gcc/gensupport.c

   1 /* Support routines for the various generation passes.
   2    Copyright (C) 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009
   3    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
   8    under the terms of the GNU General Public License as published by
   9    the Free Software Foundation; either version 3, or (at your option)
  10    any later version.
  11
  12    GCC is distributed in the hope that it will be useful, but WITHOUT
  13    ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  14    or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public
  15    License for more details.
  16
  17    You should have received a copy of the GNU General Public License
  18    along with GCC; see the file COPYING3.  If not see
  19    <http://www.gnu.org/licenses/>.  */
  20
  21 #include "bconfig.h"
  22 #include "system.h"
  23 #include "coretypes.h"
  24 #include "tm.h"
  25 #include "rtl.h"
  26 #include "obstack.h"
  27 #include "errors.h"
  28 #include "hashtab.h"
  29 #include "gensupport.h"
  30
  31
  32 /* In case some macros used by files we include need it, define this here.  */
  33 int target_flags;
  34
  35 int insn_elision = 1;
  36
  37 const char *in_fname;
  38
  39 /* This callback will be invoked whenever an rtl include directive is
  40    processed.  To be used for creation of the dependency file.  */
  41 void (*include_callback) (const char *);
  42
  43 static struct obstack obstack;
  44 struct obstack *rtl_obstack = &obstack;
  45
  46 static int sequence_num;
  47 static int errors;
  48
  49 static int predicable_default;
  50 static const char *predicable_true;
  51 static const char *predicable_false;
  52
  53 static htab_t condition_table;
  54
  55 static char *base_dir = NULL;
  56
  57 /* We initially queue all patterns, process the define_insn and
  58    define_cond_exec patterns, then return them one at a time.  */
  59
  60 struct queue_elem
  61 {
  62   rtx data;
  63   const char *filename;
  64   int lineno;
  65   struct queue_elem *next;
  66   /* In a DEFINE_INSN that came from a DEFINE_INSN_AND_SPLIT, SPLIT
  67      points to the generated DEFINE_SPLIT.  */
  68   struct queue_elem *split;
  69 };
  70
  71 static struct queue_elem *define_attr_queue;
  72 static struct queue_elem **define_attr_tail = &define_attr_queue;
  73 static struct queue_elem *define_pred_queue;
  74 static struct queue_elem **define_pred_tail = &define_pred_queue;
  75 static struct queue_elem *define_insn_queue;
  76 static struct queue_elem **define_insn_tail = &define_insn_queue;
  77 static struct queue_elem *define_cond_exec_queue;
  78 static struct queue_elem **define_cond_exec_tail = &define_cond_exec_queue;
  79 static struct queue_elem *other_queue;
  80 static struct queue_elem **other_tail = &other_queue;
  81
  82 static struct queue_elem *queue_pattern (rtx, struct queue_elem ***,
  83                                          const char *, int);
  84
  85 /* Current maximum length of directory names in the search path
  86    for include files.  (Altered as we get more of them.)  */
  87
  88 size_t max_include_len;
  89
  90 struct file_name_list
  91   {
  92     struct file_name_list *next;
  93     const char *fname;
  94   };
  95
  96 struct file_name_list *first_dir_md_include = 0;  /* First dir to search */
  97         /* First dir to search for <file> */
  98 struct file_name_list *first_bracket_include = 0;
  99 struct file_name_list *last_dir_md_include = 0;        /* Last in chain */
 100
 101 static void remove_constraints (rtx);
 102 static void process_rtx (rtx, int);
 103
 104 static int is_predicable (struct queue_elem *);
 105 static void identify_predicable_attribute (void);
 106 static int n_alternatives (const char *);
 107 static void collect_insn_data (rtx, int *, int *);
 108 static rtx alter_predicate_for_insn (rtx, int, int, int);
 109 static const char *alter_test_for_insn (struct queue_elem *,
 110                                         struct queue_elem *);
 111 static char *shift_output_template (char *, const char *, int);
 112 static const char *alter_output_for_insn (struct queue_elem *,
 113                                           struct queue_elem *,
 114                                           int, int);
 115 static void process_one_cond_exec (struct queue_elem *);
 116 static void process_define_cond_exec (void);
 117 static void process_include (rtx, int);
 118 static char *save_string (const char *, int);
 119 static void init_predicate_table (void);
 120 static void record_insn_name (int, const char *);
 121 \f
 122 void
 123 message_with_line (int lineno, const char *msg, ...)
