configure.ac: Move AM_ENABLE_MULTILIB before AC_PROG_CC.
[official-gcc.git] / gcc / varasm.c
blob36c3633deb4cb4c17af2a810da3753205dc09c9d
1 /* Output variables, constants and external declarations, for GNU compiler.
2 Copyright (C) 1987-2015 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 "hash-set.h"
34 #include "machmode.h"
35 #include "vec.h"
36 #include "double-int.h"
37 #include "input.h"
38 #include "alias.h"
39 #include "symtab.h"
40 #include "wide-int.h"
41 #include "inchash.h"
42 #include "tree.h"
43 #include "fold-const.h"
44 #include "stor-layout.h"
45 #include "stringpool.h"
46 #include "varasm.h"
47 #include "flags.h"
48 #include "hard-reg-set.h"
49 #include "function.h"
50 #include "hashtab.h"
51 #include "statistics.h"
52 #include "real.h"
53 #include "fixed-value.h"
54 #include "insn-config.h"
55 #include "expmed.h"
56 #include "dojump.h"
57 #include "explow.h"
58 #include "calls.h"
59 #include "emit-rtl.h"
60 #include "stmt.h"
61 #include "expr.h"
62 #include "regs.h"
63 #include "output.h"
64 #include "diagnostic-core.h"
65 #include "ggc.h"
66 #include "langhooks.h"
67 #include "tm_p.h"
68 #include "debug.h"
69 #include "target.h"
70 #include "common/common-target.h"
71 #include "targhooks.h"
72 #include "predict.h"
73 #include "dominance.h"
74 #include "cfg.h"
75 #include "basic-block.h"
76 #include "hash-map.h"
77 #include "is-a.h"
78 #include "plugin-api.h"
79 #include "ipa-ref.h"
80 #include "cgraph.h"
81 #include "asan.h"
82 #include "rtl-iter.h"
83 #include "tree-chkp.h"
85 #ifdef XCOFF_DEBUGGING_INFO
86 #include "xcoffout.h" /* Needed for external data
87 declarations for e.g. AIX 4.x. */
88 #endif
90 /* The (assembler) name of the first globally-visible object output. */
91 extern GTY(()) const char *first_global_object_name;
92 extern GTY(()) const char *weak_global_object_name;
94 const char *first_global_object_name;
95 const char *weak_global_object_name;
97 struct addr_const;
98 struct constant_descriptor_rtx;
99 struct rtx_constant_pool;
101 #define n_deferred_constants (crtl->varasm.deferred_constants)
103 /* Number for making the label on the next
104 constant that is stored in memory. */
106 static GTY(()) int const_labelno;
108 /* Carry information from ASM_DECLARE_OBJECT_NAME
109 to ASM_FINISH_DECLARE_OBJECT. */
111 int size_directive_output;
113 /* The last decl for which assemble_variable was called,
114 if it did ASM_DECLARE_OBJECT_NAME.
115 If the last call to assemble_variable didn't do that,
116 this holds 0. */
118 tree last_assemble_variable_decl;
120 /* The following global variable indicates if the first basic block
121 in a function belongs to the cold partition or not. */
123 bool first_function_block_is_cold;
125 /* Whether we saw any functions with no_split_stack. */
127 static bool saw_no_split_stack;
129 static const char *strip_reg_name (const char *);
130 static int contains_pointers_p (tree);
131 #ifdef ASM_OUTPUT_EXTERNAL
132 static bool incorporeal_function_p (tree);
133 #endif
134 static void decode_addr_const (tree, struct addr_const *);
135 static hashval_t const_hash_1 (const tree);
136 static int compare_constant (const tree, const tree);
137 static void output_constant_def_contents (rtx);
138 static void output_addressed_constants (tree);
139 static unsigned HOST_WIDE_INT output_constant (tree, unsigned HOST_WIDE_INT,
140 unsigned int);
141 static void globalize_decl (tree);
142 static bool decl_readonly_section_1 (enum section_category);
143 #ifdef BSS_SECTION_ASM_OP
144 #ifdef ASM_OUTPUT_ALIGNED_BSS
145 static void asm_output_aligned_bss (FILE *, tree, const char *,
146 unsigned HOST_WIDE_INT, int)
147 ATTRIBUTE_UNUSED;
148 #endif
149 #endif /* BSS_SECTION_ASM_OP */
150 static void mark_weak (tree);
151 static void output_constant_pool (const char *, tree);
153 /* Well-known sections, each one associated with some sort of *_ASM_OP. */
154 section *text_section;
155 section *data_section;
156 section *readonly_data_section;
157 section *sdata_section;
158 section *ctors_section;
159 section *dtors_section;
160 section *bss_section;
161 section *sbss_section;
163 /* Various forms of common section. All are guaranteed to be nonnull. */
164 section *tls_comm_section;
165 section *comm_section;
166 section *lcomm_section;
168 /* A SECTION_NOSWITCH section used for declaring global BSS variables.
169 May be null. */
170 section *bss_noswitch_section;
172 /* The section that holds the main exception table, when known. The section
173 is set either by the target's init_sections hook or by the first call to
174 switch_to_exception_section. */
175 section *exception_section;
177 /* The section that holds the DWARF2 frame unwind information, when known.
178 The section is set either by the target's init_sections hook or by the
179 first call to switch_to_eh_frame_section. */
180 section *eh_frame_section;
182 /* asm_out_file's current section. This is NULL if no section has yet
183 been selected or if we lose track of what the current section is. */
184 section *in_section;
186 /* True if code for the current function is currently being directed
187 at the cold section. */
188 bool in_cold_section_p;
190 /* A linked list of all the unnamed sections. */
191 static GTY(()) section *unnamed_sections;
193 /* Return a nonzero value if DECL has a section attribute. */
194 #define IN_NAMED_SECTION(DECL) \
195 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \
196 && DECL_SECTION_NAME (DECL) != NULL)
198 struct section_hasher : ggc_hasher<section *>
200 typedef const char *compare_type;
202 static hashval_t hash (section *);
203 static bool equal (section *, const char *);
206 /* Hash table of named sections. */
207 static GTY(()) hash_table<section_hasher> *section_htab;
209 struct object_block_hasher : ggc_hasher<object_block *>
211 typedef const section *compare_type;
213 static hashval_t hash (object_block *);
214 static bool equal (object_block *, const section *);
217 /* A table of object_blocks, indexed by section. */
218 static GTY(()) hash_table<object_block_hasher> *object_block_htab;
220 /* The next number to use for internal anchor labels. */
221 static GTY(()) int anchor_labelno;
223 /* A pool of constants that can be shared between functions. */
224 static GTY(()) struct rtx_constant_pool *shared_constant_pool;
226 /* Helper routines for maintaining section_htab. */
228 bool
229 section_hasher::equal (section *old, const char *new_name)
231 return strcmp (old->named.name, new_name) == 0;
234 hashval_t
235 section_hasher::hash (section *old)
237 return htab_hash_string (old->named.name);
240 /* Return a hash value for section SECT. */
242 static hashval_t
243 hash_section (section *sect)
245 if (sect->common.flags & SECTION_NAMED)
246 return htab_hash_string (sect->named.name);
247 return sect->common.flags;
250 /* Helper routines for maintaining object_block_htab. */
252 inline bool
253 object_block_hasher::equal (object_block *old, const section *new_section)
255 return old->sect == new_section;
258 hashval_t
259 object_block_hasher::hash (object_block *old)
261 return hash_section (old->sect);
264 /* Return a new unnamed section with the given fields. */
266 section *
267 get_unnamed_section (unsigned int flags, void (*callback) (const void *),
268 const void *data)
270 section *sect;
272 sect = ggc_alloc<section> ();
273 sect->unnamed.common.flags = flags | SECTION_UNNAMED;
274 sect->unnamed.callback = callback;
275 sect->unnamed.data = data;
276 sect->unnamed.next = unnamed_sections;
278 unnamed_sections = sect;
279 return sect;
282 /* Return a SECTION_NOSWITCH section with the given fields. */
284 static section *
285 get_noswitch_section (unsigned int flags, noswitch_section_callback callback)
287 section *sect;
289 sect = ggc_alloc<section> ();
290 sect->noswitch.common.flags = flags | SECTION_NOSWITCH;
291 sect->noswitch.callback = callback;
293 return sect;
296 /* Return the named section structure associated with NAME. Create
297 a new section with the given fields if no such structure exists. */
299 section *
300 get_section (const char *name, unsigned int flags, tree decl)
302 section *sect, **slot;
304 slot = section_htab->find_slot_with_hash (name, htab_hash_string (name),
305 INSERT);
306 flags |= SECTION_NAMED;
307 if (*slot == NULL)
309 sect = ggc_alloc<section> ();
310 sect->named.common.flags = flags;
311 sect->named.name = ggc_strdup (name);
312 sect->named.decl = decl;
313 *slot = sect;
315 else
317 sect = *slot;
318 if ((sect->common.flags & ~SECTION_DECLARED) != flags
319 && ((sect->common.flags | flags) & SECTION_OVERRIDE) == 0)
321 /* It is fine if one of the section flags is
322 SECTION_WRITE | SECTION_RELRO and the other has none of these
323 flags (i.e. read-only) in named sections and either the
324 section hasn't been declared yet or has been declared as writable.
325 In that case just make sure the resulting flags are
326 SECTION_WRITE | SECTION_RELRO, ie. writable only because of
327 relocations. */
328 if (((sect->common.flags ^ flags) & (SECTION_WRITE | SECTION_RELRO))
329 == (SECTION_WRITE | SECTION_RELRO)
330 && (sect->common.flags
331 & ~(SECTION_DECLARED | SECTION_WRITE | SECTION_RELRO))
332 == (flags & ~(SECTION_WRITE | SECTION_RELRO))
333 && ((sect->common.flags & SECTION_DECLARED) == 0
334 || (sect->common.flags & SECTION_WRITE)))
336 sect->common.flags |= (SECTION_WRITE | SECTION_RELRO);
337 return sect;
339 /* Sanity check user variables for flag changes. */
340 if (sect->named.decl != NULL
341 && DECL_P (sect->named.decl)
342 && decl != sect->named.decl)
344 if (decl != NULL && DECL_P (decl))
345 error ("%+D causes a section type conflict with %D",
346 decl, sect->named.decl);
347 else
348 error ("section type conflict with %D", sect->named.decl);
349 inform (DECL_SOURCE_LOCATION (sect->named.decl),
350 "%qD was declared here", sect->named.decl);
352 else if (decl != NULL && DECL_P (decl))
353 error ("%+D causes a section type conflict", decl);
354 else
355 error ("section type conflict");
356 /* Make sure we don't error about one section multiple times. */
357 sect->common.flags |= SECTION_OVERRIDE;
360 return sect;
363 /* Return true if the current compilation mode benefits from having
364 objects grouped into blocks. */
366 static bool
367 use_object_blocks_p (void)
369 return flag_section_anchors;
372 /* Return the object_block structure for section SECT. Create a new
373 structure if we haven't created one already. Return null if SECT
374 itself is null. */
376 static struct object_block *
377 get_block_for_section (section *sect)
379 struct object_block *block;
381 if (sect == NULL)
382 return NULL;
384 object_block **slot
385 = object_block_htab->find_slot_with_hash (sect, hash_section (sect),
386 INSERT);
387 block = *slot;
388 if (block == NULL)
390 block = ggc_cleared_alloc<object_block> ();
391 block->sect = sect;
392 *slot = block;
394 return block;
397 /* Create a symbol with label LABEL and place it at byte offset
398 OFFSET in BLOCK. OFFSET can be negative if the symbol's offset
399 is not yet known. LABEL must be a garbage-collected string. */
401 static rtx
402 create_block_symbol (const char *label, struct object_block *block,
403 HOST_WIDE_INT offset)
405 rtx symbol;
406 unsigned int size;
408 /* Create the extended SYMBOL_REF. */
409 size = RTX_HDR_SIZE + sizeof (struct block_symbol);
410 symbol = (rtx) ggc_internal_alloc (size);
412 /* Initialize the normal SYMBOL_REF fields. */
413 memset (symbol, 0, size);
414 PUT_CODE (symbol, SYMBOL_REF);
415 PUT_MODE (symbol, Pmode);
416 XSTR (symbol, 0) = label;
417 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_HAS_BLOCK_INFO;
419 /* Initialize the block_symbol stuff. */
420 SYMBOL_REF_BLOCK (symbol) = block;
421 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
423 return symbol;
426 /* Return a section with a particular name and with whatever SECTION_*
427 flags section_type_flags deems appropriate. The name of the section
428 is taken from NAME if nonnull, otherwise it is taken from DECL's
429 DECL_SECTION_NAME. DECL is the decl associated with the section
430 (see the section comment for details) and RELOC is as for
431 section_type_flags. */
433 section *
434 get_named_section (tree decl, const char *name, int reloc)
436 unsigned int flags;
438 if (name == NULL)
440 gcc_assert (decl && DECL_P (decl) && DECL_SECTION_NAME (decl));
441 name = DECL_SECTION_NAME (decl);
444 flags = targetm.section_type_flags (decl, name, reloc);
445 return get_section (name, flags, decl);
448 /* Worker for resolve_unique_section. */
450 static bool
451 set_implicit_section (struct symtab_node *n, void *data ATTRIBUTE_UNUSED)
453 n->implicit_section = true;
454 return false;
457 /* If required, set DECL_SECTION_NAME to a unique name. */
459 void
460 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
461 int flag_function_or_data_sections)
463 if (DECL_SECTION_NAME (decl) == NULL
464 && targetm_common.have_named_sections
465 && (flag_function_or_data_sections
466 || DECL_COMDAT_GROUP (decl)))
468 targetm.asm_out.unique_section (decl, reloc);
469 if (DECL_SECTION_NAME (decl))
470 symtab_node::get (decl)->call_for_symbol_and_aliases
471 (set_implicit_section, NULL, true);
475 #ifdef BSS_SECTION_ASM_OP
477 #ifdef ASM_OUTPUT_ALIGNED_BSS
479 /* Utility function for targets to use in implementing
480 ASM_OUTPUT_ALIGNED_BSS.
481 ??? It is believed that this function will work in most cases so such
482 support is localized here. */
484 static void
485 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
486 const char *name, unsigned HOST_WIDE_INT size,
487 int align)
489 switch_to_section (bss_section);
490 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
491 #ifdef ASM_DECLARE_OBJECT_NAME
492 last_assemble_variable_decl = decl;
493 ASM_DECLARE_OBJECT_NAME (file, name, decl);
494 #else
495 /* Standard thing is just output label for the object. */
496 ASM_OUTPUT_LABEL (file, name);
497 #endif /* ASM_DECLARE_OBJECT_NAME */
498 ASM_OUTPUT_SKIP (file, size ? size : 1);
501 #endif
503 #endif /* BSS_SECTION_ASM_OP */
505 #ifndef USE_SELECT_SECTION_FOR_FUNCTIONS
506 /* Return the hot section for function DECL. Return text_section for
507 null DECLs. */
509 static section *
510 hot_function_section (tree decl)
512 if (decl != NULL_TREE
513 && DECL_SECTION_NAME (decl) != NULL
514 && targetm_common.have_named_sections)
515 return get_named_section (decl, NULL, 0);
516 else
517 return text_section;
519 #endif
521 /* Return section for TEXT_SECTION_NAME if DECL or DECL_SECTION_NAME (DECL)
522 is NULL.
524 When DECL_SECTION_NAME is non-NULL and it is implicit section and
525 NAMED_SECTION_SUFFIX is non-NULL, then produce section called
526 concatenate the name with NAMED_SECTION_SUFFIX.
527 Otherwise produce "TEXT_SECTION_NAME.IMPLICIT_NAME". */
529 section *
530 get_named_text_section (tree decl,
531 const char *text_section_name,
532 const char *named_section_suffix)
534 if (decl && DECL_SECTION_NAME (decl))
536 if (named_section_suffix)
538 const char *dsn = DECL_SECTION_NAME (decl);
539 const char *stripped_name;
540 char *name, *buffer;
542 name = (char *) alloca (strlen (dsn) + 1);
543 memcpy (name, dsn,
544 strlen (dsn) + 1);
546 stripped_name = targetm.strip_name_encoding (name);
548 buffer = ACONCAT ((stripped_name, named_section_suffix, NULL));
549 return get_named_section (decl, buffer, 0);
551 else if (symtab_node::get (decl)->implicit_section)
553 const char *name;
555 /* Do not try to split gnu_linkonce functions. This gets somewhat
556 slipperly. */
557 if (DECL_COMDAT_GROUP (decl) && !HAVE_COMDAT_GROUP)
558 return NULL;
559 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
560 name = targetm.strip_name_encoding (name);
561 return get_named_section (decl, ACONCAT ((text_section_name, ".",
562 name, NULL)), 0);
564 else
565 return NULL;
567 return get_named_section (decl, text_section_name, 0);
570 /* Choose named function section based on its frequency. */
572 section *
573 default_function_section (tree decl, enum node_frequency freq,
574 bool startup, bool exit)
576 #if defined HAVE_LD_EH_GC_SECTIONS && defined HAVE_LD_EH_GC_SECTIONS_BUG
577 /* Old GNU linkers have buggy --gc-section support, which sometimes
578 results in .gcc_except_table* sections being garbage collected. */
579 if (decl
580 && symtab_node::get (decl)->implicit_section)
581 return NULL;
582 #endif
584 if (!flag_reorder_functions
585 || !targetm_common.have_named_sections)
586 return NULL;
587 /* Startup code should go to startup subsection unless it is
588 unlikely executed (this happens especially with function splitting
589 where we can split away unnecessary parts of static constructors. */
590 if (startup && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
592 /* If we do have a profile or(and) LTO phase is executed, we do not need
593 these ELF section. */
594 if (!in_lto_p || !flag_profile_values)
595 return get_named_text_section (decl, ".text.startup", NULL);
596 else
597 return NULL;
600 /* Similarly for exit. */
601 if (exit && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
602 return get_named_text_section (decl, ".text.exit", NULL);
604 /* Group cold functions together, similarly for hot code. */
605 switch (freq)
607 case NODE_FREQUENCY_UNLIKELY_EXECUTED:
608 return get_named_text_section (decl, ".text.unlikely", NULL);
609 case NODE_FREQUENCY_HOT:
610 /* If we do have a profile or(and) LTO phase is executed, we do not need
611 these ELF section. */
612 if (!in_lto_p || !flag_profile_values)
613 return get_named_text_section (decl, ".text.hot", NULL);
614 default:
615 return NULL;
619 /* Return the section for function DECL.
621 If DECL is NULL_TREE, return the text section. We can be passed
622 NULL_TREE under some circumstances by dbxout.c at least.
624 If FORCE_COLD is true, return cold function section ignoring
625 the frequency info of cgraph_node. */
627 static section *
628 function_section_1 (tree decl, bool force_cold)
630 section *section = NULL;
631 enum node_frequency freq = NODE_FREQUENCY_NORMAL;
632 bool startup = false, exit = false;
634 if (decl)
636 struct cgraph_node *node = cgraph_node::get (decl);
638 if (node)
640 freq = node->frequency;
641 startup = node->only_called_at_startup;
642 exit = node->only_called_at_exit;
645 if (force_cold)
646 freq = NODE_FREQUENCY_UNLIKELY_EXECUTED;
648 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
649 if (decl != NULL_TREE
650 && DECL_SECTION_NAME (decl) != NULL)
652 if (targetm.asm_out.function_section)
653 section = targetm.asm_out.function_section (decl, freq,
654 startup, exit);
655 if (section)
656 return section;
657 return get_named_section (decl, NULL, 0);
659 else
660 return targetm.asm_out.select_section
661 (decl, freq == NODE_FREQUENCY_UNLIKELY_EXECUTED,
662 DECL_ALIGN (decl));
663 #else
664 if (targetm.asm_out.function_section)
665 section = targetm.asm_out.function_section (decl, freq, startup, exit);
666 if (section)
667 return section;
668 return hot_function_section (decl);
669 #endif
672 /* Return the section for function DECL.
674 If DECL is NULL_TREE, return the text section. We can be passed
675 NULL_TREE under some circumstances by dbxout.c at least. */
677 section *
678 function_section (tree decl)
680 /* Handle cases where function splitting code decides
681 to put function entry point into unlikely executed section
682 despite the fact that the function itself is not cold
683 (i.e. it is called rarely but contains a hot loop that is
684 better to live in hot subsection for the code locality). */
685 return function_section_1 (decl,
686 first_function_block_is_cold);
689 /* Return the section for the current function, take IN_COLD_SECTION_P
690 into account. */
692 section *
693 current_function_section (void)
695 return function_section_1 (current_function_decl, in_cold_section_p);
698 /* Tell assembler to switch to unlikely-to-be-executed text section. */
700 section *
701 unlikely_text_section (void)
703 return function_section_1 (current_function_decl, true);
706 /* When called within a function context, return true if the function
707 has been assigned a cold text section and if SECT is that section.
708 When called outside a function context, return true if SECT is the
709 default cold section. */
711 bool
712 unlikely_text_section_p (section *sect)
714 return sect == function_section_1 (current_function_decl, true);
717 /* Return the read-only data section associated with function DECL. */
719 section *
720 default_function_rodata_section (tree decl)
722 if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
724 const char *name = DECL_SECTION_NAME (decl);
726 if (DECL_COMDAT_GROUP (decl) && HAVE_COMDAT_GROUP)
728 const char *dot;
729 size_t len;
730 char* rname;
732 dot = strchr (name + 1, '.');
733 if (!dot)
734 dot = name;
735 len = strlen (dot) + 8;
736 rname = (char *) alloca (len);
738 strcpy (rname, ".rodata");
739 strcat (rname, dot);
740 return get_section (rname, SECTION_LINKONCE, decl);
742 /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo. */
743 else if (DECL_COMDAT_GROUP (decl)
744 && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
746 size_t len = strlen (name) + 1;
747 char *rname = (char *) alloca (len);
749 memcpy (rname, name, len);
750 rname[14] = 'r';
751 return get_section (rname, SECTION_LINKONCE, decl);
753 /* For .text.foo we want to use .rodata.foo. */
754 else if (flag_function_sections && flag_data_sections
755 && strncmp (name, ".text.", 6) == 0)
757 size_t len = strlen (name) + 1;
758 char *rname = (char *) alloca (len + 2);
760 memcpy (rname, ".rodata", 7);
761 memcpy (rname + 7, name + 5, len - 5);
762 return get_section (rname, 0, decl);
766 return readonly_data_section;
769 /* Return the read-only data section associated with function DECL
770 for targets where that section should be always the single
771 readonly data section. */
773 section *
774 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
776 return readonly_data_section;
779 /* Return the section to use for string merging. */
781 static section *
782 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
783 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
784 unsigned int flags ATTRIBUTE_UNUSED)
786 HOST_WIDE_INT len;
788 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
789 && TREE_CODE (decl) == STRING_CST
790 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
791 && align <= 256
792 && (len = int_size_in_bytes (TREE_TYPE (decl))) > 0
793 && TREE_STRING_LENGTH (decl) >= len)
795 machine_mode mode;
796 unsigned int modesize;
797 const char *str;
798 HOST_WIDE_INT i;
799 int j, unit;
800 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
801 char *name = (char *) alloca (strlen (prefix) + 30);
803 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
804 modesize = GET_MODE_BITSIZE (mode);
805 if (modesize >= 8 && modesize <= 256
806 && (modesize & (modesize - 1)) == 0)
808 if (align < modesize)
809 align = modesize;
811 str = TREE_STRING_POINTER (decl);
812 unit = GET_MODE_SIZE (mode);
814 /* Check for embedded NUL characters. */
815 for (i = 0; i < len; i += unit)
817 for (j = 0; j < unit; j++)
818 if (str[i + j] != '\0')
819 break;
820 if (j == unit)
821 break;
823 if (i == len - unit)
825 sprintf (name, "%s.str%d.%d", prefix,
826 modesize / 8, (int) (align / 8));
827 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
828 return get_section (name, flags, NULL);
833 return readonly_data_section;
836 /* Return the section to use for constant merging. */
838 section *
839 mergeable_constant_section (machine_mode mode ATTRIBUTE_UNUSED,
840 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
841 unsigned int flags ATTRIBUTE_UNUSED)
843 unsigned int modesize = GET_MODE_BITSIZE (mode);
845 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
846 && mode != VOIDmode
847 && mode != BLKmode
848 && modesize <= align
849 && align >= 8
850 && align <= 256
851 && (align & (align - 1)) == 0)
853 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
854 char *name = (char *) alloca (strlen (prefix) + 30);
856 sprintf (name, "%s.cst%d", prefix, (int) (align / 8));
857 flags |= (align / 8) | SECTION_MERGE;
858 return get_section (name, flags, NULL);
860 return readonly_data_section;
863 /* Given NAME, a putative register name, discard any customary prefixes. */
865 static const char *
866 strip_reg_name (const char *name)
868 #ifdef REGISTER_PREFIX
869 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
870 name += strlen (REGISTER_PREFIX);
871 #endif
872 if (name[0] == '%' || name[0] == '#')
873 name++;
874 return name;
877 /* The user has asked for a DECL to have a particular name. Set (or
878 change) it in such a way that we don't prefix an underscore to
879 it. */
880 void
881 set_user_assembler_name (tree decl, const char *name)
883 char *starred = (char *) alloca (strlen (name) + 2);
884 starred[0] = '*';
885 strcpy (starred + 1, name);
886 symtab->change_decl_assembler_name (decl, get_identifier (starred));
887 SET_DECL_RTL (decl, NULL_RTX);
890 /* Decode an `asm' spec for a declaration as a register name.
891 Return the register number, or -1 if nothing specified,
892 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
893 or -3 if ASMSPEC is `cc' and is not recognized,
894 or -4 if ASMSPEC is `memory' and is not recognized.
895 Accept an exact spelling or a decimal number.
896 Prefixes such as % are optional. */
899 decode_reg_name_and_count (const char *asmspec, int *pnregs)
901 /* Presume just one register is clobbered. */
902 *pnregs = 1;
904 if (asmspec != 0)
906 int i;
908 /* Get rid of confusing prefixes. */
909 asmspec = strip_reg_name (asmspec);
911 /* Allow a decimal number as a "register name". */
912 for (i = strlen (asmspec) - 1; i >= 0; i--)
913 if (! ISDIGIT (asmspec[i]))
914 break;
915 if (asmspec[0] != 0 && i < 0)
917 i = atoi (asmspec);
918 if (i < FIRST_PSEUDO_REGISTER && i >= 0 && reg_names[i][0])
919 return i;
920 else
921 return -2;
924 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
925 if (reg_names[i][0]
926 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
927 return i;
929 #ifdef OVERLAPPING_REGISTER_NAMES
931 static const struct
933 const char *const name;
934 const int number;
935 const int nregs;
936 } table[] = OVERLAPPING_REGISTER_NAMES;
938 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
939 if (table[i].name[0]
940 && ! strcmp (asmspec, table[i].name))
942 *pnregs = table[i].nregs;
943 return table[i].number;
946 #endif /* OVERLAPPING_REGISTER_NAMES */
948 #ifdef ADDITIONAL_REGISTER_NAMES
950 static const struct { const char *const name; const int number; } table[]
951 = ADDITIONAL_REGISTER_NAMES;
953 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
954 if (table[i].name[0]
955 && ! strcmp (asmspec, table[i].name)
956 && reg_names[table[i].number][0])
957 return table[i].number;
959 #endif /* ADDITIONAL_REGISTER_NAMES */
961 if (!strcmp (asmspec, "memory"))
962 return -4;
964 if (!strcmp (asmspec, "cc"))
965 return -3;
967 return -2;
970 return -1;
974 decode_reg_name (const char *name)
976 int count;
977 return decode_reg_name_and_count (name, &count);
981 /* Return true if DECL's initializer is suitable for a BSS section. */
983 bool
984 bss_initializer_p (const_tree decl)
986 return (DECL_INITIAL (decl) == NULL
987 /* In LTO we have no errors in program; error_mark_node is used
988 to mark offlined constructors. */
989 || (DECL_INITIAL (decl) == error_mark_node
990 && !in_lto_p)
991 || (flag_zero_initialized_in_bss
992 /* Leave constant zeroes in .rodata so they
993 can be shared. */
994 && !TREE_READONLY (decl)
995 && initializer_zerop (DECL_INITIAL (decl))));
998 /* Compute the alignment of variable specified by DECL.
