Vulkan: Fix draw with emulated xfb without xfb active
When transform feedback is not active, make sure the code that captures
xfb is not generated, even though it's guarded against with an if. This
is because no buffer is bound to the capture buffer, and by avoiding
generation of code that references that buffer, SwiftShader will not
attempt to access the missing descriptor set.
Currently, the actual declaration of the buffer is left in the SPIR-V,
which seems to be benign. If that causes issues in the future, the
SPIR-V transformer can be modified to remove that variable as well.
Bug: chromium:1209285
Change-Id: I83da8d1dea5390ecacc681f8ada9f586932deaa4
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3294661
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Tim Van Patten <timvp@google.com>
Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>
diff --git a/src/libANGLE/renderer/vulkan/ContextVk.cpp b/src/libANGLE/renderer/vulkan/ContextVk.cpp
index 884cef9..6b64dc2 100644
--- a/src/libANGLE/renderer/vulkan/ContextVk.cpp
+++ b/src/libANGLE/renderer/vulkan/ContextVk.cpp
@@ -4465,6 +4465,12 @@
{
invalidateGraphicsDriverUniforms();
invalidateCurrentTransformFeedbackBuffers();
+
+ // Invalidate the graphics pipeline too. On transform feedback state change, the current
+ // program may be used again, and it should switch between outputting transform feedback and
+ // not.
+ invalidateCurrentGraphicsPipeline();
+ resetCurrentGraphicsPipeline();
}
}
diff --git a/src/libANGLE/renderer/vulkan/ProgramExecutableVk.cpp b/src/libANGLE/renderer/vulkan/ProgramExecutableVk.cpp
index 35b3842..983f286 100644
--- a/src/libANGLE/renderer/vulkan/ProgramExecutableVk.cpp
+++ b/src/libANGLE/renderer/vulkan/ProgramExecutableVk.cpp
@@ -208,8 +208,9 @@
options.shaderType = shaderType;
options.removeEarlyFragmentTestsOptimization =
shaderType == gl::ShaderType::Fragment && optionBits.removeEarlyFragmentTestsOptimization;
- options.removeDebugInfo = !contextVk->getRenderer()->getEnableValidationLayers();
- options.isTransformFeedbackStage = isLastPreFragmentStage && isTransformFeedbackProgram;
+ options.removeDebugInfo = !contextVk->getRenderer()->getEnableValidationLayers();
+ options.isTransformFeedbackStage = isLastPreFragmentStage && isTransformFeedbackProgram &&
+ !optionBits.removeTransformFeedbackEmulation;
options.isTransformFeedbackEmulated = contextVk->getFeatures().emulateTransformFeedback.enabled;
options.negativeViewportSupported = contextVk->getFeatures().supportsNegativeViewport.enabled;
@@ -850,6 +851,9 @@
mTransformOptions.enableLineRasterEmulation = contextVk->isBresenhamEmulationEnabled(mode);
mTransformOptions.surfaceRotation = ToUnderlying(desc.getSurfaceRotation());
mTransformOptions.enableDepthCorrection = !glState.isClipControlDepthZeroToOne();
+ mTransformOptions.removeTransformFeedbackEmulation =
+ contextVk->getFeatures().emulateTransformFeedback.enabled &&
+ !glState.isTransformFeedbackActiveUnpaused();
// This must be called after mTransformOptions have been set.
ProgramInfo &programInfo = getGraphicsProgramInfo(mTransformOptions);
diff --git a/src/libANGLE/renderer/vulkan/ProgramExecutableVk.h b/src/libANGLE/renderer/vulkan/ProgramExecutableVk.h
index 262bd85..16a6040 100644
--- a/src/libANGLE/renderer/vulkan/ProgramExecutableVk.h
+++ b/src/libANGLE/renderer/vulkan/ProgramExecutableVk.h
@@ -53,8 +53,9 @@
uint8_t removeEarlyFragmentTestsOptimization : 1;
uint8_t surfaceRotation : 3;
uint8_t enableDepthCorrection : 1;
- uint8_t reserved : 2; // must initialize to zero
- static constexpr uint32_t kPermutationCount = 0x1 << 6;
+ uint8_t removeTransformFeedbackEmulation : 1;
+ uint8_t reserved : 1; // must initialize to zero
+ static constexpr uint32_t kPermutationCount = 0x1 << 7;
};
static_assert(sizeof(ProgramTransformOptions) == 1, "Size check failed");
static_assert(static_cast<int>(SurfaceRotation::EnumCount) <= 8, "Size check failed");
diff --git a/src/tests/gl_tests/TransformFeedbackTest.cpp b/src/tests/gl_tests/TransformFeedbackTest.cpp
index a12b52d..b03d860 100644
--- a/src/tests/gl_tests/TransformFeedbackTest.cpp
+++ b/src/tests/gl_tests/TransformFeedbackTest.cpp
@@ -86,6 +86,87 @@
void midRecordOpDoesNotContributeTest(std::function<void()> op);
};
+// Test that using a transform feedback program without transform feedback active works, and that
+// using it with transform feedback afterwards also works.
