* config/arm/arm.md (addsi3_cbranch_scratch): Correct constraints.
[official-gcc.git] / gcc / varasm.c
blob8a607f5b9831d0f9361a7c79900343ef6c67b5b5
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 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
10 version.
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
20 02111-1307, USA. */
23 /* This file handles generation of all the assembler code
24 *except* the instructions of a function.
25 This includes declarations of variables and their initial values.
27 We also output the assembler code for constants stored in memory
28 and are responsible for combining constants with the same value. */
30 #include "config.h"
31 #include "system.h"
32 #include "coretypes.h"
33 #include "tm.h"
34 #include "rtl.h"
35 #include "tree.h"
36 #include "flags.h"
37 #include "function.h"
38 #include "expr.h"
39 #include "hard-reg-set.h"
40 #include "regs.h"
41 #include "real.h"
42 #include "output.h"
43 #include "toplev.h"
44 #include "hashtab.h"
45 #include "c-pragma.h"
46 #include "ggc.h"
47 #include "langhooks.h"
48 #include "tm_p.h"
49 #include "debug.h"
50 #include "target.h"
51 #include "tree-mudflap.h"
52 #include "cgraph.h"
53 #include "cfglayout.h"
55 #ifdef XCOFF_DEBUGGING_INFO
56 #include "xcoffout.h" /* Needed for external data
57 declarations for e.g. AIX 4.x. */
58 #endif
60 #ifndef ASM_STABS_OP
61 #define ASM_STABS_OP "\t.stabs\t"
62 #endif
64 /* The (assembler) name of the first globally-visible object output. */
65 const char *first_global_object_name;
66 const char *weak_global_object_name;
68 struct addr_const;
69 struct constant_descriptor_rtx;
70 struct rtx_constant_pool;
72 struct varasm_status GTY(())
74 /* If we're using a per-function constant pool, this is it. */
75 struct rtx_constant_pool *pool;
77 /* Number of tree-constants deferred during the expansion of this
78 function. */
79 unsigned int deferred_constants;
82 #define n_deferred_constants (cfun->varasm->deferred_constants)
84 /* Number for making the label on the next
85 constant that is stored in memory. */
87 static GTY(()) int const_labelno;
89 /* Carry information from ASM_DECLARE_OBJECT_NAME
90 to ASM_FINISH_DECLARE_OBJECT. */
92 int size_directive_output;
94 /* The last decl for which assemble_variable was called,
95 if it did ASM_DECLARE_OBJECT_NAME.
96 If the last call to assemble_variable didn't do that,
97 this holds 0. */
99 tree last_assemble_variable_decl;
101 /* The following global variable indicates if the section label for the
102 "cold" section of code has been output yet to the assembler. The
103 label is useful when running gdb. This is part of the optimization that
104 partitions hot and cold basic blocks into separate sections of the .o
105 file. */
107 static bool unlikely_section_label_printed = false;
109 /* The following global variable indicates the label name to be put at
110 the start of the first cold section within each function, when
111 partitioning basic blocks into hot and cold sections. */
113 static char *unlikely_section_label = NULL;
115 /* The following global variable indicates the section name to be used
116 for the current cold section, when partitioning hot and cold basic
117 blocks into separate sections. */
119 static char *unlikely_text_section_name = NULL;
121 /* We give all constants their own alias set. Perhaps redundant with
122 MEM_READONLY_P, but pre-dates it. */
124 static HOST_WIDE_INT const_alias_set;
126 static const char *strip_reg_name (const char *);
127 static int contains_pointers_p (tree);
128 #ifdef ASM_OUTPUT_EXTERNAL
129 static bool incorporeal_function_p (tree);
130 #endif
131 static void decode_addr_const (tree, struct addr_const *);
132 static hashval_t const_desc_hash (const void *);
133 static int const_desc_eq (const void *, const void *);
134 static hashval_t const_hash_1 (const tree);
135 static int compare_constant (const tree, const tree);
136 static tree copy_constant (tree);
137 static void output_constant_def_contents (rtx);
138 static void output_addressed_constants (tree);
139 static unsigned HOST_WIDE_INT array_size_for_constructor (tree);
140 static unsigned min_align (unsigned, unsigned);
141 static void output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int);
142 static void globalize_decl (tree);
143 static void maybe_assemble_visibility (tree);
144 static int in_named_entry_eq (const void *, const void *);
145 static hashval_t in_named_entry_hash (const void *);
146 #ifdef BSS_SECTION_ASM_OP
147 #ifdef ASM_OUTPUT_BSS
148 static void asm_output_bss (FILE *, tree, const char *,
149 unsigned HOST_WIDE_INT, unsigned HOST_WIDE_INT);
150 #endif
151 #ifdef ASM_OUTPUT_ALIGNED_BSS
152 static void asm_output_aligned_bss (FILE *, tree, const char *,
153 unsigned HOST_WIDE_INT, int)
154 ATTRIBUTE_UNUSED;
155 #endif
156 #endif /* BSS_SECTION_ASM_OP */
157 static bool asm_emit_uninitialised (tree, const char*,
158 unsigned HOST_WIDE_INT,
159 unsigned HOST_WIDE_INT);
160 static void mark_weak (tree);
162 enum in_section { no_section, in_text, in_unlikely_executed_text, in_data,
163 in_named
164 #ifdef BSS_SECTION_ASM_OP
165 , in_bss
166 #endif
167 #ifdef CTORS_SECTION_ASM_OP
168 , in_ctors
169 #endif
170 #ifdef DTORS_SECTION_ASM_OP
171 , in_dtors
172 #endif
173 #ifdef READONLY_DATA_SECTION_ASM_OP
174 , in_readonly_data
175 #endif
176 #ifdef EXTRA_SECTIONS
177 , EXTRA_SECTIONS
178 #endif
180 static GTY(()) enum in_section in_section = no_section;
182 /* Return a nonzero value if DECL has a section attribute. */
183 #ifndef IN_NAMED_SECTION
184 #define IN_NAMED_SECTION(DECL) \
185 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \
186 && DECL_SECTION_NAME (DECL) != NULL_TREE)
187 #endif
189 /* Text of section name when in_section == in_named. */
190 static GTY(()) const char *in_named_name;
192 /* Hash table of flags that have been used for a particular named section. */
194 struct in_named_entry GTY(())
196 const char *name;
197 unsigned int flags;
198 bool declared;
201 static GTY((param_is (struct in_named_entry))) htab_t in_named_htab;
203 /* Define functions like text_section for any extra sections. */
204 #ifdef EXTRA_SECTION_FUNCTIONS
205 EXTRA_SECTION_FUNCTIONS
206 #endif
208 /* Tell assembler to switch to text section. */
210 void
211 text_section (void)
213 if (in_section != in_text)
215 in_section = in_text;
216 fprintf (asm_out_file, "%s\n", TEXT_SECTION_ASM_OP);
220 /* Tell assembler to switch to unlikely-to-be-executed text section. */
222 void
223 unlikely_text_section (void)
225 const char *name;
226 int len;
228 if (! unlikely_text_section_name)
230 if (DECL_SECTION_NAME (current_function_decl)
231 && (strcmp (TREE_STRING_POINTER (DECL_SECTION_NAME
232 (current_function_decl)),
233 HOT_TEXT_SECTION_NAME) != 0)
234 && (strcmp (TREE_STRING_POINTER (DECL_SECTION_NAME
235 (current_function_decl)),
236 UNLIKELY_EXECUTED_TEXT_SECTION_NAME) != 0))
238 name = TREE_STRING_POINTER (DECL_SECTION_NAME
239 (current_function_decl));
240 len = strlen (name);
241 unlikely_text_section_name = xmalloc ((len + 10) * sizeof (char));
242 strcpy (unlikely_text_section_name, name);
243 strcat (unlikely_text_section_name, "_unlikely");
245 else
247 len = strlen (UNLIKELY_EXECUTED_TEXT_SECTION_NAME);
248 unlikely_text_section_name = xmalloc (len+1 * sizeof (char));
249 strcpy (unlikely_text_section_name,
250 UNLIKELY_EXECUTED_TEXT_SECTION_NAME);
254 if ((in_section != in_unlikely_executed_text)
255 && (in_section != in_named
256 || strcmp (in_named_name, unlikely_text_section_name) != 0))
258 named_section (NULL_TREE, unlikely_text_section_name, 0);
259 in_section = in_unlikely_executed_text;
261 if (!unlikely_section_label_printed)
263 ASM_OUTPUT_LABEL (asm_out_file, unlikely_section_label);
264 unlikely_section_label_printed = true;
269 /* Tell assembler to switch to data section. */
271 void
272 data_section (void)
274 if (in_section != in_data)
276 in_section = in_data;
277 fprintf (asm_out_file, "%s\n", DATA_SECTION_ASM_OP);
281 /* Tell assembler to switch to read-only data section. This is normally
282 the text section. */
284 void
285 readonly_data_section (void)
287 #ifdef READONLY_DATA_SECTION
288 READONLY_DATA_SECTION (); /* Note this can call data_section. */
289 #else
290 #ifdef READONLY_DATA_SECTION_ASM_OP
291 if (in_section != in_readonly_data)
293 in_section = in_readonly_data;
294 fputs (READONLY_DATA_SECTION_ASM_OP, asm_out_file);
295 fputc ('\n', asm_out_file);
297 #else
298 text_section ();
299 #endif
300 #endif
303 /* Determine if we're in the text section. */
306 in_text_section (void)
308 return in_section == in_text;
311 /* Determine if we're in the unlikely-to-be-executed text section. */
314 in_unlikely_text_section (void)
316 bool ret_val;
318 ret_val = ((in_section == in_unlikely_executed_text)
319 || (in_section == in_named
320 && unlikely_text_section_name
321 && strcmp (in_named_name, unlikely_text_section_name) == 0));
323 return ret_val;
326 /* Determine if we're in the data section. */
329 in_data_section (void)
331 return in_section == in_data;
334 /* Helper routines for maintaining in_named_htab. */
336 static int
337 in_named_entry_eq (const void *p1, const void *p2)
339 const struct in_named_entry *old = p1;
340 const char *new = p2;
342 return strcmp (old->name, new) == 0;
345 static hashval_t
346 in_named_entry_hash (const void *p)
348 const struct in_named_entry *old = p;
349 return htab_hash_string (old->name);
352 /* If SECTION has been seen before as a named section, return the flags
353 that were used. Otherwise, return 0. Note, that 0 is a perfectly valid
354 set of flags for a section to have, so 0 does not mean that the section
355 has not been seen. */
357 unsigned int
358 get_named_section_flags (const char *section)
360 struct in_named_entry **slot;
362 slot = (struct in_named_entry **)
363 htab_find_slot_with_hash (in_named_htab, section,
364 htab_hash_string (section), NO_INSERT);
366 return slot ? (*slot)->flags : 0;
369 /* Returns true if the section has been declared before. Sets internal
370 flag on this section in in_named_hash so subsequent calls on this
371 section will return false. */
373 bool
374 named_section_first_declaration (const char *name)
376 struct in_named_entry **slot;
378 slot = (struct in_named_entry **)
379 htab_find_slot_with_hash (in_named_htab, name,
380 htab_hash_string (name), NO_INSERT);
381 if (! (*slot)->declared)
383 (*slot)->declared = true;
384 return true;
386 else
388 return false;
393 /* Record FLAGS for SECTION. If SECTION was previously recorded with a
394 different set of flags, return false. */
396 bool
397 set_named_section_flags (const char *section, unsigned int flags)
399 struct in_named_entry **slot, *entry;
401 slot = (struct in_named_entry **)
402 htab_find_slot_with_hash (in_named_htab, section,
403 htab_hash_string (section), INSERT);
404 entry = *slot;
406 if (!entry)
408 entry = ggc_alloc (sizeof (*entry));
409 *slot = entry;
410 entry->name = ggc_strdup (section);
411 entry->flags = flags;
412 entry->declared = false;
414 else if (entry->flags != flags)
415 return false;
417 return true;
420 /* Tell assembler to change to section NAME with attributes FLAGS. If
421 DECL is non-NULL, it is the VAR_DECL or FUNCTION_DECL with which
422 this section is associated. */
424 void
425 named_section_real (const char *name, unsigned int flags, tree decl)
427 if (in_section != in_named || strcmp (name, in_named_name) != 0)
429 if (! set_named_section_flags (name, flags))
430 abort ();
432 targetm.asm_out.named_section (name, flags, decl);
434 if (flags & SECTION_FORGET)
435 in_section = no_section;
436 else
438 in_named_name = ggc_strdup (name);
439 in_section = in_named;
444 /* Tell assembler to change to section NAME for DECL.
445 If DECL is NULL, just switch to section NAME.
446 If NAME is NULL, get the name from DECL.
447 If RELOC is 1, the initializer for DECL contains relocs. */
449 void
450 named_section (tree decl, const char *name, int reloc)
452 unsigned int flags;
454 if (decl != NULL_TREE && !DECL_P (decl))
455 abort ();
456 if (name == NULL)
457 name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
459 if (strcmp (name, UNLIKELY_EXECUTED_TEXT_SECTION_NAME) == 0
460 && !unlikely_text_section_name)
462 unlikely_text_section_name = xmalloc
463 (strlen (UNLIKELY_EXECUTED_TEXT_SECTION_NAME) + 1
464 * sizeof (char));
465 strcpy (unlikely_text_section_name,
466 UNLIKELY_EXECUTED_TEXT_SECTION_NAME);
469 flags = targetm.section_type_flags (decl, name, reloc);
471 /* Sanity check user variables for flag changes. Non-user
472 section flag changes will abort in named_section_flags.
473 However, don't complain if SECTION_OVERRIDE is set.
474 We trust that the setter knows that it is safe to ignore
475 the default flags for this decl. */
476 if (decl && ! set_named_section_flags (name, flags))
478 flags = get_named_section_flags (name);
479 if ((flags & SECTION_OVERRIDE) == 0)
480 error ("%J%D causes a section type conflict", decl, decl);
483 named_section_real (name, flags, decl);
486 /* If required, set DECL_SECTION_NAME to a unique name. */
488 void
489 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
490 int flag_function_or_data_sections)
492 if (DECL_SECTION_NAME (decl) == NULL_TREE
493 && targetm.have_named_sections
494 && (flag_function_or_data_sections
495 || DECL_ONE_ONLY (decl)))
496 targetm.asm_out.unique_section (decl, reloc);
499 #ifdef BSS_SECTION_ASM_OP
501 /* Tell the assembler to switch to the bss section. */
503 void
504 bss_section (void)
506 if (in_section != in_bss)
508 fprintf (asm_out_file, "%s\n", BSS_SECTION_ASM_OP);
509 in_section = in_bss;
513 #ifdef ASM_OUTPUT_BSS
515 /* Utility function for ASM_OUTPUT_BSS for targets to use if
516 they don't support alignments in .bss.
517 ??? It is believed that this function will work in most cases so such
518 support is localized here. */
520 static void
521 asm_output_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
522 const char *name,
523 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
524 unsigned HOST_WIDE_INT rounded)
526 targetm.asm_out.globalize_label (file, name);
527 bss_section ();
528 #ifdef ASM_DECLARE_OBJECT_NAME
529 last_assemble_variable_decl = decl;
530 ASM_DECLARE_OBJECT_NAME (file, name, decl);
531 #else
532 /* Standard thing is just output label for the object. */
533 ASM_OUTPUT_LABEL (file, name);
534 #endif /* ASM_DECLARE_OBJECT_NAME */
535 ASM_OUTPUT_SKIP (file, rounded ? rounded : 1);
538 #endif
540 #ifdef ASM_OUTPUT_ALIGNED_BSS
542 /* Utility function for targets to use in implementing
543 ASM_OUTPUT_ALIGNED_BSS.
544 ??? It is believed that this function will work in most cases so such
545 support is localized here. */
547 static void
548 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
549 const char *name, unsigned HOST_WIDE_INT size,
550 int align)
552 bss_section ();
553 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
554 #ifdef ASM_DECLARE_OBJECT_NAME
555 last_assemble_variable_decl = decl;
556 ASM_DECLARE_OBJECT_NAME (file, name, decl);
557 #else
558 /* Standard thing is just output label for the object. */
559 ASM_OUTPUT_LABEL (file, name);
560 #endif /* ASM_DECLARE_OBJECT_NAME */
561 ASM_OUTPUT_SKIP (file, size ? size : 1);
564 #endif
566 #endif /* BSS_SECTION_ASM_OP */
568 /* Switch to the section for function DECL.
570 If DECL is NULL_TREE, switch to the text section.
571 ??? It's not clear that we will ever be passed NULL_TREE, but it's
572 safer to handle it. */
574 void
575 function_section (tree decl)
577 if (scan_ahead_for_unlikely_executed_note (get_insns()))
578 unlikely_text_section ();
579 else if (decl != NULL_TREE
580 && DECL_SECTION_NAME (decl) != NULL_TREE)
581 named_section (decl, (char *) 0, 0);
582 else
583 text_section ();
586 /* Switch to read-only data section associated with function DECL. */
588 void
589 default_function_rodata_section (tree decl)
591 if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
593 const char *name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
595 /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo. */
596 if (DECL_ONE_ONLY (decl) && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
598 size_t len = strlen (name) + 1;
599 char *rname = alloca (len);
601 memcpy (rname, name, len);
602 rname[14] = 'r';
603 named_section_real (rname, SECTION_LINKONCE, decl);
604 return;
606 /* For .text.foo we want to use .rodata.foo. */
607 else if (flag_function_sections && flag_data_sections
608 && strncmp (name, ".text.", 6) == 0)
610 size_t len = strlen (name) + 1;
611 char *rname = alloca (len + 2);
613 memcpy (rname, ".rodata", 7);
614 memcpy (rname + 7, name + 5, len - 5);
615 named_section_flags (rname, 0);
616 return;
620 readonly_data_section ();
623 /* Switch to read-only data section associated with function DECL
624 for targets where that section should be always the single
625 readonly data section. */
627 void
628 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
630 readonly_data_section ();
633 /* Switch to section for variable DECL. RELOC is the same as the
634 argument to SELECT_SECTION. */
636 void
637 variable_section (tree decl, int reloc)
639 if (IN_NAMED_SECTION (decl))
640 named_section (decl, NULL, reloc);
641 else
642 targetm.asm_out.select_section (decl, reloc, DECL_ALIGN (decl));
645 /* Tell assembler to switch to the section for string merging. */
647 void
648 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
649 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
650 unsigned int flags ATTRIBUTE_UNUSED)
652 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
653 && TREE_CODE (decl) == STRING_CST
654 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
655 && align <= 256
656 && TREE_STRING_LENGTH (decl) >= int_size_in_bytes (TREE_TYPE (decl)))
658 enum machine_mode mode;
659 unsigned int modesize;
660 const char *str;
661 int i, j, len, unit;
662 char name[30];
664 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
665 modesize = GET_MODE_BITSIZE (mode);
666 if (modesize >= 8 && modesize <= 256
667 && (modesize & (modesize - 1)) == 0)
669 if (align < modesize)
670 align = modesize;
672 str = TREE_STRING_POINTER (decl);
673 len = TREE_STRING_LENGTH (decl);
674 unit = GET_MODE_SIZE (mode);
676 /* Check for embedded NUL characters. */
677 for (i = 0; i < len; i += unit)
679 for (j = 0; j < unit; j++)
680 if (str[i + j] != '\0')
681 break;
682 if (j == unit)
683 break;
685 if (i == len - unit)
687 sprintf (name, ".rodata.str%d.%d", modesize / 8,
688 (int) (align / 8));
689 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
690 if (!i && modesize < align)
692 /* A "" string with requested alignment greater than
693 character size might cause a problem:
694 if some other string required even bigger
695 alignment than "", then linker might think the
696 "" is just part of padding after some other string
697 and not put it into the hash table initially.
