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, 2001,
   3    2003 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 "bconfig.h"
  24 #include "system.h"
  25 #include "coretypes.h"
  26 #include "tm.h"
  27 #include "rtl.h"
  28 #include "errors.h"
  29 #include "gensupport.h"
  30
  31
  32 static int max_opno;
  33 static int max_dup_opno;
  34 static int max_scratch_opno;
  35 static int register_constraints;
  36 static int insn_code_number;
  37 static int insn_index_number;
  38
  39 /* Data structure for recording the patterns of insns that have CLOBBERs.
  40    We use this to output a function that adds these CLOBBERs to a
  41    previously-allocated PARALLEL expression.  */
  42
  43 struct clobber_pat
  44 {
  45   struct clobber_ent *insns;
  46   rtx pattern;
  47   int first_clobber;
  48   struct clobber_pat *next;
  49   int has_hard_reg;
  50 } *clobber_list;
  51
  52 /* Records one insn that uses the clobber list.  */
  53
  54 struct clobber_ent
  55 {
  56   int code_number;              /* Counts only insns.  */
  57   struct clobber_ent *next;
  58 };
  59
  60 static void max_operand_1               (rtx);
  61 static int max_operand_vec              (rtx, int);
  62 static void print_code                  (RTX_CODE);
  63 static void gen_exp                     (rtx, enum rtx_code, char *);
  64 static void gen_insn                    (rtx, int);
  65 static void gen_expand                  (rtx);
  66 static void gen_split                   (rtx);
  67 static void output_add_clobbers         (void);
  68 static void output_added_clobbers_hard_reg_p (void);
  69 static void gen_rtx_scratch             (rtx, enum rtx_code);
  70 static void output_peephole2_scratches  (rtx);
  71
  72 \f
  73 static void
  74 max_operand_1 (rtx x)
  75 {
  76   RTX_CODE code;
  77   int i;
  78   int len;
  79   const char *fmt;
  80
  81   if (x == 0)
  82     return;
  83
  84   code = GET_CODE (x);
  85
  86   if (code == MATCH_OPERAND && XSTR (x, 2) != 0 && *XSTR (x, 2) != '\0')
  87     register_constraints = 1;
  88   if (code == MATCH_SCRATCH && XSTR (x, 1) != 0 && *XSTR (x, 1) != '\0')
  89     register_constraints = 1;
  90   if (code == MATCH_OPERAND || code == MATCH_OPERATOR
  91       || code == MATCH_PARALLEL)
  92     max_opno = MAX (max_opno, XINT (x, 0));
  93   if (code == MATCH_DUP || code == MATCH_OP_DUP || code == MATCH_PAR_DUP)
  94     max_dup_opno = MAX (max_dup_opno, XINT (x, 0));
  95   if (code == MATCH_SCRATCH)
  96     max_scratch_opno = MAX (max_scratch_opno, XINT (x, 0));
  97
  98   fmt = GET_RTX_FORMAT (code);
  99   len = GET_RTX_LENGTH (code);
 100   for (i = 0; i < len; i++)
 101     {
 102       if (fmt[i] == 'e' || fmt[i] == 'u')
 103         max_operand_1 (XEXP (x, i));
 104       else if (fmt[i] == 'E')
 105         {
 106           int j;
 107           for (j = 0; j < XVECLEN (x, i); j++)
 108             max_operand_1 (XVECEXP (x, i, j));
 109         }
 110     }
 111 }
 112
 113 static int
 114 max_operand_vec (rtx insn, int arg)
 115 {
 116   int len = XVECLEN (insn, arg);
 117   int i;
 118
 119   max_opno = -1;
 120   max_dup_opno = -1;
 121   max_scratch_opno = -1;
 122
 123   for (i = 0; i < len; i++)
 124     max_operand_1 (XVECEXP (insn, arg, i));
 125
 126   return max_opno + 1;
 127 }
 128 \f
 129 static void
 130 print_code (RTX_CODE code)
 131 {
 132   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 (rtx x, enum rtx_code subroutine_type)
 139 {
 140   if (subroutine_type == DEFINE_PEEPHOLE2)
 141     {
 142       printf ("operand%d", XINT (x, 0));
 143     }
 144   else
 145     {
