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 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
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
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
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. */
37 #include "hard-reg-set.h"
46 #include "langhooks.h"
51 #ifdef XCOFF_DEBUGGING_INFO
52 #include "xcoffout.h" /* Needed for external data
53 declarations for e.g. AIX 4.x. */
56 #ifndef TRAMPOLINE_ALIGNMENT
57 #define TRAMPOLINE_ALIGNMENT FUNCTION_BOUNDARY
61 #define ASM_STABS_OP "\t.stabs\t"
64 /* The (assembler) name of the first globally-visible object output. */
65 const char *first_global_object_name;
66 const char *weak_global_object_name;
69 struct constant_descriptor_rtx;
73 #define MAX_RTX_HASH_TABLE 61
75 struct varasm_status GTY(())
77 /* Hash facility for making memory-constants
78 from constant rtl-expressions. It is used on RISC machines
79 where immediate integer arguments and constant addresses are restricted
80 so that such constants must be stored in memory.
82 This pool of constants is reinitialized for each function
83 so each function gets its own constants-pool that comes right before
85 struct constant_descriptor_rtx ** GTY ((length ("MAX_RTX_HASH_TABLE")))
86 x_const_rtx_hash_table;
87 struct pool_constant ** GTY ((length ("MAX_RTX_HASH_TABLE")))
88 x_const_rtx_sym_hash_table;
90 /* Pointers to first and last constant in pool. */
91 struct pool_constant *x_first_pool;
92 struct pool_constant *x_last_pool;
94 /* Current offset in constant pool (does not include any machine-specific
96 HOST_WIDE_INT x_pool_offset;
99 #define const_rtx_hash_table (cfun->varasm->x_const_rtx_hash_table)
100 #define const_rtx_sym_hash_table (cfun->varasm->x_const_rtx_sym_hash_table)
101 #define first_pool (cfun->varasm->x_first_pool)
102 #define last_pool (cfun->varasm->x_last_pool)
103 #define pool_offset (cfun->varasm->x_pool_offset)
105 /* Number for making the label on the next
106 constant that is stored in memory. */
110 /* Number for making the label on the next
111 static variable internal to a function. */
115 /* Carry information from ASM_DECLARE_OBJECT_NAME
116 to ASM_FINISH_DECLARE_OBJECT. */
118 int size_directive_output;
120 /* The last decl for which assemble_variable was called,
121 if it did ASM_DECLARE_OBJECT_NAME.
122 If the last call to assemble_variable didn't do that,
125 tree last_assemble_variable_decl;
127 /* RTX_UNCHANGING_P in a MEM can mean it is stored into, for initialization.
128 So giving constant the alias set for the type will allow such
129 initializations to appear to conflict with the load of the constant. We
130 avoid this by giving all constants an alias set for just constants.
131 Since there will be no stores to that alias set, nothing will ever
132 conflict with them. */
134 static HOST_WIDE_INT const_alias_set;
136 static const char *strip_reg_name PARAMS ((const char *));
137 static int contains_pointers_p PARAMS ((tree));
138 static void decode_addr_const PARAMS ((tree, struct addr_const *));
139 static int const_hash PARAMS ((tree));
140 static int compare_constant PARAMS ((tree, tree));
141 static tree copy_constant PARAMS ((tree));
142 static void output_constant_def_contents PARAMS ((tree, int, int));
143 static void decode_rtx_const PARAMS ((enum machine_mode, rtx,
144 struct rtx_const *));
145 static int const_hash_rtx PARAMS ((enum machine_mode, rtx));
146 static int compare_constant_rtx
147 PARAMS ((enum machine_mode, rtx, struct constant_descriptor_rtx *));
148 static struct constant_descriptor_rtx * record_constant_rtx
149 PARAMS ((enum machine_mode, rtx));
150 static struct pool_constant *find_pool_constant PARAMS ((struct function *, rtx));
151 static void mark_constant_pool PARAMS ((void));
152 static void mark_constants PARAMS ((rtx));
153 static int mark_constant PARAMS ((rtx *current_rtx, void *data));
154 static int output_addressed_constants PARAMS ((tree));
155 static void output_after_function_constants PARAMS ((void));
156 static unsigned HOST_WIDE_INT array_size_for_constructor PARAMS ((tree));
157 static unsigned min_align PARAMS ((unsigned, unsigned));
158 static void output_constructor PARAMS ((tree, HOST_WIDE_INT,
160 static void globalize_decl PARAMS ((tree));
161 static void maybe_assemble_visibility PARAMS ((tree));
162 static int in_named_entry_eq PARAMS ((const PTR, const PTR));
163 static hashval_t in_named_entry_hash PARAMS ((const PTR));
164 #ifdef ASM_OUTPUT_BSS
165 static void asm_output_bss PARAMS ((FILE *, tree, const char *, int, int));
167 #ifdef BSS_SECTION_ASM_OP
168 #ifdef ASM_OUTPUT_ALIGNED_BSS
169 static void asm_output_aligned_bss PARAMS ((FILE *, tree, const char *,
172 #endif /* BSS_SECTION_ASM_OP */
173 static hashval_t const_str_htab_hash PARAMS ((const void *x));
174 static int const_str_htab_eq PARAMS ((const void *x, const void *y));
175 static void asm_emit_uninitialised PARAMS ((tree, const char*, int, int));
176 static void resolve_unique_section PARAMS ((tree, int, int));
177 static void mark_weak PARAMS ((tree));
179 static enum in_section { no_section, in_text, in_data, in_named
180 #ifdef BSS_SECTION_ASM_OP
183 #ifdef CTORS_SECTION_ASM_OP
186 #ifdef DTORS_SECTION_ASM_OP
189 #ifdef READONLY_DATA_SECTION_ASM_OP
192 #ifdef EXTRA_SECTIONS
195 } in_section = no_section;
197 /* Return a non-zero value if DECL has a section attribute. */
198 #ifndef IN_NAMED_SECTION
199 #define IN_NAMED_SECTION(DECL) \
200 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \
201 && DECL_SECTION_NAME (DECL) != NULL_TREE)
204 /* Text of section name when in_section == in_named. */
205 static const char *in_named_name;
207 /* Hash table of flags that have been used for a particular named section. */
209 struct in_named_entry
216 static htab_t in_named_htab;
218 /* Define functions like text_section for any extra sections. */
219 #ifdef EXTRA_SECTION_FUNCTIONS
220 EXTRA_SECTION_FUNCTIONS
223 /* Tell assembler to switch to text section. */
228 if (in_section != in_text)
230 in_section = in_text;
234 fprintf (asm_out_file, "%s\n", TEXT_SECTION_ASM_OP);
239 /* Tell assembler to switch to data section. */
244 if (in_section != in_data)
246 in_section = in_data;
247 if (flag_shared_data)
249 #ifdef SHARED_SECTION_ASM_OP
250 fprintf (asm_out_file, "%s\n", SHARED_SECTION_ASM_OP);
252 fprintf (asm_out_file, "%s\n", DATA_SECTION_ASM_OP);
256 fprintf (asm_out_file, "%s\n", DATA_SECTION_ASM_OP);
260 /* Tell assembler to ALWAYS switch to data section, in case
261 it's not sure where it is. */
264 force_data_section ()
266 in_section = no_section;
270 /* Tell assembler to switch to read-only data section. This is normally
274 readonly_data_section ()
276 #ifdef READONLY_DATA_SECTION
277 READONLY_DATA_SECTION (); /* Note this can call data_section. */
279 #ifdef READONLY_DATA_SECTION_ASM_OP
280 if (in_section != in_readonly_data)
282 in_section = in_readonly_data;
283 fputs (READONLY_DATA_SECTION_ASM_OP, asm_out_file);
284 fputc ('\n', asm_out_file);
292 /* Determine if we're in the text section. */
297 return in_section == in_text;
300 /* Determine if we're in the data section. */
305 return in_section == in_data;
308 /* Helper routines for maintaining in_named_htab. */
311 in_named_entry_eq (p1, p2)
315 const struct in_named_entry *old = p1;
316 const char *new = p2;
318 return strcmp (old->name, new) == 0;
322 in_named_entry_hash (p)
325 const struct in_named_entry *old = p;
326 return htab_hash_string (old->name);
329 /* If SECTION has been seen before as a named section, return the flags
330 that were used. Otherwise, return 0. Note, that 0 is a perfectly valid
331 set of flags for a section to have, so 0 does not mean that the section
332 has not been seen. */
335 get_named_section_flags (section)
338 struct in_named_entry **slot;
340 slot = (struct in_named_entry **)
341 htab_find_slot_with_hash (in_named_htab, section,
342 htab_hash_string (section), NO_INSERT);
344 return slot ? (*slot)->flags : 0;
347 /* Returns true if the section has been declared before. Sets internal
348 flag on this section in in_named_hash so subsequent calls on this
349 section will return false. */
352 named_section_first_declaration (name)
355 struct in_named_entry **slot;
357 slot = (struct in_named_entry **)
358 htab_find_slot_with_hash (in_named_htab, name,
359 htab_hash_string (name), NO_INSERT);
360 if (! (*slot)->declared)
362 (*slot)->declared = true;
372 /* Record FLAGS for SECTION. If SECTION was previously recorded with a
373 different set of flags, return false. */
376 set_named_section_flags (section, flags)
380 struct in_named_entry **slot, *entry;
382 slot = (struct in_named_entry **)
383 htab_find_slot_with_hash (in_named_htab, section,
384 htab_hash_string (section), INSERT);
389 entry = (struct in_named_entry *) xmalloc (sizeof (*entry));
391 entry->name = ggc_strdup (section);
392 entry->flags = flags;
393 entry->declared = false;
395 else if (entry->flags != flags)
401 /* Tell assembler to change to section NAME with attributes FLAGS. */
404 named_section_flags (name, flags)
408 if (in_section != in_named || strcmp (name, in_named_name) != 0)
410 if (! set_named_section_flags (name, flags))
413 (*targetm.asm_out.named_section) (name, flags);
415 if (flags & SECTION_FORGET)
416 in_section = no_section;
419 in_named_name = ggc_strdup (name);
420 in_section = in_named;
425 /* Tell assembler to change to section NAME for DECL.
426 If DECL is NULL, just switch to section NAME.
427 If NAME is NULL, get the name from DECL.
428 If RELOC is 1, the initializer for DECL contains relocs. */
431 named_section (decl, name, reloc)
438 if (decl != NULL_TREE && !DECL_P (decl))
441 name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
443 flags = (* targetm.section_type_flags) (decl, name, reloc);
445 /* Sanity check user variables for flag changes. Non-user
446 section flag changes will abort in named_section_flags.
447 However, don't complain if SECTION_OVERRIDE is set.
448 We trust that the setter knows that it is safe to ignore
449 the default flags for this decl. */
450 if (decl && ! set_named_section_flags (name, flags))
452 flags = get_named_section_flags (name);
453 if ((flags & SECTION_OVERRIDE) == 0)
454 error_with_decl (decl, "%s causes a section type conflict");
457 named_section_flags (name, flags);
460 /* If required, set DECL_SECTION_NAME to a unique name. */
463 resolve_unique_section (decl, reloc, flag_function_or_data_sections)
465 int reloc ATTRIBUTE_UNUSED;
466 int flag_function_or_data_sections;
468 if (DECL_SECTION_NAME (decl) == NULL_TREE
469 && targetm.have_named_sections
470 && (flag_function_or_data_sections
471 || DECL_ONE_ONLY (decl)))
472 (*targetm.asm_out.unique_section) (decl, reloc);
475 #ifdef BSS_SECTION_ASM_OP
477 /* Tell the assembler to switch to the bss section. */
482 if (in_section != in_bss)
484 #ifdef SHARED_BSS_SECTION_ASM_OP
485 if (flag_shared_data)
486 fprintf (asm_out_file, "%s\n", SHARED_BSS_SECTION_ASM_OP);
489 fprintf (asm_out_file, "%s\n", BSS_SECTION_ASM_OP);
495 #ifdef ASM_OUTPUT_BSS
497 /* Utility function for ASM_OUTPUT_BSS for targets to use if
498 they don't support alignments in .bss.
499 ??? It is believed that this function will work in most cases so such
500 support is localized here. */
503 asm_output_bss (file, decl, name, size, rounded)
505 tree decl ATTRIBUTE_UNUSED;
507 int size ATTRIBUTE_UNUSED, rounded;
509 ASM_GLOBALIZE_LABEL (file, name);
511 #ifdef ASM_DECLARE_OBJECT_NAME
512 last_assemble_variable_decl = decl;
513 ASM_DECLARE_OBJECT_NAME (file, name, decl);
515 /* Standard thing is just output label for the object. */
516 ASM_OUTPUT_LABEL (file, name);
517 #endif /* ASM_DECLARE_OBJECT_NAME */
518 ASM_OUTPUT_SKIP (file, rounded ? rounded : 1);
523 #ifdef ASM_OUTPUT_ALIGNED_BSS
525 /* Utility function for targets to use in implementing
526 ASM_OUTPUT_ALIGNED_BSS.
527 ??? It is believed that this function will work in most cases so such
528 support is localized here. */
531 asm_output_aligned_bss (file, decl, name, size, align)
533 tree decl ATTRIBUTE_UNUSED;
537 ASM_GLOBALIZE_LABEL (file, name);
539 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
540 #ifdef ASM_DECLARE_OBJECT_NAME
541 last_assemble_variable_decl = decl;
542 ASM_DECLARE_OBJECT_NAME (file, name, decl);
544 /* Standard thing is just output label for the object. */
545 ASM_OUTPUT_LABEL (file, name);
546 #endif /* ASM_DECLARE_OBJECT_NAME */
547 ASM_OUTPUT_SKIP (file, size ? size : 1);
552 #endif /* BSS_SECTION_ASM_OP */
554 /* Switch to the section for function DECL.
556 If DECL is NULL_TREE, switch to the text section.
557 ??? It's not clear that we will ever be passed NULL_TREE, but it's
558 safer to handle it. */
561 function_section (decl)
564 if (decl != NULL_TREE
565 && DECL_SECTION_NAME (decl) != NULL_TREE)
566 named_section (decl, (char *) 0, 0);
571 /* Switch to section for variable DECL. RELOC is the same as the
572 argument to SELECT_SECTION. */
575 variable_section (decl, reloc)
579 if (IN_NAMED_SECTION (decl))
580 named_section (decl, NULL, reloc);
582 (*targetm.asm_out.select_section) (decl, reloc, DECL_ALIGN (decl));
585 /* Tell assembler to switch to the section for the exception handling
589 default_exception_section ()
591 if (targetm.have_named_sections)
592 named_section (NULL_TREE, ".gcc_except_table", 0);
596 readonly_data_section ();
599 /* Tell assembler to switch to the section for string merging. */
602 mergeable_string_section (decl, align, flags)
603 tree decl ATTRIBUTE_UNUSED;
604 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED;
605 unsigned int flags ATTRIBUTE_UNUSED;
607 #ifdef HAVE_GAS_SHF_MERGE
608 if (flag_merge_constants
609 && TREE_CODE (decl) == STRING_CST
610 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
612 && TREE_STRING_LENGTH (decl) >= int_size_in_bytes (TREE_TYPE (decl)))
614 enum machine_mode mode;
615 unsigned int modesize;
620 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
621 modesize = GET_MODE_BITSIZE (mode);
622 if (modesize >= 8 && modesize <= 256
623 && (modesize & (modesize - 1)) == 0)
625 if (align < modesize)
628 str = TREE_STRING_POINTER (decl);
629 len = TREE_STRING_LENGTH (decl);
630 unit = GET_MODE_SIZE (mode);
632 /* Check for embedded NUL characters. */
633 for (i = 0; i < len; i += unit)
635 for (j = 0; j < unit; j++)
636 if (str[i + j] != '\0')
643 sprintf (name, ".rodata.str%d.%d", modesize / 8,
645 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
646 if (!i && modesize < align)
648 /* A "" string with requested alignment greater than
649 character size might cause a problem:
650 if some other string required even bigger
651 alignment than "", then linker might think the
652 "" is just part of padding after some other string
653 and not put it into the hash table initially.
