Tighten the workaround for B5G6R5 on Intel drivers

This driver bug has been fixed in 20.19.15.4539.

BUG=chromium:644610
TEST=dEQP-GLES3.functional.fbo.blit.default_framebuffer.rgb565*

Change-Id: I37556304ed4f70771fb88b792c01b6be5b3aa294
Reviewed-on: https://chromium-review.googlesource.com/424103
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Commit-Queue: Jamie Madill <jmadill@chromium.org>

include/platform/WorkaroundsD3D.h

@@ -83,7 +83,7 @@ struct WorkaroundsD3D
 
     // In Intel driver, the data with format DXGI_FORMAT_B5G6R5_UNORM will be parsed incorrectly.
     // This workaroud will disable B5G6R5 support when it's Intel driver. By default, it will use
-    // R8G8B8A8 format.
+    // R8G8B8A8 format. This bug is fixed in version 4539 on Intel drivers.
     bool disableB5G6R5Support = false;
 
     // On some Intel drivers, evaluating unary minus operator on integer may get wrong answer in

src/libANGLE/renderer/d3d/d3d11/renderer11_utils.cpp

@@ -980,6 +980,18 @@ size_t GetMaximumStreamOutputSeparateComponents(D3D_FEATURE_LEVEL featureLevel)
     }
 }
 
+IntelDriverVersion GetIntelDriverVersion(const Optional<LARGE_INTEGER> driverVersion)
+{
+    if (!driverVersion.valid())
+        return IntelDriverVersion(0);
+
+    // According to http://www.intel.com/content/www/us/en/support/graphics-drivers/000005654.html,
+    // only the fourth part is necessary since it stands for the driver specific unique version
+    // number.
+    WORD part = LOWORD(driverVersion.value().LowPart);
+    return IntelDriverVersion(part);
+}
+
 }  // anonymous namespace
 
 unsigned int GetReservedVertexUniformVectors(D3D_FEATURE_LEVEL featureLevel)
@@ -1853,28 +1865,22 @@ angle::WorkaroundsD3D GenerateWorkarounds(const Renderer11DeviceCaps &deviceCaps
     workarounds.flushAfterEndingTransformFeedback = IsNvidia(adapterDesc.VendorId);
     workarounds.getDimensionsIgnoresBaseLevel     = IsNvidia(adapterDesc.VendorId);
 
-    workarounds.preAddTexelFetchOffsets = IsIntel(adapterDesc.VendorId);
-    workarounds.disableB5G6R5Support    = IsIntel(adapterDesc.VendorId);
+    if (IsIntel(adapterDesc.VendorId))
+    {
+        workarounds.preAddTexelFetchOffsets           = true;
+        workarounds.useSystemMemoryForConstantBuffers = true;
+        workarounds.disableB5G6R5Support =
+            d3d11_gl::GetIntelDriverVersion(deviceCaps.driverVersion) < IntelDriverVersion(4539);
+        if (IsSkylake(adapterDesc.DeviceId))
+        {
+            workarounds.callClearTwiceOnSmallTarget = true;
+            workarounds.emulateIsnanFloat =
+                d3d11_gl::GetIntelDriverVersion(deviceCaps.driverVersion) <
+                IntelDriverVersion(4542);
+        }
         workarounds.rewriteUnaryMinusOperator =
-        IsIntel(adapterDesc.VendorId) &&
-        (IsBroadwell(adapterDesc.DeviceId) || IsHaswell(adapterDesc.DeviceId));
-    if (IsIntel(adapterDesc.VendorId) && IsSkylake(adapterDesc.DeviceId))
-    {
-        if (deviceCaps.driverVersion.valid())
-        {
-            WORD part1 = HIWORD(deviceCaps.driverVersion.value().LowPart);
-            WORD part2 = LOWORD(deviceCaps.driverVersion.value().LowPart);
-
-            // Disable the workaround on the new fixed driver.
-            workarounds.emulateIsnanFloat = part1 <= 16u && part2 < 4542u;
+            IsBroadwell(adapterDesc.DeviceId) || IsHaswell(adapterDesc.DeviceId);
     }
-        else
-        {
-            workarounds.emulateIsnanFloat = true;
-        }
-    }
-    workarounds.callClearTwiceOnSmallTarget =
-        IsIntel(adapterDesc.VendorId) && IsSkylake(adapterDesc.DeviceId);
 
