2015-03-06 Christophe Lyon <christophe.lyon@linaro.org>
[official-gcc.git] / gcc-4_9-branch / gcc / varasm.c
blob2f56ff77f35b7315d308f45022c38bcb0c7ede3f
1 /* Output variables, constants and external declarations, for GNU compiler.
2 Copyright (C) 1987-2014 Free Software Foundation, Inc.
4 This file is part of GCC.
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14 for more details.
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3. If not see
18 <http://www.gnu.org/licenses/>. */
21 /* This file handles generation of all the assembler code
22 *except* the instructions of a function.
23 This includes declarations of variables and their initial values.
25 We also output the assembler code for constants stored in memory
26 and are responsible for combining constants with the same value. */
28 #include "config.h"
29 #include "system.h"
30 #include "coretypes.h"
31 #include "tm.h"
32 #include "rtl.h"
33 #include "tree.h"
34 #include "stor-layout.h"
35 #include "stringpool.h"
36 #include "gcc-symtab.h"
37 #include "varasm.h"
38 #include "flags.h"
39 #include "function.h"
40 #include "expr.h"
41 #include "hard-reg-set.h"
42 #include "regs.h"
43 #include "output.h"
44 #include "diagnostic-core.h"
45 #include "hashtab.h"
46 #include "ggc.h"
47 #include "langhooks.h"
48 #include "tm_p.h"
49 #include "debug.h"
50 #include "target.h"
51 #include "common/common-target.h"
52 #include "targhooks.h"
53 #include "cgraph.h"
54 #include "pointer-set.h"
55 #include "asan.h"
56 #include "basic-block.h"
58 #ifdef XCOFF_DEBUGGING_INFO
59 #include "xcoffout.h" /* Needed for external data
60 declarations for e.g. AIX 4.x. */
61 #endif
63 /* The (assembler) name of the first globally-visible object output. */
64 extern GTY(()) const char *first_global_object_name;
65 extern GTY(()) const char *weak_global_object_name;
67 const char *first_global_object_name;
68 const char *weak_global_object_name;
70 struct addr_const;
71 struct constant_descriptor_rtx;
72 struct rtx_constant_pool;
74 #define n_deferred_constants (crtl->varasm.deferred_constants)
76 /* Number for making the label on the next
77 constant that is stored in memory. */
79 static GTY(()) int const_labelno;
81 /* Carry information from ASM_DECLARE_OBJECT_NAME
82 to ASM_FINISH_DECLARE_OBJECT. */
84 int size_directive_output;
86 /* The last decl for which assemble_variable was called,
87 if it did ASM_DECLARE_OBJECT_NAME.
88 If the last call to assemble_variable didn't do that,
89 this holds 0. */
91 tree last_assemble_variable_decl;
93 /* The following global variable indicates if the first basic block
94 in a function belongs to the cold partition or not. */
96 bool first_function_block_is_cold;
98 /* Whether we saw any functions with no_split_stack. */
100 static bool saw_no_split_stack;
102 static const char *strip_reg_name (const char *);
103 static int contains_pointers_p (tree);
104 #ifdef ASM_OUTPUT_EXTERNAL
105 static bool incorporeal_function_p (tree);
106 #endif
107 static void decode_addr_const (tree, struct addr_const *);
108 static hashval_t const_desc_hash (const void *);
109 static int const_desc_eq (const void *, const void *);
110 static hashval_t const_hash_1 (const tree);
111 static int compare_constant (const tree, const tree);
112 static tree copy_constant (tree);
113 static void output_constant_def_contents (rtx);
114 static void output_addressed_constants (tree);
115 static unsigned HOST_WIDE_INT output_constant (tree, unsigned HOST_WIDE_INT,
116 unsigned int);
117 static void globalize_decl (tree);
118 static bool decl_readonly_section_1 (enum section_category);
119 #ifdef BSS_SECTION_ASM_OP
120 #ifdef ASM_OUTPUT_ALIGNED_BSS
121 static void asm_output_aligned_bss (FILE *, tree, const char *,
122 unsigned HOST_WIDE_INT, int)
123 ATTRIBUTE_UNUSED;
124 #endif
125 #endif /* BSS_SECTION_ASM_OP */
126 static void mark_weak (tree);
127 static void output_constant_pool (const char *, tree);
129 /* Well-known sections, each one associated with some sort of *_ASM_OP. */
130 section *text_section;
131 section *data_section;
132 section *readonly_data_section;
133 section *sdata_section;
134 section *ctors_section;
135 section *dtors_section;
136 section *bss_section;
137 section *sbss_section;
139 /* Various forms of common section. All are guaranteed to be nonnull. */
140 section *tls_comm_section;
141 section *comm_section;
142 section *lcomm_section;
144 /* A SECTION_NOSWITCH section used for declaring global BSS variables.
145 May be null. */
146 section *bss_noswitch_section;
148 /* The section that holds the main exception table, when known. The section
149 is set either by the target's init_sections hook or by the first call to
150 switch_to_exception_section. */
151 section *exception_section;
153 /* The section that holds the DWARF2 frame unwind information, when known.
154 The section is set either by the target's init_sections hook or by the
155 first call to switch_to_eh_frame_section. */
156 section *eh_frame_section;
158 /* asm_out_file's current section. This is NULL if no section has yet
159 been selected or if we lose track of what the current section is. */
160 section *in_section;
162 /* True if code for the current function is currently being directed
163 at the cold section. */
164 bool in_cold_section_p;
166 /* A linked list of all the unnamed sections. */
167 static GTY(()) section *unnamed_sections;
169 /* Return a nonzero value if DECL has a section attribute. */
170 #define IN_NAMED_SECTION(DECL) \
171 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \
172 && DECL_SECTION_NAME (DECL) != NULL_TREE)
174 /* Hash table of named sections. */
175 static GTY((param_is (section))) htab_t section_htab;
177 /* A table of object_blocks, indexed by section. */
178 static GTY((param_is (struct object_block))) htab_t object_block_htab;
180 /* The next number to use for internal anchor labels. */
181 static GTY(()) int anchor_labelno;
183 /* A pool of constants that can be shared between functions. */
184 static GTY(()) struct rtx_constant_pool *shared_constant_pool;
186 /* Helper routines for maintaining section_htab. */
188 static int
189 section_entry_eq (const void *p1, const void *p2)
191 const section *old = (const section *) p1;
192 const char *new_name = (const char *) p2;
194 return strcmp (old->named.name, new_name) == 0;
197 static hashval_t
198 section_entry_hash (const void *p)
200 const section *old = (const section *) p;
201 return htab_hash_string (old->named.name);
204 /* Return a hash value for section SECT. */
206 static hashval_t
207 hash_section (section *sect)
209 if (sect->common.flags & SECTION_NAMED)
210 return htab_hash_string (sect->named.name);
211 return sect->common.flags;
214 /* Helper routines for maintaining object_block_htab. */
216 static int
217 object_block_entry_eq (const void *p1, const void *p2)
219 const struct object_block *old = (const struct object_block *) p1;
220 const section *new_section = (const section *) p2;
222 return old->sect == new_section;
225 static hashval_t
226 object_block_entry_hash (const void *p)
228 const struct object_block *old = (const struct object_block *) p;
229 return hash_section (old->sect);
232 /* Return a new unnamed section with the given fields. */
234 section *
235 get_unnamed_section (unsigned int flags, void (*callback) (const void *),
236 const void *data)
238 section *sect;
240 sect = ggc_alloc_section ();
241 sect->unnamed.common.flags = flags | SECTION_UNNAMED;
242 sect->unnamed.callback = callback;
243 sect->unnamed.data = data;
244 sect->unnamed.next = unnamed_sections;
246 unnamed_sections = sect;
247 return sect;
250 /* Return a SECTION_NOSWITCH section with the given fields. */
252 static section *
253 get_noswitch_section (unsigned int flags, noswitch_section_callback callback)
255 section *sect;
257 sect = ggc_alloc_section ();
258 sect->noswitch.common.flags = flags | SECTION_NOSWITCH;
259 sect->noswitch.callback = callback;
261 return sect;
264 /* Return the named section structure associated with NAME. Create
265 a new section with the given fields if no such structure exists. */
267 section *
268 get_section (const char *name, unsigned int flags, tree decl)
270 section *sect, **slot;
272 slot = (section **)
273 htab_find_slot_with_hash (section_htab, name,
274 htab_hash_string (name), INSERT);
275 flags |= SECTION_NAMED;
276 if (*slot == NULL)
278 sect = ggc_alloc_section ();
279 sect->named.common.flags = flags;
280 sect->named.name = ggc_strdup (name);
281 sect->named.decl = decl;
282 *slot = sect;
284 else
286 sect = *slot;
287 if ((sect->common.flags & ~SECTION_DECLARED) != flags
288 && ((sect->common.flags | flags) & SECTION_OVERRIDE) == 0)
290 /* It is fine if one of the section flags is
291 SECTION_WRITE | SECTION_RELRO and the other has none of these
292 flags (i.e. read-only) in named sections and either the
293 section hasn't been declared yet or has been declared as writable.
294 In that case just make sure the resulting flags are
295 SECTION_WRITE | SECTION_RELRO, ie. writable only because of
296 relocations. */
297 if (((sect->common.flags ^ flags) & (SECTION_WRITE | SECTION_RELRO))
298 == (SECTION_WRITE | SECTION_RELRO)
299 && (sect->common.flags
300 & ~(SECTION_DECLARED | SECTION_WRITE | SECTION_RELRO))
301 == (flags & ~(SECTION_WRITE | SECTION_RELRO))
302 && ((sect->common.flags & SECTION_DECLARED) == 0
303 || (sect->common.flags & SECTION_WRITE)))
305 sect->common.flags |= (SECTION_WRITE | SECTION_RELRO);
306 return sect;
308 /* Sanity check user variables for flag changes. */
309 if (sect->named.decl != NULL
310 && DECL_P (sect->named.decl)
311 && decl != sect->named.decl)
313 if (decl != NULL && DECL_P (decl))
314 error ("%+D causes a section type conflict with %D",
315 decl, sect->named.decl);
316 else
317 error ("section type conflict with %D", sect->named.decl);
318 inform (DECL_SOURCE_LOCATION (sect->named.decl),
319 "%qD was declared here", sect->named.decl);
321 else if (decl != NULL && DECL_P (decl))
322 error ("%+D causes a section type conflict", decl);
323 else
324 error ("section type conflict");
325 /* Make sure we don't error about one section multiple times. */
326 sect->common.flags |= SECTION_OVERRIDE;
329 return sect;
332 /* Return true if the current compilation mode benefits from having
333 objects grouped into blocks. */
335 static bool
336 use_object_blocks_p (void)
338 return flag_section_anchors;
341 /* Return the object_block structure for section SECT. Create a new
342 structure if we haven't created one already. Return null if SECT
343 itself is null. */
345 static struct object_block *
346 get_block_for_section (section *sect)
348 struct object_block *block;
349 void **slot;
351 if (sect == NULL)
352 return NULL;
354 slot = htab_find_slot_with_hash (object_block_htab, sect,
355 hash_section (sect), INSERT);
356 block = (struct object_block *) *slot;
357 if (block == NULL)
359 block = ggc_alloc_cleared_object_block ();
360 block->sect = sect;
361 *slot = block;
363 return block;
366 /* Create a symbol with label LABEL and place it at byte offset
367 OFFSET in BLOCK. OFFSET can be negative if the symbol's offset
368 is not yet known. LABEL must be a garbage-collected string. */
370 static rtx
371 create_block_symbol (const char *label, struct object_block *block,
372 HOST_WIDE_INT offset)
374 rtx symbol;
375 unsigned int size;
377 /* Create the extended SYMBOL_REF. */
378 size = RTX_HDR_SIZE + sizeof (struct block_symbol);
379 symbol = ggc_alloc_rtx_def (size);
381 /* Initialize the normal SYMBOL_REF fields. */
382 memset (symbol, 0, size);
383 PUT_CODE (symbol, SYMBOL_REF);
384 PUT_MODE (symbol, Pmode);
385 XSTR (symbol, 0) = label;
386 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_HAS_BLOCK_INFO;
388 /* Initialize the block_symbol stuff. */
389 SYMBOL_REF_BLOCK (symbol) = block;
390 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
392 return symbol;
395 /* Return a section with a particular name and with whatever SECTION_*
396 flags section_type_flags deems appropriate. The name of the section
397 is taken from NAME if nonnull, otherwise it is taken from DECL's
398 DECL_SECTION_NAME. DECL is the decl associated with the section
399 (see the section comment for details) and RELOC is as for
400 section_type_flags. */
402 section *
403 get_named_section (tree decl, const char *name, int reloc)
405 unsigned int flags;
407 if (name == NULL)
409 gcc_assert (decl && DECL_P (decl) && DECL_SECTION_NAME (decl));
410 name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
413 flags = targetm.section_type_flags (decl, name, reloc);
414 return get_section (name, flags, decl);
417 /* If required, set DECL_SECTION_NAME to a unique name. */
419 void
420 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
421 int flag_function_or_data_sections)
423 if (DECL_SECTION_NAME (decl) == NULL_TREE
424 && targetm_common.have_named_sections
425 && (flag_function_or_data_sections
426 || DECL_ONE_ONLY (decl)))
428 targetm.asm_out.unique_section (decl, reloc);
429 DECL_HAS_IMPLICIT_SECTION_NAME_P (decl) = true;
433 #ifdef BSS_SECTION_ASM_OP
435 #ifdef ASM_OUTPUT_ALIGNED_BSS
437 /* Utility function for targets to use in implementing
438 ASM_OUTPUT_ALIGNED_BSS.
439 ??? It is believed that this function will work in most cases so such
440 support is localized here. */
442 static void
443 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
444 const char *name, unsigned HOST_WIDE_INT size,
445 int align)
447 switch_to_section (bss_section);
448 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
449 #ifdef ASM_DECLARE_OBJECT_NAME
450 last_assemble_variable_decl = decl;
451 ASM_DECLARE_OBJECT_NAME (file, name, decl);
452 #else
453 /* Standard thing is just output label for the object. */
454 ASM_OUTPUT_LABEL (file, name);
455 #endif /* ASM_DECLARE_OBJECT_NAME */
456 ASM_OUTPUT_SKIP (file, size ? size : 1);
459 #endif
461 #endif /* BSS_SECTION_ASM_OP */
463 #ifndef USE_SELECT_SECTION_FOR_FUNCTIONS
464 /* Return the hot section for function DECL. Return text_section for
465 null DECLs. */
467 static section *
468 hot_function_section (tree decl)
470 if (decl != NULL_TREE
471 && DECL_SECTION_NAME (decl) != NULL_TREE
472 && targetm_common.have_named_sections)
473 return get_named_section (decl, NULL, 0);
474 else
475 return text_section;
477 #endif
479 /* Return section for TEXT_SECTION_NAME if DECL or DECL_SECTION_NAME (DECL)
480 is NULL.
482 When DECL_SECTION_NAME is non-NULL and it is implicit section and
483 NAMED_SECTION_SUFFIX is non-NULL, then produce section called
484 concatenate the name with NAMED_SECTION_SUFFIX.
485 Otherwise produce "TEXT_SECTION_NAME.IMPLICIT_NAME". */
487 section *
488 get_named_text_section (tree decl,
489 const char *text_section_name,
490 const char *named_section_suffix)
492 if (decl && DECL_SECTION_NAME (decl))
494 if (named_section_suffix)
496 tree dsn = DECL_SECTION_NAME (decl);
497 const char *stripped_name;
498 char *name, *buffer;
500 name = (char *) alloca (TREE_STRING_LENGTH (dsn) + 1);
501 memcpy (name, TREE_STRING_POINTER (dsn),
502 TREE_STRING_LENGTH (dsn) + 1);
504 stripped_name = targetm.strip_name_encoding (name);
506 buffer = ACONCAT ((stripped_name, named_section_suffix, NULL));
507 return get_named_section (decl, buffer, 0);
509 else if (DECL_HAS_IMPLICIT_SECTION_NAME_P (decl))
511 const char *name;
513 /* Do not try to split gnu_linkonce functions. This gets somewhat
514 slipperly. */
515 if (DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP)
516 return NULL;
517 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
518 name = targetm.strip_name_encoding (name);
519 return get_named_section (decl, ACONCAT ((text_section_name, ".",
520 name, NULL)), 0);
522 else
523 return NULL;
525 return get_named_section (decl, text_section_name, 0);
528 /* Choose named function section based on its frequency. */
530 section *
531 default_function_section (tree decl, enum node_frequency freq,
532 bool startup, bool exit)
534 #if defined HAVE_LD_EH_GC_SECTIONS && defined HAVE_LD_EH_GC_SECTIONS_BUG
535 /* Old GNU linkers have buggy --gc-section support, which sometimes
536 results in .gcc_except_table* sections being garbage collected. */
537 if (decl
538 && DECL_SECTION_NAME (decl)
539 && DECL_HAS_IMPLICIT_SECTION_NAME_P (decl))
540 return NULL;
541 #endif
543 if (!flag_reorder_functions
544 || !targetm_common.have_named_sections)
545 return NULL;
546 /* Startup code should go to startup subsection unless it is
547 unlikely executed (this happens especially with function splitting
548 where we can split away unnecessary parts of static constructors. */
549 if (startup && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
551 /* If we do have a profile or(and) LTO phase is executed, we do not need
552 these ELF section. */
553 if (!in_lto_p || !flag_profile_values)
554 return get_named_text_section (decl, ".text.startup", NULL);
555 else
556 return NULL;
559 /* Similarly for exit. */
560 if (exit && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
561 return get_named_text_section (decl, ".text.exit", NULL);
563 /* Group cold functions together, similarly for hot code. */
564 switch (freq)
566 case NODE_FREQUENCY_UNLIKELY_EXECUTED:
567 return get_named_text_section (decl, ".text.unlikely", NULL);
568 case NODE_FREQUENCY_HOT:
569 /* If we do have a profile or(and) LTO phase is executed, we do not need
570 these ELF section. */
571 if (!in_lto_p || !flag_profile_values)
572 return get_named_text_section (decl, ".text.hot", NULL);
573 default:
574 return NULL;
578 /* Return the section for function DECL.
580 If DECL is NULL_TREE, return the text section. We can be passed
581 NULL_TREE under some circumstances by dbxout.c at least.
583 If FORCE_COLD is true, return cold function section ignoring
584 the frequency info of cgraph_node. */
586 static section *
587 function_section_1 (tree decl, bool force_cold)
589 section *section = NULL;
590 enum node_frequency freq = NODE_FREQUENCY_NORMAL;
591 bool startup = false, exit = false;
593 if (decl)
595 struct cgraph_node *node = cgraph_get_node (decl);
597 if (node)
599 freq = node->frequency;
600 startup = node->only_called_at_startup;
601 exit = node->only_called_at_exit;
604 if (force_cold)
605 freq = NODE_FREQUENCY_UNLIKELY_EXECUTED;
607 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
608 if (decl != NULL_TREE
609 && DECL_SECTION_NAME (decl) != NULL_TREE)
611 if (targetm.asm_out.function_section)
612 section = targetm.asm_out.function_section (decl, freq,
613 startup, exit);
614 if (section)
615 return section;
616 return get_named_section (decl, NULL, 0);
618 else
619 return targetm.asm_out.select_section
620 (decl, freq == NODE_FREQUENCY_UNLIKELY_EXECUTED,
621 DECL_ALIGN (decl));
622 #else
623 if (targetm.asm_out.function_section)
624 section = targetm.asm_out.function_section (decl, freq, startup, exit);
625 if (section)
626 return section;
627 return hot_function_section (decl);
628 #endif
631 /* Return the section for function DECL.
633 If DECL is NULL_TREE, return the text section. We can be passed
634 NULL_TREE under some circumstances by dbxout.c at least. */
636 section *
637 function_section (tree decl)
639 /* Handle cases where function splitting code decides
640 to put function entry point into unlikely executed section
641 despite the fact that the function itself is not cold
642 (i.e. it is called rarely but contains a hot loop that is
643 better to live in hot subsection for the code locality). */
644 return function_section_1 (decl,
645 first_function_block_is_cold);
648 /* Return the section for the current function, take IN_COLD_SECTION_P
649 into account. */
651 section *
652 current_function_section (void)
654 return function_section_1 (current_function_decl, in_cold_section_p);
657 /* Tell assembler to switch to unlikely-to-be-executed text section. */
659 section *
660 unlikely_text_section (void)
662 return function_section_1 (current_function_decl, true);
665 /* When called within a function context, return true if the function
666 has been assigned a cold text section and if SECT is that section.
667 When called outside a function context, return true if SECT is the
668 default cold section. */
670 bool
671 unlikely_text_section_p (section *sect)
673 return sect == function_section_1 (current_function_decl, true);
676 /* Return the read-only data section associated with function DECL. */
678 section *
679 default_function_rodata_section (tree decl)
681 if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
683 const char *name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
685 if (DECL_ONE_ONLY (decl) && HAVE_COMDAT_GROUP)
687 const char *dot;
688 size_t len;
689 char* rname;
691 dot = strchr (name + 1, '.');
692 if (!dot)
693 dot = name;
694 len = strlen (dot) + 8;
695 rname = (char *) alloca (len);
697 strcpy (rname, ".rodata");
698 strcat (rname, dot);
699 return get_section (rname, SECTION_LINKONCE, decl);
701 /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo. */
702 else if (DECL_ONE_ONLY (decl)
703 && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
705 size_t len = strlen (name) + 1;
706 char *rname = (char *) alloca (len);
708 memcpy (rname, name, len);
709 rname[14] = 'r';
710 return get_section (rname, SECTION_LINKONCE, decl);
712 /* For .text.foo we want to use .rodata.foo. */
713 else if (flag_function_sections && flag_data_sections
714 && strncmp (name, ".text.", 6) == 0)
716 size_t len = strlen (name) + 1;
717 char *rname = (char *) alloca (len + 2);
719 memcpy (rname, ".rodata", 7);
720 memcpy (rname + 7, name + 5, len - 5);
721 return get_section (rname, 0, decl);
725 return readonly_data_section;
728 /* Return the read-only data section associated with function DECL
729 for targets where that section should be always the single
730 readonly data section. */
732 section *
733 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
735 return readonly_data_section;
738 /* Return the section to use for string merging. */
740 static section *
741 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
742 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
743 unsigned int flags ATTRIBUTE_UNUSED)
745 HOST_WIDE_INT len;
747 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
748 && TREE_CODE (decl) == STRING_CST
749 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
750 && align <= 256
751 && (len = int_size_in_bytes (TREE_TYPE (decl))) > 0
752 && TREE_STRING_LENGTH (decl) >= len)
754 enum machine_mode mode;
755 unsigned int modesize;
756 const char *str;
757 HOST_WIDE_INT i;
758 int j, unit;
759 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
760 char *name = (char *) alloca (strlen (prefix) + 30);
762 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
763 modesize = GET_MODE_BITSIZE (mode);
764 if (modesize >= 8 && modesize <= 256
765 && (modesize & (modesize - 1)) == 0)
767 if (align < modesize)
768 align = modesize;
770 str = TREE_STRING_POINTER (decl);
771 unit = GET_MODE_SIZE (mode);
773 /* Check for embedded NUL characters. */
774 for (i = 0; i < len; i += unit)
776 for (j = 0; j < unit; j++)
777 if (str[i + j] != '\0')
778 break;
779 if (j == unit)
780 break;
782 if (i == len - unit)
784 sprintf (name, "%s.str%d.%d", prefix,
785 modesize / 8, (int) (align / 8));
786 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
787 return get_section (name, flags, NULL);
792 return readonly_data_section;
795 /* Return the section to use for constant merging. */
797 section *
798 mergeable_constant_section (enum machine_mode mode ATTRIBUTE_UNUSED,
799 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
800 unsigned int flags ATTRIBUTE_UNUSED)
802 unsigned int modesize = GET_MODE_BITSIZE (mode);
804 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
805 && mode != VOIDmode
806 && mode != BLKmode
807 && modesize <= align
808 && align >= 8
809 && align <= 256
810 && (align & (align - 1)) == 0)
812 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
813 char *name = (char *) alloca (strlen (prefix) + 30);
815 sprintf (name, "%s.cst%d", prefix, (int) (align / 8));
816 flags |= (align / 8) | SECTION_MERGE;
817 return get_section (name, flags, NULL);
819 return readonly_data_section;
822 /* Given NAME, a putative register name, discard any customary prefixes. */
824 static const char *
825 strip_reg_name (const char *name)
827 #ifdef REGISTER_PREFIX
828 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
829 name += strlen (REGISTER_PREFIX);
830 #endif
831 if (name[0] == '%' || name[0] == '#')
832 name++;
833 return name;
836 /* The user has asked for a DECL to have a particular name. Set (or
837 change) it in such a way that we don't prefix an underscore to
838 it. */
839 void
840 set_user_assembler_name (tree decl, const char *name)
842 char *starred = (char *) alloca (strlen (name) + 2);
843 starred[0] = '*';
844 strcpy (starred + 1, name);
845 change_decl_assembler_name (decl, get_identifier (starred));
846 SET_DECL_RTL (decl, NULL_RTX);
849 /* Decode an `asm' spec for a declaration as a register name.
850 Return the register number, or -1 if nothing specified,
851 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
852 or -3 if ASMSPEC is `cc' and is not recognized,
853 or -4 if ASMSPEC is `memory' and is not recognized.
854 Accept an exact spelling or a decimal number.
855 Prefixes such as % are optional. */
858 decode_reg_name_and_count (const char *asmspec, int *pnregs)
860 /* Presume just one register is clobbered. */
861 *pnregs = 1;
863 if (asmspec != 0)
865 int i;
867 /* Get rid of confusing prefixes. */
868 asmspec = strip_reg_name (asmspec);
870 /* Allow a decimal number as a "register name". */
871 for (i = strlen (asmspec) - 1; i >= 0; i--)
872 if (! ISDIGIT (asmspec[i]))
873 break;
874 if (asmspec[0] != 0 && i < 0)
876 i = atoi (asmspec);
877 if (i < FIRST_PSEUDO_REGISTER && i >= 0)
878 return i;
879 else
880 return -2;
883 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
884 if (reg_names[i][0]
885 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
886 return i;
888 #ifdef OVERLAPPING_REGISTER_NAMES
890 static const struct
892 const char *const name;
893 const int number;
894 const int nregs;
895 } table[] = OVERLAPPING_REGISTER_NAMES;
897 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
898 if (table[i].name[0]
899 && ! strcmp (asmspec, table[i].name))
901 *pnregs = table[i].nregs;
902 return table[i].number;
905 #endif /* OVERLAPPING_REGISTER_NAMES */
907 #ifdef ADDITIONAL_REGISTER_NAMES
909 static const struct { const char *const name; const int number; } table[]
910 = ADDITIONAL_REGISTER_NAMES;
912 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
913 if (table[i].name[0]
914 && ! strcmp (asmspec, table[i].name))
915 return table[i].number;
917 #endif /* ADDITIONAL_REGISTER_NAMES */
919 if (!strcmp (asmspec, "memory"))
920 return -4;
922 if (!strcmp (asmspec, "cc"))
923 return -3;
925 return -2;
928 return -1;
932 decode_reg_name (const char *name)
934 int count;
935 return decode_reg_name_and_count (name, &count);
939 /* Return true if DECL's initializer is suitable for a BSS section. */
941 bool
942 bss_initializer_p (const_tree decl)
944 return (DECL_INITIAL (decl) == NULL
945 || DECL_INITIAL (decl) == error_mark_node
946 || (flag_zero_initialized_in_bss
947 /* Leave constant zeroes in .rodata so they
948 can be shared. */
949 && !TREE_READONLY (decl)
950 && initializer_zerop (DECL_INITIAL (decl))));
953 /* Compute the alignment of variable specified by DECL.
