1 /* Output variables, constants and external declarations, for GNU compiler.
2 Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
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. */
32 #include "coretypes.h"
39 #include "hard-reg-set.h"
47 #include "langhooks.h"
51 #include "tree-mudflap.h"
53 #include "cfglayout.h"
55 #ifdef XCOFF_DEBUGGING_INFO
56 #include "xcoffout.h" /* Needed for external data
57 declarations for e.g. AIX 4.x. */
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;
70 struct rtx_constant_pool;
72 struct varasm_status GTY(())
74 /* If we're using a per-function constant pool, this is it. */
75 struct rtx_constant_pool *pool;
77 /* Number of tree-constants deferred during the expansion of this
79 unsigned int deferred_constants;
82 #define n_deferred_constants (cfun->varasm->deferred_constants)
84 /* Number for making the label on the next
85 constant that is stored in memory. */
87 static GTY(()) int const_labelno;
89 /* Carry information from ASM_DECLARE_OBJECT_NAME
90 to ASM_FINISH_DECLARE_OBJECT. */
92 int size_directive_output;
94 /* The last decl for which assemble_variable was called,
95 if it did ASM_DECLARE_OBJECT_NAME.
96 If the last call to assemble_variable didn't do that,
99 tree last_assemble_variable_decl;
101 /* The following global variable indicates if the section label for the
102 "cold" section of code has been output yet to the assembler. The
103 label is useful when running gdb. This is part of the optimization that
104 partitions hot and cold basic blocks into separate sections of the .o
107 bool unlikely_section_label_printed = false;
109 /* The following global variable indicates the label name to be put at
110 the start of the first cold section within each function, when
111 partitioning basic blocks into hot and cold sections. */
113 char *unlikely_section_label = NULL;
115 /* The following global variable indicates the section name to be used
116 for the current cold section, when partitioning hot and cold basic
117 blocks into separate sections. */
119 char *unlikely_text_section_name = NULL;
121 /* RTX_UNCHANGING_P in a MEM can mean it is stored into, for initialization.
122 So giving constant the alias set for the type will allow such
123 initializations to appear to conflict with the load of the constant. We
124 avoid this by giving all constants an alias set for just constants.
125 Since there will be no stores to that alias set, nothing will ever
126 conflict with them. */
128 static HOST_WIDE_INT const_alias_set;
130 static const char *strip_reg_name (const char *);
131 static int contains_pointers_p (tree);
132 #ifdef ASM_OUTPUT_EXTERNAL
133 static bool incorporeal_function_p (tree);
135 static void decode_addr_const (tree, struct addr_const *);
136 static hashval_t const_desc_hash (const void *);
137 static int const_desc_eq (const void *, const void *);
138 static hashval_t const_hash_1 (const tree);
139 static int compare_constant (const tree, const tree);
140 static tree copy_constant (tree);
141 static void output_constant_def_contents (rtx);
142 static void output_addressed_constants (tree);
143 static unsigned HOST_WIDE_INT array_size_for_constructor (tree);
144 static unsigned min_align (unsigned, unsigned);
145 static void output_constructor (tree, unsigned HOST_WIDE_INT, unsigned int);
146 static void globalize_decl (tree);
147 static void maybe_assemble_visibility (tree);
148 static int in_named_entry_eq (const void *, const void *);
149 static hashval_t in_named_entry_hash (const void *);
150 #ifdef BSS_SECTION_ASM_OP
151 #ifdef ASM_OUTPUT_BSS
152 static void asm_output_bss (FILE *, tree, const char *,
153 unsigned HOST_WIDE_INT, unsigned HOST_WIDE_INT);
155 #ifdef ASM_OUTPUT_ALIGNED_BSS
156 static void asm_output_aligned_bss (FILE *, tree, const char *,
157 unsigned HOST_WIDE_INT, int)
160 #endif /* BSS_SECTION_ASM_OP */
161 static bool asm_emit_uninitialised (tree, const char*,
162 unsigned HOST_WIDE_INT,
163 unsigned HOST_WIDE_INT);
164 static void mark_weak (tree);
166 enum in_section { no_section, in_text, in_unlikely_executed_text, in_data,
168 #ifdef BSS_SECTION_ASM_OP
171 #ifdef CTORS_SECTION_ASM_OP
174 #ifdef DTORS_SECTION_ASM_OP
177 #ifdef READONLY_DATA_SECTION_ASM_OP
180 #ifdef EXTRA_SECTIONS
184 static GTY(()) enum in_section in_section = no_section;
186 /* Return a nonzero value if DECL has a section attribute. */
187 #ifndef IN_NAMED_SECTION
188 #define IN_NAMED_SECTION(DECL) \
189 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \
190 && DECL_SECTION_NAME (DECL) != NULL_TREE)
193 /* Text of section name when in_section == in_named. */
194 static GTY(()) const char *in_named_name;
196 /* Hash table of flags that have been used for a particular named section. */
198 struct in_named_entry GTY(())
205 static GTY((param_is (struct in_named_entry))) htab_t in_named_htab;
207 /* Define functions like text_section for any extra sections. */
208 #ifdef EXTRA_SECTION_FUNCTIONS
209 EXTRA_SECTION_FUNCTIONS
212 /* Tell assembler to switch to text section. */
217 if (in_section != in_text)
219 in_section = in_text;
220 fprintf (asm_out_file, "%s\n", TEXT_SECTION_ASM_OP);
224 /* Tell assembler to switch to unlikely-to-be-executed text section. */
227 unlikely_text_section (void)
229 if ((in_section != in_unlikely_executed_text)
230 && (in_section != in_named
231 || strcmp (in_named_name, UNLIKELY_EXECUTED_TEXT_SECTION_NAME) != 0))
233 if (targetm.have_named_sections)
234 named_section (NULL_TREE, UNLIKELY_EXECUTED_TEXT_SECTION_NAME, 0);
237 in_section = in_unlikely_executed_text;
238 fprintf (asm_out_file, "%s\n", TEXT_SECTION_ASM_OP);
241 if (!unlikely_section_label_printed)
243 ASM_OUTPUT_LABEL (asm_out_file, unlikely_section_label);
244 unlikely_section_label_printed = true;
249 /* Tell assembler to switch to data section. */
254 if (in_section != in_data)
256 in_section = in_data;
257 fprintf (asm_out_file, "%s\n", DATA_SECTION_ASM_OP);
261 /* Tell assembler to switch to read-only data section. This is normally
265 readonly_data_section (void)
267 #ifdef READONLY_DATA_SECTION
268 READONLY_DATA_SECTION (); /* Note this can call data_section. */
270 #ifdef READONLY_DATA_SECTION_ASM_OP
271 if (in_section != in_readonly_data)
273 in_section = in_readonly_data;
274 fputs (READONLY_DATA_SECTION_ASM_OP, asm_out_file);
275 fputc ('\n', asm_out_file);
283 /* Determine if we're in the text section. */
286 in_text_section (void)
288 return in_section == in_text;
291 /* Determine if we're in the unlikely-to-be-executed text section. */
294 in_unlikely_text_section (void)
296 return in_section == in_unlikely_executed_text;
299 /* Determine if we're in the data section. */
302 in_data_section (void)
304 return in_section == in_data;
307 /* Helper routines for maintaining in_named_htab. */
310 in_named_entry_eq (const void *p1, const void *p2)
312 const struct in_named_entry *old = p1;
313 const char *new = p2;
315 return strcmp (old->name, new) == 0;
319 in_named_entry_hash (const void *p)
321 const struct in_named_entry *old = p;
322 return htab_hash_string (old->name);
325 /* If SECTION has been seen before as a named section, return the flags
326 that were used. Otherwise, return 0. Note, that 0 is a perfectly valid
327 set of flags for a section to have, so 0 does not mean that the section
328 has not been seen. */
331 get_named_section_flags (const char *section)
333 struct in_named_entry **slot;
335 slot = (struct in_named_entry **)
336 htab_find_slot_with_hash (in_named_htab, section,
337 htab_hash_string (section), NO_INSERT);
339 return slot ? (*slot)->flags : 0;
342 /* Returns true if the section has been declared before. Sets internal
343 flag on this section in in_named_hash so subsequent calls on this
344 section will return false. */
347 named_section_first_declaration (const char *name)
349 struct in_named_entry **slot;
351 slot = (struct in_named_entry **)
352 htab_find_slot_with_hash (in_named_htab, name,
353 htab_hash_string (name), NO_INSERT);
354 if (! (*slot)->declared)
356 (*slot)->declared = true;
366 /* Record FLAGS for SECTION. If SECTION was previously recorded with a
367 different set of flags, return false. */
370 set_named_section_flags (const char *section, unsigned int flags)
372 struct in_named_entry **slot, *entry;
374 slot = (struct in_named_entry **)
375 htab_find_slot_with_hash (in_named_htab, section,
376 htab_hash_string (section), INSERT);
381 entry = ggc_alloc (sizeof (*entry));
383 entry->name = ggc_strdup (section);
384 entry->flags = flags;
385 entry->declared = false;
387 else if (entry->flags != flags)
393 /* Tell assembler to change to section NAME with attributes FLAGS. */
396 named_section_flags (const char *name, unsigned int flags)
398 if (in_section != in_named || strcmp (name, in_named_name) != 0)
400 if (! set_named_section_flags (name, flags))
403 targetm.asm_out.named_section (name, flags);
405 if (flags & SECTION_FORGET)
406 in_section = no_section;
409 in_named_name = ggc_strdup (name);
410 in_section = in_named;
415 /* Tell assembler to change to section NAME for DECL.
416 If DECL is NULL, just switch to section NAME.
417 If NAME is NULL, get the name from DECL.
418 If RELOC is 1, the initializer for DECL contains relocs. */
421 named_section (tree decl, const char *name, int reloc)
425 if (decl != NULL_TREE && !DECL_P (decl))
428 name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
430 flags = targetm.section_type_flags (decl, name, reloc);
432 /* Sanity check user variables for flag changes. Non-user
433 section flag changes will abort in named_section_flags.
434 However, don't complain if SECTION_OVERRIDE is set.
435 We trust that the setter knows that it is safe to ignore
436 the default flags for this decl. */
437 if (decl && ! set_named_section_flags (name, flags))
439 flags = get_named_section_flags (name);
440 if ((flags & SECTION_OVERRIDE) == 0)
441 error ("%J%D causes a section type conflict", decl, decl);
444 named_section_flags (name, flags);
447 /* If required, set DECL_SECTION_NAME to a unique name. */
450 resolve_unique_section (tree decl, int reloc ATTRIBUTE_UNUSED,
451 int flag_function_or_data_sections)
453 if (DECL_SECTION_NAME (decl) == NULL_TREE
454 && targetm.have_named_sections
455 && (flag_function_or_data_sections
456 || DECL_ONE_ONLY (decl)))
457 targetm.asm_out.unique_section (decl, reloc);
460 #ifdef BSS_SECTION_ASM_OP
462 /* Tell the assembler to switch to the bss section. */
467 if (in_section != in_bss)
469 fprintf (asm_out_file, "%s\n", BSS_SECTION_ASM_OP);
474 #ifdef ASM_OUTPUT_BSS
476 /* Utility function for ASM_OUTPUT_BSS for targets to use if
477 they don't support alignments in .bss.
478 ??? It is believed that this function will work in most cases so such
479 support is localized here. */
482 asm_output_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
484 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
485 unsigned HOST_WIDE_INT rounded)
487 targetm.asm_out.globalize_label (file, name);
489 #ifdef ASM_DECLARE_OBJECT_NAME
490 last_assemble_variable_decl = decl;
491 ASM_DECLARE_OBJECT_NAME (file, name, decl);
493 /* Standard thing is just output label for the object. */
494 ASM_OUTPUT_LABEL (file, name);
495 #endif /* ASM_DECLARE_OBJECT_NAME */
496 ASM_OUTPUT_SKIP (file, rounded ? rounded : 1);
501 #ifdef ASM_OUTPUT_ALIGNED_BSS
503 /* Utility function for targets to use in implementing
504 ASM_OUTPUT_ALIGNED_BSS.
505 ??? It is believed that this function will work in most cases so such
506 support is localized here. */
509 asm_output_aligned_bss (FILE *file, tree decl ATTRIBUTE_UNUSED,
510 const char *name, unsigned HOST_WIDE_INT size,
514 ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
515 #ifdef ASM_DECLARE_OBJECT_NAME
516 last_assemble_variable_decl = decl;
517 ASM_DECLARE_OBJECT_NAME (file, name, decl);
519 /* Standard thing is just output label for the object. */
520 ASM_OUTPUT_LABEL (file, name);
521 #endif /* ASM_DECLARE_OBJECT_NAME */
522 ASM_OUTPUT_SKIP (file, size ? size : 1);
527 #endif /* BSS_SECTION_ASM_OP */
529 /* Switch to the section for function DECL.
531 If DECL is NULL_TREE, switch to the text section.
532 ??? It's not clear that we will ever be passed NULL_TREE, but it's
533 safer to handle it. */
536 function_section (tree decl)
538 if (scan_ahead_for_unlikely_executed_note (get_insns()))
539 unlikely_text_section ();
542 if (decl != NULL_TREE
543 && DECL_SECTION_NAME (decl) != NULL_TREE)
544 named_section (decl, (char *) 0, 0);
550 /* Switch to read-only data section associated with function DECL. */
553 default_function_rodata_section (tree decl)
555 if (decl != NULL_TREE && DECL_SECTION_NAME (decl))
557 const char *name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
559 /* For .gnu.linkonce.t.foo we want to use .gnu.linkonce.r.foo. */
560 if (DECL_ONE_ONLY (decl) && strncmp (name, ".gnu.linkonce.t.", 16) == 0)
562 size_t len = strlen (name) + 1;
563 char *rname = alloca (len);
565 memcpy (rname, name, len);
567 named_section_flags (rname, SECTION_LINKONCE);
570 /* For .text.foo we want to use .rodata.foo. */
571 else if (flag_function_sections && flag_data_sections
572 && strncmp (name, ".text.", 6) == 0)
574 size_t len = strlen (name) + 1;
575 char *rname = alloca (len + 2);
577 memcpy (rname, ".rodata", 7);
578 memcpy (rname + 7, name + 5, len - 5);
579 named_section_flags (rname, 0);
584 readonly_data_section ();
587 /* Switch to read-only data section associated with function DECL
588 for targets where that section should be always the single
589 readonly data section. */
592 default_no_function_rodata_section (tree decl ATTRIBUTE_UNUSED)
594 readonly_data_section ();
597 /* Switch to section for variable DECL. RELOC is the same as the
598 argument to SELECT_SECTION. */
601 variable_section (tree decl, int reloc)
603 if (IN_NAMED_SECTION (decl))
604 named_section (decl, NULL, reloc);
606 targetm.asm_out.select_section (decl, reloc, DECL_ALIGN (decl));
609 /* Tell assembler to switch to the section for string merging. */
612 mergeable_string_section (tree decl ATTRIBUTE_UNUSED,
613 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
614 unsigned int flags ATTRIBUTE_UNUSED)
616 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
617 && TREE_CODE (decl) == STRING_CST
618 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
620 && TREE_STRING_LENGTH (decl) >= int_size_in_bytes (TREE_TYPE (decl)))
622 enum machine_mode mode;
623 unsigned int modesize;
628 mode = TYPE_MODE (TREE_TYPE (TREE_TYPE (decl)));
629 modesize = GET_MODE_BITSIZE (mode);
630 if (modesize >= 8 && modesize <= 256
631 && (modesize & (modesize - 1)) == 0)
633 if (align < modesize)
636 str = TREE_STRING_POINTER (decl);
637 len = TREE_STRING_LENGTH (decl);
638 unit = GET_MODE_SIZE (mode);
640 /* Check for embedded NUL characters. */
641 for (i = 0; i < len; i += unit)
643 for (j = 0; j < unit; j++)
644 if (str[i + j] != '\0')
651 sprintf (name, ".rodata.str%d.%d", modesize / 8,
653 flags |= (modesize / 8) | SECTION_MERGE | SECTION_STRINGS;
654 if (!i && modesize < align)
656 /* A "" string with requested alignment greater than
657 character size might cause a problem:
658 if some other string required even bigger
659 alignment than "", then linker might think the
660 "" is just part of padding after some other string
661 and not put it into the hash table initially.
662 But this means "" could have smaller alignment
664 #ifdef ASM_OUTPUT_SECTION_START
665 named_section_flags (name, flags);
666 ASM_OUTPUT_SECTION_START (asm_out_file);
668 readonly_data_section ();
673 named_section_flags (name, flags);
679 readonly_data_section ();
682 /* Tell assembler to switch to the section for constant merging. */
685 mergeable_constant_section (enum machine_mode mode ATTRIBUTE_UNUSED,
686 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED,
687 unsigned int flags ATTRIBUTE_UNUSED)
689 unsigned int modesize = GET_MODE_BITSIZE (mode);
691 if (HAVE_GAS_SHF_MERGE && flag_merge_constants
697 && (align & (align - 1)) == 0)
701 sprintf (name, ".rodata.cst%d", (int) (align / 8));
702 flags |= (align / 8) | SECTION_MERGE;
703 named_section_flags (name, flags);
707 readonly_data_section ();
710 /* Given NAME, a putative register name, discard any customary prefixes. */
713 strip_reg_name (const char *name)
715 #ifdef REGISTER_PREFIX
716 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
717 name += strlen (REGISTER_PREFIX);
719 if (name[0] == '%' || name[0] == '#')
724 /* The user has asked for a DECL to have a particular name. Set (or
725 change) it in such a way that we don't prefix an underscore to
728 set_user_assembler_name (tree decl, const char *name)
730 char *starred = alloca (strlen (name) + 2);
732 strcpy (starred + 1, name);
733 change_decl_assembler_name (decl, get_identifier (starred));
734 SET_DECL_RTL (decl, NULL_RTX);
737 /* Decode an `asm' spec for a declaration as a register name.
738 Return the register number, or -1 if nothing specified,
739 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
740 or -3 if ASMSPEC is `cc' and is not recognized,
741 or -4 if ASMSPEC is `memory' and is not recognized.
