gcc/testsuite/
[official-gcc.git] / gcc / varasm.c
blob67810960a6e7ec730c6a9583cb83030291114546
1 /* Output variables, constants and external declarations, for GNU compiler.
2 Copyright (C) 1987-2014 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
21 /* This file handles generation of all the assembler code
22 *except* the instructions of a function.
23 This includes declarations of variables and their initial values.
25 We also output the assembler code for constants stored in memory
26 and are responsible for combining constants with the same value. */
28 #include "config.h"
29 #include "system.h"
30 #include "coretypes.h"
31 #include "tm.h"
32 #include "rtl.h"
33 #include "tree.h"
34 #include "stor-layout.h"
35 #include "stringpool.h"
36 #include "gcc-symtab.h"
37 #include "varasm.h"
38 #include "flags.h"
39 #include "function.h"
40 #include "expr.h"
41 #include "hard-reg-set.h"
42 #include "regs.h"
43 #include "output.h"
44 #include "diagnostic-core.h"
45 #include "hashtab.h"
46 #include "ggc.h"
47 #include "langhooks.h"
48 #include "tm_p.h"
49 #include "debug.h"
50 #include "target.h"
51 #include "common/common-target.h"
52 #include "targhooks.h"
53 #include "cgraph.h"
54 #include "pointer-set.h"
55 #include "asan.h"
56 #include "basic-block.h"
58 #ifdef XCOFF_DEBUGGING_INFO
59 #include "xcoffout.h" /* Needed for external data
60 declarations for e.g. AIX 4.x. */
61 #endif
63 /* The (assembler) name of the first globally-visible object output. */
64 extern GTY(()) const char *first_global_object_name;
65 extern GTY(()) const char *weak_global_object_name;
67 const char *first_global_object_name;
68 const char *weak_global_object_name;
70 struct addr_const;
71 struct constant_descriptor_rtx;
72 struct rtx_constant_pool;
74 #define n_deferred_constants (crtl->varasm.deferred_constants)
76 /* Number for making the label on the next
77 constant that is stored in memory. */
79 static GTY(()) int const_labelno;
81 /* Carry information from ASM_DECLARE_OBJECT_NAME
82 to ASM_FINISH_DECLARE_OBJECT. */
84 int size_directive_output;
86 /* The last decl for which assemble_variable was called,
87 if it did ASM_DECLARE_OBJECT_NAME.
88 If the last call to assemble_variable didn't do that,
89 this holds 0. */
91 tree last_assemble_variable_decl;
93 /* The following global variable indicates if the first basic block
94 in a function belongs to the cold partition or not. */
96 bool first_function_block_is_cold;
98 /* We give all constants their own alias set. Perhaps redundant with
99 MEM_READONLY_P, but pre-dates it. */
101 static alias_set_type const_alias_set;
103 /* Whether we saw any functions with no_split_stack. */
105 static bool saw_no_split_stack;
107 static const char *strip_reg_name (const char *);
108 static int contains_pointers_p (tree);
109 #ifdef ASM_OUTPUT_EXTERNAL
110 static bool incorporeal_function_p (tree);
111 #endif
112 static void decode_addr_const (tree, struct addr_const *);
113 static hashval_t const_desc_hash (const void *);
114 static int const_desc_eq (const void *, const void *);
115 static hashval_t const_hash_1 (const tree);
116 static int compare_constant (const tree, const tree);
117 static tree copy_constant (tree);
118 static void output_constant_def_contents (rtx);
119 static void output_addressed_constants (tree);
120 static unsigned HOST_WIDE_INT output_constant (tree, unsigned HOST_WIDE_INT,
121 unsigned int);
122 static void globalize_decl (tree);
123 static bool decl_readonly_section_1 (enum section_category);
124 #ifdef BSS_SECTION_ASM_OP
125 #ifdef ASM_OUTPUT_ALIGNED_BSS
126 static void asm_output_aligned_bss (FILE *, tree, const char *,
127 unsigned HOST_WIDE_INT, int)
128 ATTRIBUTE_UNUSED;
129 #endif
130 #endif /* BSS_SECTION_ASM_OP */
131 static void mark_weak (tree);
132 static void output_constant_pool (const char *, tree);
134 /* Well-known sections, each one associated with some sort of *_ASM_OP. */
135 section *text_section;
136 section *data_section;
137 section *readonly_data_section;
138 section *sdata_section;
139 section *ctors_section;
140 section *dtors_section;
141 section *bss_section;
142 section *sbss_section;
144 /* Various forms of common section. All are guaranteed to be nonnull. */
145 section *tls_comm_section;
146 section *comm_section;
147 section *lcomm_section;
149 /* A SECTION_NOSWITCH section used for declaring global BSS variables.
150 May be null. */
151 section *bss_noswitch_section;
153 /* The section that holds the main exception table, when known. The section
154 is set either by the target's init_sections hook or by the first call to
155 switch_to_exception_section. */
156 section *exception_section;
158 /* The section that holds the DWARF2 frame unwind information, when known.
159 The section is set either by the target's init_sections hook or by the
160 first call to switch_to_eh_frame_section. */
161 section *eh_frame_section;
163 /* asm_out_file's current section. This is NULL if no section has yet
164 been selected or if we lose track of what the current section is. */
165 section *in_section;
167 /* True if code for the current function is currently being directed
168 at the cold section. */
169 bool in_cold_section_p;
171 /* A linked list of all the unnamed sections. */
172 static GTY(()) section *unnamed_sections;
174 /* Return a nonzero value if DECL has a section attribute. */
175 #define IN_NAMED_SECTION(DECL) \
176 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \
177 && DECL_SECTION_NAME (DECL) != NULL_TREE)
179 /* Hash table of named sections. */
180 static GTY((param_is (section))) htab_t section_htab;
182 /* A table of object_blocks, indexed by section. */
183 static GTY((param_is (struct object_block))) htab_t object_block_htab;
185 /* The next number to use for internal anchor labels. */
186 static GTY(()) int anchor_labelno;
188 /* A pool of constants that can be shared between functions. */
189 static GTY(()) struct rtx_constant_pool *shared_constant_pool;
191 /* Helper routines for maintaining section_htab. */
193 static int
194 section_entry_eq (const void *p1, const void *p2)
196 const section *old = (const section *) p1;
197 const char *new_name = (const char *) p2;
199 return strcmp (old->named.name, new_name) == 0;
202 static hashval_t
203 section_entry_hash (const void *p)
205 const section *old = (const section *) p;
206 return htab_hash_string (old->named.name);
209 /* Return a hash value for section SECT. */
211 static hashval_t
212 hash_section (section *sect)
214 if (sect->common.flags & SECTION_NAMED)
215 return htab_hash_string (sect->named.name);
216 return sect->common.flags;
219 /* Helper routines for maintaining object_block_htab. */
221 static int
222 object_block_entry_eq (const void *p1, const void *p2)
224 const struct object_block *old = (const struct object_block *) p1;
225 const section *new_section = (const section *) p2;
227 return old->sect == new_section;
230 static hashval_t
231 object_block_entry_hash (const void *p)
233 const struct object_block *old = (const struct object_block *) p;
234 return hash_section (old->sect);
237 /* Return a new unnamed section with the given fields. */
239 section *
240 get_unnamed_section (unsigned int flags, void (*callback) (const void *),
241 const void *data)
243 section *sect;
245 sect = ggc_alloc<section> ();
246 sect->unnamed.common.flags = flags | SECTION_UNNAMED;
247 sect->unnamed.callback = callback;
248 sect->unnamed.data = data;
249 sect->unnamed.next = unnamed_sections;
251 unnamed_sections = sect;
252 return sect;
255 /* Return a SECTION_NOSWITCH section with the given fields. */
257 static section *
258 get_noswitch_section (unsigned int flags, noswitch_section_callback callback)
260 section *sect;
262 sect = ggc_alloc<section> ();
263 sect->noswitch.common.flags = flags | SECTION_NOSWITCH;
264 sect->noswitch.callback = callback;
266 return sect;
269 /* Return the named section structure associated with NAME. Create
270 a new section with the given fields if no such structure exists. */
272 section *
273 get_section (const char *name, unsigned int flags, tree decl)
275 section *sect, **slot;
277 slot = (section **)
278 htab_find_slot_with_hash (section_htab, name,
279 htab_hash_string (name), INSERT);
280 flags |= SECTION_NAMED;
281 if (*slot == NULL)
283 sect = ggc_alloc<section> ();
284 sect->named.common.flags = flags;
285 sect->named.name = ggc_strdup (name);
286 sect->named.decl = decl;
287 *slot = sect;
289 else
291 sect = *slot;
292 if ((sect->common.flags & ~SECTION_DECLARED) != flags
293 && ((sect->common.flags | flags) & SECTION_OVERRIDE) == 0)
295 /* It is fine if one of the section flags is
296 SECTION_WRITE | SECTION_RELRO and the other has none of these
297 flags (i.e. read-only) in named sections and either the
298 section hasn't been declared yet or has been declared as writable.
299 In that case just make sure the resulting flags are
300 SECTION_WRITE | SECTION_RELRO, ie. writable only because of
301 relocations. */
302 if (((sect->common.flags ^ flags) & (SECTION_WRITE | SECTION_RELRO))
303 == (SECTION_WRITE | SECTION_RELRO)
304 && (sect->common.flags
305 & ~(SECTION_DECLARED | SECTION_WRITE | SECTION_RELRO))
306 == (flags & ~(SECTION_WRITE | SECTION_RELRO))
307 && ((sect->common.flags & SECTION_DECLARED) == 0
308 || (sect->common.flags & SECTION_WRITE)))
310 sect->common.flags |= (SECTION_WRITE | SECTION_RELRO);
311 return sect;
313 /* Sanity check user variables for flag changes. */
314 if (sect->named.decl != NULL
315 && DECL_P (sect->named.decl)
316 && decl != sect->named.decl)
318 if (decl != NULL && DECL_P (decl))
319 error ("%+D causes a section type conflict with %D",
320 decl, sect->named.decl);
321 else
322 error ("section type conflict with %D", sect->named.decl);
323 inform (DECL_SOURCE_LOCATION (sect->named.decl),
324 "%qD was declared here", sect->named.decl);
326 else if (decl != NULL && DECL_P (decl))
327 error ("%+D causes a section type conflict", decl);
328 else
329 error ("section type conflict");
330 /* Make sure we don't error about one section multiple times. */
331 sect->common.flags |= SECTION_OVERRIDE;
334 return sect;
337 /* Return true if the current compilation mode benefits from having
338 objects grouped into blocks. */
340 static bool
341 use_object_blocks_p (void)
343 return flag_section_anchors;
346 /* Return the object_block structure for section SECT. Create a new
347 structure if we haven't created one already. Return null if SECT
348 itself is null. */
350 static struct object_block *
351 get_block_for_section (section *sect)
353 struct object_block *block;
354 void **slot;
356 if (sect == NULL)
357 return NULL;
359 slot = htab_find_slot_with_hash (object_block_htab, sect,
360 hash_section (sect), INSERT);
361 block = (struct object_block *) *slot;
362 if (block == NULL)
364 block = ggc_cleared_alloc<object_block> ();
365 block->sect = sect;
366 *slot = block;
368 return block;
371 /* Create a symbol with label LABEL and place it at byte offset
372 OFFSET in BLOCK. OFFSET can be negative if the symbol's offset
373 is not yet known. LABEL must be a garbage-collected string. */
375 static rtx
376 create_block_symbol (const char *label, struct object_block *block,
377 HOST_WIDE_INT offset)
379 rtx symbol;
380 unsigned int size;
382 /* Create the extended SYMBOL_REF. */
383 size = RTX_HDR_SIZE + sizeof (struct block_symbol);
384 symbol = (rtx) ggc_internal_alloc (size);
386 /* Initialize the normal SYMBOL_REF fields. */
387 memset (symbol, 0, size);
388 PUT_CODE (symbol, SYMBOL_REF);
389 PUT_MODE (symbol, Pmode);
390 XSTR (symbol, 0) = label;
391 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_HAS_BLOCK_INFO;
393 /* Initialize the block_symbol stuff. */
394 SYMBOL_REF_BLOCK (symbol) = block;
395 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
397 return symbol;
400 /* Return a section with a particular name and with whatever SECTION_*
401 flags section_type_flags deems appropriate. The name of the section
402 is taken from NAME if nonnull, otherwise it is taken from DECL's
403 DECL_SECTION_NAME. DECL is the decl associated with the section
404 (see the section comment for details) and RELOC is as for
405 section_type_flags. */
407 section *
408 get_named_section (tree decl, const char *name, int reloc)
410 unsigned int flags;
412 if (name == NULL)
414 gcc_assert (decl && DECL_P (decl) && DECL_SECTION_NAME (decl));
415 name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
418 flags = targetm.section_type_flags (decl, name, reloc);
419 return get_section (name, flags, decl);
422 /* If required, set DECL_SECTION_NAME to a unique name. */
424 void
425 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
426 int flag_function_or_data_sections)
428 if (DECL_SECTION_NAME (decl) == NULL_TREE
429 && targetm_common.have_named_sections
430 && (flag_function_or_data_sections
431 || DECL_COMDAT_GROUP (decl)))
433 targetm.asm_out.unique_section (decl, reloc);
434 DECL_HAS_IMPLICIT_SECTION_NAME_P (decl) = true;
438 #ifdef BSS_SECTION_ASM_OP
440 #ifdef ASM_OUTPUT_ALIGNED_BSS
442 /* Utility function for targets to use in implementing
443 ASM_OUTPUT_ALIGNED_BSS.
444 ??? It is believed that this function will work in most cases so such
445 support is localized here. */
447 static void
448 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
449 const char *name, unsigned HOST_WIDE_INT size,
450 int align)
452 switch_to_section (bss_section);
453 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
454 #ifdef ASM_DECLARE_OBJECT_NAME
455 last_assemble_variable_decl = decl;
456 ASM_DECLARE_OBJECT_NAME (file, name, decl);
457 #else
458 /* Standard thing is just output label for the object. */
459 ASM_OUTPUT_LABEL (file, name);
460 #endif /* ASM_DECLARE_OBJECT_NAME */
461 ASM_OUTPUT_SKIP (file, size ? size : 1);
464 #endif
466 #endif /* BSS_SECTION_ASM_OP */
468 #ifndef USE_SELECT_SECTION_FOR_FUNCTIONS
469 /* Return the hot section for function DECL. Return text_section for
470 null DECLs. */
472 static section *
473 hot_function_section (tree decl)
475 if (decl != NULL_TREE
476 && DECL_SECTION_NAME (decl) != NULL_TREE
477 && targetm_common.have_named_sections)
478 return get_named_section (decl, NULL, 0);
479 else
480 return text_section;
482 #endif
484 /* Return section for TEXT_SECTION_NAME if DECL or DECL_SECTION_NAME (DECL)
485 is NULL.
487 When DECL_SECTION_NAME is non-NULL and it is implicit section and
488 NAMED_SECTION_SUFFIX is non-NULL, then produce section called
489 concatenate the name with NAMED_SECTION_SUFFIX.
490 Otherwise produce "TEXT_SECTION_NAME.IMPLICIT_NAME". */
492 section *
493 get_named_text_section (tree decl,
494 const char *text_section_name,
495 const char *named_section_suffix)
497 if (decl && DECL_SECTION_NAME (decl))
499 if (named_section_suffix)
501 tree dsn = DECL_SECTION_NAME (decl);
502 const char *stripped_name;
503 char *name, *buffer;
505 name = (char *) alloca (TREE_STRING_LENGTH (dsn) + 1);
506 memcpy (name, TREE_STRING_POINTER (dsn),
507 TREE_STRING_LENGTH (dsn) + 1);
509 stripped_name = targetm.strip_name_encoding (name);
511 buffer = ACONCAT ((stripped_name, named_section_suffix, NULL));
512 return get_named_section (decl, buffer, 0);
514 else if (DECL_HAS_IMPLICIT_SECTION_NAME_P (decl))
516 const char *name;
518 /* Do not try to split gnu_linkonce functions. This gets somewhat
519 slipperly. */
520 if (DECL_COMDAT_GROUP (decl) && !HAVE_COMDAT_GROUP)
521 return NULL;
522 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
523 name = targetm.strip_name_encoding (name);
524 return get_named_section (decl, ACONCAT ((text_section_name, ".",
525 name, NULL)), 0);
527 else
528 return NULL;
530 return get_named_section (decl, text_section_name, 0);
533 /* Choose named function section based on its frequency. */
535 section *
536 default_function_section (tree decl, enum node_frequency freq,
537 bool startup, bool exit)
539 #if defined HAVE_LD_EH_GC_SECTIONS && defined HAVE_LD_EH_GC_SECTIONS_BUG
540 /* Old GNU linkers have buggy --gc-section support, which sometimes
541 results in .gcc_except_table* sections being garbage collected. */
542 if (decl
543 && DECL_SECTION_NAME (decl)
544 && DECL_HAS_IMPLICIT_SECTION_NAME_P (decl))
545 return NULL;
546 #endif
548 if (!flag_reorder_functions
549 || !targetm_common.have_named_sections)
550 return NULL;
551 /* Startup code should go to startup subsection unless it is
552 unlikely executed (this happens especially with function splitting
553 where we can split away unnecessary parts of static constructors. */
554 if (startup && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
556 /* If we do have a profile or(and) LTO phase is executed, we do not need
557 these ELF section. */
558 if (!in_lto_p || !flag_profile_values)
559 return get_named_text_section (decl, ".text.startup", NULL);
560 else
561 return NULL;
564 /* Similarly for exit. */
565 if (exit && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
566 return get_named_text_section (decl, ".text.exit", NULL);
568 /* Group cold functions together, similarly for hot code. */
569 switch (freq)
571 case NODE_FREQUENCY_UNLIKELY_EXECUTED:
572 return get_named_text_section (decl, ".text.unlikely", NULL);
573 case NODE_FREQUENCY_HOT:
574 /* If we do have a profile or(and) LTO phase is executed, we do not need
575 these ELF section. */
576 if (!in_lto_p || !flag_profile_values)
577 return get_named_text_section (decl, ".text.hot", NULL);
578 default:
579 return NULL;
583 /* Return the section for function DECL.
585 If DECL is NULL_TREE, return the text section. We can be passed
586 NULL_TREE under some circumstances by dbxout.c at least.
588 If FORCE_COLD is true, return cold function section ignoring
589 the frequency info of cgraph_node. */
591 static section *
592 function_section_1 (tree decl, bool force_cold)
594 section *section = NULL;
595 enum node_frequency freq = NODE_FREQUENCY_NORMAL;
596 bool startup = false, exit = false;
598 if (decl)
600 struct cgraph_node *node = cgraph_get_node (decl);
602 if (node)
604 freq = node->frequency;
605 startup = node->only_called_at_startup;
606 exit = node->only_called_at_exit;
609 if (force_cold)
610 freq = NODE_FREQUENCY_UNLIKELY_EXECUTED;
612 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
613 if (decl != NULL_TREE
614 && DECL_SECTION_NAME (decl) != NULL_TREE)
616 if (targetm.asm_out.function_section)
617 section = targetm.asm_out.function_section (decl, freq,
618 startup, exit);
619 if (section)
620 return section;
621 return get_named_section (decl, NULL, 0);
623 else
624 return targetm.asm_out.select_section
625 (decl, freq == NODE_FREQUENCY_UNLIKELY_EXECUTED,
626 DECL_ALIGN (decl));
627 #else
628 if (targetm.asm_out.function_section)
629 section = targetm.asm_out.function_section (decl, freq, startup, exit);
630 if (section)
631 return section;
632 return hot_function_section (decl);
633 #endif
636 /* Return the section for function DECL.
638 If DECL is NULL_TREE, return the text section. We can be passed
639 NULL_TREE under some circumstances by dbxout.c at least. */
641 section *
642 function_section (tree decl)
644 /* Handle cases where function splitting code decides
645 to put function entry point into unlikely executed section
646 despite the fact that the function itself is not cold
647 (i.e. it is called rarely but contains a hot loop that is
648 better to live in hot subsection for the code locality). */
649 return function_section_1 (decl,
650 first_function_block_is_cold);
653 /* Return the section for the current function, take IN_COLD_SECTION_P
654 into account. */
656 section *
657 current_function_section (void)
659 return function_section_1 (current_function_decl, in_cold_section_p);
662 /* Tell assembler to switch to unlikely-to-be-executed text section. */
664 section *
665 unlikely_text_section (void)
667 return function_section_1 (current_function_decl, true);
670 /* When called within a function context, return true if the function
671 has been assigned a cold text section and if SECT is that section.
672 When called outside a function context, return true if SECT is the
673 default cold section. */
675 bool
676 unlikely_text_section_p (section *sect)
678 return sect == function_section_1 (current_function_decl, true);
681 /* Return the read-only data section associated with function DECL. */
683 section *
684 default_function_rodata_section (tree decl)
686 if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
688 const char *name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
690 if (DECL_COMDAT_GROUP (decl) && HAVE_COMDAT_GROUP)
692 const char *dot;
693 size_t len;
694 char* rname;
696 dot = strchr (name + 1, '.');
697 if (!dot)
698 dot = name;
699 len = strlen (dot) + 8;
700 rname = (char *) alloca (len);
702 strcpy (rname, ".rodata");
703 strcat (rname, dot);
704 return get_section (rname, SECTION_LINKONCE, decl);
706 /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo. */
707 else if (DECL_COMDAT_GROUP (decl)
708 && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
710 size_t len = strlen (name) + 1;
711 char *rname = (char *) alloca (len);
713 memcpy (rname, name, len);
714 rname[14] = 'r';
715 return get_section (rname, SECTION_LINKONCE, decl);
717 /* For .text.foo we want to use .rodata.foo. */
718 else if (flag_function_sections && flag_data_sections
719 && strncmp (name, ".text.", 6) == 0)
721 size_t len = strlen (name) + 1;
722 char *rname = (char *) alloca (len + 2);
724 memcpy (rname, ".rodata", 7);
725 memcpy (rname + 7, name + 5, len - 5);
726 return get_section (rname, 0, decl);
730 return readonly_data_section;
733 /* Return the read-only data section associated with function DECL
734 for targets where that section should be always the single
735 readonly data section. */
737 section *
738 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
740 return readonly_data_section;
743 /* Return the section to use for string merging. */
745 static section *
746 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
747 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
748 unsigned int flags ATTRIBUTE_UNUSED)
750 HOST_WIDE_INT len;
752 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
753 && TREE_CODE (decl) == STRING_CST
754 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
755 && align <= 256
756 && (len = int_size_in_bytes (TREE_TYPE (decl))) > 0
757 && TREE_STRING_LENGTH (decl) >= len)
759 enum machine_mode mode;
760 unsigned int modesize;
761 const char *str;
762 HOST_WIDE_INT i;
763 int j, unit;
764 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
765 char *name = (char *) alloca (strlen (prefix) + 30);
767 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
768 modesize = GET_MODE_BITSIZE (mode);
769 if (modesize >= 8 && modesize <= 256
770 && (modesize & (modesize - 1)) == 0)
772 if (align < modesize)
773 align = modesize;
775 str = TREE_STRING_POINTER (decl);
776 unit = GET_MODE_SIZE (mode);
778 /* Check for embedded NUL characters. */
779 for (i = 0; i < len; i += unit)
781 for (j = 0; j < unit; j++)
782 if (str[i + j] != '\0')
783 break;
784 if (j == unit)
785 break;
787 if (i == len - unit)
789 sprintf (name, "%s.str%d.%d", prefix,
790 modesize / 8, (int) (align / 8));
791 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
792 return get_section (name, flags, NULL);
797 return readonly_data_section;
800 /* Return the section to use for constant merging. */
802 section *
803 mergeable_constant_section (enum machine_mode mode ATTRIBUTE_UNUSED,
804 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
805 unsigned int flags ATTRIBUTE_UNUSED)
807 unsigned int modesize = GET_MODE_BITSIZE (mode);
809 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
810 && mode != VOIDmode
811 && mode != BLKmode
812 && modesize <= align
813 && align >= 8
814 && align <= 256
815 && (align & (align - 1)) == 0)
817 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
818 char *name = (char *) alloca (strlen (prefix) + 30);
820 sprintf (name, "%s.cst%d", prefix, (int) (align / 8));
821 flags |= (align / 8) | SECTION_MERGE;
822 return get_section (name, flags, NULL);
824 return readonly_data_section;
827 /* Given NAME, a putative register name, discard any customary prefixes. */
829 static const char *
830 strip_reg_name (const char *name)
832 #ifdef REGISTER_PREFIX
833 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
834 name += strlen (REGISTER_PREFIX);
835 #endif
836 if (name[0] == '%' || name[0] == '#')
837 name++;
838 return name;
841 /* The user has asked for a DECL to have a particular name. Set (or
842 change) it in such a way that we don't prefix an underscore to
843 it. */
844 void
845 set_user_assembler_name (tree decl, const char *name)
847 char *starred = (char *) alloca (strlen (name) + 2);
848 starred[0] = '*';
849 strcpy (starred + 1, name);
850 change_decl_assembler_name (decl, get_identifier (starred));
851 SET_DECL_RTL (decl, NULL_RTX);
854 /* Decode an `asm' spec for a declaration as a register name.
855 Return the register number, or -1 if nothing specified,
856 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
857 or -3 if ASMSPEC is `cc' and is not recognized,
858 or -4 if ASMSPEC is `memory' and is not recognized.
859 Accept an exact spelling or a decimal number.
860 Prefixes such as % are optional. */
863 decode_reg_name_and_count (const char *asmspec, int *pnregs)
865 /* Presume just one register is clobbered. */
866 *pnregs = 1;
868 if (asmspec != 0)
870 int i;
872 /* Get rid of confusing prefixes. */
873 asmspec = strip_reg_name (asmspec);
875 /* Allow a decimal number as a "register name". */
876 for (i = strlen (asmspec) - 1; i >= 0; i--)
877 if (! ISDIGIT (asmspec[i]))
878 break;
879 if (asmspec[0] != 0 && i < 0)
881 i = atoi (asmspec);
882 if (i < FIRST_PSEUDO_REGISTER && i >= 0)
883 return i;
884 else
885 return -2;
888 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
889 if (reg_names[i][0]
890 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
891 return i;
893 #ifdef OVERLAPPING_REGISTER_NAMES
895 static const struct
897 const char *const name;
898 const int number;
899 const int nregs;
900 } table[] = OVERLAPPING_REGISTER_NAMES;
902 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
903 if (table[i].name[0]
904 && ! strcmp (asmspec, table[i].name))
906 *pnregs = table[i].nregs;
907 return table[i].number;
910 #endif /* OVERLAPPING_REGISTER_NAMES */
912 #ifdef ADDITIONAL_REGISTER_NAMES
914 static const struct { const char *const name; const int number; } table[]
915 = ADDITIONAL_REGISTER_NAMES;
917 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
918 if (table[i].name[0]
919 && ! strcmp (asmspec, table[i].name))
920 return table[i].number;
922 #endif /* ADDITIONAL_REGISTER_NAMES */
924 if (!strcmp (asmspec, "memory"))
925 return -4;
927 if (!strcmp (asmspec, "cc"))
928 return -3;
930 return -2;
933 return -1;
937 decode_reg_name (const char *name)
939 int count;
940 return decode_reg_name_and_count (name, &count);
944 /* Return true if DECL's initializer is suitable for a BSS section. */
946 bool
947 bss_initializer_p (const_tree decl)
949 return (DECL_INITIAL (decl) == NULL
950 || DECL_INITIAL (decl) == error_mark_node
951 || (flag_zero_initialized_in_bss
952 /* Leave constant zeroes in .rodata so they
953 can be shared. */
954 && !TREE_READONLY (decl)
955 && initializer_zerop (DECL_INITIAL (decl))));
958 /* Compute the alignment of variable specified by DECL.
