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] = {
62 #include "machmode.def"
72 /* Indexed by machine mode, gives the length of the mode, in bytes.
73 GET_MODE_CLASS uses this. */
75 #define DEF_MACHMODE(SYM, NAME, CLASS, SIZE, UNIT, WIDER) CLASS,
77 enum mode_class mode_class[(int) MAX_MACHINE_MODE] = {
78 #include "machmode.def"
83 /* Indexed by machine mode, gives the length of the mode, in bytes.
84 GET_MODE_SIZE uses this. */
86 #define DEF_MACHMODE(SYM, NAME, CLASS, SIZE, UNIT, WIDER) SIZE,
88 int mode_size[(int) MAX_MACHINE_MODE] = {
89 #include "machmode.def"
94 /* Indexed by machine mode, gives the length of the mode's subunit.
95 GET_MODE_UNIT_SIZE uses this. */
97 #define DEF_MACHMODE(SYM, NAME, CLASS, SIZE, UNIT, WIDER) UNIT,
99 int mode_unit_size[(int) MAX_MACHINE_MODE] = {
100 #include "machmode.def" /* machine modes are documented here */
105 /* Indexed by machine mode, gives next wider natural mode
106 (QI -> HI -> SI -> DI, etc.) Widening multiply instructions
109 #define DEF_MACHMODE(SYM, NAME, CLASS, SIZE, UNIT, WIDER) \
110 (enum machine_mode) WIDER,
112 enum machine_mode mode_wider_mode[(int) MAX_MACHINE_MODE] = {
113 #include "machmode.def" /* machine modes are documented here */
118 /* Indexed by mode class, gives the narrowest mode for each class. */
120 enum machine_mode class_narrowest_mode[(int) MAX_MODE_CLASS];
122 /* Indexed by rtx code, gives a sequence of operand-types for
123 rtx's of that code. The sequence is a C string in which
124 each character describes one operand. */
126 char *rtx_format[] = {
128 can cause a warning message
129 "0" field is unused (or used in a phase-dependent manner)
133 "n" like "i", but prints entries from `note_insn_name'
134 "w" an integer of width HOST_BITS_PER_WIDE_INT
136 "s" a pointer to a string
138 "S" like "s", but optional:
139 the containing rtx may end before this operand
140 "e" a pointer to an rtl expression
141 prints the expression
142 "E" a pointer to a vector that points to a number of rtl expressions
143 prints a list of the rtl expressions
144 "V" like "E", but optional:
145 the containing rtx may end before this operand
146 "u" a pointer to another insn
147 prints the uid of the insn.
148 "b" is a pointer to a bitmap header.
149 "t" is a tree pointer. */
151 #define DEF_RTL_EXPR(ENUM, NAME, FORMAT, CLASS) FORMAT ,
152 #include "rtl.def" /* rtl expressions are defined here */
156 /* Indexed by rtx code, gives a character representing the "class" of
157 that rtx code. See rtl.def for documentation on the defined classes. */
160 #define DEF_RTL_EXPR(ENUM, NAME, FORMAT, CLASS) CLASS,
161 #include "rtl.def" /* rtl expressions are defined here */
165 /* Names for kinds of NOTEs and REG_NOTEs. */
167 char *note_insn_name[] = { 0 , "NOTE_INSN_DELETED",
168 "NOTE_INSN_BLOCK_BEG", "NOTE_INSN_BLOCK_END",
169 "NOTE_INSN_LOOP_BEG", "NOTE_INSN_LOOP_END",
170 "NOTE_INSN_FUNCTION_END", "NOTE_INSN_SETJMP",
171 "NOTE_INSN_LOOP_CONT", "NOTE_INSN_LOOP_VTOP",
172 "NOTE_INSN_PROLOGUE_END", "NOTE_INSN_EPILOGUE_BEG",
173 "NOTE_INSN_DELETED_LABEL", "NOTE_INSN_FUNCTION_BEG",
174 "NOTE_INSN_EH_REGION_BEG", "NOTE_INSN_EH_REGION_END",
175 "NOTE_REPEATED_LINE_NUMBER", "NOTE_INSN_RANGE_START",
176 "NOTE_INSN_RANGE_END", "NOTE_INSN_LIVE" };
178 char *reg_note_name[] = { "", "REG_DEAD", "REG_INC", "REG_EQUIV", "REG_WAS_0",
179 "REG_EQUAL", "REG_RETVAL", "REG_LIBCALL",
180 "REG_NONNEG", "REG_NO_CONFLICT", "REG_UNUSED",
181 "REG_CC_SETTER", "REG_CC_USER", "REG_LABEL",
182 "REG_DEP_ANTI", "REG_DEP_OUTPUT", "REG_BR_PROB",
183 "REG_EXEC_COUNT", "REG_NOALIAS", "REG_SAVE_AREA",
184 "REG_BR_PRED", "REG_EH_CONTEXT",
185 "REG_FRAME_RELATED_EXPR" };
187 static void dump_and_abort PROTO((int, int, FILE *));
188 static void read_name PROTO((char *, FILE *));
190 /* Allocate an rtx vector of N elements.
