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> */
36 #include "hard-reg-set.h"
41 #ifdef XCOFF_DEBUGGING_INFO
46 #define ASM_STABS_OP ".stabs"
49 /* File in which assembler code is being written. */
51 extern FILE *asm_out_file
;
53 /* The (assembler) name of the first globally-visible object output. */
54 char *first_global_object_name
;
56 extern struct obstack
*current_obstack
;
57 extern struct obstack
*saveable_obstack
;
58 extern struct obstack permanent_obstack
;
59 #define obstack_chunk_alloc xmalloc
60 extern int xmalloc ();
62 /* Number for making the label on the next
63 constant that is stored in memory. */
67 /* Number for making the label on the next
68 static variable internal to a function. */
72 /* Nonzero if at least one function definition has been seen. */
73 static int function_defined
;
75 extern FILE *asm_out_file
;
77 static char *compare_constant_1 ();
78 static void record_constant_1 ();
79 void output_constant_pool ();
80 void assemble_name ();
81 int output_addressed_constants ();
82 void output_constant ();
83 void output_constructor ();
87 static enum in_section
{no_section
, in_text
, in_data
, EXTRA_SECTIONS
} in_section
90 static enum in_section
{no_section
, in_text
, in_data
} in_section
94 /* Define functions like text_section for any extra sections. */
95 #ifdef EXTRA_SECTION_FUNCTIONS
96 EXTRA_SECTION_FUNCTIONS
99 /* Tell assembler to switch to text section. */
104 if (in_section
!= in_text
)
106 fprintf (asm_out_file
, "%s\n", TEXT_SECTION_ASM_OP
);
107 in_section
= in_text
;
111 /* Tell assembler to switch to read-only data section. This is normally
115 readonly_data_section ()
117 #ifdef READONLY_DATA_SECTION
118 READONLY_DATA_SECTION ();
124 /* Tell assembler to switch to data section. */
129 if (in_section
!= in_data
)
131 if (flag_shared_data
)
133 #ifdef SHARED_SECTION_ASM_OP
134 fprintf (asm_out_file
, "%s\n", SHARED_SECTION_ASM_OP
);
136 fprintf (asm_out_file
, "%s\n", DATA_SECTION_ASM_OP
);
140 fprintf (asm_out_file
, "%s\n", DATA_SECTION_ASM_OP
);
142 in_section
= in_data
;
146 /* Determine if we're in the text section. */
151 return in_section
== in_text
;
154 /* Create the rtl to represent a function, for a function definition.
155 DECL is a FUNCTION_DECL node which describes which function.
156 The rtl is stored into DECL. */
159 make_function_rtl (decl
)
162 char *name
= IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl
));
164 /* Rename a nested function to avoid conflicts. */
165 if (decl_function_context (decl
) != 0
166 && DECL_INITIAL (decl
) != 0
167 && DECL_RTL (decl
) == 0)
171 name
= IDENTIFIER_POINTER (DECL_NAME (decl
));
172 ASM_FORMAT_PRIVATE_NAME (label
, name
, var_labelno
);
173 name
= obstack_copy0 (saveable_obstack
, label
, strlen (label
));
177 if (DECL_RTL (decl
) == 0)
180 = gen_rtx (MEM
, DECL_MODE (decl
),
181 gen_rtx (SYMBOL_REF
, Pmode
, name
));
183 /* Optionally set flags or add text to the name to record information
184 such as that it is a function name. If the name is changed, the macro
185 ASM_OUTPUT_LABELREF will have to know how to strip this information.
186 And if it finds a * at the beginning after doing so, it must handle
188 #ifdef ENCODE_SECTION_INFO
189 ENCODE_SECTION_INFO (decl
);
193 /* Record at least one function has been defined. */
194 function_defined
= 1;
197 /* Given NAME, a putative register name, discard any customary prefixes. */
200 strip_reg_name (name
)
203 #ifdef REGISTER_PREFIX
204 if (!strncmp (name
, REGISTER_PREFIX
, strlen (REGISTER_PREFIX
)))
205 name
+= strlen (REGISTER_PREFIX
);
207 if (name
[0] == '%' || name
[0] == '#')
212 /* Decode an `asm' spec for a declaration as a register name.
213 Return the register number, or -1 if nothing specified,
214 or -2 if the name is not a register. Accept an exact spelling or
215 a decimal number. Prefixes such as % are optional. */
218 decode_reg_name (asmspec
)
225 /* Get rid of confusing prefixes. */
226 asmspec
= strip_reg_name (asmspec
);
228 /* Allow a decimal number as a "register name". */
229 for (i
= strlen (asmspec
) - 1; i
>= 0; i
--)
230 if (! (asmspec
[i
] >= '0' && asmspec
[i
] <= '9'))
232 if (asmspec
[0] != 0 && i
< 0)
235 if (i
< FIRST_PSEUDO_REGISTER
&& i
>= 0)
241 for (i
= 0; i
< FIRST_PSEUDO_REGISTER
; i
++)
243 && ! strcmp (asmspec
, strip_reg_name (reg_names
[i
])))
246 #ifdef ADDITIONAL_REGISTER_NAMES
248 static struct { char *name
; int number
; } table
[]
249 = ADDITIONAL_REGISTER_NAMES
;
251 for (i
= 0; i
< sizeof (table
) / sizeof (table
[0]); i
++)
252 if (! strcmp (asmspec
, table
[i
].name
))
253 return table
[i
].number
;
255 #endif /* ADDITIONAL_REGISTER_NAMES */
263 /* Create the DECL_RTL for a declaration for a static or external variable
264 or static or external function.
265 ASMSPEC, if not 0, is the string which the user specified
266 as the assembler symbol name.
267 TOP_LEVEL is nonzero if this is a file-scope variable.
269 This is never called for PARM_DECL nodes. */
272 make_decl_rtl (decl
, asmspec
, top_level
)
278 int reg_number
= decode_reg_name (asmspec
);
280 if (DECL_ASSEMBLER_NAME (decl
) != NULL_TREE
)
281 name
= IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl
));
283 if (reg_number
== -2)
285 /* ASMSPEC is given, and not the name of a register. */
286 name
= (char *) obstack_alloc (saveable_obstack
,
287 strlen (asmspec
) + 2);
289 strcpy (&name
[1], asmspec
);
292 /* For a duplicate declaration, we can be called twice on the
293 same DECL node. Don't alter the RTL already made
294 unless the old mode is wrong (which can happen when
295 the previous rtl was made when the type was incomplete). */
296 if (DECL_RTL (decl
) == 0
297 || GET_MODE (DECL_RTL (decl
)) != DECL_MODE (decl
))
301 /* First detect errors in declaring global registers. */
302 if (TREE_REGDECL (decl
) && reg_number
== -1)
303 error_with_decl (decl
,
304 "register name not specified for `%s'");
305 else if (TREE_REGDECL (decl
) && reg_number
== -2)
306 error_with_decl (decl
,
307 "invalid register name for `%s'");
308 else if (reg_number
>= 0 && ! TREE_REGDECL (decl
))
309 error_with_decl (decl
,
310 "register name given for non-register variable `%s'");
311 else if (TREE_REGDECL (decl
) && TREE_CODE (decl
) == FUNCTION_DECL
)
312 error ("function declared `register'");
313 else if (TREE_REGDECL (decl
) && TYPE_MODE (TREE_TYPE (decl
)) == BLKmode
)
314 error_with_decl (decl
, "data type of `%s' isn't suitable for a register");
315 /* Now handle properly declared static register variables. */
316 else if (TREE_REGDECL (decl
))
319 #if 0 /* yylex should print the warning for this */
321 pedwarn ("ANSI C forbids global register variables");
323 if (DECL_INITIAL (decl
) != 0 && top_level
)
325 DECL_INITIAL (decl
) = 0;
326 error ("global register variable has initial value");
328 if (fixed_regs
[reg_number
] == 0
329 && function_defined
&& top_level
)
330 error ("global register variable follows a function definition");
331 if (TREE_THIS_VOLATILE (decl
))
332 warning ("volatile register variables don't work as you might wish");
333 DECL_RTL (decl
) = gen_rtx (REG
, DECL_MODE (decl
), reg_number
);
334 REG_USERVAR_P (DECL_RTL (decl
)) = 1;
338 /* Make this register fixed, so not usable for anything else. */
339 nregs
= HARD_REGNO_NREGS (reg_number
, DECL_MODE (decl
));
341 global_regs
[reg_number
+ --nregs
] = 1;
346 /* Now handle ordinary static variables and functions (in memory).
347 Also handle vars declared register invalidly. */
348 if (DECL_RTL (decl
) == 0)
350 /* Can't use just the variable's own name for a variable
351 whose scope is less than the whole file.
352 Concatenate a distinguishing number. */
353 if (!top_level
&& !TREE_EXTERNAL (decl
) && asmspec
== 0)
357 ASM_FORMAT_PRIVATE_NAME (label
, name
, var_labelno
);
358 name
= obstack_copy0 (saveable_obstack
, label
, strlen (label
));
362 DECL_RTL (decl
) = gen_rtx (MEM
, DECL_MODE (decl
),
363 gen_rtx (SYMBOL_REF
, Pmode
, name
));
364 if (TREE_THIS_VOLATILE (decl
))
365 MEM_VOLATILE_P (DECL_RTL (decl
)) = 1;
366 if (TREE_READONLY (decl
))
367 RTX_UNCHANGING_P (DECL_RTL (decl
)) = 1;
368 MEM_IN_STRUCT_P (DECL_RTL (decl
))
369 = (TREE_CODE (TREE_TYPE (decl
)) == ARRAY_TYPE
370 || TREE_CODE (TREE_TYPE (decl
)) == RECORD_TYPE
371 || TREE_CODE (TREE_TYPE (decl
)) == UNION_TYPE
);
373 /* Optionally set flags or add text to the name to record information
374 such as that it is a function name.
375 If the name is changed, the macro ASM_OUTPUT_LABELREF
376 will have to know how to strip this information.
377 And if it finds a * at the beginning after doing so,
378 it must handle that too. */
379 #ifdef ENCODE_SECTION_INFO
380 ENCODE_SECTION_INFO (decl
);
386 /* Output a string of literal assembler code
387 for an `asm' keyword used between functions. */
390 assemble_asm (string
)
395 if (TREE_CODE (string
) == ADDR_EXPR
)
396 string
= TREE_OPERAND (string
, 0);
398 fprintf (asm_out_file
, "\t%s\n", TREE_STRING_POINTER (string
));
401 /* Tiemann: please get rid of this conditional and put appropriate
402 definitions in each of the files that should have them.
