1 /* Allocate and read RTL for GNU C Compiler.
2 Copyright (C) 1987, 1988, 1991, 1994, 1997 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, 59 Temple Place - Suite 330,
19 Boston, MA 02111-1307, USA. */
29 #define obstack_chunk_alloc xmalloc
30 #define obstack_chunk_free free
32 /* Obstack used for allocating RTL objects.
33 Between functions, this is the permanent_obstack.
34 While parsing and expanding a function, this is maybepermanent_obstack
35 so we can save it if it is an inline function.
36 During optimization and output, this is function_obstack. */
38 extern struct obstack *rtl_obstack;
40 /* Indexed by rtx code, gives number of operands for an rtx with that code.
41 Does NOT include rtx header data (code and links).
42 This array is initialized in init_rtl. */
44 int rtx_length[NUM_RTX_CODE + 1];
46 /* Indexed by rtx code, gives the name of that kind of rtx, as a C string. */
48 #define DEF_RTL_EXPR(ENUM, NAME, FORMAT, CLASS) NAME ,
51 #include "rtl.def" /* rtl expressions are documented here */
56 /* Indexed by machine mode, gives the name of that machine mode.
57 This name does not include the letters "mode". */
59 #define DEF_MACHMODE(SYM, NAME, CLASS, SIZE, UNIT, WIDER) NAME,
61 char *mode_name[(int) MAX_MACHINE_MODE + 1] = {
62 #include "machmode.def"
67 /* Add an extra field to avoid a core dump if someone tries to convert
68 MAX_MACHINE_MODE to a string. */
74 /* Indexed by machine mode, gives the length of the mode, in bytes.
75 GET_MODE_CLASS uses this. */
77 #define DEF_MACHMODE(SYM, NAME, CLASS, SIZE, UNIT, WIDER) CLASS,
79 enum mode_class mode_class[(int) MAX_MACHINE_MODE] = {
80 #include "machmode.def"
85 /* Indexed by machine mode, gives the length of the mode, in bytes.
86 GET_MODE_SIZE uses this. */
88 #define DEF_MACHMODE(SYM, NAME, CLASS, SIZE, UNIT, WIDER) SIZE,
90 int mode_size[(int) MAX_MACHINE_MODE] = {
91 #include "machmode.def"
96 /* Indexed by machine mode, gives the length of the mode's subunit.
97 GET_MODE_UNIT_SIZE uses this. */
99 #define DEF_MACHMODE(SYM, NAME, CLASS, SIZE, UNIT, WIDER) UNIT,
101 int mode_unit_size[(int) MAX_MACHINE_MODE] = {
102 #include "machmode.def" /* machine modes are documented here */
107 /* Indexed by machine mode, gives next wider natural mode
108 (QI -> HI -> SI -> DI, etc.) Widening multiply instructions
111 #define DEF_MACHMODE(SYM, NAME, CLASS, SIZE, UNIT, WIDER) \
112 (unsigned char) WIDER,
114 unsigned char mode_wider_mode[(int) MAX_MACHINE_MODE] = {
115 #include "machmode.def" /* machine modes are documented here */
120 #define DEF_MACHMODE(SYM, NAME, CLASS, SIZE, UNIT, WIDER) \
121 ((SIZE) * BITS_PER_UNIT >= HOST_BITS_PER_WIDE_INT) ? ~(unsigned HOST_WIDE_INT)0 : ((unsigned HOST_WIDE_INT) 1 << (SIZE) * BITS_PER_UNIT) - 1,
123 /* Indexed by machine mode, gives mask of significant bits in mode. */
125 unsigned HOST_WIDE_INT mode_mask_array[(int) MAX_MACHINE_MODE] = {
126 #include "machmode.def"
129 /* Indexed by mode class, gives the narrowest mode for each class. */
131 enum machine_mode class_narrowest_mode[(int) MAX_MODE_CLASS];
133 /* Indexed by rtx code, gives a sequence of operand-types for
134 rtx's of that code. The sequence is a C string in which
135 each character describes one operand. */
137 char *rtx_format[] = {
139 can cause a warning message
140 "0" field is unused (or used in a phase-dependent manner)
144 "n" like "i", but prints entries from `note_insn_name'
145 "w" an integer of width HOST_BITS_PER_WIDE_INT
147 "s" a pointer to a string
149 "S" like "s", but optional:
150 the containing rtx may end before this operand
151 "e" a pointer to an rtl expression
152 prints the expression
153 "E" a pointer to a vector that points to a number of rtl expressions
154 prints a list of the rtl expressions
155 "V" like "E", but optional:
156 the containing rtx may end before this operand
157 "u" a pointer to another insn
158 prints the uid of the insn.
