1 /* Output variables, constants and external declarations, for GNU compiler.
2 Copyright (C) 1987, 88, 89, 92, 93, 94, 1995 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> */
38 #include "hard-reg-set.h"
46 #ifdef XCOFF_DEBUGGING_INFO
53 #define ASM_STABS_OP ".stabs"
56 /* This macro gets just the user-specified name
57 out of the string in a SYMBOL_REF. On most machines,
58 we discard the * if any and that's all. */
59 #ifndef STRIP_NAME_ENCODING
60 #define STRIP_NAME_ENCODING(VAR,SYMBOL_NAME) \
61 (VAR) = ((SYMBOL_NAME) + ((SYMBOL_NAME)[0] == '*'))
64 /* File in which assembler code is being written. */
66 extern FILE *asm_out_file;
68 /* The (assembler) name of the first globally-visible object output. */
69 char *first_global_object_name;
71 extern struct obstack *current_obstack;
72 extern struct obstack *saveable_obstack;
73 extern struct obstack *rtl_obstack;
74 extern struct obstack permanent_obstack;
75 #define obstack_chunk_alloc xmalloc
77 /* Number for making the label on the next
78 constant that is stored in memory. */
82 /* Number for making the label on the next
83 static variable internal to a function. */
87 /* Carry information from ASM_DECLARE_OBJECT_NAME
88 to ASM_FINISH_DECLARE_OBJECT. */
90 int size_directive_output;
92 /* The last decl for which assemble_variable was called,
93 if it did ASM_DECLARE_OBJECT_NAME.
94 If the last call to assemble_variable didn't do that,
97 tree last_assemble_variable_decl;
99 /* Nonzero if at least one function definition has been seen. */
100 static int function_defined;
103 struct constant_descriptor;
105 struct pool_constant;
107 static void bc_make_decl_rtl PROTO((tree, char *, int));
108 static char *strip_reg_name PROTO((char *));
109 static void bc_output_ascii PROTO((FILE *, char *, int));
110 static int contains_pointers_p PROTO((tree));
111 static void decode_addr_const PROTO((tree, struct addr_const *));
112 static int const_hash PROTO((tree));
113 static int compare_constant PROTO((tree,
114 struct constant_descriptor *));
115 static char *compare_constant_1 PROTO((tree, char *));
116 static struct constant_descriptor *record_constant PROTO((tree));
117 static void record_constant_1 PROTO((tree));
118 static tree copy_constant PROTO((tree));
119 static void output_constant_def_contents PROTO((tree, int, int));
120 static void decode_rtx_const PROTO((enum machine_mode, rtx,
121 struct rtx_const *));
122 static int const_hash_rtx PROTO((enum machine_mode, rtx));
123 static int compare_constant_rtx PROTO((enum machine_mode, rtx,
124 struct constant_descriptor *));
125 static struct constant_descriptor *record_constant_rtx PROTO((enum machine_mode,
127 static struct pool_constant *find_pool_constant PROTO((rtx));
128 static int output_addressed_constants PROTO((tree));
129 static void bc_assemble_integer PROTO((tree, int));
130 static void output_constructor PROTO((tree, int));
132 #ifdef EXTRA_SECTIONS
133 static enum in_section {no_section, in_text, in_data, in_named, EXTRA_SECTIONS} in_section
136 static enum in_section {no_section, in_text, in_data, in_named} in_section
140 /* Return a non-zero value if DECL has a section attribute. */
141 #define IN_NAMED_SECTION(DECL) \
142 ((TREE_CODE (DECL) == FUNCTION_DECL || TREE_CODE (DECL) == VAR_DECL) \
143 && DECL_SECTION_NAME (DECL) != NULL_TREE)
145 /* Text of section name when in_section == in_named. */
146 static char *in_named_name;
148 /* Define functions like text_section for any extra sections. */
149 #ifdef EXTRA_SECTION_FUNCTIONS
150 EXTRA_SECTION_FUNCTIONS
153 /* Tell assembler to switch to text section. */
158 if (in_section != in_text)
163 fprintf (asm_out_file, "%s\n", TEXT_SECTION_ASM_OP);
165 in_section = in_text;
169 /* Tell assembler to switch to data section. */
174 if (in_section != in_data)
180 if (flag_shared_data)
182 #ifdef SHARED_SECTION_ASM_OP
183 fprintf (asm_out_file, "%s\n", SHARED_SECTION_ASM_OP);
185 fprintf (asm_out_file, "%s\n", DATA_SECTION_ASM_OP);
189 fprintf (asm_out_file, "%s\n", DATA_SECTION_ASM_OP);
192 in_section = in_data;
196 /* Tell assembler to switch to read-only data section. This is normally
200 readonly_data_section ()
202 #ifdef READONLY_DATA_SECTION
203 READONLY_DATA_SECTION (); /* Note this can call data_section. */
209 /* Determine if we're in the text section. */
214 return in_section == in_text;
217 /* Tell assembler to change to section NAME for DECL.
218 If DECL is NULL, just switch to section NAME.
219 If NAME is NULL, get the name from DECL. */
222 named_section (decl, name)
226 if (decl != NULL_TREE
227 && (TREE_CODE (decl) != FUNCTION_DECL && TREE_CODE (decl) != VAR_DECL))
230 name = TREE_STRING_POINTER (DECL_SECTION_NAME (decl));
232 if (in_section != in_named || strcmp (name, in_named_name))
234 in_named_name = name;
235 in_section = in_named;
237 #ifdef ASM_OUTPUT_SECTION_NAME
238 ASM_OUTPUT_SECTION_NAME (asm_out_file, decl, name);
240 /* Section attributes are not supported if this macro isn't provided -
241 some host formats don't support them at all. The front-end should
242 already have flagged this as an error. */
248 /* Switch to the section for function DECL.
250 If DECL is NULL_TREE, switch to the text section.
251 ??? It's not clear that we will ever be passed NULL_TREE, but it's
252 safer to handle it. */
255 function_section (decl)
258 if (decl != NULL_TREE
259 && DECL_SECTION_NAME (decl) != NULL_TREE)
260 named_section (decl, (char *) 0);
265 /* Create the rtl to represent a function, for a function definition.
266 DECL is a FUNCTION_DECL node which describes which function.
267 The rtl is stored into DECL. */
270 make_function_rtl (decl)
273 char *name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
277 if (DECL_RTL (decl) == 0)
278 DECL_RTL (decl) = bc_gen_rtx (name, 0, (struct bc_label *) 0);
280 /* Record that at least one function has been defined. */
281 function_defined = 1;
285 /* Rename a nested function to avoid conflicts. */
286 if (decl_function_context (decl) != 0
287 && DECL_INITIAL (decl) != 0
288 && DECL_RTL (decl) == 0)
292 name = IDENTIFIER_POINTER (DECL_NAME (decl));
293 ASM_FORMAT_PRIVATE_NAME (label, name, var_labelno);
294 name = obstack_copy0 (saveable_obstack, label, strlen (label));
298 if (DECL_RTL (decl) == 0)
301 = gen_rtx (MEM, DECL_MODE (decl),
302 gen_rtx (SYMBOL_REF, Pmode, name));
304 /* Optionally set flags or add text to the name to record information
305 such as that it is a function name. If the name is changed, the macro
306 ASM_OUTPUT_LABELREF will have to know how to strip this information. */
307 #ifdef ENCODE_SECTION_INFO
308 ENCODE_SECTION_INFO (decl);
312 /* Record at least one function has been defined. */
313 function_defined = 1;
316 /* Create the DECL_RTL for a declaration for a static or external
317 variable or static or external function.
318 ASMSPEC, if not 0, is the string which the user specified
319 as the assembler symbol name.
320 TOP_LEVEL is nonzero if this is a file-scope variable.
321 This is never called for PARM_DECLs. */
324 bc_make_decl_rtl (decl, asmspec, top_level)
329 register char *name = TREE_STRING_POINTER (DECL_ASSEMBLER_NAME (decl));
331 if (DECL_RTL (decl) == 0)
333 /* Print an error message for register variables. */
334 if (DECL_REGISTER (decl) && TREE_CODE (decl) == FUNCTION_DECL)
335 error ("function declared `register'");
336 else if (DECL_REGISTER (decl))
337 error ("global register variables not supported in the interpreter");
339 /* Handle ordinary static variables and functions. */
340 if (DECL_RTL (decl) == 0)
342 /* Can't use just the variable's own name for a variable
343 whose scope is less than the whole file.
344 Concatenate a distinguishing number. */
345 if (!top_level && !DECL_EXTERNAL (decl) && asmspec == 0)
349 ASM_FORMAT_PRIVATE_NAME (label, name, var_labelno);
350 name = obstack_copy0 (saveable_obstack, label, strlen (label));
354 DECL_RTL (decl) = bc_gen_rtx (name, 0, (struct bc_label *) 0);
359 /* Given NAME, a putative register name, discard any customary prefixes. */
362 strip_reg_name (name)
365 #ifdef REGISTER_PREFIX
366 if (!strncmp (name, REGISTER_PREFIX, strlen (REGISTER_PREFIX)))
367 name += strlen (REGISTER_PREFIX);
369 if (name[0] == '%' || name[0] == '#')
374 /* Decode an `asm' spec for a declaration as a register name.
375 Return the register number, or -1 if nothing specified,
376 or -2 if the ASMSPEC is not `cc' or `memory' and is not recognized,
377 or -3 if ASMSPEC is `cc' and is not recognized,
378 or -4 if ASMSPEC is `memory' and is not recognized.
379 Accept an exact spelling or a decimal number.
380 Prefixes such as % are optional. */
383 decode_reg_name (asmspec)
390 /* Get rid of confusing prefixes. */
391 asmspec = strip_reg_name (asmspec);
393 /* Allow a decimal number as a "register name". */
394 for (i = strlen (asmspec) - 1; i >= 0; i--)
395 if (! (asmspec[i] >= '0' && asmspec[i] <= '9'))
397 if (asmspec[0] != 0 && i < 0)
400 if (i < FIRST_PSEUDO_REGISTER && i >= 0)
406 for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
408 && ! strcmp (asmspec, strip_reg_name (reg_names[i])))
411 #ifdef ADDITIONAL_REGISTER_NAMES
413 static struct { char *name; int number; } table[]
414 = ADDITIONAL_REGISTER_NAMES;
416 for (i = 0; i < sizeof (table) / sizeof (table[0]); i++)
417 if (! strcmp (asmspec, table[i].name))
418 return table[i].number;
420 #endif /* ADDITIONAL_REGISTER_NAMES */
422 if (!strcmp (asmspec, "memory"))
425 if (!strcmp (asmspec, "cc"))
434 /* Create the DECL_RTL for a declaration for a static or external variable
435 or static or external function.
436 ASMSPEC, if not 0, is the string which the user specified
437 as the assembler symbol name.
438 TOP_LEVEL is nonzero if this is a file-scope variable.
440 This is never called for PARM_DECL nodes. */
443 make_decl_rtl (decl, asmspec, top_level)
448 register char *name = 0;
453 bc_make_decl_rtl (decl, asmspec, top_level);
457 reg_number = decode_reg_name (asmspec);
459 if (DECL_ASSEMBLER_NAME (decl) != NULL_TREE)
460 name = IDENTIFIER_POINTER (DECL_ASSEMBLER_NAME (decl));
462 if (reg_number == -2)
464 /* ASMSPEC is given, and not the name of a register. */
465 name = (char *) obstack_alloc (saveable_obstack,
466 strlen (asmspec) + 2);
468 strcpy (&name[1], asmspec);
471 /* For a duplicate declaration, we can be called twice on the
472 same DECL node. Don't discard the RTL already made. */
473 if (DECL_RTL (decl) == 0)
477 /* First detect errors in declaring global registers. */
478 if (DECL_REGISTER (decl) && reg_number == -1)
479 error_with_decl (decl,
480 "register name not specified for `%s'");
481 else if (DECL_REGISTER (decl) && reg_number < 0)
482 error_with_decl (decl,
483 "invalid register name for `%s'");
484 else if ((reg_number >= 0 || reg_number == -3) && ! DECL_REGISTER (decl))
485 error_with_decl (decl,
486 "register name given for non-register variable `%s'");
487 else if (DECL_REGISTER (decl) && TREE_CODE (decl) == FUNCTION_DECL)
488 error ("function declared `register'");
489 else if (DECL_REGISTER (decl) && TYPE_MODE (TREE_TYPE (decl)) == BLKmode)
490 error_with_decl (decl, "data type of `%s' isn't suitable for a register");
491 else if (DECL_REGISTER (decl)
492 && ! HARD_REGNO_MODE_OK (reg_number, TYPE_MODE (TREE_TYPE (decl))))
493 error_with_decl (decl, "register number for `%s' isn't suitable for the data type");
494 /* Now handle properly declared static register variables. */
495 else if (DECL_REGISTER (decl))
498 #if 0 /* yylex should print the warning for this */
500 pedwarn ("ANSI C forbids global register variables");
502 if (DECL_INITIAL (decl) != 0 && top_level)
504 DECL_INITIAL (decl) = 0;
505 error ("global register variable has initial value");
507 if (fixed_regs[reg_number] == 0
508 && function_defined && top_level)
509 error ("global register variable follows a function definition");
510 if (TREE_THIS_VOLATILE (decl))
511 warning ("volatile register variables don't work as you might wish");
513 /* If the user specified one of the eliminables registers here,
514 e.g., FRAME_POINTER_REGNUM, we don't want to get this variable
515 confused with that register and be eliminated. Although this
516 usage is somewhat suspect, we nevertheless use the following
517 kludge to avoid setting DECL_RTL to frame_pointer_rtx. */
520 = gen_rtx (REG, DECL_MODE (decl), FIRST_PSEUDO_REGISTER);
521 REGNO (DECL_RTL (decl)) = reg_number;
522 REG_USERVAR_P (DECL_RTL (decl)) = 1;
526 /* Make this register global, so not usable for anything
528 nregs = HARD_REGNO_NREGS (reg_number, DECL_MODE (decl));
530 globalize_reg (reg_number + --nregs);
533 /* Specifying a section attribute on an uninitialized variable does not
534 (and cannot) cause it to be put in the given section. The linker
535 can only put initialized objects in specific sections, everything
536 else goes in bss for the linker to sort out later (otherwise the
537 linker would give a duplicate definition error for each compilation
538 unit that behaved thusly). So warn the user. */
539 else if (TREE_CODE (decl) == VAR_DECL
540 && DECL_SECTION_NAME (decl) != NULL_TREE
541 && DECL_INITIAL (decl) == NULL_TREE
542 && DECL_COMMON (decl)
545 warning_with_decl (decl,
546 "section attribute ignored for uninitialized variable `%s'");
547 /* Remove the section name so subsequent declarations won't see it.