403 The type of debugging format is not the right parameter to
404 control how some other aspect of assembler output is done. */
406 #if !(defined(DBX_DEBUGGING_INFO) && !defined(FASCIST_ASSEMBLER))
407 #ifndef ASM_OUTPUT_CONSTRUCTOR
408 #define ASM_OUTPUT_CONSTRUCTOR(file, name)
410 #ifndef ASM_OUTPUT_DESTRUCTOR
411 #define ASM_OUTPUT_DESTRUCTOR(file, name)
415 /* Record an element in the table of global destructors.
416 How this is done depends on what sort of assembler and linker
419 NAME should be the name of a global function to be called
420 at exit time. This name is output using assemble_name. */
423 assemble_destructor (name
)
426 #ifdef ASM_OUTPUT_DESTRUCTOR
427 ASM_OUTPUT_DESTRUCTOR (asm_out_file
, name
);
431 /* Now tell GNU LD that this is part of the static destructor set. */
432 /* This code works for any machine provided you use GNU as/ld. */
433 fprintf (asm_out_file
, "%s \"___DTOR_LIST__\",22,0,0,", ASM_STABS_OP
);
434 assemble_name (asm_out_file
, name
);
435 fputc ('\n', asm_out_file
);
440 /* Likewise for global constructors. */
443 assemble_constructor (name
)
446 #ifdef ASM_OUTPUT_CONSTRUCTOR
447 ASM_OUTPUT_CONSTRUCTOR (asm_out_file
, name
);
451 /* Now tell GNU LD that this is part of the static constructor set. */
452 /* This code works for any machine provided you use GNU as/ld. */
453 fprintf (asm_out_file
, "%s \"___CTOR_LIST__\",22,0,0,", ASM_STABS_OP
);
454 assemble_name (asm_out_file
, name
);
455 fputc ('\n', asm_out_file
);
460 /* Likewise for entries we want to record for garbage collection.
461 Garbage collection is still under development. */
464 assemble_gc_entry (name
)
467 #ifdef ASM_OUTPUT_GC_ENTRY
468 ASM_OUTPUT_GC_ENTRY (asm_out_file
, name
);
472 /* Now tell GNU LD that this is part of the static constructor set. */
473 fprintf (asm_out_file
, "%s \"___PTR_LIST__\",22,0,0,", ASM_STABS_OP
);
474 assemble_name (asm_out_file
, name
);
475 fputc ('\n', asm_out_file
);
480 /* Output assembler code for the constant pool of a function and associated
481 with defining the name of the function. DECL describes the function.
482 NAME is the function's name. For the constant pool, we use the current
483 constant pool data. */
486 assemble_start_function (decl
, fnname
)
492 /* The following code does not need preprocessing in the assembler. */
496 output_constant_pool (fnname
, decl
);
501 /* Tell assembler to move to target machine's alignment for functions. */
502 align
= floor_log2 (FUNCTION_BOUNDARY
/ BITS_PER_UNIT
);
504 ASM_OUTPUT_ALIGN (asm_out_file
, align
);
506 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
507 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file
, fnname
);
510 #ifdef SDB_DEBUGGING_INFO
511 /* Output SDB definition of the function. */
512 if (write_symbols
== SDB_DEBUG
)
513 sdbout_mark_begin_function ();
516 #ifdef DBX_DEBUGGING_INFO
517 /* Output DBX definition of the function. */
518 if (write_symbols
== DBX_DEBUG
)
519 dbxout_begin_function (decl
);
522 /* Make function name accessible from other files, if appropriate. */
524 if (TREE_PUBLIC (decl
))
526 if (!first_global_object_name
)
527 first_global_object_name
= fnname
+ (fnname
[0] == '*');
528 ASM_GLOBALIZE_LABEL (asm_out_file
, fnname
);
531 /* Do any machine/system dependent processing of the function name */
532 #ifdef ASM_DECLARE_FUNCTION_NAME
533 ASM_DECLARE_FUNCTION_NAME (asm_out_file
, fnname
, current_function_decl
);
535 /* Standard thing is just output label for the function. */
536 ASM_OUTPUT_LABEL (asm_out_file
, fnname
);
537 #endif /* ASM_DECLARE_FUNCTION_NAME */
540 /* Output assembler code associated with defining the size of the
541 function. DECL describes the function. NAME is the function's name. */
544 assemble_end_function (decl
, fnname
)
548 #ifdef ASM_DECLARE_FUNCTION_SIZE
549 ASM_DECLARE_FUNCTION_SIZE (asm_out_file
, fnname
, decl
);
553 /* Assemble code to leave SIZE bytes of zeros. */
556 assemble_zeros (size
)
559 #ifdef ASM_NO_SKIP_IN_TEXT
560 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
561 so we must output 0s explicitly in the text section. */
562 if (ASM_NO_SKIP_IN_TEXT
&& in_text_section ())
566 for (i
= 0; i
< size
- 20; i
+= 20)
569 fprintf (asm_out_file
,
570 "%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
);
572 fprintf (asm_out_file
,
573 "\tbyte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0\n");
579 fprintf (asm_out_file
, "%s 0", ASM_BYTE_OP
);
581 fprintf (asm_out_file
, "\tbyte 0");
584 for (; i
< size
; i
++)
585 fprintf (asm_out_file
, ",0");
586 fprintf (asm_out_file
, "\n");
591 ASM_OUTPUT_SKIP (asm_out_file
, size
);
594 /* Assemble a string constant with the specified C string as contents. */
597 assemble_string (p
, size
)
605 /* If the string is very long, split it up. */
609 int thissize
= size
- pos
;
610 if (thissize
> maximum
)
613 #ifdef ASM_OUTPUT_ASCII
614 ASM_OUTPUT_ASCII (asm_out_file
, p
, thissize
);
616 fprintf (asm_out_file
, "\t.ascii \"");
618 for (i
= 0; i
< thissize
; i
++)
620 register int c
= p
[i
];
621 if (c
== '\"' || c
== '\\')
622 putc ('\\', asm_out_file
);
623 if (c
>= ' ' && c
< 0177)
624 putc (c
, asm_out_file
);
627 fprintf (asm_out_file
, "\\%o", c
);
628 /* After an octal-escape, if a digit follows,
629 terminate one string constant and start another.
630 The Vax assembler fails to stop reading the escape
631 after three digits, so this is the only way we
632 can get it to parse the data properly. */
634 && p
[i
+ 1] >= '0' && p
[i
+ 1] <= '9')
635 fprintf (asm_out_file
, "\"\n\t.ascii \"");
638 fprintf (asm_out_file
, "\"\n");
639 #endif /* no ASM_OUTPUT_ASCII */
646 /* Assemble everything that is needed for a variable or function declaration.
647 Not used for automatic variables, and not used for function definitions.
648 Should not be called for variables of incomplete structure type.
650 TOP_LEVEL is nonzero if this variable has file scope.
651 AT_END is nonzero if this is the special handling, at end of compilation,
652 to define things that have had only tentative definitions. */
655 assemble_variable (decl
, top_level
, at_end
)
665 if (GET_CODE (DECL_RTL (decl
)) == REG
)
667 /* Do output symbol info for global register variables, but do nothing
670 if (TREE_ASM_WRITTEN (decl
))
672 TREE_ASM_WRITTEN (decl
) = 1;
674 #if defined (DBX_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
675 /* File-scope global variables are output here. */
676 if ((write_symbols
== DBX_DEBUG
|| write_symbols
== XCOFF_DEBUG
)
678 dbxout_symbol (decl
, 0);
680 #ifdef SDB_DEBUGGING_INFO
681 if (write_symbols
== SDB_DEBUG
&& top_level
682 /* Leave initialized global vars for end of compilation;
683 see comment in compile_file. */
684 && (TREE_PUBLIC (decl
) == 0 || DECL_INITIAL (decl
) == 0))
685 sdbout_symbol (decl
, 0);
688 /* Don't output any DWARF debugging information for variables here.
689 In the case of local variables, the information for them is output
690 when we do our recursive traversal of the tree representation for
691 the entire containing function. In the case of file-scope variables,
692 we output information for all of them at the very end of compilation
693 while we are doing our final traversal of the chain of file-scope
699 /* Normally no need to say anything for external references,
700 since assembler considers all undefined symbols external. */
702 if (TREE_EXTERNAL (decl
))
705 /* Output no assembler code for a function declaration.
706 Only definitions of functions output anything. */
708 if (TREE_CODE (decl
) == FUNCTION_DECL
)
711 /* If type was incomplete when the variable was declared,
712 see if it is complete now. */
714 if (DECL_SIZE (decl
) == 0)
715 layout_decl (decl
, 0);
717 /* Still incomplete => don't allocate it; treat the tentative defn
718 (which is what it must have been) as an `extern' reference. */
720 if (DECL_SIZE (decl
) == 0)
722 error_with_file_and_line (DECL_SOURCE_FILE (decl
),
723 DECL_SOURCE_LINE (decl
),
724 "storage size of static var `%s' isn't known",
725 IDENTIFIER_POINTER (DECL_NAME (decl
)));
729 /* The first declaration of a variable that comes through this function
730 decides whether it is global (in C, has external linkage)
731 or local (in C, has internal linkage). So do nothing more
732 if this function has already run. */
734 if (TREE_ASM_WRITTEN (decl
))
737 TREE_ASM_WRITTEN (decl
) = 1;
739 #ifdef DBX_DEBUGGING_INFO
740 /* File-scope global variables are output here. */
741 if (write_symbols
== DBX_DEBUG
&& top_level
)
742 dbxout_symbol (decl
, 0);
744 #ifdef SDB_DEBUGGING_INFO
745 if (write_symbols
== SDB_DEBUG
&& top_level
746 /* Leave initialized global vars for end of compilation;
747 see comment in compile_file. */
748 && (TREE_PUBLIC (decl
) == 0 || DECL_INITIAL (decl
) == 0))
749 sdbout_symbol (decl
, 0);
752 /* Don't output any DWARF debugging information for variables here.
753 In the case of local variables, the information for them is output
754 when we do our recursive traversal of the tree representation for
755 the entire containing function. In the case of file-scope variables,
756 we output information for all of them at the very end of compilation
757 while we are doing our final traversal of the chain of file-scope
760 /* If storage size is erroneously variable, just continue.
