* pt.c (lookup_template_class_1): Splice out abi_tag attribute if
[official-gcc.git] / gcc / varasm.c
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1 /* Output variables, constants and external declarations, for GNU compiler.
2 Copyright (C) 1987-2014 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
21 /* This file handles generation of all the assembler code
22 *except* the instructions of a function.
23 This includes declarations of variables and their initial values.
25 We also output the assembler code for constants stored in memory
26 and are responsible for combining constants with the same value. */
28 #include "config.h"
29 #include "system.h"
30 #include "coretypes.h"
31 #include "tm.h"
32 #include "rtl.h"
33 #include "tree.h"
34 #include "stor-layout.h"
35 #include "stringpool.h"
36 #include "varasm.h"
37 #include "flags.h"
38 #include "function.h"
39 #include "expr.h"
40 #include "hard-reg-set.h"
41 #include "regs.h"
42 #include "output.h"
43 #include "diagnostic-core.h"
44 #include "hashtab.h"
45 #include "ggc.h"
46 #include "langhooks.h"
47 #include "tm_p.h"
48 #include "debug.h"
49 #include "target.h"
50 #include "common/common-target.h"
51 #include "targhooks.h"
52 #include "cgraph.h"
53 #include "hash-set.h"
54 #include "asan.h"
55 #include "basic-block.h"
56 #include "rtl-iter.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 void output_constant_def_contents (rtx);
118 static void output_addressed_constants (tree);
119 static unsigned HOST_WIDE_INT output_constant (tree, unsigned HOST_WIDE_INT,
120 unsigned int);
121 static void globalize_decl (tree);
122 static bool decl_readonly_section_1 (enum section_category);
123 #ifdef BSS_SECTION_ASM_OP
124 #ifdef ASM_OUTPUT_ALIGNED_BSS
125 static void asm_output_aligned_bss (FILE *, tree, const char *,
126 unsigned HOST_WIDE_INT, int)
127 ATTRIBUTE_UNUSED;
128 #endif
129 #endif /* BSS_SECTION_ASM_OP */
130 static void mark_weak (tree);
131 static void output_constant_pool (const char *, tree);
133 /* Well-known sections, each one associated with some sort of *_ASM_OP. */
134 section *text_section;
135 section *data_section;
136 section *readonly_data_section;
137 section *sdata_section;
138 section *ctors_section;
139 section *dtors_section;
140 section *bss_section;
141 section *sbss_section;
143 /* Various forms of common section. All are guaranteed to be nonnull. */
144 section *tls_comm_section;
145 section *comm_section;
146 section *lcomm_section;
148 /* A SECTION_NOSWITCH section used for declaring global BSS variables.
149 May be null. */
150 section *bss_noswitch_section;
152 /* The section that holds the main exception table, when known. The section
153 is set either by the target's init_sections hook or by the first call to
154 switch_to_exception_section. */
155 section *exception_section;
157 /* The section that holds the DWARF2 frame unwind information, when known.
158 The section is set either by the target's init_sections hook or by the
159 first call to switch_to_eh_frame_section. */
160 section *eh_frame_section;
162 /* asm_out_file's current section. This is NULL if no section has yet
163 been selected or if we lose track of what the current section is. */
164 section *in_section;
166 /* True if code for the current function is currently being directed
167 at the cold section. */
168 bool in_cold_section_p;
170 /* A linked list of all the unnamed sections. */
171 static GTY(()) section *unnamed_sections;
173 /* Return a nonzero value if DECL has a section attribute. */
174 #define IN_NAMED_SECTION(DECL) \
175 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \
176 && DECL_SECTION_NAME (DECL) != NULL)
178 /* Hash table of named sections. */
179 static GTY((param_is (section))) htab_t section_htab;
181 /* A table of object_blocks, indexed by section. */
182 static GTY((param_is (struct object_block))) htab_t object_block_htab;
184 /* The next number to use for internal anchor labels. */
185 static GTY(()) int anchor_labelno;
187 /* A pool of constants that can be shared between functions. */
188 static GTY(()) struct rtx_constant_pool *shared_constant_pool;
190 /* Helper routines for maintaining section_htab. */
192 static int
193 section_entry_eq (const void *p1, const void *p2)
195 const section *old = (const section *) p1;
196 const char *new_name = (const char *) p2;
198 return strcmp (old->named.name, new_name) == 0;
201 static hashval_t
202 section_entry_hash (const void *p)
204 const section *old = (const section *) p;
205 return htab_hash_string (old->named.name);
208 /* Return a hash value for section SECT. */
210 static hashval_t
211 hash_section (section *sect)
213 if (sect->common.flags & SECTION_NAMED)
214 return htab_hash_string (sect->named.name);
215 return sect->common.flags;
218 /* Helper routines for maintaining object_block_htab. */
220 static int
221 object_block_entry_eq (const void *p1, const void *p2)
223 const struct object_block *old = (const struct object_block *) p1;
224 const section *new_section = (const section *) p2;
226 return old->sect == new_section;
229 static hashval_t
230 object_block_entry_hash (const void *p)
232 const struct object_block *old = (const struct object_block *) p;
233 return hash_section (old->sect);
236 /* Return a new unnamed section with the given fields. */
238 section *
239 get_unnamed_section (unsigned int flags, void (*callback) (const void *),
240 const void *data)
242 section *sect;
244 sect = ggc_alloc<section> ();
245 sect->unnamed.common.flags = flags | SECTION_UNNAMED;
246 sect->unnamed.callback = callback;
247 sect->unnamed.data = data;
248 sect->unnamed.next = unnamed_sections;
250 unnamed_sections = sect;
251 return sect;
254 /* Return a SECTION_NOSWITCH section with the given fields. */
256 static section *
257 get_noswitch_section (unsigned int flags, noswitch_section_callback callback)
259 section *sect;
261 sect = ggc_alloc<section> ();
262 sect->noswitch.common.flags = flags | SECTION_NOSWITCH;
263 sect->noswitch.callback = callback;
265 return sect;
268 /* Return the named section structure associated with NAME. Create
269 a new section with the given fields if no such structure exists. */
271 section *
272 get_section (const char *name, unsigned int flags, tree decl)
274 section *sect, **slot;
276 slot = (section **)
277 htab_find_slot_with_hash (section_htab, name,
278 htab_hash_string (name), INSERT);
279 flags |= SECTION_NAMED;
280 if (*slot == NULL)
282 sect = ggc_alloc<section> ();
283 sect->named.common.flags = flags;
284 sect->named.name = ggc_strdup (name);
285 sect->named.decl = decl;
286 *slot = sect;
288 else
290 sect = *slot;
291 if ((sect->common.flags & ~SECTION_DECLARED) != flags
292 && ((sect->common.flags | flags) & SECTION_OVERRIDE) == 0)
294 /* It is fine if one of the section flags is
295 SECTION_WRITE | SECTION_RELRO and the other has none of these
296 flags (i.e. read-only) in named sections and either the
297 section hasn't been declared yet or has been declared as writable.
298 In that case just make sure the resulting flags are
299 SECTION_WRITE | SECTION_RELRO, ie. writable only because of
300 relocations. */
301 if (((sect->common.flags ^ flags) & (SECTION_WRITE | SECTION_RELRO))
302 == (SECTION_WRITE | SECTION_RELRO)
303 && (sect->common.flags
304 & ~(SECTION_DECLARED | SECTION_WRITE | SECTION_RELRO))
305 == (flags & ~(SECTION_WRITE | SECTION_RELRO))
306 && ((sect->common.flags & SECTION_DECLARED) == 0
307 || (sect->common.flags & SECTION_WRITE)))
309 sect->common.flags |= (SECTION_WRITE | SECTION_RELRO);
310 return sect;
312 /* Sanity check user variables for flag changes. */
313 if (sect->named.decl != NULL
314 && DECL_P (sect->named.decl)
315 && decl != sect->named.decl)
317 if (decl != NULL && DECL_P (decl))
318 error ("%+D causes a section type conflict with %D",
319 decl, sect->named.decl);
320 else
321 error ("section type conflict with %D", sect->named.decl);
322 inform (DECL_SOURCE_LOCATION (sect->named.decl),
323 "%qD was declared here", sect->named.decl);
325 else if (decl != NULL && DECL_P (decl))
326 error ("%+D causes a section type conflict", decl);
327 else
328 error ("section type conflict");
329 /* Make sure we don't error about one section multiple times. */
330 sect->common.flags |= SECTION_OVERRIDE;
333 return sect;
336 /* Return true if the current compilation mode benefits from having
337 objects grouped into blocks. */
339 static bool
340 use_object_blocks_p (void)
342 return flag_section_anchors;
345 /* Return the object_block structure for section SECT. Create a new
346 structure if we haven't created one already. Return null if SECT
347 itself is null. */
349 static struct object_block *
350 get_block_for_section (section *sect)
352 struct object_block *block;
353 void **slot;
355 if (sect == NULL)
356 return NULL;
358 slot = htab_find_slot_with_hash (object_block_htab, sect,
359 hash_section (sect), INSERT);
360 block = (struct object_block *) *slot;
361 if (block == NULL)
363 block = ggc_cleared_alloc<object_block> ();
364 block->sect = sect;
365 *slot = block;
367 return block;
370 /* Create a symbol with label LABEL and place it at byte offset
371 OFFSET in BLOCK. OFFSET can be negative if the symbol's offset
372 is not yet known. LABEL must be a garbage-collected string. */
374 static rtx
375 create_block_symbol (const char *label, struct object_block *block,
376 HOST_WIDE_INT offset)
378 rtx symbol;
379 unsigned int size;
381 /* Create the extended SYMBOL_REF. */
382 size = RTX_HDR_SIZE + sizeof (struct block_symbol);
383 symbol = (rtx) ggc_internal_alloc (size);
385 /* Initialize the normal SYMBOL_REF fields. */
386 memset (symbol, 0, size);
387 PUT_CODE (symbol, SYMBOL_REF);
388 PUT_MODE (symbol, Pmode);
389 XSTR (symbol, 0) = label;
390 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_HAS_BLOCK_INFO;
392 /* Initialize the block_symbol stuff. */
393 SYMBOL_REF_BLOCK (symbol) = block;
394 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
396 return symbol;
399 /* Return a section with a particular name and with whatever SECTION_*
400 flags section_type_flags deems appropriate. The name of the section
401 is taken from NAME if nonnull, otherwise it is taken from DECL's
402 DECL_SECTION_NAME. DECL is the decl associated with the section
403 (see the section comment for details) and RELOC is as for
404 section_type_flags. */
406 section *
407 get_named_section (tree decl, const char *name, int reloc)
409 unsigned int flags;
411 if (name == NULL)
413 gcc_assert (decl && DECL_P (decl) && DECL_SECTION_NAME (decl));
414 name = DECL_SECTION_NAME (decl);
417 flags = targetm.section_type_flags (decl, name, reloc);
418 return get_section (name, flags, decl);
421 /* Worker for resolve_unique_section. */
423 static bool
424 set_implicit_section (struct symtab_node *n, void *data ATTRIBUTE_UNUSED)
426 n->implicit_section = true;
427 return false;
430 /* If required, set DECL_SECTION_NAME to a unique name. */
432 void
433 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
434 int flag_function_or_data_sections)
436 if (DECL_SECTION_NAME (decl) == NULL
437 && targetm_common.have_named_sections
438 && (flag_function_or_data_sections
439 || DECL_COMDAT_GROUP (decl)))
441 targetm.asm_out.unique_section (decl, reloc);
442 if (DECL_SECTION_NAME (decl))
443 symtab_node::get (decl)->call_for_symbol_and_aliases
444 (set_implicit_section, NULL, true);
448 #ifdef BSS_SECTION_ASM_OP
450 #ifdef ASM_OUTPUT_ALIGNED_BSS
452 /* Utility function for targets to use in implementing
453 ASM_OUTPUT_ALIGNED_BSS.
454 ??? It is believed that this function will work in most cases so such
455 support is localized here. */
457 static void
458 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
459 const char *name, unsigned HOST_WIDE_INT size,
460 int align)
462 switch_to_section (bss_section);
463 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
464 #ifdef ASM_DECLARE_OBJECT_NAME
465 last_assemble_variable_decl = decl;
466 ASM_DECLARE_OBJECT_NAME (file, name, decl);
467 #else
468 /* Standard thing is just output label for the object. */
469 ASM_OUTPUT_LABEL (file, name);
470 #endif /* ASM_DECLARE_OBJECT_NAME */
471 ASM_OUTPUT_SKIP (file, size ? size : 1);
474 #endif
476 #endif /* BSS_SECTION_ASM_OP */
478 #ifndef USE_SELECT_SECTION_FOR_FUNCTIONS
479 /* Return the hot section for function DECL. Return text_section for
480 null DECLs. */
482 static section *
483 hot_function_section (tree decl)
485 if (decl != NULL_TREE
486 && DECL_SECTION_NAME (decl) != NULL
487 && targetm_common.have_named_sections)
488 return get_named_section (decl, NULL, 0);
489 else
490 return text_section;
492 #endif
494 /* Return section for TEXT_SECTION_NAME if DECL or DECL_SECTION_NAME (DECL)
495 is NULL.
497 When DECL_SECTION_NAME is non-NULL and it is implicit section and
498 NAMED_SECTION_SUFFIX is non-NULL, then produce section called
499 concatenate the name with NAMED_SECTION_SUFFIX.
500 Otherwise produce "TEXT_SECTION_NAME.IMPLICIT_NAME". */
502 section *
503 get_named_text_section (tree decl,
504 const char *text_section_name,
505 const char *named_section_suffix)
507 if (decl && DECL_SECTION_NAME (decl))
509 if (named_section_suffix)
511 const char *dsn = DECL_SECTION_NAME (decl);
512 const char *stripped_name;
513 char *name, *buffer;
515 name = (char *) alloca (strlen (dsn) + 1);
516 memcpy (name, dsn,
517 strlen (dsn) + 1);
519 stripped_name = targetm.strip_name_encoding (name);
521 buffer = ACONCAT ((stripped_name, named_section_suffix, NULL));
522 return get_named_section (decl, buffer, 0);
524 else if (symtab_node::get (decl)->implicit_section)
526 const char *name;
528 /* Do not try to split gnu_linkonce functions. This gets somewhat
529 slipperly. */
530 if (DECL_COMDAT_GROUP (decl) && !HAVE_COMDAT_GROUP)
531 return NULL;
532 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
533 name = targetm.strip_name_encoding (name);
534 return get_named_section (decl, ACONCAT ((text_section_name, ".",
535 name, NULL)), 0);
537 else
538 return NULL;
540 return get_named_section (decl, text_section_name, 0);
543 /* Choose named function section based on its frequency. */
545 section *
546 default_function_section (tree decl, enum node_frequency freq,
547 bool startup, bool exit)
549 #if defined HAVE_LD_EH_GC_SECTIONS && defined HAVE_LD_EH_GC_SECTIONS_BUG
550 /* Old GNU linkers have buggy --gc-section support, which sometimes
551 results in .gcc_except_table* sections being garbage collected. */
552 if (decl
553 && symtab_node::get (decl)->implicit_section)
554 return NULL;
555 #endif
557 if (!flag_reorder_functions
558 || !targetm_common.have_named_sections)
559 return NULL;
560 /* Startup code should go to startup subsection unless it is
561 unlikely executed (this happens especially with function splitting
562 where we can split away unnecessary parts of static constructors. */
563 if (startup && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
565 /* If we do have a profile or(and) LTO phase is executed, we do not need
566 these ELF section. */
567 if (!in_lto_p || !flag_profile_values)
568 return get_named_text_section (decl, ".text.startup", NULL);
569 else
570 return NULL;
573 /* Similarly for exit. */
574 if (exit && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
575 return get_named_text_section (decl, ".text.exit", NULL);
577 /* Group cold functions together, similarly for hot code. */
578 switch (freq)
580 case NODE_FREQUENCY_UNLIKELY_EXECUTED:
581 return get_named_text_section (decl, ".text.unlikely", NULL);
582 case NODE_FREQUENCY_HOT:
583 /* If we do have a profile or(and) LTO phase is executed, we do not need
584 these ELF section. */
585 if (!in_lto_p || !flag_profile_values)
586 return get_named_text_section (decl, ".text.hot", NULL);
587 default:
588 return NULL;
592 /* Return the section for function DECL.
594 If DECL is NULL_TREE, return the text section. We can be passed
595 NULL_TREE under some circumstances by dbxout.c at least.
597 If FORCE_COLD is true, return cold function section ignoring
598 the frequency info of cgraph_node. */
600 static section *
601 function_section_1 (tree decl, bool force_cold)
603 section *section = NULL;
604 enum node_frequency freq = NODE_FREQUENCY_NORMAL;
605 bool startup = false, exit = false;
607 if (decl)
609 struct cgraph_node *node = cgraph_node::get (decl);
611 if (node)
613 freq = node->frequency;
614 startup = node->only_called_at_startup;
615 exit = node->only_called_at_exit;
618 if (force_cold)
619 freq = NODE_FREQUENCY_UNLIKELY_EXECUTED;
621 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
622 if (decl != NULL_TREE
623 && DECL_SECTION_NAME (decl) != NULL)
625 if (targetm.asm_out.function_section)
626 section = targetm.asm_out.function_section (decl, freq,
627 startup, exit);
628 if (section)
629 return section;
630 return get_named_section (decl, NULL, 0);
632 else
633 return targetm.asm_out.select_section
634 (decl, freq == NODE_FREQUENCY_UNLIKELY_EXECUTED,
635 DECL_ALIGN (decl));
636 #else
637 if (targetm.asm_out.function_section)
638 section = targetm.asm_out.function_section (decl, freq, startup, exit);
639 if (section)
640 return section;
641 return hot_function_section (decl);
642 #endif
645 /* Return the section for function DECL.
647 If DECL is NULL_TREE, return the text section. We can be passed
648 NULL_TREE under some circumstances by dbxout.c at least. */
650 section *
651 function_section (tree decl)
653 /* Handle cases where function splitting code decides
654 to put function entry point into unlikely executed section
655 despite the fact that the function itself is not cold
656 (i.e. it is called rarely but contains a hot loop that is
657 better to live in hot subsection for the code locality). */
658 return function_section_1 (decl,
659 first_function_block_is_cold);
662 /* Return the section for the current function, take IN_COLD_SECTION_P
663 into account. */
665 section *
666 current_function_section (void)
668 return function_section_1 (current_function_decl, in_cold_section_p);
671 /* Tell assembler to switch to unlikely-to-be-executed text section. */
673 section *
674 unlikely_text_section (void)
676 return function_section_1 (current_function_decl, true);
679 /* When called within a function context, return true if the function
680 has been assigned a cold text section and if SECT is that section.
681 When called outside a function context, return true if SECT is the
682 default cold section. */
684 bool
685 unlikely_text_section_p (section *sect)
687 return sect == function_section_1 (current_function_decl, true);
690 /* Return the read-only data section associated with function DECL. */
692 section *
693 default_function_rodata_section (tree decl)
695 if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
697 const char *name = DECL_SECTION_NAME (decl);
699 if (DECL_COMDAT_GROUP (decl) && HAVE_COMDAT_GROUP)
701 const char *dot;
702 size_t len;
703 char* rname;
705 dot = strchr (name + 1, '.');
706 if (!dot)
707 dot = name;
708 len = strlen (dot) + 8;
709 rname = (char *) alloca (len);
711 strcpy (rname, ".rodata");
712 strcat (rname, dot);
713 return get_section (rname, SECTION_LINKONCE, decl);
715 /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo. */
716 else if (DECL_COMDAT_GROUP (decl)
717 && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
719 size_t len = strlen (name) + 1;
720 char *rname = (char *) alloca (len);
722 memcpy (rname, name, len);
723 rname[14] = 'r';
724 return get_section (rname, SECTION_LINKONCE, decl);
726 /* For .text.foo we want to use .rodata.foo. */
727 else if (flag_function_sections && flag_data_sections
728 && strncmp (name, ".text.", 6) == 0)
730 size_t len = strlen (name) + 1;
731 char *rname = (char *) alloca (len + 2);
733 memcpy (rname, ".rodata", 7);
734 memcpy (rname + 7, name + 5, len - 5);
735 return get_section (rname, 0, decl);
739 return readonly_data_section;
742 /* Return the read-only data section associated with function DECL
743 for targets where that section should be always the single
744 readonly data section. */
746 section *
747 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
749 return readonly_data_section;
752 /* Return the section to use for string merging. */
754 static section *
755 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
756 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
757 unsigned int flags ATTRIBUTE_UNUSED)
759 HOST_WIDE_INT len;
761 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
762 && TREE_CODE (decl) == STRING_CST
763 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
764 && align <= 256
765 && (len = int_size_in_bytes (TREE_TYPE (decl))) > 0
766 && TREE_STRING_LENGTH (decl) >= len)
768 enum machine_mode mode;
769 unsigned int modesize;
770 const char *str;
771 HOST_WIDE_INT i;
772 int j, unit;
773 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
774 char *name = (char *) alloca (strlen (prefix) + 30);
776 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
777 modesize = GET_MODE_BITSIZE (mode);
778 if (modesize >= 8 && modesize <= 256
779 && (modesize & (modesize - 1)) == 0)
781 if (align < modesize)
782 align = modesize;
784 str = TREE_STRING_POINTER (decl);
785 unit = GET_MODE_SIZE (mode);
787 /* Check for embedded NUL characters. */
788 for (i = 0; i < len; i += unit)
790 for (j = 0; j < unit; j++)
791 if (str[i + j] != '\0')
792 break;
793 if (j == unit)
794 break;
796 if (i == len - unit)
798 sprintf (name, "%s.str%d.%d", prefix,
799 modesize / 8, (int) (align / 8));
800 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
801 return get_section (name, flags, NULL);
806 return readonly_data_section;
809 /* Return the section to use for constant merging. */
811 section *
812 mergeable_constant_section (enum machine_mode mode ATTRIBUTE_UNUSED,
813 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
814 unsigned int flags ATTRIBUTE_UNUSED)
816 unsigned int modesize = GET_MODE_BITSIZE (mode);
818 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
819 && mode != VOIDmode
820 && mode != BLKmode
821 && modesize <= align
822 && align >= 8
823 && align <= 256
824 && (align & (align - 1)) == 0)
826 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
827 char *name = (char *) alloca (strlen (prefix) + 30);
829 sprintf (name, "%s.cst%d", prefix, (int) (align / 8));
830 flags |= (align / 8) | SECTION_MERGE;
831 return get_section (name, flags, NULL);
833 return readonly_data_section;
836 /* Given NAME, a putative register name, discard any customary prefixes. */
838 static const char *
839 strip_reg_name (const char *name)
841 #ifdef REGISTER_PREFIX
842 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
843 name += strlen (REGISTER_PREFIX);
844 #endif
845 if (name[0] == '%' || name[0] == '#')
846 name++;
847 return name;
850 /* The user has asked for a DECL to have a particular name. Set (or
851 change) it in such a way that we don't prefix an underscore to
852 it. */
853 void
854 set_user_assembler_name (tree decl, const char *name)
856 char *starred = (char *) alloca (strlen (name) + 2);
857 starred[0] = '*';
858 strcpy (starred + 1, name);
859 symtab->change_decl_assembler_name (decl, get_identifier (starred));
860 SET_DECL_RTL (decl, NULL_RTX);
863 /* Decode an `asm' spec for a declaration as a register name.
864 Return the register number, or -1 if nothing specified,
865 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
866 or -3 if ASMSPEC is `cc' and is not recognized,
867 or -4 if ASMSPEC is `memory' and is not recognized.
868 Accept an exact spelling or a decimal number.
869 Prefixes such as % are optional. */
872 decode_reg_name_and_count (const char *asmspec, int *pnregs)
874 /* Presume just one register is clobbered. */
875 *pnregs = 1;
877 if (asmspec != 0)
879 int i;
881 /* Get rid of confusing prefixes. */
882 asmspec = strip_reg_name (asmspec);
884 /* Allow a decimal number as a "register name". */
885 for (i = strlen (asmspec) - 1; i >= 0; i--)
886 if (! ISDIGIT (asmspec[i]))
887 break;
888 if (asmspec[0] != 0 && i < 0)
890 i = atoi (asmspec);
891 if (i < FIRST_PSEUDO_REGISTER && i >= 0)
892 return i;
893 else
894 return -2;
897 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
898 if (reg_names[i][0]
899 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
900 return i;
902 #ifdef OVERLAPPING_REGISTER_NAMES
904 static const struct
906 const char *const name;
907 const int number;
908 const int nregs;
909 } table[] = OVERLAPPING_REGISTER_NAMES;
911 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
912 if (table[i].name[0]
913 && ! strcmp (asmspec, table[i].name))
915 *pnregs = table[i].nregs;
916 return table[i].number;
919 #endif /* OVERLAPPING_REGISTER_NAMES */
921 #ifdef ADDITIONAL_REGISTER_NAMES
923 static const struct { const char *const name; const int number; } table[]
924 = ADDITIONAL_REGISTER_NAMES;
926 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
927 if (table[i].name[0]
928 && ! strcmp (asmspec, table[i].name))
929 return table[i].number;
931 #endif /* ADDITIONAL_REGISTER_NAMES */
933 if (!strcmp (asmspec, "memory"))
934 return -4;
936 if (!strcmp (asmspec, "cc"))
937 return -3;
939 return -2;
942 return -1;
946 decode_reg_name (const char *name)
948 int count;
949 return decode_reg_name_and_count (name, &count);
953 /* Return true if DECL's initializer is suitable for a BSS section. */
955 bool
956 bss_initializer_p (const_tree decl)
958 return (DECL_INITIAL (decl) == NULL
959 /* In LTO we have no errors in program; error_mark_node is used
960 to mark offlined constructors. */
961 || (DECL_INITIAL (decl) == error_mark_node
962 && !in_lto_p)
963 || (flag_zero_initialized_in_bss
964 /* Leave constant zeroes in .rodata so they
965 can be shared. */
966 && !TREE_READONLY (decl)
967 && initializer_zerop (DECL_INITIAL (decl))));
970 /* Compute the alignment of variable specified by DECL.
971 DONT_OUTPUT_DATA is from assemble_variable. */
973 void
974 align_variable (tree decl, bool dont_output_data)
976 unsigned int align = DECL_ALIGN (decl);
978 /* In the case for initialing an array whose length isn't specified,
979 where we have not yet been able to do the layout,
980 figure out the proper alignment now. */
981 if (dont_output_data && DECL_SIZE (decl) == 0
982 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
983 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
985 /* Some object file formats have a maximum alignment which they support.
986 In particular, a.out format supports a maximum alignment of 4. */
987 if (align > MAX_OFILE_ALIGNMENT)
989 error ("alignment of %q+D is greater than maximum object "
990 "file alignment %d", decl,
991 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
992 align = MAX_OFILE_ALIGNMENT;
995 if (! DECL_USER_ALIGN (decl))
997 #ifdef DATA_ABI_ALIGNMENT
998 unsigned int data_abi_align
999 = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1000 /* For backwards compatibility, don't assume the ABI alignment for
1001 TLS variables. */
1002 if (! DECL_THREAD_LOCAL_P (decl) || data_abi_align <= BITS_PER_WORD)
1003 align = data_abi_align;
1004 #endif
1006 /* On some machines, it is good to increase alignment sometimes.