999 DONT_OUTPUT_DATA is from assemble_variable. */
1001 void
1002 align_variable (tree decl, bool dont_output_data)
1004 unsigned int align = DECL_ALIGN (decl);
1006 /* In the case for initialing an array whose length isn't specified,
1007 where we have not yet been able to do the layout,
1008 figure out the proper alignment now. */
1009 if (dont_output_data && DECL_SIZE (decl) == 0
1010 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
1011 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
1013 /* Some object file formats have a maximum alignment which they support.
1014 In particular, a.out format supports a maximum alignment of 4. */
1015 if (align > MAX_OFILE_ALIGNMENT)
1017 error ("alignment of %q+D is greater than maximum object "
1018 "file alignment %d", decl,
1019 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
1020 align = MAX_OFILE_ALIGNMENT;
1023 if (! DECL_USER_ALIGN (decl))
1025 #ifdef DATA_ABI_ALIGNMENT
1026 unsigned int data_abi_align
1027 = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1028 /* For backwards compatibility, don't assume the ABI alignment for
1029 TLS variables. */
1030 if (! DECL_THREAD_LOCAL_P (decl) || data_abi_align <= BITS_PER_WORD)
1031 align = data_abi_align;
1032 #endif
1034 /* On some machines, it is good to increase alignment sometimes.
1035 But as DECL_ALIGN is used both for actually emitting the variable
1036 and for code accessing the variable as guaranteed alignment, we
1037 can only increase the alignment if it is a performance optimization
1038 if the references to it must bind to the current definition. */
1039 if (decl_binds_to_current_def_p (decl)
1040 && !DECL_VIRTUAL_P (decl))
1042 #ifdef DATA_ALIGNMENT
1043 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1044 /* Don't increase alignment too much for TLS variables - TLS space
1045 is too precious. */
1046 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1047 align = data_align;
1048 #endif
1049 #ifdef CONSTANT_ALIGNMENT
1050 if (DECL_INITIAL (decl) != 0
1051 /* In LTO we have no errors in program; error_mark_node is used
1052 to mark offlined constructors. */
1053 && (in_lto_p || DECL_INITIAL (decl) != error_mark_node))
1055 unsigned int const_align
1056 = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
1057 /* Don't increase alignment too much for TLS variables - TLS
1058 space is too precious. */
1059 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1060 align = const_align;
1062 #endif
1066 /* Reset the alignment in case we have made it tighter, so we can benefit
1067 from it in get_pointer_alignment. */
1068 DECL_ALIGN (decl) = align;
1071 /* Return DECL_ALIGN (decl), possibly increased for optimization purposes
1072 beyond what align_variable returned. */
1074 static unsigned int
1075 get_variable_align (tree decl)
1077 unsigned int align = DECL_ALIGN (decl);
1079 /* For user aligned vars or static vars align_variable already did
1080 everything. */
1081 if (DECL_USER_ALIGN (decl) || !TREE_PUBLIC (decl))
1082 return align;
1084 #ifdef DATA_ABI_ALIGNMENT
1085 if (DECL_THREAD_LOCAL_P (decl))
1086 align = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1087 #endif
1089 /* For decls that bind to the current definition, align_variable
1090 did also everything, except for not assuming ABI required alignment
1091 of TLS variables. For other vars, increase the alignment here
1092 as an optimization. */
1093 if (!decl_binds_to_current_def_p (decl))
1095 /* On some machines, it is good to increase alignment sometimes. */
1096 #ifdef DATA_ALIGNMENT
1097 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1098 /* Don't increase alignment too much for TLS variables - TLS space
1099 is too precious. */
1100 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1101 align = data_align;
1102 #endif
1103 #ifdef CONSTANT_ALIGNMENT
1104 if (DECL_INITIAL (decl) != 0
1105 /* In LTO we have no errors in program; error_mark_node is used
1106 to mark offlined constructors. */
1107 && (in_lto_p || DECL_INITIAL (decl) != error_mark_node))
1109 unsigned int const_align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl),
1110 align);
1111 /* Don't increase alignment too much for TLS variables - TLS space
1112 is too precious. */
1113 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1114 align = const_align;
1116 #endif
1119 return align;
1122 /* Return the section into which the given VAR_DECL or CONST_DECL
1123 should be placed. PREFER_NOSWITCH_P is true if a noswitch
1124 section should be used wherever possible. */
1126 section *
1127 get_variable_section (tree decl, bool prefer_noswitch_p)
1129 addr_space_t as = ADDR_SPACE_GENERIC;
1130 int reloc;
1131 varpool_node *vnode = varpool_node::get (decl);
1132 if (vnode)
1134 vnode = vnode->ultimate_alias_target ();
1135 decl = vnode->decl;
1138 if (TREE_TYPE (decl) != error_mark_node)
1139 as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1141 /* We need the constructor to figure out reloc flag. */
1142 if (vnode)
1143 vnode->get_constructor ();
1145 if (DECL_COMMON (decl))
1147 /* If the decl has been given an explicit section name, or it resides
1148 in a non-generic address space, then it isn't common, and shouldn't
1149 be handled as such. */
1150 gcc_assert (DECL_SECTION_NAME (decl) == NULL
1151 && ADDR_SPACE_GENERIC_P (as));
1152 if (DECL_THREAD_LOCAL_P (decl))
1153 return tls_comm_section;
1154 else if (TREE_PUBLIC (decl) && bss_initializer_p (decl))
1155 return comm_section;
1158 if (DECL_INITIAL (decl) == error_mark_node)
1159 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1160 else if (DECL_INITIAL (decl))
1161 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1162 else
1163 reloc = 0;
1165 resolve_unique_section (decl, reloc, flag_data_sections);
1166 if (IN_NAMED_SECTION (decl))
1167 return get_named_section (decl, NULL, reloc);
1169 if (ADDR_SPACE_GENERIC_P (as)
1170 && !DECL_THREAD_LOCAL_P (decl)
1171 && !(prefer_noswitch_p && targetm.have_switchable_bss_sections)
1172 && bss_initializer_p (decl))
1174 if (!TREE_PUBLIC (decl)
1175 && !((flag_sanitize & SANITIZE_ADDRESS)
1176 && asan_protect_global (decl)))
1177 return lcomm_section;
1178 if (bss_noswitch_section)
1179 return bss_noswitch_section;
1182 return targetm.asm_out.select_section (decl, reloc,
1183 get_variable_align (decl));
1186 /* Return the block into which object_block DECL should be placed. */
1188 static struct object_block *
1189 get_block_for_decl (tree decl)
1191 section *sect;
1193 if (TREE_CODE (decl) == VAR_DECL)
1195 /* The object must be defined in this translation unit. */
1196 if (DECL_EXTERNAL (decl))
1197 return NULL;
1199 /* There's no point using object blocks for something that is
1200 isolated by definition. */
1201 if (DECL_COMDAT_GROUP (decl))
1202 return NULL;
1205 /* We can only calculate block offsets if the decl has a known
1206 constant size. */
1207 if (DECL_SIZE_UNIT (decl) == NULL)
1208 return NULL;
1209 if (!tree_fits_uhwi_p (DECL_SIZE_UNIT (decl)))
1210 return NULL;
1212 /* Find out which section should contain DECL. We cannot put it into
1213 an object block if it requires a standalone definition. */
1214 if (TREE_CODE (decl) == VAR_DECL)
1215 align_variable (decl, 0);
1216 sect = get_variable_section (decl, true);
1217 if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
1218 return NULL;
1220 return get_block_for_section (sect);
1223 /* Make sure block symbol SYMBOL is in block BLOCK. */
1225 static void
1226 change_symbol_block (rtx symbol, struct object_block *block)
1228 if (block != SYMBOL_REF_BLOCK (symbol))
1230 gcc_assert (SYMBOL_REF_BLOCK_OFFSET (symbol) < 0);
1231 SYMBOL_REF_BLOCK (symbol) = block;
1235 /* Return true if it is possible to put DECL in an object_block. */
1237 static bool
1238 use_blocks_for_decl_p (tree decl)
1240 struct symtab_node *snode;
1242 /* Only data DECLs can be placed into object blocks. */
1243 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != CONST_DECL)
1244 return false;
1246 /* Detect decls created by dw2_force_const_mem. Such decls are
1247 special because DECL_INITIAL doesn't specify the decl's true value.
1248 dw2_output_indirect_constants will instead call assemble_variable
1249 with dont_output_data set to 1 and then print the contents itself. */
1250 if (DECL_INITIAL (decl) == decl)
1251 return false;
1253 /* If this decl is an alias, then we don't want to emit a
1254 definition. */
1255 if (TREE_CODE (decl) == VAR_DECL
1256 && (snode = symtab_node::get (decl)) != NULL
1257 && snode->alias)
1258 return false;
1260 return targetm.use_blocks_for_decl_p (decl);
1263 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS
1264 until we find an identifier that is not itself a transparent alias.
1265 Modify the alias passed to it by reference (and all aliases on the
1266 way to the ultimate target), such that they do not have to be
1267 followed again, and return the ultimate target of the alias
1268 chain. */
1270 static inline tree
1271 ultimate_transparent_alias_target (tree *alias)
1273 tree target = *alias;
1275 if (IDENTIFIER_TRANSPARENT_ALIAS (target))
1277 gcc_assert (TREE_CHAIN (target));
1278 target = ultimate_transparent_alias_target (&TREE_CHAIN (target));
1279 gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target)
1280 && ! TREE_CHAIN (target));
1281 *alias = target;
1284 return target;
1287 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
1288 have static storage duration. In other words, it should not be an
1289 automatic variable, including PARM_DECLs.
1291 There is, however, one exception: this function handles variables
1292 explicitly placed in a particular register by the user.
1294 This is never called for PARM_DECL nodes. */
1296 void
1297 make_decl_rtl (tree decl)
1299 const char *name = 0;
1300 int reg_number;
1301 tree id;
1302 rtx x;
1304 /* Check that we are not being given an automatic variable. */
1305 gcc_assert (TREE_CODE (decl) != PARM_DECL
1306 && TREE_CODE (decl) != RESULT_DECL);
1308 /* A weak alias has TREE_PUBLIC set but not the other bits. */
1309 gcc_assert (TREE_CODE (decl) != VAR_DECL
1310 || TREE_STATIC (decl)
1311 || TREE_PUBLIC (decl)
1312 || DECL_EXTERNAL (decl)
1313 || DECL_REGISTER (decl));
1315 /* And that we were not given a type or a label. */
1316 gcc_assert (TREE_CODE (decl) != TYPE_DECL
1317 && TREE_CODE (decl) != LABEL_DECL);
1319 /* For a duplicate declaration, we can be called twice on the
1320 same DECL node. Don't discard the RTL already made. */
1321 if (DECL_RTL_SET_P (decl))
1323 /* If the old RTL had the wrong mode, fix the mode. */
1324 x = DECL_RTL (decl);
1325 if (GET_MODE (x) != DECL_MODE (decl))
1326 SET_DECL_RTL (decl, adjust_address_nv (x, DECL_MODE (decl), 0));
1328 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1329 return;
1331 /* ??? Another way to do this would be to maintain a hashed
1332 table of such critters. Instead of adding stuff to a DECL
1333 to give certain attributes to it, we could use an external
1334 hash map from DECL to set of attributes. */
1336 /* Let the target reassign the RTL if it wants.
1337 This is necessary, for example, when one machine specific
1338 decl attribute overrides another. */
1339 targetm.encode_section_info (decl, DECL_RTL (decl), false);
1341 /* If the symbol has a SYMBOL_REF_BLOCK field, update it based
1342 on the new decl information. */
1343 if (MEM_P (x)
1344 && GET_CODE (XEXP (x, 0)) == SYMBOL_REF
1345 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (x, 0)))
1346 change_symbol_block (XEXP (x, 0), get_block_for_decl (decl));
1348 return;
1351 /* If this variable belongs to the global constant pool, retrieve the
1352 pre-computed RTL or recompute it in LTO mode. */
1353 if (TREE_CODE (decl) == VAR_DECL && DECL_IN_CONSTANT_POOL (decl))
1355 SET_DECL_RTL (decl, output_constant_def (DECL_INITIAL (decl), 1));
1356 return;
1359 id = DECL_ASSEMBLER_NAME (decl);
1360 if (TREE_CODE (decl) == FUNCTION_DECL
1361 && cgraph_node::get (decl)
1362 && cgraph_node::get (decl)->instrumentation_clone)
1363 ultimate_transparent_alias_target (&id);
1364 name = IDENTIFIER_POINTER (id);
1366 if (name[0] != '*' && TREE_CODE (decl) != FUNCTION_DECL
1367 && DECL_REGISTER (decl))
1369 error ("register name not specified for %q+D", decl);
1371 else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1373 const char *asmspec = name+1;
1374 machine_mode mode = DECL_MODE (decl);
1375 reg_number = decode_reg_name (asmspec);
1376 /* First detect errors in declaring global registers. */
1377 if (reg_number == -1)
1378 error ("register name not specified for %q+D", decl);
1379 else if (reg_number < 0)
1380 error ("invalid register name for %q+D", decl);
1381 else if (mode == BLKmode)
1382 error ("data type of %q+D isn%'t suitable for a register",
1383 decl);
1384 else if (!in_hard_reg_set_p (accessible_reg_set, mode, reg_number))
1385 error ("the register specified for %q+D cannot be accessed"
1386 " by the current target", decl);
1387 else if (!in_hard_reg_set_p (operand_reg_set, mode, reg_number))
1388 error ("the register specified for %q+D is not general enough"
1389 " to be used as a register variable", decl);
1390 else if (!HARD_REGNO_MODE_OK (reg_number, mode))
1391 error ("register specified for %q+D isn%'t suitable for data type",
1392 decl);
1393 /* Now handle properly declared static register variables. */
1394 else
1396 int nregs;
1398 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
1400 DECL_INITIAL (decl) = 0;
1401 error ("global register variable has initial value");
1403 if (TREE_THIS_VOLATILE (decl))
1404 warning (OPT_Wvolatile_register_var,
1405 "optimization may eliminate reads and/or "
1406 "writes to register variables");
1408 /* If the user specified one of the eliminables registers here,
1409 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
1410 confused with that register and be eliminated. This usage is
1411 somewhat suspect... */
1413 SET_DECL_RTL (decl, gen_rtx_raw_REG (mode, reg_number));
1414 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
1415 REG_USERVAR_P (DECL_RTL (decl)) = 1;
1417 if (TREE_STATIC (decl))
1419 /* Make this register global, so not usable for anything
1420 else. */
1421 #ifdef ASM_DECLARE_REGISTER_GLOBAL
1422 name = IDENTIFIER_POINTER (DECL_NAME (decl));
1423 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
1424 #endif
1425 nregs = hard_regno_nregs[reg_number][mode];
1426 while (nregs > 0)
1427 globalize_reg (decl, reg_number + --nregs);
1430 /* As a register variable, it has no section. */
1431 return;
1433 /* Avoid internal errors from invalid register
1434 specifications. */
1435 SET_DECL_ASSEMBLER_NAME (decl, NULL_TREE);
1436 DECL_HARD_REGISTER (decl) = 0;
1437 return;
1439 /* Now handle ordinary static variables and functions (in memory).
1440 Also handle vars declared register invalidly. */
1441 else if (name[0] == '*')
1443 #ifdef REGISTER_PREFIX
1444 if (strlen (REGISTER_PREFIX) != 0)
1446 reg_number = decode_reg_name (name);
1447 if (reg_number >= 0 || reg_number == -3)
1448 error ("register name given for non-register variable %q+D", decl);
1450 #endif
1453 /* Specifying a section attribute on a variable forces it into a
1454 non-.bss section, and thus it cannot be common. */
1455 /* FIXME: In general this code should not be necessary because
1456 visibility pass is doing the same work. But notice_global_symbol
1457 is called early and it needs to make DECL_RTL to get the name.
1458 we take care of recomputing the DECL_RTL after visibility is changed. */
1459 if (TREE_CODE (decl) == VAR_DECL
1460 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl))
1461 && DECL_SECTION_NAME (decl) != NULL
1462 && DECL_INITIAL (decl) == NULL_TREE
1463 && DECL_COMMON (decl))
1464 DECL_COMMON (decl) = 0;
1466 /* Variables can't be both common and weak. */
1467 if (TREE_CODE (decl) == VAR_DECL && DECL_WEAK (decl))
1468 DECL_COMMON (decl) = 0;
1470 if (use_object_blocks_p () && use_blocks_for_decl_p (decl))
1471 x = create_block_symbol (name, get_block_for_decl (decl), -1);
1472 else
1474 machine_mode address_mode = Pmode;
1475 if (TREE_TYPE (decl) != error_mark_node)
1477 addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1478 address_mode = targetm.addr_space.address_mode (as);
1480 x = gen_rtx_SYMBOL_REF (address_mode, name);
1482 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
1483 SET_SYMBOL_REF_DECL (x, decl);
1485 x = gen_rtx_MEM (DECL_MODE (decl), x);
1486 if (TREE_CODE (decl) != FUNCTION_DECL)
1487 set_mem_attributes (x, decl, 1);
1488 SET_DECL_RTL (decl, x);
1490 /* Optionally set flags or add text to the name to record information
1491 such as that it is a function name.
1492 If the name is changed, the macro ASM_OUTPUT_LABELREF
1493 will have to know how to strip this information. */
1494 targetm.encode_section_info (decl, DECL_RTL (decl), true);
1497 /* Like make_decl_rtl, but inhibit creation of new alias sets when
1498 calling make_decl_rtl. Also, reset DECL_RTL before returning the
1499 rtl. */
1502 make_decl_rtl_for_debug (tree decl)
1504 unsigned int save_aliasing_flag;
1505 rtx rtl;
1507 if (DECL_RTL_SET_P (decl))
1508 return DECL_RTL (decl);
1510 /* Kludge alert! Somewhere down the call chain, make_decl_rtl will
1511 call new_alias_set. If running with -fcompare-debug, sometimes
1512 we do not want to create alias sets that will throw the alias
1513 numbers off in the comparison dumps. So... clearing
1514 flag_strict_aliasing will keep new_alias_set() from creating a
1515 new set. */
1516 save_aliasing_flag = flag_strict_aliasing;
1517 flag_strict_aliasing = 0;
1519 rtl = DECL_RTL (decl);
1520 /* Reset DECL_RTL back, as various parts of the compiler expects
1521 DECL_RTL set meaning it is actually going to be output. */
1522 SET_DECL_RTL (decl, NULL);
1524 flag_strict_aliasing = save_aliasing_flag;
1525 return rtl;
1528 /* Output a string of literal assembler code
1529 for an `asm' keyword used between functions. */
1531 void
1532 assemble_asm (tree string)
1534 const char *p;
1535 app_enable ();
1537 if (TREE_CODE (string) == ADDR_EXPR)
1538 string = TREE_OPERAND (string, 0);
1540 p = TREE_STRING_POINTER (string);
1541 fprintf (asm_out_file, "%s%s\n", p[0] == '\t' ? "" : "\t", p);
1544 /* Write the address of the entity given by SYMBOL to SEC. */
1545 void
1546 assemble_addr_to_section (rtx symbol, section *sec)
1548 switch_to_section (sec);
1549 assemble_align (POINTER_SIZE);
1550 assemble_integer (symbol, POINTER_SIZE_UNITS, POINTER_SIZE, 1);
1553 /* Return the numbered .ctors.N (if CONSTRUCTOR_P) or .dtors.N (if
1554 not) section for PRIORITY. */
1555 section *
1556 get_cdtor_priority_section (int priority, bool constructor_p)
1558 char buf[16];
1560 /* ??? This only works reliably with the GNU linker. */
1561 sprintf (buf, "%s.%.5u",
1562 constructor_p ? ".ctors" : ".dtors",
1563 /* Invert the numbering so the linker puts us in the proper
1564 order; constructors are run from right to left, and the
1565 linker sorts in increasing order. */
1566 MAX_INIT_PRIORITY - priority);
1567 return get_section (buf, SECTION_WRITE, NULL);
1570 void
1571 default_named_section_asm_out_destructor (rtx symbol, int priority)
1573 section *sec;
1575 if (priority != DEFAULT_INIT_PRIORITY)
1576 sec = get_cdtor_priority_section (priority,
1577 /*constructor_p=*/false);
1578 else
1579 sec = get_section (".dtors", SECTION_WRITE, NULL);
1581 assemble_addr_to_section (symbol, sec);
1584 #ifdef DTORS_SECTION_ASM_OP
1585 void
1586 default_dtor_section_asm_out_destructor (rtx symbol,
1587 int priority ATTRIBUTE_UNUSED)
1589 assemble_addr_to_section (symbol, dtors_section);
1591 #endif
1593 void
1594 default_named_section_asm_out_constructor (rtx symbol, int priority)
1596 section *sec;
1598 if (priority != DEFAULT_INIT_PRIORITY)
1599 sec = get_cdtor_priority_section (priority,
1600 /*constructor_p=*/true);
1601 else
1602 sec = get_section (".ctors", SECTION_WRITE, NULL);
1604 assemble_addr_to_section (symbol, sec);
1607 #ifdef CTORS_SECTION_ASM_OP
1608 void
1609 default_ctor_section_asm_out_constructor (rtx symbol,
1610 int priority ATTRIBUTE_UNUSED)
1612 assemble_addr_to_section (symbol, ctors_section);
1614 #endif
1616 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1617 a nonzero value if the constant pool should be output before the
1618 start of the function, or a zero value if the pool should output
1619 after the end of the function. The default is to put it before the
1620 start. */
1622 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1623 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1624 #endif
1626 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1627 to be output to assembler.
1628 Set first_global_object_name and weak_global_object_name as appropriate. */
1630 void
1631 notice_global_symbol (tree decl)
1633 const char **type = &first_global_object_name;
1635 if (first_global_object_name
1636 || !TREE_PUBLIC (decl)
1637 || DECL_EXTERNAL (decl)
1638 || !DECL_NAME (decl)
1639 || (TREE_CODE (decl) != FUNCTION_DECL
1640 && (TREE_CODE (decl) != VAR_DECL
1641 || (DECL_COMMON (decl)
1642 && (DECL_INITIAL (decl) == 0
1643 || DECL_INITIAL (decl) == error_mark_node))))
1644 || !MEM_P (DECL_RTL (decl)))
1645 return;
1647 /* We win when global object is found, but it is useful to know about weak
1648 symbol as well so we can produce nicer unique names. */
1649 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl) || flag_shlib)
1650 type = &weak_global_object_name;
1652 if (!*type)
1654 const char *p;
1655 const char *name;
1656 rtx decl_rtl = DECL_RTL (decl);
1658 p = targetm.strip_name_encoding (XSTR (XEXP (decl_rtl, 0), 0));
1659 name = ggc_strdup (p);
1661 *type = name;
1665 /* If not using flag_reorder_blocks_and_partition, decide early whether the
1666 current function goes into the cold section, so that targets can use
1667 current_function_section during RTL expansion. DECL describes the
1668 function. */
1670 void
1671 decide_function_section (tree decl)
1673 first_function_block_is_cold = false;
1675 if (flag_reorder_blocks_and_partition)
1676 /* We will decide in assemble_start_function. */
1677 return;
1679 if (DECL_SECTION_NAME (decl))
1681 struct cgraph_node *node = cgraph_node::get (current_function_decl);
1682 /* Calls to function_section rely on first_function_block_is_cold
1683 being accurate. */
1684 first_function_block_is_cold = (node
1685 && node->frequency
1686 == NODE_FREQUENCY_UNLIKELY_EXECUTED);
1689 in_cold_section_p = first_function_block_is_cold;
1692 /* Get the function's name, as described by its RTL. This may be
1693 different from the DECL_NAME name used in the source file. */
1694 const char *
1695 get_fnname_from_decl (tree decl)
1697 rtx x = DECL_RTL (decl);
1698 gcc_assert (MEM_P (x));
1699 x = XEXP (x, 0);
1700 gcc_assert (GET_CODE (x) == SYMBOL_REF);
1701 return XSTR (x, 0);
1704 /* Output assembler code for the constant pool of a function and associated
1705 with defining the name of the function. DECL describes the function.
1706 NAME is the function's name. For the constant pool, we use the current
1707 constant pool data. */
1709 void
1710 assemble_start_function (tree decl, const char *fnname)
1712 int align;
1713 char tmp_label[100];
1714 bool hot_label_written = false;
1716 if (flag_reorder_blocks_and_partition)
1718 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTB", const_labelno);
1719 crtl->subsections.hot_section_label = ggc_strdup (tmp_label);
1720 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDB", const_labelno);
1721 crtl->subsections.cold_section_label = ggc_strdup (tmp_label);
1722 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTE", const_labelno);
1723 crtl->subsections.hot_section_end_label = ggc_strdup (tmp_label);
1724 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDE", const_labelno);
1725 crtl->subsections.cold_section_end_label = ggc_strdup (tmp_label);
1726 const_labelno++;
1728 else
1730 crtl->subsections.hot_section_label = NULL;
1731 crtl->subsections.cold_section_label = NULL;
1732 crtl->subsections.hot_section_end_label = NULL;
1733 crtl->subsections.cold_section_end_label = NULL;
1736 /* The following code does not need preprocessing in the assembler. */
1738 app_disable ();
1740 if (CONSTANT_POOL_BEFORE_FUNCTION)
1741 output_constant_pool (fnname, decl);
1743 /* Make sure the not and cold text (code) sections are properly
1744 aligned. This is necessary here in the case where the function
1745 has both hot and cold sections, because we don't want to re-set
1746 the alignment when the section switch happens mid-function. */
1748 if (flag_reorder_blocks_and_partition)
1750 first_function_block_is_cold = false;
1752 switch_to_section (unlikely_text_section ());
1753 assemble_align (DECL_ALIGN (decl));
1754 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_label);
1756 /* When the function starts with a cold section, we need to explicitly
1757 align the hot section and write out the hot section label.
1758 But if the current function is a thunk, we do not have a CFG. */
1759 if (!cfun->is_thunk
1760 && BB_PARTITION (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) == BB_COLD_PARTITION)
1762 switch_to_section (text_section);
1763 assemble_align (DECL_ALIGN (decl));
1764 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1765 hot_label_written = true;
1766 first_function_block_is_cold = true;
1768 in_cold_section_p = first_function_block_is_cold;
1772 /* Switch to the correct text section for the start of the function. */
1774 switch_to_section (function_section (decl));
1775 if (flag_reorder_blocks_and_partition
1776 && !hot_label_written)
1777 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1779 /* Tell assembler to move to target machine's alignment for functions. */
1780 align = floor_log2 (DECL_ALIGN (decl) / BITS_PER_UNIT);
1781 if (align > 0)
1783 ASM_OUTPUT_ALIGN (asm_out_file, align);
1786 /* Handle a user-specified function alignment.
