gcc/genflags.c

   1 /* Generate from machine description:
   2    - some flags HAVE_... saying which simple standard instructions are
   3    available for this machine.
   4    Copyright (C) 1987, 1991, 1995, 1998,
   5    1999, 2000, 2003, 2004 Free Software Foundation, Inc.
   6
   7 This file is part of GCC.
   8
   9 GCC is free software; you can redistribute it and/or modify it under
  10 the terms of the GNU General Public License as published by the Free
  11 Software Foundation; either version 2, or (at your option) any later
  12 version.
  13
  14 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
  15 WARRANTY; without even the implied warranty of MERCHANTABILITY or
  16 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  17 for more details.
  18
  19 You should have received a copy of the GNU General Public License
  20 along with GCC; see the file COPYING.  If not, write to the Free
  21 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
  22 02110-1301, USA.  */
  23
  24
  25 #include "bconfig.h"
  26 #include "system.h"
  27 #include "coretypes.h"
  28 #include "tm.h"
  29 #include "rtl.h"
  30 #include "obstack.h"
  31 #include "errors.h"
  32 #include "gensupport.h"
  33
  34 /* Obstack to remember insns with.  */
  35 static struct obstack obstack;
  36
  37 /* Max size of names encountered.  */
  38 static int max_id_len;
  39
  40 /* Max operand encountered in a scan over some insn.  */
  41 static int max_opno;
  42
  43 static void max_operand_1 (rtx);
  44 static int num_operands (rtx);
  45 static void gen_proto (rtx);
  46 static void gen_macro (const char *, int, int);
  47 static void gen_insn (rtx);
  48
  49 /* Count the number of match_operand's found.  */
  50
  51 static void
  52 max_operand_1 (rtx x)
  53 {
  54   RTX_CODE code;
  55   int i;
  56   int len;
  57   const char *fmt;
  58
  59   if (x == 0)
  60     return;
  61
  62   code = GET_CODE (x);
  63
  64   if (code == MATCH_OPERAND || code == MATCH_OPERATOR
  65       || code == MATCH_PARALLEL)
  66     max_opno = MAX (max_opno, XINT (x, 0));
  67
  68   fmt = GET_RTX_FORMAT (code);
  69   len = GET_RTX_LENGTH (code);
  70   for (i = 0; i < len; i++)
  71     {
  72       if (fmt[i] == 'e' || fmt[i] == 'u')
  73         max_operand_1 (XEXP (x, i));
  74       else if (fmt[i] == 'E')
  75         {
  76           int j;
  77           for (j = 0; j < XVECLEN (x, i); j++)
  78             max_operand_1 (XVECEXP (x, i, j));
  79         }
  80     }
  81 }
  82
  83 static int
  84 num_operands (rtx insn)
  85 {
  86   int len = XVECLEN (insn, 1);
  87   int i;
  88
  89   max_opno = -1;
  90
  91   for (i = 0; i < len; i++)
  92     max_operand_1 (XVECEXP (insn, 1, i));
  93
  94   return max_opno + 1;
  95 }
  96
  97 /* Print out a wrapper macro for a function which corrects the number
  98    of arguments it takes.  Any missing arguments are assumed to be at
  99    the end.  */
 100 static void
 101 gen_macro (const char *name, int real, int expect)
 102 {
 103   int i;
 104
 105   gcc_assert (real <= expect);
 106   gcc_assert (real);
 107
 108   /* #define GEN_CALL(A, B, C, D) gen_call((A), (B)) */
 109   fputs ("#define GEN_", stdout);
 110   for (i = 0; name[i]; i++)
 111     putchar (TOUPPER (name[i]));
 112
 113   putchar('(');
 114   for (i = 0; i < expect - 1; i++)
 115     printf ("%c, ", i + 'A');
 116   printf ("%c) gen_%s (", i + 'A', name);
 117
 118   for (i = 0; i < real - 1; i++)
 119     printf ("(%c), ", i + 'A');
 120   printf ("(%c))\n", i + 'A');
 121 }
 122
 123 /* Print out prototype information for a generator function.  If the
 124    insn pattern has been elided, print out a dummy generator that
 125    does nothing.  */
 126
 127 static void
 128 gen_proto (rtx insn)
 129 {
 130   int num = num_operands (insn);
 131   int i;
 132   const char *name = XSTR (insn, 0);
 133   int truth = maybe_eval_c_test (XSTR (insn, 2));
 134
 135   /* Many md files don't refer to the last two operands passed to the
 136      call patterns.  This means their generator functions will be two
 137      arguments too short.  Instead of changing every md file to touch
 138      those operands, we wrap the prototypes in macros that take the
