2008-05-07 Kai Tietz <kai,tietz@onevision.com>
[official-gcc.git] / gcc / varasm.c
blob0d22fc33c0c7a70f6b28f64cead6c6ea0e124848
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
4 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 "real.h"
42 #include "output.h"
43 #include "toplev.h"
44 #include "hashtab.h"
45 #include "c-pragma.h"
46 #include "ggc.h"
47 #include "langhooks.h"
48 #include "tm_p.h"
49 #include "debug.h"
50 #include "target.h"
51 #include "targhooks.h"
52 #include "tree-mudflap.h"
53 #include "cgraph.h"
54 #include "cfglayout.h"
55 #include "basic-block.h"
56 #include "tree-iterator.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 static const char *strip_reg_name (const char *);
104 static int contains_pointers_p (tree);
105 #ifdef ASM_OUTPUT_EXTERNAL
106 static bool incorporeal_function_p (tree);
107 #endif
108 static void decode_addr_const (tree, struct addr_const *);
109 static hashval_t const_desc_hash (const void *);
110 static int const_desc_eq (const void *, const void *);
111 static hashval_t const_hash_1 (const tree);
112 static int compare_constant (const tree, const tree);
113 static tree copy_constant (tree);
114 static void output_constant_def_contents (rtx);
115 static void output_addressed_constants (tree);
116 static unsigned HOST_WIDE_INT array_size_for_constructor (tree);
117 static unsigned min_align (unsigned, unsigned);
118 static void output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int);
119 static void globalize_decl (tree);
120 #ifdef BSS_SECTION_ASM_OP
121 #ifdef ASM_OUTPUT_BSS
122 static void asm_output_bss (FILE *, tree, const char *,
123 unsigned HOST_WIDE_INT, unsigned HOST_WIDE_INT);
124 #endif
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 #ifndef IN_NAMED_SECTION
176 #define IN_NAMED_SECTION(DECL) \
177 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \
178 && DECL_SECTION_NAME (DECL) != NULL_TREE)
179 #endif
181 /* Hash table of named sections. */
182 static GTY((param_is (section))) htab_t section_htab;
184 /* A table of object_blocks, indexed by section. */
185 static GTY((param_is (struct object_block))) htab_t object_block_htab;
187 /* The next number to use for internal anchor labels. */
188 static GTY(()) int anchor_labelno;
190 /* A pool of constants that can be shared between functions. */
191 static GTY(()) struct rtx_constant_pool *shared_constant_pool;
193 /* TLS emulation. */
195 static GTY ((if_marked ("tree_map_marked_p"), param_is (struct tree_map)))
196 htab_t emutls_htab;
197 static GTY (()) tree emutls_object_type;
198 /* Emulated TLS objects have the TLS model TLS_MODEL_EMULATED. This
199 macro can be used on them to distinguish the control variable from
200 the initialization template. */
201 #define DECL_EMUTLS_VAR_P(D) (TREE_TYPE (D) == emutls_object_type)
203 #if !defined (NO_DOT_IN_LABEL)
204 # define EMUTLS_SEPARATOR "."
205 #elif !defined (NO_DOLLAR_IN_LABEL)
206 # define EMUTLS_SEPARATOR "$"
207 #else
208 # define EMUTLS_SEPARATOR "_"
209 #endif
211 /* Create an IDENTIFIER_NODE by prefixing PREFIX to the
212 IDENTIFIER_NODE NAME's name. */
214 static tree
215 prefix_name (const char *prefix, tree name)
217 unsigned plen = strlen (prefix);
218 unsigned nlen = strlen (IDENTIFIER_POINTER (name));
219 char *toname = alloca (plen + nlen + 1);
221 memcpy (toname, prefix, plen);
222 memcpy (toname + plen, IDENTIFIER_POINTER (name), nlen + 1);
224 return get_identifier (toname);
227 /* Create an identifier for the struct __emutls_object, given an identifier
228 of the DECL_ASSEMBLY_NAME of the original object. */
230 static tree
231 get_emutls_object_name (tree name)
233 const char *prefix = (targetm.emutls.var_prefix
234 ? targetm.emutls.var_prefix
235 : "__emutls_v" EMUTLS_SEPARATOR);
236 return prefix_name (prefix, name);
239 tree
240 default_emutls_var_fields (tree type, tree *name ATTRIBUTE_UNUSED)
242 tree word_type_node, field, next_field;
244 field = build_decl (FIELD_DECL, get_identifier ("__templ"), ptr_type_node);
245 DECL_CONTEXT (field) = type;
246 next_field = field;
248 field = build_decl (FIELD_DECL, get_identifier ("__offset"),
249 ptr_type_node);
250 DECL_CONTEXT (field) = type;
251 TREE_CHAIN (field) = next_field;
252 next_field = field;
254 word_type_node = lang_hooks.types.type_for_mode (word_mode, 1);
255 field = build_decl (FIELD_DECL, get_identifier ("__align"),
256 word_type_node);
257 DECL_CONTEXT (field) = type;
258 TREE_CHAIN (field) = next_field;
259 next_field = field;
261 field = build_decl (FIELD_DECL, get_identifier ("__size"), word_type_node);
262 DECL_CONTEXT (field) = type;
263 TREE_CHAIN (field) = next_field;
265 return field;
268 /* Create the structure for struct __emutls_object. This should match the
269 structure at the top of emutls.c, modulo the union there. */
271 static tree
272 get_emutls_object_type (void)
274 tree type, type_name, field;
276 type = emutls_object_type;
277 if (type)
278 return type;
280 emutls_object_type = type = lang_hooks.types.make_type (RECORD_TYPE);
281 type_name = NULL;
282 field = targetm.emutls.var_fields (type, &type_name);
283 if (!type_name)
284 type_name = get_identifier ("__emutls_object");
285 type_name = build_decl (TYPE_DECL, type_name, type);
286 TYPE_NAME (type) = type_name;
287 TYPE_FIELDS (type) = field;
288 layout_type (type);
290 return type;
293 /* Create a read-only variable like DECL, with the same DECL_INITIAL.
294 This will be used for initializing the emulated tls data area. */
296 static tree
297 get_emutls_init_templ_addr (tree decl)
299 tree name, to;
301 if (targetm.emutls.register_common && !DECL_INITIAL (decl)
302 && !DECL_SECTION_NAME (decl))
303 return null_pointer_node;
305 name = DECL_ASSEMBLER_NAME (decl);
306 if (!targetm.emutls.tmpl_prefix || targetm.emutls.tmpl_prefix[0])
308 const char *prefix = (targetm.emutls.tmpl_prefix
309 ? targetm.emutls.tmpl_prefix
310 : "__emutls_t" EMUTLS_SEPARATOR);
311 name = prefix_name (prefix, name);
314 to = build_decl (VAR_DECL, name, TREE_TYPE (decl));
315 SET_DECL_ASSEMBLER_NAME (to, DECL_NAME (to));
316 DECL_TLS_MODEL (to) = TLS_MODEL_EMULATED;
317 DECL_ARTIFICIAL (to) = 1;
318 TREE_USED (to) = TREE_USED (decl);
319 TREE_READONLY (to) = 1;
320 DECL_IGNORED_P (to) = 1;
321 DECL_CONTEXT (to) = DECL_CONTEXT (decl);
322 DECL_SECTION_NAME (to) = DECL_SECTION_NAME (decl);
324 DECL_WEAK (to) = DECL_WEAK (decl);
325 if (DECL_ONE_ONLY (decl))
327 make_decl_one_only (to);
328 TREE_STATIC (to) = TREE_STATIC (decl);
329 TREE_PUBLIC (to) = TREE_PUBLIC (decl);
330 DECL_VISIBILITY (to) = DECL_VISIBILITY (decl);
332 else
333 TREE_STATIC (to) = 1;
335 DECL_INITIAL (to) = DECL_INITIAL (decl);
336 DECL_INITIAL (decl) = NULL;
338 varpool_finalize_decl (to);
339 return build_fold_addr_expr (to);
342 /* When emulating tls, we use a control structure for use by the runtime.
343 Create and return this structure. */
345 tree
346 emutls_decl (tree decl)
348 tree name, to;
349 struct tree_map *h, in;
350 void **loc;
352 if (targetm.have_tls || decl == NULL || decl == error_mark_node
353 || TREE_CODE (decl) != VAR_DECL || ! DECL_THREAD_LOCAL_P (decl))
354 return decl;
356 /* Look up the object in the hash; return the control structure if
357 it has already been created. */
358 if (! emutls_htab)
359 emutls_htab = htab_create_ggc (512, tree_map_hash, tree_map_eq, 0);
361 name = DECL_ASSEMBLER_NAME (decl);
363 /* Note that we use the hash of the decl's name, rather than a hash
364 of the decl's pointer. In emutls_finish we iterate through the
365 hash table, and we want this traversal to be predictable. */
366 in.hash = htab_hash_string (IDENTIFIER_POINTER (name));
367 in.base.from = decl;
368 loc = htab_find_slot_with_hash (emutls_htab, &in, in.hash, INSERT);
369 h = *loc;
370 if (h != NULL)
371 to = h->to;
372 else
374 to = build_decl (VAR_DECL, get_emutls_object_name (name),
375 get_emutls_object_type ());
377 h = ggc_alloc (sizeof (struct tree_map));
378 h->hash = in.hash;
379 h->base.from = decl;
380 h->to = to;
381 *(struct tree_map **) loc = h;
383 DECL_TLS_MODEL (to) = TLS_MODEL_EMULATED;
384 DECL_ARTIFICIAL (to) = 1;
385 DECL_IGNORED_P (to) = 1;
386 TREE_READONLY (to) = 0;
387 SET_DECL_ASSEMBLER_NAME (to, DECL_NAME (to));
388 if (DECL_ONE_ONLY (decl))
389 make_decl_one_only (to);
390 DECL_CONTEXT (to) = DECL_CONTEXT (decl);
391 if (targetm.emutls.var_align_fixed)
392 /* If we're not allowed to change the proxy object's
393 alignment, pretend it's been set by the user. */
394 DECL_USER_ALIGN (to) = 1;
397 /* Note that these fields may need to be updated from time to time from
398 the original decl. Consider:
399 extern __thread int i;
400 int foo() { return i; }
401 __thread int i = 1;
402 in which I goes from external to locally defined and initialized. */
404 TREE_STATIC (to) = TREE_STATIC (decl);
405 TREE_USED (to) = TREE_USED (decl);
406 TREE_PUBLIC (to) = TREE_PUBLIC (decl);
407 DECL_EXTERNAL (to) = DECL_EXTERNAL (decl);
408 DECL_COMMON (to) = DECL_COMMON (decl);
409 DECL_WEAK (to) = DECL_WEAK (decl);
410 DECL_VISIBILITY (to) = DECL_VISIBILITY (decl);
412 return to;
415 static int
416 emutls_common_1 (void **loc, void *xstmts)
418 struct tree_map *h = *(struct tree_map **) loc;
419 tree args, x, *pstmts = (tree *) xstmts;
420 tree word_type_node;
422 if (! DECL_COMMON (h->base.from)
423 || (DECL_INITIAL (h->base.from)
424 && DECL_INITIAL (h->base.from) != error_mark_node))
425 return 1;
427 word_type_node = lang_hooks.types.type_for_mode (word_mode, 1);
429 /* The idea was to call get_emutls_init_templ_addr here, but if we
430 do this and there is an initializer, -fanchor_section loses,
431 because it would be too late to ensure the template is
432 output. */
433 x = null_pointer_node;
434 args = tree_cons (NULL, x, NULL);
435 x = build_int_cst (word_type_node, DECL_ALIGN_UNIT (h->base.from));
436 args = tree_cons (NULL, x, args);
437 x = fold_convert (word_type_node, DECL_SIZE_UNIT (h->base.from));
438 args = tree_cons (NULL, x, args);
439 x = build_fold_addr_expr (h->to);
440 args = tree_cons (NULL, x, args);
442 x = built_in_decls[BUILT_IN_EMUTLS_REGISTER_COMMON];
443 x = build_function_call_expr (x, args);
445 append_to_statement_list (x, pstmts);
446 return 1;
449 void
450 emutls_finish (void)
452 if (!targetm.emutls.register_common)
454 tree body = NULL_TREE;
456 if (emutls_htab == NULL)
457 return;
459 htab_traverse_noresize (emutls_htab, emutls_common_1, &body);
460 if (body == NULL_TREE)
461 return;
463 cgraph_build_static_cdtor ('I', body, DEFAULT_INIT_PRIORITY);
467 /* Helper routines for maintaining section_htab. */
469 static int
470 section_entry_eq (const void *p1, const void *p2)
472 const section *old = p1;
473 const char *new = p2;
475 return strcmp (old->named.name, new) == 0;
478 static hashval_t
479 section_entry_hash (const void *p)
481 const section *old = p;
482 return htab_hash_string (old->named.name);
485 /* Return a hash value for section SECT. */
487 static hashval_t
488 hash_section (section *sect)
490 if (sect->common.flags & SECTION_NAMED)
491 return htab_hash_string (sect->named.name);
492 return sect->common.flags;
495 /* Helper routines for maintaining object_block_htab. */
497 static int
498 object_block_entry_eq (const void *p1, const void *p2)
500 const struct object_block *old = p1;
501 const section *new = p2;
503 return old->sect == new;
506 static hashval_t
507 object_block_entry_hash (const void *p)
509 const struct object_block *old = p;
510 return hash_section (old->sect);
513 /* Return a new unnamed section with the given fields. */
515 section *
516 get_unnamed_section (unsigned int flags, void (*callback) (const void *),
517 const void *data)
519 section *sect;
521 sect = ggc_alloc (sizeof (struct unnamed_section));
522 sect->unnamed.common.flags = flags | SECTION_UNNAMED;
523 sect->unnamed.callback = callback;
524 sect->unnamed.data = data;
525 sect->unnamed.next = unnamed_sections;
527 unnamed_sections = sect;
528 return sect;
531 /* Return a SECTION_NOSWITCH section with the given fields. */
533 static section *
534 get_noswitch_section (unsigned int flags, noswitch_section_callback callback)
536 section *sect;
538 sect = ggc_alloc (sizeof (struct unnamed_section));
539 sect->noswitch.common.flags = flags | SECTION_NOSWITCH;
540 sect->noswitch.callback = callback;
542 return sect;
545 /* Return the named section structure associated with NAME. Create
546 a new section with the given fields if no such structure exists. */
548 section *
549 get_section (const char *name, unsigned int flags, tree decl)
551 section *sect, **slot;
553 slot = (section **)
554 htab_find_slot_with_hash (section_htab, name,
555 htab_hash_string (name), INSERT);
556 flags |= SECTION_NAMED;
557 if (*slot == NULL)
559 sect = ggc_alloc (sizeof (struct named_section));
560 sect->named.common.flags = flags;
561 sect->named.name = ggc_strdup (name);
562 sect->named.decl = decl;
563 *slot = sect;
565 else
567 sect = *slot;
568 if ((sect->common.flags & ~SECTION_DECLARED) != flags
569 && ((sect->common.flags | flags) & SECTION_OVERRIDE) == 0)
571 /* Sanity check user variables for flag changes. */
572 if (decl == 0)
573 decl = sect->named.decl;
574 gcc_assert (decl);
575 error ("%+D causes a section type conflict", decl);
578 return sect;
581 /* Return true if the current compilation mode benefits from having
582 objects grouped into blocks. */
584 static bool
585 use_object_blocks_p (void)
587 return flag_section_anchors;
590 /* Return the object_block structure for section SECT. Create a new
591 structure if we haven't created one already. Return null if SECT
592 itself is null. */
594 static struct object_block *
595 get_block_for_section (section *sect)
597 struct object_block *block;
598 void **slot;
600 if (sect == NULL)
601 return NULL;
603 slot = htab_find_slot_with_hash (object_block_htab, sect,
604 hash_section (sect), INSERT);
605 block = (struct object_block *) *slot;
606 if (block == NULL)
608 block = (struct object_block *)
609 ggc_alloc_cleared (sizeof (struct object_block));
610 block->sect = sect;
611 *slot = block;
613 return block;
616 /* Create a symbol with label LABEL and place it at byte offset
617 OFFSET in BLOCK. OFFSET can be negative if the symbol's offset
618 is not yet known. LABEL must be a garbage-collected string. */
620 static rtx
621 create_block_symbol (const char *label, struct object_block *block,
622 HOST_WIDE_INT offset)
624 rtx symbol;
625 unsigned int size;
627 /* Create the extended SYMBOL_REF. */
628 size = RTX_HDR_SIZE + sizeof (struct block_symbol);
629 symbol = ggc_alloc_zone (size, &rtl_zone);
631 /* Initialize the normal SYMBOL_REF fields. */
632 memset (symbol, 0, size);
633 PUT_CODE (symbol, SYMBOL_REF);
634 PUT_MODE (symbol, Pmode);
635 XSTR (symbol, 0) = label;
636 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_HAS_BLOCK_INFO;
638 /* Initialize the block_symbol stuff. */
639 SYMBOL_REF_BLOCK (symbol) = block;
640 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
642 return symbol;
645 static void
646 initialize_cold_section_name (void)
648 const char *stripped_name;
649 char *name, *buffer;
650 tree dsn;
652 gcc_assert (cfun && current_function_decl);
653 if (crtl->subsections.unlikely_text_section_name)
654 return;
656 dsn = DECL_SECTION_NAME (current_function_decl);
657 if (flag_function_sections && dsn)
659 name = alloca (TREE_STRING_LENGTH (dsn) + 1);
660 memcpy (name, TREE_STRING_POINTER (dsn), TREE_STRING_LENGTH (dsn) + 1);
662 stripped_name = targetm.strip_name_encoding (name);
664 buffer = ACONCAT ((stripped_name, "_unlikely", NULL));
665 crtl->subsections.unlikely_text_section_name = ggc_strdup (buffer);
667 else
668 crtl->subsections.unlikely_text_section_name = UNLIKELY_EXECUTED_TEXT_SECTION_NAME;
671 /* Tell assembler to switch to unlikely-to-be-executed text section. */
673 section *
674 unlikely_text_section (void)
676 if (cfun)
678 if (!crtl->subsections.unlikely_text_section_name)
679 initialize_cold_section_name ();
681 return get_named_section (NULL, crtl->subsections.unlikely_text_section_name, 0);
683 else
684 return get_named_section (NULL, UNLIKELY_EXECUTED_TEXT_SECTION_NAME, 0);
687 /* When called within a function context, return true if the function
688 has been assigned a cold text section and if SECT is that section.
689 When called outside a function context, return true if SECT is the
690 default cold section. */
692 bool
693 unlikely_text_section_p (section *sect)
695 const char *name;
697 if (cfun)
698 name = crtl->subsections.unlikely_text_section_name;
699 else
700 name = UNLIKELY_EXECUTED_TEXT_SECTION_NAME;
702 return (name
703 && sect
704 && SECTION_STYLE (sect) == SECTION_NAMED
705 && strcmp (name, sect->named.name) == 0);
708 /* Return a section with a particular name and with whatever SECTION_*
709 flags section_type_flags deems appropriate. The name of the section
710 is taken from NAME if nonnull, otherwise it is taken from DECL's
711 DECL_SECTION_NAME. DECL is the decl associated with the section
712 (see the section comment for details) and RELOC is as for
713 section_type_flags. */
715 section *
716 get_named_section (tree decl, const char *name, int reloc)
718 unsigned int flags;
720 gcc_assert (!decl || DECL_P (decl));
721 if (name == NULL)
722 name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
724 flags = targetm.section_type_flags (decl, name, reloc);
726 return get_section (name, flags, decl);
729 /* If required, set DECL_SECTION_NAME to a unique name. */
731 void
732 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
733 int flag_function_or_data_sections)
735 if (DECL_SECTION_NAME (decl) == NULL_TREE
736 && targetm.have_named_sections
737 && (flag_function_or_data_sections
738 || DECL_ONE_ONLY (decl)))
739 targetm.asm_out.unique_section (decl, reloc);
742 #ifdef BSS_SECTION_ASM_OP
744 #ifdef ASM_OUTPUT_BSS
746 /* Utility function for ASM_OUTPUT_BSS for targets to use if
747 they don't support alignments in .bss.
748 ??? It is believed that this function will work in most cases so such
749 support is localized here. */
751 static void
752 asm_output_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
753 const char *name,
754 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
755 unsigned HOST_WIDE_INT rounded)
757 gcc_assert (strcmp (XSTR (XEXP (DECL_RTL (decl), 0), 0), name) == 0);
758 targetm.asm_out.globalize_decl_name (file, decl);
759 switch_to_section (bss_section);
760 #ifdef ASM_DECLARE_OBJECT_NAME
761 last_assemble_variable_decl = decl;
762 ASM_DECLARE_OBJECT_NAME (file, name, decl);
763 #else
764 /* Standard thing is just output label for the object. */
765 ASM_OUTPUT_LABEL (file, name);
766 #endif /* ASM_DECLARE_OBJECT_NAME */
767 ASM_OUTPUT_SKIP (file, rounded ? rounded : 1);
770 #endif
772 #ifdef ASM_OUTPUT_ALIGNED_BSS
774 /* Utility function for targets to use in implementing
775 ASM_OUTPUT_ALIGNED_BSS.
776 ??? It is believed that this function will work in most cases so such
777 support is localized here. */
779 static void
780 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
781 const char *name, unsigned HOST_WIDE_INT size,
782 int align)
784 switch_to_section (bss_section);
785 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
786 #ifdef ASM_DECLARE_OBJECT_NAME
787 last_assemble_variable_decl = decl;
788 ASM_DECLARE_OBJECT_NAME (file, name, decl);
789 #else
790 /* Standard thing is just output label for the object. */
791 ASM_OUTPUT_LABEL (file, name);
792 #endif /* ASM_DECLARE_OBJECT_NAME */
793 ASM_OUTPUT_SKIP (file, size ? size : 1);
796 #endif
798 #endif /* BSS_SECTION_ASM_OP */
800 #ifndef USE_SELECT_SECTION_FOR_FUNCTIONS
801 /* Return the hot section for function DECL. Return text_section for
802 null DECLs. */
804 static section *
805 hot_function_section (tree decl)
807 if (decl != NULL_TREE
808 && DECL_SECTION_NAME (decl) != NULL_TREE
809 && targetm.have_named_sections)
810 return get_named_section (decl, NULL, 0);
811 else
812 return text_section;
814 #endif
816 /* Return the section for function DECL.
818 If DECL is NULL_TREE, return the text section. We can be passed
819 NULL_TREE under some circumstances by dbxout.c at least. */
821 section *
822 function_section (tree decl)
824 int reloc = 0;
826 if (first_function_block_is_cold)
827 reloc = 1;
829 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
830 if (decl != NULL_TREE
831 && DECL_SECTION_NAME (decl) != NULL_TREE)
832 return reloc ? unlikely_text_section ()
833 : get_named_section (decl, NULL, 0);
834 else
835 return targetm.asm_out.select_section (decl, reloc, DECL_ALIGN (decl));
836 #else
837 return reloc ? unlikely_text_section () : hot_function_section (decl);
838 #endif
841 section *
842 current_function_section (void)
844 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
845 if (current_function_decl != NULL_TREE
846 && DECL_SECTION_NAME (current_function_decl) != NULL_TREE)
847 return in_cold_section_p ? unlikely_text_section ()
848 : get_named_section (current_function_decl,
849 NULL, 0);
850 else
851 return targetm.asm_out.select_section (current_function_decl,
852 in_cold_section_p,
853 DECL_ALIGN (current_function_decl));
854 #else
855 return (in_cold_section_p
856 ? unlikely_text_section ()
857 : hot_function_section (current_function_decl));
858 #endif
861 /* Return the read-only data section associated with function DECL. */
863 section *
864 default_function_rodata_section (tree decl)
866 if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
868 const char *name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
870 if (DECL_ONE_ONLY (decl) && HAVE_COMDAT_GROUP)
872 size_t len = strlen (name) + 3;
873 char* rname = alloca (len);
875 strcpy (rname, ".rodata");
876 strcat (rname, name + 5);
877 return get_section (rname, SECTION_LINKONCE, decl);
879 /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo. */
880 else if (DECL_ONE_ONLY (decl)
881 && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
883 size_t len = strlen (name) + 1;
884 char *rname = alloca (len);
886 memcpy (rname, name, len);
887 rname[14] = 'r';
888 return get_section (rname, SECTION_LINKONCE, decl);
890 /* For .text.foo we want to use .rodata.foo. */
891 else if (flag_function_sections && flag_data_sections
892 && strncmp (name, ".text.", 6) == 0)
894 size_t len = strlen (name) + 1;
895 char *rname = alloca (len + 2);
897 memcpy (rname, ".rodata", 7);
898 memcpy (rname + 7, name + 5, len - 5);
899 return get_section (rname, 0, decl);
903 return readonly_data_section;
906 /* Return the read-only data section associated with function DECL
907 for targets where that section should be always the single
908 readonly data section. */
910 section *
911 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
913 return readonly_data_section;
916 /* Return the section to use for string merging. */
918 static section *
919 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
920 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
921 unsigned int flags ATTRIBUTE_UNUSED)
923 HOST_WIDE_INT len;
925 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
926 && TREE_CODE (decl) == STRING_CST
927 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
928 && align <= 256
929 && (len = int_size_in_bytes (TREE_TYPE (decl))) > 0
930 && TREE_STRING_LENGTH (decl) >= len)
932 enum machine_mode mode;
933 unsigned int modesize;
934 const char *str;
935 HOST_WIDE_INT i;
936 int j, unit;
937 char name[30];
939 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
940 modesize = GET_MODE_BITSIZE (mode);
941 if (modesize >= 8 && modesize <= 256
942 && (modesize & (modesize - 1)) == 0)
944 if (align < modesize)
945 align = modesize;
947 str = TREE_STRING_POINTER (decl);
948 unit = GET_MODE_SIZE (mode);
950 /* Check for embedded NUL characters. */
951 for (i = 0; i < len; i += unit)
953 for (j = 0; j < unit; j++)
954 if (str[i + j] != '\0')
955 break;
956 if (j == unit)
957 break;
959 if (i == len - unit)
961 sprintf (name, ".rodata.str%d.%d", modesize / 8,
962 (int) (align / 8));
963 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
964 return get_section (name, flags, NULL);
969 return readonly_data_section;
972 /* Return the section to use for constant merging. */
974 section *
975 mergeable_constant_section (enum machine_mode mode ATTRIBUTE_UNUSED,
976 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
977 unsigned int flags ATTRIBUTE_UNUSED)
979 unsigned int modesize = GET_MODE_BITSIZE (mode);
981 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
982 && mode != VOIDmode
983 && mode != BLKmode
984 && modesize <= align
985 && align >= 8
986 && align <= 256
987 && (align & (align - 1)) == 0)
989 char name[24];
991 sprintf (name, ".rodata.cst%d", (int) (align / 8));
992 flags |= (align / 8) | SECTION_MERGE;
993 return get_section (name, flags, NULL);
995 return readonly_data_section;
998 /* Given NAME, a putative register name, discard any customary prefixes. */
1000 static const char *
1001 strip_reg_name (const char *name)
1003 #ifdef REGISTER_PREFIX
1004 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
1005 name += strlen (REGISTER_PREFIX);
1006 #endif
1007 if (name[0] == '%' || name[0] == '#')
1008 name++;
1009 return name;
1012 /* The user has asked for a DECL to have a particular name. Set (or
1013 change) it in such a way that we don't prefix an underscore to
1014 it. */
1015 void
1016 set_user_assembler_name (tree decl, const char *name)
1018 char *starred = alloca (strlen (name) + 2);
1019 starred[0] = '*';
1020 strcpy (starred + 1, name);
1021 change_decl_assembler_name (decl, get_identifier (starred));
1022 SET_DECL_RTL (decl, NULL_RTX);
1025 /* Decode an `asm' spec for a declaration as a register name.