954 DONT_OUTPUT_DATA is from assemble_variable. */
956 void
957 align_variable (tree decl, bool dont_output_data)
959 unsigned int align = DECL_ALIGN (decl);
961 /* In the case for initialing an array whose length isn't specified,
962 where we have not yet been able to do the layout,
963 figure out the proper alignment now. */
964 if (dont_output_data && DECL_SIZE (decl) == 0
965 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
966 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
968 /* Some object file formats have a maximum alignment which they support.
969 In particular, a.out format supports a maximum alignment of 4. */
970 if (align > MAX_OFILE_ALIGNMENT)
972 error ("alignment of %q+D is greater than maximum object "
973 "file alignment %d", decl,
974 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
975 align = MAX_OFILE_ALIGNMENT;
978 if (! DECL_USER_ALIGN (decl))
980 #ifdef DATA_ABI_ALIGNMENT
981 unsigned int data_abi_align
982 = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
983 /* For backwards compatibility, don't assume the ABI alignment for
984 TLS variables. */
985 if (! DECL_THREAD_LOCAL_P (decl) || data_abi_align <= BITS_PER_WORD)
986 align = data_abi_align;
987 #endif
989 /* On some machines, it is good to increase alignment sometimes.
990 But as DECL_ALIGN is used both for actually emitting the variable
991 and for code accessing the variable as guaranteed alignment, we
992 can only increase the alignment if it is a performance optimization
993 if the references to it must bind to the current definition. */
994 if (decl_binds_to_current_def_p (decl))
996 #ifdef DATA_ALIGNMENT
997 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
998 /* Don't increase alignment too much for TLS variables - TLS space
999 is too precious. */
1000 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1001 align = data_align;
1002 #endif
1003 #ifdef CONSTANT_ALIGNMENT
1004 if (DECL_INITIAL (decl) != 0
1005 && DECL_INITIAL (decl) != error_mark_node)
1007 unsigned int const_align
1008 = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
1009 /* Don't increase alignment too much for TLS variables - TLS
1010 space is too precious. */
1011 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1012 align = const_align;
1014 #endif
1018 /* Reset the alignment in case we have made it tighter, so we can benefit
1019 from it in get_pointer_alignment. */
1020 DECL_ALIGN (decl) = align;
1023 /* Return DECL_ALIGN (decl), possibly increased for optimization purposes
1024 beyond what align_variable returned. */
1026 static unsigned int
1027 get_variable_align (tree decl)
1029 unsigned int align = DECL_ALIGN (decl);
1031 /* For user aligned vars or static vars align_variable already did
1032 everything. */
1033 if (DECL_USER_ALIGN (decl) || !TREE_PUBLIC (decl))
1034 return align;
1036 #ifdef DATA_ABI_ALIGNMENT
1037 if (DECL_THREAD_LOCAL_P (decl))
1038 align = DATA_ABI_ALIGNMENT (TREE_TYPE (decl), align);
1039 #endif
1041 /* For decls that bind to the current definition, align_variable
1042 did also everything, except for not assuming ABI required alignment
1043 of TLS variables. For other vars, increase the alignment here
1044 as an optimization. */
1045 if (!decl_binds_to_current_def_p (decl))
1047 /* On some machines, it is good to increase alignment sometimes. */
1048 #ifdef DATA_ALIGNMENT
1049 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1050 /* Don't increase alignment too much for TLS variables - TLS space
1051 is too precious. */
1052 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1053 align = data_align;
1054 #endif
1055 #ifdef CONSTANT_ALIGNMENT
1056 if (DECL_INITIAL (decl) != 0 && DECL_INITIAL (decl) != error_mark_node)
1058 unsigned int const_align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl),
1059 align);
1060 /* Don't increase alignment too much for TLS variables - TLS space
1061 is too precious. */
1062 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1063 align = const_align;
1065 #endif
1068 return align;
1071 /* Return the section into which the given VAR_DECL or CONST_DECL
1072 should be placed. PREFER_NOSWITCH_P is true if a noswitch
1073 section should be used wherever possible. */
1075 section *
1076 get_variable_section (tree decl, bool prefer_noswitch_p)
1078 addr_space_t as = ADDR_SPACE_GENERIC;
1079 int reloc;
1081 if (TREE_TYPE (decl) != error_mark_node)
1082 as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1084 if (DECL_COMMON (decl))
1086 /* If the decl has been given an explicit section name, or it resides
1087 in a non-generic address space, then it isn't common, and shouldn't
1088 be handled as such. */
1089 gcc_assert (DECL_SECTION_NAME (decl) == NULL
1090 && ADDR_SPACE_GENERIC_P (as));
1091 if (DECL_THREAD_LOCAL_P (decl))
1092 return tls_comm_section;
1093 else if (TREE_PUBLIC (decl) && bss_initializer_p (decl))
1094 return comm_section;
1097 if (DECL_INITIAL (decl) == error_mark_node)
1098 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1099 else if (DECL_INITIAL (decl))
1100 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1101 else
1102 reloc = 0;
1104 resolve_unique_section (decl, reloc, flag_data_sections);
1105 if (IN_NAMED_SECTION (decl))
1106 return get_named_section (decl, NULL, reloc);
1108 if (ADDR_SPACE_GENERIC_P (as)
1109 && !DECL_THREAD_LOCAL_P (decl)
1110 && !(prefer_noswitch_p && targetm.have_switchable_bss_sections)
1111 && bss_initializer_p (decl))
1113 if (!TREE_PUBLIC (decl)
1114 && !((flag_sanitize & SANITIZE_ADDRESS)
1115 && asan_protect_global (decl)))
1116 return lcomm_section;
1117 if (bss_noswitch_section)
1118 return bss_noswitch_section;
1121 return targetm.asm_out.select_section (decl, reloc,
1122 get_variable_align (decl));
1125 /* Return the block into which object_block DECL should be placed. */
1127 static struct object_block *
1128 get_block_for_decl (tree decl)
1130 section *sect;
1132 if (TREE_CODE (decl) == VAR_DECL)
1134 /* The object must be defined in this translation unit. */
1135 if (DECL_EXTERNAL (decl))
1136 return NULL;
1138 /* There's no point using object blocks for something that is
1139 isolated by definition. */
1140 if (DECL_ONE_ONLY (decl))
1141 return NULL;
1144 /* We can only calculate block offsets if the decl has a known
1145 constant size. */
1146 if (DECL_SIZE_UNIT (decl) == NULL)
1147 return NULL;
1148 if (!tree_fits_uhwi_p (DECL_SIZE_UNIT (decl)))
1149 return NULL;
1151 /* Find out which section should contain DECL. We cannot put it into
1152 an object block if it requires a standalone definition. */
1153 if (TREE_CODE (decl) == VAR_DECL)
1154 align_variable (decl, 0);
1155 sect = get_variable_section (decl, true);
1156 if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
1157 return NULL;
1159 return get_block_for_section (sect);
1162 /* Make sure block symbol SYMBOL is in block BLOCK. */
1164 static void
1165 change_symbol_block (rtx symbol, struct object_block *block)
1167 if (block != SYMBOL_REF_BLOCK (symbol))
1169 gcc_assert (SYMBOL_REF_BLOCK_OFFSET (symbol) < 0);
1170 SYMBOL_REF_BLOCK (symbol) = block;
1174 /* Return true if it is possible to put DECL in an object_block. */
1176 static bool
1177 use_blocks_for_decl_p (tree decl)
1179 /* Only data DECLs can be placed into object blocks. */
1180 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != CONST_DECL)
1181 return false;
1183 /* Detect decls created by dw2_force_const_mem. Such decls are
1184 special because DECL_INITIAL doesn't specify the decl's true value.
1185 dw2_output_indirect_constants will instead call assemble_variable
1186 with dont_output_data set to 1 and then print the contents itself. */
1187 if (DECL_INITIAL (decl) == decl)
1188 return false;
1190 /* If this decl is an alias, then we don't want to emit a
1191 definition. */
1192 if (lookup_attribute ("alias", DECL_ATTRIBUTES (decl)))
1193 return false;
1195 return targetm.use_blocks_for_decl_p (decl);
1198 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
1199 have static storage duration. In other words, it should not be an
1200 automatic variable, including PARM_DECLs.
1202 There is, however, one exception: this function handles variables
1203 explicitly placed in a particular register by the user.
1205 This is never called for PARM_DECL nodes. */
1207 void
1208 make_decl_rtl (tree decl)
1210 const char *name = 0;
1211 int reg_number;
1212 rtx x;
1214 /* Check that we are not being given an automatic variable. */
1215 gcc_assert (TREE_CODE (decl) != PARM_DECL
1216 && TREE_CODE (decl) != RESULT_DECL);
1218 /* A weak alias has TREE_PUBLIC set but not the other bits. */
1219 gcc_assert (TREE_CODE (decl) != VAR_DECL
1220 || TREE_STATIC (decl)
1221 || TREE_PUBLIC (decl)
1222 || DECL_EXTERNAL (decl)
1223 || DECL_REGISTER (decl));
1225 /* And that we were not given a type or a label. */
1226 gcc_assert (TREE_CODE (decl) != TYPE_DECL
1227 && TREE_CODE (decl) != LABEL_DECL);
1229 /* For a duplicate declaration, we can be called twice on the
1230 same DECL node. Don't discard the RTL already made. */
1231 if (DECL_RTL_SET_P (decl))
1233 /* If the old RTL had the wrong mode, fix the mode. */
1234 x = DECL_RTL (decl);
1235 if (GET_MODE (x) != DECL_MODE (decl))
1236 SET_DECL_RTL (decl, adjust_address_nv (x, DECL_MODE (decl), 0));
1238 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1239 return;
1241 /* ??? Another way to do this would be to maintain a hashed
1242 table of such critters. Instead of adding stuff to a DECL
1243 to give certain attributes to it, we could use an external
1244 hash map from DECL to set of attributes. */
1246 /* Let the target reassign the RTL if it wants.
1247 This is necessary, for example, when one machine specific
1248 decl attribute overrides another. */
1249 targetm.encode_section_info (decl, DECL_RTL (decl), false);
1251 /* If the symbol has a SYMBOL_REF_BLOCK field, update it based
1252 on the new decl information. */
1253 if (MEM_P (x)
1254 && GET_CODE (XEXP (x, 0)) == SYMBOL_REF
1255 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (x, 0)))
1256 change_symbol_block (XEXP (x, 0), get_block_for_decl (decl));
1258 return;
1261 /* If this variable belongs to the global constant pool, retrieve the
1262 pre-computed RTL or recompute it in LTO mode. */
1263 if (TREE_CODE (decl) == VAR_DECL && DECL_IN_CONSTANT_POOL (decl))
1265 SET_DECL_RTL (decl, output_constant_def (DECL_INITIAL (decl), 1));
1266 return;
1269 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
1271 if (name[0] != '*' && TREE_CODE (decl) != FUNCTION_DECL
1272 && DECL_REGISTER (decl))
1274 error ("register name not specified for %q+D", decl);
1276 else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1278 const char *asmspec = name+1;
1279 enum machine_mode mode = DECL_MODE (decl);
1280 reg_number = decode_reg_name (asmspec);
1281 /* First detect errors in declaring global registers. */
1282 if (reg_number == -1)
1283 error ("register name not specified for %q+D", decl);
1284 else if (reg_number < 0)
1285 error ("invalid register name for %q+D", decl);
1286 else if (mode == BLKmode)
1287 error ("data type of %q+D isn%'t suitable for a register",
1288 decl);
1289 else if (!in_hard_reg_set_p (accessible_reg_set, mode, reg_number))
1290 error ("the register specified for %q+D cannot be accessed"
1291 " by the current target", decl);
1292 else if (!in_hard_reg_set_p (operand_reg_set, mode, reg_number))
1293 error ("the register specified for %q+D is not general enough"
1294 " to be used as a register variable", decl);
1295 else if (!HARD_REGNO_MODE_OK (reg_number, mode))
1296 error ("register specified for %q+D isn%'t suitable for data type",
1297 decl);
1298 /* Now handle properly declared static register variables. */
1299 else
1301 int nregs;
1303 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
1305 DECL_INITIAL (decl) = 0;
1306 error ("global register variable has initial value");
1308 if (TREE_THIS_VOLATILE (decl))
1309 warning (OPT_Wvolatile_register_var,
1310 "optimization may eliminate reads and/or "
1311 "writes to register variables");
1313 /* If the user specified one of the eliminables registers here,
1314 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
1315 confused with that register and be eliminated. This usage is
1316 somewhat suspect... */
1318 SET_DECL_RTL (decl, gen_rtx_raw_REG (mode, reg_number));
1319 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
1320 REG_USERVAR_P (DECL_RTL (decl)) = 1;
1322 if (TREE_STATIC (decl))
1324 /* Make this register global, so not usable for anything
1325 else. */
1326 #ifdef ASM_DECLARE_REGISTER_GLOBAL
1327 name = IDENTIFIER_POINTER (DECL_NAME (decl));
1328 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
1329 #endif
1330 nregs = hard_regno_nregs[reg_number][mode];
1331 while (nregs > 0)
1332 globalize_reg (decl, reg_number + --nregs);
1335 /* As a register variable, it has no section. */
1336 return;
1338 /* Avoid internal errors from invalid register
1339 specifications. */
1340 SET_DECL_ASSEMBLER_NAME (decl, NULL_TREE);
1341 DECL_HARD_REGISTER (decl) = 0;
1342 return;
1344 /* Now handle ordinary static variables and functions (in memory).
1345 Also handle vars declared register invalidly. */
1346 else if (name[0] == '*')
1348 #ifdef REGISTER_PREFIX
1349 if (strlen (REGISTER_PREFIX) != 0)
1351 reg_number = decode_reg_name (name);
1352 if (reg_number >= 0 || reg_number == -3)
1353 error ("register name given for non-register variable %q+D", decl);
1355 #endif
1358 /* Specifying a section attribute on a variable forces it into a
1359 non-.bss section, and thus it cannot be common. */
1360 /* FIXME: In general this code should not be necessary because
1361 visibility pass is doing the same work. But notice_global_symbol
1362 is called early and it needs to make DECL_RTL to get the name.
1363 we take care of recomputing the DECL_RTL after visibility is changed. */
1364 if (TREE_CODE (decl) == VAR_DECL
1365 && DECL_SECTION_NAME (decl) != NULL_TREE
1366 && DECL_INITIAL (decl) == NULL_TREE
1367 && DECL_COMMON (decl))
1368 DECL_COMMON (decl) = 0;
1370 /* Variables can't be both common and weak. */
1371 if (TREE_CODE (decl) == VAR_DECL && DECL_WEAK (decl))
1372 DECL_COMMON (decl) = 0;
1374 if (use_object_blocks_p () && use_blocks_for_decl_p (decl))
1375 x = create_block_symbol (name, get_block_for_decl (decl), -1);
1376 else
1378 enum machine_mode address_mode = Pmode;
1379 if (TREE_TYPE (decl) != error_mark_node)
1381 addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1382 address_mode = targetm.addr_space.address_mode (as);
1384 x = gen_rtx_SYMBOL_REF (address_mode, name);
1386 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
1387 SET_SYMBOL_REF_DECL (x, decl);
1389 x = gen_rtx_MEM (DECL_MODE (decl), x);
1390 if (TREE_CODE (decl) != FUNCTION_DECL)
1391 set_mem_attributes (x, decl, 1);
1392 SET_DECL_RTL (decl, x);
1394 /* Optionally set flags or add text to the name to record information
1395 such as that it is a function name.
1396 If the name is changed, the macro ASM_OUTPUT_LABELREF
1397 will have to know how to strip this information. */
1398 targetm.encode_section_info (decl, DECL_RTL (decl), true);
1401 /* Like make_decl_rtl, but inhibit creation of new alias sets when
1402 calling make_decl_rtl. Also, reset DECL_RTL before returning the
1403 rtl. */
1406 make_decl_rtl_for_debug (tree decl)
1408 unsigned int save_aliasing_flag;
1409 rtx rtl;
1411 if (DECL_RTL_SET_P (decl))
1412 return DECL_RTL (decl);
1414 /* Kludge alert! Somewhere down the call chain, make_decl_rtl will
1415 call new_alias_set. If running with -fcompare-debug, sometimes
1416 we do not want to create alias sets that will throw the alias
1417 numbers off in the comparison dumps. So... clearing
1418 flag_strict_aliasing will keep new_alias_set() from creating a
1419 new set. */
1420 save_aliasing_flag = flag_strict_aliasing;
1421 flag_strict_aliasing = 0;
1423 rtl = DECL_RTL (decl);
1424 /* Reset DECL_RTL back, as various parts of the compiler expects
1425 DECL_RTL set meaning it is actually going to be output. */
1426 SET_DECL_RTL (decl, NULL);
1428 flag_strict_aliasing = save_aliasing_flag;
1429 return rtl;
1432 /* Output a string of literal assembler code
1433 for an `asm' keyword used between functions. */
1435 void
1436 assemble_asm (tree string)
1438 const char *p;
1439 app_enable ();
1441 if (TREE_CODE (string) == ADDR_EXPR)
1442 string = TREE_OPERAND (string, 0);
1444 p = TREE_STRING_POINTER (string);
1445 fprintf (asm_out_file, "%s%s\n", p[0] == '\t' ? "" : "\t", p);
1448 /* Write the address of the entity given by SYMBOL to SEC. */
1449 void
1450 assemble_addr_to_section (rtx symbol, section *sec)
1452 switch_to_section (sec);
1453 assemble_align (POINTER_SIZE);
1454 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1457 /* Return the numbered .ctors.N (if CONSTRUCTOR_P) or .dtors.N (if
1458 not) section for PRIORITY. */
1459 section *
1460 get_cdtor_priority_section (int priority, bool constructor_p)
1462 char buf[16];
1464 /* ??? This only works reliably with the GNU linker. */
1465 sprintf (buf, "%s.%.5u",
1466 constructor_p ? ".ctors" : ".dtors",
1467 /* Invert the numbering so the linker puts us in the proper
1468 order; constructors are run from right to left, and the
1469 linker sorts in increasing order. */
1470 MAX_INIT_PRIORITY - priority);
1471 return get_section (buf, SECTION_WRITE, NULL);
1474 void
1475 default_named_section_asm_out_destructor (rtx symbol, int priority)
1477 section *sec;
1479 if (priority != DEFAULT_INIT_PRIORITY)
1480 sec = get_cdtor_priority_section (priority,
1481 /*constructor_p=*/false);
1482 else
1483 sec = get_section (".dtors", SECTION_WRITE, NULL);
1485 assemble_addr_to_section (symbol, sec);
1488 #ifdef DTORS_SECTION_ASM_OP
1489 void
1490 default_dtor_section_asm_out_destructor (rtx symbol,
1491 int priority ATTRIBUTE_UNUSED)
1493 assemble_addr_to_section (symbol, dtors_section);
1495 #endif
1497 void
1498 default_named_section_asm_out_constructor (rtx symbol, int priority)
1500 section *sec;
1502 if (priority != DEFAULT_INIT_PRIORITY)
1503 sec = get_cdtor_priority_section (priority,
1504 /*constructor_p=*/true);
1505 else
1506 sec = get_section (".ctors", SECTION_WRITE, NULL);
1508 assemble_addr_to_section (symbol, sec);
1511 #ifdef CTORS_SECTION_ASM_OP
1512 void
1513 default_ctor_section_asm_out_constructor (rtx symbol,
1514 int priority ATTRIBUTE_UNUSED)
1516 assemble_addr_to_section (symbol, ctors_section);
1518 #endif
1520 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1521 a nonzero value if the constant pool should be output before the
1522 start of the function, or a zero value if the pool should output
1523 after the end of the function. The default is to put it before the
1524 start. */
1526 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1527 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1528 #endif
1530 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1531 to be output to assembler.
1532 Set first_global_object_name and weak_global_object_name as appropriate. */
1534 void
1535 notice_global_symbol (tree decl)
1537 const char **type = &first_global_object_name;
1539 if (first_global_object_name
1540 || !TREE_PUBLIC (decl)
1541 || DECL_EXTERNAL (decl)
1542 || !DECL_NAME (decl)
1543 || (TREE_CODE (decl) != FUNCTION_DECL
1544 && (TREE_CODE (decl) != VAR_DECL
1545 || (DECL_COMMON (decl)
1546 && (DECL_INITIAL (decl) == 0
1547 || DECL_INITIAL (decl) == error_mark_node))))
1548 || !MEM_P (DECL_RTL (decl)))
1549 return;
1551 /* We win when global object is found, but it is useful to know about weak
1552 symbol as well so we can produce nicer unique names. */
1553 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl) || flag_shlib)
1554 type = &weak_global_object_name;
1556 if (!*type)
1558 const char *p;
1559 const char *name;
1560 rtx decl_rtl = DECL_RTL (decl);
1562 p = targetm.strip_name_encoding (XSTR (XEXP (decl_rtl, 0), 0));
1563 name = ggc_strdup (p);
1565 *type = name;
1569 /* If not using flag_reorder_blocks_and_partition, decide early whether the
1570 current function goes into the cold section, so that targets can use
1571 current_function_section during RTL expansion. DECL describes the
1572 function. */
1574 void
1575 decide_function_section (tree decl)
1577 first_function_block_is_cold = false;
1579 if (flag_reorder_blocks_and_partition)
1580 /* We will decide in assemble_start_function. */
1581 return;
1583 if (DECL_SECTION_NAME (decl))
1585 struct cgraph_node *node = cgraph_get_node (current_function_decl);
1586 /* Calls to function_section rely on first_function_block_is_cold
1587 being accurate. */
1588 first_function_block_is_cold = (node
1589 && node->frequency
1590 == NODE_FREQUENCY_UNLIKELY_EXECUTED);
1593 in_cold_section_p = first_function_block_is_cold;
1596 /* Output assembler code for the constant pool of a function and associated
1597 with defining the name of the function. DECL describes the function.
1598 NAME is the function's name. For the constant pool, we use the current
1599 constant pool data. */
1601 void
1602 assemble_start_function (tree decl, const char *fnname)
1604 int align;
1605 char tmp_label[100];
1606 bool hot_label_written = false;
1608 if (flag_reorder_blocks_and_partition)
1610 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTB", const_labelno);
1611 crtl->subsections.hot_section_label = ggc_strdup (tmp_label);
1612 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDB", const_labelno);
1613 crtl->subsections.cold_section_label = ggc_strdup (tmp_label);
1614 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTE", const_labelno);
1615 crtl->subsections.hot_section_end_label = ggc_strdup (tmp_label);
1616 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDE", const_labelno);
1617 crtl->subsections.cold_section_end_label = ggc_strdup (tmp_label);
1618 const_labelno++;
1620 else
1622 crtl->subsections.hot_section_label = NULL;
1623 crtl->subsections.cold_section_label = NULL;
1624 crtl->subsections.hot_section_end_label = NULL;
1625 crtl->subsections.cold_section_end_label = NULL;
1628 /* The following code does not need preprocessing in the assembler. */
1630 app_disable ();
1632 if (CONSTANT_POOL_BEFORE_FUNCTION)
1633 output_constant_pool (fnname, decl);
1635 /* Make sure the not and cold text (code) sections are properly
1636 aligned. This is necessary here in the case where the function
1637 has both hot and cold sections, because we don't want to re-set
1638 the alignment when the section switch happens mid-function. */
1640 if (flag_reorder_blocks_and_partition)
1642 first_function_block_is_cold = false;
1644 switch_to_section (unlikely_text_section ());
1645 assemble_align (DECL_ALIGN (decl));
1646 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_label);
1648 /* When the function starts with a cold section, we need to explicitly
1649 align the hot section and write out the hot section label.
1650 But if the current function is a thunk, we do not have a CFG. */
1651 if (!cfun->is_thunk
1652 && BB_PARTITION (ENTRY_BLOCK_PTR_FOR_FN (cfun)->next_bb) == BB_COLD_PARTITION)
1654 switch_to_section (text_section);
1655 assemble_align (DECL_ALIGN (decl));
1656 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1657 hot_label_written = true;
1658 first_function_block_is_cold = true;
1660 in_cold_section_p = first_function_block_is_cold;
1664 /* Switch to the correct text section for the start of the function. */
1666 switch_to_section (function_section (decl));
1667 if (flag_reorder_blocks_and_partition
1668 && !hot_label_written)
1669 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1671 /* Tell assembler to move to target machine's alignment for functions. */
1672 align = floor_log2 (DECL_ALIGN (decl) / BITS_PER_UNIT);
1673 if (align > 0)
1675 ASM_OUTPUT_ALIGN (asm_out_file, align);
1678 /* Handle a user-specified function alignment.
1679 Note that we still need to align to DECL_ALIGN, as above,
1680 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1681 if (! DECL_USER_ALIGN (decl)
1682 && align_functions_log > align
1683 && optimize_function_for_speed_p (cfun))
1685 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1686 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1687 align_functions_log, align_functions - 1);
1688 #else
1689 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1690 #endif
1693 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1694 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1695 #endif
1697 if (!DECL_IGNORED_P (decl))
1698 (*debug_hooks->begin_function) (decl);
1700 /* Make function name accessible from other files, if appropriate. */
1702 if (TREE_PUBLIC (decl))
1704 notice_global_symbol (decl);
1706 globalize_decl (decl);
1708 maybe_assemble_visibility (decl);
1711 if (DECL_PRESERVE_P (decl))
1712 targetm.asm_out.mark_decl_preserved (fnname);
1714 /* Do any machine/system dependent processing of the function name. */
1715 #ifdef ASM_DECLARE_FUNCTION_NAME
1716 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1717 #else
1718 /* Standard thing is just output label for the function. */
1719 ASM_OUTPUT_FUNCTION_LABEL (asm_out_file, fnname, current_function_decl);
1720 #endif /* ASM_DECLARE_FUNCTION_NAME */
1722 if (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (decl)))
1723 saw_no_split_stack = true;
1726 /* Output assembler code associated with defining the size of the
1727 function. DECL describes the function. NAME is the function's name. */
1729 void
1730 assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED)
1732 #ifdef ASM_DECLARE_FUNCTION_SIZE
1733 /* We could have switched section in the middle of the function. */
1734 if (flag_reorder_blocks_and_partition)
1735 switch_to_section (function_section (decl));
1736 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1737 #endif
1738 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1740 output_constant_pool (fnname, decl);
1741 switch_to_section (function_section (decl)); /* need to switch back */
1743 /* Output labels for end of hot/cold text sections (to be used by
1744 debug info.) */
1745 if (flag_reorder_blocks_and_partition)
1747 section *save_text_section;
1749 save_text_section = in_section;
1750 switch_to_section (unlikely_text_section ());
1751 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label);
1752 if (first_function_block_is_cold)
1753 switch_to_section (text_section);
1754 else
1755 switch_to_section (function_section (decl));
1756 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label);
1757 switch_to_section (save_text_section);
1761 /* Assemble code to leave SIZE bytes of zeros. */
1763 void
1764 assemble_zeros (unsigned HOST_WIDE_INT size)
1766 /* Do no output if -fsyntax-only. */
1767 if (flag_syntax_only)
1768 return;
1770 #ifdef ASM_NO_SKIP_IN_TEXT
1771 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1772 so we must output 0s explicitly in the text section. */
1773 if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0)
1775 unsigned HOST_WIDE_INT i;
1776 for (i = 0; i < size; i++)
1777 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1779 else
1780 #endif
1781 if (size > 0)
1782 ASM_OUTPUT_SKIP (asm_out_file, size);
1785 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1787 void
1788 assemble_align (int align)
1790 if (align > BITS_PER_UNIT)
1792 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1796 /* Assemble a string constant with the specified C string as contents. */
1798 void
1799 assemble_string (const char *p, int size)
1801 int pos = 0;
1802 int maximum = 2000;
1804 /* If the string is very long, split it up. */
1806 while (pos < size)
1808 int thissize = size - pos;
1809 if (thissize > maximum)
1810 thissize = maximum;
1812 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1814 pos += thissize;
1815 p += thissize;
1820 /* A noswitch_section_callback for lcomm_section. */
1822 static bool
1823 emit_local (tree decl ATTRIBUTE_UNUSED,
1824 const char *name ATTRIBUTE_UNUSED,
1825 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1826 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1828 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1829 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name,
1830 size, DECL_ALIGN (decl));
1831 return true;
1832 #elif defined ASM_OUTPUT_ALIGNED_LOCAL
1833 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, DECL_ALIGN (decl));
1834 return true;
1835 #else
1836 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1837 return false;
1838 #endif
1841 /* A noswitch_section_callback for bss_noswitch_section. */
1843 #if defined ASM_OUTPUT_ALIGNED_BSS
1844 static bool
1845 emit_bss (tree decl ATTRIBUTE_UNUSED,
1846 const char *name ATTRIBUTE_UNUSED,
1847 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1848 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1850 #if defined ASM_OUTPUT_ALIGNED_BSS
1851 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size,
1852 get_variable_align (decl));
1853 return true;
1854 #endif
1856 #endif
1858 /* A noswitch_section_callback for comm_section. */
1860 static bool
1861 emit_common (tree decl ATTRIBUTE_UNUSED,
1862 const char *name ATTRIBUTE_UNUSED,
1863 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1864 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1866 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1867 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name,
1868 size, get_variable_align (decl));
1869 return true;
1870 #elif defined ASM_OUTPUT_ALIGNED_COMMON
1871 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size,
1872 get_variable_align (decl));
1873 return true;
1874 #else
1875 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
1876 return false;
1877 #endif
1880 /* A noswitch_section_callback for tls_comm_section. */
1882 static bool
1883 emit_tls_common (tree decl ATTRIBUTE_UNUSED,
1884 const char *name ATTRIBUTE_UNUSED,
1885 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1886 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1888 #ifdef ASM_OUTPUT_TLS_COMMON
1889 ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size);
1890 return true;
1891 #else
1892 sorry ("thread-local COMMON data not implemented");
1893 return true;
1894 #endif
1897 /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT.
