- Added %IsArrayClass, %IsDateClass, and %IsStringClass....

src/runtime.js

Index: src/runtime.js
===================================================================
--- src/runtime.js	(revision 457)
+++ src/runtime.js	(working copy)
@@ -52,36 +52,31 @@
 
 // ECMA-262, section 11.9.1, page 55.
 function EQUALS(y) {
+  if (IS_STRING(this) && IS_STRING(y)) return %StringEquals(this, y);
   var x = this;
 
   // NOTE: We use iteration instead of recursion, because it is
   // difficult to call EQUALS with the correct setting of 'this' in
   // an efficient way.
-
   while (true) {
-
     if (IS_NUMBER(x)) {
       if (y == null) return 1;  // not equal
       return %NumberEquals(x, %ToNumber(y));
-
     } else if (IS_STRING(x)) {
       if (IS_STRING(y)) return %StringEquals(x, y);
       if (IS_NUMBER(y)) return %NumberEquals(%ToNumber(x), y);
       if (IS_BOOLEAN(y)) return %NumberEquals(%ToNumber(x), %ToNumber(y));
       if (y == null) return 1;  // not equal
       y = %ToPrimitive(y, NO_HINT);
-
     } else if (IS_BOOLEAN(x)) {
       if (IS_BOOLEAN(y)) {
         return %_ObjectEquals(x, y) ? 0 : 1;
       }
       if (y == null) return 1;  // not equal
       return %NumberEquals(%ToNumber(x), %ToNumber(y));
-
     } else if (x == null) {
       // NOTE: This checks for both null and undefined.
       return (y == null) ? 0 : 1;
-
     } else {
       if (IS_OBJECT(y)) {
         return %_ObjectEquals(x, y) ? 0 : 1;
@@ -90,12 +85,10 @@
         return %_ObjectEquals(x, y) ? 0 : 1;
       }
       x = %ToPrimitive(x, NO_HINT);
-
     }
   }
 }
 
-
 // ECMA-262, section 11.9.4, page 56.
 function STRICT_EQUALS(x) {
   if (IS_NUMBER(this)) {
@@ -125,11 +118,15 @@
 // ECMA-262, section 11.8.5, page 53. The 'ncr' parameter is used as
 // the result when either (or both) the operands are NaN.
 function COMPARE(x, ncr) {
-  // Improve performance for floating point compares
+  // Fast case for numbers and strings.
   if (IS_NUMBER(this) && IS_NUMBER(x)) {
     return %NumberCompare(this, x, ncr);
   }
+  if (IS_STRING(this) && IS_STRING(x)) {
+    return %StringCompare(this, x);
+  }
 
+  // Default implementation.
   var a = %ToPrimitive(this, NUMBER_HINT);
   var b = %ToPrimitive(x, NUMBER_HINT);
   if (IS_STRING(a) && IS_STRING(b)) {
@@ -149,10 +146,10 @@
 // ECMA-262, section 11.6.1, page 50.
 function ADD(x) {
   // Fast case: Check for number operands and do the addition.
-  if (IS_NUMBER(this) && IS_NUMBER(x)) {
-    return %NumberAdd(this, x);
-  }
+  if (IS_NUMBER(this) && IS_NUMBER(x)) return %NumberAdd(this, x);
+  if (IS_STRING(this) && IS_STRING(x)) return %StringAdd(this, x);
 
+  // Default implementation.
   var a = %ToPrimitive(this, NO_HINT);
   var b = %ToPrimitive(x, NO_HINT);
   
@@ -397,6 +394,10 @@
 // ECMA-262, section 9.1, page 30. Use null/undefined for no hint,
 // (1) for number hint, and (2) for string hint.
 function ToPrimitive(x, hint) {
+  // Fast case check.
+  if (IS_STRING(x)) return x;
+  if ((hint != NUMBER_HINT) && %IsStringClass(x)) return %_ValueOf(x);
+  // Normal behaior.
   if (!IS_OBJECT(x) && !IS_FUNCTION(x)) return x;
   if (x == null) return x;  // check for null, undefined
   if (hint == NO_HINT) hint = (IS_DATE(x)) ? STRING_HINT : NUMBER_HINT;