2009-10-24 Paul Thomas <pault@gcc.gnu.org>
[official-gcc.git] / gcc / rtl.c
blobaefbbf347d935bd3f56d26ae74064e59803a7fe0
1 /* RTL utility routines.
2 Copyright (C) 1987, 1988, 1991, 1994, 1997, 1998, 1999, 2000, 2001, 2002,
3 2003, 2004, 2005, 2006, 2007, 2008, 2009 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 3, or (at your option) any later
10 version.
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
21 /* This file is compiled twice: once for the generator programs
22 once for the compiler. */
23 #ifdef GENERATOR_FILE
24 #include "bconfig.h"
25 #else
26 #include "config.h"
27 #endif
29 #include "system.h"
30 #include "coretypes.h"
31 #include "tm.h"
32 #include "rtl.h"
33 #include "real.h"
34 #include "ggc.h"
35 #ifdef GENERATOR_FILE
36 # include "errors.h"
37 #else
38 # include "toplev.h"
39 #endif
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). */
45 #define DEF_RTL_EXPR(ENUM, NAME, FORMAT, CLASS) sizeof FORMAT - 1 ,
47 const unsigned char rtx_length[NUM_RTX_CODE] = {
48 #include "rtl.def"
51 #undef DEF_RTL_EXPR
53 /* Indexed by rtx code, gives the name of that kind of rtx, as a C string. */
55 #define DEF_RTL_EXPR(ENUM, NAME, FORMAT, CLASS) NAME ,
57 const char * const rtx_name[NUM_RTX_CODE] = {
58 #include "rtl.def" /* rtl expressions are documented here */
61 #undef DEF_RTL_EXPR
63 /* Indexed by rtx code, gives a sequence of operand-types for
64 rtx's of that code. The sequence is a C string in which
65 each character describes one operand. */
67 const char * const rtx_format[NUM_RTX_CODE] = {
68 /* "*" undefined.
69 can cause a warning message
70 "0" field is unused (or used in a phase-dependent manner)
71 prints nothing
72 "i" an integer
73 prints the integer
74 "n" like "i", but prints entries from `note_insn_name'
75 "w" an integer of width HOST_BITS_PER_WIDE_INT
76 prints the integer
77 "s" a pointer to a string
78 prints the string
79 "S" like "s", but optional:
80 the containing rtx may end before this operand
81 "T" like "s", but treated specially by the RTL reader;
82 only found in machine description patterns.
83 "e" a pointer to an rtl expression
84 prints the expression
85 "E" a pointer to a vector that points to a number of rtl expressions
86 prints a list of the rtl expressions
87 "V" like "E", but optional:
88 the containing rtx may end before this operand
89 "u" a pointer to another insn
90 prints the uid of the insn.
91 "b" is a pointer to a bitmap header.
92 "B" is a basic block pointer.
