PR target/17735
[official-gcc.git] / gcc / varasm.c
blobaaf9e53b22ce5a65400c15f72d66a3ab50621b0b
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 /* The (assembler) name of the first globally-visible object output. */
61 const char *first_global_object_name;
62 const char *weak_global_object_name;
64 struct addr_const;
65 struct constant_descriptor_rtx;
66 struct rtx_constant_pool;
68 struct varasm_status GTY(())
70 /* If we're using a per-function constant pool, this is it. */
71 struct rtx_constant_pool *pool;
73 /* Number of tree-constants deferred during the expansion of this
74 function. */
75 unsigned int deferred_constants;
78 #define n_deferred_constants (cfun->varasm->deferred_constants)
80 /* Number for making the label on the next
81 constant that is stored in memory. */
83 static GTY(()) int const_labelno;
85 /* Carry information from ASM_DECLARE_OBJECT_NAME
86 to ASM_FINISH_DECLARE_OBJECT. */
88 int size_directive_output;
90 /* The last decl for which assemble_variable was called,
91 if it did ASM_DECLARE_OBJECT_NAME.
92 If the last call to assemble_variable didn't do that,
93 this holds 0. */
95 tree last_assemble_variable_decl;
97 /* The following global variable indicates if the section label for the
98 "cold" section of code has been output yet to the assembler. The
99 label is useful when running gdb. This is part of the optimization that
100 partitions hot and cold basic blocks into separate sections of the .o
101 file. */
103 static bool unlikely_section_label_printed = false;
105 /* The following global variable indicates the label name to be put at
106 the start of the first cold section within each function, when
107 partitioning basic blocks into hot and cold sections. */
109 static char *unlikely_section_label = NULL;
111 /* The following global variable indicates the section name to be used
112 for the current cold section, when partitioning hot and cold basic
113 blocks into separate sections. */
115 static char *unlikely_text_section_name = NULL;
117 /* We give all constants their own alias set. Perhaps redundant with
118 MEM_READONLY_P, but pre-dates it. */
120 static HOST_WIDE_INT const_alias_set;
122 static const char *strip_reg_name (const char *);
123 static int contains_pointers_p (tree);
124 #ifdef ASM_OUTPUT_EXTERNAL
125 static bool incorporeal_function_p (tree);
126 #endif
127 static void decode_addr_const (tree, struct addr_const *);
128 static hashval_t const_desc_hash (const void *);
129 static int const_desc_eq (const void *, const void *);
130 static hashval_t const_hash_1 (const tree);
131 static int compare_constant (const tree, const tree);
132 static tree copy_constant (tree);
133 static void output_constant_def_contents (rtx);
134 static void output_addressed_constants (tree);
135 static unsigned HOST_WIDE_INT array_size_for_constructor (tree);
136 static unsigned min_align (unsigned, unsigned);
137 static void output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int);
138 static void globalize_decl (tree);
139 static void maybe_assemble_visibility (tree);
140 static int in_named_entry_eq (const void *, const void *);
141 static hashval_t in_named_entry_hash (const void *);
142 #ifdef BSS_SECTION_ASM_OP
143 #ifdef ASM_OUTPUT_BSS
144 static void asm_output_bss (FILE *, tree, const char *,
145 unsigned HOST_WIDE_INT, unsigned HOST_WIDE_INT);
146 #endif
147 #ifdef ASM_OUTPUT_ALIGNED_BSS
148 static void asm_output_aligned_bss (FILE *, tree, const char *,
149 unsigned HOST_WIDE_INT, int)
150 ATTRIBUTE_UNUSED;
151 #endif
152 #endif /* BSS_SECTION_ASM_OP */
153 static bool asm_emit_uninitialised (tree, const char*,
154 unsigned HOST_WIDE_INT,
155 unsigned HOST_WIDE_INT);
156 static void mark_weak (tree);
158 enum in_section { no_section, in_text, in_unlikely_executed_text, in_data,
159 in_named
160 #ifdef BSS_SECTION_ASM_OP
161 , in_bss
162 #endif
163 #ifdef CTORS_SECTION_ASM_OP
164 , in_ctors
165 #endif
166 #ifdef DTORS_SECTION_ASM_OP
167 , in_dtors
168 #endif
169 #ifdef READONLY_DATA_SECTION_ASM_OP
170 , in_readonly_data
171 #endif
172 #ifdef EXTRA_SECTIONS
173 , EXTRA_SECTIONS
174 #endif
176 static GTY(()) enum in_section in_section = no_section;
178 /* Return a nonzero value if DECL has a section attribute. */
179 #ifndef IN_NAMED_SECTION
180 #define IN_NAMED_SECTION(DECL) \
181 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \
182 && DECL_SECTION_NAME (DECL) != NULL_TREE)
183 #endif
185 /* Text of section name when in_section == in_named. */
186 static GTY(()) const char *in_named_name;
188 /* Hash table of flags that have been used for a particular named section. */
190 struct in_named_entry GTY(())
192 const char *name;
193 unsigned int flags;
194 bool declared;
197 static GTY((param_is (struct in_named_entry))) htab_t in_named_htab;
199 /* Define functions like text_section for any extra sections. */
200 #ifdef EXTRA_SECTION_FUNCTIONS
201 EXTRA_SECTION_FUNCTIONS
202 #endif
204 /* Tell assembler to switch to text section. */
206 void
207 text_section (void)
209 if (in_section != in_text)
211 in_section = in_text;
212 fprintf (asm_out_file, "%s\n", TEXT_SECTION_ASM_OP);
216 /* Tell assembler to switch to unlikely-to-be-executed text section. */
218 void
219 unlikely_text_section (void)
221 const char *name;
222 int len;
224 if (! unlikely_text_section_name)
226 if (DECL_SECTION_NAME (current_function_decl)
227 && (strcmp (TREE_STRING_POINTER (DECL_SECTION_NAME
228 (current_function_decl)),
229 HOT_TEXT_SECTION_NAME) != 0)
230 && (strcmp (TREE_STRING_POINTER (DECL_SECTION_NAME
231 (current_function_decl)),
232 UNLIKELY_EXECUTED_TEXT_SECTION_NAME) != 0))
234 name = TREE_STRING_POINTER (DECL_SECTION_NAME
235 (current_function_decl));
236 len = strlen (name);
237 unlikely_text_section_name = xmalloc ((len + 10) * sizeof (char));
238 strcpy (unlikely_text_section_name, name);
239 strcat (unlikely_text_section_name, "_unlikely");
241 else
243 len = strlen (UNLIKELY_EXECUTED_TEXT_SECTION_NAME);
244 unlikely_text_section_name = xmalloc (len+1 * sizeof (char));
245 strcpy (unlikely_text_section_name,
246 UNLIKELY_EXECUTED_TEXT_SECTION_NAME);
250 if ((in_section != in_unlikely_executed_text)
251 && (in_section != in_named
252 || strcmp (in_named_name, unlikely_text_section_name) != 0))
254 named_section (NULL_TREE, unlikely_text_section_name, 0);
255 in_section = in_unlikely_executed_text;
257 if (!unlikely_section_label_printed)
259 ASM_OUTPUT_LABEL (asm_out_file, unlikely_section_label);
260 unlikely_section_label_printed = true;
265 /* Tell assembler to switch to data section. */
267 void
268 data_section (void)
270 if (in_section != in_data)
272 in_section = in_data;
273 fprintf (asm_out_file, "%s\n", DATA_SECTION_ASM_OP);
277 /* Tell assembler to switch to read-only data section. This is normally
278 the text section. */
280 void
281 readonly_data_section (void)
283 #ifdef READONLY_DATA_SECTION
284 READONLY_DATA_SECTION (); /* Note this can call data_section. */
285 #else
286 #ifdef READONLY_DATA_SECTION_ASM_OP
287 if (in_section != in_readonly_data)
289 in_section = in_readonly_data;
290 fputs (READONLY_DATA_SECTION_ASM_OP, asm_out_file);
291 fputc ('\n', asm_out_file);
293 #else
294 text_section ();
295 #endif
296 #endif
299 /* Determine if we're in the text section. */
302 in_text_section (void)
304 return in_section == in_text;
307 /* Determine if we're in the unlikely-to-be-executed text section. */
310 in_unlikely_text_section (void)
312 bool ret_val;
314 ret_val = ((in_section == in_unlikely_executed_text)
315 || (in_section == in_named
316 && unlikely_text_section_name
317 && strcmp (in_named_name, unlikely_text_section_name) == 0));
319 return ret_val;
322 /* Determine if we're in the data section. */
325 in_data_section (void)
327 return in_section == in_data;
330 /* Helper routines for maintaining in_named_htab. */
332 static int
333 in_named_entry_eq (const void *p1, const void *p2)
335 const struct in_named_entry *old = p1;
336 const char *new = p2;
338 return strcmp (old->name, new) == 0;
341 static hashval_t
342 in_named_entry_hash (const void *p)
344 const struct in_named_entry *old = p;
345 return htab_hash_string (old->name);
348 /* If SECTION has been seen before as a named section, return the flags
349 that were used. Otherwise, return 0. Note, that 0 is a perfectly valid
350 set of flags for a section to have, so 0 does not mean that the section
351 has not been seen. */
353 static unsigned int
354 get_named_section_flags (const char *section)
356 struct in_named_entry **slot;
358 slot = (struct in_named_entry **)
359 htab_find_slot_with_hash (in_named_htab, section,
360 htab_hash_string (section), NO_INSERT);
362 return slot ? (*slot)->flags : 0;
365 /* Returns true if the section has been declared before. Sets internal
366 flag on this section in in_named_hash so subsequent calls on this
367 section will return false. */
369 bool
370 named_section_first_declaration (const char *name)
372 struct in_named_entry **slot;
374 slot = (struct in_named_entry **)
375 htab_find_slot_with_hash (in_named_htab, name,
376 htab_hash_string (name), NO_INSERT);
377 if (! (*slot)->declared)
379 (*slot)->declared = true;
380 return true;
382 else
384 return false;
389 /* Record FLAGS for SECTION. If SECTION was previously recorded with a
390 different set of flags, return false. */
392 bool
393 set_named_section_flags (const char *section, unsigned int flags)
395 struct in_named_entry **slot, *entry;
397 slot = (struct in_named_entry **)
398 htab_find_slot_with_hash (in_named_htab, section,
399 htab_hash_string (section), INSERT);
400 entry = *slot;
402 if (!entry)
404 entry = ggc_alloc (sizeof (*entry));
405 *slot = entry;
406 entry->name = ggc_strdup (section);
407 entry->flags = flags;
408 entry->declared = false;
410 else if (entry->flags != flags)
411 return false;
413 return true;
416 /* Tell assembler to change to section NAME with attributes FLAGS. If
417 DECL is non-NULL, it is the VAR_DECL or FUNCTION_DECL with which
418 this section is associated. */
420 void
421 named_section_real (const char *name, unsigned int flags, tree decl)
423 if (in_section != in_named || strcmp (name, in_named_name) != 0)
425 if (! set_named_section_flags (name, flags))
426 abort ();
428 targetm.asm_out.named_section (name, flags, decl);
430 if (flags & SECTION_FORGET)
431 in_section = no_section;
432 else
434 in_named_name = ggc_strdup (name);
435 in_section = in_named;
440 /* Tell assembler to change to section NAME for DECL.
441 If DECL is NULL, just switch to section NAME.
442 If NAME is NULL, get the name from DECL.
443 If RELOC is 1, the initializer for DECL contains relocs. */
445 void
446 named_section (tree decl, const char *name, int reloc)
448 unsigned int flags;
450 if (decl != NULL_TREE && !DECL_P (decl))
451 abort ();
452 if (name == NULL)
453 name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
455 if (strcmp (name, UNLIKELY_EXECUTED_TEXT_SECTION_NAME) == 0
456 && !unlikely_text_section_name)
458 unlikely_text_section_name = xmalloc
459 (strlen (UNLIKELY_EXECUTED_TEXT_SECTION_NAME) + 1
460 * sizeof (char));
461 strcpy (unlikely_text_section_name,
462 UNLIKELY_EXECUTED_TEXT_SECTION_NAME);
465 flags = targetm.section_type_flags (decl, name, reloc);
467 /* Sanity check user variables for flag changes. Non-user
468 section flag changes will abort in named_section_flags.
469 However, don't complain if SECTION_OVERRIDE is set.
470 We trust that the setter knows that it is safe to ignore
471 the default flags for this decl. */
472 if (decl && ! set_named_section_flags (name, flags))
474 flags = get_named_section_flags (name);
475 if ((flags & SECTION_OVERRIDE) == 0)
476 error ("%J%D causes a section type conflict", decl, decl);
479 named_section_real (name, flags, decl);
482 /* If required, set DECL_SECTION_NAME to a unique name. */
484 void
485 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
486 int flag_function_or_data_sections)
488 if (DECL_SECTION_NAME (decl) == NULL_TREE
489 && targetm.have_named_sections
490 && (flag_function_or_data_sections
491 || DECL_ONE_ONLY (decl)))
492 targetm.asm_out.unique_section (decl, reloc);
495 #ifdef BSS_SECTION_ASM_OP
497 /* Tell the assembler to switch to the bss section. */
499 void
500 bss_section (void)
502 if (in_section != in_bss)
504 fprintf (asm_out_file, "%s\n", BSS_SECTION_ASM_OP);
505 in_section = in_bss;
509 #ifdef ASM_OUTPUT_BSS
511 /* Utility function for ASM_OUTPUT_BSS for targets to use if
512 they don't support alignments in .bss.
513 ??? It is believed that this function will work in most cases so such
514 support is localized here. */
516 static void
517 asm_output_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
518 const char *name,
519 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
520 unsigned HOST_WIDE_INT rounded)
522 targetm.asm_out.globalize_label (file, name);
523 bss_section ();
524 #ifdef ASM_DECLARE_OBJECT_NAME
525 last_assemble_variable_decl = decl;
526 ASM_DECLARE_OBJECT_NAME (file, name, decl);
527 #else
528 /* Standard thing is just output label for the object. */
529 ASM_OUTPUT_LABEL (file, name);
530 #endif /* ASM_DECLARE_OBJECT_NAME */
531 ASM_OUTPUT_SKIP (file, rounded ? rounded : 1);
534 #endif
536 #ifdef ASM_OUTPUT_ALIGNED_BSS
538 /* Utility function for targets to use in implementing
539 ASM_OUTPUT_ALIGNED_BSS.
540 ??? It is believed that this function will work in most cases so such
541 support is localized here. */
543 static void
544 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
545 const char *name, unsigned HOST_WIDE_INT size,
546 int align)
548 bss_section ();
549 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
550 #ifdef ASM_DECLARE_OBJECT_NAME
551 last_assemble_variable_decl = decl;
552 ASM_DECLARE_OBJECT_NAME (file, name, decl);
553 #else
554 /* Standard thing is just output label for the object. */
555 ASM_OUTPUT_LABEL (file, name);
556 #endif /* ASM_DECLARE_OBJECT_NAME */
557 ASM_OUTPUT_SKIP (file, size ? size : 1);
560 #endif
562 #endif /* BSS_SECTION_ASM_OP */
564 /* Switch to the section for function DECL.
566 If DECL is NULL_TREE, switch to the text section. We can be passed
567 NULL_TREE under some circumstances by dbxout.c at least. */
569 void
570 function_section (tree decl)
572 if (decl == NULL_TREE)
573 text_section ();
574 else
576 /* ??? Typical use of this function maybe shouldn't be looking
577 for unlikely blocks at all - in the event that an entire
578 function is going into the unlikely-execute section, that
579 should be reflected in its DECL_SECTION_NAME. */
580 rtx insns = cfun && cfun->emit ? get_insns () : 0;
581 bool unlikely = insns && scan_ahead_for_unlikely_executed_note (insns);
583 #ifdef USE_SELECT_SECTION_FOR_FUNCTIONS
584 targetm.asm_out.select_section (decl, unlikely, DECL_ALIGN (decl));
585 #else
586 if (unlikely)
587 unlikely_text_section ();
588 else if (DECL_SECTION_NAME (decl))
589 named_section (decl, 0, 0);
590 else
591 text_section ();
592 #endif
596 /* Switch to read-only data section associated with function DECL. */
598 void
599 default_function_rodata_section (tree decl)
601 if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
603 const char *name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
605 /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo. */
606 if (DECL_ONE_ONLY (decl) && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
608 size_t len = strlen (name) + 1;
609 char *rname = alloca (len);
611 memcpy (rname, name, len);
612 rname[14] = 'r';
613 named_section_real (rname, SECTION_LINKONCE, decl);
614 return;
616 /* For .text.foo we want to use .rodata.foo. */
617 else if (flag_function_sections && flag_data_sections
618 && strncmp (name, ".text.", 6) == 0)
620 size_t len = strlen (name) + 1;
621 char *rname = alloca (len + 2);
623 memcpy (rname, ".rodata", 7);
624 memcpy (rname + 7, name + 5, len - 5);
625 named_section_flags (rname, 0);
626 return;
630 readonly_data_section ();
633 /* Switch to read-only data section associated with function DECL
634 for targets where that section should be always the single
635 readonly data section. */
637 void
638 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
640 readonly_data_section ();
643 /* Switch to section for variable DECL. RELOC is the same as the
644 argument to SELECT_SECTION. */
646 void
647 variable_section (tree decl, int reloc)
649 if (IN_NAMED_SECTION (decl))
650 named_section (decl, NULL, reloc);
651 else
652 targetm.asm_out.select_section (decl, reloc, DECL_ALIGN (decl));
655 /* Tell assembler to switch to the section for string merging. */
657 void
658 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
659 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
660 unsigned int flags ATTRIBUTE_UNUSED)
662 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
663 && TREE_CODE (decl) == STRING_CST
664 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
665 && align <= 256
666 && TREE_STRING_LENGTH (decl) >= int_size_in_bytes (TREE_TYPE (decl)))
668 enum machine_mode mode;
669 unsigned int modesize;
670 const char *str;
671 int i, j, len, unit;
672 char name[30];
674 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
675 modesize = GET_MODE_BITSIZE (mode);
676 if (modesize >= 8 && modesize <= 256
677 && (modesize & (modesize - 1)) == 0)
679 if (align < modesize)
680 align = modesize;
682 str = TREE_STRING_POINTER (decl);
683 len = TREE_STRING_LENGTH (decl);
684 unit = GET_MODE_SIZE (mode);
686 /* Check for embedded NUL characters. */
687 for (i = 0; i < len; i += unit)
689 for (j = 0; j < unit; j++)
690 if (str[i + j] != '\0')
691 break;
692 if (j == unit)
693 break;
695 if (i == len - unit)
697 sprintf (name, ".rodata.str%d.%d", modesize / 8,
698 (int) (align / 8));
699 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
700 if (!i && modesize < align)
702 /* A "" string with requested alignment greater than
703 character size might cause a problem:
704 if some other string required even bigger
705 alignment than "", then linker might think the
706 "" is just part of padding after some other string
707 and not put it into the hash table initially.
