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 */
200 for (i=0; i < n; i++)
201 rt->elem[i].rtvec = NULL; /* @@ not portable due to rtunion */
206 /* Allocate an rtx of code CODE. The CODE is stored in the rtx;
207 all the rest is initialized to zero. */
214 register struct obstack *ob = rtl_obstack;
215 register int nelts = GET_RTX_LENGTH (code);
216 register int length = sizeof (struct rtx_def)
217 + (nelts - 1) * sizeof (rtunion);
219 /* This function is called more than any other in GCC,
220 so we manipulate the obstack directly.
222 Even though rtx objects are word aligned, we may be sharing an obstack
223 with tree nodes, which may have to be double-word aligned. So align
224 our length to the alignment mask in the obstack. */
226 length = (length + ob->alignment_mask) & ~ ob->alignment_mask;
228 if (ob->chunk_limit - ob->next_free < length)
229 _obstack_newchunk (ob, length);
230 rt = (rtx)ob->object_base;
231 ob->next_free += length;
232 ob->object_base = ob->next_free;
234 /* We want to clear everything up to the FLD array. Normally, this is
235 one int, but we don't want to assume that and it isn't very portable
238 length = (sizeof (struct rtx_def) - sizeof (rtunion) - 1) / sizeof (int);
239 for (; length >= 0; length--)
240 ((int *) rt)[length] = 0;
247 /* Free the rtx X and all RTL allocated since X. */
253 obstack_free (rtl_obstack, x);
256 /* Create a new copy of an rtx.
257 Recursively copies the operands of the rtx,
258 except for those few rtx codes that are sharable. */
266 register RTX_CODE code;
267 register char *format_ptr;
269 code = GET_CODE (orig);
282 /* SCRATCH must be shared because they represent distinct values. */
286 /* CONST can be shared if it contains a SYMBOL_REF. If it contains
287 a LABEL_REF, it isn't sharable. */
288 if (GET_CODE (XEXP (orig, 0)) == PLUS
289 && GET_CODE (XEXP (XEXP (orig, 0), 0)) == SYMBOL_REF
290 && GET_CODE (XEXP (XEXP (orig, 0), 1)) == CONST_INT)
294 /* A MEM with a constant address is not sharable. The problem is that
295 the constant address may need to be reloaded. If the mem is shared,
296 then reloading one copy of this mem will cause all copies to appear
297 to have been reloaded. */
300 copy = rtx_alloc (code);
301 PUT_MODE (copy, GET_MODE (orig));
302 copy->in_struct = orig->in_struct;
303 copy->volatil = orig->volatil;
304 copy->unchanging = orig->unchanging;
305 copy->integrated = orig->integrated;
307 format_ptr = GET_RTX_FORMAT (GET_CODE (copy));
309 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (copy)); i++)
311 switch (*format_ptr++)
314 XEXP (copy, i) = XEXP (orig, i);
315 if (XEXP (orig, i) != NULL)
316 XEXP (copy, i) = copy_rtx (XEXP (orig, i));
321 XEXP (copy, i) = XEXP (orig, i);
326 XVEC (copy, i) = XVEC (orig, i);
327 if (XVEC (orig, i) != NULL)
329 XVEC (copy, i) = rtvec_alloc (XVECLEN (orig, i));
330 for (j = 0; j < XVECLEN (copy, i); j++)
331 XVECEXP (copy, i, j) = copy_rtx (XVECEXP (orig, i, j));
336 XWINT (copy, i) = XWINT (orig, i);
340 XINT (copy, i) = XINT (orig, i);
345 XSTR (copy, i) = XSTR (orig, i);
355 /* Similar to `copy_rtx' except that if MAY_SHARE is present, it is
356 placed in the result directly, rather than being copied. */
359 copy_most_rtx (orig, may_share)
361 register rtx may_share;
365 register RTX_CODE code;
366 register char *format_ptr;
368 if (orig == may_share)
371 code = GET_CODE (orig);
386 copy = rtx_alloc (code);
387 PUT_MODE (copy, GET_MODE (orig));
388 copy->in_struct = orig->in_struct;
389 copy->volatil = orig->volatil;
390 copy->unchanging = orig->unchanging;
391 copy->integrated = orig->integrated;
393 format_ptr = GET_RTX_FORMAT (GET_CODE (copy));
395 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (copy)); i++)
397 switch (*format_ptr++)
400 XEXP (copy, i) = XEXP (orig, i);
401 if (XEXP (orig, i) != NULL && XEXP (orig, i) != may_share)
402 XEXP (copy, i) = copy_most_rtx (XEXP (orig, i), may_share);
407 XEXP (copy, i) = XEXP (orig, i);
412 XVEC (copy, i) = XVEC (orig, i);
413 if (XVEC (orig, i) != NULL)
415 XVEC (copy, i) = rtvec_alloc (XVECLEN (orig, i));
416 for (j = 0; j < XVECLEN (copy, i); j++)
418 = copy_most_rtx (XVECEXP (orig, i, j), may_share);
423 XWINT (copy, i) = XWINT (orig, i);
428 XINT (copy, i) = XINT (orig, i);
433 XSTR (copy, i) = XSTR (orig, i);
443 /* Subroutines of read_rtx. */
445 /* Dump code after printing a message. Used when read_rtx finds
449 dump_and_abort (expected_c, actual_c, infile)
450 int expected_c, actual_c;
457 "Expected character %c. Found character %c.",
458 expected_c, actual_c);
459 fprintf (stderr, " At file position: %ld\n", ftell (infile));
460 fprintf (stderr, "Following characters are:\n\t");
461 for (i = 0; i < 200; i++)
467 fprintf (stderr, "Aborting.\n");
471 /* Read chars from INFILE until a non-whitespace char
472 and return that. Comments, both Lisp style and C style,
473 are treated as whitespace.