959 DONT_OUTPUT_DATA is from assemble_variable. */
961 void
962 align_variable (tree decl, bool dont_output_data)
964 unsigned int align = DECL_ALIGN (decl);
966 /* In the case for initialing an array whose length isn't specified,
967 where we have not yet been able to do the layout,
968 figure out the proper alignment now. */
969 if (dont_output_data && DECL_SIZE (decl) == 0
970 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
971 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
973 /* Some object file formats have a maximum alignment which they support.
974 In particular, a.out format supports a maximum alignment of 4. */
975 if (align > MAX_OFILE_ALIGNMENT)
977 error ("alignment of %q+D is greater than maximum object "
978 "file alignment %d", decl,
979 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
980 align = MAX_OFILE_ALIGNMENT;
983 if (! DECL_USER_ALIGN (decl))
985 #ifdef DATA_ABI_ALIGNMENT
986 unsigned int data_abi_align
987 = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
988 /* For backwards compatibility, don't assume the ABI alignment for
989 TLS variables. */
990 if (! DECL_THREAD_LOCAL_P (decl) || data_abi_align <= BITS_PER_WORD)
991 align = data_abi_align;
992 #endif
994 /* On some machines, it is good to increase alignment sometimes.
995 But as DECL_ALIGN is used both for actually emitting the variable
996 and for code accessing the variable as guaranteed alignment, we
997 can only increase the alignment if it is a performance optimization
998 if the references to it must bind to the current definition. */
999 if (decl_binds_to_current_def_p (decl)
1000 && !DECL_VIRTUAL_P (decl))
1002 #ifdef DATA_ALIGNMENT
1003 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1004 /* Don't increase alignment too much for TLS variables - TLS space
1005 is too precious. */
1006 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1007 align = data_align;
1008 #endif
1009 #ifdef CONSTANT_ALIGNMENT
1010 if (DECL_INITIAL (decl) != 0
1011 && DECL_INITIAL (decl) != error_mark_node)
1013 unsigned int const_align
1014 = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
1015 /* Don't increase alignment too much for TLS variables - TLS
1016 space is too precious. */
1017 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1018 align = const_align;
1020 #endif
1024 /* Reset the alignment in case we have made it tighter, so we can benefit
1025 from it in get_pointer_alignment. */
1026 DECL_ALIGN (decl) = align;
1029 /* Return DECL_ALIGN (decl), possibly increased for optimization purposes
1030 beyond what align_variable returned. */
1032 static unsigned int
1033 get_variable_align (tree decl)
1035 unsigned int align = DECL_ALIGN (decl);
1037 /* For user aligned vars or static vars align_variable already did
1038 everything. */
1039 if (DECL_USER_ALIGN (decl) || !TREE_PUBLIC (decl))
1040 return align;
1042 #ifdef DATA_ABI_ALIGNMENT
1043 if (DECL_THREAD_LOCAL_P (decl))
1044 align = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1045 #endif
1047 /* For decls that bind to the current definition, align_variable
1048 did also everything, except for not assuming ABI required alignment
1049 of TLS variables. For other vars, increase the alignment here
1050 as an optimization. */
1051 if (!decl_binds_to_current_def_p (decl))
1053 /* On some machines, it is good to increase alignment sometimes. */
1054 #ifdef DATA_ALIGNMENT
1055 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1056 /* Don't increase alignment too much for TLS variables - TLS space
1057 is too precious. */
1058 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1059 align = data_align;
1060 #endif
1061 #ifdef CONSTANT_ALIGNMENT
1062 if (DECL_INITIAL (decl) != 0 && DECL_INITIAL (decl) != error_mark_node)
1064 unsigned int const_align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl),
1065 align);
1066 /* Don't increase alignment too much for TLS variables - TLS space
1067 is too precious. */
1068 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1069 align = const_align;
1071 #endif
1074 return align;
1077 /* Return the section into which the given VAR_DECL or CONST_DECL
1078 should be placed. PREFER_NOSWITCH_P is true if a noswitch
1079 section should be used wherever possible. */
1081 section *
1082 get_variable_section (tree decl, bool prefer_noswitch_p)
1084 addr_space_t as = ADDR_SPACE_GENERIC;
1085 int reloc;
1087 if (TREE_TYPE (decl) != error_mark_node)
1088 as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1090 if (DECL_COMMON (decl))
1092 /* If the decl has been given an explicit section name, or it resides
1093 in a non-generic address space, then it isn't common, and shouldn't
1094 be handled as such. */
1095 gcc_assert (DECL_SECTION_NAME (decl) == NULL
1096 && ADDR_SPACE_GENERIC_P (as));
1097 if (DECL_THREAD_LOCAL_P (decl))
1098 return tls_comm_section;
1099 else if (TREE_PUBLIC (decl) && bss_initializer_p (decl))
1100 return comm_section;
1103 if (DECL_INITIAL (decl) == error_mark_node)
1104 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1105 else if (DECL_INITIAL (decl))
1106 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1107 else
1108 reloc = 0;
1110 resolve_unique_section (decl, reloc, flag_data_sections);
1111 if (IN_NAMED_SECTION (decl))
1112 return get_named_section (decl, NULL, reloc);
1114 if (ADDR_SPACE_GENERIC_P (as)
1115 && !DECL_THREAD_LOCAL_P (decl)
1116 && !(prefer_noswitch_p && targetm.have_switchable_bss_sections)
1117 && bss_initializer_p (decl))
1119 if (!TREE_PUBLIC (decl)
1120 && !((flag_sanitize & SANITIZE_ADDRESS)
1121 && asan_protect_global (decl)))
1122 return lcomm_section;
1123 if (bss_noswitch_section)
1124 return bss_noswitch_section;
1127 return targetm.asm_out.select_section (decl, reloc,
1128 get_variable_align (decl));
1131 /* Return the block into which object_block DECL should be placed. */
1133 static struct object_block *
1134 get_block_for_decl (tree decl)
1136 section *sect;
1138 if (TREE_CODE (decl) == VAR_DECL)
1140 /* The object must be defined in this translation unit. */
1141 if (DECL_EXTERNAL (decl))
1142 return NULL;
1144 /* There's no point using object blocks for something that is
1145 isolated by definition. */
1146 if (DECL_COMDAT_GROUP (decl))
1147 return NULL;
1150 /* We can only calculate block offsets if the decl has a known
1151 constant size. */
1152 if (DECL_SIZE_UNIT (decl) == NULL)
1153 return NULL;
1154 if (!tree_fits_uhwi_p (DECL_SIZE_UNIT (decl)))
1155 return NULL;
1157 /* Find out which section should contain DECL. We cannot put it into
1158 an object block if it requires a standalone definition. */
1159 if (TREE_CODE (decl) == VAR_DECL)
1160 align_variable (decl, 0);
1161 sect = get_variable_section (decl, true);
1162 if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
1163 return NULL;
1165 return get_block_for_section (sect);
1168 /* Make sure block symbol SYMBOL is in block BLOCK. */
1170 static void
1171 change_symbol_block (rtx symbol, struct object_block *block)
1173 if (block != SYMBOL_REF_BLOCK (symbol))
1175 gcc_assert (SYMBOL_REF_BLOCK_OFFSET (symbol) < 0);
1176 SYMBOL_REF_BLOCK (symbol) = block;
1180 /* Return true if it is possible to put DECL in an object_block. */
1182 static bool
1183 use_blocks_for_decl_p (tree decl)
1185 /* Only data DECLs can be placed into object blocks. */
1186 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != CONST_DECL)
1187 return false;
1189 /* Detect decls created by dw2_force_const_mem. Such decls are
1190 special because DECL_INITIAL doesn't specify the decl's true value.
1191 dw2_output_indirect_constants will instead call assemble_variable
1192 with dont_output_data set to 1 and then print the contents itself. */
1193 if (DECL_INITIAL (decl) == decl)
1194 return false;
1196 /* If this decl is an alias, then we don't want to emit a
1197 definition. */
1198 if (lookup_attribute ("alias", DECL_ATTRIBUTES (decl)))
1199 return false;
1201 return targetm.use_blocks_for_decl_p (decl);
1204 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
1205 have static storage duration. In other words, it should not be an
1206 automatic variable, including PARM_DECLs.
1208 There is, however, one exception: this function handles variables
1209 explicitly placed in a particular register by the user.
1211 This is never called for PARM_DECL nodes. */
1213 void
1214 make_decl_rtl (tree decl)
1216 const char *name = 0;
1217 int reg_number;
1218 rtx x;
1220 /* Check that we are not being given an automatic variable. */
1221 gcc_assert (TREE_CODE (decl) != PARM_DECL
1222 && TREE_CODE (decl) != RESULT_DECL);
1224 /* A weak alias has TREE_PUBLIC set but not the other bits. */
1225 gcc_assert (TREE_CODE (decl) != VAR_DECL
1226 || TREE_STATIC (decl)
1227 || TREE_PUBLIC (decl)
1228 || DECL_EXTERNAL (decl)
1229 || DECL_REGISTER (decl));
1231 /* And that we were not given a type or a label. */
1232 gcc_assert (TREE_CODE (decl) != TYPE_DECL
1233 && TREE_CODE (decl) != LABEL_DECL);
1235 /* For a duplicate declaration, we can be called twice on the
1236 same DECL node. Don't discard the RTL already made. */
1237 if (DECL_RTL_SET_P (decl))
1239 /* If the old RTL had the wrong mode, fix the mode. */
1240 x = DECL_RTL (decl);
1241 if (GET_MODE (x) != DECL_MODE (decl))
1242 SET_DECL_RTL (decl, adjust_address_nv (x, DECL_MODE (decl), 0));
1244 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1245 return;
1247 /* ??? Another way to do this would be to maintain a hashed
1248 table of such critters. Instead of adding stuff to a DECL
1249 to give certain attributes to it, we could use an external
1250 hash map from DECL to set of attributes. */
1252 /* Let the target reassign the RTL if it wants.
1253 This is necessary, for example, when one machine specific
1254 decl attribute overrides another. */
1255 targetm.encode_section_info (decl, DECL_RTL (decl), false);
1257 /* If the symbol has a SYMBOL_REF_BLOCK field, update it based
1258 on the new decl information. */
1259 if (MEM_P (x)
1260 && GET_CODE (XEXP (x, 0)) == SYMBOL_REF
1261 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (x, 0)))
1262 change_symbol_block (XEXP (x, 0), get_block_for_decl (decl));
1264 return;
1267 /* If this variable belongs to the global constant pool, retrieve the
1268 pre-computed RTL or recompute it in LTO mode. */
1269 if (TREE_CODE (decl) == VAR_DECL && DECL_IN_CONSTANT_POOL (decl))
1271 SET_DECL_RTL (decl, output_constant_def (DECL_INITIAL (decl), 1));
1272 return;
1275 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
1277 if (name[0] != '*' && TREE_CODE (decl) != FUNCTION_DECL
1278 && DECL_REGISTER (decl))
1280 error ("register name not specified for %q+D", decl);
1282 else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1284 const char *asmspec = name+1;
1285 enum machine_mode mode = DECL_MODE (decl);
1286 reg_number = decode_reg_name (asmspec);
1287 /* First detect errors in declaring global registers. */
1288 if (reg_number == -1)
1289 error ("register name not specified for %q+D", decl);
1290 else if (reg_number < 0)
1291 error ("invalid register name for %q+D", decl);
1292 else if (mode == BLKmode)
1293 error ("data type of %q+D isn%'t suitable for a register",
1294 decl);
1295 else if (!in_hard_reg_set_p (accessible_reg_set, mode, reg_number))
1296 error ("the register specified for %q+D cannot be accessed"
1297 " by the current target", decl);
1298 else if (!in_hard_reg_set_p (operand_reg_set, mode, reg_number))
1299 error ("the register specified for %q+D is not general enough"
1300 " to be used as a register variable", decl);
1301 else if (!HARD_REGNO_MODE_OK (reg_number, mode))
1302 error ("register specified for %q+D isn%'t suitable for data type",
1303 decl);
1304 /* Now handle properly declared static register variables. */
1305 else
1307 int nregs;
1309 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
1311 DECL_INITIAL (decl) = 0;
1312 error ("global register variable has initial value");
1314 if (TREE_THIS_VOLATILE (decl))
1315 warning (OPT_Wvolatile_register_var,
1316 "optimization may eliminate reads and/or "
1317 "writes to register variables");
1319 /* If the user specified one of the eliminables registers here,
1320 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
1321 confused with that register and be eliminated. This usage is
1322 somewhat suspect... */
1324 SET_DECL_RTL (decl, gen_rtx_raw_REG (mode, reg_number));
1325 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
1326 REG_USERVAR_P (DECL_RTL (decl)) = 1;
1328 if (TREE_STATIC (decl))
1330 /* Make this register global, so not usable for anything
1331 else. */
1332 #ifdef ASM_DECLARE_REGISTER_GLOBAL
1333 name = IDENTIFIER_POINTER (DECL_NAME (decl));
1334 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
1335 #endif
1336 nregs = hard_regno_nregs[reg_number][mode];
1337 while (nregs > 0)
1338 globalize_reg (decl, reg_number + --nregs);
1341 /* As a register variable, it has no section. */
1342 return;
1345 /* Now handle ordinary static variables and functions (in memory).
1346 Also handle vars declared register invalidly. */
1347 else if (name[0] == '*')
1349 #ifdef REGISTER_PREFIX
1350 if (strlen (REGISTER_PREFIX) != 0)
1352 reg_number = decode_reg_name (name);
1353 if (reg_number >= 0 || reg_number == -3)
1354 error ("register name given for non-register variable %q+D", decl);
1356 #endif
1359 /* Specifying a section attribute on a variable forces it into a
1360 non-.bss section, and thus it cannot be common. */
1361 /* FIXME: In general this code should not be necessary because
1362 visibility pass is doing the same work. But notice_global_symbol
1363 is called early and it needs to make DECL_RTL to get the name.
1364 we take care of recomputing the DECL_RTL after visibility is changed. */
1365 if (TREE_CODE (decl) == VAR_DECL
1366 && DECL_SECTION_NAME (decl) != NULL_TREE
1367 && DECL_INITIAL (decl) == NULL_TREE
1368 && DECL_COMMON (decl))
1369 DECL_COMMON (decl) = 0;
1371 /* Variables can't be both common and weak. */
1372 if (TREE_CODE (decl) == VAR_DECL && DECL_WEAK (decl))
1373 DECL_COMMON (decl) = 0;
1375 if (use_object_blocks_p () && use_blocks_for_decl_p (decl))
1376 x = create_block_symbol (name, get_block_for_decl (decl), -1);
1377 else
1379 enum machine_mode address_mode = Pmode;
1380 if (TREE_TYPE (decl) != error_mark_node)
1382 addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1383 address_mode = targetm.addr_space.address_mode (as);
1385 x = gen_rtx_SYMBOL_REF (address_mode, name);
1387 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
1388 SET_SYMBOL_REF_DECL (x, decl);
1390 x = gen_rtx_MEM (DECL_MODE (decl), x);
1391 if (TREE_CODE (decl) != FUNCTION_DECL)
1392 set_mem_attributes (x, decl, 1);
1393 SET_DECL_RTL (decl, x);
1395 /* Optionally set flags or add text to the name to record information
1396 such as that it is a function name.
1397 If the name is changed, the macro ASM_OUTPUT_LABELREF
1398 will have to know how to strip this information. */
1399 targetm.encode_section_info (decl, DECL_RTL (decl), true);
1402 /* Like make_decl_rtl, but inhibit creation of new alias sets when
1403 calling make_decl_rtl. Also, reset DECL_RTL before returning the
1404 rtl. */
1407 make_decl_rtl_for_debug (tree decl)
1409 unsigned int save_aliasing_flag;
1410 rtx rtl;
1412 if (DECL_RTL_SET_P (decl))
1413 return DECL_RTL (decl);
1415 /* Kludge alert! Somewhere down the call chain, make_decl_rtl will
1416 call new_alias_set. If running with -fcompare-debug, sometimes
1417 we do not want to create alias sets that will throw the alias
1418 numbers off in the comparison dumps. So... clearing
1419 flag_strict_aliasing will keep new_alias_set() from creating a
1420 new set. */
1421 save_aliasing_flag = flag_strict_aliasing;
1422 flag_strict_aliasing = 0;
1424 rtl = DECL_RTL (decl);
1425 /* Reset DECL_RTL back, as various parts of the compiler expects
1426 DECL_RTL set meaning it is actually going to be output. */
1427 SET_DECL_RTL (decl, NULL);
1429 flag_strict_aliasing = save_aliasing_flag;
1430 return rtl;
1433 /* Output a string of literal assembler code
1434 for an `asm' keyword used between functions. */
1436 void
1437 assemble_asm (tree string)
1439 const char *p;
1440 app_enable ();
1442 if (TREE_CODE (string) == ADDR_EXPR)
1443 string = TREE_OPERAND (string, 0);
1445 p = TREE_STRING_POINTER (string);
1446 fprintf (asm_out_file, "%s%s\n", p[0] == '\t' ? "" : "\t", p);
1449 /* Write the address of the entity given by SYMBOL to SEC. */
1450 void
1451 assemble_addr_to_section (rtx symbol, section *sec)
1453 switch_to_section (sec);
1454 assemble_align (POINTER_SIZE);
1455 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1458 /* Return the numbered .ctors.N (if CONSTRUCTOR_P) or .dtors.N (if
1459 not) section for PRIORITY. */
1460 section *
1461 get_cdtor_priority_section (int priority, bool constructor_p)
1463 char buf[16];
1465 /* ??? This only works reliably with the GNU linker. */
1466 sprintf (buf, "%s.%.5u",
1467 constructor_p ? ".ctors" : ".dtors",
1468 /* Invert the numbering so the linker puts us in the proper
1469 order; constructors are run from right to left, and the
1470 linker sorts in increasing order. */
1471 MAX_INIT_PRIORITY - priority);
1472 return get_section (buf, SECTION_WRITE, NULL);
1475 void
1476 default_named_section_asm_out_destructor (rtx symbol, int priority)
1478 section *sec;
1480 if (priority != DEFAULT_INIT_PRIORITY)
1481 sec = get_cdtor_priority_section (priority,
1482 /*constructor_p=*/false);
1483 else
1484 sec = get_section (".dtors", SECTION_WRITE, NULL);
1486 assemble_addr_to_section (symbol, sec);
1489 #ifdef DTORS_SECTION_ASM_OP
1490 void
1491 default_dtor_section_asm_out_destructor (rtx symbol,
1492 int priority ATTRIBUTE_UNUSED)
1494 assemble_addr_to_section (symbol, dtors_section);
1496 #endif
1498 void
1499 default_named_section_asm_out_constructor (rtx symbol, int priority)
1501 section *sec;
1503 if (priority != DEFAULT_INIT_PRIORITY)
1504 sec = get_cdtor_priority_section (priority,
1505 /*constructor_p=*/true);
1506 else
1507 sec = get_section (".ctors", SECTION_WRITE, NULL);
1509 assemble_addr_to_section (symbol, sec);
1512 #ifdef CTORS_SECTION_ASM_OP
1513 void
1514 default_ctor_section_asm_out_constructor (rtx symbol,
1515 int priority ATTRIBUTE_UNUSED)
1517 assemble_addr_to_section (symbol, ctors_section);
1519 #endif
1521 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1522 a nonzero value if the constant pool should be output before the
1523 start of the function, or a zero value if the pool should output
1524 after the end of the function. The default is to put it before the
1525 start. */
1527 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1528 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1529 #endif
1531 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1532 to be output to assembler.
1533 Set first_global_object_name and weak_global_object_name as appropriate. */
1535 void
1536 notice_global_symbol (tree decl)
1538 const char **type = &first_global_object_name;
1540 if (first_global_object_name
1541 || !TREE_PUBLIC (decl)
1542 || DECL_EXTERNAL (decl)
1543 || !DECL_NAME (decl)
1544 || (TREE_CODE (decl) != FUNCTION_DECL
1545 && (TREE_CODE (decl) != VAR_DECL
1546 || (DECL_COMMON (decl)
1547 && (DECL_INITIAL (decl) == 0
1548 || DECL_INITIAL (decl) == error_mark_node))))
1549 || !MEM_P (DECL_RTL (decl)))
1550 return;
1552 /* We win when global object is found, but it is useful to know about weak
1553 symbol as well so we can produce nicer unique names. */
1554 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl) || flag_shlib)
1555 type = &weak_global_object_name;
1557 if (!*type)
1559 const char *p;
1560 const char *name;
1561 rtx decl_rtl = DECL_RTL (decl);
1563 p = targetm.strip_name_encoding (XSTR (XEXP (decl_rtl, 0), 0));
1564 name = ggc_strdup (p);
1566 *type = name;
1570 /* If not using flag_reorder_blocks_and_partition, decide early whether the
1571 current function goes into the cold section, so that targets can use
1572 current_function_section during RTL expansion. DECL describes the
1573 function. */
1575 void
1576 decide_function_section (tree decl)
1578 first_function_block_is_cold = false;
1580 if (flag_reorder_blocks_and_partition)
1581 /* We will decide in assemble_start_function. */
1582 return;
1584 if (DECL_SECTION_NAME (decl))
1586 struct cgraph_node *node = cgraph_get_node (current_function_decl);
1587 /* Calls to function_section rely on first_function_block_is_cold
1588 being accurate. */
1589 first_function_block_is_cold = (node
1590 && node->frequency
1591 == NODE_FREQUENCY_UNLIKELY_EXECUTED);
1594 in_cold_section_p = first_function_block_is_cold;
1597 /* Output assembler code for the constant pool of a function and associated
1598 with defining the name of the function. DECL describes the function.
1599 NAME is the function's name. For the constant pool, we use the current
1600 constant pool data. */
1602 void
1603 assemble_start_function (tree decl, const char *fnname)
1605 int align;
1606 char tmp_label[100];
1607 bool hot_label_written = false;
1609 if (flag_reorder_blocks_and_partition)
1611 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTB", const_labelno);
1612 crtl->subsections.hot_section_label = ggc_strdup (tmp_label);
1613 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDB", const_labelno);
1614 crtl->subsections.cold_section_label = ggc_strdup (tmp_label);
1615 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTE", const_labelno);
1616 crtl->subsections.hot_section_end_label = ggc_strdup (tmp_label);
1617 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDE", const_labelno);
1618 crtl->subsections.cold_section_end_label = ggc_strdup (tmp_label);
1619 const_labelno++;
1621 else
1623 crtl->subsections.hot_section_label = NULL;
1624 crtl->subsections.cold_section_label = NULL;
1625 crtl->subsections.hot_section_end_label = NULL;
1626 crtl->subsections.cold_section_end_label = NULL;
1629 /* The following code does not need preprocessing in the assembler. */
1631 app_disable ();
1633 if (CONSTANT_POOL_BEFORE_FUNCTION)
1634 output_constant_pool (fnname, decl);
1636 /* Make sure the not and cold text (code) sections are properly
1637 aligned. This is necessary here in the case where the function
1638 has both hot and cold sections, because we don't want to re-set
1639 the alignment when the section switch happens mid-function. */
1641 if (flag_reorder_blocks_and_partition)
1643 first_function_block_is_cold = false;
1645 switch_to_section (unlikely_text_section ());
1646 assemble_align (DECL_ALIGN (decl));
1647 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_label);
1649 /* When the function starts with a cold section, we need to explicitly
1650 align the hot section and write out the hot section label.
1651 But if the current function is a thunk, we do not have a CFG. */
1652 if (!cfun->is_thunk
1653 && BB_PARTITION (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) == BB_COLD_PARTITION)
1655 switch_to_section (text_section);
1656 assemble_align (DECL_ALIGN (decl));
1657 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1658 hot_label_written = true;
1659 first_function_block_is_cold = true;
1661 in_cold_section_p = first_function_block_is_cold;
1665 /* Switch to the correct text section for the start of the function. */
1667 switch_to_section (function_section (decl));
1668 if (flag_reorder_blocks_and_partition
1669 && !hot_label_written)
1670 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1672 /* Tell assembler to move to target machine's alignment for functions. */
1673 align = floor_log2 (DECL_ALIGN (decl) / BITS_PER_UNIT);
1674 if (align > 0)
1676 ASM_OUTPUT_ALIGN (asm_out_file, align);
1679 /* Handle a user-specified function alignment.
