* common.opt (-Wattributes): New. Default true.
[official-gcc.git] / gcc / varasm.c
blob8192a7a5981b86b4967175bb1877385b9a124da9
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
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 2, 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 COPYING. If not, write to the Free
20 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
21 02111-1307, USA. */
24 /* This file handles generation of all the assembler code
25 *except* the instructions of a function.
26 This includes declarations of variables and their initial values.
28 We also output the assembler code for constants stored in memory
29 and are responsible for combining constants with the same value. */
31 #include "config.h"
32 #include "system.h"
33 #include "coretypes.h"
34 #include "tm.h"
35 #include "rtl.h"
36 #include "tree.h"
37 #include "flags.h"
38 #include "function.h"
39 #include "expr.h"
40 #include "hard-reg-set.h"
41 #include "regs.h"
42 #include "real.h"
43 #include "output.h"
44 #include "toplev.h"
45 #include "hashtab.h"
46 #include "c-pragma.h"
47 #include "ggc.h"
48 #include "langhooks.h"
49 #include "tm_p.h"
50 #include "debug.h"
51 #include "target.h"
52 #include "tree-mudflap.h"
53 #include "cgraph.h"
54 #include "cfglayout.h"
55 #include "basic-block.h"
57 #ifdef XCOFF_DEBUGGING_INFO
58 #include "xcoffout.h" /* Needed for external data
59 declarations for e.g. AIX 4.x. */
60 #endif
62 /* The (assembler) name of the first globally-visible object output. */
63 const char *first_global_object_name;
64 const char *weak_global_object_name;
66 struct addr_const;
67 struct constant_descriptor_rtx;
68 struct rtx_constant_pool;
70 struct varasm_status GTY(())
72 /* If we're using a per-function constant pool, this is it. */
73 struct rtx_constant_pool *pool;
75 /* Number of tree-constants deferred during the expansion of this
76 function. */
77 unsigned int deferred_constants;
80 #define n_deferred_constants (cfun->varasm->deferred_constants)
82 /* Number for making the label on the next
83 constant that is stored in memory. */
85 static GTY(()) int const_labelno;
87 /* Carry information from ASM_DECLARE_OBJECT_NAME
88 to ASM_FINISH_DECLARE_OBJECT. */
90 int size_directive_output;
92 /* The last decl for which assemble_variable was called,
93 if it did ASM_DECLARE_OBJECT_NAME.
94 If the last call to assemble_variable didn't do that,
95 this holds 0. */
97 tree last_assemble_variable_decl;
99 /* The following global variable indicates if the first basic block
100 in a function belongs to the cold partition or not. */
102 bool first_function_block_is_cold;
104 /* We give all constants their own alias set. Perhaps redundant with
105 MEM_READONLY_P, but pre-dates it. */
107 static HOST_WIDE_INT const_alias_set;
109 static const char *strip_reg_name (const char *);
110 static int contains_pointers_p (tree);
111 #ifdef ASM_OUTPUT_EXTERNAL
112 static bool incorporeal_function_p (tree);
113 #endif
114 static void decode_addr_const (tree, struct addr_const *);
115 static hashval_t const_desc_hash (const void *);
116 static int const_desc_eq (const void *, const void *);
117 static hashval_t const_hash_1 (const tree);
118 static int compare_constant (const tree, const tree);
119 static tree copy_constant (tree);
120 static void output_constant_def_contents (rtx);
121 static void output_addressed_constants (tree);
122 static unsigned HOST_WIDE_INT array_size_for_constructor (tree);
123 static unsigned min_align (unsigned, unsigned);
124 static void output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int);
125 static void globalize_decl (tree);
126 static void maybe_assemble_visibility (tree);
127 static int in_named_entry_eq (const void *, const void *);
128 static hashval_t in_named_entry_hash (const void *);
129 static void initialize_cold_section_name (void);
130 #ifdef BSS_SECTION_ASM_OP
131 #ifdef ASM_OUTPUT_BSS
132 static void asm_output_bss (FILE *, tree, const char *,
133 unsigned HOST_WIDE_INT, unsigned HOST_WIDE_INT);
134 #endif
135 #ifdef ASM_OUTPUT_ALIGNED_BSS
136 static void asm_output_aligned_bss (FILE *, tree, const char *,
137 unsigned HOST_WIDE_INT, int)
138 ATTRIBUTE_UNUSED;
139 #endif
140 #endif /* BSS_SECTION_ASM_OP */
141 static bool asm_emit_uninitialised (tree, const char*,
142 unsigned HOST_WIDE_INT,
143 unsigned HOST_WIDE_INT);
144 static void mark_weak (tree);
146 static GTY(()) enum in_section in_section = no_section;
147 enum in_section last_text_section;
149 /* Return a nonzero value if DECL has a section attribute. */
150 #ifndef IN_NAMED_SECTION
151 #define IN_NAMED_SECTION(DECL) \
152 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \
153 && DECL_SECTION_NAME (DECL) != NULL_TREE)
154 #endif
156 /* Text of section name when in_section == in_named. */
157 static GTY(()) const char *in_named_name;
158 const char *last_text_section_name;
160 /* Hash table of flags that have been used for a particular named section. */
162 struct in_named_entry GTY(())
164 const char *name;
165 unsigned int flags;
166 bool declared;
169 static GTY((param_is (struct in_named_entry))) htab_t in_named_htab;
171 /* Define functions like text_section for any extra sections. */
172 #ifdef EXTRA_SECTION_FUNCTIONS
173 EXTRA_SECTION_FUNCTIONS
174 #endif
176 static void
177 initialize_cold_section_name (void)
179 const char *name;
180 const char *stripped_name;
181 char *buffer;
183 gcc_assert (cfun && current_function_decl);
184 if (cfun->unlikely_text_section_name)
185 return;
187 if (flag_function_sections && DECL_SECTION_NAME (current_function_decl))
189 name = alloca (TREE_STRING_LENGTH (DECL_SECTION_NAME
190 (current_function_decl)));
191 strcpy ((char *) name, TREE_STRING_POINTER (DECL_SECTION_NAME
192 (current_function_decl)));
193 stripped_name = targetm.strip_name_encoding (name);
194 buffer = ACONCAT ((stripped_name, "_unlikely", NULL));
195 cfun->unlikely_text_section_name = ggc_strdup (buffer);
197 else
198 cfun->unlikely_text_section_name = UNLIKELY_EXECUTED_TEXT_SECTION_NAME;
201 /* Tell assembler to switch to text section. */
203 void
204 text_section (void)
206 if (in_section != in_text)
208 in_section = in_text;
209 last_text_section = in_text;
210 fprintf (asm_out_file, "%s\n", TEXT_SECTION_ASM_OP);
214 /* Tell assembler to switch to unlikely-to-be-executed text section. */
216 void
217 unlikely_text_section (void)
219 if (cfun)
221 if (!cfun->unlikely_text_section_name)
222 initialize_cold_section_name ();
224 if (flag_function_sections
225 || ((in_section != in_unlikely_executed_text)
226 && (in_section != in_named
227 || (strcmp (in_named_name, cfun->unlikely_text_section_name)
228 != 0))))
230 named_section (NULL_TREE, cfun->unlikely_text_section_name, 0);
231 in_section = in_unlikely_executed_text;
232 last_text_section = in_unlikely_executed_text;
235 else
237 named_section (NULL_TREE, UNLIKELY_EXECUTED_TEXT_SECTION_NAME, 0);
238 in_section = in_unlikely_executed_text;
239 last_text_section = in_unlikely_executed_text;
243 /* Tell assembler to switch to data section. */
245 void
246 data_section (void)
248 if (in_section != in_data)
250 in_section = in_data;
251 fprintf (asm_out_file, "%s\n", DATA_SECTION_ASM_OP);
255 /* Tell assembler to switch to read-only data section. This is normally
256 the text section. */
258 void
259 readonly_data_section (void)
261 #ifdef READONLY_DATA_SECTION
262 READONLY_DATA_SECTION (); /* Note this can call data_section. */
263 #else
264 #ifdef READONLY_DATA_SECTION_ASM_OP
265 if (in_section != in_readonly_data)
267 in_section = in_readonly_data;
268 fputs (READONLY_DATA_SECTION_ASM_OP, asm_out_file);
269 fputc ('\n', asm_out_file);
271 #else
272 text_section ();
273 #endif
274 #endif
277 /* Determine if we're in the text section. */
280 in_text_section (void)
282 return in_section == in_text;
285 /* Determine if we're in the unlikely-to-be-executed text section. */
288 in_unlikely_text_section (void)
290 bool ret_val;
292 if (cfun)
294 ret_val = ((in_section == in_unlikely_executed_text)
295 || (in_section == in_named
296 && cfun->unlikely_text_section_name
297 && strcmp (in_named_name,
298 cfun->unlikely_text_section_name) == 0));
300 else
302 ret_val = ((in_section == in_unlikely_executed_text)
303 || (in_section == in_named
304 && strcmp (in_named_name,
305 UNLIKELY_EXECUTED_TEXT_SECTION_NAME) == 0));
308 return ret_val;
311 /* Determine if we're in the data section. */
314 in_data_section (void)
316 return in_section == in_data;
319 /* Helper routines for maintaining in_named_htab. */
321 static int
322 in_named_entry_eq (const void *p1, const void *p2)
324 const struct in_named_entry *old = p1;
325 const char *new = p2;
327 return strcmp (old->name, new) == 0;
330 static hashval_t
331 in_named_entry_hash (const void *p)
333 const struct in_named_entry *old = p;
334 return htab_hash_string (old->name);
337 /* If SECTION has been seen before as a named section, return the flags
338 that were used. Otherwise, return 0. Note, that 0 is a perfectly valid
339 set of flags for a section to have, so 0 does not mean that the section
340 has not been seen. */
342 static unsigned int
343 get_named_section_flags (const char *section)
345 struct in_named_entry **slot;
347 slot = (struct in_named_entry **)
348 htab_find_slot_with_hash (in_named_htab, section,
349 htab_hash_string (section), NO_INSERT);
351 return slot ? (*slot)->flags : 0;
354 /* Returns true if the section has been declared before. Sets internal
355 flag on this section in in_named_hash so subsequent calls on this
356 section will return false. */
358 bool
359 named_section_first_declaration (const char *name)
361 struct in_named_entry **slot;
363 slot = (struct in_named_entry **)
364 htab_find_slot_with_hash (in_named_htab, name,
365 htab_hash_string (name), NO_INSERT);
366 if (! (*slot)->declared)
368 (*slot)->declared = true;
369 return true;
371 else
373 return false;
378 /* Record FLAGS for SECTION. If SECTION was previously recorded with a
379 different set of flags, return false. */
381 bool
382 set_named_section_flags (const char *section, unsigned int flags)
384 struct in_named_entry **slot, *entry;
386 slot = (struct in_named_entry **)
387 htab_find_slot_with_hash (in_named_htab, section,
388 htab_hash_string (section), INSERT);
389 entry = *slot;
391 if (!entry)
393 entry = ggc_alloc (sizeof (*entry));
394 *slot = entry;
395 entry->name = ggc_strdup (section);
396 entry->flags = flags;
397 entry->declared = false;
399 else if (entry->flags != flags)
400 return false;
402 return true;
405 /* Tell assembler to change to section NAME with attributes FLAGS. If
406 DECL is non-NULL, it is the VAR_DECL or FUNCTION_DECL with which
407 this section is associated. */
409 void
410 named_section_real (const char *name, unsigned int flags, tree decl)
412 if (in_section != in_named || strcmp (name, in_named_name) != 0)
414 bool unchanged = set_named_section_flags (name, flags);
416 gcc_assert (unchanged);
418 targetm.asm_out.named_section (name, flags, decl);
420 if (flags & SECTION_FORGET)
421 in_section = no_section;
422 else
424 in_named_name = ggc_strdup (name);
425 in_section = in_named;
429 if (in_text_section () || in_unlikely_text_section ())
431 last_text_section = in_section;
432 last_text_section_name = name;
436 /* Tell assembler to change to section NAME for DECL.
437 If DECL is NULL, just switch to section NAME.
438 If NAME is NULL, get the name from DECL.
439 If RELOC is 1, the initializer for DECL contains relocs. */
441 void
442 named_section (tree decl, const char *name, int reloc)
444 unsigned int flags;
446 gcc_assert (!decl || DECL_P (decl));
447 if (name == NULL)
448 name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
450 if (strcmp (name, UNLIKELY_EXECUTED_TEXT_SECTION_NAME) == 0
451 && cfun
452 && ! cfun->unlikely_text_section_name)
453 cfun->unlikely_text_section_name = UNLIKELY_EXECUTED_TEXT_SECTION_NAME;
455 flags = targetm.section_type_flags (decl, name, reloc);
457 /* Sanity check user variables for flag changes. Non-user
458 section flag changes will die in named_section_flags.
459 However, don't complain if SECTION_OVERRIDE is set.
460 We trust that the setter knows that it is safe to ignore
461 the default flags for this decl. */
462 if (decl && ! set_named_section_flags (name, flags))
464 flags = get_named_section_flags (name);
465 if ((flags & SECTION_OVERRIDE) == 0)
466 error ("%J%D causes a section type conflict", decl, decl);
469 named_section_real (name, flags, decl);
472 /* If required, set DECL_SECTION_NAME to a unique name. */
474 void
475 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
476 int flag_function_or_data_sections)
478 if (DECL_SECTION_NAME (decl) == NULL_TREE
479 && targetm.have_named_sections
480 && (flag_function_or_data_sections
481 || DECL_ONE_ONLY (decl)))
482 targetm.asm_out.unique_section (decl, reloc);
485 #ifdef BSS_SECTION_ASM_OP
487 /* Tell the assembler to switch to the bss section. */
489 void
490 bss_section (void)
492 if (in_section != in_bss)
494 fprintf (asm_out_file, "%s\n", BSS_SECTION_ASM_OP);
495 in_section = in_bss;
499 #ifdef ASM_OUTPUT_BSS
501 /* Utility function for ASM_OUTPUT_BSS for targets to use if
502 they don't support alignments in .bss.
503 ??? It is believed that this function will work in most cases so such
504 support is localized here. */
506 static void
507 asm_output_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
508 const char *name,
509 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
510 unsigned HOST_WIDE_INT rounded)
512 targetm.asm_out.globalize_label (file, name);
513 bss_section ();
514 #ifdef ASM_DECLARE_OBJECT_NAME
515 last_assemble_variable_decl = decl;
516 ASM_DECLARE_OBJECT_NAME (file, name, decl);
517 #else
518 /* Standard thing is just output label for the object. */
519 ASM_OUTPUT_LABEL (file, name);
520 #endif /* ASM_DECLARE_OBJECT_NAME */
521 ASM_OUTPUT_SKIP (file, rounded ? rounded : 1);
524 #endif
526 #ifdef ASM_OUTPUT_ALIGNED_BSS
528 /* Utility function for targets to use in implementing
529 ASM_OUTPUT_ALIGNED_BSS.
530 ??? It is believed that this function will work in most cases so such
531 support is localized here. */
533 static void
534 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
535 const char *name, unsigned HOST_WIDE_INT size,
536 int align)
538 bss_section ();
539 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
540 #ifdef ASM_DECLARE_OBJECT_NAME
541 last_assemble_variable_decl = decl;
542 ASM_DECLARE_OBJECT_NAME (file, name, decl);
543 #else
544 /* Standard thing is just output label for the object. */
545 ASM_OUTPUT_LABEL (file, name);
546 #endif /* ASM_DECLARE_OBJECT_NAME */
547 ASM_OUTPUT_SKIP (file, size ? size : 1);
550 #endif
552 #endif /* BSS_SECTION_ASM_OP */
554 /* Switch to the section for function DECL.
556 If DECL is NULL_TREE, switch to the text section. We can be passed
557 NULL_TREE under some circumstances by dbxout.c at least. */
559 void
560 function_section (tree decl)
562 int reloc = 0;
564 if (first_function_block_is_cold)
565 reloc = 1;
567 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
568 targetm.asm_out.select_section (decl, reloc, DECL_ALIGN (decl));
569 #else
570 if (decl != NULL_TREE
571 && DECL_SECTION_NAME (decl) != NULL_TREE
572 && targetm.have_named_sections)
573 named_section (decl, (char *) 0, 0);
574 else
575 text_section ();
576 #endif
579 void
580 current_function_section (tree decl)
582 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
583 int reloc = 0;
585 if (in_unlikely_text_section ()
586 || last_text_section == in_unlikely_executed_text)
587 reloc = 1;
589 targetm.asm_out.select_section (decl, reloc, DECL_ALIGN (decl));
590 #else
591 if (last_text_section == in_unlikely_executed_text)
592 unlikely_text_section ();
593 else if (last_text_section == in_text)
594 text_section ();
595 else if (last_text_section == in_named
596 && targetm.have_named_sections)
597 named_section (NULL_TREE, last_text_section_name, 0);
598 else
599 function_section (decl);
600 #endif
603 /* Switch to read-only data section associated with function DECL. */
605 void
606 default_function_rodata_section (tree decl)
608 if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
610 const char *name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
612 if (DECL_ONE_ONLY (decl) && HAVE_COMDAT_GROUP)
614 size_t len = strlen (name) + 3;
615 char* rname = alloca (len);
617 strcpy (rname, ".rodata");
618 strcat (rname, name + 5);
619 named_section_real (rname, SECTION_LINKONCE, decl);
620 return;
622 /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo. */
623 else if (DECL_ONE_ONLY (decl)
624 && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
626 size_t len = strlen (name) + 1;
627 char *rname = alloca (len);
629 memcpy (rname, name, len);
630 rname[14] = 'r';
631 named_section_real (rname, SECTION_LINKONCE, decl);
632 return;
634 /* For .text.foo we want to use .rodata.foo. */
635 else if (flag_function_sections && flag_data_sections
636 && strncmp (name, ".text.", 6) == 0)
638 size_t len = strlen (name) + 1;
639 char *rname = alloca (len + 2);
641 memcpy (rname, ".rodata", 7);
642 memcpy (rname + 7, name + 5, len - 5);
643 named_section_flags (rname, 0);
644 return;
648 readonly_data_section ();
651 /* Switch to read-only data section associated with function DECL
652 for targets where that section should be always the single
653 readonly data section. */
655 void
656 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
658 readonly_data_section ();
661 /* Switch to section for variable DECL. RELOC is the same as the
662 argument to SELECT_SECTION. */
664 void
665 variable_section (tree decl, int reloc)
667 if (IN_NAMED_SECTION (decl))
668 named_section (decl, NULL, reloc);
669 else
670 targetm.asm_out.select_section (decl, reloc, DECL_ALIGN (decl));
673 /* Tell assembler to switch to the section for string merging. */
675 void
676 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
677 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
678 unsigned int flags ATTRIBUTE_UNUSED)
680 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
681 && TREE_CODE (decl) == STRING_CST
682 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
683 && align <= 256
684 && TREE_STRING_LENGTH (decl) >= int_size_in_bytes (TREE_TYPE (decl)))
686 enum machine_mode mode;
687 unsigned int modesize;
688 const char *str;
689 int i, j, len, unit;
690 char name[30];
692 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
693 modesize = GET_MODE_BITSIZE (mode);
694 if (modesize >= 8 && modesize <= 256
695 && (modesize & (modesize - 1)) == 0)
697 if (align < modesize)
698 align = modesize;
700 str = TREE_STRING_POINTER (decl);
701 len = TREE_STRING_LENGTH (decl);
702 unit = GET_MODE_SIZE (mode);
704 /* Check for embedded NUL characters. */
705 for (i = 0; i < len; i += unit)
707 for (j = 0; j < unit; j++)
708 if (str[i + j] != '\0')
709 break;
710 if (j == unit)
711 break;
713 if (i == len - unit)
715 sprintf (name, ".rodata.str%d.%d", modesize / 8,
716 (int) (align / 8));
717 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
718 if (!i && modesize < align)
720 /* A "" string with requested alignment greater than
721 character size might cause a problem:
722 if some other string required even bigger
723 alignment than "", then linker might think the
724 "" is just part of padding after some other string
725 and not put it into the hash table initially.
