gcc/genemit.c

   1 /* Generate code from machine description to emit insns as rtl.
   2    Copyright (C) 1987-2015 Free Software Foundation, Inc.
   3
   4 This file is part of GCC.
   5
   6 GCC is free software; you can redistribute it and/or modify it under
   7 the terms of the GNU General Public License as published by the Free
   8 Software Foundation; either version 3, or (at your option) any later
   9 version.
  10
  11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14 for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GCC; see the file COPYING3.  If not see
  18 <http://www.gnu.org/licenses/>.  */
  19
  20
  21 #include "bconfig.h"
  22 #include "system.h"
  23 #include "coretypes.h"
  24 #include "tm.h"
  25 #include "rtl.h"
  26 #include "errors.h"
  27 #include "read-md.h"
  28 #include "gensupport.h"
  29
  30
  31 static int insn_code_number;
  32 static int insn_index_number;
  33
  34 /* Data structure for recording the patterns of insns that have CLOBBERs.
  35    We use this to output a function that adds these CLOBBERs to a
  36    previously-allocated PARALLEL expression.  */
  37
  38 struct clobber_pat
  39 {
  40   struct clobber_ent *insns;
  41   rtx pattern;
  42   int first_clobber;
  43   struct clobber_pat *next;
  44   int has_hard_reg;
  45 } *clobber_list;
  46
  47 /* Records one insn that uses the clobber list.  */
  48
  49 struct clobber_ent
  50 {
  51   int code_number;              /* Counts only insns.  */
  52   struct clobber_ent *next;
  53 };
  54
  55 static void print_code                  (RTX_CODE);
  56 static void gen_exp                     (rtx, enum rtx_code, char *);
  57 static void gen_insn                    (rtx, int);
  58 static void gen_expand                  (rtx);
  59 static void gen_split                   (rtx);
  60 static void output_add_clobbers         (void);
  61 static void output_added_clobbers_hard_reg_p (void);
  62 static void gen_rtx_scratch             (rtx, enum rtx_code);
  63 static void output_peephole2_scratches  (rtx);
  64
  65 \f
  66 static void
  67 print_code (RTX_CODE code)
  68 {
  69   const char *p1;
  70   for (p1 = GET_RTX_NAME (code); *p1; p1++)
  71     putchar (TOUPPER (*p1));
  72 }
  73
  74 static void
  75 gen_rtx_scratch (rtx x, enum rtx_code subroutine_type)
  76 {
  77   if (subroutine_type == DEFINE_PEEPHOLE2)
  78     {
  79       printf ("operand%d", XINT (x, 0));
  80     }
  81   else
  82     {
  83       printf ("gen_rtx_SCRATCH (%smode)", GET_MODE_NAME (GET_MODE (x)));
  84     }
  85 }
  86
  87 /* Print a C expression to construct an RTX just like X,
  88    substituting any operand references appearing within.  */
  89
  90 static void
  91 gen_exp (rtx x, enum rtx_code subroutine_type, char *used)
  92 {
  93   RTX_CODE code;
  94   int i;
  95   int len;
  96   const char *fmt;
  97   const char *sep = "";
  98
  99   if (x == 0)
 100     {
 101       printf ("NULL_RTX");
 102       return;
 103     }
 104
 105   code = GET_CODE (x);
 106
 107   switch (code)
 108     {
 109     case MATCH_OPERAND:
 110     case MATCH_DUP:
 111       if (used)
 112         {
 113           if (used[XINT (x, 0)])
 114             {
 115               printf ("copy_rtx (operand%d)", XINT (x, 0));
 116               return;
 117             }
 118           used[XINT (x, 0)] = 1;
 119         }
 120       printf ("operand%d", XINT (x, 0));
 121       return;
 122
 123     case MATCH_OP_DUP:
