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| author | Petar Jovanovic <petar.jovanovic@imgtec.com> | 2013-05-23 19:37:53 +0200 |
|---|---|---|
| committer | Aurelien Jarno <aurelien@aurel32.net> | 2013-07-28 18:26:36 +0200 |
| commit | 4877866ee4fbd760c943577bb6d1eba489fb6c6e (patch) | |
| tree | e90c5764a969b376b2a420a1a974c966ffe6516d /target-mips | |
| parent | 200a06397f5d3e982028fd78b25b420507ade021 (diff) | |
| download | qemu-4877866ee4fbd760c943577bb6d1eba489fb6c6e.tar.gz | |
target-mips: fix multiplication in mipsdsp_rndq15_mul_q15_q15
Multiplication of Q15 fractional halfword vectors was incorrect in the
previous implementation of mipsdsp_rndq15_mul_q15_q15. It failed to take
element signs into account. This change fixes it, and it adds a test case
for it.
The change also removes unnecessary cast in the function
mipsdsp_mul_q15_q15_overflowflag21().
Signed-off-by: Petar Jovanovic <petar.jovanovic@imgtec.com>
Reviewed-by: Richard Henderson <rth@twiddle.net>
Signed-off-by: Aurelien Jarno <aurelien@aurel32.net>
Diffstat (limited to 'target-mips')
| -rw-r--r-- | target-mips/dsp_helper.c | 4 |
1 files changed, 2 insertions, 2 deletions
diff --git a/target-mips/dsp_helper.c b/target-mips/dsp_helper.c index 4116de93c3..c718a786e1 100644 --- a/target-mips/dsp_helper.c +++ b/target-mips/dsp_helper.c @@ -390,7 +390,7 @@ static inline int32_t mipsdsp_mul_q15_q15_overflowflag21(uint16_t a, uint16_t b, temp = 0x7FFFFFFF; set_DSPControl_overflow_flag(1, 21, env); } else { - temp = ((int32_t)(int16_t)a * (int32_t)(int16_t)b) << 1; + temp = ((int16_t)a * (int16_t)b) << 1; } return temp; @@ -622,7 +622,7 @@ static inline int16_t mipsdsp_rndq15_mul_q15_q15(uint16_t a, uint16_t b, temp = 0x7FFF0000; set_DSPControl_overflow_flag(1, 21, env); } else { - temp = (a * b) << 1; + temp = ((int16_t)a * (int16_t)b) << 1; temp = temp + 0x00008000; } |