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 #if HOST_BITS_PER_WIDE_INT != HOST_BITS_PER_INT
44 /* Indexed by rtx code, gives number of operands for an rtx with that code.
45 Does NOT include rtx header data (code and links).
46 This array is initialized in init_rtl. */
48 int rtx_length[NUM_RTX_CODE + 1];
50 /* Indexed by rtx code, gives the name of that kind of rtx, as a C string. */
52 #define DEF_RTL_EXPR(ENUM, NAME, FORMAT, CLASS) NAME ,
55 #include "rtl.def" /* rtl expressions are documented here */
60 /* Indexed by machine mode, gives the name of that machine mode.
61 This name does not include the letters "mode". */
63 #define DEF_MACHMODE(SYM, NAME, CLASS, SIZE, UNIT, WIDER) NAME,
65 char *mode_name[(int) MAX_MACHINE_MODE] = {
66 #include "machmode.def"
76 /* Indexed by machine mode, gives the length of the mode, in bytes.
77 GET_MODE_CLASS uses this. */
79 #define DEF_MACHMODE(SYM, NAME, CLASS, SIZE, UNIT, WIDER) CLASS,
81 enum mode_class mode_class[(int) MAX_MACHINE_MODE] = {
82 #include "machmode.def"
87 /* Indexed by machine mode, gives the length of the mode, in bytes.
88 GET_MODE_SIZE uses this. */
90 #define DEF_MACHMODE(SYM, NAME, CLASS, SIZE, UNIT, WIDER) SIZE,
92 int mode_size[(int) MAX_MACHINE_MODE] = {
93 #include "machmode.def"
98 /* Indexed by machine mode, gives the length of the mode's subunit.
99 GET_MODE_UNIT_SIZE uses this. */
101 #define DEF_MACHMODE(SYM, NAME, CLASS, SIZE, UNIT, WIDER) UNIT,
103 int mode_unit_size[(int) MAX_MACHINE_MODE] = {
104 #include "machmode.def" /* machine modes are documented here */
109 /* Indexed by machine mode, gives next wider natural mode
110 (QI -> HI -> SI -> DI, etc.) Widening multiply instructions
113 #define DEF_MACHMODE(SYM, NAME, CLASS, SIZE, UNIT, WIDER) \
114 (enum machine_mode) WIDER,
116 enum machine_mode mode_wider_mode[(int) MAX_MACHINE_MODE] = {
117 #include "machmode.def" /* machine modes are documented here */
122 /* Indexed by mode class, gives the narrowest mode for each class. */
124 enum machine_mode class_narrowest_mode[(int) MAX_MODE_CLASS];
126 /* Indexed by rtx code, gives a sequence of operand-types for
127 rtx's of that code. The sequence is a C string in which
128 each character describes one operand. */
130 char *rtx_format[] = {
132 can cause a warning message
133 "0" field is unused (or used in a phase-dependent manner)
137 "n" like "i", but prints entries from `note_insn_name'
138 "w" an integer of width HOST_BITS_PER_WIDE_INT
140 "s" a pointer to a string
142 "S" like "s", but optional:
143 the containing rtx may end before this operand
144 "e" a pointer to an rtl expression
145 prints the expression
146 "E" a pointer to a vector that points to a number of rtl expressions
147 prints a list of the rtl expressions
148 "V" like "E", but optional:
149 the containing rtx may end before this operand
150 "u" a pointer to another insn
151 prints the uid of the insn. */
153 #define DEF_RTL_EXPR(ENUM, NAME, FORMAT, CLASS) FORMAT ,
154 #include "rtl.def" /* rtl expressions are defined here */
158 /* Indexed by rtx code, gives a character representing the "class" of
