summaryrefslogtreecommitdiff
path: root/target-s390x/int_helper.c
blob: a46c736d67bc66388225c60a3059850955d014a7 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
/*
 *  S/390 integer helper routines
 *
 *  Copyright (c) 2009 Ulrich Hecht
 *  Copyright (c) 2009 Alexander Graf
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
 */

#include "cpu.h"
#include "qemu/host-utils.h"
#include "exec/helper-proto.h"

/* #define DEBUG_HELPER */
#ifdef DEBUG_HELPER
#define HELPER_LOG(x...) qemu_log(x)
#else
#define HELPER_LOG(x...)
#endif

/* 64/32 -> 32 signed division */
int64_t HELPER(divs32)(CPUS390XState *env, int64_t a, int64_t b64)
{
    int32_t ret, b = b64;
    int64_t q;

    if (b == 0) {
        runtime_exception(env, PGM_FIXPT_DIVIDE, GETPC());
    }

    ret = q = a / b;
    env->retxl = a % b;

    /* Catch non-representable quotient.  */
    if (ret != q) {
        runtime_exception(env, PGM_FIXPT_DIVIDE, GETPC());
    }

    return ret;
}

/* 64/32 -> 32 unsigned division */
uint64_t HELPER(divu32)(CPUS390XState *env, uint64_t a, uint64_t b64)
{
    uint32_t ret, b = b64;
    uint64_t q;

    if (b == 0) {
        runtime_exception(env, PGM_FIXPT_DIVIDE, GETPC());
    }

    ret = q = a / b;
    env->retxl = a % b;

    /* Catch non-representable quotient.  */
    if (ret != q) {
        runtime_exception(env, PGM_FIXPT_DIVIDE, GETPC());
    }

    return ret;
}

/* 64/64 -> 64 signed division */
int64_t HELPER(divs64)(CPUS390XState *env, int64_t a, int64_t b)
{
    /* Catch divide by zero, and non-representable quotient (MIN / -1).  */
    if (b == 0 || (b == -1 && a == (1ll << 63))) {
        runtime_exception(env, PGM_FIXPT_DIVIDE, GETPC());
    }
    env->retxl = a % b;
    return a / b;
}

/* 128 -> 64/64 unsigned division */
uint64_t HELPER(divu64)(CPUS390XState *env, uint64_t ah, uint64_t al,
                        uint64_t b)
{
    uint64_t ret;
    /* Signal divide by zero.  */
    if (b == 0) {
        runtime_exception(env, PGM_FIXPT_DIVIDE, GETPC());
    }
    if (ah == 0) {
        /* 64 -> 64/64 case */
        env->retxl = al % b;
        ret = al / b;
    } else {
        /* ??? Move i386 idivq helper to host-utils.  */
#ifdef CONFIG_INT128
        __uint128_t a = ((__uint128_t)ah << 64) | al;
        __uint128_t q = a / b;
        env->retxl = a % b;
        ret = q;
        if (ret != q) {
            runtime_exception(env, PGM_FIXPT_DIVIDE, GETPC());
        }
#else
        S390CPU *cpu = s390_env_get_cpu(env);
        /* 32-bit hosts would need special wrapper functionality - just abort if
           we encounter such a case; it's very unlikely anyways. */
        cpu_abort(CPU(cpu), "128 -> 64/64 division not implemented\n");
#endif
    }
    return ret;
}

/* count leading zeros, for find leftmost one */
uint64_t HELPER(clz)(uint64_t v)
{
    return clz64(v);
}

uint64_t HELPER(cvd)(int32_t reg)
{
    /* positive 0 */
    uint64_t dec = 0x0c;
    int64_t bin = reg;
    int shift;

    if (bin < 0) {
        bin = -bin;
        dec = 0x0d;
    }

    for (shift = 4; (shift < 64) && bin; shift += 4) {
        dec |= (bin % 10) << shift;
        bin /= 10;
    }

    return dec;
}

uint64_t HELPER(popcnt)(uint64_t r2)
{
    uint64_t ret = 0;
    int i;

    for (i = 0; i < 64; i += 8) {
        uint64_t t = ctpop32((r2 >> i) & 0xff);
        ret |= t << i;
    }
    return ret;
}