Changeset 63055 in webkit for trunk/JavaScriptCore/parser/JSParser.cpp

Timestamp:

Jul 10, 2010, 5:11:08 PM (15 years ago)

Author:

[email protected]

Message:

2010-07-10 Oliver Hunt <​[email protected]>

Reviewed by Gavin Barraclough.

Remove switches from inner expression loops in the parser
​https://bugs.webkit.org/show_bug.cgi?id=42035

Use bitmasks and flags on the token types to identify unary and
binary operators, rather than switching on the token type to
identify them.

• parser/JSParser.cpp: (JSC::isUnaryOp): (JSC::JSParser::isBinaryOperator):
• parser/JSParser.h: (JSC::):

File:

• trunk/JavaScriptCore/parser/JSParser.cpp (modified) (3 diffs)

trunk/JavaScriptCore/parser/JSParser.cpp

@@ -59 +59 @@
 #define TreeProperty typename TreeBuilder::Property
 #define TreePropertyList typename TreeBuilder::PropertyList
+
+COMPILE_ASSERT(LastUntaggedToken < 64, LessThan64UntaggedTokens);
 
 // This matches v8
@@ -161 +163 @@
     enum FunctionRequirements { FunctionNoRequirements, FunctionNeedsName };
     template <FunctionRequirements, class TreeBuilder> bool parseFunctionInfo(TreeBuilder&, const Identifier*&, TreeFormalParameterList&, TreeFunctionBody&, int& openBrace, int& closeBrace, int& bodyStartLine);
-    int isBinaryOperator(JSTokenType token);
+    ALWAYS_INLINE int isBinaryOperator(JSTokenType token);
     bool allowAutomaticSemicolon();
 
@@ -1030 +1032 @@
 }
 
-static bool isUnaryOp(JSTokenType token)
-{
-    switch (token) {
-    case EXCLAMATION:
-    case TILDE:
-    case MINUS:
-    case PLUS:
-    case PLUSPLUS:
-    case AUTOPLUSPLUS:
-    case MINUSMINUS:
-    case AUTOMINUSMINUS:
-    case TYPEOF:
-    case VOIDTOKEN:
-    case DELETETOKEN:
-        return true;
-    default:
-        return false;
-    }
+ALWAYS_INLINE static bool isUnaryOp(JSTokenType token)
+{
+    return token & UnaryOpTokenFlag;
 }
 
 int JSParser::isBinaryOperator(JSTokenType token)
 {
-    switch (token) {
-    case OR:
-        return 1;
-
-    case AND:
-        return 2;
-
-    case BITOR:
-        return 3;
-
-    case BITXOR:
-        return 4;
-
-    case BITAND:
-        return 5;
-
-    case EQEQ:
-    case NE:
-    case STREQ:
-    case STRNEQ:
-        return 6;
-
-    case LT:
-    case GT:
-    case LE:
-    case GE:
-    case INSTANCEOF:
-        return 7;
-
-    case INTOKEN:
-        // same precedence as the above but needs a validity check
-        if (m_allowsIn)
-            return 7;
-        return 0;
-
-    case LSHIFT:
-    case RSHIFT:
-    case URSHIFT:
-        return 8;
-
-    case PLUS:
-    case MINUS:
-        return 9;
-
-    case TIMES:
-    case DIVIDE:
-    case MOD:
-        return 10;
-
-    default:
-        return 0;
-    }
+    if (m_allowsIn)
+        return token & (BinaryOpTokenPrecedenceMask << BinaryOpTokenAllowsInPrecedenceAdditionalShift);
+    return token & BinaryOpTokenPrecedenceMask;
 }