gcc/genemit.c

   1 /* Generate code from machine description to emit insns as rtl.
   2    Copyright (C) 1987, 1988, 1991, 1994, 1995, 1997, 1998, 1999, 2000
   3    Free Software Foundation, Inc.
   4
   5 This file is part of GNU CC.
   6
   7 GNU CC is free software; you can redistribute it and/or modify
   8 it under the terms of the GNU General Public License as published by
   9 the Free Software Foundation; either version 2, or (at your option)
  10 any later version.
  11
  12 GNU CC is distributed in the hope that it will be useful,
  13 but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 GNU General Public License for more details.
  16
  17 You should have received a copy of the GNU General Public License
  18 along with GNU CC; see the file COPYING.  If not, write to
  19 the Free Software Foundation, 59 Temple Place - Suite 330,
  20 Boston, MA 02111-1307, USA.  */
  21
  22
  23 #include "hconfig.h"
  24 #include "system.h"
  25 #include "rtl.h"
  26 #include "errors.h"
  27 #include "gensupport.h"
  28
  29
  30 static int max_opno;
  31 static int max_dup_opno;
  32 static int max_scratch_opno;
  33 static int register_constraints;
  34 static int insn_code_number;
  35 static int insn_index_number;
  36
  37 /* Data structure for recording the patterns of insns that have CLOBBERs.
  38    We use this to output a function that adds these CLOBBERs to a
  39    previously-allocated PARALLEL expression.  */
  40
  41 struct clobber_pat
  42 {
  43   struct clobber_ent *insns;
  44   rtx pattern;
  45   int first_clobber;
  46   struct clobber_pat *next;
  47 } *clobber_list;
  48
  49 /* Records one insn that uses the clobber list.  */
  50
  51 struct clobber_ent
  52 {
  53   int code_number;              /* Counts only insns.  */
  54   struct clobber_ent *next;
  55 };
  56
  57 static void max_operand_1               PARAMS ((rtx));
  58 static int max_operand_vec              PARAMS ((rtx, int));
  59 static void print_code                  PARAMS ((RTX_CODE));
  60 static void gen_exp                     PARAMS ((rtx, enum rtx_code));
  61 static void gen_insn                    PARAMS ((rtx));
  62 static void gen_expand                  PARAMS ((rtx));
  63 static void gen_split                   PARAMS ((rtx));
  64 static void output_add_clobbers         PARAMS ((void));
  65 static void gen_rtx_scratch             PARAMS ((rtx, enum rtx_code));
  66 static void output_peephole2_scratches  PARAMS ((rtx));
  67
  68 \f
  69 static void
  70 max_operand_1 (x)
  71      rtx x;
  72 {
  73   register RTX_CODE code;
  74   register int i;
  75   register int len;
  76   register const char *fmt;
  77
  78   if (x == 0)
  79     return;
  80
  81   code = GET_CODE (x);
  82
  83   if (code == MATCH_OPERAND && XSTR (x, 2) != 0 && *XSTR (x, 2) != '\0')
  84     register_constraints = 1;
  85   if (code == MATCH_SCRATCH && XSTR (x, 1) != 0 && *XSTR (x, 1) != '\0')
  86     register_constraints = 1;
  87   if (code == MATCH_OPERAND || code == MATCH_OPERATOR
  88       || code == MATCH_PARALLEL)
  89     max_opno = MAX (max_opno, XINT (x, 0));
  90   if (code == MATCH_DUP || code == MATCH_OP_DUP || code == MATCH_PAR_DUP)
  91     max_dup_opno = MAX (max_dup_opno, XINT (x, 0));
  92   if (code == MATCH_SCRATCH)
  93     max_scratch_opno = MAX (max_scratch_opno, XINT (x, 0));
  94
  95   fmt = GET_RTX_FORMAT (code);
  96   len = GET_RTX_LENGTH (code);
  97   for (i = 0; i < len; i++)
  98     {
  99       if (fmt[i] == 'e' || fmt[i] == 'u')
 100         max_operand_1 (XEXP (x, i));
 101       else if (fmt[i] == 'E')
 102         {
 103           int j;
 104           for (j = 0; j < XVECLEN (x, i); j++)
 105             max_operand_1 (XVECEXP (x, i, j));
