[runtime] Store constructor function index on primitive maps.

src/ppc/builtins-ppc.cc

Index: src/ppc/builtins-ppc.cc
diff --git a/src/ppc/builtins-ppc.cc b/src/ppc/builtins-ppc.cc
index 45a6c9ea694d6a5b0f00bb90a07d9325ece2cb6b..0bc781e34c005ceecf3aec2936553a5bc3eedce2 100644
--- a/src/ppc/builtins-ppc.cc
+++ b/src/ppc/builtins-ppc.cc
@@ -434,7 +434,10 @@ static void Generate_JSConstructStubHelper(MacroAssembler* masm,
         __ blt(&no_inobject_slack_tracking);
 
         // Allocate object with a slack.
-        __ lbz(r3, FieldMemOperand(r5, Map::kInObjectPropertiesOffset));
+        __ lbz(
+            r3,
+            FieldMemOperand(
+                r5, Map::kInObjectPropertiesOrConstructorFunctionIndexOffset));
         __ lbz(r5, FieldMemOperand(r5, Map::kUnusedPropertyFieldsOffset));
         __ sub(r3, r3, r5);
         if (FLAG_debug_code) {