654 But this means "" could have smaller alignment
656 #ifdef ASM_OUTPUT_SECTION_START
657 named_section_flags (name, flags);
658 ASM_OUTPUT_SECTION_START (asm_out_file);
660 readonly_data_section ();
665 named_section_flags (name, flags);
671 readonly_data_section ();
674 /* Tell assembler to switch to the section for constant merging. */
677 mergeable_constant_section (mode, align, flags)
678 enum machine_mode mode ATTRIBUTE_UNUSED;
679 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED;
680 unsigned int flags ATTRIBUTE_UNUSED;
682 #ifdef HAVE_GAS_SHF_MERGE
683 unsigned int modesize = GET_MODE_BITSIZE (mode);
685 if (flag_merge_constants
691 && (align & (align - 1)) == 0)
695 sprintf (name, ".rodata.cst%d", (int) (align / 8));
696 flags |= (align / 8) | SECTION_MERGE;
697 named_section_flags (name, flags);
701 readonly_data_section ();
704 /* Given NAME, a putative register name, discard any customary prefixes. */
707 strip_reg_name (name)
710 #ifdef REGISTER_PREFIX
711 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
712 name += strlen (REGISTER_PREFIX);
714 if (name[0] == '%' || name[0] == '#')
719 /* Decode an `asm' spec for a declaration as a register name.
720 Return the register number, or -1 if nothing specified,
721 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
722 or -3 if ASMSPEC is `cc' and is not recognized,
723 or -4 if ASMSPEC is `memory' and is not recognized.
724 Accept an exact spelling or a decimal number.
725 Prefixes such as % are optional. */
728 decode_reg_name (asmspec)
735 /* Get rid of confusing prefixes. */
736 asmspec = strip_reg_name (asmspec);
738 /* Allow a decimal number as a "register name". */
739 for (i = strlen (asmspec) - 1; i >= 0; i--)
740 if (! ISDIGIT (asmspec[i]))
742 if (asmspec[0] != 0 && i < 0)
745 if (i < FIRST_PSEUDO_REGISTER && i >= 0)
751 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
753 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
756 #ifdef ADDITIONAL_REGISTER_NAMES
758 static const struct { const char *const name; const int number; } table[]
759 = ADDITIONAL_REGISTER_NAMES;
761 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
762 if (! strcmp (asmspec, table[i].name))
763 return table[i].number;
765 #endif /* ADDITIONAL_REGISTER_NAMES */
767 if (!strcmp (asmspec, "memory"))
770 if (!strcmp (asmspec, "cc"))
779 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
780 have static storage duration. In other words, it should not be an
781 automatic variable, including PARM_DECLs.
783 There is, however, one exception: this function handles variables
784 explicitly placed in a particular register by the user.
786 ASMSPEC, if not 0, is the string which the user specified as the
787 assembler symbol name.
789 This is never called for PARM_DECL nodes. */
792 make_decl_rtl (decl, asmspec)
796 int top_level = (DECL_CONTEXT (decl) == NULL_TREE);
797 const char *name = 0;
798 const char *new_name = 0;
802 /* Check that we are not being given an automatic variable. */
803 /* A weak alias has TREE_PUBLIC set but not the other bits. */
804 if (TREE_CODE (decl) == PARM_DECL
805 || TREE_CODE (decl) == RESULT_DECL
806 || (TREE_CODE (decl) == VAR_DECL
807 && !TREE_STATIC (decl)
808 && !TREE_PUBLIC (decl)
809 && !DECL_EXTERNAL (decl)
810 && !DECL_REGISTER (decl)))
812 /* And that we were not given a type or a label. */
813 else if (TREE_CODE (decl) == TYPE_DECL
814 || TREE_CODE (decl) == LABEL_DECL)
817 /* For a duplicate declaration, we can be called twice on the
818 same DECL node. Don't discard the RTL already made. */
819 if (DECL_RTL_SET_P (decl))
821 /* If the old RTL had the wrong mode, fix the mode. */
822 if (GET_MODE (DECL_RTL (decl)) != DECL_MODE (decl))
823 SET_DECL_RTL (decl, adjust_address_nv (DECL_RTL (decl),
824 DECL_MODE (decl), 0));
826 /* ??? Another way to do this would be to maintain a hashed
827 table of such critters. Instead of adding stuff to a DECL
828 to give certain attributes to it, we could use an external
829 hash map from DECL to set of attributes. */
831 /* Let the target reassign the RTL if it wants.
832 This is necessary, for example, when one machine specific
833 decl attribute overrides another. */
834 (* targetm.encode_section_info) (decl, false);
838 new_name = name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
840 reg_number = decode_reg_name (asmspec);
841 if (reg_number == -2)
843 /* ASMSPEC is given, and not the name of a register. Mark the
844 name with a star so assemble_name won't munge it. */
845 char *starred = alloca (strlen (asmspec) + 2);
847 strcpy (starred + 1, asmspec);
851 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
853 /* First detect errors in declaring global registers. */
854 if (reg_number == -1)
855 error_with_decl (decl, "register name not specified for `%s'");
856 else if (reg_number < 0)
857 error_with_decl (decl, "invalid register name for `%s'");
858 else if (TYPE_MODE (TREE_TYPE (decl)) == BLKmode)
859 error_with_decl (decl,
860 "data type of `%s' isn't suitable for a register");
861 else if (! HARD_REGNO_MODE_OK (reg_number, TYPE_MODE (TREE_TYPE (decl))))
862 error_with_decl (decl,
863 "register specified for `%s' isn't suitable for data type");
864 /* Now handle properly declared static register variables. */
869 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
871 DECL_INITIAL (decl) = 0;
872 error ("global register variable has initial value");
874 if (TREE_THIS_VOLATILE (decl))
875 warning ("volatile register variables don't work as you might wish");
877 /* If the user specified one of the eliminables registers here,
878 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
879 confused with that register and be eliminated. This usage is
880 somewhat suspect... */
882 SET_DECL_RTL (decl, gen_rtx_raw_REG (DECL_MODE (decl), reg_number));
883 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
884 REG_USERVAR_P (DECL_RTL (decl)) = 1;
886 if (TREE_STATIC (decl))
888 /* Make this register global, so not usable for anything
890 #ifdef ASM_DECLARE_REGISTER_GLOBAL
891 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
893 nregs = HARD_REGNO_NREGS (reg_number, DECL_MODE (decl));
895 globalize_reg (reg_number + --nregs);
898 /* As a register variable, it has no section. */
903 /* Now handle ordinary static variables and functions (in memory).
904 Also handle vars declared register invalidly. */
906 if (reg_number >= 0 || reg_number == -3)
907 error_with_decl (decl,
908 "register name given for non-register variable `%s'");
910 /* Specifying a section attribute on a variable forces it into a
911 non-.bss section, and thus it cannot be common. */
912 if (TREE_CODE (decl) == VAR_DECL
913 && DECL_SECTION_NAME (decl) != NULL_TREE
914 && DECL_INITIAL (decl) == NULL_TREE
915 && DECL_COMMON (decl))
916 DECL_COMMON (decl) = 0;
918 /* Variables can't be both common and weak. */
919 if (TREE_CODE (decl) == VAR_DECL && DECL_WEAK (decl))
920 DECL_COMMON (decl) = 0;
922 /* Can't use just the variable's own name for a variable
923 whose scope is less than the whole file, unless it's a member
924 of a local class (which will already be unambiguous).
925 Concatenate a distinguishing number. */
926 if (!top_level && !TREE_PUBLIC (decl)
927 && ! (DECL_CONTEXT (decl) && TYPE_P (DECL_CONTEXT (decl)))
929 && name == IDENTIFIER_POINTER (DECL_NAME (decl)))
933 ASM_FORMAT_PRIVATE_NAME (label, name, var_labelno);
938 if (name != new_name)
940 SET_DECL_ASSEMBLER_NAME (decl, get_identifier (new_name));
941 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
944 /* If this variable is to be treated as volatile, show its
945 tree node has side effects. */
946 if ((flag_volatile_global && TREE_CODE (decl) == VAR_DECL
947 && TREE_PUBLIC (decl))
948 || ((flag_volatile_static && TREE_CODE (decl) == VAR_DECL
949 && (TREE_PUBLIC (decl) || TREE_STATIC (decl)))))
950 TREE_SIDE_EFFECTS (decl) = 1;
952 x = gen_rtx_MEM (DECL_MODE (decl), gen_rtx_SYMBOL_REF (Pmode, name));
953 SYMBOL_REF_WEAK (XEXP (x, 0)) = DECL_WEAK (decl);
954 if (TREE_CODE (decl) != FUNCTION_DECL)
955 set_mem_attributes (x, decl, 1);
956 SET_DECL_RTL (decl, x);
958 /* Optionally set flags or add text to the name to record information
959 such as that it is a function name.
960 If the name is changed, the macro ASM_OUTPUT_LABELREF
961 will have to know how to strip this information. */
962 (* targetm.encode_section_info) (decl, true);
965 /* Make the rtl for variable VAR be volatile.
966 Use this only for static variables. */
969 make_var_volatile (var)
972 if (GET_CODE (DECL_RTL (var)) != MEM)
975 MEM_VOLATILE_P (DECL_RTL (var)) = 1;
978 /* Output alignment directive to align for constant expression EXP. */
981 assemble_constant_align (exp)
986 /* Align the location counter as required by EXP's data type. */
987 align = TYPE_ALIGN (TREE_TYPE (exp));
988 #ifdef CONSTANT_ALIGNMENT
989 align = CONSTANT_ALIGNMENT (exp, align);
992 if (align > BITS_PER_UNIT)
994 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
998 /* Output a string of literal assembler code
999 for an `asm' keyword used between functions. */
1002 assemble_asm (string)
1007 if (TREE_CODE (string) == ADDR_EXPR)
1008 string = TREE_OPERAND (string, 0);
1010 fprintf (asm_out_file, "\t%s\n", TREE_STRING_POINTER (string));
1013 /* Record an element in the table of global destructors. SYMBOL is
1014 a SYMBOL_REF of the function to be called; PRIORITY is a number
1015 between 0 and MAX_INIT_PRIORITY. */
1018 default_stabs_asm_out_destructor (symbol, priority)
1020 int priority ATTRIBUTE_UNUSED;
1022 /* Tell GNU LD that this is part of the static destructor set.
1023 This will work for any system that uses stabs, most usefully
1025 fprintf (asm_out_file, "%s\"___DTOR_LIST__\",22,0,0,", ASM_STABS_OP);
1026 assemble_name (asm_out_file, XSTR (symbol, 0));
1027 fputc ('\n', asm_out_file);
1031 default_named_section_asm_out_destructor (symbol, priority)
1035 const char *section = ".dtors";
1038 /* ??? This only works reliably with the GNU linker. */
1039 if (priority != DEFAULT_INIT_PRIORITY)
1041 sprintf (buf, ".dtors.%.5u",
1042 /* Invert the numbering so the linker puts us in the proper
1043 order; constructors are run from right to left, and the
1044 linker sorts in increasing order. */
1045 MAX_INIT_PRIORITY - priority);
1049 named_section_flags (section, SECTION_WRITE);
1050 assemble_align (POINTER_SIZE);
1051 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1054 #ifdef DTORS_SECTION_ASM_OP
1058 if (in_section != in_dtors)
1060 in_section = in_dtors;
1061 fputs (DTORS_SECTION_ASM_OP, asm_out_file);
1062 fputc ('\n', asm_out_file);
1067 default_dtor_section_asm_out_destructor (symbol, priority)
1069 int priority ATTRIBUTE_UNUSED;
1072 assemble_align (POINTER_SIZE);
1073 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1077 /* Likewise for global constructors. */
1080 default_stabs_asm_out_constructor (symbol, priority)
1082 int priority ATTRIBUTE_UNUSED;
1084 /* Tell GNU LD that this is part of the static destructor set.
1085 This will work for any system that uses stabs, most usefully
1087 fprintf (asm_out_file, "%s\"___CTOR_LIST__\",22,0,0,", ASM_STABS_OP);
1088 assemble_name (asm_out_file, XSTR (symbol, 0));
1089 fputc ('\n', asm_out_file);
1093 default_named_section_asm_out_constructor (symbol, priority)
1097 const char *section = ".ctors";
1100 /* ??? This only works reliably with the GNU linker. */
1101 if (priority != DEFAULT_INIT_PRIORITY)
1103 sprintf (buf, ".ctors.%.5u",
1104 /* Invert the numbering so the linker puts us in the proper
1105 order; constructors are run from right to left, and the
1106 linker sorts in increasing order. */
1107 MAX_INIT_PRIORITY - priority);
1111 named_section_flags (section, SECTION_WRITE);
1112 assemble_align (POINTER_SIZE);
1113 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1116 #ifdef CTORS_SECTION_ASM_OP
1120 if (in_section != in_ctors)
1122 in_section = in_ctors;
1123 fputs (CTORS_SECTION_ASM_OP, asm_out_file);
1124 fputc ('\n', asm_out_file);
1129 default_ctor_section_asm_out_constructor (symbol, priority)
1131 int priority ATTRIBUTE_UNUSED;
1134 assemble_align (POINTER_SIZE);
1135 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1139 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1140 a non-zero value if the constant pool should be output before the
1141 start of the function, or a zero value if the pool should output
1142 after the end of the function. The default is to put it before the
1145 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1146 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1149 /* Output assembler code for the constant pool of a function and associated
1150 with defining the name of the function. DECL describes the function.
1151 NAME is the function's name. For the constant pool, we use the current
1152 constant pool data. */
1155 assemble_start_function (decl, fnname)
1161 /* The following code does not need preprocessing in the assembler. */
1165 if (CONSTANT_POOL_BEFORE_FUNCTION)
1166 output_constant_pool (fnname, decl);
1168 resolve_unique_section (decl, 0, flag_function_sections);
1169 function_section (decl);
1171 /* Tell assembler to move to target machine's alignment for functions. */
1172 align = floor_log2 (FUNCTION_BOUNDARY / BITS_PER_UNIT);
1175 ASM_OUTPUT_ALIGN (asm_out_file, align);
1178 /* Handle a user-specified function alignment.
1179 Note that we still need to align to FUNCTION_BOUNDARY, as above,
1180 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1181 if (align_functions_log > align
1182 && cfun->function_frequency != FUNCTION_FREQUENCY_UNLIKELY_EXECUTED)
1184 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1185 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1186 align_functions_log, align_functions - 1);
1188 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1192 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1193 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1196 (*debug_hooks->begin_function) (decl);
1198 /* Make function name accessible from other files, if appropriate. */
1200 if (TREE_PUBLIC (decl))
1202 if (! first_global_object_name)
1207 p = (* targetm.strip_name_encoding) (fnname);
1208 name = permalloc (strlen (p) + 1);
1211 if (! DECL_WEAK (decl) && ! DECL_ONE_ONLY (decl))
1212 first_global_object_name = name;
1214 weak_global_object_name = name;
1217 globalize_decl (decl);
1219 maybe_assemble_visibility (decl);
1222 /* Do any machine/system dependent processing of the function name */
1223 #ifdef ASM_DECLARE_FUNCTION_NAME
1224 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1226 /* Standard thing is just output label for the function. */
1227 ASM_OUTPUT_LABEL (asm_out_file, fnname);
1228 #endif /* ASM_DECLARE_FUNCTION_NAME */
1231 /* Output assembler code associated with defining the size of the
1232 function. DECL describes the function. NAME is the function's name. */
1235 assemble_end_function (decl, fnname)
1239 #ifdef ASM_DECLARE_FUNCTION_SIZE
1240 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1242 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1244 output_constant_pool (fnname, decl);
1245 function_section (decl); /* need to switch back */
1248 /* Output any constants which should appear after the function. */
1249 output_after_function_constants ();
1252 /* Assemble code to leave SIZE bytes of zeros. */
1255 assemble_zeros (size)
1258 /* Do no output if -fsyntax-only. */
1259 if (flag_syntax_only)
1262 #ifdef ASM_NO_SKIP_IN_TEXT
1263 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1264 so we must output 0s explicitly in the text section. */
1265 if (ASM_NO_SKIP_IN_TEXT && in_text_section ())
1268 for (i = 0; i < size; i++)
1269 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1274 ASM_OUTPUT_SKIP (asm_out_file, size);
1277 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1280 assemble_align (align)
1283 if (align > BITS_PER_UNIT)
1285 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1289 /* Assemble a string constant with the specified C string as contents. */
1292 assemble_string (p, size)
1299 /* If the string is very long, split it up. */
1303 int thissize = size - pos;
1304 if (thissize > maximum)
1307 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1315 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1316 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1317 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1319 #if defined ASM_OUTPUT_ALIGNED_LOCAL
1320 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1321 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, DECL_ALIGN (decl))
1323 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1324 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded)
1328 #if defined ASM_OUTPUT_ALIGNED_BSS
1329 #define ASM_EMIT_BSS(decl, name, size, rounded) \
1330 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1332 #if defined ASM_OUTPUT_BSS
1333 #define ASM_EMIT_BSS(decl, name, size, rounded) \
1334 ASM_OUTPUT_BSS (asm_out_file, decl, name, size, rounded)
1340 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1341 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1342 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1344 #if defined ASM_OUTPUT_ALIGNED_COMMON
1345 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1346 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size, DECL_ALIGN (decl))
1348 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1349 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded)
1354 asm_emit_uninitialised (decl, name, size, rounded)
1357 int size ATTRIBUTE_UNUSED;
1358 int rounded ATTRIBUTE_UNUSED;
1366 destination = asm_dest_local;
1368 if (TREE_PUBLIC (decl))
1370 #if defined ASM_EMIT_BSS
1371 if (! DECL_COMMON (decl))
1372 destination = asm_dest_bss;
1375 destination = asm_dest_common;
1378 if (destination == asm_dest_bss)
1379 globalize_decl (decl);
1380 resolve_unique_section (decl, 0, flag_data_sections);
1382 if (flag_shared_data)
1384 switch (destination)
1386 #ifdef ASM_OUTPUT_SHARED_BSS
1388 ASM_OUTPUT_SHARED_BSS (asm_out_file, decl, name, size, rounded);
1391 #ifdef ASM_OUTPUT_SHARED_COMMON
1392 case asm_dest_common:
1393 ASM_OUTPUT_SHARED_COMMON (asm_out_file, name, size, rounded);
1396 #ifdef ASM_OUTPUT_SHARED_LOCAL
1397 case asm_dest_local:
1398 ASM_OUTPUT_SHARED_LOCAL (asm_out_file, name, size, rounded);
1406 switch (destination)
1410 ASM_EMIT_BSS (decl, name, size, rounded);
1413 case asm_dest_common:
1414 ASM_EMIT_COMMON (decl, name, size, rounded);
1416 case asm_dest_local:
1417 ASM_EMIT_LOCAL (decl, name, size, rounded);
1426 /* Assemble everything that is needed for a variable or function declaration.
