1 /* Allocate and read RTL for GNU C Compiler.
2 Copyright (C) 1987, 1988, 1991, 1994 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"};
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" };
184 /* Allocate an rtx vector of N elements.
185 Store the length, and initialize all elements to zero. */
194 rt = (rtvec) obstack_alloc (rtl_obstack,
195 sizeof (struct rtvec_def)
196 + (( n - 1) * sizeof (rtunion)));
198 /* clear out the vector */
199 PUT_NUM_ELEM (rt, n);
201 for (i = 0; i < n; i++)
202 rt->elem[i].rtwint = 0;
207 /* Allocate an rtx of code CODE. The CODE is stored in the rtx;
208 all the rest is initialized to zero. */
215 register struct obstack *ob = rtl_obstack;
216 register int nelts = GET_RTX_LENGTH (code);
217 register int length = sizeof (struct rtx_def)
218 + (nelts - 1) * sizeof (rtunion);
220 /* This function is called more than any other in GCC,
221 so we manipulate the obstack directly.
223 Even though rtx objects are word aligned, we may be sharing an obstack
224 with tree nodes, which may have to be double-word aligned. So align
225 our length to the alignment mask in the obstack. */
227 length = (length + ob->alignment_mask) & ~ ob->alignment_mask;
229 if (ob->chunk_limit - ob->next_free < length)
230 _obstack_newchunk (ob, length);
231 rt = (rtx)ob->object_base;
232 ob->next_free += length;
233 ob->object_base = ob->next_free;
235 /* We want to clear everything up to the FLD array. Normally, this is
236 one int, but we don't want to assume that and it isn't very portable
239 length = (sizeof (struct rtx_def) - sizeof (rtunion) - 1) / sizeof (int);
240 for (; length >= 0; length--)
241 ((int *) rt)[length] = 0;
248 /* Free the rtx X and all RTL allocated since X. */
254 obstack_free (rtl_obstack, x);
257 /* Create a new copy of an rtx.
258 Recursively copies the operands of the rtx,
259 except for those few rtx codes that are sharable. */
267 register RTX_CODE code;
268 register char *format_ptr;
270 code = GET_CODE (orig);
283 /* SCRATCH must be shared because they represent distinct values. */
287 /* CONST can be shared if it contains a SYMBOL_REF. If it contains
288 a LABEL_REF, it isn't sharable. */
289 if (GET_CODE (XEXP (orig, 0)) == PLUS
290 && GET_CODE (XEXP (XEXP (orig, 0), 0)) == SYMBOL_REF
291 && GET_CODE (XEXP (XEXP (orig, 0), 1)) == CONST_INT)
295 /* A MEM with a constant address is not sharable. The problem is that
296 the constant address may need to be reloaded. If the mem is shared,
297 then reloading one copy of this mem will cause all copies to appear
298 to have been reloaded. */
301 copy = rtx_alloc (code);
302 PUT_MODE (copy, GET_MODE (orig));
303 copy->in_struct = orig->in_struct;
304 copy->volatil = orig->volatil;
305 copy->unchanging = orig->unchanging;
306 copy->integrated = orig->integrated;
308 format_ptr = GET_RTX_FORMAT (GET_CODE (copy));
310 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (copy)); i++)
312 switch (*format_ptr++)
315 XEXP (copy, i) = XEXP (orig, i);
316 if (XEXP (orig, i) != NULL)
317 XEXP (copy, i) = copy_rtx (XEXP (orig, i));
322 XEXP (copy, i) = XEXP (orig, i);
327 XVEC (copy, i) = XVEC (orig, i);
328 if (XVEC (orig, i) != NULL)
330 XVEC (copy, i) = rtvec_alloc (XVECLEN (orig, i));
331 for (j = 0; j < XVECLEN (copy, i); j++)
332 XVECEXP (copy, i, j) = copy_rtx (XVECEXP (orig, i, j));
337 XWINT (copy, i) = XWINT (orig, i);
341 XINT (copy, i) = XINT (orig, i);
346 XSTR (copy, i) = XSTR (orig, i);
356 /* Similar to `copy_rtx' except that if MAY_SHARE is present, it is
357 placed in the result directly, rather than being copied. */
360 copy_most_rtx (orig, may_share)
362 register rtx may_share;
366 register RTX_CODE code;
367 register char *format_ptr;
369 if (orig == may_share)
372 code = GET_CODE (orig);
387 copy = rtx_alloc (code);
388 PUT_MODE (copy, GET_MODE (orig));
389 copy->in_struct = orig->in_struct;
390 copy->volatil = orig->volatil;