698 But this means "" could have smaller alignment
699 than requested. */
700 #ifdef ASM_OUTPUT_SECTION_START
701 named_section_flags (name, flags);
702 ASM_OUTPUT_SECTION_START (asm_out_file);
703 #else
704 readonly_data_section ();
705 #endif
706 return;
709 named_section_flags (name, flags);
710 return;
715 readonly_data_section ();
718 /* Tell assembler to switch to the section for constant merging. */
720 void
721 mergeable_constant_section (enum machine_mode mode ATTRIBUTE_UNUSED,
722 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
723 unsigned int flags ATTRIBUTE_UNUSED)
725 unsigned int modesize = GET_MODE_BITSIZE (mode);
727 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
728 && mode != VOIDmode
729 && mode != BLKmode
730 && modesize <= align
731 && align >= 8
732 && align <= 256
733 && (align & (align - 1)) == 0)
735 char name[24];
737 sprintf (name, ".rodata.cst%d", (int) (align / 8));
738 flags |= (align / 8) | SECTION_MERGE;
739 named_section_flags (name, flags);
740 return;
743 readonly_data_section ();
746 /* Given NAME, a putative register name, discard any customary prefixes. */
748 static const char *
749 strip_reg_name (const char *name)
751 #ifdef REGISTER_PREFIX
752 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
753 name += strlen (REGISTER_PREFIX);
754 #endif
755 if (name[0] == '%' || name[0] == '#')
756 name++;
757 return name;
760 /* The user has asked for a DECL to have a particular name. Set (or
761 change) it in such a way that we don't prefix an underscore to
762 it. */
763 void
764 set_user_assembler_name (tree decl, const char *name)
766 char *starred = alloca (strlen (name) + 2);
767 starred[0] = '*';
768 strcpy (starred + 1, name);
769 change_decl_assembler_name (decl, get_identifier (starred));
770 SET_DECL_RTL (decl, NULL_RTX);
773 /* Decode an `asm' spec for a declaration as a register name.
774 Return the register number, or -1 if nothing specified,
775 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
776 or -3 if ASMSPEC is `cc' and is not recognized,
777 or -4 if ASMSPEC is `memory' and is not recognized.
778 Accept an exact spelling or a decimal number.
779 Prefixes such as % are optional. */
782 decode_reg_name (const char *asmspec)
784 if (asmspec != 0 && strlen (asmspec) != 0)
786 int i;
788 /* Get rid of confusing prefixes. */
789 asmspec = strip_reg_name (asmspec);
791 /* Allow a decimal number as a "register name". */
792 for (i = strlen (asmspec) - 1; i >= 0; i--)
793 if (! ISDIGIT (asmspec[i]))
794 break;
795 if (asmspec[0] != 0 && i < 0)
797 i = atoi (asmspec);
798 if (i < FIRST_PSEUDO_REGISTER && i >= 0)
799 return i;
800 else
801 return -2;
804 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
805 if (reg_names[i][0]
806 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
807 return i;
809 #ifdef ADDITIONAL_REGISTER_NAMES
811 static const struct { const char *const name; const int number; } table[]
812 = ADDITIONAL_REGISTER_NAMES;
814 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
815 if (! strcmp (asmspec, table[i].name))
816 return table[i].number;
818 #endif /* ADDITIONAL_REGISTER_NAMES */
820 if (!strcmp (asmspec, "memory"))
821 return -4;
823 if (!strcmp (asmspec, "cc"))
824 return -3;
826 return -2;
829 return -1;
832 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
833 have static storage duration. In other words, it should not be an
834 automatic variable, including PARM_DECLs.
836 There is, however, one exception: this function handles variables
837 explicitly placed in a particular register by the user.
839 This is never called for PARM_DECL nodes. */
841 void
842 make_decl_rtl (tree decl)
844 const char *name = 0;
845 int reg_number;
846 rtx x;
848 /* Check that we are not being given an automatic variable. */
849 /* A weak alias has TREE_PUBLIC set but not the other bits. */
850 if (TREE_CODE (decl) == PARM_DECL
851 || TREE_CODE (decl) == RESULT_DECL
852 || (TREE_CODE (decl) == VAR_DECL
853 && !TREE_STATIC (decl)
854 && !TREE_PUBLIC (decl)
855 && !DECL_EXTERNAL (decl)
856 && !DECL_REGISTER (decl)))
857 abort ();
858 /* And that we were not given a type or a label. */
859 else if (TREE_CODE (decl) == TYPE_DECL
860 || TREE_CODE (decl) == LABEL_DECL)
861 abort ();
863 /* For a duplicate declaration, we can be called twice on the
864 same DECL node. Don't discard the RTL already made. */
865 if (DECL_RTL_SET_P (decl))
867 /* If the old RTL had the wrong mode, fix the mode. */
868 if (GET_MODE (DECL_RTL (decl)) != DECL_MODE (decl))
869 SET_DECL_RTL (decl, adjust_address_nv (DECL_RTL (decl),
870 DECL_MODE (decl), 0));
872 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
873 return;
875 /* ??? Another way to do this would be to maintain a hashed
876 table of such critters. Instead of adding stuff to a DECL
877 to give certain attributes to it, we could use an external
878 hash map from DECL to set of attributes. */
880 /* Let the target reassign the RTL if it wants.
881 This is necessary, for example, when one machine specific
882 decl attribute overrides another. */
883 targetm.encode_section_info (decl, DECL_RTL (decl), false);
885 /* Make this function static known to the mudflap runtime. */
886 if (flag_mudflap && TREE_CODE (decl) == VAR_DECL)
887 mudflap_enqueue_decl (decl);
889 return;
892 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
894 reg_number = decode_reg_name (name);
896 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
898 /* First detect errors in declaring global registers. */
899 if (reg_number == -1)
900 error ("%Jregister name not specified for %qD", decl, decl);
901 else if (reg_number < 0)
902 error ("%Jinvalid register name for %qD", decl, decl);
903 else if (TYPE_MODE (TREE_TYPE (decl)) == BLKmode)
904 error ("%Jdata type of %qD isn%'t suitable for a register",
905 decl, decl);
906 else if (! HARD_REGNO_MODE_OK (reg_number, TYPE_MODE (TREE_TYPE (decl))))
907 error ("%Jregister specified for %qD isn%'t suitable for data type",
908 decl, decl);
909 /* Now handle properly declared static register variables. */
910 else
912 int nregs;
914 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
916 DECL_INITIAL (decl) = 0;
917 error ("global register variable has initial value");
919 if (TREE_THIS_VOLATILE (decl))
920 warning ("volatile register variables don%'t "
921 "work as you might wish");
923 /* If the user specified one of the eliminables registers here,
924 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
925 confused with that register and be eliminated. This usage is
926 somewhat suspect... */
928 SET_DECL_RTL (decl, gen_rtx_raw_REG (DECL_MODE (decl), reg_number));
929 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
930 REG_USERVAR_P (DECL_RTL (decl)) = 1;
932 if (TREE_STATIC (decl))
934 /* Make this register global, so not usable for anything
935 else. */
936 #ifdef ASM_DECLARE_REGISTER_GLOBAL
937 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
938 #endif
939 nregs = hard_regno_nregs[reg_number][DECL_MODE (decl)];
940 while (nregs > 0)
941 globalize_reg (reg_number + --nregs);
944 /* As a register variable, it has no section. */
945 return;
949 /* Now handle ordinary static variables and functions (in memory).
950 Also handle vars declared register invalidly. */
952 if (name[0] == '*' && (reg_number >= 0 || reg_number == -3))
953 error ("%Jregister name given for non-register variable %qD", decl, decl);
955 /* Specifying a section attribute on a variable forces it into a
956 non-.bss section, and thus it cannot be common. */
957 if (TREE_CODE (decl) == VAR_DECL
958 && DECL_SECTION_NAME (decl) != NULL_TREE
959 && DECL_INITIAL (decl) == NULL_TREE
960 && DECL_COMMON (decl))
961 DECL_COMMON (decl) = 0;
963 /* Variables can't be both common and weak. */
964 if (TREE_CODE (decl) == VAR_DECL && DECL_WEAK (decl))
965 DECL_COMMON (decl) = 0;
967 x = gen_rtx_SYMBOL_REF (Pmode, name);
968 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
969 SYMBOL_REF_DECL (x) = decl;
971 x = gen_rtx_MEM (DECL_MODE (decl), x);
972 if (TREE_CODE (decl) != FUNCTION_DECL)
973 set_mem_attributes (x, decl, 1);
974 SET_DECL_RTL (decl, x);
976 /* Optionally set flags or add text to the name to record information
977 such as that it is a function name.
978 If the name is changed, the macro ASM_OUTPUT_LABELREF
979 will have to know how to strip this information. */
980 targetm.encode_section_info (decl, DECL_RTL (decl), true);
982 /* Make this function static known to the mudflap runtime. */
983 if (flag_mudflap && TREE_CODE (decl) == VAR_DECL)
984 mudflap_enqueue_decl (decl);
987 /* Make the rtl for variable VAR be volatile.
988 Use this only for static variables. */
990 void
991 make_var_volatile (tree var)
993 if (!MEM_P (DECL_RTL (var)))
994 abort ();
996 MEM_VOLATILE_P (DECL_RTL (var)) = 1;
999 /* Output a string of literal assembler code
1000 for an `asm' keyword used between functions. */
1002 void
1003 assemble_asm (tree string)
1005 app_enable ();
1007 if (TREE_CODE (string) == ADDR_EXPR)
1008 string = TREE_OPERAND (string, 0);
1010 fprintf (asm_out_file, "\t%s\n", TREE_STRING_POINTER (string));
1013 /* Record an element in the table of global destructors. SYMBOL is
1014 a SYMBOL_REF of the function to be called; PRIORITY is a number
1015 between 0 and MAX_INIT_PRIORITY. */
1017 void
1018 default_stabs_asm_out_destructor (rtx symbol, int priority ATTRIBUTE_UNUSED)
1020 /* Tell GNU LD that this is part of the static destructor set.
1021 This will work for any system that uses stabs, most usefully
1022 aout systems. */
1023 fprintf (asm_out_file, "%s\"___DTOR_LIST__\",22,0,0,", ASM_STABS_OP);
1024 assemble_name (asm_out_file, XSTR (symbol, 0));
1025 fputc ('\n', asm_out_file);
1028 void
1029 default_named_section_asm_out_destructor (rtx symbol, int priority)
1031 const char *section = ".dtors";
1032 char buf[16];
1034 /* ??? This only works reliably with the GNU linker. */
1035 if (priority != DEFAULT_INIT_PRIORITY)
1037 sprintf (buf, ".dtors.%.5u",
1038 /* Invert the numbering so the linker puts us in the proper
1039 order; constructors are run from right to left, and the
1040 linker sorts in increasing order. */
1041 MAX_INIT_PRIORITY - priority);
1042 section = buf;
1045 named_section_flags (section, SECTION_WRITE);
1046 assemble_align (POINTER_SIZE);
1047 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1050 #ifdef DTORS_SECTION_ASM_OP
1051 void
1052 dtors_section (void)
1054 if (in_section != in_dtors)
1056 in_section = in_dtors;
1057 fputs (DTORS_SECTION_ASM_OP, asm_out_file);
1058 fputc ('\n', asm_out_file);
1062 void
1063 default_dtor_section_asm_out_destructor (rtx symbol,
1064 int priority ATTRIBUTE_UNUSED)
1066 dtors_section ();
1067 assemble_align (POINTER_SIZE);
1068 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1070 #endif
1072 /* Likewise for global constructors. */
1074 void
1075 default_stabs_asm_out_constructor (rtx symbol, int priority ATTRIBUTE_UNUSED)
1077 /* Tell GNU LD that this is part of the static destructor set.
1078 This will work for any system that uses stabs, most usefully
1079 aout systems. */
1080 fprintf (asm_out_file, "%s\"___CTOR_LIST__\",22,0,0,", ASM_STABS_OP);
1081 assemble_name (asm_out_file, XSTR (symbol, 0));
1082 fputc ('\n', asm_out_file);
1085 void
1086 default_named_section_asm_out_constructor (rtx symbol, int priority)
1088 const char *section = ".ctors";
1089 char buf[16];
1091 /* ??? This only works reliably with the GNU linker. */
1092 if (priority != DEFAULT_INIT_PRIORITY)
1094 sprintf (buf, ".ctors.%.5u",
1095 /* Invert the numbering so the linker puts us in the proper
1096 order; constructors are run from right to left, and the
1097 linker sorts in increasing order. */
1098 MAX_INIT_PRIORITY - priority);
1099 section = buf;
1102 named_section_flags (section, SECTION_WRITE);
1103 assemble_align (POINTER_SIZE);
1104 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1107 #ifdef CTORS_SECTION_ASM_OP
1108 void
1109 ctors_section (void)
1111 if (in_section != in_ctors)
1113 in_section = in_ctors;
1114 fputs (CTORS_SECTION_ASM_OP, asm_out_file);
1115 fputc ('\n', asm_out_file);
1119 void
1120 default_ctor_section_asm_out_constructor (rtx symbol,
1121 int priority ATTRIBUTE_UNUSED)
1123 ctors_section ();
1124 assemble_align (POINTER_SIZE);
1125 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1127 #endif
1129 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1130 a nonzero value if the constant pool should be output before the
1131 start of the function, or a zero value if the pool should output
1132 after the end of the function. The default is to put it before the
1133 start. */
1135 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1136 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1137 #endif
1139 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1140 to be output to assembler.
1141 Set first_global_object_name and weak_global_object_name as appropriate. */
1143 void
1144 notice_global_symbol (tree decl)
1146 const char **type = &first_global_object_name;
1148 if (first_global_object_name
1149 || !TREE_PUBLIC (decl) || DECL_EXTERNAL (decl)
1150 || !DECL_NAME (decl)
1151 || (TREE_CODE (decl) != FUNCTION_DECL
1152 && (TREE_CODE (decl) != VAR_DECL
1153 || (DECL_COMMON (decl)
1154 && (DECL_INITIAL (decl) == 0
1155 || DECL_INITIAL (decl) == error_mark_node))))
1156 || !MEM_P (DECL_RTL (decl)))
1157 return;
1159 /* We win when global object is found, but it is useful to know about weak
1160 symbol as well so we can produce nicer unique names. */
1161 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl))
1162 type = &weak_global_object_name;
1164 if (!*type)
1166 const char *p;
1167 char *name;
1168 rtx decl_rtl = DECL_RTL (decl);
1170 p = targetm.strip_name_encoding (XSTR (XEXP (decl_rtl, 0), 0));
1171 name = xstrdup (p);
1173 *type = name;
1177 /* Output assembler code for the constant pool of a function and associated
1178 with defining the name of the function. DECL describes the function.
1179 NAME is the function's name. For the constant pool, we use the current
1180 constant pool data. */
1182 void
1183 assemble_start_function (tree decl, const char *fnname)
1185 int align;
1187 if (unlikely_text_section_name)
1188 free (unlikely_text_section_name);
1190 unlikely_section_label_printed = false;
1191 unlikely_text_section_name = NULL;
1193 unlikely_section_label = reconcat (unlikely_section_label,
1194 fnname, ".unlikely_section", NULL);
1196 /* The following code does not need preprocessing in the assembler. */
1198 app_disable ();
1200 if (CONSTANT_POOL_BEFORE_FUNCTION)
1201 output_constant_pool (fnname, decl);
1203 /* Make sure the cold text (code) section is properly aligned. This
1204 is necessary here in the case where the function has both hot and
1205 cold sections, because we don't want to re-set the alignment when the
1206 section switch happens mid-function. We don't need to set the hot
1207 section alignment here, because code further down in this function
1208 sets the alignment for whichever section comes first, and if there
1209 is a hot section it is guaranteed to be first. */
1211 if (flag_reorder_blocks_and_partition)
1213 unlikely_text_section ();
1214 assemble_align (FUNCTION_BOUNDARY);
1217 resolve_unique_section (decl, 0, flag_function_sections);
1218 function_section (decl);
1220 /* Tell assembler to move to target machine's alignment for functions. */
1221 align = floor_log2 (FUNCTION_BOUNDARY / BITS_PER_UNIT);
1222 if (align < force_align_functions_log)
1223 align = force_align_functions_log;
1224 if (align > 0)
1226 ASM_OUTPUT_ALIGN (asm_out_file, align);
1229 /* Handle a user-specified function alignment.
1230 Note that we still need to align to FUNCTION_BOUNDARY, as above,
1231 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1232 if (align_functions_log > align
1233 && cfun->function_frequency != FUNCTION_FREQUENCY_UNLIKELY_EXECUTED)
1235 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1236 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1237 align_functions_log, align_functions - 1);
1238 #else
1239 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1240 #endif
1243 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1244 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1245 #endif
1247 (*debug_hooks->begin_function) (decl);
1249 /* Make function name accessible from other files, if appropriate. */
1251 if (TREE_PUBLIC (decl))
1253 notice_global_symbol (decl);
1255 globalize_decl (decl);
1257 maybe_assemble_visibility (decl);
1260 if (DECL_PRESERVE_P (decl))
1261 targetm.asm_out.mark_decl_preserved (fnname);
1263 /* Do any machine/system dependent processing of the function name. */
1264 #ifdef ASM_DECLARE_FUNCTION_NAME
1265 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1266 #else
1267 /* Standard thing is just output label for the function. */
1268 ASM_OUTPUT_LABEL (asm_out_file, fnname);
1269 #endif /* ASM_DECLARE_FUNCTION_NAME */
1271 if (in_unlikely_text_section ()
1272 && !unlikely_section_label_printed)
1274 ASM_OUTPUT_LABEL (asm_out_file, unlikely_section_label);
1275 unlikely_section_label_printed = true;
1279 /* Output assembler code associated with defining the size of the
1280 function. DECL describes the function. NAME is the function's name. */
1282 void
1283 assemble_end_function (tree decl, const char *fnname)
1285 #ifdef ASM_DECLARE_FUNCTION_SIZE
1286 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1287 #endif
1288 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1290 output_constant_pool (fnname, decl);
1291 function_section (decl); /* need to switch back */
1295 /* Assemble code to leave SIZE bytes of zeros. */
1297 void
1298 assemble_zeros (unsigned HOST_WIDE_INT size)
1300 /* Do no output if -fsyntax-only. */
1301 if (flag_syntax_only)
1302 return;
1304 #ifdef ASM_NO_SKIP_IN_TEXT
1305 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1306 so we must output 0s explicitly in the text section. */
1307 if ((ASM_NO_SKIP_IN_TEXT && in_text_section ())
1308 || (ASM_NO_SKIP_IN_TEXT && in_unlikely_text_section ()))
1310 unsigned HOST_WIDE_INT i;
1311 for (i = 0; i < size; i++)
1312 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1314 else
1315 #endif
1316 if (size > 0)
1317 ASM_OUTPUT_SKIP (asm_out_file, size);
1320 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1322 void
1323 assemble_align (int align)
1325 if (align > BITS_PER_UNIT)
1327 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1331 /* Assemble a string constant with the specified C string as contents. */
1333 void
1334 assemble_string (const char *p, int size)
1336 int pos = 0;
1337 int maximum = 2000;
1339 /* If the string is very long, split it up. */
1341 while (pos < size)
1343 int thissize = size - pos;
1344 if (thissize > maximum)
1345 thissize = maximum;
1347 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1349 pos += thissize;
1350 p += thissize;
1355 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1356 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1357 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1358 #else
1359 #if defined ASM_OUTPUT_ALIGNED_LOCAL
1360 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1361 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, DECL_ALIGN (decl))
1362 #else
1363 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1364 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded)
1365 #endif
1366 #endif
1368 #if defined ASM_OUTPUT_ALIGNED_BSS
1369 #define ASM_EMIT_BSS(decl, name, size, rounded) \
1370 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1371 #else
1372 #if defined ASM_OUTPUT_BSS
1373 #define ASM_EMIT_BSS(decl, name, size, rounded) \
1374 ASM_OUTPUT_BSS (asm_out_file, decl, name, size, rounded)
1375 #else
1376 #undef ASM_EMIT_BSS
1377 #endif
1378 #endif
1380 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1381 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1382 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1383 #else
1384 #if defined ASM_OUTPUT_ALIGNED_COMMON
1385 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1386 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size, DECL_ALIGN (decl))
1387 #else
1388 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1389 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded)
1390 #endif
1391 #endif
1393 static bool
1394 asm_emit_uninitialised (tree decl, const char *name,
1395 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1396 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1398 enum
1400 asm_dest_common,
1401 asm_dest_bss,
1402 asm_dest_local
1404 destination = asm_dest_local;
1406 /* ??? We should handle .bss via select_section mechanisms rather than
1407 via special target hooks. That would eliminate this special case. */
1408 if (TREE_PUBLIC (decl))
1410 if (!DECL_COMMON (decl))
1411 #ifdef ASM_EMIT_BSS
1412 destination = asm_dest_bss;
1413 #else
1414 return false;
1415 #endif
1416 else
1417 destination = asm_dest_common;
1420 if (destination == asm_dest_bss)
1421 globalize_decl (decl);
1422 resolve_unique_section (decl, 0, flag_data_sections);
1424 if (flag_shared_data)
1426 switch (destination)
1428 #ifdef ASM_OUTPUT_SHARED_BSS
1429 case asm_dest_bss:
1430 ASM_OUTPUT_SHARED_BSS (asm_out_file, decl, name, size, rounded);
1431 return;
1432 #endif
1433 #ifdef ASM_OUTPUT_SHARED_COMMON
1434 case asm_dest_common:
1435 ASM_OUTPUT_SHARED_COMMON (asm_out_file, name, size, rounded);
1436 return;
1437 #endif
1438 #ifdef ASM_OUTPUT_SHARED_LOCAL
1439 case asm_dest_local:
1440 ASM_OUTPUT_SHARED_LOCAL (asm_out_file, name, size, rounded);
1441 return;
1442 #endif
1443 default:
1444 break;
1448 switch (destination)
1450 #ifdef ASM_EMIT_BSS
1451 case asm_dest_bss:
1452 ASM_EMIT_BSS (decl, name, size, rounded);
1453 break;
1454 #endif
1455 case asm_dest_common:
1456 ASM_EMIT_COMMON (decl, name, size, rounded);
1457 break;
1458 case asm_dest_local:
1459 ASM_EMIT_LOCAL (decl, name, size, rounded);
1460 break;
1461 default:
1462 abort ();
1465 return true;
1468 /* Assemble everything that is needed for a variable or function declaration.
