gcc/genconfig.c

   1 /* Generate from machine description:
   2    - some #define configuration flags.
   3    Copyright (C) 1987-2015 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 static void gen_insn (rtx);
  55 static void gen_expand (rtx);
  56 static void gen_split (rtx);
  57 static void gen_peephole (rtx);
  58 static void gen_peephole2 (rtx);
  59
  60 /* RECOG_P will be nonzero if this pattern was seen in a context where it will
  61    be used to recognize, rather than just generate an insn.
  62
  63    NON_PC_SET_SRC will be nonzero if this pattern was seen in a SET_SRC
  64    of a SET whose destination is not (pc).  */
  65
  66 static void
  67 walk_insn_part (rtx part, int recog_p, int non_pc_set_src)
  68 {
  69   int i, j;
  70   RTX_CODE code;
  71   const char *format_ptr;
  72
  73   if (part == 0)
  74     return;
  75
  76   code = GET_CODE (part);
  77   switch (code)
  78     {
  79     case CLOBBER:
  80       clobbers_seen_this_insn++;
  81       break;
  82
  83     case MATCH_OPERAND:
  84       if (XINT (part, 0) > max_recog_operands)
  85         max_recog_operands = XINT (part, 0);
  86       return;
  87
  88     case MATCH_OP_DUP:
  89     case MATCH_PAR_DUP:
  90       ++dup_operands_seen_this_insn;
  91     case MATCH_SCRATCH:
  92     case MATCH_PARALLEL:
  93     case MATCH_OPERATOR:
  94       if (XINT (part, 0) > max_recog_operands)
  95         max_recog_operands = XINT (part, 0);
  96       /* Now scan the rtl's in the vector inside the MATCH_OPERATOR or
  97          MATCH_PARALLEL.  */
  98       break;
  99
 100     case LABEL_REF:
 101       if (GET_CODE (LABEL_REF_LABEL (part)) == MATCH_OPERAND
 102           || GET_CODE (LABEL_REF_LABEL (part)) == MATCH_DUP)
 103         break;
 104       return;
 105
 106     case MATCH_DUP:
 107       ++dup_operands_seen_this_insn;
 108       if (XINT (part, 0) > max_recog_operands)
 109         max_recog_operands = XINT (part, 0);
 110       return;
 111
 112     case CC0:
 113       if (recog_p)
 114         have_cc0_flag = 1;
 115       return;
 116
 117     case LO_SUM:
 118       if (recog_p)
 119         have_lo_sum_flag = 1;
 120       return;
 121
 122     case ROTATE:
 123       if (recog_p)
 124         have_rotate_flag = 1;
 125       return;
 126
 127     case ROTATERT:
 128       if (recog_p)
 129         have_rotatert_flag = 1;
 130       return;
 131
 132     case SET:
 133       walk_insn_part (SET_DEST (part), 0, recog_p);
 134       walk_insn_part (SET_SRC (part), recog_p,
 135                       GET_CODE (SET_DEST (part)) != PC);
 136       return;
 137
 138     case IF_THEN_ELSE:
 139       /* Only consider this machine as having a conditional move if the
 140          two arms of the IF_THEN_ELSE are both MATCH_OPERAND.  Otherwise,
 141          we have some specific IF_THEN_ELSE construct (like the doz
 142          instruction on the RS/6000) that can't be used in the general
 143          context we want it for.  */
 144
 145       if (recog_p && non_pc_set_src
 146           && GET_CODE (XEXP (part, 1)) == MATCH_OPERAND
 147           && GET_CODE (XEXP (part, 2)) == MATCH_OPERAND)
 148         have_cmove_flag = 1;
 149       break;
 150
 151     case COND_EXEC:
 152       if (recog_p)
 153         have_cond_exec_flag = 1;
 154       break;
 155
