Avoid switching between scalar and SIMD in Affine_vpts.
This might avoid a scenario where math works out differently
between skvx and scalar.
Change-Id: If5561fc451d27114a79f7d12d3bee381719c1db3
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/638222
Commit-Queue: Michael Ludwig <michaelludwig@google.com>
Reviewed-by: Michael Ludwig <michaelludwig@google.com>
Auto-Submit: John Stiles <johnstiles@google.com>
diff --git a/src/core/SkMatrix.cpp b/src/core/SkMatrix.cpp
index d304da0..50c6e7a 100644
--- a/src/core/SkMatrix.cpp
+++ b/src/core/SkMatrix.cpp
@@ -987,16 +987,20 @@
skvx::float4 skew4(kx, ky, kx, ky); // applied to swizzle of src4
bool trailingElement = (count & 1);
count >>= 1;
+ skvx::float4 src4;
for (int i = 0; i < count; ++i) {
- skvx::float4 src4 = skvx::float4::Load(src);
+ src4 = skvx::float4::Load(src);
skvx::float4 swz4 = skvx::shuffle<1,0,3,2>(src4); // y0 x0, y1 x1
(src4 * scale4 + swz4 * skew4 + trans4).store(dst);
src += 2;
dst += 2;
}
if (trailingElement) {
- dst->set(src->fX * sx + src->fY * kx + tx,
- src->fX * ky + src->fY * sy + ty);
+ // We use the same logic here to ensure that the math stays consistent throughout, even
+ // though the high float2 is ignored.
+ src4.lo = skvx::float2::Load(src);
+ skvx::float4 swz4 = skvx::shuffle<1,0,3,2>(src4); // y0 x0, y1 x1
+ (src4 * scale4 + swz4 * skew4 + trans4).lo.store(dst);
}
}
}