 146       printf ("gen_rtx_SCRATCH (%smode)", GET_MODE_NAME (GET_MODE (x)));
 147     }
 148 }
 149
 150 /* Print a C expression to construct an RTX just like X,
 151    substituting any operand references appearing within.  */
 152
 153 static void
 154 gen_exp (rtx x, enum rtx_code subroutine_type, char *used)
 155 {
 156   RTX_CODE code;
 157   int i;
 158   int len;
 159   const char *fmt;
 160
 161   if (x == 0)
 162     {
 163       printf ("NULL_RTX");
 164       return;
 165     }
 166
 167   code = GET_CODE (x);
 168
 169   switch (code)
 170     {
 171     case MATCH_OPERAND:
 172     case MATCH_DUP:
 173       if (used)
 174         {
 175           if (used[XINT (x, 0)])
 176             {
 177               printf ("copy_rtx (operand%d)", XINT (x, 0));
 178               return;
 179             }
 180           used[XINT (x, 0)] = 1;
 181         }
 182       printf ("operand%d", XINT (x, 0));
 183       return;
 184
 185     case MATCH_OP_DUP:
 186       printf ("gen_rtx (GET_CODE (operand%d), ", XINT (x, 0));
 187       if (GET_MODE (x) == VOIDmode)
 188         printf ("GET_MODE (operand%d)", XINT (x, 0));
 189       else
 190         printf ("%smode", GET_MODE_NAME (GET_MODE (x)));
 191       for (i = 0; i < XVECLEN (x, 1); i++)
 192         {
 193           printf (",\n\t\t");
 194           gen_exp (XVECEXP (x, 1, i), subroutine_type, used);
 195         }
 196       printf (")");
 197       return;
 198
 199     case MATCH_OPERATOR:
 200       printf ("gen_rtx (GET_CODE (operand%d)", XINT (x, 0));
 201       printf (", %smode", GET_MODE_NAME (GET_MODE (x)));
 202       for (i = 0; i < XVECLEN (x, 2); i++)
 203         {
 204           printf (",\n\t\t");
 205           gen_exp (XVECEXP (x, 2, i), subroutine_type, used);
 206         }
 207       printf (")");
 208       return;
 209
 210     case MATCH_PARALLEL:
 211     case MATCH_PAR_DUP:
 212       printf ("operand%d", XINT (x, 0));
 213       return;
 214
 215     case MATCH_SCRATCH:
 216       gen_rtx_scratch (x, subroutine_type);
 217       return;
 218
 219     case ADDRESS:
 220       fatal ("ADDRESS expression code used in named instruction pattern");
 221
 222     case PC:
 223       printf ("pc_rtx");
 224       return;
 225
 226     case CC0:
 227       printf ("cc0_rtx");
 228       return;
 229
 230     case CONST_INT:
 231       if (INTVAL (x) == 0)
 232         printf ("const0_rtx");
 233       else if (INTVAL (x) == 1)
 234         printf ("const1_rtx");
 235       else if (INTVAL (x) == -1)
 236         printf ("constm1_rtx");
 237       else if (INTVAL (x) == STORE_FLAG_VALUE)
 238         printf ("const_true_rtx");
 239       else
 240         {
 241           printf ("GEN_INT (");
 242           printf (HOST_WIDE_INT_PRINT_DEC_C, INTVAL (x));
 243           printf (")");
 244         }
 245       return;
 246
 247     case CONST_DOUBLE:
 248       /* These shouldn't be written in MD files.  Instead, the appropriate
 249          routines in varasm.c should be called.  */
 250       abort ();
 251
 252     default:
 253       break;
 254     }
 255
 256   printf ("gen_rtx_");
 257   print_code (code);
 258   printf (" (%smode", GET_MODE_NAME (GET_MODE (x)));
 259
 260   fmt = GET_RTX_FORMAT (code);
 261   len = GET_RTX_LENGTH (code);
 262   for (i = 0; i < len; i++)
 263     {
 264       if (fmt[i] == '0')
 265         break;
 266       printf (",\n\t");
 267       if (fmt[i] == 'e' || fmt[i] == 'u')
 268         gen_exp (XEXP (x, i), subroutine_type, used);
 269       else if (fmt[i] == 'i')
 270         printf ("%u", XINT (x, i));
 271       else if (fmt[i] == 's')
