1 /* Output variables, constants and external declarations, for GNU compiler.
2 Copyright (C) 1987, 1988, 1989, 1992 Free Software Foundation, Inc.
4 This file is part of GNU CC.
6 GNU CC is free software; you can redistribute it and/or modify
7 it under the terms of the GNU General Public License as published by
8 the Free Software Foundation; either version 2, or (at your option)
11 GNU CC is distributed in the hope that it will be useful,
12 but WITHOUT ANY WARRANTY; without even the implied warranty of
13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
14 GNU General Public License for more details.
16 You should have received a copy of the GNU General Public License
17 along with GNU CC; see the file COPYING. If not, write to
18 the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
21 /* This file handles generation of all the assembler code
22 *except* the instructions of a function.
23 This includes declarations of variables and their initial values.
25 We also output the assembler code for constants stored in memory
26 and are responsible for combining constants with the same value. */
30 /* #include <stab.h> */
37 #include "hard-reg-set.h"
44 #ifdef XCOFF_DEBUGGING_INFO
49 #define ASM_STABS_OP ".stabs"
52 /* This macro gets just the user-specified name
53 out of the string in a SYMBOL_REF. On most machines,
54 we discard the * if any and that's all. */
55 #ifndef STRIP_NAME_ENCODING
56 #define STRIP_NAME_ENCODING(VAR,SYMBOL_NAME) \
57 (VAR) = ((SYMBOL_NAME) + ((SYMBOL_NAME)[0] == '*'))
60 /* File in which assembler code is being written. */
62 extern FILE *asm_out_file;
64 /* The (assembler) name of the first globally-visible object output. */
65 char *first_global_object_name;
67 extern struct obstack *current_obstack;
68 extern struct obstack *saveable_obstack;
69 extern struct obstack permanent_obstack;
70 #define obstack_chunk_alloc xmalloc
72 /* Number for making the label on the next
73 constant that is stored in memory. */
77 /* Number for making the label on the next
78 static variable internal to a function. */
82 /* Nonzero if at least one function definition has been seen. */
83 static int function_defined;
85 extern FILE *asm_out_file;
87 static char *compare_constant_1 ();
88 static void record_constant_1 ();
89 void output_constant_pool ();
90 void assemble_name ();
91 int output_addressed_constants ();
92 void output_constant ();
93 void output_constructor ();
95 void readonly_data_section ();
99 static enum in_section {no_section, in_text, in_data, EXTRA_SECTIONS} in_section
102 static enum in_section {no_section, in_text, in_data} in_section
106 /* Define functions like text_section for any extra sections. */
107 #ifdef EXTRA_SECTION_FUNCTIONS
108 EXTRA_SECTION_FUNCTIONS
111 /* Tell assembler to switch to text section. */
116 if (in_section != in_text)
118 fprintf (asm_out_file, "%s\n", TEXT_SECTION_ASM_OP);
119 in_section = in_text;
123 /* Tell assembler to switch to data section. */
128 if (in_section != in_data)
130 if (flag_shared_data)
132 #ifdef SHARED_SECTION_ASM_OP
133 fprintf (asm_out_file, "%s\n", SHARED_SECTION_ASM_OP);
135 fprintf (asm_out_file, "%s\n", DATA_SECTION_ASM_OP);
139 fprintf (asm_out_file, "%s\n", DATA_SECTION_ASM_OP);
141 in_section = in_data;
145 /* Tell assembler to switch to read-only data section. This is normally
149 readonly_data_section ()
151 #ifdef READONLY_DATA_SECTION
152 READONLY_DATA_SECTION (); /* Note this can call data_section. */
158 /* Determine if we're in the text section. */
163 return in_section == in_text;
166 /* Create the rtl to represent a function, for a function definition.
167 DECL is a FUNCTION_DECL node which describes which function.
168 The rtl is stored into DECL. */
171 make_function_rtl (decl)
174 char *name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
176 /* Rename a nested function to avoid conflicts. */
177 if (decl_function_context (decl) != 0
178 && DECL_INITIAL (decl) != 0
179 && DECL_RTL (decl) == 0)
183 name = IDENTIFIER_POINTER (DECL_NAME (decl));
184 ASM_FORMAT_PRIVATE_NAME (label, name, var_labelno);
185 name = obstack_copy0 (saveable_obstack, label, strlen (label));
189 if (DECL_RTL (decl) == 0)
192 = gen_rtx (MEM, DECL_MODE (decl),
193 gen_rtx (SYMBOL_REF, Pmode, name));
195 /* Optionally set flags or add text to the name to record information
196 such as that it is a function name. If the name is changed, the macro
197 ASM_OUTPUT_LABELREF will have to know how to strip this information.
198 And if it finds a * at the beginning after doing so, it must handle
200 #ifdef ENCODE_SECTION_INFO
201 ENCODE_SECTION_INFO (decl);
205 /* Record at least one function has been defined. */
206 function_defined = 1;
209 /* Given NAME, a putative register name, discard any customary prefixes. */
212 strip_reg_name (name)
215 #ifdef REGISTER_PREFIX
216 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
217 name += strlen (REGISTER_PREFIX);
219 if (name[0] == '%' || name[0] == '#')
224 /* Decode an `asm' spec for a declaration as a register name.
225 Return the register number, or -1 if nothing specified,
226 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
227 or -3 if ASMSPEC is `cc' and is not recognized,
228 or -4 if ASMSPEC is `memory' and is not recognized.
229 Accept an exact spelling or a decimal number.
230 Prefixes such as % are optional. */
233 decode_reg_name (asmspec)
240 /* Get rid of confusing prefixes. */
241 asmspec = strip_reg_name (asmspec);
243 /* Allow a decimal number as a "register name". */
244 for (i = strlen (asmspec) - 1; i >= 0; i--)
245 if (! (asmspec[i] >= '0' && asmspec[i] <= '9'))
247 if (asmspec[0] != 0 && i < 0)
250 if (i < FIRST_PSEUDO_REGISTER && i >= 0)
256 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
258 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
261 #ifdef ADDITIONAL_REGISTER_NAMES
263 static struct { char *name; int number; } table[]
264 = ADDITIONAL_REGISTER_NAMES;
266 for (i = 0; i < sizeof (table) / sizeof (table[0]); i++)
267 if (! strcmp (asmspec, table[i].name))
268 return table[i].number;
270 #endif /* ADDITIONAL_REGISTER_NAMES */
272 if (!strcmp (asmspec, "memory"))
275 if (!strcmp (asmspec, "cc"))
284 /* Create the DECL_RTL for a declaration for a static or external variable
285 or static or external function.
286 ASMSPEC, if not 0, is the string which the user specified
287 as the assembler symbol name.
288 TOP_LEVEL is nonzero if this is a file-scope variable.
290 This is never called for PARM_DECL nodes. */
293 make_decl_rtl (decl, asmspec, top_level)
299 int reg_number = decode_reg_name (asmspec);
301 if (DECL_ASSEMBLER_NAME (decl) != NULL_TREE)
302 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
304 if (reg_number == -2)
306 /* ASMSPEC is given, and not the name of a register. */
307 name = (char *) obstack_alloc (saveable_obstack,
308 strlen (asmspec) + 2);
310 strcpy (&name[1], asmspec);
313 /* For a duplicate declaration, we can be called twice on the
314 same DECL node. Don't alter the RTL already made
315 unless the old mode is wrong (which can happen when
316 the previous rtl was made when the type was incomplete). */
317 if (DECL_RTL (decl) == 0
318 || GET_MODE (DECL_RTL (decl)) != DECL_MODE (decl))
322 /* First detect errors in declaring global registers. */
323 if (DECL_REGISTER (decl) && reg_number == -1)
324 error_with_decl (decl,
325 "register name not specified for `%s'");
326 else if (DECL_REGISTER (decl) && reg_number < 0)
327 error_with_decl (decl,
328 "invalid register name for `%s'");
329 else if ((reg_number >= 0 || reg_number == -3) && ! DECL_REGISTER (decl))
330 error_with_decl (decl,
331 "register name given for non-register variable `%s'");
332 else if (DECL_REGISTER (decl) && TREE_CODE (decl) == FUNCTION_DECL)
333 error ("function declared `register'");
334 else if (DECL_REGISTER (decl) && TYPE_MODE (TREE_TYPE (decl)) == BLKmode)
335 error_with_decl (decl, "data type of `%s' isn't suitable for a register");
336 else if (DECL_REGISTER (decl)
337 && ! HARD_REGNO_MODE_OK (reg_number, TYPE_MODE (TREE_TYPE (decl))))
338 error_with_decl (decl, "register number for `%s' isn't suitable for the data type");
339 /* Now handle properly declared static register variables. */
340 else if (DECL_REGISTER (decl))
343 #if 0 /* yylex should print the warning for this */
345 pedwarn ("ANSI C forbids global register variables");
347 if (DECL_INITIAL (decl) != 0 && top_level)
349 DECL_INITIAL (decl) = 0;
350 error ("global register variable has initial value");
352 if (fixed_regs[reg_number] == 0
353 && function_defined && top_level)
354 error ("global register variable follows a function definition");
355 if (TREE_THIS_VOLATILE (decl))
356 warning ("volatile register variables don't work as you might wish");
358 /* If the user specified one of the eliminables registers here,
359 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
360 confused with that register and be eliminated. Although this
361 usage is somewhat suspect, we nevertheless use the following
362 kludge to avoid setting DECL_RTL to frame_pointer_rtx. */
365 = gen_rtx (REG, DECL_MODE (decl), FIRST_PSEUDO_REGISTER);
366 REGNO (DECL_RTL (decl)) = reg_number;
367 REG_USERVAR_P (DECL_RTL (decl)) = 1;
371 /* Make this register fixed, so not usable for anything else. */
372 nregs = HARD_REGNO_NREGS (reg_number, DECL_MODE (decl));
374 global_regs[reg_number + --nregs] = 1;
379 /* Now handle ordinary static variables and functions (in memory).
380 Also handle vars declared register invalidly. */
381 if (DECL_RTL (decl) == 0)
383 /* Can't use just the variable's own name for a variable
384 whose scope is less than the whole file.