761 Error message was already made. */
763 if (TREE_CODE (DECL_SIZE (decl
)) != INTEGER_CST
)
768 /* This is better than explicit arithmetic, since it avoids overflow. */
769 size_tree
= size_binop (CEIL_DIV_EXPR
,
770 DECL_SIZE (decl
), size_int (BITS_PER_UNIT
));
772 if (TREE_INT_CST_HIGH (size_tree
) != 0)
774 error_with_decl (decl
, "size of variable `%s' is too large");
778 name
= XSTR (XEXP (DECL_RTL (decl
), 0), 0);
780 /* Handle uninitialized definitions. */
782 /* ANSI specifies that a tentative definition which is not merged with
783 a non-tentative definition behaves exactly like a definition with an
784 initializer equal to zero. (Section 3.7.2)
785 -fno-common gives strict ANSI behavior. Usually you don't want it. */
787 && (DECL_INITIAL (decl
) == 0 || DECL_INITIAL (decl
) == error_mark_node
))
789 int size
= TREE_INT_CST_LOW (size_tree
);
792 if (TREE_INT_CST_HIGH (size_tree
) != 0)
793 error_with_decl (decl
, "size of variable `%s' is too large");
794 /* Don't allocate zero bytes of common,
795 since that means "undefined external" in the linker. */
796 if (size
== 0) rounded
= 1;
797 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
798 so that each uninitialized object starts on such a boundary. */
799 rounded
+= (BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
) - 1;
800 rounded
= (rounded
/ (BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
)
801 * (BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
));
803 if (flag_shared_data
)
806 if (TREE_PUBLIC (decl
))
808 #ifdef ASM_OUTPUT_SHARED_COMMON
809 if (flag_shared_data
)
810 ASM_OUTPUT_SHARED_COMMON (asm_out_file
, name
, size
, rounded
);
813 #ifdef ASM_OUTPUT_ALIGNED_COMMON
814 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file
, name
, size
,
817 ASM_OUTPUT_COMMON (asm_out_file
, name
, size
, rounded
);
822 #ifdef ASM_OUTPUT_SHARED_LOCAL
823 if (flag_shared_data
)
824 ASM_OUTPUT_SHARED_LOCAL (asm_out_file
, name
, size
, rounded
);
827 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
828 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file
, name
, size
,
831 ASM_OUTPUT_LOCAL (asm_out_file
, name
, size
, rounded
);
837 /* Handle initialized definitions. */
839 /* First make the assembler name(s) global if appropriate. */
840 if (TREE_PUBLIC (decl
) && DECL_NAME (decl
))
842 if (!first_global_object_name
)
843 first_global_object_name
= name
+ (name
[0] == '*');
844 ASM_GLOBALIZE_LABEL (asm_out_file
, name
);
847 for (d
= equivalents
; d
; d
= TREE_CHAIN (d
))
849 tree e
= TREE_VALUE (d
);
850 if (TREE_PUBLIC (e
) && DECL_NAME (e
))
851 ASM_GLOBALIZE_LABEL (asm_out_file
,
852 XSTR (XEXP (DECL_RTL (e
), 0), 0));
856 /* Output any data that we will need to use the address of. */
857 if (DECL_INITIAL (decl
))
858 reloc
= output_addressed_constants (DECL_INITIAL (decl
));
860 /* Switch to the proper section for this data. */
861 #ifdef SELECT_SECTION
862 SELECT_SECTION (decl
, reloc
);
864 if (TREE_READONLY (decl
)
865 && ! TREE_THIS_VOLATILE (decl
)
866 && ! (flag_pic
&& reloc
))
867 readonly_data_section ();
872 /* Compute and output the alignment of this data. */
874 align
= DECL_ALIGN (decl
);
875 /* Some object file formats have a maximum alignment which they support.
876 In particular, a.out format supports a maximum alignment of 4. */
877 #ifndef MAX_OFILE_ALIGNMENT
878 #define MAX_OFILE_ALIGNMENT BIGGEST_ALIGNMENT
880 if (align
> MAX_OFILE_ALIGNMENT
)
882 warning_with_decl (decl
,
883 "alignment of `%s' is greater than maximum object file alignment");
884 align
= MAX_OFILE_ALIGNMENT
;
886 #ifdef DATA_ALIGNMENT
887 /* On some machines, it is good to increase alignment sometimes. */
888 align
= DATA_ALIGNMENT (TREE_TYPE (decl
), align
);
890 #ifdef CONSTANT_ALIGNMENT
891 if (DECL_INITIAL (decl
))
892 align
= CONSTANT_ALIGNMENT (DECL_INITIAL (decl
), align
);
895 /* Reset the alignment in case we have made it tighter, so we can benefit
896 from it in get_pointer_alignment. */
897 DECL_ALIGN (decl
) = align
;
899 if (align
> BITS_PER_UNIT
)
900 ASM_OUTPUT_ALIGN (asm_out_file
, floor_log2 (align
/ BITS_PER_UNIT
));
902 /* Do any machine/system dependent processing of the object. */
903 #ifdef ASM_DECLARE_OBJECT_NAME
904 ASM_DECLARE_OBJECT_NAME (asm_out_file
, name
, decl
);
906 /* Standard thing is just output label for the object. */
907 ASM_OUTPUT_LABEL (asm_out_file
, name
);
908 #endif /* ASM_DECLARE_OBJECT_NAME */
911 for (d
= equivalents
; d
; d
= TREE_CHAIN (d
))
913 tree e
= TREE_VALUE (d
);
914 ASM_OUTPUT_LABEL (asm_out_file
, XSTR (XEXP (DECL_RTL (e
), 0), 0));
918 if (DECL_INITIAL (decl
))
919 /* Output the actual data. */
920 output_constant (DECL_INITIAL (decl
),
921 int_size_in_bytes (TREE_TYPE (decl
)));
923 /* Leave space for it. */
924 assemble_zeros (int_size_in_bytes (TREE_TYPE (decl
)));
927 #ifdef XCOFF_DEBUGGING_INFO
928 /* Unfortunately, the IBM assembler cannot handle stabx before the actual
929 declaration. When something like ".stabx "aa:S-2",aa,133,0" is emitted
930 and `aa' hasn't been output yet, the assembler generates a stab entry with
931 a value of zero, in addition to creating an unnecessary external entry
932 for `aa'. Hence, we must pospone dbxout_symbol to here at the end. */
934 /* File-scope global variables are output here. */
935 if (write_symbols
== XCOFF_DEBUG
&& top_level
)
936 dbxout_symbol (decl
, 0);
938 /* There must be a statement after a label. */
943 /* Output something to declare an external symbol to the assembler.
944 (Most assemblers don't need this, so we normally output nothing.)
945 Do nothing if DECL is not external. */
948 assemble_external (decl
)
951 #ifdef ASM_OUTPUT_EXTERNAL
952 if (TREE_CODE_CLASS (TREE_CODE (decl
)) == 'd'
953 && TREE_EXTERNAL (decl
) && TREE_PUBLIC (decl
))
955 rtx rtl
= DECL_RTL (decl
);
957 if (GET_CODE (rtl
) == MEM
&& GET_CODE (XEXP (rtl
, 0)) == SYMBOL_REF
958 && ! SYMBOL_REF_USED (XEXP (rtl
, 0)))
960 /* Some systems do require some output. */
961 SYMBOL_REF_USED (XEXP (rtl
, 0)) = 1;
962 ASM_OUTPUT_EXTERNAL (asm_out_file
, decl
, XSTR (XEXP (rtl
, 0), 0));
968 /* Similar, for calling a library function FUN. */
971 assemble_external_libcall (fun
)
974 #ifdef ASM_OUTPUT_EXTERNAL_LIBCALL
975 /* Declare library function name external when first used, if nec. */
976 if (! SYMBOL_REF_USED (fun
))
978 SYMBOL_REF_USED (fun
) = 1;
979 ASM_OUTPUT_EXTERNAL_LIBCALL (asm_out_file
, fun
);
984 /* Declare the label NAME global. */
987 assemble_global (name
)
990 ASM_GLOBALIZE_LABEL (asm_out_file
, name
);
993 /* Assemble a label named NAME. */
996 assemble_label (name
)
999 ASM_OUTPUT_LABEL (asm_out_file
, name
);
1002 /* Output to FILE a reference to the assembler name of a C-level name NAME.
1003 If NAME starts with a *, the rest of NAME is output verbatim.
1004 Otherwise NAME is transformed in an implementation-defined way
1005 (usually by the addition of an underscore).
1006 Many macros in the tm file are defined to call this function. */
1009 assemble_name (file
, name
)
1014 fputs (&name
[1], file
);
1016 ASM_OUTPUT_LABELREF (file
, name
);
1019 /* Allocate SIZE bytes writable static space with a gensym name
1020 and return an RTX to refer to its address. */
1023 assemble_static_space (size
)
1029 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1030 so that each uninitialized object starts on such a boundary. */
1031 int rounded
= ((size
+ (BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
) - 1)
1032 / (BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
)
1033 * (BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
));
1036 if (flag_shared_data
)
1040 ASM_GENERATE_INTERNAL_LABEL (name
, "LF", const_labelno
);
1043 namestring
= (char *) obstack_alloc (saveable_obstack
,
1045 strcpy (namestring
, name
);
1047 x
= gen_rtx (SYMBOL_REF
, Pmode
, namestring
);
1048 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
1049 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file
, name
, size
, BIGGEST_ALIGNMENT
);
1051 ASM_OUTPUT_LOCAL (asm_out_file
, name
, size
, rounded
);
1056 /* Assemble the static constant template for function entry trampolines.
1057 This is done at most once per compilation.
1058 Returns an RTX for the address of the template. */
1061 assemble_trampoline_template ()
1067 /* Write the assembler code to define one. */
1068 align
= floor_log2 (FUNCTION_BOUNDARY
/ BITS_PER_UNIT
);
1070 ASM_OUTPUT_ALIGN (asm_out_file
, align
);
1072 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file
, "LTRAMP", 0);
1073 TRAMPOLINE_TEMPLATE (asm_out_file
);
1075 /* Record the rtl to refer to it. */
1076 ASM_GENERATE_INTERNAL_LABEL (label
, "LTRAMP", 0);
1078 = (char *) obstack_copy0 (&permanent_obstack
, label
, strlen (label
));
1079 return gen_rtx (SYMBOL_REF
, Pmode
, name
);
1082 /* Assemble the integer constant X into an object of SIZE bytes.
