gcc/genextract.c

   1 /* Generate code from machine description to extract operands from insn as rtl.
   2    Copyright (C) 1987, 91, 92, 93, 97, 1998 Free Software Foundation, Inc.
   3
   4 This file is part of GNU CC.
   5
   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)
   9 any later version.
  10
  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.
  15
  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.  */
  20
  21
  22 #include "hconfig.h"
  23 #include "system.h"
  24 #include "rtl.h"
  25 #include "obstack.h"
  26 #include "insn-config.h"
  27
  28 static struct obstack obstack;
  29 struct obstack *rtl_obstack = &obstack;
  30
  31 #define obstack_chunk_alloc xmalloc
  32 #define obstack_chunk_free free
  33
  34 /* Names for patterns.  Need to allow linking with print-rtl.  */
  35 char **insn_name_ptr;
  36
  37 /* This structure contains all the information needed to describe one
  38    set of extractions methods.  Each method may be used by more than
  39    one pattern if the operands are in the same place.
  40
  41    The string for each operand describes that path to the operand and
  42    contains `0' through `9' when going into an expression and `a' through
  43    `z' when going into a vector.  We assume here that only the first operand
  44    of an rtl expression is a vector.  genrecog.c makes the same assumption
  45    (and uses the same representation) and it is currently true.  */
  46
  47 struct extraction
  48 {
  49   int op_count;
  50   char *oplocs[MAX_RECOG_OPERANDS];
  51   int dup_count;
  52   char *duplocs[MAX_DUP_OPERANDS];
  53   int dupnums[MAX_DUP_OPERANDS];
  54   struct code_ptr *insns;
  55   struct extraction *next;
  56 };
  57
  58 /* Holds a single insn code that use an extraction method.  */
  59
  60 struct code_ptr
  61 {
  62   int insn_code;
  63   struct code_ptr *next;
  64 };
  65
  66 static struct extraction *extractions;
  67
  68 /* Number instruction patterns handled, starting at 0 for first one.  */
  69
  70 static int insn_code_number;
  71
  72 /* Records the large operand number in this insn.  */
  73
  74 static int op_count;
  75
  76 /* Records the location of any operands using the string format described
  77    above.  */
  78
  79 static char *oplocs[MAX_RECOG_OPERANDS];
  80
  81 /* Number the occurrences of MATCH_DUP in each instruction,
  82    starting at 0 for the first occurrence.  */
  83
  84 static int dup_count;
  85
  86 /* Records the location of any MATCH_DUP operands.  */
  87
  88 static char *duplocs[MAX_DUP_OPERANDS];
  89
  90 /* Record the operand number of any MATCH_DUPs.  */
  91
  92 static int dupnums[MAX_DUP_OPERANDS];
  93
  94 /* Record the list of insn_codes for peepholes.  */
  95
  96 static struct code_ptr *peepholes;
  97
  98 static void gen_insn PROTO ((rtx));
  99 static void walk_rtx PROTO ((rtx, char *));
 100 static void print_path PROTO ((char *));
 101 char *xmalloc PROTO ((unsigned));
 102 char *xrealloc PROTO ((char *, unsigned));
 103 static void fatal PVPROTO ((char *, ...))
 104   ATTRIBUTE_PRINTF_1 ATTRIBUTE_NORETURN;
 105 static char *copystr PROTO ((char *));
 106 static void mybzero ();
 107 void fancy_abort PROTO ((void)) ATTRIBUTE_NORETURN;
 108 \f
 109 static void
 110 gen_insn (insn)
 111      rtx insn;
 112 {
 113   register int i;
 114   register struct extraction *p;
 115   register struct code_ptr *link;
 116
 117   op_count = 0;
 118   dup_count = 0;
 119
 120   /* No operands seen so far in this pattern.  */
 121   mybzero (oplocs, sizeof oplocs);
 122
 123   /* Walk the insn's pattern, remembering at all times the path
 124      down to the walking point.  */
 125
 126   if (XVECLEN (insn, 1) == 1)
 127     walk_rtx (XVECEXP (insn, 1, 0), "");
 128   else
 129     for (i = XVECLEN (insn, 1) - 1; i >= 0; i--)
 130       {
 131         char *path = (char *) alloca (2);
 132
 133         path[0] = 'a' + i;
 134         path[1] = 0;
 135
 136         walk_rtx (XVECEXP (insn, 1, i), path);
 137       }
 138
 139   link = (struct code_ptr *) xmalloc (sizeof (struct code_ptr));