 106         }
 107     }
 108 }
 109
 110 static int
 111 max_operand_vec (insn, arg)
 112      rtx insn;
 113      int arg;
 114 {
 115   register int len = XVECLEN (insn, arg);
 116   register int i;
 117
 118   max_opno = -1;
 119   max_dup_opno = -1;
 120   max_scratch_opno = -1;
 121
 122   for (i = 0; i < len; i++)
 123     max_operand_1 (XVECEXP (insn, arg, i));
 124
 125   return max_opno + 1;
 126 }
 127 \f
 128 static void
 129 print_code (code)
 130      RTX_CODE code;
 131 {
 132   register const char *p1;
 133   for (p1 = GET_RTX_NAME (code); *p1; p1++)
 134     putchar (TOUPPER(*p1));
 135 }
 136
 137 static void
 138 gen_rtx_scratch (x, subroutine_type)
 139      rtx x;
 140      enum rtx_code subroutine_type;
 141 {
 142   if (subroutine_type == DEFINE_PEEPHOLE2)
 143     {
 144       printf ("operand%d", XINT (x, 0));
 145     }
 146   else
 147     {
 148       printf ("gen_rtx_SCRATCH (%smode)", GET_MODE_NAME (GET_MODE (x)));
 149     }
 150 }
 151
 152 /* Print a C expression to construct an RTX just like X,
 153    substituting any operand references appearing within.  */
 154
 155 static void
 156 gen_exp (x, subroutine_type)
 157      rtx x;
 158      enum rtx_code subroutine_type;
 159 {
 160   register RTX_CODE code;
 161   register int i;
 162   register int len;
 163   register const char *fmt;
 164
 165   if (x == 0)
 166     {
 167       printf ("NULL_RTX");
 168       return;
 169     }
 170
 171   code = GET_CODE (x);
 172
 173   switch (code)
 174     {
 175     case MATCH_OPERAND:
 176     case MATCH_DUP:
 177       printf ("operand%d", XINT (x, 0));
 178       return;
 179
 180     case MATCH_OP_DUP:
 181       printf ("gen_rtx (GET_CODE (operand%d), ", XINT (x, 0));
 182       if (GET_MODE (x) == VOIDmode)
 183         printf ("GET_MODE (operand%d)", XINT (x, 0));
 184       else
 185         printf ("%smode", GET_MODE_NAME (GET_MODE (x)));
 186       for (i = 0; i < XVECLEN (x, 1); i++)
 187         {
 188           printf (",\n\t\t");
 189           gen_exp (XVECEXP (x, 1, i), subroutine_type);
 190         }
 191       printf (")");
 192       return;
 193
 194     case MATCH_OPERATOR:
 195       printf ("gen_rtx (GET_CODE (operand%d)", XINT (x, 0));
 196       printf (", %smode", GET_MODE_NAME (GET_MODE (x)));
 197       for (i = 0; i < XVECLEN (x, 2); i++)
 198         {
 199           printf (",\n\t\t");
 200           gen_exp (XVECEXP (x, 2, i), subroutine_type);
 201         }
 202       printf (")");
 203       return;
 204
 205     case MATCH_PARALLEL:
 206     case MATCH_PAR_DUP:
 207       printf ("operand%d", XINT (x, 0));
 208       return;
 209
 210     case MATCH_SCRATCH:
 211       gen_rtx_scratch (x, subroutine_type);
 212       return;
 213
 214     case ADDRESS:
 215       fatal ("ADDRESS expression code used in named instruction pattern");
 216
 217     case PC:
 218       printf ("pc_rtx");
 219       return;
 220
 221     case CC0:
 222       printf ("cc0_rtx");
 223       return;
 224
 225     case CONST_INT:
 226       if (INTVAL (x) == 0)
 227         printf ("const0_rtx");
 228       else if (INTVAL (x) == 1)
 229         printf ("const1_rtx");
 230       else if (INTVAL (x) == -1)
 231         printf ("constm1_rtx");
 232       else if (INTVAL (x) == STORE_FLAG_VALUE)
 233         printf ("const_true_rtx");
 234       else
 235         {
 236           printf ("GEN_INT (");
 237           printf (HOST_WIDE_INT_PRINT_DEC, INTVAL (x));
 238           printf (")");
 239         }
 240       return;
 241
 242     case CONST_DOUBLE:
 243       /* These shouldn't be written in MD files.  Instead, the appropriate
 244          routines in varasm.c should be called.  */
 245       abort ();
 246
