gcc/gengenrtl.c

   1 /* Generate code to allocate RTL structures.
   2    Copyright (C) 1997, 1998, 1999, 2000 Free Software Foundation, Inc.
   3
   4 This file is part of GNU CC.
   5
   6 GNU CC is free software; you can redistribute it and/or modify
   7 it under the terms of the GNU General Public License as published by
   8 the Free Software Foundation; either version 2, or (at your option)
   9 any later version.
  10
  11 GNU CC is distributed in the hope that it will be useful,
  12 but WITHOUT ANY WARRANTY; without even the implied warranty of
  13 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  14 GNU General Public License for more details.
  15
  16 You should have received a copy of the GNU General Public License
  17 along with GNU CC; see the file COPYING.  If not, write to
  18 the Free Software Foundation, 59 Temple Place - Suite 330,
  19 Boston, MA 02111-1307, USA.  */
  20
  21
  22 #include "hconfig.h"
  23 #include "system.h"
  24
  25 #define NO_GENRTL_H
  26 #include "rtl.h"
  27 #undef abort
  28
  29 #include "real.h"
  30
  31 /* Calculate the format for CONST_DOUBLE.  This depends on the relative
  32    widths of HOST_WIDE_INT and REAL_VALUE_TYPE.
  33
  34    We need to go out to e0wwwww, since REAL_ARITHMETIC assumes 16-bits
  35    per element in REAL_VALUE_TYPE.
  36
  37    This is duplicated in rtl.c.
  38
  39    A number of places assume that there are always at least two 'w'
  40    slots in a CONST_DOUBLE, so we provide them even if one would suffice.  */
  41
  42 #ifdef REAL_ARITHMETIC
  43 #if MAX_LONG_DOUBLE_TYPE_SIZE == 96
  44 #define REAL_WIDTH      (11*8 + HOST_BITS_PER_WIDE_INT)/HOST_BITS_PER_WIDE_INT
  45 #elif MAX_LONG_DOUBLE_TYPE_SIZE == 128
  46 #define REAL_WIDTH      (19*8 + HOST_BITS_PER_WIDE_INT)/HOST_BITS_PER_WIDE_INT
  47 #elif HOST_FLOAT_FORMAT != TARGET_FLOAT_FORMAT
  48 #define REAL_WIDTH      (7*8 + HOST_BITS_PER_WIDE_INT)/HOST_BITS_PER_WIDE_INT
  49 #endif
  50 #endif /* REAL_ARITHMETIC */
  51
  52 #ifndef REAL_WIDTH
  53 #if HOST_BITS_PER_WIDE_INT*2 >= MAX_LONG_DOUBLE_TYPE_SIZE
  54 #define REAL_WIDTH      2
  55 #elif HOST_BITS_PER_WIDE_INT*3 >= MAX_LONG_DOUBLE_TYPE_SIZE
  56 #define REAL_WIDTH      3
  57 #elif HOST_BITS_PER_WIDE_INT*4 >= MAX_LONG_DOUBLE_TYPE_SIZE
  58 #define REAL_WIDTH      4
  59 #endif
  60 #endif /* REAL_WIDTH */
  61
  62 #if REAL_WIDTH == 1
  63 #define CONST_DOUBLE_FORMAT     "e0ww"
  64 #elif REAL_WIDTH == 2
  65 #define CONST_DOUBLE_FORMAT     "e0ww"
  66 #elif REAL_WIDTH == 3
  67 #define CONST_DOUBLE_FORMAT     "e0www"
  68 #elif REAL_WIDTH == 4
  69 #define CONST_DOUBLE_FORMAT     "e0wwww"
  70 #elif REAL_WIDTH == 5
  71 #define CONST_DOUBLE_FORMAT     "e0wwwww"
  72 #else
  73 #define CONST_DOUBLE_FORMAT     /* nothing - will cause syntax error */
  74 #endif
  75
  76
  77 struct rtx_definition
  78 {
  79   const char *enumname, *name, *format;
  80 };
  81
  82 #define DEF_RTL_EXPR(ENUM, NAME, FORMAT, CLASS) { STRINGIFY(ENUM), NAME, FORMAT },
  83
  84 struct rtx_definition defs[] =
  85 {
  86 #include "rtl.def"              /* rtl expressions are documented here */
  87 };
  88
  89 const char *formats[NUM_RTX_CODE];
  90
  91 static const char *type_from_format     PARAMS ((int));
  92 static const char *accessor_from_format PARAMS ((int));
  93 static int special_format               PARAMS ((const char *));
  94 static int special_rtx                  PARAMS ((int));
  95 static void find_formats                PARAMS ((void));
  96 static void gendecl                     PARAMS ((const char *));
  97 static void genmacro                    PARAMS ((int));
  98 static void gendef                      PARAMS ((const char *));
  99 static void genlegend                   PARAMS ((void));
 100 static void genheader                   PARAMS ((void));
 101 static void gencode                     PARAMS ((void));
 102 \f
 103 /* Decode a format letter into a C type string.  */
 104
 105 static const char *
 106 type_from_format (c)
 107      int c;
 108 {
 109   switch (c)
 110     {
 111     case 'i':
