1 /* Allocate and read RTL for GNU C Compiler.
2 Copyright (C) 1987, 1988, 1991 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, 675 Mass Ave, Cambridge, MA 02139, USA. */
27 #define obstack_chunk_alloc xmalloc
28 #define obstack_chunk_free free
29 extern int xmalloc ();
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;
42 /* Indexed by rtx code, gives number of operands for an rtx with that code.
43 Does NOT include rtx header data (code and links).
44 This array is initialized in init_rtl. */
46 int rtx_length[NUM_RTX_CODE + 1];
48 /* Indexed by rtx code, gives the name of that kind of rtx, as a C string. */
50 #define DEF_RTL_EXPR(ENUM, NAME, FORMAT, CLASS) NAME ,
53 #include "rtl.def" /* rtl expressions are documented here */
58 /* Indexed by machine mode, gives the name of that machine mode.
59 This name does not include the letters "mode". */
61 #define DEF_MACHMODE(SYM, NAME, CLASS, SIZE, UNIT, WIDER) NAME,
63 char *mode_name[(int) MAX_MACHINE_MODE] = {
64 #include "machmode.def"
74 /* Indexed by machine mode, gives the length of the mode, in bytes.
75 GET_MODE_CLASS uses this. */
77 #define DEF_MACHMODE(SYM, NAME, CLASS, SIZE, UNIT, WIDER) CLASS,
79 enum mode_class mode_class[(int) MAX_MACHINE_MODE] = {
80 #include "machmode.def"
85 /* Indexed by machine mode, gives the length of the mode, in bytes.
86 GET_MODE_SIZE uses this. */
88 #define DEF_MACHMODE(SYM, NAME, CLASS, SIZE, UNIT, WIDER) SIZE,
90 int mode_size[(int) MAX_MACHINE_MODE] = {
91 #include "machmode.def"
96 /* Indexed by machine mode, gives the length of the mode's subunit.
97 GET_MODE_UNIT_SIZE uses this. */
99 #define DEF_MACHMODE(SYM, NAME, CLASS, SIZE, UNIT, WIDER) UNIT,
101 int mode_unit_size[(int) MAX_MACHINE_MODE] = {
102 #include "machmode.def" /* machine modes are documented here */
107 /* Indexed by machine mode, gives next wider natural mode
108 (QI -> HI -> SI -> DI, etc.) Widening multiply instructions
111 #define DEF_MACHMODE(SYM, NAME, CLASS, SIZE, UNIT, WIDER) \
112 (enum machine_mode) WIDER,
114 enum machine_mode mode_wider_mode[(int) MAX_MACHINE_MODE] = {
115 #include "machmode.def" /* machine modes are documented here */
120 /* Indexed by mode class, gives the narrowest mode for each class. */
122 enum machine_mode class_narrowest_mode[(int) MAX_MODE_CLASS];
124 /* Commonly used modes. */
126 enum machine_mode byte_mode; /* Mode whose width is BITS_PER_UNIT */
127 enum machine_mode word_mode; /* Mode whose width is BITS_PER_WORD */
129 /* Indexed by rtx code, gives a sequence of operand-types for
130 rtx's of that code. The sequence is a C string in which
131 each character describes one operand. */
133 char *rtx_format[] = {
135 can cause a warning message
136 "0" field is unused (or used in a phase-dependent manner)
140 "n" like "i", but prints entries from `note_insn_name'
141 "s" a pointer to a string
143 "S" like "s", but optional:
144 the containing rtx may end before this operand
145 "e" a pointer to an rtl expression
146 prints the expression
147 "E" a pointer to a vector that points to a number of rtl expressions
148 prints a list of the rtl expressions
149 "V" like "E", but optional:
150 the containing rtx may end before this operand
151 "u" a pointer to another insn
152 prints the uid of the insn. */
154 #define DEF_RTL_EXPR(ENUM, NAME, FORMAT, CLASS) FORMAT ,
155 #include "rtl.def" /* rtl expressions are defined here */
159 /* Indexed by rtx code, gives a character representing the "class" of
160 that rtx code. See rtl.def for documentation on the defined classes. */
163 #define DEF_RTL_EXPR(ENUM, NAME, FORMAT, CLASS) CLASS,
164 #include "rtl.def" /* rtl expressions are defined here */
168 /* Names for kinds of NOTEs and REG_NOTEs. */
170 char *note_insn_name[] = { "NOTE_INSN_FUNCTION_BEG", "NOTE_INSN_DELETED",
171 "NOTE_INSN_BLOCK_BEG", "NOTE_INSN_BLOCK_END",
172 "NOTE_INSN_LOOP_BEG", "NOTE_INSN_LOOP_END",
173 "NOTE_INSN_FUNCTION_END", "NOTE_INSN_SETJMP",
174 "NOTE_INSN_LOOP_CONT", "NOTE_INSN_LOOP_VTOP" };
176 char *reg_note_name[] = { "", "REG_DEAD", "REG_INC", "REG_EQUIV", "REG_WAS_0",
177 "REG_EQUAL", "REG_RETVAL", "REG_LIBCALL",
178 "REG_NONNEG", "REG_NO_CONFLICT", "REG_UNUSED",
179 "REG_CC_SETTER", "REG_CC_USER", "REG_LABEL",
180 "REG_DEP_ANTI", "REG_DEP_OUTPUT" };
182 /* Allocate an rtx vector of N elements.