742 Accept an exact spelling or a decimal number.
743 Prefixes such as % are optional. */
746 decode_reg_name (const char *asmspec)
752 /* Get rid of confusing prefixes. */
753 asmspec = strip_reg_name (asmspec);
755 /* Allow a decimal number as a "register name". */
756 for (i = strlen (asmspec) - 1; i >= 0; i--)
757 if (! ISDIGIT (asmspec[i]))
759 if (asmspec[0] != 0 && i < 0)
762 if (i < FIRST_PSEUDO_REGISTER && i >= 0)
768 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
770 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
773 #ifdef ADDITIONAL_REGISTER_NAMES
775 static const struct { const char *const name; const int number; } table[]
776 = ADDITIONAL_REGISTER_NAMES;
778 for (i = 0; i < (int) ARRAY_SIZE (table); i++)
779 if (! strcmp (asmspec, table[i].name))
780 return table[i].number;
782 #endif /* ADDITIONAL_REGISTER_NAMES */
784 if (!strcmp (asmspec, "memory"))
787 if (!strcmp (asmspec, "cc"))
796 /* Create the DECL_RTL for a VAR_DECL or FUNCTION_DECL. DECL should
797 have static storage duration. In other words, it should not be an
798 automatic variable, including PARM_DECLs.
800 There is, however, one exception: this function handles variables
801 explicitly placed in a particular register by the user.
803 This is never called for PARM_DECL nodes. */
806 make_decl_rtl (tree decl)
808 const char *name = 0;
812 /* Check that we are not being given an automatic variable. */
813 /* A weak alias has TREE_PUBLIC set but not the other bits. */
814 if (TREE_CODE (decl) == PARM_DECL
815 || TREE_CODE (decl) == RESULT_DECL
816 || (TREE_CODE (decl) == VAR_DECL
817 && !TREE_STATIC (decl)
818 && !TREE_PUBLIC (decl)
819 && !DECL_EXTERNAL (decl)
820 && !DECL_REGISTER (decl)))
822 /* And that we were not given a type or a label. */
823 else if (TREE_CODE (decl) == TYPE_DECL
824 || TREE_CODE (decl) == LABEL_DECL)
827 /* For a duplicate declaration, we can be called twice on the
828 same DECL node. Don't discard the RTL already made. */
829 if (DECL_RTL_SET_P (decl))
831 /* If the old RTL had the wrong mode, fix the mode. */
832 if (GET_MODE (DECL_RTL (decl)) != DECL_MODE (decl))
833 SET_DECL_RTL (decl, adjust_address_nv (DECL_RTL (decl),
834 DECL_MODE (decl), 0));
836 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
839 /* ??? Another way to do this would be to maintain a hashed
840 table of such critters. Instead of adding stuff to a DECL
841 to give certain attributes to it, we could use an external
842 hash map from DECL to set of attributes. */
844 /* Let the target reassign the RTL if it wants.
845 This is necessary, for example, when one machine specific
846 decl attribute overrides another. */
847 targetm.encode_section_info (decl, DECL_RTL (decl), false);
849 /* Make this function static known to the mudflap runtime. */
850 if (flag_mudflap && TREE_CODE (decl) == VAR_DECL)
851 mudflap_enqueue_decl (decl);
856 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
858 reg_number = decode_reg_name (name);
860 if (TREE_CODE (decl) != FUNCTION_DECL && DECL_REGISTER (decl))
862 /* First detect errors in declaring global registers. */
863 if (reg_number == -1)
864 error ("%Jregister name not specified for '%D'", decl, decl);
865 else if (reg_number < 0)
866 error ("%Jinvalid register name for '%D'", decl, decl);
867 else if (TYPE_MODE (TREE_TYPE (decl)) == BLKmode)
868 error ("%Jdata type of '%D' isn't suitable for a register",
870 else if (! HARD_REGNO_MODE_OK (reg_number, TYPE_MODE (TREE_TYPE (decl))))
871 error ("%Jregister specified for '%D' isn't suitable for data type",
873 /* Now handle properly declared static register variables. */
878 if (DECL_INITIAL (decl) != 0 && TREE_STATIC (decl))
880 DECL_INITIAL (decl) = 0;
881 error ("global register variable has initial value");
883 if (TREE_THIS_VOLATILE (decl))
884 warning ("volatile register variables don't work as you might wish");
886 /* If the user specified one of the eliminables registers here,
887 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
888 confused with that register and be eliminated. This usage is
889 somewhat suspect... */
891 SET_DECL_RTL (decl, gen_rtx_raw_REG (DECL_MODE (decl), reg_number));
892 ORIGINAL_REGNO (DECL_RTL (decl)) = reg_number;
893 REG_USERVAR_P (DECL_RTL (decl)) = 1;
895 if (TREE_STATIC (decl))
897 /* Make this register global, so not usable for anything
899 #ifdef ASM_DECLARE_REGISTER_GLOBAL
900 ASM_DECLARE_REGISTER_GLOBAL (asm_out_file, decl, reg_number, name);
902 nregs = hard_regno_nregs[reg_number][DECL_MODE (decl)];
904 globalize_reg (reg_number + --nregs);
907 /* As a register variable, it has no section. */
912 /* Now handle ordinary static variables and functions (in memory).
913 Also handle vars declared register invalidly. */
915 if (name[0] == '*' && (reg_number >= 0 || reg_number == -3))
916 error ("%Jregister name given for non-register variable '%D'", decl, decl);
918 /* Specifying a section attribute on a variable forces it into a
919 non-.bss section, and thus it cannot be common. */
920 if (TREE_CODE (decl) == VAR_DECL
921 && DECL_SECTION_NAME (decl) != NULL_TREE
922 && DECL_INITIAL (decl) == NULL_TREE
923 && DECL_COMMON (decl))
924 DECL_COMMON (decl) = 0;
926 /* Variables can't be both common and weak. */
927 if (TREE_CODE (decl) == VAR_DECL && DECL_WEAK (decl))
928 DECL_COMMON (decl) = 0;
930 x = gen_rtx_SYMBOL_REF (Pmode, name);
931 SYMBOL_REF_WEAK (x) = DECL_WEAK (decl);
932 SYMBOL_REF_DECL (x) = decl;
934 x = gen_rtx_MEM (DECL_MODE (decl), x);
935 if (TREE_CODE (decl) != FUNCTION_DECL)
936 set_mem_attributes (x, decl, 1);
937 SET_DECL_RTL (decl, x);
939 /* Optionally set flags or add text to the name to record information
940 such as that it is a function name.
941 If the name is changed, the macro ASM_OUTPUT_LABELREF
942 will have to know how to strip this information. */
943 targetm.encode_section_info (decl, DECL_RTL (decl), true);
945 /* Make this function static known to the mudflap runtime. */
946 if (flag_mudflap && TREE_CODE (decl) == VAR_DECL)
947 mudflap_enqueue_decl (decl);
950 /* Make the rtl for variable VAR be volatile.
951 Use this only for static variables. */
954 make_var_volatile (tree var)
956 if (!MEM_P (DECL_RTL (var)))
959 MEM_VOLATILE_P (DECL_RTL (var)) = 1;
962 /* Output a string of literal assembler code
963 for an `asm' keyword used between functions. */
966 assemble_asm (tree string)
970 if (TREE_CODE (string) == ADDR_EXPR)
971 string = TREE_OPERAND (string, 0);
973 fprintf (asm_out_file, "\t%s\n", TREE_STRING_POINTER (string));
976 /* Record an element in the table of global destructors. SYMBOL is
977 a SYMBOL_REF of the function to be called; PRIORITY is a number
978 between 0 and MAX_INIT_PRIORITY. */
981 default_stabs_asm_out_destructor (rtx symbol, int priority ATTRIBUTE_UNUSED)
983 /* Tell GNU LD that this is part of the static destructor set.
984 This will work for any system that uses stabs, most usefully
986 fprintf (asm_out_file, "%s\"___DTOR_LIST__\",22,0,0,", ASM_STABS_OP);
987 assemble_name (asm_out_file, XSTR (symbol, 0));
988 fputc ('\n', asm_out_file);
992 default_named_section_asm_out_destructor (rtx symbol, int priority)
994 const char *section = ".dtors";
997 /* ??? This only works reliably with the GNU linker. */
998 if (priority != DEFAULT_INIT_PRIORITY)
1000 sprintf (buf, ".dtors.%.5u",
1001 /* Invert the numbering so the linker puts us in the proper
1002 order; constructors are run from right to left, and the
1003 linker sorts in increasing order. */
1004 MAX_INIT_PRIORITY - priority);
1008 named_section_flags (section, SECTION_WRITE);
1009 assemble_align (POINTER_SIZE);
1010 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1013 #ifdef DTORS_SECTION_ASM_OP
1015 dtors_section (void)
1017 if (in_section != in_dtors)
1019 in_section = in_dtors;
1020 fputs (DTORS_SECTION_ASM_OP, asm_out_file);
1021 fputc ('\n', asm_out_file);
1026 default_dtor_section_asm_out_destructor (rtx symbol,
1027 int priority ATTRIBUTE_UNUSED)
1030 assemble_align (POINTER_SIZE);
1031 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1035 /* Likewise for global constructors. */
1038 default_stabs_asm_out_constructor (rtx symbol, int priority ATTRIBUTE_UNUSED)
1040 /* Tell GNU LD that this is part of the static destructor set.
1041 This will work for any system that uses stabs, most usefully
1043 fprintf (asm_out_file, "%s\"___CTOR_LIST__\",22,0,0,", ASM_STABS_OP);
1044 assemble_name (asm_out_file, XSTR (symbol, 0));
1045 fputc ('\n', asm_out_file);
1049 default_named_section_asm_out_constructor (rtx symbol, int priority)
1051 const char *section = ".ctors";
1054 /* ??? This only works reliably with the GNU linker. */
1055 if (priority != DEFAULT_INIT_PRIORITY)
1057 sprintf (buf, ".ctors.%.5u",
1058 /* Invert the numbering so the linker puts us in the proper
1059 order; constructors are run from right to left, and the
1060 linker sorts in increasing order. */
1061 MAX_INIT_PRIORITY - priority);
1065 named_section_flags (section, SECTION_WRITE);
1066 assemble_align (POINTER_SIZE);
1067 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1070 #ifdef CTORS_SECTION_ASM_OP
1072 ctors_section (void)
1074 if (in_section != in_ctors)
1076 in_section = in_ctors;
1077 fputs (CTORS_SECTION_ASM_OP, asm_out_file);
1078 fputc ('\n', asm_out_file);
1083 default_ctor_section_asm_out_constructor (rtx symbol,
1084 int priority ATTRIBUTE_UNUSED)
1087 assemble_align (POINTER_SIZE);
1088 assemble_integer (symbol, POINTER_SIZE / BITS_PER_UNIT, POINTER_SIZE, 1);
1092 /* CONSTANT_POOL_BEFORE_FUNCTION may be defined as an expression with
1093 a nonzero value if the constant pool should be output before the
1094 start of the function, or a zero value if the pool should output
1095 after the end of the function. The default is to put it before the
1098 #ifndef CONSTANT_POOL_BEFORE_FUNCTION
1099 #define CONSTANT_POOL_BEFORE_FUNCTION 1
1102 /* DECL is an object (either VAR_DECL or FUNCTION_DECL) which is going
1103 to be output to assembler.
1104 Set first_global_object_name and weak_global_object_name as appropriate. */
1107 notice_global_symbol (tree decl)
1109 const char **type = &first_global_object_name;
1111 if (first_global_object_name
1112 || !TREE_PUBLIC (decl) || DECL_EXTERNAL (decl)
1113 || !DECL_NAME (decl)
1114 || (TREE_CODE (decl) != FUNCTION_DECL
1115 && (TREE_CODE (decl) != VAR_DECL
1116 || (DECL_COMMON (decl)
1117 && (DECL_INITIAL (decl) == 0
1118 || DECL_INITIAL (decl) == error_mark_node))))
1119 || !MEM_P (DECL_RTL (decl)))
1122 /* We win when global object is found, but it is useful to know about weak
1123 symbol as well so we can produce nicer unique names. */
1124 if (DECL_WEAK (decl) || DECL_ONE_ONLY (decl))
1125 type = &weak_global_object_name;
1131 rtx decl_rtl = DECL_RTL (decl);
1133 p = targetm.strip_name_encoding (XSTR (XEXP (decl_rtl, 0), 0));
1140 /* Output assembler code for the constant pool of a function and associated
1141 with defining the name of the function. DECL describes the function.
1142 NAME is the function's name. For the constant pool, we use the current
1143 constant pool data. */
1146 assemble_start_function (tree decl, const char *fnname)
1150 if (unlikely_text_section_name)
1151 free (unlikely_text_section_name);
1153 unlikely_section_label_printed = false;
1154 unlikely_text_section_name = NULL;
1156 if (unlikely_section_label)
1157 free (unlikely_section_label);
1158 unlikely_section_label = xmalloc ((strlen (fnname) + 18) * sizeof (char));
1159 sprintf (unlikely_section_label, "%s_unlikely_section", 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 /* Make sure the cold text (code) section is properly aligned. This
1169 is necessary here in the case where the function has both hot and
1170 cold sections, because we don't want to re-set the alignment when the
1171 section switch happens mid-function. We don't need to set the hot
1172 section alignment here, because code further down in this function
1173 sets the alignment for whichever section comes first, and if there
1174 is a hot section it is guaranteed to be first. */
1176 if (flag_reorder_blocks_and_partition)
1178 unlikely_text_section ();
1179 assemble_align (FUNCTION_BOUNDARY);
1182 resolve_unique_section (decl, 0, flag_function_sections);
1183 function_section (decl);
1185 /* Tell assembler to move to target machine's alignment for functions. */
1186 align = floor_log2 (FUNCTION_BOUNDARY / BITS_PER_UNIT);
1187 if (align < force_align_functions_log)
1188 align = force_align_functions_log;
1191 ASM_OUTPUT_ALIGN (asm_out_file, align);
1194 /* Handle a user-specified function alignment.
1195 Note that we still need to align to FUNCTION_BOUNDARY, as above,
1196 because ASM_OUTPUT_MAX_SKIP_ALIGN might not do any alignment at all. */
1197 if (align_functions_log > align
1198 && cfun->function_frequency != FUNCTION_FREQUENCY_UNLIKELY_EXECUTED)
1200 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
1201 ASM_OUTPUT_MAX_SKIP_ALIGN (asm_out_file,
1202 align_functions_log, align_functions - 1);
1204 ASM_OUTPUT_ALIGN (asm_out_file, align_functions_log);
1208 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
1209 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
1212 (*debug_hooks->begin_function) (decl);
1214 /* Make function name accessible from other files, if appropriate. */
1216 if (TREE_PUBLIC (decl))
1218 notice_global_symbol (decl);
1220 globalize_decl (decl);
1222 maybe_assemble_visibility (decl);
1225 if (DECL_PRESERVE_P (decl))
1226 targetm.asm_out.mark_decl_preserved (fnname);
1228 /* Do any machine/system dependent processing of the function name. */
1229 #ifdef ASM_DECLARE_FUNCTION_NAME
1230 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
1232 /* Standard thing is just output label for the function. */
1233 ASM_OUTPUT_LABEL (asm_out_file, fnname);
1234 #endif /* ASM_DECLARE_FUNCTION_NAME */
1236 if (in_unlikely_text_section ()
1237 && !unlikely_section_label_printed)
1239 ASM_OUTPUT_LABEL (asm_out_file, unlikely_section_label);
1240 unlikely_section_label_printed = true;
1244 /* Output assembler code associated with defining the size of the
1245 function. DECL describes the function. NAME is the function's name. */
1248 assemble_end_function (tree decl, const char *fnname)
1250 #ifdef ASM_DECLARE_FUNCTION_SIZE
1251 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
1253 if (! CONSTANT_POOL_BEFORE_FUNCTION)
1255 output_constant_pool (fnname, decl);
1256 function_section (decl); /* need to switch back */
1260 /* Assemble code to leave SIZE bytes of zeros. */
1263 assemble_zeros (unsigned HOST_WIDE_INT size)
1265 /* Do no output if -fsyntax-only. */
1266 if (flag_syntax_only)
1269 #ifdef ASM_NO_SKIP_IN_TEXT
1270 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
1271 so we must output 0s explicitly in the text section. */
1272 if ((ASM_NO_SKIP_IN_TEXT && in_text_section ())
1273 || (ASM_NO_SKIP_IN_TEXT && in_unlikely_text_section ()))
1275 unsigned HOST_WIDE_INT i;
1276 for (i = 0; i < size; i++)
1277 assemble_integer (const0_rtx, 1, BITS_PER_UNIT, 1);
1282 ASM_OUTPUT_SKIP (asm_out_file, size);
1285 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
1288 assemble_align (int align)
1290 if (align > BITS_PER_UNIT)
1292 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1296 /* Assemble a string constant with the specified C string as contents. */
1299 assemble_string (const char *p, int size)
1304 /* If the string is very long, split it up. */
1308 int thissize = size - pos;
1309 if (thissize > maximum)
1312 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
1320 #if defined ASM_OUTPUT_ALIGNED_DECL_LOCAL
1321 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1322 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1324 #if defined ASM_OUTPUT_ALIGNED_LOCAL
1325 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1326 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, DECL_ALIGN (decl))
1328 #define ASM_EMIT_LOCAL(decl, name, size, rounded) \
1329 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded)
1333 #if defined ASM_OUTPUT_ALIGNED_BSS
1334 #define ASM_EMIT_BSS(decl, name, size, rounded) \
1335 ASM_OUTPUT_ALIGNED_BSS (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1337 #if defined ASM_OUTPUT_BSS
1338 #define ASM_EMIT_BSS(decl, name, size, rounded) \
1339 ASM_OUTPUT_BSS (asm_out_file, decl, name, size, rounded)
1345 #if defined ASM_OUTPUT_ALIGNED_DECL_COMMON
1346 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1347 ASM_OUTPUT_ALIGNED_DECL_COMMON (asm_out_file, decl, name, size, DECL_ALIGN (decl))
1349 #if defined ASM_OUTPUT_ALIGNED_COMMON
1350 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1351 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size, DECL_ALIGN (decl))
1353 #define ASM_EMIT_COMMON(decl, name, size, rounded) \
1354 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded)
1359 asm_emit_uninitialised (tree decl, const char *name,
1360 unsigned HOST_WIDE_INT size ATTRIBUTE_UNUSED,
1361 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED)
1369 destination = asm_dest_local;
1371 /* ??? We should handle .bss via select_section mechanisms rather than
1372 via special target hooks. That would eliminate this special case. */
1373 if (TREE_PUBLIC (decl))
1375 if (!DECL_COMMON (decl))
1377 destination = asm_dest_bss;
1382 destination = asm_dest_common;
1385 if (destination == asm_dest_bss)
1386 globalize_decl (decl);
1387 resolve_unique_section (decl, 0, flag_data_sections);
1389 if (flag_shared_data)
1391 switch (destination)
1393 #ifdef ASM_OUTPUT_SHARED_BSS
1395 ASM_OUTPUT_SHARED_BSS (asm_out_file, decl, name, size, rounded);
1398 #ifdef ASM_OUTPUT_SHARED_COMMON
1399 case asm_dest_common:
1400 ASM_OUTPUT_SHARED_COMMON (asm_out_file, name, size, rounded);
1403 #ifdef ASM_OUTPUT_SHARED_LOCAL
1404 case asm_dest_local:
1405 ASM_OUTPUT_SHARED_LOCAL (asm_out_file, name, size, rounded);
1413 switch (destination)
1417 ASM_EMIT_BSS (decl, name, size, rounded);
1420 case asm_dest_common:
1421 ASM_EMIT_COMMON (decl, name, size, rounded);
1423 case asm_dest_local:
1424 ASM_EMIT_LOCAL (decl, name, size, rounded);
1433 /* Assemble everything that is needed for a variable or function declaration.
