Skip the mapcheck on the global object since the global proxy and cell are already checked (or the …

src/ic/arm64/handler-compiler-arm64.cc

Index: src/ic/arm64/handler-compiler-arm64.cc
diff --git a/src/ic/arm64/handler-compiler-arm64.cc b/src/ic/arm64/handler-compiler-arm64.cc
index 53519179f269d54e7d307bbc9ce2189d4320931c..de1b9f598fee07449ac1aa4adb674d3d2a4cf8f2 100644
--- a/src/ic/arm64/handler-compiler-arm64.cc
+++ b/src/ic/arm64/handler-compiler-arm64.cc
@@ -523,15 +523,13 @@ Register PropertyHandlerCompiler::CheckPrototypes(
       Register map_reg = scratch1;
       __ Ldr(map_reg, FieldMemOperand(reg, HeapObject::kMapOffset));
 
-      if (depth != 1 || check == CHECK_ALL_MAPS) {
-        Handle<WeakCell> cell = Map::WeakCellForMap(current_map);
-        __ CmpWeakValue(map_reg, cell, scratch2);
-        __ B(ne, miss);
-      }
-
       if (current_map->IsJSGlobalObjectMap()) {
         GenerateCheckPropertyCell(masm(), Handle<JSGlobalObject>::cast(current),
                                   name, scratch2, miss);
+      } else if (depth != 1 || check == CHECK_ALL_MAPS) {
+        Handle<WeakCell> cell = Map::WeakCellForMap(current_map);
+        __ CmpWeakValue(map_reg, cell, scratch2);
+        __ B(ne, miss);
       }
 
       reg = holder_reg;  // From now on the object will be in holder_reg.
@@ -544,6 +542,8 @@ Register PropertyHandlerCompiler::CheckPrototypes(
     current_map = handle(current->map());
   }
 
+  DCHECK(!current_map->IsJSGlobalProxyMap());
+
   // Log the check depth.
   LOG(isolate(), IntEvent("check-maps-depth", depth + 1));