Merge from trunk @215656.
[official-gcc.git] / gcc / varasm.c
blob9017f14c0b20f04f59fe6081a3cb5412c7f502ca
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, bool);
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 false);
1997 else
1998 /* Leave space for it. */
1999 assemble_zeros (tree_to_uhwi (DECL_SIZE_UNIT (decl)));
2003 /* Assemble everything that is needed for a variable or function declaration.
2004 Not used for automatic variables, and not used for function definitions.
2005 Should not be called for variables of incomplete structure type.
2007 TOP_LEVEL is nonzero if this variable has file scope.
2008 AT_END is nonzero if this is the special handling, at end of compilation,
2009 to define things that have had only tentative definitions.
2010 DONT_OUTPUT_DATA if nonzero means don't actually output the
2011 initial value (that will be done by the caller). */
2013 void
2014 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
2015 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
2017 const char *name;
2018 rtx decl_rtl, symbol;
2019 section *sect;
2020 unsigned int align;
2021 bool asan_protected = false;
2023 /* This function is supposed to handle VARIABLES. Ensure we have one. */
2024 gcc_assert (TREE_CODE (decl) == VAR_DECL);
2026 /* Emulated TLS had better not get this far. */
2027 gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl));
2029 last_assemble_variable_decl = 0;
2031 /* Normally no need to say anything here for external references,
2032 since assemble_external is called by the language-specific code
2033 when a declaration is first seen. */
2035 if (DECL_EXTERNAL (decl))
2036 return;
2038 /* Do nothing for global register variables. */
2039 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
2041 TREE_ASM_WRITTEN (decl) = 1;
2042 return;
2045 /* If type was incomplete when the variable was declared,
2046 see if it is complete now. */
2048 if (DECL_SIZE (decl) == 0)
2049 layout_decl (decl, 0);
2051 /* Still incomplete => don't allocate it; treat the tentative defn
2052 (which is what it must have been) as an `extern' reference. */
2054 if (!dont_output_data && DECL_SIZE (decl) == 0)
2056 error ("storage size of %q+D isn%'t known", decl);
2057 TREE_ASM_WRITTEN (decl) = 1;
2058 return;
2061 /* The first declaration of a variable that comes through this function
2062 decides whether it is global (in C, has external linkage)
2063 or local (in C, has internal linkage). So do nothing more
2064 if this function has already run. */
2066 if (TREE_ASM_WRITTEN (decl))
2067 return;
2069 /* Make sure targetm.encode_section_info is invoked before we set
2070 ASM_WRITTEN. */
2071 decl_rtl = DECL_RTL (decl);
2073 TREE_ASM_WRITTEN (decl) = 1;
2075 /* Do no output if -fsyntax-only. */
2076 if (flag_syntax_only)
2077 return;
2079 if (! dont_output_data
2080 && ! valid_constant_size_p (DECL_SIZE_UNIT (decl)))
2082 error ("size of variable %q+D is too large", decl);
2083 return;
2086 gcc_assert (MEM_P (decl_rtl));
2087 gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF);
2088 symbol = XEXP (decl_rtl, 0);
2090 /* If this symbol belongs to the tree constant pool, output the constant
2091 if it hasn't already been written. */
2092 if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
2094 tree decl = SYMBOL_REF_DECL (symbol);
2095 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
2096 output_constant_def_contents (symbol);
2097 return;
2100 app_disable ();
2102 name = XSTR (symbol, 0);
2103 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
2104 notice_global_symbol (decl);
2106 /* Compute the alignment of this data. */
2108 align_variable (decl, dont_output_data);
2110 if ((flag_sanitize & SANITIZE_ADDRESS)
2111 && asan_protect_global (decl))
2113 asan_protected = true;
2114 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
2115 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
2118 set_mem_align (decl_rtl, DECL_ALIGN (decl));
2120 align = get_variable_align (decl);
2122 if (TREE_PUBLIC (decl))
2123 maybe_assemble_visibility (decl);
2125 if (DECL_PRESERVE_P (decl))
2126 targetm.asm_out.mark_decl_preserved (name);
2128 /* First make the assembler name(s) global if appropriate. */
2129 sect = get_variable_section (decl, false);
2130 if (TREE_PUBLIC (decl)
2131 && (sect->common.flags & SECTION_COMMON) == 0)
2132 globalize_decl (decl);
2134 /* Output any data that we will need to use the address of. */
2135 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
2136 output_addressed_constants (DECL_INITIAL (decl));
2138 /* dbxout.c needs to know this. */
2139 if (sect && (sect->common.flags & SECTION_CODE) != 0)
2140 DECL_IN_TEXT_SECTION (decl) = 1;
2142 /* If the decl is part of an object_block, make sure that the decl
2143 has been positioned within its block, but do not write out its
2144 definition yet. output_object_blocks will do that later. */
2145 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
2147 gcc_assert (!dont_output_data);
2148 place_block_symbol (symbol);
2150 else if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
2151 assemble_noswitch_variable (decl, name, sect, align);
2152 else
2154 /* The following bit of code ensures that vtable_map
2155 variables are not only in the comdat section, but that
2156 each variable has its own unique comdat name. If this
2157 code is removed, the variables end up in the same section
2158 with a single comdat name.
2160 FIXME: resolve_unique_section needs to deal better with
2161 decls with both DECL_SECTION_NAME and DECL_ONE_ONLY. Once
2162 that is fixed, this if-else statement can be replaced with
2163 a single call to "switch_to_section (sect)". */
2164 if (sect->named.name
2165 && (strcmp (sect->named.name, ".vtable_map_vars") == 0))
2167 #if defined (OBJECT_FORMAT_ELF)
2168 targetm.asm_out.named_section (sect->named.name,
2169 sect->named.common.flags
2170 | SECTION_LINKONCE,
2171 DECL_NAME (decl));
2172 in_section = sect;
2173 #else
2174 switch_to_section (sect);
2175 #endif
2177 else
2178 switch_to_section (sect);
2179 if (align > BITS_PER_UNIT)
2180 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2181 assemble_variable_contents (decl, name, dont_output_data);
2182 if (asan_protected)
2184 unsigned HOST_WIDE_INT int size
2185 = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2186 assemble_zeros (asan_red_zone_size (size));
2192 /* Given a function declaration (FN_DECL), this function assembles the
2193 function into the .preinit_array section. */
2195 void
2196 assemble_vtv_preinit_initializer (tree fn_decl)
2198 section *sect;
2199 unsigned flags = SECTION_WRITE;
2200 rtx symbol = XEXP (DECL_RTL (fn_decl), 0);
2202 flags |= SECTION_NOTYPE;
2203 sect = get_section (".preinit_array", flags, fn_decl);
2204 switch_to_section (sect);
2205 assemble_addr_to_section (symbol, sect);
2208 /* Return 1 if type TYPE contains any pointers. */
2210 static int
2211 contains_pointers_p (tree type)
2213 switch (TREE_CODE (type))
2215 case POINTER_TYPE:
2216 case REFERENCE_TYPE:
2217 /* I'm not sure whether OFFSET_TYPE needs this treatment,
2218 so I'll play safe and return 1. */
2219 case OFFSET_TYPE:
2220 return 1;
2222 case RECORD_TYPE:
2223 case UNION_TYPE:
2224 case QUAL_UNION_TYPE:
2226 tree fields;
2227 /* For a type that has fields, see if the fields have pointers. */
2228 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2229 if (TREE_CODE (fields) == FIELD_DECL
2230 && contains_pointers_p (TREE_TYPE (fields)))
2231 return 1;
2232 return 0;
2235 case ARRAY_TYPE:
2236 /* An array type contains pointers if its element type does. */
2237 return contains_pointers_p (TREE_TYPE (type));
2239 default:
2240 return 0;
2244 /* We delay assemble_external processing until
2245 the compilation unit is finalized. This is the best we can do for
2246 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2247 it all the way to final. See PR 17982 for further discussion. */
2248 static GTY(()) tree pending_assemble_externals;
2250 #ifdef ASM_OUTPUT_EXTERNAL
2251 /* Some targets delay some output to final using TARGET_ASM_FILE_END.
2252 As a result, assemble_external can be called after the list of externals
2253 is processed and the pointer set destroyed. */
2254 static bool pending_assemble_externals_processed;
2256 /* Avoid O(external_decls**2) lookups in the pending_assemble_externals
2257 TREE_LIST in assemble_external. */
2258 static hash_set<tree> *pending_assemble_externals_set;
2260 /* True if DECL is a function decl for which no out-of-line copy exists.
2261 It is assumed that DECL's assembler name has been set. */
2263 static bool
2264 incorporeal_function_p (tree decl)
2266 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
2268 const char *name;
2270 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2271 && (DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA
2272 || DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA_WITH_ALIGN))
2273 return true;
2275 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2276 /* Atomic or sync builtins which have survived this far will be
2277 resolved externally and therefore are not incorporeal. */
2278 if (strncmp (name, "__builtin_", 10) == 0)
2279 return true;
2281 return false;
2284 /* Actually do the tests to determine if this is necessary, and invoke
2285 ASM_OUTPUT_EXTERNAL. */
2286 static void
2287 assemble_external_real (tree decl)
2289 rtx rtl = DECL_RTL (decl);
2291 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2292 && !SYMBOL_REF_USED (XEXP (rtl, 0))
2293 && !incorporeal_function_p (decl))
2295 /* Some systems do require some output. */
2296 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2297 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2300 #endif
2302 void
2303 process_pending_assemble_externals (void)
2305 #ifdef ASM_OUTPUT_EXTERNAL
2306 tree list;
2307 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2308 assemble_external_real (TREE_VALUE (list));
2310 pending_assemble_externals = 0;
2311 pending_assemble_externals_processed = true;
2312 delete pending_assemble_externals_set;
2313 #endif
2316 /* This TREE_LIST contains any weak symbol declarations waiting
2317 to be emitted. */
2318 static GTY(()) tree weak_decls;
2320 /* Output something to declare an external symbol to the assembler,
2321 and qualifiers such as weakness. (Most assemblers don't need
2322 extern declaration, so we normally output nothing.) Do nothing if
2323 DECL is not external. */
2325 void
2326 assemble_external (tree decl ATTRIBUTE_UNUSED)
2328 /* Make sure that the ASM_OUT_FILE is open.
2329 If it's not, we should not be calling this function. */
2330 gcc_assert (asm_out_file);
2332 /* In a perfect world, the following condition would be true.
2333 Sadly, the Java and Go front ends emit assembly *from the front end*,
2334 bypassing the call graph. See PR52739. Fix before GCC 4.8. */
2335 #if 0
2336 /* This function should only be called if we are expanding, or have
2337 expanded, to RTL.
2338 Ideally, only final.c would be calling this function, but it is
2339 not clear whether that would break things somehow. See PR 17982
2340 for further discussion. */
2341 gcc_assert (state == EXPANSION
2342 || state == FINISHED);
2343 #endif
2345 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2346 return;
2348 /* We want to output annotation for weak and external symbols at
2349 very last to check if they are references or not. */
2351 if (TARGET_SUPPORTS_WEAK
2352 && DECL_WEAK (decl)
2353 /* TREE_STATIC is a weird and abused creature which is not
2354 generally the right test for whether an entity has been
2355 locally emitted, inlined or otherwise not-really-extern, but
2356 for declarations that can be weak, it happens to be
2357 match. */
2358 && !TREE_STATIC (decl)
2359 && lookup_attribute ("weak", DECL_ATTRIBUTES (decl))
2360 && value_member (decl, weak_decls) == NULL_TREE)
2361 weak_decls = tree_cons (NULL, decl, weak_decls);
2363 #ifdef ASM_OUTPUT_EXTERNAL
2364 if (pending_assemble_externals_processed)
2366 assemble_external_real (decl);
2367 return;
2370 if (! pending_assemble_externals_set->add (decl))
2371 pending_assemble_externals = tree_cons (NULL, decl,
2372 pending_assemble_externals);
2373 #endif
2376 /* Similar, for calling a library function FUN. */
2378 void
2379 assemble_external_libcall (rtx fun)
2381 /* Declare library function name external when first used, if nec. */
2382 if (! SYMBOL_REF_USED (fun))
2384 SYMBOL_REF_USED (fun) = 1;
2385 targetm.asm_out.external_libcall (fun);
2389 /* Assemble a label named NAME. */
2391 void
2392 assemble_label (FILE *file, const char *name)
2394 ASM_OUTPUT_LABEL (file, name);
2397 /* Set the symbol_referenced flag for ID. */
2398 void
2399 mark_referenced (tree id)
2401 TREE_SYMBOL_REFERENCED (id) = 1;
2404 /* Set the symbol_referenced flag for DECL and notify callgraph. */
2405 void
2406 mark_decl_referenced (tree decl)
2408 if (TREE_CODE (decl) == FUNCTION_DECL)
2410 /* Extern inline functions don't become needed when referenced.
2411 If we know a method will be emitted in other TU and no new
2412 functions can be marked reachable, just use the external
2413 definition. */
2414 struct cgraph_node *node = cgraph_node::get_create (decl);
2415 if (!DECL_EXTERNAL (decl)
2416 && !node->definition)
2417 node->mark_force_output ();
2419 else if (TREE_CODE (decl) == VAR_DECL)
2421 varpool_node *node = varpool_node::get_create (decl);
2422 /* C++ frontend use mark_decl_references to force COMDAT variables
2423 to be output that might appear dead otherwise. */
2424 node->force_output = true;
2426 /* else do nothing - we can get various sorts of CST nodes here,
2427 which do not need to be marked. */
2431 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS
2432 until we find an identifier that is not itself a transparent alias.
2433 Modify the alias passed to it by reference (and all aliases on the
2434 way to the ultimate target), such that they do not have to be
2435 followed again, and return the ultimate target of the alias
2436 chain. */
2438 static inline tree
2439 ultimate_transparent_alias_target (tree *alias)
2441 tree target = *alias;
2443 if (IDENTIFIER_TRANSPARENT_ALIAS (target))
2445 gcc_assert (TREE_CHAIN (target));
2446 target = ultimate_transparent_alias_target (&TREE_CHAIN (target));
2447 gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target)
2448 && ! TREE_CHAIN (target));
2449 *alias = target;
2452 return target;
2455 /* Output to FILE (an assembly file) a reference to NAME. If NAME
2456 starts with a *, the rest of NAME is output verbatim. Otherwise
2457 NAME is transformed in a target-specific way (usually by the
2458 addition of an underscore). */
2460 void
2461 assemble_name_raw (FILE *file, const char *name)
2463 if (name[0] == '*')
2464 fputs (&name[1], file);
2465 else
2466 ASM_OUTPUT_LABELREF (file, name);
2469 /* Like assemble_name_raw, but should be used when NAME might refer to
2470 an entity that is also represented as a tree (like a function or
2471 variable). If NAME does refer to such an entity, that entity will
2472 be marked as referenced. */
2474 void
2475 assemble_name (FILE *file, const char *name)
2477 const char *real_name;
2478 tree id;
2480 real_name = targetm.strip_name_encoding (name);
2482 id = maybe_get_identifier (real_name);
2483 if (id)
2485 tree id_orig = id;
2487 mark_referenced (id);
2488 ultimate_transparent_alias_target (&id);
2489 if (id != id_orig)
2490 name = IDENTIFIER_POINTER (id);
2491 gcc_assert (! TREE_CHAIN (id));
2494 assemble_name_raw (file, name);
2497 /* Allocate SIZE bytes writable static space with a gensym name
2498 and return an RTX to refer to its address. */
2501 assemble_static_space (unsigned HOST_WIDE_INT size)
2503 char name[12];
2504 const char *namestring;
2505 rtx x;
2507 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2508 ++const_labelno;
2509 namestring = ggc_strdup (name);
2511 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2512 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2514 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2515 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2516 BIGGEST_ALIGNMENT);
2517 #else
2518 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2519 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2520 #else
2522 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2523 so that each uninitialized object starts on such a boundary. */
2524 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2525 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2526 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2527 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2528 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2529 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2531 #endif
2532 #endif
2533 return x;
2536 /* Assemble the static constant template for function entry trampolines.
2537 This is done at most once per compilation.
2538 Returns an RTX for the address of the template. */
2540 static GTY(()) rtx initial_trampoline;
2543 assemble_trampoline_template (void)
2545 char label[256];
2546 const char *name;
2547 int align;
2548 rtx symbol;
2550 gcc_assert (targetm.asm_out.trampoline_template != NULL);
2552 if (initial_trampoline)
2553 return initial_trampoline;
2555 /* By default, put trampoline templates in read-only data section. */
2557 #ifdef TRAMPOLINE_SECTION
2558 switch_to_section (TRAMPOLINE_SECTION);
2559 #else
2560 switch_to_section (readonly_data_section);
2561 #endif
2563 /* Write the assembler code to define one. */
2564 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2565 if (align > 0)
2566 ASM_OUTPUT_ALIGN (asm_out_file, align);
2568 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2569 targetm.asm_out.trampoline_template (asm_out_file);
2571 /* Record the rtl to refer to it. */
2572 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2573 name = ggc_strdup (label);
2574 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2575 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2577 initial_trampoline = gen_const_mem (BLKmode, symbol);
2578 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2579 set_mem_size (initial_trampoline, TRAMPOLINE_SIZE);
2581 return initial_trampoline;
2584 /* A and B are either alignments or offsets. Return the minimum alignment
2585 that may be assumed after adding the two together. */
2587 static inline unsigned
2588 min_align (unsigned int a, unsigned int b)
2590 return (a | b) & -(a | b);
2593 /* Return the assembler directive for creating a given kind of integer
2594 object. SIZE is the number of bytes in the object and ALIGNED_P
2595 indicates whether it is known to be aligned. Return NULL if the
2596 assembly dialect has no such directive.
2598 The returned string should be printed at the start of a new line and
2599 be followed immediately by the object's initial value. */
2601 const char *
2602 integer_asm_op (int size, int aligned_p)
2604 struct asm_int_op *ops;
2606 if (aligned_p)
2607 ops = &targetm.asm_out.aligned_op;
2608 else
2609 ops = &targetm.asm_out.unaligned_op;
2611 switch (size)
2613 case 1:
2614 return targetm.asm_out.byte_op;
2615 case 2:
2616 return ops->hi;
2617 case 4:
2618 return ops->si;
2619 case 8:
2620 return ops->di;
2621 case 16:
2622 return ops->ti;
2623 default:
2624 return NULL;
2628 /* Use directive OP to assemble an integer object X. Print OP at the
2629 start of the line, followed immediately by the value of X. */
2631 void
2632 assemble_integer_with_op (const char *op, rtx x)
2634 fputs (op, asm_out_file);
2635 output_addr_const (asm_out_file, x);
2636 fputc ('\n', asm_out_file);
2639 /* The default implementation of the asm_out.integer target hook. */
2641 bool
2642 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2643 unsigned int size ATTRIBUTE_UNUSED,
2644 int aligned_p ATTRIBUTE_UNUSED)
2646 const char *op = integer_asm_op (size, aligned_p);
2647 /* Avoid GAS bugs for large values. Specifically negative values whose
2648 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2649 if (size > UNITS_PER_WORD && size > POINTER_SIZE_UNITS)
2650 return false;
2651 return op && (assemble_integer_with_op (op, x), true);
2654 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2655 the alignment of the integer in bits. Return 1 if we were able to output
2656 the constant, otherwise 0. We must be able to output the constant,
2657 if FORCE is nonzero. */
2659 bool
2660 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2662 int aligned_p;
2664 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2666 /* See if the target hook can handle this kind of object. */
2667 if (targetm.asm_out.integer (x, size, aligned_p))
2668 return true;
2670 /* If the object is a multi-byte one, try splitting it up. Split
2671 it into words it if is multi-word, otherwise split it into bytes. */
2672 if (size > 1)
2674 enum machine_mode omode, imode;
2675 unsigned int subalign;
2676 unsigned int subsize, i;
2677 enum mode_class mclass;
2679 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2680 subalign = MIN (align, subsize * BITS_PER_UNIT);
2681 if (GET_CODE (x) == CONST_FIXED)
2682 mclass = GET_MODE_CLASS (GET_MODE (x));
2683 else
2684 mclass = MODE_INT;
2686 omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0);
2687 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0);
2689 for (i = 0; i < size; i += subsize)
2691 rtx partial = simplify_subreg (omode, x, imode, i);
2692 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2693 break;
2695 if (i == size)
2696 return true;
2698 /* If we've printed some of it, but not all of it, there's no going
2699 back now. */
2700 gcc_assert (!i);
2703 gcc_assert (!force);
2705 return false;
2708 void
2709 assemble_real (REAL_VALUE_TYPE d, enum machine_mode mode, unsigned int align)
2711 long data[4] = {0, 0, 0, 0};
2712 int i;
2713 int bitsize, nelts, nunits, units_per;
2715 /* This is hairy. We have a quantity of known size. real_to_target
2716 will put it into an array of *host* longs, 32 bits per element
2717 (even if long is more than 32 bits). We need to determine the
2718 number of array elements that are occupied (nelts) and the number
2719 of *target* min-addressable units that will be occupied in the
2720 object file (nunits). We cannot assume that 32 divides the
2721 mode's bitsize (size * BITS_PER_UNIT) evenly.