1680 Note that we still need to align to DECL_ALIGN, as above,
1681 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1682 if (! DECL_USER_ALIGN (decl)
1683 && align_functions_log > align
1684 && optimize_function_for_speed_p (cfun))
1686 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1687 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1688 align_functions_log, align_functions - 1);
1689 #else
1690 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1691 #endif
1694 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1695 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1696 #endif
1698 if (!DECL_IGNORED_P (decl))
1699 (*debug_hooks->begin_function) (decl);
1701 /* Make function name accessible from other files, if appropriate. */
1703 if (TREE_PUBLIC (decl))
1705 notice_global_symbol (decl);
1707 globalize_decl (decl);
1709 maybe_assemble_visibility (decl);
1712 if (DECL_PRESERVE_P (decl))
1713 targetm.asm_out.mark_decl_preserved (fnname);
1715 /* Do any machine/system dependent processing of the function name. */
1716 #ifdef ASM_DECLARE_FUNCTION_NAME
1717 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1718 #else
1719 /* Standard thing is just output label for the function. */
1720 ASM_OUTPUT_FUNCTION_LABEL (asm_out_file, fnname, current_function_decl);
1721 #endif /* ASM_DECLARE_FUNCTION_NAME */
1723 if (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (decl)))
1724 saw_no_split_stack = true;
1727 /* Output assembler code associated with defining the size of the
1728 function. DECL describes the function. NAME is the function's name. */
1730 void
1731 assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED)
1733 #ifdef ASM_DECLARE_FUNCTION_SIZE
1734 /* We could have switched section in the middle of the function. */
1735 if (flag_reorder_blocks_and_partition)
1736 switch_to_section (function_section (decl));
1737 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1738 #endif
1739 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1741 output_constant_pool (fnname, decl);
1742 switch_to_section (function_section (decl)); /* need to switch back */
1744 /* Output labels for end of hot/cold text sections (to be used by
1745 debug info.) */
1746 if (flag_reorder_blocks_and_partition)
1748 section *save_text_section;
1750 save_text_section = in_section;
1751 switch_to_section (unlikely_text_section ());
1752 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label);
1753 if (first_function_block_is_cold)
1754 switch_to_section (text_section);
1755 else
1756 switch_to_section (function_section (decl));
1757 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label);
1758 switch_to_section (save_text_section);
1762 /* Assemble code to leave SIZE bytes of zeros. */
1764 void
1765 assemble_zeros (unsigned HOST_WIDE_INT size)
1767 /* Do no output if -fsyntax-only. */
1768 if (flag_syntax_only)
1769 return;
1771 #ifdef ASM_NO_SKIP_IN_TEXT
1772 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1773 so we must output 0s explicitly in the text section. */
1774 if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0)
1776 unsigned HOST_WIDE_INT i;
1777 for (i = 0; i < size; i++)
1778 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1780 else
1781 #endif
1782 if (size > 0)
1783 ASM_OUTPUT_SKIP (asm_out_file, size);
1786 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1788 void
1789 assemble_align (int align)
1791 if (align > BITS_PER_UNIT)
1793 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1797 /* Assemble a string constant with the specified C string as contents. */
1799 void
1800 assemble_string (const char *p, int size)
1802 int pos = 0;
1803 int maximum = 2000;
1805 /* If the string is very long, split it up. */
1807 while (pos < size)
1809 int thissize = size - pos;
1810 if (thissize > maximum)
1811 thissize = maximum;
1813 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1815 pos += thissize;
1816 p += thissize;
1821 /* A noswitch_section_callback for lcomm_section. */
1823 static bool
1824 emit_local (tree decl ATTRIBUTE_UNUSED,
1825 const char *name ATTRIBUTE_UNUSED,
1826 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1827 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1829 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1830 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name,
1831 size, DECL_ALIGN (decl));
1832 return true;
1833 #elif defined ASM_OUTPUT_ALIGNED_LOCAL
1834 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, DECL_ALIGN (decl));
1835 return true;
1836 #else
1837 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1838 return false;
1839 #endif
1842 /* A noswitch_section_callback for bss_noswitch_section. */
1844 #if defined ASM_OUTPUT_ALIGNED_BSS
1845 static bool
1846 emit_bss (tree decl ATTRIBUTE_UNUSED,
1847 const char *name ATTRIBUTE_UNUSED,
1848 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1849 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1851 #if defined ASM_OUTPUT_ALIGNED_BSS
1852 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size,
1853 get_variable_align (decl));
1854 return true;
1855 #endif
1857 #endif
1859 /* A noswitch_section_callback for comm_section. */
1861 static bool
1862 emit_common (tree decl ATTRIBUTE_UNUSED,
1863 const char *name ATTRIBUTE_UNUSED,
1864 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1865 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1867 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1868 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name,
1869 size, get_variable_align (decl));
1870 return true;
1871 #elif defined ASM_OUTPUT_ALIGNED_COMMON
1872 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size,
1873 get_variable_align (decl));
1874 return true;
1875 #else
1876 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
1877 return false;
1878 #endif
1881 /* A noswitch_section_callback for tls_comm_section. */
1883 static bool
1884 emit_tls_common (tree decl ATTRIBUTE_UNUSED,
1885 const char *name ATTRIBUTE_UNUSED,
1886 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1887 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1889 #ifdef ASM_OUTPUT_TLS_COMMON
1890 ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size);
1891 return true;
1892 #else
1893 sorry ("thread-local COMMON data not implemented");
1894 return true;
1895 #endif
1898 /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT.
1899 NAME is the name of DECL's SYMBOL_REF. */
1901 static void
1902 assemble_noswitch_variable (tree decl, const char *name, section *sect,
1903 unsigned int align)
1905 unsigned HOST_WIDE_INT size, rounded;
1907 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
1908 rounded = size;
1910 if ((flag_sanitize & SANITIZE_ADDRESS) && asan_protect_global (decl))
1911 size += asan_red_zone_size (size);
1913 /* Don't allocate zero bytes of common,
1914 since that means "undefined external" in the linker. */
1915 if (size == 0)
1916 rounded = 1;
1918 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1919 so that each uninitialized object starts on such a boundary. */
1920 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
1921 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1922 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1924 if (!sect->noswitch.callback (decl, name, size, rounded)
1925 && (unsigned HOST_WIDE_INT) (align / BITS_PER_UNIT) > rounded)
1926 error ("requested alignment for %q+D is greater than "
1927 "implemented alignment of %wu", decl, rounded);
1930 /* A subroutine of assemble_variable. Output the label and contents of
1931 DECL, whose address is a SYMBOL_REF with name NAME. DONT_OUTPUT_DATA
1932 is as for assemble_variable. */
1934 static void
1935 assemble_variable_contents (tree decl, const char *name,
1936 bool dont_output_data)
1938 /* Do any machine/system dependent processing of the object. */
1939 #ifdef ASM_DECLARE_OBJECT_NAME
1940 last_assemble_variable_decl = decl;
1941 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
1942 #else
1943 /* Standard thing is just output label for the object. */
1944 ASM_OUTPUT_LABEL (asm_out_file, name);
1945 #endif /* ASM_DECLARE_OBJECT_NAME */
1947 if (!dont_output_data)
1949 if (DECL_INITIAL (decl)
1950 && DECL_INITIAL (decl) != error_mark_node
1951 && !initializer_zerop (DECL_INITIAL (decl)))
1952 /* Output the actual data. */
1953 output_constant (DECL_INITIAL (decl),
1954 tree_to_uhwi (DECL_SIZE_UNIT (decl)),
1955 get_variable_align (decl));
1956 else
1957 /* Leave space for it. */
1958 assemble_zeros (tree_to_uhwi (DECL_SIZE_UNIT (decl)));
1962 /* Assemble everything that is needed for a variable or function declaration.
1963 Not used for automatic variables, and not used for function definitions.
1964 Should not be called for variables of incomplete structure type.
1966 TOP_LEVEL is nonzero if this variable has file scope.
1967 AT_END is nonzero if this is the special handling, at end of compilation,
1968 to define things that have had only tentative definitions.
1969 DONT_OUTPUT_DATA if nonzero means don't actually output the
1970 initial value (that will be done by the caller). */
1972 void
1973 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
1974 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
1976 const char *name;
1977 rtx decl_rtl, symbol;
1978 section *sect;
1979 unsigned int align;
1980 bool asan_protected = false;
1982 /* This function is supposed to handle VARIABLES. Ensure we have one. */
1983 gcc_assert (TREE_CODE (decl) == VAR_DECL);
1985 /* Emulated TLS had better not get this far. */
1986 gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl));
1988 last_assemble_variable_decl = 0;
1990 /* Normally no need to say anything here for external references,
1991 since assemble_external is called by the language-specific code
1992 when a declaration is first seen. */
1994 if (DECL_EXTERNAL (decl))
1995 return;
1997 /* Do nothing for global register variables. */
1998 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
2000 TREE_ASM_WRITTEN (decl) = 1;
2001 return;
2004 /* If type was incomplete when the variable was declared,
2005 see if it is complete now. */
2007 if (DECL_SIZE (decl) == 0)
2008 layout_decl (decl, 0);
2010 /* Still incomplete => don't allocate it; treat the tentative defn
2011 (which is what it must have been) as an `extern' reference. */
2013 if (!dont_output_data && DECL_SIZE (decl) == 0)
2015 error ("storage size of %q+D isn%'t known", decl);
2016 TREE_ASM_WRITTEN (decl) = 1;
2017 return;
2020 /* The first declaration of a variable that comes through this function
2021 decides whether it is global (in C, has external linkage)
2022 or local (in C, has internal linkage). So do nothing more
2023 if this function has already run. */
2025 if (TREE_ASM_WRITTEN (decl))
2026 return;
2028 /* Make sure targetm.encode_section_info is invoked before we set
2029 ASM_WRITTEN. */
2030 decl_rtl = DECL_RTL (decl);
2032 TREE_ASM_WRITTEN (decl) = 1;
2034 /* Do no output if -fsyntax-only. */
2035 if (flag_syntax_only)
2036 return;
2038 if (! dont_output_data
2039 && ! valid_constant_size_p (DECL_SIZE_UNIT (decl)))
2041 error ("size of variable %q+D is too large", decl);
2042 return;
2045 gcc_assert (MEM_P (decl_rtl));
2046 gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF);
2047 symbol = XEXP (decl_rtl, 0);
2049 /* If this symbol belongs to the tree constant pool, output the constant
2050 if it hasn't already been written. */
2051 if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
2053 tree decl = SYMBOL_REF_DECL (symbol);
2054 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
2055 output_constant_def_contents (symbol);
2056 return;
2059 app_disable ();
2061 name = XSTR (symbol, 0);
2062 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
2063 notice_global_symbol (decl);
2065 /* Compute the alignment of this data. */
2067 align_variable (decl, dont_output_data);
2069 if ((flag_sanitize & SANITIZE_ADDRESS)
2070 && asan_protect_global (decl))
2072 asan_protected = true;
2073 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
2074 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
2077 set_mem_align (decl_rtl, DECL_ALIGN (decl));
2079 align = get_variable_align (decl);
2081 if (TREE_PUBLIC (decl))
2082 maybe_assemble_visibility (decl);
2084 if (DECL_PRESERVE_P (decl))
2085 targetm.asm_out.mark_decl_preserved (name);
2087 /* First make the assembler name(s) global if appropriate. */
2088 sect = get_variable_section (decl, false);
2089 if (TREE_PUBLIC (decl)
2090 && (sect->common.flags & SECTION_COMMON) == 0)
2091 globalize_decl (decl);
2093 /* Output any data that we will need to use the address of. */
2094 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
2095 output_addressed_constants (DECL_INITIAL (decl));
2097 /* dbxout.c needs to know this. */
2098 if (sect && (sect->common.flags & SECTION_CODE) != 0)
2099 DECL_IN_TEXT_SECTION (decl) = 1;
2101 /* If the decl is part of an object_block, make sure that the decl
2102 has been positioned within its block, but do not write out its
2103 definition yet. output_object_blocks will do that later. */
2104 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
2106 gcc_assert (!dont_output_data);
2107 place_block_symbol (symbol);
2109 else if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
2110 assemble_noswitch_variable (decl, name, sect, align);
2111 else
2113 /* The following bit of code ensures that vtable_map
2114 variables are not only in the comdat section, but that
2115 each variable has its own unique comdat name. If this
2116 code is removed, the variables end up in the same section
2117 with a single comdat name.
2119 FIXME: resolve_unique_section needs to deal better with
2120 decls with both DECL_SECTION_NAME and DECL_ONE_ONLY. Once
2121 that is fixed, this if-else statement can be replaced with
2122 a single call to "switch_to_section (sect)". */
2123 if (sect->named.name
2124 && (strcmp (sect->named.name, ".vtable_map_vars") == 0))
2126 #if defined (OBJECT_FORMAT_ELF)
2127 targetm.asm_out.named_section (sect->named.name,
2128 sect->named.common.flags
2129 | SECTION_LINKONCE,
2130 DECL_NAME (decl));
2131 in_section = sect;
2132 #else
2133 switch_to_section (sect);
2134 #endif
2136 else
2137 switch_to_section (sect);
2138 if (align > BITS_PER_UNIT)
2139 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2140 assemble_variable_contents (decl, name, dont_output_data);
2141 if (asan_protected)
2143 unsigned HOST_WIDE_INT int size
2144 = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2145 assemble_zeros (asan_red_zone_size (size));
2151 /* Given a function declaration (FN_DECL), this function assembles the
2152 function into the .preinit_array section. */
2154 void
2155 assemble_vtv_preinit_initializer (tree fn_decl)
2157 section *sect;
2158 unsigned flags = SECTION_WRITE;
2159 rtx symbol = XEXP (DECL_RTL (fn_decl), 0);
2161 flags |= SECTION_NOTYPE;
2162 sect = get_section (".preinit_array", flags, fn_decl);
2163 switch_to_section (sect);
2164 assemble_addr_to_section (symbol, sect);
2167 /* Return 1 if type TYPE contains any pointers. */
2169 static int
2170 contains_pointers_p (tree type)
2172 switch (TREE_CODE (type))
2174 case POINTER_TYPE:
2175 case REFERENCE_TYPE:
2176 /* I'm not sure whether OFFSET_TYPE needs this treatment,
2177 so I'll play safe and return 1. */
2178 case OFFSET_TYPE:
2179 return 1;
2181 case RECORD_TYPE:
2182 case UNION_TYPE:
2183 case QUAL_UNION_TYPE:
2185 tree fields;
2186 /* For a type that has fields, see if the fields have pointers. */
2187 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2188 if (TREE_CODE (fields) == FIELD_DECL
2189 && contains_pointers_p (TREE_TYPE (fields)))
2190 return 1;
2191 return 0;
2194 case ARRAY_TYPE:
2195 /* An array type contains pointers if its element type does. */
2196 return contains_pointers_p (TREE_TYPE (type));
2198 default:
2199 return 0;
2203 /* We delay assemble_external processing until
2204 the compilation unit is finalized. This is the best we can do for
2205 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2206 it all the way to final. See PR 17982 for further discussion. */
2207 static GTY(()) tree pending_assemble_externals;
2209 #ifdef ASM_OUTPUT_EXTERNAL
2210 /* Some targets delay some output to final using TARGET_ASM_FILE_END.
2211 As a result, assemble_external can be called after the list of externals
2212 is processed and the pointer set destroyed. */
2213 static bool pending_assemble_externals_processed;
2215 /* Avoid O(external_decls**2) lookups in the pending_assemble_externals
2216 TREE_LIST in assemble_external. */
2217 static struct pointer_set_t *pending_assemble_externals_set;
2219 /* True if DECL is a function decl for which no out-of-line copy exists.
2220 It is assumed that DECL's assembler name has been set. */
2222 static bool
2223 incorporeal_function_p (tree decl)
2225 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
2227 const char *name;
2229 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2230 && (DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA
2231 || DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA_WITH_ALIGN))
2232 return true;
2234 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2235 /* Atomic or sync builtins which have survived this far will be
2236 resolved externally and therefore are not incorporeal. */
2237 if (strncmp (name, "__builtin_", 10) == 0)
2238 return true;
2240 return false;
2243 /* Actually do the tests to determine if this is necessary, and invoke
2244 ASM_OUTPUT_EXTERNAL. */
2245 static void
2246 assemble_external_real (tree decl)
2248 rtx rtl = DECL_RTL (decl);
2250 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2251 && !SYMBOL_REF_USED (XEXP (rtl, 0))
2252 && !incorporeal_function_p (decl))
2254 /* Some systems do require some output. */
2255 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2256 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2259 #endif
2261 void
2262 process_pending_assemble_externals (void)
2264 #ifdef ASM_OUTPUT_EXTERNAL
2265 tree list;
2266 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2267 assemble_external_real (TREE_VALUE (list));
2269 pending_assemble_externals = 0;
2270 pending_assemble_externals_processed = true;
2271 pointer_set_destroy (pending_assemble_externals_set);
2272 #endif
2275 /* This TREE_LIST contains any weak symbol declarations waiting
2276 to be emitted. */
2277 static GTY(()) tree weak_decls;
2279 /* Output something to declare an external symbol to the assembler,
2280 and qualifiers such as weakness. (Most assemblers don't need
2281 extern declaration, so we normally output nothing.) Do nothing if
2282 DECL is not external. */
2284 void
2285 assemble_external (tree decl ATTRIBUTE_UNUSED)
2287 /* Make sure that the ASM_OUT_FILE is open.
2288 If it's not, we should not be calling this function. */
2289 gcc_assert (asm_out_file);
2291 /* In a perfect world, the following condition would be true.
2292 Sadly, the Java and Go front ends emit assembly *from the front end*,
2293 bypassing the call graph. See PR52739. Fix before GCC 4.8. */
2294 #if 0
2295 /* This function should only be called if we are expanding, or have
2296 expanded, to RTL.
2297 Ideally, only final.c would be calling this function, but it is
2298 not clear whether that would break things somehow. See PR 17982
2299 for further discussion. */
2300 gcc_assert (cgraph_state == CGRAPH_STATE_EXPANSION
2301 || cgraph_state == CGRAPH_STATE_FINISHED);
2302 #endif
2304 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2305 return;
2307 /* We want to output annotation for weak and external symbols at
2308 very last to check if they are references or not. */
2310 if (TARGET_SUPPORTS_WEAK
2311 && DECL_WEAK (decl)
2312 /* TREE_STATIC is a weird and abused creature which is not
2313 generally the right test for whether an entity has been
2314 locally emitted, inlined or otherwise not-really-extern, but
2315 for declarations that can be weak, it happens to be
2316 match. */
2317 && !TREE_STATIC (decl)
2318 && lookup_attribute ("weak", DECL_ATTRIBUTES (decl))
2319 && value_member (decl, weak_decls) == NULL_TREE)
2320 weak_decls = tree_cons (NULL, decl, weak_decls);
2322 #ifdef ASM_OUTPUT_EXTERNAL
2323 if (pending_assemble_externals_processed)
2325 assemble_external_real (decl);
2326 return;
2329 if (! pointer_set_insert (pending_assemble_externals_set, decl))
2330 pending_assemble_externals = tree_cons (NULL, decl,
2331 pending_assemble_externals);
2332 #endif
2335 /* Similar, for calling a library function FUN. */
2337 void
2338 assemble_external_libcall (rtx fun)
2340 /* Declare library function name external when first used, if nec. */
2341 if (! SYMBOL_REF_USED (fun))
2343 SYMBOL_REF_USED (fun) = 1;
2344 targetm.asm_out.external_libcall (fun);
2348 /* Assemble a label named NAME. */
2350 void
2351 assemble_label (FILE *file, const char *name)
2353 ASM_OUTPUT_LABEL (file, name);
2356 /* Set the symbol_referenced flag for ID. */
2357 void
2358 mark_referenced (tree id)
2360 TREE_SYMBOL_REFERENCED (id) = 1;
2363 /* Set the symbol_referenced flag for DECL and notify callgraph. */
2364 void
2365 mark_decl_referenced (tree decl)
2367 if (TREE_CODE (decl) == FUNCTION_DECL)
2369 /* Extern inline functions don't become needed when referenced.
2370 If we know a method will be emitted in other TU and no new
2371 functions can be marked reachable, just use the external
2372 definition. */
2373 struct cgraph_node *node = cgraph_get_create_node (decl);
2374 if (!DECL_EXTERNAL (decl)
2375 && !node->definition)
2376 cgraph_mark_force_output_node (node);
2378 else if (TREE_CODE (decl) == VAR_DECL)
2380 varpool_node *node = varpool_node_for_decl (decl);
2381 /* C++ frontend use mark_decl_references to force COMDAT variables
2382 to be output that might appear dead otherwise. */
2383 node->force_output = true;
2385 /* else do nothing - we can get various sorts of CST nodes here,
2386 which do not need to be marked. */
2390 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS
2391 until we find an identifier that is not itself a transparent alias.
2392 Modify the alias passed to it by reference (and all aliases on the
2393 way to the ultimate target), such that they do not have to be
2394 followed again, and return the ultimate target of the alias
2395 chain. */
2397 static inline tree
2398 ultimate_transparent_alias_target (tree *alias)
2400 tree target = *alias;
2402 if (IDENTIFIER_TRANSPARENT_ALIAS (target))
2404 gcc_assert (TREE_CHAIN (target));
2405 target = ultimate_transparent_alias_target (&TREE_CHAIN (target));
2406 gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target)
2407 && ! TREE_CHAIN (target));
2408 *alias = target;
2411 return target;
2414 /* Output to FILE (an assembly file) a reference to NAME. If NAME
2415 starts with a *, the rest of NAME is output verbatim. Otherwise
2416 NAME is transformed in a target-specific way (usually by the
2417 addition of an underscore). */
2419 void
2420 assemble_name_raw (FILE *file, const char *name)
2422 if (name[0] == '*')
2423 fputs (&name[1], file);
2424 else
2425 ASM_OUTPUT_LABELREF (file, name);
2428 /* Like assemble_name_raw, but should be used when NAME might refer to
2429 an entity that is also represented as a tree (like a function or
2430 variable). If NAME does refer to such an entity, that entity will
2431 be marked as referenced. */
2433 void
2434 assemble_name (FILE *file, const char *name)
2436 const char *real_name;
2437 tree id;
2439 real_name = targetm.strip_name_encoding (name);
2441 id = maybe_get_identifier (real_name);
2442 if (id)
2444 tree id_orig = id;
2446 mark_referenced (id);
2447 ultimate_transparent_alias_target (&id);
2448 if (id != id_orig)
2449 name = IDENTIFIER_POINTER (id);
2450 gcc_assert (! TREE_CHAIN (id));
2453 assemble_name_raw (file, name);
2456 /* Allocate SIZE bytes writable static space with a gensym name
2457 and return an RTX to refer to its address. */
2460 assemble_static_space (unsigned HOST_WIDE_INT size)
2462 char name[12];
2463 const char *namestring;
2464 rtx x;
2466 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2467 ++const_labelno;
2468 namestring = ggc_strdup (name);
2470 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2471 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2473 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2474 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2475 BIGGEST_ALIGNMENT);
2476 #else
2477 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2478 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2479 #else
2481 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2482 so that each uninitialized object starts on such a boundary. */
2483 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2484 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2485 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2486 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2487 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2488 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2490 #endif
2491 #endif
2492 return x;
2495 /* Assemble the static constant template for function entry trampolines.
2496 This is done at most once per compilation.
2497 Returns an RTX for the address of the template. */
2499 static GTY(()) rtx initial_trampoline;
2502 assemble_trampoline_template (void)
2504 char label[256];
2505 const char *name;
2506 int align;
2507 rtx symbol;
2509 gcc_assert (targetm.asm_out.trampoline_template != NULL);
2511 if (initial_trampoline)
2512 return initial_trampoline;
2514 /* By default, put trampoline templates in read-only data section. */
2516 #ifdef TRAMPOLINE_SECTION
2517 switch_to_section (TRAMPOLINE_SECTION);
2518 #else
2519 switch_to_section (readonly_data_section);
2520 #endif
2522 /* Write the assembler code to define one. */
2523 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2524 if (align > 0)
2525 ASM_OUTPUT_ALIGN (asm_out_file, align);
2527 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2528 targetm.asm_out.trampoline_template (asm_out_file);
2530 /* Record the rtl to refer to it. */
2531 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2532 name = ggc_strdup (label);
2533 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2534 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2536 initial_trampoline = gen_const_mem (BLKmode, symbol);
2537 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2538 set_mem_size (initial_trampoline, TRAMPOLINE_SIZE);
2540 return initial_trampoline;
2543 /* A and B are either alignments or offsets. Return the minimum alignment
2544 that may be assumed after adding the two together. */
2546 static inline unsigned
2547 min_align (unsigned int a, unsigned int b)
2549 return (a | b) & -(a | b);
2552 /* Return the assembler directive for creating a given kind of integer
2553 object. SIZE is the number of bytes in the object and ALIGNED_P
2554 indicates whether it is known to be aligned. Return NULL if the
2555 assembly dialect has no such directive.
2557 The returned string should be printed at the start of a new line and
2558 be followed immediately by the object's initial value. */
2560 const char *
2561 integer_asm_op (int size, int aligned_p)
2563 struct asm_int_op *ops;
2565 if (aligned_p)
2566 ops = &targetm.asm_out.aligned_op;
2567 else
2568 ops = &targetm.asm_out.unaligned_op;
2570 switch (size)
2572 case 1:
2573 return targetm.asm_out.byte_op;
2574 case 2:
2575 return ops->hi;
2576 case 4:
2577 return ops->si;
2578 case 8:
2579 return ops->di;
2580 case 16:
2581 return ops->ti;
2582 default:
2583 return NULL;
2587 /* Use directive OP to assemble an integer object X. Print OP at the
2588 start of the line, followed immediately by the value of X. */
2590 void
2591 assemble_integer_with_op (const char *op, rtx x)
2593 fputs (op, asm_out_file);
2594 output_addr_const (asm_out_file, x);
2595 fputc ('\n', asm_out_file);
2598 /* The default implementation of the asm_out.integer target hook. */
2600 bool
2601 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2602 unsigned int size ATTRIBUTE_UNUSED,
2603 int aligned_p ATTRIBUTE_UNUSED)
2605 const char *op = integer_asm_op (size, aligned_p);
2606 /* Avoid GAS bugs for large values. Specifically negative values whose
2607 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2608 if (size > UNITS_PER_WORD && size > POINTER_SIZE / BITS_PER_UNIT)
2609 return false;
2610 return op && (assemble_integer_with_op (op, x), true);
2613 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2614 the alignment of the integer in bits. Return 1 if we were able to output
2615 the constant, otherwise 0. We must be able to output the constant,
2616 if FORCE is nonzero. */
2618 bool
2619 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2621 int aligned_p;
2623 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2625 /* See if the target hook can handle this kind of object. */
2626 if (targetm.asm_out.integer (x, size, aligned_p))
2627 return true;
2629 /* If the object is a multi-byte one, try splitting it up. Split
2630 it into words it if is multi-word, otherwise split it into bytes. */
2631 if (size > 1)
2633 enum machine_mode omode, imode;
2634 unsigned int subalign;
2635 unsigned int subsize, i;
2636 enum mode_class mclass;
2638 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2639 subalign = MIN (align, subsize * BITS_PER_UNIT);
2640 if (GET_CODE (x) == CONST_FIXED)
2641 mclass = GET_MODE_CLASS (GET_MODE (x));
2642 else
2643 mclass = MODE_INT;
2645 omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0);
2646 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0);
2648 for (i = 0; i < size; i += subsize)
2650 rtx partial = simplify_subreg (omode, x, imode, i);
2651 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2652 break;
2654 if (i == size)
2655 return true;
2657 /* If we've printed some of it, but not all of it, there's no going
2658 back now. */
2659 gcc_assert (!i);
2662 gcc_assert (!force);
2664 return false;
2667 void
2668 assemble_real (REAL_VALUE_TYPE d, enum machine_mode mode, unsigned int align)
2670 long data[4] = {0, 0, 0, 0};
2671 int i;
2672 int bitsize, nelts, nunits, units_per;
2674 /* This is hairy. We have a quantity of known size. real_to_target
2675 will put it into an array of *host* longs, 32 bits per element
2676 (even if long is more than 32 bits). We need to determine the
2677 number of array elements that are occupied (nelts) and the number
2678 of *target* min-addressable units that will be occupied in the
2679 object file (nunits). We cannot assume that 32 divides the
2680 mode's bitsize (size * BITS_PER_UNIT) evenly.
2682 size * BITS_PER_UNIT is used here to make sure that padding bits
2683 (which might appear at either end of the value; real_to_target
2684 will include the padding bits in its output array) are included. */
2686 nunits = GET_MODE_SIZE (mode);
2687 bitsize = nunits * BITS_PER_UNIT;
2688 nelts = CEIL (bitsize, 32);
2689 units_per = 32 / BITS_PER_UNIT;
2691 real_to_target (data, &d, mode);
2693 /* Put out the first word with the specified alignment. */
2694 assemble_integer (GEN_INT (data[0]), MIN (nunits, units_per), align, 1);
2695 nunits -= units_per;
2697 /* Subsequent words need only 32-bit alignment. */
2698 align = min_align (align, 32);
2700 for (i = 1; i < nelts; i++)
2702 assemble_integer (GEN_INT (data[i]), MIN (nunits, units_per), align, 1);
2703 nunits -= units_per;
2707 /* Given an expression EXP with a constant value,
2708 reduce it to the sum of an assembler symbol and an integer.
