1 /* Allocate and read RTL for GNU C Compiler.
2 Copyright (C) 1987, 1988, 1991, 1994, 1997, 1998 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", "REG_EH_REGION",
199 static void dump_and_abort PROTO((int, int, FILE *)) ATTRIBUTE_NORETURN;
200 static void read_name PROTO((char *, FILE *));
202 /* Allocate an rtx vector of N elements.
203 Store the length, and initialize all elements to zero. */
212 rt = (rtvec) obstack_alloc (rtl_obstack,
213 sizeof (struct rtvec_def)
214 + (( n - 1) * sizeof (rtunion)));
216 /* clear out the vector */
217 PUT_NUM_ELEM (rt, n);
219 for (i = 0; i < n; i++)
220 rt->elem[i].rtwint = 0;
225 /* Allocate an rtx of code CODE. The CODE is stored in the rtx;
226 all the rest is initialized to zero. */
233 register struct obstack *ob = rtl_obstack;
234 register int nelts = GET_RTX_LENGTH (code);
235 register int length = sizeof (struct rtx_def)
236 + (nelts - 1) * sizeof (rtunion);
238 /* This function is called more than any other in GCC,
239 so we manipulate the obstack directly.
241 Even though rtx objects are word aligned, we may be sharing an obstack
242 with tree nodes, which may have to be double-word aligned. So align
243 our length to the alignment mask in the obstack. */
245 length = (length + ob->alignment_mask) & ~ ob->alignment_mask;
247 if (ob->chunk_limit - ob->next_free < length)
248 _obstack_newchunk (ob, length);
249 rt = (rtx)ob->object_base;
250 ob->next_free += length;
251 ob->object_base = ob->next_free;
253 /* We want to clear everything up to the FLD array. Normally, this is
254 one int, but we don't want to assume that and it isn't very portable
257 length = (sizeof (struct rtx_def) - sizeof (rtunion) - 1) / sizeof (int);
258 for (; length >= 0; length--)
259 ((int *) rt)[length] = 0;
266 /* Free the rtx X and all RTL allocated since X. */
272 obstack_free (rtl_obstack, x);
275 /* Create a new copy of an rtx.
276 Recursively copies the operands of the rtx,
277 except for those few rtx codes that are sharable. */
285 register RTX_CODE code;
286 register char *format_ptr;
288 code = GET_CODE (orig);
301 /* SCRATCH must be shared because they represent distinct values. */
306 /* CONST can be shared if it contains a SYMBOL_REF. If it contains
307 a LABEL_REF, it isn't sharable. */
308 if (GET_CODE (XEXP (orig, 0)) == PLUS
309 && GET_CODE (XEXP (XEXP (orig, 0), 0)) == SYMBOL_REF
310 && GET_CODE (XEXP (XEXP (orig, 0), 1)) == CONST_INT)
314 /* A MEM with a constant address is not sharable. The problem is that
315 the constant address may need to be reloaded. If the mem is shared,
316 then reloading one copy of this mem will cause all copies to appear
317 to have been reloaded. */
323 copy = rtx_alloc (code);
324 PUT_MODE (copy, GET_MODE (orig));
325 copy->in_struct = orig->in_struct;
326 copy->volatil = orig->volatil;
327 copy->unchanging = orig->unchanging;
328 copy->integrated = orig->integrated;
330 format_ptr = GET_RTX_FORMAT (GET_CODE (copy));
332 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (copy)); i++)
334 switch (*format_ptr++)
337 XEXP (copy, i) = XEXP (orig, i);
338 if (XEXP (orig, i) != NULL)
339 XEXP (copy, i) = copy_rtx (XEXP (orig, i));
344 XEXP (copy, i) = XEXP (orig, i);
349 XVEC (copy, i) = XVEC (orig, i);
350 if (XVEC (orig, i) != NULL)
352 XVEC (copy, i) = rtvec_alloc (XVECLEN (orig, i));
353 for (j = 0; j < XVECLEN (copy, i); j++)
354 XVECEXP (copy, i, j) = copy_rtx (XVECEXP (orig, i, j));
