gcc/genextract.c

   1 /* Generate code from machine description to extract operands from insn as rtl.
   2    Copyright (C) 1987, 1991, 1992, 1993, 1997, 1998,
   3    1999, 2000 Free Software Foundation, Inc.
   4
   5 This file is part of GCC.
   6
   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.
  11
  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.
  16
  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.  */
  21
  22
  23 #include "hconfig.h"
  24 #include "system.h"
  25 #include "rtl.h"
  26 #include "errors.h"
  27 #include "insn-config.h"
  28 #include "gensupport.h"
  29
  30
  31 /* This structure contains all the information needed to describe one
  32    set of extractions methods.  Each method may be used by more than
  33    one pattern if the operands are in the same place.
  34
  35    The string for each operand describes that path to the operand and
  36    contains `0' through `9' when going into an expression and `a' through
  37    `z' when going into a vector.  We assume here that only the first operand
  38    of an rtl expression is a vector.  genrecog.c makes the same assumption
  39    (and uses the same representation) and it is currently true.  */
  40
  41 struct extraction
  42 {
  43   int op_count;
  44   char *oplocs[MAX_RECOG_OPERANDS];
  45   int dup_count;
  46   char *duplocs[MAX_DUP_OPERANDS];
  47   int dupnums[MAX_DUP_OPERANDS];
  48   struct code_ptr *insns;
  49   struct extraction *next;
  50 };
  51
  52 /* Holds a single insn code that use an extraction method.  */
  53
  54 struct code_ptr
  55 {
  56   int insn_code;
  57   struct code_ptr *next;
  58 };
  59
  60 static struct extraction *extractions;
  61
  62 /* Holds an array of names indexed by insn_code_number.  */
  63 static char **insn_name_ptr = 0;
  64 static int insn_name_ptr_size = 0;
  65
  66 /* Number instruction patterns handled, starting at 0 for first one.  */
  67
  68 static int insn_code_number;
  69
  70 /* Records the large operand number in this insn.  */
  71
  72 static int op_count;
  73
  74 /* Records the location of any operands using the string format described
  75    above.  */
  76
  77 static char *oplocs[MAX_RECOG_OPERANDS];
  78
  79 /* Number the occurrences of MATCH_DUP in each instruction,
  80    starting at 0 for the first occurrence.  */
  81
  82 static int dup_count;
  83
  84 /* Records the location of any MATCH_DUP operands.  */
  85
  86 static char *duplocs[MAX_DUP_OPERANDS];
  87
  88 /* Record the operand number of any MATCH_DUPs.  */
  89
  90 static int dupnums[MAX_DUP_OPERANDS];
  91
  92 /* Record the list of insn_codes for peepholes.  */
  93
  94 static struct code_ptr *peepholes;
  95
  96 static void gen_insn PARAMS ((rtx));
  97 static void walk_rtx PARAMS ((rtx, const char *));
  98 static void print_path PARAMS ((const char *));
  99 static void record_insn_name PARAMS ((int, const char *));
 100
 101 static void
 102 gen_insn (insn)
 103      rtx insn;
 104 {
 105   int i;
 106   struct extraction *p;
 107   struct code_ptr *link;
 108
 109   op_count = 0;
 110   dup_count = 0;
 111
 112   /* No operands seen so far in this pattern.  */
 113   memset (oplocs, 0, sizeof oplocs);
 114
 115   /* Walk the insn's pattern, remembering at all times the path
 116      down to the walking point.  */
 117
 118   if (XVECLEN (insn, 1) == 1)
 119     walk_rtx (XVECEXP (insn, 1, 0), "");
 120   else
 121     for (i = XVECLEN (insn, 1) - 1; i >= 0; i--)
 122       {
 123         char path[2];
 124
 125         path[0] = 'a' + i;
 126         path[1] = 0;
 127
 128         walk_rtx (XVECEXP (insn, 1, i), path);
 129       }
 130
 131   link = (struct code_ptr *) xmalloc (sizeof (struct code_ptr));
 132   link->insn_code = insn_code_number;
 133
 134   /* See if we find something that already had this extraction method.  */
 135