1434 Not used for automatic variables, and not used for function definitions.
1435 Should not be called for variables of incomplete structure type.
1437 TOP_LEVEL is nonzero if this variable has file scope.
1438 AT_END is nonzero if this is the special handling, at end of compilation,
1439 to define things that have had only tentative definitions.
1440 DONT_OUTPUT_DATA if nonzero means don't actually output the
1441 initial value (that will be done by the caller). */
1444 assemble_variable (tree decl, int top_level ATTRIBUTE_UNUSED,
1445 int at_end ATTRIBUTE_UNUSED, int dont_output_data)
1452 if (lang_hooks.decls.prepare_assemble_variable)
1453 lang_hooks.decls.prepare_assemble_variable (decl);
1455 last_assemble_variable_decl = 0;
1457 /* Normally no need to say anything here for external references,
1458 since assemble_external is called by the language-specific code
1459 when a declaration is first seen. */
1461 if (DECL_EXTERNAL (decl))
1464 /* Output no assembler code for a function declaration.
1465 Only definitions of functions output anything. */
1467 if (TREE_CODE (decl) == FUNCTION_DECL)
1470 /* Do nothing for global register variables. */
1471 if (DECL_RTL_SET_P (decl) && REG_P (DECL_RTL (decl)))
1473 TREE_ASM_WRITTEN (decl) = 1;
1477 /* If type was incomplete when the variable was declared,
1478 see if it is complete now. */
1480 if (DECL_SIZE (decl) == 0)
1481 layout_decl (decl, 0);
1483 /* Still incomplete => don't allocate it; treat the tentative defn
1484 (which is what it must have been) as an `extern' reference. */
1486 if (!dont_output_data && DECL_SIZE (decl) == 0)
1488 error ("%Jstorage size of `%D' isn't known", decl, decl);
1489 TREE_ASM_WRITTEN (decl) = 1;
1493 /* The first declaration of a variable that comes through this function
1494 decides whether it is global (in C, has external linkage)
1495 or local (in C, has internal linkage). So do nothing more
1496 if this function has already run. */
1498 if (TREE_ASM_WRITTEN (decl))
1501 /* Make sure targetm.encode_section_info is invoked before we set
1503 decl_rtl = DECL_RTL (decl);
1505 TREE_ASM_WRITTEN (decl) = 1;
1507 /* Do no output if -fsyntax-only. */
1508 if (flag_syntax_only)
1513 if (! dont_output_data
1514 && ! host_integerp (DECL_SIZE_UNIT (decl), 1))
1516 error ("%Jsize of variable '%D' is too large", decl, decl);
1520 name = XSTR (XEXP (decl_rtl, 0), 0);
1521 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
1522 notice_global_symbol (decl);
1524 /* Compute the alignment of this data. */
1526 align = DECL_ALIGN (decl);
1528 /* In the case for initialing an array whose length isn't specified,
1529 where we have not yet been able to do the layout,
1530 figure out the proper alignment now. */
1531 if (dont_output_data && DECL_SIZE (decl) == 0
1532 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
1533 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
1535 /* Some object file formats have a maximum alignment which they support.
1536 In particular, a.out format supports a maximum alignment of 4. */
1537 #ifndef MAX_OFILE_ALIGNMENT
1538 #define MAX_OFILE_ALIGNMENT BIGGEST_ALIGNMENT
1540 if (align > MAX_OFILE_ALIGNMENT)
1542 warning ("%Jalignment of '%D' is greater than maximum object "
1543 "file alignment. Using %d", decl, decl,
1544 MAX_OFILE_ALIGNMENT/BITS_PER_UNIT);
1545 align = MAX_OFILE_ALIGNMENT;
1548 /* On some machines, it is good to increase alignment sometimes. */
1549 if (! DECL_USER_ALIGN (decl))
1551 #ifdef DATA_ALIGNMENT
1552 align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1554 #ifdef CONSTANT_ALIGNMENT
1555 if (DECL_INITIAL (decl) != 0 && DECL_INITIAL (decl) != error_mark_node)
1556 align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
1560 /* Reset the alignment in case we have made it tighter, so we can benefit
1561 from it in get_pointer_alignment. */
1562 DECL_ALIGN (decl) = align;
1563 set_mem_align (decl_rtl, align);
1565 if (TREE_PUBLIC (decl))
1566 maybe_assemble_visibility (decl);
1568 if (DECL_PRESERVE_P (decl))
1569 targetm.asm_out.mark_decl_preserved (name);
1571 /* Output any data that we will need to use the address of. */
1572 if (DECL_INITIAL (decl) == error_mark_node)
1573 reloc = contains_pointers_p (TREE_TYPE (decl)) ? 3 : 0;
1574 else if (DECL_INITIAL (decl))
1576 reloc = compute_reloc_for_constant (DECL_INITIAL (decl));
1577 output_addressed_constants (DECL_INITIAL (decl));
1579 resolve_unique_section (decl, reloc, flag_data_sections);
1581 /* Handle uninitialized definitions. */
1583 /* If the decl has been given an explicit section name, then it
1584 isn't common, and shouldn't be handled as such. */
1585 if (DECL_SECTION_NAME (decl) || dont_output_data)
1587 /* We don't implement common thread-local data at present. */
1588 else if (DECL_THREAD_LOCAL (decl))
1590 if (DECL_COMMON (decl))
1591 sorry ("thread-local COMMON data not implemented");
1593 else if (DECL_INITIAL (decl) == 0
1594 || DECL_INITIAL (decl) == error_mark_node
1595 || (flag_zero_initialized_in_bss
1596 /* Leave constant zeroes in .rodata so they can be shared. */
1597 && !TREE_READONLY (decl)
1598 && initializer_zerop (DECL_INITIAL (decl))))
1600 unsigned HOST_WIDE_INT size = tree_low_cst (DECL_SIZE_UNIT (decl), 1);
1601 unsigned HOST_WIDE_INT rounded = size;
1603 /* Don't allocate zero bytes of common,
1604 since that means "undefined external" in the linker. */
1608 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1609 so that each uninitialized object starts on such a boundary. */
1610 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
1611 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1612 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1614 #if !defined(ASM_OUTPUT_ALIGNED_COMMON) && !defined(ASM_OUTPUT_ALIGNED_DECL_COMMON) && !defined(ASM_OUTPUT_ALIGNED_BSS)
1615 if ((unsigned HOST_WIDE_INT) DECL_ALIGN (decl) / BITS_PER_UNIT > rounded)
1616 warning ("%Jrequested alignment for '%D' is greater than "
1617 "implemented alignment of %d", decl, decl, rounded);
1620 /* If the target cannot output uninitialized but not common global data
1621 in .bss, then we have to use .data, so fall through. */
1622 if (asm_emit_uninitialised (decl, name, size, rounded))
1626 /* Handle initialized definitions.
1627 Also handle uninitialized global definitions if -fno-common and the
1628 target doesn't support ASM_OUTPUT_BSS. */
1630 /* First make the assembler name(s) global if appropriate. */
1631 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
1632 globalize_decl (decl);
1634 /* Switch to the appropriate section. */
1635 variable_section (decl, reloc);
1637 /* dbxout.c needs to know this. */
1638 if (in_text_section () || in_unlikely_text_section ())
1639 DECL_IN_TEXT_SECTION (decl) = 1;
1641 /* Output the alignment of this data. */
1642 if (align > BITS_PER_UNIT)
1644 ASM_OUTPUT_ALIGN (asm_out_file,
1645 floor_log2 (DECL_ALIGN (decl) / BITS_PER_UNIT));
1648 /* Do any machine/system dependent processing of the object. */
1649 #ifdef ASM_DECLARE_OBJECT_NAME
1650 last_assemble_variable_decl = decl;
1651 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
1653 /* Standard thing is just output label for the object. */
1654 ASM_OUTPUT_LABEL (asm_out_file, name);
1655 #endif /* ASM_DECLARE_OBJECT_NAME */
1657 if (!dont_output_data)
1659 if (DECL_INITIAL (decl)
1660 && DECL_INITIAL (decl) != error_mark_node
1661 && !initializer_zerop (DECL_INITIAL (decl)))
1662 /* Output the actual data. */
1663 output_constant (DECL_INITIAL (decl),
1664 tree_low_cst (DECL_SIZE_UNIT (decl), 1),
1667 /* Leave space for it. */
1668 assemble_zeros (tree_low_cst (DECL_SIZE_UNIT (decl), 1));
1672 /* Return 1 if type TYPE contains any pointers. */
1675 contains_pointers_p (tree type)
1677 switch (TREE_CODE (type))
1680 case REFERENCE_TYPE:
1681 /* I'm not sure whether OFFSET_TYPE needs this treatment,
1682 so I'll play safe and return 1. */
1688 case QUAL_UNION_TYPE:
1691 /* For a type that has fields, see if the fields have pointers. */
1692 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
1693 if (TREE_CODE (fields) == FIELD_DECL
1694 && contains_pointers_p (TREE_TYPE (fields)))
1700 /* An array type contains pointers if its element type does. */
1701 return contains_pointers_p (TREE_TYPE (type));
1708 #ifdef ASM_OUTPUT_EXTERNAL
1709 /* True if DECL is a function decl for which no out-of-line copy exists.
1710 It is assumed that DECL's assembler name has been set. */
1713 incorporeal_function_p (tree decl)
1715 if (TREE_CODE (decl) == FUNCTION_DECL && DECL_BUILT_IN (decl))
1719 if (DECL_BUILT_IN_CLASS (decl) == BUILT_IN_NORMAL
1720 && DECL_FUNCTION_CODE (decl) == BUILT_IN_ALLOCA)
1723 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
1724 if (strncmp (name, "__builtin_", strlen ("__builtin_")) == 0)
1731 /* Output something to declare an external symbol to the assembler.
1732 (Most assemblers don't need this, so we normally output nothing.)
1733 Do nothing if DECL is not external. */
1736 assemble_external (tree decl ATTRIBUTE_UNUSED)
1738 /* Because most platforms do not define ASM_OUTPUT_EXTERNAL, the
1739 main body of this code is only rarely exercised. To provide some
1740 testing, on all platforms, we make sure that the ASM_OUT_FILE is
1741 open. If it's not, we should not be calling this function. */
1745 #ifdef ASM_OUTPUT_EXTERNAL
1746 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
1748 rtx rtl = DECL_RTL (decl);
1750 if (MEM_P (rtl) && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
1751 && !SYMBOL_REF_USED (XEXP (rtl, 0))
1752 && !incorporeal_function_p (decl))
1754 /* Some systems do require some output. */
1755 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
1756 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
1762 /* Similar, for calling a library function FUN. */
1765 assemble_external_libcall (rtx fun)
1767 /* Declare library function name external when first used, if nec. */
1768 if (! SYMBOL_REF_USED (fun))
1770 SYMBOL_REF_USED (fun) = 1;
1771 targetm.asm_out.external_libcall (fun);
1775 /* Assemble a label named NAME. */
1778 assemble_label (const char *name)
1780 ASM_OUTPUT_LABEL (asm_out_file, name);
1783 /* Set the symbol_referenced flag for ID. */
1785 mark_referenced (tree id)
1787 TREE_SYMBOL_REFERENCED (id) = 1;
1790 /* Set the symbol_referenced flag for DECL and notify callgraph. */
1792 mark_decl_referenced (tree decl)
1794 if (TREE_CODE (decl) == FUNCTION_DECL)
1795 cgraph_mark_needed_node (cgraph_node (decl));
1796 else if (TREE_CODE (decl) == VAR_DECL)
1797 cgraph_varpool_mark_needed_node (cgraph_varpool_node (decl));
1798 /* else do nothing - we can get various sorts of CST nodes here,
1799 which do not need to be marked. */
1802 /* Output to FILE a reference to the assembler name of a C-level name NAME.
1803 If NAME starts with a *, the rest of NAME is output verbatim.
1804 Otherwise NAME is transformed in an implementation-defined way
1805 (usually by the addition of an underscore).
1806 Many macros in the tm file are defined to call this function. */
1809 assemble_name (FILE *file, const char *name)
1811 const char *real_name;
1814 real_name = targetm.strip_name_encoding (name);
1816 id = maybe_get_identifier (real_name);
1818 mark_referenced (id);
1821 fputs (&name[1], file);
1823 ASM_OUTPUT_LABELREF (file, name);
1826 /* Allocate SIZE bytes writable static space with a gensym name
1827 and return an RTX to refer to its address. */
1830 assemble_static_space (unsigned HOST_WIDE_INT size)
1833 const char *namestring;
1837 if (flag_shared_data)
1841 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
1843 namestring = ggc_strdup (name);
1845 x = gen_rtx_SYMBOL_REF (Pmode, namestring);
1846 SYMBOL_REF_FLAGS (x) = SYMBOL_FLAG_LOCAL;
1848 #ifdef ASM_OUTPUT_ALIGNED_DECL_LOCAL
1849 ASM_OUTPUT_ALIGNED_DECL_LOCAL (asm_out_file, NULL_TREE, name, size,
1852 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
1853 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
1856 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1857 so that each uninitialized object starts on such a boundary. */
1858 /* Variable `rounded' might or might not be used in ASM_OUTPUT_LOCAL. */
1859 unsigned HOST_WIDE_INT rounded ATTRIBUTE_UNUSED
1860 = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
1861 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1862 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1863 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1870 /* Assemble the static constant template for function entry trampolines.
1871 This is done at most once per compilation.
1872 Returns an RTX for the address of the template. */
1874 static GTY(()) rtx initial_trampoline;
1876 #ifdef TRAMPOLINE_TEMPLATE
1878 assemble_trampoline_template (void)
1885 if (initial_trampoline)
1886 return initial_trampoline;
1888 /* By default, put trampoline templates in read-only data section. */
1890 #ifdef TRAMPOLINE_SECTION
1891 TRAMPOLINE_SECTION ();
1893 readonly_data_section ();
1896 /* Write the assembler code to define one. */
1897 align = floor_log2 (TRAMPOLINE_ALIGNMENT / BITS_PER_UNIT);
1900 ASM_OUTPUT_ALIGN (asm_out_file, align);
1903 targetm.asm_out.internal_label (asm_out_file, "LTRAMP", 0);
1904 TRAMPOLINE_TEMPLATE (asm_out_file);
1906 /* Record the rtl to refer to it. */
1907 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
1908 name = ggc_strdup (label);
1909 symbol = gen_rtx_SYMBOL_REF (Pmode, name);
1910 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
1912 initial_trampoline = gen_rtx_MEM (BLKmode, symbol);
1913 set_mem_align (initial_trampoline, TRAMPOLINE_ALIGNMENT);
1915 return initial_trampoline;
1919 /* A and B are either alignments or offsets. Return the minimum alignment
1920 that may be assumed after adding the two together. */
1922 static inline unsigned
1923 min_align (unsigned int a, unsigned int b)
1925 return (a | b) & -(a | b);
1928 /* Return the assembler directive for creating a given kind of integer
1929 object. SIZE is the number of bytes in the object and ALIGNED_P
1930 indicates whether it is known to be aligned. Return NULL if the
1931 assembly dialect has no such directive.