1083 X must be either a CONST_INT or CONST_DOUBLE.
1085 Return 1 if we were able to output the constant, otherwise 0. If FORCE is
1086 non-zero, abort if we can't output the constant. */
1089 assemble_integer (x
, size
, force
)
1094 /* First try to use the standard 1, 2, 4, 8, and 16 byte
1095 ASM_OUTPUT... macros. */
1099 #ifdef ASM_OUTPUT_CHAR
1101 ASM_OUTPUT_CHAR (asm_out_file
, x
);
1105 #ifdef ASM_OUTPUT_SHORT
1107 ASM_OUTPUT_SHORT (asm_out_file
, x
);
1111 #ifdef ASM_OUTPUT_INT
1113 ASM_OUTPUT_INT (asm_out_file
, x
);
1117 #ifdef ASM_OUTPUT_DOUBLE_INT
1119 ASM_OUTPUT_DOUBLE_INT (asm_out_file
, x
);
1123 #ifdef ASM_OUTPUT_QUADRUPLE_INT
1125 ASM_OUTPUT_QUADRUPLE_INT (asm_out_file
, x
);
1130 /* If we couldn't do it that way, there are two other possibilities: First,
1131 if the machine can output an explicit byte and this is a 1 byte constant,
1132 we can use ASM_OUTPUT_BYTE. */
1134 #ifdef ASM_OUTPUT_BYTE
1135 if (size
== 1 && GET_CODE (x
) == CONST_INT
)
1137 ASM_OUTPUT_BYTE (asm_out_file
, INTVAL (x
));
1142 /* Finally, if SIZE is larger than a single word, try to output the constant
1143 one word at a time. */
1145 if (size
> UNITS_PER_WORD
)
1148 enum machine_mode mode
1149 = mode_for_size (size
* BITS_PER_UNIT
, MODE_INT
, 0);
1152 for (i
= 0; i
< size
/ UNITS_PER_WORD
; i
++)
1154 word
= operand_subword (x
, i
, 0, mode
);
1159 if (! assemble_integer (word
, UNITS_PER_WORD
, 0))
1163 if (i
== size
/ UNITS_PER_WORD
)
1165 /* If we output at least one word and then could not finish,
1166 there is no valid way to continue. */
1177 /* Assemble the floating-point constant D into an object of size MODE. */
1180 assemble_real (d
, mode
)
1182 enum machine_mode mode
;
1184 jmp_buf output_constant_handler
;
1186 if (setjmp (output_constant_handler
))
1188 error ("floating point trap outputting a constant");
1189 #ifdef REAL_IS_NOT_DOUBLE
1190 bzero (&d
, sizeof d
);
1197 set_float_handler (output_constant_handler
);
1201 #ifdef ASM_OUTPUT_FLOAT
1203 ASM_OUTPUT_FLOAT (asm_out_file
, d
);
1207 #ifdef ASM_OUTPUT_DOUBLE
1209 ASM_OUTPUT_DOUBLE (asm_out_file
, d
);
1213 #ifdef ASM_OUTPUT_LONG_DOUBLE
1215 ASM_OUTPUT_LONG_DOUBLE (asm_out_file
, d
);
1223 set_float_handler (0);
1226 /* Here we combine duplicate floating constants to make
1227 CONST_DOUBLE rtx's, and force those out to memory when necessary. */
1229 /* Chain of all CONST_DOUBLE rtx's constructed for the current function.
1230 They are chained through the CONST_DOUBLE_CHAIN.
1231 A CONST_DOUBLE rtx has CONST_DOUBLE_MEM != cc0_rtx iff it is on this chain.
1232 In that case, CONST_DOUBLE_MEM is either a MEM,
1233 or const0_rtx if no MEM has been made for this CONST_DOUBLE yet. */
1235 static rtx const_double_chain
;
1237 /* Return a CONST_DOUBLE for a value specified as a pair of ints.
1238 For an integer, I0 is the low-order word and I1 is the high-order word.
1239 For a real number, I0 is the word with the low address
1240 and I1 is the word with the high address. */
1243 immed_double_const (i0
, i1
, mode
)
1245 enum machine_mode mode
;
1248 int in_current_obstack
;
1250 if (GET_MODE_CLASS (mode
) == MODE_INT
)
1252 /* We clear out all bits that don't belong in MODE, unless they and our
1253 sign bit are all one. So we get either a reasonable negative value
1254 or a reasonable unsigned value for this mode. */
1255 int width
= GET_MODE_BITSIZE (mode
);
1256 if (width
< HOST_BITS_PER_INT
1257 && ((i0
& ((-1) << (width
- 1))) != ((-1) << (width
- 1))))
1258 i0
&= (1 << width
) - 1, i1
= 0;
1259 else if (width
== HOST_BITS_PER_INT
1260 && ! (i1
== ~0 && i0
< 0))
1262 else if (width
> 2 * HOST_BITS_PER_INT
)
1263 /* We cannot represent this value as a constant. */
1266 /* If MODE fits within HOST_BITS_PER_INT, always use a CONST_INT.
1268 ??? Strictly speaking, this is wrong if we create a CONST_INT
1269 for a large unsigned constant with the size of MODE being
1270 HOST_BITS_PER_INT and later try to interpret that constant in a wider
1271 mode. In that case we will mis-interpret it as a negative number.
1273 Unfortunately, the only alternative is to make a CONST_DOUBLE
1274 for any constant in any mode if it is an unsigned constant larger
1275 than the maximum signed integer in an int on the host. However,
1276 doing this will break everyone that always expects to see a CONST_INT
1277 for SImode and smaller.
1279 We have always been making CONST_INTs in this case, so nothing new
1282 if (width
<= HOST_BITS_PER_INT
)
1283 i1
= (i0
< 0) ? ~0 : 0;
1285 /* If this integer fits in one word, return a CONST_INT. */
1286 if ((i1
== 0 && i0
>= 0)
1287 || (i1
== ~0 && i0
< 0))
1288 return gen_rtx (CONST_INT
, VOIDmode
, i0
);
1290 /* We use VOIDmode for integers. */
1294 /* Search the chain for an existing CONST_DOUBLE with the right value.
1295 If one is found, return it. */
1297 for (r
= const_double_chain
; r
; r
= CONST_DOUBLE_CHAIN (r
))
1298 if (CONST_DOUBLE_LOW (r
) == i0
&& CONST_DOUBLE_HIGH (r
) == i1
1299 && GET_MODE (r
) == mode
)
1302 /* No; make a new one and add it to the chain.
1304 We may be called by an optimizer which may be discarding any memory
1305 allocated during its processing (such as combine and loop). However,
1306 we will be leaving this constant on the chain, so we cannot tolerate
1307 freed memory. So switch to saveable_obstack for this allocation
1308 and then switch back if we were in current_obstack. */
1310 in_current_obstack
= rtl_in_saveable_obstack ();
1311 r
= gen_rtx (CONST_DOUBLE
, mode
, 0, i0
, i1
);
1312 if (in_current_obstack
)
1313 rtl_in_current_obstack ();
1315 CONST_DOUBLE_CHAIN (r
) = const_double_chain
;
1316 const_double_chain
= r
;
1318 /* Store const0_rtx in mem-slot since this CONST_DOUBLE is on the chain.
1319 Actual use of mem-slot is only through force_const_mem. */
1321 CONST_DOUBLE_MEM (r
) = const0_rtx
;
1326 /* Return a CONST_DOUBLE for a specified `double' value
1327 and machine mode. */
1330 immed_real_const_1 (d
, mode
)
1332 enum machine_mode mode
;
1334 union real_extract u
;
1336 int in_current_obstack
;
1338 /* Get the desired `double' value as a sequence of ints
1339 since that is how they are stored in a CONST_DOUBLE. */
1343 /* Detect special cases. */
1345 /* Avoid REAL_VALUES_EQUAL here in order to distinguish minus zero. */
1346 if (!bcmp (&dconst0
, &d
, sizeof d
))
1347 return CONST0_RTX (mode
);
1348 else if (REAL_VALUES_EQUAL (dconst1
, d
))
1349 return CONST1_RTX (mode
);
1351 if (sizeof u
== 2 * sizeof (int))
1352 return immed_double_const (u
.i
[0], u
.i
[1], mode
);
1354 /* The rest of this function handles the case where
1355 a float value requires more than 2 ints of space.
1356 It will be deleted as dead code on machines that don't need it. */
1358 /* Search the chain for an existing CONST_DOUBLE with the right value.
1359 If one is found, return it. */
1361 for (r
= const_double_chain
; r
; r
= CONST_DOUBLE_CHAIN (r
))
1362 if (! bcmp (&CONST_DOUBLE_LOW (r
), &u
, sizeof u
)
1363 && GET_MODE (r
) == mode
)
1366 /* No; make a new one and add it to the chain.
1368 We may be called by an optimizer which may be discarding any memory
1369 allocated during its processing (such as combine and loop). However,
1370 we will be leaving this constant on the chain, so we cannot tolerate
1371 freed memory. So switch to saveable_obstack for this allocation
1372 and then switch back if we were in current_obstack. */
1374 in_current_obstack
= rtl_in_saveable_obstack ();
1375 r
= rtx_alloc (CONST_DOUBLE
);
1377 bcopy (&u
, &CONST_DOUBLE_LOW (r
), sizeof u
);
1378 if (in_current_obstack
)
1379 rtl_in_current_obstack ();
1381 CONST_DOUBLE_CHAIN (r
) = const_double_chain
;
1382 const_double_chain
= r
;
1384 /* Store const0_rtx in CONST_DOUBLE_MEM since this CONST_DOUBLE is on the
1385 chain, but has not been allocated memory. Actual use of CONST_DOUBLE_MEM
1386 is only through force_const_mem. */
1388 CONST_DOUBLE_MEM (r
) = const0_rtx
;
1393 /* Return a CONST_DOUBLE rtx for a value specified by EXP,
1394 which must be a REAL_CST tree node. */
1397 immed_real_const (exp
)
1400 return immed_real_const_1 (TREE_REAL_CST (exp
), TYPE_MODE (TREE_TYPE (exp
)));
1403 /* At the end of a function, forget the memory-constants
1404 previously made for CONST_DOUBLEs. Mark them as not on real_constant_chain.
1405 Also clear out real_constant_chain and clear out all the chain-pointers. */
1408 clear_const_double_mem ()
1410 register rtx r
, next
;
1412 for (r
= const_double_chain
; r
; r
= next
)
1414 next
= CONST_DOUBLE_CHAIN (r
);
1415 CONST_DOUBLE_CHAIN (r
) = 0;
1416 CONST_DOUBLE_MEM (r
) = cc0_rtx
;
1418 const_double_chain
= 0;
1421 /* Given an expression EXP with a constant value,
1422 reduce it to the sum of an assembler symbol and an integer.
