Merge trunk version 214779 into gupc branch.
[official-gcc.git] / gcc / varasm.c
blobfe714fe4514ba16e9475e4cffd0dd80bcae8414d
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 + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13;
2926 break;
2928 default:
2929 gcc_unreachable ();
2932 return hi;
2934 case PLUS_EXPR:
2935 case POINTER_PLUS_EXPR:
2936 case MINUS_EXPR:
2937 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2938 + const_hash_1 (TREE_OPERAND (exp, 1)));
2940 CASE_CONVERT:
2941 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
2943 default:
2944 /* A language specific constant. Just hash the code. */
2945 return code;
2948 /* Compute hashing function. */
2949 hi = len;
2950 for (i = 0; i < len; i++)
2951 hi = ((hi * 613) + (unsigned) (p[i]));
2953 return hi;
2956 /* Wrapper of compare_constant, for the htab interface. */
2957 static int
2958 const_desc_eq (const void *p1, const void *p2)
2960 const struct constant_descriptor_tree *const c1
2961 = (const struct constant_descriptor_tree *) p1;
2962 const struct constant_descriptor_tree *const c2
2963 = (const struct constant_descriptor_tree *) p2;
2964 if (c1->hash != c2->hash)
2965 return 0;
2966 return compare_constant (c1->value, c2->value);
2969 /* Compare t1 and t2, and return 1 only if they are known to result in
2970 the same bit pattern on output. */
2972 static int
2973 compare_constant (const tree t1, const tree t2)
2975 enum tree_code typecode;
2977 if (t1 == NULL_TREE)
2978 return t2 == NULL_TREE;
2979 if (t2 == NULL_TREE)
2980 return 0;
2982 if (TREE_CODE (t1) != TREE_CODE (t2))
2983 return 0;
2985 switch (TREE_CODE (t1))
2987 case INTEGER_CST:
2988 /* Integer constants are the same only if the same width of type. */
2989 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2990 return 0;
2991 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2992 return 0;
2993 return tree_int_cst_equal (t1, t2);
2995 case REAL_CST:
2996 /* Real constants are the same only if the same width of type. */
2997 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2998 return 0;
3000 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
3002 case FIXED_CST:
3003 /* Fixed constants are the same only if the same width of type. */
3004 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3005 return 0;
3007 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
3009 case STRING_CST:
3010 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3011 return 0;
3013 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
3014 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
3015 TREE_STRING_LENGTH (t1)));
3017 case COMPLEX_CST:
3018 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
3019 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
3021 case VECTOR_CST:
3023 unsigned i;
3025 if (VECTOR_CST_NELTS (t1) != VECTOR_CST_NELTS (t2))
3026 return 0;
3028 for (i = 0; i < VECTOR_CST_NELTS (t1); ++i)
3029 if (!compare_constant (VECTOR_CST_ELT (t1, i),
3030 VECTOR_CST_ELT (t2, i)))
3031 return 0;
3033 return 1;
3036 case CONSTRUCTOR:
3038 vec<constructor_elt, va_gc> *v1, *v2;
3039 unsigned HOST_WIDE_INT idx;
3041 typecode = TREE_CODE (TREE_TYPE (t1));
3042 if (typecode != TREE_CODE (TREE_TYPE (t2)))
3043 return 0;
3045 if (typecode == ARRAY_TYPE)
3047 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
3048 /* For arrays, check that the sizes all match. */
3049 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
3050 || size_1 == -1
3051 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
3052 return 0;
3054 else
3056 /* For record and union constructors, require exact type
3057 equality. */
3058 if (TREE_TYPE (t1) != TREE_TYPE (t2))
3059 return 0;
3062 v1 = CONSTRUCTOR_ELTS (t1);
3063 v2 = CONSTRUCTOR_ELTS (t2);
3064 if (vec_safe_length (v1) != vec_safe_length (v2))
3065 return 0;
3067 for (idx = 0; idx < vec_safe_length (v1); ++idx)
3069 constructor_elt *c1 = &(*v1)[idx];
3070 constructor_elt *c2 = &(*v2)[idx];
3072 /* Check that each value is the same... */
3073 if (!compare_constant (c1->value, c2->value))
3074 return 0;
3075 /* ... and that they apply to the same fields! */
3076 if (typecode == ARRAY_TYPE)
3078 if (!compare_constant (c1->index, c2->index))
3079 return 0;
3081 else
3083 if (c1->index != c2->index)
3084 return 0;
3088 return 1;
3091 case ADDR_EXPR:
3092 case FDESC_EXPR:
3094 struct addr_const value1, value2;
3095 enum rtx_code code;
3096 int ret;
3098 decode_addr_const (t1, &value1);
3099 decode_addr_const (t2, &value2);
3101 if (value1.offset != value2.offset)
3102 return 0;
3104 code = GET_CODE (value1.base);
3105 if (code != GET_CODE (value2.base))
3106 return 0;
3108 switch (code)
3110 case SYMBOL_REF:
3111 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3112 break;
3114 case LABEL_REF:
3115 ret = (CODE_LABEL_NUMBER (XEXP (value1.base, 0))
3116 == CODE_LABEL_NUMBER (XEXP (value2.base, 0)));
3117 break;
3119 default:
3120 gcc_unreachable ();
3122 return ret;
3125 case PLUS_EXPR:
3126 case POINTER_PLUS_EXPR:
3127 case MINUS_EXPR:
3128 case RANGE_EXPR:
3129 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3130 && compare_constant (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3132 CASE_CONVERT:
3133 case VIEW_CONVERT_EXPR:
3134 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3136 default:
3137 return 0;
3140 gcc_unreachable ();
3143 /* Return the section into which constant EXP should be placed. */
3145 static section *
3146 get_constant_section (tree exp, unsigned int align)
3148 return targetm.asm_out.select_section (exp,
3149 compute_reloc_for_constant (exp),
3150 align);
3153 /* Return the size of constant EXP in bytes. */
3155 static HOST_WIDE_INT
3156 get_constant_size (tree exp)
3158 HOST_WIDE_INT size;
3160 size = int_size_in_bytes (TREE_TYPE (exp));
3161 if (TREE_CODE (exp) == STRING_CST)
3162 size = MAX (TREE_STRING_LENGTH (exp), size);
3163 return size;
3166 /* Subroutine of output_constant_def:
3167 No constant equal to EXP is known to have been output.
3168 Make a constant descriptor to enter EXP in the hash table.
3169 Assign the label number and construct RTL to refer to the
3170 constant's location in memory.
3171 Caller is responsible for updating the hash table. */
3173 static struct constant_descriptor_tree *
3174 build_constant_desc (tree exp)
3176 struct constant_descriptor_tree *desc;
3177 rtx symbol, rtl;
3178 char label[256];
3179 int labelno;
3180 tree decl;
3182 desc = ggc_alloc<constant_descriptor_tree> ();
3183 desc->value = exp;
3185 /* Create a string containing the label name, in LABEL. */
3186 labelno = const_labelno++;
3187 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3189 /* Construct the VAR_DECL associated with the constant. */
3190 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3191 TREE_TYPE (exp));
3192 DECL_ARTIFICIAL (decl) = 1;
3193 DECL_IGNORED_P (decl) = 1;
3194 TREE_READONLY (decl) = 1;
3195 TREE_STATIC (decl) = 1;
3196 TREE_ADDRESSABLE (decl) = 1;
3197 /* We don't set the RTL yet as this would cause varpool to assume that the
3198 variable is referenced. Moreover, it would just be dropped in LTO mode.
3199 Instead we set the flag that will be recognized in make_decl_rtl. */
3200 DECL_IN_CONSTANT_POOL (decl) = 1;
3201 DECL_INITIAL (decl) = desc->value;
3202 /* ??? CONSTANT_ALIGNMENT hasn't been updated for vector types on most
3203 architectures so use DATA_ALIGNMENT as well, except for strings. */
3204 if (TREE_CODE (exp) == STRING_CST)
3206 #ifdef CONSTANT_ALIGNMENT
3207 DECL_ALIGN (decl) = CONSTANT_ALIGNMENT (exp, DECL_ALIGN (decl));
3208 #endif
3210 else
3211 align_variable (decl, 0);
3213 /* Now construct the SYMBOL_REF and the MEM. */
3214 if (use_object_blocks_p ())
3216 section *sect = get_constant_section (exp, DECL_ALIGN (decl));
3217 symbol = create_block_symbol (ggc_strdup (label),
3218 get_block_for_section (sect), -1);
3220 else
3221 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3222 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3223 SET_SYMBOL_REF_DECL (symbol, decl);
3224 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3226 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3227 set_mem_attributes (rtl, exp, 1);
3228 set_mem_alias_set (rtl, 0);
3229 set_mem_alias_set (rtl, const_alias_set);
3231 /* We cannot share RTX'es in pool entries.
3232 Mark this piece of RTL as required for unsharing. */
3233 RTX_FLAG (rtl, used) = 1;
3235 /* Set flags or add text to the name to record information, such as
3236 that it is a local symbol. If the name is changed, the macro
3237 ASM_OUTPUT_LABELREF will have to know how to strip this
3238 information. This call might invalidate our local variable
3239 SYMBOL; we can't use it afterward. */
3240 targetm.encode_section_info (exp, rtl, true);
3242 desc->rtl = rtl;
3244 return desc;
3247 /* Return an rtx representing a reference to constant data in memory
3248 for the constant expression EXP.
3250 If assembler code for such a constant has already been output,
3251 return an rtx to refer to it.
3252 Otherwise, output such a constant in memory
3253 and generate an rtx for it.
3255 If DEFER is nonzero, this constant can be deferred and output only
3256 if referenced in the function after all optimizations.
3258 `const_desc_table' records which constants already have label strings. */
3261 output_constant_def (tree exp, int defer)
3263 struct constant_descriptor_tree *desc;
3264 struct constant_descriptor_tree key;
3265 void **loc;
3267 /* Look up EXP in the table of constant descriptors. If we didn't find
3268 it, create a new one. */
3269 key.value = exp;
3270 key.hash = const_hash_1 (exp);
3271 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3273 desc = (struct constant_descriptor_tree *) *loc;
3274 if (desc == 0)
3276 desc = build_constant_desc (exp);
3277 desc->hash = key.hash;
3278 *loc = desc;
3281 maybe_output_constant_def_contents (desc, defer);
3282 return desc->rtl;
3285 /* Subroutine of output_constant_def: Decide whether or not we need to
3286 output the constant DESC now, and if so, do it. */
3287 static void
3288 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3289 int defer)
3291 rtx symbol = XEXP (desc->rtl, 0);
3292 tree exp = desc->value;
3294 if (flag_syntax_only)
3295 return;
3297 if (TREE_ASM_WRITTEN (exp))
3298 /* Already output; don't do it again. */
3299 return;
3301 /* We can always defer constants as long as the context allows
3302 doing so. */
3303 if (defer)
3305 /* Increment n_deferred_constants if it exists. It needs to be at
3306 least as large as the number of constants actually referred to
3307 by the function. If it's too small we'll stop looking too early
3308 and fail to emit constants; if it's too large we'll only look
3309 through the entire function when we could have stopped earlier. */
3310 if (cfun)
3311 n_deferred_constants++;
3312 return;
3315 output_constant_def_contents (symbol);
3318 /* Subroutine of output_constant_def_contents. Output the definition
3319 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3320 constant's alignment in bits. */
3322 static void
3323 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3325 HOST_WIDE_INT size;
3327 size = get_constant_size (exp);
3329 /* Do any machine/system dependent processing of the constant. */
3330 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3332 /* Output the value of EXP. */
3333 output_constant (exp, size, align);
3336 /* We must output the constant data referred to by SYMBOL; do so. */
3338 static void
3339 output_constant_def_contents (rtx symbol)
3341 tree decl = SYMBOL_REF_DECL (symbol);
3342 tree exp = DECL_INITIAL (decl);
3343 unsigned int align;
3344 bool asan_protected = false;
3346 /* Make sure any other constants whose addresses appear in EXP
3347 are assigned label numbers. */
3348 output_addressed_constants (exp);
3350 /* We are no longer deferring this constant. */
3351 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3353 if ((flag_sanitize & SANITIZE_ADDRESS)
3354 && TREE_CODE (exp) == STRING_CST
3355 && asan_protect_global (exp))
3357 asan_protected = true;
3358 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
3359 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
3362 /* If the constant is part of an object block, make sure that the
3363 decl has been positioned within its block, but do not write out
3364 its definition yet. output_object_blocks will do that later. */
3365 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3366 place_block_symbol (symbol);
3367 else
3369 align = DECL_ALIGN (decl);
3370 switch_to_section (get_constant_section (exp, align));
3371 if (align > BITS_PER_UNIT)
3372 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3373 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3374 if (asan_protected)
3376 HOST_WIDE_INT size = get_constant_size (exp);
3377 assemble_zeros (asan_red_zone_size (size));
3382 /* Look up EXP in the table of constant descriptors. Return the rtl
3383 if it has been emitted, else null. */
3386 lookup_constant_def (tree exp)
3388 struct constant_descriptor_tree *desc;
3389 struct constant_descriptor_tree key;
3391 key.value = exp;
3392 key.hash = const_hash_1 (exp);
3393 desc = (struct constant_descriptor_tree *)
3394 htab_find_with_hash (const_desc_htab, &key, key.hash);
3396 return (desc ? desc->rtl : NULL_RTX);
3399 /* Return a tree representing a reference to constant data in memory
3400 for the constant expression EXP.
3402 This is the counterpart of output_constant_def at the Tree level. */
3404 tree
3405 tree_output_constant_def (tree exp)
3407 struct constant_descriptor_tree *desc, key;
3408 void **loc;
3409 tree decl;
3411 /* Look up EXP in the table of constant descriptors. If we didn't find
3412 it, create a new one. */
3413 key.value = exp;
3414 key.hash = const_hash_1 (exp);
3415 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3417 desc = (struct constant_descriptor_tree *) *loc;
3418 if (desc == 0)
3420 desc = build_constant_desc (exp);
3421 desc->hash = key.hash;
3422 *loc = desc;
3425 decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3426 varpool_node::finalize_decl (decl);
3427 return decl;
3430 /* Used in the hash tables to avoid outputting the same constant
3431 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3432 are output once per function, not once per file. */
3433 /* ??? Only a few targets need per-function constant pools. Most
3434 can use one per-file pool. Should add a targetm bit to tell the
3435 difference. */
3437 struct GTY(()) rtx_constant_pool {
3438 /* Pointers to first and last constant in pool, as ordered by offset. */
3439 struct constant_descriptor_rtx *first;
3440 struct constant_descriptor_rtx *last;
3442 /* Hash facility for making memory-constants from constant rtl-expressions.