1469 Not used for automatic variables, and not used for function definitions.
1470 Should not be called for variables of incomplete structure type.
1472 TOP_LEVEL is nonzero if this variable has file scope.
1473 AT_END is nonzero if this is the special handling, at end of compilation,
1474 to define things that have had only tentative definitions.
1475 DONT_OUTPUT_DATA if nonzero means don't actually output the
1476 initial value (that will be done by the caller). */
1478 void
1479 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
1480 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
1482 const char *name;
1483 unsigned int align;
1484 int reloc = 0;
1485 rtx decl_rtl;
1487 if (lang_hooks.decls.prepare_assemble_variable)
1488 lang_hooks.decls.prepare_assemble_variable (decl);
1490 last_assemble_variable_decl = 0;
1492 /* Normally no need to say anything here for external references,
1493 since assemble_external is called by the language-specific code
1494 when a declaration is first seen. */
1496 if (DECL_EXTERNAL (decl))
1497 return;
1499 /* Output no assembler code for a function declaration.
1500 Only definitions of functions output anything. */
1502 if (TREE_CODE (decl) == FUNCTION_DECL)
1503 return;
1505 /* Do nothing for global register variables. */
1506 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
1508 TREE_ASM_WRITTEN (decl) = 1;
1509 return;
1512 /* If type was incomplete when the variable was declared,
1513 see if it is complete now. */
1515 if (DECL_SIZE (decl) == 0)
1516 layout_decl (decl, 0);
1518 /* Still incomplete => don't allocate it; treat the tentative defn
1519 (which is what it must have been) as an `extern' reference. */
1521 if (!dont_output_data && DECL_SIZE (decl) == 0)
1523 error ("%Jstorage size of %qD isn%'t known", decl, decl);
1524 TREE_ASM_WRITTEN (decl) = 1;
1525 return;
1528 /* The first declaration of a variable that comes through this function
1529 decides whether it is global (in C, has external linkage)
1530 or local (in C, has internal linkage). So do nothing more
1531 if this function has already run. */
1533 if (TREE_ASM_WRITTEN (decl))
1534 return;
1536 /* Make sure targetm.encode_section_info is invoked before we set
1537 ASM_WRITTEN. */
1538 decl_rtl = DECL_RTL (decl);
1540 TREE_ASM_WRITTEN (decl) = 1;
1542 /* Do no output if -fsyntax-only. */
1543 if (flag_syntax_only)
1544 return;
1546 app_disable ();
1548 if (! dont_output_data
1549 && ! host_integerp (DECL_SIZE_UNIT (decl), 1))
1551 error ("%Jsize of variable %qD is too large", decl, decl);
1552 return;
1555 name = XSTR (XEXP (decl_rtl, 0), 0);
1556 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
1557 notice_global_symbol (decl);
1559 /* Compute the alignment of this data. */
1561 align = DECL_ALIGN (decl);
1563 /* In the case for initialing an array whose length isn't specified,
1564 where we have not yet been able to do the layout,
1565 figure out the proper alignment now. */
1566 if (dont_output_data && DECL_SIZE (decl) == 0
1567 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
1568 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
1570 /* Some object file formats have a maximum alignment which they support.
1571 In particular, a.out format supports a maximum alignment of 4. */
1572 if (align > MAX_OFILE_ALIGNMENT)
1574 warning ("%Jalignment of %qD is greater than maximum object "
1575 "file alignment. Using %d", decl, decl,
1576 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
1577 align = MAX_OFILE_ALIGNMENT;
1580 /* On some machines, it is good to increase alignment sometimes. */
1581 if (! DECL_USER_ALIGN (decl))
1583 #ifdef DATA_ALIGNMENT
1584 align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1585 #endif
1586 #ifdef CONSTANT_ALIGNMENT
1587 if (DECL_INITIAL (decl) != 0 && DECL_INITIAL (decl) != error_mark_node)
1588 align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
1589 #endif
1592 /* Reset the alignment in case we have made it tighter, so we can benefit
1593 from it in get_pointer_alignment. */
1594 DECL_ALIGN (decl) = align;
1595 set_mem_align (decl_rtl, align);
1597 if (TREE_PUBLIC (decl))
1598 maybe_assemble_visibility (decl);
1600 if (DECL_PRESERVE_P (decl))
1601 targetm.asm_out.mark_decl_preserved (name);
1603 /* Output any data that we will need to use the address of. */
1604 if (DECL_INITIAL (decl) == error_mark_node)
1605 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1606 else if (DECL_INITIAL (decl))
1608 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1609 output_addressed_constants (DECL_INITIAL (decl));
1611 resolve_unique_section (decl, reloc, flag_data_sections);
1613 /* Handle uninitialized definitions. */
1615 /* If the decl has been given an explicit section name, then it
1616 isn't common, and shouldn't be handled as such. */
1617 if (DECL_SECTION_NAME (decl) || dont_output_data)
1619 /* We don't implement common thread-local data at present. */
1620 else if (DECL_THREAD_LOCAL (decl))
1622 if (DECL_COMMON (decl))
1623 sorry ("thread-local COMMON data not implemented");
1625 else if (DECL_INITIAL (decl) == 0
1626 || DECL_INITIAL (decl) == error_mark_node
1627 || (flag_zero_initialized_in_bss
1628 /* Leave constant zeroes in .rodata so they can be shared. */
1629 && !TREE_READONLY (decl)
1630 && initializer_zerop (DECL_INITIAL (decl))))
1632 unsigned HOST_WIDE_INT size = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
1633 unsigned HOST_WIDE_INT rounded = size;
1635 /* Don't allocate zero bytes of common,
1636 since that means "undefined external" in the linker. */
1637 if (size == 0)
1638 rounded = 1;
1640 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1641 so that each uninitialized object starts on such a boundary. */
1642 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
1643 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1644 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1646 #if !defined(ASM_OUTPUT_ALIGNED_COMMON) && !defined(ASM_OUTPUT_ALIGNED_DECL_COMMON) && !defined(ASM_OUTPUT_ALIGNED_BSS)
1647 if ((unsigned HOST_WIDE_INT) DECL_ALIGN_UNIT (decl) > rounded)
1648 warning ("%Jrequested alignment for %qD is greater than "
1649 "implemented alignment of %d", decl, decl, rounded);
1650 #endif
1652 /* If the target cannot output uninitialized but not common global data
1653 in .bss, then we have to use .data, so fall through. */
1654 if (asm_emit_uninitialised (decl, name, size, rounded))
1655 return;
1658 /* Handle initialized definitions.
1659 Also handle uninitialized global definitions if -fno-common and the
1660 target doesn't support ASM_OUTPUT_BSS. */
1662 /* First make the assembler name(s) global if appropriate. */
1663 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
1664 globalize_decl (decl);
1666 /* Switch to the appropriate section. */
1667 variable_section (decl, reloc);
1669 /* dbxout.c needs to know this. */
1670 if (in_text_section () || in_unlikely_text_section ())
1671 DECL_IN_TEXT_SECTION (decl) = 1;
1673 /* Output the alignment of this data. */
1674 if (align > BITS_PER_UNIT)
1675 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (DECL_ALIGN_UNIT (decl)));
1677 /* Do any machine/system dependent processing of the object. */
1678 #ifdef ASM_DECLARE_OBJECT_NAME
1679 last_assemble_variable_decl = decl;
1680 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
1681 #else
1682 /* Standard thing is just output label for the object. */
1683 ASM_OUTPUT_LABEL (asm_out_file, name);
1684 #endif /* ASM_DECLARE_OBJECT_NAME */
1686 if (!dont_output_data)
1688 if (DECL_INITIAL (decl)
1689 && DECL_INITIAL (decl) != error_mark_node
1690 && !initializer_zerop (DECL_INITIAL (decl)))
1691 /* Output the actual data. */
1692 output_constant (DECL_INITIAL (decl),
1693 tree_low_cst (DECL_SIZE_UNIT (decl), 1),
1694 align);
1695 else
1696 /* Leave space for it. */
1697 assemble_zeros (tree_low_cst (DECL_SIZE_UNIT (decl), 1));
1701 /* Return 1 if type TYPE contains any pointers. */
1703 static int
1704 contains_pointers_p (tree type)
1706 switch (TREE_CODE (type))
1708 case POINTER_TYPE:
1709 case REFERENCE_TYPE:
1710 /* I'm not sure whether OFFSET_TYPE needs this treatment,
1711 so I'll play safe and return 1. */
1712 case OFFSET_TYPE:
1713 return 1;
1715 case RECORD_TYPE:
1716 case UNION_TYPE:
1717 case QUAL_UNION_TYPE:
1719 tree fields;
1720 /* For a type that has fields, see if the fields have pointers. */
1721 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
1722 if (TREE_CODE (fields) == FIELD_DECL
1723 && contains_pointers_p (TREE_TYPE (fields)))
1724 return 1;
1725 return 0;
1728 case ARRAY_TYPE:
1729 /* An array type contains pointers if its element type does. */
1730 return contains_pointers_p (TREE_TYPE (type));
1732 default:
1733 return 0;
1737 #ifdef ASM_OUTPUT_EXTERNAL
1738 /* True if DECL is a function decl for which no out-of-line copy exists.
1739 It is assumed that DECL's assembler name has been set. */
1741 static bool
1742 incorporeal_function_p (tree decl)
1744 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
1746 const char *name;
1748 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
1749 && DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA)
1750 return true;
1752 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
1753 if (strncmp (name, "__builtin_", strlen ("__builtin_")) == 0)
1754 return true;
1756 return false;
1758 #endif
1760 /* Output something to declare an external symbol to the assembler.
1761 (Most assemblers don't need this, so we normally output nothing.)
1762 Do nothing if DECL is not external. */
1764 void
1765 assemble_external (tree decl ATTRIBUTE_UNUSED)
1767 /* Because most platforms do not define ASM_OUTPUT_EXTERNAL, the
1768 main body of this code is only rarely exercised. To provide some
1769 testing, on all platforms, we make sure that the ASM_OUT_FILE is
1770 open. If it's not, we should not be calling this function. */
1771 if (!asm_out_file)
1772 abort ();
1774 #ifdef ASM_OUTPUT_EXTERNAL
1775 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
1777 rtx rtl = DECL_RTL (decl);
1779 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
1780 && !SYMBOL_REF_USED (XEXP (rtl, 0))
1781 && !incorporeal_function_p (decl))
1783 /* Some systems do require some output. */
1784 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
1785 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
1788 #endif
1791 /* Similar, for calling a library function FUN. */
1793 void
1794 assemble_external_libcall (rtx fun)
1796 /* Declare library function name external when first used, if nec. */
1797 if (! SYMBOL_REF_USED (fun))
1799 SYMBOL_REF_USED (fun) = 1;
1800 targetm.asm_out.external_libcall (fun);
1804 /* Assemble a label named NAME. */
1806 void
1807 assemble_label (const char *name)
1809 ASM_OUTPUT_LABEL (asm_out_file, name);
1812 /* Set the symbol_referenced flag for ID. */
1813 void
1814 mark_referenced (tree id)
1816 TREE_SYMBOL_REFERENCED (id) = 1;
1819 /* Set the symbol_referenced flag for DECL and notify callgraph. */
1820 void
1821 mark_decl_referenced (tree decl)
1823 if (TREE_CODE (decl) == FUNCTION_DECL)
1824 cgraph_mark_needed_node (cgraph_node (decl));
1825 else if (TREE_CODE (decl) == VAR_DECL)
1826 cgraph_varpool_mark_needed_node (cgraph_varpool_node (decl));
1827 /* else do nothing - we can get various sorts of CST nodes here,
1828 which do not need to be marked. */
1831 /* Output to FILE a reference to the assembler name of a C-level name NAME.
1832 If NAME starts with a *, the rest of NAME is output verbatim.
1833 Otherwise NAME is transformed in an implementation-defined way
1834 (usually by the addition of an underscore).
1835 Many macros in the tm file are defined to call this function. */
1837 void
1838 assemble_name (FILE *file, const char *name)
1840 const char *real_name;
1841 tree id;
1843 real_name = targetm.strip_name_encoding (name);
1845 id = maybe_get_identifier (real_name);
1846 if (id)
1847 mark_referenced (id);
1849 if (name[0] == '*')
1850 fputs (&name[1], file);
1851 else
1852 ASM_OUTPUT_LABELREF (file, name);
1855 /* Allocate SIZE bytes writable static space with a gensym name
1856 and return an RTX to refer to its address. */
1859 assemble_static_space (unsigned HOST_WIDE_INT size)
1861 char name[12];
1862 const char *namestring;
1863 rtx x;
1865 #if 0
1866 if (flag_shared_data)
1867 data_section ();
1868 #endif
1870 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
1871 ++const_labelno;
1872 namestring = ggc_strdup (name);
1874 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
1875 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
1877 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
1878 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
1879 BIGGEST_ALIGNMENT);
1880 #else
1881 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
1882 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
1883 #else
1885 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1886 so that each uninitialized object starts on such a boundary. */
1887 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
1888 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
1889 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
1890 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1891 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1892 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1894 #endif
1895 #endif
1896 return x;
1899 /* Assemble the static constant template for function entry trampolines.
1900 This is done at most once per compilation.
1901 Returns an RTX for the address of the template. */
1903 static GTY(()) rtx initial_trampoline;
1905 #ifdef TRAMPOLINE_TEMPLATE
1907 assemble_trampoline_template (void)
1909 char label[256];
1910 const char *name;
1911 int align;
1912 rtx symbol;
1914 if (initial_trampoline)
1915 return initial_trampoline;
1917 /* By default, put trampoline templates in read-only data section. */
1919 #ifdef TRAMPOLINE_SECTION
1920 TRAMPOLINE_SECTION ();
1921 #else
1922 readonly_data_section ();
1923 #endif
1925 /* Write the assembler code to define one. */
1926 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
1927 if (align > 0)
1929 ASM_OUTPUT_ALIGN (asm_out_file, align);
1932 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
1933 TRAMPOLINE_TEMPLATE (asm_out_file);
1935 /* Record the rtl to refer to it. */
1936 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
1937 name = ggc_strdup (label);
1938 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
1939 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
1941 initial_trampoline = gen_rtx_MEM (BLKmode, symbol);
1942 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
1944 return initial_trampoline;
1946 #endif
1948 /* A and B are either alignments or offsets. Return the minimum alignment
1949 that may be assumed after adding the two together. */
1951 static inline unsigned
1952 min_align (unsigned int a, unsigned int b)
1954 return (a | b) & -(a | b);
1957 /* Return the assembler directive for creating a given kind of integer
1958 object. SIZE is the number of bytes in the object and ALIGNED_P
1959 indicates whether it is known to be aligned. Return NULL if the
1960 assembly dialect has no such directive.
1962 The returned string should be printed at the start of a new line and
1963 be followed immediately by the object's initial value. */
1965 const char *
1966 integer_asm_op (int size, int aligned_p)
1968 struct asm_int_op *ops;
1970 if (aligned_p)
1971 ops = &targetm.asm_out.aligned_op;
1972 else
1973 ops = &targetm.asm_out.unaligned_op;
1975 switch (size)
1977 case 1:
1978 return targetm.asm_out.byte_op;
1979 case 2:
1980 return ops->hi;
1981 case 4:
1982 return ops->si;
1983 case 8:
1984 return ops->di;
1985 case 16:
1986 return ops->ti;
1987 default:
1988 return NULL;
1992 /* Use directive OP to assemble an integer object X. Print OP at the
1993 start of the line, followed immediately by the value of X. */
1995 void
1996 assemble_integer_with_op (const char *op, rtx x)
1998 fputs (op, asm_out_file);
1999 output_addr_const (asm_out_file, x);
2000 fputc ('\n', asm_out_file);
2003 /* The default implementation of the asm_out.integer target hook. */
2005 bool
2006 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2007 unsigned int size ATTRIBUTE_UNUSED,
2008 int aligned_p ATTRIBUTE_UNUSED)
2010 const char *op = integer_asm_op (size, aligned_p);
2011 /* Avoid GAS bugs for values > word size. */
2012 if (size > UNITS_PER_WORD)
2013 return false;
2014 return op && (assemble_integer_with_op (op, x), true);
2017 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2018 the alignment of the integer in bits. Return 1 if we were able to output
2019 the constant, otherwise 0. If FORCE is nonzero, abort if we can't output
2020 the constant. */
2022 bool
2023 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2025 int aligned_p;
2027 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2029 /* See if the target hook can handle this kind of object. */
2030 if (targetm.asm_out.integer (x, size, aligned_p))
2031 return true;
2033 /* If the object is a multi-byte one, try splitting it up. Split
2034 it into words it if is multi-word, otherwise split it into bytes. */
2035 if (size > 1)
2037 enum machine_mode omode, imode;
2038 unsigned int subalign;
2039 unsigned int subsize, i;
2041 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2042 subalign = MIN (align, subsize * BITS_PER_UNIT);
2043 omode = mode_for_size (subsize * BITS_PER_UNIT, MODE_INT, 0);
2044 imode = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
2046 for (i = 0; i < size; i += subsize)
2048 rtx partial = simplify_subreg (omode, x, imode, i);
2049 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2050 break;
2052 if (i == size)
2053 return true;
2055 /* If we've printed some of it, but not all of it, there's no going
2056 back now. */
2057 if (i > 0)
2058 abort ();
2061 if (force)
2062 abort ();
2064 return false;
2067 void
2068 assemble_real (REAL_VALUE_TYPE d, enum machine_mode mode, unsigned int align)
2070 long data[4];
2071 int i;
2072 int bitsize, nelts, nunits, units_per;
2074 /* This is hairy. We have a quantity of known size. real_to_target
2075 will put it into an array of *host* longs, 32 bits per element
2076 (even if long is more than 32 bits). We need to determine the
2077 number of array elements that are occupied (nelts) and the number
2078 of *target* min-addressable units that will be occupied in the
2079 object file (nunits). We cannot assume that 32 divides the
2080 mode's bitsize (size * BITS_PER_UNIT) evenly.
