diff --git a/llvm/test/tools/llvm-reduce/thinlto-preserve-uselistorder.ll b/llvm/test/tools/llvm-reduce/thinlto-preserve-uselistorder.ll
index 2332f2d632911..eac3e462aab8a 100644
--- a/llvm/test/tools/llvm-reduce/thinlto-preserve-uselistorder.ll
+++ b/llvm/test/tools/llvm-reduce/thinlto-preserve-uselistorder.ll
@@ -1,19 +1,48 @@
-; RUN: opt --thinlto-bc --thinlto-split-lto-unit %s -o %t.0
-; RUN: llvm-reduce -write-tmp-files-as-bitcode --delta-passes=instructions %t.0 -o %t.1 \
+; RUN: opt --preserve-bc-uselistorder --thinlto-bc --thinlto-split-lto-unit %s -o %t.0
+
+; RUN: llvm-reduce -j=2 --delta-passes=instructions %t.0 -o %t.1 \
 ; RUN:     --test %python --test-arg %p/Inputs/llvm-dis-and-filecheck.py --test-arg llvm-dis --test-arg FileCheck --test-arg --check-prefix=INTERESTING --test-arg %s
 ; RUN: llvm-dis --preserve-ll-uselistorder %t.1 -o %t.2
-; RUN: FileCheck --check-prefix=RESULT %s < %t.2
-
-define i32 @func(i32 %arg0, i32 %arg1) {
-entry:
-  %add0 = add i32 %arg0, 0
-  %add1 = add i32 %add0, 0
-  %add2 = add i32 %add1, 0
-  %add3 = add i32 %arg1, 0
-  %add4 = add i32 %add2, %add3
-  ret i32 %add4
+; RUN: FileCheck --check-prefixes=RESULT,RESULT-PARALLEL %s < %t.2
+
+; FIXME: The single thread path uses CloneModule, which does not
+; preserve uselistorder. Consequently it is incapable of reducing
+; anything a case that depends on uselistorder.
+
+; RUN: llvm-reduce -j=1 --delta-passes=instructions %t.0 -o %t.3 \
+; RUN:     --test %python --test-arg %p/Inputs/llvm-dis-and-filecheck.py --test-arg llvm-dis --test-arg FileCheck --test-arg --check-prefix=INTERESTING --test-arg %s
+; RUN: llvm-dis --preserve-ll-uselistorder %t.3 -o %t.4
+; RUN: FileCheck --check-prefixes=RESULT,RESULT-SINGLE %s < %t.4
+
+@gv0 = external global [0 x i8]
+
+; RESULT-LABEL: @func(
+; RESULT-PARALLEL-NEXT: %gep0 = getelementptr i8, ptr @gv0, i32 %arg0
+; RESULT-PARALLEL-NEXT: %gep1 = getelementptr i8, ptr @gv0, i32 %arg1
+; RESULT-PARALLEL-NEXT: ret void
+
+; RESULT-SINGLE: ptr @gv0
+; RESULT-SINGLE: ptr @gv0
+; RESULT-SINGLE: ptr @gv0
+; RESULT-SINGLE: ptr @gv0
+; RESULT-SINGLE: ptr @gv0
+define void @func(i32 %arg0, i32 %arg1, i32 %arg2, i32 %arg3) {
+  %gep0 = getelementptr i8, ptr @gv0, i32 %arg0
+  %gep1 = getelementptr i8, ptr @gv0, i32 %arg1
+  %gep2 = getelementptr i8, ptr @gv0, i32 %arg2
+  %gep3 = getelementptr i8, ptr @gv0, i32 %arg3
+  store i32 0, ptr %gep0
+  store i32 0, ptr %gep1
+  store i32 0, ptr %gep2
+  store i32 0, ptr %gep3
+  store i32 0, ptr @gv0
+  ret void
 }
 
-; INTERESTING: uselistorder i32 0
-; RESULT: uselistorder i32 0, { 0, 2, 1 }
-uselistorder i32 0, { 3, 2, 1, 0 }
+; INTERESTING: uselistorder ptr
+
+; RESULT: uselistorder directives
+; RESULT-PARALLEL: uselistorder ptr @gv0, { 1, 0 }
+; RESULT-SINGLE: uselistorder ptr @gv0, { 3, 4, 2, 1, 0 }
+
+uselistorder ptr @gv0, { 3, 4, 2, 1, 0 }