3443 It is used on RISC machines where immediate integer arguments and
3444 constant addresses are restricted so that such constants must be stored
3445 in memory. */
3446 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_htab;
3448 /* Current offset in constant pool (does not include any
3449 machine-specific header). */
3450 HOST_WIDE_INT offset;
3453 struct GTY((chain_next ("%h.next"))) constant_descriptor_rtx {
3454 struct constant_descriptor_rtx *next;
3455 rtx mem;
3456 rtx sym;
3457 rtx constant;
3458 HOST_WIDE_INT offset;
3459 hashval_t hash;
3460 enum machine_mode mode;
3461 unsigned int align;
3462 int labelno;
3463 int mark;
3466 /* Hash and compare functions for const_rtx_htab. */
3468 static hashval_t
3469 const_desc_rtx_hash (const void *ptr)
3471 const struct constant_descriptor_rtx *const desc
3472 = (const struct constant_descriptor_rtx *) ptr;
3473 return desc->hash;
3476 static int
3477 const_desc_rtx_eq (const void *a, const void *b)
3479 const struct constant_descriptor_rtx *const x
3480 = (const struct constant_descriptor_rtx *) a;
3481 const struct constant_descriptor_rtx *const y
3482 = (const struct constant_descriptor_rtx *) b;
3484 if (x->mode != y->mode)
3485 return 0;
3486 return rtx_equal_p (x->constant, y->constant);
3489 /* Hash one component of a constant. */
3491 static hashval_t
3492 const_rtx_hash_1 (const_rtx x)
3494 unsigned HOST_WIDE_INT hwi;
3495 enum machine_mode mode;
3496 enum rtx_code code;
3497 hashval_t h;
3498 int i;
3500 code = GET_CODE (x);
3501 mode = GET_MODE (x);
3502 h = (hashval_t) code * 1048573 + mode;
3504 switch (code)
3506 case CONST_INT:
3507 hwi = INTVAL (x);
3509 fold_hwi:
3511 int shift = sizeof (hashval_t) * CHAR_BIT;
3512 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3514 h ^= (hashval_t) hwi;
3515 for (i = 1; i < n; ++i)
3517 hwi >>= shift;
3518 h ^= (hashval_t) hwi;
3521 break;
3523 case CONST_WIDE_INT:
3524 hwi = GET_MODE_PRECISION (mode);
3526 for (i = 0; i < CONST_WIDE_INT_NUNITS (x); i++)
3527 hwi ^= CONST_WIDE_INT_ELT (x, i);
3528 goto fold_hwi;
3531 case CONST_DOUBLE:
3532 if (TARGET_SUPPORTS_WIDE_INT == 0 && mode == VOIDmode)
3534 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3535 goto fold_hwi;
3537 else
3538 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3539 break;
3541 case CONST_FIXED:
3542 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3543 break;
3545 case SYMBOL_REF:
3546 h ^= htab_hash_string (XSTR (x, 0));
3547 break;
3549 case LABEL_REF:
3550 h = h * 251 + CODE_LABEL_NUMBER (XEXP (x, 0));
3551 break;
3553 case UNSPEC:
3554 case UNSPEC_VOLATILE:
3555 h = h * 251 + XINT (x, 1);
3556 break;
3558 default:
3559 break;
3562 return h;
3565 /* Compute a hash value for X, which should be a constant. */
3567 static hashval_t
3568 const_rtx_hash (rtx x)
3570 hashval_t h = 0;
3571 subrtx_iterator::array_type array;
3572 FOR_EACH_SUBRTX (iter, array, x, ALL)
3573 h = h * 509 + const_rtx_hash_1 (*iter);
3574 return h;
3578 /* Create and return a new rtx constant pool. */
3580 static struct rtx_constant_pool *
3581 create_constant_pool (void)
3583 struct rtx_constant_pool *pool;
3585 pool = ggc_alloc<rtx_constant_pool> ();
3586 pool->const_rtx_htab = htab_create_ggc (31, const_desc_rtx_hash,
3587 const_desc_rtx_eq, NULL);
3588 pool->first = NULL;
3589 pool->last = NULL;
3590 pool->offset = 0;
3591 return pool;
3594 /* Initialize constant pool hashing for a new function. */
3596 void
3597 init_varasm_status (void)
3599 crtl->varasm.pool = create_constant_pool ();
3600 crtl->varasm.deferred_constants = 0;
3603 /* Given a MINUS expression, simplify it if both sides
3604 include the same symbol. */
3607 simplify_subtraction (rtx x)
3609 rtx r = simplify_rtx (x);
3610 return r ? r : x;
3613 /* Given a constant rtx X, make (or find) a memory constant for its value
3614 and return a MEM rtx to refer to it in memory. */
3617 force_const_mem (enum machine_mode mode, rtx x)
3619 struct constant_descriptor_rtx *desc, tmp;
3620 struct rtx_constant_pool *pool;
3621 char label[256];
3622 rtx def, symbol;
3623 hashval_t hash;
3624 unsigned int align;
3625 void **slot;
3627 /* If we're not allowed to drop X into the constant pool, don't. */
3628 if (targetm.cannot_force_const_mem (mode, x))
3629 return NULL_RTX;
3631 /* Record that this function has used a constant pool entry. */
3632 crtl->uses_const_pool = 1;
3634 /* Decide which pool to use. */
3635 pool = (targetm.use_blocks_for_constant_p (mode, x)
3636 ? shared_constant_pool
3637 : crtl->varasm.pool);
3639 /* Lookup the value in the hashtable. */
3640 tmp.constant = x;
3641 tmp.mode = mode;
3642 hash = const_rtx_hash (x);
3643 slot = htab_find_slot_with_hash (pool->const_rtx_htab, &tmp, hash, INSERT);
3644 desc = (struct constant_descriptor_rtx *) *slot;
3646 /* If the constant was already present, return its memory. */
3647 if (desc)
3648 return copy_rtx (desc->mem);
3650 /* Otherwise, create a new descriptor. */
3651 desc = ggc_alloc<constant_descriptor_rtx> ();
3652 *slot = desc;
3654 /* Align the location counter as required by EXP's data type. */
3655 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3656 #ifdef CONSTANT_ALIGNMENT
3658 tree type = lang_hooks.types.type_for_mode (mode, 0);
3659 if (type != NULL_TREE)
3660 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3662 #endif
3664 pool->offset += (align / BITS_PER_UNIT) - 1;
3665 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3667 desc->next = NULL;
3668 desc->constant = copy_rtx (tmp.constant);
3669 desc->offset = pool->offset;
3670 desc->hash = hash;
3671 desc->mode = mode;
3672 desc->align = align;
3673 desc->labelno = const_labelno;
3674 desc->mark = 0;
3676 pool->offset += GET_MODE_SIZE (mode);
3677 if (pool->last)
3678 pool->last->next = desc;
3679 else
3680 pool->first = pool->last = desc;
3681 pool->last = desc;
3683 /* Create a string containing the label name, in LABEL. */
3684 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3685 ++const_labelno;
3687 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3688 the constants pool. */
3689 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3691 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3692 symbol = create_block_symbol (ggc_strdup (label),
3693 get_block_for_section (sect), -1);
3695 else
3696 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3697 desc->sym = symbol;
3698 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3699 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3700 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3702 /* Construct the MEM. */
3703 desc->mem = def = gen_const_mem (mode, symbol);
3704 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3705 set_mem_align (def, align);
3707 /* If we're dropping a label to the constant pool, make sure we
3708 don't delete it. */
3709 if (GET_CODE (x) == LABEL_REF)
3710 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3712 return copy_rtx (def);
3715 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3718 get_pool_constant (const_rtx addr)
3720 return SYMBOL_REF_CONSTANT (addr)->constant;
3723 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3724 and whether it has been output or not. */
3727 get_pool_constant_mark (rtx addr, bool *pmarked)
3729 struct constant_descriptor_rtx *desc;
3731 desc = SYMBOL_REF_CONSTANT (addr);
3732 *pmarked = (desc->mark != 0);
3733 return desc->constant;
3736 /* Similar, return the mode. */
3738 enum machine_mode
3739 get_pool_mode (const_rtx addr)
3741 return SYMBOL_REF_CONSTANT (addr)->mode;
3744 /* Return the size of the constant pool. */
3747 get_pool_size (void)
3749 return crtl->varasm.pool->offset;
3752 /* Worker function for output_constant_pool_1. Emit assembly for X
3753 in MODE with known alignment ALIGN. */
3755 static void
3756 output_constant_pool_2 (enum machine_mode mode, rtx x, unsigned int align)
3758 switch (GET_MODE_CLASS (mode))
3760 case MODE_FLOAT:
3761 case MODE_DECIMAL_FLOAT:
3763 REAL_VALUE_TYPE r;
3765 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3766 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3767 assemble_real (r, mode, align);
3768 break;
3771 case MODE_INT:
3772 case MODE_PARTIAL_INT:
3773 case MODE_FRACT:
3774 case MODE_UFRACT:
3775 case MODE_ACCUM:
3776 case MODE_UACCUM:
3777 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3778 break;
3780 case MODE_VECTOR_FLOAT:
3781 case MODE_VECTOR_INT:
3782 case MODE_VECTOR_FRACT:
3783 case MODE_VECTOR_UFRACT:
3784 case MODE_VECTOR_ACCUM:
3785 case MODE_VECTOR_UACCUM:
3787 int i, units;
3788 enum machine_mode submode = GET_MODE_INNER (mode);
3789 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3791 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3792 units = CONST_VECTOR_NUNITS (x);
3794 for (i = 0; i < units; i++)
3796 rtx elt = CONST_VECTOR_ELT (x, i);
3797 output_constant_pool_2 (submode, elt, i ? subalign : align);
3800 break;
3802 default:
3803 gcc_unreachable ();
3807 /* Worker function for output_constant_pool. Emit constant DESC,
3808 giving it ALIGN bits of alignment. */
3810 static void
3811 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3812 unsigned int align)
3814 rtx x, tmp;
3816 x = desc->constant;
3818 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3819 whose CODE_LABEL has been deleted. This can occur if a jump table
3820 is eliminated by optimization. If so, write a constant of zero
3821 instead. Note that this can also happen by turning the
3822 CODE_LABEL into a NOTE. */
3823 /* ??? This seems completely and utterly wrong. Certainly it's
3824 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3825 functioning even with INSN_DELETED_P and friends. */
3827 tmp = x;
3828 switch (GET_CODE (tmp))
3830 case CONST:
3831 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3832 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
3833 break;
3834 tmp = XEXP (XEXP (tmp, 0), 0);
3835 /* FALLTHRU */
3837 case LABEL_REF:
3838 tmp = XEXP (tmp, 0);
3839 gcc_assert (!INSN_DELETED_P (tmp));
3840 gcc_assert (!NOTE_P (tmp)
3841 || NOTE_KIND (tmp) != NOTE_INSN_DELETED);
3842 break;
3844 default:
3845 break;
3848 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3849 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3850 align, desc->labelno, done);
3851 #endif
3853 assemble_align (align);
3855 /* Output the label. */
3856 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3858 /* Output the data. */
3859 output_constant_pool_2 (desc->mode, x, align);
3861 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3862 sections have proper size. */
3863 if (align > GET_MODE_BITSIZE (desc->mode)
3864 && in_section
3865 && (in_section->common.flags & SECTION_MERGE))
3866 assemble_align (align);
3868 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3869 done:
3870 #endif
3871 return;
3874 /* Mark all constants that are referenced by SYMBOL_REFs in X.
3875 Emit referenced deferred strings. */
3877 static void
3878 mark_constants_in_pattern (rtx insn)
3880 subrtx_iterator::array_type array;
3881 FOR_EACH_SUBRTX (iter, array, PATTERN (insn), ALL)
3883 const_rtx x = *iter;
3884 if (GET_CODE (x) == SYMBOL_REF)
3886 if (CONSTANT_POOL_ADDRESS_P (x))
3888 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
3889 if (desc->mark == 0)
3891 desc->mark = 1;
3892 iter.substitute (desc->constant);
3895 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3897 tree decl = SYMBOL_REF_DECL (x);
3898 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
3900 n_deferred_constants--;
3901 output_constant_def_contents (CONST_CAST_RTX (x));
3908 /* Look through appropriate parts of INSN, marking all entries in the
3909 constant pool which are actually being used. Entries that are only
3910 referenced by other constants are also marked as used. Emit
3911 deferred strings that are used. */
3913 static void
3914 mark_constants (rtx_insn *insn)
3916 if (!INSN_P (insn))
3917 return;
3919 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3920 insns, not any notes that may be attached. We don't want to mark
3921 a constant just because it happens to appear in a REG_EQUIV note. */
3922 if (rtx_sequence *seq = dyn_cast <rtx_sequence *> (PATTERN (insn)))
3924 int i, n = seq->len ();
3925 for (i = 0; i < n; ++i)
3927 rtx subinsn = seq->element (i);
3928 if (INSN_P (subinsn))
3929 mark_constants_in_pattern (subinsn);
3932 else
3933 mark_constants_in_pattern (insn);
3936 /* Look through the instructions for this function, and mark all the
3937 entries in POOL which are actually being used. Emit deferred constants
3938 which have indeed been used. */
3940 static void
3941 mark_constant_pool (void)
3943 rtx_insn *insn;
3945 if (!crtl->uses_const_pool && n_deferred_constants == 0)
3946 return;
3948 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3949 mark_constants (insn);
3952 /* Write all the constants in POOL. */
3954 static void
3955 output_constant_pool_contents (struct rtx_constant_pool *pool)
3957 struct constant_descriptor_rtx *desc;
3959 for (desc = pool->first; desc ; desc = desc->next)
3960 if (desc->mark)
3962 /* If the constant is part of an object_block, make sure that
3963 the constant has been positioned within its block, but do not
3964 write out its definition yet. output_object_blocks will do
3965 that later. */
3966 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
3967 && SYMBOL_REF_BLOCK (desc->sym))
3968 place_block_symbol (desc->sym);
3969 else
3971 switch_to_section (targetm.asm_out.select_rtx_section
3972 (desc->mode, desc->constant, desc->align));
3973 output_constant_pool_1 (desc, desc->align);
3978 /* Mark all constants that are used in the current function, then write
3979 out the function's private constant pool. */
3981 static void
3982 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
3983 tree fndecl ATTRIBUTE_UNUSED)
3985 struct rtx_constant_pool *pool = crtl->varasm.pool;
3987 /* It is possible for gcc to call force_const_mem and then to later
3988 discard the instructions which refer to the constant. In such a
3989 case we do not need to output the constant. */
3990 mark_constant_pool ();
3992 #ifdef ASM_OUTPUT_POOL_PROLOGUE
3993 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
3994 #endif
3996 output_constant_pool_contents (pool);
3998 #ifdef ASM_OUTPUT_POOL_EPILOGUE
3999 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
4000 #endif
4003 /* Write the contents of the shared constant pool. */
4005 void
4006 output_shared_constant_pool (void)
4008 output_constant_pool_contents (shared_constant_pool);
4011 /* Determine what kind of relocations EXP may need. */
4014 compute_reloc_for_constant (tree exp)
4016 int reloc = 0, reloc2;
4017 tree tem;
4019 switch (TREE_CODE (exp))
4021 case ADDR_EXPR:
4022 case FDESC_EXPR:
4023 /* Go inside any operations that get_inner_reference can handle and see
4024 if what's inside is a constant: no need to do anything here for
4025 addresses of variables or functions. */
4026 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4027 tem = TREE_OPERAND (tem, 0))
4030 if (TREE_CODE (tem) == MEM_REF
4031 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4033 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4034 break;
4037 if (!targetm.binds_local_p (tem))
4038 reloc |= 2;
4039 else
4040 reloc |= 1;
4041 break;
4043 case PLUS_EXPR:
4044 case POINTER_PLUS_EXPR:
4045 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4046 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4047 break;
4049 case MINUS_EXPR:
4050 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4051 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4052 /* The difference of two local labels is computable at link time. */
4053 if (reloc == 1 && reloc2 == 1)
4054 reloc = 0;
4055 else
4056 reloc |= reloc2;
4057 break;
4059 CASE_CONVERT:
4060 case VIEW_CONVERT_EXPR:
4061 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4062 break;
4064 case CONSTRUCTOR:
4066 unsigned HOST_WIDE_INT idx;
4067 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4068 if (tem != 0)
4069 reloc |= compute_reloc_for_constant (tem);
4071 break;
4073 default:
4074 break;
4076 return reloc;
4079 /* Find all the constants whose addresses are referenced inside of EXP,
4080 and make sure assembler code with a label has been output for each one.
