gcc/genconfig.c

   1 /* Generate from machine description:
   2    - some #define configuration flags.
   3    Copyright (C) 1987-2016 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 3, 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 COPYING3.  If not see
  19 <http://www.gnu.org/licenses/>.  */
  20
  21
  22 #include "bconfig.h"
  23 #include "system.h"
  24 #include "coretypes.h"
  25 #include "tm.h"
  26 #include "rtl.h"
  27 #include "errors.h"
  28 #include "gensupport.h"
  29
  30
  31 /* flags to determine output of machine description dependent #define's.  */
  32 static int max_recog_operands;  /* Largest operand number seen.  */
  33 static int max_dup_operands;    /* Largest number of match_dup in any insn.  */
  34 static int max_clobbers_per_insn;
  35 static int have_cc0_flag;
  36 static int have_cmove_flag;
  37 static int have_cond_exec_flag;
  38 static int have_lo_sum_flag;
  39 static int have_rotate_flag;
  40 static int have_rotatert_flag;
  41 static int have_peephole_flag;
  42 static int have_peephole2_flag;
  43
  44 /* Maximum number of insns seen in a split.  */
  45 static int max_insns_per_split = 1;
  46
  47 /* Maximum number of input insns for peephole2.  */
  48 static int max_insns_per_peep2;
  49
  50 static int clobbers_seen_this_insn;
  51 static int dup_operands_seen_this_insn;
  52
  53 static void walk_insn_part (rtx, int, int);
  54
  55 /* RECOG_P will be nonzero if this pattern was seen in a context where it will
  56    be used to recognize, rather than just generate an insn.
  57
  58    NON_PC_SET_SRC will be nonzero if this pattern was seen in a SET_SRC
  59    of a SET whose destination is not (pc).  */
  60
  61 static void
  62 walk_insn_part (rtx part, int recog_p, int non_pc_set_src)
  63 {
  64   int i, j;
  65   RTX_CODE code;
  66   const char *format_ptr;
  67
  68   if (part == 0)
  69     return;
  70
  71   code = GET_CODE (part);
  72   switch (code)
  73     {
  74     case CLOBBER:
  75       clobbers_seen_this_insn++;
  76       break;
  77
  78     case MATCH_OPERAND:
  79       if (XINT (part, 0) > max_recog_operands)
  80         max_recog_operands = XINT (part, 0);
  81       return;
  82
  83     case MATCH_OP_DUP:
  84     case MATCH_PAR_DUP:
  85       ++dup_operands_seen_this_insn;
  86     case MATCH_SCRATCH:
  87     case MATCH_PARALLEL:
  88     case MATCH_OPERATOR:
  89       if (XINT (part, 0) > max_recog_operands)
  90         max_recog_operands = XINT (part, 0);
  91       /* Now scan the rtl's in the vector inside the MATCH_OPERATOR or
  92          MATCH_PARALLEL.  */
  93       break;
  94
  95     case LABEL_REF:
  96       if (GET_CODE (LABEL_REF_LABEL (part)) == MATCH_OPERAND
  97           || GET_CODE (LABEL_REF_LABEL (part)) == MATCH_DUP)
  98         break;
  99       return;
 100
 101     case MATCH_DUP:
 102       ++dup_operands_seen_this_insn;
 103       if (XINT (part, 0) > max_recog_operands)
 104         max_recog_operands = XINT (part, 0);
 105       return;
 106
 107     case CC0:
 108       if (recog_p)
 109         have_cc0_flag = 1;
 110       return;
 111
 112     case LO_SUM:
 113       if (recog_p)
 114         have_lo_sum_flag = 1;
 115       return;
 116
 117     case ROTATE:
 118       if (recog_p)
 119         have_rotate_flag = 1;
 120       return;
 121
 122     case ROTATERT:
 123       if (recog_p)
 124         have_rotatert_flag = 1;
 125       return;
 126
 127     case SET:
 128       walk_insn_part (SET_DEST (part), 0, recog_p);
 129       walk_insn_part (SET_SRC (part), recog_p,
 130                       GET_CODE (SET_DEST (part)) != PC);
 131       return;
 132
 133     case IF_THEN_ELSE:
 134       /* Only consider this machine as having a conditional move if the
 135          two arms of the IF_THEN_ELSE are both MATCH_OPERAND.  Otherwise,
 136          we have some specific IF_THEN_ELSE construct (like the doz