 124       printf ("gen_rtx_fmt_");
 125       for (i = 0; i < XVECLEN (x, 1); i++)
 126         printf ("e");
 127       printf (" (GET_CODE (operand%d), ", XINT (x, 0));
 128       if (GET_MODE (x) == VOIDmode)
 129         printf ("GET_MODE (operand%d)", XINT (x, 0));
 130       else
 131         printf ("%smode", GET_MODE_NAME (GET_MODE (x)));
 132       for (i = 0; i < XVECLEN (x, 1); i++)
 133         {
 134           printf (",\n\t\t");
 135           gen_exp (XVECEXP (x, 1, i), subroutine_type, used);
 136         }
 137       printf (")");
 138       return;
 139
 140     case MATCH_OPERATOR:
 141       printf ("gen_rtx_fmt_");
 142       for (i = 0; i < XVECLEN (x, 2); i++)
 143         printf ("e");
 144       printf (" (GET_CODE (operand%d)", XINT (x, 0));
 145       printf (", %smode", GET_MODE_NAME (GET_MODE (x)));
 146       for (i = 0; i < XVECLEN (x, 2); i++)
 147         {
 148           printf (",\n\t\t");
 149           gen_exp (XVECEXP (x, 2, i), subroutine_type, used);
 150         }
 151       printf (")");
 152       return;
 153
 154     case MATCH_PARALLEL:
 155     case MATCH_PAR_DUP:
 156       printf ("operand%d", XINT (x, 0));
 157       return;
 158
 159     case MATCH_SCRATCH:
 160       gen_rtx_scratch (x, subroutine_type);
 161       return;
 162
 163     case PC:
 164       printf ("pc_rtx");
 165       return;
 166     case RETURN:
 167       printf ("ret_rtx");
 168       return;
 169     case SIMPLE_RETURN:
 170       printf ("simple_return_rtx");
 171       return;
 172     case CLOBBER:
 173       if (REG_P (XEXP (x, 0)))
 174         {
 175           printf ("gen_hard_reg_clobber (%smode, %i)", GET_MODE_NAME (GET_MODE (XEXP (x, 0))),
 176                                                      REGNO (XEXP (x, 0)));
 177           return;
 178         }
 179       break;
 180
 181     case CC0:
 182       printf ("cc0_rtx");
 183       return;
 184
 185     case CONST_INT:
 186       if (INTVAL (x) == 0)
 187         printf ("const0_rtx");
 188       else if (INTVAL (x) == 1)
 189         printf ("const1_rtx");
 190       else if (INTVAL (x) == -1)
 191         printf ("constm1_rtx");
 192       else if (-MAX_SAVED_CONST_INT <= INTVAL (x)
 193           && INTVAL (x) <= MAX_SAVED_CONST_INT)
 194         printf ("const_int_rtx[MAX_SAVED_CONST_INT + (%d)]",
 195                 (int) INTVAL (x));
 196       else if (INTVAL (x) == STORE_FLAG_VALUE)
 197         printf ("const_true_rtx");
 198       else
 199         {
 200           printf ("GEN_INT (");
 201           printf (HOST_WIDE_INT_PRINT_DEC_C, INTVAL (x));
 202           printf (")");
 203         }
 204       return;
 205
 206     case CONST_DOUBLE:
 207     case CONST_FIXED:
 208     case CONST_WIDE_INT:
 209       /* These shouldn't be written in MD files.  Instead, the appropriate
 210          routines in varasm.c should be called.  */
 211       gcc_unreachable ();
 212
 213     default:
 214       break;
 215     }
 216
 217   printf ("gen_rtx_");
 218   print_code (code);
 219   printf (" (");
 220   if (!always_void_p (code))
 221     {
 222       printf ("%smode", GET_MODE_NAME (GET_MODE (x)));
 223       sep = ",\n\t";
 224     }
 225
 226   fmt = GET_RTX_FORMAT (code);
 227   len = GET_RTX_LENGTH (code);
 228   for (i = 0; i < len; i++)
 229     {
 230       if (fmt[i] == '0')
 231         break;
 232       fputs (sep, stdout);
 233       switch (fmt[i])
 234         {
 235         case 'e': case 'u':