183 Store the length, and initialize all elements to zero. */
192 rt = (rtvec) obstack_alloc (rtl_obstack,
193 sizeof (struct rtvec_def)
194 + (( n - 1) * sizeof (rtunion)));
196 /* clear out the vector */
198 for (i=0; i < n; i++)
199 rt->elem[i].rtvec = NULL; /* @@ not portable due to rtunion */
204 /* Allocate an rtx of code CODE. The CODE is stored in the rtx;
205 all the rest is initialized to zero. */
212 register struct obstack *ob = rtl_obstack;
213 register int nelts = GET_RTX_LENGTH (code);
214 register int length = sizeof (struct rtx_def)
215 + (nelts - 1) * sizeof (rtunion);
217 /* This function is called more than any other in GCC,
218 so we manipulate the obstack directly.
220 Even though rtx objects are word aligned, we may be sharing an obstack
221 with tree nodes, which may have to be double-word aligned. So align
222 our length to the alignment mask in the obstack. */
224 length = (length + ob->alignment_mask) & ~ ob->alignment_mask;
226 if (ob->chunk_limit - ob->next_free < length)
227 _obstack_newchunk (ob, length);
228 rt = (rtx)ob->object_base;
229 ob->next_free += length;
230 ob->object_base = ob->next_free;
238 /* Create a new copy of an rtx.
239 Recursively copies the operands of the rtx,
240 except for those few rtx codes that are sharable. */
248 register RTX_CODE code;
249 register char *format_ptr;
251 code = GET_CODE (orig);
266 copy = rtx_alloc (code);
267 PUT_MODE (copy, GET_MODE (orig));
268 copy->in_struct = orig->in_struct;
269 copy->volatil = orig->volatil;
270 copy->unchanging = orig->unchanging;
271 copy->integrated = orig->integrated;
273 format_ptr = GET_RTX_FORMAT (GET_CODE (copy));
275 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (copy)); i++)
277 switch (*format_ptr++)
280 XEXP (copy, i) = XEXP (orig, i);
281 if (XEXP (orig, i) != NULL)
282 XEXP (copy, i) = copy_rtx (XEXP (orig, i));
286 XEXP (copy, i) = XEXP (orig, i);
291 XVEC (copy, i) = XVEC (orig, i);
292 if (XVEC (orig, i) != NULL)
294 XVEC (copy, i) = rtvec_alloc (XVECLEN (orig, i));
295 for (j = 0; j < XVECLEN (copy, i); j++)
296 XVECEXP (copy, i, j) = copy_rtx (XVECEXP (orig, i, j));
301 XINT (copy, i) = XINT (orig, i);
308 /* Similar to `copy_rtx' except that if MAY_SHARE is present, it is
309 placed in the result directly, rather than being copied. */
312 copy_most_rtx (orig, may_share)
314 register rtx may_share;
318 register RTX_CODE code;
319 register char *format_ptr;
321 if (orig == may_share)
324 code = GET_CODE (orig);
339 copy = rtx_alloc (code);
340 PUT_MODE (copy, GET_MODE (orig));
341 copy->in_struct = orig->in_struct;
342 copy->volatil = orig->volatil;
343 copy->unchanging = orig->unchanging;
344 copy->integrated = orig->integrated;
346 format_ptr = GET_RTX_FORMAT (GET_CODE (copy));
348 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (copy)); i++)
350 switch (*format_ptr++)
353 XEXP (copy, i) = XEXP (orig, i);
354 if (XEXP (orig, i) != NULL && XEXP (orig, i) != may_share)
355 XEXP (copy, i) = copy_most_rtx (XEXP (orig, i), may_share);
359 XEXP (copy, i) = XEXP (orig, i);
364 XVEC (copy, i) = XVEC (orig, i);
365 if (XVEC (orig, i) != NULL)
367 XVEC (copy, i) = rtvec_alloc (XVECLEN (orig, i));
368 for (j = 0; j < XVECLEN (copy, i); j++)
370 = copy_most_rtx (XVECEXP (orig, i, j), may_share);
375 XINT (copy, i) = XINT (orig, i);
382 /* Subroutines of read_rtx. */
384 /* Dump code after printing a message. Used when read_rtx finds
388 dump_and_abort (expected_c, actual_c, infile)
389 int expected_c, actual_c;
396 "Expected character %c. Found character %c.",
397 expected_c, actual_c);
398 fprintf (stderr, " At file position: %ld\n", ftell (infile));
399 fprintf (stderr, "Following characters are:\n\t");
400 for (i = 0; i < 200; i++)
406 fprintf (stderr, "Aborting.\n");
410 /* Read chars from INFILE until a non-whitespace char
411 and return that. Comments, both Lisp style and C style,
412 are treated as whitespace.