1787 Note that we still need to align to DECL_ALIGN, as above,
1788 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1789 if (! DECL_USER_ALIGN (decl)
1790 && align_functions_log > align
1791 && optimize_function_for_speed_p (cfun))
1793 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1794 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1795 align_functions_log, align_functions - 1);
1796 #else
1797 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1798 #endif
1801 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1802 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1803 #endif
1805 if (!DECL_IGNORED_P (decl))
1806 (*debug_hooks->begin_function) (decl);
1808 /* Make function name accessible from other files, if appropriate. */
1810 if (TREE_PUBLIC (decl)
1811 || (cgraph_node::get (decl)->instrumentation_clone
1812 && cgraph_node::get (decl)->instrumented_version
1813 && TREE_PUBLIC (cgraph_node::get (decl)->instrumented_version->decl)))
1815 notice_global_symbol (decl);
1817 globalize_decl (decl);
1819 maybe_assemble_visibility (decl);
1822 if (DECL_PRESERVE_P (decl))
1823 targetm.asm_out.mark_decl_preserved (fnname);
1825 /* Do any machine/system dependent processing of the function name. */
1826 #ifdef ASM_DECLARE_FUNCTION_NAME
1827 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1828 #else
1829 /* Standard thing is just output label for the function. */
1830 ASM_OUTPUT_FUNCTION_LABEL (asm_out_file, fnname, current_function_decl);
1831 #endif /* ASM_DECLARE_FUNCTION_NAME */
1833 if (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (decl)))
1834 saw_no_split_stack = true;
1837 /* Output assembler code associated with defining the size of the
1838 function. DECL describes the function. NAME is the function's name. */
1840 void
1841 assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED)
1843 #ifdef ASM_DECLARE_FUNCTION_SIZE
1844 /* We could have switched section in the middle of the function. */
1845 if (flag_reorder_blocks_and_partition)
1846 switch_to_section (function_section (decl));
1847 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1848 #endif
1849 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1851 output_constant_pool (fnname, decl);
1852 switch_to_section (function_section (decl)); /* need to switch back */
1854 /* Output labels for end of hot/cold text sections (to be used by
1855 debug info.) */
1856 if (flag_reorder_blocks_and_partition)
1858 section *save_text_section;
1860 save_text_section = in_section;
1861 switch_to_section (unlikely_text_section ());
1862 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label);
1863 if (first_function_block_is_cold)
1864 switch_to_section (text_section);
1865 else
1866 switch_to_section (function_section (decl));
1867 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label);
1868 switch_to_section (save_text_section);
1872 /* Assemble code to leave SIZE bytes of zeros. */
1874 void
1875 assemble_zeros (unsigned HOST_WIDE_INT size)
1877 /* Do no output if -fsyntax-only. */
1878 if (flag_syntax_only)
1879 return;
1881 #ifdef ASM_NO_SKIP_IN_TEXT
1882 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1883 so we must output 0s explicitly in the text section. */
1884 if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0)
1886 unsigned HOST_WIDE_INT i;
1887 for (i = 0; i < size; i++)
1888 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1890 else
1891 #endif
1892 if (size > 0)
1893 ASM_OUTPUT_SKIP (asm_out_file, size);
1896 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1898 void
1899 assemble_align (int align)
1901 if (align > BITS_PER_UNIT)
1903 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1907 /* Assemble a string constant with the specified C string as contents. */
1909 void
1910 assemble_string (const char *p, int size)
1912 int pos = 0;
1913 int maximum = 2000;
1915 /* If the string is very long, split it up. */
1917 while (pos < size)
1919 int thissize = size - pos;
1920 if (thissize > maximum)
1921 thissize = maximum;
1923 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1925 pos += thissize;
1926 p += thissize;
1931 /* A noswitch_section_callback for lcomm_section. */
1933 static bool
1934 emit_local (tree decl ATTRIBUTE_UNUSED,
1935 const char *name ATTRIBUTE_UNUSED,
1936 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1937 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1939 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1940 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name,
1941 size, DECL_ALIGN (decl));
1942 return true;
1943 #elif defined ASM_OUTPUT_ALIGNED_LOCAL
1944 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, DECL_ALIGN (decl));
1945 return true;
1946 #else
1947 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1948 return false;
1949 #endif
1952 /* A noswitch_section_callback for bss_noswitch_section. */
1954 #if defined ASM_OUTPUT_ALIGNED_BSS
1955 static bool
1956 emit_bss (tree decl ATTRIBUTE_UNUSED,
1957 const char *name ATTRIBUTE_UNUSED,
1958 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1959 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1961 #if defined ASM_OUTPUT_ALIGNED_BSS
1962 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size,
1963 get_variable_align (decl));
1964 return true;
1965 #endif
1967 #endif
1969 /* A noswitch_section_callback for comm_section. */
1971 static bool
1972 emit_common (tree decl ATTRIBUTE_UNUSED,
1973 const char *name ATTRIBUTE_UNUSED,
1974 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1975 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1977 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1978 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name,
1979 size, get_variable_align (decl));
1980 return true;
1981 #elif defined ASM_OUTPUT_ALIGNED_COMMON
1982 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size,
1983 get_variable_align (decl));
1984 return true;
1985 #else
1986 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
1987 return false;
1988 #endif
1991 /* A noswitch_section_callback for tls_comm_section. */
1993 static bool
1994 emit_tls_common (tree decl ATTRIBUTE_UNUSED,
1995 const char *name ATTRIBUTE_UNUSED,
1996 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1997 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1999 #ifdef ASM_OUTPUT_TLS_COMMON
2000 ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size);
2001 return true;
2002 #else
2003 sorry ("thread-local COMMON data not implemented");
2004 return true;
2005 #endif
2008 /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT.
2009 NAME is the name of DECL's SYMBOL_REF. */
2011 static void
2012 assemble_noswitch_variable (tree decl, const char *name, section *sect,
2013 unsigned int align)
2015 unsigned HOST_WIDE_INT size, rounded;
2017 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2018 rounded = size;
2020 if ((flag_sanitize & SANITIZE_ADDRESS) && asan_protect_global (decl))
2021 size += asan_red_zone_size (size);
2023 /* Don't allocate zero bytes of common,
2024 since that means "undefined external" in the linker. */
2025 if (size == 0)
2026 rounded = 1;
2028 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2029 so that each uninitialized object starts on such a boundary. */
2030 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
2031 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2032 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2034 if (!sect->noswitch.callback (decl, name, size, rounded)
2035 && (unsigned HOST_WIDE_INT) (align / BITS_PER_UNIT) > rounded)
2036 error ("requested alignment for %q+D is greater than "
2037 "implemented alignment of %wu", decl, rounded);
2040 /* A subroutine of assemble_variable. Output the label and contents of
2041 DECL, whose address is a SYMBOL_REF with name NAME. DONT_OUTPUT_DATA
2042 is as for assemble_variable. */
2044 static void
2045 assemble_variable_contents (tree decl, const char *name,
2046 bool dont_output_data)
2048 /* Do any machine/system dependent processing of the object. */
2049 #ifdef ASM_DECLARE_OBJECT_NAME
2050 last_assemble_variable_decl = decl;
2051 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
2052 #else
2053 /* Standard thing is just output label for the object. */
2054 ASM_OUTPUT_LABEL (asm_out_file, name);
2055 #endif /* ASM_DECLARE_OBJECT_NAME */
2057 if (!dont_output_data)
2059 /* Caller is supposed to use varpool_get_constructor when it wants
2060 to output the body. */
2061 gcc_assert (!in_lto_p || DECL_INITIAL (decl) != error_mark_node);
2062 if (DECL_INITIAL (decl)
2063 && DECL_INITIAL (decl) != error_mark_node
2064 && !initializer_zerop (DECL_INITIAL (decl)))
2065 /* Output the actual data. */
2066 output_constant (DECL_INITIAL (decl),
2067 tree_to_uhwi (DECL_SIZE_UNIT (decl)),
2068 get_variable_align (decl));
2069 else
2070 /* Leave space for it. */
2071 assemble_zeros (tree_to_uhwi (DECL_SIZE_UNIT (decl)));
2072 targetm.asm_out.decl_end ();
2076 /* Write out assembly for the variable DECL, which is not defined in
2077 the current translation unit. */
2078 void
2079 assemble_undefined_decl (tree decl)
2081 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
2082 targetm.asm_out.assemble_undefined_decl (asm_out_file, name, decl);
2085 /* Assemble everything that is needed for a variable or function declaration.
2086 Not used for automatic variables, and not used for function definitions.
2087 Should not be called for variables of incomplete structure type.
2089 TOP_LEVEL is nonzero if this variable has file scope.
2090 AT_END is nonzero if this is the special handling, at end of compilation,
2091 to define things that have had only tentative definitions.
2092 DONT_OUTPUT_DATA if nonzero means don't actually output the
2093 initial value (that will be done by the caller). */
2095 void
2096 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
2097 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
2099 const char *name;
2100 rtx decl_rtl, symbol;
2101 section *sect;
2102 unsigned int align;
2103 bool asan_protected = false;
2105 /* This function is supposed to handle VARIABLES. Ensure we have one. */
2106 gcc_assert (TREE_CODE (decl) == VAR_DECL);
2108 /* Emulated TLS had better not get this far. */
2109 gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl));
2111 last_assemble_variable_decl = 0;
2113 /* Normally no need to say anything here for external references,
2114 since assemble_external is called by the language-specific code
2115 when a declaration is first seen. */
2117 if (DECL_EXTERNAL (decl))
2118 return;
2120 /* Do nothing for global register variables. */
2121 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
2123 TREE_ASM_WRITTEN (decl) = 1;
2124 return;
2127 /* If type was incomplete when the variable was declared,
2128 see if it is complete now. */
2130 if (DECL_SIZE (decl) == 0)
2131 layout_decl (decl, 0);
2133 /* Still incomplete => don't allocate it; treat the tentative defn
2134 (which is what it must have been) as an `extern' reference. */
2136 if (!dont_output_data && DECL_SIZE (decl) == 0)
2138 error ("storage size of %q+D isn%'t known", decl);
2139 TREE_ASM_WRITTEN (decl) = 1;
2140 return;
2143 /* The first declaration of a variable that comes through this function
2144 decides whether it is global (in C, has external linkage)
2145 or local (in C, has internal linkage). So do nothing more
2146 if this function has already run. */
2148 if (TREE_ASM_WRITTEN (decl))
2149 return;
2151 /* Make sure targetm.encode_section_info is invoked before we set
2152 ASM_WRITTEN. */
2153 decl_rtl = DECL_RTL (decl);
2155 TREE_ASM_WRITTEN (decl) = 1;
2157 /* Do no output if -fsyntax-only. */
2158 if (flag_syntax_only)
2159 return;
2161 if (! dont_output_data
2162 && ! valid_constant_size_p (DECL_SIZE_UNIT (decl)))
2164 error ("size of variable %q+D is too large", decl);
2165 return;
2168 gcc_assert (MEM_P (decl_rtl));
2169 gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF);
2170 symbol = XEXP (decl_rtl, 0);
2172 /* If this symbol belongs to the tree constant pool, output the constant
2173 if it hasn't already been written. */
2174 if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
2176 tree decl = SYMBOL_REF_DECL (symbol);
2177 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
2178 output_constant_def_contents (symbol);
2179 return;
2182 app_disable ();
2184 name = XSTR (symbol, 0);
2185 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
2186 notice_global_symbol (decl);
2188 /* Compute the alignment of this data. */
2190 align_variable (decl, dont_output_data);
2192 if ((flag_sanitize & SANITIZE_ADDRESS)
2193 && asan_protect_global (decl))
2195 asan_protected = true;
2196 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
2197 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
2200 set_mem_align (decl_rtl, DECL_ALIGN (decl));
2202 align = get_variable_align (decl);
2204 if (TREE_PUBLIC (decl))
2205 maybe_assemble_visibility (decl);
2207 if (DECL_PRESERVE_P (decl))
2208 targetm.asm_out.mark_decl_preserved (name);
2210 /* First make the assembler name(s) global if appropriate. */
2211 sect = get_variable_section (decl, false);
2212 if (TREE_PUBLIC (decl)
2213 && (sect->common.flags & SECTION_COMMON) == 0)
2214 globalize_decl (decl);
2216 /* Output any data that we will need to use the address of. */
2217 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
2218 output_addressed_constants (DECL_INITIAL (decl));
2220 /* dbxout.c needs to know this. */
2221 if (sect && (sect->common.flags & SECTION_CODE) != 0)
2222 DECL_IN_TEXT_SECTION (decl) = 1;
2224 /* If the decl is part of an object_block, make sure that the decl
2225 has been positioned within its block, but do not write out its
2226 definition yet. output_object_blocks will do that later. */
2227 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
2229 gcc_assert (!dont_output_data);
2230 place_block_symbol (symbol);
2232 else if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
2233 assemble_noswitch_variable (decl, name, sect, align);
2234 else
2236 /* The following bit of code ensures that vtable_map
2237 variables are not only in the comdat section, but that
2238 each variable has its own unique comdat name. If this
2239 code is removed, the variables end up in the same section
2240 with a single comdat name.
2242 FIXME: resolve_unique_section needs to deal better with
2243 decls with both DECL_SECTION_NAME and DECL_ONE_ONLY. Once
2244 that is fixed, this if-else statement can be replaced with
2245 a single call to "switch_to_section (sect)". */
2246 if (sect->named.name
2247 && (strcmp (sect->named.name, ".vtable_map_vars") == 0))
2249 #if defined (OBJECT_FORMAT_ELF)
2250 targetm.asm_out.named_section (sect->named.name,
2251 sect->named.common.flags
2252 | SECTION_LINKONCE,
2253 DECL_NAME (decl));
2254 in_section = sect;
2255 #else
2256 switch_to_section (sect);
2257 #endif
2259 else
2260 switch_to_section (sect);
2261 if (align > BITS_PER_UNIT)
2262 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2263 assemble_variable_contents (decl, name, dont_output_data);
2264 if (asan_protected)
2266 unsigned HOST_WIDE_INT int size
2267 = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2268 assemble_zeros (asan_red_zone_size (size));
2274 /* Given a function declaration (FN_DECL), this function assembles the
2275 function into the .preinit_array section. */
2277 void
2278 assemble_vtv_preinit_initializer (tree fn_decl)
2280 section *sect;
2281 unsigned flags = SECTION_WRITE;
2282 rtx symbol = XEXP (DECL_RTL (fn_decl), 0);
2284 flags |= SECTION_NOTYPE;
2285 sect = get_section (".preinit_array", flags, fn_decl);
2286 switch_to_section (sect);
2287 assemble_addr_to_section (symbol, sect);
2290 /* Return 1 if type TYPE contains any pointers. */
2292 static int
2293 contains_pointers_p (tree type)
2295 switch (TREE_CODE (type))
2297 case POINTER_TYPE:
2298 case REFERENCE_TYPE:
2299 /* I'm not sure whether OFFSET_TYPE needs this treatment,
2300 so I'll play safe and return 1. */
2301 case OFFSET_TYPE:
2302 return 1;
2304 case RECORD_TYPE:
2305 case UNION_TYPE:
2306 case QUAL_UNION_TYPE:
2308 tree fields;
2309 /* For a type that has fields, see if the fields have pointers. */
2310 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2311 if (TREE_CODE (fields) == FIELD_DECL
2312 && contains_pointers_p (TREE_TYPE (fields)))
2313 return 1;
2314 return 0;
2317 case ARRAY_TYPE:
2318 /* An array type contains pointers if its element type does. */
2319 return contains_pointers_p (TREE_TYPE (type));
2321 default:
2322 return 0;
2326 /* We delay assemble_external processing until
2327 the compilation unit is finalized. This is the best we can do for
2328 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2329 it all the way to final. See PR 17982 for further discussion. */
2330 static GTY(()) tree pending_assemble_externals;
2332 #ifdef ASM_OUTPUT_EXTERNAL
2333 /* Some targets delay some output to final using TARGET_ASM_FILE_END.
2334 As a result, assemble_external can be called after the list of externals
2335 is processed and the pointer set destroyed. */
2336 static bool pending_assemble_externals_processed;
2338 /* Avoid O(external_decls**2) lookups in the pending_assemble_externals
2339 TREE_LIST in assemble_external. */
2340 static hash_set<tree> *pending_assemble_externals_set;
2342 /* True if DECL is a function decl for which no out-of-line copy exists.
2343 It is assumed that DECL's assembler name has been set. */
2345 static bool
2346 incorporeal_function_p (tree decl)
2348 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
2350 const char *name;
2352 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2353 && (DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA
2354 || DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA_WITH_ALIGN))
2355 return true;
2357 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2358 /* Atomic or sync builtins which have survived this far will be
2359 resolved externally and therefore are not incorporeal. */
2360 if (strncmp (name, "__builtin_", 10) == 0)
2361 return true;
2363 return false;
2366 /* Actually do the tests to determine if this is necessary, and invoke
2367 ASM_OUTPUT_EXTERNAL. */
2368 static void
2369 assemble_external_real (tree decl)
2371 rtx rtl = DECL_RTL (decl);
2373 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2374 && !SYMBOL_REF_USED (XEXP (rtl, 0))
2375 && !incorporeal_function_p (decl))
2377 /* Some systems do require some output. */
2378 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2379 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2382 #endif
2384 void
2385 process_pending_assemble_externals (void)
2387 #ifdef ASM_OUTPUT_EXTERNAL
2388 tree list;
2389 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2390 assemble_external_real (TREE_VALUE (list));
2392 pending_assemble_externals = 0;
2393 pending_assemble_externals_processed = true;
2394 delete pending_assemble_externals_set;
2395 #endif
2398 /* This TREE_LIST contains any weak symbol declarations waiting
2399 to be emitted. */
2400 static GTY(()) tree weak_decls;
2402 /* Output something to declare an external symbol to the assembler,
2403 and qualifiers such as weakness. (Most assemblers don't need
2404 extern declaration, so we normally output nothing.) Do nothing if
2405 DECL is not external. */
2407 void
2408 assemble_external (tree decl ATTRIBUTE_UNUSED)
2410 /* Make sure that the ASM_OUT_FILE is open.
2411 If it's not, we should not be calling this function. */
2412 gcc_assert (asm_out_file);
2414 /* In a perfect world, the following condition would be true.
2415 Sadly, the Java and Go front ends emit assembly *from the front end*,
2416 bypassing the call graph. See PR52739. Fix before GCC 4.8. */
2417 #if 0
2418 /* This function should only be called if we are expanding, or have
2419 expanded, to RTL.
2420 Ideally, only final.c would be calling this function, but it is
2421 not clear whether that would break things somehow. See PR 17982
2422 for further discussion. */
2423 gcc_assert (state == EXPANSION
2424 || state == FINISHED);
2425 #endif
2427 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2428 return;
2430 /* We want to output annotation for weak and external symbols at
2431 very last to check if they are references or not. */
2433 if (TARGET_SUPPORTS_WEAK
2434 && DECL_WEAK (decl)
2435 /* TREE_STATIC is a weird and abused creature which is not
2436 generally the right test for whether an entity has been
2437 locally emitted, inlined or otherwise not-really-extern, but
2438 for declarations that can be weak, it happens to be
2439 match. */
2440 && !TREE_STATIC (decl)
2441 && lookup_attribute ("weak", DECL_ATTRIBUTES (decl))
2442 && value_member (decl, weak_decls) == NULL_TREE)
2443 weak_decls = tree_cons (NULL, decl, weak_decls);
2445 #ifdef ASM_OUTPUT_EXTERNAL
2446 if (pending_assemble_externals_processed)
2448 assemble_external_real (decl);
2449 return;
2452 if (! pending_assemble_externals_set->add (decl))
2453 pending_assemble_externals = tree_cons (NULL, decl,
2454 pending_assemble_externals);
2455 #endif
2458 /* Similar, for calling a library function FUN. */
2460 void
2461 assemble_external_libcall (rtx fun)
2463 /* Declare library function name external when first used, if nec. */
2464 if (! SYMBOL_REF_USED (fun))
2466 SYMBOL_REF_USED (fun) = 1;
2467 targetm.asm_out.external_libcall (fun);
2471 /* Assemble a label named NAME. */
2473 void
2474 assemble_label (FILE *file, const char *name)
2476 ASM_OUTPUT_LABEL (file, name);
2479 /* Set the symbol_referenced flag for ID. */
2480 void
2481 mark_referenced (tree id)
2483 TREE_SYMBOL_REFERENCED (id) = 1;
2486 /* Set the symbol_referenced flag for DECL and notify callgraph. */
2487 void
2488 mark_decl_referenced (tree decl)
2490 if (TREE_CODE (decl) == FUNCTION_DECL)
2492 /* Extern inline functions don't become needed when referenced.
2493 If we know a method will be emitted in other TU and no new
2494 functions can be marked reachable, just use the external
2495 definition. */
2496 struct cgraph_node *node = cgraph_node::get_create (decl);
2497 if (!DECL_EXTERNAL (decl)
2498 && !node->definition)
2499 node->mark_force_output ();
2501 else if (TREE_CODE (decl) == VAR_DECL)
2503 varpool_node *node = varpool_node::get_create (decl);
2504 /* C++ frontend use mark_decl_references to force COMDAT variables
2505 to be output that might appear dead otherwise. */
2506 node->force_output = true;
2508 /* else do nothing - we can get various sorts of CST nodes here,
2509 which do not need to be marked. */
2513 /* Output to FILE (an assembly file) a reference to NAME. If NAME
2514 starts with a *, the rest of NAME is output verbatim. Otherwise
2515 NAME is transformed in a target-specific way (usually by the
2516 addition of an underscore). */
2518 void
2519 assemble_name_raw (FILE *file, const char *name)
2521 if (name[0] == '*')
2522 fputs (&name[1], file);
2523 else
2524 ASM_OUTPUT_LABELREF (file, name);
2527 /* Like assemble_name_raw, but should be used when NAME might refer to
2528 an entity that is also represented as a tree (like a function or
2529 variable). If NAME does refer to such an entity, that entity will
2530 be marked as referenced. */
2532 void
2533 assemble_name (FILE *file, const char *name)
2535 const char *real_name;
2536 tree id;
2538 real_name = targetm.strip_name_encoding (name);
2540 id = maybe_get_identifier (real_name);
2541 if (id)
2543 tree id_orig = id;
2545 mark_referenced (id);
2546 ultimate_transparent_alias_target (&id);
2547 if (id != id_orig)
2548 name = IDENTIFIER_POINTER (id);
2549 gcc_assert (! TREE_CHAIN (id));
2552 assemble_name_raw (file, name);
2555 /* Allocate SIZE bytes writable static space with a gensym name
2556 and return an RTX to refer to its address. */
2559 assemble_static_space (unsigned HOST_WIDE_INT size)
2561 char name[12];
2562 const char *namestring;
2563 rtx x;
2565 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2566 ++const_labelno;
2567 namestring = ggc_strdup (name);
2569 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2570 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2572 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2573 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2574 BIGGEST_ALIGNMENT);
2575 #else
2576 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2577 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2578 #else
2580 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2581 so that each uninitialized object starts on such a boundary. */
2582 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2583 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2584 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2585 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2586 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2587 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2589 #endif
2590 #endif
2591 return x;
2594 /* Assemble the static constant template for function entry trampolines.
2595 This is done at most once per compilation.
2596 Returns an RTX for the address of the template. */
2598 static GTY(()) rtx initial_trampoline;
2601 assemble_trampoline_template (void)
2603 char label[256];
2604 const char *name;
2605 int align;
2606 rtx symbol;
2608 gcc_assert (targetm.asm_out.trampoline_template != NULL);
2610 if (initial_trampoline)
2611 return initial_trampoline;
2613 /* By default, put trampoline templates in read-only data section. */
2615 #ifdef TRAMPOLINE_SECTION
2616 switch_to_section (TRAMPOLINE_SECTION);
2617 #else
2618 switch_to_section (readonly_data_section);
2619 #endif
2621 /* Write the assembler code to define one. */
2622 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2623 if (align > 0)
2624 ASM_OUTPUT_ALIGN (asm_out_file, align);
2626 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2627 targetm.asm_out.trampoline_template (asm_out_file);
2629 /* Record the rtl to refer to it. */
2630 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2631 name = ggc_strdup (label);
2632 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2633 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2635 initial_trampoline = gen_const_mem (BLKmode, symbol);
2636 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2637 set_mem_size (initial_trampoline, TRAMPOLINE_SIZE);
2639 return initial_trampoline;
2642 /* A and B are either alignments or offsets. Return the minimum alignment
2643 that may be assumed after adding the two together. */
2645 static inline unsigned
2646 min_align (unsigned int a, unsigned int b)
2648 return (a | b) & -(a | b);
2651 /* Return the assembler directive for creating a given kind of integer
2652 object. SIZE is the number of bytes in the object and ALIGNED_P
2653 indicates whether it is known to be aligned. Return NULL if the
2654 assembly dialect has no such directive.
2656 The returned string should be printed at the start of a new line and
2657 be followed immediately by the object's initial value. */
2659 const char *
2660 integer_asm_op (int size, int aligned_p)
2662 struct asm_int_op *ops;
2664 if (aligned_p)
2665 ops = &targetm.asm_out.aligned_op;
2666 else
2667 ops = &targetm.asm_out.unaligned_op;
2669 switch (size)
2671 case 1:
2672 return targetm.asm_out.byte_op;
2673 case 2:
2674 return ops->hi;
2675 case 4:
2676 return ops->si;
2677 case 8:
2678 return ops->di;
2679 case 16:
2680 return ops->ti;
2681 default:
2682 return NULL;
2686 /* Use directive OP to assemble an integer object X. Print OP at the
2687 start of the line, followed immediately by the value of X. */
2689 void
2690 assemble_integer_with_op (const char *op, rtx x)
2692 fputs (op, asm_out_file);
2693 output_addr_const (asm_out_file, x);
2694 fputc ('\n', asm_out_file);
2697 /* The default implementation of the asm_out.integer target hook. */
2699 bool
2700 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2701 unsigned int size ATTRIBUTE_UNUSED,
2702 int aligned_p ATTRIBUTE_UNUSED)
2704 const char *op = integer_asm_op (size, aligned_p);
2705 /* Avoid GAS bugs for large values. Specifically negative values whose
2706 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2707 if (size > UNITS_PER_WORD && size > POINTER_SIZE_UNITS)
2708 return false;
2709 return op && (assemble_integer_with_op (op, x), true);
2712 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2713 the alignment of the integer in bits. Return 1 if we were able to output
2714 the constant, otherwise 0. We must be able to output the constant,
2715 if FORCE is nonzero. */
2717 bool
2718 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2720 int aligned_p;
2722 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2724 /* See if the target hook can handle this kind of object. */
2725 if (targetm.asm_out.integer (x, size, aligned_p))
2726 return true;
2728 /* If the object is a multi-byte one, try splitting it up. Split
2729 it into words it if is multi-word, otherwise split it into bytes. */
2730 if (size > 1)
2732 machine_mode omode, imode;
2733 unsigned int subalign;
2734 unsigned int subsize, i;
2735 enum mode_class mclass;
2737 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2738 subalign = MIN (align, subsize * BITS_PER_UNIT);
2739 if (GET_CODE (x) == CONST_FIXED)
2740 mclass = GET_MODE_CLASS (GET_MODE (x));
2741 else
2742 mclass = MODE_INT;
2744 omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0);
2745 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0);
2747 for (i = 0; i < size; i += subsize)
2749 rtx partial = simplify_subreg (omode, x, imode, i);
2750 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2751 break;
2753 if (i == size)
2754 return true;
2756 /* If we've printed some of it, but not all of it, there's no going
2757 back now. */
2758 gcc_assert (!i);
2761 gcc_assert (!force);
2763 return false;
2766 void
2767 assemble_real (REAL_VALUE_TYPE d, machine_mode mode, unsigned int align)
2769 long data[4] = {0, 0, 0, 0};
2770 int i;
2771 int bitsize, nelts, nunits, units_per;
2773 /* This is hairy. We have a quantity of known size. real_to_target
2774 will put it into an array of *host* longs, 32 bits per element
2775 (even if long is more than 32 bits). We need to determine the
2776 number of array elements that are occupied (nelts) and the number
2777 of *target* min-addressable units that will be occupied in the
2778 object file (nunits). We cannot assume that 32 divides the
2779 mode's bitsize (size * BITS_PER_UNIT) evenly.
