->subsections.cold_section_label = NULL;
1624 crtl->subsections.hot_section_end_label = NULL;
1625 crtl->subsections.cold_section_end_label = NULL;
1628 /* The following code does not need preprocessing in the assembler. */
1630 app_disable ();
1632 if (CONSTANT_POOL_BEFORE_FUNCTION)
1633 output_constant_pool (fnname, decl);
1635 /* Make sure the not and cold text (code) sections are properly
1636 aligned. This is necessary here in the case where the function
1637 has both hot and cold sections, because we don't want to re-set
1638 the alignment when the section switch happens mid-function. */
1640 if (flag_reorder_blocks_and_partition)
1642 first_function_block_is_cold = false;
1644 switch_to_section (unlikely_text_section ());
1645 assemble_align (DECL_ALIGN (decl));
1646 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_label);
1648 /* When the function starts with a cold section, we need to explicitly
1649 align the hot section and write out the hot section label.
1650 But if the current function is a thunk, we do not have a CFG. */
1651 if (!cfun->is_thunk
1652 && BB_PARTITION (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) == BB_COLD_PARTITION)
1654 switch_to_section (text_section);
1655 assemble_align (DECL_ALIGN (decl));
1656 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1657 hot_label_written = true;
1658 first_function_block_is_cold = true;
1660 in_cold_section_p = first_function_block_is_cold;
1664 /* Switch to the correct text section for the start of the function. */
1666 switch_to_section (function_section (decl));
1667 if (flag_reorder_blocks_and_partition
1668 && !hot_label_written)
1669 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1671 /* Tell assembler to move to target machine's alignment for functions. */
1672 align = floor_log2 (DECL_ALIGN (decl) / BITS_PER_UNIT);
1673 if (align > 0)
1675 ASM_OUTPUT_ALIGN (asm_out_file, align);
1678 /* Handle a user-specified function alignment.
1679 Note that we still need to align to DECL_ALIGN, as above,
1680 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1681 if (! DECL_USER_ALIGN (decl)
1682 && align_functions_log > align
1683 && optimize_function_for_speed_p (cfun))
1685 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1686 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1687 align_functions_log, align_functions - 1);
1688 #else
1689 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1690 #endif
1693 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1694 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1695 #endif
1697 if (!DECL_IGNORED_P (decl))
1698 (*debug_hooks->begin_function) (decl);
1700 /* Make function name accessible from other files, if appropriate. */
1702 if (TREE_PUBLIC (decl))
1704 notice_global_symbol (decl);
1706 globalize_decl (decl);
1708 maybe_assemble_visibility (decl);
1711 if (DECL_PRESERVE_P (decl))
1712 targetm.asm_out.mark_decl_preserved (fnname);
1714 /* Do any machine/system dependent processing of the function name. */
1715 #ifdef ASM_DECLARE_FUNCTION_NAME
1716 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1717 #else
1718 /* Standard thing is just output label for the function. */
1719 ASM_OUTPUT_FUNCTION_LABEL (asm_out_file, fnname, current_function_decl);
1720 #endif /* ASM_DECLARE_FUNCTION_NAME */
1722 if (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (decl)))
1723 saw_no_split_stack = true;
1726 /* Output assembler code associated with defining the size of the
1727 function. DECL describes the function. NAME is the function's name. */
1729 void
1730 assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED)
1732 #ifdef ASM_DECLARE_FUNCTION_SIZE
1733 /* We could have switched section in the middle of the function. */
1734 if (flag_reorder_blocks_and_partition)
1735 switch_to_section (function_section (decl));
1736 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1737 #endif
1738 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1740 output_constant_pool (fnname, decl);
1741 switch_to_section (function_section (decl)); /* need to switch back */
1743 /* Output labels for end of hot/cold text sections (to be used by
1744 debug info.) */
1745 if (flag_reorder_blocks_and_partition)
1747 section *save_text_section;
1749 save_text_section = in_section;
1750 switch_to_section (unlikely_text_section ());
1751 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label);
1752 if (first_function_block_is_cold)
1753 switch_to_section (text_section);
1754 else
1755 switch_to_section (function_section (decl));
1756 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label);
1757 switch_to_section (save_text_section);
1761 /* Assemble code to leave SIZE bytes of zeros. */
1763 void
1764 assemble_zeros (unsigned HOST_WIDE_INT size)
1766 /* Do no output if -fsyntax-only. */
1767 if (flag_syntax_only)
1768 return;
1770 #ifdef ASM_NO_SKIP_IN_TEXT
1771 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1772 so we must output 0s explicitly in the text section. */
1773 if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0)
1775 unsigned HOST_WIDE_INT i;
1776 for (i = 0; i < size; i++)
1777 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1779 else
1780 #endif
1781 if (size > 0)
1782 ASM_OUTPUT_SKIP (asm_out_file, size);
1785 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1787 void
1788 assemble_align (int align)
1790 if (align > BITS_PER_UNIT)
1792 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1796 /* Assemble a string constant with the specified C string as contents. */
1798 void
1799 assemble_string (const char *p, int size)
1801 int pos = 0;
1802 int maximum = 2000;
1804 /* If the string is very long, split it up. */
1806 while (pos < size)
1808 int thissize = size - pos;
1809 if (thissize > maximum)
1810 thissize = maximum;
1812 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1814 pos += thissize;
1815 p += thissize;
1820 /* A noswitch_section_callback for lcomm_section. */
1822 static bool
1823 emit_local (tree decl ATTRIBUTE_UNUSED,
1824 const char *name ATTRIBUTE_UNUSED,
1825 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1826 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1828 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1829 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name,
1830 size, DECL_ALIGN (decl));
1831 return true;
1832 #elif defined ASM_OUTPUT_ALIGNED_LOCAL
1833 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, DECL_ALIGN (decl));
1834 return true;
1835 #else
1836 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1837 return false;
1838 #endif
1841 /* A noswitch_section_callback for bss_noswitch_section. */
1843 #if defined ASM_OUTPUT_ALIGNED_BSS
1844 static bool
1845 emit_bss (tree decl ATTRIBUTE_UNUSED,
1846 const char *name ATTRIBUTE_UNUSED,
1847 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1848 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1850 #if defined ASM_OUTPUT_ALIGNED_BSS
1851 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size,
1852 get_variable_align (decl));
1853 return true;
1854 #endif
1856 #endif
1858 /* A noswitch_section_callback for comm_section. */
1860 static bool
1861 emit_common (tree decl ATTRIBUTE_UNUSED,
1862 const char *name ATTRIBUTE_UNUSED,
1863 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1864 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1866 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1867 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name,
1868 size, get_variable_align (decl));
1869 return true;
1870 #elif defined ASM_OUTPUT_ALIGNED_COMMON
1871 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size,
1872 get_variable_align (decl));
1873 return true;
1874 #else
1875 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
1876 return false;
1877 #endif
1880 /* A noswitch_section_callback for tls_comm_section. */
1882 static bool
1883 emit_tls_common (tree decl ATTRIBUTE_UNUSED,
1884 const char *name ATTRIBUTE_UNUSED,
1885 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1886 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1888 #ifdef ASM_OUTPUT_TLS_COMMON
1889 ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size);
1890 return true;
1891 #else
1892 sorry ("thread-local COMMON data not implemented");
1893 return true;
1894 #endif
1897 /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT.
1898 NAME is the name of DECL's SYMBOL_REF. */
1900 static void
1901 assemble_noswitch_variable (tree decl, const char *name, section *sect,
1902 unsigned int align)
1904 unsigned HOST_WIDE_INT size, rounded;
1906 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
1907 rounded = size;
1909 if ((flag_sanitize & SANITIZE_ADDRESS) && asan_protect_global (decl))
1910 size += asan_red_zone_size (size);
1912 /* Don't allocate zero bytes of common,
1913 since that means "undefined external" in the linker. */
1914 if (size == 0)
1915 rounded = 1;
1917 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1918 so that each uninitialized object starts on such a boundary. */
1919 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
1920 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1921 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1923 if (!sect->noswitch.callback (decl, name, size, rounded)
1924 && (unsigned HOST_WIDE_INT) (align / BITS_PER_UNIT) > rounded)
1925 error ("requested alignment for %q+D is greater than "
1926 "implemented alignment of %wu", decl, rounded);
1929 /* A subroutine of assemble_variable. Output the label and contents of
1930 DECL, whose address is a SYMBOL_REF with name NAME. DONT_OUTPUT_DATA
1931 is as for assemble_variable. */
1933 static void
1934 assemble_variable_contents (tree decl, const char *name,
1935 bool dont_output_data)
1937 /* Do any machine/system dependent processing of the object. */
1938 #ifdef ASM_DECLARE_OBJECT_NAME
1939 last_assemble_variable_decl = decl;
1940 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
1941 #else
1942 /* Standard thing is just output label for the object. */
1943 ASM_OUTPUT_LABEL (asm_out_file, name);
1944 #endif /* ASM_DECLARE_OBJECT_NAME */
1946 if (!dont_output_data)
1948 if (DECL_INITIAL (decl)
1949 && DECL_INITIAL (decl) != error_mark_node
1950 && !initializer_zerop (DECL_INITIAL (decl)))
1951 /* Output the actual data. */
1952 output_constant (DECL_INITIAL (decl),
1953 tree_to_uhwi (DECL_SIZE_UNIT (decl)),
1954 get_variable_align (decl));
1955 else
1956 /* Leave space for it. */
1957 assemble_zeros (tree_to_uhwi (DECL_SIZE_UNIT (decl)));
1961 /* Assemble everything that is needed for a variable or function declaration.
1962 Not used for automatic variables, and not used for function definitions.
1963 Should not be called for variables of incomplete structure type.
1965 TOP_LEVEL is nonzero if this variable has file scope.
1966 AT_END is nonzero if this is the special handling, at end of compilation,
1967 to define things that have had only tentative definitions.
1968 DONT_OUTPUT_DATA if nonzero means don't actually output the
1969 initial value (that will be done by the caller). */
1971 void
1972 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
1973 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
1975 const char *name;
1976 rtx decl_rtl, symbol;
1977 section *sect;
1978 unsigned int align;
1979 bool asan_protected = false;
1981 /* This function is supposed to handle VARIABLES. Ensure we have one. */
1982 gcc_assert (TREE_CODE (decl) == VAR_DECL);
1984 /* Emulated TLS had better not get this far. */
1985 gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl));
1987 last_assemble_variable_decl = 0;
1989 /* Normally no need to say anything here for external references,
1990 since assemble_external is called by the language-specific code
1991 when a declaration is first seen. */
1993 if (DECL_EXTERNAL (decl))
1994 return;
1996 /* Do nothing for global register variables. */
1997 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
1999 TREE_ASM_WRITTEN (decl) = 1;
2000 return;
2003 /* If type was incomplete when the variable was declared,
2004 see if it is complete now. */
2006 if (DECL_SIZE (decl) == 0)
2007 layout_decl (decl, 0);
2009 /* Still incomplete => don't allocate it; treat the tentative defn
2010 (which is what it must have been) as an `extern' reference. */
2012 if (!dont_output_data && DECL_SIZE (decl) == 0)
2014 error ("storage size of %q+D isn%'t known", decl);
2015 TREE_ASM_WRITTEN (decl) = 1;
2016 return;
2019 /* The first declaration of a variable that comes through this function
2020 decides whether it is global (in C, has external linkage)
2021 or local (in C, has internal linkage). So do nothing more
2022 if this function has already run. */
2024 if (TREE_ASM_WRITTEN (decl))
2025 return;
2027 /* Make sure targetm.encode_section_info is invoked before we set
2028 ASM_WRITTEN. */
2029 decl_rtl = DECL_RTL (decl);
2031 TREE_ASM_WRITTEN (decl) = 1;
2033 /* Do no output if -fsyntax-only. */
2034 if (flag_syntax_only)
2035 return;
2037 if (! dont_output_data
2038 && ! valid_constant_size_p (DECL_SIZE_UNIT (decl)))
2040 error ("size of variable %q+D is too large", decl);
2041 return;
2044 gcc_assert (MEM_P (decl_rtl));
2045 gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF);
2046 symbol = XEXP (decl_rtl, 0);
2048 /* If this symbol belongs to the tree constant pool, output the constant
2049 if it hasn't already been written. */
2050 if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
2052 tree decl = SYMBOL_REF_DECL (symbol);
2053 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
2054 output_constant_def_contents (symbol);
2055 return;
2058 app_disable ();
2060 name = XSTR (symbol, 0);
2061 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
2062 notice_global_symbol (decl);
2064 /* Compute the alignment of this data. */
2066 align_variable (decl, dont_output_data);
2068 if ((flag_sanitize & SANITIZE_ADDRESS)
2069 && asan_protect_global (decl))
2071 asan_protected = true;
2072 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
2073 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
2076 set_mem_align (decl_rtl, DECL_ALIGN (decl));
2078 align = get_variable_align (decl);
2080 if (TREE_PUBLIC (decl))
2081 maybe_assemble_visibility (decl);
2083 if (DECL_PRESERVE_P (decl))
2084 targetm.asm_out.mark_decl_preserved (name);
2086 /* First make the assembler name(s) global if appropriate. */
2087 sect = get_variable_section (decl, false);
2088 if (TREE_PUBLIC (decl)
2089 && (sect->common.flags & SECTION_COMMON) == 0)
2090 globalize_decl (decl);
2092 /* Output any data that we will need to use the address of. */
2093 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
2094 output_addressed_constants (DECL_INITIAL (decl));
2096 /* dbxout.c needs to know this. */
2097 if (sect && (sect->common.flags & SECTION_CODE) != 0)
2098 DECL_IN_TEXT_SECTION (decl) = 1;
2100 /* If the decl is part of an object_block, make sure that the decl
2101 has been positioned within its block, but do not write out its
2102 definition yet. output_object_blocks will do that later. */
2103 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
2105 gcc_assert (!dont_output_data);
2106 place_block_symbol (symbol);
2108 else if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
2109 assemble_noswitch_variable (decl, name, sect, align);
2110 else
2112 /* The following bit of code ensures that vtable_map
2113 variables are not only in the comdat section, but that
2114 each variable has its own unique comdat name. If this
2115 code is removed, the variables end up in the same section
2116 with a single comdat name.
2118 FIXME: resolve_unique_section needs to deal better with
2119 decls with both DECL_SECTION_NAME and DECL_ONE_ONLY. Once
2120 that is fixed, this if-else statement can be replaced with
2121 a single call to "switch_to_section (sect)". */
2122 if (sect->named.name
2123 && (strcmp (sect->named.name, ".vtable_map_vars") == 0))
2125 #if defined (OBJECT_FORMAT_ELF)
2126 targetm.asm_out.named_section (sect->named.name,
2127 sect->named.common.flags
2128 | SECTION_LINKONCE,
2129 DECL_NAME (decl));
2130 in_section = sect;
2131 #else
2132 switch_to_section (sect);
2133 #endif
2135 else
2136 switch_to_section (sect);
2137 if (align > BITS_PER_UNIT)
2138 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2139 assemble_variable_contents (decl, name, dont_output_data);
2140 if (asan_protected)
2142 unsigned HOST_WIDE_INT int size
2143 = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2144 assemble_zeros (asan_red_zone_size (size));
2150 /* Given a function declaration (FN_DECL), this function assembles the
2151 function into the .preinit_array section. */
2153 void
2154 assemble_vtv_preinit_initializer (tree fn_decl)
2156 section *sect;
2157 unsigned flags = SECTION_WRITE;
2158 rtx symbol = XEXP (DECL_RTL (fn_decl), 0);
2160 flags |= SECTION_NOTYPE;
2161 sect = get_section (".preinit_array", flags, fn_decl);
2162 switch_to_section (sect);
2163 assemble_addr_to_section (symbol, sect);
2166 /* Return 1 if type TYPE contains any pointers. */
2168 static int
2169 contains_pointers_p (tree type)
2171 switch (TREE_CODE (type))
2173 case POINTER_TYPE:
2174 case REFERENCE_TYPE:
2175 /* I'm not sure whether OFFSET_TYPE needs this treatment,
2176 so I'll play safe and return 1. */
2177 case OFFSET_TYPE:
2178 return 1;
2180 case RECORD_TYPE:
2181 case UNION_TYPE:
2182 case QUAL_UNION_TYPE:
2184 tree fields;
2185 /* For a type that has fields, see if the fields have pointers. */
2186 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2187 if (TREE_CODE (fields) == FIELD_DECL
2188 && contains_pointers_p (TREE_TYPE (fields)))
2189 return 1;
2190 return 0;
2193 case ARRAY_TYPE:
2194 /* An array type contains pointers if its element type does. */
2195 return contains_pointers_p (TREE_TYPE (type));
2197 default:
2198 return 0;
2202 /* We delay assemble_external processing until
2203 the compilation unit is finalized. This is the best we can do for
2204 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2205 it all the way to final. See PR 17982 for further discussion. */
2206 static GTY(()) tree pending_assemble_externals;
2208 #ifdef ASM_OUTPUT_EXTERNAL
2209 /* Some targets delay some output to final using TARGET_ASM_FILE_END.
2210 As a result, assemble_external can be called after the list of externals
2211 is processed and the pointer set destroyed. */
2212 static bool pending_assemble_externals_processed;
2214 /* Avoid O(external_decls**2) lookups in the pending_assemble_externals
2215 TREE_LIST in assemble_external. */
2216 static struct pointer_set_t *pending_assemble_externals_set;
2218 /* True if DECL is a function decl for which no out-of-line copy exists.
2219 It is assumed that DECL's assembler name has been set. */
2221 static bool
2222 incorporeal_function_p (tree decl)
2224 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
2226 const char *name;
2228 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2229 && (DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA
2230 || DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA_WITH_ALIGN))
2231 return true;
2233 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2234 /* Atomic or sync builtins which have survived this far will be
2235 resolved externally and therefore are not incorporeal. */
2236 if (strncmp (name, "__builtin_", 10) == 0)
2237 return true;
2239 return false;
2242 /* Actually do the tests to determine if this is necessary, and invoke
2243 ASM_OUTPUT_EXTERNAL. */
2244 static void
2245 assemble_external_real (tree decl)
2247 rtx rtl = DECL_RTL (decl);
2249 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2250 && !SYMBOL_REF_USED (XEXP (rtl, 0))
2251 && !incorporeal_function_p (decl))
2253 /* Some systems do require some output. */
2254 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2255 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2258 #endif
2260 void
2261 process_pending_assemble_externals (void)
2263 #ifdef ASM_OUTPUT_EXTERNAL
2264 tree list;
2265 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2266 assemble_external_real (TREE_VALUE (list));
2268 pending_assemble_externals = 0;
2269 pending_assemble_externals_processed = true;
2270 pointer_set_destroy (pending_assemble_externals_set);
2271 #endif
2274 /* This TREE_LIST contains any weak symbol declarations waiting
2275 to be emitted. */
2276 static GTY(()) tree weak_decls;
2278 /* Output something to declare an external symbol to the assembler,
2279 and qualifiers such as weakness. (Most assemblers don't need
2280 extern declaration, so we normally output nothing.) Do nothing if
2281 DECL is not external. */
2283 void
2284 assemble_external (tree decl ATTRIBUTE_UNUSED)
2286 /* Make sure that the ASM_OUT_FILE is open.
2287 If it's not, we should not be calling this function. */
2288 gcc_assert (asm_out_file);
2290 /* In a perfect world, the following condition would be true.
2291 Sadly, the Java and Go front ends emit assembly *from the front end*,
2292 bypassing the call graph. See PR52739. Fix before GCC 4.8. */
2293 #if 0
2294 /* This function should only be called if we are expanding, or have
2295 expanded, to RTL.
2296 Ideally, only final.c would be calling this function, but it is
2297 not clear whether that would break things somehow. See PR 17982
2298 for further discussion. */
2299 gcc_assert (cgraph_state == CGRAPH_STATE_EXPANSION
2300 || cgraph_state == CGRAPH_STATE_FINISHED);
2301 #endif
2303 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2304 return;
2306 /* We want to output annotation for weak and external symbols at
2307 very last to check if they are references or not. */
2309 if (TARGET_SUPPORTS_WEAK
2310 && DECL_WEAK (decl)
2311 /* TREE_STATIC is a weird and abused creature which is not
2312 generally the right test for whether an entity has been
2313 locally emitted, inlined or otherwise not-really-extern, but
2314 for declarations that can be weak, it happens to be
2315 match. */
2316 && !TREE_STATIC (decl)
2317 && lookup_attribute ("weak", DECL_ATTRIBUTES (decl))
2318 && value_member (decl, weak_decls) == NULL_TREE)
2319 weak_decls = tree_cons (NULL, decl, weak_decls);
2321 #ifdef ASM_OUTPUT_EXTERNAL
2322 if (pending_assemble_externals_processed)
2324 assemble_external_real (decl);
2325 return;
2328 if (! pointer_set_insert (pending_assemble_externals_set, decl))
2329 pending_assemble_externals = tree_cons (NULL, decl,
2330 pending_assemble_externals);
2331 #endif
2334 /* Similar, for calling a library function FUN. */
2336 void
2337 assemble_external_libcall (rtx fun)
2339 /* Declare library function name external when first used, if nec. */
2340 if (! SYMBOL_REF_USED (fun))
2342 SYMBOL_REF_USED (fun) = 1;
2343 targetm.asm_out.external_libcall (fun);
2347 /* Assemble a label named NAME. */
2349 void
2350 assemble_label (FILE *file, const char *name)
2352 ASM_OUTPUT_LABEL (file, name);
2355 /* Set the symbol_referenced flag for ID. */
2356 void
2357 mark_referenced (tree id)
2359 TREE_SYMBOL_REFERENCED (id) = 1;
2362 /* Set the symbol_referenced flag for DECL and notify callgraph. */
2363 void
2364 mark_decl_referenced (tree decl)
2366 if (TREE_CODE (decl) == FUNCTION_DECL)
2368 /* Extern inline functions don't become needed when referenced.
