diff --git a/llvm/lib/Transforms/IPO/OpenMPOpt.cpp b/llvm/lib/Transforms/IPO/OpenMPOpt.cpp
--- a/llvm/lib/Transforms/IPO/OpenMPOpt.cpp
+++ b/llvm/lib/Transforms/IPO/OpenMPOpt.cpp
@@ -2119,6 +2119,8 @@
                                        OMPRTL___kmpc_barrier_simple_generic);
     ExternalizationRAII ThreadId(OMPInfoCache,
                                  OMPRTL___kmpc_get_hardware_thread_id_in_block);
+    ExternalizationRAII NumThreads(
+        OMPInfoCache, OMPRTL___kmpc_get_hardware_num_threads_in_block);
     ExternalizationRAII WarpSize(OMPInfoCache, OMPRTL___kmpc_get_warp_size);
 
     registerAAs(IsModulePass);
diff --git a/llvm/test/Transforms/OpenMP/get_hardware_num_threads_in_block_fold.ll b/llvm/test/Transforms/OpenMP/get_hardware_num_threads_in_block_fold.ll
--- a/llvm/test/Transforms/OpenMP/get_hardware_num_threads_in_block_fold.ll
+++ b/llvm/test/Transforms/OpenMP/get_hardware_num_threads_in_block_fold.ll
@@ -178,7 +178,16 @@
   ret void
 }
 
-declare i32 @__kmpc_get_hardware_num_threads_in_block()
+define internal i32 @__kmpc_get_hardware_num_threads_in_block() {
+; CHECK-LABEL: define {{[^@]+}}@__kmpc_get_hardware_num_threads_in_block
+; CHECK-SAME: () #[[ATTR1]] {
+; CHECK-NEXT:    [[RET:%.*]] = call i32 @__kmpc_get_hardware_num_threads_in_block_dummy()
+; CHECK-NEXT:    ret i32 [[RET]]
+;
+  %ret = call i32 @__kmpc_get_hardware_num_threads_in_block_dummy()
+  ret i32 %ret
+}
+declare i32 @__kmpc_get_hardware_num_threads_in_block_dummy()
 declare i32 @__kmpc_target_init(%struct.ident_t*, i8, i1 zeroext, i1 zeroext) #1
 declare void @__kmpc_target_deinit(%struct.ident_t* nocapture readnone, i8, i1 zeroext) #1
 declare void @__kmpc_parallel_51(%struct.ident_t*, i32, i32, i32, i32, i8*, i8*, i8**, i64)