 247     default:
 248       break;
 249     }
 250
 251   printf ("gen_rtx_");
 252   print_code (code);
 253   printf (" (%smode", GET_MODE_NAME (GET_MODE (x)));
 254
 255   fmt = GET_RTX_FORMAT (code);
 256   len = GET_RTX_LENGTH (code);
 257   for (i = 0; i < len; i++)
 258     {
 259       if (fmt[i] == '0')
 260         break;
 261       printf (",\n\t");
 262       if (fmt[i] == 'e' || fmt[i] == 'u')
 263         gen_exp (XEXP (x, i), subroutine_type);
 264       else if (fmt[i] == 'i')
 265         printf ("%u", XINT (x, i));
 266       else if (fmt[i] == 's')
 267         printf ("\"%s\"", XSTR (x, i));
 268       else if (fmt[i] == 'E')
 269         {
 270           int j;
 271           printf ("gen_rtvec (%d", XVECLEN (x, i));
 272           for (j = 0; j < XVECLEN (x, i); j++)
 273             {
 274               printf (",\n\t\t");
 275               gen_exp (XVECEXP (x, i, j), subroutine_type);
 276             }
 277           printf (")");
 278         }
 279       else
 280         abort ();
 281     }
 282   printf (")");
 283 }
 284 \f
 285 /* Generate the `gen_...' function for a DEFINE_INSN.  */
 286
 287 static void
 288 gen_insn (insn)
 289      rtx insn;
 290 {
 291   int operands;
 292   register int i;
 293
 294   /* See if the pattern for this insn ends with a group of CLOBBERs of (hard)
 295      registers or MATCH_SCRATCHes.  If so, store away the information for
 296      later.  */
 297
 298   if (XVEC (insn, 1))
 299     {
 300       for (i = XVECLEN (insn, 1) - 1; i > 0; i--)
 301         if (GET_CODE (XVECEXP (insn, 1, i)) != CLOBBER
 302             || (GET_CODE (XEXP (XVECEXP (insn, 1, i), 0)) != REG
 303                 && GET_CODE (XEXP (XVECEXP (insn, 1, i), 0)) != MATCH_SCRATCH))
 304           break;
 305
 306       if (i != XVECLEN (insn, 1) - 1)
 307         {
 308           register struct clobber_pat *p;
 309           register struct clobber_ent *link
 310             = (struct clobber_ent *) xmalloc (sizeof (struct clobber_ent));
 311           register int j;
 312
 313           link->code_number = insn_code_number;
 314
 315           /* See if any previous CLOBBER_LIST entry is the same as this
 316              one.  */
 317
 318           for (p = clobber_list; p; p = p->next)
 319             {
 320               if (p->first_clobber != i + 1
 321                   || XVECLEN (p->pattern, 1) != XVECLEN (insn, 1))
 322                 continue;
 323
 324               for (j = i + 1; j < XVECLEN (insn, 1); j++)
 325                 {
 326                   rtx old = XEXP (XVECEXP (p->pattern, 1, j), 0);
 327                   rtx new = XEXP (XVECEXP (insn, 1, j), 0);
 328
 329                   /* OLD and NEW are the same if both are to be a SCRATCH
 330                      of the same mode,
 331                      or if both are registers of the same mode and number.  */
 332                   if (! (GET_MODE (old) == GET_MODE (new)
 333                          && ((GET_CODE (old) == MATCH_SCRATCH
 334                               && GET_CODE (new) == MATCH_SCRATCH)
 335                              || (GET_CODE (old) == REG && GET_CODE (new) == REG
 336                                  && REGNO (old) == REGNO (new)))))
 337                     break;
 338                 }
 339
 340               if (j == XVECLEN (insn, 1))
 341                 break;
 342             }
 343
 344           if (p == 0)
 345             {
 346               p = (struct clobber_pat *) xmalloc (sizeof (struct clobber_pat));
 347
 348               p->insns = 0;
 349               p->pattern = insn;
 350               p->first_clobber = i + 1;
 351               p->next = clobber_list;
 352               clobber_list = p;