159 "b" is a pointer to a bitmap header.
160 "t" is a tree pointer. */
162 #define DEF_RTL_EXPR(ENUM, NAME, FORMAT, CLASS) FORMAT ,
163 #include "rtl.def" /* rtl expressions are defined here */
167 /* Indexed by rtx code, gives a character representing the "class" of
168 that rtx code. See rtl.def for documentation on the defined classes. */
171 #define DEF_RTL_EXPR(ENUM, NAME, FORMAT, CLASS) CLASS,
172 #include "rtl.def" /* rtl expressions are defined here */
176 /* Names for kinds of NOTEs and REG_NOTEs. */
178 char *note_insn_name[] = { 0 , "NOTE_INSN_DELETED",
179 "NOTE_INSN_BLOCK_BEG", "NOTE_INSN_BLOCK_END",
180 "NOTE_INSN_LOOP_BEG", "NOTE_INSN_LOOP_END",
181 "NOTE_INSN_FUNCTION_END", "NOTE_INSN_SETJMP",
182 "NOTE_INSN_LOOP_CONT", "NOTE_INSN_LOOP_VTOP",
183 "NOTE_INSN_PROLOGUE_END", "NOTE_INSN_EPILOGUE_BEG",
184 "NOTE_INSN_DELETED_LABEL", "NOTE_INSN_FUNCTION_BEG",
185 "NOTE_INSN_EH_REGION_BEG", "NOTE_INSN_EH_REGION_END",
186 "NOTE_REPEATED_LINE_NUMBER", "NOTE_INSN_RANGE_START",
187 "NOTE_INSN_RANGE_END", "NOTE_INSN_LIVE" };
189 char *reg_note_name[] = { "", "REG_DEAD", "REG_INC", "REG_EQUIV", "REG_WAS_0",
190 "REG_EQUAL", "REG_RETVAL", "REG_LIBCALL",
191 "REG_NONNEG", "REG_NO_CONFLICT", "REG_UNUSED",
192 "REG_CC_SETTER", "REG_CC_USER", "REG_LABEL",
193 "REG_DEP_ANTI", "REG_DEP_OUTPUT", "REG_BR_PROB",
194 "REG_EXEC_COUNT", "REG_NOALIAS", "REG_SAVE_AREA",
195 "REG_BR_PRED", "REG_EH_CONTEXT",
196 "REG_FRAME_RELATED_EXPR" };
198 static void dump_and_abort PROTO((int, int, FILE *)) ATTRIBUTE_NORETURN;
199 static void read_name PROTO((char *, FILE *));
201 /* Allocate an rtx vector of N elements.
202 Store the length, and initialize all elements to zero. */
211 rt = (rtvec) obstack_alloc (rtl_obstack,
212 sizeof (struct rtvec_def)
213 + (( n - 1) * sizeof (rtunion)));
215 /* clear out the vector */
216 PUT_NUM_ELEM (rt, n);
218 for (i = 0; i < n; i++)
219 rt->elem[i].rtwint = 0;
224 /* Allocate an rtx of code CODE. The CODE is stored in the rtx;
225 all the rest is initialized to zero. */
232 register struct obstack *ob = rtl_obstack;
233 register int nelts = GET_RTX_LENGTH (code);
234 register int length = sizeof (struct rtx_def)
235 + (nelts - 1) * sizeof (rtunion);
237 /* This function is called more than any other in GCC,
238 so we manipulate the obstack directly.
240 Even though rtx objects are word aligned, we may be sharing an obstack
241 with tree nodes, which may have to be double-word aligned. So align
242 our length to the alignment mask in the obstack. */
244 length = (length + ob->alignment_mask) & ~ ob->alignment_mask;
246 if (ob->chunk_limit - ob->next_free < length)
247 _obstack_newchunk (ob, length);
248 rt = (rtx)ob->object_base;
249 ob->next_free += length;
250 ob->object_base = ob->next_free;
252 /* We want to clear everything up to the FLD array. Normally, this is
253 one int, but we don't want to assume that and it isn't very portable
256 length = (sizeof (struct rtx_def) - sizeof (rtunion) - 1) / sizeof (int);
257 for (; length >= 0; length--)
258 ((int *) rt)[length] = 0;
265 /* Free the rtx X and all RTL allocated since X. */
271 obstack_free (rtl_obstack, x);
274 /* Create a new copy of an rtx.