1026 Return the register number, or -1 if nothing specified,
1027 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
1028 or -3 if ASMSPEC is `cc' and is not recognized,
1029 or -4 if ASMSPEC is `memory' and is not recognized.
1030 Accept an exact spelling or a decimal number.
1031 Prefixes such as % are optional. */
1034 decode_reg_name (const char *asmspec)
1036 if (asmspec != 0)
1038 int i;
1040 /* Get rid of confusing prefixes. */
1041 asmspec = strip_reg_name (asmspec);
1043 /* Allow a decimal number as a "register name". */
1044 for (i = strlen (asmspec) - 1; i >= 0; i--)
1045 if (! ISDIGIT (asmspec[i]))
1046 break;
1047 if (asmspec[0] != 0 && i < 0)
1049 i = atoi (asmspec);
1050 if (i < FIRST_PSEUDO_REGISTER && i >= 0)
1051 return i;
1052 else
1053 return -2;
1056 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
1057 if (reg_names[i][0]
1058 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
1059 return i;
1061 #ifdef ADDITIONAL_REGISTER_NAMES
1063 static const struct { const char *const name; const int number; } table[]
1064 = ADDITIONAL_REGISTER_NAMES;
1066 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
1067 if (table[i].name[0]
1068 && ! strcmp (asmspec, table[i].name))
1069 return table[i].number;
1071 #endif /* ADDITIONAL_REGISTER_NAMES */
1073 if (!strcmp (asmspec, "memory"))
1074 return -4;
1076 if (!strcmp (asmspec, "cc"))
1077 return -3;
1079 return -2;
1082 return -1;
1085 /* Return true if DECL's initializer is suitable for a BSS section. */
1087 static bool
1088 bss_initializer_p (const_tree decl)
1090 return (DECL_INITIAL (decl) == NULL
1091 || DECL_INITIAL (decl) == error_mark_node
1092 || (flag_zero_initialized_in_bss
1093 /* Leave constant zeroes in .rodata so they
1094 can be shared. */
1095 && !TREE_READONLY (decl)
1096 && initializer_zerop (DECL_INITIAL (decl))));
1099 /* Compute the alignment of variable specified by DECL.
1100 DONT_OUTPUT_DATA is from assemble_variable. */
1102 void
1103 align_variable (tree decl, bool dont_output_data)
1105 unsigned int align = DECL_ALIGN (decl);
1107 /* In the case for initialing an array whose length isn't specified,
1108 where we have not yet been able to do the layout,
1109 figure out the proper alignment now. */
1110 if (dont_output_data && DECL_SIZE (decl) == 0
1111 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
1112 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
1114 /* Some object file formats have a maximum alignment which they support.
1115 In particular, a.out format supports a maximum alignment of 4. */
1116 if (align > MAX_OFILE_ALIGNMENT)
1118 warning (0, "alignment of %q+D is greater than maximum object "
1119 "file alignment. Using %d", decl,
1120 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
1121 align = MAX_OFILE_ALIGNMENT;
1124 /* On some machines, it is good to increase alignment sometimes. */
1125 if (! DECL_USER_ALIGN (decl))
1127 #ifdef DATA_ALIGNMENT
1128 unsigned int data_align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1129 /* Don't increase alignment too much for TLS variables - TLS space
1130 is too precious. */
1131 if (! DECL_THREAD_LOCAL_P (decl) || data_align <= BITS_PER_WORD)
1132 align = data_align;
1133 #endif
1134 #ifdef CONSTANT_ALIGNMENT
1135 if (DECL_INITIAL (decl) != 0 && DECL_INITIAL (decl) != error_mark_node)
1137 unsigned int const_align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl),
1138 align);
1139 /* Don't increase alignment too much for TLS variables - TLS space
1140 is too precious. */
1141 if (! DECL_THREAD_LOCAL_P (decl) || const_align <= BITS_PER_WORD)
1142 align = const_align;
1144 #endif
1147 /* Reset the alignment in case we have made it tighter, so we can benefit
1148 from it in get_pointer_alignment. */
1149 DECL_ALIGN (decl) = align;
1152 /* Return the section into which the given VAR_DECL or CONST_DECL
1153 should be placed. PREFER_NOSWITCH_P is true if a noswitch
1154 section should be used wherever possible. */
1156 static section *
1157 get_variable_section (tree decl, bool prefer_noswitch_p)
1159 int reloc;
1161 /* If the decl has been given an explicit section name, then it
1162 isn't common, and shouldn't be handled as such. */
1163 if (DECL_COMMON (decl) && DECL_SECTION_NAME (decl) == NULL)
1165 if (DECL_THREAD_LOCAL_P (decl))
1166 return tls_comm_section;
1167 /* This cannot be common bss for an emulated TLS object without
1168 a register_common hook. */
1169 else if (DECL_TLS_MODEL (decl) == TLS_MODEL_EMULATED
1170 && !targetm.emutls.register_common)
1172 else if (TREE_PUBLIC (decl) && bss_initializer_p (decl))
1173 return comm_section;
1176 if (DECL_INITIAL (decl) == error_mark_node)
1177 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1178 else if (DECL_INITIAL (decl))
1179 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1180 else
1181 reloc = 0;
1183 resolve_unique_section (decl, reloc, flag_data_sections);
1184 if (IN_NAMED_SECTION (decl))
1185 return get_named_section (decl, NULL, reloc);
1187 if (!DECL_THREAD_LOCAL_P (decl)
1188 && !(prefer_noswitch_p && targetm.have_switchable_bss_sections)
1189 && bss_initializer_p (decl))
1191 if (!TREE_PUBLIC (decl))
1192 return lcomm_section;
1193 if (bss_noswitch_section)
1194 return bss_noswitch_section;
1197 return targetm.asm_out.select_section (decl, reloc, DECL_ALIGN (decl));
1200 /* Return the block into which object_block DECL should be placed. */
1202 static struct object_block *
1203 get_block_for_decl (tree decl)
1205 section *sect;
1207 if (TREE_CODE (decl) == VAR_DECL)
1209 /* The object must be defined in this translation unit. */
1210 if (DECL_EXTERNAL (decl))
1211 return NULL;
1213 /* There's no point using object blocks for something that is
1214 isolated by definition. */
1215 if (DECL_ONE_ONLY (decl))
1216 return NULL;
1219 /* We can only calculate block offsets if the decl has a known
1220 constant size. */
1221 if (DECL_SIZE_UNIT (decl) == NULL)
1222 return NULL;
1223 if (!host_integerp (DECL_SIZE_UNIT (decl), 1))
1224 return NULL;
1226 /* Find out which section should contain DECL. We cannot put it into
1227 an object block if it requires a standalone definition. */
1228 if (TREE_CODE (decl) == VAR_DECL)
1229 align_variable (decl, 0);
1230 sect = get_variable_section (decl, true);
1231 if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
1232 return NULL;
1234 return get_block_for_section (sect);
1237 /* Make sure block symbol SYMBOL is in block BLOCK. */
1239 static void
1240 change_symbol_block (rtx symbol, struct object_block *block)
1242 if (block != SYMBOL_REF_BLOCK (symbol))
1244 gcc_assert (SYMBOL_REF_BLOCK_OFFSET (symbol) < 0);
1245 SYMBOL_REF_BLOCK (symbol) = block;
1249 /* Return true if it is possible to put DECL in an object_block. */
1251 static bool
1252 use_blocks_for_decl_p (tree decl)
1254 /* Only data DECLs can be placed into object blocks. */
1255 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != CONST_DECL)
1256 return false;
1258 /* Detect decls created by dw2_force_const_mem. Such decls are
1259 special because DECL_INITIAL doesn't specify the decl's true value.
1260 dw2_output_indirect_constants will instead call assemble_variable
1261 with dont_output_data set to 1 and then print the contents itself. */
1262 if (DECL_INITIAL (decl) == decl)
1263 return false;
1265 /* If this decl is an alias, then we don't want to emit a definition. */
1266 if (lookup_attribute ("alias", DECL_ATTRIBUTES (decl)))
1267 return false;
1269 return true;
1272 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
1273 have static storage duration. In other words, it should not be an
1274 automatic variable, including PARM_DECLs.
1276 There is, however, one exception: this function handles variables
1277 explicitly placed in a particular register by the user.
1279 This is never called for PARM_DECL nodes. */
1281 void
1282 make_decl_rtl (tree decl)
1284 const char *name = 0;
1285 int reg_number;
1286 rtx x;
1288 /* Check that we are not being given an automatic variable. */
1289 gcc_assert (TREE_CODE (decl) != PARM_DECL
1290 && TREE_CODE (decl) != RESULT_DECL);
1292 /* A weak alias has TREE_PUBLIC set but not the other bits. */
1293 gcc_assert (TREE_CODE (decl) != VAR_DECL
1294 || TREE_STATIC (decl)
1295 || TREE_PUBLIC (decl)
1296 || DECL_EXTERNAL (decl)
1297 || DECL_REGISTER (decl));
1299 /* And that we were not given a type or a label. */
1300 gcc_assert (TREE_CODE (decl) != TYPE_DECL
1301 && TREE_CODE (decl) != LABEL_DECL);
1303 /* For a duplicate declaration, we can be called twice on the
1304 same DECL node. Don't discard the RTL already made. */
1305 if (DECL_RTL_SET_P (decl))
1307 /* If the old RTL had the wrong mode, fix the mode. */
1308 x = DECL_RTL (decl);
1309 if (GET_MODE (x) != DECL_MODE (decl))
1310 SET_DECL_RTL (decl, adjust_address_nv (x, DECL_MODE (decl), 0));
1312 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1313 return;
1315 /* ??? Another way to do this would be to maintain a hashed
1316 table of such critters. Instead of adding stuff to a DECL
1317 to give certain attributes to it, we could use an external
1318 hash map from DECL to set of attributes. */
1320 /* Let the target reassign the RTL if it wants.
1321 This is necessary, for example, when one machine specific
1322 decl attribute overrides another. */
1323 targetm.encode_section_info (decl, DECL_RTL (decl), false);
1325 /* If the symbol has a SYMBOL_REF_BLOCK field, update it based
1326 on the new decl information. */
1327 if (MEM_P (x)
1328 && GET_CODE (XEXP (x, 0)) == SYMBOL_REF
1329 && SYMBOL_REF_HAS_BLOCK_INFO_P (XEXP (x, 0)))
1330 change_symbol_block (XEXP (x, 0), get_block_for_decl (decl));
1332 /* Make this function static known to the mudflap runtime. */
1333 if (flag_mudflap && TREE_CODE (decl) == VAR_DECL)
1334 mudflap_enqueue_decl (decl);
1336 return;
1339 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
1341 if (name[0] != '*' && TREE_CODE (decl) != FUNCTION_DECL
1342 && DECL_REGISTER (decl))
1344 error ("register name not specified for %q+D", decl);
1346 else if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
1348 const char *asmspec = name+1;
1349 reg_number = decode_reg_name (asmspec);
1350 /* First detect errors in declaring global registers. */
1351 if (reg_number == -1)
1352 error ("register name not specified for %q+D", decl);
1353 else if (reg_number < 0)
1354 error ("invalid register name for %q+D", decl);
1355 else if (TYPE_MODE (TREE_TYPE (decl)) == BLKmode)
1356 error ("data type of %q+D isn%'t suitable for a register",
1357 decl);
1358 else if (! HARD_REGNO_MODE_OK (reg_number, TYPE_MODE (TREE_TYPE (decl))))
1359 error ("register specified for %q+D isn%'t suitable for data type",
1360 decl);
1361 /* Now handle properly declared static register variables. */
1362 else
1364 int nregs;
1366 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
1368 DECL_INITIAL (decl) = 0;
1369 error ("global register variable has initial value");
1371 if (TREE_THIS_VOLATILE (decl))
1372 warning (OPT_Wvolatile_register_var,
1373 "optimization may eliminate reads and/or "
1374 "writes to register variables");
1376 /* If the user specified one of the eliminables registers here,
1377 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
1378 confused with that register and be eliminated. This usage is
1379 somewhat suspect... */
1381 SET_DECL_RTL (decl, gen_rtx_raw_REG (DECL_MODE (decl), reg_number));
1382 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
1383 REG_USERVAR_P (DECL_RTL (decl)) = 1;
1385 if (TREE_STATIC (decl))
1387 /* Make this register global, so not usable for anything
1388 else. */
1389 #ifdef ASM_DECLARE_REGISTER_GLOBAL
1390 name = IDENTIFIER_POINTER (DECL_NAME (decl));
1391 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
1392 #endif
1393 nregs = hard_regno_nregs[reg_number][DECL_MODE (decl)];
1394 while (nregs > 0)
1395 globalize_reg (reg_number + --nregs);
1398 /* As a register variable, it has no section. */
1399 return;
1402 /* Now handle ordinary static variables and functions (in memory).
1403 Also handle vars declared register invalidly. */
1404 else if (name[0] == '*')
1406 #ifdef REGISTER_PREFIX
1407 if (strlen (REGISTER_PREFIX) != 0)
1409 reg_number = decode_reg_name (name);
1410 if (reg_number >= 0 || reg_number == -3)
1411 error ("register name given for non-register variable %q+D", decl);
1413 #endif
1416 /* Specifying a section attribute on a variable forces it into a
1417 non-.bss section, and thus it cannot be common. */
1418 if (TREE_CODE (decl) == VAR_DECL
1419 && DECL_SECTION_NAME (decl) != NULL_TREE
1420 && DECL_INITIAL (decl) == NULL_TREE
1421 && DECL_COMMON (decl))
1422 DECL_COMMON (decl) = 0;
1424 /* Variables can't be both common and weak. */
1425 if (TREE_CODE (decl) == VAR_DECL && DECL_WEAK (decl))
1426 DECL_COMMON (decl) = 0;
1428 if (use_object_blocks_p () && use_blocks_for_decl_p (decl))
1429 x = create_block_symbol (name, get_block_for_decl (decl), -1);
1430 else
1431 x = gen_rtx_SYMBOL_REF (Pmode, name);
1432 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
1433 SET_SYMBOL_REF_DECL (x, decl);
1435 x = gen_rtx_MEM (DECL_MODE (decl), x);
1436 if (TREE_CODE (decl) != FUNCTION_DECL)
1437 set_mem_attributes (x, decl, 1);
1438 SET_DECL_RTL (decl, x);
1440 /* Optionally set flags or add text to the name to record information
1441 such as that it is a function name.
1442 If the name is changed, the macro ASM_OUTPUT_LABELREF
1443 will have to know how to strip this information. */
1444 targetm.encode_section_info (decl, DECL_RTL (decl), true);
1446 /* Make this function static known to the mudflap runtime. */
1447 if (flag_mudflap && TREE_CODE (decl) == VAR_DECL)
1448 mudflap_enqueue_decl (decl);
1451 /* Output a string of literal assembler code
1452 for an `asm' keyword used between functions. */
1454 void
1455 assemble_asm (tree string)
1457 app_enable ();
1459 if (TREE_CODE (string) == ADDR_EXPR)
1460 string = TREE_OPERAND (string, 0);
1462 fprintf (asm_out_file, "\t%s\n", TREE_STRING_POINTER (string));
1465 /* Record an element in the table of global destructors. SYMBOL is
1466 a SYMBOL_REF of the function to be called; PRIORITY is a number
1467 between 0 and MAX_INIT_PRIORITY. */
1469 void
1470 default_stabs_asm_out_destructor (rtx symbol ATTRIBUTE_UNUSED,
1471 int priority ATTRIBUTE_UNUSED)
1473 #if defined DBX_DEBUGGING_INFO || defined XCOFF_DEBUGGING_INFO
1474 /* Tell GNU LD that this is part of the static destructor set.
1475 This will work for any system that uses stabs, most usefully
1476 aout systems. */
1477 dbxout_begin_simple_stabs ("___DTOR_LIST__", 22 /* N_SETT */);
1478 dbxout_stab_value_label (XSTR (symbol, 0));
1479 #else
1480 sorry ("global destructors not supported on this target");
1481 #endif
1484 /* Write the address of the entity given by SYMBOL to SEC. */
1485 void
1486 assemble_addr_to_section (rtx symbol, section *sec)
1488 switch_to_section (sec);
1489 assemble_align (POINTER_SIZE);
1490 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1493 /* Return the numbered .ctors.N (if CONSTRUCTOR_P) or .dtors.N (if
1494 not) section for PRIORITY. */
1495 section *
1496 get_cdtor_priority_section (int priority, bool constructor_p)
1498 char buf[16];
1500 /* ??? This only works reliably with the GNU linker. */
1501 sprintf (buf, "%s.%.5u",
1502 constructor_p ? ".ctors" : ".dtors",
1503 /* Invert the numbering so the linker puts us in the proper
1504 order; constructors are run from right to left, and the
1505 linker sorts in increasing order. */
1506 MAX_INIT_PRIORITY - priority);
1507 return get_section (buf, SECTION_WRITE, NULL);
1510 void
1511 default_named_section_asm_out_destructor (rtx symbol, int priority)
1513 section *sec;
1515 if (priority != DEFAULT_INIT_PRIORITY)
1516 sec = get_cdtor_priority_section (priority,
1517 /*constructor_p=*/false);
1518 else
1519 sec = get_section (".dtors", SECTION_WRITE, NULL);
1521 assemble_addr_to_section (symbol, sec);
1524 #ifdef DTORS_SECTION_ASM_OP
1525 void
1526 default_dtor_section_asm_out_destructor (rtx symbol,
1527 int priority ATTRIBUTE_UNUSED)
1529 assemble_addr_to_section (symbol, dtors_section);
1531 #endif
1533 /* Likewise for global constructors. */
1535 void
1536 default_stabs_asm_out_constructor (rtx symbol ATTRIBUTE_UNUSED,
1537 int priority ATTRIBUTE_UNUSED)
1539 #if defined DBX_DEBUGGING_INFO || defined XCOFF_DEBUGGING_INFO
1540 /* Tell GNU LD that this is part of the static destructor set.
1541 This will work for any system that uses stabs, most usefully
1542 aout systems. */
1543 dbxout_begin_simple_stabs ("___CTOR_LIST__", 22 /* N_SETT */);
1544 dbxout_stab_value_label (XSTR (symbol, 0));
1545 #else
1546 sorry ("global constructors not supported on this target");
1547 #endif
1550 void
1551 default_named_section_asm_out_constructor (rtx symbol, int priority)
1553 section *sec;
1555 if (priority != DEFAULT_INIT_PRIORITY)
1556 sec = get_cdtor_priority_section (priority,
1557 /*constructor_p=*/true);
1558 else
1559 sec = get_section (".ctors", SECTION_WRITE, NULL);
1561 assemble_addr_to_section (symbol, sec);
1564 #ifdef CTORS_SECTION_ASM_OP
1565 void
1566 default_ctor_section_asm_out_constructor (rtx symbol,
1567 int priority ATTRIBUTE_UNUSED)
1569 assemble_addr_to_section (symbol, ctors_section);
1571 #endif
1573 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1574 a nonzero value if the constant pool should be output before the
1575 start of the function, or a zero value if the pool should output
1576 after the end of the function. The default is to put it before the
1577 start. */
1579 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1580 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1581 #endif
1583 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1584 to be output to assembler.
1585 Set first_global_object_name and weak_global_object_name as appropriate. */
1587 void
1588 notice_global_symbol (tree decl)
1590 const char **type = &first_global_object_name;
1592 if (first_global_object_name
1593 || !TREE_PUBLIC (decl)
1594 || DECL_EXTERNAL (decl)
1595 || !DECL_NAME (decl)
1596 || (TREE_CODE (decl) != FUNCTION_DECL
1597 && (TREE_CODE (decl) != VAR_DECL
1598 || (DECL_COMMON (decl)
1599 && (DECL_INITIAL (decl) == 0
1600 || DECL_INITIAL (decl) == error_mark_node))))
1601 || !MEM_P (DECL_RTL (decl)))
1602 return;
1604 /* We win when global object is found, but it is useful to know about weak
1605 symbol as well so we can produce nicer unique names. */
1606 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl) || flag_shlib)
1607 type = &weak_global_object_name;
1609 if (!*type)
1611 const char *p;
1612 const char *name;
1613 rtx decl_rtl = DECL_RTL (decl);
1615 p = targetm.strip_name_encoding (XSTR (XEXP (decl_rtl, 0), 0));
1616 name = ggc_strdup (p);
1618 *type = name;
1622 /* Output assembler code for the constant pool of a function and associated
1623 with defining the name of the function. DECL describes the function.
1624 NAME is the function's name. For the constant pool, we use the current
1625 constant pool data. */
1627 void
1628 assemble_start_function (tree decl, const char *fnname)
1630 int align;
1631 char tmp_label[100];
1632 bool hot_label_written = false;
1634 crtl->subsections.unlikely_text_section_name = NULL;
1636 first_function_block_is_cold = false;
1637 if (flag_reorder_blocks_and_partition)
1639 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTB", const_labelno);
1640 crtl->subsections.hot_section_label = ggc_strdup (tmp_label);
1641 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDB", const_labelno);
1642 crtl->subsections.cold_section_label = ggc_strdup (tmp_label);
1643 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LHOTE", const_labelno);
1644 crtl->subsections.hot_section_end_label = ggc_strdup (tmp_label);
1645 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "LCOLDE", const_labelno);
1646 crtl->subsections.cold_section_end_label = ggc_strdup (tmp_label);
1647 const_labelno++;
1649 else
1651 crtl->subsections.hot_section_label = NULL;
1652 crtl->subsections.cold_section_label = NULL;
1653 crtl->subsections.hot_section_end_label = NULL;
1654 crtl->subsections.cold_section_end_label = NULL;
1657 /* The following code does not need preprocessing in the assembler. */
1659 app_disable ();
1661 if (CONSTANT_POOL_BEFORE_FUNCTION)
1662 output_constant_pool (fnname, decl);
1664 resolve_unique_section (decl, 0, flag_function_sections);
1666 /* Make sure the not and cold text (code) sections are properly
1667 aligned. This is necessary here in the case where the function
1668 has both hot and cold sections, because we don't want to re-set
1669 the alignment when the section switch happens mid-function. */
1671 if (flag_reorder_blocks_and_partition)
1673 switch_to_section (unlikely_text_section ());
1674 assemble_align (DECL_ALIGN (decl));
1675 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_label);
1677 /* When the function starts with a cold section, we need to explicitly
1678 align the hot section and write out the hot section label.
1679 But if the current function is a thunk, we do not have a CFG. */
1680 if (!crtl->is_thunk
1681 && BB_PARTITION (ENTRY_BLOCK_PTR->next_bb) == BB_COLD_PARTITION)
1683 switch_to_section (text_section);
1684 assemble_align (DECL_ALIGN (decl));
1685 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1686 hot_label_written = true;
1687 first_function_block_is_cold = true;
1690 else if (DECL_SECTION_NAME (decl))
1692 /* Calls to function_section rely on first_function_block_is_cold
1693 being accurate. The first block may be cold even if we aren't
1694 doing partitioning, if the entire function was decided by
1695 choose_function_section (predict.c) to be cold. */
1697 initialize_cold_section_name ();
1699 if (crtl->subsections.unlikely_text_section_name
1700 && strcmp (TREE_STRING_POINTER (DECL_SECTION_NAME (decl)),
1701 crtl->subsections.unlikely_text_section_name) == 0)
1702 first_function_block_is_cold = true;
1705 in_cold_section_p = first_function_block_is_cold;
1707 /* Switch to the correct text section for the start of the function. */
1709 switch_to_section (function_section (decl));
1710 if (flag_reorder_blocks_and_partition
1711 && !hot_label_written)
1712 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_label);
1714 /* Tell assembler to move to target machine's alignment for functions. */
1715 align = floor_log2 (DECL_ALIGN (decl) / BITS_PER_UNIT);
1716 if (align > 0)
1718 ASM_OUTPUT_ALIGN (asm_out_file, align);
1721 /* Handle a user-specified function alignment.
