Convert SIMD wasm ops to runtime function calls

src/compiler/simd-lowering.h

Index: src/compiler/simd-lowering.h
diff --git a/src/compiler/simd-lowering.h b/src/compiler/simd-lowering.h
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index 0000000000000000000000000000000000000000..12a40251f7a83e894d9788471c60c9456dcb371d
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+++ b/src/compiler/simd-lowering.h
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+// Copyright 2016 the V8 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 V8_COMPILER_SIMD_LOWERING_H_
+#define V8_COMPILER_SIMD_LOWERING_H_
+
+#include "src/compiler/graph-reducer.h"
+#include "src/compiler/wasm-compiler.h"
+#include "src/runtime/runtime.h"
+
+namespace v8 {
+namespace internal {
+namespace compiler {
+
+typedef Signature<Conversion> ConversionSignature;
+
+class SimdLowering final : public Reducer {
+ public:
+  SimdLowering(Zone* zone, WasmGraphBuilder* builder)
+      : builder_(builder), zone_(zone) {
+    InitializeSignatures();
+  }
+  virtual ~SimdLowering();
+  Reduction Reduce(Node* node) override;
+
+ private:
+  void InitializeSignatures();
+
+  ConversionSignature* SigCreateInt32x4;
+  ConversionSignature* SigCreateFloat32x4;
+  ConversionSignature* SigCreateInt16x8;
+  ConversionSignature* SigCreateInt8x16;
+  ConversionSignature* SigExtractLaneInt;
+  ConversionSignature* SigExtractLaneFloat;
+  ConversionSignature* SigDefault;
+
+  WasmGraphBuilder* builder_;
+  Zone* zone_;
+};
+
+}  // namespace compiler
+}  // namespace internal
+}  // namespace v8
+
+#endif  // V8_COMPILER_SIMD_LOWERING_H_