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| author | Luis Pires <luis.pires@eldorado.org.br> | 2021-10-25 16:11:38 -0300 |
|---|---|---|
| committer | Richard Henderson <richard.henderson@linaro.org> | 2021-10-27 17:10:00 -0700 |
| commit | 40f3e79a862554553811d0681c05e00a4705e91c (patch) | |
| tree | 4fc15b4a02f1d6354a28486c6f91d9fc1dd0f1aa /include/qemu | |
| parent | 8ac2d6c526d9ea0c89c8aa7046ca56e1b1b9d130 (diff) | |
| download | qemu-40f3e79a862554553811d0681c05e00a4705e91c.zip qemu-40f3e79a862554553811d0681c05e00a4705e91c.tar.gz qemu-40f3e79a862554553811d0681c05e00a4705e91c.tar.bz2 | |
host-utils: add 128-bit quotient support to divu128/divs128
These will be used to implement new decimal floating point
instructions from Power ISA 3.1.
The remainder is now returned directly by divu128/divs128,
freeing up phigh to receive the high 64 bits of the quotient.
Signed-off-by: Luis Pires <luis.pires@eldorado.org.br>
Reviewed-by: Richard Henderson <richard.henderson@linaro.org>
Message-Id: <20211025191154.350831-4-luis.pires@eldorado.org.br>
Signed-off-by: Richard Henderson <richard.henderson@linaro.org>
Diffstat (limited to 'include/qemu')
| -rw-r--r-- | include/qemu/host-utils.h | 20 |
1 files changed, 13 insertions, 7 deletions
diff --git a/include/qemu/host-utils.h b/include/qemu/host-utils.h index 08a17e1..a3a7ced7 100644 --- a/include/qemu/host-utils.h +++ b/include/qemu/host-utils.h @@ -56,26 +56,32 @@ static inline uint64_t muldiv64(uint64_t a, uint32_t b, uint32_t c) return (__int128_t)a * b / c; } -static inline void divu128(uint64_t *plow, uint64_t *phigh, uint64_t divisor) +static inline uint64_t divu128(uint64_t *plow, uint64_t *phigh, + uint64_t divisor) { __uint128_t dividend = ((__uint128_t)*phigh << 64) | *plow; __uint128_t result = dividend / divisor; + *plow = result; - *phigh = dividend % divisor; + *phigh = result >> 64; + return dividend % divisor; } -static inline void divs128(int64_t *plow, int64_t *phigh, int64_t divisor) +static inline int64_t divs128(uint64_t *plow, int64_t *phigh, + int64_t divisor) { - __int128_t dividend = ((__int128_t)*phigh << 64) | (uint64_t)*plow; + __int128_t dividend = ((__int128_t)*phigh << 64) | *plow; __int128_t result = dividend / divisor; + *plow = result; - *phigh = dividend % divisor; + *phigh = result >> 64; + return dividend % divisor; } #else void muls64(uint64_t *plow, uint64_t *phigh, int64_t a, int64_t b); void mulu64(uint64_t *plow, uint64_t *phigh, uint64_t a, uint64_t b); -void divu128(uint64_t *plow, uint64_t *phigh, uint64_t divisor); -void divs128(int64_t *plow, int64_t *phigh, int64_t divisor); +uint64_t divu128(uint64_t *plow, uint64_t *phigh, uint64_t divisor); +int64_t divs128(uint64_t *plow, int64_t *phigh, int64_t divisor); static inline uint64_t muldiv64(uint64_t a, uint32_t b, uint32_t c) { |