474 Tools such as genflags use this function. */
477 read_skip_spaces (infile)
481 while (c = getc (infile))
483 if (c == ' ' || c == '\n' || c == '\t' || c == '\f')
487 while ((c = getc (infile)) && c != '\n') ;
494 dump_and_abort ('*', c, infile);
497 while (c = getc (infile))
499 if (prevc == '*' && c == '/')
509 /* Read an rtx code name into the buffer STR[].
510 It is terminated by any of the punctuation chars of rtx printed syntax. */
513 read_name (str, infile)
520 c = read_skip_spaces(infile);
525 if (c == ' ' || c == '\n' || c == '\t' || c == '\f')
527 if (c == ':' || c == ')' || c == ']' || c == '"' || c == '/'
528 || c == '(' || c == '[')
538 fprintf (stderr, "missing name or number");
539 dump_and_abort (-1, -1, infile);
545 /* Read an rtx in printed representation from INFILE
546 and return an actual rtx in core constructed accordingly.
547 read_rtx is not used in the compiler proper, but rather in
548 the utilities gen*.c that construct C code from machine descriptions. */
554 register int i, j, list_counter;
556 register char *format_ptr;
557 /* tmp_char is a buffer used for reading decimal integers
558 and names of rtx types and machine modes.
559 Therefore, 256 must be enough. */
564 HOST_WIDE_INT tmp_wide;
566 /* Linked list structure for making RTXs: */
569 struct rtx_list *next;
570 rtx value; /* Value of this node... */
573 c = read_skip_spaces (infile); /* Should be open paren. */
575 dump_and_abort ('(', c, infile);
577 read_name (tmp_char, infile);
581 for (i=0; i < NUM_RTX_CODE; i++) /* @@ might speed this search up */
583 if (!(strcmp (tmp_char, GET_RTX_NAME (i))))
585 tmp_code = (RTX_CODE) i; /* get value for name */
589 if (tmp_code == UNKNOWN)
592 "Unknown rtx read in rtl.read_rtx(). Code name was %s .",
595 /* (NIL) stands for an expression that isn't there. */
598 /* Discard the closeparen. */
599 while ((c = getc (infile)) && c != ')');
603 return_rtx = rtx_alloc (tmp_code); /* if we end up with an insn expression
604 then we free this space below. */
605 format_ptr = GET_RTX_FORMAT (GET_CODE (return_rtx));
607 /* If what follows is `: mode ', read it and
608 store the mode in the rtx. */
610 i = read_skip_spaces (infile);
614 read_name (tmp_char, infile);
615 for (k = 0; k < NUM_MACHINE_MODES; k++)
616 if (!strcmp (GET_MODE_NAME (k), tmp_char))
619 PUT_MODE (return_rtx, (enum machine_mode) k );
624 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (return_rtx)); i++)
625 switch (*format_ptr++)
627 /* 0 means a field for internal use only.