1722 Note that we still need to align to DECL_ALIGN, as above,
1723 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1724 if (! DECL_USER_ALIGN (decl)
1725 && align_functions_log > align
1726 && cfun->function_frequency != FUNCTION_FREQUENCY_UNLIKELY_EXECUTED)
1728 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1729 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1730 align_functions_log, align_functions - 1);
1731 #else
1732 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1733 #endif
1736 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1737 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1738 #endif
1740 (*debug_hooks->begin_function) (decl);
1742 /* Make function name accessible from other files, if appropriate. */
1744 if (TREE_PUBLIC (decl))
1746 notice_global_symbol (decl);
1748 globalize_decl (decl);
1750 maybe_assemble_visibility (decl);
1753 if (DECL_PRESERVE_P (decl))
1754 targetm.asm_out.mark_decl_preserved (fnname);
1756 /* Do any machine/system dependent processing of the function name. */
1757 #ifdef ASM_DECLARE_FUNCTION_NAME
1758 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1759 #else
1760 /* Standard thing is just output label for the function. */
1761 ASM_OUTPUT_LABEL (asm_out_file, fnname);
1762 #endif /* ASM_DECLARE_FUNCTION_NAME */
1765 /* Output assembler code associated with defining the size of the
1766 function. DECL describes the function. NAME is the function's name. */
1768 void
1769 assemble_end_function (tree decl, const char *fnname ATTRIBUTE_UNUSED)
1771 #ifdef ASM_DECLARE_FUNCTION_SIZE
1772 /* We could have switched section in the middle of the function. */
1773 if (flag_reorder_blocks_and_partition)
1774 switch_to_section (function_section (decl));
1775 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1776 #endif
1777 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1779 output_constant_pool (fnname, decl);
1780 switch_to_section (function_section (decl)); /* need to switch back */
1782 /* Output labels for end of hot/cold text sections (to be used by
1783 debug info.) */
1784 if (flag_reorder_blocks_and_partition)
1786 section *save_text_section;
1788 save_text_section = in_section;
1789 switch_to_section (unlikely_text_section ());
1790 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.cold_section_end_label);
1791 if (first_function_block_is_cold)
1792 switch_to_section (text_section);
1793 else
1794 switch_to_section (function_section (decl));
1795 ASM_OUTPUT_LABEL (asm_out_file, crtl->subsections.hot_section_end_label);
1796 switch_to_section (save_text_section);
1800 /* Assemble code to leave SIZE bytes of zeros. */
1802 void
1803 assemble_zeros (unsigned HOST_WIDE_INT size)
1805 /* Do no output if -fsyntax-only. */
1806 if (flag_syntax_only)
1807 return;
1809 #ifdef ASM_NO_SKIP_IN_TEXT
1810 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1811 so we must output 0s explicitly in the text section. */
1812 if (ASM_NO_SKIP_IN_TEXT && (in_section->common.flags & SECTION_CODE) != 0)
1814 unsigned HOST_WIDE_INT i;
1815 for (i = 0; i < size; i++)
1816 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1818 else
1819 #endif
1820 if (size > 0)
1821 ASM_OUTPUT_SKIP (asm_out_file, size);
1824 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1826 void
1827 assemble_align (int align)
1829 if (align > BITS_PER_UNIT)
1831 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1835 /* Assemble a string constant with the specified C string as contents. */
1837 void
1838 assemble_string (const char *p, int size)
1840 int pos = 0;
1841 int maximum = 2000;
1843 /* If the string is very long, split it up. */
1845 while (pos < size)
1847 int thissize = size - pos;
1848 if (thissize > maximum)
1849 thissize = maximum;
1851 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1853 pos += thissize;
1854 p += thissize;
1859 /* A noswitch_section_callback for lcomm_section. */
1861 static bool
1862 emit_local (tree decl ATTRIBUTE_UNUSED,
1863 const char *name ATTRIBUTE_UNUSED,
1864 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1865 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1867 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1868 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name,
1869 size, DECL_ALIGN (decl));
1870 return true;
1871 #elif defined ASM_OUTPUT_ALIGNED_LOCAL
1872 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, DECL_ALIGN (decl));
1873 return true;
1874 #else
1875 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1876 return false;
1877 #endif
1880 /* A noswitch_section_callback for bss_noswitch_section. */
1882 #if defined ASM_OUTPUT_ALIGNED_BSS || defined ASM_OUTPUT_BSS
1883 static bool
1884 emit_bss (tree decl ATTRIBUTE_UNUSED,
1885 const char *name ATTRIBUTE_UNUSED,
1886 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1887 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1889 #if defined ASM_OUTPUT_ALIGNED_BSS
1890 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size, DECL_ALIGN (decl));
1891 return true;
1892 #else
1893 ASM_OUTPUT_BSS (asm_out_file, decl, name, size, rounded);
1894 return false;
1895 #endif
1897 #endif
1899 /* A noswitch_section_callback for comm_section. */
1901 static bool
1902 emit_common (tree decl ATTRIBUTE_UNUSED,
1903 const char *name ATTRIBUTE_UNUSED,
1904 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1905 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1907 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1908 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name,
1909 size, DECL_ALIGN (decl));
1910 return true;
1911 #elif defined ASM_OUTPUT_ALIGNED_COMMON
1912 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size, DECL_ALIGN (decl));
1913 return true;
1914 #else
1915 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
1916 return false;
1917 #endif
1920 /* A noswitch_section_callback for tls_comm_section. */
1922 static bool
1923 emit_tls_common (tree decl ATTRIBUTE_UNUSED,
1924 const char *name ATTRIBUTE_UNUSED,
1925 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1926 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1928 #ifdef ASM_OUTPUT_TLS_COMMON
1929 ASM_OUTPUT_TLS_COMMON (asm_out_file, decl, name, size);
1930 return true;
1931 #else
1932 sorry ("thread-local COMMON data not implemented");
1933 return true;
1934 #endif
1937 /* Assemble DECL given that it belongs in SECTION_NOSWITCH section SECT.
1938 NAME is the name of DECL's SYMBOL_REF. */
1940 static void
1941 assemble_noswitch_variable (tree decl, const char *name, section *sect)
1943 unsigned HOST_WIDE_INT size, rounded;
1945 size = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
1946 rounded = size;
1948 /* Don't allocate zero bytes of common,
1949 since that means "undefined external" in the linker. */
1950 if (size == 0)
1951 rounded = 1;
1953 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1954 so that each uninitialized object starts on such a boundary. */
1955 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
1956 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1957 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1959 if (!sect->noswitch.callback (decl, name, size, rounded)
1960 && (unsigned HOST_WIDE_INT) DECL_ALIGN_UNIT (decl) > rounded)
1961 warning (0, "requested alignment for %q+D is greater than "
1962 "implemented alignment of %wu", decl, rounded);
1965 /* A subroutine of assemble_variable. Output the label and contents of
1966 DECL, whose address is a SYMBOL_REF with name NAME. DONT_OUTPUT_DATA
1967 is as for assemble_variable. */
1969 static void
1970 assemble_variable_contents (tree decl, const char *name,
1971 bool dont_output_data)
1973 /* Do any machine/system dependent processing of the object. */
1974 #ifdef ASM_DECLARE_OBJECT_NAME
1975 last_assemble_variable_decl = decl;
1976 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
1977 #else
1978 /* Standard thing is just output label for the object. */
1979 ASM_OUTPUT_LABEL (asm_out_file, name);
1980 #endif /* ASM_DECLARE_OBJECT_NAME */
1982 if (!dont_output_data)
1984 if (DECL_INITIAL (decl)
1985 && DECL_INITIAL (decl) != error_mark_node
1986 && !initializer_zerop (DECL_INITIAL (decl)))
1987 /* Output the actual data. */
1988 output_constant (DECL_INITIAL (decl),
1989 tree_low_cst (DECL_SIZE_UNIT (decl), 1),
1990 DECL_ALIGN (decl));
1991 else
1992 /* Leave space for it. */
1993 assemble_zeros (tree_low_cst (DECL_SIZE_UNIT (decl), 1));
1997 /* Initialize emulated tls object TO, which refers to TLS variable
1998 DECL and is initialized by PROXY. */
2000 tree
2001 default_emutls_var_init (tree to, tree decl, tree proxy)
2003 VEC(constructor_elt,gc) *v = VEC_alloc (constructor_elt, gc, 4);
2004 constructor_elt *elt;
2005 tree type = TREE_TYPE (to);
2006 tree field = TYPE_FIELDS (type);
2008 elt = VEC_quick_push (constructor_elt, v, NULL);
2009 elt->index = field;
2010 elt->value = fold_convert (TREE_TYPE (field), DECL_SIZE_UNIT (decl));
2012 elt = VEC_quick_push (constructor_elt, v, NULL);
2013 field = TREE_CHAIN (field);
2014 elt->index = field;
2015 elt->value = build_int_cst (TREE_TYPE (field),
2016 DECL_ALIGN_UNIT (decl));
2018 elt = VEC_quick_push (constructor_elt, v, NULL);
2019 field = TREE_CHAIN (field);
2020 elt->index = field;
2021 elt->value = null_pointer_node;
2023 elt = VEC_quick_push (constructor_elt, v, NULL);
2024 field = TREE_CHAIN (field);
2025 elt->index = field;
2026 elt->value = proxy;
2028 return build_constructor (type, v);
2031 /* Assemble everything that is needed for a variable or function declaration.
2032 Not used for automatic variables, and not used for function definitions.
2033 Should not be called for variables of incomplete structure type.
2035 TOP_LEVEL is nonzero if this variable has file scope.
2036 AT_END is nonzero if this is the special handling, at end of compilation,
2037 to define things that have had only tentative definitions.
2038 DONT_OUTPUT_DATA if nonzero means don't actually output the
2039 initial value (that will be done by the caller). */
2041 void
2042 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
2043 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
2045 const char *name;
2046 rtx decl_rtl, symbol;
2047 section *sect;
2049 if (! targetm.have_tls
2050 && TREE_CODE (decl) == VAR_DECL
2051 && DECL_THREAD_LOCAL_P (decl))
2053 tree to = emutls_decl (decl);
2055 /* If this variable is defined locally, then we need to initialize the
2056 control structure with size and alignment information. We do this
2057 at the last moment because tentative definitions can take a locally
2058 defined but uninitialized variable and initialize it later, which
2059 would result in incorrect contents. */
2060 if (! DECL_EXTERNAL (to)
2061 && (! DECL_COMMON (to)
2062 || (DECL_INITIAL (decl)
2063 && DECL_INITIAL (decl) != error_mark_node)))
2065 DECL_INITIAL (to) = targetm.emutls.var_init
2066 (to, decl, get_emutls_init_templ_addr (decl));
2068 /* Make sure the template is marked as needed early enough.
2069 Without this, if the variable is placed in a
2070 section-anchored block, the template will only be marked
2071 when it's too late. */
2072 record_references_in_initializer (to);
2075 decl = to;
2078 last_assemble_variable_decl = 0;
2080 /* Normally no need to say anything here for external references,
2081 since assemble_external is called by the language-specific code
2082 when a declaration is first seen. */
2084 if (DECL_EXTERNAL (decl))
2085 return;
2087 /* Output no assembler code for a function declaration.
2088 Only definitions of functions output anything. */
2090 if (TREE_CODE (decl) == FUNCTION_DECL)
2091 return;
2093 /* Do nothing for global register variables. */
2094 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
2096 TREE_ASM_WRITTEN (decl) = 1;
2097 return;
2100 /* If type was incomplete when the variable was declared,
2101 see if it is complete now. */
2103 if (DECL_SIZE (decl) == 0)
2104 layout_decl (decl, 0);
2106 /* Still incomplete => don't allocate it; treat the tentative defn
2107 (which is what it must have been) as an `extern' reference. */
2109 if (!dont_output_data && DECL_SIZE (decl) == 0)
2111 error ("storage size of %q+D isn%'t known", decl);
2112 TREE_ASM_WRITTEN (decl) = 1;
2113 return;
2116 /* The first declaration of a variable that comes through this function
2117 decides whether it is global (in C, has external linkage)
2118 or local (in C, has internal linkage). So do nothing more
2119 if this function has already run. */
2121 if (TREE_ASM_WRITTEN (decl))
2122 return;
2124 /* Make sure targetm.encode_section_info is invoked before we set
2125 ASM_WRITTEN. */
2126 decl_rtl = DECL_RTL (decl);
2128 TREE_ASM_WRITTEN (decl) = 1;
2130 /* Do no output if -fsyntax-only. */
2131 if (flag_syntax_only)
2132 return;
2134 app_disable ();
2136 if (! dont_output_data
2137 && ! host_integerp (DECL_SIZE_UNIT (decl), 1))
2139 error ("size of variable %q+D is too large", decl);
2140 return;
2143 gcc_assert (MEM_P (decl_rtl));
2144 gcc_assert (GET_CODE (XEXP (decl_rtl, 0)) == SYMBOL_REF);
2145 symbol = XEXP (decl_rtl, 0);
2146 name = XSTR (symbol, 0);
2147 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
2148 notice_global_symbol (decl);
2150 /* Compute the alignment of this data. */
2152 align_variable (decl, dont_output_data);
2153 set_mem_align (decl_rtl, DECL_ALIGN (decl));
2155 if (TREE_PUBLIC (decl))
2156 maybe_assemble_visibility (decl);
2158 if (DECL_PRESERVE_P (decl))
2159 targetm.asm_out.mark_decl_preserved (name);
2161 /* First make the assembler name(s) global if appropriate. */
2162 sect = get_variable_section (decl, false);
2163 if (TREE_PUBLIC (decl)
2164 && DECL_NAME (decl)
2165 && (sect->common.flags & SECTION_COMMON) == 0)
2166 globalize_decl (decl);
2168 /* Output any data that we will need to use the address of. */
2169 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
2170 output_addressed_constants (DECL_INITIAL (decl));
2172 /* dbxout.c needs to know this. */
2173 if (sect && (sect->common.flags & SECTION_CODE) != 0)
2174 DECL_IN_TEXT_SECTION (decl) = 1;
2176 /* If the decl is part of an object_block, make sure that the decl
2177 has been positioned within its block, but do not write out its
2178 definition yet. output_object_blocks will do that later. */
2179 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
2181 gcc_assert (!dont_output_data);
2182 place_block_symbol (symbol);
2184 else if (SECTION_STYLE (sect) == SECTION_NOSWITCH)
2185 assemble_noswitch_variable (decl, name, sect);
2186 else
2188 switch_to_section (sect);
2189 if (DECL_ALIGN (decl) > BITS_PER_UNIT)
2190 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (DECL_ALIGN_UNIT (decl)));
2191 assemble_variable_contents (decl, name, dont_output_data);
2195 /* Return 1 if type TYPE contains any pointers. */
2197 static int
2198 contains_pointers_p (tree type)
2200 switch (TREE_CODE (type))
2202 case POINTER_TYPE:
2203 case REFERENCE_TYPE:
2204 /* I'm not sure whether OFFSET_TYPE needs this treatment,
2205 so I'll play safe and return 1. */
2206 case OFFSET_TYPE:
2207 return 1;
2209 case RECORD_TYPE:
2210 case UNION_TYPE:
2211 case QUAL_UNION_TYPE:
2213 tree fields;
2214 /* For a type that has fields, see if the fields have pointers. */
2215 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
2216 if (TREE_CODE (fields) == FIELD_DECL
2217 && contains_pointers_p (TREE_TYPE (fields)))
2218 return 1;
2219 return 0;
2222 case ARRAY_TYPE:
2223 /* An array type contains pointers if its element type does. */
2224 return contains_pointers_p (TREE_TYPE (type));
2226 default:
2227 return 0;
2231 /* In unit-at-a-time mode, we delay assemble_external processing until
2232 the compilation unit is finalized. This is the best we can do for
2233 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
2234 it all the way to final. See PR 17982 for further discussion. */
2235 static GTY(()) tree pending_assemble_externals;
2237 #ifdef ASM_OUTPUT_EXTERNAL
2238 /* True if DECL is a function decl for which no out-of-line copy exists.
2239 It is assumed that DECL's assembler name has been set. */
2241 static bool
2242 incorporeal_function_p (tree decl)
2244 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
2246 const char *name;
2248 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
2249 && DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA)
2250 return true;
2252 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
2253 if (strncmp (name, "__builtin_", strlen ("__builtin_")) == 0)
2254 return true;
2256 return false;
2259 /* Actually do the tests to determine if this is necessary, and invoke
2260 ASM_OUTPUT_EXTERNAL. */
2261 static void
2262 assemble_external_real (tree decl)
2264 rtx rtl = DECL_RTL (decl);
2266 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
2267 && !SYMBOL_REF_USED (XEXP (rtl, 0))
2268 && !incorporeal_function_p (decl))
2270 /* Some systems do require some output. */
2271 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
2272 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
2275 #endif
2277 void
2278 process_pending_assemble_externals (void)
2280 #ifdef ASM_OUTPUT_EXTERNAL
2281 tree list;
2282 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
2283 assemble_external_real (TREE_VALUE (list));
2285 pending_assemble_externals = 0;
2286 #endif
2289 /* Output something to declare an external symbol to the assembler.
2290 (Most assemblers don't need this, so we normally output nothing.)
2291 Do nothing if DECL is not external. */
2293 void
2294 assemble_external (tree decl ATTRIBUTE_UNUSED)
2296 /* Because most platforms do not define ASM_OUTPUT_EXTERNAL, the
2297 main body of this code is only rarely exercised. To provide some
2298 testing, on all platforms, we make sure that the ASM_OUT_FILE is
2299 open. If it's not, we should not be calling this function. */
2300 gcc_assert (asm_out_file);
2302 #ifdef ASM_OUTPUT_EXTERNAL
2303 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
2304 return;
2306 /* We want to output external symbols at very last to check if they
2307 are references or not. */
2308 pending_assemble_externals = tree_cons (0, decl,
2309 pending_assemble_externals);
2310 #endif
2313 /* Similar, for calling a library function FUN. */
2315 void
2316 assemble_external_libcall (rtx fun)
2318 /* Declare library function name external when first used, if nec. */
2319 if (! SYMBOL_REF_USED (fun))
2321 SYMBOL_REF_USED (fun) = 1;
2322 targetm.asm_out.external_libcall (fun);
2326 /* Assemble a label named NAME. */
2328 void
2329 assemble_label (const char *name)
2331 ASM_OUTPUT_LABEL (asm_out_file, name);
2334 /* Set the symbol_referenced flag for ID. */
2335 void
2336 mark_referenced (tree id)
2338 TREE_SYMBOL_REFERENCED (id) = 1;
2341 /* Set the symbol_referenced flag for DECL and notify callgraph. */
2342 void
2343 mark_decl_referenced (tree decl)
2345 if (TREE_CODE (decl) == FUNCTION_DECL)
2347 /* Extern inline functions don't become needed when referenced.
2348 If we know a method will be emitted in other TU and no new
2349 functions can be marked reachable, just use the external
2350 definition. */
2351 struct cgraph_node *node = cgraph_node (decl);
2352 if (!DECL_EXTERNAL (decl)
2353 && (!node->local.vtable_method || !cgraph_global_info_ready
2354 || !node->local.finalized))
2355 cgraph_mark_needed_node (node);
2357 else if (TREE_CODE (decl) == VAR_DECL)
2359 struct varpool_node *node = varpool_node (decl);
2360 varpool_mark_needed_node (node);
2361 /* C++ frontend use mark_decl_references to force COMDAT variables
2362 to be output that might appear dead otherwise. */
2363 node->force_output = true;
2365 /* else do nothing - we can get various sorts of CST nodes here,
2366 which do not need to be marked. */
2370 /* Follow the IDENTIFIER_TRANSPARENT_ALIAS chain starting at *ALIAS
2371 until we find an identifier that is not itself a transparent alias.
2372 Modify the alias passed to it by reference (and all aliases on the
2373 way to the ultimate target), such that they do not have to be
2374 followed again, and return the ultimate target of the alias
2375 chain. */
2377 static inline tree
2378 ultimate_transparent_alias_target (tree *alias)
2380 tree target = *alias;
2382 if (IDENTIFIER_TRANSPARENT_ALIAS (target))
2384 gcc_assert (TREE_CHAIN (target));
2385 target = ultimate_transparent_alias_target (&TREE_CHAIN (target));
2386 gcc_assert (! IDENTIFIER_TRANSPARENT_ALIAS (target)
2387 && ! TREE_CHAIN (target));
2388 *alias = target;
2391 return target;
2394 /* Output to FILE (an assembly file) a reference to NAME. If NAME
2395 starts with a *, the rest of NAME is output verbatim. Otherwise
2396 NAME is transformed in a target-specific way (usually by the
2397 addition of an underscore). */
2399 void
2400 assemble_name_raw (FILE *file, const char *name)
2402 if (name[0] == '*')
2403 fputs (&name[1], file);
2404 else
2405 ASM_OUTPUT_LABELREF (file, name);
2408 /* Like assemble_name_raw, but should be used when NAME might refer to
2409 an entity that is also represented as a tree (like a function or
2410 variable). If NAME does refer to such an entity, that entity will
2411 be marked as referenced. */
2413 void
2414 assemble_name (FILE *file, const char *name)
2416 const char *real_name;
2417 tree id;
2419 real_name = targetm.strip_name_encoding (name);
2421 id = maybe_get_identifier (real_name);
2422 if (id)
2424 tree id_orig = id;
2426 mark_referenced (id);
2427 ultimate_transparent_alias_target (&id);
2428 if (id != id_orig)
2429 name = IDENTIFIER_POINTER (id);
2430 gcc_assert (! TREE_CHAIN (id));
2433 assemble_name_raw (file, name);
2436 /* Allocate SIZE bytes writable static space with a gensym name
2437 and return an RTX to refer to its address. */
2440 assemble_static_space (unsigned HOST_WIDE_INT size)
2442 char name[12];
2443 const char *namestring;
2444 rtx x;
2446 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2447 ++const_labelno;
2448 namestring = ggc_strdup (name);
2450 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2451 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2453 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2454 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2455 BIGGEST_ALIGNMENT);
2456 #else
2457 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2458 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2459 #else
2461 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2462 so that each uninitialized object starts on such a boundary. */
2463 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2464 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2465 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2466 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2467 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2468 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2470 #endif
2471 #endif
2472 return x;
2475 /* Assemble the static constant template for function entry trampolines.
2476 This is done at most once per compilation.
2477 Returns an RTX for the address of the template. */
2479 static GTY(()) rtx initial_trampoline;
2481 #ifdef TRAMPOLINE_TEMPLATE
2483 assemble_trampoline_template (void)
2485 char label[256];
2486 const char *name;
2487 int align;
2488 rtx symbol;
2490 if (initial_trampoline)
2491 return initial_trampoline;
2493 /* By default, put trampoline templates in read-only data section. */
2495 #ifdef TRAMPOLINE_SECTION
2496 switch_to_section (TRAMPOLINE_SECTION);
2497 #else
2498 switch_to_section (readonly_data_section);
2499 #endif
2501 /* Write the assembler code to define one. */
2502 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2503 if (align > 0)
2505 ASM_OUTPUT_ALIGN (asm_out_file, align);
2508 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2509 TRAMPOLINE_TEMPLATE (asm_out_file);
2511 /* Record the rtl to refer to it. */
2512 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2513 name = ggc_strdup (label);
2514 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2515 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2517 initial_trampoline = gen_rtx_MEM (BLKmode, symbol);
2518 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2520 return initial_trampoline;
2522 #endif
2524 /* A and B are either alignments or offsets. Return the minimum alignment
2525 that may be assumed after adding the two together. */
2527 static inline unsigned
2528 min_align (unsigned int a, unsigned int b)
2530 return (a | b) & -(a | b);
2533 /* Return the assembler directive for creating a given kind of integer
2534 object. SIZE is the number of bytes in the object and ALIGNED_P
2535 indicates whether it is known to be aligned. Return NULL if the
2536 assembly dialect has no such directive.