 112       return "int ";
 113
 114     case 'w':
 115       return "HOST_WIDE_INT ";
 116
 117     case 's':
 118       return "const char *";
 119
 120     case 'e':  case 'u':
 121       return "rtx ";
 122
 123     case 'E':
 124       return "rtvec ";
 125     case 'b':
 126       return "struct bitmap_head_def *";  /* bitmap - typedef not available */
 127     case 't':
 128       return "union tree_node *";  /* tree - typedef not available */
 129     default:
 130       abort ();
 131     }
 132 }
 133
 134 /* Decode a format letter into the proper accessor function.  */
 135
 136 static const char *
 137 accessor_from_format (c)
 138      int c;
 139 {
 140   switch (c)
 141     {
 142     case 'i':
 143       return "XINT";
 144
 145     case 'w':
 146       return "XWINT";
 147
 148     case 's':
 149       return "XSTR";
 150
 151     case 'e':  case 'u':
 152       return "XEXP";
 153
 154     case 'E':
 155       return "XVEC";
 156
 157     case 'b':
 158       return "XBITMAP";
 159
 160     case 't':
 161       return "XTREE";
 162
 163     default:
 164       abort ();
 165     }
 166 }
 167
 168 /* Return nonzero if we should ignore FMT, an RTL format, when making
 169    the list of formats we write routines to create.  */
 170
 171 static int
 172 special_format (fmt)
 173      const char *fmt;
 174 {
 175   return (strchr (fmt, '*') != 0
 176           || strchr (fmt, 'V') != 0
 177           || strchr (fmt, 'S') != 0
 178           || strchr (fmt, 'n') != 0);
 179 }
 180
 181 /* Return nonzero if the RTL code given by index IDX is one that we should not
 182    generate a gen_RTX_FOO function foo (because that function is present
 183    elsewhere in the compiler).  */
 184
 185 static int
 186 special_rtx (idx)
 187      int idx;
 188 {
 189   return (strcmp (defs[idx].enumname, "CONST_INT") == 0
 190           || strcmp (defs[idx].enumname, "CONST_DOUBLE") == 0
 191           || strcmp (defs[idx].enumname, "REG") == 0
 192           || strcmp (defs[idx].enumname, "MEM") == 0);
 193 }
 194
 195 /* Place a list of all format specifiers we use into the array FORMAT. */
 196
 197 static void
 198 find_formats ()
 199 {
 200   int i;
 201
 202   for (i = 0; i < NUM_RTX_CODE; i++)
 203     {
 204       const char **f;
 205
 206       if (special_format (defs[i].format))
 207         continue;
 208
 209       for (f = formats; *f; f++)
 210         if (! strcmp (*f, defs[i].format))
 211           break;
 212
 213       if (*f == 0)
 214         *f = defs[i].format;
 215     }
 216 }
 217
 218 /* Write the declarations for the routine to allocate RTL with FORMAT.  */
 219
 220 static void
 221 gendecl (format)
 222      const char *format;
 223 {
 224   const char *p;
 225   int i, pos;
 226
 227   printf ("extern rtx gen_rtx_fmt_%s\tPARAMS ((RTX_CODE, ", format);
 228   printf ("enum machine_mode mode");
 229
 230   /* Write each parameter that is needed and start a new line when the line
 231      would overflow.  */
 232   for (p = format, i = 0, pos = 75; *p != 0; p++)
 233     if (*p != '0')
 234       {
 235         int ourlen = strlen (type_from_format (*p)) + 6 + (i > 9);
 236
 237         printf (",");
 238         if (pos + ourlen > 76)
 239           printf ("\n\t\t\t\t      "), pos = 39;
 240
 241         printf (" %sarg%d", type_from_format (*p), i++);
 242         pos += ourlen;
 243       }
 244
 245   printf ("));\n");
 246 }
 247
 248 /* Generate macros to generate RTL of code IDX using the functions we
 249    write.  */
 250
 251 static void
 252 genmacro (idx)
 253      int idx;
 254 {
 255   const char *p;
 256   int i;
 257
 258   /* We write a macro that defines gen_rtx_RTLCODE to be an equivalent to
 259      gen_rtx_fmt_FORMAT where FORMAT is the RTX_FORMAT of RTLCODE.  */
 260
 261   printf ("#define gen_rtx_%s%s(MODE",
 262            special_rtx (idx) ? "raw_" : "", defs[idx].enumname);
 263
 264   for (p = defs[idx].format, i = 0; *p != 0; p++)
 265     if (*p != '0')
 266       printf (", ARG%d", i++);
 267
 268   printf (") \\\n  gen_rtx_fmt_%s (%s, (MODE)",