1427 Not used for automatic variables, and not used for function definitions.
1428 Should not be called for variables of incomplete structure type.
1430 TOP_LEVEL is nonzero if this variable has file scope.
1431 AT_END is nonzero if this is the special handling, at end of compilation,
1432 to define things that have had only tentative definitions.
1433 DONT_OUTPUT_DATA if nonzero means don't actually output the
1434 initial value (that will be done by the caller). */
1437 assemble_variable (decl, top_level, at_end, dont_output_data)
1439 int top_level ATTRIBUTE_UNUSED;
1440 int at_end ATTRIBUTE_UNUSED;
1441 int dont_output_data;
1448 last_assemble_variable_decl = 0;
1450 /* Normally no need to say anything here for external references,
1451 since assemble_external is called by the language-specific code
1452 when a declaration is first seen. */
1454 if (DECL_EXTERNAL (decl))
1457 /* Output no assembler code for a function declaration.
1458 Only definitions of functions output anything. */
1460 if (TREE_CODE (decl) == FUNCTION_DECL)
1463 /* Do nothing for global register variables. */
1464 if (DECL_RTL_SET_P (decl) && GET_CODE (DECL_RTL (decl)) == REG)
1466 TREE_ASM_WRITTEN (decl) = 1;
1470 /* If type was incomplete when the variable was declared,
1471 see if it is complete now. */
1473 if (DECL_SIZE (decl) == 0)
1474 layout_decl (decl, 0);
1476 /* Still incomplete => don't allocate it; treat the tentative defn
1477 (which is what it must have been) as an `extern' reference. */
1479 if (!dont_output_data && DECL_SIZE (decl) == 0)
1481 error_with_file_and_line (DECL_SOURCE_FILE (decl),
1482 DECL_SOURCE_LINE (decl),
1483 "storage size of `%s' isn't known",
1484 IDENTIFIER_POINTER (DECL_NAME (decl)));
1485 TREE_ASM_WRITTEN (decl) = 1;
1489 /* The first declaration of a variable that comes through this function
1490 decides whether it is global (in C, has external linkage)
1491 or local (in C, has internal linkage). So do nothing more
1492 if this function has already run. */
1494 if (TREE_ASM_WRITTEN (decl))
1497 /* Make sure targetm.encode_section_info is invoked before we set
1499 decl_rtl = DECL_RTL (decl);
1501 TREE_ASM_WRITTEN (decl) = 1;
1503 /* Do no output if -fsyntax-only. */
1504 if (flag_syntax_only)
1509 if (! dont_output_data
1510 && ! host_integerp (DECL_SIZE_UNIT (decl), 1))
1512 error_with_decl (decl, "size of variable `%s' is too large");
1516 name = XSTR (XEXP (decl_rtl, 0), 0);
1517 if (TREE_PUBLIC (decl) && DECL_NAME (decl)
1518 && ! first_global_object_name
1519 && ! (DECL_COMMON (decl) && (DECL_INITIAL (decl) == 0
1520 || DECL_INITIAL (decl) == error_mark_node))
1521 && ! DECL_WEAK (decl)
1522 && ! DECL_ONE_ONLY (decl))
1527 p = (* targetm.strip_name_encoding) (name);
1528 xname = permalloc (strlen (p) + 1);
1530 first_global_object_name = xname;
1533 /* Compute the alignment of this data. */
1535 align = DECL_ALIGN (decl);
1537 /* In the case for initialing an array whose length isn't specified,
1538 where we have not yet been able to do the layout,
1539 figure out the proper alignment now. */
1540 if (dont_output_data && DECL_SIZE (decl) == 0
1541 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
1542 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
1544 /* Some object file formats have a maximum alignment which they support.
1545 In particular, a.out format supports a maximum alignment of 4. */
1546 #ifndef MAX_OFILE_ALIGNMENT
1547 #define MAX_OFILE_ALIGNMENT BIGGEST_ALIGNMENT
1549 if (align > MAX_OFILE_ALIGNMENT)
1551 warning_with_decl (decl,
1552 "alignment of `%s' is greater than maximum object file alignment. Using %d",
1553 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
1554 align = MAX_OFILE_ALIGNMENT;
1557 /* On some machines, it is good to increase alignment sometimes. */
1558 if (! DECL_USER_ALIGN (decl))
1560 #ifdef DATA_ALIGNMENT
1561 align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1563 #ifdef CONSTANT_ALIGNMENT
1564 if (DECL_INITIAL (decl) != 0 && DECL_INITIAL (decl) != error_mark_node)
1565 align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
1569 /* Reset the alignment in case we have made it tighter, so we can benefit
1570 from it in get_pointer_alignment. */
1571 DECL_ALIGN (decl) = align;
1572 set_mem_align (decl_rtl, align);
1574 if (TREE_PUBLIC (decl))
1575 maybe_assemble_visibility (decl);
1577 /* Output any data that we will need to use the address of. */
1578 if (DECL_INITIAL (decl) == error_mark_node)
1579 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1580 else if (DECL_INITIAL (decl))
1581 reloc = output_addressed_constants (DECL_INITIAL (decl));
1582 resolve_unique_section (decl, reloc, flag_data_sections);
1584 /* Handle uninitialized definitions. */
1586 /* If the decl has been given an explicit section name, then it
1587 isn't common, and shouldn't be handled as such. */
1588 if (DECL_SECTION_NAME (decl) || dont_output_data)
1590 /* We don't implement common thread-local data at present. */
1591 else if (DECL_THREAD_LOCAL (decl))
1593 if (DECL_COMMON (decl))
1594 sorry ("thread-local COMMON data not implemented");
1596 #ifndef ASM_EMIT_BSS
1597 /* If the target can't output uninitialized but not common global data
1598 in .bss, then we have to use .data. */
1599 /* ??? We should handle .bss via select_section mechanisms rather than
1600 via special target hooks. That would eliminate this special case. */
1601 else if (!DECL_COMMON (decl))
1604 else if (DECL_INITIAL (decl) == 0
1605 || DECL_INITIAL (decl) == error_mark_node
1606 || (flag_zero_initialized_in_bss
1607 && initializer_zerop (DECL_INITIAL (decl))))
1609 unsigned HOST_WIDE_INT size = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
1610 unsigned HOST_WIDE_INT rounded = size;
1612 /* Don't allocate zero bytes of common,
1613 since that means "undefined external" in the linker. */
1617 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1618 so that each uninitialized object starts on such a boundary. */
1619 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
1620 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1621 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1623 /* Don't continue this line--convex cc version 4.1 would lose. */
1624 #if !defined(ASM_OUTPUT_ALIGNED_COMMON) && !defined(ASM_OUTPUT_ALIGNED_DECL_COMMON) && !defined(ASM_OUTPUT_ALIGNED_BSS)
1625 if ((unsigned HOST_WIDE_INT) DECL_ALIGN (decl) / BITS_PER_UNIT > rounded)
1627 (decl, "requested alignment for %s is greater than implemented alignment of %d",rounded);
1630 asm_emit_uninitialised (decl, name, size, rounded);
1635 /* Handle initialized definitions.
1636 Also handle uninitialized global definitions if -fno-common and the
1637 target doesn't support ASM_OUTPUT_BSS. */
1639 /* First make the assembler name(s) global if appropriate. */
1640 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
1641 globalize_decl (decl);
1643 /* Switch to the appropriate section. */
1644 variable_section (decl, reloc);
1646 /* dbxout.c needs to know this. */
1647 if (in_text_section ())
1648 DECL_IN_TEXT_SECTION (decl) = 1;
1650 /* Output the alignment of this data. */
1651 if (align > BITS_PER_UNIT)
1653 ASM_OUTPUT_ALIGN (asm_out_file,
1654 floor_log2 (DECL_ALIGN (decl) / BITS_PER_UNIT));
1657 /* Do any machine/system dependent processing of the object. */
1658 #ifdef ASM_DECLARE_OBJECT_NAME
1659 last_assemble_variable_decl = decl;
1660 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
1662 /* Standard thing is just output label for the object. */
1663 ASM_OUTPUT_LABEL (asm_out_file, name);
1664 #endif /* ASM_DECLARE_OBJECT_NAME */
1666 if (!dont_output_data)
1668 if (DECL_INITIAL (decl) && DECL_INITIAL (decl) != error_mark_node)
1669 /* Output the actual data. */
1670 output_constant (DECL_INITIAL (decl),
1671 tree_low_cst (DECL_SIZE_UNIT (decl), 1),
1674 /* Leave space for it. */
1675 assemble_zeros (tree_low_cst (DECL_SIZE_UNIT (decl), 1));
1679 /* Return 1 if type TYPE contains any pointers. */
1682 contains_pointers_p (type)
1685 switch (TREE_CODE (type))
1688 case REFERENCE_TYPE:
1689 /* I'm not sure whether OFFSET_TYPE needs this treatment,
1690 so I'll play safe and return 1. */
1696 case QUAL_UNION_TYPE:
1699 /* For a type that has fields, see if the fields have pointers. */
1700 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
1701 if (TREE_CODE (fields) == FIELD_DECL
1702 && contains_pointers_p (TREE_TYPE (fields)))
1708 /* An array type contains pointers if its element type does. */
1709 return contains_pointers_p (TREE_TYPE (type));
1716 /* Output something to declare an external symbol to the assembler.
1717 (Most assemblers don't need this, so we normally output nothing.)
1718 Do nothing if DECL is not external. */
1721 assemble_external (decl)
1722 tree decl ATTRIBUTE_UNUSED;
1724 /* Because most platforms do not define ASM_OUTPUT_EXTERNAL, the
1725 main body of this code is only rarely exercised. To provide some
1726 testing, on all platforms, we make sure that the ASM_OUT_FILE is
1727 open. If it's not, we should not be calling this function. */
1731 #ifdef ASM_OUTPUT_EXTERNAL
1732 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
1734 rtx rtl = DECL_RTL (decl);
1736 if (GET_CODE (rtl) == MEM && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
1737 && ! SYMBOL_REF_USED (XEXP (rtl, 0)))
1739 /* Some systems do require some output. */
1740 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
1741 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
1747 /* Similar, for calling a library function FUN. */
1750 assemble_external_libcall (fun)
1751 rtx fun ATTRIBUTE_UNUSED;
1753 #ifdef ASM_OUTPUT_EXTERNAL_LIBCALL
1754 /* Declare library function name external when first used, if nec. */
1755 if (! SYMBOL_REF_USED (fun))
1757 SYMBOL_REF_USED (fun) = 1;
1758 ASM_OUTPUT_EXTERNAL_LIBCALL (asm_out_file, fun);
1763 /* Declare the label NAME global. */
1766 assemble_global (name)
1767 const char *name ATTRIBUTE_UNUSED;
1769 ASM_GLOBALIZE_LABEL (asm_out_file, name);
1772 /* Assemble a label named NAME. */
1775 assemble_label (name)
1778 ASM_OUTPUT_LABEL (asm_out_file, name);
1781 /* Output to FILE a reference to the assembler name of a C-level name NAME.
1782 If NAME starts with a *, the rest of NAME is output verbatim.
1783 Otherwise NAME is transformed in an implementation-defined way
1784 (usually by the addition of an underscore).
1785 Many macros in the tm file are defined to call this function. */
1788 assemble_name (file, name)
1792 const char *real_name;
1795 real_name = (* targetm.strip_name_encoding) (name);
1797 id = maybe_get_identifier (real_name);
1799 TREE_SYMBOL_REFERENCED (id) = 1;
1802 fputs (&name[1], file);
1804 ASM_OUTPUT_LABELREF (file, name);
1807 /* Allocate SIZE bytes writable static space with a gensym name
1808 and return an RTX to refer to its address. */
1811 assemble_static_space (size)
1815 const char *namestring;
1819 if (flag_shared_data)
1823 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
1825 namestring = ggc_strdup (name);
1827 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
1829 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
1830 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
1833 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
1834 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
1837 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1838 so that each uninitialized object starts on such a boundary. */
1839 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
1840 int rounded ATTRIBUTE_UNUSED
1841 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
1842 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1843 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1844 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1851 /* Assemble the static constant template for function entry trampolines.
1852 This is done at most once per compilation.
1853 Returns an RTX for the address of the template. */
1855 #ifdef TRAMPOLINE_TEMPLATE
1857 assemble_trampoline_template ()
1863 /* By default, put trampoline templates in read-only data section. */
1865 #ifdef TRAMPOLINE_SECTION
1866 TRAMPOLINE_SECTION ();
1868 readonly_data_section ();
1871 /* Write the assembler code to define one. */
1872 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
1875 ASM_OUTPUT_ALIGN (asm_out_file, align);
1878 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LTRAMP", 0);
1879 TRAMPOLINE_TEMPLATE (asm_out_file);
1881 /* Record the rtl to refer to it. */
1882 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
1883 name = ggc_strdup (label);
1884 return gen_rtx_SYMBOL_REF (Pmode, name);
1888 /* A and B are either alignments or offsets. Return the minimum alignment
1889 that may be assumed after adding the two together. */
1891 static inline unsigned
1895 return (a | b) & -(a | b);
1898 /* Return the assembler directive for creating a given kind of integer
1899 object. SIZE is the number of bytes in the object and ALIGNED_P
1900 indicates whether it is known to be aligned. Return NULL if the
1901 assembly dialect has no such directive.
