Remove the different length string types...

src/ia32/codegen-ia32.cc

Index: src/ia32/codegen-ia32.cc
===================================================================
--- src/ia32/codegen-ia32.cc	(revision 3336)
+++ src/ia32/codegen-ia32.cc	(working copy)
@@ -4777,18 +4777,8 @@
   __ test(ecx, Immediate(kIsNotStringMask));
   __ j(not_zero, &slow_case);
 
-  // Here we make assumptions about the tag values and the shifts needed.
-  // See the comment in objects.h.
-  ASSERT(kLongStringTag == 0);
-  ASSERT(kMediumStringTag + String::kLongLengthShift ==
-         String::kMediumLengthShift);
-  ASSERT(kShortStringTag + String::kLongLengthShift ==
-         String::kShortLengthShift);
-  __ and_(ecx, kStringSizeMask);
-  __ add(Operand(ecx), Immediate(String::kLongLengthShift));
   // Fetch the length field into the temporary register.
   __ mov(temp.reg(), FieldOperand(object.reg(), String::kLengthOffset));
-  __ shr_cl(temp.reg());
   // Check for index out of range.
   __ cmp(index.reg(), Operand(temp.reg()));
   __ j(greater_equal, &slow_case);
@@ -6502,11 +6492,8 @@
   // String value => false iff empty.
   __ cmp(ecx, FIRST_NONSTRING_TYPE);
   __ j(above_equal, &not_string);
-  __ and_(ecx, kStringSizeMask);
-  __ cmp(ecx, kShortStringTag);
-  __ j(not_equal, &true_result);  // Empty string is always short.
   __ mov(edx, FieldOperand(eax, String::kLengthOffset));
-  __ shr(edx, String::kShortLengthShift);
+  __ test(edx, Operand(edx));
   __ j(zero, &false_result);
   __ jmp(&true_result);