1007 But as DECL_ALIGN is used both for actually emitting the variable
1008 and for code accessing the variable as guaranteed alignment, we
1009 can only increase the alignment if it is a performance optimization
1010 if the references to it must bind to the current definition. */
1011 if (decl_binds_to_current_def_p (decl)
1012 && !DECL_VIRTUAL_P (decl))
1014 #ifdef DATA_ALIGNMENT
1015 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1016 /* Don't increase alignment too much for TLS variables - TLS space
1017 is too precious. */
1018 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1019 align = data_align;
1020 #endif
1021 #ifdef CONSTANT_ALIGNMENT
1022 if (DECL_INITIAL (decl) != 0
1023 /* In LTO we have no errors in program; error_mark_node is used
1024 to mark offlined constructors. */
1025 && (in_lto_p || DECL_INITIAL (decl) != error_mark_node))
1027 unsigned int const_align
1028 = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
1029 /* Don't increase alignment too much for TLS variables - TLS
1030 space is too precious. */
1031 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1032 align = const_align;
1034 #endif
1038 /* Reset the alignment in case we have made it tighter, so we can benefit
1039 from it in get_pointer_alignment. */
1040 DECL_ALIGN (decl) = align;
1043 /* Return DECL_ALIGN (decl), possibly increased for optimization purposes
1044 beyond what align_variable returned. */
1046 static unsigned int
1047 get_variable_align (tree decl)
1049 unsigned int align = DECL_ALIGN (decl);
1051 /* For user aligned vars or static vars align_variable already did
1052 everything. */
1053 if (DECL_USER_ALIGN (decl) || !TREE_PUBLIC (decl))
1054 return align;
1056 #ifdef DATA_ABI_ALIGNMENT
1057 if (DECL_THREAD_LOCAL_P (decl))
1058 align = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1059 #endif
1061 /* For decls that bind to the current definition, align_variable
1062 did also everything, except for not assuming ABI required alignment
1063 of TLS variables. For other vars, increase the alignment here
1064 as an optimization. */
1065 if (!decl_binds_to_current_def_p (decl))
1067 /* On some machines, it is good to increase alignment sometimes. */
1068 #ifdef DATA_ALIGNMENT
1069 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1070 /* Don't increase alignment too much for TLS variables - TLS space
1071 is too precious. */
1072 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1073 align = data_align;
1074 #endif
1075 #ifdef CONSTANT_ALIGNMENT
1076 if (DECL_INITIAL (decl) != 0
1077 /* In LTO we have no errors in program; error_mark_node is used
1078 to mark offlined constructors. */
1079 && (in_lto_p || DECL_INITIAL (decl) != error_mark_node))
1081 unsigned int const_align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl),
1082 align);
1083 /* Don't increase alignment too much for TLS variables - TLS space
1084 is too precious. */
1085 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1086 align = const_align;
1088 #endif
1091 return align;
1094 /* Return the section into which the given VAR_DECL or CONST_DECL
1095 should be placed. PREFER_NOSWITCH_P is true if a noswitch
1096 section should be used wherever possible. */
1098 section *
1099 get_variable_section (tree decl, bool prefer_noswitch_p)
1101 addr_space_t as = ADDR_SPACE_GENERIC;
1102 int reloc;
1103 varpool_node *vnode = varpool_node::get (decl);
1104 if (vnode)
1106 vnode = vnode->ultimate_alias_target ();
1107 decl = vnode->decl;
1110 if (TREE_TYPE (decl) != error_mark_node)
1111 as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1113 /* We need the constructor to figure out reloc flag. */
1114 if (vnode)
1115 vnode->get_constructor ();
1117 if (DECL_COMMON (decl))
1119 /* If the decl has been given an explicit section name, or it resides
1120 in a non-generic address space, then it isn't common, and shouldn't
1121 be handled as such. */
1122 gcc_assert (DECL_SECTION_NAME (decl) == NULL
1123 && ADDR_SPACE_GENERIC_P (as));
1124 if (DECL_THREAD_LOCAL_P (decl))
1125 return tls_comm_section;
1126 else if (TREE_PUBLIC (decl) && bss_initializer_p (decl))
1127 return comm_section;
1130 if (DECL_INITIAL (decl) == error_mark_node)
1131 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1132 else if (DECL_INITIAL (decl))
1133 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1134 else
1135 reloc = 0;
1137 resolve_unique_section (decl, reloc, flag_data_sections);
1138 if (IN_NAMED_SECTION (decl))
1139 return get_named_section (decl, NULL, reloc);
1141 if (ADDR_SPACE_GENERIC_P (as)
1142 && !DECL_THREAD_LOCAL_P (decl)
1143 && !(prefer_noswitch_p && targetm.have_switchable_bss_sections)
1144 && bss_initializer_p (decl))
1146 if (!TREE_PUBLIC (decl)
1147 && !((flag_sanitize & SANITIZE_ADDRESS)
1148 && asan_protect_global (decl)))
1149 return lcomm_section;
1150 if (bss_noswitch_section)
1151 return bss_noswitch_section;
1154 return targetm.asm_out.select_section (decl, reloc,
1155 get_variable_align (decl));
1158 /* Return the block into which object_block DECL should be placed. */
1160 static struct object_block *
1161 get_block_for_decl (tree decl)
1163 section *sect;
1165 if (TREE_CODE (decl) == VAR_DECL)
1167 /* The object must be defined in this translation unit. */
1168 if (DECL_EXTERNAL (decl))
1169 return NULL;
1171 /* There's no point using object blocks for something that is
1172 isolated by definition. */
1173 if (DECL_COMDAT_GROUP (decl))
1174 return NULL;
1177 /* We can only calculate block offsets if the decl has a known
1178 constant size. */
1179 if (DECL_SIZE_UNIT (decl) == NULL)
1180 return NULL;
1181 if (!tree_fits_uhwi_p (DECL_SIZE_UNIT (decl)))
1182 return NULL;
1184 /* Find out which section should contain DECL. We cannot put it into
1185 an object block if it requires a standalone definition. */
1186 if (TREE_CODE (decl) == VAR_DECL)
1187 align_variable (decl, 0);
1188 sect = get_variable_section (decl, true);
1189 if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
1190 return NULL;
1192 return get_block_for_section (sect);
1195 /* Make sure block symbol SYMBOL is in block BLOCK. */
1197 static void
1198 change_symbol_block (rtx symbol, struct object_block *block)
1200 if (block != SYMBOL_REF_BLOCK (symbol))
1202 gcc_assert (SYMBOL_REF_BLOCK_OFFSET (symbol) < 0);
1203 SYMBOL_REF_BLOCK (symbol) = block;
1207 /* Return true if it is possible to put DECL in an object_block. */
1209 static bool
1210 use_blocks_for_decl_p (tree decl)
1212 struct symtab_node *snode;
1214 /* Only data DECLs can be placed into object blocks. */
1215 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != CONST_DECL)
1216 return false;
1218 /* Detect decls created by dw2_force_const_mem. Such decls are
1219 special because DECL_INITIAL doesn't specify the decl's true value.
1220 dw2_output_indirect_constants will instead call assemble_variable
1221 with dont_output_data set to 1 and then print the contents itself. */
1222 if (DECL_INITIAL (decl) == decl)
1223 return false;
1225 /* If this decl is an alias, then we don't want to emit a
1226 definition. */
1227 if (TREE_CODE (decl) == VAR_DECL
1228 && (snode = symtab_node::get (decl)) != NULL
1229 && snode->alias)
1230 return false;
1232 return targetm.use_blocks_for_decl_p (decl);
1235 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
1236 have static storage duration. In other words, it should not be an
1237 automatic variable, including PARM_DECLs.
1239 There is, however, one exception: this function handles variables
1240 explicitly placed in a particular register by the user.
1242 This is never called for PARM_DECL nodes. */
1244 void
1245 make_decl_rtl (tree decl)
1247 const char *name = 0;
1248 int reg_number;
1249 rtx x;
1251 /* Check that we are not being given an automatic variable. */
1252 gcc_assert (TREE_CODE (decl) != PARM_DECL
1253 && TREE_CODE (decl) != RESULT_DECL);
1255 /* A weak alias has TREE_PUBLIC set but not the other bits. */
1256 gcc_assert (TREE_CODE (decl) != VAR_DECL
1257 || TREE_STATIC (decl)
1258 || TREE_PUBLIC (decl)
1259 || DECL_EXTERNAL (decl)
1260 || DECL_REGISTER (decl));
1262 /* And that we were not given a type or a label. */
1263 gcc_assert (TREE_CODE (decl) != TYPE_DECL
1264 && TREE_CODE (decl) != LABEL_DECL);
1266 /* For a duplicate declaration, we can be called twice on the
1267 same DECL node. Don't discard the RTL already made. */
1268 if (DECL_RTL_SET_P (decl))
1270 /* If the old RTL had the wrong mode, fix the mode. */
1271 x = DECL_RTL (decl);
1272 if (GET_MODE (x) != DECL_MODE (decl))
1273 SET_DECL_RTL (decl, adjust_address_nv (x, DECL_MODE (decl), 0));
1275 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1276 return;
1278 /* ??? Another way to do this would be to maintain a hashed
1279 table of such critters. Instead of adding stuff to a DECL
1280 to give certain attributes to it, we could use an external
1281 hash map from DECL to set of attributes. */
1283 /* Let the target reassign the RTL if it wants.
1284 This is necessary, for example, when one machine specific
1285 decl attribute overrides another. */
1286 targetm.encode_section_info (decl, DECL_RTL (decl), false);
1288 /* If the symbol has a SYMBOL_REF_BLOCK field, update it based
1289 on the new decl information. */
1290 if (MEM_P (x)
1291 && GET_CODE (XEXP (x, 0)) == SYMBOL_REF
1292 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (x, 0)))
1293 change_symbol_block (XEXP (x, 0), get_block_for_decl (decl));
1295 return;
1298 /* If this variable belongs to the global constant pool, retrieve the
1299 pre-computed RTL or recompute it in LTO mode. */
1300 if (TREE_CODE (decl) == VAR_DECL && DECL_IN_CONSTANT_POOL (decl))
1302 SET_DECL_RTL (decl, output_constant_def (DECL_INITIAL (decl), 1));
1303 return;
1306 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
1308 if (name[0] != '*' && TREE_CODE (decl) != FUNCTION_DECL
1309 && DECL_REGISTER (decl))
1311 error ("register name not specified for %q+D", decl);
1313 else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1315 const char *asmspec = name+1;
1316 enum machine_mode mode = DECL_MODE (decl);
1317 reg_number = decode_reg_name (asmspec);
1318 /* First detect errors in declaring global registers. */
1319 if (reg_number == -1)
1320 error ("register name not specified for %q+D", decl);
1321 else if (reg_number < 0)
1322 error ("invalid register name for %q+D", decl);
1323 else if (mode == BLKmode)
1324 error ("data type of %q+D isn%'t suitable for a register",
1325 decl);
1326 else if (!in_hard_reg_set_p (accessible_reg_set, mode, reg_number))
1327 error ("the register specified for %q+D cannot be accessed"
1328 " by the current target", decl);
1329 else if (!in_hard_reg_set_p (operand_reg_set, mode, reg_number))
1330 error ("the register specified for %q+D is not general enough"
1331 " to be used as a register variable", decl);
1332 else if (!HARD_REGNO_MODE_OK (reg_number, mode))
1333 error ("register specified for %q+D isn%'t suitable for data type",
1334 decl);
1335 /* Now handle properly declared static register variables. */
1336 else
1338 int nregs;
1340 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
1342 DECL_INITIAL (decl) = 0;
1343 error ("global register variable has initial value");
1345 if (TREE_THIS_VOLATILE (decl))
1346 warning (OPT_Wvolatile_register_var,
1347 "optimization may eliminate reads and/or "
1348 "writes to register variables");
1350 /* If the user specified one of the eliminables registers here,
1351 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
1352 confused with that register and be eliminated. This usage is
1353 somewhat suspect... */
1355 SET_DECL_RTL (decl, gen_rtx_raw_REG (mode, reg_number));
1356 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
1357 REG_USERVAR_P (DECL_RTL (decl)) = 1;
1359 if (TREE_STATIC (decl))
1361 /* Make this register global, so not usable for anything
1362 else. */
1363 #ifdef ASM_DECLARE_REGISTER_GLOBAL
1364 name = IDENTIFIER_POINTER (DECL_NAME (decl));
1365 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
1366 #endif
1367 nregs = hard_regno_nregs[reg_number][mode];
1368 while (nregs > 0)
1369 globalize_reg (decl, reg_number + --nregs);
1372 /* As a register variable, it has no section. */
1373 return;
1375 /* Avoid internal errors from invalid register
1376 specifications. */
1377 SET_DECL_ASSEMBLER_NAME (decl, NULL_TREE);
1378 DECL_HARD_REGISTER (decl) = 0;
1379 return;
1381 /* Now handle ordinary static variables and functions (in memory).
1382 Also handle vars declared register invalidly. */
1383 else if (name[0] == '*')
1385 #ifdef REGISTER_PREFIX
1386 if (strlen (REGISTER_PREFIX) != 0)
1388 reg_number = decode_reg_name (name);
1389 if (reg_number >= 0 || reg_number == -3)
1390 error ("register name given for non-register variable %q+D", decl);
1392 #endif
1395 /* Specifying a section attribute on a variable forces it into a
1396 non-.bss section, and thus it cannot be common. */
1397 /* FIXME: In general this code should not be necessary because
1398 visibility pass is doing the same work. But notice_global_symbol
1399 is called early and it needs to make DECL_RTL to get the name.
1400 we take care of recomputing the DECL_RTL after visibility is changed. */
1401 if (TREE_CODE (decl) == VAR_DECL
1402 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl))
1403 && DECL_SECTION_NAME (decl) != NULL
1404 && DECL_INITIAL (decl) == NULL_TREE
1405 && DECL_COMMON (decl))
1406 DECL_COMMON (decl) = 0;
1408 /* Variables can't be both common and weak. */
1409 if (TREE_CODE (decl) == VAR_DECL && DECL_WEAK (decl))
1410 DECL_COMMON (decl) = 0;
1412 if (use_object_blocks_p () && use_blocks_for_decl_p (decl))
1413 x = create_block_symbol (name, get_block_for_decl (decl), -1);
1414 else
1416 enum machine_mode address_mode = Pmode;
1417 if (TREE_TYPE (decl) != error_mark_node)
1419 addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1420 address_mode = targetm.addr_space.address_mode (as);
1422 x = gen_rtx_SYMBOL_REF (address_mode, name);
1424 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
1425 SET_SYMBOL_REF_DECL (x, decl);
1427 x = gen_rtx_MEM (DECL_MODE (decl), x);
1428 if (TREE_CODE (decl) != FUNCTION_DECL)
1429 set_mem_attributes (x, decl, 1);
1430 SET_DECL_RTL (decl, x);
1432 /* Optionally set flags or add text to the name to record information
1433 such as that it is a function name.
1434 If the name is changed, the macro ASM_OUTPUT_LABELREF
1435 will have to know how to strip this information. */
1436 targetm.encode_section_info (decl, DECL_RTL (decl), true);
1439 /* Like make_decl_rtl, but inhibit creation of new alias sets when
1440 calling make_decl_rtl. Also, reset DECL_RTL before returning the
1441 rtl. */
1444 make_decl_rtl_for_debug (tree decl)
1446 unsigned int save_aliasing_flag;
1447 rtx rtl;
1449 if (DECL_RTL_SET_P (decl))
1450 return DECL_RTL (decl);
1452 /* Kludge alert! Somewhere down the call chain, make_decl_rtl will
1453 call new_alias_set. If running with -fcompare-debug, sometimes
1454 we do not want to create alias sets that will throw the alias
1455 numbers off in the comparison dumps. So... clearing
1456 flag_strict_aliasing will keep new_alias_set() from creating a
1457 new set. */
1458 save_aliasing_flag = flag_strict_aliasing;
1459 flag_strict_aliasing = 0;
1461 rtl = DECL_RTL (decl);
1462 /* Reset DECL_RTL back, as various parts of the compiler expects
1463 DECL_RTL set meaning it is actually going to be output. */
1464 SET_DECL_RTL (decl, NULL);
1466 flag_strict_aliasing = save_aliasing_flag;
1467 return rtl;
1470 /* Output a string of literal assembler code
1471 for an `asm' keyword used between functions. */
1473 void
1474 assemble_asm (tree string)
1476 const char *p;
1477 app_enable ();
1479 if (TREE_CODE (string) == ADDR_EXPR)
1480 string = TREE_OPERAND (string, 0);
1482 p = TREE_STRING_POINTER (string);
1483 fprintf (asm_out_file, "%s%s\n", p[0] == '\t' ? "" : "\t", p);
1486 /* Write the address of the entity given by SYMBOL to SEC. */
1487 void
1488 assemble_addr_to_section (rtx symbol, section *sec)
1490 switch_to_section (sec);
1491 assemble_align (POINTER_SIZE);
1492 assemble_integer (symbol, POINTER_SIZE_UNITS, POINTER_SIZE, 1);
1495 /* Return the numbered .ctors.N (if CONSTRUCTOR_P) or .dtors.N (if
1496 not) section for PRIORITY. */
1497 section *
1498 get_cdtor_priority_section (int priority, bool constructor_p)
1500 char buf[16];
1502 /* ??? This only works reliably with the GNU linker. */
1503 sprintf (buf, "%s.%.5u",
1504 constructor_p ? ".ctors" : ".dtors",
1505 /* Invert the numbering so the linker puts us in the proper
1506 order; constructors are run from right to left, and the
1507 linker sorts in increasing order. */
1508 MAX_INIT_PRIORITY - priority);
1509 return get_section (buf, SECTION_WRITE, NULL);
1512 void
1513 default_named_section_asm_out_destructor (rtx symbol, int priority)
1515 section *sec;
1517 if (priority != DEFAULT_INIT_PRIORITY)
1518 sec = get_cdtor_priority_section (priority,
1519 /*constructor_p=*/false);
1520 else
1521 sec = get_section (".dtors", SECTION_WRITE, NULL);
1523 assemble_addr_to_section (symbol, sec);
1526 #ifdef DTORS_SECTION_ASM_OP
1527 void
1528 default_dtor_section_asm_out_destructor (rtx symbol,
1529 int priority ATTRIBUTE_UNUSED)
1531 assemble_addr_to_section (symbol, dtors_section);
1533 #endif
1535 void
1536 default_named_section_asm_out_constructor (rtx symbol, int priority)
1538 section *sec;
1540 if (priority != DEFAULT_INIT_PRIORITY)
1541 sec = get_cdtor_priority_section (priority,
1542 /*constructor_p=*/true);
1543 else
1544 sec = get_section (".ctors", SECTION_WRITE, NULL);
1546 assemble_addr_to_section (symbol, sec);
1549 #ifdef CTORS_SECTION_ASM_OP
1550 void
1551 default_ctor_section_asm_out_constructor (rtx symbol,
1552 int priority ATTRIBUTE_UNUSED)
1554 assemble_addr_to_section (symbol, ctors_section);
1556 #endif
1558 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1559 a nonzero value if the constant pool should be output before the
1560 start of the function, or a zero value if the pool should output
1561 after the end of the function. The default is to put it before the
1562 start. */
1564 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1565 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1566 #endif
1568 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1569 to be output to assembler.
1570 Set first_global_object_name and weak_global_object_name as appropriate. */
1572 void
1573 notice_global_symbol (tree decl)
1575 const char **type = &first_global_object_name;
1577 if (first_global_object_name
1578 || !TREE_PUBLIC (decl)
1579 || DECL_EXTERNAL (decl)
1580 || !DECL_NAME (decl)
1581 || (TREE_CODE (decl) != FUNCTION_DECL
1582 && (TREE_CODE (decl) != VAR_DECL
1583 || (DECL_COMMON (decl)
1584 && (DECL_INITIAL (decl) == 0
1585 || DECL_INITIAL (decl) == error_mark_node))))
1586 || !MEM_P (DECL_RTL (decl)))
1587 return;
1589 /* We win when global object is found, but it is useful to know about weak
1590 symbol as well so we can produce nicer unique names. */
1591 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl) || flag_shlib)
1592 type = &weak_global_object_name;
1594 if (!*type)
1596 const char *p;
1597 const char *name;
1598 rtx decl_rtl = DECL_RTL (decl);
1600 p = targetm.strip_name_encoding (XSTR (XEXP (decl_rtl, 0), 0));
1601 name = ggc_strdup (p);
1603 *type = name;
1607 /* If not using flag_reorder_blocks_and_partition, decide early whether the
1608 current function goes into the cold section, so that targets can use
1609 current_function_section during RTL expansion. DECL describes the
1610 function. */
1612 void
1613 decide_function_section (tree decl)
1615 first_function_block_is_cold = false;
1617 if (flag_reorder_blocks_and_partition)
1618 /* We will decide in assemble_start_function. */
1619 return;
1621 if (DECL_SECTION_NAME (decl))
1623 struct cgraph_node *node = cgraph_node::get (current_function_decl);
1624 /* Calls to function_section rely on first_function_block_is_cold
1625 being accurate. */
1626 first_function_block_is_cold = (node
1627 && node->frequency
1628 == NODE_FREQUENCY_UNLIKELY_EXECUTED);
1631 in_cold_section_p = first_function_block_is_cold;
1634 /* Output assembler code for the constant pool of a function and associated
1635 with defining the name of the function. DECL describes the function.
1636 NAME is the function's name. For the constant pool, we use the current
1637 constant pool data. */
1639 void
1640 assemble_start_function (tree decl, const char *fnname)
1642 int align;
1643 char tmp_label[100];
1644 bool hot_label_written = false;
1646 if (flag_reorder_blocks_and_partition)
1648 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTB", const_labelno);
1649 crtl->subsections.hot_section_label = ggc_strdup (tmp_label);
1650 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDB", const_labelno);
1651 crtl->subsections.cold_section_label = ggc_strdup (tmp_label);
1652 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTE", const_labelno);
1653 crtl->subsections.hot_section_end_label = ggc_strdup (tmp_label);
1654 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDE", const_labelno);
1655 crtl->subsections.cold_section_end_label = ggc_strdup (tmp_label);
1656 const_labelno++;
1658 else
1660 crtl->subsections.hot_section_label = NULL;
1661 crtl->subsections.cold_section_label = NULL;
1662 crtl->subsections.hot_section_end_label = NULL;
1663 crtl->subsections.cold_section_end_label = NULL;
1666 /* The following code does not need preprocessing in the assembler. */
1668 app_disable ();
1670 if (CONSTANT_POOL_BEFORE_FUNCTION)
1671 output_constant_pool (fnname, decl);
1673 /* Make sure the not and cold text (code) sections are properly
1674 aligned. This is necessary here in the case where the function
1675 has both hot and cold sections, because we don't want to re-set
1676 the alignment when the section switch happens mid-function. */
1678 if (flag_reorder_blocks_and_partition)
1680 first_function_block_is_cold = false;
1682 switch_to_section (unlikely_text_section ());
1683 assemble_align (DECL_ALIGN (decl));
1684 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_label);
1686 /* When the function starts with a cold section, we need to explicitly
1687 align the hot section and write out the hot section label.
1688 But if the current function is a thunk, we do not have a CFG. */
1689 if (!cfun->is_thunk
1690 && BB_PARTITION (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) == BB_COLD_PARTITION)
1692 switch_to_section (text_section);
1693 assemble_align (DECL_ALIGN (decl));
1694 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1695 hot_label_written = true;
1696 first_function_block_is_cold = true;
1698 in_cold_section_p = first_function_block_is_cold;
1702 /* Switch to the correct text section for the start of the function. */
1704 switch_to_section (function_section (decl));
1705 if (flag_reorder_blocks_and_partition
1706 && !hot_label_written)
1707 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1709 /* Tell assembler to move to target machine's alignment for functions. */
1710 align = floor_log2 (DECL_ALIGN (decl) / BITS_PER_UNIT);
1711 if (align > 0)
1713 ASM_OUTPUT_ALIGN (asm_out_file, align);
1716 /* Handle a user-specified function alignment.
