Some string optimizations:

src/macros.py

Index: src/macros.py
diff --git a/src/macros.py b/src/macros.py
index c160b4916842a456631c0b4a1adb07ff2c53ff59..94c97a7c27b6a2234c7cf5b1e712a9c82b02ae99 100644
--- a/src/macros.py
+++ b/src/macros.py
@@ -74,6 +74,10 @@ const kYearShift          = 9;
 const kMonthShift         = 5;
 
 # Type query macros.
+#
+# Note: We have special support for typeof(foo) === 'bar' in the compiler.
+#       It will *not* generate a runtime typeof call for the most important
+#       values of 'bar'.
 macro IS_NULL(arg)              = (arg === null);
 macro IS_NULL_OR_UNDEFINED(arg) = (arg == null);
 macro IS_UNDEFINED(arg)         = (typeof(arg) === 'undefined');
@@ -83,7 +87,7 @@ macro IS_BOOLEAN(arg)           = (typeof(arg) === 'boolean');
 macro IS_OBJECT(arg)            = (%_IsObject(arg));
 macro IS_ARRAY(arg)             = (%_IsArray(arg));
 macro IS_FUNCTION(arg)          = (%_IsFunction(arg));
-macro IS_REGEXP(arg)            = (%_ClassOf(arg) === 'RegExp');
+macro IS_REGEXP(arg)            = (%_IsRegExp(arg));
 macro IS_DATE(arg)              = (%_ClassOf(arg) === 'Date');
 macro IS_NUMBER_WRAPPER(arg)    = (%_ClassOf(arg) === 'Number');
 macro IS_STRING_WRAPPER(arg)    = (%_ClassOf(arg) === 'String');
@@ -100,6 +104,8 @@ macro NUMBER_IS_NAN(arg) = (!%_IsSmi(%IS_VAR(arg)) && !(arg == arg));
 macro TO_INTEGER(arg)    = (%_IsSmi(%IS_VAR(arg)) ? arg : ToInteger(arg));
 macro TO_INT32(arg)      = (%_IsSmi(%IS_VAR(arg)) ? arg : (arg >> 0));
 macro TO_UINT32(arg)     = (arg >>> 0);
+macro TO_STRING_INLINE(arg)     = (IS_STRING(%IS_VAR(arg)) ? arg : NonStringToString(arg));

[Mads Ager (chromium), 2010/02/19 09:56:29]

Remove extra spaces before '=' on this line.  I would be in favor of removing
all of the alignment whitespace here, but you don't have to do that in this
change.

[Vitaly Repeshko, 2010/02/19 13:12:35]

Done.

+
 
 # Macros implemented in Python.
 python macro CHAR_CODE(str) = ord(str[1]);