1148   Environment* slow_environment = nullptr;  in CheckContextExtensions()  local
1167       if (slow_environment == nullptr) {  in CheckContextExtensions()
1168         slow_environment = environment();  in CheckContextExtensions()
1171         slow_environment->Merge(environment(),  in CheckContextExtensions()
1184   DCHECK(depth == 0 || slow_environment != nullptr);  in CheckContextExtensions()
1186   return slow_environment;  in CheckContextExtensions()
1193   Environment* slow_environment = CheckContextExtensions(depth);  in BuildLdaLookupContextSlot()  local
1204   if (slow_environment != nullptr) {  in BuildLdaLookupContextSlot()
1210     set_environment(slow_environment);  in BuildLdaLookupContextSlot()
1243   Environment* slow_environment = CheckContextExtensions(depth);  in BuildLdaLookupGlobalSlot()  local
1257   if (slow_environment != nullptr) {  in BuildLdaLookupGlobalSlot()
1263     set_environment(slow_environment);  in BuildLdaLookupGlobalSlot()