708 But this means "" could have smaller alignment
709 than requested. */
710 #ifdef ASM_OUTPUT_SECTION_START
711 named_section_flags (name, flags);
712 ASM_OUTPUT_SECTION_START (asm_out_file);
713 #else
714 readonly_data_section ();
715 #endif
716 return;
719 named_section_flags (name, flags);
720 return;
725 readonly_data_section ();
728 /* Tell assembler to switch to the section for constant merging. */
730 void
731 mergeable_constant_section (enum machine_mode mode ATTRIBUTE_UNUSED,
732 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
733 unsigned int flags ATTRIBUTE_UNUSED)
735 unsigned int modesize = GET_MODE_BITSIZE (mode);
737 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
738 && mode != VOIDmode
739 && mode != BLKmode
740 && modesize <= align
741 && align >= 8
742 && align <= 256
743 && (align & (align - 1)) == 0)
745 char name[24];
747 sprintf (name, ".rodata.cst%d", (int) (align / 8));
748 flags |= (align / 8) | SECTION_MERGE;
749 named_section_flags (name, flags);
750 return;
753 readonly_data_section ();
756 /* Given NAME, a putative register name, discard any customary prefixes. */
758 static const char *
759 strip_reg_name (const char *name)
761 #ifdef REGISTER_PREFIX
762 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
763 name += strlen (REGISTER_PREFIX);
764 #endif
765 if (name[0] == '%' || name[0] == '#')
766 name++;
767 return name;
770 /* The user has asked for a DECL to have a particular name. Set (or
771 change) it in such a way that we don't prefix an underscore to
772 it. */
773 void
774 set_user_assembler_name (tree decl, const char *name)
776 char *starred = alloca (strlen (name) + 2);
777 starred[0] = '*';
778 strcpy (starred + 1, name);
779 change_decl_assembler_name (decl, get_identifier (starred));
780 SET_DECL_RTL (decl, NULL_RTX);
783 /* Decode an `asm' spec for a declaration as a register name.
784 Return the register number, or -1 if nothing specified,
785 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
786 or -3 if ASMSPEC is `cc' and is not recognized,
787 or -4 if ASMSPEC is `memory' and is not recognized.
788 Accept an exact spelling or a decimal number.
789 Prefixes such as % are optional. */
792 decode_reg_name (const char *asmspec)
794 if (asmspec != 0 && strlen (asmspec) != 0)
796 int i;
798 /* Get rid of confusing prefixes. */
799 asmspec = strip_reg_name (asmspec);
801 /* Allow a decimal number as a "register name". */
802 for (i = strlen (asmspec) - 1; i >= 0; i--)
803 if (! ISDIGIT (asmspec[i]))
804 break;
805 if (asmspec[0] != 0 && i < 0)
807 i = atoi (asmspec);
808 if (i < FIRST_PSEUDO_REGISTER && i >= 0)
809 return i;
810 else
811 return -2;
814 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
815 if (reg_names[i][0]
816 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
817 return i;
819 #ifdef ADDITIONAL_REGISTER_NAMES
821 static const struct { const char *const name; const int number; } table[]
822 = ADDITIONAL_REGISTER_NAMES;
824 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
825 if (! strcmp (asmspec, table[i].name))
826 return table[i].number;
828 #endif /* ADDITIONAL_REGISTER_NAMES */
830 if (!strcmp (asmspec, "memory"))
831 return -4;
833 if (!strcmp (asmspec, "cc"))
834 return -3;
836 return -2;
839 return -1;
842 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
843 have static storage duration. In other words, it should not be an
844 automatic variable, including PARM_DECLs.
846 There is, however, one exception: this function handles variables
847 explicitly placed in a particular register by the user.
849 This is never called for PARM_DECL nodes. */
851 void
852 make_decl_rtl (tree decl)
854 const char *name = 0;
855 int reg_number;
856 rtx x;
858 /* Check that we are not being given an automatic variable. */
859 /* A weak alias has TREE_PUBLIC set but not the other bits. */
860 if (TREE_CODE (decl) == PARM_DECL
861 || TREE_CODE (decl) == RESULT_DECL
862 || (TREE_CODE (decl) == VAR_DECL
863 && !TREE_STATIC (decl)
864 && !TREE_PUBLIC (decl)
865 && !DECL_EXTERNAL (decl)
866 && !DECL_REGISTER (decl)))
867 abort ();
868 /* And that we were not given a type or a label. */
869 else if (TREE_CODE (decl) == TYPE_DECL
870 || TREE_CODE (decl) == LABEL_DECL)
871 abort ();
873 /* For a duplicate declaration, we can be called twice on the
874 same DECL node. Don't discard the RTL already made. */
875 if (DECL_RTL_SET_P (decl))
877 /* If the old RTL had the wrong mode, fix the mode. */
878 if (GET_MODE (DECL_RTL (decl)) != DECL_MODE (decl))
879 SET_DECL_RTL (decl, adjust_address_nv (DECL_RTL (decl),
880 DECL_MODE (decl), 0));
882 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
883 return;
885 /* ??? Another way to do this would be to maintain a hashed
886 table of such critters. Instead of adding stuff to a DECL
887 to give certain attributes to it, we could use an external
888 hash map from DECL to set of attributes. */
890 /* Let the target reassign the RTL if it wants.
891 This is necessary, for example, when one machine specific
892 decl attribute overrides another. */
893 targetm.encode_section_info (decl, DECL_RTL (decl), false);
895 /* Make this function static known to the mudflap runtime. */
896 if (flag_mudflap && TREE_CODE (decl) == VAR_DECL)
897 mudflap_enqueue_decl (decl);
899 return;
902 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
904 reg_number = decode_reg_name (name);
906 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
908 /* First detect errors in declaring global registers. */
909 if (reg_number == -1)
910 error ("%Jregister name not specified for %qD", decl, decl);
911 else if (reg_number < 0)
912 error ("%Jinvalid register name for %qD", decl, decl);
913 else if (TYPE_MODE (TREE_TYPE (decl)) == BLKmode)
914 error ("%Jdata type of %qD isn%'t suitable for a register",
915 decl, decl);
916 else if (! HARD_REGNO_MODE_OK (reg_number, TYPE_MODE (TREE_TYPE (decl))))
917 error ("%Jregister specified for %qD isn%'t suitable for data type",
918 decl, decl);
919 /* Now handle properly declared static register variables. */
920 else
922 int nregs;
924 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
926 DECL_INITIAL (decl) = 0;
927 error ("global register variable has initial value");
929 if (TREE_THIS_VOLATILE (decl))
930 warning ("volatile register variables don%'t "
931 "work as you might wish");
933 /* If the user specified one of the eliminables registers here,
934 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
935 confused with that register and be eliminated. This usage is
936 somewhat suspect... */
938 SET_DECL_RTL (decl, gen_rtx_raw_REG (DECL_MODE (decl), reg_number));
939 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
940 REG_USERVAR_P (DECL_RTL (decl)) = 1;
942 if (TREE_STATIC (decl))
944 /* Make this register global, so not usable for anything
945 else. */
946 #ifdef ASM_DECLARE_REGISTER_GLOBAL
947 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
948 #endif
949 nregs = hard_regno_nregs[reg_number][DECL_MODE (decl)];
950 while (nregs > 0)
951 globalize_reg (reg_number + --nregs);
954 /* As a register variable, it has no section. */
955 return;
959 /* Now handle ordinary static variables and functions (in memory).
960 Also handle vars declared register invalidly. */
962 if (name[0] == '*' && (reg_number >= 0 || reg_number == -3))
963 error ("%Jregister name given for non-register variable %qD", decl, decl);
965 /* Specifying a section attribute on a variable forces it into a
966 non-.bss section, and thus it cannot be common. */
967 if (TREE_CODE (decl) == VAR_DECL
968 && DECL_SECTION_NAME (decl) != NULL_TREE
969 && DECL_INITIAL (decl) == NULL_TREE
970 && DECL_COMMON (decl))
971 DECL_COMMON (decl) = 0;
973 /* Variables can't be both common and weak. */
974 if (TREE_CODE (decl) == VAR_DECL && DECL_WEAK (decl))
975 DECL_COMMON (decl) = 0;
977 x = gen_rtx_SYMBOL_REF (Pmode, name);
978 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
979 SYMBOL_REF_DECL (x) = decl;
981 x = gen_rtx_MEM (DECL_MODE (decl), x);
982 if (TREE_CODE (decl) != FUNCTION_DECL)
983 set_mem_attributes (x, decl, 1);
984 SET_DECL_RTL (decl, x);
986 /* Optionally set flags or add text to the name to record information
987 such as that it is a function name.
988 If the name is changed, the macro ASM_OUTPUT_LABELREF
989 will have to know how to strip this information. */
990 targetm.encode_section_info (decl, DECL_RTL (decl), true);
992 /* Make this function static known to the mudflap runtime. */
993 if (flag_mudflap && TREE_CODE (decl) == VAR_DECL)
994 mudflap_enqueue_decl (decl);
997 /* Make the rtl for variable VAR be volatile.
998 Use this only for static variables. */
1000 void
1001 make_var_volatile (tree var)
1003 if (!MEM_P (DECL_RTL (var)))
1004 abort ();
1006 MEM_VOLATILE_P (DECL_RTL (var)) = 1;
1009 /* Output a string of literal assembler code
1010 for an `asm' keyword used between functions. */
1012 void
1013 assemble_asm (tree string)
1015 app_enable ();
1017 if (TREE_CODE (string) == ADDR_EXPR)
1018 string = TREE_OPERAND (string, 0);
1020 fprintf (asm_out_file, "\t%s\n", TREE_STRING_POINTER (string));
1023 /* Record an element in the table of global destructors. SYMBOL is
1024 a SYMBOL_REF of the function to be called; PRIORITY is a number
1025 between 0 and MAX_INIT_PRIORITY. */
1027 void
1028 default_stabs_asm_out_destructor (rtx symbol ATTRIBUTE_UNUSED,
1029 int priority ATTRIBUTE_UNUSED)
1031 #if defined DBX_DEBUGGING_INFO || defined XCOFF_DEBUGGING_INFO
1032 /* Tell GNU LD that this is part of the static destructor set.
1033 This will work for any system that uses stabs, most usefully
1034 aout systems. */
1035 dbxout_begin_simple_stabs ("___DTOR_LIST__", 22 /* N_SETT */);
1036 dbxout_stab_value_label (XSTR (symbol, 0));
1037 #else
1038 sorry ("global destructors not supported on this target");
1039 #endif
1042 void
1043 default_named_section_asm_out_destructor (rtx symbol, int priority)
1045 const char *section = ".dtors";
1046 char buf[16];
1048 /* ??? This only works reliably with the GNU linker. */
1049 if (priority != DEFAULT_INIT_PRIORITY)
1051 sprintf (buf, ".dtors.%.5u",
1052 /* Invert the numbering so the linker puts us in the proper
1053 order; constructors are run from right to left, and the
1054 linker sorts in increasing order. */
1055 MAX_INIT_PRIORITY - priority);
1056 section = buf;
1059 named_section_flags (section, SECTION_WRITE);
1060 assemble_align (POINTER_SIZE);
1061 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1064 #ifdef DTORS_SECTION_ASM_OP
1065 void
1066 dtors_section (void)
1068 if (in_section != in_dtors)
1070 in_section = in_dtors;
1071 fputs (DTORS_SECTION_ASM_OP, asm_out_file);
1072 fputc ('\n', asm_out_file);
1076 void
1077 default_dtor_section_asm_out_destructor (rtx symbol,
1078 int priority ATTRIBUTE_UNUSED)
1080 dtors_section ();
1081 assemble_align (POINTER_SIZE);
1082 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1084 #endif
1086 /* Likewise for global constructors. */
1088 void
1089 default_stabs_asm_out_constructor (rtx symbol ATTRIBUTE_UNUSED,
1090 int priority ATTRIBUTE_UNUSED)
1092 #if defined DBX_DEBUGGING_INFO || defined XCOFF_DEBUGGING_INFO
1093 /* Tell GNU LD that this is part of the static destructor set.
1094 This will work for any system that uses stabs, most usefully
1095 aout systems. */
1096 dbxout_begin_simple_stabs ("___CTOR_LIST__", 22 /* N_SETT */);
1097 dbxout_stab_value_label (XSTR (symbol, 0));
1098 #else
1099 sorry ("global constructors not supported on this target");
1100 #endif
1103 void
1104 default_named_section_asm_out_constructor (rtx symbol, int priority)
1106 const char *section = ".ctors";
1107 char buf[16];
1109 /* ??? This only works reliably with the GNU linker. */
1110 if (priority != DEFAULT_INIT_PRIORITY)
1112 sprintf (buf, ".ctors.%.5u",
1113 /* Invert the numbering so the linker puts us in the proper
1114 order; constructors are run from right to left, and the
1115 linker sorts in increasing order. */
1116 MAX_INIT_PRIORITY - priority);
1117 section = buf;
1120 named_section_flags (section, SECTION_WRITE);
1121 assemble_align (POINTER_SIZE);
1122 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1125 #ifdef CTORS_SECTION_ASM_OP
1126 void
1127 ctors_section (void)
1129 if (in_section != in_ctors)
1131 in_section = in_ctors;
1132 fputs (CTORS_SECTION_ASM_OP, asm_out_file);
1133 fputc ('\n', asm_out_file);
1137 void
1138 default_ctor_section_asm_out_constructor (rtx symbol,
1139 int priority ATTRIBUTE_UNUSED)
1141 ctors_section ();
1142 assemble_align (POINTER_SIZE);
1143 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1145 #endif
1147 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1148 a nonzero value if the constant pool should be output before the
1149 start of the function, or a zero value if the pool should output
1150 after the end of the function. The default is to put it before the
1151 start. */
1153 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1154 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1155 #endif
1157 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1158 to be output to assembler.
1159 Set first_global_object_name and weak_global_object_name as appropriate. */
1161 void
1162 notice_global_symbol (tree decl)
1164 const char **type = &first_global_object_name;
1166 if (first_global_object_name
1167 || !TREE_PUBLIC (decl) || DECL_EXTERNAL (decl)
1168 || !DECL_NAME (decl)
1169 || (TREE_CODE (decl) != FUNCTION_DECL
1170 && (TREE_CODE (decl) != VAR_DECL
1171 || (DECL_COMMON (decl)
1172 && (DECL_INITIAL (decl) == 0
1173 || DECL_INITIAL (decl) == error_mark_node))))
1174 || !MEM_P (DECL_RTL (decl)))
1175 return;
1177 /* We win when global object is found, but it is useful to know about weak
1178 symbol as well so we can produce nicer unique names. */
1179 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl))
1180 type = &weak_global_object_name;
1182 if (!*type)
1184 const char *p;
1185 char *name;
1186 rtx decl_rtl = DECL_RTL (decl);
1188 p = targetm.strip_name_encoding (XSTR (XEXP (decl_rtl, 0), 0));
1189 name = xstrdup (p);
1191 *type = name;
1195 /* Output assembler code for the constant pool of a function and associated
1196 with defining the name of the function. DECL describes the function.
1197 NAME is the function's name. For the constant pool, we use the current
1198 constant pool data. */
1200 void
1201 assemble_start_function (tree decl, const char *fnname)
1203 int align;
1205 if (unlikely_text_section_name)
1206 free (unlikely_text_section_name);
1208 unlikely_section_label_printed = false;
1209 unlikely_text_section_name = NULL;
1211 unlikely_section_label = reconcat (unlikely_section_label,
1212 fnname, ".unlikely_section", NULL);
1214 /* The following code does not need preprocessing in the assembler. */
1216 app_disable ();
1218 if (CONSTANT_POOL_BEFORE_FUNCTION)
1219 output_constant_pool (fnname, decl);
1221 /* Make sure the cold text (code) section is properly aligned. This
1222 is necessary here in the case where the function has both hot and
1223 cold sections, because we don't want to re-set the alignment when the
1224 section switch happens mid-function. We don't need to set the hot
1225 section alignment here, because code further down in this function
1226 sets the alignment for whichever section comes first, and if there
1227 is a hot section it is guaranteed to be first. */
1229 if (flag_reorder_blocks_and_partition)
1231 unlikely_text_section ();
1232 assemble_align (FUNCTION_BOUNDARY);
1235 resolve_unique_section (decl, 0, flag_function_sections);
1236 function_section (decl);
1238 /* Tell assembler to move to target machine's alignment for functions. */
1239 align = floor_log2 (FUNCTION_BOUNDARY / BITS_PER_UNIT);
1240 if (align < force_align_functions_log)
1241 align = force_align_functions_log;
1242 if (align > 0)
1244 ASM_OUTPUT_ALIGN (asm_out_file, align);
1247 /* Handle a user-specified function alignment.
1248 Note that we still need to align to FUNCTION_BOUNDARY, as above,
1249 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1250 if (align_functions_log > align
1251 && cfun->function_frequency != FUNCTION_FREQUENCY_UNLIKELY_EXECUTED)
1253 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1254 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1255 align_functions_log, align_functions - 1);
1256 #else
1257 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1258 #endif
1261 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1262 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1263 #endif
1265 (*debug_hooks->begin_function) (decl);
1267 /* Make function name accessible from other files, if appropriate. */
1269 if (TREE_PUBLIC (decl))
1271 notice_global_symbol (decl);
1273 globalize_decl (decl);
1275 maybe_assemble_visibility (decl);
1278 if (DECL_PRESERVE_P (decl))
1279 targetm.asm_out.mark_decl_preserved (fnname);
1281 /* Do any machine/system dependent processing of the function name. */
1282 #ifdef ASM_DECLARE_FUNCTION_NAME
1283 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1284 #else
1285 /* Standard thing is just output label for the function. */
1286 ASM_OUTPUT_LABEL (asm_out_file, fnname);
1287 #endif /* ASM_DECLARE_FUNCTION_NAME */
1289 if (in_unlikely_text_section ()
1290 && !unlikely_section_label_printed)
1292 ASM_OUTPUT_LABEL (asm_out_file, unlikely_section_label);
1293 unlikely_section_label_printed = true;
1297 /* Output assembler code associated with defining the size of the
1298 function. DECL describes the function. NAME is the function's name. */
1300 void
1301 assemble_end_function (tree decl, const char *fnname)
1303 #ifdef ASM_DECLARE_FUNCTION_SIZE
1304 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1305 #endif
1306 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1308 output_constant_pool (fnname, decl);
1309 function_section (decl); /* need to switch back */
1313 /* Assemble code to leave SIZE bytes of zeros. */
1315 void
1316 assemble_zeros (unsigned HOST_WIDE_INT size)
1318 /* Do no output if -fsyntax-only. */
1319 if (flag_syntax_only)
1320 return;
1322 #ifdef ASM_NO_SKIP_IN_TEXT
1323 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1324 so we must output 0s explicitly in the text section. */
1325 if ((ASM_NO_SKIP_IN_TEXT && in_text_section ())
1326 || (ASM_NO_SKIP_IN_TEXT && in_unlikely_text_section ()))
1328 unsigned HOST_WIDE_INT i;
1329 for (i = 0; i < size; i++)
1330 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1332 else
1333 #endif
1334 if (size > 0)
1335 ASM_OUTPUT_SKIP (asm_out_file, size);
1338 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1340 void
1341 assemble_align (int align)
1343 if (align > BITS_PER_UNIT)
1345 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1349 /* Assemble a string constant with the specified C string as contents. */
1351 void
1352 assemble_string (const char *p, int size)
1354 int pos = 0;
1355 int maximum = 2000;
1357 /* If the string is very long, split it up. */
1359 while (pos < size)
1361 int thissize = size - pos;
1362 if (thissize > maximum)
1363 thissize = maximum;
1365 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1367 pos += thissize;
1368 p += thissize;
1373 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1374 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1375 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1376 #else
1377 #if defined ASM_OUTPUT_ALIGNED_LOCAL
1378 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1379 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, DECL_ALIGN (decl))
1380 #else
1381 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1382 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded)
1383 #endif
1384 #endif
1386 #if defined ASM_OUTPUT_ALIGNED_BSS
1387 #define ASM_EMIT_BSS(decl, name, size, rounded) \
1388 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1389 #else
1390 #if defined ASM_OUTPUT_BSS
1391 #define ASM_EMIT_BSS(decl, name, size, rounded) \
1392 ASM_OUTPUT_BSS (asm_out_file, decl, name, size, rounded)
1393 #else
1394 #undef ASM_EMIT_BSS
1395 #endif
1396 #endif
1398 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1399 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1400 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1401 #else
1402 #if defined ASM_OUTPUT_ALIGNED_COMMON
1403 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1404 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size, DECL_ALIGN (decl))
1405 #else
1406 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1407 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded)
1408 #endif
1409 #endif
1411 static bool
1412 asm_emit_uninitialised (tree decl, const char *name,
1413 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1414 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1416 enum
1418 asm_dest_common,
1419 asm_dest_bss,
1420 asm_dest_local
1422 destination = asm_dest_local;
1424 /* ??? We should handle .bss via select_section mechanisms rather than
1425 via special target hooks. That would eliminate this special case. */
1426 if (TREE_PUBLIC (decl))
1428 if (!DECL_COMMON (decl))
1429 #ifdef ASM_EMIT_BSS
1430 destination = asm_dest_bss;
1431 #else
1432 return false;
1433 #endif
1434 else
1435 destination = asm_dest_common;
1438 if (destination == asm_dest_bss)
1439 globalize_decl (decl);
1440 resolve_unique_section (decl, 0, flag_data_sections);
1442 if (flag_shared_data)
1444 switch (destination)
1446 #ifdef ASM_OUTPUT_SHARED_BSS
1447 case asm_dest_bss:
1448 ASM_OUTPUT_SHARED_BSS (asm_out_file, decl, name, size, rounded);
1449 return;
1450 #endif
1451 #ifdef ASM_OUTPUT_SHARED_COMMON
1452 case asm_dest_common:
1453 ASM_OUTPUT_SHARED_COMMON (asm_out_file, name, size, rounded);
1454 return;
1455 #endif
1456 #ifdef ASM_OUTPUT_SHARED_LOCAL
1457 case asm_dest_local:
1458 ASM_OUTPUT_SHARED_LOCAL (asm_out_file, name, size, rounded);
1459 return;
1460 #endif
1461 default:
1462 break;
1466 switch (destination)
1468 #ifdef ASM_EMIT_BSS
1469 case asm_dest_bss:
1470 ASM_EMIT_BSS (decl, name, size, rounded);
1471 break;
1472 #endif
1473 case asm_dest_common:
1474 ASM_EMIT_COMMON (decl, name, size, rounded);
1475 break;
1476 case asm_dest_local:
1477 ASM_EMIT_LOCAL (decl, name, size, rounded);
1478 break;
1479 default:
1480 abort ();
1483 return true;
1486 /* Assemble everything that is needed for a variable or function declaration.