1423 Store them both in the structure *VALUE.
1424 Abort if EXP does not reduce. */
1433 decode_addr_const (exp
, value
)
1435 struct addr_const
*value
;
1437 register tree target
= TREE_OPERAND (exp
, 0);
1438 register int offset
= 0;
1443 if (TREE_CODE (target
) == COMPONENT_REF
1444 && (TREE_CODE (DECL_FIELD_BITPOS (TREE_OPERAND (target
, 1)))
1447 offset
+= TREE_INT_CST_LOW (DECL_FIELD_BITPOS (TREE_OPERAND (target
, 1))) / BITS_PER_UNIT
;
1448 target
= TREE_OPERAND (target
, 0);
1450 else if (TREE_CODE (target
) == ARRAY_REF
)
1452 if (TREE_CODE (TREE_OPERAND (target
, 1)) != INTEGER_CST
1453 || TREE_CODE (TYPE_SIZE (TREE_TYPE (target
))) != INTEGER_CST
)
1455 offset
+= ((TREE_INT_CST_LOW (TYPE_SIZE (TREE_TYPE (target
)))
1456 * TREE_INT_CST_LOW (TREE_OPERAND (target
, 1)))
1458 target
= TREE_OPERAND (target
, 0);
1464 switch (TREE_CODE (target
))
1468 x
= DECL_RTL (target
);
1472 x
= gen_rtx (MEM
, FUNCTION_MODE
,
1473 gen_rtx (LABEL_REF
, VOIDmode
,
1474 label_rtx (TREE_OPERAND (exp
, 0))));
1481 x
= TREE_CST_RTL (target
);
1488 if (GET_CODE (x
) != MEM
)
1493 value
->offset
= offset
;
1496 /* Uniquize all constants that appear in memory.
1497 Each constant in memory thus far output is recorded
1498 in `const_hash_table' with a `struct constant_descriptor'
1499 that contains a polish representation of the value of
1502 We cannot store the trees in the hash table
1503 because the trees may be temporary. */
1505 struct constant_descriptor
1507 struct constant_descriptor
*next
;
1513 #define MAX_HASH_TABLE 1009
1514 static struct constant_descriptor
*const_hash_table
[MAX_HASH_TABLE
];
1516 /* Compute a hash code for a constant expression. */
1523 register int len
, hi
, i
;
1524 register enum tree_code code
= TREE_CODE (exp
);
1526 if (code
== INTEGER_CST
)
1528 p
= (char *) &TREE_INT_CST_LOW (exp
);
1529 len
= 2 * sizeof TREE_INT_CST_LOW (exp
);
1531 else if (code
== REAL_CST
)
1533 p
= (char *) &TREE_REAL_CST (exp
);
1534 len
= sizeof TREE_REAL_CST (exp
);
1536 else if (code
== STRING_CST
)
1537 p
= TREE_STRING_POINTER (exp
), len
= TREE_STRING_LENGTH (exp
);
1538 else if (code
== COMPLEX_CST
)
1539 return const_hash (TREE_REALPART (exp
)) * 5
1540 + const_hash (TREE_IMAGPART (exp
));
1541 else if (code
== CONSTRUCTOR
)
1545 /* For record type, include the type in the hashing.
1546 We do not do so for array types
1547 because (1) the sizes of the elements are sufficient
1548 and (2) distinct array types can have the same constructor. */
1549 if (TREE_CODE (TREE_TYPE (exp
)) == RECORD_TYPE
)
1550 hi
= ((int) TREE_TYPE (exp
) & ((1 << HASHBITS
) - 1)) % MAX_HASH_TABLE
;
1554 for (link
= CONSTRUCTOR_ELTS (exp
); link
; link
= TREE_CHAIN (link
))
1555 hi
= (hi
* 603 + const_hash (TREE_VALUE (link
))) % MAX_HASH_TABLE
;
1559 else if (code
== ADDR_EXPR
)
1561 struct addr_const value
;
1562 decode_addr_const (exp
, &value
);
1563 if (GET_CODE (value
.base
) == SYMBOL_REF
)
1565 /* Don't hash the address of the SYMBOL_REF;
1566 only use the offset and the symbol name. */
1568 p
= XSTR (value
.base
, 0);
1569 for (i
= 0; p
[i
] != 0; i
++)
1570 hi
= ((hi
* 613) + (unsigned)(p
[i
]));
1572 else if (GET_CODE (value
.base
) == LABEL_REF
)
1573 hi
= value
.offset
+ CODE_LABEL_NUMBER (XEXP (value
.base
, 0)) * 13;
1575 hi
&= (1 << HASHBITS
) - 1;
1576 hi
%= MAX_HASH_TABLE
;
1579 else if (code
== PLUS_EXPR
|| code
== MINUS_EXPR
)
1580 return const_hash (TREE_OPERAND (exp
, 0)) * 9
1581 + const_hash (TREE_OPERAND (exp
, 1));
1582 else if (code
== NOP_EXPR
|| code
== CONVERT_EXPR
)
1583 return const_hash (TREE_OPERAND (exp
, 0)) * 7 + 2;
1585 /* Compute hashing function */
1587 for (i
= 0; i
< len
; i
++)
1588 hi
= ((hi
* 613) + (unsigned)(p
[i
]));
1590 hi
&= (1 << HASHBITS
) - 1;
1591 hi
%= MAX_HASH_TABLE
;
1595 /* Compare a constant expression EXP with a constant-descriptor DESC.
1596 Return 1 if DESC describes a constant with the same value as EXP. */
1599 compare_constant (exp
, desc
)
1601 struct constant_descriptor
*desc
;
1603 return 0 != compare_constant_1 (exp
, desc
->contents
);
1606 /* Compare constant expression EXP with a substring P of a constant descriptor.
1607 If they match, return a pointer to the end of the substring matched.
1608 If they do not match, return 0.
1610 Since descriptors are written in polish prefix notation,
1611 this function can be used recursively to test one operand of EXP
1612 against a subdescriptor, and if it succeeds it returns the
1613 address of the subdescriptor for the next operand. */
1616 compare_constant_1 (exp
, p
)
1620 register char *strp
;
1622 register enum tree_code code
= TREE_CODE (exp
);
1624 if (code
!= (enum tree_code
) *p
++)
1627 if (code
== INTEGER_CST
)
1629 /* Integer constants are the same only if the same width of type. */
1630 if (*p
++ != TYPE_PRECISION (TREE_TYPE (exp
)))
1632 strp
= (char *) &TREE_INT_CST_LOW (exp
);
1633 len
= 2 * sizeof TREE_INT_CST_LOW (exp
);
1635 else if (code
== REAL_CST
)
1637 /* Real constants are the same only if the same width of type. */
1638 if (*p
++ != TYPE_PRECISION (TREE_TYPE (exp
)))
1640 strp
= (char *) &TREE_REAL_CST (exp
);
1641 len
= sizeof TREE_REAL_CST (exp
);
1643 else if (code
== STRING_CST
)
1645 if (flag_writable_strings
)
1647 strp
= TREE_STRING_POINTER (exp
);
1648 len
= TREE_STRING_LENGTH (exp
);
1649 if (bcmp (&TREE_STRING_LENGTH (exp
), p
,
1650 sizeof TREE_STRING_LENGTH (exp
)))
1652 p
+= sizeof TREE_STRING_LENGTH (exp
);
1654 else if (code
== COMPLEX_CST
)
1656 p
= compare_constant_1 (TREE_REALPART (exp
), p
);
1657 if (p
== 0) return 0;
1658 p
= compare_constant_1 (TREE_IMAGPART (exp
), p
);
1661 else if (code
== CONSTRUCTOR
)
1664 int length
= list_length (CONSTRUCTOR_ELTS (exp
));
1667 if (bcmp (&length
, p
, sizeof length
))
1671 /* For record constructors, insist that the types match.
1672 For arrays, just verify both constructors are for arrays. */
1673 if (TREE_CODE (TREE_TYPE (exp
)) == RECORD_TYPE
)
1674 type
= TREE_TYPE (exp
);
1677 if (bcmp (&type
, p
, sizeof type
))
1681 for (link
= CONSTRUCTOR_ELTS (exp
); link
; link
= TREE_CHAIN (link
))
1682 if ((p
= compare_constant_1 (TREE_VALUE (link
), p
)) == 0)
1686 else if (code
== ADDR_EXPR
)
1688 struct addr_const value
;
1689 decode_addr_const (exp
, &value
);
1690 strp
= (char *) &value
.offset
;
1691 len
= sizeof value
.offset
;
1692 /* Compare the offset. */
1694 if (*p
++ != *strp
++)
1696 /* Compare symbol name. */
1697 strp
= XSTR (value
.base
, 0);
1698 len
= strlen (strp
) + 1;
1700 else if (code
== PLUS_EXPR
|| code
== MINUS_EXPR
)
1702 p
= compare_constant_1 (TREE_OPERAND (exp
, 0), p
);
1703 if (p
== 0) return 0;
1704 p
= compare_constant_1 (TREE_OPERAND (exp
, 1), p
);
1707 else if (code
== NOP_EXPR
|| code
== CONVERT_EXPR
)
1709 p
= compare_constant_1 (TREE_OPERAND (exp
, 0), p
);
1713 /* Compare constant contents. */
1715 if (*p
++ != *strp
++)
1721 /* Construct a constant descriptor for the expression EXP.
1722 It is up to the caller to enter the descriptor in the hash table. */
1724 static struct constant_descriptor
*
1725 record_constant (exp
)
1728 struct constant_descriptor
*ptr
= 0;
1731 obstack_grow (&permanent_obstack
, &ptr
, sizeof ptr
);
1732 obstack_grow (&permanent_obstack
, &buf
, sizeof buf
);
1733 record_constant_1 (exp
);
1734 return (struct constant_descriptor
*) obstack_finish (&permanent_obstack
);
1737 /* Add a description of constant expression EXP
1738 to the object growing in `permanent_obstack'.
1739 No need to return its address; the caller will get that
1740 from the obstack when the object is complete. */
1743 record_constant_1 (exp
)
1746 register char *strp
;
1748 register enum tree_code code
= TREE_CODE (exp
);
1750 obstack_1grow (&permanent_obstack
, (unsigned int) code
);
1752 if (code
== INTEGER_CST
)
1754 obstack_1grow (&permanent_obstack
, TYPE_PRECISION (TREE_TYPE (exp
)));
1755 strp
= (char *) &TREE_INT_CST_LOW (exp
);
1756 len
= 2 * sizeof TREE_INT_CST_LOW (exp
);
1758 else if (code
== REAL_CST
)
1760 obstack_1grow (&permanent_obstack
, TYPE_PRECISION (TREE_TYPE (exp
)));
1761 strp
= (char *) &TREE_REAL_CST (exp
);
1762 len
= sizeof TREE_REAL_CST (exp
);
1764 else if (code
== STRING_CST
)
1766 if (flag_writable_strings
)
1768 strp
= TREE_STRING_POINTER (exp
);
1769 len
= TREE_STRING_LENGTH (exp
);
1770 obstack_grow (&permanent_obstack
, (char *) &TREE_STRING_LENGTH (exp
),
1771 sizeof TREE_STRING_LENGTH (exp
));
1773 else if (code
== COMPLEX_CST
)
1775 record_constant_1 (TREE_REALPART (exp
));
1776 record_constant_1 (TREE_IMAGPART (exp
));
1779 else if (code
== CONSTRUCTOR
)
1782 int length
= list_length (CONSTRUCTOR_ELTS (exp
));
1785 obstack_grow (&permanent_obstack
, (char *) &length
, sizeof length
);
1787 /* For record constructors, insist that the types match.