 236           gen_exp (XEXP (x, i), subroutine_type, used);
 237           break;
 238
 239         case 'i':
 240           printf ("%u", XINT (x, i));
 241           break;
 242
 243         case 'r':
 244           printf ("%u", REGNO (x));
 245           break;
 246
 247         case 's':
 248           printf ("\"%s\"", XSTR (x, i));
 249           break;
 250
 251         case 'E':
 252           {
 253             int j;
 254             printf ("gen_rtvec (%d", XVECLEN (x, i));
 255             for (j = 0; j < XVECLEN (x, i); j++)
 256               {
 257                 printf (",\n\t\t");
 258                 gen_exp (XVECEXP (x, i, j), subroutine_type, used);
 259               }
 260             printf (")");
 261             break;
 262           }
 263
 264         default:
 265           gcc_unreachable ();
 266         }
 267       sep = ",\n\t";
 268     }
 269   printf (")");
 270 }
 271
 272 /* Output code to emit the instruction patterns in VEC, with each element
 273    becoming a separate instruction.  USED is as for gen_exp.  */
 274
 275 static void
 276 gen_emit_seq (rtvec vec, char *used)
 277 {
 278   for (int i = 0, len = GET_NUM_ELEM (vec); i < len; ++i)
 279     {
 280       bool last_p = (i == len - 1);
 281       rtx next = RTVEC_ELT (vec, i);
 282       if (const char *name = get_emit_function (next))
 283         {
 284           printf ("  %s (", name);
 285           gen_exp (next, DEFINE_EXPAND, used);
 286           printf (");\n");
 287           if (!last_p && needs_barrier_p (next))
 288             printf ("  emit_barrier ();");
 289         }
 290       else
 291         {
 292           printf ("  emit (");
 293           gen_exp (next, DEFINE_EXPAND, used);
 294           printf (", %s);\n", last_p ? "false" : "true");
 295         }
 296     }
 297 }
 298 \f
 299 /* Generate the `gen_...' function for a DEFINE_INSN.  */
 300
 301 static void
 302 gen_insn (rtx insn, int lineno)
 303 {
 304   struct pattern_stats stats;
 305   int i;
 306
 307   /* See if the pattern for this insn ends with a group of CLOBBERs of (hard)
 308      registers or MATCH_SCRATCHes.  If so, store away the information for
 309      later.  */
 310
 311   if (XVEC (insn, 1))
 312     {
 313       int has_hard_reg = 0;
 314
 315       for (i = XVECLEN (insn, 1) - 1; i > 0; i--)
 316         {
 317           if (GET_CODE (XVECEXP (insn, 1, i)) != CLOBBER)
 318             break;
 319
 320           if (REG_P (XEXP (XVECEXP (insn, 1, i), 0)))
 321             has_hard_reg = 1;
 322           else if (GET_CODE (XEXP (XVECEXP (insn, 1, i), 0)) != MATCH_SCRATCH)
 323             break;
 324         }
 325
 326       if (i != XVECLEN (insn, 1) - 1)
 327         {
 328           struct clobber_pat *p;
 329           struct clobber_ent *link = XNEW (struct clobber_ent);
 330           int j;
 331
 332           link->code_number = insn_code_number;
 333
 334           /* See if any previous CLOBBER_LIST entry is the same as this
 335              one.  */
 336
 337           for (p = clobber_list; p; p = p->next)
 338             {
 339               if (p->first_clobber != i + 1
 340                   || XVECLEN (p->pattern, 1) != XVECLEN (insn, 1))
 341                 continue;
 342
 343               for (j = i + 1; j < XVECLEN (insn, 1); j++)
 344                 {
 345                   rtx old_rtx = XEXP (XVECEXP (p->pattern, 1, j), 0);
 346                   rtx new_rtx = XEXP (XVECEXP (insn, 1, j), 0);