1898 NAME is the name of DECL's SYMBOL_REF. */
1900 static void
1901 assemble_noswitch_variable (tree decl, const char *name, section *sect,
1902 unsigned int align)
1904 unsigned HOST_WIDE_INT size, rounded;
1906 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
1907 rounded = size;
1909 if ((flag_sanitize & SANITIZE_ADDRESS) && asan_protect_global (decl))
1910 size += asan_red_zone_size (size);
1912 /* Don't allocate zero bytes of common,
1913 since that means "undefined external" in the linker. */
1914 if (size == 0)
1915 rounded = 1;
1917 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1918 so that each uninitialized object starts on such a boundary. */
1919 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
1920 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1921 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1923 if (!sect->noswitch.callback (decl, name, size, rounded)
1924 && (unsigned HOST_WIDE_INT) (align / BITS_PER_UNIT) > rounded)
1925 error ("requested alignment for %q+D is greater than "
1926 "implemented alignment of %wu", decl, rounded);
1929 /* A subroutine of assemble_variable. Output the label and contents of
1930 DECL, whose address is a SYMBOL_REF with name NAME. DONT_OUTPUT_DATA
1931 is as for assemble_variable. */
1933 static void
1934 assemble_variable_contents (tree decl, const char *name,
1935 bool dont_output_data)
1937 /* Do any machine/system dependent processing of the object. */
1938 #ifdef ASM_DECLARE_OBJECT_NAME
1939 last_assemble_variable_decl = decl;
1940 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
1941 #else
1942 /* Standard thing is just output label for the object. */
1943 ASM_OUTPUT_LABEL (asm_out_file, name);
1944 #endif /* ASM_DECLARE_OBJECT_NAME */
1946 if (!dont_output_data)
1948 if (DECL_INITIAL (decl)
1949 && DECL_INITIAL (decl) != error_mark_node
1950 && !initializer_zerop (DECL_INITIAL (decl)))
1951 /* Output the actual data. */
1952 output_constant (DECL_INITIAL (decl),
1953 tree_to_uhwi (DECL_SIZE_UNIT (decl)),
1954 get_variable_align (decl));
1955 else
1956 /* Leave space for it. */
1957 assemble_zeros (tree_to_uhwi (DECL_SIZE_UNIT (decl)));
1961 /* Assemble everything that is needed for a variable or function declaration.
1962 Not used for automatic variables, and not used for function definitions.
1963 Should not be called for variables of incomplete structure type.
1965 TOP_LEVEL is nonzero if this variable has file scope.
1966 AT_END is nonzero if this is the special handling, at end of compilation,
1967 to define things that have had only tentative definitions.
1968 DONT_OUTPUT_DATA if nonzero means don't actually output the
1969 initial value (that will be done by the caller). */
1971 void
1972 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
1973 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
1975 const char *name;
1976 rtx decl_rtl, symbol;
1977 section *sect;
1978 unsigned int align;
1979 bool asan_protected = false;
1981 /* This function is supposed to handle VARIABLES. Ensure we have one. */
1982 gcc_assert (TREE_CODE (decl) == VAR_DECL);
1984 /* Emulated TLS had better not get this far. */
1985 gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl));
1987 last_assemble_variable_decl = 0;
1989 /* Normally no need to say anything here for external references,
1990 since assemble_external is called by the language-specific code
1991 when a declaration is first seen. */
1993 if (DECL_EXTERNAL (decl))
1994 return;
1996 /* Do nothing for global register variables. */
1997 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
1999 TREE_ASM_WRITTEN (decl) = 1;
2000 return;
2003 /* If type was incomplete when the variable was declared,
2004 see if it is complete now. */
2006 if (DECL_SIZE (decl) == 0)
2007 layout_decl (decl, 0);
2009 /* Still incomplete => don't allocate it; treat the tentative defn
2010 (which is what it must have been) as an `extern' reference. */
2012 if (!dont_output_data && DECL_SIZE (decl) == 0)
2014 error ("storage size of %q+D isn%'t known", decl);
2015 TREE_ASM_WRITTEN (decl) = 1;
2016 return;
2019 /* The first declaration of a variable that comes through this function
2020 decides whether it is global (in C, has external linkage)
2021 or local (in C, has internal linkage). So do nothing more
2022 if this function has already run. */
2024 if (TREE_ASM_WRITTEN (decl))
2025 return;
2027 /* Make sure targetm.encode_section_info is invoked before we set
2028 ASM_WRITTEN. */
2029 decl_rtl = DECL_RTL (decl);
2031 TREE_ASM_WRITTEN (decl) = 1;
2033 /* Do no output if -fsyntax-only. */
2034 if (flag_syntax_only)
2035 return;
2037 if (! dont_output_data
2038 && ! valid_constant_size_p (DECL_SIZE_UNIT (decl)))
2040 error ("size of variable %q+D is too large", decl);
2041 return;
2044 gcc_assert (MEM_P (decl_rtl));
2045 gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF);
2046 symbol = XEXP (decl_rtl, 0);
2048 /* If this symbol belongs to the tree constant pool, output the constant
2049 if it hasn't already been written. */
2050 if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
2052 tree decl = SYMBOL_REF_DECL (symbol);
2053 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
2054 output_constant_def_contents (symbol);
2055 return;
2058 app_disable ();
2060 name = XSTR (symbol, 0);
2061 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
2062 notice_global_symbol (decl);
2064 /* Compute the alignment of this data. */
2066 align_variable (decl, dont_output_data);
2068 if ((flag_sanitize & SANITIZE_ADDRESS)
2069 && asan_protect_global (decl))
2071 asan_protected = true;
2072 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
2073 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
2076 set_mem_align (decl_rtl, DECL_ALIGN (decl));
2078 align = get_variable_align (decl);
2080 if (TREE_PUBLIC (decl))
2081 maybe_assemble_visibility (decl);
2083 if (DECL_PRESERVE_P (decl))
2084 targetm.asm_out.mark_decl_preserved (name);
2086 /* First make the assembler name(s) global if appropriate. */
2087 sect = get_variable_section (decl, false);
2088 if (TREE_PUBLIC (decl)
2089 && (sect->common.flags & SECTION_COMMON) == 0)
2090 globalize_decl (decl);
2092 /* Output any data that we will need to use the address of. */
2093 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
2094 output_addressed_constants (DECL_INITIAL (decl));
2096 /* dbxout.c needs to know this. */
2097 if (sect && (sect->common.flags & SECTION_CODE) != 0)
2098 DECL_IN_TEXT_SECTION (decl) = 1;
2100 /* If the decl is part of an object_block, make sure that the decl
2101 has been positioned within its block, but do not write out its
2102 definition yet. output_object_blocks will do that later. */
2103 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
2105 gcc_assert (!dont_output_data);
2106 place_block_symbol (symbol);
2108 else if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
2109 assemble_noswitch_variable (decl, name, sect, align);
2110 else
2112 /* The following bit of code ensures that vtable_map
2113 variables are not only in the comdat section, but that
2114 each variable has its own unique comdat name. If this
2115 code is removed, the variables end up in the same section
2116 with a single comdat name.
2118 FIXME: resolve_unique_section needs to deal better with
2119 decls with both DECL_SECTION_NAME and DECL_ONE_ONLY. Once
2120 that is fixed, this if-else statement can be replaced with
2121 a single call to "switch_to_section (sect)". */
2122 if (sect->named.name
2123 && (strcmp (sect->named.name, ".vtable_map_vars") == 0))
2125 #if defined (OBJECT_FORMAT_ELF)
2126 targetm.asm_out.named_section (sect->named.name,
2127 sect->named.common.flags
2128 | SECTION_LINKONCE,
2129 DECL_NAME (decl));
2130 in_section = sect;
2131 #else
2132 switch_to_section (sect);
2133 #endif
2135 else
2136 switch_to_section (sect);
2137 if (align > BITS_PER_UNIT)
2138 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2139 assemble_variable_contents (decl, name, dont_output_data);
2140 if (asan_protected)
2142 unsigned HOST_WIDE_INT int size
2143 = tree_to_uhwi (DECL_SIZE_UNIT (decl));
2144 assemble_zeros (asan_red_zone_size (size));
2150 /* Given a function declaration (FN_DECL), this function assembles the
2151 function into the .preinit_array section. */
2153 void
2154 assemble_vtv_preinit_initializer (tree fn_decl)
2156 section *sect;
2157 unsigned flags = SECTION_WRITE;
2158 rtx symbol = XEXP (DECL_RTL (fn_decl), 0);
2160 flags |= SECTION_NOTYPE;
2161 sect = get_section (".preinit_array", flags, fn_decl);
2162 switch_to_section (sect);
2163 assemble_addr_to_section (symbol, sect);
2166 /* Return 1 if type TYPE contains any pointers. */
2168 static int
2169 contains_pointers_p (tree type)
2171 switch (TREE_CODE (type))
2173 case POINTER_TYPE:
2174 case REFERENCE_TYPE:
2175 /* I'm not sure whether OFFSET_TYPE needs this treatment,
2176 so I'll play safe and return 1. */
2177 case OFFSET_TYPE:
2178 return 1;
2180 case RECORD_TYPE:
2181 case UNION_TYPE:
2182 case QUAL_UNION_TYPE:
2184 tree fields;
2185 /* For a type that has fields, see if the fields have pointers. */
2186 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2187 if (TREE_CODE (fields) == FIELD_DECL
2188 && contains_pointers_p (TREE_TYPE (fields)))
2189 return 1;
2190 return 0;
2193 case ARRAY_TYPE:
2194 /* An array type contains pointers if its element type does. */
2195 return contains_pointers_p (TREE_TYPE (type));
2197 default:
2198 return 0;
2202 /* We delay assemble_external processing until
2203 the compilation unit is finalized. This is the best we can do for
2204 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2205 it all the way to final. See PR 17982 for further discussion. */
2206 static GTY(()) tree pending_assemble_externals;
2208 #ifdef ASM_OUTPUT_EXTERNAL
2209 /* Some targets delay some output to final using TARGET_ASM_FILE_END.
2210 As a result, assemble_external can be called after the list of externals
2211 is processed and the pointer set destroyed. */
2212 static bool pending_assemble_externals_processed;
2214 /* Avoid O(external_decls**2) lookups in the pending_assemble_externals
2215 TREE_LIST in assemble_external. */
2216 static struct pointer_set_t *pending_assemble_externals_set;
2218 /* True if DECL is a function decl for which no out-of-line copy exists.
2219 It is assumed that DECL's assembler name has been set. */
2221 static bool
2222 incorporeal_function_p (tree decl)
2224 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
2226 const char *name;
2228 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2229 && (DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA
2230 || DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA_WITH_ALIGN))
2231 return true;
2233 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2234 /* Atomic or sync builtins which have survived this far will be
2235 resolved externally and therefore are not incorporeal. */
2236 if (strncmp (name, "__builtin_", 10) == 0)
2237 return true;
2239 return false;
2242 /* Actually do the tests to determine if this is necessary, and invoke
2243 ASM_OUTPUT_EXTERNAL. */
2244 static void
2245 assemble_external_real (tree decl)
2247 rtx rtl = DECL_RTL (decl);
2249 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2250 && !SYMBOL_REF_USED (XEXP (rtl, 0))
2251 && !incorporeal_function_p (decl))
2253 /* Some systems do require some output. */
2254 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2255 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2258 #endif
2260 void
2261 process_pending_assemble_externals (void)
2263 #ifdef ASM_OUTPUT_EXTERNAL
2264 tree list;
2265 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2266 assemble_external_real (TREE_VALUE (list));
2268 pending_assemble_externals = 0;
2269 pending_assemble_externals_processed = true;
2270 pointer_set_destroy (pending_assemble_externals_set);
2271 #endif
2274 /* This TREE_LIST contains any weak symbol declarations waiting
2275 to be emitted. */
2276 static GTY(()) tree weak_decls;
2278 /* Output something to declare an external symbol to the assembler,
2279 and qualifiers such as weakness. (Most assemblers don't need
2280 extern declaration, so we normally output nothing.) Do nothing if
2281 DECL is not external. */
2283 void
2284 assemble_external (tree decl ATTRIBUTE_UNUSED)
2286 /* Make sure that the ASM_OUT_FILE is open.
2287 If it's not, we should not be calling this function. */
2288 gcc_assert (asm_out_file);
2290 /* In a perfect world, the following condition would be true.
2291 Sadly, the Java and Go front ends emit assembly *from the front end*,
2292 bypassing the call graph. See PR52739. Fix before GCC 4.8. */
2293 #if 0
2294 /* This function should only be called if we are expanding, or have
2295 expanded, to RTL.
2296 Ideally, only final.c would be calling this function, but it is
2297 not clear whether that would break things somehow. See PR 17982
2298 for further discussion. */
2299 gcc_assert (cgraph_state == CGRAPH_STATE_EXPANSION
2300 || cgraph_state == CGRAPH_STATE_FINISHED);
2301 #endif
2303 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2304 return;
2306 /* We want to output annotation for weak and external symbols at
2307 very last to check if they are references or not. */
2309 if (TARGET_SUPPORTS_WEAK
2310 && DECL_WEAK (decl)
2311 /* TREE_STATIC is a weird and abused creature which is not
2312 generally the right test for whether an entity has been
2313 locally emitted, inlined or otherwise not-really-extern, but
2314 for declarations that can be weak, it happens to be
2315 match. */
2316 && !TREE_STATIC (decl)
2317 && lookup_attribute ("weak", DECL_ATTRIBUTES (decl))
2318 && value_member (decl, weak_decls) == NULL_TREE)
2319 weak_decls = tree_cons (NULL, decl, weak_decls);
2321 #ifdef ASM_OUTPUT_EXTERNAL
2322 if (pending_assemble_externals_processed)
2324 assemble_external_real (decl);
2325 return;
2328 if (! pointer_set_insert (pending_assemble_externals_set, decl))
2329 pending_assemble_externals = tree_cons (NULL, decl,
2330 pending_assemble_externals);
2331 #endif
2334 /* Similar, for calling a library function FUN. */
2336 void
2337 assemble_external_libcall (rtx fun)
2339 /* Declare library function name external when first used, if nec. */
2340 if (! SYMBOL_REF_USED (fun))
2342 SYMBOL_REF_USED (fun) = 1;
2343 targetm.asm_out.external_libcall (fun);
2347 /* Assemble a label named NAME. */
2349 void
2350 assemble_label (FILE *file, const char *name)
2352 ASM_OUTPUT_LABEL (file, name);
2355 /* Set the symbol_referenced flag for ID. */
2356 void
2357 mark_referenced (tree id)
2359 TREE_SYMBOL_REFERENCED (id) = 1;
2362 /* Set the symbol_referenced flag for DECL and notify callgraph. */
2363 void
2364 mark_decl_referenced (tree decl)
2366 if (TREE_CODE (decl) == FUNCTION_DECL)
2368 /* Extern inline functions don't become needed when referenced.
2369 If we know a method will be emitted in other TU and no new
2370 functions can be marked reachable, just use the external
2371 definition. */
2372 struct cgraph_node *node = cgraph_get_create_node (decl);
2373 if (!DECL_EXTERNAL (decl)
2374 && !node->definition)
2375 cgraph_mark_force_output_node (node);
2377 else if (TREE_CODE (decl) == VAR_DECL)
2379 varpool_node *node = varpool_node_for_decl (decl);
2380 /* C++ frontend use mark_decl_references to force COMDAT variables
2381 to be output that might appear dead otherwise. */
2382 node->force_output = true;
2384 /* else do nothing - we can get various sorts of CST nodes here,
2385 which do not need to be marked. */
2389 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS
2390 until we find an identifier that is not itself a transparent alias.
2391 Modify the alias passed to it by reference (and all aliases on the
2392 way to the ultimate target), such that they do not have to be
2393 followed again, and return the ultimate target of the alias
2394 chain. */
2396 static inline tree
2397 ultimate_transparent_alias_target (tree *alias)
2399 tree target = *alias;
2401 if (IDENTIFIER_TRANSPARENT_ALIAS (target))
2403 gcc_assert (TREE_CHAIN (target));
2404 target = ultimate_transparent_alias_target (&TREE_CHAIN (target));
2405 gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target)
2406 && ! TREE_CHAIN (target));
2407 *alias = target;
2410 return target;
2413 /* Output to FILE (an assembly file) a reference to NAME. If NAME
2414 starts with a *, the rest of NAME is output verbatim. Otherwise
2415 NAME is transformed in a target-specific way (usually by the
2416 addition of an underscore). */
2418 void
2419 assemble_name_raw (FILE *file, const char *name)
2421 if (name[0] == '*')
2422 fputs (&name[1], file);
2423 else
2424 ASM_OUTPUT_LABELREF (file, name);
2427 /* Like assemble_name_raw, but should be used when NAME might refer to
2428 an entity that is also represented as a tree (like a function or
2429 variable). If NAME does refer to such an entity, that entity will
2430 be marked as referenced. */
2432 void
2433 assemble_name (FILE *file, const char *name)
2435 const char *real_name;
2436 tree id;
2438 real_name = targetm.strip_name_encoding (name);
2440 id = maybe_get_identifier (real_name);
2441 if (id)
2443 tree id_orig = id;
2445 mark_referenced (id);
2446 ultimate_transparent_alias_target (&id);
2447 if (id != id_orig)
2448 name = IDENTIFIER_POINTER (id);
2449 gcc_assert (! TREE_CHAIN (id));
2452 assemble_name_raw (file, name);
2455 /* Allocate SIZE bytes writable static space with a gensym name
2456 and return an RTX to refer to its address. */
2459 assemble_static_space (unsigned HOST_WIDE_INT size)
2461 char name[12];
2462 const char *namestring;
2463 rtx x;
2465 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2466 ++const_labelno;
2467 namestring = ggc_strdup (name);
2469 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2470 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2472 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2473 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2474 BIGGEST_ALIGNMENT);
2475 #else
2476 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2477 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2478 #else
2480 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2481 so that each uninitialized object starts on such a boundary. */
2482 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2483 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2484 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2485 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2486 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2487 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2489 #endif
2490 #endif
2491 return x;
2494 /* Assemble the static constant template for function entry trampolines.
2495 This is done at most once per compilation.
2496 Returns an RTX for the address of the template. */
2498 static GTY(()) rtx initial_trampoline;
2501 assemble_trampoline_template (void)
2503 char label[256];
2504 const char *name;
2505 int align;
2506 rtx symbol;
2508 gcc_assert (targetm.asm_out.trampoline_template != NULL);
2510 if (initial_trampoline)
2511 return initial_trampoline;
2513 /* By default, put trampoline templates in read-only data section. */
2515 #ifdef TRAMPOLINE_SECTION
2516 switch_to_section (TRAMPOLINE_SECTION);
2517 #else
2518 switch_to_section (readonly_data_section);
2519 #endif
2521 /* Write the assembler code to define one. */
2522 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2523 if (align > 0)
2524 ASM_OUTPUT_ALIGN (asm_out_file, align);
2526 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2527 targetm.asm_out.trampoline_template (asm_out_file);
2529 /* Record the rtl to refer to it. */
2530 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2531 name = ggc_strdup (label);
2532 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2533 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2535 initial_trampoline = gen_const_mem (BLKmode, symbol);
2536 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2537 set_mem_size (initial_trampoline, TRAMPOLINE_SIZE);
2539 return initial_trampoline;
2542 /* A and B are either alignments or offsets. Return the minimum alignment
2543 that may be assumed after adding the two together. */
2545 static inline unsigned
2546 min_align (unsigned int a, unsigned int b)
2548 return (a | b) & -(a | b);
2551 /* Return the assembler directive for creating a given kind of integer
2552 object. SIZE is the number of bytes in the object and ALIGNED_P
2553 indicates whether it is known to be aligned. Return NULL if the
2554 assembly dialect has no such directive.
2556 The returned string should be printed at the start of a new line and
2557 be followed immediately by the object's initial value. */
2559 const char *
2560 integer_asm_op (int size, int aligned_p)
2562 struct asm_int_op *ops;
2564 if (aligned_p)
2565 ops = &targetm.asm_out.aligned_op;
2566 else
2567 ops = &targetm.asm_out.unaligned_op;
2569 switch (size)
2571 case 1:
2572 return targetm.asm_out.byte_op;
2573 case 2:
2574 return ops->hi;
2575 case 4:
2576 return ops->si;
2577 case 8:
2578 return ops->di;
2579 case 16:
2580 return ops->ti;
2581 default:
2582 return NULL;
2586 /* Use directive OP to assemble an integer object X. Print OP at the
2587 start of the line, followed immediately by the value of X. */
2589 void
2590 assemble_integer_with_op (const char *op, rtx x)
2592 fputs (op, asm_out_file);
2593 output_addr_const (asm_out_file, x);
2594 fputc ('\n', asm_out_file);
2597 /* The default implementation of the asm_out.integer target hook. */
2599 bool
2600 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2601 unsigned int size ATTRIBUTE_UNUSED,
2602 int aligned_p ATTRIBUTE_UNUSED)
2604 const char *op = integer_asm_op (size, aligned_p);
2605 /* Avoid GAS bugs for large values. Specifically negative values whose
2606 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2607 if (size > UNITS_PER_WORD && size > POINTER_SIZE / BITS_PER_UNIT)
2608 return false;
2609 return op && (assemble_integer_with_op (op, x), true);
2612 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2613 the alignment of the integer in bits. Return 1 if we were able to output
2614 the constant, otherwise 0. We must be able to output the constant,
2615 if FORCE is nonzero. */
2617 bool
2618 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2620 int aligned_p;
2622 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2624 /* See if the target hook can handle this kind of object. */
2625 if (targetm.asm_out.integer (x, size, aligned_p))
2626 return true;
2628 /* If the object is a multi-byte one, try splitting it up. Split
2629 it into words it if is multi-word, otherwise split it into bytes. */
2630 if (size > 1)
2632 enum machine_mode omode, imode;
2633 unsigned int subalign;
2634 unsigned int subsize, i;
2635 enum mode_class mclass;
2637 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2638 subalign = MIN (align, subsize * BITS_PER_UNIT);
2639 if (GET_CODE (x) == CONST_FIXED)
2640 mclass = GET_MODE_CLASS (GET_MODE (x));
2641 else
2642 mclass = MODE_INT;
2644 omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0);
2645 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0);
2647 for (i = 0; i < size; i += subsize)
2649 rtx partial = simplify_subreg (omode, x, imode, i);
2650 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2651 break;
2653 if (i == size)
2654 return true;
2656 /* If we've printed some of it, but not all of it, there's no going
2657 back now. */
2658 gcc_assert (!i);
2661 gcc_assert (!force);
2663 return false;
2666 void
2667 assemble_real (REAL_VALUE_TYPE d, enum machine_mode mode, unsigned int align)
2669 long data[4] = {0, 0, 0, 0};
2670 int i;
2671 int bitsize, nelts, nunits, units_per;
2673 /* This is hairy. We have a quantity of known size. real_to_target
2674 will put it into an array of *host* longs, 32 bits per element
2675 (even if long is more than 32 bits). We need to determine the
2676 number of array elements that are occupied (nelts) and the number
2677 of *target* min-addressable units that will be occupied in the
2678 object file (nunits). We cannot assume that 32 divides the
2679 mode's bitsize (size * BITS_PER_UNIT) evenly.
2681 size * BITS_PER_UNIT is used here to make sure that padding bits
2682 (which might appear at either end of the value; real_to_target
2683 will include the padding bits in its output array) are included. */
2685 nunits = GET_MODE_SIZE (mode);
2686 bitsize = nunits * BITS_PER_UNIT;
2687 nelts = CEIL (bitsize, 32);
2688 units_per = 32 / BITS_PER_UNIT;
2690 real_to_target (data, &d, mode);
2692 /* Put out the first word with the specified alignment. */
2693 assemble_integer (GEN_INT (data[0]), MIN (nunits, units_per), align, 1);
2694 nunits -= units_per;
2696 /* Subsequent words need only 32-bit alignment. */
2697 align = min_align (align, 32);
2699 for (i = 1; i < nelts; i++)
2701 assemble_integer (GEN_INT (data[i]), MIN (nunits, units_per), align, 1);
2702 nunits -= units_per;
2706 /* Given an expression EXP with a constant value,
2707 reduce it to the sum of an assembler symbol and an integer.