93 "t" is a tree pointer. */
95 #define DEF_RTL_EXPR(ENUM, NAME, FORMAT, CLASS) FORMAT ,
96 #include "rtl.def" /* rtl expressions are defined here */
97 #undef DEF_RTL_EXPR
100 /* Indexed by rtx code, gives a character representing the "class" of
101 that rtx code. See rtl.def for documentation on the defined classes. */
103 const enum rtx_class rtx_class[NUM_RTX_CODE] = {
104 #define DEF_RTL_EXPR(ENUM, NAME, FORMAT, CLASS) CLASS,
105 #include "rtl.def" /* rtl expressions are defined here */
106 #undef DEF_RTL_EXPR
109 /* Indexed by rtx code, gives the size of the rtx in bytes. */
111 const unsigned char rtx_code_size[NUM_RTX_CODE] = {
112 #define DEF_RTL_EXPR(ENUM, NAME, FORMAT, CLASS) \
113 ((ENUM) == CONST_INT || (ENUM) == CONST_DOUBLE || (ENUM) == CONST_FIXED\
114 ? RTX_HDR_SIZE + (sizeof FORMAT - 1) * sizeof (HOST_WIDE_INT) \
115 : RTX_HDR_SIZE + (sizeof FORMAT - 1) * sizeof (rtunion)),
117 #include "rtl.def"
118 #undef DEF_RTL_EXPR
121 /* Names for kinds of NOTEs and REG_NOTEs. */
123 const char * const note_insn_name[NOTE_INSN_MAX] =
125 #define DEF_INSN_NOTE(NAME) #NAME,
126 #include "insn-notes.def"
127 #undef DEF_INSN_NOTE
130 const char * const reg_note_name[REG_NOTE_MAX] =
132 #define DEF_REG_NOTE(NAME) #NAME,
133 #include "reg-notes.def"
134 #undef DEF_REG_NOTE
137 #ifdef GATHER_STATISTICS
138 static int rtx_alloc_counts[(int) LAST_AND_UNUSED_RTX_CODE];
139 static int rtx_alloc_sizes[(int) LAST_AND_UNUSED_RTX_CODE];
140 static int rtvec_alloc_counts;
141 static int rtvec_alloc_sizes;
142 #endif
145 /* Allocate an rtx vector of N elements.
146 Store the length, and initialize all elements to zero. */
148 rtvec
149 rtvec_alloc (int n)
151 rtvec rt;
153 rt = ggc_alloc_rtvec (n);
154 /* Clear out the vector. */
155 memset (&rt->elem[0], 0, n * sizeof (rtx));
157 PUT_NUM_ELEM (rt, n);
159 #ifdef GATHER_STATISTICS
160 rtvec_alloc_counts++;
161 rtvec_alloc_sizes += n * sizeof (rtx);
162 #endif
164 return rt;
167 /* Create a bitwise copy of VEC. */
169 rtvec
170 shallow_copy_rtvec (rtvec vec)
172 rtvec newvec;
173 int n;
175 n = GET_NUM_ELEM (vec);
176 newvec = rtvec_alloc (n);
177 memcpy (&newvec->elem[0], &vec->elem[0], sizeof (rtx) * n);
178 return newvec;
181 /* Return the number of bytes occupied by rtx value X. */
183 unsigned int
184 rtx_size (const_rtx x)
186 if (GET_CODE (x) == SYMBOL_REF && SYMBOL_REF_HAS_BLOCK_INFO_P (x))
187 return RTX_HDR_SIZE + sizeof (struct block_symbol);
188 return RTX_CODE_SIZE (GET_CODE (x));
191 /* Allocate an rtx of code CODE. The CODE is stored in the rtx;
192 all the rest is initialized to zero. */
195 rtx_alloc_stat (RTX_CODE code MEM_STAT_DECL)
197 rtx rt;
199 rt = (rtx) ggc_alloc_zone_pass_stat (RTX_CODE_SIZE (code), &rtl_zone);
201 /* We want to clear everything up to the FLD array. Normally, this
202 is one int, but we don't want to assume that and it isn't very
203 portable anyway; this is. */
205 memset (rt, 0, RTX_HDR_SIZE);
206 PUT_CODE (rt, code);
208 #ifdef GATHER_STATISTICS
209 rtx_alloc_counts[code]++;
210 rtx_alloc_sizes[code] += RTX_CODE_SIZE (code);
211 #endif
213 return rt;
217 /* Return true if ORIG is a sharable CONST. */
219 bool
220 shared_const_p (const_rtx orig)
222 gcc_assert (GET_CODE (orig) == CONST);
224 /* CONST can be shared if it contains a SYMBOL_REF. If it contains
225 a LABEL_REF, it isn't sharable. */
226 return (GET_CODE (XEXP (orig, 0)) == PLUS
227 && GET_CODE (XEXP (XEXP (orig, 0), 0)) == SYMBOL_REF
228 && CONST_INT_P(XEXP (XEXP (orig, 0), 1)));
232 /* Create a new copy of an rtx.