1903 The returned string should be printed at the start of a new line and
1904 be followed immediately by the object's initial value. */
1907 integer_asm_op (size, aligned_p)
1911 struct asm_int_op *ops;
1914 ops = &targetm.asm_out.aligned_op;
1916 ops = &targetm.asm_out.unaligned_op;
1921 return targetm.asm_out.byte_op;
1935 /* Use directive OP to assemble an integer object X. Print OP at the
1936 start of the line, followed immediately by the value of X. */
1939 assemble_integer_with_op (op, x)
1943 fputs (op, asm_out_file);
1944 output_addr_const (asm_out_file, x);
1945 fputc ('\n', asm_out_file);
1948 /* The default implementation of the asm_out.integer target hook. */
1951 default_assemble_integer (x, size, aligned_p)
1952 rtx x ATTRIBUTE_UNUSED;
1953 unsigned int size ATTRIBUTE_UNUSED;
1954 int aligned_p ATTRIBUTE_UNUSED;
1956 const char *op = integer_asm_op (size, aligned_p);
1957 return op && (assemble_integer_with_op (op, x), true);
1960 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
1961 the alignment of the integer in bits. Return 1 if we were able to output
1962 the constant, otherwise 0. If FORCE is non-zero, abort if we can't output
1966 assemble_integer (x, size, align, force)
1974 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
1976 /* See if the target hook can handle this kind of object. */
1977 if ((*targetm.asm_out.integer) (x, size, aligned_p))
1980 /* If the object is a multi-byte one, try splitting it up. Split
1981 it into words it if is multi-word, otherwise split it into bytes. */
1984 enum machine_mode omode, imode;
1985 unsigned int subalign;
1986 unsigned int subsize, i;
1988 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
1989 subalign = MIN (align, subsize * BITS_PER_UNIT);
1990 omode = mode_for_size (subsize * BITS_PER_UNIT, MODE_INT, 0);
1991 imode = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
1993 for (i = 0; i < size; i += subsize)
1995 rtx partial = simplify_subreg (omode, x, imode, i);
1996 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2002 /* If we've printed some of it, but not all of it, there's no going
2015 assemble_real (d, mode, align)
2017 enum machine_mode mode;
2022 unsigned int nalign = min_align (align, 32);
2024 switch (BITS_PER_UNIT)
2030 REAL_VALUE_TO_TARGET_SINGLE (d, l);
2031 assemble_integer (GEN_INT (l), 4, align, 1);
2034 REAL_VALUE_TO_TARGET_DOUBLE (d, data);
2035 assemble_integer (GEN_INT (data[0]), 4, align, 1);
2036 assemble_integer (GEN_INT (data[1]), 4, nalign, 1);
2039 REAL_VALUE_TO_TARGET_LONG_DOUBLE (d, data);
2040 assemble_integer (GEN_INT (data[0]), 4, align, 1);
2041 assemble_integer (GEN_INT (data[1]), 4, nalign, 1);
2042 assemble_integer (GEN_INT (data[2]), 4, nalign, 1);
2045 REAL_VALUE_TO_TARGET_LONG_DOUBLE (d, data);
2046 assemble_integer (GEN_INT (data[0]), 4, align, 1);
2047 assemble_integer (GEN_INT (data[1]), 4, nalign, 1);
2048 assemble_integer (GEN_INT (data[2]), 4, nalign, 1);
2049 assemble_integer (GEN_INT (data[3]), 4, nalign, 1);
2060 REAL_VALUE_TO_TARGET_SINGLE (d, l);
2061 assemble_integer (GEN_INT (l), 2, align, 1);
2064 REAL_VALUE_TO_TARGET_DOUBLE (d, data);
2065 assemble_integer (GEN_INT (data[0]), 2, align, 1);
2066 assemble_integer (GEN_INT (data[1]), 1, nalign, 1);
2077 REAL_VALUE_TO_TARGET_SINGLE (d, l);
2078 assemble_integer (GEN_INT (l), 1, align, 1);
2081 REAL_VALUE_TO_TARGET_DOUBLE (d, data);
2082 assemble_integer (GEN_INT (data[0]), 1, align, 1);
2083 assemble_integer (GEN_INT (data[1]), 1, nalign, 1);
2095 /* Given an expression EXP with a constant value,
2096 reduce it to the sum of an assembler symbol and an integer.
2097 Store them both in the structure *VALUE.
2098 Abort if EXP does not reduce. */
2100 struct addr_const GTY(())
2103 HOST_WIDE_INT offset;
2107 decode_addr_const (exp, value)
2109 struct addr_const *value;
2111 tree target = TREE_OPERAND (exp, 0);
2117 if (TREE_CODE (target) == COMPONENT_REF
2118 && host_integerp (byte_position (TREE_OPERAND (target, 1)), 0))
2121 offset += int_byte_position (TREE_OPERAND (target, 1));
2122 target = TREE_OPERAND (target, 0);
2124 else if (TREE_CODE (target) == ARRAY_REF
2125 || TREE_CODE (target) == ARRAY_RANGE_REF)
2127 offset += (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (target)), 1)
2128 * tree_low_cst (TREE_OPERAND (target, 1), 0));
2129 target = TREE_OPERAND (target, 0);
2135 switch (TREE_CODE (target))
2139 x = DECL_RTL (target);
2143 x = gen_rtx_MEM (FUNCTION_MODE,
2144 gen_rtx_LABEL_REF (VOIDmode,
2145 label_rtx (TREE_OPERAND (exp, 0))));
2153 /* This constant should have been output already, but we can't simply
2154 use TREE_CST_RTL since INTEGER_CST doesn't have one. */
2155 x = output_constant_def (target, 1);
2162 if (GET_CODE (x) != MEM)
2167 value->offset = offset;
2170 /* We do RTX_UNSPEC + XINT (blah), so nothing can go after RTX_UNSPEC. */
2171 enum kind { RTX_UNKNOWN, RTX_DOUBLE, RTX_VECTOR, RTX_INT, RTX_UNSPEC };
2172 struct rtx_const GTY(())
2174 ENUM_BITFIELD(kind) kind : 16;
2175 ENUM_BITFIELD(machine_mode) mode : 16;
2176 union rtx_const_un {
2178 struct addr_const GTY ((tag ("1"))) addr;
2179 struct rtx_const_u_di {
2182 } GTY ((tag ("0"))) di;
2184 /* The max vector size we have is 8 wide. This should be enough. */
2185 HOST_WIDE_INT veclo[16];
2186 HOST_WIDE_INT vechi[16];
2187 } GTY ((desc ("%1.kind >= RTX_INT"), descbits ("1"))) un;
2190 /* Uniquize all constants that appear in memory.
2191 Each constant in memory thus far output is recorded
2192 in `const_hash_table'. */
2194 struct constant_descriptor_tree GTY(())
2196 /* More constant_descriptors with the same hash code. */
2197 struct constant_descriptor_tree *next;
2199 /* The label of the constant. */
2202 /* A MEM for the constant. */
2205 /* The value of the constant. */
2210 #define MAX_HASH_TABLE 1009
2211 static GTY(()) struct constant_descriptor_tree *
2212 const_hash_table[MAX_HASH_TABLE];
2214 /* We maintain a hash table of STRING_CST values. Unless we are asked to force
2215 out a string constant, we defer output of the constants until we know
2216 they are actually used. This will be if something takes its address or if
2217 there is a usage of the string in the RTL of a function. */
2219 #define STRHASH(x) ((hashval_t) ((long) (x) >> 3))
2221 struct deferred_string GTY(())
2228 static GTY ((param_is (struct deferred_string))) htab_t const_str_htab;
2230 /* Returns a hash code for X (which is a really a
2231 struct deferred_string *). */
2234 const_str_htab_hash (x)
2237 return STRHASH (((const struct deferred_string *) x)->label);
2240 /* Returns non-zero if the value represented by X (which is really a
2241 struct deferred_string *) is the same as that given by Y
2242 (which is really a char *). */
2245 const_str_htab_eq (x, y)
2249 return (((const struct deferred_string *) x)->label == (const char *) y);
2252 /* Compute a hash code for a constant expression. */
2260 enum tree_code code = TREE_CODE (exp);
2262 /* Either set P and LEN to the address and len of something to hash and
2263 exit the switch or return a value. */
2268 p = (char *) &TREE_INT_CST (exp);
2269 len = sizeof TREE_INT_CST (exp);
2273 p = (char *) &TREE_REAL_CST (exp);
2274 len = sizeof TREE_REAL_CST (exp);
2278 p = TREE_STRING_POINTER (exp);
2279 len = TREE_STRING_LENGTH (exp);
2283 return (const_hash (TREE_REALPART (exp)) * 5
2284 + const_hash (TREE_IMAGPART (exp)));
2287 if (TREE_CODE (TREE_TYPE (exp)) == SET_TYPE)
2291 len = int_size_in_bytes (TREE_TYPE (exp));
2292 tmp = (char *) alloca (len);
2293 get_set_constructor_bytes (exp, (unsigned char *) tmp, len);
2301 /* For record type, include the type in the hashing.
2302 We do not do so for array types
2303 because (1) the sizes of the elements are sufficient
2304 and (2) distinct array types can have the same constructor.
2305 Instead, we include the array size because the constructor could
2307 if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE)
2308 hi = ((unsigned long) TREE_TYPE (exp) & ((1 << HASHBITS) - 1))
2311 hi = ((5 + int_size_in_bytes (TREE_TYPE (exp)))
2312 & ((1 << HASHBITS) - 1)) % MAX_HASH_TABLE;
2314 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link))
2315 if (TREE_VALUE (link))
2317 = (hi * 603 + const_hash (TREE_VALUE (link))) % MAX_HASH_TABLE;
2324 struct addr_const value;
2326 decode_addr_const (exp, &value);
2327 if (GET_CODE (value.base) == SYMBOL_REF)
2329 /* Don't hash the address of the SYMBOL_REF;
2330 only use the offset and the symbol name. */
2332 p = XSTR (value.base, 0);
2333 for (i = 0; p[i] != 0; i++)
2334 hi = ((hi * 613) + (unsigned) (p[i]));
2336 else if (GET_CODE (value.base) == LABEL_REF)
2337 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13;
2341 hi &= (1 << HASHBITS) - 1;
2342 hi %= MAX_HASH_TABLE;
2348 return (const_hash (TREE_OPERAND (exp, 0)) * 9
2349 + const_hash (TREE_OPERAND (exp, 1)));
2353 case NON_LVALUE_EXPR:
2354 return const_hash (TREE_OPERAND (exp, 0)) * 7 + 2;
2357 /* A language specific constant. Just hash the code. */
2358 return (int) code % MAX_HASH_TABLE;
2361 /* Compute hashing function */
2363 for (i = 0; i < len; i++)
2364 hi = ((hi * 613) + (unsigned) (p[i]));
2366 hi &= (1 << HASHBITS) - 1;
2367 hi %= MAX_HASH_TABLE;
2371 /* Compare t1 and t2, and return 1 only if they are known to result in
2372 the same bit pattern on output. */
2375 compare_constant (t1, t2)
2379 enum tree_code typecode;
2381 if (t1 == NULL_TREE)
2382 return t2 == NULL_TREE;
2383 if (t2 == NULL_TREE)
2386 if (TREE_CODE (t1) != TREE_CODE (t2))
2389 switch (TREE_CODE (t1))
2392 /* Integer constants are the same only if the same width of type. */
2393 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2395 return tree_int_cst_equal (t1, t2);
2398 /* Real constants are the same only if the same width of type. */
2399 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2402 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
2405 if (flag_writable_strings)
2408 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2411 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
2412 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
2413 TREE_STRING_LENGTH (t1)));
2416 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
2417 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
2420 typecode = TREE_CODE (TREE_TYPE (t1));
2421 if (typecode != TREE_CODE (TREE_TYPE (t2)))
2424 if (typecode == SET_TYPE)
2426 int len = int_size_in_bytes (TREE_TYPE (t2));
2427 unsigned char *tmp1, *tmp2;
2429 if (int_size_in_bytes (TREE_TYPE (t1)) != len)
2432 tmp1 = (unsigned char *) alloca (len);
2433 tmp2 = (unsigned char *) alloca (len);
2435 if (get_set_constructor_bytes (t1, tmp1, len) != NULL_TREE)
2437 if (get_set_constructor_bytes (t2, tmp2, len) != NULL_TREE)
2440 return memcmp (tmp1, tmp2, len) != 0;
2446 if (typecode == ARRAY_TYPE)
2448 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
2449 /* For arrays, check that the sizes all match. */
2450 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
2452 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
2457 /* For record and union constructors, require exact type
2459 if (TREE_TYPE (t1) != TREE_TYPE (t2))
2463 for (l1 = CONSTRUCTOR_ELTS (t1), l2 = CONSTRUCTOR_ELTS (t2);
2465 l1 = TREE_CHAIN (l1), l2 = TREE_CHAIN (l2))
2467 /* Check that each value is the same... */
2468 if (! compare_constant (TREE_VALUE (l1), TREE_VALUE (l2)))
2470 /* ... and that they apply to the same fields! */
2471 if (typecode == ARRAY_TYPE)
2473 if (! compare_constant (TREE_PURPOSE (l1),
2479 if (TREE_PURPOSE (l1) != TREE_PURPOSE (l2))
2484 return l1 == NULL_TREE && l2 == NULL_TREE;
2489 struct addr_const value1, value2;
2491 decode_addr_const (t1, &value1);
2492 decode_addr_const (t2, &value2);
2493 return (value1.offset == value2.offset
2494 && strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
2500 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
2501 && compare_constant(TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
2505 case NON_LVALUE_EXPR:
2506 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
2511 nt1 = (*lang_hooks.expand_constant) (t1);
2512 nt2 = (*lang_hooks.expand_constant) (t2);
2513 if (nt1 != t1 || nt2 != t2)
2514 return compare_constant (nt1, nt2);
2520 /* Should not get here. */
2524 /* Record a list of constant expressions that were passed to
2525 output_constant_def but that could not be output right away. */
2527 struct deferred_constant
2529 struct deferred_constant *next;
2535 static struct deferred_constant *deferred_constants;
2537 /* Another list of constants which should be output after the
2539 static struct deferred_constant *after_function_constants;
2541 /* Nonzero means defer output of addressed subconstants
2542 (i.e., those for which output_constant_def is called.) */
2543 static int defer_addressed_constants_flag;
2545 /* Start deferring output of subconstants. */
2548 defer_addressed_constants ()
2550 defer_addressed_constants_flag++;
2553 /* Stop deferring output of subconstants,
2554 and output now all those that have been deferred. */
2557 output_deferred_addressed_constants ()
2559 struct deferred_constant *p, *next;
2561 defer_addressed_constants_flag--;
2563 if (defer_addressed_constants_flag > 0)
2566 for (p = deferred_constants; p; p = next)
2568 output_constant_def_contents (p->exp, p->reloc, p->labelno);
2573 deferred_constants = 0;
2576 /* Output any constants which should appear after a function. */
2579 output_after_function_constants ()
2581 struct deferred_constant *p, *next;
2583 for (p = after_function_constants; p; p = next)
2585 output_constant_def_contents (p->exp, p->reloc, p->labelno);
2590 after_function_constants = 0;
2593 /* Make a copy of the whole tree structure for a constant. This
2594 handles the same types of nodes that compare_constant handles. */
2600 switch (TREE_CODE (exp))
2603 /* For ADDR_EXPR, we do not want to copy the decl whose address
2604 is requested. We do want to copy constants though. */
2605 if (TREE_CODE_CLASS (TREE_CODE (TREE_OPERAND (exp, 0))) == 'c')
2606 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
2607 copy_constant (TREE_OPERAND (exp, 0)));
2609 return copy_node (exp);
2614 return copy_node (exp);
2617 return build_complex (TREE_TYPE (exp),
2618 copy_constant (TREE_REALPART (exp)),
2619 copy_constant (TREE_IMAGPART (exp)));
2623 return build (TREE_CODE (exp), TREE_TYPE (exp),
2624 copy_constant (TREE_OPERAND (exp, 0)),
2625 copy_constant (TREE_OPERAND (exp, 1)));
2629 case NON_LVALUE_EXPR:
2630 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
2631 copy_constant (TREE_OPERAND (exp, 0)));
2635 tree copy = copy_node (exp);
2636 tree list = copy_list (CONSTRUCTOR_ELTS (exp));
2639 CONSTRUCTOR_ELTS (copy) = list;
2640 for (tail = list; tail; tail = TREE_CHAIN (tail))
2641 TREE_VALUE (tail) = copy_constant (TREE_VALUE (tail));
2642 if (TREE_CODE (TREE_TYPE (exp)) == SET_TYPE)
2643 for (tail = list; tail; tail = TREE_CHAIN (tail))
2644 TREE_PURPOSE (tail) = copy_constant (TREE_PURPOSE (tail));
2652 t = (*lang_hooks.expand_constant) (exp);
2654 return copy_constant (t);
2661 /* Return an rtx representing a reference to constant data in memory
2662 for the constant expression EXP.
2664 If assembler code for such a constant has already been output,
2665 return an rtx to refer to it.
2666 Otherwise, output such a constant in memory (or defer it for later)
2667 and generate an rtx for it.
2669 If DEFER is non-zero, the output of string constants can be deferred
2670 and output only if referenced in the function after all optimizations.