 137          instruction on the RS/6000) that can't be used in the general
 138          context we want it for.  */
 139
 140       if (recog_p && non_pc_set_src
 141           && GET_CODE (XEXP (part, 1)) == MATCH_OPERAND
 142           && GET_CODE (XEXP (part, 2)) == MATCH_OPERAND)
 143         have_cmove_flag = 1;
 144       break;
 145
 146     case COND_EXEC:
 147       if (recog_p)
 148         have_cond_exec_flag = 1;
 149       break;
 150
 151     case REG: case CONST_INT: case SYMBOL_REF:
 152     case PC:
 153       return;
 154
 155     default:
 156       break;
 157     }
 158
 159   format_ptr = GET_RTX_FORMAT (GET_CODE (part));
 160
 161   for (i = 0; i < GET_RTX_LENGTH (GET_CODE (part)); i++)
 162     switch (*format_ptr++)
 163       {
 164       case 'e':
 165       case 'u':
 166         walk_insn_part (XEXP (part, i), recog_p, non_pc_set_src);
 167         break;
 168       case 'E':
 169         if (XVEC (part, i) != NULL)
 170           for (j = 0; j < XVECLEN (part, i); j++)
 171             walk_insn_part (XVECEXP (part, i, j), recog_p, non_pc_set_src);
 172         break;
 173       }
 174 }
 175
 176 static void
 177 gen_insn (md_rtx_info *info)
 178 {
 179   int i;
 180
 181   /* Walk the insn pattern to gather the #define's status.  */
 182   rtx insn = info->def;
 183   clobbers_seen_this_insn = 0;
 184   dup_operands_seen_this_insn = 0;
 185   if (XVEC (insn, 1) != 0)
 186     for (i = 0; i < XVECLEN (insn, 1); i++)
 187       walk_insn_part (XVECEXP (insn, 1, i), 1, 0);
 188
 189   if (clobbers_seen_this_insn > max_clobbers_per_insn)
 190     max_clobbers_per_insn = clobbers_seen_this_insn;
 191   if (dup_operands_seen_this_insn > max_dup_operands)
 192     max_dup_operands = dup_operands_seen_this_insn;
 193 }
 194
 195 /* Similar but scan a define_expand.  */
 196
 197 static void
 198 gen_expand (md_rtx_info *info)
 199 {
 200   int i;
 201
 202   /* Walk the insn pattern to gather the #define's status.  */
 203
 204   /* Note that we don't bother recording the number of MATCH_DUPs
 205      that occur in a gen_expand, because only reload cares about that.  */
 206   rtx insn = info->def;
 207   if (XVEC (insn, 1) != 0)
 208     for (i = 0; i < XVECLEN (insn, 1); i++)
 209       {
 210         /* Compute the maximum SETs and CLOBBERS
 211            in any one of the sub-insns;
 212            don't sum across all of them.  */
 213         clobbers_seen_this_insn = 0;
 214
 215         walk_insn_part (XVECEXP (insn, 1, i), 0, 0);
 216
 217         if (clobbers_seen_this_insn > max_clobbers_per_insn)
 218           max_clobbers_per_insn = clobbers_seen_this_insn;
 219       }
 220 }
 221
 222 /* Similar but scan a define_split.  */
 223
 224 static void
 225 gen_split (md_rtx_info *info)
 226 {
 227   int i;
 228
 229   /* Look through the patterns that are matched
 230      to compute the maximum operand number.  */
 231   rtx split = info->def;
 232   for (i = 0; i < XVECLEN (split, 0); i++)
 233     walk_insn_part (XVECEXP (split, 0, i), 1, 0);
 234   /* Look at the number of insns this insn could split into.  */
 235   if (XVECLEN (split, 2) > max_insns_per_split)
 236     max_insns_per_split = XVECLEN (split, 2);
 237 }
 238
 239 static void
 240 gen_peephole (md_rtx_info *info)
 241 {
 242   int i;
 243
 244   /* Look through the patterns that are matched
 245      to compute the maximum operand number.  */
 246   rtx peep = info->def;
 247   for (i = 0; i < XVECLEN (peep, 0); i++)
 248     walk_insn_part (XVECEXP (peep, 0, i), 1, 0);
 249 }
 250
 251 static void
 252 gen_peephole2 (md_rtx_info *info)
 253 {
 254   int i, n;
 255
 256   /* Look through the patterns that are matched
 257      to compute the maximum operand number.  */
 258   rtx peep = info->def;
 259   for (i = XVECLEN (peep, 0) - 1; i >= 0; --i)
 260     walk_insn_part (XVECEXP (peep, 0, i), 1, 0);
 261