4081 Indicate whether an ADDR_EXPR has been encountered. */
4083 static void
4084 output_addressed_constants (tree exp)
4086 tree tem;
4088 switch (TREE_CODE (exp))
4090 case ADDR_EXPR:
4091 case FDESC_EXPR:
4092 /* Go inside any operations that get_inner_reference can handle and see
4093 if what's inside is a constant: no need to do anything here for
4094 addresses of variables or functions. */
4095 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4096 tem = TREE_OPERAND (tem, 0))
4099 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4100 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4101 tem = DECL_INITIAL (tem);
4103 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4104 output_constant_def (tem, 0);
4106 if (TREE_CODE (tem) == MEM_REF)
4107 output_addressed_constants (TREE_OPERAND (tem, 0));
4108 break;
4110 case PLUS_EXPR:
4111 case POINTER_PLUS_EXPR:
4112 case MINUS_EXPR:
4113 output_addressed_constants (TREE_OPERAND (exp, 1));
4114 /* Fall through. */
4116 CASE_CONVERT:
4117 case VIEW_CONVERT_EXPR:
4118 output_addressed_constants (TREE_OPERAND (exp, 0));
4119 break;
4121 case CONSTRUCTOR:
4123 unsigned HOST_WIDE_INT idx;
4124 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4125 if (tem != 0)
4126 output_addressed_constants (tem);
4128 break;
4130 default:
4131 break;
4135 /* Whether a constructor CTOR is a valid static constant initializer if all
4136 its elements are. This used to be internal to initializer_constant_valid_p
4137 and has been exposed to let other functions like categorize_ctor_elements
4138 evaluate the property while walking a constructor for other purposes. */
4140 bool
4141 constructor_static_from_elts_p (const_tree ctor)
4143 return (TREE_CONSTANT (ctor)
4144 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4145 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4146 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4149 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4150 tree *cache);
4152 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4153 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4154 which are valid when ENDTYPE is an integer of any size; in
4155 particular, this does not accept a pointer minus a constant. This
4156 returns null_pointer_node if the VALUE is an absolute constant
4157 which can be used to initialize a static variable. Otherwise it
4158 returns NULL. */
4160 static tree
4161 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4163 tree op0, op1;
4165 if (!INTEGRAL_TYPE_P (endtype))
4166 return NULL_TREE;
4168 op0 = TREE_OPERAND (value, 0);
4169 op1 = TREE_OPERAND (value, 1);
4171 /* Like STRIP_NOPS except allow the operand mode to widen. This
4172 works around a feature of fold that simplifies (int)(p1 - p2) to
4173 ((int)p1 - (int)p2) under the theory that the narrower operation
4174 is cheaper. */
4176 while (CONVERT_EXPR_P (op0)
4177 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4179 tree inner = TREE_OPERAND (op0, 0);
4180 if (inner == error_mark_node
4181 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4182 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
4183 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4184 break;
4185 op0 = inner;
4188 while (CONVERT_EXPR_P (op1)
4189 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4191 tree inner = TREE_OPERAND (op1, 0);
4192 if (inner == error_mark_node
4193 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4194 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
4195 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4196 break;
4197 op1 = inner;
4200 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4201 if (!op0)
4202 return NULL_TREE;
4204 op1 = initializer_constant_valid_p_1 (op1, endtype,
4205 cache ? cache + 2 : NULL);
4206 /* Both initializers must be known. */
4207 if (op1)
4209 if (op0 == op1
4210 && (op0 == null_pointer_node
4211 || TREE_CODE (value) == MINUS_EXPR))
4212 return null_pointer_node;
4214 /* Support differences between labels. */
4215 if (TREE_CODE (op0) == LABEL_DECL
4216 && TREE_CODE (op1) == LABEL_DECL)
4217 return null_pointer_node;
4219 if (TREE_CODE (op0) == STRING_CST
4220 && TREE_CODE (op1) == STRING_CST
4221 && operand_equal_p (op0, op1, 1))
4222 return null_pointer_node;
4225 return NULL_TREE;
4228 /* Helper function of initializer_constant_valid_p.
4229 Return nonzero if VALUE is a valid constant-valued expression
4230 for use in initializing a static variable; one that can be an
4231 element of a "constant" initializer.
4233 Return null_pointer_node if the value is absolute;
4234 if it is relocatable, return the variable that determines the relocation.
4235 We assume that VALUE has been folded as much as possible;
4236 therefore, we do not need to check for such things as
4237 arithmetic-combinations of integers.
4239 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4241 static tree
4242 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4244 tree ret;
4246 switch (TREE_CODE (value))
4248 case CONSTRUCTOR:
4249 if (constructor_static_from_elts_p (value))
4251 unsigned HOST_WIDE_INT idx;
4252 tree elt;
4253 bool absolute = true;
4255 if (cache && cache[0] == value)
4256 return cache[1];
4257 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4259 tree reloc;
4260 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4261 NULL);
4262 if (!reloc)
4264 if (cache)
4266 cache[0] = value;
4267 cache[1] = NULL_TREE;
4269 return NULL_TREE;
4271 if (reloc != null_pointer_node)
4272 absolute = false;
4274 /* For a non-absolute relocation, there is no single
4275 variable that can be "the variable that determines the
4276 relocation." */
4277 if (cache)
4279 cache[0] = value;
4280 cache[1] = absolute ? null_pointer_node : error_mark_node;
4282 return absolute ? null_pointer_node : error_mark_node;
4285 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4287 case INTEGER_CST:
4288 case VECTOR_CST:
4289 case REAL_CST:
4290 case FIXED_CST:
4291 case STRING_CST:
4292 case COMPLEX_CST:
4293 return null_pointer_node;
4295 case ADDR_EXPR:
4296 case FDESC_EXPR:
4298 tree op0 = staticp (TREE_OPERAND (value, 0));
4299 if (op0)
4301 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4302 to be a constant, this is old-skool offsetof-like nonsense. */
4303 if (TREE_CODE (op0) == INDIRECT_REF
4304 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4305 return null_pointer_node;
4306 /* Taking the address of a nested function involves a trampoline,
4307 unless we don't need or want one. */
4308 if (TREE_CODE (op0) == FUNCTION_DECL
4309 && DECL_STATIC_CHAIN (op0)
4310 && !TREE_NO_TRAMPOLINE (value))
4311 return NULL_TREE;
4312 /* "&{...}" requires a temporary to hold the constructed
4313 object. */
4314 if (TREE_CODE (op0) == CONSTRUCTOR)
4315 return NULL_TREE;
4317 return op0;
4320 case NON_LVALUE_EXPR:
4321 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4322 endtype, cache);
4324 case VIEW_CONVERT_EXPR:
4326 tree src = TREE_OPERAND (value, 0);
4327 tree src_type = TREE_TYPE (src);
4328 tree dest_type = TREE_TYPE (value);
4330 /* Allow view-conversions from aggregate to non-aggregate type only
4331 if the bit pattern is fully preserved afterwards; otherwise, the
4332 RTL expander won't be able to apply a subsequent transformation
4333 to the underlying constructor. */
4334 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4336 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4337 return initializer_constant_valid_p_1 (src, endtype, cache);
4338 else
4339 return NULL_TREE;
4342 /* Allow all other kinds of view-conversion. */
4343 return initializer_constant_valid_p_1 (src, endtype, cache);
4346 CASE_CONVERT:
4348 tree src = TREE_OPERAND (value, 0);
4349 tree src_type = TREE_TYPE (src);
4350 tree dest_type = TREE_TYPE (value);
4352 /* Allow conversions between pointer types, floating-point
4353 types, and offset types. */
4354 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4355 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4356 || (TREE_CODE (dest_type) == OFFSET_TYPE
4357 && TREE_CODE (src_type) == OFFSET_TYPE))
4358 return initializer_constant_valid_p_1 (src, endtype, cache);
4360 /* Allow length-preserving conversions between integer types. */
4361 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4362 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4363 return initializer_constant_valid_p_1 (src, endtype, cache);
4365 /* Allow conversions between other integer types only if
4366 explicit value. */
4367 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type))
4369 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4370 if (inner == null_pointer_node)
4371 return null_pointer_node;
4372 break;
4375 /* Allow (int) &foo provided int is as wide as a pointer. */
4376 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4377 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4378 return initializer_constant_valid_p_1 (src, endtype, cache);
4380 /* Likewise conversions from int to pointers, but also allow
4381 conversions from 0. */
4382 if ((POINTER_TYPE_P (dest_type)
4383 || TREE_CODE (dest_type) == OFFSET_TYPE)
4384 && INTEGRAL_TYPE_P (src_type))
4386 if (TREE_CODE (src) == INTEGER_CST
4387 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4388 return null_pointer_node;
4389 if (integer_zerop (src))
4390 return null_pointer_node;
4391 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4392 return initializer_constant_valid_p_1 (src, endtype, cache);
4395 /* Allow conversions to struct or union types if the value
4396 inside is okay. */
4397 if (TREE_CODE (dest_type) == RECORD_TYPE
4398 || TREE_CODE (dest_type) == UNION_TYPE)
4399 return initializer_constant_valid_p_1 (src, endtype, cache);
4401 break;
4403 case POINTER_PLUS_EXPR:
4404 case PLUS_EXPR:
4405 /* Any valid floating-point constants will have been folded by now;
4406 with -frounding-math we hit this with addition of two constants. */
4407 if (TREE_CODE (endtype) == REAL_TYPE)
4408 return NULL_TREE;
4409 if (cache && cache[0] == value)
4410 return cache[1];
4411 if (! INTEGRAL_TYPE_P (endtype)
4412 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4414 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4415 tree valid0
4416 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4417 endtype, ncache);
4418 tree valid1
4419 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4420 endtype, ncache + 2);
4421 /* If either term is absolute, use the other term's relocation. */
4422 if (valid0 == null_pointer_node)
4423 ret = valid1;
4424 else if (valid1 == null_pointer_node)
4425 ret = valid0;
4426 /* Support narrowing pointer differences. */
4427 else
4428 ret = narrowing_initializer_constant_valid_p (value, endtype,
4429 ncache);
4431 else
4432 /* Support narrowing pointer differences. */
4433 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4434 if (cache)
4436 cache[0] = value;
4437 cache[1] = ret;
4439 return ret;
4441 case MINUS_EXPR:
4442 if (TREE_CODE (endtype) == REAL_TYPE)
4443 return NULL_TREE;
4444 if (cache && cache[0] == value)
4445 return cache[1];
4446 if (! INTEGRAL_TYPE_P (endtype)
4447 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4449 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4450 tree valid0
4451 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4452 endtype, ncache);
4453 tree valid1
4454 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4455 endtype, ncache + 2);
4456 /* Win if second argument is absolute. */
4457 if (valid1 == null_pointer_node)
4458 ret = valid0;
4459 /* Win if both arguments have the same relocation.
4460 Then the value is absolute. */
4461 else if (valid0 == valid1 && valid0 != 0)
4462 ret = null_pointer_node;
4463 /* Since GCC guarantees that string constants are unique in the
4464 generated code, a subtraction between two copies of the same
4465 constant string is absolute. */
4466 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4467 && valid1 && TREE_CODE (valid1) == STRING_CST
4468 && operand_equal_p (valid0, valid1, 1))
4469 ret = null_pointer_node;
4470 /* Support narrowing differences. */
4471 else
4472 ret = narrowing_initializer_constant_valid_p (value, endtype,
4473 ncache);
4475 else
4476 /* Support narrowing differences. */
4477 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4478 if (cache)
4480 cache[0] = value;
4481 cache[1] = ret;
4483 return ret;
4485 default:
4486 break;
4489 return NULL_TREE;
4492 /* Return nonzero if VALUE is a valid constant-valued expression
4493 for use in initializing a static variable; one that can be an
4494 element of a "constant" initializer.
4496 Return null_pointer_node if the value is absolute;
4497 if it is relocatable, return the variable that determines the relocation.
4498 We assume that VALUE has been folded as much as possible;
4499 therefore, we do not need to check for such things as
4500 arithmetic-combinations of integers. */
4501 tree
4502 initializer_constant_valid_p (tree value, tree endtype)
4504 return initializer_constant_valid_p_1 (value, endtype, NULL);
4507 /* Return true if VALUE is a valid constant-valued expression
4508 for use in initializing a static bit-field; one that can be
4509 an element of a "constant" initializer. */
4511 bool
4512 initializer_constant_valid_for_bitfield_p (tree value)
4514 /* For bitfields we support integer constants or possibly nested aggregates
4515 of such. */
4516 switch (TREE_CODE (value))
4518 case CONSTRUCTOR:
4520 unsigned HOST_WIDE_INT idx;
4521 tree elt;
4523 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4524 if (!initializer_constant_valid_for_bitfield_p (elt))
4525 return false;
4526 return true;
4529 case INTEGER_CST:
4530 case REAL_CST:
4531 return true;
4533 case VIEW_CONVERT_EXPR:
4534 case NON_LVALUE_EXPR:
4535 return
4536 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4538 default:
4539 break;
4542 return false;
4545 /* output_constructor outer state of relevance in recursive calls, typically
4546 for nested aggregate bitfields. */
4548 typedef struct {
4549 unsigned int bit_offset; /* current position in ... */
4550 int byte; /* ... the outer byte buffer. */
4551 } oc_outer_state;
4553 static unsigned HOST_WIDE_INT
4554 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int,
4555 oc_outer_state *);
4557 /* Output assembler code for constant EXP, with no label.
4558 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4559 Assumes output_addressed_constants has been done on EXP already.
4561 Generate at least SIZE bytes of assembler data, padding at the end
4562 with zeros if necessary. SIZE must always be specified. The returned
4563 value is the actual number of bytes of assembler data generated, which
4564 may be bigger than SIZE if the object contains a variable length field.
4566 SIZE is important for structure constructors,
4567 since trailing members may have been omitted from the constructor.
4568 It is also important for initialization of arrays from string constants
4569 since the full length of the string constant might not be wanted.
4570 It is also needed for initialization of unions, where the initializer's
4571 type is just one member, and that may not be as long as the union.
4573 There a case in which we would fail to output exactly SIZE bytes:
4574 for a structure constructor that wants to produce more than SIZE bytes.
4575 But such constructors will never be generated for any possible input.
4577 ALIGN is the alignment of the data in bits. */
4579 static unsigned HOST_WIDE_INT
4580 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align)
4582 enum tree_code code;
4583 unsigned HOST_WIDE_INT thissize;
4585 if (size == 0 || flag_syntax_only)
4586 return size;
4588 /* See if we're trying to initialize a pointer in a non-default mode
4589 to the address of some declaration somewhere. If the target says
4590 the mode is valid for pointers, assume the target has a way of
4591 resolving it. */
4592 if (TREE_CODE (exp) == NOP_EXPR
4593 && POINTER_TYPE_P (TREE_TYPE (exp))
4594 && targetm.addr_space.valid_pointer_mode
4595 (TYPE_MODE (TREE_TYPE (exp)),
4596 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4598 tree saved_type = TREE_TYPE (exp);
4600 /* Peel off any intermediate conversions-to-pointer for valid
4601 pointer modes. */
4602 while (TREE_CODE (exp) == NOP_EXPR
4603 && POINTER_TYPE_P (TREE_TYPE (exp))
4604 && targetm.addr_space.valid_pointer_mode
4605 (TYPE_MODE (TREE_TYPE (exp)),
4606 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4607 exp = TREE_OPERAND (exp, 0);
4609 /* If what we're left with is the address of something, we can
4610 convert the address to the final type and output it that
4611 way. */
4612 if (TREE_CODE (exp) == ADDR_EXPR)
4613 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4614 /* Likewise for constant ints. */
4615 else if (TREE_CODE (exp) == INTEGER_CST)
4616 exp = wide_int_to_tree (saved_type, exp);
4620 /* Eliminate any conversions since we'll be outputting the underlying
4621 constant. */
4622 while (CONVERT_EXPR_P (exp)
4623 || TREE_CODE (exp) == NON_LVALUE_EXPR
4624 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4626 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4627 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4629 /* Make sure eliminating the conversion is really a no-op, except with
4630 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4631 union types to allow for Ada unchecked unions. */
4632 if (type_size > op_size
4633 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4634 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4635 /* Keep the conversion. */
4636 break;
4637 else
4638 exp = TREE_OPERAND (exp, 0);
4641 code = TREE_CODE (TREE_TYPE (exp));
4642 thissize = int_size_in_bytes (TREE_TYPE (exp));
4644 /* Allow a constructor with no elements for any data type.
4645 This means to fill the space with zeros. */
4646 if (TREE_CODE (exp) == CONSTRUCTOR
4647 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4649 assemble_zeros (size);
4650 return size;
4653 if (TREE_CODE (exp) == FDESC_EXPR)
4655 #ifdef ASM_OUTPUT_FDESC
4656 HOST_WIDE_INT part = tree_to_shwi (TREE_OPERAND (exp, 1));
4657 tree decl = TREE_OPERAND (exp, 0);
4658 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4659 #else
4660 gcc_unreachable ();
4661 #endif
4662 return size;
4665 /* Now output the underlying data. If we've handling the padding, return.