385 Concatenate a distinguishing number. */
386 if (!top_level && !DECL_EXTERNAL (decl) && asmspec == 0)
390 ASM_FORMAT_PRIVATE_NAME (label, name, var_labelno);
391 name = obstack_copy0 (saveable_obstack, label, strlen (label));
395 DECL_RTL (decl) = gen_rtx (MEM, DECL_MODE (decl),
396 gen_rtx (SYMBOL_REF, Pmode, name));
397 if (TREE_THIS_VOLATILE (decl)
398 || (flag_volatile_global && TREE_CODE (decl) == VAR_DECL
399 && TREE_PUBLIC (decl)))
400 MEM_VOLATILE_P (DECL_RTL (decl)) = 1;
401 if (TREE_READONLY (decl))
402 RTX_UNCHANGING_P (DECL_RTL (decl)) = 1;
403 MEM_IN_STRUCT_P (DECL_RTL (decl))
404 = (TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE
405 || TREE_CODE (TREE_TYPE (decl)) == RECORD_TYPE
406 || TREE_CODE (TREE_TYPE (decl)) == UNION_TYPE
407 || TREE_CODE (TREE_TYPE (decl)) == QUAL_UNION_TYPE);
409 /* Optionally set flags or add text to the name to record information
410 such as that it is a function name.
411 If the name is changed, the macro ASM_OUTPUT_LABELREF
412 will have to know how to strip this information.
413 And if it finds a * at the beginning after doing so,
414 it must handle that too. */
415 #ifdef ENCODE_SECTION_INFO
416 ENCODE_SECTION_INFO (decl);
422 /* Make the rtl for variable VAR be volatile.
423 Use this only for static variables. */
426 make_var_volatile (var)
429 if (GET_CODE (DECL_RTL (var)) != MEM)
432 MEM_VOLATILE_P (DECL_RTL (var)) = 1;
435 /* Output a string of literal assembler code
436 for an `asm' keyword used between functions. */
439 assemble_asm (string)
444 if (TREE_CODE (string) == ADDR_EXPR)
445 string = TREE_OPERAND (string, 0);
447 fprintf (asm_out_file, "\t%s\n", TREE_STRING_POINTER (string));
450 #if 0 /* This should no longer be needed, because
451 flag_gnu_linker should be 0 on these systems,
452 which should prevent any output
453 if ASM_OUTPUT_CONSTRUCTOR and ASM_OUTPUT_DESTRUCTOR are absent. */
454 #if !(defined(DBX_DEBUGGING_INFO) && !defined(FASCIST_ASSEMBLER))
455 #ifndef ASM_OUTPUT_CONSTRUCTOR
456 #define ASM_OUTPUT_CONSTRUCTOR(file, name)
458 #ifndef ASM_OUTPUT_DESTRUCTOR
459 #define ASM_OUTPUT_DESTRUCTOR(file, name)
464 /* Record an element in the table of global destructors.
465 How this is done depends on what sort of assembler and linker
468 NAME should be the name of a global function to be called
469 at exit time. This name is output using assemble_name. */
472 assemble_destructor (name)
475 #ifdef ASM_OUTPUT_DESTRUCTOR
476 ASM_OUTPUT_DESTRUCTOR (asm_out_file, name);
480 /* Now tell GNU LD that this is part of the static destructor set. */
481 /* This code works for any machine provided you use GNU as/ld. */
482 fprintf (asm_out_file, "%s \"___DTOR_LIST__\",22,0,0,", ASM_STABS_OP);
483 assemble_name (asm_out_file, name);
484 fputc ('\n', asm_out_file);
489 /* Likewise for global constructors. */
492 assemble_constructor (name)
495 #ifdef ASM_OUTPUT_CONSTRUCTOR
496 ASM_OUTPUT_CONSTRUCTOR (asm_out_file, name);
500 /* Now tell GNU LD that this is part of the static constructor set. */
501 /* This code works for any machine provided you use GNU as/ld. */
502 fprintf (asm_out_file, "%s \"___CTOR_LIST__\",22,0,0,", ASM_STABS_OP);
503 assemble_name (asm_out_file, name);
504 fputc ('\n', asm_out_file);
509 /* Likewise for entries we want to record for garbage collection.
510 Garbage collection is still under development. */
513 assemble_gc_entry (name)
516 #ifdef ASM_OUTPUT_GC_ENTRY
517 ASM_OUTPUT_GC_ENTRY (asm_out_file, name);
521 /* Now tell GNU LD that this is part of the static constructor set. */
522 fprintf (asm_out_file, "%s \"___PTR_LIST__\",22,0,0,", ASM_STABS_OP);
523 assemble_name (asm_out_file, name);
524 fputc ('\n', asm_out_file);
529 /* Output assembler code for the constant pool of a function and associated
530 with defining the name of the function. DECL describes the function.
531 NAME is the function's name. For the constant pool, we use the current
532 constant pool data. */
535 assemble_start_function (decl, fnname)
541 /* The following code does not need preprocessing in the assembler. */
545 output_constant_pool (fnname, decl);
550 /* Tell assembler to move to target machine's alignment for functions. */
551 align = floor_log2 (FUNCTION_BOUNDARY / BITS_PER_UNIT);
553 ASM_OUTPUT_ALIGN (asm_out_file, align);
555 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
556 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
559 #ifdef SDB_DEBUGGING_INFO
560 /* Output SDB definition of the function. */
561 if (write_symbols == SDB_DEBUG)
562 sdbout_mark_begin_function ();
565 #ifdef DBX_DEBUGGING_INFO
566 /* Output DBX definition of the function. */
567 if (write_symbols == DBX_DEBUG)
568 dbxout_begin_function (decl);
571 /* Make function name accessible from other files, if appropriate. */
573 if (TREE_PUBLIC (decl))
575 if (!first_global_object_name)
576 STRIP_NAME_ENCODING (first_global_object_name, fnname);
577 ASM_GLOBALIZE_LABEL (asm_out_file, fnname);
580 /* Do any machine/system dependent processing of the function name */
581 #ifdef ASM_DECLARE_FUNCTION_NAME
582 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
584 /* Standard thing is just output label for the function. */
585 ASM_OUTPUT_LABEL (asm_out_file, fnname);
586 #endif /* ASM_DECLARE_FUNCTION_NAME */
589 /* Output assembler code associated with defining the size of the
590 function. DECL describes the function. NAME is the function's name. */
593 assemble_end_function (decl, fnname)
597 #ifdef ASM_DECLARE_FUNCTION_SIZE
598 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
602 /* Assemble code to leave SIZE bytes of zeros. */
605 assemble_zeros (size)
608 #ifdef ASM_NO_SKIP_IN_TEXT
609 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
610 so we must output 0s explicitly in the text section. */
611 if (ASM_NO_SKIP_IN_TEXT && in_text_section ())
615 for (i = 0; i < size - 20; i += 20)
618 fprintf (asm_out_file,
619 "%s 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0\n", ASM_BYTE_OP);
621 fprintf (asm_out_file,
622 "\tbyte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0\n");
628 fprintf (asm_out_file, "%s 0", ASM_BYTE_OP);
630 fprintf (asm_out_file, "\tbyte 0");
633 for (; i < size; i++)
634 fprintf (asm_out_file, ",0");
635 fprintf (asm_out_file, "\n");
641 ASM_OUTPUT_SKIP (asm_out_file, size);
644 /* Assemble a string constant with the specified C string as contents. */
647 assemble_string (p, size)
655 /* If the string is very long, split it up. */
659 int thissize = size - pos;
660 if (thissize > maximum)
663 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
670 /* Assemble everything that is needed for a variable or function declaration.
671 Not used for automatic variables, and not used for function definitions.
672 Should not be called for variables of incomplete structure type.
674 TOP_LEVEL is nonzero if this variable has file scope.
675 AT_END is nonzero if this is the special handling, at end of compilation,
676 to define things that have had only tentative definitions. */
679 assemble_variable (decl, top_level, at_end)
689 if (GET_CODE (DECL_RTL (decl)) == REG)
691 /* Do output symbol info for global register variables, but do nothing
694 if (TREE_ASM_WRITTEN (decl))
696 TREE_ASM_WRITTEN (decl) = 1;
698 #if defined (DBX_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
699 /* File-scope global variables are output here. */
700 if ((write_symbols == DBX_DEBUG || write_symbols == XCOFF_DEBUG)
702 dbxout_symbol (decl, 0);
704 #ifdef SDB_DEBUGGING_INFO
705 if (write_symbols == SDB_DEBUG && top_level
706 /* Leave initialized global vars for end of compilation;
707 see comment in compile_file. */
708 && (TREE_PUBLIC (decl) == 0 || DECL_INITIAL (decl) == 0))
709 sdbout_symbol (decl, 0);
712 /* Don't output any DWARF debugging information for variables here.
713 In the case of local variables, the information for them is output
714 when we do our recursive traversal of the tree representation for
715 the entire containing function. In the case of file-scope variables,
716 we output information for all of them at the very end of compilation
717 while we are doing our final traversal of the chain of file-scope
723 /* Normally no need to say anything here for external references,
724 since assemble_external is called by the langauge-specific code
725 when a declaration is first seen. */
727 if (DECL_EXTERNAL (decl))
730 /* Output no assembler code for a function declaration.
731 Only definitions of functions output anything. */
733 if (TREE_CODE (decl) == FUNCTION_DECL)
736 /* If type was incomplete when the variable was declared,
737 see if it is complete now. */
739 if (DECL_SIZE (decl) == 0)
740 layout_decl (decl, 0);
742 /* Still incomplete => don't allocate it; treat the tentative defn
743 (which is what it must have been) as an `extern' reference. */
745 if (DECL_SIZE (decl) == 0)
747 error_with_file_and_line (DECL_SOURCE_FILE (decl),
748 DECL_SOURCE_LINE (decl),
749 "storage size of `%s' isn't known",
750 IDENTIFIER_POINTER (DECL_NAME (decl)));
754 /* The first declaration of a variable that comes through this function
755 decides whether it is global (in C, has external linkage)
756 or local (in C, has internal linkage). So do nothing more
757 if this function has already run. */
759 if (TREE_ASM_WRITTEN (decl))
762 TREE_ASM_WRITTEN (decl) = 1;
764 #ifdef DBX_DEBUGGING_INFO
765 /* File-scope global variables are output here. */
766 if (write_symbols == DBX_DEBUG && top_level)
767 dbxout_symbol (decl, 0);
769 #ifdef SDB_DEBUGGING_INFO
770 if (write_symbols == SDB_DEBUG && top_level
771 /* Leave initialized global vars for end of compilation;
772 see comment in compile_file. */
773 && (TREE_PUBLIC (decl) == 0 || DECL_INITIAL (decl) == 0))
774 sdbout_symbol (decl, 0);
777 /* Don't output any DWARF debugging information for variables here.
