1 /*
2 * S/390 integer helper routines
3 *
4 * Copyright (c) 2009 Ulrich Hecht
5 * Copyright (c) 2009 Alexander Graf
6 *
7 * This library is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU Lesser General Public
9 * License as published by the Free Software Foundation; either
10 * version 2.1 of the License, or (at your option) any later version.
11 *
12 * This library is distributed in the hope that it will be useful,
13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15 * Lesser General Public License for more details.
16 *
17 * You should have received a copy of the GNU Lesser General Public
18 * License along with this library; if not, see <http://www.gnu.org/licenses/>.
19 */
20
21 #include "qemu/osdep.h"
22 #include "cpu.h"
23 #include "s390x-internal.h"
24 #include "tcg_s390x.h"
25 #include "exec/exec-all.h"
26 #include "qemu/host-utils.h"
27 #include "exec/helper-proto.h"
28
29 /* #define DEBUG_HELPER */
30 #ifdef DEBUG_HELPER
31 #define HELPER_LOG(x...) qemu_log(x)
32 #else
33 #define HELPER_LOG(x...)
34 #endif
35
36 /* 64/32 -> 32 signed division */
HELPER(divs32)37 uint64_t HELPER(divs32)(CPUS390XState *env, int64_t a, int64_t b64)
38 {
39 int32_t b = b64;
40 int64_t q, r;
41
42 if (b == 0) {
43 tcg_s390_program_interrupt(env, PGM_FIXPT_DIVIDE, GETPC());
44 }
45
46 q = a / b;
47 r = a % b;
48
49 /* Catch non-representable quotient. */
50 if (q != (int32_t)q) {
51 tcg_s390_program_interrupt(env, PGM_FIXPT_DIVIDE, GETPC());
52 }
53
54 return deposit64(q, 32, 32, r);
55 }
56
57 /* 64/32 -> 32 unsigned division */
HELPER(divu32)58 uint64_t HELPER(divu32)(CPUS390XState *env, uint64_t a, uint64_t b64)
59 {
60 uint32_t b = b64;
61 uint64_t q, r;
62
63 if (b == 0) {
64 tcg_s390_program_interrupt(env, PGM_FIXPT_DIVIDE, GETPC());
65 }
66
67 q = a / b;
68 r = a % b;
69
70 /* Catch non-representable quotient. */
71 if (q != (uint32_t)q) {
72 tcg_s390_program_interrupt(env, PGM_FIXPT_DIVIDE, GETPC());
73 }
74
75 return deposit64(q, 32, 32, r);
76 }
77
78 /* 64/64 -> 64 signed division */
HELPER(divs64)79 Int128 HELPER(divs64)(CPUS390XState *env, int64_t a, int64_t b)
80 {
81 /* Catch divide by zero, and non-representable quotient (MIN / -1). */
82 if (b == 0 || (b == -1 && a == (1ll << 63))) {
83 tcg_s390_program_interrupt(env, PGM_FIXPT_DIVIDE, GETPC());
84 }
85 return int128_make128(a / b, a % b);
86 }
87
88 /* 128 -> 64/64 unsigned division */
HELPER(divu64)89 Int128 HELPER(divu64)(CPUS390XState *env, uint64_t ah, uint64_t al, uint64_t b)
90 {
91 if (b != 0) {
92 uint64_t r = divu128(&al, &ah, b);
93 if (ah == 0) {
94 return int128_make128(al, r);
95 }
96 }
97 /* divide by zero or overflow */
98 tcg_s390_program_interrupt(env, PGM_FIXPT_DIVIDE, GETPC());
99 }
100
HELPER(cvd)101 uint64_t HELPER(cvd)(int32_t reg)
102 {
103 /* positive 0 */
104 uint64_t dec = 0x0c;
105 int64_t bin = reg;
106 int shift;
107
108 if (bin < 0) {
109 bin = -bin;
110 dec = 0x0d;
111 }
112
113 for (shift = 4; (shift < 64) && bin; shift += 4) {
114 dec |= (bin % 10) << shift;
115 bin /= 10;
116 }
117
118 return dec;
119 }
120
HELPER(popcnt)121 uint64_t HELPER(popcnt)(uint64_t val)
122 {
123 /* Note that we don't fold past bytes. */
124 val = (val & 0x5555555555555555ULL) + ((val >> 1) & 0x5555555555555555ULL);
125 val = (val & 0x3333333333333333ULL) + ((val >> 2) & 0x3333333333333333ULL);
126 val = (val + (val >> 4)) & 0x0f0f0f0f0f0f0f0fULL;
127 return val;
128 }
129