2012-05-01 François Dumont <fdumont@gcc.gnu.org>
[official-gcc.git] / gcc / varasm.c
blob03ac49b4677d691030919aa41601af82e4095097
1 /* Output variables, constants and external declarations, for GNU compiler.
2 Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009,
4 2010, 2011, 2012 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
11 version.
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
16 for more details.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
23 /* This file handles generation of all the assembler code
24 *except* the instructions of a function.
25 This includes declarations of variables and their initial values.
27 We also output the assembler code for constants stored in memory
28 and are responsible for combining constants with the same value. */
30 #include "config.h"
31 #include "system.h"
32 #include "coretypes.h"
33 #include "tm.h"
34 #include "rtl.h"
35 #include "tree.h"
36 #include "flags.h"
37 #include "function.h"
38 #include "expr.h"
39 #include "hard-reg-set.h"
40 #include "regs.h"
41 #include "output.h"
42 #include "diagnostic-core.h"
43 #include "hashtab.h"
44 #include "ggc.h"
45 #include "langhooks.h"
46 #include "tm_p.h"
47 #include "debug.h"
48 #include "target.h"
49 #include "common/common-target.h"
50 #include "targhooks.h"
51 #include "tree-mudflap.h"
52 #include "cgraph.h"
53 #include "cfglayout.h"
54 #include "basic-block.h"
55 #include "tree-iterator.h"
56 #include "pointer-set.h"
58 #ifdef XCOFF_DEBUGGING_INFO
59 #include "xcoffout.h" /* Needed for external data
60 declarations for e.g. AIX 4.x. */
61 #endif
63 /* The (assembler) name of the first globally-visible object output. */
64 extern GTY(()) const char *first_global_object_name;
65 extern GTY(()) const char *weak_global_object_name;
67 const char *first_global_object_name;
68 const char *weak_global_object_name;
70 struct addr_const;
71 struct constant_descriptor_rtx;
72 struct rtx_constant_pool;
74 #define n_deferred_constants (crtl->varasm.deferred_constants)
76 /* Number for making the label on the next
77 constant that is stored in memory. */
79 static GTY(()) int const_labelno;
81 /* Carry information from ASM_DECLARE_OBJECT_NAME
82 to ASM_FINISH_DECLARE_OBJECT. */
84 int size_directive_output;
86 /* The last decl for which assemble_variable was called,
87 if it did ASM_DECLARE_OBJECT_NAME.
88 If the last call to assemble_variable didn't do that,
89 this holds 0. */
91 tree last_assemble_variable_decl;
93 /* The following global variable indicates if the first basic block
94 in a function belongs to the cold partition or not. */
96 bool first_function_block_is_cold;
98 /* We give all constants their own alias set. Perhaps redundant with
99 MEM_READONLY_P, but pre-dates it. */
101 static alias_set_type const_alias_set;
103 /* Whether we saw any functions with no_split_stack. */
105 static bool saw_no_split_stack;
107 static const char *strip_reg_name (const char *);
108 static int contains_pointers_p (tree);
109 #ifdef ASM_OUTPUT_EXTERNAL
110 static bool incorporeal_function_p (tree);
111 #endif
112 static void decode_addr_const (tree, struct addr_const *);
113 static hashval_t const_desc_hash (const void *);
114 static int const_desc_eq (const void *, const void *);
115 static hashval_t const_hash_1 (const tree);
116 static int compare_constant (const tree, const tree);
117 static tree copy_constant (tree);
118 static void output_constant_def_contents (rtx);
119 static void output_addressed_constants (tree);
120 static unsigned HOST_WIDE_INT array_size_for_constructor (tree);
121 static unsigned min_align (unsigned, unsigned);
122 static void globalize_decl (tree);
123 static bool decl_readonly_section_1 (enum section_category);
124 #ifdef BSS_SECTION_ASM_OP
125 #ifdef ASM_OUTPUT_ALIGNED_BSS
126 static void asm_output_aligned_bss (FILE *, tree, const char *,
127 unsigned HOST_WIDE_INT, int)
128 ATTRIBUTE_UNUSED;
129 #endif
130 #endif /* BSS_SECTION_ASM_OP */
131 static void mark_weak (tree);
132 static void output_constant_pool (const char *, tree);
134 /* Well-known sections, each one associated with some sort of *_ASM_OP. */
135 section *text_section;
136 section *data_section;
137 section *readonly_data_section;
138 section *sdata_section;
139 section *ctors_section;
140 section *dtors_section;
141 section *bss_section;
142 section *sbss_section;
144 /* Various forms of common section. All are guaranteed to be nonnull. */
145 section *tls_comm_section;
146 section *comm_section;
147 section *lcomm_section;
149 /* A SECTION_NOSWITCH section used for declaring global BSS variables.
150 May be null. */
151 section *bss_noswitch_section;
153 /* The section that holds the main exception table, when known. The section
154 is set either by the target's init_sections hook or by the first call to
155 switch_to_exception_section. */
156 section *exception_section;
158 /* The section that holds the DWARF2 frame unwind information, when known.
159 The section is set either by the target's init_sections hook or by the
160 first call to switch_to_eh_frame_section. */
161 section *eh_frame_section;
163 /* asm_out_file's current section. This is NULL if no section has yet
164 been selected or if we lose track of what the current section is. */
165 section *in_section;
167 /* True if code for the current function is currently being directed
168 at the cold section. */
169 bool in_cold_section_p;
171 /* A linked list of all the unnamed sections. */
172 static GTY(()) section *unnamed_sections;
174 /* Return a nonzero value if DECL has a section attribute. */
175 #define IN_NAMED_SECTION(DECL) \
176 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \
177 && DECL_SECTION_NAME (DECL) != NULL_TREE)
179 /* Hash table of named sections. */
180 static GTY((param_is (section))) htab_t section_htab;
182 /* A table of object_blocks, indexed by section. */
183 static GTY((param_is (struct object_block))) htab_t object_block_htab;
185 /* The next number to use for internal anchor labels. */
186 static GTY(()) int anchor_labelno;
188 /* A pool of constants that can be shared between functions. */
189 static GTY(()) struct rtx_constant_pool *shared_constant_pool;
191 /* Helper routines for maintaining section_htab. */
193 static int
194 section_entry_eq (const void *p1, const void *p2)
196 const section *old = (const section *) p1;
197 const char *new_name = (const char *) p2;
199 return strcmp (old->named.name, new_name) == 0;
202 static hashval_t
203 section_entry_hash (const void *p)
205 const section *old = (const section *) p;
206 return htab_hash_string (old->named.name);
209 /* Return a hash value for section SECT. */
211 static hashval_t
212 hash_section (section *sect)
214 if (sect->common.flags & SECTION_NAMED)
215 return htab_hash_string (sect->named.name);
216 return sect->common.flags;
219 /* Helper routines for maintaining object_block_htab. */
221 static int
222 object_block_entry_eq (const void *p1, const void *p2)
224 const struct object_block *old = (const struct object_block *) p1;
225 const section *new_section = (const section *) p2;
227 return old->sect == new_section;
230 static hashval_t
231 object_block_entry_hash (const void *p)
233 const struct object_block *old = (const struct object_block *) p;
234 return hash_section (old->sect);
237 /* Return a new unnamed section with the given fields. */
239 section *
240 get_unnamed_section (unsigned int flags, void (*callback) (const void *),
241 const void *data)
243 section *sect;
245 sect = ggc_alloc_section ();
246 sect->unnamed.common.flags = flags | SECTION_UNNAMED;
247 sect->unnamed.callback = callback;
248 sect->unnamed.data = data;
249 sect->unnamed.next = unnamed_sections;
251 unnamed_sections = sect;
252 return sect;
255 /* Return a SECTION_NOSWITCH section with the given fields. */
257 static section *
258 get_noswitch_section (unsigned int flags, noswitch_section_callback callback)
260 section *sect;
262 sect = ggc_alloc_section ();
263 sect->noswitch.common.flags = flags | SECTION_NOSWITCH;
264 sect->noswitch.callback = callback;
266 return sect;
269 /* Return the named section structure associated with NAME. Create
270 a new section with the given fields if no such structure exists. */
272 section *
273 get_section (const char *name, unsigned int flags, tree decl)
275 section *sect, **slot;
277 slot = (section **)
278 htab_find_slot_with_hash (section_htab, name,
279 htab_hash_string (name), INSERT);
280 flags |= SECTION_NAMED;
281 if (*slot == NULL)
283 sect = ggc_alloc_section ();
284 sect->named.common.flags = flags;
285 sect->named.name = ggc_strdup (name);
286 sect->named.decl = decl;
287 *slot = sect;
289 else
291 sect = *slot;
292 if ((sect->common.flags & ~SECTION_DECLARED) != flags
293 && ((sect->common.flags | flags) & SECTION_OVERRIDE) == 0)
295 /* It is fine if one of the section flags is
296 SECTION_WRITE | SECTION_RELRO and the other has none of these
297 flags (i.e. read-only) in named sections and either the
298 section hasn't been declared yet or has been declared as writable.
299 In that case just make sure the resulting flags are
300 SECTION_WRITE | SECTION_RELRO, ie. writable only because of
301 relocations. */
302 if (((sect->common.flags ^ flags) & (SECTION_WRITE | SECTION_RELRO))
303 == (SECTION_WRITE | SECTION_RELRO)
304 && (sect->common.flags
305 & ~(SECTION_DECLARED | SECTION_WRITE | SECTION_RELRO))
306 == (flags & ~(SECTION_WRITE | SECTION_RELRO))
307 && ((sect->common.flags & SECTION_DECLARED) == 0
308 || (sect->common.flags & SECTION_WRITE)))
310 sect->common.flags |= (SECTION_WRITE | SECTION_RELRO);
311 return sect;
313 /* Sanity check user variables for flag changes. */
314 if (decl == 0)
315 decl = sect->named.decl;
316 gcc_assert (decl);
317 if (sect->named.decl == NULL)
318 error ("%+D causes a section type conflict", decl);
319 else
321 error ("%+D causes a section type conflict with %D",
322 decl, sect->named.decl);
323 if (decl != sect->named.decl)
324 inform (DECL_SOURCE_LOCATION (sect->named.decl),
325 "%qD was declared here", sect->named.decl);
327 /* Make sure we don't error about one section multiple times. */
328 sect->common.flags |= SECTION_OVERRIDE;
331 return sect;
334 /* Return true if the current compilation mode benefits from having
335 objects grouped into blocks. */
337 static bool
338 use_object_blocks_p (void)
340 return flag_section_anchors;
343 /* Return the object_block structure for section SECT. Create a new
344 structure if we haven't created one already. Return null if SECT
345 itself is null. */
347 static struct object_block *
348 get_block_for_section (section *sect)
350 struct object_block *block;
351 void **slot;
353 if (sect == NULL)
354 return NULL;
356 slot = htab_find_slot_with_hash (object_block_htab, sect,
357 hash_section (sect), INSERT);
358 block = (struct object_block *) *slot;
359 if (block == NULL)
361 block = ggc_alloc_cleared_object_block ();
362 block->sect = sect;
363 *slot = block;
365 return block;
368 /* Create a symbol with label LABEL and place it at byte offset
369 OFFSET in BLOCK. OFFSET can be negative if the symbol's offset
370 is not yet known. LABEL must be a garbage-collected string. */
372 static rtx
373 create_block_symbol (const char *label, struct object_block *block,
374 HOST_WIDE_INT offset)
376 rtx symbol;
377 unsigned int size;
379 /* Create the extended SYMBOL_REF. */
380 size = RTX_HDR_SIZE + sizeof (struct block_symbol);
381 symbol = ggc_alloc_zone_rtx_def (size, &rtl_zone);
383 /* Initialize the normal SYMBOL_REF fields. */
384 memset (symbol, 0, size);
385 PUT_CODE (symbol, SYMBOL_REF);
386 PUT_MODE (symbol, Pmode);
387 XSTR (symbol, 0) = label;
388 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_HAS_BLOCK_INFO;
390 /* Initialize the block_symbol stuff. */
391 SYMBOL_REF_BLOCK (symbol) = block;
392 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
394 return symbol;
397 /* Return a section with a particular name and with whatever SECTION_*
398 flags section_type_flags deems appropriate. The name of the section
399 is taken from NAME if nonnull, otherwise it is taken from DECL's
400 DECL_SECTION_NAME. DECL is the decl associated with the section
401 (see the section comment for details) and RELOC is as for
402 section_type_flags. */
404 section *
405 get_named_section (tree decl, const char *name, int reloc)
407 unsigned int flags;
409 gcc_assert (!decl || DECL_P (decl));
410 if (name == NULL)
411 name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
413 flags = targetm.section_type_flags (decl, name, reloc);
415 return get_section (name, flags, decl);
418 /* If required, set DECL_SECTION_NAME to a unique name. */
420 void
421 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
422 int flag_function_or_data_sections)
424 if (DECL_SECTION_NAME (decl) == NULL_TREE
425 && targetm_common.have_named_sections
426 && (flag_function_or_data_sections
427 || DECL_ONE_ONLY (decl)))
429 targetm.asm_out.unique_section (decl, reloc);
430 DECL_HAS_IMPLICIT_SECTION_NAME_P (decl) = true;
434 #ifdef BSS_SECTION_ASM_OP
436 #ifdef ASM_OUTPUT_ALIGNED_BSS
438 /* Utility function for targets to use in implementing
439 ASM_OUTPUT_ALIGNED_BSS.
440 ??? It is believed that this function will work in most cases so such
441 support is localized here. */
443 static void
444 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
445 const char *name, unsigned HOST_WIDE_INT size,
446 int align)
448 switch_to_section (bss_section);
449 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
450 #ifdef ASM_DECLARE_OBJECT_NAME
451 last_assemble_variable_decl = decl;
452 ASM_DECLARE_OBJECT_NAME (file, name, decl);
453 #else
454 /* Standard thing is just output label for the object. */
455 ASM_OUTPUT_LABEL (file, name);
456 #endif /* ASM_DECLARE_OBJECT_NAME */
457 ASM_OUTPUT_SKIP (file, size ? size : 1);
460 #endif
462 #endif /* BSS_SECTION_ASM_OP */
464 #ifndef USE_SELECT_SECTION_FOR_FUNCTIONS
465 /* Return the hot section for function DECL. Return text_section for
466 null DECLs. */
468 static section *
469 hot_function_section (tree decl)
471 if (decl != NULL_TREE
472 && DECL_SECTION_NAME (decl) != NULL_TREE
473 && targetm_common.have_named_sections)
474 return get_named_section (decl, NULL, 0);
475 else
476 return text_section;
478 #endif
480 /* Return section for TEXT_SECTION_NAME if DECL or DECL_SECTION_NAME (DECL)
481 is NULL.
483 When DECL_SECTION_NAME is non-NULL and it is implicit section and
484 NAMED_SECTION_SUFFIX is non-NULL, then produce section called
485 concatenate the name with NAMED_SECTION_SUFFIX.
486 Otherwise produce "TEXT_SECTION_NAME.IMPLICIT_NAME". */
488 section *
489 get_named_text_section (tree decl,
490 const char *text_section_name,
491 const char *named_section_suffix)
493 if (decl && DECL_SECTION_NAME (decl))
495 if (named_section_suffix)
497 tree dsn = DECL_SECTION_NAME (decl);
498 const char *stripped_name;
499 char *name, *buffer;
501 name = (char *) alloca (TREE_STRING_LENGTH (dsn) + 1);
502 memcpy (name, TREE_STRING_POINTER (dsn),
503 TREE_STRING_LENGTH (dsn) + 1);
505 stripped_name = targetm.strip_name_encoding (name);
507 buffer = ACONCAT ((stripped_name, named_section_suffix, NULL));
508 return get_named_section (decl, buffer, 0);
510 else if (DECL_HAS_IMPLICIT_SECTION_NAME_P (decl))
512 const char *name;
514 /* Do not try to split gnu_linkonce functions. This gets somewhat
515 slipperly. */
516 if (DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP)
517 return NULL;
518 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
519 name = targetm.strip_name_encoding (name);
520 return get_named_section (decl, ACONCAT ((text_section_name, ".",
521 name, NULL)), 0);
523 else
524 return NULL;
526 return get_named_section (decl, text_section_name, 0);
529 /* Choose named function section based on its frequency. */
531 section *
532 default_function_section (tree decl, enum node_frequency freq,
533 bool startup, bool exit)
535 #if defined HAVE_LD_EH_GC_SECTIONS && defined HAVE_LD_EH_GC_SECTIONS_BUG
536 /* Old GNU linkers have buggy --gc-section support, which sometimes
537 results in .gcc_except_table* sections being garbage collected. */
538 if (decl
539 && DECL_SECTION_NAME (decl)
540 && DECL_HAS_IMPLICIT_SECTION_NAME_P (decl))
541 return NULL;
542 #endif
544 if (!flag_reorder_functions
545 || !targetm_common.have_named_sections)
546 return NULL;
547 /* Startup code should go to startup subsection unless it is
548 unlikely executed (this happens especially with function splitting
549 where we can split away unnecesary parts of static constructors. */
550 if (startup && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
551 return get_named_text_section (decl, ".text.startup", NULL);
553 /* Similarly for exit. */
554 if (exit && freq != NODE_FREQUENCY_UNLIKELY_EXECUTED)
555 return get_named_text_section (decl, ".text.exit", NULL);
557 /* Group cold functions together, similarly for hot code. */
558 switch (freq)
560 case NODE_FREQUENCY_UNLIKELY_EXECUTED:
561 return get_named_text_section (decl, ".text.unlikely", NULL);
562 case NODE_FREQUENCY_HOT:
563 return get_named_text_section (decl, ".text.hot", NULL);
564 default:
565 return NULL;
569 /* Return the section for function DECL.
571 If DECL is NULL_TREE, return the text section. We can be passed
572 NULL_TREE under some circumstances by dbxout.c at least.
574 If FORCE_COLD is true, return cold function section ignoring
575 the frequency info of cgraph_node. */
577 static section *
578 function_section_1 (tree decl, bool force_cold)
580 section *section = NULL;
581 enum node_frequency freq = NODE_FREQUENCY_NORMAL;
582 bool startup = false, exit = false;
584 if (decl)
586 struct cgraph_node *node = cgraph_get_node (decl);
588 if (node)
590 freq = node->frequency;
591 startup = node->only_called_at_startup;
592 exit = node->only_called_at_exit;
595 if (force_cold)
596 freq = NODE_FREQUENCY_UNLIKELY_EXECUTED;
598 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
599 if (decl != NULL_TREE
600 && DECL_SECTION_NAME (decl) != NULL_TREE)
602 if (targetm.asm_out.function_section)
603 section = targetm.asm_out.function_section (decl, freq,
604 startup, exit);
605 if (section)
606 return section;
607 return get_named_section (decl, NULL, 0);
609 else
610 return targetm.asm_out.select_section
611 (decl, freq == NODE_FREQUENCY_UNLIKELY_EXECUTED,
612 DECL_ALIGN (decl));
613 #else
614 if (targetm.asm_out.function_section)
615 section = targetm.asm_out.function_section (decl, freq, startup, exit);
616 if (section)
617 return section;
618 return hot_function_section (decl);
619 #endif
622 /* Return the section for function DECL.
624 If DECL is NULL_TREE, return the text section. We can be passed
625 NULL_TREE under some circumstances by dbxout.c at least. */
627 section *
628 function_section (tree decl)
630 /* Handle cases where function splitting code decides
631 to put function entry point into unlikely executed section
632 despite the fact that the function itself is not cold
633 (i.e. it is called rarely but contains a hot loop that is
634 better to live in hot subsection for the code locality). */
635 return function_section_1 (decl,
636 first_function_block_is_cold);
639 /* Return the section for the current function, take IN_COLD_SECTION_P
640 into account. */
642 section *
643 current_function_section (void)
645 return function_section_1 (current_function_decl, in_cold_section_p);
648 /* Tell assembler to switch to unlikely-to-be-executed text section. */
650 section *
651 unlikely_text_section (void)
653 return function_section_1 (current_function_decl, true);
656 /* When called within a function context, return true if the function
657 has been assigned a cold text section and if SECT is that section.
658 When called outside a function context, return true if SECT is the
659 default cold section. */
661 bool
662 unlikely_text_section_p (section *sect)
664 return sect == function_section_1 (current_function_decl, true);
667 /* Return the read-only data section associated with function DECL. */
669 section *
670 default_function_rodata_section (tree decl)
672 if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
674 const char *name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
676 if (DECL_ONE_ONLY (decl) && HAVE_COMDAT_GROUP)
678 const char *dot;
679 size_t len;
680 char* rname;
682 dot = strchr (name + 1, '.');
683 if (!dot)
684 dot = name;
685 len = strlen (dot) + 8;
686 rname = (char *) alloca (len);
688 strcpy (rname, ".rodata");
689 strcat (rname, dot);
690 return get_section (rname, SECTION_LINKONCE, decl);
692 /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo. */
693 else if (DECL_ONE_ONLY (decl)
694 && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
696 size_t len = strlen (name) + 1;
697 char *rname = (char *) alloca (len);
699 memcpy (rname, name, len);
700 rname[14] = 'r';
701 return get_section (rname, SECTION_LINKONCE, decl);
703 /* For .text.foo we want to use .rodata.foo. */
704 else if (flag_function_sections && flag_data_sections
705 && strncmp (name, ".text.", 6) == 0)
707 size_t len = strlen (name) + 1;
708 char *rname = (char *) alloca (len + 2);
710 memcpy (rname, ".rodata", 7);
711 memcpy (rname + 7, name + 5, len - 5);
712 return get_section (rname, 0, decl);
716 return readonly_data_section;
719 /* Return the read-only data section associated with function DECL
720 for targets where that section should be always the single
721 readonly data section. */
723 section *
724 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
726 return readonly_data_section;
729 /* Return the section to use for string merging. */
731 static section *
732 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
733 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
734 unsigned int flags ATTRIBUTE_UNUSED)
736 HOST_WIDE_INT len;
738 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
739 && TREE_CODE (decl) == STRING_CST
740 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
741 && align <= 256
742 && (len = int_size_in_bytes (TREE_TYPE (decl))) > 0
743 && TREE_STRING_LENGTH (decl) >= len)
745 enum machine_mode mode;
746 unsigned int modesize;
747 const char *str;
748 HOST_WIDE_INT i;
749 int j, unit;
750 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
751 char *name = (char *) alloca (strlen (prefix) + 30);
753 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
754 modesize = GET_MODE_BITSIZE (mode);
755 if (modesize >= 8 && modesize <= 256
756 && (modesize & (modesize - 1)) == 0)
758 if (align < modesize)
759 align = modesize;
761 str = TREE_STRING_POINTER (decl);
762 unit = GET_MODE_SIZE (mode);
764 /* Check for embedded NUL characters. */
765 for (i = 0; i < len; i += unit)
767 for (j = 0; j < unit; j++)
768 if (str[i + j] != '\0')
769 break;
770 if (j == unit)
771 break;
773 if (i == len - unit)
775 sprintf (name, "%s.str%d.%d", prefix,
776 modesize / 8, (int) (align / 8));
777 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
778 return get_section (name, flags, NULL);
783 return readonly_data_section;
786 /* Return the section to use for constant merging. */
788 section *
789 mergeable_constant_section (enum machine_mode mode ATTRIBUTE_UNUSED,
790 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
791 unsigned int flags ATTRIBUTE_UNUSED)
793 unsigned int modesize = GET_MODE_BITSIZE (mode);
795 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
796 && mode != VOIDmode
797 && mode != BLKmode
798 && modesize <= align
799 && align >= 8
800 && align <= 256
801 && (align & (align - 1)) == 0)
803 const char *prefix = targetm.asm_out.mergeable_rodata_prefix;
804 char *name = (char *) alloca (strlen (prefix) + 30);
806 sprintf (name, "%s.cst%d", prefix, (int) (align / 8));
807 flags |= (align / 8) | SECTION_MERGE;
808 return get_section (name, flags, NULL);
810 return readonly_data_section;
813 /* Given NAME, a putative register name, discard any customary prefixes. */
815 static const char *
816 strip_reg_name (const char *name)
818 #ifdef REGISTER_PREFIX
819 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
820 name += strlen (REGISTER_PREFIX);
821 #endif
822 if (name[0] == '%' || name[0] == '#')
823 name++;
824 return name;
827 /* The user has asked for a DECL to have a particular name. Set (or
828 change) it in such a way that we don't prefix an underscore to
829 it. */
830 void
831 set_user_assembler_name (tree decl, const char *name)
833 char *starred = (char *) alloca (strlen (name) + 2);
834 starred[0] = '*';
835 strcpy (starred + 1, name);
836 change_decl_assembler_name (decl, get_identifier (starred));
837 SET_DECL_RTL (decl, NULL_RTX);
840 /* Decode an `asm' spec for a declaration as a register name.
841 Return the register number, or -1 if nothing specified,
842 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
843 or -3 if ASMSPEC is `cc' and is not recognized,
844 or -4 if ASMSPEC is `memory' and is not recognized.
845 Accept an exact spelling or a decimal number.
846 Prefixes such as % are optional. */
849 decode_reg_name_and_count (const char *asmspec, int *pnregs)
851 /* Presume just one register is clobbered. */
852 *pnregs = 1;
854 if (asmspec != 0)
856 int i;
858 /* Get rid of confusing prefixes. */
859 asmspec = strip_reg_name (asmspec);
861 /* Allow a decimal number as a "register name". */
862 for (i = strlen (asmspec) - 1; i >= 0; i--)
863 if (! ISDIGIT (asmspec[i]))
864 break;
865 if (asmspec[0] != 0 && i < 0)
867 i = atoi (asmspec);
868 if (i < FIRST_PSEUDO_REGISTER && i >= 0)
869 return i;
870 else
871 return -2;
874 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
875 if (reg_names[i][0]
876 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
877 return i;
879 #ifdef OVERLAPPING_REGISTER_NAMES
881 static const struct
883 const char *const name;
884 const int number;
885 const int nregs;
886 } table[] = OVERLAPPING_REGISTER_NAMES;
888 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
889 if (table[i].name[0]
890 && ! strcmp (asmspec, table[i].name))
892 *pnregs = table[i].nregs;
893 return table[i].number;
896 #endif /* OVERLAPPING_REGISTER_NAMES */
898 #ifdef ADDITIONAL_REGISTER_NAMES
900 static const struct { const char *const name; const int number; } table[]
901 = ADDITIONAL_REGISTER_NAMES;
903 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
904 if (table[i].name[0]
905 && ! strcmp (asmspec, table[i].name))
906 return table[i].number;
908 #endif /* ADDITIONAL_REGISTER_NAMES */
910 if (!strcmp (asmspec, "memory"))
911 return -4;
913 if (!strcmp (asmspec, "cc"))
914 return -3;
916 return -2;
919 return -1;
923 decode_reg_name (const char *name)
925 int count;
926 return decode_reg_name_and_count (name, &count);
930 /* Return true if DECL's initializer is suitable for a BSS section. */
932 static bool
933 bss_initializer_p (const_tree decl)
935 return (DECL_INITIAL (decl) == NULL
936 || DECL_INITIAL (decl) == error_mark_node
937 || (flag_zero_initialized_in_bss
938 /* Leave constant zeroes in .rodata so they
939 can be shared. */
940 && !TREE_READONLY (decl)
941 && initializer_zerop (DECL_INITIAL (decl))));
944 /* Compute the alignment of variable specified by DECL.
945 DONT_OUTPUT_DATA is from assemble_variable. */
947 void
948 align_variable (tree decl, bool dont_output_data)
950 unsigned int align = DECL_ALIGN (decl);
952 /* In the case for initialing an array whose length isn't specified,
953 where we have not yet been able to do the layout,
954 figure out the proper alignment now. */
955 if (dont_output_data && DECL_SIZE (decl) == 0
956 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
957 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
959 /* Some object file formats have a maximum alignment which they support.