 353             }
 354
 355           link->next = p->insns;
 356           p->insns = link;
 357         }
 358     }
 359
 360   /* Don't mention instructions whose names are the null string
 361      or begin with '*'.  They are in the machine description just
 362      to be recognized.  */
 363   if (XSTR (insn, 0)[0] == 0 || XSTR (insn, 0)[0] == '*')
 364     return;
 365
 366   /* Find out how many operands this function has,
 367      and also whether any of them have register constraints.  */
 368   register_constraints = 0;
 369   operands = max_operand_vec (insn, 1);
 370   if (max_dup_opno >= operands)
 371     fatal ("match_dup operand number has no match_operand");
 372
 373   /* Output the function name and argument declarations.  */
 374   printf ("rtx\ngen_%s (", XSTR (insn, 0));
 375   for (i = 0; i < operands; i++)
 376     if (i)
 377       printf (", operand%d", i);
 378     else
 379       printf ("operand%d", i);
 380   printf (")\n");
 381   for (i = 0; i < operands; i++)
 382     printf ("     rtx operand%d;\n", i);
 383   printf ("{\n");
 384
 385   /* Output code to construct and return the rtl for the instruction body */
 386
 387   if (XVECLEN (insn, 1) == 1)
 388     {
 389       printf ("  return ");
 390       gen_exp (XVECEXP (insn, 1, 0), DEFINE_INSN);
 391       printf (";\n}\n\n");
 392     }
 393   else
 394     {
 395       printf ("  return gen_rtx_PARALLEL (VOIDmode, gen_rtvec (%d",
 396               XVECLEN (insn, 1));
 397
 398       for (i = 0; i < XVECLEN (insn, 1); i++)
 399         {
 400           printf (",\n\t\t");
 401           gen_exp (XVECEXP (insn, 1, i), DEFINE_INSN);
 402         }
 403       printf ("));\n}\n\n");
 404     }
 405 }
 406 \f
 407 /* Generate the `gen_...' function for a DEFINE_EXPAND.  */
 408
 409 static void
 410 gen_expand (expand)
 411      rtx expand;
 412 {
 413   int operands;
 414   register int i;
 415
 416   if (strlen (XSTR (expand, 0)) == 0)
 417     fatal ("define_expand lacks a name");
 418   if (XVEC (expand, 1) == 0)
 419     fatal ("define_expand for %s lacks a pattern", XSTR (expand, 0));
 420
 421   /* Find out how many operands this function has,
 422      and also whether any of them have register constraints.  */
 423   register_constraints = 0;
 424
 425   operands = max_operand_vec (expand, 1);
 426
 427   /* Output the function name and argument declarations.  */
 428   printf ("rtx\ngen_%s (", XSTR (expand, 0));
 429   for (i = 0; i < operands; i++)
 430     if (i)
 431       printf (", operand%d", i);
 432     else
 433       printf ("operand%d", i);
 434   printf (")\n");
 435   for (i = 0; i < operands; i++)
 436     printf ("     rtx operand%d;\n", i);
 437   printf ("{\n");
 438
 439   /* If we don't have any C code to write, only one insn is being written,
 440      and no MATCH_DUPs are present, we can just return the desired insn
 441      like we do for a DEFINE_INSN.  This saves memory.  */
 442   if ((XSTR (expand, 3) == 0 || *XSTR (expand, 3) == '\0')
 443       && operands > max_dup_opno
 444       && XVECLEN (expand, 1) == 1)
 445     {
 446       printf ("  return ");
 447       gen_exp (XVECEXP (expand, 1, 0), DEFINE_EXPAND);
 448       printf (";\n}\n\n");
 449       return;
 450     }
 451
 452   /* For each operand referred to only with MATCH_DUPs,
 453      make a local variable.  */
 454   for (i = operands; i <= max_dup_opno; i++)
 455     printf ("  rtx operand%d;\n", i);
 456   for (; i <= max_scratch_opno; i++)
 457     printf ("  rtx operand%d;\n", i);
 458   printf ("  rtx _val = 0;\n");
 459   printf ("  start_sequence ();\n");
 460
 461   /* The fourth operand of DEFINE_EXPAND is some code to be executed
 462      before the actual construction.