778 In the case of local variables, the information for them is output
779 when we do our recursive traversal of the tree representation for
780 the entire containing function. In the case of file-scope variables,
781 we output information for all of them at the very end of compilation
782 while we are doing our final traversal of the chain of file-scope
785 /* If storage size is erroneously variable, just continue.
786 Error message was already made. */
788 if (TREE_CODE (DECL_SIZE (decl)) != INTEGER_CST)
793 /* This is better than explicit arithmetic, since it avoids overflow. */
794 size_tree = size_binop (CEIL_DIV_EXPR,
795 DECL_SIZE (decl), size_int (BITS_PER_UNIT));
797 if (TREE_INT_CST_HIGH (size_tree) != 0)
799 error_with_decl (decl, "size of variable `%s' is too large");
803 name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
805 /* Handle uninitialized definitions. */
807 /* ANSI specifies that a tentative definition which is not merged with
808 a non-tentative definition behaves exactly like a definition with an
809 initializer equal to zero. (Section 3.7.2)
810 -fno-common gives strict ANSI behavior. Usually you don't want it. */
812 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node))
814 int size = TREE_INT_CST_LOW (size_tree);
817 if (TREE_INT_CST_HIGH (size_tree) != 0)
818 error_with_decl (decl, "size of variable `%s' is too large");
819 /* Don't allocate zero bytes of common,
820 since that means "undefined external" in the linker. */
821 if (size == 0) rounded = 1;
822 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
823 so that each uninitialized object starts on such a boundary. */
824 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
825 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
826 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
828 if (flag_shared_data)
831 if (TREE_PUBLIC (decl))
833 #ifdef ASM_OUTPUT_SHARED_COMMON
834 if (flag_shared_data)
835 ASM_OUTPUT_SHARED_COMMON (asm_out_file, name, size, rounded);
838 #ifdef ASM_OUTPUT_ALIGNED_COMMON
839 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size,
842 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
847 #ifdef ASM_OUTPUT_SHARED_LOCAL
848 if (flag_shared_data)
849 ASM_OUTPUT_SHARED_LOCAL (asm_out_file, name, size, rounded);
852 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
853 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size,
856 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
862 /* Handle initialized definitions. */
864 /* First make the assembler name(s) global if appropriate. */
865 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
867 if (!first_global_object_name)
868 STRIP_NAME_ENCODING(first_global_object_name, name);
869 ASM_GLOBALIZE_LABEL (asm_out_file, name);
872 for (d = equivalents; d; d = TREE_CHAIN (d))
874 tree e = TREE_VALUE (d);
875 if (TREE_PUBLIC (e) && DECL_NAME (e))
876 ASM_GLOBALIZE_LABEL (asm_out_file,
877 XSTR (XEXP (DECL_RTL (e), 0), 0));
881 /* Output any data that we will need to use the address of. */
882 if (DECL_INITIAL (decl))
883 reloc = output_addressed_constants (DECL_INITIAL (decl));
885 /* Switch to the proper section for this data. */
886 #ifdef SELECT_SECTION
887 SELECT_SECTION (decl, reloc);
889 if (TREE_READONLY (decl)
890 && ! TREE_THIS_VOLATILE (decl)
891 && ! (flag_pic && reloc))
892 readonly_data_section ();
897 /* Compute and output the alignment of this data. */
899 align = DECL_ALIGN (decl);
900 /* Some object file formats have a maximum alignment which they support.
901 In particular, a.out format supports a maximum alignment of 4. */
902 #ifndef MAX_OFILE_ALIGNMENT
903 #define MAX_OFILE_ALIGNMENT BIGGEST_ALIGNMENT
905 if (align > MAX_OFILE_ALIGNMENT)
907 warning_with_decl (decl,
908 "alignment of `%s' is greater than maximum object file alignment");
909 align = MAX_OFILE_ALIGNMENT;
911 #ifdef DATA_ALIGNMENT
912 /* On some machines, it is good to increase alignment sometimes. */
913 align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
915 #ifdef CONSTANT_ALIGNMENT
916 if (DECL_INITIAL (decl))
917 align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
920 /* Reset the alignment in case we have made it tighter, so we can benefit
921 from it in get_pointer_alignment. */
922 DECL_ALIGN (decl) = align;
924 if (align > BITS_PER_UNIT)
925 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
927 /* Do any machine/system dependent processing of the object. */
928 #ifdef ASM_DECLARE_OBJECT_NAME
929 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
931 /* Standard thing is just output label for the object. */
932 ASM_OUTPUT_LABEL (asm_out_file, name);
933 #endif /* ASM_DECLARE_OBJECT_NAME */
936 for (d = equivalents; d; d = TREE_CHAIN (d))
938 tree e = TREE_VALUE (d);
939 ASM_OUTPUT_LABEL (asm_out_file, XSTR (XEXP (DECL_RTL (e), 0), 0));
943 if (DECL_INITIAL (decl))
944 /* Output the actual data. */
945 output_constant (DECL_INITIAL (decl),
946 int_size_in_bytes (TREE_TYPE (decl)));
948 /* Leave space for it. */
949 assemble_zeros (int_size_in_bytes (TREE_TYPE (decl)));
952 #ifdef XCOFF_DEBUGGING_INFO
953 /* Unfortunately, the IBM assembler cannot handle stabx before the actual
954 declaration. When something like ".stabx "aa:S-2",aa,133,0" is emitted
955 and `aa' hasn't been output yet, the assembler generates a stab entry with
956 a value of zero, in addition to creating an unnecessary external entry
957 for `aa'. Hence, we must postpone dbxout_symbol to here at the end. */
959 /* File-scope global variables are output here. */
960 if (write_symbols == XCOFF_DEBUG && top_level)
961 dbxout_symbol (decl, 0);
963 /* There must be a statement after a label. */
968 /* Output something to declare an external symbol to the assembler.
969 (Most assemblers don't need this, so we normally output nothing.)
970 Do nothing if DECL is not external. */
973 assemble_external (decl)
976 #ifdef ASM_OUTPUT_EXTERNAL
977 if (TREE_CODE_CLASS (TREE_CODE (decl)) == 'd'
978 && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
980 rtx rtl = DECL_RTL (decl);
982 if (GET_CODE (rtl) == MEM && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
983 && ! SYMBOL_REF_USED (XEXP (rtl, 0)))
985 /* Some systems do require some output. */
986 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
987 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
993 /* Similar, for calling a library function FUN. */
996 assemble_external_libcall (fun)
999 #ifdef ASM_OUTPUT_EXTERNAL_LIBCALL
1000 /* Declare library function name external when first used, if nec. */
1001 if (! SYMBOL_REF_USED (fun))
1003 SYMBOL_REF_USED (fun) = 1;
1004 ASM_OUTPUT_EXTERNAL_LIBCALL (asm_out_file, fun);
1009 /* Declare the label NAME global. */
1012 assemble_global (name)
1015 ASM_GLOBALIZE_LABEL (asm_out_file, name);
1018 /* Assemble a label named NAME. */
1021 assemble_label (name)
1024 ASM_OUTPUT_LABEL (asm_out_file, name);
1027 /* Output to FILE a reference to the assembler name of a C-level name NAME.
1028 If NAME starts with a *, the rest of NAME is output verbatim.
1029 Otherwise NAME is transformed in an implementation-defined way
1030 (usually by the addition of an underscore).
1031 Many macros in the tm file are defined to call this function. */
1034 assemble_name (file, name)
1039 fputs (&name[1], file);
1041 ASM_OUTPUT_LABELREF (file, name);
1044 /* Allocate SIZE bytes writable static space with a gensym name
1045 and return an RTX to refer to its address. */
1048 assemble_static_space (size)
1054 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1055 so that each uninitialized object starts on such a boundary. */
1056 int rounded = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
1057 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1058 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1061 if (flag_shared_data)
1065 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
1068 namestring = (char *) obstack_alloc (saveable_obstack,
1070 strcpy (namestring, name);
1072 x = gen_rtx (SYMBOL_REF, Pmode, namestring);
1073 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
1074 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
1076 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1081 /* Assemble the static constant template for function entry trampolines.
1082 This is done at most once per compilation.
1083 Returns an RTX for the address of the template. */
1086 assemble_trampoline_template ()
1092 /* By default, put trampoline templates in read-only data section. */
1094 #ifdef TRAMPOLINE_SECTION
1095 TRAMPOLINE_SECTION ();
1097 readonly_data_section ();
1100 /* Write the assembler code to define one. */
1101 align = floor_log2 (FUNCTION_BOUNDARY / BITS_PER_UNIT);
1103 ASM_OUTPUT_ALIGN (asm_out_file, align);
1105 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LTRAMP", 0);
1106 TRAMPOLINE_TEMPLATE (asm_out_file);
1108 /* Record the rtl to refer to it. */
1109 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
1111 = (char *) obstack_copy0 (&permanent_obstack, label, strlen (label));
1112 return gen_rtx (SYMBOL_REF, Pmode, name);
1115 /* Assemble the integer constant X into an object of SIZE bytes.