960 In particular, a.out format supports a maximum alignment of 4. */
961 if (align > MAX_OFILE_ALIGNMENT)
963 warning (0, "alignment of %q+D is greater than maximum object "
964 "file alignment. Using %d", decl,
965 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
966 align = MAX_OFILE_ALIGNMENT;
969 /* On some machines, it is good to increase alignment sometimes. */
970 if (! DECL_USER_ALIGN (decl))
972 #ifdef DATA_ALIGNMENT
973 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
974 /* Don't increase alignment too much for TLS variables - TLS space
975 is too precious. */
976 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
977 align = data_align;
978 #endif
979 #ifdef CONSTANT_ALIGNMENT
980 if (DECL_INITIAL (decl) != 0 && DECL_INITIAL (decl) != error_mark_node)
982 unsigned int const_align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl),
983 align);
984 /* Don't increase alignment too much for TLS variables - TLS space
985 is too precious. */
986 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
987 align = const_align;
989 #endif
992 /* Reset the alignment in case we have made it tighter, so we can benefit
993 from it in get_pointer_alignment. */
994 DECL_ALIGN (decl) = align;
997 /* Return the section into which the given VAR_DECL or CONST_DECL
998 should be placed. PREFER_NOSWITCH_P is true if a noswitch
999 section should be used wherever possible. */
1001 section *
1002 get_variable_section (tree decl, bool prefer_noswitch_p)
1004 addr_space_t as = ADDR_SPACE_GENERIC;
1005 int reloc;
1007 if (TREE_TYPE (decl) != error_mark_node)
1008 as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1010 if (DECL_COMMON (decl))
1012 /* If the decl has been given an explicit section name, or it resides
1013 in a non-generic address space, then it isn't common, and shouldn't
1014 be handled as such. */
1015 gcc_assert (DECL_SECTION_NAME (decl) == NULL
1016 && ADDR_SPACE_GENERIC_P (as));
1017 if (DECL_THREAD_LOCAL_P (decl))
1018 return tls_comm_section;
1019 else if (TREE_PUBLIC (decl) && bss_initializer_p (decl))
1020 return comm_section;
1023 if (DECL_INITIAL (decl) == error_mark_node)
1024 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1025 else if (DECL_INITIAL (decl))
1026 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1027 else
1028 reloc = 0;
1030 resolve_unique_section (decl, reloc, flag_data_sections);
1031 if (IN_NAMED_SECTION (decl))
1032 return get_named_section (decl, NULL, reloc);
1034 if (ADDR_SPACE_GENERIC_P (as)
1035 && !DECL_THREAD_LOCAL_P (decl)
1036 && !(prefer_noswitch_p && targetm.have_switchable_bss_sections)
1037 && bss_initializer_p (decl))
1039 if (!TREE_PUBLIC (decl))
1040 return lcomm_section;
1041 if (bss_noswitch_section)
1042 return bss_noswitch_section;
1045 return targetm.asm_out.select_section (decl, reloc, DECL_ALIGN (decl));
1048 /* Return the block into which object_block DECL should be placed. */
1050 static struct object_block *
1051 get_block_for_decl (tree decl)
1053 section *sect;
1055 if (TREE_CODE (decl) == VAR_DECL)
1057 /* The object must be defined in this translation unit. */
1058 if (DECL_EXTERNAL (decl))
1059 return NULL;
1061 /* There's no point using object blocks for something that is
1062 isolated by definition. */
1063 if (DECL_ONE_ONLY (decl))
1064 return NULL;
1067 /* We can only calculate block offsets if the decl has a known
1068 constant size. */
1069 if (DECL_SIZE_UNIT (decl) == NULL)
1070 return NULL;
1071 if (!host_integerp (DECL_SIZE_UNIT (decl), 1))
1072 return NULL;
1074 /* Find out which section should contain DECL. We cannot put it into
1075 an object block if it requires a standalone definition. */
1076 if (TREE_CODE (decl) == VAR_DECL)
1077 align_variable (decl, 0);
1078 sect = get_variable_section (decl, true);
1079 if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
1080 return NULL;
1082 return get_block_for_section (sect);
1085 /* Make sure block symbol SYMBOL is in block BLOCK. */
1087 static void
1088 change_symbol_block (rtx symbol, struct object_block *block)
1090 if (block != SYMBOL_REF_BLOCK (symbol))
1092 gcc_assert (SYMBOL_REF_BLOCK_OFFSET (symbol) < 0);
1093 SYMBOL_REF_BLOCK (symbol) = block;
1097 /* Return true if it is possible to put DECL in an object_block. */
1099 static bool
1100 use_blocks_for_decl_p (tree decl)
1102 /* Only data DECLs can be placed into object blocks. */
1103 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != CONST_DECL)
1104 return false;
1106 /* Detect decls created by dw2_force_const_mem. Such decls are
1107 special because DECL_INITIAL doesn't specify the decl's true value.
1108 dw2_output_indirect_constants will instead call assemble_variable
1109 with dont_output_data set to 1 and then print the contents itself. */
1110 if (DECL_INITIAL (decl) == decl)
1111 return false;
1113 /* If this decl is an alias, then we don't want to emit a
1114 definition. */
1115 if (lookup_attribute ("alias", DECL_ATTRIBUTES (decl)))
1116 return false;
1118 return true;
1121 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
1122 have static storage duration. In other words, it should not be an
1123 automatic variable, including PARM_DECLs.
1125 There is, however, one exception: this function handles variables
1126 explicitly placed in a particular register by the user.
1128 This is never called for PARM_DECL nodes. */
1130 void
1131 make_decl_rtl (tree decl)
1133 const char *name = 0;
1134 int reg_number;
1135 rtx x;
1137 /* Check that we are not being given an automatic variable. */
1138 gcc_assert (TREE_CODE (decl) != PARM_DECL
1139 && TREE_CODE (decl) != RESULT_DECL);
1141 /* A weak alias has TREE_PUBLIC set but not the other bits. */
1142 gcc_assert (TREE_CODE (decl) != VAR_DECL
1143 || TREE_STATIC (decl)
1144 || TREE_PUBLIC (decl)
1145 || DECL_EXTERNAL (decl)
1146 || DECL_REGISTER (decl));
1148 /* And that we were not given a type or a label. */
1149 gcc_assert (TREE_CODE (decl) != TYPE_DECL
1150 && TREE_CODE (decl) != LABEL_DECL);
1152 /* For a duplicate declaration, we can be called twice on the
1153 same DECL node. Don't discard the RTL already made. */
1154 if (DECL_RTL_SET_P (decl))
1156 /* If the old RTL had the wrong mode, fix the mode. */
1157 x = DECL_RTL (decl);
1158 if (GET_MODE (x) != DECL_MODE (decl))
1159 SET_DECL_RTL (decl, adjust_address_nv (x, DECL_MODE (decl), 0));
1161 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1162 return;
1164 /* ??? Another way to do this would be to maintain a hashed
1165 table of such critters. Instead of adding stuff to a DECL
1166 to give certain attributes to it, we could use an external
1167 hash map from DECL to set of attributes. */
1169 /* Let the target reassign the RTL if it wants.
1170 This is necessary, for example, when one machine specific
1171 decl attribute overrides another. */
1172 targetm.encode_section_info (decl, DECL_RTL (decl), false);
1174 /* If the symbol has a SYMBOL_REF_BLOCK field, update it based
1175 on the new decl information. */
1176 if (MEM_P (x)
1177 && GET_CODE (XEXP (x, 0)) == SYMBOL_REF
1178 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (x, 0)))
1179 change_symbol_block (XEXP (x, 0), get_block_for_decl (decl));
1181 /* Make this function static known to the mudflap runtime. */
1182 if (flag_mudflap && TREE_CODE (decl) == VAR_DECL)
1183 mudflap_enqueue_decl (decl);
1185 return;
1188 /* If this variable belongs to the global constant pool, retrieve the
1189 pre-computed RTL or recompute it in LTO mode. */
1190 if (TREE_CODE (decl) == VAR_DECL && DECL_IN_CONSTANT_POOL (decl))
1192 SET_DECL_RTL (decl, output_constant_def (DECL_INITIAL (decl), 1));
1193 return;
1196 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
1198 if (name[0] != '*' && TREE_CODE (decl) != FUNCTION_DECL
1199 && DECL_REGISTER (decl))
1201 error ("register name not specified for %q+D", decl);
1203 else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1205 const char *asmspec = name+1;
1206 enum machine_mode mode = DECL_MODE (decl);
1207 reg_number = decode_reg_name (asmspec);
1208 /* First detect errors in declaring global registers. */
1209 if (reg_number == -1)
1210 error ("register name not specified for %q+D", decl);
1211 else if (reg_number < 0)
1212 error ("invalid register name for %q+D", decl);
1213 else if (mode == BLKmode)
1214 error ("data type of %q+D isn%'t suitable for a register",
1215 decl);
1216 else if (!in_hard_reg_set_p (accessible_reg_set, mode, reg_number))
1217 error ("the register specified for %q+D cannot be accessed"
1218 " by the current target", decl);
1219 else if (!in_hard_reg_set_p (operand_reg_set, mode, reg_number))
1220 error ("the register specified for %q+D is not general enough"
1221 " to be used as a register variable", decl);
1222 else if (!HARD_REGNO_MODE_OK (reg_number, mode))
1223 error ("register specified for %q+D isn%'t suitable for data type",
1224 decl);
1225 /* Now handle properly declared static register variables. */
1226 else
1228 int nregs;
1230 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
1232 DECL_INITIAL (decl) = 0;
1233 error ("global register variable has initial value");
1235 if (TREE_THIS_VOLATILE (decl))
1236 warning (OPT_Wvolatile_register_var,
1237 "optimization may eliminate reads and/or "
1238 "writes to register variables");
1240 /* If the user specified one of the eliminables registers here,
1241 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
1242 confused with that register and be eliminated. This usage is
1243 somewhat suspect... */
1245 SET_DECL_RTL (decl, gen_rtx_raw_REG (mode, reg_number));
1246 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
1247 REG_USERVAR_P (DECL_RTL (decl)) = 1;
1249 if (TREE_STATIC (decl))
1251 /* Make this register global, so not usable for anything
1252 else. */
1253 #ifdef ASM_DECLARE_REGISTER_GLOBAL
1254 name = IDENTIFIER_POINTER (DECL_NAME (decl));
1255 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
1256 #endif
1257 nregs = hard_regno_nregs[reg_number][mode];
1258 while (nregs > 0)
1259 globalize_reg (decl, reg_number + --nregs);
1262 /* As a register variable, it has no section. */
1263 return;
1266 /* Now handle ordinary static variables and functions (in memory).
1267 Also handle vars declared register invalidly. */
1268 else if (name[0] == '*')
1270 #ifdef REGISTER_PREFIX
1271 if (strlen (REGISTER_PREFIX) != 0)
1273 reg_number = decode_reg_name (name);
1274 if (reg_number >= 0 || reg_number == -3)
1275 error ("register name given for non-register variable %q+D", decl);
1277 #endif
1280 /* Specifying a section attribute on a variable forces it into a
1281 non-.bss section, and thus it cannot be common. */
1282 /* FIXME: In general this code should not be necessary because
1283 visibility pass is doing the same work. But notice_global_symbol
1284 is called early and it needs to make DECL_RTL to get the name.
1285 we take care of recomputing the DECL_RTL after visibility is changed. */
1286 if (TREE_CODE (decl) == VAR_DECL
1287 && DECL_SECTION_NAME (decl) != NULL_TREE
1288 && DECL_INITIAL (decl) == NULL_TREE
1289 && DECL_COMMON (decl))
1290 DECL_COMMON (decl) = 0;
1292 /* Variables can't be both common and weak. */
1293 if (TREE_CODE (decl) == VAR_DECL && DECL_WEAK (decl))
1294 DECL_COMMON (decl) = 0;
1296 if (use_object_blocks_p () && use_blocks_for_decl_p (decl))
1297 x = create_block_symbol (name, get_block_for_decl (decl), -1);
1298 else
1300 enum machine_mode address_mode = Pmode;
1301 if (TREE_TYPE (decl) != error_mark_node)
1303 addr_space_t as = TYPE_ADDR_SPACE (TREE_TYPE (decl));
1304 address_mode = targetm.addr_space.address_mode (as);
1306 x = gen_rtx_SYMBOL_REF (address_mode, name);
1308 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
1309 SET_SYMBOL_REF_DECL (x, decl);
1311 x = gen_rtx_MEM (DECL_MODE (decl), x);
1312 if (TREE_CODE (decl) != FUNCTION_DECL)
1313 set_mem_attributes (x, decl, 1);
1314 SET_DECL_RTL (decl, x);
1316 /* Optionally set flags or add text to the name to record information
1317 such as that it is a function name.
1318 If the name is changed, the macro ASM_OUTPUT_LABELREF
1319 will have to know how to strip this information. */
1320 targetm.encode_section_info (decl, DECL_RTL (decl), true);
1322 /* Make this function static known to the mudflap runtime. */
1323 if (flag_mudflap && TREE_CODE (decl) == VAR_DECL)
1324 mudflap_enqueue_decl (decl);
1327 /* Like make_decl_rtl, but inhibit creation of new alias sets when
1328 calling make_decl_rtl. Also, reset DECL_RTL before returning the
1329 rtl. */
1332 make_decl_rtl_for_debug (tree decl)
1334 unsigned int save_aliasing_flag, save_mudflap_flag;
1335 rtx rtl;
1337 if (DECL_RTL_SET_P (decl))
1338 return DECL_RTL (decl);
1340 /* Kludge alert! Somewhere down the call chain, make_decl_rtl will
1341 call new_alias_set. If running with -fcompare-debug, sometimes
1342 we do not want to create alias sets that will throw the alias
1343 numbers off in the comparison dumps. So... clearing
1344 flag_strict_aliasing will keep new_alias_set() from creating a
1345 new set. It is undesirable to register decl with mudflap
1346 in this case as well. */
1347 save_aliasing_flag = flag_strict_aliasing;
1348 flag_strict_aliasing = 0;
1349 save_mudflap_flag = flag_mudflap;
1350 flag_mudflap = 0;
1352 rtl = DECL_RTL (decl);
1353 /* Reset DECL_RTL back, as various parts of the compiler expects
1354 DECL_RTL set meaning it is actually going to be output. */
1355 SET_DECL_RTL (decl, NULL);
1357 flag_strict_aliasing = save_aliasing_flag;
1358 flag_mudflap = save_mudflap_flag;
1360 return rtl;
1363 /* Output a string of literal assembler code
1364 for an `asm' keyword used between functions. */
1366 void
1367 assemble_asm (tree string)
1369 app_enable ();
1371 if (TREE_CODE (string) == ADDR_EXPR)
1372 string = TREE_OPERAND (string, 0);
1374 fprintf (asm_out_file, "\t%s\n", TREE_STRING_POINTER (string));
1377 /* Record an element in the table of global destructors. SYMBOL is
1378 a SYMBOL_REF of the function to be called; PRIORITY is a number
1379 between 0 and MAX_INIT_PRIORITY. */
1381 void
1382 default_stabs_asm_out_destructor (rtx symbol ATTRIBUTE_UNUSED,
1383 int priority ATTRIBUTE_UNUSED)
1385 #if defined DBX_DEBUGGING_INFO || defined XCOFF_DEBUGGING_INFO
1386 /* Tell GNU LD that this is part of the static destructor set.
1387 This will work for any system that uses stabs, most usefully
1388 aout systems. */
1389 dbxout_begin_simple_stabs ("___DTOR_LIST__", 22 /* N_SETT */);
1390 dbxout_stab_value_label (XSTR (symbol, 0));
1391 #else
1392 sorry ("global destructors not supported on this target");
1393 #endif
1396 /* Write the address of the entity given by SYMBOL to SEC. */
1397 void
1398 assemble_addr_to_section (rtx symbol, section *sec)
1400 switch_to_section (sec);
1401 assemble_align (POINTER_SIZE);
1402 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1405 /* Return the numbered .ctors.N (if CONSTRUCTOR_P) or .dtors.N (if
1406 not) section for PRIORITY. */
1407 section *
1408 get_cdtor_priority_section (int priority, bool constructor_p)
1410 char buf[16];
1412 /* ??? This only works reliably with the GNU linker. */
1413 sprintf (buf, "%s.%.5u",
1414 constructor_p ? ".ctors" : ".dtors",
1415 /* Invert the numbering so the linker puts us in the proper
1416 order; constructors are run from right to left, and the
1417 linker sorts in increasing order. */
1418 MAX_INIT_PRIORITY - priority);
1419 return get_section (buf, SECTION_WRITE, NULL);
1422 void
1423 default_named_section_asm_out_destructor (rtx symbol, int priority)
1425 section *sec;
1427 if (priority != DEFAULT_INIT_PRIORITY)
1428 sec = get_cdtor_priority_section (priority,
1429 /*constructor_p=*/false);
1430 else
1431 sec = get_section (".dtors", SECTION_WRITE, NULL);
1433 assemble_addr_to_section (symbol, sec);
1436 #ifdef DTORS_SECTION_ASM_OP
1437 void
1438 default_dtor_section_asm_out_destructor (rtx symbol,
1439 int priority ATTRIBUTE_UNUSED)
1441 assemble_addr_to_section (symbol, dtors_section);
1443 #endif
1445 /* Likewise for global constructors. */
1447 void
1448 default_stabs_asm_out_constructor (rtx symbol ATTRIBUTE_UNUSED,
1449 int priority ATTRIBUTE_UNUSED)
1451 #if defined DBX_DEBUGGING_INFO || defined XCOFF_DEBUGGING_INFO
1452 /* Tell GNU LD that this is part of the static destructor set.
1453 This will work for any system that uses stabs, most usefully
1454 aout systems. */
1455 dbxout_begin_simple_stabs ("___CTOR_LIST__", 22 /* N_SETT */);
1456 dbxout_stab_value_label (XSTR (symbol, 0));
1457 #else
1458 sorry ("global constructors not supported on this target");
1459 #endif
1462 void
1463 default_named_section_asm_out_constructor (rtx symbol, int priority)
1465 section *sec;
1467 if (priority != DEFAULT_INIT_PRIORITY)
1468 sec = get_cdtor_priority_section (priority,
1469 /*constructor_p=*/true);
1470 else
1471 sec = get_section (".ctors", SECTION_WRITE, NULL);
1473 assemble_addr_to_section (symbol, sec);
1476 #ifdef CTORS_SECTION_ASM_OP
1477 void
1478 default_ctor_section_asm_out_constructor (rtx symbol,
1479 int priority ATTRIBUTE_UNUSED)
1481 assemble_addr_to_section (symbol, ctors_section);
1483 #endif
1485 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1486 a nonzero value if the constant pool should be output before the
1487 start of the function, or a zero value if the pool should output
1488 after the end of the function. The default is to put it before the
1489 start. */
1491 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1492 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1493 #endif
1495 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1496 to be output to assembler.
1497 Set first_global_object_name and weak_global_object_name as appropriate. */
1499 void
1500 notice_global_symbol (tree decl)
1502 const char **type = &first_global_object_name;
1504 if (first_global_object_name
1505 || !TREE_PUBLIC (decl)
1506 || DECL_EXTERNAL (decl)
1507 || !DECL_NAME (decl)
1508 || (TREE_CODE (decl) != FUNCTION_DECL
1509 && (TREE_CODE (decl) != VAR_DECL
1510 || (DECL_COMMON (decl)
1511 && (DECL_INITIAL (decl) == 0
1512 || DECL_INITIAL (decl) == error_mark_node))))
1513 || !MEM_P (DECL_RTL (decl)))
1514 return;
1516 /* We win when global object is found, but it is useful to know about weak
1517 symbol as well so we can produce nicer unique names. */
1518 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl) || flag_shlib)
1519 type = &weak_global_object_name;
1521 if (!*type)
1523 const char *p;
1524 const char *name;
1525 rtx decl_rtl = DECL_RTL (decl);
1527 p = targetm.strip_name_encoding (XSTR (XEXP (decl_rtl, 0), 0));
1528 name = ggc_strdup (p);
1530 *type = name;
1534 /* If not using flag_reorder_blocks_and_partition, decide early whether the
1535 current function goes into the cold section, so that targets can use
1536 current_function_section during RTL expansion. DECL describes the
1537 function. */
1539 void
1540 decide_function_section (tree decl)
1542 first_function_block_is_cold = false;
1544 if (flag_reorder_blocks_and_partition)
1545 /* We will decide in assemble_start_function. */
1546 return;
1548 if (DECL_SECTION_NAME (decl))
1550 struct cgraph_node *node = cgraph_get_node (current_function_decl);
1551 /* Calls to function_section rely on first_function_block_is_cold
1552 being accurate. */
1553 first_function_block_is_cold = (node
1554 && node->frequency
1555 == NODE_FREQUENCY_UNLIKELY_EXECUTED);
1558 in_cold_section_p = first_function_block_is_cold;
1561 /* Output assembler code for the constant pool of a function and associated
1562 with defining the name of the function. DECL describes the function.
1563 NAME is the function's name. For the constant pool, we use the current
1564 constant pool data. */
1566 void
1567 assemble_start_function (tree decl, const char *fnname)
1569 int align;
1570 char tmp_label[100];
1571 bool hot_label_written = false;
1573 if (flag_reorder_blocks_and_partition)
1575 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTB", const_labelno);
1576 crtl->subsections.hot_section_label = ggc_strdup (tmp_label);
1577 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDB", const_labelno);
1578 crtl->subsections.cold_section_label = ggc_strdup (tmp_label);
1579 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTE", const_labelno);
1580 crtl->subsections.hot_section_end_label = ggc_strdup (tmp_label);
1581 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDE", const_labelno);
1582 crtl->subsections.cold_section_end_label = ggc_strdup (tmp_label);
1583 const_labelno++;
1585 else
1587 crtl->subsections.hot_section_label = NULL;
1588 crtl->subsections.cold_section_label = NULL;
1589 crtl->subsections.hot_section_end_label = NULL;
1590 crtl->subsections.cold_section_end_label = NULL;
1593 /* The following code does not need preprocessing in the assembler. */
1595 app_disable ();
1597 if (CONSTANT_POOL_BEFORE_FUNCTION)
1598 output_constant_pool (fnname, decl);
1600 /* Make sure the not and cold text (code) sections are properly
1601 aligned. This is necessary here in the case where the function
1602 has both hot and cold sections, because we don't want to re-set
1603 the alignment when the section switch happens mid-function. */
1605 if (flag_reorder_blocks_and_partition)
1607 first_function_block_is_cold = false;
1609 switch_to_section (unlikely_text_section ());
1610 assemble_align (DECL_ALIGN (decl));
1611 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_label);
1613 /* When the function starts with a cold section, we need to explicitly
1614 align the hot section and write out the hot section label.
1615 But if the current function is a thunk, we do not have a CFG. */
1616 if (!cfun->is_thunk
1617 && BB_PARTITION (ENTRY_BLOCK_PTR->next_bb) == BB_COLD_PARTITION)
1619 switch_to_section (text_section);
1620 assemble_align (DECL_ALIGN (decl));
1621 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1622 hot_label_written = true;
1623 first_function_block_is_cold = true;
1625 in_cold_section_p = first_function_block_is_cold;
1629 /* Switch to the correct text section for the start of the function. */
1631 switch_to_section (function_section (decl));
1632 if (flag_reorder_blocks_and_partition
1633 && !hot_label_written)
1634 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1636 /* Tell assembler to move to target machine's alignment for functions. */
1637 align = floor_log2 (DECL_ALIGN (decl) / BITS_PER_UNIT);
1638 if (align > 0)
1640 ASM_OUTPUT_ALIGN (asm_out_file, align);
1643 /* Handle a user-specified function alignment.
1644 Note that we still need to align to DECL_ALIGN, as above,
1645 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1646 if (! DECL_USER_ALIGN (decl)
1647 && align_functions_log > align
1648 && optimize_function_for_speed_p (cfun))
1650 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1651 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1652 align_functions_log, align_functions - 1);
1653 #else
1654 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1655 #endif
1658 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1659 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1660 #endif
1662 if (!DECL_IGNORED_P (decl))
1663 (*debug_hooks->begin_function) (decl);
1665 /* Make function name accessible from other files, if appropriate. */
1667 if (TREE_PUBLIC (decl))
1669 notice_global_symbol (decl);
1671 globalize_decl (decl);
1673 maybe_assemble_visibility (decl);
1676 if (DECL_PRESERVE_P (decl))
1677 targetm.asm_out.mark_decl_preserved (fnname);
1679 /* Do any machine/system dependent processing of the function name. */
1680 #ifdef ASM_DECLARE_FUNCTION_NAME
1681 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1682 #else
1683 /* Standard thing is just output label for the function. */
1684 ASM_OUTPUT_FUNCTION_LABEL (asm_out_file, fnname, current_function_decl);
1685 #endif /* ASM_DECLARE_FUNCTION_NAME */
1687 if (lookup_attribute ("no_split_stack", DECL_ATTRIBUTES (decl)))
1688 saw_no_split_stack = true;
1691 /* Output assembler code associated with defining the size of the
1692 function. DECL describes the function. NAME is the function's name. */
1694 void
1695 assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED)
1697 #ifdef ASM_DECLARE_FUNCTION_SIZE
1698 /* We could have switched section in the middle of the function. */
1699 if (flag_reorder_blocks_and_partition)
1700 switch_to_section (function_section (decl));
1701 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1702 #endif
1703 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1705 output_constant_pool (fnname, decl);
1706 switch_to_section (function_section (decl)); /* need to switch back */
1708 /* Output labels for end of hot/cold text sections (to be used by
1709 debug info.) */
1710 if (flag_reorder_blocks_and_partition)
1712 section *save_text_section;
1714 save_text_section = in_section;
1715 switch_to_section (unlikely_text_section ());
1716 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label);
1717 if (first_function_block_is_cold)
1718 switch_to_section (text_section);
1719 else
1720 switch_to_section (function_section (decl));
1721 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label);
1722 switch_to_section (save_text_section);
1726 /* Assemble code to leave SIZE bytes of zeros. */
1728 void
1729 assemble_zeros (unsigned HOST_WIDE_INT size)
1731 /* Do no output if -fsyntax-only. */
1732 if (flag_syntax_only)
1733 return;
1735 #ifdef ASM_NO_SKIP_IN_TEXT
1736 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1737 so we must output 0s explicitly in the text section. */
1738 if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0)
1740 unsigned HOST_WIDE_INT i;
1741 for (i = 0; i < size; i++)
1742 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1744 else
1745 #endif
1746 if (size > 0)
1747 ASM_OUTPUT_SKIP (asm_out_file, size);
1750 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1752 void
1753 assemble_align (int align)
1755 if (align > BITS_PER_UNIT)
1757 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1761 /* Assemble a string constant with the specified C string as contents. */
1763 void
1764 assemble_string (const char *p, int size)
1766 int pos = 0;
1767 int maximum = 2000;
1769 /* If the string is very long, split it up. */
1771 while (pos < size)
1773 int thissize = size - pos;
1774 if (thissize > maximum)
1775 thissize = maximum;
1777 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1779 pos += thissize;
1780 p += thissize;
1785 /* A noswitch_section_callback for lcomm_section. */
1787 static bool
1788 emit_local (tree decl ATTRIBUTE_UNUSED,
1789 const char *name ATTRIBUTE_UNUSED,
1790 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1791 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1793 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1794 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name,
1795 size, DECL_ALIGN (decl));
1796 return true;
1797 #elif defined ASM_OUTPUT_ALIGNED_LOCAL
1798 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, DECL_ALIGN (decl));
1799 return true;
1800 #else
1801 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1802 return false;
1803 #endif
1806 /* A noswitch_section_callback for bss_noswitch_section. */
1808 #if defined ASM_OUTPUT_ALIGNED_BSS
1809 static bool
1810 emit_bss (tree decl ATTRIBUTE_UNUSED,
1811 const char *name ATTRIBUTE_UNUSED,
1812 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1813 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1815 #if defined ASM_OUTPUT_ALIGNED_BSS
1816 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size, DECL_ALIGN (decl));
1817 return true;
1818 #endif
1820 #endif
1822 /* A noswitch_section_callback for comm_section. */
1824 static bool
1825 emit_common (tree decl ATTRIBUTE_UNUSED,
1826 const char *name ATTRIBUTE_UNUSED,
1827 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1828 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1830 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1831 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name,
1832 size, DECL_ALIGN (decl));
1833 return true;
1834 #elif defined ASM_OUTPUT_ALIGNED_COMMON
1835 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size, DECL_ALIGN (decl));
1836 return true;
1837 #else
1838 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
1839 return false;
1840 #endif
1843 /* A noswitch_section_callback for tls_comm_section. */
1845 static bool
1846 emit_tls_common (tree decl ATTRIBUTE_UNUSED,
1847 const char *name ATTRIBUTE_UNUSED,
1848 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1849 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1851 #ifdef ASM_OUTPUT_TLS_COMMON
1852 ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size);
1853 return true;
1854 #else
1855 sorry ("thread-local COMMON data not implemented");
1856 return true;
1857 #endif
1860 /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT.