2781 size * BITS_PER_UNIT is used here to make sure that padding bits
2782 (which might appear at either end of the value; real_to_target
2783 will include the padding bits in its output array) are included. */
2785 nunits = GET_MODE_SIZE (mode);
2786 bitsize = nunits * BITS_PER_UNIT;
2787 nelts = CEIL (bitsize, 32);
2788 units_per = 32 / BITS_PER_UNIT;
2790 real_to_target (data, &d, mode);
2792 /* Put out the first word with the specified alignment. */
2793 assemble_integer (GEN_INT (data[0]), MIN (nunits, units_per), align, 1);
2794 nunits -= units_per;
2796 /* Subsequent words need only 32-bit alignment. */
2797 align = min_align (align, 32);
2799 for (i = 1; i < nelts; i++)
2801 assemble_integer (GEN_INT (data[i]), MIN (nunits, units_per), align, 1);
2802 nunits -= units_per;
2806 /* Given an expression EXP with a constant value,
2807 reduce it to the sum of an assembler symbol and an integer.
2808 Store them both in the structure *VALUE.
2809 EXP must be reducible. */
2811 struct addr_const {
2812 rtx base;
2813 HOST_WIDE_INT offset;
2816 static void
2817 decode_addr_const (tree exp, struct addr_const *value)
2819 tree target = TREE_OPERAND (exp, 0);
2820 int offset = 0;
2821 rtx x;
2823 while (1)
2825 if (TREE_CODE (target) == COMPONENT_REF
2826 && tree_fits_shwi_p (byte_position (TREE_OPERAND (target, 1))))
2828 offset += int_byte_position (TREE_OPERAND (target, 1));
2829 target = TREE_OPERAND (target, 0);
2831 else if (TREE_CODE (target) == ARRAY_REF
2832 || TREE_CODE (target) == ARRAY_RANGE_REF)
2834 offset += (tree_to_uhwi (TYPE_SIZE_UNIT (TREE_TYPE (target)))
2835 * tree_to_shwi (TREE_OPERAND (target, 1)));
2836 target = TREE_OPERAND (target, 0);
2838 else if (TREE_CODE (target) == MEM_REF
2839 && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR)
2841 offset += mem_ref_offset (target).to_short_addr ();
2842 target = TREE_OPERAND (TREE_OPERAND (target, 0), 0);
2844 else if (TREE_CODE (target) == INDIRECT_REF
2845 && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR
2846 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0))
2847 == ADDR_EXPR)
2848 target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0);
2849 else
2850 break;
2853 switch (TREE_CODE (target))
2855 case VAR_DECL:
2856 case FUNCTION_DECL:
2857 x = DECL_RTL (target);
2858 break;
2860 case LABEL_DECL:
2861 x = gen_rtx_MEM (FUNCTION_MODE,
2862 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2863 break;
2865 case REAL_CST:
2866 case FIXED_CST:
2867 case STRING_CST:
2868 case COMPLEX_CST:
2869 case CONSTRUCTOR:
2870 case INTEGER_CST:
2871 x = output_constant_def (target, 1);
2872 break;
2874 default:
2875 gcc_unreachable ();
2878 gcc_assert (MEM_P (x));
2879 x = XEXP (x, 0);
2881 value->base = x;
2882 value->offset = offset;
2885 static GTY(()) hash_table<tree_descriptor_hasher> *const_desc_htab;
2887 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2889 /* Constant pool accessor function. */
2891 hash_table<tree_descriptor_hasher> *
2892 constant_pool_htab (void)
2894 return const_desc_htab;
2897 /* Compute a hash code for a constant expression. */
2899 hashval_t
2900 tree_descriptor_hasher::hash (constant_descriptor_tree *ptr)
2902 return ptr->hash;
2905 static hashval_t
2906 const_hash_1 (const tree exp)
2908 const char *p;
2909 hashval_t hi;
2910 int len, i;
2911 enum tree_code code = TREE_CODE (exp);
2913 /* Either set P and LEN to the address and len of something to hash and
2914 exit the switch or return a value. */
2916 switch (code)
2918 case INTEGER_CST:
2919 p = (char *) &TREE_INT_CST_ELT (exp, 0);
2920 len = TREE_INT_CST_NUNITS (exp) * sizeof (HOST_WIDE_INT);
2921 break;
2923 case REAL_CST:
2924 return real_hash (TREE_REAL_CST_PTR (exp));
2926 case FIXED_CST:
2927 return fixed_hash (TREE_FIXED_CST_PTR (exp));
2929 case STRING_CST:
2930 p = TREE_STRING_POINTER (exp);
2931 len = TREE_STRING_LENGTH (exp);
2932 break;
2934 case COMPLEX_CST:
2935 return (const_hash_1 (TREE_REALPART (exp)) * 5
2936 + const_hash_1 (TREE_IMAGPART (exp)));
2938 case VECTOR_CST:
2940 unsigned i;
2942 hi = 7 + VECTOR_CST_NELTS (exp);
2944 for (i = 0; i < VECTOR_CST_NELTS (exp); ++i)
2945 hi = hi * 563 + const_hash_1 (VECTOR_CST_ELT (exp, i));
2947 return hi;
2950 case CONSTRUCTOR:
2952 unsigned HOST_WIDE_INT idx;
2953 tree value;
2955 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2957 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
2958 if (value)
2959 hi = hi * 603 + const_hash_1 (value);
2961 return hi;
2964 case ADDR_EXPR:
2965 case FDESC_EXPR:
2967 struct addr_const value;
2969 decode_addr_const (exp, &value);
2970 switch (GET_CODE (value.base))
2972 case SYMBOL_REF:
2973 /* Don't hash the address of the SYMBOL_REF;
2974 only use the offset and the symbol name. */
2975 hi = value.offset;
2976 p = XSTR (value.base, 0);
2977 for (i = 0; p[i] != 0; i++)
2978 hi = ((hi * 613) + (unsigned) (p[i]));
2979 break;
2981 case LABEL_REF:
2982 hi = (value.offset
2983 + CODE_LABEL_NUMBER (LABEL_REF_LABEL (value.base)) * 13);
2984 break;
2986 default:
2987 gcc_unreachable ();
2990 return hi;
2992 case PLUS_EXPR:
2993 case POINTER_PLUS_EXPR:
2994 case MINUS_EXPR:
2995 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2996 + const_hash_1 (TREE_OPERAND (exp, 1)));
2998 CASE_CONVERT:
2999 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
3001 default:
3002 /* A language specific constant. Just hash the code. */
3003 return code;
3006 /* Compute hashing function. */
3007 hi = len;
3008 for (i = 0; i < len; i++)
3009 hi = ((hi * 613) + (unsigned) (p[i]));
3011 return hi;
3014 /* Wrapper of compare_constant, for the htab interface. */
3015 bool
3016 tree_descriptor_hasher::equal (constant_descriptor_tree *c1,
3017 constant_descriptor_tree *c2)
3019 if (c1->hash != c2->hash)
3020 return 0;
3021 return compare_constant (c1->value, c2->value);
3024 /* Compare t1 and t2, and return 1 only if they are known to result in
3025 the same bit pattern on output. */
3027 static int
3028 compare_constant (const tree t1, const tree t2)
3030 enum tree_code typecode;
3032 if (t1 == NULL_TREE)
3033 return t2 == NULL_TREE;
3034 if (t2 == NULL_TREE)
3035 return 0;
3037 if (TREE_CODE (t1) != TREE_CODE (t2))
3038 return 0;
3040 switch (TREE_CODE (t1))
3042 case INTEGER_CST:
3043 /* Integer constants are the same only if the same width of type. */
3044 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3045 return 0;
3046 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3047 return 0;
3048 return tree_int_cst_equal (t1, t2);
3050 case REAL_CST:
3051 /* Real constants are the same only if the same width of type. */
3052 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3053 return 0;
3055 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
3057 case FIXED_CST:
3058 /* Fixed constants are the same only if the same width of type. */
3059 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
3060 return 0;
3062 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
3064 case STRING_CST:
3065 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
3066 return 0;
3068 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
3069 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
3070 TREE_STRING_LENGTH (t1)));
3072 case COMPLEX_CST:
3073 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
3074 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
3076 case VECTOR_CST:
3078 unsigned i;
3080 if (VECTOR_CST_NELTS (t1) != VECTOR_CST_NELTS (t2))
3081 return 0;
3083 for (i = 0; i < VECTOR_CST_NELTS (t1); ++i)
3084 if (!compare_constant (VECTOR_CST_ELT (t1, i),
3085 VECTOR_CST_ELT (t2, i)))
3086 return 0;
3088 return 1;
3091 case CONSTRUCTOR:
3093 vec<constructor_elt, va_gc> *v1, *v2;
3094 unsigned HOST_WIDE_INT idx;
3096 typecode = TREE_CODE (TREE_TYPE (t1));
3097 if (typecode != TREE_CODE (TREE_TYPE (t2)))
3098 return 0;
3100 if (typecode == ARRAY_TYPE)
3102 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
3103 /* For arrays, check that the sizes all match. */
3104 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
3105 || size_1 == -1
3106 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
3107 return 0;
3109 else
3111 /* For record and union constructors, require exact type
3112 equality. */
3113 if (TREE_TYPE (t1) != TREE_TYPE (t2))
3114 return 0;
3117 v1 = CONSTRUCTOR_ELTS (t1);
3118 v2 = CONSTRUCTOR_ELTS (t2);
3119 if (vec_safe_length (v1) != vec_safe_length (v2))
3120 return 0;
3122 for (idx = 0; idx < vec_safe_length (v1); ++idx)
3124 constructor_elt *c1 = &(*v1)[idx];
3125 constructor_elt *c2 = &(*v2)[idx];
3127 /* Check that each value is the same... */
3128 if (!compare_constant (c1->value, c2->value))
3129 return 0;
3130 /* ... and that they apply to the same fields! */
3131 if (typecode == ARRAY_TYPE)
3133 if (!compare_constant (c1->index, c2->index))
3134 return 0;
3136 else
3138 if (c1->index != c2->index)
3139 return 0;
3143 return 1;
3146 case ADDR_EXPR:
3147 case FDESC_EXPR:
3149 struct addr_const value1, value2;
3150 enum rtx_code code;
3151 int ret;
3153 decode_addr_const (t1, &value1);
3154 decode_addr_const (t2, &value2);
3156 if (value1.offset != value2.offset)
3157 return 0;
3159 code = GET_CODE (value1.base);
3160 if (code != GET_CODE (value2.base))
3161 return 0;
3163 switch (code)
3165 case SYMBOL_REF:
3166 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3167 break;
3169 case LABEL_REF:
3170 ret = (CODE_LABEL_NUMBER (LABEL_REF_LABEL (value1.base))
3171 == CODE_LABEL_NUMBER (LABEL_REF_LABEL (value2.base)));
3172 break;
3174 default:
3175 gcc_unreachable ();
3177 return ret;
3180 case PLUS_EXPR:
3181 case POINTER_PLUS_EXPR:
3182 case MINUS_EXPR:
3183 case RANGE_EXPR:
3184 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3185 && compare_constant (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3187 CASE_CONVERT:
3188 case VIEW_CONVERT_EXPR:
3189 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3191 default:
3192 return 0;
3195 gcc_unreachable ();
3198 /* Return the section into which constant EXP should be placed. */
3200 static section *
3201 get_constant_section (tree exp, unsigned int align)
3203 return targetm.asm_out.select_section (exp,
3204 compute_reloc_for_constant (exp),
3205 align);
3208 /* Return the size of constant EXP in bytes. */
3210 static HOST_WIDE_INT
3211 get_constant_size (tree exp)
3213 HOST_WIDE_INT size;
3215 size = int_size_in_bytes (TREE_TYPE (exp));
3216 if (TREE_CODE (exp) == STRING_CST)
3217 size = MAX (TREE_STRING_LENGTH (exp), size);
3218 return size;
3221 /* Subroutine of output_constant_def:
3222 No constant equal to EXP is known to have been output.
3223 Make a constant descriptor to enter EXP in the hash table.
3224 Assign the label number and construct RTL to refer to the
3225 constant's location in memory.
3226 Caller is responsible for updating the hash table. */
3228 static struct constant_descriptor_tree *
3229 build_constant_desc (tree exp)
3231 struct constant_descriptor_tree *desc;
3232 rtx symbol, rtl;
3233 char label[256];
3234 int labelno;
3235 tree decl;
3237 desc = ggc_alloc<constant_descriptor_tree> ();
3238 desc->value = exp;
3240 /* Create a string containing the label name, in LABEL. */
3241 labelno = const_labelno++;
3242 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3244 /* Construct the VAR_DECL associated with the constant. */
3245 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3246 TREE_TYPE (exp));
3247 DECL_ARTIFICIAL (decl) = 1;
3248 DECL_IGNORED_P (decl) = 1;
3249 TREE_READONLY (decl) = 1;
3250 TREE_STATIC (decl) = 1;
3251 TREE_ADDRESSABLE (decl) = 1;
3252 /* We don't set the RTL yet as this would cause varpool to assume that the
3253 variable is referenced. Moreover, it would just be dropped in LTO mode.
3254 Instead we set the flag that will be recognized in make_decl_rtl. */
3255 DECL_IN_CONSTANT_POOL (decl) = 1;
3256 DECL_INITIAL (decl) = desc->value;
3257 /* ??? CONSTANT_ALIGNMENT hasn't been updated for vector types on most
3258 architectures so use DATA_ALIGNMENT as well, except for strings. */
3259 if (TREE_CODE (exp) == STRING_CST)
3261 #ifdef CONSTANT_ALIGNMENT
3262 DECL_ALIGN (decl) = CONSTANT_ALIGNMENT (exp, DECL_ALIGN (decl));
3263 #endif
3265 else
3266 align_variable (decl, 0);
3268 /* Now construct the SYMBOL_REF and the MEM. */
3269 if (use_object_blocks_p ())
3271 section *sect = get_constant_section (exp, DECL_ALIGN (decl));
3272 symbol = create_block_symbol (ggc_strdup (label),
3273 get_block_for_section (sect), -1);
3275 else
3276 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3277 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3278 SET_SYMBOL_REF_DECL (symbol, decl);
3279 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3281 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3282 set_mem_attributes (rtl, exp, 1);
3283 set_mem_alias_set (rtl, 0);
3285 /* We cannot share RTX'es in pool entries.
3286 Mark this piece of RTL as required for unsharing. */
3287 RTX_FLAG (rtl, used) = 1;
3289 /* Set flags or add text to the name to record information, such as
3290 that it is a local symbol. If the name is changed, the macro
3291 ASM_OUTPUT_LABELREF will have to know how to strip this
3292 information. This call might invalidate our local variable
3293 SYMBOL; we can't use it afterward. */
3294 targetm.encode_section_info (exp, rtl, true);
3296 desc->rtl = rtl;
3298 return desc;
3301 /* Return an rtx representing a reference to constant data in memory
3302 for the constant expression EXP.
3304 If assembler code for such a constant has already been output,
3305 return an rtx to refer to it.
3306 Otherwise, output such a constant in memory
3307 and generate an rtx for it.
3309 If DEFER is nonzero, this constant can be deferred and output only
3310 if referenced in the function after all optimizations.
3312 `const_desc_table' records which constants already have label strings. */
3315 output_constant_def (tree exp, int defer)
3317 struct constant_descriptor_tree *desc;
3318 struct constant_descriptor_tree key;
3320 /* Look up EXP in the table of constant descriptors. If we didn't find
3321 it, create a new one. */
3322 key.value = exp;
3323 key.hash = const_hash_1 (exp);
3324 constant_descriptor_tree **loc
3325 = const_desc_htab->find_slot_with_hash (&key, key.hash, INSERT);
3327 desc = *loc;
3328 if (desc == 0)
3330 desc = build_constant_desc (exp);
3331 desc->hash = key.hash;
3332 *loc = desc;
3335 maybe_output_constant_def_contents (desc, defer);
3336 return desc->rtl;
3339 /* Subroutine of output_constant_def: Decide whether or not we need to
3340 output the constant DESC now, and if so, do it. */
3341 static void
3342 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3343 int defer)
3345 rtx symbol = XEXP (desc->rtl, 0);
3346 tree exp = desc->value;
3348 if (flag_syntax_only)
3349 return;
3351 if (TREE_ASM_WRITTEN (exp))
3352 /* Already output; don't do it again. */
3353 return;
3355 /* We can always defer constants as long as the context allows
3356 doing so. */
3357 if (defer)
3359 /* Increment n_deferred_constants if it exists. It needs to be at
3360 least as large as the number of constants actually referred to
3361 by the function. If it's too small we'll stop looking too early
3362 and fail to emit constants; if it's too large we'll only look
3363 through the entire function when we could have stopped earlier. */
3364 if (cfun)
3365 n_deferred_constants++;
3366 return;
3369 output_constant_def_contents (symbol);
3372 /* Subroutine of output_constant_def_contents. Output the definition
3373 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3374 constant's alignment in bits. */
3376 static void
3377 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3379 HOST_WIDE_INT size;
3381 size = get_constant_size (exp);
3383 /* Do any machine/system dependent processing of the constant. */
3384 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3386 /* Output the value of EXP. */
3387 output_constant (exp, size, align);
3389 targetm.asm_out.decl_end ();
3392 /* We must output the constant data referred to by SYMBOL; do so. */
3394 static void
3395 output_constant_def_contents (rtx symbol)
3397 tree decl = SYMBOL_REF_DECL (symbol);
3398 tree exp = DECL_INITIAL (decl);
3399 unsigned int align;
3400 bool asan_protected = false;
3402 /* Make sure any other constants whose addresses appear in EXP
3403 are assigned label numbers. */
3404 output_addressed_constants (exp);
3406 /* We are no longer deferring this constant. */
3407 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3409 if ((flag_sanitize & SANITIZE_ADDRESS)
3410 && TREE_CODE (exp) == STRING_CST
3411 && asan_protect_global (exp))
3413 asan_protected = true;
3414 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
3415 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
3418 /* If the constant is part of an object block, make sure that the
3419 decl has been positioned within its block, but do not write out
3420 its definition yet. output_object_blocks will do that later. */
3421 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3422 place_block_symbol (symbol);
3423 else
3425 align = DECL_ALIGN (decl);
3426 switch_to_section (get_constant_section (exp, align));
3427 if (align > BITS_PER_UNIT)
3428 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3429 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3430 if (asan_protected)
3432 HOST_WIDE_INT size = get_constant_size (exp);
3433 assemble_zeros (asan_red_zone_size (size));
3438 /* Look up EXP in the table of constant descriptors. Return the rtl
3439 if it has been emitted, else null. */
3442 lookup_constant_def (tree exp)
3444 struct constant_descriptor_tree key;
3446 key.value = exp;
3447 key.hash = const_hash_1 (exp);
3448 constant_descriptor_tree *desc
3449 = const_desc_htab->find_with_hash (&key, key.hash);
3451 return (desc ? desc->rtl : NULL_RTX);
3454 /* Return a tree representing a reference to constant data in memory
3455 for the constant expression EXP.
3457 This is the counterpart of output_constant_def at the Tree level. */
3459 tree
3460 tree_output_constant_def (tree exp)
3462 struct constant_descriptor_tree *desc, key;
3463 tree decl;
3465 /* Look up EXP in the table of constant descriptors. If we didn't find
3466 it, create a new one. */
3467 key.value = exp;
3468 key.hash = const_hash_1 (exp);
3469 constant_descriptor_tree **loc
3470 = const_desc_htab->find_slot_with_hash (&key, key.hash, INSERT);
3472 desc = *loc;
3473 if (desc == 0)
3475 desc = build_constant_desc (exp);
3476 desc->hash = key.hash;
3477 *loc = desc;
3480 decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3481 varpool_node::finalize_decl (decl);
3482 return decl;
3485 struct GTY((chain_next ("%h.next"), for_user)) constant_descriptor_rtx {
3486 struct constant_descriptor_rtx *next;
3487 rtx mem;
3488 rtx sym;
3489 rtx constant;
3490 HOST_WIDE_INT offset;
3491 hashval_t hash;
3492 machine_mode mode;
3493 unsigned int align;
3494 int labelno;
3495 int mark;
3498 struct const_rtx_desc_hasher : ggc_hasher<constant_descriptor_rtx *>
3500 static hashval_t hash (constant_descriptor_rtx *);
3501 static bool equal (constant_descriptor_rtx *, constant_descriptor_rtx *);
3504 /* Used in the hash tables to avoid outputting the same constant
3505 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3506 are output once per function, not once per file. */
3507 /* ??? Only a few targets need per-function constant pools. Most
3508 can use one per-file pool. Should add a targetm bit to tell the
3509 difference. */
3511 struct GTY(()) rtx_constant_pool {
3512 /* Pointers to first and last constant in pool, as ordered by offset. */
3513 struct constant_descriptor_rtx *first;
3514 struct constant_descriptor_rtx *last;
3516 /* Hash facility for making memory-constants from constant rtl-expressions.
3517 It is used on RISC machines where immediate integer arguments and
3518 constant addresses are restricted so that such constants must be stored
3519 in memory. */
3520 hash_table<const_rtx_desc_hasher> *const_rtx_htab;
3522 /* Current offset in constant pool (does not include any
3523 machine-specific header). */
3524 HOST_WIDE_INT offset;
3527 /* Hash and compare functions for const_rtx_htab. */
3529 hashval_t
3530 const_rtx_desc_hasher::hash (constant_descriptor_rtx *desc)
3532 return desc->hash;
3535 bool
3536 const_rtx_desc_hasher::equal (constant_descriptor_rtx *x,
3537 constant_descriptor_rtx *y)
3539 if (x->mode != y->mode)
3540 return 0;
3541 return rtx_equal_p (x->constant, y->constant);
3544 /* Hash one component of a constant. */
3546 static hashval_t
3547 const_rtx_hash_1 (const_rtx x)
3549 unsigned HOST_WIDE_INT hwi;
3550 machine_mode mode;
3551 enum rtx_code code;
3552 hashval_t h;
3553 int i;
3555 code = GET_CODE (x);
3556 mode = GET_MODE (x);
3557 h = (hashval_t) code * 1048573 + mode;
3559 switch (code)
3561 case CONST_INT:
3562 hwi = INTVAL (x);
3564 fold_hwi:
3566 int shift = sizeof (hashval_t) * CHAR_BIT;
3567 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3569 h ^= (hashval_t) hwi;
3570 for (i = 1; i < n; ++i)
3572 hwi >>= shift;
3573 h ^= (hashval_t) hwi;
3576 break;
3578 case CONST_WIDE_INT:
3579 hwi = GET_MODE_PRECISION (mode);
3581 for (i = 0; i < CONST_WIDE_INT_NUNITS (x); i++)
3582 hwi ^= CONST_WIDE_INT_ELT (x, i);
3583 goto fold_hwi;
3586 case CONST_DOUBLE:
3587 if (TARGET_SUPPORTS_WIDE_INT == 0 && mode == VOIDmode)
3589 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3590 goto fold_hwi;
3592 else
3593 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3594 break;
3596 case CONST_FIXED:
3597 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3598 break;
3600 case SYMBOL_REF:
3601 h ^= htab_hash_string (XSTR (x, 0));
3602 break;
3604 case LABEL_REF:
3605 h = h * 251 + CODE_LABEL_NUMBER (LABEL_REF_LABEL (x));
3606 break;
3608 case UNSPEC:
3609 case UNSPEC_VOLATILE:
3610 h = h * 251 + XINT (x, 1);
3611 break;
3613 default:
3614 break;
3617 return h;
3620 /* Compute a hash value for X, which should be a constant. */
3622 static hashval_t
3623 const_rtx_hash (rtx x)
3625 hashval_t h = 0;
3626 subrtx_iterator::array_type array;
3627 FOR_EACH_SUBRTX (iter, array, x, ALL)
3628 h = h * 509 + const_rtx_hash_1 (*iter);
3629 return h;
3633 /* Create and return a new rtx constant pool. */
3635 static struct rtx_constant_pool *
3636 create_constant_pool (void)
3638 struct rtx_constant_pool *pool;
3640 pool = ggc_alloc<rtx_constant_pool> ();
3641 pool->const_rtx_htab = hash_table<const_rtx_desc_hasher>::create_ggc (31);
3642 pool->first = NULL;
3643 pool->last = NULL;
3644 pool->offset = 0;
3645 return pool;
3648 /* Initialize constant pool hashing for a new function. */
3650 void
3651 init_varasm_status (void)
3653 crtl->varasm.pool = create_constant_pool ();
3654 crtl->varasm.deferred_constants = 0;
3657 /* Given a MINUS expression, simplify it if both sides
3658 include the same symbol. */
3661 simplify_subtraction (rtx x)
3663 rtx r = simplify_rtx (x);
3664 return r ? r : x;
3667 /* Given a constant rtx X, make (or find) a memory constant for its value
3668 and return a MEM rtx to refer to it in memory. */
3671 force_const_mem (machine_mode mode, rtx x)
3673 struct constant_descriptor_rtx *desc, tmp;
3674 struct rtx_constant_pool *pool;
3675 char label[256];
3676 rtx def, symbol;
3677 hashval_t hash;
3678 unsigned int align;
3679 constant_descriptor_rtx **slot;
3681 /* If we're not allowed to drop X into the constant pool, don't. */
3682 if (targetm.cannot_force_const_mem (mode, x))
3683 return NULL_RTX;
3685 /* Record that this function has used a constant pool entry. */
3686 crtl->uses_const_pool = 1;
3688 /* Decide which pool to use. */
3689 pool = (targetm.use_blocks_for_constant_p (mode, x)
3690 ? shared_constant_pool
3691 : crtl->varasm.pool);
3693 /* Lookup the value in the hashtable. */
3694 tmp.constant = x;
3695 tmp.mode = mode;
3696 hash = const_rtx_hash (x);
3697 slot = pool->const_rtx_htab->find_slot_with_hash (&tmp, hash, INSERT);
3698 desc = *slot;
3700 /* If the constant was already present, return its memory. */
3701 if (desc)
3702 return copy_rtx (desc->mem);
3704 /* Otherwise, create a new descriptor. */
3705 desc = ggc_alloc<constant_descriptor_rtx> ();
3706 *slot = desc;
3708 /* Align the location counter as required by EXP's data type. */
3709 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3710 #ifdef CONSTANT_ALIGNMENT
3712 tree type = lang_hooks.types.type_for_mode (mode, 0);
3713 if (type != NULL_TREE)
3714 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3716 #endif
3718 pool->offset += (align / BITS_PER_UNIT) - 1;
3719 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3721 desc->next = NULL;
3722 desc->constant = copy_rtx (tmp.constant);
3723 desc->offset = pool->offset;
3724 desc->hash = hash;
3725 desc->mode = mode;
3726 desc->align = align;
3727 desc->labelno = const_labelno;
3728 desc->mark = 0;
3730 pool->offset += GET_MODE_SIZE (mode);
3731 if (pool->last)
3732 pool->last->next = desc;
3733 else
3734 pool->first = pool->last = desc;
3735 pool->last = desc;
3737 /* Create a string containing the label name, in LABEL. */
3738 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3739 ++const_labelno;
3741 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3742 the constants pool. */
3743 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3745 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3746 symbol = create_block_symbol (ggc_strdup (label),
3747 get_block_for_section (sect), -1);
3749 else
3750 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3751 desc->sym = symbol;
3752 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3753 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3754 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3756 /* Construct the MEM. */
3757 desc->mem = def = gen_const_mem (mode, symbol);
3758 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3759 set_mem_align (def, align);
3761 /* If we're dropping a label to the constant pool, make sure we
3762 don't delete it. */
3763 if (GET_CODE (x) == LABEL_REF)
3764 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3766 return copy_rtx (def);
3769 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3772 get_pool_constant (const_rtx addr)
3774 return SYMBOL_REF_CONSTANT (addr)->constant;
3777 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3778 and whether it has been output or not. */
3781 get_pool_constant_mark (rtx addr, bool *pmarked)
3783 struct constant_descriptor_rtx *desc;
3785 desc = SYMBOL_REF_CONSTANT (addr);
3786 *pmarked = (desc->mark != 0);
3787 return desc->constant;
3790 /* Similar, return the mode. */
3792 machine_mode
3793 get_pool_mode (const_rtx addr)
3795 return SYMBOL_REF_CONSTANT (addr)->mode;
3798 /* Return the size of the constant pool. */
3801 get_pool_size (void)
3803 return crtl->varasm.pool->offset;
3806 /* Worker function for output_constant_pool_1. Emit assembly for X
3807 in MODE with known alignment ALIGN. */
3809 static void
3810 output_constant_pool_2 (machine_mode mode, rtx x, unsigned int align)
3812 switch (GET_MODE_CLASS (mode))
3814 case MODE_FLOAT:
3815 case MODE_DECIMAL_FLOAT:
3817 REAL_VALUE_TYPE r;
3819 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3820 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3821 assemble_real (r, mode, align);
3822 break;
3825 case MODE_INT:
3826 case MODE_PARTIAL_INT:
3827 case MODE_FRACT:
3828 case MODE_UFRACT:
3829 case MODE_ACCUM:
3830 case MODE_UACCUM:
3831 case MODE_POINTER_BOUNDS:
3832 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3833 break;
3835 case MODE_VECTOR_FLOAT:
3836 case MODE_VECTOR_INT:
3837 case MODE_VECTOR_FRACT:
3838 case MODE_VECTOR_UFRACT:
3839 case MODE_VECTOR_ACCUM:
3840 case MODE_VECTOR_UACCUM:
3842 int i, units;
3843 machine_mode submode = GET_MODE_INNER (mode);
3844 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3846 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3847 units = CONST_VECTOR_NUNITS (x);
3849 for (i = 0; i < units; i++)
3851 rtx elt = CONST_VECTOR_ELT (x, i);
3852 output_constant_pool_2 (submode, elt, i ? subalign : align);
3855 break;
3857 default:
3858 gcc_unreachable ();
3862 /* Worker function for output_constant_pool. Emit constant DESC,
3863 giving it ALIGN bits of alignment. */
3865 static void
3866 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3867 unsigned int align)
3869 rtx x, tmp;
3871 x = desc->constant;
3873 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3874 whose CODE_LABEL has been deleted. This can occur if a jump table
3875 is eliminated by optimization. If so, write a constant of zero
3876 instead. Note that this can also happen by turning the
3877 CODE_LABEL into a NOTE. */
3878 /* ??? This seems completely and utterly wrong. Certainly it's
3879 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3880 functioning even with rtx_insn::deleted and friends. */
3882 tmp = x;
3883 switch (GET_CODE (tmp))
3885 case CONST:
3886 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3887 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
3888 break;
3889 tmp = XEXP (XEXP (tmp, 0), 0);
3890 /* FALLTHRU */
3892 case LABEL_REF:
3893 tmp = LABEL_REF_LABEL (tmp);
3894 gcc_assert (!as_a<rtx_insn *> (tmp)->deleted ());
3895 gcc_assert (!NOTE_P (tmp)
3896 || NOTE_KIND (tmp) != NOTE_INSN_DELETED);
3897 break;
3899 default:
3900 break;
3903 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3904 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3905 align, desc->labelno, done);
3906 #endif
3908 assemble_align (align);
3910 /* Output the label. */
3911 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3913 /* Output the data. */
3914 output_constant_pool_2 (desc->mode, x, align);
3916 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3917 sections have proper size. */
3918 if (align > GET_MODE_BITSIZE (desc->mode)
3919 && in_section
3920 && (in_section->common.flags & SECTION_MERGE))
3921 assemble_align (align);
3923 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3924 done:
3925 #endif
3926 return;
3929 /* Mark all constants that are referenced by SYMBOL_REFs in X.