548 We are ignoring it, remember. */
549 DECL_SECTION_NAME (decl) = NULL_TREE;
552 /* Now handle ordinary static variables and functions (in memory).
553 Also handle vars declared register invalidly. */
554 if (DECL_RTL (decl) == 0)
556 /* Can't use just the variable's own name for a variable
557 whose scope is less than the whole file.
558 Concatenate a distinguishing number. */
559 if (!top_level && !DECL_EXTERNAL (decl) && asmspec == 0)
563 ASM_FORMAT_PRIVATE_NAME (label, name, var_labelno);
564 name = obstack_copy0 (saveable_obstack, label, strlen (label));
571 DECL_RTL (decl) = gen_rtx (MEM, DECL_MODE (decl),
572 gen_rtx (SYMBOL_REF, Pmode, name));
574 /* If this variable is to be treated as volatile, show its
575 tree node has side effects. If it has side effects, either
576 because of this test or from TREE_THIS_VOLATILE also
577 being set, show the MEM is volatile. */
578 if (flag_volatile_global && TREE_CODE (decl) == VAR_DECL
579 && TREE_PUBLIC (decl))
580 TREE_SIDE_EFFECTS (decl) = 1;
581 if (TREE_SIDE_EFFECTS (decl))
582 MEM_VOLATILE_P (DECL_RTL (decl)) = 1;
584 if (TREE_READONLY (decl))
585 RTX_UNCHANGING_P (DECL_RTL (decl)) = 1;
586 MEM_IN_STRUCT_P (DECL_RTL (decl))
587 = AGGREGATE_TYPE_P (TREE_TYPE (decl));
589 /* Optionally set flags or add text to the name to record information
590 such as that it is a function name.
591 If the name is changed, the macro ASM_OUTPUT_LABELREF
592 will have to know how to strip this information. */
593 #ifdef ENCODE_SECTION_INFO
594 ENCODE_SECTION_INFO (decl);
598 /* If the old RTL had the wrong mode, fix the mode. */
599 else if (GET_MODE (DECL_RTL (decl)) != DECL_MODE (decl))
601 rtx rtl = DECL_RTL (decl);
602 PUT_MODE (rtl, DECL_MODE (decl));
606 /* Make the rtl for variable VAR be volatile.
607 Use this only for static variables. */
610 make_var_volatile (var)
613 if (GET_CODE (DECL_RTL (var)) != MEM)
616 MEM_VOLATILE_P (DECL_RTL (var)) = 1;
619 /* Output alignment directive to align for constant expression EXP. */
622 assemble_constant_align (exp)
627 /* Align the location counter as required by EXP's data type. */
628 align = TYPE_ALIGN (TREE_TYPE (exp));
629 #ifdef CONSTANT_ALIGNMENT
630 align = CONSTANT_ALIGNMENT (exp, align);
633 if (align > BITS_PER_UNIT)
634 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
637 /* Output a string of literal assembler code
638 for an `asm' keyword used between functions. */
641 assemble_asm (string)
646 error ("asm statements not allowed in interpreter");
652 if (TREE_CODE (string) == ADDR_EXPR)
653 string = TREE_OPERAND (string, 0);
655 fprintf (asm_out_file, "\t%s\n", TREE_STRING_POINTER (string));
658 #if 0 /* This should no longer be needed, because
659 flag_gnu_linker should be 0 on these systems,
660 which should prevent any output
661 if ASM_OUTPUT_CONSTRUCTOR and ASM_OUTPUT_DESTRUCTOR are absent. */
662 #if !(defined(DBX_DEBUGGING_INFO) && !defined(FASCIST_ASSEMBLER))
663 #ifndef ASM_OUTPUT_CONSTRUCTOR
664 #define ASM_OUTPUT_CONSTRUCTOR(file, name)
666 #ifndef ASM_OUTPUT_DESTRUCTOR
667 #define ASM_OUTPUT_DESTRUCTOR(file, name)
672 /* Record an element in the table of global destructors.
673 How this is done depends on what sort of assembler and linker
676 NAME should be the name of a global function to be called
677 at exit time. This name is output using assemble_name. */
680 assemble_destructor (name)
683 #ifdef ASM_OUTPUT_DESTRUCTOR
684 ASM_OUTPUT_DESTRUCTOR (asm_out_file, name);
688 /* Now tell GNU LD that this is part of the static destructor set. */
689 /* This code works for any machine provided you use GNU as/ld. */
690 fprintf (asm_out_file, "%s \"___DTOR_LIST__\",22,0,0,", ASM_STABS_OP);
691 assemble_name (asm_out_file, name);
692 fputc ('\n', asm_out_file);
697 /* Likewise for global constructors. */
700 assemble_constructor (name)
703 #ifdef ASM_OUTPUT_CONSTRUCTOR
704 ASM_OUTPUT_CONSTRUCTOR (asm_out_file, name);
708 /* Now tell GNU LD that this is part of the static constructor set. */
709 /* This code works for any machine provided you use GNU as/ld. */
710 fprintf (asm_out_file, "%s \"___CTOR_LIST__\",22,0,0,", ASM_STABS_OP);
711 assemble_name (asm_out_file, name);
712 fputc ('\n', asm_out_file);
717 /* Likewise for entries we want to record for garbage collection.
718 Garbage collection is still under development. */
721 assemble_gc_entry (name)
724 #ifdef ASM_OUTPUT_GC_ENTRY
725 ASM_OUTPUT_GC_ENTRY (asm_out_file, name);
729 /* Now tell GNU LD that this is part of the static constructor set. */
730 fprintf (asm_out_file, "%s \"___PTR_LIST__\",22,0,0,", ASM_STABS_OP);
731 assemble_name (asm_out_file, name);
732 fputc ('\n', asm_out_file);
737 /* Output assembler code for the constant pool of a function and associated
738 with defining the name of the function. DECL describes the function.
739 NAME is the function's name. For the constant pool, we use the current
740 constant pool data. */
743 assemble_start_function (decl, fnname)
749 /* The following code does not need preprocessing in the assembler. */
753 output_constant_pool (fnname, decl);
755 function_section (decl);
757 /* Tell assembler to move to target machine's alignment for functions. */
758 align = floor_log2 (FUNCTION_BOUNDARY / BITS_PER_UNIT);
762 BC_OUTPUT_ALIGN (asm_out_file, align);
764 ASM_OUTPUT_ALIGN (asm_out_file, align);
767 #ifdef ASM_OUTPUT_FUNCTION_PREFIX
768 ASM_OUTPUT_FUNCTION_PREFIX (asm_out_file, fnname);
771 #ifdef SDB_DEBUGGING_INFO
772 /* Output SDB definition of the function. */
773 if (write_symbols == SDB_DEBUG)
774 sdbout_mark_begin_function ();
777 #ifdef DBX_DEBUGGING_INFO
778 /* Output DBX definition of the function. */
779 if (write_symbols == DBX_DEBUG)
780 dbxout_begin_function (decl);
783 /* Make function name accessible from other files, if appropriate. */
785 if (TREE_PUBLIC (decl))
787 if (!first_global_object_name)
788 STRIP_NAME_ENCODING (first_global_object_name, fnname);
790 BC_GLOBALIZE_LABEL (asm_out_file, fnname);
792 ASM_GLOBALIZE_LABEL (asm_out_file, fnname);
795 /* Do any machine/system dependent processing of the function name */
796 #ifdef ASM_DECLARE_FUNCTION_NAME
797 ASM_DECLARE_FUNCTION_NAME (asm_out_file, fnname, current_function_decl);
799 /* Standard thing is just output label for the function. */
801 BC_OUTPUT_LABEL (asm_out_file, fnname);
803 ASM_OUTPUT_LABEL (asm_out_file, fnname);
804 #endif /* ASM_DECLARE_FUNCTION_NAME */
807 /* Output assembler code associated with defining the size of the
808 function. DECL describes the function. NAME is the function's name. */
811 assemble_end_function (decl, fnname)
815 #ifdef ASM_DECLARE_FUNCTION_SIZE
816 ASM_DECLARE_FUNCTION_SIZE (asm_out_file, fnname, decl);
820 /* Assemble code to leave SIZE bytes of zeros. */
823 assemble_zeros (size)
828 bc_emit_const_skip (size);
832 #ifdef ASM_NO_SKIP_IN_TEXT
833 /* The `space' pseudo in the text section outputs nop insns rather than 0s,
834 so we must output 0s explicitly in the text section. */
835 if (ASM_NO_SKIP_IN_TEXT && in_text_section ())
839 for (i = 0; i < size - 20; i += 20)
842 fprintf (asm_out_file,
843 "%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);
845 fprintf (asm_out_file,
846 "\tbyte 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0\n");
852 fprintf (asm_out_file, "%s 0", ASM_BYTE_OP);
854 fprintf (asm_out_file, "\tbyte 0");
857 for (; i < size; i++)
858 fprintf (asm_out_file, ",0");
859 fprintf (asm_out_file, "\n");
867 BC_OUTPUT_SKIP (asm_out_file, size);
869 ASM_OUTPUT_SKIP (asm_out_file, size);
873 /* Assemble an alignment pseudo op for an ALIGN-bit boundary. */
876 assemble_align (align)
879 if (align > BITS_PER_UNIT)
880 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
883 /* Assemble a string constant with the specified C string as contents. */
886 assemble_string (p, size)
900 /* If the string is very long, split it up. */
904 int thissize = size - pos;
905 if (thissize > maximum)
909 bc_output_ascii (asm_out_file, p, thissize);
912 ASM_OUTPUT_ASCII (asm_out_file, p, thissize);
921 bc_output_ascii (file, p, size)
926 BC_OUTPUT_ASCII (file, p, size);
929 /* Assemble everything that is needed for a variable or function declaration.
930 Not used for automatic variables, and not used for function definitions.
931 Should not be called for variables of incomplete structure type.
933 TOP_LEVEL is nonzero if this variable has file scope.
934 AT_END is nonzero if this is the special handling, at end of compilation,
935 to define things that have had only tentative definitions.
936 DONT_OUTPUT_DATA if nonzero means don't actually output the
937 initial value (that will be done by the caller). */
940 assemble_variable (decl, top_level, at_end, dont_output_data)
944 int dont_output_data;
950 enum in_section saved_in_section;
952 last_assemble_variable_decl = 0;
957 if (GET_CODE (DECL_RTL (decl)) == REG)
959 /* Do output symbol info for global register variables, but do nothing
962 if (TREE_ASM_WRITTEN (decl))
964 TREE_ASM_WRITTEN (decl) = 1;
966 if (!output_bytecode)
968 #if defined (DBX_DEBUGGING_INFO) || defined (XCOFF_DEBUGGING_INFO)
969 /* File-scope global variables are output here. */
970 if ((write_symbols == DBX_DEBUG || write_symbols == XCOFF_DEBUG)
972 dbxout_symbol (decl, 0);
974 #ifdef SDB_DEBUGGING_INFO
975 if (write_symbols == SDB_DEBUG && top_level
976 /* Leave initialized global vars for end of compilation;
977 see comment in compile_file. */
978 && (TREE_PUBLIC (decl) == 0 || DECL_INITIAL (decl) == 0))
979 sdbout_symbol (decl, 0);
983 /* Don't output any DWARF debugging information for variables here.
984 In the case of local variables, the information for them is output
985 when we do our recursive traversal of the tree representation for
986 the entire containing function. In the case of file-scope variables,
987 we output information for all of them at the very end of compilation
988 while we are doing our final traversal of the chain of file-scope
994 /* Normally no need to say anything here for external references,
995 since assemble_external is called by the langauge-specific code
996 when a declaration is first seen. */
998 if (DECL_EXTERNAL (decl))
1001 /* Output no assembler code for a function declaration.
1002 Only definitions of functions output anything. */
1004 if (TREE_CODE (decl) == FUNCTION_DECL)
1007 /* If type was incomplete when the variable was declared,
1008 see if it is complete now. */
1010 if (DECL_SIZE (decl) == 0)
1011 layout_decl (decl, 0);
1013 /* Still incomplete => don't allocate it; treat the tentative defn
1014 (which is what it must have been) as an `extern' reference. */
1016 if (!dont_output_data && DECL_SIZE (decl) == 0)
1018 error_with_file_and_line (DECL_SOURCE_FILE (decl),
1019 DECL_SOURCE_LINE (decl),
1020 "storage size of `%s' isn't known",
1021 IDENTIFIER_POINTER (DECL_NAME (decl)));
1022 TREE_ASM_WRITTEN (decl) = 1;
1026 /* The first declaration of a variable that comes through this function
1027 decides whether it is global (in C, has external linkage)
1028 or local (in C, has internal linkage). So do nothing more
1029 if this function has already run. */
1031 if (TREE_ASM_WRITTEN (decl))
1034 TREE_ASM_WRITTEN (decl) = 1;
1038 if (! dont_output_data)
1040 if (TREE_CODE (DECL_SIZE (decl)) != INTEGER_CST)
1043 /* This is better than explicit arithmetic, since it avoids overflow. */
1044 size_tree = size_binop (CEIL_DIV_EXPR,
1045 DECL_SIZE (decl), size_int (BITS_PER_UNIT));
1047 if (TREE_INT_CST_HIGH (size_tree) != 0)
1049 error_with_decl (decl, "size of variable `%s' is too large");
1054 name = XSTR (XEXP (DECL_RTL (decl), 0), 0);
1056 /* Handle uninitialized definitions. */
1058 /* ANSI specifies that a tentative definition which is not merged with
1059 a non-tentative definition behaves exactly like a definition with an
1060 initializer equal to zero. (Section 3.7.2)
1061 -fno-common gives strict ANSI behavior. Usually you don't want it.