 136   for (p = extractions; p; p = p->next)
 137     {
 138       if (p->op_count != op_count || p->dup_count != dup_count)
 139         continue;
 140
 141       for (i = 0; i < op_count; i++)
 142         if (p->oplocs[i] != oplocs[i]
 143             && ! (p->oplocs[i] != 0 && oplocs[i] != 0
 144                   && ! strcmp (p->oplocs[i], oplocs[i])))
 145           break;
 146
 147       if (i != op_count)
 148         continue;
 149
 150       for (i = 0; i < dup_count; i++)
 151         if (p->dupnums[i] != dupnums[i]
 152             || strcmp (p->duplocs[i], duplocs[i]))
 153           break;
 154
 155       if (i != dup_count)
 156         continue;
 157
 158       /* This extraction is the same as ours.  Just link us in.  */
 159       link->next = p->insns;
 160       p->insns = link;
 161       return;
 162     }
 163
 164   /* Otherwise, make a new extraction method.  */
 165
 166   p = (struct extraction *) xmalloc (sizeof (struct extraction));
 167   p->op_count = op_count;
 168   p->dup_count = dup_count;
 169   p->next = extractions;
 170   extractions = p;
 171   p->insns = link;
 172   link->next = 0;
 173
 174   for (i = 0; i < op_count; i++)
 175     p->oplocs[i] = oplocs[i];
 176
 177   for (i = 0; i < dup_count; i++)
 178     p->dupnums[i] = dupnums[i], p->duplocs[i] = duplocs[i];
 179 }
 180 \f
 181 static void
 182 walk_rtx (x, path)
 183      rtx x;
 184      const char *path;
 185 {
 186   RTX_CODE code;
 187   int i;
 188   int len;
 189   const char *fmt;
 190   int depth = strlen (path);
 191   char *newpath;
 192
 193   if (x == 0)
 194     return;
 195
 196   code = GET_CODE (x);
 197
 198   switch (code)
 199     {
 200     case PC:
 201     case CC0:
 202     case CONST_INT:
 203     case SYMBOL_REF:
 204       return;
 205
 206     case MATCH_OPERAND:
 207     case MATCH_SCRATCH:
 208       oplocs[XINT (x, 0)] = xstrdup (path);
 209       op_count = MAX (op_count, XINT (x, 0) + 1);
 210       break;
 211
 212     case MATCH_DUP:
 213     case MATCH_PAR_DUP:
 214       duplocs[dup_count] = xstrdup (path);
 215       dupnums[dup_count] = XINT (x, 0);
 216       dup_count++;
 217       break;
 218
 219     case MATCH_OP_DUP:
 220       duplocs[dup_count] = xstrdup (path);
 221       dupnums[dup_count] = XINT (x, 0);
 222       dup_count++;
 223
 224       newpath = (char *) xmalloc (depth + 2);
 225       strcpy (newpath, path);
 226       newpath[depth + 1] = 0;
 227
 228       for (i = XVECLEN (x, 1) - 1; i >= 0; i--)
 229         {
 230           newpath[depth] = '0' + i;
 231           walk_rtx (XVECEXP (x, 1, i), newpath);
 232         }
 233       free (newpath);
 234       return;
 235
 236     case MATCH_OPERATOR:
 237       oplocs[XINT (x, 0)] = xstrdup (path);
 238       op_count = MAX (op_count, XINT (x, 0) + 1);
 239
 240       newpath = (char *) xmalloc (depth + 2);
 241       strcpy (newpath, path);
 242       newpath[depth + 1] = 0;
 243
 244       for (i = XVECLEN (x, 2) - 1; i >= 0; i--)
 245         {
 246           newpath[depth] = '0' + i;
 247           walk_rtx (XVECEXP (x, 2, i), newpath);
 248         }
 249       free (newpath);
 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 *) xmalloc (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       free (newpath);
 266       return;
 267
 268     case ADDRESS:
 269       walk_rtx (XEXP (x, 0), path);
 270       return;
 271
 272     default:
 273       break;
 274     }
 275
 276   newpath = (char *) xmalloc (depth + 2);
 277   strcpy (newpath, path);
 278   newpath[depth + 1] = 0;
 279
 280   fmt = GET_RTX_FORMAT (code);
 281   len = GET_RTX_LENGTH (code);
 282   for (i = 0; i < len; i++)
 283     {
 284       if (fmt[i] == 'e' || fmt[i] == 'u')
 285         {
 286           newpath[depth] = '0' + i;
 287           walk_rtx (XEXP (x, i), newpath);
 288         }
 289       else if (fmt[i] == 'E')
 290         {
