gcc/hwint.h

   1 /* HOST_WIDE_INT definitions for the GNU compiler.
   2    Copyright (C) 1998, 2002, 2004, 2008, 2009, 2010
   3    Free Software Foundation, Inc.
   4
   5    This file is part of GCC.
   6
   7    Provide definitions for macros which depend on HOST_BITS_PER_INT
   8    and HOST_BITS_PER_LONG.  */
   9
  10 #ifndef GCC_HWINT_H
  11 #define GCC_HWINT_H
  12
  13 /* This describes the machine the compiler is hosted on.  */
  14 #define HOST_BITS_PER_CHAR  CHAR_BIT
  15 #define HOST_BITS_PER_SHORT (CHAR_BIT * SIZEOF_SHORT)
  16 #define HOST_BITS_PER_INT   (CHAR_BIT * SIZEOF_INT)
  17 #define HOST_BITS_PER_LONG  (CHAR_BIT * SIZEOF_LONG)
  18
  19 /* The string that should be inserted into a printf style format to
  20    indicate a "long" operand.  */
  21 #ifndef HOST_LONG_FORMAT
  22 #define HOST_LONG_FORMAT "l"
  23 #endif
  24
  25 /* The string that should be inserted into a printf style format to
  26    indicate a "long long" operand.  */
  27 #ifndef HOST_LONG_LONG_FORMAT
  28 #define HOST_LONG_LONG_FORMAT "ll"
  29 #endif
  30
  31 /* If HAVE_LONG_LONG and SIZEOF_LONG_LONG aren't defined, but
  32    GCC_VERSION >= 3000, assume this is the second or later stage of a
  33    bootstrap, we do have long long, and it's 64 bits.  (This is
  34    required by C99; we do have some ports that violate that assumption
  35    but they're all cross-compile-only.)  Just in case, force a
  36    constraint violation if that assumption is incorrect.  */
  37 #if !defined HAVE_LONG_LONG
  38 # if GCC_VERSION >= 3000
  39 #  define HAVE_LONG_LONG 1
  40 #  define SIZEOF_LONG_LONG 8
  41 extern char sizeof_long_long_must_be_8[sizeof(long long) == 8 ? 1 : -1];
  42 # endif
  43 #endif
  44
  45 #ifdef HAVE_LONG_LONG
  46 # define HOST_BITS_PER_LONGLONG (CHAR_BIT * SIZEOF_LONG_LONG)
  47 #endif
  48 #ifdef HAVE___INT64
  49 # define HOST_BITS_PER___INT64 (CHAR_BIT * SIZEOF___INT64)
  50 #endif
  51
  52 /* Set HOST_WIDE_INT.  This should be the widest efficient host
  53    integer type.  It can be 32 or 64 bits, except that if we are
  54    targeting a machine with 64-bit size_t then it has to be 64 bits.
  55
  56    With a sane ABI, 'long' is the largest efficient host integer type.
  57    Thus, we use that unless we have to use 'long long' or '__int64'
  58    because we're targeting a 64-bit machine from a 32-bit host.  */
  59
  60 #if HOST_BITS_PER_LONG >= 64 || !defined NEED_64BIT_HOST_WIDE_INT
  61 #   define HOST_BITS_PER_WIDE_INT HOST_BITS_PER_LONG
  62 #   define HOST_WIDE_INT long
  63 #else
  64 # if HOST_BITS_PER_LONGLONG >= 64
  65 #   define HOST_BITS_PER_WIDE_INT HOST_BITS_PER_LONGLONG
  66 #   define HOST_WIDE_INT long long
  67 # else
  68 #  if HOST_BITS_PER___INT64 >= 64
  69 #   define HOST_BITS_PER_WIDE_INT HOST_BITS_PER___INT64
  70 #   define HOST_WIDE_INT __int64
  71 #  else
  72     #error "Unable to find a suitable type for HOST_WIDE_INT"
  73 #  endif
  74 # endif
  75 #endif
  76
  77 /* Various printf format strings for HOST_WIDE_INT.  */
  78
  79 #if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONG
  80 # define HOST_WIDE_INT_PRINT HOST_LONG_FORMAT
  81 # define HOST_WIDE_INT_PRINT_C "L"
  82   /* 'long' might be 32 or 64 bits, and the number of leading zeroes
