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. */
28 #define obstack_chunk_alloc xmalloc
29 #define obstack_chunk_free free
31 /* Obstack used for allocating RTL objects.
32 Between functions, this is the permanent_obstack.
33 While parsing and expanding a function, this is maybepermanent_obstack
34 so we can save it if it is an inline function.
35 During optimization and output, this is function_obstack. */
37 extern struct obstack *rtl_obstack;
39 #ifdef NEED_DECLARATION_ATOL
43 /* Indexed by rtx code, gives number of operands for an rtx with that code.
44 Does NOT include rtx header data (code and links).
45 This array is initialized in init_rtl. */
47 int rtx_length[NUM_RTX_CODE + 1];
49 /* Indexed by rtx code, gives the name of that kind of rtx, as a C string. */
51 #define DEF_RTL_EXPR(ENUM, NAME, FORMAT, CLASS) NAME ,
54 #include "rtl.def" /* rtl expressions are documented here */
59 /* Indexed by machine mode, gives the name of that machine mode.
60 This name does not include the letters "mode". */
62 #define DEF_MACHMODE(SYM, NAME, CLASS, SIZE, UNIT, WIDER) NAME,
64 char *mode_name[(int) MAX_MACHINE_MODE] = {
65 #include "machmode.def"
75 /* Indexed by machine mode, gives the length of the mode, in bytes.
76 GET_MODE_CLASS uses this. */
78 #define DEF_MACHMODE(SYM, NAME, CLASS, SIZE, UNIT, WIDER) CLASS,
80 enum mode_class mode_class[(int) MAX_MACHINE_MODE] = {
81 #include "machmode.def"
86 /* Indexed by machine mode, gives the length of the mode, in bytes.
87 GET_MODE_SIZE uses this. */
89 #define DEF_MACHMODE(SYM, NAME, CLASS, SIZE, UNIT, WIDER) SIZE,
91 int mode_size[(int) MAX_MACHINE_MODE] = {
92 #include "machmode.def"
97 /* Indexed by machine mode, gives the length of the mode's subunit.
98 GET_MODE_UNIT_SIZE uses this. */
100 #define DEF_MACHMODE(SYM, NAME, CLASS, SIZE, UNIT, WIDER) UNIT,
102 int mode_unit_size[(int) MAX_MACHINE_MODE] = {
103 #include "machmode.def" /* machine modes are documented here */
108 /* Indexed by machine mode, gives next wider natural mode
109 (QI -> HI -> SI -> DI, etc.) Widening multiply instructions
112 #define DEF_MACHMODE(SYM, NAME, CLASS, SIZE, UNIT, WIDER) \
113 (enum machine_mode) WIDER,
115 enum machine_mode mode_wider_mode[(int) MAX_MACHINE_MODE] = {
116 #include "machmode.def" /* machine modes are documented here */
121 /* Indexed by mode class, gives the narrowest mode for each class. */
123 enum machine_mode class_narrowest_mode[(int) MAX_MODE_CLASS];
125 /* Indexed by rtx code, gives a sequence of operand-types for
126 rtx's of that code. The sequence is a C string in which
127 each character describes one operand. */
129 char *rtx_format[] = {
131 can cause a warning message
132 "0" field is unused (or used in a phase-dependent manner)
136 "n" like "i", but prints entries from `note_insn_name'
137 "w" an integer of width HOST_BITS_PER_WIDE_INT
139 "s" a pointer to a string
141 "S" like "s", but optional:
142 the containing rtx may end before this operand
