[Interpreter] Optimize equality check with null/undefined with a check on the map.

src/interpreter/bytecodes.h

 // 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.
 
 #ifndef V8_INTERPRETER_BYTECODES_H_
 #define V8_INTERPRETER_BYTECODES_H_
 
 #include <cstdint>
 #include <iosfwd>
 #include <string>
@@ skipping 165 matching lines @@
     OperandType::kIdx)                                                         \
   V(TestGreaterThan, AccumulatorUse::kReadWrite, OperandType::kReg,            \
     OperandType::kIdx)                                                         \
   V(TestLessThanOrEqual, AccumulatorUse::kReadWrite, OperandType::kReg,        \
     OperandType::kIdx)                                                         \
   V(TestGreaterThanOrEqual, AccumulatorUse::kReadWrite, OperandType::kReg,     \
     OperandType::kIdx)                                                         \
   V(TestInstanceOf, AccumulatorUse::kReadWrite, OperandType::kReg)             \
   V(TestIn, AccumulatorUse::kReadWrite, OperandType::kReg)                     \
                                                                                \
+  /* TestEqual with Null or Undefined */                                       \
+  V(TestUndetectable, AccumulatorUse::kWrite, OperandType::kReg)               \
+                                                                               \
   /* Cast operators */                                                         \
   V(ToName, AccumulatorUse::kRead, OperandType::kRegOut)                       \
   V(ToNumber, AccumulatorUse::kRead, OperandType::kRegOut)                     \
   V(ToObject, AccumulatorUse::kRead, OperandType::kRegOut)                     \
                                                                                \
   /* Literals */                                                               \
   V(CreateRegExpLiteral, AccumulatorUse::kWrite, OperandType::kIdx,            \
     OperandType::kIdx, OperandType::kFlag8)                                    \
   V(CreateArrayLiteral, AccumulatorUse::kWrite, OperandType::kIdx,             \
     OperandType::kIdx, OperandType::kFlag8)                                    \
@@ skipping 210 matching lines @@
       case Bytecode::kLogicalNot:
       case Bytecode::kTestEqual:
       case Bytecode::kTestNotEqual:
       case Bytecode::kTestEqualStrict:
       case Bytecode::kTestLessThan:
       case Bytecode::kTestLessThanOrEqual:
       case Bytecode::kTestGreaterThan:
       case Bytecode::kTestGreaterThanOrEqual:
       case Bytecode::kTestInstanceOf:
       case Bytecode::kTestIn:
+      case Bytecode::kTestUndetectable:
       case Bytecode::kForInContinue:
         return true;
       default:
         return false;
     }
   }
 
   // Return true if |bytecode| is an accumulator load without effects,
   // e.g. LdaConstant, LdaTrue, Ldar.
   static CONSTEXPR bool IsAccumulatorLoadWithoutEffects(Bytecode bytecode) {
@@ skipping 327 matching lines @@
 #undef CONSTEXPR
 
 V8_EXPORT_PRIVATE std::ostream& operator<<(std::ostream& os,
                                            const Bytecode& bytecode);
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_INTERPRETER_BYTECODES_H_