1717 Note that we still need to align to DECL_ALIGN, as above,
1718 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1719 if (! DECL_USER_ALIGN (decl)
1720 && align_functions_log > align
1721 && optimize_function_for_speed_p (cfun))
1723 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1724 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1725 align_functions_log, align_functions - 1);
1726 #else
1727 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1728 #endif
1731 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1732 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1733 #endif
1735 if (!DECL_IGNORED_P (decl))
1736 (*debug_hooks->begin_function) (decl);
1738 /* Make function name accessible from other files, if appropriate. */
1740 if (TREE_PUBLIC (decl))
1742 notice_global_symbol (decl);
1744 globalize_decl (decl);
1746 maybe_assemble_visibility (decl);
1749 if (DECL_PRESERVE_P (decl))
1750 targetm.asm_out.mark_decl_preserved (fnname);
1752 /* Do any machine/system dependent processing of the function name. */
1753 #ifdef ASM_DECLARE_FUNCTION_NAME
1754 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1755 #else
1756 /* Standard thing is just output label for the function. */
1757 ASM_OUTPUT_FUNCTION_LABEL (asm_out_file, fnname, current_function_decl);
1758 #endif /* ASM_DECLARE_FUNCTION_NAME */
1760 if (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (decl)))
1761 saw_no_split_stack = true;
1764 /* Output assembler code associated with defining the size of the
1765 function. DECL describes the function. NAME is the function's name. */
1767 void
1768 assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED)
1770 #ifdef ASM_DECLARE_FUNCTION_SIZE
1771 /* We could have switched section in the middle of the function. */
1772 if (flag_reorder_blocks_and_partition)
1773 switch_to_section (function_section (decl));
1774 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1775 #endif
1776 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1778 output_constant_pool (fnname, decl);
1779 switch_to_section (function_section (decl)); /* need to switch back */
1781 /* Output labels for end of hot/cold text sections (to be used by
1782 debug info.) */
1783 if (flag_reorder_blocks_and_partition)
1785 section *save_text_section;
1787 save_text_section = in_section;
1788 switch_to_section (unlikely_text_section ());
1789 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label);
1790 if (first_function_block_is_cold)
1791 switch_to_section (text_section);
1792 else
1793 switch_to_section (function_section (decl));
1794 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label);
1795 switch_to_section (save_text_section);
1799 /* Assemble code to leave SIZE bytes of zeros. */
1801 void
1802 assemble_zeros (unsigned HOST_WIDE_INT size)
1804 /* Do no output if -fsyntax-only. */
1805 if (flag_syntax_only)
1806 return;
1808 #ifdef ASM_NO_SKIP_IN_TEXT
1809 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1810 so we must output 0s explicitly in the text section. */
1811 if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0)
1813 unsigned HOST_WIDE_INT i;
1814 for (i = 0; i < size; i++)
1815 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1817 else
1818 #endif
1819 if (size > 0)
1820 ASM_OUTPUT_SKIP (asm_out_file, size);
1823 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1825 void
1826 assemble_align (int align)
1828 if (align > BITS_PER_UNIT)
1830 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1834 /* Assemble a string constant with the specified C string as contents. */
1836 void
1837 assemble_string (const char *p, int size)
1839 int pos = 0;
1840 int maximum = 2000;
1842 /* If the string is very long, split it up. */
1844 while (pos < size)
1846 int thissize = size - pos;
1847 if (thissize > maximum)
1848 thissize = maximum;
1850 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1852 pos += thissize;
1853 p += thissize;
1858 /* A noswitch_section_callback for lcomm_section. */
1860 static bool
1861 emit_local (tree decl ATTRIBUTE_UNUSED,
1862 const char *name ATTRIBUTE_UNUSED,
1863 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1864 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1866 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1867 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name,
1868 size, DECL_ALIGN (decl));
1869 return true;
1870 #elif defined ASM_OUTPUT_ALIGNED_LOCAL
1871 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, DECL_ALIGN (decl));
1872 return true;
1873 #else
1874 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1875 return false;
1876 #endif
1879 /* A noswitch_section_callback for bss_noswitch_section. */
1881 #if defined ASM_OUTPUT_ALIGNED_BSS
1882 static bool
1883 emit_bss (tree decl ATTRIBUTE_UNUSED,
1884 const char *name ATTRIBUTE_UNUSED,
1885 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1886 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1888 #if defined ASM_OUTPUT_ALIGNED_BSS
1889 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size,
1890 get_variable_align (decl));
1891 return true;
1892 #endif
1894 #endif
1896 /* A noswitch_section_callback for comm_section. */
1898 static bool
1899 emit_common (tree decl ATTRIBUTE_UNUSED,
1900 const char *name ATTRIBUTE_UNUSED,
1901 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1902 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1904 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1905 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name,
1906 size, get_variable_align (decl));
1907 return true;
1908 #elif defined ASM_OUTPUT_ALIGNED_COMMON
1909 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size,
1910 get_variable_align (decl));
1911 return true;
1912 #else
1913 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
1914 return false;
1915 #endif
1918 /* A noswitch_section_callback for tls_comm_section. */
1920 static bool
1921 emit_tls_common (tree decl ATTRIBUTE_UNUSED,
1922 const char *name ATTRIBUTE_UNUSED,
1923 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1924 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1926 #ifdef ASM_OUTPUT_TLS_COMMON
1927 ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size);
1928 return true;
1929 #else
1930 sorry ("thread-local COMMON data not implemented");
1931 return true;
1932 #endif
1935 /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT.
1936 NAME is the name of DECL's SYMBOL_REF. */
1938 static void
1939 assemble_noswitch_variable (tree decl, const char *name, section *sect,
1940 unsigned int align)
1942 unsigned HOST_WIDE_INT size, rounded;
1944 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
1945 rounded = size;
1947 if ((flag_sanitize & SANITIZE_ADDRESS) && asan_protect_global (decl))
1948 size += asan_red_zone_size (size);
1950 /* Don't allocate zero bytes of common,
1951 since that means "undefined external" in the linker. */
1952 if (size == 0)
1953 rounded = 1;
1955 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1956 so that each uninitialized object starts on such a boundary. */
1957 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
1958 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1959 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1961 if (!sect->noswitch.callback (decl, name, size, rounded)
1962 && (unsigned HOST_WIDE_INT) (align / BITS_PER_UNIT) > rounded)
1963 error ("requested alignment for %q+D is greater than "
1964 "implemented alignment of %wu", decl, rounded);
1967 /* A subroutine of assemble_variable. Output the label and contents of
1968 DECL, whose address is a SYMBOL_REF with name NAME. DONT_OUTPUT_DATA
1969 is as for assemble_variable. */
1971 static void
1972 assemble_variable_contents (tree decl, const char *name,
1973 bool dont_output_data)
1975 /* Do any machine/system dependent processing of the object. */
1976 #ifdef ASM_DECLARE_OBJECT_NAME
1977 last_assemble_variable_decl = decl;
1978 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
1979 #else
1980 /* Standard thing is just output label for the object. */
1981 ASM_OUTPUT_LABEL (asm_out_file, name);
1982 #endif /* ASM_DECLARE_OBJECT_NAME */
1984 if (!dont_output_data)
1986 /* Caller is supposed to use varpool_get_constructor when it wants
1987 to output the body. */
1988 gcc_assert (!in_lto_p || DECL_INITIAL (decl) != error_mark_node);
1989 if (DECL_INITIAL (decl)
1990 && DECL_INITIAL (decl) != error_mark_node
1991 && !initializer_zerop (DECL_INITIAL (decl)))
1992 /* Output the actual data. */
1993 output_constant (DECL_INITIAL (decl),
1994 tree_to_uhwi (DECL_SIZE_UNIT (decl)),
1995 get_variable_align (decl));
1996 else
1997 /* Leave space for it. */
1998 assemble_zeros (tree_to_uhwi (DECL_SIZE_UNIT (decl)));
2002 /* Assemble everything that is needed for a variable or function declaration.
2003 Not used for automatic variables, and not used for function definitions.
2004 Should not be called for variables of incomplete structure type.
2006 TOP_LEVEL is nonzero if this variable has file scope.
2007 AT_END is nonzero if this is the special handling, at end of compilation,
2008 to define things that have had only tentative definitions.
2009 DONT_OUTPUT_DATA if nonzero means don't actually output the
2010 initial value (that will be done by the caller). */
2012 void
2013 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
2014 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
2016 const char *name;
2017 rtx decl_rtl, symbol;
2018 section *sect;
2019 unsigned int align;
2020 bool asan_protected = false;
2022 /* This function is supposed to handle VARIABLES. Ensure we have one. */
2023 gcc_assert (TREE_CODE (decl) == VAR_DECL);
2025 /* Emulated TLS had better not get this far. */
2026 gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl));
2028 last_assemble_variable_decl = 0;
2030 /* Normally no need to say anything here for external references,
2031 since assemble_external is called by the language-specific code
2032 when a declaration is first seen. */
2034 if (DECL_EXTERNAL (decl))
2035 return;
2037 /* Do nothing for global register variables. */
2038 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
2040 TREE_ASM_WRITTEN (decl) = 1;
2041 return;
2044 /* If type was incomplete when the variable was declared,
2045 see if it is complete now. */
2047 if (DECL_SIZE (decl) == 0)
2048 layout_decl (decl, 0);
2050 /* Still incomplete => don't allocate it; treat the tentative defn
2051 (which is what it must have been) as an `extern' reference. */
2053 if (!dont_output_data && DECL_SIZE (decl) == 0)
2055 error ("storage size of %q+D isn%'t known", decl);
2056 TREE_ASM_WRITTEN (decl) = 1;
2057 return;
2060 /* The first declaration of a variable that comes through this function
2061 decides whether it is global (in C, has external linkage)
2062 or local (in C, has internal linkage). So do nothing more
2063 if this function has already run. */
2065 if (TREE_ASM_WRITTEN (decl))
2066 return;
2068 /* Make sure targetm.encode_section_info is invoked before we set
2069 ASM_WRITTEN. */
2070 decl_rtl = DECL_RTL (decl);
2072 TREE_ASM_WRITTEN (decl) = 1;
2074 /* Do no output if -fsyntax-only. */
2075 if (flag_syntax_only)
2076 return;
2078 if (! dont_output_data
2079 && ! valid_constant_size_p (DECL_SIZE_UNIT (decl)))
2081 error ("size of variable %q+D is too large", decl);
2082 return;
2085 gcc_assert (MEM_P (decl_rtl));
2086 gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF);
2087 symbol = XEXP (decl_rtl, 0);
2089 /* If this symbol belongs to the tree constant pool, output the constant
2090 if it hasn't already been written. */
2091 if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
2093 tree decl = SYMBOL_REF_DECL (symbol);
2094 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
2095 output_constant_def_contents (symbol);
2096 return;
2099 app_disable ();
2101 name = XSTR (symbol, 0);
2102 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
2103 notice_global_symbol (decl);
2105 /* Compute the alignment of this data. */
2107 align_variable (decl, dont_output_data);
2109 if ((flag_sanitize & SANITIZE_ADDRESS)
2110 && asan_protect_global (decl))
2112 asan_protected = true;
2113 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
2114 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
2117 set_mem_align (decl_rtl, DECL_ALIGN (decl));
2119 align = get_variable_align (decl);
2121 if (TREE_PUBLIC (decl))
2122 maybe_assemble_visibility (decl);
2124 if (DECL_PRESERVE_P (decl))
2125 targetm.asm_out.mark_decl_preserved (name);
2127 /* First make the assembler name(s) global if appropriate. */
2128 sect = get_variable_section (decl, false);
2129 if (TREE_PUBLIC (decl)
2130 && (sect->common.flags & SECTION_COMMON) == 0)
2131 globalize_decl (decl);
2133 /* Output any data that we will need to use the address of. */
2134 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
2135 output_addressed_constants (DECL_INITIAL (decl));
2137 /* dbxout.c needs to know this. */
2138 if (sect && (sect->common.flags & SECTION_CODE) != 0)
2139 DECL_IN_TEXT_SECTION (decl) = 1;
2141 /* If the decl is part of an object_block, make sure that the decl
2142 has been positioned within its block, but do not write out its
2143 definition yet. output_object_blocks will do that later. */
2144 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
2146 gcc_assert (!dont_output_data);
2147 place_block_symbol (symbol);
2149 else if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
2150 assemble_noswitch_variable (decl, name, sect, align);
2151 else
2153 /* The following bit of code ensures that vtable_map
2154 variables are not only in the comdat section, but that
2155 each variable has its own unique comdat name. If this
2156 code is removed, the variables end up in the same section
2157 with a single comdat name.
2159 FIXME: resolve_unique_section needs to deal better with
2160 decls with both DECL_SECTION_NAME and DECL_ONE_ONLY. Once
2161 that is fixed, this if-else statement can be replaced with
2162 a single call to "switch_to_section (sect)". */
2163 if (sect->named.name
2164 && (strcmp (sect->named.name, ".vtable_map_vars") == 0))
2166 #if defined (OBJECT_FORMAT_ELF)
2167 targetm.asm_out.named_section (sect->named.name,
2168 sect->named.common.flags
2169 | SECTION_LINKONCE,
2170 DECL_NAME (decl));
2171 in_section = sect;
2172 #else
2173 switch_to_section (sect);
2174 #endif
2176 else
2177 switch_to_section (sect);
2178 if (align > BITS_PER_UNIT)
2179 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2180 assemble_variable_contents (decl, name, dont_output_data);
2181 if (asan_protected)
2183 unsigned HOST_WIDE_INT int size
2184 = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2185 assemble_zeros (asan_red_zone_size (size));
2191 /* Given a function declaration (FN_DECL), this function assembles the
2192 function into the .preinit_array section. */
2194 void
2195 assemble_vtv_preinit_initializer (tree fn_decl)
2197 section *sect;
2198 unsigned flags = SECTION_WRITE;
2199 rtx symbol = XEXP (DECL_RTL (fn_decl), 0);
2201 flags |= SECTION_NOTYPE;
2202 sect = get_section (".preinit_array", flags, fn_decl);
2203 switch_to_section (sect);
2204 assemble_addr_to_section (symbol, sect);
2207 /* Return 1 if type TYPE contains any pointers. */
2209 static int
2210 contains_pointers_p (tree type)
2212 switch (TREE_CODE (type))
2214 case POINTER_TYPE:
2215 case REFERENCE_TYPE:
2216 /* I'm not sure whether OFFSET_TYPE needs this treatment,
2217 so I'll play safe and return 1. */
2218 case OFFSET_TYPE:
2219 return 1;
2221 case RECORD_TYPE:
2222 case UNION_TYPE:
2223 case QUAL_UNION_TYPE:
2225 tree fields;
2226 /* For a type that has fields, see if the fields have pointers. */
2227 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2228 if (TREE_CODE (fields) == FIELD_DECL
2229 && contains_pointers_p (TREE_TYPE (fields)))
2230 return 1;
2231 return 0;
2234 case ARRAY_TYPE:
2235 /* An array type contains pointers if its element type does. */
2236 return contains_pointers_p (TREE_TYPE (type));
2238 default:
2239 return 0;
2243 /* We delay assemble_external processing until
2244 the compilation unit is finalized. This is the best we can do for
2245 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2246 it all the way to final. See PR 17982 for further discussion. */
2247 static GTY(()) tree pending_assemble_externals;
2249 #ifdef ASM_OUTPUT_EXTERNAL
2250 /* Some targets delay some output to final using TARGET_ASM_FILE_END.
2251 As a result, assemble_external can be called after the list of externals
2252 is processed and the pointer set destroyed. */
2253 static bool pending_assemble_externals_processed;
2255 /* Avoid O(external_decls**2) lookups in the pending_assemble_externals
2256 TREE_LIST in assemble_external. */
2257 static hash_set<tree> *pending_assemble_externals_set;
2259 /* True if DECL is a function decl for which no out-of-line copy exists.
2260 It is assumed that DECL's assembler name has been set. */
2262 static bool
2263 incorporeal_function_p (tree decl)
2265 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
2267 const char *name;
2269 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2270 && (DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA
2271 || DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA_WITH_ALIGN))
2272 return true;
2274 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2275 /* Atomic or sync builtins which have survived this far will be
2276 resolved externally and therefore are not incorporeal. */
2277 if (strncmp (name, "__builtin_", 10) == 0)
2278 return true;
2280 return false;
2283 /* Actually do the tests to determine if this is necessary, and invoke
2284 ASM_OUTPUT_EXTERNAL. */
2285 static void
2286 assemble_external_real (tree decl)
2288 rtx rtl = DECL_RTL (decl);
2290 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2291 && !SYMBOL_REF_USED (XEXP (rtl, 0))
2292 && !incorporeal_function_p (decl))
2294 /* Some systems do require some output. */
2295 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2296 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2299 #endif
2301 void
2302 process_pending_assemble_externals (void)
2304 #ifdef ASM_OUTPUT_EXTERNAL
2305 tree list;
2306 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2307 assemble_external_real (TREE_VALUE (list));
2309 pending_assemble_externals = 0;
2310 pending_assemble_externals_processed = true;
2311 delete pending_assemble_externals_set;
2312 #endif
2315 /* This TREE_LIST contains any weak symbol declarations waiting
2316 to be emitted. */
2317 static GTY(()) tree weak_decls;
2319 /* Output something to declare an external symbol to the assembler,
2320 and qualifiers such as weakness. (Most assemblers don't need
2321 extern declaration, so we normally output nothing.) Do nothing if
2322 DECL is not external. */
2324 void
2325 assemble_external (tree decl ATTRIBUTE_UNUSED)
2327 /* Make sure that the ASM_OUT_FILE is open.
2328 If it's not, we should not be calling this function. */
2329 gcc_assert (asm_out_file);
2331 /* In a perfect world, the following condition would be true.
2332 Sadly, the Java and Go front ends emit assembly *from the front end*,
2333 bypassing the call graph. See PR52739. Fix before GCC 4.8. */
2334 #if 0
2335 /* This function should only be called if we are expanding, or have
2336 expanded, to RTL.
2337 Ideally, only final.c would be calling this function, but it is
2338 not clear whether that would break things somehow. See PR 17982
2339 for further discussion. */
2340 gcc_assert (state == EXPANSION
2341 || state == FINISHED);
2342 #endif
2344 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2345 return;
2347 /* We want to output annotation for weak and external symbols at
2348 very last to check if they are references or not. */
2350 if (TARGET_SUPPORTS_WEAK
2351 && DECL_WEAK (decl)
2352 /* TREE_STATIC is a weird and abused creature which is not
2353 generally the right test for whether an entity has been
2354 locally emitted, inlined or otherwise not-really-extern, but
2355 for declarations that can be weak, it happens to be
2356 match. */
2357 && !TREE_STATIC (decl)
2358 && lookup_attribute ("weak", DECL_ATTRIBUTES (decl))
2359 && value_member (decl, weak_decls) == NULL_TREE)
2360 weak_decls = tree_cons (NULL, decl, weak_decls);
2362 #ifdef ASM_OUTPUT_EXTERNAL
2363 if (pending_assemble_externals_processed)
2365 assemble_external_real (decl);
2366 return;
2369 if (! pending_assemble_externals_set->add (decl))
2370 pending_assemble_externals = tree_cons (NULL, decl,
2371 pending_assemble_externals);
2372 #endif
2375 /* Similar, for calling a library function FUN. */
2377 void
2378 assemble_external_libcall (rtx fun)
2380 /* Declare library function name external when first used, if nec. */
2381 if (! SYMBOL_REF_USED (fun))
2383 SYMBOL_REF_USED (fun) = 1;
2384 targetm.asm_out.external_libcall (fun);
2388 /* Assemble a label named NAME. */
2390 void
2391 assemble_label (FILE *file, const char *name)
2393 ASM_OUTPUT_LABEL (file, name);
2396 /* Set the symbol_referenced flag for ID. */
2397 void
2398 mark_referenced (tree id)
2400 TREE_SYMBOL_REFERENCED (id) = 1;
2403 /* Set the symbol_referenced flag for DECL and notify callgraph. */
2404 void
2405 mark_decl_referenced (tree decl)
2407 if (TREE_CODE (decl) == FUNCTION_DECL)
2409 /* Extern inline functions don't become needed when referenced.
2410 If we know a method will be emitted in other TU and no new
2411 functions can be marked reachable, just use the external
2412 definition. */
2413 struct cgraph_node *node = cgraph_node::get_create (decl);
2414 if (!DECL_EXTERNAL (decl)
2415 && !node->definition)
2416 node->mark_force_output ();
2418 else if (TREE_CODE (decl) == VAR_DECL)
2420 varpool_node *node = varpool_node::get_create (decl);
2421 /* C++ frontend use mark_decl_references to force COMDAT variables
2422 to be output that might appear dead otherwise. */
2423 node->force_output = true;
2425 /* else do nothing - we can get various sorts of CST nodes here,
2426 which do not need to be marked. */
2430 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS
2431 until we find an identifier that is not itself a transparent alias.
2432 Modify the alias passed to it by reference (and all aliases on the
2433 way to the ultimate target), such that they do not have to be
2434 followed again, and return the ultimate target of the alias
2435 chain. */
2437 static inline tree
2438 ultimate_transparent_alias_target (tree *alias)
2440 tree target = *alias;
2442 if (IDENTIFIER_TRANSPARENT_ALIAS (target))
2444 gcc_assert (TREE_CHAIN (target));
2445 target = ultimate_transparent_alias_target (&TREE_CHAIN (target));
2446 gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target)
2447 && ! TREE_CHAIN (target));
2448 *alias = target;
2451 return target;
2454 /* Output to FILE (an assembly file) a reference to NAME. If NAME
2455 starts with a *, the rest of NAME is output verbatim. Otherwise
2456 NAME is transformed in a target-specific way (usually by the
2457 addition of an underscore). */
2459 void
2460 assemble_name_raw (FILE *file, const char *name)
2462 if (name[0] == '*')
2463 fputs (&name[1], file);
2464 else
2465 ASM_OUTPUT_LABELREF (file, name);
2468 /* Like assemble_name_raw, but should be used when NAME might refer to
2469 an entity that is also represented as a tree (like a function or
2470 variable). If NAME does refer to such an entity, that entity will
2471 be marked as referenced. */
2473 void
2474 assemble_name (FILE *file, const char *name)
2476 const char *real_name;
2477 tree id;
2479 real_name = targetm.strip_name_encoding (name);
2481 id = maybe_get_identifier (real_name);
2482 if (id)
2484 tree id_orig = id;
2486 mark_referenced (id);
2487 ultimate_transparent_alias_target (&id);
2488 if (id != id_orig)
2489 name = IDENTIFIER_POINTER (id);
2490 gcc_assert (! TREE_CHAIN (id));
2493 assemble_name_raw (file, name);
2496 /* Allocate SIZE bytes writable static space with a gensym name
2497 and return an RTX to refer to its address. */
2500 assemble_static_space (unsigned HOST_WIDE_INT size)
2502 char name[12];
2503 const char *namestring;
2504 rtx x;
2506 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2507 ++const_labelno;
2508 namestring = ggc_strdup (name);
2510 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2511 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2513 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2514 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2515 BIGGEST_ALIGNMENT);
2516 #else
2517 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2518 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2519 #else
2521 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2522 so that each uninitialized object starts on such a boundary. */
2523 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2524 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2525 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2526 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2527 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2528 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2530 #endif
2531 #endif
2532 return x;
2535 /* Assemble the static constant template for function entry trampolines.
2536 This is done at most once per compilation.
2537 Returns an RTX for the address of the template. */
2539 static GTY(()) rtx initial_trampoline;
2542 assemble_trampoline_template (void)
2544 char label[256];
2545 const char *name;
2546 int align;
2547 rtx symbol;
2549 gcc_assert (targetm.asm_out.trampoline_template != NULL);
2551 if (initial_trampoline)
2552 return initial_trampoline;
2554 /* By default, put trampoline templates in read-only data section. */
2556 #ifdef TRAMPOLINE_SECTION
2557 switch_to_section (TRAMPOLINE_SECTION);
2558 #else
2559 switch_to_section (readonly_data_section);
2560 #endif
2562 /* Write the assembler code to define one. */
2563 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2564 if (align > 0)
2565 ASM_OUTPUT_ALIGN (asm_out_file, align);
2567 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2568 targetm.asm_out.trampoline_template (asm_out_file);
2570 /* Record the rtl to refer to it. */
2571 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2572 name = ggc_strdup (label);
2573 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2574 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2576 initial_trampoline = gen_const_mem (BLKmode, symbol);
2577 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2578 set_mem_size (initial_trampoline, TRAMPOLINE_SIZE);
2580 return initial_trampoline;
2583 /* A and B are either alignments or offsets. Return the minimum alignment
2584 that may be assumed after adding the two together. */
2586 static inline unsigned
2587 min_align (unsigned int a, unsigned int b)
2589 return (a | b) & -(a | b);
2592 /* Return the assembler directive for creating a given kind of integer
2593 object. SIZE is the number of bytes in the object and ALIGNED_P
2594 indicates whether it is known to be aligned. Return NULL if the
2595 assembly dialect has no such directive.
2597 The returned string should be printed at the start of a new line and
2598 be followed immediately by the object's initial value. */
2600 const char *
2601 integer_asm_op (int size, int aligned_p)
2603 struct asm_int_op *ops;
2605 if (aligned_p)
2606 ops = &targetm.asm_out.aligned_op;
2607 else
2608 ops = &targetm.asm_out.unaligned_op;
2610 switch (size)
2612 case 1:
2613 return targetm.asm_out.byte_op;
2614 case 2:
2615 return ops->hi;
2616 case 4:
2617 return ops->si;
2618 case 8:
2619 return ops->di;
2620 case 16:
2621 return ops->ti;
2622 default:
2623 return NULL;
2627 /* Use directive OP to assemble an integer object X. Print OP at the
2628 start of the line, followed immediately by the value of X. */
2630 void
2631 assemble_integer_with_op (const char *op, rtx x)
2633 fputs (op, asm_out_file);
2634 output_addr_const (asm_out_file, x);
2635 fputc ('\n', asm_out_file);
2638 /* The default implementation of the asm_out.integer target hook. */
2640 bool
2641 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2642 unsigned int size ATTRIBUTE_UNUSED,
2643 int aligned_p ATTRIBUTE_UNUSED)
2645 const char *op = integer_asm_op (size, aligned_p);
2646 /* Avoid GAS bugs for large values. Specifically negative values whose
2647 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2648 if (size > UNITS_PER_WORD && size > POINTER_SIZE_UNITS)
2649 return false;
2650 return op && (assemble_integer_with_op (op, x), true);
2653 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2654 the alignment of the integer in bits. Return 1 if we were able to output
2655 the constant, otherwise 0. We must be able to output the constant,
2656 if FORCE is nonzero. */
2658 bool
2659 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2661 int aligned_p;
2663 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2665 /* See if the target hook can handle this kind of object. */
2666 if (targetm.asm_out.integer (x, size, aligned_p))
2667 return true;
2669 /* If the object is a multi-byte one, try splitting it up. Split
2670 it into words it if is multi-word, otherwise split it into bytes. */
2671 if (size > 1)
2673 enum machine_mode omode, imode;
2674 unsigned int subalign;
2675 unsigned int subsize, i;
2676 enum mode_class mclass;
2678 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2679 subalign = MIN (align, subsize * BITS_PER_UNIT);
2680 if (GET_CODE (x) == CONST_FIXED)
2681 mclass = GET_MODE_CLASS (GET_MODE (x));
2682 else
2683 mclass = MODE_INT;
2685 omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0);
2686 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0);
2688 for (i = 0; i < size; i += subsize)
2690 rtx partial = simplify_subreg (omode, x, imode, i);
2691 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2692 break;
2694 if (i == size)
2695 return true;
2697 /* If we've printed some of it, but not all of it, there's no going
2698 back now. */
2699 gcc_assert (!i);
2702 gcc_assert (!force);
2704 return false;
2707 void
2708 assemble_real (REAL_VALUE_TYPE d, enum machine_mode mode, unsigned int align)
2710 long data[4] = {0, 0, 0, 0};
2711 int i;
2712 int bitsize, nelts, nunits, units_per;
2714 /* This is hairy. We have a quantity of known size. real_to_target
2715 will put it into an array of *host* longs, 32 bits per element
2716 (even if long is more than 32 bits). We need to determine the
2717 number of array elements that are occupied (nelts) and the number
2718 of *target* min-addressable units that will be occupied in the
2719 object file (nunits). We cannot assume that 32 divides the
2720 mode's bitsize (size * BITS_PER_UNIT) evenly.
2722 size * BITS_PER_UNIT is used here to make sure that padding bits
2723 (which might appear at either end of the value; real_to_target
2724 will include the padding bits in its output array) are included. */
2726 nunits = GET_MODE_SIZE (mode);
2727 bitsize = nunits * BITS_PER_UNIT;
2728 nelts = CEIL (bitsize, 32);
2729 units_per = 32 / BITS_PER_UNIT;
2731 real_to_target (data, &d, mode);
2733 /* Put out the first word with the specified alignment. */
2734 assemble_integer (GEN_INT (data[0]), MIN (nunits, units_per), align, 1);
2735 nunits -= units_per;
2737 /* Subsequent words need only 32-bit alignment. */
2738 align = min_align (align, 32);
2740 for (i = 1; i < nelts; i++)
2742 assemble_integer (GEN_INT (data[i]), MIN (nunits, units_per), align, 1);
2743 nunits -= units_per;
2747 /* Given an expression EXP with a constant value,
2748 reduce it to the sum of an assembler symbol and an integer.