4666 Otherwise, break and ensure SIZE is the size written. */
4667 switch (code)
4669 case BOOLEAN_TYPE:
4670 case INTEGER_TYPE:
4671 case ENUMERAL_TYPE:
4672 case POINTER_TYPE:
4673 case REFERENCE_TYPE:
4674 case OFFSET_TYPE:
4675 case FIXED_POINT_TYPE:
4676 case NULLPTR_TYPE:
4677 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
4678 EXPAND_INITIALIZER),
4679 MIN (size, thissize), align, 0))
4680 error ("initializer for integer/fixed-point value is too complicated");
4681 break;
4683 case REAL_TYPE:
4684 if (TREE_CODE (exp) != REAL_CST)
4685 error ("initializer for floating value is not a floating constant");
4686 else
4687 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)), align);
4688 break;
4690 case COMPLEX_TYPE:
4691 output_constant (TREE_REALPART (exp), thissize / 2, align);
4692 output_constant (TREE_IMAGPART (exp), thissize / 2,
4693 min_align (align, BITS_PER_UNIT * (thissize / 2)));
4694 break;
4696 case ARRAY_TYPE:
4697 case VECTOR_TYPE:
4698 switch (TREE_CODE (exp))
4700 case CONSTRUCTOR:
4701 return output_constructor (exp, size, align, NULL);
4702 case STRING_CST:
4703 thissize
4704 = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4705 assemble_string (TREE_STRING_POINTER (exp), thissize);
4706 break;
4707 case VECTOR_CST:
4709 enum machine_mode inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4710 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4711 int elt_size = GET_MODE_SIZE (inner);
4712 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align);
4713 thissize = elt_size;
4714 for (unsigned int i = 1; i < VECTOR_CST_NELTS (exp); i++)
4716 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign);
4717 thissize += elt_size;
4719 break;
4721 default:
4722 gcc_unreachable ();
4724 break;
4726 case RECORD_TYPE:
4727 case UNION_TYPE:
4728 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4729 return output_constructor (exp, size, align, NULL);
4731 case ERROR_MARK:
4732 return 0;
4734 default:
4735 gcc_unreachable ();
4738 if (size > thissize)
4739 assemble_zeros (size - thissize);
4741 return size;
4745 /* Subroutine of output_constructor, used for computing the size of
4746 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4747 type with an unspecified upper bound. */
4749 static unsigned HOST_WIDE_INT
4750 array_size_for_constructor (tree val)
4752 tree max_index;
4753 unsigned HOST_WIDE_INT cnt;
4754 tree index, value, tmp;
4755 offset_int i;
4757 /* This code used to attempt to handle string constants that are not
4758 arrays of single-bytes, but nothing else does, so there's no point in
4759 doing it here. */
4760 if (TREE_CODE (val) == STRING_CST)
4761 return TREE_STRING_LENGTH (val);
4763 max_index = NULL_TREE;
4764 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
4766 if (TREE_CODE (index) == RANGE_EXPR)
4767 index = TREE_OPERAND (index, 1);
4768 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
4769 max_index = index;
4772 if (max_index == NULL_TREE)
4773 return 0;
4775 /* Compute the total number of array elements. */
4776 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
4777 i = wi::to_offset (max_index) - wi::to_offset (tmp) + 1;
4779 /* Multiply by the array element unit size to find number of bytes. */
4780 i *= wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
4782 gcc_assert (wi::fits_uhwi_p (i));
4783 return i.to_uhwi ();
4786 /* Other datastructures + helpers for output_constructor. */
4788 /* output_constructor local state to support interaction with helpers. */
4790 typedef struct {
4792 /* Received arguments. */
4793 tree exp; /* Constructor expression. */
4794 tree type; /* Type of constructor expression. */
4795 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */
4796 unsigned int align; /* Known initial alignment. */
4797 tree min_index; /* Lower bound if specified for an array. */
4799 /* Output processing state. */
4800 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */
4801 int byte; /* Part of a bitfield byte yet to be output. */
4802 int last_relative_index; /* Implicit or explicit index of the last
4803 array element output within a bitfield. */
4804 bool byte_buffer_in_use; /* Whether BYTE is in use. */
4806 /* Current element. */
4807 tree field; /* Current field decl in a record. */
4808 tree val; /* Current element value. */
4809 tree index; /* Current element index. */
4811 } oc_local_state;
4813 /* Helper for output_constructor. From the current LOCAL state, output a
4814 RANGE_EXPR element. */
4816 static void
4817 output_constructor_array_range (oc_local_state *local)
4819 unsigned HOST_WIDE_INT fieldsize
4820 = int_size_in_bytes (TREE_TYPE (local->type));
4822 HOST_WIDE_INT lo_index
4823 = tree_to_shwi (TREE_OPERAND (local->index, 0));
4824 HOST_WIDE_INT hi_index
4825 = tree_to_shwi (TREE_OPERAND (local->index, 1));
4826 HOST_WIDE_INT index;
4828 unsigned int align2
4829 = min_align (local->align, fieldsize * BITS_PER_UNIT);
4831 for (index = lo_index; index <= hi_index; index++)
4833 /* Output the element's initial value. */
4834 if (local->val == NULL_TREE)
4835 assemble_zeros (fieldsize);
4836 else
4837 fieldsize = output_constant (local->val, fieldsize, align2);
4839 /* Count its size. */
4840 local->total_bytes += fieldsize;
4844 /* Helper for output_constructor. From the current LOCAL state, output a
4845 field element that is not true bitfield or part of an outer one. */
4847 static void
4848 output_constructor_regular_field (oc_local_state *local)
4850 /* Field size and position. Since this structure is static, we know the
4851 positions are constant. */
4852 unsigned HOST_WIDE_INT fieldsize;
4853 HOST_WIDE_INT fieldpos;
4855 unsigned int align2;
4857 if (local->index != NULL_TREE)
4859 /* Perform the index calculation in modulo arithmetic but
4860 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
4861 but we are using an unsigned sizetype. */
4862 unsigned prec = TYPE_PRECISION (sizetype);
4863 offset_int idx = wi::sext (wi::to_offset (local->index)
4864 - wi::to_offset (local->min_index), prec);
4865 fieldpos = (idx * wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (local->val))))
4866 .to_short_addr ();
4868 else if (local->field != NULL_TREE)
4869 fieldpos = int_byte_position (local->field);
4870 else
4871 fieldpos = 0;
4873 /* Output any buffered-up bit-fields preceding this element. */
4874 if (local->byte_buffer_in_use)
4876 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4877 local->total_bytes++;
4878 local->byte_buffer_in_use = false;
4881 /* Advance to offset of this element.
4882 Note no alignment needed in an array, since that is guaranteed
4883 if each element has the proper size. */
4884 if ((local->field != NULL_TREE || local->index != NULL_TREE)
4885 && fieldpos > local->total_bytes)
4887 assemble_zeros (fieldpos - local->total_bytes);
4888 local->total_bytes = fieldpos;
4891 /* Find the alignment of this element. */
4892 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
4894 /* Determine size this element should occupy. */
4895 if (local->field)
4897 fieldsize = 0;
4899 /* If this is an array with an unspecified upper bound,
4900 the initializer determines the size. */
4901 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
4902 but we cannot do this until the deprecated support for
4903 initializing zero-length array members is removed. */
4904 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
4905 && TYPE_DOMAIN (TREE_TYPE (local->field))
4906 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field))))
4908 fieldsize = array_size_for_constructor (local->val);
4909 /* Given a non-empty initialization, this field had
4910 better be last. */
4911 gcc_assert (!fieldsize || !DECL_CHAIN (local->field));
4913 else
4914 fieldsize = tree_to_uhwi (DECL_SIZE_UNIT (local->field));
4916 else
4917 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
4919 /* Output the element's initial value. */
4920 if (local->val == NULL_TREE)
4921 assemble_zeros (fieldsize);
4922 else
4923 fieldsize = output_constant (local->val, fieldsize, align2);
4925 /* Count its size. */
4926 local->total_bytes += fieldsize;
4929 /* Helper for output_constructor. From the LOCAL state, output an element
4930 that is a true bitfield or part of an outer one. BIT_OFFSET is the offset
4931 from the start of a possibly ongoing outer byte buffer. */
4933 static void
4934 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
4936 /* Bit size of this element. */
4937 HOST_WIDE_INT ebitsize
4938 = (local->field
4939 ? tree_to_uhwi (DECL_SIZE (local->field))
4940 : tree_to_uhwi (TYPE_SIZE (TREE_TYPE (local->type))));
4942 /* Relative index of this element if this is an array component. */
4943 HOST_WIDE_INT relative_index
4944 = (!local->field
4945 ? (local->index
4946 ? (tree_to_shwi (local->index)
4947 - tree_to_shwi (local->min_index))
4948 : local->last_relative_index + 1)
4949 : 0);
4951 /* Bit position of this element from the start of the containing
4952 constructor. */
4953 HOST_WIDE_INT constructor_relative_ebitpos
4954 = (local->field
4955 ? int_bit_position (local->field)
4956 : ebitsize * relative_index);
4958 /* Bit position of this element from the start of a possibly ongoing
4959 outer byte buffer. */
4960 HOST_WIDE_INT byte_relative_ebitpos
4961 = bit_offset + constructor_relative_ebitpos;
4963 /* From the start of a possibly ongoing outer byte buffer, offsets to
4964 the first bit of this element and to the first bit past the end of
4965 this element. */
4966 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
4967 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
4969 local->last_relative_index = relative_index;
4971 if (local->val == NULL_TREE)
4972 local->val = integer_zero_node;
4974 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
4975 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
4976 local->val = TREE_OPERAND (local->val, 0);
4978 if (TREE_CODE (local->val) != INTEGER_CST
4979 && TREE_CODE (local->val) != CONSTRUCTOR)
4981 error ("invalid initial value for member %qE", DECL_NAME (local->field));
4982 return;
4985 /* If this field does not start in this (or next) byte, skip some bytes. */
4986 if (next_offset / BITS_PER_UNIT != local->total_bytes)
4988 /* Output remnant of any bit field in previous bytes. */
4989 if (local->byte_buffer_in_use)
4991 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4992 local->total_bytes++;
4993 local->byte_buffer_in_use = false;
4996 /* If still not at proper byte, advance to there. */
4997 if (next_offset / BITS_PER_UNIT != local->total_bytes)
4999 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
5000 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
5001 local->total_bytes = next_offset / BITS_PER_UNIT;
5005 /* Set up the buffer if necessary. */
5006 if (!local->byte_buffer_in_use)
5008 local->byte = 0;
5009 if (ebitsize > 0)
5010 local->byte_buffer_in_use = true;
5013 /* If this is nested constructor, recurse passing the bit offset and the
5014 pending data, then retrieve the new pending data afterwards. */
5015 if (TREE_CODE (local->val) == CONSTRUCTOR)
5017 oc_outer_state temp_state;
5018 temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5019 temp_state.byte = local->byte;
5020 local->total_bytes
5021 += output_constructor (local->val, 0, 0, &temp_state);
5022 local->byte = temp_state.byte;
5023 return;
5026 /* Otherwise, we must split the element into pieces that fall within
5027 separate bytes, and combine each byte with previous or following
5028 bit-fields. */
5029 while (next_offset < end_offset)
5031 int this_time;
5032 int shift;
5033 HOST_WIDE_INT value;
5034 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5035 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5037 /* Advance from byte to byte within this element when necessary. */
5038 while (next_byte != local->total_bytes)
5040 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5041 local->total_bytes++;
5042 local->byte = 0;
5045 /* Number of bits we can process at once (all part of the same byte). */
5046 this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5047 if (BYTES_BIG_ENDIAN)
5049 /* On big-endian machine, take the most significant bits (of the
5050 bits that are significant) first and put them into bytes from
5051 the most significant end. */
5052 shift = end_offset - next_offset - this_time;
5054 /* Don't try to take a bunch of bits that cross
5055 the word boundary in the INTEGER_CST. We can
5056 only select bits from one element. */
5057 if ((shift / HOST_BITS_PER_WIDE_INT)
5058 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5060 const int end = shift + this_time - 1;
5061 shift = end & -HOST_BITS_PER_WIDE_INT;
5062 this_time = end - shift + 1;
5065 /* Now get the bits from the appropriate constant word. */
5066 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5067 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5069 /* Get the result. This works only when:
5070 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5071 local->byte |= (((value >> shift)
5072 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5073 << (BITS_PER_UNIT - this_time - next_bit));
5075 else
5077 /* On little-endian machines, take the least significant bits of
5078 the value first and pack them starting at the least significant
5079 bits of the bytes. */
5080 shift = next_offset - byte_relative_ebitpos;
5082 /* Don't try to take a bunch of bits that cross
5083 the word boundary in the INTEGER_CST. We can
5084 only select bits from one element. */
5085 if ((shift / HOST_BITS_PER_WIDE_INT)
5086 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5087 this_time
5088 = HOST_BITS_PER_WIDE_INT - (shift & (HOST_BITS_PER_WIDE_INT - 1));
5090 /* Now get the bits from the appropriate constant word. */
5091 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5092 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5094 /* Get the result. This works only when:
5095 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5096 local->byte |= (((value >> shift)
5097 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5098 << next_bit);
5101 next_offset += this_time;
5102 local->byte_buffer_in_use = true;
5106 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5107 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5108 caller output state of relevance in recursive invocations. */
5110 static unsigned HOST_WIDE_INT
5111 output_constructor (tree exp, unsigned HOST_WIDE_INT size,
5112 unsigned int align, oc_outer_state *outer)
5114 unsigned HOST_WIDE_INT cnt;
5115 constructor_elt *ce;
5117 oc_local_state local;
5119 /* Setup our local state to communicate with helpers. */
5120 local.exp = exp;
5121 local.type = TREE_TYPE (exp);
5122 local.size = size;
5123 local.align = align;
5124 if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5125 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5126 else
5127 local.min_index = NULL_TREE;
5129 local.total_bytes = 0;
5130 local.byte_buffer_in_use = outer != NULL;
5131 local.byte = outer ? outer->byte : 0;
5132 local.last_relative_index = -1;
5134 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5136 /* As CE goes through the elements of the constant, FIELD goes through the
5137 structure fields if the constant is a structure. If the constant is a
5138 union, we override this by getting the field from the TREE_LIST element.
5139 But the constant could also be an array. Then FIELD is zero.
5141 There is always a maximum of one element in the chain LINK for unions
5142 (even if the initializer in a source program incorrectly contains
5143 more one). */
5145 if (TREE_CODE (local.type) == RECORD_TYPE)
5146 local.field = TYPE_FIELDS (local.type);
5147 else
5148 local.field = NULL_TREE;
5150 for (cnt = 0;
5151 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5152 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5154 local.val = ce->value;
5155 local.index = NULL_TREE;
5157 /* The element in a union constructor specifies the proper field
5158 or index. */
5159 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5160 local.field = ce->index;
5162 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5163 local.index = ce->index;
5165 if (local.field && flag_verbose_asm)
5166 fprintf (asm_out_file, "%s %s:\n",
5167 ASM_COMMENT_START,
5168 DECL_NAME (local.field)
5169 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5170 : "<anonymous>");
5172 /* Eliminate the marker that makes a cast not be an lvalue. */
5173 if (local.val != NULL_TREE)
5174 STRIP_NOPS (local.val);
5176 /* Output the current element, using the appropriate helper ... */
5178 /* For an array slice not part of an outer bitfield. */
5179 if (!outer
5180 && local.index != NULL_TREE
5181 && TREE_CODE (local.index) == RANGE_EXPR)
5182 output_constructor_array_range (&local);
5184 /* For a field that is neither a true bitfield nor part of an outer one,
5185 known to be at least byte aligned and multiple-of-bytes long. */
5186 else if (!outer
5187 && (local.field == NULL_TREE
5188 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5189 output_constructor_regular_field (&local);
5191 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5192 supported for scalar fields, so we may need to convert first. */
5193 else
5195 if (TREE_CODE (local.val) == REAL_CST)
5196 local.val
5197 = fold_unary (VIEW_CONVERT_EXPR,
5198 build_nonstandard_integer_type
5199 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5200 local.val);
5201 output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5205 /* If we are not at toplevel, save the pending data for our caller.
5206 Otherwise output the pending data and padding zeros as needed. */
5207 if (outer)
5208 outer->byte = local.byte;
5209 else
5211 if (local.byte_buffer_in_use)
5213 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5214 local.total_bytes++;
5217 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5219 assemble_zeros (local.size - local.total_bytes);
5220 local.total_bytes = local.size;
5224 return local.total_bytes;
5227 /* Mark DECL as weak. */
5229 static void
5230 mark_weak (tree decl)
5232 DECL_WEAK (decl) = 1;
5234 if (DECL_RTL_SET_P (decl)
5235 && MEM_P (DECL_RTL (decl))
5236 && XEXP (DECL_RTL (decl), 0)
5237 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5238 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5241 /* Merge weak status between NEWDECL and OLDDECL. */
5243 void
5244 merge_weak (tree newdecl, tree olddecl)
5246 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5248 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5250 tree *pwd;
5251 /* We put the NEWDECL on the weak_decls list at some point
5252 and OLDDECL as well. Keep just OLDDECL on the list. */
5253 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5254 if (TREE_VALUE (*pwd) == newdecl)
5256 *pwd = TREE_CHAIN (*pwd);
5257 break;
5260 return;
5263 if (DECL_WEAK (newdecl))
5265 tree wd;
5267 /* NEWDECL is weak, but OLDDECL is not. */
5269 /* If we already output the OLDDECL, we're in trouble; we can't
5270 go back and make it weak. This should never happen in
5271 unit-at-a-time compilation. */
5272 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5274 /* If we've already generated rtl referencing OLDDECL, we may
5275 have done so in a way that will not function properly with
5276 a weak symbol. Again in unit-at-a-time this should be
5277 impossible. */
5278 gcc_assert (!TREE_USED (olddecl)
5279 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5281 if (TARGET_SUPPORTS_WEAK)
5283 /* We put the NEWDECL on the weak_decls list at some point.