  83      must be tweaked accordingly.  */
  84 # if HOST_BITS_PER_WIDE_INT == 64
  85 #  define HOST_WIDE_INT_PRINT_DOUBLE_HEX \
  86      "0x%" HOST_LONG_FORMAT "x%016" HOST_LONG_FORMAT "x"
  87 # else
  88 #  define HOST_WIDE_INT_PRINT_DOUBLE_HEX \
  89      "0x%" HOST_LONG_FORMAT "x%08" HOST_LONG_FORMAT "x"
  90 # endif
  91 #else
  92 # define HOST_WIDE_INT_PRINT HOST_LONG_LONG_FORMAT
  93 # define HOST_WIDE_INT_PRINT_C "LL"
  94   /* We can assume that 'long long' is at least 64 bits.  */
  95 # define HOST_WIDE_INT_PRINT_DOUBLE_HEX \
  96     "0x%" HOST_LONG_LONG_FORMAT "x%016" HOST_LONG_LONG_FORMAT "x"
  97 #endif /* HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONG */
  98
  99 #define HOST_WIDE_INT_PRINT_DEC "%" HOST_WIDE_INT_PRINT "d"
 100 #define HOST_WIDE_INT_PRINT_DEC_C HOST_WIDE_INT_PRINT_DEC HOST_WIDE_INT_PRINT_C
 101 #define HOST_WIDE_INT_PRINT_UNSIGNED "%" HOST_WIDE_INT_PRINT "u"
 102 #define HOST_WIDE_INT_PRINT_HEX "%#" HOST_WIDE_INT_PRINT "x"
 103
 104 /* Set HOST_WIDEST_INT.  This is a 64-bit type unless the compiler
 105    in use has no 64-bit type at all; in that case it's 32 bits.  */
 106
 107 #if HOST_BITS_PER_WIDE_INT >= 64 \
 108     || (HOST_BITS_PER_LONGLONG < 64 && HOST_BITS_PER___INT64 < 64)
 109 # define HOST_WIDEST_INT                      HOST_WIDE_INT
 110 # define HOST_BITS_PER_WIDEST_INT             HOST_BITS_PER_WIDE_INT
 111 # define HOST_WIDEST_INT_PRINT                HOST_WIDE_INT_PRINT
 112 # define HOST_WIDEST_INT_PRINT_DEC            HOST_WIDE_INT_PRINT_DEC
 113 # define HOST_WIDEST_INT_PRINT_DEC_C          HOST_WIDE_INT_PRINT_DEC_C
 114 # define HOST_WIDEST_INT_PRINT_UNSIGNED       HOST_WIDE_INT_PRINT_UNSIGNED
 115 # define HOST_WIDEST_INT_PRINT_HEX            HOST_WIDE_INT_PRINT_HEX
 116 # define HOST_WIDEST_INT_PRINT_DOUBLE_HEX     HOST_WIDE_INT_PRINT_DOUBLE_HEX
 117 #else
 118 # if HOST_BITS_PER_LONGLONG >= 64
 119 #  define HOST_BITS_PER_WIDEST_INT            HOST_BITS_PER_LONGLONG
 120 #  define HOST_WIDEST_INT                     long long
 121 # else
 122 #  if HOST_BITS_PER___INT64 >= 64
 123 #   define HOST_BITS_PER_WIDEST_INT           HOST_BITS_PER___INT64
 124 #   define HOST_WIDEST_INT                    __int64
 125 #  else
 126     #error "This line should be impossible to reach"
 127 #  endif
 128 # endif
 129 # define HOST_WIDEST_INT_PRINT                HOST_LONG_LONG_FORMAT
 130 # define HOST_WIDEST_INT_PRINT_DEC            "%" HOST_LONG_LONG_FORMAT "d"
 131 # define HOST_WIDEST_INT_PRINT_DEC_C          "%" HOST_LONG_LONG_FORMAT "dLL"
 132 # define HOST_WIDEST_INT_PRINT_UNSIGNED       "%" HOST_LONG_LONG_FORMAT "u"
 133 # define HOST_WIDEST_INT_PRINT_HEX            "%#" HOST_LONG_LONG_FORMAT "x"
 134 # define HOST_WIDEST_INT_PRINT_DOUBLE_HEX     \
 135     "0x%" HOST_LONG_LONG_FORMAT "x%016" HOST_LONG_LONG_FORMAT "x"
 136 #endif
 137
 138 /* Define HOST_WIDEST_FAST_INT to the widest integer type supported
 139    efficiently in hardware.  (That is, the widest integer type that fits
 140    in a hardware register.)  Normally this is "long" but on some hosts it
 141    should be "long long" or "__int64".  This is no convenient way to
 142    autodetect this, so such systems must set a flag in config.host; see there
 143    for details.  */
 144