191 Store the length, and initialize all elements to zero. */
200 rt = (rtvec) obstack_alloc (rtl_obstack,
201 sizeof (struct rtvec_def)
202 + (( n - 1) * sizeof (rtunion)));
204 /* clear out the vector */
205 PUT_NUM_ELEM (rt, n);
207 for (i = 0; i < n; i++)
208 rt->elem[i].rtwint = 0;
213 /* Allocate an rtx of code CODE. The CODE is stored in the rtx;
214 all the rest is initialized to zero. */
221 register struct obstack *ob = rtl_obstack;
222 register int nelts = GET_RTX_LENGTH (code);
223 register int length = sizeof (struct rtx_def)
224 + (nelts - 1) * sizeof (rtunion);
226 /* This function is called more than any other in GCC,
227 so we manipulate the obstack directly.
229 Even though rtx objects are word aligned, we may be sharing an obstack
230 with tree nodes, which may have to be double-word aligned. So align
231 our length to the alignment mask in the obstack. */
233 length = (length + ob->alignment_mask) & ~ ob->alignment_mask;
235 if (ob->chunk_limit - ob->next_free < length)
236 _obstack_newchunk (ob, length);
237 rt = (rtx)ob->object_base;
238 ob->next_free += length;
239 ob->object_base = ob->next_free;
241 /* We want to clear everything up to the FLD array. Normally, this is
242 one int, but we don't want to assume that and it isn't very portable
245 length = (sizeof (struct rtx_def) - sizeof (rtunion) - 1) / sizeof (int);
246 for (; length >= 0; length--)
247 ((int *) rt)[length] = 0;
254 /* Free the rtx X and all RTL allocated since X. */
260 obstack_free (rtl_obstack, x);
263 /* Create a new copy of an rtx.
264 Recursively copies the operands of the rtx,
265 except for those few rtx codes that are sharable. */
273 register RTX_CODE code;
274 register char *format_ptr;
276 code = GET_CODE (orig);
289 /* SCRATCH must be shared because they represent distinct values. */
294 /* CONST can be shared if it contains a SYMBOL_REF. If it contains
295 a LABEL_REF, it isn't sharable. */
296 if (GET_CODE (XEXP (orig, 0)) == PLUS
297 && GET_CODE (XEXP (XEXP (orig, 0), 0)) == SYMBOL_REF
298 && GET_CODE (XEXP (XEXP (orig, 0), 1)) == CONST_INT)
302 /* A MEM with a constant address is not sharable. The problem is that
303 the constant address may need to be reloaded. If the mem is shared,
304 then reloading one copy of this mem will cause all copies to appear
305 to have been reloaded. */
311 copy = rtx_alloc (code);
312 PUT_MODE (copy, GET_MODE (orig));
313 copy->in_struct = orig->in_struct;
314 copy->volatil = orig->volatil;
315 copy->unchanging = orig->unchanging;
316 copy->integrated = orig->integrated;
318 format_ptr = GET_RTX_FORMAT (GET_CODE (copy));
320 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (copy)); i++)
322 switch (*format_ptr++)
325 XEXP (copy, i) = XEXP (orig, i);
326 if (XEXP (orig, i) != NULL)