1487 Not used for automatic variables, and not used for function definitions.
1488 Should not be called for variables of incomplete structure type.
1490 TOP_LEVEL is nonzero if this variable has file scope.
1491 AT_END is nonzero if this is the special handling, at end of compilation,
1492 to define things that have had only tentative definitions.
1493 DONT_OUTPUT_DATA if nonzero means don't actually output the
1494 initial value (that will be done by the caller). */
1496 void
1497 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
1498 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
1500 const char *name;
1501 unsigned int align;
1502 int reloc = 0;
1503 rtx decl_rtl;
1505 if (lang_hooks.decls.prepare_assemble_variable)
1506 lang_hooks.decls.prepare_assemble_variable (decl);
1508 last_assemble_variable_decl = 0;
1510 /* Normally no need to say anything here for external references,
1511 since assemble_external is called by the language-specific code
1512 when a declaration is first seen. */
1514 if (DECL_EXTERNAL (decl))
1515 return;
1517 /* Output no assembler code for a function declaration.
1518 Only definitions of functions output anything. */
1520 if (TREE_CODE (decl) == FUNCTION_DECL)
1521 return;
1523 /* Do nothing for global register variables. */
1524 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
1526 TREE_ASM_WRITTEN (decl) = 1;
1527 return;
1530 /* If type was incomplete when the variable was declared,
1531 see if it is complete now. */
1533 if (DECL_SIZE (decl) == 0)
1534 layout_decl (decl, 0);
1536 /* Still incomplete => don't allocate it; treat the tentative defn
1537 (which is what it must have been) as an `extern' reference. */
1539 if (!dont_output_data && DECL_SIZE (decl) == 0)
1541 error ("%Jstorage size of %qD isn%'t known", decl, decl);
1542 TREE_ASM_WRITTEN (decl) = 1;
1543 return;
1546 /* The first declaration of a variable that comes through this function
1547 decides whether it is global (in C, has external linkage)
1548 or local (in C, has internal linkage). So do nothing more
1549 if this function has already run. */
1551 if (TREE_ASM_WRITTEN (decl))
1552 return;
1554 /* Make sure targetm.encode_section_info is invoked before we set
1555 ASM_WRITTEN. */
1556 decl_rtl = DECL_RTL (decl);
1558 TREE_ASM_WRITTEN (decl) = 1;
1560 /* Do no output if -fsyntax-only. */
1561 if (flag_syntax_only)
1562 return;
1564 app_disable ();
1566 if (! dont_output_data
1567 && ! host_integerp (DECL_SIZE_UNIT (decl), 1))
1569 error ("%Jsize of variable %qD is too large", decl, decl);
1570 return;
1573 name = XSTR (XEXP (decl_rtl, 0), 0);
1574 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
1575 notice_global_symbol (decl);
1577 /* Compute the alignment of this data. */
1579 align = DECL_ALIGN (decl);
1581 /* In the case for initialing an array whose length isn't specified,
1582 where we have not yet been able to do the layout,
1583 figure out the proper alignment now. */
1584 if (dont_output_data && DECL_SIZE (decl) == 0
1585 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
1586 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
1588 /* Some object file formats have a maximum alignment which they support.
1589 In particular, a.out format supports a maximum alignment of 4. */
1590 if (align > MAX_OFILE_ALIGNMENT)
1592 warning ("%Jalignment of %qD is greater than maximum object "
1593 "file alignment. Using %d", decl, decl,
1594 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
1595 align = MAX_OFILE_ALIGNMENT;
1598 /* On some machines, it is good to increase alignment sometimes. */
1599 if (! DECL_USER_ALIGN (decl))
1601 #ifdef DATA_ALIGNMENT
1602 align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1603 #endif
1604 #ifdef CONSTANT_ALIGNMENT
1605 if (DECL_INITIAL (decl) != 0 && DECL_INITIAL (decl) != error_mark_node)
1606 align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
1607 #endif
1610 /* Reset the alignment in case we have made it tighter, so we can benefit
1611 from it in get_pointer_alignment. */
1612 DECL_ALIGN (decl) = align;
1613 set_mem_align (decl_rtl, align);
1615 if (TREE_PUBLIC (decl))
1616 maybe_assemble_visibility (decl);
1618 if (DECL_PRESERVE_P (decl))
1619 targetm.asm_out.mark_decl_preserved (name);
1621 /* Output any data that we will need to use the address of. */
1622 if (DECL_INITIAL (decl) == error_mark_node)
1623 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1624 else if (DECL_INITIAL (decl))
1626 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1627 output_addressed_constants (DECL_INITIAL (decl));
1629 resolve_unique_section (decl, reloc, flag_data_sections);
1631 /* Handle uninitialized definitions. */
1633 /* If the decl has been given an explicit section name, then it
1634 isn't common, and shouldn't be handled as such. */
1635 if (DECL_SECTION_NAME (decl) || dont_output_data)
1637 /* We don't implement common thread-local data at present. */
1638 else if (DECL_THREAD_LOCAL (decl))
1640 if (DECL_COMMON (decl))
1641 sorry ("thread-local COMMON data not implemented");
1643 else if (DECL_INITIAL (decl) == 0
1644 || DECL_INITIAL (decl) == error_mark_node
1645 || (flag_zero_initialized_in_bss
1646 /* Leave constant zeroes in .rodata so they can be shared. */
1647 && !TREE_READONLY (decl)
1648 && initializer_zerop (DECL_INITIAL (decl))))
1650 unsigned HOST_WIDE_INT size = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
1651 unsigned HOST_WIDE_INT rounded = size;
1653 /* Don't allocate zero bytes of common,
1654 since that means "undefined external" in the linker. */
1655 if (size == 0)
1656 rounded = 1;
1658 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1659 so that each uninitialized object starts on such a boundary. */
1660 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
1661 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1662 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1664 #if !defined(ASM_OUTPUT_ALIGNED_COMMON) && !defined(ASM_OUTPUT_ALIGNED_DECL_COMMON) && !defined(ASM_OUTPUT_ALIGNED_BSS)
1665 if ((unsigned HOST_WIDE_INT) DECL_ALIGN_UNIT (decl) > rounded)
1666 warning ("%Jrequested alignment for %qD is greater than "
1667 "implemented alignment of %d", decl, decl, rounded);
1668 #endif
1670 /* If the target cannot output uninitialized but not common global data
1671 in .bss, then we have to use .data, so fall through. */
1672 if (asm_emit_uninitialised (decl, name, size, rounded))
1673 return;
1676 /* Handle initialized definitions.
1677 Also handle uninitialized global definitions if -fno-common and the
1678 target doesn't support ASM_OUTPUT_BSS. */
1680 /* First make the assembler name(s) global if appropriate. */
1681 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
1682 globalize_decl (decl);
1684 /* Switch to the appropriate section. */
1685 variable_section (decl, reloc);
1687 /* dbxout.c needs to know this. */
1688 if (in_text_section () || in_unlikely_text_section ())
1689 DECL_IN_TEXT_SECTION (decl) = 1;
1691 /* Output the alignment of this data. */
1692 if (align > BITS_PER_UNIT)
1693 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (DECL_ALIGN_UNIT (decl)));
1695 /* Do any machine/system dependent processing of the object. */
1696 #ifdef ASM_DECLARE_OBJECT_NAME
1697 last_assemble_variable_decl = decl;
1698 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
1699 #else
1700 /* Standard thing is just output label for the object. */
1701 ASM_OUTPUT_LABEL (asm_out_file, name);
1702 #endif /* ASM_DECLARE_OBJECT_NAME */
1704 if (!dont_output_data)
1706 if (DECL_INITIAL (decl)
1707 && DECL_INITIAL (decl) != error_mark_node
1708 && !initializer_zerop (DECL_INITIAL (decl)))
1709 /* Output the actual data. */
1710 output_constant (DECL_INITIAL (decl),
1711 tree_low_cst (DECL_SIZE_UNIT (decl), 1),
1712 align);
1713 else
1714 /* Leave space for it. */
1715 assemble_zeros (tree_low_cst (DECL_SIZE_UNIT (decl), 1));
1719 /* Return 1 if type TYPE contains any pointers. */
1721 static int
1722 contains_pointers_p (tree type)
1724 switch (TREE_CODE (type))
1726 case POINTER_TYPE:
1727 case REFERENCE_TYPE:
1728 /* I'm not sure whether OFFSET_TYPE needs this treatment,
1729 so I'll play safe and return 1. */
1730 case OFFSET_TYPE:
1731 return 1;
1733 case RECORD_TYPE:
1734 case UNION_TYPE:
1735 case QUAL_UNION_TYPE:
1737 tree fields;
1738 /* For a type that has fields, see if the fields have pointers. */
1739 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
1740 if (TREE_CODE (fields) == FIELD_DECL
1741 && contains_pointers_p (TREE_TYPE (fields)))
1742 return 1;
1743 return 0;
1746 case ARRAY_TYPE:
1747 /* An array type contains pointers if its element type does. */
1748 return contains_pointers_p (TREE_TYPE (type));
1750 default:
1751 return 0;
1755 #ifdef ASM_OUTPUT_EXTERNAL
1756 /* True if DECL is a function decl for which no out-of-line copy exists.
1757 It is assumed that DECL's assembler name has been set. */
1759 static bool
1760 incorporeal_function_p (tree decl)
1762 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
1764 const char *name;
1766 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
1767 && DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA)
1768 return true;
1770 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
1771 if (strncmp (name, "__builtin_", strlen ("__builtin_")) == 0)
1772 return true;
1774 return false;
1776 #endif
1778 /* Output something to declare an external symbol to the assembler.
1779 (Most assemblers don't need this, so we normally output nothing.)
1780 Do nothing if DECL is not external. */
1782 void
1783 assemble_external (tree decl ATTRIBUTE_UNUSED)
1785 /* Because most platforms do not define ASM_OUTPUT_EXTERNAL, the
1786 main body of this code is only rarely exercised. To provide some
1787 testing, on all platforms, we make sure that the ASM_OUT_FILE is
1788 open. If it's not, we should not be calling this function. */
1789 if (!asm_out_file)
1790 abort ();
1792 #ifdef ASM_OUTPUT_EXTERNAL
1793 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
1795 rtx rtl = DECL_RTL (decl);
1797 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
1798 && !SYMBOL_REF_USED (XEXP (rtl, 0))
1799 && !incorporeal_function_p (decl))
1801 /* Some systems do require some output. */
1802 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
1803 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
1806 #endif
1809 /* Similar, for calling a library function FUN. */
1811 void
1812 assemble_external_libcall (rtx fun)
1814 /* Declare library function name external when first used, if nec. */
1815 if (! SYMBOL_REF_USED (fun))
1817 SYMBOL_REF_USED (fun) = 1;
1818 targetm.asm_out.external_libcall (fun);
1822 /* Assemble a label named NAME. */
1824 void
1825 assemble_label (const char *name)
1827 ASM_OUTPUT_LABEL (asm_out_file, name);
1830 /* Set the symbol_referenced flag for ID. */
1831 void
1832 mark_referenced (tree id)
1834 TREE_SYMBOL_REFERENCED (id) = 1;
1837 /* Set the symbol_referenced flag for DECL and notify callgraph. */
1838 void
1839 mark_decl_referenced (tree decl)
1841 if (TREE_CODE (decl) == FUNCTION_DECL)
1842 cgraph_mark_needed_node (cgraph_node (decl));
1843 else if (TREE_CODE (decl) == VAR_DECL)
1844 cgraph_varpool_mark_needed_node (cgraph_varpool_node (decl));
1845 /* else do nothing - we can get various sorts of CST nodes here,
1846 which do not need to be marked. */
1849 /* Output to FILE a reference to the assembler name of a C-level name NAME.
1850 If NAME starts with a *, the rest of NAME is output verbatim.
1851 Otherwise NAME is transformed in an implementation-defined way
1852 (usually by the addition of an underscore).
1853 Many macros in the tm file are defined to call this function. */
1855 void
1856 assemble_name (FILE *file, const char *name)
1858 const char *real_name;
1859 tree id;
1861 real_name = targetm.strip_name_encoding (name);
1863 id = maybe_get_identifier (real_name);
1864 if (id)
1865 mark_referenced (id);
1867 if (name[0] == '*')
1868 fputs (&name[1], file);
1869 else
1870 ASM_OUTPUT_LABELREF (file, name);
1873 /* Allocate SIZE bytes writable static space with a gensym name
1874 and return an RTX to refer to its address. */
1877 assemble_static_space (unsigned HOST_WIDE_INT size)
1879 char name[12];
1880 const char *namestring;
1881 rtx x;
1883 #if 0
1884 if (flag_shared_data)
1885 data_section ();
1886 #endif
1888 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
1889 ++const_labelno;
1890 namestring = ggc_strdup (name);
1892 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
1893 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
1895 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
1896 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
1897 BIGGEST_ALIGNMENT);
1898 #else
1899 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
1900 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
1901 #else
1903 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1904 so that each uninitialized object starts on such a boundary. */
1905 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
1906 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
1907 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
1908 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1909 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1910 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1912 #endif
1913 #endif
1914 return x;
1917 /* Assemble the static constant template for function entry trampolines.
1918 This is done at most once per compilation.
1919 Returns an RTX for the address of the template. */
1921 static GTY(()) rtx initial_trampoline;
1923 #ifdef TRAMPOLINE_TEMPLATE
1925 assemble_trampoline_template (void)
1927 char label[256];
1928 const char *name;
1929 int align;
1930 rtx symbol;
1932 if (initial_trampoline)
1933 return initial_trampoline;
1935 /* By default, put trampoline templates in read-only data section. */
1937 #ifdef TRAMPOLINE_SECTION
1938 TRAMPOLINE_SECTION ();
1939 #else
1940 readonly_data_section ();
1941 #endif
1943 /* Write the assembler code to define one. */
1944 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
1945 if (align > 0)
1947 ASM_OUTPUT_ALIGN (asm_out_file, align);
1950 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
1951 TRAMPOLINE_TEMPLATE (asm_out_file);
1953 /* Record the rtl to refer to it. */
1954 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
1955 name = ggc_strdup (label);
1956 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
1957 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
1959 initial_trampoline = gen_rtx_MEM (BLKmode, symbol);
1960 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
1962 return initial_trampoline;
1964 #endif
1966 /* A and B are either alignments or offsets. Return the minimum alignment
1967 that may be assumed after adding the two together. */
1969 static inline unsigned
1970 min_align (unsigned int a, unsigned int b)
1972 return (a | b) & -(a | b);
1975 /* Return the assembler directive for creating a given kind of integer
1976 object. SIZE is the number of bytes in the object and ALIGNED_P
1977 indicates whether it is known to be aligned. Return NULL if the
1978 assembly dialect has no such directive.
1980 The returned string should be printed at the start of a new line and
1981 be followed immediately by the object's initial value. */
1983 const char *
1984 integer_asm_op (int size, int aligned_p)
1986 struct asm_int_op *ops;
1988 if (aligned_p)
1989 ops = &targetm.asm_out.aligned_op;
1990 else
1991 ops = &targetm.asm_out.unaligned_op;
1993 switch (size)
1995 case 1:
1996 return targetm.asm_out.byte_op;
1997 case 2:
1998 return ops->hi;
1999 case 4:
2000 return ops->si;
2001 case 8:
2002 return ops->di;
2003 case 16:
2004 return ops->ti;
2005 default:
2006 return NULL;
2010 /* Use directive OP to assemble an integer object X. Print OP at the
2011 start of the line, followed immediately by the value of X. */
2013 void
2014 assemble_integer_with_op (const char *op, rtx x)
2016 fputs (op, asm_out_file);
2017 output_addr_const (asm_out_file, x);
2018 fputc ('\n', asm_out_file);
2021 /* The default implementation of the asm_out.integer target hook. */
2023 bool
2024 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
2025 unsigned int size ATTRIBUTE_UNUSED,
2026 int aligned_p ATTRIBUTE_UNUSED)
2028 const char *op = integer_asm_op (size, aligned_p);
2029 /* Avoid GAS bugs for large values. Specifically negative values whose
2030 absolute value fits in a bfd_vma, but not in a bfd_signed_vma. */
2031 if (size > UNITS_PER_WORD && size > POINTER_SIZE / BITS_PER_UNIT)
2032 return false;
2033 return op && (assemble_integer_with_op (op, x), true);
2036 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
2037 the alignment of the integer in bits. Return 1 if we were able to output
2038 the constant, otherwise 0. If FORCE is nonzero, abort if we can't output
2039 the constant. */
2041 bool
2042 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
2044 int aligned_p;
2046 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
2048 /* See if the target hook can handle this kind of object. */
2049 if (targetm.asm_out.integer (x, size, aligned_p))
2050 return true;
2052 /* If the object is a multi-byte one, try splitting it up. Split
2053 it into words it if is multi-word, otherwise split it into bytes. */
2054 if (size > 1)
2056 enum machine_mode omode, imode;
2057 unsigned int subalign;
2058 unsigned int subsize, i;
2060 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2061 subalign = MIN (align, subsize * BITS_PER_UNIT);
2062 omode = mode_for_size (subsize * BITS_PER_UNIT, MODE_INT, 0);
2063 imode = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
2065 for (i = 0; i < size; i += subsize)
2067 rtx partial = simplify_subreg (omode, x, imode, i);
2068 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2069 break;
2071 if (i == size)
2072 return true;
2074 /* If we've printed some of it, but not all of it, there's no going
2075 back now. */
2076 if (i > 0)
2077 abort ();
2080 if (force)
2081 abort ();
2083 return false;
2086 void
2087 assemble_real (REAL_VALUE_TYPE d, enum machine_mode mode, unsigned int align)
2089 long data[4];
2090 int i;
2091 int bitsize, nelts, nunits, units_per;
2093 /* This is hairy. We have a quantity of known size. real_to_target
2094 will put it into an array of *host* longs, 32 bits per element
2095 (even if long is more than 32 bits). We need to determine the
2096 number of array elements that are occupied (nelts) and the number
2097 of *target* min-addressable units that will be occupied in the
2098 object file (nunits). We cannot assume that 32 divides the
2099 mode's bitsize (size * BITS_PER_UNIT) evenly.