2369 If we know a method will be emitted in other TU and no new
2370 functions can be marked reachable, just use the external
2371 definition. */
2372 struct cgraph_node *node = cgraph_get_create_node (decl);
2373 if (!DECL_EXTERNAL (decl)
2374 && !node->definition)
2375 cgraph_mark_force_output_node (node);
2377 else if (TREE_CODE (decl) == VAR_DECL)
2379 varpool_node *node = varpool_node_for_decl (decl);
2380 /* C++ frontend use mark_decl_references to force COMDAT variables
2381 to be output that might appear dead otherwise. */
2382 node->force_output = true;
2384 /* else do nothing - we can get various sorts of CST nodes here,
2385 which do not need to be marked. */
2389 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS
2390 until we find an identifier that is not itself a transparent alias.
2391 Modify the alias passed to it by reference (and all aliases on the
2392 way to the ultimate target), such that they do not have to be
2393 followed again, and return the ultimate target of the alias
2394 chain. */
2396 static inline tree
2397 ultimate_transparent_alias_target (tree *alias)
2399 tree target = *alias;
2401 if (IDENTIFIER_TRANSPARENT_ALIAS (target))
2403 gcc_assert (TREE_CHAIN (target));
2404 target = ultimate_transparent_alias_target (&TREE_CHAIN (target));
2405 gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target)
2406 && ! TREE_CHAIN (target));
2407 *alias = target;
2410 return target;
2413 /* Output to FILE (an assembly file) a reference to NAME. If NAME
2414 starts with a *, the rest of NAME is output verbatim. Otherwise
2415 NAME is transformed in a target-specific way (usually by the
2416 addition of an underscore). */
2418 void
2419 assemble_name_raw (FILE *file, const char *name)
2421 if (name[0] == '*')
2422 fputs (&name[1], file);
2423 else
2424 ASM_OUTPUT_LABELREF (file, name);
2427 /* Like assemble_name_raw, but should be used when NAME might refer to
2428 an entity that is also represented as a tree (like a function or
2429 variable). If NAME does refer to such an entity, that entity will
2430 be marked as referenced. */
2432 void
2433 assemble_name (FILE *file, const char *name)
2435 const char *real_name;
2436 tree id;
2438 real_name = targetm.strip_name_encoding (name);
2440 id = maybe_get_identifier (real_name);
2441 if (id)
2443 tree id_orig = id;
2445 mark_referenced (id);
2446 ultimate_transparent_alias_target (&id);
2447 if (id != id_orig)
2448 name = IDENTIFIER_POINTER (id);
2449 gcc_assert (! TREE_CHAIN (id));
2452 assemble_name_raw (file, name);
2455 /* Allocate SIZE bytes writable static space with a gensym name
2456 and return an RTX to refer to its address. */
2459 assemble_static_space (unsigned HOST_WIDE_INT size)
2461 char name[12];
2462 const char *namestring;
2463 rtx x;
2465 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2466 ++const_labelno;
2467 namestring = ggc_strdup (name);
2469 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2470 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2472 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2473 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2474 BIGGEST_ALIGNMENT);
2475 #else
2476 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2477 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2478 #else
2480 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2481 so that each uninitialized object starts on such a boundary. */
2482 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2483 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2484 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2485 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2486 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2487 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2489 #endif
2490 #endif
2491 return x;
2494 /* Assemble the static constant template for function entry trampolines.
2495 This is done at most once per compilation.
2496 Returns an RTX for the address of the template. */
2498 static GTY(()) rtx initial_trampoline;
2501 assemble_trampoline_template (void)
2503 char label[256];
2504 const char *name;
2505 int align;
2506 rtx symbol;
2508 gcc_assert (targetm.asm_out.trampoline_template != NULL);
2510 if (initial_trampoline)
2511 return initial_trampoline;
2513 /* By default, put trampoline templates in read-only data section. */
2515 #ifdef TRAMPOLINE_SECTION
2516 switch_to_section (TRAMPOLINE_SECTION);
2517 #else
2518 switch_to_section (readonly_data_section);
2519 #endif
2521 /* Write the assembler code to define one. */
2522 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2523 if (align > 0)
2524 ASM_OUTPUT_ALIGN (asm_out_file, align);
2526 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2527 targetm.asm_out.trampoline_template (asm_out_file);
2529 /* Record the rtl to refer to it. */
2530 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2531 name = ggc_strdup (label);
2532 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2533 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2535 initial_trampoline = gen_const_mem (BLKmode, symbol);
2536 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2537 set_mem_size (initial_trampoline, TRAMPOLINE_SIZE);
2539 return initial_trampoline;
2542 /* A and B are either alignments or offsets. Return the minimum alignment
2543 that may be assumed after adding the two together. */
2545 static inline unsigned
2546 min_align (unsigned int a, unsigned int b)
2548 return (a | b) & -(a | b);
2551 /* Return the assembler directive for creating a given kind of integer
2552 object. SIZE is the number of bytes in the object and ALIGNED_P
2553 indicates whether it is known to be aligned. Return NULL if the
2554 assembly dialect has no such directive.
2556 The returned string should be printed at the start of a new line and
2557 be followed immediately by the object's initial value. */
2559 const char *
2560 integer_asm_op (int size, int aligned_p)
2562 struct asm_int_op *ops;
2564 if (aligned_p)
2565 ops = &targetm.asm_out.aligned_op;
2566 else
2567 ops = &targetm.asm_out.unaligned_op;
2569 switch (size)
2571 case 1:
2572 return targetm.asm_out.byte_op;
2573 case 2:
2574 return ops->hi;
2575 case 4:
2576 return ops->si;
2577 case 8:
2578 return ops->di;
2579 case 16:
2580 return ops->ti;
2581 default:
2582 return NULL;
2586 /* Use directive OP to assemble an integer object X. Print OP at the
2587 start of the line, followed immediately by the value of X. */
2589 void
2590 assemble_integer_with_op (const char *op, rtx x)
2592 fputs (op, asm_out_file);
2593 output_addr_const (asm_out_file, x);
2594 fputc ('\n', asm_out_file);
2597 /* The default implementation of the asm_out.integer target hook. */
2599 bool
2600 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2601 unsigned int size ATTRIBUTE_UNUSED,
2602 int aligned_p ATTRIBUTE_UNUSED)
2604 const char *op = integer_asm_op (size, aligned_p);
2605 /* Avoid GAS bugs for large values. Specifically negative values whose
2606 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2607 if (size > UNITS_PER_WORD && size > POINTER_SIZE / BITS_PER_UNIT)
2608 return false;
2609 return op && (assemble_integer_with_op (op, x), true);
2612 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2613 the alignment of the integer in bits. Return 1 if we were able to output
2614 the constant, otherwise 0. We must be able to output the constant,
2615 if FORCE is nonzero. */
2617 bool
2618 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2620 int aligned_p;
2622 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2624 /* See if the target hook can handle this kind of object. */
2625 if (targetm.asm_out.integer (x, size, aligned_p))
2626 return true;
2628 /* If the object is a multi-byte one, try splitting it up. Split
2629 it into words it if is multi-word, otherwise split it into bytes. */
2630 if (size > 1)
2632 enum machine_mode omode, imode;
2633 unsigned int subalign;
2634 unsigned int subsize, i;
2635 enum mode_class mclass;
2637 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2638 subalign = MIN (align, subsize * BITS_PER_UNIT);
2639 if (GET_CODE (x) == CONST_FIXED)
2640 mclass = GET_MODE_CLASS (GET_MODE (x));
2641 else
2642 mclass = MODE_INT;
2644 omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0);
2645 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0);
2647 for (i = 0; i < size; i += subsize)
2649 rtx partial = simplify_subreg (omode, x, imode, i);
2650 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2651 break;
2653 if (i == size)
2654 return true;
2656 /* If we've printed some of it, but not all of it, there's no going
2657 back now. */
2658 gcc_assert (!i);
2661 gcc_assert (!force);
2663 return false;
2666 void
2667 assemble_real (REAL_VALUE_TYPE d, enum machine_mode mode, unsigned int align)
2669 long data[4] = {0, 0, 0, 0};
2670 int i;
2671 int bitsize, nelts, nunits, units_per;
2673 /* This is hairy. We have a quantity of known size. real_to_target
2674 will put it into an array of *host* longs, 32 bits per element
2675 (even if long is more than 32 bits). We need to determine the
2676 number of array elements that are occupied (nelts) and the number
2677 of *target* min-addressable units that will be occupied in the
2678 object file (nunits). We cannot assume that 32 divides the
2679 mode's bitsize (size * BITS_PER_UNIT) evenly.
2681 size * BITS_PER_UNIT is used here to make sure that padding bits
2682 (which might appear at either end of the value; real_to_target
2683 will include the padding bits in its output array) are included. */
2685 nunits = GET_MODE_SIZE (mode);
2686 bitsize = nunits * BITS_PER_UNIT;
2687 nelts = CEIL (bitsize, 32);
2688 units_per = 32 / BITS_PER_UNIT;
2690 real_to_target (data, &d, mode);
2692 /* Put out the first word with the specified alignment. */
2693 assemble_integer (GEN_INT (data[0]), MIN (nunits, units_per), align, 1);
2694 nunits -= units_per;
2696 /* Subsequent words need only 32-bit alignment. */
2697 align = min_align (align, 32);
2699 for (i = 1; i < nelts; i++)
2701 assemble_integer (GEN_INT (data[i]), MIN (nunits, units_per), align, 1);
2702 nunits -= units_per;
2706 /* Given an expression EXP with a constant value,
2707 reduce it to the sum of an assembler symbol and an integer.
2708 Store them both in the structure *VALUE.
2709 EXP must be reducible. */
2711 struct addr_const {
2712 rtx base;
2713 HOST_WIDE_INT offset;
2716 static void
2717 decode_addr_const (tree exp, struct addr_const *value)
2719 tree target = TREE_OPERAND (exp, 0);
2720 int offset = 0;
2721 rtx x;
2723 while (1)
2725 if (TREE_CODE (target) == COMPONENT_REF
2726 && tree_fits_shwi_p (byte_position (TREE_OPERAND (target, 1))))
2728 offset += int_byte_position (TREE_OPERAND (target, 1));
2729 target = TREE_OPERAND (target, 0);
2731 else if (TREE_CODE (target) == ARRAY_REF
2732 || TREE_CODE (target) == ARRAY_RANGE_REF)
2734 offset += (tree_to_uhwi (TYPE_SIZE_UNIT (TREE_TYPE (target)))
2735 * tree_to_shwi (TREE_OPERAND (target, 1)));
2736 target = TREE_OPERAND (target, 0);
2738 else if (TREE_CODE (target) == MEM_REF
2739 && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR)
2741 offset += mem_ref_offset (target).to_short_addr ();
2742 target = TREE_OPERAND (TREE_OPERAND (target, 0), 0);
2744 else if (TREE_CODE (target) == INDIRECT_REF
2745 && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR
2746 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0))
2747 == ADDR_EXPR)
2748 target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0);
2749 else
2750 break;
2753 switch (TREE_CODE (target))
2755 case VAR_DECL:
2756 case FUNCTION_DECL:
2757 x = DECL_RTL (target);
2758 break;
2760 case LABEL_DECL:
2761 x = gen_rtx_MEM (FUNCTION_MODE,
2762 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2763 break;
2765 case REAL_CST:
2766 case FIXED_CST:
2767 case STRING_CST:
2768 case COMPLEX_CST:
2769 case CONSTRUCTOR:
2770 case INTEGER_CST:
2771 x = output_constant_def (target, 1);
2772 break;
2774 default:
2775 gcc_unreachable ();
2778 gcc_assert (MEM_P (x));
2779 x = XEXP (x, 0);
2781 value->base = x;
2782 value->offset = offset;
2786 static GTY((param_is (struct constant_descriptor_tree)))
2787 htab_t const_desc_htab;
2789 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2791 /* Constant pool accessor function. */
2793 htab_t
2794 constant_pool_htab (void)
2796 return const_desc_htab;
2799 /* Compute a hash code for a constant expression. */
2801 static hashval_t
2802 const_desc_hash (const void *ptr)
2804 return ((const struct constant_descriptor_tree *)ptr)->hash;
2807 static hashval_t
2808 const_hash_1 (const tree exp)
2810 const char *p;
2811 hashval_t hi;
2812 int len, i;
2813 enum tree_code code = TREE_CODE (exp);
2815 /* Either set P and LEN to the address and len of something to hash and
2816 exit the switch or return a value. */
2818 switch (code)
2820 case INTEGER_CST:
2821 p = (char *) &TREE_INT_CST_ELT (exp, 0);
2822 len = TREE_INT_CST_NUNITS (exp) * sizeof (HOST_WIDE_INT);
2823 break;
2825 case REAL_CST:
2826 return real_hash (TREE_REAL_CST_PTR (exp));
2828 case FIXED_CST:
2829 return fixed_hash (TREE_FIXED_CST_PTR (exp));
2831 case STRING_CST:
2832 p = TREE_STRING_POINTER (exp);
2833 len = TREE_STRING_LENGTH (exp);
2834 break;
2836 case COMPLEX_CST:
2837 return (const_hash_1 (TREE_REALPART (exp)) * 5
2838 + const_hash_1 (TREE_IMAGPART (exp)));
2840 case VECTOR_CST:
2842 unsigned i;
2844 hi = 7 + VECTOR_CST_NELTS (exp);
2846 for (i = 0; i < VECTOR_CST_NELTS (exp); ++i)
2847 hi = hi * 563 + const_hash_1 (VECTOR_CST_ELT (exp, i));
2849 return hi;
2852 case CONSTRUCTOR:
2854 unsigned HOST_WIDE_INT idx;
2855 tree value;
2857 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2859 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
2860 if (value)
2861 hi = hi * 603 + const_hash_1 (value);
2863 return hi;
2866 case ADDR_EXPR:
2867 case FDESC_EXPR:
2869 struct addr_const value;
2871 decode_addr_const (exp, &value);
2872 switch (GET_CODE (value.base))
2874 case SYMBOL_REF:
2875 /* Don't hash the address of the SYMBOL_REF;
2876 only use the offset and the symbol name. */
2877 hi = value.offset;
2878 p = XSTR (value.base, 0);
2879 for (i = 0; p[i] != 0; i++)
2880 hi = ((hi * 613) + (unsigned) (p[i]));
2881 break;
2883 case LABEL_REF:
2884 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13;
2885 break;
2887 default:
2888 gcc_unreachable ();
2891 return hi;
2893 case PLUS_EXPR:
2894 case POINTER_PLUS_EXPR:
2895 case MINUS_EXPR:
2896 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2897 + const_hash_1 (TREE_OPERAND (exp, 1)));
2899 CASE_CONVERT:
2900 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
2902 default:
2903 /* A language specific constant. Just hash the code. */
2904 return code;
2907 /* Compute hashing function. */
2908 hi = len;
2909 for (i = 0; i < len; i++)
2910 hi = ((hi * 613) + (unsigned) (p[i]));
2912 return hi;
2915 /* Wrapper of compare_constant, for the htab interface. */
2916 static int
2917 const_desc_eq (const void *p1, const void *p2)
2919 const struct constant_descriptor_tree *const c1
2920 = (const struct constant_descriptor_tree *) p1;
2921 const struct constant_descriptor_tree *const c2
2922 = (const struct constant_descriptor_tree *) p2;
2923 if (c1->hash != c2->hash)
2924 return 0;
2925 return compare_constant (c1->value, c2->value);
2928 /* Compare t1 and t2, and return 1 only if they are known to result in
2929 the same bit pattern on output. */
2931 static int
2932 compare_constant (const tree t1, const tree t2)
2934 enum tree_code typecode;
2936 if (t1 == NULL_TREE)
2937 return t2 == NULL_TREE;
2938 if (t2 == NULL_TREE)
2939 return 0;
2941 if (TREE_CODE (t1) != TREE_CODE (t2))
2942 return 0;
2944 switch (TREE_CODE (t1))
2946 case INTEGER_CST:
2947 /* Integer constants are the same only if the same width of type. */
2948 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2949 return 0;
2950 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2951 return 0;
2952 return tree_int_cst_equal (t1, t2);
2954 case REAL_CST:
2955 /* Real constants are the same only if the same width of type. */
2956 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2957 return 0;
2959 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
2961 case FIXED_CST:
2962 /* Fixed constants are the same only if the same width of type. */
2963 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2964 return 0;
2966 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
2968 case STRING_CST:
2969 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2970 return 0;
2972 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
2973 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
2974 TREE_STRING_LENGTH (t1)));
2976 case COMPLEX_CST:
2977 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
2978 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
2980 case VECTOR_CST:
2982 unsigned i;
2984 if (VECTOR_CST_NELTS (t1) != VECTOR_CST_NELTS (t2))
2985 return 0;
2987 for (i = 0; i < VECTOR_CST_NELTS (t1); ++i)
2988 if (!compare_constant (VECTOR_CST_ELT (t1, i),
2989 VECTOR_CST_ELT (t2, i)))
2990 return 0;
2992 return 1;
2995 case CONSTRUCTOR:
2997 vec<constructor_elt, va_gc> *v1, *v2;
2998 unsigned HOST_WIDE_INT idx;
3000 typecode = TREE_CODE (TREE_TYPE (t1));
3001 if (typecode != TREE_CODE (TREE_TYPE (t2)))
3002 return 0;
3004 if (typecode == ARRAY_TYPE)
3006 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
3007 /* For arrays, check that the sizes all match. */
3008 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
3009 || size_1 == -1
3010 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
3011 return 0;
3013 else
3015 /* For record and union constructors, require exact type
3016 equality. */
3017 if (TREE_TYPE (t1) != TREE_TYPE (t2))
3018 return 0;
3021 v1 = CONSTRUCTOR_ELTS (t1);
3022 v2 = CONSTRUCTOR_ELTS (t2);
3023 if (vec_safe_length (v1) != vec_safe_length (v2))
3024 return 0;
3026 for (idx = 0; idx < vec_safe_length (v1); ++idx)
3028 constructor_elt *c1 = &(*v1)[idx];
3029 constructor_elt *c2 = &(*v2)[idx];
3031 /* Check that each value is the same... */
3032 if (!compare_constant (c1->value, c2->value))
3033 return 0;
3034 /* ... and that they apply to the same fields! */
3035 if (typecode == ARRAY_TYPE)
3037 if (!compare_constant (c1->index, c2->index))
3038 return 0;
3040 else
3042 if (c1->index != c2->index)
3043 return 0;
3047 return 1;
3050 case ADDR_EXPR:
3051 case FDESC_EXPR:
3053 struct addr_const value1, value2;
3054 enum rtx_code code;
3055 int ret;
3057 decode_addr_const (t1, &value1);
3058 decode_addr_const (t2, &value2);
3060 if (value1.offset != value2.offset)
3061 return 0;
3063 code = GET_CODE (value1.base);
3064 if (code != GET_CODE (value2.base))
3065 return 0;
3067 switch (code)
3069 case SYMBOL_REF:
3070 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3071 break;
3073 case LABEL_REF:
3074 ret = (CODE_LABEL_NUMBER (XEXP (value1.base, 0))
3075 == CODE_LABEL_NUMBER (XEXP (value2.base, 0)));
3076 break;
3078 default:
3079 gcc_unreachable ();
3081 return ret;
3084 case PLUS_EXPR:
3085 case POINTER_PLUS_EXPR:
3086 case MINUS_EXPR:
3087 case RANGE_EXPR:
3088 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3089 && compare_constant (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3091 CASE_CONVERT:
3092 case VIEW_CONVERT_EXPR:
3093 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3095 default:
3096 return 0;
3099 gcc_unreachable ();
3102 /* Make a copy of the whole tree structure for a constant. This
3103 handles the same types of nodes that compare_constant handles. */
3105 static tree
3106 copy_constant (tree exp)
3108 switch (TREE_CODE (exp))
3110 case ADDR_EXPR:
3111 /* For ADDR_EXPR, we do not want to copy the decl whose address
3112 is requested. We do want to copy constants though. */
3113 if (CONSTANT_CLASS_P (TREE_OPERAND (exp, 0)))
3114 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
3115 copy_constant (TREE_OPERAND (exp, 0)));
3116 else
3117 return copy_node (exp);
3119 case INTEGER_CST:
3120 case REAL_CST:
3121 case FIXED_CST:
3122 case STRING_CST:
3123 return copy_node (exp);
3125 case COMPLEX_CST:
3126 return build_complex (TREE_TYPE (exp),
3127 copy_constant (TREE_REALPART (exp)),
3128 copy_constant (TREE_IMAGPART (exp)));
3130 case PLUS_EXPR:
3131 case POINTER_PLUS_EXPR:
3132 case MINUS_EXPR:
3133 return build2 (TREE_CODE (exp), TREE_TYPE (exp),
3134 copy_constant (TREE_OPERAND (exp, 0)),
3135 copy_constant (TREE_OPERAND (exp, 1)));
3137 CASE_CONVERT:
3138 case VIEW_CONVERT_EXPR:
3139 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
3140 copy_constant (TREE_OPERAND (exp, 0)));
3142 case VECTOR_CST:
3143 return build_vector (TREE_TYPE (exp), VECTOR_CST_ELTS (exp));
3145 case CONSTRUCTOR:
3147 tree copy = copy_node (exp);
3148 vec<constructor_elt, va_gc> *v;
3149 unsigned HOST_WIDE_INT idx;
3150 tree purpose, value;
3152 vec_alloc (v, vec_safe_length (CONSTRUCTOR_ELTS (exp)));
3153 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (exp), idx, purpose, value)
3155 constructor_elt ce = {purpose, copy_constant (value)};
3156 v->quick_push (ce);
3158 CONSTRUCTOR_ELTS (copy) = v;
3159 return copy;
3162 default:
3163 gcc_unreachable ();
3167 /* Return the section into which constant EXP should be placed. */
3169 static section *
3170 get_constant_section (tree exp, unsigned int align)
3172 return targetm.asm_out.select_section (exp,
3173 compute_reloc_for_constant (exp),
3174 align);
3177 /* Return the size of constant EXP in bytes. */
3179 static HOST_WIDE_INT
3180 get_constant_size (tree exp)
3182 HOST_WIDE_INT size;
3184 size = int_size_in_bytes (TREE_TYPE (exp));
3185 if (TREE_CODE (exp) == STRING_CST)
3186 size = MAX (TREE_STRING_LENGTH (exp), size);
3187 return size;
3190 /* Subroutine of output_constant_def:
3191 No constant equal to EXP is known to have been output.
3192 Make a constant descriptor to enter EXP in the hash table.
3193 Assign the label number and construct RTL to refer to the
3194 constant's location in memory.