726 But this means "" could have smaller alignment
727 than requested. */
728 #ifdef ASM_OUTPUT_SECTION_START
729 named_section_flags (name, flags);
730 ASM_OUTPUT_SECTION_START (asm_out_file);
731 #else
732 readonly_data_section ();
733 #endif
734 return;
737 named_section_flags (name, flags);
738 return;
743 readonly_data_section ();
746 /* Tell assembler to switch to the section for constant merging. */
748 void
749 mergeable_constant_section (enum machine_mode mode ATTRIBUTE_UNUSED,
750 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
751 unsigned int flags ATTRIBUTE_UNUSED)
753 unsigned int modesize = GET_MODE_BITSIZE (mode);
755 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
756 && mode != VOIDmode
757 && mode != BLKmode
758 && modesize <= align
759 && align >= 8
760 && align <= 256
761 && (align & (align - 1)) == 0)
763 char name[24];
765 sprintf (name, ".rodata.cst%d", (int) (align / 8));
766 flags |= (align / 8) | SECTION_MERGE;
767 named_section_flags (name, flags);
768 return;
771 readonly_data_section ();
774 /* Given NAME, a putative register name, discard any customary prefixes. */
776 static const char *
777 strip_reg_name (const char *name)
779 #ifdef REGISTER_PREFIX
780 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
781 name += strlen (REGISTER_PREFIX);
782 #endif
783 if (name[0] == '%' || name[0] == '#')
784 name++;
785 return name;
788 /* The user has asked for a DECL to have a particular name. Set (or
789 change) it in such a way that we don't prefix an underscore to
790 it. */
791 void
792 set_user_assembler_name (tree decl, const char *name)
794 char *starred = alloca (strlen (name) + 2);
795 starred[0] = '*';
796 strcpy (starred + 1, name);
797 change_decl_assembler_name (decl, get_identifier (starred));
798 SET_DECL_RTL (decl, NULL_RTX);
801 /* Decode an `asm' spec for a declaration as a register name.
802 Return the register number, or -1 if nothing specified,
803 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
804 or -3 if ASMSPEC is `cc' and is not recognized,
805 or -4 if ASMSPEC is `memory' and is not recognized.
806 Accept an exact spelling or a decimal number.
807 Prefixes such as % are optional. */
810 decode_reg_name (const char *asmspec)
812 if (asmspec != 0)
814 int i;
816 /* Get rid of confusing prefixes. */
817 asmspec = strip_reg_name (asmspec);
819 /* Allow a decimal number as a "register name". */
820 for (i = strlen (asmspec) - 1; i >= 0; i--)
821 if (! ISDIGIT (asmspec[i]))
822 break;
823 if (asmspec[0] != 0 && i < 0)
825 i = atoi (asmspec);
826 if (i < FIRST_PSEUDO_REGISTER && i >= 0)
827 return i;
828 else
829 return -2;
832 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
833 if (reg_names[i][0]
834 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
835 return i;
837 #ifdef ADDITIONAL_REGISTER_NAMES
839 static const struct { const char *const name; const int number; } table[]
840 = ADDITIONAL_REGISTER_NAMES;
842 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
843 if (! strcmp (asmspec, table[i].name))
844 return table[i].number;
846 #endif /* ADDITIONAL_REGISTER_NAMES */
848 if (!strcmp (asmspec, "memory"))
849 return -4;
851 if (!strcmp (asmspec, "cc"))
852 return -3;
854 return -2;
857 return -1;
860 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
861 have static storage duration. In other words, it should not be an
862 automatic variable, including PARM_DECLs.
864 There is, however, one exception: this function handles variables
865 explicitly placed in a particular register by the user.
867 This is never called for PARM_DECL nodes. */
869 void
870 make_decl_rtl (tree decl)
872 const char *name = 0;
873 int reg_number;
874 rtx x;
876 /* Check that we are not being given an automatic variable. */
877 gcc_assert (TREE_CODE (decl) != PARM_DECL
878 && TREE_CODE (decl) != RESULT_DECL);
880 /* A weak alias has TREE_PUBLIC set but not the other bits. */
881 gcc_assert (TREE_CODE (decl) != VAR_DECL
882 || TREE_STATIC (decl)
883 || TREE_PUBLIC (decl)
884 || DECL_EXTERNAL (decl)
885 || DECL_REGISTER (decl));
887 /* And that we were not given a type or a label. */
888 gcc_assert (TREE_CODE (decl) != TYPE_DECL
889 && TREE_CODE (decl) != LABEL_DECL);
891 /* For a duplicate declaration, we can be called twice on the
892 same DECL node. Don't discard the RTL already made. */
893 if (DECL_RTL_SET_P (decl))
895 /* If the old RTL had the wrong mode, fix the mode. */
896 if (GET_MODE (DECL_RTL (decl)) != DECL_MODE (decl))
897 SET_DECL_RTL (decl, adjust_address_nv (DECL_RTL (decl),
898 DECL_MODE (decl), 0));
900 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
901 return;
903 /* ??? Another way to do this would be to maintain a hashed
904 table of such critters. Instead of adding stuff to a DECL
905 to give certain attributes to it, we could use an external
906 hash map from DECL to set of attributes. */
908 /* Let the target reassign the RTL if it wants.
909 This is necessary, for example, when one machine specific
910 decl attribute overrides another. */
911 targetm.encode_section_info (decl, DECL_RTL (decl), false);
913 /* Make this function static known to the mudflap runtime. */
914 if (flag_mudflap && TREE_CODE (decl) == VAR_DECL)
915 mudflap_enqueue_decl (decl);
917 return;
920 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
922 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
924 reg_number = decode_reg_name (name);
925 /* First detect errors in declaring global registers. */
926 if (reg_number == -1)
927 error ("%Jregister name not specified for %qD", decl, decl);
928 else if (reg_number < 0)
929 error ("%Jinvalid register name for %qD", decl, decl);
930 else if (TYPE_MODE (TREE_TYPE (decl)) == BLKmode)
931 error ("%Jdata type of %qD isn%'t suitable for a register",
932 decl, decl);
933 else if (! HARD_REGNO_MODE_OK (reg_number, TYPE_MODE (TREE_TYPE (decl))))
934 error ("%Jregister specified for %qD isn%'t suitable for data type",
935 decl, decl);
936 /* Now handle properly declared static register variables. */
937 else
939 int nregs;
941 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
943 DECL_INITIAL (decl) = 0;
944 error ("global register variable has initial value");
946 if (TREE_THIS_VOLATILE (decl))
947 warning (0, "volatile register variables don%'t "
948 "work as you might wish");
950 /* If the user specified one of the eliminables registers here,
951 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
952 confused with that register and be eliminated. This usage is
953 somewhat suspect... */
955 SET_DECL_RTL (decl, gen_rtx_raw_REG (DECL_MODE (decl), reg_number));
956 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
957 REG_USERVAR_P (DECL_RTL (decl)) = 1;
959 if (TREE_STATIC (decl))
961 /* Make this register global, so not usable for anything
962 else. */
963 #ifdef ASM_DECLARE_REGISTER_GLOBAL
964 name = IDENTIFIER_POINTER (DECL_NAME (decl));
965 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
966 #endif
967 nregs = hard_regno_nregs[reg_number][DECL_MODE (decl)];
968 while (nregs > 0)
969 globalize_reg (reg_number + --nregs);
972 /* As a register variable, it has no section. */
973 return;
976 /* Now handle ordinary static variables and functions (in memory).
977 Also handle vars declared register invalidly. */
978 else if (name[0] == '*')
980 #ifdef REGISTER_PREFIX
981 if (strlen (REGISTER_PREFIX) != 0)
983 reg_number = decode_reg_name (name);
984 if (reg_number >= 0 || reg_number == -3)
985 error ("%Jregister name given for non-register variable %qD", decl, decl);
987 #endif
990 /* Specifying a section attribute on a variable forces it into a
991 non-.bss section, and thus it cannot be common. */
992 if (TREE_CODE (decl) == VAR_DECL
993 && DECL_SECTION_NAME (decl) != NULL_TREE
994 && DECL_INITIAL (decl) == NULL_TREE
995 && DECL_COMMON (decl))
996 DECL_COMMON (decl) = 0;
998 /* Variables can't be both common and weak. */
999 if (TREE_CODE (decl) == VAR_DECL && DECL_WEAK (decl))
1000 DECL_COMMON (decl) = 0;
1002 x = gen_rtx_SYMBOL_REF (Pmode, name);
1003 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
1004 SYMBOL_REF_DECL (x) = decl;
1006 x = gen_rtx_MEM (DECL_MODE (decl), x);
1007 if (TREE_CODE (decl) != FUNCTION_DECL)
1008 set_mem_attributes (x, decl, 1);
1009 SET_DECL_RTL (decl, x);
1011 /* Optionally set flags or add text to the name to record information
1012 such as that it is a function name.
1013 If the name is changed, the macro ASM_OUTPUT_LABELREF
1014 will have to know how to strip this information. */
1015 targetm.encode_section_info (decl, DECL_RTL (decl), true);
1017 /* Make this function static known to the mudflap runtime. */
1018 if (flag_mudflap && TREE_CODE (decl) == VAR_DECL)
1019 mudflap_enqueue_decl (decl);
1022 /* Make the rtl for variable VAR be volatile.
1023 Use this only for static variables. */
1025 void
1026 make_var_volatile (tree var)
1028 gcc_assert (MEM_P (DECL_RTL (var)));
1030 MEM_VOLATILE_P (DECL_RTL (var)) = 1;
1033 /* Output a string of literal assembler code
1034 for an `asm' keyword used between functions. */
1036 void
1037 assemble_asm (tree string)
1039 app_enable ();
1041 if (TREE_CODE (string) == ADDR_EXPR)
1042 string = TREE_OPERAND (string, 0);
1044 fprintf (asm_out_file, "\t%s\n", TREE_STRING_POINTER (string));
1047 /* Record an element in the table of global destructors. SYMBOL is
1048 a SYMBOL_REF of the function to be called; PRIORITY is a number
1049 between 0 and MAX_INIT_PRIORITY. */
1051 void
1052 default_stabs_asm_out_destructor (rtx symbol ATTRIBUTE_UNUSED,
1053 int priority ATTRIBUTE_UNUSED)
1055 #if defined DBX_DEBUGGING_INFO || defined XCOFF_DEBUGGING_INFO
1056 /* Tell GNU LD that this is part of the static destructor set.
1057 This will work for any system that uses stabs, most usefully
1058 aout systems. */
1059 dbxout_begin_simple_stabs ("___DTOR_LIST__", 22 /* N_SETT */);
1060 dbxout_stab_value_label (XSTR (symbol, 0));
1061 #else
1062 sorry ("global destructors not supported on this target");
1063 #endif
1066 void
1067 default_named_section_asm_out_destructor (rtx symbol, int priority)
1069 const char *section = ".dtors";
1070 char buf[16];
1072 /* ??? This only works reliably with the GNU linker. */
1073 if (priority != DEFAULT_INIT_PRIORITY)
1075 sprintf (buf, ".dtors.%.5u",
1076 /* Invert the numbering so the linker puts us in the proper
1077 order; constructors are run from right to left, and the
1078 linker sorts in increasing order. */
1079 MAX_INIT_PRIORITY - priority);
1080 section = buf;
1083 named_section_flags (section, SECTION_WRITE);
1084 assemble_align (POINTER_SIZE);
1085 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1088 #ifdef DTORS_SECTION_ASM_OP
1089 void
1090 dtors_section (void)
1092 if (in_section != in_dtors)
1094 in_section = in_dtors;
1095 fputs (DTORS_SECTION_ASM_OP, asm_out_file);
1096 fputc ('\n', asm_out_file);
1100 void
1101 default_dtor_section_asm_out_destructor (rtx symbol,
1102 int priority ATTRIBUTE_UNUSED)
1104 dtors_section ();
1105 assemble_align (POINTER_SIZE);
1106 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1108 #endif
1110 /* Likewise for global constructors. */
1112 void
1113 default_stabs_asm_out_constructor (rtx symbol ATTRIBUTE_UNUSED,
1114 int priority ATTRIBUTE_UNUSED)
1116 #if defined DBX_DEBUGGING_INFO || defined XCOFF_DEBUGGING_INFO
1117 /* Tell GNU LD that this is part of the static destructor set.
1118 This will work for any system that uses stabs, most usefully
1119 aout systems. */
1120 dbxout_begin_simple_stabs ("___CTOR_LIST__", 22 /* N_SETT */);
1121 dbxout_stab_value_label (XSTR (symbol, 0));
1122 #else
1123 sorry ("global constructors not supported on this target");
1124 #endif
1127 void
1128 default_named_section_asm_out_constructor (rtx symbol, int priority)
1130 const char *section = ".ctors";
1131 char buf[16];
1133 /* ??? This only works reliably with the GNU linker. */
1134 if (priority != DEFAULT_INIT_PRIORITY)
1136 sprintf (buf, ".ctors.%.5u",
1137 /* Invert the numbering so the linker puts us in the proper
1138 order; constructors are run from right to left, and the
1139 linker sorts in increasing order. */
1140 MAX_INIT_PRIORITY - priority);
1141 section = buf;
1144 named_section_flags (section, SECTION_WRITE);
1145 assemble_align (POINTER_SIZE);
1146 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1149 #ifdef CTORS_SECTION_ASM_OP
1150 void
1151 ctors_section (void)
1153 if (in_section != in_ctors)
1155 in_section = in_ctors;
1156 fputs (CTORS_SECTION_ASM_OP, asm_out_file);
1157 fputc ('\n', asm_out_file);
1161 void
1162 default_ctor_section_asm_out_constructor (rtx symbol,
1163 int priority ATTRIBUTE_UNUSED)
1165 ctors_section ();
1166 assemble_align (POINTER_SIZE);
1167 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1169 #endif
1171 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1172 a nonzero value if the constant pool should be output before the
1173 start of the function, or a zero value if the pool should output
1174 after the end of the function. The default is to put it before the
1175 start. */
1177 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1178 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1179 #endif
1181 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1182 to be output to assembler.
1183 Set first_global_object_name and weak_global_object_name as appropriate. */
1185 void
1186 notice_global_symbol (tree decl)
1188 const char **type = &first_global_object_name;
1190 if (first_global_object_name
1191 || !TREE_PUBLIC (decl) || DECL_EXTERNAL (decl)
1192 || !DECL_NAME (decl)
1193 || (TREE_CODE (decl) != FUNCTION_DECL
1194 && (TREE_CODE (decl) != VAR_DECL
1195 || (DECL_COMMON (decl)
1196 && (DECL_INITIAL (decl) == 0
1197 || DECL_INITIAL (decl) == error_mark_node))))
1198 || !MEM_P (DECL_RTL (decl)))
1199 return;
1201 /* We win when global object is found, but it is useful to know about weak
1202 symbol as well so we can produce nicer unique names. */
1203 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl))
1204 type = &weak_global_object_name;
1206 if (!*type)
1208 const char *p;
1209 char *name;
1210 rtx decl_rtl = DECL_RTL (decl);
1212 p = targetm.strip_name_encoding (XSTR (XEXP (decl_rtl, 0), 0));
1213 name = xstrdup (p);
1215 *type = name;
1219 /* Output assembler code for the constant pool of a function and associated
1220 with defining the name of the function. DECL describes the function.
1221 NAME is the function's name. For the constant pool, we use the current
1222 constant pool data. */
1224 void
1225 assemble_start_function (tree decl, const char *fnname)
1227 int align;
1228 char tmp_label[100];
1229 bool hot_label_written = false;
1231 cfun->unlikely_text_section_name = NULL;
1233 first_function_block_is_cold = false;
1234 if (flag_reorder_blocks_and_partition)
1236 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "HOTB", const_labelno);
1237 cfun->hot_section_label = ggc_strdup (tmp_label);
1238 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "COLDB", const_labelno);
1239 cfun->cold_section_label = ggc_strdup (tmp_label);
1240 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "HOTE", const_labelno);
1241 cfun->hot_section_end_label = ggc_strdup (tmp_label);
1242 ASM_GENERATE_INTERNAL_LABEL (tmp_label, "COLDE", const_labelno);
1243 cfun->cold_section_end_label = ggc_strdup (tmp_label);
1244 const_labelno++;
1246 else
1248 cfun->hot_section_label = NULL;
1249 cfun->cold_section_label = NULL;
1250 cfun->hot_section_end_label = NULL;
1251 cfun->cold_section_end_label = NULL;
1254 /* The following code does not need preprocessing in the assembler. */
1256 app_disable ();
1258 if (CONSTANT_POOL_BEFORE_FUNCTION)
1259 output_constant_pool (fnname, decl);
1261 resolve_unique_section (decl, 0, flag_function_sections);
1263 /* Make sure the not and cold text (code) sections are properly
1264 aligned. This is necessary here in the case where the function
1265 has both hot and cold sections, because we don't want to re-set
1266 the alignment when the section switch happens mid-function. */
1268 if (flag_reorder_blocks_and_partition)
1270 unlikely_text_section ();
1271 assemble_align (FUNCTION_BOUNDARY);
1272 ASM_OUTPUT_LABEL (asm_out_file, cfun->cold_section_label);
1273 if (BB_PARTITION (ENTRY_BLOCK_PTR->next_bb) == BB_COLD_PARTITION)
1275 /* Since the function starts with a cold section, we need to
1276 explicitly align the hot section and write out the hot
1277 section label. */
1278 text_section ();
1279 assemble_align (FUNCTION_BOUNDARY);
1280 ASM_OUTPUT_LABEL (asm_out_file, cfun->hot_section_label);
1281 hot_label_written = true;
1282 first_function_block_is_cold = true;
1285 else if (DECL_SECTION_NAME (decl))
1287 /* Calls to function_section rely on first_function_block_is_cold
1288 being accurate. The first block may be cold even if we aren't
1289 doing partitioning, if the entire function was decided by
1290 choose_function_section (predict.c) to be cold. */
1292 int i;
1293 int len;
1294 char *s;
1296 initialize_cold_section_name ();
1298 /* The following is necessary, because 'strcmp
1299 (TREE_STRING_POINTER (DECL_SECTION_NAME (decl)), blah)' always
1300 fails, presumably because TREE_STRING_POINTER is declared to
1301 be an array of size 1 of char. */
1303 len = TREE_STRING_LENGTH (DECL_SECTION_NAME (decl));
1304 s = (char *) xmalloc (len + 1);
1306 for (i = 0; i < len; i ++)
1307 s[i] = (TREE_STRING_POINTER (DECL_SECTION_NAME (decl)))[i];
1308 s[len] = '\0';
1310 if (cfun->unlikely_text_section_name
1311 && (strcmp (s, cfun->unlikely_text_section_name) == 0))
1312 first_function_block_is_cold = true;
1315 last_text_section = no_section;
1317 /* Switch to the correct text section for the start of the function. */
1319 function_section (decl);
1320 if (flag_reorder_blocks_and_partition
1321 && !hot_label_written)
1322 ASM_OUTPUT_LABEL (asm_out_file, cfun->hot_section_label);
1324 /* Tell assembler to move to target machine's alignment for functions. */
1325 align = floor_log2 (FUNCTION_BOUNDARY / BITS_PER_UNIT);
1326 if (align < force_align_functions_log)
1327 align = force_align_functions_log;
1328 if (align > 0)
1330 ASM_OUTPUT_ALIGN (asm_out_file, align);
1333 /* Handle a user-specified function alignment.