1933 The returned string should be printed at the start of a new line and
1934 be followed immediately by the object's initial value. */
1937 integer_asm_op (int size, int aligned_p)
1939 struct asm_int_op *ops;
1942 ops = &targetm.asm_out.aligned_op;
1944 ops = &targetm.asm_out.unaligned_op;
1949 return targetm.asm_out.byte_op;
1963 /* Use directive OP to assemble an integer object X. Print OP at the
1964 start of the line, followed immediately by the value of X. */
1967 assemble_integer_with_op (const char *op, rtx x)
1969 fputs (op, asm_out_file);
1970 output_addr_const (asm_out_file, x);
1971 fputc ('\n', asm_out_file);
1974 /* The default implementation of the asm_out.integer target hook. */
1977 default_assemble_integer (rtx x ATTRIBUTE_UNUSED,
1978 unsigned int size ATTRIBUTE_UNUSED,
1979 int aligned_p ATTRIBUTE_UNUSED)
1981 const char *op = integer_asm_op (size, aligned_p);
1982 return op && (assemble_integer_with_op (op, x), true);
1985 /* Assemble the integer constant X into an object of SIZE bytes. ALIGN is
1986 the alignment of the integer in bits. Return 1 if we were able to output
1987 the constant, otherwise 0. If FORCE is nonzero, abort if we can't output
1991 assemble_integer (rtx x, unsigned int size, unsigned int align, int force)
1995 aligned_p = (align >= MIN (size * BITS_PER_UNIT, BIGGEST_ALIGNMENT));
1997 /* See if the target hook can handle this kind of object. */
1998 if (targetm.asm_out.integer (x, size, aligned_p))
2001 /* If the object is a multi-byte one, try splitting it up. Split
2002 it into words it if is multi-word, otherwise split it into bytes. */
2005 enum machine_mode omode, imode;
2006 unsigned int subalign;
2007 unsigned int subsize, i;
2009 subsize = size > UNITS_PER_WORD? UNITS_PER_WORD : 1;
2010 subalign = MIN (align, subsize * BITS_PER_UNIT);
2011 omode = mode_for_size (subsize * BITS_PER_UNIT, MODE_INT, 0);
2012 imode = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
2014 for (i = 0; i < size; i += subsize)
2016 rtx partial = simplify_subreg (omode, x, imode, i);
2017 if (!partial || !assemble_integer (partial, subsize, subalign, 0))
2023 /* If we've printed some of it, but not all of it, there's no going
2036 assemble_real (REAL_VALUE_TYPE d, enum machine_mode mode, unsigned int align)
2040 int bitsize, nelts, nunits, units_per;
2042 /* This is hairy. We have a quantity of known size. real_to_target
2043 will put it into an array of *host* longs, 32 bits per element
2044 (even if long is more than 32 bits). We need to determine the
2045 number of array elements that are occupied (nelts) and the number
2046 of *target* min-addressable units that will be occupied in the
2047 object file (nunits). We cannot assume that 32 divides the
2048 mode's bitsize (size * BITS_PER_UNIT) evenly.
2050 size * BITS_PER_UNIT is used here to make sure that padding bits
2051 (which might appear at either end of the value; real_to_target
2052 will include the padding bits in its output array) are included. */
2054 nunits = GET_MODE_SIZE (mode);
2055 bitsize = nunits * BITS_PER_UNIT;
2056 nelts = CEIL (bitsize, 32);
2057 units_per = 32 / BITS_PER_UNIT;
2059 real_to_target (data, &d, mode);
2061 /* Put out the first word with the specified alignment. */
2062 assemble_integer (GEN_INT (data[0]), MIN (nunits, units_per), align, 1);
2063 nunits -= units_per;
2065 /* Subsequent words need only 32-bit alignment. */
2066 align = min_align (align, 32);
2068 for (i = 1; i < nelts; i++)
2070 assemble_integer (GEN_INT (data[i]), MIN (nunits, units_per), align, 1);
2071 nunits -= units_per;
2075 /* Given an expression EXP with a constant value,
2076 reduce it to the sum of an assembler symbol and an integer.
2077 Store them both in the structure *VALUE.
2078 Abort if EXP does not reduce. */
2080 struct addr_const GTY(())
2083 HOST_WIDE_INT offset;
2087 decode_addr_const (tree exp, struct addr_const *value)
2089 tree target = TREE_OPERAND (exp, 0);
2095 if (TREE_CODE (target) == COMPONENT_REF
2096 && host_integerp (byte_position (TREE_OPERAND (target, 1)), 0))
2099 offset += int_byte_position (TREE_OPERAND (target, 1));
2100 target = TREE_OPERAND (target, 0);
2102 else if (TREE_CODE (target) == ARRAY_REF
2103 || TREE_CODE (target) == ARRAY_RANGE_REF)
2105 offset += (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (target)), 1)
2106 * tree_low_cst (TREE_OPERAND (target, 1), 0));
2107 target = TREE_OPERAND (target, 0);
2113 switch (TREE_CODE (target))
2117 x = DECL_RTL (target);
2121 x = gen_rtx_MEM (FUNCTION_MODE,
2122 gen_rtx_LABEL_REF (VOIDmode, force_label_rtx (target)));
2130 x = output_constant_def (target, 1);
2142 value->offset = offset;
2145 /* Uniquize all constants that appear in memory.
2146 Each constant in memory thus far output is recorded
2147 in `const_desc_table'. */
2149 struct constant_descriptor_tree GTY(())
2151 /* A MEM for the constant. */
2154 /* The value of the constant. */
2158 static GTY((param_is (struct constant_descriptor_tree)))
2159 htab_t const_desc_htab;
2161 static struct constant_descriptor_tree * build_constant_desc (tree);
2162 static void maybe_output_constant_def_contents (struct constant_descriptor_tree *, int);
2164 /* Compute a hash code for a constant expression. */
2167 const_desc_hash (const void *ptr)
2169 return const_hash_1 (((struct constant_descriptor_tree *)ptr)->value);
2173 const_hash_1 (const tree exp)
2178 enum tree_code code = TREE_CODE (exp);
2180 /* Either set P and LEN to the address and len of something to hash and
2181 exit the switch or return a value. */
2186 p = (char *) &TREE_INT_CST (exp);
2187 len = sizeof TREE_INT_CST (exp);
2191 return real_hash (TREE_REAL_CST_PTR (exp));
2194 p = TREE_STRING_POINTER (exp);
2195 len = TREE_STRING_LENGTH (exp);
2199 return (const_hash_1 (TREE_REALPART (exp)) * 5
2200 + const_hash_1 (TREE_IMAGPART (exp)));
2203 if (TREE_CODE (TREE_TYPE (exp)) == SET_TYPE)
2207 len = int_size_in_bytes (TREE_TYPE (exp));
2209 get_set_constructor_bytes (exp, (unsigned char *) tmp, len);
2217 hi = 5 + int_size_in_bytes (TREE_TYPE (exp));
2219 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link))
2220 if (TREE_VALUE (link))
2221 hi = hi * 603 + const_hash_1 (TREE_VALUE (link));
2229 struct addr_const value;
2231 decode_addr_const (exp, &value);
2232 if (GET_CODE (value.base) == SYMBOL_REF)
2234 /* Don't hash the address of the SYMBOL_REF;
2235 only use the offset and the symbol name. */
2237 p = XSTR (value.base, 0);
2238 for (i = 0; p[i] != 0; i++)
2239 hi = ((hi * 613) + (unsigned) (p[i]));
2241 else if (GET_CODE (value.base) == LABEL_REF)
2242 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13;
2250 return (const_hash_1 (TREE_OPERAND (exp, 0)) * 9
2251 + const_hash_1 (TREE_OPERAND (exp, 1)));
2255 case NON_LVALUE_EXPR:
2256 return const_hash_1 (TREE_OPERAND (exp, 0)) * 7 + 2;
2259 /* A language specific constant. Just hash the code. */
2263 /* Compute hashing function. */
2265 for (i = 0; i < len; i++)
2266 hi = ((hi * 613) + (unsigned) (p[i]));
2271 /* Wrapper of compare_constant, for the htab interface. */
2273 const_desc_eq (const void *p1, const void *p2)
2275 return compare_constant (((struct constant_descriptor_tree *)p1)->value,
2276 ((struct constant_descriptor_tree *)p2)->value);
2279 /* Compare t1 and t2, and return 1 only if they are known to result in
2280 the same bit pattern on output. */
2283 compare_constant (const tree t1, const tree t2)
2285 enum tree_code typecode;
2287 if (t1 == NULL_TREE)
2288 return t2 == NULL_TREE;
2289 if (t2 == NULL_TREE)
2292 if (TREE_CODE (t1) != TREE_CODE (t2))
2295 switch (TREE_CODE (t1))
2298 /* Integer constants are the same only if the same width of type. */
2299 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2301 return tree_int_cst_equal (t1, t2);
2304 /* Real constants are the same only if the same width of type. */
2305 if (TYPE_PRECISION (TREE_TYPE (t1)) != TYPE_PRECISION (TREE_TYPE (t2)))
2308 return REAL_VALUES_IDENTICAL (TREE_REAL_CST (t1), TREE_REAL_CST (t2));
2311 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2)))
2314 return (TREE_STRING_LENGTH (t1) == TREE_STRING_LENGTH (t2)
2315 && ! memcmp (TREE_STRING_POINTER (t1), TREE_STRING_POINTER (t2),
2316 TREE_STRING_LENGTH (t1)));
2319 return (compare_constant (TREE_REALPART (t1), TREE_REALPART (t2))
2320 && compare_constant (TREE_IMAGPART (t1), TREE_IMAGPART (t2)));
2323 typecode = TREE_CODE (TREE_TYPE (t1));
2324 if (typecode != TREE_CODE (TREE_TYPE (t2)))
2327 if (typecode == SET_TYPE)
2329 int len = int_size_in_bytes (TREE_TYPE (t2));
2330 unsigned char *tmp1, *tmp2;
2332 if (int_size_in_bytes (TREE_TYPE (t1)) != len)
2335 tmp1 = alloca (len);
2336 tmp2 = alloca (len);
2338 if (get_set_constructor_bytes (t1, tmp1, len) != NULL_TREE)
2340 if (get_set_constructor_bytes (t2, tmp2, len) != NULL_TREE)
2343 return memcmp (tmp1, tmp2, len) == 0;
2349 if (typecode == ARRAY_TYPE)
2351 HOST_WIDE_INT size_1 = int_size_in_bytes (TREE_TYPE (t1));
2352 /* For arrays, check that the sizes all match. */
2353 if (TYPE_MODE (TREE_TYPE (t1)) != TYPE_MODE (TREE_TYPE (t2))
2355 || size_1 != int_size_in_bytes (TREE_TYPE (t2)))
2360 /* For record and union constructors, require exact type
2362 if (TREE_TYPE (t1) != TREE_TYPE (t2))
2366 for (l1 = CONSTRUCTOR_ELTS (t1), l2 = CONSTRUCTOR_ELTS (t2);
2368 l1 = TREE_CHAIN (l1), l2 = TREE_CHAIN (l2))
2370 /* Check that each value is the same... */
2371 if (! compare_constant (TREE_VALUE (l1), TREE_VALUE (l2)))
2373 /* ... and that they apply to the same fields! */
2374 if (typecode == ARRAY_TYPE)
2376 if (! compare_constant (TREE_PURPOSE (l1),
2382 if (TREE_PURPOSE (l1) != TREE_PURPOSE (l2))
2387 return l1 == NULL_TREE && l2 == NULL_TREE;
2393 struct addr_const value1, value2;
2395 decode_addr_const (t1, &value1);
2396 decode_addr_const (t2, &value2);
2397 return (value1.offset == value2.offset
2398 && strcmp (XSTR (value1.base, 0), XSTR (value2.base, 0)) == 0);
2404 return (compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0))
2405 && compare_constant(TREE_OPERAND (t1, 1), TREE_OPERAND (t2, 1)));
2409 case NON_LVALUE_EXPR:
2410 case VIEW_CONVERT_EXPR:
2411 return compare_constant (TREE_OPERAND (t1, 0), TREE_OPERAND (t2, 0));
2416 nt1 = lang_hooks.expand_constant (t1);
2417 nt2 = lang_hooks.expand_constant (t2);
2418 if (nt1 != t1 || nt2 != t2)
2419 return compare_constant (nt1, nt2);
2425 /* Should not get here. */
2429 /* Make a copy of the whole tree structure for a constant. This
2430 handles the same types of nodes that compare_constant handles. */
2433 copy_constant (tree exp)
2435 switch (TREE_CODE (exp))
2438 /* For ADDR_EXPR, we do not want to copy the decl whose address
2439 is requested. We do want to copy constants though. */
2440 if (TREE_CODE_CLASS (TREE_CODE (TREE_OPERAND (exp, 0))) == 'c')
2441 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
2442 copy_constant (TREE_OPERAND (exp, 0)));
2444 return copy_node (exp);
2449 return copy_node (exp);
2452 return build_complex (TREE_TYPE (exp),
2453 copy_constant (TREE_REALPART (exp)),
2454 copy_constant (TREE_IMAGPART (exp)));
2458 return build2 (TREE_CODE (exp), TREE_TYPE (exp),
2459 copy_constant (TREE_OPERAND (exp, 0)),
2460 copy_constant (TREE_OPERAND (exp, 1)));
2464 case NON_LVALUE_EXPR:
2465 case VIEW_CONVERT_EXPR:
2466 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
2467 copy_constant (TREE_OPERAND (exp, 0)));
2471 tree copy = copy_node (exp);
2472 tree list = copy_list (CONSTRUCTOR_ELTS (exp));
2475 CONSTRUCTOR_ELTS (copy) = list;
2476 for (tail = list; tail; tail = TREE_CHAIN (tail))
2477 TREE_VALUE (tail) = copy_constant (TREE_VALUE (tail));
2478 if (TREE_CODE (TREE_TYPE (exp)) == SET_TYPE)
2479 for (tail = list; tail; tail = TREE_CHAIN (tail))
2480 TREE_PURPOSE (tail) = copy_constant (TREE_PURPOSE (tail));
2488 t = lang_hooks.expand_constant (exp);
2490 return copy_constant (t);
2497 /* Subroutine of output_constant_def:
2498 No constant equal to EXP is known to have been output.
2499 Make a constant descriptor to enter EXP in the hash table.
2500 Assign the label number and construct RTL to refer to the
2501 constant's location in memory.
2502 Caller is responsible for updating the hash table. */
2504 static struct constant_descriptor_tree *
2505 build_constant_desc (tree exp)
2511 struct constant_descriptor_tree *desc;
2513 desc = ggc_alloc (sizeof (*desc));
2514 desc->value = copy_constant (exp);
2516 /* Propagate marked-ness to copied constant. */
2517 if (flag_mudflap && mf_marked_p (exp))
2518 mf_mark (desc->value);
2520 /* Create a string containing the label name, in LABEL. */
2521 labelno = const_labelno++;
2522 ASM_GENERATE_INTERNAL_LABEL (label, "LC", labelno);
2524 /* We have a symbol name; construct the SYMBOL_REF and the MEM. */
2525 symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
2526 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2527 SYMBOL_REF_DECL (symbol) = desc->value;
2528 TREE_CONSTANT_POOL_ADDRESS_P (symbol) = 1;
2530 rtl = gen_rtx_MEM (TYPE_MODE (TREE_TYPE (exp)), symbol);
2531 set_mem_attributes (rtl, exp, 1);
2532 set_mem_alias_set (rtl, 0);
2533 set_mem_alias_set (rtl, const_alias_set);
2535 /* Set flags or add text to the name to record information, such as
2536 that it is a local symbol. If the name is changed, the macro
2537 ASM_OUTPUT_LABELREF will have to know how to strip this
2538 information. This call might invalidate our local variable
2539 SYMBOL; we can't use it afterward. */
2541 targetm.encode_section_info (exp, rtl, true);
2548 /* Return an rtx representing a reference to constant data in memory
2549 for the constant expression EXP.
2551 If assembler code for such a constant has already been output,
2552 return an rtx to refer to it.
2553 Otherwise, output such a constant in memory
2554 and generate an rtx for it.
2556 If DEFER is nonzero, this constant can be deferred and output only
2557 if referenced in the function after all optimizations.
2559 `const_desc_table' records which constants already have label strings. */
2562 output_constant_def (tree exp, int defer)
2564 struct constant_descriptor_tree *desc;
2565 struct constant_descriptor_tree key;
2568 /* Look up EXP in the table of constant descriptors. If we didn't find
2569 it, create a new one. */
2571 loc = htab_find_slot (const_desc_htab, &key, INSERT);
2576 desc = build_constant_desc (exp);
2580 maybe_output_constant_def_contents (desc, defer);
2584 /* Subroutine of output_constant_def: Decide whether or not we need to
2585 output the constant DESC now, and if so, do it. */
2587 maybe_output_constant_def_contents (struct constant_descriptor_tree *desc,
2590 rtx symbol = XEXP (desc->rtl, 0);
2591 tree exp = desc->value;
2593 if (flag_syntax_only)
2596 if (TREE_ASM_WRITTEN (exp))
2597 /* Already output; don't do it again. */
2600 /* We can always defer constants as long as the context allows
2604 /* Increment n_deferred_constants if it exists. It needs to be at
2605 least as large as the number of constants actually referred to
2606 by the function. If it's too small we'll stop looking too early
2607 and fail to emit constants; if it's too large we'll only look
2608 through the entire function when we could have stopped earlier. */
2610 n_deferred_constants++;
2614 output_constant_def_contents (symbol);
2617 /* We must output the constant data referred to by SYMBOL; do so. */
2620 output_constant_def_contents (rtx symbol)
2622 tree exp = SYMBOL_REF_DECL (symbol);
2623 const char *label = XSTR (symbol, 0);
2626 /* Make sure any other constants whose addresses appear in EXP
2627 are assigned label numbers. */
2628 int reloc = compute_reloc_for_constant (exp);
2630 /* Align the location counter as required by EXP's data type. */
2631 int align = TYPE_ALIGN (TREE_TYPE (exp));
2632 #ifdef CONSTANT_ALIGNMENT
2633 align = CONSTANT_ALIGNMENT (exp, align);
2636 output_addressed_constants (exp);
2638 /* We are no longer deferring this constant. */
2639 TREE_ASM_WRITTEN (exp) = 1;
2641 if (IN_NAMED_SECTION (exp))
2642 named_section (exp, NULL, reloc);
2644 targetm.asm_out.select_section (exp, reloc, align);
2646 if (align > BITS_PER_UNIT)
2648 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2651 size = int_size_in_bytes (TREE_TYPE (exp));
2652 if (TREE_CODE (exp) == STRING_CST)
2653 size = MAX (TREE_STRING_LENGTH (exp), size);
2655 /* Do any machine/system dependent processing of the constant. */
2656 #ifdef ASM_DECLARE_CONSTANT_NAME
2657 ASM_DECLARE_CONSTANT_NAME (asm_out_file, label, exp, size);
2659 /* Standard thing is just output label for the constant. */
2660 ASM_OUTPUT_LABEL (asm_out_file, label);
2661 #endif /* ASM_DECLARE_CONSTANT_NAME */
2663 /* Output the value of EXP. */
2664 output_constant (exp, size, align);
2666 mudflap_enqueue_constant (exp);
2669 /* Look up EXP in the table of constant descriptors. Return the rtl
2670 if it has been emitted, else null. */
2673 lookup_constant_def (tree exp)
2675 struct constant_descriptor_tree *desc;
2676 struct constant_descriptor_tree key;
2679 desc = htab_find (const_desc_htab, &key);
2681 return (desc ? desc->rtl : NULL_RTX);
2684 /* Used in the hash tables to avoid outputting the same constant
2685 twice. Unlike 'struct constant_descriptor_tree', RTX constants
2686 are output once per function, not once per file. */
2687 /* ??? Only a few targets need per-function constant pools. Most
2688 can use one per-file pool. Should add a targetm bit to tell the
2691 struct rtx_constant_pool GTY(())
2693 /* Pointers to first and last constant in pool, as ordered by offset. */
2694 struct constant_descriptor_rtx *first;
2695 struct constant_descriptor_rtx *last;
2697 /* Hash facility for making memory-constants from constant rtl-expressions.