 463      This code expects to refer to `operands'
 464      just as the output-code in a DEFINE_INSN does,
 465      but here `operands' is an automatic array.
 466      So copy the operand values there before executing it.  */
 467   if (XSTR (expand, 3) && *XSTR (expand, 3))
 468     {
 469       printf ("  {\n");
 470       if (operands > 0 || max_dup_opno >= 0 || max_scratch_opno >= 0)
 471         printf ("    rtx operands[%d];\n",
 472             MAX (operands, MAX (max_scratch_opno, max_dup_opno) + 1));
 473       /* Output code to copy the arguments into `operands'.  */
 474       for (i = 0; i < operands; i++)
 475         printf ("    operands[%d] = operand%d;\n", i, i);
 476
 477       /* Output the special code to be executed before the sequence
 478          is generated.  */
 479       printf ("%s\n", XSTR (expand, 3));
 480
 481       /* Output code to copy the arguments back out of `operands'
 482          (unless we aren't going to use them at all).  */
 483       if (XVEC (expand, 1) != 0)
 484         {
 485           for (i = 0; i < operands; i++)
 486             printf ("    operand%d = operands[%d];\n", i, i);
 487           for (; i <= max_dup_opno; i++)
 488             printf ("    operand%d = operands[%d];\n", i, i);
 489           for (; i <= max_scratch_opno; i++)
 490             printf ("    operand%d = operands[%d];\n", i, i);
 491         }
 492       printf ("  }\n");
 493     }
 494
 495   /* Output code to construct the rtl for the instruction bodies.
 496      Use emit_insn to add them to the sequence being accumulated.
 497      But don't do this if the user's code has set `no_more' nonzero.  */
 498
 499   for (i = 0; i < XVECLEN (expand, 1); i++)
 500     {
 501       rtx next = XVECEXP (expand, 1, i);
 502       if ((GET_CODE (next) == SET && GET_CODE (SET_DEST (next)) == PC)
 503           || (GET_CODE (next) == PARALLEL
 504               && GET_CODE (XVECEXP (next, 0, 0)) == SET
 505               && GET_CODE (SET_DEST (XVECEXP (next, 0, 0))) == PC)
 506           || GET_CODE (next) == RETURN)
 507         printf ("  emit_jump_insn (");
 508       else if ((GET_CODE (next) == SET && GET_CODE (SET_SRC (next)) == CALL)
 509                || GET_CODE (next) == CALL
 510                || (GET_CODE (next) == PARALLEL
 511                    && GET_CODE (XVECEXP (next, 0, 0)) == SET
 512                    && GET_CODE (SET_SRC (XVECEXP (next, 0, 0))) == CALL)
 513                || (GET_CODE (next) == PARALLEL
 514                    && GET_CODE (XVECEXP (next, 0, 0)) == CALL))
 515         printf ("  emit_call_insn (");
 516       else if (GET_CODE (next) == CODE_LABEL)
 517         printf ("  emit_label (");
 518       else if (GET_CODE (next) == MATCH_OPERAND
 519                || GET_CODE (next) == MATCH_DUP
 520                || GET_CODE (next) == MATCH_OPERATOR
 521                || GET_CODE (next) == MATCH_OP_DUP
 522                || GET_CODE (next) == MATCH_PARALLEL
