diff options
Diffstat (limited to 'util/host-utils.c')
-rw-r--r-- | util/host-utils.c | 105 |
1 files changed, 105 insertions, 0 deletions
diff --git a/util/host-utils.c b/util/host-utils.c new file mode 100644 index 0000000000..5e3915abba --- /dev/null +++ b/util/host-utils.c @@ -0,0 +1,105 @@ +/* + * Utility compute operations used by translated code. + * + * Copyright (c) 2003 Fabrice Bellard + * Copyright (c) 2007 Aurelien Jarno + * + * Permission is hereby granted, free of charge, to any person obtaining a copy + * of this software and associated documentation files (the "Software"), to deal + * in the Software without restriction, including without limitation the rights + * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell + * copies of the Software, and to permit persons to whom the Software is + * furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice shall be included in + * all copies or substantial portions of the Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, + * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN + * THE SOFTWARE. + */ + +#include <stdlib.h> +#include <stdint.h> +#include "qemu/host-utils.h" + +//#define DEBUG_MULDIV + +/* Long integer helpers */ +#if !defined(__x86_64__) +static void add128 (uint64_t *plow, uint64_t *phigh, uint64_t a, uint64_t b) +{ + *plow += a; + /* carry test */ + if (*plow < a) + (*phigh)++; + *phigh += b; +} + +static void neg128 (uint64_t *plow, uint64_t *phigh) +{ + *plow = ~*plow; + *phigh = ~*phigh; + add128(plow, phigh, 1, 0); +} + +static void mul64 (uint64_t *plow, uint64_t *phigh, uint64_t a, uint64_t b) +{ + uint32_t a0, a1, b0, b1; + uint64_t v; + + a0 = a; + a1 = a >> 32; + + b0 = b; + b1 = b >> 32; + + v = (uint64_t)a0 * (uint64_t)b0; + *plow = v; + *phigh = 0; + + v = (uint64_t)a0 * (uint64_t)b1; + add128(plow, phigh, v << 32, v >> 32); + + v = (uint64_t)a1 * (uint64_t)b0; + add128(plow, phigh, v << 32, v >> 32); + + v = (uint64_t)a1 * (uint64_t)b1; + *phigh += v; +} + +/* Unsigned 64x64 -> 128 multiplication */ +void mulu64 (uint64_t *plow, uint64_t *phigh, uint64_t a, uint64_t b) +{ + mul64(plow, phigh, a, b); +#if defined(DEBUG_MULDIV) + printf("mulu64: 0x%016llx * 0x%016llx = 0x%016llx%016llx\n", + a, b, *phigh, *plow); +#endif +} + +/* Signed 64x64 -> 128 multiplication */ +void muls64 (uint64_t *plow, uint64_t *phigh, int64_t a, int64_t b) +{ + int sa, sb; + + sa = (a < 0); + if (sa) + a = -a; + sb = (b < 0); + if (sb) + b = -b; + mul64(plow, phigh, a, b); + if (sa ^ sb) { + neg128(plow, phigh); + } +#if defined(DEBUG_MULDIV) + printf("muls64: 0x%016llx * 0x%016llx = 0x%016llx%016llx\n", + a, b, *phigh, *plow); +#endif +} +#endif /* !defined(__x86_64__) */ |