2708 Store them both in the structure *VALUE.
2709 EXP must be reducible. */
2711 struct addr_const {
2712 rtx base;
2713 HOST_WIDE_INT offset;
2716 static void
2717 decode_addr_const (tree exp, struct addr_const *value)
2719 tree target = TREE_OPERAND (exp, 0);
2720 int offset = 0;
2721 rtx x;
2723 while (1)
2725 if (TREE_CODE (target) == COMPONENT_REF
2726 && tree_fits_shwi_p (byte_position (TREE_OPERAND (target, 1))))
2728 offset += int_byte_position (TREE_OPERAND (target, 1));
2729 target = TREE_OPERAND (target, 0);
2731 else if (TREE_CODE (target) == ARRAY_REF
2732 || TREE_CODE (target) == ARRAY_RANGE_REF)
2734 offset += (tree_to_uhwi (TYPE_SIZE_UNIT (TREE_TYPE (target)))
2735 * tree_to_shwi (TREE_OPERAND (target, 1)));
2736 target = TREE_OPERAND (target, 0);
2738 else if (TREE_CODE (target) == MEM_REF
2739 && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR)
2741 offset += mem_ref_offset (target).low;
2742 target = TREE_OPERAND (TREE_OPERAND (target, 0), 0);
2744 else if (TREE_CODE (target) == INDIRECT_REF
2745 && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR
2746 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0))
2747 == ADDR_EXPR)
2748 target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0);
2749 else
2750 break;
2753 switch (TREE_CODE (target))
2755 case VAR_DECL:
2756 case FUNCTION_DECL:
2757 x = DECL_RTL (target);
2758 break;
2760 case LABEL_DECL:
2761 x = gen_rtx_MEM (FUNCTION_MODE,
2762 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2763 break;
2765 case REAL_CST:
2766 case FIXED_CST:
2767 case STRING_CST:
2768 case COMPLEX_CST:
2769 case CONSTRUCTOR:
2770 case INTEGER_CST:
2771 x = output_constant_def (target, 1);
2772 break;
2774 default:
2775 gcc_unreachable ();
2778 gcc_assert (MEM_P (x));
2779 x = XEXP (x, 0);
2781 value->base = x;
2782 value->offset = offset;
2786 static GTY((param_is (struct constant_descriptor_tree)))
2787 htab_t const_desc_htab;
2789 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2791 /* Constant pool accessor function. */
2793 htab_t
2794 constant_pool_htab (void)
2796 return const_desc_htab;
2799 /* Compute a hash code for a constant expression. */
2801 static hashval_t
2802 const_desc_hash (const void *ptr)
2804 return ((const struct constant_descriptor_tree *)ptr)->hash;
2807 static hashval_t
2808 const_hash_1 (const tree exp)
2810 const char *p;
2811 hashval_t hi;
2812 int len, i;
2813 enum tree_code code = TREE_CODE (exp);
2815 /* Either set P and LEN to the address and len of something to hash and
2816 exit the switch or return a value. */
2818 switch (code)
2820 case INTEGER_CST:
2821 p = (char *) &TREE_INT_CST (exp);
2822 len = sizeof TREE_INT_CST (exp);
2823 break;
2825 case REAL_CST:
2826 return real_hash (TREE_REAL_CST_PTR (exp));
2828 case FIXED_CST:
2829 return fixed_hash (TREE_FIXED_CST_PTR (exp));
2831 case STRING_CST:
2832 p = TREE_STRING_POINTER (exp);
2833 len = TREE_STRING_LENGTH (exp);
2834 break;
2836 case COMPLEX_CST:
2837 return (const_hash_1 (TREE_REALPART (exp)) * 5
2838 + const_hash_1 (TREE_IMAGPART (exp)));
2840 case VECTOR_CST:
2842 unsigned i;
2844 hi = 7 + VECTOR_CST_NELTS (exp);
2846 for (i = 0; i < VECTOR_CST_NELTS (exp); ++i)
2847 hi = hi * 563 + const_hash_1 (VECTOR_CST_ELT (exp, i));
2849 return hi;
2852 case CONSTRUCTOR:
2854 unsigned HOST_WIDE_INT idx;
2855 tree value;
2857 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2859 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
2860 if (value)
2861 hi = hi * 603 + const_hash_1 (value);
2863 return hi;
2866 case ADDR_EXPR:
2867 case FDESC_EXPR:
2869 struct addr_const value;
2871 decode_addr_const (exp, &value);
2872 switch (GET_CODE (value.base))
2874 case SYMBOL_REF:
2875 /* Don't hash the address of the SYMBOL_REF;
2876 only use the offset and the symbol name. */
2877 hi = value.offset;
2878 p = XSTR (value.base, 0);
2879 for (i = 0; p[i] != 0; i++)
2880 hi = ((hi * 613) + (unsigned) (p[i]));
2881 break;
2883 case LABEL_REF:
2884 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13;
2885 break;
2887 default:
2888 gcc_unreachable ();
2891 return hi;
2893 case PLUS_EXPR:
2894 case POINTER_PLUS_EXPR:
2895 case MINUS_EXPR:
2896 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2897 + const_hash_1 (TREE_OPERAND (exp, 1)));
2899 CASE_CONVERT:
2900 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
2902 default:
2903 /* A language specific constant. Just hash the code. */
2904 return code;
2907 /* Compute hashing function. */
2908 hi = len;
2909 for (i = 0; i < len; i++)
2910 hi = ((hi * 613) + (unsigned) (p[i]));
2912 return hi;
2915 /* Wrapper of compare_constant, for the htab interface. */
2916 static int
2917 const_desc_eq (const void *p1, const void *p2)
2919 const struct constant_descriptor_tree *const c1
2920 = (const struct constant_descriptor_tree *) p1;
2921 const struct constant_descriptor_tree *const c2
2922 = (const struct constant_descriptor_tree *) p2;
2923 if (c1->hash != c2->hash)
2924 return 0;
2925 return compare_constant (c1->value, c2->value);
2928 /* Compare t1 and t2, and return 1 only if they are known to result in
2929 the same bit pattern on output. */
2931 static int
2932 compare_constant (const tree t1, const tree t2)
2934 enum tree_code typecode;
2936 if (t1 == NULL_TREE)
2937 return t2 == NULL_TREE;
2938 if (t2 == NULL_TREE)
2939 return 0;
2941 if (TREE_CODE (t1) != TREE_CODE (t2))
2942 return 0;
2944 switch (TREE_CODE (t1))
2946 case INTEGER_CST:
2947 /* Integer constants are the same only if the same width of type. */
2948 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2949 return 0;
2950 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2951 return 0;
2952 return tree_int_cst_equal (t1, t2);
2954 case REAL_CST:
2955 /* Real constants are the same only if the same width of type. */
2956 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2957 return 0;
2959 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
2961 case FIXED_CST:
2962 /* Fixed constants are the same only if the same width of type. */
2963 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2964 return 0;
2966 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
2968 case STRING_CST:
2969 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2970 return 0;
2972 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
2973 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
2974 TREE_STRING_LENGTH (t1)));
2976 case COMPLEX_CST:
2977 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
2978 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
2980 case VECTOR_CST:
2982 unsigned i;
2984 if (VECTOR_CST_NELTS (t1) != VECTOR_CST_NELTS (t2))
2985 return 0;
2987 for (i = 0; i < VECTOR_CST_NELTS (t1); ++i)
2988 if (!compare_constant (VECTOR_CST_ELT (t1, i),
2989 VECTOR_CST_ELT (t2, i)))
2990 return 0;
2992 return 1;
2995 case CONSTRUCTOR:
2997 vec<constructor_elt, va_gc> *v1, *v2;
2998 unsigned HOST_WIDE_INT idx;
3000 typecode = TREE_CODE (TREE_TYPE (t1));
3001 if (typecode != TREE_CODE (TREE_TYPE (t2)))
3002 return 0;
3004 if (typecode == ARRAY_TYPE)
3006 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
3007 /* For arrays, check that the sizes all match. */
3008 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
3009 || size_1 == -1
3010 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
3011 return 0;
3013 else
3015 /* For record and union constructors, require exact type
3016 equality. */
3017 if (TREE_TYPE (t1) != TREE_TYPE (t2))
3018 return 0;
3021 v1 = CONSTRUCTOR_ELTS (t1);
3022 v2 = CONSTRUCTOR_ELTS (t2);
3023 if (vec_safe_length (v1) != vec_safe_length (v2))
3024 return 0;
3026 for (idx = 0; idx < vec_safe_length (v1); ++idx)
3028 constructor_elt *c1 = &(*v1)[idx];
3029 constructor_elt *c2 = &(*v2)[idx];
3031 /* Check that each value is the same... */
3032 if (!compare_constant (c1->value, c2->value))
3033 return 0;
3034 /* ... and that they apply to the same fields! */
3035 if (typecode == ARRAY_TYPE)
3037 if (!compare_constant (c1->index, c2->index))
3038 return 0;
3040 else
3042 if (c1->index != c2->index)
3043 return 0;
3047 return 1;
3050 case ADDR_EXPR:
3051 case FDESC_EXPR:
3053 struct addr_const value1, value2;
3054 enum rtx_code code;
3055 int ret;
3057 decode_addr_const (t1, &value1);
3058 decode_addr_const (t2, &value2);
3060 if (value1.offset != value2.offset)
3061 return 0;
3063 code = GET_CODE (value1.base);
3064 if (code != GET_CODE (value2.base))
3065 return 0;
3067 switch (code)
3069 case SYMBOL_REF:
3070 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3071 break;
3073 case LABEL_REF:
3074 ret = (CODE_LABEL_NUMBER (XEXP (value1.base, 0))
3075 == CODE_LABEL_NUMBER (XEXP (value2.base, 0)));
3076 break;
3078 default:
3079 gcc_unreachable ();
3081 return ret;
3084 case PLUS_EXPR:
3085 case POINTER_PLUS_EXPR:
3086 case MINUS_EXPR:
3087 case RANGE_EXPR:
3088 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3089 && compare_constant (TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3091 CASE_CONVERT:
3092 case VIEW_CONVERT_EXPR:
3093 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3095 default:
3096 return 0;
3099 gcc_unreachable ();
3102 /* Make a copy of the whole tree structure for a constant. This
3103 handles the same types of nodes that compare_constant handles. */
3105 static tree
3106 copy_constant (tree exp)
3108 switch (TREE_CODE (exp))
3110 case ADDR_EXPR:
3111 /* For ADDR_EXPR, we do not want to copy the decl whose address
3112 is requested. We do want to copy constants though. */
3113 if (CONSTANT_CLASS_P (TREE_OPERAND (exp, 0)))
3114 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
3115 copy_constant (TREE_OPERAND (exp, 0)));
3116 else
3117 return copy_node (exp);
3119 case INTEGER_CST:
3120 case REAL_CST:
3121 case FIXED_CST:
3122 case STRING_CST:
3123 return copy_node (exp);
3125 case COMPLEX_CST:
3126 return build_complex (TREE_TYPE (exp),
3127 copy_constant (TREE_REALPART (exp)),
3128 copy_constant (TREE_IMAGPART (exp)));
3130 case PLUS_EXPR:
3131 case POINTER_PLUS_EXPR:
3132 case MINUS_EXPR:
3133 return build2 (TREE_CODE (exp), TREE_TYPE (exp),
3134 copy_constant (TREE_OPERAND (exp, 0)),
3135 copy_constant (TREE_OPERAND (exp, 1)));
3137 CASE_CONVERT:
3138 case VIEW_CONVERT_EXPR:
3139 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
3140 copy_constant (TREE_OPERAND (exp, 0)));
3142 case VECTOR_CST:
3143 return build_vector (TREE_TYPE (exp), VECTOR_CST_ELTS (exp));
3145 case CONSTRUCTOR:
3147 tree copy = copy_node (exp);
3148 vec<constructor_elt, va_gc> *v;
3149 unsigned HOST_WIDE_INT idx;
3150 tree purpose, value;
3152 vec_alloc (v, vec_safe_length (CONSTRUCTOR_ELTS (exp)));
3153 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (exp), idx, purpose, value)
3155 constructor_elt ce = {purpose, copy_constant (value)};
3156 v->quick_push (ce);
3158 CONSTRUCTOR_ELTS (copy) = v;
3159 return copy;
3162 default:
3163 gcc_unreachable ();
3167 /* Return the section into which constant EXP should be placed. */
3169 static section *
3170 get_constant_section (tree exp, unsigned int align)
3172 return targetm.asm_out.select_section (exp,
3173 compute_reloc_for_constant (exp),
3174 align);
3177 /* Return the size of constant EXP in bytes. */
3179 static HOST_WIDE_INT
3180 get_constant_size (tree exp)
3182 HOST_WIDE_INT size;
3184 size = int_size_in_bytes (TREE_TYPE (exp));
3185 if (TREE_CODE (exp) == STRING_CST)
3186 size = MAX (TREE_STRING_LENGTH (exp), size);
3187 return size;
3190 /* Subroutine of output_constant_def:
3191 No constant equal to EXP is known to have been output.
3192 Make a constant descriptor to enter EXP in the hash table.
3193 Assign the label number and construct RTL to refer to the
3194 constant's location in memory.
3195 Caller is responsible for updating the hash table. */
3197 static struct constant_descriptor_tree *
3198 build_constant_desc (tree exp)
3200 struct constant_descriptor_tree *desc;
3201 rtx symbol, rtl;
3202 char label[256];
3203 int labelno;
3204 tree decl;
3206 desc = ggc_alloc_constant_descriptor_tree ();
3207 desc->value = copy_constant (exp);
3209 /* Create a string containing the label name, in LABEL. */
3210 labelno = const_labelno++;
3211 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3213 /* Construct the VAR_DECL associated with the constant. */
3214 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3215 TREE_TYPE (exp));
3216 DECL_ARTIFICIAL (decl) = 1;
3217 DECL_IGNORED_P (decl) = 1;
3218 TREE_READONLY (decl) = 1;
3219 TREE_STATIC (decl) = 1;
3220 TREE_ADDRESSABLE (decl) = 1;
3221 /* We don't set the RTL yet as this would cause varpool to assume that the
3222 variable is referenced. Moreover, it would just be dropped in LTO mode.
3223 Instead we set the flag that will be recognized in make_decl_rtl. */
3224 DECL_IN_CONSTANT_POOL (decl) = 1;
3225 DECL_INITIAL (decl) = desc->value;
3226 /* ??? CONSTANT_ALIGNMENT hasn't been updated for vector types on most
3227 architectures so use DATA_ALIGNMENT as well, except for strings. */
3228 if (TREE_CODE (exp) == STRING_CST)
3230 #ifdef CONSTANT_ALIGNMENT
3231 DECL_ALIGN (decl) = CONSTANT_ALIGNMENT (exp, DECL_ALIGN (decl));
3232 #endif
3234 else
3235 align_variable (decl, 0);
3237 /* Now construct the SYMBOL_REF and the MEM. */
3238 if (use_object_blocks_p ())
3240 section *sect = get_constant_section (exp, DECL_ALIGN (decl));
3241 symbol = create_block_symbol (ggc_strdup (label),
3242 get_block_for_section (sect), -1);
3244 else
3245 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3246 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3247 SET_SYMBOL_REF_DECL (symbol, decl);
3248 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3250 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3251 set_mem_attributes (rtl, exp, 1);
3252 set_mem_alias_set (rtl, 0);
3254 /* We cannot share RTX'es in pool entries.
3255 Mark this piece of RTL as required for unsharing. */
3256 RTX_FLAG (rtl, used) = 1;
3258 /* Set flags or add text to the name to record information, such as
3259 that it is a local symbol. If the name is changed, the macro
3260 ASM_OUTPUT_LABELREF will have to know how to strip this
3261 information. This call might invalidate our local variable
3262 SYMBOL; we can't use it afterward. */
3263 targetm.encode_section_info (exp, rtl, true);
3265 desc->rtl = rtl;
3267 return desc;
3270 /* Return an rtx representing a reference to constant data in memory
3271 for the constant expression EXP.
3273 If assembler code for such a constant has already been output,
3274 return an rtx to refer to it.
3275 Otherwise, output such a constant in memory
3276 and generate an rtx for it.
3278 If DEFER is nonzero, this constant can be deferred and output only
3279 if referenced in the function after all optimizations.
3281 `const_desc_table' records which constants already have label strings. */
3284 output_constant_def (tree exp, int defer)
3286 struct constant_descriptor_tree *desc;
3287 struct constant_descriptor_tree key;
3288 void **loc;
3290 /* Look up EXP in the table of constant descriptors. If we didn't find
3291 it, create a new one. */
3292 key.value = exp;
3293 key.hash = const_hash_1 (exp);
3294 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3296 desc = (struct constant_descriptor_tree *) *loc;
3297 if (desc == 0)
3299 desc = build_constant_desc (exp);
3300 desc->hash = key.hash;
3301 *loc = desc;
3304 maybe_output_constant_def_contents (desc, defer);
3305 return desc->rtl;
3308 /* Subroutine of output_constant_def: Decide whether or not we need to
3309 output the constant DESC now, and if so, do it. */
3310 static void
3311 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3312 int defer)
3314 rtx symbol = XEXP (desc->rtl, 0);
3315 tree exp = desc->value;
3317 if (flag_syntax_only)
3318 return;
3320 if (TREE_ASM_WRITTEN (exp))
3321 /* Already output; don't do it again. */
3322 return;
3324 /* We can always defer constants as long as the context allows
3325 doing so. */
3326 if (defer)
3328 /* Increment n_deferred_constants if it exists. It needs to be at
3329 least as large as the number of constants actually referred to
3330 by the function. If it's too small we'll stop looking too early
3331 and fail to emit constants; if it's too large we'll only look
3332 through the entire function when we could have stopped earlier. */
3333 if (cfun)
3334 n_deferred_constants++;
3335 return;
3338 output_constant_def_contents (symbol);
3341 /* Subroutine of output_constant_def_contents. Output the definition
3342 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3343 constant's alignment in bits. */
3345 static void
3346 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3348 HOST_WIDE_INT size;
3350 size = get_constant_size (exp);
3352 /* Do any machine/system dependent processing of the constant. */
3353 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3355 /* Output the value of EXP. */
3356 output_constant (exp, size, align);
3359 /* We must output the constant data referred to by SYMBOL; do so. */
3361 static void
3362 output_constant_def_contents (rtx symbol)
3364 tree decl = SYMBOL_REF_DECL (symbol);
3365 tree exp = DECL_INITIAL (decl);
3366 unsigned int align;
3367 bool asan_protected = false;
3369 /* Make sure any other constants whose addresses appear in EXP
3370 are assigned label numbers. */
3371 output_addressed_constants (exp);
3373 /* We are no longer deferring this constant. */
3374 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3376 if ((flag_sanitize & SANITIZE_ADDRESS)
3377 && TREE_CODE (exp) == STRING_CST
3378 && asan_protect_global (exp))
3380 asan_protected = true;
3381 DECL_ALIGN (decl) = MAX (DECL_ALIGN (decl),
3382 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
3385 /* If the constant is part of an object block, make sure that the
3386 decl has been positioned within its block, but do not write out
3387 its definition yet. output_object_blocks will do that later. */
3388 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3389 place_block_symbol (symbol);
3390 else
3392 align = DECL_ALIGN (decl);
3393 switch_to_section (get_constant_section (exp, align));
3394 if (align > BITS_PER_UNIT)
3395 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3396 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3397 if (asan_protected)
3399 HOST_WIDE_INT size = get_constant_size (exp);
3400 assemble_zeros (asan_red_zone_size (size));
3405 /* Look up EXP in the table of constant descriptors. Return the rtl
3406 if it has been emitted, else null. */
3409 lookup_constant_def (tree exp)
3411 struct constant_descriptor_tree *desc;
3412 struct constant_descriptor_tree key;
3414 key.value = exp;
3415 key.hash = const_hash_1 (exp);
3416 desc = (struct constant_descriptor_tree *)
3417 htab_find_with_hash (const_desc_htab, &key, key.hash);
3419 return (desc ? desc->rtl : NULL_RTX);
3422 /* Return a tree representing a reference to constant data in memory
3423 for the constant expression EXP.
3425 This is the counterpart of output_constant_def at the Tree level. */
3427 tree
3428 tree_output_constant_def (tree exp)
3430 struct constant_descriptor_tree *desc, key;
3431 void **loc;
3432 tree decl;
3434 /* Look up EXP in the table of constant descriptors. If we didn't find
3435 it, create a new one. */
3436 key.value = exp;
3437 key.hash = const_hash_1 (exp);
3438 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3440 desc = (struct constant_descriptor_tree *) *loc;
3441 if (desc == 0)
3443 desc = build_constant_desc (exp);
3444 desc->hash = key.hash;
3445 *loc = desc;
3448 decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3449 varpool_finalize_decl (decl);
3450 return decl;
3453 /* Used in the hash tables to avoid outputting the same constant
3454 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3455 are output once per function, not once per file. */
3456 /* ??? Only a few targets need per-function constant pools. Most
3457 can use one per-file pool. Should add a targetm bit to tell the
3458 difference. */
3460 struct GTY(()) rtx_constant_pool {
3461 /* Pointers to first and last constant in pool, as ordered by offset. */
3462 struct constant_descriptor_rtx *first;
3463 struct constant_descriptor_rtx *last;
3465 /* Hash facility for making memory-constants from constant rtl-expressions.
