configure.in (GLIBCPP_ENABLE_CXX_FLAGS): Do not pass arguments, let the defaults...
[official-gcc.git] / gcc / read-rtl.c
blob3869f70dab34c98f06bff451660db53985598ea9
1 /* RTL reader for GNU C Compiler.
2 Copyright (C) 1987, 1988, 1991, 1994, 1997, 1998, 1999, 2000, 2001, 2002
3 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 2, 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 COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
20 02111-1307, USA. */
22 #include "bconfig.h"
23 #include "system.h"
24 #include "coretypes.h"
25 #include "tm.h"
26 #include "rtl.h"
27 #include "obstack.h"
28 #include "hashtab.h"
30 static htab_t md_constants;
32 static void fatal_with_file_and_line PARAMS ((FILE *, const char *, ...))
33 ATTRIBUTE_PRINTF_2 ATTRIBUTE_NORETURN;
34 static void fatal_expected_char PARAMS ((FILE *, int, int)) ATTRIBUTE_NORETURN;
35 static void read_name PARAMS ((char *, FILE *));
36 static char *read_string PARAMS ((struct obstack *, FILE *, int));
37 static char *read_quoted_string PARAMS ((struct obstack *, FILE *));
38 static char *read_braced_string PARAMS ((struct obstack *, FILE *));
39 static void read_escape PARAMS ((struct obstack *, FILE *));
40 static hashval_t def_hash PARAMS ((const void *));
41 static int def_name_eq_p PARAMS ((const void *, const void *));
42 static void read_constants PARAMS ((FILE *infile, char *tmp_char));
43 static void validate_const_int PARAMS ((FILE *, const char *));
45 /* Subroutines of read_rtx. */
47 /* The current line number for the file. */
48 int read_rtx_lineno = 1;
50 /* The filename for aborting with file and line. */
51 const char *read_rtx_filename = "<unknown>";
53 static void
54 fatal_with_file_and_line VPARAMS ((FILE *infile, const char *msg, ...))
56 char context[64];
57 size_t i;
58 int c;
60 VA_OPEN (ap, msg);
61 VA_FIXEDARG (ap, FILE *, infile);
62 VA_FIXEDARG (ap, const char *, msg);
64 fprintf (stderr, "%s:%d: ", read_rtx_filename, read_rtx_lineno);
65 vfprintf (stderr, msg, ap);
66 putc ('\n', stderr);
68 /* Gather some following context. */
69 for (i = 0; i < sizeof (context)-1; ++i)
71 c = getc (infile);
72 if (c == EOF)
73 break;
74 if (c == '\r' || c == '\n')
75 break;
76 context[i] = c;
78 context[i] = '\0';
80 fprintf (stderr, "%s:%d: following context is `%s'\n",
81 read_rtx_filename, read_rtx_lineno, context);
83 VA_CLOSE (ap);
84 exit (1);
87 /* Dump code after printing a message. Used when read_rtx finds
88 invalid data. */
90 static void
91 fatal_expected_char (infile, expected_c, actual_c)
92 FILE *infile;
93 int expected_c, actual_c;
95 fatal_with_file_and_line (infile, "expected character `%c', found `%c'",
96 expected_c, actual_c);
99 /* Read chars from INFILE until a non-whitespace char
100 and return that. Comments, both Lisp style and C style,
101 are treated as whitespace.
102 Tools such as genflags use this function. */
105 read_skip_spaces (infile)
106 FILE *infile;
108 int c;
110 while (1)
112 c = getc (infile);
113 switch (c)
115 case '\n':
116 read_rtx_lineno++;
117 break;
119 case ' ': case '\t': case '\f': case '\r':
120 break;
122 case ';':
124 c = getc (infile);
125 while (c != '\n' && c != EOF);
126 read_rtx_lineno++;
127 break;
129 case '/':
131 int prevc;
132 c = getc (infile);
133 if (c != '*')
134 fatal_expected_char (infile, '*', c);
136 prevc = 0;
137 while ((c = getc (infile)) && c != EOF)
139 if (c == '\n')
140 read_rtx_lineno++;
141 else if (prevc == '*' && c == '/')
142 break;
143 prevc = c;
146 break;
148 default:
149 return c;
154 /* Read an rtx code name into the buffer STR[].