1861 NAME is the name of DECL's SYMBOL_REF. */
1863 static void
1864 assemble_noswitch_variable (tree decl, const char *name, section *sect)
1866 unsigned HOST_WIDE_INT size, rounded;
1868 size = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
1869 rounded = size;
1871 /* Don't allocate zero bytes of common,
1872 since that means "undefined external" in the linker. */
1873 if (size == 0)
1874 rounded = 1;
1876 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1877 so that each uninitialized object starts on such a boundary. */
1878 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
1879 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1880 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1882 if (!sect->noswitch.callback (decl, name, size, rounded)
1883 && (unsigned HOST_WIDE_INT) DECL_ALIGN_UNIT (decl) > rounded)
1884 warning (0, "requested alignment for %q+D is greater than "
1885 "implemented alignment of %wu", decl, rounded);
1888 /* A subroutine of assemble_variable. Output the label and contents of
1889 DECL, whose address is a SYMBOL_REF with name NAME. DONT_OUTPUT_DATA
1890 is as for assemble_variable. */
1892 static void
1893 assemble_variable_contents (tree decl, const char *name,
1894 bool dont_output_data)
1896 /* Do any machine/system dependent processing of the object. */
1897 #ifdef ASM_DECLARE_OBJECT_NAME
1898 last_assemble_variable_decl = decl;
1899 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
1900 #else
1901 /* Standard thing is just output label for the object. */
1902 ASM_OUTPUT_LABEL (asm_out_file, name);
1903 #endif /* ASM_DECLARE_OBJECT_NAME */
1905 if (!dont_output_data)
1907 if (DECL_INITIAL (decl)
1908 && DECL_INITIAL (decl) != error_mark_node
1909 && !initializer_zerop (DECL_INITIAL (decl)))
1910 /* Output the actual data. */
1911 output_constant (DECL_INITIAL (decl),
1912 tree_low_cst (DECL_SIZE_UNIT (decl), 1),
1913 DECL_ALIGN (decl));
1914 else
1915 /* Leave space for it. */
1916 assemble_zeros (tree_low_cst (DECL_SIZE_UNIT (decl), 1));
1920 /* Assemble everything that is needed for a variable or function declaration.
1921 Not used for automatic variables, and not used for function definitions.
1922 Should not be called for variables of incomplete structure type.
1924 TOP_LEVEL is nonzero if this variable has file scope.
1925 AT_END is nonzero if this is the special handling, at end of compilation,
1926 to define things that have had only tentative definitions.
1927 DONT_OUTPUT_DATA if nonzero means don't actually output the
1928 initial value (that will be done by the caller). */
1930 void
1931 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
1932 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
1934 const char *name;
1935 rtx decl_rtl, symbol;
1936 section *sect;
1938 /* This function is supposed to handle VARIABLES. Ensure we have one. */
1939 gcc_assert (TREE_CODE (decl) == VAR_DECL);
1941 /* Emulated TLS had better not get this far. */
1942 gcc_checking_assert (targetm.have_tls || !DECL_THREAD_LOCAL_P (decl));
1944 last_assemble_variable_decl = 0;
1946 /* Normally no need to say anything here for external references,
1947 since assemble_external is called by the language-specific code
1948 when a declaration is first seen. */
1950 if (DECL_EXTERNAL (decl))
1951 return;
1953 /* Do nothing for global register variables. */
1954 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
1956 TREE_ASM_WRITTEN (decl) = 1;
1957 return;
1960 /* If type was incomplete when the variable was declared,
1961 see if it is complete now. */
1963 if (DECL_SIZE (decl) == 0)
1964 layout_decl (decl, 0);
1966 /* Still incomplete => don't allocate it; treat the tentative defn
1967 (which is what it must have been) as an `extern' reference. */
1969 if (!dont_output_data && DECL_SIZE (decl) == 0)
1971 error ("storage size of %q+D isn%'t known", decl);
1972 TREE_ASM_WRITTEN (decl) = 1;
1973 return;
1976 /* The first declaration of a variable that comes through this function
1977 decides whether it is global (in C, has external linkage)
1978 or local (in C, has internal linkage). So do nothing more
1979 if this function has already run. */
1981 if (TREE_ASM_WRITTEN (decl))
1982 return;
1984 /* Make sure targetm.encode_section_info is invoked before we set
1985 ASM_WRITTEN. */
1986 decl_rtl = DECL_RTL (decl);
1988 TREE_ASM_WRITTEN (decl) = 1;
1990 /* Do no output if -fsyntax-only. */
1991 if (flag_syntax_only)
1992 return;
1994 if (! dont_output_data
1995 && ! host_integerp (DECL_SIZE_UNIT (decl), 1))
1997 error ("size of variable %q+D is too large", decl);
1998 return;
2001 gcc_assert (MEM_P (decl_rtl));
2002 gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF);
2003 symbol = XEXP (decl_rtl, 0);
2005 /* If this symbol belongs to the tree constant pool, output the constant
2006 if it hasn't already been written. */
2007 if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
2009 tree decl = SYMBOL_REF_DECL (symbol);
2010 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
2011 output_constant_def_contents (symbol);
2012 return;
2015 app_disable ();
2017 name = XSTR (symbol, 0);
2018 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
2019 notice_global_symbol (decl);
2021 /* Compute the alignment of this data. */
2023 align_variable (decl, dont_output_data);
2024 set_mem_align (decl_rtl, DECL_ALIGN (decl));
2026 if (TREE_PUBLIC (decl))
2027 maybe_assemble_visibility (decl);
2029 if (DECL_PRESERVE_P (decl))
2030 targetm.asm_out.mark_decl_preserved (name);
2032 /* First make the assembler name(s) global if appropriate. */
2033 sect = get_variable_section (decl, false);
2034 if (TREE_PUBLIC (decl)
2035 && (sect->common.flags & SECTION_COMMON) == 0)
2036 globalize_decl (decl);
2038 /* Output any data that we will need to use the address of. */
2039 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
2040 output_addressed_constants (DECL_INITIAL (decl));
2042 /* dbxout.c needs to know this. */
2043 if (sect && (sect->common.flags & SECTION_CODE) != 0)
2044 DECL_IN_TEXT_SECTION (decl) = 1;
2046 /* If the decl is part of an object_block, make sure that the decl
2047 has been positioned within its block, but do not write out its
2048 definition yet. output_object_blocks will do that later. */
2049 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
2051 gcc_assert (!dont_output_data);
2052 place_block_symbol (symbol);
2054 else if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
2055 assemble_noswitch_variable (decl, name, sect);
2056 else
2058 switch_to_section (sect);
2059 if (DECL_ALIGN (decl) > BITS_PER_UNIT)
2060 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (DECL_ALIGN_UNIT (decl)));
2061 assemble_variable_contents (decl, name, dont_output_data);
2065 /* Return 1 if type TYPE contains any pointers. */
2067 static int
2068 contains_pointers_p (tree type)
2070 switch (TREE_CODE (type))
2072 case POINTER_TYPE:
2073 case REFERENCE_TYPE:
2074 /* I'm not sure whether OFFSET_TYPE needs this treatment,
2075 so I'll play safe and return 1. */
2076 case OFFSET_TYPE:
2077 return 1;
2079 case RECORD_TYPE:
2080 case UNION_TYPE:
2081 case QUAL_UNION_TYPE:
2083 tree fields;
2084 /* For a type that has fields, see if the fields have pointers. */
2085 for (fields = TYPE_FIELDS (type); fields; fields = DECL_CHAIN (fields))
2086 if (TREE_CODE (fields) == FIELD_DECL
2087 && contains_pointers_p (TREE_TYPE (fields)))
2088 return 1;
2089 return 0;
2092 case ARRAY_TYPE:
2093 /* An array type contains pointers if its element type does. */
2094 return contains_pointers_p (TREE_TYPE (type));
2096 default:
2097 return 0;
2101 /* We delay assemble_external processing until
2102 the compilation unit is finalized. This is the best we can do for
2103 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2104 it all the way to final. See PR 17982 for further discussion. */
2105 static GTY(()) tree pending_assemble_externals;
2107 #ifdef ASM_OUTPUT_EXTERNAL
2108 /* True if DECL is a function decl for which no out-of-line copy exists.
2109 It is assumed that DECL's assembler name has been set. */
2111 static bool
2112 incorporeal_function_p (tree decl)
2114 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
2116 const char *name;
2118 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2119 && (DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA
2120 || DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA_WITH_ALIGN))
2121 return true;
2123 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2124 /* Atomic or sync builtins which have survived this far will be
2125 resolved externally and therefore are not incorporeal. */
2126 if (strncmp (name, "__builtin_", 10) == 0)
2127 return true;
2129 return false;
2132 /* Actually do the tests to determine if this is necessary, and invoke
2133 ASM_OUTPUT_EXTERNAL. */
2134 static void
2135 assemble_external_real (tree decl)
2137 rtx rtl = DECL_RTL (decl);
2139 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2140 && !SYMBOL_REF_USED (XEXP (rtl, 0))
2141 && !incorporeal_function_p (decl))
2143 /* Some systems do require some output. */
2144 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2145 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2148 #endif
2150 void
2151 process_pending_assemble_externals (void)
2153 #ifdef ASM_OUTPUT_EXTERNAL
2154 tree list;
2155 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2156 assemble_external_real (TREE_VALUE (list));
2158 pending_assemble_externals = 0;
2159 #endif
2162 /* This TREE_LIST contains any weak symbol declarations waiting
2163 to be emitted. */
2164 static GTY(()) tree weak_decls;
2166 /* Output something to declare an external symbol to the assembler,
2167 and qualifiers such as weakness. (Most assemblers don't need
2168 extern declaration, so we normally output nothing.) Do nothing if
2169 DECL is not external. */
2171 void
2172 assemble_external (tree decl ATTRIBUTE_UNUSED)
2174 /* Make sure that the ASM_OUT_FILE is open.
2175 If it's not, we should not be calling this function. */
2176 gcc_assert (asm_out_file);
2178 /* In a perfect world, the following condition would be true.
2179 Sadly, the Java and Go front ends emit assembly *from the front end*,
2180 bypassing the call graph. See PR52739. Fix before GCC 4.8. */
2181 #if 0
2182 /* This function should only be called if we are expanding, or have
2183 expanded, to RTL.
2184 Ideally, only final.c would be calling this function, but it is
2185 not clear whether that would break things somehow. See PR 17982
2186 for further discussion. */
2187 gcc_assert (cgraph_state == CGRAPH_STATE_EXPANSION
2188 || cgraph_state == CGRAPH_STATE_FINISHED);
2189 #endif
2191 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2192 return;
2194 /* We want to output annotation for weak and external symbols at
2195 very last to check if they are references or not. */
2197 if (TARGET_SUPPORTS_WEAK
2198 && DECL_WEAK (decl)
2199 /* TREE_STATIC is a weird and abused creature which is not
2200 generally the right test for whether an entity has been
2201 locally emitted, inlined or otherwise not-really-extern, but
2202 for declarations that can be weak, it happens to be
2203 match. */
2204 && !TREE_STATIC (decl)
2205 && lookup_attribute ("weak", DECL_ATTRIBUTES (decl))
2206 && value_member (decl, weak_decls) == NULL_TREE)
2207 weak_decls = tree_cons (NULL, decl, weak_decls);
2209 #ifdef ASM_OUTPUT_EXTERNAL
2210 if (value_member (decl, pending_assemble_externals) == NULL_TREE)
2211 pending_assemble_externals = tree_cons (NULL, decl,
2212 pending_assemble_externals);
2213 #endif
2216 /* Similar, for calling a library function FUN. */
2218 void
2219 assemble_external_libcall (rtx fun)
2221 /* Declare library function name external when first used, if nec. */
2222 if (! SYMBOL_REF_USED (fun))
2224 SYMBOL_REF_USED (fun) = 1;
2225 targetm.asm_out.external_libcall (fun);
2229 /* Assemble a label named NAME. */
2231 void
2232 assemble_label (FILE *file, const char *name)
2234 ASM_OUTPUT_LABEL (file, name);
2237 /* Set the symbol_referenced flag for ID. */
2238 void
2239 mark_referenced (tree id)
2241 TREE_SYMBOL_REFERENCED (id) = 1;
2244 /* Set the symbol_referenced flag for DECL and notify callgraph. */
2245 void
2246 mark_decl_referenced (tree decl)
2248 if (TREE_CODE (decl) == FUNCTION_DECL)
2250 /* Extern inline functions don't become needed when referenced.
2251 If we know a method will be emitted in other TU and no new
2252 functions can be marked reachable, just use the external
2253 definition. */
2254 struct cgraph_node *node = cgraph_get_create_node (decl);
2255 if (!DECL_EXTERNAL (decl)
2256 && !node->local.finalized)
2257 cgraph_mark_force_output_node (node);
2259 else if (TREE_CODE (decl) == VAR_DECL)
2261 struct varpool_node *node = varpool_node (decl);
2262 /* C++ frontend use mark_decl_references to force COMDAT variables
2263 to be output that might appear dead otherwise. */
2264 node->symbol.force_output = true;
2266 /* else do nothing - we can get various sorts of CST nodes here,
2267 which do not need to be marked. */
2271 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS
2272 until we find an identifier that is not itself a transparent alias.
2273 Modify the alias passed to it by reference (and all aliases on the
2274 way to the ultimate target), such that they do not have to be
2275 followed again, and return the ultimate target of the alias
2276 chain. */
2278 static inline tree
2279 ultimate_transparent_alias_target (tree *alias)
2281 tree target = *alias;
2283 if (IDENTIFIER_TRANSPARENT_ALIAS (target))
2285 gcc_assert (TREE_CHAIN (target));
2286 target = ultimate_transparent_alias_target (&TREE_CHAIN (target));
2287 gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target)
2288 && ! TREE_CHAIN (target));
2289 *alias = target;
2292 return target;
2295 /* Output to FILE (an assembly file) a reference to NAME. If NAME
2296 starts with a *, the rest of NAME is output verbatim. Otherwise
2297 NAME is transformed in a target-specific way (usually by the
2298 addition of an underscore). */
2300 void
2301 assemble_name_raw (FILE *file, const char *name)
2303 if (name[0] == '*')
2304 fputs (&name[1], file);
2305 else
2306 ASM_OUTPUT_LABELREF (file, name);
2309 /* Like assemble_name_raw, but should be used when NAME might refer to
2310 an entity that is also represented as a tree (like a function or
2311 variable). If NAME does refer to such an entity, that entity will
2312 be marked as referenced. */
2314 void
2315 assemble_name (FILE *file, const char *name)
2317 const char *real_name;
2318 tree id;
2320 real_name = targetm.strip_name_encoding (name);
2322 id = maybe_get_identifier (real_name);
2323 if (id)
2325 tree id_orig = id;
2327 mark_referenced (id);
2328 ultimate_transparent_alias_target (&id);
2329 if (id != id_orig)
2330 name = IDENTIFIER_POINTER (id);
2331 gcc_assert (! TREE_CHAIN (id));
2334 assemble_name_raw (file, name);
2337 /* Allocate SIZE bytes writable static space with a gensym name
2338 and return an RTX to refer to its address. */
2341 assemble_static_space (unsigned HOST_WIDE_INT size)
2343 char name[12];
2344 const char *namestring;
2345 rtx x;
2347 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2348 ++const_labelno;
2349 namestring = ggc_strdup (name);
2351 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2352 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2354 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2355 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2356 BIGGEST_ALIGNMENT);
2357 #else
2358 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2359 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2360 #else
2362 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2363 so that each uninitialized object starts on such a boundary. */
2364 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2365 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2366 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2367 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2368 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2369 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2371 #endif
2372 #endif
2373 return x;
2376 /* Assemble the static constant template for function entry trampolines.
2377 This is done at most once per compilation.
2378 Returns an RTX for the address of the template. */
2380 static GTY(()) rtx initial_trampoline;
2383 assemble_trampoline_template (void)
2385 char label[256];
2386 const char *name;
2387 int align;
2388 rtx symbol;
2390 gcc_assert (targetm.asm_out.trampoline_template != NULL);
2392 if (initial_trampoline)
2393 return initial_trampoline;
2395 /* By default, put trampoline templates in read-only data section. */
2397 #ifdef TRAMPOLINE_SECTION
2398 switch_to_section (TRAMPOLINE_SECTION);
2399 #else
2400 switch_to_section (readonly_data_section);
2401 #endif
2403 /* Write the assembler code to define one. */
2404 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2405 if (align > 0)
2406 ASM_OUTPUT_ALIGN (asm_out_file, align);
2408 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2409 targetm.asm_out.trampoline_template (asm_out_file);
2411 /* Record the rtl to refer to it. */
2412 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2413 name = ggc_strdup (label);
2414 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2415 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2417 initial_trampoline = gen_const_mem (BLKmode, symbol);
2418 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2419 set_mem_size (initial_trampoline, TRAMPOLINE_SIZE);
2421 return initial_trampoline;
2424 /* A and B are either alignments or offsets. Return the minimum alignment
2425 that may be assumed after adding the two together. */
2427 static inline unsigned
2428 min_align (unsigned int a, unsigned int b)
2430 return (a | b) & -(a | b);
2433 /* Return the assembler directive for creating a given kind of integer
2434 object. SIZE is the number of bytes in the object and ALIGNED_P
2435 indicates whether it is known to be aligned. Return NULL if the
2436 assembly dialect has no such directive.
2438 The returned string should be printed at the start of a new line and
2439 be followed immediately by the object's initial value. */
2441 const char *
2442 integer_asm_op (int size, int aligned_p)
2444 struct asm_int_op *ops;
2446 if (aligned_p)
2447 ops = &targetm.asm_out.aligned_op;
2448 else
2449 ops = &targetm.asm_out.unaligned_op;
2451 switch (size)
2453 case 1:
2454 return targetm.asm_out.byte_op;
2455 case 2:
2456 return ops->hi;
2457 case 4:
2458 return ops->si;
2459 case 8:
2460 return ops->di;
2461 case 16:
2462 return ops->ti;
2463 default:
2464 return NULL;
2468 /* Use directive OP to assemble an integer object X. Print OP at the
2469 start of the line, followed immediately by the value of X. */
2471 void
2472 assemble_integer_with_op (const char *op, rtx x)
2474 fputs (op, asm_out_file);
2475 output_addr_const (asm_out_file, x);
2476 fputc ('\n', asm_out_file);
2479 /* The default implementation of the asm_out.integer target hook. */
2481 bool
2482 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2483 unsigned int size ATTRIBUTE_UNUSED,
2484 int aligned_p ATTRIBUTE_UNUSED)
2486 const char *op = integer_asm_op (size, aligned_p);
2487 /* Avoid GAS bugs for large values. Specifically negative values whose
2488 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2489 if (size > UNITS_PER_WORD && size > POINTER_SIZE / BITS_PER_UNIT)
2490 return false;
2491 return op && (assemble_integer_with_op (op, x), true);
2494 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2495 the alignment of the integer in bits. Return 1 if we were able to output
2496 the constant, otherwise 0. We must be able to output the constant,
2497 if FORCE is nonzero. */
2499 bool
2500 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2502 int aligned_p;
2504 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2506 /* See if the target hook can handle this kind of object. */
2507 if (targetm.asm_out.integer (x, size, aligned_p))
2508 return true;
2510 /* If the object is a multi-byte one, try splitting it up. Split
2511 it into words it if is multi-word, otherwise split it into bytes. */
2512 if (size > 1)
2514 enum machine_mode omode, imode;
2515 unsigned int subalign;
2516 unsigned int subsize, i;
2517 enum mode_class mclass;
2519 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2520 subalign = MIN (align, subsize * BITS_PER_UNIT);
2521 if (GET_CODE (x) == CONST_FIXED)
2522 mclass = GET_MODE_CLASS (GET_MODE (x));
2523 else
2524 mclass = MODE_INT;
2526 omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0);
2527 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0);
2529 for (i = 0; i < size; i += subsize)
2531 rtx partial = simplify_subreg (omode, x, imode, i);
2532 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2533 break;
2535 if (i == size)
2536 return true;
2538 /* If we've printed some of it, but not all of it, there's no going
2539 back now. */
2540 gcc_assert (!i);
2543 gcc_assert (!force);
2545 return false;
2548 void
2549 assemble_real (REAL_VALUE_TYPE d, enum machine_mode mode, unsigned int align)
2551 long data[4] = {0, 0, 0, 0};
2552 int i;
2553 int bitsize, nelts, nunits, units_per;
2555 /* This is hairy. We have a quantity of known size. real_to_target
2556 will put it into an array of *host* longs, 32 bits per element
2557 (even if long is more than 32 bits). We need to determine the
2558 number of array elements that are occupied (nelts) and the number
2559 of *target* min-addressable units that will be occupied in the
2560 object file (nunits). We cannot assume that 32 divides the
2561 mode's bitsize (size * BITS_PER_UNIT) evenly.
2563 size * BITS_PER_UNIT is used here to make sure that padding bits
2564 (which might appear at either end of the value; real_to_target
2565 will include the padding bits in its output array) are included. */
2567 nunits = GET_MODE_SIZE (mode);
2568 bitsize = nunits * BITS_PER_UNIT;
2569 nelts = CEIL (bitsize, 32);
2570 units_per = 32 / BITS_PER_UNIT;
2572 real_to_target (data, &d, mode);
2574 /* Put out the first word with the specified alignment. */
2575 assemble_integer (GEN_INT (data[0]), MIN (nunits, units_per), align, 1);
2576 nunits -= units_per;
2578 /* Subsequent words need only 32-bit alignment. */
2579 align = min_align (align, 32);
2581 for (i = 1; i < nelts; i++)
2583 assemble_integer (GEN_INT (data[i]), MIN (nunits, units_per), align, 1);
2584 nunits -= units_per;
2588 /* Given an expression EXP with a constant value,
2589 reduce it to the sum of an assembler symbol and an integer.
2590 Store them both in the structure *VALUE.
2591 EXP must be reducible. */
2593 struct addr_const {
2594 rtx base;
2595 HOST_WIDE_INT offset;
2598 static void
2599 decode_addr_const (tree exp, struct addr_const *value)
2601 tree target = TREE_OPERAND (exp, 0);
2602 int offset = 0;
2603 rtx x;
2605 while (1)
2607 if (TREE_CODE (target) == COMPONENT_REF
2608 && host_integerp (byte_position (TREE_OPERAND (target, 1)), 0))
2610 offset += int_byte_position (TREE_OPERAND (target, 1));
2611 target = TREE_OPERAND (target, 0);
2613 else if (TREE_CODE (target) == ARRAY_REF
2614 || TREE_CODE (target) == ARRAY_RANGE_REF)
2616 offset += (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (target)), 1)
2617 * tree_low_cst (TREE_OPERAND (target, 1), 0));
2618 target = TREE_OPERAND (target, 0);
2620 else if (TREE_CODE (target) == MEM_REF
2621 && TREE_CODE (TREE_OPERAND (target, 0)) == ADDR_EXPR)
2623 offset += mem_ref_offset (target).low;
2624 target = TREE_OPERAND (TREE_OPERAND (target, 0), 0);
2626 else if (TREE_CODE (target) == INDIRECT_REF
2627 && TREE_CODE (TREE_OPERAND (target, 0)) == NOP_EXPR
2628 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (target, 0), 0))
2629 == ADDR_EXPR)
2630 target = TREE_OPERAND (TREE_OPERAND (TREE_OPERAND (target, 0), 0), 0);
2631 else
2632 break;
2635 switch (TREE_CODE (target))
2637 case VAR_DECL:
2638 case FUNCTION_DECL:
2639 x = DECL_RTL (target);
2640 break;
2642 case LABEL_DECL:
2643 x = gen_rtx_MEM (FUNCTION_MODE,
2644 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2645 break;
2647 case REAL_CST:
2648 case FIXED_CST:
2649 case STRING_CST:
2650 case COMPLEX_CST:
2651 case CONSTRUCTOR:
2652 case INTEGER_CST:
2653 x = output_constant_def (target, 1);
2654 break;
2656 default:
2657 gcc_unreachable ();
2660 gcc_assert (MEM_P (x));
2661 x = XEXP (x, 0);
2663 value->base = x;
2664 value->offset = offset;
2668 static GTY((param_is (struct constant_descriptor_tree)))
2669 htab_t const_desc_htab;
2671 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2673 /* Constant pool accessor function. */
2675 htab_t
2676 constant_pool_htab (void)
2678 return const_desc_htab;
2681 /* Compute a hash code for a constant expression. */
2683 static hashval_t
2684 const_desc_hash (const void *ptr)
2686 return ((const struct constant_descriptor_tree *)ptr)->hash;
2689 static hashval_t
2690 const_hash_1 (const tree exp)
2692 const char *p;
2693 hashval_t hi;
2694 int len, i;
2695 enum tree_code code = TREE_CODE (exp);
2697 /* Either set P and LEN to the address and len of something to hash and
2698 exit the switch or return a value. */
2700 switch (code)
2702 case INTEGER_CST:
2703 p = (char *) &TREE_INT_CST (exp);
2704 len = sizeof TREE_INT_CST (exp);
2705 break;
2707 case REAL_CST:
2708 return real_hash (TREE_REAL_CST_PTR (exp));
2710 case FIXED_CST:
2711 return fixed_hash (TREE_FIXED_CST_PTR (exp));
2713 case STRING_CST:
2714 p = TREE_STRING_POINTER (exp);
2715 len = TREE_STRING_LENGTH (exp);
2716 break;
2718 case COMPLEX_CST:
2719 return (const_hash_1 (TREE_REALPART (exp)) * 5
2720 + const_hash_1 (TREE_IMAGPART (exp)));
2722 case VECTOR_CST:
2724 unsigned i;
2726 hi = 7 + VECTOR_CST_NELTS (exp);
2728 for (i = 0; i < VECTOR_CST_NELTS (exp); ++i)
2729 hi = hi * 563 + const_hash_1 (VECTOR_CST_ELT (exp, i));
2731 return hi;
2734 case CONSTRUCTOR:
2736 unsigned HOST_WIDE_INT idx;
2737 tree value;
2739 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2741 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
2742 if (value)
2743 hi = hi * 603 + const_hash_1 (value);
2745 return hi;
2748 case ADDR_EXPR:
2749 case FDESC_EXPR:
2751 struct addr_const value;
2753 decode_addr_const (exp, &value);
2754 switch (GET_CODE (value.base))
2756 case SYMBOL_REF:
2757 /* Don't hash the address of the SYMBOL_REF;
2758 only use the offset and the symbol name. */
2759 hi = value.offset;
2760 p = XSTR (value.base, 0);
2761 for (i = 0; p[i] != 0; i++)
2762 hi = ((hi * 613) + (unsigned) (p[i]));
2763 break;
2765 case LABEL_REF:
2766 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13;
2767 break;
2769 default:
2770 gcc_unreachable ();
2773 return hi;
2775 case PLUS_EXPR:
2776 case POINTER_PLUS_EXPR:
2777 case MINUS_EXPR:
2778 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2779 + const_hash_1 (TREE_OPERAND (exp, 1)));
2781 CASE_CONVERT:
2782 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
2784 default:
2785 /* A language specific constant. Just hash the code. */
2786 return code;
2789 /* Compute hashing function. */
2790 hi = len;
2791 for (i = 0; i < len; i++)
2792 hi = ((hi * 613) + (unsigned) (p[i]));
2794 return hi;
2797 /* Wrapper of compare_constant, for the htab interface. */
2798 static int
2799 const_desc_eq (const void *p1, const void *p2)
2801 const struct constant_descriptor_tree *const c1
2802 = (const struct constant_descriptor_tree *) p1;
2803 const struct constant_descriptor_tree *const c2
2804 = (const struct constant_descriptor_tree *) p2;
2805 if (c1->hash != c2->hash)
2806 return 0;
2807 return compare_constant (c1->value, c2->value);
2810 /* Compare t1 and t2, and return 1 only if they are known to result in
2811 the same bit pattern on output. */
2813 static int
2814 compare_constant (const tree t1, const tree t2)
2816 enum tree_code typecode;
2818 if (t1 == NULL_TREE)
2819 return t2 == NULL_TREE;
2820 if (t2 == NULL_TREE)
2821 return 0;
2823 if (TREE_CODE (t1) != TREE_CODE (t2))
2824 return 0;
2826 switch (TREE_CODE (t1))
2828 case INTEGER_CST:
2829 /* Integer constants are the same only if the same width of type. */
2830 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2831 return 0;
2832 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2833 return 0;
2834 return tree_int_cst_equal (t1, t2);
2836 case REAL_CST:
2837 /* Real constants are the same only if the same width of type. */
2838 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2839 return 0;
2841 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
2843 case FIXED_CST:
2844 /* Fixed constants are the same only if the same width of type. */
2845 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2846 return 0;
2848 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
2850 case STRING_CST:
2851 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2852 return 0;
2854 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
2855 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
2856 TREE_STRING_LENGTH (t1)));
2858 case COMPLEX_CST:
2859 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
2860 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
2862 case VECTOR_CST:
2864 unsigned i;
2866 if (VECTOR_CST_NELTS (t1) != VECTOR_CST_NELTS (t2))
2867 return 0;
2869 for (i = 0; i < VECTOR_CST_NELTS (t1); ++i)
2870 if (!compare_constant (VECTOR_CST_ELT (t1, i),
2871 VECTOR_CST_ELT (t2, i)))
2872 return 0;
2874 return 1;
2877 case CONSTRUCTOR:
2879 VEC(constructor_elt, gc) *v1, *v2;
2880 unsigned HOST_WIDE_INT idx;
2882 typecode = TREE_CODE (TREE_TYPE (t1));
2883 if (typecode != TREE_CODE (TREE_TYPE (t2)))
2884 return 0;
2886 if (typecode == ARRAY_TYPE)
2888 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
2889 /* For arrays, check that the sizes all match. */
2890 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
2891 || size_1 == -1
2892 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
2893 return 0;
2895 else
2897 /* For record and union constructors, require exact type
2898 equality. */
2899 if (TREE_TYPE (t1) != TREE_TYPE (t2))
2900 return 0;
2903 v1 = CONSTRUCTOR_ELTS (t1);
2904 v2 = CONSTRUCTOR_ELTS (t2);
2905 if (VEC_length (constructor_elt, v1)
2906 != VEC_length (constructor_elt, v2))
2907 return 0;
2909 for (idx = 0; idx < VEC_length (constructor_elt, v1); ++idx)
2911 constructor_elt *c1 = VEC_index (constructor_elt, v1, idx);
2912 constructor_elt *c2 = VEC_index (constructor_elt, v2, idx);
2914 /* Check that each value is the same... */
2915 if (!compare_constant (c1->value, c2->value))
2916 return 0;
2917 /* ... and that they apply to the same fields! */
2918 if (typecode == ARRAY_TYPE)
2920 if (!compare_constant (c1->index, c2->index))
2921 return 0;
2923 else
2925 if (c1->index != c2->index)
2926 return 0;
2930 return 1;
2933 case ADDR_EXPR:
2934 case FDESC_EXPR:
2936 struct addr_const value1, value2;
2937 enum rtx_code code;
2938 int ret;
2940 decode_addr_const (t1, &value1);
2941 decode_addr_const (t2, &value2);
2943 if (value1.offset != value2.offset)
2944 return 0;
2946 code = GET_CODE (value1.base);
2947 if (code != GET_CODE (value2.base))
2948 return 0;
2950 switch (code)
2952 case SYMBOL_REF:
2953 ret = (strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
2954 break;
2956 case LABEL_REF:
2957 ret = (CODE_LABEL_NUMBER (XEXP (value1.base, 0))
2958 == CODE_LABEL_NUMBER (XEXP (value2.base, 0)));
2959 break;
2961 default:
2962 gcc_unreachable ();
2964 return ret;
2967 case PLUS_EXPR:
2968 case POINTER_PLUS_EXPR:
2969 case MINUS_EXPR:
2970 case RANGE_EXPR:
2971 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
2972 && compare_constant(TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
2974 CASE_CONVERT:
2975 case VIEW_CONVERT_EXPR:
2976 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
2978 default:
2979 return 0;
2982 gcc_unreachable ();
2985 /* Make a copy of the whole tree structure for a constant. This
2986 handles the same types of nodes that compare_constant handles. */
2988 static tree
2989 copy_constant (tree exp)
2991 switch (TREE_CODE (exp))
2993 case ADDR_EXPR:
2994 /* For ADDR_EXPR, we do not want to copy the decl whose address
2995 is requested. We do want to copy constants though. */
2996 if (CONSTANT_CLASS_P (TREE_OPERAND (exp, 0)))
2997 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
2998 copy_constant (TREE_OPERAND (exp, 0)));
2999 else
3000 return copy_node (exp);
3002 case INTEGER_CST:
3003 case REAL_CST:
3004 case FIXED_CST:
3005 case STRING_CST:
3006 return copy_node (exp);
3008 case COMPLEX_CST:
3009 return build_complex (TREE_TYPE (exp),
3010 copy_constant (TREE_REALPART (exp)),
3011 copy_constant (TREE_IMAGPART (exp)));
3013 case PLUS_EXPR:
3014 case POINTER_PLUS_EXPR:
3015 case MINUS_EXPR:
3016 return build2 (TREE_CODE (exp), TREE_TYPE (exp),
3017 copy_constant (TREE_OPERAND (exp, 0)),
3018 copy_constant (TREE_OPERAND (exp, 1)));
3020 CASE_CONVERT:
3021 case VIEW_CONVERT_EXPR:
3022 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
3023 copy_constant (TREE_OPERAND (exp, 0)));
3025 case VECTOR_CST:
3026 return build_vector (TREE_TYPE (exp), VECTOR_CST_ELTS (exp));
3028 case CONSTRUCTOR:
3030 tree copy = copy_node (exp);
3031 VEC(constructor_elt, gc) *v;
3032 unsigned HOST_WIDE_INT idx;
3033 tree purpose, value;
3035 v = VEC_alloc(constructor_elt, gc, VEC_length(constructor_elt,
3036 CONSTRUCTOR_ELTS (exp)));
3037 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (exp), idx, purpose, value)
3039 constructor_elt *ce = VEC_quick_push (constructor_elt, v, NULL);
3040 ce->index = purpose;
3041 ce->value = copy_constant (value);
3043 CONSTRUCTOR_ELTS (copy) = v;
3044 return copy;
3047 default:
3048 gcc_unreachable ();
3052 /* Return the section into which constant EXP should be placed. */
3054 static section *
3055 get_constant_section (tree exp, unsigned int align)
3057 return targetm.asm_out.select_section (exp,
3058 compute_reloc_for_constant (exp),
3059 align);
3062 /* Return the size of constant EXP in bytes. */
3064 static HOST_WIDE_INT
3065 get_constant_size (tree exp)
3067 HOST_WIDE_INT size;
3069 size = int_size_in_bytes (TREE_TYPE (exp));
3070 if (TREE_CODE (exp) == STRING_CST)
3071 size = MAX (TREE_STRING_LENGTH (exp), size);
3072 return size;
3075 /* Subroutine of output_constant_def:
3076 No constant equal to EXP is known to have been output.
3077 Make a constant descriptor to enter EXP in the hash table.
3078 Assign the label number and construct RTL to refer to the
3079 constant's location in memory.
3080 Caller is responsible for updating the hash table. */
3082 static struct constant_descriptor_tree *
3083 build_constant_desc (tree exp)
3085 struct constant_descriptor_tree *desc;
3086 rtx symbol, rtl;
3087 char label[256];
3088 int labelno;
3089 tree decl;
3091 desc = ggc_alloc_constant_descriptor_tree ();
3092 desc->value = copy_constant (exp);
3094 /* Propagate marked-ness to copied constant. */
3095 if (flag_mudflap && mf_marked_p (exp))
3096 mf_mark (desc->value);
3098 /* Create a string containing the label name, in LABEL. */
3099 labelno = const_labelno++;
3100 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3102 /* Construct the VAR_DECL associated with the constant. */
3103 decl = build_decl (UNKNOWN_LOCATION, VAR_DECL, get_identifier (label),
3104 TREE_TYPE (exp));
3105 DECL_ARTIFICIAL (decl) = 1;
3106 DECL_IGNORED_P (decl) = 1;
3107 TREE_READONLY (decl) = 1;
3108 TREE_STATIC (decl) = 1;
3109 TREE_ADDRESSABLE (decl) = 1;
3110 /* We don't set the RTL yet as this would cause varpool to assume that the
3111 variable is referenced. Moreover, it would just be dropped in LTO mode.
3112 Instead we set the flag that will be recognized in make_decl_rtl. */
3113 DECL_IN_CONSTANT_POOL (decl) = 1;
3114 DECL_INITIAL (decl) = desc->value;
3115 /* ??? CONSTANT_ALIGNMENT hasn't been updated for vector types on most
3116 architectures so use DATA_ALIGNMENT as well, except for strings. */
3117 if (TREE_CODE (exp) == STRING_CST)
3119 #ifdef CONSTANT_ALIGNMENT
3120 DECL_ALIGN (decl) = CONSTANT_ALIGNMENT (exp, DECL_ALIGN (decl));
3121 #endif
3123 else
3124 align_variable (decl, 0);
3126 /* Now construct the SYMBOL_REF and the MEM. */
3127 if (use_object_blocks_p ())
3129 section *sect = get_constant_section (exp, DECL_ALIGN (decl));
3130 symbol = create_block_symbol (ggc_strdup (label),
3131 get_block_for_section (sect), -1);
3133 else
3134 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3135 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3136 SET_SYMBOL_REF_DECL (symbol, decl);
3137 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3139 rtl = gen_const_mem (TYPE_MODE (TREE_TYPE (exp)), symbol);
3140 set_mem_attributes (rtl, exp, 1);
3141 set_mem_alias_set (rtl, 0);
3142 set_mem_alias_set (rtl, const_alias_set);
3144 /* We cannot share RTX'es in pool entries.
3145 Mark this piece of RTL as required for unsharing. */
3146 RTX_FLAG (rtl, used) = 1;
3148 /* Set flags or add text to the name to record information, such as
3149 that it is a local symbol. If the name is changed, the macro
3150 ASM_OUTPUT_LABELREF will have to know how to strip this
3151 information. This call might invalidate our local variable
3152 SYMBOL; we can't use it afterward. */
3153 targetm.encode_section_info (exp, rtl, true);
3155 desc->rtl = rtl;
3157 return desc;
3160 /* Return an rtx representing a reference to constant data in memory
3161 for the constant expression EXP.
3163 If assembler code for such a constant has already been output,
3164 return an rtx to refer to it.
3165 Otherwise, output such a constant in memory
3166 and generate an rtx for it.
3168 If DEFER is nonzero, this constant can be deferred and output only
3169 if referenced in the function after all optimizations.
3171 `const_desc_table' records which constants already have label strings. */
3174 output_constant_def (tree exp, int defer)
3176 struct constant_descriptor_tree *desc;
3177 struct constant_descriptor_tree key;
3178 void **loc;
3180 /* Look up EXP in the table of constant descriptors. If we didn't find
3181 it, create a new one. */
3182 key.value = exp;
3183 key.hash = const_hash_1 (exp);
3184 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3186 desc = (struct constant_descriptor_tree *) *loc;
3187 if (desc == 0)
3189 desc = build_constant_desc (exp);
3190 desc->hash = key.hash;
3191 *loc = desc;
3194 maybe_output_constant_def_contents (desc, defer);
3195 return desc->rtl;
3198 /* Subroutine of output_constant_def: Decide whether or not we need to
3199 output the constant DESC now, and if so, do it. */
3200 static void
3201 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3202 int defer)
3204 rtx symbol = XEXP (desc->rtl, 0);
3205 tree exp = desc->value;
3207 if (flag_syntax_only)
3208 return;
3210 if (TREE_ASM_WRITTEN (exp))
3211 /* Already output; don't do it again. */
3212 return;
3214 /* We can always defer constants as long as the context allows
3215 doing so. */
3216 if (defer)
3218 /* Increment n_deferred_constants if it exists. It needs to be at
3219 least as large as the number of constants actually referred to
3220 by the function. If it's too small we'll stop looking too early
3221 and fail to emit constants; if it's too large we'll only look
3222 through the entire function when we could have stopped earlier. */
3223 if (cfun)
3224 n_deferred_constants++;
3225 return;
3228 output_constant_def_contents (symbol);
3231 /* Subroutine of output_constant_def_contents. Output the definition
3232 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3233 constant's alignment in bits. */
3235 static void
3236 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3238 HOST_WIDE_INT size;
3240 size = get_constant_size (exp);
3242 /* Do any machine/system dependent processing of the constant. */
3243 targetm.asm_out.declare_constant_name (asm_out_file, label, exp, size);
3245 /* Output the value of EXP. */
3246 output_constant (exp, size, align);
3249 /* We must output the constant data referred to by SYMBOL; do so. */
3251 static void
3252 output_constant_def_contents (rtx symbol)
3254 tree decl = SYMBOL_REF_DECL (symbol);
3255 tree exp = DECL_INITIAL (decl);
3256 unsigned int align;
3258 /* Make sure any other constants whose addresses appear in EXP
3259 are assigned label numbers. */
3260 output_addressed_constants (exp);
3262 /* We are no longer deferring this constant. */
3263 TREE_ASM_WRITTEN (decl) = TREE_ASM_WRITTEN (exp) = 1;
3265 /* If the constant is part of an object block, make sure that the
3266 decl has been positioned within its block, but do not write out
3267 its definition yet. output_object_blocks will do that later. */
3268 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3269 place_block_symbol (symbol);
3270 else
3272 align = DECL_ALIGN (decl);
3273 switch_to_section (get_constant_section (exp, align));
3274 if (align > BITS_PER_UNIT)
3275 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3276 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3278 if (flag_mudflap)
3279 mudflap_enqueue_constant (exp);
3282 /* Look up EXP in the table of constant descriptors. Return the rtl
3283 if it has been emitted, else null. */
3286 lookup_constant_def (tree exp)
3288 struct constant_descriptor_tree *desc;
3289 struct constant_descriptor_tree key;
3291 key.value = exp;
3292 key.hash = const_hash_1 (exp);
3293 desc = (struct constant_descriptor_tree *)
3294 htab_find_with_hash (const_desc_htab, &key, key.hash);
3296 return (desc ? desc->rtl : NULL_RTX);
3299 /* Return a tree representing a reference to constant data in memory
3300 for the constant expression EXP.
3302 This is the counterpart of output_constant_def at the Tree level. */
3304 tree
3305 tree_output_constant_def (tree exp)
3307 struct constant_descriptor_tree *desc, key;
3308 void **loc;
3309 tree decl;
3311 /* Look up EXP in the table of constant descriptors. If we didn't find
3312 it, create a new one. */
3313 key.value = exp;
3314 key.hash = const_hash_1 (exp);
3315 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3317 desc = (struct constant_descriptor_tree *) *loc;
3318 if (desc == 0)
3320 desc = build_constant_desc (exp);
3321 desc->hash = key.hash;
3322 *loc = desc;
3325 decl = SYMBOL_REF_DECL (XEXP (desc->rtl, 0));
3326 varpool_finalize_decl (decl);
3327 return decl;
3330 /* Used in the hash tables to avoid outputting the same constant
3331 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3332 are output once per function, not once per file. */
3333 /* ??? Only a few targets need per-function constant pools. Most
3334 can use one per-file pool. Should add a targetm bit to tell the
3335 difference. */
3337 struct GTY(()) rtx_constant_pool {
3338 /* Pointers to first and last constant in pool, as ordered by offset. */
3339 struct constant_descriptor_rtx *first;
3340 struct constant_descriptor_rtx *last;
3342 /* Hash facility for making memory-constants from constant rtl-expressions.
3343 It is used on RISC machines where immediate integer arguments and
3344 constant addresses are restricted so that such constants must be stored
3345 in memory. */
3346 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_htab;
3348 /* Current offset in constant pool (does not include any
3349 machine-specific header). */
3350 HOST_WIDE_INT offset;
3353 struct GTY((chain_next ("%h.next"))) constant_descriptor_rtx {
3354 struct constant_descriptor_rtx *next;
3355 rtx mem;
3356 rtx sym;
3357 rtx constant;
3358 HOST_WIDE_INT offset;
3359 hashval_t hash;
3360 enum machine_mode mode;
3361 unsigned int align;
3362 int labelno;
3363 int mark;
3366 /* Hash and compare functions for const_rtx_htab. */
3368 static hashval_t
3369 const_desc_rtx_hash (const void *ptr)
3371 const struct constant_descriptor_rtx *const desc
3372 = (const struct constant_descriptor_rtx *) ptr;
3373 return desc->hash;
3376 static int
3377 const_desc_rtx_eq (const void *a, const void *b)
3379 const struct constant_descriptor_rtx *const x
3380 = (const struct constant_descriptor_rtx *) a;
3381 const struct constant_descriptor_rtx *const y
3382 = (const struct constant_descriptor_rtx *) b;
3384 if (x->mode != y->mode)
3385 return 0;
3386 return rtx_equal_p (x->constant, y->constant);
3389 /* This is the worker function for const_rtx_hash, called via for_each_rtx. */
3391 static int
3392 const_rtx_hash_1 (rtx *xp, void *data)
3394 unsigned HOST_WIDE_INT hwi;
3395 enum machine_mode mode;
3396 enum rtx_code code;
3397 hashval_t h, *hp;
3398 rtx x;
3400 x = *xp;
3401 code = GET_CODE (x);
3402 mode = GET_MODE (x);
3403 h = (hashval_t) code * 1048573 + mode;
3405 switch (code)
3407 case CONST_INT:
3408 hwi = INTVAL (x);
3409 fold_hwi:
3411 int shift = sizeof (hashval_t) * CHAR_BIT;
3412 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3413 int i;
3415 h ^= (hashval_t) hwi;
3416 for (i = 1; i < n; ++i)
3418 hwi >>= shift;
3419 h ^= (hashval_t) hwi;
3422 break;
3424 case CONST_DOUBLE:
3425 if (mode == VOIDmode)
3427 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3428 goto fold_hwi;
3430 else
3431 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3432 break;
3434 case CONST_FIXED:
3435 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3436 break;
3438 case CONST_VECTOR:
3440 int i;
3441 for (i = XVECLEN (x, 0); i-- > 0; )
3442 h = h * 251 + const_rtx_hash_1 (&XVECEXP (x, 0, i), data);
3444 break;
3446 case SYMBOL_REF:
3447 h ^= htab_hash_string (XSTR (x, 0));
3448 break;
3450 case LABEL_REF:
3451 h = h * 251 + CODE_LABEL_NUMBER (XEXP (x, 0));
3452 break;
3454 case UNSPEC:
3455 case UNSPEC_VOLATILE:
3456 h = h * 251 + XINT (x, 1);
3457 break;
3459 default:
3460 break;
3463 hp = (hashval_t *) data;
3464 *hp = *hp * 509 + h;
3465 return 0;
3468 /* Compute a hash value for X, which should be a constant. */
3470 static hashval_t
3471 const_rtx_hash (rtx x)
3473 hashval_t h = 0;
3474 for_each_rtx (&x, const_rtx_hash_1, &h);
3475 return h;
3479 /* Create and return a new rtx constant pool. */
3481 static struct rtx_constant_pool *
3482 create_constant_pool (void)
3484 struct rtx_constant_pool *pool;
3486 pool = ggc_alloc_rtx_constant_pool ();
3487 pool->const_rtx_htab = htab_create_ggc (31, const_desc_rtx_hash,
3488 const_desc_rtx_eq, NULL);
3489 pool->first = NULL;
3490 pool->last = NULL;
3491 pool->offset = 0;
3492 return pool;
3495 /* Initialize constant pool hashing for a new function. */
3497 void
3498 init_varasm_status (void)
3500 crtl->varasm.pool = create_constant_pool ();
3501 crtl->varasm.deferred_constants = 0;
3504 /* Given a MINUS expression, simplify it if both sides
3505 include the same symbol. */
3508 simplify_subtraction (rtx x)
3510 rtx r = simplify_rtx (x);
3511 return r ? r : x;
3514 /* Given a constant rtx X, make (or find) a memory constant for its value
3515 and return a MEM rtx to refer to it in memory. */
3518 force_const_mem (enum machine_mode mode, rtx x)
3520 struct constant_descriptor_rtx *desc, tmp;
3521 struct rtx_constant_pool *pool;
3522 char label[256];
3523 rtx def, symbol;
3524 hashval_t hash;
3525 unsigned int align;
3526 void **slot;
3528 /* If we're not allowed to drop X into the constant pool, don't. */
3529 if (targetm.cannot_force_const_mem (mode, x))
3530 return NULL_RTX;
3532 /* Record that this function has used a constant pool entry. */
3533 crtl->uses_const_pool = 1;
3535 /* Decide which pool to use. */
3536 pool = (targetm.use_blocks_for_constant_p (mode, x)
3537 ? shared_constant_pool
3538 : crtl->varasm.pool);
3540 /* Lookup the value in the hashtable. */
3541 tmp.constant = x;
3542 tmp.mode = mode;
3543 hash = const_rtx_hash (x);
3544 slot = htab_find_slot_with_hash (pool->const_rtx_htab, &tmp, hash, INSERT);
3545 desc = (struct constant_descriptor_rtx *) *slot;
3547 /* If the constant was already present, return its memory. */
3548 if (desc)
3549 return copy_rtx (desc->mem);
3551 /* Otherwise, create a new descriptor. */
3552 desc = ggc_alloc_constant_descriptor_rtx ();
3553 *slot = desc;
3555 /* Align the location counter as required by EXP's data type. */
3556 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3557 #ifdef CONSTANT_ALIGNMENT
3559 tree type = lang_hooks.types.type_for_mode (mode, 0);
3560 if (type != NULL_TREE)
3561 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3563 #endif
3565 pool->offset += (align / BITS_PER_UNIT) - 1;
3566 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3568 desc->next = NULL;
3569 desc->constant = copy_rtx (tmp.constant);
3570 desc->offset = pool->offset;
3571 desc->hash = hash;
3572 desc->mode = mode;
3573 desc->align = align;
3574 desc->labelno = const_labelno;
3575 desc->mark = 0;
3577 pool->offset += GET_MODE_SIZE (mode);
3578 if (pool->last)
3579 pool->last->next = desc;
3580 else
3581 pool->first = pool->last = desc;
3582 pool->last = desc;
3584 /* Create a string containing the label name, in LABEL. */
3585 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3586 ++const_labelno;
3588 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3589 the constants pool. */
3590 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3592 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3593 symbol = create_block_symbol (ggc_strdup (label),
3594 get_block_for_section (sect), -1);
3596 else
3597 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3598 desc->sym = symbol;
3599 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3600 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3601 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3603 /* Construct the MEM. */
3604 desc->mem = def = gen_const_mem (mode, symbol);
3605 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3606 set_mem_align (def, align);
3608 /* If we're dropping a label to the constant pool, make sure we
3609 don't delete it. */
3610 if (GET_CODE (x) == LABEL_REF)
3611 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3613 return copy_rtx (def);
3616 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3619 get_pool_constant (rtx addr)
3621 return SYMBOL_REF_CONSTANT (addr)->constant;
3624 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3625 and whether it has been output or not. */
3628 get_pool_constant_mark (rtx addr, bool *pmarked)
3630 struct constant_descriptor_rtx *desc;
3632 desc = SYMBOL_REF_CONSTANT (addr);
3633 *pmarked = (desc->mark != 0);
3634 return desc->constant;
3637 /* Similar, return the mode. */
3639 enum machine_mode
3640 get_pool_mode (const_rtx addr)
3642 return SYMBOL_REF_CONSTANT (addr)->mode;
3645 /* Return the size of the constant pool. */
3648 get_pool_size (void)
3650 return crtl->varasm.pool->offset;
3653 /* Worker function for output_constant_pool_1. Emit assembly for X
3654 in MODE with known alignment ALIGN. */
3656 static void
3657 output_constant_pool_2 (enum machine_mode mode, rtx x, unsigned int align)
3659 switch (GET_MODE_CLASS (mode))
3661 case MODE_FLOAT:
3662 case MODE_DECIMAL_FLOAT:
3664 REAL_VALUE_TYPE r;
3666 gcc_assert (GET_CODE (x) == CONST_DOUBLE);
3667 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3668 assemble_real (r, mode, align);
3669 break;
3672 case MODE_INT:
3673 case MODE_PARTIAL_INT:
3674 case MODE_FRACT:
3675 case MODE_UFRACT:
3676 case MODE_ACCUM:
3677 case MODE_UACCUM:
3678 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3679 break;
3681 case MODE_VECTOR_FLOAT:
3682 case MODE_VECTOR_INT:
3683 case MODE_VECTOR_FRACT:
3684 case MODE_VECTOR_UFRACT:
3685 case MODE_VECTOR_ACCUM:
3686 case MODE_VECTOR_UACCUM:
3688 int i, units;
3689 enum machine_mode submode = GET_MODE_INNER (mode);
3690 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3692 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3693 units = CONST_VECTOR_NUNITS (x);
3695 for (i = 0; i < units; i++)
3697 rtx elt = CONST_VECTOR_ELT (x, i);
3698 output_constant_pool_2 (submode, elt, i ? subalign : align);
3701 break;
3703 default:
3704 gcc_unreachable ();
3708 /* Worker function for output_constant_pool. Emit constant DESC,
3709 giving it ALIGN bits of alignment. */
3711 static void
3712 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3713 unsigned int align)
3715 rtx x, tmp;
3717 x = desc->constant;
3719 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3720 whose CODE_LABEL has been deleted. This can occur if a jump table
3721 is eliminated by optimization. If so, write a constant of zero
3722 instead. Note that this can also happen by turning the
3723 CODE_LABEL into a NOTE. */
3724 /* ??? This seems completely and utterly wrong. Certainly it's
3725 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3726 functioning even with INSN_DELETED_P and friends. */
3728 tmp = x;
3729 switch (GET_CODE (tmp))
3731 case CONST:
3732 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3733 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
3734 break;
3735 tmp = XEXP (XEXP (tmp, 0), 0);
3736 /* FALLTHRU */
3738 case LABEL_REF:
3739 tmp = XEXP (tmp, 0);
3740 gcc_assert (!INSN_DELETED_P (tmp));
3741 gcc_assert (!NOTE_P (tmp)
3742 || NOTE_KIND (tmp) != NOTE_INSN_DELETED);
3743 break;
3745 default:
3746 break;
3749 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3750 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3751 align, desc->labelno, done);
3752 #endif
3754 assemble_align (align);
3756 /* Output the label. */
3757 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3759 /* Output the data. */
3760 output_constant_pool_2 (desc->mode, x, align);
3762 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3763 sections have proper size. */
3764 if (align > GET_MODE_BITSIZE (desc->mode)
3765 && in_section
3766 && (in_section->common.flags & SECTION_MERGE))
3767 assemble_align (align);
3769 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3770 done:
3771 #endif
3772 return;
3775 /* Given a SYMBOL_REF CURRENT_RTX, mark it and all constants it refers
3776 to as used. Emit referenced deferred strings. This function can
3777 be used with for_each_rtx to mark all SYMBOL_REFs in an rtx. */
3779 static int
3780 mark_constant (rtx *current_rtx, void *data ATTRIBUTE_UNUSED)
3782 rtx x = *current_rtx;
3784 if (x == NULL_RTX || GET_CODE (x) != SYMBOL_REF)
3785 return 0;
3787 if (CONSTANT_POOL_ADDRESS_P (x))
3789 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
3790 if (desc->mark == 0)
3792 desc->mark = 1;
3793 for_each_rtx (&desc->constant, mark_constant, NULL);
3796 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3798 tree decl = SYMBOL_REF_DECL (x);
3799 if (!TREE_ASM_WRITTEN (DECL_INITIAL (decl)))
3801 n_deferred_constants--;
3802 output_constant_def_contents (x);
3806 return -1;
3809 /* Look through appropriate parts of INSN, marking all entries in the
3810 constant pool which are actually being used. Entries that are only
3811 referenced by other constants are also marked as used. Emit
3812 deferred strings that are used. */
3814 static void
3815 mark_constants (rtx insn)
3817 if (!INSN_P (insn))
3818 return;
3820 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3821 insns, not any notes that may be attached. We don't want to mark
3822 a constant just because it happens to appear in a REG_EQUIV note. */
3823 if (GET_CODE (PATTERN (insn)) == SEQUENCE)
3825 rtx seq = PATTERN (insn);
3826 int i, n = XVECLEN (seq, 0);
3827 for (i = 0; i < n; ++i)
3829 rtx subinsn = XVECEXP (seq, 0, i);
3830 if (INSN_P (subinsn))
3831 for_each_rtx (&PATTERN (subinsn), mark_constant, NULL);
3834 else
3835 for_each_rtx (&PATTERN (insn), mark_constant, NULL);
3838 /* Look through the instructions for this function, and mark all the
3839 entries in POOL which are actually being used. Emit deferred constants
3840 which have indeed been used. */
3842 static void
3843 mark_constant_pool (void)
3845 rtx insn, link;
3847 if (!crtl->uses_const_pool && n_deferred_constants == 0)
3848 return;
3850 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3851 mark_constants (insn);
3853 for (link = crtl->epilogue_delay_list;
3854 link;
3855 link = XEXP (link, 1))
3856 mark_constants (XEXP (link, 0));
3859 /* Write all the constants in POOL. */
3861 static void
3862 output_constant_pool_contents (struct rtx_constant_pool *pool)
3864 struct constant_descriptor_rtx *desc;
3866 for (desc = pool->first; desc ; desc = desc->next)
3867 if (desc->mark)
3869 /* If the constant is part of an object_block, make sure that
3870 the constant has been positioned within its block, but do not
3871 write out its definition yet. output_object_blocks will do
3872 that later. */
3873 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
3874 && SYMBOL_REF_BLOCK (desc->sym))
3875 place_block_symbol (desc->sym);
3876 else
3878 switch_to_section (targetm.asm_out.select_rtx_section
3879 (desc->mode, desc->constant, desc->align));
3880 output_constant_pool_1 (desc, desc->align);
3885 /* Mark all constants that are used in the current function, then write
3886 out the function's private constant pool. */
3888 static void
3889 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
3890 tree fndecl ATTRIBUTE_UNUSED)
3892 struct rtx_constant_pool *pool = crtl->varasm.pool;
3894 /* It is possible for gcc to call force_const_mem and then to later
3895 discard the instructions which refer to the constant. In such a
3896 case we do not need to output the constant. */
3897 mark_constant_pool ();
3899 #ifdef ASM_OUTPUT_POOL_PROLOGUE
3900 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
3901 #endif
3903 output_constant_pool_contents (pool);
3905 #ifdef ASM_OUTPUT_POOL_EPILOGUE
3906 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
3907 #endif
3910 /* Write the contents of the shared constant pool. */
3912 void
3913 output_shared_constant_pool (void)
3915 output_constant_pool_contents (shared_constant_pool);
3918 /* Determine what kind of relocations EXP may need. */
3921 compute_reloc_for_constant (tree exp)
3923 int reloc = 0, reloc2;
3924 tree tem;
3926 switch (TREE_CODE (exp))
3928 case ADDR_EXPR:
3929 case FDESC_EXPR:
3930 /* Go inside any operations that get_inner_reference can handle and see
3931 if what's inside is a constant: no need to do anything here for
3932 addresses of variables or functions. */
3933 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
3934 tem = TREE_OPERAND (tem, 0))
3937 if (TREE_CODE (tem) == MEM_REF
3938 && TREE_CODE (TREE_OPERAND (tem, 0)) == ADDR_EXPR)
3940 reloc = compute_reloc_for_constant (TREE_OPERAND (tem, 0));
3941 break;
3944 if (TREE_PUBLIC (tem))
3945 reloc |= 2;
3946 else
3947 reloc |= 1;
3948 break;
3950 case PLUS_EXPR:
3951 case POINTER_PLUS_EXPR:
3952 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3953 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
3954 break;
3956 case MINUS_EXPR:
3957 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3958 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
3959 /* The difference of two local labels is computable at link time. */
3960 if (reloc == 1 && reloc2 == 1)
3961 reloc = 0;
3962 else
3963 reloc |= reloc2;
3964 break;
3966 CASE_CONVERT:
3967 case VIEW_CONVERT_EXPR:
3968 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3969 break;
3971 case CONSTRUCTOR:
3973 unsigned HOST_WIDE_INT idx;
3974 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
3975 if (tem != 0)
3976 reloc |= compute_reloc_for_constant (tem);
3978 break;
3980 default:
3981 break;
3983 return reloc;
3986 /* Find all the constants whose addresses are referenced inside of EXP,
3987 and make sure assembler code with a label has been output for each one.