143 "e" a pointer to an rtl expression
144 prints the expression
145 "E" a pointer to a vector that points to a number of rtl expressions
146 prints a list of the rtl expressions
147 "V" like "E", but optional:
148 the containing rtx may end before this operand
149 "u" a pointer to another insn
150 prints the uid of the insn. */
152 #define DEF_RTL_EXPR(ENUM, NAME, FORMAT, CLASS) FORMAT ,
153 #include "rtl.def" /* rtl expressions are defined here */
157 /* Indexed by rtx code, gives a character representing the "class" of
158 that rtx code. See rtl.def for documentation on the defined classes. */
161 #define DEF_RTL_EXPR(ENUM, NAME, FORMAT, CLASS) CLASS,
162 #include "rtl.def" /* rtl expressions are defined here */
166 /* Names for kinds of NOTEs and REG_NOTEs. */
168 char *note_insn_name[] = { 0 , "NOTE_INSN_DELETED",
169 "NOTE_INSN_BLOCK_BEG", "NOTE_INSN_BLOCK_END",
170 "NOTE_INSN_LOOP_BEG", "NOTE_INSN_LOOP_END",
171 "NOTE_INSN_FUNCTION_END", "NOTE_INSN_SETJMP",
172 "NOTE_INSN_LOOP_CONT", "NOTE_INSN_LOOP_VTOP",
173 "NOTE_INSN_PROLOGUE_END", "NOTE_INSN_EPILOGUE_BEG",
174 "NOTE_INSN_DELETED_LABEL", "NOTE_INSN_FUNCTION_BEG",
175 "NOTE_INSN_EH_REGION_BEG", "NOTE_INSN_EH_REGION_END",
176 "NOTE_REPEATED_LINE_NUMBER" };
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" };
186 static void dump_and_abort PROTO((int, int, FILE *));
187 static void read_name PROTO((char *, FILE *));
189 /* Allocate an rtx vector of N elements.
190 Store the length, and initialize all elements to zero. */
199 rt = (rtvec) obstack_alloc (rtl_obstack,
200 sizeof (struct rtvec_def)
201 + (( n - 1) * sizeof (rtunion)));
203 /* clear out the vector */
204 PUT_NUM_ELEM (rt, n);
206 for (i = 0; i < n; i++)
207 rt->elem[i].rtwint = 0;
212 /* Allocate an rtx of code CODE. The CODE is stored in the rtx;
213 all the rest is initialized to zero. */
220 register struct obstack *ob = rtl_obstack;
221 register int nelts = GET_RTX_LENGTH (code);
222 register int length = sizeof (struct rtx_def)
223 + (nelts - 1) * sizeof (rtunion);
225 /* This function is called more than any other in GCC,
226 so we manipulate the obstack directly.
228 Even though rtx objects are word aligned, we may be sharing an obstack
229 with tree nodes, which may have to be double-word aligned. So align
230 our length to the alignment mask in the obstack. */
232 length = (length + ob->alignment_mask) & ~ ob->alignment_mask;
234 if (ob->chunk_limit - ob->next_free < length)
235 _obstack_newchunk (ob, length);
236 rt = (rtx)ob->object_base;
237 ob->next_free += length;
238 ob->object_base = ob->next_free;
240 /* We want to clear everything up to the FLD array. Normally, this is
241 one int, but we don't want to assume that and it isn't very portable
244 length = (sizeof (struct rtx_def) - sizeof (rtunion) - 1) / sizeof (int);
245 for (; length >= 0; length--)
246 ((int *) rt)[length] = 0;
253 /* Free the rtx X and all RTL allocated since X. */
259 obstack_free (rtl_obstack, x);
262 /* Create a new copy of an rtx.