1116 X must be either a CONST_INT or CONST_DOUBLE.
1118 Return 1 if we were able to output the constant, otherwise 0. If FORCE is
1119 non-zero, abort if we can't output the constant. */
1122 assemble_integer (x, size, force)
1127 /* First try to use the standard 1, 2, 4, 8, and 16 byte
1128 ASM_OUTPUT... macros. */
1132 #ifdef ASM_OUTPUT_CHAR
1134 ASM_OUTPUT_CHAR (asm_out_file, x);
1138 #ifdef ASM_OUTPUT_SHORT
1140 ASM_OUTPUT_SHORT (asm_out_file, x);
1144 #ifdef ASM_OUTPUT_INT
1146 ASM_OUTPUT_INT (asm_out_file, x);
1150 #ifdef ASM_OUTPUT_DOUBLE_INT
1152 ASM_OUTPUT_DOUBLE_INT (asm_out_file, x);
1156 #ifdef ASM_OUTPUT_QUADRUPLE_INT
1158 ASM_OUTPUT_QUADRUPLE_INT (asm_out_file, x);
1163 /* If we couldn't do it that way, there are two other possibilities: First,
1164 if the machine can output an explicit byte and this is a 1 byte constant,
1165 we can use ASM_OUTPUT_BYTE. */
1167 #ifdef ASM_OUTPUT_BYTE
1168 if (size == 1 && GET_CODE (x) == CONST_INT)
1170 ASM_OUTPUT_BYTE (asm_out_file, INTVAL (x));
1175 /* Finally, if SIZE is larger than a single word, try to output the constant
1176 one word at a time. */
1178 if (size > UNITS_PER_WORD)
1181 enum machine_mode mode
1182 = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
1185 for (i = 0; i < size / UNITS_PER_WORD; i++)
1187 word = operand_subword (x, i, 0, mode);
1192 if (! assemble_integer (word, UNITS_PER_WORD, 0))
1196 if (i == size / UNITS_PER_WORD)
1198 /* If we output at least one word and then could not finish,
1199 there is no valid way to continue. */
1210 /* Assemble the floating-point constant D into an object of size MODE. */
1213 assemble_real (d, mode)
1215 enum machine_mode mode;
1217 jmp_buf output_constant_handler;
1219 if (setjmp (output_constant_handler))
1221 error ("floating point trap outputting a constant");
1222 #ifdef REAL_IS_NOT_DOUBLE
1223 bzero (&d, sizeof d);
1230 set_float_handler (output_constant_handler);
1234 #ifdef ASM_OUTPUT_BYTE_FLOAT
1236 ASM_OUTPUT_BYTE_FLOAT (asm_out_file, d);
1239 #ifdef ASM_OUTPUT_SHORT_FLOAT
1241 ASM_OUTPUT_SHORT_FLOAT (asm_out_file, d);
1244 #ifdef ASM_OUTPUT_FLOAT
1246 ASM_OUTPUT_FLOAT (asm_out_file, d);
1250 #ifdef ASM_OUTPUT_DOUBLE
1252 ASM_OUTPUT_DOUBLE (asm_out_file, d);
1256 #ifdef ASM_OUTPUT_LONG_DOUBLE
1259 ASM_OUTPUT_LONG_DOUBLE (asm_out_file, d);
1267 set_float_handler (NULL_PTR);
1270 /* Here we combine duplicate floating constants to make
1271 CONST_DOUBLE rtx's, and force those out to memory when necessary. */
1273 /* Chain of all CONST_DOUBLE rtx's constructed for the current function.
1274 They are chained through the CONST_DOUBLE_CHAIN.
1275 A CONST_DOUBLE rtx has CONST_DOUBLE_MEM != cc0_rtx iff it is on this chain.
1276 In that case, CONST_DOUBLE_MEM is either a MEM,
1277 or const0_rtx if no MEM has been made for this CONST_DOUBLE yet.
1279 (CONST_DOUBLE_MEM is used only for top-level functions.
1280 See force_const_mem for explanation.) */
1282 static rtx const_double_chain;
1284 /* Return a CONST_DOUBLE for a value specified as a pair of ints.
1285 For an integer, I0 is the low-order word and I1 is the high-order word.
1286 For a real number, I0 is the word with the low address
1287 and I1 is the word with the high address. */
1290 immed_double_const (i0, i1, mode)
1291 HOST_WIDE_INT i0, i1;
1292 enum machine_mode mode;
1295 int in_current_obstack;
1297 if (GET_MODE_CLASS (mode) == MODE_INT
1298 || GET_MODE_CLASS (mode) == MODE_PARTIAL_INT)
1300 /* We clear out all bits that don't belong in MODE, unless they and our
1301 sign bit are all one. So we get either a reasonable negative value
1302 or a reasonable unsigned value for this mode. */
1303 int width = GET_MODE_BITSIZE (mode);
1304 if (width < HOST_BITS_PER_WIDE_INT
1305 && ((i0 & ((HOST_WIDE_INT) (-1) << (width - 1)))
1306 != ((HOST_WIDE_INT) (-1) << (width - 1))))
1307 i0 &= ((HOST_WIDE_INT) 1 << width) - 1, i1 = 0;
1308 else if (width == HOST_BITS_PER_WIDE_INT
1309 && ! (i1 == ~0 && i0 < 0))
1311 else if (width > 2 * HOST_BITS_PER_WIDE_INT)
1312 /* We cannot represent this value as a constant. */
1315 /* If MODE fits within HOST_BITS_PER_WIDE_INT, always use a CONST_INT.
1317 ??? Strictly speaking, this is wrong if we create a CONST_INT
1318 for a large unsigned constant with the size of MODE being
1319 HOST_BITS_PER_WIDE_INT and later try to interpret that constant in a
1320 wider mode. In that case we will mis-interpret it as a negative
1323 Unfortunately, the only alternative is to make a CONST_DOUBLE
1324 for any constant in any mode if it is an unsigned constant larger
1325 than the maximum signed integer in an int on the host. However,
1326 doing this will break everyone that always expects to see a CONST_INT
1327 for SImode and smaller.
1329 We have always been making CONST_INTs in this case, so nothing new
1332 if (width <= HOST_BITS_PER_WIDE_INT)
1333 i1 = (i0 < 0) ? ~0 : 0;
1335 /* If this integer fits in one word, return a CONST_INT. */
1336 if ((i1 == 0 && i0 >= 0)
1337 || (i1 == ~0 && i0 < 0))
1338 return GEN_INT (i0);
1340 /* We use VOIDmode for integers. */
1344 /* Search the chain for an existing CONST_DOUBLE with the right value.
1345 If one is found, return it. */
1347 for (r = const_double_chain; r; r = CONST_DOUBLE_CHAIN (r))
1348 if (CONST_DOUBLE_LOW (r) == i0 && CONST_DOUBLE_HIGH (r) == i1
1349 && GET_MODE (r) == mode)
1352 /* No; make a new one and add it to the chain.
1354 We may be called by an optimizer which may be discarding any memory
1355 allocated during its processing (such as combine and loop). However,
1356 we will be leaving this constant on the chain, so we cannot tolerate
1357 freed memory. So switch to saveable_obstack for this allocation
1358 and then switch back if we were in current_obstack. */
1360 push_obstacks_nochange ();
1361 rtl_in_saveable_obstack ();
1362 r = gen_rtx (CONST_DOUBLE, mode, 0, i0, i1);
1365 /* Don't touch const_double_chain in nested function;
1366 see force_const_mem. */
1367 if (outer_function_chain == 0)
1369 CONST_DOUBLE_CHAIN (r) = const_double_chain;
1370 const_double_chain = r;
1373 /* Store const0_rtx in mem-slot since this CONST_DOUBLE is on the chain.
1374 Actual use of mem-slot is only through force_const_mem. */
1376 CONST_DOUBLE_MEM (r) = const0_rtx;
1381 /* Return a CONST_DOUBLE for a specified `double' value
1382 and machine mode. */
1385 immed_real_const_1 (d, mode)
1387 enum machine_mode mode;
1389 union real_extract u;
1391 int in_current_obstack;
1393 /* Get the desired `double' value as a sequence of ints
1394 since that is how they are stored in a CONST_DOUBLE. */
1398 /* Detect special cases. */
1400 /* Avoid REAL_VALUES_EQUAL here in order to distinguish minus zero. */
1401 if (!bcmp (&dconst0, &d, sizeof d))
1402 return CONST0_RTX (mode);
1403 else if (REAL_VALUES_EQUAL (dconst1, d))
1404 return CONST1_RTX (mode);
1406 if (sizeof u == 2 * sizeof (HOST_WIDE_INT))
1407 return immed_double_const (u.i[0], u.i[1], mode);
1409 /* The rest of this function handles the case where
1410 a float value requires more than 2 ints of space.
1411 It will be deleted as dead code on machines that don't need it. */
1413 /* Search the chain for an existing CONST_DOUBLE with the right value.
1414 If one is found, return it. */
1416 for (r = const_double_chain; r; r = CONST_DOUBLE_CHAIN (r))
1417 if (! bcmp (&CONST_DOUBLE_LOW (r), &u, sizeof u)
1418 && GET_MODE (r) == mode)
1421 /* No; make a new one and add it to the chain.
1423 We may be called by an optimizer which may be discarding any memory
1424 allocated during its processing (such as combine and loop). However,
1425 we will be leaving this constant on the chain, so we cannot tolerate
1426 freed memory. So switch to saveable_obstack for this allocation
1427 and then switch back if we were in current_obstack. */
1429 push_obstacks_nochange ();
1430 rtl_in_saveable_obstack ();
1431 r = rtx_alloc (CONST_DOUBLE);
1433 bcopy (&u, &CONST_DOUBLE_LOW (r), sizeof u);
1436 /* Don't touch const_double_chain in nested function;
1437 see force_const_mem. */
1438 if (outer_function_chain == 0)
1440 CONST_DOUBLE_CHAIN (r) = const_double_chain;
1441 const_double_chain = r;
1444 /* Store const0_rtx in CONST_DOUBLE_MEM since this CONST_DOUBLE is on the
1445 chain, but has not been allocated memory. Actual use of CONST_DOUBLE_MEM
1446 is only through force_const_mem. */
1448 CONST_DOUBLE_MEM (r) = const0_rtx;
1453 /* Return a CONST_DOUBLE rtx for a value specified by EXP,
1454 which must be a REAL_CST tree node. */
1457 immed_real_const (exp)
1460 return immed_real_const_1 (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)));
1463 /* At the end of a function, forget the memory-constants
1464 previously made for CONST_DOUBLEs. Mark them as not on real_constant_chain.
1465 Also clear out real_constant_chain and clear out all the chain-pointers. */
1468 clear_const_double_mem ()
1470 register rtx r, next;
1472 /* Don't touch CONST_DOUBLE_MEM for nested functions.
1473 See force_const_mem for explanation. */
1474 if (outer_function_chain != 0)
1477 for (r = const_double_chain; r; r = next)
1479 next = CONST_DOUBLE_CHAIN (r);
1480 CONST_DOUBLE_CHAIN (r) = 0;
1481 CONST_DOUBLE_MEM (r) = cc0_rtx;
1483 const_double_chain = 0;
1486 /* Given an expression EXP with a constant value,
1487 reduce it to the sum of an assembler symbol and an integer.