 269           defs[idx].format, defs[idx].enumname);
 270
 271   for (p = defs[idx].format, i = 0; *p != 0; p++)
 272     if (*p != '0')
 273       printf (", (ARG%d)", i++);
 274
 275   puts (")");
 276 }
 277
 278 /* Generate the code for the function to generate RTL whose
 279    format is FORMAT.  */
 280
 281 static void
 282 gendef (format)
 283      const char *format;
 284 {
 285   const char *p;
 286   int i, j;
 287
 288   /* Start by writing the definition of the function name and the types
 289      of the arguments.  */
 290
 291   printf ("rtx\ngen_rtx_fmt_%s (code, mode", format);
 292   for (p = format, i = 0; *p != 0; p++)
 293     if (*p != '0')
 294       printf (", arg%d", i++);
 295
 296   puts (")\n     RTX_CODE code;\n     enum machine_mode mode;");
 297   for (p = format, i = 0; *p != 0; p++)
 298     if (*p != '0')
 299       printf ("     %sarg%d;\n", type_from_format (*p), i++);
 300
 301   /* Now write out the body of the function itself, which allocates
 302      the memory and initializes it.  */
 303   puts ("{");
 304   puts ("  rtx rt;");
 305   puts ("  if (ggc_p)");
 306   printf ("    rt = ggc_alloc_rtx (%d);\n", (int) strlen (format));
 307   puts ("  else");
 308   printf ("    rt = obstack_alloc_rtx (%d);\n", (int) strlen (format));
 309
 310   puts ("  memset (rt, 0, sizeof (struct rtx_def) - sizeof (rtunion));\n");
 311   puts ("  PUT_CODE (rt, code);");
 312   puts ("  PUT_MODE (rt, mode);");
 313
 314   for (p = format, i = j = 0; *p ; ++p, ++i)
 315     if (*p != '0')
 316       printf ("  %s (rt, %d) = arg%d;\n", accessor_from_format (*p), i, j++);
 317     else
 318       printf ("  X0EXP (rt, %d) = NULL_RTX;\n", i);
 319
 320   puts ("\n  return rt;\n}\n");
 321 }
 322
 323 /* Generate the documentation header for files we write.  */
 324
 325 static void
 326 genlegend ()
 327 {
 328   puts ("/* Generated automatically by gengenrtl from rtl.def.  */\n");
 329 }
 330
 331 /* Generate the text of the header file we make, genrtl.h.  */
 332
 333 static void
 334 genheader ()
 335 {
 336   int i;
 337   const char **fmt;
 338
 339   for (fmt = formats; *fmt; ++fmt)
 340     gendecl (*fmt);
 341
 342   putchar ('\n');
 343
 344   for (i = 0; i < NUM_RTX_CODE; i++)
 345     if (! special_format (defs[i].format))
 346       genmacro (i);
 347 }
 348
 349 /* Generate the text of the code file we write, genrtl.c.  */
 350
 351 static void
 352 gencode ()
 353 {
 354   const char **fmt;
 355
 356   puts ("#include \"config.h\"");
 357   puts ("#include \"system.h\"");
 358   puts ("#include \"obstack.h\"");
 359   puts ("#include \"rtl.h\"");
 360   puts ("#include \"ggc.h\"\n");
 361   puts ("extern struct obstack *rtl_obstack;\n");
 362   puts ("#define obstack_alloc_rtx(n)                                   \\");
 363   puts ("    ((rtx) obstack_alloc (rtl_obstack,                         \\");
 364   puts ("                         sizeof (struct rtx_def)               \\");
 365   puts ("                         + ((n) - 1) * sizeof (rtunion)))\n");
 366
 367   for (fmt = formats; *fmt != 0; fmt++)
 368     gendef (*fmt);
 369 }
 370
 371 #if defined(USE_C_ALLOCA)
 372 PTR
 373 xmalloc (nbytes)
 374   size_t nbytes;
 375 {
 376   register PTR tmp = (PTR) malloc (nbytes);
 377
 378   if (!tmp)
 379     {
 380       fprintf (stderr, "can't allocate %d bytes (out of virtual memory)\n",
 381                nbytes);
 382       exit (FATAL_EXIT_CODE);
 383     }
 384
 385   return tmp;
 386 }
 387 #endif /* USE_C_ALLOCA */
 388
 389 /* This is the main program.  We accept only one argument, "-h", which
 390    says we are writing the genrtl.h file.  Otherwise we are writing the
 391    genrtl.c file.  */
 392 extern int main PARAMS ((int, char **));
 393
 394 int
 395 main (argc, argv)
 396      int argc;
 397      char **argv;
 398 {
 399   find_formats ();
 400   genlegend ();
 401
 402   if (argc == 2 && argv[1][0] == '-' && argv[1][1] == 'h')
 403     genheader ();
 404   else
 405     gencode ();
 406
 407   fflush (stdout);
 408   return (ferror (stdout) != 0 ? FATAL_EXIT_CODE : SUCCESS_EXIT_CODE);
 409 }