 139      correct number of arguments.  */
 140   if (name[0] == 'c' || name[0] == 's')
 141     {
 142       if (!strcmp (name, "call")
 143           || !strcmp (name, "call_pop")
 144           || !strcmp (name, "sibcall")
 145           || !strcmp (name, "sibcall_pop"))
 146         gen_macro (name, num, 4);
 147       else if (!strcmp (name, "call_value")
 148                || !strcmp (name, "call_value_pop")
 149                || !strcmp (name, "sibcall_value")
 150                || !strcmp (name, "sibcall_value_pop"))
 151         gen_macro (name, num, 5);
 152     }
 153
 154   if (truth != 0)
 155     printf ("extern rtx        gen_%-*s (", max_id_len, name);
 156   else
 157     printf ("static inline rtx gen_%-*s (", max_id_len, name);
 158
 159   if (num == 0)
 160     fputs ("void", stdout);
 161   else
 162     {
 163       for (i = 1; i < num; i++)
 164         fputs ("rtx, ", stdout);
 165
 166       fputs ("rtx", stdout);
 167     }
 168
 169   puts (");");
 170
 171   /* Some back ends want to take the address of generator functions,
 172      so we cannot simply use #define for these dummy definitions.  */
 173   if (truth == 0)
 174     {
 175       printf ("static inline rtx\ngen_%s", name);
 176       if (num > 0)
 177         {
 178           putchar ('(');
 179           for (i = 0; i < num-1; i++)
 180             printf ("rtx ARG_UNUSED (%c), ", 'a' + i);
 181           printf ("rtx ARG_UNUSED (%c))\n", 'a' + i);
 182         }
 183       else
 184         puts ("(void)");
 185       puts ("{\n  return 0;\n}");
 186     }
 187
 188 }
 189
 190 static void
 191 gen_insn (rtx insn)
 192 {
 193   const char *name = XSTR (insn, 0);
 194   const char *p;
 195   int len;
 196   int truth = maybe_eval_c_test (XSTR (insn, 2));
 197
 198   /* Don't mention instructions whose names are the null string
 199      or begin with '*'.  They are in the machine description just
 200      to be recognized.  */
 201   if (name[0] == 0 || name[0] == '*')
 202     return;
 203
 204   len = strlen (name);
 205
 206   if (len > max_id_len)
 207     max_id_len = len;
 208
 209   if (truth == 0)
 210     /* Emit nothing.  */;
 211   else if (truth == 1)
 212     printf ("#define HAVE_%s 1\n", name);
 213   else
 214     {
 215       /* Write the macro definition, putting \'s at the end of each line,
 216          if more than one.  */
 217       printf ("#define HAVE_%s (", name);
 218       for (p = XSTR (insn, 2); *p; p++)
 219         {
 220           if (IS_VSPACE (*p))
 221             fputs (" \\\n", stdout);
 222           else
 223             putchar (*p);
 224         }
 225       fputs (")\n", stdout);
 226     }
 227
 228   obstack_grow (&obstack, &insn, sizeof (rtx));
 229 }
 230
 231 int
 232 main (int argc, char **argv)
 233 {
 234   rtx desc;
 235   rtx dummy;
 236   rtx *insns;
 237   rtx *insn_ptr;
 238
 239   progname = "genflags";
 240   obstack_init (&obstack);
 241
 242   /* We need to see all the possibilities.  Elided insns may have
 243      direct calls to their generators in C code.  */
 244   insn_elision = 0;
 245
 246   if (init_md_reader_args (argc, argv) != SUCCESS_EXIT_CODE)
 247     return (FATAL_EXIT_CODE);
 248
 249   puts ("/* Generated automatically by the program `genflags'");
 250   puts ("   from the machine description file `md'.  */\n");
 251   puts ("#ifndef GCC_INSN_FLAGS_H");
 252   puts ("#define GCC_INSN_FLAGS_H\n");
 253
 254   /* Read the machine description.  */
 255
 256   while (1)
 257     {
 258       int line_no, insn_code_number = 0;
 259
 260       desc = read_md_rtx (&line_no, &insn_code_number);
 261       if (desc == NULL)
 262         break;
 263       if (GET_CODE (desc) == DEFINE_INSN || GET_CODE (desc) == DEFINE_EXPAND)
 264         gen_insn (desc);
 265     }
 266
 267   /* Print out the prototypes now.  */
 268   dummy = (rtx) 0;
 269   obstack_grow (&obstack, &dummy, sizeof (rtx));
 270   insns = XOBFINISH (&obstack, rtx *);
 271
 272   for (insn_ptr = insns; *insn_ptr; insn_ptr++)
 273     gen_proto (*insn_ptr);
 274
 275   puts("\n#endif /* GCC_INSN_FLAGS_H */");
 276
 277   if (ferror (stdout) || fflush (stdout) || fclose (stdout))
 278     return FATAL_EXIT_CODE;
 279
 280   return SUCCESS_EXIT_CODE;
 281 }