1488 Store them both in the structure *VALUE.
1489 Abort if EXP does not reduce. */
1494 HOST_WIDE_INT offset;
1498 decode_addr_const (exp, value)
1500 struct addr_const *value;
1502 register tree target = TREE_OPERAND (exp, 0);
1503 register int offset = 0;
1508 if (TREE_CODE (target) == COMPONENT_REF
1509 && (TREE_CODE (DECL_FIELD_BITPOS (TREE_OPERAND (target, 1)))
1512 offset += TREE_INT_CST_LOW (DECL_FIELD_BITPOS (TREE_OPERAND (target, 1))) / BITS_PER_UNIT;
1513 target = TREE_OPERAND (target, 0);
1515 else if (TREE_CODE (target) == ARRAY_REF)
1517 if (TREE_CODE (TREE_OPERAND (target, 1)) != INTEGER_CST
1518 || TREE_CODE (TYPE_SIZE (TREE_TYPE (target))) != INTEGER_CST)
1520 offset += ((TREE_INT_CST_LOW (TYPE_SIZE (TREE_TYPE (target)))
1521 * TREE_INT_CST_LOW (TREE_OPERAND (target, 1)))
1523 target = TREE_OPERAND (target, 0);
1529 switch (TREE_CODE (target))
1533 x = DECL_RTL (target);
1537 x = gen_rtx (MEM, FUNCTION_MODE,
1538 gen_rtx (LABEL_REF, VOIDmode,
1539 label_rtx (TREE_OPERAND (exp, 0))));
1546 x = TREE_CST_RTL (target);
1553 if (GET_CODE (x) != MEM)
1558 value->offset = offset;
1561 /* Uniquize all constants that appear in memory.
1562 Each constant in memory thus far output is recorded
1563 in `const_hash_table' with a `struct constant_descriptor'
1564 that contains a polish representation of the value of
1567 We cannot store the trees in the hash table
1568 because the trees may be temporary. */
1570 struct constant_descriptor
1572 struct constant_descriptor *next;
1578 #define MAX_HASH_TABLE 1009
1579 static struct constant_descriptor *const_hash_table[MAX_HASH_TABLE];
1581 /* Compute a hash code for a constant expression. */
1588 register int len, hi, i;
1589 register enum tree_code code = TREE_CODE (exp);
1591 if (code == INTEGER_CST)
1593 p = (char *) &TREE_INT_CST_LOW (exp);
1594 len = 2 * sizeof TREE_INT_CST_LOW (exp);
1596 else if (code == REAL_CST)
1598 p = (char *) &TREE_REAL_CST (exp);
1599 len = sizeof TREE_REAL_CST (exp);
1601 else if (code == STRING_CST)
1602 p = TREE_STRING_POINTER (exp), len = TREE_STRING_LENGTH (exp);
1603 else if (code == COMPLEX_CST)
1604 return const_hash (TREE_REALPART (exp)) * 5
1605 + const_hash (TREE_IMAGPART (exp));
1606 else if (code == CONSTRUCTOR)
1610 /* For record type, include the type in the hashing.
1611 We do not do so for array types
1612 because (1) the sizes of the elements are sufficient
1613 and (2) distinct array types can have the same constructor.
1614 Instead, we include the array size because the constructor could
1616 if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE)
1617 hi = ((HOST_WIDE_INT) TREE_TYPE (exp) & ((1 << HASHBITS) - 1))
1620 hi = ((5 + int_size_in_bytes (TREE_TYPE (exp)))
1621 & ((1 << HASHBITS) - 1)) % MAX_HASH_TABLE;
1623 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link))
1624 if (TREE_VALUE (link))
1625 hi = (hi * 603 + const_hash (TREE_VALUE (link))) % MAX_HASH_TABLE;
1629 else if (code == ADDR_EXPR)
1631 struct addr_const value;
1632 decode_addr_const (exp, &value);
1633 if (GET_CODE (value.base) == SYMBOL_REF)
1635 /* Don't hash the address of the SYMBOL_REF;
1636 only use the offset and the symbol name. */
1638 p = XSTR (value.base, 0);
1639 for (i = 0; p[i] != 0; i++)
1640 hi = ((hi * 613) + (unsigned)(p[i]));
1642 else if (GET_CODE (value.base) == LABEL_REF)
1643 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13;
1645 hi &= (1 << HASHBITS) - 1;
1646 hi %= MAX_HASH_TABLE;
1649 else if (code == PLUS_EXPR || code == MINUS_EXPR)
1650 return const_hash (TREE_OPERAND (exp, 0)) * 9
1651 + const_hash (TREE_OPERAND (exp, 1));
1652 else if (code == NOP_EXPR || code == CONVERT_EXPR)
1653 return const_hash (TREE_OPERAND (exp, 0)) * 7 + 2;
1655 /* Compute hashing function */
1657 for (i = 0; i < len; i++)
1658 hi = ((hi * 613) + (unsigned)(p[i]));
1660 hi &= (1 << HASHBITS) - 1;
1661 hi %= MAX_HASH_TABLE;
1665 /* Compare a constant expression EXP with a constant-descriptor DESC.
1666 Return 1 if DESC describes a constant with the same value as EXP. */
1669 compare_constant (exp, desc)
1671 struct constant_descriptor *desc;
1673 return 0 != compare_constant_1 (exp, desc->contents);
1676 /* Compare constant expression EXP with a substring P of a constant descriptor.
1677 If they match, return a pointer to the end of the substring matched.
1678 If they do not match, return 0.
1680 Since descriptors are written in polish prefix notation,
1681 this function can be used recursively to test one operand of EXP
1682 against a subdescriptor, and if it succeeds it returns the
1683 address of the subdescriptor for the next operand. */
1686 compare_constant_1 (exp, p)
1690 register char *strp;
1692 register enum tree_code code = TREE_CODE (exp);
1694 if (code != (enum tree_code) *p++)
1697 if (code == INTEGER_CST)
1699 /* Integer constants are the same only if the same width of type. */
1700 if (*p++ != TYPE_PRECISION (TREE_TYPE (exp)))
1702 strp = (char *) &TREE_INT_CST_LOW (exp);
1703 len = 2 * sizeof TREE_INT_CST_LOW (exp);
1705 else if (code == REAL_CST)
1707 /* Real constants are the same only if the same width of type. */
1708 if (*p++ != TYPE_PRECISION (TREE_TYPE (exp)))
1710 strp = (char *) &TREE_REAL_CST (exp);
1711 len = sizeof TREE_REAL_CST (exp);
1713 else if (code == STRING_CST)
1715 if (flag_writable_strings)
1717 strp = TREE_STRING_POINTER (exp);
1718 len = TREE_STRING_LENGTH (exp);
1719 if (bcmp (&TREE_STRING_LENGTH (exp), p,
1720 sizeof TREE_STRING_LENGTH (exp)))
1722 p += sizeof TREE_STRING_LENGTH (exp);
1724 else if (code == COMPLEX_CST)
1726 p = compare_constant_1 (TREE_REALPART (exp), p);
1727 if (p == 0) return 0;
1728 p = compare_constant_1 (TREE_IMAGPART (exp), p);
1731 else if (code == CONSTRUCTOR)
1734 int length = list_length (CONSTRUCTOR_ELTS (exp));
1737 if (bcmp (&length, p, sizeof length))
1741 /* For record constructors, insist that the types match.
1742 For arrays, just verify both constructors are for arrays. */
1743 if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE)
1744 type = TREE_TYPE (exp);
1747 if (bcmp (&type, p, sizeof type))
1751 /* For arrays, insist that the size in bytes match. */
1752 if (TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE)
1754 int size = int_size_in_bytes (TREE_TYPE (exp));
1755 if (bcmp (&size, p, sizeof size))
1760 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link))
1762 if (TREE_VALUE (link))
1764 if ((p = compare_constant_1 (TREE_VALUE (link), p)) == 0)
1771 if (bcmp (&zero, p, sizeof zero))
1779 else if (code == ADDR_EXPR)
1781 struct addr_const value;
1782 decode_addr_const (exp, &value);
1783 strp = (char *) &value.offset;
1784 len = sizeof value.offset;
1785 /* Compare the offset. */
1787 if (*p++ != *strp++)
1789 /* Compare symbol name. */
1790 strp = XSTR (value.base, 0);
1791 len = strlen (strp) + 1;
1793 else if (code == PLUS_EXPR || code == MINUS_EXPR)
1795 p = compare_constant_1 (TREE_OPERAND (exp, 0), p);
1796 if (p == 0) return 0;
1797 p = compare_constant_1 (TREE_OPERAND (exp, 1), p);
1800 else if (code == NOP_EXPR || code == CONVERT_EXPR)
1802 p = compare_constant_1 (TREE_OPERAND (exp, 0), p);
1806 /* Compare constant contents. */
1808 if (*p++ != *strp++)
1814 /* Construct a constant descriptor for the expression EXP.
1815 It is up to the caller to enter the descriptor in the hash table. */
1817 static struct constant_descriptor *
1818 record_constant (exp)
1821 struct constant_descriptor *ptr = 0;
1824 obstack_grow (&permanent_obstack, &ptr, sizeof ptr);
1825 obstack_grow (&permanent_obstack, &buf, sizeof buf);
1826 record_constant_1 (exp);
1827 return (struct constant_descriptor *) obstack_finish (&permanent_obstack);
1830 /* Add a description of constant expression EXP
1831 to the object growing in `permanent_obstack'.
1832 No need to return its address; the caller will get that
1833 from the obstack when the object is complete. */
1836 record_constant_1 (exp)
1839 register char *strp;
1841 register enum tree_code code = TREE_CODE (exp);
1843 obstack_1grow (&permanent_obstack, (unsigned int) code);
1845 if (code == INTEGER_CST)
1847 obstack_1grow (&permanent_obstack, TYPE_PRECISION (TREE_TYPE (exp)));
1848 strp = (char *) &TREE_INT_CST_LOW (exp);
1849 len = 2 * sizeof TREE_INT_CST_LOW (exp);
1851 else if (code == REAL_CST)
1853 obstack_1grow (&permanent_obstack, TYPE_PRECISION (TREE_TYPE (exp)));
1854 strp = (char *) &TREE_REAL_CST (exp);
1855 len = sizeof TREE_REAL_CST (exp);
1857 else if (code == STRING_CST)
1859 if (flag_writable_strings)
1861 strp = TREE_STRING_POINTER (exp);
1862 len = TREE_STRING_LENGTH (exp);
1863 obstack_grow (&permanent_obstack, (char *) &TREE_STRING_LENGTH (exp),
1864 sizeof TREE_STRING_LENGTH (exp));
1866 else if (code == COMPLEX_CST)
1868 record_constant_1 (TREE_REALPART (exp));
1869 record_constant_1 (TREE_IMAGPART (exp));
1872 else if (code == CONSTRUCTOR)
1875 int length = list_length (CONSTRUCTOR_ELTS (exp));
1878 obstack_grow (&permanent_obstack, (char *) &length, sizeof length);
1880 /* For record constructors, insist that the types match.