2749 Store them both in the structure *VALUE.
2750 EXP must be reducible. */
2752 struct addr_const {
2753 rtx base;
2754 HOST_WIDE_INT offset;
2757 static void
2758 decode_addr_const (tree exp, struct addr_const *value)
2760 tree target = TREE_OPERAND (exp, 0);
2761 int offset = 0;
2762 rtx x;
2764 while (1)
2766 if (TREE_CODE (target) == COMPONENT_REF
2767 && tree_fits_shwi_p (byte_position (TREE_OPERAND (target, 1))))
2769 offset += int_byte_position (TREE_OPERAND (target, 1));
2770 target = TREE_OPERAND (target, 0);
2772 else if (TREE_CODE (target) == ARRAY_REF
2773 || TREE_CODE (target) == ARRAY_RANGE_REF)
2775 offset += (tree_to_uhwi (TYPE_SIZE_UNIT (TREE_TYPE (target)))
2776 * tree_to_shwi (TREE_OPERAND (target, 1)));
2777 target = TREE_OPERAND (target, 0);
2779 else if (TREE_CODE (target) == MEM_REF
2780 && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR)
2782 offset += mem_ref_offset (target).to_short_addr ();
2783 target = TREE_OPERAND (TREE_OPERAND (target, 0), 0);
2785 else if (TREE_CODE (target) == INDIRECT_REF
2786 && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR
2787 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0))
2788 == ADDR_EXPR)
2789 target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0);
2790 else
2791 break;
2794 switch (TREE_CODE (target))
2796 case VAR_DECL:
2797 case FUNCTION_DECL:
2798 x = DECL_RTL (target);
2799 break;
2801 case LABEL_DECL:
2802 x = gen_rtx_MEM (FUNCTION_MODE,
2803 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2804 break;
2806 case REAL_CST:
2807 case FIXED_CST:
2808 case STRING_CST:
2809 case COMPLEX_CST:
2810 case CONSTRUCTOR:
2811 case INTEGER_CST:
2812 x = output_constant_def (target, 1);
2813 break;
2815 default:
2816 gcc_unreachable ();
2819 gcc_assert (MEM_P (x));
2820 x = XEXP (x, 0);
2822 value->base = x;
2823 value->offset = offset;
2827 static GTY((param_is (struct constant_descriptor_tree)))
2828 htab_t const_desc_htab;
2830 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2832 /* Constant pool accessor function. */
2834 htab_t
2835 constant_pool_htab (void)
2837 return const_desc_htab;
2840 /* Compute a hash code for a constant expression. */
2842 static hashval_t
2843 const_desc_hash (const void *ptr)
2845 return ((const struct constant_descriptor_tree *)ptr)->hash;
2848 static hashval_t
2849 const_hash_1 (const tree exp)
2851 const char *p;
2852 hashval_t hi;
2853 int len, i;
2854 enum tree_code code = TREE_CODE (exp);
2856 /* Either set P and LEN to the address and len of something to hash and
2857 exit the switch or return a value. */
2859 switch (code)
2861 case INTEGER_CST:
2862 p = (char *) &TREE_INT_CST_ELT (exp, 0);
2863 len = TREE_INT_CST_NUNITS (exp) * sizeof (HOST_WIDE_INT);
2864 break;
2866 case REAL_CST:
2867 return real_hash (TREE_REAL_CST_PTR (exp));
2869 case FIXED_CST:
2870 return fixed_hash (TREE_FIXED_CST_PTR (exp));
2872 case STRING_CST:
2873 p = TREE_STRING_POINTER (exp);
2874 len = TREE_STRING_LENGTH (exp);
2875 break;
2877 case COMPLEX_CST:
2878 return (const_hash_1 (TREE_REALPART (exp)) * 5
2879 + const_hash_1 (TREE_IMAGPART (exp)));
2881 case VECTOR_CST:
2883 unsigned i;
2885 hi = 7 + VECTOR_CST_NELTS (exp);
2887 for (i = 0; i < VECTOR_CST_NELTS (exp); ++i)
2888 hi = hi * 563 + const_hash_1 (VECTOR_CST_ELT (exp, i));
2890 return hi;
2893 case CONSTRUCTOR:
2895 unsigned HOST_WIDE_INT idx;
2896 tree value;
2898 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2900 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
2901 if (value)
2902 hi = hi * 603 + const_hash_1 (value);
2904 return hi;
2907 case ADDR_EXPR:
2908 case FDESC_EXPR:
2910 struct addr_const value;
2912 decode_addr_const (exp, &value);
2913 switch (GET_CODE (value.base))
2915 case SYMBOL_REF:
2916 /* Don't hash the address of the SYMBOL_REF;
2917 only use the offset and the symbol name. */
2918 hi = value.offset;
2919 p = XSTR (value.base, 0);
2920 for (i = 0; p[i] != 0; i++)
2921 hi = ((hi * 613) + (unsigned) (p[i]));
2922 break;
2924 case LABEL_REF:
2925 hi = (value.offset
2926 + CODE_LABEL_NUMBER (LABEL_REF_LABEL (value.base)) * 13);
2927 break;
2929 default:
2930 gcc_unreachable ();
2933 return hi;
2935 case PLUS_EXPR:
2936 case POINTER_PLUS_EXPR:
2937 case MINUS_EXPR:
2938 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2939 + const_hash_1 (TREE_OPERAND (exp, 1)));
2941 CASE_CONVERT:
2942 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
2944 default:
2945 /* A language specific constant. Just hash the code. */
2946 return code;
2949 /* Compute hashing function. */
2950 hi = len;
2951 for (i = 0; i < len; i++)
2952 hi = ((hi * 613) + (unsigned) (p[i]));
2954 return hi;
2957 /* Wrapper of compare_constant, for the htab interface. */
2958 static int
2959 const_desc_eq (const void *p1, const void *p2)
2961 const struct constant_descriptor_tree *const c1
2962 = (const struct constant_descriptor_tree *) p1;
2963 const struct constant_descriptor_tree *const c2
2964 = (const struct constant_descriptor_tree *) p2;
2965 if (c1->hash != c2->hash)
2966 return 0;
2967 return compare_constant (c1->value, c2->value);
2970 /* Compare t1 and t2, and return 1 only if they are known to result in
2971 the same bit pattern on output. */
2973 static int
2974 compare_constant (const tree t1, const tree t2)
2976 enum tree_code typecode;
2978 if (t1 == NULL_TREE)
2979 return t2 == NULL_TREE;
2980 if (t2 == NULL_TREE)
2981 return 0;
2983 if (TREE_CODE (t1) != TREE_CODE (t2))
2984 return 0;
2986 switch (TREE_CODE (t1))
2988 case INTEGER_CST:
2989 /* Integer constants are the same only if the same width of type. */
2990 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2991 return 0;
2992 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2993 return 0;
2994 return tree_int_cst_equal (t1, t2);
2996 case REAL_CST:
2997 /* Real constants are the same only if the same width of type. */
2998 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2999 return 0;
3001 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
3003 case FIXED_CST:
3004 /* Fixed constants are the same only if the same width of type. */
3005 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3006 return 0;
3008 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
3010 case STRING_CST:
3011 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3012 return 0;
3014 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
3015 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
3016 TREE_STRING_LENGTH (t1)));
3018 case COMPLEX_CST:
3019 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
3020 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
3022 case VECTOR_CST:
3024 unsigned i;
3026 if (VECTOR_CST_NELTS (t1) != VECTOR_CST_NELTS (t2))
3027 return 0;
3029 for (i = 0; i < VECTOR_CST_NELTS (t1); ++i)
3030 if (!compare_constant (VECTOR_CST_ELT (t1, i),
3031 VECTOR_CST_ELT (t2, i)))
3032 return 0;
3034 return 1;
3037 case CONSTRUCTOR:
3039 vec<constructor_elt, va_gc> *v1, *v2;
3040 unsigned HOST_WIDE_INT idx;
3042 typecode = TREE_CODE (TREE_TYPE (t1));
3043 if (typecode != TREE_CODE (TREE_TYPE (t2)))
3044 return 0;
3046 if (typecode == ARRAY_TYPE)
3048 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
3049 /* For arrays, check that the sizes all match. */
3050 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
3051 || size_1 == -1
3052 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
3053 return 0;
3055 else
3057 /* For record and union constructors, require exact type
3058 equality. */
3059 if (TREE_TYPE (t1) != TREE_TYPE (t2))
3060 return 0;
3063 v1 = CONSTRUCTOR_ELTS (t1);
3064 v2 = CONSTRUCTOR_ELTS (t2);
3065 if (vec_safe_length (v1) != vec_safe_length (v2))
3066 return 0;
3068 for (idx = 0; idx < vec_safe_length (v1); ++idx)
3070 constructor_elt *c1 = &(*v1)[idx];
3071 constructor_elt *c2 = &(*v2)[idx];
3073 /* Check that each value is the same... */
3074 if (!compare_constant (c1->value, c2->value))
3075 return 0;
3076 /* ... and that they apply to the same fields! */
3077 if (typecode == ARRAY_TYPE)
3079 if (!compare_constant (c1->index, c2->index))
3080 return 0;
3082 else
3084 if (c1->index != c2->index)
3085 return 0;
3089 return 1;
3092 case ADDR_EXPR:
3093 case FDESC_EXPR:
3095 struct addr_const value1, value2;
3096 enum rtx_code code;
3097 int ret;
3099 decode_addr_const (t1, &value1);
3100 decode_addr_const (t2, &value2);
3102 if (value1.offset != value2.offset)
3103 return 0;
3105 code = GET_CODE (value1.base);
3106 if (code != GET_CODE (value2.base))
3107 return 0;
3109 switch (code)
3111 case SYMBOL_REF:
3112 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3113 break;
3115 case LABEL_REF:
3116 ret = (CODE_LABEL_NUMBER (LABEL_REF_LABEL (value1.base))
3117 == CODE_LABEL_NUMBER (LABEL_REF_LABEL (value2.base)));
3118 break;
3120 default:
3121 gcc_unreachable ();
3123 return ret;
3126 case PLUS_EXPR:
3127 case POINTER_PLUS_EXPR:
3128 case MINUS_EXPR:
3129 case RANGE_EXPR:
3130 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3131 && compare_constant (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3133 CASE_CONVERT:
3134 case VIEW_CONVERT_EXPR:
3135 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3137 default:
3138 return 0;
3141 gcc_unreachable ();
3144 /* Return the section into which constant EXP should be placed. */
3146 static section *
3147 get_constant_section (tree exp, unsigned int align)
3149 return targetm.asm_out.select_section (exp,
3150 compute_reloc_for_constant (exp),
3151 align);
3154 /* Return the size of constant EXP in bytes. */
3156 static HOST_WIDE_INT
3157 get_constant_size (tree exp)
3159 HOST_WIDE_INT size;
3161 size = int_size_in_bytes (TREE_TYPE (exp));
3162 if (TREE_CODE (exp) == STRING_CST)
3163 size = MAX (TREE_STRING_LENGTH (exp), size);
3164 return size;
3167 /* Subroutine of output_constant_def:
3168 No constant equal to EXP is known to have been output.
3169 Make a constant descriptor to enter EXP in the hash table.
3170 Assign the label number and construct RTL to refer to the
3171 constant's location in memory.
3172 Caller is responsible for updating the hash table. */
3174 static struct constant_descriptor_tree *
3175 build_constant_desc (tree exp)
3177 struct constant_descriptor_tree *desc;
3178 rtx symbol, rtl;
3179 char label[256];
3180 int labelno;
3181 tree decl;
3183 desc = ggc_alloc<constant_descriptor_tree> ();
3184 desc->value = exp;
3186 /* Create a string containing the label name, in LABEL. */
3187 labelno = const_labelno++;
3188 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3190 /* Construct the VAR_DECL associated with the constant. */
3191 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3192 TREE_TYPE (exp));
3193 DECL_ARTIFICIAL (decl) = 1;
3194 DECL_IGNORED_P (decl) = 1;
3195 TREE_READONLY (decl) = 1;
3196 TREE_STATIC (decl) = 1;
3197 TREE_ADDRESSABLE (decl) = 1;
3198 /* We don't set the RTL yet as this would cause varpool to assume that the
3199 variable is referenced. Moreover, it would just be dropped in LTO mode.
3200 Instead we set the flag that will be recognized in make_decl_rtl. */
3201 DECL_IN_CONSTANT_POOL (decl) = 1;
3202 DECL_INITIAL (decl) = desc->value;
3203 /* ??? CONSTANT_ALIGNMENT hasn't been updated for vector types on most
3204 architectures so use DATA_ALIGNMENT as well, except for strings. */
3205 if (TREE_CODE (exp) == STRING_CST)
3207 #ifdef CONSTANT_ALIGNMENT
3208 DECL_ALIGN (decl) = CONSTANT_ALIGNMENT (exp, DECL_ALIGN (decl));
3209 #endif
3211 else
3212 align_variable (decl, 0);
3214 /* Now construct the SYMBOL_REF and the MEM. */
3215 if (use_object_blocks_p ())
3217 section *sect = get_constant_section (exp, DECL_ALIGN (decl));
3218 symbol = create_block_symbol (ggc_strdup (label),
3219 get_block_for_section (sect), -1);
3221 else
3222 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3223 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3224 SET_SYMBOL_REF_DECL (symbol, decl);
3225 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3227 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3228 set_mem_attributes (rtl, exp, 1);
3229 set_mem_alias_set (rtl, 0);
3230 set_mem_alias_set (rtl, const_alias_set);
3232 /* We cannot share RTX'es in pool entries.
3233 Mark this piece of RTL as required for unsharing. */
3234 RTX_FLAG (rtl, used) = 1;
3236 /* Set flags or add text to the name to record information, such as
3237 that it is a local symbol. If the name is changed, the macro
3238 ASM_OUTPUT_LABELREF will have to know how to strip this
3239 information. This call might invalidate our local variable
3240 SYMBOL; we can't use it afterward. */
3241 targetm.encode_section_info (exp, rtl, true);
3243 desc->rtl = rtl;
3245 return desc;
3248 /* Return an rtx representing a reference to constant data in memory
3249 for the constant expression EXP.
3251 If assembler code for such a constant has already been output,
3252 return an rtx to refer to it.
3253 Otherwise, output such a constant in memory
3254 and generate an rtx for it.
3256 If DEFER is nonzero, this constant can be deferred and output only
3257 if referenced in the function after all optimizations.
3259 `const_desc_table' records which constants already have label strings. */
3262 output_constant_def (tree exp, int defer)
3264 struct constant_descriptor_tree *desc;
3265 struct constant_descriptor_tree key;
3266 void **loc;
3268 /* Look up EXP in the table of constant descriptors. If we didn't find
3269 it, create a new one. */
3270 key.value = exp;
3271 key.hash = const_hash_1 (exp);
3272 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3274 desc = (struct constant_descriptor_tree *) *loc;
3275 if (desc == 0)
3277 desc = build_constant_desc (exp);
3278 desc->hash = key.hash;
3279 *loc = desc;
3282 maybe_output_constant_def_contents (desc, defer);
3283 return desc->rtl;
3286 /* Subroutine of output_constant_def: Decide whether or not we need to
3287 output the constant DESC now, and if so, do it. */
3288 static void
3289 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3290 int defer)
3292 rtx symbol = XEXP (desc->rtl, 0);
3293 tree exp = desc->value;
3295 if (flag_syntax_only)
3296 return;
3298 if (TREE_ASM_WRITTEN (exp))
3299 /* Already output; don't do it again. */
3300 return;
3302 /* We can always defer constants as long as the context allows
3303 doing so. */
3304 if (defer)
3306 /* Increment n_deferred_constants if it exists. It needs to be at
3307 least as large as the number of constants actually referred to
3308 by the function. If it's too small we'll stop looking too early
3309 and fail to emit constants; if it's too large we'll only look
3310 through the entire function when we could have stopped earlier. */
3311 if (cfun)
3312 n_deferred_constants++;
3313 return;
3316 output_constant_def_contents (symbol);
3319 /* Subroutine of output_constant_def_contents. Output the definition
3320 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3321 constant's alignment in bits. */
3323 static void
3324 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3326 HOST_WIDE_INT size;
3328 size = get_constant_size (exp);
3330 /* Do any machine/system dependent processing of the constant. */
3331 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3333 /* Output the value of EXP. */
3334 output_constant (exp, size, align);
3337 /* We must output the constant data referred to by SYMBOL; do so. */
3339 static void
3340 output_constant_def_contents (rtx symbol)
3342 tree decl = SYMBOL_REF_DECL (symbol);
3343 tree exp = DECL_INITIAL (decl);
3344 unsigned int align;
3345 bool asan_protected = false;
3347 /* Make sure any other constants whose addresses appear in EXP
3348 are assigned label numbers. */
3349 output_addressed_constants (exp);
3351 /* We are no longer deferring this constant. */
3352 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3354 if ((flag_sanitize & SANITIZE_ADDRESS)
3355 && TREE_CODE (exp) == STRING_CST
3356 && asan_protect_global (exp))
3358 asan_protected = true;
3359 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
3360 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
3363 /* If the constant is part of an object block, make sure that the
3364 decl has been positioned within its block, but do not write out
3365 its definition yet. output_object_blocks will do that later. */
3366 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3367 place_block_symbol (symbol);
3368 else
3370 align = DECL_ALIGN (decl);
3371 switch_to_section (get_constant_section (exp, align));
3372 if (align > BITS_PER_UNIT)
3373 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3374 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3375 if (asan_protected)
3377 HOST_WIDE_INT size = get_constant_size (exp);
3378 assemble_zeros (asan_red_zone_size (size));
3383 /* Look up EXP in the table of constant descriptors. Return the rtl
3384 if it has been emitted, else null. */
3387 lookup_constant_def (tree exp)
3389 struct constant_descriptor_tree *desc;
3390 struct constant_descriptor_tree key;
3392 key.value = exp;
3393 key.hash = const_hash_1 (exp);
3394 desc = (struct constant_descriptor_tree *)
3395 htab_find_with_hash (const_desc_htab, &key, key.hash);
3397 return (desc ? desc->rtl : NULL_RTX);
3400 /* Return a tree representing a reference to constant data in memory
3401 for the constant expression EXP.
3403 This is the counterpart of output_constant_def at the Tree level. */
3405 tree
3406 tree_output_constant_def (tree exp)
3408 struct constant_descriptor_tree *desc, key;
3409 void **loc;
3410 tree decl;
3412 /* Look up EXP in the table of constant descriptors. If we didn't find
3413 it, create a new one. */
3414 key.value = exp;
3415 key.hash = const_hash_1 (exp);
3416 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3418 desc = (struct constant_descriptor_tree *) *loc;
3419 if (desc == 0)
3421 desc = build_constant_desc (exp);
3422 desc->hash = key.hash;
3423 *loc = desc;
3426 decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3427 varpool_node::finalize_decl (decl);
3428 return decl;
3431 /* Used in the hash tables to avoid outputting the same constant
3432 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3433 are output once per function, not once per file. */
3434 /* ??? Only a few targets need per-function constant pools. Most
3435 can use one per-file pool. Should add a targetm bit to tell the
3436 difference. */
3438 struct GTY(()) rtx_constant_pool {
3439 /* Pointers to first and last constant in pool, as ordered by offset. */
3440 struct constant_descriptor_rtx *first;
3441 struct constant_descriptor_rtx *last;
3443 /* Hash facility for making memory-constants from constant rtl-expressions.
3444 It is used on RISC machines where immediate integer arguments and
3445 constant addresses are restricted so that such constants must be stored
3446 in memory. */
3447 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_htab;
3449 /* Current offset in constant pool (does not include any
3450 machine-specific header). */
3451 HOST_WIDE_INT offset;
3454 struct GTY((chain_next ("%h.next"))) constant_descriptor_rtx {
3455 struct constant_descriptor_rtx *next;
3456 rtx mem;
3457 rtx sym;
3458 rtx constant;
3459 HOST_WIDE_INT offset;
3460 hashval_t hash;
3461 enum machine_mode mode;
3462 unsigned int align;
3463 int labelno;
3464 int mark;
3467 /* Hash and compare functions for const_rtx_htab. */
3469 static hashval_t
3470 const_desc_rtx_hash (const void *ptr)
3472 const struct constant_descriptor_rtx *const desc
3473 = (const struct constant_descriptor_rtx *) ptr;
3474 return desc->hash;
3477 static int
3478 const_desc_rtx_eq (const void *a, const void *b)
3480 const struct constant_descriptor_rtx *const x
3481 = (const struct constant_descriptor_rtx *) a;
3482 const struct constant_descriptor_rtx *const y
3483 = (const struct constant_descriptor_rtx *) b;
3485 if (x->mode != y->mode)
3486 return 0;
3487 return rtx_equal_p (x->constant, y->constant);
3490 /* Hash one component of a constant. */
3492 static hashval_t
3493 const_rtx_hash_1 (const_rtx x)
3495 unsigned HOST_WIDE_INT hwi;
3496 enum machine_mode mode;
3497 enum rtx_code code;
3498 hashval_t h;
3499 int i;
3501 code = GET_CODE (x);
3502 mode = GET_MODE (x);
3503 h = (hashval_t) code * 1048573 + mode;
3505 switch (code)
3507 case CONST_INT:
3508 hwi = INTVAL (x);
3510 fold_hwi:
3512 int shift = sizeof (hashval_t) * CHAR_BIT;
3513 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3515 h ^= (hashval_t) hwi;
3516 for (i = 1; i < n; ++i)
3518 hwi >>= shift;
3519 h ^= (hashval_t) hwi;
3522 break;
3524 case CONST_WIDE_INT:
3525 hwi = GET_MODE_PRECISION (mode);
3527 for (i = 0; i < CONST_WIDE_INT_NUNITS (x); i++)
3528 hwi ^= CONST_WIDE_INT_ELT (x, i);
3529 goto fold_hwi;
3532 case CONST_DOUBLE:
3533 if (TARGET_SUPPORTS_WIDE_INT == 0 && mode == VOIDmode)
3535 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3536 goto fold_hwi;
3538 else
3539 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3540 break;
3542 case CONST_FIXED:
3543 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3544 break;
3546 case SYMBOL_REF:
3547 h ^= htab_hash_string (XSTR (x, 0));
3548 break;
3550 case LABEL_REF:
3551 h = h * 251 + CODE_LABEL_NUMBER (LABEL_REF_LABEL (x));
3552 break;
3554 case UNSPEC:
3555 case UNSPEC_VOLATILE:
3556 h = h * 251 + XINT (x, 1);
3557 break;
3559 default:
3560 break;
3563 return h;
3566 /* Compute a hash value for X, which should be a constant. */
3568 static hashval_t
3569 const_rtx_hash (rtx x)
3571 hashval_t h = 0;
3572 subrtx_iterator::array_type array;
3573 FOR_EACH_SUBRTX (iter, array, x, ALL)
3574 h = h * 509 + const_rtx_hash_1 (*iter);
3575 return h;
3579 /* Create and return a new rtx constant pool. */
3581 static struct rtx_constant_pool *
3582 create_constant_pool (void)
3584 struct rtx_constant_pool *pool;
3586 pool = ggc_alloc<rtx_constant_pool> ();
3587 pool->const_rtx_htab = htab_create_ggc (31, const_desc_rtx_hash,
3588 const_desc_rtx_eq, NULL);
3589 pool->first = NULL;
3590 pool->last = NULL;
3591 pool->offset = 0;
3592 return pool;
3595 /* Initialize constant pool hashing for a new function. */
3597 void
3598 init_varasm_status (void)
3600 crtl->varasm.pool = create_constant_pool ();
3601 crtl->varasm.deferred_constants = 0;
3604 /* Given a MINUS expression, simplify it if both sides
3605 include the same symbol. */
3608 simplify_subtraction (rtx x)
3610 rtx r = simplify_rtx (x);
3611 return r ? r : x;
3614 /* Given a constant rtx X, make (or find) a memory constant for its value
3615 and return a MEM rtx to refer to it in memory. */
3618 force_const_mem (enum machine_mode mode, rtx x)
3620 struct constant_descriptor_rtx *desc, tmp;
3621 struct rtx_constant_pool *pool;
3622 char label[256];
3623 rtx def, symbol;
3624 hashval_t hash;
3625 unsigned int align;
3626 void **slot;
3628 /* If we're not allowed to drop X into the constant pool, don't. */
3629 if (targetm.cannot_force_const_mem (mode, x))
3630 return NULL_RTX;
3632 /* Record that this function has used a constant pool entry. */
3633 crtl->uses_const_pool = 1;
3635 /* Decide which pool to use. */
3636 pool = (targetm.use_blocks_for_constant_p (mode, x)
3637 ? shared_constant_pool
3638 : crtl->varasm.pool);
3640 /* Lookup the value in the hashtable. */
3641 tmp.constant = x;
3642 tmp.mode = mode;
3643 hash = const_rtx_hash (x);
3644 slot = htab_find_slot_with_hash (pool->const_rtx_htab, &tmp, hash, INSERT);
3645 desc = (struct constant_descriptor_rtx *) *slot;
3647 /* If the constant was already present, return its memory. */
3648 if (desc)
3649 return copy_rtx (desc->mem);
3651 /* Otherwise, create a new descriptor. */
3652 desc = ggc_alloc<constant_descriptor_rtx> ();
3653 *slot = desc;
3655 /* Align the location counter as required by EXP's data type. */
3656 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3657 #ifdef CONSTANT_ALIGNMENT
3659 tree type = lang_hooks.types.type_for_mode (mode, 0);
3660 if (type != NULL_TREE)
3661 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3663 #endif
3665 pool->offset += (align / BITS_PER_UNIT) - 1;
3666 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3668 desc->next = NULL;
3669 desc->constant = copy_rtx (tmp.constant);
3670 desc->offset = pool->offset;
3671 desc->hash = hash;
3672 desc->mode = mode;
3673 desc->align = align;
3674 desc->labelno = const_labelno;
3675 desc->mark = 0;
3677 pool->offset += GET_MODE_SIZE (mode);
3678 if (pool->last)
3679 pool->last->next = desc;
3680 else
3681 pool->first = pool->last = desc;
3682 pool->last = desc;
3684 /* Create a string containing the label name, in LABEL. */
3685 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3686 ++const_labelno;
3688 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3689 the constants pool. */
3690 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3692 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3693 symbol = create_block_symbol (ggc_strdup (label),
3694 get_block_for_section (sect), -1);
3696 else
3697 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3698 desc->sym = symbol;
3699 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3700 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3701 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3703 /* Construct the MEM. */
3704 desc->mem = def = gen_const_mem (mode, symbol);
3705 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3706 set_mem_align (def, align);
3708 /* If we're dropping a label to the constant pool, make sure we
3709 don't delete it. */
3710 if (GET_CODE (x) == LABEL_REF)
3711 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3713 return copy_rtx (def);
3716 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3719 get_pool_constant (const_rtx addr)
3721 return SYMBOL_REF_CONSTANT (addr)->constant;
3724 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3725 and whether it has been output or not. */
3728 get_pool_constant_mark (rtx addr, bool *pmarked)
3730 struct constant_descriptor_rtx *desc;
3732 desc = SYMBOL_REF_CONSTANT (addr);
3733 *pmarked = (desc->mark != 0);
3734 return desc->constant;
3737 /* Similar, return the mode. */
3739 enum machine_mode
3740 get_pool_mode (const_rtx addr)
3742 return SYMBOL_REF_CONSTANT (addr)->mode;
3745 /* Return the size of the constant pool. */
3748 get_pool_size (void)
3750 return crtl->varasm.pool->offset;
3753 /* Worker function for output_constant_pool_1. Emit assembly for X
3754 in MODE with known alignment ALIGN. */
3756 static void
3757 output_constant_pool_2 (enum machine_mode mode, rtx x, unsigned int align)
3759 switch (GET_MODE_CLASS (mode))
3761 case MODE_FLOAT:
3762 case MODE_DECIMAL_FLOAT:
3764 REAL_VALUE_TYPE r;
3766 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3767 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3768 assemble_real (r, mode, align);
3769 break;
3772 case MODE_INT:
3773 case MODE_PARTIAL_INT:
3774 case MODE_FRACT:
3775 case MODE_UFRACT:
3776 case MODE_ACCUM:
3777 case MODE_UACCUM:
3778 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3779 break;
3781 case MODE_VECTOR_FLOAT:
3782 case MODE_VECTOR_INT:
3783 case MODE_VECTOR_FRACT:
3784 case MODE_VECTOR_UFRACT:
3785 case MODE_VECTOR_ACCUM:
3786 case MODE_VECTOR_UACCUM:
3788 int i, units;
3789 enum machine_mode submode = GET_MODE_INNER (mode);
3790 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3792 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3793 units = CONST_VECTOR_NUNITS (x);
3795 for (i = 0; i < units; i++)
3797 rtx elt = CONST_VECTOR_ELT (x, i);
3798 output_constant_pool_2 (submode, elt, i ? subalign : align);
3801 break;
3803 default:
3804 gcc_unreachable ();
3808 /* Worker function for output_constant_pool. Emit constant DESC,
3809 giving it ALIGN bits of alignment. */
3811 static void
3812 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3813 unsigned int align)
3815 rtx x, tmp;
3817 x = desc->constant;
3819 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3820 whose CODE_LABEL has been deleted. This can occur if a jump table
3821 is eliminated by optimization. If so, write a constant of zero
3822 instead. Note that this can also happen by turning the
3823 CODE_LABEL into a NOTE. */
3824 /* ??? This seems completely and utterly wrong. Certainly it's
3825 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3826 functioning even with rtx_insn::deleted and friends. */
3828 tmp = x;
3829 switch (GET_CODE (tmp))
3831 case CONST:
3832 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3833 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
3834 break;
3835 tmp = XEXP (XEXP (tmp, 0), 0);
3836 /* FALLTHRU */
3838 case LABEL_REF:
3839 tmp = LABEL_REF_LABEL (tmp);
3840 gcc_assert (!as_a<rtx_insn *> (tmp)->deleted ());
3841 gcc_assert (!NOTE_P (tmp)
3842 || NOTE_KIND (tmp) != NOTE_INSN_DELETED);
3843 break;
3845 default:
3846 break;
3849 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3850 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3851 align, desc->labelno, done);
3852 #endif
3854 assemble_align (align);
3856 /* Output the label. */
3857 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3859 /* Output the data. */
3860 output_constant_pool_2 (desc->mode, x, align);
3862 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3863 sections have proper size. */
3864 if (align > GET_MODE_BITSIZE (desc->mode)
3865 && in_section
3866 && (in_section->common.flags & SECTION_MERGE))
3867 assemble_align (align);
3869 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3870 done:
3871 #endif
3872 return;
3875 /* Mark all constants that are referenced by SYMBOL_REFs in X.