 347
 348                   /* OLD and NEW_INSN are the same if both are to be a SCRATCH
 349                      of the same mode,
 350                      or if both are registers of the same mode and number.  */
 351                   if (! (GET_MODE (old_rtx) == GET_MODE (new_rtx)
 352                          && ((GET_CODE (old_rtx) == MATCH_SCRATCH
 353                               && GET_CODE (new_rtx) == MATCH_SCRATCH)
 354                              || (REG_P (old_rtx) && REG_P (new_rtx)
 355                                  && REGNO (old_rtx) == REGNO (new_rtx)))))
 356                     break;
 357                 }
 358
 359               if (j == XVECLEN (insn, 1))
 360                 break;
 361             }
 362
 363           if (p == 0)
 364             {
 365               p = XNEW (struct clobber_pat);
 366
 367               p->insns = 0;
 368               p->pattern = insn;
 369               p->first_clobber = i + 1;
 370               p->next = clobber_list;
 371               p->has_hard_reg = has_hard_reg;
 372               clobber_list = p;
 373             }
 374
 375           link->next = p->insns;
 376           p->insns = link;
 377         }
 378     }
 379
 380   /* Don't mention instructions whose names are the null string
 381      or begin with '*'.  They are in the machine description just
 382      to be recognized.  */
 383   if (XSTR (insn, 0)[0] == 0 || XSTR (insn, 0)[0] == '*')
 384     return;
 385
 386   printf ("/* %s:%d */\n", read_md_filename, lineno);
 387
 388   /* Find out how many operands this function has.  */
 389   get_pattern_stats (&stats, XVEC (insn, 1));
 390   if (stats.max_dup_opno > stats.max_opno)
 391     fatal ("match_dup operand number has no match_operand");
 392
 393   /* Output the function name and argument declarations.  */
 394   printf ("rtx\ngen_%s (", XSTR (insn, 0));
 395   if (stats.num_generator_args)
 396     for (i = 0; i < stats.num_generator_args; i++)
 397       if (i)
 398         printf (",\n\trtx operand%d ATTRIBUTE_UNUSED", i);
 399       else
 400         printf ("rtx operand%d ATTRIBUTE_UNUSED", i);
 401   else
 402     printf ("void");
 403   printf (")\n");
 404   printf ("{\n");
 405
 406   /* Output code to construct and return the rtl for the instruction body.  */
 407
 408   rtx pattern = add_implicit_parallel (XVEC (insn, 1));
 409   /* ??? This is the traditional behavior, but seems suspect.  */
 410   char *used = (XVECLEN (insn, 1) == 1
 411                 ? NULL
 412                 : XCNEWVEC (char, stats.num_generator_args));
 413   printf ("  return ");
 414   gen_exp (pattern, DEFINE_INSN, used);
 415   printf (";\n}\n\n");
 416   XDELETEVEC (used);
 417 }
 418 \f
 419 /* Generate the `gen_...' function for a DEFINE_EXPAND.  */
 420
 421 static void
 422 gen_expand (rtx expand)
 423 {
 424   struct pattern_stats stats;
 425   int i;
 426   char *used;
 427
 428   if (strlen (XSTR (expand, 0)) == 0)
 429     fatal ("define_expand lacks a name");
 430   if (XVEC (expand, 1) == 0)
 431     fatal ("define_expand for %s lacks a pattern", XSTR (expand, 0));
 432
 433   /* Find out how many operands this function has.  */
 434   get_pattern_stats (&stats, XVEC (expand, 1));
 435
 436   /* Output the function name and argument declarations.  */
 437   printf ("rtx\ngen_%s (", XSTR (expand, 0));
 438   if (stats.num_generator_args)
 439     for (i = 0; i < stats.num_generator_args; i++)
