Revert of Internalize strings in-place

src/ppc/codegen-ppc.cc

Index: src/ppc/codegen-ppc.cc
diff --git a/src/ppc/codegen-ppc.cc b/src/ppc/codegen-ppc.cc
index 9109ca3fca6c80ee7487d070ec7f93e4e7740ff8..bb365b4e632b56ad25729d71f7e55ca3b5b2ffae 100644
--- a/src/ppc/codegen-ppc.cc
+++ b/src/ppc/codegen-ppc.cc
@@ -86,13 +86,11 @@
   __ andi(r0, result, Operand(kIsIndirectStringMask));
   __ beq(&check_sequential, cr0);
 
-  // Dispatch on the indirect string shape: slice or cons or thin.
-  Label cons_string, thin_string;
-  __ andi(ip, result, Operand(kStringRepresentationMask));
-  __ cmpi(ip, Operand(kConsStringTag));
-  __ beq(&cons_string);
-  __ cmpi(ip, Operand(kThinStringTag));
-  __ beq(&thin_string);
+  // Dispatch on the indirect string shape: slice or cons.
+  Label cons_string;
+  __ mov(ip, Operand(kSlicedNotConsMask));
+  __ and_(r0, result, ip, SetRC);
+  __ beq(&cons_string, cr0);
 
   // Handle slices.
   Label indirect_string_loaded;
@@ -100,11 +98,6 @@
   __ LoadP(string, FieldMemOperand(string, SlicedString::kParentOffset));
   __ SmiUntag(ip, result);
   __ add(index, index, ip);
-  __ b(&indirect_string_loaded);
-
-  // Handle thin strings.
-  __ bind(&thin_string);
-  __ LoadP(string, FieldMemOperand(string, ThinString::kActualOffset));
   __ b(&indirect_string_loaded);
 
   // Handle cons strings.