3195 Caller is responsible for updating the hash table. */
3197 static struct constant_descriptor_tree *
3198 build_constant_desc (tree exp)
3200 struct constant_descriptor_tree *desc;
3201 rtx symbol, rtl;
3202 char label[256];
3203 int labelno;
3204 tree decl;
3206 desc = ggc_alloc<constant_descriptor_tree> ();
3207 desc->value = copy_constant (exp);
3209 /* Create a string containing the label name, in LABEL. */
3210 labelno = const_labelno++;
3211 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3213 /* Construct the VAR_DECL associated with the constant. */
3214 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3215 TREE_TYPE (exp));
3216 DECL_ARTIFICIAL (decl) = 1;
3217 DECL_IGNORED_P (decl) = 1;
3218 TREE_READONLY (decl) = 1;
3219 TREE_STATIC (decl) = 1;
3220 TREE_ADDRESSABLE (decl) = 1;
3221 /* We don't set the RTL yet as this would cause varpool to assume that the
3222 variable is referenced. Moreover, it would just be dropped in LTO mode.
3223 Instead we set the flag that will be recognized in make_decl_rtl. */
3224 DECL_IN_CONSTANT_POOL (decl) = 1;
3225 DECL_INITIAL (decl) = desc->value;
3226 /* ??? CONSTANT_ALIGNMENT hasn't been updated for vector types on most
3227 architectures so use DATA_ALIGNMENT as well, except for strings. */
3228 if (TREE_CODE (exp) == STRING_CST)
3230 #ifdef CONSTANT_ALIGNMENT
3231 DECL_ALIGN (decl) = CONSTANT_ALIGNMENT (exp, DECL_ALIGN (decl));
3232 #endif
3234 else
3235 align_variable (decl, 0);
3237 /* Now construct the SYMBOL_REF and the MEM. */
3238 if (use_object_blocks_p ())
3240 section *sect = get_constant_section (exp, DECL_ALIGN (decl));
3241 symbol = create_block_symbol (ggc_strdup (label),
3242 get_block_for_section (sect), -1);
3244 else
3245 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3246 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3247 SET_SYMBOL_REF_DECL (symbol, decl);
3248 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3250 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3251 set_mem_attributes (rtl, exp, 1);
3252 set_mem_alias_set (rtl, 0);
3253 set_mem_alias_set (rtl, const_alias_set);
3255 /* We cannot share RTX'es in pool entries.
3256 Mark this piece of RTL as required for unsharing. */
3257 RTX_FLAG (rtl, used) = 1;
3259 /* Set flags or add text to the name to record information, such as
3260 that it is a local symbol. If the name is changed, the macro
3261 ASM_OUTPUT_LABELREF will have to know how to strip this
3262 information. This call might invalidate our local variable
3263 SYMBOL; we can't use it afterward. */
3264 targetm.encode_section_info (exp, rtl, true);
3266 desc->rtl = rtl;
3268 return desc;
3271 /* Return an rtx representing a reference to constant data in memory
3272 for the constant expression EXP.
3274 If assembler code for such a constant has already been output,
3275 return an rtx to refer to it.
3276 Otherwise, output such a constant in memory
3277 and generate an rtx for it.
3279 If DEFER is nonzero, this constant can be deferred and output only
3280 if referenced in the function after all optimizations.
3282 `const_desc_table' records which constants already have label strings. */
3285 output_constant_def (tree exp, int defer)
3287 struct constant_descriptor_tree *desc;
3288 struct constant_descriptor_tree key;
3289 void **loc;
3291 /* Look up EXP in the table of constant descriptors. If we didn't find
3292 it, create a new one. */
3293 key.value = exp;
3294 key.hash = const_hash_1 (exp);
3295 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3297 desc = (struct constant_descriptor_tree *) *loc;
3298 if (desc == 0)
3300 desc = build_constant_desc (exp);
3301 desc->hash = key.hash;
3302 *loc = desc;
3305 maybe_output_constant_def_contents (desc, defer);
3306 return desc->rtl;
3309 /* Subroutine of output_constant_def: Decide whether or not we need to
3310 output the constant DESC now, and if so, do it. */
3311 static void
3312 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3313 int defer)
3315 rtx symbol = XEXP (desc->rtl, 0);
3316 tree exp = desc->value;
3318 if (flag_syntax_only)
3319 return;
3321 if (TREE_ASM_WRITTEN (exp))
3322 /* Already output; don't do it again. */
3323 return;
3325 /* We can always defer constants as long as the context allows
3326 doing so. */
3327 if (defer)
3329 /* Increment n_deferred_constants if it exists. It needs to be at
3330 least as large as the number of constants actually referred to
3331 by the function. If it's too small we'll stop looking too early
3332 and fail to emit constants; if it's too large we'll only look
3333 through the entire function when we could have stopped earlier. */
3334 if (cfun)
3335 n_deferred_constants++;
3336 return;
3339 output_constant_def_contents (symbol);
3342 /* Subroutine of output_constant_def_contents. Output the definition
3343 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3344 constant's alignment in bits. */
3346 static void
3347 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3349 HOST_WIDE_INT size;
3351 size = get_constant_size (exp);
3353 /* Do any machine/system dependent processing of the constant. */
3354 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3356 /* Output the value of EXP. */
3357 output_constant (exp, size, align);
3360 /* We must output the constant data referred to by SYMBOL; do so. */
3362 static void
3363 output_constant_def_contents (rtx symbol)
3365 tree decl = SYMBOL_REF_DECL (symbol);
3366 tree exp = DECL_INITIAL (decl);
3367 unsigned int align;
3368 bool asan_protected = false;
3370 /* Make sure any other constants whose addresses appear in EXP
3371 are assigned label numbers. */
3372 output_addressed_constants (exp);
3374 /* We are no longer deferring this constant. */
3375 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3377 if ((flag_sanitize & SANITIZE_ADDRESS)
3378 && TREE_CODE (exp) == STRING_CST
3379 && asan_protect_global (exp))
3381 asan_protected = true;
3382 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
3383 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
3386 /* If the constant is part of an object block, make sure that the
3387 decl has been positioned within its block, but do not write out
3388 its definition yet. output_object_blocks will do that later. */
3389 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3390 place_block_symbol (symbol);
3391 else
3393 align = DECL_ALIGN (decl);
3394 switch_to_section (get_constant_section (exp, align));
3395 if (align > BITS_PER_UNIT)
3396 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3397 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3398 if (asan_protected)
3400 HOST_WIDE_INT size = get_constant_size (exp);
3401 assemble_zeros (asan_red_zone_size (size));
3406 /* Look up EXP in the table of constant descriptors. Return the rtl
3407 if it has been emitted, else null. */
3410 lookup_constant_def (tree exp)
3412 struct constant_descriptor_tree *desc;
3413 struct constant_descriptor_tree key;
3415 key.value = exp;
3416 key.hash = const_hash_1 (exp);
3417 desc = (struct constant_descriptor_tree *)
3418 htab_find_with_hash (const_desc_htab, &key, key.hash);
3420 return (desc ? desc->rtl : NULL_RTX);
3423 /* Return a tree representing a reference to constant data in memory
3424 for the constant expression EXP.
3426 This is the counterpart of output_constant_def at the Tree level. */
3428 tree
3429 tree_output_constant_def (tree exp)
3431 struct constant_descriptor_tree *desc, key;
3432 void **loc;
3433 tree decl;
3435 /* Look up EXP in the table of constant descriptors. If we didn't find
3436 it, create a new one. */
3437 key.value = exp;
3438 key.hash = const_hash_1 (exp);
3439 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3441 desc = (struct constant_descriptor_tree *) *loc;
3442 if (desc == 0)
3444 desc = build_constant_desc (exp);
3445 desc->hash = key.hash;
3446 *loc = desc;
3449 decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3450 varpool_finalize_decl (decl);
3451 return decl;
3454 /* Used in the hash tables to avoid outputting the same constant
3455 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3456 are output once per function, not once per file. */
3457 /* ??? Only a few targets need per-function constant pools. Most
3458 can use one per-file pool. Should add a targetm bit to tell the
3459 difference. */
3461 struct GTY(()) rtx_constant_pool {
3462 /* Pointers to first and last constant in pool, as ordered by offset. */
3463 struct constant_descriptor_rtx *first;
3464 struct constant_descriptor_rtx *last;
3466 /* Hash facility for making memory-constants from constant rtl-expressions.
3467 It is used on RISC machines where immediate integer arguments and
3468 constant addresses are restricted so that such constants must be stored
3469 in memory. */
3470 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_htab;
3472 /* Current offset in constant pool (does not include any
3473 machine-specific header). */
3474 HOST_WIDE_INT offset;
3477 struct GTY((chain_next ("%h.next"))) constant_descriptor_rtx {
3478 struct constant_descriptor_rtx *next;
3479 rtx mem;
3480 rtx sym;
3481 rtx constant;
3482 HOST_WIDE_INT offset;
3483 hashval_t hash;
3484 enum machine_mode mode;
3485 unsigned int align;
3486 int labelno;
3487 int mark;
3490 /* Hash and compare functions for const_rtx_htab. */
3492 static hashval_t
3493 const_desc_rtx_hash (const void *ptr)
3495 const struct constant_descriptor_rtx *const desc
3496 = (const struct constant_descriptor_rtx *) ptr;
3497 return desc->hash;
3500 static int
3501 const_desc_rtx_eq (const void *a, const void *b)
3503 const struct constant_descriptor_rtx *const x
3504 = (const struct constant_descriptor_rtx *) a;
3505 const struct constant_descriptor_rtx *const y
3506 = (const struct constant_descriptor_rtx *) b;
3508 if (x->mode != y->mode)
3509 return 0;
3510 return rtx_equal_p (x->constant, y->constant);
3513 /* This is the worker function for const_rtx_hash, called via for_each_rtx. */
3515 static int
3516 const_rtx_hash_1 (rtx *xp, void *data)
3518 unsigned HOST_WIDE_INT hwi;
3519 enum machine_mode mode;
3520 enum rtx_code code;
3521 hashval_t h, *hp;
3522 rtx x;
3523 int i;
3525 x = *xp;
3526 code = GET_CODE (x);
3527 mode = GET_MODE (x);
3528 h = (hashval_t) code * 1048573 + mode;
3530 switch (code)
3532 case CONST_INT:
3533 hwi = INTVAL (x);
3535 fold_hwi:
3537 int shift = sizeof (hashval_t) * CHAR_BIT;
3538 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3540 h ^= (hashval_t) hwi;
3541 for (i = 1; i < n; ++i)
3543 hwi >>= shift;
3544 h ^= (hashval_t) hwi;
3547 break;
3549 case CONST_WIDE_INT:
3550 hwi = GET_MODE_PRECISION (mode);
3552 for (i = 0; i < CONST_WIDE_INT_NUNITS (x); i++)
3553 hwi ^= CONST_WIDE_INT_ELT (x, i);
3554 goto fold_hwi;
3557 case CONST_DOUBLE:
3558 if (TARGET_SUPPORTS_WIDE_INT == 0 && mode == VOIDmode)
3560 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3561 goto fold_hwi;
3563 else
3564 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3565 break;
3567 case CONST_FIXED:
3568 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3569 break;
3571 case CONST_VECTOR:
3573 int i;
3574 for (i = XVECLEN (x, 0); i-- > 0; )
3575 h = h * 251 + const_rtx_hash_1 (&XVECEXP (x, 0, i), data);
3577 break;
3579 case SYMBOL_REF:
3580 h ^= htab_hash_string (XSTR (x, 0));
3581 break;
3583 case LABEL_REF:
3584 h = h * 251 + CODE_LABEL_NUMBER (XEXP (x, 0));
3585 break;
3587 case UNSPEC:
3588 case UNSPEC_VOLATILE:
3589 h = h * 251 + XINT (x, 1);
3590 break;
3592 default:
3593 break;
3596 hp = (hashval_t *) data;
3597 *hp = *hp * 509 + h;
3598 return 0;
3601 /* Compute a hash value for X, which should be a constant. */
3603 static hashval_t
3604 const_rtx_hash (rtx x)
3606 hashval_t h = 0;
3607 for_each_rtx (&x, const_rtx_hash_1, &h);
3608 return h;
3612 /* Create and return a new rtx constant pool. */
3614 static struct rtx_constant_pool *
3615 create_constant_pool (void)
3617 struct rtx_constant_pool *pool;
3619 pool = ggc_alloc<rtx_constant_pool> ();
3620 pool->const_rtx_htab = htab_create_ggc (31, const_desc_rtx_hash,
3621 const_desc_rtx_eq, NULL);
3622 pool->first = NULL;
3623 pool->last = NULL;
3624 pool->offset = 0;
3625 return pool;
3628 /* Initialize constant pool hashing for a new function. */
3630 void
3631 init_varasm_status (void)
3633 crtl->varasm.pool = create_constant_pool ();
3634 crtl->varasm.deferred_constants = 0;
3637 /* Given a MINUS expression, simplify it if both sides
3638 include the same symbol. */
3641 simplify_subtraction (rtx x)
3643 rtx r = simplify_rtx (x);
3644 return r ? r : x;
3647 /* Given a constant rtx X, make (or find) a memory constant for its value
3648 and return a MEM rtx to refer to it in memory. */
3651 force_const_mem (enum machine_mode mode, rtx x)
3653 struct constant_descriptor_rtx *desc, tmp;
3654 struct rtx_constant_pool *pool;
3655 char label[256];
3656 rtx def, symbol;
3657 hashval_t hash;
3658 unsigned int align;
3659 void **slot;
3661 /* If we're not allowed to drop X into the constant pool, don't. */
3662 if (targetm.cannot_force_const_mem (mode, x))
3663 return NULL_RTX;
3665 /* Record that this function has used a constant pool entry. */
3666 crtl->uses_const_pool = 1;
3668 /* Decide which pool to use. */
3669 pool = (targetm.use_blocks_for_constant_p (mode, x)
3670 ? shared_constant_pool
3671 : crtl->varasm.pool);
3673 /* Lookup the value in the hashtable. */
3674 tmp.constant = x;
3675 tmp.mode = mode;
3676 hash = const_rtx_hash (x);
3677 slot = htab_find_slot_with_hash (pool->const_rtx_htab, &tmp, hash, INSERT);
3678 desc = (struct constant_descriptor_rtx *) *slot;
3680 /* If the constant was already present, return its memory. */
3681 if (desc)
3682 return copy_rtx (desc->mem);
3684 /* Otherwise, create a new descriptor. */
3685 desc = ggc_alloc<constant_descriptor_rtx> ();
3686 *slot = desc;
3688 /* Align the location counter as required by EXP's data type. */
3689 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3690 #ifdef CONSTANT_ALIGNMENT
3692 tree type = lang_hooks.types.type_for_mode (mode, 0);
3693 if (type != NULL_TREE)
3694 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3696 #endif
3698 pool->offset += (align / BITS_PER_UNIT) - 1;
3699 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3701 desc->next = NULL;
3702 desc->constant = copy_rtx (tmp.constant);
3703 desc->offset = pool->offset;
3704 desc->hash = hash;
3705 desc->mode = mode;
3706 desc->align = align;
3707 desc->labelno = const_labelno;
3708 desc->mark = 0;
3710 pool->offset += GET_MODE_SIZE (mode);
3711 if (pool->last)
3712 pool->last->next = desc;
3713 else
3714 pool->first = pool->last = desc;
3715 pool->last = desc;
3717 /* Create a string containing the label name, in LABEL. */
3718 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3719 ++const_labelno;
3721 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3722 the constants pool. */
3723 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3725 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3726 symbol = create_block_symbol (ggc_strdup (label),
3727 get_block_for_section (sect), -1);
3729 else
3730 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3731 desc->sym = symbol;
3732 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3733 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3734 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3736 /* Construct the MEM. */
3737 desc->mem = def = gen_const_mem (mode, symbol);
3738 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3739 set_mem_align (def, align);
3741 /* If we're dropping a label to the constant pool, make sure we
3742 don't delete it. */
3743 if (GET_CODE (x) == LABEL_REF)
3744 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3746 return copy_rtx (def);
3749 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3752 get_pool_constant (rtx addr)
3754 return SYMBOL_REF_CONSTANT (addr)->constant;
3757 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3758 and whether it has been output or not. */
3761 get_pool_constant_mark (rtx addr, bool *pmarked)
3763 struct constant_descriptor_rtx *desc;
3765 desc = SYMBOL_REF_CONSTANT (addr);
3766 *pmarked = (desc->mark != 0);
3767 return desc->constant;
3770 /* Similar, return the mode. */
3772 enum machine_mode
3773 get_pool_mode (const_rtx addr)
3775 return SYMBOL_REF_CONSTANT (addr)->mode;
3778 /* Return the size of the constant pool. */
3781 get_pool_size (void)
3783 return crtl->varasm.pool->offset;
3786 /* Worker function for output_constant_pool_1. Emit assembly for X
3787 in MODE with known alignment ALIGN. */
3789 static void
3790 output_constant_pool_2 (enum machine_mode mode, rtx x, unsigned int align)
3792 switch (GET_MODE_CLASS (mode))
3794 case MODE_FLOAT:
3795 case MODE_DECIMAL_FLOAT:
3797 REAL_VALUE_TYPE r;
3799 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3800 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3801 assemble_real (r, mode, align);
3802 break;
3805 case MODE_INT:
3806 case MODE_PARTIAL_INT:
3807 case MODE_FRACT:
3808 case MODE_UFRACT:
3809 case MODE_ACCUM:
3810 case MODE_UACCUM:
3811 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3812 break;
3814 case MODE_VECTOR_FLOAT:
3815 case MODE_VECTOR_INT:
3816 case MODE_VECTOR_FRACT:
3817 case MODE_VECTOR_UFRACT:
3818 case MODE_VECTOR_ACCUM:
3819 case MODE_VECTOR_UACCUM:
3821 int i, units;
3822 enum machine_mode submode = GET_MODE_INNER (mode);
3823 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3825 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3826 units = CONST_VECTOR_NUNITS (x);
3828 for (i = 0; i < units; i++)
3830 rtx elt = CONST_VECTOR_ELT (x, i);
3831 output_constant_pool_2 (submode, elt, i ? subalign : align);
3834 break;
3836 default:
3837 gcc_unreachable ();
3841 /* Worker function for output_constant_pool. Emit constant DESC,
3842 giving it ALIGN bits of alignment. */
3844 static void
3845 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3846 unsigned int align)
3848 rtx x, tmp;
3850 x = desc->constant;
3852 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3853 whose CODE_LABEL has been deleted. This can occur if a jump table
3854 is eliminated by optimization. If so, write a constant of zero
3855 instead. Note that this can also happen by turning the
3856 CODE_LABEL into a NOTE. */
3857 /* ??? This seems completely and utterly wrong. Certainly it's
3858 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3859 functioning even with INSN_DELETED_P and friends. */
3861 tmp = x;
3862 switch (GET_CODE (tmp))
3864 case CONST:
3865 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3866 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
3867 break;
3868 tmp = XEXP (XEXP (tmp, 0), 0);
3869 /* FALLTHRU */
3871 case LABEL_REF:
3872 tmp = XEXP (tmp, 0);
3873 gcc_assert (!INSN_DELETED_P (tmp));
3874 gcc_assert (!NOTE_P (tmp)
3875 || NOTE_KIND (tmp) != NOTE_INSN_DELETED);
3876 break;
3878 default:
3879 break;
3882 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3883 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3884 align, desc->labelno, done);
3885 #endif
3887 assemble_align (align);
3889 /* Output the label. */
3890 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3892 /* Output the data. */
3893 output_constant_pool_2 (desc->mode, x, align);
3895 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3896 sections have proper size. */
3897 if (align > GET_MODE_BITSIZE (desc->mode)
3898 && in_section
3899 && (in_section->common.flags & SECTION_MERGE))
3900 assemble_align (align);
3902 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3903 done:
3904 #endif
3905 return;
3908 /* Given a SYMBOL_REF CURRENT_RTX, mark it and all constants it refers
3909 to as used. Emit referenced deferred strings. This function can
3910 be used with for_each_rtx to mark all SYMBOL_REFs in an rtx. */
3912 static int
3913 mark_constant (rtx *current_rtx, void *data ATTRIBUTE_UNUSED)
3915 rtx x = *current_rtx;
3917 if (x == NULL_RTX || GET_CODE (x) != SYMBOL_REF)
3918 return 0;
3920 if (CONSTANT_POOL_ADDRESS_P (x))
3922 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
3923 if (desc->mark == 0)
3925 desc->mark = 1;
3926 for_each_rtx (&desc->constant, mark_constant, NULL);
3929 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3931 tree decl = SYMBOL_REF_DECL (x);
