WIP [esnext] implement async iteration proposal

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 258 matching lines @@
   /* Update the pending message */                                             \
   V(SetPendingMessage, AccumulatorUse::kReadWrite)                             \
                                                                                \
   /* Non-local flow control */                                                 \
   V(Throw, AccumulatorUse::kRead)                                              \
   V(ReThrow, AccumulatorUse::kRead)                                            \
   V(Return, AccumulatorUse::kRead)                                             \
                                                                                \
   /* Generators */                                                             \
   V(SuspendGenerator, AccumulatorUse::kRead, OperandType::kReg)                \
+  V(AwaitGenerator, AccumulatorUse::kRead, OperandType::kReg)                  \
   V(ResumeGenerator, AccumulatorUse::kWrite, OperandType::kReg)                \
                                                                                \
   /* Debugger */                                                               \
   V(Debugger, AccumulatorUse::kNone)                                           \
                                                                                \
   /* Debug Breakpoints - one for each possible size of unscaled bytecodes */   \
   /* and one for each operand widening prefix bytecode                    */   \
   V(DebugBreak0, AccumulatorUse::kRead)                                        \
   V(DebugBreak1, AccumulatorUse::kRead, OperandType::kReg)                     \
   V(DebugBreak2, AccumulatorUse::kRead, OperandType::kReg, OperandType::kReg)  \
@@ skipping 527 matching lines @@
 };
 
 V8_EXPORT_PRIVATE std::ostream& operator<<(std::ostream& os,
                                            const Bytecode& bytecode);
 
 }  // namespace interpreter
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_INTERPRETER_BYTECODES_H_