3930 Emit referenced deferred strings. */
3932 static void
3933 mark_constants_in_pattern (rtx insn)
3935 subrtx_iterator::array_type array;
3936 FOR_EACH_SUBRTX (iter, array, PATTERN (insn), ALL)
3938 const_rtx x = *iter;
3939 if (GET_CODE (x) == SYMBOL_REF)
3941 if (CONSTANT_POOL_ADDRESS_P (x))
3943 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
3944 if (desc->mark == 0)
3946 desc->mark = 1;
3947 iter.substitute (desc->constant);
3950 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3952 tree decl = SYMBOL_REF_DECL (x);
3953 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
3955 n_deferred_constants--;
3956 output_constant_def_contents (CONST_CAST_RTX (x));
3963 /* Look through appropriate parts of INSN, marking all entries in the
3964 constant pool which are actually being used. Entries that are only
3965 referenced by other constants are also marked as used. Emit
3966 deferred strings that are used. */
3968 static void
3969 mark_constants (rtx_insn *insn)
3971 if (!INSN_P (insn))
3972 return;
3974 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3975 insns, not any notes that may be attached. We don't want to mark
3976 a constant just because it happens to appear in a REG_EQUIV note. */
3977 if (rtx_sequence *seq = dyn_cast <rtx_sequence *> (PATTERN (insn)))
3979 int i, n = seq->len ();
3980 for (i = 0; i < n; ++i)
3982 rtx subinsn = seq->element (i);
3983 if (INSN_P (subinsn))
3984 mark_constants_in_pattern (subinsn);
3987 else
3988 mark_constants_in_pattern (insn);
3991 /* Look through the instructions for this function, and mark all the
3992 entries in POOL which are actually being used. Emit deferred constants
3993 which have indeed been used. */
3995 static void
3996 mark_constant_pool (void)
3998 rtx_insn *insn;
4000 if (!crtl->uses_const_pool && n_deferred_constants == 0)
4001 return;
4003 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4004 mark_constants (insn);
4007 /* Write all the constants in POOL. */
4009 static void
4010 output_constant_pool_contents (struct rtx_constant_pool *pool)
4012 struct constant_descriptor_rtx *desc;
4014 for (desc = pool->first; desc ; desc = desc->next)
4015 if (desc->mark)
4017 /* If the constant is part of an object_block, make sure that
4018 the constant has been positioned within its block, but do not
4019 write out its definition yet. output_object_blocks will do
4020 that later. */
4021 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
4022 && SYMBOL_REF_BLOCK (desc->sym))
4023 place_block_symbol (desc->sym);
4024 else
4026 switch_to_section (targetm.asm_out.select_rtx_section
4027 (desc->mode, desc->constant, desc->align));
4028 output_constant_pool_1 (desc, desc->align);
4033 /* Mark all constants that are used in the current function, then write
4034 out the function's private constant pool. */
4036 static void
4037 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
4038 tree fndecl ATTRIBUTE_UNUSED)
4040 struct rtx_constant_pool *pool = crtl->varasm.pool;
4042 /* It is possible for gcc to call force_const_mem and then to later
4043 discard the instructions which refer to the constant. In such a
4044 case we do not need to output the constant. */
4045 mark_constant_pool ();
4047 #ifdef ASM_OUTPUT_POOL_PROLOGUE
4048 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
4049 #endif
4051 output_constant_pool_contents (pool);
4053 #ifdef ASM_OUTPUT_POOL_EPILOGUE
4054 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
4055 #endif
4058 /* Write the contents of the shared constant pool. */
4060 void
4061 output_shared_constant_pool (void)
4063 output_constant_pool_contents (shared_constant_pool);
4066 /* Determine what kind of relocations EXP may need. */
4069 compute_reloc_for_constant (tree exp)
4071 int reloc = 0, reloc2;
4072 tree tem;
4074 switch (TREE_CODE (exp))
4076 case ADDR_EXPR:
4077 case FDESC_EXPR:
4078 /* Go inside any operations that get_inner_reference can handle and see
4079 if what's inside is a constant: no need to do anything here for
4080 addresses of variables or functions. */
4081 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4082 tem = TREE_OPERAND (tem, 0))
4085 if (TREE_CODE (tem) == MEM_REF
4086 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4088 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4089 break;
4092 if (!targetm.binds_local_p (tem))
4093 reloc |= 2;
4094 else
4095 reloc |= 1;
4096 break;
4098 case PLUS_EXPR:
4099 case POINTER_PLUS_EXPR:
4100 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4101 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4102 break;
4104 case MINUS_EXPR:
4105 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4106 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4107 /* The difference of two local labels is computable at link time. */
4108 if (reloc == 1 && reloc2 == 1)
4109 reloc = 0;
4110 else
4111 reloc |= reloc2;
4112 break;
4114 CASE_CONVERT:
4115 case VIEW_CONVERT_EXPR:
4116 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4117 break;
4119 case CONSTRUCTOR:
4121 unsigned HOST_WIDE_INT idx;
4122 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4123 if (tem != 0)
4124 reloc |= compute_reloc_for_constant (tem);
4126 break;
4128 default:
4129 break;
4131 return reloc;
4134 /* Find all the constants whose addresses are referenced inside of EXP,
4135 and make sure assembler code with a label has been output for each one.
4136 Indicate whether an ADDR_EXPR has been encountered. */
4138 static void
4139 output_addressed_constants (tree exp)
4141 tree tem;
4143 switch (TREE_CODE (exp))
4145 case ADDR_EXPR:
4146 case FDESC_EXPR:
4147 /* Go inside any operations that get_inner_reference can handle and see
4148 if what's inside is a constant: no need to do anything here for
4149 addresses of variables or functions. */
4150 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4151 tem = TREE_OPERAND (tem, 0))
4154 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4155 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4156 tem = DECL_INITIAL (tem);
4158 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4159 output_constant_def (tem, 0);
4161 if (TREE_CODE (tem) == MEM_REF)
4162 output_addressed_constants (TREE_OPERAND (tem, 0));
4163 break;
4165 case PLUS_EXPR:
4166 case POINTER_PLUS_EXPR:
4167 case MINUS_EXPR:
4168 output_addressed_constants (TREE_OPERAND (exp, 1));
4169 /* Fall through. */
4171 CASE_CONVERT:
4172 case VIEW_CONVERT_EXPR:
4173 output_addressed_constants (TREE_OPERAND (exp, 0));
4174 break;
4176 case CONSTRUCTOR:
4178 unsigned HOST_WIDE_INT idx;
4179 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4180 if (tem != 0)
4181 output_addressed_constants (tem);
4183 break;
4185 default:
4186 break;
4190 /* Whether a constructor CTOR is a valid static constant initializer if all
4191 its elements are. This used to be internal to initializer_constant_valid_p
4192 and has been exposed to let other functions like categorize_ctor_elements
4193 evaluate the property while walking a constructor for other purposes. */
4195 bool
4196 constructor_static_from_elts_p (const_tree ctor)
4198 return (TREE_CONSTANT (ctor)
4199 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4200 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4201 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4204 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4205 tree *cache);
4207 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4208 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4209 which are valid when ENDTYPE is an integer of any size; in
4210 particular, this does not accept a pointer minus a constant. This
4211 returns null_pointer_node if the VALUE is an absolute constant
4212 which can be used to initialize a static variable. Otherwise it
4213 returns NULL. */
4215 static tree
4216 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4218 tree op0, op1;
4220 if (!INTEGRAL_TYPE_P (endtype))
4221 return NULL_TREE;
4223 op0 = TREE_OPERAND (value, 0);
4224 op1 = TREE_OPERAND (value, 1);
4226 /* Like STRIP_NOPS except allow the operand mode to widen. This
4227 works around a feature of fold that simplifies (int)(p1 - p2) to
4228 ((int)p1 - (int)p2) under the theory that the narrower operation
4229 is cheaper. */
4231 while (CONVERT_EXPR_P (op0)
4232 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4234 tree inner = TREE_OPERAND (op0, 0);
4235 if (inner == error_mark_node
4236 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4237 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
4238 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4239 break;
4240 op0 = inner;
4243 while (CONVERT_EXPR_P (op1)
4244 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4246 tree inner = TREE_OPERAND (op1, 0);
4247 if (inner == error_mark_node
4248 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4249 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
4250 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4251 break;
4252 op1 = inner;
4255 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4256 if (!op0)
4257 return NULL_TREE;
4259 op1 = initializer_constant_valid_p_1 (op1, endtype,
4260 cache ? cache + 2 : NULL);
4261 /* Both initializers must be known. */
4262 if (op1)
4264 if (op0 == op1
4265 && (op0 == null_pointer_node
4266 || TREE_CODE (value) == MINUS_EXPR))
4267 return null_pointer_node;
4269 /* Support differences between labels. */
4270 if (TREE_CODE (op0) == LABEL_DECL
4271 && TREE_CODE (op1) == LABEL_DECL)
4272 return null_pointer_node;
4274 if (TREE_CODE (op0) == STRING_CST
4275 && TREE_CODE (op1) == STRING_CST
4276 && operand_equal_p (op0, op1, 1))
4277 return null_pointer_node;
4280 return NULL_TREE;
4283 /* Helper function of initializer_constant_valid_p.
4284 Return nonzero if VALUE is a valid constant-valued expression
4285 for use in initializing a static variable; one that can be an
4286 element of a "constant" initializer.
4288 Return null_pointer_node if the value is absolute;
4289 if it is relocatable, return the variable that determines the relocation.
4290 We assume that VALUE has been folded as much as possible;
4291 therefore, we do not need to check for such things as
4292 arithmetic-combinations of integers.
4294 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4296 static tree
4297 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4299 tree ret;
4301 switch (TREE_CODE (value))
4303 case CONSTRUCTOR:
4304 if (constructor_static_from_elts_p (value))
4306 unsigned HOST_WIDE_INT idx;
4307 tree elt;
4308 bool absolute = true;
4310 if (cache && cache[0] == value)
4311 return cache[1];
4312 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4314 tree reloc;
4315 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4316 NULL);
4317 if (!reloc)
4319 if (cache)
4321 cache[0] = value;
4322 cache[1] = NULL_TREE;
4324 return NULL_TREE;
4326 if (reloc != null_pointer_node)
4327 absolute = false;
4329 /* For a non-absolute relocation, there is no single
4330 variable that can be "the variable that determines the
4331 relocation." */
4332 if (cache)
4334 cache[0] = value;
4335 cache[1] = absolute ? null_pointer_node : error_mark_node;
4337 return absolute ? null_pointer_node : error_mark_node;
4340 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4342 case INTEGER_CST:
4343 case VECTOR_CST:
4344 case REAL_CST:
4345 case FIXED_CST:
4346 case STRING_CST:
4347 case COMPLEX_CST:
4348 return null_pointer_node;
4350 case ADDR_EXPR:
4351 case FDESC_EXPR:
4353 tree op0 = staticp (TREE_OPERAND (value, 0));
4354 if (op0)
4356 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4357 to be a constant, this is old-skool offsetof-like nonsense. */
4358 if (TREE_CODE (op0) == INDIRECT_REF
4359 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4360 return null_pointer_node;
4361 /* Taking the address of a nested function involves a trampoline,
4362 unless we don't need or want one. */
4363 if (TREE_CODE (op0) == FUNCTION_DECL
4364 && DECL_STATIC_CHAIN (op0)
4365 && !TREE_NO_TRAMPOLINE (value))
4366 return NULL_TREE;
4367 /* "&{...}" requires a temporary to hold the constructed
4368 object. */
4369 if (TREE_CODE (op0) == CONSTRUCTOR)
4370 return NULL_TREE;
4372 return op0;
4375 case NON_LVALUE_EXPR:
4376 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4377 endtype, cache);
4379 case VIEW_CONVERT_EXPR:
4381 tree src = TREE_OPERAND (value, 0);
4382 tree src_type = TREE_TYPE (src);
4383 tree dest_type = TREE_TYPE (value);
4385 /* Allow view-conversions from aggregate to non-aggregate type only
4386 if the bit pattern is fully preserved afterwards; otherwise, the
4387 RTL expander won't be able to apply a subsequent transformation
4388 to the underlying constructor. */
4389 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4391 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4392 return initializer_constant_valid_p_1 (src, endtype, cache);
4393 else
4394 return NULL_TREE;
4397 /* Allow all other kinds of view-conversion. */
4398 return initializer_constant_valid_p_1 (src, endtype, cache);
4401 CASE_CONVERT:
4403 tree src = TREE_OPERAND (value, 0);
4404 tree src_type = TREE_TYPE (src);
4405 tree dest_type = TREE_TYPE (value);
4407 /* Allow conversions between pointer types, floating-point
4408 types, and offset types. */
4409 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4410 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4411 || (TREE_CODE (dest_type) == OFFSET_TYPE
4412 && TREE_CODE (src_type) == OFFSET_TYPE))
4413 return initializer_constant_valid_p_1 (src, endtype, cache);
4415 /* Allow length-preserving conversions between integer types. */
4416 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4417 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4418 return initializer_constant_valid_p_1 (src, endtype, cache);
4420 /* Allow conversions between other integer types only if
4421 explicit value. */
4422 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type))
4424 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4425 if (inner == null_pointer_node)
4426 return null_pointer_node;
4427 break;
4430 /* Allow (int) &foo provided int is as wide as a pointer. */
4431 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4432 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4433 return initializer_constant_valid_p_1 (src, endtype, cache);
4435 /* Likewise conversions from int to pointers, but also allow
4436 conversions from 0. */
4437 if ((POINTER_TYPE_P (dest_type)
4438 || TREE_CODE (dest_type) == OFFSET_TYPE)
4439 && INTEGRAL_TYPE_P (src_type))
4441 if (TREE_CODE (src) == INTEGER_CST
4442 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4443 return null_pointer_node;
4444 if (integer_zerop (src))
4445 return null_pointer_node;
4446 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4447 return initializer_constant_valid_p_1 (src, endtype, cache);
4450 /* Allow conversions to struct or union types if the value
4451 inside is okay. */
4452 if (TREE_CODE (dest_type) == RECORD_TYPE
4453 || TREE_CODE (dest_type) == UNION_TYPE)
4454 return initializer_constant_valid_p_1 (src, endtype, cache);
4456 break;
4458 case POINTER_PLUS_EXPR:
4459 case PLUS_EXPR:
4460 /* Any valid floating-point constants will have been folded by now;
4461 with -frounding-math we hit this with addition of two constants. */
4462 if (TREE_CODE (endtype) == REAL_TYPE)
4463 return NULL_TREE;
4464 if (cache && cache[0] == value)
4465 return cache[1];
4466 if (! INTEGRAL_TYPE_P (endtype)
4467 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4469 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4470 tree valid0
4471 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4472 endtype, ncache);
4473 tree valid1
4474 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4475 endtype, ncache + 2);
4476 /* If either term is absolute, use the other term's relocation. */
4477 if (valid0 == null_pointer_node)
4478 ret = valid1;
4479 else if (valid1 == null_pointer_node)
4480 ret = valid0;
4481 /* Support narrowing pointer differences. */
4482 else
4483 ret = narrowing_initializer_constant_valid_p (value, endtype,
4484 ncache);
4486 else
4487 /* Support narrowing pointer differences. */
4488 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4489 if (cache)
4491 cache[0] = value;
4492 cache[1] = ret;
4494 return ret;
4496 case MINUS_EXPR:
4497 if (TREE_CODE (endtype) == REAL_TYPE)
4498 return NULL_TREE;
4499 if (cache && cache[0] == value)
4500 return cache[1];
4501 if (! INTEGRAL_TYPE_P (endtype)
4502 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4504 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4505 tree valid0
4506 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4507 endtype, ncache);
4508 tree valid1
4509 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4510 endtype, ncache + 2);
4511 /* Win if second argument is absolute. */
4512 if (valid1 == null_pointer_node)
4513 ret = valid0;
4514 /* Win if both arguments have the same relocation.
4515 Then the value is absolute. */
4516 else if (valid0 == valid1 && valid0 != 0)
4517 ret = null_pointer_node;
4518 /* Since GCC guarantees that string constants are unique in the
4519 generated code, a subtraction between two copies of the same
4520 constant string is absolute. */
4521 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4522 && valid1 && TREE_CODE (valid1) == STRING_CST
4523 && operand_equal_p (valid0, valid1, 1))
4524 ret = null_pointer_node;
4525 /* Support narrowing differences. */
4526 else
4527 ret = narrowing_initializer_constant_valid_p (value, endtype,
4528 ncache);
4530 else
4531 /* Support narrowing differences. */
4532 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4533 if (cache)
4535 cache[0] = value;
4536 cache[1] = ret;
4538 return ret;
4540 default:
4541 break;
4544 return NULL_TREE;
4547 /* Return nonzero if VALUE is a valid constant-valued expression
4548 for use in initializing a static variable; one that can be an
4549 element of a "constant" initializer.
4551 Return null_pointer_node if the value is absolute;
4552 if it is relocatable, return the variable that determines the relocation.
4553 We assume that VALUE has been folded as much as possible;
4554 therefore, we do not need to check for such things as
4555 arithmetic-combinations of integers. */
4556 tree
4557 initializer_constant_valid_p (tree value, tree endtype)
4559 return initializer_constant_valid_p_1 (value, endtype, NULL);
4562 /* Return true if VALUE is a valid constant-valued expression
4563 for use in initializing a static bit-field; one that can be
4564 an element of a "constant" initializer. */
4566 bool
4567 initializer_constant_valid_for_bitfield_p (tree value)
4569 /* For bitfields we support integer constants or possibly nested aggregates
4570 of such. */
4571 switch (TREE_CODE (value))
4573 case CONSTRUCTOR:
4575 unsigned HOST_WIDE_INT idx;
4576 tree elt;
4578 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4579 if (!initializer_constant_valid_for_bitfield_p (elt))
4580 return false;
4581 return true;
4584 case INTEGER_CST:
4585 case REAL_CST:
4586 return true;
4588 case VIEW_CONVERT_EXPR:
4589 case NON_LVALUE_EXPR:
4590 return
4591 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4593 default:
4594 break;
4597 return false;
4600 /* output_constructor outer state of relevance in recursive calls, typically
4601 for nested aggregate bitfields. */
4603 typedef struct {
4604 unsigned int bit_offset; /* current position in ... */
4605 int byte; /* ... the outer byte buffer. */
4606 } oc_outer_state;
4608 static unsigned HOST_WIDE_INT
4609 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int,
4610 oc_outer_state *);
4612 /* Output assembler code for constant EXP, with no label.
4613 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4614 Assumes output_addressed_constants has been done on EXP already.
4616 Generate at least SIZE bytes of assembler data, padding at the end
4617 with zeros if necessary. SIZE must always be specified. The returned
4618 value is the actual number of bytes of assembler data generated, which
4619 may be bigger than SIZE if the object contains a variable length field.
4621 SIZE is important for structure constructors,
4622 since trailing members may have been omitted from the constructor.
4623 It is also important for initialization of arrays from string constants
4624 since the full length of the string constant might not be wanted.
4625 It is also needed for initialization of unions, where the initializer's
4626 type is just one member, and that may not be as long as the union.
4628 There a case in which we would fail to output exactly SIZE bytes:
4629 for a structure constructor that wants to produce more than SIZE bytes.
4630 But such constructors will never be generated for any possible input.
4632 ALIGN is the alignment of the data in bits. */
4634 static unsigned HOST_WIDE_INT
4635 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align)
4637 enum tree_code code;
4638 unsigned HOST_WIDE_INT thissize;
4640 if (size == 0 || flag_syntax_only)
4641 return size;
4643 /* See if we're trying to initialize a pointer in a non-default mode
4644 to the address of some declaration somewhere. If the target says
4645 the mode is valid for pointers, assume the target has a way of
4646 resolving it. */
4647 if (TREE_CODE (exp) == NOP_EXPR
4648 && POINTER_TYPE_P (TREE_TYPE (exp))
4649 && targetm.addr_space.valid_pointer_mode
4650 (TYPE_MODE (TREE_TYPE (exp)),
4651 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4653 tree saved_type = TREE_TYPE (exp);
4655 /* Peel off any intermediate conversions-to-pointer for valid
4656 pointer modes. */
4657 while (TREE_CODE (exp) == NOP_EXPR
4658 && POINTER_TYPE_P (TREE_TYPE (exp))
4659 && targetm.addr_space.valid_pointer_mode
4660 (TYPE_MODE (TREE_TYPE (exp)),
4661 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4662 exp = TREE_OPERAND (exp, 0);
4664 /* If what we're left with is the address of something, we can
4665 convert the address to the final type and output it that
4666 way. */
4667 if (TREE_CODE (exp) == ADDR_EXPR)
4668 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4669 /* Likewise for constant ints. */
4670 else if (TREE_CODE (exp) == INTEGER_CST)
4671 exp = wide_int_to_tree (saved_type, exp);
4675 /* Eliminate any conversions since we'll be outputting the underlying
4676 constant. */
4677 while (CONVERT_EXPR_P (exp)
4678 || TREE_CODE (exp) == NON_LVALUE_EXPR
4679 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4681 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4682 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4684 /* Make sure eliminating the conversion is really a no-op, except with
4685 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4686 union types to allow for Ada unchecked unions. */
4687 if (type_size > op_size
4688 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4689 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4690 /* Keep the conversion. */
4691 break;
4692 else
4693 exp = TREE_OPERAND (exp, 0);
4696 code = TREE_CODE (TREE_TYPE (exp));
4697 thissize = int_size_in_bytes (TREE_TYPE (exp));
4699 /* Allow a constructor with no elements for any data type.
4700 This means to fill the space with zeros. */
4701 if (TREE_CODE (exp) == CONSTRUCTOR
4702 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4704 assemble_zeros (size);
4705 return size;
4708 if (TREE_CODE (exp) == FDESC_EXPR)
4710 #ifdef ASM_OUTPUT_FDESC
4711 HOST_WIDE_INT part = tree_to_shwi (TREE_OPERAND (exp, 1));
4712 tree decl = TREE_OPERAND (exp, 0);
4713 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4714 #else
4715 gcc_unreachable ();
4716 #endif
4717 return size;
4720 /* Now output the underlying data. If we've handling the padding, return.