1881 For arrays, just verify both constructors are for arrays. */
1882 if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE)
1883 type = TREE_TYPE (exp);
1886 obstack_grow (&permanent_obstack, (char *) &type, sizeof type);
1888 /* For arrays, insist that the size in bytes match. */
1889 if (TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE)
1891 int size = int_size_in_bytes (TREE_TYPE (exp));
1892 obstack_grow (&permanent_obstack, (char *) &size, sizeof size);
1895 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link))
1897 if (TREE_VALUE (link))
1898 record_constant_1 (TREE_VALUE (link));
1903 obstack_grow (&permanent_obstack, (char *) &zero, sizeof zero);
1909 else if (code == ADDR_EXPR)
1911 struct addr_const value;
1912 decode_addr_const (exp, &value);
1913 /* Record the offset. */
1914 obstack_grow (&permanent_obstack,
1915 (char *) &value.offset, sizeof value.offset);
1916 /* Record the symbol name. */
1917 obstack_grow (&permanent_obstack, XSTR (value.base, 0),
1918 strlen (XSTR (value.base, 0)) + 1);
1921 else if (code == PLUS_EXPR || code == MINUS_EXPR)
1923 record_constant_1 (TREE_OPERAND (exp, 0));
1924 record_constant_1 (TREE_OPERAND (exp, 1));
1927 else if (code == NOP_EXPR || code == CONVERT_EXPR)
1929 record_constant_1 (TREE_OPERAND (exp, 0));
1933 /* Record constant contents. */
1934 obstack_grow (&permanent_obstack, strp, len);
1937 /* Return an rtx representing a reference to constant data in memory
1938 for the constant expression EXP.
1939 If assembler code for such a constant has already been output,
1940 return an rtx to refer to it.
1941 Otherwise, output such a constant in memory and generate
1942 an rtx for it. The TREE_CST_RTL of EXP is set up to point to that rtx.
1943 The const_hash_table records which constants already have label strings. */
1946 output_constant_def (exp)
1949 register int hash, align;
1950 register struct constant_descriptor *desc;
1956 if (TREE_CODE (exp) == INTEGER_CST)
1957 abort (); /* No TREE_CST_RTL slot in these. */
1959 if (TREE_CST_RTL (exp))
1960 return TREE_CST_RTL (exp);
1962 /* Make sure any other constants whose addresses appear in EXP
1963 are assigned label numbers. */
1965 reloc = output_addressed_constants (exp);
1967 /* Compute hash code of EXP. Search the descriptors for that hash code
1968 to see if any of them describes EXP. If yes, the descriptor records
1969 the label number already assigned. */
1971 hash = const_hash (exp) % MAX_HASH_TABLE;
1973 for (desc = const_hash_table[hash]; desc; desc = desc->next)
1974 if (compare_constant (exp, desc))
1976 found = desc->label;
1982 /* No constant equal to EXP is known to have been output.
1983 Make a constant descriptor to enter EXP in the hash table.
1984 Assign the label number and record it in the descriptor for
1985 future calls to this function to find. */
1987 /* Create a string containing the label name, in LABEL. */
1988 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
1990 desc = record_constant (exp);
1991 desc->next = const_hash_table[hash];
1993 = (char *) obstack_copy0 (&permanent_obstack, label, strlen (label));
1994 const_hash_table[hash] = desc;
1997 /* We have a symbol name; construct the SYMBOL_REF and the MEM. */
1999 push_obstacks_nochange ();
2000 if (TREE_PERMANENT (exp))
2001 end_temporary_allocation ();
2003 def = gen_rtx (SYMBOL_REF, Pmode, desc->label);
2006 = gen_rtx (MEM, TYPE_MODE (TREE_TYPE (exp)), def);
2007 RTX_UNCHANGING_P (TREE_CST_RTL (exp)) = 1;
2008 if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE
2009 || TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE)
2010 MEM_IN_STRUCT_P (TREE_CST_RTL (exp)) = 1;
2014 /* Optionally set flags or add text to the name to record information
2015 such as that it is a function name. If the name is changed, the macro
2016 ASM_OUTPUT_LABELREF will have to know how to strip this information.
2017 And if it finds a * at the beginning after doing so, it must handle
2019 #ifdef ENCODE_SECTION_INFO
2020 ENCODE_SECTION_INFO (exp);
2025 /* Now output assembler code to define that label
2026 and follow it with the data of EXP. */
2028 /* First switch to text section, except for writable strings. */
2029 #ifdef SELECT_SECTION
2030 SELECT_SECTION (exp, reloc);
2032 if (((TREE_CODE (exp) == STRING_CST) && flag_writable_strings)
2033 || (flag_pic && reloc))
2036 readonly_data_section ();
2039 /* Align the location counter as required by EXP's data type. */
2040 align = TYPE_ALIGN (TREE_TYPE (exp));
2041 #ifdef CONSTANT_ALIGNMENT
2042 align = CONSTANT_ALIGNMENT (exp, align);
2045 if (align > BITS_PER_UNIT)
2046 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2048 /* Output the label itself. */
2049 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LC", const_labelno);
2051 /* Output the value of EXP. */
2052 output_constant (exp,
2053 (TREE_CODE (exp) == STRING_CST
2054 ? TREE_STRING_LENGTH (exp)
2055 : int_size_in_bytes (TREE_TYPE (exp))));
2060 return TREE_CST_RTL (exp);
2063 /* Similar hash facility for making memory-constants
2064 from constant rtl-expressions. It is used on RISC machines
2065 where immediate integer arguments and constant addresses are restricted
2066 so that such constants must be stored in memory.
2068 This pool of constants is reinitialized for each function
2069 so each function gets its own constants-pool that comes right before it.
2071 All structures allocated here are discarded when functions are saved for
2072 inlining, so they do not need to be allocated permanently. */
2074 #define MAX_RTX_HASH_TABLE 61
2075 static struct constant_descriptor **const_rtx_hash_table;
2077 /* Structure to represent sufficient information about a constant so that
2078 it can be output when the constant pool is output, so that function
2079 integration can be done, and to simplify handling on machines that reference
2080 constant pool as base+displacement. */
2082 struct pool_constant
2084 struct constant_descriptor *desc;
2085 struct pool_constant *next;
2086 enum machine_mode mode;
2093 /* Pointers to first and last constant in pool. */
2095 static struct pool_constant *first_pool, *last_pool;
2097 /* Current offset in constant pool (does not include any machine-specific
2100 static int pool_offset;
2102 /* Structure used to maintain hash table mapping symbols used to their
2103 corresponding constants. */
2108 struct pool_constant *pool;
2109 struct pool_sym *next;
2112 static struct pool_sym **const_rtx_sym_hash_table;
2114 /* Hash code for a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true.
2115 The argument is XSTR (... , 0) */
2117 #define SYMHASH(LABEL) \
2118 ((((HOST_WIDE_INT) (LABEL)) & ((1 << HASHBITS) - 1)) % MAX_RTX_HASH_TABLE)
2120 /* Initialize constant pool hashing for next function. */
2123 init_const_rtx_hash_table ()
2125 const_rtx_hash_table
2126 = ((struct constant_descriptor **)
2127 oballoc (MAX_RTX_HASH_TABLE * sizeof (struct constant_descriptor *)));
2128 const_rtx_sym_hash_table
2129 = ((struct pool_sym **)
2130 oballoc (MAX_RTX_HASH_TABLE * sizeof (struct pool_sym *)));
2131 bzero (const_rtx_hash_table,
2132 MAX_RTX_HASH_TABLE * sizeof (struct constant_descriptor *));
2133 bzero (const_rtx_sym_hash_table,
2134 MAX_RTX_HASH_TABLE * sizeof (struct pool_sym *));
2136 first_pool = last_pool = 0;
2140 /* Save and restore it for a nested function. */
2143 save_varasm_status (p)
2146 p->const_rtx_hash_table = const_rtx_hash_table;
2147 p->const_rtx_sym_hash_table = const_rtx_sym_hash_table;
2148 p->first_pool = first_pool;
2149 p->last_pool = last_pool;
2150 p->pool_offset = pool_offset;
2154 restore_varasm_status (p)
2157 const_rtx_hash_table = p->const_rtx_hash_table;
2158 const_rtx_sym_hash_table = p->const_rtx_sym_hash_table;
2159 first_pool = p->first_pool;
2160 last_pool = p->last_pool;
2161 pool_offset = p->pool_offset;
2164 enum kind { RTX_DOUBLE, RTX_INT };
2168 #ifdef ONLY_INT_FIELDS
2169 unsigned int kind : 16;
2170 unsigned int mode : 16;
2172 enum kind kind : 16;
2173 enum machine_mode mode : 16;
2176 union real_extract du;
2177 struct addr_const addr;
2181 /* Express an rtx for a constant integer (perhaps symbolic)
2182 as the sum of a symbol or label plus an explicit integer.
2183 They are stored into VALUE. */
2186 decode_rtx_const (mode, x, value)
2187 enum machine_mode mode;
2189 struct rtx_const *value;
2191 /* Clear the whole structure, including any gaps. */
2194 int *p = (int *) value;
2195 int *end = (int *) (value + 1);
2200 value->kind = RTX_INT; /* Most usual kind. */
2203 switch (GET_CODE (x))
2206 value->kind = RTX_DOUBLE;
2207 value->mode = GET_MODE (x);
2208 bcopy (&CONST_DOUBLE_LOW (x), &value->un.du, sizeof value->un.du);
2212 value->un.addr.offset = INTVAL (x);
2218 value->un.addr.base = x;
2223 if (GET_CODE (x) == PLUS)
2225 value->un.addr.base = XEXP (x, 0);
2226 if (GET_CODE (XEXP (x, 1)) != CONST_INT)
2228 value->un.addr.offset = INTVAL (XEXP (x, 1));
2230 else if (GET_CODE (x) == MINUS)
2232 value->un.addr.base = XEXP (x, 0);
2233 if (GET_CODE (XEXP (x, 1)) != CONST_INT)
2235 value->un.addr.offset = - INTVAL (XEXP (x, 1));
2245 if (value->kind == RTX_INT && value->un.addr.base != 0)
2246 switch (GET_CODE (value->un.addr.base))
2250 /* Use the string's address, not the SYMBOL_REF's address,
2251 for the sake of addresses of library routines.