1062 This matters only for variables with external linkage. */
1063 if ((! flag_no_common || ! TREE_PUBLIC (decl))
1064 && DECL_COMMON (decl)
1065 && ! dont_output_data
1066 && (DECL_INITIAL (decl) == 0 || DECL_INITIAL (decl) == error_mark_node))
1068 int size = TREE_INT_CST_LOW (size_tree);
1071 if (TREE_INT_CST_HIGH (size_tree) != 0)
1072 error_with_decl (decl, "size of variable `%s' is too large");
1073 /* Don't allocate zero bytes of common,
1074 since that means "undefined external" in the linker. */
1075 if (size == 0) rounded = 1;
1076 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1077 so that each uninitialized object starts on such a boundary. */
1078 rounded += (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1;
1079 rounded = (rounded / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1080 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1082 #ifdef DBX_DEBUGGING_INFO
1083 /* File-scope global variables are output here. */
1084 if (write_symbols == DBX_DEBUG && top_level)
1085 dbxout_symbol (decl, 0);
1087 #ifdef SDB_DEBUGGING_INFO
1088 if (write_symbols == SDB_DEBUG && top_level
1089 /* Leave initialized global vars for end of compilation;
1090 see comment in compile_file. */
1091 && (TREE_PUBLIC (decl) == 0 || DECL_INITIAL (decl) == 0))
1092 sdbout_symbol (decl, 0);
1095 /* Don't output any DWARF debugging information for variables here.
1096 In the case of local variables, the information for them is output
1097 when we do our recursive traversal of the tree representation for
1098 the entire containing function. In the case of file-scope variables,
1099 we output information for all of them at the very end of compilation
1100 while we are doing our final traversal of the chain of file-scope
1104 if (flag_shared_data)
1107 if (TREE_PUBLIC (decl))
1109 #ifdef ASM_OUTPUT_SHARED_COMMON
1110 if (flag_shared_data)
1111 ASM_OUTPUT_SHARED_COMMON (asm_out_file, name, size, rounded);
1114 if (output_bytecode)
1116 BC_OUTPUT_COMMON (asm_out_file, name, size, rounded);
1120 #ifdef ASM_OUTPUT_ALIGNED_COMMON
1121 ASM_OUTPUT_ALIGNED_COMMON (asm_out_file, name, size,
1124 ASM_OUTPUT_COMMON (asm_out_file, name, size, rounded);
1130 #ifdef ASM_OUTPUT_SHARED_LOCAL
1131 if (flag_shared_data)
1132 ASM_OUTPUT_SHARED_LOCAL (asm_out_file, name, size, rounded);
1135 if (output_bytecode)
1137 BC_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1141 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
1142 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size,
1145 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1152 /* Handle initialized definitions. */
1154 /* First make the assembler name(s) global if appropriate. */
1155 if (TREE_PUBLIC (decl) && DECL_NAME (decl))
1157 if (!first_global_object_name)
1158 STRIP_NAME_ENCODING(first_global_object_name, name);
1159 ASM_GLOBALIZE_LABEL (asm_out_file, name);
1162 for (d = equivalents; d; d = TREE_CHAIN (d))
1164 tree e = TREE_VALUE (d);
1165 if (TREE_PUBLIC (e) && DECL_NAME (e))
1166 ASM_GLOBALIZE_LABEL (asm_out_file,
1167 XSTR (XEXP (DECL_RTL (e), 0), 0));
1171 /* Output any data that we will need to use the address of. */
1172 if (DECL_INITIAL (decl) == error_mark_node)
1173 reloc = contains_pointers_p (TREE_TYPE (decl));
1174 else if (DECL_INITIAL (decl))
1175 reloc = output_addressed_constants (DECL_INITIAL (decl));
1177 /* Switch to the proper section for this data. */
1178 if (IN_NAMED_SECTION (decl))
1179 named_section (decl, NULL);
1182 /* C++ can have const variables that get initialized from constructors,
1183 and thus can not be in a readonly section. We prevent this by
1184 verifying that the initial value is constant for objects put in a
1187 error_mark_node is used by the C front end to indicate that the
1188 initializer has not been seen yet. In this case, we assume that
1189 the initializer must be constant. */
1190 #ifdef SELECT_SECTION
1191 SELECT_SECTION (decl, reloc);
1193 if (TREE_READONLY (decl)
1194 && ! TREE_THIS_VOLATILE (decl)
1195 && DECL_INITIAL (decl)
1196 && (DECL_INITIAL (decl) == error_mark_node
1197 || TREE_CONSTANT (DECL_INITIAL (decl)))
1198 && ! (flag_pic && reloc))
1199 readonly_data_section ();
1205 /* dbxout.c needs to know this. */
1206 if (in_text_section ())
1207 DECL_IN_TEXT_SECTION (decl) = 1;
1209 /* Record current section so we can restore it if dbxout.c clobbers it. */
1210 saved_in_section = in_section;
1212 /* Output the dbx info now that we have chosen the section. */
1214 #ifdef DBX_DEBUGGING_INFO
1215 /* File-scope global variables are output here. */
1216 if (write_symbols == DBX_DEBUG && top_level)
1217 dbxout_symbol (decl, 0);
1219 #ifdef SDB_DEBUGGING_INFO
1220 if (write_symbols == SDB_DEBUG && top_level
1221 /* Leave initialized global vars for end of compilation;
1222 see comment in compile_file. */
1223 && (TREE_PUBLIC (decl) == 0 || DECL_INITIAL (decl) == 0))
1224 sdbout_symbol (decl, 0);
1227 /* Don't output any DWARF debugging information for variables here.
1228 In the case of local variables, the information for them is output
1229 when we do our recursive traversal of the tree representation for
1230 the entire containing function. In the case of file-scope variables,
1231 we output information for all of them at the very end of compilation
1232 while we are doing our final traversal of the chain of file-scope
1235 /* If the debugging output changed sections, reselect the section
1236 that's supposed to be selected. */
1237 if (in_section != saved_in_section)
1239 /* Switch to the proper section for this data. */
1240 #ifdef SELECT_SECTION
1241 SELECT_SECTION (decl, reloc);
1243 if (TREE_READONLY (decl)
1244 && ! TREE_THIS_VOLATILE (decl)
1245 && DECL_INITIAL (decl)
1246 && (DECL_INITIAL (decl) == error_mark_node
1247 || TREE_CONSTANT (DECL_INITIAL (decl)))
1248 && ! (flag_pic && reloc))
1249 readonly_data_section ();
1255 /* Compute and output the alignment of this data. */
1257 align = DECL_ALIGN (decl);
1258 /* In the case for initialing an array whose length isn't specified,
1259 where we have not yet been able to do the layout,
1260 figure out the proper alignment now. */
1261 if (dont_output_data && DECL_SIZE (decl) == 0
1262 && TREE_CODE (TREE_TYPE (decl)) == ARRAY_TYPE)
1263 align = MAX (align, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))));
1265 /* Some object file formats have a maximum alignment which they support.
1266 In particular, a.out format supports a maximum alignment of 4. */
1267 #ifndef MAX_OFILE_ALIGNMENT
1268 #define MAX_OFILE_ALIGNMENT BIGGEST_ALIGNMENT
1270 if (align > MAX_OFILE_ALIGNMENT)
1272 warning_with_decl (decl,
1273 "alignment of `%s' is greater than maximum object file alignment");
1274 align = MAX_OFILE_ALIGNMENT;
1276 #ifdef DATA_ALIGNMENT
1277 /* On some machines, it is good to increase alignment sometimes. */
1278 align = DATA_ALIGNMENT (TREE_TYPE (decl), align);
1280 #ifdef CONSTANT_ALIGNMENT
1281 if (DECL_INITIAL (decl))
1282 align = CONSTANT_ALIGNMENT (DECL_INITIAL (decl), align);
1285 /* Reset the alignment in case we have made it tighter, so we can benefit
1286 from it in get_pointer_alignment. */
1287 DECL_ALIGN (decl) = align;
1289 if (align > BITS_PER_UNIT)
1291 if (output_bytecode)
1292 BC_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1294 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
1297 /* Do any machine/system dependent processing of the object. */
1298 #ifdef ASM_DECLARE_OBJECT_NAME
1299 last_assemble_variable_decl = decl;
1300 ASM_DECLARE_OBJECT_NAME (asm_out_file, name, decl);
1302 /* Standard thing is just output label for the object. */
1303 if (output_bytecode)
1304 BC_OUTPUT_LABEL (asm_out_file, name);
1306 ASM_OUTPUT_LABEL (asm_out_file, name);
1307 #endif /* ASM_DECLARE_OBJECT_NAME */
1309 if (!dont_output_data)
1311 if (DECL_INITIAL (decl))
1312 /* Output the actual data. */
1313 output_constant (DECL_INITIAL (decl), TREE_INT_CST_LOW (size_tree));
1315 /* Leave space for it. */
1316 assemble_zeros (TREE_INT_CST_LOW (size_tree));
1320 #ifdef XCOFF_DEBUGGING_INFO
1321 /* Unfortunately, the IBM assembler cannot handle stabx before the actual
1322 declaration. When something like ".stabx "aa:S-2",aa,133,0" is emitted
1323 and `aa' hasn't been output yet, the assembler generates a stab entry with
1324 a value of zero, in addition to creating an unnecessary external entry
1325 for `aa'. Hence, we must postpone dbxout_symbol to here at the end. */
1327 /* File-scope global variables are output here. */
1328 if (write_symbols == XCOFF_DEBUG && top_level)
1330 saved_in_section = in_section;
1332 dbxout_symbol (decl, 0);
1334 if (in_section != saved_in_section)
1336 /* Switch to the proper section for this data. */
1337 #ifdef SELECT_SECTION
1338 SELECT_SECTION (decl, reloc);
1340 if (TREE_READONLY (decl)
1341 && ! TREE_THIS_VOLATILE (decl)
1342 && DECL_INITIAL (decl)
1343 && (DECL_INITIAL (decl) == error_mark_node
1344 || TREE_CONSTANT (DECL_INITIAL (decl)))
1345 && ! (flag_pic && reloc))
1346 readonly_data_section ();
1353 /* There must be a statement after a label. */
1358 /* Return 1 if type TYPE contains any pointers. */
1361 contains_pointers_p (type)
1364 switch (TREE_CODE (type))
1367 case REFERENCE_TYPE:
1368 /* I'm not sure whether OFFSET_TYPE needs this treatment,
1369 so I'll play safe and return 1. */
1375 case QUAL_UNION_TYPE:
1378 /* For a type that has fields, see if the fields have pointers. */
1379 for (fields = TYPE_FIELDS (type); fields; fields = TREE_CHAIN (fields))
1380 if (TREE_CODE (fields) == FIELD_DECL
1381 && contains_pointers_p (TREE_TYPE (fields)))
1387 /* An array type contains pointers if its element type does. */
1388 return contains_pointers_p (TREE_TYPE (type));
1395 /* Output text storage for constructor CONSTR. */
1398 bc_output_constructor (constr, size)
1404 /* Must always be a literal; non-literal constructors are handled
1407 if (!TREE_CONSTANT (constr))
1414 for (i = 0; TYPE_ALIGN (constr) >= BITS_PER_UNIT << (i + 1); i++)
1418 BC_OUTPUT_ALIGN (asm_out_file, i);
1421 output_constant (constr, size);
1424 /* Create storage for constructor CONSTR. */
1427 bc_output_data_constructor (constr)
1432 /* Put in data section */
1436 for (i = 0; TYPE_ALIGN (constr) >= BITS_PER_UNIT << (i + 1); i++);
1438 BC_OUTPUT_ALIGN (asm_out_file, i);
1440 /* The constructor is filled in at runtime. */
1441 BC_OUTPUT_SKIP (asm_out_file, int_size_in_bytes (TREE_TYPE (constr)));
1444 /* Output something to declare an external symbol to the assembler.
1445 (Most assemblers don't need this, so we normally output nothing.)
1446 Do nothing if DECL is not external. */
1449 assemble_external (decl)
1452 if (output_bytecode)
1455 #ifdef ASM_OUTPUT_EXTERNAL
1456 if (TREE_CODE_CLASS (TREE_CODE (decl)) == 'd'
1457 && DECL_EXTERNAL (decl) && TREE_PUBLIC (decl))
1459 rtx rtl = DECL_RTL (decl);
1461 if (GET_CODE (rtl) == MEM && GET_CODE (XEXP (rtl, 0)) == SYMBOL_REF
1462 && ! SYMBOL_REF_USED (XEXP (rtl, 0)))
1464 /* Some systems do require some output. */
1465 SYMBOL_REF_USED (XEXP (rtl, 0)) = 1;
1466 ASM_OUTPUT_EXTERNAL (asm_out_file, decl, XSTR (XEXP (rtl, 0), 0));
1472 /* Similar, for calling a library function FUN. */
1475 assemble_external_libcall (fun)
1478 #ifdef ASM_OUTPUT_EXTERNAL_LIBCALL
1479 if (!output_bytecode)
1481 /* Declare library function name external when first used, if nec. */
1482 if (! SYMBOL_REF_USED (fun))
1484 SYMBOL_REF_USED (fun) = 1;
1485 ASM_OUTPUT_EXTERNAL_LIBCALL (asm_out_file, fun);
1491 /* Declare the label NAME global. */
1494 assemble_global (name)
1497 ASM_GLOBALIZE_LABEL (asm_out_file, name);
1500 /* Assemble a label named NAME. */
1503 assemble_label (name)
1506 if (output_bytecode)
1507 BC_OUTPUT_LABEL (asm_out_file, name);
1509 ASM_OUTPUT_LABEL (asm_out_file, name);
1512 /* Output to FILE a reference to the assembler name of a C-level name NAME.
1513 If NAME starts with a *, the rest of NAME is output verbatim.
1514 Otherwise NAME is transformed in an implementation-defined way
1515 (usually by the addition of an underscore).