1334 Note that we still need to align to FUNCTION_BOUNDARY, as above,
1335 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1336 if (align_functions_log > align
1337 && cfun->function_frequency != FUNCTION_FREQUENCY_UNLIKELY_EXECUTED)
1339 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1340 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1341 align_functions_log, align_functions - 1);
1342 #else
1343 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1344 #endif
1347 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1348 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1349 #endif
1351 (*debug_hooks->begin_function) (decl);
1353 /* Make function name accessible from other files, if appropriate. */
1355 if (TREE_PUBLIC (decl))
1357 notice_global_symbol (decl);
1359 globalize_decl (decl);
1361 maybe_assemble_visibility (decl);
1364 if (DECL_PRESERVE_P (decl))
1365 targetm.asm_out.mark_decl_preserved (fnname);
1367 /* Do any machine/system dependent processing of the function name. */
1368 #ifdef ASM_DECLARE_FUNCTION_NAME
1369 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1370 #else
1371 /* Standard thing is just output label for the function. */
1372 ASM_OUTPUT_LABEL (asm_out_file, fnname);
1373 #endif /* ASM_DECLARE_FUNCTION_NAME */
1375 insert_section_boundary_note ();
1378 /* Output assembler code associated with defining the size of the
1379 function. DECL describes the function. NAME is the function's name. */
1381 void
1382 assemble_end_function (tree decl, const char *fnname)
1384 #ifdef ASM_DECLARE_FUNCTION_SIZE
1385 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1386 #endif
1387 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1389 output_constant_pool (fnname, decl);
1390 function_section (decl); /* need to switch back */
1392 /* Output labels for end of hot/cold text sections (to be used by
1393 debug info.) */
1394 if (flag_reorder_blocks_and_partition)
1396 enum in_section save_text_section;
1398 save_text_section = in_section;
1399 unlikely_text_section ();
1400 ASM_OUTPUT_LABEL (asm_out_file, cfun->cold_section_end_label);
1401 if (first_function_block_is_cold)
1402 text_section ();
1403 else
1404 function_section (decl);
1405 ASM_OUTPUT_LABEL (asm_out_file, cfun->hot_section_end_label);
1406 if (save_text_section == in_unlikely_executed_text)
1407 unlikely_text_section ();
1411 /* Assemble code to leave SIZE bytes of zeros. */
1413 void
1414 assemble_zeros (unsigned HOST_WIDE_INT size)
1416 /* Do no output if -fsyntax-only. */
1417 if (flag_syntax_only)
1418 return;
1420 #ifdef ASM_NO_SKIP_IN_TEXT
1421 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1422 so we must output 0s explicitly in the text section. */
1423 if ((ASM_NO_SKIP_IN_TEXT && in_text_section ())
1424 || (ASM_NO_SKIP_IN_TEXT && in_unlikely_text_section ()))
1426 unsigned HOST_WIDE_INT i;
1427 for (i = 0; i < size; i++)
1428 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1430 else
1431 #endif
1432 if (size > 0)
1433 ASM_OUTPUT_SKIP (asm_out_file, size);
1436 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1438 void
1439 assemble_align (int align)
1441 if (align > BITS_PER_UNIT)
1443 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1447 /* Assemble a string constant with the specified C string as contents. */
1449 void
1450 assemble_string (const char *p, int size)
1452 int pos = 0;
1453 int maximum = 2000;
1455 /* If the string is very long, split it up. */
1457 while (pos < size)
1459 int thissize = size - pos;
1460 if (thissize > maximum)
1461 thissize = maximum;
1463 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1465 pos += thissize;
1466 p += thissize;
1471 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1472 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1473 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1474 #else
1475 #if defined ASM_OUTPUT_ALIGNED_LOCAL
1476 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1477 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, DECL_ALIGN (decl))
1478 #else
1479 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1480 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded)
1481 #endif
1482 #endif
1484 #if defined ASM_OUTPUT_ALIGNED_BSS
1485 #define ASM_EMIT_BSS(decl, name, size, rounded) \
1486 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1487 #else
1488 #if defined ASM_OUTPUT_BSS
1489 #define ASM_EMIT_BSS(decl, name, size, rounded) \
1490 ASM_OUTPUT_BSS (asm_out_file, decl, name, size, rounded)
1491 #else
1492 #undef ASM_EMIT_BSS
1493 #endif
1494 #endif
1496 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1497 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1498 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1499 #else
1500 #if defined ASM_OUTPUT_ALIGNED_COMMON
1501 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1502 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size, DECL_ALIGN (decl))
1503 #else
1504 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1505 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded)
1506 #endif
1507 #endif
1509 static bool
1510 asm_emit_uninitialised (tree decl, const char *name,
1511 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1512 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1514 enum
1516 asm_dest_common,
1517 asm_dest_bss,
1518 asm_dest_local
1520 destination = asm_dest_local;
1522 /* ??? We should handle .bss via select_section mechanisms rather than
1523 via special target hooks. That would eliminate this special case. */
1524 if (TREE_PUBLIC (decl))
1526 if (!DECL_COMMON (decl))
1527 #ifdef ASM_EMIT_BSS
1528 destination = asm_dest_bss;
1529 #else
1530 return false;
1531 #endif
1532 else
1533 destination = asm_dest_common;
1536 if (destination != asm_dest_common)
1538 resolve_unique_section (decl, 0, flag_data_sections);
1539 /* Custom sections don't belong here. */
1540 if (DECL_SECTION_NAME (decl))
1541 return false;
1544 if (destination == asm_dest_bss)
1545 globalize_decl (decl);
1547 if (flag_shared_data)
1549 switch (destination)
1551 #ifdef ASM_OUTPUT_SHARED_BSS
1552 case asm_dest_bss:
1553 ASM_OUTPUT_SHARED_BSS (asm_out_file, decl, name, size, rounded);
1554 return;
1555 #endif
1556 #ifdef ASM_OUTPUT_SHARED_COMMON
1557 case asm_dest_common:
1558 ASM_OUTPUT_SHARED_COMMON (asm_out_file, name, size, rounded);
1559 return;
1560 #endif
1561 #ifdef ASM_OUTPUT_SHARED_LOCAL
1562 case asm_dest_local:
1563 ASM_OUTPUT_SHARED_LOCAL (asm_out_file, name, size, rounded);
1564 return;
1565 #endif
1566 default:
1567 break;
1571 switch (destination)
1573 #ifdef ASM_EMIT_BSS
1574 case asm_dest_bss:
1575 ASM_EMIT_BSS (decl, name, size, rounded);
1576 break;
1577 #endif
1578 case asm_dest_common:
1579 ASM_EMIT_COMMON (decl, name, size, rounded);
1580 break;
1581 case asm_dest_local:
1582 ASM_EMIT_LOCAL (decl, name, size, rounded);
1583 break;
1584 default:
1585 gcc_unreachable ();
1588 return true;
1591 /* Assemble everything that is needed for a variable or function declaration.
1592 Not used for automatic variables, and not used for function definitions.
1593 Should not be called for variables of incomplete structure type.
1595 TOP_LEVEL is nonzero if this variable has file scope.
1596 AT_END is nonzero if this is the special handling, at end of compilation,
1597 to define things that have had only tentative definitions.
1598 DONT_OUTPUT_DATA if nonzero means don't actually output the
1599 initial value (that will be done by the caller). */
1601 void
1602 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
1603 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
1605 const char *name;
1606 unsigned int align;
1607 int reloc = 0;
1608 rtx decl_rtl;
1610 if (lang_hooks.decls.prepare_assemble_variable)
1611 lang_hooks.decls.prepare_assemble_variable (decl);
1613 last_assemble_variable_decl = 0;
1615 /* Normally no need to say anything here for external references,
1616 since assemble_external is called by the language-specific code
1617 when a declaration is first seen. */
1619 if (DECL_EXTERNAL (decl))
1620 return;
1622 /* Output no assembler code for a function declaration.
1623 Only definitions of functions output anything. */
1625 if (TREE_CODE (decl) == FUNCTION_DECL)
1626 return;
1628 /* Do nothing for global register variables. */
1629 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
1631 TREE_ASM_WRITTEN (decl) = 1;
1632 return;
1635 /* If type was incomplete when the variable was declared,
1636 see if it is complete now. */
1638 if (DECL_SIZE (decl) == 0)
1639 layout_decl (decl, 0);
1641 /* Still incomplete => don't allocate it; treat the tentative defn
1642 (which is what it must have been) as an `extern' reference. */
1644 if (!dont_output_data && DECL_SIZE (decl) == 0)
1646 error ("%Jstorage size of %qD isn%'t known", decl, decl);
1647 TREE_ASM_WRITTEN (decl) = 1;
1648 return;
1651 /* The first declaration of a variable that comes through this function
1652 decides whether it is global (in C, has external linkage)
1653 or local (in C, has internal linkage). So do nothing more
1654 if this function has already run. */
1656 if (TREE_ASM_WRITTEN (decl))
1657 return;
1659 /* Make sure targetm.encode_section_info is invoked before we set
1660 ASM_WRITTEN. */
1661 decl_rtl = DECL_RTL (decl);
1663 TREE_ASM_WRITTEN (decl) = 1;
1665 /* Do no output if -fsyntax-only. */
1666 if (flag_syntax_only)
1667 return;
1669 app_disable ();
1671 if (! dont_output_data
1672 && ! host_integerp (DECL_SIZE_UNIT (decl), 1))
1674 error ("%Jsize of variable %qD is too large", decl, decl);
1675 return;
1678 name = XSTR (XEXP (decl_rtl, 0), 0);
1679 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
1680 notice_global_symbol (decl);
1682 /* Compute the alignment of this data. */
1684 align = DECL_ALIGN (decl);
1686 /* In the case for initialing an array whose length isn't specified,
1687 where we have not yet been able to do the layout,
1688 figure out the proper alignment now. */
1689 if (dont_output_data && DECL_SIZE (decl) == 0
1690 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
1691 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
1693 /* Some object file formats have a maximum alignment which they support.
1694 In particular, a.out format supports a maximum alignment of 4. */
1695 if (align > MAX_OFILE_ALIGNMENT)
1697 warning (0, "%Jalignment of %qD is greater than maximum object "
1698 "file alignment. Using %d", decl, decl,
1699 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
1700 align = MAX_OFILE_ALIGNMENT;
1703 /* On some machines, it is good to increase alignment sometimes. */
1704 if (! DECL_USER_ALIGN (decl))
1706 #ifdef DATA_ALIGNMENT
1707 align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1708 #endif
1709 #ifdef CONSTANT_ALIGNMENT
1710 if (DECL_INITIAL (decl) != 0 && DECL_INITIAL (decl) != error_mark_node)
1711 align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
1712 #endif
1715 /* Reset the alignment in case we have made it tighter, so we can benefit
1716 from it in get_pointer_alignment. */
1717 DECL_ALIGN (decl) = align;
1718 set_mem_align (decl_rtl, align);
1720 if (TREE_PUBLIC (decl))
1721 maybe_assemble_visibility (decl);
1723 if (DECL_PRESERVE_P (decl))
1724 targetm.asm_out.mark_decl_preserved (name);
1726 /* Handle uninitialized definitions. */
1728 /* If the decl has been given an explicit section name, then it
1729 isn't common, and shouldn't be handled as such. */
1730 if (DECL_SECTION_NAME (decl) || dont_output_data)
1732 /* We don't implement common thread-local data at present. */
1733 else if (DECL_THREAD_LOCAL (decl))
1735 if (DECL_COMMON (decl))
1736 sorry ("thread-local COMMON data not implemented");
1738 else if (DECL_INITIAL (decl) == 0
1739 || DECL_INITIAL (decl) == error_mark_node
1740 || (flag_zero_initialized_in_bss
1741 /* Leave constant zeroes in .rodata so they can be shared. */
1742 && !TREE_READONLY (decl)
1743 && initializer_zerop (DECL_INITIAL (decl))))
1745 unsigned HOST_WIDE_INT size = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
1746 unsigned HOST_WIDE_INT rounded = size;
1748 /* Don't allocate zero bytes of common,
1749 since that means "undefined external" in the linker. */
1750 if (size == 0)
1751 rounded = 1;
1753 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1754 so that each uninitialized object starts on such a boundary. */
1755 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
1756 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1757 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1759 #if !defined(ASM_OUTPUT_ALIGNED_COMMON) && !defined(ASM_OUTPUT_ALIGNED_DECL_COMMON) && !defined(ASM_OUTPUT_ALIGNED_BSS)
1760 if ((unsigned HOST_WIDE_INT) DECL_ALIGN_UNIT (decl) > rounded)
1761 warning (0, "%Jrequested alignment for %qD is greater than "
1762 "implemented alignment of %d", decl, decl, rounded);
1763 #endif
1765 /* If the target cannot output uninitialized but not common global data
1766 in .bss, then we have to use .data, so fall through. */
1767 if (asm_emit_uninitialised (decl, name, size, rounded))
1768 return;
1771 /* Handle initialized definitions.
1772 Also handle uninitialized global definitions if -fno-common and the
1773 target doesn't support ASM_OUTPUT_BSS. */
1775 /* First make the assembler name(s) global if appropriate. */
1776 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
1777 globalize_decl (decl);
1779 /* Output any data that we will need to use the address of. */
1780 if (DECL_INITIAL (decl) == error_mark_node)
1781 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1782 else if (DECL_INITIAL (decl))
1784 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1785 output_addressed_constants (DECL_INITIAL (decl));
1788 /* Switch to the appropriate section. */
1789 resolve_unique_section (decl, reloc, flag_data_sections);
1790 variable_section (decl, reloc);
1792 /* dbxout.c needs to know this. */
1793 if (in_text_section () || in_unlikely_text_section ())
1794 DECL_IN_TEXT_SECTION (decl) = 1;
1796 /* Output the alignment of this data. */
1797 if (align > BITS_PER_UNIT)
1798 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (DECL_ALIGN_UNIT (decl)));
1800 /* Do any machine/system dependent processing of the object. */
1801 #ifdef ASM_DECLARE_OBJECT_NAME
1802 last_assemble_variable_decl = decl;
1803 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
1804 #else
1805 /* Standard thing is just output label for the object. */
1806 ASM_OUTPUT_LABEL (asm_out_file, name);
1807 #endif /* ASM_DECLARE_OBJECT_NAME */
1809 if (!dont_output_data)
1811 if (DECL_INITIAL (decl)
1812 && DECL_INITIAL (decl) != error_mark_node
1813 && !initializer_zerop (DECL_INITIAL (decl)))
1814 /* Output the actual data. */
1815 output_constant (DECL_INITIAL (decl),
1816 tree_low_cst (DECL_SIZE_UNIT (decl), 1),
1817 align);
1818 else
1819 /* Leave space for it. */
1820 assemble_zeros (tree_low_cst (DECL_SIZE_UNIT (decl), 1));
1824 /* Return 1 if type TYPE contains any pointers. */
1826 static int
1827 contains_pointers_p (tree type)
1829 switch (TREE_CODE (type))
1831 case POINTER_TYPE:
1832 case REFERENCE_TYPE:
1833 /* I'm not sure whether OFFSET_TYPE needs this treatment,
1834 so I'll play safe and return 1. */
1835 case OFFSET_TYPE:
1836 return 1;
1838 case RECORD_TYPE:
1839 case UNION_TYPE:
1840 case QUAL_UNION_TYPE:
1842 tree fields;
1843 /* For a type that has fields, see if the fields have pointers. */
1844 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
1845 if (TREE_CODE (fields) == FIELD_DECL
1846 && contains_pointers_p (TREE_TYPE (fields)))
1847 return 1;
1848 return 0;
1851 case ARRAY_TYPE:
1852 /* An array type contains pointers if its element type does. */
1853 return contains_pointers_p (TREE_TYPE (type));
1855 default:
1856 return 0;
1860 /* In unit-at-a-time mode, we delay assemble_external processing until
1861 the compilation unit is finalized. This is the best we can do for
1862 right now (i.e. stage 3 of GCC 4.0) - the right thing is to delay
1863 it all the way to final. See PR 17982 for further discussion. */
1864 static GTY(()) tree pending_assemble_externals;
1866 #ifdef ASM_OUTPUT_EXTERNAL
1867 /* True if DECL is a function decl for which no out-of-line copy exists.
1868 It is assumed that DECL's assembler name has been set. */
1870 static bool
1871 incorporeal_function_p (tree decl)
1873 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
1875 const char *name;
1877 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
1878 && DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA)
1879 return true;
1881 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
1882 if (strncmp (name, "__builtin_", strlen ("__builtin_")) == 0)
1883 return true;
1885 return false;
1888 /* Actually do the tests to determine if this is necessary, and invoke
1889 ASM_OUTPUT_EXTERNAL. */
1890 static void
1891 assemble_external_real (tree decl)
1893 rtx rtl = DECL_RTL (decl);
1895 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
1896 && !SYMBOL_REF_USED (XEXP (rtl, 0))
1897 && !incorporeal_function_p (decl))
1899 /* Some systems do require some output. */
1900 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
1901 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
1904 #endif
1906 void
1907 process_pending_assemble_externals (void)
1909 #ifdef ASM_OUTPUT_EXTERNAL
1910 tree list;
1911 for (list = pending_assemble_externals; list; list = TREE_CHAIN (list))
1912 assemble_external_real (TREE_VALUE (list));
1914 pending_assemble_externals = 0;
1915 #endif
1918 /* Output something to declare an external symbol to the assembler.
1919 (Most assemblers don't need this, so we normally output nothing.)
1920 Do nothing if DECL is not external. */
1922 void
1923 assemble_external (tree decl ATTRIBUTE_UNUSED)
1925 /* Because most platforms do not define ASM_OUTPUT_EXTERNAL, the
1926 main body of this code is only rarely exercised. To provide some
1927 testing, on all platforms, we make sure that the ASM_OUT_FILE is
1928 open. If it's not, we should not be calling this function. */
1929 gcc_assert (asm_out_file);
1931 #ifdef ASM_OUTPUT_EXTERNAL
1932 if (!DECL_P (decl) || !DECL_EXTERNAL (decl) || !TREE_PUBLIC (decl))
1933 return;
1935 if (flag_unit_at_a_time)
1936 pending_assemble_externals = tree_cons (0, decl,
1937 pending_assemble_externals);
1938 else
1939 assemble_external_real (decl);
1940 #endif
1943 /* Similar, for calling a library function FUN. */
1945 void
1946 assemble_external_libcall (rtx fun)
1948 /* Declare library function name external when first used, if nec. */
1949 if (! SYMBOL_REF_USED (fun))
1951 SYMBOL_REF_USED (fun) = 1;
1952 targetm.asm_out.external_libcall (fun);
1956 /* Assemble a label named NAME. */
1958 void
1959 assemble_label (const char *name)
1961 ASM_OUTPUT_LABEL (asm_out_file, name);
1964 /* Set the symbol_referenced flag for ID. */
1965 void
1966 mark_referenced (tree id)
1968 TREE_SYMBOL_REFERENCED (id) = 1;
1971 /* Set the symbol_referenced flag for DECL and notify callgraph. */
1972 void
1973 mark_decl_referenced (tree decl)
1975 if (TREE_CODE (decl) == FUNCTION_DECL)
1977 /* Extern inline functions don't become needed when referenced.
1978 If we know a method will be emitted in other TU and no new
1979 functions can be marked reachable, just use the external
1980 definition. */
1981 struct cgraph_node *node = cgraph_node (decl);
1982 if (!DECL_EXTERNAL (decl)
1983 && (!node->local.vtable_method || !cgraph_global_info_ready
1984 || !node->local.finalized))
1985 cgraph_mark_needed_node (node);
1987 else if (TREE_CODE (decl) == VAR_DECL)
1989 struct cgraph_varpool_node *node = cgraph_varpool_node (decl);
1990 cgraph_varpool_mark_needed_node (node);
1991 /* C++ frontend use mark_decl_references to force COMDAT variables
1992 to be output that might appear dead otherwise. */
1993 node->force_output = true;
1995 /* else do nothing - we can get various sorts of CST nodes here,
1996 which do not need to be marked. */
1999 /* Output to FILE (an assembly file) a reference to NAME. If NAME
2000 starts with a *, the rest of NAME is output verbatim. Otherwise
2001 NAME is transformed in a target-specific way (usually by the
2002 addition of an underscore). */
2004 void
2005 assemble_name_raw (FILE *file, const char *name)
2007 if (name[0] == '*')
2008 fputs (&name[1], file);
2009 else
2010 ASM_OUTPUT_LABELREF (file, name);
2013 /* Like assemble_name_raw, but should be used when NAME might refer to
2014 an entity that is also represented as a tree (like a function or
2015 variable). If NAME does refer to such an entity, that entity will
2016 be marked as referenced. */
2018 void
2019 assemble_name (FILE *file, const char *name)
2021 const char *real_name;
2022 tree id;
2024 real_name = targetm.strip_name_encoding (name);
2026 id = maybe_get_identifier (real_name);
2027 if (id)
2028 mark_referenced (id);
2030 assemble_name_raw (file, name);
2033 /* Allocate SIZE bytes writable static space with a gensym name
2034 and return an RTX to refer to its address. */
2037 assemble_static_space (unsigned HOST_WIDE_INT size)
2039 char name[12];
2040 const char *namestring;
2041 rtx x;
2043 #if 0
2044 if (flag_shared_data)
2045 data_section ();
2046 #endif
2048 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
2049 ++const_labelno;
2050 namestring = ggc_strdup (name);
2052 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
2053 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
2055 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
2056 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
2057 BIGGEST_ALIGNMENT);
2058 #else
2059 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
2060 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
2061 #else
2063 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
2064 so that each uninitialized object starts on such a boundary. */
2065 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
2066 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
2067 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
2068 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2069 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
2070 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
2072 #endif
2073 #endif
2074 return x;
2077 /* Assemble the static constant template for function entry trampolines.
2078 This is done at most once per compilation.
2079 Returns an RTX for the address of the template. */
2081 static GTY(()) rtx initial_trampoline;
2083 #ifdef TRAMPOLINE_TEMPLATE
2085 assemble_trampoline_template (void)
2087 char label[256];
2088 const char *name;
2089 int align;
2090 rtx symbol;
2092 if (initial_trampoline)
2093 return initial_trampoline;
2095 /* By default, put trampoline templates in read-only data section. */
2097 #ifdef TRAMPOLINE_SECTION
2098 TRAMPOLINE_SECTION ();
2099 #else
2100 readonly_data_section ();
2101 #endif
2103 /* Write the assembler code to define one. */
2104 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
2105 if (align > 0)
2107 ASM_OUTPUT_ALIGN (asm_out_file, align);
2110 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
2111 TRAMPOLINE_TEMPLATE (asm_out_file);
2113 /* Record the rtl to refer to it. */
2114 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
2115 name = ggc_strdup (label);
2116 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
2117 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2119 initial_trampoline = gen_rtx_MEM (BLKmode, symbol);
2120 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
2122 return initial_trampoline;
2124 #endif
2126 /* A and B are either alignments or offsets. Return the minimum alignment
2127 that may be assumed after adding the two together. */
2129 static inline unsigned
2130 min_align (unsigned int a, unsigned int b)
2132 return (a | b) & -(a | b);
2135 /* Return the assembler directive for creating a given kind of integer
2136 object. SIZE is the number of bytes in the object and ALIGNED_P
2137 indicates whether it is known to be aligned. Return NULL if the
2138 assembly dialect has no such directive.