2538 The returned string should be printed at the start of a new line and
2539 be followed immediately by the object's initial value. */
2541 const char *
2542 integer_asm_op (int size, int aligned_p)
2544 struct asm_int_op *ops;
2546 if (aligned_p)
2547 ops = &targetm.asm_out.aligned_op;
2548 else
2549 ops = &targetm.asm_out.unaligned_op;
2551 switch (size)
2553 case 1:
2554 return targetm.asm_out.byte_op;
2555 case 2:
2556 return ops->hi;
2557 case 4:
2558 return ops->si;
2559 case 8:
2560 return ops->di;
2561 case 16:
2562 return ops->ti;
2563 default:
2564 return NULL;
2568 /* Use directive OP to assemble an integer object X. Print OP at the
2569 start of the line, followed immediately by the value of X. */
2571 void
2572 assemble_integer_with_op (const char *op, rtx x)
2574 fputs (op, asm_out_file);
2575 output_addr_const (asm_out_file, x);
2576 fputc ('\n', asm_out_file);
2579 /* The default implementation of the asm_out.integer target hook. */
2581 bool
2582 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2583 unsigned int size ATTRIBUTE_UNUSED,
2584 int aligned_p ATTRIBUTE_UNUSED)
2586 const char *op = integer_asm_op (size, aligned_p);
2587 /* Avoid GAS bugs for large values. Specifically negative values whose
2588 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2589 if (size > UNITS_PER_WORD && size > POINTER_SIZE / BITS_PER_UNIT)
2590 return false;
2591 return op && (assemble_integer_with_op (op, x), true);
2594 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2595 the alignment of the integer in bits. Return 1 if we were able to output
2596 the constant, otherwise 0. We must be able to output the constant,
2597 if FORCE is nonzero. */
2599 bool
2600 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2602 int aligned_p;
2604 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2606 /* See if the target hook can handle this kind of object. */
2607 if (targetm.asm_out.integer (x, size, aligned_p))
2608 return true;
2610 /* If the object is a multi-byte one, try splitting it up. Split
2611 it into words it if is multi-word, otherwise split it into bytes. */
2612 if (size > 1)
2614 enum machine_mode omode, imode;
2615 unsigned int subalign;
2616 unsigned int subsize, i;
2617 unsigned char mclass;
2619 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2620 subalign = MIN (align, subsize * BITS_PER_UNIT);
2621 if (GET_CODE (x) == CONST_FIXED)
2622 mclass = GET_MODE_CLASS (GET_MODE (x));
2623 else
2624 mclass = MODE_INT;
2626 omode = mode_for_size (subsize * BITS_PER_UNIT, mclass, 0);
2627 imode = mode_for_size (size * BITS_PER_UNIT, mclass, 0);
2629 for (i = 0; i < size; i += subsize)
2631 rtx partial = simplify_subreg (omode, x, imode, i);
2632 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2633 break;
2635 if (i == size)
2636 return true;
2638 /* If we've printed some of it, but not all of it, there's no going
2639 back now. */
2640 gcc_assert (!i);
2643 gcc_assert (!force);
2645 return false;
2648 void
2649 assemble_real (REAL_VALUE_TYPE d, enum machine_mode mode, unsigned int align)
2651 long data[4] = {0, 0, 0, 0};
2652 int i;
2653 int bitsize, nelts, nunits, units_per;
2655 /* This is hairy. We have a quantity of known size. real_to_target
2656 will put it into an array of *host* longs, 32 bits per element
2657 (even if long is more than 32 bits). We need to determine the
2658 number of array elements that are occupied (nelts) and the number
2659 of *target* min-addressable units that will be occupied in the
2660 object file (nunits). We cannot assume that 32 divides the
2661 mode's bitsize (size * BITS_PER_UNIT) evenly.
2663 size * BITS_PER_UNIT is used here to make sure that padding bits
2664 (which might appear at either end of the value; real_to_target
2665 will include the padding bits in its output array) are included. */
2667 nunits = GET_MODE_SIZE (mode);
2668 bitsize = nunits * BITS_PER_UNIT;
2669 nelts = CEIL (bitsize, 32);
2670 units_per = 32 / BITS_PER_UNIT;
2672 real_to_target (data, &d, mode);
2674 /* Put out the first word with the specified alignment. */
2675 assemble_integer (GEN_INT (data[0]), MIN (nunits, units_per), align, 1);
2676 nunits -= units_per;
2678 /* Subsequent words need only 32-bit alignment. */
2679 align = min_align (align, 32);
2681 for (i = 1; i < nelts; i++)
2683 assemble_integer (GEN_INT (data[i]), MIN (nunits, units_per), align, 1);
2684 nunits -= units_per;
2688 /* Given an expression EXP with a constant value,
2689 reduce it to the sum of an assembler symbol and an integer.
2690 Store them both in the structure *VALUE.
2691 EXP must be reducible. */
2693 struct addr_const GTY(())
2695 rtx base;
2696 HOST_WIDE_INT offset;
2699 static void
2700 decode_addr_const (tree exp, struct addr_const *value)
2702 tree target = TREE_OPERAND (exp, 0);
2703 int offset = 0;
2704 rtx x;
2706 while (1)
2708 if (TREE_CODE (target) == COMPONENT_REF
2709 && host_integerp (byte_position (TREE_OPERAND (target, 1)), 0))
2712 offset += int_byte_position (TREE_OPERAND (target, 1));
2713 target = TREE_OPERAND (target, 0);
2715 else if (TREE_CODE (target) == ARRAY_REF
2716 || TREE_CODE (target) == ARRAY_RANGE_REF)
2718 offset += (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (target)), 1)
2719 * tree_low_cst (TREE_OPERAND (target, 1), 0));
2720 target = TREE_OPERAND (target, 0);
2722 else
2723 break;
2726 switch (TREE_CODE (target))
2728 case VAR_DECL:
2729 case FUNCTION_DECL:
2730 x = DECL_RTL (target);
2731 break;
2733 case LABEL_DECL:
2734 x = gen_rtx_MEM (FUNCTION_MODE,
2735 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2736 break;
2738 case REAL_CST:
2739 case FIXED_CST:
2740 case STRING_CST:
2741 case COMPLEX_CST:
2742 case CONSTRUCTOR:
2743 case INTEGER_CST:
2744 x = output_constant_def (target, 1);
2745 break;
2747 default:
2748 gcc_unreachable ();
2751 gcc_assert (MEM_P (x));
2752 x = XEXP (x, 0);
2754 value->base = x;
2755 value->offset = offset;
2758 /* Uniquize all constants that appear in memory.
2759 Each constant in memory thus far output is recorded
2760 in `const_desc_table'. */
2762 struct constant_descriptor_tree GTY(())
2764 /* A MEM for the constant. */
2765 rtx rtl;
2767 /* The value of the constant. */
2768 tree value;
2770 /* Hash of value. Computing the hash from value each time
2771 hashfn is called can't work properly, as that means recursive
2772 use of the hash table during hash table expansion. */
2773 hashval_t hash;
2776 static GTY((param_is (struct constant_descriptor_tree)))
2777 htab_t const_desc_htab;
2779 static struct constant_descriptor_tree * build_constant_desc (tree);
2780 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2782 /* Compute a hash code for a constant expression. */
2784 static hashval_t
2785 const_desc_hash (const void *ptr)
2787 return ((const struct constant_descriptor_tree *)ptr)->hash;
2790 static hashval_t
2791 const_hash_1 (const tree exp)
2793 const char *p;
2794 hashval_t hi;
2795 int len, i;
2796 enum tree_code code = TREE_CODE (exp);
2798 /* Either set P and LEN to the address and len of something to hash and
2799 exit the switch or return a value. */
2801 switch (code)
2803 case INTEGER_CST:
2804 p = (char *) &TREE_INT_CST (exp);
2805 len = sizeof TREE_INT_CST (exp);
2806 break;
2808 case REAL_CST:
2809 return real_hash (TREE_REAL_CST_PTR (exp));
2811 case FIXED_CST:
2812 return fixed_hash (TREE_FIXED_CST_PTR (exp));
2814 case STRING_CST:
2815 p = TREE_STRING_POINTER (exp);
2816 len = TREE_STRING_LENGTH (exp);
2817 break;
2819 case COMPLEX_CST:
2820 return (const_hash_1 (TREE_REALPART (exp)) * 5
2821 + const_hash_1 (TREE_IMAGPART (exp)));
2823 case CONSTRUCTOR:
2825 unsigned HOST_WIDE_INT idx;
2826 tree value;
2828 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2830 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, value)
2831 if (value)
2832 hi = hi * 603 + const_hash_1 (value);
2834 return hi;
2837 case ADDR_EXPR:
2838 case FDESC_EXPR:
2840 struct addr_const value;
2842 decode_addr_const (exp, &value);
2843 switch (GET_CODE (value.base))
2845 case SYMBOL_REF:
2846 /* Don't hash the address of the SYMBOL_REF;
2847 only use the offset and the symbol name. */
2848 hi = value.offset;
2849 p = XSTR (value.base, 0);
2850 for (i = 0; p[i] != 0; i++)
2851 hi = ((hi * 613) + (unsigned) (p[i]));
2852 break;
2854 case LABEL_REF:
2855 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13;
2856 break;
2858 default:
2859 gcc_unreachable ();
2862 return hi;
2864 case PLUS_EXPR:
2865 case POINTER_PLUS_EXPR:
2866 case MINUS_EXPR:
2867 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2868 + const_hash_1 (TREE_OPERAND (exp, 1)));
2870 case NOP_EXPR:
2871 case CONVERT_EXPR:
2872 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
2874 default:
2875 /* A language specific constant. Just hash the code. */
2876 return code;
2879 /* Compute hashing function. */
2880 hi = len;
2881 for (i = 0; i < len; i++)
2882 hi = ((hi * 613) + (unsigned) (p[i]));
2884 return hi;
2887 /* Wrapper of compare_constant, for the htab interface. */
2888 static int
2889 const_desc_eq (const void *p1, const void *p2)
2891 const struct constant_descriptor_tree *c1 = p1;
2892 const struct constant_descriptor_tree *c2 = p2;
2893 if (c1->hash != c2->hash)
2894 return 0;
2895 return compare_constant (c1->value, c2->value);
2898 /* Compare t1 and t2, and return 1 only if they are known to result in
2899 the same bit pattern on output. */
2901 static int
2902 compare_constant (const tree t1, const tree t2)
2904 enum tree_code typecode;
2906 if (t1 == NULL_TREE)
2907 return t2 == NULL_TREE;
2908 if (t2 == NULL_TREE)
2909 return 0;
2911 if (TREE_CODE (t1) != TREE_CODE (t2))
2912 return 0;
2914 switch (TREE_CODE (t1))
2916 case INTEGER_CST:
2917 /* Integer constants are the same only if the same width of type. */
2918 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2919 return 0;
2920 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2921 return 0;
2922 return tree_int_cst_equal (t1, t2);
2924 case REAL_CST:
2925 /* Real constants are the same only if the same width of type. */
2926 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2927 return 0;
2929 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
2931 case FIXED_CST:
2932 /* Fixed constants are the same only if the same width of type. */
2933 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2934 return 0;
2936 return FIXED_VALUES_IDENTICAL (TREE_FIXED_CST (t1), TREE_FIXED_CST (t2));
2938 case STRING_CST:
2939 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2940 return 0;
2942 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
2943 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
2944 TREE_STRING_LENGTH (t1)));
2946 case COMPLEX_CST:
2947 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
2948 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
2950 case CONSTRUCTOR:
2952 VEC(constructor_elt, gc) *v1, *v2;
2953 unsigned HOST_WIDE_INT idx;
2955 typecode = TREE_CODE (TREE_TYPE (t1));
2956 if (typecode != TREE_CODE (TREE_TYPE (t2)))
2957 return 0;
2959 if (typecode == ARRAY_TYPE)
2961 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
2962 /* For arrays, check that the sizes all match. */
2963 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
2964 || size_1 == -1
2965 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
2966 return 0;
2968 else
2970 /* For record and union constructors, require exact type
2971 equality. */
2972 if (TREE_TYPE (t1) != TREE_TYPE (t2))
2973 return 0;
2976 v1 = CONSTRUCTOR_ELTS (t1);
2977 v2 = CONSTRUCTOR_ELTS (t2);
2978 if (VEC_length (constructor_elt, v1)
2979 != VEC_length (constructor_elt, v2))
2980 return 0;
2982 for (idx = 0; idx < VEC_length (constructor_elt, v1); ++idx)
2984 constructor_elt *c1 = VEC_index (constructor_elt, v1, idx);
2985 constructor_elt *c2 = VEC_index (constructor_elt, v2, idx);
2987 /* Check that each value is the same... */
2988 if (!compare_constant (c1->value, c2->value))
2989 return 0;
2990 /* ... and that they apply to the same fields! */
2991 if (typecode == ARRAY_TYPE)
2993 if (!compare_constant (c1->index, c2->index))
2994 return 0;
2996 else
2998 if (c1->index != c2->index)
2999 return 0;
3003 return 1;
3006 case ADDR_EXPR:
3007 case FDESC_EXPR:
3009 struct addr_const value1, value2;
3011 decode_addr_const (t1, &value1);
3012 decode_addr_const (t2, &value2);
3013 return (value1.offset == value2.offset
3014 && strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
3017 case PLUS_EXPR:
3018 case POINTER_PLUS_EXPR:
3019 case MINUS_EXPR:
3020 case RANGE_EXPR:
3021 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
3022 && compare_constant(TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
3024 case NOP_EXPR:
3025 case CONVERT_EXPR:
3026 case VIEW_CONVERT_EXPR:
3027 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
3029 default:
3030 return 0;
3033 gcc_unreachable ();
3036 /* Make a copy of the whole tree structure for a constant. This
3037 handles the same types of nodes that compare_constant handles. */
3039 static tree
3040 copy_constant (tree exp)
3042 switch (TREE_CODE (exp))
3044 case ADDR_EXPR:
3045 /* For ADDR_EXPR, we do not want to copy the decl whose address
3046 is requested. We do want to copy constants though. */
3047 if (CONSTANT_CLASS_P (TREE_OPERAND (exp, 0)))
3048 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
3049 copy_constant (TREE_OPERAND (exp, 0)));
3050 else
3051 return copy_node (exp);
3053 case INTEGER_CST:
3054 case REAL_CST:
3055 case FIXED_CST:
3056 case STRING_CST:
3057 return copy_node (exp);
3059 case COMPLEX_CST:
3060 return build_complex (TREE_TYPE (exp),
3061 copy_constant (TREE_REALPART (exp)),
3062 copy_constant (TREE_IMAGPART (exp)));
3064 case PLUS_EXPR:
3065 case POINTER_PLUS_EXPR:
3066 case MINUS_EXPR:
3067 return build2 (TREE_CODE (exp), TREE_TYPE (exp),
3068 copy_constant (TREE_OPERAND (exp, 0)),
3069 copy_constant (TREE_OPERAND (exp, 1)));
3071 case NOP_EXPR:
3072 case CONVERT_EXPR:
3073 case VIEW_CONVERT_EXPR:
3074 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
3075 copy_constant (TREE_OPERAND (exp, 0)));
3077 case CONSTRUCTOR:
3079 tree copy = copy_node (exp);
3080 VEC(constructor_elt, gc) *v;
3081 unsigned HOST_WIDE_INT idx;
3082 tree purpose, value;
3084 v = VEC_alloc(constructor_elt, gc, VEC_length(constructor_elt,
3085 CONSTRUCTOR_ELTS (exp)));
3086 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (exp), idx, purpose, value)
3088 constructor_elt *ce = VEC_quick_push (constructor_elt, v, NULL);
3089 ce->index = purpose;
3090 ce->value = copy_constant (value);
3092 CONSTRUCTOR_ELTS (copy) = v;
3093 return copy;
3096 default:
3097 gcc_unreachable ();
3101 /* Return the alignment of constant EXP in bits. */
3103 static unsigned int
3104 get_constant_alignment (tree exp)
3106 unsigned int align;
3108 align = TYPE_ALIGN (TREE_TYPE (exp));
3109 #ifdef CONSTANT_ALIGNMENT
3110 align = CONSTANT_ALIGNMENT (exp, align);
3111 #endif
3112 return align;
3115 /* Return the section into which constant EXP should be placed. */
3117 static section *
3118 get_constant_section (tree exp)
3120 if (IN_NAMED_SECTION (exp))
3121 return get_named_section (exp, NULL, compute_reloc_for_constant (exp));
3122 else
3123 return targetm.asm_out.select_section (exp,
3124 compute_reloc_for_constant (exp),
3125 get_constant_alignment (exp));
3128 /* Return the size of constant EXP in bytes. */
3130 static HOST_WIDE_INT
3131 get_constant_size (tree exp)
3133 HOST_WIDE_INT size;
3135 size = int_size_in_bytes (TREE_TYPE (exp));
3136 if (TREE_CODE (exp) == STRING_CST)
3137 size = MAX (TREE_STRING_LENGTH (exp), size);
3138 return size;
3141 /* Subroutine of output_constant_def:
3142 No constant equal to EXP is known to have been output.
3143 Make a constant descriptor to enter EXP in the hash table.
3144 Assign the label number and construct RTL to refer to the
3145 constant's location in memory.
3146 Caller is responsible for updating the hash table. */
3148 static struct constant_descriptor_tree *
3149 build_constant_desc (tree exp)
3151 rtx symbol;
3152 rtx rtl;
3153 char label[256];
3154 int labelno;
3155 struct constant_descriptor_tree *desc;
3157 desc = ggc_alloc (sizeof (*desc));
3158 desc->value = copy_constant (exp);
3160 /* Propagate marked-ness to copied constant. */
3161 if (flag_mudflap && mf_marked_p (exp))
3162 mf_mark (desc->value);
3164 /* Create a string containing the label name, in LABEL. */
3165 labelno = const_labelno++;
3166 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
3168 /* We have a symbol name; construct the SYMBOL_REF and the MEM. */
3169 if (use_object_blocks_p ())
3171 section *sect = get_constant_section (exp);
3172 symbol = create_block_symbol (ggc_strdup (label),
3173 get_block_for_section (sect), -1);
3175 else
3176 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3177 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3178 SET_SYMBOL_REF_DECL (symbol, desc->value);
3179 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3181 rtl = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)), symbol);
3182 set_mem_attributes (rtl, exp, 1);
3183 set_mem_alias_set (rtl, 0);
3184 set_mem_alias_set (rtl, const_alias_set);
3186 /* Set flags or add text to the name to record information, such as
3187 that it is a local symbol. If the name is changed, the macro
3188 ASM_OUTPUT_LABELREF will have to know how to strip this
3189 information. This call might invalidate our local variable
3190 SYMBOL; we can't use it afterward. */
3192 targetm.encode_section_info (exp, rtl, true);
3194 desc->rtl = rtl;
3196 return desc;
3199 /* Return an rtx representing a reference to constant data in memory
3200 for the constant expression EXP.
3202 If assembler code for such a constant has already been output,
3203 return an rtx to refer to it.
3204 Otherwise, output such a constant in memory
3205 and generate an rtx for it.
3207 If DEFER is nonzero, this constant can be deferred and output only
3208 if referenced in the function after all optimizations.
3210 `const_desc_table' records which constants already have label strings. */
3213 output_constant_def (tree exp, int defer)
3215 struct constant_descriptor_tree *desc;
3216 struct constant_descriptor_tree key;
3217 void **loc;
3219 /* Look up EXP in the table of constant descriptors. If we didn't find
3220 it, create a new one. */
3221 key.value = exp;
3222 key.hash = const_hash_1 (exp);
3223 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
3225 desc = *loc;
3226 if (desc == 0)
3228 desc = build_constant_desc (exp);
3229 desc->hash = key.hash;
3230 *loc = desc;
3233 maybe_output_constant_def_contents (desc, defer);
3234 return desc->rtl;
3237 /* Subroutine of output_constant_def: Decide whether or not we need to
3238 output the constant DESC now, and if so, do it. */
3239 static void
3240 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
3241 int defer)
3243 rtx symbol = XEXP (desc->rtl, 0);
3244 tree exp = desc->value;
3246 if (flag_syntax_only)
3247 return;
3249 if (TREE_ASM_WRITTEN (exp))
3250 /* Already output; don't do it again. */
3251 return;
3253 /* We can always defer constants as long as the context allows
3254 doing so. */
3255 if (defer)
3257 /* Increment n_deferred_constants if it exists. It needs to be at
3258 least as large as the number of constants actually referred to
3259 by the function. If it's too small we'll stop looking too early
3260 and fail to emit constants; if it's too large we'll only look
3261 through the entire function when we could have stopped earlier. */
3262 if (cfun)
3263 n_deferred_constants++;
3264 return;
3267 output_constant_def_contents (symbol);
3270 /* Subroutine of output_constant_def_contents. Output the definition
3271 of constant EXP, which is pointed to by label LABEL. ALIGN is the
3272 constant's alignment in bits. */
3274 static void
3275 assemble_constant_contents (tree exp, const char *label, unsigned int align)
3277 HOST_WIDE_INT size;
3279 size = get_constant_size (exp);
3281 /* Do any machine/system dependent processing of the constant. */
3282 #ifdef ASM_DECLARE_CONSTANT_NAME
3283 ASM_DECLARE_CONSTANT_NAME (asm_out_file, label, exp, size);
3284 #else
3285 /* Standard thing is just output label for the constant. */
3286 ASM_OUTPUT_LABEL (asm_out_file, label);
3287 #endif /* ASM_DECLARE_CONSTANT_NAME */
3289 /* Output the value of EXP. */
3290 output_constant (exp, size, align);
3293 /* We must output the constant data referred to by SYMBOL; do so. */
3295 static void
3296 output_constant_def_contents (rtx symbol)
3298 tree exp = SYMBOL_REF_DECL (symbol);
3299 unsigned int align;
3301 /* Make sure any other constants whose addresses appear in EXP
3302 are assigned label numbers. */
3303 output_addressed_constants (exp);
3305 /* We are no longer deferring this constant. */
3306 TREE_ASM_WRITTEN (exp) = 1;
3308 /* If the constant is part of an object block, make sure that the
3309 decl has been positioned within its block, but do not write out
3310 its definition yet. output_object_blocks will do that later. */
3311 if (SYMBOL_REF_HAS_BLOCK_INFO_P (symbol) && SYMBOL_REF_BLOCK (symbol))
3312 place_block_symbol (symbol);
3313 else
3315 switch_to_section (get_constant_section (exp));
3316 align = get_constant_alignment (exp);
3317 if (align > BITS_PER_UNIT)
3318 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
3319 assemble_constant_contents (exp, XSTR (symbol, 0), align);
3321 if (flag_mudflap)
3322 mudflap_enqueue_constant (exp);
3325 /* Look up EXP in the table of constant descriptors. Return the rtl
3326 if it has been emitted, else null. */
3329 lookup_constant_def (tree exp)
3331 struct constant_descriptor_tree *desc;
3332 struct constant_descriptor_tree key;
3334 key.value = exp;
3335 key.hash = const_hash_1 (exp);
3336 desc = htab_find_with_hash (const_desc_htab, &key, key.hash);
3338 return (desc ? desc->rtl : NULL_RTX);
3341 /* Used in the hash tables to avoid outputting the same constant
3342 twice. Unlike 'struct constant_descriptor_tree', RTX constants
3343 are output once per function, not once per file. */
3344 /* ??? Only a few targets need per-function constant pools. Most
3345 can use one per-file pool. Should add a targetm bit to tell the
3346 difference. */
3348 struct rtx_constant_pool GTY(())
3350 /* Pointers to first and last constant in pool, as ordered by offset. */
3351 struct constant_descriptor_rtx *first;
3352 struct constant_descriptor_rtx *last;
3354 /* Hash facility for making memory-constants from constant rtl-expressions.