+TEST_P(TransformFeedbackTest, NoCaptureThenCapture)
+{
+ constexpr char kFS[] = R"(#version 300 es
+out mediump vec4 color;
+void main()
+{
+ color = vec4(0.6, 0.0, 0.0, 1.0);
+})";
+
+ // Set the program's transform feedback varyings (just gl_Position)
+ std::vector<std::string> tfVaryings;
+ tfVaryings.push_back("gl_Position");
+ ANGLE_GL_PROGRAM_TRANSFORM_FEEDBACK(drawColor, essl3_shaders::vs::Simple(), kFS, tfVaryings,
+ GL_INTERLEAVED_ATTRIBS);
+
+ glUseProgram(drawColor);
+ GLint positionLocation = glGetAttribLocation(drawColor, essl3_shaders::PositionAttrib());
+ ASSERT_NE(positionLocation, -1);
+
+ const GLfloat vertices[] = {
+ -1.0f, 1.0f, 0.5f, -1.0f, -1.0f, 0.5f, 1.0f, -1.0f, 0.5f,
+ -1.0f, 1.0f, 0.5f, 1.0f, -1.0f, 0.5f, 1.0f, 1.0f, 0.5f,
+ };
+
+ glVertexAttribPointer(positionLocation, 3, GL_FLOAT, GL_FALSE, 0, vertices);
+ glEnableVertexAttribArray(positionLocation);
+
+ glClearColor(0, 0, 0, 0);
+ glClear(GL_COLOR_BUFFER_BIT);
+
+ glEnable(GL_BLEND);
+ glBlendFunc(GL_ONE, GL_ONE);
+
+ GLQuery primitivesWrittenQuery;
+ glBeginQuery(GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN, primitivesWrittenQuery);
+ ASSERT_GL_NO_ERROR();
+
+ // Don't bind a buffer for transform feedback output and don't active transform feedback.
+ glDrawArrays(GL_TRIANGLES, 0, 6);
+
+ // Draw again, with xfb capture enabled.
+ glBindBufferBase(GL_TRANSFORM_FEEDBACK_BUFFER, 0, mTransformFeedbackBuffer);
+ glBeginTransformFeedback(GL_TRIANGLES);
+ glDrawArrays(GL_TRIANGLES, 0, 6);
+ glEndTransformFeedback();
+
+ glEndQuery(GL_TRANSFORM_FEEDBACK_PRIMITIVES_WRITTEN);
+
+ // Ensure that both draw calls succeed.
+ EXPECT_PIXEL_COLOR_EQ(0, 0, GLColor::red);
+ EXPECT_GL_NO_ERROR();
+
+ GLuint primitivesWritten = 0;
+ glGetQueryObjectuiv(primitivesWrittenQuery, GL_QUERY_RESULT_EXT, &primitivesWritten);
+
+ // Ensure that only one draw call produced transform feedback data.
+ EXPECT_EQ(2u, primitivesWritten);
+ EXPECT_GL_NO_ERROR();
+
+ // Ensure that triangles were actually captured.
+ void *mappedBuffer =
+ glMapBufferRange(GL_TRANSFORM_FEEDBACK_BUFFER, 0, sizeof(float) * 24, GL_MAP_READ_BIT);
+ ASSERT_NE(nullptr, mappedBuffer);
+
+ const GLfloat expect[] = {
+ -1.0f, 1.0f, 0.5f, 1.0f, -1.0f, -1.0f, 0.5f, 1.0f, 1.0f, -1.0f, 0.5f, 1.0f,
+ -1.0f, 1.0f, 0.5f, 1.0f, 1.0f, -1.0f, 0.5f, 1.0f, 1.0f, 1.0f, 0.5f, 1.0f,
+ };
+
+ float *mappedFloats = static_cast<float *>(mappedBuffer);
+ for (uint32_t i = 0; i < 24; ++i)
+ {
+ EXPECT_EQ(mappedFloats[i], expect[i]);
+ }
+ glUnmapBuffer(GL_TRANSFORM_FEEDBACK_BUFFER);
+
+ EXPECT_GL_NO_ERROR();
+}
+
TEST_P(TransformFeedbackTest, ZeroSizedViewport)
{
// http://anglebug.com/5154