2709 Store them both in the structure *VALUE.
2710 EXP must be reducible. */
2712 struct addr_const {
2713 rtx base;
2714 HOST_WIDE_INT offset;
2717 static void
2718 decode_addr_const (tree exp, struct addr_const *value)
2720 tree target = TREE_OPERAND (exp, 0);
2721 int offset = 0;
2722 rtx x;
2724 while (1)
2726 if (TREE_CODE (target) == COMPONENT_REF
2727 && tree_fits_shwi_p (byte_position (TREE_OPERAND (target, 1))))
2729 offset += int_byte_position (TREE_OPERAND (target, 1));
2730 target = TREE_OPERAND (target, 0);
2732 else if (TREE_CODE (target) == ARRAY_REF
2733 || TREE_CODE (target) == ARRAY_RANGE_REF)
2735 offset += (tree_to_uhwi (TYPE_SIZE_UNIT (TREE_TYPE (target)))
2736 * tree_to_shwi (TREE_OPERAND (target, 1)));
2737 target = TREE_OPERAND (target, 0);
2739 else if (TREE_CODE (target) == MEM_REF
2740 && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR)
2742 offset += mem_ref_offset (target).to_short_addr ();
2743 target = TREE_OPERAND (TREE_OPERAND (target, 0), 0);
2745 else if (TREE_CODE (target) == INDIRECT_REF
2746 && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR
2747 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0))
2748 == ADDR_EXPR)
2749 target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0);
2750 else
2751 break;
2754 switch (TREE_CODE (target))
2756 case VAR_DECL:
2757 case FUNCTION_DECL:
2758 x = DECL_RTL (target);
2759 break;
2761 case LABEL_DECL:
2762 x = gen_rtx_MEM (FUNCTION_MODE,
2763 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2764 break;
2766 case REAL_CST:
2767 case FIXED_CST:
2768 case STRING_CST:
2769 case COMPLEX_CST:
2770 case CONSTRUCTOR:
2771 case INTEGER_CST:
2772 x = output_constant_def (target, 1);
2773 break;
2775 default:
2776 gcc_unreachable ();
2779 gcc_assert (MEM_P (x));
2780 x = XEXP (x, 0);
2782 value->base = x;
2783 value->offset = offset;
2787 static GTY((param_is (struct constant_descriptor_tree)))
2788 htab_t const_desc_htab;
2790 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2792 /* Constant pool accessor function. */
2794 htab_t
2795 constant_pool_htab (void)
2797 return const_desc_htab;
2800 /* Compute a hash code for a constant expression. */
2802 static hashval_t
2803 const_desc_hash (const void *ptr)
2805 return ((const struct constant_descriptor_tree *)ptr)->hash;
2808 static hashval_t
2809 const_hash_1 (const tree exp)
2811 const char *p;
2812 hashval_t hi;
2813 int len, i;
2814 enum tree_code code = TREE_CODE (exp);
2816 /* Either set P and LEN to the address and len of something to hash and
2817 exit the switch or return a value. */
2819 switch (code)
2821 case INTEGER_CST:
2822 p = (char *) &TREE_INT_CST_ELT (exp, 0);
2823 len = TREE_INT_CST_NUNITS (exp) * sizeof (HOST_WIDE_INT);
2824 break;
2826 case REAL_CST:
2827 return real_hash (TREE_REAL_CST_PTR (exp));
2829 case FIXED_CST:
2830 return fixed_hash (TREE_FIXED_CST_PTR (exp));
2832 case STRING_CST:
2833 p = TREE_STRING_POINTER (exp);
2834 len = TREE_STRING_LENGTH (exp);
2835 break;
2837 case COMPLEX_CST:
2838 return (const_hash_1 (TREE_REALPART (exp)) * 5
2839 + const_hash_1 (TREE_IMAGPART (exp)));
2841 case VECTOR_CST:
2843 unsigned i;
2845 hi = 7 + VECTOR_CST_NELTS (exp);
2847 for (i = 0; i < VECTOR_CST_NELTS (exp); ++i)
2848 hi = hi * 563 + const_hash_1 (VECTOR_CST_ELT (exp, i));
2850 return hi;
2853 case CONSTRUCTOR:
2855 unsigned HOST_WIDE_INT idx;
2856 tree value;
2858 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2860 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
2861 if (value)
2862 hi = hi * 603 + const_hash_1 (value);
2864 return hi;
2867 case ADDR_EXPR:
2868 case FDESC_EXPR:
2870 struct addr_const value;
2872 decode_addr_const (exp, &value);
2873 switch (GET_CODE (value.base))
2875 case SYMBOL_REF:
2876 /* Don't hash the address of the SYMBOL_REF;
2877 only use the offset and the symbol name. */
2878 hi = value.offset;
2879 p = XSTR (value.base, 0);
2880 for (i = 0; p[i] != 0; i++)
2881 hi = ((hi * 613) + (unsigned) (p[i]));
2882 break;
2884 case LABEL_REF:
2885 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13;
2886 break;
2888 default:
2889 gcc_unreachable ();
2892 return hi;
2894 case PLUS_EXPR:
2895 case POINTER_PLUS_EXPR:
2896 case MINUS_EXPR:
2897 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2898 + const_hash_1 (TREE_OPERAND (exp, 1)));
2900 CASE_CONVERT:
2901 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
2903 default:
2904 /* A language specific constant. Just hash the code. */
2905 return code;
2908 /* Compute hashing function. */
2909 hi = len;
2910 for (i = 0; i < len; i++)
2911 hi = ((hi * 613) + (unsigned) (p[i]));
2913 return hi;
2916 /* Wrapper of compare_constant, for the htab interface. */
2917 static int
2918 const_desc_eq (const void *p1, const void *p2)
2920 const struct constant_descriptor_tree *const c1
2921 = (const struct constant_descriptor_tree *) p1;
2922 const struct constant_descriptor_tree *const c2
2923 = (const struct constant_descriptor_tree *) p2;
2924 if (c1->hash != c2->hash)
2925 return 0;
2926 return compare_constant (c1->value, c2->value);
2929 /* Compare t1 and t2, and return 1 only if they are known to result in
2930 the same bit pattern on output. */
2932 static int
2933 compare_constant (const tree t1, const tree t2)
2935 enum tree_code typecode;
2937 if (t1 == NULL_TREE)
2938 return t2 == NULL_TREE;
2939 if (t2 == NULL_TREE)
2940 return 0;
2942 if (TREE_CODE (t1) != TREE_CODE (t2))
2943 return 0;
2945 switch (TREE_CODE (t1))
2947 case INTEGER_CST:
2948 /* Integer constants are the same only if the same width of type. */
2949 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2950 return 0;
2951 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2952 return 0;
2953 return tree_int_cst_equal (t1, t2);
2955 case REAL_CST:
2956 /* Real constants are the same only if the same width of type. */
2957 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2958 return 0;
2960 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
2962 case FIXED_CST:
2963 /* Fixed constants are the same only if the same width of type. */
2964 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2965 return 0;
2967 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
2969 case STRING_CST:
2970 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2971 return 0;
2973 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
2974 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
2975 TREE_STRING_LENGTH (t1)));
2977 case COMPLEX_CST:
2978 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
2979 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
2981 case VECTOR_CST:
2983 unsigned i;
2985 if (VECTOR_CST_NELTS (t1) != VECTOR_CST_NELTS (t2))
2986 return 0;
2988 for (i = 0; i < VECTOR_CST_NELTS (t1); ++i)
2989 if (!compare_constant (VECTOR_CST_ELT (t1, i),
2990 VECTOR_CST_ELT (t2, i)))
2991 return 0;
2993 return 1;
2996 case CONSTRUCTOR:
2998 vec<constructor_elt, va_gc> *v1, *v2;
2999 unsigned HOST_WIDE_INT idx;
3001 typecode = TREE_CODE (TREE_TYPE (t1));
3002 if (typecode != TREE_CODE (TREE_TYPE (t2)))
3003 return 0;
3005 if (typecode == ARRAY_TYPE)
3007 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
3008 /* For arrays, check that the sizes all match. */
3009 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
3010 || size_1 == -1
3011 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
3012 return 0;
3014 else
3016 /* For record and union constructors, require exact type
3017 equality. */
3018 if (TREE_TYPE (t1) != TREE_TYPE (t2))
3019 return 0;
3022 v1 = CONSTRUCTOR_ELTS (t1);
3023 v2 = CONSTRUCTOR_ELTS (t2);
3024 if (vec_safe_length (v1) != vec_safe_length (v2))
3025 return 0;
3027 for (idx = 0; idx < vec_safe_length (v1); ++idx)
3029 constructor_elt *c1 = &(*v1)[idx];
3030 constructor_elt *c2 = &(*v2)[idx];
3032 /* Check that each value is the same... */
3033 if (!compare_constant (c1->value, c2->value))
3034 return 0;
3035 /* ... and that they apply to the same fields! */
3036 if (typecode == ARRAY_TYPE)
3038 if (!compare_constant (c1->index, c2->index))
3039 return 0;
3041 else
3043 if (c1->index != c2->index)
3044 return 0;
3048 return 1;
3051 case ADDR_EXPR:
3052 case FDESC_EXPR:
3054 struct addr_const value1, value2;
3055 enum rtx_code code;
3056 int ret;
3058 decode_addr_const (t1, &value1);
3059 decode_addr_const (t2, &value2);
3061 if (value1.offset != value2.offset)
3062 return 0;
3064 code = GET_CODE (value1.base);
3065 if (code != GET_CODE (value2.base))
3066 return 0;
3068 switch (code)
3070 case SYMBOL_REF:
3071 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3072 break;
3074 case LABEL_REF:
3075 ret = (CODE_LABEL_NUMBER (XEXP (value1.base, 0))
3076 == CODE_LABEL_NUMBER (XEXP (value2.base, 0)));
3077 break;
3079 default:
3080 gcc_unreachable ();
3082 return ret;
3085 case PLUS_EXPR:
3086 case POINTER_PLUS_EXPR:
3087 case MINUS_EXPR:
3088 case RANGE_EXPR:
3089 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3090 && compare_constant (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3092 CASE_CONVERT:
3093 case VIEW_CONVERT_EXPR:
3094 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3096 default:
3097 return 0;
3100 gcc_unreachable ();
3103 /* Make a copy of the whole tree structure for a constant. This
3104 handles the same types of nodes that compare_constant handles. */
3106 static tree
3107 copy_constant (tree exp)
3109 switch (TREE_CODE (exp))
3111 case ADDR_EXPR:
3112 /* For ADDR_EXPR, we do not want to copy the decl whose address
3113 is requested. We do want to copy constants though. */
3114 if (CONSTANT_CLASS_P (TREE_OPERAND (exp, 0)))
3115 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
3116 copy_constant (TREE_OPERAND (exp, 0)));
3117 else
3118 return copy_node (exp);
3120 case INTEGER_CST:
3121 case REAL_CST:
3122 case FIXED_CST:
3123 case STRING_CST:
3124 return copy_node (exp);
3126 case COMPLEX_CST:
3127 return build_complex (TREE_TYPE (exp),
3128 copy_constant (TREE_REALPART (exp)),
3129 copy_constant (TREE_IMAGPART (exp)));
3131 case PLUS_EXPR:
3132 case POINTER_PLUS_EXPR:
3133 case MINUS_EXPR:
3134 return build2 (TREE_CODE (exp), TREE_TYPE (exp),
3135 copy_constant (TREE_OPERAND (exp, 0)),
3136 copy_constant (TREE_OPERAND (exp, 1)));
3138 CASE_CONVERT:
3139 case VIEW_CONVERT_EXPR:
3140 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
3141 copy_constant (TREE_OPERAND (exp, 0)));
3143 case VECTOR_CST:
3144 return build_vector (TREE_TYPE (exp), VECTOR_CST_ELTS (exp));
3146 case CONSTRUCTOR:
3148 tree copy = copy_node (exp);
3149 vec<constructor_elt, va_gc> *v;
3150 unsigned HOST_WIDE_INT idx;
3151 tree purpose, value;
3153 vec_alloc (v, vec_safe_length (CONSTRUCTOR_ELTS (exp)));
3154 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (exp), idx, purpose, value)
3156 constructor_elt ce = {purpose, copy_constant (value)};
3157 v->quick_push (ce);
3159 CONSTRUCTOR_ELTS (copy) = v;
3160 return copy;
3163 default:
3164 gcc_unreachable ();
3168 /* Return the section into which constant EXP should be placed. */
3170 static section *
3171 get_constant_section (tree exp, unsigned int align)
3173 return targetm.asm_out.select_section (exp,
3174 compute_reloc_for_constant (exp),
3175 align);
3178 /* Return the size of constant EXP in bytes. */
3180 static HOST_WIDE_INT
3181 get_constant_size (tree exp)
3183 HOST_WIDE_INT size;
3185 size = int_size_in_bytes (TREE_TYPE (exp));
3186 if (TREE_CODE (exp) == STRING_CST)
3187 size = MAX (TREE_STRING_LENGTH (exp), size);
3188 return size;
3191 /* Subroutine of output_constant_def:
3192 No constant equal to EXP is known to have been output.
3193 Make a constant descriptor to enter EXP in the hash table.
3194 Assign the label number and construct RTL to refer to the
3195 constant's location in memory.
3196 Caller is responsible for updating the hash table. */
3198 static struct constant_descriptor_tree *
3199 build_constant_desc (tree exp)
3201 struct constant_descriptor_tree *desc;
3202 rtx symbol, rtl;
3203 char label[256];
3204 int labelno;
3205 tree decl;
3207 desc = ggc_alloc<constant_descriptor_tree> ();
3208 desc->value = copy_constant (exp);
3210 /* Create a string containing the label name, in LABEL. */
3211 labelno = const_labelno++;
3212 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3214 /* Construct the VAR_DECL associated with the constant. */
3215 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3216 TREE_TYPE (exp));
3217 DECL_ARTIFICIAL (decl) = 1;
3218 DECL_IGNORED_P (decl) = 1;
3219 TREE_READONLY (decl) = 1;
3220 TREE_STATIC (decl) = 1;
3221 TREE_ADDRESSABLE (decl) = 1;
3222 /* We don't set the RTL yet as this would cause varpool to assume that the
3223 variable is referenced. Moreover, it would just be dropped in LTO mode.
3224 Instead we set the flag that will be recognized in make_decl_rtl. */
3225 DECL_IN_CONSTANT_POOL (decl) = 1;
3226 DECL_INITIAL (decl) = desc->value;
3227 /* ??? CONSTANT_ALIGNMENT hasn't been updated for vector types on most
3228 architectures so use DATA_ALIGNMENT as well, except for strings. */
3229 if (TREE_CODE (exp) == STRING_CST)
3231 #ifdef CONSTANT_ALIGNMENT
3232 DECL_ALIGN (decl) = CONSTANT_ALIGNMENT (exp, DECL_ALIGN (decl));
3233 #endif
3235 else
3236 align_variable (decl, 0);
3238 /* Now construct the SYMBOL_REF and the MEM. */
3239 if (use_object_blocks_p ())
3241 section *sect = get_constant_section (exp, DECL_ALIGN (decl));
3242 symbol = create_block_symbol (ggc_strdup (label),
3243 get_block_for_section (sect), -1);
3245 else
3246 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3247 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3248 SET_SYMBOL_REF_DECL (symbol, decl);
3249 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3251 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3252 set_mem_attributes (rtl, exp, 1);
3253 set_mem_alias_set (rtl, 0);
3254 set_mem_alias_set (rtl, const_alias_set);
3256 /* We cannot share RTX'es in pool entries.
3257 Mark this piece of RTL as required for unsharing. */
3258 RTX_FLAG (rtl, used) = 1;
3260 /* Set flags or add text to the name to record information, such as
3261 that it is a local symbol. If the name is changed, the macro
3262 ASM_OUTPUT_LABELREF will have to know how to strip this
3263 information. This call might invalidate our local variable
3264 SYMBOL; we can't use it afterward. */
3265 targetm.encode_section_info (exp, rtl, true);
3267 desc->rtl = rtl;
3269 return desc;
3272 /* Return an rtx representing a reference to constant data in memory
3273 for the constant expression EXP.
3275 If assembler code for such a constant has already been output,
3276 return an rtx to refer to it.
3277 Otherwise, output such a constant in memory
3278 and generate an rtx for it.
3280 If DEFER is nonzero, this constant can be deferred and output only
3281 if referenced in the function after all optimizations.
3283 `const_desc_table' records which constants already have label strings. */
3286 output_constant_def (tree exp, int defer)
3288 struct constant_descriptor_tree *desc;
3289 struct constant_descriptor_tree key;
3290 void **loc;
3292 /* Look up EXP in the table of constant descriptors. If we didn't find
3293 it, create a new one. */
3294 key.value = exp;
3295 key.hash = const_hash_1 (exp);
3296 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3298 desc = (struct constant_descriptor_tree *) *loc;
3299 if (desc == 0)
3301 desc = build_constant_desc (exp);
3302 desc->hash = key.hash;
3303 *loc = desc;
3306 maybe_output_constant_def_contents (desc, defer);
3307 return desc->rtl;
3310 /* Subroutine of output_constant_def: Decide whether or not we need to
3311 output the constant DESC now, and if so, do it. */
3312 static void
3313 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3314 int defer)
3316 rtx symbol = XEXP (desc->rtl, 0);
3317 tree exp = desc->value;
3319 if (flag_syntax_only)
3320 return;
3322 if (TREE_ASM_WRITTEN (exp))
3323 /* Already output; don't do it again. */
3324 return;
3326 /* We can always defer constants as long as the context allows
3327 doing so. */
3328 if (defer)
3330 /* Increment n_deferred_constants if it exists. It needs to be at
3331 least as large as the number of constants actually referred to
3332 by the function. If it's too small we'll stop looking too early
3333 and fail to emit constants; if it's too large we'll only look
3334 through the entire function when we could have stopped earlier. */
3335 if (cfun)
3336 n_deferred_constants++;
3337 return;
3340 output_constant_def_contents (symbol);
3343 /* Subroutine of output_constant_def_contents. Output the definition
3344 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3345 constant's alignment in bits. */
3347 static void
3348 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3350 HOST_WIDE_INT size;
3352 size = get_constant_size (exp);
3354 /* Do any machine/system dependent processing of the constant. */
3355 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3357 /* Output the value of EXP. */
3358 output_constant (exp, size, align);
3361 /* We must output the constant data referred to by SYMBOL; do so. */
3363 static void
3364 output_constant_def_contents (rtx symbol)
3366 tree decl = SYMBOL_REF_DECL (symbol);
3367 tree exp = DECL_INITIAL (decl);
3368 unsigned int align;
3369 bool asan_protected = false;
3371 /* Make sure any other constants whose addresses appear in EXP
3372 are assigned label numbers. */
3373 output_addressed_constants (exp);
3375 /* We are no longer deferring this constant. */
3376 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3378 if ((flag_sanitize & SANITIZE_ADDRESS)
3379 && TREE_CODE (exp) == STRING_CST
3380 && asan_protect_global (exp))
3382 asan_protected = true;
3383 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
3384 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
3387 /* If the constant is part of an object block, make sure that the
3388 decl has been positioned within its block, but do not write out
3389 its definition yet. output_object_blocks will do that later. */
3390 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3391 place_block_symbol (symbol);
3392 else
3394 align = DECL_ALIGN (decl);
3395 switch_to_section (get_constant_section (exp, align));
3396 if (align > BITS_PER_UNIT)
3397 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3398 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3399 if (asan_protected)
3401 HOST_WIDE_INT size = get_constant_size (exp);
3402 assemble_zeros (asan_red_zone_size (size));
3407 /* Look up EXP in the table of constant descriptors. Return the rtl
3408 if it has been emitted, else null. */
3411 lookup_constant_def (tree exp)
3413 struct constant_descriptor_tree *desc;
3414 struct constant_descriptor_tree key;
3416 key.value = exp;
3417 key.hash = const_hash_1 (exp);
3418 desc = (struct constant_descriptor_tree *)
3419 htab_find_with_hash (const_desc_htab, &key, key.hash);
3421 return (desc ? desc->rtl : NULL_RTX);
3424 /* Return a tree representing a reference to constant data in memory
3425 for the constant expression EXP.
3427 This is the counterpart of output_constant_def at the Tree level. */
3429 tree
3430 tree_output_constant_def (tree exp)
3432 struct constant_descriptor_tree *desc, key;
3433 void **loc;
3434 tree decl;
3436 /* Look up EXP in the table of constant descriptors. If we didn't find
3437 it, create a new one. */
3438 key.value = exp;
3439 key.hash = const_hash_1 (exp);
3440 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3442 desc = (struct constant_descriptor_tree *) *loc;
3443 if (desc == 0)
3445 desc = build_constant_desc (exp);
3446 desc->hash = key.hash;
3447 *loc = desc;
3450 decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3451 varpool_finalize_decl (decl);
3452 return decl;
3455 /* Used in the hash tables to avoid outputting the same constant
3456 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3457 are output once per function, not once per file. */
3458 /* ??? Only a few targets need per-function constant pools. Most
3459 can use one per-file pool. Should add a targetm bit to tell the
3460 difference. */
3462 struct GTY(()) rtx_constant_pool {
3463 /* Pointers to first and last constant in pool, as ordered by offset. */
3464 struct constant_descriptor_rtx *first;
3465 struct constant_descriptor_rtx *last;
3467 /* Hash facility for making memory-constants from constant rtl-expressions.