 272         printf ("\"%s\"", XSTR (x, i));
 273       else if (fmt[i] == 'E')
 274         {
 275           int j;
 276           printf ("gen_rtvec (%d", XVECLEN (x, i));
 277           for (j = 0; j < XVECLEN (x, i); j++)
 278             {
 279               printf (",\n\t\t");
 280               gen_exp (XVECEXP (x, i, j), subroutine_type, used);
 281             }
 282           printf (")");
 283         }
 284       else
 285         abort ();
 286     }
 287   printf (")");
 288 }
 289 \f
 290 /* Generate the `gen_...' function for a DEFINE_INSN.  */
 291
 292 static void
 293 gen_insn (rtx insn, int lineno)
 294 {
 295   int operands;
 296   int i;
 297
 298   /* See if the pattern for this insn ends with a group of CLOBBERs of (hard)
 299      registers or MATCH_SCRATCHes.  If so, store away the information for
 300      later.  */
 301
 302   if (XVEC (insn, 1))
 303     {
 304       int has_hard_reg = 0;
 305
 306       for (i = XVECLEN (insn, 1) - 1; i > 0; i--)
 307         {
 308           if (GET_CODE (XVECEXP (insn, 1, i)) != CLOBBER)
 309             break;
 310
 311           if (GET_CODE (XEXP (XVECEXP (insn, 1, i), 0)) == REG)
 312             has_hard_reg = 1;
 313           else if (GET_CODE (XEXP (XVECEXP (insn, 1, i), 0)) != MATCH_SCRATCH)
 314             break;
 315         }
 316
 317       if (i != XVECLEN (insn, 1) - 1)
 318         {
 319           struct clobber_pat *p;
 320           struct clobber_ent *link = xmalloc (sizeof (struct clobber_ent));
 321           int j;
 322
 323           link->code_number = insn_code_number;
 324
 325           /* See if any previous CLOBBER_LIST entry is the same as this
 326              one.  */
 327
 328           for (p = clobber_list; p; p = p->next)
 329             {
 330               if (p->first_clobber != i + 1
 331                   || XVECLEN (p->pattern, 1) != XVECLEN (insn, 1))
 332                 continue;
 333
 334               for (j = i + 1; j < XVECLEN (insn, 1); j++)
 335                 {
 336                   rtx old = XEXP (XVECEXP (p->pattern, 1, j), 0);
 337                   rtx new = XEXP (XVECEXP (insn, 1, j), 0);
 338
 339                   /* OLD and NEW are the same if both are to be a SCRATCH
 340                      of the same mode,
 341                      or if both are registers of the same mode and number.  */
 342                   if (! (GET_MODE (old) == GET_MODE (new)
 343                          && ((GET_CODE (old) == MATCH_SCRATCH
 344                               && GET_CODE (new) == MATCH_SCRATCH)
 345                              || (GET_CODE (old) == REG && GET_CODE (new) == REG
 346                                  && REGNO (old) == REGNO (new)))))
 347                     break;
 348                 }
 349
 350               if (j == XVECLEN (insn, 1))
 351                 break;
 352             }
 353
 354           if (p == 0)
 355             {
 356               p = xmalloc (sizeof (struct clobber_pat));
 357
 358               p->insns = 0;
 359               p->pattern = insn;
 360               p->first_clobber = i + 1;
 361               p->next = clobber_list;
 362               p->has_hard_reg = has_hard_reg;
 363               clobber_list = p;
 364             }
 365
 366           link->next = p->insns;
 367           p->insns = link;
 368         }
 369     }
 370
 371   /* Don't mention instructions whose names are the null string
 372      or begin with '*'.  They are in the machine description just
 373      to be recognized.  */
 374   if (XSTR (insn, 0)[0] == 0 || XSTR (insn, 0)[0] == '*')
 375     return;