 523                || GET_CODE (next) == MATCH_PAR_DUP
 524                || GET_CODE (next) == PARALLEL)
 525         printf ("  emit (");
 526       else
 527         printf ("  emit_insn (");
 528       gen_exp (next, DEFINE_EXPAND);
 529       printf (");\n");
 530       if (GET_CODE (next) == SET && GET_CODE (SET_DEST (next)) == PC
 531           && GET_CODE (SET_SRC (next)) == LABEL_REF)
 532         printf ("  emit_barrier ();");
 533     }
 534
 535   /* Call `gen_sequence' to make a SEQUENCE out of all the
 536      insns emitted within this gen_... function.  */
 537
 538   printf ("  _val = gen_sequence ();\n");
 539   printf ("  end_sequence ();\n");
 540   printf ("  return _val;\n}\n\n");
 541 }
 542
 543 /* Like gen_expand, but generates a SEQUENCE.  */
 544
 545 static void
 546 gen_split (split)
 547      rtx split;
 548 {
 549   register int i;
 550   int operands;
 551   const char *name = "split";
 552
 553   if (GET_CODE (split) == DEFINE_PEEPHOLE2)
 554     name = "peephole2";
 555
 556   if (XVEC (split, 0) == 0)
 557     fatal ("define_%s (definition %d) lacks a pattern", name,
 558            insn_index_number);
 559   else if (XVEC (split, 2) == 0)
 560     fatal ("define_%s (definition %d) lacks a replacement pattern", name,
 561            insn_index_number);
 562
 563   /* Find out how many operands this function has.  */
 564
 565   max_operand_vec (split, 2);
 566   operands = MAX (max_opno, MAX (max_dup_opno, max_scratch_opno)) + 1;
 567
 568   /* Output the prototype, function name and argument declarations.  */
 569   if (GET_CODE (split) == DEFINE_PEEPHOLE2)
 570     {
 571       printf ("extern rtx gen_%s_%d PARAMS ((rtx, rtx *));\n",
 572               name, insn_code_number);
 573       printf ("rtx\ngen_%s_%d (curr_insn, operands)\n\
 574      rtx curr_insn ATTRIBUTE_UNUSED;\n\
 575      rtx *operands;\n",
 576               name, insn_code_number);
 577     }
 578   else
 579     {
 580       printf ("extern rtx gen_split_%d PARAMS ((rtx *));\n", insn_code_number);
 581       printf ("rtx\ngen_%s_%d (operands)\n     rtx *operands;\n", name,
 582               insn_code_number);
 583     }
 584   printf ("{\n");
 585
 586   /* Declare all local variables.  */
 587   for (i = 0; i < operands; i++)
 588     printf ("  rtx operand%d;\n", i);
 589   printf ("  rtx _val = 0;\n");
 590
 591   if (GET_CODE (split) == DEFINE_PEEPHOLE2)
 592     output_peephole2_scratches (split);
 593
 594   printf ("  start_sequence ();\n");
 595
 596   /* The fourth operand of DEFINE_SPLIT is some code to be executed
 597      before the actual construction.  */
 598
 599   if (XSTR (split, 3))
 600     printf ("%s\n", XSTR (split, 3));
 601
 602   /* Output code to copy the arguments back out of `operands'  */
 603   for (i = 0; i < operands; i++)
 604     printf ("  operand%d = operands[%d];\n", i, i);
 605
 606   /* Output code to construct the rtl for the instruction bodies.