233 Recursively copies the operands of the rtx,
234 except for those few rtx codes that are sharable. */
237 copy_rtx (rtx orig)
239 rtx copy;
240 int i, j;
241 RTX_CODE code;
242 const char *format_ptr;
244 code = GET_CODE (orig);
246 switch (code)
248 case REG:
249 case DEBUG_EXPR:
250 case VALUE:
251 case CONST_INT:
252 case CONST_DOUBLE:
253 case CONST_FIXED:
254 case CONST_VECTOR:
255 case SYMBOL_REF:
256 case CODE_LABEL:
257 case PC:
258 case CC0:
259 case SCRATCH:
260 /* SCRATCH must be shared because they represent distinct values. */
261 return orig;
262 case CLOBBER:
263 if (REG_P (XEXP (orig, 0)) && REGNO (XEXP (orig, 0)) < FIRST_PSEUDO_REGISTER)
264 return orig;
265 break;
267 case CONST:
268 if (shared_const_p (orig))
269 return orig;
270 break;
272 /* A MEM with a constant address is not sharable. The problem is that
273 the constant address may need to be reloaded. If the mem is shared,
274 then reloading one copy of this mem will cause all copies to appear
275 to have been reloaded. */
277 default:
278 break;
281 /* Copy the various flags, fields, and other information. We assume
282 that all fields need copying, and then clear the fields that should
283 not be copied. That is the sensible default behavior, and forces
284 us to explicitly document why we are *not* copying a flag. */
285 copy = shallow_copy_rtx (orig);
287 /* We do not copy the USED flag, which is used as a mark bit during
288 walks over the RTL. */
289 RTX_FLAG (copy, used) = 0;
291 /* We do not copy FRAME_RELATED for INSNs. */
292 if (INSN_P (orig))
293 RTX_FLAG (copy, frame_related) = 0;
294 RTX_FLAG (copy, jump) = RTX_FLAG (orig, jump);
295 RTX_FLAG (copy, call) = RTX_FLAG (orig, call);
297 format_ptr = GET_RTX_FORMAT (GET_CODE (copy));
299 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (copy)); i++)
300 switch (*format_ptr++)
302 case 'e':
303 if (XEXP (orig, i) != NULL)
304 XEXP (copy, i) = copy_rtx (XEXP (orig, i));
305 break;
307 case 'E':
308 case 'V':
309 if (XVEC (orig, i) != NULL)
311 XVEC (copy, i) = rtvec_alloc (XVECLEN (orig, i));
312 for (j = 0; j < XVECLEN (copy, i); j++)
313 XVECEXP (copy, i, j) = copy_rtx (XVECEXP (orig, i, j));
315 break;
317 case 't':
318 case 'w':
319 case 'i':
320 case 's':
321 case 'S':
322 case 'T':
323 case 'u':
324 case 'B':
325 case '0':
326 /* These are left unchanged. */
327 break;
329 default:
330 gcc_unreachable ();
332 return copy;
335 /* Create a new copy of an rtx. Only copy just one level. */
338 shallow_copy_rtx_stat (const_rtx orig MEM_STAT_DECL)
340 const unsigned int size = rtx_size (orig);
341 rtx const copy = (rtx) ggc_alloc_zone_pass_stat (size, &rtl_zone);
342 return (rtx) memcpy (copy, orig, size);
345 /* Nonzero when we are generating CONCATs. */
346 int generating_concat_p;
348 /* Nonzero when we are expanding trees to RTL. */
349 int currently_expanding_to_rtl;
353 /* Same as rtx_equal_p, but call CB on each pair of rtx if CB is not NULL.