1516 Many macros in the tm file are defined to call this function. */
1519 assemble_name (file, name)
1525 STRIP_NAME_ENCODING (real_name, name);
1526 TREE_SYMBOL_REFERENCED (get_identifier (real_name)) = 1;
1530 if (output_bytecode)
1531 bc_emit_labelref (name);
1533 fputs (&name[1], file);
1537 if (output_bytecode)
1538 BC_OUTPUT_LABELREF (file, name);
1540 ASM_OUTPUT_LABELREF (file, name);
1544 /* Allocate SIZE bytes writable static space with a gensym name
1545 and return an RTX to refer to its address. */
1548 assemble_static_space (size)
1554 /* Round size up to multiple of BIGGEST_ALIGNMENT bits
1555 so that each uninitialized object starts on such a boundary. */
1556 int rounded = ((size + (BIGGEST_ALIGNMENT / BITS_PER_UNIT) - 1)
1557 / (BIGGEST_ALIGNMENT / BITS_PER_UNIT)
1558 * (BIGGEST_ALIGNMENT / BITS_PER_UNIT));
1561 if (flag_shared_data)
1565 ASM_GENERATE_INTERNAL_LABEL (name, "LF", const_labelno);
1568 namestring = (char *) obstack_alloc (saveable_obstack,
1570 strcpy (namestring, name);
1572 if (output_bytecode)
1573 x = bc_gen_rtx (namestring, 0, (struct bc_label *) 0);
1575 x = gen_rtx (SYMBOL_REF, Pmode, namestring);
1577 if (output_bytecode)
1579 BC_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1583 #ifdef ASM_OUTPUT_ALIGNED_LOCAL
1584 ASM_OUTPUT_ALIGNED_LOCAL (asm_out_file, name, size, BIGGEST_ALIGNMENT);
1586 ASM_OUTPUT_LOCAL (asm_out_file, name, size, rounded);
1592 /* Assemble the static constant template for function entry trampolines.
1593 This is done at most once per compilation.
1594 Returns an RTX for the address of the template. */
1597 assemble_trampoline_template ()
1603 /* Shouldn't get here */
1604 if (output_bytecode)
1607 /* By default, put trampoline templates in read-only data section. */
1609 #ifdef TRAMPOLINE_SECTION
1610 TRAMPOLINE_SECTION ();
1612 readonly_data_section ();
1615 /* Write the assembler code to define one. */
1616 align = floor_log2 (FUNCTION_BOUNDARY / BITS_PER_UNIT);
1618 ASM_OUTPUT_ALIGN (asm_out_file, align);
1620 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LTRAMP", 0);
1621 TRAMPOLINE_TEMPLATE (asm_out_file);
1623 /* Record the rtl to refer to it. */
1624 ASM_GENERATE_INTERNAL_LABEL (label, "LTRAMP", 0);
1626 = (char *) obstack_copy0 (&permanent_obstack, label, strlen (label));
1627 return gen_rtx (SYMBOL_REF, Pmode, name);
1630 /* Assemble the integer constant X into an object of SIZE bytes.
1631 X must be either a CONST_INT or CONST_DOUBLE.
1633 Return 1 if we were able to output the constant, otherwise 0. If FORCE is
1634 non-zero, abort if we can't output the constant. */
1637 assemble_integer (x, size, force)
1642 /* First try to use the standard 1, 2, 4, 8, and 16 byte
1643 ASM_OUTPUT... macros. */
1647 #ifdef ASM_OUTPUT_CHAR
1649 ASM_OUTPUT_CHAR (asm_out_file, x);
1653 #ifdef ASM_OUTPUT_SHORT
1655 ASM_OUTPUT_SHORT (asm_out_file, x);
1659 #ifdef ASM_OUTPUT_INT
1661 ASM_OUTPUT_INT (asm_out_file, x);
1665 #ifdef ASM_OUTPUT_DOUBLE_INT
1667 ASM_OUTPUT_DOUBLE_INT (asm_out_file, x);
1671 #ifdef ASM_OUTPUT_QUADRUPLE_INT
1673 ASM_OUTPUT_QUADRUPLE_INT (asm_out_file, x);
1678 /* If we couldn't do it that way, there are two other possibilities: First,
1679 if the machine can output an explicit byte and this is a 1 byte constant,
1680 we can use ASM_OUTPUT_BYTE. */
1682 #ifdef ASM_OUTPUT_BYTE
1683 if (size == 1 && GET_CODE (x) == CONST_INT)
1685 ASM_OUTPUT_BYTE (asm_out_file, INTVAL (x));
1690 /* Finally, if SIZE is larger than a single word, try to output the constant
1691 one word at a time. */
1693 if (size > UNITS_PER_WORD)
1696 enum machine_mode mode
1697 = mode_for_size (size * BITS_PER_UNIT, MODE_INT, 0);
1700 for (i = 0; i < size / UNITS_PER_WORD; i++)
1702 word = operand_subword (x, i, 0, mode);
1707 if (! assemble_integer (word, UNITS_PER_WORD, 0))
1711 if (i == size / UNITS_PER_WORD)
1713 /* If we output at least one word and then could not finish,
1714 there is no valid way to continue. */
1725 /* Assemble the floating-point constant D into an object of size MODE. */
1728 assemble_real (d, mode)
1730 enum machine_mode mode;
1732 jmp_buf output_constant_handler;
1734 if (setjmp (output_constant_handler))
1736 error ("floating point trap outputting a constant");
1737 #ifdef REAL_IS_NOT_DOUBLE
1738 bzero ((char *) &d, sizeof d);
1745 set_float_handler (output_constant_handler);
1749 #ifdef ASM_OUTPUT_BYTE_FLOAT
1751 ASM_OUTPUT_BYTE_FLOAT (asm_out_file, d);
1754 #ifdef ASM_OUTPUT_SHORT_FLOAT
1756 ASM_OUTPUT_SHORT_FLOAT (asm_out_file, d);
1759 #ifdef ASM_OUTPUT_THREE_QUARTER_FLOAT
1761 ASM_OUTPUT_THREE_QUARTER_FLOAT (asm_out_file, d);
1764 #ifdef ASM_OUTPUT_FLOAT
1766 ASM_OUTPUT_FLOAT (asm_out_file, d);
1770 #ifdef ASM_OUTPUT_DOUBLE
1772 ASM_OUTPUT_DOUBLE (asm_out_file, d);
1776 #ifdef ASM_OUTPUT_LONG_DOUBLE
1779 ASM_OUTPUT_LONG_DOUBLE (asm_out_file, d);
1787 set_float_handler (NULL_PTR);
1790 /* Here we combine duplicate floating constants to make
1791 CONST_DOUBLE rtx's, and force those out to memory when necessary. */
1793 /* Chain of all CONST_DOUBLE rtx's constructed for the current function.
1794 They are chained through the CONST_DOUBLE_CHAIN.
1795 A CONST_DOUBLE rtx has CONST_DOUBLE_MEM != cc0_rtx iff it is on this chain.
1796 In that case, CONST_DOUBLE_MEM is either a MEM,
1797 or const0_rtx if no MEM has been made for this CONST_DOUBLE yet.
1799 (CONST_DOUBLE_MEM is used only for top-level functions.
1800 See force_const_mem for explanation.) */
1802 static rtx const_double_chain;
1804 /* Return a CONST_DOUBLE or CONST_INT for a value specified as a pair of ints.
1805 For an integer, I0 is the low-order word and I1 is the high-order word.
1806 For a real number, I0 is the word with the low address
1807 and I1 is the word with the high address. */
1810 immed_double_const (i0, i1, mode)
1811 HOST_WIDE_INT i0, i1;
1812 enum machine_mode mode;
1815 int in_current_obstack;
1817 if (GET_MODE_CLASS (mode) == MODE_INT
1818 || GET_MODE_CLASS (mode) == MODE_PARTIAL_INT)
1820 /* We clear out all bits that don't belong in MODE, unless they and our
1821 sign bit are all one. So we get either a reasonable negative value
1822 or a reasonable unsigned value for this mode. */
1823 int width = GET_MODE_BITSIZE (mode);
1824 if (width < HOST_BITS_PER_WIDE_INT
1825 && ((i0 & ((HOST_WIDE_INT) (-1) << (width - 1)))
1826 != ((HOST_WIDE_INT) (-1) << (width - 1))))
1827 i0 &= ((HOST_WIDE_INT) 1 << width) - 1, i1 = 0;
1828 else if (width == HOST_BITS_PER_WIDE_INT
1829 && ! (i1 == ~0 && i0 < 0))
1831 else if (width > 2 * HOST_BITS_PER_WIDE_INT)
1832 /* We cannot represent this value as a constant. */
1835 /* If this would be an entire word for the target, but is not for
1836 the host, then sign-extend on the host so that the number will look
1837 the same way on the host that it would on the target.
1839 For example, when building a 64 bit alpha hosted 32 bit sparc
1840 targeted compiler, then we want the 32 bit unsigned value -1 to be
1841 represented as a 64 bit value -1, and not as 0x00000000ffffffff.
1842 The later confuses the sparc backend. */
1844 if (BITS_PER_WORD < HOST_BITS_PER_WIDE_INT && BITS_PER_WORD == width
1845 && (i0 & ((HOST_WIDE_INT) 1 << (width - 1))))
1846 i0 |= ((HOST_WIDE_INT) (-1) << width);
1848 /* If MODE fits within HOST_BITS_PER_WIDE_INT, always use a CONST_INT.
1850 ??? Strictly speaking, this is wrong if we create a CONST_INT
1851 for a large unsigned constant with the size of MODE being
1852 HOST_BITS_PER_WIDE_INT and later try to interpret that constant in a
1853 wider mode. In that case we will mis-interpret it as a negative
1856 Unfortunately, the only alternative is to make a CONST_DOUBLE
1857 for any constant in any mode if it is an unsigned constant larger
1858 than the maximum signed integer in an int on the host. However,
1859 doing this will break everyone that always expects to see a CONST_INT
1860 for SImode and smaller.
1862 We have always been making CONST_INTs in this case, so nothing new
1865 if (width <= HOST_BITS_PER_WIDE_INT)
1866 i1 = (i0 < 0) ? ~0 : 0;
1868 /* If this integer fits in one word, return a CONST_INT. */
1869 if ((i1 == 0 && i0 >= 0)
1870 || (i1 == ~0 && i0 < 0))
1871 return GEN_INT (i0);
1873 /* We use VOIDmode for integers. */
1877 /* Search the chain for an existing CONST_DOUBLE with the right value.
1878 If one is found, return it. */
1880 for (r = const_double_chain; r; r = CONST_DOUBLE_CHAIN (r))
1881 if (CONST_DOUBLE_LOW (r) == i0 && CONST_DOUBLE_HIGH (r) == i1
1882 && GET_MODE (r) == mode)
1885 /* No; make a new one and add it to the chain.
1887 We may be called by an optimizer which may be discarding any memory
1888 allocated during its processing (such as combine and loop). However,
1889 we will be leaving this constant on the chain, so we cannot tolerate
1890 freed memory. So switch to saveable_obstack for this allocation
1891 and then switch back if we were in current_obstack. */
1893 push_obstacks_nochange ();
1894 rtl_in_saveable_obstack ();
1895 r = gen_rtx (CONST_DOUBLE, mode, 0, i0, i1);
1898 /* Don't touch const_double_chain in nested function; see force_const_mem.
1899 Also, don't touch it if not inside any function. */
1900 if (outer_function_chain == 0 && current_function_decl != 0)
1902 CONST_DOUBLE_CHAIN (r) = const_double_chain;
1903 const_double_chain = r;
1906 /* Store const0_rtx in mem-slot since this CONST_DOUBLE is on the chain.
1907 Actual use of mem-slot is only through force_const_mem. */
1909 CONST_DOUBLE_MEM (r) = const0_rtx;
1914 /* Return a CONST_DOUBLE for a specified `double' value
1915 and machine mode. */
1918 immed_real_const_1 (d, mode)
1920 enum machine_mode mode;
1922 union real_extract u;
1924 int in_current_obstack;
1926 /* Get the desired `double' value as a sequence of ints
1927 since that is how they are stored in a CONST_DOUBLE. */
1931 /* Detect special cases. */
1933 /* Avoid REAL_VALUES_EQUAL here in order to distinguish minus zero. */
1934 if (!bcmp ((char *) &dconst0, (char *) &d, sizeof d))
1935 return CONST0_RTX (mode);
1936 /* Check for NaN first, because some ports (specifically the i386) do not
1937 emit correct ieee-fp code by default, and thus will generate a core
1938 dump here if we pass a NaN to REAL_VALUES_EQUAL and if REAL_VALUES_EQUAL
1939 does a floating point comparison. */
1940 else if (! REAL_VALUE_ISNAN (d) && REAL_VALUES_EQUAL (dconst1, d))
1941 return CONST1_RTX (mode);
1943 if (sizeof u == 2 * sizeof (HOST_WIDE_INT))
1944 return immed_double_const (u.i[0], u.i[1], mode);
1946 /* The rest of this function handles the case where
1947 a float value requires more than 2 ints of space.
1948 It will be deleted as dead code on machines that don't need it. */
1950 /* Search the chain for an existing CONST_DOUBLE with the right value.
1951 If one is found, return it. */
1953 for (r = const_double_chain; r; r = CONST_DOUBLE_CHAIN (r))
1954 if (! bcmp ((char *) &CONST_DOUBLE_LOW (r), (char *) &u, sizeof u)
1955 && GET_MODE (r) == mode)
1958 /* No; make a new one and add it to the chain.
1960 We may be called by an optimizer which may be discarding any memory
1961 allocated during its processing (such as combine and loop). However,
1962 we will be leaving this constant on the chain, so we cannot tolerate
1963 freed memory. So switch to saveable_obstack for this allocation
1964 and then switch back if we were in current_obstack. */
1966 push_obstacks_nochange ();
1967 rtl_in_saveable_obstack ();
1968 r = rtx_alloc (CONST_DOUBLE);
1970 bcopy ((char *) &u, (char *) &CONST_DOUBLE_LOW (r), sizeof u);
1973 /* Don't touch const_double_chain in nested function; see force_const_mem.