2101 size * BITS_PER_UNIT is used here to make sure that padding bits
2102 (which might appear at either end of the value; real_to_target
2103 will include the padding bits in its output array) are included. */
2105 nunits = GET_MODE_SIZE (mode);
2106 bitsize = nunits * BITS_PER_UNIT;
2107 nelts = CEIL (bitsize, 32);
2108 units_per = 32 / BITS_PER_UNIT;
2110 real_to_target (data, &d, mode);
2112 /* Put out the first word with the specified alignment. */
2113 assemble_integer (GEN_INT (data[0]), MIN (nunits, units_per), align, 1);
2114 nunits -= units_per;
2116 /* Subsequent words need only 32-bit alignment. */
2117 align = min_align (align, 32);
2119 for (i = 1; i < nelts; i++)
2121 assemble_integer (GEN_INT (data[i]), MIN (nunits, units_per), align, 1);
2122 nunits -= units_per;
2126 /* Given an expression EXP with a constant value,
2127 reduce it to the sum of an assembler symbol and an integer.
2128 Store them both in the structure *VALUE.
2129 Abort if EXP does not reduce. */
2131 struct addr_const GTY(())
2133 rtx base;
2134 HOST_WIDE_INT offset;
2137 static void
2138 decode_addr_const (tree exp, struct addr_const *value)
2140 tree target = TREE_OPERAND (exp, 0);
2141 int offset = 0;
2142 rtx x;
2144 while (1)
2146 if (TREE_CODE (target) == COMPONENT_REF
2147 && host_integerp (byte_position (TREE_OPERAND (target, 1)), 0))
2150 offset += int_byte_position (TREE_OPERAND (target, 1));
2151 target = TREE_OPERAND (target, 0);
2153 else if (TREE_CODE (target) == ARRAY_REF
2154 || TREE_CODE (target) == ARRAY_RANGE_REF)
2156 offset += (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (target)), 1)
2157 * tree_low_cst (TREE_OPERAND (target, 1), 0));
2158 target = TREE_OPERAND (target, 0);
2160 else
2161 break;
2164 switch (TREE_CODE (target))
2166 case VAR_DECL:
2167 case FUNCTION_DECL:
2168 x = DECL_RTL (target);
2169 break;
2171 case LABEL_DECL:
2172 x = gen_rtx_MEM (FUNCTION_MODE,
2173 gen_rtx_LABEL_REF (VOIDmode, force_label_rtx (target)));
2174 break;
2176 case REAL_CST:
2177 case STRING_CST:
2178 case COMPLEX_CST:
2179 case CONSTRUCTOR:
2180 case INTEGER_CST:
2181 x = output_constant_def (target, 1);
2182 break;
2184 default:
2185 abort ();
2188 if (!MEM_P (x))
2189 abort ();
2190 x = XEXP (x, 0);
2192 value->base = x;
2193 value->offset = offset;
2196 /* Uniquize all constants that appear in memory.
2197 Each constant in memory thus far output is recorded
2198 in `const_desc_table'. */
2200 struct constant_descriptor_tree GTY(())
2202 /* A MEM for the constant. */
2203 rtx rtl;
2205 /* The value of the constant. */
2206 tree value;
2209 static GTY((param_is (struct constant_descriptor_tree)))
2210 htab_t const_desc_htab;
2212 static struct constant_descriptor_tree * build_constant_desc (tree);
2213 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2215 /* Compute a hash code for a constant expression. */
2217 static hashval_t
2218 const_desc_hash (const void *ptr)
2220 return const_hash_1 (((struct constant_descriptor_tree *)ptr)->value);
2223 static hashval_t
2224 const_hash_1 (const tree exp)
2226 const char *p;
2227 hashval_t hi;
2228 int len, i;
2229 enum tree_code code = TREE_CODE (exp);
2231 /* Either set P and LEN to the address and len of something to hash and
2232 exit the switch or return a value. */
2234 switch (code)
2236 case INTEGER_CST:
2237 p = (char *) &TREE_INT_CST (exp);
2238 len = sizeof TREE_INT_CST (exp);
2239 break;
2241 case REAL_CST:
2242 return real_hash (TREE_REAL_CST_PTR (exp));
2244 case STRING_CST:
2245 p = TREE_STRING_POINTER (exp);
2246 len = TREE_STRING_LENGTH (exp);
2247 break;
2249 case COMPLEX_CST:
2250 return (const_hash_1 (TREE_REALPART (exp)) * 5
2251 + const_hash_1 (TREE_IMAGPART (exp)));
2253 case CONSTRUCTOR:
2254 if (TREE_CODE (TREE_TYPE (exp)) == SET_TYPE)
2256 char *tmp;
2258 len = int_size_in_bytes (TREE_TYPE (exp));
2259 tmp = alloca (len);
2260 get_set_constructor_bytes (exp, (unsigned char *) tmp, len);
2261 p = tmp;
2262 break;
2264 else
2266 tree link;
2268 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2270 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link))
2271 if (TREE_VALUE (link))
2272 hi = hi * 603 + const_hash_1 (TREE_VALUE (link));
2274 return hi;
2277 case ADDR_EXPR:
2278 case FDESC_EXPR:
2280 struct addr_const value;
2282 decode_addr_const (exp, &value);
2283 if (GET_CODE (value.base) == SYMBOL_REF)
2285 /* Don't hash the address of the SYMBOL_REF;
2286 only use the offset and the symbol name. */
2287 hi = value.offset;
2288 p = XSTR (value.base, 0);
2289 for (i = 0; p[i] != 0; i++)
2290 hi = ((hi * 613) + (unsigned) (p[i]));
2292 else if (GET_CODE (value.base) == LABEL_REF)
2293 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13;
2294 else
2295 abort ();
2297 return hi;
2299 case PLUS_EXPR:
2300 case MINUS_EXPR:
2301 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2302 + const_hash_1 (TREE_OPERAND (exp, 1)));
2304 case NOP_EXPR:
2305 case CONVERT_EXPR:
2306 case NON_LVALUE_EXPR:
2307 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
2309 default:
2310 /* A language specific constant. Just hash the code. */
2311 return code;
2314 /* Compute hashing function. */
2315 hi = len;
2316 for (i = 0; i < len; i++)
2317 hi = ((hi * 613) + (unsigned) (p[i]));
2319 return hi;
2322 /* Wrapper of compare_constant, for the htab interface. */
2323 static int
2324 const_desc_eq (const void *p1, const void *p2)
2326 return compare_constant (((struct constant_descriptor_tree *)p1)->value,
2327 ((struct constant_descriptor_tree *)p2)->value);
2330 /* Compare t1 and t2, and return 1 only if they are known to result in
2331 the same bit pattern on output. */
2333 static int
2334 compare_constant (const tree t1, const tree t2)
2336 enum tree_code typecode;
2338 if (t1 == NULL_TREE)
2339 return t2 == NULL_TREE;
2340 if (t2 == NULL_TREE)
2341 return 0;
2343 if (TREE_CODE (t1) != TREE_CODE (t2))
2344 return 0;
2346 switch (TREE_CODE (t1))
2348 case INTEGER_CST:
2349 /* Integer constants are the same only if the same width of type. */
2350 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2351 return 0;
2352 return tree_int_cst_equal (t1, t2);
2354 case REAL_CST:
2355 /* Real constants are the same only if the same width of type. */
2356 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2357 return 0;
2359 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
2361 case STRING_CST:
2362 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2363 return 0;
2365 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
2366 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
2367 TREE_STRING_LENGTH (t1)));
2369 case COMPLEX_CST:
2370 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
2371 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
2373 case CONSTRUCTOR:
2374 typecode = TREE_CODE (TREE_TYPE (t1));
2375 if (typecode != TREE_CODE (TREE_TYPE (t2)))
2376 return 0;
2378 if (typecode == SET_TYPE)
2380 int len = int_size_in_bytes (TREE_TYPE (t2));
2381 unsigned char *tmp1, *tmp2;
2383 if (int_size_in_bytes (TREE_TYPE (t1)) != len)
2384 return 0;
2386 tmp1 = alloca (len);
2387 tmp2 = alloca (len);
2389 if (get_set_constructor_bytes (t1, tmp1, len) != NULL_TREE)
2390 return 0;
2391 if (get_set_constructor_bytes (t2, tmp2, len) != NULL_TREE)
2392 return 0;
2394 return memcmp (tmp1, tmp2, len) == 0;
2396 else
2398 tree l1, l2;
2400 if (typecode == ARRAY_TYPE)
2402 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
2403 /* For arrays, check that the sizes all match. */
2404 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
2405 || size_1 == -1
2406 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
2407 return 0;
2409 else
2411 /* For record and union constructors, require exact type
2412 equality. */
2413 if (TREE_TYPE (t1) != TREE_TYPE (t2))
2414 return 0;
2417 for (l1 = CONSTRUCTOR_ELTS (t1), l2 = CONSTRUCTOR_ELTS (t2);
2418 l1 && l2;
2419 l1 = TREE_CHAIN (l1), l2 = TREE_CHAIN (l2))
2421 /* Check that each value is the same... */
2422 if (! compare_constant (TREE_VALUE (l1), TREE_VALUE (l2)))
2423 return 0;
2424 /* ... and that they apply to the same fields! */
2425 if (typecode == ARRAY_TYPE)
2427 if (! compare_constant (TREE_PURPOSE (l1),
2428 TREE_PURPOSE (l2)))
2429 return 0;
2431 else
2433 if (TREE_PURPOSE (l1) != TREE_PURPOSE (l2))
2434 return 0;
2438 return l1 == NULL_TREE && l2 == NULL_TREE;
2441 case ADDR_EXPR:
2442 case FDESC_EXPR:
2444 struct addr_const value1, value2;
2446 decode_addr_const (t1, &value1);
2447 decode_addr_const (t2, &value2);
2448 return (value1.offset == value2.offset
2449 && strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
2452 case PLUS_EXPR:
2453 case MINUS_EXPR:
2454 case RANGE_EXPR:
2455 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
2456 && compare_constant(TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
2458 case NOP_EXPR:
2459 case CONVERT_EXPR:
2460 case NON_LVALUE_EXPR:
2461 case VIEW_CONVERT_EXPR:
2462 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
2464 default:
2466 tree nt1, nt2;
2467 nt1 = lang_hooks.expand_constant (t1);
2468 nt2 = lang_hooks.expand_constant (t2);
2469 if (nt1 != t1 || nt2 != t2)
2470 return compare_constant (nt1, nt2);
2471 else
2472 return 0;
2476 /* Should not get here. */
2477 abort ();
2480 /* Make a copy of the whole tree structure for a constant. This
2481 handles the same types of nodes that compare_constant handles. */
2483 static tree
2484 copy_constant (tree exp)
2486 switch (TREE_CODE (exp))
2488 case ADDR_EXPR:
2489 /* For ADDR_EXPR, we do not want to copy the decl whose address
2490 is requested. We do want to copy constants though. */
2491 if (CONSTANT_CLASS_P (TREE_OPERAND (exp, 0)))
2492 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
2493 copy_constant (TREE_OPERAND (exp, 0)));
2494 else
2495 return copy_node (exp);
2497 case INTEGER_CST:
2498 case REAL_CST:
2499 case STRING_CST:
2500 return copy_node (exp);
2502 case COMPLEX_CST:
2503 return build_complex (TREE_TYPE (exp),
2504 copy_constant (TREE_REALPART (exp)),
2505 copy_constant (TREE_IMAGPART (exp)));
2507 case PLUS_EXPR:
2508 case MINUS_EXPR:
2509 return build2 (TREE_CODE (exp), TREE_TYPE (exp),
2510 copy_constant (TREE_OPERAND (exp, 0)),
2511 copy_constant (TREE_OPERAND (exp, 1)));
2513 case NOP_EXPR:
2514 case CONVERT_EXPR:
2515 case NON_LVALUE_EXPR:
2516 case VIEW_CONVERT_EXPR:
2517 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
2518 copy_constant (TREE_OPERAND (exp, 0)));
2520 case CONSTRUCTOR:
2522 tree copy = copy_node (exp);
2523 tree list = copy_list (CONSTRUCTOR_ELTS (exp));
2524 tree tail;
2526 CONSTRUCTOR_ELTS (copy) = list;
2527 for (tail = list; tail; tail = TREE_CHAIN (tail))
2528 TREE_VALUE (tail) = copy_constant (TREE_VALUE (tail));
2529 if (TREE_CODE (TREE_TYPE (exp)) == SET_TYPE)
2530 for (tail = list; tail; tail = TREE_CHAIN (tail))
2531 TREE_PURPOSE (tail) = copy_constant (TREE_PURPOSE (tail));
2533 return copy;
2536 default:
2538 tree t;
2539 t = lang_hooks.expand_constant (exp);
2540 if (t != exp)
2541 return copy_constant (t);
2542 else
2543 abort ();
2548 /* Subroutine of output_constant_def:
2549 No constant equal to EXP is known to have been output.
2550 Make a constant descriptor to enter EXP in the hash table.
2551 Assign the label number and construct RTL to refer to the
2552 constant's location in memory.
2553 Caller is responsible for updating the hash table. */
2555 static struct constant_descriptor_tree *
2556 build_constant_desc (tree exp)
2558 rtx symbol;
2559 rtx rtl;
2560 char label[256];
2561 int labelno;
2562 struct constant_descriptor_tree *desc;
2564 desc = ggc_alloc (sizeof (*desc));
2565 desc->value = copy_constant (exp);
2567 /* Propagate marked-ness to copied constant. */
2568 if (flag_mudflap && mf_marked_p (exp))
2569 mf_mark (desc->value);
2571 /* Create a string containing the label name, in LABEL. */
2572 labelno = const_labelno++;
2573 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
2575 /* We have a symbol name; construct the SYMBOL_REF and the MEM. */
2576 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
2577 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2578 SYMBOL_REF_DECL (symbol) = desc->value;
2579 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
2581 rtl = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)), symbol);
2582 set_mem_attributes (rtl, exp, 1);
2583 set_mem_alias_set (rtl, 0);
2584 set_mem_alias_set (rtl, const_alias_set);
2586 /* Set flags or add text to the name to record information, such as
2587 that it is a local symbol. If the name is changed, the macro
2588 ASM_OUTPUT_LABELREF will have to know how to strip this
2589 information. This call might invalidate our local variable
2590 SYMBOL; we can't use it afterward. */
2592 targetm.encode_section_info (exp, rtl, true);
2594 desc->rtl = rtl;
2596 return desc;
2599 /* Return an rtx representing a reference to constant data in memory
2600 for the constant expression EXP.
2602 If assembler code for such a constant has already been output,
2603 return an rtx to refer to it.
2604 Otherwise, output such a constant in memory
2605 and generate an rtx for it.
2607 If DEFER is nonzero, this constant can be deferred and output only
2608 if referenced in the function after all optimizations.
2610 `const_desc_table' records which constants already have label strings. */
2613 output_constant_def (tree exp, int defer)
2615 struct constant_descriptor_tree *desc;
2616 struct constant_descriptor_tree key;
2617 void **loc;
2619 /* Look up EXP in the table of constant descriptors. If we didn't find
2620 it, create a new one. */
2621 key.value = exp;
2622 loc = htab_find_slot (const_desc_htab, &key, INSERT);
2624 desc = *loc;
2625 if (desc == 0)
2627 desc = build_constant_desc (exp);
2628 *loc = desc;
2631 maybe_output_constant_def_contents (desc, defer);
2632 return desc->rtl;
2635 /* Subroutine of output_constant_def: Decide whether or not we need to
2636 output the constant DESC now, and if so, do it. */
2637 static void
2638 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
2639 int defer)
2641 rtx symbol = XEXP (desc->rtl, 0);
2642 tree exp = desc->value;
2644 if (flag_syntax_only)
2645 return;
2647 if (TREE_ASM_WRITTEN (exp))
2648 /* Already output; don't do it again. */
2649 return;
2651 /* We can always defer constants as long as the context allows
2652 doing so. */
2653 if (defer)
2655 /* Increment n_deferred_constants if it exists. It needs to be at
2656 least as large as the number of constants actually referred to
2657 by the function. If it's too small we'll stop looking too early
2658 and fail to emit constants; if it's too large we'll only look
2659 through the entire function when we could have stopped earlier. */
2660 if (cfun)
2661 n_deferred_constants++;
2662 return;
2665 output_constant_def_contents (symbol);
2668 /* We must output the constant data referred to by SYMBOL; do so. */
2670 static void
2671 output_constant_def_contents (rtx symbol)
2673 tree exp = SYMBOL_REF_DECL (symbol);
2674 const char *label = XSTR (symbol, 0);
2675 HOST_WIDE_INT size;
2677 /* Make sure any other constants whose addresses appear in EXP
2678 are assigned label numbers. */
2679 int reloc = compute_reloc_for_constant (exp);
2681 /* Align the location counter as required by EXP's data type. */
2682 unsigned int align = TYPE_ALIGN (TREE_TYPE (exp));
2683 #ifdef CONSTANT_ALIGNMENT
2684 align = CONSTANT_ALIGNMENT (exp, align);
2685 #endif
2687 output_addressed_constants (exp);
2689 /* We are no longer deferring this constant. */
2690 TREE_ASM_WRITTEN (exp) = 1;
2692 if (IN_NAMED_SECTION (exp))
2693 named_section (exp, NULL, reloc);
2694 else
2695 targetm.asm_out.select_section (exp, reloc, align);
2697 if (align > BITS_PER_UNIT)
2699 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2702 size = int_size_in_bytes (TREE_TYPE (exp));
2703 if (TREE_CODE (exp) == STRING_CST)
2704 size = MAX (TREE_STRING_LENGTH (exp), size);
2706 /* Do any machine/system dependent processing of the constant. */
2707 #ifdef ASM_DECLARE_CONSTANT_NAME
2708 ASM_DECLARE_CONSTANT_NAME (asm_out_file, label, exp, size);
2709 #else
2710 /* Standard thing is just output label for the constant. */
2711 ASM_OUTPUT_LABEL (asm_out_file, label);
2712 #endif /* ASM_DECLARE_CONSTANT_NAME */
2714 /* Output the value of EXP. */
2715 output_constant (exp, size, align);
2716 if (flag_mudflap)
2717 mudflap_enqueue_constant (exp);
2720 /* Look up EXP in the table of constant descriptors. Return the rtl
2721 if it has been emitted, else null. */
2724 lookup_constant_def (tree exp)
2726 struct constant_descriptor_tree *desc;
2727 struct constant_descriptor_tree key;
2729 key.value = exp;
2730 desc = htab_find (const_desc_htab, &key);
2732 return (desc ? desc->rtl : NULL_RTX);
2735 /* Used in the hash tables to avoid outputting the same constant
2736 twice. Unlike 'struct constant_descriptor_tree', RTX constants
2737 are output once per function, not once per file. */
2738 /* ??? Only a few targets need per-function constant pools. Most
2739 can use one per-file pool. Should add a targetm bit to tell the
2740 difference. */
2742 struct rtx_constant_pool GTY(())
2744 /* Pointers to first and last constant in pool, as ordered by offset. */
2745 struct constant_descriptor_rtx *first;
2746 struct constant_descriptor_rtx *last;
2748 /* Hash facility for making memory-constants from constant rtl-expressions.