327 XEXP (copy, i) = copy_rtx (XEXP (orig, i));
332 XEXP (copy, i) = XEXP (orig, i);
337 XVEC (copy, i) = XVEC (orig, i);
338 if (XVEC (orig, i) != NULL)
340 XVEC (copy, i) = rtvec_alloc (XVECLEN (orig, i));
341 for (j = 0; j < XVECLEN (copy, i); j++)
342 XVECEXP (copy, i, j) = copy_rtx (XVECEXP (orig, i, j));
348 bitmap new_bits = BITMAP_OBSTACK_ALLOC (rtl_obstack);
349 bitmap_copy (new_bits, XBITMAP (orig, i));
350 XBITMAP (copy, i) = new_bits;
355 XTREE (copy, i) = XTREE (orig, i);
359 XWINT (copy, i) = XWINT (orig, i);
363 XINT (copy, i) = XINT (orig, i);
368 XSTR (copy, i) = XSTR (orig, i);
378 /* Similar to `copy_rtx' except that if MAY_SHARE is present, it is
379 placed in the result directly, rather than being copied. */
382 copy_most_rtx (orig, may_share)
384 register rtx may_share;
388 register RTX_CODE code;
389 register char *format_ptr;
391 if (orig == may_share)
394 code = GET_CODE (orig);
411 copy = rtx_alloc (code);
412 PUT_MODE (copy, GET_MODE (orig));
413 copy->in_struct = orig->in_struct;
414 copy->volatil = orig->volatil;
415 copy->unchanging = orig->unchanging;
416 copy->integrated = orig->integrated;
418 format_ptr = GET_RTX_FORMAT (GET_CODE (copy));
420 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (copy)); i++)
422 switch (*format_ptr++)
425 XEXP (copy, i) = XEXP (orig, i);
426 if (XEXP (orig, i) != NULL && XEXP (orig, i) != may_share)
427 XEXP (copy, i) = copy_most_rtx (XEXP (orig, i), may_share);
432 XEXP (copy, i) = XEXP (orig, i);
437 XVEC (copy, i) = XVEC (orig, i);
438 if (XVEC (orig, i) != NULL)
440 XVEC (copy, i) = rtvec_alloc (XVECLEN (orig, i));
441 for (j = 0; j < XVECLEN (copy, i); j++)
443 = copy_most_rtx (XVECEXP (orig, i, j), may_share);
448 XWINT (copy, i) = XWINT (orig, i);
453 XINT (copy, i) = XINT (orig, i);
458 XSTR (copy, i) = XSTR (orig, i);
468 /* Subroutines of read_rtx. */
470 /* Dump code after printing a message. Used when read_rtx finds
474 dump_and_abort (expected_c, actual_c, infile)
475 int expected_c, actual_c;
482 "Expected character %c. Found character %c.",
483 expected_c, actual_c);
484 fprintf (stderr, " At file position: %ld\n", ftell (infile));
485 fprintf (stderr, "Following characters are:\n\t");
486 for (i = 0; i < 200; i++)
492 fprintf (stderr, "Aborting.\n");
496 /* Read chars from INFILE until a non-whitespace char
497 and return that. Comments, both Lisp style and C style,
498 are treated as whitespace.
499 Tools such as genflags use this function. */
502 read_skip_spaces (infile)
506 while ((c = getc (infile)))
508 if (c == ' ' || c == '\n' || c == '\t' || c == '\f')
512 while ((c = getc (infile)) && c != '\n' && c != EOF)
520 dump_and_abort ('*', c, infile);
523 while ((c = getc (infile)) && c != EOF)
525 if (prevc == '*' && c == '/')
535 /* Read an rtx code name into the buffer STR[].
