Reshuffle registers in JSConstructStub to avoid trashing costructor and new.target on fast path (so…

src/ia32/builtins-ia32.cc

Index: src/ia32/builtins-ia32.cc
diff --git a/src/ia32/builtins-ia32.cc b/src/ia32/builtins-ia32.cc
index 3d129df428a4172a35ae02a1f7dfacc9b4d36a46..c5448b688252484083722ce0ab7a0a8b03c5fd98 100644
--- a/src/ia32/builtins-ia32.cc
+++ b/src/ia32/builtins-ia32.cc
@@ -251,8 +251,10 @@ static void Generate_JSConstructStubHelper(MacroAssembler* masm,
                       kUnexpectedNumberOfPreAllocatedPropertyFields);
           }
           __ InitializeFieldsWithFiller(ecx, esi, edx);
+
+          // To allow truncation fill the remaining fields with one pointer
+          // filler map.
           __ mov(edx, factory->one_pointer_filler_map());
-          // Fill the remaining fields with one pointer filler map.
 
           __ bind(&no_inobject_slack_tracking);
         }