 376
 377   printf ("/* %s:%d */\n", read_rtx_filename, lineno);
 378
 379   /* Find out how many operands this function has,
 380      and also whether any of them have register constraints.  */
 381   register_constraints = 0;
 382   operands = max_operand_vec (insn, 1);
 383   if (max_dup_opno >= operands)
 384     fatal ("match_dup operand number has no match_operand");
 385
 386   /* Output the function name and argument declarations.  */
 387   printf ("rtx\ngen_%s (", XSTR (insn, 0));
 388   if (operands)
 389     for (i = 0; i < operands; i++)
 390       if (i)
 391         printf (",\n\trtx operand%d ATTRIBUTE_UNUSED", i);
 392       else
 393         printf ("rtx operand%d ATTRIBUTE_UNUSED", i);
 394   else
 395     printf ("void");
 396   printf (")\n");
 397   printf ("{\n");
 398
 399   /* Output code to construct and return the rtl for the instruction body */
 400
 401   if (XVECLEN (insn, 1) == 1)
 402     {
 403       printf ("  return ");
 404       gen_exp (XVECEXP (insn, 1, 0), DEFINE_INSN, NULL);
 405       printf (";\n}\n\n");
 406     }
 407   else
 408     {
 409       printf ("  return gen_rtx_PARALLEL (VOIDmode, gen_rtvec (%d",
 410               XVECLEN (insn, 1));
 411
 412       for (i = 0; i < XVECLEN (insn, 1); i++)
 413         {
 414           printf (",\n\t\t");
 415           gen_exp (XVECEXP (insn, 1, i), DEFINE_INSN, NULL);
 416         }
 417       printf ("));\n}\n\n");
 418     }
 419 }
 420 \f
 421 /* Generate the `gen_...' function for a DEFINE_EXPAND.  */
 422
 423 static void
 424 gen_expand (rtx expand)
 425 {
 426   int operands;
 427   int i;
 428
 429   if (strlen (XSTR (expand, 0)) == 0)
 430     fatal ("define_expand lacks a name");
 431   if (XVEC (expand, 1) == 0)
 432     fatal ("define_expand for %s lacks a pattern", XSTR (expand, 0));
 433
 434   /* Find out how many operands this function has,
 435      and also whether any of them have register constraints.  */
 436   register_constraints = 0;
 437
 438   operands = max_operand_vec (expand, 1);
 439
 440   /* Output the function name and argument declarations.  */
 441   printf ("rtx\ngen_%s (", XSTR (expand, 0));
 442   if (operands)
 443     for (i = 0; i < operands; i++)
 444       if (i)
 445         printf (",\n\trtx operand%d", i);
 446       else
 447         printf ("rtx operand%d", i);
 448   else
 449     printf ("void");
 450   printf (")\n");
 451   printf ("{\n");
 452
 453   /* If we don't have any C code to write, only one insn is being written,
 454      and no MATCH_DUPs are present, we can just return the desired insn
 455      like we do for a DEFINE_INSN.  This saves memory.  */
 456   if ((XSTR (expand, 3) == 0 || *XSTR (expand, 3) == '\0')
 457       && operands > max_dup_opno
 458       && XVECLEN (expand, 1) == 1)
 459     {
 460       printf ("  return ");
 461       gen_exp (XVECEXP (expand, 1, 0), DEFINE_EXPAND, NULL);
 462       printf (";\n}\n\n");
 463       return;
 464     }
 465
 466   /* For each operand referred to only with MATCH_DUPs,
 467      make a local variable.  */
 468   for (i = operands; i <= max_dup_opno; i++)
 469     printf ("  rtx operand%d;\n", i);
 470   for (; i <= max_scratch_opno; i++)
 471     printf ("  rtx operand%d ATTRIBUTE_UNUSED;\n", i);
 472   printf ("  rtx _val = 0;\n");
 473   printf ("  start_sequence ();\n");
 474
 475   /* The fourth operand of DEFINE_EXPAND is some code to be executed
 476      before the actual construction.
 477      This code expects to refer to `operands'
 478      just as the output-code in a DEFINE_INSN does,
 479      but here `operands' is an automatic array.
