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26#include "qemu/osdep.h"
27#include "qemu/host-utils.h"
28
29#ifndef CONFIG_INT128
30
31static inline void mul64(uint64_t *plow, uint64_t *phigh,
32 uint64_t a, uint64_t b)
33{
34 typedef union {
35 uint64_t ll;
36 struct {
37#ifdef HOST_WORDS_BIGENDIAN
38 uint32_t high, low;
39#else
40 uint32_t low, high;
41#endif
42 } l;
43 } LL;
44 LL rl, rm, rn, rh, a0, b0;
45 uint64_t c;
46
47 a0.ll = a;
48 b0.ll = b;
49
50 rl.ll = (uint64_t)a0.l.low * b0.l.low;
51 rm.ll = (uint64_t)a0.l.low * b0.l.high;
52 rn.ll = (uint64_t)a0.l.high * b0.l.low;
53 rh.ll = (uint64_t)a0.l.high * b0.l.high;
54
55 c = (uint64_t)rl.l.high + rm.l.low + rn.l.low;
56 rl.l.high = c;
57 c >>= 32;
58 c = c + rm.l.high + rn.l.high + rh.l.low;
59 rh.l.low = c;
60 rh.l.high += (uint32_t)(c >> 32);
61
62 *plow = rl.ll;
63 *phigh = rh.ll;
64}
65
66
67void mulu64 (uint64_t *plow, uint64_t *phigh, uint64_t a, uint64_t b)
68{
69 mul64(plow, phigh, a, b);
70}
71
72
73void muls64 (uint64_t *plow, uint64_t *phigh, int64_t a, int64_t b)
74{
75 uint64_t rh;
76
77 mul64(plow, &rh, a, b);
78
79
80 if (b < 0) {
81 rh -= a;
82 }
83 if (a < 0) {
84 rh -= b;
85 }
86 *phigh = rh;
87}
88
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92
93
94
95uint64_t divu128(uint64_t *plow, uint64_t *phigh, uint64_t divisor)
96{
97 uint64_t dhi = *phigh;
98 uint64_t dlo = *plow;
99 uint64_t rem, dhighest;
100 int sh;
101
102 if (divisor == 0 || dhi == 0) {
103 *plow = dlo / divisor;
104 *phigh = 0;
105 return dlo % divisor;
106 } else {
107 sh = clz64(divisor);
108
109 if (dhi < divisor) {
110 if (sh != 0) {
111
112 divisor <<= sh;
113 dhi = (dhi << sh) | (dlo >> (64 - sh));
114 dlo <<= sh;
115 }
116
117 *phigh = 0;
118 *plow = udiv_qrnnd(&rem, dhi, dlo, divisor);
119 } else {
120 if (sh != 0) {
121
122 divisor <<= sh;
123 dhighest = dhi >> (64 - sh);
124 dhi = (dhi << sh) | (dlo >> (64 - sh));
125 dlo <<= sh;
126
127 *phigh = udiv_qrnnd(&dhi, dhighest, dhi, divisor);
128 } else {
129
130
131
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133
134
135
136
137
138 dhi -= divisor;
139 *phigh = 1;
140 }
141
142 *plow = udiv_qrnnd(&rem, dhi, dlo, divisor);
143 }
144
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147
148
149 return rem >> sh;
150 }
151}
152
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157
158int64_t divs128(uint64_t *plow, int64_t *phigh, int64_t divisor)
159{
160 bool neg_quotient = false, neg_remainder = false;
161 uint64_t unsig_hi = *phigh, unsig_lo = *plow;
162 uint64_t rem;
163
164 if (*phigh < 0) {
165 neg_quotient = !neg_quotient;
166 neg_remainder = !neg_remainder;
167
168 if (unsig_lo == 0) {
169 unsig_hi = -unsig_hi;
170 } else {
171 unsig_hi = ~unsig_hi;
172 unsig_lo = -unsig_lo;
173 }
174 }
175
176 if (divisor < 0) {
177 neg_quotient = !neg_quotient;
178
179 divisor = -divisor;
180 }
181
182 rem = divu128(&unsig_lo, &unsig_hi, (uint64_t)divisor);
183
184 if (neg_quotient) {
185 if (unsig_lo == 0) {
186 *phigh = -unsig_hi;
187 *plow = 0;
188 } else {
189 *phigh = ~unsig_hi;
190 *plow = -unsig_lo;
191 }
192 } else {
193 *phigh = unsig_hi;
194 *plow = unsig_lo;
195 }
196
197 if (neg_remainder) {
198 return -rem;
199 } else {
200 return rem;
201 }
202}
203#endif
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215
216void urshift(uint64_t *plow, uint64_t *phigh, int32_t shift)
217{
218 shift &= 127;
219 if (shift == 0) {
220 return;
221 }
222
223 uint64_t h = *phigh >> (shift & 63);
224 if (shift >= 64) {
225 *plow = h;
226 *phigh = 0;
227 } else {
228 *plow = (*plow >> (shift & 63)) | (*phigh << (64 - (shift & 63)));
229 *phigh = h;
230 }
231}
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243
244
245void ulshift(uint64_t *plow, uint64_t *phigh, int32_t shift, bool *overflow)
246{
247 uint64_t low = *plow;
248 uint64_t high = *phigh;
249
250 shift &= 127;
251 if (shift == 0) {
252 return;
253 }
254
255
256 urshift(&low, &high, 128 - shift);
257 if (low | high) {
258 *overflow = true;
259 }
260
261 if (shift >= 64) {
262 *phigh = *plow << (shift & 63);
263 *plow = 0;
264 } else {
265 *phigh = (*plow >> (64 - (shift & 63))) | (*phigh << (shift & 63));
266 *plow = *plow << shift;
267 }
268}
269