1788 For arrays, just verify both constructors are for arrays. */
1789 if (TREE_CODE (TREE_TYPE (exp
)) == RECORD_TYPE
)
1790 type
= TREE_TYPE (exp
);
1793 obstack_grow (&permanent_obstack
, (char *) &type
, sizeof type
);
1795 for (link
= CONSTRUCTOR_ELTS (exp
); link
; link
= TREE_CHAIN (link
))
1796 record_constant_1 (TREE_VALUE (link
));
1799 else if (code
== ADDR_EXPR
)
1801 struct addr_const value
;
1802 decode_addr_const (exp
, &value
);
1803 /* Record the offset. */
1804 obstack_grow (&permanent_obstack
,
1805 (char *) &value
.offset
, sizeof value
.offset
);
1806 /* Record the symbol name. */
1807 obstack_grow (&permanent_obstack
, XSTR (value
.base
, 0),
1808 strlen (XSTR (value
.base
, 0)) + 1);
1811 else if (code
== PLUS_EXPR
|| code
== MINUS_EXPR
)
1813 record_constant_1 (TREE_OPERAND (exp
, 0));
1814 record_constant_1 (TREE_OPERAND (exp
, 1));
1817 else if (code
== NOP_EXPR
|| code
== CONVERT_EXPR
)
1819 record_constant_1 (TREE_OPERAND (exp
, 0));
1823 /* Record constant contents. */
1824 obstack_grow (&permanent_obstack
, strp
, len
);
1827 /* Return an rtx representing a reference to constant data in memory
1828 for the constant expression EXP.
1829 If assembler code for such a constant has already been output,
1830 return an rtx to refer to it.
1831 Otherwise, output such a constant in memory and generate
1832 an rtx for it. The TREE_CST_RTL of EXP is set up to point to that rtx.
1833 The const_hash_table records which constants already have label strings. */
1836 output_constant_def (exp
)
1839 register int hash
, align
;
1840 register struct constant_descriptor
*desc
;
1846 if (TREE_CODE (exp
) == INTEGER_CST
)
1847 abort (); /* No TREE_CST_RTL slot in these. */
1849 if (TREE_CST_RTL (exp
))
1850 return TREE_CST_RTL (exp
);
1852 /* Make sure any other constants whose addresses appear in EXP
1853 are assigned label numbers. */
1855 reloc
= output_addressed_constants (exp
);
1857 /* Compute hash code of EXP. Search the descriptors for that hash code
1858 to see if any of them describes EXP. If yes, the descriptor records
1859 the label number already assigned. */
1861 hash
= const_hash (exp
) % MAX_HASH_TABLE
;
1863 for (desc
= const_hash_table
[hash
]; desc
; desc
= desc
->next
)
1864 if (compare_constant (exp
, desc
))
1866 found
= desc
->label
;
1872 /* No constant equal to EXP is known to have been output.
1873 Make a constant descriptor to enter EXP in the hash table.
1874 Assign the label number and record it in the descriptor for
1875 future calls to this function to find. */
1877 /* Create a string containing the label name, in LABEL. */
1878 ASM_GENERATE_INTERNAL_LABEL (label
, "LC", const_labelno
);
1880 desc
= record_constant (exp
);
1881 desc
->next
= const_hash_table
[hash
];
1883 = (char *) obstack_copy0 (&permanent_obstack
, label
, strlen (label
));
1884 const_hash_table
[hash
] = desc
;
1887 /* We have a symbol name; construct the SYMBOL_REF and the MEM. */
1889 push_obstacks_nochange ();
1890 if (TREE_PERMANENT (exp
))
1891 end_temporary_allocation ();
1893 def
= gen_rtx (SYMBOL_REF
, Pmode
, desc
->label
);
1896 = gen_rtx (MEM
, TYPE_MODE (TREE_TYPE (exp
)), def
);
1897 RTX_UNCHANGING_P (TREE_CST_RTL (exp
)) = 1;
1901 /* Optionally set flags or add text to the name to record information
1902 such as that it is a function name. If the name is changed, the macro
1903 ASM_OUTPUT_LABELREF will have to know how to strip this information.
1904 And if it finds a * at the beginning after doing so, it must handle
1906 #ifdef ENCODE_SECTION_INFO
1907 ENCODE_SECTION_INFO (exp
);
1912 /* Now output assembler code to define that label
1913 and follow it with the data of EXP. */
1915 /* First switch to text section, except for writable strings. */
1916 #ifdef SELECT_SECTION
1917 SELECT_SECTION (exp
, reloc
);
1919 if (((TREE_CODE (exp
) == STRING_CST
) && flag_writable_strings
)
1920 || (flag_pic
&& reloc
))
1923 readonly_data_section ();
1926 /* Align the location counter as required by EXP's data type. */
1927 align
= TYPE_ALIGN (TREE_TYPE (exp
));
1928 #ifdef CONSTANT_ALIGNMENT
1929 align
= CONSTANT_ALIGNMENT (exp
, align
);
1932 if (align
> BITS_PER_UNIT
)
1933 ASM_OUTPUT_ALIGN (asm_out_file
, floor_log2 (align
/ BITS_PER_UNIT
));
1935 /* Output the label itself. */
1936 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file
, "LC", const_labelno
);
1938 /* Output the value of EXP. */
1939 output_constant (exp
,
1940 (TREE_CODE (exp
) == STRING_CST
1941 ? TREE_STRING_LENGTH (exp
)
1942 : int_size_in_bytes (TREE_TYPE (exp
))));
1947 return TREE_CST_RTL (exp
);
1950 /* Similar hash facility for making memory-constants
1951 from constant rtl-expressions. It is used on RISC machines
1952 where immediate integer arguments and constant addresses are restricted
1953 so that such constants must be stored in memory.
1955 This pool of constants is reinitialized for each function
1956 so each function gets its own constants-pool that comes right before it.
1958 All structures allocated here are discarded when functions are saved for
1959 inlining, so they do not need to be allocated permanently. */
1961 #define MAX_RTX_HASH_TABLE 61
1962 static struct constant_descriptor
*const_rtx_hash_table
[MAX_RTX_HASH_TABLE
];
1964 /* Structure to represent sufficient information about a constant so that
1965 it can be output when the constant pool is output, so that function
1966 integration can be done, and to simplify handling on machines that reference
1967 constant pool as base+displacement. */
1969 struct pool_constant
1971 struct constant_descriptor
*desc
;
1972 struct pool_constant
*next
;
1973 enum machine_mode mode
;
1980 /* Pointers to first and last constant in pool. */
1982 static struct pool_constant
*first_pool
, *last_pool
;
1984 /* Current offset in constant pool (does not include any machine-specific
1987 static int pool_offset
;
1989 /* Structure used to maintain hash table mapping symbols used to their
1990 corresponding constants. */
1995 struct pool_constant
*pool
;
1996 struct pool_sym
*next
;
1999 static struct pool_sym
*const_rtx_sym_hash_table
[MAX_RTX_HASH_TABLE
];
2001 /* Hash code for a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true.
2002 The argument is XSTR (... , 0) */
2004 #define SYMHASH(LABEL) \
2005 ((((int) (LABEL)) & ((1 << HASHBITS) - 1)) % MAX_RTX_HASH_TABLE)
2007 /* Initialize constant pool hashing for next function. */
2010 init_const_rtx_hash_table ()
2012 bzero (const_rtx_hash_table
, sizeof const_rtx_hash_table
);
2013 bzero (const_rtx_sym_hash_table
, sizeof const_rtx_sym_hash_table
);
2015 first_pool
= last_pool
= 0;
2019 enum kind
{ RTX_DOUBLE
, RTX_INT
};
2023 #ifdef ONLY_INT_FIELDS
2024 unsigned int kind
: 16;
2025 unsigned int mode
: 16;
2027 enum kind kind
: 16;
2028 enum machine_mode mode
: 16;
2031 union real_extract du
;
2032 struct addr_const addr
;
2036 /* Express an rtx for a constant integer (perhaps symbolic)
2037 as the sum of a symbol or label plus an explicit integer.
2038 They are stored into VALUE. */
2041 decode_rtx_const (mode
, x
, value
)
2042 enum machine_mode mode
;
2044 struct rtx_const
*value
;
2046 /* Clear the whole structure, including any gaps. */
2049 int *p
= (int *) value
;
2050 int *end
= (int *) (value
+ 1);
2055 value
->kind
= RTX_INT
; /* Most usual kind. */
2058 switch (GET_CODE (x
))
2061 value
->kind
= RTX_DOUBLE
;
2062 value
->mode
= GET_MODE (x
);
2063 bcopy (&CONST_DOUBLE_LOW (x
), &value
->un
.du
, sizeof value
->un
.du
);
2067 value
->un
.addr
.offset
= INTVAL (x
);
2072 value
->un
.addr
.base
= x
;
2077 if (GET_CODE (x
) == PLUS
)
2079 value
->un
.addr
.base
= XEXP (x
, 0);
2080 if (GET_CODE (XEXP (x
, 1)) != CONST_INT
)
2082 value
->un
.addr
.offset
= INTVAL (XEXP (x
, 1));
2084 else if (GET_CODE (x
) == MINUS
)
2086 value
->un
.addr
.base
= XEXP (x
, 0);
2087 if (GET_CODE (XEXP (x
, 1)) != CONST_INT
)
2089 value
->un
.addr
.offset
= - INTVAL (XEXP (x
, 1));
2099 if (value
->kind
== RTX_INT
&& value
->un
.addr
.base
!= 0)
2100 switch (GET_CODE (value
->un
.addr
.base
))
2104 /* Use the string's address, not the SYMBOL_REF's address,
2105 for the sake of addresses of library routines.
2106 For a LABEL_REF, compare labels. */
2107 value
->un
.addr
.base
= XEXP (value
->un
.addr
.base
, 0);
2111 /* Compute a hash code for a constant RTL expression. */
2114 const_hash_rtx (mode
, x
)
2115 enum machine_mode mode
;
2120 struct rtx_const value
;
2121 decode_rtx_const (mode
, x
, &value
);
2123 /* Compute hashing function */
2125 for (i
= 0; i
< sizeof value
/ sizeof (int); i
++)
2126 hi
+= ((int *) &value
)[i
];
2128 hi
&= (1 << HASHBITS
) - 1;
2129 hi
%= MAX_RTX_HASH_TABLE
;
2133 /* Compare a constant rtl object X with a constant-descriptor DESC.