2723 size * BITS_PER_UNIT is used here to make sure that padding bits
2724 (which might appear at either end of the value; real_to_target
2725 will include the padding bits in its output array) are included. */
2727 nunits = GET_MODE_SIZE (mode);
2728 bitsize = nunits * BITS_PER_UNIT;
2729 nelts = CEIL (bitsize, 32);
2730 units_per = 32 / BITS_PER_UNIT;
2732 real_to_target (data, &d, mode);
2734 /* Put out the first word with the specified alignment. */
2735 assemble_integer (GEN_INT (data[0]), MIN (nunits, units_per), align, 1);
2736 nunits -= units_per;
2738 /* Subsequent words need only 32-bit alignment. */
2739 align = min_align (align, 32);
2741 for (i = 1; i < nelts; i++)
2743 assemble_integer (GEN_INT (data[i]), MIN (nunits, units_per), align, 1);
2744 nunits -= units_per;
2748 /* Given an expression EXP with a constant value,
2749 reduce it to the sum of an assembler symbol and an integer.
2750 Store them both in the structure *VALUE.
2751 EXP must be reducible. */
2753 struct addr_const {
2754 rtx base;
2755 HOST_WIDE_INT offset;
2758 static void
2759 decode_addr_const (tree exp, struct addr_const *value)
2761 tree target = TREE_OPERAND (exp, 0);
2762 int offset = 0;
2763 rtx x;
2765 while (1)
2767 if (TREE_CODE (target) == COMPONENT_REF
2768 && tree_fits_shwi_p (byte_position (TREE_OPERAND (target, 1))))
2770 offset += int_byte_position (TREE_OPERAND (target, 1));
2771 target = TREE_OPERAND (target, 0);
2773 else if (TREE_CODE (target) == ARRAY_REF
2774 || TREE_CODE (target) == ARRAY_RANGE_REF)
2776 offset += (tree_to_uhwi (TYPE_SIZE_UNIT (TREE_TYPE (target)))
2777 * tree_to_shwi (TREE_OPERAND (target, 1)));
2778 target = TREE_OPERAND (target, 0);
2780 else if (TREE_CODE (target) == MEM_REF
2781 && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR)
2783 offset += mem_ref_offset (target).to_short_addr ();
2784 target = TREE_OPERAND (TREE_OPERAND (target, 0), 0);
2786 else if (TREE_CODE (target) == INDIRECT_REF
2787 && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR
2788 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0))
2789 == ADDR_EXPR)
2790 target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0);
2791 else
2792 break;
2795 switch (TREE_CODE (target))
2797 case VAR_DECL:
2798 case FUNCTION_DECL:
2799 x = DECL_RTL (target);
2800 break;
2802 case LABEL_DECL:
2803 x = gen_rtx_MEM (FUNCTION_MODE,
2804 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2805 break;
2807 case REAL_CST:
2808 case FIXED_CST:
2809 case STRING_CST:
2810 case COMPLEX_CST:
2811 case CONSTRUCTOR:
2812 case INTEGER_CST:
2813 x = output_constant_def (target, 1);
2814 break;
2816 default:
2817 gcc_unreachable ();
2820 gcc_assert (MEM_P (x));
2821 x = XEXP (x, 0);
2823 value->base = x;
2824 value->offset = offset;
2828 static GTY((param_is (struct constant_descriptor_tree)))
2829 htab_t const_desc_htab;
2831 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2833 /* Constant pool accessor function. */
2835 htab_t
2836 constant_pool_htab (void)
2838 return const_desc_htab;
2841 /* Compute a hash code for a constant expression. */
2843 static hashval_t
2844 const_desc_hash (const void *ptr)
2846 return ((const struct constant_descriptor_tree *)ptr)->hash;
2849 static hashval_t
2850 const_hash_1 (const tree exp)
2852 const char *p;
2853 hashval_t hi;
2854 int len, i;
2855 enum tree_code code = TREE_CODE (exp);
2857 /* Either set P and LEN to the address and len of something to hash and
2858 exit the switch or return a value. */
2860 switch (code)
2862 case INTEGER_CST:
2863 p = (char *) &TREE_INT_CST_ELT (exp, 0);
2864 len = TREE_INT_CST_NUNITS (exp) * sizeof (HOST_WIDE_INT);
2865 break;
2867 case REAL_CST:
2868 return real_hash (TREE_REAL_CST_PTR (exp));
2870 case FIXED_CST:
2871 return fixed_hash (TREE_FIXED_CST_PTR (exp));
2873 case STRING_CST:
2874 p = TREE_STRING_POINTER (exp);
2875 len = TREE_STRING_LENGTH (exp);
2876 break;
2878 case COMPLEX_CST:
2879 return (const_hash_1 (TREE_REALPART (exp)) * 5
2880 + const_hash_1 (TREE_IMAGPART (exp)));
2882 case VECTOR_CST:
2884 unsigned i;
2886 hi = 7 + VECTOR_CST_NELTS (exp);
2888 for (i = 0; i < VECTOR_CST_NELTS (exp); ++i)
2889 hi = hi * 563 + const_hash_1 (VECTOR_CST_ELT (exp, i));
2891 return hi;
2894 case CONSTRUCTOR:
2896 unsigned HOST_WIDE_INT idx;
2897 tree value;
2899 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2901 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
2902 if (value)
2903 hi = hi * 603 + const_hash_1 (value);
2905 return hi;
2908 case ADDR_EXPR:
2909 case FDESC_EXPR:
2911 struct addr_const value;
2913 decode_addr_const (exp, &value);
2914 switch (GET_CODE (value.base))
2916 case SYMBOL_REF:
2917 /* Don't hash the address of the SYMBOL_REF;
2918 only use the offset and the symbol name. */
2919 hi = value.offset;
2920 p = XSTR (value.base, 0);
2921 for (i = 0; p[i] != 0; i++)
2922 hi = ((hi * 613) + (unsigned) (p[i]));
2923 break;
2925 case LABEL_REF:
2926 hi = (value.offset
2927 + CODE_LABEL_NUMBER (LABEL_REF_LABEL (value.base)) * 13);
2928 break;
2930 default:
2931 gcc_unreachable ();
2934 return hi;
2936 case PLUS_EXPR:
2937 case POINTER_PLUS_EXPR:
2938 case MINUS_EXPR:
2939 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2940 + const_hash_1 (TREE_OPERAND (exp, 1)));
2942 CASE_CONVERT:
2943 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
2945 default:
2946 /* A language specific constant. Just hash the code. */
2947 return code;
2950 /* Compute hashing function. */
2951 hi = len;
2952 for (i = 0; i < len; i++)
2953 hi = ((hi * 613) + (unsigned) (p[i]));
2955 return hi;
2958 /* Wrapper of compare_constant, for the htab interface. */
2959 static int
2960 const_desc_eq (const void *p1, const void *p2)
2962 const struct constant_descriptor_tree *const c1
2963 = (const struct constant_descriptor_tree *) p1;
2964 const struct constant_descriptor_tree *const c2
2965 = (const struct constant_descriptor_tree *) p2;
2966 if (c1->hash != c2->hash)
2967 return 0;
2968 return compare_constant (c1->value, c2->value);
2971 /* Compare t1 and t2, and return 1 only if they are known to result in
2972 the same bit pattern on output. */
2974 static int
2975 compare_constant (const tree t1, const tree t2)
2977 enum tree_code typecode;
2979 if (t1 == NULL_TREE)
2980 return t2 == NULL_TREE;
2981 if (t2 == NULL_TREE)
2982 return 0;
2984 if (TREE_CODE (t1) != TREE_CODE (t2))
2985 return 0;
2987 switch (TREE_CODE (t1))
2989 case INTEGER_CST:
2990 /* Integer constants are the same only if the same width of type. */
2991 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2992 return 0;
2993 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2994 return 0;
2995 return tree_int_cst_equal (t1, t2);
2997 case REAL_CST:
2998 /* Real constants are the same only if the same width of type. */
2999 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3000 return 0;
3002 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
3004 case FIXED_CST:
3005 /* Fixed constants are the same only if the same width of type. */
3006 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3007 return 0;
3009 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
3011 case STRING_CST:
3012 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3013 return 0;
3015 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
3016 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
3017 TREE_STRING_LENGTH (t1)));
3019 case COMPLEX_CST:
3020 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
3021 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
3023 case VECTOR_CST:
3025 unsigned i;
3027 if (VECTOR_CST_NELTS (t1) != VECTOR_CST_NELTS (t2))
3028 return 0;
3030 for (i = 0; i < VECTOR_CST_NELTS (t1); ++i)
3031 if (!compare_constant (VECTOR_CST_ELT (t1, i),
3032 VECTOR_CST_ELT (t2, i)))
3033 return 0;
3035 return 1;
3038 case CONSTRUCTOR:
3040 vec<constructor_elt, va_gc> *v1, *v2;
3041 unsigned HOST_WIDE_INT idx;
3043 typecode = TREE_CODE (TREE_TYPE (t1));
3044 if (typecode != TREE_CODE (TREE_TYPE (t2)))
3045 return 0;
3047 if (typecode == ARRAY_TYPE)
3049 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
3050 /* For arrays, check that the sizes all match. */
3051 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
3052 || size_1 == -1
3053 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
3054 return 0;
3056 else
3058 /* For record and union constructors, require exact type
3059 equality. */
3060 if (TREE_TYPE (t1) != TREE_TYPE (t2))
3061 return 0;
3064 v1 = CONSTRUCTOR_ELTS (t1);
3065 v2 = CONSTRUCTOR_ELTS (t2);
3066 if (vec_safe_length (v1) != vec_safe_length (v2))
3067 return 0;
3069 for (idx = 0; idx < vec_safe_length (v1); ++idx)
3071 constructor_elt *c1 = &(*v1)[idx];
3072 constructor_elt *c2 = &(*v2)[idx];
3074 /* Check that each value is the same... */
3075 if (!compare_constant (c1->value, c2->value))
3076 return 0;
3077 /* ... and that they apply to the same fields! */
3078 if (typecode == ARRAY_TYPE)
3080 if (!compare_constant (c1->index, c2->index))
3081 return 0;
3083 else
3085 if (c1->index != c2->index)
3086 return 0;
3090 return 1;
3093 case ADDR_EXPR:
3094 case FDESC_EXPR:
3096 struct addr_const value1, value2;
3097 enum rtx_code code;
3098 int ret;
3100 decode_addr_const (t1, &value1);
3101 decode_addr_const (t2, &value2);
3103 if (value1.offset != value2.offset)
3104 return 0;
3106 code = GET_CODE (value1.base);
3107 if (code != GET_CODE (value2.base))
3108 return 0;
3110 switch (code)
3112 case SYMBOL_REF:
3113 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3114 break;
3116 case LABEL_REF:
3117 ret = (CODE_LABEL_NUMBER (LABEL_REF_LABEL (value1.base))
3118 == CODE_LABEL_NUMBER (LABEL_REF_LABEL (value2.base)));
3119 break;
3121 default:
3122 gcc_unreachable ();
3124 return ret;
3127 case PLUS_EXPR:
3128 case POINTER_PLUS_EXPR:
3129 case MINUS_EXPR:
3130 case RANGE_EXPR:
3131 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3132 && compare_constant (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3134 CASE_CONVERT:
3135 case VIEW_CONVERT_EXPR:
3136 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3138 default:
3139 return 0;
3142 gcc_unreachable ();
3145 /* Return the section into which constant EXP should be placed. */
3147 static section *
3148 get_constant_section (tree exp, unsigned int align)
3150 return targetm.asm_out.select_section (exp,
3151 compute_reloc_for_constant (exp),
3152 align);
3155 /* Return the size of constant EXP in bytes. */
3157 static HOST_WIDE_INT
3158 get_constant_size (tree exp)
3160 HOST_WIDE_INT size;
3162 size = int_size_in_bytes (TREE_TYPE (exp));
3163 if (TREE_CODE (exp) == STRING_CST)
3164 size = MAX (TREE_STRING_LENGTH (exp), size);
3165 return size;
3168 /* Subroutine of output_constant_def:
3169 No constant equal to EXP is known to have been output.
3170 Make a constant descriptor to enter EXP in the hash table.
3171 Assign the label number and construct RTL to refer to the
3172 constant's location in memory.
3173 Caller is responsible for updating the hash table. */
3175 static struct constant_descriptor_tree *
3176 build_constant_desc (tree exp)
3178 struct constant_descriptor_tree *desc;
3179 rtx symbol, rtl;
3180 char label[256];
3181 int labelno;
3182 tree decl;
3184 desc = ggc_alloc<constant_descriptor_tree> ();
3185 desc->value = exp;
3187 /* Create a string containing the label name, in LABEL. */
3188 labelno = const_labelno++;
3189 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3191 /* Construct the VAR_DECL associated with the constant. */
3192 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3193 TREE_TYPE (exp));
3194 DECL_ARTIFICIAL (decl) = 1;
3195 DECL_IGNORED_P (decl) = 1;
3196 TREE_READONLY (decl) = 1;
3197 TREE_STATIC (decl) = 1;
3198 TREE_ADDRESSABLE (decl) = 1;
3199 /* We don't set the RTL yet as this would cause varpool to assume that the
3200 variable is referenced. Moreover, it would just be dropped in LTO mode.
3201 Instead we set the flag that will be recognized in make_decl_rtl. */
3202 DECL_IN_CONSTANT_POOL (decl) = 1;
3203 DECL_INITIAL (decl) = desc->value;
3204 /* ??? CONSTANT_ALIGNMENT hasn't been updated for vector types on most
3205 architectures so use DATA_ALIGNMENT as well, except for strings. */
3206 if (TREE_CODE (exp) == STRING_CST)
3208 #ifdef CONSTANT_ALIGNMENT
3209 DECL_ALIGN (decl) = CONSTANT_ALIGNMENT (exp, DECL_ALIGN (decl));
3210 #endif
3212 else
3213 align_variable (decl, 0);
3215 /* Now construct the SYMBOL_REF and the MEM. */
3216 if (use_object_blocks_p ())
3218 section *sect = get_constant_section (exp, DECL_ALIGN (decl));
3219 symbol = create_block_symbol (ggc_strdup (label),
3220 get_block_for_section (sect), -1);
3222 else
3223 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3224 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3225 SET_SYMBOL_REF_DECL (symbol, decl);
3226 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3228 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3229 set_mem_attributes (rtl, exp, 1);
3230 set_mem_alias_set (rtl, 0);
3231 set_mem_alias_set (rtl, const_alias_set);
3233 /* We cannot share RTX'es in pool entries.
3234 Mark this piece of RTL as required for unsharing. */
3235 RTX_FLAG (rtl, used) = 1;
3237 /* Set flags or add text to the name to record information, such as
3238 that it is a local symbol. If the name is changed, the macro
3239 ASM_OUTPUT_LABELREF will have to know how to strip this
3240 information. This call might invalidate our local variable
3241 SYMBOL; we can't use it afterward. */
3242 targetm.encode_section_info (exp, rtl, true);
3244 desc->rtl = rtl;
3246 return desc;
3249 /* Return an rtx representing a reference to constant data in memory
3250 for the constant expression EXP.
3252 If assembler code for such a constant has already been output,
3253 return an rtx to refer to it.
3254 Otherwise, output such a constant in memory
3255 and generate an rtx for it.
3257 If DEFER is nonzero, this constant can be deferred and output only
3258 if referenced in the function after all optimizations.
3260 `const_desc_table' records which constants already have label strings. */
3263 output_constant_def (tree exp, int defer)
3265 struct constant_descriptor_tree *desc;
3266 struct constant_descriptor_tree key;
3267 void **loc;
3269 /* Look up EXP in the table of constant descriptors. If we didn't find
3270 it, create a new one. */
3271 key.value = exp;
3272 key.hash = const_hash_1 (exp);
3273 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3275 desc = (struct constant_descriptor_tree *) *loc;
3276 if (desc == 0)
3278 desc = build_constant_desc (exp);
3279 desc->hash = key.hash;
3280 *loc = desc;
3283 maybe_output_constant_def_contents (desc, defer);
3284 return desc->rtl;
3287 /* Subroutine of output_constant_def: Decide whether or not we need to
3288 output the constant DESC now, and if so, do it. */
3289 static void
3290 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3291 int defer)
3293 rtx symbol = XEXP (desc->rtl, 0);
3294 tree exp = desc->value;
3296 if (flag_syntax_only)
3297 return;
3299 if (TREE_ASM_WRITTEN (exp))
3300 /* Already output; don't do it again. */
3301 return;
3303 /* We can always defer constants as long as the context allows
3304 doing so. */
3305 if (defer)
3307 /* Increment n_deferred_constants if it exists. It needs to be at
3308 least as large as the number of constants actually referred to
3309 by the function. If it's too small we'll stop looking too early
3310 and fail to emit constants; if it's too large we'll only look
3311 through the entire function when we could have stopped earlier. */
3312 if (cfun)
3313 n_deferred_constants++;
3314 return;
3317 output_constant_def_contents (symbol);
3320 /* Subroutine of output_constant_def_contents. Output the definition
3321 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3322 constant's alignment in bits. */
3324 static void
3325 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3327 HOST_WIDE_INT size;
3329 size = get_constant_size (exp);
3331 /* Do any machine/system dependent processing of the constant. */
3332 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3334 /* Output the value of EXP. */
3335 output_constant (exp, size, align, false);
3338 /* We must output the constant data referred to by SYMBOL; do so. */
3340 static void
3341 output_constant_def_contents (rtx symbol)
3343 tree decl = SYMBOL_REF_DECL (symbol);
3344 tree exp = DECL_INITIAL (decl);
3345 unsigned int align;
3346 bool asan_protected = false;
3348 /* Make sure any other constants whose addresses appear in EXP
3349 are assigned label numbers. */
3350 output_addressed_constants (exp);
3352 /* We are no longer deferring this constant. */
3353 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3355 if ((flag_sanitize & SANITIZE_ADDRESS)
3356 && TREE_CODE (exp) == STRING_CST
3357 && asan_protect_global (exp))
3359 asan_protected = true;
3360 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
3361 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
3364 /* If the constant is part of an object block, make sure that the
3365 decl has been positioned within its block, but do not write out
3366 its definition yet. output_object_blocks will do that later. */
3367 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3368 place_block_symbol (symbol);
3369 else
3371 align = DECL_ALIGN (decl);
3372 switch_to_section (get_constant_section (exp, align));
3373 if (align > BITS_PER_UNIT)
3374 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3375 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3376 if (asan_protected)
3378 HOST_WIDE_INT size = get_constant_size (exp);
3379 assemble_zeros (asan_red_zone_size (size));
3384 /* Look up EXP in the table of constant descriptors. Return the rtl
3385 if it has been emitted, else null. */
3388 lookup_constant_def (tree exp)
3390 struct constant_descriptor_tree *desc;
3391 struct constant_descriptor_tree key;
3393 key.value = exp;
3394 key.hash = const_hash_1 (exp);
3395 desc = (struct constant_descriptor_tree *)
3396 htab_find_with_hash (const_desc_htab, &key, key.hash);
3398 return (desc ? desc->rtl : NULL_RTX);
3401 /* Return a tree representing a reference to constant data in memory
3402 for the constant expression EXP.