159 that rtx code. See rtl.def for documentation on the defined classes. */
162 #define DEF_RTL_EXPR(ENUM, NAME, FORMAT, CLASS) CLASS,
163 #include "rtl.def" /* rtl expressions are defined here */
167 /* Names for kinds of NOTEs and REG_NOTEs. */
169 char *note_insn_name[] = { 0 , "NOTE_INSN_DELETED",
170 "NOTE_INSN_BLOCK_BEG", "NOTE_INSN_BLOCK_END",
171 "NOTE_INSN_LOOP_BEG", "NOTE_INSN_LOOP_END",
172 "NOTE_INSN_FUNCTION_END", "NOTE_INSN_SETJMP",
173 "NOTE_INSN_LOOP_CONT", "NOTE_INSN_LOOP_VTOP",
174 "NOTE_INSN_PROLOGUE_END", "NOTE_INSN_EPILOGUE_BEG",
175 "NOTE_INSN_DELETED_LABEL", "NOTE_INSN_FUNCTION_BEG",
176 "NOTE_INSN_EH_REGION_BEG", "NOTE_INSN_EH_REGION_END",
177 "NOTE_REPEATED_LINE_NUMBER" };
179 char *reg_note_name[] = { "", "REG_DEAD", "REG_INC", "REG_EQUIV", "REG_WAS_0",
180 "REG_EQUAL", "REG_RETVAL", "REG_LIBCALL",
181 "REG_NONNEG", "REG_NO_CONFLICT", "REG_UNUSED",
182 "REG_CC_SETTER", "REG_CC_USER", "REG_LABEL",
183 "REG_DEP_ANTI", "REG_DEP_OUTPUT", "REG_BR_PROB",
184 "REG_EXEC_COUNT", "REG_NOALIAS", "REG_SAVE_AREA",
185 "REG_BR_PRED", "REG_EH_CONTEXT" };
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));
347 XWINT (copy, i) = XWINT (orig, i);
351 XINT (copy, i) = XINT (orig, i);
356 XSTR (copy, i) = XSTR (orig, i);
366 /* Similar to `copy_rtx' except that if MAY_SHARE is present, it is
367 placed in the result directly, rather than being copied. */
370 copy_most_rtx (orig, may_share)
372 register rtx may_share;
376 register RTX_CODE code;
377 register char *format_ptr;
379 if (orig == may_share)
382 code = GET_CODE (orig);
399 copy = rtx_alloc (code);
400 PUT_MODE (copy, GET_MODE (orig));
401 copy->in_struct = orig->in_struct;
402 copy->volatil = orig->volatil;
403 copy->unchanging = orig->unchanging;
404 copy->integrated = orig->integrated;
406 format_ptr = GET_RTX_FORMAT (GET_CODE (copy));
408 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (copy)); i++)
410 switch (*format_ptr++)
413 XEXP (copy, i) = XEXP (orig, i);
414 if (XEXP (orig, i) != NULL && XEXP (orig, i) != may_share)
415 XEXP (copy, i) = copy_most_rtx (XEXP (orig, i), may_share);
420 XEXP (copy, i) = XEXP (orig, i);
425 XVEC (copy, i) = XVEC (orig, i);
426 if (XVEC (orig, i) != NULL)
428 XVEC (copy, i) = rtvec_alloc (XVECLEN (orig, i));
429 for (j = 0; j < XVECLEN (copy, i); j++)
431 = copy_most_rtx (XVECEXP (orig, i, j), may_share);
436 XWINT (copy, i) = XWINT (orig, i);
441 XINT (copy, i) = XINT (orig, i);
446 XSTR (copy, i) = XSTR (orig, i);
456 /* Subroutines of read_rtx. */
458 /* Dump code after printing a message. Used when read_rtx finds
462 dump_and_abort (expected_c, actual_c, infile)
463 int expected_c, actual_c;
470 "Expected character %c. Found character %c.",
471 expected_c, actual_c);
472 fprintf (stderr, " At file position: %ld\n", ftell (infile));
473 fprintf (stderr, "Following characters are:\n\t");
474 for (i = 0; i < 200; i++)
480 fprintf (stderr, "Aborting.\n");
484 /* Read chars from INFILE until a non-whitespace char
485 and return that. Comments, both Lisp style and C style,
486 are treated as whitespace.
