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QuantizeBlock SSE2 Optimization:

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Another store to load forward block was detected coming from the function
FTransform.
FTransform save the output data 4 times 8 bytes each. when this data is
later being loaded by the QuantizeBlock function in one chunk of 16 bytes
that caused a store to load forward block.
The fix was done in the FTransform function where each two consecutive 8 bytes
were merged into one 16 bytes register and saved into the memory.
This fix gives ~21% function level gain and 1.6% user level gain.

Change-Id: Idc27c307d5083f3ebe206d3ca19059e5bd465992
This commit is contained in:
levytamar82 2014-06-18 04:45:51 -07:00 committed by James Zern
parent 2bc0dc3edc
commit 27bfeee43a
1 changed files with 4 additions and 4 deletions
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8
src/dsp/enc_sse2.c
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@ -445,10 +445,10 @@ static void FTransform(const uint8_t* src, const uint8_t* ref, int16_t* out) {
// -> f1 = f1 + 1 - (a3 == 0)
const __m128i g1 = _mm_add_epi16(f1, _mm_cmpeq_epi16(a32, zero));
_mm_storel_epi64((__m128i*)&out[ 0], d0);
_mm_storel_epi64((__m128i*)&out[ 4], g1);
_mm_storel_epi64((__m128i*)&out[ 8], d2);
_mm_storel_epi64((__m128i*)&out[12], f3);
const __m128i d0_g1 = _mm_unpacklo_epi64(d0, g1);
const __m128i d2_f3 = _mm_unpacklo_epi64(d2, f3);
_mm_storeu_si128((__m128i*)&out[0], d0_g1);
_mm_storeu_si128((__m128i*)&out[8], d2_f3);
}
}