3932 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
3934 n_deferred_constants--;
3935 output_constant_def_contents (x);
3939 return -1;
3942 /* Look through appropriate parts of INSN, marking all entries in the
3943 constant pool which are actually being used. Entries that are only
3944 referenced by other constants are also marked as used. Emit
3945 deferred strings that are used. */
3947 static void
3948 mark_constants (rtx insn)
3950 if (!INSN_P (insn))
3951 return;
3953 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3954 insns, not any notes that may be attached. We don't want to mark
3955 a constant just because it happens to appear in a REG_EQUIV note. */
3956 if (GET_CODE (PATTERN (insn)) == SEQUENCE)
3958 rtx seq = PATTERN (insn);
3959 int i, n = XVECLEN (seq, 0);
3960 for (i = 0; i < n; ++i)
3962 rtx subinsn = XVECEXP (seq, 0, i);
3963 if (INSN_P (subinsn))
3964 for_each_rtx (&PATTERN (subinsn), mark_constant, NULL);
3967 else
3968 for_each_rtx (&PATTERN (insn), mark_constant, NULL);
3971 /* Look through the instructions for this function, and mark all the
3972 entries in POOL which are actually being used. Emit deferred constants
3973 which have indeed been used. */
3975 static void
3976 mark_constant_pool (void)
3978 rtx insn;
3980 if (!crtl->uses_const_pool && n_deferred_constants == 0)
3981 return;
3983 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3984 mark_constants (insn);
3987 /* Write all the constants in POOL. */
3989 static void
3990 output_constant_pool_contents (struct rtx_constant_pool *pool)
3992 struct constant_descriptor_rtx *desc;
3994 for (desc = pool->first; desc ; desc = desc->next)
3995 if (desc->mark)
3997 /* If the constant is part of an object_block, make sure that
3998 the constant has been positioned within its block, but do not
3999 write out its definition yet. output_object_blocks will do
4000 that later. */
4001 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
4002 && SYMBOL_REF_BLOCK (desc->sym))
4003 place_block_symbol (desc->sym);
4004 else
4006 switch_to_section (targetm.asm_out.select_rtx_section
4007 (desc->mode, desc->constant, desc->align));
4008 output_constant_pool_1 (desc, desc->align);
4013 /* Mark all constants that are used in the current function, then write
4014 out the function's private constant pool. */
4016 static void
4017 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
4018 tree fndecl ATTRIBUTE_UNUSED)
4020 struct rtx_constant_pool *pool = crtl->varasm.pool;
4022 /* It is possible for gcc to call force_const_mem and then to later
4023 discard the instructions which refer to the constant. In such a
4024 case we do not need to output the constant. */
4025 mark_constant_pool ();
4027 #ifdef ASM_OUTPUT_POOL_PROLOGUE
4028 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
4029 #endif
4031 output_constant_pool_contents (pool);
4033 #ifdef ASM_OUTPUT_POOL_EPILOGUE
4034 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
4035 #endif
4038 /* Write the contents of the shared constant pool. */
4040 void
4041 output_shared_constant_pool (void)
4043 output_constant_pool_contents (shared_constant_pool);
4046 /* Determine what kind of relocations EXP may need. */
4049 compute_reloc_for_constant (tree exp)
4051 int reloc = 0, reloc2;
4052 tree tem;
4054 switch (TREE_CODE (exp))
4056 case ADDR_EXPR:
4057 case FDESC_EXPR:
4058 /* Go inside any operations that get_inner_reference can handle and see
4059 if what's inside is a constant: no need to do anything here for
4060 addresses of variables or functions. */
4061 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4062 tem = TREE_OPERAND (tem, 0))
4065 if (TREE_CODE (tem) == MEM_REF
4066 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4068 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4069 break;
4072 if (!targetm.binds_local_p (tem))
4073 reloc |= 2;
4074 else
4075 reloc |= 1;
4076 break;
4078 case PLUS_EXPR:
4079 case POINTER_PLUS_EXPR:
4080 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4081 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4082 break;
4084 case MINUS_EXPR:
4085 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4086 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4087 /* The difference of two local labels is computable at link time. */
4088 if (reloc == 1 && reloc2 == 1)
4089 reloc = 0;
4090 else
4091 reloc |= reloc2;
4092 break;
4094 CASE_CONVERT:
4095 case VIEW_CONVERT_EXPR:
4096 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4097 break;
4099 case CONSTRUCTOR:
4101 unsigned HOST_WIDE_INT idx;
4102 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4103 if (tem != 0)
4104 reloc |= compute_reloc_for_constant (tem);
4106 break;
4108 default:
4109 break;
4111 return reloc;
4114 /* Find all the constants whose addresses are referenced inside of EXP,
4115 and make sure assembler code with a label has been output for each one.
4116 Indicate whether an ADDR_EXPR has been encountered. */
4118 static void
4119 output_addressed_constants (tree exp)
4121 tree tem;
4123 switch (TREE_CODE (exp))
4125 case ADDR_EXPR:
4126 case FDESC_EXPR:
4127 /* Go inside any operations that get_inner_reference can handle and see
4128 if what's inside is a constant: no need to do anything here for
4129 addresses of variables or functions. */
4130 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4131 tem = TREE_OPERAND (tem, 0))
4134 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4135 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4136 tem = DECL_INITIAL (tem);
4138 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4139 output_constant_def (tem, 0);
4141 if (TREE_CODE (tem) == MEM_REF)
4142 output_addressed_constants (TREE_OPERAND (tem, 0));
4143 break;
4145 case PLUS_EXPR:
4146 case POINTER_PLUS_EXPR:
4147 case MINUS_EXPR:
4148 output_addressed_constants (TREE_OPERAND (exp, 1));
4149 /* Fall through. */
4151 CASE_CONVERT:
4152 case VIEW_CONVERT_EXPR:
4153 output_addressed_constants (TREE_OPERAND (exp, 0));
4154 break;
4156 case CONSTRUCTOR:
4158 unsigned HOST_WIDE_INT idx;
4159 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4160 if (tem != 0)
4161 output_addressed_constants (tem);
4163 break;
4165 default:
4166 break;
4170 /* Whether a constructor CTOR is a valid static constant initializer if all
4171 its elements are. This used to be internal to initializer_constant_valid_p
4172 and has been exposed to let other functions like categorize_ctor_elements
4173 evaluate the property while walking a constructor for other purposes. */
4175 bool
4176 constructor_static_from_elts_p (const_tree ctor)
4178 return (TREE_CONSTANT (ctor)
4179 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4180 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4181 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4184 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4185 tree *cache);
4187 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4188 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4189 which are valid when ENDTYPE is an integer of any size; in
4190 particular, this does not accept a pointer minus a constant. This
4191 returns null_pointer_node if the VALUE is an absolute constant
4192 which can be used to initialize a static variable. Otherwise it
4193 returns NULL. */
4195 static tree
4196 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4198 tree op0, op1;
4200 if (!INTEGRAL_TYPE_P (endtype))
4201 return NULL_TREE;
4203 op0 = TREE_OPERAND (value, 0);
4204 op1 = TREE_OPERAND (value, 1);
4206 /* Like STRIP_NOPS except allow the operand mode to widen. This
4207 works around a feature of fold that simplifies (int)(p1 - p2) to
4208 ((int)p1 - (int)p2) under the theory that the narrower operation
4209 is cheaper. */
4211 while (CONVERT_EXPR_P (op0)
4212 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4214 tree inner = TREE_OPERAND (op0, 0);
4215 if (inner == error_mark_node
4216 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4217 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
4218 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4219 break;
4220 op0 = inner;
4223 while (CONVERT_EXPR_P (op1)
4224 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4226 tree inner = TREE_OPERAND (op1, 0);
4227 if (inner == error_mark_node
4228 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4229 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
4230 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4231 break;
4232 op1 = inner;
4235 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4236 if (!op0)
4237 return NULL_TREE;
4239 op1 = initializer_constant_valid_p_1 (op1, endtype,
4240 cache ? cache + 2 : NULL);
4241 /* Both initializers must be known. */
4242 if (op1)
4244 if (op0 == op1
4245 && (op0 == null_pointer_node
4246 || TREE_CODE (value) == MINUS_EXPR))
4247 return null_pointer_node;
4249 /* Support differences between labels. */
4250 if (TREE_CODE (op0) == LABEL_DECL
4251 && TREE_CODE (op1) == LABEL_DECL)
4252 return null_pointer_node;
4254 if (TREE_CODE (op0) == STRING_CST
4255 && TREE_CODE (op1) == STRING_CST
4256 && operand_equal_p (op0, op1, 1))
4257 return null_pointer_node;
4260 return NULL_TREE;
4263 /* Helper function of initializer_constant_valid_p.
4264 Return nonzero if VALUE is a valid constant-valued expression
4265 for use in initializing a static variable; one that can be an
4266 element of a "constant" initializer.
4268 Return null_pointer_node if the value is absolute;
4269 if it is relocatable, return the variable that determines the relocation.
4270 We assume that VALUE has been folded as much as possible;
4271 therefore, we do not need to check for such things as
4272 arithmetic-combinations of integers.
4274 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4276 static tree
4277 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4279 tree ret;
4281 switch (TREE_CODE (value))
4283 case CONSTRUCTOR:
4284 if (constructor_static_from_elts_p (value))
4286 unsigned HOST_WIDE_INT idx;
4287 tree elt;
4288 bool absolute = true;
4290 if (cache && cache[0] == value)
4291 return cache[1];
4292 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4294 tree reloc;
4295 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4296 NULL);
4297 if (!reloc)
4299 if (cache)
4301 cache[0] = value;
4302 cache[1] = NULL_TREE;
4304 return NULL_TREE;
4306 if (reloc != null_pointer_node)
4307 absolute = false;
4309 /* For a non-absolute relocation, there is no single
4310 variable that can be "the variable that determines the
4311 relocation." */
4312 if (cache)
4314 cache[0] = value;
4315 cache[1] = absolute ? null_pointer_node : error_mark_node;
4317 return absolute ? null_pointer_node : error_mark_node;
4320 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4322 case INTEGER_CST:
4323 case VECTOR_CST:
4324 case REAL_CST:
4325 case FIXED_CST:
4326 case STRING_CST:
4327 case COMPLEX_CST:
4328 return null_pointer_node;
4330 case ADDR_EXPR:
4331 case FDESC_EXPR:
4333 tree op0 = staticp (TREE_OPERAND (value, 0));
4334 if (op0)
4336 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4337 to be a constant, this is old-skool offsetof-like nonsense. */
4338 if (TREE_CODE (op0) == INDIRECT_REF
4339 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4340 return null_pointer_node;
4341 /* Taking the address of a nested function involves a trampoline,
4342 unless we don't need or want one. */
4343 if (TREE_CODE (op0) == FUNCTION_DECL
4344 && DECL_STATIC_CHAIN (op0)
4345 && !TREE_NO_TRAMPOLINE (value))
4346 return NULL_TREE;
4347 /* "&{...}" requires a temporary to hold the constructed
4348 object. */
4349 if (TREE_CODE (op0) == CONSTRUCTOR)
4350 return NULL_TREE;
4352 return op0;
4355 case NON_LVALUE_EXPR:
4356 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4357 endtype, cache);
4359 case VIEW_CONVERT_EXPR:
4361 tree src = TREE_OPERAND (value, 0);
4362 tree src_type = TREE_TYPE (src);
4363 tree dest_type = TREE_TYPE (value);
4365 /* Allow view-conversions from aggregate to non-aggregate type only
4366 if the bit pattern is fully preserved afterwards; otherwise, the
4367 RTL expander won't be able to apply a subsequent transformation
4368 to the underlying constructor. */
4369 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4371 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4372 return initializer_constant_valid_p_1 (src, endtype, cache);
4373 else
4374 return NULL_TREE;
4377 /* Allow all other kinds of view-conversion. */
4378 return initializer_constant_valid_p_1 (src, endtype, cache);
4381 CASE_CONVERT:
4383 tree src = TREE_OPERAND (value, 0);
4384 tree src_type = TREE_TYPE (src);
4385 tree dest_type = TREE_TYPE (value);
4387 /* Allow conversions between pointer types, floating-point
4388 types, and offset types. */
4389 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4390 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4391 || (TREE_CODE (dest_type) == OFFSET_TYPE
4392 && TREE_CODE (src_type) == OFFSET_TYPE))
4393 return initializer_constant_valid_p_1 (src, endtype, cache);
4395 /* Allow length-preserving conversions between integer types. */
4396 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4397 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4398 return initializer_constant_valid_p_1 (src, endtype, cache);
4400 /* Allow conversions between other integer types only if
4401 explicit value. */
4402 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type))
4404 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4405 if (inner == null_pointer_node)
4406 return null_pointer_node;
4407 break;
4410 /* Allow (int) &foo provided int is as wide as a pointer. */
4411 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4412 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4413 return initializer_constant_valid_p_1 (src, endtype, cache);
4415 /* Likewise conversions from int to pointers, but also allow
4416 conversions from 0. */
4417 if ((POINTER_TYPE_P (dest_type)
4418 || TREE_CODE (dest_type) == OFFSET_TYPE)
4419 && INTEGRAL_TYPE_P (src_type))
4421 if (TREE_CODE (src) == INTEGER_CST
4422 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4423 return null_pointer_node;
4424 if (integer_zerop (src))
4425 return null_pointer_node;
4426 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4427 return initializer_constant_valid_p_1 (src, endtype, cache);
4430 /* Allow conversions to struct or union types if the value
4431 inside is okay. */
4432 if (TREE_CODE (dest_type) == RECORD_TYPE
4433 || TREE_CODE (dest_type) == UNION_TYPE)
4434 return initializer_constant_valid_p_1 (src, endtype, cache);
4436 break;
4438 case POINTER_PLUS_EXPR:
4439 case PLUS_EXPR:
4440 /* Any valid floating-point constants will have been folded by now;
4441 with -frounding-math we hit this with addition of two constants. */
4442 if (TREE_CODE (endtype) == REAL_TYPE)
4443 return NULL_TREE;
4444 if (cache && cache[0] == value)
4445 return cache[1];
4446 if (! INTEGRAL_TYPE_P (endtype)
4447 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4449 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4450 tree valid0
4451 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4452 endtype, ncache);
4453 tree valid1
4454 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4455 endtype, ncache + 2);
4456 /* If either term is absolute, use the other term's relocation. */
4457 if (valid0 == null_pointer_node)
4458 ret = valid1;
4459 else if (valid1 == null_pointer_node)
4460 ret = valid0;
4461 /* Support narrowing pointer differences. */
4462 else
4463 ret = narrowing_initializer_constant_valid_p (value, endtype,
4464 ncache);
4466 else
4467 /* Support narrowing pointer differences. */
4468 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4469 if (cache)
4471 cache[0] = value;
4472 cache[1] = ret;
4474 return ret;
4476 case MINUS_EXPR:
4477 if (TREE_CODE (endtype) == REAL_TYPE)
4478 return NULL_TREE;
4479 if (cache && cache[0] == value)
4480 return cache[1];
4481 if (! INTEGRAL_TYPE_P (endtype)
4482 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4484 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4485 tree valid0
4486 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4487 endtype, ncache);
4488 tree valid1
4489 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4490 endtype, ncache + 2);
4491 /* Win if second argument is absolute. */
4492 if (valid1 == null_pointer_node)
4493 ret = valid0;
4494 /* Win if both arguments have the same relocation.
4495 Then the value is absolute. */
4496 else if (valid0 == valid1 && valid0 != 0)
4497 ret = null_pointer_node;
4498 /* Since GCC guarantees that string constants are unique in the
4499 generated code, a subtraction between two copies of the same
4500 constant string is absolute. */
4501 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4502 && valid1 && TREE_CODE (valid1) == STRING_CST
4503 && operand_equal_p (valid0, valid1, 1))
4504 ret = null_pointer_node;
4505 /* Support narrowing differences. */
4506 else
4507 ret = narrowing_initializer_constant_valid_p (value, endtype,
4508 ncache);
4510 else
4511 /* Support narrowing differences. */
4512 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4513 if (cache)
4515 cache[0] = value;
4516 cache[1] = ret;
4518 return ret;
4520 default:
4521 break;
4524 return NULL_TREE;
4527 /* Return nonzero if VALUE is a valid constant-valued expression
4528 for use in initializing a static variable; one that can be an
4529 element of a "constant" initializer.
4531 Return null_pointer_node if the value is absolute;
4532 if it is relocatable, return the variable that determines the relocation.
4533 We assume that VALUE has been folded as much as possible;
4534 therefore, we do not need to check for such things as
4535 arithmetic-combinations of integers. */
4536 tree
4537 initializer_constant_valid_p (tree value, tree endtype)
4539 return initializer_constant_valid_p_1 (value, endtype, NULL);
4542 /* Return true if VALUE is a valid constant-valued expression
4543 for use in initializing a static bit-field; one that can be
4544 an element of a "constant" initializer. */
4546 bool
4547 initializer_constant_valid_for_bitfield_p (tree value)
4549 /* For bitfields we support integer constants or possibly nested aggregates
4550 of such. */
4551 switch (TREE_CODE (value))
4553 case CONSTRUCTOR:
4555 unsigned HOST_WIDE_INT idx;
4556 tree elt;
4558 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4559 if (!initializer_constant_valid_for_bitfield_p (elt))
4560 return false;
4561 return true;
4564 case INTEGER_CST:
4565 case REAL_CST:
4566 return true;
4568 case VIEW_CONVERT_EXPR:
4569 case NON_LVALUE_EXPR:
4570 return
4571 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4573 default:
4574 break;
4577 return false;
4580 /* output_constructor outer state of relevance in recursive calls, typically
4581 for nested aggregate bitfields. */
4583 typedef struct {
4584 unsigned int bit_offset; /* current position in ... */
4585 int byte; /* ... the outer byte buffer. */
4586 } oc_outer_state;
4588 static unsigned HOST_WIDE_INT
4589 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int,
4590 oc_outer_state *);
4592 /* Output assembler code for constant EXP, with no label.
4593 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4594 Assumes output_addressed_constants has been done on EXP already.
4596 Generate at least SIZE bytes of assembler data, padding at the end
4597 with zeros if necessary. SIZE must always be specified. The returned
4598 value is the actual number of bytes of assembler data generated, which
4599 may be bigger than SIZE if the object contains a variable length field.
4601 SIZE is important for structure constructors,
4602 since trailing members may have been omitted from the constructor.
4603 It is also important for initialization of arrays from string constants
4604 since the full length of the string constant might not be wanted.
4605 It is also needed for initialization of unions, where the initializer's
4606 type is just one member, and that may not be as long as the union.
4608 There a case in which we would fail to output exactly SIZE bytes:
4609 for a structure constructor that wants to produce more than SIZE bytes.