263 Recursively copies the operands of the rtx,
264 except for those few rtx codes that are sharable. */
272 register RTX_CODE code;
273 register char *format_ptr;
275 code = GET_CODE (orig);
288 /* SCRATCH must be shared because they represent distinct values. */
293 /* CONST can be shared if it contains a SYMBOL_REF. If it contains
294 a LABEL_REF, it isn't sharable. */
295 if (GET_CODE (XEXP (orig, 0)) == PLUS
296 && GET_CODE (XEXP (XEXP (orig, 0), 0)) == SYMBOL_REF
297 && GET_CODE (XEXP (XEXP (orig, 0), 1)) == CONST_INT)
301 /* A MEM with a constant address is not sharable. The problem is that
302 the constant address may need to be reloaded. If the mem is shared,
303 then reloading one copy of this mem will cause all copies to appear
304 to have been reloaded. */
310 copy = rtx_alloc (code);
311 PUT_MODE (copy, GET_MODE (orig));
312 copy->in_struct = orig->in_struct;
313 copy->volatil = orig->volatil;
314 copy->unchanging = orig->unchanging;
315 copy->integrated = orig->integrated;
317 format_ptr = GET_RTX_FORMAT (GET_CODE (copy));
319 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (copy)); i++)
321 switch (*format_ptr++)
324 XEXP (copy, i) = XEXP (orig, i);
325 if (XEXP (orig, i) != NULL)
326 XEXP (copy, i) = copy_rtx (XEXP (orig, i));
331 XEXP (copy, i) = XEXP (orig, i);
336 XVEC (copy, i) = XVEC (orig, i);
337 if (XVEC (orig, i) != NULL)
339 XVEC (copy, i) = rtvec_alloc (XVECLEN (orig, i));
340 for (j = 0; j < XVECLEN (copy, i); j++)
341 XVECEXP (copy, i, j) = copy_rtx (XVECEXP (orig, i, j));
346 XWINT (copy, i) = XWINT (orig, i);
350 XINT (copy, i) = XINT (orig, i);
355 XSTR (copy, i) = XSTR (orig, i);
365 /* Similar to `copy_rtx' except that if MAY_SHARE is present, it is
366 placed in the result directly, rather than being copied. */
369 copy_most_rtx (orig, may_share)
371 register rtx may_share;
375 register RTX_CODE code;
376 register char *format_ptr;
378 if (orig == may_share)
381 code = GET_CODE (orig);
398 copy = rtx_alloc (code);
399 PUT_MODE (copy, GET_MODE (orig));
400 copy->in_struct = orig->in_struct;
401 copy->volatil = orig->volatil;
402 copy->unchanging = orig->unchanging;
403 copy->integrated = orig->integrated;
405 format_ptr = GET_RTX_FORMAT (GET_CODE (copy));
407 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (copy)); i++)
409 switch (*format_ptr++)
412 XEXP (copy, i) = XEXP (orig, i);
413 if (XEXP (orig, i) != NULL && XEXP (orig, i) != may_share)
414 XEXP (copy, i) = copy_most_rtx (XEXP (orig, i), may_share);
419 XEXP (copy, i) = XEXP (orig, i);
424 XVEC (copy, i) = XVEC (orig, i);
425 if (XVEC (orig, i) != NULL)
427 XVEC (copy, i) = rtvec_alloc (XVECLEN (orig, i));
428 for (j = 0; j < XVECLEN (copy, i); j++)
430 = copy_most_rtx (XVECEXP (orig, i, j), may_share);
435 XWINT (copy, i) = XWINT (orig, i);
440 XINT (copy, i) = XINT (orig, i);
445 XSTR (copy, i) = XSTR (orig, i);
455 /* Subroutines of read_rtx. */
457 /* Dump code after printing a message. Used when read_rtx finds
461 dump_and_abort (expected_c, actual_c, infile)
462 int expected_c, actual_c;
469 "Expected character %c. Found character %c.",
470 expected_c, actual_c);
471 fprintf (stderr, " At file position: %ld\n", ftell (infile));
472 fprintf (stderr, "Following characters are:\n\t");
473 for (i = 0; i < 200; i++)
479 fprintf (stderr, "Aborting.\n");
483 /* Read chars from INFILE until a non-whitespace char
484 and return that. Comments, both Lisp style and C style,
485 are treated as whitespace.
486 Tools such as genflags use this function. */
489 read_skip_spaces (infile)
493 while ((c = getc (infile)))
495 if (c == ' ' || c == '\n' || c == '\t' || c == '\f')
499 while ((c = getc (infile)) && c != '\n' && c != EOF)
507 dump_and_abort ('*', c, infile);
510 while ((c = getc (infile)) && c != EOF)
512 if (prevc == '*' && c == '/')
522 /* Read an rtx code name into the buffer STR[].