360 bitmap new_bits = BITMAP_OBSTACK_ALLOC (rtl_obstack);
361 bitmap_copy (new_bits, XBITMAP (orig, i));
362 XBITMAP (copy, i) = new_bits;
367 XTREE (copy, i) = XTREE (orig, i);
371 XWINT (copy, i) = XWINT (orig, i);
375 XINT (copy, i) = XINT (orig, i);
380 XSTR (copy, i) = XSTR (orig, i);
390 /* Similar to `copy_rtx' except that if MAY_SHARE is present, it is
391 placed in the result directly, rather than being copied. */
394 copy_most_rtx (orig, may_share)
396 register rtx may_share;
400 register RTX_CODE code;
401 register char *format_ptr;
403 if (orig == may_share)
406 code = GET_CODE (orig);
423 copy = rtx_alloc (code);
424 PUT_MODE (copy, GET_MODE (orig));
425 copy->in_struct = orig->in_struct;
426 copy->volatil = orig->volatil;
427 copy->unchanging = orig->unchanging;
428 copy->integrated = orig->integrated;
430 format_ptr = GET_RTX_FORMAT (GET_CODE (copy));
432 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (copy)); i++)
434 switch (*format_ptr++)
437 XEXP (copy, i) = XEXP (orig, i);
438 if (XEXP (orig, i) != NULL && XEXP (orig, i) != may_share)
439 XEXP (copy, i) = copy_most_rtx (XEXP (orig, i), may_share);
444 XEXP (copy, i) = XEXP (orig, i);
449 XVEC (copy, i) = XVEC (orig, i);
450 if (XVEC (orig, i) != NULL)
452 XVEC (copy, i) = rtvec_alloc (XVECLEN (orig, i));
453 for (j = 0; j < XVECLEN (copy, i); j++)
455 = copy_most_rtx (XVECEXP (orig, i, j), may_share);
460 XWINT (copy, i) = XWINT (orig, i);
465 XINT (copy, i) = XINT (orig, i);
470 XSTR (copy, i) = XSTR (orig, i);
480 /* Subroutines of read_rtx. */
482 /* Dump code after printing a message. Used when read_rtx finds
486 dump_and_abort (expected_c, actual_c, infile)
487 int expected_c, actual_c;
494 "Expected character %c. Found character %c.",
495 expected_c, actual_c);
496 fprintf (stderr, " At file position: %ld\n", ftell (infile));
497 fprintf (stderr, "Following characters are:\n\t");
498 for (i = 0; i < 200; i++)
504 fprintf (stderr, "Aborting.\n");
508 /* Read chars from INFILE until a non-whitespace char
509 and return that. Comments, both Lisp style and C style,
510 are treated as whitespace.
511 Tools such as genflags use this function. */
514 read_skip_spaces (infile)
518 while ((c = getc (infile)))
520 if (c == ' ' || c == '\n' || c == '\t' || c == '\f')
524 while ((c = getc (infile)) && c != '\n' && c != EOF)
532 dump_and_abort ('*', c, infile);
535 while ((c = getc (infile)) && c != EOF)
537 if (prevc == '*' && c == '/')
547 /* Read an rtx code name into the buffer STR[].
548 It is terminated by any of the punctuation chars of rtx printed syntax. */
551 read_name (str, infile)
558 c = read_skip_spaces(infile);
563 if (c == ' ' || c == '\n' || c == '\t' || c == '\f')
565 if (c == ':' || c == ')' || c == ']' || c == '"' || c == '/'
566 || c == '(' || c == '[')
576 fprintf (stderr, "missing name or number");
577 dump_and_abort (-1, -1, infile);
583 /* Provide a version of a function to read a long long if the system does
585 #if HOST_BITS_PER_WIDE_INT > HOST_BITS_PER_LONG && !defined(HAVE_ATOLL) && !defined(HAVE_ATOQ)
591 HOST_WIDE_INT tmp_wide;
603 HOST_WIDE_INT new_wide = tmp_wide*10 + (*p - '0');
604 if (new_wide < tmp_wide)
606 /* Return INT_MAX equiv on overflow. */
607 tmp_wide = (~(unsigned HOST_WIDE_INT)0) >> 1;
615 tmp_wide = -tmp_wide;
620 /* Read an rtx in printed representation from INFILE
621 and return an actual rtx in core constructed accordingly.