2140 The returned string should be printed at the start of a new line and
2141 be followed immediately by the object's initial value. */
2143 const char *
2144 integer_asm_op (int size, int aligned_p)
2146 struct asm_int_op *ops;
2148 if (aligned_p)
2149 ops = &targetm.asm_out.aligned_op;
2150 else
2151 ops = &targetm.asm_out.unaligned_op;
2153 switch (size)
2155 case 1:
2156 return targetm.asm_out.byte_op;
2157 case 2:
2158 return ops->hi;
2159 case 4:
2160 return ops->si;
2161 case 8:
2162 return ops->di;
2163 case 16:
2164 return ops->ti;
2165 default:
2166 return NULL;
2170 /* Use directive OP to assemble an integer object X. Print OP at the
2171 start of the line, followed immediately by the value of X. */
2173 void
2174 assemble_integer_with_op (const char *op, rtx x)
2176 fputs (op, asm_out_file);
2177 output_addr_const (asm_out_file, x);
2178 fputc ('\n', asm_out_file);
2181 /* The default implementation of the asm_out.integer target hook. */
2183 bool
2184 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2185 unsigned int size ATTRIBUTE_UNUSED,
2186 int aligned_p ATTRIBUTE_UNUSED)
2188 const char *op = integer_asm_op (size, aligned_p);
2189 /* Avoid GAS bugs for large values. Specifically negative values whose
2190 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2191 if (size > UNITS_PER_WORD && size > POINTER_SIZE / BITS_PER_UNIT)
2192 return false;
2193 return op && (assemble_integer_with_op (op, x), true);
2196 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2197 the alignment of the integer in bits. Return 1 if we were able to output
2198 the constant, otherwise 0. We must be able to output the constant,
2199 if FORCE is nonzero. */
2201 bool
2202 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2204 int aligned_p;
2206 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2208 /* See if the target hook can handle this kind of object. */
2209 if (targetm.asm_out.integer (x, size, aligned_p))
2210 return true;
2212 /* If the object is a multi-byte one, try splitting it up. Split
2213 it into words it if is multi-word, otherwise split it into bytes. */
2214 if (size > 1)
2216 enum machine_mode omode, imode;
2217 unsigned int subalign;
2218 unsigned int subsize, i;
2220 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2221 subalign = MIN (align, subsize * BITS_PER_UNIT);
2222 omode = mode_for_size (subsize * BITS_PER_UNIT, MODE_INT, 0);
2223 imode = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
2225 for (i = 0; i < size; i += subsize)
2227 rtx partial = simplify_subreg (omode, x, imode, i);
2228 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2229 break;
2231 if (i == size)
2232 return true;
2234 /* If we've printed some of it, but not all of it, there's no going
2235 back now. */
2236 gcc_assert (!i);
2239 gcc_assert (!force);
2241 return false;
2244 void
2245 assemble_real (REAL_VALUE_TYPE d, enum machine_mode mode, unsigned int align)
2247 long data[4];
2248 int i;
2249 int bitsize, nelts, nunits, units_per;
2251 /* This is hairy. We have a quantity of known size. real_to_target
2252 will put it into an array of *host* longs, 32 bits per element
2253 (even if long is more than 32 bits). We need to determine the
2254 number of array elements that are occupied (nelts) and the number
2255 of *target* min-addressable units that will be occupied in the
2256 object file (nunits). We cannot assume that 32 divides the
2257 mode's bitsize (size * BITS_PER_UNIT) evenly.
2259 size * BITS_PER_UNIT is used here to make sure that padding bits
2260 (which might appear at either end of the value; real_to_target
2261 will include the padding bits in its output array) are included. */
2263 nunits = GET_MODE_SIZE (mode);
2264 bitsize = nunits * BITS_PER_UNIT;
2265 nelts = CEIL (bitsize, 32);
2266 units_per = 32 / BITS_PER_UNIT;
2268 real_to_target (data, &d, mode);
2270 /* Put out the first word with the specified alignment. */
2271 assemble_integer (GEN_INT (data[0]), MIN (nunits, units_per), align, 1);
2272 nunits -= units_per;
2274 /* Subsequent words need only 32-bit alignment. */
2275 align = min_align (align, 32);
2277 for (i = 1; i < nelts; i++)
2279 assemble_integer (GEN_INT (data[i]), MIN (nunits, units_per), align, 1);
2280 nunits -= units_per;
2284 /* Given an expression EXP with a constant value,
2285 reduce it to the sum of an assembler symbol and an integer.
2286 Store them both in the structure *VALUE.
2287 EXP must be reducible. */
2289 struct addr_const GTY(())
2291 rtx base;
2292 HOST_WIDE_INT offset;
2295 static void
2296 decode_addr_const (tree exp, struct addr_const *value)
2298 tree target = TREE_OPERAND (exp, 0);
2299 int offset = 0;
2300 rtx x;
2302 while (1)
2304 if (TREE_CODE (target) == COMPONENT_REF
2305 && host_integerp (byte_position (TREE_OPERAND (target, 1)), 0))
2308 offset += int_byte_position (TREE_OPERAND (target, 1));
2309 target = TREE_OPERAND (target, 0);
2311 else if (TREE_CODE (target) == ARRAY_REF
2312 || TREE_CODE (target) == ARRAY_RANGE_REF)
2314 offset += (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (target)), 1)
2315 * tree_low_cst (TREE_OPERAND (target, 1), 0));
2316 target = TREE_OPERAND (target, 0);
2318 else
2319 break;
2322 switch (TREE_CODE (target))
2324 case VAR_DECL:
2325 case FUNCTION_DECL:
2326 x = DECL_RTL (target);
2327 break;
2329 case LABEL_DECL:
2330 x = gen_rtx_MEM (FUNCTION_MODE,
2331 gen_rtx_LABEL_REF (Pmode, force_label_rtx (target)));
2332 break;
2334 case REAL_CST:
2335 case STRING_CST:
2336 case COMPLEX_CST:
2337 case CONSTRUCTOR:
2338 case INTEGER_CST:
2339 x = output_constant_def (target, 1);
2340 break;
2342 default:
2343 gcc_unreachable ();
2346 gcc_assert (MEM_P (x));
2347 x = XEXP (x, 0);
2349 value->base = x;
2350 value->offset = offset;
2353 /* Uniquize all constants that appear in memory.
2354 Each constant in memory thus far output is recorded
2355 in `const_desc_table'. */
2357 struct constant_descriptor_tree GTY(())
2359 /* A MEM for the constant. */
2360 rtx rtl;
2362 /* The value of the constant. */
2363 tree value;
2365 /* Hash of value. Computing the hash from value each time
2366 hashfn is called can't work properly, as that means recursive
2367 use of the hash table during hash table expansion. */
2368 hashval_t hash;
2371 static GTY((param_is (struct constant_descriptor_tree)))
2372 htab_t const_desc_htab;
2374 static struct constant_descriptor_tree * build_constant_desc (tree);
2375 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2377 /* Compute a hash code for a constant expression. */
2379 static hashval_t
2380 const_desc_hash (const void *ptr)
2382 return ((struct constant_descriptor_tree *)ptr)->hash;
2385 static hashval_t
2386 const_hash_1 (const tree exp)
2388 const char *p;
2389 hashval_t hi;
2390 int len, i;
2391 enum tree_code code = TREE_CODE (exp);
2393 /* Either set P and LEN to the address and len of something to hash and
2394 exit the switch or return a value. */
2396 switch (code)
2398 case INTEGER_CST:
2399 p = (char *) &TREE_INT_CST (exp);
2400 len = sizeof TREE_INT_CST (exp);
2401 break;
2403 case REAL_CST:
2404 return real_hash (TREE_REAL_CST_PTR (exp));
2406 case STRING_CST:
2407 p = TREE_STRING_POINTER (exp);
2408 len = TREE_STRING_LENGTH (exp);
2409 break;
2411 case COMPLEX_CST:
2412 return (const_hash_1 (TREE_REALPART (exp)) * 5
2413 + const_hash_1 (TREE_IMAGPART (exp)));
2415 case CONSTRUCTOR:
2417 tree link;
2419 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2421 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link))
2422 if (TREE_VALUE (link))
2423 hi = hi * 603 + const_hash_1 (TREE_VALUE (link));
2425 return hi;
2428 case ADDR_EXPR:
2429 case FDESC_EXPR:
2431 struct addr_const value;
2433 decode_addr_const (exp, &value);
2434 switch (GET_CODE (value.base))
2436 case SYMBOL_REF:
2437 /* Don't hash the address of the SYMBOL_REF;
2438 only use the offset and the symbol name. */
2439 hi = value.offset;
2440 p = XSTR (value.base, 0);
2441 for (i = 0; p[i] != 0; i++)
2442 hi = ((hi * 613) + (unsigned) (p[i]));
2443 break;
2445 case LABEL_REF:
2446 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13;
2447 break;
2449 default:
2450 gcc_unreachable ();
2453 return hi;
2455 case PLUS_EXPR:
2456 case MINUS_EXPR:
2457 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2458 + const_hash_1 (TREE_OPERAND (exp, 1)));
2460 case NOP_EXPR:
2461 case CONVERT_EXPR:
2462 case NON_LVALUE_EXPR:
2463 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
2465 default:
2466 /* A language specific constant. Just hash the code. */
2467 return code;
2470 /* Compute hashing function. */
2471 hi = len;
2472 for (i = 0; i < len; i++)
2473 hi = ((hi * 613) + (unsigned) (p[i]));
2475 return hi;
2478 /* Wrapper of compare_constant, for the htab interface. */
2479 static int
2480 const_desc_eq (const void *p1, const void *p2)
2482 const struct constant_descriptor_tree *c1 = p1;
2483 const struct constant_descriptor_tree *c2 = p2;
2484 if (c1->hash != c2->hash)
2485 return 0;
2486 return compare_constant (c1->value, c2->value);
2489 /* Compare t1 and t2, and return 1 only if they are known to result in
2490 the same bit pattern on output. */
2492 static int
2493 compare_constant (const tree t1, const tree t2)
2495 enum tree_code typecode;
2497 if (t1 == NULL_TREE)
2498 return t2 == NULL_TREE;
2499 if (t2 == NULL_TREE)
2500 return 0;
2502 if (TREE_CODE (t1) != TREE_CODE (t2))
2503 return 0;
2505 switch (TREE_CODE (t1))
2507 case INTEGER_CST:
2508 /* Integer constants are the same only if the same width of type. */
2509 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2510 return 0;
2511 return tree_int_cst_equal (t1, t2);
2513 case REAL_CST:
2514 /* Real constants are the same only if the same width of type. */
2515 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2516 return 0;
2518 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
2520 case STRING_CST:
2521 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2522 return 0;
2524 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
2525 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
2526 TREE_STRING_LENGTH (t1)));
2528 case COMPLEX_CST:
2529 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
2530 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
2532 case CONSTRUCTOR:
2534 tree l1, l2;
2536 typecode = TREE_CODE (TREE_TYPE (t1));
2537 if (typecode != TREE_CODE (TREE_TYPE (t2)))
2538 return 0;
2540 if (typecode == ARRAY_TYPE)
2542 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
2543 /* For arrays, check that the sizes all match. */
2544 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
2545 || size_1 == -1
2546 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
2547 return 0;
2549 else
2551 /* For record and union constructors, require exact type
2552 equality. */
2553 if (TREE_TYPE (t1) != TREE_TYPE (t2))
2554 return 0;
2557 for (l1 = CONSTRUCTOR_ELTS (t1), l2 = CONSTRUCTOR_ELTS (t2);
2558 l1 && l2;
2559 l1 = TREE_CHAIN (l1), l2 = TREE_CHAIN (l2))
2561 /* Check that each value is the same... */
2562 if (! compare_constant (TREE_VALUE (l1), TREE_VALUE (l2)))
2563 return 0;
2564 /* ... and that they apply to the same fields! */
2565 if (typecode == ARRAY_TYPE)
2567 if (! compare_constant (TREE_PURPOSE (l1),
2568 TREE_PURPOSE (l2)))
2569 return 0;
2571 else
2573 if (TREE_PURPOSE (l1) != TREE_PURPOSE (l2))
2574 return 0;
2578 return l1 == NULL_TREE && l2 == NULL_TREE;
2581 case ADDR_EXPR:
2582 case FDESC_EXPR:
2584 struct addr_const value1, value2;
2586 decode_addr_const (t1, &value1);
2587 decode_addr_const (t2, &value2);
2588 return (value1.offset == value2.offset
2589 && strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
2592 case PLUS_EXPR:
2593 case MINUS_EXPR:
2594 case RANGE_EXPR:
2595 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
2596 && compare_constant(TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
2598 case NOP_EXPR:
2599 case CONVERT_EXPR:
2600 case NON_LVALUE_EXPR:
2601 case VIEW_CONVERT_EXPR:
2602 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
2604 default:
2606 tree nt1, nt2;
2607 nt1 = lang_hooks.expand_constant (t1);
2608 nt2 = lang_hooks.expand_constant (t2);
2609 if (nt1 != t1 || nt2 != t2)
2610 return compare_constant (nt1, nt2);
2611 else
2612 return 0;
2616 gcc_unreachable ();
2619 /* Make a copy of the whole tree structure for a constant. This
2620 handles the same types of nodes that compare_constant handles. */
2622 static tree
2623 copy_constant (tree exp)
2625 switch (TREE_CODE (exp))
2627 case ADDR_EXPR:
2628 /* For ADDR_EXPR, we do not want to copy the decl whose address
2629 is requested. We do want to copy constants though. */
2630 if (CONSTANT_CLASS_P (TREE_OPERAND (exp, 0)))
2631 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
2632 copy_constant (TREE_OPERAND (exp, 0)));
2633 else
2634 return copy_node (exp);
2636 case INTEGER_CST:
2637 case REAL_CST:
2638 case STRING_CST:
2639 return copy_node (exp);
2641 case COMPLEX_CST:
2642 return build_complex (TREE_TYPE (exp),
2643 copy_constant (TREE_REALPART (exp)),
2644 copy_constant (TREE_IMAGPART (exp)));
2646 case PLUS_EXPR:
2647 case MINUS_EXPR:
2648 return build2 (TREE_CODE (exp), TREE_TYPE (exp),
2649 copy_constant (TREE_OPERAND (exp, 0)),
2650 copy_constant (TREE_OPERAND (exp, 1)));
2652 case NOP_EXPR:
2653 case CONVERT_EXPR:
2654 case NON_LVALUE_EXPR:
2655 case VIEW_CONVERT_EXPR:
2656 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
2657 copy_constant (TREE_OPERAND (exp, 0)));
2659 case CONSTRUCTOR:
2661 tree copy = copy_node (exp);
2662 tree list = copy_list (CONSTRUCTOR_ELTS (exp));
2663 tree tail;
2665 CONSTRUCTOR_ELTS (copy) = list;
2666 for (tail = list; tail; tail = TREE_CHAIN (tail))
2667 TREE_VALUE (tail) = copy_constant (TREE_VALUE (tail));
2669 return copy;
2672 default:
2674 tree t = lang_hooks.expand_constant (exp);
2676 gcc_assert (t == exp);
2677 return copy_constant (t);
2682 /* Subroutine of output_constant_def:
2683 No constant equal to EXP is known to have been output.
2684 Make a constant descriptor to enter EXP in the hash table.
2685 Assign the label number and construct RTL to refer to the
2686 constant's location in memory.
2687 Caller is responsible for updating the hash table. */
2689 static struct constant_descriptor_tree *
2690 build_constant_desc (tree exp)
2692 rtx symbol;
2693 rtx rtl;
2694 char label[256];
2695 int labelno;
2696 struct constant_descriptor_tree *desc;
2698 desc = ggc_alloc (sizeof (*desc));
2699 desc->value = copy_constant (exp);
2701 /* Propagate marked-ness to copied constant. */
2702 if (flag_mudflap && mf_marked_p (exp))
2703 mf_mark (desc->value);
2705 /* Create a string containing the label name, in LABEL. */
2706 labelno = const_labelno++;
2707 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
2709 /* We have a symbol name; construct the SYMBOL_REF and the MEM. */
2710 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
2711 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2712 SYMBOL_REF_DECL (symbol) = desc->value;
2713 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
2715 rtl = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)), symbol);
2716 set_mem_attributes (rtl, exp, 1);
2717 set_mem_alias_set (rtl, 0);
2718 set_mem_alias_set (rtl, const_alias_set);
2720 /* Set flags or add text to the name to record information, such as
2721 that it is a local symbol. If the name is changed, the macro
2722 ASM_OUTPUT_LABELREF will have to know how to strip this
2723 information. This call might invalidate our local variable
2724 SYMBOL; we can't use it afterward. */
2726 targetm.encode_section_info (exp, rtl, true);
2728 desc->rtl = rtl;
2730 return desc;
2733 /* Return an rtx representing a reference to constant data in memory
2734 for the constant expression EXP.
2736 If assembler code for such a constant has already been output,
2737 return an rtx to refer to it.
2738 Otherwise, output such a constant in memory
2739 and generate an rtx for it.
2741 If DEFER is nonzero, this constant can be deferred and output only
2742 if referenced in the function after all optimizations.
2744 `const_desc_table' records which constants already have label strings. */
2747 output_constant_def (tree exp, int defer)
2749 struct constant_descriptor_tree *desc;
2750 struct constant_descriptor_tree key;
2751 void **loc;
2753 /* Look up EXP in the table of constant descriptors. If we didn't find
2754 it, create a new one. */
2755 key.value = exp;
2756 key.hash = const_hash_1 (exp);
2757 loc = htab_find_slot_with_hash (const_desc_htab, &key, key.hash, INSERT);
2759 desc = *loc;
2760 if (desc == 0)
2762 desc = build_constant_desc (exp);
2763 desc->hash = key.hash;
2764 *loc = desc;
2767 maybe_output_constant_def_contents (desc, defer);
2768 return desc->rtl;
2771 /* Subroutine of output_constant_def: Decide whether or not we need to
2772 output the constant DESC now, and if so, do it. */
2773 static void
2774 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
2775 int defer)
2777 rtx symbol = XEXP (desc->rtl, 0);
2778 tree exp = desc->value;
2780 if (flag_syntax_only)
2781 return;
2783 if (TREE_ASM_WRITTEN (exp))
2784 /* Already output; don't do it again. */
2785 return;
2787 /* We can always defer constants as long as the context allows
2788 doing so. */
2789 if (defer)
2791 /* Increment n_deferred_constants if it exists. It needs to be at
2792 least as large as the number of constants actually referred to
2793 by the function. If it's too small we'll stop looking too early
2794 and fail to emit constants; if it's too large we'll only look
2795 through the entire function when we could have stopped earlier. */
2796 if (cfun)
2797 n_deferred_constants++;
2798 return;
2801 output_constant_def_contents (symbol);
2804 /* We must output the constant data referred to by SYMBOL; do so. */
2806 static void
2807 output_constant_def_contents (rtx symbol)
2809 tree exp = SYMBOL_REF_DECL (symbol);
2810 const char *label = XSTR (symbol, 0);
2811 HOST_WIDE_INT size;
2813 /* Make sure any other constants whose addresses appear in EXP
2814 are assigned label numbers. */
2815 int reloc = compute_reloc_for_constant (exp);
2817 /* Align the location counter as required by EXP's data type. */
2818 unsigned int align = TYPE_ALIGN (TREE_TYPE (exp));
2819 #ifdef CONSTANT_ALIGNMENT
2820 align = CONSTANT_ALIGNMENT (exp, align);
2821 #endif
2823 output_addressed_constants (exp);
2825 /* We are no longer deferring this constant. */
2826 TREE_ASM_WRITTEN (exp) = 1;
2828 if (IN_NAMED_SECTION (exp))
2829 named_section (exp, NULL, reloc);
2830 else
2831 targetm.asm_out.select_section (exp, reloc, align);
2833 if (align > BITS_PER_UNIT)
2835 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2838 size = int_size_in_bytes (TREE_TYPE (exp));
2839 if (TREE_CODE (exp) == STRING_CST)
2840 size = MAX (TREE_STRING_LENGTH (exp), size);
2842 /* Do any machine/system dependent processing of the constant. */
2843 #ifdef ASM_DECLARE_CONSTANT_NAME
2844 ASM_DECLARE_CONSTANT_NAME (asm_out_file, label, exp, size);
2845 #else
2846 /* Standard thing is just output label for the constant. */
2847 ASM_OUTPUT_LABEL (asm_out_file, label);
2848 #endif /* ASM_DECLARE_CONSTANT_NAME */
2850 /* Output the value of EXP. */
2851 output_constant (exp, size, align);
2852 if (flag_mudflap)
2853 mudflap_enqueue_constant (exp);
2856 /* Look up EXP in the table of constant descriptors. Return the rtl
2857 if it has been emitted, else null. */
2860 lookup_constant_def (tree exp)
2862 struct constant_descriptor_tree *desc;
2863 struct constant_descriptor_tree key;
2865 key.value = exp;
2866 key.hash = const_hash_1 (exp);
2867 desc = htab_find_with_hash (const_desc_htab, &key, key.hash);
2869 return (desc ? desc->rtl : NULL_RTX);
2872 /* Used in the hash tables to avoid outputting the same constant
2873 twice. Unlike 'struct constant_descriptor_tree', RTX constants
2874 are output once per function, not once per file. */
2875 /* ??? Only a few targets need per-function constant pools. Most
2876 can use one per-file pool. Should add a targetm bit to tell the
2877 difference. */
2879 struct rtx_constant_pool GTY(())
2881 /* Pointers to first and last constant in pool, as ordered by offset. */
2882 struct constant_descriptor_rtx *first;
2883 struct constant_descriptor_rtx *last;
2885 /* Hash facility for making memory-constants from constant rtl-expressions.
