Convert SIMD wasm ops to runtime function calls

src/wasm/wasm-opcodes.cc

 // Copyright 2015 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.
 
 #include "src/wasm/wasm-opcodes.h"
 #include "src/messages.h"
 #include "src/signature.h"
 
 namespace v8 {
 namespace internal {
@@ skipping 50 matching lines @@
   static const FunctionSig kSig_##name(             \
       1, static_cast<int>(arraysize(kTypes_##name)) - 1, kTypes_##name);
 
 FOREACH_SIGNATURE(DECLARE_SIG)
 
 #define DECLARE_SIG_ENTRY(name, ...) &kSig_##name,
 
 static const FunctionSig* kSimpleExprSigs[] = {
     nullptr, FOREACH_SIGNATURE(DECLARE_SIG_ENTRY)};
 
+#define DECLARE_SIMD_SIG_ENTRY(name, ...) &kSig_##name,
+
+static const FunctionSig* kSimdExprSigs[] = {
+    nullptr, FOREACH_SIMD_SIGNATURE(DECLARE_SIMD_SIG_ENTRY)};
+
 static byte kSimpleExprSigTable[256];
+static byte kSimdExprSigTable[256];
 
 // Initialize the signature table.
 static void InitSigTable() {
 #define SET_SIG_TABLE(name, opcode, sig) \
   kSimpleExprSigTable[opcode] = static_cast<int>(kSigEnum_##sig) + 1;
   FOREACH_SIMPLE_OPCODE(SET_SIG_TABLE);
   FOREACH_SIMPLE_MEM_OPCODE(SET_SIG_TABLE);
   FOREACH_ASMJS_COMPAT_OPCODE(SET_SIG_TABLE);
 #undef SET_SIG_TABLE
 }
 
+// Initialize the signature table.

[titzer, 2016/07/08 14:16:03]

You can just merge this with the above function and rename it to
InitSigTables().

[gdeepti, 2016/07/11 09:50:34]

Done.

+static void InitSimdSigTable() {
+  byte simd_index;
+#define SET_SIG_TABLE(name, opcode, sig) \
+  simd_index = opcode & 0xff;            \
+  kSimdExprSigTable[simd_index] = static_cast<int>(kSigEnum_##sig) + 1;
+  FOREACH_SIMD_OPCODE(SET_SIG_TABLE)
+#undef SET_SIG_TABLE
+}
+
 class SigTable {
  public:
   SigTable() {
     // TODO(ahaas): Move {InitSigTable} into the class.
     InitSigTable();
+    InitSimdSigTable();
   }
   FunctionSig* Signature(WasmOpcode opcode) const {
     return const_cast<FunctionSig*>(
         kSimpleExprSigs[kSimpleExprSigTable[static_cast<byte>(opcode)]]);
   }
+  FunctionSig* SimdSignature(WasmOpcode opcode) const {
+    return const_cast<FunctionSig*>(
+        kSimdExprSigs[kSimdExprSigTable[static_cast<byte>(opcode & 0xff)]]);
+  }
 };
 
 static base::LazyInstance<SigTable>::type sig_table = LAZY_INSTANCE_INITIALIZER;
 
 FunctionSig* WasmOpcodes::Signature(WasmOpcode opcode) {
-  return sig_table.Get().Signature(opcode);
+  if (opcode >> 8 == kSimdPrefix) {
+    return sig_table.Get().SimdSignature(opcode);
+  } else {
+    return sig_table.Get().Signature(opcode);
+  }
 }
 
 // TODO(titzer): pull WASM_64 up to a common header.
 #if !V8_TARGET_ARCH_32_BIT || V8_TARGET_ARCH_X64
 #define WASM_64 1
 #else
 #define WASM_64 0
 #endif
 
 int WasmOpcodes::TrapReasonToMessageId(TrapReason reason) {
   switch (reason) {
 #define TRAPREASON_TO_MESSAGE(name) \
   case k##name:                     \
     return MessageTemplate::kWasm##name;
     FOREACH_WASM_TRAPREASON(TRAPREASON_TO_MESSAGE)
 #undef TRAPREASON_TO_MESSAGE
     default:
       return MessageTemplate::kNone;
   }
 }
 
 const char* WasmOpcodes::TrapReasonMessage(TrapReason reason) {
   return MessageTemplate::TemplateString(TrapReasonToMessageId(reason));
 }
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8