 291           int j;
 292           for (j = XVECLEN (x, i) - 1; j >= 0; j--)
 293             {
 294               newpath[depth] = 'a' + j;
 295               walk_rtx (XVECEXP (x, i, j), newpath);
 296             }
 297         }
 298     }
 299   free (newpath);
 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      const char *path;
 309 {
 310   int len = strlen (path);
 311   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 (ISLOWER(path[i]))
 327         printf ("XVECEXP (");
 328       else if (ISDIGIT(path[i]))
 329         printf ("XEXP (");
 330       else
 331         abort ();
 332     }
 333
 334   printf ("pat");
 335
 336   for (i = 0; i < len; i++)
 337     {
 338       if (ISLOWER(path[i]))
 339         printf (", 0, %d)", path[i] - 'a');
 340       else if (ISDIGIT(path[i]))
 341         printf (", %d)", path[i] - '0');
 342       else
 343         abort ();
 344     }
 345 }
 346 \f
 347 extern int main PARAMS ((int, char **));
 348
 349 int
 350 main (argc, argv)
 351      int argc;
 352      char **argv;
 353 {
 354   rtx desc;
 355   int i;
 356   struct extraction *p;
 357   struct code_ptr *link;
 358   const char *name;
 359
 360   progname = "genextract";
 361
 362   if (argc <= 1)
 363     fatal ("No input file name.");
 364
 365   if (init_md_reader (argv[1]) != SUCCESS_EXIT_CODE)
 366     return (FATAL_EXIT_CODE);
 367
 368   /* Assign sequential codes to all entries in the machine description
 369      in parallel with the tables in insn-output.c.  */
 370
 371   insn_code_number = 0;
 372
 373   printf ("/* Generated automatically by the program `genextract'\n\
 374 from the machine description file `md'.  */\n\n");
 375
 376   printf ("#include \"config.h\"\n");
 377   printf ("#include \"system.h\"\n");
 378   printf ("#include \"rtl.h\"\n");
 379   printf ("#include \"insn-config.h\"\n");
 380   printf ("#include \"recog.h\"\n");
 381   printf ("#include \"toplev.h\"\n\n");
 382
 383   /* This variable exists only so it can be the "location"
 384      of any missing operand whose numbers are skipped by a given pattern.  */
 385   printf ("static rtx junk ATTRIBUTE_UNUSED;\n");
 386
 387   printf ("void\ninsn_extract (insn)\n");
 388   printf ("     rtx insn;\n");
 389   printf ("{\n");
 390   printf ("  rtx *ro = recog_data.operand;\n");
 391   printf ("  rtx **ro_loc = recog_data.operand_loc;\n");
 392   printf ("  rtx pat = PATTERN (insn);\n");
 393   printf ("  int i ATTRIBUTE_UNUSED;\n\n");
 394   printf ("  memset (ro, 0, sizeof (*ro) * MAX_RECOG_OPERANDS);\n");
 395   printf ("  memset (ro_loc, 0, sizeof (*ro_loc) * MAX_RECOG_OPERANDS);\n");
 396   printf ("  switch (INSN_CODE (insn))\n");
 397   printf ("    {\n");
 398   printf ("    case -1:\n");
 399   printf ("      fatal_insn_not_found (insn);\n\n");
 400
 401   /* Read the machine description.  */
 402
 403   while (1)
 404     {
 405       int line_no;
 406
 407       desc = read_md_rtx (&line_no, &insn_code_number);
 408       if (desc == NULL)
 409         break;
 410
 411        if (GET_CODE (desc) == DEFINE_INSN)
 412         {
 413           record_insn_name (insn_code_number, XSTR (desc, 0));
 414           gen_insn (desc);
 415         }
 416
 417       else if (GET_CODE (desc) == DEFINE_PEEPHOLE)
 418         {
 419           struct code_ptr *link
 420             = (struct code_ptr *) xmalloc (sizeof (struct code_ptr));
 421
 422           link->insn_code = insn_code_number;
 423           link->next = peepholes;
 424           peepholes = link;
 425         }
 426     }
 427
 428   /* Write out code to handle peepholes and the insn_codes that it should
 429      be called for.  */
 430   if (peepholes)
 431     {
 432       for (link = peepholes; link; link = link->next)
 433         printf ("    case %d:\n", link->insn_code);
 434
 435       /* The vector in the insn says how many operands it has.
