Commit 340e6b01 authored by Andreas Rheinhardt's avatar Andreas Rheinhardt Committed by Michael Niedermayer

avcodec/adxdec: Remove unnecessary left-shift

Replace "(a * (1 << shift) * b + c) >> shift" by "a * b + (c >> shift)".
It is equivalent to the old code because a is in the range of uint16_t,
shift is 12 and b is effectively a signed 4-bit number, so that no
overflow/truncation of high bits happens during the multiplication
(overflow would be undefined anyway).
Signed-off-by: 's avatarAndreas Rheinhardt <andreas.rheinhardt@gmail.com>
Signed-off-by: 's avatarMichael Niedermayer <michael@niedermayer.cc>
parent 59a9d65e
...@@ -81,7 +81,7 @@ static int adx_decode(ADXContext *c, int16_t *out, int offset, ...@@ -81,7 +81,7 @@ static int adx_decode(ADXContext *c, int16_t *out, int offset,
s2 = prev->s2; s2 = prev->s2;
for (i = 0; i < BLOCK_SAMPLES; i++) { for (i = 0; i < BLOCK_SAMPLES; i++) {
d = get_sbits(&gb, 4); d = get_sbits(&gb, 4);
s0 = ((d * (1 << COEFF_BITS)) * scale + c->coeff[0] * s1 + c->coeff[1] * s2) >> COEFF_BITS; s0 = d * scale + ((c->coeff[0] * s1 + c->coeff[1] * s2) >> COEFF_BITS);
s2 = s1; s2 = s1;
s1 = av_clip_int16(s0); s1 = av_clip_int16(s0);
*out++ = s1; *out++ = s1;
......
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