4721 Otherwise, break and ensure SIZE is the size written. */
4722 switch (code)
4724 case BOOLEAN_TYPE:
4725 case INTEGER_TYPE:
4726 case ENUMERAL_TYPE:
4727 case POINTER_TYPE:
4728 case REFERENCE_TYPE:
4729 case OFFSET_TYPE:
4730 case FIXED_POINT_TYPE:
4731 case POINTER_BOUNDS_TYPE:
4732 case NULLPTR_TYPE:
4733 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
4734 EXPAND_INITIALIZER),
4735 MIN (size, thissize), align, 0))
4736 error ("initializer for integer/fixed-point value is too complicated");
4737 break;
4739 case REAL_TYPE:
4740 if (TREE_CODE (exp) != REAL_CST)
4741 error ("initializer for floating value is not a floating constant");
4742 else
4743 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)), align);
4744 break;
4746 case COMPLEX_TYPE:
4747 output_constant (TREE_REALPART (exp), thissize / 2, align);
4748 output_constant (TREE_IMAGPART (exp), thissize / 2,
4749 min_align (align, BITS_PER_UNIT * (thissize / 2)));
4750 break;
4752 case ARRAY_TYPE:
4753 case VECTOR_TYPE:
4754 switch (TREE_CODE (exp))
4756 case CONSTRUCTOR:
4757 return output_constructor (exp, size, align, NULL);
4758 case STRING_CST:
4759 thissize
4760 = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4761 assemble_string (TREE_STRING_POINTER (exp), thissize);
4762 break;
4763 case VECTOR_CST:
4765 machine_mode inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4766 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4767 int elt_size = GET_MODE_SIZE (inner);
4768 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align);
4769 thissize = elt_size;
4770 for (unsigned int i = 1; i < VECTOR_CST_NELTS (exp); i++)
4772 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign);
4773 thissize += elt_size;
4775 break;
4777 default:
4778 gcc_unreachable ();
4780 break;
4782 case RECORD_TYPE:
4783 case UNION_TYPE:
4784 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4785 return output_constructor (exp, size, align, NULL);
4787 case ERROR_MARK:
4788 return 0;
4790 default:
4791 gcc_unreachable ();
4794 if (size > thissize)
4795 assemble_zeros (size - thissize);
4797 return size;
4801 /* Subroutine of output_constructor, used for computing the size of
4802 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4803 type with an unspecified upper bound. */
4805 static unsigned HOST_WIDE_INT
4806 array_size_for_constructor (tree val)
4808 tree max_index;
4809 unsigned HOST_WIDE_INT cnt;
4810 tree index, value, tmp;
4811 offset_int i;
4813 /* This code used to attempt to handle string constants that are not
4814 arrays of single-bytes, but nothing else does, so there's no point in
4815 doing it here. */
4816 if (TREE_CODE (val) == STRING_CST)
4817 return TREE_STRING_LENGTH (val);
4819 max_index = NULL_TREE;
4820 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
4822 if (TREE_CODE (index) == RANGE_EXPR)
4823 index = TREE_OPERAND (index, 1);
4824 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
4825 max_index = index;
4828 if (max_index == NULL_TREE)
4829 return 0;
4831 /* Compute the total number of array elements. */
4832 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
4833 i = wi::to_offset (max_index) - wi::to_offset (tmp) + 1;
4835 /* Multiply by the array element unit size to find number of bytes. */
4836 i *= wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
4838 gcc_assert (wi::fits_uhwi_p (i));
4839 return i.to_uhwi ();
4842 /* Other datastructures + helpers for output_constructor. */
4844 /* output_constructor local state to support interaction with helpers. */
4846 typedef struct {
4848 /* Received arguments. */
4849 tree exp; /* Constructor expression. */
4850 tree type; /* Type of constructor expression. */
4851 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */
4852 unsigned int align; /* Known initial alignment. */
4853 tree min_index; /* Lower bound if specified for an array. */
4855 /* Output processing state. */
4856 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */
4857 int byte; /* Part of a bitfield byte yet to be output. */
4858 int last_relative_index; /* Implicit or explicit index of the last
4859 array element output within a bitfield. */
4860 bool byte_buffer_in_use; /* Whether BYTE is in use. */
4862 /* Current element. */
4863 tree field; /* Current field decl in a record. */
4864 tree val; /* Current element value. */
4865 tree index; /* Current element index. */
4867 } oc_local_state;
4869 /* Helper for output_constructor. From the current LOCAL state, output a
4870 RANGE_EXPR element. */
4872 static void
4873 output_constructor_array_range (oc_local_state *local)
4875 unsigned HOST_WIDE_INT fieldsize
4876 = int_size_in_bytes (TREE_TYPE (local->type));
4878 HOST_WIDE_INT lo_index
4879 = tree_to_shwi (TREE_OPERAND (local->index, 0));
4880 HOST_WIDE_INT hi_index
4881 = tree_to_shwi (TREE_OPERAND (local->index, 1));
4882 HOST_WIDE_INT index;
4884 unsigned int align2
4885 = min_align (local->align, fieldsize * BITS_PER_UNIT);
4887 for (index = lo_index; index <= hi_index; index++)
4889 /* Output the element's initial value. */
4890 if (local->val == NULL_TREE)
4891 assemble_zeros (fieldsize);
4892 else
4893 fieldsize = output_constant (local->val, fieldsize, align2);
4895 /* Count its size. */
4896 local->total_bytes += fieldsize;
4900 /* Helper for output_constructor. From the current LOCAL state, output a
4901 field element that is not true bitfield or part of an outer one. */
4903 static void
4904 output_constructor_regular_field (oc_local_state *local)
4906 /* Field size and position. Since this structure is static, we know the
4907 positions are constant. */
4908 unsigned HOST_WIDE_INT fieldsize;
4909 HOST_WIDE_INT fieldpos;
4911 unsigned int align2;
4913 if (local->index != NULL_TREE)
4915 /* Perform the index calculation in modulo arithmetic but
4916 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
4917 but we are using an unsigned sizetype. */
4918 unsigned prec = TYPE_PRECISION (sizetype);
4919 offset_int idx = wi::sext (wi::to_offset (local->index)
4920 - wi::to_offset (local->min_index), prec);
4921 fieldpos = (idx * wi::to_offset (TYPE_SIZE_UNIT (TREE_TYPE (local->val))))
4922 .to_short_addr ();
4924 else if (local->field != NULL_TREE)
4925 fieldpos = int_byte_position (local->field);
4926 else
4927 fieldpos = 0;
4929 /* Output any buffered-up bit-fields preceding this element. */
4930 if (local->byte_buffer_in_use)
4932 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4933 local->total_bytes++;
4934 local->byte_buffer_in_use = false;
4937 /* Advance to offset of this element.
4938 Note no alignment needed in an array, since that is guaranteed
4939 if each element has the proper size. */
4940 if ((local->field != NULL_TREE || local->index != NULL_TREE)
4941 && fieldpos > local->total_bytes)
4943 assemble_zeros (fieldpos - local->total_bytes);
4944 local->total_bytes = fieldpos;
4947 /* Find the alignment of this element. */
4948 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
4950 /* Determine size this element should occupy. */
4951 if (local->field)
4953 fieldsize = 0;
4955 /* If this is an array with an unspecified upper bound,
4956 the initializer determines the size. */
4957 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
4958 but we cannot do this until the deprecated support for
4959 initializing zero-length array members is removed. */
4960 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
4961 && TYPE_DOMAIN (TREE_TYPE (local->field))
4962 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field))))
4964 fieldsize = array_size_for_constructor (local->val);
4965 /* Given a non-empty initialization, this field had
4966 better be last. */
4967 gcc_assert (!fieldsize || !DECL_CHAIN (local->field));
4969 else
4970 fieldsize = tree_to_uhwi (DECL_SIZE_UNIT (local->field));
4972 else
4973 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
4975 /* Output the element's initial value. */
4976 if (local->val == NULL_TREE)
4977 assemble_zeros (fieldsize);
4978 else
4979 fieldsize = output_constant (local->val, fieldsize, align2);
4981 /* Count its size. */
4982 local->total_bytes += fieldsize;
4985 /* Helper for output_constructor. From the LOCAL state, output an element
4986 that is a true bitfield or part of an outer one. BIT_OFFSET is the offset
4987 from the start of a possibly ongoing outer byte buffer. */
4989 static void
4990 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
4992 /* Bit size of this element. */
4993 HOST_WIDE_INT ebitsize
4994 = (local->field
4995 ? tree_to_uhwi (DECL_SIZE (local->field))
4996 : tree_to_uhwi (TYPE_SIZE (TREE_TYPE (local->type))));
4998 /* Relative index of this element if this is an array component. */
4999 HOST_WIDE_INT relative_index
5000 = (!local->field
5001 ? (local->index
5002 ? (tree_to_shwi (local->index)
5003 - tree_to_shwi (local->min_index))
5004 : local->last_relative_index + 1)
5005 : 0);
5007 /* Bit position of this element from the start of the containing
5008 constructor. */
5009 HOST_WIDE_INT constructor_relative_ebitpos
5010 = (local->field
5011 ? int_bit_position (local->field)
5012 : ebitsize * relative_index);
5014 /* Bit position of this element from the start of a possibly ongoing
5015 outer byte buffer. */
5016 HOST_WIDE_INT byte_relative_ebitpos
5017 = bit_offset + constructor_relative_ebitpos;
5019 /* From the start of a possibly ongoing outer byte buffer, offsets to
5020 the first bit of this element and to the first bit past the end of
5021 this element. */
5022 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
5023 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
5025 local->last_relative_index = relative_index;
5027 if (local->val == NULL_TREE)
5028 local->val = integer_zero_node;
5030 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
5031 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
5032 local->val = TREE_OPERAND (local->val, 0);
5034 if (TREE_CODE (local->val) != INTEGER_CST
5035 && TREE_CODE (local->val) != CONSTRUCTOR)
5037 error ("invalid initial value for member %qE", DECL_NAME (local->field));
5038 return;
5041 /* If this field does not start in this (or next) byte, skip some bytes. */
5042 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5044 /* Output remnant of any bit field in previous bytes. */
5045 if (local->byte_buffer_in_use)
5047 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5048 local->total_bytes++;
5049 local->byte_buffer_in_use = false;
5052 /* If still not at proper byte, advance to there. */
5053 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5055 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
5056 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
5057 local->total_bytes = next_offset / BITS_PER_UNIT;
5061 /* Set up the buffer if necessary. */
5062 if (!local->byte_buffer_in_use)
5064 local->byte = 0;
5065 if (ebitsize > 0)
5066 local->byte_buffer_in_use = true;
5069 /* If this is nested constructor, recurse passing the bit offset and the
5070 pending data, then retrieve the new pending data afterwards. */
5071 if (TREE_CODE (local->val) == CONSTRUCTOR)
5073 oc_outer_state temp_state;
5074 temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5075 temp_state.byte = local->byte;
5076 local->total_bytes
5077 += output_constructor (local->val, 0, 0, &temp_state);
5078 local->byte = temp_state.byte;
5079 return;
5082 /* Otherwise, we must split the element into pieces that fall within
5083 separate bytes, and combine each byte with previous or following
5084 bit-fields. */
5085 while (next_offset < end_offset)
5087 int this_time;
5088 int shift;
5089 HOST_WIDE_INT value;
5090 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5091 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5093 /* Advance from byte to byte within this element when necessary. */
5094 while (next_byte != local->total_bytes)
5096 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5097 local->total_bytes++;
5098 local->byte = 0;
5101 /* Number of bits we can process at once (all part of the same byte). */
5102 this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5103 if (BYTES_BIG_ENDIAN)
5105 /* On big-endian machine, take the most significant bits (of the
5106 bits that are significant) first and put them into bytes from
5107 the most significant end. */
5108 shift = end_offset - next_offset - this_time;
5110 /* Don't try to take a bunch of bits that cross
5111 the word boundary in the INTEGER_CST. We can
5112 only select bits from one element. */
5113 if ((shift / HOST_BITS_PER_WIDE_INT)
5114 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5116 const int end = shift + this_time - 1;
5117 shift = end & -HOST_BITS_PER_WIDE_INT;
5118 this_time = end - shift + 1;
5121 /* Now get the bits from the appropriate constant word. */
5122 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5123 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5125 /* Get the result. This works only when:
5126 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5127 local->byte |= (((value >> shift)
5128 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5129 << (BITS_PER_UNIT - this_time - next_bit));
5131 else
5133 /* On little-endian machines, take the least significant bits of
5134 the value first and pack them starting at the least significant
5135 bits of the bytes. */
5136 shift = next_offset - byte_relative_ebitpos;
5138 /* Don't try to take a bunch of bits that cross
5139 the word boundary in the INTEGER_CST. We can
5140 only select bits from one element. */
5141 if ((shift / HOST_BITS_PER_WIDE_INT)
5142 != ((shift + this_time - 1) / HOST_BITS_PER_WIDE_INT))
5143 this_time
5144 = HOST_BITS_PER_WIDE_INT - (shift & (HOST_BITS_PER_WIDE_INT - 1));
5146 /* Now get the bits from the appropriate constant word. */
5147 value = TREE_INT_CST_ELT (local->val, shift / HOST_BITS_PER_WIDE_INT);
5148 shift = shift & (HOST_BITS_PER_WIDE_INT - 1);
5150 /* Get the result. This works only when:
5151 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5152 local->byte |= (((value >> shift)
5153 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5154 << next_bit);
5157 next_offset += this_time;
5158 local->byte_buffer_in_use = true;
5162 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5163 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5164 caller output state of relevance in recursive invocations. */
5166 static unsigned HOST_WIDE_INT
5167 output_constructor (tree exp, unsigned HOST_WIDE_INT size,
5168 unsigned int align, oc_outer_state *outer)
5170 unsigned HOST_WIDE_INT cnt;
5171 constructor_elt *ce;
5173 oc_local_state local;
5175 /* Setup our local state to communicate with helpers. */
5176 local.exp = exp;
5177 local.type = TREE_TYPE (exp);
5178 local.size = size;
5179 local.align = align;
5180 if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5181 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5182 else
5183 local.min_index = NULL_TREE;
5185 local.total_bytes = 0;
5186 local.byte_buffer_in_use = outer != NULL;
5187 local.byte = outer ? outer->byte : 0;
5188 local.last_relative_index = -1;
5190 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5192 /* As CE goes through the elements of the constant, FIELD goes through the
5193 structure fields if the constant is a structure. If the constant is a
5194 union, we override this by getting the field from the TREE_LIST element.
5195 But the constant could also be an array. Then FIELD is zero.
5197 There is always a maximum of one element in the chain LINK for unions
5198 (even if the initializer in a source program incorrectly contains
5199 more one). */
5201 if (TREE_CODE (local.type) == RECORD_TYPE)
5202 local.field = TYPE_FIELDS (local.type);
5203 else
5204 local.field = NULL_TREE;
5206 for (cnt = 0;
5207 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5208 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5210 local.val = ce->value;
5211 local.index = NULL_TREE;
5213 /* The element in a union constructor specifies the proper field
5214 or index. */
5215 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5216 local.field = ce->index;
5218 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5219 local.index = ce->index;
5221 if (local.field && flag_verbose_asm)
5222 fprintf (asm_out_file, "%s %s:\n",
5223 ASM_COMMENT_START,
5224 DECL_NAME (local.field)
5225 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5226 : "<anonymous>");
5228 /* Eliminate the marker that makes a cast not be an lvalue. */
5229 if (local.val != NULL_TREE)
5230 STRIP_NOPS (local.val);
5232 /* Output the current element, using the appropriate helper ... */
5234 /* For an array slice not part of an outer bitfield. */
5235 if (!outer
5236 && local.index != NULL_TREE
5237 && TREE_CODE (local.index) == RANGE_EXPR)
5238 output_constructor_array_range (&local);
5240 /* For a field that is neither a true bitfield nor part of an outer one,
5241 known to be at least byte aligned and multiple-of-bytes long. */
5242 else if (!outer
5243 && (local.field == NULL_TREE
5244 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5245 output_constructor_regular_field (&local);
5247 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5248 supported for scalar fields, so we may need to convert first. */
5249 else
5251 if (TREE_CODE (local.val) == REAL_CST)
5252 local.val
5253 = fold_unary (VIEW_CONVERT_EXPR,
5254 build_nonstandard_integer_type
5255 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5256 local.val);
5257 output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5261 /* If we are not at toplevel, save the pending data for our caller.
5262 Otherwise output the pending data and padding zeros as needed. */
5263 if (outer)
5264 outer->byte = local.byte;
5265 else
5267 if (local.byte_buffer_in_use)
5269 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5270 local.total_bytes++;
5273 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5275 assemble_zeros (local.size - local.total_bytes);
5276 local.total_bytes = local.size;
5280 return local.total_bytes;
5283 /* Mark DECL as weak. */
5285 static void
5286 mark_weak (tree decl)
5288 if (DECL_WEAK (decl))
5289 return;
5291 struct symtab_node *n = symtab_node::get (decl);
5292 if (n && n->refuse_visibility_changes)
5293 error ("%+D declared weak after being used", decl);
5294 DECL_WEAK (decl) = 1;
5296 if (DECL_RTL_SET_P (decl)
5297 && MEM_P (DECL_RTL (decl))
5298 && XEXP (DECL_RTL (decl), 0)
5299 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5300 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5303 /* Merge weak status between NEWDECL and OLDDECL. */
5305 void
5306 merge_weak (tree newdecl, tree olddecl)
5308 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5310 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5312 tree *pwd;
5313 /* We put the NEWDECL on the weak_decls list at some point
5314 and OLDDECL as well. Keep just OLDDECL on the list. */
5315 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5316 if (TREE_VALUE (*pwd) == newdecl)
5318 *pwd = TREE_CHAIN (*pwd);
5319 break;
5322 return;
5325 if (DECL_WEAK (newdecl))
5327 tree wd;
5329 /* NEWDECL is weak, but OLDDECL is not. */
5331 /* If we already output the OLDDECL, we're in trouble; we can't
5332 go back and make it weak. This should never happen in
5333 unit-at-a-time compilation. */
5334 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5336 /* If we've already generated rtl referencing OLDDECL, we may
5337 have done so in a way that will not function properly with
5338 a weak symbol. Again in unit-at-a-time this should be
5339 impossible. */
5340 gcc_assert (!TREE_USED (olddecl)
5341 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5343 if (TARGET_SUPPORTS_WEAK)
5345 /* We put the NEWDECL on the weak_decls list at some point.
5346 Replace it with the OLDDECL. */
5347 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5348 if (TREE_VALUE (wd) == newdecl)
5350 TREE_VALUE (wd) = olddecl;
5351 break;
5353 /* We may not find the entry on the list. If NEWDECL is a
5354 weak alias, then we will have already called
5355 globalize_decl to remove the entry; in that case, we do
5356 not need to do anything. */
5359 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5360 mark_weak (olddecl);
5362 else
5363 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5364 weak. Just update NEWDECL to indicate that it's weak too. */
5365 mark_weak (newdecl);
5368 /* Declare DECL to be a weak symbol. */
5370 void
5371 declare_weak (tree decl)
5373 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5374 if (! TREE_PUBLIC (decl))
5375 error ("weak declaration of %q+D must be public", decl);
5376 else if (!TARGET_SUPPORTS_WEAK)
5377 warning (0, "weak declaration of %q+D not supported", decl);
5379 mark_weak (decl);
5380 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5381 DECL_ATTRIBUTES (decl)
5382 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5385 static void
5386 weak_finish_1 (tree decl)
5388 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5389 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5390 #endif
5392 if (! TREE_USED (decl))
5393 return;
5395 #ifdef ASM_WEAKEN_DECL
5396 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5397 #else
5398 #ifdef ASM_WEAKEN_LABEL
5399 ASM_WEAKEN_LABEL (asm_out_file, name);
5400 #else
5401 #ifdef ASM_OUTPUT_WEAK_ALIAS
5403 static bool warn_once = 0;
5404 if (! warn_once)
5406 warning (0, "only weak aliases are supported in this configuration");
5407 warn_once = 1;
5409 return;
5411 #endif
5412 #endif
5413 #endif
5416 /* Fiven an assembly name, find the decl it is associated with. */
5417 static tree
5418 find_decl (tree target)
5420 symtab_node *node = symtab_node::get_for_asmname (target);
5421 if (node)
5422 return node->decl;
5423 return NULL_TREE;
5426 /* This TREE_LIST contains weakref targets. */
5428 static GTY(()) tree weakref_targets;
5430 /* Emit any pending weak declarations. */
5432 void
5433 weak_finish (void)
5435 tree t;
5437 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5439 tree alias_decl = TREE_PURPOSE (t);
5440 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5442 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5443 /* Remove alias_decl from the weak list, but leave entries for
5444 the target alone. */
5445 target = NULL_TREE;
5446 #ifndef ASM_OUTPUT_WEAKREF
5447 else if (! TREE_SYMBOL_REFERENCED (target))
5449 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5450 defined, otherwise we and weak_finish_1 would use
5451 different macros. */
5452 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5453 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5454 # else
5455 tree decl = find_decl (target);
5457 if (! decl)
5459 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5460 TREE_CODE (alias_decl), target,
5461 TREE_TYPE (alias_decl));
5463 DECL_EXTERNAL (decl) = 1;
5464 TREE_PUBLIC (decl) = 1;
5465 DECL_ARTIFICIAL (decl) = 1;
5466 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5467 TREE_USED (decl) = 1;
5470 weak_finish_1 (decl);
5471 # endif
5473 #endif
5476 tree *p;
5477 tree t2;
5479 /* Remove the alias and the target from the pending weak list
5480 so that we do not emit any .weak directives for the former,
5481 nor multiple .weak directives for the latter. */
5482 for (p = &weak_decls; (t2 = *p) ; )
5484 if (TREE_VALUE (t2) == alias_decl
5485 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5486 *p = TREE_CHAIN (t2);
5487 else
5488 p = &TREE_CHAIN (t2);
5491 /* Remove other weakrefs to the same target, to speed things up. */
5492 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5494 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5495 *p = TREE_CHAIN (t2);
5496 else
5497 p = &TREE_CHAIN (t2);
5502 for (t = weak_decls; t; t = TREE_CHAIN (t))
5504 tree decl = TREE_VALUE (t);
5506 weak_finish_1 (decl);
5510 /* Emit the assembly bits to indicate that DECL is globally visible. */
5512 static void
5513 globalize_decl (tree decl)
5516 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5517 if (DECL_WEAK (decl))
5519 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5520 tree *p, t;
5522 #ifdef ASM_WEAKEN_DECL
5523 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5524 #else
5525 ASM_WEAKEN_LABEL (asm_out_file, name);
5526 #endif
5528 /* Remove this function from the pending weak list so that
5529 we do not emit multiple .weak directives for it. */
5530 for (p = &weak_decls; (t = *p) ; )
5532 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5533 *p = TREE_CHAIN (t);
5534 else
5535 p = &TREE_CHAIN (t);
5538 /* Remove weakrefs to the same target from the pending weakref
5539 list, for the same reason. */
5540 for (p = &weakref_targets; (t = *p) ; )
5542 if (DECL_ASSEMBLER_NAME (decl)
5543 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5544 *p = TREE_CHAIN (t);
5545 else
5546 p = &TREE_CHAIN (t);
5549 return;
5551 #endif
5553 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5556 vec<alias_pair, va_gc> *alias_pairs;
5558 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5559 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5560 tree node is DECL to have the value of the tree node TARGET. */
5562 void
5563 do_assemble_alias (tree decl, tree target)
5565 tree id;
5567 /* Emulated TLS had better not get this var. */
5568 gcc_assert (!(!targetm.have_tls
5569 && TREE_CODE (decl) == VAR_DECL
5570 && DECL_THREAD_LOCAL_P (decl)));
5572 if (TREE_ASM_WRITTEN (decl))
5573 return;
5575 id = DECL_ASSEMBLER_NAME (decl);
5576 ultimate_transparent_alias_target (&id);
5578 /* We must force creation of DECL_RTL for debug info generation, even though
5579 we don't use it here. */
5580 make_decl_rtl (decl);
5582 TREE_ASM_WRITTEN (decl) = 1;
5583 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5584 TREE_ASM_WRITTEN (id) = 1;
5586 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5588 ultimate_transparent_alias_target (&target);
5590 if (!TREE_SYMBOL_REFERENCED (target))
5591 weakref_targets = tree_cons (decl, target, weakref_targets);
5593 #ifdef ASM_OUTPUT_WEAKREF
5594 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5595 IDENTIFIER_POINTER (id),
5596 IDENTIFIER_POINTER (target));
5597 #else
5598 if (!TARGET_SUPPORTS_WEAK)
5600 error_at (DECL_SOURCE_LOCATION (decl),
5601 "weakref is not supported in this configuration");
5602 return;
5604 #endif
5605 return;
5608 #ifdef ASM_OUTPUT_DEF
5609 tree orig_decl = decl;
5611 if (TREE_CODE (decl) == FUNCTION_DECL
5612 && cgraph_node::get (decl)->instrumentation_clone
5613 && cgraph_node::get (decl)->instrumented_version)
5614 orig_decl = cgraph_node::get (decl)->instrumented_version->decl;
5616 /* Make name accessible from other files, if appropriate. */
5618 if (TREE_PUBLIC (decl) || TREE_PUBLIC (orig_decl))
5620 globalize_decl (decl);
5621 maybe_assemble_visibility (decl);
5623 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5625 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5626 if (targetm.has_ifunc_p ())
5627 ASM_OUTPUT_TYPE_DIRECTIVE
5628 (asm_out_file, IDENTIFIER_POINTER (id),
5629 IFUNC_ASM_TYPE);
5630 else
5631 #endif
5632 error_at (DECL_SOURCE_LOCATION (decl),
5633 "ifunc is not supported on this target");
5636 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5637 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5638 # else
5639 ASM_OUTPUT_DEF (asm_out_file,
5640 IDENTIFIER_POINTER (id),
5641 IDENTIFIER_POINTER (target));
5642 # endif
5643 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5645 const char *name;
5646 tree *p, t;
5648 name = IDENTIFIER_POINTER (id);
5649 # ifdef ASM_WEAKEN_DECL
5650 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5651 # else
5652 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5653 # endif
5654 /* Remove this function from the pending weak list so that
5655 we do not emit multiple .weak directives for it. */
5656 for (p = &weak_decls; (t = *p) ; )
