[parser] PreParserExpression cleanup

src/preparser.h

Index: src/preparser.h
diff --git a/src/preparser.h b/src/preparser.h
index 18fc2330eedd7f646683035bba73e311d6f8d12a..15bef7c23529775f529ee789d09c3be1a984e027 100644
--- a/src/preparser.h
+++ b/src/preparser.h
@@ -921,19 +921,31 @@ class PreParserExpression {
   }
 
   static PreParserExpression StringLiteral() {
-    return PreParserExpression(TypeField::encode(kStringLiteralExpression));
+    return PreParserExpression(TypeField::encode(kStringLiteral));

[caitp (gmail), 2015/08/17 18:26:12]

the `Expression` suffix wasn't really adding anything

   }
 
   static PreParserExpression UseStrictStringLiteral() {
-    return PreParserExpression(TypeField::encode(kStringLiteralExpression) |
+    return PreParserExpression(TypeField::encode(kStringLiteral) |
                                IsUseStrictField::encode(true));
   }
 
   static PreParserExpression UseStrongStringLiteral() {
-    return PreParserExpression(TypeField::encode(kStringLiteralExpression) |
+    return PreParserExpression(TypeField::encode(kStringLiteral) |
                                IsUseStrongField::encode(true));
   }
 
+  static PreParserExpression NumberLiteral() {
+    return PreParserExpression(TypeField::encode(kNumberLiteral));

[caitp (gmail), 2015/08/17 18:26:12]

Just here for consistency --- might be useful for enabling the preparser to
discern between smi-able numbers and float-only numbers, but that's speculating.

+  }
+
+  static PreParserExpression ArrayLiteral() {
+    return PreParserExpression(TypeField::encode(kArrayLiteral));

[caitp (gmail), 2015/08/17 18:26:12]

I have uses for this in destructuring assignment, so that I can centralize a lot
of logic that was very distributed and convoluted in the old CL. Not positive if
it will work, but I'm going to try it on top of this CL first anyhow.

+  }
+
+  static PreParserExpression ObjectLiteral() {
+    return PreParserExpression(TypeField::encode(kObjectLiteral));
+  }
+
   static PreParserExpression This() {
     return PreParserExpression(TypeField::encode(kExpression) |
                                ExpressionTypeField::encode(kThisExpression));
@@ -978,19 +990,31 @@ class PreParserExpression {
   }
 
   bool IsStringLiteral() const {
-    return TypeField::decode(code_) == kStringLiteralExpression;
+    return TypeField::decode(code_) == kStringLiteral;
   }
 
   bool IsUseStrictLiteral() const {
-    return TypeField::decode(code_) == kStringLiteralExpression &&
+    return TypeField::decode(code_) == kStringLiteral &&
            IsUseStrictField::decode(code_);
   }
 
   bool IsUseStrongLiteral() const {
-    return TypeField::decode(code_) == kStringLiteralExpression &&
+    return TypeField::decode(code_) == kStringLiteral &&
            IsUseStrongField::decode(code_);
   }
 
+  bool IsNumberLiteral() const {
+    return TypeField::decode(code_) == kNumberLiteral;
+  }
+
+  bool IsArrayLiteral() const {
+    return TypeField::decode(code_) == kArrayLiteral;
+  }
+
+  bool IsObjectLiteral() const {
+    return TypeField::decode(code_) == kObjectLiteral;
+  }
+
   bool IsThis() const {
     return TypeField::decode(code_) == kExpression &&
            ExpressionTypeField::decode(code_) == kThisExpression;
@@ -1055,7 +1079,10 @@ class PreParserExpression {
   enum Type {
     kExpression,
     kIdentifierExpression,
-    kStringLiteralExpression,
+    kStringLiteral,
+    kNumberLiteral,
+    kArrayLiteral,
+    kObjectLiteral,
     kBinaryOperationExpression,
     kSpreadExpression
   };
@@ -1073,7 +1100,7 @@ class PreParserExpression {
       : code_(expression_code) {}
 
   // The first three bits are for the Type.
-  typedef BitField<Type, 0, 3> TypeField;
+  typedef BitField<Type, 0, 4> TypeField;

[caitp (gmail), 2015/08/17 18:26:11]

I guess this doesn't really need the extra bit --- revert this line?

 
   // The rest of the bits are interpreted depending on the value
   // of the Type field, so they can share the storage.
@@ -1177,11 +1204,11 @@ class PreParserFactory {
   explicit PreParserFactory(void* unused_value_factory) {}
   PreParserExpression NewStringLiteral(PreParserIdentifier identifier,
                                        int pos) {
-    return PreParserExpression::Default();
+    return PreParserExpression::StringLiteral();
   }
   PreParserExpression NewNumberLiteral(double number,
                                        int pos) {
-    return PreParserExpression::Default();
+    return PreParserExpression::NumberLiteral();
   }
   PreParserExpression NewRegExpLiteral(PreParserIdentifier js_pattern,
                                        PreParserIdentifier js_flags,
@@ -1194,12 +1221,12 @@ class PreParserFactory {
                                       int literal_index,
                                       bool is_strong,
                                       int pos) {
-    return PreParserExpression::Default();
+    return PreParserExpression::ArrayLiteral();
   }
   PreParserExpression NewArrayLiteral(PreParserExpressionList values,
                                       int first_spread_index, int literal_index,
                                       bool is_strong, int pos) {
-    return PreParserExpression::Default();
+    return PreParserExpression::ArrayLiteral();
   }
   PreParserExpression NewObjectLiteralProperty(PreParserExpression key,
                                                PreParserExpression value,
@@ -1220,7 +1247,7 @@ class PreParserFactory {
                                        bool has_function,
                                        bool is_strong,
                                        int pos) {
-    return PreParserExpression::Default();
+    return PreParserExpression::ObjectLiteral();
   }
   PreParserExpression NewVariableProxy(void* variable) {
     return PreParserExpression::Default();