Use aligned operations for solid SourceOver operations.

Aligned load() and store() have been shown to be faster for the
composition functions. This patch applies this to the solid
SourceOver function.

Reviewed-by: Samuel Rødal

1 files changed, 5 insertions, 2 deletions

diff --git a/src/gui/painting/qdrawhelper_sse2.cpp b/src/gui/painting/qdrawhelper_sse2.cpp
index ac73958..f97d865 100644
--- a/src/gui/painting/qdrawhelper_sse2.cpp
+++ b/src/gui/painting/qdrawhelper_sse2.cpp
@@ -300,11 +300,14 @@ void QT_FASTCALL comp_func_solid_SourceOver_sse2(uint *destPixels, int length, u
         const __m128i half = _mm_set1_epi16(0x80);
         const __m128i minusAlphaOfColorVector = _mm_set1_epi16(minusAlphaOfColor);
 
+        ALIGNMENT_PROLOGUE_16BYTES(dst, x, length)
+            destPixels[x] = color + BYTE_MUL(destPixels[x], minusAlphaOfColor);
+
         for (; x < length-3; x += 4) {
-            __m128i dstVector = _mm_loadu_si128((__m128i *)&dst[x]);
+            __m128i dstVector = _mm_load_si128((__m128i *)&dst[x]);
             BYTE_MUL_SSE2(dstVector, dstVector, minusAlphaOfColorVector, colorMask, half);
             dstVector = _mm_add_epi8(colorVector, dstVector);
-            _mm_storeu_si128((__m128i *)&dst[x], dstVector);
+            _mm_store_si128((__m128i *)&dst[x], dstVector);
         }
         for (;x < length; ++x)
             destPixels[x] = color + BYTE_MUL(destPixels[x], minusAlphaOfColor);