3404 This is the counterpart of output_constant_def at the Tree level. */
3406 tree
3407 tree_output_constant_def (tree exp)
3409 struct constant_descriptor_tree *desc, key;
3410 void **loc;
3411 tree decl;
3413 /* Look up EXP in the table of constant descriptors. If we didn't find
3414 it, create a new one. */
3415 key.value = exp;
3416 key.hash = const_hash_1 (exp);
3417 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3419 desc = (struct constant_descriptor_tree *) *loc;
3420 if (desc == 0)
3422 desc = build_constant_desc (exp);
3423 desc->hash = key.hash;
3424 *loc = desc;
3427 decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3428 varpool_node::finalize_decl (decl);
3429 return decl;
3432 /* Used in the hash tables to avoid outputting the same constant
3433 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3434 are output once per function, not once per file. */
3435 /* ??? Only a few targets need per-function constant pools. Most
3436 can use one per-file pool. Should add a targetm bit to tell the
3437 difference. */
3439 struct GTY(()) rtx_constant_pool {
3440 /* Pointers to first and last constant in pool, as ordered by offset. */
3441 struct constant_descriptor_rtx *first;
3442 struct constant_descriptor_rtx *last;
3444 /* Hash facility for making memory-constants from constant rtl-expressions.
3445 It is used on RISC machines where immediate integer arguments and
3446 constant addresses are restricted so that such constants must be stored
3447 in memory. */
3448 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_htab;
3450 /* Current offset in constant pool (does not include any
3451 machine-specific header). */
3452 HOST_WIDE_INT offset;
3455 struct GTY((chain_next ("%h.next"))) constant_descriptor_rtx {
3456 struct constant_descriptor_rtx *next;
3457 rtx mem;
3458 rtx sym;
3459 rtx constant;
3460 HOST_WIDE_INT offset;
3461 hashval_t hash;
3462 enum machine_mode mode;
3463 unsigned int align;
3464 int labelno;
3465 int mark;
3468 /* Hash and compare functions for const_rtx_htab. */
3470 static hashval_t
3471 const_desc_rtx_hash (const void *ptr)
3473 const struct constant_descriptor_rtx *const desc
3474 = (const struct constant_descriptor_rtx *) ptr;
3475 return desc->hash;
3478 static int
3479 const_desc_rtx_eq (const void *a, const void *b)
3481 const struct constant_descriptor_rtx *const x
3482 = (const struct constant_descriptor_rtx *) a;
3483 const struct constant_descriptor_rtx *const y
3484 = (const struct constant_descriptor_rtx *) b;
3486 if (x->mode != y->mode)
3487 return 0;
3488 return rtx_equal_p (x->constant, y->constant);
3491 /* Hash one component of a constant. */
3493 static hashval_t
3494 const_rtx_hash_1 (const_rtx x)
3496 unsigned HOST_WIDE_INT hwi;
3497 enum machine_mode mode;
3498 enum rtx_code code;
3499 hashval_t h;
3500 int i;
3502 code = GET_CODE (x);
3503 mode = GET_MODE (x);
3504 h = (hashval_t) code * 1048573 + mode;
3506 switch (code)
3508 case CONST_INT:
3509 hwi = INTVAL (x);
3511 fold_hwi:
3513 int shift = sizeof (hashval_t) * CHAR_BIT;
3514 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3516 h ^= (hashval_t) hwi;
3517 for (i = 1; i < n; ++i)
3519 hwi >>= shift;
3520 h ^= (hashval_t) hwi;
3523 break;
3525 case CONST_WIDE_INT:
3526 hwi = GET_MODE_PRECISION (mode);
3528 for (i = 0; i < CONST_WIDE_INT_NUNITS (x); i++)
3529 hwi ^= CONST_WIDE_INT_ELT (x, i);
3530 goto fold_hwi;
3533 case CONST_DOUBLE:
3534 if (TARGET_SUPPORTS_WIDE_INT == 0 && mode == VOIDmode)
3536 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3537 goto fold_hwi;
3539 else
3540 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3541 break;
3543 case CONST_FIXED:
3544 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3545 break;
3547 case SYMBOL_REF:
3548 h ^= htab_hash_string (XSTR (x, 0));
3549 break;
3551 case LABEL_REF:
3552 h = h * 251 + CODE_LABEL_NUMBER (LABEL_REF_LABEL (x));
3553 break;
3555 case UNSPEC:
3556 case UNSPEC_VOLATILE:
3557 h = h * 251 + XINT (x, 1);
3558 break;
3560 default:
3561 break;
3564 return h;
3567 /* Compute a hash value for X, which should be a constant. */
3569 static hashval_t
3570 const_rtx_hash (rtx x)
3572 hashval_t h = 0;
3573 subrtx_iterator::array_type array;
3574 FOR_EACH_SUBRTX (iter, array, x, ALL)
3575 h = h * 509 + const_rtx_hash_1 (*iter);
3576 return h;
3580 /* Create and return a new rtx constant pool. */
3582 static struct rtx_constant_pool *
3583 create_constant_pool (void)
3585 struct rtx_constant_pool *pool;
3587 pool = ggc_alloc<rtx_constant_pool> ();
3588 pool->const_rtx_htab = htab_create_ggc (31, const_desc_rtx_hash,
3589 const_desc_rtx_eq, NULL);
3590 pool->first = NULL;
3591 pool->last = NULL;
3592 pool->offset = 0;
3593 return pool;
3596 /* Initialize constant pool hashing for a new function. */
3598 void
3599 init_varasm_status (void)
3601 crtl->varasm.pool = create_constant_pool ();
3602 crtl->varasm.deferred_constants = 0;
3605 /* Given a MINUS expression, simplify it if both sides
3606 include the same symbol. */
3609 simplify_subtraction (rtx x)
3611 rtx r = simplify_rtx (x);
3612 return r ? r : x;
3615 /* Given a constant rtx X, make (or find) a memory constant for its value
3616 and return a MEM rtx to refer to it in memory. */
3619 force_const_mem (enum machine_mode mode, rtx x)
3621 struct constant_descriptor_rtx *desc, tmp;
3622 struct rtx_constant_pool *pool;
3623 char label[256];
3624 rtx def, symbol;
3625 hashval_t hash;
3626 unsigned int align;
3627 void **slot;
3629 /* If we're not allowed to drop X into the constant pool, don't. */
3630 if (targetm.cannot_force_const_mem (mode, x))
3631 return NULL_RTX;
3633 /* Record that this function has used a constant pool entry. */
3634 crtl->uses_const_pool = 1;
3636 /* Decide which pool to use. */
3637 pool = (targetm.use_blocks_for_constant_p (mode, x)
3638 ? shared_constant_pool
3639 : crtl->varasm.pool);
3641 /* Lookup the value in the hashtable. */
3642 tmp.constant = x;
3643 tmp.mode = mode;
3644 hash = const_rtx_hash (x);
3645 slot = htab_find_slot_with_hash (pool->const_rtx_htab, &tmp, hash, INSERT);
3646 desc = (struct constant_descriptor_rtx *) *slot;
3648 /* If the constant was already present, return its memory. */
3649 if (desc)
3650 return copy_rtx (desc->mem);
3652 /* Otherwise, create a new descriptor. */
3653 desc = ggc_alloc<constant_descriptor_rtx> ();
3654 *slot = desc;
3656 /* Align the location counter as required by EXP's data type. */
3657 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3658 #ifdef CONSTANT_ALIGNMENT
3660 tree type = lang_hooks.types.type_for_mode (mode, 0);
3661 if (type != NULL_TREE)
3662 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3664 #endif
3666 pool->offset += (align / BITS_PER_UNIT) - 1;
3667 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3669 desc->next = NULL;
3670 desc->constant = copy_rtx (tmp.constant);
3671 desc->offset = pool->offset;
3672 desc->hash = hash;
3673 desc->mode = mode;
3674 desc->align = align;
3675 desc->labelno = const_labelno;
3676 desc->mark = 0;
3678 pool->offset += GET_MODE_SIZE (mode);
3679 if (pool->last)
3680 pool->last->next = desc;
3681 else
3682 pool->first = pool->last = desc;
3683 pool->last = desc;
3685 /* Create a string containing the label name, in LABEL. */
3686 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3687 ++const_labelno;
3689 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3690 the constants pool. */
3691 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3693 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3694 symbol = create_block_symbol (ggc_strdup (label),
3695 get_block_for_section (sect), -1);
3697 else
3698 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3699 desc->sym = symbol;
3700 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3701 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3702 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3704 /* Construct the MEM. */
3705 desc->mem = def = gen_const_mem (mode, symbol);
3706 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3707 set_mem_align (def, align);
3709 /* If we're dropping a label to the constant pool, make sure we
3710 don't delete it. */
3711 if (GET_CODE (x) == LABEL_REF)
3712 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3714 return copy_rtx (def);
3717 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3720 get_pool_constant (const_rtx addr)
3722 return SYMBOL_REF_CONSTANT (addr)->constant;
3725 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3726 and whether it has been output or not. */
3729 get_pool_constant_mark (rtx addr, bool *pmarked)
3731 struct constant_descriptor_rtx *desc;
3733 desc = SYMBOL_REF_CONSTANT (addr);
3734 *pmarked = (desc->mark != 0);
3735 return desc->constant;
3738 /* Similar, return the mode. */
3740 enum machine_mode
3741 get_pool_mode (const_rtx addr)
3743 return SYMBOL_REF_CONSTANT (addr)->mode;
3746 /* Return the size of the constant pool. */
3749 get_pool_size (void)
3751 return crtl->varasm.pool->offset;
3754 /* Worker function for output_constant_pool_1. Emit assembly for X
3755 in MODE with known alignment ALIGN. */
3757 static void
3758 output_constant_pool_2 (enum machine_mode mode, rtx x, unsigned int align)
3760 switch (GET_MODE_CLASS (mode))
3762 case MODE_FLOAT:
3763 case MODE_DECIMAL_FLOAT:
3765 REAL_VALUE_TYPE r;
3767 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3768 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3769 assemble_real (r, mode, align);
3770 break;
3773 case MODE_INT:
3774 case MODE_PARTIAL_INT:
3775 case MODE_FRACT:
3776 case MODE_UFRACT:
3777 case MODE_ACCUM:
3778 case MODE_UACCUM:
3779 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3780 break;
3782 case MODE_VECTOR_FLOAT:
3783 case MODE_VECTOR_INT:
3784 case MODE_VECTOR_FRACT:
3785 case MODE_VECTOR_UFRACT:
3786 case MODE_VECTOR_ACCUM:
3787 case MODE_VECTOR_UACCUM:
3789 int i, units;
3790 enum machine_mode submode = GET_MODE_INNER (mode);
3791 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3793 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3794 units = CONST_VECTOR_NUNITS (x);
3796 for (i = 0; i < units; i++)
3798 rtx elt = CONST_VECTOR_ELT (x, i);
3799 output_constant_pool_2 (submode, elt, i ? subalign : align);
3802 break;
3804 default:
3805 gcc_unreachable ();
3809 /* Worker function for output_constant_pool. Emit constant DESC,
3810 giving it ALIGN bits of alignment. */
3812 static void
3813 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3814 unsigned int align)
3816 rtx x, tmp;
3818 x = desc->constant;
3820 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3821 whose CODE_LABEL has been deleted. This can occur if a jump table
3822 is eliminated by optimization. If so, write a constant of zero
3823 instead. Note that this can also happen by turning the
3824 CODE_LABEL into a NOTE. */
3825 /* ??? This seems completely and utterly wrong. Certainly it's
3826 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3827 functioning even with rtx_insn::deleted and friends. */
3829 tmp = x;
3830 switch (GET_CODE (tmp))
3832 case CONST:
3833 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3834 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
3835 break;
3836 tmp = XEXP (XEXP (tmp, 0), 0);
3837 /* FALLTHRU */
3839 case LABEL_REF:
3840 tmp = LABEL_REF_LABEL (tmp);
3841 gcc_assert (!as_a<rtx_insn *> (tmp)->deleted ());
3842 gcc_assert (!NOTE_P (tmp)
3843 || NOTE_KIND (tmp) != NOTE_INSN_DELETED);
3844 break;
3846 default:
3847 break;
3850 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3851 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3852 align, desc->labelno, done);
3853 #endif
3855 assemble_align (align);
3857 /* Output the label. */
3858 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3860 /* Output the data. */
3861 output_constant_pool_2 (desc->mode, x, align);
3863 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3864 sections have proper size. */
3865 if (align > GET_MODE_BITSIZE (desc->mode)
3866 && in_section
3867 && (in_section->common.flags & SECTION_MERGE))
3868 assemble_align (align);
3870 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3871 done:
3872 #endif
3873 return;
3876 /* Mark all constants that are referenced by SYMBOL_REFs in X.
3877 Emit referenced deferred strings. */
3879 static void
3880 mark_constants_in_pattern (rtx insn)
3882 subrtx_iterator::array_type array;
3883 FOR_EACH_SUBRTX (iter, array, PATTERN (insn), ALL)
3885 const_rtx x = *iter;
3886 if (GET_CODE (x) == SYMBOL_REF)
3888 if (CONSTANT_POOL_ADDRESS_P (x))
3890 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
3891 if (desc->mark == 0)
3893 desc->mark = 1;
3894 iter.substitute (desc->constant);
3897 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3899 tree decl = SYMBOL_REF_DECL (x);
3900 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
3902 n_deferred_constants--;
3903 output_constant_def_contents (CONST_CAST_RTX (x));
3910 /* Look through appropriate parts of INSN, marking all entries in the
3911 constant pool which are actually being used. Entries that are only
3912 referenced by other constants are also marked as used. Emit
3913 deferred strings that are used. */
3915 static void
3916 mark_constants (rtx_insn *insn)
3918 if (!INSN_P (insn))
3919 return;
3921 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3922 insns, not any notes that may be attached. We don't want to mark
3923 a constant just because it happens to appear in a REG_EQUIV note. */
3924 if (rtx_sequence *seq = dyn_cast <rtx_sequence *> (PATTERN (insn)))
3926 int i, n = seq->len ();
3927 for (i = 0; i < n; ++i)
3929 rtx subinsn = seq->element (i);
3930 if (INSN_P (subinsn))
3931 mark_constants_in_pattern (subinsn);
3934 else
3935 mark_constants_in_pattern (insn);
3938 /* Look through the instructions for this function, and mark all the
3939 entries in POOL which are actually being used. Emit deferred constants
3940 which have indeed been used. */
3942 static void
3943 mark_constant_pool (void)
3945 rtx_insn *insn;
3947 if (!crtl->uses_const_pool && n_deferred_constants == 0)
3948 return;
3950 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3951 mark_constants (insn);
3954 /* Write all the constants in POOL. */
3956 static void
3957 output_constant_pool_contents (struct rtx_constant_pool *pool)
3959 struct constant_descriptor_rtx *desc;
3961 for (desc = pool->first; desc ; desc = desc->next)
3962 if (desc->mark)
3964 /* If the constant is part of an object_block, make sure that
3965 the constant has been positioned within its block, but do not
3966 write out its definition yet. output_object_blocks will do
3967 that later. */
3968 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
3969 && SYMBOL_REF_BLOCK (desc->sym))
3970 place_block_symbol (desc->sym);
3971 else
3973 switch_to_section (targetm.asm_out.select_rtx_section
3974 (desc->mode, desc->constant, desc->align));
3975 output_constant_pool_1 (desc, desc->align);
3980 /* Mark all constants that are used in the current function, then write
3981 out the function's private constant pool. */
3983 static void
3984 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
3985 tree fndecl ATTRIBUTE_UNUSED)
3987 struct rtx_constant_pool *pool = crtl->varasm.pool;
3989 /* It is possible for gcc to call force_const_mem and then to later
3990 discard the instructions which refer to the constant. In such a
3991 case we do not need to output the constant. */
3992 mark_constant_pool ();
3994 #ifdef ASM_OUTPUT_POOL_PROLOGUE
3995 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
3996 #endif
3998 output_constant_pool_contents (pool);
4000 #ifdef ASM_OUTPUT_POOL_EPILOGUE
4001 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
4002 #endif
4005 /* Write the contents of the shared constant pool. */
4007 void
4008 output_shared_constant_pool (void)
4010 output_constant_pool_contents (shared_constant_pool);
4013 /* Determine what kind of relocations EXP may need. */
4016 compute_reloc_for_constant (tree exp)
4018 int reloc = 0, reloc2;
4019 tree tem;
4021 switch (TREE_CODE (exp))
4023 case ADDR_EXPR:
4024 case FDESC_EXPR:
4025 /* Go inside any operations that get_inner_reference can handle and see
4026 if what's inside is a constant: no need to do anything here for
4027 addresses of variables or functions. */
4028 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4029 tem = TREE_OPERAND (tem, 0))
4032 if (TREE_CODE (tem) == MEM_REF
4033 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4035 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4036 break;
4039 if (!targetm.binds_local_p (tem))
4040 reloc |= 2;
4041 else
4042 reloc |= 1;
4043 break;
4045 case PLUS_EXPR:
4046 case POINTER_PLUS_EXPR:
4047 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4048 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4049 break;
4051 case MINUS_EXPR:
4052 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4053 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4054 /* The difference of two local labels is computable at link time. */
4055 if (reloc == 1 && reloc2 == 1)
4056 reloc = 0;
4057 else
4058 reloc |= reloc2;
4059 break;
4061 CASE_CONVERT:
4062 case VIEW_CONVERT_EXPR:
4063 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4064 break;
4066 case CONSTRUCTOR:
4068 unsigned HOST_WIDE_INT idx;
4069 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4070 if (tem != 0)
4071 reloc |= compute_reloc_for_constant (tem);
4073 break;
4075 default:
4076 break;
4078 return reloc;
4081 /* Find all the constants whose addresses are referenced inside of EXP,
4082 and make sure assembler code with a label has been output for each one.
