1 files changed, 85 insertions, 0 deletions
diff --git a/Source/ThirdParty/ANGLE/src/compiler/translator/BuiltInFunctionEmulator.h b/Source/ThirdParty/ANGLE/src/compiler/translator/BuiltInFunctionEmulator.h
new file mode 100644
index 000000000..6976edfd5
--- /dev/null
+++ b/Source/ThirdParty/ANGLE/src/compiler/translator/BuiltInFunctionEmulator.h
@@ -0,0 +1,85 @@
+//
+// Copyright (c) 2011 The ANGLE Project Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+//
+
+#ifndef COMPILER_TRANSLATOR_BUILTINFUNCTIONEMULATOR_H_
+#define COMPILER_TRANSLATOR_BUILTINFUNCTIONEMULATOR_H_
+
+#include "compiler/translator/InfoSink.h"
+#include "compiler/translator/IntermNode.h"
+
+//
+// This class decides which built-in functions need to be replaced with the
+// emulated ones.
+// It can be used to work around driver bugs or implement functions that are
+// not natively implemented on a specific platform.
+//
+class BuiltInFunctionEmulator
+{
+  public:
+    BuiltInFunctionEmulator();
+
+    void MarkBuiltInFunctionsForEmulation(TIntermNode *root);
+
+    void Cleanup();
+
+    // "name(" becomes "webgl_name_emu(".
+    static TString GetEmulatedFunctionName(const TString &name);
+
+    bool IsOutputEmpty() const;
+
+    // Output function emulation definition. This should be before any other
+    // shader source.
+    void OutputEmulatedFunctions(TInfoSinkBase &out) const;
+
+    // Add functions that need to be emulated.
+    void addEmulatedFunction(TOperator op, const TType *param, const char *emulatedFunctionDefinition);
+    void addEmulatedFunction(TOperator op, const TType *param1, const TType *param2,
+                             const char *emulatedFunctionDefinition);
+    void addEmulatedFunction(TOperator op, const TType *param1, const TType *param2, const TType *param3,
+                             const char *emulatedFunctionDefinition);
+
+  private:
+    class BuiltInFunctionEmulationMarker;
+
+    // Records that a function is called by the shader and might need to be
+    // emulated. If the function is not in mEmulatedFunctions, this becomes a
+    // no-op. Returns true if the function call needs to be replaced with an
+    // emulated one.
+    bool SetFunctionCalled(TOperator op, const TType &param);
+    bool SetFunctionCalled(TOperator op, const TType &param1, const TType &param2);
+    bool SetFunctionCalled(TOperator op, const TType &param1, const TType &param2, const TType &param3);
+
+    class FunctionId {
+      public:
+        FunctionId(TOperator op, const TType *param);
+        FunctionId(TOperator op, const TType *param1, const TType *param2);
+        FunctionId(TOperator op, const TType *param1, const TType *param2, const TType *param3);
+
+        bool operator==(const FunctionId &other) const;
+        bool operator<(const FunctionId &other) const;
+
+        FunctionId getCopy() const;
+      private:
+        TOperator mOp;
+
+        // The memory that these TType objects use is freed by PoolAllocator. The BuiltInFunctionEmulator's lifetime
+        // can extend until after the memory pool is freed, but that's not an issue since this class never destructs
+        // these objects.
+        const TType *mParam1;
+        const TType *mParam2;
+        const TType *mParam3;
+    };
+
+    bool SetFunctionCalled(const FunctionId &functionId);
+
+    // Map from function id to emulated function definition
+    std::map<FunctionId, std::string> mEmulatedFunctions;
+
+    // Called function ids
+    std::vector<FunctionId> mFunctions;
+};
+
+#endif  // COMPILER_TRANSLATOR_BUILTINFUNCTIONEMULATOR_H_