 140   link->insn_code = insn_code_number;
 141
 142   /* See if we find something that already had this extraction method.  */
 143
 144   for (p = extractions; p; p = p->next)
 145     {
 146       if (p->op_count != op_count || p->dup_count != dup_count)
 147         continue;
 148
 149       for (i = 0; i < op_count; i++)
 150         if (p->oplocs[i] != oplocs[i]
 151             && ! (p->oplocs[i] != 0 && oplocs[i] != 0
 152                   && ! strcmp (p->oplocs[i], oplocs[i])))
 153           break;
 154
 155       if (i != op_count)
 156         continue;
 157
 158       for (i = 0; i < dup_count; i++)
 159         if (p->dupnums[i] != dupnums[i]
 160             || strcmp (p->duplocs[i], duplocs[i]))
 161           break;
 162
 163       if (i != dup_count)
 164         continue;
 165
 166       /* This extraction is the same as ours.  Just link us in.  */
 167       link->next = p->insns;
 168       p->insns = link;
 169       return;
 170     }
 171
 172   /* Otherwise, make a new extraction method.  */
 173
 174   p = (struct extraction *) xmalloc (sizeof (struct extraction));
 175   p->op_count = op_count;
 176   p->dup_count = dup_count;
 177   p->next = extractions;
 178   extractions = p;
 179   p->insns = link;
 180   link->next = 0;
 181
 182   for (i = 0; i < op_count; i++)
 183     p->oplocs[i] = oplocs[i];
 184
 185   for (i = 0; i < dup_count; i++)
 186     p->dupnums[i] = dupnums[i], p->duplocs[i] = duplocs[i];
 187 }
 188 \f
 189 static void
 190 walk_rtx (x, path)
 191      rtx x;
 192      char *path;
 193 {
 194   register RTX_CODE code;
 195   register int i;
 196   register int len;
 197   register char *fmt;
 198   int depth = strlen (path);
 199   char *newpath;
 200
 201   if (x == 0)
 202     return;
 203
 204   code = GET_CODE (x);
 205
 206   switch (code)
 207     {
 208     case PC:
 209     case CC0:
 210     case CONST_INT:
 211     case SYMBOL_REF:
 212       return;
 213
 214     case MATCH_OPERAND:
 215     case MATCH_SCRATCH:
 216       oplocs[XINT (x, 0)] = copystr (path);
 217       op_count = MAX (op_count, XINT (x, 0) + 1);
 218       break;
 219
 220     case MATCH_DUP:
 221     case MATCH_PAR_DUP:
 222       duplocs[dup_count] = copystr (path);
 223       dupnums[dup_count] = XINT (x, 0);
 224       dup_count++;
 225       break;
 226
 227     case MATCH_OP_DUP:
 228       duplocs[dup_count] = copystr (path);
 229       dupnums[dup_count] = XINT (x, 0);
 230       dup_count++;
 231
 232       newpath = (char *) alloca (depth + 2);
 233       strcpy (newpath, path);
 234       newpath[depth + 1] = 0;
 235
 236       for (i = XVECLEN (x, 1) - 1; i >= 0; i--)
 237         {
 238           newpath[depth] = '0' + i;
 239           walk_rtx (XVECEXP (x, 1, i), newpath);
 240         }
 241       return;
 242
 243     case MATCH_OPERATOR:
 244       oplocs[XINT (x, 0)] = copystr (path);
 245       op_count = MAX (op_count, XINT (x, 0) + 1);
 246
 247       newpath = (char *) alloca (depth + 2);
 248       strcpy (newpath, path);
 249       newpath[depth + 1] = 0;
 250
 251       for (i = XVECLEN (x, 2) - 1; i >= 0; i--)
 252         {
 253           newpath[depth] = '0' + i;
 254           walk_rtx (XVECEXP (x, 2, i), newpath);
 255         }
 256       return;
 257
 258     case MATCH_PARALLEL:
 259       oplocs[XINT (x, 0)] = copystr (path);
 260       op_count = MAX (op_count, XINT (x, 0) + 1);
 261
 262       newpath = (char *) alloca (depth + 2);
 263       strcpy (newpath, path);
 264       newpath[depth + 1] = 0;
 265
 266       for (i = XVECLEN (x, 2) - 1; i >= 0; i--)
 267         {
 268           newpath[depth] = 'a' + i;
 269           walk_rtx (XVECEXP (x, 2, i), newpath);
 270         }
 271       return;
 272
 273     case ADDRESS:
 274       walk_rtx (XEXP (x, 0), path);
 275       return;
 276
 277     default:
 278       break;
 279     }
 280
 281   newpath = (char *) alloca (depth + 2);
 282   strcpy (newpath, path);
 283   newpath[depth + 1] = 0;
 284
 285   fmt = GET_RTX_FORMAT (code);
 286   len = GET_RTX_LENGTH (code);
 287   for (i = 0; i < len; i++)
 288     {