536 It is terminated by any of the punctuation chars of rtx printed syntax. */
539 read_name (str, infile)
546 c = read_skip_spaces(infile);
551 if (c == ' ' || c == '\n' || c == '\t' || c == '\f')
553 if (c == ':' || c == ')' || c == ']' || c == '"' || c == '/'
554 || c == '(' || c == '[')
564 fprintf (stderr, "missing name or number");
565 dump_and_abort (-1, -1, infile);
571 /* Provide a version of a function to read a long long if the system does
573 #if HOST_BITS_PER_WIDE_INT > HOST_BITS_PER_LONG && !defined(HAVE_ATOLL) && !defined(HAVE_ATOQ)
579 HOST_WIDE_INT tmp_wide;
591 HOST_WIDE_INT new_wide = tmp_wide*10 + (*p - '0');
592 if (new_wide < tmp_wide)
594 /* Return INT_MAX equiv on overflow. */
595 tmp_wide = (~(unsigned HOST_WIDE_INT)0) >> 1;
603 tmp_wide = -tmp_wide;
608 /* Read an rtx in printed representation from INFILE
609 and return an actual rtx in core constructed accordingly.
610 read_rtx is not used in the compiler proper, but rather in
611 the utilities gen*.c that construct C code from machine descriptions. */
617 register int i, j, list_counter;
619 register char *format_ptr;
620 /* tmp_char is a buffer used for reading decimal integers
621 and names of rtx types and machine modes.
622 Therefore, 256 must be enough. */
627 HOST_WIDE_INT tmp_wide;
629 /* Linked list structure for making RTXs: */
632 struct rtx_list *next;
633 rtx value; /* Value of this node... */
636 c = read_skip_spaces (infile); /* Should be open paren. */
638 dump_and_abort ('(', c, infile);
640 read_name (tmp_char, infile);
644 for (i=0; i < NUM_RTX_CODE; i++) /* @@ might speed this search up */
646 if (!(strcmp (tmp_char, GET_RTX_NAME (i))))
648 tmp_code = (RTX_CODE) i; /* get value for name */
652 if (tmp_code == UNKNOWN)
655 "Unknown rtx read in rtl.read_rtx(). Code name was %s .",
658 /* (NIL) stands for an expression that isn't there. */
661 /* Discard the closeparen. */
662 while ((c = getc (infile)) && c != ')');
666 return_rtx = rtx_alloc (tmp_code); /* if we end up with an insn expression
667 then we free this space below. */
668 format_ptr = GET_RTX_FORMAT (GET_CODE (return_rtx));
670 /* If what follows is `: mode ', read it and
671 store the mode in the rtx. */
673 i = read_skip_spaces (infile);
677 read_name (tmp_char, infile);
678 for (k = 0; k < NUM_MACHINE_MODES; k++)
679 if (!strcmp (GET_MODE_NAME (k), tmp_char))
682 PUT_MODE (return_rtx, (enum machine_mode) k );
687 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (return_rtx)); i++)
688 switch (*format_ptr++)
690 /* 0 means a field for internal use only.
691 Don't expect it to be present in the input. */
697 XEXP (return_rtx, i) = read_rtx (infile);
701 /* 'V' is an optional vector: if a closeparen follows,
702 just store NULL for this element. */
703 c = read_skip_spaces (infile);
707 XVEC (return_rtx, i) = 0;
710 /* Now process the vector. */
714 register struct rtx_list *next_rtx, *rtx_list_link;
715 struct rtx_list *list_rtx = NULL;
717 c = read_skip_spaces (infile);
719 dump_and_abort ('[', c, infile);
721 /* add expressions to a list, while keeping a count */
724 while ((c = read_skip_spaces (infile)) && c != ']')
728 rtx_list_link = (struct rtx_list *)
729 alloca (sizeof (struct rtx_list));
730 rtx_list_link->value = read_rtx (infile);
732 list_rtx = rtx_list_link;
734 next_rtx->next = rtx_list_link;
735 next_rtx = rtx_list_link;
736 rtx_list_link->next = 0;
738 /* get vector length and allocate it */
739 XVEC (return_rtx, i) = (list_counter
740 ? rtvec_alloc (list_counter) : NULL_RTVEC);
741 if (list_counter > 0)
744 for (j = 0; j < list_counter; j++,
745 next_rtx = next_rtx->next)
746 XVECEXP (return_rtx, i, j) = next_rtx->value;
748 /* close bracket gotten */
753 /* 'S' is an optional string: if a closeparen follows,
754 just store NULL for this element. */
755 c = read_skip_spaces (infile);
759 XSTR (return_rtx, i) = 0;
766 register char *stringbuf;
768 c = read_skip_spaces (infile);
772 c = read_skip_spaces (infile);
775 dump_and_abort ('"', c, infile);
779 c = getc (infile); /* Read the string */
782 c = getc (infile); /* Read the string */
783 /* \; makes stuff for a C string constant containing
787 obstack_grow (rtl_obstack, "\\n\\t", 4);
794 obstack_1grow (rtl_obstack, c);
797 obstack_1grow (rtl_obstack, 0);
798 stringbuf = (char *) obstack_finish (rtl_obstack);
802 c = read_skip_spaces (infile);
804 dump_and_abort (')', c, infile);
806 XSTR (return_rtx, i) = stringbuf;
811 read_name (tmp_char, infile);
812 #if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_INT
813 tmp_wide = atoi (tmp_char);
815 #if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONG
816 tmp_wide = atol (tmp_char);
818 /* Prefer atoll over atoq, since the former is in the ISO C9X draft.