622 read_rtx is not used in the compiler proper, but rather in
623 the utilities gen*.c that construct C code from machine descriptions. */
629 register int i, j, list_counter;
631 register char *format_ptr;
632 /* tmp_char is a buffer used for reading decimal integers
633 and names of rtx types and machine modes.
634 Therefore, 256 must be enough. */
639 HOST_WIDE_INT tmp_wide;
641 /* Linked list structure for making RTXs: */
644 struct rtx_list *next;
645 rtx value; /* Value of this node... */
648 c = read_skip_spaces (infile); /* Should be open paren. */
650 dump_and_abort ('(', c, infile);
652 read_name (tmp_char, infile);
656 for (i=0; i < NUM_RTX_CODE; i++) /* @@ might speed this search up */
658 if (!(strcmp (tmp_char, GET_RTX_NAME (i))))
660 tmp_code = (RTX_CODE) i; /* get value for name */
664 if (tmp_code == UNKNOWN)
667 "Unknown rtx read in rtl.read_rtx(). Code name was %s .",
670 /* (NIL) stands for an expression that isn't there. */
673 /* Discard the closeparen. */
674 while ((c = getc (infile)) && c != ')');
678 return_rtx = rtx_alloc (tmp_code); /* if we end up with an insn expression
679 then we free this space below. */
680 format_ptr = GET_RTX_FORMAT (GET_CODE (return_rtx));
682 /* If what follows is `: mode ', read it and
683 store the mode in the rtx. */
685 i = read_skip_spaces (infile);
689 read_name (tmp_char, infile);
690 for (k = 0; k < NUM_MACHINE_MODES; k++)
691 if (!strcmp (GET_MODE_NAME (k), tmp_char))
694 PUT_MODE (return_rtx, (enum machine_mode) k );
699 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (return_rtx)); i++)
700 switch (*format_ptr++)
702 /* 0 means a field for internal use only.
703 Don't expect it to be present in the input. */
709 XEXP (return_rtx, i) = read_rtx (infile);
713 /* 'V' is an optional vector: if a closeparen follows,
714 just store NULL for this element. */
715 c = read_skip_spaces (infile);
719 XVEC (return_rtx, i) = 0;
722 /* Now process the vector. */
726 register struct rtx_list *next_rtx, *rtx_list_link;
727 struct rtx_list *list_rtx = NULL;
729 c = read_skip_spaces (infile);
731 dump_and_abort ('[', c, infile);
733 /* add expressions to a list, while keeping a count */
736 while ((c = read_skip_spaces (infile)) && c != ']')
740 rtx_list_link = (struct rtx_list *)
741 alloca (sizeof (struct rtx_list));
742 rtx_list_link->value = read_rtx (infile);
744 list_rtx = rtx_list_link;
746 next_rtx->next = rtx_list_link;
747 next_rtx = rtx_list_link;
748 rtx_list_link->next = 0;
750 /* get vector length and allocate it */
751 XVEC (return_rtx, i) = (list_counter
752 ? rtvec_alloc (list_counter) : NULL_RTVEC);
753 if (list_counter > 0)
756 for (j = 0; j < list_counter; j++,
757 next_rtx = next_rtx->next)
758 XVECEXP (return_rtx, i, j) = next_rtx->value;
760 /* close bracket gotten */
765 /* 'S' is an optional string: if a closeparen follows,
766 just store NULL for this element. */
767 c = read_skip_spaces (infile);
771 XSTR (return_rtx, i) = 0;
778 register char *stringbuf;
780 c = read_skip_spaces (infile);
784 c = read_skip_spaces (infile);
787 dump_and_abort ('"', c, infile);
791 c = getc (infile); /* Read the string */
794 c = getc (infile); /* Read the string */
795 /* \; makes stuff for a C string constant containing
799 obstack_grow (rtl_obstack, "\\n\\t", 4);
806 obstack_1grow (rtl_obstack, c);
809 obstack_1grow (rtl_obstack, 0);
810 stringbuf = (char *) obstack_finish (rtl_obstack);
814 c = read_skip_spaces (infile);
816 dump_and_abort (')', c, infile);
818 XSTR (return_rtx, i) = stringbuf;
823 read_name (tmp_char, infile);
824 #if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_INT
825 tmp_wide = atoi (tmp_char);
827 #if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONG
828 tmp_wide = atol (tmp_char);
830 /* Prefer atoll over atoq, since the former is in the ISO C9X draft.