 156     case REG: case CONST_INT: case SYMBOL_REF:
 157     case PC:
 158       return;
 159
 160     default:
 161       break;
 162     }
 163
 164   format_ptr = GET_RTX_FORMAT (GET_CODE (part));
 165
 166   for (i = 0; i < GET_RTX_LENGTH (GET_CODE (part)); i++)
 167     switch (*format_ptr++)
 168       {
 169       case 'e':
 170       case 'u':
 171         walk_insn_part (XEXP (part, i), recog_p, non_pc_set_src);
 172         break;
 173       case 'E':
 174         if (XVEC (part, i) != NULL)
 175           for (j = 0; j < XVECLEN (part, i); j++)
 176             walk_insn_part (XVECEXP (part, i, j), recog_p, non_pc_set_src);
 177         break;
 178       }
 179 }
 180
 181 static void
 182 gen_insn (rtx insn)
 183 {
 184   int i;
 185
 186   /* Walk the insn pattern to gather the #define's status.  */
 187   clobbers_seen_this_insn = 0;
 188   dup_operands_seen_this_insn = 0;
 189   if (XVEC (insn, 1) != 0)
 190     for (i = 0; i < XVECLEN (insn, 1); i++)
 191       walk_insn_part (XVECEXP (insn, 1, i), 1, 0);
 192
 193   if (clobbers_seen_this_insn > max_clobbers_per_insn)
 194     max_clobbers_per_insn = clobbers_seen_this_insn;
 195   if (dup_operands_seen_this_insn > max_dup_operands)
 196     max_dup_operands = dup_operands_seen_this_insn;
 197 }
 198
 199 /* Similar but scan a define_expand.  */
 200
 201 static void
 202 gen_expand (rtx insn)
 203 {
 204   int i;
 205
 206   /* Walk the insn pattern to gather the #define's status.  */
 207
 208   /* Note that we don't bother recording the number of MATCH_DUPs
 209      that occur in a gen_expand, because only reload cares about that.  */
 210   if (XVEC (insn, 1) != 0)
 211     for (i = 0; i < XVECLEN (insn, 1); i++)
 212       {
 213         /* Compute the maximum SETs and CLOBBERS
 214            in any one of the sub-insns;
 215            don't sum across all of them.  */
 216         clobbers_seen_this_insn = 0;
 217
 218         walk_insn_part (XVECEXP (insn, 1, i), 0, 0);
 219
 220         if (clobbers_seen_this_insn > max_clobbers_per_insn)
 221           max_clobbers_per_insn = clobbers_seen_this_insn;
 222       }
 223 }
 224
 225 /* Similar but scan a define_split.  */
 226
 227 static void
 228 gen_split (rtx split)
 229 {
 230   int i;
 231
 232   /* Look through the patterns that are matched
 233      to compute the maximum operand number.  */
 234   for (i = 0; i < XVECLEN (split, 0); i++)
 235     walk_insn_part (XVECEXP (split, 0, i), 1, 0);
 236   /* Look at the number of insns this insn could split into.  */
 237   if (XVECLEN (split, 2) > max_insns_per_split)
 238     max_insns_per_split = XVECLEN (split, 2);
 239 }
 240
 241 static void
 242 gen_peephole (rtx peep)
 243 {
 244   int i;
 245
 246   /* Look through the patterns that are matched
 247      to compute the maximum operand number.  */
 248   for (i = 0; i < XVECLEN (peep, 0); i++)
 249     walk_insn_part (XVECEXP (peep, 0, i), 1, 0);
 250 }
 251
 252 static void
 253 gen_peephole2 (rtx peep)
 254 {
 255   int i, n;
 256
 257   /* Look through the patterns that are matched
 258      to compute the maximum operand number.  */
 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   rtx desc;
 275
 276   progname = "genconfig";
 277
 278   if (!init_rtx_reader_args (argc, argv))
 279     return (FATAL_EXIT_CODE);
 280
 281   puts ("/* Generated automatically by the program `genconfig'");
