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