 607      Use emit_insn to add them to the sequence being accumulated.
 608      But don't do this if the user's code has set `no_more' nonzero.  */
 609
 610   for (i = 0; i < XVECLEN (split, 2); i++)
 611     {
 612       rtx next = XVECEXP (split, 2, i);
 613       if ((GET_CODE (next) == SET && GET_CODE (SET_DEST (next)) == PC)
 614           || (GET_CODE (next) == PARALLEL
 615               && GET_CODE (XVECEXP (next, 0, 0)) == SET
 616               && GET_CODE (SET_DEST (XVECEXP (next, 0, 0))) == PC)
 617           || GET_CODE (next) == RETURN)
 618         printf ("  emit_jump_insn (");
 619       else if ((GET_CODE (next) == SET && GET_CODE (SET_SRC (next)) == CALL)
 620                || GET_CODE (next) == CALL
 621                || (GET_CODE (next) == PARALLEL
 622                    && GET_CODE (XVECEXP (next, 0, 0)) == SET
 623                    && GET_CODE (SET_SRC (XVECEXP (next, 0, 0))) == CALL)
 624                || (GET_CODE (next) == PARALLEL
 625                    && GET_CODE (XVECEXP (next, 0, 0)) == CALL))
 626         printf ("  emit_call_insn (");
 627       else if (GET_CODE (next) == CODE_LABEL)
 628         printf ("  emit_label (");
 629       else if (GET_CODE (next) == MATCH_OPERAND
 630                || GET_CODE (next) == MATCH_OPERATOR
 631                || GET_CODE (next) == MATCH_PARALLEL
 632                || GET_CODE (next) == MATCH_OP_DUP
 633                || GET_CODE (next) == MATCH_DUP
 634                || GET_CODE (next) == PARALLEL)
 635         printf ("  emit (");
 636       else
 637         printf ("  emit_insn (");
 638       gen_exp (next, GET_CODE (split));
 639       printf (");\n");
 640       if (GET_CODE (next) == SET && GET_CODE (SET_DEST (next)) == PC
 641           && GET_CODE (SET_SRC (next)) == LABEL_REF)
 642         printf ("  emit_barrier ();");
 643     }
 644
 645   /* Call `gen_sequence' to make a SEQUENCE out of all the
 646      insns emitted within this gen_... function.  */
 647
 648   printf ("  _val = gen_sequence ();\n");
 649   printf ("  end_sequence ();\n");
 650   printf ("  return _val;\n}\n\n");
 651 }
 652 \f
 653 /* Write a function, `add_clobbers', that is given a PARALLEL of sufficient
 654    size for the insn and an INSN_CODE, and inserts the required CLOBBERs at
 655    the end of the vector.  */
 656
 657 static void
 658 output_add_clobbers ()
 659 {
 660   struct clobber_pat *clobber;
 661   struct clobber_ent *ent;
 662   int i;
 663
 664   printf ("\n\nvoid\nadd_clobbers (pattern, insn_code_number)\n");
 665   printf ("     rtx pattern;\n     int insn_code_number;\n");
 666   printf ("{\n");
 667   printf ("  switch (insn_code_number)\n");
 668   printf ("    {\n");
 669
 670   for (clobber = clobber_list; clobber; clobber = clobber->next)
 671     {
 672       for (ent = clobber->insns; ent; ent = ent->next)
 673         printf ("    case %d:\n", ent->code_number);
 674
 675       for (i = clobber->first_clobber; i < XVECLEN (clobber->pattern, 1); i++)
 676         {
 677           printf ("      XVECEXP (pattern, 0, %d) = ", i);
 678           gen_exp (XVECEXP (clobber->pattern, 1, i),
 679                    GET_CODE (clobber->pattern));
 680           printf (";\n");
 681         }
 682
 683       printf ("      break;\n\n");
 684     }
 685
 686   printf ("    default:\n");
 687   printf ("      abort ();\n");
 688   printf ("    }\n");
 689   printf ("}\n");
 690 }
 691 \f
 692 /* Generate code to invoke find_free_register () as needed for the
 693    scratch registers used by the peephole2 pattern in SPLIT. */
 694
 695 static void
 696 output_peephole2_scratches (split)
 697      rtx split;
 698 {
 699   int i;
 700   int insn_nr = 0;
 701
 702   printf ("  HARD_REG_SET _regs_allocated;\n");
 703   printf ("  CLEAR_HARD_REG_SET (_regs_allocated);\n");
 704
