Allow small compressed mip level copies

src/libANGLE/validationES.cpp

@@ -2965,16 +2965,15 @@ bool ValidateCompressedRegion(const Context *context,
                               GLsizei width,
                               GLsizei height)
 {
-    if (formatInfo.compressed)
+    ASSERT(formatInfo.compressed);
+
+    // INVALID_VALUE is generated if the image format is compressed and the dimensions of the
+    // subregion fail to meet the alignment constraints of the format.
+    if ((width % formatInfo.compressedBlockWidth != 0) ||
+        (height % formatInfo.compressedBlockHeight != 0))
     {
-        // INVALID_VALUE is generated if the image format is compressed and the dimensions of the
-        // subregion fail to meet the alignment constraints of the format.
-        if ((width % formatInfo.compressedBlockWidth != 0) ||
-            (height % formatInfo.compressedBlockHeight != 0))
-        {
-            context->validationError(GL_INVALID_VALUE, kInvalidCompressedRegionSize);
-            return false;
-        }
+        context->validationError(GL_INVALID_VALUE, kInvalidCompressedRegionSize);
+        return false;
     }
 
     return true;
@@ -3355,12 +3354,27 @@ bool ValidateCopyImageSubDataBase(const Context *context,
         return false;
     }
 
-    if (!ValidateCompressedRegion(context, srcFormatInfo, srcWidth, srcHeight))
+    bool fillsEntireMip               = false;
+    gl::Texture *dstTexture           = context->getTexture({dstName});
+    gl::TextureTarget dstTargetPacked = gl::PackParam<gl::TextureTarget>(dstTarget);
+    // TODO(http://anglebug.com/5643): Some targets (e.g., GL_TEXTURE_CUBE_MAP, GL_RENDERBUFFER) are
+    // unsupported when used with compressed formats due to gl::PackParam() returning
+    // TextureTarget::InvalidEnum.
+    if (dstTargetPacked != gl::TextureTarget::InvalidEnum)
+    {
+        const gl::Extents &dstExtents = dstTexture->getExtents(dstTargetPacked, dstLevel);
+        fillsEntireMip = dstX == 0 && dstY == 0 && dstZ == 0 && srcWidth == dstExtents.width &&
+                         srcHeight == dstExtents.height && srcDepth == dstExtents.depth;
+    }
+
+    if (srcFormatInfo.compressed && !fillsEntireMip &&
+        !ValidateCompressedRegion(context, srcFormatInfo, srcWidth, srcHeight))
     {
         return false;
     }
 
-    if (!ValidateCompressedRegion(context, dstFormatInfo, dstWidth, dstHeight))
+    if (dstFormatInfo.compressed && !fillsEntireMip &&
+        !ValidateCompressedRegion(context, dstFormatInfo, dstWidth, dstHeight))
     {
         return false;
     }

src/tests/gl_tests/TextureTest.cpp

@@ -3870,6 +3870,47 @@ TEST_P(Texture2DTestES3, CopyImage)
     EXPECT_PIXEL_RECT_EQ(0, 0, 2, 4, GLColor::red);
 }
 
+// Test GL_EXT_copy_image compressed texture copy with mipmaps smaller than the block size
+TEST_P(Texture2DTestES3, CopyCompressedImageMipMaps)
+{
+    ANGLE_SKIP_TEST_IF(!IsGLExtensionEnabled("GL_EXT_copy_image"));
+    // TODO(http://anglebug.com/5634): Fix calls to vkCmdCopyBufferToImage() with images smaller
+    // than the compressed format block size.
+    ANGLE_SKIP_TEST_IF(isAllocateNonZeroMemoryEnabled());
+
+    constexpr uint32_t kSize             = 4;
+    constexpr size_t kNumLevels          = 3;
+    const uint8_t CompressedImageETC1[8] = {0x0, 0x0, 0xf8, 0x2, 0xff, 0xff, 0x0, 0x0};
+
+    GLTexture srcTexture;
+    glBindTexture(GL_TEXTURE_2D, srcTexture);
+    for (size_t level = 0; level < kNumLevels; ++level)
+    {
+        glCompressedTexImage2D(GL_TEXTURE_2D, level, GL_ETC1_RGB8_OES, kSize >> level,
+                               kSize >> level, 0, 8, CompressedImageETC1);
+        EXPECT_GL_NO_ERROR();
+    }
+
+    GLTexture destTexture;
+    glBindTexture(GL_TEXTURE_2D, destTexture);
+    for (size_t level = 0; level < kNumLevels; ++level)
+    {
+        glCompressedTexImage2D(GL_TEXTURE_2D, level, GL_ETC1_RGB8_OES, kSize >> level,
+                               kSize >> level, 0, 8, nullptr);
+        EXPECT_GL_NO_ERROR();
+    }
+
+    glBindTexture(GL_TEXTURE_2D, 0);
+
+    // copy
+    for (size_t level = 0; level < kNumLevels; ++level)
+    {
+        glCopyImageSubDataEXT(srcTexture, GL_TEXTURE_2D, level, 0, 0, 0, destTexture, GL_TEXTURE_2D,
+                              level, 0, 0, 0, kSize >> level, kSize >> level, 1);
+        EXPECT_GL_NO_ERROR();
+    }
+}
+
 // Test GL_EXT_copy_image copy with a non-zero base level
 TEST_P(Texture2DTestES3, CopyImageBaseLevel1)
 {

src/tests/test_utils/ANGLETest.h

@@ -524,6 +524,11 @@ class ANGLETestBase
 
     bool platformSupportsMultithreading() const;
 
+    bool isAllocateNonZeroMemoryEnabled() const
+    {
+        return mCurrentParams->getAllocateNonZeroMemoryFeature() == EGL_TRUE;
+    }
+
   private:
     void checkD3D11SDKLayersMessages();
 

src/tests/test_utils/angle_test_configs.cpp

@@ -49,6 +49,11 @@ bool PlatformParameters::isSwiftshader() const
     return eglParameters.deviceType == EGL_PLATFORM_ANGLE_DEVICE_TYPE_SWIFTSHADER_ANGLE;
 }
 
+EGLint PlatformParameters::getAllocateNonZeroMemoryFeature() const
+{
+    return eglParameters.allocateNonZeroMemoryFeature;
+}
+
 void PlatformParameters::initDefaultParameters()
 {
     // Default debug layers to enabled in tests.

src/tests/test_utils/angle_test_configs.h

@@ -34,6 +34,7 @@ struct PlatformParameters
     EGLint getRenderer() const;
     EGLint getDeviceType() const;
     bool isSwiftshader() const;
+    EGLint getAllocateNonZeroMemoryFeature() const;
 
     void initDefaultParameters();