487 Tools such as genflags use this function. */
490 read_skip_spaces (infile)
494 while (c = getc (infile))
496 if (c == ' ' || c == '\n' || c == '\t' || c == '\f')
500 while ((c = getc (infile)) && c != '\n') ;
507 dump_and_abort ('*', c, infile);
510 while (c = getc (infile))
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 /* Read an rtx in printed representation from INFILE
559 and return an actual rtx in core constructed accordingly.
560 read_rtx is not used in the compiler proper, but rather in
561 the utilities gen*.c that construct C code from machine descriptions. */
567 register int i, j, list_counter;
569 register char *format_ptr;
570 /* tmp_char is a buffer used for reading decimal integers
571 and names of rtx types and machine modes.
572 Therefore, 256 must be enough. */
577 HOST_WIDE_INT tmp_wide;
579 /* Linked list structure for making RTXs: */
582 struct rtx_list *next;
583 rtx value; /* Value of this node... */
586 c = read_skip_spaces (infile); /* Should be open paren. */
588 dump_and_abort ('(', c, infile);
590 read_name (tmp_char, infile);
594 for (i=0; i < NUM_RTX_CODE; i++) /* @@ might speed this search up */
596 if (!(strcmp (tmp_char, GET_RTX_NAME (i))))
598 tmp_code = (RTX_CODE) i; /* get value for name */
602 if (tmp_code == UNKNOWN)
605 "Unknown rtx read in rtl.read_rtx(). Code name was %s .",
608 /* (NIL) stands for an expression that isn't there. */
611 /* Discard the closeparen. */
612 while ((c = getc (infile)) && c != ')');
616 return_rtx = rtx_alloc (tmp_code); /* if we end up with an insn expression
617 then we free this space below. */
618 format_ptr = GET_RTX_FORMAT (GET_CODE (return_rtx));
620 /* If what follows is `: mode ', read it and
621 store the mode in the rtx. */
623 i = read_skip_spaces (infile);
627 read_name (tmp_char, infile);
628 for (k = 0; k < NUM_MACHINE_MODES; k++)
629 if (!strcmp (GET_MODE_NAME (k), tmp_char))
632 PUT_MODE (return_rtx, (enum machine_mode) k );
637 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (return_rtx)); i++)
638 switch (*format_ptr++)
640 /* 0 means a field for internal use only.
641 Don't expect it to be present in the input. */
647 XEXP (return_rtx, i) = read_rtx (infile);
651 /* 'V' is an optional vector: if a closeparen follows,
652 just store NULL for this element. */
653 c = read_skip_spaces (infile);
657 XVEC (return_rtx, i) = 0;
660 /* Now process the vector. */
664 register struct rtx_list *next_rtx, *rtx_list_link;
665 struct rtx_list *list_rtx;
667 c = read_skip_spaces (infile);
669 dump_and_abort ('[', c, infile);
671 /* add expressions to a list, while keeping a count */
674 while ((c = read_skip_spaces (infile)) && c != ']')
678 rtx_list_link = (struct rtx_list *)
679 alloca (sizeof (struct rtx_list));
680 rtx_list_link->value = read_rtx (infile);
682 list_rtx = rtx_list_link;
684 next_rtx->next = rtx_list_link;
685 next_rtx = rtx_list_link;
686 rtx_list_link->next = 0;
688 /* get vector length and allocate it */
689 XVEC (return_rtx, i) = (list_counter
690 ? rtvec_alloc (list_counter) : NULL_RTVEC);
691 if (list_counter > 0)
694 for (j = 0; j < list_counter; j++,
695 next_rtx = next_rtx->next)