155 It is terminated by any of the punctuation chars of rtx printed syntax. */
157 static void
158 read_name (str, infile)
159 char *str;
160 FILE *infile;
162 char *p;
163 int c;
165 c = read_skip_spaces (infile);
167 p = str;
168 while (1)
170 if (c == ' ' || c == '\n' || c == '\t' || c == '\f' || c == '\r')
171 break;
172 if (c == ':' || c == ')' || c == ']' || c == '"' || c == '/'
173 || c == '(' || c == '[')
175 ungetc (c, infile);
176 break;
178 *p++ = c;
179 c = getc (infile);
181 if (p == str)
182 fatal_with_file_and_line (infile, "missing name or number");
183 if (c == '\n')
184 read_rtx_lineno++;
186 *p = 0;
188 if (md_constants)
190 /* Do constant expansion. */
191 struct md_constant *def;
193 p = str;
196 struct md_constant tmp_def;
198 tmp_def.name = p;
199 def = htab_find (md_constants, &tmp_def);
200 if (def)
201 p = def->value;
202 } while (def);
203 if (p != str)
204 strcpy (str, p);
208 /* Subroutine of the string readers. Handles backslash escapes.
209 Caller has read the backslash, but not placed it into the obstack. */
210 static void
211 read_escape (ob, infile)
212 struct obstack *ob;
213 FILE *infile;
215 int c = getc (infile);
217 switch (c)
219 /* Backslash-newline is replaced by nothing, as in C. */
220 case '\n':
221 read_rtx_lineno++;
222 return;
224 /* \" \' \\ are replaced by the second character. */
225 case '\\':
226 case '"':
227 case '\'':
228 break;
230 /* Standard C string escapes:
231 \a \b \f \n \r \t \v
232 \[0-7] \x
233 all are passed through to the output string unmolested.
234 In normal use these wind up in a string constant processed
235 by the C compiler, which will translate them appropriately.
236 We do not bother checking that \[0-7] are followed by up to
237 two octal digits, or that \x is followed by N hex digits.
238 \? \u \U are left out because they are not in traditional C. */
239 case 'a': case 'b': case 'f': case 'n': case 'r': case 't': case 'v':
240 case '0': case '1': case '2': case '3': case '4': case '5': case '6':
241 case '7': case 'x':
242 obstack_1grow (ob, '\\');
243 break;
245 /* \; makes stuff for a C string constant containing
246 newline and tab. */
247 case ';':
248 obstack_grow (ob, "\\n\\t", 4);
249 return;
251 /* pass anything else through, but issue a warning. */
252 default:
253 fprintf (stderr, "%s:%d: warning: unrecognized escape \\%c\n",
254 read_rtx_filename, read_rtx_lineno, c);
255 obstack_1grow (ob, '\\');
256 break;
259 obstack_1grow (ob, c);
263 /* Read a double-quoted string onto the obstack. Caller has scanned
264 the leading quote. */
265 static char *
266 read_quoted_string (ob, infile)
267 struct obstack *ob;
268 FILE *infile;
270 int c;
272 while (1)
274 c = getc (infile); /* Read the string */
275 if (c == '\n')
276 read_rtx_lineno++;
277 else if (c == '\\')
279 read_escape (ob, infile);
280 continue;
282 else if (c == '"')
283 break;
285 obstack_1grow (ob, c);
288 obstack_1grow (ob, 0);
289 return obstack_finish (ob);
292 /* Read a braced string (a la Tcl) onto the obstack. Caller has
293 scanned the leading brace. Note that unlike quoted strings,
294 the outermost braces _are_ included in the string constant. */
295 static char *
296 read_braced_string (ob, infile)
297 struct obstack *ob;
298 FILE *infile;
300 int c;
301 int brace_depth = 1; /* caller-processed */
303 obstack_1grow (ob, '{');
304 while (brace_depth)
306 c = getc (infile); /* Read the string */
307 if (c == '\n')
308 read_rtx_lineno++;
309 else if (c == '{')
310 brace_depth++;
311 else if (c == '}')
312 brace_depth--;
313 else if (c == '\\')
315 read_escape (ob, infile);
316 continue;
319 obstack_1grow (ob, c);
322 obstack_1grow (ob, 0);
323 return obstack_finish (ob);
326 /* Read some kind of string constant. This is the high-level routine
327 used by read_rtx. It handles surrounding parentheses, leading star,