2082 size * BITS_PER_UNIT is used here to make sure that padding bits
2083 (which might appear at either end of the value; real_to_target
2084 will include the padding bits in its output array) are included. */
2086 nunits = GET_MODE_SIZE (mode);
2087 bitsize = nunits * BITS_PER_UNIT;
2088 nelts = CEIL (bitsize, 32);
2089 units_per = 32 / BITS_PER_UNIT;
2091 real_to_target (data, &d, mode);
2093 /* Put out the first word with the specified alignment. */
2094 assemble_integer (GEN_INT (data[0]), MIN (nunits, units_per), align, 1);
2095 nunits -= units_per;
2097 /* Subsequent words need only 32-bit alignment. */
2098 align = min_align (align, 32);
2100 for (i = 1; i < nelts; i++)
2102 assemble_integer (GEN_INT (data[i]), MIN (nunits, units_per), align, 1);
2103 nunits -= units_per;
2107 /* Given an expression EXP with a constant value,
2108 reduce it to the sum of an assembler symbol and an integer.
2109 Store them both in the structure *VALUE.
2110 Abort if EXP does not reduce. */
2112 struct addr_const GTY(())
2114 rtx base;
2115 HOST_WIDE_INT offset;
2118 static void
2119 decode_addr_const (tree exp, struct addr_const *value)
2121 tree target = TREE_OPERAND (exp, 0);
2122 int offset = 0;
2123 rtx x;
2125 while (1)
2127 if (TREE_CODE (target) == COMPONENT_REF
2128 && host_integerp (byte_position (TREE_OPERAND (target, 1)), 0))
2131 offset += int_byte_position (TREE_OPERAND (target, 1));
2132 target = TREE_OPERAND (target, 0);
2134 else if (TREE_CODE (target) == ARRAY_REF
2135 || TREE_CODE (target) == ARRAY_RANGE_REF)
2137 offset += (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (target)), 1)
2138 * tree_low_cst (TREE_OPERAND (target, 1), 0));
2139 target = TREE_OPERAND (target, 0);
2141 else
2142 break;
2145 switch (TREE_CODE (target))
2147 case VAR_DECL:
2148 case FUNCTION_DECL:
2149 x = DECL_RTL (target);
2150 break;
2152 case LABEL_DECL:
2153 x = gen_rtx_MEM (FUNCTION_MODE,
2154 gen_rtx_LABEL_REF (VOIDmode, force_label_rtx (target)));
2155 break;
2157 case REAL_CST:
2158 case STRING_CST:
2159 case COMPLEX_CST:
2160 case CONSTRUCTOR:
2161 case INTEGER_CST:
2162 x = output_constant_def (target, 1);
2163 break;
2165 default:
2166 abort ();
2169 if (!MEM_P (x))
2170 abort ();
2171 x = XEXP (x, 0);
2173 value->base = x;
2174 value->offset = offset;
2177 /* Uniquize all constants that appear in memory.
2178 Each constant in memory thus far output is recorded
2179 in `const_desc_table'. */
2181 struct constant_descriptor_tree GTY(())
2183 /* A MEM for the constant. */
2184 rtx rtl;
2186 /* The value of the constant. */
2187 tree value;
2190 static GTY((param_is (struct constant_descriptor_tree)))
2191 htab_t const_desc_htab;
2193 static struct constant_descriptor_tree * build_constant_desc (tree);
2194 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2196 /* Compute a hash code for a constant expression. */
2198 static hashval_t
2199 const_desc_hash (const void *ptr)
2201 return const_hash_1 (((struct constant_descriptor_tree *)ptr)->value);
2204 static hashval_t
2205 const_hash_1 (const tree exp)
2207 const char *p;
2208 hashval_t hi;
2209 int len, i;
2210 enum tree_code code = TREE_CODE (exp);
2212 /* Either set P and LEN to the address and len of something to hash and
2213 exit the switch or return a value. */
2215 switch (code)
2217 case INTEGER_CST:
2218 p = (char *) &TREE_INT_CST (exp);
2219 len = sizeof TREE_INT_CST (exp);
2220 break;
2222 case REAL_CST:
2223 return real_hash (TREE_REAL_CST_PTR (exp));
2225 case STRING_CST:
2226 p = TREE_STRING_POINTER (exp);
2227 len = TREE_STRING_LENGTH (exp);
2228 break;
2230 case COMPLEX_CST:
2231 return (const_hash_1 (TREE_REALPART (exp)) * 5
2232 + const_hash_1 (TREE_IMAGPART (exp)));
2234 case CONSTRUCTOR:
2235 if (TREE_CODE (TREE_TYPE (exp)) == SET_TYPE)
2237 char *tmp;
2239 len = int_size_in_bytes (TREE_TYPE (exp));
2240 tmp = alloca (len);
2241 get_set_constructor_bytes (exp, (unsigned char *) tmp, len);
2242 p = tmp;
2243 break;
2245 else
2247 tree link;
2249 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2251 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link))
2252 if (TREE_VALUE (link))
2253 hi = hi * 603 + const_hash_1 (TREE_VALUE (link));
2255 return hi;
2258 case ADDR_EXPR:
2259 case FDESC_EXPR:
2261 struct addr_const value;
2263 decode_addr_const (exp, &value);
2264 if (GET_CODE (value.base) == SYMBOL_REF)
2266 /* Don't hash the address of the SYMBOL_REF;
2267 only use the offset and the symbol name. */
2268 hi = value.offset;
2269 p = XSTR (value.base, 0);
2270 for (i = 0; p[i] != 0; i++)
2271 hi = ((hi * 613) + (unsigned) (p[i]));
2273 else if (GET_CODE (value.base) == LABEL_REF)
2274 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13;
2275 else
2276 abort ();
2278 return hi;
2280 case PLUS_EXPR:
2281 case MINUS_EXPR:
2282 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2283 + const_hash_1 (TREE_OPERAND (exp, 1)));
2285 case NOP_EXPR:
2286 case CONVERT_EXPR:
2287 case NON_LVALUE_EXPR:
2288 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
2290 default:
2291 /* A language specific constant. Just hash the code. */
2292 return code;
2295 /* Compute hashing function. */
2296 hi = len;
2297 for (i = 0; i < len; i++)
2298 hi = ((hi * 613) + (unsigned) (p[i]));
2300 return hi;
2303 /* Wrapper of compare_constant, for the htab interface. */
2304 static int
2305 const_desc_eq (const void *p1, const void *p2)
2307 return compare_constant (((struct constant_descriptor_tree *)p1)->value,
2308 ((struct constant_descriptor_tree *)p2)->value);
2311 /* Compare t1 and t2, and return 1 only if they are known to result in
2312 the same bit pattern on output. */
2314 static int
2315 compare_constant (const tree t1, const tree t2)
2317 enum tree_code typecode;
2319 if (t1 == NULL_TREE)
2320 return t2 == NULL_TREE;
2321 if (t2 == NULL_TREE)
2322 return 0;
2324 if (TREE_CODE (t1) != TREE_CODE (t2))
2325 return 0;
2327 switch (TREE_CODE (t1))
2329 case INTEGER_CST:
2330 /* Integer constants are the same only if the same width of type. */
2331 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2332 return 0;
2333 return tree_int_cst_equal (t1, t2);
2335 case REAL_CST:
2336 /* Real constants are the same only if the same width of type. */
2337 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2338 return 0;
2340 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
2342 case STRING_CST:
2343 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2344 return 0;
2346 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
2347 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
2348 TREE_STRING_LENGTH (t1)));
2350 case COMPLEX_CST:
2351 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
2352 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
2354 case CONSTRUCTOR:
2355 typecode = TREE_CODE (TREE_TYPE (t1));
2356 if (typecode != TREE_CODE (TREE_TYPE (t2)))
2357 return 0;
2359 if (typecode == SET_TYPE)
2361 int len = int_size_in_bytes (TREE_TYPE (t2));
2362 unsigned char *tmp1, *tmp2;
2364 if (int_size_in_bytes (TREE_TYPE (t1)) != len)
2365 return 0;
2367 tmp1 = alloca (len);
2368 tmp2 = alloca (len);
2370 if (get_set_constructor_bytes (t1, tmp1, len) != NULL_TREE)
2371 return 0;
2372 if (get_set_constructor_bytes (t2, tmp2, len) != NULL_TREE)
2373 return 0;
2375 return memcmp (tmp1, tmp2, len) == 0;
2377 else
2379 tree l1, l2;
2381 if (typecode == ARRAY_TYPE)
2383 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
2384 /* For arrays, check that the sizes all match. */
2385 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
2386 || size_1 == -1
2387 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
2388 return 0;
2390 else
2392 /* For record and union constructors, require exact type
2393 equality. */
2394 if (TREE_TYPE (t1) != TREE_TYPE (t2))
2395 return 0;
2398 for (l1 = CONSTRUCTOR_ELTS (t1), l2 = CONSTRUCTOR_ELTS (t2);
2399 l1 && l2;
2400 l1 = TREE_CHAIN (l1), l2 = TREE_CHAIN (l2))
2402 /* Check that each value is the same... */
2403 if (! compare_constant (TREE_VALUE (l1), TREE_VALUE (l2)))
2404 return 0;
2405 /* ... and that they apply to the same fields! */
2406 if (typecode == ARRAY_TYPE)
2408 if (! compare_constant (TREE_PURPOSE (l1),
2409 TREE_PURPOSE (l2)))
2410 return 0;
2412 else
2414 if (TREE_PURPOSE (l1) != TREE_PURPOSE (l2))
2415 return 0;
2419 return l1 == NULL_TREE && l2 == NULL_TREE;
2422 case ADDR_EXPR:
2423 case FDESC_EXPR:
2425 struct addr_const value1, value2;
2427 decode_addr_const (t1, &value1);
2428 decode_addr_const (t2, &value2);
2429 return (value1.offset == value2.offset
2430 && strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
2433 case PLUS_EXPR:
2434 case MINUS_EXPR:
2435 case RANGE_EXPR:
2436 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
2437 && compare_constant(TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
2439 case NOP_EXPR:
2440 case CONVERT_EXPR:
2441 case NON_LVALUE_EXPR:
2442 case VIEW_CONVERT_EXPR:
2443 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
2445 default:
2447 tree nt1, nt2;
2448 nt1 = lang_hooks.expand_constant (t1);
2449 nt2 = lang_hooks.expand_constant (t2);
2450 if (nt1 != t1 || nt2 != t2)
2451 return compare_constant (nt1, nt2);
2452 else
2453 return 0;
2457 /* Should not get here. */
2458 abort ();
2461 /* Make a copy of the whole tree structure for a constant. This
2462 handles the same types of nodes that compare_constant handles. */
2464 static tree
2465 copy_constant (tree exp)
2467 switch (TREE_CODE (exp))
2469 case ADDR_EXPR:
2470 /* For ADDR_EXPR, we do not want to copy the decl whose address
2471 is requested. We do want to copy constants though. */
2472 if (CONSTANT_CLASS_P (TREE_OPERAND (exp, 0)))
2473 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
2474 copy_constant (TREE_OPERAND (exp, 0)));
2475 else
2476 return copy_node (exp);
2478 case INTEGER_CST:
2479 case REAL_CST:
2480 case STRING_CST:
2481 return copy_node (exp);
2483 case COMPLEX_CST:
2484 return build_complex (TREE_TYPE (exp),
2485 copy_constant (TREE_REALPART (exp)),
2486 copy_constant (TREE_IMAGPART (exp)));
2488 case PLUS_EXPR:
2489 case MINUS_EXPR:
2490 return build2 (TREE_CODE (exp), TREE_TYPE (exp),
2491 copy_constant (TREE_OPERAND (exp, 0)),
2492 copy_constant (TREE_OPERAND (exp, 1)));
2494 case NOP_EXPR:
2495 case CONVERT_EXPR:
2496 case NON_LVALUE_EXPR:
2497 case VIEW_CONVERT_EXPR:
2498 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
2499 copy_constant (TREE_OPERAND (exp, 0)));
2501 case CONSTRUCTOR:
2503 tree copy = copy_node (exp);
2504 tree list = copy_list (CONSTRUCTOR_ELTS (exp));
2505 tree tail;
2507 CONSTRUCTOR_ELTS (copy) = list;
2508 for (tail = list; tail; tail = TREE_CHAIN (tail))
2509 TREE_VALUE (tail) = copy_constant (TREE_VALUE (tail));
2510 if (TREE_CODE (TREE_TYPE (exp)) == SET_TYPE)
2511 for (tail = list; tail; tail = TREE_CHAIN (tail))
2512 TREE_PURPOSE (tail) = copy_constant (TREE_PURPOSE (tail));
2514 return copy;
2517 default:
2519 tree t;
2520 t = lang_hooks.expand_constant (exp);
2521 if (t != exp)
2522 return copy_constant (t);
2523 else
2524 abort ();
2529 /* Subroutine of output_constant_def:
2530 No constant equal to EXP is known to have been output.
2531 Make a constant descriptor to enter EXP in the hash table.
2532 Assign the label number and construct RTL to refer to the
2533 constant's location in memory.
2534 Caller is responsible for updating the hash table. */
2536 static struct constant_descriptor_tree *
2537 build_constant_desc (tree exp)
2539 rtx symbol;
2540 rtx rtl;
2541 char label[256];
2542 int labelno;
2543 struct constant_descriptor_tree *desc;
2545 desc = ggc_alloc (sizeof (*desc));
2546 desc->value = copy_constant (exp);
2548 /* Propagate marked-ness to copied constant. */
2549 if (flag_mudflap && mf_marked_p (exp))
2550 mf_mark (desc->value);
2552 /* Create a string containing the label name, in LABEL. */
2553 labelno = const_labelno++;
2554 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
2556 /* We have a symbol name; construct the SYMBOL_REF and the MEM. */
2557 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
2558 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2559 SYMBOL_REF_DECL (symbol) = desc->value;
2560 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
2562 rtl = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)), symbol);
2563 set_mem_attributes (rtl, exp, 1);
2564 set_mem_alias_set (rtl, 0);
2565 set_mem_alias_set (rtl, const_alias_set);
2567 /* Set flags or add text to the name to record information, such as
2568 that it is a local symbol. If the name is changed, the macro
2569 ASM_OUTPUT_LABELREF will have to know how to strip this
2570 information. This call might invalidate our local variable
2571 SYMBOL; we can't use it afterward. */
2573 targetm.encode_section_info (exp, rtl, true);
2575 desc->rtl = rtl;
2577 return desc;
2580 /* Return an rtx representing a reference to constant data in memory
2581 for the constant expression EXP.
2583 If assembler code for such a constant has already been output,
2584 return an rtx to refer to it.
2585 Otherwise, output such a constant in memory
2586 and generate an rtx for it.
2588 If DEFER is nonzero, this constant can be deferred and output only
2589 if referenced in the function after all optimizations.
2591 `const_desc_table' records which constants already have label strings. */
2594 output_constant_def (tree exp, int defer)
2596 struct constant_descriptor_tree *desc;
2597 struct constant_descriptor_tree key;
2598 void **loc;
2600 /* Look up EXP in the table of constant descriptors. If we didn't find
2601 it, create a new one. */
2602 key.value = exp;
2603 loc = htab_find_slot (const_desc_htab, &key, INSERT);
2605 desc = *loc;
2606 if (desc == 0)
2608 desc = build_constant_desc (exp);
2609 *loc = desc;
2612 maybe_output_constant_def_contents (desc, defer);
2613 return desc->rtl;
2616 /* Subroutine of output_constant_def: Decide whether or not we need to
2617 output the constant DESC now, and if so, do it. */
2618 static void
2619 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
2620 int defer)
2622 rtx symbol = XEXP (desc->rtl, 0);
2623 tree exp = desc->value;
2625 if (flag_syntax_only)
2626 return;
2628 if (TREE_ASM_WRITTEN (exp))
2629 /* Already output; don't do it again. */
2630 return;
2632 /* We can always defer constants as long as the context allows
2633 doing so. */
2634 if (defer)
2636 /* Increment n_deferred_constants if it exists. It needs to be at
2637 least as large as the number of constants actually referred to
2638 by the function. If it's too small we'll stop looking too early
2639 and fail to emit constants; if it's too large we'll only look
2640 through the entire function when we could have stopped earlier. */
2641 if (cfun)
2642 n_deferred_constants++;
2643 return;
2646 output_constant_def_contents (symbol);
2649 /* We must output the constant data referred to by SYMBOL; do so. */
2651 static void
2652 output_constant_def_contents (rtx symbol)
2654 tree exp = SYMBOL_REF_DECL (symbol);
2655 const char *label = XSTR (symbol, 0);
2656 HOST_WIDE_INT size;
2658 /* Make sure any other constants whose addresses appear in EXP
2659 are assigned label numbers. */
2660 int reloc = compute_reloc_for_constant (exp);
2662 /* Align the location counter as required by EXP's data type. */
2663 unsigned int align = TYPE_ALIGN (TREE_TYPE (exp));
2664 #ifdef CONSTANT_ALIGNMENT
2665 align = CONSTANT_ALIGNMENT (exp, align);
2666 #endif
2668 output_addressed_constants (exp);
2670 /* We are no longer deferring this constant. */
2671 TREE_ASM_WRITTEN (exp) = 1;
2673 if (IN_NAMED_SECTION (exp))
2674 named_section (exp, NULL, reloc);
2675 else
2676 targetm.asm_out.select_section (exp, reloc, align);
2678 if (align > BITS_PER_UNIT)
2680 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2683 size = int_size_in_bytes (TREE_TYPE (exp));
2684 if (TREE_CODE (exp) == STRING_CST)
2685 size = MAX (TREE_STRING_LENGTH (exp), size);
2687 /* Do any machine/system dependent processing of the constant. */
2688 #ifdef ASM_DECLARE_CONSTANT_NAME
2689 ASM_DECLARE_CONSTANT_NAME (asm_out_file, label, exp, size);
2690 #else
2691 /* Standard thing is just output label for the constant. */
2692 ASM_OUTPUT_LABEL (asm_out_file, label);
2693 #endif /* ASM_DECLARE_CONSTANT_NAME */
2695 /* Output the value of EXP. */
2696 output_constant (exp, size, align);
2697 if (flag_mudflap)
2698 mudflap_enqueue_constant (exp);
2701 /* Look up EXP in the table of constant descriptors. Return the rtl
2702 if it has been emitted, else null. */
2705 lookup_constant_def (tree exp)
2707 struct constant_descriptor_tree *desc;
2708 struct constant_descriptor_tree key;
2710 key.value = exp;
2711 desc = htab_find (const_desc_htab, &key);
2713 return (desc ? desc->rtl : NULL_RTX);
2716 /* Used in the hash tables to avoid outputting the same constant
2717 twice. Unlike 'struct constant_descriptor_tree', RTX constants
2718 are output once per function, not once per file. */
2719 /* ??? Only a few targets need per-function constant pools. Most
2720 can use one per-file pool. Should add a targetm bit to tell the
2721 difference. */
2723 struct rtx_constant_pool GTY(())
2725 /* Pointers to first and last constant in pool, as ordered by offset. */
2726 struct constant_descriptor_rtx *first;
2727 struct constant_descriptor_rtx *last;
2729 /* Hash facility for making memory-constants from constant rtl-expressions.