2252 For a LABEL_REF, compare labels. */
2253 value->un.addr.base = XEXP (value->un.addr.base, 0);
2257 /* Given a MINUS expression, simplify it if both sides
2258 include the same symbol. */
2261 simplify_subtraction (x)
2264 struct rtx_const val0, val1;
2266 decode_rtx_const (GET_MODE (x), XEXP (x, 0), &val0);
2267 decode_rtx_const (GET_MODE (x), XEXP (x, 1), &val1);
2269 if (val0.un.addr.base == val1.un.addr.base)
2270 return GEN_INT (val0.un.addr.offset - val1.un.addr.offset);
2274 /* Compute a hash code for a constant RTL expression. */
2277 const_hash_rtx (mode, x)
2278 enum machine_mode mode;
2283 struct rtx_const value;
2284 decode_rtx_const (mode, x, &value);
2286 /* Compute hashing function */
2288 for (i = 0; i < sizeof value / sizeof (int); i++)
2289 hi += ((int *) &value)[i];
2291 hi &= (1 << HASHBITS) - 1;
2292 hi %= MAX_RTX_HASH_TABLE;
2296 /* Compare a constant rtl object X with a constant-descriptor DESC.
2297 Return 1 if DESC describes a constant with the same value as X. */
2300 compare_constant_rtx (mode, x, desc)
2301 enum machine_mode mode;
2303 struct constant_descriptor *desc;
2305 register int *p = (int *) desc->contents;
2308 struct rtx_const value;
2310 decode_rtx_const (mode, x, &value);
2311 strp = (int *) &value;
2312 len = sizeof value / sizeof (int);
2314 /* Compare constant contents. */
2316 if (*p++ != *strp++)
2322 /* Construct a constant descriptor for the rtl-expression X.
2323 It is up to the caller to enter the descriptor in the hash table. */
2325 static struct constant_descriptor *
2326 record_constant_rtx (mode, x)
2327 enum machine_mode mode;
2330 struct constant_descriptor *ptr;
2332 struct rtx_const value;
2334 decode_rtx_const (mode, x, &value);
2336 obstack_grow (current_obstack, &ptr, sizeof ptr);
2337 obstack_grow (current_obstack, &label, sizeof label);
2339 /* Record constant contents. */
2340 obstack_grow (current_obstack, &value, sizeof value);
2342 return (struct constant_descriptor *) obstack_finish (current_obstack);
2345 /* Given a constant rtx X, make (or find) a memory constant for its value
2346 and return a MEM rtx to refer to it in memory. */
2349 force_const_mem (mode, x)
2350 enum machine_mode mode;
2354 register struct constant_descriptor *desc;
2359 /* If we want this CONST_DOUBLE in the same mode as it is in memory
2360 (this will always be true for floating CONST_DOUBLEs that have been
2361 placed in memory, but not for VOIDmode (integer) CONST_DOUBLEs),
2362 use the previous copy. Otherwise, make a new one. Note that in
2363 the unlikely event that this same CONST_DOUBLE is used in two different
2364 modes in an alternating fashion, we will allocate a lot of different
2365 memory locations, but this should be extremely rare. */
2367 /* Don't use CONST_DOUBLE_MEM in a nested function.
2368 Nested functions have their own constant pools,
2369 so they can't share the same values in CONST_DOUBLE_MEM
2370 with the containing function. */
2371 if (outer_function_chain == 0)
2372 if (GET_CODE (x) == CONST_DOUBLE
2373 && GET_CODE (CONST_DOUBLE_MEM (x)) == MEM
2374 && GET_MODE (CONST_DOUBLE_MEM (x)) == mode)
2375 return CONST_DOUBLE_MEM (x);
2377 /* Compute hash code of X. Search the descriptors for that hash code
2378 to see if any of them describes X. If yes, the descriptor records
2379 the label number already assigned. */
2381 hash = const_hash_rtx (mode, x);
2383 for (desc = const_rtx_hash_table[hash]; desc; desc = desc->next)
2384 if (compare_constant_rtx (mode, x, desc))
2386 found = desc->label;
2392 register struct pool_constant *pool;
2393 register struct pool_sym *sym;
2396 /* No constant equal to X is known to have been output.
2397 Make a constant descriptor to enter X in the hash table.
2398 Assign the label number and record it in the descriptor for
2399 future calls to this function to find. */
2401 desc = record_constant_rtx (mode, x);
2402 desc->next = const_rtx_hash_table[hash];
2403 const_rtx_hash_table[hash] = desc;
2405 /* Align the location counter as required by EXP's data type. */
2406 align = (mode == VOIDmode) ? UNITS_PER_WORD : GET_MODE_SIZE (mode);
2407 if (align > BIGGEST_ALIGNMENT / BITS_PER_UNIT)
2408 align = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
2410 pool_offset += align - 1;
2411 pool_offset &= ~ (align - 1);
2413 /* Allocate a pool constant descriptor, fill it in, and chain it in. */
2415 pool = (struct pool_constant *) oballoc (sizeof (struct pool_constant));
2419 pool->labelno = const_labelno;
2420 pool->align = align;
2421 pool->offset = pool_offset;
2427 last_pool->next = pool;
2430 pool_offset += GET_MODE_SIZE (mode);
2432 /* Create a string containing the label name, in LABEL. */
2433 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
2438 = (char *) obstack_copy0 (saveable_obstack, label, strlen (label));
2440 /* Add label to symbol hash table. */
2441 hash = SYMHASH (found);
2442 sym = (struct pool_sym *) oballoc (sizeof (struct pool_sym));
2445 sym->next = const_rtx_sym_hash_table[hash];
2446 const_rtx_sym_hash_table[hash] = sym;
2449 /* We have a symbol name; construct the SYMBOL_REF and the MEM. */
2451 def = gen_rtx (MEM, mode, gen_rtx (SYMBOL_REF, Pmode, found));
2453 RTX_UNCHANGING_P (def) = 1;
2454 /* Mark the symbol_ref as belonging to this constants pool. */
2455 CONSTANT_POOL_ADDRESS_P (XEXP (def, 0)) = 1;
2456 current_function_uses_const_pool = 1;
2458 if (outer_function_chain == 0)
2459 if (GET_CODE (x) == CONST_DOUBLE)
2461 if (CONST_DOUBLE_MEM (x) == cc0_rtx)
2463 CONST_DOUBLE_CHAIN (x) = const_double_chain;
2464 const_double_chain = x;
2466 CONST_DOUBLE_MEM (x) = def;
2472 /* Given a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true, return a pointer to
2473 the corresponding pool_constant structure. */
2475 static struct pool_constant *
2476 find_pool_constant (addr)
2479 struct pool_sym *sym;
2480 char *label = XSTR (addr, 0);
2482 for (sym = const_rtx_sym_hash_table[SYMHASH (label)]; sym; sym = sym->next)
2483 if (sym->label == label)
2489 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
2492 get_pool_constant (addr)
2495 return (find_pool_constant (addr))->constant;
2498 /* Similar, return the mode. */
2501 get_pool_mode (addr)
2504 return (find_pool_constant (addr))->mode;
2507 /* Similar, return the offset in the constant pool. */
2510 get_pool_offset (addr)
2513 return (find_pool_constant (addr))->offset;
2516 /* Return the size of the constant pool. */
2524 /* Write all the constants in the constant pool. */
2527 output_constant_pool (fnname, fndecl)
2531 struct pool_constant *pool;
2533 union real_extract u;
2535 #ifdef ASM_OUTPUT_POOL_PROLOGUE
2536 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool_offset);
2539 for (pool = first_pool; pool; pool = pool->next)
2543 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
2544 whose CODE_LABEL has been deleted. This can occur if a jump table
2545 is eliminated by optimization. If so, write a constant of zero
2546 instead. Note that this can also happen by turning the
2547 CODE_LABEL into a NOTE. */
2548 if (((GET_CODE (x) == LABEL_REF
2549 && (INSN_DELETED_P (XEXP (x, 0))
2550 || GET_CODE (XEXP (x, 0)) == NOTE)))
2551 || (GET_CODE (x) == CONST && GET_CODE (XEXP (x, 0)) == PLUS
2552 && GET_CODE (XEXP (XEXP (x, 0), 0)) == LABEL_REF
2553 && (INSN_DELETED_P (XEXP (XEXP (XEXP (x, 0), 0), 0))
2554 || GET_CODE (XEXP (XEXP (XEXP (x, 0), 0), 0)) == NOTE)))
2557 /* First switch to correct section. */
2558 #ifdef SELECT_RTX_SECTION
2559 SELECT_RTX_SECTION (pool->mode, x);
2561 readonly_data_section ();
2564 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
2565 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, pool->mode,
2566 pool->align, pool->labelno, done);
2569 if (pool->align > 1)
2570 ASM_OUTPUT_ALIGN (asm_out_file, exact_log2 (pool->align));
2572 /* Output the label. */
2573 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LC", pool->labelno);
2575 /* Output the value of the constant itself. */
2576 switch (GET_MODE_CLASS (pool->mode))
2579 if (GET_CODE (x) != CONST_DOUBLE)
2582 bcopy (&CONST_DOUBLE_LOW (x), &u, sizeof u);
2583 assemble_real (u.d, pool->mode);
2587 case MODE_PARTIAL_INT:
2588 assemble_integer (x, GET_MODE_SIZE (pool->mode), 1);
2598 /* Done with this pool. */
2599 first_pool = last_pool = 0;
2602 /* Find all the constants whose addresses are referenced inside of EXP,
2603 and make sure assembler code with a label has been output for each one.
2604 Indicate whether an ADDR_EXPR has been encountered. */
2607 output_addressed_constants (exp)
2612 switch (TREE_CODE (exp))
2616 register tree constant = TREE_OPERAND (exp, 0);
2618 while (TREE_CODE (constant) == COMPONENT_REF)
2620 constant = TREE_OPERAND (constant, 0);
2623 if (TREE_CODE_CLASS (TREE_CODE (constant)) == 'c'
2624 || TREE_CODE (constant) == CONSTRUCTOR)
2625 /* No need to do anything here
2626 for addresses of variables or functions. */
2627 output_constant_def (constant);
2634 reloc = output_addressed_constants (TREE_OPERAND (exp, 0));
2635 reloc |= output_addressed_constants (TREE_OPERAND (exp, 1));
2640 case NON_LVALUE_EXPR:
2641 reloc = output_addressed_constants (TREE_OPERAND (exp, 0));
2647 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link))
2648 if (TREE_VALUE (link) != 0)
2649 reloc |= output_addressed_constants (TREE_VALUE (link));
2659 /* Output assembler code for constant EXP to FILE, with no label.
2660 This includes the pseudo-op such as ".int" or ".byte", and a newline.
2661 Assumes output_addressed_constants has been done on EXP already.
2663 Generate exactly SIZE bytes of assembler data, padding at the end
2664 with zeros if necessary. SIZE must always be specified.
