gcc/genextract.c

   1 /* Generate code from machine description to extract operands from insn as rtl.
   2    Copyright (C) 1987, 91-93, 97-98, 1999 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, const char *));
 100 static void print_path PROTO ((char *));
 101 static void fatal PVPROTO ((const char *, ...))
 102   ATTRIBUTE_PRINTF_1 ATTRIBUTE_NORETURN;
 103 void fancy_abort PROTO ((void)) ATTRIBUTE_NORETURN;
 104 \f
 105 static void
 106 gen_insn (insn)
 107      rtx insn;
 108 {
 109   register int i;
 110   register struct extraction *p;
 111   register struct code_ptr *link;
 112
 113   op_count = 0;
 114   dup_count = 0;
 115
 116   /* No operands seen so far in this pattern.  */
 117   memset (oplocs, 0, sizeof oplocs);
 118
 119   /* Walk the insn's pattern, remembering at all times the path
 120      down to the walking point.  */
 121
 122   if (XVECLEN (insn, 1) == 1)
 123     walk_rtx (XVECEXP (insn, 1, 0), "");
 124   else
 125     for (i = XVECLEN (insn, 1) - 1; i >= 0; i--)
 126       {
 127         char *path = (char *) alloca (2);
 128
 129         path[0] = 'a' + i;
 130         path[1] = 0;
 131
 132         walk_rtx (XVECEXP (insn, 1, i), path);
 133       }
 134
 135   link = (struct code_ptr *) xmalloc (sizeof (struct code_ptr));
 136   link->insn_code = insn_code_number;
 137
 138   /* See if we find something that already had this extraction method.  */
 139
 140   for (p = extractions; p; p = p->next)
 141     {
 142       if (p->op_count != op_count || p->dup_count != dup_count)
 143         continue;
 144
 145       for (i = 0; i < op_count; i++)
 146         if (p->oplocs[i] != oplocs[i]
 147             && ! (p->oplocs[i] != 0 && oplocs[i] != 0
 148                   && ! strcmp (p->oplocs[i], oplocs[i])))
 149           break;
 150
 151       if (i != op_count)
 152         continue;
 153
 154       for (i = 0; i < dup_count; i++)
 155         if (p->dupnums[i] != dupnums[i]
 156             || strcmp (p->duplocs[i], duplocs[i]))
 157           break;
 158
 159       if (i != dup_count)
 160         continue;
 161
 162       /* This extraction is the same as ours.  Just link us in.  */
 163       link->next = p->insns;
 164       p->insns = link;
 165       return;
 166     }
 167
 168   /* Otherwise, make a new extraction method.  */
 169
 170   p = (struct extraction *) xmalloc (sizeof (struct extraction));
 171   p->op_count = op_count;
 172   p->dup_count = dup_count;
 173   p->next = extractions;
 174   extractions = p;
 175   p->insns = link;
 176   link->next = 0;
 177
 178   for (i = 0; i < op_count; i++)
 179     p->oplocs[i] = oplocs[i];
 180
 181   for (i = 0; i < dup_count; i++)
 182     p->dupnums[i] = dupnums[i], p->duplocs[i] = duplocs[i];
 183 }
 184 \f
 185 static void
 186 walk_rtx (x, path)
 187      rtx x;
 188      const char *path;
 189 {
 190   register RTX_CODE code;
 191   register int i;
 192   register int len;
 193   register char *fmt;
 194   int depth = strlen (path);
 195   char *newpath;
 196
 197   if (x == 0)
 198     return;
 199
 200   code = GET_CODE (x);
 201
 202   switch (code)
 203     {
 204     case PC:
 205     case CC0:
 206     case CONST_INT:
 207     case SYMBOL_REF:
 208       return;
 209
 210     case MATCH_OPERAND:
 211     case MATCH_SCRATCH:
 212       oplocs[XINT (x, 0)] = xstrdup (path);