3466 It is used on RISC machines where immediate integer arguments and
3467 constant addresses are restricted so that such constants must be stored
3468 in memory. */
3469 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_htab;
3471 /* Current offset in constant pool (does not include any
3472 machine-specific header). */
3473 HOST_WIDE_INT offset;
3476 struct GTY((chain_next ("%h.next"))) constant_descriptor_rtx {
3477 struct constant_descriptor_rtx *next;
3478 rtx mem;
3479 rtx sym;
3480 rtx constant;
3481 HOST_WIDE_INT offset;
3482 hashval_t hash;
3483 enum machine_mode mode;
3484 unsigned int align;
3485 int labelno;
3486 int mark;
3489 /* Hash and compare functions for const_rtx_htab. */
3491 static hashval_t
3492 const_desc_rtx_hash (const void *ptr)
3494 const struct constant_descriptor_rtx *const desc
3495 = (const struct constant_descriptor_rtx *) ptr;
3496 return desc->hash;
3499 static int
3500 const_desc_rtx_eq (const void *a, const void *b)
3502 const struct constant_descriptor_rtx *const x
3503 = (const struct constant_descriptor_rtx *) a;
3504 const struct constant_descriptor_rtx *const y
3505 = (const struct constant_descriptor_rtx *) b;
3507 if (x->mode != y->mode)
3508 return 0;
3509 return rtx_equal_p (x->constant, y->constant);
3512 /* This is the worker function for const_rtx_hash, called via for_each_rtx. */
3514 static int
3515 const_rtx_hash_1 (rtx *xp, void *data)
3517 unsigned HOST_WIDE_INT hwi;
3518 enum machine_mode mode;
3519 enum rtx_code code;
3520 hashval_t h, *hp;
3521 rtx x;
3523 x = *xp;
3524 code = GET_CODE (x);
3525 mode = GET_MODE (x);
3526 h = (hashval_t) code * 1048573 + mode;
3528 switch (code)
3530 case CONST_INT:
3531 hwi = INTVAL (x);
3532 fold_hwi:
3534 int shift = sizeof (hashval_t) * CHAR_BIT;
3535 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3536 int i;
3538 h ^= (hashval_t) hwi;
3539 for (i = 1; i < n; ++i)
3541 hwi >>= shift;
3542 h ^= (hashval_t) hwi;
3545 break;
3547 case CONST_DOUBLE:
3548 if (mode == VOIDmode)
3550 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3551 goto fold_hwi;
3553 else
3554 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3555 break;
3557 case CONST_FIXED:
3558 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3559 break;
3561 case CONST_VECTOR:
3563 int i;
3564 for (i = XVECLEN (x, 0); i-- > 0; )
3565 h = h * 251 + const_rtx_hash_1 (&XVECEXP (x, 0, i), data);
3567 break;
3569 case SYMBOL_REF:
3570 h ^= htab_hash_string (XSTR (x, 0));
3571 break;
3573 case LABEL_REF:
3574 h = h * 251 + CODE_LABEL_NUMBER (XEXP (x, 0));
3575 break;
3577 case UNSPEC:
3578 case UNSPEC_VOLATILE:
3579 h = h * 251 + XINT (x, 1);
3580 break;
3582 default:
3583 break;
3586 hp = (hashval_t *) data;
3587 *hp = *hp * 509 + h;
3588 return 0;
3591 /* Compute a hash value for X, which should be a constant. */
3593 static hashval_t
3594 const_rtx_hash (rtx x)
3596 hashval_t h = 0;
3597 for_each_rtx (&x, const_rtx_hash_1, &h);
3598 return h;
3602 /* Create and return a new rtx constant pool. */
3604 static struct rtx_constant_pool *
3605 create_constant_pool (void)
3607 struct rtx_constant_pool *pool;
3609 pool = ggc_alloc_rtx_constant_pool ();
3610 pool->const_rtx_htab = htab_create_ggc (31, const_desc_rtx_hash,
3611 const_desc_rtx_eq, NULL);
3612 pool->first = NULL;
3613 pool->last = NULL;
3614 pool->offset = 0;
3615 return pool;
3618 /* Initialize constant pool hashing for a new function. */
3620 void
3621 init_varasm_status (void)
3623 crtl->varasm.pool = create_constant_pool ();
3624 crtl->varasm.deferred_constants = 0;
3627 /* Given a MINUS expression, simplify it if both sides
3628 include the same symbol. */
3631 simplify_subtraction (rtx x)
3633 rtx r = simplify_rtx (x);
3634 return r ? r : x;
3637 /* Given a constant rtx X, make (or find) a memory constant for its value
3638 and return a MEM rtx to refer to it in memory. */
3641 force_const_mem (enum machine_mode mode, rtx x)
3643 struct constant_descriptor_rtx *desc, tmp;
3644 struct rtx_constant_pool *pool;
3645 char label[256];
3646 rtx def, symbol;
3647 hashval_t hash;
3648 unsigned int align;
3649 void **slot;
3651 /* If we're not allowed to drop X into the constant pool, don't. */
3652 if (targetm.cannot_force_const_mem (mode, x))
3653 return NULL_RTX;
3655 /* Record that this function has used a constant pool entry. */
3656 crtl->uses_const_pool = 1;
3658 /* Decide which pool to use. */
3659 pool = (targetm.use_blocks_for_constant_p (mode, x)
3660 ? shared_constant_pool
3661 : crtl->varasm.pool);
3663 /* Lookup the value in the hashtable. */
3664 tmp.constant = x;
3665 tmp.mode = mode;
3666 hash = const_rtx_hash (x);
3667 slot = htab_find_slot_with_hash (pool->const_rtx_htab, &tmp, hash, INSERT);
3668 desc = (struct constant_descriptor_rtx *) *slot;
3670 /* If the constant was already present, return its memory. */
3671 if (desc)
3672 return copy_rtx (desc->mem);
3674 /* Otherwise, create a new descriptor. */
3675 desc = ggc_alloc_constant_descriptor_rtx ();
3676 *slot = desc;
3678 /* Align the location counter as required by EXP's data type. */
3679 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3680 #ifdef CONSTANT_ALIGNMENT
3682 tree type = lang_hooks.types.type_for_mode (mode, 0);
3683 if (type != NULL_TREE)
3684 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3686 #endif
3688 pool->offset += (align / BITS_PER_UNIT) - 1;
3689 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3691 desc->next = NULL;
3692 desc->constant = copy_rtx (tmp.constant);
3693 desc->offset = pool->offset;
3694 desc->hash = hash;
3695 desc->mode = mode;
3696 desc->align = align;
3697 desc->labelno = const_labelno;
3698 desc->mark = 0;
3700 pool->offset += GET_MODE_SIZE (mode);
3701 if (pool->last)
3702 pool->last->next = desc;
3703 else
3704 pool->first = pool->last = desc;
3705 pool->last = desc;
3707 /* Create a string containing the label name, in LABEL. */
3708 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3709 ++const_labelno;
3711 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3712 the constants pool. */
3713 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3715 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3716 symbol = create_block_symbol (ggc_strdup (label),
3717 get_block_for_section (sect), -1);
3719 else
3720 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3721 desc->sym = symbol;
3722 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3723 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3724 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3726 /* Construct the MEM. */
3727 desc->mem = def = gen_const_mem (mode, symbol);
3728 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3729 set_mem_align (def, align);
3731 /* If we're dropping a label to the constant pool, make sure we
3732 don't delete it. */
3733 if (GET_CODE (x) == LABEL_REF)
3734 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3736 return copy_rtx (def);
3739 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3742 get_pool_constant (rtx addr)
3744 return SYMBOL_REF_CONSTANT (addr)->constant;
3747 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3748 and whether it has been output or not. */
3751 get_pool_constant_mark (rtx addr, bool *pmarked)
3753 struct constant_descriptor_rtx *desc;
3755 desc = SYMBOL_REF_CONSTANT (addr);
3756 *pmarked = (desc->mark != 0);
3757 return desc->constant;
3760 /* Similar, return the mode. */
3762 enum machine_mode
3763 get_pool_mode (const_rtx addr)
3765 return SYMBOL_REF_CONSTANT (addr)->mode;
3768 /* Return the size of the constant pool. */
3771 get_pool_size (void)
3773 return crtl->varasm.pool->offset;
3776 /* Worker function for output_constant_pool_1. Emit assembly for X
3777 in MODE with known alignment ALIGN. */
3779 static void
3780 output_constant_pool_2 (enum machine_mode mode, rtx x, unsigned int align)
3782 switch (GET_MODE_CLASS (mode))
3784 case MODE_FLOAT:
3785 case MODE_DECIMAL_FLOAT:
3787 REAL_VALUE_TYPE r;
3789 gcc_assert (CONST_DOUBLE_AS_FLOAT_P (x));
3790 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3791 assemble_real (r, mode, align);
3792 break;
3795 case MODE_INT:
3796 case MODE_PARTIAL_INT:
3797 case MODE_FRACT:
3798 case MODE_UFRACT:
3799 case MODE_ACCUM:
3800 case MODE_UACCUM:
3801 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3802 break;
3804 case MODE_VECTOR_FLOAT:
3805 case MODE_VECTOR_INT:
3806 case MODE_VECTOR_FRACT:
3807 case MODE_VECTOR_UFRACT:
3808 case MODE_VECTOR_ACCUM:
3809 case MODE_VECTOR_UACCUM:
3811 int i, units;
3812 enum machine_mode submode = GET_MODE_INNER (mode);
3813 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3815 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3816 units = CONST_VECTOR_NUNITS (x);
3818 for (i = 0; i < units; i++)
3820 rtx elt = CONST_VECTOR_ELT (x, i);
3821 output_constant_pool_2 (submode, elt, i ? subalign : align);
3824 break;
3826 default:
3827 gcc_unreachable ();
3831 /* Worker function for output_constant_pool. Emit constant DESC,
3832 giving it ALIGN bits of alignment. */
3834 static void
3835 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3836 unsigned int align)
3838 rtx x, tmp;
3840 x = desc->constant;
3842 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3843 whose CODE_LABEL has been deleted. This can occur if a jump table
3844 is eliminated by optimization. If so, write a constant of zero
3845 instead. Note that this can also happen by turning the
3846 CODE_LABEL into a NOTE. */
3847 /* ??? This seems completely and utterly wrong. Certainly it's
3848 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3849 functioning even with INSN_DELETED_P and friends. */
3851 tmp = x;
3852 switch (GET_CODE (tmp))
3854 case CONST:
3855 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3856 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
3857 break;
3858 tmp = XEXP (XEXP (tmp, 0), 0);
3859 /* FALLTHRU */
3861 case LABEL_REF:
3862 tmp = XEXP (tmp, 0);
3863 gcc_assert (!INSN_DELETED_P (tmp));
3864 gcc_assert (!NOTE_P (tmp)
3865 || NOTE_KIND (tmp) != NOTE_INSN_DELETED);
3866 break;
3868 default:
3869 break;
3872 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3873 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3874 align, desc->labelno, done);
3875 #endif
3877 assemble_align (align);
3879 /* Output the label. */
3880 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3882 /* Output the data. */
3883 output_constant_pool_2 (desc->mode, x, align);
3885 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3886 sections have proper size. */
3887 if (align > GET_MODE_BITSIZE (desc->mode)
3888 && in_section
3889 && (in_section->common.flags & SECTION_MERGE))
3890 assemble_align (align);
3892 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3893 done:
3894 #endif
3895 return;
3898 /* Given a SYMBOL_REF CURRENT_RTX, mark it and all constants it refers
3899 to as used. Emit referenced deferred strings. This function can
3900 be used with for_each_rtx to mark all SYMBOL_REFs in an rtx. */
3902 static int
3903 mark_constant (rtx *current_rtx, void *data ATTRIBUTE_UNUSED)
3905 rtx x = *current_rtx;
3907 if (x == NULL_RTX || GET_CODE (x) != SYMBOL_REF)
3908 return 0;
3910 if (CONSTANT_POOL_ADDRESS_P (x))
3912 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
3913 if (desc->mark == 0)
3915 desc->mark = 1;
3916 for_each_rtx (&desc->constant, mark_constant, NULL);
3919 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3921 tree decl = SYMBOL_REF_DECL (x);
3922 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
3924 n_deferred_constants--;
3925 output_constant_def_contents (x);
3929 return -1;
3932 /* Look through appropriate parts of INSN, marking all entries in the
3933 constant pool which are actually being used. Entries that are only
3934 referenced by other constants are also marked as used. Emit
3935 deferred strings that are used. */
3937 static void
3938 mark_constants (rtx insn)
3940 if (!INSN_P (insn))
3941 return;
3943 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3944 insns, not any notes that may be attached. We don't want to mark
3945 a constant just because it happens to appear in a REG_EQUIV note. */
3946 if (GET_CODE (PATTERN (insn)) == SEQUENCE)
3948 rtx seq = PATTERN (insn);
3949 int i, n = XVECLEN (seq, 0);
3950 for (i = 0; i < n; ++i)
3952 rtx subinsn = XVECEXP (seq, 0, i);
3953 if (INSN_P (subinsn))
3954 for_each_rtx (&PATTERN (subinsn), mark_constant, NULL);
3957 else
3958 for_each_rtx (&PATTERN (insn), mark_constant, NULL);
3961 /* Look through the instructions for this function, and mark all the
3962 entries in POOL which are actually being used. Emit deferred constants
3963 which have indeed been used. */
3965 static void
3966 mark_constant_pool (void)
3968 rtx insn;
3970 if (!crtl->uses_const_pool && n_deferred_constants == 0)
3971 return;
3973 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3974 mark_constants (insn);
3977 /* Write all the constants in POOL. */
3979 static void
3980 output_constant_pool_contents (struct rtx_constant_pool *pool)
3982 struct constant_descriptor_rtx *desc;
3984 for (desc = pool->first; desc ; desc = desc->next)
3985 if (desc->mark)
3987 /* If the constant is part of an object_block, make sure that
3988 the constant has been positioned within its block, but do not
3989 write out its definition yet. output_object_blocks will do
3990 that later. */
3991 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
3992 && SYMBOL_REF_BLOCK (desc->sym))
3993 place_block_symbol (desc->sym);
3994 else
3996 switch_to_section (targetm.asm_out.select_rtx_section
3997 (desc->mode, desc->constant, desc->align));
3998 output_constant_pool_1 (desc, desc->align);
4003 /* Mark all constants that are used in the current function, then write
4004 out the function's private constant pool. */
4006 static void
4007 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
4008 tree fndecl ATTRIBUTE_UNUSED)
4010 struct rtx_constant_pool *pool = crtl->varasm.pool;
4012 /* It is possible for gcc to call force_const_mem and then to later
4013 discard the instructions which refer to the constant. In such a
4014 case we do not need to output the constant. */
4015 mark_constant_pool ();
4017 #ifdef ASM_OUTPUT_POOL_PROLOGUE
4018 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
4019 #endif
4021 output_constant_pool_contents (pool);
4023 #ifdef ASM_OUTPUT_POOL_EPILOGUE
4024 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
4025 #endif
4028 /* Write the contents of the shared constant pool. */
4030 void
4031 output_shared_constant_pool (void)
4033 output_constant_pool_contents (shared_constant_pool);
4036 /* Determine what kind of relocations EXP may need. */
4039 compute_reloc_for_constant (tree exp)
4041 int reloc = 0, reloc2;
4042 tree tem;
4044 switch (TREE_CODE (exp))
4046 case ADDR_EXPR:
4047 case FDESC_EXPR:
4048 /* Go inside any operations that get_inner_reference can handle and see
4049 if what's inside is a constant: no need to do anything here for
4050 addresses of variables or functions. */
4051 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4052 tem = TREE_OPERAND (tem, 0))
4055 if (TREE_CODE (tem) == MEM_REF
4056 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
4058 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
4059 break;
4062 if (!targetm.binds_local_p (tem))
4063 reloc |= 2;
4064 else
4065 reloc |= 1;
4066 break;
4068 case PLUS_EXPR:
4069 case POINTER_PLUS_EXPR:
4070 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4071 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4072 break;
4074 case MINUS_EXPR:
4075 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4076 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
4077 /* The difference of two local labels is computable at link time. */
4078 if (reloc == 1 && reloc2 == 1)
4079 reloc = 0;
4080 else
4081 reloc |= reloc2;
4082 break;
4084 CASE_CONVERT:
4085 case VIEW_CONVERT_EXPR:
4086 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
4087 break;
4089 case CONSTRUCTOR:
4091 unsigned HOST_WIDE_INT idx;
4092 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4093 if (tem != 0)
4094 reloc |= compute_reloc_for_constant (tem);
4096 break;
4098 default:
4099 break;
4101 return reloc;
4104 /* Find all the constants whose addresses are referenced inside of EXP,
4105 and make sure assembler code with a label has been output for each one.
4106 Indicate whether an ADDR_EXPR has been encountered. */
4108 static void
4109 output_addressed_constants (tree exp)
4111 tree tem;
4113 switch (TREE_CODE (exp))
4115 case ADDR_EXPR:
4116 case FDESC_EXPR:
4117 /* Go inside any operations that get_inner_reference can handle and see
4118 if what's inside is a constant: no need to do anything here for
4119 addresses of variables or functions. */
4120 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4121 tem = TREE_OPERAND (tem, 0))
4124 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4125 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4126 tem = DECL_INITIAL (tem);
4128 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4129 output_constant_def (tem, 0);
4131 if (TREE_CODE (tem) == MEM_REF)
4132 output_addressed_constants (TREE_OPERAND (tem, 0));
4133 break;
4135 case PLUS_EXPR:
4136 case POINTER_PLUS_EXPR:
4137 case MINUS_EXPR:
4138 output_addressed_constants (TREE_OPERAND (exp, 1));
4139 /* Fall through. */
4141 CASE_CONVERT:
4142 case VIEW_CONVERT_EXPR:
4143 output_addressed_constants (TREE_OPERAND (exp, 0));
4144 break;
4146 case CONSTRUCTOR:
4148 unsigned HOST_WIDE_INT idx;
4149 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4150 if (tem != 0)
4151 output_addressed_constants (tem);
4153 break;
4155 default:
4156 break;
4160 /* Whether a constructor CTOR is a valid static constant initializer if all
4161 its elements are. This used to be internal to initializer_constant_valid_p
4162 and has been exposed to let other functions like categorize_ctor_elements
4163 evaluate the property while walking a constructor for other purposes. */
4165 bool
4166 constructor_static_from_elts_p (const_tree ctor)
4168 return (TREE_CONSTANT (ctor)
4169 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4170 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4171 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4174 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4175 tree *cache);
4177 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4178 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4179 which are valid when ENDTYPE is an integer of any size; in
4180 particular, this does not accept a pointer minus a constant. This
4181 returns null_pointer_node if the VALUE is an absolute constant
4182 which can be used to initialize a static variable. Otherwise it
4183 returns NULL. */
4185 static tree
4186 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4188 tree op0, op1;
4190 if (!INTEGRAL_TYPE_P (endtype))
4191 return NULL_TREE;
4193 op0 = TREE_OPERAND (value, 0);
4194 op1 = TREE_OPERAND (value, 1);
4196 /* Like STRIP_NOPS except allow the operand mode to widen. This
4197 works around a feature of fold that simplifies (int)(p1 - p2) to
4198 ((int)p1 - (int)p2) under the theory that the narrower operation
4199 is cheaper. */
4201 while (CONVERT_EXPR_P (op0)
4202 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4204 tree inner = TREE_OPERAND (op0, 0);
4205 if (inner == error_mark_node
4206 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4207 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
4208 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4209 break;
4210 op0 = inner;
4213 while (CONVERT_EXPR_P (op1)
4214 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4216 tree inner = TREE_OPERAND (op1, 0);
4217 if (inner == error_mark_node
4218 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4219 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
4220 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4221 break;
4222 op1 = inner;
4225 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4226 if (!op0)
4227 return NULL_TREE;
4229 op1 = initializer_constant_valid_p_1 (op1, endtype,
4230 cache ? cache + 2 : NULL);
4231 /* Both initializers must be known. */
4232 if (op1)
4234 if (op0 == op1
4235 && (op0 == null_pointer_node
4236 || TREE_CODE (value) == MINUS_EXPR))
4237 return null_pointer_node;
4239 /* Support differences between labels. */
4240 if (TREE_CODE (op0) == LABEL_DECL
4241 && TREE_CODE (op1) == LABEL_DECL)
4242 return null_pointer_node;
4244 if (TREE_CODE (op0) == STRING_CST
4245 && TREE_CODE (op1) == STRING_CST
4246 && operand_equal_p (op0, op1, 1))
4247 return null_pointer_node;
4250 return NULL_TREE;
4253 /* Helper function of initializer_constant_valid_p.
4254 Return nonzero if VALUE is a valid constant-valued expression
4255 for use in initializing a static variable; one that can be an
4256 element of a "constant" initializer.
4258 Return null_pointer_node if the value is absolute;
4259 if it is relocatable, return the variable that determines the relocation.
4260 We assume that VALUE has been folded as much as possible;
4261 therefore, we do not need to check for such things as
4262 arithmetic-combinations of integers.
4264 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4266 static tree
4267 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4269 tree ret;
4271 switch (TREE_CODE (value))
4273 case CONSTRUCTOR:
4274 if (constructor_static_from_elts_p (value))
4276 unsigned HOST_WIDE_INT idx;
4277 tree elt;
4278 bool absolute = true;
4280 if (cache && cache[0] == value)
4281 return cache[1];
4282 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4284 tree reloc;
4285 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4286 NULL);
4287 if (!reloc)
4289 if (cache)
4291 cache[0] = value;
4292 cache[1] = NULL_TREE;
4294 return NULL_TREE;
4296 if (reloc != null_pointer_node)
4297 absolute = false;
4299 /* For a non-absolute relocation, there is no single
4300 variable that can be "the variable that determines the
4301 relocation." */
4302 if (cache)
4304 cache[0] = value;
4305 cache[1] = absolute ? null_pointer_node : error_mark_node;
4307 return absolute ? null_pointer_node : error_mark_node;
4310 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4312 case INTEGER_CST:
4313 case VECTOR_CST:
4314 case REAL_CST:
4315 case FIXED_CST:
4316 case STRING_CST:
4317 case COMPLEX_CST:
4318 return null_pointer_node;
4320 case ADDR_EXPR:
4321 case FDESC_EXPR:
4323 tree op0 = staticp (TREE_OPERAND (value, 0));
4324 if (op0)
4326 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4327 to be a constant, this is old-skool offsetof-like nonsense. */
4328 if (TREE_CODE (op0) == INDIRECT_REF
4329 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4330 return null_pointer_node;
4331 /* Taking the address of a nested function involves a trampoline,
4332 unless we don't need or want one. */
4333 if (TREE_CODE (op0) == FUNCTION_DECL
4334 && DECL_STATIC_CHAIN (op0)
4335 && !TREE_NO_TRAMPOLINE (value))
4336 return NULL_TREE;
4337 /* "&{...}" requires a temporary to hold the constructed
4338 object. */
4339 if (TREE_CODE (op0) == CONSTRUCTOR)
4340 return NULL_TREE;
4342 return op0;
4345 case NON_LVALUE_EXPR:
4346 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4347 endtype, cache);
4349 case VIEW_CONVERT_EXPR:
4351 tree src = TREE_OPERAND (value, 0);
4352 tree src_type = TREE_TYPE (src);
4353 tree dest_type = TREE_TYPE (value);
4355 /* Allow view-conversions from aggregate to non-aggregate type only
4356 if the bit pattern is fully preserved afterwards; otherwise, the
4357 RTL expander won't be able to apply a subsequent transformation
4358 to the underlying constructor. */
4359 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4361 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4362 return initializer_constant_valid_p_1 (src, endtype, cache);
4363 else
4364 return NULL_TREE;
4367 /* Allow all other kinds of view-conversion. */
4368 return initializer_constant_valid_p_1 (src, endtype, cache);
4371 CASE_CONVERT:
4373 tree src = TREE_OPERAND (value, 0);
4374 tree src_type = TREE_TYPE (src);
4375 tree dest_type = TREE_TYPE (value);
4377 /* Allow conversions between pointer types, floating-point
4378 types, and offset types. */
4379 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4380 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4381 || (TREE_CODE (dest_type) == OFFSET_TYPE
4382 && TREE_CODE (src_type) == OFFSET_TYPE))
4383 return initializer_constant_valid_p_1 (src, endtype, cache);
4385 /* Allow length-preserving conversions between integer types. */
4386 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4387 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4388 return initializer_constant_valid_p_1 (src, endtype, cache);
4390 /* Allow conversions between other integer types only if
4391 explicit value. */
4392 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type))
4394 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4395 if (inner == null_pointer_node)
4396 return null_pointer_node;
4397 break;
4400 /* Allow (int) &foo provided int is as wide as a pointer. */
4401 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4402 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4403 return initializer_constant_valid_p_1 (src, endtype, cache);
4405 /* Likewise conversions from int to pointers, but also allow
4406 conversions from 0. */
4407 if ((POINTER_TYPE_P (dest_type)
4408 || TREE_CODE (dest_type) == OFFSET_TYPE)
4409 && INTEGRAL_TYPE_P (src_type))
4411 if (TREE_CODE (src) == INTEGER_CST
4412 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4413 return null_pointer_node;
4414 if (integer_zerop (src))
4415 return null_pointer_node;
4416 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4417 return initializer_constant_valid_p_1 (src, endtype, cache);
4420 /* Allow conversions to struct or union types if the value
4421 inside is okay. */
4422 if (TREE_CODE (dest_type) == RECORD_TYPE
4423 || TREE_CODE (dest_type) == UNION_TYPE)
4424 return initializer_constant_valid_p_1 (src, endtype, cache);
4426 break;
4428 case POINTER_PLUS_EXPR:
4429 case PLUS_EXPR:
4430 /* Any valid floating-point constants will have been folded by now;
4431 with -frounding-math we hit this with addition of two constants. */
4432 if (TREE_CODE (endtype) == REAL_TYPE)
4433 return NULL_TREE;
4434 if (cache && cache[0] == value)
4435 return cache[1];
4436 if (! INTEGRAL_TYPE_P (endtype)
4437 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4439 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4440 tree valid0
4441 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4442 endtype, ncache);
4443 tree valid1
4444 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4445 endtype, ncache + 2);
4446 /* If either term is absolute, use the other term's relocation. */
4447 if (valid0 == null_pointer_node)
4448 ret = valid1;
4449 else if (valid1 == null_pointer_node)
4450 ret = valid0;
4451 /* Support narrowing pointer differences. */
4452 else
4453 ret = narrowing_initializer_constant_valid_p (value, endtype,
4454 ncache);
4456 else
4457 /* Support narrowing pointer differences. */
4458 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4459 if (cache)
4461 cache[0] = value;
4462 cache[1] = ret;
4464 return ret;
4466 case MINUS_EXPR:
4467 if (TREE_CODE (endtype) == REAL_TYPE)
4468 return NULL_TREE;
4469 if (cache && cache[0] == value)
4470 return cache[1];
4471 if (! INTEGRAL_TYPE_P (endtype)
4472 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4474 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4475 tree valid0
4476 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4477 endtype, ncache);
4478 tree valid1
4479 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4480 endtype, ncache + 2);
4481 /* Win if second argument is absolute. */
4482 if (valid1 == null_pointer_node)
4483 ret = valid0;
4484 /* Win if both arguments have the same relocation.
4485 Then the value is absolute. */
4486 else if (valid0 == valid1 && valid0 != 0)
4487 ret = null_pointer_node;
4488 /* Since GCC guarantees that string constants are unique in the
4489 generated code, a subtraction between two copies of the same
4490 constant string is absolute. */
4491 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4492 && valid1 && TREE_CODE (valid1) == STRING_CST
4493 && operand_equal_p (valid0, valid1, 1))
4494 ret = null_pointer_node;
4495 /* Support narrowing differences. */
4496 else
4497 ret = narrowing_initializer_constant_valid_p (value, endtype,
4498 ncache);
4500 else
4501 /* Support narrowing differences. */
4502 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4503 if (cache)
4505 cache[0] = value;
4506 cache[1] = ret;
4508 return ret;
4510 default:
4511 break;
4514 return NULL_TREE;
4517 /* Return nonzero if VALUE is a valid constant-valued expression
4518 for use in initializing a static variable; one that can be an
4519 element of a "constant" initializer.
4521 Return null_pointer_node if the value is absolute;
4522 if it is relocatable, return the variable that determines the relocation.
4523 We assume that VALUE has been folded as much as possible;
4524 therefore, we do not need to check for such things as
4525 arithmetic-combinations of integers. */
4526 tree
4527 initializer_constant_valid_p (tree value, tree endtype)
4529 return initializer_constant_valid_p_1 (value, endtype, NULL);
4532 /* Return true if VALUE is a valid constant-valued expression
4533 for use in initializing a static bit-field; one that can be
4534 an element of a "constant" initializer. */
4536 bool
4537 initializer_constant_valid_for_bitfield_p (tree value)
4539 /* For bitfields we support integer constants or possibly nested aggregates
4540 of such. */
4541 switch (TREE_CODE (value))
4543 case CONSTRUCTOR:
4545 unsigned HOST_WIDE_INT idx;
4546 tree elt;
4548 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4549 if (!initializer_constant_valid_for_bitfield_p (elt))
4550 return false;
4551 return true;
4554 case INTEGER_CST:
4555 case REAL_CST:
4556 return true;
4558 case VIEW_CONVERT_EXPR:
4559 case NON_LVALUE_EXPR:
4560 return
4561 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4563 default:
4564 break;
4567 return false;
4570 /* output_constructor outer state of relevance in recursive calls, typically
4571 for nested aggregate bitfields. */
4573 typedef struct {
4574 unsigned int bit_offset; /* current position in ... */
4575 int byte; /* ... the outer byte buffer. */
4576 } oc_outer_state;
4578 static unsigned HOST_WIDE_INT
4579 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int,
4580 oc_outer_state *);
4582 /* Output assembler code for constant EXP, with no label.
4583 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4584 Assumes output_addressed_constants has been done on EXP already.
4586 Generate at least SIZE bytes of assembler data, padding at the end
4587 with zeros if necessary. SIZE must always be specified. The returned
4588 value is the actual number of bytes of assembler data generated, which
4589 may be bigger than SIZE if the object contains a variable length field.
4591 SIZE is important for structure constructors,
4592 since trailing members may have been omitted from the constructor.
4593 It is also important for initialization of arrays from string constants
4594 since the full length of the string constant might not be wanted.
4595 It is also needed for initialization of unions, where the initializer's
4596 type is just one member, and that may not be as long as the union.
4598 There a case in which we would fail to output exactly SIZE bytes:
4599 for a structure constructor that wants to produce more than SIZE bytes.
4600 But such constructors will never be generated for any possible input.
4602 ALIGN is the alignment of the data in bits. */
4604 static unsigned HOST_WIDE_INT
4605 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align)
4607 enum tree_code code;
4608 unsigned HOST_WIDE_INT thissize;
4610 if (size == 0 || flag_syntax_only)
4611 return size;
4613 /* See if we're trying to initialize a pointer in a non-default mode
4614 to the address of some declaration somewhere. If the target says
4615 the mode is valid for pointers, assume the target has a way of
4616 resolving it. */
4617 if (TREE_CODE (exp) == NOP_EXPR
4618 && POINTER_TYPE_P (TREE_TYPE (exp))
4619 && targetm.addr_space.valid_pointer_mode
4620 (TYPE_MODE (TREE_TYPE (exp)),
4621 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4623 tree saved_type = TREE_TYPE (exp);
4625 /* Peel off any intermediate conversions-to-pointer for valid
4626 pointer modes. */
4627 while (TREE_CODE (exp) == NOP_EXPR
4628 && POINTER_TYPE_P (TREE_TYPE (exp))
4629 && targetm.addr_space.valid_pointer_mode
4630 (TYPE_MODE (TREE_TYPE (exp)),
4631 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4632 exp = TREE_OPERAND (exp, 0);
4634 /* If what we're left with is the address of something, we can
4635 convert the address to the final type and output it that
4636 way. */
4637 if (TREE_CODE (exp) == ADDR_EXPR)
4638 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4639 /* Likewise for constant ints. */
4640 else if (TREE_CODE (exp) == INTEGER_CST)
4641 exp = build_int_cst_wide (saved_type, TREE_INT_CST_LOW (exp),
4642 TREE_INT_CST_HIGH (exp));
4646 /* Eliminate any conversions since we'll be outputting the underlying
4647 constant. */
4648 while (CONVERT_EXPR_P (exp)
4649 || TREE_CODE (exp) == NON_LVALUE_EXPR
4650 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4652 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4653 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4655 /* Make sure eliminating the conversion is really a no-op, except with
4656 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4657 union types to allow for Ada unchecked unions. */
4658 if (type_size > op_size
4659 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4660 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4661 /* Keep the conversion. */
4662 break;
4663 else
4664 exp = TREE_OPERAND (exp, 0);
4667 code = TREE_CODE (TREE_TYPE (exp));
4668 thissize = int_size_in_bytes (TREE_TYPE (exp));
4670 /* Allow a constructor with no elements for any data type.
4671 This means to fill the space with zeros. */
4672 if (TREE_CODE (exp) == CONSTRUCTOR
4673 && vec_safe_is_empty (CONSTRUCTOR_ELTS (exp)))
4675 assemble_zeros (size);
4676 return size;
4679 if (TREE_CODE (exp) == FDESC_EXPR)
4681 #ifdef ASM_OUTPUT_FDESC
4682 HOST_WIDE_INT part = tree_to_shwi (TREE_OPERAND (exp, 1));
4683 tree decl = TREE_OPERAND (exp, 0);
4684 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4685 #else
4686 gcc_unreachable ();
4687 #endif
4688 return size;
4691 /* Now output the underlying data. If we've handling the padding, return.