4610 But such constructors will never be generated for any possible input.
4612 ALIGN is the alignment of the data in bits. */
4614 static unsigned HOST_WIDE_INT
4615 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align)
4617 enum tree_code code;
4618 unsigned HOST_WIDE_INT thissize;
4620 if (size == 0 || flag_syntax_only)
4621 return size;
4623 /* See if we're trying to initialize a pointer in a non-default mode
4624 to the address of some declaration somewhere. If the target says
4625 the mode is valid for pointers, assume the target has a way of
4626 resolving it. */
4627 if (TREE_CODE (exp) == NOP_EXPR
4628 && POINTER_TYPE_P (TREE_TYPE (exp))
4629 && targetm.addr_space.valid_pointer_mode
4630 (TYPE_MODE (TREE_TYPE (exp)),
4631 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4633 tree saved_type = TREE_TYPE (exp);
4635 /* Peel off any intermediate conversions-to-pointer for valid
4636 pointer modes. */
4637 while (TREE_CODE (exp) == NOP_EXPR
4638 && POINTER_TYPE_P (TREE_TYPE (exp))
4639 && targetm.addr_space.valid_pointer_mode
4640 (TYPE_MODE (TREE_TYPE (exp)),
4641 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4642 exp = TREE_OPERAND (exp, 0);
4644 /* If what we're left with is the address of something, we can
4645 convert the address to the final type and output it that
4646 way. */
4647 if (TREE_CODE (exp) == ADDR_EXPR)
4648 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4649 /* Likewise for constant ints. */
4650 else if (TREE_CODE (exp) == INTEGER_CST)
4651 exp = wide_int_to_tree (saved_type, exp);
4655 /* Eliminate any conversions since we'll be outputting the underlying
4656 constant. */
4657 while (CONVERT_EXPR_P (exp)
4658 || TREE_CODE (exp) == NON_LVALUE_EXPR
4659 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4661 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4662 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4664 /* Make sure eliminating the conversion is really a no-op, except with
4665 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4666 union types to allow for Ada unchecked unions. */
4667 if (type_size > op_size
4668 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4669 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4670 /* Keep the conversion. */
4671 break;
4672 else
4673 exp = TREE_OPERAND (exp, 0);
4676 code = TREE_CODE (TREE_TYPE (exp));
4677 thissize = int_size_in_bytes (TREE_TYPE (exp));
4679 /* Allow a constructor with no elements for any data type.
4680 This means to fill the space with zeros. */
4681 if (TREE_CODE (exp) == CONSTRUCTOR
4682 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4684 assemble_zeros (size);
4685 return size;
4688 if (TREE_CODE (exp) == FDESC_EXPR)
4690 #ifdef ASM_OUTPUT_FDESC
4691 HOST_WIDE_INT part = tree_to_shwi (TREE_OPERAND (exp, 1));
4692 tree decl = TREE_OPERAND (exp, 0);
4693 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4694 #else
4695 gcc_unreachable ();
4696 #endif
4697 return size;
4700 /* Now output the underlying data. If we've handling the padding, return.
4701 Otherwise, break and ensure SIZE is the size written. */
4702 switch (code)
4704 case BOOLEAN_TYPE:
4705 case INTEGER_TYPE:
4706 case ENUMERAL_TYPE:
4707 case POINTER_TYPE:
4708 case REFERENCE_TYPE:
4709 case OFFSET_TYPE:
4710 case FIXED_POINT_TYPE:
4711 case NULLPTR_TYPE:
4712 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
4713 EXPAND_INITIALIZER),
4714 MIN (size, thissize), align, 0))
4715 error ("initializer for integer/fixed-point value is too complicated");
4716 break;
4718 case REAL_TYPE:
4719 if (TREE_CODE (exp) != REAL_CST)
4720 error ("initializer for floating value is not a floating constant");
4721 else
4722 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)), align);
4723 break;
4725 case COMPLEX_TYPE:
4726 output_constant (TREE_REALPART (exp), thissize / 2, align);
4727 output_constant (TREE_IMAGPART (exp), thissize / 2,
4728 min_align (align, BITS_PER_UNIT * (thissize / 2)));
4729 break;
4731 case ARRAY_TYPE:
4732 case VECTOR_TYPE:
4733 switch (TREE_CODE (exp))
4735 case CONSTRUCTOR:
4736 return output_constructor (exp, size, align, NULL);
4737 case STRING_CST:
4738 thissize
4739 = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4740 assemble_string (TREE_STRING_POINTER (exp), thissize);
4741 break;
4742 case VECTOR_CST:
4744 enum machine_mode inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4745 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4746 int elt_size = GET_MODE_SIZE (inner);
4747 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align);
4748 thissize = elt_size;
4749 for (unsigned int i = 1; i < VECTOR_CST_NELTS (exp); i++)
4751 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign);
4752 thissize += elt_size;
4754 break;
4756 default:
4757 gcc_unreachable ();
4759 break;
4761 case RECORD_TYPE:
4762 case UNION_TYPE:
4763 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4764 return output_constructor (exp, size, align, NULL);
4766 case ERROR_MARK:
4767 return 0;
4769 default:
4770 gcc_unreachable ();
4773 if (size > thissize)
4774 assemble_zeros (size - thissize);
4776 return size;
4780 /* Subroutine of output_constructor, used for computing the size of
4781 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4782 type with an unspecified upper bound. */
4784 static unsigned HOST_WIDE_INT
4785 array_size_for_constructor (tree val)
4787 tree max_index;
4788 unsigned HOST_WIDE_INT cnt;
4789 tree index, value, tmp;
4790 offset_int i;
4792 /* This code used to attempt to handle string constants that are not
4793 arrays of single-bytes, but nothing else does, so there's no point in
4794 doing it here. */
4795 if (TREE_CODE (val) == STRING_CST)
4796 return TREE_STRING_LENGTH (val);
4798 max_index = NULL_TREE;
4799 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
4801 if (TREE_CODE (index) == RANGE_EXPR)
4802 index = TREE_OPERAND (index, 1);
4803 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
4804 max_index = index;
4807 if (max_index == NULL_TREE)
4808 return 0;
4810 /* Compute the total number of array elements. */
4811 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
4812 i = wi::to_offset (max_index) - wi::to_offset (tmp) + 1;
4814 /* Multiply by the array element unit size to find number of bytes. */
4815 i *= wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
4817 gcc_assert (wi::fits_uhwi_p (i));
4818 return i.to_uhwi ();
4821 /* Other datastructures + helpers for output_constructor. */
4823 /* output_constructor local state to support interaction with helpers. */
4825 typedef struct {
4827 /* Received arguments. */
4828 tree exp; /* Constructor expression. */
4829 tree type; /* Type of constructor expression. */
4830 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */
4831 unsigned int align; /* Known initial alignment. */
4832 tree min_index; /* Lower bound if specified for an array. */
4834 /* Output processing state. */
4835 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */
4836 int byte; /* Part of a bitfield byte yet to be output. */
4837 int last_relative_index; /* Implicit or explicit index of the last
4838 array element output within a bitfield. */
4839 bool byte_buffer_in_use; /* Whether BYTE is in use. */
4841 /* Current element. */
4842 tree field; /* Current field decl in a record. */
4843 tree val; /* Current element value. */
4844 tree index; /* Current element index. */
4846 } oc_local_state;
4848 /* Helper for output_constructor. From the current LOCAL state, output a
4849 RANGE_EXPR element. */
4851 static void
4852 output_constructor_array_range (oc_local_state *local)
4854 unsigned HOST_WIDE_INT fieldsize
4855 = int_size_in_bytes (TREE_TYPE (local->type));
4857 HOST_WIDE_INT lo_index
4858 = tree_to_shwi (TREE_OPERAND (local->index, 0));
4859 HOST_WIDE_INT hi_index
4860 = tree_to_shwi (TREE_OPERAND (local->index, 1));
4861 HOST_WIDE_INT index;
4863 unsigned int align2
4864 = min_align (local->align, fieldsize * BITS_PER_UNIT);
4866 for (index = lo_index; index <= hi_index; index++)
4868 /* Output the element's initial value. */
4869 if (local->val == NULL_TREE)
4870 assemble_zeros (fieldsize);
4871 else
4872 fieldsize = output_constant (local->val, fieldsize, align2);
4874 /* Count its size. */
4875 local->total_bytes += fieldsize;
4879 /* Helper for output_constructor. From the current LOCAL state, output a
4880 field element that is not true bitfield or part of an outer one. */
4882 static void
4883 output_constructor_regular_field (oc_local_state *local)
4885 /* Field size and position. Since this structure is static, we know the
4886 positions are constant. */
4887 unsigned HOST_WIDE_INT fieldsize;
4888 HOST_WIDE_INT fieldpos;
4890 unsigned int align2;
4892 if (local->index != NULL_TREE)
4894 /* Perform the index calculation in modulo arithmetic but
4895 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
4896 but we are using an unsigned sizetype. */
4897 unsigned prec = TYPE_PRECISION (sizetype);
4898 offset_int idx = wi::sext (wi::to_offset (local->index)
4899 - wi::to_offset (local->min_index), prec);
4900 fieldpos = (idx * wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (local->val))))
4901 .to_short_addr ();
4903 else if (local->field != NULL_TREE)
4904 fieldpos = int_byte_position (local->field);
4905 else
4906 fieldpos = 0;
4908 /* Output any buffered-up bit-fields preceding this element. */
4909 if (local->byte_buffer_in_use)
4911 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4912 local->total_bytes++;
4913 local->byte_buffer_in_use = false;
4916 /* Advance to offset of this element.
4917 Note no alignment needed in an array, since that is guaranteed
4918 if each element has the proper size. */
4919 if ((local->field != NULL_TREE || local->index != NULL_TREE)
4920 && fieldpos > local->total_bytes)
4922 assemble_zeros (fieldpos - local->total_bytes);
4923 local->total_bytes = fieldpos;
4926 /* Find the alignment of this element. */
4927 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
4929 /* Determine size this element should occupy. */
4930 if (local->field)
4932 fieldsize = 0;
4934 /* If this is an array with an unspecified upper bound,
4935 the initializer determines the size. */
4936 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
4937 but we cannot do this until the deprecated support for
4938 initializing zero-length array members is removed. */
4939 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
4940 && TYPE_DOMAIN (TREE_TYPE (local->field))
4941 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field))))
4943 fieldsize = array_size_for_constructor (local->val);
4944 /* Given a non-empty initialization, this field had
4945 better be last. */
4946 gcc_assert (!fieldsize || !DECL_CHAIN (local->field));
4948 else
4949 fieldsize = tree_to_uhwi (DECL_SIZE_UNIT (local->field));
4951 else
4952 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
4954 /* Output the element's initial value. */
4955 if (local->val == NULL_TREE)
4956 assemble_zeros (fieldsize);
4957 else
4958 fieldsize = output_constant (local->val, fieldsize, align2);
4960 /* Count its size. */
4961 local->total_bytes += fieldsize;
4964 /* Helper for output_constructor. From the LOCAL state, output an element
4965 that is a true bitfield or part of an outer one. BIT_OFFSET is the offset
4966 from the start of a possibly ongoing outer byte buffer. */
4968 static void
4969 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
4971 /* Bit size of this element. */
4972 HOST_WIDE_INT ebitsize
4973 = (local->field
4974 ? tree_to_uhwi (DECL_SIZE (local->field))
4975 : tree_to_uhwi (TYPE_SIZE (TREE_TYPE (local->type))));
4977 /* Relative index of this element if this is an array component. */
4978 HOST_WIDE_INT relative_index
4979 = (!local->field
4980 ? (local->index
4981 ? (tree_to_shwi (local->index)
4982 - tree_to_shwi (local->min_index))
4983 : local->last_relative_index + 1)
4984 : 0);
4986 /* Bit position of this element from the start of the containing
4987 constructor. */
4988 HOST_WIDE_INT constructor_relative_ebitpos
4989 = (local->field
4990 ? int_bit_position (local->field)
4991 : ebitsize * relative_index);
4993 /* Bit position of this element from the start of a possibly ongoing
4994 outer byte buffer. */
4995 HOST_WIDE_INT byte_relative_ebitpos
4996 = bit_offset + constructor_relative_ebitpos;
4998 /* From the start of a possibly ongoing outer byte buffer, offsets to
4999 the first bit of this element and to the first bit past the end of
5000 this element. */
5001 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
5002 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
5004 local->last_relative_index = relative_index;
5006 if (local->val == NULL_TREE)
5007 local->val = integer_zero_node;
5009 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
5010 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
5011 local->val = TREE_OPERAND (local->val, 0);
5013 if (TREE_CODE (local->val) != INTEGER_CST
5014 && TREE_CODE (local->val) != CONSTRUCTOR)
5016 error ("invalid initial value for member %qE", DECL_NAME (local->field));
5017 return;
5020 /* If this field does not start in this (or next) byte, skip some bytes. */
5021 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5023 /* Output remnant of any bit field in previous bytes. */
5024 if (local->byte_buffer_in_use)
5026 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5027 local->total_bytes++;
5028 local->byte_buffer_in_use = false;
5031 /* If still not at proper byte, advance to there. */
5032 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5034 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
5035 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
5036 local->total_bytes = next_offset / BITS_PER_UNIT;
5040 /* Set up the buffer if necessary. */
5041 if (!local->byte_buffer_in_use)
5043 local->byte = 0;
5044 if (ebitsize > 0)
5045 local->byte_buffer_in_use = true;
5048 /* If this is nested constructor, recurse passing the bit offset and the
5049 pending data, then retrieve the new pending data afterwards. */
5050 if (TREE_CODE (local->val) == CONSTRUCTOR)
5052 oc_outer_state temp_state;
5053 temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5054 temp_state.byte = local->byte;
5055 local->total_bytes
5056 += output_constructor (local->val, 0, 0, &temp_state);
5057 local->byte = temp_state.byte;
5058 return;
5061 /* Otherwise, we must split the element into pieces that fall within
5062 separate bytes, and combine each byte with previous or following
5063 bit-fields. */
5064 while (next_offset < end_offset)
5066 int this_time;
5067 int shift;
5068 HOST_WIDE_INT value;
5069 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5070 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5072 /* Advance from byte to byte within this element when necessary. */
5073 while (next_byte != local->total_bytes)
5075 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5076 local->total_bytes++;
5077 local->byte = 0;
5080 /* Number of bits we can process at once (all part of the same byte). */
5081 this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5082 if (BYTES_BIG_ENDIAN)
5084 /* On big-endian machine, take the most significant bits
5085 first (of the bits that are significant)
5086 and put them into bytes from the most significant end. */
5087 shift = end_offset - next_offset - this_time;
5089 /* Don't try to take a bunch of bits that cross
5090 the word boundary in the INTEGER_CST. We can
5091 only select bits from the LOW or HIGH part
5092 not from both. */
5093 if ((shift / HOST_BITS_PER_WIDE_INT)
5094 != ((shift + this_time) / HOST_BITS_PER_WIDE_INT))
5095 this_time = (shift + this_time) & (HOST_BITS_PER_WIDE_INT - 1);
5097 /* Now get the bits from the appropriate constant word. */
5098 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5099 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5101 /* Get the result. This works only when:
5102 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5103 local->byte |= (((value >> shift)
5104 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5105 << (BITS_PER_UNIT - this_time - next_bit));
5107 else
5109 /* On little-endian machines,
5110 take first the least significant bits of the value
5111 and pack them starting at the least significant
5112 bits of the bytes. */
5113 shift = next_offset - byte_relative_ebitpos;
5115 /* Don't try to take a bunch of bits that cross
5116 the word boundary in the INTEGER_CST. We can
5117 only select bits from the LOW or HIGH part
5118 not from both. */
5119 if ((shift / HOST_BITS_PER_WIDE_INT)
5120 != ((shift + this_time) / HOST_BITS_PER_WIDE_INT))
5121 this_time = (HOST_BITS_PER_WIDE_INT - shift);
5123 /* Now get the bits from the appropriate constant word. */
5124 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5125 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5127 /* Get the result. This works only when:
5128 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5129 local->byte |= (((value >> shift)
5130 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5131 << next_bit);
5134 next_offset += this_time;
5135 local->byte_buffer_in_use = true;
5139 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5140 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5141 caller output state of relevance in recursive invocations. */
5143 static unsigned HOST_WIDE_INT
5144 output_constructor (tree exp, unsigned HOST_WIDE_INT size,
5145 unsigned int align, oc_outer_state *outer)
5147 unsigned HOST_WIDE_INT cnt;
5148 constructor_elt *ce;
5150 oc_local_state local;
5152 /* Setup our local state to communicate with helpers. */
5153 local.exp = exp;
5154 local.type = TREE_TYPE (exp);
5155 local.size = size;
5156 local.align = align;
5157 if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5158 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5159 else
5160 local.min_index = NULL_TREE;
5162 local.total_bytes = 0;
5163 local.byte_buffer_in_use = outer != NULL;
5164 local.byte = outer ? outer->byte : 0;
5165 local.last_relative_index = -1;
5167 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5169 /* As CE goes through the elements of the constant, FIELD goes through the
5170 structure fields if the constant is a structure. If the constant is a
5171 union, we override this by getting the field from the TREE_LIST element.
5172 But the constant could also be an array. Then FIELD is zero.
5174 There is always a maximum of one element in the chain LINK for unions
5175 (even if the initializer in a source program incorrectly contains
5176 more one). */
5178 if (TREE_CODE (local.type) == RECORD_TYPE)
5179 local.field = TYPE_FIELDS (local.type);
5180 else
5181 local.field = NULL_TREE;
5183 for (cnt = 0;
5184 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5185 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5187 local.val = ce->value;
5188 local.index = NULL_TREE;
5190 /* The element in a union constructor specifies the proper field
5191 or index. */
5192 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5193 local.field = ce->index;
5195 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5196 local.index = ce->index;
5198 if (local.field && flag_verbose_asm)
5199 fprintf (asm_out_file, "%s %s:\n",
5200 ASM_COMMENT_START,
5201 DECL_NAME (local.field)
5202 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5203 : "<anonymous>");
5205 /* Eliminate the marker that makes a cast not be an lvalue. */
5206 if (local.val != NULL_TREE)
5207 STRIP_NOPS (local.val);
5209 /* Output the current element, using the appropriate helper ... */
5211 /* For an array slice not part of an outer bitfield. */
5212 if (!outer
5213 && local.index != NULL_TREE
5214 && TREE_CODE (local.index) == RANGE_EXPR)
5215 output_constructor_array_range (&local);
5217 /* For a field that is neither a true bitfield nor part of an outer one,
5218 known to be at least byte aligned and multiple-of-bytes long. */
5219 else if (!outer
5220 && (local.field == NULL_TREE
5221 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5222 output_constructor_regular_field (&local);
5224 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5225 supported for scalar fields, so we may need to convert first. */
5226 else
5228 if (TREE_CODE (local.val) == REAL_CST)
5229 local.val
5230 = fold_unary (VIEW_CONVERT_EXPR,
5231 build_nonstandard_integer_type
5232 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5233 local.val);
5234 output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5238 /* If we are not at toplevel, save the pending data for our caller.
5239 Otherwise output the pending data and padding zeros as needed. */
5240 if (outer)
5241 outer->byte = local.byte;
5242 else
5244 if (local.byte_buffer_in_use)
5246 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5247 local.total_bytes++;
5250 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5252 assemble_zeros (local.size - local.total_bytes);
5253 local.total_bytes = local.size;
5257 return local.total_bytes;
5260 /* Mark DECL as weak. */
5262 static void
5263 mark_weak (tree decl)
5265 DECL_WEAK (decl) = 1;
5267 if (DECL_RTL_SET_P (decl)
5268 && MEM_P (DECL_RTL (decl))
5269 && XEXP (DECL_RTL (decl), 0)
5270 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5271 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5274 /* Merge weak status between NEWDECL and OLDDECL. */
5276 void
5277 merge_weak (tree newdecl, tree olddecl)
5279 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5281 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5283 tree *pwd;
5284 /* We put the NEWDECL on the weak_decls list at some point
5285 and OLDDECL as well. Keep just OLDDECL on the list. */
5286 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5287 if (TREE_VALUE (*pwd) == newdecl)
5289 *pwd = TREE_CHAIN (*pwd);
5290 break;
5293 return;
5296 if (DECL_WEAK (newdecl))
5298 tree wd;
5300 /* NEWDECL is weak, but OLDDECL is not. */
5302 /* If we already output the OLDDECL, we're in trouble; we can't
5303 go back and make it weak. This should never happen in
5304 unit-at-a-time compilation. */
5305 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5307 /* If we've already generated rtl referencing OLDDECL, we may
5308 have done so in a way that will not function properly with
5309 a weak symbol. Again in unit-at-a-time this should be
5310 impossible. */
5311 gcc_assert (!TREE_USED (olddecl)
5312 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5314 if (TARGET_SUPPORTS_WEAK)
5316 /* We put the NEWDECL on the weak_decls list at some point.