3876 Emit referenced deferred strings. */
3878 static void
3879 mark_constants_in_pattern (rtx insn)
3881 subrtx_iterator::array_type array;
3882 FOR_EACH_SUBRTX (iter, array, PATTERN (insn), ALL)
3884 const_rtx x = *iter;
3885 if (GET_CODE (x) == SYMBOL_REF)
3887 if (CONSTANT_POOL_ADDRESS_P (x))
3889 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
3890 if (desc->mark == 0)
3892 desc->mark = 1;
3893 iter.substitute (desc->constant);
3896 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3898 tree decl = SYMBOL_REF_DECL (x);
3899 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
3901 n_deferred_constants--;
3902 output_constant_def_contents (CONST_CAST_RTX (x));
3909 /* Look through appropriate parts of INSN, marking all entries in the
3910 constant pool which are actually being used. Entries that are only
3911 referenced by other constants are also marked as used. Emit
3912 deferred strings that are used. */
3914 static void
3915 mark_constants (rtx_insn *insn)
3917 if (!INSN_P (insn))
3918 return;
3920 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3921 insns, not any notes that may be attached. We don't want to mark
3922 a constant just because it happens to appear in a REG_EQUIV note. */
3923 if (rtx_sequence *seq = dyn_cast <rtx_sequence *> (PATTERN (insn)))
3925 int i, n = seq->len ();
3926 for (i = 0; i < n; ++i)
3928 rtx subinsn = seq->element (i);
3929 if (INSN_P (subinsn))
3930 mark_constants_in_pattern (subinsn);
3933 else
3934 mark_constants_in_pattern (insn);
3937 /* Look through the instructions for this function, and mark all the
3938 entries in POOL which are actually being used. Emit deferred constants
3939 which have indeed been used. */
3941 static void
3942 mark_constant_pool (void)
3944 rtx_insn *insn;
3946 if (!crtl->uses_const_pool && n_deferred_constants == 0)
3947 return;
3949 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3950 mark_constants (insn);
3953 /* Write all the constants in POOL. */
3955 static void
3956 output_constant_pool_contents (struct rtx_constant_pool *pool)
3958 struct constant_descriptor_rtx *desc;
3960 for (desc = pool->first; desc ; desc = desc->next)
3961 if (desc->mark)
3963 /* If the constant is part of an object_block, make sure that
3964 the constant has been positioned within its block, but do not
3965 write out its definition yet. output_object_blocks will do
3966 that later. */
3967 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
3968 && SYMBOL_REF_BLOCK (desc->sym))
3969 place_block_symbol (desc->sym);
3970 else
3972 switch_to_section (targetm.asm_out.select_rtx_section
3973 (desc->mode, desc->constant, desc->align));
3974 output_constant_pool_1 (desc, desc->align);
3979 /* Mark all constants that are used in the current function, then write
3980 out the function's private constant pool. */
3982 static void
3983 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
3984 tree fndecl ATTRIBUTE_UNUSED)
3986 struct rtx_constant_pool *pool = crtl->varasm.pool;
3988 /* It is possible for gcc to call force_const_mem and then to later
3989 discard the instructions which refer to the constant. In such a
3990 case we do not need to output the constant. */
3991 mark_constant_pool ();
3993 #ifdef ASM_OUTPUT_POOL_PROLOGUE
3994 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
3995 #endif
3997 output_constant_pool_contents (pool);
3999 #ifdef ASM_OUTPUT_POOL_EPILOGUE
4000 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
4001 #endif
4004 /* Write the contents of the shared constant pool. */
4006 void
4007 output_shared_constant_pool (void)
4009 output_constant_pool_contents (shared_constant_pool);
4012 /* Determine what kind of relocations EXP may need. */
4015 compute_reloc_for_constant (tree exp)
4017 int reloc = 0, reloc2;
4018 tree tem;
4020 switch (TREE_CODE (exp))
4022 case ADDR_EXPR:
4023 case FDESC_EXPR:
4024 /* Go inside any operations that get_inner_reference can handle and see
4025 if what's inside is a constant: no need to do anything here for
4026 addresses of variables or functions. */
4027 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4028 tem = TREE_OPERAND (tem, 0))
4031 if (TREE_CODE (tem) == MEM_REF
4032 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4034 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4035 break;
4038 if (!targetm.binds_local_p (tem))
4039 reloc |= 2;
4040 else
4041 reloc |= 1;
4042 break;
4044 case PLUS_EXPR:
4045 case POINTER_PLUS_EXPR:
4046 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4047 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4048 break;
4050 case MINUS_EXPR:
4051 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4052 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4053 /* The difference of two local labels is computable at link time. */
4054 if (reloc == 1 && reloc2 == 1)
4055 reloc = 0;
4056 else
4057 reloc |= reloc2;
4058 break;
4060 CASE_CONVERT:
4061 case VIEW_CONVERT_EXPR:
4062 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4063 break;
4065 case CONSTRUCTOR:
4067 unsigned HOST_WIDE_INT idx;
4068 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4069 if (tem != 0)
4070 reloc |= compute_reloc_for_constant (tem);
4072 break;
4074 default:
4075 break;
4077 return reloc;
4080 /* Find all the constants whose addresses are referenced inside of EXP,
4081 and make sure assembler code with a label has been output for each one.
4082 Indicate whether an ADDR_EXPR has been encountered. */
4084 static void
4085 output_addressed_constants (tree exp)
4087 tree tem;
4089 switch (TREE_CODE (exp))
4091 case ADDR_EXPR:
4092 case FDESC_EXPR:
4093 /* Go inside any operations that get_inner_reference can handle and see
4094 if what's inside is a constant: no need to do anything here for
4095 addresses of variables or functions. */
4096 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4097 tem = TREE_OPERAND (tem, 0))
4100 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4101 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4102 tem = DECL_INITIAL (tem);
4104 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4105 output_constant_def (tem, 0);
4107 if (TREE_CODE (tem) == MEM_REF)
4108 output_addressed_constants (TREE_OPERAND (tem, 0));
4109 break;
4111 case PLUS_EXPR:
4112 case POINTER_PLUS_EXPR:
4113 case MINUS_EXPR:
4114 output_addressed_constants (TREE_OPERAND (exp, 1));
4115 /* Fall through. */
4117 CASE_CONVERT:
4118 case VIEW_CONVERT_EXPR:
4119 output_addressed_constants (TREE_OPERAND (exp, 0));
4120 break;
4122 case CONSTRUCTOR:
4124 unsigned HOST_WIDE_INT idx;
4125 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4126 if (tem != 0)
4127 output_addressed_constants (tem);
4129 break;
4131 default:
4132 break;
4136 /* Whether a constructor CTOR is a valid static constant initializer if all
4137 its elements are. This used to be internal to initializer_constant_valid_p
4138 and has been exposed to let other functions like categorize_ctor_elements
4139 evaluate the property while walking a constructor for other purposes. */
4141 bool
4142 constructor_static_from_elts_p (const_tree ctor)
4144 return (TREE_CONSTANT (ctor)
4145 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4146 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4147 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4150 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4151 tree *cache);
4153 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4154 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4155 which are valid when ENDTYPE is an integer of any size; in
4156 particular, this does not accept a pointer minus a constant. This
4157 returns null_pointer_node if the VALUE is an absolute constant
4158 which can be used to initialize a static variable. Otherwise it
4159 returns NULL. */
4161 static tree
4162 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4164 tree op0, op1;
4166 if (!INTEGRAL_TYPE_P (endtype))
4167 return NULL_TREE;
4169 op0 = TREE_OPERAND (value, 0);
4170 op1 = TREE_OPERAND (value, 1);
4172 /* Like STRIP_NOPS except allow the operand mode to widen. This
4173 works around a feature of fold that simplifies (int)(p1 - p2) to
4174 ((int)p1 - (int)p2) under the theory that the narrower operation
4175 is cheaper. */
4177 while (CONVERT_EXPR_P (op0)
4178 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4180 tree inner = TREE_OPERAND (op0, 0);
4181 if (inner == error_mark_node
4182 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4183 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
4184 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4185 break;
4186 op0 = inner;
4189 while (CONVERT_EXPR_P (op1)
4190 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4192 tree inner = TREE_OPERAND (op1, 0);
4193 if (inner == error_mark_node
4194 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4195 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
4196 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4197 break;
4198 op1 = inner;
4201 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4202 if (!op0)
4203 return NULL_TREE;
4205 op1 = initializer_constant_valid_p_1 (op1, endtype,
4206 cache ? cache + 2 : NULL);
4207 /* Both initializers must be known. */
4208 if (op1)
4210 if (op0 == op1
4211 && (op0 == null_pointer_node
4212 || TREE_CODE (value) == MINUS_EXPR))
4213 return null_pointer_node;
4215 /* Support differences between labels. */
4216 if (TREE_CODE (op0) == LABEL_DECL
4217 && TREE_CODE (op1) == LABEL_DECL)
4218 return null_pointer_node;
4220 if (TREE_CODE (op0) == STRING_CST
4221 && TREE_CODE (op1) == STRING_CST
4222 && operand_equal_p (op0, op1, 1))
4223 return null_pointer_node;
4226 return NULL_TREE;
4229 /* Helper function of initializer_constant_valid_p.
4230 Return nonzero if VALUE is a valid constant-valued expression
4231 for use in initializing a static variable; one that can be an
4232 element of a "constant" initializer.
4234 Return null_pointer_node if the value is absolute;
4235 if it is relocatable, return the variable that determines the relocation.
4236 We assume that VALUE has been folded as much as possible;
4237 therefore, we do not need to check for such things as
4238 arithmetic-combinations of integers.
4240 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4242 static tree
4243 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4245 tree ret;
4247 switch (TREE_CODE (value))
4249 case CONSTRUCTOR:
4250 if (constructor_static_from_elts_p (value))
4252 unsigned HOST_WIDE_INT idx;
4253 tree elt;
4254 bool absolute = true;
4256 if (cache && cache[0] == value)
4257 return cache[1];
4258 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4260 tree reloc;
4261 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4262 NULL);
4263 if (!reloc)
4265 if (cache)
4267 cache[0] = value;
4268 cache[1] = NULL_TREE;
4270 return NULL_TREE;
4272 if (reloc != null_pointer_node)
4273 absolute = false;
4275 /* For a non-absolute relocation, there is no single
4276 variable that can be "the variable that determines the
4277 relocation." */
4278 if (cache)
4280 cache[0] = value;
4281 cache[1] = absolute ? null_pointer_node : error_mark_node;
4283 return absolute ? null_pointer_node : error_mark_node;
4286 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4288 case INTEGER_CST:
4289 case VECTOR_CST:
4290 case REAL_CST:
4291 case FIXED_CST:
4292 case STRING_CST:
4293 case COMPLEX_CST:
4294 return null_pointer_node;
4296 case ADDR_EXPR:
4297 case FDESC_EXPR:
4299 tree op0 = staticp (TREE_OPERAND (value, 0));
4300 if (op0)
4302 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4303 to be a constant, this is old-skool offsetof-like nonsense. */
4304 if (TREE_CODE (op0) == INDIRECT_REF
4305 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4306 return null_pointer_node;
4307 /* Taking the address of a nested function involves a trampoline,
4308 unless we don't need or want one. */
4309 if (TREE_CODE (op0) == FUNCTION_DECL
4310 && DECL_STATIC_CHAIN (op0)
4311 && !TREE_NO_TRAMPOLINE (value))
4312 return NULL_TREE;
4313 /* "&{...}" requires a temporary to hold the constructed
4314 object. */
4315 if (TREE_CODE (op0) == CONSTRUCTOR)
4316 return NULL_TREE;
4318 return op0;
4321 case NON_LVALUE_EXPR:
4322 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4323 endtype, cache);
4325 case VIEW_CONVERT_EXPR:
4327 tree src = TREE_OPERAND (value, 0);
4328 tree src_type = TREE_TYPE (src);
4329 tree dest_type = TREE_TYPE (value);
4331 /* Allow view-conversions from aggregate to non-aggregate type only
4332 if the bit pattern is fully preserved afterwards; otherwise, the
4333 RTL expander won't be able to apply a subsequent transformation
4334 to the underlying constructor. */
4335 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4337 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4338 return initializer_constant_valid_p_1 (src, endtype, cache);
4339 else
4340 return NULL_TREE;
4343 /* Allow all other kinds of view-conversion. */
4344 return initializer_constant_valid_p_1 (src, endtype, cache);
4347 CASE_CONVERT:
4349 tree src = TREE_OPERAND (value, 0);
4350 tree src_type = TREE_TYPE (src);
4351 tree dest_type = TREE_TYPE (value);
4353 /* Allow conversions between pointer types, floating-point
4354 types, and offset types. */
4355 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4356 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4357 || (TREE_CODE (dest_type) == OFFSET_TYPE
4358 && TREE_CODE (src_type) == OFFSET_TYPE))
4359 return initializer_constant_valid_p_1 (src, endtype, cache);
4361 /* Allow length-preserving conversions between integer types. */
4362 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4363 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4364 return initializer_constant_valid_p_1 (src, endtype, cache);
4366 /* Allow conversions between other integer types only if
4367 explicit value. */
4368 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type))
4370 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4371 if (inner == null_pointer_node)
4372 return null_pointer_node;
4373 break;
4376 /* Allow (int) &foo provided int is as wide as a pointer. */
4377 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4378 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4379 return initializer_constant_valid_p_1 (src, endtype, cache);
4381 /* Likewise conversions from int to pointers, but also allow
4382 conversions from 0. */
4383 if ((POINTER_TYPE_P (dest_type)
4384 || TREE_CODE (dest_type) == OFFSET_TYPE)
4385 && INTEGRAL_TYPE_P (src_type))
4387 if (TREE_CODE (src) == INTEGER_CST
4388 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4389 return null_pointer_node;
4390 if (integer_zerop (src))
4391 return null_pointer_node;
4392 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4393 return initializer_constant_valid_p_1 (src, endtype, cache);
4396 /* Allow conversions to struct or union types if the value
4397 inside is okay. */
4398 if (TREE_CODE (dest_type) == RECORD_TYPE
4399 || TREE_CODE (dest_type) == UNION_TYPE)
4400 return initializer_constant_valid_p_1 (src, endtype, cache);
4402 break;
4404 case POINTER_PLUS_EXPR:
4405 case PLUS_EXPR:
4406 /* Any valid floating-point constants will have been folded by now;
4407 with -frounding-math we hit this with addition of two constants. */
4408 if (TREE_CODE (endtype) == REAL_TYPE)
4409 return NULL_TREE;
4410 if (cache && cache[0] == value)
4411 return cache[1];
4412 if (! INTEGRAL_TYPE_P (endtype)
4413 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4415 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4416 tree valid0
4417 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4418 endtype, ncache);
4419 tree valid1
4420 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4421 endtype, ncache + 2);
4422 /* If either term is absolute, use the other term's relocation. */
4423 if (valid0 == null_pointer_node)
4424 ret = valid1;
4425 else if (valid1 == null_pointer_node)
4426 ret = valid0;
4427 /* Support narrowing pointer differences. */
4428 else
4429 ret = narrowing_initializer_constant_valid_p (value, endtype,
4430 ncache);
4432 else
4433 /* Support narrowing pointer differences. */
4434 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4435 if (cache)
4437 cache[0] = value;
4438 cache[1] = ret;
4440 return ret;
4442 case MINUS_EXPR:
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 /* Win if second argument is absolute. */
4458 if (valid1 == null_pointer_node)
4459 ret = valid0;
4460 /* Win if both arguments have the same relocation.
4461 Then the value is absolute. */
4462 else if (valid0 == valid1 && valid0 != 0)
4463 ret = null_pointer_node;
4464 /* Since GCC guarantees that string constants are unique in the
4465 generated code, a subtraction between two copies of the same
4466 constant string is absolute. */
4467 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4468 && valid1 && TREE_CODE (valid1) == STRING_CST
4469 && operand_equal_p (valid0, valid1, 1))
4470 ret = null_pointer_node;
4471 /* Support narrowing differences. */
4472 else
4473 ret = narrowing_initializer_constant_valid_p (value, endtype,
4474 ncache);
4476 else
4477 /* Support narrowing differences. */
4478 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4479 if (cache)
4481 cache[0] = value;
4482 cache[1] = ret;
4484 return ret;
4486 default:
4487 break;
4490 return NULL_TREE;
4493 /* Return nonzero if VALUE is a valid constant-valued expression
4494 for use in initializing a static variable; one that can be an
4495 element of a "constant" initializer.
4497 Return null_pointer_node if the value is absolute;
4498 if it is relocatable, return the variable that determines the relocation.
4499 We assume that VALUE has been folded as much as possible;
4500 therefore, we do not need to check for such things as
4501 arithmetic-combinations of integers. */
4502 tree
4503 initializer_constant_valid_p (tree value, tree endtype)
4505 return initializer_constant_valid_p_1 (value, endtype, NULL);
4508 /* Return true if VALUE is a valid constant-valued expression
4509 for use in initializing a static bit-field; one that can be
4510 an element of a "constant" initializer. */
4512 bool
4513 initializer_constant_valid_for_bitfield_p (tree value)
4515 /* For bitfields we support integer constants or possibly nested aggregates
4516 of such. */
4517 switch (TREE_CODE (value))
4519 case CONSTRUCTOR:
4521 unsigned HOST_WIDE_INT idx;
4522 tree elt;
4524 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4525 if (!initializer_constant_valid_for_bitfield_p (elt))
4526 return false;
4527 return true;
4530 case INTEGER_CST:
4531 case REAL_CST:
4532 return true;
4534 case VIEW_CONVERT_EXPR:
4535 case NON_LVALUE_EXPR:
4536 return
4537 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4539 default:
4540 break;
4543 return false;
4546 /* output_constructor outer state of relevance in recursive calls, typically
4547 for nested aggregate bitfields. */
4549 typedef struct {
4550 unsigned int bit_offset; /* current position in ... */
4551 int byte; /* ... the outer byte buffer. */
4552 } oc_outer_state;
4554 static unsigned HOST_WIDE_INT
4555 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int,
4556 oc_outer_state *);
4558 /* Output assembler code for constant EXP, with no label.
4559 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4560 Assumes output_addressed_constants has been done on EXP already.
4562 Generate at least SIZE bytes of assembler data, padding at the end
4563 with zeros if necessary. SIZE must always be specified. The returned
4564 value is the actual number of bytes of assembler data generated, which
4565 may be bigger than SIZE if the object contains a variable length field.
4567 SIZE is important for structure constructors,
4568 since trailing members may have been omitted from the constructor.
4569 It is also important for initialization of arrays from string constants
4570 since the full length of the string constant might not be wanted.
4571 It is also needed for initialization of unions, where the initializer's
4572 type is just one member, and that may not be as long as the union.
4574 There a case in which we would fail to output exactly SIZE bytes:
4575 for a structure constructor that wants to produce more than SIZE bytes.
4576 But such constructors will never be generated for any possible input.
4578 ALIGN is the alignment of the data in bits. */
4580 static unsigned HOST_WIDE_INT
4581 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align)
4583 enum tree_code code;
4584 unsigned HOST_WIDE_INT thissize;
4586 if (size == 0 || flag_syntax_only)
4587 return size;
4589 /* See if we're trying to initialize a pointer in a non-default mode
4590 to the address of some declaration somewhere. If the target says
4591 the mode is valid for pointers, assume the target has a way of
4592 resolving it. */
4593 if (TREE_CODE (exp) == NOP_EXPR
4594 && POINTER_TYPE_P (TREE_TYPE (exp))
4595 && targetm.addr_space.valid_pointer_mode
4596 (TYPE_MODE (TREE_TYPE (exp)),
4597 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4599 tree saved_type = TREE_TYPE (exp);
4601 /* Peel off any intermediate conversions-to-pointer for valid
4602 pointer modes. */
4603 while (TREE_CODE (exp) == NOP_EXPR
4604 && POINTER_TYPE_P (TREE_TYPE (exp))
4605 && targetm.addr_space.valid_pointer_mode
4606 (TYPE_MODE (TREE_TYPE (exp)),
4607 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4608 exp = TREE_OPERAND (exp, 0);
4610 /* If what we're left with is the address of something, we can
4611 convert the address to the final type and output it that
4612 way. */
4613 if (TREE_CODE (exp) == ADDR_EXPR)
4614 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4615 /* Likewise for constant ints. */
4616 else if (TREE_CODE (exp) == INTEGER_CST)
4617 exp = wide_int_to_tree (saved_type, exp);
4621 /* Eliminate any conversions since we'll be outputting the underlying
4622 constant. */
4623 while (CONVERT_EXPR_P (exp)
4624 || TREE_CODE (exp) == NON_LVALUE_EXPR
4625 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4627 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4628 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4630 /* Make sure eliminating the conversion is really a no-op, except with
4631 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4632 union types to allow for Ada unchecked unions. */
4633 if (type_size > op_size
4634 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4635 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4636 /* Keep the conversion. */
4637 break;
4638 else
4639 exp = TREE_OPERAND (exp, 0);
4642 code = TREE_CODE (TREE_TYPE (exp));
4643 thissize = int_size_in_bytes (TREE_TYPE (exp));
4645 /* Allow a constructor with no elements for any data type.
4646 This means to fill the space with zeros. */
4647 if (TREE_CODE (exp) == CONSTRUCTOR
4648 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4650 assemble_zeros (size);
4651 return size;
4654 if (TREE_CODE (exp) == FDESC_EXPR)
4656 #ifdef ASM_OUTPUT_FDESC
4657 HOST_WIDE_INT part = tree_to_shwi (TREE_OPERAND (exp, 1));
4658 tree decl = TREE_OPERAND (exp, 0);
4659 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4660 #else
4661 gcc_unreachable ();
4662 #endif
4663 return size;
4666 /* Now output the underlying data. If we've handling the padding, return.