628 Don't expect it to be present in the input. */
634 XEXP (return_rtx, i) = read_rtx (infile);
638 /* 'V' is an optional vector: if a closeparen follows,
639 just store NULL for this element. */
640 c = read_skip_spaces (infile);
644 XVEC (return_rtx, i) = 0;
647 /* Now process the vector. */
651 register struct rtx_list *next_rtx, *rtx_list_link;
652 struct rtx_list *list_rtx;
654 c = read_skip_spaces (infile);
656 dump_and_abort ('[', c, infile);
658 /* add expressions to a list, while keeping a count */
661 while ((c = read_skip_spaces (infile)) && c != ']')
665 rtx_list_link = (struct rtx_list *)
666 alloca (sizeof (struct rtx_list));
667 rtx_list_link->value = read_rtx (infile);
669 list_rtx = rtx_list_link;
671 next_rtx->next = rtx_list_link;
672 next_rtx = rtx_list_link;
673 rtx_list_link->next = 0;
675 /* get vector length and allocate it */
676 XVEC (return_rtx, i) = (list_counter
677 ? rtvec_alloc (list_counter) : NULL_RTVEC);
678 if (list_counter > 0)
681 for (j = 0; j < list_counter; j++,
682 next_rtx = next_rtx->next)
683 XVECEXP (return_rtx, i, j) = next_rtx->value;
685 /* close bracket gotten */
690 /* 'S' is an optional string: if a closeparen follows,
691 just store NULL for this element. */
692 c = read_skip_spaces (infile);
696 XSTR (return_rtx, i) = 0;
703 register char *stringbuf;
705 c = read_skip_spaces (infile);
709 c = read_skip_spaces (infile);
712 dump_and_abort ('"', c, infile);
716 c = getc (infile); /* Read the string */
719 c = getc (infile); /* Read the string */
720 /* \; makes stuff for a C string constant containing
724 obstack_grow (rtl_obstack, "\\n\\t", 4);
731 obstack_1grow (rtl_obstack, c);
734 obstack_1grow (rtl_obstack, 0);
735 stringbuf = (char *) obstack_finish (rtl_obstack);
739 c = read_skip_spaces (infile);
741 dump_and_abort (')', c, infile);
743 XSTR (return_rtx, i) = stringbuf;
748 read_name (tmp_char, infile);
749 #if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_INT
750 tmp_wide = atoi (tmp_char);
752 tmp_wide = atol (tmp_char);
754 XWINT (return_rtx, i) = tmp_wide;
759 read_name (tmp_char, infile);
760 tmp_int = atoi (tmp_char);
761 XINT (return_rtx, i) = tmp_int;
766 "switch format wrong in rtl.read_rtx(). format was: %c.\n",
768 fprintf (stderr, "\tfile position: %ld\n", ftell (infile));
772 c = read_skip_spaces (infile);
774 dump_and_abort (')', c, infile);
779 /* This is called once per compilation, before any rtx's are constructed.
780 It initializes the vector `rtx_length', the extra CC modes, if any,
781 and computes certain commonly-used modes. */
786 int min_class_size[(int) MAX_MODE_CLASS];
787 enum machine_mode mode;
790 for (i = 0; i < NUM_RTX_CODE; i++)
791 rtx_length[i] = strlen (rtx_format[i]);
793 /* Make CONST_DOUBLE bigger, if real values are bigger than
794 it normally expects to have room for.
795 Note that REAL_VALUE_TYPE is not defined by default,
796 since tree.h is not included. But the default dfn as `double'
798 #ifdef REAL_VALUE_TYPE
799 i = sizeof (REAL_VALUE_TYPE) / sizeof (rtunion) + 2;
800 if (rtx_length[(int) CONST_DOUBLE] < i)
802 char *s = (char *) xmalloc (i + 1);
803 rtx_length[(int) CONST_DOUBLE] = i;
804 rtx_format[(int) CONST_DOUBLE] = s;
807 /* Set the GET_RTX_FORMAT of CONST_DOUBLE to a string
808 of as many `w's as we now have elements. Subtract two from
809 the size to account for the 'e' and the '0'. */
810 for (i = 2; i < rtx_length[(int) CONST_DOUBLE]; i++)
816 #ifdef EXTRA_CC_MODES
817 for (i = (int) CCmode + 1; i < (int) MAX_MACHINE_MODE; i++)
819 mode_class[i] = MODE_CC;
820 mode_size[i] = mode_size[(int) CCmode];
821 mode_unit_size[i] = mode_unit_size[(int) CCmode];
822 mode_wider_mode[i - 1] = (enum machine_mode) i;
823 mode_wider_mode[i] = VOIDmode;
827 /* Find the narrowest mode for each class. */
829 for (i = 0; i < (int) MAX_MODE_CLASS; i++)
830 min_class_size[i] = 1000;
832 for (mode = VOIDmode; (int) mode < (int) MAX_MACHINE_MODE;
833 mode = (enum machine_mode) ((int) mode + 1))
835 if (GET_MODE_SIZE (mode) < min_class_size[(int) GET_MODE_CLASS (mode)])
837 class_narrowest_mode[(int) GET_MODE_CLASS (mode)] = mode;
838 min_class_size[(int) GET_MODE_CLASS (mode)] = GET_MODE_SIZE (mode);
844 gcc_memset (dest, value, len)