413 Tools such as genflags use this function. */
416 read_skip_spaces (infile)
420 while (c = getc (infile))
422 if (c == ' ' || c == '\n' || c == '\t' || c == '\f')
426 while ((c = getc (infile)) && c != '\n') ;
433 dump_and_abort ('*', c, infile);
436 while (c = getc (infile))
438 if (prevc == '*' && c == '/')
448 /* Read an rtx code name into the buffer STR[].
449 It is terminated by any of the punctuation chars of rtx printed syntax. */
452 read_name (str, infile)
459 c = read_skip_spaces(infile);
464 if (c == ' ' || c == '\n' || c == '\t' || c == '\f')
466 if (c == ':' || c == ')' || c == ']' || c == '"' || c == '/'
467 || c == '(' || c == '[')
477 fprintf (stderr, "missing name or number");
478 dump_and_abort (-1, -1, infile);
484 /* Read an rtx in printed representation from INFILE
485 and return an actual rtx in core constructed accordingly.
486 read_rtx is not used in the compiler proper, but rather in
487 the utilities gen*.c that construct C code from machine descriptions. */
493 register int i, j, list_counter;
495 register char *format_ptr;
496 /* tmp_char is a buffer used for reading decimal integers
497 and names of rtx types and machine modes.
498 Therefore, 256 must be enough. */
504 /* Linked list structure for making RTXs: */
507 struct rtx_list *next;
508 rtx value; /* Value of this node... */
511 c = read_skip_spaces (infile); /* Should be open paren. */
513 dump_and_abort ('(', c, infile);
515 read_name (tmp_char, infile);
519 for (i=0; i < NUM_RTX_CODE; i++) /* @@ might speed this search up */
521 if (!(strcmp (tmp_char, GET_RTX_NAME (i))))
523 tmp_code = (RTX_CODE) i; /* get value for name */
527 if (tmp_code == UNKNOWN)
530 "Unknown rtx read in rtl.read_rtx(). Code name was %s .",
533 /* (NIL) stands for an expression that isn't there. */
536 /* Discard the closeparen. */
537 while ((c = getc (infile)) && c != ')');
541 return_rtx = rtx_alloc (tmp_code); /* if we end up with an insn expression
542 then we free this space below. */
543 format_ptr = GET_RTX_FORMAT (GET_CODE (return_rtx));
545 /* If what follows is `: mode ', read it and
546 store the mode in the rtx. */
548 i = read_skip_spaces (infile);
552 read_name (tmp_char, infile);
553 for (k = 0; k < NUM_MACHINE_MODES; k++)
554 if (!strcmp (GET_MODE_NAME (k), tmp_char))
557 PUT_MODE (return_rtx, (enum machine_mode) k );
562 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (return_rtx)); i++)
563 switch (*format_ptr++)
565 /* 0 means a field for internal use only.