2886 It is used on RISC machines where immediate integer arguments and
2887 constant addresses are restricted so that such constants must be stored
2888 in memory. */
2889 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_htab;
2890 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_sym_htab;
2892 /* Current offset in constant pool (does not include any
2893 machine-specific header). */
2894 HOST_WIDE_INT offset;
2897 struct constant_descriptor_rtx GTY((chain_next ("%h.next")))
2899 struct constant_descriptor_rtx *next;
2900 rtx mem;
2901 rtx sym;
2902 rtx constant;
2903 HOST_WIDE_INT offset;
2904 hashval_t hash;
2905 enum machine_mode mode;
2906 unsigned int align;
2907 int labelno;
2908 int mark;
2911 /* Hash and compare functions for const_rtx_htab. */
2913 static hashval_t
2914 const_desc_rtx_hash (const void *ptr)
2916 const struct constant_descriptor_rtx *desc = ptr;
2917 return desc->hash;
2920 static int
2921 const_desc_rtx_eq (const void *a, const void *b)
2923 const struct constant_descriptor_rtx *x = a;
2924 const struct constant_descriptor_rtx *y = b;
2926 if (x->mode != y->mode)
2927 return 0;
2928 return rtx_equal_p (x->constant, y->constant);
2931 /* Hash and compare functions for const_rtx_sym_htab. */
2933 static hashval_t
2934 const_desc_rtx_sym_hash (const void *ptr)
2936 const struct constant_descriptor_rtx *desc = ptr;
2937 return htab_hash_string (XSTR (desc->sym, 0));
2940 static int
2941 const_desc_rtx_sym_eq (const void *a, const void *b)
2943 const struct constant_descriptor_rtx *x = a;
2944 const struct constant_descriptor_rtx *y = b;
2945 return XSTR (x->sym, 0) == XSTR (y->sym, 0);
2948 /* This is the worker function for const_rtx_hash, called via for_each_rtx. */
2950 static int
2951 const_rtx_hash_1 (rtx *xp, void *data)
2953 unsigned HOST_WIDE_INT hwi;
2954 enum machine_mode mode;
2955 enum rtx_code code;
2956 hashval_t h, *hp;
2957 rtx x;
2959 x = *xp;
2960 code = GET_CODE (x);
2961 mode = GET_MODE (x);
2962 h = (hashval_t) code * 1048573 + mode;
2964 switch (code)
2966 case CONST_INT:
2967 hwi = INTVAL (x);
2968 fold_hwi:
2970 const int shift = sizeof (hashval_t) * CHAR_BIT;
2971 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
2972 int i;
2974 h ^= (hashval_t) hwi;
2975 for (i = 1; i < n; ++i)
2977 hwi >>= shift;
2978 h ^= (hashval_t) hwi;
2981 break;
2983 case CONST_DOUBLE:
2984 if (mode == VOIDmode)
2986 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
2987 goto fold_hwi;
2989 else
2990 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
2991 break;
2993 case CONST_VECTOR:
2995 int i;
2996 for (i = XVECLEN (x, 0); i-- > 0; )
2997 h = h * 251 + const_rtx_hash_1 (&XVECEXP (x, 0, i), data);
2999 break;
3001 case SYMBOL_REF:
3002 h ^= htab_hash_string (XSTR (x, 0));
3003 break;
3005 case LABEL_REF:
3006 h = h * 251 + CODE_LABEL_NUMBER (XEXP (x, 0));
3007 break;
3009 case UNSPEC:
3010 case UNSPEC_VOLATILE:
3011 h = h * 251 + XINT (x, 1);
3012 break;
3014 default:
3015 break;
3018 hp = data;
3019 *hp = *hp * 509 + h;
3020 return 0;
3023 /* Compute a hash value for X, which should be a constant. */
3025 static hashval_t
3026 const_rtx_hash (rtx x)
3028 hashval_t h = 0;
3029 for_each_rtx (&x, const_rtx_hash_1, &h);
3030 return h;
3034 /* Initialize constant pool hashing for a new function. */
3036 void
3037 init_varasm_status (struct function *f)
3039 struct varasm_status *p;
3040 struct rtx_constant_pool *pool;
3042 p = ggc_alloc (sizeof (struct varasm_status));
3043 f->varasm = p;
3045 pool = ggc_alloc (sizeof (struct rtx_constant_pool));
3046 p->pool = pool;
3047 p->deferred_constants = 0;
3049 pool->const_rtx_htab = htab_create_ggc (31, const_desc_rtx_hash,
3050 const_desc_rtx_eq, NULL);
3051 pool->const_rtx_sym_htab = htab_create_ggc (31, const_desc_rtx_sym_hash,
3052 const_desc_rtx_sym_eq, NULL);
3053 pool->first = pool->last = NULL;
3054 pool->offset = 0;
3057 /* Given a MINUS expression, simplify it if both sides
3058 include the same symbol. */
3061 simplify_subtraction (rtx x)
3063 rtx r = simplify_rtx (x);
3064 return r ? r : x;
3067 /* Given a constant rtx X, make (or find) a memory constant for its value
3068 and return a MEM rtx to refer to it in memory. */
3071 force_const_mem (enum machine_mode mode, rtx x)
3073 struct constant_descriptor_rtx *desc, tmp;
3074 struct rtx_constant_pool *pool = cfun->varasm->pool;
3075 char label[256];
3076 rtx def, symbol;
3077 hashval_t hash;
3078 unsigned int align;
3079 void **slot;
3081 /* If we're not allowed to drop X into the constant pool, don't. */
3082 if (targetm.cannot_force_const_mem (x))
3083 return NULL_RTX;
3085 /* Lookup the value in the hashtable. */
3086 tmp.constant = x;
3087 tmp.mode = mode;
3088 hash = const_rtx_hash (x);
3089 slot = htab_find_slot_with_hash (pool->const_rtx_htab, &tmp, hash, INSERT);
3090 desc = *slot;
3092 /* If the constant was already present, return its memory. */
3093 if (desc)
3094 return copy_rtx (desc->mem);
3096 /* Otherwise, create a new descriptor. */
3097 desc = ggc_alloc (sizeof (*desc));
3098 *slot = desc;
3100 /* Align the location counter as required by EXP's data type. */
3101 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3102 #ifdef CONSTANT_ALIGNMENT
3104 tree type = lang_hooks.types.type_for_mode (mode, 0);
3105 if (type != NULL_TREE)
3106 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
3108 #endif
3110 pool->offset += (align / BITS_PER_UNIT) - 1;
3111 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
3113 desc->next = NULL;
3114 desc->constant = tmp.constant;
3115 desc->offset = pool->offset;
3116 desc->hash = hash;
3117 desc->mode = mode;
3118 desc->align = align;
3119 desc->labelno = const_labelno;
3120 desc->mark = 0;
3122 pool->offset += GET_MODE_SIZE (mode);
3123 if (pool->last)
3124 pool->last->next = desc;
3125 else
3126 pool->first = pool->last = desc;
3127 pool->last = desc;
3129 /* Create a string containing the label name, in LABEL. */
3130 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3131 ++const_labelno;
3133 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
3134 the constants pool. */
3135 desc->sym = symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
3136 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
3137 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
3138 current_function_uses_const_pool = 1;
3140 /* Insert the descriptor into the symbol cross-reference table too. */
3141 slot = htab_find_slot (pool->const_rtx_sym_htab, desc, INSERT);
3142 gcc_assert (!*slot);
3143 *slot = desc;
3145 /* Construct the MEM. */
3146 desc->mem = def = gen_const_mem (mode, symbol);
3147 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3148 set_mem_align (def, align);
3150 /* If we're dropping a label to the constant pool, make sure we
3151 don't delete it. */
3152 if (GET_CODE (x) == LABEL_REF)
3153 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3155 return copy_rtx (def);
3158 /* Given a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true, return a pointer to
3159 the corresponding constant_descriptor_rtx structure. */
3161 static struct constant_descriptor_rtx *
3162 find_pool_constant (struct rtx_constant_pool *pool, rtx sym)
3164 struct constant_descriptor_rtx tmp;
3165 tmp.sym = sym;
3166 return htab_find (pool->const_rtx_sym_htab, &tmp);
3169 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3172 get_pool_constant (rtx addr)
3174 return find_pool_constant (cfun->varasm->pool, addr)->constant;
3177 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3178 and whether it has been output or not. */
3181 get_pool_constant_mark (rtx addr, bool *pmarked)
3183 struct constant_descriptor_rtx *desc;
3185 desc = find_pool_constant (cfun->varasm->pool, addr);
3186 *pmarked = (desc->mark != 0);
3187 return desc->constant;
3190 /* Likewise, but for the constant pool of a specific function. */
3193 get_pool_constant_for_function (struct function *f, rtx addr)
3195 return find_pool_constant (f->varasm->pool, addr)->constant;
3198 /* Similar, return the mode. */
3200 enum machine_mode
3201 get_pool_mode (rtx addr)
3203 return find_pool_constant (cfun->varasm->pool, addr)->mode;
3206 /* Return the size of the constant pool. */
3209 get_pool_size (void)
3211 return cfun->varasm->pool->offset;
3214 /* Worker function for output_constant_pool_1. Emit assembly for X
3215 in MODE with known alignment ALIGN. */
3217 static void
3218 output_constant_pool_2 (enum machine_mode mode, rtx x, unsigned int align)
3220 switch (GET_MODE_CLASS (mode))
3222 case MODE_FLOAT:
3224 REAL_VALUE_TYPE r;
3226 gcc_assert (GET_CODE (x) == CONST_DOUBLE);
3227 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3228 assemble_real (r, mode, align);
3229 break;
3232 case MODE_INT:
3233 case MODE_PARTIAL_INT:
3234 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3235 break;
3237 case MODE_VECTOR_FLOAT:
3238 case MODE_VECTOR_INT:
3240 int i, units;
3241 enum machine_mode submode = GET_MODE_INNER (mode);
3242 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3244 gcc_assert (GET_CODE (x) == CONST_VECTOR);
3245 units = CONST_VECTOR_NUNITS (x);
3247 for (i = 0; i < units; i++)
3249 rtx elt = CONST_VECTOR_ELT (x, i);
3250 output_constant_pool_2 (submode, elt, i ? subalign : align);
3253 break;
3255 default:
3256 gcc_unreachable ();
3260 /* Worker function for output_constant_pool. Emit POOL. */
3262 static void
3263 output_constant_pool_1 (struct constant_descriptor_rtx *desc)
3265 rtx x, tmp;
3267 if (!desc->mark)
3268 return;
3269 x = desc->constant;
3271 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3272 whose CODE_LABEL has been deleted. This can occur if a jump table
3273 is eliminated by optimization. If so, write a constant of zero
3274 instead. Note that this can also happen by turning the
3275 CODE_LABEL into a NOTE. */
3276 /* ??? This seems completely and utterly wrong. Certainly it's
3277 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3278 functioning even with INSN_DELETED_P and friends. */
3280 tmp = x;
3281 switch (GET_CODE (x))
3283 case CONST:
3284 if (GET_CODE (XEXP (x, 0)) != PLUS
3285 || GET_CODE (XEXP (XEXP (x, 0), 0)) != LABEL_REF)
3286 break;
3287 tmp = XEXP (XEXP (x, 0), 0);
3288 /* FALLTHRU */
3290 case LABEL_REF:
3291 tmp = XEXP (x, 0);
3292 gcc_assert (!INSN_DELETED_P (tmp));
3293 gcc_assert (!NOTE_P (tmp)
3294 || NOTE_LINE_NUMBER (tmp) != NOTE_INSN_DELETED);
3295 break;
3297 default:
3298 break;
3301 /* First switch to correct section. */
3302 targetm.asm_out.select_rtx_section (desc->mode, x, desc->align);
3304 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3305 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3306 desc->align, desc->labelno, done);
3307 #endif
3309 assemble_align (desc->align);
3311 /* Output the label. */
3312 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3314 /* Output the data. */
3315 output_constant_pool_2 (desc->mode, x, desc->align);
3317 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3318 sections have proper size. */
3319 if (desc->align > GET_MODE_BITSIZE (desc->mode)
3320 && in_section == in_named
3321 && get_named_section_flags (in_named_name) & SECTION_MERGE)
3322 assemble_align (desc->align);
3324 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3325 done:
3326 #endif
3327 return;
3330 /* Given a SYMBOL_REF CURRENT_RTX, mark it and all constants it refers
3331 to as used. Emit referenced deferred strings. This function can
3332 be used with for_each_rtx to mark all SYMBOL_REFs in an rtx. */
3334 static int
3335 mark_constant (rtx *current_rtx, void *data)
3337 struct rtx_constant_pool *pool = data;
3338 rtx x = *current_rtx;
3340 if (x == NULL_RTX || GET_CODE (x) != SYMBOL_REF)
3341 return 0;
3343 if (CONSTANT_POOL_ADDRESS_P (x))
3345 struct constant_descriptor_rtx *desc = find_pool_constant (pool, x);
3346 if (desc->mark == 0)
3348 desc->mark = 1;
3349 for_each_rtx (&desc->constant, mark_constant, pool);
3352 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3354 tree exp = SYMBOL_REF_DECL (x);
3355 if (!TREE_ASM_WRITTEN (exp))
3357 n_deferred_constants--;
3358 output_constant_def_contents (x);
3362 return -1;
3365 /* Look through appropriate parts of INSN, marking all entries in the
3366 constant pool which are actually being used. Entries that are only
3367 referenced by other constants are also marked as used. Emit
3368 deferred strings that are used. */
3370 static void
3371 mark_constants (struct rtx_constant_pool *pool, rtx insn)
3373 if (!INSN_P (insn))
3374 return;
3376 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3377 insns, not any notes that may be attached. We don't want to mark
3378 a constant just because it happens to appear in a REG_EQUIV note. */
3379 if (GET_CODE (PATTERN (insn)) == SEQUENCE)
3381 rtx seq = PATTERN (insn);
3382 int i, n = XVECLEN (seq, 0);
3383 for (i = 0; i < n; ++i)
3385 rtx subinsn = XVECEXP (seq, 0, i);
3386 if (INSN_P (subinsn))
3387 for_each_rtx (&PATTERN (subinsn), mark_constant, pool);
3390 else
3391 for_each_rtx (&PATTERN (insn), mark_constant, pool);
3394 /* Look through the instructions for this function, and mark all the
3395 entries in POOL which are actually being used. Emit deferred constants
3396 which have indeed been used. */
3398 static void
3399 mark_constant_pool (struct rtx_constant_pool *pool)
3401 rtx insn, link;
3403 if (pool->first == 0 && n_deferred_constants == 0)
3404 return;
3406 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3407 mark_constants (pool, insn);
3409 for (link = current_function_epilogue_delay_list;
3410 link;
3411 link = XEXP (link, 1))
3412 mark_constants (pool, XEXP (link, 0));
3415 /* Write all the constants in the constant pool. */
3417 void
3418 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
3419 tree fndecl ATTRIBUTE_UNUSED)
3421 struct rtx_constant_pool *pool = cfun->varasm->pool;
3422 struct constant_descriptor_rtx *desc;
3424 /* It is possible for gcc to call force_const_mem and then to later
3425 discard the instructions which refer to the constant. In such a
3426 case we do not need to output the constant. */
3427 mark_constant_pool (pool);
3429 #ifdef ASM_OUTPUT_POOL_PROLOGUE
3430 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
3431 #endif
3433 for (desc = pool->first; desc ; desc = desc->next)
3434 output_constant_pool_1 (desc);
3436 #ifdef ASM_OUTPUT_POOL_EPILOGUE
3437 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
3438 #endif
3441 /* Determine what kind of relocations EXP may need. */
3444 compute_reloc_for_constant (tree exp)
3446 int reloc = 0, reloc2;
3447 tree tem;
3449 /* Give the front-end a chance to convert VALUE to something that
3450 looks more like a constant to the back-end. */
3451 exp = lang_hooks.expand_constant (exp);
3453 switch (TREE_CODE (exp))
3455 case ADDR_EXPR:
3456 case FDESC_EXPR:
3457 /* Go inside any operations that get_inner_reference can handle and see
3458 if what's inside is a constant: no need to do anything here for
3459 addresses of variables or functions. */
3460 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
3461 tem = TREE_OPERAND (tem, 0))
3464 if (TREE_PUBLIC (tem))
3465 reloc |= 2;
3466 else
3467 reloc |= 1;
3468 break;
3470 case PLUS_EXPR:
3471 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3472 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
3473 break;
3475 case MINUS_EXPR:
3476 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3477 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
3478 /* The difference of two local labels is computable at link time. */
3479 if (reloc == 1 && reloc2 == 1)
3480 reloc = 0;
3481 else
3482 reloc |= reloc2;
3483 break;
3485 case NOP_EXPR:
3486 case CONVERT_EXPR:
3487 case NON_LVALUE_EXPR:
3488 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3489 break;
3491 case CONSTRUCTOR:
3492 for (tem = CONSTRUCTOR_ELTS (exp); tem; tem = TREE_CHAIN (tem))
3493 if (TREE_VALUE (tem) != 0)
3494 reloc |= compute_reloc_for_constant (TREE_VALUE (tem));
3496 break;
3498 default:
3499 break;
3501 return reloc;
3504 /* Find all the constants whose addresses are referenced inside of EXP,
3505 and make sure assembler code with a label has been output for each one.
3506 Indicate whether an ADDR_EXPR has been encountered. */
3508 static void
3509 output_addressed_constants (tree exp)
3511 tree tem;
3513 /* Give the front-end a chance to convert VALUE to something that
3514 looks more like a constant to the back-end. */
3515 exp = lang_hooks.expand_constant (exp);
3517 switch (TREE_CODE (exp))
3519 case ADDR_EXPR:
3520 case FDESC_EXPR:
3521 /* Go inside any operations that get_inner_reference can handle and see
3522 if what's inside is a constant: no need to do anything here for
3523 addresses of variables or functions. */
3524 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
3525 tem = TREE_OPERAND (tem, 0))
3528 /* If we have an initialized CONST_DECL, retrieve the initializer. */
3529 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
3530 tem = DECL_INITIAL (tem);
3532 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
3533 output_constant_def (tem, 0);
3534 break;
3536 case PLUS_EXPR:
3537 case MINUS_EXPR:
3538 output_addressed_constants (TREE_OPERAND (exp, 1));
3539 /* Fall through. */
3541 case NOP_EXPR:
3542 case CONVERT_EXPR:
3543 case NON_LVALUE_EXPR:
3544 output_addressed_constants (TREE_OPERAND (exp, 0));
3545 break;
3547 case CONSTRUCTOR:
3548 for (tem = CONSTRUCTOR_ELTS (exp); tem; tem = TREE_CHAIN (tem))
3549 if (TREE_VALUE (tem) != 0)
3550 output_addressed_constants (TREE_VALUE (tem));
3552 break;
3554 default:
3555 break;
3559 /* Return nonzero if VALUE is a valid constant-valued expression
3560 for use in initializing a static variable; one that can be an
3561 element of a "constant" initializer.
3563 Return null_pointer_node if the value is absolute;
3564 if it is relocatable, return the variable that determines the relocation.