2749 It is used on RISC machines where immediate integer arguments and
2750 constant addresses are restricted so that such constants must be stored
2751 in memory. */
2752 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_htab;
2753 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_sym_htab;
2755 /* Current offset in constant pool (does not include any
2756 machine-specific header). */
2757 HOST_WIDE_INT offset;
2760 struct constant_descriptor_rtx GTY((chain_next ("%h.next")))
2762 struct constant_descriptor_rtx *next;
2763 rtx mem;
2764 rtx sym;
2765 rtx constant;
2766 HOST_WIDE_INT offset;
2767 hashval_t hash;
2768 enum machine_mode mode;
2769 unsigned int align;
2770 int labelno;
2771 int mark;
2774 /* Hash and compare functions for const_rtx_htab. */
2776 static hashval_t
2777 const_desc_rtx_hash (const void *ptr)
2779 const struct constant_descriptor_rtx *desc = ptr;
2780 return desc->hash;
2783 static int
2784 const_desc_rtx_eq (const void *a, const void *b)
2786 const struct constant_descriptor_rtx *x = a;
2787 const struct constant_descriptor_rtx *y = b;
2789 if (x->mode != y->mode)
2790 return 0;
2791 return rtx_equal_p (x->constant, y->constant);
2794 /* Hash and compare functions for const_rtx_sym_htab. */
2796 static hashval_t
2797 const_desc_rtx_sym_hash (const void *ptr)
2799 const struct constant_descriptor_rtx *desc = ptr;
2800 return htab_hash_string (XSTR (desc->sym, 0));
2803 static int
2804 const_desc_rtx_sym_eq (const void *a, const void *b)
2806 const struct constant_descriptor_rtx *x = a;
2807 const struct constant_descriptor_rtx *y = b;
2808 return XSTR (x->sym, 0) == XSTR (y->sym, 0);
2811 /* This is the worker function for const_rtx_hash, called via for_each_rtx. */
2813 static int
2814 const_rtx_hash_1 (rtx *xp, void *data)
2816 unsigned HOST_WIDE_INT hwi;
2817 enum machine_mode mode;
2818 enum rtx_code code;
2819 hashval_t h, *hp;
2820 rtx x;
2822 x = *xp;
2823 code = GET_CODE (x);
2824 mode = GET_MODE (x);
2825 h = (hashval_t) code * 1048573 + mode;
2827 switch (code)
2829 case CONST_INT:
2830 hwi = INTVAL (x);
2831 fold_hwi:
2833 const int shift = sizeof (hashval_t) * CHAR_BIT;
2834 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
2835 int i;
2837 h ^= (hashval_t) hwi;
2838 for (i = 1; i < n; ++i)
2840 hwi >>= shift;
2841 h ^= (hashval_t) hwi;
2844 break;
2846 case CONST_DOUBLE:
2847 if (mode == VOIDmode)
2849 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
2850 goto fold_hwi;
2852 else
2853 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
2854 break;
2856 case SYMBOL_REF:
2857 h ^= htab_hash_string (XSTR (x, 0));
2858 break;
2860 case LABEL_REF:
2861 h = h * 251 + CODE_LABEL_NUMBER (XEXP (x, 0));
2862 break;
2864 case UNSPEC:
2865 case UNSPEC_VOLATILE:
2866 h = h * 251 + XINT (x, 1);
2867 break;
2869 default:
2870 break;
2873 hp = data;
2874 *hp = *hp * 509 + h;
2875 return 0;
2878 /* Compute a hash value for X, which should be a constant. */
2880 static hashval_t
2881 const_rtx_hash (rtx x)
2883 hashval_t h = 0;
2884 for_each_rtx (&x, const_rtx_hash_1, &h);
2885 return h;
2889 /* Initialize constant pool hashing for a new function. */
2891 void
2892 init_varasm_status (struct function *f)
2894 struct varasm_status *p;
2895 struct rtx_constant_pool *pool;
2897 p = ggc_alloc (sizeof (struct varasm_status));
2898 f->varasm = p;
2900 pool = ggc_alloc (sizeof (struct rtx_constant_pool));
2901 p->pool = pool;
2902 p->deferred_constants = 0;
2904 pool->const_rtx_htab = htab_create_ggc (31, const_desc_rtx_hash,
2905 const_desc_rtx_eq, NULL);
2906 pool->const_rtx_sym_htab = htab_create_ggc (31, const_desc_rtx_sym_hash,
2907 const_desc_rtx_sym_eq, NULL);
2908 pool->first = pool->last = NULL;
2909 pool->offset = 0;
2912 /* Given a MINUS expression, simplify it if both sides
2913 include the same symbol. */
2916 simplify_subtraction (rtx x)
2918 rtx r = simplify_rtx (x);
2919 return r ? r : x;
2922 /* Given a constant rtx X, make (or find) a memory constant for its value
2923 and return a MEM rtx to refer to it in memory. */
2926 force_const_mem (enum machine_mode mode, rtx x)
2928 struct constant_descriptor_rtx *desc, tmp;
2929 struct rtx_constant_pool *pool = cfun->varasm->pool;
2930 char label[256];
2931 rtx def, symbol;
2932 hashval_t hash;
2933 unsigned int align;
2934 void **slot;
2936 /* If we're not allowed to drop X into the constant pool, don't. */
2937 if (targetm.cannot_force_const_mem (x))
2938 return NULL_RTX;
2940 /* Lookup the value in the hashtable. */
2941 tmp.constant = x;
2942 tmp.mode = mode;
2943 hash = const_rtx_hash (x);
2944 slot = htab_find_slot_with_hash (pool->const_rtx_htab, &tmp, hash, INSERT);
2945 desc = *slot;
2947 /* If the constant was already present, return its memory. */
2948 if (desc)
2949 return copy_rtx (desc->mem);
2951 /* Otherwise, create a new descriptor. */
2952 desc = ggc_alloc (sizeof (*desc));
2953 *slot = desc;
2955 /* Align the location counter as required by EXP's data type. */
2956 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
2957 #ifdef CONSTANT_ALIGNMENT
2959 tree type = lang_hooks.types.type_for_mode (mode, 0);
2960 if (type != NULL_TREE)
2961 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
2963 #endif
2965 pool->offset += (align / BITS_PER_UNIT) - 1;
2966 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
2968 desc->next = NULL;
2969 desc->constant = tmp.constant;
2970 desc->offset = pool->offset;
2971 desc->hash = hash;
2972 desc->mode = mode;
2973 desc->align = align;
2974 desc->labelno = const_labelno;
2975 desc->mark = 0;
2977 pool->offset += GET_MODE_SIZE (mode);
2978 if (pool->last)
2979 pool->last->next = desc;
2980 else
2981 pool->first = pool->last = desc;
2982 pool->last = desc;
2984 /* Create a string containing the label name, in LABEL. */
2985 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
2986 ++const_labelno;
2988 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
2989 the constants pool. */
2990 desc->sym = symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
2991 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2992 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
2993 current_function_uses_const_pool = 1;
2995 /* Insert the descriptor into the symbol cross-reference table too. */
2996 slot = htab_find_slot (pool->const_rtx_sym_htab, desc, INSERT);
2997 if (*slot)
2998 abort ();
2999 *slot = desc;
3001 /* Construct the MEM. */
3002 desc->mem = def = gen_const_mem (mode, symbol);
3003 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
3005 /* If we're dropping a label to the constant pool, make sure we
3006 don't delete it. */
3007 if (GET_CODE (x) == LABEL_REF)
3008 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3010 return copy_rtx (def);
3013 /* Given a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true, return a pointer to
3014 the corresponding constant_descriptor_rtx structure. */
3016 static struct constant_descriptor_rtx *
3017 find_pool_constant (struct rtx_constant_pool *pool, rtx sym)
3019 struct constant_descriptor_rtx tmp;
3020 tmp.sym = sym;
3021 return htab_find (pool->const_rtx_sym_htab, &tmp);
3024 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3027 get_pool_constant (rtx addr)
3029 return find_pool_constant (cfun->varasm->pool, addr)->constant;
3032 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3033 and whether it has been output or not. */
3036 get_pool_constant_mark (rtx addr, bool *pmarked)
3038 struct constant_descriptor_rtx *desc;
3040 desc = find_pool_constant (cfun->varasm->pool, addr);
3041 *pmarked = (desc->mark != 0);
3042 return desc->constant;
3045 /* Likewise, but for the constant pool of a specific function. */
3048 get_pool_constant_for_function (struct function *f, rtx addr)
3050 return find_pool_constant (f->varasm->pool, addr)->constant;
3053 /* Similar, return the mode. */
3055 enum machine_mode
3056 get_pool_mode (rtx addr)
3058 return find_pool_constant (cfun->varasm->pool, addr)->mode;
3061 /* Return the size of the constant pool. */
3064 get_pool_size (void)
3066 return cfun->varasm->pool->offset;
3069 /* Worker function for output_constant_pool_1. Emit assembly for X
3070 in MODE with known alignment ALIGN. */
3072 static void
3073 output_constant_pool_2 (enum machine_mode mode, rtx x, unsigned int align)
3075 switch (GET_MODE_CLASS (mode))
3077 case MODE_FLOAT:
3078 if (GET_CODE (x) != CONST_DOUBLE)
3079 abort ();
3080 else
3082 REAL_VALUE_TYPE r;
3083 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3084 assemble_real (r, mode, align);
3086 break;
3088 case MODE_INT:
3089 case MODE_PARTIAL_INT:
3090 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3091 break;
3093 case MODE_VECTOR_FLOAT:
3094 case MODE_VECTOR_INT:
3096 int i, units;
3097 enum machine_mode submode = GET_MODE_INNER (mode);
3098 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3100 if (GET_CODE (x) != CONST_VECTOR)
3101 abort ();
3102 units = CONST_VECTOR_NUNITS (x);
3104 for (i = 0; i < units; i++)
3106 rtx elt = CONST_VECTOR_ELT (x, i);
3107 output_constant_pool_2 (submode, elt, i ? subalign : align);
3110 break;
3112 default:
3113 abort ();
3117 /* Worker function for output_constant_pool. Emit POOL. */
3119 static void
3120 output_constant_pool_1 (struct constant_descriptor_rtx *desc)
3122 rtx x, tmp;
3124 if (!desc->mark)
3125 return;
3126 x = desc->constant;
3128 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3129 whose CODE_LABEL has been deleted. This can occur if a jump table
3130 is eliminated by optimization. If so, write a constant of zero
3131 instead. Note that this can also happen by turning the
3132 CODE_LABEL into a NOTE. */
3133 /* ??? This seems completely and utterly wrong. Certainly it's
3134 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3135 functioning even with INSN_DELETED_P and friends. */
3137 tmp = x;
3138 switch (GET_CODE (x))
3140 case CONST:
3141 if (GET_CODE (XEXP (x, 0)) != PLUS
3142 || GET_CODE (XEXP (XEXP (x, 0), 0)) != LABEL_REF)
3143 break;
3144 tmp = XEXP (XEXP (x, 0), 0);
3145 /* FALLTHRU */
3147 case LABEL_REF:
3148 tmp = XEXP (x, 0);
3149 if (INSN_DELETED_P (tmp)
3150 || (NOTE_P (tmp)
3151 && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_DELETED))
3153 abort ();
3154 x = const0_rtx;
3156 break;
3158 default:
3159 break;
3162 /* First switch to correct section. */
3163 targetm.asm_out.select_rtx_section (desc->mode, x, desc->align);
3165 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3166 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3167 desc->align, desc->labelno, done);
3168 #endif
3170 assemble_align (desc->align);
3172 /* Output the label. */
3173 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3175 /* Output the data. */
3176 output_constant_pool_2 (desc->mode, x, desc->align);
3178 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3179 sections have proper size. */
3180 if (desc->align > GET_MODE_BITSIZE (desc->mode)
3181 && in_section == in_named
3182 && get_named_section_flags (in_named_name) & SECTION_MERGE)
3183 assemble_align (desc->align);
3185 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3186 done:
3187 #endif
3188 return;
3191 /* Given a SYMBOL_REF CURRENT_RTX, mark it and all constants it refers
3192 to as used. Emit referenced deferred strings. This function can
3193 be used with for_each_rtx to mark all SYMBOL_REFs in an rtx. */
3195 static int
3196 mark_constant (rtx *current_rtx, void *data)
3198 struct rtx_constant_pool *pool = data;
3199 rtx x = *current_rtx;
3201 if (x == NULL_RTX || GET_CODE (x) != SYMBOL_REF)
3202 return 0;
3204 if (CONSTANT_POOL_ADDRESS_P (x))
3206 struct constant_descriptor_rtx *desc = find_pool_constant (pool, x);
3207 if (desc->mark == 0)
3209 desc->mark = 1;
3210 for_each_rtx (&desc->constant, mark_constant, pool);
3213 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3215 tree exp = SYMBOL_REF_DECL (x);
3216 if (!TREE_ASM_WRITTEN (exp))
3218 n_deferred_constants--;
3219 output_constant_def_contents (x);
3223 return -1;
3226 /* Look through appropriate parts of INSN, marking all entries in the
3227 constant pool which are actually being used. Entries that are only
3228 referenced by other constants are also marked as used. Emit
3229 deferred strings that are used. */
3231 static void
3232 mark_constants (struct rtx_constant_pool *pool, rtx insn)
3234 if (!INSN_P (insn))
3235 return;
3237 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3238 insns, not any notes that may be attached. We don't want to mark
3239 a constant just because it happens to appear in a REG_EQUIV note. */
3240 if (GET_CODE (PATTERN (insn)) == SEQUENCE)
3242 rtx seq = PATTERN (insn);
3243 int i, n = XVECLEN (seq, 0);
3244 for (i = 0; i < n; ++i)
3246 rtx subinsn = XVECEXP (seq, 0, i);
3247 if (INSN_P (subinsn))
3248 for_each_rtx (&PATTERN (subinsn), mark_constant, pool);
3251 else
3252 for_each_rtx (&PATTERN (insn), mark_constant, pool);
3255 /* Look through the instructions for this function, and mark all the
3256 entries in POOL which are actually being used. Emit deferred constants
3257 which have indeed been used. */
3259 static void
3260 mark_constant_pool (struct rtx_constant_pool *pool)
3262 rtx insn, link;
3264 if (pool->first == 0 && n_deferred_constants == 0)
3265 return;
3267 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3268 mark_constants (pool, insn);
3270 for (link = current_function_epilogue_delay_list;
3271 link;
3272 link = XEXP (link, 1))
3273 mark_constants (pool, XEXP (link, 0));
3276 /* Write all the constants in the constant pool. */
3278 void
3279 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
3280 tree fndecl ATTRIBUTE_UNUSED)
3282 struct rtx_constant_pool *pool = cfun->varasm->pool;
3283 struct constant_descriptor_rtx *desc;
3285 /* It is possible for gcc to call force_const_mem and then to later
3286 discard the instructions which refer to the constant. In such a
3287 case we do not need to output the constant. */
3288 mark_constant_pool (pool);
3290 #ifdef ASM_OUTPUT_POOL_PROLOGUE
3291 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
3292 #endif
3294 for (desc = pool->first; desc ; desc = desc->next)
3295 output_constant_pool_1 (desc);
3297 #ifdef ASM_OUTPUT_POOL_EPILOGUE
3298 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
3299 #endif
3302 /* Determine what kind of relocations EXP may need. */
3305 compute_reloc_for_constant (tree exp)
3307 int reloc = 0, reloc2;
3308 tree tem;
3310 /* Give the front-end a chance to convert VALUE to something that
3311 looks more like a constant to the back-end. */
3312 exp = lang_hooks.expand_constant (exp);
3314 switch (TREE_CODE (exp))
3316 case ADDR_EXPR:
3317 case FDESC_EXPR:
3318 /* Go inside any operations that get_inner_reference can handle and see
3319 if what's inside is a constant: no need to do anything here for
3320 addresses of variables or functions. */
3321 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
3322 tem = TREE_OPERAND (tem, 0))
3325 if (TREE_PUBLIC (tem))
3326 reloc |= 2;
3327 else
3328 reloc |= 1;
3329 break;
3331 case PLUS_EXPR:
3332 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3333 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
3334 break;
3336 case MINUS_EXPR:
3337 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3338 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
3339 /* The difference of two local labels is computable at link time. */
3340 if (reloc == 1 && reloc2 == 1)
3341 reloc = 0;
3342 else
3343 reloc |= reloc2;
3344 break;
3346 case NOP_EXPR:
3347 case CONVERT_EXPR:
3348 case NON_LVALUE_EXPR:
3349 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3350 break;
3352 case CONSTRUCTOR:
3353 for (tem = CONSTRUCTOR_ELTS (exp); tem; tem = TREE_CHAIN (tem))
3354 if (TREE_VALUE (tem) != 0)
3355 reloc |= compute_reloc_for_constant (TREE_VALUE (tem));
3357 break;
3359 default:
3360 break;
3362 return reloc;
3365 /* Find all the constants whose addresses are referenced inside of EXP,
3366 and make sure assembler code with a label has been output for each one.
3367 Indicate whether an ADDR_EXPR has been encountered. */
3369 static void
3370 output_addressed_constants (tree exp)
3372 tree tem;
3374 /* Give the front-end a chance to convert VALUE to something that
3375 looks more like a constant to the back-end. */
3376 exp = lang_hooks.expand_constant (exp);
3378 switch (TREE_CODE (exp))
3380 case ADDR_EXPR:
3381 case FDESC_EXPR:
3382 /* Go inside any operations that get_inner_reference can handle and see
3383 if what's inside is a constant: no need to do anything here for
3384 addresses of variables or functions. */
3385 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
3386 tem = TREE_OPERAND (tem, 0))
3389 /* If we have an initialized CONST_DECL, retrieve the initializer. */
3390 if (TREE_CODE (tem) == CONST_DECL && DECL_INITIAL (tem))
3391 tem = DECL_INITIAL (tem);
3393 if (CONSTANT_CLASS_P (tem) || TREE_CODE (tem) == CONSTRUCTOR)
3394 output_constant_def (tem, 0);
3395 break;
3397 case PLUS_EXPR:
3398 case MINUS_EXPR:
3399 output_addressed_constants (TREE_OPERAND (exp, 1));
3400 /* Fall through. */
3402 case NOP_EXPR:
3403 case CONVERT_EXPR:
3404 case NON_LVALUE_EXPR:
3405 output_addressed_constants (TREE_OPERAND (exp, 0));
3406 break;
3408 case CONSTRUCTOR:
3409 for (tem = CONSTRUCTOR_ELTS (exp); tem; tem = TREE_CHAIN (tem))
3410 if (TREE_VALUE (tem) != 0)
3411 output_addressed_constants (TREE_VALUE (tem));
3413 break;
3415 default:
3416 break;
3420 /* Return nonzero if VALUE is a valid constant-valued expression
3421 for use in initializing a static variable; one that can be an
3422 element of a "constant" initializer.