 124 {
 125   va_list ap;
 126
 127   va_start (ap, msg);
 128
 129   fprintf (stderr, "%s:%d: ", read_rtx_filename, lineno);
 130   vfprintf (stderr, msg, ap);
 131   fputc ('\n', stderr);
 132
 133   va_end (ap);
 134 }
 135
 136 /* Make a version of gen_rtx_CONST_INT so that GEN_INT can be used in
 137    the gensupport programs.  */
 138
 139 rtx
 140 gen_rtx_CONST_INT (enum machine_mode ARG_UNUSED (mode),
 141                    HOST_WIDE_INT arg)
 142 {
 143   rtx rt = rtx_alloc (CONST_INT);
 144
 145   XWINT (rt, 0) = arg;
 146   return rt;
 147 }
 148 \f
 149 /* Queue PATTERN on LIST_TAIL.  Return the address of the new queue
 150    element.  */
 151
 152 static struct queue_elem *
 153 queue_pattern (rtx pattern, struct queue_elem ***list_tail,
 154                const char *filename, int lineno)
 155 {
 156   struct queue_elem *e = XNEW(struct queue_elem);
 157   e->data = pattern;
 158   e->filename = filename;
 159   e->lineno = lineno;
 160   e->next = NULL;
 161   e->split = NULL;
 162   **list_tail = e;
 163   *list_tail = &e->next;
 164   return e;
 165 }
 166
 167 /* Recursively remove constraints from an rtx.  */
 168
 169 static void
 170 remove_constraints (rtx part)
 171 {
 172   int i, j;
 173   const char *format_ptr;
 174
 175   if (part == 0)
 176     return;
 177
 178   if (GET_CODE (part) == MATCH_OPERAND)
 179     XSTR (part, 2) = "";
 180   else if (GET_CODE (part) == MATCH_SCRATCH)
 181     XSTR (part, 1) = "";
 182
 183   format_ptr = GET_RTX_FORMAT (GET_CODE (part));
 184
 185   for (i = 0; i < GET_RTX_LENGTH (GET_CODE (part)); i++)
 186     switch (*format_ptr++)
 187       {
 188       case 'e':
 189       case 'u':
 190         remove_constraints (XEXP (part, i));
 191         break;
 192       case 'E':
 193         if (XVEC (part, i) != NULL)
 194           for (j = 0; j < XVECLEN (part, i); j++)
 195             remove_constraints (XVECEXP (part, i, j));
 196         break;
 197       }
 198 }
 199
 200 /* Process an include file assuming that it lives in gcc/config/{target}/
 201    if the include looks like (include "file").  */
 202
 203 static void
 204 process_include (rtx desc, int lineno)
 205 {
 206   const char *filename = XSTR (desc, 0);
 207   const char *old_filename;
 208   int old_lineno;
 209   char *pathname;
 210   FILE *input_file;
 211
 212   /* If specified file name is absolute, skip the include stack.  */
 213   if (! IS_ABSOLUTE_PATH (filename))
 214     {
 215       struct file_name_list *stackp;
 216
 217       /* Search directory path, trying to open the file.  */
 218       for (stackp = first_dir_md_include; stackp; stackp = stackp->next)
 219         {
 220           static const char sep[2] = { DIR_SEPARATOR, '\0' };
 221
 222           pathname = concat (stackp->fname, sep, filename, NULL);
 223           input_file = fopen (pathname, "r");
 224           if (input_file != NULL)
 225             goto success;
 226           free (pathname);
 227         }
 228     }
 229
 230   if (base_dir)
 231     pathname = concat (base_dir, filename, NULL);
 232   else
 233     pathname = xstrdup (filename);
 234   input_file = fopen (pathname, "r");
 235   if (input_file == NULL)
 236     {
 237       free (pathname);
 238       message_with_line (lineno, "include file `%s' not found", filename);
 239       errors = 1;
 240       return;
 241     }
 242  success:
 243
 244   /* Save old cursor; setup new for the new file.  Note that "lineno" the
 245      argument to this function is the beginning of the include statement,
 246      while read_rtx_lineno has already been advanced.  */
 247   old_filename = read_rtx_filename;
 248   old_lineno = read_rtx_lineno;
 249   read_rtx_filename = pathname;
 250   read_rtx_lineno = 1;
 251
 252   if (include_callback)
 253     include_callback (pathname);
 254
 255   /* Read the entire file.  */
 256   while (read_rtx (input_file, &desc, &lineno))
 257     process_rtx (desc, lineno);
 258
 259   /* Do not free pathname.  It is attached to the various rtx queue
 260      elements.  */
 261
 262   read_rtx_filename = old_filename;
 263   read_rtx_lineno = old_lineno;
 264
 265   fclose (input_file);
 266 }
 267
 268 /* Process a top level rtx in some way, queuing as appropriate.  */
 269
 270 static void
 271 process_rtx (rtx desc, int lineno)
 272 {
 273   switch (GET_CODE (desc))
 274     {
 275     case DEFINE_INSN:
 276       queue_pattern (desc, &define_insn_tail, read_rtx_filename, lineno);
 277       break;
 278
 279     case DEFINE_COND_EXEC:
 280       queue_pattern (desc, &define_cond_exec_tail, read_rtx_filename, lineno);
 281       break;
 282
 283     case DEFINE_ATTR:
 284       queue_pattern (desc, &define_attr_tail, read_rtx_filename, lineno);
 285       break;
 286
 287     case DEFINE_PREDICATE:
 288     case DEFINE_SPECIAL_PREDICATE:
 289     case DEFINE_CONSTRAINT:
 290     case DEFINE_REGISTER_CONSTRAINT:
 291     case DEFINE_MEMORY_CONSTRAINT:
 292     case DEFINE_ADDRESS_CONSTRAINT:
 293       queue_pattern (desc, &define_pred_tail, read_rtx_filename, lineno);
 294       break;
 295
 296     case INCLUDE:
 297       process_include (desc, lineno);
 298       break;
 299
 300     case DEFINE_INSN_AND_SPLIT:
 301       {
 302         const char *split_cond;
 303         rtx split;
 304         rtvec attr;
 305         int i;
 306         struct queue_elem *insn_elem;
 307         struct queue_elem *split_elem;
 308
 309         /* Create a split with values from the insn_and_split.  */
 310         split = rtx_alloc (DEFINE_SPLIT);
 311
 312         i = XVECLEN (desc, 1);
 313         XVEC (split, 0) = rtvec_alloc (i);
 314         while (--i >= 0)
 315           {
 316             XVECEXP (split, 0, i) = copy_rtx (XVECEXP (desc, 1, i));
 317             remove_constraints (XVECEXP (split, 0, i));
 318           }
 319
 320         /* If the split condition starts with "&&", append it to the
 321            insn condition to create the new split condition.  */
 322         split_cond = XSTR (desc, 4);
 323         if (split_cond[0] == '&' && split_cond[1] == '&')
 324           {
 325             copy_rtx_ptr_loc (split_cond + 2, split_cond);
 326             split_cond = join_c_conditions (XSTR (desc, 2), split_cond + 2);
 327           }
 328         XSTR (split, 1) = split_cond;
 329         XVEC (split, 2) = XVEC (desc, 5);
 330         XSTR (split, 3) = XSTR (desc, 6);
 331
 332         /* Fix up the DEFINE_INSN.  */
 333         attr = XVEC (desc, 7);
 334         PUT_CODE (desc, DEFINE_INSN);
 335         XVEC (desc, 4) = attr;
 336
 337         /* Queue them.  */
 338         insn_elem
 339           = queue_pattern (desc, &define_insn_tail, read_rtx_filename,
 340                            lineno);
 341         split_elem
 342           = queue_pattern (split, &other_tail, read_rtx_filename, lineno);
 343         insn_elem->split = split_elem;
 344         break;
 345       }
 346
 347     default:
 348       queue_pattern (desc, &other_tail, read_rtx_filename, lineno);
 349       break;
 350     }
 351 }
 352 \f
 353 /* Return true if attribute PREDICABLE is true for ELEM, which holds
 354    a DEFINE_INSN.  */
 355
 356 static int
 357 is_predicable (struct queue_elem *elem)
 358 {
 359   rtvec vec = XVEC (elem->data, 4);
 360   const char *value;
 361   int i;
 362
 363   if (! vec)
 364     return predicable_default;
 365
 366   for (i = GET_NUM_ELEM (vec) - 1; i >= 0; --i)
 367     {
 368       rtx sub = RTVEC_ELT (vec, i);
 369       switch (GET_CODE (sub))
 370         {
 371         case SET_ATTR:
 372           if (strcmp (XSTR (sub, 0), "predicable") == 0)
 373             {
 374               value = XSTR (sub, 1);
 375               goto found;
 376             }
 377           break;
 378
 379         case SET_ATTR_ALTERNATIVE:
 380           if (strcmp (XSTR (sub, 0), "predicable") == 0)
 381             {
 382               message_with_line (elem->lineno,
 383                                  "multiple alternatives for `predicable'");
 384               errors = 1;
 385               return 0;
 386             }
 387           break;
 388
 389         case SET:
 390           if (GET_CODE (SET_DEST (sub)) != ATTR
 391               || strcmp (XSTR (SET_DEST (sub), 0), "predicable") != 0)
 392             break;
 393           sub = SET_SRC (sub);
 394           if (GET_CODE (sub) == CONST_STRING)
 395             {
 396               value = XSTR (sub, 0);
 397               goto found;
 398             }
 399
 400           /* ??? It would be possible to handle this if we really tried.