 440       if (i)
 441         printf (",\n\trtx operand%d", i);
 442       else
 443         printf ("rtx operand%d", i);
 444   else
 445     printf ("void");
 446   printf (")\n");
 447   printf ("{\n");
 448
 449   /* If we don't have any C code to write, only one insn is being written,
 450      and no MATCH_DUPs are present, we can just return the desired insn
 451      like we do for a DEFINE_INSN.  This saves memory.  */
 452   if ((XSTR (expand, 3) == 0 || *XSTR (expand, 3) == '\0')
 453       && stats.max_opno >= stats.max_dup_opno
 454       && XVECLEN (expand, 1) == 1)
 455     {
 456       printf ("  return ");
 457       gen_exp (XVECEXP (expand, 1, 0), DEFINE_EXPAND, NULL);
 458       printf (";\n}\n\n");
 459       return;
 460     }
 461
 462   /* For each operand referred to only with MATCH_DUPs,
 463      make a local variable.  */
 464   for (i = stats.num_generator_args; i <= stats.max_dup_opno; i++)
 465     printf ("  rtx operand%d;\n", i);
 466   for (; i <= stats.max_scratch_opno; i++)
 467     printf ("  rtx operand%d ATTRIBUTE_UNUSED;\n", i);
 468   printf ("  rtx_insn *_val = 0;\n");
 469   printf ("  start_sequence ();\n");
 470
 471   /* The fourth operand of DEFINE_EXPAND is some code to be executed
 472      before the actual construction.
 473      This code expects to refer to `operands'
 474      just as the output-code in a DEFINE_INSN does,
 475      but here `operands' is an automatic array.
 476      So copy the operand values there before executing it.  */
 477   if (XSTR (expand, 3) && *XSTR (expand, 3))
 478     {
 479       printf ("  {\n");
 480       if (stats.num_operand_vars > 0)
 481         printf ("    rtx operands[%d];\n", stats.num_operand_vars);
 482
 483       /* Output code to copy the arguments into `operands'.  */
 484       for (i = 0; i < stats.num_generator_args; i++)
 485         printf ("    operands[%d] = operand%d;\n", i, i);
 486
 487       /* Output the special code to be executed before the sequence
 488          is generated.  */
 489       print_md_ptr_loc (XSTR (expand, 3));
 490       printf ("%s\n", XSTR (expand, 3));
 491
 492       /* Output code to copy the arguments back out of `operands'
 493          (unless we aren't going to use them at all).  */
 494       if (XVEC (expand, 1) != 0)
 495         {
 496           for (i = 0; i < stats.num_operand_vars; i++)
 497             {
 498               printf ("    operand%d = operands[%d];\n", i, i);
 499               printf ("    (void) operand%d;\n", i);
 500             }
 501         }
 502       printf ("  }\n");
 503     }
 504
 505   used = XCNEWVEC (char, stats.num_operand_vars);
 506   gen_emit_seq (XVEC (expand, 1), used);
 507   XDELETEVEC (used);
 508
 509   /* Call `get_insns' to extract the list of all the
 510      insns emitted within this gen_... function.  */
 511
 512   printf ("  _val = get_insns ();\n");
 513   printf ("  end_sequence ();\n");
 514   printf ("  return _val;\n}\n\n");
 515 }
 516
 517 /* Like gen_expand, but generates insns resulting from splitting SPLIT.  */
 518
 519 static void
 520 gen_split (rtx split)
 521 {
 522   struct pattern_stats stats;
 523   int i;
 524   const char *const name =
 525     ((GET_CODE (split) == DEFINE_PEEPHOLE2) ? "peephole2" : "split");
 526   const char *unused;
 527   char *used;
 528
 529   if (XVEC (split, 0) == 0)
 530     fatal ("define_%s (definition %d) lacks a pattern", name,
 531            insn_index_number);