2730 It is used on RISC machines where immediate integer arguments and
2731 constant addresses are restricted so that such constants must be stored
2732 in memory. */
2733 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_htab;
2734 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_sym_htab;
2736 /* Current offset in constant pool (does not include any
2737 machine-specific header). */
2738 HOST_WIDE_INT offset;
2741 struct constant_descriptor_rtx GTY((chain_next ("%h.next")))
2743 struct constant_descriptor_rtx *next;
2744 rtx mem;
2745 rtx sym;
2746 rtx constant;
2747 HOST_WIDE_INT offset;
2748 hashval_t hash;
2749 enum machine_mode mode;
2750 unsigned int align;
2751 int labelno;
2752 int mark;
2755 /* Hash and compare functions for const_rtx_htab. */
2757 static hashval_t
2758 const_desc_rtx_hash (const void *ptr)
2760 const struct constant_descriptor_rtx *desc = ptr;
2761 return desc->hash;
2764 static int
2765 const_desc_rtx_eq (const void *a, const void *b)
2767 const struct constant_descriptor_rtx *x = a;
2768 const struct constant_descriptor_rtx *y = b;
2770 if (x->mode != y->mode)
2771 return 0;
2772 return rtx_equal_p (x->constant, y->constant);
2775 /* Hash and compare functions for const_rtx_sym_htab. */
2777 static hashval_t
2778 const_desc_rtx_sym_hash (const void *ptr)
2780 const struct constant_descriptor_rtx *desc = ptr;
2781 return htab_hash_string (XSTR (desc->sym, 0));
2784 static int
2785 const_desc_rtx_sym_eq (const void *a, const void *b)
2787 const struct constant_descriptor_rtx *x = a;
2788 const struct constant_descriptor_rtx *y = b;
2789 return XSTR (x->sym, 0) == XSTR (y->sym, 0);
2792 /* This is the worker function for const_rtx_hash, called via for_each_rtx. */
2794 static int
2795 const_rtx_hash_1 (rtx *xp, void *data)
2797 unsigned HOST_WIDE_INT hwi;
2798 enum machine_mode mode;
2799 enum rtx_code code;
2800 hashval_t h, *hp;
2801 rtx x;
2803 x = *xp;
2804 code = GET_CODE (x);
2805 mode = GET_MODE (x);
2806 h = (hashval_t) code * 1048573 + mode;
2808 switch (code)
2810 case CONST_INT:
2811 hwi = INTVAL (x);
2812 fold_hwi:
2814 const int shift = sizeof (hashval_t) * CHAR_BIT;
2815 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
2816 int i;
2818 h ^= (hashval_t) hwi;
2819 for (i = 1; i < n; ++i)
2821 hwi >>= shift;
2822 h ^= (hashval_t) hwi;
2825 break;
2827 case CONST_DOUBLE:
2828 if (mode == VOIDmode)
2830 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
2831 goto fold_hwi;
2833 else
2834 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
2835 break;
2837 case SYMBOL_REF:
2838 h ^= htab_hash_string (XSTR (x, 0));
2839 break;
2841 case LABEL_REF:
2842 h = h * 251 + CODE_LABEL_NUMBER (XEXP (x, 0));
2843 break;
2845 case UNSPEC:
2846 case UNSPEC_VOLATILE:
2847 h = h * 251 + XINT (x, 1);
2848 break;
2850 default:
2851 break;
2854 hp = data;
2855 *hp = *hp * 509 + h;
2856 return 0;
2859 /* Compute a hash value for X, which should be a constant. */
2861 static hashval_t
2862 const_rtx_hash (rtx x)
2864 hashval_t h = 0;
2865 for_each_rtx (&x, const_rtx_hash_1, &h);
2866 return h;
2870 /* Initialize constant pool hashing for a new function. */
2872 void
2873 init_varasm_status (struct function *f)
2875 struct varasm_status *p;
2876 struct rtx_constant_pool *pool;
2878 p = ggc_alloc (sizeof (struct varasm_status));
2879 f->varasm = p;
2881 pool = ggc_alloc (sizeof (struct rtx_constant_pool));
2882 p->pool = pool;
2883 p->deferred_constants = 0;
2885 pool->const_rtx_htab = htab_create_ggc (31, const_desc_rtx_hash,
2886 const_desc_rtx_eq, NULL);
2887 pool->const_rtx_sym_htab = htab_create_ggc (31, const_desc_rtx_sym_hash,
2888 const_desc_rtx_sym_eq, NULL);
2889 pool->first = pool->last = NULL;
2890 pool->offset = 0;
2893 /* Given a MINUS expression, simplify it if both sides
2894 include the same symbol. */
2897 simplify_subtraction (rtx x)
2899 rtx r = simplify_rtx (x);
2900 return r ? r : x;
2903 /* Given a constant rtx X, make (or find) a memory constant for its value
2904 and return a MEM rtx to refer to it in memory. */
2907 force_const_mem (enum machine_mode mode, rtx x)
2909 struct constant_descriptor_rtx *desc, tmp;
2910 struct rtx_constant_pool *pool = cfun->varasm->pool;
2911 char label[256];
2912 rtx def, symbol;
2913 hashval_t hash;
2914 unsigned int align;
2915 void **slot;
2917 /* If we're not allowed to drop X into the constant pool, don't. */
2918 if (targetm.cannot_force_const_mem (x))
2919 return NULL_RTX;
2921 /* Lookup the value in the hashtable. */
2922 tmp.constant = x;
2923 tmp.mode = mode;
2924 hash = const_rtx_hash (x);
2925 slot = htab_find_slot_with_hash (pool->const_rtx_htab, &tmp, hash, INSERT);
2926 desc = *slot;
2928 /* If the constant was already present, return its memory. */
2929 if (desc)
2930 return copy_rtx (desc->mem);
2932 /* Otherwise, create a new descriptor. */
2933 desc = ggc_alloc (sizeof (*desc));
2934 *slot = desc;
2936 /* Align the location counter as required by EXP's data type. */
2937 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
2938 #ifdef CONSTANT_ALIGNMENT
2940 tree type = lang_hooks.types.type_for_mode (mode, 0);
2941 if (type != NULL_TREE)
2942 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
2944 #endif
2946 pool->offset += (align / BITS_PER_UNIT) - 1;
2947 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
2949 desc->next = NULL;
2950 desc->constant = tmp.constant;
2951 desc->offset = pool->offset;
2952 desc->hash = hash;
2953 desc->mode = mode;
2954 desc->align = align;
2955 desc->labelno = const_labelno;
2956 desc->mark = 0;
2958 pool->offset += GET_MODE_SIZE (mode);
2959 if (pool->last)
2960 pool->last->next = desc;
2961 else
2962 pool->first = pool->last = desc;
2963 pool->last = desc;
2965 /* Create a string containing the label name, in LABEL. */
2966 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
2967 ++const_labelno;
2969 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
2970 the constants pool. */
2971 desc->sym = symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
2972 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2973 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
2974 current_function_uses_const_pool = 1;
2976 /* Insert the descriptor into the symbol cross-reference table too. */
2977 slot = htab_find_slot (pool->const_rtx_sym_htab, desc, INSERT);
2978 if (*slot)
2979 abort ();
2980 *slot = desc;
2982 /* Construct the MEM. */
2983 desc->mem = def = gen_const_mem (mode, symbol);
2984 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
2986 /* If we're dropping a label to the constant pool, make sure we
2987 don't delete it. */
2988 if (GET_CODE (x) == LABEL_REF)
2989 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
2991 return copy_rtx (def);
2994 /* Given a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true, return a pointer to
2995 the corresponding constant_descriptor_rtx structure. */
2997 static struct constant_descriptor_rtx *
2998 find_pool_constant (struct rtx_constant_pool *pool, rtx sym)
3000 struct constant_descriptor_rtx tmp;
3001 tmp.sym = sym;
3002 return htab_find (pool->const_rtx_sym_htab, &tmp);
3005 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3008 get_pool_constant (rtx addr)
3010 return find_pool_constant (cfun->varasm->pool, addr)->constant;
3013 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3014 and whether it has been output or not. */
3017 get_pool_constant_mark (rtx addr, bool *pmarked)
3019 struct constant_descriptor_rtx *desc;
3021 desc = find_pool_constant (cfun->varasm->pool, addr);
3022 *pmarked = (desc->mark != 0);
3023 return desc->constant;
3026 /* Likewise, but for the constant pool of a specific function. */
3029 get_pool_constant_for_function (struct function *f, rtx addr)
3031 return find_pool_constant (f->varasm->pool, addr)->constant;
3034 /* Similar, return the mode. */
3036 enum machine_mode
3037 get_pool_mode (rtx addr)
3039 return find_pool_constant (cfun->varasm->pool, addr)->mode;
3042 enum machine_mode
3043 get_pool_mode_for_function (struct function *f, rtx addr)
3045 return find_pool_constant (f->varasm->pool, addr)->mode;
3048 /* Similar, return the offset in the constant pool. */
3051 get_pool_offset (rtx addr)
3053 return find_pool_constant (cfun->varasm->pool, addr)->offset;
3056 /* Return the size of the constant pool. */
3059 get_pool_size (void)
3061 return cfun->varasm->pool->offset;
3064 /* Worker function for output_constant_pool_1. Emit assembly for X
3065 in MODE with known alignment ALIGN. */
3067 static void
3068 output_constant_pool_2 (enum machine_mode mode, rtx x, unsigned int align)
3070 switch (GET_MODE_CLASS (mode))
3072 case MODE_FLOAT:
3073 if (GET_CODE (x) != CONST_DOUBLE)
3074 abort ();
3075 else
3077 REAL_VALUE_TYPE r;
3078 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3079 assemble_real (r, mode, align);
3081 break;
3083 case MODE_INT:
3084 case MODE_PARTIAL_INT:
3085 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3086 break;
3088 case MODE_VECTOR_FLOAT:
3089 case MODE_VECTOR_INT:
3091 int i, units;
3092 enum machine_mode submode = GET_MODE_INNER (mode);
3093 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3095 if (GET_CODE (x) != CONST_VECTOR)
3096 abort ();
3097 units = CONST_VECTOR_NUNITS (x);
3099 for (i = 0; i < units; i++)
3101 rtx elt = CONST_VECTOR_ELT (x, i);
3102 output_constant_pool_2 (submode, elt, i ? subalign : align);
3105 break;
3107 default:
3108 abort ();
3112 /* Worker function for output_constant_pool. Emit POOL. */
3114 static void
3115 output_constant_pool_1 (struct constant_descriptor_rtx *desc)
3117 rtx x, tmp;
3119 if (!desc->mark)
3120 return;
3121 x = desc->constant;
3123 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3124 whose CODE_LABEL has been deleted. This can occur if a jump table
3125 is eliminated by optimization. If so, write a constant of zero
3126 instead. Note that this can also happen by turning the
3127 CODE_LABEL into a NOTE. */
3128 /* ??? This seems completely and utterly wrong. Certainly it's
3129 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3130 functioning even with INSN_DELETED_P and friends. */
3132 tmp = x;
3133 switch (GET_CODE (x))
3135 case CONST:
3136 if (GET_CODE (XEXP (x, 0)) != PLUS
3137 || GET_CODE (XEXP (XEXP (x, 0), 0)) != LABEL_REF)
3138 break;
3139 tmp = XEXP (XEXP (x, 0), 0);
3140 /* FALLTHRU */
3142 case LABEL_REF:
3143 tmp = XEXP (x, 0);
3144 if (INSN_DELETED_P (tmp)
3145 || (NOTE_P (tmp)
3146 && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_DELETED))
3148 abort ();
3149 x = const0_rtx;
3151 break;
3153 default:
3154 break;
3157 /* First switch to correct section. */
3158 targetm.asm_out.select_rtx_section (desc->mode, x, desc->align);
3160 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3161 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3162 desc->align, desc->labelno, done);
3163 #endif
3165 assemble_align (desc->align);
3167 /* Output the label. */
3168 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3170 /* Output the data. */
3171 output_constant_pool_2 (desc->mode, x, desc->align);
3173 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3174 sections have proper size. */
3175 if (desc->align > GET_MODE_BITSIZE (desc->mode)
3176 && in_section == in_named
3177 && get_named_section_flags (in_named_name) & SECTION_MERGE)
3178 assemble_align (desc->align);
3180 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3181 done:
3182 #endif
3183 return;
3186 /* Given a SYMBOL_REF CURRENT_RTX, mark it and all constants it refers
3187 to as used. Emit referenced deferred strings. This function can
3188 be used with for_each_rtx to mark all SYMBOL_REFs in an rtx. */
3190 static int
3191 mark_constant (rtx *current_rtx, void *data)
3193 struct rtx_constant_pool *pool = data;
3194 rtx x = *current_rtx;
3196 if (x == NULL_RTX || GET_CODE (x) != SYMBOL_REF)
3197 return 0;
3199 if (CONSTANT_POOL_ADDRESS_P (x))
3201 struct constant_descriptor_rtx *desc = find_pool_constant (pool, x);
3202 if (desc->mark == 0)
3204 desc->mark = 1;
3205 for_each_rtx (&desc->constant, mark_constant, pool);
3208 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3210 tree exp = SYMBOL_REF_DECL (x);
3211 if (!TREE_ASM_WRITTEN (exp))
3213 n_deferred_constants--;
3214 output_constant_def_contents (x);
3218 return -1;
3221 /* Look through appropriate parts of INSN, marking all entries in the
3222 constant pool which are actually being used. Entries that are only
3223 referenced by other constants are also marked as used. Emit
3224 deferred strings that are used. */
3226 static void
3227 mark_constants (struct rtx_constant_pool *pool, rtx insn)
3229 if (!INSN_P (insn))
3230 return;
3232 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3233 insns, not any notes that may be attached. We don't want to mark
3234 a constant just because it happens to appear in a REG_EQUIV note. */
3235 if (GET_CODE (PATTERN (insn)) == SEQUENCE)
3237 rtx seq = PATTERN (insn);
3238 int i, n = XVECLEN (seq, 0);
3239 for (i = 0; i < n; ++i)
3241 rtx subinsn = XVECEXP (seq, 0, i);
3242 if (INSN_P (subinsn))
3243 for_each_rtx (&PATTERN (subinsn), mark_constant, pool);
3246 else
3247 for_each_rtx (&PATTERN (insn), mark_constant, pool);
3250 /* Look through the instructions for this function, and mark all the
3251 entries in POOL which are actually being used. Emit deferred constants
3252 which have indeed been used. */
3254 static void
3255 mark_constant_pool (struct rtx_constant_pool *pool)
3257 rtx insn, link;
3259 if (pool->first == 0 && n_deferred_constants == 0)
3260 return;
3262 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3263 mark_constants (pool, insn);
3265 for (link = current_function_epilogue_delay_list;
3266 link;
3267 link = XEXP (link, 1))
3268 mark_constants (pool, XEXP (link, 0));
3271 /* Write all the constants in the constant pool. */
3273 void
3274 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
3275 tree fndecl ATTRIBUTE_UNUSED)
3277 struct rtx_constant_pool *pool = cfun->varasm->pool;
3278 struct constant_descriptor_rtx *desc;
3280 /* It is possible for gcc to call force_const_mem and then to later
3281 discard the instructions which refer to the constant. In such a
3282 case we do not need to output the constant. */
3283 mark_constant_pool (pool);
3285 #ifdef ASM_OUTPUT_POOL_PROLOGUE
3286 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
3287 #endif
3289 for (desc = pool->first; desc ; desc = desc->next)
3290 output_constant_pool_1 (desc);
3292 #ifdef ASM_OUTPUT_POOL_EPILOGUE
3293 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
3294 #endif
3297 /* Determine what kind of relocations EXP may need. */
3300 compute_reloc_for_constant (tree exp)
3302 int reloc = 0, reloc2;
3303 tree tem;
3305 /* Give the front-end a chance to convert VALUE to something that
3306 looks more like a constant to the back-end. */
3307 exp = lang_hooks.expand_constant (exp);
3309 switch (TREE_CODE (exp))
3311 case ADDR_EXPR:
3312 case FDESC_EXPR:
3313 /* Go inside any operations that get_inner_reference can handle and see
3314 if what's inside is a constant: no need to do anything here for
3315 addresses of variables or functions. */
3316 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
3317 tem = TREE_OPERAND (tem, 0))
3320 if (TREE_PUBLIC (tem))
3321 reloc |= 2;
3322 else
3323 reloc |= 1;
3324 break;
3326 case PLUS_EXPR:
3327 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3328 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
3329 break;
3331 case MINUS_EXPR:
3332 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3333 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
3334 /* The difference of two local labels is computable at link time. */
3335 if (reloc == 1 && reloc2 == 1)
3336 reloc = 0;
3337 else
3338 reloc |= reloc2;
3339 break;
3341 case NOP_EXPR:
3342 case CONVERT_EXPR:
3343 case NON_LVALUE_EXPR:
3344 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3345 break;
3347 case CONSTRUCTOR:
3348 for (tem = CONSTRUCTOR_ELTS (exp); tem; tem = TREE_CHAIN (tem))
3349 if (TREE_VALUE (tem) != 0)
3350 reloc |= compute_reloc_for_constant (TREE_VALUE (tem));
3352 break;
3354 default:
3355 break;
3357 return reloc;
3360 /* Find all the constants whose addresses are referenced inside of EXP,
3361 and make sure assembler code with a label has been output for each one.
3362 Indicate whether an ADDR_EXPR has been encountered. */
3364 static void
3365 output_addressed_constants (tree exp)
3367 tree tem;
3369 /* Give the front-end a chance to convert VALUE to something that
3370 looks more like a constant to the back-end. */
3371 exp = lang_hooks.expand_constant (exp);
3373 switch (TREE_CODE (exp))
3375 case ADDR_EXPR:
3376 case FDESC_EXPR:
3377 /* Go inside any operations that get_inner_reference can handle and see
3378 if what's inside is a constant: no need to do anything here for
3379 addresses of variables or functions. */
3380 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
3381 tem = TREE_OPERAND (tem, 0))
3384 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
3385 output_constant_def (tem, 0);
3386 break;
3388 case PLUS_EXPR:
3389 case MINUS_EXPR:
3390 output_addressed_constants (TREE_OPERAND (exp, 1));
3391 /* Fall through. */
3393 case NOP_EXPR:
3394 case CONVERT_EXPR:
3395 case NON_LVALUE_EXPR:
3396 output_addressed_constants (TREE_OPERAND (exp, 0));
3397 break;
3399 case CONSTRUCTOR:
3400 for (tem = CONSTRUCTOR_ELTS (exp); tem; tem = TREE_CHAIN (tem))
3401 if (TREE_VALUE (tem) != 0)
3402 output_addressed_constants (TREE_VALUE (tem));
3404 break;
3406 default:
3407 break;
3411 /* Return nonzero if VALUE is a valid constant-valued expression
3412 for use in initializing a static variable; one that can be an
3413 element of a "constant" initializer.