2672 The TREE_CST_RTL of EXP is set up to point to that rtx.
2673 The const_hash_table records which constants already have label strings. */
2676 output_constant_def (exp, defer)
2681 struct constant_descriptor_tree *desc;
2682 struct deferred_string **defstr;
2686 int after_function = 0;
2690 /* We can't just use the saved RTL if this is a deferred string constant
2691 and we are not to defer anymore. */
2692 if (TREE_CODE (exp) != INTEGER_CST && TREE_CST_RTL (exp)
2693 && (defer || !STRING_POOL_ADDRESS_P (XEXP (TREE_CST_RTL (exp), 0))))
2694 return TREE_CST_RTL (exp);
2696 /* Make sure any other constants whose addresses appear in EXP
2697 are assigned label numbers. */
2699 reloc = output_addressed_constants (exp);
2701 /* Compute hash code of EXP. Search the descriptors for that hash code
2702 to see if any of them describes EXP. If yes, the descriptor records
2703 the label number already assigned. */
2705 hash = const_hash (exp) % MAX_HASH_TABLE;
2707 for (desc = const_hash_table[hash]; desc; desc = desc->next)
2708 if (compare_constant (exp, desc->value))
2713 /* No constant equal to EXP is known to have been output.
2714 Make a constant descriptor to enter EXP in the hash table.
2715 Assign the label number and record it in the descriptor for
2716 future calls to this function to find. */
2718 /* Create a string containing the label name, in LABEL. */
2719 labelno = const_labelno++;
2720 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
2722 desc = ggc_alloc (sizeof (*desc));
2723 desc->next = const_hash_table[hash];
2724 desc->label = ggc_strdup (label);
2725 desc->value = copy_constant (exp);
2726 const_hash_table[hash] = desc;
2728 /* We have a symbol name; construct the SYMBOL_REF and the MEM. */
2730 = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)),
2731 gen_rtx_SYMBOL_REF (Pmode, desc->label));
2733 set_mem_attributes (rtl, exp, 1);
2734 set_mem_alias_set (rtl, 0);
2735 set_mem_alias_set (rtl, const_alias_set);
2742 if (TREE_CODE (exp) != INTEGER_CST)
2743 TREE_CST_RTL (exp) = rtl;
2745 /* Optionally set flags or add text to the name to record information
2746 such as that it is a function name. If the name is changed, the macro
2747 ASM_OUTPUT_LABELREF will have to know how to strip this information. */
2748 /* A previously-processed constant would already have section info
2752 /* Take care not to invoke targetm.encode_section_info for
2753 constants which don't have a TREE_CST_RTL. */
2754 if (TREE_CODE (exp) != INTEGER_CST)
2755 (*targetm.encode_section_info) (exp, true);
2758 desc->label = XSTR (XEXP (desc->rtl, 0), 0);
2761 #ifdef CONSTANT_AFTER_FUNCTION_P
2762 if (current_function_decl != 0
2763 && CONSTANT_AFTER_FUNCTION_P (exp))
2768 && STRING_POOL_ADDRESS_P (XEXP (rtl, 0))
2769 && (!defer || defer_addressed_constants_flag || after_function))
2771 defstr = (struct deferred_string **)
2772 htab_find_slot_with_hash (const_str_htab, desc->label,
2773 STRHASH (desc->label), NO_INSERT);
2776 /* If the string is currently deferred but we need to output it now,
2777 remove it from deferred string hash table. */
2779 labelno = (*defstr)->labelno;
2780 STRING_POOL_ADDRESS_P (XEXP (rtl, 0)) = 0;
2781 htab_clear_slot (const_str_htab, (void **) defstr);
2785 /* If this is the first time we've seen this particular constant,
2786 output it (or defer its output for later). */
2789 if (defer_addressed_constants_flag || after_function)
2791 struct deferred_constant *p
2792 = (struct deferred_constant *)
2793 xmalloc (sizeof (struct deferred_constant));
2795 p->exp = desc->value;
2797 p->labelno = labelno;
2800 p->next = after_function_constants;
2801 after_function_constants = p;
2805 p->next = deferred_constants;
2806 deferred_constants = p;
2811 /* Do no output if -fsyntax-only. */
2812 if (! flag_syntax_only)
2814 if (TREE_CODE (exp) != STRING_CST
2816 || flag_writable_strings
2817 || (defstr = (struct deferred_string **)
2818 htab_find_slot_with_hash (const_str_htab,
2820 STRHASH (desc->label),
2822 output_constant_def_contents (exp, reloc, labelno);
2825 struct deferred_string *p;
2827 p = (struct deferred_string *)
2828 ggc_alloc (sizeof (struct deferred_string));
2830 p->exp = desc->value;
2831 p->label = desc->label;
2832 p->labelno = labelno;
2834 STRING_POOL_ADDRESS_P (XEXP (rtl, 0)) = 1;
2843 /* Now output assembler code to define the label for EXP,
2844 and follow it with the data of EXP. */
2847 output_constant_def_contents (exp, reloc, labelno)
2854 /* Align the location counter as required by EXP's data type. */
2855 align = TYPE_ALIGN (TREE_TYPE (exp));
2856 #ifdef CONSTANT_ALIGNMENT
2857 align = CONSTANT_ALIGNMENT (exp, align);
2860 if (IN_NAMED_SECTION (exp))
2861 named_section (exp, NULL, reloc);
2863 (*targetm.asm_out.select_section) (exp, reloc, align);
2865 if (align > BITS_PER_UNIT)
2867 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2870 /* Output the label itself. */
2871 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LC", labelno);
2873 /* Output the value of EXP. */
2874 output_constant (exp,
2875 (TREE_CODE (exp) == STRING_CST
2876 ? MAX (TREE_STRING_LENGTH (exp),
2877 int_size_in_bytes (TREE_TYPE (exp)))
2878 : int_size_in_bytes (TREE_TYPE (exp))),
2883 /* Used in the hash tables to avoid outputting the same constant
2884 twice. Unlike 'struct constant_descriptor_tree', RTX constants
2885 are output once per function, not once per file; there seems
2886 to be no reason for the difference. */
2888 struct constant_descriptor_rtx GTY(())
2890 /* More constant_descriptors with the same hash code. */
2891 struct constant_descriptor_rtx *next;
2893 /* The label of the constant. */
2896 /* A MEM for the constant. */
2899 /* The value of the constant. */
2900 struct rtx_const value;
2903 /* Structure to represent sufficient information about a constant so that
2904 it can be output when the constant pool is output, so that function
2905 integration can be done, and to simplify handling on machines that reference
2906 constant pool as base+displacement. */
2908 struct pool_constant GTY(())
2910 struct constant_descriptor_rtx *desc;
2911 struct pool_constant *next;
2912 struct pool_constant *next_sym;
2914 enum machine_mode mode;
2917 HOST_WIDE_INT offset;
2921 /* Hash code for a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true.
2922 The argument is XSTR (... , 0) */
2924 #define SYMHASH(LABEL) \
2925 ((((unsigned long) (LABEL)) & ((1 << HASHBITS) - 1)) % MAX_RTX_HASH_TABLE)
2927 /* Initialize constant pool hashing for a new function. */
2930 init_varasm_status (f)
2933 struct varasm_status *p;
2934 p = (struct varasm_status *) ggc_alloc (sizeof (struct varasm_status));
2936 p->x_const_rtx_hash_table
2937 = ((struct constant_descriptor_rtx **)
2938 ggc_alloc_cleared (MAX_RTX_HASH_TABLE
2939 * sizeof (struct constant_descriptor_rtx *)));
2940 p->x_const_rtx_sym_hash_table
2941 = ((struct pool_constant **)
2942 ggc_alloc_cleared (MAX_RTX_HASH_TABLE
2943 * sizeof (struct pool_constant *)));
2945 p->x_first_pool = p->x_last_pool = 0;
2946 p->x_pool_offset = 0;
2950 /* Express an rtx for a constant integer (perhaps symbolic)
2951 as the sum of a symbol or label plus an explicit integer.
2952 They are stored into VALUE. */
2955 decode_rtx_const (mode, x, value)
2956 enum machine_mode mode;
2958 struct rtx_const *value;
2960 /* Clear the whole structure, including any gaps. */
2961 memset (value, 0, sizeof (struct rtx_const));
2963 value->kind = RTX_INT; /* Most usual kind. */
2966 switch (GET_CODE (x))
2969 value->kind = RTX_DOUBLE;
2970 if (GET_MODE (x) != VOIDmode)
2972 value->mode = GET_MODE (x);
2973 REAL_VALUE_FROM_CONST_DOUBLE (value->un.du, x);
2977 value->un.di.low = CONST_DOUBLE_LOW (x);
2978 value->un.di.high = CONST_DOUBLE_HIGH (x);
2987 units = CONST_VECTOR_NUNITS (x);
2988 value->kind = RTX_VECTOR;
2991 for (i = 0; i < units; ++i)
2993 elt = CONST_VECTOR_ELT (x, i);
2994 if (GET_MODE_CLASS (mode) == MODE_VECTOR_INT)
2996 value->un.veclo[i] = (HOST_WIDE_INT) INTVAL (elt);
2997 value->un.vechi[i] = 0;
2999 else if (GET_MODE_CLASS (mode) == MODE_VECTOR_FLOAT)
3001 value->un.veclo[i] = (HOST_WIDE_INT) CONST_DOUBLE_LOW (elt);
3002 value->un.vechi[i] = (HOST_WIDE_INT) CONST_DOUBLE_HIGH (elt);
3011 value->un.addr.offset = INTVAL (x);
3017 value->un.addr.base = x;
3022 if (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == CONST_INT)
3024 value->un.addr.base = XEXP (x, 0);
3025 value->un.addr.offset = INTVAL (XEXP (x, 1));
3027 else if (GET_CODE (x) == MINUS && GET_CODE (XEXP (x, 1)) == CONST_INT)
3029 value->un.addr.base = XEXP (x, 0);
3030 value->un.addr.offset = - INTVAL (XEXP (x, 1));
3034 value->un.addr.base = x;
3035 value->un.addr.offset = 0;
3040 value->kind = RTX_UNKNOWN;
3044 if (value->kind == RTX_INT && value->un.addr.base != 0
3045 && GET_CODE (value->un.addr.base) == UNSPEC)
3047 /* For a simple UNSPEC, the base is set to the
3048 operand, the kind field is set to the index of
3049 the unspec expression.
3050 Together with the code below, in case that
3051 the operand is a SYMBOL_REF or LABEL_REF,
3052 the address of the string or the code_label
3053 is taken as base. */
3054 if (XVECLEN (value->un.addr.base, 0) == 1)
3056 value->kind = RTX_UNSPEC + XINT (value->un.addr.base, 1);
3057 value->un.addr.base = XVECEXP (value->un.addr.base, 0, 0);
3061 if (value->kind > RTX_DOUBLE && value->un.addr.base != 0)
3062 switch (GET_CODE (value->un.addr.base))
3066 /* Use the string's address, not the SYMBOL_REF's address,
3067 for the sake of addresses of library routines. */
3068 value->un.addr.base = (rtx) XSTR (value->un.addr.base, 0);
3073 /* For a LABEL_REF, compare labels. */
3074 value->un.addr.base = XEXP (value->un.addr.base, 0);
3081 /* Given a MINUS expression, simplify it if both sides
3082 include the same symbol. */
3085 simplify_subtraction (x)
3088 struct rtx_const val0, val1;
3090 decode_rtx_const (GET_MODE (x), XEXP (x, 0), &val0);
3091 decode_rtx_const (GET_MODE (x), XEXP (x, 1), &val1);
3093 if (val0.kind > RTX_DOUBLE
3094 && val0.kind == val1.kind
3095 && val0.un.addr.base == val1.un.addr.base)
3096 return GEN_INT (val0.un.addr.offset - val1.un.addr.offset);
3101 /* Compute a hash code for a constant RTL expression. */
3104 const_hash_rtx (mode, x)
3105 enum machine_mode mode;
3111 struct rtx_const value;
3112 decode_rtx_const (mode, x, &value);
3114 /* Compute hashing function */
3116 for (i = 0; i < sizeof value / sizeof (int); i++)
3117 hi += ((int *) &value)[i];
3119 hi &= (1 << HASHBITS) - 1;
3120 hi %= MAX_RTX_HASH_TABLE;
3124 /* Compare a constant rtl object X with a constant-descriptor DESC.
3125 Return 1 if DESC describes a constant with the same value as X. */
3128 compare_constant_rtx (mode, x, desc)
3129 enum machine_mode mode;
3131 struct constant_descriptor_rtx *desc;
3133 struct rtx_const value;
3135 decode_rtx_const (mode, x, &value);
3137 /* Compare constant contents. */
3138 return memcmp (&value, &desc->value, sizeof (struct rtx_const)) == 0;
3141 /* Construct a constant descriptor for the rtl-expression X.
3142 It is up to the caller to enter the descriptor in the hash table. */
3144 static struct constant_descriptor_rtx *
3145 record_constant_rtx (mode, x)
3146 enum machine_mode mode;
3149 struct constant_descriptor_rtx *ptr;
3151 ptr = (struct constant_descriptor_rtx *) ggc_alloc (sizeof (*ptr));
3152 decode_rtx_const (mode, x, &ptr->value);
3157 /* Given a constant rtx X, return a MEM for the location in memory at which
3158 this constant has been placed. Return 0 if it not has been placed yet. */
3161 mem_for_const_double (x)
3164 enum machine_mode mode = GET_MODE (x);
3165 struct constant_descriptor_rtx *desc;
3167 for (desc = const_rtx_hash_table[const_hash_rtx (mode, x)]; desc;
3169 if (compare_constant_rtx (mode, x, desc))
3175 /* Given a constant rtx X, make (or find) a memory constant for its value
3176 and return a MEM rtx to refer to it in memory. */
3179 force_const_mem (mode, x)
3180 enum machine_mode mode;
3184 struct constant_descriptor_rtx *desc;
3187 struct pool_constant *pool;
3190 /* Compute hash code of X. Search the descriptors for that hash code
3191 to see if any of them describes X. If yes, we have an rtx to use. */
3192 hash = const_hash_rtx (mode, x);
3193 for (desc = const_rtx_hash_table[hash]; desc; desc = desc->next)
3194 if (compare_constant_rtx (mode, x, desc))
3197 /* No constant equal to X is known to have been output.