 532   else if (XVEC (split, 2) == 0)
 533     fatal ("define_%s (definition %d) lacks a replacement pattern", name,
 534            insn_index_number);
 535
 536   /* Find out how many operands this function has.  */
 537
 538   get_pattern_stats (&stats, XVEC (split, 2));
 539   unused = (stats.num_operand_vars == 0 ? " ATTRIBUTE_UNUSED" : "");
 540   used = XCNEWVEC (char, stats.num_operand_vars);
 541
 542   /* Output the prototype, function name and argument declarations.  */
 543   if (GET_CODE (split) == DEFINE_PEEPHOLE2)
 544     {
 545       printf ("extern rtx_insn *gen_%s_%d (rtx_insn *, rtx *);\n",
 546               name, insn_code_number);
 547       printf ("rtx_insn *\ngen_%s_%d (rtx_insn *curr_insn ATTRIBUTE_UNUSED, rtx *operands%s)\n",
 548               name, insn_code_number, unused);
 549     }
 550   else
 551     {
 552       printf ("extern rtx_insn *gen_split_%d (rtx_insn *, rtx *);\n",
 553               insn_code_number);
 554       printf ("rtx_insn *\ngen_split_%d "
 555               "(rtx_insn *curr_insn ATTRIBUTE_UNUSED, rtx *operands%s)\n",
 556               insn_code_number, unused);
 557     }
 558   printf ("{\n");
 559
 560   /* Declare all local variables.  */
 561   for (i = 0; i < stats.num_operand_vars; i++)
 562     printf ("  rtx operand%d;\n", i);
 563   printf ("  rtx_insn *_val = NULL;\n");
 564
 565   if (GET_CODE (split) == DEFINE_PEEPHOLE2)
 566     output_peephole2_scratches (split);
 567
 568   printf ("  if (dump_file)\n");
 569   printf ("    fprintf (dump_file, \"Splitting with gen_%s_%d\\n\");\n",
 570           name, insn_code_number);
 571
 572   printf ("  start_sequence ();\n");
 573
 574   /* The fourth operand of DEFINE_SPLIT is some code to be executed
 575      before the actual construction.  */
 576
 577   if (XSTR (split, 3))
 578     {
 579       print_md_ptr_loc (XSTR (split, 3));
 580       printf ("%s\n", XSTR (split, 3));
 581     }
 582
 583   /* Output code to copy the arguments back out of `operands'  */
 584   for (i = 0; i < stats.num_operand_vars; i++)
 585     {
 586       printf ("  operand%d = operands[%d];\n", i, i);
 587       printf ("  (void) operand%d;\n", i);
 588     }
 589
 590   gen_emit_seq (XVEC (split, 2), used);
 591
 592   /* Call `get_insns' to make a list of all the
 593      insns emitted within this gen_... function.  */
 594
 595   printf ("  _val = get_insns ();\n");
 596   printf ("  end_sequence ();\n");
 597   printf ("  return _val;\n}\n\n");
 598
 599   free (used);
 600 }
 601 \f
 602 /* Write a function, `add_clobbers', that is given a PARALLEL of sufficient
 603    size for the insn and an INSN_CODE, and inserts the required CLOBBERs at
 604    the end of the vector.  */
 605
 606 static void
 607 output_add_clobbers (void)
 608 {
 609   struct clobber_pat *clobber;
 610   struct clobber_ent *ent;
 611   int i;
 612
 613   printf ("\n\nvoid\nadd_clobbers (rtx pattern ATTRIBUTE_UNUSED, int insn_code_number)\n");
 614   printf ("{\n");
 615   printf ("  switch (insn_code_number)\n");
 616   printf ("    {\n");
 617
 618   for (clobber = clobber_list; clobber; clobber = clobber->next)
 619     {
 620       for (ent = clobber->insns; ent; ent = ent->next)
 621         printf ("    case %d:\n", ent->code_number);
 622
 623       for (i = clobber->first_clobber; i < XVECLEN (clobber->pattern, 1); i++)
 624         {
 625           printf ("      XVECEXP (pattern, 0, %d) = ", i);
 626           gen_exp (XVECEXP (clobber->pattern, 1, i),
