Remove debug info from SPIR-V

When dcheck_always_on=false, the SPIR-V transformer will strip all debug
information to reduce the SPIR-V binary size.

Running T-Rex shows about 27% reduction in the SPIR-V binary size.

Bug: angleproject:4680
Test: CQ
Change-Id: Id9d0189cdc9c12fa5a1741cf62ef549a533cdf93
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2267358
Commit-Queue: Tim Van Patten <timvp@google.com>
Reviewed-by: Jamie Madill <jmadill@chromium.org>
Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>

src/libANGLE/renderer/glslang_wrapper_utils.cpp

@@ -907,6 +907,7 @@ class SpirvTransformer final : angle::NonCopyable
   public:
     SpirvTransformer(const std::vector<uint32_t> &spirvBlobIn,
                      bool removeEarlyFragmentTestsOptimization,
+                     bool removeDebugInfo,
                      const ShaderInterfaceVariableInfoMap &variableInfoMap,
                      gl::ShaderType shaderType,
                      SpirvBlob *spirvBlobOut)
@@ -919,6 +920,7 @@ class SpirvTransformer final : angle::NonCopyable
         gl::ShaderBitSet allStages;
         allStages.set();
         mRemoveEarlyFragmentTestsOptimization = removeEarlyFragmentTestsOptimization;
+        mRemoveDebugInfo                      = removeDebugInfo;
         mBuiltinVariableInfo.activeStages     = allStages;
     }
 
@@ -969,6 +971,7 @@ class SpirvTransformer final : angle::NonCopyable
     bool mHasTransformFeedbackOutput;
 
     bool mRemoveEarlyFragmentTestsOptimization;
+    bool mRemoveDebugInfo;
 
     // Input shader variable info map:
     const ShaderInterfaceVariableInfoMap &mVariableInfoMap;
@@ -1154,6 +1157,21 @@ void SpirvTransformer::transformInstruction()
         // Look at global declaration opcodes.
         switch (opCode)
         {
+            case spv::OpSourceContinued:
+            case spv::OpSource:
+            case spv::OpSourceExtension:
+            case spv::OpName:
+            case spv::OpMemberName:
+            case spv::OpString:
+            case spv::OpLine:
+            case spv::OpNoLine:
+            case spv::OpModuleProcessed:
+                if (mRemoveDebugInfo)
+                {
+                    // Strip debug info to reduce binary size.
+                    transformed = true;
+                }
+                break;
             case spv::OpCapability:
                 transformed = transformCapability(instruction, wordCount);
                 break;
@@ -1866,6 +1884,7 @@ void GlslangGetShaderSource(GlslangSourceOptions &options,
 angle::Result GlslangTransformSpirvCode(const GlslangErrorCallback &callback,
                                         const gl::ShaderType shaderType,
                                         bool removeEarlyFragmentTestsOptimization,
+                                        bool removeDebugInfo,
                                         const ShaderInterfaceVariableInfoMap &variableInfoMap,
                                         const SpirvBlob &initialSpirvBlob,
                                         SpirvBlob *spirvBlobOut)
@@ -1877,7 +1896,7 @@ angle::Result GlslangTransformSpirvCode(const GlslangErrorCallback &callback,
 
     // Transform the SPIR-V code by assigning location/set/binding values.
     SpirvTransformer transformer(initialSpirvBlob, removeEarlyFragmentTestsOptimization,
-                                 variableInfoMap, shaderType, spirvBlobOut);
+                                 removeDebugInfo, variableInfoMap, shaderType, spirvBlobOut);
     ANGLE_GLSLANG_CHECK(callback, transformer.transform(), GlslangError::InvalidSpirv);
 
     ASSERT(ValidateSpirv(*spirvBlobOut));

src/libANGLE/renderer/glslang_wrapper_utils.h

@@ -118,6 +118,7 @@ void GlslangGetShaderSource(GlslangSourceOptions &options,
 angle::Result GlslangTransformSpirvCode(const GlslangErrorCallback &callback,
                                         const gl::ShaderType shaderType,
                                         bool removeEarlyFragmentTestsOptimization,
+                                        bool removeDebugInfo,
                                         const ShaderInterfaceVariableInfoMap &variableInfoMap,
                                         const SpirvBlob &initialSpirvBlob,
                                         SpirvBlob *spirvBlobOut);

src/libANGLE/renderer/metal/mtl_glslang_utils.mm

@@ -256,7 +256,7 @@ void GlslangGetShaderSource(const gl::ProgramState &programState,
         // do not have ability to add back in at initProgram time.
         angle::Result status = GlslangTransformSpirvCode(
             [context](GlslangError error) { return HandleError(context, error); }, shaderType,
-            false, variableInfoMap[shaderType], initialSpirvBlobs[shaderType],
+            false, false, variableInfoMap[shaderType], initialSpirvBlobs[shaderType],
             &(*shaderCodeOut)[shaderType]);
         if (status != angle::Result::Continue)
         {

src/libANGLE/renderer/vulkan/GlslangWrapperVk.cpp

@@ -91,8 +91,11 @@ angle::Result GlslangWrapperVk::TransformSpirV(
     const SpirvBlob &initialSpirvBlob,
     SpirvBlob *shaderCodeOut)
 {
+    const bool removeDebugInfo = !context->getRenderer()->getEnableValidationLayers();
+
     return GlslangTransformSpirvCode(
         [context](GlslangError error) { return ErrorHandler(context, error); }, shaderType,
-        removeEarlyFragmentTestsOptimization, variableInfoMap, initialSpirvBlob, shaderCodeOut);
+        removeEarlyFragmentTestsOptimization, removeDebugInfo, variableInfoMap, initialSpirvBlob,
+        shaderCodeOut);
 }
 }  // namespace rx

src/libANGLE/renderer/vulkan/RendererVk.h

@@ -258,6 +258,8 @@ class RendererVk : angle::NonCopyable
 
     vk::BufferHelper &getNullBuffer() { return mTheNullBuffer; }
 
+    bool getEnableValidationLayers() const { return mEnableValidationLayers; }
+
   private:
     angle::Result initializeDevice(DisplayVk *displayVk, uint32_t queueFamilyIndex);
     void ensureCapsInitialized() const;