4083 Indicate whether an ADDR_EXPR has been encountered. */
4085 static void
4086 output_addressed_constants (tree exp)
4088 tree tem;
4090 switch (TREE_CODE (exp))
4092 case ADDR_EXPR:
4093 case FDESC_EXPR:
4094 /* Go inside any operations that get_inner_reference can handle and see
4095 if what's inside is a constant: no need to do anything here for
4096 addresses of variables or functions. */
4097 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4098 tem = TREE_OPERAND (tem, 0))
4101 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4102 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4103 tem = DECL_INITIAL (tem);
4105 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4106 output_constant_def (tem, 0);
4108 if (TREE_CODE (tem) == MEM_REF)
4109 output_addressed_constants (TREE_OPERAND (tem, 0));
4110 break;
4112 case PLUS_EXPR:
4113 case POINTER_PLUS_EXPR:
4114 case MINUS_EXPR:
4115 output_addressed_constants (TREE_OPERAND (exp, 1));
4116 /* Fall through. */
4118 CASE_CONVERT:
4119 case VIEW_CONVERT_EXPR:
4120 output_addressed_constants (TREE_OPERAND (exp, 0));
4121 break;
4123 case CONSTRUCTOR:
4125 unsigned HOST_WIDE_INT idx;
4126 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4127 if (tem != 0)
4128 output_addressed_constants (tem);
4130 break;
4132 default:
4133 break;
4137 /* Whether a constructor CTOR is a valid static constant initializer if all
4138 its elements are. This used to be internal to initializer_constant_valid_p
4139 and has been exposed to let other functions like categorize_ctor_elements
4140 evaluate the property while walking a constructor for other purposes. */
4142 bool
4143 constructor_static_from_elts_p (const_tree ctor)
4145 return (TREE_CONSTANT (ctor)
4146 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4147 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4148 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4151 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4152 tree *cache);
4154 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4155 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4156 which are valid when ENDTYPE is an integer of any size; in
4157 particular, this does not accept a pointer minus a constant. This
4158 returns null_pointer_node if the VALUE is an absolute constant
4159 which can be used to initialize a static variable. Otherwise it
4160 returns NULL. */
4162 static tree
4163 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4165 tree op0, op1;
4167 if (!INTEGRAL_TYPE_P (endtype))
4168 return NULL_TREE;
4170 op0 = TREE_OPERAND (value, 0);
4171 op1 = TREE_OPERAND (value, 1);
4173 /* Like STRIP_NOPS except allow the operand mode to widen. This
4174 works around a feature of fold that simplifies (int)(p1 - p2) to
4175 ((int)p1 - (int)p2) under the theory that the narrower operation
4176 is cheaper. */
4178 while (CONVERT_EXPR_P (op0)
4179 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4181 tree inner = TREE_OPERAND (op0, 0);
4182 if (inner == error_mark_node
4183 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4184 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
4185 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4186 break;
4187 op0 = inner;
4190 while (CONVERT_EXPR_P (op1)
4191 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4193 tree inner = TREE_OPERAND (op1, 0);
4194 if (inner == error_mark_node
4195 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4196 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
4197 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4198 break;
4199 op1 = inner;
4202 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4203 if (!op0)
4204 return NULL_TREE;
4206 op1 = initializer_constant_valid_p_1 (op1, endtype,
4207 cache ? cache + 2 : NULL);
4208 /* Both initializers must be known. */
4209 if (op1)
4211 if (op0 == op1
4212 && (op0 == null_pointer_node
4213 || TREE_CODE (value) == MINUS_EXPR))
4214 return null_pointer_node;
4216 /* Support differences between labels. */
4217 if (TREE_CODE (op0) == LABEL_DECL
4218 && TREE_CODE (op1) == LABEL_DECL)
4219 return null_pointer_node;
4221 if (TREE_CODE (op0) == STRING_CST
4222 && TREE_CODE (op1) == STRING_CST
4223 && operand_equal_p (op0, op1, 1))
4224 return null_pointer_node;
4227 return NULL_TREE;
4230 /* Helper function of initializer_constant_valid_p.
4231 Return nonzero if VALUE is a valid constant-valued expression
4232 for use in initializing a static variable; one that can be an
4233 element of a "constant" initializer.
4235 Return null_pointer_node if the value is absolute;
4236 if it is relocatable, return the variable that determines the relocation.
4237 We assume that VALUE has been folded as much as possible;
4238 therefore, we do not need to check for such things as
4239 arithmetic-combinations of integers.
4241 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4243 static tree
4244 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4246 tree ret;
4248 switch (TREE_CODE (value))
4250 case CONSTRUCTOR:
4251 if (constructor_static_from_elts_p (value))
4253 unsigned HOST_WIDE_INT idx;
4254 tree elt;
4255 bool absolute = true;
4257 if (cache && cache[0] == value)
4258 return cache[1];
4259 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4261 tree reloc;
4262 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4263 NULL);
4264 if (!reloc)
4266 if (cache)
4268 cache[0] = value;
4269 cache[1] = NULL_TREE;
4271 return NULL_TREE;
4273 if (reloc != null_pointer_node)
4274 absolute = false;
4276 /* For a non-absolute relocation, there is no single
4277 variable that can be "the variable that determines the
4278 relocation." */
4279 if (cache)
4281 cache[0] = value;
4282 cache[1] = absolute ? null_pointer_node : error_mark_node;
4284 return absolute ? null_pointer_node : error_mark_node;
4287 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4289 case INTEGER_CST:
4290 case VECTOR_CST:
4291 case REAL_CST:
4292 case FIXED_CST:
4293 case STRING_CST:
4294 case COMPLEX_CST:
4295 return null_pointer_node;
4297 case ADDR_EXPR:
4298 case FDESC_EXPR:
4300 tree op0 = staticp (TREE_OPERAND (value, 0));
4301 if (op0)
4303 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4304 to be a constant, this is old-skool offsetof-like nonsense. */
4305 if (TREE_CODE (op0) == INDIRECT_REF
4306 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4307 return null_pointer_node;
4308 /* Taking the address of a nested function involves a trampoline,
4309 unless we don't need or want one. */
4310 if (TREE_CODE (op0) == FUNCTION_DECL
4311 && DECL_STATIC_CHAIN (op0)
4312 && !TREE_NO_TRAMPOLINE (value))
4313 return NULL_TREE;
4314 /* "&{...}" requires a temporary to hold the constructed
4315 object. */
4316 if (TREE_CODE (op0) == CONSTRUCTOR)
4317 return NULL_TREE;
4319 return op0;
4322 case NON_LVALUE_EXPR:
4323 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4324 endtype, cache);
4326 case VIEW_CONVERT_EXPR:
4328 tree src = TREE_OPERAND (value, 0);
4329 tree src_type = TREE_TYPE (src);
4330 tree dest_type = TREE_TYPE (value);
4332 /* Allow view-conversions from aggregate to non-aggregate type only
4333 if the bit pattern is fully preserved afterwards; otherwise, the
4334 RTL expander won't be able to apply a subsequent transformation
4335 to the underlying constructor. */
4336 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4338 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4339 return initializer_constant_valid_p_1 (src, endtype, cache);
4340 else
4341 return NULL_TREE;
4344 /* Allow all other kinds of view-conversion. */
4345 return initializer_constant_valid_p_1 (src, endtype, cache);
4348 CASE_CONVERT:
4350 tree src = TREE_OPERAND (value, 0);
4351 tree src_type = TREE_TYPE (src);
4352 tree dest_type = TREE_TYPE (value);
4354 /* Allow conversions between pointer types, floating-point
4355 types, and offset types. */
4356 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4357 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4358 || (TREE_CODE (dest_type) == OFFSET_TYPE
4359 && TREE_CODE (src_type) == OFFSET_TYPE))
4360 return initializer_constant_valid_p_1 (src, endtype, cache);
4362 /* Allow length-preserving conversions between integer types. */
4363 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4364 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4365 return initializer_constant_valid_p_1 (src, endtype, cache);
4367 /* Allow conversions between other integer types only if
4368 explicit value. */
4369 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type))
4371 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4372 if (inner == null_pointer_node)
4373 return null_pointer_node;
4374 break;
4377 /* Allow (int) &foo provided int is as wide as a pointer. */
4378 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4379 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4380 return initializer_constant_valid_p_1 (src, endtype, cache);
4382 /* Likewise conversions from int to pointers, but also allow
4383 conversions from 0. */
4384 if ((POINTER_TYPE_P (dest_type)
4385 || TREE_CODE (dest_type) == OFFSET_TYPE)
4386 && INTEGRAL_TYPE_P (src_type))
4388 if (TREE_CODE (src) == INTEGER_CST
4389 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4390 return null_pointer_node;
4391 if (integer_zerop (src))
4392 return null_pointer_node;
4393 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4394 return initializer_constant_valid_p_1 (src, endtype, cache);
4397 /* Allow conversions to struct or union types if the value
4398 inside is okay. */
4399 if (TREE_CODE (dest_type) == RECORD_TYPE
4400 || TREE_CODE (dest_type) == UNION_TYPE)
4401 return initializer_constant_valid_p_1 (src, endtype, cache);
4403 break;
4405 case POINTER_PLUS_EXPR:
4406 case PLUS_EXPR:
4407 /* Any valid floating-point constants will have been folded by now;
4408 with -frounding-math we hit this with addition of two constants. */
4409 if (TREE_CODE (endtype) == REAL_TYPE)
4410 return NULL_TREE;
4411 if (cache && cache[0] == value)
4412 return cache[1];
4413 if (! INTEGRAL_TYPE_P (endtype)
4414 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4416 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4417 tree valid0
4418 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4419 endtype, ncache);
4420 tree valid1
4421 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4422 endtype, ncache + 2);
4423 /* If either term is absolute, use the other term's relocation. */
4424 if (valid0 == null_pointer_node)
4425 ret = valid1;
4426 else if (valid1 == null_pointer_node)
4427 ret = valid0;
4428 /* Support narrowing pointer differences. */
4429 else
4430 ret = narrowing_initializer_constant_valid_p (value, endtype,
4431 ncache);
4433 else
4434 /* Support narrowing pointer differences. */
4435 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4436 if (cache)
4438 cache[0] = value;
4439 cache[1] = ret;
4441 return ret;
4443 case MINUS_EXPR:
4444 if (TREE_CODE (endtype) == REAL_TYPE)
4445 return NULL_TREE;
4446 if (cache && cache[0] == value)
4447 return cache[1];
4448 if (! INTEGRAL_TYPE_P (endtype)
4449 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4451 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4452 tree valid0
4453 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4454 endtype, ncache);
4455 tree valid1
4456 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4457 endtype, ncache + 2);
4458 /* Win if second argument is absolute. */
4459 if (valid1 == null_pointer_node)
4460 ret = valid0;
4461 /* Win if both arguments have the same relocation.
4462 Then the value is absolute. */
4463 else if (valid0 == valid1 && valid0 != 0)
4464 ret = null_pointer_node;
4465 /* Since GCC guarantees that string constants are unique in the
4466 generated code, a subtraction between two copies of the same
4467 constant string is absolute. */
4468 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4469 && valid1 && TREE_CODE (valid1) == STRING_CST
4470 && operand_equal_p (valid0, valid1, 1))
4471 ret = null_pointer_node;
4472 /* Support narrowing differences. */
4473 else
4474 ret = narrowing_initializer_constant_valid_p (value, endtype,
4475 ncache);
4477 else
4478 /* Support narrowing differences. */
4479 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4480 if (cache)
4482 cache[0] = value;
4483 cache[1] = ret;
4485 return ret;
4487 default:
4488 break;
4491 return NULL_TREE;
4494 /* Return nonzero if VALUE is a valid constant-valued expression
4495 for use in initializing a static variable; one that can be an
4496 element of a "constant" initializer.
4498 Return null_pointer_node if the value is absolute;
4499 if it is relocatable, return the variable that determines the relocation.
4500 We assume that VALUE has been folded as much as possible;
4501 therefore, we do not need to check for such things as
4502 arithmetic-combinations of integers. */
4503 tree
4504 initializer_constant_valid_p (tree value, tree endtype)
4506 return initializer_constant_valid_p_1 (value, endtype, NULL);
4509 /* Return true if VALUE is a valid constant-valued expression
4510 for use in initializing a static bit-field; one that can be
4511 an element of a "constant" initializer. */
4513 bool
4514 initializer_constant_valid_for_bitfield_p (tree value)
4516 /* For bitfields we support integer constants or possibly nested aggregates
4517 of such. */
4518 switch (TREE_CODE (value))
4520 case CONSTRUCTOR:
4522 unsigned HOST_WIDE_INT idx;
4523 tree elt;
4525 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4526 if (!initializer_constant_valid_for_bitfield_p (elt))
4527 return false;
4528 return true;
4531 case INTEGER_CST:
4532 case REAL_CST:
4533 return true;
4535 case VIEW_CONVERT_EXPR:
4536 case NON_LVALUE_EXPR:
4537 return
4538 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4540 default:
4541 break;
4544 return false;
4547 /* output_constructor outer state of relevance in recursive calls, typically
4548 for nested aggregate bitfields. */
4550 typedef struct {
4551 unsigned int bit_offset; /* current position in ... */
4552 int byte; /* ... the outer byte buffer. */
4553 } oc_outer_state;
4555 static unsigned HOST_WIDE_INT
4556 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int, bool,
4557 oc_outer_state *);
4559 /* Output assembler code for constant EXP, with no label.
4560 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4561 Assumes output_addressed_constants has been done on EXP already.
4563 Generate at least SIZE bytes of assembler data, padding at the end
4564 with zeros if necessary. SIZE must always be specified. The returned
4565 value is the actual number of bytes of assembler data generated, which
4566 may be bigger than SIZE if the object contains a variable length field.
4568 SIZE is important for structure constructors,
4569 since trailing members may have been omitted from the constructor.
4570 It is also important for initialization of arrays from string constants
4571 since the full length of the string constant might not be wanted.
4572 It is also needed for initialization of unions, where the initializer's
4573 type is just one member, and that may not be as long as the union.
4575 There a case in which we would fail to output exactly SIZE bytes:
4576 for a structure constructor that wants to produce more than SIZE bytes.
4577 But such constructors will never be generated for any possible input.
4579 ALIGN is the alignment of the data in bits.
4581 If REVERSE is true, EXP is interpreted in reverse storage order wrt the
4582 target order. */
4584 static unsigned HOST_WIDE_INT
4585 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align,
4586 bool reverse)
4588 enum tree_code code;
4589 unsigned HOST_WIDE_INT thissize;
4591 if (size == 0 || flag_syntax_only)
4592 return size;
4594 /* See if we're trying to initialize a pointer in a non-default mode
4595 to the address of some declaration somewhere. If the target says
4596 the mode is valid for pointers, assume the target has a way of
4597 resolving it. */
4598 if (TREE_CODE (exp) == NOP_EXPR
4599 && POINTER_TYPE_P (TREE_TYPE (exp))
4600 && targetm.addr_space.valid_pointer_mode
4601 (TYPE_MODE (TREE_TYPE (exp)),
4602 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4604 tree saved_type = TREE_TYPE (exp);
4606 /* Peel off any intermediate conversions-to-pointer for valid
4607 pointer modes. */
4608 while (TREE_CODE (exp) == NOP_EXPR
4609 && POINTER_TYPE_P (TREE_TYPE (exp))
4610 && targetm.addr_space.valid_pointer_mode
4611 (TYPE_MODE (TREE_TYPE (exp)),
4612 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4613 exp = TREE_OPERAND (exp, 0);
4615 /* If what we're left with is the address of something, we can
4616 convert the address to the final type and output it that
4617 way. */
4618 if (TREE_CODE (exp) == ADDR_EXPR)
4619 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4620 /* Likewise for constant ints. */
4621 else if (TREE_CODE (exp) == INTEGER_CST)
4622 exp = wide_int_to_tree (saved_type, exp);
4626 /* Eliminate any conversions since we'll be outputting the underlying
4627 constant. */
4628 while (CONVERT_EXPR_P (exp)
4629 || TREE_CODE (exp) == NON_LVALUE_EXPR
4630 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4632 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4633 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4635 /* Make sure eliminating the conversion is really a no-op, except with
4636 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4637 union types to allow for Ada unchecked unions. */
4638 if (type_size > op_size
4639 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4640 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4641 /* Keep the conversion. */
4642 break;
4643 else
4644 exp = TREE_OPERAND (exp, 0);
4647 code = TREE_CODE (TREE_TYPE (exp));
4648 thissize = int_size_in_bytes (TREE_TYPE (exp));
4650 /* Allow a constructor with no elements for any data type.
4651 This means to fill the space with zeros. */
4652 if (TREE_CODE (exp) == CONSTRUCTOR
4653 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4655 assemble_zeros (size);
4656 return size;
4659 if (TREE_CODE (exp) == FDESC_EXPR)
4661 #ifdef ASM_OUTPUT_FDESC
4662 HOST_WIDE_INT part = tree_to_shwi (TREE_OPERAND (exp, 1));
4663 tree decl = TREE_OPERAND (exp, 0);
4664 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4665 #else
4666 gcc_unreachable ();
4667 #endif
4668 return size;
4671 /* Now output the underlying data. If we've handling the padding, return.
4672 Otherwise, break and ensure SIZE is the size written. */
4673 switch (code)
4675 case BOOLEAN_TYPE:
4676 case INTEGER_TYPE:
4677 case ENUMERAL_TYPE:
4678 case POINTER_TYPE:
4679 case REFERENCE_TYPE:
4680 case OFFSET_TYPE:
4681 case FIXED_POINT_TYPE:
4682 case NULLPTR_TYPE:
4683 if (reverse)
4684 exp = fold_flip_storage_order (exp);
4685 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
4686 EXPAND_INITIALIZER),
4687 MIN (size, thissize), align, 0))
4688 error ("initializer for integer/fixed-point value is too complicated");
4689 break;
4691 case REAL_TYPE:
4692 if (TREE_CODE (exp) != REAL_CST)
4693 error ("initializer for floating value is not a floating constant");
4694 else
4696 if (reverse)
4697 exp = fold_flip_storage_order (exp);
4698 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)),
4699 align);
4701 break;
4703 case COMPLEX_TYPE:
4704 output_constant (TREE_REALPART (exp), thissize / 2, align, reverse);
4705 output_constant (TREE_IMAGPART (exp), thissize / 2,
4706 min_align (align, BITS_PER_UNIT * (thissize / 2)),
4707 reverse);
4708 break;
4710 case ARRAY_TYPE:
4711 case VECTOR_TYPE:
4712 switch (TREE_CODE (exp))
4714 case CONSTRUCTOR:
4715 return output_constructor (exp, size, align, reverse, NULL);
4716 case STRING_CST:
4717 thissize
4718 = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4719 assemble_string (TREE_STRING_POINTER (exp), thissize);
4720 break;
4721 case VECTOR_CST:
4723 enum machine_mode inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4724 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4725 int elt_size = GET_MODE_SIZE (inner);
4726 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align,
4727 reverse);
4728 thissize = elt_size;
4729 for (unsigned int i = 1; i < VECTOR_CST_NELTS (exp); i++)
4731 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign,
4732 reverse);
4733 thissize += elt_size;
4735 break;
4737 default:
4738 gcc_unreachable ();
4740 break;
4742 case RECORD_TYPE:
4743 case UNION_TYPE:
4744 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4745 return output_constructor (exp, size, align, reverse, NULL);
4747 case ERROR_MARK:
4748 return 0;
4750 default:
4751 gcc_unreachable ();
4754 if (size > thissize)
4755 assemble_zeros (size - thissize);
4757 return size;
4760 /* Subroutine of output_constructor, used for computing the size of
4761 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4762 type with an unspecified upper bound. */
4764 static unsigned HOST_WIDE_INT
4765 array_size_for_constructor (tree val)
4767 tree max_index;
4768 unsigned HOST_WIDE_INT cnt;
4769 tree index, value, tmp;
4770 offset_int i;
4772 /* This code used to attempt to handle string constants that are not
4773 arrays of single-bytes, but nothing else does, so there's no point in
4774 doing it here. */
4775 if (TREE_CODE (val) == STRING_CST)
4776 return TREE_STRING_LENGTH (val);
4778 max_index = NULL_TREE;
4779 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
4781 if (TREE_CODE (index) == RANGE_EXPR)
4782 index = TREE_OPERAND (index, 1);
4783 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
4784 max_index = index;
4787 if (max_index == NULL_TREE)
4788 return 0;
4790 /* Compute the total number of array elements. */
4791 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
4792 i = wi::to_offset (max_index) - wi::to_offset (tmp) + 1;
4794 /* Multiply by the array element unit size to find number of bytes. */
4795 i *= wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
4797 gcc_assert (wi::fits_uhwi_p (i));
4798 return i.to_uhwi ();
4801 /* Other datastructures + helpers for output_constructor. */
4803 /* output_constructor local state to support interaction with helpers. */
4805 typedef struct {
4807 /* Received arguments. */
4808 tree exp; /* Constructor expression. */
4809 tree type; /* Type of constructor expression. */
4810 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */
4811 unsigned int align; /* Known initial alignment. */
4812 tree min_index; /* Lower bound if specified for an array. */
4814 /* Output processing state. */
4815 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */
4816 int byte; /* Part of a bitfield byte yet to be output. */
4817 int last_relative_index; /* Implicit or explicit index of the last
4818 array element output within a bitfield. */
4819 bool byte_buffer_in_use; /* Whether BYTE is in use. */
4820 bool reverse; /* Whether reverse storage order is in use. */
4822 /* Current element. */
4823 tree field; /* Current field decl in a record. */
4824 tree val; /* Current element value. */
4825 tree index; /* Current element index. */
4827 } oc_local_state;
4829 /* Helper for output_constructor. From the current LOCAL state, output a
4830 RANGE_EXPR element. */
4832 static void
4833 output_constructor_array_range (oc_local_state *local)
4835 unsigned HOST_WIDE_INT fieldsize
4836 = int_size_in_bytes (TREE_TYPE (local->type));
4838 HOST_WIDE_INT lo_index
4839 = tree_to_shwi (TREE_OPERAND (local->index, 0));
4840 HOST_WIDE_INT hi_index
4841 = tree_to_shwi (TREE_OPERAND (local->index, 1));
4842 HOST_WIDE_INT index;
4844 unsigned int align2
4845 = min_align (local->align, fieldsize * BITS_PER_UNIT);
4847 for (index = lo_index; index <= hi_index; index++)
4849 /* Output the element's initial value. */
4850 if (local->val == NULL_TREE)
4851 assemble_zeros (fieldsize);
4852 else
4853 fieldsize
4854 = output_constant (local->val, fieldsize, align2, local->reverse);
4856 /* Count its size. */
4857 local->total_bytes += fieldsize;
4861 /* Helper for output_constructor. From the current LOCAL state, output a
4862 field element that is not true bitfield or part of an outer one. */
4864 static void
4865 output_constructor_regular_field (oc_local_state *local)
4867 /* Field size and position. Since this structure is static, we know the
4868 positions are constant. */
4869 unsigned HOST_WIDE_INT fieldsize;
4870 HOST_WIDE_INT fieldpos;
4872 unsigned int align2;
4874 if (local->index != NULL_TREE)
4876 /* Perform the index calculation in modulo arithmetic but
4877 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
4878 but we are using an unsigned sizetype. */
4879 unsigned prec = TYPE_PRECISION (sizetype);
4880 offset_int idx = wi::sext (wi::to_offset (local->index)
4881 - wi::to_offset (local->min_index), prec);
4882 fieldpos = (idx * wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (local->val))))
4883 .to_short_addr ();
4885 else if (local->field != NULL_TREE)
4886 fieldpos = int_byte_position (local->field);
4887 else
4888 fieldpos = 0;
4890 /* Output any buffered-up bit-fields preceding this element. */
4891 if (local->byte_buffer_in_use)
4893 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4894 local->total_bytes++;
4895 local->byte_buffer_in_use = false;
4898 /* Advance to offset of this element.