 627                    GET_CODE (clobber->pattern), NULL);
 628           printf (";\n");
 629         }
 630
 631       printf ("      break;\n\n");
 632     }
 633
 634   printf ("    default:\n");
 635   printf ("      gcc_unreachable ();\n");
 636   printf ("    }\n");
 637   printf ("}\n");
 638 }
 639 \f
 640 /* Write a function, `added_clobbers_hard_reg_p' that is given an insn_code
 641    number that will have clobbers added (as indicated by `recog') and returns
 642    1 if those include a clobber of a hard reg or 0 if all of them just clobber
 643    SCRATCH.  */
 644
 645 static void
 646 output_added_clobbers_hard_reg_p (void)
 647 {
 648   struct clobber_pat *clobber;
 649   struct clobber_ent *ent;
 650   int clobber_p, used;
 651
 652   printf ("\n\nint\nadded_clobbers_hard_reg_p (int insn_code_number)\n");
 653   printf ("{\n");
 654   printf ("  switch (insn_code_number)\n");
 655   printf ("    {\n");
 656
 657   for (clobber_p = 0; clobber_p <= 1; clobber_p++)
 658     {
 659       used = 0;
 660       for (clobber = clobber_list; clobber; clobber = clobber->next)
 661         if (clobber->has_hard_reg == clobber_p)
 662           for (ent = clobber->insns; ent; ent = ent->next)
 663             {
 664               printf ("    case %d:\n", ent->code_number);
 665               used++;
 666             }
 667
 668       if (used)
 669         printf ("      return %d;\n\n", clobber_p);
 670     }
 671
 672   printf ("    default:\n");
 673   printf ("      gcc_unreachable ();\n");
 674   printf ("    }\n");
 675   printf ("}\n");
 676 }
 677 \f
 678 /* Generate code to invoke find_free_register () as needed for the
 679    scratch registers used by the peephole2 pattern in SPLIT.  */
 680
 681 static void
 682 output_peephole2_scratches (rtx split)
 683 {
 684   int i;
 685   int insn_nr = 0;
 686   bool first = true;
 687
 688   for (i = 0; i < XVECLEN (split, 0); i++)
 689     {
 690       rtx elt = XVECEXP (split, 0, i);
 691       if (GET_CODE (elt) == MATCH_SCRATCH)
 692         {
 693           int last_insn_nr = insn_nr;
 694           int cur_insn_nr = insn_nr;
 695           int j;
 696           for (j = i + 1; j < XVECLEN (split, 0); j++)
 697             if (GET_CODE (XVECEXP (split, 0, j)) == MATCH_DUP)
 698               {
 699                 if (XINT (XVECEXP (split, 0, j), 0) == XINT (elt, 0))
 700                   last_insn_nr = cur_insn_nr;
 701               }
 702             else if (GET_CODE (XVECEXP (split, 0, j)) != MATCH_SCRATCH)
 703               cur_insn_nr++;
 704
 705           if (first)
 706             {
 707               printf ("  HARD_REG_SET _regs_allocated;\n");
 708               printf ("  CLEAR_HARD_REG_SET (_regs_allocated);\n");
 709               first = false;
 710             }
 711
 712           printf ("  if ((operands[%d] = peep2_find_free_register (%d, %d, \"%s\", %smode, &_regs_allocated)) == NULL_RTX)\n\
 713     return NULL;\n",
 714                   XINT (elt, 0),
 715                   insn_nr, last_insn_nr,
 716                   XSTR (elt, 1),
 717                   GET_MODE_NAME (GET_MODE (elt)));
 718
 719         }
 720       else if (GET_CODE (elt) != MATCH_DUP)
 721         insn_nr++;
 722     }
 723 }
 724
 725 int
 726 main (int argc, char **argv)
 727 {
 728   rtx desc;
 729
 730   progname = "genemit";
 731
 732   if (!init_rtx_reader_args (argc, argv))
 733     return (FATAL_EXIT_CODE);