 213       op_count = MAX (op_count, XINT (x, 0) + 1);
 214       break;
 215
 216     case MATCH_DUP:
 217     case MATCH_PAR_DUP:
 218       duplocs[dup_count] = xstrdup (path);
 219       dupnums[dup_count] = XINT (x, 0);
 220       dup_count++;
 221       break;
 222
 223     case MATCH_OP_DUP:
 224       duplocs[dup_count] = xstrdup (path);
 225       dupnums[dup_count] = XINT (x, 0);
 226       dup_count++;
 227
 228       newpath = (char *) alloca (depth + 2);
 229       strcpy (newpath, path);
 230       newpath[depth + 1] = 0;
 231
 232       for (i = XVECLEN (x, 1) - 1; i >= 0; i--)
 233         {
 234           newpath[depth] = '0' + i;
 235           walk_rtx (XVECEXP (x, 1, i), newpath);
 236         }
 237       return;
 238
 239     case MATCH_OPERATOR:
 240       oplocs[XINT (x, 0)] = xstrdup (path);
 241       op_count = MAX (op_count, XINT (x, 0) + 1);
 242
 243       newpath = (char *) alloca (depth + 2);
 244       strcpy (newpath, path);
 245       newpath[depth + 1] = 0;
 246
 247       for (i = XVECLEN (x, 2) - 1; i >= 0; i--)
 248         {
 249           newpath[depth] = '0' + i;
 250           walk_rtx (XVECEXP (x, 2, i), newpath);
 251         }
 252       return;
 253
 254     case MATCH_PARALLEL:
 255       oplocs[XINT (x, 0)] = xstrdup (path);
 256       op_count = MAX (op_count, XINT (x, 0) + 1);
 257
 258       newpath = (char *) alloca (depth + 2);
 259       strcpy (newpath, path);
 260       newpath[depth + 1] = 0;
 261
 262       for (i = XVECLEN (x, 2) - 1; i >= 0; i--)
 263         {
 264           newpath[depth] = 'a' + i;
 265           walk_rtx (XVECEXP (x, 2, i), newpath);
 266         }
 267       return;
 268
 269     case ADDRESS:
 270       walk_rtx (XEXP (x, 0), path);
 271       return;
 272
 273     default:
 274       break;
 275     }
 276
 277   newpath = (char *) alloca (depth + 2);
 278   strcpy (newpath, path);
 279   newpath[depth + 1] = 0;
 280
 281   fmt = GET_RTX_FORMAT (code);
 282   len = GET_RTX_LENGTH (code);
 283   for (i = 0; i < len; i++)
 284     {
 285       if (fmt[i] == 'e' || fmt[i] == 'u')
 286         {
 287           newpath[depth] = '0' + i;
 288           walk_rtx (XEXP (x, i), newpath);
 289         }
 290       else if (fmt[i] == 'E')
 291         {
 292           int j;
 293           for (j = XVECLEN (x, i) - 1; j >= 0; j--)
 294             {
 295               newpath[depth] = 'a' + j;
 296               walk_rtx (XVECEXP (x, i, j), newpath);
 297             }
 298         }
 299     }
 300 }
 301
 302 /* Given a PATH, representing a path down the instruction's
 303    pattern from the root to a certain point, output code to
 304    evaluate to the rtx at that point.  */
 305
 306 static void
 307 print_path (path)
 308      char *path;
 309 {
 310   register int len = strlen (path);
 311   register int i;
 312
 313   if (len == 0)
 314     {
 315       /* Don't emit "pat", since we may try to take the address of it,
 316          which isn't what is intended.  */
 317       printf("PATTERN (insn)");
 318       return;
 319     }
 320
 321   /* We first write out the operations (XEXP or XVECEXP) in reverse
 322      order, then write "insn", then the indices in forward order.  */
 323
 324   for (i = len - 1; i >=0 ; i--)
 325     {
 326       if (path[i] >= 'a' && path[i] <= 'z')
 327         printf ("XVECEXP (");