3415 Return null_pointer_node if the value is absolute;
3416 if it is relocatable, return the variable that determines the relocation.
3417 We assume that VALUE has been folded as much as possible;
3418 therefore, we do not need to check for such things as
3419 arithmetic-combinations of integers. */
3421 tree
3422 initializer_constant_valid_p (tree value, tree endtype)
3424 /* Give the front-end a chance to convert VALUE to something that
3425 looks more like a constant to the back-end. */
3426 value = lang_hooks.expand_constant (value);
3428 switch (TREE_CODE (value))
3430 case CONSTRUCTOR:
3431 if ((TREE_CODE (TREE_TYPE (value)) == UNION_TYPE
3432 || TREE_CODE (TREE_TYPE (value)) == RECORD_TYPE)
3433 && TREE_CONSTANT (value)
3434 && CONSTRUCTOR_ELTS (value))
3436 tree elt;
3437 bool absolute = true;
3439 for (elt = CONSTRUCTOR_ELTS (value); elt; elt = TREE_CHAIN (elt))
3441 tree reloc;
3442 value = TREE_VALUE (elt);
3443 reloc = initializer_constant_valid_p (value, TREE_TYPE (value));
3444 if (!reloc)
3445 return NULL_TREE;
3446 if (reloc != null_pointer_node)
3447 absolute = false;
3449 /* For a non-absolute relocation, there is no single
3450 variable that can be "the variable that determines the
3451 relocation." */
3452 return absolute ? null_pointer_node : error_mark_node;
3455 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
3457 case INTEGER_CST:
3458 case VECTOR_CST:
3459 case REAL_CST:
3460 case STRING_CST:
3461 case COMPLEX_CST:
3462 return null_pointer_node;
3464 case ADDR_EXPR:
3465 case FDESC_EXPR:
3466 value = staticp (TREE_OPERAND (value, 0));
3467 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out to
3468 be a constant, this is old-skool offsetof-like nonsense. */
3469 if (value
3470 && TREE_CODE (value) == INDIRECT_REF
3471 && TREE_CONSTANT (TREE_OPERAND (value, 0)))
3472 return null_pointer_node;
3473 return value;
3475 case VIEW_CONVERT_EXPR:
3476 case NON_LVALUE_EXPR:
3477 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3479 case CONVERT_EXPR:
3480 case NOP_EXPR:
3481 /* Allow conversions between pointer types. */
3482 if (POINTER_TYPE_P (TREE_TYPE (value))
3483 && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3484 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3486 /* Allow conversions between real types. */
3487 if (FLOAT_TYPE_P (TREE_TYPE (value))
3488 && FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3489 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3491 /* Allow length-preserving conversions between integer types. */
3492 if (INTEGRAL_TYPE_P (TREE_TYPE (value))
3493 && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0)))
3494 && (TYPE_PRECISION (TREE_TYPE (value))
3495 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0)))))
3496 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3498 /* Allow conversions between other integer types only if
3499 explicit value. */
3500 if (INTEGRAL_TYPE_P (TREE_TYPE (value))
3501 && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3503 tree inner = initializer_constant_valid_p (TREE_OPERAND (value, 0),
3504 endtype);
3505 if (inner == null_pointer_node)
3506 return null_pointer_node;
3507 break;
3510 /* Allow (int) &foo provided int is as wide as a pointer. */
3511 if (INTEGRAL_TYPE_P (TREE_TYPE (value))
3512 && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0)))
3513 && (TYPE_PRECISION (TREE_TYPE (value))
3514 >= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0)))))
3515 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
3516 endtype);
3518 /* Likewise conversions from int to pointers, but also allow
3519 conversions from 0. */
3520 if ((POINTER_TYPE_P (TREE_TYPE (value))
3521 || TREE_CODE (TREE_TYPE (value)) == OFFSET_TYPE)
3522 && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3524 if (integer_zerop (TREE_OPERAND (value, 0)))
3525 return null_pointer_node;
3526 else if (TYPE_PRECISION (TREE_TYPE (value))
3527 <= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0))))
3528 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
3529 endtype);
3532 /* Allow conversions to struct or union types if the value
3533 inside is okay. */
3534 if (TREE_CODE (TREE_TYPE (value)) == RECORD_TYPE
3535 || TREE_CODE (TREE_TYPE (value)) == UNION_TYPE)
3536 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
3537 endtype);
3538 break;
3540 case PLUS_EXPR:
3541 if (! INTEGRAL_TYPE_P (endtype)
3542 || TYPE_PRECISION (endtype) >= POINTER_SIZE)
3544 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0),
3545 endtype);
3546 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1),
3547 endtype);
3548 /* If either term is absolute, use the other terms relocation. */
3549 if (valid0 == null_pointer_node)
3550 return valid1;
3551 if (valid1 == null_pointer_node)
3552 return valid0;
3554 break;
3556 case MINUS_EXPR:
3557 if (! INTEGRAL_TYPE_P (endtype)
3558 || TYPE_PRECISION (endtype) >= POINTER_SIZE)
3560 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0),
3561 endtype);
3562 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1),
3563 endtype);
3564 /* Win if second argument is absolute. */
3565 if (valid1 == null_pointer_node)
3566 return valid0;
3567 /* Win if both arguments have the same relocation.
3568 Then the value is absolute. */
3569 if (valid0 == valid1 && valid0 != 0)
3570 return null_pointer_node;
3572 /* Since GCC guarantees that string constants are unique in the
3573 generated code, a subtraction between two copies of the same
3574 constant string is absolute. */
3575 if (valid0 && TREE_CODE (valid0) == STRING_CST
3576 && valid1 && TREE_CODE (valid1) == STRING_CST
3577 && operand_equal_p (valid0, valid1, 1))
3578 return null_pointer_node;
3581 /* Support narrowing differences. */
3582 if (INTEGRAL_TYPE_P (endtype))
3584 tree op0, op1;
3586 op0 = TREE_OPERAND (value, 0);
3587 op1 = TREE_OPERAND (value, 1);
3589 /* Like STRIP_NOPS except allow the operand mode to widen.
3590 This works around a feature of fold that simplifies
3591 (int)(p1 - p2) to ((int)p1 - (int)p2) under the theory
3592 that the narrower operation is cheaper. */
3594 while (TREE_CODE (op0) == NOP_EXPR
3595 || TREE_CODE (op0) == CONVERT_EXPR
3596 || TREE_CODE (op0) == NON_LVALUE_EXPR)
3598 tree inner = TREE_OPERAND (op0, 0);
3599 if (inner == error_mark_node
3600 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
3601 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
3602 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
3603 break;
3604 op0 = inner;
3607 while (TREE_CODE (op1) == NOP_EXPR
3608 || TREE_CODE (op1) == CONVERT_EXPR
3609 || TREE_CODE (op1) == NON_LVALUE_EXPR)
3611 tree inner = TREE_OPERAND (op1, 0);
3612 if (inner == error_mark_node
3613 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
3614 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
3615 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
3616 break;
3617 op1 = inner;
3620 op0 = initializer_constant_valid_p (op0, endtype);
3621 op1 = initializer_constant_valid_p (op1, endtype);
3623 /* Both initializers must be known. */
3624 if (op0 && op1)
3626 if (op0 == op1)
3627 return null_pointer_node;
3629 /* Support differences between labels. */
3630 if (TREE_CODE (op0) == LABEL_DECL
3631 && TREE_CODE (op1) == LABEL_DECL)
3632 return null_pointer_node;
3634 if (TREE_CODE (op0) == STRING_CST
3635 && TREE_CODE (op1) == STRING_CST
3636 && operand_equal_p (op0, op1, 1))
3637 return null_pointer_node;
3640 break;
3642 default:
3643 break;
3646 return 0;
3649 /* Output assembler code for constant EXP to FILE, with no label.
3650 This includes the pseudo-op such as ".int" or ".byte", and a newline.
3651 Assumes output_addressed_constants has been done on EXP already.
3653 Generate exactly SIZE bytes of assembler data, padding at the end
3654 with zeros if necessary. SIZE must always be specified.
3656 SIZE is important for structure constructors,
3657 since trailing members may have been omitted from the constructor.
3658 It is also important for initialization of arrays from string constants
3659 since the full length of the string constant might not be wanted.
3660 It is also needed for initialization of unions, where the initializer's
3661 type is just one member, and that may not be as long as the union.
3663 There a case in which we would fail to output exactly SIZE bytes:
3664 for a structure constructor that wants to produce more than SIZE bytes.
3665 But such constructors will never be generated for any possible input.
3667 ALIGN is the alignment of the data in bits. */
3669 void
3670 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align)
3672 enum tree_code code;
3673 unsigned HOST_WIDE_INT thissize;
3675 /* Some front-ends use constants other than the standard language-independent
3676 varieties, but which may still be output directly. Give the front-end a
3677 chance to convert EXP to a language-independent representation. */
3678 exp = lang_hooks.expand_constant (exp);
3680 if (size == 0 || flag_syntax_only)
3681 return;
3683 /* Eliminate any conversions since we'll be outputting the underlying
3684 constant. */
3685 while (TREE_CODE (exp) == NOP_EXPR || TREE_CODE (exp) == CONVERT_EXPR
3686 || TREE_CODE (exp) == NON_LVALUE_EXPR
3687 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
3688 exp = TREE_OPERAND (exp, 0);
3690 code = TREE_CODE (TREE_TYPE (exp));
3691 thissize = int_size_in_bytes (TREE_TYPE (exp));
3693 /* Allow a constructor with no elements for any data type.
3694 This means to fill the space with zeros. */
3695 if (TREE_CODE (exp) == CONSTRUCTOR && CONSTRUCTOR_ELTS (exp) == 0)
3697 assemble_zeros (size);
3698 return;
3701 if (TREE_CODE (exp) == FDESC_EXPR)
3703 #ifdef ASM_OUTPUT_FDESC
3704 HOST_WIDE_INT part = tree_low_cst (TREE_OPERAND (exp, 1), 0);
3705 tree decl = TREE_OPERAND (exp, 0);
3706 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
3707 #else
3708 abort ();
3709 #endif
3710 return;
3713 /* Now output the underlying data. If we've handling the padding, return.
3714 Otherwise, break and ensure SIZE is the size written. */
3715 switch (code)
3717 case CHAR_TYPE:
3718 case BOOLEAN_TYPE:
3719 case INTEGER_TYPE:
3720 case ENUMERAL_TYPE:
3721 case POINTER_TYPE:
3722 case REFERENCE_TYPE:
3723 case OFFSET_TYPE:
3724 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
3725 EXPAND_INITIALIZER),
3726 MIN (size, thissize), align, 0))
3727 error ("initializer for integer value is too complicated");
3728 break;
3730 case REAL_TYPE:
3731 if (TREE_CODE (exp) != REAL_CST)
3732 error ("initializer for floating value is not a floating constant");
3734 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)), align);
3735 break;
3737 case COMPLEX_TYPE:
3738 output_constant (TREE_REALPART (exp), thissize / 2, align);
3739 output_constant (TREE_IMAGPART (exp), thissize / 2,
3740 min_align (align, BITS_PER_UNIT * (thissize / 2)));
3741 break;
3743 case ARRAY_TYPE:
3744 case VECTOR_TYPE:
3745 if (TREE_CODE (exp) == CONSTRUCTOR)
3747 output_constructor (exp, size, align);
3748 return;
3750 else if (TREE_CODE (exp) == STRING_CST)
3752 thissize = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp),
3753 size);
3754 assemble_string (TREE_STRING_POINTER (exp), thissize);
3756 else if (TREE_CODE (exp) == VECTOR_CST)
3758 int elt_size;
3759 tree link;
3760 unsigned int nalign;
3761 enum machine_mode inner;
3763 inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
3764 nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
3766 elt_size = GET_MODE_SIZE (inner);
3768 link = TREE_VECTOR_CST_ELTS (exp);
3769 output_constant (TREE_VALUE (link), elt_size, align);
3770 while ((link = TREE_CHAIN (link)) != NULL)
3771 output_constant (TREE_VALUE (link), elt_size, nalign);
3773 else
3774 abort ();
3775 break;
3777 case RECORD_TYPE:
3778 case UNION_TYPE:
3779 if (TREE_CODE (exp) == CONSTRUCTOR)
3780 output_constructor (exp, size, align);
3781 else
3782 abort ();
3783 return;
3785 case SET_TYPE:
3786 if (TREE_CODE (exp) == INTEGER_CST)
3787 assemble_integer (expand_expr (exp, NULL_RTX,
3788 VOIDmode, EXPAND_INITIALIZER),
3789 thissize, align, 1);
3790 else if (TREE_CODE (exp) == CONSTRUCTOR)
3792 unsigned char *buffer = alloca (thissize);
3793 if (get_set_constructor_bytes (exp, buffer, thissize))
3794 abort ();
3795 assemble_string ((char *) buffer, thissize);
3797 else
3798 error ("unknown set constructor type");
3799 return;
3801 case ERROR_MARK:
3802 return;
3804 default:
3805 abort ();
3808 if (size > thissize)
3809 assemble_zeros (size - thissize);
3813 /* Subroutine of output_constructor, used for computing the size of
3814 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
3815 type with an unspecified upper bound. */
3817 static unsigned HOST_WIDE_INT
3818 array_size_for_constructor (tree val)
3820 tree max_index, i;
3822 /* This code used to attempt to handle string constants that are not
3823 arrays of single-bytes, but nothing else does, so there's no point in
3824 doing it here. */
3825 if (TREE_CODE (val) == STRING_CST)
3826 return TREE_STRING_LENGTH (val);
3828 max_index = NULL_TREE;
3829 for (i = CONSTRUCTOR_ELTS (val); i; i = TREE_CHAIN (i))
3831 tree index = TREE_PURPOSE (i);
3833 if (TREE_CODE (index) == RANGE_EXPR)
3834 index = TREE_OPERAND (index, 1);
3835 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
3836 max_index = index;
3839 if (max_index == NULL_TREE)
3840 return 0;
3842 /* Compute the total number of array elements. */
3843 i = size_binop (MINUS_EXPR, convert (sizetype, max_index),
3844 convert (sizetype,
3845 TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)))));
3846 i = size_binop (PLUS_EXPR, i, convert (sizetype, integer_one_node));
3848 /* Multiply by the array element unit size to find number of bytes. */
3849 i = size_binop (MULT_EXPR, i, TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
3851 return tree_low_cst (i, 1);
3854 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
3855 Generate at least SIZE bytes, padding if necessary. */
3857 static void
3858 output_constructor (tree exp, unsigned HOST_WIDE_INT size,
3859 unsigned int align)
3861 tree type = TREE_TYPE (exp);
3862 tree link, field = 0;
3863 tree min_index = 0;
3864 /* Number of bytes output or skipped so far.
3865 In other words, current position within the constructor. */
3866 HOST_WIDE_INT total_bytes = 0;
3867 /* Nonzero means BYTE contains part of a byte, to be output. */
3868 int byte_buffer_in_use = 0;
3869 int byte = 0;
3871 if (HOST_BITS_PER_WIDE_INT < BITS_PER_UNIT)
3872 abort ();
3874 if (TREE_CODE (type) == RECORD_TYPE)
3875 field = TYPE_FIELDS (type);
3877 if (TREE_CODE (type) == ARRAY_TYPE
3878 && TYPE_DOMAIN (type) != 0)
3879 min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (type));
3881 /* As LINK goes through the elements of the constant,
3882 FIELD goes through the structure fields, if the constant is a structure.
3883 if the constant is a union, then we override this,
3884 by getting the field from the TREE_LIST element.
3885 But the constant could also be an array. Then FIELD is zero.
3887 There is always a maximum of one element in the chain LINK for unions
3888 (even if the initializer in a source program incorrectly contains
3889 more one). */
3890 for (link = CONSTRUCTOR_ELTS (exp);
3891 link;
3892 link = TREE_CHAIN (link),
3893 field = field ? TREE_CHAIN (field) : 0)
3895 tree val = TREE_VALUE (link);
3896 tree index = 0;
3898 /* The element in a union constructor specifies the proper field
3899 or index. */
3900 if ((TREE_CODE (type) == RECORD_TYPE || TREE_CODE (type) == UNION_TYPE
3901 || TREE_CODE (type) == QUAL_UNION_TYPE)
3902 && TREE_PURPOSE (link) != 0)
3903 field = TREE_PURPOSE (link);
3905 else if (TREE_CODE (type) == ARRAY_TYPE)
3906 index = TREE_PURPOSE (link);
3908 #ifdef ASM_COMMENT_START
3909 if (field && flag_verbose_asm)
3910 fprintf (asm_out_file, "%s %s:\n",
3911 ASM_COMMENT_START,
3912 DECL_NAME (field)
3913 ? IDENTIFIER_POINTER (DECL_NAME (field))
3914 : "<anonymous>");
3915 #endif
3917 /* Eliminate the marker that makes a cast not be an lvalue. */
3918 if (val != 0)
3919 STRIP_NOPS (val);
3921 if (index && TREE_CODE (index) == RANGE_EXPR)
3923 unsigned HOST_WIDE_INT fieldsize
3924 = int_size_in_bytes (TREE_TYPE (type));
3925 HOST_WIDE_INT lo_index = tree_low_cst (TREE_OPERAND (index, 0), 0);
3926 HOST_WIDE_INT hi_index = tree_low_cst (TREE_OPERAND (index, 1), 0);
3927 HOST_WIDE_INT index;
3928 unsigned int align2 = min_align (align, fieldsize * BITS_PER_UNIT);
3930 for (index = lo_index; index <= hi_index; index++)
3932 /* Output the element's initial value. */
3933 if (val == 0)
3934 assemble_zeros (fieldsize);
3935 else
3936 output_constant (val, fieldsize, align2);
3938 /* Count its size. */
3939 total_bytes += fieldsize;
3942 else if (field == 0 || !DECL_BIT_FIELD (field))
3944 /* An element that is not a bit-field. */
3946 unsigned HOST_WIDE_INT fieldsize;
3947 /* Since this structure is static,
3948 we know the positions are constant. */
3949 HOST_WIDE_INT pos = field ? int_byte_position (field) : 0;
3950 unsigned int align2;
3952 if (index != 0)
3953 pos = (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (val)), 1)
3954 * (tree_low_cst (index, 0) - tree_low_cst (min_index, 0)));
3956 /* Output any buffered-up bit-fields preceding this element. */
3957 if (byte_buffer_in_use)
3959 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
3960 total_bytes++;
3961 byte_buffer_in_use = 0;
3964 /* Advance to offset of this element.