1974 Also, don't touch it if not inside any function. */
1975 if (outer_function_chain == 0 && current_function_decl != 0)
1977 CONST_DOUBLE_CHAIN (r) = const_double_chain;
1978 const_double_chain = r;
1981 /* Store const0_rtx in CONST_DOUBLE_MEM since this CONST_DOUBLE is on the
1982 chain, but has not been allocated memory. Actual use of CONST_DOUBLE_MEM
1983 is only through force_const_mem. */
1985 CONST_DOUBLE_MEM (r) = const0_rtx;
1990 /* Return a CONST_DOUBLE rtx for a value specified by EXP,
1991 which must be a REAL_CST tree node. */
1994 immed_real_const (exp)
1997 return immed_real_const_1 (TREE_REAL_CST (exp), TYPE_MODE (TREE_TYPE (exp)));
2000 /* At the end of a function, forget the memory-constants
2001 previously made for CONST_DOUBLEs. Mark them as not on real_constant_chain.
2002 Also clear out real_constant_chain and clear out all the chain-pointers. */
2005 clear_const_double_mem ()
2007 register rtx r, next;
2009 /* Don't touch CONST_DOUBLE_MEM for nested functions.
2010 See force_const_mem for explanation. */
2011 if (outer_function_chain != 0)
2014 for (r = const_double_chain; r; r = next)
2016 next = CONST_DOUBLE_CHAIN (r);
2017 CONST_DOUBLE_CHAIN (r) = 0;
2018 CONST_DOUBLE_MEM (r) = cc0_rtx;
2020 const_double_chain = 0;
2023 /* Given an expression EXP with a constant value,
2024 reduce it to the sum of an assembler symbol and an integer.
2025 Store them both in the structure *VALUE.
2026 Abort if EXP does not reduce. */
2031 HOST_WIDE_INT offset;
2035 decode_addr_const (exp, value)
2037 struct addr_const *value;
2039 register tree target = TREE_OPERAND (exp, 0);
2040 register int offset = 0;
2045 if (TREE_CODE (target) == COMPONENT_REF
2046 && (TREE_CODE (DECL_FIELD_BITPOS (TREE_OPERAND (target, 1)))
2049 offset += TREE_INT_CST_LOW (DECL_FIELD_BITPOS (TREE_OPERAND (target, 1))) / BITS_PER_UNIT;
2050 target = TREE_OPERAND (target, 0);
2052 else if (TREE_CODE (target) == ARRAY_REF)
2054 if (TREE_CODE (TREE_OPERAND (target, 1)) != INTEGER_CST
2055 || TREE_CODE (TYPE_SIZE (TREE_TYPE (target))) != INTEGER_CST)
2057 offset += ((TREE_INT_CST_LOW (TYPE_SIZE (TREE_TYPE (target)))
2058 * TREE_INT_CST_LOW (TREE_OPERAND (target, 1)))
2060 target = TREE_OPERAND (target, 0);
2066 switch (TREE_CODE (target))
2070 x = DECL_RTL (target);
2074 if (output_bytecode)
2075 /* FIXME: this may not be correct, check it */
2076 x = bc_gen_rtx (TREE_STRING_POINTER (target), 0, (struct bc_label *) 0);
2078 x = gen_rtx (MEM, FUNCTION_MODE,
2079 gen_rtx (LABEL_REF, VOIDmode,
2080 label_rtx (TREE_OPERAND (exp, 0))));
2087 x = TREE_CST_RTL (target);
2094 if (!output_bytecode)
2096 if (GET_CODE (x) != MEM)
2102 value->offset = offset;
2105 /* Uniquize all constants that appear in memory.
2106 Each constant in memory thus far output is recorded
2107 in `const_hash_table' with a `struct constant_descriptor'
2108 that contains a polish representation of the value of
2111 We cannot store the trees in the hash table
2112 because the trees may be temporary. */
2114 struct constant_descriptor
2116 struct constant_descriptor *next;
2122 #define MAX_HASH_TABLE 1009
2123 static struct constant_descriptor *const_hash_table[MAX_HASH_TABLE];
2125 /* Compute a hash code for a constant expression. */
2132 register int len, hi, i;
2133 register enum tree_code code = TREE_CODE (exp);
2135 if (code == INTEGER_CST)
2137 p = (char *) &TREE_INT_CST_LOW (exp);
2138 len = 2 * sizeof TREE_INT_CST_LOW (exp);
2140 else if (code == REAL_CST)
2142 p = (char *) &TREE_REAL_CST (exp);
2143 len = sizeof TREE_REAL_CST (exp);
2145 else if (code == STRING_CST)
2146 p = TREE_STRING_POINTER (exp), len = TREE_STRING_LENGTH (exp);
2147 else if (code == COMPLEX_CST)
2148 return const_hash (TREE_REALPART (exp)) * 5
2149 + const_hash (TREE_IMAGPART (exp));
2150 else if (code == CONSTRUCTOR && TREE_CODE (TREE_TYPE (exp)) == SET_TYPE)
2152 len = int_size_in_bytes (TREE_TYPE (exp));
2153 p = (char*) alloca (len);
2154 get_set_constructor_bytes (exp, (unsigned char *) p, len);
2156 else if (code == CONSTRUCTOR)
2160 /* For record type, include the type in the hashing.
2161 We do not do so for array types
2162 because (1) the sizes of the elements are sufficient
2163 and (2) distinct array types can have the same constructor.
2164 Instead, we include the array size because the constructor could
2166 if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE)
2167 hi = ((HOST_WIDE_INT) TREE_TYPE (exp) & ((1 << HASHBITS) - 1))
2170 hi = ((5 + int_size_in_bytes (TREE_TYPE (exp)))
2171 & ((1 << HASHBITS) - 1)) % MAX_HASH_TABLE;
2173 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link))
2174 if (TREE_VALUE (link))
2175 hi = (hi * 603 + const_hash (TREE_VALUE (link))) % MAX_HASH_TABLE;
2179 else if (code == ADDR_EXPR)
2181 struct addr_const value;
2182 decode_addr_const (exp, &value);
2183 if (GET_CODE (value.base) == SYMBOL_REF)
2185 /* Don't hash the address of the SYMBOL_REF;
2186 only use the offset and the symbol name. */
2188 p = XSTR (value.base, 0);
2189 for (i = 0; p[i] != 0; i++)
2190 hi = ((hi * 613) + (unsigned)(p[i]));
2192 else if (GET_CODE (value.base) == LABEL_REF)
2193 hi = value.offset + CODE_LABEL_NUMBER (XEXP (value.base, 0)) * 13;
2195 hi &= (1 << HASHBITS) - 1;
2196 hi %= MAX_HASH_TABLE;
2199 else if (code == PLUS_EXPR || code == MINUS_EXPR)
2200 return const_hash (TREE_OPERAND (exp, 0)) * 9
2201 + const_hash (TREE_OPERAND (exp, 1));
2202 else if (code == NOP_EXPR || code == CONVERT_EXPR)
2203 return const_hash (TREE_OPERAND (exp, 0)) * 7 + 2;
2205 /* Compute hashing function */
2207 for (i = 0; i < len; i++)
2208 hi = ((hi * 613) + (unsigned)(p[i]));
2210 hi &= (1 << HASHBITS) - 1;
2211 hi %= MAX_HASH_TABLE;
2215 /* Compare a constant expression EXP with a constant-descriptor DESC.
2216 Return 1 if DESC describes a constant with the same value as EXP. */
2219 compare_constant (exp, desc)
2221 struct constant_descriptor *desc;
2223 return 0 != compare_constant_1 (exp, desc->contents);
2226 /* Compare constant expression EXP with a substring P of a constant descriptor.
2227 If they match, return a pointer to the end of the substring matched.
2228 If they do not match, return 0.
2230 Since descriptors are written in polish prefix notation,
2231 this function can be used recursively to test one operand of EXP
2232 against a subdescriptor, and if it succeeds it returns the
2233 address of the subdescriptor for the next operand. */
2236 compare_constant_1 (exp, p)
2240 register char *strp;
2242 register enum tree_code code = TREE_CODE (exp);
2244 if (code != (enum tree_code) *p++)
2247 if (code == INTEGER_CST)
2249 /* Integer constants are the same only if the same width of type. */
2250 if (*p++ != TYPE_PRECISION (TREE_TYPE (exp)))
2252 strp = (char *) &TREE_INT_CST_LOW (exp);
2253 len = 2 * sizeof TREE_INT_CST_LOW (exp);
2255 else if (code == REAL_CST)
2257 /* Real constants are the same only if the same width of type. */
2258 if (*p++ != TYPE_PRECISION (TREE_TYPE (exp)))
2260 strp = (char *) &TREE_REAL_CST (exp);
2261 len = sizeof TREE_REAL_CST (exp);
2263 else if (code == STRING_CST)
2265 if (flag_writable_strings)
2267 strp = TREE_STRING_POINTER (exp);
2268 len = TREE_STRING_LENGTH (exp);
2269 if (bcmp ((char *) &TREE_STRING_LENGTH (exp), p,
2270 sizeof TREE_STRING_LENGTH (exp)))
2272 p += sizeof TREE_STRING_LENGTH (exp);
2274 else if (code == COMPLEX_CST)
2276 p = compare_constant_1 (TREE_REALPART (exp), p);
2277 if (p == 0) return 0;
2278 p = compare_constant_1 (TREE_IMAGPART (exp), p);
2281 else if (code == CONSTRUCTOR && TREE_CODE (TREE_TYPE (exp)) == SET_TYPE)
2283 len = int_size_in_bytes (TREE_TYPE (exp));
2284 strp = (char*) alloca (len);
2285 get_set_constructor_bytes (exp, (unsigned char *) strp, len);
2287 else if (code == CONSTRUCTOR)
2290 int length = list_length (CONSTRUCTOR_ELTS (exp));
2293 if (bcmp ((char *) &length, p, sizeof length))
2297 /* For record constructors, insist that the types match.
2298 For arrays, just verify both constructors are for arrays. */
2299 if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE)
2300 type = TREE_TYPE (exp);
2303 if (bcmp ((char *) &type, p, sizeof type))
2307 /* For arrays, insist that the size in bytes match. */
2308 if (TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE)
2310 int size = int_size_in_bytes (TREE_TYPE (exp));
2311 if (bcmp ((char *) &size, p, sizeof size))
2316 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link))
2318 if (TREE_VALUE (link))
2320 if ((p = compare_constant_1 (TREE_VALUE (link), p)) == 0)
2327 if (bcmp ((char *) &zero, p, sizeof zero))
2335 else if (code == ADDR_EXPR)
2337 struct addr_const value;
2338 decode_addr_const (exp, &value);
2339 strp = (char *) &value.offset;
2340 len = sizeof value.offset;
2341 /* Compare the offset. */
2343 if (*p++ != *strp++)
2345 /* Compare symbol name. */
2346 strp = XSTR (value.base, 0);
2347 len = strlen (strp) + 1;
2349 else if (code == PLUS_EXPR || code == MINUS_EXPR)
2351 p = compare_constant_1 (TREE_OPERAND (exp, 0), p);
2352 if (p == 0) return 0;
2353 p = compare_constant_1 (TREE_OPERAND (exp, 1), p);
2356 else if (code == NOP_EXPR || code == CONVERT_EXPR)
2358 p = compare_constant_1 (TREE_OPERAND (exp, 0), p);
2362 /* Compare constant contents. */
2364 if (*p++ != *strp++)
2370 /* Construct a constant descriptor for the expression EXP.
2371 It is up to the caller to enter the descriptor in the hash table. */
2373 static struct constant_descriptor *
2374 record_constant (exp)
2377 struct constant_descriptor *next = 0;
2380 /* Make a struct constant_descriptor. The first two pointers will
2381 be filled in later. Here we just leave space for them. */
2383 obstack_grow (&permanent_obstack, (char *) &next, sizeof next);
2384 obstack_grow (&permanent_obstack, (char *) &label, sizeof label);
2385 record_constant_1 (exp);
2386 return (struct constant_descriptor *) obstack_finish (&permanent_obstack);
2389 /* Add a description of constant expression EXP
2390 to the object growing in `permanent_obstack'.
2391 No need to return its address; the caller will get that
2392 from the obstack when the object is complete. */
2395 record_constant_1 (exp)
2398 register char *strp;
2400 register enum tree_code code = TREE_CODE (exp);
2402 obstack_1grow (&permanent_obstack, (unsigned int) code);
2407 obstack_1grow (&permanent_obstack, TYPE_PRECISION (TREE_TYPE (exp)));
2408 strp = (char *) &TREE_INT_CST_LOW (exp);
2409 len = 2 * sizeof TREE_INT_CST_LOW (exp);
2413 obstack_1grow (&permanent_obstack, TYPE_PRECISION (TREE_TYPE (exp)));
2414 strp = (char *) &TREE_REAL_CST (exp);
2415 len = sizeof TREE_REAL_CST (exp);
2419 if (flag_writable_strings)
2422 strp = TREE_STRING_POINTER (exp);
2423 len = TREE_STRING_LENGTH (exp);
2424 obstack_grow (&permanent_obstack, (char *) &TREE_STRING_LENGTH (exp),
2425 sizeof TREE_STRING_LENGTH (exp));
2429 record_constant_1 (TREE_REALPART (exp));
2430 record_constant_1 (TREE_IMAGPART (exp));
2434 if (TREE_CODE (TREE_TYPE (exp)) == SET_TYPE)
2436 int nbytes = int_size_in_bytes (TREE_TYPE (exp));
2437 obstack_grow (&permanent_obstack, &nbytes, sizeof (nbytes));
2438 obstack_blank (&permanent_obstack, nbytes);
2439 get_set_constructor_bytes
2440 (exp, (unsigned char *) permanent_obstack.next_free, nbytes);
2446 int length = list_length (CONSTRUCTOR_ELTS (exp));
2449 obstack_grow (&permanent_obstack, (char *) &length, sizeof length);
2451 /* For record constructors, insist that the types match.