696 XVECEXP (return_rtx, i, j) = next_rtx->value;
698 /* close bracket gotten */
703 /* 'S' is an optional string: if a closeparen follows,
704 just store NULL for this element. */
705 c = read_skip_spaces (infile);
709 XSTR (return_rtx, i) = 0;
716 register char *stringbuf;
718 c = read_skip_spaces (infile);
722 c = read_skip_spaces (infile);
725 dump_and_abort ('"', c, infile);
729 c = getc (infile); /* Read the string */
732 c = getc (infile); /* Read the string */
733 /* \; makes stuff for a C string constant containing
737 obstack_grow (rtl_obstack, "\\n\\t", 4);
744 obstack_1grow (rtl_obstack, c);
747 obstack_1grow (rtl_obstack, 0);
748 stringbuf = (char *) obstack_finish (rtl_obstack);
752 c = read_skip_spaces (infile);
754 dump_and_abort (')', c, infile);
756 XSTR (return_rtx, i) = stringbuf;
761 read_name (tmp_char, infile);
762 #if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_INT
763 tmp_wide = atoi (tmp_char);
765 tmp_wide = atol (tmp_char);
767 XWINT (return_rtx, i) = tmp_wide;
772 read_name (tmp_char, infile);
773 tmp_int = atoi (tmp_char);
774 XINT (return_rtx, i) = tmp_int;
779 "switch format wrong in rtl.read_rtx(). format was: %c.\n",
781 fprintf (stderr, "\tfile position: %ld\n", ftell (infile));
785 c = read_skip_spaces (infile);
787 dump_and_abort (')', c, infile);
792 /* This is called once per compilation, before any rtx's are constructed.
793 It initializes the vector `rtx_length', the extra CC modes, if any,
794 and computes certain commonly-used modes. */
799 int min_class_size[(int) MAX_MODE_CLASS];
800 enum machine_mode mode;
803 for (i = 0; i < NUM_RTX_CODE; i++)
804 rtx_length[i] = strlen (rtx_format[i]);
806 /* Make CONST_DOUBLE bigger, if real values are bigger than
807 it normally expects to have room for.
808 Note that REAL_VALUE_TYPE is not defined by default,
809 since tree.h is not included. But the default dfn as `double'
811 #ifdef REAL_VALUE_TYPE
812 i = sizeof (REAL_VALUE_TYPE) / sizeof (rtunion) + 2;
813 if (rtx_length[(int) CONST_DOUBLE] < i)
815 char *s = (char *) xmalloc (i + 1);
816 rtx_length[(int) CONST_DOUBLE] = i;
817 rtx_format[(int) CONST_DOUBLE] = s;
820 /* Set the GET_RTX_FORMAT of CONST_DOUBLE to a string
821 of as many `w's as we now have elements. Subtract two from
822 the size to account for the 'e' and the '0'. */
823 for (i = 2; i < rtx_length[(int) CONST_DOUBLE]; i++)
829 #ifdef EXTRA_CC_MODES
830 for (i = (int) CCmode + 1; i < (int) MAX_MACHINE_MODE; i++)
832 mode_class[i] = MODE_CC;
833 mode_size[i] = mode_size[(int) CCmode];
834 mode_unit_size[i] = mode_unit_size[(int) CCmode];
835 mode_wider_mode[i - 1] = (enum machine_mode) i;
836 mode_wider_mode[i] = VOIDmode;
840 /* Find the narrowest mode for each class. */
842 for (i = 0; i < (int) MAX_MODE_CLASS; i++)
843 min_class_size[i] = 1000;
845 for (mode = VOIDmode; (int) mode < (int) MAX_MACHINE_MODE;
846 mode = (enum machine_mode) ((int) mode + 1))
848 if (GET_MODE_SIZE (mode) < min_class_size[(int) GET_MODE_CLASS (mode)])
850 class_narrowest_mode[(int) GET_MODE_CLASS (mode)] = mode;
851 min_class_size[(int) GET_MODE_CLASS (mode)] = GET_MODE_SIZE (mode);