Fix checks to bit flags of PreParserExpression

src/preparser.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_PREPARSER_H
 #define V8_PREPARSER_H
 
 #include "src/v8.h"
 
 #include "src/func-name-inferrer.h"
@@ skipping 658 matching lines @@
   PreParserIdentifier AsIdentifier() const {
     ASSERT(IsIdentifier());
     return PreParserIdentifier(
         static_cast<PreParserIdentifier::Type>(code_ >> kIdentifierShift));
   }
 
   bool IsStringLiteral() const {
     return (code_ & kTypeMask) == kTypeStringLiteral;
   }
 
-  bool IsUseStrictLiteral() {
+  bool IsUseStrictLiteral() const {
     return (code_ & kUseStrictString) == kUseStrictString;
   }
 
-  bool IsThis() { return code_ == kThisExpression; }
+  bool IsThis() const { return (code_ & kThisExpression) == kThisExpression; }

[wingo, 2014/07/23 12:54:55]

Since the kThisExpression et al are just bitflags I would write "return code_ &
kThisExpression" instead, without the ==.  That's just me though.  Looks good to
this non-owner, please pass on to an owner.

[Sven Panne, 2014/07/23 13:26:05]

For consistency, I would leave it as it is. All this bit-fiddling has to be
abstracted, anyway. Using one enum for different purposes without any
abstraction is not nice...

 
-  bool IsThisProperty() { return code_ == kThisPropertyExpression; }
-
-  bool IsProperty() {
-    return code_ == kPropertyExpression || code_ == kThisPropertyExpression;
+  bool IsThisProperty() const {
+    return (code_ & kThisPropertyExpression) == kThisPropertyExpression;
   }
 
-  bool IsCall() { return code_ == kCallExpression; }
+  bool IsProperty() const {
+    return (code_ & kPropertyExpression) == kPropertyExpression ||
+           (code_ & kThisPropertyExpression) == kThisPropertyExpression;
+  }
 
-  bool IsValidReferenceExpression() {
+  bool IsCall() const { return (code_ & kCallExpression) == kCallExpression; }
+
+  bool IsValidReferenceExpression() const {
     return IsIdentifier() || IsProperty();
   }
 
   bool IsValidArrowParamList() const {
     return (ArrowParamListBit() & kBinaryOperationArrowParamList) != 0 &&
            (code_ & kMultiParenthesizedExpression) == 0;
   }
 
   // At the moment PreParser doesn't track these expression types.
   bool IsFunctionLiteral() const { return false; }
@@ skipping 1912 matching lines @@
       parser()->ReportMessage("accessor_get_set");
     }
     *ok = false;
   }
 }
 
 
 } }  // v8::internal
 
 #endif  // V8_PREPARSER_H