2452 For arrays, just verify both constructors are for arrays. */
2453 if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE)
2454 type = TREE_TYPE (exp);
2457 obstack_grow (&permanent_obstack, (char *) &type, sizeof type);
2459 /* For arrays, insist that the size in bytes match. */
2460 if (TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE)
2462 int size = int_size_in_bytes (TREE_TYPE (exp));
2463 obstack_grow (&permanent_obstack, (char *) &size, sizeof size);
2466 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link))
2468 if (TREE_VALUE (link))
2469 record_constant_1 (TREE_VALUE (link));
2474 obstack_grow (&permanent_obstack,
2475 (char *) &zero, sizeof zero);
2483 struct addr_const value;
2485 decode_addr_const (exp, &value);
2486 /* Record the offset. */
2487 obstack_grow (&permanent_obstack,
2488 (char *) &value.offset, sizeof value.offset);
2489 /* Record the symbol name. */
2490 obstack_grow (&permanent_obstack, XSTR (value.base, 0),
2491 strlen (XSTR (value.base, 0)) + 1);
2497 record_constant_1 (TREE_OPERAND (exp, 0));
2498 record_constant_1 (TREE_OPERAND (exp, 1));
2503 case NON_LVALUE_EXPR:
2504 record_constant_1 (TREE_OPERAND (exp, 0));
2511 /* Record constant contents. */
2512 obstack_grow (&permanent_obstack, strp, len);
2515 /* Record a list of constant expressions that were passed to
2516 output_constant_def but that could not be output right away. */
2518 struct deferred_constant
2520 struct deferred_constant *next;
2526 static struct deferred_constant *deferred_constants;
2528 /* Nonzero means defer output of addressed subconstants
2529 (i.e., those for which output_constant_def is called.) */
2530 static int defer_addressed_constants_flag;
2532 /* Start deferring output of subconstants. */
2535 defer_addressed_constants ()
2537 defer_addressed_constants_flag++;
2540 /* Stop deferring output of subconstants,
2541 and output now all those that have been deferred. */
2544 output_deferred_addressed_constants ()
2546 struct deferred_constant *p, *next;
2548 defer_addressed_constants_flag--;
2550 if (defer_addressed_constants_flag > 0)
2553 for (p = deferred_constants; p; p = next)
2555 output_constant_def_contents (p->exp, p->reloc, p->labelno);
2560 deferred_constants = 0;
2563 /* Make a copy of the whole tree structure for a constant.
2564 This handles the same types of nodes that compare_constant
2565 and record_constant handle. */
2571 switch (TREE_CODE (exp))
2574 /* For ADDR_EXPR, we do not want to copy the decl whose address
2575 is requested. We do want to copy constants though. */
2576 if (TREE_CODE_CLASS (TREE_CODE (TREE_OPERAND (exp, 0))) == 'c')
2577 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
2578 copy_constant (TREE_OPERAND (exp, 0)));
2580 return copy_node (exp);
2585 return copy_node (exp);
2588 return build_complex (copy_constant (TREE_REALPART (exp)),
2589 copy_constant (TREE_IMAGPART (exp)));
2593 return build (TREE_CODE (exp), TREE_TYPE (exp),
2594 copy_constant (TREE_OPERAND (exp, 0)),
2595 copy_constant (TREE_OPERAND (exp, 1)));
2599 return build1 (TREE_CODE (exp), TREE_TYPE (exp),
2600 copy_constant (TREE_OPERAND (exp, 0)));
2604 tree copy = copy_node (exp);
2605 tree list = copy_list (CONSTRUCTOR_ELTS (exp));
2608 CONSTRUCTOR_ELTS (copy) = list;
2609 for (tail = list; tail; tail = TREE_CHAIN (tail))
2610 TREE_VALUE (tail) = copy_constant (TREE_VALUE (tail));
2611 if (TREE_CODE (TREE_TYPE (exp)) == SET_TYPE)
2612 for (tail = list; tail; tail = TREE_CHAIN (tail))
2613 TREE_PURPOSE (tail) = copy_constant (TREE_PURPOSE (tail));
2623 /* Return an rtx representing a reference to constant data in memory
2624 for the constant expression EXP.
2626 If assembler code for such a constant has already been output,
2627 return an rtx to refer to it.
2628 Otherwise, output such a constant in memory (or defer it for later)
2629 and generate an rtx for it.
2631 The TREE_CST_RTL of EXP is set up to point to that rtx.
2632 The const_hash_table records which constants already have label strings. */
2635 output_constant_def (exp)
2639 register struct constant_descriptor *desc;
2645 if (TREE_CODE (exp) == INTEGER_CST)
2646 abort (); /* No TREE_CST_RTL slot in these. */
2648 if (TREE_CST_RTL (exp))
2649 return TREE_CST_RTL (exp);
2651 /* Make sure any other constants whose addresses appear in EXP
2652 are assigned label numbers. */
2654 reloc = output_addressed_constants (exp);
2656 /* Compute hash code of EXP. Search the descriptors for that hash code
2657 to see if any of them describes EXP. If yes, the descriptor records
2658 the label number already assigned. */
2660 hash = const_hash (exp) % MAX_HASH_TABLE;
2662 for (desc = const_hash_table[hash]; desc; desc = desc->next)
2663 if (compare_constant (exp, desc))
2665 found = desc->label;
2671 /* No constant equal to EXP is known to have been output.
2672 Make a constant descriptor to enter EXP in the hash table.
2673 Assign the label number and record it in the descriptor for
2674 future calls to this function to find. */
2676 /* Create a string containing the label name, in LABEL. */
2677 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
2679 desc = record_constant (exp);
2680 desc->next = const_hash_table[hash];
2682 = (char *) obstack_copy0 (&permanent_obstack, label, strlen (label));
2683 const_hash_table[hash] = desc;
2687 /* Create a string containing the label name, in LABEL. */
2688 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
2691 /* We have a symbol name; construct the SYMBOL_REF and the MEM. */
2693 push_obstacks_nochange ();
2694 if (TREE_PERMANENT (exp))
2695 end_temporary_allocation ();
2697 def = gen_rtx (SYMBOL_REF, Pmode, desc->label);
2700 = gen_rtx (MEM, TYPE_MODE (TREE_TYPE (exp)), def);
2701 RTX_UNCHANGING_P (TREE_CST_RTL (exp)) = 1;
2702 if (AGGREGATE_TYPE_P (TREE_TYPE (exp)))
2703 MEM_IN_STRUCT_P (TREE_CST_RTL (exp)) = 1;
2707 /* Optionally set flags or add text to the name to record information
2708 such as that it is a function name. If the name is changed, the macro
2709 ASM_OUTPUT_LABELREF will have to know how to strip this information. */
2710 #ifdef ENCODE_SECTION_INFO
2711 ENCODE_SECTION_INFO (exp);
2714 /* If this is the first time we've seen this particular constant,
2715 output it (or defer its output for later). */
2718 if (defer_addressed_constants_flag)
2720 struct deferred_constant *p;
2721 p = (struct deferred_constant *) xmalloc (sizeof (struct deferred_constant));
2723 push_obstacks_nochange ();
2724 suspend_momentary ();
2725 p->exp = copy_constant (exp);
2728 p->labelno = const_labelno++;
2729 p->next = deferred_constants;
2730 deferred_constants = p;
2733 output_constant_def_contents (exp, reloc, const_labelno++);
2736 return TREE_CST_RTL (exp);
2739 /* Now output assembler code to define the label for EXP,
2740 and follow it with the data of EXP. */
2743 output_constant_def_contents (exp, reloc, labelno)
2750 if (IN_NAMED_SECTION (exp))
2751 named_section (exp, NULL);
2754 /* First switch to text section, except for writable strings. */
2755 #ifdef SELECT_SECTION
2756 SELECT_SECTION (exp, reloc);
2758 if (((TREE_CODE (exp) == STRING_CST) && flag_writable_strings)
2759 || (flag_pic && reloc))
2762 readonly_data_section ();
2766 /* Align the location counter as required by EXP's data type. */
2767 align = TYPE_ALIGN (TREE_TYPE (exp));
2768 #ifdef CONSTANT_ALIGNMENT
2769 align = CONSTANT_ALIGNMENT (exp, align);
2772 if (align > BITS_PER_UNIT)
2774 if (!output_bytecode)
2776 ASM_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2780 BC_OUTPUT_ALIGN (asm_out_file, floor_log2 (align / BITS_PER_UNIT));
2784 /* Output the label itself. */
2785 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LC", labelno);
2787 /* Output the value of EXP. */
2788 output_constant (exp,
2789 (TREE_CODE (exp) == STRING_CST
2790 ? TREE_STRING_LENGTH (exp)
2791 : int_size_in_bytes (TREE_TYPE (exp))));
2795 /* Similar hash facility for making memory-constants
2796 from constant rtl-expressions. It is used on RISC machines
2797 where immediate integer arguments and constant addresses are restricted
2798 so that such constants must be stored in memory.
2800 This pool of constants is reinitialized for each function
2801 so each function gets its own constants-pool that comes right before it.
2803 All structures allocated here are discarded when functions are saved for
2804 inlining, so they do not need to be allocated permanently. */
2806 #define MAX_RTX_HASH_TABLE 61
2807 static struct constant_descriptor **const_rtx_hash_table;
2809 /* Structure to represent sufficient information about a constant so that
2810 it can be output when the constant pool is output, so that function
2811 integration can be done, and to simplify handling on machines that reference
2812 constant pool as base+displacement. */
2814 struct pool_constant
2816 struct constant_descriptor *desc;
2817 struct pool_constant *next;
2818 enum machine_mode mode;
2825 /* Pointers to first and last constant in pool. */
2827 static struct pool_constant *first_pool, *last_pool;
2829 /* Current offset in constant pool (does not include any machine-specific
2832 static int pool_offset;
2834 /* Structure used to maintain hash table mapping symbols used to their
2835 corresponding constants. */
2840 struct pool_constant *pool;
2841 struct pool_sym *next;
2844 static struct pool_sym **const_rtx_sym_hash_table;
2846 /* Hash code for a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true.
2847 The argument is XSTR (... , 0) */
2849 #define SYMHASH(LABEL) \
2850 ((((HOST_WIDE_INT) (LABEL)) & ((1 << HASHBITS) - 1)) % MAX_RTX_HASH_TABLE)
2852 /* Initialize constant pool hashing for next function. */
2855 init_const_rtx_hash_table ()
2857 const_rtx_hash_table
2858 = ((struct constant_descriptor **)
2859 oballoc (MAX_RTX_HASH_TABLE * sizeof (struct constant_descriptor *)));
2860 const_rtx_sym_hash_table
2861 = ((struct pool_sym **)
2862 oballoc (MAX_RTX_HASH_TABLE * sizeof (struct pool_sym *)));
2863 bzero ((char *) const_rtx_hash_table,
2864 MAX_RTX_HASH_TABLE * sizeof (struct constant_descriptor *));
2865 bzero ((char *) const_rtx_sym_hash_table,
2866 MAX_RTX_HASH_TABLE * sizeof (struct pool_sym *));
2868 first_pool = last_pool = 0;
2872 /* Save and restore status for a nested function. */
2875 save_varasm_status (p)
2878 p->const_rtx_hash_table = const_rtx_hash_table;
2879 p->const_rtx_sym_hash_table = const_rtx_sym_hash_table;
2880 p->first_pool = first_pool;
2881 p->last_pool = last_pool;
2882 p->pool_offset = pool_offset;
2886 restore_varasm_status (p)
2889 const_rtx_hash_table = p->const_rtx_hash_table;
2890 const_rtx_sym_hash_table = p->const_rtx_sym_hash_table;
2891 first_pool = p->first_pool;
2892 last_pool = p->last_pool;
2893 pool_offset = p->pool_offset;
2896 enum kind { RTX_DOUBLE, RTX_INT };
2900 #ifdef ONLY_INT_FIELDS
2901 unsigned int kind : 16;
2902 unsigned int mode : 16;
2904 enum kind kind : 16;
2905 enum machine_mode mode : 16;
2908 union real_extract du;
2909 struct addr_const addr;
2913 /* Express an rtx for a constant integer (perhaps symbolic)
2914 as the sum of a symbol or label plus an explicit integer.
2915 They are stored into VALUE. */
2918 decode_rtx_const (mode, x, value)
2919 enum machine_mode mode;
2921 struct rtx_const *value;
2923 /* Clear the whole structure, including any gaps. */
2926 int *p = (int *) value;
2927 int *end = (int *) (value + 1);
2932 value->kind = RTX_INT; /* Most usual kind. */
2935 switch (GET_CODE (x))
2938 value->kind = RTX_DOUBLE;
2939 if (GET_MODE (x) != VOIDmode)
2940 value->mode = GET_MODE (x);
2941 bcopy ((char *) &CONST_DOUBLE_LOW (x),
2942 (char *) &value->un.du, sizeof value->un.du);
2946 value->un.addr.offset = INTVAL (x);
2952 value->un.addr.base = x;
2957 if (GET_CODE (x) == PLUS)
2959 value->un.addr.base = XEXP (x, 0);
2960 if (GET_CODE (XEXP (x, 1)) != CONST_INT)
2962 value->un.addr.offset = INTVAL (XEXP (x, 1));
2964 else if (GET_CODE (x) == MINUS)
2966 value->un.addr.base = XEXP (x, 0);
2967 if (GET_CODE (XEXP (x, 1)) != CONST_INT)
2969 value->un.addr.offset = - INTVAL (XEXP (x, 1));
2979 if (value->kind == RTX_INT && value->un.addr.base != 0)
2980 switch (GET_CODE (value->un.addr.base))
2984 /* Use the string's address, not the SYMBOL_REF's address,
2985 for the sake of addresses of library routines.
2986 For a LABEL_REF, compare labels. */
2987 value->un.addr.base = XEXP (value->un.addr.base, 0);
2991 /* Given a MINUS expression, simplify it if both sides
2992 include the same symbol. */
2995 simplify_subtraction (x)
2998 struct rtx_const val0, val1;
3000 decode_rtx_const (GET_MODE (x), XEXP (x, 0), &val0);
3001 decode_rtx_const (GET_MODE (x), XEXP (x, 1), &val1);
3003 if (val0.un.addr.base == val1.un.addr.base)
3004 return GEN_INT (val0.un.addr.offset - val1.un.addr.offset);
3008 /* Compute a hash code for a constant RTL expression. */
3011 const_hash_rtx (mode, x)
3012 enum machine_mode mode;
3017 struct rtx_const value;
3018 decode_rtx_const (mode, x, &value);
3020 /* Compute hashing function */
3022 for (i = 0; i < sizeof value / sizeof (int); i++)
3023 hi += ((int *) &value)[i];
3025 hi &= (1 << HASHBITS) - 1;
3026 hi %= MAX_RTX_HASH_TABLE;
3030 /* Compare a constant rtl object X with a constant-descriptor DESC.