3988 Indicate whether an ADDR_EXPR has been encountered. */
3990 static void
3991 output_addressed_constants (tree exp)
3993 tree tem;
3995 switch (TREE_CODE (exp))
3997 case ADDR_EXPR:
3998 case FDESC_EXPR:
3999 /* Go inside any operations that get_inner_reference can handle and see
4000 if what's inside is a constant: no need to do anything here for
4001 addresses of variables or functions. */
4002 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4003 tem = TREE_OPERAND (tem, 0))
4006 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4007 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4008 tem = DECL_INITIAL (tem);
4010 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4011 output_constant_def (tem, 0);
4013 if (TREE_CODE (tem) == MEM_REF)
4014 output_addressed_constants (TREE_OPERAND (tem, 0));
4015 break;
4017 case PLUS_EXPR:
4018 case POINTER_PLUS_EXPR:
4019 case MINUS_EXPR:
4020 output_addressed_constants (TREE_OPERAND (exp, 1));
4021 /* Fall through. */
4023 CASE_CONVERT:
4024 case VIEW_CONVERT_EXPR:
4025 output_addressed_constants (TREE_OPERAND (exp, 0));
4026 break;
4028 case CONSTRUCTOR:
4030 unsigned HOST_WIDE_INT idx;
4031 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4032 if (tem != 0)
4033 output_addressed_constants (tem);
4035 break;
4037 default:
4038 break;
4042 /* Whether a constructor CTOR is a valid static constant initializer if all
4043 its elements are. This used to be internal to initializer_constant_valid_p
4044 and has been exposed to let other functions like categorize_ctor_elements
4045 evaluate the property while walking a constructor for other purposes. */
4047 bool
4048 constructor_static_from_elts_p (const_tree ctor)
4050 return (TREE_CONSTANT (ctor)
4051 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4052 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE
4053 || TREE_CODE (TREE_TYPE (ctor)) == ARRAY_TYPE));
4056 static tree initializer_constant_valid_p_1 (tree value, tree endtype,
4057 tree *cache);
4059 /* A subroutine of initializer_constant_valid_p. VALUE is a MINUS_EXPR,
4060 PLUS_EXPR or POINTER_PLUS_EXPR. This looks for cases of VALUE
4061 which are valid when ENDTYPE is an integer of any size; in
4062 particular, this does not accept a pointer minus a constant. This
4063 returns null_pointer_node if the VALUE is an absolute constant
4064 which can be used to initialize a static variable. Otherwise it
4065 returns NULL. */
4067 static tree
4068 narrowing_initializer_constant_valid_p (tree value, tree endtype, tree *cache)
4070 tree op0, op1;
4072 if (!INTEGRAL_TYPE_P (endtype))
4073 return NULL_TREE;
4075 op0 = TREE_OPERAND (value, 0);
4076 op1 = TREE_OPERAND (value, 1);
4078 /* Like STRIP_NOPS except allow the operand mode to widen. This
4079 works around a feature of fold that simplifies (int)(p1 - p2) to
4080 ((int)p1 - (int)p2) under the theory that the narrower operation
4081 is cheaper. */
4083 while (CONVERT_EXPR_P (op0)
4084 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4086 tree inner = TREE_OPERAND (op0, 0);
4087 if (inner == error_mark_node
4088 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4089 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
4090 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4091 break;
4092 op0 = inner;
4095 while (CONVERT_EXPR_P (op1)
4096 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4098 tree inner = TREE_OPERAND (op1, 0);
4099 if (inner == error_mark_node
4100 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4101 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
4102 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4103 break;
4104 op1 = inner;
4107 op0 = initializer_constant_valid_p_1 (op0, endtype, cache);
4108 if (!op0)
4109 return NULL_TREE;
4111 op1 = initializer_constant_valid_p_1 (op1, endtype,
4112 cache ? cache + 2 : NULL);
4113 /* Both initializers must be known. */
4114 if (op1)
4116 if (op0 == op1
4117 && (op0 == null_pointer_node
4118 || TREE_CODE (value) == MINUS_EXPR))
4119 return null_pointer_node;
4121 /* Support differences between labels. */
4122 if (TREE_CODE (op0) == LABEL_DECL
4123 && TREE_CODE (op1) == LABEL_DECL)
4124 return null_pointer_node;
4126 if (TREE_CODE (op0) == STRING_CST
4127 && TREE_CODE (op1) == STRING_CST
4128 && operand_equal_p (op0, op1, 1))
4129 return null_pointer_node;
4132 return NULL_TREE;
4135 /* Helper function of initializer_constant_valid_p.
4136 Return nonzero if VALUE is a valid constant-valued expression
4137 for use in initializing a static variable; one that can be an
4138 element of a "constant" initializer.
4140 Return null_pointer_node if the value is absolute;
4141 if it is relocatable, return the variable that determines the relocation.
4142 We assume that VALUE has been folded as much as possible;
4143 therefore, we do not need to check for such things as
4144 arithmetic-combinations of integers.
4146 Use CACHE (pointer to 2 tree values) for caching if non-NULL. */
4148 static tree
4149 initializer_constant_valid_p_1 (tree value, tree endtype, tree *cache)
4151 tree ret;
4153 switch (TREE_CODE (value))
4155 case CONSTRUCTOR:
4156 if (constructor_static_from_elts_p (value))
4158 unsigned HOST_WIDE_INT idx;
4159 tree elt;
4160 bool absolute = true;
4162 if (cache && cache[0] == value)
4163 return cache[1];
4164 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4166 tree reloc;
4167 reloc = initializer_constant_valid_p_1 (elt, TREE_TYPE (elt),
4168 NULL);
4169 if (!reloc)
4171 if (cache)
4173 cache[0] = value;
4174 cache[1] = NULL_TREE;
4176 return NULL_TREE;
4178 if (reloc != null_pointer_node)
4179 absolute = false;
4181 /* For a non-absolute relocation, there is no single
4182 variable that can be "the variable that determines the
4183 relocation." */
4184 if (cache)
4186 cache[0] = value;
4187 cache[1] = absolute ? null_pointer_node : error_mark_node;
4189 return absolute ? null_pointer_node : error_mark_node;
4192 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4194 case INTEGER_CST:
4195 case VECTOR_CST:
4196 case REAL_CST:
4197 case FIXED_CST:
4198 case STRING_CST:
4199 case COMPLEX_CST:
4200 return null_pointer_node;
4202 case ADDR_EXPR:
4203 case FDESC_EXPR:
4205 tree op0 = staticp (TREE_OPERAND (value, 0));
4206 if (op0)
4208 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out
4209 to be a constant, this is old-skool offsetof-like nonsense. */
4210 if (TREE_CODE (op0) == INDIRECT_REF
4211 && TREE_CONSTANT (TREE_OPERAND (op0, 0)))
4212 return null_pointer_node;
4213 /* Taking the address of a nested function involves a trampoline,
4214 unless we don't need or want one. */
4215 if (TREE_CODE (op0) == FUNCTION_DECL
4216 && DECL_STATIC_CHAIN (op0)
4217 && !TREE_NO_TRAMPOLINE (value))
4218 return NULL_TREE;
4219 /* "&{...}" requires a temporary to hold the constructed
4220 object. */
4221 if (TREE_CODE (op0) == CONSTRUCTOR)
4222 return NULL_TREE;
4224 return op0;
4227 case NON_LVALUE_EXPR:
4228 return initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4229 endtype, cache);
4231 case VIEW_CONVERT_EXPR:
4233 tree src = TREE_OPERAND (value, 0);
4234 tree src_type = TREE_TYPE (src);
4235 tree dest_type = TREE_TYPE (value);
4237 /* Allow view-conversions from aggregate to non-aggregate type only
4238 if the bit pattern is fully preserved afterwards; otherwise, the
4239 RTL expander won't be able to apply a subsequent transformation
4240 to the underlying constructor. */
4241 if (AGGREGATE_TYPE_P (src_type) && !AGGREGATE_TYPE_P (dest_type))
4243 if (TYPE_MODE (endtype) == TYPE_MODE (dest_type))
4244 return initializer_constant_valid_p_1 (src, endtype, cache);
4245 else
4246 return NULL_TREE;
4249 /* Allow all other kinds of view-conversion. */
4250 return initializer_constant_valid_p_1 (src, endtype, cache);
4253 CASE_CONVERT:
4255 tree src = TREE_OPERAND (value, 0);
4256 tree src_type = TREE_TYPE (src);
4257 tree dest_type = TREE_TYPE (value);
4259 /* Allow conversions between pointer types, floating-point
4260 types, and offset types. */
4261 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4262 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4263 || (TREE_CODE (dest_type) == OFFSET_TYPE
4264 && TREE_CODE (src_type) == OFFSET_TYPE))
4265 return initializer_constant_valid_p_1 (src, endtype, cache);
4267 /* Allow length-preserving conversions between integer types. */
4268 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4269 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4270 return initializer_constant_valid_p_1 (src, endtype, cache);
4272 /* Allow conversions between other integer types only if
4273 explicit value. */
4274 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type))
4276 tree inner = initializer_constant_valid_p_1 (src, endtype, cache);
4277 if (inner == null_pointer_node)
4278 return null_pointer_node;
4279 break;
4282 /* Allow (int) &foo provided int is as wide as a pointer. */
4283 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4284 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4285 return initializer_constant_valid_p_1 (src, endtype, cache);
4287 /* Likewise conversions from int to pointers, but also allow
4288 conversions from 0. */
4289 if ((POINTER_TYPE_P (dest_type)
4290 || TREE_CODE (dest_type) == OFFSET_TYPE)
4291 && INTEGRAL_TYPE_P (src_type))
4293 if (TREE_CODE (src) == INTEGER_CST
4294 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4295 return null_pointer_node;
4296 if (integer_zerop (src))
4297 return null_pointer_node;
4298 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4299 return initializer_constant_valid_p_1 (src, endtype, cache);
4302 /* Allow conversions to struct or union types if the value
4303 inside is okay. */
4304 if (TREE_CODE (dest_type) == RECORD_TYPE
4305 || TREE_CODE (dest_type) == UNION_TYPE)
4306 return initializer_constant_valid_p_1 (src, endtype, cache);
4308 break;
4310 case POINTER_PLUS_EXPR:
4311 case PLUS_EXPR:
4312 /* Any valid floating-point constants will have been folded by now;
4313 with -frounding-math we hit this with addition of two constants. */
4314 if (TREE_CODE (endtype) == REAL_TYPE)
4315 return NULL_TREE;
4316 if (cache && cache[0] == value)
4317 return cache[1];
4318 if (! INTEGRAL_TYPE_P (endtype)
4319 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4321 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4322 tree valid0
4323 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4324 endtype, ncache);
4325 tree valid1
4326 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4327 endtype, ncache + 2);
4328 /* If either term is absolute, use the other term's relocation. */
4329 if (valid0 == null_pointer_node)
4330 ret = valid1;
4331 else if (valid1 == null_pointer_node)
4332 ret = valid0;
4333 /* Support narrowing pointer differences. */
4334 else
4335 ret = narrowing_initializer_constant_valid_p (value, endtype,
4336 ncache);
4338 else
4339 /* Support narrowing pointer differences. */
4340 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4341 if (cache)
4343 cache[0] = value;
4344 cache[1] = ret;
4346 return ret;
4348 case MINUS_EXPR:
4349 if (TREE_CODE (endtype) == REAL_TYPE)
4350 return NULL_TREE;
4351 if (cache && cache[0] == value)
4352 return cache[1];
4353 if (! INTEGRAL_TYPE_P (endtype)
4354 || TYPE_PRECISION (endtype) >= TYPE_PRECISION (TREE_TYPE (value)))
4356 tree ncache[4] = { NULL_TREE, NULL_TREE, NULL_TREE, NULL_TREE };
4357 tree valid0
4358 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 0),
4359 endtype, ncache);
4360 tree valid1
4361 = initializer_constant_valid_p_1 (TREE_OPERAND (value, 1),
4362 endtype, ncache + 2);
4363 /* Win if second argument is absolute. */
4364 if (valid1 == null_pointer_node)
4365 ret = valid0;
4366 /* Win if both arguments have the same relocation.
4367 Then the value is absolute. */
4368 else if (valid0 == valid1 && valid0 != 0)
4369 ret = null_pointer_node;
4370 /* Since GCC guarantees that string constants are unique in the
4371 generated code, a subtraction between two copies of the same
4372 constant string is absolute. */
4373 else if (valid0 && TREE_CODE (valid0) == STRING_CST
4374 && valid1 && TREE_CODE (valid1) == STRING_CST
4375 && operand_equal_p (valid0, valid1, 1))
4376 ret = null_pointer_node;
4377 /* Support narrowing differences. */
4378 else
4379 ret = narrowing_initializer_constant_valid_p (value, endtype,
4380 ncache);
4382 else
4383 /* Support narrowing differences. */
4384 ret = narrowing_initializer_constant_valid_p (value, endtype, NULL);
4385 if (cache)
4387 cache[0] = value;
4388 cache[1] = ret;
4390 return ret;
4392 default:
4393 break;
4396 return NULL_TREE;
4399 /* Return nonzero if VALUE is a valid constant-valued expression
4400 for use in initializing a static variable; one that can be an
4401 element of a "constant" initializer.
4403 Return null_pointer_node if the value is absolute;
4404 if it is relocatable, return the variable that determines the relocation.
4405 We assume that VALUE has been folded as much as possible;
4406 therefore, we do not need to check for such things as
4407 arithmetic-combinations of integers. */
4408 tree
4409 initializer_constant_valid_p (tree value, tree endtype)
4411 return initializer_constant_valid_p_1 (value, endtype, NULL);
4414 /* Return true if VALUE is a valid constant-valued expression
4415 for use in initializing a static bit-field; one that can be
4416 an element of a "constant" initializer. */
4418 bool
4419 initializer_constant_valid_for_bitfield_p (tree value)
4421 /* For bitfields we support integer constants or possibly nested aggregates
4422 of such. */
4423 switch (TREE_CODE (value))
4425 case CONSTRUCTOR:
4427 unsigned HOST_WIDE_INT idx;
4428 tree elt;
4430 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4431 if (!initializer_constant_valid_for_bitfield_p (elt))
4432 return false;
4433 return true;
4436 case INTEGER_CST:
4437 case REAL_CST:
4438 return true;
4440 case VIEW_CONVERT_EXPR:
4441 case NON_LVALUE_EXPR:
4442 return
4443 initializer_constant_valid_for_bitfield_p (TREE_OPERAND (value, 0));
4445 default:
4446 break;
4449 return false;
4452 /* output_constructor outer state of relevance in recursive calls, typically
4453 for nested aggregate bitfields. */
4455 typedef struct {
4456 unsigned int bit_offset; /* current position in ... */
4457 int byte; /* ... the outer byte buffer. */
4458 } oc_outer_state;
4460 static unsigned HOST_WIDE_INT
4461 output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int,
4462 oc_outer_state *);
4464 /* Output assembler code for constant EXP to FILE, with no label.
4465 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4466 Assumes output_addressed_constants has been done on EXP already.
4468 Generate exactly SIZE bytes of assembler data, padding at the end
4469 with zeros if necessary. SIZE must always be specified.
4471 SIZE is important for structure constructors,
4472 since trailing members may have been omitted from the constructor.
4473 It is also important for initialization of arrays from string constants
4474 since the full length of the string constant might not be wanted.
4475 It is also needed for initialization of unions, where the initializer's
4476 type is just one member, and that may not be as long as the union.
4478 There a case in which we would fail to output exactly SIZE bytes:
4479 for a structure constructor that wants to produce more than SIZE bytes.
4480 But such constructors will never be generated for any possible input.
4482 ALIGN is the alignment of the data in bits. */
4484 void
4485 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align)
4487 enum tree_code code;
4488 unsigned HOST_WIDE_INT thissize;
4490 if (size == 0 || flag_syntax_only)
4491 return;
4493 /* See if we're trying to initialize a pointer in a non-default mode
4494 to the address of some declaration somewhere. If the target says
4495 the mode is valid for pointers, assume the target has a way of
4496 resolving it. */
4497 if (TREE_CODE (exp) == NOP_EXPR
4498 && POINTER_TYPE_P (TREE_TYPE (exp))
4499 && targetm.addr_space.valid_pointer_mode
4500 (TYPE_MODE (TREE_TYPE (exp)),
4501 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4503 tree saved_type = TREE_TYPE (exp);
4505 /* Peel off any intermediate conversions-to-pointer for valid
4506 pointer modes. */
4507 while (TREE_CODE (exp) == NOP_EXPR
4508 && POINTER_TYPE_P (TREE_TYPE (exp))
4509 && targetm.addr_space.valid_pointer_mode
4510 (TYPE_MODE (TREE_TYPE (exp)),
4511 TYPE_ADDR_SPACE (TREE_TYPE (TREE_TYPE (exp)))))
4512 exp = TREE_OPERAND (exp, 0);
4514 /* If what we're left with is the address of something, we can
4515 convert the address to the final type and output it that
4516 way. */
4517 if (TREE_CODE (exp) == ADDR_EXPR)
4518 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4519 /* Likewise for constant ints. */
4520 else if (TREE_CODE (exp) == INTEGER_CST)
4521 exp = build_int_cst_wide (saved_type, TREE_INT_CST_LOW (exp),
4522 TREE_INT_CST_HIGH (exp));
4526 /* Eliminate any conversions since we'll be outputting the underlying
4527 constant. */
4528 while (CONVERT_EXPR_P (exp)
4529 || TREE_CODE (exp) == NON_LVALUE_EXPR
4530 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4532 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4533 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4535 /* Make sure eliminating the conversion is really a no-op, except with
4536 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4537 union types to allow for Ada unchecked unions. */
4538 if (type_size > op_size
4539 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4540 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4541 /* Keep the conversion. */
4542 break;
4543 else
4544 exp = TREE_OPERAND (exp, 0);
4547 code = TREE_CODE (TREE_TYPE (exp));
4548 thissize = int_size_in_bytes (TREE_TYPE (exp));
4550 /* Allow a constructor with no elements for any data type.
4551 This means to fill the space with zeros. */
4552 if (TREE_CODE (exp) == CONSTRUCTOR
4553 && VEC_empty (constructor_elt, CONSTRUCTOR_ELTS (exp)))
4555 assemble_zeros (size);
4556 return;
4559 if (TREE_CODE (exp) == FDESC_EXPR)
4561 #ifdef ASM_OUTPUT_FDESC
4562 HOST_WIDE_INT part = tree_low_cst (TREE_OPERAND (exp, 1), 0);
4563 tree decl = TREE_OPERAND (exp, 0);
4564 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4565 #else
4566 gcc_unreachable ();
4567 #endif
4568 return;
4571 /* Now output the underlying data. If we've handling the padding, return.
4572 Otherwise, break and ensure SIZE is the size written. */
4573 switch (code)
4575 case BOOLEAN_TYPE:
4576 case INTEGER_TYPE:
4577 case ENUMERAL_TYPE:
4578 case POINTER_TYPE:
4579 case REFERENCE_TYPE:
4580 case OFFSET_TYPE:
4581 case FIXED_POINT_TYPE:
4582 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
4583 EXPAND_INITIALIZER),
4584 MIN (size, thissize), align, 0))
4585 error ("initializer for integer/fixed-point value is too complicated");
4586 break;
4588 case REAL_TYPE:
4589 if (TREE_CODE (exp) != REAL_CST)
4590 error ("initializer for floating value is not a floating constant");
4591 else
4592 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)), align);
4593 break;
4595 case COMPLEX_TYPE:
4596 output_constant (TREE_REALPART (exp), thissize / 2, align);
4597 output_constant (TREE_IMAGPART (exp), thissize / 2,
4598 min_align (align, BITS_PER_UNIT * (thissize / 2)));
4599 break;
4601 case ARRAY_TYPE:
4602 case VECTOR_TYPE:
4603 switch (TREE_CODE (exp))
4605 case CONSTRUCTOR:
4606 output_constructor (exp, size, align, NULL);
4607 return;
4608 case STRING_CST:
4609 thissize = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp),
4610 size);
4611 assemble_string (TREE_STRING_POINTER (exp), thissize);
4612 break;
4614 case VECTOR_CST:
4616 int elt_size;
4617 unsigned int i, nalign;
4618 enum machine_mode inner;
4620 inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4621 nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4623 elt_size = GET_MODE_SIZE (inner);
4625 output_constant (VECTOR_CST_ELT (exp, 0), elt_size, align);
4626 thissize = elt_size;
4627 for (i = 1; i < VECTOR_CST_NELTS (exp); ++i)
4629 output_constant (VECTOR_CST_ELT (exp, i), elt_size, nalign);
4630 thissize += elt_size;
4632 break;
4634 default:
4635 gcc_unreachable ();
4637 break;
4639 case RECORD_TYPE:
4640 case UNION_TYPE:
4641 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4642 output_constructor (exp, size, align, NULL);
4643 return;
4645 case ERROR_MARK:
4646 return;
4648 default:
4649 gcc_unreachable ();
4652 if (size > thissize)
4653 assemble_zeros (size - thissize);
4657 /* Subroutine of output_constructor, used for computing the size of
4658 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4659 type with an unspecified upper bound. */
4661 static unsigned HOST_WIDE_INT
4662 array_size_for_constructor (tree val)
4664 tree max_index;
4665 unsigned HOST_WIDE_INT cnt;
4666 tree index, value, tmp;
4667 double_int i;
4669 /* This code used to attempt to handle string constants that are not
4670 arrays of single-bytes, but nothing else does, so there's no point in
4671 doing it here. */
4672 if (TREE_CODE (val) == STRING_CST)
4673 return TREE_STRING_LENGTH (val);
4675 max_index = NULL_TREE;
4676 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
4678 if (TREE_CODE (index) == RANGE_EXPR)
4679 index = TREE_OPERAND (index, 1);
4680 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
4681 max_index = index;
4684 if (max_index == NULL_TREE)
4685 return 0;
4687 /* Compute the total number of array elements. */
4688 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
4689 i = double_int_sub (tree_to_double_int (max_index), tree_to_double_int (tmp));
4690 i = double_int_add (i, double_int_one);
4692 /* Multiply by the array element unit size to find number of bytes. */
4693 i = double_int_mul (i, tree_to_double_int
4694 (TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val)))));
4696 gcc_assert (double_int_fits_in_uhwi_p (i));
4697 return i.low;
4700 /* Other datastructures + helpers for output_constructor. */
4702 /* output_constructor local state to support interaction with helpers. */
4704 typedef struct {
4706 /* Received arguments. */
4707 tree exp; /* Constructor expression. */
4708 unsigned HOST_WIDE_INT size; /* # bytes to output - pad if necessary. */
4709 unsigned int align; /* Known initial alignment. */
4711 /* Constructor expression data. */
4712 tree type; /* Expression type. */
4713 tree field; /* Current field decl in a record. */
4714 tree min_index; /* Lower bound if specified for an array. */
4716 /* Output processing state. */
4717 HOST_WIDE_INT total_bytes; /* # bytes output so far / current position. */
4718 bool byte_buffer_in_use; /* Whether byte ... */
4719 int byte; /* ... contains part of a bitfield byte yet to
4720 be output. */
4722 int last_relative_index; /* Implicit or explicit index of the last
4723 array element output within a bitfield. */
4724 /* Current element. */
4725 tree val; /* Current element value. */
4726 tree index; /* Current element index. */
4728 } oc_local_state;
4730 /* Helper for output_constructor. From the current LOCAL state, output a
4731 RANGE_EXPR element. */
4733 static void
4734 output_constructor_array_range (oc_local_state *local)
4736 unsigned HOST_WIDE_INT fieldsize
4737 = int_size_in_bytes (TREE_TYPE (local->type));
4739 HOST_WIDE_INT lo_index
4740 = tree_low_cst (TREE_OPERAND (local->index, 0), 0);
4741 HOST_WIDE_INT hi_index
4742 = tree_low_cst (TREE_OPERAND (local->index, 1), 0);
4743 HOST_WIDE_INT index;
4745 unsigned int align2
4746 = min_align (local->align, fieldsize * BITS_PER_UNIT);
4748 for (index = lo_index; index <= hi_index; index++)
4750 /* Output the element's initial value. */
4751 if (local->val == NULL_TREE)
4752 assemble_zeros (fieldsize);
4753 else
4754 output_constant (local->val, fieldsize, align2);
4756 /* Count its size. */
4757 local->total_bytes += fieldsize;
4761 /* Helper for output_constructor. From the current LOCAL state, output a
4762 field element that is not true bitfield or part of an outer one. */
4764 static void
4765 output_constructor_regular_field (oc_local_state *local)
4767 /* Field size and position. Since this structure is static, we know the
4768 positions are constant. */
4769 unsigned HOST_WIDE_INT fieldsize;
4770 HOST_WIDE_INT fieldpos;
4772 unsigned int align2;
4774 if (local->index != NULL_TREE)
4776 double_int idx = double_int_sub (tree_to_double_int (local->index),
4777 tree_to_double_int (local->min_index));
4778 gcc_assert (double_int_fits_in_shwi_p (idx));
4779 fieldpos = (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (local->val)), 1)
4780 * idx.low);
4782 else if (local->field != NULL_TREE)
4783 fieldpos = int_byte_position (local->field);
4784 else
4785 fieldpos = 0;
4787 /* Output any buffered-up bit-fields preceding this element. */
4788 if (local->byte_buffer_in_use)
4790 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4791 local->total_bytes++;
4792 local->byte_buffer_in_use = false;
4795 /* Advance to offset of this element.