354 When the callback returns true, we continue with the new pair.
355 Whenever changing this function check if rtx_equal_p below doesn't need
356 changing as well. */
359 rtx_equal_p_cb (const_rtx x, const_rtx y, rtx_equal_p_callback_function cb)
361 int i;
362 int j;
363 enum rtx_code code;
364 const char *fmt;
365 rtx nx, ny;
367 if (x == y)
368 return 1;
369 if (x == 0 || y == 0)
370 return 0;
372 /* Invoke the callback first. */
373 if (cb != NULL
374 && ((*cb) (&x, &y, &nx, &ny)))
375 return rtx_equal_p_cb (nx, ny, cb);
377 code = GET_CODE (x);
378 /* Rtx's of different codes cannot be equal. */
379 if (code != GET_CODE (y))
380 return 0;
382 /* (MULT:SI x y) and (MULT:HI x y) are NOT equivalent.
383 (REG:SI x) and (REG:HI x) are NOT equivalent. */
385 if (GET_MODE (x) != GET_MODE (y))
386 return 0;
388 /* Some RTL can be compared nonrecursively. */
389 switch (code)
391 case REG:
392 return (REGNO (x) == REGNO (y));
394 case LABEL_REF:
395 return XEXP (x, 0) == XEXP (y, 0);
397 case SYMBOL_REF:
398 return XSTR (x, 0) == XSTR (y, 0);
400 case DEBUG_EXPR:
401 case VALUE:
402 case SCRATCH:
403 case CONST_DOUBLE:
404 case CONST_INT:
405 case CONST_FIXED:
406 return 0;
408 default:
409 break;
412 /* Compare the elements. If any pair of corresponding elements
413 fail to match, return 0 for the whole thing. */
415 fmt = GET_RTX_FORMAT (code);
416 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
418 switch (fmt[i])
420 case 'w':
421 if (XWINT (x, i) != XWINT (y, i))
422 return 0;
423 break;
425 case 'n':
426 case 'i':
427 if (XINT (x, i) != XINT (y, i))
428 return 0;
429 break;
431 case 'V':
432 case 'E':
433 /* Two vectors must have the same length. */
434 if (XVECLEN (x, i) != XVECLEN (y, i))
435 return 0;
437 /* And the corresponding elements must match. */
438 for (j = 0; j < XVECLEN (x, i); j++)
439 if (rtx_equal_p_cb (XVECEXP (x, i, j),
440 XVECEXP (y, i, j), cb) == 0)
441 return 0;
442 break;
444 case 'e':
445 if (rtx_equal_p_cb (XEXP (x, i), XEXP (y, i), cb) == 0)
446 return 0;
447 break;
449 case 'S':
450 case 's':
451 if ((XSTR (x, i) || XSTR (y, i))
452 && (! XSTR (x, i) || ! XSTR (y, i)
453 || strcmp (XSTR (x, i), XSTR (y, i))))
454 return 0;
455 break;
457 case 'u':
458 /* These are just backpointers, so they don't matter. */
459 break;
461 case '0':
462 case 't':
463 break;
465 /* It is believed that rtx's at this level will never
466 contain anything but integers and other rtx's,
467 except for within LABEL_REFs and SYMBOL_REFs. */
468 default:
469 gcc_unreachable ();
472 return 1;
475 /* Return 1 if X and Y are identical-looking rtx's.
476 This is the Lisp function EQUAL for rtx arguments.
477 Whenever changing this function check if rtx_equal_p_cb above doesn't need
478 changing as well. */
481 rtx_equal_p (const_rtx x, const_rtx y)
483 int i;
484 int j;
485 enum rtx_code code;
486 const char *fmt;
488 if (x == y)
489 return 1;
490 if (x == 0 || y == 0)
491 return 0;
493 code = GET_CODE (x);
494 /* Rtx's of different codes cannot be equal. */
495 if (code != GET_CODE (y))
496 return 0;
498 /* (MULT:SI x y) and (MULT:HI x y) are NOT equivalent.