3565 We assume that VALUE has been folded as much as possible;
3566 therefore, we do not need to check for such things as
3567 arithmetic-combinations of integers. */
3569 tree
3570 initializer_constant_valid_p (tree value, tree endtype)
3572 /* Give the front-end a chance to convert VALUE to something that
3573 looks more like a constant to the back-end. */
3574 value = lang_hooks.expand_constant (value);
3576 switch (TREE_CODE (value))
3578 case CONSTRUCTOR:
3579 if ((TREE_CODE (TREE_TYPE (value)) == UNION_TYPE
3580 || TREE_CODE (TREE_TYPE (value)) == RECORD_TYPE)
3581 && TREE_CONSTANT (value)
3582 && CONSTRUCTOR_ELTS (value))
3584 tree elt;
3585 bool absolute = true;
3587 for (elt = CONSTRUCTOR_ELTS (value); elt; elt = TREE_CHAIN (elt))
3589 tree reloc;
3590 value = TREE_VALUE (elt);
3591 reloc = initializer_constant_valid_p (value, TREE_TYPE (value));
3592 if (!reloc)
3593 return NULL_TREE;
3594 if (reloc != null_pointer_node)
3595 absolute = false;
3597 /* For a non-absolute relocation, there is no single
3598 variable that can be "the variable that determines the
3599 relocation." */
3600 return absolute ? null_pointer_node : error_mark_node;
3603 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
3605 case INTEGER_CST:
3606 case VECTOR_CST:
3607 case REAL_CST:
3608 case STRING_CST:
3609 case COMPLEX_CST:
3610 return null_pointer_node;
3612 case ADDR_EXPR:
3613 case FDESC_EXPR:
3614 value = staticp (TREE_OPERAND (value, 0));
3615 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out to
3616 be a constant, this is old-skool offsetof-like nonsense. */
3617 if (value
3618 && TREE_CODE (value) == INDIRECT_REF
3619 && TREE_CONSTANT (TREE_OPERAND (value, 0)))
3620 return null_pointer_node;
3621 /* Taking the address of a nested function involves a trampoline. */
3622 if (value
3623 && TREE_CODE (value) == FUNCTION_DECL
3624 && ((decl_function_context (value) && !DECL_NO_STATIC_CHAIN (value))
3625 || DECL_NON_ADDR_CONST_P (value)))
3626 return NULL_TREE;
3627 return value;
3629 case VIEW_CONVERT_EXPR:
3630 case NON_LVALUE_EXPR:
3631 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3633 case CONVERT_EXPR:
3634 case NOP_EXPR:
3636 tree src;
3637 tree src_type;
3638 tree dest_type;
3640 src = TREE_OPERAND (value, 0);
3641 src_type = TREE_TYPE (src);
3642 dest_type = TREE_TYPE (value);
3644 /* Allow conversions between pointer types, floating-point
3645 types, and offset types. */
3646 if ((POINTER_TYPE_P (dest_type) && POINTER_TYPE_P (src_type))
3647 || (FLOAT_TYPE_P (dest_type) && FLOAT_TYPE_P (src_type))
3648 || (TREE_CODE (dest_type) == OFFSET_TYPE
3649 && TREE_CODE (src_type) == OFFSET_TYPE))
3650 return initializer_constant_valid_p (src, endtype);
3652 /* Allow length-preserving conversions between integer types. */
3653 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type)
3654 && (TYPE_PRECISION (dest_type) == TYPE_PRECISION (src_type)))
3655 return initializer_constant_valid_p (src, endtype);
3657 /* Allow conversions between other integer types only if
3658 explicit value. */
3659 if (INTEGRAL_TYPE_P (dest_type) && INTEGRAL_TYPE_P (src_type))
3661 tree inner = initializer_constant_valid_p (src, endtype);
3662 if (inner == null_pointer_node)
3663 return null_pointer_node;
3664 break;
3667 /* Allow (int) &foo provided int is as wide as a pointer. */
3668 if (INTEGRAL_TYPE_P (dest_type) && POINTER_TYPE_P (src_type)
3669 && (TYPE_PRECISION (dest_type) >= TYPE_PRECISION (src_type)))
3670 return initializer_constant_valid_p (src, endtype);
3672 /* Likewise conversions from int to pointers, but also allow
3673 conversions from 0. */
3674 if ((POINTER_TYPE_P (dest_type)
3675 || TREE_CODE (dest_type) == OFFSET_TYPE)
3676 && INTEGRAL_TYPE_P (src_type))
3678 if (integer_zerop (src))
3679 return null_pointer_node;
3680 else if (TYPE_PRECISION (dest_type) <= TYPE_PRECISION (src_type))
3681 return initializer_constant_valid_p (src, endtype);
3684 /* Allow conversions to struct or union types if the value
3685 inside is okay. */
3686 if (TREE_CODE (dest_type) == RECORD_TYPE
3687 || TREE_CODE (dest_type) == UNION_TYPE)
3688 return initializer_constant_valid_p (src, endtype);
3690 break;
3692 case PLUS_EXPR:
3693 if (! INTEGRAL_TYPE_P (endtype)
3694 || TYPE_PRECISION (endtype) >= POINTER_SIZE)
3696 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0),
3697 endtype);
3698 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1),
3699 endtype);
3700 /* If either term is absolute, use the other terms relocation. */
3701 if (valid0 == null_pointer_node)
3702 return valid1;
3703 if (valid1 == null_pointer_node)
3704 return valid0;
3706 break;
3708 case MINUS_EXPR:
3709 if (! INTEGRAL_TYPE_P (endtype)
3710 || TYPE_PRECISION (endtype) >= POINTER_SIZE)
3712 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0),
3713 endtype);
3714 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1),
3715 endtype);
3716 /* Win if second argument is absolute. */
3717 if (valid1 == null_pointer_node)
3718 return valid0;
3719 /* Win if both arguments have the same relocation.
3720 Then the value is absolute. */
3721 if (valid0 == valid1 && valid0 != 0)
3722 return null_pointer_node;
3724 /* Since GCC guarantees that string constants are unique in the
3725 generated code, a subtraction between two copies of the same
3726 constant string is absolute. */
3727 if (valid0 && TREE_CODE (valid0) == STRING_CST
3728 && valid1 && TREE_CODE (valid1) == STRING_CST
3729 && operand_equal_p (valid0, valid1, 1))
3730 return null_pointer_node;
3733 /* Support narrowing differences. */
3734 if (INTEGRAL_TYPE_P (endtype))
3736 tree op0, op1;
3738 op0 = TREE_OPERAND (value, 0);
3739 op1 = TREE_OPERAND (value, 1);
3741 /* Like STRIP_NOPS except allow the operand mode to widen.
3742 This works around a feature of fold that simplifies
3743 (int)(p1 - p2) to ((int)p1 - (int)p2) under the theory
3744 that the narrower operation is cheaper. */
3746 while (TREE_CODE (op0) == NOP_EXPR
3747 || TREE_CODE (op0) == CONVERT_EXPR
3748 || TREE_CODE (op0) == NON_LVALUE_EXPR)
3750 tree inner = TREE_OPERAND (op0, 0);
3751 if (inner == error_mark_node
3752 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
3753 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
3754 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
3755 break;
3756 op0 = inner;
3759 while (TREE_CODE (op1) == NOP_EXPR
3760 || TREE_CODE (op1) == CONVERT_EXPR
3761 || TREE_CODE (op1) == NON_LVALUE_EXPR)
3763 tree inner = TREE_OPERAND (op1, 0);
3764 if (inner == error_mark_node
3765 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
3766 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
3767 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
3768 break;
3769 op1 = inner;
3772 op0 = initializer_constant_valid_p (op0, endtype);
3773 op1 = initializer_constant_valid_p (op1, endtype);
3775 /* Both initializers must be known. */
3776 if (op0 && op1)
3778 if (op0 == op1)
3779 return null_pointer_node;
3781 /* Support differences between labels. */
3782 if (TREE_CODE (op0) == LABEL_DECL
3783 && TREE_CODE (op1) == LABEL_DECL)
3784 return null_pointer_node;
3786 if (TREE_CODE (op0) == STRING_CST
3787 && TREE_CODE (op1) == STRING_CST
3788 && operand_equal_p (op0, op1, 1))
3789 return null_pointer_node;
3792 break;
3794 default:
3795 break;
3798 return 0;
3801 /* Output assembler code for constant EXP to FILE, with no label.
3802 This includes the pseudo-op such as ".int" or ".byte", and a newline.
3803 Assumes output_addressed_constants has been done on EXP already.
3805 Generate exactly SIZE bytes of assembler data, padding at the end
3806 with zeros if necessary. SIZE must always be specified.
3808 SIZE is important for structure constructors,
3809 since trailing members may have been omitted from the constructor.
3810 It is also important for initialization of arrays from string constants
3811 since the full length of the string constant might not be wanted.
3812 It is also needed for initialization of unions, where the initializer's
3813 type is just one member, and that may not be as long as the union.
3815 There a case in which we would fail to output exactly SIZE bytes:
3816 for a structure constructor that wants to produce more than SIZE bytes.
3817 But such constructors will never be generated for any possible input.
3819 ALIGN is the alignment of the data in bits. */
3821 void
3822 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align)
3824 enum tree_code code;
3825 unsigned HOST_WIDE_INT thissize;
3827 /* Some front-ends use constants other than the standard language-independent
3828 varieties, but which may still be output directly. Give the front-end a
3829 chance to convert EXP to a language-independent representation. */
3830 exp = lang_hooks.expand_constant (exp);
3832 if (size == 0 || flag_syntax_only)
3833 return;
3835 /* Eliminate any conversions since we'll be outputting the underlying
3836 constant. */
3837 while (TREE_CODE (exp) == NOP_EXPR || TREE_CODE (exp) == CONVERT_EXPR
3838 || TREE_CODE (exp) == NON_LVALUE_EXPR
3839 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
3840 exp = TREE_OPERAND (exp, 0);
3842 code = TREE_CODE (TREE_TYPE (exp));
3843 thissize = int_size_in_bytes (TREE_TYPE (exp));
3845 /* Allow a constructor with no elements for any data type.
3846 This means to fill the space with zeros. */
3847 if (TREE_CODE (exp) == CONSTRUCTOR && CONSTRUCTOR_ELTS (exp) == 0)
3849 assemble_zeros (size);
3850 return;
3853 if (TREE_CODE (exp) == FDESC_EXPR)
3855 #ifdef ASM_OUTPUT_FDESC
3856 HOST_WIDE_INT part = tree_low_cst (TREE_OPERAND (exp, 1), 0);
3857 tree decl = TREE_OPERAND (exp, 0);
3858 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
3859 #else
3860 gcc_unreachable ();
3861 #endif
3862 return;
3865 /* Now output the underlying data. If we've handling the padding, return.
3866 Otherwise, break and ensure SIZE is the size written. */
3867 switch (code)
3869 case CHAR_TYPE:
3870 case BOOLEAN_TYPE:
3871 case INTEGER_TYPE:
3872 case ENUMERAL_TYPE:
3873 case POINTER_TYPE:
3874 case REFERENCE_TYPE:
3875 case OFFSET_TYPE:
3876 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
3877 EXPAND_INITIALIZER),
3878 MIN (size, thissize), align, 0))
3879 error ("initializer for integer value is too complicated");
3880 break;
3882 case REAL_TYPE:
3883 if (TREE_CODE (exp) != REAL_CST)
3884 error ("initializer for floating value is not a floating constant");
3886 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)), align);
3887 break;
3889 case COMPLEX_TYPE:
3890 output_constant (TREE_REALPART (exp), thissize / 2, align);
3891 output_constant (TREE_IMAGPART (exp), thissize / 2,
3892 min_align (align, BITS_PER_UNIT * (thissize / 2)));
3893 break;
3895 case ARRAY_TYPE:
3896 case VECTOR_TYPE:
3897 switch (TREE_CODE (exp))
3899 case CONSTRUCTOR:
3900 output_constructor (exp, size, align);
3901 return;
3902 case STRING_CST:
3903 thissize = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp),
3904 size);
3905 assemble_string (TREE_STRING_POINTER (exp), thissize);
3906 break;
3908 case VECTOR_CST:
3910 int elt_size;
3911 tree link;
3912 unsigned int nalign;
3913 enum machine_mode inner;
3915 inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
3916 nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
3918 elt_size = GET_MODE_SIZE (inner);
3920 link = TREE_VECTOR_CST_ELTS (exp);
3921 output_constant (TREE_VALUE (link), elt_size, align);
3922 while ((link = TREE_CHAIN (link)) != NULL)
3923 output_constant (TREE_VALUE (link), elt_size, nalign);
3924 break;
3926 default:
3927 gcc_unreachable ();
3929 break;
3931 case RECORD_TYPE:
3932 case UNION_TYPE:
3933 gcc_assert (TREE_CODE (exp) == CONSTRUCTOR);
3934 output_constructor (exp, size, align);
3935 return;
3937 case ERROR_MARK:
3938 return;
3940 default:
3941 gcc_unreachable ();
3944 if (size > thissize)
3945 assemble_zeros (size - thissize);
3949 /* Subroutine of output_constructor, used for computing the size of
3950 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
3951 type with an unspecified upper bound. */
3953 static unsigned HOST_WIDE_INT
3954 array_size_for_constructor (tree val)
3956 tree max_index, i;
3958 /* This code used to attempt to handle string constants that are not
3959 arrays of single-bytes, but nothing else does, so there's no point in
3960 doing it here. */
3961 if (TREE_CODE (val) == STRING_CST)
3962 return TREE_STRING_LENGTH (val);
3964 max_index = NULL_TREE;
3965 for (i = CONSTRUCTOR_ELTS (val); i; i = TREE_CHAIN (i))
3967 tree index = TREE_PURPOSE (i);
3969 if (TREE_CODE (index) == RANGE_EXPR)
3970 index = TREE_OPERAND (index, 1);
3971 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
3972 max_index = index;
3975 if (max_index == NULL_TREE)
3976 return 0;
3978 /* Compute the total number of array elements. */
3979 i = size_binop (MINUS_EXPR, convert (sizetype, max_index),
3980 convert (sizetype,
3981 TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)))));
3982 i = size_binop (PLUS_EXPR, i, convert (sizetype, integer_one_node));
3984 /* Multiply by the array element unit size to find number of bytes. */
3985 i = size_binop (MULT_EXPR, i, TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
3987 return tree_low_cst (i, 1);
3990 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
3991 Generate at least SIZE bytes, padding if necessary. */
3993 static void
3994 output_constructor (tree exp, unsigned HOST_WIDE_INT size,
3995 unsigned int align)
3997 tree type = TREE_TYPE (exp);
3998 tree link, field = 0;
3999 tree min_index = 0;
4000 /* Number of bytes output or skipped so far.
4001 In other words, current position within the constructor. */
4002 HOST_WIDE_INT total_bytes = 0;
4003 /* Nonzero means BYTE contains part of a byte, to be output. */
4004 int byte_buffer_in_use = 0;
4005 int byte = 0;
4007 gcc_assert (HOST_BITS_PER_WIDE_INT >= BITS_PER_UNIT);
4009 if (TREE_CODE (type) == RECORD_TYPE)
4010 field = TYPE_FIELDS (type);
4012 if (TREE_CODE (type) == ARRAY_TYPE
4013 && TYPE_DOMAIN (type) != 0)
4014 min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (type));
4016 /* As LINK goes through the elements of the constant,
4017 FIELD goes through the structure fields, if the constant is a structure.
4018 if the constant is a union, then we override this,
4019 by getting the field from the TREE_LIST element.
4020 But the constant could also be an array. Then FIELD is zero.
4022 There is always a maximum of one element in the chain LINK for unions
4023 (even if the initializer in a source program incorrectly contains
4024 more one). */
4025 for (link = CONSTRUCTOR_ELTS (exp);
4026 link;
4027 link = TREE_CHAIN (link),
4028 field = field ? TREE_CHAIN (field) : 0)
4030 tree val = TREE_VALUE (link);
4031 tree index = 0;
4033 /* The element in a union constructor specifies the proper field
4034 or index. */
4035 if ((TREE_CODE (type) == RECORD_TYPE || TREE_CODE (type) == UNION_TYPE
4036 || TREE_CODE (type) == QUAL_UNION_TYPE)
4037 && TREE_PURPOSE (link) != 0)
4038 field = TREE_PURPOSE (link);
4040 else if (TREE_CODE (type) == ARRAY_TYPE)
4041 index = TREE_PURPOSE (link);
4043 #ifdef ASM_COMMENT_START
4044 if (field && flag_verbose_asm)
4045 fprintf (asm_out_file, "%s %s:\n",
4046 ASM_COMMENT_START,
4047 DECL_NAME (field)
4048 ? IDENTIFIER_POINTER (DECL_NAME (field))
4049 : "<anonymous>");
4050 #endif
4052 /* Eliminate the marker that makes a cast not be an lvalue. */
4053 if (val != 0)
4054 STRIP_NOPS (val);
4056 if (index && TREE_CODE (index) == RANGE_EXPR)
4058 unsigned HOST_WIDE_INT fieldsize
4059 = int_size_in_bytes (TREE_TYPE (type));
4060 HOST_WIDE_INT lo_index = tree_low_cst (TREE_OPERAND (index, 0), 0);
4061 HOST_WIDE_INT hi_index = tree_low_cst (TREE_OPERAND (index, 1), 0);
4062 HOST_WIDE_INT index;
4063 unsigned int align2 = min_align (align, fieldsize * BITS_PER_UNIT);
4065 for (index = lo_index; index <= hi_index; index++)
4067 /* Output the element's initial value. */
4068 if (val == 0)
4069 assemble_zeros (fieldsize);
4070 else
4071 output_constant (val, fieldsize, align2);
4073 /* Count its size. */
4074 total_bytes += fieldsize;
4077 else if (field == 0 || !DECL_BIT_FIELD (field))
4079 /* An element that is not a bit-field. */
4081 unsigned HOST_WIDE_INT fieldsize;
4082 /* Since this structure is static,
4083 we know the positions are constant. */
4084 HOST_WIDE_INT pos = field ? int_byte_position (field) : 0;
4085 unsigned int align2;
4087 if (index != 0)
4088 pos = (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (val)), 1)
4089 * (tree_low_cst (index, 0) - tree_low_cst (min_index, 0)));
4091 /* Output any buffered-up bit-fields preceding this element. */
4092 if (byte_buffer_in_use)
4094 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4095 total_bytes++;
4096 byte_buffer_in_use = 0;
4099 /* Advance to offset of this element.
4100 Note no alignment needed in an array, since that is guaranteed
4101 if each element has the proper size. */
4102 if ((field != 0 || index != 0) && pos != total_bytes)
4104 assemble_zeros (pos - total_bytes);
4105 total_bytes = pos;
4108 /* Find the alignment of this element. */
4109 align2 = min_align (align, BITS_PER_UNIT * pos);
4111 /* Determine size this element should occupy. */
4112 if (field)
4114 fieldsize = 0;
4116 /* If this is an array with an unspecified upper bound,
4117 the initializer determines the size. */
4118 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
4119 but we cannot do this until the deprecated support for
4120 initializing zero-length array members is removed. */
4121 if (TREE_CODE (TREE_TYPE (field)) == ARRAY_TYPE
4122 && TYPE_DOMAIN (TREE_TYPE (field))
4123 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (field))))
4125 fieldsize = array_size_for_constructor (val);
4126 /* Given a non-empty initialization, this field had
4127 better be last. */
4128 gcc_assert (!fieldsize || !TREE_CHAIN (field));
4130 else if (DECL_SIZE_UNIT (field))
4132 /* ??? This can't be right. If the decl size overflows
4133 a host integer we will silently emit no data. */
4134 if (host_integerp (DECL_SIZE_UNIT (field), 1))
4135 fieldsize = tree_low_cst (DECL_SIZE_UNIT (field), 1);
4138 else
4139 fieldsize = int_size_in_bytes (TREE_TYPE (type));
4141 /* Output the element's initial value. */
4142 if (val == 0)
4143 assemble_zeros (fieldsize);
4144 else
4145 output_constant (val, fieldsize, align2);
4147 /* Count its size. */
4148 total_bytes += fieldsize;
4150 else if (val != 0 && TREE_CODE (val) != INTEGER_CST)
4151 error ("invalid initial value for member %qs",
4152 IDENTIFIER_POINTER (DECL_NAME (field)));
4153 else
4155 /* Element that is a bit-field. */
4157 HOST_WIDE_INT next_offset = int_bit_position (field);
4158 HOST_WIDE_INT end_offset
4159 = (next_offset + tree_low_cst (DECL_SIZE (field), 1));
4161 if (val == 0)
4162 val = integer_zero_node;
4164 /* If this field does not start in this (or, next) byte,
4165 skip some bytes. */
4166 if (next_offset / BITS_PER_UNIT != total_bytes)
4168 /* Output remnant of any bit field in previous bytes. */
4169 if (byte_buffer_in_use)
4171 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4172 total_bytes++;
4173 byte_buffer_in_use = 0;
4176 /* If still not at proper byte, advance to there. */
4177 if (next_offset / BITS_PER_UNIT != total_bytes)
4179 assemble_zeros (next_offset / BITS_PER_UNIT - total_bytes);
4180 total_bytes = next_offset / BITS_PER_UNIT;
4184 if (! byte_buffer_in_use)
4185 byte = 0;
4187 /* We must split the element into pieces that fall within
4188 separate bytes, and combine each byte with previous or
4189 following bit-fields. */
4191 /* next_offset is the offset n fbits from the beginning of
4192 the structure to the next bit of this element to be processed.