 705   for (i = 0; i < XVECLEN (split, 0); i++)
 706     {
 707       rtx elt = XVECEXP (split, 0, i);
 708       if (GET_CODE (elt) == MATCH_SCRATCH)
 709         {
 710           int last_insn_nr = insn_nr;
 711           int cur_insn_nr = insn_nr;
 712           int j;
 713           for (j = i + 1; j < XVECLEN (split, 0); j++)
 714             if (GET_CODE (XVECEXP (split, 0, j)) == MATCH_DUP)
 715               {
 716                 if (XINT (XVECEXP (split, 0, j), 0) == XINT (elt, 0))
 717                   last_insn_nr = cur_insn_nr;
 718               }
 719             else if (GET_CODE (XVECEXP (split, 0, j)) != MATCH_SCRATCH)
 720               cur_insn_nr++;
 721
 722           printf ("  if ((operands[%d] = peep2_find_free_register (%d, %d, \"%s\", %smode, &_regs_allocated)) == NULL_RTX)\n\
 723     return NULL;\n",
 724                   XINT (elt, 0),
 725                   insn_nr, last_insn_nr,
 726                   XSTR (elt, 1),
 727                   GET_MODE_NAME (GET_MODE (elt)));
 728
 729         }
 730       else if (GET_CODE (elt) != MATCH_DUP)
 731         insn_nr++;
 732     }
 733 }
 734
 735 extern int main PARAMS ((int, char **));
 736
 737 int
 738 main (argc, argv)
 739      int argc;
 740      char **argv;
 741 {
 742   rtx desc;
 743
 744   progname = "genemit";
 745
 746   if (argc <= 1)
 747     fatal ("No input file name.");
 748
 749   if (init_md_reader (argv[1]) != SUCCESS_EXIT_CODE)
 750     return (FATAL_EXIT_CODE);
 751
 752   /* Assign sequential codes to all entries in the machine description
 753      in parallel with the tables in insn-output.c.  */
 754
 755   insn_code_number = 0;
 756   insn_index_number = 0;
 757
 758   printf ("/* Generated automatically by the program `genemit'\n\
 759 from the machine description file `md'.  */\n\n");
 760
 761   printf ("#include \"config.h\"\n");
 762   printf ("#include \"system.h\"\n");
 763   printf ("#include \"rtl.h\"\n");
 764   printf ("#include \"tm_p.h\"\n");
 765   printf ("#include \"function.h\"\n");
 766   printf ("#include \"expr.h\"\n");
 767   printf ("#include \"real.h\"\n");
 768   printf ("#include \"flags.h\"\n");
 769   printf ("#include \"output.h\"\n");
 770   printf ("#include \"insn-config.h\"\n");
 771   printf ("#include \"hard-reg-set.h\"\n");
 772   printf ("#include \"recog.h\"\n");
 773   printf ("#include \"resource.h\"\n");
 774   printf ("#include \"reload.h\"\n");
 775   printf ("#include \"ggc.h\"\n\n");
 776   printf ("#define FAIL return (end_sequence (), _val)\n");
 777   printf ("#define DONE return (_val = gen_sequence (), end_sequence (), _val)\n");
 778
 779   /* Read the machine description.  */
 780
 781   while (1)
 782     {
 783       int line_no;
 784
 785       desc = read_md_rtx (&line_no, &insn_code_number);
 786       if (desc == NULL)
 787         break;
 788
 789       switch (GET_CODE (desc))
 790         {
 791           case DEFINE_INSN:
 792               gen_insn (desc);
 793               break;
 794
 795           case DEFINE_EXPAND:
 796               gen_expand (desc);
 797               break;
 798
 799           case DEFINE_SPLIT:
 800               gen_split (desc);
 801               break;
 802
 803           case DEFINE_PEEPHOLE2:
 804               gen_split (desc);
 805               break;
 806
 807           default:
 808               break;
 809          }
 810       ++insn_index_number;
 811     }
 812
 813   /* Write out the routine to add CLOBBERs to a pattern.  */
 814   output_add_clobbers ();
 815
 816   fflush (stdout);
 817   return (ferror (stdout) != 0 ? FATAL_EXIT_CODE : SUCCESS_EXIT_CODE);
 818 }
 819
 820 /* Define this so we can link with print-rtl.o to get debug_rtx function.  */
 821 const char *
 822 get_insn_name (code)
 823      int code ATTRIBUTE_UNUSED;
 824 {
 825   return NULL;
 826 }