4667 Otherwise, break and ensure SIZE is the size written. */
4668 switch (code)
4670 case BOOLEAN_TYPE:
4671 case INTEGER_TYPE:
4672 case ENUMERAL_TYPE:
4673 case POINTER_TYPE:
4674 case REFERENCE_TYPE:
4675 case OFFSET_TYPE:
4676 case FIXED_POINT_TYPE:
4677 case NULLPTR_TYPE:
4678 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
4679 EXPAND_INITIALIZER),
4680 MIN (size, thissize), align, 0))
4681 error ("initializer for integer/fixed-point value is too complicated");
4682 break;
4684 case REAL_TYPE:
4685 if (TREE_CODE (exp) != REAL_CST)
4686 error ("initializer for floating value is not a floating constant");
4687 else
4688 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)), align);
4689 break;
4691 case COMPLEX_TYPE:
4692 output_constant (TREE_REALPART (exp), thissize / 2, align);
4693 output_constant (TREE_IMAGPART (exp), thissize / 2,
4694 min_align (align, BITS_PER_UNIT * (thissize / 2)));
4695 break;
4697 case ARRAY_TYPE:
4698 case VECTOR_TYPE:
4699 switch (TREE_CODE (exp))
4701 case CONSTRUCTOR:
4702 return output_constructor (exp, size, align, NULL);
4703 case STRING_CST:
4704 thissize
4705 = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4706 assemble_string (TREE_STRING_POINTER (exp), thissize);
4707 break;
4708 case VECTOR_CST:
4710 enum machine_mode inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4711 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4712 int elt_size = GET_MODE_SIZE (inner);
4713 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align);
4714 thissize = elt_size;
4715 for (unsigned int i = 1; i < VECTOR_CST_NELTS (exp); i++)
4717 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign);
4718 thissize += elt_size;
4720 break;
4722 default:
4723 gcc_unreachable ();
4725 break;
4727 case RECORD_TYPE:
4728 case UNION_TYPE:
4729 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4730 return output_constructor (exp, size, align, NULL);
4732 case ERROR_MARK:
4733 return 0;
4735 default:
4736 gcc_unreachable ();
4739 if (size > thissize)
4740 assemble_zeros (size - thissize);
4742 return size;
4746 /* Subroutine of output_constructor, used for computing the size of
4747 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4748 type with an unspecified upper bound. */
4750 static unsigned HOST_WIDE_INT
4751 array_size_for_constructor (tree val)
4753 tree max_index;
4754 unsigned HOST_WIDE_INT cnt;
4755 tree index, value, tmp;
4756 offset_int i;
4758 /* This code used to attempt to handle string constants that are not
4759 arrays of single-bytes, but nothing else does, so there's no point in
4760 doing it here. */
4761 if (TREE_CODE (val) == STRING_CST)
4762 return TREE_STRING_LENGTH (val);
4764 max_index = NULL_TREE;
4765 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
4767 if (TREE_CODE (index) == RANGE_EXPR)
4768 index = TREE_OPERAND (index, 1);
4769 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
4770 max_index = index;
4773 if (max_index == NULL_TREE)
4774 return 0;
4776 /* Compute the total number of array elements. */
4777 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
4778 i = wi::to_offset (max_index) - wi::to_offset (tmp) + 1;
4780 /* Multiply by the array element unit size to find number of bytes. */
4781 i *= wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
4783 gcc_assert (wi::fits_uhwi_p (i));
4784 return i.to_uhwi ();
4787 /* Other datastructures + helpers for output_constructor. */
4789 /* output_constructor local state to support interaction with helpers. */
4791 typedef struct {
4793 /* Received arguments. */
4794 tree exp; /* Constructor expression. */
4795 tree type; /* Type of constructor expression. */
4796 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */
4797 unsigned int align; /* Known initial alignment. */
4798 tree min_index; /* Lower bound if specified for an array. */
4800 /* Output processing state. */
4801 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */
4802 int byte; /* Part of a bitfield byte yet to be output. */
4803 int last_relative_index; /* Implicit or explicit index of the last
4804 array element output within a bitfield. */
4805 bool byte_buffer_in_use; /* Whether BYTE is in use. */
4807 /* Current element. */
4808 tree field; /* Current field decl in a record. */
4809 tree val; /* Current element value. */
4810 tree index; /* Current element index. */
4812 } oc_local_state;
4814 /* Helper for output_constructor. From the current LOCAL state, output a
4815 RANGE_EXPR element. */
4817 static void
4818 output_constructor_array_range (oc_local_state *local)
4820 unsigned HOST_WIDE_INT fieldsize
4821 = int_size_in_bytes (TREE_TYPE (local->type));
4823 HOST_WIDE_INT lo_index
4824 = tree_to_shwi (TREE_OPERAND (local->index, 0));
4825 HOST_WIDE_INT hi_index
4826 = tree_to_shwi (TREE_OPERAND (local->index, 1));
4827 HOST_WIDE_INT index;
4829 unsigned int align2
4830 = min_align (local->align, fieldsize * BITS_PER_UNIT);
4832 for (index = lo_index; index <= hi_index; index++)
4834 /* Output the element's initial value. */
4835 if (local->val == NULL_TREE)
4836 assemble_zeros (fieldsize);
4837 else
4838 fieldsize = output_constant (local->val, fieldsize, align2);
4840 /* Count its size. */
4841 local->total_bytes += fieldsize;
4845 /* Helper for output_constructor. From the current LOCAL state, output a
4846 field element that is not true bitfield or part of an outer one. */
4848 static void
4849 output_constructor_regular_field (oc_local_state *local)
4851 /* Field size and position. Since this structure is static, we know the
4852 positions are constant. */
4853 unsigned HOST_WIDE_INT fieldsize;
4854 HOST_WIDE_INT fieldpos;
4856 unsigned int align2;
4858 if (local->index != NULL_TREE)
4860 /* Perform the index calculation in modulo arithmetic but
4861 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
4862 but we are using an unsigned sizetype. */
4863 unsigned prec = TYPE_PRECISION (sizetype);
4864 offset_int idx = wi::sext (wi::to_offset (local->index)
4865 - wi::to_offset (local->min_index), prec);
4866 fieldpos = (idx * wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (local->val))))
4867 .to_short_addr ();
4869 else if (local->field != NULL_TREE)
4870 fieldpos = int_byte_position (local->field);
4871 else
4872 fieldpos = 0;
4874 /* Output any buffered-up bit-fields preceding this element. */
4875 if (local->byte_buffer_in_use)
4877 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4878 local->total_bytes++;
4879 local->byte_buffer_in_use = false;
4882 /* Advance to offset of this element.
4883 Note no alignment needed in an array, since that is guaranteed
4884 if each element has the proper size. */
4885 if ((local->field != NULL_TREE || local->index != NULL_TREE)
4886 && fieldpos > local->total_bytes)
4888 assemble_zeros (fieldpos - local->total_bytes);
4889 local->total_bytes = fieldpos;
4892 /* Find the alignment of this element. */
4893 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
4895 /* Determine size this element should occupy. */
4896 if (local->field)
4898 fieldsize = 0;
4900 /* If this is an array with an unspecified upper bound,
4901 the initializer determines the size. */
4902 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
4903 but we cannot do this until the deprecated support for
4904 initializing zero-length array members is removed. */
4905 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
4906 && TYPE_DOMAIN (TREE_TYPE (local->field))
4907 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field))))
4909 fieldsize = array_size_for_constructor (local->val);
4910 /* Given a non-empty initialization, this field had
4911 better be last. */
4912 gcc_assert (!fieldsize || !DECL_CHAIN (local->field));
4914 else
4915 fieldsize = tree_to_uhwi (DECL_SIZE_UNIT (local->field));
4917 else
4918 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
4920 /* Output the element's initial value. */
4921 if (local->val == NULL_TREE)
4922 assemble_zeros (fieldsize);
4923 else
4924 fieldsize = output_constant (local->val, fieldsize, align2);
4926 /* Count its size. */
4927 local->total_bytes += fieldsize;
4930 /* Helper for output_constructor. From the LOCAL state, output an element
4931 that is a true bitfield or part of an outer one. BIT_OFFSET is the offset
4932 from the start of a possibly ongoing outer byte buffer. */
4934 static void
4935 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
4937 /* Bit size of this element. */
4938 HOST_WIDE_INT ebitsize
4939 = (local->field
4940 ? tree_to_uhwi (DECL_SIZE (local->field))
4941 : tree_to_uhwi (TYPE_SIZE (TREE_TYPE (local->type))));
4943 /* Relative index of this element if this is an array component. */
4944 HOST_WIDE_INT relative_index
4945 = (!local->field
4946 ? (local->index
4947 ? (tree_to_shwi (local->index)
4948 - tree_to_shwi (local->min_index))
4949 : local->last_relative_index + 1)
4950 : 0);
4952 /* Bit position of this element from the start of the containing
4953 constructor. */
4954 HOST_WIDE_INT constructor_relative_ebitpos
4955 = (local->field
4956 ? int_bit_position (local->field)
4957 : ebitsize * relative_index);
4959 /* Bit position of this element from the start of a possibly ongoing
4960 outer byte buffer. */
4961 HOST_WIDE_INT byte_relative_ebitpos
4962 = bit_offset + constructor_relative_ebitpos;
4964 /* From the start of a possibly ongoing outer byte buffer, offsets to
4965 the first bit of this element and to the first bit past the end of
4966 this element. */
4967 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
4968 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
4970 local->last_relative_index = relative_index;
4972 if (local->val == NULL_TREE)
4973 local->val = integer_zero_node;
4975 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
4976 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
4977 local->val = TREE_OPERAND (local->val, 0);
4979 if (TREE_CODE (local->val) != INTEGER_CST
4980 && TREE_CODE (local->val) != CONSTRUCTOR)
4982 error ("invalid initial value for member %qE", DECL_NAME (local->field));
4983 return;
4986 /* If this field does not start in this (or next) byte, skip some bytes. */
4987 if (next_offset / BITS_PER_UNIT != local->total_bytes)
4989 /* Output remnant of any bit field in previous bytes. */
4990 if (local->byte_buffer_in_use)
4992 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4993 local->total_bytes++;
4994 local->byte_buffer_in_use = false;
4997 /* If still not at proper byte, advance to there. */
4998 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5000 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
5001 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
5002 local->total_bytes = next_offset / BITS_PER_UNIT;
5006 /* Set up the buffer if necessary. */
5007 if (!local->byte_buffer_in_use)
5009 local->byte = 0;
5010 if (ebitsize > 0)
5011 local->byte_buffer_in_use = true;
5014 /* If this is nested constructor, recurse passing the bit offset and the
5015 pending data, then retrieve the new pending data afterwards. */
5016 if (TREE_CODE (local->val) == CONSTRUCTOR)
5018 oc_outer_state temp_state;
5019 temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5020 temp_state.byte = local->byte;
5021 local->total_bytes
5022 += output_constructor (local->val, 0, 0, &temp_state);
5023 local->byte = temp_state.byte;
5024 return;
5027 /* Otherwise, we must split the element into pieces that fall within
5028 separate bytes, and combine each byte with previous or following
5029 bit-fields. */
5030 while (next_offset < end_offset)
5032 int this_time;
5033 int shift;
5034 HOST_WIDE_INT value;
5035 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5036 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5038 /* Advance from byte to byte within this element when necessary. */
5039 while (next_byte != local->total_bytes)
5041 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5042 local->total_bytes++;
5043 local->byte = 0;
5046 /* Number of bits we can process at once (all part of the same byte). */
5047 this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5048 if (BYTES_BIG_ENDIAN)
5050 /* On big-endian machine, take the most significant bits (of the
5051 bits that are significant) first and put them into bytes from
5052 the most significant end. */
5053 shift = end_offset - next_offset - this_time;
5055 /* Don't try to take a bunch of bits that cross
5056 the word boundary in the INTEGER_CST. We can
5057 only select bits from one element. */
5058 if ((shift / HOST_BITS_PER_WIDE_INT)
5059 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5061 const int end = shift + this_time - 1;
5062 shift = end & -HOST_BITS_PER_WIDE_INT;
5063 this_time = end - shift + 1;
5066 /* Now get the bits from the appropriate constant word. */
5067 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5068 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5070 /* Get the result. This works only when:
5071 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5072 local->byte |= (((value >> shift)
5073 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5074 << (BITS_PER_UNIT - this_time - next_bit));
5076 else
5078 /* On little-endian machines, take the least significant bits of
5079 the value first and pack them starting at the least significant
5080 bits of the bytes. */
5081 shift = next_offset - byte_relative_ebitpos;
5083 /* Don't try to take a bunch of bits that cross
5084 the word boundary in the INTEGER_CST. We can
5085 only select bits from one element. */
5086 if ((shift / HOST_BITS_PER_WIDE_INT)
5087 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5088 this_time
5089 = HOST_BITS_PER_WIDE_INT - (shift & (HOST_BITS_PER_WIDE_INT - 1));
5091 /* Now get the bits from the appropriate constant word. */
5092 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5093 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5095 /* Get the result. This works only when:
5096 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5097 local->byte |= (((value >> shift)
5098 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5099 << next_bit);
5102 next_offset += this_time;
5103 local->byte_buffer_in_use = true;
5107 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5108 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5109 caller output state of relevance in recursive invocations. */
5111 static unsigned HOST_WIDE_INT
5112 output_constructor (tree exp, unsigned HOST_WIDE_INT size,
5113 unsigned int align, oc_outer_state *outer)
5115 unsigned HOST_WIDE_INT cnt;
5116 constructor_elt *ce;
5118 oc_local_state local;
5120 /* Setup our local state to communicate with helpers. */
5121 local.exp = exp;
5122 local.type = TREE_TYPE (exp);
5123 local.size = size;
5124 local.align = align;
5125 if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5126 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5127 else
5128 local.min_index = NULL_TREE;
5130 local.total_bytes = 0;
5131 local.byte_buffer_in_use = outer != NULL;
5132 local.byte = outer ? outer->byte : 0;
5133 local.last_relative_index = -1;
5135 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5137 /* As CE goes through the elements of the constant, FIELD goes through the
5138 structure fields if the constant is a structure. If the constant is a
5139 union, we override this by getting the field from the TREE_LIST element.
5140 But the constant could also be an array. Then FIELD is zero.
5142 There is always a maximum of one element in the chain LINK for unions
5143 (even if the initializer in a source program incorrectly contains
5144 more one). */
5146 if (TREE_CODE (local.type) == RECORD_TYPE)
5147 local.field = TYPE_FIELDS (local.type);
5148 else
5149 local.field = NULL_TREE;
5151 for (cnt = 0;
5152 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5153 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5155 local.val = ce->value;
5156 local.index = NULL_TREE;
5158 /* The element in a union constructor specifies the proper field
5159 or index. */
5160 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5161 local.field = ce->index;
5163 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5164 local.index = ce->index;
5166 if (local.field && flag_verbose_asm)
5167 fprintf (asm_out_file, "%s %s:\n",
5168 ASM_COMMENT_START,
5169 DECL_NAME (local.field)
5170 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5171 : "<anonymous>");
5173 /* Eliminate the marker that makes a cast not be an lvalue. */
5174 if (local.val != NULL_TREE)
5175 STRIP_NOPS (local.val);
5177 /* Output the current element, using the appropriate helper ... */
5179 /* For an array slice not part of an outer bitfield. */
5180 if (!outer
5181 && local.index != NULL_TREE
5182 && TREE_CODE (local.index) == RANGE_EXPR)
5183 output_constructor_array_range (&local);
5185 /* For a field that is neither a true bitfield nor part of an outer one,
5186 known to be at least byte aligned and multiple-of-bytes long. */
5187 else if (!outer
5188 && (local.field == NULL_TREE
5189 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5190 output_constructor_regular_field (&local);
5192 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5193 supported for scalar fields, so we may need to convert first. */
5194 else
5196 if (TREE_CODE (local.val) == REAL_CST)
5197 local.val
5198 = fold_unary (VIEW_CONVERT_EXPR,
5199 build_nonstandard_integer_type
5200 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5201 local.val);
5202 output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5206 /* If we are not at toplevel, save the pending data for our caller.
5207 Otherwise output the pending data and padding zeros as needed. */
5208 if (outer)
5209 outer->byte = local.byte;
5210 else
5212 if (local.byte_buffer_in_use)
5214 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5215 local.total_bytes++;
5218 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5220 assemble_zeros (local.size - local.total_bytes);
5221 local.total_bytes = local.size;
5225 return local.total_bytes;
5228 /* Mark DECL as weak. */
5230 static void
5231 mark_weak (tree decl)
5233 DECL_WEAK (decl) = 1;
5235 if (DECL_RTL_SET_P (decl)
5236 && MEM_P (DECL_RTL (decl))
5237 && XEXP (DECL_RTL (decl), 0)
5238 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5239 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5242 /* Merge weak status between NEWDECL and OLDDECL. */
5244 void
5245 merge_weak (tree newdecl, tree olddecl)
5247 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5249 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5251 tree *pwd;
5252 /* We put the NEWDECL on the weak_decls list at some point
5253 and OLDDECL as well. Keep just OLDDECL on the list. */
5254 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5255 if (TREE_VALUE (*pwd) == newdecl)
5257 *pwd = TREE_CHAIN (*pwd);
5258 break;
5261 return;
5264 if (DECL_WEAK (newdecl))
5266 tree wd;
5268 /* NEWDECL is weak, but OLDDECL is not. */
5270 /* If we already output the OLDDECL, we're in trouble; we can't
5271 go back and make it weak. This should never happen in
5272 unit-at-a-time compilation. */
5273 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5275 /* If we've already generated rtl referencing OLDDECL, we may
5276 have done so in a way that will not function properly with
5277 a weak symbol. Again in unit-at-a-time this should be
5278 impossible. */
5279 gcc_assert (!TREE_USED (olddecl)
5280 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5282 if (TARGET_SUPPORTS_WEAK)
5284 /* We put the NEWDECL on the weak_decls list at some point.
5285 Replace it with the OLDDECL. */
5286 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5287 if (TREE_VALUE (wd) == newdecl)
5289 TREE_VALUE (wd) = olddecl;
5290 break;
5292 /* We may not find the entry on the list. If NEWDECL is a
5293 weak alias, then we will have already called
5294 globalize_decl to remove the entry; in that case, we do
5295 not need to do anything. */
5298 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5299 mark_weak (olddecl);
5301 else
5302 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5303 weak. Just update NEWDECL to indicate that it's weak too. */
5304 mark_weak (newdecl);
5307 /* Declare DECL to be a weak symbol. */
5309 void
5310 declare_weak (tree decl)
5312 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5313 if (! TREE_PUBLIC (decl))
5314 error ("weak declaration of %q+D must be public", decl);
5315 else if (!TARGET_SUPPORTS_WEAK)
5316 warning (0, "weak declaration of %q+D not supported", decl);
5318 mark_weak (decl);
5319 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5320 DECL_ATTRIBUTES (decl)
5321 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5324 static void
5325 weak_finish_1 (tree decl)
5327 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5328 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5329 #endif
5331 if (! TREE_USED (decl))
5332 return;
5334 #ifdef ASM_WEAKEN_DECL
5335 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5336 #else
5337 #ifdef ASM_WEAKEN_LABEL
5338 ASM_WEAKEN_LABEL (asm_out_file, name);
5339 #else
5340 #ifdef ASM_OUTPUT_WEAK_ALIAS
5342 static bool warn_once = 0;
5343 if (! warn_once)
5345 warning (0, "only weak aliases are supported in this configuration");
5346 warn_once = 1;
5348 return;
5350 #endif
5351 #endif
5352 #endif
5355 /* Fiven an assembly name, find the decl it is associated with. */
5356 static tree
5357 find_decl (tree target)
5359 symtab_node *node = symtab_node::get_for_asmname (target);
5360 if (node)
5361 return node->decl;
5362 return NULL_TREE;
5365 /* This TREE_LIST contains weakref targets. */
5367 static GTY(()) tree weakref_targets;
5369 /* Emit any pending weak declarations. */
5371 void
5372 weak_finish (void)
5374 tree t;
5376 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5378 tree alias_decl = TREE_PURPOSE (t);
5379 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5381 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5382 /* Remove alias_decl from the weak list, but leave entries for
5383 the target alone. */
5384 target = NULL_TREE;
5385 #ifndef ASM_OUTPUT_WEAKREF
5386 else if (! TREE_SYMBOL_REFERENCED (target))
5388 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5389 defined, otherwise we and weak_finish_1 would use
5390 different macros. */
5391 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5392 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5393 # else
5394 tree decl = find_decl (target);
5396 if (! decl)
5398 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5399 TREE_CODE (alias_decl), target,
5400 TREE_TYPE (alias_decl));
5402 DECL_EXTERNAL (decl) = 1;
5403 TREE_PUBLIC (decl) = 1;
5404 DECL_ARTIFICIAL (decl) = 1;
5405 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5406 TREE_USED (decl) = 1;
5409 weak_finish_1 (decl);
5410 # endif
5412 #endif
5415 tree *p;
5416 tree t2;
5418 /* Remove the alias and the target from the pending weak list
5419 so that we do not emit any .weak directives for the former,
5420 nor multiple .weak directives for the latter. */
5421 for (p = &weak_decls; (t2 = *p) ; )
5423 if (TREE_VALUE (t2) == alias_decl
5424 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5425 *p = TREE_CHAIN (t2);
5426 else
5427 p = &TREE_CHAIN (t2);
5430 /* Remove other weakrefs to the same target, to speed things up. */
5431 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5433 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5434 *p = TREE_CHAIN (t2);
5435 else
5436 p = &TREE_CHAIN (t2);
5441 for (t = weak_decls; t; t = TREE_CHAIN (t))
5443 tree decl = TREE_VALUE (t);
5445 weak_finish_1 (decl);
5449 /* Emit the assembly bits to indicate that DECL is globally visible. */
5451 static void
5452 globalize_decl (tree decl)
5455 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5456 if (DECL_WEAK (decl))
5458 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5459 tree *p, t;
5461 #ifdef ASM_WEAKEN_DECL
5462 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5463 #else
5464 ASM_WEAKEN_LABEL (asm_out_file, name);
5465 #endif
5467 /* Remove this function from the pending weak list so that
5468 we do not emit multiple .weak directives for it. */
5469 for (p = &weak_decls; (t = *p) ; )
5471 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5472 *p = TREE_CHAIN (t);
5473 else
5474 p = &TREE_CHAIN (t);
5477 /* Remove weakrefs to the same target from the pending weakref
5478 list, for the same reason. */
5479 for (p = &weakref_targets; (t = *p) ; )
5481 if (DECL_ASSEMBLER_NAME (decl)
5482 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5483 *p = TREE_CHAIN (t);
5484 else
5485 p = &TREE_CHAIN (t);
5488 return;
5490 #endif
5492 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5495 vec<alias_pair, va_gc> *alias_pairs;
5497 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5498 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5499 tree node is DECL to have the value of the tree node TARGET. */
5501 void
5502 do_assemble_alias (tree decl, tree target)
5504 /* Emulated TLS had better not get this var. */
5505 gcc_assert (!(!targetm.have_tls
5506 && TREE_CODE (decl) == VAR_DECL
5507 && DECL_THREAD_LOCAL_P (decl)));
5509 if (TREE_ASM_WRITTEN (decl))
5510 return;
5512 /* We must force creation of DECL_RTL for debug info generation, even though
5513 we don't use it here. */
5514 make_decl_rtl (decl);
5516 TREE_ASM_WRITTEN (decl) = 1;
5517 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5519 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5521 ultimate_transparent_alias_target (&target);
5523 if (!TREE_SYMBOL_REFERENCED (target))
5524 weakref_targets = tree_cons (decl, target, weakref_targets);
5526 #ifdef ASM_OUTPUT_WEAKREF
5527 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5528 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5529 IDENTIFIER_POINTER (target));
5530 #else
5531 if (!TARGET_SUPPORTS_WEAK)
5533 error_at (DECL_SOURCE_LOCATION (decl),
5534 "weakref is not supported in this configuration");
5535 return;
5537 #endif
5538 return;
5541 #ifdef ASM_OUTPUT_DEF
5542 /* Make name accessible from other files, if appropriate. */
5544 if (TREE_PUBLIC (decl))
5546 globalize_decl (decl);
5547 maybe_assemble_visibility (decl);
5549 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5551 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5552 if (targetm.has_ifunc_p ())
5553 ASM_OUTPUT_TYPE_DIRECTIVE
5554 (asm_out_file, IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5555 IFUNC_ASM_TYPE);
5556 else
5557 #endif
5558 error_at (DECL_SOURCE_LOCATION (decl),
5559 "ifunc is not supported on this target");
5562 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5563 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5564 # else
5565 ASM_OUTPUT_DEF (asm_out_file,
5566 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5567 IDENTIFIER_POINTER (target));
5568 # endif
5569 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5571 const char *name;
5572 tree *p, t;
5574 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5575 # ifdef ASM_WEAKEN_DECL
5576 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5577 # else
5578 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5579 # endif
5580 /* Remove this function from the pending weak list so that
5581 we do not emit multiple .weak directives for it. */
5582 for (p = &weak_decls; (t = *p) ; )