3965 Note no alignment needed in an array, since that is guaranteed
3966 if each element has the proper size. */
3967 if ((field != 0 || index != 0) && pos != total_bytes)
3969 assemble_zeros (pos - total_bytes);
3970 total_bytes = pos;
3973 /* Find the alignment of this element. */
3974 align2 = min_align (align, BITS_PER_UNIT * pos);
3976 /* Determine size this element should occupy. */
3977 if (field)
3979 fieldsize = 0;
3981 /* If this is an array with an unspecified upper bound,
3982 the initializer determines the size. */
3983 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
3984 but we cannot do this until the deprecated support for
3985 initializing zero-length array members is removed. */
3986 if (TREE_CODE (TREE_TYPE (field)) == ARRAY_TYPE
3987 && TYPE_DOMAIN (TREE_TYPE (field))
3988 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (field))))
3990 fieldsize = array_size_for_constructor (val);
3991 /* Given a non-empty initialization, this field had
3992 better be last. */
3993 if (fieldsize != 0 && TREE_CHAIN (field) != NULL_TREE)
3994 abort ();
3996 else if (DECL_SIZE_UNIT (field))
3998 /* ??? This can't be right. If the decl size overflows
3999 a host integer we will silently emit no data. */
4000 if (host_integerp (DECL_SIZE_UNIT (field), 1))
4001 fieldsize = tree_low_cst (DECL_SIZE_UNIT (field), 1);
4004 else
4005 fieldsize = int_size_in_bytes (TREE_TYPE (type));
4007 /* Output the element's initial value. */
4008 if (val == 0)
4009 assemble_zeros (fieldsize);
4010 else
4011 output_constant (val, fieldsize, align2);
4013 /* Count its size. */
4014 total_bytes += fieldsize;
4016 else if (val != 0 && TREE_CODE (val) != INTEGER_CST)
4017 error ("invalid initial value for member %qs",
4018 IDENTIFIER_POINTER (DECL_NAME (field)));
4019 else
4021 /* Element that is a bit-field. */
4023 HOST_WIDE_INT next_offset = int_bit_position (field);
4024 HOST_WIDE_INT end_offset
4025 = (next_offset + tree_low_cst (DECL_SIZE (field), 1));
4027 if (val == 0)
4028 val = integer_zero_node;
4030 /* If this field does not start in this (or, next) byte,
4031 skip some bytes. */
4032 if (next_offset / BITS_PER_UNIT != total_bytes)
4034 /* Output remnant of any bit field in previous bytes. */
4035 if (byte_buffer_in_use)
4037 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4038 total_bytes++;
4039 byte_buffer_in_use = 0;
4042 /* If still not at proper byte, advance to there. */
4043 if (next_offset / BITS_PER_UNIT != total_bytes)
4045 assemble_zeros (next_offset / BITS_PER_UNIT - total_bytes);
4046 total_bytes = next_offset / BITS_PER_UNIT;
4050 if (! byte_buffer_in_use)
4051 byte = 0;
4053 /* We must split the element into pieces that fall within
4054 separate bytes, and combine each byte with previous or
4055 following bit-fields. */
4057 /* next_offset is the offset n fbits from the beginning of
4058 the structure to the next bit of this element to be processed.
4059 end_offset is the offset of the first bit past the end of
4060 this element. */
4061 while (next_offset < end_offset)
4063 int this_time;
4064 int shift;
4065 HOST_WIDE_INT value;
4066 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
4067 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
4069 /* Advance from byte to byte
4070 within this element when necessary. */
4071 while (next_byte != total_bytes)
4073 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4074 total_bytes++;
4075 byte = 0;
4078 /* Number of bits we can process at once
4079 (all part of the same byte). */
4080 this_time = MIN (end_offset - next_offset,
4081 BITS_PER_UNIT - next_bit);
4082 if (BYTES_BIG_ENDIAN)
4084 /* On big-endian machine, take the most significant bits
4085 first (of the bits that are significant)
4086 and put them into bytes from the most significant end. */
4087 shift = end_offset - next_offset - this_time;
4089 /* Don't try to take a bunch of bits that cross
4090 the word boundary in the INTEGER_CST. We can
4091 only select bits from the LOW or HIGH part
4092 not from both. */
4093 if (shift < HOST_BITS_PER_WIDE_INT
4094 && shift + this_time > HOST_BITS_PER_WIDE_INT)
4096 this_time = shift + this_time - HOST_BITS_PER_WIDE_INT;
4097 shift = HOST_BITS_PER_WIDE_INT;
4100 /* Now get the bits from the appropriate constant word. */
4101 if (shift < HOST_BITS_PER_WIDE_INT)
4102 value = TREE_INT_CST_LOW (val);
4103 else if (shift < 2 * HOST_BITS_PER_WIDE_INT)
4105 value = TREE_INT_CST_HIGH (val);
4106 shift -= HOST_BITS_PER_WIDE_INT;
4108 else
4109 abort ();
4111 /* Get the result. This works only when:
4112 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
4113 byte |= (((value >> shift)
4114 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
4115 << (BITS_PER_UNIT - this_time - next_bit));
4117 else
4119 /* On little-endian machines,
4120 take first the least significant bits of the value
4121 and pack them starting at the least significant
4122 bits of the bytes. */
4123 shift = next_offset - int_bit_position (field);
4125 /* Don't try to take a bunch of bits that cross
4126 the word boundary in the INTEGER_CST. We can
4127 only select bits from the LOW or HIGH part
4128 not from both. */
4129 if (shift < HOST_BITS_PER_WIDE_INT
4130 && shift + this_time > HOST_BITS_PER_WIDE_INT)
4131 this_time = (HOST_BITS_PER_WIDE_INT - shift);
4133 /* Now get the bits from the appropriate constant word. */
4134 if (shift < HOST_BITS_PER_WIDE_INT)
4135 value = TREE_INT_CST_LOW (val);
4136 else if (shift < 2 * HOST_BITS_PER_WIDE_INT)
4138 value = TREE_INT_CST_HIGH (val);
4139 shift -= HOST_BITS_PER_WIDE_INT;
4141 else
4142 abort ();
4144 /* Get the result. This works only when:
4145 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
4146 byte |= (((value >> shift)
4147 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
4148 << next_bit);
4151 next_offset += this_time;
4152 byte_buffer_in_use = 1;
4157 if (byte_buffer_in_use)
4159 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4160 total_bytes++;
4163 if ((unsigned HOST_WIDE_INT)total_bytes < size)
4164 assemble_zeros (size - total_bytes);
4167 /* This TREE_LIST contains any weak symbol declarations waiting
4168 to be emitted. */
4169 static GTY(()) tree weak_decls;
4171 /* Mark DECL as weak. */
4173 static void
4174 mark_weak (tree decl)
4176 DECL_WEAK (decl) = 1;
4178 if (DECL_RTL_SET_P (decl)
4179 && MEM_P (DECL_RTL (decl))
4180 && XEXP (DECL_RTL (decl), 0)
4181 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
4182 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
4185 /* Merge weak status between NEWDECL and OLDDECL. */
4187 void
4188 merge_weak (tree newdecl, tree olddecl)
4190 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
4191 return;
4193 if (DECL_WEAK (newdecl))
4195 tree wd;
4197 /* NEWDECL is weak, but OLDDECL is not. */
4199 /* If we already output the OLDDECL, we're in trouble; we can't
4200 go back and make it weak. This error cannot caught in
4201 declare_weak because the NEWDECL and OLDDECL was not yet
4202 been merged; therefore, TREE_ASM_WRITTEN was not set. */
4203 if (TREE_ASM_WRITTEN (olddecl))
4204 error ("%Jweak declaration of %qD must precede definition",
4205 newdecl, newdecl);
4207 /* If we've already generated rtl referencing OLDDECL, we may
4208 have done so in a way that will not function properly with
4209 a weak symbol. */
4210 else if (TREE_USED (olddecl)
4211 && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)))
4212 warning ("%Jweak declaration of %qD after first use results "
4213 "in unspecified behavior", newdecl, newdecl);
4215 if (SUPPORTS_WEAK)
4217 /* We put the NEWDECL on the weak_decls list at some point.
4218 Replace it with the OLDDECL. */
4219 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
4220 if (TREE_VALUE (wd) == newdecl)
4222 TREE_VALUE (wd) = olddecl;
4223 break;
4225 /* We may not find the entry on the list. If NEWDECL is a
4226 weak alias, then we will have already called
4227 globalize_decl to remove the entry; in that case, we do
4228 not need to do anything. */
4231 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
4232 mark_weak (olddecl);
4234 else
4235 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
4236 weak. Just update NEWDECL to indicate that it's weak too. */
4237 mark_weak (newdecl);
4240 /* Declare DECL to be a weak symbol. */
4242 void
4243 declare_weak (tree decl)
4245 if (! TREE_PUBLIC (decl))
4246 error ("%Jweak declaration of %qD must be public", decl, decl);
4247 else if (TREE_CODE (decl) == FUNCTION_DECL && TREE_ASM_WRITTEN (decl))
4248 error ("%Jweak declaration of %qD must precede definition", decl, decl);
4249 else if (SUPPORTS_WEAK)
4251 if (! DECL_WEAK (decl))
4252 weak_decls = tree_cons (NULL, decl, weak_decls);
4254 else
4255 warning ("%Jweak declaration of %qD not supported", decl, decl);
4257 mark_weak (decl);
4260 /* Emit any pending weak declarations. */
4262 void
4263 weak_finish (void)
4265 tree t;
4267 for (t = weak_decls; t; t = TREE_CHAIN (t))
4269 tree decl = TREE_VALUE (t);
4270 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
4271 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
4272 #endif
4274 if (! TREE_USED (decl))
4275 continue;
4277 #ifdef ASM_WEAKEN_DECL
4278 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
4279 #else
4280 #ifdef ASM_WEAKEN_LABEL
4281 ASM_WEAKEN_LABEL (asm_out_file, name);
4282 #else
4283 #ifdef ASM_OUTPUT_WEAK_ALIAS
4284 warning ("only weak aliases are supported in this configuration");
4285 return;
4286 #endif
4287 #endif
4288 #endif
4292 /* Emit the assembly bits to indicate that DECL is globally visible. */
4294 static void
4295 globalize_decl (tree decl)
4297 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
4299 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
4300 if (DECL_WEAK (decl))
4302 tree *p, t;
4304 #ifdef ASM_WEAKEN_DECL
4305 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
4306 #else
4307 ASM_WEAKEN_LABEL (asm_out_file, name);
4308 #endif
4310 /* Remove this function from the pending weak list so that
4311 we do not emit multiple .weak directives for it. */
4312 for (p = &weak_decls; (t = *p) ; )
4314 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
4315 *p = TREE_CHAIN (t);
4316 else
4317 p = &TREE_CHAIN (t);
4319 return;
4321 #elif defined(ASM_MAKE_LABEL_LINKONCE)
4322 if (DECL_ONE_ONLY (decl))
4323 ASM_MAKE_LABEL_LINKONCE (asm_out_file, name);
4324 #endif
4326 targetm.asm_out.globalize_label (asm_out_file, name);
4329 /* Emit an assembler directive to make the symbol for DECL an alias to
4330 the symbol for TARGET. */
4332 void
4333 assemble_alias (tree decl, tree target ATTRIBUTE_UNUSED)
4335 const char *name;
4337 /* We must force creation of DECL_RTL for debug info generation, even though
4338 we don't use it here. */
4339 make_decl_rtl (decl);
4341 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
4343 #ifdef ASM_OUTPUT_DEF
4344 /* Make name accessible from other files, if appropriate. */
4346 if (TREE_PUBLIC (decl))
4348 globalize_decl (decl);
4349 maybe_assemble_visibility (decl);
4352 #ifdef ASM_OUTPUT_DEF_FROM_DECLS
4353 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
4354 #else
4355 ASM_OUTPUT_DEF (asm_out_file, name, IDENTIFIER_POINTER (target));
4356 #endif
4357 #else /* !ASM_OUTPUT_DEF */
4358 #if defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
4359 if (DECL_WEAK (decl))
4361 tree *p, t;
4362 #ifdef ASM_WEAKEN_DECL
4363 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
4364 #else
4365 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
4366 #endif
4367 /* Remove this function from the pending weak list so that
4368 we do not emit multiple .weak directives for it. */
4369 for (p = &weak_decls; (t = *p) ; )
4370 if (DECL_ASSEMBLER_NAME (decl)
4371 == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
4372 *p = TREE_CHAIN (t);
4373 else
4374 p = &TREE_CHAIN (t);
4376 else
4377 warning ("only weak aliases are supported in this configuration");
4379 #else
4380 warning ("alias definitions not supported in this configuration; ignored");
4381 #endif
4382 #endif
4384 TREE_USED (decl) = 1;
4385 TREE_ASM_WRITTEN (decl) = 1;
4386 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
4389 /* Emit an assembler directive to set symbol for DECL visibility to
4390 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
4392 void
4393 default_assemble_visibility (tree decl, int vis)
4395 static const char * const visibility_types[] = {
4396 NULL, "internal", "hidden", "protected"
4399 const char *name, *type;
4401 name = (IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)));
4402 type = visibility_types[vis];
4404 #ifdef HAVE_GAS_HIDDEN
4405 fprintf (asm_out_file, "\t.%s\t", type);
4406 assemble_name (asm_out_file, name);
4407 fprintf (asm_out_file, "\n");
4408 #else
4409 warning ("visibility attribute not supported in this configuration; ignored");
4410 #endif
4413 /* A helper function to call assemble_visibility when needed for a decl. */
4415 static void
4416 maybe_assemble_visibility (tree decl)
4418 enum symbol_visibility vis = DECL_VISIBILITY (decl);
4420 if (vis != VISIBILITY_DEFAULT)
4421 targetm.asm_out.visibility (decl, vis);
4424 /* Returns 1 if the target configuration supports defining public symbols
4425 so that one of them will be chosen at link time instead of generating a
4426 multiply-defined symbol error, whether through the use of weak symbols or
4427 a target-specific mechanism for having duplicates discarded. */
4430 supports_one_only (void)
4432 if (SUPPORTS_ONE_ONLY)
4433 return 1;
4434 return SUPPORTS_WEAK;
4437 /* Set up DECL as a public symbol that can be defined in multiple
4438 translation units without generating a linker error. */
4440 void
4441 make_decl_one_only (tree decl)
4443 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != FUNCTION_DECL)
4444 abort ();
4446 TREE_PUBLIC (decl) = 1;
4448 if (SUPPORTS_ONE_ONLY)
4450 #ifdef MAKE_DECL_ONE_ONLY
4451 MAKE_DECL_ONE_ONLY (decl);
4452 #endif
4453 DECL_ONE_ONLY (decl) = 1;
4455 else if (TREE_CODE (decl) == VAR_DECL
4456 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node))
4457 DECL_COMMON (decl) = 1;
4458 else if (SUPPORTS_WEAK)
4459 DECL_WEAK (decl) = 1;
4460 else
4461 abort ();
4464 void
4465 init_varasm_once (void)
4467 in_named_htab = htab_create_ggc (31, in_named_entry_hash,
4468 in_named_entry_eq, NULL);
4469 const_desc_htab = htab_create_ggc (1009, const_desc_hash,
4470 const_desc_eq, NULL);
4472 const_alias_set = new_alias_set ();
4475 enum tls_model
4476 decl_tls_model (tree decl)
4478 enum tls_model kind;
4479 tree attr = lookup_attribute ("tls_model", DECL_ATTRIBUTES (decl));
4480 bool is_local;
4482 if (attr)
4484 attr = TREE_VALUE (TREE_VALUE (attr));
4485 if (TREE_CODE (attr) != STRING_CST)
4486 abort ();
4487 if (!strcmp (TREE_STRING_POINTER (attr), "local-exec"))
4488 kind = TLS_MODEL_LOCAL_EXEC;
4489 else if (!strcmp (TREE_STRING_POINTER (attr), "initial-exec"))
4490 kind = TLS_MODEL_INITIAL_EXEC;
4491 else if (!strcmp (TREE_STRING_POINTER (attr), "local-dynamic"))
4492 kind = optimize ? TLS_MODEL_LOCAL_DYNAMIC : TLS_MODEL_GLOBAL_DYNAMIC;
4493 else if (!strcmp (TREE_STRING_POINTER (attr), "global-dynamic"))
4494 kind = TLS_MODEL_GLOBAL_DYNAMIC;
4495 else
4496 abort ();
4497 return kind;
4500 is_local = targetm.binds_local_p (decl);
4501 if (!flag_pic)
4503 if (is_local)
4504 kind = TLS_MODEL_LOCAL_EXEC;
4505 else
4506 kind = TLS_MODEL_INITIAL_EXEC;
4508 /* Local dynamic is inefficient when we're not combining the
4509 parts of the address. */
4510 else if (optimize && is_local)
4511 kind = TLS_MODEL_LOCAL_DYNAMIC;
4512 else
4513 kind = TLS_MODEL_GLOBAL_DYNAMIC;
4514 if (kind < flag_tls_default)
4515 kind = flag_tls_default;
4517 return kind;
4520 /* Select a set of attributes for section NAME based on the properties
4521 of DECL and whether or not RELOC indicates that DECL's initializer
4522 might contain runtime relocations.
4524 We make the section read-only and executable for a function decl,
4525 read-only for a const data decl, and writable for a non-const data decl. */
4527 unsigned int
4528 default_section_type_flags (tree decl, const char *name, int reloc)
4530 return default_section_type_flags_1 (decl, name, reloc, flag_pic);
4533 unsigned int
4534 default_section_type_flags_1 (tree decl, const char *name, int reloc,
4535 int shlib)
4537 unsigned int flags;
4539 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
4540 flags = SECTION_CODE;
4541 else if (decl && decl_readonly_section_1 (decl, reloc, shlib))
4542 flags = 0;
4543 else if (unlikely_text_section_name
4544 && strcmp (name, unlikely_text_section_name) == 0)
4545 flags = SECTION_CODE;
4546 else
4547 flags = SECTION_WRITE;
4549 if (decl && DECL_ONE_ONLY (decl))
4550 flags |= SECTION_LINKONCE;
4552 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl))
4553 flags |= SECTION_TLS | SECTION_WRITE;
4555 if (strcmp (name, ".bss") == 0
4556 || strncmp (name, ".bss.", 5) == 0
4557 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
4558 || strcmp (name, ".sbss") == 0
4559 || strncmp (name, ".sbss.", 6) == 0
4560 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0
4561 || strcmp (name, ".tbss") == 0
4562 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
4563 flags |= SECTION_BSS;
4565 if (strcmp (name, ".tdata") == 0
4566 || strcmp (name, ".tbss") == 0
4567 || strncmp (name, ".gnu.linkonce.td.", 17) == 0
4568 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
4569 flags |= SECTION_TLS;
4571 /* These three sections have special ELF types. They are neither
4572 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
4573 want to print a section type (@progbits or @nobits). If someone
4574 is silly enough to emit code or TLS variables to one of these
4575 sections, then don't handle them specially. */
4576 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
4577 && (strcmp (name, ".init_array") == 0
4578 || strcmp (name, ".fini_array") == 0
4579 || strcmp (name, ".preinit_array") == 0))
4580 flags |= SECTION_NOTYPE;
4582 return flags;
4585 /* Output assembly to switch to section NAME with attribute FLAGS.