5317 Replace it with the OLDDECL. */
5318 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5319 if (TREE_VALUE (wd) == newdecl)
5321 TREE_VALUE (wd) = olddecl;
5322 break;
5324 /* We may not find the entry on the list. If NEWDECL is a
5325 weak alias, then we will have already called
5326 globalize_decl to remove the entry; in that case, we do
5327 not need to do anything. */
5330 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5331 mark_weak (olddecl);
5333 else
5334 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5335 weak. Just update NEWDECL to indicate that it's weak too. */
5336 mark_weak (newdecl);
5339 /* Declare DECL to be a weak symbol. */
5341 void
5342 declare_weak (tree decl)
5344 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5345 if (! TREE_PUBLIC (decl))
5346 error ("weak declaration of %q+D must be public", decl);
5347 else if (!TARGET_SUPPORTS_WEAK)
5348 warning (0, "weak declaration of %q+D not supported", decl);
5350 mark_weak (decl);
5351 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5352 DECL_ATTRIBUTES (decl)
5353 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5356 static void
5357 weak_finish_1 (tree decl)
5359 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5360 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5361 #endif
5363 if (! TREE_USED (decl))
5364 return;
5366 #ifdef ASM_WEAKEN_DECL
5367 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5368 #else
5369 #ifdef ASM_WEAKEN_LABEL
5370 ASM_WEAKEN_LABEL (asm_out_file, name);
5371 #else
5372 #ifdef ASM_OUTPUT_WEAK_ALIAS
5374 static bool warn_once = 0;
5375 if (! warn_once)
5377 warning (0, "only weak aliases are supported in this configuration");
5378 warn_once = 1;
5380 return;
5382 #endif
5383 #endif
5384 #endif
5387 /* Fiven an assembly name, find the decl it is associated with. */
5388 static tree
5389 find_decl (tree target)
5391 symtab_node *node = symtab_node_for_asm (target);
5392 if (node)
5393 return node->decl;
5394 return NULL_TREE;
5397 /* This TREE_LIST contains weakref targets. */
5399 static GTY(()) tree weakref_targets;
5401 /* Emit any pending weak declarations. */
5403 void
5404 weak_finish (void)
5406 tree t;
5408 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5410 tree alias_decl = TREE_PURPOSE (t);
5411 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5413 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5414 /* Remove alias_decl from the weak list, but leave entries for
5415 the target alone. */
5416 target = NULL_TREE;
5417 #ifndef ASM_OUTPUT_WEAKREF
5418 else if (! TREE_SYMBOL_REFERENCED (target))
5420 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5421 defined, otherwise we and weak_finish_1 would use
5422 different macros. */
5423 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5424 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5425 # else
5426 tree decl = find_decl (target);
5428 if (! decl)
5430 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5431 TREE_CODE (alias_decl), target,
5432 TREE_TYPE (alias_decl));
5434 DECL_EXTERNAL (decl) = 1;
5435 TREE_PUBLIC (decl) = 1;
5436 DECL_ARTIFICIAL (decl) = 1;
5437 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5438 TREE_USED (decl) = 1;
5441 weak_finish_1 (decl);
5442 # endif
5444 #endif
5447 tree *p;
5448 tree t2;
5450 /* Remove the alias and the target from the pending weak list
5451 so that we do not emit any .weak directives for the former,
5452 nor multiple .weak directives for the latter. */
5453 for (p = &weak_decls; (t2 = *p) ; )
5455 if (TREE_VALUE (t2) == alias_decl
5456 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5457 *p = TREE_CHAIN (t2);
5458 else
5459 p = &TREE_CHAIN (t2);
5462 /* Remove other weakrefs to the same target, to speed things up. */
5463 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5465 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5466 *p = TREE_CHAIN (t2);
5467 else
5468 p = &TREE_CHAIN (t2);
5473 for (t = weak_decls; t; t = TREE_CHAIN (t))
5475 tree decl = TREE_VALUE (t);
5477 weak_finish_1 (decl);
5481 /* Emit the assembly bits to indicate that DECL is globally visible. */
5483 static void
5484 globalize_decl (tree decl)
5487 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5488 if (DECL_WEAK (decl))
5490 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5491 tree *p, t;
5493 #ifdef ASM_WEAKEN_DECL
5494 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5495 #else
5496 ASM_WEAKEN_LABEL (asm_out_file, name);
5497 #endif
5499 /* Remove this function from the pending weak list so that
5500 we do not emit multiple .weak directives for it. */
5501 for (p = &weak_decls; (t = *p) ; )
5503 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5504 *p = TREE_CHAIN (t);
5505 else
5506 p = &TREE_CHAIN (t);
5509 /* Remove weakrefs to the same target from the pending weakref
5510 list, for the same reason. */
5511 for (p = &weakref_targets; (t = *p) ; )
5513 if (DECL_ASSEMBLER_NAME (decl)
5514 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5515 *p = TREE_CHAIN (t);
5516 else
5517 p = &TREE_CHAIN (t);
5520 return;
5522 #endif
5524 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5527 vec<alias_pair, va_gc> *alias_pairs;
5529 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5530 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5531 tree node is DECL to have the value of the tree node TARGET. */
5533 void
5534 do_assemble_alias (tree decl, tree target)
5536 /* Emulated TLS had better not get this var. */
5537 gcc_assert (!(!targetm.have_tls
5538 && TREE_CODE (decl) == VAR_DECL
5539 && DECL_THREAD_LOCAL_P (decl)));
5541 if (TREE_ASM_WRITTEN (decl))
5542 return;
5544 /* We must force creation of DECL_RTL for debug info generation, even though
5545 we don't use it here. */
5546 make_decl_rtl (decl);
5548 TREE_ASM_WRITTEN (decl) = 1;
5549 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5551 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5553 ultimate_transparent_alias_target (&target);
5555 if (!TREE_SYMBOL_REFERENCED (target))
5556 weakref_targets = tree_cons (decl, target, weakref_targets);
5558 #ifdef ASM_OUTPUT_WEAKREF
5559 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5560 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5561 IDENTIFIER_POINTER (target));
5562 #else
5563 if (!TARGET_SUPPORTS_WEAK)
5565 error_at (DECL_SOURCE_LOCATION (decl),
5566 "weakref is not supported in this configuration");
5567 return;
5569 #endif
5570 return;
5573 #ifdef ASM_OUTPUT_DEF
5574 /* Make name accessible from other files, if appropriate. */
5576 if (TREE_PUBLIC (decl))
5578 globalize_decl (decl);
5579 maybe_assemble_visibility (decl);
5581 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5583 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5584 if (targetm.has_ifunc_p ())
5585 ASM_OUTPUT_TYPE_DIRECTIVE
5586 (asm_out_file, IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5587 IFUNC_ASM_TYPE);
5588 else
5589 #endif
5590 error_at (DECL_SOURCE_LOCATION (decl),
5591 "ifunc is not supported on this target");
5594 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5595 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5596 # else
5597 ASM_OUTPUT_DEF (asm_out_file,
5598 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5599 IDENTIFIER_POINTER (target));
5600 # endif
5601 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5603 const char *name;
5604 tree *p, t;
5606 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5607 # ifdef ASM_WEAKEN_DECL
5608 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5609 # else
5610 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5611 # endif
5612 /* Remove this function from the pending weak list so that
5613 we do not emit multiple .weak directives for it. */
5614 for (p = &weak_decls; (t = *p) ; )
5615 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5616 *p = TREE_CHAIN (t);
5617 else
5618 p = &TREE_CHAIN (t);
5620 /* Remove weakrefs to the same target from the pending weakref
5621 list, for the same reason. */
5622 for (p = &weakref_targets; (t = *p) ; )
5624 if (DECL_ASSEMBLER_NAME (decl)
5625 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5626 *p = TREE_CHAIN (t);
5627 else
5628 p = &TREE_CHAIN (t);
5631 #endif
5634 /* Emit an assembler directive to make the symbol for DECL an alias to
5635 the symbol for TARGET. */
5637 void
5638 assemble_alias (tree decl, tree target)
5640 tree target_decl;
5642 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5644 tree alias = DECL_ASSEMBLER_NAME (decl);
5646 ultimate_transparent_alias_target (&target);
5648 if (alias == target)
5649 error ("weakref %q+D ultimately targets itself", decl);
5650 if (TREE_PUBLIC (decl))
5651 error ("weakref %q+D must have static linkage", decl);
5653 else
5655 #if !defined (ASM_OUTPUT_DEF)
5656 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5657 error_at (DECL_SOURCE_LOCATION (decl),
5658 "alias definitions not supported in this configuration");
5659 TREE_ASM_WRITTEN (decl) = 1;
5660 return;
5661 # else
5662 if (!DECL_WEAK (decl))
5664 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5665 error_at (DECL_SOURCE_LOCATION (decl),
5666 "ifunc is not supported in this configuration");
5667 else
5668 error_at (DECL_SOURCE_LOCATION (decl),
5669 "only weak aliases are supported in this configuration");
5670 TREE_ASM_WRITTEN (decl) = 1;
5671 return;
5673 # endif
5674 #endif
5676 TREE_USED (decl) = 1;
5678 /* Allow aliases to aliases. */
5679 if (TREE_CODE (decl) == FUNCTION_DECL)
5680 cgraph_get_create_node (decl)->alias = true;
5681 else
5682 varpool_node_for_decl (decl)->alias = true;
5684 /* If the target has already been emitted, we don't have to queue the
5685 alias. This saves a tad of memory. */
5686 if (cgraph_global_info_ready)
5687 target_decl = find_decl (target);
5688 else
5689 target_decl= NULL;
5690 if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5691 || cgraph_state >= CGRAPH_STATE_EXPANSION)
5692 do_assemble_alias (decl, target);
5693 else
5695 alias_pair p = {decl, target};
5696 vec_safe_push (alias_pairs, p);
5700 /* Record and output a table of translations from original function
5701 to its transaction aware clone. Note that tm_pure functions are
5702 considered to be their own clone. */
5704 static GTY((if_marked ("tree_map_marked_p"), param_is (struct tree_map)))
5705 htab_t tm_clone_hash;
5707 void
5708 record_tm_clone_pair (tree o, tree n)
5710 struct tree_map **slot, *h;
5712 if (tm_clone_hash == NULL)
5713 tm_clone_hash = htab_create_ggc (32, tree_map_hash, tree_map_eq, 0);
5715 h = ggc_alloc<tree_map> ();
5716 h->hash = htab_hash_pointer (o);
5717 h->base.from = o;
5718 h->to = n;
5720 slot = (struct tree_map **)
5721 htab_find_slot_with_hash (tm_clone_hash, h, h->hash, INSERT);
5722 *slot = h;
5725 tree
5726 get_tm_clone_pair (tree o)
5728 if (tm_clone_hash)
5730 struct tree_map *h, in;
5732 in.base.from = o;
5733 in.hash = htab_hash_pointer (o);
5734 h = (struct tree_map *) htab_find_with_hash (tm_clone_hash,
5735 &in, in.hash);
5736 if (h)
5737 return h->to;
5739 return NULL_TREE;
5742 typedef struct tm_alias_pair
5744 unsigned int uid;
5745 tree from;
5746 tree to;
5747 } tm_alias_pair;
5750 /* Helper function for finish_tm_clone_pairs. Dump a hash table entry
5751 into a VEC in INFO. */
5753 static int
5754 dump_tm_clone_to_vec (void **slot, void *info)
5756 struct tree_map *map = (struct tree_map *) *slot;
5757 vec<tm_alias_pair> *tm_alias_pairs = (vec<tm_alias_pair> *) info;
5758 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
5759 tm_alias_pairs->safe_push (p);
5760 return 1;
5763 /* Dump the actual pairs to the .tm_clone_table section. */
5765 static void
5766 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
5768 unsigned i;
5769 tm_alias_pair *p;
5770 bool switched = false;
5772 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
5774 tree src = p->from;
5775 tree dst = p->to;
5776 struct cgraph_node *src_n = cgraph_get_node (src);
5777 struct cgraph_node *dst_n = cgraph_get_node (dst);
5779 /* The function ipa_tm_create_version() marks the clone as needed if
5780 the original function was needed. But we also mark the clone as
5781 needed if we ever called the clone indirectly through
5782 TM_GETTMCLONE. If neither of these are true, we didn't generate
5783 a clone, and we didn't call it indirectly... no sense keeping it
5784 in the clone table. */
5785 if (!dst_n || !dst_n->definition)
5786 continue;
5788 /* This covers the case where we have optimized the original
5789 function away, and only access the transactional clone. */
5790 if (!src_n || !src_n->definition)
5791 continue;
5793 if (!switched)
5795 switch_to_section (targetm.asm_out.tm_clone_table_section ());
5796 assemble_align (POINTER_SIZE);
5797 switched = true;
5800 assemble_integer (XEXP (DECL_RTL (src), 0),
5801 POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
5802 assemble_integer (XEXP (DECL_RTL (dst), 0),
5803 POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
5807 /* Provide a default for the tm_clone_table section. */
5809 section *
5810 default_clone_table_section (void)
5812 return get_named_section (NULL, ".tm_clone_table", 3);
5815 /* Helper comparison function for qsorting by the DECL_UID stored in
5816 alias_pair->emitted_diags. */
5818 static int
5819 tm_alias_pair_cmp (const void *x, const void *y)
5821 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
5822 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
5823 if (p1->uid < p2->uid)
5824 return -1;
5825 if (p1->uid > p2->uid)
5826 return 1;
5827 return 0;
5830 void
5831 finish_tm_clone_pairs (void)
5833 vec<tm_alias_pair> tm_alias_pairs = vNULL;
5835 if (tm_clone_hash == NULL)
5836 return;
5838 /* We need a determenistic order for the .tm_clone_table, otherwise
5839 we will get bootstrap comparison failures, so dump the hash table
5840 to a vector, sort it, and dump the vector. */
5842 /* Dump the hashtable to a vector. */
5843 htab_traverse_noresize (tm_clone_hash, dump_tm_clone_to_vec,
5844 (void *) &tm_alias_pairs);
5845 /* Sort it. */
5846 tm_alias_pairs.qsort (tm_alias_pair_cmp);
5848 /* Dump it. */
5849 dump_tm_clone_pairs (tm_alias_pairs);
5851 htab_delete (tm_clone_hash);
5852 tm_clone_hash = NULL;
5853 tm_alias_pairs.release ();
5857 /* Emit an assembler directive to set symbol for DECL visibility to
5858 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
5860 void
5861 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
5862 int vis ATTRIBUTE_UNUSED)
5864 #ifdef HAVE_GAS_HIDDEN
5865 static const char * const visibility_types[] = {
5866 NULL, "protected", "hidden", "internal"
5869 const char *name, *type;
5871 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5872 type = visibility_types[vis];
5874 fprintf (asm_out_file, "\t.%s\t", type);
5875 assemble_name (asm_out_file, name);
5876 fprintf (asm_out_file, "\n");
5877 #else
5878 if (!DECL_ARTIFICIAL (decl))
5879 warning (OPT_Wattributes, "visibility attribute not supported "
5880 "in this configuration; ignored");
5881 #endif
5884 /* A helper function to call assemble_visibility when needed for a decl. */
5887 maybe_assemble_visibility (tree decl)
5889 enum symbol_visibility vis = DECL_VISIBILITY (decl);
5891 if (vis != VISIBILITY_DEFAULT)
5893 targetm.asm_out.assemble_visibility (decl, vis);
5894 return 1;
5896 else
5897 return 0;
5900 /* Returns 1 if the target configuration supports defining public symbols
5901 so that one of them will be chosen at link time instead of generating a
5902 multiply-defined symbol error, whether through the use of weak symbols or
5903 a target-specific mechanism for having duplicates discarded. */
5906 supports_one_only (void)
5908 if (SUPPORTS_ONE_ONLY)
5909 return 1;
5910 return TARGET_SUPPORTS_WEAK;
5913 /* Set up DECL as a public symbol that can be defined in multiple
5914 translation units without generating a linker error. */
5916 void
5917 make_decl_one_only (tree decl, tree comdat_group)
5919 gcc_assert (TREE_CODE (decl) == VAR_DECL
5920 || TREE_CODE (decl) == FUNCTION_DECL);
5922 TREE_PUBLIC (decl) = 1;
5924 if (SUPPORTS_ONE_ONLY)
5926 #ifdef MAKE_DECL_ONE_ONLY
5927 MAKE_DECL_ONE_ONLY (decl);
5928 #endif
5929 DECL_COMDAT_GROUP (decl) = comdat_group;
5931 else if (TREE_CODE (decl) == VAR_DECL
5932 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node))
5933 DECL_COMMON (decl) = 1;
5934 else
5936 gcc_assert (TARGET_SUPPORTS_WEAK);
5937 DECL_WEAK (decl) = 1;
5941 void
5942 init_varasm_once (void)
5944 section_htab = htab_create_ggc (31, section_entry_hash,
5945 section_entry_eq, NULL);
5946 object_block_htab = htab_create_ggc (31, object_block_entry_hash,
5947 object_block_entry_eq, NULL);
5948 const_desc_htab = htab_create_ggc (1009, const_desc_hash,
5949 const_desc_eq, NULL);
5951 const_alias_set = new_alias_set ();
5952 shared_constant_pool = create_constant_pool ();
5954 #ifdef TEXT_SECTION_ASM_OP
5955 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
5956 TEXT_SECTION_ASM_OP);
5957 #endif
5959 #ifdef DATA_SECTION_ASM_OP
5960 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5961 DATA_SECTION_ASM_OP);
5962 #endif
5964 #ifdef SDATA_SECTION_ASM_OP
5965 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5966 SDATA_SECTION_ASM_OP);
5967 #endif
5969 #ifdef READONLY_DATA_SECTION_ASM_OP
5970 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
5971 READONLY_DATA_SECTION_ASM_OP);
5972 #endif
5974 #ifdef CTORS_SECTION_ASM_OP
5975 ctors_section = get_unnamed_section (0, output_section_asm_op,
5976 CTORS_SECTION_ASM_OP);
5977 #endif
5979 #ifdef DTORS_SECTION_ASM_OP
5980 dtors_section = get_unnamed_section (0, output_section_asm_op,
5981 DTORS_SECTION_ASM_OP);
5982 #endif
5984 #ifdef BSS_SECTION_ASM_OP
5985 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5986 output_section_asm_op,
5987 BSS_SECTION_ASM_OP);
5988 #endif
5990 #ifdef SBSS_SECTION_ASM_OP
5991 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5992 output_section_asm_op,
5993 SBSS_SECTION_ASM_OP);
5994 #endif
5996 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5997 | SECTION_COMMON, emit_tls_common);
5998 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5999 | SECTION_COMMON, emit_local);
6000 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6001 | SECTION_COMMON, emit_common);
6003 #if defined ASM_OUTPUT_ALIGNED_BSS
6004 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
6005 emit_bss);
6006 #endif
6008 targetm.asm_out.init_sections ();
6010 if (readonly_data_section == NULL)
6011 readonly_data_section = text_section;
6013 #ifdef ASM_OUTPUT_EXTERNAL
6014 pending_assemble_externals_set = pointer_set_create ();
6015 #endif
6018 enum tls_model
6019 decl_default_tls_model (const_tree decl)
6021 enum tls_model kind;
6022 bool is_local;
6024 is_local = targetm.binds_local_p (decl);
6025 if (!flag_shlib)
6027 if (is_local)
6028 kind = TLS_MODEL_LOCAL_EXEC;
6029 else
6030 kind = TLS_MODEL_INITIAL_EXEC;
6033 /* Local dynamic is inefficient when we're not combining the
6034 parts of the address. */
6035 else if (optimize && is_local)
6036 kind = TLS_MODEL_LOCAL_DYNAMIC;
6037 else
6038 kind = TLS_MODEL_GLOBAL_DYNAMIC;
6039 if (kind < flag_tls_default)
6040 kind = flag_tls_default;
6042 return kind;
6045 /* Select a set of attributes for section NAME based on the properties
6046 of DECL and whether or not RELOC indicates that DECL's initializer
6047 might contain runtime relocations.
6049 We make the section read-only and executable for a function decl,
6050 read-only for a const data decl, and writable for a non-const data decl. */
6052 unsigned int
6053 default_section_type_flags (tree decl, const char *name, int reloc)
6055 unsigned int flags;
6057 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6058 flags = SECTION_CODE;
6059 else if (decl)
6061 enum section_category category
6062 = categorize_decl_for_section (decl, reloc);
6063 if (decl_readonly_section_1 (category))
6064 flags = 0;
6065 else if (category == SECCAT_DATA_REL_RO
6066 || category == SECCAT_DATA_REL_RO_LOCAL)
6067 flags = SECTION_WRITE | SECTION_RELRO;
6068 else
6069 flags = SECTION_WRITE;
6071 else
6073 flags = SECTION_WRITE;
6074 if (strcmp (name, ".data.rel.ro") == 0
6075 || strcmp (name, ".data.rel.ro.local") == 0)
6076 flags |= SECTION_RELRO;
6079 if (decl && DECL_P (decl) && DECL_ONE_ONLY (decl))
6080 flags |= SECTION_LINKONCE;
6082 if (strcmp (name, ".vtable_map_vars") == 0)
6083 flags |= SECTION_LINKONCE;
6085 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6086 flags |= SECTION_TLS | SECTION_WRITE;
6088 if (strcmp (name, ".bss") == 0
6089 || strncmp (name, ".bss.", 5) == 0
6090 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6091 || strcmp (name, ".sbss") == 0
6092 || strncmp (name, ".sbss.", 6) == 0
6093 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6094 flags |= SECTION_BSS;
6096 if (strcmp (name, ".tdata") == 0
6097 || strncmp (name, ".tdata.", 7) == 0
6098 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6099 flags |= SECTION_TLS;
6101 if (strcmp (name, ".tbss") == 0
6102 || strncmp (name, ".tbss.", 6) == 0
6103 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6104 flags |= SECTION_TLS | SECTION_BSS;
6106 /* These three sections have special ELF types. They are neither
6107 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
6108 want to print a section type (@progbits or @nobits). If someone
6109 is silly enough to emit code or TLS variables to one of these
6110 sections, then don't handle them specially. */
6111 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6112 && (strcmp (name, ".init_array") == 0
6113 || strcmp (name, ".fini_array") == 0
6114 || strcmp (name, ".preinit_array") == 0))
6115 flags |= SECTION_NOTYPE;
6117 return flags;
6120 /* Return true if the target supports some form of global BSS,
6121 either through bss_noswitch_section, or by selecting a BSS
6122 section in TARGET_ASM_SELECT_SECTION. */
6124 bool
6125 have_global_bss_p (void)
6127 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6130 /* Output assembly to switch to section NAME with attribute FLAGS.