523 It is terminated by any of the punctuation chars of rtx printed syntax. */
526 read_name (str, infile)
533 c = read_skip_spaces(infile);
538 if (c == ' ' || c == '\n' || c == '\t' || c == '\f')
540 if (c == ':' || c == ')' || c == ']' || c == '"' || c == '/'
541 || c == '(' || c == '[')
551 fprintf (stderr, "missing name or number");
552 dump_and_abort (-1, -1, infile);
558 /* Provide a version of a function to read a long long if the system does
560 #if HOST_BITS_PER_WIDE_INT > HOST_BITS_PER_LONG && !defined(HAVE_ATOLL) && !defined(HAVE_ATOQ)
566 HOST_WIDE_INT tmp_wide;
578 HOST_WIDE_INT new_wide = tmp_wide*10 + (*p - '0');
579 if (new_wide < tmp_wide)
581 /* Return INT_MAX equiv on overflow. */
582 tmp_wide = (~(unsigned HOST_WIDE_INT)0) >> 1;
590 tmp_wide = -tmp_wide;
595 /* Read an rtx in printed representation from INFILE
596 and return an actual rtx in core constructed accordingly.
597 read_rtx is not used in the compiler proper, but rather in
598 the utilities gen*.c that construct C code from machine descriptions. */
604 register int i, j, list_counter;
606 register char *format_ptr;
607 /* tmp_char is a buffer used for reading decimal integers
608 and names of rtx types and machine modes.
609 Therefore, 256 must be enough. */
614 HOST_WIDE_INT tmp_wide;
616 /* Linked list structure for making RTXs: */
619 struct rtx_list *next;
620 rtx value; /* Value of this node... */
623 c = read_skip_spaces (infile); /* Should be open paren. */
625 dump_and_abort ('(', c, infile);
627 read_name (tmp_char, infile);
631 for (i=0; i < NUM_RTX_CODE; i++) /* @@ might speed this search up */
633 if (!(strcmp (tmp_char, GET_RTX_NAME (i))))
635 tmp_code = (RTX_CODE) i; /* get value for name */
639 if (tmp_code == UNKNOWN)
642 "Unknown rtx read in rtl.read_rtx(). Code name was %s .",
645 /* (NIL) stands for an expression that isn't there. */
648 /* Discard the closeparen. */
649 while ((c = getc (infile)) && c != ')');
653 return_rtx = rtx_alloc (tmp_code); /* if we end up with an insn expression
654 then we free this space below. */
655 format_ptr = GET_RTX_FORMAT (GET_CODE (return_rtx));
657 /* If what follows is `: mode ', read it and
658 store the mode in the rtx. */
660 i = read_skip_spaces (infile);
664 read_name (tmp_char, infile);
665 for (k = 0; k < NUM_MACHINE_MODES; k++)
666 if (!strcmp (GET_MODE_NAME (k), tmp_char))
669 PUT_MODE (return_rtx, (enum machine_mode) k );
674 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (return_rtx)); i++)
675 switch (*format_ptr++)
677 /* 0 means a field for internal use only.
678 Don't expect it to be present in the input. */
684 XEXP (return_rtx, i) = read_rtx (infile);
688 /* 'V' is an optional vector: if a closeparen follows,
689 just store NULL for this element. */
690 c = read_skip_spaces (infile);
694 XVEC (return_rtx, i) = 0;
697 /* Now process the vector. */
701 register struct rtx_list *next_rtx, *rtx_list_link;
702 struct rtx_list *list_rtx = NULL;
704 c = read_skip_spaces (infile);
706 dump_and_abort ('[', c, infile);
708 /* add expressions to a list, while keeping a count */
711 while ((c = read_skip_spaces (infile)) && c != ']')
715 rtx_list_link = (struct rtx_list *)
716 alloca (sizeof (struct rtx_list));
717 rtx_list_link->value = read_rtx (infile);
719 list_rtx = rtx_list_link;
721 next_rtx->next = rtx_list_link;
722 next_rtx = rtx_list_link;
723 rtx_list_link->next = 0;
725 /* get vector length and allocate it */
726 XVEC (return_rtx, i) = (list_counter
727 ? rtvec_alloc (list_counter) : NULL_RTVEC);
728 if (list_counter > 0)
731 for (j = 0; j < list_counter; j++,
732 next_rtx = next_rtx->next)
733 XVECEXP (return_rtx, i, j) = next_rtx->value;
735 /* close bracket gotten */
740 /* 'S' is an optional string: if a closeparen follows,
741 just store NULL for this element. */
742 c = read_skip_spaces (infile);
746 XSTR (return_rtx, i) = 0;
753 register char *stringbuf;
755 c = read_skip_spaces (infile);
759 c = read_skip_spaces (infile);
762 dump_and_abort ('"', c, infile);
766 c = getc (infile); /* Read the string */
769 c = getc (infile); /* Read the string */
770 /* \; makes stuff for a C string constant containing
774 obstack_grow (rtl_obstack, "\\n\\t", 4);
781 obstack_1grow (rtl_obstack, c);
784 obstack_1grow (rtl_obstack, 0);
785 stringbuf = (char *) obstack_finish (rtl_obstack);
789 c = read_skip_spaces (infile);
791 dump_and_abort (')', c, infile);
793 XSTR (return_rtx, i) = stringbuf;
798 read_name (tmp_char, infile);
799 #if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_INT
800 tmp_wide = atoi (tmp_char);
802 #if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONG
803 tmp_wide = atol (tmp_char);
805 /* Prefer atoll over atoq, since the former is in the ISO C9X draft.