4899 Note no alignment needed in an array, since that is guaranteed
4900 if each element has the proper size. */
4901 if ((local->field != NULL_TREE || local->index != NULL_TREE)
4902 && fieldpos > local->total_bytes)
4904 assemble_zeros (fieldpos - local->total_bytes);
4905 local->total_bytes = fieldpos;
4908 /* Find the alignment of this element. */
4909 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
4911 /* Determine size this element should occupy. */
4912 if (local->field)
4914 fieldsize = 0;
4916 /* If this is an array with an unspecified upper bound,
4917 the initializer determines the size. */
4918 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
4919 but we cannot do this until the deprecated support for
4920 initializing zero-length array members is removed. */
4921 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
4922 && TYPE_DOMAIN (TREE_TYPE (local->field))
4923 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field))))
4925 fieldsize = array_size_for_constructor (local->val);
4926 /* Given a non-empty initialization, this field had
4927 better be last. */
4928 gcc_assert (!fieldsize || !DECL_CHAIN (local->field));
4930 else
4931 fieldsize = tree_to_uhwi (DECL_SIZE_UNIT (local->field));
4933 else
4934 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
4936 /* Output the element's initial value. */
4937 if (local->val == NULL_TREE)
4938 assemble_zeros (fieldsize);
4939 else
4940 fieldsize
4941 = output_constant (local->val, fieldsize, align2, local->reverse);
4943 /* Count its size. */
4944 local->total_bytes += fieldsize;
4947 /* Helper for output_constructor. From the LOCAL state, output an element
4948 that is a true bitfield or part of an outer one. BIT_OFFSET is the offset
4949 from the start of a possibly ongoing outer byte buffer. */
4951 static void
4952 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
4954 /* Bit size of this element. */
4955 HOST_WIDE_INT ebitsize
4956 = (local->field
4957 ? tree_to_uhwi (DECL_SIZE (local->field))
4958 : tree_to_uhwi (TYPE_SIZE (TREE_TYPE (local->type))));
4960 /* Relative index of this element if this is an array component. */
4961 HOST_WIDE_INT relative_index
4962 = (!local->field
4963 ? (local->index
4964 ? (tree_to_shwi (local->index)
4965 - tree_to_shwi (local->min_index))
4966 : local->last_relative_index + 1)
4967 : 0);
4969 /* Bit position of this element from the start of the containing
4970 constructor. */
4971 HOST_WIDE_INT constructor_relative_ebitpos
4972 = (local->field
4973 ? int_bit_position (local->field)
4974 : ebitsize * relative_index);
4976 /* Bit position of this element from the start of a possibly ongoing
4977 outer byte buffer. */
4978 HOST_WIDE_INT byte_relative_ebitpos
4979 = bit_offset + constructor_relative_ebitpos;
4981 /* From the start of a possibly ongoing outer byte buffer, offsets to
4982 the first bit of this element and to the first bit past the end of
4983 this element. */
4984 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
4985 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
4987 local->last_relative_index = relative_index;
4989 if (local->val == NULL_TREE)
4990 local->val = integer_zero_node;
4992 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
4993 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
4994 local->val = TREE_OPERAND (local->val, 0);
4996 if (TREE_CODE (local->val) != INTEGER_CST
4997 && TREE_CODE (local->val) != CONSTRUCTOR)
4999 error ("invalid initial value for member %qE", DECL_NAME (local->field));
5000 return;
5003 /* If this field does not start in this (or next) byte, skip some bytes. */
5004 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5006 /* Output remnant of any bit field in previous bytes. */
5007 if (local->byte_buffer_in_use)
5009 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5010 local->total_bytes++;
5011 local->byte_buffer_in_use = false;
5014 /* If still not at proper byte, advance to there. */
5015 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5017 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
5018 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
5019 local->total_bytes = next_offset / BITS_PER_UNIT;
5023 /* Set up the buffer if necessary. */
5024 if (!local->byte_buffer_in_use)
5026 local->byte = 0;
5027 if (ebitsize > 0)
5028 local->byte_buffer_in_use = true;
5031 /* If this is nested constructor, recurse passing the bit offset and the
5032 pending data, then retrieve the new pending data afterwards. */
5033 if (TREE_CODE (local->val) == CONSTRUCTOR)
5035 oc_outer_state temp_state;
5036 temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5037 temp_state.byte = local->byte;
5038 local->total_bytes
5039 += output_constructor (local->val, 0, 0, local->reverse, &temp_state);
5040 local->byte = temp_state.byte;
5041 return;
5044 /* Otherwise, we must split the element into pieces that fall within
5045 separate bytes, and combine each byte with previous or following
5046 bit-fields. */
5047 while (next_offset < end_offset)
5049 int this_time;
5050 int shift;
5051 HOST_WIDE_INT value;
5052 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5053 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5055 /* Advance from byte to byte within this element when necessary. */
5056 while (next_byte != local->total_bytes)
5058 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5059 local->total_bytes++;
5060 local->byte = 0;
5063 /* Number of bits we can process at once (all part of the same byte). */
5064 this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5065 if (local->reverse ? !BYTES_BIG_ENDIAN : BYTES_BIG_ENDIAN)
5067 /* On big-endian machine, take the most significant bits (of the
5068 bits that are significant) first and put them into bytes from
5069 the most significant end. */
5070 shift = end_offset - next_offset - this_time;
5072 /* Don't try to take a bunch of bits that cross
5073 the word boundary in the INTEGER_CST. We can
5074 only select bits from one element. */
5075 if ((shift / HOST_BITS_PER_WIDE_INT)
5076 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5078 const int end = shift + this_time - 1;
5079 shift = end & -HOST_BITS_PER_WIDE_INT;
5080 this_time = end - shift + 1;
5083 /* Now get the bits from the appropriate constant word. */
5084 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5085 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5087 /* Get the result. This works only when:
5088 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5089 local->byte |= (((value >> shift)
5090 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5091 << (BITS_PER_UNIT - this_time - next_bit));
5093 else
5095 /* On little-endian machines, take the least significant bits of
5096 the value first and pack them starting at the least significant
5097 bits of the bytes. */
5098 shift = next_offset - byte_relative_ebitpos;
5100 /* Don't try to take a bunch of bits that cross
5101 the word boundary in the INTEGER_CST. We can
5102 only select bits from one element. */
5103 if ((shift / HOST_BITS_PER_WIDE_INT)
5104 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5105 this_time
5106 = HOST_BITS_PER_WIDE_INT - (shift & (HOST_BITS_PER_WIDE_INT - 1));
5108 /* Now get the bits from the appropriate constant word. */
5109 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5110 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5112 /* Get the result. This works only when:
5113 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5114 local->byte |= (((value >> shift)
5115 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5116 << next_bit);
5119 next_offset += this_time;
5120 local->byte_buffer_in_use = true;
5124 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5125 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5126 caller output state of relevance in recursive invocations. */
5128 static unsigned HOST_WIDE_INT
5129 output_constructor (tree exp, unsigned HOST_WIDE_INT size, unsigned int align,
5130 bool reverse, oc_outer_state *outer)
5132 unsigned HOST_WIDE_INT cnt;
5133 constructor_elt *ce;
5134 oc_local_state local;
5136 /* Setup our local state to communicate with helpers. */
5137 local.exp = exp;
5138 local.type = TREE_TYPE (exp);
5139 local.size = size;
5140 local.align = align;
5141 if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5142 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5143 else
5144 local.min_index = NULL_TREE;
5146 local.total_bytes = 0;
5147 local.byte_buffer_in_use = outer != NULL;
5148 local.byte = outer ? outer->byte : 0;
5149 local.last_relative_index = -1;
5150 /* The storage order is specified for every aggregate type. */
5151 if (AGGREGATE_TYPE_P (local.type))
5152 local.reverse = TYPE_REVERSE_STORAGE_ORDER (local.type);
5153 else
5154 local.reverse = reverse;
5156 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5158 /* As CE goes through the elements of the constant, FIELD goes through the
5159 structure fields if the constant is a structure. If the constant is a
5160 union, we override this by getting the field from the TREE_LIST element.
5161 But the constant could also be an array. Then FIELD is zero.
5163 There is always a maximum of one element in the chain LINK for unions
5164 (even if the initializer in a source program incorrectly contains
5165 more one). */
5167 if (TREE_CODE (local.type) == RECORD_TYPE)
5168 local.field = TYPE_FIELDS (local.type);
5169 else
5170 local.field = NULL_TREE;
5172 for (cnt = 0;
5173 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5174 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5176 local.val = ce->value;
5177 local.index = NULL_TREE;
5179 /* The element in a union constructor specifies the proper field
5180 or index. */
5181 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5182 local.field = ce->index;
5184 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5185 local.index = ce->index;
5187 if (local.field && flag_verbose_asm)
5188 fprintf (asm_out_file, "%s %s:\n",
5189 ASM_COMMENT_START,
5190 DECL_NAME (local.field)
5191 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5192 : "<anonymous>");
5194 /* Eliminate the marker that makes a cast not be an lvalue. */
5195 if (local.val != NULL_TREE)
5196 STRIP_NOPS (local.val);
5198 /* Output the current element, using the appropriate helper ... */
5200 /* For an array slice not part of an outer bitfield. */
5201 if (!outer
5202 && local.index != NULL_TREE
5203 && TREE_CODE (local.index) == RANGE_EXPR)
5204 output_constructor_array_range (&local);
5206 /* For a field that is neither a true bitfield nor part of an outer one,
5207 known to be at least byte aligned and multiple-of-bytes long. */
5208 else if (!outer
5209 && (local.field == NULL_TREE
5210 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5211 output_constructor_regular_field (&local);
5213 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5214 supported for scalar fields, so we may need to convert first. */
5215 else
5217 if (TREE_CODE (local.val) == REAL_CST)
5218 local.val
5219 = fold_unary (VIEW_CONVERT_EXPR,
5220 build_nonstandard_integer_type
5221 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5222 local.val);
5223 output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5227 /* If we are not at toplevel, save the pending data for our caller.
5228 Otherwise output the pending data and padding zeros as needed. */
5229 if (outer)
5230 outer->byte = local.byte;
5231 else
5233 if (local.byte_buffer_in_use)
5235 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5236 local.total_bytes++;
5239 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5241 assemble_zeros (local.size - local.total_bytes);
5242 local.total_bytes = local.size;
5246 return local.total_bytes;
5249 /* Mark DECL as weak. */
5251 static void
5252 mark_weak (tree decl)
5254 if (DECL_WEAK (decl))
5255 return;
5257 struct symtab_node *n = symtab_node::get (decl);
5258 if (n && n->refuse_visibility_changes)
5259 error ("%+D declared weak after being used", decl);
5260 DECL_WEAK (decl) = 1;
5262 if (DECL_RTL_SET_P (decl)
5263 && MEM_P (DECL_RTL (decl))
5264 && XEXP (DECL_RTL (decl), 0)
5265 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5266 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5269 /* Merge weak status between NEWDECL and OLDDECL. */
5271 void
5272 merge_weak (tree newdecl, tree olddecl)
5274 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5276 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5278 tree *pwd;
5279 /* We put the NEWDECL on the weak_decls list at some point
5280 and OLDDECL as well. Keep just OLDDECL on the list. */
5281 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5282 if (TREE_VALUE (*pwd) == newdecl)
5284 *pwd = TREE_CHAIN (*pwd);
5285 break;
5288 return;
5291 if (DECL_WEAK (newdecl))
5293 tree wd;
5295 /* NEWDECL is weak, but OLDDECL is not. */
5297 /* If we already output the OLDDECL, we're in trouble; we can't
5298 go back and make it weak. This should never happen in
5299 unit-at-a-time compilation. */
5300 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5302 /* If we've already generated rtl referencing OLDDECL, we may
5303 have done so in a way that will not function properly with
5304 a weak symbol. Again in unit-at-a-time this should be
5305 impossible. */
5306 gcc_assert (!TREE_USED (olddecl)
5307 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5309 if (TARGET_SUPPORTS_WEAK)
5311 /* We put the NEWDECL on the weak_decls list at some point.