 328       else if (path[i] >= '0' && path[i] <= '9')
 329         printf ("XEXP (");
 330       else
 331         abort ();
 332     }
 333
 334   printf ("pat");
 335
 336   for (i = 0; i < len; i++)
 337     {
 338       if (path[i] >= 'a' && path[i] <= 'z')
 339         printf (", 0, %d)", path[i] - 'a');
 340       else if (path[i] >= '0' && path[i] <= '9')
 341         printf (", %d)", path[i] - '0');
 342       else
 343         abort ();
 344     }
 345 }
 346 \f
 347 PTR
 348 xmalloc (size)
 349   size_t size;
 350 {
 351   register PTR val = (PTR) malloc (size);
 352
 353   if (val == 0)
 354     fatal ("virtual memory exhausted");
 355   return val;
 356 }
 357
 358 PTR
 359 xrealloc (ptr, size)
 360   PTR ptr;
 361   size_t size;
 362 {
 363   register PTR result = (PTR) realloc (ptr, size);
 364   if (!result)
 365     fatal ("virtual memory exhausted");
 366   return result;
 367 }
 368
 369 static void
 370 fatal VPROTO ((const char *format, ...))
 371 {
 372 #ifndef ANSI_PROTOTYPES
 373   const char *format;
 374 #endif
 375   va_list ap;
 376
 377   VA_START (ap, format);
 378
 379 #ifndef ANSI_PROTOTYPES
 380   format = va_arg (ap, const char *);
 381 #endif
 382
 383   fprintf (stderr, "genextract: ");
 384   vfprintf (stderr, format, ap);
 385   va_end (ap);
 386   fprintf (stderr, "\n");
 387   exit (FATAL_EXIT_CODE);
 388 }
 389
 390 /* More 'friendly' abort that prints the line and file.
 391    config.h can #define abort fancy_abort if you like that sort of thing.  */
 392
 393 void
 394 fancy_abort ()
 395 {
 396   fatal ("Internal gcc abort.");
 397 }
 398
 399 char *
 400 xstrdup (input)
 401   const char *input;
 402 {
 403   register size_t len = strlen (input) + 1;
 404   register char *output = xmalloc (len);
 405   memcpy (output, input, len);
 406   return output;
 407 }
 408 \f
 409 int
 410 main (argc, argv)
 411      int argc;
 412      char **argv;
 413 {
 414   rtx desc;
 415   FILE *infile;
 416   register int c, i;
 417   struct extraction *p;
 418   struct code_ptr *link;
 419
 420   obstack_init (rtl_obstack);
 421
 422   if (argc <= 1)
 423     fatal ("No input file name.");
 424
 425   infile = fopen (argv[1], "r");
 426   if (infile == 0)
 427     {
 428       perror (argv[1]);
 429       exit (FATAL_EXIT_CODE);
 430     }
 431
 432   init_rtl ();
 433
 434   /* Assign sequential codes to all entries in the machine description
 435      in parallel with the tables in insn-output.c.  */
 436
 437   insn_code_number = 0;
 438
 439   printf ("/* Generated automatically by the program `genextract'\n\
 440 from the machine description file `md'.  */\n\n");
 441
 442   printf ("#include \"config.h\"\n");
 443   printf ("#include \"system.h\"\n");
 444   printf ("#include \"rtl.h\"\n");
 445   printf ("#include \"insn-config.h\"\n");
 446   printf ("#include \"recog.h\"\n");
 447   printf ("#include \"toplev.h\"\n\n");
 448
 449   /* This variable exists only so it can be the "location"
 450      of any missing operand whose numbers are skipped by a given pattern.  */
 451   printf ("static rtx junk ATTRIBUTE_UNUSED;\n");
 452
 453   printf ("void\ninsn_extract (insn)\n");
 454   printf ("     rtx insn;\n");
 455   printf ("{\n");
 456   printf ("  register rtx *ro = recog_operand;\n");
 457   printf ("  register rtx **ro_loc = recog_operand_loc;\n");