 401              It's not easy though, and I'm not going to bother until it
 402              really proves necessary.  */
 403           message_with_line (elem->lineno,
 404                              "non-constant value for `predicable'");
 405           errors = 1;
 406           return 0;
 407
 408         default:
 409           gcc_unreachable ();
 410         }
 411     }
 412
 413   return predicable_default;
 414
 415  found:
 416   /* Verify that predicability does not vary on the alternative.  */
 417   /* ??? It should be possible to handle this by simply eliminating
 418      the non-predicable alternatives from the insn.  FRV would like
 419      to do this.  Delay this until we've got the basics solid.  */
 420   if (strchr (value, ',') != NULL)
 421     {
 422       message_with_line (elem->lineno,
 423                          "multiple alternatives for `predicable'");
 424       errors = 1;
 425       return 0;
 426     }
 427
 428   /* Find out which value we're looking at.  */
 429   if (strcmp (value, predicable_true) == 0)
 430     return 1;
 431   if (strcmp (value, predicable_false) == 0)
 432     return 0;
 433
 434   message_with_line (elem->lineno,
 435                      "unknown value `%s' for `predicable' attribute",
 436                      value);
 437   errors = 1;
 438   return 0;
 439 }
 440
 441 /* Examine the attribute "predicable"; discover its boolean values
 442    and its default.  */
 443
 444 static void
 445 identify_predicable_attribute (void)
 446 {
 447   struct queue_elem *elem;
 448   char *p_true, *p_false;
 449   const char *value;
 450
 451   /* Look for the DEFINE_ATTR for `predicable', which must exist.  */
 452   for (elem = define_attr_queue; elem ; elem = elem->next)
 453     if (strcmp (XSTR (elem->data, 0), "predicable") == 0)
 454       goto found;
 455
 456   message_with_line (define_cond_exec_queue->lineno,
 457                      "attribute `predicable' not defined");
 458   errors = 1;
 459   return;
 460
 461  found:
 462   value = XSTR (elem->data, 1);
 463   p_false = xstrdup (value);
 464   p_true = strchr (p_false, ',');
 465   if (p_true == NULL || strchr (++p_true, ',') != NULL)
 466     {
 467       message_with_line (elem->lineno,
 468                          "attribute `predicable' is not a boolean");
 469       errors = 1;
 470       if (p_false)
 471         free (p_false);
 472       return;
 473     }
 474   p_true[-1] = '\0';
 475
 476   predicable_true = p_true;
 477   predicable_false = p_false;
 478
 479   switch (GET_CODE (XEXP (elem->data, 2)))
 480     {
 481     case CONST_STRING:
 482       value = XSTR (XEXP (elem->data, 2), 0);
 483       break;
 484
 485     case CONST:
 486       message_with_line (elem->lineno,
 487                          "attribute `predicable' cannot be const");
 488       errors = 1;
 489       if (p_false)
 490         free (p_false);
 491       return;
 492
 493     default:
 494       message_with_line (elem->lineno,
 495                          "attribute `predicable' must have a constant default");
 496       errors = 1;
 497       if (p_false)
 498         free (p_false);
 499       return;
 500     }
 501
 502   if (strcmp (value, p_true) == 0)
 503     predicable_default = 1;
 504   else if (strcmp (value, p_false) == 0)
 505     predicable_default = 0;
 506   else
 507     {
 508       message_with_line (elem->lineno,
 509                          "unknown value `%s' for `predicable' attribute",
 510                          value);
 511       errors = 1;
 512       if (p_false)
 513         free (p_false);
 514     }
 515 }
 516
 517 /* Return the number of alternatives in constraint S.  */
 518
 519 static int
 520 n_alternatives (const char *s)
 521 {
 522   int n = 1;
 523
 524   if (s)
 525     while (*s)
 526       n += (*s++ == ',');
 527
 528   return n;
 529 }
 530
 531 /* Determine how many alternatives there are in INSN, and how many
 532    operands.  */
 533
 534 static void
 535 collect_insn_data (rtx pattern, int *palt, int *pmax)
 536 {
 537   const char *fmt;
 538   enum rtx_code code;
 539   int i, j, len;
 540
 541   code = GET_CODE (pattern);
 542   switch (code)
 543     {
 544     case MATCH_OPERAND:
 545       i = n_alternatives (XSTR (pattern, 2));
 546       *palt = (i > *palt ? i : *palt);
 547       /* Fall through.  */
 548
 549     case MATCH_OPERATOR:
 550     case MATCH_SCRATCH:
 551     case MATCH_PARALLEL:
 552       i = XINT (pattern, 0);
 553       if (i > *pmax)
 554         *pmax = i;
 555       break;
 556
 557     default:
 558       break;
 559     }
 560
 561   fmt = GET_RTX_FORMAT (code);
 562   len = GET_RTX_LENGTH (code);
 563   for (i = 0; i < len; i++)
 564     {
 565       switch (fmt[i])
 566         {
 567         case 'e': case 'u':
 568           collect_insn_data (XEXP (pattern, i), palt, pmax);
 569           break;
 570
 571         case 'V':
 572           if (XVEC (pattern, i) == NULL)
 573             break;
 574           /* Fall through.  */
 575         case 'E':
 576           for (j = XVECLEN (pattern, i) - 1; j >= 0; --j)
 577             collect_insn_data (XVECEXP (pattern, i, j), palt, pmax);
 578           break;
 579
 580         case 'i': case 'w': case '0': case 's': case 'S': case 'T':
 581           break;
 582
 583         default:
 584           gcc_unreachable ();
 585         }
 586     }
 587 }
 588
 589 static rtx
 590 alter_predicate_for_insn (rtx pattern, int alt, int max_op, int lineno)
 591 {