3468 It is used on RISC machines where immediate integer arguments and
3469 constant addresses are restricted so that such constants must be stored
3470 in memory. */
3471 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_htab;
3473 /* Current offset in constant pool (does not include any
3474 machine-specific header). */
3475 HOST_WIDE_INT offset;
3478 struct GTY((chain_next ("%h.next"))) constant_descriptor_rtx {
3479 struct constant_descriptor_rtx *next;
3480 rtx mem;
3481 rtx sym;
3482 rtx constant;
3483 HOST_WIDE_INT offset;
3484 hashval_t hash;
3485 enum machine_mode mode;
3486 unsigned int align;
3487 int labelno;
3488 int mark;
3491 /* Hash and compare functions for const_rtx_htab. */
3493 static hashval_t
3494 const_desc_rtx_hash (const void *ptr)
3496 const struct constant_descriptor_rtx *const desc
3497 = (const struct constant_descriptor_rtx *) ptr;
3498 return desc->hash;
3501 static int
3502 const_desc_rtx_eq (const void *a, const void *b)
3504 const struct constant_descriptor_rtx *const x
3505 = (const struct constant_descriptor_rtx *) a;
3506 const struct constant_descriptor_rtx *const y
3507 = (const struct constant_descriptor_rtx *) b;
3509 if (x->mode != y->mode)
3510 return 0;
3511 return rtx_equal_p (x->constant, y->constant);
3514 /* This is the worker function for const_rtx_hash, called via for_each_rtx. */
3516 static int
3517 const_rtx_hash_1 (rtx *xp, void *data)
3519 unsigned HOST_WIDE_INT hwi;
3520 enum machine_mode mode;
3521 enum rtx_code code;
3522 hashval_t h, *hp;
3523 rtx x;
3524 int i;
3526 x = *xp;
3527 code = GET_CODE (x);
3528 mode = GET_MODE (x);
3529 h = (hashval_t) code * 1048573 + mode;
3531 switch (code)
3533 case CONST_INT:
3534 hwi = INTVAL (x);
3536 fold_hwi:
3538 int shift = sizeof (hashval_t) * CHAR_BIT;
3539 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3541 h ^= (hashval_t) hwi;
3542 for (i = 1; i < n; ++i)
3544 hwi >>= shift;
3545 h ^= (hashval_t) hwi;
3548 break;
3550 case CONST_WIDE_INT:
3551 hwi = GET_MODE_PRECISION (mode);
3553 for (i = 0; i < CONST_WIDE_INT_NUNITS (x); i++)
3554 hwi ^= CONST_WIDE_INT_ELT (x, i);
3555 goto fold_hwi;
3558 case CONST_DOUBLE:
3559 if (TARGET_SUPPORTS_WIDE_INT == 0 && mode == VOIDmode)
3561 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3562 goto fold_hwi;
3564 else
3565 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3566 break;
3568 case CONST_FIXED:
3569 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3570 break;
3572 case CONST_VECTOR:
3574 int i;
3575 for (i = XVECLEN (x, 0); i-- > 0; )
3576 h = h * 251 + const_rtx_hash_1 (&XVECEXP (x, 0, i), data);
3578 break;
3580 case SYMBOL_REF:
3581 h ^= htab_hash_string (XSTR (x, 0));
3582 break;
3584 case LABEL_REF:
3585 h = h * 251 + CODE_LABEL_NUMBER (XEXP (x, 0));
3586 break;
3588 case UNSPEC:
3589 case UNSPEC_VOLATILE:
3590 h = h * 251 + XINT (x, 1);
3591 break;
3593 default:
3594 break;
3597 hp = (hashval_t *) data;
3598 *hp = *hp * 509 + h;
3599 return 0;
3602 /* Compute a hash value for X, which should be a constant. */
3604 static hashval_t
3605 const_rtx_hash (rtx x)
3607 hashval_t h = 0;
3608 for_each_rtx (&x, const_rtx_hash_1, &h);
3609 return h;
3613 /* Create and return a new rtx constant pool. */
3615 static struct rtx_constant_pool *
3616 create_constant_pool (void)
3618 struct rtx_constant_pool *pool;
3620 pool = ggc_alloc<rtx_constant_pool> ();
3621 pool->const_rtx_htab = htab_create_ggc (31, const_desc_rtx_hash,
3622 const_desc_rtx_eq, NULL);
3623 pool->first = NULL;
3624 pool->last = NULL;
3625 pool->offset = 0;
3626 return pool;
3629 /* Initialize constant pool hashing for a new function. */
3631 void
3632 init_varasm_status (void)
3634 crtl->varasm.pool = create_constant_pool ();
3635 crtl->varasm.deferred_constants = 0;
3638 /* Given a MINUS expression, simplify it if both sides
3639 include the same symbol. */
3642 simplify_subtraction (rtx x)
3644 rtx r = simplify_rtx (x);
3645 return r ? r : x;
3648 /* Given a constant rtx X, make (or find) a memory constant for its value
3649 and return a MEM rtx to refer to it in memory. */
3652 force_const_mem (enum machine_mode mode, rtx x)
3654 struct constant_descriptor_rtx *desc, tmp;
3655 struct rtx_constant_pool *pool;
3656 char label[256];
3657 rtx def, symbol;
3658 hashval_t hash;
3659 unsigned int align;
3660 void **slot;
3662 /* If we're not allowed to drop X into the constant pool, don't. */
3663 if (targetm.cannot_force_const_mem (mode, x))
3664 return NULL_RTX;
3666 /* Record that this function has used a constant pool entry. */
3667 crtl->uses_const_pool = 1;
3669 /* Decide which pool to use. */
3670 pool = (targetm.use_blocks_for_constant_p (mode, x)
3671 ? shared_constant_pool
3672 : crtl->varasm.pool);
3674 /* Lookup the value in the hashtable. */
3675 tmp.constant = x;
3676 tmp.mode = mode;
3677 hash = const_rtx_hash (x);
3678 slot = htab_find_slot_with_hash (pool->const_rtx_htab, &tmp, hash, INSERT);
3679 desc = (struct constant_descriptor_rtx *) *slot;
3681 /* If the constant was already present, return its memory. */
3682 if (desc)
3683 return copy_rtx (desc->mem);
3685 /* Otherwise, create a new descriptor. */
3686 desc = ggc_alloc<constant_descriptor_rtx> ();
3687 *slot = desc;
3689 /* Align the location counter as required by EXP's data type. */
3690 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3691 #ifdef CONSTANT_ALIGNMENT
3693 tree type = lang_hooks.types.type_for_mode (mode, 0);
3694 if (type != NULL_TREE)
3695 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3697 #endif
3699 pool->offset += (align / BITS_PER_UNIT) - 1;
3700 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3702 desc->next = NULL;
3703 desc->constant = copy_rtx (tmp.constant);
3704 desc->offset = pool->offset;
3705 desc->hash = hash;
3706 desc->mode = mode;
3707 desc->align = align;
3708 desc->labelno = const_labelno;
3709 desc->mark = 0;
3711 pool->offset += GET_MODE_SIZE (mode);
3712 if (pool->last)
3713 pool->last->next = desc;
3714 else
3715 pool->first = pool->last = desc;
3716 pool->last = desc;
3718 /* Create a string containing the label name, in LABEL. */
3719 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3720 ++const_labelno;
3722 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3723 the constants pool. */
3724 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3726 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3727 symbol = create_block_symbol (ggc_strdup (label),
3728 get_block_for_section (sect), -1);
3730 else
3731 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3732 desc->sym = symbol;
3733 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3734 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3735 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3737 /* Construct the MEM. */
3738 desc->mem = def = gen_const_mem (mode, symbol);
3739 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3740 set_mem_align (def, align);
3742 /* If we're dropping a label to the constant pool, make sure we
3743 don't delete it. */
3744 if (GET_CODE (x) == LABEL_REF)
3745 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3747 return copy_rtx (def);
3750 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3753 get_pool_constant (rtx addr)
3755 return SYMBOL_REF_CONSTANT (addr)->constant;
3758 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3759 and whether it has been output or not. */
3762 get_pool_constant_mark (rtx addr, bool *pmarked)
3764 struct constant_descriptor_rtx *desc;
3766 desc = SYMBOL_REF_CONSTANT (addr);
3767 *pmarked = (desc->mark != 0);
3768 return desc->constant;
3771 /* Similar, return the mode. */
3773 enum machine_mode
3774 get_pool_mode (const_rtx addr)
3776 return SYMBOL_REF_CONSTANT (addr)->mode;
3779 /* Return the size of the constant pool. */
3782 get_pool_size (void)
3784 return crtl->varasm.pool->offset;
3787 /* Worker function for output_constant_pool_1. Emit assembly for X
3788 in MODE with known alignment ALIGN. */
3790 static void
3791 output_constant_pool_2 (enum machine_mode mode, rtx x, unsigned int align)
3793 switch (GET_MODE_CLASS (mode))
3795 case MODE_FLOAT:
3796 case MODE_DECIMAL_FLOAT:
3798 REAL_VALUE_TYPE r;
3800 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3801 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3802 assemble_real (r, mode, align);
3803 break;
3806 case MODE_INT:
3807 case MODE_PARTIAL_INT:
3808 case MODE_FRACT:
3809 case MODE_UFRACT:
3810 case MODE_ACCUM:
3811 case MODE_UACCUM:
3812 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3813 break;
3815 case MODE_VECTOR_FLOAT:
3816 case MODE_VECTOR_INT:
3817 case MODE_VECTOR_FRACT:
3818 case MODE_VECTOR_UFRACT:
3819 case MODE_VECTOR_ACCUM:
3820 case MODE_VECTOR_UACCUM:
3822 int i, units;
3823 enum machine_mode submode = GET_MODE_INNER (mode);
3824 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3826 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3827 units = CONST_VECTOR_NUNITS (x);
3829 for (i = 0; i < units; i++)
3831 rtx elt = CONST_VECTOR_ELT (x, i);
3832 output_constant_pool_2 (submode, elt, i ? subalign : align);
3835 break;
3837 default:
3838 gcc_unreachable ();
3842 /* Worker function for output_constant_pool. Emit constant DESC,
3843 giving it ALIGN bits of alignment. */
3845 static void
3846 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3847 unsigned int align)
3849 rtx x, tmp;
3851 x = desc->constant;
3853 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3854 whose CODE_LABEL has been deleted. This can occur if a jump table
3855 is eliminated by optimization. If so, write a constant of zero
3856 instead. Note that this can also happen by turning the
3857 CODE_LABEL into a NOTE. */
3858 /* ??? This seems completely and utterly wrong. Certainly it's
3859 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3860 functioning even with INSN_DELETED_P and friends. */
3862 tmp = x;
3863 switch (GET_CODE (tmp))
3865 case CONST:
3866 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3867 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
3868 break;
3869 tmp = XEXP (XEXP (tmp, 0), 0);
3870 /* FALLTHRU */
3872 case LABEL_REF:
3873 tmp = XEXP (tmp, 0);
3874 gcc_assert (!INSN_DELETED_P (tmp));
3875 gcc_assert (!NOTE_P (tmp)
3876 || NOTE_KIND (tmp) != NOTE_INSN_DELETED);
3877 break;
3879 default:
3880 break;
3883 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3884 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3885 align, desc->labelno, done);
3886 #endif
3888 assemble_align (align);
3890 /* Output the label. */
3891 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3893 /* Output the data. */
3894 output_constant_pool_2 (desc->mode, x, align);
3896 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3897 sections have proper size. */
3898 if (align > GET_MODE_BITSIZE (desc->mode)
3899 && in_section
3900 && (in_section->common.flags & SECTION_MERGE))
3901 assemble_align (align);
3903 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3904 done:
3905 #endif
3906 return;
3909 /* Given a SYMBOL_REF CURRENT_RTX, mark it and all constants it refers
3910 to as used. Emit referenced deferred strings. This function can
3911 be used with for_each_rtx to mark all SYMBOL_REFs in an rtx. */
3913 static int
3914 mark_constant (rtx *current_rtx, void *data ATTRIBUTE_UNUSED)
3916 rtx x = *current_rtx;
3918 if (x == NULL_RTX || GET_CODE (x) != SYMBOL_REF)
3919 return 0;
3921 if (CONSTANT_POOL_ADDRESS_P (x))
3923 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
3924 if (desc->mark == 0)
3926 desc->mark = 1;
3927 for_each_rtx (&desc->constant, mark_constant, NULL);
3930 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3932 tree decl = SYMBOL_REF_DECL (x);
3933 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
3935 n_deferred_constants--;
3936 output_constant_def_contents (x);
3940 return -1;
3943 /* Look through appropriate parts of INSN, marking all entries in the
3944 constant pool which are actually being used. Entries that are only
3945 referenced by other constants are also marked as used. Emit
3946 deferred strings that are used. */
3948 static void
3949 mark_constants (rtx insn)
3951 if (!INSN_P (insn))
3952 return;
3954 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3955 insns, not any notes that may be attached. We don't want to mark
3956 a constant just because it happens to appear in a REG_EQUIV note. */
3957 if (GET_CODE (PATTERN (insn)) == SEQUENCE)
3959 rtx seq = PATTERN (insn);
3960 int i, n = XVECLEN (seq, 0);
3961 for (i = 0; i < n; ++i)
3963 rtx subinsn = XVECEXP (seq, 0, i);
3964 if (INSN_P (subinsn))
3965 for_each_rtx (&PATTERN (subinsn), mark_constant, NULL);
3968 else
3969 for_each_rtx (&PATTERN (insn), mark_constant, NULL);
3972 /* Look through the instructions for this function, and mark all the
3973 entries in POOL which are actually being used. Emit deferred constants
3974 which have indeed been used. */
3976 static void
3977 mark_constant_pool (void)
3979 rtx insn;
3981 if (!crtl->uses_const_pool && n_deferred_constants == 0)
3982 return;
3984 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3985 mark_constants (insn);
3988 /* Write all the constants in POOL. */
3990 static void
3991 output_constant_pool_contents (struct rtx_constant_pool *pool)
3993 struct constant_descriptor_rtx *desc;
3995 for (desc = pool->first; desc ; desc = desc->next)
3996 if (desc->mark)
3998 /* If the constant is part of an object_block, make sure that
3999 the constant has been positioned within its block, but do not
4000 write out its definition yet. output_object_blocks will do
4001 that later. */
4002 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
4003 && SYMBOL_REF_BLOCK (desc->sym))
4004 place_block_symbol (desc->sym);
4005 else
4007 switch_to_section (targetm.asm_out.select_rtx_section
4008 (desc->mode, desc->constant, desc->align));
4009 output_constant_pool_1 (desc, desc->align);
4014 /* Mark all constants that are used in the current function, then write
4015 out the function's private constant pool. */
4017 static void
4018 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
4019 tree fndecl ATTRIBUTE_UNUSED)
4021 struct rtx_constant_pool *pool = crtl->varasm.pool;
4023 /* It is possible for gcc to call force_const_mem and then to later
4024 discard the instructions which refer to the constant. In such a
4025 case we do not need to output the constant. */
4026 mark_constant_pool ();
4028 #ifdef ASM_OUTPUT_POOL_PROLOGUE
4029 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
4030 #endif
4032 output_constant_pool_contents (pool);
4034 #ifdef ASM_OUTPUT_POOL_EPILOGUE
4035 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
4036 #endif
4039 /* Write the contents of the shared constant pool. */
4041 void
4042 output_shared_constant_pool (void)
4044 output_constant_pool_contents (shared_constant_pool);
4047 /* Determine what kind of relocations EXP may need. */
4050 compute_reloc_for_constant (tree exp)
4052 int reloc = 0, reloc2;
4053 tree tem;
4055 switch (TREE_CODE (exp))
4057 case ADDR_EXPR:
4058 case FDESC_EXPR:
4059 /* Go inside any operations that get_inner_reference can handle and see
4060 if what's inside is a constant: no need to do anything here for
4061 addresses of variables or functions. */
4062 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4063 tem = TREE_OPERAND (tem, 0))
4066 if (TREE_CODE (tem) == MEM_REF
4067 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4069 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4070 break;
4073 if (!targetm.binds_local_p (tem))
4074 reloc |= 2;
4075 else
4076 reloc |= 1;
4077 break;
4079 case PLUS_EXPR:
4080 case POINTER_PLUS_EXPR:
4081 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4082 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4083 break;
4085 case MINUS_EXPR:
4086 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4087 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4088 /* The difference of two local labels is computable at link time. */
4089 if (reloc == 1 && reloc2 == 1)
4090 reloc = 0;
4091 else
4092 reloc |= reloc2;
4093 break;
4095 CASE_CONVERT:
4096 case VIEW_CONVERT_EXPR:
4097 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4098 break;
4100 case CONSTRUCTOR:
4102 unsigned HOST_WIDE_INT idx;
4103 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4104 if (tem != 0)
4105 reloc |= compute_reloc_for_constant (tem);
4107 break;
4109 default:
4110 break;
4112 return reloc;
4115 /* Find all the constants whose addresses are referenced inside of EXP,
4116 and make sure assembler code with a label has been output for each one.
4117 Indicate whether an ADDR_EXPR has been encountered. */
4119 static void
4120 output_addressed_constants (tree exp)
4122 tree tem;
4124 switch (TREE_CODE (exp))
4126 case ADDR_EXPR:
4127 case FDESC_EXPR:
4128 /* Go inside any operations that get_inner_reference can handle and see
4129 if what's inside is a constant: no need to do anything here for
4130 addresses of variables or functions. */
4131 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4132 tem = TREE_OPERAND (tem, 0))
4135 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4136 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4137 tem = DECL_INITIAL (tem);
4139 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4140 output_constant_def (tem, 0);
4142 if (TREE_CODE (tem) == MEM_REF)
4143 output_addressed_constants (TREE_OPERAND (tem, 0));
4144 break;
4146 case PLUS_EXPR:
4147 case POINTER_PLUS_EXPR:
4148 case MINUS_EXPR:
4149 output_addressed_constants (TREE_OPERAND (exp, 1));
4150 /* Fall through. */
4152 CASE_CONVERT:
4153 case VIEW_CONVERT_EXPR:
4154 output_addressed_constants (TREE_OPERAND (exp, 0));
4155 break;
4157 case CONSTRUCTOR:
4159 unsigned HOST_WIDE_INT idx;
4160 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4161 if (tem != 0)
4162 output_addressed_constants (tem);
4164 break;
4166 default:
4167 break;
4171 /* Whether a constructor CTOR is a valid static constant initializer if all
4172 its elements are. This used to be internal to initializer_constant_valid_p
4173 and has been exposed to let other functions like categorize_ctor_elements
4174 evaluate the property while walking a constructor for other purposes. */
4176 bool
4177 constructor_static_from_elts_p (const_tree ctor)
4179 return (TREE_CONSTANT (ctor)
4180 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4181 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4182 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4185 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4186 tree *cache);
4188 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4189 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4190 which are valid when ENDTYPE is an integer of any size; in
4191 particular, this does not accept a pointer minus a constant. This
4192 returns null_pointer_node if the VALUE is an absolute constant
4193 which can be used to initialize a static variable. Otherwise it
4194 returns NULL. */
4196 static tree
4197 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4199 tree op0, op1;
4201 if (!INTEGRAL_TYPE_P (endtype))
4202 return NULL_TREE;
4204 op0 = TREE_OPERAND (value, 0);
4205 op1 = TREE_OPERAND (value, 1);
4207 /* Like STRIP_NOPS except allow the operand mode to widen. This
4208 works around a feature of fold that simplifies (int)(p1 - p2) to
4209 ((int)p1 - (int)p2) under the theory that the narrower operation
4210 is cheaper. */
4212 while (CONVERT_EXPR_P (op0)
4213 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4215 tree inner = TREE_OPERAND (op0, 0);
4216 if (inner == error_mark_node
4217 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4218 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
4219 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4220 break;
4221 op0 = inner;
4224 while (CONVERT_EXPR_P (op1)
4225 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4227 tree inner = TREE_OPERAND (op1, 0);
4228 if (inner == error_mark_node
4229 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4230 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
4231 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4232 break;
4233 op1 = inner;
4236 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4237 if (!op0)
4238 return NULL_TREE;
4240 op1 = initializer_constant_valid_p_1 (op1, endtype,
4241 cache ? cache + 2 : NULL);
4242 /* Both initializers must be known. */
4243 if (op1)
4245 if (op0 == op1
4246 && (op0 == null_pointer_node
4247 || TREE_CODE (value) == MINUS_EXPR))
4248 return null_pointer_node;
4250 /* Support differences between labels. */
4251 if (TREE_CODE (op0) == LABEL_DECL
4252 && TREE_CODE (op1) == LABEL_DECL)
4253 return null_pointer_node;
4255 if (TREE_CODE (op0) == STRING_CST
4256 && TREE_CODE (op1) == STRING_CST
4257 && operand_equal_p (op0, op1, 1))
4258 return null_pointer_node;
4261 return NULL_TREE;
4264 /* Helper function of initializer_constant_valid_p.
4265 Return nonzero if VALUE is a valid constant-valued expression
4266 for use in initializing a static variable; one that can be an
4267 element of a "constant" initializer.
4269 Return null_pointer_node if the value is absolute;
4270 if it is relocatable, return the variable that determines the relocation.
4271 We assume that VALUE has been folded as much as possible;
4272 therefore, we do not need to check for such things as
4273 arithmetic-combinations of integers.
4275 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4277 static tree
4278 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4280 tree ret;
4282 switch (TREE_CODE (value))
4284 case CONSTRUCTOR:
4285 if (constructor_static_from_elts_p (value))
4287 unsigned HOST_WIDE_INT idx;
4288 tree elt;
4289 bool absolute = true;
4291 if (cache && cache[0] == value)
4292 return cache[1];
4293 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4295 tree reloc;
4296 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4297 NULL);
4298 if (!reloc)
4300 if (cache)
4302 cache[0] = value;
4303 cache[1] = NULL_TREE;
4305 return NULL_TREE;
4307 if (reloc != null_pointer_node)
4308 absolute = false;
4310 /* For a non-absolute relocation, there is no single
4311 variable that can be "the variable that determines the
4312 relocation." */
4313 if (cache)
4315 cache[0] = value;
4316 cache[1] = absolute ? null_pointer_node : error_mark_node;
4318 return absolute ? null_pointer_node : error_mark_node;
4321 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4323 case INTEGER_CST:
4324 case VECTOR_CST:
4325 case REAL_CST:
4326 case FIXED_CST:
4327 case STRING_CST:
4328 case COMPLEX_CST:
4329 return null_pointer_node;
4331 case ADDR_EXPR:
4332 case FDESC_EXPR:
4334 tree op0 = staticp (TREE_OPERAND (value, 0));
4335 if (op0)
4337 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4338 to be a constant, this is old-skool offsetof-like nonsense. */
4339 if (TREE_CODE (op0) == INDIRECT_REF
4340 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4341 return null_pointer_node;
4342 /* Taking the address of a nested function involves a trampoline,
4343 unless we don't need or want one. */
4344 if (TREE_CODE (op0) == FUNCTION_DECL
4345 && DECL_STATIC_CHAIN (op0)
4346 && !TREE_NO_TRAMPOLINE (value))
4347 return NULL_TREE;
4348 /* "&{...}" requires a temporary to hold the constructed
4349 object. */
4350 if (TREE_CODE (op0) == CONSTRUCTOR)
4351 return NULL_TREE;
4353 return op0;
4356 case NON_LVALUE_EXPR:
4357 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4358 endtype, cache);
4360 case VIEW_CONVERT_EXPR:
4362 tree src = TREE_OPERAND (value, 0);
4363 tree src_type = TREE_TYPE (src);
4364 tree dest_type = TREE_TYPE (value);
4366 /* Allow view-conversions from aggregate to non-aggregate type only
4367 if the bit pattern is fully preserved afterwards; otherwise, the
4368 RTL expander won't be able to apply a subsequent transformation
4369 to the underlying constructor. */
4370 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4372 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4373 return initializer_constant_valid_p_1 (src, endtype, cache);
4374 else
4375 return NULL_TREE;
4378 /* Allow all other kinds of view-conversion. */
4379 return initializer_constant_valid_p_1 (src, endtype, cache);
4382 CASE_CONVERT:
4384 tree src = TREE_OPERAND (value, 0);
4385 tree src_type = TREE_TYPE (src);
4386 tree dest_type = TREE_TYPE (value);
4388 /* Allow conversions between pointer types, floating-point
4389 types, and offset types. */
4390 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4391 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4392 || (TREE_CODE (dest_type) == OFFSET_TYPE
4393 && TREE_CODE (src_type) == OFFSET_TYPE))
4394 return initializer_constant_valid_p_1 (src, endtype, cache);
4396 /* Allow length-preserving conversions between integer types. */
4397 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4398 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4399 return initializer_constant_valid_p_1 (src, endtype, cache);
4401 /* Allow conversions between other integer types only if
4402 explicit value. */
4403 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type))
4405 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4406 if (inner == null_pointer_node)
4407 return null_pointer_node;
4408 break;
4411 /* Allow (int) &foo provided int is as wide as a pointer. */
4412 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4413 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4414 return initializer_constant_valid_p_1 (src, endtype, cache);
4416 /* Likewise conversions from int to pointers, but also allow
4417 conversions from 0. */
4418 if ((POINTER_TYPE_P (dest_type)
4419 || TREE_CODE (dest_type) == OFFSET_TYPE)
4420 && INTEGRAL_TYPE_P (src_type))
4422 if (TREE_CODE (src) == INTEGER_CST
4423 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4424 return null_pointer_node;
4425 if (integer_zerop (src))
4426 return null_pointer_node;
4427 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4428 return initializer_constant_valid_p_1 (src, endtype, cache);
4431 /* Allow conversions to struct or union types if the value
4432 inside is okay. */
4433 if (TREE_CODE (dest_type) == RECORD_TYPE
4434 || TREE_CODE (dest_type) == UNION_TYPE)
4435 return initializer_constant_valid_p_1 (src, endtype, cache);
4437 break;
4439 case POINTER_PLUS_EXPR:
4440 case PLUS_EXPR:
4441 /* Any valid floating-point constants will have been folded by now;
4442 with -frounding-math we hit this with addition of two constants. */
4443 if (TREE_CODE (endtype) == REAL_TYPE)
4444 return NULL_TREE;
4445 if (cache && cache[0] == value)
4446 return cache[1];
4447 if (! INTEGRAL_TYPE_P (endtype)
4448 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4450 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4451 tree valid0
4452 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4453 endtype, ncache);
4454 tree valid1
4455 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4456 endtype, ncache + 2);
4457 /* If either term is absolute, use the other term's relocation. */
4458 if (valid0 == null_pointer_node)
4459 ret = valid1;
4460 else if (valid1 == null_pointer_node)
4461 ret = valid0;
4462 /* Support narrowing pointer differences. */
4463 else
4464 ret = narrowing_initializer_constant_valid_p (value, endtype,
4465 ncache);
4467 else
4468 /* Support narrowing pointer differences. */
4469 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4470 if (cache)
4472 cache[0] = value;
4473 cache[1] = ret;
4475 return ret;
4477 case MINUS_EXPR:
4478 if (TREE_CODE (endtype) == REAL_TYPE)
4479 return NULL_TREE;
4480 if (cache && cache[0] == value)
4481 return cache[1];
4482 if (! INTEGRAL_TYPE_P (endtype)
4483 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4485 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4486 tree valid0
4487 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4488 endtype, ncache);
4489 tree valid1
4490 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4491 endtype, ncache + 2);
4492 /* Win if second argument is absolute. */
4493 if (valid1 == null_pointer_node)
4494 ret = valid0;
4495 /* Win if both arguments have the same relocation.
4496 Then the value is absolute. */
4497 else if (valid0 == valid1 && valid0 != 0)
4498 ret = null_pointer_node;
4499 /* Since GCC guarantees that string constants are unique in the
4500 generated code, a subtraction between two copies of the same
4501 constant string is absolute. */
4502 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4503 && valid1 && TREE_CODE (valid1) == STRING_CST
4504 && operand_equal_p (valid0, valid1, 1))
4505 ret = null_pointer_node;
4506 /* Support narrowing differences. */
4507 else
4508 ret = narrowing_initializer_constant_valid_p (value, endtype,
4509 ncache);
4511 else
4512 /* Support narrowing differences. */
4513 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4514 if (cache)
4516 cache[0] = value;
4517 cache[1] = ret;
4519 return ret;
4521 default:
4522 break;
4525 return NULL_TREE;
4528 /* Return nonzero if VALUE is a valid constant-valued expression
4529 for use in initializing a static variable; one that can be an
4530 element of a "constant" initializer.
4532 Return null_pointer_node if the value is absolute;
4533 if it is relocatable, return the variable that determines the relocation.
4534 We assume that VALUE has been folded as much as possible;
4535 therefore, we do not need to check for such things as
4536 arithmetic-combinations of integers. */
4537 tree
4538 initializer_constant_valid_p (tree value, tree endtype)
4540 return initializer_constant_valid_p_1 (value, endtype, NULL);
4543 /* Return true if VALUE is a valid constant-valued expression
4544 for use in initializing a static bit-field; one that can be
4545 an element of a "constant" initializer. */
4547 bool
4548 initializer_constant_valid_for_bitfield_p (tree value)
4550 /* For bitfields we support integer constants or possibly nested aggregates
4551 of such. */
4552 switch (TREE_CODE (value))
4554 case CONSTRUCTOR:
4556 unsigned HOST_WIDE_INT idx;
4557 tree elt;
4559 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4560 if (!initializer_constant_valid_for_bitfield_p (elt))
4561 return false;
4562 return true;
4565 case INTEGER_CST:
4566 case REAL_CST:
4567 return true;
4569 case VIEW_CONVERT_EXPR:
4570 case NON_LVALUE_EXPR:
4571 return
4572 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4574 default:
4575 break;
4578 return false;
4581 /* output_constructor outer state of relevance in recursive calls, typically
4582 for nested aggregate bitfields. */
4584 typedef struct {
4585 unsigned int bit_offset; /* current position in ... */
4586 int byte; /* ... the outer byte buffer. */
4587 } oc_outer_state;
4589 static unsigned HOST_WIDE_INT
4590 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int,
4591 oc_outer_state *);
4593 /* Output assembler code for constant EXP, with no label.
4594 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4595 Assumes output_addressed_constants has been done on EXP already.
4597 Generate at least SIZE bytes of assembler data, padding at the end
4598 with zeros if necessary. SIZE must always be specified. The returned
4599 value is the actual number of bytes of assembler data generated, which
4600 may be bigger than SIZE if the object contains a variable length field.
4602 SIZE is important for structure constructors,
4603 since trailing members may have been omitted from the constructor.
4604 It is also important for initialization of arrays from string constants
4605 since the full length of the string constant might not be wanted.
4606 It is also needed for initialization of unions, where the initializer's
4607 type is just one member, and that may not be as long as the union.
4609 There a case in which we would fail to output exactly SIZE bytes:
4610 for a structure constructor that wants to produce more than SIZE bytes.
4611 But such constructors will never be generated for any possible input.
4613 ALIGN is the alignment of the data in bits. */
4615 static unsigned HOST_WIDE_INT
4616 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align)
4618 enum tree_code code;
4619 unsigned HOST_WIDE_INT thissize;
4621 if (size == 0 || flag_syntax_only)
4622 return size;
4624 /* See if we're trying to initialize a pointer in a non-default mode
4625 to the address of some declaration somewhere. If the target says
4626 the mode is valid for pointers, assume the target has a way of
4627 resolving it. */
4628 if (TREE_CODE (exp) == NOP_EXPR
4629 && POINTER_TYPE_P (TREE_TYPE (exp))
4630 && targetm.addr_space.valid_pointer_mode
4631 (TYPE_MODE (TREE_TYPE (exp)),
4632 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4634 tree saved_type = TREE_TYPE (exp);
4636 /* Peel off any intermediate conversions-to-pointer for valid
4637 pointer modes. */
4638 while (TREE_CODE (exp) == NOP_EXPR
4639 && POINTER_TYPE_P (TREE_TYPE (exp))
4640 && targetm.addr_space.valid_pointer_mode
4641 (TYPE_MODE (TREE_TYPE (exp)),
4642 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4643 exp = TREE_OPERAND (exp, 0);
4645 /* If what we're left with is the address of something, we can
4646 convert the address to the final type and output it that
4647 way. */
4648 if (TREE_CODE (exp) == ADDR_EXPR)
4649 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4650 /* Likewise for constant ints. */
4651 else if (TREE_CODE (exp) == INTEGER_CST)
4652 exp = wide_int_to_tree (saved_type, exp);
4656 /* Eliminate any conversions since we'll be outputting the underlying
4657 constant. */
4658 while (CONVERT_EXPR_P (exp)
4659 || TREE_CODE (exp) == NON_LVALUE_EXPR
4660 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4662 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4663 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4665 /* Make sure eliminating the conversion is really a no-op, except with
4666 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4667 union types to allow for Ada unchecked unions. */
4668 if (type_size > op_size
4669 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4670 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4671 /* Keep the conversion. */
4672 break;
4673 else
4674 exp = TREE_OPERAND (exp, 0);
4677 code = TREE_CODE (TREE_TYPE (exp));
4678 thissize = int_size_in_bytes (TREE_TYPE (exp));
4680 /* Allow a constructor with no elements for any data type.
4681 This means to fill the space with zeros. */
4682 if (TREE_CODE (exp) == CONSTRUCTOR
4683 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4685 assemble_zeros (size);
4686 return size;
4689 if (TREE_CODE (exp) == FDESC_EXPR)
4691 #ifdef ASM_OUTPUT_FDESC
4692 HOST_WIDE_INT part = tree_to_shwi (TREE_OPERAND (exp, 1));
4693 tree decl = TREE_OPERAND (exp, 0);
4694 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4695 #else
4696 gcc_unreachable ();
4697 #endif
4698 return size;
4701 /* Now output the underlying data. If we've handling the padding, return.