2134 Return 1 if DESC describes a constant with the same value as X. */
2137 compare_constant_rtx (mode
, x
, desc
)
2138 enum machine_mode mode
;
2140 struct constant_descriptor
*desc
;
2142 register int *p
= (int *) desc
->contents
;
2145 struct rtx_const value
;
2147 decode_rtx_const (mode
, x
, &value
);
2148 strp
= (int *) &value
;
2149 len
= sizeof value
/ sizeof (int);
2151 /* Compare constant contents. */
2153 if (*p
++ != *strp
++)
2159 /* Construct a constant descriptor for the rtl-expression X.
2160 It is up to the caller to enter the descriptor in the hash table. */
2162 static struct constant_descriptor
*
2163 record_constant_rtx (mode
, x
)
2164 enum machine_mode mode
;
2167 struct constant_descriptor
*ptr
;
2169 struct rtx_const value
;
2171 decode_rtx_const (mode
, x
, &value
);
2173 obstack_grow (current_obstack
, &ptr
, sizeof ptr
);
2174 obstack_grow (current_obstack
, &label
, sizeof label
);
2176 /* Record constant contents. */
2177 obstack_grow (current_obstack
, &value
, sizeof value
);
2179 return (struct constant_descriptor
*) obstack_finish (current_obstack
);
2182 /* Given a constant rtx X, make (or find) a memory constant for its value
2183 and return a MEM rtx to refer to it in memory. */
2186 force_const_mem (mode
, x
)
2187 enum machine_mode mode
;
2191 register struct constant_descriptor
*desc
;
2196 /* If we want this CONST_DOUBLE in the same mode as it is in memory
2197 (this will always be true for floating CONST_DOUBLEs that have been
2198 placed in memory, but not for VOIDmode (integer) CONST_DOUBLEs),
2199 use the previous copy. Otherwise, make a new one. Note that in
2200 the unlikely event that this same CONST_DOUBLE is used in two different
2201 modes in an alternating fashion, we will allocate a lot of different
2202 memory locations, but this should be extremely rare. */
2204 if (GET_CODE (x
) == CONST_DOUBLE
2205 && GET_CODE (CONST_DOUBLE_MEM (x
)) == MEM
2206 && GET_MODE (CONST_DOUBLE_MEM (x
)) == mode
)
2207 return CONST_DOUBLE_MEM (x
);
2209 /* Compute hash code of X. Search the descriptors for that hash code
2210 to see if any of them describes X. If yes, the descriptor records
2211 the label number already assigned. */
2213 hash
= const_hash_rtx (mode
, x
);
2215 for (desc
= const_rtx_hash_table
[hash
]; desc
; desc
= desc
->next
)
2216 if (compare_constant_rtx (mode
, x
, desc
))
2218 found
= desc
->label
;
2224 register struct pool_constant
*pool
;
2225 register struct pool_sym
*sym
;
2228 /* No constant equal to X is known to have been output.
2229 Make a constant descriptor to enter X in the hash table.
2230 Assign the label number and record it in the descriptor for
2231 future calls to this function to find. */
2233 desc
= record_constant_rtx (mode
, x
);
2234 desc
->next
= const_rtx_hash_table
[hash
];
2235 const_rtx_hash_table
[hash
] = desc
;
2237 /* Align the location counter as required by EXP's data type. */
2238 align
= (mode
== VOIDmode
) ? UNITS_PER_WORD
: GET_MODE_SIZE (mode
);
2239 if (align
> BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
)
2240 align
= BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
;
2242 pool_offset
+= align
- 1;
2243 pool_offset
&= ~ (align
- 1);
2245 /* Allocate a pool constant descriptor, fill it in, and chain it in. */
2247 pool
= (struct pool_constant
*) oballoc (sizeof (struct pool_constant
));
2251 pool
->labelno
= const_labelno
;
2252 pool
->align
= align
;
2253 pool
->offset
= pool_offset
;
2259 last_pool
->next
= pool
;
2262 pool_offset
+= GET_MODE_SIZE (mode
);
2264 /* Create a string containing the label name, in LABEL. */
2265 ASM_GENERATE_INTERNAL_LABEL (label
, "LC", const_labelno
);
2270 = (char *) obstack_copy0 (saveable_obstack
, label
, strlen (label
));
2272 /* Add label to symbol hash table. */
2273 hash
= SYMHASH (found
);
2274 sym
= (struct pool_sym
*) oballoc (sizeof (struct pool_sym
));
2277 sym
->next
= const_rtx_sym_hash_table
[hash
];
2278 const_rtx_sym_hash_table
[hash
] = sym
;
2281 /* We have a symbol name; construct the SYMBOL_REF and the MEM. */
2283 def
= gen_rtx (MEM
, mode
, gen_rtx (SYMBOL_REF
, Pmode
, found
));
2285 RTX_UNCHANGING_P (def
) = 1;
2286 /* Mark the symbol_ref as belonging to this constants pool. */
2287 CONSTANT_POOL_ADDRESS_P (XEXP (def
, 0)) = 1;
2288 current_function_uses_const_pool
= 1;
2290 if (GET_CODE (x
) == CONST_DOUBLE
)
2292 if (CONST_DOUBLE_MEM (x
) == cc0_rtx
)
2294 CONST_DOUBLE_CHAIN (x
) = const_double_chain
;
2295 const_double_chain
= x
;
2297 CONST_DOUBLE_MEM (x
) = def
;
2303 /* Given a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true, return a pointer to
2304 the corresponding pool_constant structure. */
2306 static struct pool_constant
*
2307 find_pool_constant (addr
)
2310 struct pool_sym
*sym
;
2311 char *label
= XSTR (addr
, 0);
2313 for (sym
= const_rtx_sym_hash_table
[SYMHASH (label
)]; sym
; sym
= sym
->next
)
2314 if (sym
->label
== label
)
2320 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
2323 get_pool_constant (addr
)
2326 return (find_pool_constant (addr
))->constant
;
2329 /* Similar, return the mode. */
2332 get_pool_mode (addr
)
2335 return (find_pool_constant (addr
))->mode
;
2338 /* Similar, return the offset in the constant pool. */
2341 get_pool_offset (addr
)
2344 return (find_pool_constant (addr
))->offset
;
2347 /* Return the size of the constant pool. */
2355 /* Write all the constants in the constant pool. */
2358 output_constant_pool (fnname
, fndecl
)
2362 struct pool_constant
*pool
;
2364 union real_extract u
;
2366 #ifdef ASM_OUTPUT_POOL_PROLOGUE
2367 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file
, fnname
, fndecl
, pool_offset
);
2370 for (pool
= first_pool
; pool
; pool
= pool
->next
)
2374 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
2375 whose CODE_LABEL has been deleted. This can occur if a jump table
2376 is eliminated by optimization. If so, write a constant of zero
2378 if ((GET_CODE (x
) == LABEL_REF
&& INSN_DELETED_P (XEXP (x
, 0)))
2379 || (GET_CODE (x
) == CONST
&& GET_CODE (XEXP (x
, 0)) == PLUS
2380 && GET_CODE (XEXP (XEXP (x
, 0), 0)) == LABEL_REF
2381 && INSN_DELETED_P (XEXP (XEXP (XEXP (x
, 0), 0), 0))))
2384 /* First switch to correct section. */
2385 #ifdef SELECT_RTX_SECTION
2386 SELECT_RTX_SECTION (pool
->mode
, x
);
2388 readonly_data_section ();
2391 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
2392 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file
, x
, pool
->mode
,
2393 pool
->align
, pool
->labelno
, done
);
2396 if (pool
->align
> 1)
2397 ASM_OUTPUT_ALIGN (asm_out_file
, exact_log2 (pool
->align
));
2399 /* Output the label. */
2400 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file
, "LC", pool
->labelno
);
2402 /* Output the value of the constant itself. */
2403 switch (GET_MODE_CLASS (pool
->mode
))
2406 if (GET_CODE (x
) != CONST_DOUBLE
)
2409 bcopy (&CONST_DOUBLE_LOW (x
), &u
, sizeof u
);
2410 assemble_real (u
.d
, pool
->mode
);
2414 assemble_integer (x
, GET_MODE_SIZE (pool
->mode
), 1);
2424 /* Done with this pool. */
2425 first_pool
= last_pool
= 0;
2428 /* Find all the constants whose addresses are referenced inside of EXP,
2429 and make sure assembler code with a label has been output for each one.
2430 Indicate whether an ADDR_EXPR has been encountered. */
2433 output_addressed_constants (exp
)
2438 switch (TREE_CODE (exp
))
2442 register tree constant
= TREE_OPERAND (exp
, 0);
2444 while (TREE_CODE (constant
) == COMPONENT_REF
)
2446 constant
= TREE_OPERAND (constant
, 0);
2449 if (TREE_CODE_CLASS (TREE_CODE (constant
)) == 'c'
2450 || TREE_CODE (constant
) == CONSTRUCTOR
)
2451 /* No need to do anything here
2452 for addresses of variables or functions. */
2453 output_constant_def (constant
);
2460 reloc
= output_addressed_constants (TREE_OPERAND (exp
, 0));
2461 reloc
|= output_addressed_constants (TREE_OPERAND (exp
, 1));
2466 reloc
= output_addressed_constants (TREE_OPERAND (exp
, 0));
2472 for (link
= CONSTRUCTOR_ELTS (exp
); link
; link
= TREE_CHAIN (link
))
2473 if (TREE_VALUE (link
) != 0)
2474 reloc
|= output_addressed_constants (TREE_VALUE (link
));
2484 /* Output assembler code for constant EXP to FILE, with no label.
2485 This includes the pseudo-op such as ".int" or ".byte", and a newline.
2486 Assumes output_addressed_constants has been done on EXP already.
2488 Generate exactly SIZE bytes of assembler data, padding at the end
2489 with zeros if necessary. SIZE must always be specified.
2491 SIZE is important for structure constructors,
2492 since trailing members may have been omitted from the constructor.
2493 It is also important for initialization of arrays from string constants
2494 since the full length of the string constant might not be wanted.
2495 It is also needed for initialization of unions, where the initializer's
2496 type is just one member, and that may not be as long as the union.
2498 There a case in which we would fail to output exactly SIZE bytes:
2499 for a structure constructor that wants to produce more than SIZE bytes.