4692 Otherwise, break and ensure SIZE is the size written. */
4693 switch (code)
4695 case BOOLEAN_TYPE:
4696 case INTEGER_TYPE:
4697 case ENUMERAL_TYPE:
4698 case POINTER_TYPE:
4699 case REFERENCE_TYPE:
4700 case OFFSET_TYPE:
4701 case FIXED_POINT_TYPE:
4702 case NULLPTR_TYPE:
4703 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
4704 EXPAND_INITIALIZER),
4705 MIN (size, thissize), align, 0))
4706 error ("initializer for integer/fixed-point value is too complicated");
4707 break;
4709 case REAL_TYPE:
4710 if (TREE_CODE (exp) != REAL_CST)
4711 error ("initializer for floating value is not a floating constant");
4712 else
4713 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)), align);
4714 break;
4716 case COMPLEX_TYPE:
4717 output_constant (TREE_REALPART (exp), thissize / 2, align);
4718 output_constant (TREE_IMAGPART (exp), thissize / 2,
4719 min_align (align, BITS_PER_UNIT * (thissize / 2)));
4720 break;
4722 case ARRAY_TYPE:
4723 case VECTOR_TYPE:
4724 switch (TREE_CODE (exp))
4726 case CONSTRUCTOR:
4727 return output_constructor (exp, size, align, NULL);
4728 case STRING_CST:
4729 thissize
4730 = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp), size);
4731 assemble_string (TREE_STRING_POINTER (exp), thissize);
4732 break;
4733 case VECTOR_CST:
4735 enum machine_mode inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4736 unsigned int nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4737 int elt_size = GET_MODE_SIZE (inner);
4738 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align);
4739 thissize = elt_size;
4740 for (unsigned int i = 1; i < VECTOR_CST_NELTS (exp); i++)
4742 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign);
4743 thissize += elt_size;
4745 break;
4747 default:
4748 gcc_unreachable ();
4750 break;
4752 case RECORD_TYPE:
4753 case UNION_TYPE:
4754 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4755 return output_constructor (exp, size, align, NULL);
4757 case ERROR_MARK:
4758 return 0;
4760 default:
4761 gcc_unreachable ();
4764 if (size > thissize)
4765 assemble_zeros (size - thissize);
4767 return size;
4771 /* Subroutine of output_constructor, used for computing the size of
4772 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4773 type with an unspecified upper bound. */
4775 static unsigned HOST_WIDE_INT
4776 array_size_for_constructor (tree val)
4778 tree max_index;
4779 unsigned HOST_WIDE_INT cnt;
4780 tree index, value, tmp;
4781 double_int i;
4783 /* This code used to attempt to handle string constants that are not
4784 arrays of single-bytes, but nothing else does, so there's no point in
4785 doing it here. */
4786 if (TREE_CODE (val) == STRING_CST)
4787 return TREE_STRING_LENGTH (val);
4789 max_index = NULL_TREE;
4790 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
4792 if (TREE_CODE (index) == RANGE_EXPR)
4793 index = TREE_OPERAND (index, 1);
4794 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
4795 max_index = index;
4798 if (max_index == NULL_TREE)
4799 return 0;
4801 /* Compute the total number of array elements. */
4802 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
4803 i = tree_to_double_int (max_index) - tree_to_double_int (tmp);
4804 i += double_int_one;
4806 /* Multiply by the array element unit size to find number of bytes. */
4807 i *= tree_to_double_int (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
4809 gcc_assert (i.fits_uhwi ());
4810 return i.low;
4813 /* Other datastructures + helpers for output_constructor. */
4815 /* output_constructor local state to support interaction with helpers. */
4817 typedef struct {
4819 /* Received arguments. */
4820 tree exp; /* Constructor expression. */
4821 tree type; /* Type of constructor expression. */
4822 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */
4823 unsigned int align; /* Known initial alignment. */
4824 tree min_index; /* Lower bound if specified for an array. */
4826 /* Output processing state. */
4827 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */
4828 int byte; /* Part of a bitfield byte yet to be output. */
4829 int last_relative_index; /* Implicit or explicit index of the last
4830 array element output within a bitfield. */
4831 bool byte_buffer_in_use; /* Whether BYTE is in use. */
4833 /* Current element. */
4834 tree field; /* Current field decl in a record. */
4835 tree val; /* Current element value. */
4836 tree index; /* Current element index. */
4838 } oc_local_state;
4840 /* Helper for output_constructor. From the current LOCAL state, output a
4841 RANGE_EXPR element. */
4843 static void
4844 output_constructor_array_range (oc_local_state *local)
4846 unsigned HOST_WIDE_INT fieldsize
4847 = int_size_in_bytes (TREE_TYPE (local->type));
4849 HOST_WIDE_INT lo_index
4850 = tree_to_shwi (TREE_OPERAND (local->index, 0));
4851 HOST_WIDE_INT hi_index
4852 = tree_to_shwi (TREE_OPERAND (local->index, 1));
4853 HOST_WIDE_INT index;
4855 unsigned int align2
4856 = min_align (local->align, fieldsize * BITS_PER_UNIT);
4858 for (index = lo_index; index <= hi_index; index++)
4860 /* Output the element's initial value. */
4861 if (local->val == NULL_TREE)
4862 assemble_zeros (fieldsize);
4863 else
4864 fieldsize = output_constant (local->val, fieldsize, align2);
4866 /* Count its size. */
4867 local->total_bytes += fieldsize;
4871 /* Helper for output_constructor. From the current LOCAL state, output a
4872 field element that is not true bitfield or part of an outer one. */
4874 static void
4875 output_constructor_regular_field (oc_local_state *local)
4877 /* Field size and position. Since this structure is static, we know the
4878 positions are constant. */
4879 unsigned HOST_WIDE_INT fieldsize;
4880 HOST_WIDE_INT fieldpos;
4882 unsigned int align2;
4884 if (local->index != NULL_TREE)
4886 /* Perform the index calculation in modulo arithmetic but
4887 sign-extend the result because Ada has negative DECL_FIELD_OFFSETs
4888 but we are using an unsigned sizetype. */
4889 unsigned prec = TYPE_PRECISION (sizetype);
4890 double_int idx = tree_to_double_int (local->index)
4891 - tree_to_double_int (local->min_index);
4892 idx = idx.sext (prec);
4893 fieldpos = (tree_to_uhwi (TYPE_SIZE_UNIT (TREE_TYPE (local->val)))
4894 * idx.low);
4896 else if (local->field != NULL_TREE)
4897 fieldpos = int_byte_position (local->field);
4898 else
4899 fieldpos = 0;
4901 /* Output any buffered-up bit-fields preceding this element. */
4902 if (local->byte_buffer_in_use)
4904 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4905 local->total_bytes++;
4906 local->byte_buffer_in_use = false;
4909 /* Advance to offset of this element.
4910 Note no alignment needed in an array, since that is guaranteed
4911 if each element has the proper size. */
4912 if ((local->field != NULL_TREE || local->index != NULL_TREE)
4913 && fieldpos > local->total_bytes)
4915 assemble_zeros (fieldpos - local->total_bytes);
4916 local->total_bytes = fieldpos;
4919 /* Find the alignment of this element. */
4920 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
4922 /* Determine size this element should occupy. */
4923 if (local->field)
4925 fieldsize = 0;
4927 /* If this is an array with an unspecified upper bound,
4928 the initializer determines the size. */
4929 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
4930 but we cannot do this until the deprecated support for
4931 initializing zero-length array members is removed. */
4932 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
4933 && TYPE_DOMAIN (TREE_TYPE (local->field))
4934 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field))))
4936 fieldsize = array_size_for_constructor (local->val);
4937 /* Given a non-empty initialization, this field had
4938 better be last. */
4939 gcc_assert (!fieldsize || !DECL_CHAIN (local->field));
4941 else
4942 fieldsize = tree_to_uhwi (DECL_SIZE_UNIT (local->field));
4944 else
4945 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
4947 /* Output the element's initial value. */
4948 if (local->val == NULL_TREE)
4949 assemble_zeros (fieldsize);
4950 else
4951 fieldsize = output_constant (local->val, fieldsize, align2);
4953 /* Count its size. */
4954 local->total_bytes += fieldsize;
4957 /* Helper for output_constructor. From the LOCAL state, output an element
4958 that is a true bitfield or part of an outer one. BIT_OFFSET is the offset
4959 from the start of a possibly ongoing outer byte buffer. */
4961 static void
4962 output_constructor_bitfield (oc_local_state *local, unsigned int bit_offset)
4964 /* Bit size of this element. */
4965 HOST_WIDE_INT ebitsize
4966 = (local->field
4967 ? tree_to_uhwi (DECL_SIZE (local->field))
4968 : tree_to_uhwi (TYPE_SIZE (TREE_TYPE (local->type))));
4970 /* Relative index of this element if this is an array component. */
4971 HOST_WIDE_INT relative_index
4972 = (!local->field
4973 ? (local->index
4974 ? (tree_to_shwi (local->index)
4975 - tree_to_shwi (local->min_index))
4976 : local->last_relative_index + 1)
4977 : 0);
4979 /* Bit position of this element from the start of the containing
4980 constructor. */
4981 HOST_WIDE_INT constructor_relative_ebitpos
4982 = (local->field
4983 ? int_bit_position (local->field)
4984 : ebitsize * relative_index);
4986 /* Bit position of this element from the start of a possibly ongoing
4987 outer byte buffer. */
4988 HOST_WIDE_INT byte_relative_ebitpos
4989 = bit_offset + constructor_relative_ebitpos;
4991 /* From the start of a possibly ongoing outer byte buffer, offsets to
4992 the first bit of this element and to the first bit past the end of
4993 this element. */
4994 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
4995 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
4997 local->last_relative_index = relative_index;
4999 if (local->val == NULL_TREE)
5000 local->val = integer_zero_node;
5002 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
5003 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
5004 local->val = TREE_OPERAND (local->val, 0);
5006 if (TREE_CODE (local->val) != INTEGER_CST
5007 && TREE_CODE (local->val) != CONSTRUCTOR)
5009 error ("invalid initial value for member %qE", DECL_NAME (local->field));
5010 return;
5013 /* If this field does not start in this (or next) byte, skip some bytes. */
5014 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5016 /* Output remnant of any bit field in previous bytes. */
5017 if (local->byte_buffer_in_use)
5019 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5020 local->total_bytes++;
5021 local->byte_buffer_in_use = false;
5024 /* If still not at proper byte, advance to there. */
5025 if (next_offset / BITS_PER_UNIT != local->total_bytes)
5027 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
5028 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
5029 local->total_bytes = next_offset / BITS_PER_UNIT;
5033 /* Set up the buffer if necessary. */
5034 if (!local->byte_buffer_in_use)
5036 local->byte = 0;
5037 if (ebitsize > 0)
5038 local->byte_buffer_in_use = true;
5041 /* If this is nested constructor, recurse passing the bit offset and the
5042 pending data, then retrieve the new pending data afterwards. */
5043 if (TREE_CODE (local->val) == CONSTRUCTOR)
5045 oc_outer_state temp_state;
5046 temp_state.bit_offset = next_offset % BITS_PER_UNIT;
5047 temp_state.byte = local->byte;
5048 local->total_bytes
5049 += output_constructor (local->val, 0, 0, &temp_state);
5050 local->byte = temp_state.byte;
5051 return;
5054 /* Otherwise, we must split the element into pieces that fall within
5055 separate bytes, and combine each byte with previous or following
5056 bit-fields. */
5057 while (next_offset < end_offset)
5059 int this_time;
5060 int shift;
5061 HOST_WIDE_INT value;
5062 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
5063 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
5065 /* Advance from byte to byte within this element when necessary. */
5066 while (next_byte != local->total_bytes)
5068 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
5069 local->total_bytes++;
5070 local->byte = 0;
5073 /* Number of bits we can process at once (all part of the same byte). */
5074 this_time = MIN (end_offset - next_offset, BITS_PER_UNIT - next_bit);
5075 if (BYTES_BIG_ENDIAN)
5077 /* On big-endian machine, take the most significant bits
5078 first (of the bits that are significant)
5079 and put them into bytes from the most significant end. */
5080 shift = end_offset - next_offset - this_time;
5082 /* Don't try to take a bunch of bits that cross
5083 the word boundary in the INTEGER_CST. We can
5084 only select bits from the LOW or HIGH part
5085 not from both. */
5086 if (shift < HOST_BITS_PER_WIDE_INT
5087 && shift + this_time > HOST_BITS_PER_WIDE_INT)
5089 this_time = shift + this_time - HOST_BITS_PER_WIDE_INT;
5090 shift = HOST_BITS_PER_WIDE_INT;
5093 /* Now get the bits from the appropriate constant word. */
5094 if (shift < HOST_BITS_PER_WIDE_INT)
5095 value = TREE_INT_CST_LOW (local->val);
5096 else
5098 gcc_assert (shift < HOST_BITS_PER_DOUBLE_INT);
5099 value = TREE_INT_CST_HIGH (local->val);
5100 shift -= HOST_BITS_PER_WIDE_INT;
5103 /* Get the result. This works only when:
5104 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5105 local->byte |= (((value >> shift)
5106 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5107 << (BITS_PER_UNIT - this_time - next_bit));
5109 else
5111 /* On little-endian machines,
5112 take first the least significant bits of the value
5113 and pack them starting at the least significant
5114 bits of the bytes. */
5115 shift = next_offset - byte_relative_ebitpos;
5117 /* Don't try to take a bunch of bits that cross
5118 the word boundary in the INTEGER_CST. We can
5119 only select bits from the LOW or HIGH part
5120 not from both. */
5121 if (shift < HOST_BITS_PER_WIDE_INT
5122 && shift + this_time > HOST_BITS_PER_WIDE_INT)
5123 this_time = (HOST_BITS_PER_WIDE_INT - shift);
5125 /* Now get the bits from the appropriate constant word. */
5126 if (shift < HOST_BITS_PER_WIDE_INT)
5127 value = TREE_INT_CST_LOW (local->val);
5128 else
5130 gcc_assert (shift < HOST_BITS_PER_DOUBLE_INT);
5131 value = TREE_INT_CST_HIGH (local->val);
5132 shift -= HOST_BITS_PER_WIDE_INT;
5135 /* Get the result. This works only when:
5136 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5137 local->byte |= (((value >> shift)
5138 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5139 << next_bit);
5142 next_offset += this_time;
5143 local->byte_buffer_in_use = true;
5147 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5148 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5149 caller output state of relevance in recursive invocations. */
5151 static unsigned HOST_WIDE_INT
5152 output_constructor (tree exp, unsigned HOST_WIDE_INT size,
5153 unsigned int align, oc_outer_state *outer)
5155 unsigned HOST_WIDE_INT cnt;
5156 constructor_elt *ce;
5158 oc_local_state local;
5160 /* Setup our local state to communicate with helpers. */
5161 local.exp = exp;
5162 local.type = TREE_TYPE (exp);
5163 local.size = size;
5164 local.align = align;
5165 if (TREE_CODE (local.type) == ARRAY_TYPE && TYPE_DOMAIN (local.type))
5166 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5167 else
5168 local.min_index = NULL_TREE;
5170 local.total_bytes = 0;
5171 local.byte_buffer_in_use = outer != NULL;
5172 local.byte = outer ? outer->byte : 0;
5173 local.last_relative_index = -1;
5175 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5177 /* As CE goes through the elements of the constant, FIELD goes through the
5178 structure fields if the constant is a structure. If the constant is a
5179 union, we override this by getting the field from the TREE_LIST element.
5180 But the constant could also be an array. Then FIELD is zero.
5182 There is always a maximum of one element in the chain LINK for unions
5183 (even if the initializer in a source program incorrectly contains
5184 more one). */
5186 if (TREE_CODE (local.type) == RECORD_TYPE)
5187 local.field = TYPE_FIELDS (local.type);
5188 else
5189 local.field = NULL_TREE;
5191 for (cnt = 0;
5192 vec_safe_iterate (CONSTRUCTOR_ELTS (exp), cnt, &ce);
5193 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5195 local.val = ce->value;
5196 local.index = NULL_TREE;
5198 /* The element in a union constructor specifies the proper field
5199 or index. */
5200 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5201 local.field = ce->index;
5203 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5204 local.index = ce->index;
5206 if (local.field && flag_verbose_asm)
5207 fprintf (asm_out_file, "%s %s:\n",
5208 ASM_COMMENT_START,
5209 DECL_NAME (local.field)
5210 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5211 : "<anonymous>");
5213 /* Eliminate the marker that makes a cast not be an lvalue. */
5214 if (local.val != NULL_TREE)
5215 STRIP_NOPS (local.val);
5217 /* Output the current element, using the appropriate helper ... */
5219 /* For an array slice not part of an outer bitfield. */
5220 if (!outer
5221 && local.index != NULL_TREE
5222 && TREE_CODE (local.index) == RANGE_EXPR)
5223 output_constructor_array_range (&local);
5225 /* For a field that is neither a true bitfield nor part of an outer one,
5226 known to be at least byte aligned and multiple-of-bytes long. */
5227 else if (!outer
5228 && (local.field == NULL_TREE
5229 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5230 output_constructor_regular_field (&local);
5232 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5233 supported for scalar fields, so we may need to convert first. */
5234 else
5236 if (TREE_CODE (local.val) == REAL_CST)
5237 local.val
5238 = fold_unary (VIEW_CONVERT_EXPR,
5239 build_nonstandard_integer_type
5240 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5241 local.val);
5242 output_constructor_bitfield (&local, outer ? outer->bit_offset : 0);
5246 /* If we are not at toplevel, save the pending data for our caller.
5247 Otherwise output the pending data and padding zeros as needed. */
5248 if (outer)
5249 outer->byte = local.byte;
5250 else
5252 if (local.byte_buffer_in_use)
5254 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5255 local.total_bytes++;
5258 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5260 assemble_zeros (local.size - local.total_bytes);
5261 local.total_bytes = local.size;
5265 return local.total_bytes;
5268 /* Mark DECL as weak. */
5270 static void
5271 mark_weak (tree decl)
5273 DECL_WEAK (decl) = 1;
5275 if (DECL_RTL_SET_P (decl)
5276 && MEM_P (DECL_RTL (decl))
5277 && XEXP (DECL_RTL (decl), 0)
5278 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5279 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5282 /* Merge weak status between NEWDECL and OLDDECL. */
5284 void
5285 merge_weak (tree newdecl, tree olddecl)
5287 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5289 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5291 tree *pwd;
5292 /* We put the NEWDECL on the weak_decls list at some point
5293 and OLDDECL as well. Keep just OLDDECL on the list. */
5294 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5295 if (TREE_VALUE (*pwd) == newdecl)
5297 *pwd = TREE_CHAIN (*pwd);
5298 break;
5301 return;
5304 if (DECL_WEAK (newdecl))
5306 tree wd;
5308 /* NEWDECL is weak, but OLDDECL is not. */
5310 /* If we already output the OLDDECL, we're in trouble; we can't
5311 go back and make it weak. This should never happen in
5312 unit-at-a-time compilation. */
5313 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5315 /* If we've already generated rtl referencing OLDDECL, we may
5316 have done so in a way that will not function properly with
5317 a weak symbol. Again in unit-at-a-time this should be
5318 impossible. */
5319 gcc_assert (!TREE_USED (olddecl)
5320 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5322 if (TARGET_SUPPORTS_WEAK)
5324 /* We put the NEWDECL on the weak_decls list at some point.
5325 Replace it with the OLDDECL. */
5326 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5327 if (TREE_VALUE (wd) == newdecl)
5329 TREE_VALUE (wd) = olddecl;
5330 break;
5332 /* We may not find the entry on the list. If NEWDECL is a
5333 weak alias, then we will have already called
5334 globalize_decl to remove the entry; in that case, we do
5335 not need to do anything. */
5338 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5339 mark_weak (olddecl);
5341 else
5342 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5343 weak. Just update NEWDECL to indicate that it's weak too. */
5344 mark_weak (newdecl);
5347 /* Declare DECL to be a weak symbol. */
5349 void
5350 declare_weak (tree decl)
5352 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5353 if (! TREE_PUBLIC (decl))
5354 error ("weak declaration of %q+D must be public", decl);
5355 else if (!TARGET_SUPPORTS_WEAK)
5356 warning (0, "weak declaration of %q+D not supported", decl);
5358 mark_weak (decl);
5359 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5360 DECL_ATTRIBUTES (decl)
5361 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5364 static void
5365 weak_finish_1 (tree decl)
5367 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5368 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5369 #endif
5371 if (! TREE_USED (decl))
5372 return;
5374 #ifdef ASM_WEAKEN_DECL
5375 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5376 #else
5377 #ifdef ASM_WEAKEN_LABEL
5378 ASM_WEAKEN_LABEL (asm_out_file, name);
5379 #else
5380 #ifdef ASM_OUTPUT_WEAK_ALIAS
5382 static bool warn_once = 0;
5383 if (! warn_once)
5385 warning (0, "only weak aliases are supported in this configuration");
5386 warn_once = 1;
5388 return;
5390 #endif
5391 #endif
5392 #endif
5395 /* Fiven an assembly name, find the decl it is associated with. */
5396 static tree
5397 find_decl (tree target)
5399 symtab_node *node = symtab_node_for_asm (target);
5400 if (node)
5401 return node->decl;
5402 return NULL_TREE;
5405 /* This TREE_LIST contains weakref targets. */
5407 static GTY(()) tree weakref_targets;
5409 /* Emit any pending weak declarations. */
5411 void
5412 weak_finish (void)
5414 tree t;
5416 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5418 tree alias_decl = TREE_PURPOSE (t);
5419 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5421 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5422 /* Remove alias_decl from the weak list, but leave entries for
5423 the target alone. */
5424 target = NULL_TREE;
5425 #ifndef ASM_OUTPUT_WEAKREF
5426 else if (! TREE_SYMBOL_REFERENCED (target))
5428 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5429 defined, otherwise we and weak_finish_1 would use
5430 different macros. */
5431 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5432 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5433 # else
5434 tree decl = find_decl (target);
5436 if (! decl)
5438 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5439 TREE_CODE (alias_decl), target,
5440 TREE_TYPE (alias_decl));
5442 DECL_EXTERNAL (decl) = 1;
5443 TREE_PUBLIC (decl) = 1;
5444 DECL_ARTIFICIAL (decl) = 1;
5445 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5446 TREE_USED (decl) = 1;
5449 weak_finish_1 (decl);
5450 # endif
5452 #endif
5455 tree *p;
5456 tree t2;
5458 /* Remove the alias and the target from the pending weak list
5459 so that we do not emit any .weak directives for the former,
5460 nor multiple .weak directives for the latter. */
5461 for (p = &weak_decls; (t2 = *p) ; )
5463 if (TREE_VALUE (t2) == alias_decl
5464 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5465 *p = TREE_CHAIN (t2);
5466 else
5467 p = &TREE_CHAIN (t2);
5470 /* Remove other weakrefs to the same target, to speed things up. */
5471 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5473 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5474 *p = TREE_CHAIN (t2);
5475 else
5476 p = &TREE_CHAIN (t2);
5481 for (t = weak_decls; t; t = TREE_CHAIN (t))
5483 tree decl = TREE_VALUE (t);
5485 weak_finish_1 (decl);
5489 /* Emit the assembly bits to indicate that DECL is globally visible. */
5491 static void
5492 globalize_decl (tree decl)
5495 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5496 if (DECL_WEAK (decl))
5498 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5499 tree *p, t;
5501 #ifdef ASM_WEAKEN_DECL
5502 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5503 #else
5504 ASM_WEAKEN_LABEL (asm_out_file, name);
5505 #endif
5507 /* Remove this function from the pending weak list so that
5508 we do not emit multiple .weak directives for it. */
5509 for (p = &weak_decls; (t = *p) ; )
5511 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5512 *p = TREE_CHAIN (t);
5513 else
5514 p = &TREE_CHAIN (t);
5517 /* Remove weakrefs to the same target from the pending weakref
5518 list, for the same reason. */
5519 for (p = &weakref_targets; (t = *p) ; )
5521 if (DECL_ASSEMBLER_NAME (decl)
5522 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5523 *p = TREE_CHAIN (t);
5524 else
5525 p = &TREE_CHAIN (t);
5528 return;
5530 #endif
5532 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5535 vec<alias_pair, va_gc> *alias_pairs;
5537 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5538 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5539 tree node is DECL to have the value of the tree node TARGET. */
5541 void
5542 do_assemble_alias (tree decl, tree target)
5544 /* Emulated TLS had better not get this var. */
5545 gcc_assert (!(!targetm.have_tls
5546 && TREE_CODE (decl) == VAR_DECL
5547 && DECL_THREAD_LOCAL_P (decl)));
5549 if (TREE_ASM_WRITTEN (decl))
5550 return;
5552 /* We must force creation of DECL_RTL for debug info generation, even though
5553 we don't use it here. */
5554 make_decl_rtl (decl);
5556 TREE_ASM_WRITTEN (decl) = 1;
5557 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5559 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5561 ultimate_transparent_alias_target (&target);
5563 if (!TREE_SYMBOL_REFERENCED (target))
5564 weakref_targets = tree_cons (decl, target, weakref_targets);
5566 #ifdef ASM_OUTPUT_WEAKREF
5567 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5568 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5569 IDENTIFIER_POINTER (target));
5570 #else
5571 if (!TARGET_SUPPORTS_WEAK)
5573 error_at (DECL_SOURCE_LOCATION (decl),
5574 "weakref is not supported in this configuration");
5575 return;
5577 #endif
5578 return;
5581 #ifdef ASM_OUTPUT_DEF
5582 /* Make name accessible from other files, if appropriate. */
5584 if (TREE_PUBLIC (decl))
5586 globalize_decl (decl);
5587 maybe_assemble_visibility (decl);
5589 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5591 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE)
5592 if (targetm.has_ifunc_p ())
5593 ASM_OUTPUT_TYPE_DIRECTIVE
5594 (asm_out_file, IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5595 IFUNC_ASM_TYPE);
5596 else
5597 #endif
5598 error_at (DECL_SOURCE_LOCATION (decl),
5599 "ifunc is not supported on this target");
5602 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5603 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5604 # else
5605 ASM_OUTPUT_DEF (asm_out_file,
5606 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5607 IDENTIFIER_POINTER (target));
5608 # endif
5609 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5611 const char *name;
5612 tree *p, t;
5614 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5615 # ifdef ASM_WEAKEN_DECL