2698 It is used on RISC machines where immediate integer arguments and
2699 constant addresses are restricted so that such constants must be stored
2701 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_htab;
2702 htab_t GTY((param_is (struct constant_descriptor_rtx))) const_rtx_sym_htab;
2704 /* Current offset in constant pool (does not include any
2705 machine-specific header). */
2706 HOST_WIDE_INT offset;
2709 struct constant_descriptor_rtx GTY((chain_next ("%h.next")))
2711 struct constant_descriptor_rtx *next;
2715 HOST_WIDE_INT offset;
2717 enum machine_mode mode;
2723 /* Hash and compare functions for const_rtx_htab. */
2726 const_desc_rtx_hash (const void *ptr)
2728 const struct constant_descriptor_rtx *desc = ptr;
2733 const_desc_rtx_eq (const void *a, const void *b)
2735 const struct constant_descriptor_rtx *x = a;
2736 const struct constant_descriptor_rtx *y = b;
2738 if (x->mode != y->mode)
2740 return rtx_equal_p (x->constant, y->constant);
2743 /* Hash and compare functions for const_rtx_sym_htab. */
2746 const_desc_rtx_sym_hash (const void *ptr)
2748 const struct constant_descriptor_rtx *desc = ptr;
2749 return htab_hash_string (XSTR (desc->sym, 0));
2753 const_desc_rtx_sym_eq (const void *a, const void *b)
2755 const struct constant_descriptor_rtx *x = a;
2756 const struct constant_descriptor_rtx *y = b;
2757 return XSTR (x->sym, 0) == XSTR (y->sym, 0);
2760 /* This is the worker function for const_rtx_hash, called via for_each_rtx. */
2763 const_rtx_hash_1 (rtx *xp, void *data)
2765 unsigned HOST_WIDE_INT hwi;
2766 enum machine_mode mode;
2772 code = GET_CODE (x);
2773 mode = GET_MODE (x);
2774 h = (hashval_t) code * 1048573 + mode;
2782 const int shift = sizeof (hashval_t) * CHAR_BIT;
2783 const int n = sizeof (HOST_WIDE_INT) / sizeof (hashval_t);
2786 h ^= (hashval_t) hwi;
2787 for (i = 1; i < n; ++i)
2790 h ^= (hashval_t) hwi;
2796 if (mode == VOIDmode)
2798 hwi = CONST_DOUBLE_LOW (x) ^ CONST_DOUBLE_HIGH (x);
2802 h ^= real_hash (CONST_DOUBLE_REAL_VALUE (x));
2806 h ^= htab_hash_string (XSTR (x, 0));
2810 h = h * 251 + CODE_LABEL_NUMBER (XEXP (x, 0));
2814 case UNSPEC_VOLATILE:
2815 h = h * 251 + XINT (x, 1);
2823 *hp = *hp * 509 + h;
2827 /* Compute a hash value for X, which should be a constant. */
2830 const_rtx_hash (rtx x)
2833 for_each_rtx (&x, const_rtx_hash_1, &h);
2838 /* Initialize constant pool hashing for a new function. */
2841 init_varasm_status (struct function *f)
2843 struct varasm_status *p;
2844 struct rtx_constant_pool *pool;
2846 p = ggc_alloc (sizeof (struct varasm_status));
2849 pool = ggc_alloc (sizeof (struct rtx_constant_pool));
2851 p->deferred_constants = 0;
2853 pool->const_rtx_htab = htab_create_ggc (31, const_desc_rtx_hash,
2854 const_desc_rtx_eq, NULL);
2855 pool->const_rtx_sym_htab = htab_create_ggc (31, const_desc_rtx_sym_hash,
2856 const_desc_rtx_sym_eq, NULL);
2857 pool->first = pool->last = NULL;
2861 /* Given a MINUS expression, simplify it if both sides
2862 include the same symbol. */
2865 simplify_subtraction (rtx x)
2867 rtx r = simplify_rtx (x);
2871 /* Given a constant rtx X, make (or find) a memory constant for its value
2872 and return a MEM rtx to refer to it in memory. */
2875 force_const_mem (enum machine_mode mode, rtx x)
2877 struct constant_descriptor_rtx *desc, tmp;
2878 struct rtx_constant_pool *pool = cfun->varasm->pool;
2885 /* If we're not allowed to drop X into the constant pool, don't. */
2886 if (targetm.cannot_force_const_mem (x))
2889 /* Lookup the value in the hashtable. */
2892 hash = const_rtx_hash (x);
2893 slot = htab_find_slot_with_hash (pool->const_rtx_htab, &tmp, hash, INSERT);
2896 /* If the constant was already present, return its memory. */
2898 return copy_rtx (desc->mem);
2900 /* Otherwise, create a new descriptor. */
2901 desc = ggc_alloc (sizeof (*desc));
2904 /* Align the location counter as required by EXP's data type. */
2905 align = GET_MODE_ALIGNMENT (mode == VOIDmode ? word_mode : mode);
2906 #ifdef CONSTANT_ALIGNMENT
2908 tree type = lang_hooks.types.type_for_mode (mode, 0);
2909 if (type != NULL_TREE)
2910 align = CONSTANT_ALIGNMENT (make_tree (type, x), align);
2914 pool->offset += (align / BITS_PER_UNIT) - 1;
2915 pool->offset &= ~ ((align / BITS_PER_UNIT) - 1);
2918 desc->constant = tmp.constant;
2919 desc->offset = pool->offset;
2922 desc->align = align;
2923 desc->labelno = const_labelno;
2926 pool->offset += GET_MODE_SIZE (mode);
2928 pool->last->next = desc;
2930 pool->first = pool->last = desc;
2933 /* Create a string containing the label name, in LABEL. */
2934 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
2937 /* Construct the SYMBOL_REF. Make sure to mark it as belonging to
2938 the constants pool. */
2939 desc->sym = symbol = gen_rtx_SYMBOL_REF (Pmode, ggc_strdup (label));
2940 SYMBOL_REF_FLAGS (symbol) = SYMBOL_FLAG_LOCAL;
2941 CONSTANT_POOL_ADDRESS_P (symbol) = 1;
2942 current_function_uses_const_pool = 1;
2944 /* Insert the descriptor into the symbol cross-reference table too. */
2945 slot = htab_find_slot (pool->const_rtx_sym_htab, desc, INSERT);
2950 /* Construct the MEM. */
2951 desc->mem = def = gen_rtx_MEM (mode, symbol);
2952 set_mem_attributes (def, lang_hooks.types.type_for_mode (mode, 0), 1);
2953 RTX_UNCHANGING_P (def) = 1;
2955 /* If we're dropping a label to the constant pool, make sure we
2957 if (GET_CODE (x) == LABEL_REF)
2958 LABEL_PRESERVE_P (XEXP (x, 0)) = 1;
2960 return copy_rtx (def);
2963 /* Given a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true, return a pointer to
2964 the corresponding constant_descriptor_rtx structure. */
2966 static struct constant_descriptor_rtx *
2967 find_pool_constant (struct rtx_constant_pool *pool, rtx sym)
2969 struct constant_descriptor_rtx tmp;
2971 return htab_find (pool->const_rtx_sym_htab, &tmp);
2974 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
2977 get_pool_constant (rtx addr)
2979 return find_pool_constant (cfun->varasm->pool, addr)->constant;
2982 /* Given a constant pool SYMBOL_REF, return the corresponding constant
2983 and whether it has been output or not. */
2986 get_pool_constant_mark (rtx addr, bool *pmarked)
2988 struct constant_descriptor_rtx *desc;
2990 desc = find_pool_constant (cfun->varasm->pool, addr);
2991 *pmarked = (desc->mark != 0);
2992 return desc->constant;
2995 /* Likewise, but for the constant pool of a specific function. */
2998 get_pool_constant_for_function (struct function *f, rtx addr)
3000 return find_pool_constant (f->varasm->pool, addr)->constant;
3003 /* Similar, return the mode. */
3006 get_pool_mode (rtx addr)
3008 return find_pool_constant (cfun->varasm->pool, addr)->mode;
3012 get_pool_mode_for_function (struct function *f, rtx addr)
3014 return find_pool_constant (f->varasm->pool, addr)->mode;
3017 /* Similar, return the offset in the constant pool. */
3020 get_pool_offset (rtx addr)
3022 return find_pool_constant (cfun->varasm->pool, addr)->offset;
3025 /* Return the size of the constant pool. */
3028 get_pool_size (void)
3030 return cfun->varasm->pool->offset;
3033 /* Worker function for output_constant_pool_1. Emit assembly for X
3034 in MODE with known alignment ALIGN. */
3037 output_constant_pool_2 (enum machine_mode mode, rtx x, unsigned int align)
3039 switch (GET_MODE_CLASS (mode))
3042 if (GET_CODE (x) != CONST_DOUBLE)
3047 REAL_VALUE_FROM_CONST_DOUBLE (r, x);
3048 assemble_real (r, mode, align);
3053 case MODE_PARTIAL_INT:
3054 assemble_integer (x, GET_MODE_SIZE (mode), align, 1);
3057 case MODE_VECTOR_FLOAT:
3058 case MODE_VECTOR_INT:
3061 enum machine_mode submode = GET_MODE_INNER (mode);
3062 unsigned int subalign = MIN (align, GET_MODE_BITSIZE (submode));
3064 if (GET_CODE (x) != CONST_VECTOR)
3066 units = CONST_VECTOR_NUNITS (x);
3068 for (i = 0; i < units; i++)
3070 rtx elt = CONST_VECTOR_ELT (x, i);
3071 output_constant_pool_2 (submode, elt, i ? subalign : align);
3081 /* Worker function for output_constant_pool. Emit POOL. */
3084 output_constant_pool_1 (struct constant_descriptor_rtx *desc)
3092 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3093 whose CODE_LABEL has been deleted. This can occur if a jump table
3094 is eliminated by optimization. If so, write a constant of zero
3095 instead. Note that this can also happen by turning the
3096 CODE_LABEL into a NOTE. */
3097 /* ??? This seems completely and utterly wrong. Certainly it's
3098 not true for NOTE_INSN_DELETED_LABEL, but I disbelieve proper
3099 functioning even with INSN_DELETED_P and friends. */
3102 switch (GET_CODE (x))
3105 if (GET_CODE (XEXP (x, 0)) != PLUS
3106 || GET_CODE (XEXP (XEXP (x, 0), 0)) != LABEL_REF)
3108 tmp = XEXP (XEXP (x, 0), 0);
3113 if (INSN_DELETED_P (tmp)
3115 && NOTE_LINE_NUMBER (tmp) == NOTE_INSN_DELETED))
3126 /* First switch to correct section. */
3127 targetm.asm_out.select_rtx_section (desc->mode, x, desc->align);
3129 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3130 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, desc->mode,
3131 desc->align, desc->labelno, done);
3134 assemble_align (desc->align);
3136 /* Output the label. */
3137 targetm.asm_out.internal_label (asm_out_file, "LC", desc->labelno);
3139 /* Output the data. */
3140 output_constant_pool_2 (desc->mode, x, desc->align);
3142 /* Make sure all constants in SECTION_MERGE and not SECTION_STRINGS
3143 sections have proper size. */
3144 if (desc->align > GET_MODE_BITSIZE (desc->mode)
3145 && in_section == in_named
3146 && get_named_section_flags (in_named_name) & SECTION_MERGE)
3147 assemble_align (desc->align);
3149 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3155 /* Given a SYMBOL_REF CURRENT_RTX, mark it and all constants it refers
3156 to as used. Emit referenced deferred strings. This function can
3157 be used with for_each_rtx to mark all SYMBOL_REFs in an rtx. */
3160 mark_constant (rtx *current_rtx, void *data)
3162 struct rtx_constant_pool *pool = data;
3163 rtx x = *current_rtx;
3165 if (x == NULL_RTX || GET_CODE (x) != SYMBOL_REF)
3168 if (CONSTANT_POOL_ADDRESS_P (x))
3170 struct constant_descriptor_rtx *desc = find_pool_constant (pool, x);
3171 if (desc->mark == 0)
3174 for_each_rtx (&desc->constant, mark_constant, pool);
3177 else if (TREE_CONSTANT_POOL_ADDRESS_P (x))
3179 tree exp = SYMBOL_REF_DECL (x);
3180 if (!TREE_ASM_WRITTEN (exp))
3182 n_deferred_constants--;
3183 output_constant_def_contents (x);
3190 /* Look through appropriate parts of INSN, marking all entries in the
3191 constant pool which are actually being used. Entries that are only
3192 referenced by other constants are also marked as used. Emit
3193 deferred strings that are used. */
3196 mark_constants (struct rtx_constant_pool *pool, rtx insn)
3201 /* Insns may appear inside a SEQUENCE. Only check the patterns of
3202 insns, not any notes that may be attached. We don't want to mark
3203 a constant just because it happens to appear in a REG_EQUIV note. */
3204 if (GET_CODE (PATTERN (insn)) == SEQUENCE)
3206 rtx seq = PATTERN (insn);
3207 int i, n = XVECLEN (seq, 0);
3208 for (i = 0; i < n; ++i)
3210 rtx subinsn = XVECEXP (seq, 0, i);
3211 if (INSN_P (subinsn))
3212 for_each_rtx (&PATTERN (subinsn), mark_constant, pool);
3216 for_each_rtx (&PATTERN (insn), mark_constant, pool);
3219 /* Look through the instructions for this function, and mark all the
3220 entries in POOL which are actually being used. Emit deferred constants
3221 which have indeed been used. */
3224 mark_constant_pool (struct rtx_constant_pool *pool)
3228 if (pool->first == 0 && n_deferred_constants == 0)
3231 for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3232 mark_constants (pool, insn);
3234 for (link = current_function_epilogue_delay_list;
3236 link = XEXP (link, 1))
3237 mark_constants (pool, XEXP (link, 0));
3240 /* Write all the constants in the constant pool. */
3243 output_constant_pool (const char *fnname ATTRIBUTE_UNUSED,
3244 tree fndecl ATTRIBUTE_UNUSED)
3246 struct rtx_constant_pool *pool = cfun->varasm->pool;
3247 struct constant_descriptor_rtx *desc;
3249 /* It is possible for gcc to call force_const_mem and then to later
3250 discard the instructions which refer to the constant. In such a
3251 case we do not need to output the constant. */
3252 mark_constant_pool (pool);
3254 #ifdef ASM_OUTPUT_POOL_PROLOGUE
3255 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool->offset);
3258 for (desc = pool->first; desc ; desc = desc->next)
3259 output_constant_pool_1 (desc);
3261 #ifdef ASM_OUTPUT_POOL_EPILOGUE
3262 ASM_OUTPUT_POOL_EPILOGUE (asm_out_file, fnname, fndecl, pool->offset);
3266 /* Determine what kind of relocations EXP may need. */
3269 compute_reloc_for_constant (tree exp)
3271 int reloc = 0, reloc2;
3274 /* Give the front-end a chance to convert VALUE to something that
3275 looks more like a constant to the back-end. */
3276 exp = lang_hooks.expand_constant (exp);
3278 switch (TREE_CODE (exp))
3282 /* Go inside any operations that get_inner_reference can handle and see
3283 if what's inside is a constant: no need to do anything here for
3284 addresses of variables or functions. */
3285 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
3286 tem = TREE_OPERAND (tem, 0))
3289 if (TREE_PUBLIC (tem))
3296 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3297 reloc |= compute_reloc_for_constant (TREE_OPERAND (exp, 1));
3301 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3302 reloc2 = compute_reloc_for_constant (TREE_OPERAND (exp, 1));
3303 /* The difference of two local labels is computable at link time. */
3304 if (reloc == 1 && reloc2 == 1)
3312 case NON_LVALUE_EXPR:
3313 reloc = compute_reloc_for_constant (TREE_OPERAND (exp, 0));
3317 for (tem = CONSTRUCTOR_ELTS (exp); tem; tem = TREE_CHAIN (tem))
3318 if (TREE_VALUE (tem) != 0)
3319 reloc |= compute_reloc_for_constant (TREE_VALUE (tem));
3329 /* Find all the constants whose addresses are referenced inside of EXP,
3330 and make sure assembler code with a label has been output for each one.
3331 Indicate whether an ADDR_EXPR has been encountered. */
3334 output_addressed_constants (tree exp)
3338 /* Give the front-end a chance to convert VALUE to something that
3339 looks more like a constant to the back-end. */
3340 exp = lang_hooks.expand_constant (exp);
3342 switch (TREE_CODE (exp))
3346 /* Go inside any operations that get_inner_reference can handle and see
3347 if what's inside is a constant: no need to do anything here for
3348 addresses of variables or functions. */
3349 for (tem = TREE_OPERAND (exp, 0); handled_component_p (tem);
3350 tem = TREE_OPERAND (tem, 0))
3353 if (TREE_CODE_CLASS (TREE_CODE (tem)) == 'c'
3354 || TREE_CODE (tem) == CONSTRUCTOR)
3355 output_constant_def (tem, 0);
3360 output_addressed_constants (TREE_OPERAND (exp, 1));
3365 case NON_LVALUE_EXPR:
3366 output_addressed_constants (TREE_OPERAND (exp, 0));
3370 for (tem = CONSTRUCTOR_ELTS (exp); tem; tem = TREE_CHAIN (tem))
3371 if (TREE_VALUE (tem) != 0)
3372 output_addressed_constants (TREE_VALUE (tem));
3381 /* Return nonzero if VALUE is a valid constant-valued expression
3382 for use in initializing a static variable; one that can be an
3383 element of a "constant" initializer.
