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Change: Reduce number of instructions in AlphaBlendTwoPixels

pull/10027/head
Jonathan G Rennison 2022-09-29 08:47:10 +01:00 committed by Loïc Guilloux
parent f9cdb5b610
commit 47456ac672
1 changed files with 2 additions and 4 deletions
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6
src/blitter/32bpp_sse_func.hpp
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@ -66,8 +66,7 @@ static inline __m128i DistributeAlpha(const __m128i from, const __m128i &mask)
#if (SSE_VERSION == 2)
__m128i alphaAB = _mm_shufflelo_epi16(from, 0x3F); // PSHUFLW, put alpha1 in front of each rgb1
alphaAB = _mm_shufflehi_epi16(alphaAB, 0x3F); // PSHUFHW, put alpha2 in front of each rgb2
alphaAB = _mm_or_si128(alphaAB, mask); // POR, set alpha fields to all 1
return _mm_xor_si128(alphaAB, mask); // PXOR, set alpha fields to 0
return _mm_andnot_si128(mask, alphaAB); // PANDN, set alpha fields to 0
#else
return _mm_shuffle_epi8(from, mask);
#endif
@ -80,8 +79,7 @@ static inline __m128i AlphaBlendTwoPixels(__m128i src, __m128i dst, const __m128
__m128i dstAB = _mm_unpacklo_epi8(dst, _mm_setzero_si128());
__m128i alphaMaskAB = _mm_cmpgt_epi16(srcAB, _mm_setzero_si128()); // PCMPGTW (alpha > 0) ? 0xFFFF : 0
__m128i alphaAB = _mm_srli_epi16(alphaMaskAB, 15);
alphaAB = _mm_add_epi16(alphaAB, srcAB); // if (alpha > 0) a++;
__m128i alphaAB = _mm_sub_epi16(srcAB, alphaMaskAB); // if (alpha > 0) a++;
alphaAB = DistributeAlpha(alphaAB, distribution_mask);
srcAB = _mm_sub_epi16(srcAB, dstAB); // PSUBW, (r - Cr)