3198 Make a constant descriptor to enter X in the hash table
3199 and make a MEM for it. */
3200 desc = record_constant_rtx (mode, x);
3201 desc->next = const_rtx_hash_table[hash];
3202 const_rtx_hash_table[hash] = desc;
3204 /* Align the location counter as required by EXP's data type. */
3205 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
3206 #ifdef CONSTANT_ALIGNMENT
3207 align = CONSTANT_ALIGNMENT (make_tree ((*lang_hooks.types.type_for_mode)
3208 (mode, 0), x), align);
3211 pool_offset += (align / BITS_PER_UNIT) - 1;
3212 pool_offset &= ~ ((align / BITS_PER_UNIT) - 1);
3214 if (GET_CODE (x) == LABEL_REF)
3215 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
3217 /* Allocate a pool constant descriptor, fill it in, and chain it in. */
3218 pool = (struct pool_constant *) ggc_alloc (sizeof (struct pool_constant));
3222 pool->labelno = const_labelno;
3223 pool->align = align;
3224 pool->offset = pool_offset;
3231 last_pool->next = pool;
3234 pool_offset += GET_MODE_SIZE (mode);
3236 /* Create a string containing the label name, in LABEL. */
3237 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3241 /* Construct the SYMBOL_REF and the MEM. */
3243 pool->desc->rtl = def
3244 = gen_rtx_MEM (mode, gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label)));
3245 set_mem_alias_set (def, const_alias_set);
3246 set_mem_attributes (def, (*lang_hooks.types.type_for_mode) (mode, 0), 1);
3247 RTX_UNCHANGING_P (def) = 1;
3249 /* Add label to symbol hash table. */
3250 hash = SYMHASH (XSTR (XEXP (def, 0), 0));
3251 pool->next_sym = const_rtx_sym_hash_table[hash];
3252 const_rtx_sym_hash_table[hash] = pool;
3254 /* Mark the symbol_ref as belonging to this constants pool. */
3255 CONSTANT_POOL_ADDRESS_P (XEXP (def, 0)) = 1;
3256 current_function_uses_const_pool = 1;
3261 /* Given a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true, return a pointer to
3262 the corresponding pool_constant structure. */
3264 static struct pool_constant *
3265 find_pool_constant (f, addr)
3269 struct pool_constant *pool;
3270 const char *label = XSTR (addr, 0);
3272 for (pool = f->varasm->x_const_rtx_sym_hash_table[SYMHASH (label)]; pool;
3273 pool = pool->next_sym)
3274 if (XSTR (XEXP (pool->desc->rtl, 0), 0) == label)
3280 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3283 get_pool_constant (addr)
3286 return (find_pool_constant (cfun, addr))->constant;
3289 /* Given a constant pool SYMBOL_REF, return the corresponding constant
3290 and whether it has been output or not. */
3293 get_pool_constant_mark (addr, pmarked)
3297 struct pool_constant *pool = find_pool_constant (cfun, addr);
3298 *pmarked = (pool->mark != 0);
3299 return pool->constant;
3302 /* Likewise, but for the constant pool of a specific function. */
3305 get_pool_constant_for_function (f, addr)
3309 return (find_pool_constant (f, addr))->constant;
3312 /* Similar, return the mode. */
3315 get_pool_mode (addr)
3318 return (find_pool_constant (cfun, addr))->mode;
3322 get_pool_mode_for_function (f, addr)
3326 return (find_pool_constant (f, addr))->mode;
3329 /* Similar, return the offset in the constant pool. */
3332 get_pool_offset (addr)
3335 return (find_pool_constant (cfun, addr))->offset;
3338 /* Return the size of the constant pool. */
3346 /* Write all the constants in the constant pool. */
3349 output_constant_pool (fnname, fndecl)
3350 const char *fnname ATTRIBUTE_UNUSED;
3351 tree fndecl ATTRIBUTE_UNUSED;
3353 struct pool_constant *pool;
3357 /* It is possible for gcc to call force_const_mem and then to later
3358 discard the instructions which refer to the constant. In such a
3359 case we do not need to output the constant. */
3360 mark_constant_pool ();
3362 #ifdef ASM_OUTPUT_POOL_PROLOGUE
3363 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool_offset);
3366 for (pool = first_pool; pool; pool = pool->next)
3375 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3376 whose CODE_LABEL has been deleted. This can occur if a jump table
3377 is eliminated by optimization. If so, write a constant of zero
3378 instead. Note that this can also happen by turning the
3379 CODE_LABEL into a NOTE. */
3380 /* ??? This seems completely and utterly wrong. Certainly it's
3381 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3382 functioning even with INSN_DELETED_P and friends. */
3385 switch (GET_CODE (x))
3388 if (GET_CODE (XEXP (x, 0)) != PLUS
3389 || GET_CODE (XEXP (XEXP (x, 0), 0)) != LABEL_REF)
3391 tmp = XEXP (XEXP (x, 0), 0);
3396 if (INSN_DELETED_P (tmp)
3397 || (GET_CODE (tmp) == NOTE
3398 && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_DELETED))
3409 /* First switch to correct section. */
3410 (*targetm.asm_out.select_rtx_section) (pool->mode, x, pool->align);
3412 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3413 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, pool->mode,
3414 pool->align, pool->labelno, done);
3417 assemble_align (pool->align);
3419 /* Output the label. */
3420 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LC", pool->labelno);
3422 /* Output the value of the constant itself. */
3423 switch (GET_MODE_CLASS (pool->mode))
3426 if (GET_CODE (x) != CONST_DOUBLE)
3429 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3430 assemble_real (r, pool->mode, pool->align);
3434 case MODE_PARTIAL_INT:
3435 assemble_integer (x, GET_MODE_SIZE (pool->mode), pool->align, 1);
3438 case MODE_VECTOR_FLOAT:
3443 if (GET_CODE (x) != CONST_VECTOR)
3446 units = CONST_VECTOR_NUNITS (x);
3448 for (i = 0; i < units; i++)
3450 elt = CONST_VECTOR_ELT (x, i);
3451 REAL_VALUE_FROM_CONST_DOUBLE (r, elt);
3452 assemble_real (r, GET_MODE_INNER (pool->mode), pool->align);
3457 case MODE_VECTOR_INT:
3462 if (GET_CODE (x) != CONST_VECTOR)
3465 units = CONST_VECTOR_NUNITS (x);
3467 for (i = 0; i < units; i++)
3469 elt = CONST_VECTOR_ELT (x, i);
3470 assemble_integer (elt, GET_MODE_UNIT_SIZE (pool->mode),
3480 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3485 #ifdef ASM_OUTPUT_POOL_EPILOGUE
3486 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool_offset);
3489 /* Done with this pool. */
3490 first_pool = last_pool = 0;
3493 /* Look through the instructions for this function, and mark all the
3494 entries in the constant pool which are actually being used.
3495 Emit used deferred strings. */
3498 mark_constant_pool ()
3502 struct pool_constant *pool;
3504 if (first_pool == 0 && htab_elements (const_str_htab) == 0)
3507 for (pool = first_pool; pool; pool = pool->next)
3510 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3512 mark_constants (PATTERN (insn));
3514 for (link = current_function_epilogue_delay_list;
3516 link = XEXP (link, 1))
3518 insn = XEXP (link, 0);
3521 mark_constants (PATTERN (insn));
3525 /* Look through appropriate parts of X, marking all entries in the
3526 constant pool which are actually being used. Entries that are only
3527 referenced by other constants are also marked as used. Emit
3528 deferred strings that are used. */
3535 const char *format_ptr;
3540 if (GET_CODE (x) == SYMBOL_REF)
3542 mark_constant (&x, NULL);
3546 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3547 insns, not any notes that may be attached. We don't want to mark
3548 a constant just because it happens to appear in a REG_EQUIV note. */
3551 mark_constants (PATTERN (x));
3555 format_ptr = GET_RTX_FORMAT (GET_CODE (x));
3557 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (x)); i++)
3559 switch (*format_ptr++)
3562 mark_constants (XEXP (x, i));
3566 if (XVEC (x, i) != 0)
3570 for (j = 0; j < XVECLEN (x, i); j++)
3571 mark_constants (XVECEXP (x, i, j));
3591 /* Given a SYMBOL_REF CURRENT_RTX, mark it and all constants it refers
3592 to as used. Emit referenced deferred strings. This function can
3593 be used with for_each_rtx to mark all SYMBOL_REFs in an rtx. */
3596 mark_constant (current_rtx, data)
3598 void *data ATTRIBUTE_UNUSED;
3600 rtx x = *current_rtx;
3605 else if (GET_CODE (x) == SYMBOL_REF)
3607 if (CONSTANT_POOL_ADDRESS_P (x))
3609 struct pool_constant *pool = find_pool_constant (cfun, x);
3610 if (pool->mark == 0)
3613 for_each_rtx (&(pool->constant), &mark_constant, NULL);
3618 else if (STRING_POOL_ADDRESS_P (x))
3620 struct deferred_string **defstr;
3622 defstr = (struct deferred_string **)
3623 htab_find_slot_with_hash (const_str_htab, XSTR (x, 0),
3624 STRHASH (XSTR (x, 0)), NO_INSERT);
3627 struct deferred_string *p = *defstr;
3629 STRING_POOL_ADDRESS_P (x) = 0;
3630 output_constant_def_contents (p->exp, 0, p->labelno);
3631 htab_clear_slot (const_str_htab, (void **) defstr);
3638 /* Find all the constants whose addresses are referenced inside of EXP,
3639 and make sure assembler code with a label has been output for each one.
3640 Indicate whether an ADDR_EXPR has been encountered. */
3643 output_addressed_constants (exp)
3649 /* Give the front-end a chance to convert VALUE to something that
3650 looks more like a constant to the back-end. */
3651 exp = (*lang_hooks.expand_constant) (exp);
3653 switch (TREE_CODE (exp))
3656 /* Go inside any operations that get_inner_reference can handle and see
3657 if what's inside is a constant: no need to do anything here for
3658 addresses of variables or functions. */
3659 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
3660 tem = TREE_OPERAND (tem, 0))
3663 if (TREE_CODE_CLASS (TREE_CODE (tem)) == 'c'
3664 || TREE_CODE (tem) == CONSTRUCTOR)
3665 output_constant_def (tem, 0);
3667 if (TREE_PUBLIC (tem))
3675 reloc = output_addressed_constants (TREE_OPERAND (exp, 0));
3676 reloc |= output_addressed_constants (TREE_OPERAND (exp, 1));
3681 case NON_LVALUE_EXPR:
3682 reloc = output_addressed_constants (TREE_OPERAND (exp, 0));
3686 for (tem = CONSTRUCTOR_ELTS (exp); tem; tem = TREE_CHAIN (tem))
3687 if (TREE_VALUE (tem) != 0)
3688 reloc |= output_addressed_constants (TREE_VALUE (tem));
3698 /* Return nonzero if VALUE is a valid constant-valued expression
3699 for use in initializing a static variable; one that can be an
3700 element of a "constant" initializer.
3702 Return null_pointer_node if the value is absolute;
3703 if it is relocatable, return the variable that determines the relocation.
3704 We assume that VALUE has been folded as much as possible;
3705 therefore, we do not need to check for such things as
3706 arithmetic-combinations of integers. */
3709 initializer_constant_valid_p (value, endtype)
3713 /* Give the front-end a chance to convert VALUE to something that
3714 looks more like a constant to the back-end. */
3715 value = (*lang_hooks.expand_constant) (value);
3717 switch (TREE_CODE (value))
3720 if ((TREE_CODE (TREE_TYPE (value)) == UNION_TYPE
3721 || TREE_CODE (TREE_TYPE (value)) == RECORD_TYPE)
3722 && TREE_CONSTANT (value)
3723 && CONSTRUCTOR_ELTS (value))
3725 initializer_constant_valid_p (TREE_VALUE (CONSTRUCTOR_ELTS (value)),
3728 return TREE_STATIC (value) ? null_pointer_node : 0;
3735 return null_pointer_node;
3739 return staticp (TREE_OPERAND (value, 0)) ? TREE_OPERAND (value, 0) : 0;
3741 case VIEW_CONVERT_EXPR:
3742 case NON_LVALUE_EXPR:
3743 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3747 /* Allow conversions between pointer types. */
3748 if (POINTER_TYPE_P (TREE_TYPE (value))
3749 && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3750 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3752 /* Allow conversions between real types. */
3753 if (FLOAT_TYPE_P (TREE_TYPE (value))
3754 && FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3755 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3757 /* Allow length-preserving conversions between integer types. */
3758 if (INTEGRAL_TYPE_P (TREE_TYPE (value))
3759 && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0)))
3760 && (TYPE_PRECISION (TREE_TYPE (value))
3761 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0)))))
3762 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3764 /* Allow conversions between other integer types only if
3766 if (INTEGRAL_TYPE_P (TREE_TYPE (value))
3767 && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3769 tree inner = initializer_constant_valid_p (TREE_OPERAND (value, 0),
3771 if (inner == null_pointer_node)
3772 return null_pointer_node;
3776 /* Allow (int) &foo provided int is as wide as a pointer. */
3777 if (INTEGRAL_TYPE_P (TREE_TYPE (value))
3778 && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0)))
3779 && (TYPE_PRECISION (TREE_TYPE (value))
3780 >= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0)))))
3781 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
3784 /* Likewise conversions from int to pointers, but also allow
3785 conversions from 0. */
3786 if (POINTER_TYPE_P (TREE_TYPE (value))
3787 && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3789 if (integer_zerop (TREE_OPERAND (value, 0)))
3790 return null_pointer_node;
3791 else if (TYPE_PRECISION (TREE_TYPE (value))
3792 <= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0))))
3793 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
3797 /* Allow conversions to union types if the value inside is okay. */
3798 if (TREE_CODE (TREE_TYPE (value)) == UNION_TYPE)
3799 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
3804 if (! INTEGRAL_TYPE_P (endtype)
3805 || TYPE_PRECISION (endtype) >= POINTER_SIZE)
3807 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0),
3809 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1),
3811 /* If either term is absolute, use the other terms relocation. */
3812 if (valid0 == null_pointer_node)
3814 if (valid1 == null_pointer_node)
3820 if (! INTEGRAL_TYPE_P (endtype)
3821 || TYPE_PRECISION (endtype) >= POINTER_SIZE)
3823 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0),
3825 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1),
3827 /* Win if second argument is absolute. */
3828 if (valid1 == null_pointer_node)
3830 /* Win if both arguments have the same relocation.
3831 Then the value is absolute. */
3832 if (valid0 == valid1 && valid0 != 0)
3833 return null_pointer_node;
3835 /* Since GCC guarantees that string constants are unique in the
3836 generated code, a subtraction between two copies of the same
3837 constant string is absolute. */
3838 if (valid0 && TREE_CODE (valid0) == STRING_CST &&
3839 valid1 && TREE_CODE (valid1) == STRING_CST &&
3840 TREE_STRING_POINTER (valid0) == TREE_STRING_POINTER (valid1))
3841 return null_pointer_node;
3844 /* Support differences between labels. */
3845 if (INTEGRAL_TYPE_P (endtype))
3848 op0 = TREE_OPERAND (value, 0);
3849 op1 = TREE_OPERAND (value, 1);
3851 /* Like STRIP_NOPS except allow the operand mode to widen.
3852 This works around a feature of fold that simplfies
3853 (int)(p1 - p2) to ((int)p1 - (int)p2) under the theory
3854 that the narrower operation is cheaper. */
3856 while (TREE_CODE (op0) == NOP_EXPR
3857 || TREE_CODE (op0) == CONVERT_EXPR
3858 || TREE_CODE (op0) == NON_LVALUE_EXPR)
3860 tree inner = TREE_OPERAND (op0, 0);
3861 if (inner == error_mark_node
3862 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
3863 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
3864 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
3869 while (TREE_CODE (op1) == NOP_EXPR
3870 || TREE_CODE (op1) == CONVERT_EXPR
3871 || TREE_CODE (op1) == NON_LVALUE_EXPR)
3873 tree inner = TREE_OPERAND (op1, 0);
3874 if (inner == error_mark_node
3875 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
3876 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
3877 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
3882 if (TREE_CODE (op0) == ADDR_EXPR
3883 && TREE_CODE (TREE_OPERAND (op0, 0)) == LABEL_DECL
3884 && TREE_CODE (op1) == ADDR_EXPR
3885 && TREE_CODE (TREE_OPERAND (op1, 0)) == LABEL_DECL)
3886 return null_pointer_node;
3897 /* Output assembler code for constant EXP to FILE, with no label.
3898 This includes the pseudo-op such as ".int" or ".byte", and a newline.
3899 Assumes output_addressed_constants has been done on EXP already.
3901 Generate exactly SIZE bytes of assembler data, padding at the end
3902 with zeros if necessary. SIZE must always be specified.
3904 SIZE is important for structure constructors,
3905 since trailing members may have been omitted from the constructor.
3906 It is also important for initialization of arrays from string constants
3907 since the full length of the string constant might not be wanted.
3908 It is also needed for initialization of unions, where the initializer's
3909 type is just one member, and that may not be as long as the union.
3911 There a case in which we would fail to output exactly SIZE bytes:
3912 for a structure constructor that wants to produce more than SIZE bytes.
3913 But such constructors will never be generated for any possible input.
3915 ALIGN is the alignment of the data in bits. */
3918 output_constant (exp, size, align)
3923 enum tree_code code;
3924 HOST_WIDE_INT thissize;
3926 /* Some front-ends use constants other than the standard language-indepdent
3927 varieties, but which may still be output directly. Give the front-end a
3928 chance to convert EXP to a language-independent representation. */
3929 exp = (*lang_hooks.expand_constant) (exp);
3931 if (size == 0 || flag_syntax_only)
3934 /* Eliminate any conversions since we'll be outputting the underlying
3936 while (TREE_CODE (exp) == NOP_EXPR || TREE_CODE (exp) == CONVERT_EXPR
3937 || TREE_CODE (exp) == NON_LVALUE_EXPR
3938 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
3939 exp = TREE_OPERAND (exp, 0);
3941 code = TREE_CODE (TREE_TYPE (exp));
3942 thissize = int_size_in_bytes (TREE_TYPE (exp));
3944 /* Allow a constructor with no elements for any data type.