     // TODO(jmadill): Disable when we have a fixed driver version.
     workarounds.emulateTinyStencilTextures = IsAMD(adapterDesc.VendorId);
@@ -1888,8 +1894,6 @@ angle::WorkaroundsD3D GenerateWorkarounds(const Renderer11DeviceCaps &deviceCaps
         workarounds.emulateTinyStencilTextures = false;
     }
 
-    workarounds.useSystemMemoryForConstantBuffers = IsIntel(adapterDesc.VendorId);
-
     // Call platform hooks for testing overrides.
     ANGLEPlatformCurrent()->overrideWorkaroundsD3D(&workarounds);
 

src/libANGLE/renderer/driver_utils.cpp

@@ -47,6 +47,45 @@ const uint32_t Kabylake[] = {0x5916, 0x5913, 0x5906, 0x5926, 0x5921, 0x5915, 0x5
 
 }  // anonymous namespace
 
+IntelDriverVersion::IntelDriverVersion(uint16_t lastPart) : mVersionPart(lastPart)
+{
+}
+
+bool IntelDriverVersion::operator==(const IntelDriverVersion &version)
+{
+    return mVersionPart == version.mVersionPart;
+}
+
+bool IntelDriverVersion::operator!=(const IntelDriverVersion &version)
+{
+    return !(*this == version);
+}
+
+bool IntelDriverVersion::operator<(const IntelDriverVersion &version)
+{
+    // See http://www.intel.com/content/www/us/en/support/graphics-drivers/000005654.html to
+    // understand the Intel graphics driver version number on Windows.
+    // mVersionPart1 changes with OS version. mVersionPart2 changes with DirectX version.
+    // mVersionPart3 stands for release year. mVersionPart4 is driver specific unique version
+    // number.
+    // For example: Intel driver version '20.19.15.4539'
+    //              20   -> windows 10 driver
+    //              19   -> DirectX 12 first version(12.0) supported
+    //              15   -> Driver released in 2015
+    //              4539 -> Driver specific unique version number
+    // For linux, Intel graphics driver version is the mesa version. The version number has three
+    // parts: major revision, minor revision, release number. So, for linux, we need to compare
+    // three parts.
+    // Currently, it's only used in windows. So, checking the last part is enough. Once it's needed
+    // in other platforms, it's easy to be extended.
+    return mVersionPart < version.mVersionPart;
+}
+
+bool IntelDriverVersion::operator>=(const IntelDriverVersion &version)
+{
+    return !(*this < version);
+}
+
 bool IsHaswell(uint32_t DeviceId)
 {
     return std::find(std::begin(Haswell), std::end(Haswell), DeviceId) != std::end(Haswell);

src/libANGLE/renderer/driver_utils.h

@@ -46,6 +46,22 @@ inline bool IsQualcomm(uint32_t vendor_id)
 }
 
 // Intel
+class IntelDriverVersion
+{
+  public:
+    // Currently, We only provide the constructor with one parameter. It mainly used in Intel
+    // version number on windows. If you want to use this class on other platforms, it's easy to
+    // be extended.
+    IntelDriverVersion(uint16_t lastPart);
+    bool operator==(const IntelDriverVersion &);
+    bool operator!=(const IntelDriverVersion &);
+    bool operator<(const IntelDriverVersion &);
+    bool operator>=(const IntelDriverVersion &);
+
+  private:
+    uint16_t mVersionPart;
+};
+
 bool IsHaswell(uint32_t DeviceId);
 bool IsBroadwell(uint32_t DeviceId);
 bool IsCherryView(uint32_t DeviceId);