5312 Replace it with the OLDDECL. */
5313 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5314 if (TREE_VALUE (wd) == newdecl)
5316 TREE_VALUE (wd) = olddecl;
5317 break;
5319 /* We may not find the entry on the list. If NEWDECL is a
5320 weak alias, then we will have already called
5321 globalize_decl to remove the entry; in that case, we do
5322 not need to do anything. */
5325 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5326 mark_weak (olddecl);
5328 else
5329 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5330 weak. Just update NEWDECL to indicate that it's weak too. */
5331 mark_weak (newdecl);
5334 /* Declare DECL to be a weak symbol. */
5336 void
5337 declare_weak (tree decl)
5339 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5340 if (! TREE_PUBLIC (decl))
5341 error ("weak declaration of %q+D must be public", decl);
5342 else if (!TARGET_SUPPORTS_WEAK)
5343 warning (0, "weak declaration of %q+D not supported", decl);
5345 mark_weak (decl);
5346 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5347 DECL_ATTRIBUTES (decl)
5348 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5351 static void
5352 weak_finish_1 (tree decl)
5354 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5355 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5356 #endif
5358 if (! TREE_USED (decl))
5359 return;
5361 #ifdef ASM_WEAKEN_DECL
5362 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5363 #else
5364 #ifdef ASM_WEAKEN_LABEL
5365 ASM_WEAKEN_LABEL (asm_out_file, name);
5366 #else
5367 #ifdef ASM_OUTPUT_WEAK_ALIAS
5369 static bool warn_once = 0;
5370 if (! warn_once)
5372 warning (0, "only weak aliases are supported in this configuration");
5373 warn_once = 1;
5375 return;
5377 #endif
5378 #endif
5379 #endif
5382 /* Fiven an assembly name, find the decl it is associated with. */
5383 static tree
5384 find_decl (tree target)
5386 symtab_node *node = symtab_node::get_for_asmname (target);
5387 if (node)
5388 return node->decl;
5389 return NULL_TREE;
5392 /* This TREE_LIST contains weakref targets. */
5394 static GTY(()) tree weakref_targets;
5396 /* Emit any pending weak declarations. */
5398 void
5399 weak_finish (void)
5401 tree t;
5403 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5405 tree alias_decl = TREE_PURPOSE (t);
5406 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5408 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5409 /* Remove alias_decl from the weak list, but leave entries for
5410 the target alone. */
5411 target = NULL_TREE;
5412 #ifndef ASM_OUTPUT_WEAKREF
5413 else if (! TREE_SYMBOL_REFERENCED (target))
5415 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5416 defined, otherwise we and weak_finish_1 would use
5417 different macros. */
5418 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5419 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5420 # else
5421 tree decl = find_decl (target);
5423 if (! decl)
5425 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5426 TREE_CODE (alias_decl), target,
5427 TREE_TYPE (alias_decl));
5429 DECL_EXTERNAL (decl) = 1;
5430 TREE_PUBLIC (decl) = 1;
5431 DECL_ARTIFICIAL (decl) = 1;
5432 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5433 TREE_USED (decl) = 1;
5436 weak_finish_1 (decl);
5437 # endif
5439 #endif
5442 tree *p;
5443 tree t2;
5445 /* Remove the alias and the target from the pending weak list
5446 so that we do not emit any .weak directives for the former,
5447 nor multiple .weak directives for the latter. */
5448 for (p = &weak_decls; (t2 = *p) ; )
5450 if (TREE_VALUE (t2) == alias_decl
5451 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5452 *p = TREE_CHAIN (t2);
5453 else
5454 p = &TREE_CHAIN (t2);
5457 /* Remove other weakrefs to the same target, to speed things up. */
5458 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5460 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5461 *p = TREE_CHAIN (t2);
5462 else
5463 p = &TREE_CHAIN (t2);
5468 for (t = weak_decls; t; t = TREE_CHAIN (t))
5470 tree decl = TREE_VALUE (t);
5472 weak_finish_1 (decl);
5476 /* Emit the assembly bits to indicate that DECL is globally visible. */
5478 static void
5479 globalize_decl (tree decl)
5482 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5483 if (DECL_WEAK (decl))
5485 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5486 tree *p, t;
5488 #ifdef ASM_WEAKEN_DECL
5489 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5490 #else
5491 ASM_WEAKEN_LABEL (asm_out_file, name);
5492 #endif
5494 /* Remove this function from the pending weak list so that
5495 we do not emit multiple .weak directives for it. */
5496 for (p = &weak_decls; (t = *p) ; )
5498 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5499 *p = TREE_CHAIN (t);
5500 else
5501 p = &TREE_CHAIN (t);
5504 /* Remove weakrefs to the same target from the pending weakref
5505 list, for the same reason. */
5506 for (p = &weakref_targets; (t = *p) ; )
5508 if (DECL_ASSEMBLER_NAME (decl)
5509 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5510 *p = TREE_CHAIN (t);
5511 else
5512 p = &TREE_CHAIN (t);
5515 return;
5517 #endif
5519 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5522 vec<alias_pair, va_gc> *alias_pairs;
5524 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5525 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5526 tree node is DECL to have the value of the tree node TARGET. */
5528 void
5529 do_assemble_alias (tree decl, tree target)
5531 /* Emulated TLS had better not get this var. */
5532 gcc_assert (!(!targetm.have_tls
5533 && TREE_CODE (decl) == VAR_DECL
5534 && DECL_THREAD_LOCAL_P (decl)));
5536 if (TREE_ASM_WRITTEN (decl))
5537 return;
5539 /* We must force creation of DECL_RTL for debug info generation, even though
5540 we don't use it here. */
5541 make_decl_rtl (decl);
5543 TREE_ASM_WRITTEN (decl) = 1;
5544 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5546 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5548 ultimate_transparent_alias_target (&target);
5550 if (!TREE_SYMBOL_REFERENCED (target))
5551 weakref_targets = tree_cons (decl, target, weakref_targets);
5553 #ifdef ASM_OUTPUT_WEAKREF
5554 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5555 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5556 IDENTIFIER_POINTER (target));
5557 #else
5558 if (!TARGET_SUPPORTS_WEAK)
5560 error_at (DECL_SOURCE_LOCATION (decl),
5561 "weakref is not supported in this configuration");
5562 return;
5564 #endif
5565 return;
5568 #ifdef ASM_OUTPUT_DEF
5569 /* Make name accessible from other files, if appropriate. */
5571 if (TREE_PUBLIC (decl))
5573 globalize_decl (decl);
5574 maybe_assemble_visibility (decl);
5576 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5578 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5579 if (targetm.has_ifunc_p ())
5580 ASM_OUTPUT_TYPE_DIRECTIVE
5581 (asm_out_file, IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5582 IFUNC_ASM_TYPE);
5583 else
5584 #endif
5585 error_at (DECL_SOURCE_LOCATION (decl),
5586 "ifunc is not supported on this target");
5589 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5590 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5591 # else
5592 ASM_OUTPUT_DEF (asm_out_file,
5593 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5594 IDENTIFIER_POINTER (target));
5595 # endif
5596 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5598 const char *name;
5599 tree *p, t;
5601 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5602 # ifdef ASM_WEAKEN_DECL
5603 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5604 # else
5605 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5606 # endif
5607 /* Remove this function from the pending weak list so that
5608 we do not emit multiple .weak directives for it. */
5609 for (p = &weak_decls; (t = *p) ; )
5610 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5611 *p = TREE_CHAIN (t);
5612 else
5613 p = &TREE_CHAIN (t);
5615 /* Remove weakrefs to the same target from the pending weakref
5616 list, for the same reason. */
5617 for (p = &weakref_targets; (t = *p) ; )
5619 if (DECL_ASSEMBLER_NAME (decl)
5620 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5621 *p = TREE_CHAIN (t);
5622 else
5623 p = &TREE_CHAIN (t);
5626 #endif
5629 /* Emit an assembler directive to make the symbol for DECL an alias to
5630 the symbol for TARGET. */
5632 void
5633 assemble_alias (tree decl, tree target)
5635 tree target_decl;
5637 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5639 tree alias = DECL_ASSEMBLER_NAME (decl);
5641 ultimate_transparent_alias_target (&target);
5643 if (alias == target)
5644 error ("weakref %q+D ultimately targets itself", decl);
5645 if (TREE_PUBLIC (decl))
5646 error ("weakref %q+D must have static linkage", decl);
5648 else
5650 #if !defined (ASM_OUTPUT_DEF)
5651 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5652 error_at (DECL_SOURCE_LOCATION (decl),
5653 "alias definitions not supported in this configuration");
5654 TREE_ASM_WRITTEN (decl) = 1;
5655 return;
5656 # else
5657 if (!DECL_WEAK (decl))
5659 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5660 error_at (DECL_SOURCE_LOCATION (decl),
5661 "ifunc is not supported in this configuration");
5662 else
5663 error_at (DECL_SOURCE_LOCATION (decl),
5664 "only weak aliases are supported in this configuration");
5665 TREE_ASM_WRITTEN (decl) = 1;
5666 return;
5668 # endif
5669 #endif
5671 TREE_USED (decl) = 1;
5673 /* Allow aliases to aliases. */
5674 if (TREE_CODE (decl) == FUNCTION_DECL)
5675 cgraph_node::get_create (decl)->alias = true;
5676 else
5677 varpool_node::get_create (decl)->alias = true;
5679 /* If the target has already been emitted, we don't have to queue the
5680 alias. This saves a tad of memory. */
5681 if (symtab->global_info_ready)
5682 target_decl = find_decl (target);
5683 else
5684 target_decl= NULL;
5685 if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5686 || symtab->state >= EXPANSION)
5687 do_assemble_alias (decl, target);
5688 else
5690 alias_pair p = {decl, target};
5691 vec_safe_push (alias_pairs, p);
5695 /* Record and output a table of translations from original function
5696 to its transaction aware clone. Note that tm_pure functions are
5697 considered to be their own clone. */
5699 static GTY((if_marked ("tree_map_marked_p"), param_is (struct tree_map)))
5700 htab_t tm_clone_hash;
5702 void
5703 record_tm_clone_pair (tree o, tree n)
5705 struct tree_map **slot, *h;
5707 if (tm_clone_hash == NULL)
5708 tm_clone_hash = htab_create_ggc (32, tree_map_hash, tree_map_eq, 0);
5710 h = ggc_alloc<tree_map> ();
5711 h->hash = htab_hash_pointer (o);
5712 h->base.from = o;
5713 h->to = n;
5715 slot = (struct tree_map **)
5716 htab_find_slot_with_hash (tm_clone_hash, h, h->hash, INSERT);
5717 *slot = h;
5720 tree
5721 get_tm_clone_pair (tree o)
5723 if (tm_clone_hash)
5725 struct tree_map *h, in;
5727 in.base.from = o;
5728 in.hash = htab_hash_pointer (o);
5729 h = (struct tree_map *) htab_find_with_hash (tm_clone_hash,
5730 &in, in.hash);
5731 if (h)
5732 return h->to;
5734 return NULL_TREE;
5737 typedef struct tm_alias_pair
5739 unsigned int uid;
5740 tree from;
5741 tree to;
5742 } tm_alias_pair;
5745 /* Helper function for finish_tm_clone_pairs. Dump a hash table entry
5746 into a VEC in INFO. */
5748 static int
5749 dump_tm_clone_to_vec (void **slot, void *info)
5751 struct tree_map *map = (struct tree_map *) *slot;
5752 vec<tm_alias_pair> *tm_alias_pairs = (vec<tm_alias_pair> *) info;
5753 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
5754 tm_alias_pairs->safe_push (p);
5755 return 1;
5758 /* Dump the actual pairs to the .tm_clone_table section. */
5760 static void
5761 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
5763 unsigned i;
5764 tm_alias_pair *p;
5765 bool switched = false;
5767 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
5769 tree src = p->from;
5770 tree dst = p->to;
5771 struct cgraph_node *src_n = cgraph_node::get (src);
5772 struct cgraph_node *dst_n = cgraph_node::get (dst);
5774 /* The function ipa_tm_create_version() marks the clone as needed if
5775 the original function was needed. But we also mark the clone as
5776 needed if we ever called the clone indirectly through
5777 TM_GETTMCLONE. If neither of these are true, we didn't generate
5778 a clone, and we didn't call it indirectly... no sense keeping it
5779 in the clone table. */
5780 if (!dst_n || !dst_n->definition)
5781 continue;
5783 /* This covers the case where we have optimized the original
5784 function away, and only access the transactional clone. */
5785 if (!src_n || !src_n->definition)
5786 continue;
5788 if (!switched)
5790 switch_to_section (targetm.asm_out.tm_clone_table_section ());
5791 assemble_align (POINTER_SIZE);
5792 switched = true;
5795 assemble_integer (XEXP (DECL_RTL (src), 0),
5796 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
5797 assemble_integer (XEXP (DECL_RTL (dst), 0),
5798 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
5802 /* Provide a default for the tm_clone_table section. */
5804 section *
5805 default_clone_table_section (void)
5807 return get_named_section (NULL, ".tm_clone_table", 3);
5810 /* Helper comparison function for qsorting by the DECL_UID stored in
5811 alias_pair->emitted_diags. */
5813 static int
5814 tm_alias_pair_cmp (const void *x, const void *y)
5816 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
5817 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
5818 if (p1->uid < p2->uid)
5819 return -1;
5820 if (p1->uid > p2->uid)
5821 return 1;
5822 return 0;
5825 void
5826 finish_tm_clone_pairs (void)
5828 vec<tm_alias_pair> tm_alias_pairs = vNULL;
5830 if (tm_clone_hash == NULL)
5831 return;
5833 /* We need a determenistic order for the .tm_clone_table, otherwise
5834 we will get bootstrap comparison failures, so dump the hash table
5835 to a vector, sort it, and dump the vector. */
5837 /* Dump the hashtable to a vector. */
5838 htab_traverse_noresize (tm_clone_hash, dump_tm_clone_to_vec,
5839 (void *) &tm_alias_pairs);
5840 /* Sort it. */
5841 tm_alias_pairs.qsort (tm_alias_pair_cmp);
5843 /* Dump it. */
5844 dump_tm_clone_pairs (tm_alias_pairs);
5846 htab_delete (tm_clone_hash);
5847 tm_clone_hash = NULL;
5848 tm_alias_pairs.release ();
5852 /* Emit an assembler directive to set symbol for DECL visibility to
5853 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
5855 void
5856 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
5857 int vis ATTRIBUTE_UNUSED)
5859 #ifdef HAVE_GAS_HIDDEN
5860 static const char * const visibility_types[] = {
5861 NULL, "protected", "hidden", "internal"
5864 const char *name, *type;
5866 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5867 type = visibility_types[vis];
5869 fprintf (asm_out_file, "\t.%s\t", type);
5870 assemble_name (asm_out_file, name);
5871 fprintf (asm_out_file, "\n");
5872 #else
5873 if (!DECL_ARTIFICIAL (decl))
5874 warning (OPT_Wattributes, "visibility attribute not supported "
5875 "in this configuration; ignored");
5876 #endif
5879 /* A helper function to call assemble_visibility when needed for a decl. */
5882 maybe_assemble_visibility (tree decl)
5884 enum symbol_visibility vis = DECL_VISIBILITY (decl);
5886 if (vis != VISIBILITY_DEFAULT)
5888 targetm.asm_out.assemble_visibility (decl, vis);
5889 return 1;
5891 else
5892 return 0;
5895 /* Returns 1 if the target configuration supports defining public symbols
5896 so that one of them will be chosen at link time instead of generating a
5897 multiply-defined symbol error, whether through the use of weak symbols or
5898 a target-specific mechanism for having duplicates discarded. */
5901 supports_one_only (void)
5903 if (SUPPORTS_ONE_ONLY)
5904 return 1;
5905 return TARGET_SUPPORTS_WEAK;
5908 /* Set up DECL as a public symbol that can be defined in multiple
5909 translation units without generating a linker error. */
5911 void
5912 make_decl_one_only (tree decl, tree comdat_group)
5914 struct symtab_node *symbol;
5915 gcc_assert (TREE_CODE (decl) == VAR_DECL
5916 || TREE_CODE (decl) == FUNCTION_DECL);
5918 TREE_PUBLIC (decl) = 1;
5920 if (TREE_CODE (decl) == VAR_DECL)
5921 symbol = varpool_node::get_create (decl);
5922 else
5923 symbol = cgraph_node::get_create (decl);
5925 if (SUPPORTS_ONE_ONLY)
5927 #ifdef MAKE_DECL_ONE_ONLY
5928 MAKE_DECL_ONE_ONLY (decl);
5929 #endif
5930 symbol->set_comdat_group (comdat_group);
5932 else if (TREE_CODE (decl) == VAR_DECL
5933 && (DECL_INITIAL (decl) == 0
5934 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
5935 DECL_COMMON (decl) = 1;
5936 else
5938 gcc_assert (TARGET_SUPPORTS_WEAK);
5939 DECL_WEAK (decl) = 1;
5943 void
5944 init_varasm_once (void)
5946 section_htab = htab_create_ggc (31, section_entry_hash,
5947 section_entry_eq, NULL);
5948 object_block_htab = htab_create_ggc (31, object_block_entry_hash,
5949 object_block_entry_eq, NULL);
5950 const_desc_htab = htab_create_ggc (1009, const_desc_hash,
5951 const_desc_eq, NULL);
5953 const_alias_set = new_alias_set ();
5954 shared_constant_pool = create_constant_pool ();
5956 #ifdef TEXT_SECTION_ASM_OP
5957 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
5958 TEXT_SECTION_ASM_OP);
5959 #endif
5961 #ifdef DATA_SECTION_ASM_OP
5962 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5963 DATA_SECTION_ASM_OP);
5964 #endif
5966 #ifdef SDATA_SECTION_ASM_OP
5967 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5968 SDATA_SECTION_ASM_OP);
5969 #endif
5971 #ifdef READONLY_DATA_SECTION_ASM_OP
5972 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
5973 READONLY_DATA_SECTION_ASM_OP);
5974 #endif
5976 #ifdef CTORS_SECTION_ASM_OP
5977 ctors_section = get_unnamed_section (0, output_section_asm_op,
5978 CTORS_SECTION_ASM_OP);
5979 #endif
5981 #ifdef DTORS_SECTION_ASM_OP
5982 dtors_section = get_unnamed_section (0, output_section_asm_op,
5983 DTORS_SECTION_ASM_OP);
5984 #endif
5986 #ifdef BSS_SECTION_ASM_OP
5987 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5988 output_section_asm_op,
5989 BSS_SECTION_ASM_OP);
5990 #endif
5992 #ifdef SBSS_SECTION_ASM_OP
5993 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5994 output_section_asm_op,
5995 SBSS_SECTION_ASM_OP);
5996 #endif
5998 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5999 | SECTION_COMMON, emit_tls_common);
6000 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6001 | SECTION_COMMON, emit_local);
6002 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6003 | SECTION_COMMON, emit_common);
6005 #if defined ASM_OUTPUT_ALIGNED_BSS
6006 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
6007 emit_bss);
6008 #endif
6010 targetm.asm_out.init_sections ();
6012 if (readonly_data_section == NULL)
6013 readonly_data_section = text_section;
6015 #ifdef ASM_OUTPUT_EXTERNAL
6016 pending_assemble_externals_set = new hash_set<tree>;
6017 #endif
6020 enum tls_model
6021 decl_default_tls_model (const_tree decl)
6023 enum tls_model kind;
6024 bool is_local;
6026 is_local = targetm.binds_local_p (decl);
6027 if (!flag_shlib)
6029 if (is_local)
6030 kind = TLS_MODEL_LOCAL_EXEC;
6031 else
6032 kind = TLS_MODEL_INITIAL_EXEC;
6035 /* Local dynamic is inefficient when we're not combining the
6036 parts of the address. */
6037 else if (optimize && is_local)
6038 kind = TLS_MODEL_LOCAL_DYNAMIC;
6039 else
6040 kind = TLS_MODEL_GLOBAL_DYNAMIC;
6041 if (kind < flag_tls_default)
6042 kind = flag_tls_default;
6044 return kind;
6047 /* Select a set of attributes for section NAME based on the properties
6048 of DECL and whether or not RELOC indicates that DECL's initializer
6049 might contain runtime relocations.
6051 We make the section read-only and executable for a function decl,
6052 read-only for a const data decl, and writable for a non-const data decl. */
6054 unsigned int
6055 default_section_type_flags (tree decl, const char *name, int reloc)
6057 unsigned int flags;
6059 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6060 flags = SECTION_CODE;
6061 else if (decl)
6063 enum section_category category
6064 = categorize_decl_for_section (decl, reloc);
6065 if (decl_readonly_section_1 (category))
6066 flags = 0;
6067 else if (category == SECCAT_DATA_REL_RO
6068 || category == SECCAT_DATA_REL_RO_LOCAL)
6069 flags = SECTION_WRITE | SECTION_RELRO;
6070 else
6071 flags = SECTION_WRITE;
6073 else
6075 flags = SECTION_WRITE;
6076 if (strcmp (name, ".data.rel.ro") == 0
6077 || strcmp (name, ".data.rel.ro.local") == 0)
6078 flags |= SECTION_RELRO;
6081 if (decl && DECL_P (decl) && DECL_COMDAT_GROUP (decl))
6082 flags |= SECTION_LINKONCE;
6084 if (strcmp (name, ".vtable_map_vars") == 0)
6085 flags |= SECTION_LINKONCE;
6087 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6088 flags |= SECTION_TLS | SECTION_WRITE;
6090 if (strcmp (name, ".bss") == 0
6091 || strncmp (name, ".bss.", 5) == 0
6092 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6093 || strcmp (name, ".persistent.bss") == 0
6094 || strcmp (name, ".sbss") == 0
6095 || strncmp (name, ".sbss.", 6) == 0
6096 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6097 flags |= SECTION_BSS;
6099 if (strcmp (name, ".tdata") == 0
6100 || strncmp (name, ".tdata.", 7) == 0
6101 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6102 flags |= SECTION_TLS;
6104 if (strcmp (name, ".tbss") == 0
6105 || strncmp (name, ".tbss.", 6) == 0
6106 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6107 flags |= SECTION_TLS | SECTION_BSS;
6109 /* These three sections have special ELF types. They are neither
6110 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
6111 want to print a section type (@progbits or @nobits). If someone
6112 is silly enough to emit code or TLS variables to one of these
6113 sections, then don't handle them specially. */
6114 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6115 && (strcmp (name, ".init_array") == 0
6116 || strcmp (name, ".fini_array") == 0
6117 || strcmp (name, ".preinit_array") == 0))
6118 flags |= SECTION_NOTYPE;
6120 return flags;
6123 /* Return true if the target supports some form of global BSS,
6124 either through bss_noswitch_section, or by selecting a BSS
6125 section in TARGET_ASM_SELECT_SECTION. */
6127 bool
6128 have_global_bss_p (void)
6130 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6133 /* Output assembly to switch to section NAME with attribute FLAGS.
6134 Four variants for common object file formats. */
6136 void
6137 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6138 unsigned int flags ATTRIBUTE_UNUSED,
6139 tree decl ATTRIBUTE_UNUSED)
6141 /* Some object formats don't support named sections at all. The
6142 front-end should already have flagged this as an error. */
6143 gcc_unreachable ();
6146 #ifndef TLS_SECTION_ASM_FLAG
6147 #define TLS_SECTION_ASM_FLAG 'T'
6148 #endif
6150 void
6151 default_elf_asm_named_section (const char *name, unsigned int flags,
6152 tree decl ATTRIBUTE_UNUSED)
6154 char flagchars[10], *f = flagchars;
6156 /* If we have already declared this section, we can use an
6157 abbreviated form to switch back to it -- unless this section is
6158 part of a COMDAT groups, in which case GAS requires the full
6159 declaration every time. */
6160 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6161 && (flags & SECTION_DECLARED))
6163 fprintf (asm_out_file, "\t.section\t%s\n", name);
6164 return;
6167 if (!(flags & SECTION_DEBUG))
6168 *f++ = 'a';
6169 if (flags & SECTION_EXCLUDE)
6170 *f++ = 'e';
6171 if (flags & SECTION_WRITE)
6172 *f++ = 'w';
6173 if (flags & SECTION_CODE)
6174 *f++ = 'x';
6175 if (flags & SECTION_SMALL)
6176 *f++ = 's';
6177 if (flags & SECTION_MERGE)
6178 *f++ = 'M';
6179 if (flags & SECTION_STRINGS)
6180 *f++ = 'S';
6181 if (flags & SECTION_TLS)
6182 *f++ = TLS_SECTION_ASM_FLAG;
6183 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6184 *f++ = 'G';
6185 *f = '\0';
6187 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6189 if (!(flags & SECTION_NOTYPE))
6191 const char *type;
6192 const char *format;
6194 if (flags & SECTION_BSS)
6195 type = "nobits";
6196 else
6197 type = "progbits";
6199 format = ",@%s";
6200 /* On platforms that use "@" as the assembly comment character,
6201 use "%" instead. */
6202 if (strcmp (ASM_COMMENT_START, "@") == 0)
6203 format = ",%%%s";
6204 fprintf (asm_out_file, format, type);
6206 if (flags & SECTION_ENTSIZE)
6207 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6208 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6210 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6211 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6212 else
6213 fprintf (asm_out_file, ",%s,comdat",
6214 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6218 putc ('\n', asm_out_file);
6221 void
6222 default_coff_asm_named_section (const char *name, unsigned int flags,
6223 tree decl ATTRIBUTE_UNUSED)
6225 char flagchars[8], *f = flagchars;
6227 if (flags & SECTION_WRITE)
6228 *f++ = 'w';
6229 if (flags & SECTION_CODE)
6230 *f++ = 'x';
6231 *f = '\0';
6233 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6236 void
6237 default_pe_asm_named_section (const char *name, unsigned int flags,
6238 tree decl)
6240 default_coff_asm_named_section (name, flags, decl);
6242 if (flags & SECTION_LINKONCE)
6244 /* Functions may have been compiled at various levels of
6245 optimization so we can't use `same_size' here.