3385 Return null_pointer_node if the value is absolute;
3386 if it is relocatable, return the variable that determines the relocation.
3387 We assume that VALUE has been folded as much as possible;
3388 therefore, we do not need to check for such things as
3389 arithmetic-combinations of integers. */
3392 initializer_constant_valid_p (tree value, tree endtype)
3394 /* Give the front-end a chance to convert VALUE to something that
3395 looks more like a constant to the back-end. */
3396 value = lang_hooks.expand_constant (value);
3398 switch (TREE_CODE (value))
3401 if ((TREE_CODE (TREE_TYPE (value)) == UNION_TYPE
3402 || TREE_CODE (TREE_TYPE (value)) == RECORD_TYPE)
3403 && TREE_CONSTANT (value)
3404 && CONSTRUCTOR_ELTS (value))
3407 bool absolute = true;
3409 for (elt = CONSTRUCTOR_ELTS (value); elt; elt = TREE_CHAIN (elt))
3412 value = TREE_VALUE (elt);
3413 reloc = initializer_constant_valid_p (value, TREE_TYPE (value));
3416 if (reloc != null_pointer_node)
3419 /* For a non-absolute relocation, there is no single
3420 variable that can be "the variable that determines the
3422 return absolute ? null_pointer_node : error_mark_node;
3425 return TREE_STATIC (value) ? null_pointer_node : NULL_TREE;
3432 return null_pointer_node;
3436 return staticp (TREE_OPERAND (value, 0)) ? TREE_OPERAND (value, 0) : 0;
3438 case VIEW_CONVERT_EXPR:
3439 case NON_LVALUE_EXPR:
3440 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3444 /* Allow conversions between pointer types. */
3445 if (POINTER_TYPE_P (TREE_TYPE (value))
3446 && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3447 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3449 /* Allow conversions between real types. */
3450 if (FLOAT_TYPE_P (TREE_TYPE (value))
3451 && FLOAT_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3452 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3454 /* Allow length-preserving conversions between integer types. */
3455 if (INTEGRAL_TYPE_P (TREE_TYPE (value))
3456 && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0)))
3457 && (TYPE_PRECISION (TREE_TYPE (value))
3458 == TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0)))))
3459 return initializer_constant_valid_p (TREE_OPERAND (value, 0), endtype);
3461 /* Allow conversions between other integer types only if
3463 if (INTEGRAL_TYPE_P (TREE_TYPE (value))
3464 && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3466 tree inner = initializer_constant_valid_p (TREE_OPERAND (value, 0),
3468 if (inner == null_pointer_node)
3469 return null_pointer_node;
3473 /* Allow (int) &foo provided int is as wide as a pointer. */
3474 if (INTEGRAL_TYPE_P (TREE_TYPE (value))
3475 && POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0)))
3476 && (TYPE_PRECISION (TREE_TYPE (value))
3477 >= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0)))))
3478 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
3481 /* Likewise conversions from int to pointers, but also allow
3482 conversions from 0. */
3483 if ((POINTER_TYPE_P (TREE_TYPE (value))
3484 || TREE_CODE (TREE_TYPE (value)) == OFFSET_TYPE)
3485 && INTEGRAL_TYPE_P (TREE_TYPE (TREE_OPERAND (value, 0))))
3487 if (integer_zerop (TREE_OPERAND (value, 0)))
3488 return null_pointer_node;
3489 else if (TYPE_PRECISION (TREE_TYPE (value))
3490 <= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (value, 0))))
3491 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
3495 /* Allow conversions to struct or union types if the value
3497 if (TREE_CODE (TREE_TYPE (value)) == RECORD_TYPE
3498 || TREE_CODE (TREE_TYPE (value)) == UNION_TYPE)
3499 return initializer_constant_valid_p (TREE_OPERAND (value, 0),
3504 if (! INTEGRAL_TYPE_P (endtype)
3505 || TYPE_PRECISION (endtype) >= POINTER_SIZE)
3507 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0),
3509 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1),
3511 /* If either term is absolute, use the other terms relocation. */
3512 if (valid0 == null_pointer_node)
3514 if (valid1 == null_pointer_node)
3520 if (! INTEGRAL_TYPE_P (endtype)
3521 || TYPE_PRECISION (endtype) >= POINTER_SIZE)
3523 tree valid0 = initializer_constant_valid_p (TREE_OPERAND (value, 0),
3525 tree valid1 = initializer_constant_valid_p (TREE_OPERAND (value, 1),
3527 /* Win if second argument is absolute. */
3528 if (valid1 == null_pointer_node)
3530 /* Win if both arguments have the same relocation.
3531 Then the value is absolute. */
3532 if (valid0 == valid1 && valid0 != 0)
3533 return null_pointer_node;
3535 /* Since GCC guarantees that string constants are unique in the
3536 generated code, a subtraction between two copies of the same
3537 constant string is absolute. */
3538 if (valid0 && TREE_CODE (valid0) == STRING_CST &&
3539 valid1 && TREE_CODE (valid1) == STRING_CST &&
3540 TREE_STRING_POINTER (valid0) == TREE_STRING_POINTER (valid1))
3541 return null_pointer_node;
3544 /* Support differences between labels. */
3545 if (INTEGRAL_TYPE_P (endtype))
3548 op0 = TREE_OPERAND (value, 0);
3549 op1 = TREE_OPERAND (value, 1);
3551 /* Like STRIP_NOPS except allow the operand mode to widen.
3552 This works around a feature of fold that simplifies
3553 (int)(p1 - p2) to ((int)p1 - (int)p2) under the theory
3554 that the narrower operation is cheaper. */
3556 while (TREE_CODE (op0) == NOP_EXPR
3557 || TREE_CODE (op0) == CONVERT_EXPR
3558 || TREE_CODE (op0) == NON_LVALUE_EXPR)
3560 tree inner = TREE_OPERAND (op0, 0);
3561 if (inner == error_mark_node
3562 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
3563 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op0)))
3564 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
3569 while (TREE_CODE (op1) == NOP_EXPR
3570 || TREE_CODE (op1) == CONVERT_EXPR
3571 || TREE_CODE (op1) == NON_LVALUE_EXPR)
3573 tree inner = TREE_OPERAND (op1, 0);
3574 if (inner == error_mark_node
3575 || ! INTEGRAL_MODE_P (TYPE_MODE (TREE_TYPE (inner)))
3576 || (GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (op1)))
3577 > GET_MODE_SIZE (TYPE_MODE (TREE_TYPE (inner)))))
3582 if (TREE_CODE (op0) == ADDR_EXPR
3583 && TREE_CODE (TREE_OPERAND (op0, 0)) == LABEL_DECL
3584 && TREE_CODE (op1) == ADDR_EXPR
3585 && TREE_CODE (TREE_OPERAND (op1, 0)) == LABEL_DECL)
3586 return null_pointer_node;
3597 /* Output assembler code for constant EXP to FILE, with no label.
3598 This includes the pseudo-op such as ".int" or ".byte", and a newline.
3599 Assumes output_addressed_constants has been done on EXP already.
3601 Generate exactly SIZE bytes of assembler data, padding at the end
3602 with zeros if necessary. SIZE must always be specified.
3604 SIZE is important for structure constructors,
3605 since trailing members may have been omitted from the constructor.
3606 It is also important for initialization of arrays from string constants
3607 since the full length of the string constant might not be wanted.
3608 It is also needed for initialization of unions, where the initializer's
3609 type is just one member, and that may not be as long as the union.
3611 There a case in which we would fail to output exactly SIZE bytes:
3612 for a structure constructor that wants to produce more than SIZE bytes.
3613 But such constructors will never be generated for any possible input.
3615 ALIGN is the alignment of the data in bits. */
3618 output_constant (tree exp, unsigned HOST_WIDE_INT size, unsigned int align)
3620 enum tree_code code;
3621 unsigned HOST_WIDE_INT thissize;
3623 /* Some front-ends use constants other than the standard language-independent
3624 varieties, but which may still be output directly. Give the front-end a
3625 chance to convert EXP to a language-independent representation. */
3626 exp = lang_hooks.expand_constant (exp);
3628 if (size == 0 || flag_syntax_only)
3631 /* Eliminate any conversions since we'll be outputting the underlying
3633 while (TREE_CODE (exp) == NOP_EXPR || TREE_CODE (exp) == CONVERT_EXPR
3634 || TREE_CODE (exp) == NON_LVALUE_EXPR
3635 || TREE_CODE (exp) == VIEW_CONVERT_EXPR)
3636 exp = TREE_OPERAND (exp, 0);
3638 code = TREE_CODE (TREE_TYPE (exp));
3639 thissize = int_size_in_bytes (TREE_TYPE (exp));
3641 /* Allow a constructor with no elements for any data type.
3642 This means to fill the space with zeros. */
3643 if (TREE_CODE (exp) == CONSTRUCTOR && CONSTRUCTOR_ELTS (exp) == 0)
3645 assemble_zeros (size);
3649 if (TREE_CODE (exp) == FDESC_EXPR)
3651 #ifdef ASM_OUTPUT_FDESC
3652 HOST_WIDE_INT part = tree_low_cst (TREE_OPERAND (exp, 1), 0);
3653 tree decl = TREE_OPERAND (exp, 0);
3654 ASM_OUTPUT_FDESC (asm_out_file, decl, part);
3661 /* Now output the underlying data. If we've handling the padding, return.
3662 Otherwise, break and ensure SIZE is the size written. */
3670 case REFERENCE_TYPE:
3672 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
3673 EXPAND_INITIALIZER),
3674 MIN (size, thissize), align, 0))
3675 error ("initializer for integer value is too complicated");
3679 if (TREE_CODE (exp) != REAL_CST)
3680 error ("initializer for floating value is not a floating constant");
3682 assemble_real (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)), align);
3686 output_constant (TREE_REALPART (exp), thissize / 2, align);
3687 output_constant (TREE_IMAGPART (exp), thissize / 2,
3688 min_align (align, BITS_PER_UNIT * (thissize / 2)));
3693 if (TREE_CODE (exp) == CONSTRUCTOR)
3695 output_constructor (exp, size, align);
3698 else if (TREE_CODE (exp) == STRING_CST)
3700 thissize = MIN ((unsigned HOST_WIDE_INT)TREE_STRING_LENGTH (exp),
3702 assemble_string (TREE_STRING_POINTER (exp), thissize);
3704 else if (TREE_CODE (exp) == VECTOR_CST)
3708 unsigned int nalign;
3709 enum machine_mode inner;
3711 inner = TYPE_MODE (TREE_TYPE (TREE_TYPE (exp)));
3712 nalign = MIN (align, GET_MODE_ALIGNMENT (inner));
3714 elt_size = GET_MODE_SIZE (inner);
3716 link = TREE_VECTOR_CST_ELTS (exp);
3717 output_constant (TREE_VALUE (link), elt_size, align);
3718 while ((link = TREE_CHAIN (link)) != NULL)
3719 output_constant (TREE_VALUE (link), elt_size, nalign);
3727 if (TREE_CODE (exp) == CONSTRUCTOR)
3728 output_constructor (exp, size, align);
3734 if (TREE_CODE (exp) == INTEGER_CST)
3735 assemble_integer (expand_expr (exp, NULL_RTX,
3736 VOIDmode, EXPAND_INITIALIZER),
3737 thissize, align, 1);
3738 else if (TREE_CODE (exp) == CONSTRUCTOR)
3740 unsigned char *buffer = alloca (thissize);
3741 if (get_set_constructor_bytes (exp, buffer, thissize))
3743 assemble_string ((char *) buffer, thissize);
3746 error ("unknown set constructor type");
3756 if (size > thissize)
3757 assemble_zeros (size - thissize);
3761 /* Subroutine of output_constructor, used for computing the size of
3762 arrays of unspecified length. VAL must be a CONSTRUCTOR of an array
3763 type with an unspecified upper bound. */
3765 static unsigned HOST_WIDE_INT
3766 array_size_for_constructor (tree val)
3770 /* This code used to attempt to handle string constants that are not
3771 arrays of single-bytes, but nothing else does, so there's no point in
3773 if (TREE_CODE (val) == STRING_CST)
3774 return TREE_STRING_LENGTH (val);
3776 max_index = NULL_TREE;
3777 for (i = CONSTRUCTOR_ELTS (val); i; i = TREE_CHAIN (i))
3779 tree index = TREE_PURPOSE (i);
3781 if (TREE_CODE (index) == RANGE_EXPR)
3782 index = TREE_OPERAND (index, 1);
3783 if (max_index == NULL_TREE || tree_int_cst_lt (max_index, index))
3787 if (max_index == NULL_TREE)
3790 /* Compute the total number of array elements. */
3791 i = size_binop (MINUS_EXPR, convert (sizetype, max_index),
3793 TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (val)))));
3794 i = size_binop (PLUS_EXPR, i, convert (sizetype, integer_one_node));
3796 /* Multiply by the array element unit size to find number of bytes. */
3797 i = size_binop (MULT_EXPR, i, TYPE_SIZE_UNIT (TREE_TYPE (TREE_TYPE (val))));
3799 return tree_low_cst (i, 1);
3802 /* Subroutine of output_constant, used for CONSTRUCTORs (aggregate constants).
3803 Generate at least SIZE bytes, padding if necessary. */
3806 output_constructor (tree exp, unsigned HOST_WIDE_INT size,
3809 tree type = TREE_TYPE (exp);
3810 tree link, field = 0;
3812 /* Number of bytes output or skipped so far.
3813 In other words, current position within the constructor. */
3814 HOST_WIDE_INT total_bytes = 0;
3815 /* Nonzero means BYTE contains part of a byte, to be output. */
3816 int byte_buffer_in_use = 0;
3819 if (HOST_BITS_PER_WIDE_INT < BITS_PER_UNIT)
3822 if (TREE_CODE (type) == RECORD_TYPE)
3823 field = TYPE_FIELDS (type);
3825 if (TREE_CODE (type) == ARRAY_TYPE
3826 && TYPE_DOMAIN (type) != 0)
3827 min_index = TYPE_MIN_VALUE (TYPE_DOMAIN (type));
3829 /* As LINK goes through the elements of the constant,
3830 FIELD goes through the structure fields, if the constant is a structure.
3831 if the constant is a union, then we override this,
3832 by getting the field from the TREE_LIST element.
3833 But the constant could also be an array. Then FIELD is zero.
3835 There is always a maximum of one element in the chain LINK for unions
3836 (even if the initializer in a source program incorrectly contains
3838 for (link = CONSTRUCTOR_ELTS (exp);
3840 link = TREE_CHAIN (link),
3841 field = field ? TREE_CHAIN (field) : 0)
3843 tree val = TREE_VALUE (link);
3846 /* The element in a union constructor specifies the proper field
3848 if ((TREE_CODE (type) == RECORD_TYPE || TREE_CODE (type) == UNION_TYPE
3849 || TREE_CODE (type) == QUAL_UNION_TYPE)
3850 && TREE_PURPOSE (link) != 0)
3851 field = TREE_PURPOSE (link);
3853 else if (TREE_CODE (type) == ARRAY_TYPE)
3854 index = TREE_PURPOSE (link);
3856 #ifdef ASM_COMMENT_START
3857 if (field && flag_verbose_asm)
3858 fprintf (asm_out_file, "%s %s:\n",
3861 ? IDENTIFIER_POINTER (DECL_NAME (field))
3865 /* Eliminate the marker that makes a cast not be an lvalue. */
3869 if (index && TREE_CODE (index) == RANGE_EXPR)
3871 unsigned HOST_WIDE_INT fieldsize
3872 = int_size_in_bytes (TREE_TYPE (type));
3873 HOST_WIDE_INT lo_index = tree_low_cst (TREE_OPERAND (index, 0), 0);
3874 HOST_WIDE_INT hi_index = tree_low_cst (TREE_OPERAND (index, 1), 0);
3875 HOST_WIDE_INT index;
3876 unsigned int align2 = min_align (align, fieldsize * BITS_PER_UNIT);
3878 for (index = lo_index; index <= hi_index; index++)
3880 /* Output the element's initial value. */
3882 assemble_zeros (fieldsize);
3884 output_constant (val, fieldsize, align2);
3886 /* Count its size. */
3887 total_bytes += fieldsize;
3890 else if (field == 0 || !DECL_BIT_FIELD (field))
3892 /* An element that is not a bit-field. */
3894 unsigned HOST_WIDE_INT fieldsize;
3895 /* Since this structure is static,
3896 we know the positions are constant. */
3897 HOST_WIDE_INT pos = field ? int_byte_position (field) : 0;
3898 unsigned int align2;
3901 pos = (tree_low_cst (TYPE_SIZE_UNIT (TREE_TYPE (val)), 1)
3902 * (tree_low_cst (index, 0) - tree_low_cst (min_index, 0)));
3904 /* Output any buffered-up bit-fields preceding this element. */
3905 if (byte_buffer_in_use)
3907 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
3909 byte_buffer_in_use = 0;
3912 /* Advance to offset of this element.