3031 Return 1 if DESC describes a constant with the same value as X. */
3034 compare_constant_rtx (mode, x, desc)
3035 enum machine_mode mode;
3037 struct constant_descriptor *desc;
3039 register int *p = (int *) desc->contents;
3042 struct rtx_const value;
3044 decode_rtx_const (mode, x, &value);
3045 strp = (int *) &value;
3046 len = sizeof value / sizeof (int);
3048 /* Compare constant contents. */
3050 if (*p++ != *strp++)
3056 /* Construct a constant descriptor for the rtl-expression X.
3057 It is up to the caller to enter the descriptor in the hash table. */
3059 static struct constant_descriptor *
3060 record_constant_rtx (mode, x)
3061 enum machine_mode mode;
3064 struct constant_descriptor *ptr;
3066 struct rtx_const value;
3068 decode_rtx_const (mode, x, &value);
3070 /* Put these things in the saveable obstack so we can ensure it won't
3071 be freed if we are called from combine or some other phase that discards
3072 memory allocated from function_obstack (current_obstack). */
3073 obstack_grow (saveable_obstack, &ptr, sizeof ptr);
3074 obstack_grow (saveable_obstack, &label, sizeof label);
3076 /* Record constant contents. */
3077 obstack_grow (saveable_obstack, &value, sizeof value);
3079 return (struct constant_descriptor *) obstack_finish (saveable_obstack);
3082 /* Given a constant rtx X, make (or find) a memory constant for its value
3083 and return a MEM rtx to refer to it in memory. */
3086 force_const_mem (mode, x)
3087 enum machine_mode mode;
3091 register struct constant_descriptor *desc;
3096 /* If we want this CONST_DOUBLE in the same mode as it is in memory
3097 (this will always be true for floating CONST_DOUBLEs that have been
3098 placed in memory, but not for VOIDmode (integer) CONST_DOUBLEs),
3099 use the previous copy. Otherwise, make a new one. Note that in
3100 the unlikely event that this same CONST_DOUBLE is used in two different
3101 modes in an alternating fashion, we will allocate a lot of different
3102 memory locations, but this should be extremely rare. */
3104 /* Don't use CONST_DOUBLE_MEM in a nested function.
3105 Nested functions have their own constant pools,
3106 so they can't share the same values in CONST_DOUBLE_MEM
3107 with the containing function. */
3108 if (outer_function_chain == 0)
3109 if (GET_CODE (x) == CONST_DOUBLE
3110 && GET_CODE (CONST_DOUBLE_MEM (x)) == MEM
3111 && GET_MODE (CONST_DOUBLE_MEM (x)) == mode)
3112 return CONST_DOUBLE_MEM (x);
3114 /* Compute hash code of X. Search the descriptors for that hash code
3115 to see if any of them describes X. If yes, the descriptor records
3116 the label number already assigned. */
3118 hash = const_hash_rtx (mode, x);
3120 for (desc = const_rtx_hash_table[hash]; desc; desc = desc->next)
3121 if (compare_constant_rtx (mode, x, desc))
3123 found = desc->label;
3129 register struct pool_constant *pool;
3130 register struct pool_sym *sym;
3133 /* No constant equal to X is known to have been output.
3134 Make a constant descriptor to enter X in the hash table.
3135 Assign the label number and record it in the descriptor for
3136 future calls to this function to find. */
3138 desc = record_constant_rtx (mode, x);
3139 desc->next = const_rtx_hash_table[hash];
3140 const_rtx_hash_table[hash] = desc;
3142 /* Align the location counter as required by EXP's data type. */
3143 align = (mode == VOIDmode) ? UNITS_PER_WORD : GET_MODE_SIZE (mode);
3144 if (align > BIGGEST_ALIGNMENT / BITS_PER_UNIT)
3145 align = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
3147 pool_offset += align - 1;
3148 pool_offset &= ~ (align - 1);
3150 /* If RTL is not being placed into the saveable obstack, make a
3151 copy of X that is in the saveable obstack in case we are being
3152 called from combine or some other phase that discards memory
3153 it allocates. We need only do this if it is a CONST, since
3154 no other RTX should be allocated in this situation. */
3155 if (rtl_obstack != saveable_obstack
3156 && GET_CODE (x) == CONST)
3158 push_obstacks_nochange ();
3159 rtl_in_saveable_obstack ();
3161 x = gen_rtx (CONST, GET_MODE (x),
3162 gen_rtx (PLUS, GET_MODE (x),
3163 XEXP (XEXP (x, 0), 0), XEXP (XEXP (x, 0), 1)));
3167 /* Allocate a pool constant descriptor, fill it in, and chain it in. */
3169 pool = (struct pool_constant *) savealloc (sizeof (struct pool_constant));
3173 pool->labelno = const_labelno;
3174 pool->align = align;
3175 pool->offset = pool_offset;
3181 last_pool->next = pool;
3184 pool_offset += GET_MODE_SIZE (mode);
3186 /* Create a string containing the label name, in LABEL. */
3187 ASM_GENERATE_INTERNAL_LABEL (label, "LC", const_labelno);
3192 = (char *) obstack_copy0 (saveable_obstack, label, strlen (label));
3194 /* Add label to symbol hash table. */
3195 hash = SYMHASH (found);
3196 sym = (struct pool_sym *) savealloc (sizeof (struct pool_sym));
3199 sym->next = const_rtx_sym_hash_table[hash];
3200 const_rtx_sym_hash_table[hash] = sym;
3203 /* We have a symbol name; construct the SYMBOL_REF and the MEM. */
3205 def = gen_rtx (MEM, mode, gen_rtx (SYMBOL_REF, Pmode, found));
3207 RTX_UNCHANGING_P (def) = 1;
3208 /* Mark the symbol_ref as belonging to this constants pool. */
3209 CONSTANT_POOL_ADDRESS_P (XEXP (def, 0)) = 1;
3210 current_function_uses_const_pool = 1;
3212 if (outer_function_chain == 0)
3213 if (GET_CODE (x) == CONST_DOUBLE)
3215 if (CONST_DOUBLE_MEM (x) == cc0_rtx)
3217 CONST_DOUBLE_CHAIN (x) = const_double_chain;
3218 const_double_chain = x;
3220 CONST_DOUBLE_MEM (x) = def;
3226 /* Given a SYMBOL_REF with CONSTANT_POOL_ADDRESS_P true, return a pointer to
3227 the corresponding pool_constant structure. */
3229 static struct pool_constant *
3230 find_pool_constant (addr)
3233 struct pool_sym *sym;
3234 char *label = XSTR (addr, 0);
3236 for (sym = const_rtx_sym_hash_table[SYMHASH (label)]; sym; sym = sym->next)
3237 if (sym->label == label)
3243 /* Given a constant pool SYMBOL_REF, return the corresponding constant. */
3246 get_pool_constant (addr)
3249 return (find_pool_constant (addr))->constant;
3252 /* Similar, return the mode. */
3255 get_pool_mode (addr)
3258 return (find_pool_constant (addr))->mode;
3261 /* Similar, return the offset in the constant pool. */
3264 get_pool_offset (addr)
3267 return (find_pool_constant (addr))->offset;
3270 /* Return the size of the constant pool. */
3278 /* Write all the constants in the constant pool. */
3281 output_constant_pool (fnname, fndecl)
3285 struct pool_constant *pool;
3287 union real_extract u;
3289 #ifdef ASM_OUTPUT_POOL_PROLOGUE
3290 ASM_OUTPUT_POOL_PROLOGUE (asm_out_file, fnname, fndecl, pool_offset);
3293 for (pool = first_pool; pool; pool = pool->next)
3297 /* See if X is a LABEL_REF (or a CONST referring to a LABEL_REF)
3298 whose CODE_LABEL has been deleted. This can occur if a jump table
3299 is eliminated by optimization. If so, write a constant of zero
3300 instead. Note that this can also happen by turning the
3301 CODE_LABEL into a NOTE. */
3302 if (((GET_CODE (x) == LABEL_REF
3303 && (INSN_DELETED_P (XEXP (x, 0))
3304 || GET_CODE (XEXP (x, 0)) == NOTE)))
3305 || (GET_CODE (x) == CONST && GET_CODE (XEXP (x, 0)) == PLUS
3306 && GET_CODE (XEXP (XEXP (x, 0), 0)) == LABEL_REF
3307 && (INSN_DELETED_P (XEXP (XEXP (XEXP (x, 0), 0), 0))
3308 || GET_CODE (XEXP (XEXP (XEXP (x, 0), 0), 0)) == NOTE)))
3311 /* First switch to correct section. */
3312 #ifdef SELECT_RTX_SECTION
3313 SELECT_RTX_SECTION (pool->mode, x);
3315 readonly_data_section ();
3318 #ifdef ASM_OUTPUT_SPECIAL_POOL_ENTRY
3319 ASM_OUTPUT_SPECIAL_POOL_ENTRY (asm_out_file, x, pool->mode,
3320 pool->align, pool->labelno, done);
3323 if (pool->align > 1)
3324 ASM_OUTPUT_ALIGN (asm_out_file, exact_log2 (pool->align));
3326 /* Output the label. */
3327 ASM_OUTPUT_INTERNAL_LABEL (asm_out_file, "LC", pool->labelno);
3329 /* Output the value of the constant itself. */
3330 switch (GET_MODE_CLASS (pool->mode))
3333 if (GET_CODE (x) != CONST_DOUBLE)
3336 bcopy ((char *) &CONST_DOUBLE_LOW (x), (char *) &u, sizeof u);
3337 assemble_real (u.d, pool->mode);
3341 case MODE_PARTIAL_INT:
3342 assemble_integer (x, GET_MODE_SIZE (pool->mode), 1);
3352 /* Done with this pool. */
3353 first_pool = last_pool = 0;
3356 /* Find all the constants whose addresses are referenced inside of EXP,
3357 and make sure assembler code with a label has been output for each one.
3358 Indicate whether an ADDR_EXPR has been encountered. */
3361 output_addressed_constants (exp)
3366 switch (TREE_CODE (exp))
3370 register tree constant = TREE_OPERAND (exp, 0);
3372 while (TREE_CODE (constant) == COMPONENT_REF)
3374 constant = TREE_OPERAND (constant, 0);
3377 if (TREE_CODE_CLASS (TREE_CODE (constant)) == 'c'
3378 || TREE_CODE (constant) == CONSTRUCTOR)
3379 /* No need to do anything here
3380 for addresses of variables or functions. */
3381 output_constant_def (constant);
3388 reloc = output_addressed_constants (TREE_OPERAND (exp, 0));
3389 reloc |= output_addressed_constants (TREE_OPERAND (exp, 1));
3394 case NON_LVALUE_EXPR:
3395 reloc = output_addressed_constants (TREE_OPERAND (exp, 0));
3401 for (link = CONSTRUCTOR_ELTS (exp); link; link = TREE_CHAIN (link))
3402 if (TREE_VALUE (link) != 0)
3403 reloc |= output_addressed_constants (TREE_VALUE (link));
3413 /* Output assembler code for constant EXP to FILE, with no label.
3414 This includes the pseudo-op such as ".int" or ".byte", and a newline.
3415 Assumes output_addressed_constants has been done on EXP already.
3417 Generate exactly SIZE bytes of assembler data, padding at the end
3418 with zeros if necessary. SIZE must always be specified.
3420 SIZE is important for structure constructors,
3421 since trailing members may have been omitted from the constructor.
3422 It is also important for initialization of arrays from string constants
3423 since the full length of the string constant might not be wanted.
3424 It is also needed for initialization of unions, where the initializer's
3425 type is just one member, and that may not be as long as the union.
3427 There a case in which we would fail to output exactly SIZE bytes:
3428 for a structure constructor that wants to produce more than SIZE bytes.
3429 But such constructors will never be generated for any possible input. */
3432 output_constant (exp, size)
3436 register enum tree_code code = TREE_CODE (TREE_TYPE (exp));
3442 /* Eliminate the NON_LVALUE_EXPR_EXPR that makes a cast not be an lvalue.
3443 That way we get the constant (we hope) inside it. Also, strip off any
3444 NOP_EXPR that converts between two record, union, array, or set types. */
3445 while ((TREE_CODE (exp) == NOP_EXPR
3446 && (TREE_TYPE (exp) == TREE_TYPE (TREE_OPERAND (exp, 0))
3447 || AGGREGATE_TYPE_P (TREE_TYPE (exp))))
3448 || TREE_CODE (exp) == NON_LVALUE_EXPR)
3449 exp = TREE_OPERAND (exp, 0);
3451 /* Allow a constructor with no elements for any data type.