4193 end_offset is the offset of the first bit past the end of
4194 this element. */
4195 while (next_offset < end_offset)
4197 int this_time;
4198 int shift;
4199 HOST_WIDE_INT value;
4200 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
4201 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
4203 /* Advance from byte to byte
4204 within this element when necessary. */
4205 while (next_byte != total_bytes)
4207 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4208 total_bytes++;
4209 byte = 0;
4212 /* Number of bits we can process at once
4213 (all part of the same byte). */
4214 this_time = MIN (end_offset - next_offset,
4215 BITS_PER_UNIT - next_bit);
4216 if (BYTES_BIG_ENDIAN)
4218 /* On big-endian machine, take the most significant bits
4219 first (of the bits that are significant)
4220 and put them into bytes from the most significant end. */
4221 shift = end_offset - next_offset - this_time;
4223 /* Don't try to take a bunch of bits that cross
4224 the word boundary in the INTEGER_CST. We can
4225 only select bits from the LOW or HIGH part
4226 not from both. */
4227 if (shift < HOST_BITS_PER_WIDE_INT
4228 && shift + this_time > HOST_BITS_PER_WIDE_INT)
4230 this_time = shift + this_time - HOST_BITS_PER_WIDE_INT;
4231 shift = HOST_BITS_PER_WIDE_INT;
4234 /* Now get the bits from the appropriate constant word. */
4235 if (shift < HOST_BITS_PER_WIDE_INT)
4236 value = TREE_INT_CST_LOW (val);
4237 else
4239 gcc_assert (shift < 2 * HOST_BITS_PER_WIDE_INT);
4240 value = TREE_INT_CST_HIGH (val);
4241 shift -= HOST_BITS_PER_WIDE_INT;
4244 /* Get the result. This works only when:
4245 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
4246 byte |= (((value >> shift)
4247 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
4248 << (BITS_PER_UNIT - this_time - next_bit));
4250 else
4252 /* On little-endian machines,
4253 take first the least significant bits of the value
4254 and pack them starting at the least significant
4255 bits of the bytes. */
4256 shift = next_offset - int_bit_position (field);
4258 /* Don't try to take a bunch of bits that cross
4259 the word boundary in the INTEGER_CST. We can
4260 only select bits from the LOW or HIGH part
4261 not from both. */
4262 if (shift < HOST_BITS_PER_WIDE_INT
4263 && shift + this_time > HOST_BITS_PER_WIDE_INT)
4264 this_time = (HOST_BITS_PER_WIDE_INT - shift);
4266 /* Now get the bits from the appropriate constant word. */
4267 if (shift < HOST_BITS_PER_WIDE_INT)
4268 value = TREE_INT_CST_LOW (val);
4269 else
4271 gcc_assert (shift < 2 * HOST_BITS_PER_WIDE_INT);
4272 value = TREE_INT_CST_HIGH (val);
4273 shift -= HOST_BITS_PER_WIDE_INT;
4276 /* Get the result. This works only when:
4277 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
4278 byte |= (((value >> shift)
4279 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
4280 << next_bit);
4283 next_offset += this_time;
4284 byte_buffer_in_use = 1;
4289 if (byte_buffer_in_use)
4291 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4292 total_bytes++;
4295 if ((unsigned HOST_WIDE_INT)total_bytes < size)
4296 assemble_zeros (size - total_bytes);
4299 /* This TREE_LIST contains any weak symbol declarations waiting
4300 to be emitted. */
4301 static GTY(()) tree weak_decls;
4303 /* Mark DECL as weak. */
4305 static void
4306 mark_weak (tree decl)
4308 DECL_WEAK (decl) = 1;
4310 if (DECL_RTL_SET_P (decl)
4311 && MEM_P (DECL_RTL (decl))
4312 && XEXP (DECL_RTL (decl), 0)
4313 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
4314 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
4317 /* Merge weak status between NEWDECL and OLDDECL. */
4319 void
4320 merge_weak (tree newdecl, tree olddecl)
4322 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
4324 if (DECL_WEAK (newdecl) && SUPPORTS_WEAK)
4326 tree *pwd;
4327 /* We put the NEWDECL on the weak_decls list at some point
4328 and OLDDECL as well. Keep just OLDDECL on the list. */
4329 for (pwd = &weak_decls; *pwd; pwd = &TREE_CHAIN (*pwd))
4330 if (TREE_VALUE (*pwd) == newdecl)
4332 *pwd = TREE_CHAIN (*pwd);
4333 break;
4336 return;
4339 if (DECL_WEAK (newdecl))
4341 tree wd;
4343 /* NEWDECL is weak, but OLDDECL is not. */
4345 /* If we already output the OLDDECL, we're in trouble; we can't
4346 go back and make it weak. This error cannot caught in
4347 declare_weak because the NEWDECL and OLDDECL was not yet
4348 been merged; therefore, TREE_ASM_WRITTEN was not set. */
4349 if (TREE_ASM_WRITTEN (olddecl))
4350 error ("%Jweak declaration of %qD must precede definition",
4351 newdecl, newdecl);
4353 /* If we've already generated rtl referencing OLDDECL, we may
4354 have done so in a way that will not function properly with
4355 a weak symbol. */
4356 else if (TREE_USED (olddecl)
4357 && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)))
4358 warning (0, "%Jweak declaration of %qD after first use results "
4359 "in unspecified behavior", newdecl, newdecl);
4361 if (SUPPORTS_WEAK)
4363 /* We put the NEWDECL on the weak_decls list at some point.
4364 Replace it with the OLDDECL. */
4365 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
4366 if (TREE_VALUE (wd) == newdecl)
4368 TREE_VALUE (wd) = olddecl;
4369 break;
4371 /* We may not find the entry on the list. If NEWDECL is a
4372 weak alias, then we will have already called
4373 globalize_decl to remove the entry; in that case, we do
4374 not need to do anything. */
4377 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
4378 mark_weak (olddecl);
4380 else
4381 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
4382 weak. Just update NEWDECL to indicate that it's weak too. */
4383 mark_weak (newdecl);
4386 /* Declare DECL to be a weak symbol. */
4388 void
4389 declare_weak (tree decl)
4391 if (! TREE_PUBLIC (decl))
4392 error ("%Jweak declaration of %qD must be public", decl, decl);
4393 else if (TREE_CODE (decl) == FUNCTION_DECL && TREE_ASM_WRITTEN (decl))
4394 error ("%Jweak declaration of %qD must precede definition", decl, decl);
4395 else if (SUPPORTS_WEAK)
4397 if (! DECL_WEAK (decl))
4398 weak_decls = tree_cons (NULL, decl, weak_decls);
4400 else
4401 warning (0, "%Jweak declaration of %qD not supported", decl, decl);
4403 mark_weak (decl);
4406 /* Emit any pending weak declarations. */
4408 void
4409 weak_finish (void)
4411 tree t;
4413 for (t = weak_decls; t; t = TREE_CHAIN (t))
4415 tree decl = TREE_VALUE (t);
4416 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
4417 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
4418 #endif
4420 if (! TREE_USED (decl))
4421 continue;
4423 #ifdef ASM_WEAKEN_DECL
4424 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
4425 #else
4426 #ifdef ASM_WEAKEN_LABEL
4427 ASM_WEAKEN_LABEL (asm_out_file, name);
4428 #else
4429 #ifdef ASM_OUTPUT_WEAK_ALIAS
4430 warning (0, "only weak aliases are supported in this configuration");
4431 return;
4432 #endif
4433 #endif
4434 #endif
4438 /* Emit the assembly bits to indicate that DECL is globally visible. */
4440 static void
4441 globalize_decl (tree decl)
4443 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
4445 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
4446 if (DECL_WEAK (decl))
4448 tree *p, t;
4450 #ifdef ASM_WEAKEN_DECL
4451 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
4452 #else
4453 ASM_WEAKEN_LABEL (asm_out_file, name);
4454 #endif
4456 /* Remove this function from the pending weak list so that
4457 we do not emit multiple .weak directives for it. */
4458 for (p = &weak_decls; (t = *p) ; )
4460 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
4461 *p = TREE_CHAIN (t);
4462 else
4463 p = &TREE_CHAIN (t);
4465 return;
4467 #elif defined(ASM_MAKE_LABEL_LINKONCE)
4468 if (DECL_ONE_ONLY (decl))
4469 ASM_MAKE_LABEL_LINKONCE (asm_out_file, name);
4470 #endif
4472 targetm.asm_out.globalize_label (asm_out_file, name);
4475 /* We have to be able to tell cgraph about the needed-ness of the target
4476 of an alias. This requires that the decl have been defined. Aliases
4477 that precede their definition have to be queued for later processing. */
4479 typedef struct alias_pair GTY(())
4481 tree decl;
4482 tree target;
4483 } alias_pair;
4485 /* Define gc'd vector type. */
4486 DEF_VEC_O(alias_pair);
4487 DEF_VEC_ALLOC_O(alias_pair,gc);
4489 static GTY(()) VEC(alias_pair,gc) *alias_pairs;
4491 /* Given an assembly name, find the decl it is associated with. At the
4492 same time, mark it needed for cgraph. */
4494 static tree
4495 find_decl_and_mark_needed (tree decl, tree target)
4497 struct cgraph_node *fnode = NULL;
4498 struct cgraph_varpool_node *vnode = NULL;
4500 /* C++ thunk emitting code produces aliases late in the game.
4501 Avoid confusing cgraph code in that case. */
4502 if (!cgraph_global_info_ready)
4504 if (TREE_CODE (decl) == FUNCTION_DECL)
4506 fnode = cgraph_node_for_asm (target);
4507 if (fnode == NULL)
4508 vnode = cgraph_varpool_node_for_asm (target);
4510 else
4512 vnode = cgraph_varpool_node_for_asm (target);
4513 if (vnode == NULL)
4514 fnode = cgraph_node_for_asm (target);
4518 if (fnode)
4520 cgraph_mark_needed_node (fnode);
4521 return fnode->decl;
4523 else if (vnode)
4525 cgraph_varpool_mark_needed_node (vnode);
4526 return vnode->decl;
4528 else
4529 return NULL_TREE;
4532 /* Output the assembler code for a define (equate) using ASM_OUTPUT_DEF
4533 or ASM_OUTPUT_DEF_FROM_DECLS. The function defines the symbol whose
4534 tree node is DECL to have the value of the tree node TARGET. */
4536 static void
4537 do_assemble_alias (tree decl, tree target ATTRIBUTE_UNUSED)
4539 if (TREE_ASM_WRITTEN (decl))
4540 return;
4542 TREE_ASM_WRITTEN (decl) = 1;
4543 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
4545 #ifdef ASM_OUTPUT_DEF
4546 /* Make name accessible from other files, if appropriate. */
4548 if (TREE_PUBLIC (decl))
4550 globalize_decl (decl);
4551 maybe_assemble_visibility (decl);
4554 # ifdef ASM_OUTPUT_DEF_FROM_DECLS
4555 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
4556 # else
4557 ASM_OUTPUT_DEF (asm_out_file,
4558 IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)),
4559 IDENTIFIER_POINTER (target));
4560 # endif
4561 #elif defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
4563 const char *name;
4564 tree *p, t;
4566 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
4567 # ifdef ASM_WEAKEN_DECL
4568 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
4569 # else
4570 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
4571 # endif
4572 /* Remove this function from the pending weak list so that
4573 we do not emit multiple .weak directives for it. */
4574 for (p = &weak_decls; (t = *p) ; )
4575 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
4576 *p = TREE_CHAIN (t);
4577 else
4578 p = &TREE_CHAIN (t);
4580 #endif
4583 /* First pass of completing pending aliases. Make sure that cgraph knows
4584 which symbols will be required. */
4586 void
4587 finish_aliases_1 (void)
4589 unsigned i;
4590 alias_pair *p;
4592 for (i = 0; VEC_iterate (alias_pair, alias_pairs, i, p); i++)
4594 tree target_decl;
4596 target_decl = find_decl_and_mark_needed (p->decl, p->target);
4597 if (target_decl == NULL)
4598 error ("%J%qD aliased to undefined symbol %qE",
4599 p->decl, p->decl, p->target);
4600 else if (DECL_EXTERNAL (target_decl))
4601 error ("%J%qD aliased to external symbol %qE",
4602 p->decl, p->decl, p->target);
4606 /* Second pass of completing pending aliases. Emit the actual assembly.
4607 This happens at the end of compilation and thus it is assured that the
4608 target symbol has been emitted. */
4610 void
4611 finish_aliases_2 (void)
4613 unsigned i;
4614 alias_pair *p;
4616 for (i = 0; VEC_iterate (alias_pair, alias_pairs, i, p); i++)
4617 do_assemble_alias (p->decl, p->target);
4619 VEC_truncate (alias_pair, alias_pairs, 0);
4622 /* Emit an assembler directive to make the symbol for DECL an alias to
4623 the symbol for TARGET. */
4625 void
4626 assemble_alias (tree decl, tree target)
4628 tree target_decl;
4630 #if !defined (ASM_OUTPUT_DEF)
4631 # if !defined(ASM_OUTPUT_WEAK_ALIAS) && !defined (ASM_WEAKEN_DECL)
4632 error ("%Jalias definitions not supported in this configuration", decl);
4633 return;
4634 # else
4635 if (!DECL_WEAK (decl))
4637 error ("%Jonly weak aliases are supported in this configuration", decl);
4638 return;
4640 # endif
4641 #endif
4643 /* We must force creation of DECL_RTL for debug info generation, even though
4644 we don't use it here. */
4645 make_decl_rtl (decl);
4646 TREE_USED (decl) = 1;
4648 /* A quirk of the initial implementation of aliases required that the user
4649 add "extern" to all of them. Which is silly, but now historical. Do
4650 note that the symbol is in fact locally defined. */
4651 DECL_EXTERNAL (decl) = 0;
4653 /* Allow aliases to aliases. */
4654 if (TREE_CODE (decl) == FUNCTION_DECL)
4655 cgraph_node (decl)->alias = true;
4656 else
4657 cgraph_varpool_node (decl)->alias = true;
4659 /* If the target has already been emitted, we don't have to queue the
4660 alias. This saves a tad o memory. */
4661 target_decl = find_decl_and_mark_needed (decl, target);
4662 if (target_decl && TREE_ASM_WRITTEN (target_decl))
4663 do_assemble_alias (decl, target);
4664 else
4666 alias_pair *p = VEC_safe_push (alias_pair, gc, alias_pairs, NULL);
4667 p->decl = decl;
4668 p->target = target;
4672 /* Emit an assembler directive to set symbol for DECL visibility to
4673 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
4675 void
4676 default_assemble_visibility (tree decl, int vis)
4678 static const char * const visibility_types[] = {
4679 NULL, "internal", "hidden", "protected"
4682 const char *name, *type;
4684 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
4685 type = visibility_types[vis];
4687 #ifdef HAVE_GAS_HIDDEN
4688 fprintf (asm_out_file, "\t.%s\t", type);
4689 assemble_name (asm_out_file, name);
4690 fprintf (asm_out_file, "\n");
4691 #else
4692 warning (OPT_Wattributes, "visibility attribute not supported "
4693 "in this configuration; ignored");
4694 #endif
4697 /* A helper function to call assemble_visibility when needed for a decl. */
4699 static void
4700 maybe_assemble_visibility (tree decl)
4702 enum symbol_visibility vis = DECL_VISIBILITY (decl);
4704 if (vis != VISIBILITY_DEFAULT)
4705 targetm.asm_out.visibility (decl, vis);
4708 /* Returns 1 if the target configuration supports defining public symbols
4709 so that one of them will be chosen at link time instead of generating a
4710 multiply-defined symbol error, whether through the use of weak symbols or
4711 a target-specific mechanism for having duplicates discarded. */
4714 supports_one_only (void)
4716 if (SUPPORTS_ONE_ONLY)
4717 return 1;
4718 return SUPPORTS_WEAK;
4721 /* Set up DECL as a public symbol that can be defined in multiple
4722 translation units without generating a linker error. */
4724 void
4725 make_decl_one_only (tree decl)
4727 gcc_assert (TREE_CODE (decl) == VAR_DECL
4728 || TREE_CODE (decl) == FUNCTION_DECL);
4730 TREE_PUBLIC (decl) = 1;
4732 if (SUPPORTS_ONE_ONLY)
4734 #ifdef MAKE_DECL_ONE_ONLY
4735 MAKE_DECL_ONE_ONLY (decl);
4736 #endif
4737 DECL_ONE_ONLY (decl) = 1;
4739 else if (TREE_CODE (decl) == VAR_DECL
4740 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node))
4741 DECL_COMMON (decl) = 1;
4742 else
4744 gcc_assert (SUPPORTS_WEAK);
4745 DECL_WEAK (decl) = 1;
4749 void
4750 init_varasm_once (void)
4752 in_named_htab = htab_create_ggc (31, in_named_entry_hash,
4753 in_named_entry_eq, NULL);
4754 const_desc_htab = htab_create_ggc (1009, const_desc_hash,
4755 const_desc_eq, NULL);
4757 const_alias_set = new_alias_set ();
4760 static enum tls_model
4761 decl_tls_model (tree decl)
4763 enum tls_model kind;
4764 tree attr = lookup_attribute ("tls_model", DECL_ATTRIBUTES (decl));
4765 bool is_local;
4767 if (attr)
4769 attr = TREE_VALUE (TREE_VALUE (attr));
4770 gcc_assert (TREE_CODE (attr) == STRING_CST);
4772 if (!strcmp (TREE_STRING_POINTER (attr), "local-exec"))
4773 kind = TLS_MODEL_LOCAL_EXEC;
4774 else if (!strcmp (TREE_STRING_POINTER (attr), "initial-exec"))
4775 kind = TLS_MODEL_INITIAL_EXEC;
4776 else if (!strcmp (TREE_STRING_POINTER (attr), "local-dynamic"))
4777 kind = optimize ? TLS_MODEL_LOCAL_DYNAMIC : TLS_MODEL_GLOBAL_DYNAMIC;
4778 else if (!strcmp (TREE_STRING_POINTER (attr), "global-dynamic"))
4779 kind = TLS_MODEL_GLOBAL_DYNAMIC;
4780 else
4781 gcc_unreachable ();
4782 return kind;
4785 is_local = targetm.binds_local_p (decl);
4786 if (!flag_shlib)
4788 if (is_local)
4789 kind = TLS_MODEL_LOCAL_EXEC;
4790 else
4791 kind = TLS_MODEL_INITIAL_EXEC;
4793 /* Local dynamic is inefficient when we're not combining the
4794 parts of the address. */
4795 else if (optimize && is_local)
4796 kind = TLS_MODEL_LOCAL_DYNAMIC;
4797 else
4798 kind = TLS_MODEL_GLOBAL_DYNAMIC;
4799 if (kind < flag_tls_default)
4800 kind = flag_tls_default;
4802 return kind;
4805 /* Select a set of attributes for section NAME based on the properties
4806 of DECL and whether or not RELOC indicates that DECL's initializer
4807 might contain runtime relocations.
4809 We make the section read-only and executable for a function decl,
4810 read-only for a const data decl, and writable for a non-const data decl. */
4812 unsigned int
4813 default_section_type_flags (tree decl, const char *name, int reloc)
4815 return default_section_type_flags_1 (decl, name, reloc, flag_pic);
4818 unsigned int
4819 default_section_type_flags_1 (tree decl, const char *name, int reloc,
4820 int shlib)
4822 unsigned int flags;
4824 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
4825 flags = SECTION_CODE;
4826 else if (decl && decl_readonly_section_1 (decl, reloc, shlib))
4827 flags = 0;
4828 else if (current_function_decl
4829 && cfun
4830 && cfun->unlikely_text_section_name
4831 && strcmp (name, cfun->unlikely_text_section_name) == 0)
4832 flags = SECTION_CODE;
4833 else if (!decl
4834 && (!current_function_decl || !cfun)
4835 && strcmp (name, UNLIKELY_EXECUTED_TEXT_SECTION_NAME) == 0)
4836 flags = SECTION_CODE;
4837 else
4838 flags = SECTION_WRITE;
4840 if (decl && DECL_ONE_ONLY (decl))
4841 flags |= SECTION_LINKONCE;
4843 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl))
4844 flags |= SECTION_TLS | SECTION_WRITE;
4846 if (strcmp (name, ".bss") == 0
4847 || strncmp (name, ".bss.", 5) == 0
4848 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
4849 || strcmp (name, ".sbss") == 0
4850 || strncmp (name, ".sbss.", 6) == 0
4851 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0)
4852 flags |= SECTION_BSS;
4854 if (strcmp (name, ".tdata") == 0
4855 || strncmp (name, ".tdata.", 7) == 0
4856 || strncmp (name, ".gnu.linkonce.td.", 17) == 0)
4857 flags |= SECTION_TLS;
4859 if (strcmp (name, ".tbss") == 0
4860 || strncmp (name, ".tbss.", 6) == 0
4861 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
4862 flags |= SECTION_TLS | SECTION_BSS;
4864 /* These three sections have special ELF types. They are neither
4865 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
4866 want to print a section type (@progbits or @nobits). If someone
4867 is silly enough to emit code or TLS variables to one of these
4868 sections, then don't handle them specially. */
4869 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
4870 && (strcmp (name, ".init_array") == 0
4871 || strcmp (name, ".fini_array") == 0
4872 || strcmp (name, ".preinit_array") == 0))
4873 flags |= SECTION_NOTYPE;
4875 return flags;
4878 /* Output assembly to switch to section NAME with attribute FLAGS.