 282   puts ("   from the machine description file `md'.  */\n");
 283   puts ("#ifndef GCC_INSN_CONFIG_H");
 284   puts ("#define GCC_INSN_CONFIG_H\n");
 285
 286   /* Allow at least 30 operands for the sake of asm constructs.  */
 287   /* ??? We *really* ought to reorganize things such that there
 288      is no fixed upper bound.  */
 289   max_recog_operands = 29;  /* We will add 1 later.  */
 290   max_dup_operands = 1;
 291
 292   /* Read the machine description.  */
 293
 294   while (1)
 295     {
 296       int line_no, insn_code_number = 0;
 297
 298       desc = read_md_rtx (&line_no, &insn_code_number);
 299       if (desc == NULL)
 300         break;
 301
 302       switch (GET_CODE (desc))
 303         {
 304           case DEFINE_INSN:
 305             gen_insn (desc);
 306             break;
 307
 308           case DEFINE_EXPAND:
 309             gen_expand (desc);
 310             break;
 311
 312           case DEFINE_SPLIT:
 313             gen_split (desc);
 314             break;
 315
 316           case DEFINE_PEEPHOLE2:
 317             have_peephole2_flag = 1;
 318             gen_peephole2 (desc);
 319             break;
 320
 321           case DEFINE_PEEPHOLE:
 322             have_peephole_flag = 1;
 323             gen_peephole (desc);
 324             break;
 325
 326           default:
 327             break;
 328         }
 329     }
 330
 331   printf ("#define MAX_RECOG_OPERANDS %d\n", max_recog_operands + 1);
 332   printf ("#define MAX_DUP_OPERANDS %d\n", max_dup_operands);
 333
 334   /* This is conditionally defined, in case the user writes code which emits
 335      more splits than we can readily see (and knows s/he does it).  */
 336   printf ("#ifndef MAX_INSNS_PER_SPLIT\n");
 337   printf ("#define MAX_INSNS_PER_SPLIT %d\n", max_insns_per_split);
 338   printf ("#endif\n");
 339
 340   if (have_cc0_flag)
 341     {
 342       printf ("#define HAVE_cc0 1\n");
 343       printf ("#define CC0_P(X) ((X) == cc0_rtx)\n");
 344     }
 345   else
 346     {
 347       /* We output CC0_P this way to make sure that X is declared
 348          somewhere.  */
 349       printf ("#define HAVE_cc0 0\n");
 350       printf ("#define CC0_P(X) ((X) ? 0 : 0)\n");
 351     }
 352
 353   if (have_cmove_flag)
 354     printf ("#define HAVE_conditional_move 1\n");
 355   else
 356     printf ("#define HAVE_conditional_move 0\n");
 357
 358   if (have_cond_exec_flag)
 359     printf ("#define HAVE_conditional_execution 1\n");
 360
 361   if (have_lo_sum_flag)
 362     printf ("#define HAVE_lo_sum 1\n");
 363   else
 364     printf ("#define HAVE_lo_sum 0\n");
 365
 366   if (have_rotate_flag)
 367     printf ("#define HAVE_rotate 1\n");
 368
 369   if (have_rotatert_flag)
 370     printf ("#define HAVE_rotatert 1\n");
 371
 372   if (have_peephole_flag)
 373     printf ("#define HAVE_peephole 1\n");
 374   else
 375     printf ("#define HAVE_peephole 0\n");
 376
 377   if (have_peephole2_flag)
 378     {
 379       printf ("#define HAVE_peephole2 1\n");
 380       printf ("#define MAX_INSNS_PER_PEEP2 %d\n", max_insns_per_peep2);
 381     }
 382
 383   puts ("\n#endif /* GCC_INSN_CONFIG_H */");
 384
 385   if (ferror (stdout) || fflush (stdout) || fclose (stdout))
 386     return FATAL_EXIT_CODE;
 387
 388   return SUCCESS_EXIT_CODE;
 389 }