3945 This means to fill the space with zeros. */
3946 if (TREE_CODE (exp) == CONSTRUCTOR && CONSTRUCTOR_ELTS (exp) == 0)
3948 assemble_zeros (size);
3952 if (TREE_CODE (exp) == FDESC_EXPR)
3954 #ifdef ASM_OUTPUT_FDESC
3955 HOST_WIDE_INT part = tree_low_cst (TREE_OPERAND (exp, 1), 0);
3956 tree decl = TREE_OPERAND (exp, 0);
3957 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
3964 /* Now output the underlying data. If we've handling the padding, return.
3965 Otherwise, break and ensure THISSIZE is the size written. */
3973 case REFERENCE_TYPE:
3974 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
3975 EXPAND_INITIALIZER),
3977 error ("initializer for integer value is too complicated");
3981 if (TREE_CODE (exp) != REAL_CST)
3982 error ("initializer for floating value is not a floating constant");
3984 assemble_real (TREE_REAL_CST (exp),
3985 mode_for_size (size * BITS_PER_UNIT, MODE_FLOAT, 0),
3990 output_constant (TREE_REALPART (exp), thissize / 2, align);
3991 output_constant (TREE_IMAGPART (exp), thissize / 2,
3992 min_align (align, BITS_PER_UNIT * (thissize / 2)));
3997 if (TREE_CODE (exp) == CONSTRUCTOR)
3999 output_constructor (exp, size, align);
4002 else if (TREE_CODE (exp) == STRING_CST)
4004 thissize = MIN (TREE_STRING_LENGTH (exp), size);
4005 assemble_string (TREE_STRING_POINTER (exp), thissize);
4013 if (TREE_CODE (exp) == CONSTRUCTOR)
4014 output_constructor (exp, size, align);
4020 if (TREE_CODE (exp) == INTEGER_CST)
4021 assemble_integer (expand_expr (exp, NULL_RTX,
4022 VOIDmode, EXPAND_INITIALIZER),
4023 thissize, align, 1);
4024 else if (TREE_CODE (exp) == CONSTRUCTOR)
4026 unsigned char *buffer = (unsigned char *) alloca (thissize);
4027 if (get_set_constructor_bytes (exp, buffer, thissize))
4029 assemble_string ((char *) buffer, thissize);
4032 error ("unknown set constructor type");
4044 assemble_zeros (size);
4048 /* Subroutine of output_constructor, used for computing the size of
4049 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
4050 type with an unspecified upper bound. */
4052 static unsigned HOST_WIDE_INT
4053 array_size_for_constructor (val)
4058 /* This code used to attempt to handle string constants that are not
4059 arrays of single-bytes, but nothing else does, so there's no point in
4061 if (TREE_CODE (val) == STRING_CST)
4062 return TREE_STRING_LENGTH (val);
4064 max_index = NULL_TREE;
4065 for (i = CONSTRUCTOR_ELTS (val); i; i = TREE_CHAIN (i))
4067 tree index = TREE_PURPOSE (i);
4069 if (TREE_CODE (index) == RANGE_EXPR)
4070 index = TREE_OPERAND (index, 1);
4071 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
4075 if (max_index == NULL_TREE)
4078 /* Compute the total number of array elements. */
4079 i = size_binop (MINUS_EXPR, convert (sizetype, max_index),
4081 TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)))));
4082 i = size_binop (PLUS_EXPR, i, convert (sizetype, integer_one_node));
4084 /* Multiply by the array element unit size to find number of bytes. */
4085 i = size_binop (MULT_EXPR, i, TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
4087 return tree_low_cst (i, 1);
4090 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
4091 Generate at least SIZE bytes, padding if necessary. */
4094 output_constructor (exp, size, align)
4099 tree type = TREE_TYPE (exp);
4100 tree link, field = 0;
4102 /* Number of bytes output or skipped so far.
4103 In other words, current position within the constructor. */
4104 HOST_WIDE_INT total_bytes = 0;
4105 /* Non-zero means BYTE contains part of a byte, to be output. */
4106 int byte_buffer_in_use = 0;
4109 if (HOST_BITS_PER_WIDE_INT < BITS_PER_UNIT)
4112 if (TREE_CODE (type) == RECORD_TYPE)
4113 field = TYPE_FIELDS (type);
4115 if (TREE_CODE (type) == ARRAY_TYPE
4116 && TYPE_DOMAIN (type) != 0)
4117 min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (type));
4119 /* As LINK goes through the elements of the constant,
4120 FIELD goes through the structure fields, if the constant is a structure.
4121 if the constant is a union, then we override this,
4122 by getting the field from the TREE_LIST element.
4123 But the constant could also be an array. Then FIELD is zero.
4125 There is always a maximum of one element in the chain LINK for unions
4126 (even if the initializer in a source program incorrectly contains
4128 for (link = CONSTRUCTOR_ELTS (exp);
4130 link = TREE_CHAIN (link),
4131 field = field ? TREE_CHAIN (field) : 0)
4133 tree val = TREE_VALUE (link);
4136 /* The element in a union constructor specifies the proper field
4138 if ((TREE_CODE (type) == RECORD_TYPE || TREE_CODE (type) == UNION_TYPE
4139 || TREE_CODE (type) == QUAL_UNION_TYPE)
4140 && TREE_PURPOSE (link) != 0)
4141 field = TREE_PURPOSE (link);
4143 else if (TREE_CODE (type) == ARRAY_TYPE)
4144 index = TREE_PURPOSE (link);
4146 /* Eliminate the marker that makes a cast not be an lvalue. */
4150 if (index && TREE_CODE (index) == RANGE_EXPR)
4152 unsigned HOST_WIDE_INT fieldsize
4153 = int_size_in_bytes (TREE_TYPE (type));
4154 HOST_WIDE_INT lo_index = tree_low_cst (TREE_OPERAND (index, 0), 0);
4155 HOST_WIDE_INT hi_index = tree_low_cst (TREE_OPERAND (index, 1), 0);
4156 HOST_WIDE_INT index;
4157 unsigned int align2 = min_align (align, fieldsize * BITS_PER_UNIT);
4159 for (index = lo_index; index <= hi_index; index++)
4161 /* Output the element's initial value. */
4163 assemble_zeros (fieldsize);
4165 output_constant (val, fieldsize, align2);
4167 /* Count its size. */
4168 total_bytes += fieldsize;
4171 else if (field == 0 || !DECL_BIT_FIELD (field))
4173 /* An element that is not a bit-field. */
4175 unsigned HOST_WIDE_INT fieldsize;
4176 /* Since this structure is static,
4177 we know the positions are constant. */
4178 HOST_WIDE_INT pos = field ? int_byte_position (field) : 0;
4179 unsigned int align2;
4182 pos = (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (val)), 1)
4183 * (tree_low_cst (index, 0) - tree_low_cst (min_index, 0)));
4185 /* Output any buffered-up bit-fields preceding this element. */
4186 if (byte_buffer_in_use)
4188 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4190 byte_buffer_in_use = 0;
4193 /* Advance to offset of this element.
4194 Note no alignment needed in an array, since that is guaranteed
4195 if each element has the proper size. */
4196 if ((field != 0 || index != 0) && pos != total_bytes)
4198 assemble_zeros (pos - total_bytes);
4202 /* Find the alignment of this element. */
4203 align2 = min_align (align, BITS_PER_UNIT * pos);
4205 /* Determine size this element should occupy. */
4210 /* If this is an array with an unspecified upper bound,
4211 the initializer determines the size. */
4212 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
4213 but we cannot do this until the deprecated support for
4214 initializing zero-length array members is removed. */
4215 if (TREE_CODE (TREE_TYPE (field)) == ARRAY_TYPE
4216 && TYPE_DOMAIN (TREE_TYPE (field))
4217 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (field))))
4219 fieldsize = array_size_for_constructor (val);
4220 /* Given a non-empty initialization, this field had
4222 if (fieldsize != 0 && TREE_CHAIN (field) != NULL_TREE)
4225 else if (DECL_SIZE_UNIT (field))
4227 /* ??? This can't be right. If the decl size overflows
4228 a host integer we will silently emit no data. */
4229 if (host_integerp (DECL_SIZE_UNIT (field), 1))
4230 fieldsize = tree_low_cst (DECL_SIZE_UNIT (field), 1);
4234 fieldsize = int_size_in_bytes (TREE_TYPE (type));
4236 /* Output the element's initial value. */
4238 assemble_zeros (fieldsize);
4240 output_constant (val, fieldsize, align2);
4242 /* Count its size. */
4243 total_bytes += fieldsize;
4245 else if (val != 0 && TREE_CODE (val) != INTEGER_CST)
4246 error ("invalid initial value for member `%s'",
4247 IDENTIFIER_POINTER (DECL_NAME (field)));
4250 /* Element that is a bit-field. */
4252 HOST_WIDE_INT next_offset = int_bit_position (field);
4253 HOST_WIDE_INT end_offset
4254 = (next_offset + tree_low_cst (DECL_SIZE (field), 1));
4257 val = integer_zero_node;
4259 /* If this field does not start in this (or, next) byte,
4261 if (next_offset / BITS_PER_UNIT != total_bytes)
4263 /* Output remnant of any bit field in previous bytes. */
4264 if (byte_buffer_in_use)
4266 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4268 byte_buffer_in_use = 0;
4271 /* If still not at proper byte, advance to there. */
4272 if (next_offset / BITS_PER_UNIT != total_bytes)
4274 assemble_zeros (next_offset / BITS_PER_UNIT - total_bytes);
4275 total_bytes = next_offset / BITS_PER_UNIT;
4279 if (! byte_buffer_in_use)
4282 /* We must split the element into pieces that fall within
4283 separate bytes, and combine each byte with previous or
4284 following bit-fields. */
4286 /* next_offset is the offset n fbits from the beginning of
4287 the structure to the next bit of this element to be processed.
4288 end_offset is the offset of the first bit past the end of
4290 while (next_offset < end_offset)
4294 HOST_WIDE_INT value;
4295 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
4296 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
4298 /* Advance from byte to byte
4299 within this element when necessary. */
4300 while (next_byte != total_bytes)
4302 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4307 /* Number of bits we can process at once
4308 (all part of the same byte). */
4309 this_time = MIN (end_offset - next_offset,
4310 BITS_PER_UNIT - next_bit);
4311 if (BYTES_BIG_ENDIAN)
4313 /* On big-endian machine, take the most significant bits
4314 first (of the bits that are significant)
4315 and put them into bytes from the most significant end. */
4316 shift = end_offset - next_offset - this_time;
4318 /* Don't try to take a bunch of bits that cross
4319 the word boundary in the INTEGER_CST. We can
4320 only select bits from the LOW or HIGH part
4322 if (shift < HOST_BITS_PER_WIDE_INT
4323 && shift + this_time > HOST_BITS_PER_WIDE_INT)
4325 this_time = shift + this_time - HOST_BITS_PER_WIDE_INT;
4326 shift = HOST_BITS_PER_WIDE_INT;
4329 /* Now get the bits from the appropriate constant word. */
4330 if (shift < HOST_BITS_PER_WIDE_INT)
4331 value = TREE_INT_CST_LOW (val);
4332 else if (shift < 2 * HOST_BITS_PER_WIDE_INT)
4334 value = TREE_INT_CST_HIGH (val);
4335 shift -= HOST_BITS_PER_WIDE_INT;
4340 /* Get the result. This works only when:
4341 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
4342 byte |= (((value >> shift)
4343 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
4344 << (BITS_PER_UNIT - this_time - next_bit));
4348 /* On little-endian machines,
4349 take first the least significant bits of the value
4350 and pack them starting at the least significant
4351 bits of the bytes. */
4352 shift = next_offset - int_bit_position (field);
4354 /* Don't try to take a bunch of bits that cross
4355 the word boundary in the INTEGER_CST. We can
4356 only select bits from the LOW or HIGH part
4358 if (shift < HOST_BITS_PER_WIDE_INT
4359 && shift + this_time > HOST_BITS_PER_WIDE_INT)
4360 this_time = (HOST_BITS_PER_WIDE_INT - shift);
4362 /* Now get the bits from the appropriate constant word. */
4363 if (shift < HOST_BITS_PER_WIDE_INT)
4364 value = TREE_INT_CST_LOW (val);
4365 else if (shift < 2 * HOST_BITS_PER_WIDE_INT)
4367 value = TREE_INT_CST_HIGH (val);
4368 shift -= HOST_BITS_PER_WIDE_INT;
4373 /* Get the result. This works only when:
4374 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
4375 byte |= (((value >> shift)
4376 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
4380 next_offset += this_time;
4381 byte_buffer_in_use = 1;
4386 if (byte_buffer_in_use)
4388 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4392 if (total_bytes < size)
4393 assemble_zeros (size - total_bytes);
4396 /* This TREE_LIST contains any weak symbol declarations waiting
4398 static GTY(()) tree weak_decls;
4400 /* Mark DECL as weak. */
4406 DECL_WEAK (decl) = 1;
4408 if (DECL_RTL_SET_P (decl)
4409 && GET_CODE (DECL_RTL (decl)) == MEM
4410 && XEXP (DECL_RTL (decl), 0)
4411 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
4412 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
4415 /* Merge weak status between NEWDECL and OLDDECL. */
4418 merge_weak (newdecl, olddecl)
4422 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
4425 if (DECL_WEAK (newdecl))
4429 /* NEWDECL is weak, but OLDDECL is not. */
4431 /* If we already output the OLDDECL, we're in trouble; we can't
4432 go back and make it weak. This error cannot caught in
4433 declare_weak because the NEWDECL and OLDDECL was not yet
4434 been merged; therefore, TREE_ASM_WRITTEN was not set. */
4435 if (TREE_ASM_WRITTEN (olddecl))
4436 error_with_decl (newdecl,
4437 "weak declaration of `%s' must precede definition");
4439 /* If we've already generated rtl referencing OLDDECL, we may
4440 have done so in a way that will not function properly with
4442 else if (TREE_USED (olddecl)
4443 && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)))
4444 warning_with_decl (newdecl, "weak declaration of `%s' after first use results in unspecified behavior");
4448 /* We put the NEWDECL on the weak_decls list at some point.