 480      So copy the operand values there before executing it.  */
 481   if (XSTR (expand, 3) && *XSTR (expand, 3))
 482     {
 483       printf ("  {\n");
 484       if (operands > 0 || max_dup_opno >= 0 || max_scratch_opno >= 0)
 485         printf ("    rtx operands[%d];\n",
 486             MAX (operands, MAX (max_scratch_opno, max_dup_opno) + 1));
 487       /* Output code to copy the arguments into `operands'.  */
 488       for (i = 0; i < operands; i++)
 489         printf ("    operands[%d] = operand%d;\n", i, i);
 490
 491       /* Output the special code to be executed before the sequence
 492          is generated.  */
 493       printf ("%s\n", XSTR (expand, 3));
 494
 495       /* Output code to copy the arguments back out of `operands'
 496          (unless we aren't going to use them at all).  */
 497       if (XVEC (expand, 1) != 0)
 498         {
 499           for (i = 0; i < operands; i++)
 500             printf ("    operand%d = operands[%d];\n", i, i);
 501           for (; i <= max_dup_opno; i++)
 502             printf ("    operand%d = operands[%d];\n", i, i);
 503           for (; i <= max_scratch_opno; i++)
 504             printf ("    operand%d = operands[%d];\n", i, i);
 505         }
 506       printf ("  }\n");
 507     }
 508
 509   /* Output code to construct the rtl for the instruction bodies.
 510      Use emit_insn to add them to the sequence being accumulated.
 511      But don't do this if the user's code has set `no_more' nonzero.  */
 512
 513   for (i = 0; i < XVECLEN (expand, 1); i++)
 514     {
 515       rtx next = XVECEXP (expand, 1, i);
 516       if ((GET_CODE (next) == SET && GET_CODE (SET_DEST (next)) == PC)
 517           || (GET_CODE (next) == PARALLEL
 518               && ((GET_CODE (XVECEXP (next, 0, 0)) == SET
 519                    && GET_CODE (SET_DEST (XVECEXP (next, 0, 0))) == PC)
 520                   || GET_CODE (XVECEXP (next, 0, 0)) == RETURN))
 521           || GET_CODE (next) == RETURN)
 522         printf ("  emit_jump_insn (");
 523       else if ((GET_CODE (next) == SET && GET_CODE (SET_SRC (next)) == CALL)
 524                || GET_CODE (next) == CALL
 525                || (GET_CODE (next) == PARALLEL
 526                    && GET_CODE (XVECEXP (next, 0, 0)) == SET
 527                    && GET_CODE (SET_SRC (XVECEXP (next, 0, 0))) == CALL)
 528                || (GET_CODE (next) == PARALLEL
 529                    && GET_CODE (XVECEXP (next, 0, 0)) == CALL))
 530         printf ("  emit_call_insn (");
 531       else if (GET_CODE (next) == CODE_LABEL)
 532         printf ("  emit_label (");
 533       else if (GET_CODE (next) == MATCH_OPERAND
 534                || GET_CODE (next) == MATCH_DUP
 535                || GET_CODE (next) == MATCH_OPERATOR
 536                || GET_CODE (next) == MATCH_OP_DUP
 537                || GET_CODE (next) == MATCH_PARALLEL
 538                || GET_CODE (next) == MATCH_PAR_DUP
 539                || GET_CODE (next) == PARALLEL)
 540         printf ("  emit (");
 541       else
 542         printf ("  emit_insn (");
 543       gen_exp (next, DEFINE_EXPAND, NULL);
 544       printf (");\n");
 545       if (GET_CODE (next) == SET && GET_CODE (SET_DEST (next)) == PC
 546           && GET_CODE (SET_SRC (next)) == LABEL_REF)
 547         printf ("  emit_barrier ();");
 548     }
 549
 550   /* Call `get_insns' to extract the list of all the
 551      insns emitted within this gen_... function.  */
 552
 553   printf ("  _val = get_insns ();\n");
 554   printf ("  end_sequence ();\n");
 555   printf ("  return _val;\n}\n\n");
 556 }
 557
 558 /* Like gen_expand, but generates insns resulting from splitting SPLIT.  */
 559
 560 static void
 561 gen_split (rtx split)
 562 {
 563   int i;