 262   /* Look at the number of insns this insn can be matched from.  */
 263   for (i = XVECLEN (peep, 0) - 1, n = 0; i >= 0; --i)
 264     if (GET_CODE (XVECEXP (peep, 0, i)) != MATCH_DUP
 265         && GET_CODE (XVECEXP (peep, 0, i)) != MATCH_SCRATCH)
 266       n++;
 267   if (n > max_insns_per_peep2)
 268     max_insns_per_peep2 = n;
 269 }
 270
 271 int
 272 main (int argc, char **argv)
 273 {
 274   progname = "genconfig";
 275
 276   if (!init_rtx_reader_args (argc, argv))
 277     return (FATAL_EXIT_CODE);
 278
 279   puts ("/* Generated automatically by the program `genconfig'");
 280   puts ("   from the machine description file `md'.  */\n");
 281   puts ("#ifndef GCC_INSN_CONFIG_H");
 282   puts ("#define GCC_INSN_CONFIG_H\n");
 283
 284   /* Allow at least 30 operands for the sake of asm constructs.  */
 285   /* ??? We *really* ought to reorganize things such that there
 286      is no fixed upper bound.  */
 287   max_recog_operands = 29;  /* We will add 1 later.  */
 288   max_dup_operands = 1;
 289
 290   /* Read the machine description.  */
 291
 292   md_rtx_info info;
 293   while (read_md_rtx (&info))
 294     switch (GET_CODE (info.def))
 295       {
 296       case DEFINE_INSN:
 297         gen_insn (&info);
 298         break;
 299
 300       case DEFINE_EXPAND:
 301         gen_expand (&info);
 302         break;
 303
 304       case DEFINE_SPLIT:
 305         gen_split (&info);
 306         break;
 307
 308       case DEFINE_PEEPHOLE2:
 309         have_peephole2_flag = 1;
 310         gen_peephole2 (&info);
 311         break;
 312
 313       case DEFINE_PEEPHOLE:
 314         have_peephole_flag = 1;
 315         gen_peephole (&info);
 316         break;
 317
 318       default:
 319         break;
 320       }
 321
 322   printf ("#define MAX_RECOG_OPERANDS %d\n", max_recog_operands + 1);
 323   printf ("#define MAX_DUP_OPERANDS %d\n", max_dup_operands);
 324
 325   /* This is conditionally defined, in case the user writes code which emits
 326      more splits than we can readily see (and knows s/he does it).  */
 327   printf ("#ifndef MAX_INSNS_PER_SPLIT\n");
 328   printf ("#define MAX_INSNS_PER_SPLIT %d\n", max_insns_per_split);
 329   printf ("#endif\n");
 330
 331   if (have_cc0_flag)
 332     {
 333       printf ("#define HAVE_cc0 1\n");
 334       printf ("#define CC0_P(X) ((X) == cc0_rtx)\n");
 335     }
 336   else
 337     {
 338       /* We output CC0_P this way to make sure that X is declared
 339          somewhere.  */
 340       printf ("#define HAVE_cc0 0\n");
 341       printf ("#define CC0_P(X) ((X) ? 0 : 0)\n");
 342     }
 343
 344   if (have_cmove_flag)
 345     printf ("#define HAVE_conditional_move 1\n");
 346   else
 347     printf ("#define HAVE_conditional_move 0\n");
 348
 349   if (have_cond_exec_flag)
 350     printf ("#define HAVE_conditional_execution 1\n");
 351   else
 352     printf ("#define HAVE_conditional_execution 0\n");
 353
 354   if (have_lo_sum_flag)
 355     printf ("#define HAVE_lo_sum 1\n");
 356   else
 357     printf ("#define HAVE_lo_sum 0\n");
 358
 359   if (have_rotate_flag)
 360     printf ("#define HAVE_rotate 1\n");
 361
 362   if (have_rotatert_flag)
 363     printf ("#define HAVE_rotatert 1\n");
 364
 365   if (have_peephole_flag)
 366     printf ("#define HAVE_peephole 1\n");
 367   else
 368     printf ("#define HAVE_peephole 0\n");
 369
 370   if (have_peephole2_flag)
 371     {
 372       printf ("#define HAVE_peephole2 1\n");
 373       printf ("#define MAX_INSNS_PER_PEEP2 %d\n", max_insns_per_peep2);
 374     }
 375   else
 376     {
 377       printf ("#define HAVE_peephole2 0\n");
 378       printf ("#define MAX_INSNS_PER_PEEP2 0\n");
 379     }
 380
 381   puts ("\n#endif /* GCC_INSN_CONFIG_H */");
 382
 383   if (ferror (stdout) || fflush (stdout) || fclose (stdout))
 384     return FATAL_EXIT_CODE;
 385
 386   return SUCCESS_EXIT_CODE;
 387 }