Remove unnecessary conditions around Map::AsElementsKind calls.

Map::AsElementsKind returns the given map if it already has the desired
elements kind.

Change-Id: Ia9c92eabdb28c82da376eb87f0117dc76414240d
Reviewed-on: https://chromium-review.googlesource.com/1164368Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Georg Neis <neis@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54941}

src/compiler/js-create-lowering.cc

@@ -489,10 +489,8 @@ Reduction JSCreateLowering::ReduceNewArray(Node* node, Node* length,
 
   // Constructing an Array via new Array(N) where N is an unsigned
   // integer, always creates a holey backing store.
-  if (!IsHoleyElementsKind(initial_map.elements_kind())) {
-    initial_map = initial_map.AsElementsKind(
-        GetHoleyElementsKind(initial_map.elements_kind()));
-  }
+  initial_map = initial_map.AsElementsKind(
+      GetHoleyElementsKind(initial_map.elements_kind()));
 
   // Check that the {limit} is an unsigned integer in the valid range.
   // This has to be kept in sync with src/runtime/runtime-array.cc,
@@ -733,9 +731,7 @@ Reduction JSCreateLowering::ReduceJSCreateArray(Node* node) {
       // Check if we have a feedback {site} on the {node}.
       if (site_ref) {
         ElementsKind elements_kind = site_ref->GetElementsKind();
-        if (initial_map.elements_kind() != elements_kind) {
-          initial_map = initial_map.AsElementsKind(elements_kind);
-        }
+        initial_map = initial_map.AsElementsKind(elements_kind);
         can_inline_call = site_ref->CanInlineCall();
         pretenure = dependencies()->DependOnPretenureMode(*site_ref);
         dependencies()->DependOnElementsKind(*site_ref);

src/map-updater.cc

@@ -245,9 +245,7 @@ MapUpdater::State MapUpdater::FindRootMap() {
     state_ = kEnd;
     result_map_ = handle(
         JSFunction::cast(root_map_->GetConstructor())->initial_map(), isolate_);
-    if (from_kind != to_kind) {
-      result_map_ = Map::AsElementsKind(isolate_, result_map_, to_kind);
-    }
+    result_map_ = Map::AsElementsKind(isolate_, result_map_, to_kind);
     DCHECK(result_map_->is_dictionary_map());
     return state_;
   }
@@ -307,9 +305,7 @@ MapUpdater::State MapUpdater::FindRootMap() {
   }
 
   // From here on, use the map with correct elements kind as root map.
-  if (from_kind != to_kind) {
-    root_map_ = Map::AsElementsKind(isolate_, root_map_, to_kind);
-  }
+  root_map_ = Map::AsElementsKind(isolate_, root_map_, to_kind);
   state_ = kAtRootMap;
   return state_;  // Not done yet.
 }

src/runtime/runtime-array.cc

@@ -599,9 +599,7 @@ RUNTIME_FUNCTION(Runtime_NewArray) {
   // We should allocate with an initial map that reflects the allocation site
   // advice. Therefore we use AllocateJSObjectFromMap instead of passing
   // the constructor.
-  if (to_kind != initial_map->elements_kind()) {
-    initial_map = Map::AsElementsKind(isolate, initial_map, to_kind);
-  }
+  initial_map = Map::AsElementsKind(isolate, initial_map, to_kind);
 
   // If we don't care to track arrays of to_kind ElementsKind, then
   // don't emit a memento for them.