4449 Replace it with the OLDDECL. */
4450 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
4451 if (TREE_VALUE (wd) == newdecl)
4453 TREE_VALUE (wd) = olddecl;
4456 /* We may not find the entry on the list. If NEWDECL is a
4457 weak alias, then we will have already called
4458 globalize_decl to remove the entry; in that case, we do
4459 not need to do anything. */
4462 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
4463 mark_weak (olddecl);
4466 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
4467 weak. Just update NEWDECL to indicate that it's weak too. */
4468 mark_weak (newdecl);
4471 /* Declare DECL to be a weak symbol. */
4477 if (! TREE_PUBLIC (decl))
4478 error_with_decl (decl, "weak declaration of `%s' must be public");
4479 else if (TREE_CODE (decl) == FUNCTION_DECL && TREE_ASM_WRITTEN (decl))
4480 error_with_decl (decl, "weak declaration of `%s' must precede definition");
4481 else if (SUPPORTS_WEAK)
4483 if (! DECL_WEAK (decl))
4484 weak_decls = tree_cons (NULL, decl, weak_decls);
4487 warning_with_decl (decl, "weak declaration of `%s' not supported");
4492 /* Emit any pending weak declarations. */
4499 for (t = weak_decls; t; t = TREE_CHAIN (t))
4501 tree decl = TREE_VALUE (t);
4502 const char *name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
4504 if (! TREE_USED (decl))
4507 #ifdef ASM_WEAKEN_DECL
4508 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
4510 #ifdef ASM_WEAKEN_LABEL
4511 ASM_WEAKEN_LABEL (asm_out_file, name);
4513 #ifdef ASM_OUTPUT_WEAK_ALIAS
4514 warning ("only weak aliases are supported in this configuration");
4522 /* Emit the assembly bits to indicate that DECL is globally visible. */
4525 globalize_decl (decl)
4528 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
4530 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
4531 if (DECL_WEAK (decl))
4535 #ifdef ASM_WEAKEN_DECL
4536 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
4538 ASM_WEAKEN_LABEL (asm_out_file, name);
4541 /* Remove this function from the pending weak list so that
4542 we do not emit multiple .weak directives for it. */
4543 for (p = &weak_decls; (t = *p) ; )
4545 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
4546 *p = TREE_CHAIN (t);
4548 p = &TREE_CHAIN (t);
4554 ASM_GLOBALIZE_LABEL (asm_out_file, name);
4557 /* Emit an assembler directive to make the symbol for DECL an alias to
4558 the symbol for TARGET. */
4561 assemble_alias (decl, target)
4562 tree decl, target ATTRIBUTE_UNUSED;
4566 /* We must force creation of DECL_RTL for debug info generation, even though
4567 we don't use it here. */
4568 make_decl_rtl (decl, NULL);
4570 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
4572 #ifdef ASM_OUTPUT_DEF
4573 /* Make name accessible from other files, if appropriate. */
4575 if (TREE_PUBLIC (decl))
4577 globalize_decl (decl);
4578 maybe_assemble_visibility (decl);
4581 #ifdef ASM_OUTPUT_DEF_FROM_DECLS
4582 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
4584 ASM_OUTPUT_DEF (asm_out_file, name, IDENTIFIER_POINTER (target));
4586 #else /* !ASM_OUTPUT_DEF */
4587 #if defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
4588 if (! DECL_WEAK (decl))
4589 warning ("only weak aliases are supported in this configuration");
4591 #ifdef ASM_WEAKEN_DECL
4592 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
4594 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
4597 warning ("alias definitions not supported in this configuration; ignored");
4601 TREE_USED (decl) = 1;
4602 TREE_ASM_WRITTEN (decl) = 1;
4603 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
4606 /* Emit an assembler directive to set symbol for DECL visibility to
4610 assemble_visibility (decl, visibility_type)
4612 const char *visibility_type ATTRIBUTE_UNUSED;
4616 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
4618 #ifdef HAVE_GAS_HIDDEN
4619 fprintf (asm_out_file, "\t.%s\t%s\n", visibility_type, name);
4621 warning ("visibility attribute not supported in this configuration; ignored");
4625 /* A helper function to call assemble_visibility when needed for a decl. */
4628 maybe_assemble_visibility (decl)
4631 tree visibility = lookup_attribute ("visibility", DECL_ATTRIBUTES (decl));
4635 = TREE_STRING_POINTER (TREE_VALUE (TREE_VALUE (visibility)));
4636 assemble_visibility (decl, type);
4640 /* Returns 1 if the target configuration supports defining public symbols
4641 so that one of them will be chosen at link time instead of generating a
4642 multiply-defined symbol error, whether through the use of weak symbols or
4643 a target-specific mechanism for having duplicates discarded. */
4646 supports_one_only ()
4648 if (SUPPORTS_ONE_ONLY)
4650 return SUPPORTS_WEAK;
4653 /* Set up DECL as a public symbol that can be defined in multiple
4654 translation units without generating a linker error. */
4657 make_decl_one_only (decl)
4660 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != FUNCTION_DECL)
4663 TREE_PUBLIC (decl) = 1;
4665 if (TREE_CODE (decl) == VAR_DECL
4666 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node))
4667 DECL_COMMON (decl) = 1;
4668 else if (SUPPORTS_ONE_ONLY)
4670 #ifdef MAKE_DECL_ONE_ONLY
4671 MAKE_DECL_ONE_ONLY (decl);
4673 DECL_ONE_ONLY (decl) = 1;
4675 else if (SUPPORTS_WEAK)
4676 DECL_WEAK (decl) = 1;
4684 const_str_htab = htab_create_ggc (128, const_str_htab_hash,
4685 const_str_htab_eq, NULL);
4686 in_named_htab = htab_create (31, in_named_entry_hash,
4687 in_named_entry_eq, NULL);
4689 const_alias_set = new_alias_set ();
4692 /* Select a set of attributes for section NAME based on the properties
4693 of DECL and whether or not RELOC indicates that DECL's initializer
4694 might contain runtime relocations.
4696 We make the section read-only and executable for a function decl,
4697 read-only for a const data decl, and writable for a non-const data decl. */
4700 default_section_type_flags (decl, name, reloc)
4707 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
4708 flags = SECTION_CODE;
4709 else if (decl && DECL_READONLY_SECTION (decl, reloc))
4712 flags = SECTION_WRITE;
4714 if (decl && DECL_ONE_ONLY (decl))
4715 flags |= SECTION_LINKONCE;
4717 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl))
4718 flags |= SECTION_TLS | SECTION_WRITE;
4720 if (strcmp (name, ".bss") == 0
4721 || strncmp (name, ".bss.", 5) == 0
4722 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
4723 || strcmp (name, ".sbss") == 0
4724 || strncmp (name, ".sbss.", 6) == 0
4725 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0
4726 || strcmp (name, ".tbss") == 0
4727 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
4728 flags |= SECTION_BSS;
4730 if (strcmp (name, ".tdata") == 0
4731 || strcmp (name, ".tbss") == 0
4732 || strncmp (name, ".gnu.linkonce.td.", 17) == 0
4733 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
4734 flags |= SECTION_TLS;
4739 /* Output assembly to switch to section NAME with attribute FLAGS.
4740 Four variants for common object file formats. */
4743 default_no_named_section (name, flags)
4744 const char *name ATTRIBUTE_UNUSED;
4745 unsigned int flags ATTRIBUTE_UNUSED;
4747 /* Some object formats don't support named sections at all. The
4748 front-end should already have flagged this as an error. */
4753 default_elf_asm_named_section (name, flags)
4757 char flagchars[10], *f = flagchars;
4760 if (! named_section_first_declaration (name))
4762 fprintf (asm_out_file, "\t.section\t%s\n", name);
4766 if (!(flags & SECTION_DEBUG))
4768 if (flags & SECTION_WRITE)
4770 if (flags & SECTION_CODE)
4772 if (flags & SECTION_SMALL)
4774 if (flags & SECTION_MERGE)
4776 if (flags & SECTION_STRINGS)
4778 if (flags & SECTION_TLS)
4782 if (flags & SECTION_BSS)
4787 if (flags & SECTION_ENTSIZE)
4788 fprintf (asm_out_file, "\t.section\t%s,\"%s\",@%s,%d\n",
4789 name, flagchars, type, flags & SECTION_ENTSIZE);
4791 fprintf (asm_out_file, "\t.section\t%s,\"%s\",@%s\n",
4792 name, flagchars, type);
4796 default_coff_asm_named_section (name, flags)
4800 char flagchars[8], *f = flagchars;
4802 if (flags & SECTION_WRITE)
4804 if (flags & SECTION_CODE)
4808 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
4812 default_pe_asm_named_section (name, flags)
4816 default_coff_asm_named_section (name, flags);
4818 if (flags & SECTION_LINKONCE)
4820 /* Functions may have been compiled at various levels of
4821 optimization so we can't use `same_size' here.
4822 Instead, have the linker pick one. */
4823 fprintf (asm_out_file, "\t.linkonce %s\n",
4824 (flags & SECTION_CODE ? "discard" : "same_size"));
4828 /* Used for vtable gc in GNU binutils. Record that the pointer at OFFSET
4829 from SYMBOL is used in all classes derived from SYMBOL. */
4832 assemble_vtable_entry (symbol, offset)
4834 HOST_WIDE_INT offset;
4836 fputs ("\t.vtable_entry ", asm_out_file);
4837 output_addr_const (asm_out_file, symbol);
4838 fputs (", ", asm_out_file);
4839 fprintf (asm_out_file, HOST_WIDE_INT_PRINT_DEC, offset);
4840 fputc ('\n', asm_out_file);
4843 /* Used for vtable gc in GNU binutils. Record the class hierarchy by noting
4844 that the vtable symbol CHILD is derived from the vtable symbol PARENT. */
4847 assemble_vtable_inherit (child, parent)
4850 fputs ("\t.vtable_inherit ", asm_out_file);
4851 output_addr_const (asm_out_file, child);
4852 fputs (", ", asm_out_file);
4853 output_addr_const (asm_out_file, parent);
4854 fputc ('\n', asm_out_file);
4857 /* The lame default section selector. */
4860 default_select_section (decl, reloc, align)
4863 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED;
4865 bool readonly = false;
4869 if (DECL_READONLY_SECTION (decl, reloc))
4872 else if (TREE_CODE (decl) == CONSTRUCTOR)
4874 if (! ((flag_pic && reloc)
4875 || !TREE_READONLY (decl)
4876 || TREE_SIDE_EFFECTS (decl)
4877 || !TREE_CONSTANT (decl)))
4880 else if (TREE_CODE (decl) == STRING_CST)
4881 readonly = !flag_writable_strings;
4882 else if (! (flag_pic && reloc))
4886 readonly_data_section ();
4891 /* A helper function for default_elf_select_section and
4892 default_elf_unique_section. Categorizes the DECL. */
4894 enum section_category
4899 SECCAT_RODATA_MERGE_STR,
4900 SECCAT_RODATA_MERGE_STR_INIT,
4901 SECCAT_RODATA_MERGE_CONST,
4905 /* To optimize loading of shared programs, define following subsections
4907 _REL Contains data that has relocations, so they get grouped
4908 together and dynamic linker will visit fewer pages in memory.
4909 _RO Contains data that is otherwise read-only. This is useful
4910 with prelinking as most relocations won't be dynamically
4911 linked and thus stay read only.
4912 _LOCAL Marks data containing relocations only to local objects.
4913 These relocations will get fully resolved by prelinking. */
4915 SECCAT_DATA_REL_LOCAL,
4917 SECCAT_DATA_REL_RO_LOCAL,
4927 static enum section_category categorize_decl_for_section PARAMS ((tree, int));
4929 static enum section_category
4930 categorize_decl_for_section (decl, reloc)
4934 enum section_category ret;
4936 if (TREE_CODE (decl) == FUNCTION_DECL)
4938 else if (TREE_CODE (decl) == STRING_CST)
4940 if (flag_writable_strings)
4943 return SECCAT_RODATA_MERGE_STR;
4945 else if (TREE_CODE (decl) == VAR_DECL)
4947 if (DECL_INITIAL (decl) == NULL
4948 || DECL_INITIAL (decl) == error_mark_node)
4950 else if (! TREE_READONLY (decl)
4951 || TREE_SIDE_EFFECTS (decl)
4952 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
4954 if (flag_pic && (reloc & 2))
4955 ret = SECCAT_DATA_REL;
4956 else if (flag_pic && reloc)
4957 ret = SECCAT_DATA_REL_LOCAL;
4961 else if (flag_pic && (reloc & 2))
4962 ret = SECCAT_DATA_REL_RO;
4963 else if (flag_pic && reloc)
4964 ret = SECCAT_DATA_REL_RO_LOCAL;
4965 else if (flag_merge_constants < 2)
4966 /* C and C++ don't allow different variables to share the same
4967 location. -fmerge-all-constants allows even that (at the
4968 expense of not conforming). */
4969 ret = SECCAT_RODATA;
4970 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
4971 ret = SECCAT_RODATA_MERGE_STR_INIT;
4973 ret = SECCAT_RODATA_MERGE_CONST;
4975 else if (TREE_CODE (decl) == CONSTRUCTOR)
4977 if ((flag_pic && reloc)
4978 || TREE_SIDE_EFFECTS (decl)
4979 || ! TREE_CONSTANT (decl))
4982 ret = SECCAT_RODATA;
4985 ret = SECCAT_RODATA;
4987 /* There are no read-only thread-local sections. */
4988 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl))
4990 if (ret == SECCAT_BSS)
4996 /* If the target uses small data sections, select it. */
4997 else if ((*targetm.in_small_data_p) (decl))
4999 if (ret == SECCAT_BSS)
5008 /* Select a section based on the above categorization. */
5011 default_elf_select_section (decl, reloc, align)
5014 unsigned HOST_WIDE_INT align;
5016 switch (categorize_decl_for_section (decl, reloc))
5019 /* We're not supposed to be called on FUNCTION_DECLs. */
5022 readonly_data_section ();
5024 case SECCAT_RODATA_MERGE_STR:
5025 mergeable_string_section (decl, align, 0);
5027 case SECCAT_RODATA_MERGE_STR_INIT:
5028 mergeable_string_section (DECL_INITIAL (decl), align, 0);
5030 case SECCAT_RODATA_MERGE_CONST:
5031 mergeable_constant_section (DECL_MODE (decl), align, 0);
5036 case SECCAT_DATA_REL:
5037 named_section (NULL_TREE, ".data.rel", reloc);
5039 case SECCAT_DATA_REL_LOCAL:
5040 named_section (NULL_TREE, ".data.rel.local", reloc);
5042 case SECCAT_DATA_REL_RO:
5043 named_section (NULL_TREE, ".data.rel.ro", reloc);
5045 case SECCAT_DATA_REL_RO_LOCAL:
5046 named_section (NULL_TREE, ".data.rel.ro.local", reloc);
5049 named_section (NULL_TREE, ".sdata", reloc);
5052 named_section (NULL_TREE, ".tdata", reloc);
5055 #ifdef BSS_SECTION_ASM_OP
5058 named_section (NULL_TREE, ".bss", reloc);
5062 named_section (NULL_TREE, ".sbss", reloc);
5065 named_section (NULL_TREE, ".tbss", reloc);
5072 /* Construct a unique section name based on the decl name and the
5073 categorization performed above. */
5076 default_unique_section (decl, reloc)
5080 bool one_only = DECL_ONE_ONLY (decl);
5081 const char *prefix, *name;
5085 switch (categorize_decl_for_section (decl, reloc))
5088 prefix = one_only ? ".gnu.linkonce.t." : ".text.";
5091 case SECCAT_RODATA_MERGE_STR:
5092 case SECCAT_RODATA_MERGE_STR_INIT:
5093 case SECCAT_RODATA_MERGE_CONST:
5094 prefix = one_only ? ".gnu.linkonce.r." : ".rodata.";
5097 case SECCAT_DATA_REL:
5098 case SECCAT_DATA_REL_LOCAL:
5099 case SECCAT_DATA_REL_RO:
5100 case SECCAT_DATA_REL_RO_LOCAL:
5101 prefix = one_only ? ".gnu.linkonce.d." : ".data.";
5104 prefix = one_only ? ".gnu.linkonce.s." : ".sdata.";
5107 prefix = one_only ? ".gnu.linkonce.b." : ".bss.";
5110 prefix = one_only ? ".gnu.linkonce.sb." : ".sbss.";
5113 prefix = one_only ? ".gnu.linkonce.td." : ".tdata.";
5116 prefix = one_only ? ".gnu.linkonce.tb." : ".tbss.";
5121 plen = strlen (prefix);
5123 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
5124 name = (* targetm.strip_name_encoding) (name);
5125 nlen = strlen (name);
5127 string = alloca (nlen + plen + 1);
5128 memcpy (string, prefix, plen);
5129 memcpy (string + plen, name, nlen + 1);
5131 DECL_SECTION_NAME (decl) = build_string (nlen + plen, string);
5135 default_select_rtx_section (mode, x, align)
5136 enum machine_mode mode ATTRIBUTE_UNUSED;
5138 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED;
5141 switch (GET_CODE (x))
5153 readonly_data_section ();
5157 default_elf_select_rtx_section (mode, x, align)
5158 enum machine_mode mode;
5160 unsigned HOST_WIDE_INT align;
5162 /* ??? Handle small data here somehow. */
5165 switch (GET_CODE (x))
5169 named_section (NULL_TREE, ".data.rel.ro", 3);
5173 named_section (NULL_TREE, ".data.rel.ro.local", 1);
5180 mergeable_constant_section (mode, align, 0);
5183 /* By default, we do nothing for encode_section_info, so we need not
5184 do anything but discard the '*' marker. */
5187 default_strip_name_encoding (str)
5190 return str + (*str == '*');
5193 /* Assume ELF-ish defaults, since that's pretty much the most liberal
5194 wrt cross-module name binding. */
5197 default_binds_local_p (exp)
5202 /* A non-decl is an entry in the constant pool. */
5205 /* Static variables are always local. */
5206 else if (! TREE_PUBLIC (exp))
5208 /* A variable is local if the user tells us so. */
5209 else if (MODULE_LOCAL_P (exp))
5211 /* Otherwise, variables defined outside this object may not be local. */
5212 else if (DECL_EXTERNAL (exp))
5214 /* Linkonce and weak data are never local. */
5215 else if (DECL_ONE_ONLY (exp) || DECL_WEAK (exp))
5217 /* If PIC, then assume that any global name can be overridden by
5218 symbols resolved from other modules. */
5221 /* Uninitialized COMMON variable may be unified with symbols
5222 resolved from other modules. */
5223 else if (DECL_COMMON (exp)
5224 && (DECL_INITIAL (exp) == NULL
5225 || DECL_INITIAL (exp) == error_mark_node))
5227 /* Otherwise we're left with initialized (or non-common) global data
5228 which is of necessity defined locally. */
5235 #include "gt-varasm.h"