328 and dispatch to the appropriate string constant reader. */
330 static char *
331 read_string (ob, infile, star_if_braced)
332 struct obstack *ob;
333 FILE *infile;
334 int star_if_braced;
336 char *stringbuf;
337 int saw_paren = 0;
338 int c;
340 c = read_skip_spaces (infile);
341 if (c == '(')
343 saw_paren = 1;
344 c = read_skip_spaces (infile);
347 if (c == '"')
348 stringbuf = read_quoted_string (ob, infile);
349 else if (c == '{')
351 if (star_if_braced)
352 obstack_1grow (ob, '*');
353 stringbuf = read_braced_string (ob, infile);
355 else
356 fatal_with_file_and_line (infile, "expected `\"' or `{', found `%c'", c);
358 if (saw_paren)
360 c = read_skip_spaces (infile);
361 if (c != ')')
362 fatal_expected_char (infile, ')', c);
365 return stringbuf;
368 /* Provide a version of a function to read a long long if the system does
369 not provide one. */
370 #if HOST_BITS_PER_WIDE_INT > HOST_BITS_PER_LONG && !defined(HAVE_ATOLL) && !defined(HAVE_ATOQ)
371 HOST_WIDE_INT
372 atoll (p)
373 const char *p;
375 int neg = 0;
376 HOST_WIDE_INT tmp_wide;
378 while (ISSPACE (*p))
379 p++;
380 if (*p == '-')
381 neg = 1, p++;
382 else if (*p == '+')
383 p++;
385 tmp_wide = 0;
386 while (ISDIGIT (*p))
388 HOST_WIDE_INT new_wide = tmp_wide*10 + (*p - '0');
389 if (new_wide < tmp_wide)
391 /* Return INT_MAX equiv on overflow. */
392 tmp_wide = (~(unsigned HOST_WIDE_INT) 0) >> 1;
393 break;
395 tmp_wide = new_wide;
396 p++;
399 if (neg)
400 tmp_wide = -tmp_wide;
401 return tmp_wide;
403 #endif
405 /* Given a constant definition, return a hash code for its name. */
406 static hashval_t
407 def_hash (def)
408 const void *def;
410 unsigned result, i;
411 const char *string = ((const struct md_constant *) def)->name;
413 for (result = i = 0;*string++ != '\0'; i++)
414 result += ((unsigned char) *string << (i % CHAR_BIT));
415 return result;
418 /* Given two constant definitions, return true if they have the same name. */
419 static int
420 def_name_eq_p (def1, def2)
421 const void *def1, *def2;
423 return ! strcmp (((const struct md_constant *) def1)->name,
424 ((const struct md_constant *) def2)->name);
427 /* INFILE is a FILE pointer to read text from. TMP_CHAR is a buffer suitable
428 to read a name or number into. Process a define_constants directive,
429 starting with the optional space after the "define_constants". */
430 static void
431 read_constants (infile, tmp_char)
432 FILE *infile;
433 char *tmp_char;
435 int c;
436 htab_t defs;
438 c = read_skip_spaces (infile);
439 if (c != '[')
440 fatal_expected_char (infile, '[', c);
441 defs = md_constants;
442 if (! defs)
443 defs = htab_create (32, def_hash, def_name_eq_p, (htab_del) 0);
444 /* Disable constant expansion during definition processing. */
445 md_constants = 0;
446 while ( (c = read_skip_spaces (infile)) != ']')
448 struct md_constant *def;
449 void **entry_ptr;
451 if (c != '(')
452 fatal_expected_char (infile, '(', c);
453 def = xmalloc (sizeof (struct md_constant));
454 def->name = tmp_char;
455 read_name (tmp_char, infile);
456 entry_ptr = htab_find_slot (defs, def, TRUE);
457 if (! *entry_ptr)
458 def->name = xstrdup (tmp_char);
459 c = read_skip_spaces (infile);
460 ungetc (c, infile);
461 read_name (tmp_char, infile);
462 if (! *entry_ptr)
464 def->value = xstrdup (tmp_char);
465 *entry_ptr = def;
467 else
469 def = *entry_ptr;
470 if (strcmp (def->value, tmp_char))
471 fatal_with_file_and_line (infile,
472 "redefinition of %s, was %s, now %s",
473 def->name, def->value, tmp_char);
475 c = read_skip_spaces (infile);
476 if (c != ')')
477 fatal_expected_char (infile, ')', c);
479 md_constants = defs;
480 c = read_skip_spaces (infile);
481 if (c != ')')
482 fatal_expected_char (infile, ')', c);
485 /* For every constant definition, call CALLBACK with two arguments:
486 a pointer a pointer to the constant definition and INFO.