5284 Replace it with the OLDDECL. */
5285 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5286 if (TREE_VALUE (wd) == newdecl)
5288 TREE_VALUE (wd) = olddecl;
5289 break;
5291 /* We may not find the entry on the list. If NEWDECL is a
5292 weak alias, then we will have already called
5293 globalize_decl to remove the entry; in that case, we do
5294 not need to do anything. */
5297 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5298 mark_weak (olddecl);
5300 else
5301 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5302 weak. Just update NEWDECL to indicate that it's weak too. */
5303 mark_weak (newdecl);
5306 /* Declare DECL to be a weak symbol. */
5308 void
5309 declare_weak (tree decl)
5311 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5312 if (! TREE_PUBLIC (decl))
5313 error ("weak declaration of %q+D must be public", decl);
5314 else if (!TARGET_SUPPORTS_WEAK)
5315 warning (0, "weak declaration of %q+D not supported", decl);
5317 mark_weak (decl);
5318 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5319 DECL_ATTRIBUTES (decl)
5320 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5323 static void
5324 weak_finish_1 (tree decl)
5326 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5327 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5328 #endif
5330 if (! TREE_USED (decl))
5331 return;
5333 #ifdef ASM_WEAKEN_DECL
5334 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5335 #else
5336 #ifdef ASM_WEAKEN_LABEL
5337 ASM_WEAKEN_LABEL (asm_out_file, name);
5338 #else
5339 #ifdef ASM_OUTPUT_WEAK_ALIAS
5341 static bool warn_once = 0;
5342 if (! warn_once)
5344 warning (0, "only weak aliases are supported in this configuration");
5345 warn_once = 1;
5347 return;
5349 #endif
5350 #endif
5351 #endif
5354 /* Fiven an assembly name, find the decl it is associated with. */
5355 static tree
5356 find_decl (tree target)
5358 symtab_node *node = symtab_node::get_for_asmname (target);
5359 if (node)
5360 return node->decl;
5361 return NULL_TREE;
5364 /* This TREE_LIST contains weakref targets. */
5366 static GTY(()) tree weakref_targets;
5368 /* Emit any pending weak declarations. */
5370 void
5371 weak_finish (void)
5373 tree t;
5375 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5377 tree alias_decl = TREE_PURPOSE (t);
5378 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5380 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5381 /* Remove alias_decl from the weak list, but leave entries for
5382 the target alone. */
5383 target = NULL_TREE;
5384 #ifndef ASM_OUTPUT_WEAKREF
5385 else if (! TREE_SYMBOL_REFERENCED (target))
5387 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5388 defined, otherwise we and weak_finish_1 would use
5389 different macros. */
5390 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5391 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5392 # else
5393 tree decl = find_decl (target);
5395 if (! decl)
5397 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5398 TREE_CODE (alias_decl), target,
5399 TREE_TYPE (alias_decl));
5401 DECL_EXTERNAL (decl) = 1;
5402 TREE_PUBLIC (decl) = 1;
5403 DECL_ARTIFICIAL (decl) = 1;
5404 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5405 TREE_USED (decl) = 1;
5408 weak_finish_1 (decl);
5409 # endif
5411 #endif
5414 tree *p;
5415 tree t2;
5417 /* Remove the alias and the target from the pending weak list
5418 so that we do not emit any .weak directives for the former,
5419 nor multiple .weak directives for the latter. */
5420 for (p = &weak_decls; (t2 = *p) ; )
5422 if (TREE_VALUE (t2) == alias_decl
5423 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5424 *p = TREE_CHAIN (t2);
5425 else
5426 p = &TREE_CHAIN (t2);
5429 /* Remove other weakrefs to the same target, to speed things up. */
5430 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5432 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5433 *p = TREE_CHAIN (t2);
5434 else
5435 p = &TREE_CHAIN (t2);
5440 for (t = weak_decls; t; t = TREE_CHAIN (t))
5442 tree decl = TREE_VALUE (t);
5444 weak_finish_1 (decl);
5448 /* Emit the assembly bits to indicate that DECL is globally visible. */
5450 static void
5451 globalize_decl (tree decl)
5454 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5455 if (DECL_WEAK (decl))
5457 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5458 tree *p, t;
5460 #ifdef ASM_WEAKEN_DECL
5461 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5462 #else
5463 ASM_WEAKEN_LABEL (asm_out_file, name);
5464 #endif
5466 /* Remove this function from the pending weak list so that
5467 we do not emit multiple .weak directives for it. */
5468 for (p = &weak_decls; (t = *p) ; )
5470 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5471 *p = TREE_CHAIN (t);
5472 else
5473 p = &TREE_CHAIN (t);
5476 /* Remove weakrefs to the same target from the pending weakref
5477 list, for the same reason. */
5478 for (p = &weakref_targets; (t = *p) ; )
5480 if (DECL_ASSEMBLER_NAME (decl)
5481 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5482 *p = TREE_CHAIN (t);
5483 else
5484 p = &TREE_CHAIN (t);
5487 return;
5489 #endif
5491 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5494 vec<alias_pair, va_gc> *alias_pairs;
5496 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5497 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5498 tree node is DECL to have the value of the tree node TARGET. */
5500 void
5501 do_assemble_alias (tree decl, tree target)
5503 /* Emulated TLS had better not get this var. */
5504 gcc_assert (!(!targetm.have_tls
5505 && TREE_CODE (decl) == VAR_DECL
5506 && DECL_THREAD_LOCAL_P (decl)));
5508 if (TREE_ASM_WRITTEN (decl))
5509 return;
5511 /* We must force creation of DECL_RTL for debug info generation, even though
5512 we don't use it here. */
5513 make_decl_rtl (decl);
5515 TREE_ASM_WRITTEN (decl) = 1;
5516 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5518 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5520 ultimate_transparent_alias_target (&target);
5522 if (!TREE_SYMBOL_REFERENCED (target))
5523 weakref_targets = tree_cons (decl, target, weakref_targets);
5525 #ifdef ASM_OUTPUT_WEAKREF
5526 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5527 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5528 IDENTIFIER_POINTER (target));
5529 #else
5530 if (!TARGET_SUPPORTS_WEAK)
5532 error_at (DECL_SOURCE_LOCATION (decl),
5533 "weakref is not supported in this configuration");
5534 return;
5536 #endif
5537 return;
5540 #ifdef ASM_OUTPUT_DEF
5541 /* Make name accessible from other files, if appropriate. */
5543 if (TREE_PUBLIC (decl))
5545 globalize_decl (decl);
5546 maybe_assemble_visibility (decl);
5548 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5550 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5551 if (targetm.has_ifunc_p ())
5552 ASM_OUTPUT_TYPE_DIRECTIVE
5553 (asm_out_file, IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5554 IFUNC_ASM_TYPE);
5555 else
5556 #endif
5557 error_at (DECL_SOURCE_LOCATION (decl),
5558 "ifunc is not supported on this target");
5561 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5562 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5563 # else
5564 ASM_OUTPUT_DEF (asm_out_file,
5565 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5566 IDENTIFIER_POINTER (target));
5567 # endif
5568 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5570 const char *name;
5571 tree *p, t;
5573 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5574 # ifdef ASM_WEAKEN_DECL
5575 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5576 # else
5577 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5578 # endif
5579 /* Remove this function from the pending weak list so that
5580 we do not emit multiple .weak directives for it. */
5581 for (p = &weak_decls; (t = *p) ; )
5582 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5583 *p = TREE_CHAIN (t);
5584 else
5585 p = &TREE_CHAIN (t);
5587 /* Remove weakrefs to the same target from the pending weakref
5588 list, for the same reason. */
5589 for (p = &weakref_targets; (t = *p) ; )
5591 if (DECL_ASSEMBLER_NAME (decl)
5592 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5593 *p = TREE_CHAIN (t);
5594 else
5595 p = &TREE_CHAIN (t);
5598 #endif
5601 /* Emit an assembler directive to make the symbol for DECL an alias to
5602 the symbol for TARGET. */
5604 void
5605 assemble_alias (tree decl, tree target)
5607 tree target_decl;
5609 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5611 tree alias = DECL_ASSEMBLER_NAME (decl);
5613 ultimate_transparent_alias_target (&target);
5615 if (alias == target)
5616 error ("weakref %q+D ultimately targets itself", decl);
5617 if (TREE_PUBLIC (decl))
5618 error ("weakref %q+D must have static linkage", decl);
5620 else
5622 #if !defined (ASM_OUTPUT_DEF)
5623 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5624 error_at (DECL_SOURCE_LOCATION (decl),
5625 "alias definitions not supported in this configuration");
5626 TREE_ASM_WRITTEN (decl) = 1;
5627 return;
5628 # else
5629 if (!DECL_WEAK (decl))
5631 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5632 error_at (DECL_SOURCE_LOCATION (decl),
5633 "ifunc is not supported in this configuration");
5634 else
5635 error_at (DECL_SOURCE_LOCATION (decl),
5636 "only weak aliases are supported in this configuration");
5637 TREE_ASM_WRITTEN (decl) = 1;
5638 return;
5640 # endif
5641 #endif
5643 TREE_USED (decl) = 1;
5645 /* Allow aliases to aliases. */
5646 if (TREE_CODE (decl) == FUNCTION_DECL)
5647 cgraph_node::get_create (decl)->alias = true;
5648 else
5649 varpool_node::get_create (decl)->alias = true;
5651 /* If the target has already been emitted, we don't have to queue the
5652 alias. This saves a tad of memory. */
5653 if (symtab->global_info_ready)
5654 target_decl = find_decl (target);
5655 else
5656 target_decl= NULL;
5657 if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5658 || symtab->state >= EXPANSION)
5659 do_assemble_alias (decl, target);
5660 else
5662 alias_pair p = {decl, target};
5663 vec_safe_push (alias_pairs, p);
5667 /* Record and output a table of translations from original function
5668 to its transaction aware clone. Note that tm_pure functions are
5669 considered to be their own clone. */
5671 static GTY((if_marked ("tree_map_marked_p"), param_is (struct tree_map)))
5672 htab_t tm_clone_hash;
5674 void
5675 record_tm_clone_pair (tree o, tree n)
5677 struct tree_map **slot, *h;
5679 if (tm_clone_hash == NULL)
5680 tm_clone_hash = htab_create_ggc (32, tree_map_hash, tree_map_eq, 0);
5682 h = ggc_alloc<tree_map> ();
5683 h->hash = htab_hash_pointer (o);
5684 h->base.from = o;
5685 h->to = n;
5687 slot = (struct tree_map **)
5688 htab_find_slot_with_hash (tm_clone_hash, h, h->hash, INSERT);
5689 *slot = h;
5692 tree
5693 get_tm_clone_pair (tree o)
5695 if (tm_clone_hash)
5697 struct tree_map *h, in;
5699 in.base.from = o;
5700 in.hash = htab_hash_pointer (o);
5701 h = (struct tree_map *) htab_find_with_hash (tm_clone_hash,
5702 &in, in.hash);
5703 if (h)
5704 return h->to;
5706 return NULL_TREE;
5709 typedef struct tm_alias_pair
5711 unsigned int uid;
5712 tree from;
5713 tree to;
5714 } tm_alias_pair;
5717 /* Helper function for finish_tm_clone_pairs. Dump a hash table entry
5718 into a VEC in INFO. */
5720 static int
5721 dump_tm_clone_to_vec (void **slot, void *info)
5723 struct tree_map *map = (struct tree_map *) *slot;
5724 vec<tm_alias_pair> *tm_alias_pairs = (vec<tm_alias_pair> *) info;
5725 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
5726 tm_alias_pairs->safe_push (p);
5727 return 1;
5730 /* Dump the actual pairs to the .tm_clone_table section. */
5732 static void
5733 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
5735 unsigned i;
5736 tm_alias_pair *p;
5737 bool switched = false;
5739 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
5741 tree src = p->from;
5742 tree dst = p->to;
5743 struct cgraph_node *src_n = cgraph_node::get (src);
5744 struct cgraph_node *dst_n = cgraph_node::get (dst);
5746 /* The function ipa_tm_create_version() marks the clone as needed if
5747 the original function was needed. But we also mark the clone as
5748 needed if we ever called the clone indirectly through
5749 TM_GETTMCLONE. If neither of these are true, we didn't generate
5750 a clone, and we didn't call it indirectly... no sense keeping it
5751 in the clone table. */
5752 if (!dst_n || !dst_n->definition)
5753 continue;
5755 /* This covers the case where we have optimized the original
5756 function away, and only access the transactional clone. */
5757 if (!src_n || !src_n->definition)
5758 continue;
5760 if (!switched)
5762 switch_to_section (targetm.asm_out.tm_clone_table_section ());
5763 assemble_align (POINTER_SIZE);
5764 switched = true;
5767 assemble_integer (XEXP (DECL_RTL (src), 0),
5768 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
5769 assemble_integer (XEXP (DECL_RTL (dst), 0),
5770 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
5774 /* Provide a default for the tm_clone_table section. */
5776 section *
5777 default_clone_table_section (void)
5779 return get_named_section (NULL, ".tm_clone_table", 3);
5782 /* Helper comparison function for qsorting by the DECL_UID stored in
5783 alias_pair->emitted_diags. */
5785 static int
5786 tm_alias_pair_cmp (const void *x, const void *y)
5788 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
5789 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
5790 if (p1->uid < p2->uid)
5791 return -1;
5792 if (p1->uid > p2->uid)
5793 return 1;
5794 return 0;
5797 void
5798 finish_tm_clone_pairs (void)
5800 vec<tm_alias_pair> tm_alias_pairs = vNULL;
5802 if (tm_clone_hash == NULL)
5803 return;
5805 /* We need a determenistic order for the .tm_clone_table, otherwise
5806 we will get bootstrap comparison failures, so dump the hash table
5807 to a vector, sort it, and dump the vector. */
5809 /* Dump the hashtable to a vector. */
5810 htab_traverse_noresize (tm_clone_hash, dump_tm_clone_to_vec,
5811 (void *) &tm_alias_pairs);
5812 /* Sort it. */
5813 tm_alias_pairs.qsort (tm_alias_pair_cmp);
5815 /* Dump it. */
5816 dump_tm_clone_pairs (tm_alias_pairs);
5818 htab_delete (tm_clone_hash);
5819 tm_clone_hash = NULL;
5820 tm_alias_pairs.release ();
5824 /* Emit an assembler directive to set symbol for DECL visibility to
5825 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
5827 void
5828 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
5829 int vis ATTRIBUTE_UNUSED)
5831 #ifdef HAVE_GAS_HIDDEN
5832 static const char * const visibility_types[] = {
5833 NULL, "protected", "hidden", "internal"
5836 const char *name, *type;
5838 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5839 type = visibility_types[vis];
5841 fprintf (asm_out_file, "\t.%s\t", type);
5842 assemble_name (asm_out_file, name);
5843 fprintf (asm_out_file, "\n");
5844 #else
5845 if (!DECL_ARTIFICIAL (decl))
5846 warning (OPT_Wattributes, "visibility attribute not supported "
5847 "in this configuration; ignored");
5848 #endif
5851 /* A helper function to call assemble_visibility when needed for a decl. */
5854 maybe_assemble_visibility (tree decl)
5856 enum symbol_visibility vis = DECL_VISIBILITY (decl);
5858 if (vis != VISIBILITY_DEFAULT)
5860 targetm.asm_out.assemble_visibility (decl, vis);
5861 return 1;
5863 else
5864 return 0;
5867 /* Returns 1 if the target configuration supports defining public symbols
5868 so that one of them will be chosen at link time instead of generating a
5869 multiply-defined symbol error, whether through the use of weak symbols or
5870 a target-specific mechanism for having duplicates discarded. */
5873 supports_one_only (void)
5875 if (SUPPORTS_ONE_ONLY)
5876 return 1;
5877 return TARGET_SUPPORTS_WEAK;
5880 /* Set up DECL as a public symbol that can be defined in multiple
5881 translation units without generating a linker error. */
5883 void
5884 make_decl_one_only (tree decl, tree comdat_group)
5886 struct symtab_node *symbol;
5887 gcc_assert (TREE_CODE (decl) == VAR_DECL
5888 || TREE_CODE (decl) == FUNCTION_DECL);
5890 TREE_PUBLIC (decl) = 1;
5892 if (TREE_CODE (decl) == VAR_DECL)
5893 symbol = varpool_node::get_create (decl);
5894 else
5895 symbol = cgraph_node::get_create (decl);
5897 if (SUPPORTS_ONE_ONLY)
5899 #ifdef MAKE_DECL_ONE_ONLY
5900 MAKE_DECL_ONE_ONLY (decl);
5901 #endif
5902 symbol->set_comdat_group (comdat_group);
5904 else if (TREE_CODE (decl) == VAR_DECL
5905 && (DECL_INITIAL (decl) == 0
5906 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
5907 DECL_COMMON (decl) = 1;
5908 else
5910 gcc_assert (TARGET_SUPPORTS_WEAK);
5911 DECL_WEAK (decl) = 1;
5915 void
5916 init_varasm_once (void)
5918 section_htab = htab_create_ggc (31, section_entry_hash,
5919 section_entry_eq, NULL);
5920 object_block_htab = htab_create_ggc (31, object_block_entry_hash,
5921 object_block_entry_eq, NULL);
5922 const_desc_htab = htab_create_ggc (1009, const_desc_hash,
5923 const_desc_eq, NULL);
5925 const_alias_set = new_alias_set ();
5926 shared_constant_pool = create_constant_pool ();
5928 #ifdef TEXT_SECTION_ASM_OP
5929 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
5930 TEXT_SECTION_ASM_OP);
5931 #endif
5933 #ifdef DATA_SECTION_ASM_OP
5934 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5935 DATA_SECTION_ASM_OP);
5936 #endif
5938 #ifdef SDATA_SECTION_ASM_OP
5939 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5940 SDATA_SECTION_ASM_OP);
5941 #endif
5943 #ifdef READONLY_DATA_SECTION_ASM_OP
5944 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
5945 READONLY_DATA_SECTION_ASM_OP);
5946 #endif
5948 #ifdef CTORS_SECTION_ASM_OP
5949 ctors_section = get_unnamed_section (0, output_section_asm_op,
5950 CTORS_SECTION_ASM_OP);
5951 #endif
5953 #ifdef DTORS_SECTION_ASM_OP
5954 dtors_section = get_unnamed_section (0, output_section_asm_op,
5955 DTORS_SECTION_ASM_OP);
5956 #endif
5958 #ifdef BSS_SECTION_ASM_OP
5959 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5960 output_section_asm_op,
5961 BSS_SECTION_ASM_OP);
5962 #endif
5964 #ifdef SBSS_SECTION_ASM_OP
5965 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5966 output_section_asm_op,
5967 SBSS_SECTION_ASM_OP);
5968 #endif
5970 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5971 | SECTION_COMMON, emit_tls_common);
5972 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5973 | SECTION_COMMON, emit_local);
5974 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5975 | SECTION_COMMON, emit_common);
5977 #if defined ASM_OUTPUT_ALIGNED_BSS
5978 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
5979 emit_bss);
5980 #endif
5982 targetm.asm_out.init_sections ();
5984 if (readonly_data_section == NULL)
5985 readonly_data_section = text_section;
5987 #ifdef ASM_OUTPUT_EXTERNAL
5988 pending_assemble_externals_set = new hash_set<tree>;
5989 #endif
5992 enum tls_model
5993 decl_default_tls_model (const_tree decl)
5995 enum tls_model kind;
5996 bool is_local;
5998 is_local = targetm.binds_local_p (decl);
5999 if (!flag_shlib)
6001 if (is_local)
6002 kind = TLS_MODEL_LOCAL_EXEC;
6003 else
6004 kind = TLS_MODEL_INITIAL_EXEC;
6007 /* Local dynamic is inefficient when we're not combining the
6008 parts of the address. */
6009 else if (optimize && is_local)
6010 kind = TLS_MODEL_LOCAL_DYNAMIC;
6011 else
6012 kind = TLS_MODEL_GLOBAL_DYNAMIC;
6013 if (kind < flag_tls_default)
6014 kind = flag_tls_default;
6016 return kind;
6019 /* Select a set of attributes for section NAME based on the properties
6020 of DECL and whether or not RELOC indicates that DECL's initializer
6021 might contain runtime relocations.