 564   int operands;
 565   const char *const name =
 566     ((GET_CODE (split) == DEFINE_PEEPHOLE2) ? "peephole2" : "split");
 567   const char *unused;
 568   char *used;
 569
 570   if (XVEC (split, 0) == 0)
 571     fatal ("define_%s (definition %d) lacks a pattern", name,
 572            insn_index_number);
 573   else if (XVEC (split, 2) == 0)
 574     fatal ("define_%s (definition %d) lacks a replacement pattern", name,
 575            insn_index_number);
 576
 577   /* Find out how many operands this function has.  */
 578
 579   max_operand_vec (split, 2);
 580   operands = MAX (max_opno, MAX (max_dup_opno, max_scratch_opno)) + 1;
 581   unused = (operands == 0 ? " ATTRIBUTE_UNUSED" : "");
 582   used = xcalloc (1, operands);
 583
 584   /* Output the prototype, function name and argument declarations.  */
 585   if (GET_CODE (split) == DEFINE_PEEPHOLE2)
 586     {
 587       printf ("extern rtx gen_%s_%d (rtx, rtx *);\n",
 588               name, insn_code_number);
 589       printf ("rtx\ngen_%s_%d (rtx curr_insn ATTRIBUTE_UNUSED, rtx *operands%s)\n",
 590               name, insn_code_number, unused);
 591     }
 592   else
 593     {
 594       printf ("extern rtx gen_split_%d (rtx *);\n", insn_code_number);
 595       printf ("rtx\ngen_%s_%d (rtx *operands%s)\n", name, insn_code_number, unused);
 596     }
 597   printf ("{\n");
 598
 599   /* Declare all local variables.  */
 600   for (i = 0; i < operands; i++)
 601     printf ("  rtx operand%d;\n", i);
 602   printf ("  rtx _val = 0;\n");
 603
 604   if (GET_CODE (split) == DEFINE_PEEPHOLE2)
 605     output_peephole2_scratches (split);
 606
 607   printf ("  start_sequence ();\n");
 608
 609   /* The fourth operand of DEFINE_SPLIT is some code to be executed
 610      before the actual construction.  */
 611
 612   if (XSTR (split, 3))
 613     printf ("%s\n", XSTR (split, 3));
 614
 615   /* Output code to copy the arguments back out of `operands'  */
 616   for (i = 0; i < operands; i++)
 617     printf ("  operand%d = operands[%d];\n", i, i);
 618
 619   /* Output code to construct the rtl for the instruction bodies.
 620      Use emit_insn to add them to the sequence being accumulated.
 621      But don't do this if the user's code has set `no_more' nonzero.  */
 622
 623   for (i = 0; i < XVECLEN (split, 2); i++)
 624     {
 625       rtx next = XVECEXP (split, 2, i);
 626       if ((GET_CODE (next) == SET && GET_CODE (SET_DEST (next)) == PC)
 627           || (GET_CODE (next) == PARALLEL
 628               && GET_CODE (XVECEXP (next, 0, 0)) == SET
 629               && GET_CODE (SET_DEST (XVECEXP (next, 0, 0))) == PC)
 630           || GET_CODE (next) == RETURN)
 631         printf ("  emit_jump_insn (");
 632       else if ((GET_CODE (next) == SET && GET_CODE (SET_SRC (next)) == CALL)
 633                || GET_CODE (next) == CALL
 634                || (GET_CODE (next) == PARALLEL
 635                    && GET_CODE (XVECEXP (next, 0, 0)) == SET
 636                    && GET_CODE (SET_SRC (XVECEXP (next, 0, 0))) == CALL)
 637                || (GET_CODE (next) == PARALLEL
 638                    && GET_CODE (XVECEXP (next, 0, 0)) == CALL))
 639         printf ("  emit_call_insn (");
 640       else if (GET_CODE (next) == CODE_LABEL)
 641         printf ("  emit_label (");
 642       else if (GET_CODE (next) == MATCH_OPERAND
 643                || GET_CODE (next) == MATCH_OPERATOR
 644                || GET_CODE (next) == MATCH_PARALLEL
 645                || GET_CODE (next) == MATCH_OP_DUP
 646                || GET_CODE (next) == MATCH_DUP
 647                || GET_CODE (next) == PARALLEL)
 648         printf ("  emit (");
 649       else
 650         printf ("  emit_insn (");
 651       gen_exp (next, GET_CODE (split), used);
