From: Jan Zielinski <jan.zielinski@intel.com>
Date: Tue, 23 Jul 2019 10:47:28 +0000 (+0200)
Subject: swr/rasterizer: Fix 3D resource copies.
X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=3d6cffffcf41349ff5db332a4662adb49d842a3a;p=mesa.git

swr/rasterizer: Fix 3D resource copies.

Ensure constant attributes stay constant with barycentric interpolation.

Reviewed-by: Alok Hota <alok.hota@intel.com>
---

diff --git a/src/gallium/drivers/swr/rasterizer/common/simdintrin.h b/src/gallium/drivers/swr/rasterizer/common/simdintrin.h
index 4145ba8dcce..df5c3ac6056 100644
--- a/src/gallium/drivers/swr/rasterizer/common/simdintrin.h
+++ b/src/gallium/drivers/swr/rasterizer/common/simdintrin.h
@@ -282,6 +282,13 @@ static SIMDINLINE simdscalar InterpolateComponent(simdscalar const& vI,
     const float* pInterpB = &pInterpBuffer[Attrib * 3 * numComponents + numComponents + Comp];
     const float* pInterpC = &pInterpBuffer[Attrib * 3 * numComponents + numComponents * 2 + Comp];
 
+    if ((pInterpA[0] == pInterpB[0]) && (pInterpA[0] == pInterpC[0]))
+    {
+        // Ensure constant attribs are constant.  Required for proper
+        // 3D resource copies.
+        return _simd_broadcast_ss(pInterpA);
+    }
+
     simdscalar vA = _simd_broadcast_ss(pInterpA);
     simdscalar vB = _simd_broadcast_ss(pInterpB);
     simdscalar vC = _simd_broadcast_ss(pInterpC);
@@ -332,6 +339,13 @@ static SIMDINLINE simd4scalar InterpolateComponent(simd4scalar const& vI,
     const float* pInterpB = &pInterpBuffer[Attrib * 3 * numComponents + numComponents + Comp];
     const float* pInterpC = &pInterpBuffer[Attrib * 3 * numComponents + numComponents * 2 + Comp];
 
+    if ((pInterpA[0] == pInterpB[0]) && (pInterpA[0] == pInterpC[0]))
+    {
+        // Ensure constant attribs are constant.  Required for proper
+        // 3D resource copies.
+        return SIMD128::broadcast_ss(pInterpA);
+    }
+
     simd4scalar vA = SIMD128::broadcast_ss(pInterpA);
     simd4scalar vB = SIMD128::broadcast_ss(pInterpB);
     simd4scalar vC = SIMD128::broadcast_ss(pInterpC);