5583 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5584 *p = TREE_CHAIN (t);
5585 else
5586 p = &TREE_CHAIN (t);
5588 /* Remove weakrefs to the same target from the pending weakref
5589 list, for the same reason. */
5590 for (p = &weakref_targets; (t = *p) ; )
5592 if (DECL_ASSEMBLER_NAME (decl)
5593 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5594 *p = TREE_CHAIN (t);
5595 else
5596 p = &TREE_CHAIN (t);
5599 #endif
5602 /* Emit an assembler directive to make the symbol for DECL an alias to
5603 the symbol for TARGET. */
5605 void
5606 assemble_alias (tree decl, tree target)
5608 tree target_decl;
5610 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5612 tree alias = DECL_ASSEMBLER_NAME (decl);
5614 ultimate_transparent_alias_target (&target);
5616 if (alias == target)
5617 error ("weakref %q+D ultimately targets itself", decl);
5618 if (TREE_PUBLIC (decl))
5619 error ("weakref %q+D must have static linkage", decl);
5621 else
5623 #if !defined (ASM_OUTPUT_DEF)
5624 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5625 error_at (DECL_SOURCE_LOCATION (decl),
5626 "alias definitions not supported in this configuration");
5627 TREE_ASM_WRITTEN (decl) = 1;
5628 return;
5629 # else
5630 if (!DECL_WEAK (decl))
5632 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5633 error_at (DECL_SOURCE_LOCATION (decl),
5634 "ifunc is not supported in this configuration");
5635 else
5636 error_at (DECL_SOURCE_LOCATION (decl),
5637 "only weak aliases are supported in this configuration");
5638 TREE_ASM_WRITTEN (decl) = 1;
5639 return;
5641 # endif
5642 #endif
5644 TREE_USED (decl) = 1;
5646 /* Allow aliases to aliases. */
5647 if (TREE_CODE (decl) == FUNCTION_DECL)
5648 cgraph_node::get_create (decl)->alias = true;
5649 else
5650 varpool_node::get_create (decl)->alias = true;
5652 /* If the target has already been emitted, we don't have to queue the
5653 alias. This saves a tad of memory. */
5654 if (symtab->global_info_ready)
5655 target_decl = find_decl (target);
5656 else
5657 target_decl= NULL;
5658 if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5659 || symtab->state >= EXPANSION)
5660 do_assemble_alias (decl, target);
5661 else
5663 alias_pair p = {decl, target};
5664 vec_safe_push (alias_pairs, p);
5668 /* Record and output a table of translations from original function
5669 to its transaction aware clone. Note that tm_pure functions are
5670 considered to be their own clone. */
5672 static GTY((if_marked ("tree_map_marked_p"), param_is (struct tree_map)))
5673 htab_t tm_clone_hash;
5675 void
5676 record_tm_clone_pair (tree o, tree n)
5678 struct tree_map **slot, *h;
5680 if (tm_clone_hash == NULL)
5681 tm_clone_hash = htab_create_ggc (32, tree_map_hash, tree_map_eq, 0);
5683 h = ggc_alloc<tree_map> ();
5684 h->hash = htab_hash_pointer (o);
5685 h->base.from = o;
5686 h->to = n;
5688 slot = (struct tree_map **)
5689 htab_find_slot_with_hash (tm_clone_hash, h, h->hash, INSERT);
5690 *slot = h;
5693 tree
5694 get_tm_clone_pair (tree o)
5696 if (tm_clone_hash)
5698 struct tree_map *h, in;
5700 in.base.from = o;
5701 in.hash = htab_hash_pointer (o);
5702 h = (struct tree_map *) htab_find_with_hash (tm_clone_hash,
5703 &in, in.hash);
5704 if (h)
5705 return h->to;
5707 return NULL_TREE;
5710 typedef struct tm_alias_pair
5712 unsigned int uid;
5713 tree from;
5714 tree to;
5715 } tm_alias_pair;
5718 /* Helper function for finish_tm_clone_pairs. Dump a hash table entry
5719 into a VEC in INFO. */
5721 static int
5722 dump_tm_clone_to_vec (void **slot, void *info)
5724 struct tree_map *map = (struct tree_map *) *slot;
5725 vec<tm_alias_pair> *tm_alias_pairs = (vec<tm_alias_pair> *) info;
5726 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
5727 tm_alias_pairs->safe_push (p);
5728 return 1;
5731 /* Dump the actual pairs to the .tm_clone_table section. */
5733 static void
5734 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
5736 unsigned i;
5737 tm_alias_pair *p;
5738 bool switched = false;
5740 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
5742 tree src = p->from;
5743 tree dst = p->to;
5744 struct cgraph_node *src_n = cgraph_node::get (src);
5745 struct cgraph_node *dst_n = cgraph_node::get (dst);
5747 /* The function ipa_tm_create_version() marks the clone as needed if
5748 the original function was needed. But we also mark the clone as
5749 needed if we ever called the clone indirectly through
5750 TM_GETTMCLONE. If neither of these are true, we didn't generate
5751 a clone, and we didn't call it indirectly... no sense keeping it
5752 in the clone table. */
5753 if (!dst_n || !dst_n->definition)
5754 continue;
5756 /* This covers the case where we have optimized the original
5757 function away, and only access the transactional clone. */
5758 if (!src_n || !src_n->definition)
5759 continue;
5761 if (!switched)
5763 switch_to_section (targetm.asm_out.tm_clone_table_section ());
5764 assemble_align (POINTER_SIZE);
5765 switched = true;
5768 assemble_integer (XEXP (DECL_RTL (src), 0),
5769 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
5770 assemble_integer (XEXP (DECL_RTL (dst), 0),
5771 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
5775 /* Provide a default for the tm_clone_table section. */
5777 section *
5778 default_clone_table_section (void)
5780 return get_named_section (NULL, ".tm_clone_table", 3);
5783 /* Helper comparison function for qsorting by the DECL_UID stored in
5784 alias_pair->emitted_diags. */
5786 static int
5787 tm_alias_pair_cmp (const void *x, const void *y)
5789 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
5790 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
5791 if (p1->uid < p2->uid)
5792 return -1;
5793 if (p1->uid > p2->uid)
5794 return 1;
5795 return 0;
5798 void
5799 finish_tm_clone_pairs (void)
5801 vec<tm_alias_pair> tm_alias_pairs = vNULL;
5803 if (tm_clone_hash == NULL)
5804 return;
5806 /* We need a determenistic order for the .tm_clone_table, otherwise
5807 we will get bootstrap comparison failures, so dump the hash table
5808 to a vector, sort it, and dump the vector. */
5810 /* Dump the hashtable to a vector. */
5811 htab_traverse_noresize (tm_clone_hash, dump_tm_clone_to_vec,
5812 (void *) &tm_alias_pairs);
5813 /* Sort it. */
5814 tm_alias_pairs.qsort (tm_alias_pair_cmp);
5816 /* Dump it. */
5817 dump_tm_clone_pairs (tm_alias_pairs);
5819 htab_delete (tm_clone_hash);
5820 tm_clone_hash = NULL;
5821 tm_alias_pairs.release ();
5825 /* Emit an assembler directive to set symbol for DECL visibility to
5826 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
5828 void
5829 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
5830 int vis ATTRIBUTE_UNUSED)
5832 #ifdef HAVE_GAS_HIDDEN
5833 static const char * const visibility_types[] = {
5834 NULL, "protected", "hidden", "internal"
5837 const char *name, *type;
5839 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5840 type = visibility_types[vis];
5842 fprintf (asm_out_file, "\t.%s\t", type);
5843 assemble_name (asm_out_file, name);
5844 fprintf (asm_out_file, "\n");
5845 #else
5846 if (!DECL_ARTIFICIAL (decl))
5847 warning (OPT_Wattributes, "visibility attribute not supported "
5848 "in this configuration; ignored");
5849 #endif
5852 /* A helper function to call assemble_visibility when needed for a decl. */
5855 maybe_assemble_visibility (tree decl)
5857 enum symbol_visibility vis = DECL_VISIBILITY (decl);
5859 if (vis != VISIBILITY_DEFAULT)
5861 targetm.asm_out.assemble_visibility (decl, vis);
5862 return 1;
5864 else
5865 return 0;
5868 /* Returns 1 if the target configuration supports defining public symbols
5869 so that one of them will be chosen at link time instead of generating a
5870 multiply-defined symbol error, whether through the use of weak symbols or
5871 a target-specific mechanism for having duplicates discarded. */
5874 supports_one_only (void)
5876 if (SUPPORTS_ONE_ONLY)
5877 return 1;
5878 return TARGET_SUPPORTS_WEAK;
5881 /* Set up DECL as a public symbol that can be defined in multiple
5882 translation units without generating a linker error. */
5884 void
5885 make_decl_one_only (tree decl, tree comdat_group)
5887 struct symtab_node *symbol;
5888 gcc_assert (TREE_CODE (decl) == VAR_DECL
5889 || TREE_CODE (decl) == FUNCTION_DECL);
5891 TREE_PUBLIC (decl) = 1;
5893 if (TREE_CODE (decl) == VAR_DECL)
5894 symbol = varpool_node::get_create (decl);
5895 else
5896 symbol = cgraph_node::get_create (decl);
5898 if (SUPPORTS_ONE_ONLY)
5900 #ifdef MAKE_DECL_ONE_ONLY
5901 MAKE_DECL_ONE_ONLY (decl);
5902 #endif
5903 symbol->set_comdat_group (comdat_group);
5905 else if (TREE_CODE (decl) == VAR_DECL
5906 && (DECL_INITIAL (decl) == 0
5907 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
5908 DECL_COMMON (decl) = 1;
5909 else
5911 gcc_assert (TARGET_SUPPORTS_WEAK);
5912 DECL_WEAK (decl) = 1;
5916 void
5917 init_varasm_once (void)
5919 section_htab = htab_create_ggc (31, section_entry_hash,
5920 section_entry_eq, NULL);
5921 object_block_htab = htab_create_ggc (31, object_block_entry_hash,
5922 object_block_entry_eq, NULL);
5923 const_desc_htab = htab_create_ggc (1009, const_desc_hash,
5924 const_desc_eq, NULL);
5926 const_alias_set = new_alias_set ();
5927 shared_constant_pool = create_constant_pool ();
5929 #ifdef TEXT_SECTION_ASM_OP
5930 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
5931 TEXT_SECTION_ASM_OP);
5932 #endif
5934 #ifdef DATA_SECTION_ASM_OP
5935 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5936 DATA_SECTION_ASM_OP);
5937 #endif
5939 #ifdef SDATA_SECTION_ASM_OP
5940 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5941 SDATA_SECTION_ASM_OP);
5942 #endif
5944 #ifdef READONLY_DATA_SECTION_ASM_OP
5945 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
5946 READONLY_DATA_SECTION_ASM_OP);
5947 #endif
5949 #ifdef CTORS_SECTION_ASM_OP
5950 ctors_section = get_unnamed_section (0, output_section_asm_op,
5951 CTORS_SECTION_ASM_OP);
5952 #endif
5954 #ifdef DTORS_SECTION_ASM_OP
5955 dtors_section = get_unnamed_section (0, output_section_asm_op,
5956 DTORS_SECTION_ASM_OP);
5957 #endif
5959 #ifdef BSS_SECTION_ASM_OP
5960 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5961 output_section_asm_op,
5962 BSS_SECTION_ASM_OP);
5963 #endif
5965 #ifdef SBSS_SECTION_ASM_OP
5966 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5967 output_section_asm_op,
5968 SBSS_SECTION_ASM_OP);
5969 #endif
5971 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5972 | SECTION_COMMON, emit_tls_common);
5973 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5974 | SECTION_COMMON, emit_local);
5975 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5976 | SECTION_COMMON, emit_common);
5978 #if defined ASM_OUTPUT_ALIGNED_BSS
5979 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
5980 emit_bss);
5981 #endif
5983 targetm.asm_out.init_sections ();
5985 if (readonly_data_section == NULL)
5986 readonly_data_section = text_section;
5988 #ifdef ASM_OUTPUT_EXTERNAL
5989 pending_assemble_externals_set = new hash_set<tree>;
5990 #endif
5993 enum tls_model
5994 decl_default_tls_model (const_tree decl)
5996 enum tls_model kind;
5997 bool is_local;
5999 is_local = targetm.binds_local_p (decl);
6000 if (!flag_shlib)
6002 if (is_local)
6003 kind = TLS_MODEL_LOCAL_EXEC;
6004 else
6005 kind = TLS_MODEL_INITIAL_EXEC;
6008 /* Local dynamic is inefficient when we're not combining the
6009 parts of the address. */
6010 else if (optimize && is_local)
6011 kind = TLS_MODEL_LOCAL_DYNAMIC;
6012 else
6013 kind = TLS_MODEL_GLOBAL_DYNAMIC;
6014 if (kind < flag_tls_default)
6015 kind = flag_tls_default;
6017 return kind;
6020 /* Select a set of attributes for section NAME based on the properties
6021 of DECL and whether or not RELOC indicates that DECL's initializer
6022 might contain runtime relocations.
6024 We make the section read-only and executable for a function decl,
6025 read-only for a const data decl, and writable for a non-const data decl. */
6027 unsigned int
6028 default_section_type_flags (tree decl, const char *name, int reloc)
6030 unsigned int flags;
6032 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6033 flags = SECTION_CODE;
6034 else if (decl)
6036 enum section_category category
6037 = categorize_decl_for_section (decl, reloc);
6038 if (decl_readonly_section_1 (category))
6039 flags = 0;
6040 else if (category == SECCAT_DATA_REL_RO
6041 || category == SECCAT_DATA_REL_RO_LOCAL)
6042 flags = SECTION_WRITE | SECTION_RELRO;
6043 else
6044 flags = SECTION_WRITE;
6046 else
6048 flags = SECTION_WRITE;
6049 if (strcmp (name, ".data.rel.ro") == 0
6050 || strcmp (name, ".data.rel.ro.local") == 0)
6051 flags |= SECTION_RELRO;
6054 if (decl && DECL_P (decl) && DECL_COMDAT_GROUP (decl))
6055 flags |= SECTION_LINKONCE;
6057 if (strcmp (name, ".vtable_map_vars") == 0)
6058 flags |= SECTION_LINKONCE;
6060 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6061 flags |= SECTION_TLS | SECTION_WRITE;
6063 if (strcmp (name, ".bss") == 0
6064 || strncmp (name, ".bss.", 5) == 0
6065 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6066 || strcmp (name, ".sbss") == 0
6067 || strncmp (name, ".sbss.", 6) == 0
6068 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6069 flags |= SECTION_BSS;
6071 if (strcmp (name, ".tdata") == 0
6072 || strncmp (name, ".tdata.", 7) == 0
6073 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6074 flags |= SECTION_TLS;
6076 if (strcmp (name, ".tbss") == 0
6077 || strncmp (name, ".tbss.", 6) == 0
6078 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6079 flags |= SECTION_TLS | SECTION_BSS;
6081 /* These three sections have special ELF types. They are neither
6082 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
6083 want to print a section type (@progbits or @nobits). If someone
6084 is silly enough to emit code or TLS variables to one of these
6085 sections, then don't handle them specially. */
6086 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6087 && (strcmp (name, ".init_array") == 0
6088 || strcmp (name, ".fini_array") == 0
6089 || strcmp (name, ".preinit_array") == 0))
6090 flags |= SECTION_NOTYPE;
6092 return flags;
6095 /* Return true if the target supports some form of global BSS,
6096 either through bss_noswitch_section, or by selecting a BSS
6097 section in TARGET_ASM_SELECT_SECTION. */
6099 bool
6100 have_global_bss_p (void)
6102 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6105 /* Output assembly to switch to section NAME with attribute FLAGS.
6106 Four variants for common object file formats. */
6108 void
6109 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6110 unsigned int flags ATTRIBUTE_UNUSED,
6111 tree decl ATTRIBUTE_UNUSED)
6113 /* Some object formats don't support named sections at all. The
6114 front-end should already have flagged this as an error. */
6115 gcc_unreachable ();
6118 #ifndef TLS_SECTION_ASM_FLAG
6119 #define TLS_SECTION_ASM_FLAG 'T'
6120 #endif
6122 void
6123 default_elf_asm_named_section (const char *name, unsigned int flags,
6124 tree decl ATTRIBUTE_UNUSED)
6126 char flagchars[10], *f = flagchars;
6128 /* If we have already declared this section, we can use an
6129 abbreviated form to switch back to it -- unless this section is
6130 part of a COMDAT groups, in which case GAS requires the full
6131 declaration every time. */
6132 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6133 && (flags & SECTION_DECLARED))
6135 fprintf (asm_out_file, "\t.section\t%s\n", name);
6136 return;
6139 if (!(flags & SECTION_DEBUG))
6140 *f++ = 'a';
6141 if (flags & SECTION_EXCLUDE)
6142 *f++ = 'e';
6143 if (flags & SECTION_WRITE)
6144 *f++ = 'w';
6145 if (flags & SECTION_CODE)
6146 *f++ = 'x';
6147 if (flags & SECTION_SMALL)
6148 *f++ = 's';
6149 if (flags & SECTION_MERGE)
6150 *f++ = 'M';
6151 if (flags & SECTION_STRINGS)
6152 *f++ = 'S';
6153 if (flags & SECTION_TLS)
6154 *f++ = TLS_SECTION_ASM_FLAG;
6155 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6156 *f++ = 'G';
6157 *f = '\0';
6159 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6161 if (!(flags & SECTION_NOTYPE))
6163 const char *type;
6164 const char *format;
6166 if (flags & SECTION_BSS)
6167 type = "nobits";
6168 else
6169 type = "progbits";
6171 format = ",@%s";
6172 /* On platforms that use "@" as the assembly comment character,
6173 use "%" instead. */
6174 if (strcmp (ASM_COMMENT_START, "@") == 0)
6175 format = ",%%%s";
6176 fprintf (asm_out_file, format, type);
6178 if (flags & SECTION_ENTSIZE)
6179 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6180 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6182 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6183 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6184 else
6185 fprintf (asm_out_file, ",%s,comdat",
6186 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6190 putc ('\n', asm_out_file);
6193 void
6194 default_coff_asm_named_section (const char *name, unsigned int flags,
6195 tree decl ATTRIBUTE_UNUSED)
6197 char flagchars[8], *f = flagchars;
6199 if (flags & SECTION_WRITE)
6200 *f++ = 'w';
6201 if (flags & SECTION_CODE)
6202 *f++ = 'x';
6203 *f = '\0';
6205 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6208 void
6209 default_pe_asm_named_section (const char *name, unsigned int flags,
6210 tree decl)
6212 default_coff_asm_named_section (name, flags, decl);
6214 if (flags & SECTION_LINKONCE)
6216 /* Functions may have been compiled at various levels of
6217 optimization so we can't use `same_size' here.
6218 Instead, have the linker pick one. */
6219 fprintf (asm_out_file, "\t.linkonce %s\n",
6220 (flags & SECTION_CODE ? "discard" : "same_size"));
6224 /* The lame default section selector. */
6226 section *
6227 default_select_section (tree decl, int reloc,
6228 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6230 if (DECL_P (decl))
6232 if (decl_readonly_section (decl, reloc))
6233 return readonly_data_section;
6235 else if (TREE_CODE (decl) == CONSTRUCTOR)
6237 if (! ((flag_pic && reloc)
6238 || !TREE_READONLY (decl)
6239 || TREE_SIDE_EFFECTS (decl)
6240 || !TREE_CONSTANT (decl)))
6241 return readonly_data_section;
6243 else if (TREE_CODE (decl) == STRING_CST)
6244 return readonly_data_section;
6245 else if (! (flag_pic && reloc))
6246 return readonly_data_section;
6248 return data_section;
6251 enum section_category
6252 categorize_decl_for_section (const_tree decl, int reloc)
6254 enum section_category ret;
6256 if (TREE_CODE (decl) == FUNCTION_DECL)
6257 return SECCAT_TEXT;
6258 else if (TREE_CODE (decl) == STRING_CST)
6260 if ((flag_sanitize & SANITIZE_ADDRESS)
6261 && asan_protect_global (CONST_CAST_TREE (decl)))
6262 /* or !flag_merge_constants */
6263 return SECCAT_RODATA;
6264 else
6265 return SECCAT_RODATA_MERGE_STR;
6267 else if (TREE_CODE (decl) == VAR_DECL)
6269 if (bss_initializer_p (decl))
6270 ret = SECCAT_BSS;
6271 else if (! TREE_READONLY (decl)
6272 || TREE_SIDE_EFFECTS (decl)
6273 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
6275 /* Here the reloc_rw_mask is not testing whether the section should
6276 be read-only or not, but whether the dynamic link will have to
6277 do something. If so, we wish to segregate the data in order to
6278 minimize cache misses inside the dynamic linker. */
6279 if (reloc & targetm.asm_out.reloc_rw_mask ())
6280 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6281 else
6282 ret = SECCAT_DATA;
6284 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6285 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6286 else if (reloc || flag_merge_constants < 2
6287 || ((flag_sanitize & SANITIZE_ADDRESS)
6288 && asan_protect_global (CONST_CAST_TREE (decl))))
6289 /* C and C++ don't allow different variables to share the same
6290 location. -fmerge-all-constants allows even that (at the
6291 expense of not conforming). */
6292 ret = SECCAT_RODATA;
6293 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6294 ret = SECCAT_RODATA_MERGE_STR_INIT;
6295 else
6296 ret = SECCAT_RODATA_MERGE_CONST;
6298 else if (TREE_CODE (decl) == CONSTRUCTOR)
6300 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6301 || TREE_SIDE_EFFECTS (decl)
6302 || ! TREE_CONSTANT (decl))
6303 ret = SECCAT_DATA;
6304 else
6305 ret = SECCAT_RODATA;
6307 else
6308 ret = SECCAT_RODATA;
6310 /* There are no read-only thread-local sections. */
6311 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6313 /* Note that this would be *just* SECCAT_BSS, except that there's
6314 no concept of a read-only thread-local-data section. */
6315 if (ret == SECCAT_BSS
6316 || (flag_zero_initialized_in_bss
6317 && initializer_zerop (DECL_INITIAL (decl))))
6318 ret = SECCAT_TBSS;
6319 else
6320 ret = SECCAT_TDATA;
6323 /* If the target uses small data sections, select it. */
6324 else if (targetm.in_small_data_p (decl))
6326 if (ret == SECCAT_BSS)
6327 ret = SECCAT_SBSS;
6328 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6329 ret = SECCAT_SRODATA;
6330 else
6331 ret = SECCAT_SDATA;
6334 return ret;
6337 static bool
6338 decl_readonly_section_1 (enum section_category category)
6340 switch (category)
6342 case SECCAT_RODATA:
6343 case SECCAT_RODATA_MERGE_STR:
6344 case SECCAT_RODATA_MERGE_STR_INIT:
6345 case SECCAT_RODATA_MERGE_CONST:
6346 case SECCAT_SRODATA:
6347 return true;
6348 default:
6349 return false;
6353 bool
6354 decl_readonly_section (const_tree decl, int reloc)
6356 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6359 /* Select a section based on the above categorization. */
6361 section *
6362 default_elf_select_section (tree decl, int reloc,
6363 unsigned HOST_WIDE_INT align)
6365 const char *sname;
6366 switch (categorize_decl_for_section (decl, reloc))
6368 case SECCAT_TEXT:
6369 /* We're not supposed to be called on FUNCTION_DECLs. */
6370 gcc_unreachable ();
6371 case SECCAT_RODATA:
6372 return readonly_data_section;
6373 case SECCAT_RODATA_MERGE_STR:
6374 return mergeable_string_section (decl, align, 0);
6375 case SECCAT_RODATA_MERGE_STR_INIT:
6376 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6377 case SECCAT_RODATA_MERGE_CONST:
6378 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6379 case SECCAT_SRODATA:
6380 sname = ".sdata2";
6381 break;
6382 case SECCAT_DATA:
6383 return data_section;
6384 case SECCAT_DATA_REL:
6385 sname = ".data.rel";
6386 break;
6387 case SECCAT_DATA_REL_LOCAL:
6388 sname = ".data.rel.local";
6389 break;
6390 case SECCAT_DATA_REL_RO:
6391 sname = ".data.rel.ro";
6392 break;
6393 case SECCAT_DATA_REL_RO_LOCAL:
6394 sname = ".data.rel.ro.local";
6395 break;
6396 case SECCAT_SDATA:
6397 sname = ".sdata";
6398 break;
6399 case SECCAT_TDATA:
6400 sname = ".tdata";
6401 break;
6402 case SECCAT_BSS:
6403 if (bss_section)
6404 return bss_section;
6405 sname = ".bss";
6406 break;
6407 case SECCAT_SBSS:
6408 sname = ".sbss";
6409 break;
6410 case SECCAT_TBSS:
6411 sname = ".tbss";
6412 break;
6413 default:
6414 gcc_unreachable ();
6417 return get_named_section (decl, sname, reloc);
6420 /* Construct a unique section name based on the decl name and the
6421 categorization performed above. */
6423 void
6424 default_unique_section (tree decl, int reloc)
6426 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6427 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6428 const char *prefix, *name, *linkonce;
6429 char *string;
6431 switch (categorize_decl_for_section (decl, reloc))
6433 case SECCAT_TEXT:
6434 prefix = one_only ? ".t" : ".text";
6435 break;
6436 case SECCAT_RODATA:
6437 case SECCAT_RODATA_MERGE_STR:
6438 case SECCAT_RODATA_MERGE_STR_INIT:
6439 case SECCAT_RODATA_MERGE_CONST:
6440 prefix = one_only ? ".r" : ".rodata";
6441 break;
6442 case SECCAT_SRODATA:
6443 prefix = one_only ? ".s2" : ".sdata2";
6444 break;
6445 case SECCAT_DATA:
6446 prefix = one_only ? ".d" : ".data";
6447 break;
6448 case SECCAT_DATA_REL:
6449 prefix = one_only ? ".d.rel" : ".data.rel";
6450 break;
6451 case SECCAT_DATA_REL_LOCAL:
6452 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6453 break;
6454 case SECCAT_DATA_REL_RO:
6455 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6456 break;
6457 case SECCAT_DATA_REL_RO_LOCAL:
6458 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6459 break;
6460 case SECCAT_SDATA:
6461 prefix = one_only ? ".s" : ".sdata";
6462 break;
6463 case SECCAT_BSS:
6464 prefix = one_only ? ".b" : ".bss";
6465 break;
6466 case SECCAT_SBSS:
6467 prefix = one_only ? ".sb" : ".sbss";
6468 break;
6469 case SECCAT_TDATA:
6470 prefix = one_only ? ".td" : ".tdata";
6471 break;
6472 case SECCAT_TBSS:
6473 prefix = one_only ? ".tb" : ".tbss";
6474 break;
6475 default:
6476 gcc_unreachable ();
6479 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
6480 name = targetm.strip_name_encoding (name);
6482 /* If we're using one_only, then there needs to be a .gnu.linkonce
6483 prefix to the section name. */
6484 linkonce = one_only ? ".gnu.linkonce" : "";
6486 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6488 set_decl_section_name (decl, string);
6491 /* Subroutine of compute_reloc_for_rtx for leaf rtxes. */
6493 static int
6494 compute_reloc_for_rtx_1 (const_rtx x)
6496 switch (GET_CODE (x))
6498 case SYMBOL_REF:
6499 return SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6500 case LABEL_REF:
6501 return 1;
6502 default:
6503 return 0;
6507 /* Like compute_reloc_for_constant, except for an RTX. The return value
6508 is a mask for which bit 1 indicates a global relocation, and bit 0
6509 indicates a local relocation. */
6511 static int
6512 compute_reloc_for_rtx (const_rtx x)
6514 switch (GET_CODE (x))
6516 case SYMBOL_REF:
6517 case LABEL_REF:
6518 return compute_reloc_for_rtx_1 (x);
6520 case CONST:
6522 int reloc = 0;
6523 subrtx_iterator::array_type array;
6524 FOR_EACH_SUBRTX (iter, array, x, ALL)
6525 reloc |= compute_reloc_for_rtx_1 (*iter);
6526 return reloc;
6529 default:
6530 return 0;
6534 section *
6535 default_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
6536 rtx x,
6537 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6539 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6540 return data_section;
6541 else
6542 return readonly_data_section;
6545 section *
6546 default_elf_select_rtx_section (enum machine_mode mode, rtx x,
6547 unsigned HOST_WIDE_INT align)
6549 int reloc = compute_reloc_for_rtx (x);
6551 /* ??? Handle small data here somehow. */
6553 if (reloc & targetm.asm_out.reloc_rw_mask ())
6555 if (reloc == 1)
6556 return get_named_section (NULL, ".data.rel.ro.local", 1);
6557 else
6558 return get_named_section (NULL, ".data.rel.ro", 3);
6561 return mergeable_constant_section (mode, align, 0);
6564 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6566 void
6567 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6569 rtx symbol;
6570 int flags;
6572 /* Careful not to prod global register variables. */
6573 if (!MEM_P (rtl))
6574 return;
6575 symbol = XEXP (rtl, 0);
6576 if (GET_CODE (symbol) != SYMBOL_REF)
6577 return;
6579 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6580 if (TREE_CODE (decl) == FUNCTION_DECL)
6581 flags |= SYMBOL_FLAG_FUNCTION;
6582 if (targetm.binds_local_p (decl))
6583 flags |= SYMBOL_FLAG_LOCAL;
6584 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6585 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6586 else if (targetm.in_small_data_p (decl))
6587 flags |= SYMBOL_FLAG_SMALL;
6588 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6589 being PUBLIC, the thing *must* be defined in this translation unit.
