Revert runtime lowering of wasm SIMD ops

test/mjsunit/wasm/wasm-constants.js

 // 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.
 
 // Flags: --expose-wasm
 
 function bytes() {
   var buffer = new ArrayBuffer(arguments.length);
   var view = new Uint8Array(buffer);
   for (var i = 0; i < arguments.length; i++) {
@@ skipping 289 matching lines @@
 var kExprF64SConvertI64 = 0xb0;
 var kExprF64UConvertI64 = 0xb1;
 var kExprF64ConvertF32 = 0xb2;
 var kExprF64ReinterpretI64 = 0xb3;
 var kExprI32ReinterpretF32 = 0xb4;
 var kExprI64ReinterpretF64 = 0xb5;
 var kExprI32Ror = 0xb6;
 var kExprI32Rol = 0xb7;
 var kExprI64Ror = 0xb8;
 var kExprI64Rol = 0xb9;
-var kExprSimdPrefix = 0xe5;
-var kExprI32x4Splat = 0x1b;
-var kExprI32x4ExtractLane = 0x1c;
 
 var kTrapUnreachable          = 0;
 var kTrapMemOutOfBounds       = 1;
 var kTrapDivByZero            = 2;
 var kTrapDivUnrepresentable   = 3;
 var kTrapRemByZero            = 4;
 var kTrapFloatUnrepresentable = 5;
 var kTrapFuncInvalid          = 6;
 var kTrapFuncSigMismatch      = 7;
 var kTrapInvalidIndex         = 8;
@@ skipping 20 matching lines @@
       }
       threwException = false;
     } catch (e) {
       assertEquals("object", typeof e);
       assertEquals(kTrapMsgs[trap], e.message);
       // Success.
       return;
     }
     throw new MjsUnitAssertionError("Did not trap, expected: " + kTrapMsgs[trap]);
 }