4879 Four variants for common object file formats. */
4881 void
4882 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
4883 unsigned int flags ATTRIBUTE_UNUSED,
4884 tree decl ATTRIBUTE_UNUSED)
4886 /* Some object formats don't support named sections at all. The
4887 front-end should already have flagged this as an error. */
4888 gcc_unreachable ();
4891 void
4892 default_elf_asm_named_section (const char *name, unsigned int flags,
4893 tree decl ATTRIBUTE_UNUSED)
4895 char flagchars[10], *f = flagchars;
4897 /* If we have already declared this section, we can use an
4898 abbreviated form to switch back to it -- unless this section is
4899 part of a COMDAT groups, in which case GAS requires the full
4900 declaration every time. */
4901 if (!(HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
4902 && ! named_section_first_declaration (name))
4904 fprintf (asm_out_file, "\t.section\t%s\n", name);
4905 return;
4908 if (!(flags & SECTION_DEBUG))
4909 *f++ = 'a';
4910 if (flags & SECTION_WRITE)
4911 *f++ = 'w';
4912 if (flags & SECTION_CODE)
4913 *f++ = 'x';
4914 if (flags & SECTION_SMALL)
4915 *f++ = 's';
4916 if (flags & SECTION_MERGE)
4917 *f++ = 'M';
4918 if (flags & SECTION_STRINGS)
4919 *f++ = 'S';
4920 if (flags & SECTION_TLS)
4921 *f++ = 'T';
4922 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
4923 *f++ = 'G';
4924 *f = '\0';
4926 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
4928 if (!(flags & SECTION_NOTYPE))
4930 const char *type;
4931 const char *format;
4933 if (flags & SECTION_BSS)
4934 type = "nobits";
4935 else
4936 type = "progbits";
4938 format = ",@%s";
4939 #ifdef ASM_COMMENT_START
4940 /* On platforms that use "@" as the assembly comment character,
4941 use "%" instead. */
4942 if (strcmp (ASM_COMMENT_START, "@") == 0)
4943 format = ",%%%s";
4944 #endif
4945 fprintf (asm_out_file, format, type);
4947 if (flags & SECTION_ENTSIZE)
4948 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
4949 if (HAVE_COMDAT_GROUP && (flags & SECTION_LINKONCE))
4950 fprintf (asm_out_file, ",%s,comdat",
4951 lang_hooks.decls.comdat_group (decl));
4954 putc ('\n', asm_out_file);
4957 void
4958 default_coff_asm_named_section (const char *name, unsigned int flags,
4959 tree decl ATTRIBUTE_UNUSED)
4961 char flagchars[8], *f = flagchars;
4963 if (flags & SECTION_WRITE)
4964 *f++ = 'w';
4965 if (flags & SECTION_CODE)
4966 *f++ = 'x';
4967 *f = '\0';
4969 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
4972 void
4973 default_pe_asm_named_section (const char *name, unsigned int flags,
4974 tree decl)
4976 default_coff_asm_named_section (name, flags, decl);
4978 if (flags & SECTION_LINKONCE)
4980 /* Functions may have been compiled at various levels of
4981 optimization so we can't use `same_size' here.
4982 Instead, have the linker pick one. */
4983 fprintf (asm_out_file, "\t.linkonce %s\n",
4984 (flags & SECTION_CODE ? "discard" : "same_size"));
4988 /* The lame default section selector. */
4990 void
4991 default_select_section (tree decl, int reloc,
4992 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
4994 bool readonly = false;
4996 if (DECL_P (decl))
4998 if (decl_readonly_section (decl, reloc))
4999 readonly = true;
5001 else if (TREE_CODE (decl) == CONSTRUCTOR)
5003 if (! ((flag_pic && reloc)
5004 || !TREE_READONLY (decl)
5005 || TREE_SIDE_EFFECTS (decl)
5006 || !TREE_CONSTANT (decl)))
5007 readonly = true;
5009 else if (TREE_CODE (decl) == STRING_CST)
5010 readonly = true;
5011 else if (! (flag_pic && reloc))
5012 readonly = true;
5014 if (readonly)
5015 readonly_data_section ();
5016 else
5017 data_section ();
5020 /* A helper function for default_elf_select_section and
5021 default_elf_unique_section. Categorizes the DECL. */
5023 enum section_category
5025 SECCAT_TEXT,
5027 SECCAT_RODATA,
5028 SECCAT_RODATA_MERGE_STR,
5029 SECCAT_RODATA_MERGE_STR_INIT,
5030 SECCAT_RODATA_MERGE_CONST,
5031 SECCAT_SRODATA,
5033 SECCAT_DATA,
5035 /* To optimize loading of shared programs, define following subsections
5036 of data section:
5037 _REL Contains data that has relocations, so they get grouped
5038 together and dynamic linker will visit fewer pages in memory.
5039 _RO Contains data that is otherwise read-only. This is useful
5040 with prelinking as most relocations won't be dynamically
5041 linked and thus stay read only.
5042 _LOCAL Marks data containing relocations only to local objects.
5043 These relocations will get fully resolved by prelinking. */
5044 SECCAT_DATA_REL,
5045 SECCAT_DATA_REL_LOCAL,
5046 SECCAT_DATA_REL_RO,
5047 SECCAT_DATA_REL_RO_LOCAL,
5049 SECCAT_SDATA,
5050 SECCAT_TDATA,
5052 SECCAT_BSS,
5053 SECCAT_SBSS,
5054 SECCAT_TBSS
5057 static enum section_category
5058 categorize_decl_for_section (tree, int, int);
5060 static enum section_category
5061 categorize_decl_for_section (tree decl, int reloc, int shlib)
5063 enum section_category ret;
5065 if (TREE_CODE (decl) == FUNCTION_DECL)
5066 return SECCAT_TEXT;
5067 else if (TREE_CODE (decl) == STRING_CST)
5069 if (flag_mudflap) /* or !flag_merge_constants */
5070 return SECCAT_RODATA;
5071 else
5072 return SECCAT_RODATA_MERGE_STR;
5074 else if (TREE_CODE (decl) == VAR_DECL)
5076 if (DECL_INITIAL (decl) == NULL
5077 || DECL_INITIAL (decl) == error_mark_node
5078 || (flag_zero_initialized_in_bss
5079 /* Leave constant zeroes in .rodata so they can be shared. */
5080 && !TREE_READONLY (decl)
5081 && initializer_zerop (DECL_INITIAL (decl))))
5082 ret = SECCAT_BSS;
5083 else if (! TREE_READONLY (decl)
5084 || TREE_SIDE_EFFECTS (decl)
5085 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
5087 if (shlib && (reloc & 2))
5088 ret = SECCAT_DATA_REL;
5089 else if (shlib && reloc)
5090 ret = SECCAT_DATA_REL_LOCAL;
5091 else
5092 ret = SECCAT_DATA;
5094 else if (shlib && (reloc & 2))
5095 ret = SECCAT_DATA_REL_RO;
5096 else if (shlib && reloc)
5097 ret = SECCAT_DATA_REL_RO_LOCAL;
5098 else if (reloc || flag_merge_constants < 2)
5099 /* C and C++ don't allow different variables to share the same
5100 location. -fmerge-all-constants allows even that (at the
5101 expense of not conforming). */
5102 ret = SECCAT_RODATA;
5103 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
5104 ret = SECCAT_RODATA_MERGE_STR_INIT;
5105 else
5106 ret = SECCAT_RODATA_MERGE_CONST;
5108 else if (TREE_CODE (decl) == CONSTRUCTOR)
5110 if ((shlib && reloc)
5111 || TREE_SIDE_EFFECTS (decl)
5112 || ! TREE_CONSTANT (decl))
5113 ret = SECCAT_DATA;
5114 else
5115 ret = SECCAT_RODATA;
5117 else
5118 ret = SECCAT_RODATA;
5120 /* There are no read-only thread-local sections. */
5121 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl))
5123 /* Note that this would be *just* SECCAT_BSS, except that there's
5124 no concept of a read-only thread-local-data section. */
5125 if (ret == SECCAT_BSS
5126 || (flag_zero_initialized_in_bss
5127 && initializer_zerop (DECL_INITIAL (decl))))
5128 ret = SECCAT_TBSS;
5129 else
5130 ret = SECCAT_TDATA;
5133 /* If the target uses small data sections, select it. */
5134 else if (targetm.in_small_data_p (decl))
5136 if (ret == SECCAT_BSS)
5137 ret = SECCAT_SBSS;
5138 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
5139 ret = SECCAT_SRODATA;
5140 else
5141 ret = SECCAT_SDATA;
5144 return ret;
5147 bool
5148 decl_readonly_section (tree decl, int reloc)
5150 return decl_readonly_section_1 (decl, reloc, flag_pic);
5153 bool
5154 decl_readonly_section_1 (tree decl, int reloc, int shlib)
5156 switch (categorize_decl_for_section (decl, reloc, shlib))
5158 case SECCAT_RODATA:
5159 case SECCAT_RODATA_MERGE_STR:
5160 case SECCAT_RODATA_MERGE_STR_INIT:
5161 case SECCAT_RODATA_MERGE_CONST:
5162 case SECCAT_SRODATA:
5163 return true;
5164 break;
5165 default:
5166 return false;
5167 break;
5171 /* Select a section based on the above categorization. */
5173 void
5174 default_elf_select_section (tree decl, int reloc,
5175 unsigned HOST_WIDE_INT align)
5177 default_elf_select_section_1 (decl, reloc, align, flag_pic);
5180 void
5181 default_elf_select_section_1 (tree decl, int reloc,
5182 unsigned HOST_WIDE_INT align, int shlib)
5184 const char *sname;
5185 switch (categorize_decl_for_section (decl, reloc, shlib))
5187 case SECCAT_TEXT:
5188 /* We're not supposed to be called on FUNCTION_DECLs. */
5189 gcc_unreachable ();
5190 case SECCAT_RODATA:
5191 readonly_data_section ();
5192 return;
5193 case SECCAT_RODATA_MERGE_STR:
5194 mergeable_string_section (decl, align, 0);
5195 return;
5196 case SECCAT_RODATA_MERGE_STR_INIT:
5197 mergeable_string_section (DECL_INITIAL (decl), align, 0);
5198 return;
5199 case SECCAT_RODATA_MERGE_CONST:
5200 mergeable_constant_section (DECL_MODE (decl), align, 0);
5201 return;
5202 case SECCAT_SRODATA:
5203 sname = ".sdata2";
5204 break;
5205 case SECCAT_DATA:
5206 data_section ();
5207 return;
5208 case SECCAT_DATA_REL:
5209 sname = ".data.rel";
5210 break;
5211 case SECCAT_DATA_REL_LOCAL:
5212 sname = ".data.rel.local";
5213 break;
5214 case SECCAT_DATA_REL_RO:
5215 sname = ".data.rel.ro";
5216 break;
5217 case SECCAT_DATA_REL_RO_LOCAL:
5218 sname = ".data.rel.ro.local";
5219 break;
5220 case SECCAT_SDATA:
5221 sname = ".sdata";
5222 break;
5223 case SECCAT_TDATA:
5224 sname = ".tdata";
5225 break;
5226 case SECCAT_BSS:
5227 #ifdef BSS_SECTION_ASM_OP
5228 bss_section ();
5229 return;
5230 #else
5231 sname = ".bss";
5232 break;
5233 #endif
5234 case SECCAT_SBSS:
5235 sname = ".sbss";
5236 break;
5237 case SECCAT_TBSS:
5238 sname = ".tbss";
5239 break;
5240 default:
5241 gcc_unreachable ();
5244 if (!DECL_P (decl))
5245 decl = NULL_TREE;
5246 named_section (decl, sname, reloc);
5249 /* Construct a unique section name based on the decl name and the
5250 categorization performed above. */
5252 void
5253 default_unique_section (tree decl, int reloc)
5255 default_unique_section_1 (decl, reloc, flag_pic);
5258 void
5259 default_unique_section_1 (tree decl, int reloc, int shlib)
5261 /* We only need to use .gnu.linkonce if we don't have COMDAT groups. */
5262 bool one_only = DECL_ONE_ONLY (decl) && !HAVE_COMDAT_GROUP;
5263 const char *prefix, *name;
5264 size_t nlen, plen;
5265 char *string;
5267 switch (categorize_decl_for_section (decl, reloc, shlib))
5269 case SECCAT_TEXT:
5270 prefix = one_only ? ".gnu.linkonce.t." : ".text.";
5271 break;
5272 case SECCAT_RODATA:
5273 case SECCAT_RODATA_MERGE_STR:
5274 case SECCAT_RODATA_MERGE_STR_INIT:
5275 case SECCAT_RODATA_MERGE_CONST:
5276 prefix = one_only ? ".gnu.linkonce.r." : ".rodata.";
5277 break;
5278 case SECCAT_SRODATA:
5279 prefix = one_only ? ".gnu.linkonce.s2." : ".sdata2.";
5280 break;
5281 case SECCAT_DATA:
5282 case SECCAT_DATA_REL:
5283 case SECCAT_DATA_REL_LOCAL:
5284 case SECCAT_DATA_REL_RO:
5285 case SECCAT_DATA_REL_RO_LOCAL:
5286 prefix = one_only ? ".gnu.linkonce.d." : ".data.";
5287 break;
5288 case SECCAT_SDATA:
5289 prefix = one_only ? ".gnu.linkonce.s." : ".sdata.";
5290 break;
5291 case SECCAT_BSS:
5292 prefix = one_only ? ".gnu.linkonce.b." : ".bss.";
5293 break;
5294 case SECCAT_SBSS:
5295 prefix = one_only ? ".gnu.linkonce.sb." : ".sbss.";
5296 break;
5297 case SECCAT_TDATA:
5298 prefix = one_only ? ".gnu.linkonce.td." : ".tdata.";
5299 break;
5300 case SECCAT_TBSS:
5301 prefix = one_only ? ".gnu.linkonce.tb." : ".tbss.";
5302 break;
5303 default:
5304 gcc_unreachable ();
5306 plen = strlen (prefix);
5308 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5309 name = targetm.strip_name_encoding (name);
5310 nlen = strlen (name);
5312 string = alloca (nlen + plen + 1);
5313 memcpy (string, prefix, plen);
5314 memcpy (string + plen, name, nlen + 1);
5316 DECL_SECTION_NAME (decl) = build_string (nlen + plen, string);
5319 void
5320 default_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
5321 rtx x,
5322 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
5324 if (flag_pic)
5325 switch (GET_CODE (x))
5327 case CONST:
5328 case SYMBOL_REF:
5329 case LABEL_REF:
5330 data_section ();
5331 return;
5333 default:
5334 break;
5337 readonly_data_section ();
5340 void
5341 default_elf_select_rtx_section (enum machine_mode mode, rtx x,
5342 unsigned HOST_WIDE_INT align)
5344 /* ??? Handle small data here somehow. */
5346 if (flag_pic)
5347 switch (GET_CODE (x))
5349 case CONST:
5350 case SYMBOL_REF:
5351 named_section (NULL_TREE, ".data.rel.ro", 3);
5352 return;
5354 case LABEL_REF:
5355 named_section (NULL_TREE, ".data.rel.ro.local", 1);
5356 return;
5358 default:
5359 break;
5362 mergeable_constant_section (mode, align, 0);
5365 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
5367 void
5368 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
5370 rtx symbol;
5371 int flags;
5373 /* Careful not to prod global register variables. */
5374 if (!MEM_P (rtl))
5375 return;
5376 symbol = XEXP (rtl, 0);
5377 if (GET_CODE (symbol) != SYMBOL_REF)
5378 return;
5380 flags = 0;
5381 if (TREE_CODE (decl) == FUNCTION_DECL)
5382 flags |= SYMBOL_FLAG_FUNCTION;
5383 if (targetm.binds_local_p (decl))
5384 flags |= SYMBOL_FLAG_LOCAL;
5385 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl))
5386 flags |= decl_tls_model (decl) << SYMBOL_FLAG_TLS_SHIFT;
5387 else if (targetm.in_small_data_p (decl))
5388 flags |= SYMBOL_FLAG_SMALL;
5389 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
5390 being PUBLIC, the thing *must* be defined in this translation unit.
5391 Prevent this buglet from being propagated into rtl code as well. */
5392 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
5393 flags |= SYMBOL_FLAG_EXTERNAL;
5395 SYMBOL_REF_FLAGS (symbol) = flags;
5398 /* By default, we do nothing for encode_section_info, so we need not
5399 do anything but discard the '*' marker. */
5401 const char *
5402 default_strip_name_encoding (const char *str)
5404 return str + (*str == '*');
5407 /* Assume ELF-ish defaults, since that's pretty much the most liberal
5408 wrt cross-module name binding. */
5410 bool
5411 default_binds_local_p (tree exp)
5413 return default_binds_local_p_1 (exp, flag_shlib);
5416 bool
5417 default_binds_local_p_1 (tree exp, int shlib)
5419 bool local_p;
5421 /* A non-decl is an entry in the constant pool. */
5422 if (!DECL_P (exp))
5423 local_p = true;
5424 /* Static variables are always local. */
5425 else if (! TREE_PUBLIC (exp))
5426 local_p = true;
5427 /* A variable is local if the user explicitly tells us so. */
5428 else if (DECL_VISIBILITY_SPECIFIED (exp) && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
5429 local_p = true;
5430 /* Otherwise, variables defined outside this object may not be local. */
5431 else if (DECL_EXTERNAL (exp))
5432 local_p = false;
5433 /* Linkonce and weak data are never local. */
5434 else if (DECL_ONE_ONLY (exp) || DECL_WEAK (exp))
5435 local_p = false;
5436 /* If none of the above and visibility is not default, make local. */
5437 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
5438 local_p = true;
5439 /* If PIC, then assume that any global name can be overridden by
5440 symbols resolved from other modules. */
5441 else if (shlib)
5442 local_p = false;
5443 /* Uninitialized COMMON variable may be unified with symbols
5444 resolved from other modules. */
5445 else if (DECL_COMMON (exp)
5446 && (DECL_INITIAL (exp) == NULL
5447 || DECL_INITIAL (exp) == error_mark_node))
5448 local_p = false;
5449 /* Otherwise we're left with initialized (or non-common) global data
5450 which is of necessity defined locally. */
5451 else
5452 local_p = true;
5454 return local_p;
5457 /* Determine whether or not a pointer mode is valid. Assume defaults
5458 of ptr_mode or Pmode - can be overridden. */
5459 bool
5460 default_valid_pointer_mode (enum machine_mode mode)
5462 return (mode == ptr_mode || mode == Pmode);
5465 /* Default function to output code that will globalize a label. A
5466 target must define GLOBAL_ASM_OP or provide its own function to
5467 globalize a label. */
5468 #ifdef GLOBAL_ASM_OP
5469 void
5470 default_globalize_label (FILE * stream, const char *name)
5472 fputs (GLOBAL_ASM_OP, stream);
5473 assemble_name (stream, name);
5474 putc ('\n', stream);
5476 #endif /* GLOBAL_ASM_OP */
5478 /* Default function to output a label for unwind information. The
5479 default is to do nothing. A target that needs nonlocal labels for
5480 unwind information must provide its own function to do this. */
5481 void
5482 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
5483 tree decl ATTRIBUTE_UNUSED,
5484 int for_eh ATTRIBUTE_UNUSED,
5485 int empty ATTRIBUTE_UNUSED)
5489 /* This is how to output an internal numbered label where PREFIX is
5490 the class of label and LABELNO is the number within the class. */
5492 void
5493 default_internal_label (FILE *stream, const char *prefix,
5494 unsigned long labelno)
5496 char *const buf = alloca (40 + strlen (prefix));
5497 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
5498 ASM_OUTPUT_INTERNAL_LABEL (stream, buf);
5501 /* This is the default behavior at the beginning of a file. It's
5502 controlled by two other target-hook toggles. */
5503 void
5504 default_file_start (void)
5506 if (targetm.file_start_app_off && !flag_verbose_asm)
5507 fputs (ASM_APP_OFF, asm_out_file);
5509 if (targetm.file_start_file_directive)
5510 output_file_directive (asm_out_file, main_input_filename);
5513 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
5514 which emits a special section directive used to indicate whether or
5515 not this object file needs an executable stack. This is primarily
5516 a GNU extension to ELF but could be used on other targets. */
5518 int trampolines_created;
5520 void
5521 file_end_indicate_exec_stack (void)
5523 unsigned int flags = SECTION_DEBUG;
5524 if (trampolines_created)
5525 flags |= SECTION_CODE;
5527 named_section_flags (".note.GNU-stack", flags);
5530 #include "gt-varasm.h"