6590 Prevent this buglet from being propagated into rtl code as well. */
6591 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6592 flags |= SYMBOL_FLAG_EXTERNAL;
6594 SYMBOL_REF_FLAGS (symbol) = flags;
6597 /* By default, we do nothing for encode_section_info, so we need not
6598 do anything but discard the '*' marker. */
6600 const char *
6601 default_strip_name_encoding (const char *str)
6603 return str + (*str == '*');
6606 #ifdef ASM_OUTPUT_DEF
6607 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6608 anchor relative to ".", the current section position. */
6610 void
6611 default_asm_output_anchor (rtx symbol)
6613 char buffer[100];
6615 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6616 SYMBOL_REF_BLOCK_OFFSET (symbol));
6617 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6619 #endif
6621 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6623 bool
6624 default_use_anchors_for_symbol_p (const_rtx symbol)
6626 section *sect;
6627 tree decl;
6629 /* Don't use anchors for mergeable sections. The linker might move
6630 the objects around. */
6631 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6632 if (sect->common.flags & SECTION_MERGE)
6633 return false;
6635 /* Don't use anchors for small data sections. The small data register
6636 acts as an anchor for such sections. */
6637 if (sect->common.flags & SECTION_SMALL)
6638 return false;
6640 decl = SYMBOL_REF_DECL (symbol);
6641 if (decl && DECL_P (decl))
6643 /* Don't use section anchors for decls that might be defined or
6644 usurped by other modules. */
6645 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6646 return false;
6648 /* Don't use section anchors for decls that will be placed in a
6649 small data section. */
6650 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6651 one above. The problem is that we only use SECTION_SMALL for
6652 sections that should be marked as small in the section directive. */
6653 if (targetm.in_small_data_p (decl))
6654 return false;
6656 return true;
6659 /* Return true when RESOLUTION indicate that symbol will be bound to the
6660 definition provided by current .o file. */
6662 static bool
6663 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
6665 return (resolution == LDPR_PREVAILING_DEF
6666 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6667 || resolution == LDPR_PREVAILING_DEF_IRONLY);
6670 /* Return true when RESOLUTION indicate that symbol will be bound locally
6671 within current executable or DSO. */
6673 static bool
6674 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
6676 return (resolution == LDPR_PREVAILING_DEF
6677 || resolution == LDPR_PREVAILING_DEF_IRONLY
6678 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6679 || resolution == LDPR_PREEMPTED_REG
6680 || resolution == LDPR_PREEMPTED_IR
6681 || resolution == LDPR_RESOLVED_IR
6682 || resolution == LDPR_RESOLVED_EXEC);
6685 /* Assume ELF-ish defaults, since that's pretty much the most liberal
6686 wrt cross-module name binding. */
6688 bool
6689 default_binds_local_p (const_tree exp)
6691 return default_binds_local_p_1 (exp, flag_shlib);
6694 bool
6695 default_binds_local_p_1 (const_tree exp, int shlib)
6697 bool local_p;
6698 bool resolved_locally = false;
6699 bool resolved_to_local_def = false;
6701 /* With resolution file in hands, take look into resolutions.
6702 We can't just return true for resolved_locally symbols,
6703 because dynamic linking might overwrite symbols
6704 in shared libraries. */
6705 if (TREE_CODE (exp) == VAR_DECL && TREE_PUBLIC (exp)
6706 && (TREE_STATIC (exp) || DECL_EXTERNAL (exp)))
6708 varpool_node *vnode = varpool_node::get (exp);
6709 if (vnode && (resolution_local_p (vnode->resolution) || vnode->in_other_partition))
6710 resolved_locally = true;
6711 if (vnode
6712 && resolution_to_local_definition_p (vnode->resolution))
6713 resolved_to_local_def = true;
6715 else if (TREE_CODE (exp) == FUNCTION_DECL && TREE_PUBLIC (exp))
6717 struct cgraph_node *node = cgraph_node::get (exp);
6718 if (node
6719 && (resolution_local_p (node->resolution) || node->in_other_partition))
6720 resolved_locally = true;
6721 if (node
6722 && resolution_to_local_definition_p (node->resolution))
6723 resolved_to_local_def = true;
6726 /* A non-decl is an entry in the constant pool. */
6727 if (!DECL_P (exp))
6728 local_p = true;
6729 /* Weakrefs may not bind locally, even though the weakref itself is always
6730 static and therefore local. Similarly, the resolver for ifunc functions
6731 might resolve to a non-local function.
6732 FIXME: We can resolve the weakref case more curefuly by looking at the
6733 weakref alias. */
6734 else if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
6735 || (TREE_CODE (exp) == FUNCTION_DECL
6736 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
6737 local_p = false;
6738 /* Static variables are always local. */
6739 else if (! TREE_PUBLIC (exp))
6740 local_p = true;
6741 /* A variable is local if the user has said explicitly that it will
6742 be. */
6743 else if ((DECL_VISIBILITY_SPECIFIED (exp)
6744 || resolved_to_local_def)
6745 && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6746 local_p = true;
6747 /* Variables defined outside this object might not be local. */
6748 else if (DECL_EXTERNAL (exp) && !resolved_locally)
6749 local_p = false;
6750 /* If defined in this object and visibility is not default, must be
6751 local. */
6752 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6753 local_p = true;
6754 /* Default visibility weak data can be overridden by a strong symbol
6755 in another module and so are not local. */
6756 else if (DECL_WEAK (exp)
6757 && !resolved_locally)
6758 local_p = false;
6759 /* If PIC, then assume that any global name can be overridden by
6760 symbols resolved from other modules. */
6761 else if (shlib)
6762 local_p = false;
6763 /* Uninitialized COMMON variable may be unified with symbols
6764 resolved from other modules. */
6765 else if (DECL_COMMON (exp)
6766 && !resolved_locally
6767 && (DECL_INITIAL (exp) == NULL
6768 || (!in_lto_p && DECL_INITIAL (exp) == error_mark_node)))
6769 local_p = false;
6770 /* Otherwise we're left with initialized (or non-common) global data
6771 which is of necessity defined locally. */
6772 else
6773 local_p = true;
6775 return local_p;
6778 /* Return true when references to DECL must bind to current definition in
6779 final executable.
6781 The condition is usually equivalent to whether the function binds to the
6782 current module (shared library or executable), that is to binds_local_p.
6783 We use this fact to avoid need for another target hook and implement
6784 the logic using binds_local_p and just special cases where
6785 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
6786 the weak definitions (that can be overwritten at linktime by other
6787 definition from different object file) and when resolution info is available
6788 we simply use the knowledge passed to us by linker plugin. */
6789 bool
6790 decl_binds_to_current_def_p (const_tree decl)
6792 gcc_assert (DECL_P (decl));
6793 if (!targetm.binds_local_p (decl))
6794 return false;
6795 if (!TREE_PUBLIC (decl))
6796 return true;
6797 /* When resolution is available, just use it. */
6798 if (TREE_CODE (decl) == VAR_DECL
6799 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl)))
6801 varpool_node *vnode = varpool_node::get (decl);
6802 if (vnode
6803 && vnode->resolution != LDPR_UNKNOWN)
6804 return resolution_to_local_definition_p (vnode->resolution);
6806 else if (TREE_CODE (decl) == FUNCTION_DECL)
6808 struct cgraph_node *node = cgraph_node::get (decl);
6809 if (node
6810 && node->resolution != LDPR_UNKNOWN)
6811 return resolution_to_local_definition_p (node->resolution);
6813 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
6814 binds locally but still can be overwritten), DECL_COMMON (can be merged
6815 with a non-common definition somewhere in the same module) or
6816 DECL_EXTERNAL.
6817 This rely on fact that binds_local_p behave as decl_replaceable_p
6818 for all other declaration types. */
6819 if (DECL_WEAK (decl))
6820 return false;
6821 if (DECL_COMMON (decl)
6822 && (DECL_INITIAL (decl) == NULL
6823 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
6824 return false;
6825 if (DECL_EXTERNAL (decl))
6826 return false;
6827 return true;
6830 /* A replaceable function or variable is one which may be replaced
6831 at link-time with an entirely different definition, provided that the
6832 replacement has the same type. For example, functions declared
6833 with __attribute__((weak)) on most systems are replaceable.
6835 COMDAT functions are not replaceable, since all definitions of the
6836 function must be equivalent. It is important that COMDAT functions
6837 not be treated as replaceable so that use of C++ template
6838 instantiations is not penalized. */
6840 bool
6841 decl_replaceable_p (tree decl)
6843 gcc_assert (DECL_P (decl));
6844 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
6845 return false;
6846 if (!flag_semantic_interposition
6847 && !DECL_WEAK (decl))
6848 return false;
6849 return !decl_binds_to_current_def_p (decl);
6852 /* Default function to output code that will globalize a label. A
6853 target must define GLOBAL_ASM_OP or provide its own function to
6854 globalize a label. */
6855 #ifdef GLOBAL_ASM_OP
6856 void
6857 default_globalize_label (FILE * stream, const char *name)
6859 fputs (GLOBAL_ASM_OP, stream);
6860 assemble_name (stream, name);
6861 putc ('\n', stream);
6863 #endif /* GLOBAL_ASM_OP */
6865 /* Default function to output code that will globalize a declaration. */
6866 void
6867 default_globalize_decl_name (FILE * stream, tree decl)
6869 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
6870 targetm.asm_out.globalize_label (stream, name);
6873 /* Default function to output a label for unwind information. The
6874 default is to do nothing. A target that needs nonlocal labels for
6875 unwind information must provide its own function to do this. */
6876 void
6877 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
6878 tree decl ATTRIBUTE_UNUSED,
6879 int for_eh ATTRIBUTE_UNUSED,
6880 int empty ATTRIBUTE_UNUSED)
6884 /* Default function to output a label to divide up the exception table.
6885 The default is to do nothing. A target that needs/wants to divide
6886 up the table must provide it's own function to do this. */
6887 void
6888 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
6892 /* This is how to output an internal numbered label where PREFIX is
6893 the class of label and LABELNO is the number within the class. */
6895 void
6896 default_generate_internal_label (char *buf, const char *prefix,
6897 unsigned long labelno)
6899 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6902 /* This is how to output an internal numbered label where PREFIX is
6903 the class of label and LABELNO is the number within the class. */
6905 void
6906 default_internal_label (FILE *stream, const char *prefix,
6907 unsigned long labelno)
6909 char *const buf = (char *) alloca (40 + strlen (prefix));
6910 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6911 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
6915 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
6917 void
6918 default_asm_declare_constant_name (FILE *file, const char *name,
6919 const_tree exp ATTRIBUTE_UNUSED,
6920 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
6922 assemble_label (file, name);
6925 /* This is the default behavior at the beginning of a file. It's
6926 controlled by two other target-hook toggles. */
6927 void
6928 default_file_start (void)
6930 if (targetm.asm_file_start_app_off
6931 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
6932 fputs (ASM_APP_OFF, asm_out_file);
6934 if (targetm.asm_file_start_file_directive)
6935 output_file_directive (asm_out_file, main_input_filename);
6938 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
6939 which emits a special section directive used to indicate whether or
6940 not this object file needs an executable stack. This is primarily
6941 a GNU extension to ELF but could be used on other targets. */
6943 int trampolines_created;
6945 void
6946 file_end_indicate_exec_stack (void)
6948 unsigned int flags = SECTION_DEBUG;
6949 if (trampolines_created)
6950 flags |= SECTION_CODE;
6952 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
6955 /* Emit a special section directive to indicate that this object file
6956 was compiled with -fsplit-stack. This is used to let the linker
6957 detect calls between split-stack code and non-split-stack code, so
6958 that it can modify the split-stack code to allocate a sufficiently
6959 large stack. We emit another special section if there are any
6960 functions in this file which have the no_split_stack attribute, to
6961 prevent the linker from warning about being unable to convert the
6962 functions if they call non-split-stack code. */
6964 void
6965 file_end_indicate_split_stack (void)
6967 if (flag_split_stack)
6969 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
6970 NULL));
6971 if (saw_no_split_stack)
6972 switch_to_section (get_section (".note.GNU-no-split-stack",
6973 SECTION_DEBUG, NULL));
6977 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
6978 a get_unnamed_section callback. */
6980 void
6981 output_section_asm_op (const void *directive)
6983 fprintf (asm_out_file, "%s\n", (const char *) directive);
6986 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
6987 the current section is NEW_SECTION. */
6989 void
6990 switch_to_section (section *new_section)
6992 if (in_section == new_section)
6993 return;
6995 if (new_section->common.flags & SECTION_FORGET)
6996 in_section = NULL;
6997 else
6998 in_section = new_section;
7000 switch (SECTION_STYLE (new_section))
7002 case SECTION_NAMED:
7003 targetm.asm_out.named_section (new_section->named.name,
7004 new_section->named.common.flags,
7005 new_section->named.decl);
7006 break;
7008 case SECTION_UNNAMED:
7009 new_section->unnamed.callback (new_section->unnamed.data);
7010 break;
7012 case SECTION_NOSWITCH:
7013 gcc_unreachable ();
7014 break;
7017 new_section->common.flags |= SECTION_DECLARED;
7020 /* If block symbol SYMBOL has not yet been assigned an offset, place
7021 it at the end of its block. */
7023 void
7024 place_block_symbol (rtx symbol)
7026 unsigned HOST_WIDE_INT size, mask, offset;
7027 struct constant_descriptor_rtx *desc;
7028 unsigned int alignment;
7029 struct object_block *block;
7030 tree decl;
7032 gcc_assert (SYMBOL_REF_BLOCK (symbol));
7033 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7034 return;
7036 /* Work out the symbol's size and alignment. */
7037 if (CONSTANT_POOL_ADDRESS_P (symbol))
7039 desc = SYMBOL_REF_CONSTANT (symbol);
7040 alignment = desc->align;
7041 size = GET_MODE_SIZE (desc->mode);
7043 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7045 decl = SYMBOL_REF_DECL (symbol);
7046 alignment = DECL_ALIGN (decl);
7047 size = get_constant_size (DECL_INITIAL (decl));
7048 if ((flag_sanitize & SANITIZE_ADDRESS)
7049 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7050 && asan_protect_global (DECL_INITIAL (decl)))
7051 size += asan_red_zone_size (size);
7053 else
7055 struct symtab_node *snode;
7056 decl = SYMBOL_REF_DECL (symbol);
7058 snode = symtab_node::get (decl);
7059 if (snode->alias)
7061 rtx target = DECL_RTL (snode->ultimate_alias_target ()->decl);
7063 place_block_symbol (target);
7064 SYMBOL_REF_BLOCK_OFFSET (symbol) = SYMBOL_REF_BLOCK_OFFSET (target);
7065 return;
7067 alignment = get_variable_align (decl);
7068 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7069 if ((flag_sanitize & SANITIZE_ADDRESS)
7070 && asan_protect_global (decl))
7072 size += asan_red_zone_size (size);
7073 alignment = MAX (alignment,
7074 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7078 /* Calculate the object's offset from the start of the block. */
7079 block = SYMBOL_REF_BLOCK (symbol);
7080 mask = alignment / BITS_PER_UNIT - 1;
7081 offset = (block->size + mask) & ~mask;
7082 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7084 /* Record the block's new alignment and size. */
7085 block->alignment = MAX (block->alignment, alignment);
7086 block->size = offset + size;
7088 vec_safe_push (block->objects, symbol);
7091 /* Return the anchor that should be used to address byte offset OFFSET
7092 from the first object in BLOCK. MODEL is the TLS model used
7093 to access it. */
7096 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7097 enum tls_model model)
7099 char label[100];
7100 unsigned int begin, middle, end;
7101 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7102 rtx anchor;
7104 /* Work out the anchor's offset. Use an offset of 0 for the first
7105 anchor so that we don't pessimize the case where we take the address
7106 of a variable at the beginning of the block. This is particularly
7107 useful when a block has only one variable assigned to it.
7109 We try to place anchors RANGE bytes apart, so there can then be
7110 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7111 a ptr_mode offset. With some target settings, the lowest such
7112 anchor might be out of range for the lowest ptr_mode offset;
7113 likewise the highest anchor for the highest offset. Use anchors
7114 at the extreme ends of the ptr_mode range in such cases.
7116 All arithmetic uses unsigned integers in order to avoid
7117 signed overflow. */
7118 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7119 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7120 range = max_offset - min_offset + 1;
7121 if (range == 0)
7122 offset = 0;
7123 else
7125 bias = 1 << (GET_MODE_BITSIZE (ptr_mode) - 1);
7126 if (offset < 0)
7128 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7129 delta -= delta % range;
7130 if (delta > bias)
7131 delta = bias;
7132 offset = (HOST_WIDE_INT) (-delta);
7134 else
7136 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7137 delta -= delta % range;
7138 if (delta > bias - 1)
7139 delta = bias - 1;
7140 offset = (HOST_WIDE_INT) delta;
7144 /* Do a binary search to see if there's already an anchor we can use.
7145 Set BEGIN to the new anchor's index if not. */
7146 begin = 0;
7147 end = vec_safe_length (block->anchors);
7148 while (begin != end)
7150 middle = (end + begin) / 2;
7151 anchor = (*block->anchors)[middle];
7152 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7153 end = middle;
7154 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7155 begin = middle + 1;
7156 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7157 end = middle;
7158 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7159 begin = middle + 1;
7160 else
7161 return anchor;
7164 /* Create a new anchor with a unique label. */
7165 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7166 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7167 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7168 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7170 /* Insert it at index BEGIN. */
7171 vec_safe_insert (block->anchors, begin, anchor);
7172 return anchor;
7175 /* Output the objects in BLOCK. */
7177 static void
7178 output_object_block (struct object_block *block)
7180 struct constant_descriptor_rtx *desc;
7181 unsigned int i;
7182 HOST_WIDE_INT offset;
7183 tree decl;
7184 rtx symbol;
7186 if (!block->objects)
7187 return;
7189 /* Switch to the section and make sure that the first byte is
7190 suitably aligned. */
7191 switch_to_section (block->sect);
7192 assemble_align (block->alignment);
7194 /* Define the values of all anchors relative to the current section
7195 position. */
7196 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7197 targetm.asm_out.output_anchor (symbol);
7199 /* Output the objects themselves. */
7200 offset = 0;
7201 FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7203 /* Move to the object's offset, padding with zeros if necessary. */
7204 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7205 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7206 if (CONSTANT_POOL_ADDRESS_P (symbol))
7208 desc = SYMBOL_REF_CONSTANT (symbol);
7209 output_constant_pool_1 (desc, 1);
7210 offset += GET_MODE_SIZE (desc->mode);
7212 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7214 HOST_WIDE_INT size;
7215 decl = SYMBOL_REF_DECL (symbol);
7216 assemble_constant_contents (DECL_INITIAL (decl), XSTR (symbol, 0),
7217 DECL_ALIGN (decl));
7218 size = get_constant_size (DECL_INITIAL (decl));
7219 offset += size;
7220 if ((flag_sanitize & SANITIZE_ADDRESS)
7221 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7222 && asan_protect_global (DECL_INITIAL (decl)))
7224 size = asan_red_zone_size (size);
7225 assemble_zeros (size);
7226 offset += size;
7229 else
7231 HOST_WIDE_INT size;
7232 decl = SYMBOL_REF_DECL (symbol);
7233 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7234 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7235 offset += size;
7236 if ((flag_sanitize & SANITIZE_ADDRESS)
7237 && asan_protect_global (decl))
7239 size = asan_red_zone_size (size);
7240 assemble_zeros (size);
7241 offset += size;
7247 /* A htab_traverse callback used to call output_object_block for
7248 each member of object_block_htab. */
7250 static int
7251 output_object_block_htab (void **slot, void *data ATTRIBUTE_UNUSED)
7253 output_object_block ((struct object_block *) (*slot));
7254 return 1;
7257 /* Output the definitions of all object_blocks. */
7259 void
7260 output_object_blocks (void)
7262 htab_traverse (object_block_htab, output_object_block_htab, NULL);
7265 /* This function provides a possible implementation of the
7266 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7267 by -frecord-gcc-switches it creates a new mergeable, string section in the
7268 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7269 contains the switches in ASCII format.
7271 FIXME: This code does not correctly handle double quote characters
7272 that appear inside strings, (it strips them rather than preserving them).
7273 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7274 characters - instead it treats them as sub-string separators. Since
7275 we want to emit NUL strings terminators into the object file we have to use
7276 ASM_OUTPUT_SKIP. */
7279 elf_record_gcc_switches (print_switch_type type, const char * name)
7281 switch (type)
7283 case SWITCH_TYPE_PASSED:
7284 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7285 ASM_OUTPUT_SKIP (asm_out_file, (unsigned HOST_WIDE_INT) 1);
7286 break;
7288 case SWITCH_TYPE_DESCRIPTIVE:
7289 if (name == NULL)
7291 /* Distinguish between invocations where name is NULL. */
7292 static bool started = false;
7294 if (!started)
7296 section * sec;
7298 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7299 SECTION_DEBUG
7300 | SECTION_MERGE
7301 | SECTION_STRINGS
7302 | (SECTION_ENTSIZE & 1),
7303 NULL);
7304 switch_to_section (sec);
7305 started = true;
7309 default:
7310 break;
7313 /* The return value is currently ignored by the caller, but must be 0.
7314 For -fverbose-asm the return value would be the number of characters
7315 emitted into the assembler file. */
7316 return 0;
7319 /* Emit text to declare externally defined symbols. It is needed to
7320 properly support non-default visibility. */
7321 void
7322 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7323 tree decl,
7324 const char *name ATTRIBUTE_UNUSED)
7326 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7327 set in order to avoid putting out names that are never really
7328 used. */
7329 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7330 && targetm.binds_local_p (decl))
7331 maybe_assemble_visibility (decl);
7334 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7336 void
7337 default_asm_output_source_filename (FILE *file, const char *name)
7339 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7340 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7341 #else
7342 fprintf (file, "\t.file\t");
7343 output_quoted_string (file, name);
7344 putc ('\n', file);
7345 #endif
7348 /* Output a file name in the form wanted by System V. */
7350 void
7351 output_file_directive (FILE *asm_file, const char *input_name)
7353 int len;
7354 const char *na;
7356 if (input_name == NULL)
7357 input_name = "<stdin>";
7358 else
7359 input_name = remap_debug_filename (input_name);
7361 len = strlen (input_name);
7362 na = input_name + len;
7364 /* NA gets INPUT_NAME sans directory names. */
7365 while (na > input_name)
7367 if (IS_DIR_SEPARATOR (na[-1]))
7368 break;
7369 na--;
7372 targetm.asm_out.output_source_filename (asm_file, na);
7375 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7376 EXP. */
7378 make_debug_expr_from_rtl (const_rtx exp)
7380 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7381 enum machine_mode mode = GET_MODE (exp);
7382 rtx dval;
7384 DECL_ARTIFICIAL (ddecl) = 1;
7385 if (REG_P (exp) && REG_EXPR (exp))
7386 type = TREE_TYPE (REG_EXPR (exp));
7387 else if (MEM_P (exp) && MEM_EXPR (exp))
7388 type = TREE_TYPE (MEM_EXPR (exp));
7389 else
7390 type = NULL_TREE;
7391 if (type && TYPE_MODE (type) == mode)
7392 TREE_TYPE (ddecl) = type;
7393 else
7394 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7395 DECL_MODE (ddecl) = mode;
7396 dval = gen_rtx_DEBUG_EXPR (mode);
7397 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7398 SET_DECL_RTL (ddecl, dval);
7399 return dval;
7402 #ifdef ELF_ASCII_ESCAPES
7403 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7405 void
7406 default_elf_asm_output_limited_string (FILE *f, const char *s)
7408 int escape;
7409 unsigned char c;
7411 fputs (STRING_ASM_OP, f);
7412 putc ('"', f);
7413 while (*s != '\0')
7415 c = *s;
7416 escape = ELF_ASCII_ESCAPES[c];
7417 switch (escape)
7419 case 0:
7420 putc (c, f);
7421 break;
7422 case 1:
7423 /* TODO: Print in hex with fast function, important for -flto. */
7424 fprintf (f, "\\%03o", c);
7425 break;
7426 default:
7427 putc ('\\', f);
7428 putc (escape, f);
7429 break;
7431 s++;
7433 putc ('\"', f);
7434 putc ('\n', f);
7437 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7439 void
7440 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7442 const char *limit = s + len;
7443 const char *last_null = NULL;
7444 unsigned bytes_in_chunk = 0;
7445 unsigned char c;
7446 int escape;
7448 for (; s < limit; s++)
7450 const char *p;
7452 if (bytes_in_chunk >= 60)
7454 putc ('\"', f);
7455 putc ('\n', f);
7456 bytes_in_chunk = 0;
7459 if (s > last_null)
7461 for (p = s; p < limit && *p != '\0'; p++)
7462 continue;
7463 last_null = p;
7465 else
7466 p = last_null;
7468 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7470 if (bytes_in_chunk > 0)
7472 putc ('\"', f);
7473 putc ('\n', f);
7474 bytes_in_chunk = 0;
7477 default_elf_asm_output_limited_string (f, s);
7478 s = p;
7480 else
7482 if (bytes_in_chunk == 0)
7483 fputs (ASCII_DATA_ASM_OP "\"", f);
7485 c = *s;
7486 escape = ELF_ASCII_ESCAPES[c];
7487 switch (escape)
7489 case 0:
7490 putc (c, f);
7491 bytes_in_chunk++;
7492 break;
7493 case 1:
7494 /* TODO: Print in hex with fast function, important for -flto. */
7495 fprintf (f, "\\%03o", c);
7496 bytes_in_chunk += 4;
7497 break;
7498 default:
7499 putc ('\\', f);
7500 putc (escape, f);
7501 bytes_in_chunk += 2;
7502 break;
7508 if (bytes_in_chunk > 0)
7510 putc ('\"', f);
7511 putc ('\n', f);
7514 #endif
7516 static GTY(()) section *elf_init_array_section;
7517 static GTY(()) section *elf_fini_array_section;
7519 static section *
7520 get_elf_initfini_array_priority_section (int priority,
7521 bool constructor_p)
7523 section *sec;
7524 if (priority != DEFAULT_INIT_PRIORITY)
7526 char buf[18];
7527 sprintf (buf, "%s.%.5u",
7528 constructor_p ? ".init_array" : ".fini_array",
7529 priority);
7530 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7532 else
7534 if (constructor_p)
7536 if (elf_init_array_section == NULL)
7537 elf_init_array_section
7538 = get_section (".init_array",
7539 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7540 sec = elf_init_array_section;
7542 else
7544 if (elf_fini_array_section == NULL)
7545 elf_fini_array_section
7546 = get_section (".fini_array",
7547 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7548 sec = elf_fini_array_section;
7551 return sec;
7554 /* Use .init_array section for constructors. */
7556 void
7557 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7559 section *sec = get_elf_initfini_array_priority_section (priority,
7560 true);
7561 assemble_addr_to_section (symbol, sec);
7564 /* Use .fini_array section for destructors. */
7566 void
7567 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7569 section *sec = get_elf_initfini_array_priority_section (priority,
7570 false);
7571 assemble_addr_to_section (symbol, sec);
7574 /* Default TARGET_ASM_OUTPUT_IDENT hook.
7576 This is a bit of a cheat. The real default is a no-op, but this
7577 hook is the default for all targets with a .ident directive. */
7579 void
7580 default_asm_output_ident_directive (const char *ident_str)
7582 const char *ident_asm_op = "\t.ident\t";
7584 /* If we are still in the front end, do not write out the string
7585 to asm_out_file. Instead, add a fake top-level asm statement.
7586 This allows the front ends to use this hook without actually
7587 writing to asm_out_file, to handle #ident or Pragma Ident. */
7588 if (symtab->state == PARSING)
7590 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
7591 symtab->finalize_toplevel_asm (build_string (strlen (buf), buf));
7593 else
7594 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
7597 #include "gt-varasm.h"