5616 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5617 # else
5618 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5619 # endif
5620 /* Remove this function from the pending weak list so that
5621 we do not emit multiple .weak directives for it. */
5622 for (p = &weak_decls; (t = *p) ; )
5623 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5624 *p = TREE_CHAIN (t);
5625 else
5626 p = &TREE_CHAIN (t);
5628 /* Remove weakrefs to the same target from the pending weakref
5629 list, for the same reason. */
5630 for (p = &weakref_targets; (t = *p) ; )
5632 if (DECL_ASSEMBLER_NAME (decl)
5633 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5634 *p = TREE_CHAIN (t);
5635 else
5636 p = &TREE_CHAIN (t);
5639 #endif
5642 /* Emit an assembler directive to make the symbol for DECL an alias to
5643 the symbol for TARGET. */
5645 void
5646 assemble_alias (tree decl, tree target)
5648 tree target_decl;
5650 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5652 tree alias = DECL_ASSEMBLER_NAME (decl);
5654 ultimate_transparent_alias_target (&target);
5656 if (alias == target)
5657 error ("weakref %q+D ultimately targets itself", decl);
5658 if (TREE_PUBLIC (decl))
5659 error ("weakref %q+D must have static linkage", decl);
5661 else
5663 #if !defined (ASM_OUTPUT_DEF)
5664 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5665 error_at (DECL_SOURCE_LOCATION (decl),
5666 "alias definitions not supported in this configuration");
5667 TREE_ASM_WRITTEN (decl) = 1;
5668 return;
5669 # else
5670 if (!DECL_WEAK (decl))
5672 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5673 error_at (DECL_SOURCE_LOCATION (decl),
5674 "ifunc is not supported in this configuration");
5675 else
5676 error_at (DECL_SOURCE_LOCATION (decl),
5677 "only weak aliases are supported in this configuration");
5678 TREE_ASM_WRITTEN (decl) = 1;
5679 return;
5681 # endif
5682 #endif
5684 TREE_USED (decl) = 1;
5686 /* Allow aliases to aliases. */
5687 if (TREE_CODE (decl) == FUNCTION_DECL)
5688 cgraph_get_create_node (decl)->alias = true;
5689 else
5690 varpool_node_for_decl (decl)->alias = true;
5692 /* If the target has already been emitted, we don't have to queue the
5693 alias. This saves a tad of memory. */
5694 if (cgraph_global_info_ready)
5695 target_decl = find_decl (target);
5696 else
5697 target_decl= NULL;
5698 if ((target_decl && TREE_ASM_WRITTEN (target_decl))
5699 || cgraph_state >= CGRAPH_STATE_EXPANSION)
5700 do_assemble_alias (decl, target);
5701 else
5703 alias_pair p = {decl, target};
5704 vec_safe_push (alias_pairs, p);
5708 /* Record and output a table of translations from original function
5709 to its transaction aware clone. Note that tm_pure functions are
5710 considered to be their own clone. */
5712 static GTY((if_marked ("tree_map_marked_p"), param_is (struct tree_map)))
5713 htab_t tm_clone_hash;
5715 void
5716 record_tm_clone_pair (tree o, tree n)
5718 struct tree_map **slot, *h;
5720 if (tm_clone_hash == NULL)
5721 tm_clone_hash = htab_create_ggc (32, tree_map_hash, tree_map_eq, 0);
5723 h = ggc_alloc_tree_map ();
5724 h->hash = htab_hash_pointer (o);
5725 h->base.from = o;
5726 h->to = n;
5728 slot = (struct tree_map **)
5729 htab_find_slot_with_hash (tm_clone_hash, h, h->hash, INSERT);
5730 *slot = h;
5733 tree
5734 get_tm_clone_pair (tree o)
5736 if (tm_clone_hash)
5738 struct tree_map *h, in;
5740 in.base.from = o;
5741 in.hash = htab_hash_pointer (o);
5742 h = (struct tree_map *) htab_find_with_hash (tm_clone_hash,
5743 &in, in.hash);
5744 if (h)
5745 return h->to;
5747 return NULL_TREE;
5750 typedef struct tm_alias_pair
5752 unsigned int uid;
5753 tree from;
5754 tree to;
5755 } tm_alias_pair;
5758 /* Helper function for finish_tm_clone_pairs. Dump a hash table entry
5759 into a VEC in INFO. */
5761 static int
5762 dump_tm_clone_to_vec (void **slot, void *info)
5764 struct tree_map *map = (struct tree_map *) *slot;
5765 vec<tm_alias_pair> *tm_alias_pairs = (vec<tm_alias_pair> *) info;
5766 tm_alias_pair p = {DECL_UID (map->base.from), map->base.from, map->to};
5767 tm_alias_pairs->safe_push (p);
5768 return 1;
5771 /* Dump the actual pairs to the .tm_clone_table section. */
5773 static void
5774 dump_tm_clone_pairs (vec<tm_alias_pair> tm_alias_pairs)
5776 unsigned i;
5777 tm_alias_pair *p;
5778 bool switched = false;
5780 FOR_EACH_VEC_ELT (tm_alias_pairs, i, p)
5782 tree src = p->from;
5783 tree dst = p->to;
5784 struct cgraph_node *src_n = cgraph_get_node (src);
5785 struct cgraph_node *dst_n = cgraph_get_node (dst);
5787 /* The function ipa_tm_create_version() marks the clone as needed if
5788 the original function was needed. But we also mark the clone as
5789 needed if we ever called the clone indirectly through
5790 TM_GETTMCLONE. If neither of these are true, we didn't generate
5791 a clone, and we didn't call it indirectly... no sense keeping it
5792 in the clone table. */
5793 if (!dst_n || !dst_n->definition)
5794 continue;
5796 /* This covers the case where we have optimized the original
5797 function away, and only access the transactional clone. */
5798 if (!src_n || !src_n->definition)
5799 continue;
5801 if (!switched)
5803 switch_to_section (targetm.asm_out.tm_clone_table_section ());
5804 assemble_align (POINTER_SIZE);
5805 switched = true;
5808 assemble_integer (XEXP (DECL_RTL (src), 0),
5809 POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
5810 assemble_integer (XEXP (DECL_RTL (dst), 0),
5811 POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
5815 /* Provide a default for the tm_clone_table section. */
5817 section *
5818 default_clone_table_section (void)
5820 return get_named_section (NULL, ".tm_clone_table", 3);
5823 /* Helper comparison function for qsorting by the DECL_UID stored in
5824 alias_pair->emitted_diags. */
5826 static int
5827 tm_alias_pair_cmp (const void *x, const void *y)
5829 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
5830 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
5831 if (p1->uid < p2->uid)
5832 return -1;
5833 if (p1->uid > p2->uid)
5834 return 1;
5835 return 0;
5838 void
5839 finish_tm_clone_pairs (void)
5841 vec<tm_alias_pair> tm_alias_pairs = vNULL;
5843 if (tm_clone_hash == NULL)
5844 return;
5846 /* We need a determenistic order for the .tm_clone_table, otherwise
5847 we will get bootstrap comparison failures, so dump the hash table
5848 to a vector, sort it, and dump the vector. */
5850 /* Dump the hashtable to a vector. */
5851 htab_traverse_noresize (tm_clone_hash, dump_tm_clone_to_vec,
5852 (void *) &tm_alias_pairs);
5853 /* Sort it. */
5854 tm_alias_pairs.qsort (tm_alias_pair_cmp);
5856 /* Dump it. */
5857 dump_tm_clone_pairs (tm_alias_pairs);
5859 htab_delete (tm_clone_hash);
5860 tm_clone_hash = NULL;
5861 tm_alias_pairs.release ();
5865 /* Emit an assembler directive to set symbol for DECL visibility to
5866 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
5868 void
5869 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
5870 int vis ATTRIBUTE_UNUSED)
5872 #ifdef HAVE_GAS_HIDDEN
5873 static const char * const visibility_types[] = {
5874 NULL, "protected", "hidden", "internal"
5877 const char *name, *type;
5879 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5880 type = visibility_types[vis];
5882 fprintf (asm_out_file, "\t.%s\t", type);
5883 assemble_name (asm_out_file, name);
5884 fprintf (asm_out_file, "\n");
5885 #else
5886 if (!DECL_ARTIFICIAL (decl))
5887 warning (OPT_Wattributes, "visibility attribute not supported "
5888 "in this configuration; ignored");
5889 #endif
5892 /* A helper function to call assemble_visibility when needed for a decl. */
5895 maybe_assemble_visibility (tree decl)
5897 enum symbol_visibility vis = DECL_VISIBILITY (decl);
5899 if (vis != VISIBILITY_DEFAULT)
5901 targetm.asm_out.assemble_visibility (decl, vis);
5902 return 1;
5904 else
5905 return 0;
5908 /* Returns 1 if the target configuration supports defining public symbols
5909 so that one of them will be chosen at link time instead of generating a
5910 multiply-defined symbol error, whether through the use of weak symbols or
5911 a target-specific mechanism for having duplicates discarded. */
5914 supports_one_only (void)
5916 if (SUPPORTS_ONE_ONLY)
5917 return 1;
5918 return TARGET_SUPPORTS_WEAK;
5921 /* Set up DECL as a public symbol that can be defined in multiple
5922 translation units without generating a linker error. */
5924 void
5925 make_decl_one_only (tree decl, tree comdat_group)
5927 gcc_assert (TREE_CODE (decl) == VAR_DECL
5928 || TREE_CODE (decl) == FUNCTION_DECL);
5930 TREE_PUBLIC (decl) = 1;
5932 if (SUPPORTS_ONE_ONLY)
5934 #ifdef MAKE_DECL_ONE_ONLY
5935 MAKE_DECL_ONE_ONLY (decl);
5936 #endif
5937 DECL_COMDAT_GROUP (decl) = comdat_group;
5939 else if (TREE_CODE (decl) == VAR_DECL
5940 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node))
5941 DECL_COMMON (decl) = 1;
5942 else
5944 gcc_assert (TARGET_SUPPORTS_WEAK);
5945 DECL_WEAK (decl) = 1;
5949 void
5950 init_varasm_once (void)
5952 section_htab = htab_create_ggc (31, section_entry_hash,
5953 section_entry_eq, NULL);
5954 object_block_htab = htab_create_ggc (31, object_block_entry_hash,
5955 object_block_entry_eq, NULL);
5956 const_desc_htab = htab_create_ggc (1009, const_desc_hash,
5957 const_desc_eq, NULL);
5959 shared_constant_pool = create_constant_pool ();
5961 #ifdef TEXT_SECTION_ASM_OP
5962 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
5963 TEXT_SECTION_ASM_OP);
5964 #endif
5966 #ifdef DATA_SECTION_ASM_OP
5967 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5968 DATA_SECTION_ASM_OP);
5969 #endif
5971 #ifdef SDATA_SECTION_ASM_OP
5972 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5973 SDATA_SECTION_ASM_OP);
5974 #endif
5976 #ifdef READONLY_DATA_SECTION_ASM_OP
5977 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
5978 READONLY_DATA_SECTION_ASM_OP);
5979 #endif
5981 #ifdef CTORS_SECTION_ASM_OP
5982 ctors_section = get_unnamed_section (0, output_section_asm_op,
5983 CTORS_SECTION_ASM_OP);
5984 #endif
5986 #ifdef DTORS_SECTION_ASM_OP
5987 dtors_section = get_unnamed_section (0, output_section_asm_op,
5988 DTORS_SECTION_ASM_OP);
5989 #endif
5991 #ifdef BSS_SECTION_ASM_OP
5992 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5993 output_section_asm_op,
5994 BSS_SECTION_ASM_OP);
5995 #endif
5997 #ifdef SBSS_SECTION_ASM_OP
5998 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5999 output_section_asm_op,
6000 SBSS_SECTION_ASM_OP);
6001 #endif
6003 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6004 | SECTION_COMMON, emit_tls_common);
6005 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6006 | SECTION_COMMON, emit_local);
6007 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6008 | SECTION_COMMON, emit_common);
6010 #if defined ASM_OUTPUT_ALIGNED_BSS
6011 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
6012 emit_bss);
6013 #endif
6015 targetm.asm_out.init_sections ();
6017 if (readonly_data_section == NULL)
6018 readonly_data_section = text_section;
6020 #ifdef ASM_OUTPUT_EXTERNAL
6021 pending_assemble_externals_set = pointer_set_create ();
6022 #endif
6025 enum tls_model
6026 decl_default_tls_model (const_tree decl)
6028 enum tls_model kind;
6029 bool is_local;
6031 is_local = targetm.binds_local_p (decl);
6032 if (!flag_shlib)
6034 if (is_local)
6035 kind = TLS_MODEL_LOCAL_EXEC;
6036 else
6037 kind = TLS_MODEL_INITIAL_EXEC;
6040 /* Local dynamic is inefficient when we're not combining the
6041 parts of the address. */
6042 else if (optimize && is_local)
6043 kind = TLS_MODEL_LOCAL_DYNAMIC;
6044 else
6045 kind = TLS_MODEL_GLOBAL_DYNAMIC;
6046 if (kind < flag_tls_default)
6047 kind = flag_tls_default;
6049 return kind;
6052 /* Select a set of attributes for section NAME based on the properties
6053 of DECL and whether or not RELOC indicates that DECL's initializer
6054 might contain runtime relocations.
6056 We make the section read-only and executable for a function decl,
6057 read-only for a const data decl, and writable for a non-const data decl. */
6059 unsigned int
6060 default_section_type_flags (tree decl, const char *name, int reloc)
6062 unsigned int flags;
6064 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6065 flags = SECTION_CODE;
6066 else if (decl)
6068 enum section_category category
6069 = categorize_decl_for_section (decl, reloc);
6070 if (decl_readonly_section_1 (category))
6071 flags = 0;
6072 else if (category == SECCAT_DATA_REL_RO
6073 || category == SECCAT_DATA_REL_RO_LOCAL)
6074 flags = SECTION_WRITE | SECTION_RELRO;
6075 else
6076 flags = SECTION_WRITE;
6078 else
6080 flags = SECTION_WRITE;
6081 if (strcmp (name, ".data.rel.ro") == 0
6082 || strcmp (name, ".data.rel.ro.local") == 0)
6083 flags |= SECTION_RELRO;
6086 if (decl && DECL_P (decl) && DECL_ONE_ONLY (decl))
6087 flags |= SECTION_LINKONCE;
6089 if (strcmp (name, ".vtable_map_vars") == 0)
6090 flags |= SECTION_LINKONCE;
6092 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6093 flags |= SECTION_TLS | SECTION_WRITE;
6095 if (strcmp (name, ".bss") == 0
6096 || strncmp (name, ".bss.", 5) == 0
6097 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6098 || strcmp (name, ".sbss") == 0
6099 || strncmp (name, ".sbss.", 6) == 0
6100 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6101 flags |= SECTION_BSS;
6103 if (strcmp (name, ".tdata") == 0
6104 || strncmp (name, ".tdata.", 7) == 0
6105 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6106 flags |= SECTION_TLS;
6108 if (strcmp (name, ".tbss") == 0
6109 || strncmp (name, ".tbss.", 6) == 0
6110 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6111 flags |= SECTION_TLS | SECTION_BSS;
6113 /* These three sections have special ELF types. They are neither
6114 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
6115 want to print a section type (@progbits or @nobits). If someone
6116 is silly enough to emit code or TLS variables to one of these
6117 sections, then don't handle them specially. */
6118 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6119 && (strcmp (name, ".init_array") == 0
6120 || strcmp (name, ".fini_array") == 0
6121 || strcmp (name, ".preinit_array") == 0))
6122 flags |= SECTION_NOTYPE;
6124 return flags;
6127 /* Return true if the target supports some form of global BSS,
6128 either through bss_noswitch_section, or by selecting a BSS
6129 section in TARGET_ASM_SELECT_SECTION. */
6131 bool
6132 have_global_bss_p (void)
6134 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6137 /* Output assembly to switch to section NAME with attribute FLAGS.
6138 Four variants for common object file formats. */
6140 void
6141 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6142 unsigned int flags ATTRIBUTE_UNUSED,
6143 tree decl ATTRIBUTE_UNUSED)
6145 /* Some object formats don't support named sections at all. The
6146 front-end should already have flagged this as an error. */
6147 gcc_unreachable ();
6150 #ifndef TLS_SECTION_ASM_FLAG
6151 #define TLS_SECTION_ASM_FLAG 'T'
6152 #endif
6154 void
6155 default_elf_asm_named_section (const char *name, unsigned int flags,
6156 tree decl ATTRIBUTE_UNUSED)
6158 char flagchars[10], *f = flagchars;
6160 /* If we have already declared this section, we can use an
6161 abbreviated form to switch back to it -- unless this section is
6162 part of a COMDAT groups, in which case GAS requires the full
6163 declaration every time. */
6164 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6165 && (flags & SECTION_DECLARED))
6167 fprintf (asm_out_file, "\t.section\t%s\n", name);
6168 return;
6171 if (!(flags & SECTION_DEBUG))
6172 *f++ = 'a';
6173 if (flags & SECTION_EXCLUDE)
6174 *f++ = 'e';
6175 if (flags & SECTION_WRITE)
6176 *f++ = 'w';
6177 if (flags & SECTION_CODE)
6178 *f++ = 'x';
6179 if (flags & SECTION_SMALL)
6180 *f++ = 's';
6181 if (flags & SECTION_MERGE)
6182 *f++ = 'M';
6183 if (flags & SECTION_STRINGS)
6184 *f++ = 'S';
6185 if (flags & SECTION_TLS)
6186 *f++ = TLS_SECTION_ASM_FLAG;
6187 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6188 *f++ = 'G';
6189 *f = '\0';
6191 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6193 if (!(flags & SECTION_NOTYPE))
6195 const char *type;
6196 const char *format;
6198 if (flags & SECTION_BSS)
6199 type = "nobits";
6200 else
6201 type = "progbits";
6203 format = ",@%s";
6204 /* On platforms that use "@" as the assembly comment character,
6205 use "%" instead. */
6206 if (strcmp (ASM_COMMENT_START, "@") == 0)
6207 format = ",%%%s";
6208 fprintf (asm_out_file, format, type);
6210 if (flags & SECTION_ENTSIZE)
6211 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6212 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6214 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6215 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6216 else
6217 fprintf (asm_out_file, ",%s,comdat",
6218 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6222 putc ('\n', asm_out_file);
6225 void
6226 default_coff_asm_named_section (const char *name, unsigned int flags,
6227 tree decl ATTRIBUTE_UNUSED)
6229 char flagchars[8], *f = flagchars;
6231 if (flags & SECTION_WRITE)
6232 *f++ = 'w';
6233 if (flags & SECTION_CODE)
6234 *f++ = 'x';
6235 *f = '\0';
6237 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6240 void
6241 default_pe_asm_named_section (const char *name, unsigned int flags,
6242 tree decl)
6244 default_coff_asm_named_section (name, flags, decl);
6246 if (flags & SECTION_LINKONCE)
6248 /* Functions may have been compiled at various levels of
6249 optimization so we can't use `same_size' here.
6250 Instead, have the linker pick one. */
6251 fprintf (asm_out_file, "\t.linkonce %s\n",
6252 (flags & SECTION_CODE ? "discard" : "same_size"));
6256 /* The lame default section selector. */
6258 section *
6259 default_select_section (tree decl, int reloc,
6260 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6262 if (DECL_P (decl))
6264 if (decl_readonly_section (decl, reloc))
6265 return readonly_data_section;
6267 else if (TREE_CODE (decl) == CONSTRUCTOR)
6269 if (! ((flag_pic && reloc)
6270 || !TREE_READONLY (decl)
6271 || TREE_SIDE_EFFECTS (decl)
6272 || !TREE_CONSTANT (decl)))
6273 return readonly_data_section;
6275 else if (TREE_CODE (decl) == STRING_CST)
6276 return readonly_data_section;
6277 else if (! (flag_pic && reloc))
6278 return readonly_data_section;
6280 return data_section;
6283 enum section_category
6284 categorize_decl_for_section (const_tree decl, int reloc)
6286 enum section_category ret;
6288 if (TREE_CODE (decl) == FUNCTION_DECL)
6289 return SECCAT_TEXT;
6290 else if (TREE_CODE (decl) == STRING_CST)
6292 if ((flag_sanitize & SANITIZE_ADDRESS)
6293 && asan_protect_global (CONST_CAST_TREE (decl)))
6294 /* or !flag_merge_constants */
6295 return SECCAT_RODATA;
6296 else
6297 return SECCAT_RODATA_MERGE_STR;
6299 else if (TREE_CODE (decl) == VAR_DECL)
6301 if (bss_initializer_p (decl))
6302 ret = SECCAT_BSS;
6303 else if (! TREE_READONLY (decl)
6304 || TREE_SIDE_EFFECTS (decl)
6305 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
6307 /* Here the reloc_rw_mask is not testing whether the section should
6308 be read-only or not, but whether the dynamic link will have to
6309 do something. If so, we wish to segregate the data in order to
6310 minimize cache misses inside the dynamic linker. */
6311 if (reloc & targetm.asm_out.reloc_rw_mask ())
6312 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6313 else
6314 ret = SECCAT_DATA;
6316 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6317 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6318 else if (reloc || flag_merge_constants < 2
6319 || ((flag_sanitize & SANITIZE_ADDRESS)
6320 && asan_protect_global (CONST_CAST_TREE (decl))))
6321 /* C and C++ don't allow different variables to share the same
6322 location. -fmerge-all-constants allows even that (at the
6323 expense of not conforming). */
6324 ret = SECCAT_RODATA;
6325 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6326 ret = SECCAT_RODATA_MERGE_STR_INIT;
6327 else
6328 ret = SECCAT_RODATA_MERGE_CONST;
6330 else if (TREE_CODE (decl) == CONSTRUCTOR)
6332 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6333 || TREE_SIDE_EFFECTS (decl)
6334 || ! TREE_CONSTANT (decl))
6335 ret = SECCAT_DATA;
6336 else
6337 ret = SECCAT_RODATA;
6339 else
6340 ret = SECCAT_RODATA;
6342 /* There are no read-only thread-local sections. */
6343 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6345 /* Note that this would be *just* SECCAT_BSS, except that there's
6346 no concept of a read-only thread-local-data section. */
6347 if (ret == SECCAT_BSS
6348 || (flag_zero_initialized_in_bss
6349 && initializer_zerop (DECL_INITIAL (decl))))
6350 ret = SECCAT_TBSS;
6351 else
6352 ret = SECCAT_TDATA;
6355 /* If the target uses small data sections, select it. */
6356 else if (targetm.in_small_data_p (decl))
6358 if (ret == SECCAT_BSS)
6359 ret = SECCAT_SBSS;
6360 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6361 ret = SECCAT_SRODATA;
6362 else
6363 ret = SECCAT_SDATA;
6366 return ret;
6369 static bool
6370 decl_readonly_section_1 (enum section_category category)
6372 switch (category)
6374 case SECCAT_RODATA:
6375 case SECCAT_RODATA_MERGE_STR:
6376 case SECCAT_RODATA_MERGE_STR_INIT:
6377 case SECCAT_RODATA_MERGE_CONST:
6378 case SECCAT_SRODATA:
6379 return true;
6380 default:
6381 return false;
6385 bool
6386 decl_readonly_section (const_tree decl, int reloc)
6388 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6391 /* Select a section based on the above categorization. */
6393 section *
6394 default_elf_select_section (tree decl, int reloc,
6395 unsigned HOST_WIDE_INT align)
6397 const char *sname;
6398 switch (categorize_decl_for_section (decl, reloc))
6400 case SECCAT_TEXT:
6401 /* We're not supposed to be called on FUNCTION_DECLs. */
6402 gcc_unreachable ();
6403 case SECCAT_RODATA:
6404 return readonly_data_section;
6405 case SECCAT_RODATA_MERGE_STR:
6406 return mergeable_string_section (decl, align, 0);
6407 case SECCAT_RODATA_MERGE_STR_INIT:
6408 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6409 case SECCAT_RODATA_MERGE_CONST:
6410 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6411 case SECCAT_SRODATA:
6412 sname = ".sdata2";
6413 break;
6414 case SECCAT_DATA:
6415 return data_section;
6416 case SECCAT_DATA_REL:
6417 sname = ".data.rel";
6418 break;
6419 case SECCAT_DATA_REL_LOCAL:
6420 sname = ".data.rel.local";
6421 break;
6422 case SECCAT_DATA_REL_RO:
6423 sname = ".data.rel.ro";
6424 break;
6425 case SECCAT_DATA_REL_RO_LOCAL:
6426 sname = ".data.rel.ro.local";
6427 break;
6428 case SECCAT_SDATA:
6429 sname = ".sdata";
6430 break;
6431 case SECCAT_TDATA:
6432 sname = ".tdata";
6433 break;
6434 case SECCAT_BSS:
6435 if (bss_section)
6436 return bss_section;
6437 sname = ".bss";
6438 break;
6439 case SECCAT_SBSS:
6440 sname = ".sbss";
6441 break;
6442 case SECCAT_TBSS:
6443 sname = ".tbss";
6444 break;
6445 default:
6446 gcc_unreachable ();
6449 return get_named_section (decl, sname, reloc);
6452 /* Construct a unique section name based on the decl name and the
6453 categorization performed above. */
6455 void
6456 default_unique_section (tree decl, int reloc)
6458 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6459 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6460 const char *prefix, *name, *linkonce;
6461 char *string;
6463 switch (categorize_decl_for_section (decl, reloc))
6465 case SECCAT_TEXT:
6466 prefix = one_only ? ".t" : ".text";
6467 break;
6468 case SECCAT_RODATA:
6469 case SECCAT_RODATA_MERGE_STR:
6470 case SECCAT_RODATA_MERGE_STR_INIT:
6471 case SECCAT_RODATA_MERGE_CONST:
6472 prefix = one_only ? ".r" : ".rodata";
6473 break;
6474 case SECCAT_SRODATA:
6475 prefix = one_only ? ".s2" : ".sdata2";
6476 break;
6477 case SECCAT_DATA:
6478 prefix = one_only ? ".d" : ".data";
6479 break;
6480 case SECCAT_DATA_REL:
6481 prefix = one_only ? ".d.rel" : ".data.rel";
6482 break;
6483 case SECCAT_DATA_REL_LOCAL:
6484 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6485 break;
6486 case SECCAT_DATA_REL_RO:
6487 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6488 break;
6489 case SECCAT_DATA_REL_RO_LOCAL:
6490 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6491 break;
6492 case SECCAT_SDATA:
6493 prefix = one_only ? ".s" : ".sdata";
6494 break;
6495 case SECCAT_BSS:
6496 prefix = one_only ? ".b" : ".bss";
6497 break;
6498 case SECCAT_SBSS:
6499 prefix = one_only ? ".sb" : ".sbss";
6500 break;
6501 case SECCAT_TDATA:
6502 prefix = one_only ? ".td" : ".tdata";
6503 break;
6504 case SECCAT_TBSS:
6505 prefix = one_only ? ".tb" : ".tbss";
6506 break;
6507 default:
6508 gcc_unreachable ();
6511 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
6512 name = targetm.strip_name_encoding (name);
6514 /* If we're using one_only, then there needs to be a .gnu.linkonce
6515 prefix to the section name. */
6516 linkonce = one_only ? ".gnu.linkonce" : "";
6518 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6520 DECL_SECTION_NAME (decl) = build_string (strlen (string), string);
6523 /* Like compute_reloc_for_constant, except for an RTX. The return value
6524 is a mask for which bit 1 indicates a global relocation, and bit 0
6525 indicates a local relocation. */
6527 static int
6528 compute_reloc_for_rtx_1 (rtx *xp, void *data)
6530 int *preloc = (int *) data;
6531 rtx x = *xp;
6533 switch (GET_CODE (x))
6535 case SYMBOL_REF:
6536 *preloc |= SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6537 break;
6538 case LABEL_REF:
6539 *preloc |= 1;
6540 break;
6541 default:
6542 break;
6545 return 0;
6548 static int
6549 compute_reloc_for_rtx (rtx x)
6551 int reloc;
6553 switch (GET_CODE (x))
6555 case CONST:
6556 case SYMBOL_REF:
6557 case LABEL_REF:
6558 reloc = 0;
6559 for_each_rtx (&x, compute_reloc_for_rtx_1, &reloc);
6560 return reloc;
6562 default:
6563 return 0;
6567 section *
6568 default_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
6569 rtx x,
6570 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6572 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6573 return data_section;
6574 else
6575 return readonly_data_section;
6578 section *
6579 default_elf_select_rtx_section (enum machine_mode mode, rtx x,
6580 unsigned HOST_WIDE_INT align)
6582 int reloc = compute_reloc_for_rtx (x);
6584 /* ??? Handle small data here somehow. */
6586 if (reloc & targetm.asm_out.reloc_rw_mask ())
6588 if (reloc == 1)
6589 return get_named_section (NULL, ".data.rel.ro.local", 1);
6590 else
6591 return get_named_section (NULL, ".data.rel.ro", 3);
6594 return mergeable_constant_section (mode, align, 0);
6597 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6599 void
6600 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6602 rtx symbol;
6603 int flags;
6605 /* Careful not to prod global register variables. */
6606 if (!MEM_P (rtl))
6607 return;
6608 symbol = XEXP (rtl, 0);
6609 if (GET_CODE (symbol) != SYMBOL_REF)
6610 return;
6612 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6613 if (TREE_CODE (decl) == FUNCTION_DECL)
6614 flags |= SYMBOL_FLAG_FUNCTION;
6615 if (targetm.binds_local_p (decl))
6616 flags |= SYMBOL_FLAG_LOCAL;
6617 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6618 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6619 else if (targetm.in_small_data_p (decl))
6620 flags |= SYMBOL_FLAG_SMALL;
6621 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6622 being PUBLIC, the thing *must* be defined in this translation unit.