831 But prefer not to use our hand-rolled function above either. */
832 #if defined(HAVE_ATOLL) || !defined(HAVE_ATOQ)
833 tmp_wide = atoll (tmp_char);
835 tmp_wide = atoq (tmp_char);
839 XWINT (return_rtx, i) = tmp_wide;
844 read_name (tmp_char, infile);
845 tmp_int = atoi (tmp_char);
846 XINT (return_rtx, i) = tmp_int;
851 "switch format wrong in rtl.read_rtx(). format was: %c.\n",
853 fprintf (stderr, "\tfile position: %ld\n", ftell (infile));
857 c = read_skip_spaces (infile);
859 dump_and_abort (')', c, infile);
864 /* This is called once per compilation, before any rtx's are constructed.
865 It initializes the vector `rtx_length', the extra CC modes, if any,
866 and computes certain commonly-used modes. */
871 int min_class_size[(int) MAX_MODE_CLASS];
872 enum machine_mode mode;
875 for (i = 0; i < NUM_RTX_CODE; i++)
876 rtx_length[i] = strlen (rtx_format[i]);
878 /* Make CONST_DOUBLE bigger, if real values are bigger than
879 it normally expects to have room for.
880 Note that REAL_VALUE_TYPE is not defined by default,
881 since tree.h is not included. But the default dfn as `double'
883 #ifdef REAL_VALUE_TYPE
884 i = sizeof (REAL_VALUE_TYPE) / sizeof (rtunion) + 2;
885 if (rtx_length[(int) CONST_DOUBLE] < i)
887 char *s = (char *) xmalloc (i + 1);
888 rtx_length[(int) CONST_DOUBLE] = i;
889 rtx_format[(int) CONST_DOUBLE] = s;
892 /* Set the GET_RTX_FORMAT of CONST_DOUBLE to a string
893 of as many `w's as we now have elements. Subtract two from
894 the size to account for the 'e' and the '0'. */
895 for (i = 2; i < rtx_length[(int) CONST_DOUBLE]; i++)
901 #ifdef EXTRA_CC_MODES
902 for (i = (int) CCmode + 1; i < (int) MAX_MACHINE_MODE; i++)
904 mode_class[i] = MODE_CC;
905 mode_mask_array[i] = mode_mask_array[(int) CCmode];
906 mode_size[i] = mode_size[(int) CCmode];
907 mode_unit_size[i] = mode_unit_size[(int) CCmode];
908 mode_wider_mode[i - 1] = i;
909 mode_wider_mode[i] = (unsigned char)VOIDmode;
913 /* Find the narrowest mode for each class. */
915 for (i = 0; i < (int) MAX_MODE_CLASS; i++)
916 min_class_size[i] = 1000;
918 for (mode = VOIDmode; (int) mode < (int) MAX_MACHINE_MODE;
919 mode = (enum machine_mode) ((int) mode + 1))
921 if (GET_MODE_SIZE (mode) < min_class_size[(int) GET_MODE_CLASS (mode)])
923 class_narrowest_mode[(int) GET_MODE_CLASS (mode)] = mode;
924 min_class_size[(int) GET_MODE_CLASS (mode)] = GET_MODE_SIZE (mode);