[csa|interpreter] Remove unnecessary SMI tagging.

Bug: 
Change-Id: Ic872ea78511f0ef3e8cea67b971162b71790a039
Reviewed-on: https://chromium-review.googlesource.com/781690Reviewed-by: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Igor Sheludko <ishell@chromium.org>
Commit-Queue: Marja Hölttä <marja@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49564}

src/code-stub-assembler.cc

@@ -7978,7 +7978,7 @@ Node* CodeStubAssembler::CreateWeakCellInFeedbackVector(Node* feedback_vector,
 
   // Store the WeakCell in the feedback vector.
   StoreFeedbackVectorSlot(feedback_vector, slot, cell, UPDATE_WRITE_BARRIER, 0,
-                          CodeStubAssembler::SMI_PARAMETERS);
+                          CodeStubAssembler::INTPTR_PARAMETERS);
   return cell;
 }
 

src/interpreter/interpreter-assembler.cc

@@ -668,7 +668,7 @@ void InterpreterAssembler::CollectCallableFeedback(Node* target, Node* context,
         }
       }
       BIND(&done_loop);
-      CreateWeakCellInFeedbackVector(feedback_vector, SmiTag(slot_id), target);
+      CreateWeakCellInFeedbackVector(feedback_vector, slot_id, target);
       ReportFeedbackUpdate(feedback_vector, slot_id, "Call:Initialize");
       Goto(&done);
     }
@@ -875,8 +875,7 @@ Node* InterpreterAssembler::Construct(Node* target, Node* context,
 
       BIND(&create_weak_cell);
       {
-        CreateWeakCellInFeedbackVector(feedback_vector, SmiTag(slot_id),
-                                       new_target);
+        CreateWeakCellInFeedbackVector(feedback_vector, slot_id, new_target);
         ReportFeedbackUpdate(feedback_vector, slot_id,
                              "Construct:CreateWeakCell");
         Goto(&construct);
@@ -994,8 +993,7 @@ Node* InterpreterAssembler::ConstructWithSpread(Node* target, Node* context,
       GotoIfNot(WordEqual(LoadNativeContext(context), target_native_context),
                 &mark_megamorphic);
 
-      CreateWeakCellInFeedbackVector(feedback_vector, SmiTag(slot_id),
-                                     new_target);
+      CreateWeakCellInFeedbackVector(feedback_vector, slot_id, new_target);
       ReportFeedbackUpdate(feedback_vector, slot_id,
                            "ConstructWithSpread:Initialize");
       Goto(&construct);