3424 Return null_pointer_node if the value is absolute;
3425 if it is relocatable, return the variable that determines the relocation.
3426 We assume that VALUE has been folded as much as possible;
3427 therefore, we do not need to check for such things as
3428 arithmetic-combinations of integers. */
3430 tree
3431 initializer_constant_valid_p (tree value, tree endtype)
3433 /* Give the front-end a chance to convert VALUE to something that
3434 looks more like a constant to the back-end. */
3435 value = lang_hooks.expand_constant (value);
3437 switch (TREE_CODE (value))
3439 case CONSTRUCTOR:
3440 if ((TREE_CODE (TREE_TYPE (value)) == UNION_TYPE
3441 || TREE_CODE (TREE_TYPE (value)) == RECORD_TYPE)
3442 && TREE_CONSTANT (value)
3443 && CONSTRUCTOR_ELTS (value))
3445 tree elt;
3446 bool absolute = true;
3448 for (elt = CONSTRUCTOR_ELTS (value); elt; elt = TREE_CHAIN (elt))
3450 tree reloc;
3451 value = TREE_VALUE (elt);
3452 reloc = initializer_constant_valid_p (value, TREE_TYPE (value));
3453 if (!reloc)
3454 return NULL_TREE;
3455 if (reloc != null_pointer_node)
3456 absolute = false;
3458 /* For a non-absolute relocation, there is no single
3459 variable that can be "the variable that determines the
3460 relocation." */
3461 return absolute ? null_pointer_node : error_mark_node;
3464 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
3466 case INTEGER_CST:
3467 case VECTOR_CST:
3468 case REAL_CST:
3469 case STRING_CST:
3470 case COMPLEX_CST:
3471 return null_pointer_node;
3473 case ADDR_EXPR:
3474 case FDESC_EXPR:
3475 value = staticp (TREE_OPERAND (value, 0));
3476 /* "&(*a).f" is like unto pointer arithmetic. If "a" turns out to
3477 be a constant, this is old-skool offsetof-like nonsense. */
3478 if (value
3479 && TREE_CODE (value) == INDIRECT_REF
3480 && TREE_CONSTANT (TREE_OPERAND (value, 0)))
3481 return null_pointer_node;
3482 return value;
3484 case VIEW_CONVERT_EXPR:
3485 case NON_LVALUE_EXPR:
3486 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3488 case CONVERT_EXPR:
3489 case NOP_EXPR:
3490 /* Allow conversions between pointer types. */
3491 if (POINTER_TYPE_P (TREE_TYPE (value))
3492 && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3493 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3495 /* Allow conversions between real types. */
3496 if (FLOAT_TYPE_P (TREE_TYPE (value))
3497 && FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3498 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3500 /* Allow length-preserving conversions between integer types. */
3501 if (INTEGRAL_TYPE_P (TREE_TYPE (value))
3502 && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0)))
3503 && (TYPE_PRECISION (TREE_TYPE (value))
3504 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0)))))
3505 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3507 /* Allow conversions between other integer types only if
3508 explicit value. */
3509 if (INTEGRAL_TYPE_P (TREE_TYPE (value))
3510 && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3512 tree inner = initializer_constant_valid_p (TREE_OPERAND (value, 0),
3513 endtype);
3514 if (inner == null_pointer_node)
3515 return null_pointer_node;
3516 break;
3519 /* Allow (int) &foo provided int is as wide as a pointer. */
3520 if (INTEGRAL_TYPE_P (TREE_TYPE (value))
3521 && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0)))
3522 && (TYPE_PRECISION (TREE_TYPE (value))
3523 >= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0)))))
3524 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
3525 endtype);
3527 /* Likewise conversions from int to pointers, but also allow
3528 conversions from 0. */
3529 if ((POINTER_TYPE_P (TREE_TYPE (value))
3530 || TREE_CODE (TREE_TYPE (value)) == OFFSET_TYPE)
3531 && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3533 if (integer_zerop (TREE_OPERAND (value, 0)))
3534 return null_pointer_node;
3535 else if (TYPE_PRECISION (TREE_TYPE (value))
3536 <= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0))))
3537 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
3538 endtype);
3541 /* Allow conversions to struct or union types if the value
3542 inside is okay. */
3543 if (TREE_CODE (TREE_TYPE (value)) == RECORD_TYPE
3544 || TREE_CODE (TREE_TYPE (value)) == UNION_TYPE)
3545 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
3546 endtype);
3547 break;
3549 case PLUS_EXPR:
3550 if (! INTEGRAL_TYPE_P (endtype)
3551 || TYPE_PRECISION (endtype) >= POINTER_SIZE)
3553 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0),
3554 endtype);
3555 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1),
3556 endtype);
3557 /* If either term is absolute, use the other terms relocation. */
3558 if (valid0 == null_pointer_node)
3559 return valid1;
3560 if (valid1 == null_pointer_node)
3561 return valid0;
3563 break;
3565 case MINUS_EXPR:
3566 if (! INTEGRAL_TYPE_P (endtype)
3567 || TYPE_PRECISION (endtype) >= POINTER_SIZE)
3569 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0),
3570 endtype);
3571 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1),
3572 endtype);
3573 /* Win if second argument is absolute. */
3574 if (valid1 == null_pointer_node)
3575 return valid0;
3576 /* Win if both arguments have the same relocation.
3577 Then the value is absolute. */
3578 if (valid0 == valid1 && valid0 != 0)
3579 return null_pointer_node;
3581 /* Since GCC guarantees that string constants are unique in the
3582 generated code, a subtraction between two copies of the same
3583 constant string is absolute. */
3584 if (valid0 && TREE_CODE (valid0) == STRING_CST
3585 && valid1 && TREE_CODE (valid1) == STRING_CST
3586 && operand_equal_p (valid0, valid1, 1))
3587 return null_pointer_node;
3590 /* Support narrowing differences. */
3591 if (INTEGRAL_TYPE_P (endtype))
3593 tree op0, op1;
3595 op0 = TREE_OPERAND (value, 0);
3596 op1 = TREE_OPERAND (value, 1);
3598 /* Like STRIP_NOPS except allow the operand mode to widen.
3599 This works around a feature of fold that simplifies
3600 (int)(p1 - p2) to ((int)p1 - (int)p2) under the theory
3601 that the narrower operation is cheaper. */
3603 while (TREE_CODE (op0) == NOP_EXPR
3604 || TREE_CODE (op0) == CONVERT_EXPR
3605 || TREE_CODE (op0) == NON_LVALUE_EXPR)
3607 tree inner = TREE_OPERAND (op0, 0);
3608 if (inner == error_mark_node
3609 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
3610 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
3611 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
3612 break;
3613 op0 = inner;
3616 while (TREE_CODE (op1) == NOP_EXPR
3617 || TREE_CODE (op1) == CONVERT_EXPR
3618 || TREE_CODE (op1) == NON_LVALUE_EXPR)
3620 tree inner = TREE_OPERAND (op1, 0);
3621 if (inner == error_mark_node
3622 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
3623 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
3624 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
3625 break;
3626 op1 = inner;
3629 op0 = initializer_constant_valid_p (op0, endtype);
3630 op1 = initializer_constant_valid_p (op1, endtype);
3632 /* Both initializers must be known. */
3633 if (op0 && op1)
3635 if (op0 == op1)
3636 return null_pointer_node;
3638 /* Support differences between labels. */
3639 if (TREE_CODE (op0) == LABEL_DECL
3640 && TREE_CODE (op1) == LABEL_DECL)
3641 return null_pointer_node;
3643 if (TREE_CODE (op0) == STRING_CST
3644 && TREE_CODE (op1) == STRING_CST
3645 && operand_equal_p (op0, op1, 1))
3646 return null_pointer_node;
3649 break;
3651 default:
3652 break;
3655 return 0;
3658 /* Output assembler code for constant EXP to FILE, with no label.
3659 This includes the pseudo-op such as ".int" or ".byte", and a newline.
3660 Assumes output_addressed_constants has been done on EXP already.
3662 Generate exactly SIZE bytes of assembler data, padding at the end
3663 with zeros if necessary. SIZE must always be specified.
3665 SIZE is important for structure constructors,
3666 since trailing members may have been omitted from the constructor.
3667 It is also important for initialization of arrays from string constants
3668 since the full length of the string constant might not be wanted.
3669 It is also needed for initialization of unions, where the initializer's
3670 type is just one member, and that may not be as long as the union.
3672 There a case in which we would fail to output exactly SIZE bytes:
3673 for a structure constructor that wants to produce more than SIZE bytes.
3674 But such constructors will never be generated for any possible input.
3676 ALIGN is the alignment of the data in bits. */
3678 void
3679 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align)
3681 enum tree_code code;
3682 unsigned HOST_WIDE_INT thissize;
3684 /* Some front-ends use constants other than the standard language-independent
3685 varieties, but which may still be output directly. Give the front-end a
3686 chance to convert EXP to a language-independent representation. */
3687 exp = lang_hooks.expand_constant (exp);
3689 if (size == 0 || flag_syntax_only)
3690 return;
3692 /* Eliminate any conversions since we'll be outputting the underlying
3693 constant. */
3694 while (TREE_CODE (exp) == NOP_EXPR || TREE_CODE (exp) == CONVERT_EXPR
3695 || TREE_CODE (exp) == NON_LVALUE_EXPR
3696 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
3697 exp = TREE_OPERAND (exp, 0);
3699 code = TREE_CODE (TREE_TYPE (exp));
3700 thissize = int_size_in_bytes (TREE_TYPE (exp));
3702 /* Allow a constructor with no elements for any data type.
3703 This means to fill the space with zeros. */
3704 if (TREE_CODE (exp) == CONSTRUCTOR && CONSTRUCTOR_ELTS (exp) == 0)
3706 assemble_zeros (size);
3707 return;
3710 if (TREE_CODE (exp) == FDESC_EXPR)
3712 #ifdef ASM_OUTPUT_FDESC
3713 HOST_WIDE_INT part = tree_low_cst (TREE_OPERAND (exp, 1), 0);
3714 tree decl = TREE_OPERAND (exp, 0);
3715 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
3716 #else
3717 abort ();
3718 #endif
3719 return;
3722 /* Now output the underlying data. If we've handling the padding, return.
3723 Otherwise, break and ensure SIZE is the size written. */
3724 switch (code)
3726 case CHAR_TYPE:
3727 case BOOLEAN_TYPE:
3728 case INTEGER_TYPE:
3729 case ENUMERAL_TYPE:
3730 case POINTER_TYPE:
3731 case REFERENCE_TYPE:
3732 case OFFSET_TYPE:
3733 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
3734 EXPAND_INITIALIZER),
3735 MIN (size, thissize), align, 0))
3736 error ("initializer for integer value is too complicated");
3737 break;
3739 case REAL_TYPE:
3740 if (TREE_CODE (exp) != REAL_CST)
3741 error ("initializer for floating value is not a floating constant");
3743 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)), align);
3744 break;
3746 case COMPLEX_TYPE:
3747 output_constant (TREE_REALPART (exp), thissize / 2, align);
3748 output_constant (TREE_IMAGPART (exp), thissize / 2,
3749 min_align (align, BITS_PER_UNIT * (thissize / 2)));
3750 break;
3752 case ARRAY_TYPE:
3753 case VECTOR_TYPE:
3754 if (TREE_CODE (exp) == CONSTRUCTOR)
3756 output_constructor (exp, size, align);
3757 return;
3759 else if (TREE_CODE (exp) == STRING_CST)
3761 thissize = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp),
3762 size);
3763 assemble_string (TREE_STRING_POINTER (exp), thissize);
3765 else if (TREE_CODE (exp) == VECTOR_CST)
3767 int elt_size;
3768 tree link;
3769 unsigned int nalign;
3770 enum machine_mode inner;
3772 inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
3773 nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
3775 elt_size = GET_MODE_SIZE (inner);
3777 link = TREE_VECTOR_CST_ELTS (exp);
3778 output_constant (TREE_VALUE (link), elt_size, align);
3779 while ((link = TREE_CHAIN (link)) != NULL)
3780 output_constant (TREE_VALUE (link), elt_size, nalign);
3782 else
3783 abort ();
3784 break;
3786 case RECORD_TYPE:
3787 case UNION_TYPE:
3788 if (TREE_CODE (exp) == CONSTRUCTOR)
3789 output_constructor (exp, size, align);
3790 else
3791 abort ();
3792 return;
3794 case SET_TYPE:
3795 if (TREE_CODE (exp) == INTEGER_CST)
3796 assemble_integer (expand_expr (exp, NULL_RTX,
3797 VOIDmode, EXPAND_INITIALIZER),
3798 thissize, align, 1);
3799 else if (TREE_CODE (exp) == CONSTRUCTOR)
3801 unsigned char *buffer = alloca (thissize);
3802 if (get_set_constructor_bytes (exp, buffer, thissize))
3803 abort ();
3804 assemble_string ((char *) buffer, thissize);
3806 else
3807 error ("unknown set constructor type");
3808 return;
3810 case ERROR_MARK:
3811 return;
3813 default:
3814 abort ();
3817 if (size > thissize)
3818 assemble_zeros (size - thissize);
3822 /* Subroutine of output_constructor, used for computing the size of
3823 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
3824 type with an unspecified upper bound. */
3826 static unsigned HOST_WIDE_INT
3827 array_size_for_constructor (tree val)
3829 tree max_index, i;
3831 /* This code used to attempt to handle string constants that are not
3832 arrays of single-bytes, but nothing else does, so there's no point in
3833 doing it here. */
3834 if (TREE_CODE (val) == STRING_CST)
3835 return TREE_STRING_LENGTH (val);
3837 max_index = NULL_TREE;
3838 for (i = CONSTRUCTOR_ELTS (val); i; i = TREE_CHAIN (i))
3840 tree index = TREE_PURPOSE (i);
3842 if (TREE_CODE (index) == RANGE_EXPR)
3843 index = TREE_OPERAND (index, 1);
3844 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
3845 max_index = index;
3848 if (max_index == NULL_TREE)
3849 return 0;
3851 /* Compute the total number of array elements. */
3852 i = size_binop (MINUS_EXPR, convert (sizetype, max_index),
3853 convert (sizetype,
3854 TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)))));
3855 i = size_binop (PLUS_EXPR, i, convert (sizetype, integer_one_node));
3857 /* Multiply by the array element unit size to find number of bytes. */
3858 i = size_binop (MULT_EXPR, i, TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
3860 return tree_low_cst (i, 1);
3863 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
3864 Generate at least SIZE bytes, padding if necessary. */
3866 static void
3867 output_constructor (tree exp, unsigned HOST_WIDE_INT size,
3868 unsigned int align)
3870 tree type = TREE_TYPE (exp);
3871 tree link, field = 0;
3872 tree min_index = 0;
3873 /* Number of bytes output or skipped so far.
3874 In other words, current position within the constructor. */
3875 HOST_WIDE_INT total_bytes = 0;
3876 /* Nonzero means BYTE contains part of a byte, to be output. */
3877 int byte_buffer_in_use = 0;
3878 int byte = 0;
3880 if (HOST_BITS_PER_WIDE_INT < BITS_PER_UNIT)
3881 abort ();
3883 if (TREE_CODE (type) == RECORD_TYPE)
3884 field = TYPE_FIELDS (type);
3886 if (TREE_CODE (type) == ARRAY_TYPE
3887 && TYPE_DOMAIN (type) != 0)
3888 min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (type));
3890 /* As LINK goes through the elements of the constant,
3891 FIELD goes through the structure fields, if the constant is a structure.
3892 if the constant is a union, then we override this,
3893 by getting the field from the TREE_LIST element.
3894 But the constant could also be an array. Then FIELD is zero.
3896 There is always a maximum of one element in the chain LINK for unions
3897 (even if the initializer in a source program incorrectly contains
3898 more one). */
3899 for (link = CONSTRUCTOR_ELTS (exp);
3900 link;
3901 link = TREE_CHAIN (link),
3902 field = field ? TREE_CHAIN (field) : 0)
3904 tree val = TREE_VALUE (link);
3905 tree index = 0;
3907 /* The element in a union constructor specifies the proper field
3908 or index. */
3909 if ((TREE_CODE (type) == RECORD_TYPE || TREE_CODE (type) == UNION_TYPE
3910 || TREE_CODE (type) == QUAL_UNION_TYPE)
3911 && TREE_PURPOSE (link) != 0)
3912 field = TREE_PURPOSE (link);
3914 else if (TREE_CODE (type) == ARRAY_TYPE)
3915 index = TREE_PURPOSE (link);
3917 #ifdef ASM_COMMENT_START
3918 if (field && flag_verbose_asm)
3919 fprintf (asm_out_file, "%s %s:\n",
3920 ASM_COMMENT_START,
3921 DECL_NAME (field)
3922 ? IDENTIFIER_POINTER (DECL_NAME (field))
3923 : "<anonymous>");
3924 #endif
3926 /* Eliminate the marker that makes a cast not be an lvalue. */
3927 if (val != 0)
3928 STRIP_NOPS (val);
3930 if (index && TREE_CODE (index) == RANGE_EXPR)
3932 unsigned HOST_WIDE_INT fieldsize
3933 = int_size_in_bytes (TREE_TYPE (type));
3934 HOST_WIDE_INT lo_index = tree_low_cst (TREE_OPERAND (index, 0), 0);
3935 HOST_WIDE_INT hi_index = tree_low_cst (TREE_OPERAND (index, 1), 0);
3936 HOST_WIDE_INT index;
3937 unsigned int align2 = min_align (align, fieldsize * BITS_PER_UNIT);
3939 for (index = lo_index; index <= hi_index; index++)
3941 /* Output the element's initial value. */
3942 if (val == 0)
3943 assemble_zeros (fieldsize);
3944 else
3945 output_constant (val, fieldsize, align2);
3947 /* Count its size. */
3948 total_bytes += fieldsize;
3951 else if (field == 0 || !DECL_BIT_FIELD (field))
3953 /* An element that is not a bit-field. */
3955 unsigned HOST_WIDE_INT fieldsize;
3956 /* Since this structure is static,
3957 we know the positions are constant. */
3958 HOST_WIDE_INT pos = field ? int_byte_position (field) : 0;
3959 unsigned int align2;
3961 if (index != 0)
3962 pos = (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (val)), 1)
3963 * (tree_low_cst (index, 0) - tree_low_cst (min_index, 0)));
3965 /* Output any buffered-up bit-fields preceding this element. */
3966 if (byte_buffer_in_use)
3968 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
3969 total_bytes++;
3970 byte_buffer_in_use = 0;
3973 /* Advance to offset of this element.