4586 Four variants for common object file formats. */
4588 void
4589 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
4590 unsigned int flags ATTRIBUTE_UNUSED,
4591 tree decl ATTRIBUTE_UNUSED)
4593 /* Some object formats don't support named sections at all. The
4594 front-end should already have flagged this as an error. */
4595 abort ();
4598 void
4599 default_elf_asm_named_section (const char *name, unsigned int flags,
4600 tree decl ATTRIBUTE_UNUSED)
4602 char flagchars[10], *f = flagchars;
4604 /* If we have already declared this section, we can use an
4605 abbreviated form to switch back to it -- unless this section is
4606 part of a COMDAT groups, in which case GAS requires the full
4607 declaration every time. */
4608 if (!(HAVE_GAS_COMDAT_GROUP && (flags & SECTION_LINKONCE))
4609 && ! named_section_first_declaration (name))
4611 fprintf (asm_out_file, "\t.section\t%s\n", name);
4612 return;
4615 if (!(flags & SECTION_DEBUG))
4616 *f++ = 'a';
4617 if (flags & SECTION_WRITE)
4618 *f++ = 'w';
4619 if (flags & SECTION_CODE)
4620 *f++ = 'x';
4621 if (flags & SECTION_SMALL)
4622 *f++ = 's';
4623 if (flags & SECTION_MERGE)
4624 *f++ = 'M';
4625 if (flags & SECTION_STRINGS)
4626 *f++ = 'S';
4627 if (flags & SECTION_TLS)
4628 *f++ = 'T';
4629 if (HAVE_GAS_COMDAT_GROUP && (flags & SECTION_LINKONCE))
4630 *f++ = 'G';
4631 *f = '\0';
4633 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
4635 if (!(flags & SECTION_NOTYPE))
4637 const char *type;
4638 const char *format;
4640 if (flags & SECTION_BSS)
4641 type = "nobits";
4642 else
4643 type = "progbits";
4645 format = ",@%s";
4646 #ifdef ASM_COMMENT_START
4647 /* On platforms that use "@" as the assembly comment character,
4648 use "%" instead. */
4649 if (strcmp (ASM_COMMENT_START, "@") == 0)
4650 format = ",%%%s";
4651 #endif
4652 fprintf (asm_out_file, format, type);
4654 if (flags & SECTION_ENTSIZE)
4655 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
4656 if (HAVE_GAS_COMDAT_GROUP && (flags & SECTION_LINKONCE))
4657 fprintf (asm_out_file, ",%s,comdat",
4658 lang_hooks.decls.comdat_group (decl));
4661 putc ('\n', asm_out_file);
4664 void
4665 default_coff_asm_named_section (const char *name, unsigned int flags,
4666 tree decl ATTRIBUTE_UNUSED)
4668 char flagchars[8], *f = flagchars;
4670 if (flags & SECTION_WRITE)
4671 *f++ = 'w';
4672 if (flags & SECTION_CODE)
4673 *f++ = 'x';
4674 *f = '\0';
4676 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
4679 void
4680 default_pe_asm_named_section (const char *name, unsigned int flags,
4681 tree decl)
4683 default_coff_asm_named_section (name, flags, decl);
4685 if (flags & SECTION_LINKONCE)
4687 /* Functions may have been compiled at various levels of
4688 optimization so we can't use `same_size' here.
4689 Instead, have the linker pick one. */
4690 fprintf (asm_out_file, "\t.linkonce %s\n",
4691 (flags & SECTION_CODE ? "discard" : "same_size"));
4695 /* The lame default section selector. */
4697 void
4698 default_select_section (tree decl, int reloc,
4699 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
4701 bool readonly = false;
4703 if (DECL_P (decl))
4705 if (decl_readonly_section (decl, reloc))
4706 readonly = true;
4708 else if (TREE_CODE (decl) == CONSTRUCTOR)
4710 if (! ((flag_pic && reloc)
4711 || !TREE_READONLY (decl)
4712 || TREE_SIDE_EFFECTS (decl)
4713 || !TREE_CONSTANT (decl)))
4714 readonly = true;
4716 else if (TREE_CODE (decl) == STRING_CST)
4717 readonly = true;
4718 else if (! (flag_pic && reloc))
4719 readonly = true;
4721 if (readonly)
4722 readonly_data_section ();
4723 else
4724 data_section ();
4727 /* A helper function for default_elf_select_section and
4728 default_elf_unique_section. Categorizes the DECL. */
4730 enum section_category
4732 SECCAT_TEXT,
4734 SECCAT_RODATA,
4735 SECCAT_RODATA_MERGE_STR,
4736 SECCAT_RODATA_MERGE_STR_INIT,
4737 SECCAT_RODATA_MERGE_CONST,
4738 SECCAT_SRODATA,
4740 SECCAT_DATA,
4742 /* To optimize loading of shared programs, define following subsections
4743 of data section:
4744 _REL Contains data that has relocations, so they get grouped
4745 together and dynamic linker will visit fewer pages in memory.
4746 _RO Contains data that is otherwise read-only. This is useful
4747 with prelinking as most relocations won't be dynamically
4748 linked and thus stay read only.
4749 _LOCAL Marks data containing relocations only to local objects.
4750 These relocations will get fully resolved by prelinking. */
4751 SECCAT_DATA_REL,
4752 SECCAT_DATA_REL_LOCAL,
4753 SECCAT_DATA_REL_RO,
4754 SECCAT_DATA_REL_RO_LOCAL,
4756 SECCAT_SDATA,
4757 SECCAT_TDATA,
4759 SECCAT_BSS,
4760 SECCAT_SBSS,
4761 SECCAT_TBSS
4764 static enum section_category
4765 categorize_decl_for_section (tree, int, int);
4767 static enum section_category
4768 categorize_decl_for_section (tree decl, int reloc, int shlib)
4770 enum section_category ret;
4772 if (TREE_CODE (decl) == FUNCTION_DECL)
4773 return SECCAT_TEXT;
4774 else if (TREE_CODE (decl) == STRING_CST)
4776 if (flag_mudflap) /* or !flag_merge_constants */
4777 return SECCAT_RODATA;
4778 else
4779 return SECCAT_RODATA_MERGE_STR;
4781 else if (TREE_CODE (decl) == VAR_DECL)
4783 if (DECL_INITIAL (decl) == NULL
4784 || DECL_INITIAL (decl) == error_mark_node
4785 || (flag_zero_initialized_in_bss
4786 /* Leave constant zeroes in .rodata so they can be shared. */
4787 && !TREE_READONLY (decl)
4788 && initializer_zerop (DECL_INITIAL (decl))))
4789 ret = SECCAT_BSS;
4790 else if (! TREE_READONLY (decl)
4791 || TREE_SIDE_EFFECTS (decl)
4792 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
4794 if (shlib && (reloc & 2))
4795 ret = SECCAT_DATA_REL;
4796 else if (shlib && reloc)
4797 ret = SECCAT_DATA_REL_LOCAL;
4798 else
4799 ret = SECCAT_DATA;
4801 else if (shlib && (reloc & 2))
4802 ret = SECCAT_DATA_REL_RO;
4803 else if (shlib && reloc)
4804 ret = SECCAT_DATA_REL_RO_LOCAL;
4805 else if (reloc || flag_merge_constants < 2)
4806 /* C and C++ don't allow different variables to share the same
4807 location. -fmerge-all-constants allows even that (at the
4808 expense of not conforming). */
4809 ret = SECCAT_RODATA;
4810 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
4811 ret = SECCAT_RODATA_MERGE_STR_INIT;
4812 else
4813 ret = SECCAT_RODATA_MERGE_CONST;
4815 else if (TREE_CODE (decl) == CONSTRUCTOR)
4817 if ((shlib && reloc)
4818 || TREE_SIDE_EFFECTS (decl)
4819 || ! TREE_CONSTANT (decl))
4820 ret = SECCAT_DATA;
4821 else
4822 ret = SECCAT_RODATA;
4824 else
4825 ret = SECCAT_RODATA;
4827 /* There are no read-only thread-local sections. */
4828 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl))
4830 /* Note that this would be *just* SECCAT_BSS, except that there's
4831 no concept of a read-only thread-local-data section. */
4832 if (ret == SECCAT_BSS
4833 || (flag_zero_initialized_in_bss
4834 && initializer_zerop (DECL_INITIAL (decl))))
4835 ret = SECCAT_TBSS;
4836 else
4837 ret = SECCAT_TDATA;
4840 /* If the target uses small data sections, select it. */
4841 else if (targetm.in_small_data_p (decl))
4843 if (ret == SECCAT_BSS)
4844 ret = SECCAT_SBSS;
4845 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
4846 ret = SECCAT_SRODATA;
4847 else
4848 ret = SECCAT_SDATA;
4851 return ret;
4854 bool
4855 decl_readonly_section (tree decl, int reloc)
4857 return decl_readonly_section_1 (decl, reloc, flag_pic);
4860 bool
4861 decl_readonly_section_1 (tree decl, int reloc, int shlib)
4863 switch (categorize_decl_for_section (decl, reloc, shlib))
4865 case SECCAT_RODATA:
4866 case SECCAT_RODATA_MERGE_STR:
4867 case SECCAT_RODATA_MERGE_STR_INIT:
4868 case SECCAT_RODATA_MERGE_CONST:
4869 case SECCAT_SRODATA:
4870 return true;
4871 break;
4872 default:
4873 return false;
4874 break;
4878 /* Select a section based on the above categorization. */
4880 void
4881 default_elf_select_section (tree decl, int reloc,
4882 unsigned HOST_WIDE_INT align)
4884 default_elf_select_section_1 (decl, reloc, align, flag_pic);
4887 void
4888 default_elf_select_section_1 (tree decl, int reloc,
4889 unsigned HOST_WIDE_INT align, int shlib)
4891 switch (categorize_decl_for_section (decl, reloc, shlib))
4893 case SECCAT_TEXT:
4894 /* We're not supposed to be called on FUNCTION_DECLs. */
4895 abort ();
4896 case SECCAT_RODATA:
4897 readonly_data_section ();
4898 break;
4899 case SECCAT_RODATA_MERGE_STR:
4900 mergeable_string_section (decl, align, 0);
4901 break;
4902 case SECCAT_RODATA_MERGE_STR_INIT:
4903 mergeable_string_section (DECL_INITIAL (decl), align, 0);
4904 break;
4905 case SECCAT_RODATA_MERGE_CONST:
4906 mergeable_constant_section (DECL_MODE (decl), align, 0);
4907 break;
4908 case SECCAT_SRODATA:
4909 named_section (NULL_TREE, ".sdata2", reloc);
4910 break;
4911 case SECCAT_DATA:
4912 data_section ();
4913 break;
4914 case SECCAT_DATA_REL:
4915 named_section (NULL_TREE, ".data.rel", reloc);
4916 break;
4917 case SECCAT_DATA_REL_LOCAL:
4918 named_section (NULL_TREE, ".data.rel.local", reloc);
4919 break;
4920 case SECCAT_DATA_REL_RO:
4921 named_section (NULL_TREE, ".data.rel.ro", reloc);
4922 break;
4923 case SECCAT_DATA_REL_RO_LOCAL:
4924 named_section (NULL_TREE, ".data.rel.ro.local", reloc);
4925 break;
4926 case SECCAT_SDATA:
4927 named_section (NULL_TREE, ".sdata", reloc);
4928 break;
4929 case SECCAT_TDATA:
4930 named_section (NULL_TREE, ".tdata", reloc);
4931 break;
4932 case SECCAT_BSS:
4933 #ifdef BSS_SECTION_ASM_OP
4934 bss_section ();
4935 #else
4936 named_section (NULL_TREE, ".bss", reloc);
4937 #endif
4938 break;
4939 case SECCAT_SBSS:
4940 named_section (NULL_TREE, ".sbss", reloc);
4941 break;
4942 case SECCAT_TBSS:
4943 named_section (NULL_TREE, ".tbss", reloc);
4944 break;
4945 default:
4946 abort ();
4950 /* Construct a unique section name based on the decl name and the
4951 categorization performed above. */
4953 void
4954 default_unique_section (tree decl, int reloc)
4956 default_unique_section_1 (decl, reloc, flag_pic);
4959 void
4960 default_unique_section_1 (tree decl, int reloc, int shlib)
4962 bool one_only = DECL_ONE_ONLY (decl);
4963 const char *prefix, *name;
4964 size_t nlen, plen;
4965 char *string;
4967 switch (categorize_decl_for_section (decl, reloc, shlib))
4969 case SECCAT_TEXT:
4970 prefix = one_only ? ".gnu.linkonce.t." : ".text.";
4971 break;
4972 case SECCAT_RODATA:
4973 case SECCAT_RODATA_MERGE_STR:
4974 case SECCAT_RODATA_MERGE_STR_INIT:
4975 case SECCAT_RODATA_MERGE_CONST:
4976 prefix = one_only ? ".gnu.linkonce.r." : ".rodata.";
4977 break;
4978 case SECCAT_SRODATA:
4979 prefix = one_only ? ".gnu.linkonce.s2." : ".sdata2.";
4980 break;
4981 case SECCAT_DATA:
4982 case SECCAT_DATA_REL:
4983 case SECCAT_DATA_REL_LOCAL:
4984 case SECCAT_DATA_REL_RO:
4985 case SECCAT_DATA_REL_RO_LOCAL:
4986 prefix = one_only ? ".gnu.linkonce.d." : ".data.";
4987 break;
4988 case SECCAT_SDATA:
4989 prefix = one_only ? ".gnu.linkonce.s." : ".sdata.";
4990 break;
4991 case SECCAT_BSS:
4992 prefix = one_only ? ".gnu.linkonce.b." : ".bss.";
4993 break;
4994 case SECCAT_SBSS:
4995 prefix = one_only ? ".gnu.linkonce.sb." : ".sbss.";
4996 break;
4997 case SECCAT_TDATA:
4998 prefix = one_only ? ".gnu.linkonce.td." : ".tdata.";
4999 break;
5000 case SECCAT_TBSS:
5001 prefix = one_only ? ".gnu.linkonce.tb." : ".tbss.";
5002 break;
5003 default:
5004 abort ();
5006 plen = strlen (prefix);
5008 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5009 name = targetm.strip_name_encoding (name);
5010 nlen = strlen (name);
5012 string = alloca (nlen + plen + 1);
5013 memcpy (string, prefix, plen);
5014 memcpy (string + plen, name, nlen + 1);
5016 DECL_SECTION_NAME (decl) = build_string (nlen + plen, string);
5019 void
5020 default_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
5021 rtx x,
5022 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
5024 if (flag_pic)
5025 switch (GET_CODE (x))
5027 case CONST:
5028 case SYMBOL_REF:
5029 case LABEL_REF:
5030 data_section ();
5031 return;
5033 default:
5034 break;
5037 readonly_data_section ();
5040 void
5041 default_elf_select_rtx_section (enum machine_mode mode, rtx x,
5042 unsigned HOST_WIDE_INT align)
5044 /* ??? Handle small data here somehow. */
5046 if (flag_pic)
5047 switch (GET_CODE (x))
5049 case CONST:
5050 case SYMBOL_REF:
5051 named_section (NULL_TREE, ".data.rel.ro", 3);
5052 return;
5054 case LABEL_REF:
5055 named_section (NULL_TREE, ".data.rel.ro.local", 1);
5056 return;
5058 default:
5059 break;
5062 mergeable_constant_section (mode, align, 0);
5065 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
5067 void
5068 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
5070 rtx symbol;
5071 int flags;
5073 /* Careful not to prod global register variables. */
5074 if (!MEM_P (rtl))
5075 return;
5076 symbol = XEXP (rtl, 0);
5077 if (GET_CODE (symbol) != SYMBOL_REF)
5078 return;
5080 flags = 0;
5081 if (TREE_CODE (decl) == FUNCTION_DECL)
5082 flags |= SYMBOL_FLAG_FUNCTION;
5083 if (targetm.binds_local_p (decl))
5084 flags |= SYMBOL_FLAG_LOCAL;
5085 if (targetm.in_small_data_p (decl))
5086 flags |= SYMBOL_FLAG_SMALL;
5087 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl))
5088 flags |= decl_tls_model (decl) << SYMBOL_FLAG_TLS_SHIFT;
5089 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
5090 being PUBLIC, the thing *must* be defined in this translation unit.
5091 Prevent this buglet from being propagated into rtl code as well. */
5092 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
5093 flags |= SYMBOL_FLAG_EXTERNAL;
5095 SYMBOL_REF_FLAGS (symbol) = flags;
5098 /* By default, we do nothing for encode_section_info, so we need not
5099 do anything but discard the '*' marker. */
5101 const char *
5102 default_strip_name_encoding (const char *str)
5104 return str + (*str == '*');
5107 /* Assume ELF-ish defaults, since that's pretty much the most liberal
5108 wrt cross-module name binding. */
5110 bool
5111 default_binds_local_p (tree exp)
5113 return default_binds_local_p_1 (exp, flag_shlib);
5116 bool
5117 default_binds_local_p_1 (tree exp, int shlib)
5119 bool local_p;
5121 /* A non-decl is an entry in the constant pool. */
5122 if (!DECL_P (exp))
5123 local_p = true;
5124 /* Static variables are always local. */
5125 else if (! TREE_PUBLIC (exp))
5126 local_p = true;
5127 /* A variable is local if the user explicitly tells us so. */
5128 else if (DECL_VISIBILITY_SPECIFIED (exp) && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
5129 local_p = true;
5130 /* Otherwise, variables defined outside this object may not be local. */
5131 else if (DECL_EXTERNAL (exp))
5132 local_p = false;
5133 /* Linkonce and weak data are never local. */
5134 else if (DECL_ONE_ONLY (exp) || DECL_WEAK (exp))
5135 local_p = false;
5136 /* If none of the above and visibility is not default, make local. */
5137 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
5138 local_p = true;
5139 /* If PIC, then assume that any global name can be overridden by
5140 symbols resolved from other modules. */
5141 else if (shlib)
5142 local_p = false;
5143 /* Uninitialized COMMON variable may be unified with symbols
5144 resolved from other modules. */
5145 else if (DECL_COMMON (exp)
5146 && (DECL_INITIAL (exp) == NULL
5147 || DECL_INITIAL (exp) == error_mark_node))
5148 local_p = false;
5149 /* Otherwise we're left with initialized (or non-common) global data
5150 which is of necessity defined locally. */
5151 else
5152 local_p = true;
5154 return local_p;
5157 /* Determine whether or not a pointer mode is valid. Assume defaults
5158 of ptr_mode or Pmode - can be overridden. */
5159 bool
5160 default_valid_pointer_mode (enum machine_mode mode)
5162 return (mode == ptr_mode || mode == Pmode);
5165 /* Default function to output code that will globalize a label. A
5166 target must define GLOBAL_ASM_OP or provide it's own function to
5167 globalize a label. */
5168 #ifdef GLOBAL_ASM_OP
5169 void
5170 default_globalize_label (FILE * stream, const char *name)
5172 fputs (GLOBAL_ASM_OP, stream);
5173 assemble_name (stream, name);
5174 putc ('\n', stream);
5176 #endif /* GLOBAL_ASM_OP */
5178 /* Default function to output a label for unwind information. The
5179 default is to do nothing. A target that needs nonlocal labels for
5180 unwind information must provide its own function to do this. */
5181 void
5182 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
5183 tree decl ATTRIBUTE_UNUSED,
5184 int for_eh ATTRIBUTE_UNUSED,
5185 int empty ATTRIBUTE_UNUSED)
5189 /* This is how to output an internal numbered label where PREFIX is
5190 the class of label and LABELNO is the number within the class. */
5192 void
5193 default_internal_label (FILE *stream, const char *prefix,
5194 unsigned long labelno)
5196 char *const buf = alloca (40 + strlen (prefix));
5197 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
5198 ASM_OUTPUT_LABEL (stream, buf);
5201 /* This is the default behavior at the beginning of a file. It's
5202 controlled by two other target-hook toggles. */
5203 void
5204 default_file_start (void)
5206 if (targetm.file_start_app_off && !flag_verbose_asm)
5207 fputs (ASM_APP_OFF, asm_out_file);
5209 if (targetm.file_start_file_directive)
5210 output_file_directive (asm_out_file, main_input_filename);
5213 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
5214 which emits a special section directive used to indicate whether or
5215 not this object file needs an executable stack. This is primarily
5216 a GNU extension to ELF but could be used on other targets. */
5218 int trampolines_created;
5220 void
5221 file_end_indicate_exec_stack (void)
5223 unsigned int flags = SECTION_DEBUG;
5224 if (trampolines_created)
5225 flags |= SECTION_CODE;
5227 named_section_flags (".note.GNU-stack", flags);
5230 #include "gt-varasm.h"