487 Stops when CALLBACK returns zero. */
488 void
489 traverse_md_constants (callback, info)
490 htab_trav callback;
491 void *info;
493 if (md_constants)
494 htab_traverse (md_constants, callback, info);
497 static void
498 validate_const_int (infile, string)
499 FILE *infile;
500 const char *string;
502 const char *cp;
503 int valid = 1;
505 cp = string;
506 while (*cp && ISSPACE (*cp))
507 cp++;
508 if (*cp == '-' || *cp == '+')
509 cp++;
510 if (*cp == 0)
511 valid = 0;
512 for (; *cp; cp++)
513 if (! ISDIGIT (*cp))
514 valid = 0;
515 if (!valid)
516 fatal_with_file_and_line (infile, "invalid decimal constant \"%s\"\n", string);
519 /* Read an rtx in printed representation from INFILE
520 and return an actual rtx in core constructed accordingly.
521 read_rtx is not used in the compiler proper, but rather in
522 the utilities gen*.c that construct C code from machine descriptions. */
525 read_rtx (infile)
526 FILE *infile;
528 int i, j;
529 RTX_CODE tmp_code;
530 const char *format_ptr;
531 /* tmp_char is a buffer used for reading decimal integers
532 and names of rtx types and machine modes.
533 Therefore, 256 must be enough. */
534 char tmp_char[256];
535 rtx return_rtx;
536 int c;
537 int tmp_int;
538 HOST_WIDE_INT tmp_wide;
540 /* Obstack used for allocating RTL objects. */
541 static struct obstack rtl_obstack;
542 static int initialized;
544 /* Linked list structure for making RTXs: */
545 struct rtx_list
547 struct rtx_list *next;
548 rtx value; /* Value of this node. */
551 if (!initialized) {
552 obstack_init (&rtl_obstack);
553 initialized = 1;
556 again:
557 c = read_skip_spaces (infile); /* Should be open paren. */
558 if (c != '(')
559 fatal_expected_char (infile, '(', c);
561 read_name (tmp_char, infile);
563 tmp_code = UNKNOWN;
565 if (! strcmp (tmp_char, "define_constants"))
567 read_constants (infile, tmp_char);
568 goto again;
570 for (i = 0; i < NUM_RTX_CODE; i++)
571 if (! strcmp (tmp_char, GET_RTX_NAME (i)))
573 tmp_code = (RTX_CODE) i; /* get value for name */
574 break;
577 if (tmp_code == UNKNOWN)
578 fatal_with_file_and_line (infile, "unknown rtx code `%s'", tmp_char);
580 /* (NIL) stands for an expression that isn't there. */
581 if (tmp_code == NIL)
583 /* Discard the closeparen. */
584 while ((c = getc (infile)) && c != ')')
587 return 0;
590 /* If we end up with an insn expression then we free this space below. */
591 return_rtx = rtx_alloc (tmp_code);
592 format_ptr = GET_RTX_FORMAT (GET_CODE (return_rtx));
594 /* If what follows is `: mode ', read it and
595 store the mode in the rtx. */
597 i = read_skip_spaces (infile);
598 if (i == ':')
600 read_name (tmp_char, infile);
601 for (j = 0; j < NUM_MACHINE_MODES; j++)
602 if (! strcmp (GET_MODE_NAME (j), tmp_char))
603 break;
605 if (j == MAX_MACHINE_MODE)
606 fatal_with_file_and_line (infile, "unknown mode `%s'", tmp_char);
608 PUT_MODE (return_rtx, (enum machine_mode) j);
610 else
611 ungetc (i, infile);
613 for (i = 0; i < GET_RTX_LENGTH (GET_CODE (return_rtx)); i++)
614 switch (*format_ptr++)
616 /* 0 means a field for internal use only.
