[esnext] implement frontend changes for async/await proposal

src/globals.h

 // Copyright 2012 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_GLOBALS_H_
 #define V8_GLOBALS_H_
 
 #include <stddef.h>
 #include <stdint.h>
 
@@ skipping 945 matching lines @@
   kNormalFunction = 0,
   kArrowFunction = 1 << 0,
   kGeneratorFunction = 1 << 1,
   kConciseMethod = 1 << 2,
   kConciseGeneratorMethod = kGeneratorFunction | kConciseMethod,
   kDefaultConstructor = 1 << 3,
   kSubclassConstructor = 1 << 4,
   kBaseConstructor = 1 << 5,
   kGetterFunction = 1 << 6,
   kSetterFunction = 1 << 7,
+  kAsyncFunction = 1 << 8,
   kAccessorFunction = kGetterFunction | kSetterFunction,
   kDefaultBaseConstructor = kDefaultConstructor | kBaseConstructor,
   kDefaultSubclassConstructor = kDefaultConstructor | kSubclassConstructor,
   kClassConstructor =
       kBaseConstructor | kSubclassConstructor | kDefaultConstructor,
+  kAsyncArrowFunction = kArrowFunction | kAsyncFunction,
+  kAsyncConciseMethod = kAsyncFunction | kConciseMethod
 };
 
 inline bool IsValidFunctionKind(FunctionKind kind) {
   return kind == FunctionKind::kNormalFunction ||
          kind == FunctionKind::kArrowFunction ||
          kind == FunctionKind::kGeneratorFunction ||
          kind == FunctionKind::kConciseMethod ||
          kind == FunctionKind::kConciseGeneratorMethod ||
          kind == FunctionKind::kGetterFunction ||
          kind == FunctionKind::kSetterFunction ||
          kind == FunctionKind::kAccessorFunction ||
          kind == FunctionKind::kDefaultBaseConstructor ||
          kind == FunctionKind::kDefaultSubclassConstructor ||
          kind == FunctionKind::kBaseConstructor ||
-         kind == FunctionKind::kSubclassConstructor;
+         kind == FunctionKind::kSubclassConstructor ||
+         kind == FunctionKind::kAsyncFunction ||
+         kind == FunctionKind::kAsyncArrowFunction ||
+         kind == FunctionKind::kAsyncConciseMethod;
 }
 
 
 inline bool IsArrowFunction(FunctionKind kind) {
   DCHECK(IsValidFunctionKind(kind));
   return kind & FunctionKind::kArrowFunction;
 }
 
 
 inline bool IsGeneratorFunction(FunctionKind kind) {
   DCHECK(IsValidFunctionKind(kind));
   return kind & FunctionKind::kGeneratorFunction;
 }
 
+inline bool IsAsyncFunction(FunctionKind kind) {
+  DCHECK(IsValidFunctionKind(kind));
+  return kind & FunctionKind::kAsyncFunction;
+}
 
 inline bool IsConciseMethod(FunctionKind kind) {
   DCHECK(IsValidFunctionKind(kind));
   return kind & FunctionKind::kConciseMethod;
 }
 
 inline bool IsGetterFunction(FunctionKind kind) {
   DCHECK(IsValidFunctionKind(kind));
   return kind & FunctionKind::kGetterFunction;
 }
@@ skipping 42 matching lines @@
 }
 
 
 inline uint32_t ObjectHash(Address address) {
   // All objects are at least pointer aligned, so we can remove the trailing
   // zeros.
   return static_cast<uint32_t>(bit_cast<uintptr_t>(address) >>
                                kPointerSizeLog2);
 }
 
+enum class MethodKind {
+  None = 0,
+  Static = 1 << 0,
+  Generator = 1 << 1,
+  StaticGenerator = Static | Generator,
+  Async = 1 << 2,
+  StaticAsync = Static | Async,
+};

[Dan Ehrenberg, 2016/05/11 21:04:17]

This seems to overlap a lot with ObjectLiteralProperty::Kind and FunctionKind,
and the information doesn't seem to be used all that much. Can we make do with
fewer concepts, maybe merge some of these together?

[caitp (gmail), 2016/05/11 21:14:07]

goal was to get rid of a boolean trap in CheckProperty, rather than adding a new
one. its really parser-specific and can be moved out of globals.h, but having it
here simplifies creating the ast node a bit. I am a bit iffy about merging it
into PropertyKind, as backends may rely on it, but if you have ideas to do it in
an uninvasive way, i can try it

+
+inline bool IsValidMethodKind(MethodKind kind) {
+  return kind == MethodKind::None || kind == MethodKind::Static ||
+         kind == MethodKind::Generator || kind == MethodKind::StaticGenerator ||
+         kind == MethodKind::Async || kind == MethodKind::StaticAsync;
+}
+
+static inline MethodKind operator|(MethodKind lhs, MethodKind rhs) {
+  typedef unsigned char T;
+  return static_cast<MethodKind>(static_cast<T>(lhs) | static_cast<T>(rhs));
+}
+
+static inline MethodKind& operator|=(MethodKind& lhs, const MethodKind& rhs) {
+  lhs = lhs | rhs;
+  DCHECK(IsValidMethodKind(lhs));
+  return lhs;
+}
+
+static inline bool operator&(MethodKind bitfield, MethodKind mask) {
+  typedef unsigned char T;
+  return static_cast<T>(bitfield) & static_cast<T>(mask);
+}
+
+inline bool IsMethod(MethodKind kind) { return kind != MethodKind::None; }

[Dan Ehrenberg, 2016/05/11 21:04:17]

Huh? What about an ordinary non-static non-generator non-async concise method?

[caitp (gmail), 2016/05/11 21:14:07]

good point, although it doesnt seem to actually matter in this CL

+
+inline bool IsStaticMethod(MethodKind kind) {
+  return kind & MethodKind::Static;
+}
+
+inline bool IsGeneratorMethod(MethodKind kind) {
+  return kind & MethodKind::Generator;
+}
+
+inline bool IsAsyncMethod(MethodKind kind) { return kind & MethodKind::Async; }
+
 }  // namespace internal
 }  // namespace v8
 
 namespace i = v8::internal;
 
 #endif  // V8_GLOBALS_H_