 592   const char *fmt;
 593   enum rtx_code code;
 594   int i, j, len;
 595
 596   code = GET_CODE (pattern);
 597   switch (code)
 598     {
 599     case MATCH_OPERAND:
 600       {
 601         const char *c = XSTR (pattern, 2);
 602
 603         if (n_alternatives (c) != 1)
 604           {
 605             message_with_line (lineno,
 606                                "too many alternatives for operand %d",
 607                                XINT (pattern, 0));
 608             errors = 1;
 609             return NULL;
 610           }
 611
 612         /* Replicate C as needed to fill out ALT alternatives.  */
 613         if (c && *c && alt > 1)
 614           {
 615             size_t c_len = strlen (c);
 616             size_t len = alt * (c_len + 1);
 617             char *new_c = XNEWVEC(char, len);
 618
 619             memcpy (new_c, c, c_len);
 620             for (i = 1; i < alt; ++i)
 621               {
 622                 new_c[i * (c_len + 1) - 1] = ',';
 623                 memcpy (&new_c[i * (c_len + 1)], c, c_len);
 624               }
 625             new_c[len - 1] = '\0';
 626             XSTR (pattern, 2) = new_c;
 627           }
 628       }
 629       /* Fall through.  */
 630
 631     case MATCH_OPERATOR:
 632     case MATCH_SCRATCH:
 633     case MATCH_PARALLEL:
 634       XINT (pattern, 0) += max_op;
 635       break;
 636
 637     default:
 638       break;
 639     }
 640
 641   fmt = GET_RTX_FORMAT (code);
 642   len = GET_RTX_LENGTH (code);
 643   for (i = 0; i < len; i++)
 644     {
 645       rtx r;
 646
 647       switch (fmt[i])
 648         {
 649         case 'e': case 'u':
 650           r = alter_predicate_for_insn (XEXP (pattern, i), alt,
 651                                         max_op, lineno);
 652           if (r == NULL)
 653             return r;
 654           break;
 655
 656         case 'E':
 657           for (j = XVECLEN (pattern, i) - 1; j >= 0; --j)
 658             {
 659               r = alter_predicate_for_insn (XVECEXP (pattern, i, j),
 660                                             alt, max_op, lineno);
 661               if (r == NULL)
 662                 return r;
 663             }
 664           break;
 665
 666         case 'i': case 'w': case '0': case 's':
 667           break;
 668
 669         default:
 670           gcc_unreachable ();
 671         }
 672     }
 673
 674   return pattern;
 675 }
 676
 677 static const char *
 678 alter_test_for_insn (struct queue_elem *ce_elem,
 679                      struct queue_elem *insn_elem)
 680 {
 681   return join_c_conditions (XSTR (ce_elem->data, 1),
 682                             XSTR (insn_elem->data, 2));
 683 }
 684
 685 /* Adjust all of the operand numbers in SRC to match the shift they'll
 686    get from an operand displacement of DISP.  Return a pointer after the
 687    adjusted string.  */
 688
 689 static char *
 690 shift_output_template (char *dest, const char *src, int disp)
 691 {
 692   while (*src)
 693     {
 694       char c = *src++;
 695       *dest++ = c;
 696       if (c == '%')
 697         {
 698           c = *src++;
 699           if (ISDIGIT ((unsigned char) c))
 700             c += disp;
 701           else if (ISALPHA (c))
 702             {
 703               *dest++ = c;
 704               c = *src++ + disp;
 705             }
 706           *dest++ = c;
 707         }
 708     }
 709
 710   return dest;
 711 }
 712
 713 static const char *
 714 alter_output_for_insn (struct queue_elem *ce_elem,
 715                        struct queue_elem *insn_elem,
 716                        int alt, int max_op)
 717 {
 718   const char *ce_out, *insn_out;
 719   char *result, *p;
 720   size_t len, ce_len, insn_len;
 721
 722   /* ??? Could coordinate with genoutput to not duplicate code here.  */
 723
 724   ce_out = XSTR (ce_elem->data, 2);
 725   insn_out = XTMPL (insn_elem->data, 3);
 726   if (!ce_out || *ce_out == '\0')
 727     return insn_out;
 728
 729   ce_len = strlen (ce_out);
 730   insn_len = strlen (insn_out);
 731
 732   if (*insn_out == '*')
 733     /* You must take care of the predicate yourself.  */
 734     return insn_out;
 735
 736   if (*insn_out == '@')
 737     {
 738       len = (ce_len + 1) * alt + insn_len + 1;
 739       p = result = XNEWVEC(char, len);
 740
 741       do
 742         {
 743           do
 744             *p++ = *insn_out++;
 745           while (ISSPACE ((unsigned char) *insn_out));
 746
 747           if (*insn_out != '#')
 748             {
 749               p = shift_output_template (p, ce_out, max_op);
 750               *p++ = ' ';
 751             }
 752
 753           do
 754             *p++ = *insn_out++;
 755           while (*insn_out && *insn_out != '\n');
 756         }
 757       while (*insn_out);
 758       *p = '\0';
 759     }
 760   else
 761     {
 762       len = ce_len + 1 + insn_len + 1;
 763       result = XNEWVEC (char, len);
 764
 765       p = shift_output_template (result, ce_out, max_op);
 766       *p++ = ' ';
 767       memcpy (p, insn_out, insn_len + 1);
 768     }
 769
 770   return result;
 771 }
 772
 773 /* Replicate insns as appropriate for the given DEFINE_COND_EXEC.  */
 774
 775 static void
 776 process_one_cond_exec (struct queue_elem *ce_elem)
 777 {
 778   struct queue_elem *insn_elem;
 779   for (insn_elem = define_insn_queue; insn_elem ; insn_elem = insn_elem->next)
 780     {
 781       int alternatives, max_operand;
 782       rtx pred, insn, pattern, split;