391 copy->unchanging = orig->unchanging;
392 copy->integrated = orig->integrated;
394 format_ptr = GET_RTX_FORMAT (GET_CODE (copy));
396 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (copy)); i++)
398 switch (*format_ptr++)
401 XEXP (copy, i) = XEXP (orig, i);
402 if (XEXP (orig, i) != NULL && XEXP (orig, i) != may_share)
403 XEXP (copy, i) = copy_most_rtx (XEXP (orig, i), may_share);
408 XEXP (copy, i) = XEXP (orig, i);
413 XVEC (copy, i) = XVEC (orig, i);
414 if (XVEC (orig, i) != NULL)
416 XVEC (copy, i) = rtvec_alloc (XVECLEN (orig, i));
417 for (j = 0; j < XVECLEN (copy, i); j++)
419 = copy_most_rtx (XVECEXP (orig, i, j), may_share);
424 XWINT (copy, i) = XWINT (orig, i);
429 XINT (copy, i) = XINT (orig, i);
434 XSTR (copy, i) = XSTR (orig, i);
444 /* Subroutines of read_rtx. */
446 /* Dump code after printing a message. Used when read_rtx finds
450 dump_and_abort (expected_c, actual_c, infile)
451 int expected_c, actual_c;
458 "Expected character %c. Found character %c.",
459 expected_c, actual_c);
460 fprintf (stderr, " At file position: %ld\n", ftell (infile));
461 fprintf (stderr, "Following characters are:\n\t");
462 for (i = 0; i < 200; i++)
468 fprintf (stderr, "Aborting.\n");
472 /* Read chars from INFILE until a non-whitespace char
473 and return that. Comments, both Lisp style and C style,
474 are treated as whitespace.
475 Tools such as genflags use this function. */
478 read_skip_spaces (infile)
482 while (c = getc (infile))
484 if (c == ' ' || c == '\n' || c == '\t' || c == '\f')
488 while ((c = getc (infile)) && c != '\n') ;
495 dump_and_abort ('*', c, infile);
498 while (c = getc (infile))
500 if (prevc == '*' && c == '/')
510 /* Read an rtx code name into the buffer STR[].
511 It is terminated by any of the punctuation chars of rtx printed syntax. */
514 read_name (str, infile)
521 c = read_skip_spaces(infile);
526 if (c == ' ' || c == '\n' || c == '\t' || c == '\f')
528 if (c == ':' || c == ')' || c == ']' || c == '"' || c == '/'
529 || c == '(' || c == '[')
539 fprintf (stderr, "missing name or number");
540 dump_and_abort (-1, -1, infile);
546 /* Read an rtx in printed representation from INFILE
547 and return an actual rtx in core constructed accordingly.
548 read_rtx is not used in the compiler proper, but rather in
549 the utilities gen*.c that construct C code from machine descriptions. */
555 register int i, j, list_counter;
557 register char *format_ptr;
558 /* tmp_char is a buffer used for reading decimal integers
559 and names of rtx types and machine modes.
560 Therefore, 256 must be enough. */
565 HOST_WIDE_INT tmp_wide;
567 /* Linked list structure for making RTXs: */
570 struct rtx_list *next;
571 rtx value; /* Value of this node... */
574 c = read_skip_spaces (infile); /* Should be open paren. */
576 dump_and_abort ('(', c, infile);
578 read_name (tmp_char, infile);
582 for (i=0; i < NUM_RTX_CODE; i++) /* @@ might speed this search up */
584 if (!(strcmp (tmp_char, GET_RTX_NAME (i))))
586 tmp_code = (RTX_CODE) i; /* get value for name */
590 if (tmp_code == UNKNOWN)
593 "Unknown rtx read in rtl.read_rtx(). Code name was %s .",
596 /* (NIL) stands for an expression that isn't there. */
599 /* Discard the closeparen. */
600 while ((c = getc (infile)) && c != ')');
604 return_rtx = rtx_alloc (tmp_code); /* if we end up with an insn expression
605 then we free this space below. */
606 format_ptr = GET_RTX_FORMAT (GET_CODE (return_rtx));
608 /* If what follows is `: mode ', read it and
609 store the mode in the rtx. */
611 i = read_skip_spaces (infile);
615 read_name (tmp_char, infile);
616 for (k = 0; k < NUM_MACHINE_MODES; k++)
617 if (!strcmp (GET_MODE_NAME (k), tmp_char))
620 PUT_MODE (return_rtx, (enum machine_mode) k );
625 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (return_rtx)); i++)
626 switch (*format_ptr++)
628 /* 0 means a field for internal use only.