4702 Otherwise, break and ensure SIZE is the size written. */
4703 switch (code)
4705 case BOOLEAN_TYPE:
4706 case INTEGER_TYPE:
4707 case ENUMERAL_TYPE:
4708 case POINTER_TYPE:
4709 case REFERENCE_TYPE:
4710 case OFFSET_TYPE:
4711 case FIXED_POINT_TYPE:
4712 case NULLPTR_TYPE:
4713 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
4714 EXPAND_INITIALIZER),
4715 MIN (size, thissize), align, 0))
4716 error ("initializer for integer/fixed-point value is too complicated");
4717 break;
4719 case REAL_TYPE:
4720 if (TREE_CODE (exp) != REAL_CST)
4721 error ("initializer for floating value is not a floating constant");
4722 else
4723 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)), align);
4724 break;
4726 case COMPLEX_TYPE:
4727 output_constant (TREE_REALPART (exp), thissize / 2, align);
4728 output_constant (TREE_IMAGPART (exp), thissize / 2,
4729 min_align (align, BITS_PER_UNIT * (thissize / 2)));
4730 break;
4732 case ARRAY_TYPE:
4733 case VECTOR_TYPE:
4734 switch (TREE_CODE (exp))
4736 case CONSTRUCTOR:
4737 return output_constructor (exp, size, align, NULL);
4738 case STRING_CST:
4739 thissize
4740 = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4741 assemble_string (TREE_STRING_POINTER (exp), thissize);
4742 break;
4743 case VECTOR_CST:
4745 enum machine_mode inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4746 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4747 int elt_size = GET_MODE_SIZE (inner);
4748 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align);
4749 thissize = elt_size;
4750 for (unsigned int i = 1; i < VECTOR_CST_NELTS (exp); i++)
4752 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign);
4753 thissize += elt_size;
4755 break;
4757 default:
4758 gcc_unreachable ();
4760 break;
4762 case RECORD_TYPE:
4763 case UNION_TYPE:
4764 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4765 return output_constructor (exp, size, align, NULL);
4767 case ERROR_MARK:
4768 return 0;
4770 default:
4771 gcc_unreachable ();
4774 if (size > thissize)
4775 assemble_zeros (size - thissize);
4777 return size;
4781 /* Subroutine of output_constructor, used for computing the size of
4782 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4783 type with an unspecified upper bound. */
4785 static unsigned HOST_WIDE_INT
4786 array_size_for_constructor (tree val)
4788 tree max_index;
4789 unsigned HOST_WIDE_INT cnt;
4790 tree index, value, tmp;
4791 offset_int i;
4793 /* This code used to attempt to handle string constants that are not
4794 arrays of single-bytes, but nothing else does, so there's no point in
4795 doing it here. */
4796 if (TREE_CODE (val) == STRING_CST)
4797 return TREE_STRING_LENGTH (val);
4799 max_index = NULL_TREE;
4800 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
4802 if (TREE_CODE (index) == RANGE_EXPR)
4803 index = TREE_OPERAND (index, 1);
4804 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
4805 max_index = index;
4808 if (max_index == NULL_TREE)
4809 return 0;
4811 /* Compute the total number of array elements. */
4812 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
4813 i = wi::to_offset (max_index) - wi::to_offset (tmp) + 1;
4815 /* Multiply by the array element unit size to find number of bytes. */
4816 i *= wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
4818 gcc_assert (wi::fits_uhwi_p (i));
4819 return i.to_uhwi ();
4822 /* Other datastructures + helpers for output_constructor. */
4824 /* output_constructor local state to support interaction with helpers. */
4826 typedef struct {
4828 /* Received arguments. */
4829 tree exp; /* Constructor expression. */
4830 tree type; /* Type of constructor expression. */
4831 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */
4832 unsigned int align; /* Known initial alignment. */
4833 tree min_index; /* Lower bound if specified for an array. */
4835 /* Output processing state. */
4836 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */
4837 int byte; /* Part of a bitfield byte yet to be output. */
4838 int last_relative_index; /* Implicit or explicit index of the last
4839 array element output within a bitfield. */
4840 bool byte_buffer_in_use; /* Whether BYTE is in use. */
4842 /* Current element. */
4843 tree field; /* Current field decl in a record. */
4844 tree val; /* Current element value. */
4845 tree index; /* Current element index. */
4847 } oc_local_state;
4849 /* Helper for output_constructor. From the current LOCAL state, output a
4850 RANGE_EXPR element. */
4852 static void
4853 output_constructor_array_range (oc_local_state *local)
4855 unsigned HOST_WIDE_INT fieldsize
4856 = int_size_in_bytes (TREE_TYPE (local->type));
4858 HOST_WIDE_INT lo_index
4859 = tree_to_shwi (TREE_OPERAND (local->index, 0));
4860 HOST_WIDE_INT hi_index
4861 = tree_to_shwi (TREE_OPERAND (local->index, 1));
4862 HOST_WIDE_INT index;
4864 unsigned int align2
4865 = min_align (local->align, fieldsize * BITS_PER_UNIT);
4867 for (index = lo_index; index <= hi_index; index++)
4869 /* Output the element's initial value. */
4870 if (local->val == NULL_TREE)
4871 assemble_zeros (fieldsize);
4872 else
4873 fieldsize = output_constant (local->val, fieldsize, align2);
4875 /* Count its size. */
4876 local->total_bytes += fieldsize;
4880 /* Helper for output_constructor. From the current LOCAL state, output a
4881 field element that is not true bitfield or part of an outer one. */
4883 static void
4884 output_constructor_regular_field (oc_local_state *local)
4886 /* Field size and position. Since this structure is static, we know the
4887 positions are constant. */
4888 unsigned HOST_WIDE_INT fieldsize;
4889 HOST_WIDE_INT fieldpos;
4891 unsigned int align2;
4893 if (local->index != NULL_TREE)
4895 /* Perform the index calculation in modulo arithmetic but
4896 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
4897 but we are using an unsigned sizetype. */
4898 unsigned prec = TYPE_PRECISION (sizetype);
4899 offset_int idx = wi::sext (wi::to_offset (local->index)
4900 - wi::to_offset (local->min_index), prec);
4901 fieldpos = (idx * wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (local->val))))
4902 .to_short_addr ();
4904 else if (local->field != NULL_TREE)
4905 fieldpos = int_byte_position (local->field);
4906 else
4907 fieldpos = 0;
4909 /* Output any buffered-up bit-fields preceding this element. */
4910 if (local->byte_buffer_in_use)
4912 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4913 local->total_bytes++;
4914 local->byte_buffer_in_use = false;
4917 /* Advance to offset of this element.
4918 Note no alignment needed in an array, since that is guaranteed
4919 if each element has the proper size. */
4920 if ((local->field != NULL_TREE || local->index != NULL_TREE)
4921 && fieldpos > local->total_bytes)
4923 assemble_zeros (fieldpos - local->total_bytes);
4924 local->total_bytes = fieldpos;
4927 /* Find the alignment of this element. */
4928 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
4930 /* Determine size this element should occupy. */
4931 if (local->field)
4933 fieldsize = 0;
4935 /* If this is an array with an unspecified upper bound,
4936 the initializer determines the size. */
4937 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
4938 but we cannot do this until the deprecated support for
4939 initializing zero-length array members is removed. */
4940 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
4941 && TYPE_DOMAIN (TREE_TYPE (local->field))
4942 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field))))
4944 fieldsize = array_size_for_constructor (local->val);
4945 /* Given a non-empty initialization, this field had
4946 better be last. */
4947 gcc_assert (!fieldsize || !DECL_CHAIN (local->field));
4949 else
4950 fieldsize = tree_to_uhwi (DECL_SIZE_UNIT (local->field));
4952 else
4953 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
4955 /* Output the element's initial value. */
4956 if (local->val == NULL_TREE)
4957 assemble_zeros (fieldsize);
4958 else
4959 fieldsize = output_constant (local->val, fieldsize, align2);
4961 /* Count its size. */
4962 local->total_bytes += fieldsize;
4965 /* Helper for output_constructor. From the LOCAL state, output an element
4966 that is a true bitfield or part of an outer one. BIT_OFFSET is the offset
4967 from the start of a possibly ongoing outer byte buffer. */
4969 static void
4970 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
4972 /* Bit size of this element. */
4973 HOST_WIDE_INT ebitsize
4974 = (local->field
4975 ? tree_to_uhwi (DECL_SIZE (local->field))
4976 : tree_to_uhwi (TYPE_SIZE (TREE_TYPE (local->type))));
4978 /* Relative index of this element if this is an array component. */
4979 HOST_WIDE_INT relative_index
4980 = (!local->field
4981 ? (local->index
4982 ? (tree_to_shwi (local->index)
4983 - tree_to_shwi (local->min_index))
4984 : local->last_relative_index + 1)
4985 : 0);
4987 /* Bit position of this element from the start of the containing
4988 constructor. */
4989 HOST_WIDE_INT constructor_relative_ebitpos
4990 = (local->field
4991 ? int_bit_position (local->field)
4992 : ebitsize * relative_index);
4994 /* Bit position of this element from the start of a possibly ongoing
4995 outer byte buffer. */
4996 HOST_WIDE_INT byte_relative_ebitpos
4997 = bit_offset + constructor_relative_ebitpos;
4999 /* From the start of a possibly ongoing outer byte buffer, offsets to
5000 the first bit of this element and to the first bit past the end of
5001 this element. */
5002 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
5003 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
5005 local->last_relative_index = relative_index;
5007 if (local->val == NULL_TREE)
5008 local->val = integer_zero_node;
5010 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
5011 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
5012 local->val = TREE_OPERAND (local->val, 0);
5014 if (TREE_CODE (local->val) != INTEGER_CST
5015 && TREE_CODE (local->val) != CONSTRUCTOR)
5017 error ("invalid initial value for member %qE", DECL_NAME (local->field));
5018 return;
5021 /* If this field does not start in this (or next) byte, skip some bytes. */
5022 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5024 /* Output remnant of any bit field in previous bytes. */
5025 if (local->byte_buffer_in_use)
5027 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5028 local->total_bytes++;
5029 local->byte_buffer_in_use = false;
5032 /* If still not at proper byte, advance to there. */
5033 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5035 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
5036 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
5037 local->total_bytes = next_offset / BITS_PER_UNIT;
5041 /* Set up the buffer if necessary. */
5042 if (!local->byte_buffer_in_use)
5044 local->byte = 0;
5045 if (ebitsize > 0)
5046 local->byte_buffer_in_use = true;
5049 /* If this is nested constructor, recurse passing the bit offset and the
5050 pending data, then retrieve the new pending data afterwards. */
5051 if (TREE_CODE (local->val) == CONSTRUCTOR)
5053 oc_outer_state temp_state;
5054 temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5055 temp_state.byte = local->byte;
5056 local->total_bytes
5057 += output_constructor (local->val, 0, 0, &temp_state);
5058 local->byte = temp_state.byte;
5059 return;
5062 /* Otherwise, we must split the element into pieces that fall within
5063 separate bytes, and combine each byte with previous or following
5064 bit-fields. */
5065 while (next_offset < end_offset)
5067 int this_time;
5068 int shift;
5069 HOST_WIDE_INT value;
5070 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5071 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5073 /* Advance from byte to byte within this element when necessary. */
5074 while (next_byte != local->total_bytes)
5076 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5077 local->total_bytes++;
5078 local->byte = 0;
5081 /* Number of bits we can process at once (all part of the same byte). */
5082 this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5083 if (BYTES_BIG_ENDIAN)
5085 /* On big-endian machine, take the most significant bits
5086 first (of the bits that are significant)
5087 and put them into bytes from the most significant end. */
5088 shift = end_offset - next_offset - this_time;
5090 /* Don't try to take a bunch of bits that cross
5091 the word boundary in the INTEGER_CST. We can
5092 only select bits from the LOW or HIGH part
5093 not from both. */
5094 if ((shift / HOST_BITS_PER_WIDE_INT)
5095 != ((shift + this_time) / HOST_BITS_PER_WIDE_INT))
5096 this_time = (shift + this_time) & (HOST_BITS_PER_WIDE_INT - 1);
5098 /* Now get the bits from the appropriate constant word. */
5099 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5100 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5102 /* Get the result. This works only when:
5103 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5104 local->byte |= (((value >> shift)
5105 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5106 << (BITS_PER_UNIT - this_time - next_bit));
5108 else
5110 /* On little-endian machines,
5111 take first the least significant bits of the value
5112 and pack them starting at the least significant
5113 bits of the bytes. */
5114 shift = next_offset - byte_relative_ebitpos;
5116 /* Don't try to take a bunch of bits that cross
5117 the word boundary in the INTEGER_CST. We can
5118 only select bits from the LOW or HIGH part
5119 not from both. */
5120 if ((shift / HOST_BITS_PER_WIDE_INT)
5121 != ((shift + this_time) / HOST_BITS_PER_WIDE_INT))
5122 this_time = (HOST_BITS_PER_WIDE_INT - shift);
5124 /* Now get the bits from the appropriate constant word. */
5125 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5126 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5128 /* Get the result. This works only when:
5129 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5130 local->byte |= (((value >> shift)
5131 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5132 << next_bit);
5135 next_offset += this_time;
5136 local->byte_buffer_in_use = true;
5140 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5141 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5142 caller output state of relevance in recursive invocations. */
5144 static unsigned HOST_WIDE_INT
5145 output_constructor (tree exp, unsigned HOST_WIDE_INT size,
5146 unsigned int align, oc_outer_state *outer)
5148 unsigned HOST_WIDE_INT cnt;
5149 constructor_elt *ce;
5151 oc_local_state local;
5153 /* Setup our local state to communicate with helpers. */
5154 local.exp = exp;
5155 local.type = TREE_TYPE (exp);
5156 local.size = size;
5157 local.align = align;
5158 if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5159 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5160 else
5161 local.min_index = NULL_TREE;
5163 local.total_bytes = 0;
5164 local.byte_buffer_in_use = outer != NULL;
5165 local.byte = outer ? outer->byte : 0;
5166 local.last_relative_index = -1;
5168 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5170 /* As CE goes through the elements of the constant, FIELD goes through the
5171 structure fields if the constant is a structure. If the constant is a
5172 union, we override this by getting the field from the TREE_LIST element.
5173 But the constant could also be an array. Then FIELD is zero.
5175 There is always a maximum of one element in the chain LINK for unions
5176 (even if the initializer in a source program incorrectly contains
5177 more one). */
5179 if (TREE_CODE (local.type) == RECORD_TYPE)
5180 local.field = TYPE_FIELDS (local.type);
5181 else
5182 local.field = NULL_TREE;
5184 for (cnt = 0;
5185 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5186 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5188 local.val = ce->value;
5189 local.index = NULL_TREE;
5191 /* The element in a union constructor specifies the proper field
5192 or index. */
5193 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5194 local.field = ce->index;
5196 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5197 local.index = ce->index;
5199 if (local.field && flag_verbose_asm)
5200 fprintf (asm_out_file, "%s %s:\n",
5201 ASM_COMMENT_START,
5202 DECL_NAME (local.field)
5203 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5204 : "<anonymous>");
5206 /* Eliminate the marker that makes a cast not be an lvalue. */
5207 if (local.val != NULL_TREE)
5208 STRIP_NOPS (local.val);
5210 /* Output the current element, using the appropriate helper ... */
5212 /* For an array slice not part of an outer bitfield. */
5213 if (!outer
5214 && local.index != NULL_TREE
5215 && TREE_CODE (local.index) == RANGE_EXPR)
5216 output_constructor_array_range (&local);
5218 /* For a field that is neither a true bitfield nor part of an outer one,
5219 known to be at least byte aligned and multiple-of-bytes long. */
5220 else if (!outer
5221 && (local.field == NULL_TREE
5222 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5223 output_constructor_regular_field (&local);
5225 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5226 supported for scalar fields, so we may need to convert first. */
5227 else
5229 if (TREE_CODE (local.val) == REAL_CST)
5230 local.val
5231 = fold_unary (VIEW_CONVERT_EXPR,
5232 build_nonstandard_integer_type
5233 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5234 local.val);
5235 output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5239 /* If we are not at toplevel, save the pending data for our caller.
5240 Otherwise output the pending data and padding zeros as needed. */
5241 if (outer)
5242 outer->byte = local.byte;
5243 else
5245 if (local.byte_buffer_in_use)
5247 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5248 local.total_bytes++;
5251 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5253 assemble_zeros (local.size - local.total_bytes);
5254 local.total_bytes = local.size;
5258 return local.total_bytes;
5261 /* Mark DECL as weak. */
5263 static void
5264 mark_weak (tree decl)
5266 DECL_WEAK (decl) = 1;
5268 if (DECL_RTL_SET_P (decl)
5269 && MEM_P (DECL_RTL (decl))
5270 && XEXP (DECL_RTL (decl), 0)
5271 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5272 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5275 /* Merge weak status between NEWDECL and OLDDECL. */
5277 void
5278 merge_weak (tree newdecl, tree olddecl)
5280 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5282 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5284 tree *pwd;
5285 /* We put the NEWDECL on the weak_decls list at some point
5286 and OLDDECL as well. Keep just OLDDECL on the list. */
5287 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5288 if (TREE_VALUE (*pwd) == newdecl)
5290 *pwd = TREE_CHAIN (*pwd);
5291 break;
5294 return;
5297 if (DECL_WEAK (newdecl))
5299 tree wd;
5301 /* NEWDECL is weak, but OLDDECL is not. */
5303 /* If we already output the OLDDECL, we're in trouble; we can't
5304 go back and make it weak. This should never happen in
5305 unit-at-a-time compilation. */
5306 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5308 /* If we've already generated rtl referencing OLDDECL, we may
5309 have done so in a way that will not function properly with
5310 a weak symbol. Again in unit-at-a-time this should be
5311 impossible. */
5312 gcc_assert (!TREE_USED (olddecl)
5313 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5315 if (TARGET_SUPPORTS_WEAK)
5317 /* We put the NEWDECL on the weak_decls list at some point.
5318 Replace it with the OLDDECL. */
5319 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5320 if (TREE_VALUE (wd) == newdecl)
5322 TREE_VALUE (wd) = olddecl;
5323 break;
5325 /* We may not find the entry on the list. If NEWDECL is a
5326 weak alias, then we will have already called
5327 globalize_decl to remove the entry; in that case, we do
5328 not need to do anything. */
5331 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5332 mark_weak (olddecl);
5334 else
5335 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5336 weak. Just update NEWDECL to indicate that it's weak too. */
5337 mark_weak (newdecl);
5340 /* Declare DECL to be a weak symbol. */
5342 void
5343 declare_weak (tree decl)
5345 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5346 if (! TREE_PUBLIC (decl))
5347 error ("weak declaration of %q+D must be public", decl);
5348 else if (!TARGET_SUPPORTS_WEAK)
5349 warning (0, "weak declaration of %q+D not supported", decl);
5351 mark_weak (decl);
5352 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5353 DECL_ATTRIBUTES (decl)
5354 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5357 static void
5358 weak_finish_1 (tree decl)
5360 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5361 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5362 #endif
5364 if (! TREE_USED (decl))
5365 return;
5367 #ifdef ASM_WEAKEN_DECL
5368 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5369 #else
5370 #ifdef ASM_WEAKEN_LABEL
5371 ASM_WEAKEN_LABEL (asm_out_file, name);
5372 #else
5373 #ifdef ASM_OUTPUT_WEAK_ALIAS
5375 static bool warn_once = 0;
5376 if (! warn_once)
5378 warning (0, "only weak aliases are supported in this configuration");
5379 warn_once = 1;
5381 return;
5383 #endif
5384 #endif
5385 #endif
5388 /* Fiven an assembly name, find the decl it is associated with. */
5389 static tree
5390 find_decl (tree target)
5392 symtab_node *node = symtab_node_for_asm (target);
5393 if (node)
5394 return node->decl;
5395 return NULL_TREE;
5398 /* This TREE_LIST contains weakref targets. */
5400 static GTY(()) tree weakref_targets;
5402 /* Emit any pending weak declarations. */
5404 void
5405 weak_finish (void)
5407 tree t;
5409 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5411 tree alias_decl = TREE_PURPOSE (t);
5412 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5414 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5415 /* Remove alias_decl from the weak list, but leave entries for
5416 the target alone. */
5417 target = NULL_TREE;
5418 #ifndef ASM_OUTPUT_WEAKREF
5419 else if (! TREE_SYMBOL_REFERENCED (target))
5421 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5422 defined, otherwise we and weak_finish_1 would use
5423 different macros. */
5424 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5425 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5426 # else
5427 tree decl = find_decl (target);
5429 if (! decl)
5431 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5432 TREE_CODE (alias_decl), target,
5433 TREE_TYPE (alias_decl));
5435 DECL_EXTERNAL (decl) = 1;
5436 TREE_PUBLIC (decl) = 1;
5437 DECL_ARTIFICIAL (decl) = 1;
5438 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5439 TREE_USED (decl) = 1;
5442 weak_finish_1 (decl);
5443 # endif
5445 #endif
5448 tree *p;
5449 tree t2;
5451 /* Remove the alias and the target from the pending weak list
5452 so that we do not emit any .weak directives for the former,
5453 nor multiple .weak directives for the latter. */
5454 for (p = &weak_decls; (t2 = *p) ; )
5456 if (TREE_VALUE (t2) == alias_decl
5457 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5458 *p = TREE_CHAIN (t2);
5459 else
5460 p = &TREE_CHAIN (t2);
5463 /* Remove other weakrefs to the same target, to speed things up. */
5464 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5466 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5467 *p = TREE_CHAIN (t2);
5468 else
5469 p = &TREE_CHAIN (t2);
5474 for (t = weak_decls; t; t = TREE_CHAIN (t))
5476 tree decl = TREE_VALUE (t);
5478 weak_finish_1 (decl);
5482 /* Emit the assembly bits to indicate that DECL is globally visible. */
5484 static void
5485 globalize_decl (tree decl)
5488 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5489 if (DECL_WEAK (decl))
5491 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5492 tree *p, t;
5494 #ifdef ASM_WEAKEN_DECL
5495 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5496 #else
5497 ASM_WEAKEN_LABEL (asm_out_file, name);
5498 #endif
5500 /* Remove this function from the pending weak list so that
5501 we do not emit multiple .weak directives for it. */
5502 for (p = &weak_decls; (t = *p) ; )
5504 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5505 *p = TREE_CHAIN (t);
5506 else
5507 p = &TREE_CHAIN (t);
5510 /* Remove weakrefs to the same target from the pending weakref
5511 list, for the same reason. */
5512 for (p = &weakref_targets; (t = *p) ; )
5514 if (DECL_ASSEMBLER_NAME (decl)
5515 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5516 *p = TREE_CHAIN (t);
5517 else
5518 p = &TREE_CHAIN (t);
5521 return;
5523 #endif
5525 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5528 vec<alias_pair, va_gc> *alias_pairs;
5530 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5531 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5532 tree node is DECL to have the value of the tree node TARGET. */
5534 void
5535 do_assemble_alias (tree decl, tree target)
5537 /* Emulated TLS had better not get this var. */
5538 gcc_assert (!(!targetm.have_tls
5539 && TREE_CODE (decl) == VAR_DECL
5540 && DECL_THREAD_LOCAL_P (decl)));
5542 if (TREE_ASM_WRITTEN (decl))
5543 return;
5545 /* We must force creation of DECL_RTL for debug info generation, even though
5546 we don't use it here. */
5547 make_decl_rtl (decl);
5549 TREE_ASM_WRITTEN (decl) = 1;
5550 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5552 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5554 ultimate_transparent_alias_target (&target);
5556 if (!TREE_SYMBOL_REFERENCED (target))
5557 weakref_targets = tree_cons (decl, target, weakref_targets);
5559 #ifdef ASM_OUTPUT_WEAKREF
5560 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5561 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5562 IDENTIFIER_POINTER (target));
5563 #else
5564 if (!TARGET_SUPPORTS_WEAK)
5566 error_at (DECL_SOURCE_LOCATION (decl),
5567 "weakref is not supported in this configuration");
5568 return;
5570 #endif
5571 return;
5574 #ifdef ASM_OUTPUT_DEF
5575 /* Make name accessible from other files, if appropriate. */
5577 if (TREE_PUBLIC (decl))
5579 globalize_decl (decl);
5580 maybe_assemble_visibility (decl);
5582 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5584 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5585 if (targetm.has_ifunc_p ())
5586 ASM_OUTPUT_TYPE_DIRECTIVE
5587 (asm_out_file, IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5588 IFUNC_ASM_TYPE);
5589 else
5590 #endif
5591 error_at (DECL_SOURCE_LOCATION (decl),
5592 "ifunc is not supported on this target");
5595 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5596 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5597 # else
5598 ASM_OUTPUT_DEF (asm_out_file,
5599 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5600 IDENTIFIER_POINTER (target));
5601 # endif
5602 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5604 const char *name;
5605 tree *p, t;
5607 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5608 # ifdef ASM_WEAKEN_DECL
5609 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5610 # else
5611 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5612 # endif
5613 /* Remove this function from the pending weak list so that