 783       int i;
 784
 785       if (! is_predicable (insn_elem))
 786         continue;
 787
 788       alternatives = 1;
 789       max_operand = -1;
 790       collect_insn_data (insn_elem->data, &alternatives, &max_operand);
 791       max_operand += 1;
 792
 793       if (XVECLEN (ce_elem->data, 0) != 1)
 794         {
 795           message_with_line (ce_elem->lineno,
 796                              "too many patterns in predicate");
 797           errors = 1;
 798           return;
 799         }
 800
 801       pred = copy_rtx (XVECEXP (ce_elem->data, 0, 0));
 802       pred = alter_predicate_for_insn (pred, alternatives, max_operand,
 803                                        ce_elem->lineno);
 804       if (pred == NULL)
 805         return;
 806
 807       /* Construct a new pattern for the new insn.  */
 808       insn = copy_rtx (insn_elem->data);
 809       XSTR (insn, 0) = "";
 810       pattern = rtx_alloc (COND_EXEC);
 811       XEXP (pattern, 0) = pred;
 812       if (XVECLEN (insn, 1) == 1)
 813         {
 814           XEXP (pattern, 1) = XVECEXP (insn, 1, 0);
 815           XVECEXP (insn, 1, 0) = pattern;
 816           PUT_NUM_ELEM (XVEC (insn, 1), 1);
 817         }
 818       else
 819         {
 820           XEXP (pattern, 1) = rtx_alloc (PARALLEL);
 821           XVEC (XEXP (pattern, 1), 0) = XVEC (insn, 1);
 822           XVEC (insn, 1) = rtvec_alloc (1);
 823           XVECEXP (insn, 1, 0) = pattern;
 824         }
 825
 826       XSTR (insn, 2) = alter_test_for_insn (ce_elem, insn_elem);
 827       XTMPL (insn, 3) = alter_output_for_insn (ce_elem, insn_elem,
 828                                               alternatives, max_operand);
 829
 830       /* ??? Set `predicable' to false.  Not crucial since it's really
 831          only used here, and we won't reprocess this new pattern.  */
 832
 833       /* Put the new pattern on the `other' list so that it
 834          (a) is not reprocessed by other define_cond_exec patterns
 835          (b) appears after all normal define_insn patterns.
 836
 837          ??? B is debatable.  If one has normal insns that match
 838          cond_exec patterns, they will be preferred over these
 839          generated patterns.  Whether this matters in practice, or if
 840          it's a good thing, or whether we should thread these new
 841          patterns into the define_insn chain just after their generator
 842          is something we'll have to experiment with.  */
 843
 844       queue_pattern (insn, &other_tail, insn_elem->filename,
 845                      insn_elem->lineno);
 846
 847       if (!insn_elem->split)
 848         continue;
 849
 850       /* If the original insn came from a define_insn_and_split,
 851          generate a new split to handle the predicated insn.  */
 852       split = copy_rtx (insn_elem->split->data);
 853       /* Predicate the pattern matched by the split.  */
 854       pattern = rtx_alloc (COND_EXEC);
 855       XEXP (pattern, 0) = pred;
 856       if (XVECLEN (split, 0) == 1)
 857         {
 858           XEXP (pattern, 1) = XVECEXP (split, 0, 0);
 859           XVECEXP (split, 0, 0) = pattern;
 860           PUT_NUM_ELEM (XVEC (split, 0), 1);
 861         }
 862       else
 863         {
 864           XEXP (pattern, 1) = rtx_alloc (PARALLEL);
 865           XVEC (XEXP (pattern, 1), 0) = XVEC (split, 0);
 866           XVEC (split, 0) = rtvec_alloc (1);
 867           XVECEXP (split, 0, 0) = pattern;
 868         }
 869       /* Predicate all of the insns generated by the split.  */
 870       for (i = 0; i < XVECLEN (split, 2); i++)
 871         {
 872           pattern = rtx_alloc (COND_EXEC);
 873           XEXP (pattern, 0) = pred;
 874           XEXP (pattern, 1) = XVECEXP (split, 2, i);
 875           XVECEXP (split, 2, i) = pattern;
 876         }
 877       /* Add the new split to the queue.  */
 878       queue_pattern (split, &other_tail, read_rtx_filename,
 879                      insn_elem->split->lineno);
 880     }
 881 }
 882
 883 /* If we have any DEFINE_COND_EXEC patterns, expand the DEFINE_INSN
 884    patterns appropriately.  */
 885
 886 static void
 887 process_define_cond_exec (void)
 888 {
 889   struct queue_elem *elem;
 890
 891   identify_predicable_attribute ();
 892   if (errors)
 893     return;
 894
 895   for (elem = define_cond_exec_queue; elem ; elem = elem->next)
 896     process_one_cond_exec (elem);
 897 }
 898
 899 static char *
 900 save_string (const char *s, int len)
 901 {
 902   char *result = XNEWVEC (char, len + 1);
 903
 904   memcpy (result, s, len);
 905   result[len] = 0;
 906   return result;
 907 }
 908
 909 \f
 910 /* The entry point for initializing the reader.  */
 911
 912 int
 913 init_md_reader_args_cb (int argc, char **argv, bool (*parse_opt)(const char *))
 914 {
 915   FILE *input_file;
 916   int c, i, lineno;
 917   char *lastsl;
 918   rtx desc;
 919   bool no_more_options;
 920   bool already_read_stdin;
 921
 922   /* Unlock the stdio streams.  */
 923   unlock_std_streams ();
 924
 925   /* First we loop over all the options.  */
 926   for (i = 1; i < argc; i++)
 927     {
 928       if (argv[i][0] != '-')
 929         continue;
 930
 931       c = argv[i][1];
 932       switch (c)
 933         {
 934         case 'I':               /* Add directory to path for includes.  */
 935           {
 936             struct file_name_list *dirtmp;
 937
 938             dirtmp = XNEW (struct file_name_list);