 652       printf (");\n");
 653       if (GET_CODE (next) == SET && GET_CODE (SET_DEST (next)) == PC
 654           && GET_CODE (SET_SRC (next)) == LABEL_REF)
 655         printf ("  emit_barrier ();");
 656     }
 657
 658   /* Call `get_insns' to make a list of all the
 659      insns emitted within this gen_... function.  */
 660
 661   printf ("  _val = get_insns ();\n");
 662   printf ("  end_sequence ();\n");
 663   printf ("  return _val;\n}\n\n");
 664
 665   free (used);
 666 }
 667 \f
 668 /* Write a function, `add_clobbers', that is given a PARALLEL of sufficient
 669    size for the insn and an INSN_CODE, and inserts the required CLOBBERs at
 670    the end of the vector.  */
 671
 672 static void
 673 output_add_clobbers (void)
 674 {
 675   struct clobber_pat *clobber;
 676   struct clobber_ent *ent;
 677   int i;
 678
 679   printf ("\n\nvoid\nadd_clobbers (rtx pattern ATTRIBUTE_UNUSED, int insn_code_number)\n");
 680   printf ("{\n");
 681   printf ("  switch (insn_code_number)\n");
 682   printf ("    {\n");
 683
 684   for (clobber = clobber_list; clobber; clobber = clobber->next)
 685     {
 686       for (ent = clobber->insns; ent; ent = ent->next)
 687         printf ("    case %d:\n", ent->code_number);
 688
 689       for (i = clobber->first_clobber; i < XVECLEN (clobber->pattern, 1); i++)
 690         {
 691           printf ("      XVECEXP (pattern, 0, %d) = ", i);
 692           gen_exp (XVECEXP (clobber->pattern, 1, i),
 693                    GET_CODE (clobber->pattern), NULL);
 694           printf (";\n");
 695         }
 696
 697       printf ("      break;\n\n");
 698     }
 699
 700   printf ("    default:\n");
 701   printf ("      abort ();\n");
 702   printf ("    }\n");
 703   printf ("}\n");
 704 }
 705 \f
 706 /* Write a function, `added_clobbers_hard_reg_p' this is given an insn_code
 707    number that needs clobbers and returns 1 if they include a clobber of a
 708    hard reg and 0 if they just clobber SCRATCH.  */
 709
 710 static void
 711 output_added_clobbers_hard_reg_p (void)
 712 {
 713   struct clobber_pat *clobber;
 714   struct clobber_ent *ent;
 715   int clobber_p, used;
 716
 717   printf ("\n\nint\nadded_clobbers_hard_reg_p (int insn_code_number)\n");
 718   printf ("{\n");
 719   printf ("  switch (insn_code_number)\n");
 720   printf ("    {\n");
 721
 722   for (clobber_p = 0; clobber_p <= 1; clobber_p++)
 723     {
 724       used = 0;
 725       for (clobber = clobber_list; clobber; clobber = clobber->next)
 726         if (clobber->has_hard_reg == clobber_p)
 727           for (ent = clobber->insns; ent; ent = ent->next)
 728             {
 729               printf ("    case %d:\n", ent->code_number);
 730               used++;
 731             }
 732
 733       if (used)
 734         printf ("      return %d;\n\n", clobber_p);
 735     }
 736
 737   printf ("    default:\n");
 738   printf ("      abort ();\n");
 739   printf ("    }\n");
 740   printf ("}\n");
 741 }
 742 \f
 743 /* Generate code to invoke find_free_register () as needed for the
 744    scratch registers used by the peephole2 pattern in SPLIT.  */
 745
 746 static void
 747 output_peephole2_scratches (rtx split)
 748 {
 749   int i;
 750   int insn_nr = 0;
 751
 752   printf ("  HARD_REG_SET _regs_allocated;\n");
 753   printf ("  CLEAR_HARD_REG_SET (_regs_allocated);\n");
 754
 755   for (i = 0; i < XVECLEN (split, 0); i++)
 756     {
 757       rtx elt = XVECEXP (split, 0, i);
 758       if (GET_CODE (elt) == MATCH_SCRATCH)
 759         {
 760           int last_insn_nr = insn_nr;
 761           int cur_insn_nr = insn_nr;
 762           int j;
 763           for (j = i + 1; j < XVECLEN (split, 0); j++)
 764             if (GET_CODE (XVECEXP (split, 0, j)) == MATCH_DUP)