5614 we do not emit multiple .weak directives for it. */
5615 for (p = &weak_decls; (t = *p) ; )
5616 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5617 *p = TREE_CHAIN (t);
5618 else
5619 p = &TREE_CHAIN (t);
5621 /* Remove weakrefs to the same target from the pending weakref
5622 list, for the same reason. */
5623 for (p = &weakref_targets; (t = *p) ; )
5625 if (DECL_ASSEMBLER_NAME (decl)
5626 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5627 *p = TREE_CHAIN (t);
5628 else
5629 p = &TREE_CHAIN (t);
5632 #endif
5635 /* Emit an assembler directive to make the symbol for DECL an alias to
5636 the symbol for TARGET. */
5638 void
5639 assemble_alias (tree decl, tree target)
5641 tree target_decl;
5643 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5645 tree alias = DECL_ASSEMBLER_NAME (decl);
5647 ultimate_transparent_alias_target (&target);
5649 if (alias == target)
5650 error ("weakref %q+D ultimately targets itself", decl);
5651 if (TREE_PUBLIC (decl))
5652 error ("weakref %q+D must have static linkage", decl);
5654 else
5656 #if !defined (ASM_OUTPUT_DEF)
5657 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5658 error_at (DECL_SOURCE_LOCATION (decl),
5659 "alias definitions not supported in this configuration");
5660 TREE_ASM_WRITTEN (decl) = 1;
5661 return;
5662 # else
5663 if (!DECL_WEAK (decl))
5665 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5666 error_at (DECL_SOURCE_LOCATION (decl),
5667 "ifunc is not supported in this configuration");
5668 else
5669 error_at (DECL_SOURCE_LOCATION (decl),
5670 "only weak aliases are supported in this configuration");
5671 TREE_ASM_WRITTEN (decl) = 1;
5672 return;
5674 # endif
5675 #endif
5677 TREE_USED (decl) = 1;
5679 /* Allow aliases to aliases. */
5680 if (TREE_CODE (decl) == FUNCTION_DECL)
5681 cgraph_get_create_node (decl)->alias = true;
5682 else
5683 varpool_node_for_decl (decl)->alias = true;
5685 /* If the target has already been emitted, we don't have to queue the
5686 alias. This saves a tad of memory. */
5687 if (cgraph_global_info_ready)
5688 target_decl = find_decl (target);
5689 else
5690 target_decl= NULL;
5691 if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5692 || cgraph_state >= CGRAPH_STATE_EXPANSION)
5693 do_assemble_alias (decl, target);
5694 else
5696 alias_pair p = {decl, target};
5697 vec_safe_push (alias_pairs, p);
5701 /* Record and output a table of translations from original function
5702 to its transaction aware clone. Note that tm_pure functions are
5703 considered to be their own clone. */
5705 static GTY((if_marked ("tree_map_marked_p"), param_is (struct tree_map)))
5706 htab_t tm_clone_hash;
5708 void
5709 record_tm_clone_pair (tree o, tree n)
5711 struct tree_map **slot, *h;
5713 if (tm_clone_hash == NULL)
5714 tm_clone_hash = htab_create_ggc (32, tree_map_hash, tree_map_eq, 0);
5716 h = ggc_alloc<tree_map> ();
5717 h->hash = htab_hash_pointer (o);
5718 h->base.from = o;
5719 h->to = n;
5721 slot = (struct tree_map **)
5722 htab_find_slot_with_hash (tm_clone_hash, h, h->hash, INSERT);
5723 *slot = h;
5726 tree
5727 get_tm_clone_pair (tree o)
5729 if (tm_clone_hash)
5731 struct tree_map *h, in;
5733 in.base.from = o;
5734 in.hash = htab_hash_pointer (o);
5735 h = (struct tree_map *) htab_find_with_hash (tm_clone_hash,
5736 &in, in.hash);
5737 if (h)
5738 return h->to;
5740 return NULL_TREE;
5743 typedef struct tm_alias_pair
5745 unsigned int uid;
5746 tree from;
5747 tree to;
5748 } tm_alias_pair;
5751 /* Helper function for finish_tm_clone_pairs. Dump a hash table entry
5752 into a VEC in INFO. */
5754 static int
5755 dump_tm_clone_to_vec (void **slot, void *info)
5757 struct tree_map *map = (struct tree_map *) *slot;
5758 vec<tm_alias_pair> *tm_alias_pairs = (vec<tm_alias_pair> *) info;
5759 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
5760 tm_alias_pairs->safe_push (p);
5761 return 1;
5764 /* Dump the actual pairs to the .tm_clone_table section. */
5766 static void
5767 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
5769 unsigned i;
5770 tm_alias_pair *p;
5771 bool switched = false;
5773 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
5775 tree src = p->from;
5776 tree dst = p->to;
5777 struct cgraph_node *src_n = cgraph_get_node (src);
5778 struct cgraph_node *dst_n = cgraph_get_node (dst);
5780 /* The function ipa_tm_create_version() marks the clone as needed if
5781 the original function was needed. But we also mark the clone as
5782 needed if we ever called the clone indirectly through
5783 TM_GETTMCLONE. If neither of these are true, we didn't generate
5784 a clone, and we didn't call it indirectly... no sense keeping it
5785 in the clone table. */
5786 if (!dst_n || !dst_n->definition)
5787 continue;
5789 /* This covers the case where we have optimized the original
5790 function away, and only access the transactional clone. */
5791 if (!src_n || !src_n->definition)
5792 continue;
5794 if (!switched)
5796 switch_to_section (targetm.asm_out.tm_clone_table_section ());
5797 assemble_align (POINTER_SIZE);
5798 switched = true;
5801 assemble_integer (XEXP (DECL_RTL (src), 0),
5802 POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
5803 assemble_integer (XEXP (DECL_RTL (dst), 0),
5804 POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
5808 /* Provide a default for the tm_clone_table section. */
5810 section *
5811 default_clone_table_section (void)
5813 return get_named_section (NULL, ".tm_clone_table", 3);
5816 /* Helper comparison function for qsorting by the DECL_UID stored in
5817 alias_pair->emitted_diags. */
5819 static int
5820 tm_alias_pair_cmp (const void *x, const void *y)
5822 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
5823 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
5824 if (p1->uid < p2->uid)
5825 return -1;
5826 if (p1->uid > p2->uid)
5827 return 1;
5828 return 0;
5831 void
5832 finish_tm_clone_pairs (void)
5834 vec<tm_alias_pair> tm_alias_pairs = vNULL;
5836 if (tm_clone_hash == NULL)
5837 return;
5839 /* We need a determenistic order for the .tm_clone_table, otherwise
5840 we will get bootstrap comparison failures, so dump the hash table
5841 to a vector, sort it, and dump the vector. */
5843 /* Dump the hashtable to a vector. */
5844 htab_traverse_noresize (tm_clone_hash, dump_tm_clone_to_vec,
5845 (void *) &tm_alias_pairs);
5846 /* Sort it. */
5847 tm_alias_pairs.qsort (tm_alias_pair_cmp);
5849 /* Dump it. */
5850 dump_tm_clone_pairs (tm_alias_pairs);
5852 htab_delete (tm_clone_hash);
5853 tm_clone_hash = NULL;
5854 tm_alias_pairs.release ();
5858 /* Emit an assembler directive to set symbol for DECL visibility to
5859 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
5861 void
5862 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
5863 int vis ATTRIBUTE_UNUSED)
5865 #ifdef HAVE_GAS_HIDDEN
5866 static const char * const visibility_types[] = {
5867 NULL, "protected", "hidden", "internal"
5870 const char *name, *type;
5872 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5873 type = visibility_types[vis];
5875 fprintf (asm_out_file, "\t.%s\t", type);
5876 assemble_name (asm_out_file, name);
5877 fprintf (asm_out_file, "\n");
5878 #else
5879 if (!DECL_ARTIFICIAL (decl))
5880 warning (OPT_Wattributes, "visibility attribute not supported "
5881 "in this configuration; ignored");
5882 #endif
5885 /* A helper function to call assemble_visibility when needed for a decl. */
5888 maybe_assemble_visibility (tree decl)
5890 enum symbol_visibility vis = DECL_VISIBILITY (decl);
5892 if (vis != VISIBILITY_DEFAULT)
5894 targetm.asm_out.assemble_visibility (decl, vis);
5895 return 1;
5897 else
5898 return 0;
5901 /* Returns 1 if the target configuration supports defining public symbols
5902 so that one of them will be chosen at link time instead of generating a
5903 multiply-defined symbol error, whether through the use of weak symbols or
5904 a target-specific mechanism for having duplicates discarded. */
5907 supports_one_only (void)
5909 if (SUPPORTS_ONE_ONLY)
5910 return 1;
5911 return TARGET_SUPPORTS_WEAK;
5914 /* Set up DECL as a public symbol that can be defined in multiple
5915 translation units without generating a linker error. */
5917 void
5918 make_decl_one_only (tree decl, tree comdat_group)
5920 gcc_assert (TREE_CODE (decl) == VAR_DECL
5921 || TREE_CODE (decl) == FUNCTION_DECL);
5923 TREE_PUBLIC (decl) = 1;
5925 if (SUPPORTS_ONE_ONLY)
5927 #ifdef MAKE_DECL_ONE_ONLY
5928 MAKE_DECL_ONE_ONLY (decl);
5929 #endif
5930 DECL_COMDAT_GROUP (decl) = comdat_group;
5932 else if (TREE_CODE (decl) == VAR_DECL
5933 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node))
5934 DECL_COMMON (decl) = 1;
5935 else
5937 gcc_assert (TARGET_SUPPORTS_WEAK);
5938 DECL_WEAK (decl) = 1;
5942 void
5943 init_varasm_once (void)
5945 section_htab = htab_create_ggc (31, section_entry_hash,
5946 section_entry_eq, NULL);
5947 object_block_htab = htab_create_ggc (31, object_block_entry_hash,
5948 object_block_entry_eq, NULL);
5949 const_desc_htab = htab_create_ggc (1009, const_desc_hash,
5950 const_desc_eq, NULL);
5952 const_alias_set = new_alias_set ();
5953 shared_constant_pool = create_constant_pool ();
5955 #ifdef TEXT_SECTION_ASM_OP
5956 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
5957 TEXT_SECTION_ASM_OP);
5958 #endif
5960 #ifdef DATA_SECTION_ASM_OP
5961 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5962 DATA_SECTION_ASM_OP);
5963 #endif
5965 #ifdef SDATA_SECTION_ASM_OP
5966 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5967 SDATA_SECTION_ASM_OP);
5968 #endif
5970 #ifdef READONLY_DATA_SECTION_ASM_OP
5971 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
5972 READONLY_DATA_SECTION_ASM_OP);
5973 #endif
5975 #ifdef CTORS_SECTION_ASM_OP
5976 ctors_section = get_unnamed_section (0, output_section_asm_op,
5977 CTORS_SECTION_ASM_OP);
5978 #endif
5980 #ifdef DTORS_SECTION_ASM_OP
5981 dtors_section = get_unnamed_section (0, output_section_asm_op,
5982 DTORS_SECTION_ASM_OP);
5983 #endif
5985 #ifdef BSS_SECTION_ASM_OP
5986 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5987 output_section_asm_op,
5988 BSS_SECTION_ASM_OP);
5989 #endif
5991 #ifdef SBSS_SECTION_ASM_OP
5992 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5993 output_section_asm_op,
5994 SBSS_SECTION_ASM_OP);
5995 #endif
5997 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5998 | SECTION_COMMON, emit_tls_common);
5999 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6000 | SECTION_COMMON, emit_local);
6001 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6002 | SECTION_COMMON, emit_common);
6004 #if defined ASM_OUTPUT_ALIGNED_BSS
6005 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
6006 emit_bss);
6007 #endif
6009 targetm.asm_out.init_sections ();
6011 if (readonly_data_section == NULL)
6012 readonly_data_section = text_section;
6014 #ifdef ASM_OUTPUT_EXTERNAL
6015 pending_assemble_externals_set = pointer_set_create ();
6016 #endif
6019 enum tls_model
6020 decl_default_tls_model (const_tree decl)
6022 enum tls_model kind;
6023 bool is_local;
6025 is_local = targetm.binds_local_p (decl);
6026 if (!flag_shlib)
6028 if (is_local)
6029 kind = TLS_MODEL_LOCAL_EXEC;
6030 else
6031 kind = TLS_MODEL_INITIAL_EXEC;
6034 /* Local dynamic is inefficient when we're not combining the
6035 parts of the address. */
6036 else if (optimize && is_local)
6037 kind = TLS_MODEL_LOCAL_DYNAMIC;
6038 else
6039 kind = TLS_MODEL_GLOBAL_DYNAMIC;
6040 if (kind < flag_tls_default)
6041 kind = flag_tls_default;
6043 return kind;
6046 /* Select a set of attributes for section NAME based on the properties
6047 of DECL and whether or not RELOC indicates that DECL's initializer
6048 might contain runtime relocations.
6050 We make the section read-only and executable for a function decl,
6051 read-only for a const data decl, and writable for a non-const data decl. */
6053 unsigned int
6054 default_section_type_flags (tree decl, const char *name, int reloc)
6056 unsigned int flags;
6058 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6059 flags = SECTION_CODE;
6060 else if (decl)
6062 enum section_category category
6063 = categorize_decl_for_section (decl, reloc);
6064 if (decl_readonly_section_1 (category))
6065 flags = 0;
6066 else if (category == SECCAT_DATA_REL_RO
6067 || category == SECCAT_DATA_REL_RO_LOCAL)
6068 flags = SECTION_WRITE | SECTION_RELRO;
6069 else
6070 flags = SECTION_WRITE;
6072 else
6074 flags = SECTION_WRITE;
6075 if (strcmp (name, ".data.rel.ro") == 0
6076 || strcmp (name, ".data.rel.ro.local") == 0)
6077 flags |= SECTION_RELRO;
6080 if (decl && DECL_P (decl) && DECL_COMDAT_GROUP (decl))
6081 flags |= SECTION_LINKONCE;
6083 if (strcmp (name, ".vtable_map_vars") == 0)
6084 flags |= SECTION_LINKONCE;
6086 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6087 flags |= SECTION_TLS | SECTION_WRITE;
6089 if (strcmp (name, ".bss") == 0
6090 || strncmp (name, ".bss.", 5) == 0
6091 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6092 || strcmp (name, ".sbss") == 0
6093 || strncmp (name, ".sbss.", 6) == 0
6094 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6095 flags |= SECTION_BSS;
6097 if (strcmp (name, ".tdata") == 0
6098 || strncmp (name, ".tdata.", 7) == 0
6099 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6100 flags |= SECTION_TLS;
6102 if (strcmp (name, ".tbss") == 0
6103 || strncmp (name, ".tbss.", 6) == 0
6104 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6105 flags |= SECTION_TLS | SECTION_BSS;
6107 /* These three sections have special ELF types. They are neither
6108 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
6109 want to print a section type (@progbits or @nobits). If someone
6110 is silly enough to emit code or TLS variables to one of these
6111 sections, then don't handle them specially. */
6112 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6113 && (strcmp (name, ".init_array") == 0
6114 || strcmp (name, ".fini_array") == 0
6115 || strcmp (name, ".preinit_array") == 0))
6116 flags |= SECTION_NOTYPE;
6118 return flags;
6121 /* Return true if the target supports some form of global BSS,
6122 either through bss_noswitch_section, or by selecting a BSS
6123 section in TARGET_ASM_SELECT_SECTION. */
6125 bool
6126 have_global_bss_p (void)
6128 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6131 /* Output assembly to switch to section NAME with attribute FLAGS.
6132 Four variants for common object file formats. */
6134 void
6135 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6136 unsigned int flags ATTRIBUTE_UNUSED,
6137 tree decl ATTRIBUTE_UNUSED)
6139 /* Some object formats don't support named sections at all. The
6140 front-end should already have flagged this as an error. */
6141 gcc_unreachable ();
6144 #ifndef TLS_SECTION_ASM_FLAG
6145 #define TLS_SECTION_ASM_FLAG 'T'
6146 #endif
6148 void
6149 default_elf_asm_named_section (const char *name, unsigned int flags,
6150 tree decl ATTRIBUTE_UNUSED)
6152 char flagchars[10], *f = flagchars;
6154 /* If we have already declared this section, we can use an
6155 abbreviated form to switch back to it -- unless this section is
6156 part of a COMDAT groups, in which case GAS requires the full
6157 declaration every time. */
6158 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6159 && (flags & SECTION_DECLARED))
6161 fprintf (asm_out_file, "\t.section\t%s\n", name);
6162 return;
6165 if (!(flags & SECTION_DEBUG))
6166 *f++ = 'a';
6167 if (flags & SECTION_EXCLUDE)
6168 *f++ = 'e';
6169 if (flags & SECTION_WRITE)
6170 *f++ = 'w';
6171 if (flags & SECTION_CODE)
6172 *f++ = 'x';
6173 if (flags & SECTION_SMALL)
6174 *f++ = 's';
6175 if (flags & SECTION_MERGE)
6176 *f++ = 'M';
6177 if (flags & SECTION_STRINGS)
6178 *f++ = 'S';
6179 if (flags & SECTION_TLS)
6180 *f++ = TLS_SECTION_ASM_FLAG;
6181 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6182 *f++ = 'G';
6183 *f = '\0';
6185 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6187 if (!(flags & SECTION_NOTYPE))
6189 const char *type;
6190 const char *format;
6192 if (flags & SECTION_BSS)
6193 type = "nobits";
6194 else
6195 type = "progbits";
6197 format = ",@%s";
6198 /* On platforms that use "@" as the assembly comment character,
6199 use "%" instead. */
6200 if (strcmp (ASM_COMMENT_START, "@") == 0)
6201 format = ",%%%s";
6202 fprintf (asm_out_file, format, type);
6204 if (flags & SECTION_ENTSIZE)
6205 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6206 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6208 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6209 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6210 else
6211 fprintf (asm_out_file, ",%s,comdat",
6212 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6216 putc ('\n', asm_out_file);
6219 void
6220 default_coff_asm_named_section (const char *name, unsigned int flags,
6221 tree decl ATTRIBUTE_UNUSED)
6223 char flagchars[8], *f = flagchars;
6225 if (flags & SECTION_WRITE)
6226 *f++ = 'w';
6227 if (flags & SECTION_CODE)
6228 *f++ = 'x';
6229 *f = '\0';
6231 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6234 void
6235 default_pe_asm_named_section (const char *name, unsigned int flags,
6236 tree decl)
6238 default_coff_asm_named_section (name, flags, decl);
6240 if (flags & SECTION_LINKONCE)
6242 /* Functions may have been compiled at various levels of
6243 optimization so we can't use `same_size' here.
6244 Instead, have the linker pick one. */
6245 fprintf (asm_out_file, "\t.linkonce %s\n",
6246 (flags & SECTION_CODE ? "discard" : "same_size"));
6250 /* The lame default section selector. */
6252 section *
6253 default_select_section (tree decl, int reloc,
6254 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6256 if (DECL_P (decl))
6258 if (decl_readonly_section (decl, reloc))
6259 return readonly_data_section;
6261 else if (TREE_CODE (decl) == CONSTRUCTOR)
6263 if (! ((flag_pic && reloc)
6264 || !TREE_READONLY (decl)
6265 || TREE_SIDE_EFFECTS (decl)
6266 || !TREE_CONSTANT (decl)))
6267 return readonly_data_section;
6269 else if (TREE_CODE (decl) == STRING_CST)
6270 return readonly_data_section;
6271 else if (! (flag_pic && reloc))
6272 return readonly_data_section;
6274 return data_section;
6277 enum section_category
6278 categorize_decl_for_section (const_tree decl, int reloc)
6280 enum section_category ret;
6282 if (TREE_CODE (decl) == FUNCTION_DECL)
6283 return SECCAT_TEXT;
6284 else if (TREE_CODE (decl) == STRING_CST)
6286 if ((flag_sanitize & SANITIZE_ADDRESS)
6287 && asan_protect_global (CONST_CAST_TREE (decl)))
6288 /* or !flag_merge_constants */
6289 return SECCAT_RODATA;
6290 else
6291 return SECCAT_RODATA_MERGE_STR;
6293 else if (TREE_CODE (decl) == VAR_DECL)
6295 if (bss_initializer_p (decl))
6296 ret = SECCAT_BSS;
6297 else if (! TREE_READONLY (decl)
6298 || TREE_SIDE_EFFECTS (decl)
6299 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
6301 /* Here the reloc_rw_mask is not testing whether the section should
6302 be read-only or not, but whether the dynamic link will have to
6303 do something. If so, we wish to segregate the data in order to
6304 minimize cache misses inside the dynamic linker. */
6305 if (reloc & targetm.asm_out.reloc_rw_mask ())
6306 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6307 else
6308 ret = SECCAT_DATA;
6310 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6311 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6312 else if (reloc || flag_merge_constants < 2
6313 || ((flag_sanitize & SANITIZE_ADDRESS)
6314 && asan_protect_global (CONST_CAST_TREE (decl))))
6315 /* C and C++ don't allow different variables to share the same
6316 location. -fmerge-all-constants allows even that (at the
6317 expense of not conforming). */
6318 ret = SECCAT_RODATA;
6319 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6320 ret = SECCAT_RODATA_MERGE_STR_INIT;
6321 else
6322 ret = SECCAT_RODATA_MERGE_CONST;
6324 else if (TREE_CODE (decl) == CONSTRUCTOR)
6326 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6327 || TREE_SIDE_EFFECTS (decl)
6328 || ! TREE_CONSTANT (decl))
6329 ret = SECCAT_DATA;
6330 else
6331 ret = SECCAT_RODATA;
6333 else
6334 ret = SECCAT_RODATA;
6336 /* There are no read-only thread-local sections. */
6337 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6339 /* Note that this would be *just* SECCAT_BSS, except that there's
6340 no concept of a read-only thread-local-data section. */
6341 if (ret == SECCAT_BSS
6342 || (flag_zero_initialized_in_bss
6343 && initializer_zerop (DECL_INITIAL (decl))))
6344 ret = SECCAT_TBSS;
6345 else
6346 ret = SECCAT_TDATA;
6349 /* If the target uses small data sections, select it. */
6350 else if (targetm.in_small_data_p (decl))
6352 if (ret == SECCAT_BSS)
6353 ret = SECCAT_SBSS;
6354 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6355 ret = SECCAT_SRODATA;
6356 else
6357 ret = SECCAT_SDATA;
6360 return ret;
6363 static bool
6364 decl_readonly_section_1 (enum section_category category)
6366 switch (category)
6368 case SECCAT_RODATA:
6369 case SECCAT_RODATA_MERGE_STR:
6370 case SECCAT_RODATA_MERGE_STR_INIT:
6371 case SECCAT_RODATA_MERGE_CONST:
6372 case SECCAT_SRODATA:
6373 return true;
6374 default:
6375 return false;
6379 bool
6380 decl_readonly_section (const_tree decl, int reloc)
6382 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6385 /* Select a section based on the above categorization. */
6387 section *
6388 default_elf_select_section (tree decl, int reloc,
6389 unsigned HOST_WIDE_INT align)
6391 const char *sname;
6392 switch (categorize_decl_for_section (decl, reloc))
6394 case SECCAT_TEXT:
6395 /* We're not supposed to be called on FUNCTION_DECLs. */
6396 gcc_unreachable ();
6397 case SECCAT_RODATA:
6398 return readonly_data_section;
6399 case SECCAT_RODATA_MERGE_STR:
6400 return mergeable_string_section (decl, align, 0);
6401 case SECCAT_RODATA_MERGE_STR_INIT:
6402 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6403 case SECCAT_RODATA_MERGE_CONST:
6404 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6405 case SECCAT_SRODATA:
6406 sname = ".sdata2";
6407 break;
6408 case SECCAT_DATA:
6409 return data_section;
6410 case SECCAT_DATA_REL:
6411 sname = ".data.rel";
6412 break;
6413 case SECCAT_DATA_REL_LOCAL:
6414 sname = ".data.rel.local";
6415 break;
6416 case SECCAT_DATA_REL_RO:
6417 sname = ".data.rel.ro";
6418 break;
6419 case SECCAT_DATA_REL_RO_LOCAL:
6420 sname = ".data.rel.ro.local";
6421 break;
6422 case SECCAT_SDATA:
6423 sname = ".sdata";
6424 break;
6425 case SECCAT_TDATA:
6426 sname = ".tdata";
6427 break;
6428 case SECCAT_BSS:
6429 if (bss_section)
6430 return bss_section;
6431 sname = ".bss";
6432 break;
6433 case SECCAT_SBSS:
6434 sname = ".sbss";
6435 break;
6436 case SECCAT_TBSS:
6437 sname = ".tbss";
6438 break;
6439 default:
6440 gcc_unreachable ();
6443 return get_named_section (decl, sname, reloc);
6446 /* Construct a unique section name based on the decl name and the
6447 categorization performed above. */
6449 void
6450 default_unique_section (tree decl, int reloc)
6452 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6453 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6454 const char *prefix, *name, *linkonce;
6455 char *string;
6457 switch (categorize_decl_for_section (decl, reloc))
6459 case SECCAT_TEXT:
6460 prefix = one_only ? ".t" : ".text";
6461 break;
6462 case SECCAT_RODATA:
6463 case SECCAT_RODATA_MERGE_STR:
6464 case SECCAT_RODATA_MERGE_STR_INIT:
6465 case SECCAT_RODATA_MERGE_CONST:
6466 prefix = one_only ? ".r" : ".rodata";
6467 break;
6468 case SECCAT_SRODATA:
6469 prefix = one_only ? ".s2" : ".sdata2";
6470 break;
6471 case SECCAT_DATA:
6472 prefix = one_only ? ".d" : ".data";
6473 break;
6474 case SECCAT_DATA_REL:
6475 prefix = one_only ? ".d.rel" : ".data.rel";
6476 break;
6477 case SECCAT_DATA_REL_LOCAL:
6478 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6479 break;
6480 case SECCAT_DATA_REL_RO:
6481 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6482 break;
6483 case SECCAT_DATA_REL_RO_LOCAL:
6484 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6485 break;
6486 case SECCAT_SDATA:
6487 prefix = one_only ? ".s" : ".sdata";
6488 break;
6489 case SECCAT_BSS:
6490 prefix = one_only ? ".b" : ".bss";
6491 break;
6492 case SECCAT_SBSS:
6493 prefix = one_only ? ".sb" : ".sbss";
6494 break;
6495 case SECCAT_TDATA:
6496 prefix = one_only ? ".td" : ".tdata";
6497 break;
6498 case SECCAT_TBSS:
6499 prefix = one_only ? ".tb" : ".tbss";
6500 break;
6501 default:
6502 gcc_unreachable ();
6505 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
6506 name = targetm.strip_name_encoding (name);
6508 /* If we're using one_only, then there needs to be a .gnu.linkonce
6509 prefix to the section name. */
6510 linkonce = one_only ? ".gnu.linkonce" : "";
6512 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6514 DECL_SECTION_NAME (decl) = build_string (strlen (string), string);
6517 /* Like compute_reloc_for_constant, except for an RTX. The return value
6518 is a mask for which bit 1 indicates a global relocation, and bit 0
6519 indicates a local relocation. */
6521 static int
6522 compute_reloc_for_rtx_1 (rtx *xp, void *data)
6524 int *preloc = (int *) data;
6525 rtx x = *xp;
6527 switch (GET_CODE (x))
6529 case SYMBOL_REF:
6530 *preloc |= SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6531 break;
6532 case LABEL_REF:
6533 *preloc |= 1;
6534 break;
6535 default:
6536 break;
6539 return 0;
6542 static int
6543 compute_reloc_for_rtx (rtx x)
6545 int reloc;
6547 switch (GET_CODE (x))
6549 case CONST:
6550 case SYMBOL_REF:
6551 case LABEL_REF:
6552 reloc = 0;
6553 for_each_rtx (&x, compute_reloc_for_rtx_1, &reloc);
6554 return reloc;
6556 default:
6557 return 0;
6561 section *
6562 default_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
6563 rtx x,
6564 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6566 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6567 return data_section;
6568 else
6569 return readonly_data_section;
6572 section *
6573 default_elf_select_rtx_section (enum machine_mode mode, rtx x,
6574 unsigned HOST_WIDE_INT align)
6576 int reloc = compute_reloc_for_rtx (x);
6578 /* ??? Handle small data here somehow. */
6580 if (reloc & targetm.asm_out.reloc_rw_mask ())
6582 if (reloc == 1)
6583 return get_named_section (NULL, ".data.rel.ro.local", 1);
6584 else
6585 return get_named_section (NULL, ".data.rel.ro", 3);
6588 return mergeable_constant_section (mode, align, 0);
6591 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6593 void
6594 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6596 rtx symbol;
6597 int flags;
6599 /* Careful not to prod global register variables. */
6600 if (!MEM_P (rtl))
6601 return;
6602 symbol = XEXP (rtl, 0);
6603 if (GET_CODE (symbol) != SYMBOL_REF)
6604 return;
6606 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6607 if (TREE_CODE (decl) == FUNCTION_DECL)
6608 flags |= SYMBOL_FLAG_FUNCTION;
6609 if (targetm.binds_local_p (decl))
6610 flags |= SYMBOL_FLAG_LOCAL;
6611 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6612 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6613 else if (targetm.in_small_data_p (decl))
6614 flags |= SYMBOL_FLAG_SMALL;
6615 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6616 being PUBLIC, the thing *must* be defined in this translation unit.