 289       if (fmt[i] == 'e' || fmt[i] == 'u')
 290         {
 291           newpath[depth] = '0' + i;
 292           walk_rtx (XEXP (x, i), newpath);
 293         }
 294       else if (fmt[i] == 'E')
 295         {
 296           int j;
 297           for (j = XVECLEN (x, i) - 1; j >= 0; j--)
 298             {
 299               newpath[depth] = 'a' + j;
 300               walk_rtx (XVECEXP (x, i, j), newpath);
 301             }
 302         }
 303     }
 304 }
 305
 306 /* Given a PATH, representing a path down the instruction's
 307    pattern from the root to a certain point, output code to
 308    evaluate to the rtx at that point.  */
 309
 310 static void
 311 print_path (path)
 312      char *path;
 313 {
 314   register int len = strlen (path);
 315   register int i;
 316
 317   if (len == 0)
 318     {
 319       /* Don't emit "pat", since we may try to take the address of it,
 320          which isn't what is intended.  */
 321       printf("PATTERN (insn)");
 322       return;
 323     }
 324
 325   /* We first write out the operations (XEXP or XVECEXP) in reverse
 326      order, then write "insn", then the indices in forward order.  */
 327
 328   for (i = len - 1; i >=0 ; i--)
 329     {
 330       if (path[i] >= 'a' && path[i] <= 'z')
 331         printf ("XVECEXP (");
 332       else if (path[i] >= '0' && path[i] <= '9')
 333         printf ("XEXP (");
 334       else
 335         abort ();
 336     }
 337
 338   printf ("pat");
 339
 340   for (i = 0; i < len; i++)
 341     {
 342       if (path[i] >= 'a' && path[i] <= 'z')
 343         printf (", 0, %d)", path[i] - 'a');
 344       else if (path[i] >= '0' && path[i] <= '9')
 345         printf (", %d)", path[i] - '0');
 346       else
 347         abort ();
 348     }
 349 }
 350 \f
 351 char *
 352 xmalloc (size)
 353      unsigned size;
 354 {
 355   register char *val = (char *) malloc (size);
 356
 357   if (val == 0)
 358     fatal ("virtual memory exhausted");
 359   return val;
 360 }
 361
 362 char *
 363 xrealloc (ptr, size)
 364      char *ptr;
 365      unsigned size;
 366 {
 367   char *result = (char *) realloc (ptr, size);
 368   if (!result)
 369     fatal ("virtual memory exhausted");
 370   return result;
 371 }
 372
 373 static void
 374 fatal VPROTO ((char *format, ...))
 375 {
 376 #ifndef __STDC__
 377   char *format;
 378 #endif
 379   va_list ap;
 380
 381   VA_START (ap, format);
 382
 383 #ifndef __STDC__
 384   format = va_arg (ap, char *);
 385 #endif
 386
 387   fprintf (stderr, "genextract: ");
 388   vfprintf (stderr, format, ap);
 389   va_end (ap);
 390   fprintf (stderr, "\n");
 391   exit (FATAL_EXIT_CODE);
 392 }
 393
 394 /* More 'friendly' abort that prints the line and file.
 395    config.h can #define abort fancy_abort if you like that sort of thing.  */
 396
 397 void
 398 fancy_abort ()
 399 {
 400   fatal ("Internal gcc abort.");
 401 }
 402
 403 static char *
 404 copystr (s1)
 405      char *s1;
 406 {
 407   register char *tem;
 408
 409   if (s1 == 0)
 410     return 0;
 411
 412   tem = (char *) xmalloc (strlen (s1) + 1);
 413   strcpy (tem, s1);
 414
 415   return tem;
 416 }
 417
 418 static void
 419 mybzero (b, length)
 420      register char *b;
 421      register unsigned length;
 422 {
 423   while (length-- > 0)
 424     *b++ = 0;
 425 }
 426 \f
 427 int
 428 main (argc, argv)
 429      int argc;
 430      char **argv;
 431 {
 432   rtx desc;
 433   FILE *infile;
 434   register int c, i;
 435   struct extraction *p;
 436   struct code_ptr *link;
 437
 438   obstack_init (rtl_obstack);
 439
 440   if (argc <= 1)
 441     fatal ("No input file name.");
 442
 443   infile = fopen (argv[1], "r");
 444   if (infile == 0)
 445     {
 446       perror (argv[1]);
 447       exit (FATAL_EXIT_CODE);
 448     }
 449
 450   init_rtl ();
 451
 452   /* Assign sequential codes to all entries in the machine description
 453      in parallel with the tables in insn-output.c.  */
 454
 455   insn_code_number = 0;
 456
 457   printf ("/* Generated automatically by the program `genextract'\n\