6131 Four variants for common object file formats. */
6133 void
6134 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6135 unsigned int flags ATTRIBUTE_UNUSED,
6136 tree decl ATTRIBUTE_UNUSED)
6138 /* Some object formats don't support named sections at all. The
6139 front-end should already have flagged this as an error. */
6140 gcc_unreachable ();
6143 #ifndef TLS_SECTION_ASM_FLAG
6144 #define TLS_SECTION_ASM_FLAG 'T'
6145 #endif
6147 void
6148 default_elf_asm_named_section (const char *name, unsigned int flags,
6149 tree decl ATTRIBUTE_UNUSED)
6151 char flagchars[10], *f = flagchars;
6153 /* If we have already declared this section, we can use an
6154 abbreviated form to switch back to it -- unless this section is
6155 part of a COMDAT groups, in which case GAS requires the full
6156 declaration every time. */
6157 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6158 && (flags & SECTION_DECLARED))
6160 fprintf (asm_out_file, "\t.section\t%s\n", name);
6161 return;
6164 if (!(flags & SECTION_DEBUG))
6165 *f++ = 'a';
6166 if (flags & SECTION_EXCLUDE)
6167 *f++ = 'e';
6168 if (flags & SECTION_WRITE)
6169 *f++ = 'w';
6170 if (flags & SECTION_CODE)
6171 *f++ = 'x';
6172 if (flags & SECTION_SMALL)
6173 *f++ = 's';
6174 if (flags & SECTION_MERGE)
6175 *f++ = 'M';
6176 if (flags & SECTION_STRINGS)
6177 *f++ = 'S';
6178 if (flags & SECTION_TLS)
6179 *f++ = TLS_SECTION_ASM_FLAG;
6180 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6181 *f++ = 'G';
6182 *f = '\0';
6184 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6186 if (!(flags & SECTION_NOTYPE))
6188 const char *type;
6189 const char *format;
6191 if (flags & SECTION_BSS)
6192 type = "nobits";
6193 else
6194 type = "progbits";
6196 format = ",@%s";
6197 /* On platforms that use "@" as the assembly comment character,
6198 use "%" instead. */
6199 if (strcmp (ASM_COMMENT_START, "@") == 0)
6200 format = ",%%%s";
6201 fprintf (asm_out_file, format, type);
6203 if (flags & SECTION_ENTSIZE)
6204 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6205 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6207 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6208 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6209 else
6210 fprintf (asm_out_file, ",%s,comdat",
6211 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6215 putc ('\n', asm_out_file);
6218 void
6219 default_coff_asm_named_section (const char *name, unsigned int flags,
6220 tree decl ATTRIBUTE_UNUSED)
6222 char flagchars[8], *f = flagchars;
6224 if (flags & SECTION_WRITE)
6225 *f++ = 'w';
6226 if (flags & SECTION_CODE)
6227 *f++ = 'x';
6228 *f = '\0';
6230 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6233 void
6234 default_pe_asm_named_section (const char *name, unsigned int flags,
6235 tree decl)
6237 default_coff_asm_named_section (name, flags, decl);
6239 if (flags & SECTION_LINKONCE)
6241 /* Functions may have been compiled at various levels of
6242 optimization so we can't use `same_size' here.
6243 Instead, have the linker pick one. */
6244 fprintf (asm_out_file, "\t.linkonce %s\n",
6245 (flags & SECTION_CODE ? "discard" : "same_size"));
6249 /* The lame default section selector. */
6251 section *
6252 default_select_section (tree decl, int reloc,
6253 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6255 if (DECL_P (decl))
6257 if (decl_readonly_section (decl, reloc))
6258 return readonly_data_section;
6260 else if (TREE_CODE (decl) == CONSTRUCTOR)
6262 if (! ((flag_pic && reloc)
6263 || !TREE_READONLY (decl)
6264 || TREE_SIDE_EFFECTS (decl)
6265 || !TREE_CONSTANT (decl)))
6266 return readonly_data_section;
6268 else if (TREE_CODE (decl) == STRING_CST)
6269 return readonly_data_section;
6270 else if (! (flag_pic && reloc))
6271 return readonly_data_section;
6273 return data_section;
6276 enum section_category
6277 categorize_decl_for_section (const_tree decl, int reloc)
6279 enum section_category ret;
6281 if (TREE_CODE (decl) == FUNCTION_DECL)
6282 return SECCAT_TEXT;
6283 else if (TREE_CODE (decl) == STRING_CST)
6285 if ((flag_sanitize & SANITIZE_ADDRESS)
6286 && asan_protect_global (CONST_CAST_TREE (decl)))
6287 /* or !flag_merge_constants */
6288 return SECCAT_RODATA;
6289 else
6290 return SECCAT_RODATA_MERGE_STR;
6292 else if (TREE_CODE (decl) == VAR_DECL)
6294 if (bss_initializer_p (decl))
6295 ret = SECCAT_BSS;
6296 else if (! TREE_READONLY (decl)
6297 || TREE_SIDE_EFFECTS (decl)
6298 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
6300 /* Here the reloc_rw_mask is not testing whether the section should
6301 be read-only or not, but whether the dynamic link will have to
6302 do something. If so, we wish to segregate the data in order to
6303 minimize cache misses inside the dynamic linker. */
6304 if (reloc & targetm.asm_out.reloc_rw_mask ())
6305 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6306 else
6307 ret = SECCAT_DATA;
6309 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6310 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6311 else if (reloc || flag_merge_constants < 2
6312 || ((flag_sanitize & SANITIZE_ADDRESS)
6313 && asan_protect_global (CONST_CAST_TREE (decl))))
6314 /* C and C++ don't allow different variables to share the same
6315 location. -fmerge-all-constants allows even that (at the
6316 expense of not conforming). */
6317 ret = SECCAT_RODATA;
6318 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6319 ret = SECCAT_RODATA_MERGE_STR_INIT;
6320 else
6321 ret = SECCAT_RODATA_MERGE_CONST;
6323 else if (TREE_CODE (decl) == CONSTRUCTOR)
6325 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6326 || TREE_SIDE_EFFECTS (decl)
6327 || ! TREE_CONSTANT (decl))
6328 ret = SECCAT_DATA;
6329 else
6330 ret = SECCAT_RODATA;
6332 else
6333 ret = SECCAT_RODATA;
6335 /* There are no read-only thread-local sections. */
6336 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6338 /* Note that this would be *just* SECCAT_BSS, except that there's
6339 no concept of a read-only thread-local-data section. */
6340 if (ret == SECCAT_BSS
6341 || (flag_zero_initialized_in_bss
6342 && initializer_zerop (DECL_INITIAL (decl))))
6343 ret = SECCAT_TBSS;
6344 else
6345 ret = SECCAT_TDATA;
6348 /* If the target uses small data sections, select it. */
6349 else if (targetm.in_small_data_p (decl))
6351 if (ret == SECCAT_BSS)
6352 ret = SECCAT_SBSS;
6353 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6354 ret = SECCAT_SRODATA;
6355 else
6356 ret = SECCAT_SDATA;
6359 return ret;
6362 static bool
6363 decl_readonly_section_1 (enum section_category category)
6365 switch (category)
6367 case SECCAT_RODATA:
6368 case SECCAT_RODATA_MERGE_STR:
6369 case SECCAT_RODATA_MERGE_STR_INIT:
6370 case SECCAT_RODATA_MERGE_CONST:
6371 case SECCAT_SRODATA:
6372 return true;
6373 default:
6374 return false;
6378 bool
6379 decl_readonly_section (const_tree decl, int reloc)
6381 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6384 /* Select a section based on the above categorization. */
6386 section *
6387 default_elf_select_section (tree decl, int reloc,
6388 unsigned HOST_WIDE_INT align)
6390 const char *sname;
6391 switch (categorize_decl_for_section (decl, reloc))
6393 case SECCAT_TEXT:
6394 /* We're not supposed to be called on FUNCTION_DECLs. */
6395 gcc_unreachable ();
6396 case SECCAT_RODATA:
6397 return readonly_data_section;
6398 case SECCAT_RODATA_MERGE_STR:
6399 return mergeable_string_section (decl, align, 0);
6400 case SECCAT_RODATA_MERGE_STR_INIT:
6401 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6402 case SECCAT_RODATA_MERGE_CONST:
6403 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6404 case SECCAT_SRODATA:
6405 sname = ".sdata2";
6406 break;
6407 case SECCAT_DATA:
6408 return data_section;
6409 case SECCAT_DATA_REL:
6410 sname = ".data.rel";
6411 break;
6412 case SECCAT_DATA_REL_LOCAL:
6413 sname = ".data.rel.local";
6414 break;
6415 case SECCAT_DATA_REL_RO:
6416 sname = ".data.rel.ro";
6417 break;
6418 case SECCAT_DATA_REL_RO_LOCAL:
6419 sname = ".data.rel.ro.local";
6420 break;
6421 case SECCAT_SDATA:
6422 sname = ".sdata";
6423 break;
6424 case SECCAT_TDATA:
6425 sname = ".tdata";
6426 break;
6427 case SECCAT_BSS:
6428 if (bss_section)
6429 return bss_section;
6430 sname = ".bss";
6431 break;
6432 case SECCAT_SBSS:
6433 sname = ".sbss";
6434 break;
6435 case SECCAT_TBSS:
6436 sname = ".tbss";
6437 break;
6438 default:
6439 gcc_unreachable ();
6442 return get_named_section (decl, sname, reloc);
6445 /* Construct a unique section name based on the decl name and the
6446 categorization performed above. */
6448 void
6449 default_unique_section (tree decl, int reloc)
6451 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6452 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6453 const char *prefix, *name, *linkonce;
6454 char *string;
6456 switch (categorize_decl_for_section (decl, reloc))
6458 case SECCAT_TEXT:
6459 prefix = one_only ? ".t" : ".text";
6460 break;
6461 case SECCAT_RODATA:
6462 case SECCAT_RODATA_MERGE_STR:
6463 case SECCAT_RODATA_MERGE_STR_INIT:
6464 case SECCAT_RODATA_MERGE_CONST:
6465 prefix = one_only ? ".r" : ".rodata";
6466 break;
6467 case SECCAT_SRODATA:
6468 prefix = one_only ? ".s2" : ".sdata2";
6469 break;
6470 case SECCAT_DATA:
6471 prefix = one_only ? ".d" : ".data";
6472 break;
6473 case SECCAT_DATA_REL:
6474 prefix = one_only ? ".d.rel" : ".data.rel";
6475 break;
6476 case SECCAT_DATA_REL_LOCAL:
6477 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6478 break;
6479 case SECCAT_DATA_REL_RO:
6480 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6481 break;
6482 case SECCAT_DATA_REL_RO_LOCAL:
6483 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6484 break;
6485 case SECCAT_SDATA:
6486 prefix = one_only ? ".s" : ".sdata";
6487 break;
6488 case SECCAT_BSS:
6489 prefix = one_only ? ".b" : ".bss";
6490 break;
6491 case SECCAT_SBSS:
6492 prefix = one_only ? ".sb" : ".sbss";
6493 break;
6494 case SECCAT_TDATA:
6495 prefix = one_only ? ".td" : ".tdata";
6496 break;
6497 case SECCAT_TBSS:
6498 prefix = one_only ? ".tb" : ".tbss";
6499 break;
6500 default:
6501 gcc_unreachable ();
6504 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
6505 name = targetm.strip_name_encoding (name);
6507 /* If we're using one_only, then there needs to be a .gnu.linkonce
6508 prefix to the section name. */
6509 linkonce = one_only ? ".gnu.linkonce" : "";
6511 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6513 DECL_SECTION_NAME (decl) = build_string (strlen (string), string);
6516 /* Like compute_reloc_for_constant, except for an RTX. The return value
6517 is a mask for which bit 1 indicates a global relocation, and bit 0
6518 indicates a local relocation. */
6520 static int
6521 compute_reloc_for_rtx_1 (rtx *xp, void *data)
6523 int *preloc = (int *) data;
6524 rtx x = *xp;
6526 switch (GET_CODE (x))
6528 case SYMBOL_REF:
6529 *preloc |= SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6530 break;
6531 case LABEL_REF:
6532 *preloc |= 1;
6533 break;
6534 default:
6535 break;
6538 return 0;
6541 static int
6542 compute_reloc_for_rtx (rtx x)
6544 int reloc;
6546 switch (GET_CODE (x))
6548 case CONST:
6549 case SYMBOL_REF:
6550 case LABEL_REF:
6551 reloc = 0;
6552 for_each_rtx (&x, compute_reloc_for_rtx_1, &reloc);
6553 return reloc;
6555 default:
6556 return 0;
6560 section *
6561 default_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
6562 rtx x,
6563 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6565 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6566 return data_section;
6567 else
6568 return readonly_data_section;
6571 section *
6572 default_elf_select_rtx_section (enum machine_mode mode, rtx x,
6573 unsigned HOST_WIDE_INT align)
6575 int reloc = compute_reloc_for_rtx (x);
6577 /* ??? Handle small data here somehow. */
6579 if (reloc & targetm.asm_out.reloc_rw_mask ())
6581 if (reloc == 1)
6582 return get_named_section (NULL, ".data.rel.ro.local", 1);
6583 else
6584 return get_named_section (NULL, ".data.rel.ro", 3);
6587 return mergeable_constant_section (mode, align, 0);
6590 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6592 void
6593 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6595 rtx symbol;
6596 int flags;
6598 /* Careful not to prod global register variables. */
6599 if (!MEM_P (rtl))
6600 return;
6601 symbol = XEXP (rtl, 0);
6602 if (GET_CODE (symbol) != SYMBOL_REF)
6603 return;
6605 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6606 if (TREE_CODE (decl) == FUNCTION_DECL)
6607 flags |= SYMBOL_FLAG_FUNCTION;
6608 if (targetm.binds_local_p (decl))
6609 flags |= SYMBOL_FLAG_LOCAL;
6610 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6611 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6612 else if (targetm.in_small_data_p (decl))
6613 flags |= SYMBOL_FLAG_SMALL;
6614 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6615 being PUBLIC, the thing *must* be defined in this translation unit.
6616 Prevent this buglet from being propagated into rtl code as well. */
6617 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6618 flags |= SYMBOL_FLAG_EXTERNAL;
6620 SYMBOL_REF_FLAGS (symbol) = flags;
6623 /* By default, we do nothing for encode_section_info, so we need not
6624 do anything but discard the '*' marker. */
6626 const char *
6627 default_strip_name_encoding (const char *str)
6629 return str + (*str == '*');
6632 #ifdef ASM_OUTPUT_DEF
6633 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6634 anchor relative to ".", the current section position. */
6636 void
6637 default_asm_output_anchor (rtx symbol)
6639 char buffer[100];
6641 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6642 SYMBOL_REF_BLOCK_OFFSET (symbol));
6643 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6645 #endif
6647 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6649 bool
6650 default_use_anchors_for_symbol_p (const_rtx symbol)
6652 section *sect;
6653 tree decl;
6655 /* Don't use anchors for mergeable sections. The linker might move
6656 the objects around. */
6657 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6658 if (sect->common.flags & SECTION_MERGE)
6659 return false;
6661 /* Don't use anchors for small data sections. The small data register
6662 acts as an anchor for such sections. */
6663 if (sect->common.flags & SECTION_SMALL)
6664 return false;
6666 decl = SYMBOL_REF_DECL (symbol);
6667 if (decl && DECL_P (decl))
6669 /* Don't use section anchors for decls that might be defined or
6670 usurped by other modules. */
6671 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6672 return false;
6674 /* Don't use section anchors for decls that will be placed in a
6675 small data section. */
6676 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6677 one above. The problem is that we only use SECTION_SMALL for
6678 sections that should be marked as small in the section directive. */
6679 if (targetm.in_small_data_p (decl))
6680 return false;
6682 return true;
6685 /* Return true when RESOLUTION indicate that symbol will be bound to the
6686 definition provided by current .o file. */
6688 static bool
6689 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
6691 return (resolution == LDPR_PREVAILING_DEF
6692 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6693 || resolution == LDPR_PREVAILING_DEF_IRONLY);
6696 /* Return true when RESOLUTION indicate that symbol will be bound locally
6697 within current executable or DSO. */
6699 static bool
6700 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
6702 return (resolution == LDPR_PREVAILING_DEF
6703 || resolution == LDPR_PREVAILING_DEF_IRONLY
6704 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6705 || resolution == LDPR_PREEMPTED_REG
6706 || resolution == LDPR_PREEMPTED_IR
6707 || resolution == LDPR_RESOLVED_IR
6708 || resolution == LDPR_RESOLVED_EXEC);
6711 /* Assume ELF-ish defaults, since that's pretty much the most liberal
6712 wrt cross-module name binding. */
6714 bool
6715 default_binds_local_p (const_tree exp)
6717 return default_binds_local_p_1 (exp, flag_shlib);
6720 bool
6721 default_binds_local_p_1 (const_tree exp, int shlib)
6723 bool local_p;
6724 bool resolved_locally = false;
6725 bool resolved_to_local_def = false;
6727 /* With resolution file in hands, take look into resolutions.
6728 We can't just return true for resolved_locally symbols,
6729 because dynamic linking might overwrite symbols
6730 in shared libraries. */
6731 if (TREE_CODE (exp) == VAR_DECL && TREE_PUBLIC (exp)
6732 && (TREE_STATIC (exp) || DECL_EXTERNAL (exp)))
6734 varpool_node *vnode = varpool_get_node (exp);
6735 if (vnode && (resolution_local_p (vnode->resolution) || vnode->in_other_partition))
6736 resolved_locally = true;
6737 if (vnode
6738 && resolution_to_local_definition_p (vnode->resolution))
6739 resolved_to_local_def = true;
6741 else if (TREE_CODE (exp) == FUNCTION_DECL && TREE_PUBLIC (exp))
6743 struct cgraph_node *node = cgraph_get_node (exp);
6744 if (node
6745 && (resolution_local_p (node->resolution) || node->in_other_partition))
6746 resolved_locally = true;
6747 if (node
6748 && resolution_to_local_definition_p (node->resolution))
6749 resolved_to_local_def = true;
6752 /* A non-decl is an entry in the constant pool. */
6753 if (!DECL_P (exp))
6754 local_p = true;
6755 /* Weakrefs may not bind locally, even though the weakref itself is always
6756 static and therefore local. Similarly, the resolver for ifunc functions
6757 might resolve to a non-local function.
6758 FIXME: We can resolve the weakref case more curefuly by looking at the
6759 weakref alias. */
6760 else if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
6761 || (TREE_CODE (exp) == FUNCTION_DECL
6762 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
6763 local_p = false;
6764 /* Static variables are always local. */
6765 else if (! TREE_PUBLIC (exp))
6766 local_p = true;
6767 /* A variable is local if the user has said explicitly that it will
6768 be. */
6769 else if ((DECL_VISIBILITY_SPECIFIED (exp)
6770 || resolved_to_local_def)
6771 && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6772 local_p = true;
6773 /* Variables defined outside this object might not be local. */
6774 else if (DECL_EXTERNAL (exp) && !resolved_locally)
6775 local_p = false;
6776 /* If defined in this object and visibility is not default, must be
6777 local. */
6778 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6779 local_p = true;
6780 /* Default visibility weak data can be overridden by a strong symbol
6781 in another module and so are not local. */
6782 else if (DECL_WEAK (exp)
6783 && !resolved_locally)
6784 local_p = false;
6785 /* If PIC, then assume that any global name can be overridden by
6786 symbols resolved from other modules. */
6787 else if (shlib)
6788 local_p = false;
6789 /* Uninitialized COMMON variable may be unified with symbols
6790 resolved from other modules. */
6791 else if (DECL_COMMON (exp)
6792 && !resolved_locally
6793 && (DECL_INITIAL (exp) == NULL
6794 || DECL_INITIAL (exp) == error_mark_node))
6795 local_p = false;
6796 /* Otherwise we're left with initialized (or non-common) global data
6797 which is of necessity defined locally. */
6798 else
6799 local_p = true;
6801 return local_p;
6804 /* Return true when references to DECL must bind to current definition in
6805 final executable.
6807 The condition is usually equivalent to whether the function binds to the
6808 current module (shared library or executable), that is to binds_local_p.