 765               {
 766                 if (XINT (XVECEXP (split, 0, j), 0) == XINT (elt, 0))
 767                   last_insn_nr = cur_insn_nr;
 768               }
 769             else if (GET_CODE (XVECEXP (split, 0, j)) != MATCH_SCRATCH)
 770               cur_insn_nr++;
 771
 772           printf ("  if ((operands[%d] = peep2_find_free_register (%d, %d, \"%s\", %smode, &_regs_allocated)) == NULL_RTX)\n\
 773     return NULL;\n",
 774                   XINT (elt, 0),
 775                   insn_nr, last_insn_nr,
 776                   XSTR (elt, 1),
 777                   GET_MODE_NAME (GET_MODE (elt)));
 778
 779         }
 780       else if (GET_CODE (elt) != MATCH_DUP)
 781         insn_nr++;
 782     }
 783 }
 784
 785 int
 786 main (int argc, char **argv)
 787 {
 788   rtx desc;
 789
 790   progname = "genemit";
 791
 792   if (argc <= 1)
 793     fatal ("no input file name");
 794
 795   if (init_md_reader_args (argc, argv) != SUCCESS_EXIT_CODE)
 796     return (FATAL_EXIT_CODE);
 797
 798   /* Assign sequential codes to all entries in the machine description
 799      in parallel with the tables in insn-output.c.  */
 800
 801   insn_code_number = 0;
 802   insn_index_number = 0;
 803
 804   printf ("/* Generated automatically by the program `genemit'\n\
 805 from the machine description file `md'.  */\n\n");
 806
 807   printf ("#include \"config.h\"\n");
 808   printf ("#include \"system.h\"\n");
 809   printf ("#include \"coretypes.h\"\n");
 810   printf ("#include \"tm.h\"\n");
 811   printf ("#include \"rtl.h\"\n");
 812   printf ("#include \"tm_p.h\"\n");
 813   printf ("#include \"function.h\"\n");
 814   printf ("#include \"expr.h\"\n");
 815   printf ("#include \"optabs.h\"\n");
 816   printf ("#include \"real.h\"\n");
 817   printf ("#include \"flags.h\"\n");
 818   printf ("#include \"output.h\"\n");
 819   printf ("#include \"insn-config.h\"\n");
 820   printf ("#include \"hard-reg-set.h\"\n");
 821   printf ("#include \"recog.h\"\n");
 822   printf ("#include \"resource.h\"\n");
 823   printf ("#include \"reload.h\"\n");
 824   printf ("#include \"toplev.h\"\n");
 825   printf ("#include \"ggc.h\"\n\n");
 826   printf ("#define FAIL return (end_sequence (), _val)\n");
 827   printf ("#define DONE return (_val = get_insns (), end_sequence (), _val)\n\n");
 828
 829   /* Read the machine description.  */
 830
 831   while (1)
 832     {
 833       int line_no;
 834
 835       desc = read_md_rtx (&line_no, &insn_code_number);
 836       if (desc == NULL)
 837         break;
 838
 839       switch (GET_CODE (desc))
 840         {
 841         case DEFINE_INSN:
 842           gen_insn (desc, line_no);
 843           break;
 844
 845         case DEFINE_EXPAND:
 846           printf ("/* %s:%d */\n", read_rtx_filename, line_no);
 847           gen_expand (desc);
 848           break;
 849
 850         case DEFINE_SPLIT:
 851           printf ("/* %s:%d */\n", read_rtx_filename, line_no);
 852           gen_split (desc);
 853           break;
 854
 855         case DEFINE_PEEPHOLE2:
 856           printf ("/* %s:%d */\n", read_rtx_filename, line_no);
 857           gen_split (desc);
 858           break;
 859
 860         default:
 861           break;
 862         }
 863       ++insn_index_number;
 864     }
 865
 866   /* Write out the routines to add CLOBBERs to a pattern and say whether they
 867      clobber a hard reg.  */
 868   output_add_clobbers ();
 869   output_added_clobbers_hard_reg_p ();
 870
 871   fflush (stdout);
 872   return (ferror (stdout) != 0 ? FATAL_EXIT_CODE : SUCCESS_EXIT_CODE);
 873 }
 874
 875 /* Define this so we can link with print-rtl.o to get debug_rtx function.  */
 876 const char *
 877 get_insn_name (int code ATTRIBUTE_UNUSED)
 878 {
 879   return NULL;
 880 }