3913 Note no alignment needed in an array, since that is guaranteed
3914 if each element has the proper size. */
3915 if ((field != 0 || index != 0) && pos != total_bytes)
3917 assemble_zeros (pos - total_bytes);
3921 /* Find the alignment of this element. */
3922 align2 = min_align (align, BITS_PER_UNIT * pos);
3924 /* Determine size this element should occupy. */
3929 /* If this is an array with an unspecified upper bound,
3930 the initializer determines the size. */
3931 /* ??? This ought to only checked if DECL_SIZE_UNIT is NULL,
3932 but we cannot do this until the deprecated support for
3933 initializing zero-length array members is removed. */
3934 if (TREE_CODE (TREE_TYPE (field)) == ARRAY_TYPE
3935 && TYPE_DOMAIN (TREE_TYPE (field))
3936 && ! TYPE_MAX_VALUE (TYPE_DOMAIN (TREE_TYPE (field))))
3938 fieldsize = array_size_for_constructor (val);
3939 /* Given a non-empty initialization, this field had
3941 if (fieldsize != 0 && TREE_CHAIN (field) != NULL_TREE)
3944 else if (DECL_SIZE_UNIT (field))
3946 /* ??? This can't be right. If the decl size overflows
3947 a host integer we will silently emit no data. */
3948 if (host_integerp (DECL_SIZE_UNIT (field), 1))
3949 fieldsize = tree_low_cst (DECL_SIZE_UNIT (field), 1);
3953 fieldsize = int_size_in_bytes (TREE_TYPE (type));
3955 /* Output the element's initial value. */
3957 assemble_zeros (fieldsize);
3959 output_constant (val, fieldsize, align2);
3961 /* Count its size. */
3962 total_bytes += fieldsize;
3964 else if (val != 0 && TREE_CODE (val) != INTEGER_CST)
3965 error ("invalid initial value for member `%s'",
3966 IDENTIFIER_POINTER (DECL_NAME (field)));
3969 /* Element that is a bit-field. */
3971 HOST_WIDE_INT next_offset = int_bit_position (field);
3972 HOST_WIDE_INT end_offset
3973 = (next_offset + tree_low_cst (DECL_SIZE (field), 1));
3976 val = integer_zero_node;
3978 /* If this field does not start in this (or, next) byte,
3980 if (next_offset / BITS_PER_UNIT != total_bytes)
3982 /* Output remnant of any bit field in previous bytes. */
3983 if (byte_buffer_in_use)
3985 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
3987 byte_buffer_in_use = 0;
3990 /* If still not at proper byte, advance to there. */
3991 if (next_offset / BITS_PER_UNIT != total_bytes)
3993 assemble_zeros (next_offset / BITS_PER_UNIT - total_bytes);
3994 total_bytes = next_offset / BITS_PER_UNIT;
3998 if (! byte_buffer_in_use)
4001 /* We must split the element into pieces that fall within
4002 separate bytes, and combine each byte with previous or
4003 following bit-fields. */
4005 /* next_offset is the offset n fbits from the beginning of
4006 the structure to the next bit of this element to be processed.
4007 end_offset is the offset of the first bit past the end of
4009 while (next_offset < end_offset)
4013 HOST_WIDE_INT value;
4014 HOST_WIDE_INT next_byte = next_offset / BITS_PER_UNIT;
4015 HOST_WIDE_INT next_bit = next_offset % BITS_PER_UNIT;
4017 /* Advance from byte to byte
4018 within this element when necessary. */
4019 while (next_byte != total_bytes)
4021 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4026 /* Number of bits we can process at once
4027 (all part of the same byte). */
4028 this_time = MIN (end_offset - next_offset,
4029 BITS_PER_UNIT - next_bit);
4030 if (BYTES_BIG_ENDIAN)
4032 /* On big-endian machine, take the most significant bits
4033 first (of the bits that are significant)
4034 and put them into bytes from the most significant end. */
4035 shift = end_offset - next_offset - this_time;
4037 /* Don't try to take a bunch of bits that cross
4038 the word boundary in the INTEGER_CST. We can
4039 only select bits from the LOW or HIGH part
4041 if (shift < HOST_BITS_PER_WIDE_INT
4042 && shift + this_time > HOST_BITS_PER_WIDE_INT)
4044 this_time = shift + this_time - HOST_BITS_PER_WIDE_INT;
4045 shift = HOST_BITS_PER_WIDE_INT;
4048 /* Now get the bits from the appropriate constant word. */
4049 if (shift < HOST_BITS_PER_WIDE_INT)
4050 value = TREE_INT_CST_LOW (val);
4051 else if (shift < 2 * HOST_BITS_PER_WIDE_INT)
4053 value = TREE_INT_CST_HIGH (val);
4054 shift -= HOST_BITS_PER_WIDE_INT;
4059 /* Get the result. This works only when:
4060 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
4061 byte |= (((value >> shift)
4062 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
4063 << (BITS_PER_UNIT - this_time - next_bit));
4067 /* On little-endian machines,
4068 take first the least significant bits of the value
4069 and pack them starting at the least significant
4070 bits of the bytes. */
4071 shift = next_offset - int_bit_position (field);
4073 /* Don't try to take a bunch of bits that cross
4074 the word boundary in the INTEGER_CST. We can
4075 only select bits from the LOW or HIGH part
4077 if (shift < HOST_BITS_PER_WIDE_INT
4078 && shift + this_time > HOST_BITS_PER_WIDE_INT)
4079 this_time = (HOST_BITS_PER_WIDE_INT - shift);
4081 /* Now get the bits from the appropriate constant word. */
4082 if (shift < HOST_BITS_PER_WIDE_INT)
4083 value = TREE_INT_CST_LOW (val);
4084 else if (shift < 2 * HOST_BITS_PER_WIDE_INT)
4086 value = TREE_INT_CST_HIGH (val);
4087 shift -= HOST_BITS_PER_WIDE_INT;
4092 /* Get the result. This works only when:
4093 1 <= this_time <= HOST_BITS_PER_WIDE_INT. */
4094 byte |= (((value >> shift)
4095 & (((HOST_WIDE_INT) 2 << (this_time - 1)) - 1))
4099 next_offset += this_time;
4100 byte_buffer_in_use = 1;
4105 if (byte_buffer_in_use)
4107 assemble_integer (GEN_INT (byte), 1, BITS_PER_UNIT, 1);
4111 if ((unsigned HOST_WIDE_INT)total_bytes < size)
4112 assemble_zeros (size - total_bytes);
4115 /* This TREE_LIST contains any weak symbol declarations waiting
4117 static GTY(()) tree weak_decls;
4119 /* Mark DECL as weak. */
4122 mark_weak (tree decl)
4124 DECL_WEAK (decl) = 1;
4126 if (DECL_RTL_SET_P (decl)
4127 && MEM_P (DECL_RTL (decl))
4128 && XEXP (DECL_RTL (decl), 0)
4129 && GET_CODE (XEXP (DECL_RTL (decl), 0)) == SYMBOL_REF)
4130 SYMBOL_REF_WEAK (XEXP (DECL_RTL (decl), 0)) = 1;
4133 /* Merge weak status between NEWDECL and OLDDECL. */
4136 merge_weak (tree newdecl, tree olddecl)
4138 if (DECL_WEAK (newdecl) == DECL_WEAK (olddecl))
4141 if (DECL_WEAK (newdecl))
4145 /* NEWDECL is weak, but OLDDECL is not. */
4147 /* If we already output the OLDDECL, we're in trouble; we can't
4148 go back and make it weak. This error cannot caught in
4149 declare_weak because the NEWDECL and OLDDECL was not yet
4150 been merged; therefore, TREE_ASM_WRITTEN was not set. */
4151 if (TREE_ASM_WRITTEN (olddecl))
4152 error ("%Jweak declaration of '%D' must precede definition",
4155 /* If we've already generated rtl referencing OLDDECL, we may
4156 have done so in a way that will not function properly with
4158 else if (TREE_USED (olddecl)
4159 && TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (olddecl)))
4160 warning ("%Jweak declaration of '%D' after first use results "
4161 "in unspecified behavior", newdecl, newdecl);
4165 /* We put the NEWDECL on the weak_decls list at some point.
4166 Replace it with the OLDDECL. */
4167 for (wd = weak_decls; wd; wd = TREE_CHAIN (wd))
4168 if (TREE_VALUE (wd) == newdecl)
4170 TREE_VALUE (wd) = olddecl;
4173 /* We may not find the entry on the list. If NEWDECL is a
4174 weak alias, then we will have already called
4175 globalize_decl to remove the entry; in that case, we do
4176 not need to do anything. */
4179 /* Make the OLDDECL weak; it's OLDDECL that we'll be keeping. */
4180 mark_weak (olddecl);
4183 /* OLDDECL was weak, but NEWDECL was not explicitly marked as
4184 weak. Just update NEWDECL to indicate that it's weak too. */
4185 mark_weak (newdecl);
4188 /* Declare DECL to be a weak symbol. */
4191 declare_weak (tree decl)
4193 if (! TREE_PUBLIC (decl))
4194 error ("%Jweak declaration of '%D' must be public", decl, decl);
4195 else if (TREE_CODE (decl) == FUNCTION_DECL && TREE_ASM_WRITTEN (decl))
4196 error ("%Jweak declaration of '%D' must precede definition", decl, decl);
4197 else if (SUPPORTS_WEAK)
4199 if (! DECL_WEAK (decl))
4200 weak_decls = tree_cons (NULL, decl, weak_decls);
4203 warning ("%Jweak declaration of '%D' not supported", decl, decl);
4208 /* Emit any pending weak declarations. */
4215 for (t = weak_decls; t; t = TREE_CHAIN (t))
4217 tree decl = TREE_VALUE (t);
4218 #if defined (ASM_WEAKEN_DECL) || defined (ASM_WEAKEN_LABEL)
4219 const char *const name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
4222 if (! TREE_USED (decl))
4225 #ifdef ASM_WEAKEN_DECL
4226 ASM_WEAKEN_DECL (asm_out_file, decl, name, NULL);
4228 #ifdef ASM_WEAKEN_LABEL
4229 ASM_WEAKEN_LABEL (asm_out_file, name);
4231 #ifdef ASM_OUTPUT_WEAK_ALIAS
4232 warning ("only weak aliases are supported in this configuration");
4240 /* Emit the assembly bits to indicate that DECL is globally visible. */
4243 globalize_decl (tree decl)
4245 const char *name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
4247 #if defined (ASM_WEAKEN_LABEL) || defined (ASM_WEAKEN_DECL)
4248 if (DECL_WEAK (decl))
4252 #ifdef ASM_WEAKEN_DECL
4253 ASM_WEAKEN_DECL (asm_out_file, decl, name, 0);
4255 ASM_WEAKEN_LABEL (asm_out_file, name);
4258 /* Remove this function from the pending weak list so that
4259 we do not emit multiple .weak directives for it. */
4260 for (p = &weak_decls; (t = *p) ; )
4262 if (DECL_ASSEMBLER_NAME (decl) == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
4263 *p = TREE_CHAIN (t);
4265 p = &TREE_CHAIN (t);
4269 #elif defined(ASM_MAKE_LABEL_LINKONCE)
4270 if (DECL_ONE_ONLY (decl))
4271 ASM_MAKE_LABEL_LINKONCE (asm_out_file, name);
4274 targetm.asm_out.globalize_label (asm_out_file, name);
4277 /* Emit an assembler directive to make the symbol for DECL an alias to
4278 the symbol for TARGET. */
4281 assemble_alias (tree decl, tree target ATTRIBUTE_UNUSED)
4285 /* We must force creation of DECL_RTL for debug info generation, even though
4286 we don't use it here. */
4287 make_decl_rtl (decl);
4289 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
4291 #ifdef ASM_OUTPUT_DEF
4292 /* Make name accessible from other files, if appropriate. */
4294 if (TREE_PUBLIC (decl))
4296 globalize_decl (decl);
4297 maybe_assemble_visibility (decl);
4300 #ifdef ASM_OUTPUT_DEF_FROM_DECLS
4301 ASM_OUTPUT_DEF_FROM_DECLS (asm_out_file, decl, target);
4303 ASM_OUTPUT_DEF (asm_out_file, name, IDENTIFIER_POINTER (target));
4305 #else /* !ASM_OUTPUT_DEF */
4306 #if defined (ASM_OUTPUT_WEAK_ALIAS) || defined (ASM_WEAKEN_DECL)
4307 if (DECL_WEAK (decl))
4310 #ifdef ASM_WEAKEN_DECL
4311 ASM_WEAKEN_DECL (asm_out_file, decl, name, IDENTIFIER_POINTER (target));
4313 ASM_OUTPUT_WEAK_ALIAS (asm_out_file, name, IDENTIFIER_POINTER (target));
4315 /* Remove this function from the pending weak list so that
4316 we do not emit multiple .weak directives for it. */
4317 for (p = &weak_decls; (t = *p) ; )
4318 if (DECL_ASSEMBLER_NAME (decl)
4319 == DECL_ASSEMBLER_NAME (TREE_VALUE (t)))
4320 *p = TREE_CHAIN (t);
4322 p = &TREE_CHAIN (t);
4325 warning ("only weak aliases are supported in this configuration");
4328 warning ("alias definitions not supported in this configuration; ignored");
4332 TREE_USED (decl) = 1;
4333 TREE_ASM_WRITTEN (decl) = 1;
4334 TREE_ASM_WRITTEN (DECL_ASSEMBLER_NAME (decl)) = 1;
4337 /* Emit an assembler directive to set symbol for DECL visibility to
4338 the visibility type VIS, which must not be VISIBILITY_DEFAULT. */
4341 default_assemble_visibility (tree decl, int vis)
4343 static const char * const visibility_types[] = {
4344 NULL, "internal", "hidden", "protected"
4347 const char *name, *type;
4349 name = (IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl)));
4350 type = visibility_types[vis];
4352 #ifdef HAVE_GAS_HIDDEN
4353 fprintf (asm_out_file, "\t.%s\t", type);
4354 assemble_name (asm_out_file, name);
4355 fprintf (asm_out_file, "\n");
4357 warning ("visibility attribute not supported in this configuration; ignored");
4361 /* A helper function to call assemble_visibility when needed for a decl. */
4364 maybe_assemble_visibility (tree decl)
4366 enum symbol_visibility vis = DECL_VISIBILITY (decl);
4368 if (vis != VISIBILITY_DEFAULT)
4369 targetm.asm_out.visibility (decl, vis);
4372 /* Returns 1 if the target configuration supports defining public symbols
4373 so that one of them will be chosen at link time instead of generating a
4374 multiply-defined symbol error, whether through the use of weak symbols or
4375 a target-specific mechanism for having duplicates discarded. */
4378 supports_one_only (void)
4380 if (SUPPORTS_ONE_ONLY)
4382 return SUPPORTS_WEAK;
4385 /* Set up DECL as a public symbol that can be defined in multiple
4386 translation units without generating a linker error. */
4389 make_decl_one_only (tree decl)
4391 if (TREE_CODE (decl) != VAR_DECL && TREE_CODE (decl) != FUNCTION_DECL)
4394 TREE_PUBLIC (decl) = 1;
4396 if (SUPPORTS_ONE_ONLY)
4398 #ifdef MAKE_DECL_ONE_ONLY
4399 MAKE_DECL_ONE_ONLY (decl);
4401 DECL_ONE_ONLY (decl) = 1;
4403 else if (TREE_CODE (decl) == VAR_DECL
4404 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node))
4405 DECL_COMMON (decl) = 1;
4406 else if (SUPPORTS_WEAK)
4407 DECL_WEAK (decl) = 1;
4413 init_varasm_once (void)
4415 in_named_htab = htab_create_ggc (31, in_named_entry_hash,
4416 in_named_entry_eq, NULL);
4417 const_desc_htab = htab_create_ggc (1009, const_desc_hash,
4418 const_desc_eq, NULL);
4420 const_alias_set = new_alias_set ();
4424 decl_tls_model (tree decl)
4426 enum tls_model kind;
4427 tree attr = lookup_attribute ("tls_model", DECL_ATTRIBUTES (decl));
4432 attr = TREE_VALUE (TREE_VALUE (attr));
4433 if (TREE_CODE (attr) != STRING_CST)
4435 if (!strcmp (TREE_STRING_POINTER (attr), "local-exec"))
4436 kind = TLS_MODEL_LOCAL_EXEC;
4437 else if (!strcmp (TREE_STRING_POINTER (attr), "initial-exec"))
4438 kind = TLS_MODEL_INITIAL_EXEC;
4439 else if (!strcmp (TREE_STRING_POINTER (attr), "local-dynamic"))
4440 kind = optimize ? TLS_MODEL_LOCAL_DYNAMIC : TLS_MODEL_GLOBAL_DYNAMIC;
4441 else if (!strcmp (TREE_STRING_POINTER (attr), "global-dynamic"))
4442 kind = TLS_MODEL_GLOBAL_DYNAMIC;
4448 is_local = targetm.binds_local_p (decl);
4452 kind = TLS_MODEL_LOCAL_EXEC;
4454 kind = TLS_MODEL_INITIAL_EXEC;
4456 /* Local dynamic is inefficient when we're not combining the
4457 parts of the address. */
4458 else if (optimize && is_local)
4459 kind = TLS_MODEL_LOCAL_DYNAMIC;
4461 kind = TLS_MODEL_GLOBAL_DYNAMIC;
4462 if (kind < flag_tls_default)
4463 kind = flag_tls_default;
4468 /* Select a set of attributes for section NAME based on the properties
4469 of DECL and whether or not RELOC indicates that DECL's initializer
4470 might contain runtime relocations.
4472 We make the section read-only and executable for a function decl,
4473 read-only for a const data decl, and writable for a non-const data decl. */
4476 default_section_type_flags (tree decl, const char *name, int reloc)
4478 return default_section_type_flags_1 (decl, name, reloc, flag_pic);
4482 default_section_type_flags_1 (tree decl, const char *name, int reloc,
4487 if (decl && TREE_CODE (decl) == FUNCTION_DECL)
4488 flags = SECTION_CODE;
4489 else if (decl && decl_readonly_section_1 (decl, reloc, shlib))
4491 else if (strcmp (name, UNLIKELY_EXECUTED_TEXT_SECTION_NAME) == 0)
4492 flags = SECTION_CODE;
4494 flags = SECTION_WRITE;
4496 if (decl && DECL_ONE_ONLY (decl))
4497 flags |= SECTION_LINKONCE;
4499 if (decl && TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl))
4500 flags |= SECTION_TLS | SECTION_WRITE;
4502 if (strcmp (name, ".bss") == 0
4503 || strncmp (name, ".bss.", 5) == 0
4504 || strncmp (name, ".gnu.linkonce.b.", 16) == 0
4505 || strcmp (name, ".sbss") == 0
4506 || strncmp (name, ".sbss.", 6) == 0
4507 || strncmp (name, ".gnu.linkonce.sb.", 17) == 0
4508 || strcmp (name, ".tbss") == 0
4509 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
4510 flags |= SECTION_BSS;
4512 if (strcmp (name, ".tdata") == 0
4513 || strcmp (name, ".tbss") == 0
4514 || strncmp (name, ".gnu.linkonce.td.", 17) == 0
4515 || strncmp (name, ".gnu.linkonce.tb.", 17) == 0)
4516 flags |= SECTION_TLS;
4518 /* These three sections have special ELF types. They are neither
4519 SHT_PROGBITS nor SHT_NOBITS, so when changing sections we don't
4520 want to print a section type (@progbits or @nobits). If someone
4521 is silly enough to emit code or TLS variables to one of these
4522 sections, then don't handle them specially. */
4523 if (!(flags & (SECTION_CODE | SECTION_BSS | SECTION_TLS))
4524 && (strcmp (name, ".init_array") == 0
4525 || strcmp (name, ".fini_array") == 0
4526 || strcmp (name, ".preinit_array") == 0))
4527 flags |= SECTION_NOTYPE;
4532 /* Output assembly to switch to section NAME with attribute FLAGS.
