From e8407590dcd8432d77dbe5a54dd3b0328484f7ea Mon Sep 17 00:00:00 2001
From: Ashley Hale <ahale@mozilla.com>
Date: Wed, 1 Mar 2023 18:03:04 -0800
Subject: [PATCH] Disable ClearView with scissor on Skylake iGPU because of
 observed bugs with edge corruption. (#27)

---
 include/platform/autogen/FeaturesD3D_autogen.h       | 6 ++++++
 include/platform/d3d_features.json                   | 8 ++++++++
 src/libANGLE/renderer/d3d/d3d11/Clear11.cpp          | 5 +++++
 src/libANGLE/renderer/d3d/d3d11/renderer11_utils.cpp | 4 ++++
 util/autogen/angle_features_autogen.cpp              | 1 +
 util/autogen/angle_features_autogen.h                | 1 +
 6 files changed, 25 insertions(+)

diff --git a/include/platform/autogen/FeaturesD3D_autogen.h b/include/platform/autogen/FeaturesD3D_autogen.h
index 0dd1015cbe..271a40eab7 100644
--- a/include/platform/autogen/FeaturesD3D_autogen.h
+++ b/include/platform/autogen/FeaturesD3D_autogen.h
@@ -116,6 +116,12 @@ struct FeaturesD3D : FeatureSetBase
         &members,
     };
 
+    FeatureInfo scissoredClearArtifacts = {
+        "scissoredClearArtifacts",
+        FeatureCategory::D3DWorkarounds,
+        &members,
+    };
+
     FeatureInfo useSystemMemoryForConstantBuffers = {
         "useSystemMemoryForConstantBuffers",
         FeatureCategory::D3DWorkarounds,
diff --git a/include/platform/d3d_features.json b/include/platform/d3d_features.json
index 941918c8d0..daebb529fc 100644
--- a/include/platform/d3d_features.json
+++ b/include/platform/d3d_features.json
@@ -128,6 +128,14 @@
             ],
             "issue": "https://bugzilla.mozilla.org/show_bug.cgi?id=1633628"
         },
+        {
+            "name": "scissored_clear_artifacts",
+            "category": "Workarounds",
+            "description": [
+                "On Skylake, calling ClearView with a scissor rect that is not a multiple of 8x4 pixels causes corruption of pixels in the 8x4 pixel tiles along the edge which resembles a square wave"
+            ],
+            "issue": "https://bugzilla.mozilla.org/show_bug.cgi?id=1817240"
+        },
         {
             "name": "use_system_memory_for_constant_buffers",
             "category": "Workarounds",
diff --git a/src/libANGLE/renderer/d3d/d3d11/Clear11.cpp b/src/libANGLE/renderer/d3d/d3d11/Clear11.cpp
index 764349c3d0..ccedcf99d3 100644
--- a/src/libANGLE/renderer/d3d/d3d11/Clear11.cpp
+++ b/src/libANGLE/renderer/d3d/d3d11/Clear11.cpp
@@ -510,6 +510,11 @@ angle::Result Clear11::clearFramebuffer(const gl::Context *context,
             }
         }
 
+        if (needScissoredClear && mRenderer->getFeatures().scissoredClearArtifacts.enabled)
+        {
+            canClearView = false;
+        }
+
         if ((!canClearView && needScissoredClear) || clearParams.colorType != GL_FLOAT ||
             (formatInfo.redBits > 0 && !r) || (formatInfo.greenBits > 0 && !g) ||
             (formatInfo.blueBits > 0 && !b) || (formatInfo.alphaBits > 0 && !a))
diff --git a/src/libANGLE/renderer/d3d/d3d11/renderer11_utils.cpp b/src/libANGLE/renderer/d3d/d3d11/renderer11_utils.cpp
index af7969dcf0..f410161ff6 100644
--- a/src/libANGLE/renderer/d3d/d3d11/renderer11_utils.cpp
+++ b/src/libANGLE/renderer/d3d/d3d11/renderer11_utils.cpp
@@ -2467,6 +2467,10 @@ void InitializeFeatures(const Renderer11DeviceCaps &deviceCaps,
     ANGLE_FEATURE_CONDITION(features, preAddTexelFetchOffsets, isIntel);
     ANGLE_FEATURE_CONDITION(features, useSystemMemoryForConstantBuffers, isIntel);
 
+    // ClearView on Skylake seems to incorrectly clear with unaligned rects (edge has saw tooth
+    // pattern instead of straight).
+    ANGLE_FEATURE_CONDITION(features, scissoredClearArtifacts, isIntel && isSkylake);
+
     ANGLE_FEATURE_CONDITION(features, callClearTwice,
                             isIntel && isSkylake && capsVersion >= angle::VersionTriple(16, 0, 0) &&
                                 capsVersion < angle::VersionTriple(16, 4771, 0));
diff --git a/util/autogen/angle_features_autogen.cpp b/util/autogen/angle_features_autogen.cpp
index 49e00dcb3a..47958dd246 100644
--- a/util/autogen/angle_features_autogen.cpp
+++ b/util/autogen/angle_features_autogen.cpp
@@ -305,6 +305,7 @@ constexpr PackedEnumMap<Feature, const char *> kFeatureNames = {{
     {Feature::RoundOutputAfterDithering, "roundOutputAfterDithering"},
     {Feature::SanitizeAMDGPURendererString, "sanitizeAMDGPURendererString"},
     {Feature::ScalarizeVecAndMatConstructorArgs, "scalarizeVecAndMatConstructorArgs"},
+    {Feature::ScissoredClearArtifacts, "scissoredClearArtifacts"},
     {Feature::SelectViewInGeometryShader, "selectViewInGeometryShader"},
     {Feature::SetDataFasterThanImageUpload, "setDataFasterThanImageUpload"},
     {Feature::SetDataFasterThanImageUploadOn128bitFormats, "setDataFasterThanImageUploadOn128bitFormats"},
diff --git a/util/autogen/angle_features_autogen.h b/util/autogen/angle_features_autogen.h
index e916dc0807..74b0fc4cbc 100644
--- a/util/autogen/angle_features_autogen.h
+++ b/util/autogen/angle_features_autogen.h
@@ -305,6 +305,7 @@ enum class Feature
     RoundOutputAfterDithering,
     SanitizeAMDGPURendererString,
     ScalarizeVecAndMatConstructorArgs,
+    ScissoredClearArtifacts,
     SelectViewInGeometryShader,
     SetDataFasterThanImageUpload,
     SetDataFasterThanImageUploadOn128bitFormats,
-- 
2.54.0