5657 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t))
5658 || id == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5659 *p = TREE_CHAIN (t);
5660 else
5661 p = &TREE_CHAIN (t);
5663 /* Remove weakrefs to the same target from the pending weakref
5664 list, for the same reason. */
5665 for (p = &weakref_targets; (t = *p) ; )
5667 if (id == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5668 *p = TREE_CHAIN (t);
5669 else
5670 p = &TREE_CHAIN (t);
5673 #endif
5676 /* Emit an assembler directive to make the symbol for DECL an alias to
5677 the symbol for TARGET. */
5679 void
5680 assemble_alias (tree decl, tree target)
5682 tree target_decl;
5684 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5686 tree alias = DECL_ASSEMBLER_NAME (decl);
5688 ultimate_transparent_alias_target (&target);
5690 if (alias == target)
5691 error ("weakref %q+D ultimately targets itself", decl);
5692 if (TREE_PUBLIC (decl))
5693 error ("weakref %q+D must have static linkage", decl);
5695 else
5697 #if !defined (ASM_OUTPUT_DEF)
5698 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5699 error_at (DECL_SOURCE_LOCATION (decl),
5700 "alias definitions not supported in this configuration");
5701 TREE_ASM_WRITTEN (decl) = 1;
5702 return;
5703 # else
5704 if (!DECL_WEAK (decl))
5706 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5707 error_at (DECL_SOURCE_LOCATION (decl),
5708 "ifunc is not supported in this configuration");
5709 else
5710 error_at (DECL_SOURCE_LOCATION (decl),
5711 "only weak aliases are supported in this configuration");
5712 TREE_ASM_WRITTEN (decl) = 1;
5713 return;
5715 # endif
5716 #endif
5718 TREE_USED (decl) = 1;
5720 /* Allow aliases to aliases. */
5721 if (TREE_CODE (decl) == FUNCTION_DECL)
5722 cgraph_node::get_create (decl)->alias = true;
5723 else
5724 varpool_node::get_create (decl)->alias = true;
5726 /* If the target has already been emitted, we don't have to queue the
5727 alias. This saves a tad of memory. */
5728 if (symtab->global_info_ready)
5729 target_decl = find_decl (target);
5730 else
5731 target_decl= NULL;
5732 if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5733 || symtab->state >= EXPANSION)
5734 do_assemble_alias (decl, target);
5735 else
5737 alias_pair p = {decl, target};
5738 vec_safe_push (alias_pairs, p);
5742 /* Record and output a table of translations from original function
5743 to its transaction aware clone. Note that tm_pure functions are
5744 considered to be their own clone. */
5746 struct tm_clone_hasher : ggc_cache_hasher<tree_map *>
5748 static hashval_t hash (tree_map *m) { return tree_map_hash (m); }
5749 static bool equal (tree_map *a, tree_map *b) { return tree_map_eq (a, b); }
5751 static void handle_cache_entry (tree_map *&e)
5753 if (e != HTAB_EMPTY_ENTRY || e != HTAB_DELETED_ENTRY)
5755 extern void gt_ggc_mx (tree_map *&);
5756 if (ggc_marked_p (e->base.from))
5757 gt_ggc_mx (e);
5758 else
5759 e = static_cast<tree_map *> (HTAB_DELETED_ENTRY);
5764 static GTY((cache))
5765 hash_table<tm_clone_hasher> *tm_clone_hash;
5767 void
5768 record_tm_clone_pair (tree o, tree n)
5770 struct tree_map **slot, *h;
5772 if (tm_clone_hash == NULL)
5773 tm_clone_hash = hash_table<tm_clone_hasher>::create_ggc (32);
5775 h = ggc_alloc<tree_map> ();
5776 h->hash = htab_hash_pointer (o);
5777 h->base.from = o;
5778 h->to = n;
5780 slot = tm_clone_hash->find_slot_with_hash (h, h->hash, INSERT);
5781 *slot = h;
5784 tree
5785 get_tm_clone_pair (tree o)
5787 if (tm_clone_hash)
5789 struct tree_map *h, in;
5791 in.base.from = o;
5792 in.hash = htab_hash_pointer (o);
5793 h = tm_clone_hash->find_with_hash (&in, in.hash);
5794 if (h)
5795 return h->to;
5797 return NULL_TREE;
5800 typedef struct tm_alias_pair
5802 unsigned int uid;
5803 tree from;
5804 tree to;
5805 } tm_alias_pair;
5808 /* Dump the actual pairs to the .tm_clone_table section. */
5810 static void
5811 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
5813 unsigned i;
5814 tm_alias_pair *p;
5815 bool switched = false;
5817 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
5819 tree src = p->from;
5820 tree dst = p->to;
5821 struct cgraph_node *src_n = cgraph_node::get (src);
5822 struct cgraph_node *dst_n = cgraph_node::get (dst);
5824 /* The function ipa_tm_create_version() marks the clone as needed if
5825 the original function was needed. But we also mark the clone as
5826 needed if we ever called the clone indirectly through
5827 TM_GETTMCLONE. If neither of these are true, we didn't generate
5828 a clone, and we didn't call it indirectly... no sense keeping it
5829 in the clone table. */
5830 if (!dst_n || !dst_n->definition)
5831 continue;
5833 /* This covers the case where we have optimized the original
5834 function away, and only access the transactional clone. */
5835 if (!src_n || !src_n->definition)
5836 continue;
5838 if (!switched)
5840 switch_to_section (targetm.asm_out.tm_clone_table_section ());
5841 assemble_align (POINTER_SIZE);
5842 switched = true;
5845 assemble_integer (XEXP (DECL_RTL (src), 0),
5846 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
5847 assemble_integer (XEXP (DECL_RTL (dst), 0),
5848 POINTER_SIZE_UNITS, POINTER_SIZE, 1);
5852 /* Provide a default for the tm_clone_table section. */
5854 section *
5855 default_clone_table_section (void)
5857 return get_named_section (NULL, ".tm_clone_table", 3);
5860 /* Helper comparison function for qsorting by the DECL_UID stored in
5861 alias_pair->emitted_diags. */
5863 static int
5864 tm_alias_pair_cmp (const void *x, const void *y)
5866 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
5867 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
5868 if (p1->uid < p2->uid)
5869 return -1;
5870 if (p1->uid > p2->uid)
5871 return 1;
5872 return 0;
5875 void
5876 finish_tm_clone_pairs (void)
5878 vec<tm_alias_pair> tm_alias_pairs = vNULL;
5880 if (tm_clone_hash == NULL)
5881 return;
5883 /* We need a determenistic order for the .tm_clone_table, otherwise
5884 we will get bootstrap comparison failures, so dump the hash table
5885 to a vector, sort it, and dump the vector. */
5887 /* Dump the hashtable to a vector. */
5888 tree_map *map;
5889 hash_table<tm_clone_hasher>::iterator iter;
5890 FOR_EACH_HASH_TABLE_ELEMENT (*tm_clone_hash, map, tree_map *, iter)
5892 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
5893 tm_alias_pairs.safe_push (p);
5895 /* Sort it. */
5896 tm_alias_pairs.qsort (tm_alias_pair_cmp);
5898 /* Dump it. */
5899 dump_tm_clone_pairs (tm_alias_pairs);
5901 tm_clone_hash->empty ();
5902 tm_clone_hash = NULL;
5903 tm_alias_pairs.release ();
5907 /* Emit an assembler directive to set symbol for DECL visibility to
5908 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
5910 void
5911 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
5912 int vis ATTRIBUTE_UNUSED)
5914 #ifdef HAVE_GAS_HIDDEN
5915 static const char * const visibility_types[] = {
5916 NULL, "protected", "hidden", "internal"
5919 const char *name, *type;
5921 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5922 type = visibility_types[vis];
5924 fprintf (asm_out_file, "\t.%s\t", type);
5925 assemble_name (asm_out_file, name);
5926 fprintf (asm_out_file, "\n");
5927 #else
5928 if (!DECL_ARTIFICIAL (decl))
5929 warning (OPT_Wattributes, "visibility attribute not supported "
5930 "in this configuration; ignored");
5931 #endif
5934 /* A helper function to call assemble_visibility when needed for a decl. */
5937 maybe_assemble_visibility (tree decl)
5939 enum symbol_visibility vis = DECL_VISIBILITY (decl);
5941 if (TREE_CODE (decl) == FUNCTION_DECL
5942 && cgraph_node::get (decl)
5943 && cgraph_node::get (decl)->instrumentation_clone
5944 && cgraph_node::get (decl)->instrumented_version)
5945 vis = DECL_VISIBILITY (cgraph_node::get (decl)->instrumented_version->decl);
5947 if (vis != VISIBILITY_DEFAULT)
5949 targetm.asm_out.assemble_visibility (decl, vis);
5950 return 1;
5952 else
5953 return 0;
5956 /* Returns 1 if the target configuration supports defining public symbols
5957 so that one of them will be chosen at link time instead of generating a
5958 multiply-defined symbol error, whether through the use of weak symbols or
5959 a target-specific mechanism for having duplicates discarded. */
5962 supports_one_only (void)
5964 if (SUPPORTS_ONE_ONLY)
5965 return 1;
5966 return TARGET_SUPPORTS_WEAK;
5969 /* Set up DECL as a public symbol that can be defined in multiple
5970 translation units without generating a linker error. */
5972 void
5973 make_decl_one_only (tree decl, tree comdat_group)
5975 struct symtab_node *symbol;
5976 gcc_assert (TREE_CODE (decl) == VAR_DECL
5977 || TREE_CODE (decl) == FUNCTION_DECL);
5979 TREE_PUBLIC (decl) = 1;
5981 if (TREE_CODE (decl) == VAR_DECL)
5982 symbol = varpool_node::get_create (decl);
5983 else
5984 symbol = cgraph_node::get_create (decl);
5986 if (SUPPORTS_ONE_ONLY)
5988 #ifdef MAKE_DECL_ONE_ONLY
5989 MAKE_DECL_ONE_ONLY (decl);
5990 #endif
5991 symbol->set_comdat_group (comdat_group);
5993 else if (TREE_CODE (decl) == VAR_DECL
5994 && (DECL_INITIAL (decl) == 0
5995 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
5996 DECL_COMMON (decl) = 1;
5997 else
5999 gcc_assert (TARGET_SUPPORTS_WEAK);
6000 DECL_WEAK (decl) = 1;
6004 void
6005 init_varasm_once (void)
6007 section_htab = hash_table<section_hasher>::create_ggc (31);
6008 object_block_htab = hash_table<object_block_hasher>::create_ggc (31);
6009 const_desc_htab = hash_table<tree_descriptor_hasher>::create_ggc (1009);
6011 shared_constant_pool = create_constant_pool ();
6013 #ifdef TEXT_SECTION_ASM_OP
6014 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
6015 TEXT_SECTION_ASM_OP);
6016 #endif
6018 #ifdef DATA_SECTION_ASM_OP
6019 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
6020 DATA_SECTION_ASM_OP);
6021 #endif
6023 #ifdef SDATA_SECTION_ASM_OP
6024 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
6025 SDATA_SECTION_ASM_OP);
6026 #endif
6028 #ifdef READONLY_DATA_SECTION_ASM_OP
6029 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
6030 READONLY_DATA_SECTION_ASM_OP);
6031 #endif
6033 #ifdef CTORS_SECTION_ASM_OP
6034 ctors_section = get_unnamed_section (0, output_section_asm_op,
6035 CTORS_SECTION_ASM_OP);
6036 #endif
6038 #ifdef DTORS_SECTION_ASM_OP
6039 dtors_section = get_unnamed_section (0, output_section_asm_op,
6040 DTORS_SECTION_ASM_OP);
6041 #endif
6043 #ifdef BSS_SECTION_ASM_OP
6044 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6045 output_section_asm_op,
6046 BSS_SECTION_ASM_OP);
6047 #endif
6049 #ifdef SBSS_SECTION_ASM_OP
6050 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6051 output_section_asm_op,
6052 SBSS_SECTION_ASM_OP);
6053 #endif
6055 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6056 | SECTION_COMMON, emit_tls_common);
6057 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6058 | SECTION_COMMON, emit_local);
6059 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6060 | SECTION_COMMON, emit_common);
6062 #if defined ASM_OUTPUT_ALIGNED_BSS
6063 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
6064 emit_bss);
6065 #endif
6067 targetm.asm_out.init_sections ();
6069 if (readonly_data_section == NULL)
6070 readonly_data_section = text_section;
6072 #ifdef ASM_OUTPUT_EXTERNAL
6073 pending_assemble_externals_set = new hash_set<tree>;
6074 #endif
6077 enum tls_model
6078 decl_default_tls_model (const_tree decl)
6080 enum tls_model kind;
6081 bool is_local;
6083 is_local = targetm.binds_local_p (decl);
6084 if (!flag_shlib)
6086 if (is_local)
6087 kind = TLS_MODEL_LOCAL_EXEC;
6088 else
6089 kind = TLS_MODEL_INITIAL_EXEC;
6092 /* Local dynamic is inefficient when we're not combining the
6093 parts of the address. */
6094 else if (optimize && is_local)
6095 kind = TLS_MODEL_LOCAL_DYNAMIC;
6096 else
6097 kind = TLS_MODEL_GLOBAL_DYNAMIC;
6098 if (kind < flag_tls_default)
6099 kind = flag_tls_default;
6101 return kind;
6104 /* Select a set of attributes for section NAME based on the properties
6105 of DECL and whether or not RELOC indicates that DECL's initializer
6106 might contain runtime relocations.
6108 We make the section read-only and executable for a function decl,
6109 read-only for a const data decl, and writable for a non-const data decl. */
6111 unsigned int
6112 default_section_type_flags (tree decl, const char *name, int reloc)
6114 unsigned int flags;
6116 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6117 flags = SECTION_CODE;
6118 else if (decl)
6120 enum section_category category
6121 = categorize_decl_for_section (decl, reloc);
6122 if (decl_readonly_section_1 (category))
6123 flags = 0;
6124 else if (category == SECCAT_DATA_REL_RO
6125 || category == SECCAT_DATA_REL_RO_LOCAL)
6126 flags = SECTION_WRITE | SECTION_RELRO;
6127 else
6128 flags = SECTION_WRITE;
6130 else
6132 flags = SECTION_WRITE;
6133 if (strcmp (name, ".data.rel.ro") == 0
6134 || strcmp (name, ".data.rel.ro.local") == 0)
6135 flags |= SECTION_RELRO;
6138 if (decl && DECL_P (decl) && DECL_COMDAT_GROUP (decl))
6139 flags |= SECTION_LINKONCE;
6141 if (strcmp (name, ".vtable_map_vars") == 0)
6142 flags |= SECTION_LINKONCE;
6144 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6145 flags |= SECTION_TLS | SECTION_WRITE;
6147 if (strcmp (name, ".bss") == 0
6148 || strncmp (name, ".bss.", 5) == 0
6149 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6150 || strcmp (name, ".persistent.bss") == 0
6151 || strcmp (name, ".sbss") == 0
6152 || strncmp (name, ".sbss.", 6) == 0
6153 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6154 flags |= SECTION_BSS;
6156 if (strcmp (name, ".tdata") == 0
6157 || strncmp (name, ".tdata.", 7) == 0
6158 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6159 flags |= SECTION_TLS;
6161 if (strcmp (name, ".tbss") == 0
6162 || strncmp (name, ".tbss.", 6) == 0
6163 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6164 flags |= SECTION_TLS | SECTION_BSS;
6166 /* These three sections have special ELF types. They are neither
6167 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
6168 want to print a section type (@progbits or @nobits). If someone
6169 is silly enough to emit code or TLS variables to one of these
6170 sections, then don't handle them specially. */
6171 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6172 && (strcmp (name, ".init_array") == 0
6173 || strcmp (name, ".fini_array") == 0
6174 || strcmp (name, ".preinit_array") == 0))
6175 flags |= SECTION_NOTYPE;
6177 return flags;
6180 /* Return true if the target supports some form of global BSS,
6181 either through bss_noswitch_section, or by selecting a BSS
6182 section in TARGET_ASM_SELECT_SECTION. */
6184 bool
6185 have_global_bss_p (void)
6187 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6190 /* Output assembly to switch to section NAME with attribute FLAGS.
6191 Four variants for common object file formats. */
6193 void
6194 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6195 unsigned int flags ATTRIBUTE_UNUSED,
6196 tree decl ATTRIBUTE_UNUSED)
6198 /* Some object formats don't support named sections at all. The
6199 front-end should already have flagged this as an error. */
6200 gcc_unreachable ();
6203 #ifndef TLS_SECTION_ASM_FLAG
6204 #define TLS_SECTION_ASM_FLAG 'T'
6205 #endif
6207 void
6208 default_elf_asm_named_section (const char *name, unsigned int flags,
6209 tree decl ATTRIBUTE_UNUSED)
6211 char flagchars[10], *f = flagchars;
6213 /* If we have already declared this section, we can use an
6214 abbreviated form to switch back to it -- unless this section is
6215 part of a COMDAT groups, in which case GAS requires the full
6216 declaration every time. */
6217 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6218 && (flags & SECTION_DECLARED))
6220 fprintf (asm_out_file, "\t.section\t%s\n", name);
6221 return;
6224 if (!(flags & SECTION_DEBUG))
6225 *f++ = 'a';
6226 #if defined (HAVE_GAS_SECTION_EXCLUDE) && HAVE_GAS_SECTION_EXCLUDE == 1
6227 if (flags & SECTION_EXCLUDE)
6228 *f++ = 'e';
6229 #endif
6230 if (flags & SECTION_WRITE)
6231 *f++ = 'w';
6232 if (flags & SECTION_CODE)
6233 *f++ = 'x';
6234 if (flags & SECTION_SMALL)
6235 *f++ = 's';
6236 if (flags & SECTION_MERGE)
6237 *f++ = 'M';
6238 if (flags & SECTION_STRINGS)
6239 *f++ = 'S';
6240 if (flags & SECTION_TLS)
6241 *f++ = TLS_SECTION_ASM_FLAG;
6242 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6243 *f++ = 'G';
6244 *f = '\0';
6246 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6248 if (!(flags & SECTION_NOTYPE))
6250 const char *type;
6251 const char *format;
6253 if (flags & SECTION_BSS)
6254 type = "nobits";
6255 else
6256 type = "progbits";
6258 format = ",@%s";
6259 /* On platforms that use "@" as the assembly comment character,
6260 use "%" instead. */
6261 if (strcmp (ASM_COMMENT_START, "@") == 0)
6262 format = ",%%%s";
6263 fprintf (asm_out_file, format, type);
6265 if (flags & SECTION_ENTSIZE)
6266 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6267 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6269 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6270 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6271 else
6272 fprintf (asm_out_file, ",%s,comdat",
6273 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6277 putc ('\n', asm_out_file);
6280 void
6281 default_coff_asm_named_section (const char *name, unsigned int flags,
6282 tree decl ATTRIBUTE_UNUSED)
6284 char flagchars[8], *f = flagchars;
6286 if (flags & SECTION_WRITE)
6287 *f++ = 'w';
6288 if (flags & SECTION_CODE)
6289 *f++ = 'x';
6290 *f = '\0';
6292 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6295 void
6296 default_pe_asm_named_section (const char *name, unsigned int flags,
6297 tree decl)
6299 default_coff_asm_named_section (name, flags, decl);
6301 if (flags & SECTION_LINKONCE)
6303 /* Functions may have been compiled at various levels of
6304 optimization so we can't use `same_size' here.
6305 Instead, have the linker pick one. */
6306 fprintf (asm_out_file, "\t.linkonce %s\n",
6307 (flags & SECTION_CODE ? "discard" : "same_size"));
6311 /* The lame default section selector. */
6313 section *
6314 default_select_section (tree decl, int reloc,
6315 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6317 if (DECL_P (decl))
6319 if (decl_readonly_section (decl, reloc))
6320 return readonly_data_section;
6322 else if (TREE_CODE (decl) == CONSTRUCTOR)
6324 if (! ((flag_pic && reloc)
6325 || !TREE_READONLY (decl)
6326 || TREE_SIDE_EFFECTS (decl)
6327 || !TREE_CONSTANT (decl)))
6328 return readonly_data_section;
6330 else if (TREE_CODE (decl) == STRING_CST)
6331 return readonly_data_section;
6332 else if (! (flag_pic && reloc))
6333 return readonly_data_section;
6335 return data_section;
6338 enum section_category
6339 categorize_decl_for_section (const_tree decl, int reloc)
6341 enum section_category ret;
6343 if (TREE_CODE (decl) == FUNCTION_DECL)
6344 return SECCAT_TEXT;
6345 else if (TREE_CODE (decl) == STRING_CST)
6347 if ((flag_sanitize & SANITIZE_ADDRESS)
6348 && asan_protect_global (CONST_CAST_TREE (decl)))
6349 /* or !flag_merge_constants */
6350 return SECCAT_RODATA;
6351 else
6352 return SECCAT_RODATA_MERGE_STR;
6354 else if (TREE_CODE (decl) == VAR_DECL)
6356 if (bss_initializer_p (decl))
6357 ret = SECCAT_BSS;
6358 else if (! TREE_READONLY (decl)
6359 || TREE_SIDE_EFFECTS (decl)
6360 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
6362 /* Here the reloc_rw_mask is not testing whether the section should
6363 be read-only or not, but whether the dynamic link will have to
6364 do something. If so, we wish to segregate the data in order to
6365 minimize cache misses inside the dynamic linker. */
6366 if (reloc & targetm.asm_out.reloc_rw_mask ())
6367 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6368 else
6369 ret = SECCAT_DATA;
6371 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6372 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6373 else if (reloc || flag_merge_constants < 2
6374 || ((flag_sanitize & SANITIZE_ADDRESS)
6375 && asan_protect_global (CONST_CAST_TREE (decl))))
6376 /* C and C++ don't allow different variables to share the same
6377 location. -fmerge-all-constants allows even that (at the
6378 expense of not conforming). */
6379 ret = SECCAT_RODATA;
6380 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6381 ret = SECCAT_RODATA_MERGE_STR_INIT;
6382 else
6383 ret = SECCAT_RODATA_MERGE_CONST;
6385 else if (TREE_CODE (decl) == CONSTRUCTOR)
6387 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6388 || TREE_SIDE_EFFECTS (decl)
6389 || ! TREE_CONSTANT (decl))
6390 ret = SECCAT_DATA;
6391 else
6392 ret = SECCAT_RODATA;
6394 else
6395 ret = SECCAT_RODATA;
6397 /* There are no read-only thread-local sections. */
6398 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6400 /* Note that this would be *just* SECCAT_BSS, except that there's
6401 no concept of a read-only thread-local-data section. */
6402 if (ret == SECCAT_BSS
6403 || (flag_zero_initialized_in_bss
6404 && initializer_zerop (DECL_INITIAL (decl))))
6405 ret = SECCAT_TBSS;
6406 else
6407 ret = SECCAT_TDATA;
6410 /* If the target uses small data sections, select it. */
6411 else if (targetm.in_small_data_p (decl))
6413 if (ret == SECCAT_BSS)
6414 ret = SECCAT_SBSS;
6415 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6416 ret = SECCAT_SRODATA;
6417 else
6418 ret = SECCAT_SDATA;
6421 return ret;
6424 static bool
6425 decl_readonly_section_1 (enum section_category category)
6427 switch (category)
6429 case SECCAT_RODATA:
6430 case SECCAT_RODATA_MERGE_STR:
6431 case SECCAT_RODATA_MERGE_STR_INIT:
6432 case SECCAT_RODATA_MERGE_CONST:
6433 case SECCAT_SRODATA:
6434 return true;
6435 default:
6436 return false;
6440 bool
6441 decl_readonly_section (const_tree decl, int reloc)
6443 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6446 /* Select a section based on the above categorization. */
6448 section *
6449 default_elf_select_section (tree decl, int reloc,
6450 unsigned HOST_WIDE_INT align)
6452 const char *sname;
6453 switch (categorize_decl_for_section (decl, reloc))
6455 case SECCAT_TEXT:
6456 /* We're not supposed to be called on FUNCTION_DECLs. */
6457 gcc_unreachable ();
6458 case SECCAT_RODATA:
6459 return readonly_data_section;
6460 case SECCAT_RODATA_MERGE_STR:
6461 return mergeable_string_section (decl, align, 0);
6462 case SECCAT_RODATA_MERGE_STR_INIT:
6463 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6464 case SECCAT_RODATA_MERGE_CONST:
6465 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6466 case SECCAT_SRODATA:
6467 sname = ".sdata2";
6468 break;
6469 case SECCAT_DATA:
6470 return data_section;
6471 case SECCAT_DATA_REL:
6472 sname = ".data.rel";
6473 break;
6474 case SECCAT_DATA_REL_LOCAL:
6475 sname = ".data.rel.local";
6476 break;
6477 case SECCAT_DATA_REL_RO:
6478 sname = ".data.rel.ro";
6479 break;
6480 case SECCAT_DATA_REL_RO_LOCAL:
6481 sname = ".data.rel.ro.local";
6482 break;
6483 case SECCAT_SDATA:
6484 sname = ".sdata";
6485 break;
6486 case SECCAT_TDATA:
6487 sname = ".tdata";
6488 break;
6489 case SECCAT_BSS:
6490 if (bss_section)
6491 return bss_section;
6492 sname = ".bss";
6493 break;
6494 case SECCAT_SBSS:
6495 sname = ".sbss";
6496 break;
6497 case SECCAT_TBSS:
6498 sname = ".tbss";
6499 break;
6500 default:
6501 gcc_unreachable ();
6504 return get_named_section (decl, sname, reloc);
6507 /* Construct a unique section name based on the decl name and the
6508 categorization performed above. */
6510 void
6511 default_unique_section (tree decl, int reloc)
6513 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6514 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6515 const char *prefix, *name, *linkonce;
6516 char *string;
6517 tree id;
6519 switch (categorize_decl_for_section (decl, reloc))
6521 case SECCAT_TEXT:
6522 prefix = one_only ? ".t" : ".text";
6523 break;
6524 case SECCAT_RODATA:
6525 case SECCAT_RODATA_MERGE_STR:
6526 case SECCAT_RODATA_MERGE_STR_INIT:
6527 case SECCAT_RODATA_MERGE_CONST:
6528 prefix = one_only ? ".r" : ".rodata";
6529 break;
6530 case SECCAT_SRODATA:
6531 prefix = one_only ? ".s2" : ".sdata2";
6532 break;
6533 case SECCAT_DATA:
6534 prefix = one_only ? ".d" : ".data";
6535 break;
6536 case SECCAT_DATA_REL:
6537 prefix = one_only ? ".d.rel" : ".data.rel";
6538 break;
6539 case SECCAT_DATA_REL_LOCAL:
6540 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6541 break;
6542 case SECCAT_DATA_REL_RO:
6543 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6544 break;
6545 case SECCAT_DATA_REL_RO_LOCAL:
6546 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6547 break;
6548 case SECCAT_SDATA:
6549 prefix = one_only ? ".s" : ".sdata";
6550 break;
6551 case SECCAT_BSS:
6552 prefix = one_only ? ".b" : ".bss";
6553 break;
6554 case SECCAT_SBSS:
6555 prefix = one_only ? ".sb" : ".sbss";
6556 break;
6557 case SECCAT_TDATA:
6558 prefix = one_only ? ".td" : ".tdata";
6559 break;
6560 case SECCAT_TBSS:
6561 prefix = one_only ? ".tb" : ".tbss";
6562 break;
6563 default:
6564 gcc_unreachable ();
6567 id = DECL_ASSEMBLER_NAME (decl);
6568 ultimate_transparent_alias_target (&id);
6569 name = IDENTIFIER_POINTER (id);
6570 name = targetm.strip_name_encoding (name);
6572 /* If we're using one_only, then there needs to be a .gnu.linkonce
6573 prefix to the section name. */
6574 linkonce = one_only ? ".gnu.linkonce" : "";
6576 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6578 set_decl_section_name (decl, string);
6581 /* Subroutine of compute_reloc_for_rtx for leaf rtxes. */
6583 static int
6584 compute_reloc_for_rtx_1 (const_rtx x)
6586 switch (GET_CODE (x))
6588 case SYMBOL_REF:
6589 return SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6590 case LABEL_REF:
6591 return 1;
6592 default:
6593 return 0;
6597 /* Like compute_reloc_for_constant, except for an RTX. The return value
6598 is a mask for which bit 1 indicates a global relocation, and bit 0
6599 indicates a local relocation. */
6601 static int
6602 compute_reloc_for_rtx (const_rtx x)
6604 switch (GET_CODE (x))
6606 case SYMBOL_REF:
6607 case LABEL_REF:
6608 return compute_reloc_for_rtx_1 (x);
6610 case CONST:
6612 int reloc = 0;
6613 subrtx_iterator::array_type array;
6614 FOR_EACH_SUBRTX (iter, array, x, ALL)
6615 reloc |= compute_reloc_for_rtx_1 (*iter);
6616 return reloc;
6619 default:
6620 return 0;
6624 section *
6625 default_select_rtx_section (machine_mode mode ATTRIBUTE_UNUSED,
6626 rtx x,
6627 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6629 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6630 return data_section;
6631 else
6632 return readonly_data_section;
6635 section *
6636 default_elf_select_rtx_section (machine_mode mode, rtx x,
6637 unsigned HOST_WIDE_INT align)
6639 int reloc = compute_reloc_for_rtx (x);
6641 /* ??? Handle small data here somehow. */
6643 if (reloc & targetm.asm_out.reloc_rw_mask ())
6645 if (reloc == 1)
6646 return get_named_section (NULL, ".data.rel.ro.local", 1);
6647 else
6648 return get_named_section (NULL, ".data.rel.ro", 3);
6651 return mergeable_constant_section (mode, align, 0);
6654 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6656 void
6657 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6659 rtx symbol;
6660 int flags;
6662 /* Careful not to prod global register variables. */
6663 if (!MEM_P (rtl))
6664 return;
6665 symbol = XEXP (rtl, 0);
6666 if (GET_CODE (symbol) != SYMBOL_REF)
6667 return;
6669 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6670 if (TREE_CODE (decl) == FUNCTION_DECL)
6671 flags |= SYMBOL_FLAG_FUNCTION;
6672 if (targetm.binds_local_p (decl))
6673 flags |= SYMBOL_FLAG_LOCAL;
6674 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6675 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6676 else if (targetm.in_small_data_p (decl))
6677 flags |= SYMBOL_FLAG_SMALL;
6678 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6679 being PUBLIC, the thing *must* be defined in this translation unit.