6023 We make the section read-only and executable for a function decl,
6024 read-only for a const data decl, and writable for a non-const data decl. */
6026 unsigned int
6027 default_section_type_flags (tree decl, const char *name, int reloc)
6029 unsigned int flags;
6031 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6032 flags = SECTION_CODE;
6033 else if (decl)
6035 enum section_category category
6036 = categorize_decl_for_section (decl, reloc);
6037 if (decl_readonly_section_1 (category))
6038 flags = 0;
6039 else if (category == SECCAT_DATA_REL_RO
6040 || category == SECCAT_DATA_REL_RO_LOCAL)
6041 flags = SECTION_WRITE | SECTION_RELRO;
6042 else
6043 flags = SECTION_WRITE;
6045 else
6047 flags = SECTION_WRITE;
6048 if (strcmp (name, ".data.rel.ro") == 0
6049 || strcmp (name, ".data.rel.ro.local") == 0)
6050 flags |= SECTION_RELRO;
6053 if (decl && DECL_P (decl) && DECL_COMDAT_GROUP (decl))
6054 flags |= SECTION_LINKONCE;
6056 if (strcmp (name, ".vtable_map_vars") == 0)
6057 flags |= SECTION_LINKONCE;
6059 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6060 flags |= SECTION_TLS | SECTION_WRITE;
6062 if (strcmp (name, ".bss") == 0
6063 || strncmp (name, ".bss.", 5) == 0
6064 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6065 || strcmp (name, ".sbss") == 0
6066 || strncmp (name, ".sbss.", 6) == 0
6067 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6068 flags |= SECTION_BSS;
6070 if (strcmp (name, ".tdata") == 0
6071 || strncmp (name, ".tdata.", 7) == 0
6072 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6073 flags |= SECTION_TLS;
6075 if (strcmp (name, ".tbss") == 0
6076 || strncmp (name, ".tbss.", 6) == 0
6077 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6078 flags |= SECTION_TLS | SECTION_BSS;
6080 /* These three sections have special ELF types. They are neither
6081 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
6082 want to print a section type (@progbits or @nobits). If someone
6083 is silly enough to emit code or TLS variables to one of these
6084 sections, then don't handle them specially. */
6085 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6086 && (strcmp (name, ".init_array") == 0
6087 || strcmp (name, ".fini_array") == 0
6088 || strcmp (name, ".preinit_array") == 0))
6089 flags |= SECTION_NOTYPE;
6091 #ifdef UPC_SHARED_SECTION_NAME
6092 /* The UPC shared section is not loaded into memory.
6093 It is used only to layout shared veriables. */
6094 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6095 && (strcmp (name, UPC_SHARED_SECTION_NAME) == 0))
6097 flags |= SECTION_BSS;
6098 # ifdef HAVE_UPC_LINK_SCRIPT
6099 flags = SECTION_DEBUG | (flags & ~SECTION_WRITE);
6100 # endif
6102 #endif
6104 return flags;
6107 /* Return true if the target supports some form of global BSS,
6108 either through bss_noswitch_section, or by selecting a BSS
6109 section in TARGET_ASM_SELECT_SECTION. */
6111 bool
6112 have_global_bss_p (void)
6114 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6117 /* Output assembly to switch to section NAME with attribute FLAGS.
6118 Four variants for common object file formats. */
6120 void
6121 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6122 unsigned int flags ATTRIBUTE_UNUSED,
6123 tree decl ATTRIBUTE_UNUSED)
6125 /* Some object formats don't support named sections at all. The
6126 front-end should already have flagged this as an error. */
6127 gcc_unreachable ();
6130 #ifndef TLS_SECTION_ASM_FLAG
6131 #define TLS_SECTION_ASM_FLAG 'T'
6132 #endif
6134 void
6135 default_elf_asm_named_section (const char *name, unsigned int flags,
6136 tree decl ATTRIBUTE_UNUSED)
6138 char flagchars[10], *f = flagchars;
6140 /* If we have already declared this section, we can use an
6141 abbreviated form to switch back to it -- unless this section is
6142 part of a COMDAT groups, in which case GAS requires the full
6143 declaration every time. */
6144 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6145 && (flags & SECTION_DECLARED))
6147 fprintf (asm_out_file, "\t.section\t%s\n", name);
6148 return;
6151 if (!(flags & SECTION_DEBUG))
6152 *f++ = 'a';
6153 if (flags & SECTION_EXCLUDE)
6154 *f++ = 'e';
6155 if (flags & SECTION_WRITE)
6156 *f++ = 'w';
6157 if (flags & SECTION_CODE)
6158 *f++ = 'x';
6159 if (flags & SECTION_SMALL)
6160 *f++ = 's';
6161 if (flags & SECTION_MERGE)
6162 *f++ = 'M';
6163 if (flags & SECTION_STRINGS)
6164 *f++ = 'S';
6165 if (flags & SECTION_TLS)
6166 *f++ = TLS_SECTION_ASM_FLAG;
6167 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6168 *f++ = 'G';
6169 *f = '\0';
6171 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6173 if (!(flags & SECTION_NOTYPE))
6175 const char *type;
6176 const char *format;
6178 if (flags & SECTION_BSS)
6179 type = "nobits";
6180 else
6181 type = "progbits";
6183 format = ",@%s";
6184 /* On platforms that use "@" as the assembly comment character,
6185 use "%" instead. */
6186 if (strcmp (ASM_COMMENT_START, "@") == 0)
6187 format = ",%%%s";
6188 fprintf (asm_out_file, format, type);
6190 if (flags & SECTION_ENTSIZE)
6191 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6192 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6194 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6195 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6196 else
6197 fprintf (asm_out_file, ",%s,comdat",
6198 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6202 putc ('\n', asm_out_file);
6205 void
6206 default_coff_asm_named_section (const char *name, unsigned int flags,
6207 tree decl ATTRIBUTE_UNUSED)
6209 char flagchars[8], *f = flagchars;
6211 if (flags & SECTION_WRITE)
6212 *f++ = 'w';
6213 if (flags & SECTION_CODE)
6214 *f++ = 'x';
6215 *f = '\0';
6217 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6220 void
6221 default_pe_asm_named_section (const char *name, unsigned int flags,
6222 tree decl)
6224 default_coff_asm_named_section (name, flags, decl);
6226 if (flags & SECTION_LINKONCE)
6228 /* Functions may have been compiled at various levels of
6229 optimization so we can't use `same_size' here.
6230 Instead, have the linker pick one. */
6231 fprintf (asm_out_file, "\t.linkonce %s\n",
6232 (flags & SECTION_CODE ? "discard" : "same_size"));
6236 /* The lame default section selector. */
6238 section *
6239 default_select_section (tree decl, int reloc,
6240 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6242 if (DECL_P (decl))
6244 if (decl_readonly_section (decl, reloc))
6245 return readonly_data_section;
6247 else if (TREE_CODE (decl) == CONSTRUCTOR)
6249 if (! ((flag_pic && reloc)
6250 || !TREE_READONLY (decl)
6251 || TREE_SIDE_EFFECTS (decl)
6252 || !TREE_CONSTANT (decl)))
6253 return readonly_data_section;
6255 else if (TREE_CODE (decl) == STRING_CST)
6256 return readonly_data_section;
6257 else if (! (flag_pic && reloc))
6258 return readonly_data_section;
6260 return data_section;
6263 enum section_category
6264 categorize_decl_for_section (const_tree decl, int reloc)
6266 enum section_category ret;
6268 if (TREE_CODE (decl) == FUNCTION_DECL)
6269 return SECCAT_TEXT;
6270 else if (TREE_CODE (decl) == STRING_CST)
6272 if ((flag_sanitize & SANITIZE_ADDRESS)
6273 && asan_protect_global (CONST_CAST_TREE (decl)))
6274 /* or !flag_merge_constants */
6275 return SECCAT_RODATA;
6276 else
6277 return SECCAT_RODATA_MERGE_STR;
6279 else if (TREE_CODE (decl) == VAR_DECL)
6281 if (bss_initializer_p (decl))
6282 ret = SECCAT_BSS;
6283 else if (! TREE_READONLY (decl)
6284 || TREE_SIDE_EFFECTS (decl)
6285 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
6287 /* Here the reloc_rw_mask is not testing whether the section should
6288 be read-only or not, but whether the dynamic link will have to
6289 do something. If so, we wish to segregate the data in order to
6290 minimize cache misses inside the dynamic linker. */
6291 if (reloc & targetm.asm_out.reloc_rw_mask ())
6292 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6293 else
6294 ret = SECCAT_DATA;
6296 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6297 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6298 else if (reloc || flag_merge_constants < 2
6299 || ((flag_sanitize & SANITIZE_ADDRESS)
6300 && asan_protect_global (CONST_CAST_TREE (decl))))
6301 /* C and C++ don't allow different variables to share the same
6302 location. -fmerge-all-constants allows even that (at the
6303 expense of not conforming). */
6304 ret = SECCAT_RODATA;
6305 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6306 ret = SECCAT_RODATA_MERGE_STR_INIT;
6307 else
6308 ret = SECCAT_RODATA_MERGE_CONST;
6310 else if (TREE_CODE (decl) == CONSTRUCTOR)
6312 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6313 || TREE_SIDE_EFFECTS (decl)
6314 || ! TREE_CONSTANT (decl))
6315 ret = SECCAT_DATA;
6316 else
6317 ret = SECCAT_RODATA;
6319 else
6320 ret = SECCAT_RODATA;
6322 /* There are no read-only thread-local sections. */
6323 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6325 /* Note that this would be *just* SECCAT_BSS, except that there's
6326 no concept of a read-only thread-local-data section. */
6327 if (ret == SECCAT_BSS
6328 || (flag_zero_initialized_in_bss
6329 && initializer_zerop (DECL_INITIAL (decl))))
6330 ret = SECCAT_TBSS;
6331 else
6332 ret = SECCAT_TDATA;
6335 /* If the target uses small data sections, select it. */
6336 else if (targetm.in_small_data_p (decl))
6338 if (ret == SECCAT_BSS)
6339 ret = SECCAT_SBSS;
6340 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6341 ret = SECCAT_SRODATA;
6342 else
6343 ret = SECCAT_SDATA;
6346 return ret;
6349 static bool
6350 decl_readonly_section_1 (enum section_category category)
6352 switch (category)
6354 case SECCAT_RODATA:
6355 case SECCAT_RODATA_MERGE_STR:
6356 case SECCAT_RODATA_MERGE_STR_INIT:
6357 case SECCAT_RODATA_MERGE_CONST:
6358 case SECCAT_SRODATA:
6359 return true;
6360 default:
6361 return false;
6365 bool
6366 decl_readonly_section (const_tree decl, int reloc)
6368 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6371 /* Select a section based on the above categorization. */
6373 section *
6374 default_elf_select_section (tree decl, int reloc,
6375 unsigned HOST_WIDE_INT align)
6377 const char *sname;
6378 switch (categorize_decl_for_section (decl, reloc))
6380 case SECCAT_TEXT:
6381 /* We're not supposed to be called on FUNCTION_DECLs. */
6382 gcc_unreachable ();
6383 case SECCAT_RODATA:
6384 return readonly_data_section;
6385 case SECCAT_RODATA_MERGE_STR:
6386 return mergeable_string_section (decl, align, 0);
6387 case SECCAT_RODATA_MERGE_STR_INIT:
6388 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6389 case SECCAT_RODATA_MERGE_CONST:
6390 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6391 case SECCAT_SRODATA:
6392 sname = ".sdata2";
6393 break;
6394 case SECCAT_DATA:
6395 return data_section;
6396 case SECCAT_DATA_REL:
6397 sname = ".data.rel";
6398 break;
6399 case SECCAT_DATA_REL_LOCAL:
6400 sname = ".data.rel.local";
6401 break;
6402 case SECCAT_DATA_REL_RO:
6403 sname = ".data.rel.ro";
6404 break;
6405 case SECCAT_DATA_REL_RO_LOCAL:
6406 sname = ".data.rel.ro.local";
6407 break;
6408 case SECCAT_SDATA:
6409 sname = ".sdata";
6410 break;
6411 case SECCAT_TDATA:
6412 sname = ".tdata";
6413 break;
6414 case SECCAT_BSS:
6415 if (bss_section)
6416 return bss_section;
6417 sname = ".bss";
6418 break;
6419 case SECCAT_SBSS:
6420 sname = ".sbss";
6421 break;
6422 case SECCAT_TBSS:
6423 sname = ".tbss";
6424 break;
6425 default:
6426 gcc_unreachable ();
6429 return get_named_section (decl, sname, reloc);
6432 /* Construct a unique section name based on the decl name and the
6433 categorization performed above. */
6435 void
6436 default_unique_section (tree decl, int reloc)
6438 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6439 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6440 const char *prefix, *name, *linkonce;
6441 char *string;
6443 switch (categorize_decl_for_section (decl, reloc))
6445 case SECCAT_TEXT:
6446 prefix = one_only ? ".t" : ".text";
6447 break;
6448 case SECCAT_RODATA:
6449 case SECCAT_RODATA_MERGE_STR:
6450 case SECCAT_RODATA_MERGE_STR_INIT:
6451 case SECCAT_RODATA_MERGE_CONST:
6452 prefix = one_only ? ".r" : ".rodata";
6453 break;
6454 case SECCAT_SRODATA:
6455 prefix = one_only ? ".s2" : ".sdata2";
6456 break;
6457 case SECCAT_DATA:
6458 prefix = one_only ? ".d" : ".data";
6459 break;
6460 case SECCAT_DATA_REL:
6461 prefix = one_only ? ".d.rel" : ".data.rel";
6462 break;
6463 case SECCAT_DATA_REL_LOCAL:
6464 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6465 break;
6466 case SECCAT_DATA_REL_RO:
6467 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6468 break;
6469 case SECCAT_DATA_REL_RO_LOCAL:
6470 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6471 break;
6472 case SECCAT_SDATA:
6473 prefix = one_only ? ".s" : ".sdata";
6474 break;
6475 case SECCAT_BSS:
6476 prefix = one_only ? ".b" : ".bss";
6477 break;
6478 case SECCAT_SBSS:
6479 prefix = one_only ? ".sb" : ".sbss";
6480 break;
6481 case SECCAT_TDATA:
6482 prefix = one_only ? ".td" : ".tdata";
6483 break;
6484 case SECCAT_TBSS:
6485 prefix = one_only ? ".tb" : ".tbss";
6486 break;
6487 default:
6488 gcc_unreachable ();
6491 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
6492 name = targetm.strip_name_encoding (name);
6494 /* If we're using one_only, then there needs to be a .gnu.linkonce
6495 prefix to the section name. */
6496 linkonce = one_only ? ".gnu.linkonce" : "";
6498 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6500 set_decl_section_name (decl, string);
6503 /* Subroutine of compute_reloc_for_rtx for leaf rtxes. */
6505 static int
6506 compute_reloc_for_rtx_1 (const_rtx x)
6508 switch (GET_CODE (x))
6510 case SYMBOL_REF:
6511 return SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6512 case LABEL_REF:
6513 return 1;
6514 default:
6515 return 0;
6519 /* Like compute_reloc_for_constant, except for an RTX. The return value
6520 is a mask for which bit 1 indicates a global relocation, and bit 0
6521 indicates a local relocation. */
6523 static int
6524 compute_reloc_for_rtx (const_rtx x)
6526 switch (GET_CODE (x))
6528 case SYMBOL_REF:
6529 case LABEL_REF:
6530 return compute_reloc_for_rtx_1 (x);
6532 case CONST:
6534 int reloc = 0;
6535 subrtx_iterator::array_type array;
6536 FOR_EACH_SUBRTX (iter, array, x, ALL)
6537 reloc |= compute_reloc_for_rtx_1 (*iter);
6538 return reloc;
6541 default:
6542 return 0;
6546 section *
6547 default_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
6548 rtx x,
6549 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6551 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6552 return data_section;
6553 else
6554 return readonly_data_section;
6557 section *
6558 default_elf_select_rtx_section (enum machine_mode mode, rtx x,
6559 unsigned HOST_WIDE_INT align)
6561 int reloc = compute_reloc_for_rtx (x);
6563 /* ??? Handle small data here somehow. */
6565 if (reloc & targetm.asm_out.reloc_rw_mask ())
6567 if (reloc == 1)
6568 return get_named_section (NULL, ".data.rel.ro.local", 1);
6569 else
6570 return get_named_section (NULL, ".data.rel.ro", 3);
6573 return mergeable_constant_section (mode, align, 0);
6576 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6578 void
6579 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6581 rtx symbol;
6582 int flags;
6584 /* Careful not to prod global register variables. */
6585 if (!MEM_P (rtl))
6586 return;
6587 symbol = XEXP (rtl, 0);
6588 if (GET_CODE (symbol) != SYMBOL_REF)
6589 return;
6591 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6592 if (TREE_CODE (decl) == FUNCTION_DECL)
6593 flags |= SYMBOL_FLAG_FUNCTION;
6594 if (targetm.binds_local_p (decl))
6595 flags |= SYMBOL_FLAG_LOCAL;
6596 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6597 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6598 else if (targetm.in_small_data_p (decl))
6599 flags |= SYMBOL_FLAG_SMALL;
6600 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6601 being PUBLIC, the thing *must* be defined in this translation unit.
6602 Prevent this buglet from being propagated into rtl code as well. */
6603 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6604 flags |= SYMBOL_FLAG_EXTERNAL;
6606 SYMBOL_REF_FLAGS (symbol) = flags;
6609 /* By default, we do nothing for encode_section_info, so we need not
6610 do anything but discard the '*' marker. */
6612 const char *
6613 default_strip_name_encoding (const char *str)
6615 return str + (*str == '*');
6618 #ifdef ASM_OUTPUT_DEF
6619 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6620 anchor relative to ".", the current section position. */
6622 void
6623 default_asm_output_anchor (rtx symbol)
6625 char buffer[100];
6627 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6628 SYMBOL_REF_BLOCK_OFFSET (symbol));
6629 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6631 #endif
6633 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6635 bool
6636 default_use_anchors_for_symbol_p (const_rtx symbol)
6638 section *sect;
6639 tree decl;
6641 /* Don't use anchors for mergeable sections. The linker might move
6642 the objects around. */
6643 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6644 if (sect->common.flags & SECTION_MERGE)
6645 return false;
6647 /* Don't use anchors for small data sections. The small data register
6648 acts as an anchor for such sections. */
6649 if (sect->common.flags & SECTION_SMALL)
6650 return false;
6652 decl = SYMBOL_REF_DECL (symbol);
6653 if (decl && DECL_P (decl))
6655 /* Don't use section anchors for decls that might be defined or
6656 usurped by other modules. */
6657 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6658 return false;
6660 /* Don't use section anchors for decls that will be placed in a
6661 small data section. */
6662 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6663 one above. The problem is that we only use SECTION_SMALL for
6664 sections that should be marked as small in the section directive. */
6665 if (targetm.in_small_data_p (decl))
6666 return false;
6668 return true;
6671 /* Return true when RESOLUTION indicate that symbol will be bound to the
6672 definition provided by current .o file. */
6674 static bool
6675 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
6677 return (resolution == LDPR_PREVAILING_DEF
6678 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6679 || resolution == LDPR_PREVAILING_DEF_IRONLY);
6682 /* Return true when RESOLUTION indicate that symbol will be bound locally
6683 within current executable or DSO. */
6685 static bool
6686 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
6688 return (resolution == LDPR_PREVAILING_DEF
6689 || resolution == LDPR_PREVAILING_DEF_IRONLY
6690 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6691 || resolution == LDPR_PREEMPTED_REG
6692 || resolution == LDPR_PREEMPTED_IR
6693 || resolution == LDPR_RESOLVED_IR
6694 || resolution == LDPR_RESOLVED_EXEC);
6697 /* Assume ELF-ish defaults, since that's pretty much the most liberal
6698 wrt cross-module name binding. */
6700 bool
6701 default_binds_local_p (const_tree exp)
6703 return default_binds_local_p_1 (exp, flag_shlib);
6706 bool
6707 default_binds_local_p_1 (const_tree exp, int shlib)
6709 bool local_p;
6710 bool resolved_locally = false;
6711 bool resolved_to_local_def = false;
6713 /* With resolution file in hands, take look into resolutions.
6714 We can't just return true for resolved_locally symbols,
6715 because dynamic linking might overwrite symbols
6716 in shared libraries. */
6717 if (TREE_CODE (exp) == VAR_DECL && TREE_PUBLIC (exp)
6718 && (TREE_STATIC (exp) || DECL_EXTERNAL (exp)))
6720 varpool_node *vnode = varpool_node::get (exp);
6721 if (vnode && (resolution_local_p (vnode->resolution) || vnode->in_other_partition))
6722 resolved_locally = true;
6723 if (vnode
6724 && resolution_to_local_definition_p (vnode->resolution))
6725 resolved_to_local_def = true;
6727 else if (TREE_CODE (exp) == FUNCTION_DECL && TREE_PUBLIC (exp))
6729 struct cgraph_node *node = cgraph_node::get (exp);
6730 if (node
6731 && (resolution_local_p (node->resolution) || node->in_other_partition))
6732 resolved_locally = true;
6733 if (node
6734 && resolution_to_local_definition_p (node->resolution))
6735 resolved_to_local_def = true;
6738 /* A non-decl is an entry in the constant pool. */
6739 if (!DECL_P (exp))
6740 local_p = true;
6741 /* Weakrefs may not bind locally, even though the weakref itself is always
6742 static and therefore local. Similarly, the resolver for ifunc functions
6743 might resolve to a non-local function.
6744 FIXME: We can resolve the weakref case more curefuly by looking at the
6745 weakref alias. */
6746 else if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
6747 || (TREE_CODE (exp) == FUNCTION_DECL
6748 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
6749 local_p = false;
6750 /* Static variables are always local. */
6751 else if (! TREE_PUBLIC (exp))
6752 local_p = true;
6753 /* A variable is local if the user has said explicitly that it will
6754 be. */
6755 else if ((DECL_VISIBILITY_SPECIFIED (exp)
6756 || resolved_to_local_def)
6757 && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6758 local_p = true;
6759 /* Variables defined outside this object might not be local. */
6760 else if (DECL_EXTERNAL (exp) && !resolved_locally)
6761 local_p = false;
6762 /* If defined in this object and visibility is not default, must be
6763 local. */
6764 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6765 local_p = true;
6766 /* Default visibility weak data can be overridden by a strong symbol
6767 in another module and so are not local. */
6768 else if (DECL_WEAK (exp)
6769 && !resolved_locally)
6770 local_p = false;
6771 /* If PIC, then assume that any global name can be overridden by
6772 symbols resolved from other modules. */
6773 else if (shlib)
6774 local_p = false;
6775 /* Uninitialized COMMON variable may be unified with symbols
6776 resolved from other modules. */
6777 else if (DECL_COMMON (exp)
6778 && !resolved_locally
6779 && (DECL_INITIAL (exp) == NULL
6780 || (!in_lto_p && DECL_INITIAL (exp) == error_mark_node)))
6781 local_p = false;
6782 /* Otherwise we're left with initialized (or non-common) global data
6783 which is of necessity defined locally. */
6784 else
6785 local_p = true;
6787 return local_p;
6790 /* Return true when references to DECL must bind to current definition in
6791 final executable.
6793 The condition is usually equivalent to whether the function binds to the
6794 current module (shared library or executable), that is to binds_local_p.
6795 We use this fact to avoid need for another target hook and implement
6796 the logic using binds_local_p and just special cases where
6797 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
6798 the weak definitions (that can be overwritten at linktime by other
6799 definition from different object file) and when resolution info is available
6800 we simply use the knowledge passed to us by linker plugin. */
6801 bool
6802 decl_binds_to_current_def_p (const_tree decl)
6804 gcc_assert (DECL_P (decl));
6805 if (!targetm.binds_local_p (decl))
6806 return false;
6807 if (!TREE_PUBLIC (decl))
6808 return true;
6809 /* When resolution is available, just use it. */
6810 if (TREE_CODE (decl) == VAR_DECL
6811 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl)))
6813 varpool_node *vnode = varpool_node::get (decl);
6814 if (vnode
6815 && vnode->resolution != LDPR_UNKNOWN)
6816 return resolution_to_local_definition_p (vnode->resolution);
6818 else if (TREE_CODE (decl) == FUNCTION_DECL)
6820 struct cgraph_node *node = cgraph_node::get (decl);
6821 if (node
6822 && node->resolution != LDPR_UNKNOWN)
6823 return resolution_to_local_definition_p (node->resolution);
6825 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
6826 binds locally but still can be overwritten), DECL_COMMON (can be merged
6827 with a non-common definition somewhere in the same module) or
6828 DECL_EXTERNAL.
6829 This rely on fact that binds_local_p behave as decl_replaceable_p
6830 for all other declaration types. */
6831 if (DECL_WEAK (decl))
6832 return false;
6833 if (DECL_COMMON (decl)
6834 && (DECL_INITIAL (decl) == NULL
6835 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
6836 return false;
6837 if (DECL_EXTERNAL (decl))
6838 return false;
6839 return true;
6842 /* A replaceable function or variable is one which may be replaced
6843 at link-time with an entirely different definition, provided that the
6844 replacement has the same type. For example, functions declared
6845 with __attribute__((weak)) on most systems are replaceable.
6847 COMDAT functions are not replaceable, since all definitions of the
6848 function must be equivalent. It is important that COMDAT functions
6849 not be treated as replaceable so that use of C++ template
6850 instantiations is not penalized. */
6852 bool
6853 decl_replaceable_p (tree decl)
6855 gcc_assert (DECL_P (decl));
6856 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
6857 return false;
6858 if (!flag_semantic_interposition
6859 && !DECL_WEAK (decl))
6860 return false;
6861 return !decl_binds_to_current_def_p (decl);
6864 /* Default function to output code that will globalize a label. A
6865 target must define GLOBAL_ASM_OP or provide its own function to
6866 globalize a label. */
6867 #ifdef GLOBAL_ASM_OP
6868 void
6869 default_globalize_label (FILE * stream, const char *name)
6871 fputs (GLOBAL_ASM_OP, stream);
6872 assemble_name (stream, name);
6873 putc ('\n', stream);
6875 #endif /* GLOBAL_ASM_OP */
6877 /* Default function to output code that will globalize a declaration. */
6878 void
6879 default_globalize_decl_name (FILE * stream, tree decl)
6881 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
6882 targetm.asm_out.globalize_label (stream, name);
6885 /* Default function to output a label for unwind information. The
6886 default is to do nothing. A target that needs nonlocal labels for
6887 unwind information must provide its own function to do this. */
6888 void
6889 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
6890 tree decl ATTRIBUTE_UNUSED,
6891 int for_eh ATTRIBUTE_UNUSED,
6892 int empty ATTRIBUTE_UNUSED)
6896 /* Default function to output a label to divide up the exception table.