499 (REG:SI x) and (REG:HI x) are NOT equivalent. */
501 if (GET_MODE (x) != GET_MODE (y))
502 return 0;
504 /* Some RTL can be compared nonrecursively. */
505 switch (code)
507 case REG:
508 return (REGNO (x) == REGNO (y));
510 case LABEL_REF:
511 return XEXP (x, 0) == XEXP (y, 0);
513 case SYMBOL_REF:
514 return XSTR (x, 0) == XSTR (y, 0);
516 case DEBUG_EXPR:
517 case VALUE:
518 case SCRATCH:
519 case CONST_DOUBLE:
520 case CONST_INT:
521 case CONST_FIXED:
522 return 0;
524 default:
525 break;
528 /* Compare the elements. If any pair of corresponding elements
529 fail to match, return 0 for the whole thing. */
531 fmt = GET_RTX_FORMAT (code);
532 for (i = GET_RTX_LENGTH (code) - 1; i >= 0; i--)
534 switch (fmt[i])
536 case 'w':
537 if (XWINT (x, i) != XWINT (y, i))
538 return 0;
539 break;
541 case 'n':
542 case 'i':
543 if (XINT (x, i) != XINT (y, i))
544 return 0;
545 break;
547 case 'V':
548 case 'E':
549 /* Two vectors must have the same length. */
550 if (XVECLEN (x, i) != XVECLEN (y, i))
551 return 0;
553 /* And the corresponding elements must match. */
554 for (j = 0; j < XVECLEN (x, i); j++)
555 if (rtx_equal_p (XVECEXP (x, i, j), XVECEXP (y, i, j)) == 0)
556 return 0;
557 break;
559 case 'e':
560 if (rtx_equal_p (XEXP (x, i), XEXP (y, i)) == 0)
561 return 0;
562 break;
564 case 'S':
565 case 's':
566 if ((XSTR (x, i) || XSTR (y, i))
567 && (! XSTR (x, i) || ! XSTR (y, i)
568 || strcmp (XSTR (x, i), XSTR (y, i))))
569 return 0;
570 break;
572 case 'u':
573 /* These are just backpointers, so they don't matter. */
574 break;
576 case '0':
577 case 't':
578 break;
580 /* It is believed that rtx's at this level will never
581 contain anything but integers and other rtx's,
582 except for within LABEL_REFs and SYMBOL_REFs. */
583 default:
584 gcc_unreachable ();
587 return 1;
590 void
591 dump_rtx_statistics (void)
593 #ifdef GATHER_STATISTICS
594 int i;
595 int total_counts = 0;
596 int total_sizes = 0;
597 fprintf (stderr, "\nRTX Kind Count Bytes\n");
598 fprintf (stderr, "---------------------------------------\n");
599 for (i = 0; i < LAST_AND_UNUSED_RTX_CODE; i++)
600 if (rtx_alloc_counts[i])
602 fprintf (stderr, "%-20s %7d %10d\n", GET_RTX_NAME (i),
603 rtx_alloc_counts[i], rtx_alloc_sizes[i]);
604 total_counts += rtx_alloc_counts[i];
605 total_sizes += rtx_alloc_sizes[i];
607 if (rtvec_alloc_counts)
609 fprintf (stderr, "%-20s %7d %10d\n", "rtvec",
610 rtvec_alloc_counts, rtvec_alloc_sizes);
611 total_counts += rtvec_alloc_counts;
612 total_sizes += rtvec_alloc_sizes;
614 fprintf (stderr, "---------------------------------------\n");
615 fprintf (stderr, "%-20s %7d %10d\n",
616 "Total", total_counts, total_sizes);
617 fprintf (stderr, "---------------------------------------\n");
618 #endif
621 #if defined ENABLE_RTL_CHECKING && (GCC_VERSION >= 2007)
622 void
623 rtl_check_failed_bounds (const_rtx r, int n, const char *file, int line,
624 const char *func)
626 internal_error
627 ("RTL check: access of elt %d of '%s' with last elt %d in %s, at %s:%d",
628 n, GET_RTX_NAME (GET_CODE (r)), GET_RTX_LENGTH (GET_CODE (r)) - 1,