4796 Note no alignment needed in an array, since that is guaranteed
4797 if each element has the proper size. */
4798 if ((local->field != NULL_TREE || local->index != NULL_TREE)
4799 && fieldpos != local->total_bytes)
4801 gcc_assert (fieldpos >= local->total_bytes);
4802 assemble_zeros (fieldpos - local->total_bytes);
4803 local->total_bytes = fieldpos;
4806 /* Find the alignment of this element. */
4807 align2 = min_align (local->align, BITS_PER_UNIT * fieldpos);
4809 /* Determine size this element should occupy. */
4810 if (local->field)
4812 fieldsize = 0;
4814 /* If this is an array with an unspecified upper bound,
4815 the initializer determines the size. */
4816 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
4817 but we cannot do this until the deprecated support for
4818 initializing zero-length array members is removed. */
4819 if (TREE_CODE (TREE_TYPE (local->field)) == ARRAY_TYPE
4820 && TYPE_DOMAIN (TREE_TYPE (local->field))
4821 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (local->field))))
4823 fieldsize = array_size_for_constructor (local->val);
4824 /* Given a non-empty initialization, this field had
4825 better be last. */
4826 gcc_assert (!fieldsize || !DECL_CHAIN (local->field));
4828 else
4829 fieldsize = tree_low_cst (DECL_SIZE_UNIT (local->field), 1);
4831 else
4832 fieldsize = int_size_in_bytes (TREE_TYPE (local->type));
4834 /* Output the element's initial value. */
4835 if (local->val == NULL_TREE)
4836 assemble_zeros (fieldsize);
4837 else
4838 output_constant (local->val, fieldsize, align2);
4840 /* Count its size. */
4841 local->total_bytes += fieldsize;
4844 /* Helper for output_constructor. From the current LOCAL and OUTER states,
4845 output an element that is a true bitfield or part of an outer one. */
4847 static void
4848 output_constructor_bitfield (oc_local_state *local, oc_outer_state *outer)
4850 /* Bit size of this element. */
4851 HOST_WIDE_INT ebitsize
4852 = (local->field
4853 ? tree_low_cst (DECL_SIZE (local->field), 1)
4854 : tree_low_cst (TYPE_SIZE (TREE_TYPE (local->type)), 1));
4856 /* Relative index of this element if this is an array component. */
4857 HOST_WIDE_INT relative_index
4858 = (!local->field
4859 ? (local->index
4860 ? (tree_low_cst (local->index, 0)
4861 - tree_low_cst (local->min_index, 0))
4862 : local->last_relative_index + 1)
4863 : 0);
4865 /* Bit position of this element from the start of the containing
4866 constructor. */
4867 HOST_WIDE_INT constructor_relative_ebitpos
4868 = (local->field
4869 ? int_bit_position (local->field)
4870 : ebitsize * relative_index);
4872 /* Bit position of this element from the start of a possibly ongoing
4873 outer byte buffer. */
4874 HOST_WIDE_INT byte_relative_ebitpos
4875 = ((outer ? outer->bit_offset : 0) + constructor_relative_ebitpos);
4877 /* From the start of a possibly ongoing outer byte buffer, offsets to
4878 the first bit of this element and to the first bit past the end of
4879 this element. */
4880 HOST_WIDE_INT next_offset = byte_relative_ebitpos;
4881 HOST_WIDE_INT end_offset = byte_relative_ebitpos + ebitsize;
4883 local->last_relative_index = relative_index;
4885 if (local->val == NULL_TREE)
4886 local->val = integer_zero_node;
4888 while (TREE_CODE (local->val) == VIEW_CONVERT_EXPR
4889 || TREE_CODE (local->val) == NON_LVALUE_EXPR)
4890 local->val = TREE_OPERAND (local->val, 0);
4892 if (TREE_CODE (local->val) != INTEGER_CST
4893 && TREE_CODE (local->val) != CONSTRUCTOR)
4895 error ("invalid initial value for member %qE", DECL_NAME (local->field));
4896 return;
4899 /* If this field does not start in this (or, next) byte,
4900 skip some bytes. */
4901 if (next_offset / BITS_PER_UNIT != local->total_bytes)
4903 /* Output remnant of any bit field in previous bytes. */
4904 if (local->byte_buffer_in_use)
4906 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4907 local->total_bytes++;
4908 local->byte_buffer_in_use = false;
4911 /* If still not at proper byte, advance to there. */
4912 if (next_offset / BITS_PER_UNIT != local->total_bytes)
4914 gcc_assert (next_offset / BITS_PER_UNIT >= local->total_bytes);
4915 assemble_zeros (next_offset / BITS_PER_UNIT - local->total_bytes);
4916 local->total_bytes = next_offset / BITS_PER_UNIT;
4920 /* Set up the buffer if necessary. */
4921 if (!local->byte_buffer_in_use)
4923 local->byte = 0;
4924 if (ebitsize > 0)
4925 local->byte_buffer_in_use = true;
4928 /* If this is nested constructor, recurse passing the bit offset and the
4929 pending data, then retrieve the new pending data afterwards. */
4930 if (TREE_CODE (local->val) == CONSTRUCTOR)
4932 oc_outer_state output_state;
4934 output_state.bit_offset = next_offset % BITS_PER_UNIT;
4935 output_state.byte = local->byte;
4936 local->total_bytes
4937 += output_constructor (local->val, 0, 0, &output_state);
4938 local->byte = output_state.byte;
4939 return;
4942 /* Otherwise, we must split the element into pieces that fall within
4943 separate bytes, and combine each byte with previous or following
4944 bit-fields. */
4945 while (next_offset < end_offset)
4947 int this_time;
4948 int shift;
4949 HOST_WIDE_INT value;
4950 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
4951 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
4953 /* Advance from byte to byte
4954 within this element when necessary. */
4955 while (next_byte != local->total_bytes)
4957 assemble_integer (GEN_INT (local->byte), 1, BITS_PER_UNIT, 1);
4958 local->total_bytes++;
4959 local->byte = 0;
4962 /* Number of bits we can process at once
4963 (all part of the same byte). */
4964 this_time = MIN (end_offset - next_offset,
4965 BITS_PER_UNIT - next_bit);
4966 if (BYTES_BIG_ENDIAN)
4968 /* On big-endian machine, take the most significant bits
4969 first (of the bits that are significant)
4970 and put them into bytes from the most significant end. */
4971 shift = end_offset - next_offset - this_time;
4973 /* Don't try to take a bunch of bits that cross
4974 the word boundary in the INTEGER_CST. We can
4975 only select bits from the LOW or HIGH part
4976 not from both. */
4977 if (shift < HOST_BITS_PER_WIDE_INT
4978 && shift + this_time > HOST_BITS_PER_WIDE_INT)
4980 this_time = shift + this_time - HOST_BITS_PER_WIDE_INT;
4981 shift = HOST_BITS_PER_WIDE_INT;
4984 /* Now get the bits from the appropriate constant word. */
4985 if (shift < HOST_BITS_PER_WIDE_INT)
4986 value = TREE_INT_CST_LOW (local->val);
4987 else
4989 gcc_assert (shift < 2 * HOST_BITS_PER_WIDE_INT);
4990 value = TREE_INT_CST_HIGH (local->val);
4991 shift -= HOST_BITS_PER_WIDE_INT;
4994 /* Get the result. This works only when:
4995 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
4996 local->byte |= (((value >> shift)
4997 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
4998 << (BITS_PER_UNIT - this_time - next_bit));
5000 else
5002 /* On little-endian machines,
5003 take first the least significant bits of the value
5004 and pack them starting at the least significant
5005 bits of the bytes. */
5006 shift = next_offset - byte_relative_ebitpos;
5008 /* Don't try to take a bunch of bits that cross
5009 the word boundary in the INTEGER_CST. We can
5010 only select bits from the LOW or HIGH part
5011 not from both. */
5012 if (shift < HOST_BITS_PER_WIDE_INT
5013 && shift + this_time > HOST_BITS_PER_WIDE_INT)
5014 this_time = (HOST_BITS_PER_WIDE_INT - shift);
5016 /* Now get the bits from the appropriate constant word. */
5017 if (shift < HOST_BITS_PER_WIDE_INT)
5018 value = TREE_INT_CST_LOW (local->val);
5019 else
5021 gcc_assert (shift < 2 * HOST_BITS_PER_WIDE_INT);
5022 value = TREE_INT_CST_HIGH (local->val);
5023 shift -= HOST_BITS_PER_WIDE_INT;
5026 /* Get the result. This works only when:
5027 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
5028 local->byte |= (((value >> shift)
5029 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
5030 << next_bit);
5033 next_offset += this_time;
5034 local->byte_buffer_in_use = true;
5038 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
5039 Generate at least SIZE bytes, padding if necessary. OUTER designates the
5040 caller output state of relevance in recursive invocations. */
5042 static unsigned HOST_WIDE_INT
5043 output_constructor (tree exp, unsigned HOST_WIDE_INT size,
5044 unsigned int align, oc_outer_state * outer)
5046 unsigned HOST_WIDE_INT cnt;
5047 constructor_elt *ce;
5049 oc_local_state local;
5051 /* Setup our local state to communicate with helpers. */
5052 local.exp = exp;
5053 local.size = size;
5054 local.align = align;
5056 local.total_bytes = 0;
5057 local.byte_buffer_in_use = outer != NULL;
5058 local.byte = outer ? outer->byte : 0;
5060 local.type = TREE_TYPE (exp);
5062 local.last_relative_index = -1;
5064 local.min_index = NULL_TREE;
5065 if (TREE_CODE (local.type) == ARRAY_TYPE
5066 && TYPE_DOMAIN (local.type) != NULL_TREE)
5067 local.min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (local.type));
5069 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
5071 /* As CE goes through the elements of the constant, FIELD goes through the
5072 structure fields if the constant is a structure. If the constant is a
5073 union, we override this by getting the field from the TREE_LIST element.
5074 But the constant could also be an array. Then FIELD is zero.
5076 There is always a maximum of one element in the chain LINK for unions
5077 (even if the initializer in a source program incorrectly contains
5078 more one). */
5080 local.field = NULL_TREE;
5081 if (TREE_CODE (local.type) == RECORD_TYPE)
5082 local.field = TYPE_FIELDS (local.type);
5084 for (cnt = 0;
5085 VEC_iterate (constructor_elt, CONSTRUCTOR_ELTS (exp), cnt, ce);
5086 cnt++, local.field = local.field ? DECL_CHAIN (local.field) : 0)
5088 local.val = ce->value;
5089 local.index = NULL_TREE;
5091 /* The element in a union constructor specifies the proper field
5092 or index. */
5093 if (RECORD_OR_UNION_TYPE_P (local.type) && ce->index != NULL_TREE)
5094 local.field = ce->index;
5096 else if (TREE_CODE (local.type) == ARRAY_TYPE)
5097 local.index = ce->index;
5099 if (local.field && flag_verbose_asm)
5100 fprintf (asm_out_file, "%s %s:\n",
5101 ASM_COMMENT_START,
5102 DECL_NAME (local.field)
5103 ? IDENTIFIER_POINTER (DECL_NAME (local.field))
5104 : "<anonymous>");
5106 /* Eliminate the marker that makes a cast not be an lvalue. */
5107 if (local.val != NULL_TREE)
5108 STRIP_NOPS (local.val);
5110 /* Output the current element, using the appropriate helper ... */
5112 /* For an array slice not part of an outer bitfield. */
5113 if (!outer
5114 && local.index != NULL_TREE
5115 && TREE_CODE (local.index) == RANGE_EXPR)
5116 output_constructor_array_range (&local);
5118 /* For a field that is neither a true bitfield nor part of an outer one,
5119 known to be at least byte aligned and multiple-of-bytes long. */
5120 else if (!outer
5121 && (local.field == NULL_TREE
5122 || !CONSTRUCTOR_BITFIELD_P (local.field)))
5123 output_constructor_regular_field (&local);
5125 /* For a true bitfield or part of an outer one. Only INTEGER_CSTs are
5126 supported for scalar fields, so we may need to convert first. */
5127 else
5129 if (TREE_CODE (local.val) == REAL_CST)
5130 local.val
5131 = fold_unary (VIEW_CONVERT_EXPR,
5132 build_nonstandard_integer_type
5133 (TYPE_PRECISION (TREE_TYPE (local.val)), 0),
5134 local.val);
5135 output_constructor_bitfield (&local, outer);
5139 /* If we are not at toplevel, save the pending data for our caller.
5140 Otherwise output the pending data and padding zeros as needed. */
5141 if (outer)
5142 outer->byte = local.byte;
5143 else
5145 if (local.byte_buffer_in_use)
5147 assemble_integer (GEN_INT (local.byte), 1, BITS_PER_UNIT, 1);
5148 local.total_bytes++;
5151 if ((unsigned HOST_WIDE_INT)local.total_bytes < local.size)
5153 assemble_zeros (local.size - local.total_bytes);
5154 local.total_bytes = local.size;
5158 return local.total_bytes;
5161 /* Mark DECL as weak. */
5163 static void
5164 mark_weak (tree decl)
5166 DECL_WEAK (decl) = 1;
5168 if (DECL_RTL_SET_P (decl)
5169 && MEM_P (DECL_RTL (decl))
5170 && XEXP (DECL_RTL (decl), 0)
5171 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
5172 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
5175 /* Merge weak status between NEWDECL and OLDDECL. */
5177 void
5178 merge_weak (tree newdecl, tree olddecl)
5180 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
5182 if (DECL_WEAK (newdecl) && TARGET_SUPPORTS_WEAK)
5184 tree *pwd;
5185 /* We put the NEWDECL on the weak_decls list at some point
5186 and OLDDECL as well. Keep just OLDDECL on the list. */
5187 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
5188 if (TREE_VALUE (*pwd) == newdecl)
5190 *pwd = TREE_CHAIN (*pwd);
5191 break;
5194 return;
5197 if (DECL_WEAK (newdecl))
5199 tree wd;
5201 /* NEWDECL is weak, but OLDDECL is not. */
5203 /* If we already output the OLDDECL, we're in trouble; we can't
5204 go back and make it weak. This should never happen in
5205 unit-at-a-time compilation. */
5206 gcc_assert (!TREE_ASM_WRITTEN (olddecl));
5208 /* If we've already generated rtl referencing OLDDECL, we may
5209 have done so in a way that will not function properly with
5210 a weak symbol. Again in unit-at-a-time this should be
5211 impossible. */
5212 gcc_assert (!TREE_USED (olddecl)
5213 || !TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)));
5215 if (TARGET_SUPPORTS_WEAK)
5217 /* We put the NEWDECL on the weak_decls list at some point.
5218 Replace it with the OLDDECL. */
5219 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
5220 if (TREE_VALUE (wd) == newdecl)
5222 TREE_VALUE (wd) = olddecl;
5223 break;
5225 /* We may not find the entry on the list. If NEWDECL is a
5226 weak alias, then we will have already called
5227 globalize_decl to remove the entry; in that case, we do
5228 not need to do anything. */
5231 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
5232 mark_weak (olddecl);
5234 else
5235 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
5236 weak. Just update NEWDECL to indicate that it's weak too. */
5237 mark_weak (newdecl);
5240 /* Declare DECL to be a weak symbol. */
5242 void
5243 declare_weak (tree decl)
5245 gcc_assert (TREE_CODE (decl) != FUNCTION_DECL || !TREE_ASM_WRITTEN (decl));
5246 if (! TREE_PUBLIC (decl))
5247 error ("weak declaration of %q+D must be public", decl);
5248 else if (!TARGET_SUPPORTS_WEAK)
5249 warning (0, "weak declaration of %q+D not supported", decl);
5251 mark_weak (decl);
5252 if (!lookup_attribute ("weak", DECL_ATTRIBUTES (decl)))
5253 DECL_ATTRIBUTES (decl)
5254 = tree_cons (get_identifier ("weak"), NULL, DECL_ATTRIBUTES (decl));
5257 static void
5258 weak_finish_1 (tree decl)
5260 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
5261 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5262 #endif
5264 if (! TREE_USED (decl))
5265 return;
5267 #ifdef ASM_WEAKEN_DECL
5268 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
5269 #else
5270 #ifdef ASM_WEAKEN_LABEL
5271 ASM_WEAKEN_LABEL (asm_out_file, name);
5272 #else
5273 #ifdef ASM_OUTPUT_WEAK_ALIAS
5275 static bool warn_once = 0;
5276 if (! warn_once)
5278 warning (0, "only weak aliases are supported in this configuration");
5279 warn_once = 1;
5281 return;
5283 #endif
5284 #endif
5285 #endif
5288 /* Fiven an assembly name, find the decl it is associated with. */
5289 static tree
5290 find_decl (tree target)
5292 symtab_node node = symtab_node_for_asm (target);
5293 if (node)
5294 return node->symbol.decl;
5295 return NULL_TREE;
5298 /* This TREE_LIST contains weakref targets. */
5300 static GTY(()) tree weakref_targets;
5302 /* Emit any pending weak declarations. */
5304 void
5305 weak_finish (void)
5307 tree t;
5309 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5311 tree alias_decl = TREE_PURPOSE (t);
5312 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5314 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5315 /* Remove alias_decl from the weak list, but leave entries for
5316 the target alone. */
5317 target = NULL_TREE;
5318 #ifndef ASM_OUTPUT_WEAKREF
5319 else if (! TREE_SYMBOL_REFERENCED (target))
5321 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5322 defined, otherwise we and weak_finish_1 would use
5323 different macros. */
5324 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5325 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5326 # else
5327 tree decl = find_decl (target);
5329 if (! decl)
5331 decl = build_decl (DECL_SOURCE_LOCATION (alias_decl),
5332 TREE_CODE (alias_decl), target,
5333 TREE_TYPE (alias_decl));
5335 DECL_EXTERNAL (decl) = 1;
5336 TREE_PUBLIC (decl) = 1;
5337 DECL_ARTIFICIAL (decl) = 1;
5338 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5339 TREE_USED (decl) = 1;
5342 weak_finish_1 (decl);
5343 # endif
5345 #endif
5348 tree *p;
5349 tree t2;
5351 /* Remove the alias and the target from the pending weak list
5352 so that we do not emit any .weak directives for the former,
5353 nor multiple .weak directives for the latter. */
5354 for (p = &weak_decls; (t2 = *p) ; )
5356 if (TREE_VALUE (t2) == alias_decl
5357 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5358 *p = TREE_CHAIN (t2);
5359 else
5360 p = &TREE_CHAIN (t2);
5363 /* Remove other weakrefs to the same target, to speed things up. */
5364 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5366 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5367 *p = TREE_CHAIN (t2);
5368 else
5369 p = &TREE_CHAIN (t2);
5374 for (t = weak_decls; t; t = TREE_CHAIN (t))
5376 tree decl = TREE_VALUE (t);
5378 weak_finish_1 (decl);
5382 /* Emit the assembly bits to indicate that DECL is globally visible. */
5384 static void
5385 globalize_decl (tree decl)
5388 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5389 if (DECL_WEAK (decl))
5391 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5392 tree *p, t;
5394 #ifdef ASM_WEAKEN_DECL
5395 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5396 #else
5397 ASM_WEAKEN_LABEL (asm_out_file, name);
5398 #endif
5400 /* Remove this function from the pending weak list so that
5401 we do not emit multiple .weak directives for it. */
5402 for (p = &weak_decls; (t = *p) ; )
5404 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5405 *p = TREE_CHAIN (t);
5406 else
5407 p = &TREE_CHAIN (t);
5410 /* Remove weakrefs to the same target from the pending weakref
5411 list, for the same reason. */
5412 for (p = &weakref_targets; (t = *p) ; )
5414 if (DECL_ASSEMBLER_NAME (decl)
5415 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5416 *p = TREE_CHAIN (t);
5417 else
5418 p = &TREE_CHAIN (t);
5421 return;
5423 #endif
5425 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5428 VEC(alias_pair,gc) *alias_pairs;
5430 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5431 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5432 tree node is DECL to have the value of the tree node TARGET. */
5434 static void
5435 do_assemble_alias (tree decl, tree target)
5437 /* Emulated TLS had better not get this var. */
5438 gcc_assert(!(!targetm.have_tls
5439 && TREE_CODE (decl) == VAR_DECL
5440 && DECL_THREAD_LOCAL_P (decl)));
5442 if (TREE_ASM_WRITTEN (decl))
5443 return;
5445 /* We must force creation of DECL_RTL for debug info generation, even though
5446 we don't use it here. */
5447 make_decl_rtl (decl);
5449 TREE_ASM_WRITTEN (decl) = 1;
5450 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5452 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5454 ultimate_transparent_alias_target (&target);
5456 if (!TREE_SYMBOL_REFERENCED (target))
5457 weakref_targets = tree_cons (decl, target, weakref_targets);
5459 #ifdef ASM_OUTPUT_WEAKREF
5460 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5461 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5462 IDENTIFIER_POINTER (target));
5463 #else
5464 if (!TARGET_SUPPORTS_WEAK)
5466 error_at (DECL_SOURCE_LOCATION (decl),
5467 "weakref is not supported in this configuration");
5468 return;
5470 #endif
5471 return;
5474 #ifdef ASM_OUTPUT_DEF
5475 /* Make name accessible from other files, if appropriate. */
5477 if (TREE_PUBLIC (decl))
5479 globalize_decl (decl);
5480 maybe_assemble_visibility (decl);
5482 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5484 #if defined (ASM_OUTPUT_TYPE_DIRECTIVE) && HAVE_GNU_INDIRECT_FUNCTION
5485 ASM_OUTPUT_TYPE_DIRECTIVE
5486 (asm_out_file, IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5487 IFUNC_ASM_TYPE);
5488 #else
5489 error_at (DECL_SOURCE_LOCATION (decl),
5490 "ifunc is not supported in this configuration");
5491 #endif
5494 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5495 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5496 # else
5497 ASM_OUTPUT_DEF (asm_out_file,
5498 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5499 IDENTIFIER_POINTER (target));
5500 # endif
5501 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5503 const char *name;
5504 tree *p, t;
5506 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5507 # ifdef ASM_WEAKEN_DECL
5508 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5509 # else
5510 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5511 # endif
5512 /* Remove this function from the pending weak list so that
5513 we do not emit multiple .weak directives for it. */
5514 for (p = &weak_decls; (t = *p) ; )
5515 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5516 *p = TREE_CHAIN (t);
5517 else
5518 p = &TREE_CHAIN (t);
5520 /* Remove weakrefs to the same target from the pending weakref
5521 list, for the same reason. */
5522 for (p = &weakref_targets; (t = *p) ; )
5524 if (DECL_ASSEMBLER_NAME (decl)
5525 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5526 *p = TREE_CHAIN (t);
5527 else
5528 p = &TREE_CHAIN (t);
5531 #endif
5535 /* Allocate and construct a symbol alias set. */
5537 static symbol_alias_set_t *
5538 symbol_alias_set_create (void)
5540 return pointer_set_create ();
5543 /* Destruct and free a symbol alias set. */
5545 void
5546 symbol_alias_set_destroy (symbol_alias_set_t *aset)
5548 pointer_set_destroy (aset);
5551 /* Test if a symbol alias set contains a given name. */
5554 symbol_alias_set_contains (const symbol_alias_set_t *aset, tree t)
5556 /* We accept either a DECL or an IDENTIFIER directly. */
5557 if (TREE_CODE (t) != IDENTIFIER_NODE)
5558 t = DECL_ASSEMBLER_NAME (t);
5559 t = targetm.asm_out.mangle_assembler_name (IDENTIFIER_POINTER (t));
5560 return pointer_set_contains (aset, t);
5563 /* Enter a new name into a symbol alias set. */
5565 static int
5566 symbol_alias_set_insert (symbol_alias_set_t *aset, tree t)
5568 /* We accept either a DECL or an IDENTIFIER directly. */
5569 if (TREE_CODE (t) != IDENTIFIER_NODE)
5570 t = DECL_ASSEMBLER_NAME (t);
5571 t = targetm.asm_out.mangle_assembler_name (IDENTIFIER_POINTER (t));
5572 return pointer_set_insert (aset, t);
5575 /* IN_SET_P is a predicate function assuming to be taken
5576 alias_pair->decl, alias_pair->target and DATA arguments.
5578 Compute set of aliases by including everything where TRIVIALLY_VISIBLE
5579 predeicate is true and propagate across aliases such that when
5580 alias DECL is included, its TARGET is included too. */
5582 static symbol_alias_set_t *
5583 propagate_aliases_forward (bool (*in_set_p)
5584 (tree decl, tree target, void *data),
5585 void *data)
5587 symbol_alias_set_t *set;
5588 unsigned i;
5589 alias_pair *p;
5590 bool changed;
5592 set = symbol_alias_set_create ();
5593 for (i = 0; VEC_iterate (alias_pair, alias_pairs, i, p); ++i)
5594 if (in_set_p (p->decl, p->target, data))
5595 symbol_alias_set_insert (set, p->decl);
5598 changed = false;
5599 for (i = 0; VEC_iterate (alias_pair, alias_pairs, i, p); ++i)
5600 if (symbol_alias_set_contains (set, p->decl)
5601 && !symbol_alias_set_insert (set, p->target))
5602 changed = true;
5604 while (changed);
5606 return set;
5609 /* Like propagate_aliases_forward but do backward propagation. */
5611 symbol_alias_set_t *
5612 propagate_aliases_backward (bool (*in_set_p)
5613 (tree decl, tree target, void *data),
5614 void *data)
5616 symbol_alias_set_t *set;
5617 unsigned i;
5618 alias_pair *p;
5619 bool changed;
5621 /* We have to compute the set of set nodes including aliases
5622 themselves. */
5623 set = symbol_alias_set_create ();
5624 for (i = 0; VEC_iterate (alias_pair, alias_pairs, i, p); ++i)
5625 if (in_set_p (p->decl, p->target, data))
5626 symbol_alias_set_insert (set, p->target);
5629 changed = false;
5630 for (i = 0; VEC_iterate (alias_pair, alias_pairs, i, p); ++i)
5631 if (symbol_alias_set_contains (set, p->target)
5632 && !symbol_alias_set_insert (set, p->decl))
5633 changed = true;
5635 while (changed);
5637 return set;
5639 /* See if the alias is trivially visible. This means
5640 1) alias is expoerted from the unit or
5641 2) alias is used in the code.
5642 We assume that unused cgraph/varpool nodes has been
5643 removed.
5644 Used as callback for propagate_aliases. */
5646 static bool
5647 trivially_visible_alias (tree decl, tree target ATTRIBUTE_UNUSED,
5648 void *data ATTRIBUTE_UNUSED)
5650 struct cgraph_node *fnode = NULL;
5651 struct varpool_node *vnode = NULL;
5653 if (!TREE_PUBLIC (decl))
5655 if (TREE_CODE (decl) == FUNCTION_DECL)
5656 fnode = cgraph_get_node (decl);
5657 else
5658 vnode = varpool_get_node (decl);
5659 return vnode || fnode;
5661 else
5662 return true;
5665 /* See if the target of alias is defined in this unit.
5666 Used as callback for propagate_aliases. */
5668 static bool
5669 trivially_defined_alias (tree decl ATTRIBUTE_UNUSED,
5670 tree target,
5671 void *data ATTRIBUTE_UNUSED)
5673 struct cgraph_node *fnode = NULL;
5674 struct varpool_node *vnode = NULL;
5676 fnode = cgraph_node_for_asm (target);
5677 vnode = (fnode == NULL) ? varpool_node_for_asm (target) : NULL;
5678 return (fnode && fnode->analyzed) || (vnode && vnode->finalized);
5681 /* Remove the alias pairing for functions that are no longer in the call
5682 graph. */
5684 void
5685 remove_unreachable_alias_pairs (void)
5687 symbol_alias_set_t *visible;
5688 unsigned i;
5689 alias_pair *p;
5691 if (alias_pairs == NULL)
5692 return;
5694 /* We have to compute the set of visible nodes including aliases
5695 themselves. */
5696 visible = propagate_aliases_forward (trivially_visible_alias, NULL);
5698 for (i = 0; VEC_iterate (alias_pair, alias_pairs, i, p); )
5700 if (!DECL_EXTERNAL (p->decl)
5701 && !symbol_alias_set_contains (visible, p->decl))
5703 VEC_unordered_remove (alias_pair, alias_pairs, i);
5704 continue;
5707 i++;
5710 symbol_alias_set_destroy (visible);
5714 /* First pass of completing pending aliases. Make sure that cgraph knows
5715 which symbols will be required. */
5717 void
5718 finish_aliases_1 (void)
5720 symbol_alias_set_t *defined;
5721 unsigned i;
5722 alias_pair *p;
5724 if (alias_pairs == NULL)
5725 return;
5727 /* We have to compute the set of defined nodes including aliases
5728 themselves. */
5729 defined = propagate_aliases_backward (trivially_defined_alias, NULL);
5731 FOR_EACH_VEC_ELT (alias_pair, alias_pairs, i, p)
5733 tree target_decl;
5735 target_decl = find_decl (p->target);
5736 if (target_decl == NULL)
5738 if (symbol_alias_set_contains (defined, p->target))
5739 continue;
5741 if (! (p->emitted_diags & ALIAS_DIAG_TO_UNDEF)
5742 && ! lookup_attribute ("weakref", DECL_ATTRIBUTES (p->decl)))
5744 error ("%q+D aliased to undefined symbol %qE",
5745 p->decl, p->target);
5746 p->emitted_diags |= ALIAS_DIAG_TO_UNDEF;
5749 else if (! (p->emitted_diags & ALIAS_DIAG_TO_EXTERN)
5750 && DECL_EXTERNAL (target_decl)
5751 /* We use local aliases for C++ thunks to force the tailcall
5752 to bind locally. This is a hack - to keep it working do
5753 the following (which is not strictly correct). */
5754 && (! TREE_CODE (target_decl) == FUNCTION_DECL
5755 || ! DECL_VIRTUAL_P (target_decl))
5756 && ! lookup_attribute ("weakref", DECL_ATTRIBUTES (p->decl)))
5758 error ("%q+D aliased to external symbol %qE",
5759 p->decl, p->target);
5760 p->emitted_diags |= ALIAS_DIAG_TO_EXTERN;
5764 symbol_alias_set_destroy (defined);
5767 /* Second pass of completing pending aliases. Emit the actual assembly.