629 Don't expect it to be present in the input. */
635 XEXP (return_rtx, i) = read_rtx (infile);
639 /* 'V' is an optional vector: if a closeparen follows,
640 just store NULL for this element. */
641 c = read_skip_spaces (infile);
645 XVEC (return_rtx, i) = 0;
648 /* Now process the vector. */
652 register struct rtx_list *next_rtx, *rtx_list_link;
653 struct rtx_list *list_rtx;
655 c = read_skip_spaces (infile);
657 dump_and_abort ('[', c, infile);
659 /* add expressions to a list, while keeping a count */
662 while ((c = read_skip_spaces (infile)) && c != ']')
666 rtx_list_link = (struct rtx_list *)
667 alloca (sizeof (struct rtx_list));
668 rtx_list_link->value = read_rtx (infile);
670 list_rtx = rtx_list_link;
672 next_rtx->next = rtx_list_link;
673 next_rtx = rtx_list_link;
674 rtx_list_link->next = 0;
676 /* get vector length and allocate it */
677 XVEC (return_rtx, i) = (list_counter
678 ? rtvec_alloc (list_counter) : NULL_RTVEC);
679 if (list_counter > 0)
682 for (j = 0; j < list_counter; j++,
683 next_rtx = next_rtx->next)
684 XVECEXP (return_rtx, i, j) = next_rtx->value;
686 /* close bracket gotten */
691 /* 'S' is an optional string: if a closeparen follows,
692 just store NULL for this element. */
693 c = read_skip_spaces (infile);
697 XSTR (return_rtx, i) = 0;
704 register char *stringbuf;
706 c = read_skip_spaces (infile);
710 c = read_skip_spaces (infile);
713 dump_and_abort ('"', c, infile);
717 c = getc (infile); /* Read the string */
720 c = getc (infile); /* Read the string */
721 /* \; makes stuff for a C string constant containing
725 obstack_grow (rtl_obstack, "\\n\\t", 4);
732 obstack_1grow (rtl_obstack, c);
735 obstack_1grow (rtl_obstack, 0);
736 stringbuf = (char *) obstack_finish (rtl_obstack);
740 c = read_skip_spaces (infile);
742 dump_and_abort (')', c, infile);
744 XSTR (return_rtx, i) = stringbuf;
749 read_name (tmp_char, infile);
750 #if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_INT
751 tmp_wide = atoi (tmp_char);
753 tmp_wide = atol (tmp_char);
755 XWINT (return_rtx, i) = tmp_wide;
760 read_name (tmp_char, infile);
761 tmp_int = atoi (tmp_char);
762 XINT (return_rtx, i) = tmp_int;
767 "switch format wrong in rtl.read_rtx(). format was: %c.\n",
769 fprintf (stderr, "\tfile position: %ld\n", ftell (infile));
773 c = read_skip_spaces (infile);
775 dump_and_abort (')', c, infile);
780 /* This is called once per compilation, before any rtx's are constructed.
781 It initializes the vector `rtx_length', the extra CC modes, if any,
782 and computes certain commonly-used modes. */
787 int min_class_size[(int) MAX_MODE_CLASS];
788 enum machine_mode mode;
791 for (i = 0; i < NUM_RTX_CODE; i++)
792 rtx_length[i] = strlen (rtx_format[i]);
794 /* Make CONST_DOUBLE bigger, if real values are bigger than
795 it normally expects to have room for.
796 Note that REAL_VALUE_TYPE is not defined by default,
797 since tree.h is not included. But the default dfn as `double'
799 #ifdef REAL_VALUE_TYPE
800 i = sizeof (REAL_VALUE_TYPE) / sizeof (rtunion) + 2;
801 if (rtx_length[(int) CONST_DOUBLE] < i)
803 char *s = (char *) xmalloc (i + 1);
804 rtx_length[(int) CONST_DOUBLE] = i;
805 rtx_format[(int) CONST_DOUBLE] = s;
808 /* Set the GET_RTX_FORMAT of CONST_DOUBLE to a string
809 of as many `w's as we now have elements. Subtract two from
810 the size to account for the 'e' and the '0'. */
811 for (i = 2; i < rtx_length[(int) CONST_DOUBLE]; i++)
817 #ifdef EXTRA_CC_MODES
818 for (i = (int) CCmode + 1; i < (int) MAX_MACHINE_MODE; i++)
820 mode_class[i] = MODE_CC;
821 mode_size[i] = mode_size[(int) CCmode];
822 mode_unit_size[i] = mode_unit_size[(int) CCmode];
823 mode_wider_mode[i - 1] = (enum machine_mode) i;
824 mode_wider_mode[i] = VOIDmode;
828 /* Find the narrowest mode for each class. */
830 for (i = 0; i < (int) MAX_MODE_CLASS; i++)
831 min_class_size[i] = 1000;
833 for (mode = VOIDmode; (int) mode < (int) MAX_MACHINE_MODE;
834 mode = (enum machine_mode) ((int) mode + 1))
836 if (GET_MODE_SIZE (mode) < min_class_size[(int) GET_MODE_CLASS (mode)])
838 class_narrowest_mode[(int) GET_MODE_CLASS (mode)] = mode;
839 min_class_size[(int) GET_MODE_CLASS (mode)] = GET_MODE_SIZE (mode);
845 gcc_memset (dest, value, len)