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1/* SPDX-License-Identifier: GPL-2.0 */2#ifndef _LINUX_MATH64_H3#define _LINUX_MATH64_H4 5#include <linux/types.h>6 7#ifdef __x86_64__8static inline u64 mul_u64_u64_div64(u64 a, u64 b, u64 c)9{10 u64 q;11 12 asm ("mulq %2; divq %3" : "=a" (q)13 : "a" (a), "rm" (b), "rm" (c)14 : "rdx");15 16 return q;17}18#define mul_u64_u64_div64 mul_u64_u64_div6419#endif20 21#ifdef __SIZEOF_INT128__22static inline u64 mul_u64_u32_shr(u64 a, u32 b, unsigned int shift)23{24 return (u64)(((unsigned __int128)a * b) >> shift);25}26 27#else28 29#ifdef __i386__30static inline u64 mul_u32_u32(u32 a, u32 b)31{32 u32 high, low;33 34 asm ("mull %[b]" : "=a" (low), "=d" (high)35 : [a] "a" (a), [b] "rm" (b) );36 37 return low | ((u64)high) << 32;38}39#else40static inline u64 mul_u32_u32(u32 a, u32 b)41{42 return (u64)a * b;43}44#endif45 46static inline u64 mul_u64_u32_shr(u64 a, u32 b, unsigned int shift)47{48 u32 ah, al;49 u64 ret;50 51 al = a;52 ah = a >> 32;53 54 ret = mul_u32_u32(al, b) >> shift;55 if (ah)56 ret += mul_u32_u32(ah, b) << (32 - shift);57 58 return ret;59}60 61#endif /* __SIZEOF_INT128__ */62 63#ifndef mul_u64_u64_div6464static inline u64 mul_u64_u64_div64(u64 a, u64 b, u64 c)65{66 u64 quot, rem;67 68 quot = a / c;69 rem = a % c;70 71 return quot * b + (rem * b) / c;72}73#endif74 75#endif /* _LINUX_MATH64_H */76