 458   printf ("  rtx pat = PATTERN (insn);\n");
 459   printf ("  int i ATTRIBUTE_UNUSED;\n\n");
 460   printf ("  switch (INSN_CODE (insn))\n");
 461   printf ("    {\n");
 462   printf ("    case -1:\n");
 463   printf ("      fatal_insn_not_found (insn);\n\n");
 464
 465   /* Read the machine description.  */
 466
 467   while (1)
 468     {
 469       c = read_skip_spaces (infile);
 470       if (c == EOF)
 471         break;
 472       ungetc (c, infile);
 473
 474       desc = read_rtx (infile);
 475       if (GET_CODE (desc) == DEFINE_INSN)
 476         {
 477           gen_insn (desc);
 478           ++insn_code_number;
 479         }
 480
 481       else if (GET_CODE (desc) == DEFINE_PEEPHOLE)
 482         {
 483           struct code_ptr *link
 484             = (struct code_ptr *) xmalloc (sizeof (struct code_ptr));
 485
 486           link->insn_code = insn_code_number;
 487           link->next = peepholes;
 488           peepholes = link;
 489           ++insn_code_number;
 490         }
 491
 492       else if (GET_CODE (desc) == DEFINE_EXPAND
 493                || GET_CODE (desc) == DEFINE_SPLIT)
 494         ++insn_code_number;
 495     }
 496
 497   /* Write out code to handle peepholes and the insn_codes that it should
 498      be called for.  */
 499   if (peepholes)
 500     {
 501       for (link = peepholes; link; link = link->next)
 502         printf ("    case %d:\n", link->insn_code);
 503
 504       /* The vector in the insn says how many operands it has.
 505          And all it contains are operands.  In fact, the vector was
 506          created just for the sake of this function.  */
 507       printf ("      for (i = XVECLEN (pat, 0) - 1; i >= 0; i--)\n");
 508       printf ("          ro[i] = XVECEXP (pat, 0, i);\n");
 509       printf ("      break;\n\n");
 510     }
 511
 512   /* Write out all the ways to extract insn operands.  */
 513   for (p = extractions; p; p = p->next)
 514     {
 515       for (link = p->insns; link; link = link->next)
 516         printf ("    case %d:\n", link->insn_code);
 517
 518       for (i = 0; i < p->op_count; i++)
 519         {
 520           if (p->oplocs[i] == 0)
 521             {
 522               printf ("      ro[%d] = const0_rtx;\n", i);
 523               printf ("      ro_loc[%d] = &junk;\n", i);
 524             }
 525           else
 526             {
 527               printf ("      ro[%d] = *(ro_loc[%d] = &", i, i);
 528               print_path (p->oplocs[i]);
 529               printf (");\n");
 530             }
 531         }
 532
 533       for (i = 0; i < p->dup_count; i++)
 534         {
 535           printf ("      recog_dup_loc[%d] = &", i);
 536           print_path (p->duplocs[i]);
 537           printf (";\n");
 538           printf ("      recog_dup_num[%d] = %d;\n", i, p->dupnums[i]);
 539         }
 540
 541       printf ("      break;\n\n");
 542     }
 543
 544   /* This should never be reached.  Note that we would also reach this abort
 545    if we tried to extract something whose INSN_CODE was a DEFINE_EXPAND or
 546    DEFINE_SPLIT, but that is correct.  */
 547   printf ("    default:\n      abort ();\n");
 548
 549   printf ("    }\n}\n");
 550
 551   fflush (stdout);
 552   exit (ferror (stdout) != 0 ? FATAL_EXIT_CODE : SUCCESS_EXIT_CODE);
 553   /* NOTREACHED */
 554   return 0;
 555 }