275 Recursively copies the operands of the rtx,
276 except for those few rtx codes that are sharable. */
284 register RTX_CODE code;
285 register char *format_ptr;
287 code = GET_CODE (orig);
300 /* SCRATCH must be shared because they represent distinct values. */
305 /* CONST can be shared if it contains a SYMBOL_REF. If it contains
306 a LABEL_REF, it isn't sharable. */
307 if (GET_CODE (XEXP (orig, 0)) == PLUS
308 && GET_CODE (XEXP (XEXP (orig, 0), 0)) == SYMBOL_REF
309 && GET_CODE (XEXP (XEXP (orig, 0), 1)) == CONST_INT)
313 /* A MEM with a constant address is not sharable. The problem is that
314 the constant address may need to be reloaded. If the mem is shared,
315 then reloading one copy of this mem will cause all copies to appear
316 to have been reloaded. */
322 copy = rtx_alloc (code);
323 PUT_MODE (copy, GET_MODE (orig));
324 copy->in_struct = orig->in_struct;
325 copy->volatil = orig->volatil;
326 copy->unchanging = orig->unchanging;
327 copy->integrated = orig->integrated;
329 format_ptr = GET_RTX_FORMAT (GET_CODE (copy));
331 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (copy)); i++)
333 switch (*format_ptr++)
336 XEXP (copy, i) = XEXP (orig, i);
337 if (XEXP (orig, i) != NULL)
338 XEXP (copy, i) = copy_rtx (XEXP (orig, i));
343 XEXP (copy, i) = XEXP (orig, i);
348 XVEC (copy, i) = XVEC (orig, i);
349 if (XVEC (orig, i) != NULL)
351 XVEC (copy, i) = rtvec_alloc (XVECLEN (orig, i));
352 for (j = 0; j < XVECLEN (copy, i); j++)
353 XVECEXP (copy, i, j) = copy_rtx (XVECEXP (orig, i, j));
359 bitmap new_bits = BITMAP_OBSTACK_ALLOC (rtl_obstack);
360 bitmap_copy (new_bits, XBITMAP (orig, i));
361 XBITMAP (copy, i) = new_bits;
366 XTREE (copy, i) = XTREE (orig, i);
370 XWINT (copy, i) = XWINT (orig, i);
374 XINT (copy, i) = XINT (orig, i);
379 XSTR (copy, i) = XSTR (orig, i);
389 /* Similar to `copy_rtx' except that if MAY_SHARE is present, it is
390 placed in the result directly, rather than being copied. */
393 copy_most_rtx (orig, may_share)
395 register rtx may_share;
399 register RTX_CODE code;
400 register char *format_ptr;
402 if (orig == may_share)
405 code = GET_CODE (orig);
422 copy = rtx_alloc (code);
423 PUT_MODE (copy, GET_MODE (orig));
424 copy->in_struct = orig->in_struct;
425 copy->volatil = orig->volatil;
426 copy->unchanging = orig->unchanging;
427 copy->integrated = orig->integrated;
429 format_ptr = GET_RTX_FORMAT (GET_CODE (copy));
431 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (copy)); i++)
433 switch (*format_ptr++)
436 XEXP (copy, i) = XEXP (orig, i);
437 if (XEXP (orig, i) != NULL && XEXP (orig, i) != may_share)
438 XEXP (copy, i) = copy_most_rtx (XEXP (orig, i), may_share);
443 XEXP (copy, i) = XEXP (orig, i);
448 XVEC (copy, i) = XVEC (orig, i);
449 if (XVEC (orig, i) != NULL)
451 XVEC (copy, i) = rtvec_alloc (XVECLEN (orig, i));
452 for (j = 0; j < XVECLEN (copy, i); j++)
454 = copy_most_rtx (XVECEXP (orig, i, j), may_share);
459 XWINT (copy, i) = XWINT (orig, i);
464 XINT (copy, i) = XINT (orig, i);
469 XSTR (copy, i) = XSTR (orig, i);
479 /* Subroutines of read_rtx. */
481 /* Dump code after printing a message. Used when read_rtx finds
485 dump_and_abort (expected_c, actual_c, infile)
486 int expected_c, actual_c;
493 "Expected character %c. Found character %c.",
494 expected_c, actual_c);
495 fprintf (stderr, " At file position: %ld\n", ftell (infile));
496 fprintf (stderr, "Following characters are:\n\t");
497 for (i = 0; i < 200; i++)
503 fprintf (stderr, "Aborting.\n");
507 /* Read chars from INFILE until a non-whitespace char
508 and return that. Comments, both Lisp style and C style,
509 are treated as whitespace.