617 Don't expect it to be present in the input. */
618 case '0':
619 break;
621 case 'e':
622 case 'u':
623 XEXP (return_rtx, i) = read_rtx (infile);
624 break;
626 case 'V':
627 /* 'V' is an optional vector: if a closeparen follows,
628 just store NULL for this element. */
629 c = read_skip_spaces (infile);
630 ungetc (c, infile);
631 if (c == ')')
633 XVEC (return_rtx, i) = 0;
634 break;
636 /* Now process the vector. */
638 case 'E':
640 /* Obstack to store scratch vector in. */
641 struct obstack vector_stack;
642 int list_counter = 0;
643 rtvec return_vec = NULL_RTVEC;
645 c = read_skip_spaces (infile);
646 if (c != '[')
647 fatal_expected_char (infile, '[', c);
649 /* add expressions to a list, while keeping a count */
650 obstack_init (&vector_stack);
651 while ((c = read_skip_spaces (infile)) && c != ']')
653 ungetc (c, infile);
654 list_counter++;
655 obstack_ptr_grow (&vector_stack, (PTR) read_rtx (infile));
657 if (list_counter > 0)
659 return_vec = rtvec_alloc (list_counter);
660 memcpy (&return_vec->elem[0], obstack_finish (&vector_stack),
661 list_counter * sizeof (rtx));
663 XVEC (return_rtx, i) = return_vec;
664 obstack_free (&vector_stack, NULL);
665 /* close bracket gotten */
667 break;
669 case 'S':
670 /* 'S' is an optional string: if a closeparen follows,
671 just store NULL for this element. */
672 c = read_skip_spaces (infile);
673 ungetc (c, infile);
674 if (c == ')')
676 XSTR (return_rtx, i) = 0;
677 break;
680 case 'T':
681 case 's':
683 char *stringbuf;
685 /* The output template slot of a DEFINE_INSN,
686 DEFINE_INSN_AND_SPLIT, or DEFINE_PEEPHOLE automatically
687 gets a star inserted as its first character, if it is
688 written with a brace block instead of a string constant. */
689 int star_if_braced = (format_ptr[-1] == 'T');
691 stringbuf = read_string (&rtl_obstack, infile, star_if_braced);
693 /* For insn patterns, we want to provide a default name
694 based on the file and line, like "*foo.md:12", if the
695 given name is blank. These are only for define_insn and
696 define_insn_and_split, to aid debugging. */
697 if (*stringbuf == '\0'
698 && i == 0
699 && (GET_CODE (return_rtx) == DEFINE_INSN
700 || GET_CODE (return_rtx) == DEFINE_INSN_AND_SPLIT))
702 char line_name[20];
703 const char *fn = (read_rtx_filename ? read_rtx_filename : "rtx");
704 const char *slash;
705 for (slash = fn; *slash; slash ++)
706 if (*slash == '/' || *slash == '\\' || *slash == ':')
707 fn = slash + 1;
708 obstack_1grow (&rtl_obstack, '*');
709 obstack_grow (&rtl_obstack, fn, strlen (fn));
710 sprintf (line_name, ":%d", read_rtx_lineno);
711 obstack_grow (&rtl_obstack, line_name, strlen (line_name)+1);
712 stringbuf = (char *) obstack_finish (&rtl_obstack);
715 if (star_if_braced)
716 XTMPL (return_rtx, i) = stringbuf;
717 else
718 XSTR (return_rtx, i) = stringbuf;
720 break;
722 case 'w':
723 read_name (tmp_char, infile);
724 validate_const_int (infile, tmp_char);
725 #if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_INT
726 tmp_wide = atoi (tmp_char);
727 #else
728 #if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONG
729 tmp_wide = atol (tmp_char);
730 #else
731 /* Prefer atoll over atoq, since the former is in the ISO C99 standard.
732 But prefer not to use our hand-rolled function above either. */
733 #if defined(HAVE_ATOLL) || !defined(HAVE_ATOQ)
734 tmp_wide = atoll (tmp_char);
735 #else
736 tmp_wide = atoq (tmp_char);
737 #endif
738 #endif
739 #endif
740 XWINT (return_rtx, i) = tmp_wide;
741 break;
743 case 'i':
744 case 'n':
745 read_name (tmp_char, infile);
746 validate_const_int (infile, tmp_char);
747 tmp_int = atoi (tmp_char);
748 XINT (return_rtx, i) = tmp_int;
749 break;
751 default:
752 fprintf (stderr,
753 "switch format wrong in rtl.read_rtx(). format was: %c.\n",
754 format_ptr[-1]);
755 fprintf (stderr, "\tfile position: %ld\n", ftell (infile));
756 abort ();
759 c = read_skip_spaces (infile);
760 if (c != ')')
761 fatal_expected_char (infile, ')', c);
763 return return_rtx;