host-utils.h

   1 /*
   2  * Utility compute operations used by translated code.
   3  *
   4  * Copyright (c) 2007 Thiemo Seufer
   5  * Copyright (c) 2007 Jocelyn Mayer
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a copy
   8  * of this software and associated documentation files (the "Software"), to deal
   9  * in the Software without restriction, including without limitation the rights
  10  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  11  * copies of the Software, and to permit persons to whom the Software is
  12  * furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included in
  15  * all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  20  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  21  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  22  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  23  * THE SOFTWARE.
  24  */
  25
  26 #include "compiler.h"   /* QEMU_GNUC_PREREQ */
  27
  28 #if defined(__x86_64__)
  29 #define __HAVE_FAST_MULU64__
  30 static inline void mulu64(uint64_t *plow, uint64_t *phigh,
  31                           uint64_t a, uint64_t b)
  32 {
  33     __asm__ ("mul %0\n\t"
  34              : "=d" (*phigh), "=a" (*plow)
  35              : "a" (a), "0" (b));
  36 }
  37 #define __HAVE_FAST_MULS64__
  38 static inline void muls64(uint64_t *plow, uint64_t *phigh,
  39                           int64_t a, int64_t b)
  40 {
  41     __asm__ ("imul %0\n\t"
  42              : "=d" (*phigh), "=a" (*plow)
  43              : "a" (a), "0" (b));
  44 }
  45 #else
  46 void muls64(uint64_t *phigh, uint64_t *plow, int64_t a, int64_t b);
  47 void mulu64(uint64_t *phigh, uint64_t *plow, uint64_t a, uint64_t b);
  48 #endif
  49
  50 /* Binary search for leading zeros.  */
  51
  52 static inline int clz32(uint32_t val)
  53 {
  54 #if QEMU_GNUC_PREREQ(3, 4)
  55     if (val)
  56         return __builtin_clz(val);
  57     else
  58         return 32;
  59 #else
  60     int cnt = 0;
  61
  62     if (!(val & 0xFFFF0000U)) {
  63         cnt += 16;
  64         val <<= 16;
  65     }
  66     if (!(val & 0xFF000000U)) {
  67         cnt += 8;
  68         val <<= 8;
  69     }
  70     if (!(val & 0xF0000000U)) {
  71         cnt += 4;
  72         val <<= 4;
  73     }
  74     if (!(val & 0xC0000000U)) {
  75         cnt += 2;
  76         val <<= 2;
  77     }
  78     if (!(val & 0x80000000U)) {
  79         cnt++;
  80         val <<= 1;
  81     }
  82     if (!(val & 0x80000000U)) {
  83         cnt++;
  84     }
  85     return cnt;
  86 #endif
  87 }
  88
  89 static inline int clo32(uint32_t val)
  90 {
  91     return clz32(~val);
  92 }
  93
  94 static inline int clz64(uint64_t val)
  95 {
  96 #if QEMU_GNUC_PREREQ(3, 4)
  97     if (val)
  98         return __builtin_clzll(val);
  99     else
 100         return 64;
 101 #else
 102     int cnt = 0;
 103
 104     if (!(val >> 32)) {
 105         cnt += 32;
 106     } else {
 107         val >>= 32;
 108     }
 109
 110     return cnt + clz32(val);
 111 #endif
 112 }
 113
 114 static inline int clo64(uint64_t val)
 115 {
 116     return clz64(~val);
 117 }
 118
 119 static inline int ctz32(uint32_t val)
 120 {
 121 #if QEMU_GNUC_PREREQ(3, 4)
 122     if (val)
 123         return __builtin_ctz(val);
 124     else
 125         return 32;
 126 #else
 127     int cnt;
 128
 129     cnt = 0;
 130     if (!(val & 0x0000FFFFUL)) {
 131         cnt += 16;
 132         val >>= 16;
 133     }
 134     if (!(val & 0x000000FFUL)) {
 135         cnt += 8;
 136         val >>= 8;
 137     }
 138     if (!(val & 0x0000000FUL)) {
 139         cnt += 4;
 140         val >>= 4;
 141     }
 142     if (!(val & 0x00000003UL)) {
 143         cnt += 2;
 144         val >>= 2;
 145     }
 146     if (!(val & 0x00000001UL)) {
 147         cnt++;
 148         val >>= 1;
 149     }
 150     if (!(val & 0x00000001UL)) {
 151         cnt++;
 152     }
 153
 154     return cnt;
 155 #endif
 156 }
 157
 158 static inline int cto32(uint32_t val)
 159 {
 160     return ctz32(~val);
 161 }
 162
 163 static inline int ctz64(uint64_t val)
 164 {
 165 #if QEMU_GNUC_PREREQ(3, 4)
 166     if (val)
 167         return __builtin_ctzll(val);
 168     else
 169         return 64;
 170 #else
 171     int cnt;
 172
 173     cnt = 0;
 174     if (!((uint32_t)val)) {
 175         cnt += 32;
 176         val >>= 32;
 177     }
 178
 179     return cnt + ctz32(val);
 180 #endif
 181 }
 182
 183 static inline int cto64(uint64_t val)
 184 {
 185     return ctz64(~val);
 186 }
 187
 188 static inline int ctpop8(uint8_t val)
 189 {
 190     val = (val & 0x55) + ((val >> 1) & 0x55);
 191     val = (val & 0x33) + ((val >> 2) & 0x33);
 192     val = (val & 0x0f) + ((val >> 4) & 0x0f);
 193
 194     return val;
 195 }
 196
 197 static inline int ctpop16(uint16_t val)
 198 {
 199     val = (val & 0x5555) + ((val >> 1) & 0x5555);
 200     val = (val & 0x3333) + ((val >> 2) & 0x3333);
 201     val = (val & 0x0f0f) + ((val >> 4) & 0x0f0f);
 202     val = (val & 0x00ff) + ((val >> 8) & 0x00ff);
 203
 204     return val;
 205 }
 206
 207 static inline int ctpop32(uint32_t val)
 208 {
 209 #if QEMU_GNUC_PREREQ(3, 4)
 210     return __builtin_popcount(val);
 211 #else
 212     val = (val & 0x55555555) + ((val >>  1) & 0x55555555);
 213     val = (val & 0x33333333) + ((val >>  2) & 0x33333333);
 214     val = (val & 0x0f0f0f0f) + ((val >>  4) & 0x0f0f0f0f);
 215     val = (val & 0x00ff00ff) + ((val >>  8) & 0x00ff00ff);
 216     val = (val & 0x0000ffff) + ((val >> 16) & 0x0000ffff);
 217
 218     return val;
 219 #endif
 220 }
 221
 222 static inline int ctpop64(uint64_t val)
 223 {
 224 #if QEMU_GNUC_PREREQ(3, 4)
 225     return __builtin_popcountll(val);
 226 #else
 227     val = (val & 0x5555555555555555ULL) + ((val >>  1) & 0x5555555555555555ULL);
 228     val = (val & 0x3333333333333333ULL) + ((val >>  2) & 0x3333333333333333ULL);
 229     val = (val & 0x0f0f0f0f0f0f0f0fULL) + ((val >>  4) & 0x0f0f0f0f0f0f0f0fULL);
 230     val = (val & 0x00ff00ff00ff00ffULL) + ((val >>  8) & 0x00ff00ff00ff00ffULL);
 231     val = (val & 0x0000ffff0000ffffULL) + ((val >> 16) & 0x0000ffff0000ffffULL);
 232     val = (val & 0x00000000ffffffffULL) + ((val >> 32) & 0x00000000ffffffffULL);
 233
 234     return val;
 235 #endif
 236 }