510 Tools such as genflags use this function. */
513 read_skip_spaces (infile)
517 while ((c = getc (infile)))
519 if (c == ' ' || c == '\n' || c == '\t' || c == '\f')
523 while ((c = getc (infile)) && c != '\n' && c != EOF)
531 dump_and_abort ('*', c, infile);
534 while ((c = getc (infile)) && c != EOF)
536 if (prevc == '*' && c == '/')
546 /* Read an rtx code name into the buffer STR[].
547 It is terminated by any of the punctuation chars of rtx printed syntax. */
550 read_name (str, infile)
557 c = read_skip_spaces(infile);
562 if (c == ' ' || c == '\n' || c == '\t' || c == '\f')
564 if (c == ':' || c == ')' || c == ']' || c == '"' || c == '/'
565 || c == '(' || c == '[')
575 fprintf (stderr, "missing name or number");
576 dump_and_abort (-1, -1, infile);
582 /* Provide a version of a function to read a long long if the system does
584 #if HOST_BITS_PER_WIDE_INT > HOST_BITS_PER_LONG && !defined(HAVE_ATOLL) && !defined(HAVE_ATOQ)
590 HOST_WIDE_INT tmp_wide;
602 HOST_WIDE_INT new_wide = tmp_wide*10 + (*p - '0');
603 if (new_wide < tmp_wide)
605 /* Return INT_MAX equiv on overflow. */
606 tmp_wide = (~(unsigned HOST_WIDE_INT)0) >> 1;
614 tmp_wide = -tmp_wide;
619 /* Read an rtx in printed representation from INFILE
620 and return an actual rtx in core constructed accordingly.
621 read_rtx is not used in the compiler proper, but rather in
622 the utilities gen*.c that construct C code from machine descriptions. */
628 register int i, j, list_counter;
630 register char *format_ptr;
631 /* tmp_char is a buffer used for reading decimal integers
632 and names of rtx types and machine modes.
633 Therefore, 256 must be enough. */
638 HOST_WIDE_INT tmp_wide;
640 /* Linked list structure for making RTXs: */
643 struct rtx_list *next;
644 rtx value; /* Value of this node... */
647 c = read_skip_spaces (infile); /* Should be open paren. */
649 dump_and_abort ('(', c, infile);
651 read_name (tmp_char, infile);
655 for (i=0; i < NUM_RTX_CODE; i++) /* @@ might speed this search up */
657 if (!(strcmp (tmp_char, GET_RTX_NAME (i))))
659 tmp_code = (RTX_CODE) i; /* get value for name */
663 if (tmp_code == UNKNOWN)
666 "Unknown rtx read in rtl.read_rtx(). Code name was %s .",
669 /* (NIL) stands for an expression that isn't there. */
672 /* Discard the closeparen. */
673 while ((c = getc (infile)) && c != ')');
677 return_rtx = rtx_alloc (tmp_code); /* if we end up with an insn expression
678 then we free this space below. */
679 format_ptr = GET_RTX_FORMAT (GET_CODE (return_rtx));
681 /* If what follows is `: mode ', read it and
682 store the mode in the rtx. */
684 i = read_skip_spaces (infile);
688 read_name (tmp_char, infile);
689 for (k = 0; k < NUM_MACHINE_MODES; k++)
690 if (!strcmp (GET_MODE_NAME (k), tmp_char))
693 PUT_MODE (return_rtx, (enum machine_mode) k );
698 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (return_rtx)); i++)
699 switch (*format_ptr++)
701 /* 0 means a field for internal use only.