5768 This happens at the end of compilation and thus it is assured that the
5769 target symbol has been emitted. */
5771 void
5772 finish_aliases_2 (void)
5774 unsigned i;
5775 alias_pair *p;
5777 FOR_EACH_VEC_ELT (alias_pair, alias_pairs, i, p)
5778 do_assemble_alias (p->decl, p->target);
5780 VEC_truncate (alias_pair, alias_pairs, 0);
5783 /* Emit an assembler directive to make the symbol for DECL an alias to
5784 the symbol for TARGET. */
5786 void
5787 assemble_alias (tree decl, tree target)
5789 tree target_decl;
5791 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5793 tree alias = DECL_ASSEMBLER_NAME (decl);
5795 ultimate_transparent_alias_target (&target);
5797 if (alias == target)
5798 error ("weakref %q+D ultimately targets itself", decl);
5799 else
5801 #ifndef ASM_OUTPUT_WEAKREF
5802 IDENTIFIER_TRANSPARENT_ALIAS (alias) = 1;
5803 TREE_CHAIN (alias) = target;
5804 #endif
5806 if (TREE_PUBLIC (decl))
5807 error ("weakref %q+D must have static linkage", decl);
5809 else
5811 #if !defined (ASM_OUTPUT_DEF)
5812 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5813 error_at (DECL_SOURCE_LOCATION (decl),
5814 "alias definitions not supported in this configuration");
5815 return;
5816 # else
5817 if (!DECL_WEAK (decl))
5819 if (lookup_attribute ("ifunc", DECL_ATTRIBUTES (decl)))
5820 error_at (DECL_SOURCE_LOCATION (decl),
5821 "ifunc is not supported in this configuration");
5822 else
5823 error_at (DECL_SOURCE_LOCATION (decl),
5824 "only weak aliases are supported in this configuration");
5825 return;
5827 # endif
5828 #endif
5830 TREE_USED (decl) = 1;
5832 /* Allow aliases to aliases. */
5833 if (TREE_CODE (decl) == FUNCTION_DECL)
5834 cgraph_get_create_node (decl)->alias = true;
5835 else
5836 varpool_node (decl)->alias = true;
5838 /* If the target has already been emitted, we don't have to queue the
5839 alias. This saves a tad of memory. */
5840 if (cgraph_global_info_ready)
5841 target_decl = find_decl (target);
5842 else
5843 target_decl= NULL;
5844 if (target_decl && TREE_ASM_WRITTEN (target_decl))
5845 do_assemble_alias (decl, target);
5846 else
5848 alias_pair *p = VEC_safe_push (alias_pair, gc, alias_pairs, NULL);
5849 p->decl = decl;
5850 p->target = target;
5851 p->emitted_diags = ALIAS_DIAG_NONE;
5855 /* Record and output a table of translations from original function
5856 to its transaction aware clone. Note that tm_pure functions are
5857 considered to be their own clone. */
5859 static GTY((if_marked ("tree_map_marked_p"), param_is (struct tree_map)))
5860 htab_t tm_clone_hash;
5862 void
5863 record_tm_clone_pair (tree o, tree n)
5865 struct tree_map **slot, *h;
5867 if (tm_clone_hash == NULL)
5868 tm_clone_hash = htab_create_ggc (32, tree_map_hash, tree_map_eq, 0);
5870 h = ggc_alloc_tree_map ();
5871 h->hash = htab_hash_pointer (o);
5872 h->base.from = o;
5873 h->to = n;
5875 slot = (struct tree_map **)
5876 htab_find_slot_with_hash (tm_clone_hash, h, h->hash, INSERT);
5877 *slot = h;
5880 tree
5881 get_tm_clone_pair (tree o)
5883 if (tm_clone_hash)
5885 struct tree_map *h, in;
5887 in.base.from = o;
5888 in.hash = htab_hash_pointer (o);
5889 h = (struct tree_map *) htab_find_with_hash (tm_clone_hash,
5890 &in, in.hash);
5891 if (h)
5892 return h->to;
5894 return NULL_TREE;
5897 typedef struct tm_alias_pair
5899 unsigned int uid;
5900 tree from;
5901 tree to;
5902 } tm_alias_pair;
5904 DEF_VEC_O(tm_alias_pair);
5905 DEF_VEC_ALLOC_O(tm_alias_pair,heap);
5907 /* Helper function for finish_tm_clone_pairs. Dump a hash table entry
5908 into a VEC in INFO. */
5910 static int
5911 dump_tm_clone_to_vec (void **slot, void *info)
5913 struct tree_map *map = (struct tree_map *) *slot;
5914 VEC(tm_alias_pair,heap) **tm_alias_pairs
5915 = (VEC(tm_alias_pair, heap) **) info;
5916 tm_alias_pair *p;
5918 p = VEC_safe_push (tm_alias_pair, heap, *tm_alias_pairs, NULL);
5919 p->from = map->base.from;
5920 p->to = map->to;
5921 p->uid = DECL_UID (p->from);
5922 return 1;
5925 /* Dump the actual pairs to the .tm_clone_table section. */
5927 static void
5928 dump_tm_clone_pairs (VEC(tm_alias_pair,heap) *tm_alias_pairs)
5930 unsigned i;
5931 tm_alias_pair *p;
5932 bool switched = false;
5934 FOR_EACH_VEC_ELT (tm_alias_pair, tm_alias_pairs, i, p)
5936 tree src = p->from;
5937 tree dst = p->to;
5938 struct cgraph_node *src_n = cgraph_get_node (src);
5939 struct cgraph_node *dst_n = cgraph_get_node (dst);
5941 /* The function ipa_tm_create_version() marks the clone as needed if
5942 the original function was needed. But we also mark the clone as
5943 needed if we ever called the clone indirectly through
5944 TM_GETTMCLONE. If neither of these are true, we didn't generate
5945 a clone, and we didn't call it indirectly... no sense keeping it
5946 in the clone table. */
5947 if (!dst_n || !dst_n->analyzed)
5948 continue;
5950 /* This covers the case where we have optimized the original
5951 function away, and only access the transactional clone. */
5952 if (!src_n || !src_n->analyzed)
5953 continue;
5955 if (!switched)
5957 switch_to_section (targetm.asm_out.tm_clone_table_section ());
5958 assemble_align (POINTER_SIZE);
5959 switched = true;
5962 assemble_integer (XEXP (DECL_RTL (src), 0),
5963 POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
5964 assemble_integer (XEXP (DECL_RTL (dst), 0),
5965 POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
5969 /* Provide a default for the tm_clone_table section. */
5971 section *
5972 default_clone_table_section (void)
5974 return get_named_section (NULL, ".tm_clone_table", 3);
5977 /* Helper comparison function for qsorting by the DECL_UID stored in
5978 alias_pair->emitted_diags. */
5980 static int
5981 tm_alias_pair_cmp (const void *x, const void *y)
5983 const tm_alias_pair *p1 = (const tm_alias_pair *) x;
5984 const tm_alias_pair *p2 = (const tm_alias_pair *) y;
5985 if (p1->uid < p2->uid)
5986 return -1;
5987 if (p1->uid > p2->uid)
5988 return 1;
5989 return 0;
5992 void
5993 finish_tm_clone_pairs (void)
5995 VEC(tm_alias_pair,heap) *tm_alias_pairs = NULL;
5997 if (tm_clone_hash == NULL)
5998 return;
6000 /* We need a determenistic order for the .tm_clone_table, otherwise
6001 we will get bootstrap comparison failures, so dump the hash table
6002 to a vector, sort it, and dump the vector. */
6004 /* Dump the hashtable to a vector. */
6005 htab_traverse_noresize (tm_clone_hash, dump_tm_clone_to_vec,
6006 (void *) &tm_alias_pairs);
6007 /* Sort it. */
6008 VEC_qsort (tm_alias_pair, tm_alias_pairs, tm_alias_pair_cmp);
6010 /* Dump it. */
6011 dump_tm_clone_pairs (tm_alias_pairs);
6013 htab_delete (tm_clone_hash);
6014 tm_clone_hash = NULL;
6015 VEC_free (tm_alias_pair, heap, tm_alias_pairs);
6019 /* Emit an assembler directive to set symbol for DECL visibility to
6020 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
6022 void
6023 default_assemble_visibility (tree decl ATTRIBUTE_UNUSED,
6024 int vis ATTRIBUTE_UNUSED)
6026 #ifdef HAVE_GAS_HIDDEN
6027 static const char * const visibility_types[] = {
6028 NULL, "protected", "hidden", "internal"
6031 const char *name, *type;
6033 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
6034 type = visibility_types[vis];
6036 fprintf (asm_out_file, "\t.%s\t", type);
6037 assemble_name (asm_out_file, name);
6038 fprintf (asm_out_file, "\n");
6039 #else
6040 warning (OPT_Wattributes, "visibility attribute not supported "
6041 "in this configuration; ignored");
6042 #endif
6045 /* A helper function to call assemble_visibility when needed for a decl. */
6048 maybe_assemble_visibility (tree decl)
6050 enum symbol_visibility vis = DECL_VISIBILITY (decl);
6052 if (vis != VISIBILITY_DEFAULT)
6054 targetm.asm_out.assemble_visibility (decl, vis);
6055 return 1;
6057 else
6058 return 0;
6061 /* Returns 1 if the target configuration supports defining public symbols
6062 so that one of them will be chosen at link time instead of generating a
6063 multiply-defined symbol error, whether through the use of weak symbols or
6064 a target-specific mechanism for having duplicates discarded. */
6067 supports_one_only (void)
6069 if (SUPPORTS_ONE_ONLY)
6070 return 1;
6071 return TARGET_SUPPORTS_WEAK;
6074 /* Set up DECL as a public symbol that can be defined in multiple
6075 translation units without generating a linker error. */
6077 void
6078 make_decl_one_only (tree decl, tree comdat_group)
6080 gcc_assert (TREE_CODE (decl) == VAR_DECL
6081 || TREE_CODE (decl) == FUNCTION_DECL);
6083 TREE_PUBLIC (decl) = 1;
6085 if (SUPPORTS_ONE_ONLY)
6087 #ifdef MAKE_DECL_ONE_ONLY
6088 MAKE_DECL_ONE_ONLY (decl);
6089 #endif
6090 DECL_COMDAT_GROUP (decl) = comdat_group;
6092 else if (TREE_CODE (decl) == VAR_DECL
6093 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node))
6094 DECL_COMMON (decl) = 1;
6095 else
6097 gcc_assert (TARGET_SUPPORTS_WEAK);
6098 DECL_WEAK (decl) = 1;
6102 void
6103 init_varasm_once (void)
6105 section_htab = htab_create_ggc (31, section_entry_hash,
6106 section_entry_eq, NULL);
6107 object_block_htab = htab_create_ggc (31, object_block_entry_hash,
6108 object_block_entry_eq, NULL);
6109 const_desc_htab = htab_create_ggc (1009, const_desc_hash,
6110 const_desc_eq, NULL);
6112 const_alias_set = new_alias_set ();
6113 shared_constant_pool = create_constant_pool ();
6115 #ifdef TEXT_SECTION_ASM_OP
6116 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
6117 TEXT_SECTION_ASM_OP);
6118 #endif
6120 #ifdef DATA_SECTION_ASM_OP
6121 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
6122 DATA_SECTION_ASM_OP);
6123 #endif
6125 #ifdef SDATA_SECTION_ASM_OP
6126 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
6127 SDATA_SECTION_ASM_OP);
6128 #endif
6130 #ifdef READONLY_DATA_SECTION_ASM_OP
6131 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
6132 READONLY_DATA_SECTION_ASM_OP);
6133 #endif
6135 #ifdef CTORS_SECTION_ASM_OP
6136 ctors_section = get_unnamed_section (0, output_section_asm_op,
6137 CTORS_SECTION_ASM_OP);
6138 #endif
6140 #ifdef DTORS_SECTION_ASM_OP
6141 dtors_section = get_unnamed_section (0, output_section_asm_op,
6142 DTORS_SECTION_ASM_OP);
6143 #endif
6145 #ifdef BSS_SECTION_ASM_OP
6146 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6147 output_section_asm_op,
6148 BSS_SECTION_ASM_OP);
6149 #endif
6151 #ifdef SBSS_SECTION_ASM_OP
6152 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
6153 output_section_asm_op,
6154 SBSS_SECTION_ASM_OP);
6155 #endif
6157 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6158 | SECTION_COMMON, emit_tls_common);
6159 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6160 | SECTION_COMMON, emit_local);
6161 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
6162 | SECTION_COMMON, emit_common);
6164 #if defined ASM_OUTPUT_ALIGNED_BSS
6165 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
6166 emit_bss);
6167 #endif
6169 targetm.asm_out.init_sections ();
6171 if (readonly_data_section == NULL)
6172 readonly_data_section = text_section;
6175 enum tls_model
6176 decl_default_tls_model (const_tree decl)
6178 enum tls_model kind;
6179 bool is_local;
6181 is_local = targetm.binds_local_p (decl);
6182 if (!flag_shlib)
6184 if (is_local)
6185 kind = TLS_MODEL_LOCAL_EXEC;
6186 else
6187 kind = TLS_MODEL_INITIAL_EXEC;
6190 /* Local dynamic is inefficient when we're not combining the
6191 parts of the address. */
6192 else if (optimize && is_local)
6193 kind = TLS_MODEL_LOCAL_DYNAMIC;
6194 else
6195 kind = TLS_MODEL_GLOBAL_DYNAMIC;
6196 if (kind < flag_tls_default)
6197 kind = flag_tls_default;
6199 return kind;
6202 /* Select a set of attributes for section NAME based on the properties
6203 of DECL and whether or not RELOC indicates that DECL's initializer
6204 might contain runtime relocations.
6206 We make the section read-only and executable for a function decl,
6207 read-only for a const data decl, and writable for a non-const data decl. */
6209 unsigned int
6210 default_section_type_flags (tree decl, const char *name, int reloc)
6212 unsigned int flags;
6214 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
6215 flags = SECTION_CODE;
6216 else if (decl)
6218 enum section_category category
6219 = categorize_decl_for_section (decl, reloc);
6220 if (decl_readonly_section_1 (category))
6221 flags = 0;
6222 else if (category == SECCAT_DATA_REL_RO
6223 || category == SECCAT_DATA_REL_RO_LOCAL)
6224 flags = SECTION_WRITE | SECTION_RELRO;
6225 else
6226 flags = SECTION_WRITE;
6228 else
6230 flags = SECTION_WRITE;
6231 if (strcmp (name, ".data.rel.ro") == 0
6232 || strcmp (name, ".data.rel.ro.local") == 0)
6233 flags |= SECTION_RELRO;
6236 if (decl && DECL_ONE_ONLY (decl))
6237 flags |= SECTION_LINKONCE;
6239 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6240 flags |= SECTION_TLS | SECTION_WRITE;
6242 if (strcmp (name, ".bss") == 0
6243 || strncmp (name, ".bss.", 5) == 0
6244 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
6245 || strcmp (name, ".sbss") == 0
6246 || strncmp (name, ".sbss.", 6) == 0
6247 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
6248 flags |= SECTION_BSS;
6250 if (strcmp (name, ".tdata") == 0
6251 || strncmp (name, ".tdata.", 7) == 0
6252 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
6253 flags |= SECTION_TLS;
6255 if (strcmp (name, ".tbss") == 0
6256 || strncmp (name, ".tbss.", 6) == 0
6257 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
6258 flags |= SECTION_TLS | SECTION_BSS;
6260 /* These three sections have special ELF types. They are neither
6261 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
6262 want to print a section type (@progbits or @nobits). If someone
6263 is silly enough to emit code or TLS variables to one of these
6264 sections, then don't handle them specially. */
6265 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
6266 && (strcmp (name, ".init_array") == 0
6267 || strcmp (name, ".fini_array") == 0
6268 || strcmp (name, ".preinit_array") == 0))
6269 flags |= SECTION_NOTYPE;
6271 return flags;
6274 /* Return true if the target supports some form of global BSS,
6275 either through bss_noswitch_section, or by selecting a BSS
6276 section in TARGET_ASM_SELECT_SECTION. */
6278 bool
6279 have_global_bss_p (void)
6281 return bss_noswitch_section || targetm.have_switchable_bss_sections;
6284 /* Output assembly to switch to section NAME with attribute FLAGS.
6285 Four variants for common object file formats. */
6287 void
6288 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
6289 unsigned int flags ATTRIBUTE_UNUSED,
6290 tree decl ATTRIBUTE_UNUSED)
6292 /* Some object formats don't support named sections at all. The
6293 front-end should already have flagged this as an error. */
6294 gcc_unreachable ();
6297 #ifndef TLS_SECTION_ASM_FLAG
6298 #define TLS_SECTION_ASM_FLAG 'T'
6299 #endif
6301 void
6302 default_elf_asm_named_section (const char *name, unsigned int flags,
6303 tree decl ATTRIBUTE_UNUSED)
6305 char flagchars[10], *f = flagchars;
6307 /* If we have already declared this section, we can use an
6308 abbreviated form to switch back to it -- unless this section is
6309 part of a COMDAT groups, in which case GAS requires the full
6310 declaration every time. */
6311 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6312 && (flags & SECTION_DECLARED))
6314 fprintf (asm_out_file, "\t.section\t%s\n", name);
6315 return;
6318 if (!(flags & SECTION_DEBUG))
6319 *f++ = 'a';
6320 if (flags & SECTION_EXCLUDE)
6321 *f++ = 'e';
6322 if (flags & SECTION_WRITE)
6323 *f++ = 'w';
6324 if (flags & SECTION_CODE)
6325 *f++ = 'x';
6326 if (flags & SECTION_SMALL)
6327 *f++ = 's';
6328 if (flags & SECTION_MERGE)
6329 *f++ = 'M';
6330 if (flags & SECTION_STRINGS)
6331 *f++ = 'S';
6332 if (flags & SECTION_TLS)
6333 *f++ = TLS_SECTION_ASM_FLAG;
6334 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6335 *f++ = 'G';
6336 *f = '\0';
6338 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
6340 if (!(flags & SECTION_NOTYPE))
6342 const char *type;
6343 const char *format;
6345 if (flags & SECTION_BSS)
6346 type = "nobits";
6347 else
6348 type = "progbits";
6350 format = ",@%s";
6351 /* On platforms that use "@" as the assembly comment character,
6352 use "%" instead. */
6353 if (strcmp (ASM_COMMENT_START, "@") == 0)
6354 format = ",%%%s";
6355 fprintf (asm_out_file, format, type);
6357 if (flags & SECTION_ENTSIZE)
6358 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
6359 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
6361 if (TREE_CODE (decl) == IDENTIFIER_NODE)
6362 fprintf (asm_out_file, ",%s,comdat", IDENTIFIER_POINTER (decl));
6363 else
6364 fprintf (asm_out_file, ",%s,comdat",
6365 IDENTIFIER_POINTER (DECL_COMDAT_GROUP (decl)));
6369 putc ('\n', asm_out_file);
6372 void
6373 default_coff_asm_named_section (const char *name, unsigned int flags,
6374 tree decl ATTRIBUTE_UNUSED)
6376 char flagchars[8], *f = flagchars;
6378 if (flags & SECTION_WRITE)
6379 *f++ = 'w';
6380 if (flags & SECTION_CODE)
6381 *f++ = 'x';
6382 *f = '\0';
6384 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
6387 void
6388 default_pe_asm_named_section (const char *name, unsigned int flags,
6389 tree decl)
6391 default_coff_asm_named_section (name, flags, decl);
6393 if (flags & SECTION_LINKONCE)
6395 /* Functions may have been compiled at various levels of
6396 optimization so we can't use `same_size' here.
6397 Instead, have the linker pick one. */
6398 fprintf (asm_out_file, "\t.linkonce %s\n",
6399 (flags & SECTION_CODE ? "discard" : "same_size"));
6403 /* The lame default section selector. */
6405 section *
6406 default_select_section (tree decl, int reloc,
6407 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6409 if (DECL_P (decl))
6411 if (decl_readonly_section (decl, reloc))
6412 return readonly_data_section;
6414 else if (TREE_CODE (decl) == CONSTRUCTOR)
6416 if (! ((flag_pic && reloc)
6417 || !TREE_READONLY (decl)
6418 || TREE_SIDE_EFFECTS (decl)
6419 || !TREE_CONSTANT (decl)))
6420 return readonly_data_section;
6422 else if (TREE_CODE (decl) == STRING_CST)
6423 return readonly_data_section;
6424 else if (! (flag_pic && reloc))
6425 return readonly_data_section;
6427 return data_section;
6430 enum section_category
6431 categorize_decl_for_section (const_tree decl, int reloc)
6433 enum section_category ret;
6435 if (TREE_CODE (decl) == FUNCTION_DECL)
6436 return SECCAT_TEXT;
6437 else if (TREE_CODE (decl) == STRING_CST)
6439 if (flag_mudflap) /* or !flag_merge_constants */
6440 return SECCAT_RODATA;
6441 else
6442 return SECCAT_RODATA_MERGE_STR;
6444 else if (TREE_CODE (decl) == VAR_DECL)
6446 if (bss_initializer_p (decl))
6447 ret = SECCAT_BSS;
6448 else if (! TREE_READONLY (decl)
6449 || TREE_SIDE_EFFECTS (decl)
6450 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
6452 /* Here the reloc_rw_mask is not testing whether the section should
6453 be read-only or not, but whether the dynamic link will have to
6454 do something. If so, we wish to segregate the data in order to
6455 minimize cache misses inside the dynamic linker. */
6456 if (reloc & targetm.asm_out.reloc_rw_mask ())
6457 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
6458 else
6459 ret = SECCAT_DATA;
6461 else if (reloc & targetm.asm_out.reloc_rw_mask ())
6462 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
6463 else if (reloc || flag_merge_constants < 2)
6464 /* C and C++ don't allow different variables to share the same
6465 location. -fmerge-all-constants allows even that (at the
6466 expense of not conforming). */
6467 ret = SECCAT_RODATA;
6468 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
6469 ret = SECCAT_RODATA_MERGE_STR_INIT;
6470 else
6471 ret = SECCAT_RODATA_MERGE_CONST;
6473 else if (TREE_CODE (decl) == CONSTRUCTOR)
6475 if ((reloc & targetm.asm_out.reloc_rw_mask ())
6476 || TREE_SIDE_EFFECTS (decl)
6477 || ! TREE_CONSTANT (decl))
6478 ret = SECCAT_DATA;
6479 else
6480 ret = SECCAT_RODATA;
6482 else
6483 ret = SECCAT_RODATA;
6485 /* There are no read-only thread-local sections. */
6486 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6488 /* Note that this would be *just* SECCAT_BSS, except that there's
6489 no concept of a read-only thread-local-data section. */
6490 if (ret == SECCAT_BSS
6491 || (flag_zero_initialized_in_bss
6492 && initializer_zerop (DECL_INITIAL (decl))))
6493 ret = SECCAT_TBSS;
6494 else
6495 ret = SECCAT_TDATA;
6498 /* If the target uses small data sections, select it. */
6499 else if (targetm.in_small_data_p (decl))
6501 if (ret == SECCAT_BSS)
6502 ret = SECCAT_SBSS;
6503 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
6504 ret = SECCAT_SRODATA;
6505 else
6506 ret = SECCAT_SDATA;
6509 return ret;
6512 static bool
6513 decl_readonly_section_1 (enum section_category category)
6515 switch (category)
6517 case SECCAT_RODATA:
6518 case SECCAT_RODATA_MERGE_STR:
6519 case SECCAT_RODATA_MERGE_STR_INIT:
6520 case SECCAT_RODATA_MERGE_CONST:
6521 case SECCAT_SRODATA:
6522 return true;
6523 default:
6524 return false;
6528 bool
6529 decl_readonly_section (const_tree decl, int reloc)
6531 return decl_readonly_section_1 (categorize_decl_for_section (decl, reloc));
6534 /* Select a section based on the above categorization. */
6536 section *
6537 default_elf_select_section (tree decl, int reloc,
6538 unsigned HOST_WIDE_INT align)
6540 const char *sname;
6541 switch (categorize_decl_for_section (decl, reloc))
6543 case SECCAT_TEXT:
6544 /* We're not supposed to be called on FUNCTION_DECLs. */
6545 gcc_unreachable ();
6546 case SECCAT_RODATA:
6547 return readonly_data_section;
6548 case SECCAT_RODATA_MERGE_STR:
6549 return mergeable_string_section (decl, align, 0);
6550 case SECCAT_RODATA_MERGE_STR_INIT:
6551 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
6552 case SECCAT_RODATA_MERGE_CONST:
6553 return mergeable_constant_section (DECL_MODE (decl), align, 0);
6554 case SECCAT_SRODATA:
6555 sname = ".sdata2";
6556 break;
6557 case SECCAT_DATA:
6558 return data_section;
6559 case SECCAT_DATA_REL:
6560 sname = ".data.rel";
6561 break;
6562 case SECCAT_DATA_REL_LOCAL:
6563 sname = ".data.rel.local";
6564 break;
6565 case SECCAT_DATA_REL_RO:
6566 sname = ".data.rel.ro";
6567 break;
6568 case SECCAT_DATA_REL_RO_LOCAL:
6569 sname = ".data.rel.ro.local";
6570 break;
6571 case SECCAT_SDATA:
6572 sname = ".sdata";
6573 break;
6574 case SECCAT_TDATA:
6575 sname = ".tdata";
6576 break;
6577 case SECCAT_BSS:
6578 if (bss_section)
6579 return bss_section;
6580 sname = ".bss";
6581 break;
6582 case SECCAT_SBSS:
6583 sname = ".sbss";
6584 break;
6585 case SECCAT_TBSS:
6586 sname = ".tbss";
6587 break;
6588 default:
6589 gcc_unreachable ();
6592 if (!DECL_P (decl))
6593 decl = NULL_TREE;
6594 return get_named_section (decl, sname, reloc);
6597 /* Construct a unique section name based on the decl name and the
6598 categorization performed above. */
6600 void
6601 default_unique_section (tree decl, int reloc)
6603 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
6604 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
6605 const char *prefix, *name, *linkonce;
6606 char *string;
6608 switch (categorize_decl_for_section (decl, reloc))
6610 case SECCAT_TEXT:
6611 prefix = one_only ? ".t" : ".text";
6612 break;
6613 case SECCAT_RODATA:
6614 case SECCAT_RODATA_MERGE_STR:
6615 case SECCAT_RODATA_MERGE_STR_INIT:
6616 case SECCAT_RODATA_MERGE_CONST:
6617 prefix = one_only ? ".r" : ".rodata";
6618 break;
6619 case SECCAT_SRODATA:
6620 prefix = one_only ? ".s2" : ".sdata2";
6621 break;
6622 case SECCAT_DATA:
6623 prefix = one_only ? ".d" : ".data";
6624 break;
6625 case SECCAT_DATA_REL:
6626 prefix = one_only ? ".d.rel" : ".data.rel";
6627 break;
6628 case SECCAT_DATA_REL_LOCAL:
6629 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6630 break;
6631 case SECCAT_DATA_REL_RO:
6632 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6633 break;
6634 case SECCAT_DATA_REL_RO_LOCAL:
6635 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6636 break;
6637 case SECCAT_SDATA:
6638 prefix = one_only ? ".s" : ".sdata";
6639 break;
6640 case SECCAT_BSS:
6641 prefix = one_only ? ".b" : ".bss";
6642 break;
6643 case SECCAT_SBSS:
6644 prefix = one_only ? ".sb" : ".sbss";
6645 break;
6646 case SECCAT_TDATA:
6647 prefix = one_only ? ".td" : ".tdata";
6648 break;
6649 case SECCAT_TBSS:
6650 prefix = one_only ? ".tb" : ".tbss";
6651 break;
6652 default:
6653 gcc_unreachable ();
6656 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
6657 name = targetm.strip_name_encoding (name);
6659 /* If we're using one_only, then there needs to be a .gnu.linkonce
6660 prefix to the section name. */
6661 linkonce = one_only ? ".gnu.linkonce" : "";
6663 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6665 DECL_SECTION_NAME (decl) = build_string (strlen (string), string);
6668 /* Like compute_reloc_for_constant, except for an RTX. The return value
6669 is a mask for which bit 1 indicates a global relocation, and bit 0
6670 indicates a local relocation. */
6672 static int
6673 compute_reloc_for_rtx_1 (rtx *xp, void *data)
6675 int *preloc = (int *) data;
6676 rtx x = *xp;
6678 switch (GET_CODE (x))
6680 case SYMBOL_REF:
6681 *preloc |= SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6682 break;
6683 case LABEL_REF:
6684 *preloc |= 1;
6685 break;
6686 default:
6687 break;
6690 return 0;
6693 static int
6694 compute_reloc_for_rtx (rtx x)
6696 int reloc;
6698 switch (GET_CODE (x))
6700 case CONST:
6701 case SYMBOL_REF:
6702 case LABEL_REF:
6703 reloc = 0;
6704 for_each_rtx (&x, compute_reloc_for_rtx_1, &reloc);
6705 return reloc;
6707 default:
6708 return 0;
6712 section *
6713 default_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
6714 rtx x,
6715 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6717 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6718 return data_section;
6719 else
6720 return readonly_data_section;
6723 section *
6724 default_elf_select_rtx_section (enum machine_mode mode, rtx x,
6725 unsigned HOST_WIDE_INT align)
6727 int reloc = compute_reloc_for_rtx (x);
6729 /* ??? Handle small data here somehow. */
6731 if (reloc & targetm.asm_out.reloc_rw_mask ())
6733 if (reloc == 1)
6734 return get_named_section (NULL, ".data.rel.ro.local", 1);
6735 else
6736 return get_named_section (NULL, ".data.rel.ro", 3);
6739 return mergeable_constant_section (mode, align, 0);
6742 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6744 void
6745 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6747 rtx symbol;
6748 int flags;
6750 /* Careful not to prod global register variables. */
6751 if (!MEM_P (rtl))
6752 return;
6753 symbol = XEXP (rtl, 0);
6754 if (GET_CODE (symbol) != SYMBOL_REF)
6755 return;
6757 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6758 if (TREE_CODE (decl) == FUNCTION_DECL)
6759 flags |= SYMBOL_FLAG_FUNCTION;
6760 if (targetm.binds_local_p (decl))
6761 flags |= SYMBOL_FLAG_LOCAL;
6762 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
6763 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6764 else if (targetm.in_small_data_p (decl))
6765 flags |= SYMBOL_FLAG_SMALL;
6766 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6767 being PUBLIC, the thing *must* be defined in this translation unit.