6680 Prevent this buglet from being propagated into rtl code as well. */
6681 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6682 flags |= SYMBOL_FLAG_EXTERNAL;
6684 SYMBOL_REF_FLAGS (symbol) = flags;
6687 /* By default, we do nothing for encode_section_info, so we need not
6688 do anything but discard the '*' marker. */
6690 const char *
6691 default_strip_name_encoding (const char *str)
6693 return str + (*str == '*');
6696 #ifdef ASM_OUTPUT_DEF
6697 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6698 anchor relative to ".", the current section position. */
6700 void
6701 default_asm_output_anchor (rtx symbol)
6703 char buffer[100];
6705 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6706 SYMBOL_REF_BLOCK_OFFSET (symbol));
6707 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6709 #endif
6711 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6713 bool
6714 default_use_anchors_for_symbol_p (const_rtx symbol)
6716 section *sect;
6717 tree decl;
6719 /* Don't use anchors for mergeable sections. The linker might move
6720 the objects around. */
6721 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6722 if (sect->common.flags & SECTION_MERGE)
6723 return false;
6725 /* Don't use anchors for small data sections. The small data register
6726 acts as an anchor for such sections. */
6727 if (sect->common.flags & SECTION_SMALL)
6728 return false;
6730 decl = SYMBOL_REF_DECL (symbol);
6731 if (decl && DECL_P (decl))
6733 /* Don't use section anchors for decls that might be defined or
6734 usurped by other modules. */
6735 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6736 return false;
6738 /* Don't use section anchors for decls that will be placed in a
6739 small data section. */
6740 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6741 one above. The problem is that we only use SECTION_SMALL for
6742 sections that should be marked as small in the section directive. */
6743 if (targetm.in_small_data_p (decl))
6744 return false;
6746 return true;
6749 /* Return true when RESOLUTION indicate that symbol will be bound to the
6750 definition provided by current .o file. */
6752 static bool
6753 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
6755 return (resolution == LDPR_PREVAILING_DEF
6756 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6757 || resolution == LDPR_PREVAILING_DEF_IRONLY);
6760 /* Return true when RESOLUTION indicate that symbol will be bound locally
6761 within current executable or DSO. */
6763 static bool
6764 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
6766 return (resolution == LDPR_PREVAILING_DEF
6767 || resolution == LDPR_PREVAILING_DEF_IRONLY
6768 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6769 || resolution == LDPR_PREEMPTED_REG
6770 || resolution == LDPR_PREEMPTED_IR
6771 || resolution == LDPR_RESOLVED_IR
6772 || resolution == LDPR_RESOLVED_EXEC);
6775 /* Assume ELF-ish defaults, since that's pretty much the most liberal
6776 wrt cross-module name binding. */
6778 bool
6779 default_binds_local_p (const_tree exp)
6781 return default_binds_local_p_1 (exp, flag_shlib);
6784 bool
6785 default_binds_local_p_1 (const_tree exp, int shlib)
6787 bool local_p;
6788 bool resolved_locally = false;
6789 bool resolved_to_local_def = false;
6791 /* With resolution file in hands, take look into resolutions.
6792 We can't just return true for resolved_locally symbols,
6793 because dynamic linking might overwrite symbols
6794 in shared libraries. */
6795 if (TREE_CODE (exp) == VAR_DECL && TREE_PUBLIC (exp)
6796 && (TREE_STATIC (exp) || DECL_EXTERNAL (exp)))
6798 varpool_node *vnode = varpool_node::get (exp);
6799 if (vnode && (resolution_local_p (vnode->resolution) || vnode->in_other_partition))
6800 resolved_locally = true;
6801 if (vnode
6802 && resolution_to_local_definition_p (vnode->resolution))
6803 resolved_to_local_def = true;
6805 else if (TREE_CODE (exp) == FUNCTION_DECL && TREE_PUBLIC (exp))
6807 struct cgraph_node *node = cgraph_node::get (exp);
6808 if (node
6809 && (resolution_local_p (node->resolution) || node->in_other_partition))
6810 resolved_locally = true;
6811 if (node
6812 && resolution_to_local_definition_p (node->resolution))
6813 resolved_to_local_def = true;
6816 /* A non-decl is an entry in the constant pool. */
6817 if (!DECL_P (exp))
6818 local_p = true;
6819 /* Weakrefs may not bind locally, even though the weakref itself is always
6820 static and therefore local. Similarly, the resolver for ifunc functions
6821 might resolve to a non-local function.
6822 FIXME: We can resolve the weakref case more curefuly by looking at the
6823 weakref alias. */
6824 else if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
6825 || (TREE_CODE (exp) == FUNCTION_DECL
6826 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
6827 local_p = false;
6828 /* Static variables are always local. */
6829 else if (! TREE_PUBLIC (exp))
6830 local_p = true;
6831 /* A variable is local if the user has said explicitly that it will
6832 be. */
6833 else if ((DECL_VISIBILITY_SPECIFIED (exp)
6834 || resolved_to_local_def)
6835 && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6836 local_p = true;
6837 /* Variables defined outside this object might not be local. */
6838 else if (DECL_EXTERNAL (exp) && !resolved_locally)
6839 local_p = false;
6840 /* If defined in this object and visibility is not default, must be
6841 local. */
6842 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6843 local_p = true;
6844 /* Default visibility weak data can be overridden by a strong symbol
6845 in another module and so are not local. */
6846 else if (DECL_WEAK (exp)
6847 && !resolved_locally)
6848 local_p = false;
6849 /* If PIC, then assume that any global name can be overridden by
6850 symbols resolved from other modules. */
6851 else if (shlib)
6852 local_p = false;
6853 /* Uninitialized COMMON variable may be unified with symbols
6854 resolved from other modules. */
6855 else if (DECL_COMMON (exp)
6856 && !resolved_locally
6857 && (DECL_INITIAL (exp) == NULL
6858 || (!in_lto_p && DECL_INITIAL (exp) == error_mark_node)))
6859 local_p = false;
6860 /* Otherwise we're left with initialized (or non-common) global data
6861 which is of necessity defined locally. */
6862 else
6863 local_p = true;
6865 return local_p;
6868 /* Return true when references to DECL must bind to current definition in
6869 final executable.
6871 The condition is usually equivalent to whether the function binds to the
6872 current module (shared library or executable), that is to binds_local_p.
6873 We use this fact to avoid need for another target hook and implement
6874 the logic using binds_local_p and just special cases where
6875 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
6876 the weak definitions (that can be overwritten at linktime by other
6877 definition from different object file) and when resolution info is available
6878 we simply use the knowledge passed to us by linker plugin. */
6879 bool
6880 decl_binds_to_current_def_p (const_tree decl)
6882 gcc_assert (DECL_P (decl));
6883 if (!targetm.binds_local_p (decl))
6884 return false;
6885 if (!TREE_PUBLIC (decl))
6886 return true;
6887 /* When resolution is available, just use it. */
6888 if (TREE_CODE (decl) == VAR_DECL
6889 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl)))
6891 varpool_node *vnode = varpool_node::get (decl);
6892 if (vnode
6893 && vnode->resolution != LDPR_UNKNOWN)
6894 return resolution_to_local_definition_p (vnode->resolution);
6896 else if (TREE_CODE (decl) == FUNCTION_DECL)
6898 struct cgraph_node *node = cgraph_node::get (decl);
6899 if (node
6900 && node->resolution != LDPR_UNKNOWN)
6901 return resolution_to_local_definition_p (node->resolution);
6903 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
6904 binds locally but still can be overwritten), DECL_COMMON (can be merged
6905 with a non-common definition somewhere in the same module) or
6906 DECL_EXTERNAL.
6907 This rely on fact that binds_local_p behave as decl_replaceable_p
6908 for all other declaration types. */
6909 if (DECL_WEAK (decl))
6910 return false;
6911 if (DECL_COMMON (decl)
6912 && (DECL_INITIAL (decl) == NULL
6913 || (!in_lto_p && DECL_INITIAL (decl) == error_mark_node)))
6914 return false;
6915 if (DECL_EXTERNAL (decl))
6916 return false;
6917 return true;
6920 /* A replaceable function or variable is one which may be replaced
6921 at link-time with an entirely different definition, provided that the
6922 replacement has the same type. For example, functions declared
6923 with __attribute__((weak)) on most systems are replaceable.
6925 COMDAT functions are not replaceable, since all definitions of the
6926 function must be equivalent. It is important that COMDAT functions
6927 not be treated as replaceable so that use of C++ template
6928 instantiations is not penalized. */
6930 bool
6931 decl_replaceable_p (tree decl)
6933 gcc_assert (DECL_P (decl));
6934 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
6935 return false;
6936 if (!flag_semantic_interposition
6937 && !DECL_WEAK (decl))
6938 return false;
6939 return !decl_binds_to_current_def_p (decl);
6942 /* Default function to output code that will globalize a label. A
6943 target must define GLOBAL_ASM_OP or provide its own function to
6944 globalize a label. */
6945 #ifdef GLOBAL_ASM_OP
6946 void
6947 default_globalize_label (FILE * stream, const char *name)
6949 fputs (GLOBAL_ASM_OP, stream);
6950 assemble_name (stream, name);
6951 putc ('\n', stream);
6953 #endif /* GLOBAL_ASM_OP */
6955 /* Default function to output code that will globalize a declaration. */
6956 void
6957 default_globalize_decl_name (FILE * stream, tree decl)
6959 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
6960 targetm.asm_out.globalize_label (stream, name);
6963 /* Default function to output a label for unwind information. The
6964 default is to do nothing. A target that needs nonlocal labels for
6965 unwind information must provide its own function to do this. */
6966 void
6967 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
6968 tree decl ATTRIBUTE_UNUSED,
6969 int for_eh ATTRIBUTE_UNUSED,
6970 int empty ATTRIBUTE_UNUSED)
6974 /* Default function to output a label to divide up the exception table.
6975 The default is to do nothing. A target that needs/wants to divide
6976 up the table must provide it's own function to do this. */
6977 void
6978 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
6982 /* This is how to output an internal numbered label where PREFIX is
6983 the class of label and LABELNO is the number within the class. */
6985 void
6986 default_generate_internal_label (char *buf, const char *prefix,
6987 unsigned long labelno)
6989 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6992 /* This is how to output an internal numbered label where PREFIX is
6993 the class of label and LABELNO is the number within the class. */
6995 void
6996 default_internal_label (FILE *stream, const char *prefix,
6997 unsigned long labelno)
6999 char *const buf = (char *) alloca (40 + strlen (prefix));
7000 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
7001 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
7005 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
7007 void
7008 default_asm_declare_constant_name (FILE *file, const char *name,
7009 const_tree exp ATTRIBUTE_UNUSED,
7010 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
7012 assemble_label (file, name);
7015 /* This is the default behavior at the beginning of a file. It's
7016 controlled by two other target-hook toggles. */
7017 void
7018 default_file_start (void)
7020 if (targetm.asm_file_start_app_off
7021 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
7022 fputs (ASM_APP_OFF, asm_out_file);
7024 if (targetm.asm_file_start_file_directive)
7025 output_file_directive (asm_out_file, main_input_filename);
7028 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
7029 which emits a special section directive used to indicate whether or
7030 not this object file needs an executable stack. This is primarily
7031 a GNU extension to ELF but could be used on other targets. */
7033 int trampolines_created;
7035 void
7036 file_end_indicate_exec_stack (void)
7038 unsigned int flags = SECTION_DEBUG;
7039 if (trampolines_created)
7040 flags |= SECTION_CODE;
7042 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
7045 /* Emit a special section directive to indicate that this object file
7046 was compiled with -fsplit-stack. This is used to let the linker
7047 detect calls between split-stack code and non-split-stack code, so
7048 that it can modify the split-stack code to allocate a sufficiently
7049 large stack. We emit another special section if there are any
7050 functions in this file which have the no_split_stack attribute, to
7051 prevent the linker from warning about being unable to convert the
7052 functions if they call non-split-stack code. */
7054 void
7055 file_end_indicate_split_stack (void)
7057 if (flag_split_stack)
7059 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
7060 NULL));
7061 if (saw_no_split_stack)
7062 switch_to_section (get_section (".note.GNU-no-split-stack",
7063 SECTION_DEBUG, NULL));
7067 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
7068 a get_unnamed_section callback. */
7070 void
7071 output_section_asm_op (const void *directive)
7073 fprintf (asm_out_file, "%s\n", (const char *) directive);
7076 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
7077 the current section is NEW_SECTION. */
7079 void
7080 switch_to_section (section *new_section)
7082 if (in_section == new_section)
7083 return;
7085 if (new_section->common.flags & SECTION_FORGET)
7086 in_section = NULL;
7087 else
7088 in_section = new_section;
7090 switch (SECTION_STYLE (new_section))
7092 case SECTION_NAMED:
7093 targetm.asm_out.named_section (new_section->named.name,
7094 new_section->named.common.flags,
7095 new_section->named.decl);
7096 break;
7098 case SECTION_UNNAMED:
7099 new_section->unnamed.callback (new_section->unnamed.data);
7100 break;
7102 case SECTION_NOSWITCH:
7103 gcc_unreachable ();
7104 break;
7107 new_section->common.flags |= SECTION_DECLARED;
7110 /* If block symbol SYMBOL has not yet been assigned an offset, place
7111 it at the end of its block. */
7113 void
7114 place_block_symbol (rtx symbol)
7116 unsigned HOST_WIDE_INT size, mask, offset;
7117 struct constant_descriptor_rtx *desc;
7118 unsigned int alignment;
7119 struct object_block *block;
7120 tree decl;
7122 gcc_assert (SYMBOL_REF_BLOCK (symbol));
7123 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7124 return;
7126 /* Work out the symbol's size and alignment. */
7127 if (CONSTANT_POOL_ADDRESS_P (symbol))
7129 desc = SYMBOL_REF_CONSTANT (symbol);
7130 alignment = desc->align;
7131 size = GET_MODE_SIZE (desc->mode);
7133 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7135 decl = SYMBOL_REF_DECL (symbol);
7136 alignment = DECL_ALIGN (decl);
7137 size = get_constant_size (DECL_INITIAL (decl));
7138 if ((flag_sanitize & SANITIZE_ADDRESS)
7139 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7140 && asan_protect_global (DECL_INITIAL (decl)))
7141 size += asan_red_zone_size (size);
7143 else
7145 struct symtab_node *snode;
7146 decl = SYMBOL_REF_DECL (symbol);
7148 snode = symtab_node::get (decl);
7149 if (snode->alias)
7151 rtx target = DECL_RTL (snode->ultimate_alias_target ()->decl);
7153 place_block_symbol (target);
7154 SYMBOL_REF_BLOCK_OFFSET (symbol) = SYMBOL_REF_BLOCK_OFFSET (target);
7155 return;
7157 alignment = get_variable_align (decl);
7158 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7159 if ((flag_sanitize & SANITIZE_ADDRESS)
7160 && asan_protect_global (decl))
7162 size += asan_red_zone_size (size);
7163 alignment = MAX (alignment,
7164 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7168 /* Calculate the object's offset from the start of the block. */
7169 block = SYMBOL_REF_BLOCK (symbol);
7170 mask = alignment / BITS_PER_UNIT - 1;
7171 offset = (block->size + mask) & ~mask;
7172 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7174 /* Record the block's new alignment and size. */
7175 block->alignment = MAX (block->alignment, alignment);
7176 block->size = offset + size;
7178 vec_safe_push (block->objects, symbol);
7181 /* Return the anchor that should be used to address byte offset OFFSET
7182 from the first object in BLOCK. MODEL is the TLS model used
7183 to access it. */
7186 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7187 enum tls_model model)
7189 char label[100];
7190 unsigned int begin, middle, end;
7191 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7192 rtx anchor;
7194 /* Work out the anchor's offset. Use an offset of 0 for the first
7195 anchor so that we don't pessimize the case where we take the address
7196 of a variable at the beginning of the block. This is particularly
7197 useful when a block has only one variable assigned to it.
7199 We try to place anchors RANGE bytes apart, so there can then be
7200 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7201 a ptr_mode offset. With some target settings, the lowest such
7202 anchor might be out of range for the lowest ptr_mode offset;
7203 likewise the highest anchor for the highest offset. Use anchors
7204 at the extreme ends of the ptr_mode range in such cases.
7206 All arithmetic uses unsigned integers in order to avoid
7207 signed overflow. */
7208 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7209 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7210 range = max_offset - min_offset + 1;
7211 if (range == 0)
7212 offset = 0;
7213 else
7215 bias = HOST_WIDE_INT_1U << (GET_MODE_BITSIZE (ptr_mode) - 1);
7216 if (offset < 0)
7218 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7219 delta -= delta % range;
7220 if (delta > bias)
7221 delta = bias;
7222 offset = (HOST_WIDE_INT) (-delta);
7224 else
7226 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7227 delta -= delta % range;
7228 if (delta > bias - 1)
7229 delta = bias - 1;
7230 offset = (HOST_WIDE_INT) delta;
7234 /* Do a binary search to see if there's already an anchor we can use.
7235 Set BEGIN to the new anchor's index if not. */
7236 begin = 0;
7237 end = vec_safe_length (block->anchors);
7238 while (begin != end)
7240 middle = (end + begin) / 2;
7241 anchor = (*block->anchors)[middle];
7242 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7243 end = middle;
7244 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7245 begin = middle + 1;
7246 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7247 end = middle;
7248 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7249 begin = middle + 1;
7250 else
7251 return anchor;
7254 /* Create a new anchor with a unique label. */
7255 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7256 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7257 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7258 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7260 /* Insert it at index BEGIN. */
7261 vec_safe_insert (block->anchors, begin, anchor);
7262 return anchor;
7265 /* Output the objects in BLOCK. */
7267 static void
7268 output_object_block (struct object_block *block)
7270 struct constant_descriptor_rtx *desc;
7271 unsigned int i;
7272 HOST_WIDE_INT offset;
7273 tree decl;
7274 rtx symbol;
7276 if (!block->objects)
7277 return;
7279 /* Switch to the section and make sure that the first byte is
7280 suitably aligned. */
7281 switch_to_section (block->sect);
7282 assemble_align (block->alignment);
7284 /* Define the values of all anchors relative to the current section
7285 position. */
7286 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7287 targetm.asm_out.output_anchor (symbol);
7289 /* Output the objects themselves. */
7290 offset = 0;
7291 FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7293 /* Move to the object's offset, padding with zeros if necessary. */
7294 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7295 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7296 if (CONSTANT_POOL_ADDRESS_P (symbol))
7298 desc = SYMBOL_REF_CONSTANT (symbol);
7299 output_constant_pool_1 (desc, 1);
7300 offset += GET_MODE_SIZE (desc->mode);
7302 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7304 HOST_WIDE_INT size;
7305 decl = SYMBOL_REF_DECL (symbol);
7306 assemble_constant_contents (DECL_INITIAL (decl), XSTR (symbol, 0),
7307 DECL_ALIGN (decl));
7308 size = get_constant_size (DECL_INITIAL (decl));
7309 offset += size;
7310 if ((flag_sanitize & SANITIZE_ADDRESS)
7311 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7312 && asan_protect_global (DECL_INITIAL (decl)))
7314 size = asan_red_zone_size (size);
7315 assemble_zeros (size);
7316 offset += size;
7319 else
7321 HOST_WIDE_INT size;
7322 decl = SYMBOL_REF_DECL (symbol);
7323 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7324 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7325 offset += size;
7326 if ((flag_sanitize & SANITIZE_ADDRESS)
7327 && asan_protect_global (decl))
7329 size = asan_red_zone_size (size);
7330 assemble_zeros (size);
7331 offset += size;
7337 /* A htab_traverse callback used to call output_object_block for
7338 each member of object_block_htab. */
7341 output_object_block_htab (object_block **slot, void *)
7343 output_object_block (*slot);
7344 return 1;
7347 /* Output the definitions of all object_blocks. */
7349 void
7350 output_object_blocks (void)
7352 object_block_htab->traverse<void *, output_object_block_htab> (NULL);
7355 /* This function provides a possible implementation of the
7356 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7357 by -frecord-gcc-switches it creates a new mergeable, string section in the
7358 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7359 contains the switches in ASCII format.
7361 FIXME: This code does not correctly handle double quote characters
7362 that appear inside strings, (it strips them rather than preserving them).
7363 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7364 characters - instead it treats them as sub-string separators. Since
7365 we want to emit NUL strings terminators into the object file we have to use
7366 ASM_OUTPUT_SKIP. */
7369 elf_record_gcc_switches (print_switch_type type, const char * name)
7371 switch (type)
7373 case SWITCH_TYPE_PASSED:
7374 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7375 ASM_OUTPUT_SKIP (asm_out_file, (unsigned HOST_WIDE_INT) 1);
7376 break;
7378 case SWITCH_TYPE_DESCRIPTIVE:
7379 if (name == NULL)
7381 /* Distinguish between invocations where name is NULL. */
7382 static bool started = false;
7384 if (!started)
7386 section * sec;
7388 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7389 SECTION_DEBUG
7390 | SECTION_MERGE
7391 | SECTION_STRINGS
7392 | (SECTION_ENTSIZE & 1),
7393 NULL);
7394 switch_to_section (sec);
7395 started = true;
7399 default:
7400 break;
7403 /* The return value is currently ignored by the caller, but must be 0.
7404 For -fverbose-asm the return value would be the number of characters
7405 emitted into the assembler file. */
7406 return 0;
7409 /* Emit text to declare externally defined symbols. It is needed to
7410 properly support non-default visibility. */
7411 void
7412 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7413 tree decl,
7414 const char *name ATTRIBUTE_UNUSED)
7416 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7417 set in order to avoid putting out names that are never really
7418 used. */
7419 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7420 && targetm.binds_local_p (decl))
7421 maybe_assemble_visibility (decl);
7424 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7426 void
7427 default_asm_output_source_filename (FILE *file, const char *name)
7429 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7430 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7431 #else
7432 fprintf (file, "\t.file\t");
7433 output_quoted_string (file, name);
7434 putc ('\n', file);
7435 #endif
7438 /* Output a file name in the form wanted by System V. */
7440 void
7441 output_file_directive (FILE *asm_file, const char *input_name)
7443 int len;
7444 const char *na;
7446 if (input_name == NULL)
7447 input_name = "<stdin>";
7448 else
7449 input_name = remap_debug_filename (input_name);
7451 len = strlen (input_name);
7452 na = input_name + len;
7454 /* NA gets INPUT_NAME sans directory names. */
7455 while (na > input_name)
7457 if (IS_DIR_SEPARATOR (na[-1]))
7458 break;
7459 na--;
7462 targetm.asm_out.output_source_filename (asm_file, na);
7465 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7466 EXP. */
7468 make_debug_expr_from_rtl (const_rtx exp)
7470 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7471 machine_mode mode = GET_MODE (exp);
7472 rtx dval;
7474 DECL_ARTIFICIAL (ddecl) = 1;
7475 if (REG_P (exp) && REG_EXPR (exp))
7476 type = TREE_TYPE (REG_EXPR (exp));
7477 else if (MEM_P (exp) && MEM_EXPR (exp))
7478 type = TREE_TYPE (MEM_EXPR (exp));
7479 else
7480 type = NULL_TREE;
7481 if (type && TYPE_MODE (type) == mode)
7482 TREE_TYPE (ddecl) = type;
7483 else
7484 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7485 DECL_MODE (ddecl) = mode;
7486 dval = gen_rtx_DEBUG_EXPR (mode);
7487 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7488 SET_DECL_RTL (ddecl, dval);
7489 return dval;
7492 #ifdef ELF_ASCII_ESCAPES
7493 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7495 void
7496 default_elf_asm_output_limited_string (FILE *f, const char *s)
7498 int escape;
7499 unsigned char c;
7501 fputs (STRING_ASM_OP, f);
7502 putc ('"', f);
7503 while (*s != '\0')
7505 c = *s;
7506 escape = ELF_ASCII_ESCAPES[c];
7507 switch (escape)
7509 case 0:
7510 putc (c, f);
7511 break;
7512 case 1:
7513 /* TODO: Print in hex with fast function, important for -flto. */
7514 fprintf (f, "\\%03o", c);
7515 break;
7516 default:
7517 putc ('\\', f);
7518 putc (escape, f);
7519 break;
7521 s++;
7523 putc ('\"', f);
7524 putc ('\n', f);
7527 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7529 void
7530 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7532 const char *limit = s + len;
7533 const char *last_null = NULL;
7534 unsigned bytes_in_chunk = 0;
7535 unsigned char c;
7536 int escape;
7538 for (; s < limit; s++)
7540 const char *p;
7542 if (bytes_in_chunk >= 60)
7544 putc ('\"', f);
7545 putc ('\n', f);
7546 bytes_in_chunk = 0;
7549 if (s > last_null)
7551 for (p = s; p < limit && *p != '\0'; p++)
7552 continue;
7553 last_null = p;
7555 else
7556 p = last_null;
7558 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7560 if (bytes_in_chunk > 0)
7562 putc ('\"', f);
7563 putc ('\n', f);
7564 bytes_in_chunk = 0;
7567 default_elf_asm_output_limited_string (f, s);
7568 s = p;
7570 else
7572 if (bytes_in_chunk == 0)
7573 fputs (ASCII_DATA_ASM_OP "\"", f);
7575 c = *s;
7576 escape = ELF_ASCII_ESCAPES[c];
7577 switch (escape)
7579 case 0:
7580 putc (c, f);
7581 bytes_in_chunk++;
7582 break;
7583 case 1:
7584 /* TODO: Print in hex with fast function, important for -flto. */
7585 fprintf (f, "\\%03o", c);
7586 bytes_in_chunk += 4;
7587 break;
7588 default:
7589 putc ('\\', f);
7590 putc (escape, f);
7591 bytes_in_chunk += 2;
7592 break;
7598 if (bytes_in_chunk > 0)
7600 putc ('\"', f);
7601 putc ('\n', f);
7604 #endif
7606 static GTY(()) section *elf_init_array_section;
7607 static GTY(()) section *elf_fini_array_section;
7609 static section *
7610 get_elf_initfini_array_priority_section (int priority,
7611 bool constructor_p)
7613 section *sec;
7614 if (priority != DEFAULT_INIT_PRIORITY)
7616 char buf[18];
7617 sprintf (buf, "%s.%.5u",
7618 constructor_p ? ".init_array" : ".fini_array",
7619 priority);
7620 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7622 else
7624 if (constructor_p)
7626 if (elf_init_array_section == NULL)
7627 elf_init_array_section
7628 = get_section (".init_array",
7629 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7630 sec = elf_init_array_section;
7632 else
7634 if (elf_fini_array_section == NULL)
7635 elf_fini_array_section
7636 = get_section (".fini_array",
7637 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7638 sec = elf_fini_array_section;
7641 return sec;
7644 /* Use .init_array section for constructors. */
7646 void
7647 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7649 section *sec = get_elf_initfini_array_priority_section (priority,
7650 true);
7651 assemble_addr_to_section (symbol, sec);
7654 /* Use .fini_array section for destructors. */
7656 void
7657 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7659 section *sec = get_elf_initfini_array_priority_section (priority,
7660 false);
7661 assemble_addr_to_section (symbol, sec);
7664 /* Default TARGET_ASM_OUTPUT_IDENT hook.
7666 This is a bit of a cheat. The real default is a no-op, but this
7667 hook is the default for all targets with a .ident directive. */
7669 void
7670 default_asm_output_ident_directive (const char *ident_str)
7672 const char *ident_asm_op = "\t.ident\t";
7674 /* If we are still in the front end, do not write out the string
7675 to asm_out_file. Instead, add a fake top-level asm statement.
7676 This allows the front ends to use this hook without actually
7677 writing to asm_out_file, to handle #ident or Pragma Ident. */
7678 if (symtab->state == PARSING)
7680 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
7681 symtab->finalize_toplevel_asm (build_string (strlen (buf), buf));
7683 else
7684 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
7687 #include "gt-varasm.h"