3974 Note no alignment needed in an array, since that is guaranteed
3975 if each element has the proper size. */
3976 if ((field != 0 || index != 0) && pos != total_bytes)
3978 assemble_zeros (pos - total_bytes);
3979 total_bytes = pos;
3982 /* Find the alignment of this element. */
3983 align2 = min_align (align, BITS_PER_UNIT * pos);
3985 /* Determine size this element should occupy. */
3986 if (field)
3988 fieldsize = 0;
3990 /* If this is an array with an unspecified upper bound,
3991 the initializer determines the size. */
3992 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
3993 but we cannot do this until the deprecated support for
3994 initializing zero-length array members is removed. */
3995 if (TREE_CODE (TREE_TYPE (field)) == ARRAY_TYPE
3996 && TYPE_DOMAIN (TREE_TYPE (field))
3997 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (field))))
3999 fieldsize = array_size_for_constructor (val);
4000 /* Given a non-empty initialization, this field had
4001 better be last. */
4002 if (fieldsize != 0 && TREE_CHAIN (field) != NULL_TREE)
4003 abort ();
4005 else if (DECL_SIZE_UNIT (field))
4007 /* ??? This can't be right. If the decl size overflows
4008 a host integer we will silently emit no data. */
4009 if (host_integerp (DECL_SIZE_UNIT (field), 1))
4010 fieldsize = tree_low_cst (DECL_SIZE_UNIT (field), 1);
4013 else
4014 fieldsize = int_size_in_bytes (TREE_TYPE (type));
4016 /* Output the element's initial value. */
4017 if (val == 0)
4018 assemble_zeros (fieldsize);
4019 else
4020 output_constant (val, fieldsize, align2);
4022 /* Count its size. */
4023 total_bytes += fieldsize;
4025 else if (val != 0 && TREE_CODE (val) != INTEGER_CST)
4026 error ("invalid initial value for member %qs",
4027 IDENTIFIER_POINTER (DECL_NAME (field)));
4028 else
4030 /* Element that is a bit-field. */
4032 HOST_WIDE_INT next_offset = int_bit_position (field);
4033 HOST_WIDE_INT end_offset
4034 = (next_offset + tree_low_cst (DECL_SIZE (field), 1));
4036 if (val == 0)
4037 val = integer_zero_node;
4039 /* If this field does not start in this (or, next) byte,
4040 skip some bytes. */
4041 if (next_offset / BITS_PER_UNIT != total_bytes)
4043 /* Output remnant of any bit field in previous bytes. */
4044 if (byte_buffer_in_use)
4046 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4047 total_bytes++;
4048 byte_buffer_in_use = 0;
4051 /* If still not at proper byte, advance to there. */
4052 if (next_offset / BITS_PER_UNIT != total_bytes)
4054 assemble_zeros (next_offset / BITS_PER_UNIT - total_bytes);
4055 total_bytes = next_offset / BITS_PER_UNIT;
4059 if (! byte_buffer_in_use)
4060 byte = 0;
4062 /* We must split the element into pieces that fall within
4063 separate bytes, and combine each byte with previous or
4064 following bit-fields. */
4066 /* next_offset is the offset n fbits from the beginning of
4067 the structure to the next bit of this element to be processed.
4068 end_offset is the offset of the first bit past the end of
4069 this element. */
4070 while (next_offset < end_offset)
4072 int this_time;
4073 int shift;
4074 HOST_WIDE_INT value;
4075 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
4076 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
4078 /* Advance from byte to byte
4079 within this element when necessary. */
4080 while (next_byte != total_bytes)
4082 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4083 total_bytes++;
4084 byte = 0;
4087 /* Number of bits we can process at once
4088 (all part of the same byte). */
4089 this_time = MIN (end_offset - next_offset,
4090 BITS_PER_UNIT - next_bit);
4091 if (BYTES_BIG_ENDIAN)
4093 /* On big-endian machine, take the most significant bits
4094 first (of the bits that are significant)
4095 and put them into bytes from the most significant end. */
4096 shift = end_offset - next_offset - this_time;
4098 /* Don't try to take a bunch of bits that cross
4099 the word boundary in the INTEGER_CST. We can
4100 only select bits from the LOW or HIGH part
4101 not from both. */
4102 if (shift < HOST_BITS_PER_WIDE_INT
4103 && shift + this_time > HOST_BITS_PER_WIDE_INT)
4105 this_time = shift + this_time - HOST_BITS_PER_WIDE_INT;
4106 shift = HOST_BITS_PER_WIDE_INT;
4109 /* Now get the bits from the appropriate constant word. */
4110 if (shift < HOST_BITS_PER_WIDE_INT)
4111 value = TREE_INT_CST_LOW (val);
4112 else if (shift < 2 * HOST_BITS_PER_WIDE_INT)
4114 value = TREE_INT_CST_HIGH (val);
4115 shift -= HOST_BITS_PER_WIDE_INT;
4117 else
4118 abort ();
4120 /* Get the result. This works only when:
4121 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
4122 byte |= (((value >> shift)
4123 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
4124 << (BITS_PER_UNIT - this_time - next_bit));
4126 else
4128 /* On little-endian machines,
4129 take first the least significant bits of the value
4130 and pack them starting at the least significant
4131 bits of the bytes. */
4132 shift = next_offset - int_bit_position (field);
4134 /* Don't try to take a bunch of bits that cross
4135 the word boundary in the INTEGER_CST. We can
4136 only select bits from the LOW or HIGH part
4137 not from both. */
4138 if (shift < HOST_BITS_PER_WIDE_INT
4139 && shift + this_time > HOST_BITS_PER_WIDE_INT)
4140 this_time = (HOST_BITS_PER_WIDE_INT - shift);
4142 /* Now get the bits from the appropriate constant word. */
4143 if (shift < HOST_BITS_PER_WIDE_INT)
4144 value = TREE_INT_CST_LOW (val);
4145 else if (shift < 2 * HOST_BITS_PER_WIDE_INT)
4147 value = TREE_INT_CST_HIGH (val);
4148 shift -= HOST_BITS_PER_WIDE_INT;
4150 else
4151 abort ();
4153 /* Get the result. This works only when:
4154 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
4155 byte |= (((value >> shift)
4156 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
4157 << next_bit);
4160 next_offset += this_time;
4161 byte_buffer_in_use = 1;
4166 if (byte_buffer_in_use)
4168 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4169 total_bytes++;
4172 if ((unsigned HOST_WIDE_INT)total_bytes < size)
4173 assemble_zeros (size - total_bytes);
4176 /* This TREE_LIST contains any weak symbol declarations waiting
4177 to be emitted. */
4178 static GTY(()) tree weak_decls;
4180 /* Mark DECL as weak. */
4182 static void
4183 mark_weak (tree decl)
4185 DECL_WEAK (decl) = 1;
4187 if (DECL_RTL_SET_P (decl)
4188 && MEM_P (DECL_RTL (decl))
4189 && XEXP (DECL_RTL (decl), 0)
4190 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
4191 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
4194 /* Merge weak status between NEWDECL and OLDDECL. */
4196 void
4197 merge_weak (tree newdecl, tree olddecl)
4199 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
4200 return;
4202 if (DECL_WEAK (newdecl))
4204 tree wd;
4206 /* NEWDECL is weak, but OLDDECL is not. */
4208 /* If we already output the OLDDECL, we're in trouble; we can't
4209 go back and make it weak. This error cannot caught in
4210 declare_weak because the NEWDECL and OLDDECL was not yet
4211 been merged; therefore, TREE_ASM_WRITTEN was not set. */
4212 if (TREE_ASM_WRITTEN (olddecl))
4213 error ("%Jweak declaration of %qD must precede definition",
4214 newdecl, newdecl);
4216 /* If we've already generated rtl referencing OLDDECL, we may
4217 have done so in a way that will not function properly with
4218 a weak symbol. */
4219 else if (TREE_USED (olddecl)
4220 && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)))
4221 warning ("%Jweak declaration of %qD after first use results "
4222 "in unspecified behavior", newdecl, newdecl);
4224 if (SUPPORTS_WEAK)
4226 /* We put the NEWDECL on the weak_decls list at some point.
4227 Replace it with the OLDDECL. */
4228 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
4229 if (TREE_VALUE (wd) == newdecl)
4231 TREE_VALUE (wd) = olddecl;
4232 break;
4234 /* We may not find the entry on the list. If NEWDECL is a
4235 weak alias, then we will have already called
4236 globalize_decl to remove the entry; in that case, we do
4237 not need to do anything. */
4240 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
4241 mark_weak (olddecl);
4243 else
4244 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
4245 weak. Just update NEWDECL to indicate that it's weak too. */
4246 mark_weak (newdecl);
4249 /* Declare DECL to be a weak symbol. */
4251 void
4252 declare_weak (tree decl)
4254 if (! TREE_PUBLIC (decl))
4255 error ("%Jweak declaration of %qD must be public", decl, decl);
4256 else if (TREE_CODE (decl) == FUNCTION_DECL && TREE_ASM_WRITTEN (decl))
4257 error ("%Jweak declaration of %qD must precede definition", decl, decl);
4258 else if (SUPPORTS_WEAK)
4260 if (! DECL_WEAK (decl))
4261 weak_decls = tree_cons (NULL, decl, weak_decls);
4263 else
4264 warning ("%Jweak declaration of %qD not supported", decl, decl);
4266 mark_weak (decl);
4269 /* Emit any pending weak declarations. */
4271 void
4272 weak_finish (void)
4274 tree t;
4276 for (t = weak_decls; t; t = TREE_CHAIN (t))
4278 tree decl = TREE_VALUE (t);
4279 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
4280 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
4281 #endif
4283 if (! TREE_USED (decl))
4284 continue;
4286 #ifdef ASM_WEAKEN_DECL
4287 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
4288 #else
4289 #ifdef ASM_WEAKEN_LABEL
4290 ASM_WEAKEN_LABEL (asm_out_file, name);
4291 #else
4292 #ifdef ASM_OUTPUT_WEAK_ALIAS
4293 warning ("only weak aliases are supported in this configuration");
4294 return;
4295 #endif
4296 #endif
4297 #endif
4301 /* Emit the assembly bits to indicate that DECL is globally visible. */
4303 static void
4304 globalize_decl (tree decl)
4306 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
4308 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
4309 if (DECL_WEAK (decl))
4311 tree *p, t;
4313 #ifdef ASM_WEAKEN_DECL
4314 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
4315 #else
4316 ASM_WEAKEN_LABEL (asm_out_file, name);
4317 #endif
4319 /* Remove this function from the pending weak list so that
4320 we do not emit multiple .weak directives for it. */
4321 for (p = &weak_decls; (t = *p) ; )
4323 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
4324 *p = TREE_CHAIN (t);
4325 else
4326 p = &TREE_CHAIN (t);
4328 return;
4330 #elif defined(ASM_MAKE_LABEL_LINKONCE)
4331 if (DECL_ONE_ONLY (decl))
4332 ASM_MAKE_LABEL_LINKONCE (asm_out_file, name);
4333 #endif
4335 targetm.asm_out.globalize_label (asm_out_file, name);
4338 /* Emit an assembler directive to make the symbol for DECL an alias to
4339 the symbol for TARGET. */
4341 void
4342 assemble_alias (tree decl, tree target ATTRIBUTE_UNUSED)
4344 const char *name;
4346 /* We must force creation of DECL_RTL for debug info generation, even though
4347 we don't use it here. */
4348 make_decl_rtl (decl);
4350 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
4352 #ifdef ASM_OUTPUT_DEF
4353 /* Make name accessible from other files, if appropriate. */
4355 if (TREE_PUBLIC (decl))
4357 globalize_decl (decl);
4358 maybe_assemble_visibility (decl);
4361 #ifdef ASM_OUTPUT_DEF_FROM_DECLS
4362 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
4363 #else
4364 ASM_OUTPUT_DEF (asm_out_file, name, IDENTIFIER_POINTER (target));
4365 #endif
4366 #else /* !ASM_OUTPUT_DEF */
4367 #if defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
4368 if (DECL_WEAK (decl))
4370 tree *p, t;
4371 #ifdef ASM_WEAKEN_DECL
4372 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
4373 #else
4374 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
4375 #endif
4376 /* Remove this function from the pending weak list so that
4377 we do not emit multiple .weak directives for it. */
4378 for (p = &weak_decls; (t = *p) ; )
4379 if (DECL_ASSEMBLER_NAME (decl)
4380 == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
4381 *p = TREE_CHAIN (t);
4382 else
4383 p = &TREE_CHAIN (t);
4385 else
4386 warning ("only weak aliases are supported in this configuration");
4388 #else
4389 warning ("alias definitions not supported in this configuration; ignored");
4390 #endif
4391 #endif
4393 TREE_USED (decl) = 1;
4394 TREE_ASM_WRITTEN (decl) = 1;
4395 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
4398 /* Emit an assembler directive to set symbol for DECL visibility to
4399 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
4401 void
4402 default_assemble_visibility (tree decl, int vis)
4404 static const char * const visibility_types[] = {
4405 NULL, "internal", "hidden", "protected"
4408 const char *name, *type;
4410 name = (IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)));
4411 type = visibility_types[vis];
4413 #ifdef HAVE_GAS_HIDDEN
4414 fprintf (asm_out_file, "\t.%s\t", type);
4415 assemble_name (asm_out_file, name);
4416 fprintf (asm_out_file, "\n");
4417 #else
4418 warning ("visibility attribute not supported in this configuration; ignored");
4419 #endif
4422 /* A helper function to call assemble_visibility when needed for a decl. */
4424 static void
4425 maybe_assemble_visibility (tree decl)
4427 enum symbol_visibility vis = DECL_VISIBILITY (decl);
4429 if (vis != VISIBILITY_DEFAULT)
4430 targetm.asm_out.visibility (decl, vis);
4433 /* Returns 1 if the target configuration supports defining public symbols
4434 so that one of them will be chosen at link time instead of generating a
4435 multiply-defined symbol error, whether through the use of weak symbols or
4436 a target-specific mechanism for having duplicates discarded. */
4439 supports_one_only (void)
4441 if (SUPPORTS_ONE_ONLY)
4442 return 1;
4443 return SUPPORTS_WEAK;
4446 /* Set up DECL as a public symbol that can be defined in multiple
4447 translation units without generating a linker error. */
4449 void
4450 make_decl_one_only (tree decl)
4452 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != FUNCTION_DECL)
4453 abort ();
4455 TREE_PUBLIC (decl) = 1;
4457 if (SUPPORTS_ONE_ONLY)
4459 #ifdef MAKE_DECL_ONE_ONLY
4460 MAKE_DECL_ONE_ONLY (decl);
4461 #endif
4462 DECL_ONE_ONLY (decl) = 1;
4464 else if (TREE_CODE (decl) == VAR_DECL
4465 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node))
4466 DECL_COMMON (decl) = 1;
4467 else if (SUPPORTS_WEAK)
4468 DECL_WEAK (decl) = 1;
4469 else
4470 abort ();
4473 void
4474 init_varasm_once (void)
4476 in_named_htab = htab_create_ggc (31, in_named_entry_hash,
4477 in_named_entry_eq, NULL);
4478 const_desc_htab = htab_create_ggc (1009, const_desc_hash,
4479 const_desc_eq, NULL);
4481 const_alias_set = new_alias_set ();
4484 static enum tls_model
4485 decl_tls_model (tree decl)
4487 enum tls_model kind;
4488 tree attr = lookup_attribute ("tls_model", DECL_ATTRIBUTES (decl));
4489 bool is_local;
4491 if (attr)
4493 attr = TREE_VALUE (TREE_VALUE (attr));
4494 if (TREE_CODE (attr) != STRING_CST)
4495 abort ();
4496 if (!strcmp (TREE_STRING_POINTER (attr), "local-exec"))
4497 kind = TLS_MODEL_LOCAL_EXEC;
4498 else if (!strcmp (TREE_STRING_POINTER (attr), "initial-exec"))
4499 kind = TLS_MODEL_INITIAL_EXEC;
4500 else if (!strcmp (TREE_STRING_POINTER (attr), "local-dynamic"))
4501 kind = optimize ? TLS_MODEL_LOCAL_DYNAMIC : TLS_MODEL_GLOBAL_DYNAMIC;
4502 else if (!strcmp (TREE_STRING_POINTER (attr), "global-dynamic"))
4503 kind = TLS_MODEL_GLOBAL_DYNAMIC;
4504 else
4505 abort ();
4506 return kind;
4509 is_local = targetm.binds_local_p (decl);
4510 if (!flag_pic)
4512 if (is_local)
4513 kind = TLS_MODEL_LOCAL_EXEC;
4514 else
4515 kind = TLS_MODEL_INITIAL_EXEC;
4517 /* Local dynamic is inefficient when we're not combining the
4518 parts of the address. */
4519 else if (optimize && is_local)
4520 kind = TLS_MODEL_LOCAL_DYNAMIC;
4521 else
4522 kind = TLS_MODEL_GLOBAL_DYNAMIC;
4523 if (kind < flag_tls_default)
4524 kind = flag_tls_default;
4526 return kind;
4529 /* Select a set of attributes for section NAME based on the properties
4530 of DECL and whether or not RELOC indicates that DECL's initializer
4531 might contain runtime relocations.
4533 We make the section read-only and executable for a function decl,
4534 read-only for a const data decl, and writable for a non-const data decl. */
4536 unsigned int
4537 default_section_type_flags (tree decl, const char *name, int reloc)
4539 return default_section_type_flags_1 (decl, name, reloc, flag_pic);
4542 unsigned int
4543 default_section_type_flags_1 (tree decl, const char *name, int reloc,
4544 int shlib)
4546 unsigned int flags;
4548 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
4549 flags = SECTION_CODE;
4550 else if (decl && decl_readonly_section_1 (decl, reloc, shlib))
4551 flags = 0;
4552 else if (unlikely_text_section_name
4553 && strcmp (name, unlikely_text_section_name) == 0)
4554 flags = SECTION_CODE;
4555 else
4556 flags = SECTION_WRITE;
4558 if (decl && DECL_ONE_ONLY (decl))
4559 flags |= SECTION_LINKONCE;
4561 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl))
4562 flags |= SECTION_TLS | SECTION_WRITE;
4564 if (strcmp (name, ".bss") == 0
4565 || strncmp (name, ".bss.", 5) == 0
4566 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
4567 || strcmp (name, ".sbss") == 0
4568 || strncmp (name, ".sbss.", 6) == 0
4569 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0
4570 || strcmp (name, ".tbss") == 0
4571 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
4572 flags |= SECTION_BSS;
4574 if (strcmp (name, ".tdata") == 0
4575 || strcmp (name, ".tbss") == 0
4576 || strncmp (name, ".gnu.linkonce.td.", 17) == 0
4577 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
4578 flags |= SECTION_TLS;
4580 /* These three sections have special ELF types. They are neither
4581 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
4582 want to print a section type (@progbits or @nobits). If someone
4583 is silly enough to emit code or TLS variables to one of these
4584 sections, then don't handle them specially. */
4585 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
4586 && (strcmp (name, ".init_array") == 0
4587 || strcmp (name, ".fini_array") == 0
4588 || strcmp (name, ".preinit_array") == 0))
4589 flags |= SECTION_NOTYPE;
4591 return flags;
4594 /* Output assembly to switch to section NAME with attribute FLAGS.