3355 It is used on RISC machines where immediate integer arguments and
3356 constant addresses are restricted so that such constants must be stored
3357 in memory. */
3358 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_htab;
3360 /* Current offset in constant pool (does not include any
3361 machine-specific header). */
3362 HOST_WIDE_INT offset;
3365 struct constant_descriptor_rtx GTY((chain_next ("%h.next")))
3367 struct constant_descriptor_rtx *next;
3368 rtx mem;
3369 rtx sym;
3370 rtx constant;
3371 HOST_WIDE_INT offset;
3372 hashval_t hash;
3373 enum machine_mode mode;
3374 unsigned int align;
3375 int labelno;
3376 int mark;
3379 /* Hash and compare functions for const_rtx_htab. */
3381 static hashval_t
3382 const_desc_rtx_hash (const void *ptr)
3384 const struct constant_descriptor_rtx *desc = ptr;
3385 return desc->hash;
3388 static int
3389 const_desc_rtx_eq (const void *a, const void *b)
3391 const struct constant_descriptor_rtx *x = a;
3392 const struct constant_descriptor_rtx *y = b;
3394 if (x->mode != y->mode)
3395 return 0;
3396 return rtx_equal_p (x->constant, y->constant);
3399 /* This is the worker function for const_rtx_hash, called via for_each_rtx. */
3401 static int
3402 const_rtx_hash_1 (rtx *xp, void *data)
3404 unsigned HOST_WIDE_INT hwi;
3405 enum machine_mode mode;
3406 enum rtx_code code;
3407 hashval_t h, *hp;
3408 rtx x;
3410 x = *xp;
3411 code = GET_CODE (x);
3412 mode = GET_MODE (x);
3413 h = (hashval_t) code * 1048573 + mode;
3415 switch (code)
3417 case CONST_INT:
3418 hwi = INTVAL (x);
3419 fold_hwi:
3421 const int shift = sizeof (hashval_t) * CHAR_BIT;
3422 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
3423 int i;
3425 h ^= (hashval_t) hwi;
3426 for (i = 1; i < n; ++i)
3428 hwi >>= shift;
3429 h ^= (hashval_t) hwi;
3432 break;
3434 case CONST_DOUBLE:
3435 if (mode == VOIDmode)
3437 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
3438 goto fold_hwi;
3440 else
3441 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
3442 break;
3444 case CONST_FIXED:
3445 h ^= fixed_hash (CONST_FIXED_VALUE (x));
3446 break;
3448 case CONST_VECTOR:
3450 int i;
3451 for (i = XVECLEN (x, 0); i-- > 0; )
3452 h = h * 251 + const_rtx_hash_1 (&XVECEXP (x, 0, i), data);
3454 break;
3456 case SYMBOL_REF:
3457 h ^= htab_hash_string (XSTR (x, 0));
3458 break;
3460 case LABEL_REF:
3461 h = h * 251 + CODE_LABEL_NUMBER (XEXP (x, 0));
3462 break;
3464 case UNSPEC:
3465 case UNSPEC_VOLATILE:
3466 h = h * 251 + XINT (x, 1);
3467 break;
3469 default:
3470 break;
3473 hp = data;
3474 *hp = *hp * 509 + h;
3475 return 0;
3478 /* Compute a hash value for X, which should be a constant. */
3480 static hashval_t
3481 const_rtx_hash (rtx x)
3483 hashval_t h = 0;
3484 for_each_rtx (&x, const_rtx_hash_1, &h);
3485 return h;
3489 /* Create and return a new rtx constant pool. */
3491 static struct rtx_constant_pool *
3492 create_constant_pool (void)
3494 struct rtx_constant_pool *pool;
3496 pool = ggc_alloc (sizeof (struct rtx_constant_pool));
3497 pool->const_rtx_htab = htab_create_ggc (31, const_desc_rtx_hash,
3498 const_desc_rtx_eq, NULL);
3499 pool->first = NULL;
3500 pool->last = NULL;
3501 pool->offset = 0;
3502 return pool;
3505 /* Initialize constant pool hashing for a new function. */
3507 void
3508 init_varasm_status (void)
3510 crtl->varasm.pool = create_constant_pool ();
3511 crtl->varasm.deferred_constants = 0;
3514 /* Given a MINUS expression, simplify it if both sides
3515 include the same symbol. */
3518 simplify_subtraction (rtx x)
3520 rtx r = simplify_rtx (x);
3521 return r ? r : x;
3524 /* Given a constant rtx X, make (or find) a memory constant for its value
3525 and return a MEM rtx to refer to it in memory. */
3528 force_const_mem (enum machine_mode mode, rtx x)
3530 struct constant_descriptor_rtx *desc, tmp;
3531 struct rtx_constant_pool *pool;
3532 char label[256];
3533 rtx def, symbol;
3534 hashval_t hash;
3535 unsigned int align;
3536 void **slot;
3538 /* If we're not allowed to drop X into the constant pool, don't. */
3539 if (targetm.cannot_force_const_mem (x))
3540 return NULL_RTX;
3542 /* Record that this function has used a constant pool entry. */
3543 crtl->uses_const_pool = 1;
3545 /* Decide which pool to use. */
3546 pool = (targetm.use_blocks_for_constant_p (mode, x)
3547 ? shared_constant_pool
3548 : crtl->varasm.pool);
3550 /* Lookup the value in the hashtable. */
3551 tmp.constant = x;
3552 tmp.mode = mode;
3553 hash = const_rtx_hash (x);
3554 slot = htab_find_slot_with_hash (pool->const_rtx_htab, &tmp, hash, INSERT);
3555 desc = *slot;
3557 /* If the constant was already present, return its memory. */
3558 if (desc)
3559 return copy_rtx (desc->mem);
3561 /* Otherwise, create a new descriptor. */
3562 desc = ggc_alloc (sizeof (*desc));
3563 *slot = desc;
3565 /* Align the location counter as required by EXP's data type. */
3566 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3567 #ifdef CONSTANT_ALIGNMENT
3569 tree type = lang_hooks.types.type_for_mode (mode, 0);
3570 if (type != NULL_TREE)
3571 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3573 #endif
3575 pool->offset += (align / BITS_PER_UNIT) - 1;
3576 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3578 desc->next = NULL;
3579 desc->constant = tmp.constant;
3580 desc->offset = pool->offset;
3581 desc->hash = hash;
3582 desc->mode = mode;
3583 desc->align = align;
3584 desc->labelno = const_labelno;
3585 desc->mark = 0;
3587 pool->offset += GET_MODE_SIZE (mode);
3588 if (pool->last)
3589 pool->last->next = desc;
3590 else
3591 pool->first = pool->last = desc;
3592 pool->last = desc;
3594 /* Create a string containing the label name, in LABEL. */
3595 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3596 ++const_labelno;
3598 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3599 the constants pool. */
3600 if (use_object_blocks_p () && targetm.use_blocks_for_constant_p (mode, x))
3602 section *sect = targetm.asm_out.select_rtx_section (mode, x, align);
3603 symbol = create_block_symbol (ggc_strdup (label),
3604 get_block_for_section (sect), -1);
3606 else
3607 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3608 desc->sym = symbol;
3609 SYMBOL_REF_FLAGS (symbol) |= SYMBOL_FLAG_LOCAL;
3610 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3611 SET_SYMBOL_REF_CONSTANT (symbol, desc);
3613 /* Construct the MEM. */
3614 desc->mem = def = gen_const_mem (mode, symbol);
3615 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3616 set_mem_align (def, align);
3618 /* If we're dropping a label to the constant pool, make sure we
3619 don't delete it. */
3620 if (GET_CODE (x) == LABEL_REF)
3621 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3623 return copy_rtx (def);
3626 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3629 get_pool_constant (rtx addr)
3631 return SYMBOL_REF_CONSTANT (addr)->constant;
3634 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3635 and whether it has been output or not. */
3638 get_pool_constant_mark (rtx addr, bool *pmarked)
3640 struct constant_descriptor_rtx *desc;
3642 desc = SYMBOL_REF_CONSTANT (addr);
3643 *pmarked = (desc->mark != 0);
3644 return desc->constant;
3647 /* Similar, return the mode. */
3649 enum machine_mode
3650 get_pool_mode (const_rtx addr)
3652 return SYMBOL_REF_CONSTANT (addr)->mode;
3655 /* Return the size of the constant pool. */
3658 get_pool_size (void)
3660 return crtl->varasm.pool->offset;
3663 /* Worker function for output_constant_pool_1. Emit assembly for X
3664 in MODE with known alignment ALIGN. */
3666 static void
3667 output_constant_pool_2 (enum machine_mode mode, rtx x, unsigned int align)
3669 switch (GET_MODE_CLASS (mode))
3671 case MODE_FLOAT:
3672 case MODE_DECIMAL_FLOAT:
3674 REAL_VALUE_TYPE r;
3676 gcc_assert (GET_CODE (x) == CONST_DOUBLE);
3677 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3678 assemble_real (r, mode, align);
3679 break;
3682 case MODE_INT:
3683 case MODE_PARTIAL_INT:
3684 case MODE_FRACT:
3685 case MODE_UFRACT:
3686 case MODE_ACCUM:
3687 case MODE_UACCUM:
3688 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3689 break;
3691 case MODE_VECTOR_FLOAT:
3692 case MODE_VECTOR_INT:
3693 case MODE_VECTOR_FRACT:
3694 case MODE_VECTOR_UFRACT:
3695 case MODE_VECTOR_ACCUM:
3696 case MODE_VECTOR_UACCUM:
3698 int i, units;
3699 enum machine_mode submode = GET_MODE_INNER (mode);
3700 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3702 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3703 units = CONST_VECTOR_NUNITS (x);
3705 for (i = 0; i < units; i++)
3707 rtx elt = CONST_VECTOR_ELT (x, i);
3708 output_constant_pool_2 (submode, elt, i ? subalign : align);
3711 break;
3713 default:
3714 gcc_unreachable ();
3718 /* Worker function for output_constant_pool. Emit constant DESC,
3719 giving it ALIGN bits of alignment. */
3721 static void
3722 output_constant_pool_1 (struct constant_descriptor_rtx *desc,
3723 unsigned int align)
3725 rtx x, tmp;
3727 x = desc->constant;
3729 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3730 whose CODE_LABEL has been deleted. This can occur if a jump table
3731 is eliminated by optimization. If so, write a constant of zero
3732 instead. Note that this can also happen by turning the
3733 CODE_LABEL into a NOTE. */
3734 /* ??? This seems completely and utterly wrong. Certainly it's
3735 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3736 functioning even with INSN_DELETED_P and friends. */
3738 tmp = x;
3739 switch (GET_CODE (tmp))
3741 case CONST:
3742 if (GET_CODE (XEXP (tmp, 0)) != PLUS
3743 || GET_CODE (XEXP (XEXP (tmp, 0), 0)) != LABEL_REF)
3744 break;
3745 tmp = XEXP (XEXP (tmp, 0), 0);
3746 /* FALLTHRU */
3748 case LABEL_REF:
3749 tmp = XEXP (tmp, 0);
3750 gcc_assert (!INSN_DELETED_P (tmp));
3751 gcc_assert (!NOTE_P (tmp)
3752 || NOTE_KIND (tmp) != NOTE_INSN_DELETED);
3753 break;
3755 default:
3756 break;
3759 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3760 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3761 align, desc->labelno, done);
3762 #endif
3764 assemble_align (align);
3766 /* Output the label. */
3767 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3769 /* Output the data. */
3770 output_constant_pool_2 (desc->mode, x, align);
3772 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3773 sections have proper size. */
3774 if (align > GET_MODE_BITSIZE (desc->mode)
3775 && in_section
3776 && (in_section->common.flags & SECTION_MERGE))
3777 assemble_align (align);
3779 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3780 done:
3781 #endif
3782 return;
3785 /* Given a SYMBOL_REF CURRENT_RTX, mark it and all constants it refers
3786 to as used. Emit referenced deferred strings. This function can
3787 be used with for_each_rtx to mark all SYMBOL_REFs in an rtx. */
3789 static int
3790 mark_constant (rtx *current_rtx, void *data ATTRIBUTE_UNUSED)
3792 rtx x = *current_rtx;
3794 if (x == NULL_RTX || GET_CODE (x) != SYMBOL_REF)
3795 return 0;
3797 if (CONSTANT_POOL_ADDRESS_P (x))
3799 struct constant_descriptor_rtx *desc = SYMBOL_REF_CONSTANT (x);
3800 if (desc->mark == 0)
3802 desc->mark = 1;
3803 for_each_rtx (&desc->constant, mark_constant, NULL);
3806 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3808 tree exp = SYMBOL_REF_DECL (x);
3809 if (!TREE_ASM_WRITTEN (exp))
3811 n_deferred_constants--;
3812 output_constant_def_contents (x);
3816 return -1;
3819 /* Look through appropriate parts of INSN, marking all entries in the
3820 constant pool which are actually being used. Entries that are only
3821 referenced by other constants are also marked as used. Emit
3822 deferred strings that are used. */
3824 static void
3825 mark_constants (rtx insn)
3827 if (!INSN_P (insn))
3828 return;
3830 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3831 insns, not any notes that may be attached. We don't want to mark
3832 a constant just because it happens to appear in a REG_EQUIV note. */
3833 if (GET_CODE (PATTERN (insn)) == SEQUENCE)
3835 rtx seq = PATTERN (insn);
3836 int i, n = XVECLEN (seq, 0);
3837 for (i = 0; i < n; ++i)
3839 rtx subinsn = XVECEXP (seq, 0, i);
3840 if (INSN_P (subinsn))
3841 for_each_rtx (&PATTERN (subinsn), mark_constant, NULL);
3844 else
3845 for_each_rtx (&PATTERN (insn), mark_constant, NULL);
3848 /* Look through the instructions for this function, and mark all the
3849 entries in POOL which are actually being used. Emit deferred constants
3850 which have indeed been used. */
3852 static void
3853 mark_constant_pool (void)
3855 rtx insn, link;
3857 if (!crtl->uses_const_pool && n_deferred_constants == 0)
3858 return;
3860 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3861 mark_constants (insn);
3863 for (link = crtl->epilogue_delay_list;
3864 link;
3865 link = XEXP (link, 1))
3866 mark_constants (XEXP (link, 0));
3869 /* Write all the constants in POOL. */
3871 static void
3872 output_constant_pool_contents (struct rtx_constant_pool *pool)
3874 struct constant_descriptor_rtx *desc;
3876 for (desc = pool->first; desc ; desc = desc->next)
3877 if (desc->mark)
3879 /* If the constant is part of an object_block, make sure that
3880 the constant has been positioned within its block, but do not
3881 write out its definition yet. output_object_blocks will do
3882 that later. */
3883 if (SYMBOL_REF_HAS_BLOCK_INFO_P (desc->sym)
3884 && SYMBOL_REF_BLOCK (desc->sym))
3885 place_block_symbol (desc->sym);
3886 else
3888 switch_to_section (targetm.asm_out.select_rtx_section
3889 (desc->mode, desc->constant, desc->align));
3890 output_constant_pool_1 (desc, desc->align);
3895 /* Mark all constants that are used in the current function, then write
3896 out the function's private constant pool. */
3898 static void
3899 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
3900 tree fndecl ATTRIBUTE_UNUSED)
3902 struct rtx_constant_pool *pool = crtl->varasm.pool;
3904 /* It is possible for gcc to call force_const_mem and then to later
3905 discard the instructions which refer to the constant. In such a
3906 case we do not need to output the constant. */
3907 mark_constant_pool ();
3909 #ifdef ASM_OUTPUT_POOL_PROLOGUE
3910 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
3911 #endif
3913 output_constant_pool_contents (pool);
3915 #ifdef ASM_OUTPUT_POOL_EPILOGUE
3916 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
3917 #endif
3920 /* Write the contents of the shared constant pool. */
3922 void
3923 output_shared_constant_pool (void)
3925 output_constant_pool_contents (shared_constant_pool);
3928 /* Determine what kind of relocations EXP may need. */
3931 compute_reloc_for_constant (tree exp)
3933 int reloc = 0, reloc2;
3934 tree tem;
3936 switch (TREE_CODE (exp))
3938 case ADDR_EXPR:
3939 case FDESC_EXPR:
3940 /* Go inside any operations that get_inner_reference can handle and see
3941 if what's inside is a constant: no need to do anything here for
3942 addresses of variables or functions. */
3943 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
3944 tem = TREE_OPERAND (tem, 0))
3947 if (TREE_PUBLIC (tem))
3948 reloc |= 2;
3949 else
3950 reloc |= 1;
3951 break;
3953 case PLUS_EXPR:
3954 case POINTER_PLUS_EXPR:
3955 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3956 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
3957 break;
3959 case MINUS_EXPR:
3960 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3961 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
3962 /* The difference of two local labels is computable at link time. */
3963 if (reloc == 1 && reloc2 == 1)
3964 reloc = 0;
3965 else
3966 reloc |= reloc2;
3967 break;
3969 case NOP_EXPR:
3970 case CONVERT_EXPR:
3971 case VIEW_CONVERT_EXPR:
3972 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3973 break;
3975 case CONSTRUCTOR:
3977 unsigned HOST_WIDE_INT idx;
3978 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
3979 if (tem != 0)
3980 reloc |= compute_reloc_for_constant (tem);
3982 break;
3984 default:
3985 break;
3987 return reloc;
3990 /* Find all the constants whose addresses are referenced inside of EXP,
3991 and make sure assembler code with a label has been output for each one.
3992 Indicate whether an ADDR_EXPR has been encountered. */
3994 static void
3995 output_addressed_constants (tree exp)
3997 tree tem;
3999 switch (TREE_CODE (exp))
4001 case ADDR_EXPR:
4002 case FDESC_EXPR:
4003 /* Go inside any operations that get_inner_reference can handle and see
4004 if what's inside is a constant: no need to do anything here for
4005 addresses of variables or functions. */
4006 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
4007 tem = TREE_OPERAND (tem, 0))
4010 /* If we have an initialized CONST_DECL, retrieve the initializer. */
4011 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
4012 tem = DECL_INITIAL (tem);
4014 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
4015 output_constant_def (tem, 0);
4016 break;
4018 case PLUS_EXPR:
4019 case POINTER_PLUS_EXPR:
4020 case MINUS_EXPR:
4021 output_addressed_constants (TREE_OPERAND (exp, 1));
4022 /* Fall through. */
4024 case NOP_EXPR:
4025 case CONVERT_EXPR:
4026 case VIEW_CONVERT_EXPR:
4027 output_addressed_constants (TREE_OPERAND (exp, 0));
4028 break;
4030 case CONSTRUCTOR:
4032 unsigned HOST_WIDE_INT idx;
4033 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (exp), idx, tem)
4034 if (tem != 0)
4035 output_addressed_constants (tem);
4037 break;
4039 default:
4040 break;
4044 /* Whether a constructor CTOR is a valid static constant initializer if all
4045 its elements are. This used to be internal to initializer_constant_valid_p
4046 and has been exposed to let other functions like categorize_ctor_elements
4047 evaluate the property while walking a constructor for other purposes. */
4049 bool
4050 constructor_static_from_elts_p (const_tree ctor)
4052 return (TREE_CONSTANT (ctor)
4053 && (TREE_CODE (TREE_TYPE (ctor)) == UNION_TYPE
4054 || TREE_CODE (TREE_TYPE (ctor)) == RECORD_TYPE)
4055 && !VEC_empty (constructor_elt, CONSTRUCTOR_ELTS (ctor)));
4058 /* Return nonzero if VALUE is a valid constant-valued expression
4059 for use in initializing a static variable; one that can be an
4060 element of a "constant" initializer.
4062 Return null_pointer_node if the value is absolute;
4063 if it is relocatable, return the variable that determines the relocation.
4064 We assume that VALUE has been folded as much as possible;
4065 therefore, we do not need to check for such things as
4066 arithmetic-combinations of integers. */
4068 tree
4069 initializer_constant_valid_p (tree value, tree endtype)
4071 switch (TREE_CODE (value))
4073 case CONSTRUCTOR:
4074 if (constructor_static_from_elts_p (value))
4076 unsigned HOST_WIDE_INT idx;
4077 tree elt;
4078 bool absolute = true;
4080 FOR_EACH_CONSTRUCTOR_VALUE (CONSTRUCTOR_ELTS (value), idx, elt)
4082 tree reloc;
4083 reloc = initializer_constant_valid_p (elt, TREE_TYPE (elt));
4084 if (!reloc)
4085 return NULL_TREE;
4086 if (reloc != null_pointer_node)
4087 absolute = false;
4089 /* For a non-absolute relocation, there is no single
4090 variable that can be "the variable that determines the
4091 relocation." */
4092 return absolute ? null_pointer_node : error_mark_node;
4095 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
4097 case INTEGER_CST:
4098 case VECTOR_CST:
4099 case REAL_CST:
4100 case FIXED_CST:
4101 case STRING_CST:
4102 case COMPLEX_CST:
4103 return null_pointer_node;
4105 case ADDR_EXPR:
4106 case FDESC_EXPR:
4107 value = staticp (TREE_OPERAND (value, 0));
4108 if (value)
4110 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out to
4111 be a constant, this is old-skool offsetof-like nonsense. */
4112 if (TREE_CODE (value) == INDIRECT_REF
4113 && TREE_CONSTANT (TREE_OPERAND (value, 0)))
4114 return null_pointer_node;
4115 /* Taking the address of a nested function involves a trampoline. */
4116 if (TREE_CODE (value) == FUNCTION_DECL
4117 && decl_function_context (value)
4118 && !DECL_NO_STATIC_CHAIN (value))
4119 return NULL_TREE;
4120 /* "&{...}" requires a temporary to hold the constructed
4121 object. */
4122 if (TREE_CODE (value) == CONSTRUCTOR)
4123 return NULL_TREE;
4125 return value;
4127 case VIEW_CONVERT_EXPR:
4128 case NON_LVALUE_EXPR:
4129 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
4131 case CONVERT_EXPR:
4132 case NOP_EXPR:
4134 tree src;
4135 tree src_type;
4136 tree dest_type;
4138 src = TREE_OPERAND (value, 0);
4139 src_type = TREE_TYPE (src);
4140 dest_type = TREE_TYPE (value);
4142 /* Allow conversions between pointer types, floating-point
4143 types, and offset types. */
4144 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
4145 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
4146 || (TREE_CODE (dest_type) == OFFSET_TYPE
4147 && TREE_CODE (src_type) == OFFSET_TYPE))
4148 return initializer_constant_valid_p (src, endtype);
4150 /* Allow length-preserving conversions between integer types. */
4151 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
4152 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
4153 return initializer_constant_valid_p (src, endtype);
4155 /* Allow conversions between other integer types only if
4156 explicit value. */
4157 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type))
4159 tree inner = initializer_constant_valid_p (src, endtype);
4160 if (inner == null_pointer_node)
4161 return null_pointer_node;
4162 break;
4165 /* Allow (int) &foo provided int is as wide as a pointer. */
4166 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
4167 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
4168 return initializer_constant_valid_p (src, endtype);
4170 /* Likewise conversions from int to pointers, but also allow
4171 conversions from 0. */
4172 if ((POINTER_TYPE_P (dest_type)
4173 || TREE_CODE (dest_type) == OFFSET_TYPE)
4174 && INTEGRAL_TYPE_P (src_type))
4176 if (TREE_CODE (src) == INTEGER_CST
4177 && TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type))
4178 return null_pointer_node;
4179 if (integer_zerop (src))
4180 return null_pointer_node;
4181 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
4182 return initializer_constant_valid_p (src, endtype);
4185 /* Allow conversions to struct or union types if the value
4186 inside is okay. */
4187 if (TREE_CODE (dest_type) == RECORD_TYPE
4188 || TREE_CODE (dest_type) == UNION_TYPE)
4189 return initializer_constant_valid_p (src, endtype);
4191 break;
4193 case POINTER_PLUS_EXPR:
4194 case PLUS_EXPR:
4195 if (! INTEGRAL_TYPE_P (endtype)
4196 || TYPE_PRECISION (endtype) >= POINTER_SIZE)
4198 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0),
4199 endtype);
4200 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1),
4201 endtype);
4202 /* If either term is absolute, use the other term's relocation. */
4203 if (valid0 == null_pointer_node)
4204 return valid1;
4205 if (valid1 == null_pointer_node)
4206 return valid0;
4208 break;
4210 case MINUS_EXPR:
4211 if (! INTEGRAL_TYPE_P (endtype)
4212 || TYPE_PRECISION (endtype) >= POINTER_SIZE)
4214 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0),
4215 endtype);
4216 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1),
4217 endtype);
4218 /* Win if second argument is absolute. */
4219 if (valid1 == null_pointer_node)
4220 return valid0;
4221 /* Win if both arguments have the same relocation.
4222 Then the value is absolute. */
4223 if (valid0 == valid1 && valid0 != 0)
4224 return null_pointer_node;
4226 /* Since GCC guarantees that string constants are unique in the
4227 generated code, a subtraction between two copies of the same
4228 constant string is absolute. */
4229 if (valid0 && TREE_CODE (valid0) == STRING_CST
4230 && valid1 && TREE_CODE (valid1) == STRING_CST
4231 && operand_equal_p (valid0, valid1, 1))
4232 return null_pointer_node;
4235 /* Support narrowing differences. */
4236 if (INTEGRAL_TYPE_P (endtype))
4238 tree op0, op1;
4240 op0 = TREE_OPERAND (value, 0);
4241 op1 = TREE_OPERAND (value, 1);
4243 /* Like STRIP_NOPS except allow the operand mode to widen.
4244 This works around a feature of fold that simplifies
4245 (int)(p1 - p2) to ((int)p1 - (int)p2) under the theory
4246 that the narrower operation is cheaper. */
4248 while (TREE_CODE (op0) == NOP_EXPR
4249 || TREE_CODE (op0) == CONVERT_EXPR
4250 || TREE_CODE (op0) == NON_LVALUE_EXPR)
4252 tree inner = TREE_OPERAND (op0, 0);
4253 if (inner == error_mark_node
4254 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4255 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
4256 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4257 break;
4258 op0 = inner;
4261 while (TREE_CODE (op1) == NOP_EXPR
4262 || TREE_CODE (op1) == CONVERT_EXPR
4263 || TREE_CODE (op1) == NON_LVALUE_EXPR)
4265 tree inner = TREE_OPERAND (op1, 0);
4266 if (inner == error_mark_node
4267 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
4268 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
4269 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
4270 break;
4271 op1 = inner;
4274 op0 = initializer_constant_valid_p (op0, endtype);
4275 op1 = initializer_constant_valid_p (op1, endtype);
4277 /* Both initializers must be known. */
4278 if (op0 && op1)
4280 if (op0 == op1)
4281 return null_pointer_node;
4283 /* Support differences between labels. */
4284 if (TREE_CODE (op0) == LABEL_DECL
4285 && TREE_CODE (op1) == LABEL_DECL)
4286 return null_pointer_node;
4288 if (TREE_CODE (op0) == STRING_CST
4289 && TREE_CODE (op1) == STRING_CST
4290 && operand_equal_p (op0, op1, 1))
4291 return null_pointer_node;
4294 break;
4296 default:
4297 break;
4300 return 0;
4303 /* Output assembler code for constant EXP to FILE, with no label.
4304 This includes the pseudo-op such as ".int" or ".byte", and a newline.
4305 Assumes output_addressed_constants has been done on EXP already.
4307 Generate exactly SIZE bytes of assembler data, padding at the end
4308 with zeros if necessary. SIZE must always be specified.
4310 SIZE is important for structure constructors,
4311 since trailing members may have been omitted from the constructor.
4312 It is also important for initialization of arrays from string constants
4313 since the full length of the string constant might not be wanted.
4314 It is also needed for initialization of unions, where the initializer's
4315 type is just one member, and that may not be as long as the union.
4317 There a case in which we would fail to output exactly SIZE bytes:
4318 for a structure constructor that wants to produce more than SIZE bytes.