6617 Prevent this buglet from being propagated into rtl code as well. */
6618 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6619 flags |= SYMBOL_FLAG_EXTERNAL;
6621 SYMBOL_REF_FLAGS (symbol) = flags;
6624 /* By default, we do nothing for encode_section_info, so we need not
6625 do anything but discard the '*' marker. */
6627 const char *
6628 default_strip_name_encoding (const char *str)
6630 return str + (*str == '*');
6633 #ifdef ASM_OUTPUT_DEF
6634 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6635 anchor relative to ".", the current section position. */
6637 void
6638 default_asm_output_anchor (rtx symbol)
6640 char buffer[100];
6642 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6643 SYMBOL_REF_BLOCK_OFFSET (symbol));
6644 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6646 #endif
6648 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6650 bool
6651 default_use_anchors_for_symbol_p (const_rtx symbol)
6653 section *sect;
6654 tree decl;
6656 /* Don't use anchors for mergeable sections. The linker might move
6657 the objects around. */
6658 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6659 if (sect->common.flags & SECTION_MERGE)
6660 return false;
6662 /* Don't use anchors for small data sections. The small data register
6663 acts as an anchor for such sections. */
6664 if (sect->common.flags & SECTION_SMALL)
6665 return false;
6667 decl = SYMBOL_REF_DECL (symbol);
6668 if (decl && DECL_P (decl))
6670 /* Don't use section anchors for decls that might be defined or
6671 usurped by other modules. */
6672 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6673 return false;
6675 /* Don't use section anchors for decls that will be placed in a
6676 small data section. */
6677 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6678 one above. The problem is that we only use SECTION_SMALL for
6679 sections that should be marked as small in the section directive. */
6680 if (targetm.in_small_data_p (decl))
6681 return false;
6683 return true;
6686 /* Return true when RESOLUTION indicate that symbol will be bound to the
6687 definition provided by current .o file. */
6689 static bool
6690 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
6692 return (resolution == LDPR_PREVAILING_DEF
6693 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6694 || resolution == LDPR_PREVAILING_DEF_IRONLY);
6697 /* Return true when RESOLUTION indicate that symbol will be bound locally
6698 within current executable or DSO. */
6700 static bool
6701 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
6703 return (resolution == LDPR_PREVAILING_DEF
6704 || resolution == LDPR_PREVAILING_DEF_IRONLY
6705 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6706 || resolution == LDPR_PREEMPTED_REG
6707 || resolution == LDPR_PREEMPTED_IR
6708 || resolution == LDPR_RESOLVED_IR
6709 || resolution == LDPR_RESOLVED_EXEC);
6712 /* Assume ELF-ish defaults, since that's pretty much the most liberal
6713 wrt cross-module name binding. */
6715 bool
6716 default_binds_local_p (const_tree exp)
6718 return default_binds_local_p_1 (exp, flag_shlib);
6721 bool
6722 default_binds_local_p_1 (const_tree exp, int shlib)
6724 bool local_p;
6725 bool resolved_locally = false;
6726 bool resolved_to_local_def = false;
6728 /* With resolution file in hands, take look into resolutions.
6729 We can't just return true for resolved_locally symbols,
6730 because dynamic linking might overwrite symbols
6731 in shared libraries. */
6732 if (TREE_CODE (exp) == VAR_DECL && TREE_PUBLIC (exp)
6733 && (TREE_STATIC (exp) || DECL_EXTERNAL (exp)))
6735 varpool_node *vnode = varpool_get_node (exp);
6736 if (vnode && (resolution_local_p (vnode->resolution) || vnode->in_other_partition))
6737 resolved_locally = true;
6738 if (vnode
6739 && resolution_to_local_definition_p (vnode->resolution))
6740 resolved_to_local_def = true;
6742 else if (TREE_CODE (exp) == FUNCTION_DECL && TREE_PUBLIC (exp))
6744 struct cgraph_node *node = cgraph_get_node (exp);
6745 if (node
6746 && (resolution_local_p (node->resolution) || node->in_other_partition))
6747 resolved_locally = true;
6748 if (node
6749 && resolution_to_local_definition_p (node->resolution))
6750 resolved_to_local_def = true;
6753 /* A non-decl is an entry in the constant pool. */
6754 if (!DECL_P (exp))
6755 local_p = true;
6756 /* Weakrefs may not bind locally, even though the weakref itself is always
6757 static and therefore local. Similarly, the resolver for ifunc functions
6758 might resolve to a non-local function.
6759 FIXME: We can resolve the weakref case more curefuly by looking at the
6760 weakref alias. */
6761 else if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
6762 || (TREE_CODE (exp) == FUNCTION_DECL
6763 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
6764 local_p = false;
6765 /* Static variables are always local. */
6766 else if (! TREE_PUBLIC (exp))
6767 local_p = true;
6768 /* A variable is local if the user has said explicitly that it will
6769 be. */
6770 else if ((DECL_VISIBILITY_SPECIFIED (exp)
6771 || resolved_to_local_def)
6772 && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6773 local_p = true;
6774 /* Variables defined outside this object might not be local. */
6775 else if (DECL_EXTERNAL (exp) && !resolved_locally)
6776 local_p = false;
6777 /* If defined in this object and visibility is not default, must be
6778 local. */
6779 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6780 local_p = true;
6781 /* Default visibility weak data can be overridden by a strong symbol
6782 in another module and so are not local. */
6783 else if (DECL_WEAK (exp)
6784 && !resolved_locally)
6785 local_p = false;
6786 /* If PIC, then assume that any global name can be overridden by
6787 symbols resolved from other modules. */
6788 else if (shlib)
6789 local_p = false;
6790 /* Uninitialized COMMON variable may be unified with symbols
6791 resolved from other modules. */
6792 else if (DECL_COMMON (exp)
6793 && !resolved_locally
6794 && (DECL_INITIAL (exp) == NULL
6795 || DECL_INITIAL (exp) == error_mark_node))
6796 local_p = false;
6797 /* Otherwise we're left with initialized (or non-common) global data
6798 which is of necessity defined locally. */
6799 else
6800 local_p = true;
6802 return local_p;
6805 /* Return true when references to DECL must bind to current definition in
6806 final executable.
6808 The condition is usually equivalent to whether the function binds to the
6809 current module (shared library or executable), that is to binds_local_p.
6810 We use this fact to avoid need for another target hook and implement
6811 the logic using binds_local_p and just special cases where
6812 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
6813 the weak definitions (that can be overwritten at linktime by other
6814 definition from different object file) and when resolution info is available
6815 we simply use the knowledge passed to us by linker plugin. */
6816 bool
6817 decl_binds_to_current_def_p (tree decl)
6819 gcc_assert (DECL_P (decl));
6820 if (!targetm.binds_local_p (decl))
6821 return false;
6822 if (!TREE_PUBLIC (decl))
6823 return true;
6824 /* When resolution is available, just use it. */
6825 if (TREE_CODE (decl) == VAR_DECL
6826 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl)))
6828 varpool_node *vnode = varpool_get_node (decl);
6829 if (vnode
6830 && vnode->resolution != LDPR_UNKNOWN)
6831 return resolution_to_local_definition_p (vnode->resolution);
6833 else if (TREE_CODE (decl) == FUNCTION_DECL)
6835 struct cgraph_node *node = cgraph_get_node (decl);
6836 if (node
6837 && node->resolution != LDPR_UNKNOWN)
6838 return resolution_to_local_definition_p (node->resolution);
6840 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
6841 binds locally but still can be overwritten), DECL_COMMON (can be merged
6842 with a non-common definition somewhere in the same module) or
6843 DECL_EXTERNAL.
6844 This rely on fact that binds_local_p behave as decl_replaceable_p
6845 for all other declaration types. */
6846 if (DECL_WEAK (decl))
6847 return false;
6848 if (DECL_COMMON (decl)
6849 && (DECL_INITIAL (decl) == NULL
6850 || DECL_INITIAL (decl) == error_mark_node))
6851 return false;
6852 if (DECL_EXTERNAL (decl))
6853 return false;
6854 return true;
6857 /* A replaceable function or variable is one which may be replaced
6858 at link-time with an entirely different definition, provided that the
6859 replacement has the same type. For example, functions declared
6860 with __attribute__((weak)) on most systems are replaceable.
6862 COMDAT functions are not replaceable, since all definitions of the
6863 function must be equivalent. It is important that COMDAT functions
6864 not be treated as replaceable so that use of C++ template
6865 instantiations is not penalized. */
6867 bool
6868 decl_replaceable_p (tree decl)
6870 gcc_assert (DECL_P (decl));
6871 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
6872 return false;
6873 return !decl_binds_to_current_def_p (decl);
6876 /* Default function to output code that will globalize a label. A
6877 target must define GLOBAL_ASM_OP or provide its own function to
6878 globalize a label. */
6879 #ifdef GLOBAL_ASM_OP
6880 void
6881 default_globalize_label (FILE * stream, const char *name)
6883 fputs (GLOBAL_ASM_OP, stream);
6884 assemble_name (stream, name);
6885 putc ('\n', stream);
6887 #endif /* GLOBAL_ASM_OP */
6889 /* Default function to output code that will globalize a declaration. */
6890 void
6891 default_globalize_decl_name (FILE * stream, tree decl)
6893 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
6894 targetm.asm_out.globalize_label (stream, name);
6897 /* Default function to output a label for unwind information. The
6898 default is to do nothing. A target that needs nonlocal labels for
6899 unwind information must provide its own function to do this. */
6900 void
6901 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
6902 tree decl ATTRIBUTE_UNUSED,
6903 int for_eh ATTRIBUTE_UNUSED,
6904 int empty ATTRIBUTE_UNUSED)
6908 /* Default function to output a label to divide up the exception table.
6909 The default is to do nothing. A target that needs/wants to divide
6910 up the table must provide it's own function to do this. */
6911 void
6912 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
6916 /* This is how to output an internal numbered label where PREFIX is
6917 the class of label and LABELNO is the number within the class. */
6919 void
6920 default_generate_internal_label (char *buf, const char *prefix,
6921 unsigned long labelno)
6923 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6926 /* This is how to output an internal numbered label where PREFIX is
6927 the class of label and LABELNO is the number within the class. */
6929 void
6930 default_internal_label (FILE *stream, const char *prefix,
6931 unsigned long labelno)
6933 char *const buf = (char *) alloca (40 + strlen (prefix));
6934 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6935 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
6939 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
6941 void
6942 default_asm_declare_constant_name (FILE *file, const char *name,
6943 const_tree exp ATTRIBUTE_UNUSED,
6944 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
6946 assemble_label (file, name);
6949 /* This is the default behavior at the beginning of a file. It's
6950 controlled by two other target-hook toggles. */
6951 void
6952 default_file_start (void)
6954 if (targetm.asm_file_start_app_off
6955 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
6956 fputs (ASM_APP_OFF, asm_out_file);
6958 if (targetm.asm_file_start_file_directive)
6959 output_file_directive (asm_out_file, main_input_filename);
6962 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
6963 which emits a special section directive used to indicate whether or
6964 not this object file needs an executable stack. This is primarily
6965 a GNU extension to ELF but could be used on other targets. */
6967 int trampolines_created;
6969 void
6970 file_end_indicate_exec_stack (void)
6972 unsigned int flags = SECTION_DEBUG;
6973 if (trampolines_created)
6974 flags |= SECTION_CODE;
6976 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
6979 /* Emit a special section directive to indicate that this object file
6980 was compiled with -fsplit-stack. This is used to let the linker
6981 detect calls between split-stack code and non-split-stack code, so
6982 that it can modify the split-stack code to allocate a sufficiently
6983 large stack. We emit another special section if there are any
6984 functions in this file which have the no_split_stack attribute, to
6985 prevent the linker from warning about being unable to convert the
6986 functions if they call non-split-stack code. */
6988 void
6989 file_end_indicate_split_stack (void)
6991 if (flag_split_stack)
6993 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
6994 NULL));
6995 if (saw_no_split_stack)
6996 switch_to_section (get_section (".note.GNU-no-split-stack",
6997 SECTION_DEBUG, NULL));
7001 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
7002 a get_unnamed_section callback. */
7004 void
7005 output_section_asm_op (const void *directive)
7007 fprintf (asm_out_file, "%s\n", (const char *) directive);
7010 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
7011 the current section is NEW_SECTION. */
7013 void
7014 switch_to_section (section *new_section)
7016 if (in_section == new_section)
7017 return;
7019 if (new_section->common.flags & SECTION_FORGET)
7020 in_section = NULL;
7021 else
7022 in_section = new_section;
7024 switch (SECTION_STYLE (new_section))
7026 case SECTION_NAMED:
7027 targetm.asm_out.named_section (new_section->named.name,
7028 new_section->named.common.flags,
7029 new_section->named.decl);
7030 break;
7032 case SECTION_UNNAMED:
7033 new_section->unnamed.callback (new_section->unnamed.data);
7034 break;
7036 case SECTION_NOSWITCH:
7037 gcc_unreachable ();
7038 break;
7041 new_section->common.flags |= SECTION_DECLARED;
7044 /* If block symbol SYMBOL has not yet been assigned an offset, place
7045 it at the end of its block. */
7047 void
7048 place_block_symbol (rtx symbol)
7050 unsigned HOST_WIDE_INT size, mask, offset;
7051 struct constant_descriptor_rtx *desc;
7052 unsigned int alignment;
7053 struct object_block *block;
7054 tree decl;
7056 gcc_assert (SYMBOL_REF_BLOCK (symbol));
7057 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7058 return;
7060 /* Work out the symbol's size and alignment. */
7061 if (CONSTANT_POOL_ADDRESS_P (symbol))
7063 desc = SYMBOL_REF_CONSTANT (symbol);
7064 alignment = desc->align;
7065 size = GET_MODE_SIZE (desc->mode);
7067 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7069 decl = SYMBOL_REF_DECL (symbol);
7070 alignment = DECL_ALIGN (decl);
7071 size = get_constant_size (DECL_INITIAL (decl));
7072 if ((flag_sanitize & SANITIZE_ADDRESS)
7073 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7074 && asan_protect_global (DECL_INITIAL (decl)))
7075 size += asan_red_zone_size (size);
7077 else
7079 decl = SYMBOL_REF_DECL (symbol);
7080 alignment = get_variable_align (decl);
7081 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7082 if ((flag_sanitize & SANITIZE_ADDRESS)
7083 && asan_protect_global (decl))
7085 size += asan_red_zone_size (size);
7086 alignment = MAX (alignment,
7087 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7091 /* Calculate the object's offset from the start of the block. */
7092 block = SYMBOL_REF_BLOCK (symbol);
7093 mask = alignment / BITS_PER_UNIT - 1;
7094 offset = (block->size + mask) & ~mask;
7095 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7097 /* Record the block's new alignment and size. */
7098 block->alignment = MAX (block->alignment, alignment);
7099 block->size = offset + size;
7101 vec_safe_push (block->objects, symbol);
7104 /* Return the anchor that should be used to address byte offset OFFSET
7105 from the first object in BLOCK. MODEL is the TLS model used
7106 to access it. */
7109 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7110 enum tls_model model)
7112 char label[100];
7113 unsigned int begin, middle, end;
7114 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7115 rtx anchor;
7117 /* Work out the anchor's offset. Use an offset of 0 for the first
7118 anchor so that we don't pessimize the case where we take the address
7119 of a variable at the beginning of the block. This is particularly
7120 useful when a block has only one variable assigned to it.
7122 We try to place anchors RANGE bytes apart, so there can then be
7123 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7124 a ptr_mode offset. With some target settings, the lowest such
7125 anchor might be out of range for the lowest ptr_mode offset;
7126 likewise the highest anchor for the highest offset. Use anchors
7127 at the extreme ends of the ptr_mode range in such cases.
7129 All arithmetic uses unsigned integers in order to avoid
7130 signed overflow. */
7131 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7132 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7133 range = max_offset - min_offset + 1;
7134 if (range == 0)
7135 offset = 0;
7136 else
7138 bias = 1 << (GET_MODE_BITSIZE (ptr_mode) - 1);
7139 if (offset < 0)
7141 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7142 delta -= delta % range;
7143 if (delta > bias)
7144 delta = bias;
7145 offset = (HOST_WIDE_INT) (-delta);
7147 else
7149 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7150 delta -= delta % range;
7151 if (delta > bias - 1)
7152 delta = bias - 1;
7153 offset = (HOST_WIDE_INT) delta;
7157 /* Do a binary search to see if there's already an anchor we can use.
7158 Set BEGIN to the new anchor's index if not. */
7159 begin = 0;
7160 end = vec_safe_length (block->anchors);
7161 while (begin != end)
7163 middle = (end + begin) / 2;
7164 anchor = (*block->anchors)[middle];
7165 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7166 end = middle;
7167 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7168 begin = middle + 1;
7169 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7170 end = middle;
7171 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7172 begin = middle + 1;
7173 else
7174 return anchor;
7177 /* Create a new anchor with a unique label. */
7178 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7179 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7180 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7181 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7183 /* Insert it at index BEGIN. */
7184 vec_safe_insert (block->anchors, begin, anchor);
7185 return anchor;
7188 /* Output the objects in BLOCK. */
7190 static void
7191 output_object_block (struct object_block *block)
7193 struct constant_descriptor_rtx *desc;
7194 unsigned int i;
7195 HOST_WIDE_INT offset;
7196 tree decl;
7197 rtx symbol;
7199 if (!block->objects)
7200 return;
7202 /* Switch to the section and make sure that the first byte is
7203 suitably aligned. */
7204 switch_to_section (block->sect);
7205 assemble_align (block->alignment);
7207 /* Define the values of all anchors relative to the current section
7208 position. */
7209 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7210 targetm.asm_out.output_anchor (symbol);
7212 /* Output the objects themselves. */
7213 offset = 0;
7214 FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7216 /* Move to the object's offset, padding with zeros if necessary. */
7217 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7218 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7219 if (CONSTANT_POOL_ADDRESS_P (symbol))
7221 desc = SYMBOL_REF_CONSTANT (symbol);
7222 output_constant_pool_1 (desc, 1);
7223 offset += GET_MODE_SIZE (desc->mode);
7225 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7227 HOST_WIDE_INT size;
7228 decl = SYMBOL_REF_DECL (symbol);
7229 assemble_constant_contents (DECL_INITIAL (decl), XSTR (symbol, 0),
7230 DECL_ALIGN (decl));
7231 size = get_constant_size (DECL_INITIAL (decl));
7232 offset += size;
7233 if ((flag_sanitize & SANITIZE_ADDRESS)
7234 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7235 && asan_protect_global (DECL_INITIAL (decl)))
7237 size = asan_red_zone_size (size);
7238 assemble_zeros (size);
7239 offset += size;
7242 else
7244 HOST_WIDE_INT size;
7245 decl = SYMBOL_REF_DECL (symbol);
7246 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7247 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7248 offset += size;
7249 if ((flag_sanitize & SANITIZE_ADDRESS)
7250 && asan_protect_global (decl))
7252 size = asan_red_zone_size (size);
7253 assemble_zeros (size);
7254 offset += size;
7260 /* A htab_traverse callback used to call output_object_block for
7261 each member of object_block_htab. */
7263 static int
7264 output_object_block_htab (void **slot, void *data ATTRIBUTE_UNUSED)
7266 output_object_block ((struct object_block *) (*slot));
7267 return 1;
7270 /* Output the definitions of all object_blocks. */
7272 void
7273 output_object_blocks (void)
7275 htab_traverse (object_block_htab, output_object_block_htab, NULL);
7278 /* This function provides a possible implementation of the
7279 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7280 by -frecord-gcc-switches it creates a new mergeable, string section in the
7281 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7282 contains the switches in ASCII format.
7284 FIXME: This code does not correctly handle double quote characters
7285 that appear inside strings, (it strips them rather than preserving them).
7286 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7287 characters - instead it treats them as sub-string separators. Since
7288 we want to emit NUL strings terminators into the object file we have to use
7289 ASM_OUTPUT_SKIP. */
7292 elf_record_gcc_switches (print_switch_type type, const char * name)
7294 switch (type)
7296 case SWITCH_TYPE_PASSED:
7297 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7298 ASM_OUTPUT_SKIP (asm_out_file, (unsigned HOST_WIDE_INT) 1);
7299 break;
7301 case SWITCH_TYPE_DESCRIPTIVE:
7302 if (name == NULL)
7304 /* Distinguish between invocations where name is NULL. */
7305 static bool started = false;
7307 if (!started)
7309 section * sec;
7311 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7312 SECTION_DEBUG
7313 | SECTION_MERGE
7314 | SECTION_STRINGS
7315 | (SECTION_ENTSIZE & 1),
7316 NULL);
7317 switch_to_section (sec);
7318 started = true;
7322 default:
7323 break;
7326 /* The return value is currently ignored by the caller, but must be 0.
7327 For -fverbose-asm the return value would be the number of characters
7328 emitted into the assembler file. */
7329 return 0;
7332 /* Emit text to declare externally defined symbols. It is needed to
7333 properly support non-default visibility. */
7334 void
7335 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7336 tree decl,
7337 const char *name ATTRIBUTE_UNUSED)
7339 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7340 set in order to avoid putting out names that are never really
7341 used. */
7342 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7343 && targetm.binds_local_p (decl))
7344 maybe_assemble_visibility (decl);
7347 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7349 void
7350 default_asm_output_source_filename (FILE *file, const char *name)
7352 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7353 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7354 #else
7355 fprintf (file, "\t.file\t");
7356 output_quoted_string (file, name);
7357 putc ('\n', file);
7358 #endif
7361 /* Output a file name in the form wanted by System V. */
7363 void
7364 output_file_directive (FILE *asm_file, const char *input_name)
7366 int len;
7367 const char *na;
7369 if (input_name == NULL)
7370 input_name = "<stdin>";
7371 else
7372 input_name = remap_debug_filename (input_name);
7374 len = strlen (input_name);
7375 na = input_name + len;
7377 /* NA gets INPUT_NAME sans directory names. */
7378 while (na > input_name)
7380 if (IS_DIR_SEPARATOR (na[-1]))
7381 break;
7382 na--;
7385 targetm.asm_out.output_source_filename (asm_file, na);
7388 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7389 EXP. */
7391 make_debug_expr_from_rtl (const_rtx exp)
7393 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7394 enum machine_mode mode = GET_MODE (exp);
7395 rtx dval;
7397 DECL_ARTIFICIAL (ddecl) = 1;
7398 if (REG_P (exp) && REG_EXPR (exp))
7399 type = TREE_TYPE (REG_EXPR (exp));
7400 else if (MEM_P (exp) && MEM_EXPR (exp))
7401 type = TREE_TYPE (MEM_EXPR (exp));
7402 else
7403 type = NULL_TREE;
7404 if (type && TYPE_MODE (type) == mode)
7405 TREE_TYPE (ddecl) = type;
7406 else
7407 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7408 DECL_MODE (ddecl) = mode;
7409 dval = gen_rtx_DEBUG_EXPR (mode);
7410 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7411 SET_DECL_RTL (ddecl, dval);
7412 return dval;
7415 #ifdef ELF_ASCII_ESCAPES
7416 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7418 void
7419 default_elf_asm_output_limited_string (FILE *f, const char *s)
7421 int escape;
7422 unsigned char c;
7424 fputs (STRING_ASM_OP, f);
7425 putc ('"', f);
7426 while (*s != '\0')
7428 c = *s;
7429 escape = ELF_ASCII_ESCAPES[c];
7430 switch (escape)
7432 case 0:
7433 putc (c, f);
7434 break;
7435 case 1:
7436 /* TODO: Print in hex with fast function, important for -flto. */
7437 fprintf (f, "\\%03o", c);
7438 break;
7439 default:
7440 putc ('\\', f);
7441 putc (escape, f);
7442 break;
7444 s++;
7446 putc ('\"', f);
7447 putc ('\n', f);
7450 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7452 void
7453 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7455 const char *limit = s + len;
7456 const char *last_null = NULL;
7457 unsigned bytes_in_chunk = 0;
7458 unsigned char c;
7459 int escape;
7461 for (; s < limit; s++)
7463 const char *p;
7465 if (bytes_in_chunk >= 60)
7467 putc ('\"', f);
7468 putc ('\n', f);
7469 bytes_in_chunk = 0;
7472 if (s > last_null)
7474 for (p = s; p < limit && *p != '\0'; p++)
7475 continue;
7476 last_null = p;
7478 else
7479 p = last_null;
7481 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7483 if (bytes_in_chunk > 0)
7485 putc ('\"', f);
7486 putc ('\n', f);
7487 bytes_in_chunk = 0;
7490 default_elf_asm_output_limited_string (f, s);
7491 s = p;
7493 else
7495 if (bytes_in_chunk == 0)
7496 fputs (ASCII_DATA_ASM_OP "\"", f);
7498 c = *s;
7499 escape = ELF_ASCII_ESCAPES[c];
7500 switch (escape)
7502 case 0:
7503 putc (c, f);
7504 bytes_in_chunk++;
7505 break;
7506 case 1:
7507 /* TODO: Print in hex with fast function, important for -flto. */
7508 fprintf (f, "\\%03o", c);
7509 bytes_in_chunk += 4;
7510 break;
7511 default:
7512 putc ('\\', f);
7513 putc (escape, f);
7514 bytes_in_chunk += 2;
7515 break;
7521 if (bytes_in_chunk > 0)
7523 putc ('\"', f);
7524 putc ('\n', f);
7527 #endif
7529 static GTY(()) section *elf_init_array_section;
7530 static GTY(()) section *elf_fini_array_section;
7532 static section *
7533 get_elf_initfini_array_priority_section (int priority,
7534 bool constructor_p)
7536 section *sec;
7537 if (priority != DEFAULT_INIT_PRIORITY)
7539 char buf[18];
7540 sprintf (buf, "%s.%.5u",
7541 constructor_p ? ".init_array" : ".fini_array",
7542 priority);
7543 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7545 else
7547 if (constructor_p)
7549 if (elf_init_array_section == NULL)
7550 elf_init_array_section
7551 = get_section (".init_array",
7552 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7553 sec = elf_init_array_section;
7555 else
7557 if (elf_fini_array_section == NULL)
7558 elf_fini_array_section
7559 = get_section (".fini_array",
7560 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7561 sec = elf_fini_array_section;
7564 return sec;
7567 /* Use .init_array section for constructors. */
7569 void
7570 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7572 section *sec = get_elf_initfini_array_priority_section (priority,
7573 true);
7574 assemble_addr_to_section (symbol, sec);
7577 /* Use .fini_array section for destructors. */
7579 void
7580 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7582 section *sec = get_elf_initfini_array_priority_section (priority,
7583 false);
7584 assemble_addr_to_section (symbol, sec);
7587 /* Default TARGET_ASM_OUTPUT_IDENT hook.
7589 This is a bit of a cheat. The real default is a no-op, but this
7590 hook is the default for all targets with a .ident directive. */
7592 void
7593 default_asm_output_ident_directive (const char *ident_str)
7595 const char *ident_asm_op = "\t.ident\t";
7597 /* If we are still in the front end, do not write out the string
7598 to asm_out_file. Instead, add a fake top-level asm statement.
7599 This allows the front ends to use this hook without actually
7600 writing to asm_out_file, to handle #ident or Pragma Ident. */
7601 if (cgraph_state == CGRAPH_STATE_PARSING)
7603 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
7604 add_asm_node (build_string (strlen (buf), buf));
7606 else
7607 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
7610 #include "gt-varasm.h"