 145 #ifdef USE_LONG_LONG_FOR_WIDEST_FAST_INT
 146 #  ifdef HAVE_LONG_LONG
 147 #    define HOST_WIDEST_FAST_INT long long
 148 #    define HOST_BITS_PER_WIDEST_FAST_INT HOST_BITS_PER_LONGLONG
 149 #  elif defined (HAVE___INT64)
 150 #    define HOST_WIDEST_FAST_INT __int64
 151 #    define HOST_BITS_PER_WIDEST_FAST_INT HOST_BITS_PER___INT64
 152 #  else
 153 #    error "Your host said it wanted to use long long or __int64 but neither"
 154 #    error "exist"
 155 #  endif
 156 #else
 157 #  define HOST_WIDEST_FAST_INT long
 158 #  define HOST_BITS_PER_WIDEST_FAST_INT HOST_BITS_PER_LONG
 159 #endif
 160
 161 /* Inline functions operating on HOST_WIDE_INT.  */
 162 #if GCC_VERSION < 3004
 163
 164 extern int clz_hwi (unsigned HOST_WIDE_INT x);
 165 extern int ctz_hwi (unsigned HOST_WIDE_INT x);
 166 extern int ffs_hwi (unsigned HOST_WIDE_INT x);
 167
 168 /* Return log2, or -1 if not exact.  */
 169 extern int exact_log2                  (unsigned HOST_WIDE_INT);
 170
 171 /* Return floor of log2, with -1 for zero.  */
 172 extern int floor_log2                  (unsigned HOST_WIDE_INT);
 173
 174 #else /* GCC_VERSION >= 3004 */
 175
 176 /* For convenience, define 0 -> word_size.  */
 177 static inline int
 178 clz_hwi (unsigned HOST_WIDE_INT x)
 179 {
 180   if (x == 0)
 181     return HOST_BITS_PER_WIDE_INT;
 182 # if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONG
 183   return __builtin_clzl (x);
 184 # elif HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONGLONG
 185   return __builtin_clzll (x);
 186 # else
 187   return __builtin_clz (x);
 188 # endif
 189 }
 190
 191 static inline int
 192 ctz_hwi (unsigned HOST_WIDE_INT x)
 193 {
 194   if (x == 0)
 195     return HOST_BITS_PER_WIDE_INT;
 196 # if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONG
 197   return __builtin_ctzl (x);
 198 # elif HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONGLONG
 199   return __builtin_ctzll (x);
 200 # else
 201   return __builtin_ctz (x);
 202 # endif
 203 }
 204
 205 static inline int
 206 ffs_hwi (unsigned HOST_WIDE_INT x)
 207 {
 208 # if HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONG
 209   return __builtin_ffsl (x);
 210 # elif HOST_BITS_PER_WIDE_INT == HOST_BITS_PER_LONGLONG
 211   return __builtin_ffsll (x);
 212 # else
 213   return __builtin_ffs (x);
 214 # endif
 215 }
 216
 217 static inline int
 218 floor_log2 (unsigned HOST_WIDE_INT x)
 219 {
 220   return HOST_BITS_PER_WIDE_INT - 1 - clz_hwi (x);
 221 }
 222
 223 static inline int
 224 exact_log2 (unsigned HOST_WIDE_INT x)
 225 {
 226   return x == (x & -x) && x ? ctz_hwi (x) : -1;
 227 }
 228
 229 #endif /* GCC_VERSION >= 3004 */
 230
 231 /* Compute the greatest common divisor of two numbers using
 232    Euclid's algorithm.  */
 233
 234 static inline int
 235 gcd (int a, int b)
 236 {
 237   int x, y, z;
 238
 239   x = abs (a);
 240   y = abs (b);
 241
 242   while (x > 0)
 243     {
 244       z = y % x;
 245       y = x;
 246       x = z;
 247     }
 248
 249   return y;
 250 }
 251
 252 /* Compute the least common multiple of two numbers A and B .  */
 253
 254 static inline int
 255 least_common_multiple (int a, int b)
 256 {
 257   return (abs (a) * abs (b) / gcd (a, b));
 258 }
 259
 260 #endif /* ! GCC_HWINT_H */