566 Don't expect it to be present in the input. */
572 XEXP (return_rtx, i) = read_rtx (infile);
576 /* 'V' is an optional vector: if a closeparen follows,
577 just store NULL for this element. */
578 c = read_skip_spaces (infile);
582 XVEC (return_rtx, i) = 0;
585 /* Now process the vector. */
589 register struct rtx_list *next_rtx, *rtx_list_link;
590 struct rtx_list *list_rtx;
592 c = read_skip_spaces (infile);
594 dump_and_abort ('[', c, infile);
596 /* add expressions to a list, while keeping a count */
599 while ((c = read_skip_spaces (infile)) && c != ']')
603 rtx_list_link = (struct rtx_list *)
604 alloca (sizeof (struct rtx_list));
605 rtx_list_link->value = read_rtx (infile);
607 list_rtx = rtx_list_link;
609 next_rtx->next = rtx_list_link;
610 next_rtx = rtx_list_link;
611 rtx_list_link->next = 0;
613 /* get vector length and allocate it */
614 XVEC (return_rtx, i) = (list_counter
615 ? rtvec_alloc (list_counter)
616 : (struct rtvec_def *) NULL);
617 if (list_counter > 0)
620 for (j = 0; j < list_counter; j++,
621 next_rtx = next_rtx->next)
622 XVECEXP (return_rtx, i, j) = next_rtx->value;
624 /* close bracket gotten */
629 /* 'S' is an optional string: if a closeparen follows,
630 just store NULL for this element. */
631 c = read_skip_spaces (infile);
635 XSTR (return_rtx, i) = 0;
642 register char *stringbuf;
645 c = read_skip_spaces (infile);
649 c = read_skip_spaces (infile);
652 dump_and_abort ('"', c, infile);
656 c = getc (infile); /* Read the string */
659 c = getc (infile); /* Read the string */
660 /* \; makes stuff for a C string constant containing
664 obstack_grow (rtl_obstack, "\\n\\t", 4);
671 obstack_1grow (rtl_obstack, c);
674 obstack_1grow (rtl_obstack, 0);
675 stringbuf = (char *) obstack_finish (rtl_obstack);
679 c = read_skip_spaces (infile);
681 dump_and_abort (')', c, infile);
683 XSTR (return_rtx, i) = stringbuf;
689 read_name (tmp_char, infile);
690 tmp_int = atoi (tmp_char);
691 XINT (return_rtx, i) = tmp_int;
696 "switch format wrong in rtl.read_rtx(). format was: %c.\n",
698 fprintf (stderr, "\tfile position: %ld\n", ftell (infile));
702 c = read_skip_spaces (infile);
704 dump_and_abort (')', c, infile);
709 /* This is called once per compilation, before any rtx's are constructed.
710 It initializes the vector `rtx_length', the extra CC modes, if any,
711 and computes certain commonly-used modes. */
716 int min_class_size[(int) MAX_MODE_CLASS];
717 enum machine_mode mode;
720 for (i = 0; i < NUM_RTX_CODE; i++)
721 rtx_length[i] = strlen (rtx_format[i]);
723 /* Make CONST_DOUBLE bigger, if real values are bigger than
724 it normally expects to have room for.
725 Note that REAL_VALUE_TYPE is not defined by default,
726 since tree.h is not included. But the default dfn as `double'
728 #ifdef REAL_VALUE_TYPE
729 i = sizeof (REAL_VALUE_TYPE) / sizeof (rtunion) + 2;
730 if (rtx_length[(int) CONST_DOUBLE] < i)
732 char *s = (char *) xmalloc (i + 1);
733 rtx_length[(int) CONST_DOUBLE] = i;
734 rtx_format[(int) CONST_DOUBLE] = s;
737 /* Set the GET_RTX_FORMAT of CONST_DOUBLE to a string
738 of as many `i's as we now have elements. */
739 for (i = 0; i < rtx_length[(int) CONST_DOUBLE]; i++)
745 #ifdef EXTRA_CC_MODES
746 for (i = (int) CCmode + 1; i < (int) MAX_MACHINE_MODE; i++)
748 mode_class[i] = MODE_CC;
749 mode_size[i] = mode_size[(int) CCmode];
750 mode_unit_size[i] = mode_unit_size[(int) CCmode];
751 mode_wider_mode[i - 1] = (enum machine_mode) i;
752 mode_wider_mode[i] = VOIDmode;
756 /* Find the narrowest mode for each class and compute the word and byte
759 for (i = 0; i < (int) MAX_MODE_CLASS; i++)
760 min_class_size[i] = 1000;
762 byte_mode = VOIDmode;
763 word_mode = VOIDmode;
765 for (mode = VOIDmode; (int) mode < (int) MAX_MACHINE_MODE;
766 mode = (enum machine_mode) ((int) mode + 1))
768 if (GET_MODE_SIZE (mode) < min_class_size[(int) GET_MODE_CLASS (mode)])
770 class_narrowest_mode[(int) GET_MODE_CLASS (mode)] = mode;
771 min_class_size[(int) GET_MODE_CLASS (mode)] = GET_MODE_SIZE (mode);
773 if (GET_MODE_CLASS (mode) == MODE_INT
774 && GET_MODE_BITSIZE (mode) == BITS_PER_UNIT
775 && byte_mode == VOIDmode)
778 if (GET_MODE_CLASS (mode) == MODE_INT
779 && GET_MODE_BITSIZE (mode) == BITS_PER_WORD
780 && word_mode == VOIDmode)
786 gcc_memset (dest, value, len)