2666 SIZE is important for structure constructors,
2667 since trailing members may have been omitted from the constructor.
2668 It is also important for initialization of arrays from string constants
2669 since the full length of the string constant might not be wanted.
2670 It is also needed for initialization of unions, where the initializer's
2671 type is just one member, and that may not be as long as the union.
2673 There a case in which we would fail to output exactly SIZE bytes:
2674 for a structure constructor that wants to produce more than SIZE bytes.
2675 But such constructors will never be generated for any possible input. */
2678 output_constant (exp, size)
2682 register enum tree_code code = TREE_CODE (TREE_TYPE (exp));
2688 /* Allow a constructor with no elements for any data type.
2689 This means to fill the space with zeros. */
2690 if (TREE_CODE (exp) == CONSTRUCTOR && CONSTRUCTOR_ELTS (exp) == 0)
2692 assemble_zeros (size);
2696 /* Eliminate the NOP_EXPR that makes a cast not be an lvalue.
2697 That way we get the constant (we hope) inside it. */
2698 if (TREE_CODE (exp) == NOP_EXPR
2699 && TREE_TYPE (exp) == TREE_TYPE (TREE_OPERAND (exp, 0)))
2700 exp = TREE_OPERAND (exp, 0);
2709 case REFERENCE_TYPE:
2710 /* ??? What about (int)((float)(int)&foo + 4) */
2711 while (TREE_CODE (exp) == NOP_EXPR || TREE_CODE (exp) == CONVERT_EXPR
2712 || TREE_CODE (exp) == NON_LVALUE_EXPR)
2713 exp = TREE_OPERAND (exp, 0);
2715 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
2716 EXPAND_INITIALIZER),
2718 error ("initializer for integer value is too complicated");
2723 if (TREE_CODE (exp) != REAL_CST)
2724 error ("initializer for floating value is not a floating constant");
2726 assemble_real (TREE_REAL_CST (exp),
2727 mode_for_size (size * BITS_PER_UNIT, MODE_FLOAT, 0));
2732 output_constant (TREE_REALPART (exp), size / 2);
2733 output_constant (TREE_IMAGPART (exp), size / 2);
2734 size -= (size / 2) * 2;
2738 if (TREE_CODE (exp) == CONSTRUCTOR)
2740 output_constructor (exp, size);
2743 else if (TREE_CODE (exp) == STRING_CST)
2747 if (size > TREE_STRING_LENGTH (exp))
2749 excess = size - TREE_STRING_LENGTH (exp);
2750 size = TREE_STRING_LENGTH (exp);
2753 assemble_string (TREE_STRING_POINTER (exp), size);
2762 if (TREE_CODE (exp) == CONSTRUCTOR)
2763 output_constructor (exp, size);
2770 assemble_zeros (size);
2773 /* Subroutine of output_constant, used for CONSTRUCTORs
2774 (aggregate constants).
2775 Generate at least SIZE bytes, padding if necessary. */
2778 output_constructor (exp, size)
2782 register tree link, field = 0;
2783 /* Number of bytes output or skipped so far.
2784 In other words, current position within the constructor. */
2785 int total_bytes = 0;
2786 /* Non-zero means BYTE contains part of a byte, to be output. */
2787 int byte_buffer_in_use = 0;
2790 if (HOST_BITS_PER_WIDE_INT < BITS_PER_UNIT)
2793 if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE)
2794 field = TYPE_FIELDS (TREE_TYPE (exp));
2796 /* As LINK goes through the elements of the constant,
2797 FIELD goes through the structure fields, if the constant is a structure.
2798 if the constant is a union, then we override this,
2799 by getting the field from the TREE_LIST element.
2800 But the constant could also be an array. Then FIELD is zero. */
2801 for (link = CONSTRUCTOR_ELTS (exp);
2803 link = TREE_CHAIN (link),
2804 field = field ? TREE_CHAIN (field) : 0)
2806 tree val = TREE_VALUE (link);
2807 /* the element in a union constructor specifies the proper field. */
2808 if (TREE_PURPOSE (link) != 0)
2809 field = TREE_PURPOSE (link);
2811 /* Eliminate the marker that makes a cast not be an lvalue. */
2815 if (field == 0 || !DECL_BIT_FIELD (field))
2817 register int fieldsize;
2818 /* Since this structure is static,
2819 we know the positions are constant. */
2820 int bitpos = (field ? (TREE_INT_CST_LOW (DECL_FIELD_BITPOS (field))
2824 /* An element that is not a bit-field.
2825 Output any buffered-up bit-fields preceding it. */
2826 if (byte_buffer_in_use)
2828 ASM_OUTPUT_BYTE (asm_out_file, byte);
2830 byte_buffer_in_use = 0;
2833 /* Advance to offset of this element.
2834 Note no alignment needed in an array, since that is guaranteed
2835 if each element has the proper size. */
2836 if (field != 0 && bitpos != total_bytes)
2838 assemble_zeros (bitpos - total_bytes);
2839 total_bytes = bitpos;
2842 /* Determine size this element should occupy. */
2845 if (TREE_CODE (DECL_SIZE (field)) != INTEGER_CST)
2847 if (TREE_INT_CST_LOW (DECL_SIZE (field)) > 100000)
2849 /* This avoids overflow trouble. */
2850 tree size_tree = size_binop (CEIL_DIV_EXPR,
2852 size_int (BITS_PER_UNIT));
2853 fieldsize = TREE_INT_CST_LOW (size_tree);
2857 fieldsize = TREE_INT_CST_LOW (DECL_SIZE (field));
2858 fieldsize = (fieldsize + BITS_PER_UNIT - 1) / BITS_PER_UNIT;
2862 fieldsize = int_size_in_bytes (TREE_TYPE (TREE_TYPE (exp)));
2864 /* Output the element's initial value. */
2866 assemble_zeros (fieldsize);
2868 output_constant (val, fieldsize);
2870 /* Count its size. */
2871 total_bytes += fieldsize;
2873 else if (val != 0 && TREE_CODE (val) != INTEGER_CST)
2874 error ("invalid initial value for member `%s'",
2875 IDENTIFIER_POINTER (DECL_NAME (field)));
2878 /* Element that is a bit-field. */
2880 int next_offset = TREE_INT_CST_LOW (DECL_FIELD_BITPOS (field));
2882 = (next_offset + TREE_INT_CST_LOW (DECL_SIZE (field)));
2885 val = integer_zero_node;
2887 /* If this field does not start in this (or, next) byte,
2889 if (next_offset / BITS_PER_UNIT != total_bytes)
2891 /* Output remnant of any bit field in previous bytes. */
2892 if (byte_buffer_in_use)
2894 ASM_OUTPUT_BYTE (asm_out_file, byte);
2896 byte_buffer_in_use = 0;
2899 /* If still not at proper byte, advance to there. */
2900 if (next_offset / BITS_PER_UNIT != total_bytes)
2902 assemble_zeros (next_offset / BITS_PER_UNIT - total_bytes);
2903 total_bytes = next_offset / BITS_PER_UNIT;
2907 if (! byte_buffer_in_use)
2910 /* We must split the element into pieces that fall within
2911 separate bytes, and combine each byte with previous or
2912 following bit-fields. */
2914 /* next_offset is the offset n fbits from the beginning of
2915 the structure to the next bit of this element to be processed.
2916 end_offset is the offset of the first bit past the end of
2918 while (next_offset < end_offset)
2922 int next_byte = next_offset / BITS_PER_UNIT;
2923 int next_bit = next_offset % BITS_PER_UNIT;
2925 /* Advance from byte to byte
2926 within this element when necessary. */
2927 while (next_byte != total_bytes)
2929 ASM_OUTPUT_BYTE (asm_out_file, byte);
2934 /* Number of bits we can process at once
2935 (all part of the same byte). */
2936 this_time = MIN (end_offset - next_offset,
2937 BITS_PER_UNIT - next_bit);
2938 #if BYTES_BIG_ENDIAN
2939 /* On big-endian machine, take the most significant bits
2940 first (of the bits that are significant)
2941 and put them into bytes from the most significant end. */
2942 shift = end_offset - next_offset - this_time;
2943 /* Don't try to take a bunch of bits that cross
2944 the word boundary in the INTEGER_CST. */
2945 if (shift < HOST_BITS_PER_WIDE_INT
2946 && shift + this_time > HOST_BITS_PER_WIDE_INT)
2948 this_time -= (HOST_BITS_PER_WIDE_INT - shift);
2949 shift = HOST_BITS_PER_WIDE_INT;
2952 /* Now get the bits from the appropriate constant word. */
2953 if (shift < HOST_BITS_PER_WIDE_INT)
2955 value = TREE_INT_CST_LOW (val);
2957 else if (shift < 2 * HOST_BITS_PER_WIDE_INT)
2959 value = TREE_INT_CST_HIGH (val);
2960 shift -= HOST_BITS_PER_WIDE_INT;
2964 byte |= (((value >> shift)
2965 & (((HOST_WIDE_INT) 1 << this_time) - 1))
2966 << (BITS_PER_UNIT - this_time - next_bit));
2968 /* On little-endian machines,
2969 take first the least significant bits of the value
2970 and pack them starting at the least significant
2971 bits of the bytes. */
2972 shift = (next_offset
2973 - TREE_INT_CST_LOW (DECL_FIELD_BITPOS (field)));
2974 /* Don't try to take a bunch of bits that cross
2975 the word boundary in the INTEGER_CST. */
2976 if (shift < HOST_BITS_PER_WIDE_INT
2977 && shift + this_time > HOST_BITS_PER_WIDE_INT)
2979 this_time -= (HOST_BITS_PER_WIDE_INT - shift);
2980 shift = HOST_BITS_PER_WIDE_INT;
2983 /* Now get the bits from the appropriate constant word. */
2984 if (shift < HOST_BITS_PER_INT)
2985 value = TREE_INT_CST_LOW (val);
2986 else if (shift < 2 * HOST_BITS_PER_WIDE_INT)
2988 value = TREE_INT_CST_HIGH (val);
2989 shift -= HOST_BITS_PER_WIDE_INT;
2993 byte |= ((value >> shift)
2994 & (((HOST_WIDE_INT) 1 << this_time) - 1)) << next_bit;
2996 next_offset += this_time;
2997 byte_buffer_in_use = 1;
3001 if (byte_buffer_in_use)
3003 ASM_OUTPUT_BYTE (asm_out_file, byte);
3006 if (total_bytes < size)
3007 assemble_zeros (size - total_bytes);