6809 We use this fact to avoid need for another target hook and implement
6810 the logic using binds_local_p and just special cases where
6811 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
6812 the weak definitions (that can be overwritten at linktime by other
6813 definition from different object file) and when resolution info is available
6814 we simply use the knowledge passed to us by linker plugin. */
6815 bool
6816 decl_binds_to_current_def_p (tree decl)
6818 gcc_assert (DECL_P (decl));
6819 if (!targetm.binds_local_p (decl))
6820 return false;
6821 if (!TREE_PUBLIC (decl))
6822 return true;
6823 /* When resolution is available, just use it. */
6824 if (TREE_CODE (decl) == VAR_DECL
6825 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl)))
6827 varpool_node *vnode = varpool_get_node (decl);
6828 if (vnode
6829 && vnode->resolution != LDPR_UNKNOWN)
6830 return resolution_to_local_definition_p (vnode->resolution);
6832 else if (TREE_CODE (decl) == FUNCTION_DECL)
6834 struct cgraph_node *node = cgraph_get_node (decl);
6835 if (node
6836 && node->resolution != LDPR_UNKNOWN)
6837 return resolution_to_local_definition_p (node->resolution);
6839 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
6840 binds locally but still can be overwritten), DECL_COMMON (can be merged
6841 with a non-common definition somewhere in the same module) or
6842 DECL_EXTERNAL.
6843 This rely on fact that binds_local_p behave as decl_replaceable_p
6844 for all other declaration types. */
6845 if (DECL_WEAK (decl))
6846 return false;
6847 if (DECL_COMMON (decl)
6848 && (DECL_INITIAL (decl) == NULL
6849 || DECL_INITIAL (decl) == error_mark_node))
6850 return false;
6851 if (DECL_EXTERNAL (decl))
6852 return false;
6853 return true;
6856 /* A replaceable function or variable is one which may be replaced
6857 at link-time with an entirely different definition, provided that the
6858 replacement has the same type. For example, functions declared
6859 with __attribute__((weak)) on most systems are replaceable.
6861 COMDAT functions are not replaceable, since all definitions of the
6862 function must be equivalent. It is important that COMDAT functions
6863 not be treated as replaceable so that use of C++ template
6864 instantiations is not penalized. */
6866 bool
6867 decl_replaceable_p (tree decl)
6869 gcc_assert (DECL_P (decl));
6870 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
6871 return false;
6872 return !decl_binds_to_current_def_p (decl);
6875 /* Default function to output code that will globalize a label. A
6876 target must define GLOBAL_ASM_OP or provide its own function to
6877 globalize a label. */
6878 #ifdef GLOBAL_ASM_OP
6879 void
6880 default_globalize_label (FILE * stream, const char *name)
6882 fputs (GLOBAL_ASM_OP, stream);
6883 assemble_name (stream, name);
6884 putc ('\n', stream);
6886 #endif /* GLOBAL_ASM_OP */
6888 /* Default function to output code that will globalize a declaration. */
6889 void
6890 default_globalize_decl_name (FILE * stream, tree decl)
6892 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
6893 targetm.asm_out.globalize_label (stream, name);
6896 /* Default function to output a label for unwind information. The
6897 default is to do nothing. A target that needs nonlocal labels for
6898 unwind information must provide its own function to do this. */
6899 void
6900 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
6901 tree decl ATTRIBUTE_UNUSED,
6902 int for_eh ATTRIBUTE_UNUSED,
6903 int empty ATTRIBUTE_UNUSED)
6907 /* Default function to output a label to divide up the exception table.
6908 The default is to do nothing. A target that needs/wants to divide
6909 up the table must provide it's own function to do this. */
6910 void
6911 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
6915 /* This is how to output an internal numbered label where PREFIX is
6916 the class of label and LABELNO is the number within the class. */
6918 void
6919 default_generate_internal_label (char *buf, const char *prefix,
6920 unsigned long labelno)
6922 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6925 /* This is how to output an internal numbered label where PREFIX is
6926 the class of label and LABELNO is the number within the class. */
6928 void
6929 default_internal_label (FILE *stream, const char *prefix,
6930 unsigned long labelno)
6932 char *const buf = (char *) alloca (40 + strlen (prefix));
6933 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6934 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
6938 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
6940 void
6941 default_asm_declare_constant_name (FILE *file, const char *name,
6942 const_tree exp ATTRIBUTE_UNUSED,
6943 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
6945 assemble_label (file, name);
6948 /* This is the default behavior at the beginning of a file. It's
6949 controlled by two other target-hook toggles. */
6950 void
6951 default_file_start (void)
6953 if (targetm.asm_file_start_app_off
6954 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
6955 fputs (ASM_APP_OFF, asm_out_file);
6957 if (targetm.asm_file_start_file_directive)
6958 output_file_directive (asm_out_file, main_input_filename);
6961 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
6962 which emits a special section directive used to indicate whether or
6963 not this object file needs an executable stack. This is primarily
6964 a GNU extension to ELF but could be used on other targets. */
6966 int trampolines_created;
6968 void
6969 file_end_indicate_exec_stack (void)
6971 unsigned int flags = SECTION_DEBUG;
6972 if (trampolines_created)
6973 flags |= SECTION_CODE;
6975 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
6978 /* Emit a special section directive to indicate that this object file
6979 was compiled with -fsplit-stack. This is used to let the linker
6980 detect calls between split-stack code and non-split-stack code, so
6981 that it can modify the split-stack code to allocate a sufficiently
6982 large stack. We emit another special section if there are any
6983 functions in this file which have the no_split_stack attribute, to
6984 prevent the linker from warning about being unable to convert the
6985 functions if they call non-split-stack code. */
6987 void
6988 file_end_indicate_split_stack (void)
6990 if (flag_split_stack)
6992 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
6993 NULL));
6994 if (saw_no_split_stack)
6995 switch_to_section (get_section (".note.GNU-no-split-stack",
6996 SECTION_DEBUG, NULL));
7000 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
7001 a get_unnamed_section callback. */
7003 void
7004 output_section_asm_op (const void *directive)
7006 fprintf (asm_out_file, "%s\n", (const char *) directive);
7009 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
7010 the current section is NEW_SECTION. */
7012 void
7013 switch_to_section (section *new_section)
7015 if (in_section == new_section)
7016 return;
7018 if (new_section->common.flags & SECTION_FORGET)
7019 in_section = NULL;
7020 else
7021 in_section = new_section;
7023 switch (SECTION_STYLE (new_section))
7025 case SECTION_NAMED:
7026 targetm.asm_out.named_section (new_section->named.name,
7027 new_section->named.common.flags,
7028 new_section->named.decl);
7029 break;
7031 case SECTION_UNNAMED:
7032 new_section->unnamed.callback (new_section->unnamed.data);
7033 break;
7035 case SECTION_NOSWITCH:
7036 gcc_unreachable ();
7037 break;
7040 new_section->common.flags |= SECTION_DECLARED;
7043 /* If block symbol SYMBOL has not yet been assigned an offset, place
7044 it at the end of its block. */
7046 void
7047 place_block_symbol (rtx symbol)
7049 unsigned HOST_WIDE_INT size, mask, offset;
7050 struct constant_descriptor_rtx *desc;
7051 unsigned int alignment;
7052 struct object_block *block;
7053 tree decl;
7055 gcc_assert (SYMBOL_REF_BLOCK (symbol));
7056 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7057 return;
7059 /* Work out the symbol's size and alignment. */
7060 if (CONSTANT_POOL_ADDRESS_P (symbol))
7062 desc = SYMBOL_REF_CONSTANT (symbol);
7063 alignment = desc->align;
7064 size = GET_MODE_SIZE (desc->mode);
7066 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7068 decl = SYMBOL_REF_DECL (symbol);
7069 alignment = DECL_ALIGN (decl);
7070 size = get_constant_size (DECL_INITIAL (decl));
7071 if ((flag_sanitize & SANITIZE_ADDRESS)
7072 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7073 && asan_protect_global (DECL_INITIAL (decl)))
7074 size += asan_red_zone_size (size);
7076 else
7078 decl = SYMBOL_REF_DECL (symbol);
7079 alignment = get_variable_align (decl);
7080 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7081 if ((flag_sanitize & SANITIZE_ADDRESS)
7082 && asan_protect_global (decl))
7084 size += asan_red_zone_size (size);
7085 alignment = MAX (alignment,
7086 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7090 /* Calculate the object's offset from the start of the block. */
7091 block = SYMBOL_REF_BLOCK (symbol);
7092 mask = alignment / BITS_PER_UNIT - 1;
7093 offset = (block->size + mask) & ~mask;
7094 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7096 /* Record the block's new alignment and size. */
7097 block->alignment = MAX (block->alignment, alignment);
7098 block->size = offset + size;
7100 vec_safe_push (block->objects, symbol);
7103 /* Return the anchor that should be used to address byte offset OFFSET
7104 from the first object in BLOCK. MODEL is the TLS model used
7105 to access it. */
7108 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7109 enum tls_model model)
7111 char label[100];
7112 unsigned int begin, middle, end;
7113 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7114 rtx anchor;
7116 /* Work out the anchor's offset. Use an offset of 0 for the first
7117 anchor so that we don't pessimize the case where we take the address
7118 of a variable at the beginning of the block. This is particularly
7119 useful when a block has only one variable assigned to it.
7121 We try to place anchors RANGE bytes apart, so there can then be
7122 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7123 a ptr_mode offset. With some target settings, the lowest such
7124 anchor might be out of range for the lowest ptr_mode offset;
7125 likewise the highest anchor for the highest offset. Use anchors
7126 at the extreme ends of the ptr_mode range in such cases.
7128 All arithmetic uses unsigned integers in order to avoid
7129 signed overflow. */
7130 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7131 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7132 range = max_offset - min_offset + 1;
7133 if (range == 0)
7134 offset = 0;
7135 else
7137 bias = 1 << (GET_MODE_BITSIZE (ptr_mode) - 1);
7138 if (offset < 0)
7140 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7141 delta -= delta % range;
7142 if (delta > bias)
7143 delta = bias;
7144 offset = (HOST_WIDE_INT) (-delta);
7146 else
7148 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7149 delta -= delta % range;
7150 if (delta > bias - 1)
7151 delta = bias - 1;
7152 offset = (HOST_WIDE_INT) delta;
7156 /* Do a binary search to see if there's already an anchor we can use.
7157 Set BEGIN to the new anchor's index if not. */
7158 begin = 0;
7159 end = vec_safe_length (block->anchors);
7160 while (begin != end)
7162 middle = (end + begin) / 2;
7163 anchor = (*block->anchors)[middle];
7164 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7165 end = middle;
7166 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7167 begin = middle + 1;
7168 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7169 end = middle;
7170 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7171 begin = middle + 1;
7172 else
7173 return anchor;
7176 /* Create a new anchor with a unique label. */
7177 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7178 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7179 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7180 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7182 /* Insert it at index BEGIN. */
7183 vec_safe_insert (block->anchors, begin, anchor);
7184 return anchor;
7187 /* Output the objects in BLOCK. */
7189 static void
7190 output_object_block (struct object_block *block)
7192 struct constant_descriptor_rtx *desc;
7193 unsigned int i;
7194 HOST_WIDE_INT offset;
7195 tree decl;
7196 rtx symbol;
7198 if (!block->objects)
7199 return;
7201 /* Switch to the section and make sure that the first byte is
7202 suitably aligned. */
7203 switch_to_section (block->sect);
7204 assemble_align (block->alignment);
7206 /* Define the values of all anchors relative to the current section
7207 position. */
7208 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7209 targetm.asm_out.output_anchor (symbol);
7211 /* Output the objects themselves. */
7212 offset = 0;
7213 FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7215 /* Move to the object's offset, padding with zeros if necessary. */
7216 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7217 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7218 if (CONSTANT_POOL_ADDRESS_P (symbol))
7220 desc = SYMBOL_REF_CONSTANT (symbol);
7221 output_constant_pool_1 (desc, 1);
7222 offset += GET_MODE_SIZE (desc->mode);
7224 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7226 HOST_WIDE_INT size;
7227 decl = SYMBOL_REF_DECL (symbol);
7228 assemble_constant_contents (DECL_INITIAL (decl), XSTR (symbol, 0),
7229 DECL_ALIGN (decl));
7230 size = get_constant_size (DECL_INITIAL (decl));
7231 offset += size;
7232 if ((flag_sanitize & SANITIZE_ADDRESS)
7233 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7234 && asan_protect_global (DECL_INITIAL (decl)))
7236 size = asan_red_zone_size (size);
7237 assemble_zeros (size);
7238 offset += size;
7241 else
7243 HOST_WIDE_INT size;
7244 decl = SYMBOL_REF_DECL (symbol);
7245 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7246 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7247 offset += size;
7248 if ((flag_sanitize & SANITIZE_ADDRESS)
7249 && asan_protect_global (decl))
7251 size = asan_red_zone_size (size);
7252 assemble_zeros (size);
7253 offset += size;
7259 /* A htab_traverse callback used to call output_object_block for
7260 each member of object_block_htab. */
7262 static int
7263 output_object_block_htab (void **slot, void *data ATTRIBUTE_UNUSED)
7265 output_object_block ((struct object_block *) (*slot));
7266 return 1;
7269 /* Output the definitions of all object_blocks. */
7271 void
7272 output_object_blocks (void)
7274 htab_traverse (object_block_htab, output_object_block_htab, NULL);
7277 /* This function provides a possible implementation of the
7278 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7279 by -frecord-gcc-switches it creates a new mergeable, string section in the
7280 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7281 contains the switches in ASCII format.
7283 FIXME: This code does not correctly handle double quote characters
7284 that appear inside strings, (it strips them rather than preserving them).
7285 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7286 characters - instead it treats them as sub-string separators. Since
7287 we want to emit NUL strings terminators into the object file we have to use
7288 ASM_OUTPUT_SKIP. */
7291 elf_record_gcc_switches (print_switch_type type, const char * name)
7293 switch (type)
7295 case SWITCH_TYPE_PASSED:
7296 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7297 ASM_OUTPUT_SKIP (asm_out_file, (unsigned HOST_WIDE_INT) 1);
7298 break;
7300 case SWITCH_TYPE_DESCRIPTIVE:
7301 if (name == NULL)
7303 /* Distinguish between invocations where name is NULL. */
7304 static bool started = false;
7306 if (!started)
7308 section * sec;
7310 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7311 SECTION_DEBUG
7312 | SECTION_MERGE
7313 | SECTION_STRINGS
7314 | (SECTION_ENTSIZE & 1),
7315 NULL);
7316 switch_to_section (sec);
7317 started = true;
7321 default:
7322 break;
7325 /* The return value is currently ignored by the caller, but must be 0.
7326 For -fverbose-asm the return value would be the number of characters
7327 emitted into the assembler file. */
7328 return 0;
7331 /* Emit text to declare externally defined symbols. It is needed to
7332 properly support non-default visibility. */
7333 void
7334 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7335 tree decl,
7336 const char *name ATTRIBUTE_UNUSED)
7338 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7339 set in order to avoid putting out names that are never really
7340 used. */
7341 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7342 && targetm.binds_local_p (decl))
7343 maybe_assemble_visibility (decl);
7346 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7348 void
7349 default_asm_output_source_filename (FILE *file, const char *name)
7351 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7352 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7353 #else
7354 fprintf (file, "\t.file\t");
7355 output_quoted_string (file, name);
7356 putc ('\n', file);
7357 #endif
7360 /* Output a file name in the form wanted by System V. */
7362 void
7363 output_file_directive (FILE *asm_file, const char *input_name)
7365 int len;
7366 const char *na;
7368 if (input_name == NULL)
7369 input_name = "<stdin>";
7370 else
7371 input_name = remap_debug_filename (input_name);
7373 len = strlen (input_name);
7374 na = input_name + len;
7376 /* NA gets INPUT_NAME sans directory names. */
7377 while (na > input_name)
7379 if (IS_DIR_SEPARATOR (na[-1]))
7380 break;
7381 na--;
7384 targetm.asm_out.output_source_filename (asm_file, na);
7387 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7388 EXP. */
7390 make_debug_expr_from_rtl (const_rtx exp)
7392 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7393 enum machine_mode mode = GET_MODE (exp);
7394 rtx dval;
7396 DECL_ARTIFICIAL (ddecl) = 1;
7397 if (REG_P (exp) && REG_EXPR (exp))
7398 type = TREE_TYPE (REG_EXPR (exp));
7399 else if (MEM_P (exp) && MEM_EXPR (exp))
7400 type = TREE_TYPE (MEM_EXPR (exp));
7401 else
7402 type = NULL_TREE;
7403 if (type && TYPE_MODE (type) == mode)
7404 TREE_TYPE (ddecl) = type;
7405 else
7406 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7407 DECL_MODE (ddecl) = mode;
7408 dval = gen_rtx_DEBUG_EXPR (mode);
7409 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7410 SET_DECL_RTL (ddecl, dval);
7411 return dval;
7414 #ifdef ELF_ASCII_ESCAPES
7415 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7417 void
7418 default_elf_asm_output_limited_string (FILE *f, const char *s)
7420 int escape;
7421 unsigned char c;
7423 fputs (STRING_ASM_OP, f);
7424 putc ('"', f);
7425 while (*s != '\0')
7427 c = *s;
7428 escape = ELF_ASCII_ESCAPES[c];
7429 switch (escape)
7431 case 0:
7432 putc (c, f);
7433 break;
7434 case 1:
7435 /* TODO: Print in hex with fast function, important for -flto. */
7436 fprintf (f, "\\%03o", c);
7437 break;
7438 default:
7439 putc ('\\', f);
7440 putc (escape, f);
7441 break;
7443 s++;
7445 putc ('\"', f);
7446 putc ('\n', f);
7449 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7451 void
7452 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7454 const char *limit = s + len;
7455 const char *last_null = NULL;
7456 unsigned bytes_in_chunk = 0;
7457 unsigned char c;
7458 int escape;
7460 for (; s < limit; s++)
7462 const char *p;
7464 if (bytes_in_chunk >= 60)
7466 putc ('\"', f);
7467 putc ('\n', f);
7468 bytes_in_chunk = 0;
7471 if (s > last_null)
7473 for (p = s; p < limit && *p != '\0'; p++)
7474 continue;
7475 last_null = p;
7477 else
7478 p = last_null;
7480 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7482 if (bytes_in_chunk > 0)
7484 putc ('\"', f);
7485 putc ('\n', f);
7486 bytes_in_chunk = 0;
7489 default_elf_asm_output_limited_string (f, s);
7490 s = p;
7492 else
7494 if (bytes_in_chunk == 0)
7495 fputs (ASCII_DATA_ASM_OP "\"", f);
7497 c = *s;
7498 escape = ELF_ASCII_ESCAPES[c];
7499 switch (escape)
7501 case 0:
7502 putc (c, f);
7503 bytes_in_chunk++;
7504 break;
7505 case 1:
7506 /* TODO: Print in hex with fast function, important for -flto. */
7507 fprintf (f, "\\%03o", c);
7508 bytes_in_chunk += 4;
7509 break;
7510 default:
7511 putc ('\\', f);
7512 putc (escape, f);
7513 bytes_in_chunk += 2;
7514 break;
7520 if (bytes_in_chunk > 0)
7522 putc ('\"', f);
7523 putc ('\n', f);
7526 #endif
7528 static GTY(()) section *elf_init_array_section;
7529 static GTY(()) section *elf_fini_array_section;
7531 static section *
7532 get_elf_initfini_array_priority_section (int priority,
7533 bool constructor_p)
7535 section *sec;
7536 if (priority != DEFAULT_INIT_PRIORITY)
7538 char buf[18];
7539 sprintf (buf, "%s.%.5u",
7540 constructor_p ? ".init_array" : ".fini_array",
7541 priority);
7542 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7544 else
7546 if (constructor_p)
7548 if (elf_init_array_section == NULL)
7549 elf_init_array_section
7550 = get_section (".init_array",
7551 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7552 sec = elf_init_array_section;
7554 else
7556 if (elf_fini_array_section == NULL)
7557 elf_fini_array_section
7558 = get_section (".fini_array",
7559 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7560 sec = elf_fini_array_section;
7563 return sec;
7566 /* Use .init_array section for constructors. */
7568 void
7569 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7571 section *sec = get_elf_initfini_array_priority_section (priority,
7572 true);
7573 assemble_addr_to_section (symbol, sec);
7576 /* Use .fini_array section for destructors. */
7578 void
7579 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7581 section *sec = get_elf_initfini_array_priority_section (priority,
7582 false);
7583 assemble_addr_to_section (symbol, sec);
7586 /* Default TARGET_ASM_OUTPUT_IDENT hook.
7588 This is a bit of a cheat. The real default is a no-op, but this
7589 hook is the default for all targets with a .ident directive. */
7591 void
7592 default_asm_output_ident_directive (const char *ident_str)
7594 const char *ident_asm_op = "\t.ident\t";
7596 /* If we are still in the front end, do not write out the string
7597 to asm_out_file. Instead, add a fake top-level asm statement.
7598 This allows the front ends to use this hook without actually
7599 writing to asm_out_file, to handle #ident or Pragma Ident. */
7600 if (cgraph_state == CGRAPH_STATE_PARSING)
7602 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
7603 add_asm_node (build_string (strlen (buf), buf));
7605 else
7606 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
7609 #include "gt-varasm.h"