702 Don't expect it to be present in the input. */
708 XEXP (return_rtx, i) = read_rtx (infile);
712 /* 'V' is an optional vector: if a closeparen follows,
713 just store NULL for this element. */
714 c = read_skip_spaces (infile);
718 XVEC (return_rtx, i) = 0;
721 /* Now process the vector. */
725 register struct rtx_list *next_rtx, *rtx_list_link;
726 struct rtx_list *list_rtx = NULL;
728 c = read_skip_spaces (infile);
730 dump_and_abort ('[', c, infile);
732 /* add expressions to a list, while keeping a count */
735 while ((c = read_skip_spaces (infile)) && c != ']')
739 rtx_list_link = (struct rtx_list *)
740 alloca (sizeof (struct rtx_list));
741 rtx_list_link->value = read_rtx (infile);
743 list_rtx = rtx_list_link;
745 next_rtx->next = rtx_list_link;
746 next_rtx = rtx_list_link;
747 rtx_list_link->next = 0;
749 /* get vector length and allocate it */
750 XVEC (return_rtx, i) = (list_counter
751 ? rtvec_alloc (list_counter) : NULL_RTVEC);
752 if (list_counter > 0)
755 for (j = 0; j < list_counter; j++,
756 next_rtx = next_rtx->next)
757 XVECEXP (return_rtx, i, j) = next_rtx->value;
759 /* close bracket gotten */
764 /* 'S' is an optional string: if a closeparen follows,
765 just store NULL for this element. */
766 c = read_skip_spaces (infile);
770 XSTR (return_rtx, i) = 0;
777 register char *stringbuf;
779 c = read_skip_spaces (infile);
783 c = read_skip_spaces (infile);
786 dump_and_abort ('"', c, infile);
790 c = getc (infile); /* Read the string */
793 c = getc (infile); /* Read the string */
794 /* \; makes stuff for a C string constant containing
798 obstack_grow (rtl_obstack, "\\n\\t", 4);
805 obstack_1grow (rtl_obstack, c);
808 obstack_1grow (rtl_obstack, 0);
809 stringbuf = (char *) obstack_finish (rtl_obstack);
813 c = read_skip_spaces (infile);
815 dump_and_abort (')', c, infile);
817 XSTR (return_rtx, i) = stringbuf;
822 read_name (tmp_char, infile);
823 #if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_INT
824 tmp_wide = atoi (tmp_char);
826 #if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONG
827 tmp_wide = atol (tmp_char);
829 /* Prefer atoll over atoq, since the former is in the ISO C9X draft.
830 But prefer not to use our hand-rolled function above either. */
831 #if defined(HAVE_ATOLL) || !defined(HAVE_ATOQ)
832 tmp_wide = atoll (tmp_char);
834 tmp_wide = atoq (tmp_char);
838 XWINT (return_rtx, i) = tmp_wide;
843 read_name (tmp_char, infile);
844 tmp_int = atoi (tmp_char);
845 XINT (return_rtx, i) = tmp_int;
850 "switch format wrong in rtl.read_rtx(). format was: %c.\n",
852 fprintf (stderr, "\tfile position: %ld\n", ftell (infile));
856 c = read_skip_spaces (infile);
858 dump_and_abort (')', c, infile);
863 /* This is called once per compilation, before any rtx's are constructed.
864 It initializes the vector `rtx_length', the extra CC modes, if any,
865 and computes certain commonly-used modes. */
870 int min_class_size[(int) MAX_MODE_CLASS];
871 enum machine_mode mode;
874 for (i = 0; i < NUM_RTX_CODE; i++)
875 rtx_length[i] = strlen (rtx_format[i]);
877 /* Make CONST_DOUBLE bigger, if real values are bigger than
878 it normally expects to have room for.
879 Note that REAL_VALUE_TYPE is not defined by default,
880 since tree.h is not included. But the default dfn as `double'
882 #ifdef REAL_VALUE_TYPE
883 i = sizeof (REAL_VALUE_TYPE) / sizeof (rtunion) + 2;
884 if (rtx_length[(int) CONST_DOUBLE] < i)
886 char *s = (char *) xmalloc (i + 1);
887 rtx_length[(int) CONST_DOUBLE] = i;
888 rtx_format[(int) CONST_DOUBLE] = s;
891 /* Set the GET_RTX_FORMAT of CONST_DOUBLE to a string
892 of as many `w's as we now have elements. Subtract two from
893 the size to account for the 'e' and the '0'. */
894 for (i = 2; i < rtx_length[(int) CONST_DOUBLE]; i++)
900 #ifdef EXTRA_CC_MODES
901 for (i = (int) CCmode + 1; i < (int) MAX_MACHINE_MODE; i++)
903 mode_class[i] = MODE_CC;
904 mode_mask_array[i] = mode_mask_array[(int) CCmode];
905 mode_size[i] = mode_size[(int) CCmode];
906 mode_unit_size[i] = mode_unit_size[(int) CCmode];
907 mode_wider_mode[i - 1] = i;
908 mode_wider_mode[i] = (unsigned char)VOIDmode;
912 /* Find the narrowest mode for each class. */
914 for (i = 0; i < (int) MAX_MODE_CLASS; i++)
915 min_class_size[i] = 1000;
917 for (mode = VOIDmode; (int) mode < (int) MAX_MACHINE_MODE;
918 mode = (enum machine_mode) ((int) mode + 1))
920 if (GET_MODE_SIZE (mode) < min_class_size[(int) GET_MODE_CLASS (mode)])
922 class_narrowest_mode[(int) GET_MODE_CLASS (mode)] = mode;
923 min_class_size[(int) GET_MODE_CLASS (mode)] = GET_MODE_SIZE (mode);