1/*
2 * Utility compute operations used by translated code.
3 *
4 * Copyright (c) 2003 Fabrice Bellard
5 * Copyright (c) 2007 Aurelien Jarno
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 <stdlib.h>
27#include <stdint.h>
28#include "host-utils.h"
29
30//#define DEBUG_MULDIV
31
32/* Long integer helpers */
33#if !defined(__x86_64__)
34static void add128 (uint64_t *plow, uint64_t *phigh, uint64_t a, uint64_t b)
35{
36    *plow += a;
37    /* carry test */
38    if (*plow < a)
39        (*phigh)++;
40    *phigh += b;
41}
42
43static void neg128 (uint64_t *plow, uint64_t *phigh)
44{
45    *plow = ~*plow;
46    *phigh = ~*phigh;
47    add128(plow, phigh, 1, 0);
48}
49
50static void mul64 (uint64_t *plow, uint64_t *phigh, uint64_t a, uint64_t b)
51{
52    uint32_t a0, a1, b0, b1;
53    uint64_t v;
54
55    a0 = a;
56    a1 = a >> 32;
57
58    b0 = b;
59    b1 = b >> 32;
60
61    v = (uint64_t)a0 * (uint64_t)b0;
62    *plow = v;
63    *phigh = 0;
64
65    v = (uint64_t)a0 * (uint64_t)b1;
66    add128(plow, phigh, v << 32, v >> 32);
67
68    v = (uint64_t)a1 * (uint64_t)b0;
69    add128(plow, phigh, v << 32, v >> 32);
70
71    v = (uint64_t)a1 * (uint64_t)b1;
72    *phigh += v;
73}
74
75/* Unsigned 64x64 -> 128 multiplication */
76void mulu64 (uint64_t *plow, uint64_t *phigh, uint64_t a, uint64_t b)
77{
78    mul64(plow, phigh, a, b);
79#if defined(DEBUG_MULDIV)
80    printf("mulu64: 0x%016llx * 0x%016llx = 0x%016llx%016llx\n",
81           a, b, *phigh, *plow);
82#endif
83}
84
85/* Signed 64x64 -> 128 multiplication */
86void muls64 (uint64_t *plow, uint64_t *phigh, int64_t a, int64_t b)
87{
88    int sa, sb;
89
90    sa = (a < 0);
91    if (sa)
92        a = -a;
93    sb = (b < 0);
94    if (sb)
95        b = -b;
96    mul64(plow, phigh, a, b);
97    if (sa ^ sb) {
98        neg128(plow, phigh);
99    }
100#if defined(DEBUG_MULDIV)
101    printf("muls64: 0x%016llx * 0x%016llx = 0x%016llx%016llx\n",
102           a, b, *phigh, *plow);
103#endif
104}
105#endif /* !defined(__x86_64__) */
106