6246 Instead, have the linker pick one. */
6247 fprintf (asm_out_file, "\t.linkonce %s\n",
6248 (flags & SECTION_CODE ? "discard" : "same_size"));
6252 /* The lame default section selector. */
6254 section *
6255 default_select_section (tree decl, int reloc,
6256 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6258 if (DECL_P (decl))
6260 if (decl_readonly_section (decl, reloc))
6261 return readonly_data_section;
6263 else if (TREE_CODE (decl) == CONSTRUCTOR)
6265 if (! ((flag_pic && reloc)
6266 || !TREE_READONLY (decl)
6267 || TREE_SIDE_EFFECTS (decl)
6268 || !TREE_CONSTANT (decl)))
6269 return readonly_data_section;
6271 else if (TREE_CODE (decl) == STRING_CST)
6272 return readonly_data_section;
6273 else if (! (flag_pic && reloc))
6274 return readonly_data_section;
6276 return data_section;
6279 enum section_category
6280 categorize_decl_for_section (const_tree decl, int reloc)
6282 enum section_category ret;
6284 if (TREE_CODE (decl) == FUNCTION_DECL)
6285 return SECCAT_TEXT;
6286 else if (TREE_CODE (decl) == STRING_CST)
6288 if ((flag_sanitize & SANITIZE_ADDRESS)
6289 && asan_protect_global (CONST_CAST_TREE (decl)))
6290 /* or !flag_merge_constants */
6291 return SECCAT_RODATA;
6292 else
6293 return SECCAT_RODATA_MERGE_STR;
6295 else if (TREE_CODE (decl) == VAR_DECL)
6297 if (bss_initializer_p (decl))
6298 ret = SECCAT_BSS;
6299 else if (! TREE_READONLY (decl)
6300 || TREE_SIDE_EFFECTS (decl)
6301 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
6303 /* Here the reloc_rw_mask is not testing whether the section should
6304 be read-only or not, but whether the dynamic link will have to
6305 do something. If so, we wish to segregate the data in order to
6306 minimize cache misses inside the dynamic linker. */
6307 if (reloc & targetm.asm_out.reloc_rw_mask ())
6308 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6309 else
6310 ret = SECCAT_DATA;
6312 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6313 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6314 else if (reloc || flag_merge_constants < 2
6315 || ((flag_sanitize & SANITIZE_ADDRESS)
6316 && asan_protect_global (CONST_CAST_TREE (decl))))
6317 /* C and C++ don't allow different variables to share the same
6318 location. -fmerge-all-constants allows even that (at the
6319 expense of not conforming). */
6320 ret = SECCAT_RODATA;
6321 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6322 ret = SECCAT_RODATA_MERGE_STR_INIT;
6323 else
6324 ret = SECCAT_RODATA_MERGE_CONST;
6326 else if (TREE_CODE (decl) == CONSTRUCTOR)
6328 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6329 || TREE_SIDE_EFFECTS (decl)
6330 || ! TREE_CONSTANT (decl))
6331 ret = SECCAT_DATA;
6332 else
6333 ret = SECCAT_RODATA;
6335 else
6336 ret = SECCAT_RODATA;
6338 /* There are no read-only thread-local sections. */
6339 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6341 /* Note that this would be *just* SECCAT_BSS, except that there's
6342 no concept of a read-only thread-local-data section. */
6343 if (ret == SECCAT_BSS
6344 || (flag_zero_initialized_in_bss
6345 && initializer_zerop (DECL_INITIAL (decl))))
6346 ret = SECCAT_TBSS;
6347 else
6348 ret = SECCAT_TDATA;
6351 /* If the target uses small data sections, select it. */
6352 else if (targetm.in_small_data_p (decl))
6354 if (ret == SECCAT_BSS)
6355 ret = SECCAT_SBSS;
6356 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6357 ret = SECCAT_SRODATA;
6358 else
6359 ret = SECCAT_SDATA;
6362 return ret;
6365 static bool
6366 decl_readonly_section_1 (enum section_category category)
6368 switch (category)
6370 case SECCAT_RODATA:
6371 case SECCAT_RODATA_MERGE_STR:
6372 case SECCAT_RODATA_MERGE_STR_INIT:
6373 case SECCAT_RODATA_MERGE_CONST:
6374 case SECCAT_SRODATA:
6375 return true;
6376 default:
6377 return false;
6381 bool
6382 decl_readonly_section (const_tree decl, int reloc)
6384 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6387 /* Select a section based on the above categorization. */
6389 section *
6390 default_elf_select_section (tree decl, int reloc,
6391 unsigned HOST_WIDE_INT align)
6393 const char *sname;
6394 switch (categorize_decl_for_section (decl, reloc))
6396 case SECCAT_TEXT:
6397 /* We're not supposed to be called on FUNCTION_DECLs. */
6398 gcc_unreachable ();
6399 case SECCAT_RODATA:
6400 return readonly_data_section;
6401 case SECCAT_RODATA_MERGE_STR:
6402 return mergeable_string_section (decl, align, 0);
6403 case SECCAT_RODATA_MERGE_STR_INIT:
6404 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6405 case SECCAT_RODATA_MERGE_CONST:
6406 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6407 case SECCAT_SRODATA:
6408 sname = ".sdata2";
6409 break;
6410 case SECCAT_DATA:
6411 return data_section;
6412 case SECCAT_DATA_REL:
6413 sname = ".data.rel";
6414 break;
6415 case SECCAT_DATA_REL_LOCAL:
6416 sname = ".data.rel.local";
6417 break;
6418 case SECCAT_DATA_REL_RO:
6419 sname = ".data.rel.ro";
6420 break;
6421 case SECCAT_DATA_REL_RO_LOCAL:
6422 sname = ".data.rel.ro.local";
6423 break;
6424 case SECCAT_SDATA:
6425 sname = ".sdata";
6426 break;
6427 case SECCAT_TDATA:
6428 sname = ".tdata";
6429 break;
6430 case SECCAT_BSS:
6431 if (bss_section)
6432 return bss_section;
6433 sname = ".bss";
6434 break;
6435 case SECCAT_SBSS:
6436 sname = ".sbss";
6437 break;
6438 case SECCAT_TBSS:
6439 sname = ".tbss";
6440 break;
6441 default:
6442 gcc_unreachable ();
6445 return get_named_section (decl, sname, reloc);
6448 /* Construct a unique section name based on the decl name and the
6449 categorization performed above. */
6451 void
6452 default_unique_section (tree decl, int reloc)
6454 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6455 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6456 const char *prefix, *name, *linkonce;
6457 char *string;
6459 switch (categorize_decl_for_section (decl, reloc))
6461 case SECCAT_TEXT:
6462 prefix = one_only ? ".t" : ".text";
6463 break;
6464 case SECCAT_RODATA:
6465 case SECCAT_RODATA_MERGE_STR:
6466 case SECCAT_RODATA_MERGE_STR_INIT:
6467 case SECCAT_RODATA_MERGE_CONST:
6468 prefix = one_only ? ".r" : ".rodata";
6469 break;
6470 case SECCAT_SRODATA:
6471 prefix = one_only ? ".s2" : ".sdata2";
6472 break;
6473 case SECCAT_DATA:
6474 prefix = one_only ? ".d" : ".data";
6475 break;
6476 case SECCAT_DATA_REL:
6477 prefix = one_only ? ".d.rel" : ".data.rel";
6478 break;
6479 case SECCAT_DATA_REL_LOCAL:
6480 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6481 break;
6482 case SECCAT_DATA_REL_RO:
6483 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6484 break;
6485 case SECCAT_DATA_REL_RO_LOCAL:
6486 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6487 break;
6488 case SECCAT_SDATA:
6489 prefix = one_only ? ".s" : ".sdata";
6490 break;
6491 case SECCAT_BSS:
6492 prefix = one_only ? ".b" : ".bss";
6493 break;
6494 case SECCAT_SBSS:
6495 prefix = one_only ? ".sb" : ".sbss";
6496 break;
6497 case SECCAT_TDATA:
6498 prefix = one_only ? ".td" : ".tdata";
6499 break;
6500 case SECCAT_TBSS:
6501 prefix = one_only ? ".tb" : ".tbss";
6502 break;
6503 default:
6504 gcc_unreachable ();
6507 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
6508 name = targetm.strip_name_encoding (name);
6510 /* If we're using one_only, then there needs to be a .gnu.linkonce
6511 prefix to the section name. */
6512 linkonce = one_only ? ".gnu.linkonce" : "";
6514 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6516 set_decl_section_name (decl, string);
6519 /* Subroutine of compute_reloc_for_rtx for leaf rtxes. */
6521 static int
6522 compute_reloc_for_rtx_1 (const_rtx x)
6524 switch (GET_CODE (x))
6526 case SYMBOL_REF:
6527 return SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6528 case LABEL_REF:
6529 return 1;
6530 default:
6531 return 0;
6535 /* Like compute_reloc_for_constant, except for an RTX. The return value
6536 is a mask for which bit 1 indicates a global relocation, and bit 0
6537 indicates a local relocation. */
6539 static int
6540 compute_reloc_for_rtx (const_rtx x)
6542 switch (GET_CODE (x))
6544 case SYMBOL_REF:
6545 case LABEL_REF:
6546 return compute_reloc_for_rtx_1 (x);
6548 case CONST:
6550 int reloc = 0;
6551 subrtx_iterator::array_type array;
6552 FOR_EACH_SUBRTX (iter, array, x, ALL)
6553 reloc |= compute_reloc_for_rtx_1 (*iter);
6554 return reloc;
6557 default:
6558 return 0;
6562 section *
6563 default_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
6564 rtx x,
6565 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6567 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6568 return data_section;
6569 else
6570 return readonly_data_section;
6573 section *
6574 default_elf_select_rtx_section (enum machine_mode mode, rtx x,
6575 unsigned HOST_WIDE_INT align)
6577 int reloc = compute_reloc_for_rtx (x);
6579 /* ??? Handle small data here somehow. */
6581 if (reloc & targetm.asm_out.reloc_rw_mask ())
6583 if (reloc == 1)
6584 return get_named_section (NULL, ".data.rel.ro.local", 1);
6585 else
6586 return get_named_section (NULL, ".data.rel.ro", 3);
6589 return mergeable_constant_section (mode, align, 0);
6592 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6594 void
6595 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6597 rtx symbol;
6598 int flags;
6600 /* Careful not to prod global register variables. */
6601 if (!MEM_P (rtl))
6602 return;
6603 symbol = XEXP (rtl, 0);
6604 if (GET_CODE (symbol) != SYMBOL_REF)
6605 return;
6607 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6608 if (TREE_CODE (decl) == FUNCTION_DECL)
6609 flags |= SYMBOL_FLAG_FUNCTION;
6610 if (targetm.binds_local_p (decl))
6611 flags |= SYMBOL_FLAG_LOCAL;
6612 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6613 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6614 else if (targetm.in_small_data_p (decl))
6615 flags |= SYMBOL_FLAG_SMALL;
6616 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6617 being PUBLIC, the thing *must* be defined in this translation unit.
6618 Prevent this buglet from being propagated into rtl code as well. */
6619 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6620 flags |= SYMBOL_FLAG_EXTERNAL;
6622 SYMBOL_REF_FLAGS (symbol) = flags;
6625 /* By default, we do nothing for encode_section_info, so we need not
6626 do anything but discard the '*' marker. */
6628 const char *
6629 default_strip_name_encoding (const char *str)
6631 return str + (*str == '*');
6634 #ifdef ASM_OUTPUT_DEF
6635 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6636 anchor relative to ".", the current section position. */
6638 void
6639 default_asm_output_anchor (rtx symbol)
6641 char buffer[100];
6643 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6644 SYMBOL_REF_BLOCK_OFFSET (symbol));
6645 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6647 #endif
6649 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6651 bool
6652 default_use_anchors_for_symbol_p (const_rtx symbol)
6654 section *sect;
6655 tree decl;
6657 /* Don't use anchors for mergeable sections. The linker might move
6658 the objects around. */
6659 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6660 if (sect->common.flags & SECTION_MERGE)
6661 return false;
6663 /* Don't use anchors for small data sections. The small data register
6664 acts as an anchor for such sections. */
6665 if (sect->common.flags & SECTION_SMALL)
6666 return false;
6668 decl = SYMBOL_REF_DECL (symbol);
6669 if (decl && DECL_P (decl))
6671 /* Don't use section anchors for decls that might be defined or
6672 usurped by other modules. */
6673 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6674 return false;
6676 /* Don't use section anchors for decls that will be placed in a
6677 small data section. */
6678 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6679 one above. The problem is that we only use SECTION_SMALL for
6680 sections that should be marked as small in the section directive. */
6681 if (targetm.in_small_data_p (decl))
6682 return false;
6684 return true;
6687 /* Return true when RESOLUTION indicate that symbol will be bound to the
6688 definition provided by current .o file. */
6690 static bool
6691 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
6693 return (resolution == LDPR_PREVAILING_DEF
6694 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6695 || resolution == LDPR_PREVAILING_DEF_IRONLY);
6698 /* Return true when RESOLUTION indicate that symbol will be bound locally
6699 within current executable or DSO. */
6701 static bool
6702 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
6704 return (resolution == LDPR_PREVAILING_DEF
6705 || resolution == LDPR_PREVAILING_DEF_IRONLY
6706 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6707 || resolution == LDPR_PREEMPTED_REG
6708 || resolution == LDPR_PREEMPTED_IR
6709 || resolution == LDPR_RESOLVED_IR
6710 || resolution == LDPR_RESOLVED_EXEC);
6713 /* Assume ELF-ish defaults, since that's pretty much the most liberal
6714 wrt cross-module name binding. */
6716 bool
6717 default_binds_local_p (const_tree exp)
6719 return default_binds_local_p_1 (exp, flag_shlib);
6722 bool
6723 default_binds_local_p_1 (const_tree exp, int shlib)
6725 bool local_p;
6726 bool resolved_locally = false;
6727 bool resolved_to_local_def = false;
6729 /* With resolution file in hands, take look into resolutions.
6730 We can't just return true for resolved_locally symbols,
6731 because dynamic linking might overwrite symbols
6732 in shared libraries. */
6733 if (TREE_CODE (exp) == VAR_DECL && TREE_PUBLIC (exp)
6734 && (TREE_STATIC (exp) || DECL_EXTERNAL (exp)))
6736 varpool_node *vnode = varpool_node::get (exp);
6737 if (vnode && (resolution_local_p (vnode->resolution) || vnode->in_other_partition))
6738 resolved_locally = true;
6739 if (vnode
6740 && resolution_to_local_definition_p (vnode->resolution))
6741 resolved_to_local_def = true;
6743 else if (TREE_CODE (exp) == FUNCTION_DECL && TREE_PUBLIC (exp))
6745 struct cgraph_node *node = cgraph_node::get (exp);
6746 if (node
6747 && (resolution_local_p (node->resolution) || node->in_other_partition))
6748 resolved_locally = true;
6749 if (node
6750 && resolution_to_local_definition_p (node->resolution))
6751 resolved_to_local_def = true;
6754 /* A non-decl is an entry in the constant pool. */
6755 if (!DECL_P (exp))
6756 local_p = true;
6757 /* Weakrefs may not bind locally, even though the weakref itself is always
6758 static and therefore local. Similarly, the resolver for ifunc functions
6759 might resolve to a non-local function.
6760 FIXME: We can resolve the weakref case more curefuly by looking at the
6761 weakref alias. */
6762 else if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
6763 || (TREE_CODE (exp) == FUNCTION_DECL
6764 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
6765 local_p = false;
6766 /* Static variables are always local. */
6767 else if (! TREE_PUBLIC (exp))
6768 local_p = true;
6769 /* A variable is local if the user has said explicitly that it will
6770 be. */
6771 else if ((DECL_VISIBILITY_SPECIFIED (exp)
6772 || resolved_to_local_def)
6773 && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6774 local_p = true;
6775 /* Variables defined outside this object might not be local. */
6776 else if (DECL_EXTERNAL (exp) && !resolved_locally)
6777 local_p = false;
6778 /* If defined in this object and visibility is not default, must be
6779 local. */
6780 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6781 local_p = true;
6782 /* Default visibility weak data can be overridden by a strong symbol
6783 in another module and so are not local. */
6784 else if (DECL_WEAK (exp)
6785 && !resolved_locally)
6786 local_p = false;
6787 /* If PIC, then assume that any global name can be overridden by
6788 symbols resolved from other modules. */
6789 else if (shlib)
6790 local_p = false;
6791 /* Uninitialized COMMON variable may be unified with symbols
6792 resolved from other modules. */
6793 else if (DECL_COMMON (exp)
6794 && !resolved_locally
6795 && (DECL_INITIAL (exp) == NULL
6796 || (!in_lto_p && DECL_INITIAL (exp) == error_mark_node)))
6797 local_p = false;
6798 /* Otherwise we're left with initialized (or non-common) global data
6799 which is of necessity defined locally. */
6800 else
6801 local_p = true;
6803 return local_p;
6806 /* Return true when references to DECL must bind to current definition in
6807 final executable.
6809 The condition is usually equivalent to whether the function binds to the
6810 current module (shared library or executable), that is to binds_local_p.
6811 We use this fact to avoid need for another target hook and implement
6812 the logic using binds_local_p and just special cases where
6813 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
6814 the weak definitions (that can be overwritten at linktime by other
6815 definition from different object file) and when resolution info is available
6816 we simply use the knowledge passed to us by linker plugin. */
6817 bool
6818 decl_binds_to_current_def_p (const_tree decl)
6820 gcc_assert (DECL_P (decl));
6821 if (!targetm.binds_local_p (decl))
6822 return false;
6823 if (!TREE_PUBLIC (decl))
6824 return true;
6825 /* When resolution is available, just use it. */
6826 if (TREE_CODE (decl) == VAR_DECL
6827 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl)))
6829 varpool_node *vnode = varpool_node::get (decl);
6830 if (vnode
6831 && vnode->resolution != LDPR_UNKNOWN)
6832 return resolution_to_local_definition_p (vnode->resolution);
6834 else if (TREE_CODE (decl) == FUNCTION_DECL)
6836 struct cgraph_node *node = cgraph_node::get (decl);
6837 if (node
6838 && node->resolution != LDPR_UNKNOWN)
6839 return resolution_to_local_definition_p (node->resolution);
6841 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
6842 binds locally but still can be overwritten), DECL_COMMON (can be merged
6843 with a non-common definition somewhere in the same module) or
6844 DECL_EXTERNAL.
6845 This rely on fact that binds_local_p behave as decl_replaceable_p
6846 for all other declaration types. */
6847 if (DECL_WEAK (decl))
6848 return false;
6849 if (DECL_COMMON (decl)
6850 && (DECL_INITIAL (decl) == NULL
6851 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
6852 return false;
6853 if (DECL_EXTERNAL (decl))
6854 return false;
6855 return true;
6858 /* A replaceable function or variable is one which may be replaced
6859 at link-time with an entirely different definition, provided that the
6860 replacement has the same type. For example, functions declared
6861 with __attribute__((weak)) on most systems are replaceable.