806 But prefer not to use our hand-rolled function above either. */
807 #if defined(HAVE_ATOLL) || !defined(HAVE_ATOQ)
808 tmp_wide = atoll (tmp_char);
810 tmp_wide = atoq (tmp_char);
814 XWINT (return_rtx, i) = tmp_wide;
819 read_name (tmp_char, infile);
820 tmp_int = atoi (tmp_char);
821 XINT (return_rtx, i) = tmp_int;
826 "switch format wrong in rtl.read_rtx(). format was: %c.\n",
828 fprintf (stderr, "\tfile position: %ld\n", ftell (infile));
832 c = read_skip_spaces (infile);
834 dump_and_abort (')', c, infile);
839 /* This is called once per compilation, before any rtx's are constructed.
840 It initializes the vector `rtx_length', the extra CC modes, if any,
841 and computes certain commonly-used modes. */
846 int min_class_size[(int) MAX_MODE_CLASS];
847 enum machine_mode mode;
850 for (i = 0; i < NUM_RTX_CODE; i++)
851 rtx_length[i] = strlen (rtx_format[i]);
853 /* Make CONST_DOUBLE bigger, if real values are bigger than
854 it normally expects to have room for.
855 Note that REAL_VALUE_TYPE is not defined by default,
856 since tree.h is not included. But the default dfn as `double'
858 #ifdef REAL_VALUE_TYPE
859 i = sizeof (REAL_VALUE_TYPE) / sizeof (rtunion) + 2;
860 if (rtx_length[(int) CONST_DOUBLE] < i)
862 char *s = (char *) xmalloc (i + 1);
863 rtx_length[(int) CONST_DOUBLE] = i;
864 rtx_format[(int) CONST_DOUBLE] = s;
867 /* Set the GET_RTX_FORMAT of CONST_DOUBLE to a string
868 of as many `w's as we now have elements. Subtract two from
869 the size to account for the 'e' and the '0'. */
870 for (i = 2; i < rtx_length[(int) CONST_DOUBLE]; i++)
876 #ifdef EXTRA_CC_MODES
877 for (i = (int) CCmode + 1; i < (int) MAX_MACHINE_MODE; i++)
879 mode_class[i] = MODE_CC;
880 mode_size[i] = mode_size[(int) CCmode];
881 mode_unit_size[i] = mode_unit_size[(int) CCmode];
882 mode_wider_mode[i - 1] = (enum machine_mode) i;
883 mode_wider_mode[i] = VOIDmode;
887 /* Find the narrowest mode for each class. */
889 for (i = 0; i < (int) MAX_MODE_CLASS; i++)
890 min_class_size[i] = 1000;
892 for (mode = VOIDmode; (int) mode < (int) MAX_MACHINE_MODE;
893 mode = (enum machine_mode) ((int) mode + 1))
895 if (GET_MODE_SIZE (mode) < min_class_size[(int) GET_MODE_CLASS (mode)])
897 class_narrowest_mode[(int) GET_MODE_CLASS (mode)] = mode;
898 min_class_size[(int) GET_MODE_CLASS (mode)] = GET_MODE_SIZE (mode);