2500 But such constructors will never be generated for any possible input. */
2503 output_constant (exp
, size
)
2507 register enum tree_code code
= TREE_CODE (TREE_TYPE (exp
));
2513 /* Allow a constructor with no elements for any data type.
2514 This means to fill the space with zeros. */
2515 if (TREE_CODE (exp
) == CONSTRUCTOR
2516 && TREE_OPERAND (exp
, 1) == 0)
2518 assemble_zeros (size
);
2522 /* Eliminate the NOP_EXPR that makes a cast not be an lvalue.
2523 That way we get the constant (we hope) inside it. */
2524 if (TREE_CODE (exp
) == NOP_EXPR
2525 && TREE_TYPE (exp
) == TREE_TYPE (TREE_OPERAND (exp
, 0)))
2526 exp
= TREE_OPERAND (exp
, 0);
2533 case REFERENCE_TYPE
:
2534 /* ??? What about (int)((float)(int)&foo + 4) */
2535 while (TREE_CODE (exp
) == NOP_EXPR
|| TREE_CODE (exp
) == CONVERT_EXPR
2536 || TREE_CODE (exp
) == NON_LVALUE_EXPR
)
2537 exp
= TREE_OPERAND (exp
, 0);
2539 if (! assemble_integer (expand_expr (exp
, 0, VOIDmode
,
2540 EXPAND_INITIALIZER
),
2542 error ("initializer for integer value is too complicated");
2547 if (TREE_CODE (exp
) != REAL_CST
)
2548 error ("initializer for floating value is not a floating constant");
2550 assemble_real (TREE_REAL_CST (exp
),
2551 mode_for_size (size
* BITS_PER_UNIT
, MODE_FLOAT
, 0));
2556 output_constant (TREE_REALPART (exp
), size
/ 2);
2557 output_constant (TREE_IMAGPART (exp
), size
/ 2);
2558 size
-= (size
/ 2) * 2;
2562 if (TREE_CODE (exp
) == CONSTRUCTOR
)
2564 output_constructor (exp
, size
);
2567 else if (TREE_CODE (exp
) == STRING_CST
)
2571 if (size
> TREE_STRING_LENGTH (exp
))
2573 excess
= size
- TREE_STRING_LENGTH (exp
);
2574 size
= TREE_STRING_LENGTH (exp
);
2577 assemble_string (TREE_STRING_POINTER (exp
), size
);
2586 if (TREE_CODE (exp
) == CONSTRUCTOR
)
2587 output_constructor (exp
, size
);
2594 assemble_zeros (size
);
2597 /* Subroutine of output_constant, used for CONSTRUCTORs
2598 (aggregate constants).
2599 Generate at least SIZE bytes, padding if necessary. */
2602 output_constructor (exp
, size
)
2606 register tree link
, field
= 0;
2607 /* Number of bytes output or skipped so far.
2608 In other words, current position within the constructor. */
2609 int total_bytes
= 0;
2610 /* Non-zero means BYTE contains part of a byte, to be output. */
2611 int byte_buffer_in_use
= 0;
2614 if (HOST_BITS_PER_INT
< BITS_PER_UNIT
)
2617 if (TREE_CODE (TREE_TYPE (exp
)) == RECORD_TYPE
)
2618 field
= TYPE_FIELDS (TREE_TYPE (exp
));
2620 /* As LINK goes through the elements of the constant,
2621 FIELD goes through the structure fields, if the constant is a structure.
2622 if the constant is a union, then we override this,
2623 by getting the field from the TREE_LIST element.
2624 But the constant could also be an array. Then FIELD is zero. */
2625 for (link
= CONSTRUCTOR_ELTS (exp
);
2627 link
= TREE_CHAIN (link
),
2628 field
= field
? TREE_CHAIN (field
) : 0)
2630 tree val
= TREE_VALUE (link
);
2631 /* the element in a union constructor specifies the proper field. */
2632 if (TREE_PURPOSE (link
) != 0)
2633 field
= TREE_PURPOSE (link
);
2635 /* Eliminate the marker that makes a cast not be an lvalue. */
2636 if (val
!= 0 && TREE_CODE (val
) == NON_LVALUE_EXPR
)
2637 val
= TREE_OPERAND (val
, 0);
2639 if (field
== 0 || !DECL_BIT_FIELD (field
))
2641 register int fieldsize
;
2642 /* Since this structure is static,
2643 we know the positions are constant. */
2644 int bitpos
= (field
? (TREE_INT_CST_LOW (DECL_FIELD_BITPOS (field
))
2648 /* An element that is not a bit-field.
2649 Output any buffered-up bit-fields preceding it. */
2650 if (byte_buffer_in_use
)
2652 ASM_OUTPUT_BYTE (asm_out_file
, byte
);
2654 byte_buffer_in_use
= 0;
2657 /* Advance to offset of this element.
2658 Note no alignment needed in an array, since that is guaranteed
2659 if each element has the proper size. */
2660 if (field
!= 0 && bitpos
!= total_bytes
)
2662 assemble_zeros (bitpos
- total_bytes
);
2663 total_bytes
= bitpos
;
2666 /* Determine size this element should occupy. */
2669 if (TREE_CODE (DECL_SIZE (field
)) != INTEGER_CST
)
2671 if (TREE_INT_CST_LOW (DECL_SIZE (field
)) > 100000)
2673 /* This avoids overflow trouble. */
2674 tree size_tree
= size_binop (CEIL_DIV_EXPR
,
2676 size_int (BITS_PER_UNIT
));
2677 fieldsize
= TREE_INT_CST_LOW (size_tree
);
2681 fieldsize
= TREE_INT_CST_LOW (DECL_SIZE (field
));
2682 fieldsize
= (fieldsize
+ BITS_PER_UNIT
- 1) / BITS_PER_UNIT
;
2686 fieldsize
= int_size_in_bytes (TREE_TYPE (TREE_TYPE (exp
)));
2688 /* Output the element's initial value. */
2690 assemble_zeros (fieldsize
);
2692 output_constant (val
, fieldsize
);
2694 /* Count its size. */
2695 total_bytes
+= fieldsize
;
2697 else if (val
!= 0 && TREE_CODE (val
) != INTEGER_CST
)
2698 error ("invalid initial value for member `%s'",
2699 IDENTIFIER_POINTER (DECL_NAME (field
)));
2702 /* Element that is a bit-field. */
2704 int next_offset
= TREE_INT_CST_LOW (DECL_FIELD_BITPOS (field
));
2706 = (next_offset
+ TREE_INT_CST_LOW (DECL_SIZE (field
)));
2709 val
= integer_zero_node
;
2711 /* If this field does not start in this (or, next) byte,
2713 if (next_offset
/ BITS_PER_UNIT
!= total_bytes
)
2715 /* Output remnant of any bit field in previous bytes. */
2716 if (byte_buffer_in_use
)
2718 ASM_OUTPUT_BYTE (asm_out_file
, byte
);
2720 byte_buffer_in_use
= 0;
2723 /* If still not at proper byte, advance to there. */
2724 if (next_offset
/ BITS_PER_UNIT
!= total_bytes
)
2726 assemble_zeros (next_offset
/ BITS_PER_UNIT
- total_bytes
);
2727 total_bytes
= next_offset
/ BITS_PER_UNIT
;
2731 if (! byte_buffer_in_use
)
2734 /* We must split the element into pieces that fall within
2735 separate bytes, and combine each byte with previous or
2736 following bit-fields. */
2738 /* next_offset is the offset n fbits from the beginning of
2739 the structure to the next bit of this element to be processed.
2740 end_offset is the offset of the first bit past the end of
2742 while (next_offset
< end_offset
)
2746 int next_byte
= next_offset
/ BITS_PER_UNIT
;
2747 int next_bit
= next_offset
% BITS_PER_UNIT
;
2749 /* Advance from byte to byte
2750 within this element when necessary. */
2751 while (next_byte
!= total_bytes
)
2753 ASM_OUTPUT_BYTE (asm_out_file
, byte
);
2758 /* Number of bits we can process at once
2759 (all part of the same byte). */
2760 this_time
= MIN (end_offset
- next_offset
,
2761 BITS_PER_UNIT
- next_bit
);
2762 #if BYTES_BIG_ENDIAN
2763 /* On big-endian machine, take the most significant bits
2764 first (of the bits that are significant)
2765 and put them into bytes from the most significant end. */
2766 shift
= end_offset
- next_offset
- this_time
;
2767 /* Don't try to take a bunch of bits that cross
2768 the word boundary in the INTEGER_CST. */
2769 if (shift
< HOST_BITS_PER_INT
2770 && shift
+ this_time
> HOST_BITS_PER_INT
)
2772 this_time
-= (HOST_BITS_PER_INT
- shift
);
2773 shift
= HOST_BITS_PER_INT
;
2776 /* Now get the bits from the appropriate constant word. */
2777 if (shift
< HOST_BITS_PER_INT
)
2779 value
= TREE_INT_CST_LOW (val
);
2781 else if (shift
< 2 * HOST_BITS_PER_INT
)
2783 value
= TREE_INT_CST_HIGH (val
);
2784 shift
-= HOST_BITS_PER_INT
;
2788 byte
|= (((value
>> shift
) & ((1 << this_time
) - 1))
2789 << (BITS_PER_UNIT
- this_time
- next_bit
));
2791 /* On little-endian machines,
2792 take first the least significant bits of the value
2793 and pack them starting at the least significant
2794 bits of the bytes. */
2795 shift
= (next_offset
2796 - TREE_INT_CST_LOW (DECL_FIELD_BITPOS (field
)));
2797 /* Don't try to take a bunch of bits that cross
2798 the word boundary in the INTEGER_CST. */
2799 if (shift
< HOST_BITS_PER_INT
2800 && shift
+ this_time
> HOST_BITS_PER_INT
)
2802 this_time
-= (HOST_BITS_PER_INT
- shift
);
2803 shift
= HOST_BITS_PER_INT
;
2806 /* Now get the bits from the appropriate constant word. */
2807 if (shift
< HOST_BITS_PER_INT
)
2808 value
= TREE_INT_CST_LOW (val
);
2809 else if (shift
< 2 * HOST_BITS_PER_INT
)
2811 value
= TREE_INT_CST_HIGH (val
);
2812 shift
-= HOST_BITS_PER_INT
;
2816 byte
|= ((value
>> shift
) & ((1 << this_time
) - 1)) << next_bit
;
2818 next_offset
+= this_time
;
2819 byte_buffer_in_use
= 1;
2823 if (byte_buffer_in_use
)
2825 ASM_OUTPUT_BYTE (asm_out_file
, byte
);
2828 if (total_bytes
< size
)
2829 assemble_zeros (size
- total_bytes
);