4319 But such constructors will never be generated for any possible input.
4321 ALIGN is the alignment of the data in bits. */
4323 void
4324 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align)
4326 enum tree_code code;
4327 unsigned HOST_WIDE_INT thissize;
4329 if (size == 0 || flag_syntax_only)
4330 return;
4332 /* See if we're trying to initialize a pointer in a non-default mode
4333 to the address of some declaration somewhere. If the target says
4334 the mode is valid for pointers, assume the target has a way of
4335 resolving it. */
4336 if (TREE_CODE (exp) == NOP_EXPR
4337 && POINTER_TYPE_P (TREE_TYPE (exp))
4338 && targetm.valid_pointer_mode (TYPE_MODE (TREE_TYPE (exp))))
4340 tree saved_type = TREE_TYPE (exp);
4342 /* Peel off any intermediate conversions-to-pointer for valid
4343 pointer modes. */
4344 while (TREE_CODE (exp) == NOP_EXPR
4345 && POINTER_TYPE_P (TREE_TYPE (exp))
4346 && targetm.valid_pointer_mode (TYPE_MODE (TREE_TYPE (exp))))
4347 exp = TREE_OPERAND (exp, 0);
4349 /* If what we're left with is the address of something, we can
4350 convert the address to the final type and output it that
4351 way. */
4352 if (TREE_CODE (exp) == ADDR_EXPR)
4353 exp = build1 (ADDR_EXPR, saved_type, TREE_OPERAND (exp, 0));
4354 /* Likewise for constant ints. */
4355 else if (TREE_CODE (exp) == INTEGER_CST)
4356 exp = build_int_cst_wide (saved_type, TREE_INT_CST_LOW (exp),
4357 TREE_INT_CST_HIGH (exp));
4361 /* Eliminate any conversions since we'll be outputting the underlying
4362 constant. */
4363 while (TREE_CODE (exp) == NOP_EXPR || TREE_CODE (exp) == CONVERT_EXPR
4364 || TREE_CODE (exp) == NON_LVALUE_EXPR
4365 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
4367 HOST_WIDE_INT type_size = int_size_in_bytes (TREE_TYPE (exp));
4368 HOST_WIDE_INT op_size = int_size_in_bytes (TREE_TYPE (TREE_OPERAND (exp, 0)));
4370 /* Make sure eliminating the conversion is really a no-op, except with
4371 VIEW_CONVERT_EXPRs to allow for wild Ada unchecked conversions and
4372 union types to allow for Ada unchecked unions. */
4373 if (type_size > op_size
4374 && TREE_CODE (exp) != VIEW_CONVERT_EXPR
4375 && TREE_CODE (TREE_TYPE (exp)) != UNION_TYPE)
4376 /* Keep the conversion. */
4377 break;
4378 else
4379 exp = TREE_OPERAND (exp, 0);
4382 code = TREE_CODE (TREE_TYPE (exp));
4383 thissize = int_size_in_bytes (TREE_TYPE (exp));
4385 /* Allow a constructor with no elements for any data type.
4386 This means to fill the space with zeros. */
4387 if (TREE_CODE (exp) == CONSTRUCTOR
4388 && VEC_empty (constructor_elt, CONSTRUCTOR_ELTS (exp)))
4390 assemble_zeros (size);
4391 return;
4394 if (TREE_CODE (exp) == FDESC_EXPR)
4396 #ifdef ASM_OUTPUT_FDESC
4397 HOST_WIDE_INT part = tree_low_cst (TREE_OPERAND (exp, 1), 0);
4398 tree decl = TREE_OPERAND (exp, 0);
4399 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
4400 #else
4401 gcc_unreachable ();
4402 #endif
4403 return;
4406 /* Now output the underlying data. If we've handling the padding, return.
4407 Otherwise, break and ensure SIZE is the size written. */
4408 switch (code)
4410 case BOOLEAN_TYPE:
4411 case INTEGER_TYPE:
4412 case ENUMERAL_TYPE:
4413 case POINTER_TYPE:
4414 case REFERENCE_TYPE:
4415 case OFFSET_TYPE:
4416 case FIXED_POINT_TYPE:
4417 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
4418 EXPAND_INITIALIZER),
4419 MIN (size, thissize), align, 0))
4420 error ("initializer for integer/fixed-point value is too complicated");
4421 break;
4423 case REAL_TYPE:
4424 if (TREE_CODE (exp) != REAL_CST)
4425 error ("initializer for floating value is not a floating constant");
4427 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)), align);
4428 break;
4430 case COMPLEX_TYPE:
4431 output_constant (TREE_REALPART (exp), thissize / 2, align);
4432 output_constant (TREE_IMAGPART (exp), thissize / 2,
4433 min_align (align, BITS_PER_UNIT * (thissize / 2)));
4434 break;
4436 case ARRAY_TYPE:
4437 case VECTOR_TYPE:
4438 switch (TREE_CODE (exp))
4440 case CONSTRUCTOR:
4441 output_constructor (exp, size, align);
4442 return;
4443 case STRING_CST:
4444 thissize = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp),
4445 size);
4446 assemble_string (TREE_STRING_POINTER (exp), thissize);
4447 break;
4449 case VECTOR_CST:
4451 int elt_size;
4452 tree link;
4453 unsigned int nalign;
4454 enum machine_mode inner;
4456 inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
4457 nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
4459 elt_size = GET_MODE_SIZE (inner);
4461 link = TREE_VECTOR_CST_ELTS (exp);
4462 output_constant (TREE_VALUE (link), elt_size, align);
4463 thissize = elt_size;
4464 while ((link = TREE_CHAIN (link)) != NULL)
4466 output_constant (TREE_VALUE (link), elt_size, nalign);
4467 thissize += elt_size;
4469 break;
4471 default:
4472 gcc_unreachable ();
4474 break;
4476 case RECORD_TYPE:
4477 case UNION_TYPE:
4478 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
4479 output_constructor (exp, size, align);
4480 return;
4482 case ERROR_MARK:
4483 return;
4485 default:
4486 gcc_unreachable ();
4489 if (size > thissize)
4490 assemble_zeros (size - thissize);
4494 /* Subroutine of output_constructor, used for computing the size of
4495 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4496 type with an unspecified upper bound. */
4498 static unsigned HOST_WIDE_INT
4499 array_size_for_constructor (tree val)
4501 tree max_index, i;
4502 unsigned HOST_WIDE_INT cnt;
4503 tree index, value, tmp;
4505 /* This code used to attempt to handle string constants that are not
4506 arrays of single-bytes, but nothing else does, so there's no point in
4507 doing it here. */
4508 if (TREE_CODE (val) == STRING_CST)
4509 return TREE_STRING_LENGTH (val);
4511 max_index = NULL_TREE;
4512 FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (val), cnt, index, value)
4514 if (TREE_CODE (index) == RANGE_EXPR)
4515 index = TREE_OPERAND (index, 1);
4516 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
4517 max_index = index;
4520 if (max_index == NULL_TREE)
4521 return 0;
4523 /* Compute the total number of array elements. */
4524 tmp = TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)));
4525 i = size_binop (MINUS_EXPR, fold_convert (sizetype, max_index),
4526 fold_convert (sizetype, tmp));
4527 i = size_binop (PLUS_EXPR, i, build_int_cst (sizetype, 1));
4529 /* Multiply by the array element unit size to find number of bytes. */
4530 i = size_binop (MULT_EXPR, i, TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
4532 return tree_low_cst (i, 1);
4535 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
4536 Generate at least SIZE bytes, padding if necessary. */
4538 static void
4539 output_constructor (tree exp, unsigned HOST_WIDE_INT size,
4540 unsigned int align)
4542 tree type = TREE_TYPE (exp);
4543 tree field = 0;
4544 tree min_index = 0;
4545 /* Number of bytes output or skipped so far.
4546 In other words, current position within the constructor. */
4547 HOST_WIDE_INT total_bytes = 0;
4548 /* Nonzero means BYTE contains part of a byte, to be output. */
4549 int byte_buffer_in_use = 0;
4550 int byte = 0;
4551 unsigned HOST_WIDE_INT cnt;
4552 constructor_elt *ce;
4554 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
4556 if (TREE_CODE (type) == RECORD_TYPE)
4557 field = TYPE_FIELDS (type);
4559 if (TREE_CODE (type) == ARRAY_TYPE
4560 && TYPE_DOMAIN (type) != 0)
4561 min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (type));
4563 /* As LINK goes through the elements of the constant,
4564 FIELD goes through the structure fields, if the constant is a structure.
4565 if the constant is a union, then we override this,
4566 by getting the field from the TREE_LIST element.
4567 But the constant could also be an array. Then FIELD is zero.
4569 There is always a maximum of one element in the chain LINK for unions
4570 (even if the initializer in a source program incorrectly contains
4571 more one). */
4572 for (cnt = 0;
4573 VEC_iterate (constructor_elt, CONSTRUCTOR_ELTS (exp), cnt, ce);
4574 cnt++, field = field ? TREE_CHAIN (field) : 0)
4576 tree val = ce->value;
4577 tree index = 0;
4579 /* The element in a union constructor specifies the proper field
4580 or index. */
4581 if ((TREE_CODE (type) == RECORD_TYPE || TREE_CODE (type) == UNION_TYPE
4582 || TREE_CODE (type) == QUAL_UNION_TYPE)
4583 && ce->index != 0)
4584 field = ce->index;
4586 else if (TREE_CODE (type) == ARRAY_TYPE)
4587 index = ce->index;
4589 #ifdef ASM_COMMENT_START
4590 if (field && flag_verbose_asm)
4591 fprintf (asm_out_file, "%s %s:\n",
4592 ASM_COMMENT_START,
4593 DECL_NAME (field)
4594 ? IDENTIFIER_POINTER (DECL_NAME (field))
4595 : "<anonymous>");
4596 #endif
4598 /* Eliminate the marker that makes a cast not be an lvalue. */
4599 if (val != 0)
4600 STRIP_NOPS (val);
4602 if (index && TREE_CODE (index) == RANGE_EXPR)
4604 unsigned HOST_WIDE_INT fieldsize
4605 = int_size_in_bytes (TREE_TYPE (type));
4606 HOST_WIDE_INT lo_index = tree_low_cst (TREE_OPERAND (index, 0), 0);
4607 HOST_WIDE_INT hi_index = tree_low_cst (TREE_OPERAND (index, 1), 0);
4608 HOST_WIDE_INT index;
4609 unsigned int align2 = min_align (align, fieldsize * BITS_PER_UNIT);
4611 for (index = lo_index; index <= hi_index; index++)
4613 /* Output the element's initial value. */
4614 if (val == 0)
4615 assemble_zeros (fieldsize);
4616 else
4617 output_constant (val, fieldsize, align2);
4619 /* Count its size. */
4620 total_bytes += fieldsize;
4623 else if (field == 0 || !DECL_BIT_FIELD (field))
4625 /* An element that is not a bit-field. */
4627 unsigned HOST_WIDE_INT fieldsize;
4628 /* Since this structure is static,
4629 we know the positions are constant. */
4630 HOST_WIDE_INT pos = field ? int_byte_position (field) : 0;
4631 unsigned int align2;
4633 if (index != 0)
4634 pos = (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (val)), 1)
4635 * (tree_low_cst (index, 0) - tree_low_cst (min_index, 0)));
4637 /* Output any buffered-up bit-fields preceding this element. */
4638 if (byte_buffer_in_use)
4640 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4641 total_bytes++;
4642 byte_buffer_in_use = 0;
4645 /* Advance to offset of this element.
4646 Note no alignment needed in an array, since that is guaranteed
4647 if each element has the proper size. */
4648 if ((field != 0 || index != 0) && pos != total_bytes)
4650 gcc_assert (pos >= total_bytes);
4651 assemble_zeros (pos - total_bytes);
4652 total_bytes = pos;
4655 /* Find the alignment of this element. */
4656 align2 = min_align (align, BITS_PER_UNIT * pos);
4658 /* Determine size this element should occupy. */
4659 if (field)
4661 fieldsize = 0;
4663 /* If this is an array with an unspecified upper bound,
4664 the initializer determines the size. */
4665 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
4666 but we cannot do this until the deprecated support for
4667 initializing zero-length array members is removed. */
4668 if (TREE_CODE (TREE_TYPE (field)) == ARRAY_TYPE
4669 && TYPE_DOMAIN (TREE_TYPE (field))
4670 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (field))))
4672 fieldsize = array_size_for_constructor (val);
4673 /* Given a non-empty initialization, this field had
4674 better be last. */
4675 gcc_assert (!fieldsize || !TREE_CHAIN (field));
4677 else if (DECL_SIZE_UNIT (field))
4679 /* ??? This can't be right. If the decl size overflows
4680 a host integer we will silently emit no data. */
4681 if (host_integerp (DECL_SIZE_UNIT (field), 1))
4682 fieldsize = tree_low_cst (DECL_SIZE_UNIT (field), 1);
4685 else
4686 fieldsize = int_size_in_bytes (TREE_TYPE (type));
4688 /* Output the element's initial value. */
4689 if (val == 0)
4690 assemble_zeros (fieldsize);
4691 else
4692 output_constant (val, fieldsize, align2);
4694 /* Count its size. */
4695 total_bytes += fieldsize;
4697 else if (val != 0 && TREE_CODE (val) != INTEGER_CST)
4698 error ("invalid initial value for member %qs",
4699 IDENTIFIER_POINTER (DECL_NAME (field)));
4700 else
4702 /* Element that is a bit-field. */
4704 HOST_WIDE_INT next_offset = int_bit_position (field);
4705 HOST_WIDE_INT end_offset
4706 = (next_offset + tree_low_cst (DECL_SIZE (field), 1));
4708 if (val == 0)
4709 val = integer_zero_node;
4711 /* If this field does not start in this (or, next) byte,
4712 skip some bytes. */
4713 if (next_offset / BITS_PER_UNIT != total_bytes)
4715 /* Output remnant of any bit field in previous bytes. */
4716 if (byte_buffer_in_use)
4718 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4719 total_bytes++;
4720 byte_buffer_in_use = 0;
4723 /* If still not at proper byte, advance to there. */
4724 if (next_offset / BITS_PER_UNIT != total_bytes)
4726 gcc_assert (next_offset / BITS_PER_UNIT >= total_bytes);
4727 assemble_zeros (next_offset / BITS_PER_UNIT - total_bytes);
4728 total_bytes = next_offset / BITS_PER_UNIT;
4732 if (! byte_buffer_in_use)
4733 byte = 0;
4735 /* We must split the element into pieces that fall within
4736 separate bytes, and combine each byte with previous or
4737 following bit-fields. */
4739 /* next_offset is the offset n fbits from the beginning of
4740 the structure to the next bit of this element to be processed.
4741 end_offset is the offset of the first bit past the end of
4742 this element. */
4743 while (next_offset < end_offset)
4745 int this_time;
4746 int shift;
4747 HOST_WIDE_INT value;
4748 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
4749 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
4751 /* Advance from byte to byte
4752 within this element when necessary. */
4753 while (next_byte != total_bytes)
4755 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4756 total_bytes++;
4757 byte = 0;
4760 /* Number of bits we can process at once
4761 (all part of the same byte). */
4762 this_time = MIN (end_offset - next_offset,
4763 BITS_PER_UNIT - next_bit);
4764 if (BYTES_BIG_ENDIAN)
4766 /* On big-endian machine, take the most significant bits
4767 first (of the bits that are significant)
4768 and put them into bytes from the most significant end. */
4769 shift = end_offset - next_offset - this_time;
4771 /* Don't try to take a bunch of bits that cross
4772 the word boundary in the INTEGER_CST. We can
4773 only select bits from the LOW or HIGH part
4774 not from both. */
4775 if (shift < HOST_BITS_PER_WIDE_INT
4776 && shift + this_time > HOST_BITS_PER_WIDE_INT)
4778 this_time = shift + this_time - HOST_BITS_PER_WIDE_INT;
4779 shift = HOST_BITS_PER_WIDE_INT;
4782 /* Now get the bits from the appropriate constant word. */
4783 if (shift < HOST_BITS_PER_WIDE_INT)
4784 value = TREE_INT_CST_LOW (val);
4785 else
4787 gcc_assert (shift < 2 * HOST_BITS_PER_WIDE_INT);
4788 value = TREE_INT_CST_HIGH (val);
4789 shift -= HOST_BITS_PER_WIDE_INT;
4792 /* Get the result. This works only when:
4793 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
4794 byte |= (((value >> shift)
4795 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
4796 << (BITS_PER_UNIT - this_time - next_bit));
4798 else
4800 /* On little-endian machines,
4801 take first the least significant bits of the value
4802 and pack them starting at the least significant
4803 bits of the bytes. */
4804 shift = next_offset - int_bit_position (field);
4806 /* Don't try to take a bunch of bits that cross
4807 the word boundary in the INTEGER_CST. We can
4808 only select bits from the LOW or HIGH part
4809 not from both. */
4810 if (shift < HOST_BITS_PER_WIDE_INT
4811 && shift + this_time > HOST_BITS_PER_WIDE_INT)
4812 this_time = (HOST_BITS_PER_WIDE_INT - shift);
4814 /* Now get the bits from the appropriate constant word. */
4815 if (shift < HOST_BITS_PER_WIDE_INT)
4816 value = TREE_INT_CST_LOW (val);
4817 else
4819 gcc_assert (shift < 2 * HOST_BITS_PER_WIDE_INT);
4820 value = TREE_INT_CST_HIGH (val);
4821 shift -= HOST_BITS_PER_WIDE_INT;
4824 /* Get the result. This works only when:
4825 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
4826 byte |= (((value >> shift)
4827 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
4828 << next_bit);
4831 next_offset += this_time;
4832 byte_buffer_in_use = 1;
4837 if (byte_buffer_in_use)
4839 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4840 total_bytes++;
4843 if ((unsigned HOST_WIDE_INT)total_bytes < size)
4844 assemble_zeros (size - total_bytes);
4847 /* This TREE_LIST contains any weak symbol declarations waiting
4848 to be emitted. */
4849 static GTY(()) tree weak_decls;
4851 /* Mark DECL as weak. */
4853 static void
4854 mark_weak (tree decl)
4856 DECL_WEAK (decl) = 1;
4858 if (DECL_RTL_SET_P (decl)
4859 && MEM_P (DECL_RTL (decl))
4860 && XEXP (DECL_RTL (decl), 0)
4861 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
4862 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
4865 /* Merge weak status between NEWDECL and OLDDECL. */
4867 void
4868 merge_weak (tree newdecl, tree olddecl)
4870 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
4872 if (DECL_WEAK (newdecl) && SUPPORTS_WEAK)
4874 tree *pwd;
4875 /* We put the NEWDECL on the weak_decls list at some point
4876 and OLDDECL as well. Keep just OLDDECL on the list. */
4877 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
4878 if (TREE_VALUE (*pwd) == newdecl)
4880 *pwd = TREE_CHAIN (*pwd);
4881 break;
4884 return;
4887 if (DECL_WEAK (newdecl))
4889 tree wd;
4891 /* NEWDECL is weak, but OLDDECL is not. */
4893 /* If we already output the OLDDECL, we're in trouble; we can't
4894 go back and make it weak. This error cannot be caught in
4895 declare_weak because the NEWDECL and OLDDECL was not yet
4896 been merged; therefore, TREE_ASM_WRITTEN was not set. */
4897 if (TREE_ASM_WRITTEN (olddecl))
4898 error ("weak declaration of %q+D must precede definition",
4899 newdecl);
4901 /* If we've already generated rtl referencing OLDDECL, we may
4902 have done so in a way that will not function properly with
4903 a weak symbol. */
4904 else if (TREE_USED (olddecl)
4905 && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)))
4906 warning (0, "weak declaration of %q+D after first use results "
4907 "in unspecified behavior", newdecl);
4909 if (SUPPORTS_WEAK)
4911 /* We put the NEWDECL on the weak_decls list at some point.
4912 Replace it with the OLDDECL. */
4913 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
4914 if (TREE_VALUE (wd) == newdecl)
4916 TREE_VALUE (wd) = olddecl;
4917 break;
4919 /* We may not find the entry on the list. If NEWDECL is a
4920 weak alias, then we will have already called
4921 globalize_decl to remove the entry; in that case, we do
4922 not need to do anything. */
4925 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
4926 mark_weak (olddecl);
4928 else
4929 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
4930 weak. Just update NEWDECL to indicate that it's weak too. */
4931 mark_weak (newdecl);
4934 /* Declare DECL to be a weak symbol. */
4936 void
4937 declare_weak (tree decl)
4939 if (! TREE_PUBLIC (decl))
4940 error ("weak declaration of %q+D must be public", decl);
4941 else if (TREE_CODE (decl) == FUNCTION_DECL && TREE_ASM_WRITTEN (decl))
4942 error ("weak declaration of %q+D must precede definition", decl);
4943 else if (SUPPORTS_WEAK)
4945 if (! DECL_WEAK (decl))
4946 weak_decls = tree_cons (NULL, decl, weak_decls);
4948 else
4949 warning (0, "weak declaration of %q+D not supported", decl);
4951 mark_weak (decl);
4954 static void
4955 weak_finish_1 (tree decl)
4957 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
4958 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
4959 #endif
4961 if (! TREE_USED (decl))
4962 return;
4964 #ifdef ASM_WEAKEN_DECL
4965 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
4966 #else
4967 #ifdef ASM_WEAKEN_LABEL
4968 ASM_WEAKEN_LABEL (asm_out_file, name);
4969 #else
4970 #ifdef ASM_OUTPUT_WEAK_ALIAS
4972 static bool warn_once = 0;
4973 if (! warn_once)
4975 warning (0, "only weak aliases are supported in this configuration");
4976 warn_once = 1;
4978 return;
4980 #endif
4981 #endif
4982 #endif
4985 /* This TREE_LIST contains weakref targets. */
4987 static GTY(()) tree weakref_targets;
4989 /* Forward declaration. */
4990 static tree find_decl_and_mark_needed (tree decl, tree target);
4992 /* Emit any pending weak declarations. */
4994 void
4995 weak_finish (void)
4997 tree t;
4999 for (t = weakref_targets; t; t = TREE_CHAIN (t))
5001 tree alias_decl = TREE_PURPOSE (t);
5002 tree target = ultimate_transparent_alias_target (&TREE_VALUE (t));
5004 if (! TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (alias_decl)))
5005 /* Remove alias_decl from the weak list, but leave entries for
5006 the target alone. */
5007 target = NULL_TREE;
5008 #ifndef ASM_OUTPUT_WEAKREF
5009 else if (! TREE_SYMBOL_REFERENCED (target))
5011 /* Use ASM_WEAKEN_LABEL only if ASM_WEAKEN_DECL is not
5012 defined, otherwise we and weak_finish_1 would use
5013 different macros. */
5014 # if defined ASM_WEAKEN_LABEL && ! defined ASM_WEAKEN_DECL
5015 ASM_WEAKEN_LABEL (asm_out_file, IDENTIFIER_POINTER (target));
5016 # else
5017 tree decl = find_decl_and_mark_needed (alias_decl, target);
5019 if (! decl)
5021 decl = build_decl (TREE_CODE (alias_decl), target,
5022 TREE_TYPE (alias_decl));
5024 DECL_EXTERNAL (decl) = 1;
5025 TREE_PUBLIC (decl) = 1;
5026 DECL_ARTIFICIAL (decl) = 1;
5027 TREE_NOTHROW (decl) = TREE_NOTHROW (alias_decl);
5028 TREE_USED (decl) = 1;
5031 weak_finish_1 (decl);
5032 # endif
5034 #endif
5037 tree *p;
5038 tree t2;
5040 /* Remove the alias and the target from the pending weak list
5041 so that we do not emit any .weak directives for the former,
5042 nor multiple .weak directives for the latter. */
5043 for (p = &weak_decls; (t2 = *p) ; )
5045 if (TREE_VALUE (t2) == alias_decl
5046 || target == DECL_ASSEMBLER_NAME (TREE_VALUE (t2)))
5047 *p = TREE_CHAIN (t2);
5048 else
5049 p = &TREE_CHAIN (t2);
5052 /* Remove other weakrefs to the same target, to speed things up. */
5053 for (p = &TREE_CHAIN (t); (t2 = *p) ; )
5055 if (target == ultimate_transparent_alias_target (&TREE_VALUE (t2)))
5056 *p = TREE_CHAIN (t2);
5057 else
5058 p = &TREE_CHAIN (t2);
5063 for (t = weak_decls; t; t = TREE_CHAIN (t))
5065 tree decl = TREE_VALUE (t);
5067 weak_finish_1 (decl);
5071 /* Emit the assembly bits to indicate that DECL is globally visible. */
5073 static void
5074 globalize_decl (tree decl)
5077 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
5078 if (DECL_WEAK (decl))
5080 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
5081 tree *p, t;
5083 #ifdef ASM_WEAKEN_DECL
5084 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
5085 #else
5086 ASM_WEAKEN_LABEL (asm_out_file, name);
5087 #endif
5089 /* Remove this function from the pending weak list so that
5090 we do not emit multiple .weak directives for it. */
5091 for (p = &weak_decls; (t = *p) ; )
5093 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5094 *p = TREE_CHAIN (t);
5095 else
5096 p = &TREE_CHAIN (t);
5099 /* Remove weakrefs to the same target from the pending weakref
5100 list, for the same reason. */
5101 for (p = &weakref_targets; (t = *p) ; )
5103 if (DECL_ASSEMBLER_NAME (decl)
5104 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5105 *p = TREE_CHAIN (t);
5106 else
5107 p = &TREE_CHAIN (t);
5110 return;
5112 #endif
5114 targetm.asm_out.globalize_decl_name (asm_out_file, decl);
5117 /* We have to be able to tell cgraph about the needed-ness of the target
5118 of an alias. This requires that the decl have been defined. Aliases
5119 that precede their definition have to be queued for later processing. */
5121 typedef struct alias_pair GTY(())
5123 tree decl;
5124 tree target;
5125 } alias_pair;
5127 /* Define gc'd vector type. */
5128 DEF_VEC_O(alias_pair);
5129 DEF_VEC_ALLOC_O(alias_pair,gc);
5131 static GTY(()) VEC(alias_pair,gc) *alias_pairs;
5133 /* Given an assembly name, find the decl it is associated with. At the
5134 same time, mark it needed for cgraph. */
5136 static tree
5137 find_decl_and_mark_needed (tree decl, tree target)
5139 struct cgraph_node *fnode = NULL;
5140 struct varpool_node *vnode = NULL;
5142 if (TREE_CODE (decl) == FUNCTION_DECL)
5144 fnode = cgraph_node_for_asm (target);
5145 if (fnode == NULL)
5146 vnode = varpool_node_for_asm (target);
5148 else
5150 vnode = varpool_node_for_asm (target);
5151 if (vnode == NULL)
5152 fnode = cgraph_node_for_asm (target);
5155 if (fnode)
5157 /* We can't mark function nodes as used after cgraph global info
5158 is finished. This wouldn't generally be necessary, but C++
5159 virtual table thunks are introduced late in the game and
5160 might seem like they need marking, although in fact they
5161 don't. */
5162 if (! cgraph_global_info_ready)
5163 cgraph_mark_needed_node (fnode);
5164 return fnode->decl;
5166 else if (vnode)
5168 varpool_mark_needed_node (vnode);
5169 return vnode->decl;
5171 else
5172 return NULL_TREE;
5175 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
5176 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
5177 tree node is DECL to have the value of the tree node TARGET. */
5179 static void
5180 do_assemble_alias (tree decl, tree target)
5182 if (TREE_ASM_WRITTEN (decl))
5183 return;
5185 TREE_ASM_WRITTEN (decl) = 1;
5186 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
5188 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5190 ultimate_transparent_alias_target (&target);
5192 if (!targetm.have_tls
5193 && TREE_CODE (decl) == VAR_DECL
5194 && DECL_THREAD_LOCAL_P (decl))
5196 decl = emutls_decl (decl);
5197 target = get_emutls_object_name (target);
5200 if (!TREE_SYMBOL_REFERENCED (target))
5201 weakref_targets = tree_cons (decl, target, weakref_targets);
5203 #ifdef ASM_OUTPUT_WEAKREF
5204 ASM_OUTPUT_WEAKREF (asm_out_file, decl,
5205 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5206 IDENTIFIER_POINTER (target));
5207 #else
5208 if (!SUPPORTS_WEAK)
5210 error ("%Jweakref is not supported in this configuration", decl);
5211 return;
5213 #endif
5214 return;
5217 if (!targetm.have_tls
5218 && TREE_CODE (decl) == VAR_DECL
5219 && DECL_THREAD_LOCAL_P (decl))
5221 decl = emutls_decl (decl);
5222 target = get_emutls_object_name (target);
5225 #ifdef ASM_OUTPUT_DEF
5226 /* Make name accessible from other files, if appropriate. */
5228 if (TREE_PUBLIC (decl))
5230 globalize_decl (decl);
5231 maybe_assemble_visibility (decl);
5234 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
5235 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
5236 # else
5237 ASM_OUTPUT_DEF (asm_out_file,
5238 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
5239 IDENTIFIER_POINTER (target));
5240 # endif
5241 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
5243 const char *name;
5244 tree *p, t;
5246 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5247 # ifdef ASM_WEAKEN_DECL
5248 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
5249 # else
5250 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
5251 # endif
5252 /* Remove this function from the pending weak list so that
5253 we do not emit multiple .weak directives for it. */
5254 for (p = &weak_decls; (t = *p) ; )
5255 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
5256 *p = TREE_CHAIN (t);
5257 else
5258 p = &TREE_CHAIN (t);
5260 /* Remove weakrefs to the same target from the pending weakref
5261 list, for the same reason. */
5262 for (p = &weakref_targets; (t = *p) ; )
5264 if (DECL_ASSEMBLER_NAME (decl)
5265 == ultimate_transparent_alias_target (&TREE_VALUE (t)))
5266 *p = TREE_CHAIN (t);
5267 else
5268 p = &TREE_CHAIN (t);
5271 #endif
5274 /* First pass of completing pending aliases. Make sure that cgraph knows
5275 which symbols will be required. */
5277 void
5278 finish_aliases_1 (void)
5280 unsigned i;
5281 alias_pair *p;
5283 for (i = 0; VEC_iterate (alias_pair, alias_pairs, i, p); i++)
5285 tree target_decl;
5287 target_decl = find_decl_and_mark_needed (p->decl, p->target);
5288 if (target_decl == NULL)
5290 if (! lookup_attribute ("weakref", DECL_ATTRIBUTES (p->decl)))
5291 error ("%q+D aliased to undefined symbol %qs",
5292 p->decl, IDENTIFIER_POINTER (p->target));
5294 else if (DECL_EXTERNAL (target_decl)
5295 && ! lookup_attribute ("weakref", DECL_ATTRIBUTES (p->decl)))
5296 error ("%q+D aliased to external symbol %qs",
5297 p->decl, IDENTIFIER_POINTER (p->target));
5301 /* Second pass of completing pending aliases. Emit the actual assembly.
