From e1660dc57c1bacb78cbe39001e58a577c927dacb Mon Sep 17 00:00:00 2001 From: Frediano Ziglio Date: Fri, 9 Jan 2015 11:25:20 +0000 Subject: [PATCH] qemu-common.h: optimise muldiv64 if int128 is available Let compiler do the job to optimise the function. Signed-off-by: Frediano Ziglio Signed-off-by: Paolo Bonzini Signed-off-by: Frediano Ziglio --- include/qemu-common.h | 7 +++++++ 1 file changed, 7 insertions(+) diff --git a/include/qemu-common.h b/include/qemu-common.h index f8622141a8..644b46dcdd 100644 --- a/include/qemu-common.h +++ b/include/qemu-common.h @@ -370,6 +370,12 @@ static inline uint8_t from_bcd(uint8_t val) } /* compute with 96 bit intermediate result: (a*b)/c */ +#ifdef CONFIG_INT128 +static inline uint64_t muldiv64(uint64_t a, uint32_t b, uint32_t c) +{ + return (__int128_t)a * b / c; +} +#else static inline uint64_t muldiv64(uint64_t a, uint32_t b, uint32_t c) { union { @@ -392,6 +398,7 @@ static inline uint64_t muldiv64(uint64_t a, uint32_t b, uint32_t c) res.l.low = (((rh % c) << 32) + (rl & 0xffffffff)) / c; return res.ll; } +#endif /* Round number down to multiple */ #define QEMU_ALIGN_DOWN(n, m) ((n) / (m) * (m))