 939             dirtmp->next = 0;   /* New one goes on the end */
 940             if (first_dir_md_include == 0)
 941               first_dir_md_include = dirtmp;
 942             else
 943               last_dir_md_include->next = dirtmp;
 944             last_dir_md_include = dirtmp;       /* Tail follows the last one */
 945             if (argv[i][1] == 'I' && argv[i][2] != 0)
 946               dirtmp->fname = argv[i] + 2;
 947             else if (i + 1 == argc)
 948               fatal ("directory name missing after -I option");
 949             else
 950               dirtmp->fname = argv[++i];
 951             if (strlen (dirtmp->fname) > max_include_len)
 952               max_include_len = strlen (dirtmp->fname);
 953           }
 954           break;
 955
 956         case '\0':
 957           /* An argument consisting of exactly one dash is a request to
 958              read stdin.  This will be handled in the second loop.  */
 959           continue;
 960
 961         case '-':
 962           /* An argument consisting of just two dashes causes option
 963              parsing to cease.  */
 964           if (argv[i][2] == '\0')
 965             goto stop_parsing_options;
 966
 967         default:
 968           /* The program may have provided a callback so it can
 969              accept its own options.  */
 970           if (parse_opt && parse_opt (argv[i]))
 971             break;
 972
 973           fatal ("invalid option `%s'", argv[i]);
 974         }
 975     }
 976
 977  stop_parsing_options:
 978
 979   /* Prepare to read input.  */
 980   condition_table = htab_create (500, hash_c_test, cmp_c_test, NULL);
 981   init_predicate_table ();
 982   obstack_init (rtl_obstack);
 983   errors = 0;
 984   sequence_num = 0;
 985   no_more_options = false;
 986   already_read_stdin = false;
 987
 988
 989   /* Now loop over all input files.  */
 990   for (i = 1; i < argc; i++)
 991     {
 992       if (argv[i][0] == '-')
 993         {
 994           if (argv[i][1] == '\0')
 995             {
 996               /* Read stdin.  */
 997               if (already_read_stdin)
 998                 fatal ("cannot read standard input twice");
 999
1000               base_dir = NULL;
1001               read_rtx_filename = in_fname = "<stdin>";
1002               read_rtx_lineno = 1;
1003               input_file = stdin;
1004               already_read_stdin = true;
1005
1006               while (read_rtx (input_file, &desc, &lineno))
1007                 process_rtx (desc, lineno);
1008               fclose (input_file);
1009               continue;
1010             }
1011           else if (argv[i][1] == '-' && argv[i][2] == '\0')
1012             {
1013               /* No further arguments are to be treated as options.  */
1014               no_more_options = true;
1015               continue;
1016             }
1017           else if (!no_more_options)
1018             continue;
1019         }
1020
1021       /* If we get here we are looking at a non-option argument, i.e.
1022          a file to be processed.  */
1023
1024       in_fname = argv[i];
1025       lastsl = strrchr (in_fname, '/');
1026       if (lastsl != NULL)
1027         base_dir = save_string (in_fname, lastsl - in_fname + 1 );
1028       else
1029         base_dir = NULL;
1030
1031       read_rtx_filename = in_fname;
1032       read_rtx_lineno = 1;
1033       input_file = fopen (in_fname, "r");
1034       if (input_file == 0)
1035         {
1036           perror (in_fname);
1037           return FATAL_EXIT_CODE;
1038         }
1039
1040       while (read_rtx (input_file, &desc, &lineno))
1041         process_rtx (desc, lineno);
1042       fclose (input_file);
1043     }
1044
1045   /* If we get to this point without having seen any files to process,
1046      read standard input now.  */
1047   if (!in_fname)
1048     {
1049       base_dir = NULL;
1050       read_rtx_filename = in_fname = "<stdin>";
1051       read_rtx_lineno = 1;
1052       input_file = stdin;
1053
1054       while (read_rtx (input_file, &desc, &lineno))
1055         process_rtx (desc, lineno);
1056       fclose (input_file);
1057     }
1058
1059   /* Process define_cond_exec patterns.  */
1060   if (define_cond_exec_queue != NULL)
1061     process_define_cond_exec ();
1062
1063   return errors ? FATAL_EXIT_CODE : SUCCESS_EXIT_CODE;
1064 }
1065
1066 /* Programs that don't have their own options can use this entry point
1067    instead.  */
1068 int
1069 init_md_reader_args (int argc, char **argv)
1070 {
1071   return init_md_reader_args_cb (argc, argv, 0);
1072 }
1073 \f
1074 /* The entry point for reading a single rtx from an md file.  */
1075
1076 rtx
1077 read_md_rtx (int *lineno, int *seqnr)
1078 {
1079   struct queue_elem **queue, *elem;
1080   rtx desc;
1081
1082  discard:
1083
1084   /* Read all patterns from a given queue before moving on to the next.  */
1085   if (define_attr_queue != NULL)
1086     queue = &define_attr_queue;
1087   else if (define_pred_queue != NULL)
1088     queue = &define_pred_queue;
1089   else if (define_insn_queue != NULL)
1090     queue = &define_insn_queue;
1091   else if (other_queue != NULL)
1092     queue = &other_queue;
1093   else
1094     return NULL_RTX;
1095
1096   elem = *queue;
1097   *queue = elem->next;
1098   desc = elem->data;
1099   read_rtx_filename = elem->filename;
1100   *lineno = elem->lineno;
1101   *seqnr = sequence_num;
1102
1103   free (elem);
1104
1105   /* Discard insn patterns which we know can never match (because