4533 Four variants for common object file formats. */
4536 default_no_named_section (const char *name ATTRIBUTE_UNUSED,
4537 unsigned int flags ATTRIBUTE_UNUSED)
4539 /* Some object formats don't support named sections at all. The
4540 front-end should already have flagged this as an error. */
4545 default_elf_asm_named_section (const char *name, unsigned int flags)
4547 char flagchars[10], *f = flagchars;
4549 if (! named_section_first_declaration (name))
4551 fprintf (asm_out_file, "\t.section\t%s\n", name);
4555 if (!(flags & SECTION_DEBUG))
4557 if (flags & SECTION_WRITE)
4559 if (flags & SECTION_CODE)
4561 if (flags & SECTION_SMALL)
4563 if (flags & SECTION_MERGE)
4565 if (flags & SECTION_STRINGS)
4567 if (flags & SECTION_TLS)
4571 fprintf (asm_out_file, "\t.section\t%s,\"%s\"", name, flagchars);
4573 if (!(flags & SECTION_NOTYPE))
4577 if (flags & SECTION_BSS)
4582 fprintf (asm_out_file, ",@%s", type);
4584 if (flags & SECTION_ENTSIZE)
4585 fprintf (asm_out_file, ",%d", flags & SECTION_ENTSIZE);
4588 putc ('\n', asm_out_file);
4592 default_coff_asm_named_section (const char *name, unsigned int flags)
4594 char flagchars[8], *f = flagchars;
4596 if (flags & SECTION_WRITE)
4598 if (flags & SECTION_CODE)
4602 fprintf (asm_out_file, "\t.section\t%s,\"%s\"\n", name, flagchars);
4606 default_pe_asm_named_section (const char *name, unsigned int flags)
4608 default_coff_asm_named_section (name, flags);
4610 if (flags & SECTION_LINKONCE)
4612 /* Functions may have been compiled at various levels of
4613 optimization so we can't use `same_size' here.
4614 Instead, have the linker pick one. */
4615 fprintf (asm_out_file, "\t.linkonce %s\n",
4616 (flags & SECTION_CODE ? "discard" : "same_size"));
4620 /* The lame default section selector. */
4623 default_select_section (tree decl, int reloc,
4624 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
4626 bool readonly = false;
4630 if (decl_readonly_section (decl, reloc))
4633 else if (TREE_CODE (decl) == CONSTRUCTOR)
4635 if (! ((flag_pic && reloc)
4636 || !TREE_READONLY (decl)
4637 || TREE_SIDE_EFFECTS (decl)
4638 || !TREE_CONSTANT (decl)))
4641 else if (TREE_CODE (decl) == STRING_CST)
4643 else if (! (flag_pic && reloc))
4647 readonly_data_section ();
4652 /* A helper function for default_elf_select_section and
4653 default_elf_unique_section. Categorizes the DECL. */
4655 enum section_category
4660 SECCAT_RODATA_MERGE_STR,
4661 SECCAT_RODATA_MERGE_STR_INIT,
4662 SECCAT_RODATA_MERGE_CONST,
4667 /* To optimize loading of shared programs, define following subsections
4669 _REL Contains data that has relocations, so they get grouped
4670 together and dynamic linker will visit fewer pages in memory.
4671 _RO Contains data that is otherwise read-only. This is useful
4672 with prelinking as most relocations won't be dynamically
4673 linked and thus stay read only.
4674 _LOCAL Marks data containing relocations only to local objects.
4675 These relocations will get fully resolved by prelinking. */
4677 SECCAT_DATA_REL_LOCAL,
4679 SECCAT_DATA_REL_RO_LOCAL,
4689 static enum section_category
4690 categorize_decl_for_section (tree, int, int);
4692 static enum section_category
4693 categorize_decl_for_section (tree decl, int reloc, int shlib)
4695 enum section_category ret;
4697 if (TREE_CODE (decl) == FUNCTION_DECL)
4699 else if (TREE_CODE (decl) == STRING_CST)
4701 if (flag_mudflap) /* or !flag_merge_constants */
4702 return SECCAT_RODATA;
4704 return SECCAT_RODATA_MERGE_STR;
4706 else if (TREE_CODE (decl) == VAR_DECL)
4708 if (DECL_INITIAL (decl) == NULL
4709 || DECL_INITIAL (decl) == error_mark_node
4710 || (flag_zero_initialized_in_bss
4711 /* Leave constant zeroes in .rodata so they can be shared. */
4712 && !TREE_READONLY (decl)
4713 && initializer_zerop (DECL_INITIAL (decl))))
4715 else if (! TREE_READONLY (decl)
4716 || TREE_SIDE_EFFECTS (decl)
4717 || ! TREE_CONSTANT (DECL_INITIAL (decl)))
4719 if (shlib && (reloc & 2))
4720 ret = SECCAT_DATA_REL;
4721 else if (shlib && reloc)
4722 ret = SECCAT_DATA_REL_LOCAL;
4726 else if (shlib && (reloc & 2))
4727 ret = SECCAT_DATA_REL_RO;
4728 else if (shlib && reloc)
4729 ret = SECCAT_DATA_REL_RO_LOCAL;
4730 else if (reloc || flag_merge_constants < 2)
4731 /* C and C++ don't allow different variables to share the same
4732 location. -fmerge-all-constants allows even that (at the
4733 expense of not conforming). */
4734 ret = SECCAT_RODATA;
4735 else if (TREE_CODE (DECL_INITIAL (decl)) == STRING_CST)
4736 ret = SECCAT_RODATA_MERGE_STR_INIT;
4738 ret = SECCAT_RODATA_MERGE_CONST;
4740 else if (TREE_CODE (decl) == CONSTRUCTOR)
4742 if ((shlib && reloc)
4743 || TREE_SIDE_EFFECTS (decl)
4744 || ! TREE_CONSTANT (decl))
4747 ret = SECCAT_RODATA;
4750 ret = SECCAT_RODATA;
4752 /* There are no read-only thread-local sections. */
4753 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl))
4755 /* Note that this would be *just* SECCAT_BSS, except that there's
4756 no concept of a read-only thread-local-data section. */
4757 if (ret == SECCAT_BSS
4758 || (flag_zero_initialized_in_bss
4759 && initializer_zerop (DECL_INITIAL (decl))))
4765 /* If the target uses small data sections, select it. */
4766 else if (targetm.in_small_data_p (decl))
4768 if (ret == SECCAT_BSS)
4770 else if (targetm.have_srodata_section && ret == SECCAT_RODATA)
4771 ret = SECCAT_SRODATA;
4780 decl_readonly_section (tree decl, int reloc)
4782 return decl_readonly_section_1 (decl, reloc, flag_pic);
4786 decl_readonly_section_1 (tree decl, int reloc, int shlib)
4788 switch (categorize_decl_for_section (decl, reloc, shlib))
4791 case SECCAT_RODATA_MERGE_STR:
4792 case SECCAT_RODATA_MERGE_STR_INIT:
4793 case SECCAT_RODATA_MERGE_CONST:
4794 case SECCAT_SRODATA:
4803 /* Select a section based on the above categorization. */
4806 default_elf_select_section (tree decl, int reloc,
4807 unsigned HOST_WIDE_INT align)
4809 default_elf_select_section_1 (decl, reloc, align, flag_pic);
4813 default_elf_select_section_1 (tree decl, int reloc,
4814 unsigned HOST_WIDE_INT align, int shlib)
4816 switch (categorize_decl_for_section (decl, reloc, shlib))
4819 /* We're not supposed to be called on FUNCTION_DECLs. */
4822 readonly_data_section ();
4824 case SECCAT_RODATA_MERGE_STR:
4825 mergeable_string_section (decl, align, 0);
4827 case SECCAT_RODATA_MERGE_STR_INIT:
4828 mergeable_string_section (DECL_INITIAL (decl), align, 0);
4830 case SECCAT_RODATA_MERGE_CONST:
4831 mergeable_constant_section (DECL_MODE (decl), align, 0);
4833 case SECCAT_SRODATA:
4834 named_section (NULL_TREE, ".sdata2", reloc);
4839 case SECCAT_DATA_REL:
4840 named_section (NULL_TREE, ".data.rel", reloc);
4842 case SECCAT_DATA_REL_LOCAL:
4843 named_section (NULL_TREE, ".data.rel.local", reloc);
4845 case SECCAT_DATA_REL_RO:
4846 named_section (NULL_TREE, ".data.rel.ro", reloc);
4848 case SECCAT_DATA_REL_RO_LOCAL:
4849 named_section (NULL_TREE, ".data.rel.ro.local", reloc);
4852 named_section (NULL_TREE, ".sdata", reloc);
4855 named_section (NULL_TREE, ".tdata", reloc);
4858 #ifdef BSS_SECTION_ASM_OP
4861 named_section (NULL_TREE, ".bss", reloc);
4865 named_section (NULL_TREE, ".sbss", reloc);
4868 named_section (NULL_TREE, ".tbss", reloc);
4875 /* Construct a unique section name based on the decl name and the
4876 categorization performed above. */
4879 default_unique_section (tree decl, int reloc)
4881 default_unique_section_1 (decl, reloc, flag_pic);
4885 default_unique_section_1 (tree decl, int reloc, int shlib)
4887 bool one_only = DECL_ONE_ONLY (decl);
4888 const char *prefix, *name;
4892 switch (categorize_decl_for_section (decl, reloc, shlib))
4895 prefix = one_only ? ".gnu.linkonce.t." : ".text.";
4898 case SECCAT_RODATA_MERGE_STR:
4899 case SECCAT_RODATA_MERGE_STR_INIT:
4900 case SECCAT_RODATA_MERGE_CONST:
4901 prefix = one_only ? ".gnu.linkonce.r." : ".rodata.";
4903 case SECCAT_SRODATA:
4904 prefix = one_only ? ".gnu.linkonce.s2." : ".sdata2.";
4907 case SECCAT_DATA_REL:
4908 case SECCAT_DATA_REL_LOCAL:
4909 case SECCAT_DATA_REL_RO:
4910 case SECCAT_DATA_REL_RO_LOCAL:
4911 prefix = one_only ? ".gnu.linkonce.d." : ".data.";
4914 prefix = one_only ? ".gnu.linkonce.s." : ".sdata.";
4917 prefix = one_only ? ".gnu.linkonce.b." : ".bss.";
4920 prefix = one_only ? ".gnu.linkonce.sb." : ".sbss.";
4923 prefix = one_only ? ".gnu.linkonce.td." : ".tdata.";
4926 prefix = one_only ? ".gnu.linkonce.tb." : ".tbss.";
4931 plen = strlen (prefix);
4933 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
4934 name = targetm.strip_name_encoding (name);
4935 nlen = strlen (name);
4937 string = alloca (nlen + plen + 1);
4938 memcpy (string, prefix, plen);
4939 memcpy (string + plen, name, nlen + 1);
4941 DECL_SECTION_NAME (decl) = build_string (nlen + plen, string);
4945 default_select_rtx_section (enum machine_mode mode ATTRIBUTE_UNUSED,
4947 unsigned HOST_WIDE_INT align ATTRIBUTE_UNUSED)
4950 switch (GET_CODE (x))
4962 readonly_data_section ();
4966 default_elf_select_rtx_section (enum machine_mode mode, rtx x,
4967 unsigned HOST_WIDE_INT align)
4969 /* ??? Handle small data here somehow. */
4972 switch (GET_CODE (x))
4976 named_section (NULL_TREE, ".data.rel.ro", 3);
4980 named_section (NULL_TREE, ".data.rel.ro.local", 1);
4987 mergeable_constant_section (mode, align, 0);
4990 /* Set the generally applicable flags on the SYMBOL_REF for EXP. */
4993 default_encode_section_info (tree decl, rtx rtl, int first ATTRIBUTE_UNUSED)
4998 /* Careful not to prod global register variables. */
5001 symbol = XEXP (rtl, 0);
5002 if (GET_CODE (symbol) != SYMBOL_REF)
5006 if (TREE_CODE (decl) == FUNCTION_DECL)
5007 flags |= SYMBOL_FLAG_FUNCTION;
5008 if (targetm.binds_local_p (decl))
5009 flags |= SYMBOL_FLAG_LOCAL;
5010 if (targetm.in_small_data_p (decl))
5011 flags |= SYMBOL_FLAG_SMALL;
5012 if (TREE_CODE (decl) == VAR_DECL && DECL_THREAD_LOCAL (decl))
5013 flags |= decl_tls_model (decl) << SYMBOL_FLAG_TLS_SHIFT;
5014 /* ??? Why is DECL_EXTERNAL ever set for non-PUBLIC names? Without
5015 being PUBLIC, the thing *must* be defined in this translation unit.
5016 Prevent this buglet from being propagated into rtl code as well. */
5017 if (DECL_P (decl) && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
5018 flags |= SYMBOL_FLAG_EXTERNAL;
5020 SYMBOL_REF_FLAGS (symbol) = flags;
5023 /* By default, we do nothing for encode_section_info, so we need not
5024 do anything but discard the '*' marker. */
5027 default_strip_name_encoding (const char *str)
5029 return str + (*str == '*');
5032 /* Assume ELF-ish defaults, since that's pretty much the most liberal
5033 wrt cross-module name binding. */
5036 default_binds_local_p (tree exp)
5038 return default_binds_local_p_1 (exp, flag_shlib);
5042 default_binds_local_p_1 (tree exp, int shlib)
5046 /* A non-decl is an entry in the constant pool. */
5049 /* Static variables are always local. */
5050 else if (! TREE_PUBLIC (exp))
5052 /* A variable is local if the user explicitly tells us so. */
5053 else if (DECL_VISIBILITY_SPECIFIED (exp) && DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
5055 /* Otherwise, variables defined outside this object may not be local. */
5056 else if (DECL_EXTERNAL (exp))
5058 /* Linkonce and weak data are never local. */
5059 else if (DECL_ONE_ONLY (exp) || DECL_WEAK (exp))
5061 /* If none of the above and visibility is not default, make local. */
5062 else if (DECL_VISIBILITY (exp) != VISIBILITY_DEFAULT)
5064 /* If PIC, then assume that any global name can be overridden by
5065 symbols resolved from other modules. */
5068 /* Uninitialized COMMON variable may be unified with symbols
5069 resolved from other modules. */
5070 else if (DECL_COMMON (exp)
5071 && (DECL_INITIAL (exp) == NULL
5072 || DECL_INITIAL (exp) == error_mark_node))
5074 /* Otherwise we're left with initialized (or non-common) global data
5075 which is of necessity defined locally. */
5082 /* Determine whether or not a pointer mode is valid. Assume defaults
5083 of ptr_mode or Pmode - can be overridden. */
5085 default_valid_pointer_mode (enum machine_mode mode)
5087 return (mode == ptr_mode || mode == Pmode);
5090 /* Default function to output code that will globalize a label. A
5091 target must define GLOBAL_ASM_OP or provide it's own function to
5092 globalize a label. */
5093 #ifdef GLOBAL_ASM_OP
5095 default_globalize_label (FILE * stream, const char *name)
5097 fputs (GLOBAL_ASM_OP, stream);
5098 assemble_name (stream, name);
5099 putc ('\n', stream);
5101 #endif /* GLOBAL_ASM_OP */
5103 /* Default function to output a label for unwind information. The
5104 default is to do nothing. A target that needs nonlocal labels for
5105 unwind information must provide its own function to do this. */
5107 default_emit_unwind_label (FILE * stream ATTRIBUTE_UNUSED,
5108 tree decl ATTRIBUTE_UNUSED,
5109 int for_eh ATTRIBUTE_UNUSED,
5110 int empty ATTRIBUTE_UNUSED)
5114 /* This is how to output an internal numbered label where PREFIX is
5115 the class of label and LABELNO is the number within the class. */
5118 default_internal_label (FILE *stream, const char *prefix,
5119 unsigned long labelno)
5121 char *const buf = alloca (40 + strlen (prefix));
5122 ASM_GENERATE_INTERNAL_LABEL (buf, prefix, labelno);
5123 ASM_OUTPUT_LABEL (stream, buf);
5126 /* This is the default behavior at the beginning of a file. It's
5127 controlled by two other target-hook toggles. */
5129 default_file_start (void)
5131 if (targetm.file_start_app_off && !flag_verbose_asm)
5132 fputs (ASM_APP_OFF, asm_out_file);
5134 if (targetm.file_start_file_directive)
5135 output_file_directive (asm_out_file, main_input_filename);
5138 /* This is a generic routine suitable for use as TARGET_ASM_FILE_END
5139 which emits a special section directive used to indicate whether or
5140 not this object file needs an executable stack. This is primarily
5141 a GNU extension to ELF but could be used on other targets. */
5143 int trampolines_created;
5146 file_end_indicate_exec_stack (void)
5148 unsigned int flags = SECTION_DEBUG;
5149 if (trampolines_created)
5150 flags |= SECTION_CODE;
5152 named_section_flags (".note.GNU-stack", flags);
5155 #include "gt-varasm.h"