6863 COMDAT functions are not replaceable, since all definitions of the
6864 function must be equivalent. It is important that COMDAT functions
6865 not be treated as replaceable so that use of C++ template
6866 instantiations is not penalized. */
6868 bool
6869 decl_replaceable_p (tree decl)
6871 gcc_assert (DECL_P (decl));
6872 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
6873 return false;
6874 if (!flag_semantic_interposition
6875 && !DECL_WEAK (decl))
6876 return false;
6877 return !decl_binds_to_current_def_p (decl);
6880 /* Default function to output code that will globalize a label. A
6881 target must define GLOBAL_ASM_OP or provide its own function to
6882 globalize a label. */
6883 #ifdef GLOBAL_ASM_OP
6884 void
6885 default_globalize_label (FILE * stream, const char *name)
6887 fputs (GLOBAL_ASM_OP, stream);
6888 assemble_name (stream, name);
6889 putc ('\n', stream);
6891 #endif /* GLOBAL_ASM_OP */
6893 /* Default function to output code that will globalize a declaration. */
6894 void
6895 default_globalize_decl_name (FILE * stream, tree decl)
6897 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
6898 targetm.asm_out.globalize_label (stream, name);
6901 /* Default function to output a label for unwind information. The
6902 default is to do nothing. A target that needs nonlocal labels for
6903 unwind information must provide its own function to do this. */
6904 void
6905 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
6906 tree decl ATTRIBUTE_UNUSED,
6907 int for_eh ATTRIBUTE_UNUSED,
6908 int empty ATTRIBUTE_UNUSED)
6912 /* Default function to output a label to divide up the exception table.
6913 The default is to do nothing. A target that needs/wants to divide
6914 up the table must provide it's own function to do this. */
6915 void
6916 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
6920 /* This is how to output an internal numbered label where PREFIX is
6921 the class of label and LABELNO is the number within the class. */
6923 void
6924 default_generate_internal_label (char *buf, const char *prefix,
6925 unsigned long labelno)
6927 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6930 /* This is how to output an internal numbered label where PREFIX is
6931 the class of label and LABELNO is the number within the class. */
6933 void
6934 default_internal_label (FILE *stream, const char *prefix,
6935 unsigned long labelno)
6937 char *const buf = (char *) alloca (40 + strlen (prefix));
6938 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6939 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
6943 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
6945 void
6946 default_asm_declare_constant_name (FILE *file, const char *name,
6947 const_tree exp ATTRIBUTE_UNUSED,
6948 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
6950 assemble_label (file, name);
6953 /* This is the default behavior at the beginning of a file. It's
6954 controlled by two other target-hook toggles. */
6955 void
6956 default_file_start (void)
6958 if (targetm.asm_file_start_app_off
6959 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
6960 fputs (ASM_APP_OFF, asm_out_file);
6962 if (targetm.asm_file_start_file_directive)
6963 output_file_directive (asm_out_file, main_input_filename);
6966 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
6967 which emits a special section directive used to indicate whether or
6968 not this object file needs an executable stack. This is primarily
6969 a GNU extension to ELF but could be used on other targets. */
6971 int trampolines_created;
6973 void
6974 file_end_indicate_exec_stack (void)
6976 unsigned int flags = SECTION_DEBUG;
6977 if (trampolines_created)
6978 flags |= SECTION_CODE;
6980 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
6983 /* Emit a special section directive to indicate that this object file
6984 was compiled with -fsplit-stack. This is used to let the linker
6985 detect calls between split-stack code and non-split-stack code, so
6986 that it can modify the split-stack code to allocate a sufficiently
6987 large stack. We emit another special section if there are any
6988 functions in this file which have the no_split_stack attribute, to
6989 prevent the linker from warning about being unable to convert the
6990 functions if they call non-split-stack code. */
6992 void
6993 file_end_indicate_split_stack (void)
6995 if (flag_split_stack)
6997 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
6998 NULL));
6999 if (saw_no_split_stack)
7000 switch_to_section (get_section (".note.GNU-no-split-stack",
7001 SECTION_DEBUG, NULL));
7005 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
7006 a get_unnamed_section callback. */
7008 void
7009 output_section_asm_op (const void *directive)
7011 fprintf (asm_out_file, "%s\n", (const char *) directive);
7014 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
7015 the current section is NEW_SECTION. */
7017 void
7018 switch_to_section (section *new_section)
7020 if (in_section == new_section)
7021 return;
7023 if (new_section->common.flags & SECTION_FORGET)
7024 in_section = NULL;
7025 else
7026 in_section = new_section;
7028 switch (SECTION_STYLE (new_section))
7030 case SECTION_NAMED:
7031 targetm.asm_out.named_section (new_section->named.name,
7032 new_section->named.common.flags,
7033 new_section->named.decl);
7034 break;
7036 case SECTION_UNNAMED:
7037 new_section->unnamed.callback (new_section->unnamed.data);
7038 break;
7040 case SECTION_NOSWITCH:
7041 gcc_unreachable ();
7042 break;
7045 new_section->common.flags |= SECTION_DECLARED;
7048 /* If block symbol SYMBOL has not yet been assigned an offset, place
7049 it at the end of its block. */
7051 void
7052 place_block_symbol (rtx symbol)
7054 unsigned HOST_WIDE_INT size, mask, offset;
7055 struct constant_descriptor_rtx *desc;
7056 unsigned int alignment;
7057 struct object_block *block;
7058 tree decl;
7060 gcc_assert (SYMBOL_REF_BLOCK (symbol));
7061 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7062 return;
7064 /* Work out the symbol's size and alignment. */
7065 if (CONSTANT_POOL_ADDRESS_P (symbol))
7067 desc = SYMBOL_REF_CONSTANT (symbol);
7068 alignment = desc->align;
7069 size = GET_MODE_SIZE (desc->mode);
7071 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7073 decl = SYMBOL_REF_DECL (symbol);
7074 alignment = DECL_ALIGN (decl);
7075 size = get_constant_size (DECL_INITIAL (decl));
7076 if ((flag_sanitize & SANITIZE_ADDRESS)
7077 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7078 && asan_protect_global (DECL_INITIAL (decl)))
7079 size += asan_red_zone_size (size);
7081 else
7083 struct symtab_node *snode;
7084 decl = SYMBOL_REF_DECL (symbol);
7086 snode = symtab_node::get (decl);
7087 if (snode->alias)
7089 rtx target = DECL_RTL (snode->ultimate_alias_target ()->decl);
7091 place_block_symbol (target);
7092 SYMBOL_REF_BLOCK_OFFSET (symbol) = SYMBOL_REF_BLOCK_OFFSET (target);
7093 return;
7095 alignment = get_variable_align (decl);
7096 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7097 if ((flag_sanitize & SANITIZE_ADDRESS)
7098 && asan_protect_global (decl))
7100 size += asan_red_zone_size (size);
7101 alignment = MAX (alignment,
7102 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7106 /* Calculate the object's offset from the start of the block. */
7107 block = SYMBOL_REF_BLOCK (symbol);
7108 mask = alignment / BITS_PER_UNIT - 1;
7109 offset = (block->size + mask) & ~mask;
7110 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7112 /* Record the block's new alignment and size. */
7113 block->alignment = MAX (block->alignment, alignment);
7114 block->size = offset + size;
7116 vec_safe_push (block->objects, symbol);
7119 /* Return the anchor that should be used to address byte offset OFFSET
7120 from the first object in BLOCK. MODEL is the TLS model used
7121 to access it. */
7124 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7125 enum tls_model model)
7127 char label[100];
7128 unsigned int begin, middle, end;
7129 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7130 rtx anchor;
7132 /* Work out the anchor's offset. Use an offset of 0 for the first
7133 anchor so that we don't pessimize the case where we take the address
7134 of a variable at the beginning of the block. This is particularly
7135 useful when a block has only one variable assigned to it.
7137 We try to place anchors RANGE bytes apart, so there can then be
7138 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7139 a ptr_mode offset. With some target settings, the lowest such
7140 anchor might be out of range for the lowest ptr_mode offset;
7141 likewise the highest anchor for the highest offset. Use anchors
7142 at the extreme ends of the ptr_mode range in such cases.
7144 All arithmetic uses unsigned integers in order to avoid
7145 signed overflow. */
7146 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7147 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7148 range = max_offset - min_offset + 1;
7149 if (range == 0)
7150 offset = 0;
7151 else
7153 bias = 1 << (GET_MODE_BITSIZE (ptr_mode) - 1);
7154 if (offset < 0)
7156 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7157 delta -= delta % range;
7158 if (delta > bias)
7159 delta = bias;
7160 offset = (HOST_WIDE_INT) (-delta);
7162 else
7164 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7165 delta -= delta % range;
7166 if (delta > bias - 1)
7167 delta = bias - 1;
7168 offset = (HOST_WIDE_INT) delta;
7172 /* Do a binary search to see if there's already an anchor we can use.
7173 Set BEGIN to the new anchor's index if not. */
7174 begin = 0;
7175 end = vec_safe_length (block->anchors);
7176 while (begin != end)
7178 middle = (end + begin) / 2;
7179 anchor = (*block->anchors)[middle];
7180 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7181 end = middle;
7182 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7183 begin = middle + 1;
7184 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7185 end = middle;
7186 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7187 begin = middle + 1;
7188 else
7189 return anchor;
7192 /* Create a new anchor with a unique label. */
7193 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7194 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7195 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7196 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7198 /* Insert it at index BEGIN. */
7199 vec_safe_insert (block->anchors, begin, anchor);
7200 return anchor;
7203 /* Output the objects in BLOCK. */
7205 static void
7206 output_object_block (struct object_block *block)
7208 struct constant_descriptor_rtx *desc;
7209 unsigned int i;
7210 HOST_WIDE_INT offset;
7211 tree decl;
7212 rtx symbol;
7214 if (!block->objects)
7215 return;
7217 /* Switch to the section and make sure that the first byte is
7218 suitably aligned. */
7219 switch_to_section (block->sect);
7220 assemble_align (block->alignment);
7222 /* Define the values of all anchors relative to the current section
7223 position. */
7224 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7225 targetm.asm_out.output_anchor (symbol);
7227 /* Output the objects themselves. */
7228 offset = 0;
7229 FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7231 /* Move to the object's offset, padding with zeros if necessary. */
7232 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7233 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7234 if (CONSTANT_POOL_ADDRESS_P (symbol))
7236 desc = SYMBOL_REF_CONSTANT (symbol);
7237 output_constant_pool_1 (desc, 1);
7238 offset += GET_MODE_SIZE (desc->mode);
7240 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7242 HOST_WIDE_INT size;
7243 decl = SYMBOL_REF_DECL (symbol);
7244 assemble_constant_contents (DECL_INITIAL (decl), XSTR (symbol, 0),
7245 DECL_ALIGN (decl));
7246 size = get_constant_size (DECL_INITIAL (decl));
7247 offset += size;
7248 if ((flag_sanitize & SANITIZE_ADDRESS)
7249 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7250 && asan_protect_global (DECL_INITIAL (decl)))
7252 size = asan_red_zone_size (size);
7253 assemble_zeros (size);
7254 offset += size;
7257 else
7259 HOST_WIDE_INT size;
7260 decl = SYMBOL_REF_DECL (symbol);
7261 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7262 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7263 offset += size;
7264 if ((flag_sanitize & SANITIZE_ADDRESS)
7265 && asan_protect_global (decl))
7267 size = asan_red_zone_size (size);
7268 assemble_zeros (size);
7269 offset += size;
7275 /* A htab_traverse callback used to call output_object_block for
7276 each member of object_block_htab. */
7278 static int
7279 output_object_block_htab (void **slot, void *data ATTRIBUTE_UNUSED)
7281 output_object_block ((struct object_block *) (*slot));
7282 return 1;
7285 /* Output the definitions of all object_blocks. */
7287 void
7288 output_object_blocks (void)
7290 htab_traverse (object_block_htab, output_object_block_htab, NULL);
7293 /* This function provides a possible implementation of the
7294 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7295 by -frecord-gcc-switches it creates a new mergeable, string section in the
7296 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7297 contains the switches in ASCII format.
7299 FIXME: This code does not correctly handle double quote characters
7300 that appear inside strings, (it strips them rather than preserving them).
7301 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7302 characters - instead it treats them as sub-string separators. Since
7303 we want to emit NUL strings terminators into the object file we have to use
7304 ASM_OUTPUT_SKIP. */
7307 elf_record_gcc_switches (print_switch_type type, const char * name)
7309 switch (type)
7311 case SWITCH_TYPE_PASSED:
7312 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7313 ASM_OUTPUT_SKIP (asm_out_file, (unsigned HOST_WIDE_INT) 1);
7314 break;
7316 case SWITCH_TYPE_DESCRIPTIVE:
7317 if (name == NULL)
7319 /* Distinguish between invocations where name is NULL. */
7320 static bool started = false;
7322 if (!started)
7324 section * sec;
7326 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7327 SECTION_DEBUG
7328 | SECTION_MERGE
7329 | SECTION_STRINGS
7330 | (SECTION_ENTSIZE & 1),
7331 NULL);
7332 switch_to_section (sec);
7333 started = true;
7337 default:
7338 break;
7341 /* The return value is currently ignored by the caller, but must be 0.
7342 For -fverbose-asm the return value would be the number of characters
7343 emitted into the assembler file. */
7344 return 0;
7347 /* Emit text to declare externally defined symbols. It is needed to
7348 properly support non-default visibility. */
7349 void
7350 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7351 tree decl,
7352 const char *name ATTRIBUTE_UNUSED)
7354 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7355 set in order to avoid putting out names that are never really
7356 used. */
7357 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7358 && targetm.binds_local_p (decl))
7359 maybe_assemble_visibility (decl);
7362 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7364 void
7365 default_asm_output_source_filename (FILE *file, const char *name)
7367 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7368 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7369 #else
7370 fprintf (file, "\t.file\t");
7371 output_quoted_string (file, name);
7372 putc ('\n', file);
7373 #endif
7376 /* Output a file name in the form wanted by System V. */
7378 void
7379 output_file_directive (FILE *asm_file, const char *input_name)
7381 int len;
7382 const char *na;
7384 if (input_name == NULL)
7385 input_name = "<stdin>";
7386 else
7387 input_name = remap_debug_filename (input_name);
7389 len = strlen (input_name);
7390 na = input_name + len;
7392 /* NA gets INPUT_NAME sans directory names. */
7393 while (na > input_name)
7395 if (IS_DIR_SEPARATOR (na[-1]))
7396 break;
7397 na--;
7400 targetm.asm_out.output_source_filename (asm_file, na);
7403 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7404 EXP. */
7406 make_debug_expr_from_rtl (const_rtx exp)
7408 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7409 enum machine_mode mode = GET_MODE (exp);
7410 rtx dval;
7412 DECL_ARTIFICIAL (ddecl) = 1;
7413 if (REG_P (exp) && REG_EXPR (exp))
7414 type = TREE_TYPE (REG_EXPR (exp));
7415 else if (MEM_P (exp) && MEM_EXPR (exp))
7416 type = TREE_TYPE (MEM_EXPR (exp));
7417 else
7418 type = NULL_TREE;
7419 if (type && TYPE_MODE (type) == mode)
7420 TREE_TYPE (ddecl) = type;
7421 else
7422 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7423 DECL_MODE (ddecl) = mode;
7424 dval = gen_rtx_DEBUG_EXPR (mode);
7425 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7426 SET_DECL_RTL (ddecl, dval);
7427 return dval;
7430 #ifdef ELF_ASCII_ESCAPES
7431 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7433 void
7434 default_elf_asm_output_limited_string (FILE *f, const char *s)
7436 int escape;
7437 unsigned char c;
7439 fputs (STRING_ASM_OP, f);
7440 putc ('"', f);
7441 while (*s != '\0')
7443 c = *s;
7444 escape = ELF_ASCII_ESCAPES[c];
7445 switch (escape)
7447 case 0:
7448 putc (c, f);
7449 break;
7450 case 1:
7451 /* TODO: Print in hex with fast function, important for -flto. */
7452 fprintf (f, "\\%03o", c);
7453 break;
7454 default:
7455 putc ('\\', f);
7456 putc (escape, f);
7457 break;
7459 s++;
7461 putc ('\"', f);
7462 putc ('\n', f);
7465 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7467 void
7468 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7470 const char *limit = s + len;
7471 const char *last_null = NULL;
7472 unsigned bytes_in_chunk = 0;
7473 unsigned char c;
7474 int escape;
7476 for (; s < limit; s++)
7478 const char *p;
7480 if (bytes_in_chunk >= 60)
7482 putc ('\"', f);
7483 putc ('\n', f);
7484 bytes_in_chunk = 0;
7487 if (s > last_null)
7489 for (p = s; p < limit && *p != '\0'; p++)
7490 continue;
7491 last_null = p;
7493 else
7494 p = last_null;
7496 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7498 if (bytes_in_chunk > 0)
7500 putc ('\"', f);
7501 putc ('\n', f);
7502 bytes_in_chunk = 0;
7505 default_elf_asm_output_limited_string (f, s);
7506 s = p;
7508 else
7510 if (bytes_in_chunk == 0)
7511 fputs (ASCII_DATA_ASM_OP "\"", f);
7513 c = *s;
7514 escape = ELF_ASCII_ESCAPES[c];
7515 switch (escape)
7517 case 0:
7518 putc (c, f);
7519 bytes_in_chunk++;
7520 break;
7521 case 1:
7522 /* TODO: Print in hex with fast function, important for -flto. */
7523 fprintf (f, "\\%03o", c);
7524 bytes_in_chunk += 4;
7525 break;
7526 default:
7527 putc ('\\', f);
7528 putc (escape, f);
7529 bytes_in_chunk += 2;
7530 break;
7536 if (bytes_in_chunk > 0)
7538 putc ('\"', f);
7539 putc ('\n', f);
7542 #endif
7544 static GTY(()) section *elf_init_array_section;
7545 static GTY(()) section *elf_fini_array_section;
7547 static section *
7548 get_elf_initfini_array_priority_section (int priority,
7549 bool constructor_p)
7551 section *sec;
7552 if (priority != DEFAULT_INIT_PRIORITY)
7554 char buf[18];
7555 sprintf (buf, "%s.%.5u",
7556 constructor_p ? ".init_array" : ".fini_array",
7557 priority);
7558 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7560 else
7562 if (constructor_p)
7564 if (elf_init_array_section == NULL)
7565 elf_init_array_section
7566 = get_section (".init_array",
7567 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7568 sec = elf_init_array_section;
7570 else
7572 if (elf_fini_array_section == NULL)
7573 elf_fini_array_section
7574 = get_section (".fini_array",
7575 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7576 sec = elf_fini_array_section;
7579 return sec;
7582 /* Use .init_array section for constructors. */
7584 void
7585 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7587 section *sec = get_elf_initfini_array_priority_section (priority,
7588 true);
7589 assemble_addr_to_section (symbol, sec);
7592 /* Use .fini_array section for destructors. */
7594 void
7595 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7597 section *sec = get_elf_initfini_array_priority_section (priority,
7598 false);
7599 assemble_addr_to_section (symbol, sec);
7602 /* Default TARGET_ASM_OUTPUT_IDENT hook.
7604 This is a bit of a cheat. The real default is a no-op, but this
7605 hook is the default for all targets with a .ident directive. */
7607 void
7608 default_asm_output_ident_directive (const char *ident_str)
7610 const char *ident_asm_op = "\t.ident\t";
7612 /* If we are still in the front end, do not write out the string
7613 to asm_out_file. Instead, add a fake top-level asm statement.
7614 This allows the front ends to use this hook without actually
7615 writing to asm_out_file, to handle #ident or Pragma Ident. */
7616 if (symtab->state == PARSING)
7618 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
7619 symtab->finalize_toplevel_asm (build_string (strlen (buf), buf));
7621 else
7622 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
7625 #include "gt-varasm.h"