 458 from the machine description file `md'.  */\n\n");
 459
 460   printf ("#include \"config.h\"\n");
 461   printf ("#include \"system.h\"\n");
 462   printf ("#include \"rtl.h\"\n");
 463   printf ("#include \"insn-config.h\"\n");
 464   printf ("#include \"recog.h\"\n");
 465   printf ("#include \"toplev.h\"\n\n");
 466
 467   /* This variable exists only so it can be the "location"
 468      of any missing operand whose numbers are skipped by a given pattern.  */
 469   printf ("static rtx junk ATTRIBUTE_UNUSED;\n");
 470
 471   printf ("void\ninsn_extract (insn)\n");
 472   printf ("     rtx insn;\n");
 473   printf ("{\n");
 474   printf ("  register rtx *ro = recog_operand;\n");
 475   printf ("  register rtx **ro_loc = recog_operand_loc;\n");
 476   printf ("  rtx pat = PATTERN (insn);\n");
 477   printf ("  int i ATTRIBUTE_UNUSED;\n\n");
 478   printf ("  switch (INSN_CODE (insn))\n");
 479   printf ("    {\n");
 480   printf ("    case -1:\n");
 481   printf ("      fatal_insn_not_found (insn);\n\n");
 482
 483   /* Read the machine description.  */
 484
 485   while (1)
 486     {
 487       c = read_skip_spaces (infile);
 488       if (c == EOF)
 489         break;
 490       ungetc (c, infile);
 491
 492       desc = read_rtx (infile);
 493       if (GET_CODE (desc) == DEFINE_INSN)
 494         {
 495           gen_insn (desc);
 496           ++insn_code_number;
 497         }
 498
 499       else if (GET_CODE (desc) == DEFINE_PEEPHOLE)
 500         {
 501           struct code_ptr *link
 502             = (struct code_ptr *) xmalloc (sizeof (struct code_ptr));
 503
 504           link->insn_code = insn_code_number;
 505           link->next = peepholes;
 506           peepholes = link;
 507           ++insn_code_number;
 508         }
 509
 510       else if (GET_CODE (desc) == DEFINE_EXPAND
 511                || GET_CODE (desc) == DEFINE_SPLIT)
 512         ++insn_code_number;
 513     }
 514
 515   /* Write out code to handle peepholes and the insn_codes that it should
 516      be called for.  */
 517   if (peepholes)
 518     {
 519       for (link = peepholes; link; link = link->next)
 520         printf ("    case %d:\n", link->insn_code);
 521
 522       /* The vector in the insn says how many operands it has.
 523          And all it contains are operands.  In fact, the vector was
 524          created just for the sake of this function.  */
 525       printf ("      for (i = XVECLEN (pat, 0) - 1; i >= 0; i--)\n");
 526       printf ("          ro[i] = XVECEXP (pat, 0, i);\n");
 527       printf ("      break;\n\n");
 528     }
 529
 530   /* Write out all the ways to extract insn operands.  */
 531   for (p = extractions; p; p = p->next)
 532     {
 533       for (link = p->insns; link; link = link->next)
 534         printf ("    case %d:\n", link->insn_code);
 535
 536       for (i = 0; i < p->op_count; i++)
 537         {
 538           if (p->oplocs[i] == 0)
 539             {
 540               printf ("      ro[%d] = const0_rtx;\n", i);
 541               printf ("      ro_loc[%d] = &junk;\n", i);
 542             }
 543           else
 544             {
 545               printf ("      ro[%d] = *(ro_loc[%d] = &", i, i);
 546               print_path (p->oplocs[i]);
 547               printf (");\n");
 548             }
 549         }
 550
 551       for (i = 0; i < p->dup_count; i++)
 552         {
 553           printf ("      recog_dup_loc[%d] = &", i);
 554           print_path (p->duplocs[i]);
 555           printf (";\n");
 556           printf ("      recog_dup_num[%d] = %d;\n", i, p->dupnums[i]);
 557         }
 558
 559       printf ("      break;\n\n");
 560     }
 561
 562   /* This should never be reached.  Note that we would also reach this abort
 563    if we tried to extract something whose INSN_CODE was a DEFINE_EXPAND or
 564    DEFINE_SPLIT, but that is correct.  */
 565   printf ("    default:\n      abort ();\n");
 566
 567   printf ("    }\n}\n");
 568
 569   fflush (stdout);
 570   exit (ferror (stdout) != 0 ? FATAL_EXIT_CODE : SUCCESS_EXIT_CODE);
 571   /* NOTREACHED */
 572   return 0;
 573 }