AuroraMiddleware/skia2
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Don't do a pointless << 0.

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It's very common (universal?) that alpha is the top byte.
You'd hope the compiler would remove the left shift then,
but I've seen Clang just do a dumb left shift of zero. :(

BUG=skia:

Review URL: https://codereview.chromium.org/872243003
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mtklein 2015-01-26 07:07:03 -08:00 committed by Commit bot
parent 65327efb5b
commit 8d029a4ebe
1 changed files with 4 additions and 0 deletions
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4
src/opts/SkColor_opts_SSE2.h
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@ -81,8 +81,12 @@ static inline __m128i SkAlphaMulQ_SSE2(const __m128i& c, const unsigned scale) {
}
static inline __m128i SkGetPackedA32_SSE2(const __m128i& src) {
#if SK_A32_SHIFT == 24 // It's very common (universal?) that alpha is the top byte.
return _mm_srli_epi32(src, 24); // You'd hope the compiler would remove the left shift then,
#else // but I've seen Clang just do a dumb left shift of zero. :(
__m128i a = _mm_slli_epi32(src, (24 - SK_A32_SHIFT));
return _mm_srli_epi32(a, 24);
#endif
}
static inline __m128i SkGetPackedR32_SSE2(const __m128i& src) {