6897 The default is to do nothing. A target that needs/wants to divide
6898 up the table must provide it's own function to do this. */
6899 void
6900 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
6904 /* This is how to output an internal numbered label where PREFIX is
6905 the class of label and LABELNO is the number within the class. */
6907 void
6908 default_generate_internal_label (char *buf, const char *prefix,
6909 unsigned long labelno)
6911 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6914 /* This is how to output an internal numbered label where PREFIX is
6915 the class of label and LABELNO is the number within the class. */
6917 void
6918 default_internal_label (FILE *stream, const char *prefix,
6919 unsigned long labelno)
6921 char *const buf = (char *) alloca (40 + strlen (prefix));
6922 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6923 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
6927 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
6929 void
6930 default_asm_declare_constant_name (FILE *file, const char *name,
6931 const_tree exp ATTRIBUTE_UNUSED,
6932 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
6934 assemble_label (file, name);
6937 /* This is the default behavior at the beginning of a file. It's
6938 controlled by two other target-hook toggles. */
6939 void
6940 default_file_start (void)
6942 if (targetm.asm_file_start_app_off
6943 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
6944 fputs (ASM_APP_OFF, asm_out_file);
6946 if (targetm.asm_file_start_file_directive)
6947 output_file_directive (asm_out_file, main_input_filename);
6950 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
6951 which emits a special section directive used to indicate whether or
6952 not this object file needs an executable stack. This is primarily
6953 a GNU extension to ELF but could be used on other targets. */
6955 int trampolines_created;
6957 void
6958 file_end_indicate_exec_stack (void)
6960 unsigned int flags = SECTION_DEBUG;
6961 if (trampolines_created)
6962 flags |= SECTION_CODE;
6964 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
6967 /* Emit a special section directive to indicate that this object file
6968 was compiled with -fsplit-stack. This is used to let the linker
6969 detect calls between split-stack code and non-split-stack code, so
6970 that it can modify the split-stack code to allocate a sufficiently
6971 large stack. We emit another special section if there are any
6972 functions in this file which have the no_split_stack attribute, to
6973 prevent the linker from warning about being unable to convert the
6974 functions if they call non-split-stack code. */
6976 void
6977 file_end_indicate_split_stack (void)
6979 if (flag_split_stack)
6981 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
6982 NULL));
6983 if (saw_no_split_stack)
6984 switch_to_section (get_section (".note.GNU-no-split-stack",
6985 SECTION_DEBUG, NULL));
6989 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
6990 a get_unnamed_section callback. */
6992 void
6993 output_section_asm_op (const void *directive)
6995 fprintf (asm_out_file, "%s\n", (const char *) directive);
6998 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
6999 the current section is NEW_SECTION. */
7001 void
7002 switch_to_section (section *new_section)
7004 if (in_section == new_section)
7005 return;
7007 if (new_section->common.flags & SECTION_FORGET)
7008 in_section = NULL;
7009 else
7010 in_section = new_section;
7012 switch (SECTION_STYLE (new_section))
7014 case SECTION_NAMED:
7015 targetm.asm_out.named_section (new_section->named.name,
7016 new_section->named.common.flags,
7017 new_section->named.decl);
7018 break;
7020 case SECTION_UNNAMED:
7021 new_section->unnamed.callback (new_section->unnamed.data);
7022 break;
7024 case SECTION_NOSWITCH:
7025 gcc_unreachable ();
7026 break;
7029 new_section->common.flags |= SECTION_DECLARED;
7032 /* If block symbol SYMBOL has not yet been assigned an offset, place
7033 it at the end of its block. */
7035 void
7036 place_block_symbol (rtx symbol)
7038 unsigned HOST_WIDE_INT size, mask, offset;
7039 struct constant_descriptor_rtx *desc;
7040 unsigned int alignment;
7041 struct object_block *block;
7042 tree decl;
7044 gcc_assert (SYMBOL_REF_BLOCK (symbol));
7045 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7046 return;
7048 /* Work out the symbol's size and alignment. */
7049 if (CONSTANT_POOL_ADDRESS_P (symbol))
7051 desc = SYMBOL_REF_CONSTANT (symbol);
7052 alignment = desc->align;
7053 size = GET_MODE_SIZE (desc->mode);
7055 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7057 decl = SYMBOL_REF_DECL (symbol);
7058 alignment = DECL_ALIGN (decl);
7059 size = get_constant_size (DECL_INITIAL (decl));
7060 if ((flag_sanitize & SANITIZE_ADDRESS)
7061 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7062 && asan_protect_global (DECL_INITIAL (decl)))
7063 size += asan_red_zone_size (size);
7065 else
7067 struct symtab_node *snode;
7068 decl = SYMBOL_REF_DECL (symbol);
7070 snode = symtab_node::get (decl);
7071 if (snode->alias)
7073 rtx target = DECL_RTL (snode->ultimate_alias_target ()->decl);
7075 place_block_symbol (target);
7076 SYMBOL_REF_BLOCK_OFFSET (symbol) = SYMBOL_REF_BLOCK_OFFSET (target);
7077 return;
7079 alignment = get_variable_align (decl);
7080 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7081 if ((flag_sanitize & SANITIZE_ADDRESS)
7082 && asan_protect_global (decl))
7084 size += asan_red_zone_size (size);
7085 alignment = MAX (alignment,
7086 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7090 /* Calculate the object's offset from the start of the block. */
7091 block = SYMBOL_REF_BLOCK (symbol);
7092 mask = alignment / BITS_PER_UNIT - 1;
7093 offset = (block->size + mask) & ~mask;
7094 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7096 /* Record the block's new alignment and size. */
7097 block->alignment = MAX (block->alignment, alignment);
7098 block->size = offset + size;
7100 vec_safe_push (block->objects, symbol);
7103 /* Return the anchor that should be used to address byte offset OFFSET
7104 from the first object in BLOCK. MODEL is the TLS model used
7105 to access it. */
7108 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7109 enum tls_model model)
7111 char label[100];
7112 unsigned int begin, middle, end;
7113 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7114 rtx anchor;
7116 /* Work out the anchor's offset. Use an offset of 0 for the first
7117 anchor so that we don't pessimize the case where we take the address
7118 of a variable at the beginning of the block. This is particularly
7119 useful when a block has only one variable assigned to it.
7121 We try to place anchors RANGE bytes apart, so there can then be
7122 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7123 a ptr_mode offset. With some target settings, the lowest such
7124 anchor might be out of range for the lowest ptr_mode offset;
7125 likewise the highest anchor for the highest offset. Use anchors
7126 at the extreme ends of the ptr_mode range in such cases.
7128 All arithmetic uses unsigned integers in order to avoid
7129 signed overflow. */
7130 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7131 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7132 range = max_offset - min_offset + 1;
7133 if (range == 0)
7134 offset = 0;
7135 else
7137 bias = 1 << (GET_MODE_BITSIZE (ptr_mode) - 1);
7138 if (offset < 0)
7140 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7141 delta -= delta % range;
7142 if (delta > bias)
7143 delta = bias;
7144 offset = (HOST_WIDE_INT) (-delta);
7146 else
7148 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7149 delta -= delta % range;
7150 if (delta > bias - 1)
7151 delta = bias - 1;
7152 offset = (HOST_WIDE_INT) delta;
7156 /* Do a binary search to see if there's already an anchor we can use.
7157 Set BEGIN to the new anchor's index if not. */
7158 begin = 0;
7159 end = vec_safe_length (block->anchors);
7160 while (begin != end)
7162 middle = (end + begin) / 2;
7163 anchor = (*block->anchors)[middle];
7164 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7165 end = middle;
7166 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7167 begin = middle + 1;
7168 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7169 end = middle;
7170 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7171 begin = middle + 1;
7172 else
7173 return anchor;
7176 /* Create a new anchor with a unique label. */
7177 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7178 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7179 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7180 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7182 /* Insert it at index BEGIN. */
7183 vec_safe_insert (block->anchors, begin, anchor);
7184 return anchor;
7187 /* Output the objects in BLOCK. */
7189 static void
7190 output_object_block (struct object_block *block)
7192 struct constant_descriptor_rtx *desc;
7193 unsigned int i;
7194 HOST_WIDE_INT offset;
7195 tree decl;
7196 rtx symbol;
7198 if (!block->objects)
7199 return;
7201 /* Switch to the section and make sure that the first byte is
7202 suitably aligned. */
7203 switch_to_section (block->sect);
7204 assemble_align (block->alignment);
7206 /* Define the values of all anchors relative to the current section
7207 position. */
7208 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7209 targetm.asm_out.output_anchor (symbol);
7211 /* Output the objects themselves. */
7212 offset = 0;
7213 FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7215 /* Move to the object's offset, padding with zeros if necessary. */
7216 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7217 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7218 if (CONSTANT_POOL_ADDRESS_P (symbol))
7220 desc = SYMBOL_REF_CONSTANT (symbol);
7221 output_constant_pool_1 (desc, 1);
7222 offset += GET_MODE_SIZE (desc->mode);
7224 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7226 HOST_WIDE_INT size;
7227 decl = SYMBOL_REF_DECL (symbol);
7228 assemble_constant_contents (DECL_INITIAL (decl), XSTR (symbol, 0),
7229 DECL_ALIGN (decl));
7230 size = get_constant_size (DECL_INITIAL (decl));
7231 offset += size;
7232 if ((flag_sanitize & SANITIZE_ADDRESS)
7233 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7234 && asan_protect_global (DECL_INITIAL (decl)))
7236 size = asan_red_zone_size (size);
7237 assemble_zeros (size);
7238 offset += size;
7241 else
7243 HOST_WIDE_INT size;
7244 decl = SYMBOL_REF_DECL (symbol);
7245 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7246 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7247 offset += size;
7248 if ((flag_sanitize & SANITIZE_ADDRESS)
7249 && asan_protect_global (decl))
7251 size = asan_red_zone_size (size);
7252 assemble_zeros (size);
7253 offset += size;
7259 /* A htab_traverse callback used to call output_object_block for
7260 each member of object_block_htab. */
7262 static int
7263 output_object_block_htab (void **slot, void *data ATTRIBUTE_UNUSED)
7265 output_object_block ((struct object_block *) (*slot));
7266 return 1;
7269 /* Output the definitions of all object_blocks. */
7271 void
7272 output_object_blocks (void)
7274 htab_traverse (object_block_htab, output_object_block_htab, NULL);
7277 /* This function provides a possible implementation of the
7278 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7279 by -frecord-gcc-switches it creates a new mergeable, string section in the
7280 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7281 contains the switches in ASCII format.
7283 FIXME: This code does not correctly handle double quote characters
7284 that appear inside strings, (it strips them rather than preserving them).
7285 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7286 characters - instead it treats them as sub-string separators. Since
7287 we want to emit NUL strings terminators into the object file we have to use
7288 ASM_OUTPUT_SKIP. */
7291 elf_record_gcc_switches (print_switch_type type, const char * name)
7293 switch (type)
7295 case SWITCH_TYPE_PASSED:
7296 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7297 ASM_OUTPUT_SKIP (asm_out_file, (unsigned HOST_WIDE_INT) 1);
7298 break;
7300 case SWITCH_TYPE_DESCRIPTIVE:
7301 if (name == NULL)
7303 /* Distinguish between invocations where name is NULL. */
7304 static bool started = false;
7306 if (!started)
7308 section * sec;
7310 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7311 SECTION_DEBUG
7312 | SECTION_MERGE
7313 | SECTION_STRINGS
7314 | (SECTION_ENTSIZE & 1),
7315 NULL);
7316 switch_to_section (sec);
7317 started = true;
7321 default:
7322 break;
7325 /* The return value is currently ignored by the caller, but must be 0.
7326 For -fverbose-asm the return value would be the number of characters
7327 emitted into the assembler file. */
7328 return 0;
7331 /* Emit text to declare externally defined symbols. It is needed to
7332 properly support non-default visibility. */
7333 void
7334 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7335 tree decl,
7336 const char *name ATTRIBUTE_UNUSED)
7338 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7339 set in order to avoid putting out names that are never really
7340 used. */
7341 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7342 && targetm.binds_local_p (decl))
7343 maybe_assemble_visibility (decl);
7346 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7348 void
7349 default_asm_output_source_filename (FILE *file, const char *name)
7351 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7352 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7353 #else
7354 fprintf (file, "\t.file\t");
7355 output_quoted_string (file, name);
7356 putc ('\n', file);
7357 #endif
7360 /* Output a file name in the form wanted by System V. */
7362 void
7363 output_file_directive (FILE *asm_file, const char *input_name)
7365 int len;
7366 const char *na;
7368 if (input_name == NULL)
7369 input_name = "<stdin>";
7370 else
7371 input_name = remap_debug_filename (input_name);
7373 len = strlen (input_name);
7374 na = input_name + len;
7376 /* NA gets INPUT_NAME sans directory names. */
7377 while (na > input_name)
7379 if (IS_DIR_SEPARATOR (na[-1]))
7380 break;
7381 na--;
7384 targetm.asm_out.output_source_filename (asm_file, na);
7387 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7388 EXP. */
7390 make_debug_expr_from_rtl (const_rtx exp)
7392 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7393 enum machine_mode mode = GET_MODE (exp);
7394 rtx dval;
7396 DECL_ARTIFICIAL (ddecl) = 1;
7397 if (REG_P (exp) && REG_EXPR (exp))
7398 type = TREE_TYPE (REG_EXPR (exp));
7399 else if (MEM_P (exp) && MEM_EXPR (exp))
7400 type = TREE_TYPE (MEM_EXPR (exp));
7401 else
7402 type = NULL_TREE;
7403 if (type && TYPE_MODE (type) == mode)
7404 TREE_TYPE (ddecl) = type;
7405 else
7406 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7407 DECL_MODE (ddecl) = mode;
7408 dval = gen_rtx_DEBUG_EXPR (mode);
7409 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7410 SET_DECL_RTL (ddecl, dval);
7411 return dval;
7414 #ifdef ELF_ASCII_ESCAPES
7415 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7417 void
7418 default_elf_asm_output_limited_string (FILE *f, const char *s)
7420 int escape;
7421 unsigned char c;
7423 fputs (STRING_ASM_OP, f);
7424 putc ('"', f);
7425 while (*s != '\0')
7427 c = *s;
7428 escape = ELF_ASCII_ESCAPES[c];
7429 switch (escape)
7431 case 0:
7432 putc (c, f);
7433 break;
7434 case 1:
7435 /* TODO: Print in hex with fast function, important for -flto. */
7436 fprintf (f, "\\%03o", c);
7437 break;
7438 default:
7439 putc ('\\', f);
7440 putc (escape, f);
7441 break;
7443 s++;
7445 putc ('\"', f);
7446 putc ('\n', f);
7449 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7451 void
7452 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7454 const char *limit = s + len;
7455 const char *last_null = NULL;
7456 unsigned bytes_in_chunk = 0;
7457 unsigned char c;
7458 int escape;
7460 for (; s < limit; s++)
7462 const char *p;
7464 if (bytes_in_chunk >= 60)
7466 putc ('\"', f);
7467 putc ('\n', f);
7468 bytes_in_chunk = 0;
7471 if (s > last_null)
7473 for (p = s; p < limit && *p != '\0'; p++)
7474 continue;
7475 last_null = p;
7477 else
7478 p = last_null;
7480 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7482 if (bytes_in_chunk > 0)
7484 putc ('\"', f);
7485 putc ('\n', f);
7486 bytes_in_chunk = 0;
7489 default_elf_asm_output_limited_string (f, s);
7490 s = p;
7492 else
7494 if (bytes_in_chunk == 0)
7495 fputs (ASCII_DATA_ASM_OP "\"", f);
7497 c = *s;
7498 escape = ELF_ASCII_ESCAPES[c];
7499 switch (escape)
7501 case 0:
7502 putc (c, f);
7503 bytes_in_chunk++;
7504 break;
7505 case 1:
7506 /* TODO: Print in hex with fast function, important for -flto. */
7507 fprintf (f, "\\%03o", c);
7508 bytes_in_chunk += 4;
7509 break;
7510 default:
7511 putc ('\\', f);
7512 putc (escape, f);
7513 bytes_in_chunk += 2;
7514 break;
7520 if (bytes_in_chunk > 0)
7522 putc ('\"', f);
7523 putc ('\n', f);
7526 #endif
7528 static GTY(()) section *elf_init_array_section;
7529 static GTY(()) section *elf_fini_array_section;
7531 static section *
7532 get_elf_initfini_array_priority_section (int priority,
7533 bool constructor_p)
7535 section *sec;
7536 if (priority != DEFAULT_INIT_PRIORITY)
7538 char buf[18];
7539 sprintf (buf, "%s.%.5u",
7540 constructor_p ? ".init_array" : ".fini_array",
7541 priority);
7542 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7544 else
7546 if (constructor_p)
7548 if (elf_init_array_section == NULL)
7549 elf_init_array_section
7550 = get_section (".init_array",
7551 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7552 sec = elf_init_array_section;
7554 else
7556 if (elf_fini_array_section == NULL)
7557 elf_fini_array_section
7558 = get_section (".fini_array",
7559 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7560 sec = elf_fini_array_section;
7563 return sec;
7566 /* Use .init_array section for constructors. */
7568 void
7569 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7571 section *sec = get_elf_initfini_array_priority_section (priority,
7572 true);
7573 assemble_addr_to_section (symbol, sec);
7576 /* Use .fini_array section for destructors. */
7578 void
7579 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7581 section *sec = get_elf_initfini_array_priority_section (priority,
7582 false);
7583 assemble_addr_to_section (symbol, sec);
7586 /* Default TARGET_ASM_OUTPUT_IDENT hook.
7588 This is a bit of a cheat. The real default is a no-op, but this
7589 hook is the default for all targets with a .ident directive. */
7591 void
7592 default_asm_output_ident_directive (const char *ident_str)
7594 const char *ident_asm_op = "\t.ident\t";
7596 /* If we are still in the front end, do not write out the string
7597 to asm_out_file. Instead, add a fake top-level asm statement.
7598 This allows the front ends to use this hook without actually
7599 writing to asm_out_file, to handle #ident or Pragma Ident. */
7600 if (symtab->state == PARSING)
7602 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
7603 symtab->finalize_toplevel_asm (build_string (strlen (buf), buf));
7605 else
7606 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
7609 #include "gt-varasm.h"