6623 Prevent this buglet from being propagated into rtl code as well. */
6624 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6625 flags |= SYMBOL_FLAG_EXTERNAL;
6627 SYMBOL_REF_FLAGS (symbol) = flags;
6630 /* By default, we do nothing for encode_section_info, so we need not
6631 do anything but discard the '*' marker. */
6633 const char *
6634 default_strip_name_encoding (const char *str)
6636 return str + (*str == '*');
6639 #ifdef ASM_OUTPUT_DEF
6640 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6641 anchor relative to ".", the current section position. */
6643 void
6644 default_asm_output_anchor (rtx symbol)
6646 char buffer[100];
6648 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6649 SYMBOL_REF_BLOCK_OFFSET (symbol));
6650 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6652 #endif
6654 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6656 bool
6657 default_use_anchors_for_symbol_p (const_rtx symbol)
6659 section *sect;
6660 tree decl;
6662 /* Don't use anchors for mergeable sections. The linker might move
6663 the objects around. */
6664 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6665 if (sect->common.flags & SECTION_MERGE)
6666 return false;
6668 /* Don't use anchors for small data sections. The small data register
6669 acts as an anchor for such sections. */
6670 if (sect->common.flags & SECTION_SMALL)
6671 return false;
6673 decl = SYMBOL_REF_DECL (symbol);
6674 if (decl && DECL_P (decl))
6676 /* Don't use section anchors for decls that might be defined or
6677 usurped by other modules. */
6678 if (TREE_PUBLIC (decl) && !decl_binds_to_current_def_p (decl))
6679 return false;
6681 /* Don't use section anchors for decls that will be placed in a
6682 small data section. */
6683 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6684 one above. The problem is that we only use SECTION_SMALL for
6685 sections that should be marked as small in the section directive. */
6686 if (targetm.in_small_data_p (decl))
6687 return false;
6689 return true;
6692 /* Return true when RESOLUTION indicate that symbol will be bound to the
6693 definition provided by current .o file. */
6695 static bool
6696 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
6698 return (resolution == LDPR_PREVAILING_DEF
6699 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6700 || resolution == LDPR_PREVAILING_DEF_IRONLY);
6703 /* Return true when RESOLUTION indicate that symbol will be bound locally
6704 within current executable or DSO. */
6706 static bool
6707 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
6709 return (resolution == LDPR_PREVAILING_DEF
6710 || resolution == LDPR_PREVAILING_DEF_IRONLY
6711 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6712 || resolution == LDPR_PREEMPTED_REG
6713 || resolution == LDPR_PREEMPTED_IR
6714 || resolution == LDPR_RESOLVED_IR
6715 || resolution == LDPR_RESOLVED_EXEC);
6718 /* Assume ELF-ish defaults, since that's pretty much the most liberal
6719 wrt cross-module name binding. */
6721 bool
6722 default_binds_local_p (const_tree exp)
6724 return default_binds_local_p_1 (exp, flag_shlib);
6727 bool
6728 default_binds_local_p_1 (const_tree exp, int shlib)
6730 bool local_p;
6731 bool resolved_locally = false;
6732 bool resolved_to_local_def = false;
6734 /* With resolution file in hands, take look into resolutions.
6735 We can't just return true for resolved_locally symbols,
6736 because dynamic linking might overwrite symbols
6737 in shared libraries. */
6738 if (TREE_CODE (exp) == VAR_DECL && TREE_PUBLIC (exp)
6739 && (TREE_STATIC (exp) || DECL_EXTERNAL (exp)))
6741 varpool_node *vnode = varpool_get_node (exp);
6742 if (vnode && (resolution_local_p (vnode->resolution) || vnode->in_other_partition))
6743 resolved_locally = true;
6744 if (vnode
6745 && resolution_to_local_definition_p (vnode->resolution))
6746 resolved_to_local_def = true;
6748 else if (TREE_CODE (exp) == FUNCTION_DECL && TREE_PUBLIC (exp))
6750 struct cgraph_node *node = cgraph_get_node (exp);
6751 if (node
6752 && (resolution_local_p (node->resolution) || node->in_other_partition))
6753 resolved_locally = true;
6754 if (node
6755 && resolution_to_local_definition_p (node->resolution))
6756 resolved_to_local_def = true;
6759 /* A non-decl is an entry in the constant pool. */
6760 if (!DECL_P (exp))
6761 local_p = true;
6762 /* Weakrefs may not bind locally, even though the weakref itself is always
6763 static and therefore local. Similarly, the resolver for ifunc functions
6764 might resolve to a non-local function.
6765 FIXME: We can resolve the weakref case more curefuly by looking at the
6766 weakref alias. */
6767 else if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
6768 || (TREE_CODE (exp) == FUNCTION_DECL
6769 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
6770 local_p = false;
6771 /* Static variables are always local. */
6772 else if (! TREE_PUBLIC (exp))
6773 local_p = true;
6774 /* A variable is local if the user has said explicitly that it will
6775 be. */
6776 else if ((DECL_VISIBILITY_SPECIFIED (exp)
6777 || resolved_to_local_def)
6778 && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6779 local_p = true;
6780 /* Variables defined outside this object might not be local. */
6781 else if (DECL_EXTERNAL (exp) && !resolved_locally)
6782 local_p = false;
6783 /* If defined in this object and visibility is not default, must be
6784 local. */
6785 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6786 local_p = true;
6787 /* Default visibility weak data can be overridden by a strong symbol
6788 in another module and so are not local. */
6789 else if (DECL_WEAK (exp)
6790 && !resolved_locally)
6791 local_p = false;
6792 /* If PIC, then assume that any global name can be overridden by
6793 symbols resolved from other modules. */
6794 else if (shlib)
6795 local_p = false;
6796 /* Uninitialized COMMON variable may be unified with symbols
6797 resolved from other modules. */
6798 else if (DECL_COMMON (exp)
6799 && !resolved_locally
6800 && (DECL_INITIAL (exp) == NULL
6801 || DECL_INITIAL (exp) == error_mark_node))
6802 local_p = false;
6803 /* Otherwise we're left with initialized (or non-common) global data
6804 which is of necessity defined locally. */
6805 else
6806 local_p = true;
6808 return local_p;
6811 /* Return true when references to DECL must bind to current definition in
6812 final executable.
6814 The condition is usually equivalent to whether the function binds to the
6815 current module (shared library or executable), that is to binds_local_p.
6816 We use this fact to avoid need for another target hook and implement
6817 the logic using binds_local_p and just special cases where
6818 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
6819 the weak definitions (that can be overwritten at linktime by other
6820 definition from different object file) and when resolution info is available
6821 we simply use the knowledge passed to us by linker plugin. */
6822 bool
6823 decl_binds_to_current_def_p (tree decl)
6825 gcc_assert (DECL_P (decl));
6826 if (!targetm.binds_local_p (decl))
6827 return false;
6828 if (!TREE_PUBLIC (decl))
6829 return true;
6830 /* When resolution is available, just use it. */
6831 if (TREE_CODE (decl) == VAR_DECL
6832 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl)))
6834 varpool_node *vnode = varpool_get_node (decl);
6835 if (vnode
6836 && vnode->resolution != LDPR_UNKNOWN)
6837 return resolution_to_local_definition_p (vnode->resolution);
6839 else if (TREE_CODE (decl) == FUNCTION_DECL)
6841 struct cgraph_node *node = cgraph_get_node (decl);
6842 if (node
6843 && node->resolution != LDPR_UNKNOWN)
6844 return resolution_to_local_definition_p (node->resolution);
6846 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
6847 binds locally but still can be overwritten), DECL_COMMON (can be merged
6848 with a non-common definition somewhere in the same module) or
6849 DECL_EXTERNAL.
6850 This rely on fact that binds_local_p behave as decl_replaceable_p
6851 for all other declaration types. */
6852 if (DECL_WEAK (decl))
6853 return false;
6854 if (DECL_COMMON (decl)
6855 && (DECL_INITIAL (decl) == NULL
6856 || DECL_INITIAL (decl) == error_mark_node))
6857 return false;
6858 if (DECL_EXTERNAL (decl))
6859 return false;
6860 return true;
6863 /* A replaceable function or variable is one which may be replaced
6864 at link-time with an entirely different definition, provided that the
6865 replacement has the same type. For example, functions declared
6866 with __attribute__((weak)) on most systems are replaceable.
6868 COMDAT functions are not replaceable, since all definitions of the
6869 function must be equivalent. It is important that COMDAT functions
6870 not be treated as replaceable so that use of C++ template
6871 instantiations is not penalized. */
6873 bool
6874 decl_replaceable_p (tree decl)
6876 gcc_assert (DECL_P (decl));
6877 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
6878 return false;
6879 return !decl_binds_to_current_def_p (decl);
6882 /* Default function to output code that will globalize a label. A
6883 target must define GLOBAL_ASM_OP or provide its own function to
6884 globalize a label. */
6885 #ifdef GLOBAL_ASM_OP
6886 void
6887 default_globalize_label (FILE * stream, const char *name)
6889 fputs (GLOBAL_ASM_OP, stream);
6890 assemble_name (stream, name);
6891 putc ('\n', stream);
6893 #endif /* GLOBAL_ASM_OP */
6895 /* Default function to output code that will globalize a declaration. */
6896 void
6897 default_globalize_decl_name (FILE * stream, tree decl)
6899 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
6900 targetm.asm_out.globalize_label (stream, name);
6903 /* Default function to output a label for unwind information. The
6904 default is to do nothing. A target that needs nonlocal labels for
6905 unwind information must provide its own function to do this. */
6906 void
6907 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
6908 tree decl ATTRIBUTE_UNUSED,
6909 int for_eh ATTRIBUTE_UNUSED,
6910 int empty ATTRIBUTE_UNUSED)
6914 /* Default function to output a label to divide up the exception table.
6915 The default is to do nothing. A target that needs/wants to divide
6916 up the table must provide it's own function to do this. */
6917 void
6918 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
6922 /* This is how to output an internal numbered label where PREFIX is
6923 the class of label and LABELNO is the number within the class. */
6925 void
6926 default_generate_internal_label (char *buf, const char *prefix,
6927 unsigned long labelno)
6929 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6932 /* This is how to output an internal numbered label where PREFIX is
6933 the class of label and LABELNO is the number within the class. */
6935 void
6936 default_internal_label (FILE *stream, const char *prefix,
6937 unsigned long labelno)
6939 char *const buf = (char *) alloca (40 + strlen (prefix));
6940 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6941 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
6945 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
6947 void
6948 default_asm_declare_constant_name (FILE *file, const char *name,
6949 const_tree exp ATTRIBUTE_UNUSED,
6950 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
6952 assemble_label (file, name);
6955 /* This is the default behavior at the beginning of a file. It's
6956 controlled by two other target-hook toggles. */
6957 void
6958 default_file_start (void)
6960 if (targetm.asm_file_start_app_off
6961 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
6962 fputs (ASM_APP_OFF, asm_out_file);
6964 if (targetm.asm_file_start_file_directive)
6965 output_file_directive (asm_out_file, main_input_filename);
6968 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
6969 which emits a special section directive used to indicate whether or
6970 not this object file needs an executable stack. This is primarily
6971 a GNU extension to ELF but could be used on other targets. */
6973 int trampolines_created;
6975 void
6976 file_end_indicate_exec_stack (void)
6978 unsigned int flags = SECTION_DEBUG;
6979 if (trampolines_created)
6980 flags |= SECTION_CODE;
6982 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
6985 /* Emit a special section directive to indicate that this object file
6986 was compiled with -fsplit-stack. This is used to let the linker
6987 detect calls between split-stack code and non-split-stack code, so
6988 that it can modify the split-stack code to allocate a sufficiently
6989 large stack. We emit another special section if there are any
6990 functions in this file which have the no_split_stack attribute, to
6991 prevent the linker from warning about being unable to convert the
6992 functions if they call non-split-stack code. */
6994 void
6995 file_end_indicate_split_stack (void)
6997 if (flag_split_stack)
6999 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
7000 NULL));
7001 if (saw_no_split_stack)
7002 switch_to_section (get_section (".note.GNU-no-split-stack",
7003 SECTION_DEBUG, NULL));
7007 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
7008 a get_unnamed_section callback. */
7010 void
7011 output_section_asm_op (const void *directive)
7013 fprintf (asm_out_file, "%s\n", (const char *) directive);
7016 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
7017 the current section is NEW_SECTION. */
7019 void
7020 switch_to_section (section *new_section)
7022 if (in_section == new_section)
7023 return;
7025 if (new_section->common.flags & SECTION_FORGET)
7026 in_section = NULL;
7027 else
7028 in_section = new_section;
7030 switch (SECTION_STYLE (new_section))
7032 case SECTION_NAMED:
7033 targetm.asm_out.named_section (new_section->named.name,
7034 new_section->named.common.flags,
7035 new_section->named.decl);
7036 break;
7038 case SECTION_UNNAMED:
7039 new_section->unnamed.callback (new_section->unnamed.data);
7040 break;
7042 case SECTION_NOSWITCH:
7043 gcc_unreachable ();
7044 break;
7047 new_section->common.flags |= SECTION_DECLARED;
7050 /* If block symbol SYMBOL has not yet been assigned an offset, place
7051 it at the end of its block. */
7053 void
7054 place_block_symbol (rtx symbol)
7056 unsigned HOST_WIDE_INT size, mask, offset;
7057 struct constant_descriptor_rtx *desc;
7058 unsigned int alignment;
7059 struct object_block *block;
7060 tree decl;
7062 gcc_assert (SYMBOL_REF_BLOCK (symbol));
7063 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7064 return;
7066 /* Work out the symbol's size and alignment. */
7067 if (CONSTANT_POOL_ADDRESS_P (symbol))
7069 desc = SYMBOL_REF_CONSTANT (symbol);
7070 alignment = desc->align;
7071 size = GET_MODE_SIZE (desc->mode);
7073 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7075 decl = SYMBOL_REF_DECL (symbol);
7076 alignment = DECL_ALIGN (decl);
7077 size = get_constant_size (DECL_INITIAL (decl));
7078 if ((flag_sanitize & SANITIZE_ADDRESS)
7079 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7080 && asan_protect_global (DECL_INITIAL (decl)))
7081 size += asan_red_zone_size (size);
7083 else
7085 decl = SYMBOL_REF_DECL (symbol);
7086 alignment = get_variable_align (decl);
7087 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7088 if ((flag_sanitize & SANITIZE_ADDRESS)
7089 && asan_protect_global (decl))
7091 size += asan_red_zone_size (size);
7092 alignment = MAX (alignment,
7093 ASAN_RED_ZONE_SIZE * BITS_PER_UNIT);
7097 /* Calculate the object's offset from the start of the block. */
7098 block = SYMBOL_REF_BLOCK (symbol);
7099 mask = alignment / BITS_PER_UNIT - 1;
7100 offset = (block->size + mask) & ~mask;
7101 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7103 /* Record the block's new alignment and size. */
7104 block->alignment = MAX (block->alignment, alignment);
7105 block->size = offset + size;
7107 vec_safe_push (block->objects, symbol);
7110 /* Return the anchor that should be used to address byte offset OFFSET
7111 from the first object in BLOCK. MODEL is the TLS model used
7112 to access it. */
7115 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7116 enum tls_model model)
7118 char label[100];
7119 unsigned int begin, middle, end;
7120 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7121 rtx anchor;
7123 /* Work out the anchor's offset. Use an offset of 0 for the first
7124 anchor so that we don't pessimize the case where we take the address
7125 of a variable at the beginning of the block. This is particularly
7126 useful when a block has only one variable assigned to it.
7128 We try to place anchors RANGE bytes apart, so there can then be
7129 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7130 a ptr_mode offset. With some target settings, the lowest such
7131 anchor might be out of range for the lowest ptr_mode offset;
7132 likewise the highest anchor for the highest offset. Use anchors
7133 at the extreme ends of the ptr_mode range in such cases.
7135 All arithmetic uses unsigned integers in order to avoid
7136 signed overflow. */
7137 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7138 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7139 range = max_offset - min_offset + 1;
7140 if (range == 0)
7141 offset = 0;
7142 else
7144 bias = 1 << (GET_MODE_BITSIZE (ptr_mode) - 1);
7145 if (offset < 0)
7147 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7148 delta -= delta % range;
7149 if (delta > bias)
7150 delta = bias;
7151 offset = (HOST_WIDE_INT) (-delta);
7153 else
7155 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7156 delta -= delta % range;
7157 if (delta > bias - 1)
7158 delta = bias - 1;
7159 offset = (HOST_WIDE_INT) delta;
7163 /* Do a binary search to see if there's already an anchor we can use.
7164 Set BEGIN to the new anchor's index if not. */
7165 begin = 0;
7166 end = vec_safe_length (block->anchors);
7167 while (begin != end)
7169 middle = (end + begin) / 2;
7170 anchor = (*block->anchors)[middle];
7171 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7172 end = middle;
7173 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7174 begin = middle + 1;
7175 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7176 end = middle;
7177 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7178 begin = middle + 1;
7179 else
7180 return anchor;
7183 /* Create a new anchor with a unique label. */
7184 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7185 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7186 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7187 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7189 /* Insert it at index BEGIN. */
7190 vec_safe_insert (block->anchors, begin, anchor);
7191 return anchor;
7194 /* Output the objects in BLOCK. */
7196 static void
7197 output_object_block (struct object_block *block)
7199 struct constant_descriptor_rtx *desc;
7200 unsigned int i;
7201 HOST_WIDE_INT offset;
7202 tree decl;
7203 rtx symbol;
7205 if (!block->objects)
7206 return;
7208 /* Switch to the section and make sure that the first byte is
7209 suitably aligned. */
7210 switch_to_section (block->sect);
7211 assemble_align (block->alignment);
7213 /* Define the values of all anchors relative to the current section
7214 position. */
7215 FOR_EACH_VEC_SAFE_ELT (block->anchors, i, symbol)
7216 targetm.asm_out.output_anchor (symbol);
7218 /* Output the objects themselves. */
7219 offset = 0;
7220 FOR_EACH_VEC_ELT (*block->objects, i, symbol)
7222 /* Move to the object's offset, padding with zeros if necessary. */
7223 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7224 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7225 if (CONSTANT_POOL_ADDRESS_P (symbol))
7227 desc = SYMBOL_REF_CONSTANT (symbol);
7228 output_constant_pool_1 (desc, 1);
7229 offset += GET_MODE_SIZE (desc->mode);
7231 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7233 HOST_WIDE_INT size;
7234 decl = SYMBOL_REF_DECL (symbol);
7235 assemble_constant_contents (DECL_INITIAL (decl), XSTR (symbol, 0),
7236 DECL_ALIGN (decl));
7237 size = get_constant_size (DECL_INITIAL (decl));
7238 offset += size;
7239 if ((flag_sanitize & SANITIZE_ADDRESS)
7240 && TREE_CODE (DECL_INITIAL (decl)) == STRING_CST
7241 && asan_protect_global (DECL_INITIAL (decl)))
7243 size = asan_red_zone_size (size);
7244 assemble_zeros (size);
7245 offset += size;
7248 else
7250 HOST_WIDE_INT size;
7251 decl = SYMBOL_REF_DECL (symbol);
7252 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7253 size = tree_to_uhwi (DECL_SIZE_UNIT (decl));
7254 offset += size;
7255 if ((flag_sanitize & SANITIZE_ADDRESS)
7256 && asan_protect_global (decl))
7258 size = asan_red_zone_size (size);
7259 assemble_zeros (size);
7260 offset += size;
7266 /* A htab_traverse callback used to call output_object_block for
7267 each member of object_block_htab. */
7269 static int
7270 output_object_block_htab (void **slot, void *data ATTRIBUTE_UNUSED)
7272 output_object_block ((struct object_block *) (*slot));
7273 return 1;
7276 /* Output the definitions of all object_blocks. */
7278 void
7279 output_object_blocks (void)
7281 htab_traverse (object_block_htab, output_object_block_htab, NULL);
7284 /* This function provides a possible implementation of the
7285 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7286 by -frecord-gcc-switches it creates a new mergeable, string section in the
7287 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7288 contains the switches in ASCII format.
7290 FIXME: This code does not correctly handle double quote characters
7291 that appear inside strings, (it strips them rather than preserving them).
7292 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7293 characters - instead it treats them as sub-string separators. Since
7294 we want to emit NUL strings terminators into the object file we have to use
7295 ASM_OUTPUT_SKIP. */
7298 elf_record_gcc_switches (print_switch_type type, const char * name)
7300 switch (type)
7302 case SWITCH_TYPE_PASSED:
7303 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7304 ASM_OUTPUT_SKIP (asm_out_file, (unsigned HOST_WIDE_INT) 1);
7305 break;
7307 case SWITCH_TYPE_DESCRIPTIVE:
7308 if (name == NULL)
7310 /* Distinguish between invocations where name is NULL. */
7311 static bool started = false;
7313 if (!started)
7315 section * sec;
7317 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7318 SECTION_DEBUG
7319 | SECTION_MERGE
7320 | SECTION_STRINGS
7321 | (SECTION_ENTSIZE & 1),
7322 NULL);
7323 switch_to_section (sec);
7324 started = true;
7328 default:
7329 break;
7332 /* The return value is currently ignored by the caller, but must be 0.
7333 For -fverbose-asm the return value would be the number of characters
7334 emitted into the assembler file. */
7335 return 0;
7338 /* Emit text to declare externally defined symbols. It is needed to
7339 properly support non-default visibility. */
7340 void
7341 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7342 tree decl,
7343 const char *name ATTRIBUTE_UNUSED)
7345 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7346 set in order to avoid putting out names that are never really
7347 used. */
7348 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7349 && targetm.binds_local_p (decl))
7350 maybe_assemble_visibility (decl);
7353 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7355 void
7356 default_asm_output_source_filename (FILE *file, const char *name)
7358 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7359 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7360 #else
7361 fprintf (file, "\t.file\t");
7362 output_quoted_string (file, name);
7363 putc ('\n', file);
7364 #endif
7367 /* Output a file name in the form wanted by System V. */
7369 void
7370 output_file_directive (FILE *asm_file, const char *input_name)
7372 int len;
7373 const char *na;
7375 if (input_name == NULL)
7376 input_name = "<stdin>";
7377 else
7378 input_name = remap_debug_filename (input_name);
7380 len = strlen (input_name);
7381 na = input_name + len;
7383 /* NA gets INPUT_NAME sans directory names. */
7384 while (na > input_name)
7386 if (IS_DIR_SEPARATOR (na[-1]))
7387 break;
7388 na--;
7391 targetm.asm_out.output_source_filename (asm_file, na);
7394 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7395 EXP. */
7397 make_debug_expr_from_rtl (const_rtx exp)
7399 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7400 enum machine_mode mode = GET_MODE (exp);
7401 rtx dval;
7403 DECL_ARTIFICIAL (ddecl) = 1;
7404 if (REG_P (exp) && REG_EXPR (exp))
7405 type = TREE_TYPE (REG_EXPR (exp));
7406 else if (MEM_P (exp) && MEM_EXPR (exp))
7407 type = TREE_TYPE (MEM_EXPR (exp));
7408 else
7409 type = NULL_TREE;
7410 if (type && TYPE_MODE (type) == mode)
7411 TREE_TYPE (ddecl) = type;
7412 else
7413 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7414 DECL_MODE (ddecl) = mode;
7415 dval = gen_rtx_DEBUG_EXPR (mode);
7416 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7417 SET_DECL_RTL (ddecl, dval);
7418 return dval;
7421 #ifdef ELF_ASCII_ESCAPES
7422 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7424 void
7425 default_elf_asm_output_limited_string (FILE *f, const char *s)
7427 int escape;
7428 unsigned char c;
7430 fputs (STRING_ASM_OP, f);
7431 putc ('"', f);
7432 while (*s != '\0')
7434 c = *s;
7435 escape = ELF_ASCII_ESCAPES[c];
7436 switch (escape)
7438 case 0:
7439 putc (c, f);
7440 break;
7441 case 1:
7442 /* TODO: Print in hex with fast function, important for -flto. */
7443 fprintf (f, "\\%03o", c);
7444 break;
7445 default:
7446 putc ('\\', f);
7447 putc (escape, f);
7448 break;
7450 s++;
7452 putc ('\"', f);
7453 putc ('\n', f);
7456 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7458 void
7459 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7461 const char *limit = s + len;
7462 const char *last_null = NULL;
7463 unsigned bytes_in_chunk = 0;
7464 unsigned char c;
7465 int escape;
7467 for (; s < limit; s++)
7469 const char *p;
7471 if (bytes_in_chunk >= 60)
7473 putc ('\"', f);
7474 putc ('\n', f);
7475 bytes_in_chunk = 0;
7478 if (s > last_null)
7480 for (p = s; p < limit && *p != '\0'; p++)
7481 continue;
7482 last_null = p;
7484 else
7485 p = last_null;
7487 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7489 if (bytes_in_chunk > 0)
7491 putc ('\"', f);
7492 putc ('\n', f);
7493 bytes_in_chunk = 0;
7496 default_elf_asm_output_limited_string (f, s);
7497 s = p;
7499 else
7501 if (bytes_in_chunk == 0)
7502 fputs (ASCII_DATA_ASM_OP "\"", f);
7504 c = *s;
7505 escape = ELF_ASCII_ESCAPES[c];
7506 switch (escape)
7508 case 0:
7509 putc (c, f);
7510 bytes_in_chunk++;
7511 break;
7512 case 1:
7513 /* TODO: Print in hex with fast function, important for -flto. */
7514 fprintf (f, "\\%03o", c);
7515 bytes_in_chunk += 4;
7516 break;
7517 default:
7518 putc ('\\', f);
7519 putc (escape, f);
7520 bytes_in_chunk += 2;
7521 break;
7527 if (bytes_in_chunk > 0)
7529 putc ('\"', f);
7530 putc ('\n', f);
7533 #endif
7535 static GTY(()) section *elf_init_array_section;
7536 static GTY(()) section *elf_fini_array_section;
7538 static section *
7539 get_elf_initfini_array_priority_section (int priority,
7540 bool constructor_p)
7542 section *sec;
7543 if (priority != DEFAULT_INIT_PRIORITY)
7545 char buf[18];
7546 sprintf (buf, "%s.%.5u",
7547 constructor_p ? ".init_array" : ".fini_array",
7548 priority);
7549 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7551 else
7553 if (constructor_p)
7555 if (elf_init_array_section == NULL)
7556 elf_init_array_section
7557 = get_section (".init_array",
7558 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7559 sec = elf_init_array_section;
7561 else
7563 if (elf_fini_array_section == NULL)
7564 elf_fini_array_section
7565 = get_section (".fini_array",
7566 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7567 sec = elf_fini_array_section;
7570 return sec;
7573 /* Use .init_array section for constructors. */
7575 void
7576 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7578 section *sec = get_elf_initfini_array_priority_section (priority,
7579 true);
7580 assemble_addr_to_section (symbol, sec);
7583 /* Use .fini_array section for destructors. */
7585 void
7586 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7588 section *sec = get_elf_initfini_array_priority_section (priority,
7589 false);
7590 assemble_addr_to_section (symbol, sec);
7593 /* Default TARGET_ASM_OUTPUT_IDENT hook.
7595 This is a bit of a cheat. The real default is a no-op, but this
7596 hook is the default for all targets with a .ident directive. */
7598 void
7599 default_asm_output_ident_directive (const char *ident_str)
7601 const char *ident_asm_op = "\t.ident\t";
7603 /* If we are still in the front end, do not write out the string
7604 to asm_out_file. Instead, add a fake top-level asm statement.
7605 This allows the front ends to use this hook without actually
7606 writing to asm_out_file, to handle #ident or Pragma Ident. */
7607 if (cgraph_state == CGRAPH_STATE_PARSING)
7609 char *buf = ACONCAT ((ident_asm_op, "\"", ident_str, "\"\n", NULL));
7610 add_asm_node (build_string (strlen (buf), buf));
7612 else
7613 fprintf (asm_out_file, "%s\"%s\"\n", ident_asm_op, ident_str);
7616 #include "gt-varasm.h"