5302 This happens at the end of compilation and thus it is assured that the
5303 target symbol has been emitted. */
5305 void
5306 finish_aliases_2 (void)
5308 unsigned i;
5309 alias_pair *p;
5311 for (i = 0; VEC_iterate (alias_pair, alias_pairs, i, p); i++)
5312 do_assemble_alias (p->decl, p->target);
5314 VEC_truncate (alias_pair, alias_pairs, 0);
5317 /* Emit an assembler directive to make the symbol for DECL an alias to
5318 the symbol for TARGET. */
5320 void
5321 assemble_alias (tree decl, tree target)
5323 tree target_decl;
5324 bool is_weakref = false;
5326 if (lookup_attribute ("weakref", DECL_ATTRIBUTES (decl)))
5328 tree alias = DECL_ASSEMBLER_NAME (decl);
5330 is_weakref = true;
5332 ultimate_transparent_alias_target (&target);
5334 if (alias == target)
5335 error ("weakref %q+D ultimately targets itself", decl);
5336 else
5338 #ifndef ASM_OUTPUT_WEAKREF
5339 IDENTIFIER_TRANSPARENT_ALIAS (alias) = 1;
5340 TREE_CHAIN (alias) = target;
5341 #endif
5343 if (TREE_PUBLIC (decl))
5344 error ("weakref %q+D must have static linkage", decl);
5346 else
5348 #if !defined (ASM_OUTPUT_DEF)
5349 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
5350 error ("%Jalias definitions not supported in this configuration", decl);
5351 return;
5352 # else
5353 if (!DECL_WEAK (decl))
5355 error ("%Jonly weak aliases are supported in this configuration", decl);
5356 return;
5358 # endif
5359 #endif
5362 /* We must force creation of DECL_RTL for debug info generation, even though
5363 we don't use it here. */
5364 make_decl_rtl (decl);
5365 TREE_USED (decl) = 1;
5367 /* A quirk of the initial implementation of aliases required that the user
5368 add "extern" to all of them. Which is silly, but now historical. Do
5369 note that the symbol is in fact locally defined. */
5370 if (! is_weakref)
5371 DECL_EXTERNAL (decl) = 0;
5373 /* Allow aliases to aliases. */
5374 if (TREE_CODE (decl) == FUNCTION_DECL)
5375 cgraph_node (decl)->alias = true;
5376 else
5377 varpool_node (decl)->alias = true;
5379 /* If the target has already been emitted, we don't have to queue the
5380 alias. This saves a tad of memory. */
5381 target_decl = find_decl_and_mark_needed (decl, target);
5382 if (target_decl && TREE_ASM_WRITTEN (target_decl))
5383 do_assemble_alias (decl, target);
5384 else
5386 alias_pair *p = VEC_safe_push (alias_pair, gc, alias_pairs, NULL);
5387 p->decl = decl;
5388 p->target = target;
5392 /* Emit an assembler directive to set symbol for DECL visibility to
5393 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
5395 void
5396 default_assemble_visibility (tree decl, int vis)
5398 static const char * const visibility_types[] = {
5399 NULL, "protected", "hidden", "internal"
5402 const char *name, *type;
5404 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5405 type = visibility_types[vis];
5407 #ifdef HAVE_GAS_HIDDEN
5408 fprintf (asm_out_file, "\t.%s\t", type);
5409 assemble_name (asm_out_file, name);
5410 fprintf (asm_out_file, "\n");
5411 #else
5412 warning (OPT_Wattributes, "visibility attribute not supported "
5413 "in this configuration; ignored");
5414 #endif
5417 /* A helper function to call assemble_visibility when needed for a decl. */
5420 maybe_assemble_visibility (tree decl)
5422 enum symbol_visibility vis = DECL_VISIBILITY (decl);
5424 if (vis != VISIBILITY_DEFAULT)
5426 targetm.asm_out.visibility (decl, vis);
5427 return 1;
5429 else
5430 return 0;
5433 /* Returns 1 if the target configuration supports defining public symbols
5434 so that one of them will be chosen at link time instead of generating a
5435 multiply-defined symbol error, whether through the use of weak symbols or
5436 a target-specific mechanism for having duplicates discarded. */
5439 supports_one_only (void)
5441 if (SUPPORTS_ONE_ONLY)
5442 return 1;
5443 return SUPPORTS_WEAK;
5446 /* Set up DECL as a public symbol that can be defined in multiple
5447 translation units without generating a linker error. */
5449 void
5450 make_decl_one_only (tree decl)
5452 gcc_assert (TREE_CODE (decl) == VAR_DECL
5453 || TREE_CODE (decl) == FUNCTION_DECL);
5455 TREE_PUBLIC (decl) = 1;
5457 if (SUPPORTS_ONE_ONLY)
5459 #ifdef MAKE_DECL_ONE_ONLY
5460 MAKE_DECL_ONE_ONLY (decl);
5461 #endif
5462 DECL_ONE_ONLY (decl) = 1;
5464 else if (TREE_CODE (decl) == VAR_DECL
5465 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node))
5466 DECL_COMMON (decl) = 1;
5467 else
5469 gcc_assert (SUPPORTS_WEAK);
5470 DECL_WEAK (decl) = 1;
5474 void
5475 init_varasm_once (void)
5477 section_htab = htab_create_ggc (31, section_entry_hash,
5478 section_entry_eq, NULL);
5479 object_block_htab = htab_create_ggc (31, object_block_entry_hash,
5480 object_block_entry_eq, NULL);
5481 const_desc_htab = htab_create_ggc (1009, const_desc_hash,
5482 const_desc_eq, NULL);
5484 const_alias_set = new_alias_set ();
5485 shared_constant_pool = create_constant_pool ();
5487 #ifdef TEXT_SECTION_ASM_OP
5488 text_section = get_unnamed_section (SECTION_CODE, output_section_asm_op,
5489 TEXT_SECTION_ASM_OP);
5490 #endif
5492 #ifdef DATA_SECTION_ASM_OP
5493 data_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5494 DATA_SECTION_ASM_OP);
5495 #endif
5497 #ifdef SDATA_SECTION_ASM_OP
5498 sdata_section = get_unnamed_section (SECTION_WRITE, output_section_asm_op,
5499 SDATA_SECTION_ASM_OP);
5500 #endif
5502 #ifdef READONLY_DATA_SECTION_ASM_OP
5503 readonly_data_section = get_unnamed_section (0, output_section_asm_op,
5504 READONLY_DATA_SECTION_ASM_OP);
5505 #endif
5507 #ifdef CTORS_SECTION_ASM_OP
5508 ctors_section = get_unnamed_section (0, output_section_asm_op,
5509 CTORS_SECTION_ASM_OP);
5510 #endif
5512 #ifdef DTORS_SECTION_ASM_OP
5513 dtors_section = get_unnamed_section (0, output_section_asm_op,
5514 DTORS_SECTION_ASM_OP);
5515 #endif
5517 #ifdef BSS_SECTION_ASM_OP
5518 bss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5519 output_section_asm_op,
5520 BSS_SECTION_ASM_OP);
5521 #endif
5523 #ifdef SBSS_SECTION_ASM_OP
5524 sbss_section = get_unnamed_section (SECTION_WRITE | SECTION_BSS,
5525 output_section_asm_op,
5526 SBSS_SECTION_ASM_OP);
5527 #endif
5529 tls_comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5530 | SECTION_COMMON, emit_tls_common);
5531 lcomm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5532 | SECTION_COMMON, emit_local);
5533 comm_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS
5534 | SECTION_COMMON, emit_common);
5536 #if defined ASM_OUTPUT_ALIGNED_BSS || defined ASM_OUTPUT_BSS
5537 bss_noswitch_section = get_noswitch_section (SECTION_WRITE | SECTION_BSS,
5538 emit_bss);
5539 #endif
5541 targetm.asm_out.init_sections ();
5543 if (readonly_data_section == NULL)
5544 readonly_data_section = text_section;
5547 enum tls_model
5548 decl_default_tls_model (const_tree decl)
5550 enum tls_model kind;
5551 bool is_local;
5553 is_local = targetm.binds_local_p (decl);
5554 if (!flag_shlib)
5556 if (is_local)
5557 kind = TLS_MODEL_LOCAL_EXEC;
5558 else
5559 kind = TLS_MODEL_INITIAL_EXEC;
5562 /* Local dynamic is inefficient when we're not combining the
5563 parts of the address. */
5564 else if (optimize && is_local)
5565 kind = TLS_MODEL_LOCAL_DYNAMIC;
5566 else
5567 kind = TLS_MODEL_GLOBAL_DYNAMIC;
5568 if (kind < flag_tls_default)
5569 kind = flag_tls_default;
5571 return kind;
5574 /* Select a set of attributes for section NAME based on the properties
5575 of DECL and whether or not RELOC indicates that DECL's initializer
5576 might contain runtime relocations.
5578 We make the section read-only and executable for a function decl,
5579 read-only for a const data decl, and writable for a non-const data decl. */
5581 unsigned int
5582 default_section_type_flags (tree decl, const char *name, int reloc)
5584 unsigned int flags;
5586 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
5587 flags = SECTION_CODE;
5588 else if (decl && decl_readonly_section (decl, reloc))
5589 flags = 0;
5590 else if (current_function_decl
5591 && cfun
5592 && crtl->subsections.unlikely_text_section_name
5593 && strcmp (name, crtl->subsections.unlikely_text_section_name) == 0)
5594 flags = SECTION_CODE;
5595 else if (!decl
5596 && (!current_function_decl || !cfun)
5597 && strcmp (name, UNLIKELY_EXECUTED_TEXT_SECTION_NAME) == 0)
5598 flags = SECTION_CODE;
5599 else
5600 flags = SECTION_WRITE;
5602 if (decl && DECL_ONE_ONLY (decl))
5603 flags |= SECTION_LINKONCE;
5605 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL_P (decl))
5606 flags |= SECTION_TLS | SECTION_WRITE;
5608 if (strcmp (name, ".bss") == 0
5609 || strncmp (name, ".bss.", 5) == 0
5610 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
5611 || strcmp (name, ".sbss") == 0
5612 || strncmp (name, ".sbss.", 6) == 0
5613 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
5614 flags |= SECTION_BSS;
5616 if (strcmp (name, ".tdata") == 0
5617 || strncmp (name, ".tdata.", 7) == 0
5618 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
5619 flags |= SECTION_TLS;
5621 if (strcmp (name, ".tbss") == 0
5622 || strncmp (name, ".tbss.", 6) == 0
5623 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
5624 flags |= SECTION_TLS | SECTION_BSS;
5626 /* These three sections have special ELF types. They are neither
5627 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
5628 want to print a section type (@progbits or @nobits). If someone
5629 is silly enough to emit code or TLS variables to one of these
5630 sections, then don't handle them specially. */
5631 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
5632 && (strcmp (name, ".init_array") == 0
5633 || strcmp (name, ".fini_array") == 0
5634 || strcmp (name, ".preinit_array") == 0))
5635 flags |= SECTION_NOTYPE;
5637 return flags;
5640 /* Return true if the target supports some form of global BSS,
5641 either through bss_noswitch_section, or by selecting a BSS
5642 section in TARGET_ASM_SELECT_SECTION. */
5644 bool
5645 have_global_bss_p (void)
5647 return bss_noswitch_section || targetm.have_switchable_bss_sections;
5650 /* Output assembly to switch to section NAME with attribute FLAGS.
5651 Four variants for common object file formats. */
5653 void
5654 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
5655 unsigned int flags ATTRIBUTE_UNUSED,
5656 tree decl ATTRIBUTE_UNUSED)
5658 /* Some object formats don't support named sections at all. The
5659 front-end should already have flagged this as an error. */
5660 gcc_unreachable ();
5663 void
5664 default_elf_asm_named_section (const char *name, unsigned int flags,
5665 tree decl ATTRIBUTE_UNUSED)
5667 char flagchars[10], *f = flagchars;
5669 /* If we have already declared this section, we can use an
5670 abbreviated form to switch back to it -- unless this section is
5671 part of a COMDAT groups, in which case GAS requires the full
5672 declaration every time. */
5673 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
5674 && (flags & SECTION_DECLARED))
5676 fprintf (asm_out_file, "\t.section\t%s\n", name);
5677 return;
5680 if (!(flags & SECTION_DEBUG))
5681 *f++ = 'a';
5682 if (flags & SECTION_WRITE)
5683 *f++ = 'w';
5684 if (flags & SECTION_CODE)
5685 *f++ = 'x';
5686 if (flags & SECTION_SMALL)
5687 *f++ = 's';
5688 if (flags & SECTION_MERGE)
5689 *f++ = 'M';
5690 if (flags & SECTION_STRINGS)
5691 *f++ = 'S';
5692 if (flags & SECTION_TLS)
5693 *f++ = 'T';
5694 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
5695 *f++ = 'G';
5696 *f = '\0';
5698 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
5700 if (!(flags & SECTION_NOTYPE))
5702 const char *type;
5703 const char *format;
5705 if (flags & SECTION_BSS)
5706 type = "nobits";
5707 else
5708 type = "progbits";
5710 format = ",@%s";
5711 #ifdef ASM_COMMENT_START
5712 /* On platforms that use "@" as the assembly comment character,
5713 use "%" instead. */
5714 if (strcmp (ASM_COMMENT_START, "@") == 0)
5715 format = ",%%%s";
5716 #endif
5717 fprintf (asm_out_file, format, type);
5719 if (flags & SECTION_ENTSIZE)
5720 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
5721 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
5722 fprintf (asm_out_file, ",%s,comdat",
5723 lang_hooks.decls.comdat_group (decl));
5726 putc ('\n', asm_out_file);
5729 void
5730 default_coff_asm_named_section (const char *name, unsigned int flags,
5731 tree decl ATTRIBUTE_UNUSED)
5733 char flagchars[8], *f = flagchars;
5735 if (flags & SECTION_WRITE)
5736 *f++ = 'w';
5737 if (flags & SECTION_CODE)
5738 *f++ = 'x';
5739 *f = '\0';
5741 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
5744 void
5745 default_pe_asm_named_section (const char *name, unsigned int flags,
5746 tree decl)
5748 default_coff_asm_named_section (name, flags, decl);
5750 if (flags & SECTION_LINKONCE)
5752 /* Functions may have been compiled at various levels of
5753 optimization so we can't use `same_size' here.
5754 Instead, have the linker pick one. */
5755 fprintf (asm_out_file, "\t.linkonce %s\n",
5756 (flags & SECTION_CODE ? "discard" : "same_size"));
5760 /* The lame default section selector. */
5762 section *
5763 default_select_section (tree decl, int reloc,
5764 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
5766 if (DECL_P (decl))
5768 if (decl_readonly_section (decl, reloc))
5769 return readonly_data_section;
5771 else if (TREE_CODE (decl) == CONSTRUCTOR)
5773 if (! ((flag_pic && reloc)
5774 || !TREE_READONLY (decl)
5775 || TREE_SIDE_EFFECTS (decl)
5776 || !TREE_CONSTANT (decl)))
5777 return readonly_data_section;
5779 else if (TREE_CODE (decl) == STRING_CST)
5780 return readonly_data_section;
5781 else if (! (flag_pic && reloc))
5782 return readonly_data_section;
5784 return data_section;
5787 enum section_category
5788 categorize_decl_for_section (const_tree decl, int reloc)
5790 enum section_category ret;
5792 if (TREE_CODE (decl) == FUNCTION_DECL)
5793 return SECCAT_TEXT;
5794 else if (TREE_CODE (decl) == STRING_CST)
5796 if (flag_mudflap) /* or !flag_merge_constants */
5797 return SECCAT_RODATA;
5798 else
5799 return SECCAT_RODATA_MERGE_STR;
5801 else if (TREE_CODE (decl) == VAR_DECL)
5803 if (bss_initializer_p (decl))
5804 ret = SECCAT_BSS;
5805 else if (! TREE_READONLY (decl)
5806 || TREE_SIDE_EFFECTS (decl)
5807 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
5809 /* Here the reloc_rw_mask is not testing whether the section should
5810 be read-only or not, but whether the dynamic link will have to
5811 do something. If so, we wish to segregate the data in order to
5812 minimize cache misses inside the dynamic linker. */
5813 if (reloc & targetm.asm_out.reloc_rw_mask ())
5814 ret = reloc == 1 ? SECCAT_DATA_REL_LOCAL : SECCAT_DATA_REL;
5815 else
5816 ret = SECCAT_DATA;
5818 else if (reloc & targetm.asm_out.reloc_rw_mask ())
5819 ret = reloc == 1 ? SECCAT_DATA_REL_RO_LOCAL : SECCAT_DATA_REL_RO;
5820 else if (reloc || flag_merge_constants < 2)
5821 /* C and C++ don't allow different variables to share the same
5822 location. -fmerge-all-constants allows even that (at the
5823 expense of not conforming). */
5824 ret = SECCAT_RODATA;
5825 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
5826 ret = SECCAT_RODATA_MERGE_STR_INIT;
5827 else
5828 ret = SECCAT_RODATA_MERGE_CONST;
5830 else if (TREE_CODE (decl) == CONSTRUCTOR)
5832 if ((reloc & targetm.asm_out.reloc_rw_mask ())
5833 || TREE_SIDE_EFFECTS (decl)
5834 || ! TREE_CONSTANT (decl))
5835 ret = SECCAT_DATA;
5836 else
5837 ret = SECCAT_RODATA;
5839 else
5840 ret = SECCAT_RODATA;
5842 /* There are no read-only thread-local sections. */
5843 if (TREE_CODE (decl) == VAR_DECL && DECL_TLS_MODEL (decl))
5845 if (DECL_TLS_MODEL (decl) == TLS_MODEL_EMULATED)
5847 if (DECL_EMUTLS_VAR_P (decl))
5849 if (targetm.emutls.var_section)
5850 ret = SECCAT_EMUTLS_VAR;
5852 else
5854 if (targetm.emutls.tmpl_prefix)
5855 ret = SECCAT_EMUTLS_TMPL;
5858 /* Note that this would be *just* SECCAT_BSS, except that there's
5859 no concept of a read-only thread-local-data section. */
5860 else if (ret == SECCAT_BSS
5861 || (flag_zero_initialized_in_bss
5862 && initializer_zerop (DECL_INITIAL (decl))))
5863 ret = SECCAT_TBSS;
5864 else
5865 ret = SECCAT_TDATA;
5868 /* If the target uses small data sections, select it. */
5869 else if (targetm.in_small_data_p (decl))
5871 if (ret == SECCAT_BSS)
5872 ret = SECCAT_SBSS;
5873 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
5874 ret = SECCAT_SRODATA;
5875 else
5876 ret = SECCAT_SDATA;
5879 return ret;
5882 bool
5883 decl_readonly_section (const_tree decl, int reloc)
5885 switch (categorize_decl_for_section (decl, reloc))
5887 case SECCAT_RODATA:
5888 case SECCAT_RODATA_MERGE_STR:
5889 case SECCAT_RODATA_MERGE_STR_INIT:
5890 case SECCAT_RODATA_MERGE_CONST:
5891 case SECCAT_SRODATA:
5892 return true;
5893 break;
5894 default:
5895 return false;
5896 break;
5900 /* Select a section based on the above categorization. */
5902 section *
5903 default_elf_select_section (tree decl, int reloc,
5904 unsigned HOST_WIDE_INT align)
5906 const char *sname;
5907 switch (categorize_decl_for_section (decl, reloc))
5909 case SECCAT_TEXT:
5910 /* We're not supposed to be called on FUNCTION_DECLs. */
5911 gcc_unreachable ();
5912 case SECCAT_RODATA:
5913 return readonly_data_section;
5914 case SECCAT_RODATA_MERGE_STR:
5915 return mergeable_string_section (decl, align, 0);
5916 case SECCAT_RODATA_MERGE_STR_INIT:
5917 return mergeable_string_section (DECL_INITIAL (decl), align, 0);
5918 case SECCAT_RODATA_MERGE_CONST:
5919 return mergeable_constant_section (DECL_MODE (decl), align, 0);
5920 case SECCAT_SRODATA:
5921 sname = ".sdata2";
5922 break;
5923 case SECCAT_DATA:
5924 return data_section;
5925 case SECCAT_DATA_REL:
5926 sname = ".data.rel";
5927 break;
5928 case SECCAT_DATA_REL_LOCAL:
5929 sname = ".data.rel.local";
5930 break;
5931 case SECCAT_DATA_REL_RO:
5932 sname = ".data.rel.ro";
5933 break;
5934 case SECCAT_DATA_REL_RO_LOCAL:
5935 sname = ".data.rel.ro.local";
5936 break;
5937 case SECCAT_SDATA:
5938 sname = ".sdata";
5939 break;
5940 case SECCAT_TDATA:
5941 sname = ".tdata";
5942 break;
5943 case SECCAT_BSS:
5944 if (bss_section)
5945 return bss_section;
5946 sname = ".bss";
5947 break;
5948 case SECCAT_SBSS:
5949 sname = ".sbss";
5950 break;
5951 case SECCAT_TBSS:
5952 sname = ".tbss";
5953 break;
5954 case SECCAT_EMUTLS_VAR:
5955 sname = targetm.emutls.var_section;
5956 break;
5957 case SECCAT_EMUTLS_TMPL:
5958 sname = targetm.emutls.tmpl_section;
5959 break;
5960 default:
5961 gcc_unreachable ();
5964 if (!DECL_P (decl))
5965 decl = NULL_TREE;
5966 return get_named_section (decl, sname, reloc);
5969 /* Construct a unique section name based on the decl name and the
5970 categorization performed above. */
5972 void
5973 default_unique_section (tree decl, int reloc)
5975 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
5976 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
5977 const char *prefix, *name, *linkonce;
5978 char *string;
5980 switch (categorize_decl_for_section (decl, reloc))
5982 case SECCAT_TEXT:
5983 prefix = one_only ? ".t" : ".text";
5984 break;
5985 case SECCAT_RODATA:
5986 case SECCAT_RODATA_MERGE_STR:
5987 case SECCAT_RODATA_MERGE_STR_INIT:
5988 case SECCAT_RODATA_MERGE_CONST:
5989 prefix = one_only ? ".r" : ".rodata";
5990 break;
5991 case SECCAT_SRODATA:
5992 prefix = one_only ? ".s2" : ".sdata2";
5993 break;
5994 case SECCAT_DATA:
5995 prefix = one_only ? ".d" : ".data";
5996 break;
5997 case SECCAT_DATA_REL:
5998 prefix = one_only ? ".d.rel" : ".data.rel";
5999 break;
6000 case SECCAT_DATA_REL_LOCAL:
6001 prefix = one_only ? ".d.rel.local" : ".data.rel.local";
6002 break;
6003 case SECCAT_DATA_REL_RO:
6004 prefix = one_only ? ".d.rel.ro" : ".data.rel.ro";
6005 break;
6006 case SECCAT_DATA_REL_RO_LOCAL:
6007 prefix = one_only ? ".d.rel.ro.local" : ".data.rel.ro.local";
6008 break;
6009 case SECCAT_SDATA:
6010 prefix = one_only ? ".s" : ".sdata";
6011 break;
6012 case SECCAT_BSS:
6013 prefix = one_only ? ".b" : ".bss";
6014 break;
6015 case SECCAT_SBSS:
6016 prefix = one_only ? ".sb" : ".sbss";
6017 break;
6018 case SECCAT_TDATA:
6019 prefix = one_only ? ".td" : ".tdata";
6020 break;
6021 case SECCAT_TBSS:
6022 prefix = one_only ? ".tb" : ".tbss";
6023 break;
6024 case SECCAT_EMUTLS_VAR:
6025 prefix = targetm.emutls.var_section;
6026 break;
6027 case SECCAT_EMUTLS_TMPL:
6028 prefix = targetm.emutls.tmpl_section;
6029 break;
6030 default:
6031 gcc_unreachable ();
6034 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
6035 name = targetm.strip_name_encoding (name);
6037 /* If we're using one_only, then there needs to be a .gnu.linkonce
6038 prefix to the section name. */
6039 linkonce = one_only ? ".gnu.linkonce" : "";
6041 string = ACONCAT ((linkonce, prefix, ".", name, NULL));
6043 DECL_SECTION_NAME (decl) = build_string (strlen (string), string);
6046 /* Like compute_reloc_for_constant, except for an RTX. The return value
6047 is a mask for which bit 1 indicates a global relocation, and bit 0
6048 indicates a local relocation. */
6050 static int
6051 compute_reloc_for_rtx_1 (rtx *xp, void *data)
6053 int *preloc = data;
6054 rtx x = *xp;
6056 switch (GET_CODE (x))
6058 case SYMBOL_REF:
6059 *preloc |= SYMBOL_REF_LOCAL_P (x) ? 1 : 2;
6060 break;
6061 case LABEL_REF:
6062 *preloc |= 1;
6063 break;
6064 default:
6065 break;
6068 return 0;
6071 static int
6072 compute_reloc_for_rtx (rtx x)
6074 int reloc;
6076 switch (GET_CODE (x))
6078 case CONST:
6079 case SYMBOL_REF:
6080 case LABEL_REF:
6081 reloc = 0;
6082 for_each_rtx (&x, compute_reloc_for_rtx_1, &reloc);
6083 return reloc;
6085 default:
6086 return 0;
6090 section *
6091 default_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
6092 rtx x,
6093 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
6095 if (compute_reloc_for_rtx (x) & targetm.asm_out.reloc_rw_mask ())
6096 return data_section;
6097 else
6098 return readonly_data_section;
6101 section *
6102 default_elf_select_rtx_section (enum machine_mode mode, rtx x,
6103 unsigned HOST_WIDE_INT align)
6105 int reloc = compute_reloc_for_rtx (x);
6107 /* ??? Handle small data here somehow. */
6109 if (reloc & targetm.asm_out.reloc_rw_mask ())
6111 if (reloc == 1)
6112 return get_named_section (NULL, ".data.rel.ro.local", 1);
6113 else
6114 return get_named_section (NULL, ".data.rel.ro", 3);
6117 return mergeable_constant_section (mode, align, 0);
6120 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
6122 void
6123 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
6125 rtx symbol;
6126 int flags;
6128 /* Careful not to prod global register variables. */
6129 if (!MEM_P (rtl))
6130 return;
6131 symbol = XEXP (rtl, 0);
6132 if (GET_CODE (symbol) != SYMBOL_REF)
6133 return;
6135 flags = SYMBOL_REF_FLAGS (symbol) & SYMBOL_FLAG_HAS_BLOCK_INFO;
6136 if (TREE_CODE (decl) == FUNCTION_DECL)
6137 flags |= SYMBOL_FLAG_FUNCTION;
6138 if (targetm.binds_local_p (decl))
6139 flags |= SYMBOL_FLAG_LOCAL;
6140 if (targetm.have_tls && TREE_CODE (decl) == VAR_DECL
6141 && DECL_THREAD_LOCAL_P (decl))
6142 flags |= DECL_TLS_MODEL (decl) << SYMBOL_FLAG_TLS_SHIFT;
6143 else if (targetm.in_small_data_p (decl))
6144 flags |= SYMBOL_FLAG_SMALL;
6145 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
6146 being PUBLIC, the thing *must* be defined in this translation unit.