629 func, trim_filename (file), line);
632 void
633 rtl_check_failed_type1 (const_rtx r, int n, int c1, const char *file, int line,
634 const char *func)
636 internal_error
637 ("RTL check: expected elt %d type '%c', have '%c' (rtx %s) in %s, at %s:%d",
638 n, c1, GET_RTX_FORMAT (GET_CODE (r))[n], GET_RTX_NAME (GET_CODE (r)),
639 func, trim_filename (file), line);
642 void
643 rtl_check_failed_type2 (const_rtx r, int n, int c1, int c2, const char *file,
644 int line, const char *func)
646 internal_error
647 ("RTL check: expected elt %d type '%c' or '%c', have '%c' (rtx %s) in %s, at %s:%d",
648 n, c1, c2, GET_RTX_FORMAT (GET_CODE (r))[n], GET_RTX_NAME (GET_CODE (r)),
649 func, trim_filename (file), line);
652 void
653 rtl_check_failed_code1 (const_rtx r, enum rtx_code code, const char *file,
654 int line, const char *func)
656 internal_error ("RTL check: expected code '%s', have '%s' in %s, at %s:%d",
657 GET_RTX_NAME (code), GET_RTX_NAME (GET_CODE (r)), func,
658 trim_filename (file), line);
661 void
662 rtl_check_failed_code2 (const_rtx r, enum rtx_code code1, enum rtx_code code2,
663 const char *file, int line, const char *func)
665 internal_error
666 ("RTL check: expected code '%s' or '%s', have '%s' in %s, at %s:%d",
667 GET_RTX_NAME (code1), GET_RTX_NAME (code2), GET_RTX_NAME (GET_CODE (r)),
668 func, trim_filename (file), line);
671 void
672 rtl_check_failed_code_mode (const_rtx r, enum rtx_code code, enum machine_mode mode,
673 bool not_mode, const char *file, int line,
674 const char *func)
676 internal_error ((not_mode
677 ? ("RTL check: expected code '%s' and not mode '%s', "
678 "have code '%s' and mode '%s' in %s, at %s:%d")
679 : ("RTL check: expected code '%s' and mode '%s', "
680 "have code '%s' and mode '%s' in %s, at %s:%d")),
681 GET_RTX_NAME (code), GET_MODE_NAME (mode),
682 GET_RTX_NAME (GET_CODE (r)), GET_MODE_NAME (GET_MODE (r)),
683 func, trim_filename (file), line);
686 /* Report that line LINE of FILE tried to access the block symbol fields
687 of a non-block symbol. FUNC is the function that contains the line. */
689 void
690 rtl_check_failed_block_symbol (const char *file, int line, const char *func)
692 internal_error
693 ("RTL check: attempt to treat non-block symbol as a block symbol "
694 "in %s, at %s:%d", func, trim_filename (file), line);
697 /* XXX Maybe print the vector? */
698 void
699 rtvec_check_failed_bounds (const_rtvec r, int n, const char *file, int line,
700 const char *func)
702 internal_error
703 ("RTL check: access of elt %d of vector with last elt %d in %s, at %s:%d",
704 n, GET_NUM_ELEM (r) - 1, func, trim_filename (file), line);
706 #endif /* ENABLE_RTL_CHECKING */
708 #if defined ENABLE_RTL_FLAG_CHECKING
709 void
710 rtl_check_failed_flag (const char *name, const_rtx r, const char *file,
711 int line, const char *func)
713 internal_error
714 ("RTL flag check: %s used with unexpected rtx code '%s' in %s, at %s:%d",
715 name, GET_RTX_NAME (GET_CODE (r)), func, trim_filename (file), line);
717 #endif /* ENABLE_RTL_FLAG_CHECKING */