1106      their C test is provably always false).  If insn_elision is
1107      false, our caller needs to see all the patterns.  Note that the
1108      elided patterns are never counted by the sequence numbering; it
1109      it is the caller's responsibility, when insn_elision is false, not
1110      to use elided pattern numbers for anything.  */
1111   switch (GET_CODE (desc))
1112     {
1113     case DEFINE_INSN:
1114     case DEFINE_EXPAND:
1115       if (maybe_eval_c_test (XSTR (desc, 2)) != 0)
1116         sequence_num++;
1117       else if (insn_elision)
1118         goto discard;
1119
1120       /* *seqnr is used here so the name table will match caller's
1121          idea of insn numbering, whether or not elision is active.  */
1122       record_insn_name (*seqnr, XSTR (desc, 0));
1123       break;
1124
1125     case DEFINE_SPLIT:
1126     case DEFINE_PEEPHOLE:
1127     case DEFINE_PEEPHOLE2:
1128       if (maybe_eval_c_test (XSTR (desc, 1)) != 0)
1129         sequence_num++;
1130       else if (insn_elision)
1131             goto discard;
1132       break;
1133
1134     default:
1135       break;
1136     }
1137
1138   return desc;
1139 }
1140
1141 /* Helper functions for insn elision.  */
1142
1143 /* Compute a hash function of a c_test structure, which is keyed
1144    by its ->expr field.  */
1145 hashval_t
1146 hash_c_test (const void *x)
1147 {
1148   const struct c_test *a = (const struct c_test *) x;
1149   const unsigned char *base, *s = (const unsigned char *) a->expr;
1150   hashval_t hash;
1151   unsigned char c;
1152   unsigned int len;
1153
1154   base = s;
1155   hash = 0;
1156
1157   while ((c = *s++) != '\0')
1158     {
1159       hash += c + (c << 17);
1160       hash ^= hash >> 2;
1161     }
1162
1163   len = s - base;
1164   hash += len + (len << 17);
1165   hash ^= hash >> 2;
1166
1167   return hash;
1168 }
1169
1170 /* Compare two c_test expression structures.  */
1171 int
1172 cmp_c_test (const void *x, const void *y)
1173 {
1174   const struct c_test *a = (const struct c_test *) x;
1175   const struct c_test *b = (const struct c_test *) y;
1176
1177   return !strcmp (a->expr, b->expr);
1178 }
1179
1180 /* Given a string representing a C test expression, look it up in the
1181    condition_table and report whether or not its value is known
1182    at compile time.  Returns a tristate: 1 for known true, 0 for
1183    known false, -1 for unknown.  */
1184 int
1185 maybe_eval_c_test (const char *expr)
1186 {
1187   const struct c_test *test;
1188   struct c_test dummy;
1189
1190   if (expr[0] == 0)
1191     return 1;
1192
1193   dummy.expr = expr;
1194   test = (const struct c_test *)htab_find (condition_table, &dummy);
1195   if (!test)
1196     return -1;
1197   return test->value;
1198 }
1199
1200 /* Record the C test expression EXPR in the condition_table, with
1201    value VAL.  Duplicates clobber previous entries.  */
1202
1203 void
1204 add_c_test (const char *expr, int value)
1205 {
1206   struct c_test *test;
1207
1208   if (expr[0] == 0)
1209     return;
1210
1211   test = XNEW (struct c_test);
1212   test->expr = expr;
1213   test->value = value;
1214
1215   *(htab_find_slot (condition_table, test, INSERT)) = test;
1216 }
1217
1218 /* For every C test, call CALLBACK with two arguments: a pointer to
1219    the condition structure and INFO.  Stops when CALLBACK returns zero.  */
1220 void
1221 traverse_c_tests (htab_trav callback, void *info)
1222 {
1223   if (condition_table)
1224     htab_traverse (condition_table, callback, info);
1225 }
1226
1227
1228 /* Given a string, return the number of comma-separated elements in it.
1229    Return 0 for the null string.  */
1230 int
1231 n_comma_elts (const char *s)
1232 {
1233   int n;
1234
1235   if (*s == '\0')
1236     return 0;
1237
1238   for (n = 1; *s; s++)
1239     if (*s == ',')
1240       n++;
1241
1242   return n;
1243 }
1244
1245 /* Given a pointer to a (char *), return a pointer to the beginning of the
1246    next comma-separated element in the string.  Advance the pointer given
1247    to the end of that element.  Return NULL if at end of string.  Caller
1248    is responsible for copying the string if necessary.  White space between
1249    a comma and an element is ignored.  */
1250
1251 const char *
1252 scan_comma_elt (const char **pstr)
1253 {
1254   const char *start;
1255   const char *p = *pstr;
1256
1257   if (*p == ',')
1258     p++;
1259   while (ISSPACE(*p))
1260     p++;
1261
1262   if (*p == '\0')
1263     return NULL;
1264
1265   start = p;
1266
1267   while (*p != ',' && *p != '\0')
1268     p++;
1269
1270   *pstr = p;
1271   return start;
1272 }
1273
1274 /* Helper functions for define_predicate and define_special_predicate
1275    processing.  Shared between genrecog.c and genpreds.c.  */
1276
1277 static htab_t predicate_table;
1278 struct pred_data *first_predicate;
1279 static struct pred_data **last_predicate = &first_predicate;
1280
1281 static hashval_t
1282 hash_struct_pred_data (const void *ptr)
1283 {
1284   return htab_hash_string (((const struct pred_data *)ptr)->name);
1285 }
1286
1287 static int
1288 eq_struct_pred_data (const void *a, const void *b)
1289 {
1290   return !strcmp (((const struct pred_data *)a)->name,
1291                   ((const struct pred_data *)b)->name);
1292 }
1293
1294 struct pred_data *
1295 lookup_predicate (const char *name)
1296 {
1297   struct pred_data key;
1298   key.name = name;
1299   return (struct pred_data *) htab_find (predicate_table, &key);