6768 Prevent this buglet from being propagated into rtl code as well. */
6769 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6770 flags |= SYMBOL_FLAG_EXTERNAL;
6772 SYMBOL_REF_FLAGS (symbol) = flags;
6775 /* By default, we do nothing for encode_section_info, so we need not
6776 do anything but discard the '*' marker. */
6778 const char *
6779 default_strip_name_encoding (const char *str)
6781 return str + (*str == '*');
6784 #ifdef ASM_OUTPUT_DEF
6785 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6786 anchor relative to ".", the current section position. */
6788 void
6789 default_asm_output_anchor (rtx symbol)
6791 char buffer[100];
6793 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6794 SYMBOL_REF_BLOCK_OFFSET (symbol));
6795 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6797 #endif
6799 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6801 bool
6802 default_use_anchors_for_symbol_p (const_rtx symbol)
6804 section *sect;
6805 tree decl;
6807 /* Don't use anchors for mergeable sections. The linker might move
6808 the objects around. */
6809 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6810 if (sect->common.flags & SECTION_MERGE)
6811 return false;
6813 /* Don't use anchors for small data sections. The small data register
6814 acts as an anchor for such sections. */
6815 if (sect->common.flags & SECTION_SMALL)
6816 return false;
6818 decl = SYMBOL_REF_DECL (symbol);
6819 if (decl && DECL_P (decl))
6821 /* Don't use section anchors for decls that might be defined by
6822 other modules. */
6823 if (!targetm.binds_local_p (decl))
6824 return false;
6826 /* Don't use section anchors for decls that will be placed in a
6827 small data section. */
6828 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6829 one above. The problem is that we only use SECTION_SMALL for
6830 sections that should be marked as small in the section directive. */
6831 if (targetm.in_small_data_p (decl))
6832 return false;
6834 return true;
6837 /* Return true when RESOLUTION indicate that symbol will be bound to the
6838 definition provided by current .o file. */
6840 static bool
6841 resolution_to_local_definition_p (enum ld_plugin_symbol_resolution resolution)
6843 return (resolution == LDPR_PREVAILING_DEF
6844 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6845 || resolution == LDPR_PREVAILING_DEF_IRONLY);
6848 /* Return true when RESOLUTION indicate that symbol will be bound locally
6849 within current executable or DSO. */
6851 static bool
6852 resolution_local_p (enum ld_plugin_symbol_resolution resolution)
6854 return (resolution == LDPR_PREVAILING_DEF
6855 || resolution == LDPR_PREVAILING_DEF_IRONLY
6856 || resolution == LDPR_PREVAILING_DEF_IRONLY_EXP
6857 || resolution == LDPR_PREEMPTED_REG
6858 || resolution == LDPR_PREEMPTED_IR
6859 || resolution == LDPR_RESOLVED_IR
6860 || resolution == LDPR_RESOLVED_EXEC);
6863 /* Assume ELF-ish defaults, since that's pretty much the most liberal
6864 wrt cross-module name binding. */
6866 bool
6867 default_binds_local_p (const_tree exp)
6869 return default_binds_local_p_1 (exp, flag_shlib);
6872 bool
6873 default_binds_local_p_1 (const_tree exp, int shlib)
6875 bool local_p;
6876 bool resolved_locally = false;
6877 bool resolved_to_local_def = false;
6879 /* With resolution file in hands, take look into resolutions.
6880 We can't just return true for resolved_locally symbols,
6881 because dynamic linking might overwrite symbols
6882 in shared libraries. */
6883 if (TREE_CODE (exp) == VAR_DECL && TREE_PUBLIC (exp)
6884 && (TREE_STATIC (exp) || DECL_EXTERNAL (exp)))
6886 struct varpool_node *vnode = varpool_get_node (exp);
6887 if (vnode && resolution_local_p (vnode->symbol.resolution))
6888 resolved_locally = true;
6889 if (vnode
6890 && resolution_to_local_definition_p (vnode->symbol.resolution))
6891 resolved_to_local_def = true;
6893 else if (TREE_CODE (exp) == FUNCTION_DECL && TREE_PUBLIC (exp))
6895 struct cgraph_node *node = cgraph_get_node (exp);
6896 if (node
6897 && resolution_local_p (node->symbol.resolution))
6898 resolved_locally = true;
6899 if (node
6900 && resolution_to_local_definition_p (node->symbol.resolution))
6901 resolved_to_local_def = true;
6904 /* A non-decl is an entry in the constant pool. */
6905 if (!DECL_P (exp))
6906 local_p = true;
6907 /* Weakrefs may not bind locally, even though the weakref itself is always
6908 static and therefore local. Similarly, the resolver for ifunc functions
6909 might resolve to a non-local function.
6910 FIXME: We can resolve the weakref case more curefuly by looking at the
6911 weakref alias. */
6912 else if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp))
6913 || (TREE_CODE (exp) == FUNCTION_DECL
6914 && lookup_attribute ("ifunc", DECL_ATTRIBUTES (exp))))
6915 local_p = false;
6916 /* Static variables are always local. */
6917 else if (! TREE_PUBLIC (exp))
6918 local_p = true;
6919 /* A variable is local if the user has said explicitly that it will
6920 be. */
6921 else if ((DECL_VISIBILITY_SPECIFIED (exp)
6922 || resolved_to_local_def)
6923 && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6924 local_p = true;
6925 /* Variables defined outside this object might not be local. */
6926 else if (DECL_EXTERNAL (exp) && !resolved_locally)
6927 local_p = false;
6928 /* If defined in this object and visibility is not default, must be
6929 local. */
6930 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6931 local_p = true;
6932 /* Default visibility weak data can be overridden by a strong symbol
6933 in another module and so are not local. */
6934 else if (DECL_WEAK (exp)
6935 && !resolved_locally)
6936 local_p = false;
6937 /* If PIC, then assume that any global name can be overridden by
6938 symbols resolved from other modules. */
6939 else if (shlib)
6940 local_p = false;
6941 /* Uninitialized COMMON variable may be unified with symbols
6942 resolved from other modules. */
6943 else if (DECL_COMMON (exp)
6944 && !resolved_locally
6945 && (DECL_INITIAL (exp) == NULL
6946 || DECL_INITIAL (exp) == error_mark_node))
6947 local_p = false;
6948 /* Otherwise we're left with initialized (or non-common) global data
6949 which is of necessity defined locally. */
6950 else
6951 local_p = true;
6953 return local_p;
6956 /* Return true when references to DECL must bind to current definition in
6957 final executable.
6959 The condition is usually equivalent to whether the function binds to the
6960 current module (shared library or executable), that is to binds_local_p.
6961 We use this fact to avoid need for another target hook and implement
6962 the logic using binds_local_p and just special cases where
6963 decl_binds_to_current_def_p is stronger than binds_local_p. In particular
6964 the weak definitions (that can be overwritten at linktime by other
6965 definition from different object file) and when resolution info is available
6966 we simply use the knowledge passed to us by linker plugin. */
6967 bool
6968 decl_binds_to_current_def_p (tree decl)
6970 gcc_assert (DECL_P (decl));
6971 if (!TREE_PUBLIC (decl))
6972 return true;
6973 if (!targetm.binds_local_p (decl))
6974 return false;
6975 /* When resolution is available, just use it. */
6976 if (TREE_CODE (decl) == VAR_DECL
6977 && (TREE_STATIC (decl) || DECL_EXTERNAL (decl)))
6979 struct varpool_node *vnode = varpool_get_node (decl);
6980 if (vnode
6981 && vnode->symbol.resolution != LDPR_UNKNOWN)
6982 return resolution_to_local_definition_p (vnode->symbol.resolution);
6984 else if (TREE_CODE (decl) == FUNCTION_DECL)
6986 struct cgraph_node *node = cgraph_get_node (decl);
6987 if (node
6988 && node->symbol.resolution != LDPR_UNKNOWN)
6989 return resolution_to_local_definition_p (node->symbol.resolution);
6991 /* Otherwise we have to assume the worst for DECL_WEAK (hidden weaks
6992 binds locally but still can be overwritten).
6993 This rely on fact that binds_local_p behave as decl_replaceable_p
6994 for all other declaration types. */
6995 return !DECL_WEAK (decl);
6998 /* A replaceable function or variable is one which may be replaced
6999 at link-time with an entirely different definition, provided that the
7000 replacement has the same type. For example, functions declared
7001 with __attribute__((weak)) on most systems are replaceable.
7003 COMDAT functions are not replaceable, since all definitions of the
7004 function must be equivalent. It is important that COMDAT functions
7005 not be treated as replaceable so that use of C++ template
7006 instantiations is not penalized. */
7008 bool
7009 decl_replaceable_p (tree decl)
7011 gcc_assert (DECL_P (decl));
7012 if (!TREE_PUBLIC (decl) || DECL_COMDAT (decl))
7013 return false;
7014 return !decl_binds_to_current_def_p (decl);
7017 /* Default function to output code that will globalize a label. A
7018 target must define GLOBAL_ASM_OP or provide its own function to
7019 globalize a label. */
7020 #ifdef GLOBAL_ASM_OP
7021 void
7022 default_globalize_label (FILE * stream, const char *name)
7024 fputs (GLOBAL_ASM_OP, stream);
7025 assemble_name (stream, name);
7026 putc ('\n', stream);
7028 #endif /* GLOBAL_ASM_OP */
7030 /* Default function to output code that will globalize a declaration. */
7031 void
7032 default_globalize_decl_name (FILE * stream, tree decl)
7034 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
7035 targetm.asm_out.globalize_label (stream, name);
7038 /* Default function to output a label for unwind information. The
7039 default is to do nothing. A target that needs nonlocal labels for
7040 unwind information must provide its own function to do this. */
7041 void
7042 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
7043 tree decl ATTRIBUTE_UNUSED,
7044 int for_eh ATTRIBUTE_UNUSED,
7045 int empty ATTRIBUTE_UNUSED)
7049 /* Default function to output a label to divide up the exception table.
7050 The default is to do nothing. A target that needs/wants to divide
7051 up the table must provide it's own function to do this. */
7052 void
7053 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
7057 /* This is how to output an internal numbered label where PREFIX is
7058 the class of label and LABELNO is the number within the class. */
7060 void
7061 default_generate_internal_label (char *buf, const char *prefix,
7062 unsigned long labelno)
7064 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
7067 /* This is how to output an internal numbered label where PREFIX is
7068 the class of label and LABELNO is the number within the class. */
7070 void
7071 default_internal_label (FILE *stream, const char *prefix,
7072 unsigned long labelno)
7074 char *const buf = (char *) alloca (40 + strlen (prefix));
7075 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
7076 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
7080 /* The default implementation of ASM_DECLARE_CONSTANT_NAME. */
7082 void
7083 default_asm_declare_constant_name (FILE *file, const char *name,
7084 const_tree exp ATTRIBUTE_UNUSED,
7085 HOST_WIDE_INT size ATTRIBUTE_UNUSED)
7087 assemble_label (file, name);
7090 /* This is the default behavior at the beginning of a file. It's
7091 controlled by two other target-hook toggles. */
7092 void
7093 default_file_start (void)
7095 if (targetm.asm_file_start_app_off
7096 && !(flag_verbose_asm || flag_debug_asm || flag_dump_rtl_in_asm))
7097 fputs (ASM_APP_OFF, asm_out_file);
7099 if (targetm.asm_file_start_file_directive)
7100 output_file_directive (asm_out_file, main_input_filename);
7103 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
7104 which emits a special section directive used to indicate whether or
7105 not this object file needs an executable stack. This is primarily
7106 a GNU extension to ELF but could be used on other targets. */
7108 int trampolines_created;
7110 void
7111 file_end_indicate_exec_stack (void)
7113 unsigned int flags = SECTION_DEBUG;
7114 if (trampolines_created)
7115 flags |= SECTION_CODE;
7117 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
7120 /* Emit a special section directive to indicate that this object file
7121 was compiled with -fsplit-stack. This is used to let the linker
7122 detect calls between split-stack code and non-split-stack code, so
7123 that it can modify the split-stack code to allocate a sufficiently
7124 large stack. We emit another special section if there are any
7125 functions in this file which have the no_split_stack attribute, to
7126 prevent the linker from warning about being unable to convert the
7127 functions if they call non-split-stack code. */
7129 void
7130 file_end_indicate_split_stack (void)
7132 if (flag_split_stack)
7134 switch_to_section (get_section (".note.GNU-split-stack", SECTION_DEBUG,
7135 NULL));
7136 if (saw_no_split_stack)
7137 switch_to_section (get_section (".note.GNU-no-split-stack",
7138 SECTION_DEBUG, NULL));
7142 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
7143 a get_unnamed_section callback. */
7145 void
7146 output_section_asm_op (const void *directive)
7148 fprintf (asm_out_file, "%s\n", (const char *) directive);
7151 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
7152 the current section is NEW_SECTION. */
7154 void
7155 switch_to_section (section *new_section)
7157 if (in_section == new_section)
7158 return;
7160 if (new_section->common.flags & SECTION_FORGET)
7161 in_section = NULL;
7162 else
7163 in_section = new_section;
7165 switch (SECTION_STYLE (new_section))
7167 case SECTION_NAMED:
7168 targetm.asm_out.named_section (new_section->named.name,
7169 new_section->named.common.flags,
7170 new_section->named.decl);
7171 break;
7173 case SECTION_UNNAMED:
7174 new_section->unnamed.callback (new_section->unnamed.data);
7175 break;
7177 case SECTION_NOSWITCH:
7178 gcc_unreachable ();
7179 break;
7182 new_section->common.flags |= SECTION_DECLARED;
7185 /* If block symbol SYMBOL has not yet been assigned an offset, place
7186 it at the end of its block. */
7188 void
7189 place_block_symbol (rtx symbol)
7191 unsigned HOST_WIDE_INT size, mask, offset;
7192 struct constant_descriptor_rtx *desc;
7193 unsigned int alignment;
7194 struct object_block *block;
7195 tree decl;
7197 gcc_assert (SYMBOL_REF_BLOCK (symbol));
7198 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
7199 return;
7201 /* Work out the symbol's size and alignment. */
7202 if (CONSTANT_POOL_ADDRESS_P (symbol))
7204 desc = SYMBOL_REF_CONSTANT (symbol);
7205 alignment = desc->align;
7206 size = GET_MODE_SIZE (desc->mode);
7208 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7210 decl = SYMBOL_REF_DECL (symbol);
7211 alignment = DECL_ALIGN (decl);
7212 size = get_constant_size (DECL_INITIAL (decl));
7214 else
7216 decl = SYMBOL_REF_DECL (symbol);
7217 alignment = DECL_ALIGN (decl);
7218 size = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
7221 /* Calculate the object's offset from the start of the block. */
7222 block = SYMBOL_REF_BLOCK (symbol);
7223 mask = alignment / BITS_PER_UNIT - 1;
7224 offset = (block->size + mask) & ~mask;
7225 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
7227 /* Record the block's new alignment and size. */
7228 block->alignment = MAX (block->alignment, alignment);
7229 block->size = offset + size;
7231 VEC_safe_push (rtx, gc, block->objects, symbol);
7234 /* Return the anchor that should be used to address byte offset OFFSET
7235 from the first object in BLOCK. MODEL is the TLS model used
7236 to access it. */
7239 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
7240 enum tls_model model)
7242 char label[100];
7243 unsigned int begin, middle, end;
7244 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
7245 rtx anchor;
7247 /* Work out the anchor's offset. Use an offset of 0 for the first
7248 anchor so that we don't pessimize the case where we take the address
7249 of a variable at the beginning of the block. This is particularly
7250 useful when a block has only one variable assigned to it.
7252 We try to place anchors RANGE bytes apart, so there can then be
7253 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
7254 a ptr_mode offset. With some target settings, the lowest such
7255 anchor might be out of range for the lowest ptr_mode offset;
7256 likewise the highest anchor for the highest offset. Use anchors
7257 at the extreme ends of the ptr_mode range in such cases.
7259 All arithmetic uses unsigned integers in order to avoid
7260 signed overflow. */
7261 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
7262 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
7263 range = max_offset - min_offset + 1;
7264 if (range == 0)
7265 offset = 0;
7266 else
7268 bias = 1 << (GET_MODE_BITSIZE (ptr_mode) - 1);
7269 if (offset < 0)
7271 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
7272 delta -= delta % range;
7273 if (delta > bias)
7274 delta = bias;
7275 offset = (HOST_WIDE_INT) (-delta);
7277 else
7279 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
7280 delta -= delta % range;
7281 if (delta > bias - 1)
7282 delta = bias - 1;
7283 offset = (HOST_WIDE_INT) delta;
7287 /* Do a binary search to see if there's already an anchor we can use.
7288 Set BEGIN to the new anchor's index if not. */
7289 begin = 0;
7290 end = VEC_length (rtx, block->anchors);
7291 while (begin != end)
7293 middle = (end + begin) / 2;
7294 anchor = VEC_index (rtx, block->anchors, middle);
7295 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
7296 end = middle;
7297 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
7298 begin = middle + 1;
7299 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
7300 end = middle;
7301 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
7302 begin = middle + 1;
7303 else
7304 return anchor;
7307 /* Create a new anchor with a unique label. */
7308 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
7309 anchor = create_block_symbol (ggc_strdup (label), block, offset);
7310 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
7311 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
7313 /* Insert it at index BEGIN. */
7314 VEC_safe_insert (rtx, gc, block->anchors, begin, anchor);
7315 return anchor;
7318 /* Output the objects in BLOCK. */
7320 static void
7321 output_object_block (struct object_block *block)
7323 struct constant_descriptor_rtx *desc;
7324 unsigned int i;
7325 HOST_WIDE_INT offset;
7326 tree decl;
7327 rtx symbol;
7329 if (block->objects == NULL)
7330 return;
7332 /* Switch to the section and make sure that the first byte is
7333 suitably aligned. */
7334 switch_to_section (block->sect);
7335 assemble_align (block->alignment);
7337 /* Define the values of all anchors relative to the current section
7338 position. */
7339 FOR_EACH_VEC_ELT (rtx, block->anchors, i, symbol)
7340 targetm.asm_out.output_anchor (symbol);
7342 /* Output the objects themselves. */
7343 offset = 0;
7344 FOR_EACH_VEC_ELT (rtx, block->objects, i, symbol)
7346 /* Move to the object's offset, padding with zeros if necessary. */
7347 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
7348 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
7349 if (CONSTANT_POOL_ADDRESS_P (symbol))
7351 desc = SYMBOL_REF_CONSTANT (symbol);
7352 output_constant_pool_1 (desc, 1);
7353 offset += GET_MODE_SIZE (desc->mode);
7355 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
7357 decl = SYMBOL_REF_DECL (symbol);
7358 assemble_constant_contents (DECL_INITIAL (decl), XSTR (symbol, 0),
7359 DECL_ALIGN (decl));
7360 offset += get_constant_size (DECL_INITIAL (decl));
7362 else
7364 decl = SYMBOL_REF_DECL (symbol);
7365 assemble_variable_contents (decl, XSTR (symbol, 0), false);
7366 offset += tree_low_cst (DECL_SIZE_UNIT (decl), 1);
7371 /* A htab_traverse callback used to call output_object_block for
7372 each member of object_block_htab. */
7374 static int
7375 output_object_block_htab (void **slot, void *data ATTRIBUTE_UNUSED)
7377 output_object_block ((struct object_block *) (*slot));
7378 return 1;
7381 /* Output the definitions of all object_blocks. */
7383 void
7384 output_object_blocks (void)
7386 htab_traverse (object_block_htab, output_object_block_htab, NULL);
7389 /* This function provides a possible implementation of the
7390 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
7391 by -frecord-gcc-switches it creates a new mergeable, string section in the
7392 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
7393 contains the switches in ASCII format.
7395 FIXME: This code does not correctly handle double quote characters
7396 that appear inside strings, (it strips them rather than preserving them).
7397 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
7398 characters - instead it treats them as sub-string separators. Since
7399 we want to emit NUL strings terminators into the object file we have to use
7400 ASM_OUTPUT_SKIP. */
7403 elf_record_gcc_switches (print_switch_type type, const char * name)
7405 switch (type)
7407 case SWITCH_TYPE_PASSED:
7408 ASM_OUTPUT_ASCII (asm_out_file, name, strlen (name));
7409 ASM_OUTPUT_SKIP (asm_out_file, (unsigned HOST_WIDE_INT) 1);
7410 break;
7412 case SWITCH_TYPE_DESCRIPTIVE:
7413 if (name == NULL)
7415 /* Distinguish between invocations where name is NULL. */
7416 static bool started = false;
7418 if (!started)
7420 section * sec;
7422 sec = get_section (targetm.asm_out.record_gcc_switches_section,
7423 SECTION_DEBUG
7424 | SECTION_MERGE
7425 | SECTION_STRINGS
7426 | (SECTION_ENTSIZE & 1),
7427 NULL);
7428 switch_to_section (sec);
7429 started = true;
7433 default:
7434 break;
7437 /* The return value is currently ignored by the caller, but must be 0.
7438 For -fverbose-asm the return value would be the number of characters
7439 emitted into the assembler file. */
7440 return 0;
7443 /* Emit text to declare externally defined symbols. It is needed to
7444 properly support non-default visibility. */
7445 void
7446 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
7447 tree decl,
7448 const char *name ATTRIBUTE_UNUSED)
7450 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
7451 set in order to avoid putting out names that are never really
7452 used. */
7453 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
7454 && targetm.binds_local_p (decl))
7455 maybe_assemble_visibility (decl);
7458 /* The default hook for TARGET_ASM_OUTPUT_SOURCE_FILENAME. */
7460 void
7461 default_asm_output_source_filename (FILE *file, const char *name)
7463 #ifdef ASM_OUTPUT_SOURCE_FILENAME
7464 ASM_OUTPUT_SOURCE_FILENAME (file, name);
7465 #else
7466 fprintf (file, "\t.file\t");
7467 output_quoted_string (file, name);
7468 putc ('\n', file);
7469 #endif
7472 /* Output a file name in the form wanted by System V. */
7474 void
7475 output_file_directive (FILE *asm_file, const char *input_name)
7477 int len;
7478 const char *na;
7480 if (input_name == NULL)
7481 input_name = "<stdin>";
7482 else
7483 input_name = remap_debug_filename (input_name);
7485 len = strlen (input_name);
7486 na = input_name + len;
7488 /* NA gets INPUT_NAME sans directory names. */
7489 while (na > input_name)
7491 if (IS_DIR_SEPARATOR (na[-1]))
7492 break;
7493 na--;
7496 targetm.asm_out.output_source_filename (asm_file, na);
7499 /* Create a DEBUG_EXPR_DECL / DEBUG_EXPR pair from RTL expression
7500 EXP. */
7502 make_debug_expr_from_rtl (const_rtx exp)
7504 tree ddecl = make_node (DEBUG_EXPR_DECL), type;
7505 enum machine_mode mode = GET_MODE (exp);
7506 rtx dval;
7508 DECL_ARTIFICIAL (ddecl) = 1;
7509 if (REG_P (exp) && REG_EXPR (exp))
7510 type = TREE_TYPE (REG_EXPR (exp));
7511 else if (MEM_P (exp) && MEM_EXPR (exp))
7512 type = TREE_TYPE (MEM_EXPR (exp));
7513 else
7514 type = NULL_TREE;
7515 if (type && TYPE_MODE (type) == mode)
7516 TREE_TYPE (ddecl) = type;
7517 else
7518 TREE_TYPE (ddecl) = lang_hooks.types.type_for_mode (mode, 1);
7519 DECL_MODE (ddecl) = mode;
7520 dval = gen_rtx_DEBUG_EXPR (mode);
7521 DEBUG_EXPR_TREE_DECL (dval) = ddecl;
7522 SET_DECL_RTL (ddecl, dval);
7523 return dval;
7526 #ifdef ELF_ASCII_ESCAPES
7527 /* Default ASM_OUTPUT_LIMITED_STRING for ELF targets. */
7529 void
7530 default_elf_asm_output_limited_string (FILE *f, const char *s)
7532 int escape;
7533 unsigned char c;
7535 fputs (STRING_ASM_OP, f);
7536 putc ('"', f);
7537 while (*s != '\0')
7539 c = *s;
7540 escape = ELF_ASCII_ESCAPES[c];
7541 switch (escape)
7543 case 0:
7544 putc (c, f);
7545 break;
7546 case 1:
7547 /* TODO: Print in hex with fast function, important for -flto. */
7548 fprintf (f, "\\%03o", c);
7549 break;
7550 default:
7551 putc ('\\', f);
7552 putc (escape, f);
7553 break;
7555 s++;
7557 putc ('\"', f);
7558 putc ('\n', f);
7561 /* Default ASM_OUTPUT_ASCII for ELF targets. */
7563 void
7564 default_elf_asm_output_ascii (FILE *f, const char *s, unsigned int len)
7566 const char *limit = s + len;
7567 const char *last_null = NULL;
7568 unsigned bytes_in_chunk = 0;
7569 unsigned char c;
7570 int escape;
7572 for (; s < limit; s++)
7574 const char *p;
7576 if (bytes_in_chunk >= 60)
7578 putc ('\"', f);
7579 putc ('\n', f);
7580 bytes_in_chunk = 0;
7583 if (s > last_null)
7585 for (p = s; p < limit && *p != '\0'; p++)
7586 continue;
7587 last_null = p;
7589 else
7590 p = last_null;
7592 if (p < limit && (p - s) <= (long) ELF_STRING_LIMIT)
7594 if (bytes_in_chunk > 0)
7596 putc ('\"', f);
7597 putc ('\n', f);
7598 bytes_in_chunk = 0;
7601 default_elf_asm_output_limited_string (f, s);
7602 s = p;
7604 else
7606 if (bytes_in_chunk == 0)
7607 fputs (ASCII_DATA_ASM_OP "\"", f);
7609 c = *s;
7610 escape = ELF_ASCII_ESCAPES[c];
7611 switch (escape)
7613 case 0:
7614 putc (c, f);
7615 bytes_in_chunk++;
7616 break;
7617 case 1:
7618 /* TODO: Print in hex with fast function, important for -flto. */
7619 fprintf (f, "\\%03o", c);
7620 bytes_in_chunk += 4;
7621 break;
7622 default:
7623 putc ('\\', f);
7624 putc (escape, f);
7625 bytes_in_chunk += 2;
7626 break;
7632 if (bytes_in_chunk > 0)
7634 putc ('\"', f);
7635 putc ('\n', f);
7638 #endif
7640 static GTY(()) section *elf_init_array_section;
7641 static GTY(()) section *elf_fini_array_section;
7643 static section *
7644 get_elf_initfini_array_priority_section (int priority,
7645 bool constructor_p)
7647 section *sec;
7648 if (priority != DEFAULT_INIT_PRIORITY)
7650 char buf[18];
7651 sprintf (buf, "%s.%.5u",
7652 constructor_p ? ".init_array" : ".fini_array",
7653 priority);
7654 sec = get_section (buf, SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7656 else
7658 if (constructor_p)
7660 if (elf_init_array_section == NULL)
7661 elf_init_array_section
7662 = get_section (".init_array",
7663 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7664 sec = elf_init_array_section;
7666 else
7668 if (elf_fini_array_section == NULL)
7669 elf_fini_array_section
7670 = get_section (".fini_array",
7671 SECTION_WRITE | SECTION_NOTYPE, NULL_TREE);
7672 sec = elf_fini_array_section;
7675 return sec;
7678 /* Use .init_array section for constructors. */
7680 void
7681 default_elf_init_array_asm_out_constructor (rtx symbol, int priority)
7683 section *sec = get_elf_initfini_array_priority_section (priority,
7684 true);
7685 assemble_addr_to_section (symbol, sec);
7688 /* Use .fini_array section for destructors. */
7690 void
7691 default_elf_fini_array_asm_out_destructor (rtx symbol, int priority)
7693 section *sec = get_elf_initfini_array_priority_section (priority,
7694 false);
7695 assemble_addr_to_section (symbol, sec);
7698 #include "gt-varasm.h"