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simplify the fwd transform

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-> remove two shifts

Change-Id: Ibc55bca98588da30553a7870224ffd0e13d57f52
This commit is contained in:
skal
2012-11-15 09:51:35 +01:00
parent b542611964
commit 42c3b550ba
3 changed files with 60 additions and 60 deletions
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52
src/dsp/enc_sse2.c
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@ -295,8 +295,8 @@ static void FTransformSSE2(const uint8_t* src, const uint8_t* ref,
int16_t* out) {
const __m128i zero = _mm_setzero_si128();
const __m128i seven = _mm_set1_epi16(7);
const __m128i k7500 = _mm_set1_epi32(7500);
const __m128i k14500 = _mm_set1_epi32(14500);
const __m128i k937 = _mm_set1_epi32(937);
const __m128i k1812 = _mm_set1_epi32(1812);
const __m128i k51000 = _mm_set1_epi32(51000);
const __m128i k12000_plus_one = _mm_set1_epi32(12000 + (1 << 16));
const __m128i k5352_2217 = _mm_set_epi16(5352, 2217, 5352, 2217,
@ -352,32 +352,32 @@ static void FTransformSSE2(const uint8_t* src, const uint8_t* ref,
// First pass and subsequent transpose.
{
// Same operations are done on the (0,3) and (1,2) pairs.
// b0 = (a0 + a3) << 3
// b1 = (a1 + a2) << 3
// b3 = (a0 - a3) << 3
// b2 = (a1 - a2) << 3
// b0 = (a0 + a3)
// b1 = (a1 + a2)
// b3 = (a0 - a3)
// b2 = (a1 - a2)
const __m128i a01 = _mm_add_epi16(v01, v32);
const __m128i a32 = _mm_sub_epi16(v01, v32);
const __m128i b01 = _mm_slli_epi16(a01, 3);
const __m128i b32 = _mm_slli_epi16(a32, 3);
const __m128i b11 = _mm_unpackhi_epi64(b01, b01);
const __m128i b22 = _mm_unpackhi_epi64(b32, b32);
const __m128i b11 = _mm_unpackhi_epi64(a01, a01);
const __m128i b22 = _mm_unpackhi_epi64(a32, a32);
// e0 = b0 + b1
// e2 = b0 - b1
const __m128i e0 = _mm_add_epi16(b01, b11);
const __m128i e2 = _mm_sub_epi16(b01, b11);
const __m128i e02 = _mm_unpacklo_epi64(e0, e2);
// e0 = (b0 + b1)
// e2 = (b0 - b1)
const __m128i e0 = _mm_add_epi16(a01, b11);
const __m128i e2 = _mm_sub_epi16(a01, b11);
// e02 = [e0 | e2] << 3
const __m128i e0_e2 = _mm_unpacklo_epi64(e0, e2);
const __m128i e02 = _mm_slli_epi16(e0_e2, 3);
// e1 = (b3 * 5352 + b2 * 2217 + 14500) >> 12
// e3 = (b3 * 2217 - b2 * 5352 + 7500) >> 12
const __m128i b23 = _mm_unpacklo_epi16(b22, b32);
// e1 = (b3 * 5352 + b2 * 2217 + 1812) >> 9
// e3 = (b3 * 2217 - b2 * 5352 + 937) >> 9
const __m128i b23 = _mm_unpacklo_epi16(b22, a32);
const __m128i c1 = _mm_madd_epi16(b23, k5352_2217);
const __m128i c3 = _mm_madd_epi16(b23, k2217_5352);
const __m128i d1 = _mm_add_epi32(c1, k14500);
const __m128i d3 = _mm_add_epi32(c3, k7500);
const __m128i e1 = _mm_srai_epi32(d1, 12);
const __m128i e3 = _mm_srai_epi32(d3, 12);
const __m128i d1 = _mm_add_epi32(c1, k1812);
const __m128i d3 = _mm_add_epi32(c3, k937);
const __m128i e1 = _mm_srai_epi32(d1, 9);
const __m128i e3 = _mm_srai_epi32(d3, 9);
const __m128i e13 = _mm_packs_epi32(e1, e3);
// Transpose.
@ -406,13 +406,12 @@ static void FTransformSSE2(const uint8_t* src, const uint8_t* ref,
const __m128i a32 = _mm_sub_epi16(v01, v32);
const __m128i a11 = _mm_unpackhi_epi64(a01, a01);
const __m128i a22 = _mm_unpackhi_epi64(a32, a32);
const __m128i a01_plus_7 = _mm_add_epi16(a01, seven);
// d0 = (a0 + a1 + 7) >> 4;
// d2 = (a0 - a1 + 7) >> 4;
const __m128i b0 = _mm_add_epi16(a01, a11);
const __m128i b2 = _mm_sub_epi16(a01, a11);
const __m128i c0 = _mm_add_epi16(b0, seven);
const __m128i c2 = _mm_add_epi16(b2, seven);
const __m128i c0 = _mm_add_epi16(a01_plus_7, a11);
const __m128i c2 = _mm_sub_epi16(a01_plus_7, a11);
const __m128i d0 = _mm_srai_epi16(c0, 4);
const __m128i d2 = _mm_srai_epi16(c2, 4);
@ -430,6 +429,7 @@ static void FTransformSSE2(const uint8_t* src, const uint8_t* ref,
// f1 = f1 + (a3 != 0);
// The compare will return (0xffff, 0) for (==0, !=0). To turn that into the
// desired (0, 1), we add one earlier through k12000_plus_one.
// -> f1 = f1 + 1 - (a3 == 0)
const __m128i g1 = _mm_add_epi16(f1, _mm_cmpeq_epi16(a32, zero));
_mm_storel_epi64((__m128i*)&out[ 0], d0);