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2#ifndef _ASM_GENERIC_DIV64_H
3#define _ASM_GENERIC_DIV64_H
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24#include <linux/types.h>
25#include <linux/compiler.h>
26
27#if BITS_PER_LONG == 64
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43# define do_div(n,base) ({ \
44 uint32_t __base = (base); \
45 uint32_t __rem; \
46 __rem = ((uint64_t)(n)) % __base; \
47 (n) = ((uint64_t)(n)) / __base; \
48 __rem; \
49 })
50
51#elif BITS_PER_LONG == 32
52
53#include <linux/log2.h>
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65#ifndef __div64_const32_is_OK
66#define __div64_const32_is_OK (__GNUC__ >= 4)
67#endif
68
69#define __div64_const32(n, ___b) \
70({ \
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79 \
80 uint64_t ___res, ___x, ___t, ___m, ___n = (n); \
81 uint32_t ___p, ___bias; \
82 \
83 \
84 ___p = 1 << ilog2(___b); \
85 \
86 \
87 ___m = (~0ULL / ___b) * ___p; \
88 ___m += (((~0ULL % ___b + 1) * ___p) + ___b - 1) / ___b; \
89 \
90 \
91 ___x = ~0ULL / ___b * ___b - 1; \
92 \
93 \
94 ___res = ((___m & 0xffffffff) * (___x & 0xffffffff)) >> 32; \
95 ___t = ___res += (___m & 0xffffffff) * (___x >> 32); \
96 ___res += (___x & 0xffffffff) * (___m >> 32); \
97 ___t = (___res < ___t) ? (1ULL << 32) : 0; \
98 ___res = (___res >> 32) + ___t; \
99 ___res += (___m >> 32) * (___x >> 32); \
100 ___res /= ___p; \
101 \
102 \
103 if (~0ULL % (___b / (___b & -___b)) == 0) { \
104 \
105 ___n /= (___b & -___b); \
106 ___m = ~0ULL / (___b / (___b & -___b)); \
107 ___p = 1; \
108 ___bias = 1; \
109 } else if (___res != ___x / ___b) { \
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117 \
118 ___bias = 1; \
119 \
120 ___m = (~0ULL / ___b) * ___p; \
121 ___m += ((~0ULL % ___b + 1) * ___p) / ___b; \
122 } else { \
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127 \
128 uint32_t ___bits = -(___m & -___m); \
129 ___bits |= ___m >> 32; \
130 ___bits = (~___bits) << 1; \
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136 \
137 if (!___bits) { \
138 ___p /= (___m & -___m); \
139 ___m /= (___m & -___m); \
140 } else { \
141 ___p >>= ilog2(___bits); \
142 ___m >>= ilog2(___bits); \
143 } \
144 \
145 ___bias = 0; \
146 } \
147 \
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158 \
159 ___res = __arch_xprod_64(___m, ___n, ___bias); \
160 \
161 ___res /= ___p; \
162})
163
164#ifndef __arch_xprod_64
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175static inline uint64_t __arch_xprod_64(const uint64_t m, uint64_t n, bool bias)
176{
177 uint32_t m_lo = m;
178 uint32_t m_hi = m >> 32;
179 uint32_t n_lo = n;
180 uint32_t n_hi = n >> 32;
181 uint64_t res, tmp;
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183 if (!bias) {
184 res = ((uint64_t)m_lo * n_lo) >> 32;
185 } else if (!(m & ((1ULL << 63) | (1ULL << 31)))) {
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187 res = (m + (uint64_t)m_lo * n_lo) >> 32;
188 } else {
189 res = m + (uint64_t)m_lo * n_lo;
190 tmp = (res < m) ? (1ULL << 32) : 0;
191 res = (res >> 32) + tmp;
192 }
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194 if (!(m & ((1ULL << 63) | (1ULL << 31)))) {
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196 res += (uint64_t)m_lo * n_hi;
197 res += (uint64_t)m_hi * n_lo;
198 res >>= 32;
199 } else {
200 tmp = res += (uint64_t)m_lo * n_hi;
201 res += (uint64_t)m_hi * n_lo;
202 tmp = (res < tmp) ? (1ULL << 32) : 0;
203 res = (res >> 32) + tmp;
204 }
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206 res += (uint64_t)m_hi * n_hi;
207
208 return res;
209}
210#endif
211
212#ifndef __div64_32
213extern uint32_t __div64_32(uint64_t *dividend, uint32_t divisor);
214#endif
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219# define do_div(n,base) ({ \
220 uint32_t __base = (base); \
221 uint32_t __rem; \
222 (void)(((typeof((n)) *)0) == ((uint64_t *)0)); \
223 if (__builtin_constant_p(__base) && \
224 is_power_of_2(__base)) { \
225 __rem = (n) & (__base - 1); \
226 (n) >>= ilog2(__base); \
227 } else if (__div64_const32_is_OK && \
228 __builtin_constant_p(__base) && \
229 __base != 0) { \
230 uint32_t __res_lo, __n_lo = (n); \
231 (n) = __div64_const32(n, __base); \
232 \
233 __res_lo = (n); \
234 __rem = __n_lo - __res_lo * __base; \
235 } else if (likely(((n) >> 32) == 0)) { \
236 __rem = (uint32_t)(n) % __base; \
237 (n) = (uint32_t)(n) / __base; \
238 } else \
239 __rem = __div64_32(&(n), __base); \
240 __rem; \
241 })
242
243#else
244
245# error do_div() does not yet support the C64
246
247#endif
248
249#endif
250