6147 Prevent this buglet from being propagated into rtl code as well. */
6148 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
6149 flags |= SYMBOL_FLAG_EXTERNAL;
6151 SYMBOL_REF_FLAGS (symbol) = flags;
6154 /* By default, we do nothing for encode_section_info, so we need not
6155 do anything but discard the '*' marker. */
6157 const char *
6158 default_strip_name_encoding (const char *str)
6160 return str + (*str == '*');
6163 #ifdef ASM_OUTPUT_DEF
6164 /* The default implementation of TARGET_ASM_OUTPUT_ANCHOR. Define the
6165 anchor relative to ".", the current section position. */
6167 void
6168 default_asm_output_anchor (rtx symbol)
6170 char buffer[100];
6172 sprintf (buffer, "*. + " HOST_WIDE_INT_PRINT_DEC,
6173 SYMBOL_REF_BLOCK_OFFSET (symbol));
6174 ASM_OUTPUT_DEF (asm_out_file, XSTR (symbol, 0), buffer);
6176 #endif
6178 /* The default implementation of TARGET_USE_ANCHORS_FOR_SYMBOL_P. */
6180 bool
6181 default_use_anchors_for_symbol_p (const_rtx symbol)
6183 section *sect;
6184 tree decl;
6186 /* Don't use anchors for mergeable sections. The linker might move
6187 the objects around. */
6188 sect = SYMBOL_REF_BLOCK (symbol)->sect;
6189 if (sect->common.flags & SECTION_MERGE)
6190 return false;
6192 /* Don't use anchors for small data sections. The small data register
6193 acts as an anchor for such sections. */
6194 if (sect->common.flags & SECTION_SMALL)
6195 return false;
6197 decl = SYMBOL_REF_DECL (symbol);
6198 if (decl && DECL_P (decl))
6200 /* Don't use section anchors for decls that might be defined by
6201 other modules. */
6202 if (!targetm.binds_local_p (decl))
6203 return false;
6205 /* Don't use section anchors for decls that will be placed in a
6206 small data section. */
6207 /* ??? Ideally, this check would be redundant with the SECTION_SMALL
6208 one above. The problem is that we only use SECTION_SMALL for
6209 sections that should be marked as small in the section directive. */
6210 if (targetm.in_small_data_p (decl))
6211 return false;
6213 return true;
6216 /* Assume ELF-ish defaults, since that's pretty much the most liberal
6217 wrt cross-module name binding. */
6219 bool
6220 default_binds_local_p (const_tree exp)
6222 return default_binds_local_p_1 (exp, flag_shlib);
6225 bool
6226 default_binds_local_p_1 (const_tree exp, int shlib)
6228 bool local_p;
6230 /* A non-decl is an entry in the constant pool. */
6231 if (!DECL_P (exp))
6232 local_p = true;
6233 /* Weakrefs may not bind locally, even though the weakref itself is
6234 always static and therefore local. */
6235 else if (lookup_attribute ("weakref", DECL_ATTRIBUTES (exp)))
6236 local_p = false;
6237 /* Static variables are always local. */
6238 else if (! TREE_PUBLIC (exp))
6239 local_p = true;
6240 /* A variable is local if the user has said explicitly that it will
6241 be. */
6242 else if (DECL_VISIBILITY_SPECIFIED (exp)
6243 && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6244 local_p = true;
6245 /* Variables defined outside this object might not be local. */
6246 else if (DECL_EXTERNAL (exp))
6247 local_p = false;
6248 /* If defined in this object and visibility is not default, must be
6249 local. */
6250 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
6251 local_p = true;
6252 /* Default visibility weak data can be overridden by a strong symbol
6253 in another module and so are not local. */
6254 else if (DECL_WEAK (exp))
6255 local_p = false;
6256 /* If PIC, then assume that any global name can be overridden by
6257 symbols resolved from other modules, unless we are compiling with
6258 -fwhole-program, which assumes that names are local. */
6259 else if (shlib)
6260 local_p = flag_whole_program;
6261 /* Uninitialized COMMON variable may be unified with symbols
6262 resolved from other modules. */
6263 else if (DECL_COMMON (exp)
6264 && (DECL_INITIAL (exp) == NULL
6265 || DECL_INITIAL (exp) == error_mark_node))
6266 local_p = false;
6267 /* Otherwise we're left with initialized (or non-common) global data
6268 which is of necessity defined locally. */
6269 else
6270 local_p = true;
6272 return local_p;
6275 /* Determine whether or not a pointer mode is valid. Assume defaults
6276 of ptr_mode or Pmode - can be overridden. */
6277 bool
6278 default_valid_pointer_mode (enum machine_mode mode)
6280 return (mode == ptr_mode || mode == Pmode);
6283 /* Default function to output code that will globalize a label. A
6284 target must define GLOBAL_ASM_OP or provide its own function to
6285 globalize a label. */
6286 #ifdef GLOBAL_ASM_OP
6287 void
6288 default_globalize_label (FILE * stream, const char *name)
6290 fputs (GLOBAL_ASM_OP, stream);
6291 assemble_name (stream, name);
6292 putc ('\n', stream);
6294 #endif /* GLOBAL_ASM_OP */
6296 /* Default function to output code that will globalize a declaration. */
6297 void
6298 default_globalize_decl_name (FILE * stream, tree decl)
6300 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
6301 targetm.asm_out.globalize_label (stream, name);
6304 /* Default function to output a label for unwind information. The
6305 default is to do nothing. A target that needs nonlocal labels for
6306 unwind information must provide its own function to do this. */
6307 void
6308 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
6309 tree decl ATTRIBUTE_UNUSED,
6310 int for_eh ATTRIBUTE_UNUSED,
6311 int empty ATTRIBUTE_UNUSED)
6315 /* Default function to output a label to divide up the exception table.
6316 The default is to do nothing. A target that needs/wants to divide
6317 up the table must provide it's own function to do this. */
6318 void
6319 default_emit_except_table_label (FILE * stream ATTRIBUTE_UNUSED)
6323 /* This is how to output an internal numbered label where PREFIX is
6324 the class of label and LABELNO is the number within the class. */
6326 void
6327 default_internal_label (FILE *stream, const char *prefix,
6328 unsigned long labelno)
6330 char *const buf = alloca (40 + strlen (prefix));
6331 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
6332 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
6335 /* This is the default behavior at the beginning of a file. It's
6336 controlled by two other target-hook toggles. */
6337 void
6338 default_file_start (void)
6340 if (targetm.file_start_app_off && !flag_verbose_asm)
6341 fputs (ASM_APP_OFF, asm_out_file);
6343 if (targetm.file_start_file_directive)
6344 output_file_directive (asm_out_file, main_input_filename);
6347 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
6348 which emits a special section directive used to indicate whether or
6349 not this object file needs an executable stack. This is primarily
6350 a GNU extension to ELF but could be used on other targets. */
6352 int trampolines_created;
6354 void
6355 file_end_indicate_exec_stack (void)
6357 unsigned int flags = SECTION_DEBUG;
6358 if (trampolines_created)
6359 flags |= SECTION_CODE;
6361 switch_to_section (get_section (".note.GNU-stack", flags, NULL));
6364 /* Output DIRECTIVE (a C string) followed by a newline. This is used as
6365 a get_unnamed_section callback. */
6367 void
6368 output_section_asm_op (const void *directive)
6370 fprintf (asm_out_file, "%s\n", (const char *) directive);
6373 /* Emit assembly code to switch to section NEW_SECTION. Do nothing if
6374 the current section is NEW_SECTION. */
6376 void
6377 switch_to_section (section *new_section)
6379 if (in_section == new_section)
6380 return;
6382 if (new_section->common.flags & SECTION_FORGET)
6383 in_section = NULL;
6384 else
6385 in_section = new_section;
6387 switch (SECTION_STYLE (new_section))
6389 case SECTION_NAMED:
6390 if (cfun
6391 && !crtl->subsections.unlikely_text_section_name
6392 && strcmp (new_section->named.name,
6393 UNLIKELY_EXECUTED_TEXT_SECTION_NAME) == 0)
6394 crtl->subsections.unlikely_text_section_name = UNLIKELY_EXECUTED_TEXT_SECTION_NAME;
6396 targetm.asm_out.named_section (new_section->named.name,
6397 new_section->named.common.flags,
6398 new_section->named.decl);
6399 break;
6401 case SECTION_UNNAMED:
6402 new_section->unnamed.callback (new_section->unnamed.data);
6403 break;
6405 case SECTION_NOSWITCH:
6406 gcc_unreachable ();
6407 break;
6410 new_section->common.flags |= SECTION_DECLARED;
6413 /* If block symbol SYMBOL has not yet been assigned an offset, place
6414 it at the end of its block. */
6416 void
6417 place_block_symbol (rtx symbol)
6419 unsigned HOST_WIDE_INT size, mask, offset;
6420 struct constant_descriptor_rtx *desc;
6421 unsigned int alignment;
6422 struct object_block *block;
6423 tree decl;
6425 gcc_assert (SYMBOL_REF_BLOCK (symbol));
6426 if (SYMBOL_REF_BLOCK_OFFSET (symbol) >= 0)
6427 return;
6429 /* Work out the symbol's size and alignment. */
6430 if (CONSTANT_POOL_ADDRESS_P (symbol))
6432 desc = SYMBOL_REF_CONSTANT (symbol);
6433 alignment = desc->align;
6434 size = GET_MODE_SIZE (desc->mode);
6436 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
6438 decl = SYMBOL_REF_DECL (symbol);
6439 alignment = get_constant_alignment (decl);
6440 size = get_constant_size (decl);
6442 else
6444 decl = SYMBOL_REF_DECL (symbol);
6445 alignment = DECL_ALIGN (decl);
6446 size = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
6449 /* Calculate the object's offset from the start of the block. */
6450 block = SYMBOL_REF_BLOCK (symbol);
6451 mask = alignment / BITS_PER_UNIT - 1;
6452 offset = (block->size + mask) & ~mask;
6453 SYMBOL_REF_BLOCK_OFFSET (symbol) = offset;
6455 /* Record the block's new alignment and size. */
6456 block->alignment = MAX (block->alignment, alignment);
6457 block->size = offset + size;
6459 VEC_safe_push (rtx, gc, block->objects, symbol);
6462 /* Return the anchor that should be used to address byte offset OFFSET
6463 from the first object in BLOCK. MODEL is the TLS model used
6464 to access it. */
6467 get_section_anchor (struct object_block *block, HOST_WIDE_INT offset,
6468 enum tls_model model)
6470 char label[100];
6471 unsigned int begin, middle, end;
6472 unsigned HOST_WIDE_INT min_offset, max_offset, range, bias, delta;
6473 rtx anchor;
6475 /* Work out the anchor's offset. Use an offset of 0 for the first
6476 anchor so that we don't pessimize the case where we take the address
6477 of a variable at the beginning of the block. This is particularly
6478 useful when a block has only one variable assigned to it.
6480 We try to place anchors RANGE bytes apart, so there can then be
6481 anchors at +/-RANGE, +/-2 * RANGE, and so on, up to the limits of
6482 a ptr_mode offset. With some target settings, the lowest such
6483 anchor might be out of range for the lowest ptr_mode offset;
6484 likewise the highest anchor for the highest offset. Use anchors
6485 at the extreme ends of the ptr_mode range in such cases.
6487 All arithmetic uses unsigned integers in order to avoid
6488 signed overflow. */
6489 max_offset = (unsigned HOST_WIDE_INT) targetm.max_anchor_offset;
6490 min_offset = (unsigned HOST_WIDE_INT) targetm.min_anchor_offset;
6491 range = max_offset - min_offset + 1;
6492 if (range == 0)
6493 offset = 0;
6494 else
6496 bias = 1 << (GET_MODE_BITSIZE (ptr_mode) - 1);
6497 if (offset < 0)
6499 delta = -(unsigned HOST_WIDE_INT) offset + max_offset;
6500 delta -= delta % range;
6501 if (delta > bias)
6502 delta = bias;
6503 offset = (HOST_WIDE_INT) (-delta);
6505 else
6507 delta = (unsigned HOST_WIDE_INT) offset - min_offset;
6508 delta -= delta % range;
6509 if (delta > bias - 1)
6510 delta = bias - 1;
6511 offset = (HOST_WIDE_INT) delta;
6515 /* Do a binary search to see if there's already an anchor we can use.
6516 Set BEGIN to the new anchor's index if not. */
6517 begin = 0;
6518 end = VEC_length (rtx, block->anchors);
6519 while (begin != end)
6521 middle = (end + begin) / 2;
6522 anchor = VEC_index (rtx, block->anchors, middle);
6523 if (SYMBOL_REF_BLOCK_OFFSET (anchor) > offset)
6524 end = middle;
6525 else if (SYMBOL_REF_BLOCK_OFFSET (anchor) < offset)
6526 begin = middle + 1;
6527 else if (SYMBOL_REF_TLS_MODEL (anchor) > model)
6528 end = middle;
6529 else if (SYMBOL_REF_TLS_MODEL (anchor) < model)
6530 begin = middle + 1;
6531 else
6532 return anchor;
6535 /* Create a new anchor with a unique label. */
6536 ASM_GENERATE_INTERNAL_LABEL (label, "LANCHOR", anchor_labelno++);
6537 anchor = create_block_symbol (ggc_strdup (label), block, offset);
6538 SYMBOL_REF_FLAGS (anchor) |= SYMBOL_FLAG_LOCAL | SYMBOL_FLAG_ANCHOR;
6539 SYMBOL_REF_FLAGS (anchor) |= model << SYMBOL_FLAG_TLS_SHIFT;
6541 /* Insert it at index BEGIN. */
6542 VEC_safe_insert (rtx, gc, block->anchors, begin, anchor);
6543 return anchor;
6546 /* Output the objects in BLOCK. */
6548 static void
6549 output_object_block (struct object_block *block)
6551 struct constant_descriptor_rtx *desc;
6552 unsigned int i;
6553 HOST_WIDE_INT offset;
6554 tree decl;
6555 rtx symbol;
6557 if (block->objects == NULL)
6558 return;
6560 /* Switch to the section and make sure that the first byte is
6561 suitably aligned. */
6562 switch_to_section (block->sect);
6563 assemble_align (block->alignment);
6565 /* Define the values of all anchors relative to the current section
6566 position. */
6567 for (i = 0; VEC_iterate (rtx, block->anchors, i, symbol); i++)
6568 targetm.asm_out.output_anchor (symbol);
6570 /* Output the objects themselves. */
6571 offset = 0;
6572 for (i = 0; VEC_iterate (rtx, block->objects, i, symbol); i++)
6574 /* Move to the object's offset, padding with zeros if necessary. */
6575 assemble_zeros (SYMBOL_REF_BLOCK_OFFSET (symbol) - offset);
6576 offset = SYMBOL_REF_BLOCK_OFFSET (symbol);
6577 if (CONSTANT_POOL_ADDRESS_P (symbol))
6579 desc = SYMBOL_REF_CONSTANT (symbol);
6580 output_constant_pool_1 (desc, 1);
6581 offset += GET_MODE_SIZE (desc->mode);
6583 else if (TREE_CONSTANT_POOL_ADDRESS_P (symbol))
6585 decl = SYMBOL_REF_DECL (symbol);
6586 assemble_constant_contents (decl, XSTR (symbol, 0),
6587 get_constant_alignment (decl));
6588 offset += get_constant_size (decl);
6590 else
6592 decl = SYMBOL_REF_DECL (symbol);
6593 assemble_variable_contents (decl, XSTR (symbol, 0), false);
6594 offset += tree_low_cst (DECL_SIZE_UNIT (decl), 1);
6599 /* A htab_traverse callback used to call output_object_block for
6600 each member of object_block_htab. */
6602 static int
6603 output_object_block_htab (void **slot, void *data ATTRIBUTE_UNUSED)
6605 output_object_block ((struct object_block *) (*slot));
6606 return 1;
6609 /* Output the definitions of all object_blocks. */
6611 void
6612 output_object_blocks (void)
6614 htab_traverse (object_block_htab, output_object_block_htab, NULL);
6617 /* This function provides a possible implementation of the
6618 TARGET_ASM_RECORD_GCC_SWITCHES target hook for ELF targets. When triggered
6619 by -frecord-gcc-switches it creates a new mergeable, string section in the
6620 assembler output file called TARGET_ASM_RECORD_GCC_SWITCHES_SECTION which
6621 contains the switches in ASCII format.
6623 FIXME: This code does not correctly handle double quote characters
6624 that appear inside strings, (it strips them rather than preserving them).
6625 FIXME: ASM_OUTPUT_ASCII, as defined in config/elfos.h will not emit NUL
6626 characters - instead it treats them as sub-string separators. Since
6627 we want to emit NUL strings terminators into the object file we have to use
6628 ASM_OUTPUT_SKIP. */
6631 elf_record_gcc_switches (print_switch_type type, const char * name)
6633 static char buffer[1024];
6635 /* This variable is used as part of a simplistic heuristic to detect
6636 command line switches which take an argument:
6638 "If a command line option does not start with a dash then
6639 it is an argument for the previous command line option."
6641 This fails in the case of the command line option which is the name
6642 of the file to compile, but otherwise it is pretty reasonable. */
6643 static bool previous_name_held_back = FALSE;
6645 switch (type)
6647 case SWITCH_TYPE_PASSED:
6648 if (* name != '-')
6650 if (previous_name_held_back)
6652 unsigned int len = strlen (buffer);
6654 snprintf (buffer + len, sizeof buffer - len, " %s", name);
6655 ASM_OUTPUT_ASCII (asm_out_file, buffer, strlen (buffer));
6656 ASM_OUTPUT_SKIP (asm_out_file, (unsigned HOST_WIDE_INT) 1);
6657 previous_name_held_back = FALSE;
6659 else
6661 strncpy (buffer, name, sizeof buffer);
6662 ASM_OUTPUT_ASCII (asm_out_file, buffer, strlen (buffer));
6663 ASM_OUTPUT_SKIP (asm_out_file, (unsigned HOST_WIDE_INT) 1);
6666 else
6668 if (previous_name_held_back)
6670 ASM_OUTPUT_ASCII (asm_out_file, buffer, strlen (buffer));
6671 ASM_OUTPUT_SKIP (asm_out_file, (unsigned HOST_WIDE_INT) 1);
6674 strncpy (buffer, name, sizeof buffer);
6675 previous_name_held_back = TRUE;
6677 break;
6679 case SWITCH_TYPE_DESCRIPTIVE:
6680 if (name == NULL)
6682 /* Distinguish between invocations where name is NULL. */
6683 static bool started = false;
6685 if (started)
6687 if (previous_name_held_back)
6689 ASM_OUTPUT_ASCII (asm_out_file, buffer, strlen (buffer));
6690 ASM_OUTPUT_SKIP (asm_out_file, (unsigned HOST_WIDE_INT) 1);
6693 else
6695 section * sec;
6697 sec = get_section (targetm.asm_out.record_gcc_switches_section,
6698 SECTION_DEBUG
6699 | SECTION_MERGE
6700 | SECTION_STRINGS
6701 | (SECTION_ENTSIZE & 1),
6702 NULL);
6703 switch_to_section (sec);
6704 started = true;
6708 default:
6709 break;
6712 /* The return value is currently ignored by the caller, but must be 0.
6713 For -fverbose-asm the return value would be the number of characters
6714 emitted into the assembler file. */
6715 return 0;
6718 /* Emit text to declare externally defined symbols. It is needed to
6719 properly support non-default visibility. */
6720 void
6721 default_elf_asm_output_external (FILE *file ATTRIBUTE_UNUSED,
6722 tree decl,
6723 const char *name ATTRIBUTE_UNUSED)
6725 /* We output the name if and only if TREE_SYMBOL_REFERENCED is
6726 set in order to avoid putting out names that are never really
6727 used. */
6728 if (TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (decl))
6729 && targetm.binds_local_p (decl))
6730 maybe_assemble_visibility (decl);
6733 #include "gt-varasm.h"