819 But prefer not to use our hand-rolled function above either. */
820 #if defined(HAVE_ATOLL) || !defined(HAVE_ATOQ)
821 tmp_wide = atoll (tmp_char);
823 tmp_wide = atoq (tmp_char);
827 XWINT (return_rtx, i) = tmp_wide;
832 read_name (tmp_char, infile);
833 tmp_int = atoi (tmp_char);
834 XINT (return_rtx, i) = tmp_int;
839 "switch format wrong in rtl.read_rtx(). format was: %c.\n",
841 fprintf (stderr, "\tfile position: %ld\n", ftell (infile));
845 c = read_skip_spaces (infile);
847 dump_and_abort (')', c, infile);
852 /* This is called once per compilation, before any rtx's are constructed.
853 It initializes the vector `rtx_length', the extra CC modes, if any,
854 and computes certain commonly-used modes. */
859 int min_class_size[(int) MAX_MODE_CLASS];
860 enum machine_mode mode;
863 for (i = 0; i < NUM_RTX_CODE; i++)
864 rtx_length[i] = strlen (rtx_format[i]);
866 /* Make CONST_DOUBLE bigger, if real values are bigger than
867 it normally expects to have room for.
868 Note that REAL_VALUE_TYPE is not defined by default,
869 since tree.h is not included. But the default dfn as `double'
871 #ifdef REAL_VALUE_TYPE
872 i = sizeof (REAL_VALUE_TYPE) / sizeof (rtunion) + 2;
873 if (rtx_length[(int) CONST_DOUBLE] < i)
875 char *s = (char *) xmalloc (i + 1);
876 rtx_length[(int) CONST_DOUBLE] = i;
877 rtx_format[(int) CONST_DOUBLE] = s;
880 /* Set the GET_RTX_FORMAT of CONST_DOUBLE to a string
881 of as many `w's as we now have elements. Subtract two from
882 the size to account for the 'e' and the '0'. */
883 for (i = 2; i < rtx_length[(int) CONST_DOUBLE]; i++)
889 #ifdef EXTRA_CC_MODES
890 for (i = (int) CCmode + 1; i < (int) MAX_MACHINE_MODE; i++)
892 mode_class[i] = MODE_CC;
893 mode_size[i] = mode_size[(int) CCmode];
894 mode_unit_size[i] = mode_unit_size[(int) CCmode];
895 mode_wider_mode[i - 1] = (enum machine_mode) i;
896 mode_wider_mode[i] = VOIDmode;
900 /* Find the narrowest mode for each class. */
902 for (i = 0; i < (int) MAX_MODE_CLASS; i++)
903 min_class_size[i] = 1000;
905 for (mode = VOIDmode; (int) mode < (int) MAX_MACHINE_MODE;
906 mode = (enum machine_mode) ((int) mode + 1))
908 if (GET_MODE_SIZE (mode) < min_class_size[(int) GET_MODE_CLASS (mode)])
910 class_narrowest_mode[(int) GET_MODE_CLASS (mode)] = mode;
911 min_class_size[(int) GET_MODE_CLASS (mode)] = GET_MODE_SIZE (mode);