 436          And all it contains are operands.  In fact, the vector was
 437          created just for the sake of this function.  */
 438       printf ("      for (i = XVECLEN (pat, 0) - 1; i >= 0; i--)\n");
 439       printf ("          ro[i] = XVECEXP (pat, 0, i);\n");
 440       printf ("      break;\n\n");
 441     }
 442
 443   /* Write out all the ways to extract insn operands.  */
 444   for (p = extractions; p; p = p->next)
 445     {
 446       for (link = p->insns; link; link = link->next)
 447         {
 448           i = link->insn_code;
 449           name = get_insn_name (i);
 450           if (name)
 451             printf ("    case %d:  /* %s */\n", i, name);
 452           else
 453             printf ("    case %d:\n", i);
 454         }
 455
 456       for (i = 0; i < p->op_count; i++)
 457         {
 458           if (p->oplocs[i] == 0)
 459             {
 460               printf ("      ro[%d] = const0_rtx;\n", i);
 461               printf ("      ro_loc[%d] = &junk;\n", i);
 462             }
 463           else
 464             {
 465               printf ("      ro[%d] = *(ro_loc[%d] = &", i, i);
 466               print_path (p->oplocs[i]);
 467               printf (");\n");
 468             }
 469         }
 470
 471       for (i = 0; i < p->dup_count; i++)
 472         {
 473           printf ("      recog_data.dup_loc[%d] = &", i);
 474           print_path (p->duplocs[i]);
 475           printf (";\n");
 476           printf ("      recog_data.dup_num[%d] = %d;\n", i, p->dupnums[i]);
 477         }
 478
 479       printf ("      break;\n\n");
 480     }
 481
 482   /* This should never be reached.  Note that we would also reach this abort
 483    if we tried to extract something whose INSN_CODE was a DEFINE_EXPAND or
 484    DEFINE_SPLIT, but that is correct.  */
 485   printf ("    default:\n      abort ();\n");
 486
 487   printf ("    }\n}\n");
 488
 489   fflush (stdout);
 490   return (ferror (stdout) != 0 ? FATAL_EXIT_CODE : SUCCESS_EXIT_CODE);
 491 }
 492
 493 /* Define this so we can link with print-rtl.o to get debug_rtx function.  */
 494 const char *
 495 get_insn_name (code)
 496      int code ATTRIBUTE_UNUSED;
 497 {
 498   if (code < insn_name_ptr_size)
 499     return insn_name_ptr[code];
 500   else
 501     return NULL;
 502 }
 503
 504 static void
 505 record_insn_name (code, name)
 506      int code;
 507      const char *name;
 508 {
 509   static const char *last_real_name = "insn";
 510   static int last_real_code = 0;
 511   char *new;
 512
 513   if (insn_name_ptr_size <= code)
 514     {
 515       int new_size;
 516       new_size = (insn_name_ptr_size ? insn_name_ptr_size * 2 : 512);
 517       insn_name_ptr =
 518         (char **) xrealloc (insn_name_ptr, sizeof(char *) * new_size);
 519       memset (insn_name_ptr + insn_name_ptr_size, 0,
 520               sizeof(char *) * (new_size - insn_name_ptr_size));
 521       insn_name_ptr_size = new_size;
 522     }
 523
 524   if (!name || name[0] == '\0')
 525     {
 526       new = xmalloc (strlen (last_real_name) + 10);
 527       sprintf (new, "%s+%d", last_real_name, code - last_real_code);
 528     }
 529   else
 530     {
 531       last_real_name = new = xstrdup (name);
 532       last_real_code = code;
 533     }
 534
 535   insn_name_ptr[code] = new;
 536 }