4595 Four variants for common object file formats. */
4597 void
4598 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
4599 unsigned int flags ATTRIBUTE_UNUSED,
4600 tree decl ATTRIBUTE_UNUSED)
4602 /* Some object formats don't support named sections at all. The
4603 front-end should already have flagged this as an error. */
4604 abort ();
4607 void
4608 default_elf_asm_named_section (const char *name, unsigned int flags,
4609 tree decl ATTRIBUTE_UNUSED)
4611 char flagchars[10], *f = flagchars;
4613 /* If we have already declared this section, we can use an
4614 abbreviated form to switch back to it -- unless this section is
4615 part of a COMDAT groups, in which case GAS requires the full
4616 declaration every time. */
4617 if (!(HAVE_GAS_COMDAT_GROUP && (flags & SECTION_LINKONCE))
4618 && ! named_section_first_declaration (name))
4620 fprintf (asm_out_file, "\t.section\t%s\n", name);
4621 return;
4624 if (!(flags & SECTION_DEBUG))
4625 *f++ = 'a';
4626 if (flags & SECTION_WRITE)
4627 *f++ = 'w';
4628 if (flags & SECTION_CODE)
4629 *f++ = 'x';
4630 if (flags & SECTION_SMALL)
4631 *f++ = 's';
4632 if (flags & SECTION_MERGE)
4633 *f++ = 'M';
4634 if (flags & SECTION_STRINGS)
4635 *f++ = 'S';
4636 if (flags & SECTION_TLS)
4637 *f++ = 'T';
4638 if (HAVE_GAS_COMDAT_GROUP && (flags & SECTION_LINKONCE))
4639 *f++ = 'G';
4640 *f = '\0';
4642 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
4644 if (!(flags & SECTION_NOTYPE))
4646 const char *type;
4647 const char *format;
4649 if (flags & SECTION_BSS)
4650 type = "nobits";
4651 else
4652 type = "progbits";
4654 format = ",@%s";
4655 #ifdef ASM_COMMENT_START
4656 /* On platforms that use "@" as the assembly comment character,
4657 use "%" instead. */
4658 if (strcmp (ASM_COMMENT_START, "@") == 0)
4659 format = ",%%%s";
4660 #endif
4661 fprintf (asm_out_file, format, type);
4663 if (flags & SECTION_ENTSIZE)
4664 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
4665 if (HAVE_GAS_COMDAT_GROUP && (flags & SECTION_LINKONCE))
4666 fprintf (asm_out_file, ",%s,comdat",
4667 lang_hooks.decls.comdat_group (decl));
4670 putc ('\n', asm_out_file);
4673 void
4674 default_coff_asm_named_section (const char *name, unsigned int flags,
4675 tree decl ATTRIBUTE_UNUSED)
4677 char flagchars[8], *f = flagchars;
4679 if (flags & SECTION_WRITE)
4680 *f++ = 'w';
4681 if (flags & SECTION_CODE)
4682 *f++ = 'x';
4683 *f = '\0';
4685 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
4688 void
4689 default_pe_asm_named_section (const char *name, unsigned int flags,
4690 tree decl)
4692 default_coff_asm_named_section (name, flags, decl);
4694 if (flags & SECTION_LINKONCE)
4696 /* Functions may have been compiled at various levels of
4697 optimization so we can't use `same_size' here.
4698 Instead, have the linker pick one. */
4699 fprintf (asm_out_file, "\t.linkonce %s\n",
4700 (flags & SECTION_CODE ? "discard" : "same_size"));
4704 /* The lame default section selector. */
4706 void
4707 default_select_section (tree decl, int reloc,
4708 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
4710 bool readonly = false;
4712 if (DECL_P (decl))
4714 if (decl_readonly_section (decl, reloc))
4715 readonly = true;
4717 else if (TREE_CODE (decl) == CONSTRUCTOR)
4719 if (! ((flag_pic && reloc)
4720 || !TREE_READONLY (decl)
4721 || TREE_SIDE_EFFECTS (decl)
4722 || !TREE_CONSTANT (decl)))
4723 readonly = true;
4725 else if (TREE_CODE (decl) == STRING_CST)
4726 readonly = true;
4727 else if (! (flag_pic && reloc))
4728 readonly = true;
4730 if (readonly)
4731 readonly_data_section ();
4732 else
4733 data_section ();
4736 /* A helper function for default_elf_select_section and
4737 default_elf_unique_section. Categorizes the DECL. */
4739 enum section_category
4741 SECCAT_TEXT,
4743 SECCAT_RODATA,
4744 SECCAT_RODATA_MERGE_STR,
4745 SECCAT_RODATA_MERGE_STR_INIT,
4746 SECCAT_RODATA_MERGE_CONST,
4747 SECCAT_SRODATA,
4749 SECCAT_DATA,
4751 /* To optimize loading of shared programs, define following subsections
4752 of data section:
4753 _REL Contains data that has relocations, so they get grouped
4754 together and dynamic linker will visit fewer pages in memory.
4755 _RO Contains data that is otherwise read-only. This is useful
4756 with prelinking as most relocations won't be dynamically
4757 linked and thus stay read only.
4758 _LOCAL Marks data containing relocations only to local objects.
4759 These relocations will get fully resolved by prelinking. */
4760 SECCAT_DATA_REL,
4761 SECCAT_DATA_REL_LOCAL,
4762 SECCAT_DATA_REL_RO,
4763 SECCAT_DATA_REL_RO_LOCAL,
4765 SECCAT_SDATA,
4766 SECCAT_TDATA,
4768 SECCAT_BSS,
4769 SECCAT_SBSS,
4770 SECCAT_TBSS
4773 static enum section_category
4774 categorize_decl_for_section (tree, int, int);
4776 static enum section_category
4777 categorize_decl_for_section (tree decl, int reloc, int shlib)
4779 enum section_category ret;
4781 if (TREE_CODE (decl) == FUNCTION_DECL)
4782 return SECCAT_TEXT;
4783 else if (TREE_CODE (decl) == STRING_CST)
4785 if (flag_mudflap) /* or !flag_merge_constants */
4786 return SECCAT_RODATA;
4787 else
4788 return SECCAT_RODATA_MERGE_STR;
4790 else if (TREE_CODE (decl) == VAR_DECL)
4792 if (DECL_INITIAL (decl) == NULL
4793 || DECL_INITIAL (decl) == error_mark_node
4794 || (flag_zero_initialized_in_bss
4795 /* Leave constant zeroes in .rodata so they can be shared. */
4796 && !TREE_READONLY (decl)
4797 && initializer_zerop (DECL_INITIAL (decl))))
4798 ret = SECCAT_BSS;
4799 else if (! TREE_READONLY (decl)
4800 || TREE_SIDE_EFFECTS (decl)
4801 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
4803 if (shlib && (reloc & 2))
4804 ret = SECCAT_DATA_REL;
4805 else if (shlib && reloc)
4806 ret = SECCAT_DATA_REL_LOCAL;
4807 else
4808 ret = SECCAT_DATA;
4810 else if (shlib && (reloc & 2))
4811 ret = SECCAT_DATA_REL_RO;
4812 else if (shlib && reloc)
4813 ret = SECCAT_DATA_REL_RO_LOCAL;
4814 else if (reloc || flag_merge_constants < 2)
4815 /* C and C++ don't allow different variables to share the same
4816 location. -fmerge-all-constants allows even that (at the
4817 expense of not conforming). */
4818 ret = SECCAT_RODATA;
4819 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
4820 ret = SECCAT_RODATA_MERGE_STR_INIT;
4821 else
4822 ret = SECCAT_RODATA_MERGE_CONST;
4824 else if (TREE_CODE (decl) == CONSTRUCTOR)
4826 if ((shlib && reloc)
4827 || TREE_SIDE_EFFECTS (decl)
4828 || ! TREE_CONSTANT (decl))
4829 ret = SECCAT_DATA;
4830 else
4831 ret = SECCAT_RODATA;
4833 else
4834 ret = SECCAT_RODATA;
4836 /* There are no read-only thread-local sections. */
4837 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl))
4839 /* Note that this would be *just* SECCAT_BSS, except that there's
4840 no concept of a read-only thread-local-data section. */
4841 if (ret == SECCAT_BSS
4842 || (flag_zero_initialized_in_bss
4843 && initializer_zerop (DECL_INITIAL (decl))))
4844 ret = SECCAT_TBSS;
4845 else
4846 ret = SECCAT_TDATA;
4849 /* If the target uses small data sections, select it. */
4850 else if (targetm.in_small_data_p (decl))
4852 if (ret == SECCAT_BSS)
4853 ret = SECCAT_SBSS;
4854 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
4855 ret = SECCAT_SRODATA;
4856 else
4857 ret = SECCAT_SDATA;
4860 return ret;
4863 bool
4864 decl_readonly_section (tree decl, int reloc)
4866 return decl_readonly_section_1 (decl, reloc, flag_pic);
4869 bool
4870 decl_readonly_section_1 (tree decl, int reloc, int shlib)
4872 switch (categorize_decl_for_section (decl, reloc, shlib))
4874 case SECCAT_RODATA:
4875 case SECCAT_RODATA_MERGE_STR:
4876 case SECCAT_RODATA_MERGE_STR_INIT:
4877 case SECCAT_RODATA_MERGE_CONST:
4878 case SECCAT_SRODATA:
4879 return true;
4880 break;
4881 default:
4882 return false;
4883 break;
4887 /* Select a section based on the above categorization. */
4889 void
4890 default_elf_select_section (tree decl, int reloc,
4891 unsigned HOST_WIDE_INT align)
4893 default_elf_select_section_1 (decl, reloc, align, flag_pic);
4896 void
4897 default_elf_select_section_1 (tree decl, int reloc,
4898 unsigned HOST_WIDE_INT align, int shlib)
4900 switch (categorize_decl_for_section (decl, reloc, shlib))
4902 case SECCAT_TEXT:
4903 /* We're not supposed to be called on FUNCTION_DECLs. */
4904 abort ();
4905 case SECCAT_RODATA:
4906 readonly_data_section ();
4907 break;
4908 case SECCAT_RODATA_MERGE_STR:
4909 mergeable_string_section (decl, align, 0);
4910 break;
4911 case SECCAT_RODATA_MERGE_STR_INIT:
4912 mergeable_string_section (DECL_INITIAL (decl), align, 0);
4913 break;
4914 case SECCAT_RODATA_MERGE_CONST:
4915 mergeable_constant_section (DECL_MODE (decl), align, 0);
4916 break;
4917 case SECCAT_SRODATA:
4918 named_section (NULL_TREE, ".sdata2", reloc);
4919 break;
4920 case SECCAT_DATA:
4921 data_section ();
4922 break;
4923 case SECCAT_DATA_REL:
4924 named_section (NULL_TREE, ".data.rel", reloc);
4925 break;
4926 case SECCAT_DATA_REL_LOCAL:
4927 named_section (NULL_TREE, ".data.rel.local", reloc);
4928 break;
4929 case SECCAT_DATA_REL_RO:
4930 named_section (NULL_TREE, ".data.rel.ro", reloc);
4931 break;
4932 case SECCAT_DATA_REL_RO_LOCAL:
4933 named_section (NULL_TREE, ".data.rel.ro.local", reloc);
4934 break;
4935 case SECCAT_SDATA:
4936 named_section (NULL_TREE, ".sdata", reloc);
4937 break;
4938 case SECCAT_TDATA:
4939 named_section (NULL_TREE, ".tdata", reloc);
4940 break;
4941 case SECCAT_BSS:
4942 #ifdef BSS_SECTION_ASM_OP
4943 bss_section ();
4944 #else
4945 named_section (NULL_TREE, ".bss", reloc);
4946 #endif
4947 break;
4948 case SECCAT_SBSS:
4949 named_section (NULL_TREE, ".sbss", reloc);
4950 break;
4951 case SECCAT_TBSS:
4952 named_section (NULL_TREE, ".tbss", reloc);
4953 break;
4954 default:
4955 abort ();
4959 /* Construct a unique section name based on the decl name and the
4960 categorization performed above. */
4962 void
4963 default_unique_section (tree decl, int reloc)
4965 default_unique_section_1 (decl, reloc, flag_pic);
4968 void
4969 default_unique_section_1 (tree decl, int reloc, int shlib)
4971 bool one_only = DECL_ONE_ONLY (decl);
4972 const char *prefix, *name;
4973 size_t nlen, plen;
4974 char *string;
4976 switch (categorize_decl_for_section (decl, reloc, shlib))
4978 case SECCAT_TEXT:
4979 prefix = one_only ? ".gnu.linkonce.t." : ".text.";
4980 break;
4981 case SECCAT_RODATA:
4982 case SECCAT_RODATA_MERGE_STR:
4983 case SECCAT_RODATA_MERGE_STR_INIT:
4984 case SECCAT_RODATA_MERGE_CONST:
4985 prefix = one_only ? ".gnu.linkonce.r." : ".rodata.";
4986 break;
4987 case SECCAT_SRODATA:
4988 prefix = one_only ? ".gnu.linkonce.s2." : ".sdata2.";
4989 break;
4990 case SECCAT_DATA:
4991 case SECCAT_DATA_REL:
4992 case SECCAT_DATA_REL_LOCAL:
4993 case SECCAT_DATA_REL_RO:
4994 case SECCAT_DATA_REL_RO_LOCAL:
4995 prefix = one_only ? ".gnu.linkonce.d." : ".data.";
4996 break;
4997 case SECCAT_SDATA:
4998 prefix = one_only ? ".gnu.linkonce.s." : ".sdata.";
4999 break;
5000 case SECCAT_BSS:
5001 prefix = one_only ? ".gnu.linkonce.b." : ".bss.";
5002 break;
5003 case SECCAT_SBSS:
5004 prefix = one_only ? ".gnu.linkonce.sb." : ".sbss.";
5005 break;
5006 case SECCAT_TDATA:
5007 prefix = one_only ? ".gnu.linkonce.td." : ".tdata.";
5008 break;
5009 case SECCAT_TBSS:
5010 prefix = one_only ? ".gnu.linkonce.tb." : ".tbss.";
5011 break;
5012 default:
5013 abort ();
5015 plen = strlen (prefix);
5017 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5018 name = targetm.strip_name_encoding (name);
5019 nlen = strlen (name);
5021 string = alloca (nlen + plen + 1);
5022 memcpy (string, prefix, plen);
5023 memcpy (string + plen, name, nlen + 1);
5025 DECL_SECTION_NAME (decl) = build_string (nlen + plen, string);
5028 void
5029 default_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
5030 rtx x,
5031 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
5033 if (flag_pic)
5034 switch (GET_CODE (x))
5036 case CONST:
5037 case SYMBOL_REF:
5038 case LABEL_REF:
5039 data_section ();
5040 return;
5042 default:
5043 break;
5046 readonly_data_section ();
5049 void
5050 default_elf_select_rtx_section (enum machine_mode mode, rtx x,
5051 unsigned HOST_WIDE_INT align)
5053 /* ??? Handle small data here somehow. */
5055 if (flag_pic)
5056 switch (GET_CODE (x))
5058 case CONST:
5059 case SYMBOL_REF:
5060 named_section (NULL_TREE, ".data.rel.ro", 3);
5061 return;
5063 case LABEL_REF:
5064 named_section (NULL_TREE, ".data.rel.ro.local", 1);
5065 return;
5067 default:
5068 break;
5071 mergeable_constant_section (mode, align, 0);
5074 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
5076 void
5077 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
5079 rtx symbol;
5080 int flags;
5082 /* Careful not to prod global register variables. */
5083 if (!MEM_P (rtl))
5084 return;
5085 symbol = XEXP (rtl, 0);
5086 if (GET_CODE (symbol) != SYMBOL_REF)
5087 return;
5089 flags = 0;
5090 if (TREE_CODE (decl) == FUNCTION_DECL)
5091 flags |= SYMBOL_FLAG_FUNCTION;
5092 if (targetm.binds_local_p (decl))
5093 flags |= SYMBOL_FLAG_LOCAL;
5094 if (targetm.in_small_data_p (decl))
5095 flags |= SYMBOL_FLAG_SMALL;
5096 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl))
5097 flags |= decl_tls_model (decl) << SYMBOL_FLAG_TLS_SHIFT;
5098 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
5099 being PUBLIC, the thing *must* be defined in this translation unit.
5100 Prevent this buglet from being propagated into rtl code as well. */
5101 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
5102 flags |= SYMBOL_FLAG_EXTERNAL;
5104 SYMBOL_REF_FLAGS (symbol) = flags;
5107 /* By default, we do nothing for encode_section_info, so we need not
5108 do anything but discard the '*' marker. */
5110 const char *
5111 default_strip_name_encoding (const char *str)
5113 return str + (*str == '*');
5116 /* Assume ELF-ish defaults, since that's pretty much the most liberal
5117 wrt cross-module name binding. */
5119 bool
5120 default_binds_local_p (tree exp)
5122 return default_binds_local_p_1 (exp, flag_shlib);
5125 bool
5126 default_binds_local_p_1 (tree exp, int shlib)
5128 bool local_p;
5130 /* A non-decl is an entry in the constant pool. */
5131 if (!DECL_P (exp))
5132 local_p = true;
5133 /* Static variables are always local. */
5134 else if (! TREE_PUBLIC (exp))
5135 local_p = true;
5136 /* A variable is local if the user explicitly tells us so. */
5137 else if (DECL_VISIBILITY_SPECIFIED (exp) && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
5138 local_p = true;
5139 /* Otherwise, variables defined outside this object may not be local. */
5140 else if (DECL_EXTERNAL (exp))
5141 local_p = false;
5142 /* Linkonce and weak data are never local. */
5143 else if (DECL_ONE_ONLY (exp) || DECL_WEAK (exp))
5144 local_p = false;
5145 /* If none of the above and visibility is not default, make local. */
5146 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
5147 local_p = true;
5148 /* If PIC, then assume that any global name can be overridden by
5149 symbols resolved from other modules. */
5150 else if (shlib)
5151 local_p = false;
5152 /* Uninitialized COMMON variable may be unified with symbols
5153 resolved from other modules. */
5154 else if (DECL_COMMON (exp)
5155 && (DECL_INITIAL (exp) == NULL
5156 || DECL_INITIAL (exp) == error_mark_node))
5157 local_p = false;
5158 /* Otherwise we're left with initialized (or non-common) global data
5159 which is of necessity defined locally. */
5160 else
5161 local_p = true;
5163 return local_p;
5166 /* Determine whether or not a pointer mode is valid. Assume defaults
5167 of ptr_mode or Pmode - can be overridden. */
5168 bool
5169 default_valid_pointer_mode (enum machine_mode mode)
5171 return (mode == ptr_mode || mode == Pmode);
5174 /* Default function to output code that will globalize a label. A
5175 target must define GLOBAL_ASM_OP or provide it's own function to
5176 globalize a label. */
5177 #ifdef GLOBAL_ASM_OP
5178 void
5179 default_globalize_label (FILE * stream, const char *name)
5181 fputs (GLOBAL_ASM_OP, stream);
5182 assemble_name (stream, name);
5183 putc ('\n', stream);
5185 #endif /* GLOBAL_ASM_OP */
5187 /* Default function to output a label for unwind information. The
5188 default is to do nothing. A target that needs nonlocal labels for
5189 unwind information must provide its own function to do this. */
5190 void
5191 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
5192 tree decl ATTRIBUTE_UNUSED,
5193 int for_eh ATTRIBUTE_UNUSED,
5194 int empty ATTRIBUTE_UNUSED)
5198 /* This is how to output an internal numbered label where PREFIX is
5199 the class of label and LABELNO is the number within the class. */
5201 void
5202 default_internal_label (FILE *stream, const char *prefix,
5203 unsigned long labelno)
5205 char *const buf = alloca (40 + strlen (prefix));
5206 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
5207 ASM_OUTPUT_LABEL (stream, buf);
5210 /* This is the default behavior at the beginning of a file. It's
5211 controlled by two other target-hook toggles. */
5212 void
5213 default_file_start (void)
5215 if (targetm.file_start_app_off && !flag_verbose_asm)
5216 fputs (ASM_APP_OFF, asm_out_file);
5218 if (targetm.file_start_file_directive)
5219 output_file_directive (asm_out_file, main_input_filename);
5222 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
5223 which emits a special section directive used to indicate whether or
5224 not this object file needs an executable stack. This is primarily
5225 a GNU extension to ELF but could be used on other targets. */
5227 int trampolines_created;
5229 void
5230 file_end_indicate_exec_stack (void)
5232 unsigned int flags = SECTION_DEBUG;
5233 if (trampolines_created)
5234 flags |= SECTION_CODE;
5236 named_section_flags (".note.GNU-stack", flags);
5239 #include "gt-varasm.h"