1300 }
1301
1302 /* Record that predicate PRED can accept CODE.  */
1303
1304 void
1305 add_predicate_code (struct pred_data *pred, enum rtx_code code)
1306 {
1307   if (!pred->codes[code])
1308     {
1309       pred->num_codes++;
1310       pred->codes[code] = true;
1311
1312       if (GET_RTX_CLASS (code) != RTX_CONST_OBJ)
1313         pred->allows_non_const = true;
1314
1315       if (code != REG
1316           && code != SUBREG
1317           && code != MEM
1318           && code != CONCAT
1319           && code != PARALLEL
1320           && code != STRICT_LOW_PART)
1321         pred->allows_non_lvalue = true;
1322
1323       if (pred->num_codes == 1)
1324         pred->singleton = code;
1325       else if (pred->num_codes == 2)
1326         pred->singleton = UNKNOWN;
1327     }
1328 }
1329
1330 void
1331 add_predicate (struct pred_data *pred)
1332 {
1333   void **slot = htab_find_slot (predicate_table, pred, INSERT);
1334   if (*slot)
1335     {
1336       error ("duplicate predicate definition for '%s'", pred->name);
1337       return;
1338     }
1339   *slot = pred;
1340   *last_predicate = pred;
1341   last_predicate = &pred->next;
1342 }
1343
1344 /* This array gives the initial content of the predicate table.  It
1345    has entries for all predicates defined in recog.c.  */
1346
1347 struct std_pred_table
1348 {
1349   const char *name;
1350   bool special;
1351   bool allows_const_p;
1352   RTX_CODE codes[NUM_RTX_CODE];
1353 };
1354
1355 static const struct std_pred_table std_preds[] = {
1356   {"general_operand", false, true, {SUBREG, REG, MEM}},
1357   {"address_operand", true, true, {SUBREG, REG, MEM, PLUS, MINUS, MULT}},
1358   {"register_operand", false, false, {SUBREG, REG}},
1359   {"pmode_register_operand", true, false, {SUBREG, REG}},
1360   {"scratch_operand", false, false, {SCRATCH, REG}},
1361   {"immediate_operand", false, true, {UNKNOWN}},
1362   {"const_int_operand", false, false, {CONST_INT}},
1363   {"const_double_operand", false, false, {CONST_INT, CONST_DOUBLE}},
1364   {"nonimmediate_operand", false, false, {SUBREG, REG, MEM}},
1365   {"nonmemory_operand", false, true, {SUBREG, REG}},
1366   {"push_operand", false, false, {MEM}},
1367   {"pop_operand", false, false, {MEM}},
1368   {"memory_operand", false, false, {SUBREG, MEM}},
1369   {"indirect_operand", false, false, {SUBREG, MEM}},
1370   {"ordered_comparison_operator", false, false, {EQ, NE,
1371                                                  LE, LT, GE, GT,
1372                                                  LEU, LTU, GEU, GTU}},
1373   {"comparison_operator", false, false, {EQ, NE,
1374                                          LE, LT, GE, GT,
1375                                          LEU, LTU, GEU, GTU,
1376                                          UNORDERED, ORDERED,
1377                                          UNEQ, UNGE, UNGT,
1378                                          UNLE, UNLT, LTGT}}
1379 };
1380 #define NUM_KNOWN_STD_PREDS ARRAY_SIZE (std_preds)
1381
1382 /* Initialize the table of predicate definitions, starting with
1383    the information we have on generic predicates.  */
1384
1385 static void
1386 init_predicate_table (void)
1387 {
1388   size_t i, j;
1389   struct pred_data *pred;
1390
1391   predicate_table = htab_create_alloc (37, hash_struct_pred_data,
1392                                        eq_struct_pred_data, 0,
1393                                        xcalloc, free);
1394
1395   for (i = 0; i < NUM_KNOWN_STD_PREDS; i++)
1396     {
1397       pred = XCNEW (struct pred_data);
1398       pred->name = std_preds[i].name;
1399       pred->special = std_preds[i].special;
1400
1401       for (j = 0; std_preds[i].codes[j] != 0; j++)
1402         add_predicate_code (pred, std_preds[i].codes[j]);
1403
1404       if (std_preds[i].allows_const_p)
1405         for (j = 0; j < NUM_RTX_CODE; j++)
1406           if (GET_RTX_CLASS (j) == RTX_CONST_OBJ)
1407             add_predicate_code (pred, (enum rtx_code) j);
1408
1409       add_predicate (pred);
1410     }
1411 }
1412 \f
1413 /* These functions allow linkage with print-rtl.c.  Also, some generators
1414    like to annotate their output with insn names.  */
1415
1416 /* Holds an array of names indexed by insn_code_number.  */
1417 static char **insn_name_ptr = 0;
1418 static int insn_name_ptr_size = 0;
1419
1420 const char *
1421 get_insn_name (int code)
1422 {
1423   if (code < insn_name_ptr_size)
1424     return insn_name_ptr[code];
1425   else
1426     return NULL;
1427 }
1428
1429 static void
1430 record_insn_name (int code, const char *name)
1431 {
1432   static const char *last_real_name = "insn";
1433   static int last_real_code = 0;
1434   char *new_name;
1435
1436   if (insn_name_ptr_size <= code)
1437     {
1438       int new_size;
1439       new_size = (insn_name_ptr_size ? insn_name_ptr_size * 2 : 512);
1440       insn_name_ptr = XRESIZEVEC (char *, insn_name_ptr, new_size);
1441       memset (insn_name_ptr + insn_name_ptr_size, 0,
1442               sizeof(char *) * (new_size - insn_name_ptr_size));
1443       insn_name_ptr_size = new_size;
1444     }
1445
1446   if (!name || name[0] == '\0')
1447     {
1448       new_name = XNEWVAR (char, strlen (last_real_name) + 10);
1449       sprintf (new_name, "%s+%d", last_real_name, code - last_real_code);
1450     }
1451   else
1452     {
1453       last_real_name = new_name = xstrdup (name);
1454       last_real_code = code;
1455     }
1456
1457   insn_name_ptr[code] = new_name;
1458 }