 734
 735   /* Assign sequential codes to all entries in the machine description
 736      in parallel with the tables in insn-output.c.  */
 737
 738   insn_code_number = 0;
 739   insn_index_number = 0;
 740
 741   printf ("/* Generated automatically by the program `genemit'\n\
 742 from the machine description file `md'.  */\n\n");
 743
 744   printf ("#include \"config.h\"\n");
 745   printf ("#include \"system.h\"\n");
 746   printf ("#include \"coretypes.h\"\n");
 747   printf ("#include \"tm.h\"\n");
 748   printf ("#include \"input.h\"\n");
 749   printf ("#include \"alias.h\"\n");
 750   printf ("#include \"symtab.h\"\n");
 751   printf ("#include \"tree.h\"\n");
 752   printf ("#include \"varasm.h\"\n");
 753   printf ("#include \"stor-layout.h\"\n");
 754   printf ("#include \"calls.h\"\n");
 755   printf ("#include \"rtl.h\"\n");
 756   printf ("#include \"tm_p.h\"\n");
 757   printf ("#include \"hard-reg-set.h\"\n");
 758   printf ("#include \"function.h\"\n");
 759   printf ("#include \"flags.h\"\n");
 760   printf ("#include \"insn-config.h\"\n");
 761   printf ("#include \"expmed.h\"\n");
 762   printf ("#include \"dojump.h\"\n");
 763   printf ("#include \"explow.h\"\n");
 764   printf ("#include \"emit-rtl.h\"\n");
 765   printf ("#include \"stmt.h\"\n");
 766   printf ("#include \"expr.h\"\n");
 767   printf ("#include \"insn-codes.h\"\n");
 768   printf ("#include \"optabs.h\"\n");
 769   printf ("#include \"dfp.h\"\n");
 770   printf ("#include \"output.h\"\n");
 771   printf ("#include \"recog.h\"\n");
 772   printf ("#include \"predict.h\"\n");
 773   printf ("#include \"basic-block.h\"\n");
 774   printf ("#include \"resource.h\"\n");
 775   printf ("#include \"reload.h\"\n");
 776   printf ("#include \"diagnostic-core.h\"\n");
 777   printf ("#include \"regs.h\"\n");
 778   printf ("#include \"tm-constrs.h\"\n");
 779   printf ("#include \"ggc.h\"\n");
 780   printf ("#include \"basic-block.h\"\n");
 781   printf ("#include \"dumpfile.h\"\n");
 782   printf ("#include \"target.h\"\n\n");
 783   printf ("#define FAIL return (end_sequence (), _val)\n");
 784   printf ("#define DONE return (_val = get_insns (), end_sequence (), _val)\n\n");
 785
 786   /* Read the machine description.  */
 787
 788   while (1)
 789     {
 790       int line_no;
 791
 792       desc = read_md_rtx (&line_no, &insn_code_number);
 793       if (desc == NULL)
 794         break;
 795
 796       switch (GET_CODE (desc))
 797         {
 798         case DEFINE_INSN:
 799           gen_insn (desc, line_no);
 800           break;
 801
 802         case DEFINE_EXPAND:
 803           printf ("/* %s:%d */\n", read_md_filename, line_no);
 804           gen_expand (desc);
 805           break;
 806
 807         case DEFINE_SPLIT:
 808           printf ("/* %s:%d */\n", read_md_filename, line_no);
 809           gen_split (desc);
 810           break;
 811
 812         case DEFINE_PEEPHOLE2:
 813           printf ("/* %s:%d */\n", read_md_filename, line_no);
 814           gen_split (desc);
 815           break;
 816
 817         default:
 818           break;
 819         }
 820       ++insn_index_number;
 821     }
 822
 823   /* Write out the routines to add CLOBBERs to a pattern and say whether they
 824      clobber a hard reg.  */
 825   output_add_clobbers ();
 826   output_added_clobbers_hard_reg_p ();
 827
 828   fflush (stdout);
 829   return (ferror (stdout) != 0 ? FATAL_EXIT_CODE : SUCCESS_EXIT_CODE);
 830 }