3452 This means to fill the space with zeros. */
3453 if (TREE_CODE (exp) == CONSTRUCTOR && CONSTRUCTOR_ELTS (exp) == 0)
3455 if (output_bytecode)
3456 bc_emit_const_skip (size);
3458 assemble_zeros (size);
3469 case REFERENCE_TYPE:
3470 /* ??? What about (int)((float)(int)&foo + 4) */
3471 while (TREE_CODE (exp) == NOP_EXPR || TREE_CODE (exp) == CONVERT_EXPR
3472 || TREE_CODE (exp) == NON_LVALUE_EXPR)
3473 exp = TREE_OPERAND (exp, 0);
3475 if (! assemble_integer (expand_expr (exp, NULL_RTX, VOIDmode,
3476 EXPAND_INITIALIZER),
3478 error ("initializer for integer value is too complicated");
3483 if (TREE_CODE (exp) != REAL_CST)
3484 error ("initializer for floating value is not a floating constant");
3486 assemble_real (TREE_REAL_CST (exp),
3487 mode_for_size (size * BITS_PER_UNIT, MODE_FLOAT, 0));
3492 output_constant (TREE_REALPART (exp), size / 2);
3493 output_constant (TREE_IMAGPART (exp), size / 2);
3494 size -= (size / 2) * 2;
3498 if (TREE_CODE (exp) == CONSTRUCTOR)
3500 output_constructor (exp, size);
3503 else if (TREE_CODE (exp) == STRING_CST)
3507 if (size > TREE_STRING_LENGTH (exp))
3509 excess = size - TREE_STRING_LENGTH (exp);
3510 size = TREE_STRING_LENGTH (exp);
3513 assemble_string (TREE_STRING_POINTER (exp), size);
3522 if (TREE_CODE (exp) == CONSTRUCTOR)
3523 output_constructor (exp, size);
3529 if (TREE_CODE (exp) == INTEGER_CST)
3530 assemble_integer (expand_expr (exp, NULL_RTX,
3531 VOIDmode, EXPAND_INITIALIZER),
3533 else if (TREE_CODE (exp) == CONSTRUCTOR)
3535 unsigned char *buffer = (unsigned char *) alloca (size);
3536 if (get_set_constructor_bytes (exp, buffer, size))
3538 assemble_string (buffer, size);
3541 error ("unknown set constructor type");
3546 assemble_zeros (size);
3549 /* Bytecode specific code to output assembler for integer. */
3552 bc_assemble_integer (exp, size)
3560 /* FIXME: is this fold() business going to be as good as the
3561 expand_expr() using EXPAND_SUM above in the RTL case? I
3563 FIXME: Copied as is from BC-GCC1; may need work. Don't hate. -bson */
3567 while (TREE_CODE (exp) == NOP_EXPR || TREE_CODE (exp) == CONVERT_EXPR)
3568 exp = TREE_OPERAND (exp, 0);
3569 if (TREE_CODE (exp) == INTEGER_CST)
3574 else if (TREE_CODE (exp) == PLUS_EXPR)
3576 const_part = TREE_OPERAND (exp, 0);
3577 while (TREE_CODE (const_part) == NOP_EXPR
3578 || TREE_CODE (const_part) == CONVERT_EXPR)
3579 const_part = TREE_OPERAND (const_part, 0);
3580 addr_part = TREE_OPERAND (exp, 1);
3581 while (TREE_CODE (addr_part) == NOP_EXPR
3582 || TREE_CODE (addr_part) == CONVERT_EXPR)
3583 addr_part = TREE_OPERAND (addr_part, 0);
3584 if (TREE_CODE (const_part) != INTEGER_CST)
3585 tmp = const_part, const_part = addr_part, addr_part = tmp;
3586 if (TREE_CODE (const_part) != INTEGER_CST
3587 || TREE_CODE (addr_part) != ADDR_EXPR)
3588 abort (); /* FIXME: we really haven't considered
3589 all the possible cases here. */
3591 else if (TREE_CODE (exp) == ADDR_EXPR)
3593 const_part = integer_zero_node;
3597 abort (); /* FIXME: ditto previous. */
3603 char c = TREE_INT_CST_LOW (const_part);
3609 short s = TREE_INT_CST_LOW (const_part);
3610 bc_emit ((char *) &s, 2);
3615 int i = TREE_INT_CST_LOW (const_part);
3616 bc_emit ((char *) &i, 4);
3621 if (WORDS_BIG_ENDIAN)
3623 int i = TREE_INT_CST_HIGH (const_part);
3624 bc_emit ((char *) &i, 4);
3625 i = TREE_INT_CST_LOW (const_part);
3626 bc_emit ((char *) &i, 4);
3630 int i = TREE_INT_CST_LOW (const_part);
3631 bc_emit ((char *) &i, 4);
3632 i = TREE_INT_CST_HIGH (const_part);
3633 bc_emit ((char *) &i, 4);
3640 && TREE_CODE (TREE_OPERAND (addr_part, 0)) == VAR_DECL)
3641 bc_emit_labelref (DECL_ASSEMBLER_NAME (TREE_OPERAND (addr_part, 0)),
3642 TREE_INT_CST_LOW (const_part));
3644 abort (); /* FIXME: there may be more cases. */
3647 /* Subroutine of output_constant, used for CONSTRUCTORs
3648 (aggregate constants).
3649 Generate at least SIZE bytes, padding if necessary. */
3652 output_constructor (exp, size)
3656 register tree link, field = 0;
3657 HOST_WIDE_INT min_index = 0;
3658 /* Number of bytes output or skipped so far.
3659 In other words, current position within the constructor. */
3660 int total_bytes = 0;
3661 /* Non-zero means BYTE contains part of a byte, to be output. */
3662 int byte_buffer_in_use = 0;
3665 if (HOST_BITS_PER_WIDE_INT < BITS_PER_UNIT)
3668 if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE)
3669 field = TYPE_FIELDS (TREE_TYPE (exp));
3671 if (TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE
3672 && TYPE_DOMAIN (TREE_TYPE (exp)) != 0)
3674 = TREE_INT_CST_LOW (TYPE_MIN_VALUE (TYPE_DOMAIN (TREE_TYPE (exp))));
3676 /* As LINK goes through the elements of the constant,
3677 FIELD goes through the structure fields, if the constant is a structure.
3678 if the constant is a union, then we override this,
3679 by getting the field from the TREE_LIST element.
3680 But the constant could also be an array. Then FIELD is zero. */
3681 for (link = CONSTRUCTOR_ELTS (exp);
3683 link = TREE_CHAIN (link),
3684 field = field ? TREE_CHAIN (field) : 0)
3686 tree val = TREE_VALUE (link);
3689 /* the element in a union constructor specifies the proper field. */
3691 if (TREE_CODE (TREE_TYPE (exp)) == RECORD_TYPE
3692 || TREE_CODE (TREE_TYPE (exp)) == UNION_TYPE)
3694 /* if available, use the type given by link */
3695 if (TREE_PURPOSE (link) != 0)
3696 field = TREE_PURPOSE (link);
3699 if (TREE_CODE (TREE_TYPE (exp)) == ARRAY_TYPE)
3700 index = TREE_PURPOSE (link);
3702 /* Eliminate the marker that makes a cast not be an lvalue. */
3706 if (field == 0 || !DECL_BIT_FIELD (field))
3708 /* An element that is not a bit-field. */
3710 register int fieldsize;
3711 /* Since this structure is static,
3712 we know the positions are constant. */
3713 int bitpos = (field ? (TREE_INT_CST_LOW (DECL_FIELD_BITPOS (field))
3717 bitpos = (TREE_INT_CST_LOW (TYPE_SIZE (TREE_TYPE (val)))
3719 * (TREE_INT_CST_LOW (index) - min_index));
3721 /* Output any buffered-up bit-fields preceding this element. */
3722 if (byte_buffer_in_use)
3724 ASM_OUTPUT_BYTE (asm_out_file, byte);
3726 byte_buffer_in_use = 0;
3729 /* Advance to offset of this element.
3730 Note no alignment needed in an array, since that is guaranteed
3731 if each element has the proper size. */
3732 if ((field != 0 || index != 0) && bitpos != total_bytes)
3734 if (!output_bytecode)
3735 assemble_zeros (bitpos - total_bytes);
3737 bc_emit_const_skip (bitpos - total_bytes);
3738 total_bytes = bitpos;
3741 /* Determine size this element should occupy. */
3744 if (TREE_CODE (DECL_SIZE (field)) != INTEGER_CST)
3746 if (TREE_INT_CST_LOW (DECL_SIZE (field)) > 100000)
3748 /* This avoids overflow trouble. */
3749 tree size_tree = size_binop (CEIL_DIV_EXPR,
3751 size_int (BITS_PER_UNIT));
3752 fieldsize = TREE_INT_CST_LOW (size_tree);
3756 fieldsize = TREE_INT_CST_LOW (DECL_SIZE (field));
3757 fieldsize = (fieldsize + BITS_PER_UNIT - 1) / BITS_PER_UNIT;
3761 fieldsize = int_size_in_bytes (TREE_TYPE (TREE_TYPE (exp)));
3763 /* Output the element's initial value. */
3765 assemble_zeros (fieldsize);
3767 output_constant (val, fieldsize);
3769 /* Count its size. */
3770 total_bytes += fieldsize;
3772 else if (val != 0 && TREE_CODE (val) != INTEGER_CST)
3773 error ("invalid initial value for member `%s'",
3774 IDENTIFIER_POINTER (DECL_NAME (field)));
3777 /* Element that is a bit-field. */
3779 int next_offset = TREE_INT_CST_LOW (DECL_FIELD_BITPOS (field));
3781 = (next_offset + TREE_INT_CST_LOW (DECL_SIZE (field)));
3784 val = integer_zero_node;
3786 /* If this field does not start in this (or, next) byte,
3788 if (next_offset / BITS_PER_UNIT != total_bytes)
3790 /* Output remnant of any bit field in previous bytes. */
3791 if (byte_buffer_in_use)
3793 ASM_OUTPUT_BYTE (asm_out_file, byte);
3795 byte_buffer_in_use = 0;
3798 /* If still not at proper byte, advance to there. */
3799 if (next_offset / BITS_PER_UNIT != total_bytes)
3801 assemble_zeros (next_offset / BITS_PER_UNIT - total_bytes);
3802 total_bytes = next_offset / BITS_PER_UNIT;
3806 if (! byte_buffer_in_use)
3809 /* We must split the element into pieces that fall within
3810 separate bytes, and combine each byte with previous or
3811 following bit-fields. */
3813 /* next_offset is the offset n fbits from the beginning of
3814 the structure to the next bit of this element to be processed.
3815 end_offset is the offset of the first bit past the end of
3817 while (next_offset < end_offset)
3821 HOST_WIDE_INT value;
3822 int next_byte = next_offset / BITS_PER_UNIT;
3823 int next_bit = next_offset % BITS_PER_UNIT;
3825 /* Advance from byte to byte
3826 within this element when necessary. */
3827 while (next_byte != total_bytes)
3829 ASM_OUTPUT_BYTE (asm_out_file, byte);
3834 /* Number of bits we can process at once
3835 (all part of the same byte). */
3836 this_time = MIN (end_offset - next_offset,
3837 BITS_PER_UNIT - next_bit);
3838 if (BYTES_BIG_ENDIAN)
3840 /* On big-endian machine, take the most significant bits
3841 first (of the bits that are significant)
3842 and put them into bytes from the most significant end. */
3843 shift = end_offset - next_offset - this_time;
3844 /* Don't try to take a bunch of bits that cross
3845 the word boundary in the INTEGER_CST. */
3846 if (shift < HOST_BITS_PER_WIDE_INT
3847 && shift + this_time > HOST_BITS_PER_WIDE_INT)
3849 this_time -= (HOST_BITS_PER_WIDE_INT - shift);
3850 shift = HOST_BITS_PER_WIDE_INT;
3853 /* Now get the bits from the appropriate constant word. */
3854 if (shift < HOST_BITS_PER_WIDE_INT)
3856 value = TREE_INT_CST_LOW (val);
3858 else if (shift < 2 * HOST_BITS_PER_WIDE_INT)
3860 value = TREE_INT_CST_HIGH (val);
3861 shift -= HOST_BITS_PER_WIDE_INT;
3865 byte |= (((value >> shift)
3866 & (((HOST_WIDE_INT) 1 << this_time) - 1))
3867 << (BITS_PER_UNIT - this_time - next_bit));
3871 /* On little-endian machines,
3872 take first the least significant bits of the value
3873 and pack them starting at the least significant
3874 bits of the bytes. */
3875 shift = (next_offset
3876 - TREE_INT_CST_LOW (DECL_FIELD_BITPOS (field)));
3877 /* Don't try to take a bunch of bits that cross
3878 the word boundary in the INTEGER_CST. */
3879 if (shift < HOST_BITS_PER_WIDE_INT
3880 && shift + this_time > HOST_BITS_PER_WIDE_INT)
3882 this_time -= (HOST_BITS_PER_WIDE_INT - shift);
3883 shift = HOST_BITS_PER_WIDE_INT;
3886 /* Now get the bits from the appropriate constant word. */
3887 if (shift < HOST_BITS_PER_INT)
3888 value = TREE_INT_CST_LOW (val);
3889 else if (shift < 2 * HOST_BITS_PER_WIDE_INT)
3891 value = TREE_INT_CST_HIGH (val);
3892 shift -= HOST_BITS_PER_WIDE_INT;
3896 byte |= (((value >> shift)
3897 & (((HOST_WIDE_INT) 1 << this_time) - 1))
3900 next_offset += this_time;
3901 byte_buffer_in_use = 1;
3905 if (byte_buffer_in_use)
3907 ASM_OUTPUT_BYTE (asm_out_file, byte);
3910 if (total_bytes < size)
3911 assemble_zeros (size - total_bytes);
3915 #ifdef HANDLE_SYSV_PRAGMA
3917 /* Support #pragma weak by default if WEAK_ASM_OP and ASM_OUTPUT_DEF
3919 #if defined (WEAK_ASM_OP) && defined (ASM_OUTPUT_DEF)
3921 /* See c-pragma.c for an identical definition. */
3937 /* Output asm to handle ``#pragma weak'' */
3939 handle_pragma_weak (what, asm_out_file, name, value)
3940 enum pragma_state what;
3944 if (what == ps_name || what == ps_value)
3946 fprintf (asm_out_file, "\t%s\t", WEAK_ASM_OP);
3948 if (output_bytecode)
3949 BC_OUTPUT_LABELREF (asm_out_file, name);
3951 ASM_OUTPUT_LABELREF (asm_out_file, name);
3953 fputc ('\n', asm_out_file);
3954 if (what == ps_value)
3955 ASM_OUTPUT_DEF (asm_out_file, name, value);
3957 else if (! (what == ps_done || what == ps_start))
3958 warning ("malformed `#pragma weak'");
3961 #endif /* HANDLE_PRAGMA_WEAK or (WEAK_ASM_OP and SET_ASM_OP) */
3963 #endif /* WEAK_ASM_OP && ASM_OUTPUT_DEF */