diff --git a/llvm/test/Reduce/Inputs/remove-multiple-use-of-global-vars-in-same-instruction.py b/llvm/test/Reduce/Inputs/remove-multiple-use-of-global-vars-in-same-instruction.py
new file mode 100644
index 00000000000000..93fa5c0bc29e7d
--- /dev/null
+++ b/llvm/test/Reduce/Inputs/remove-multiple-use-of-global-vars-in-same-instruction.py
@@ -0,0 +1,13 @@
+import sys
+
+FunctionCallPresent = False
+
+input = open(sys.argv[1], "r")
+for line in input:
+  if "call void @use" in line:
+    FunctionCallPresent = True
+
+if FunctionCallPresent:
+  sys.exit(0) # Interesting!
+
+sys.exit(1)
diff --git a/llvm/test/Reduce/remove-multiple-use-of-global-vars-in-same-instruction.ll b/llvm/test/Reduce/remove-multiple-use-of-global-vars-in-same-instruction.ll
new file mode 100644
index 00000000000000..c8b639099fd33f
--- /dev/null
+++ b/llvm/test/Reduce/remove-multiple-use-of-global-vars-in-same-instruction.ll
@@ -0,0 +1,24 @@
+; Test that llvm-reduce can remove uninteresting function arguments from function definitions as well as their calls.
+;
+; RUN: rm -rf %t
+; RUN: llvm-reduce --test %python --test-arg %p/Inputs/remove-multiple-use-of-global-vars-in-same-instruction.py %s -o %t
+; RUN: cat %t | FileCheck -implicit-check-not=uninteresting %s
+
+; CHECK: @uninteresting1 = global
+; CHECK: @uninteresting2 = global
+; CHECK: @uninteresting3 = global
+@uninteresting1 = global i32 0, align 4
+@uninteresting2 = global i32 0, align 4
+@uninteresting3 = global i32 0, align 4
+
+declare void @use(i32*, i32*, i32*)
+
+; CHECK-LABEL: @interesting()
+define void @interesting() {
+entry:
+  ; CHECK: call void @use(i32* @uninteresting1, i32* @uninteresting2, i32* @uninteresting3)
+  call void @use(i32* @uninteresting1, i32* @uninteresting2, i32* @uninteresting3)
+  call void @use(i32* @uninteresting1, i32* @uninteresting2, i32* @uninteresting3)
+  call void @use(i32* @uninteresting1, i32* @uninteresting2, i32* @uninteresting3)
+  ret void
+}
diff --git a/llvm/tools/llvm-reduce/deltas/ReduceGlobalVars.cpp b/llvm/tools/llvm-reduce/deltas/ReduceGlobalVars.cpp
index 843ca46458f504..55d732cfec98b1 100644
--- a/llvm/tools/llvm-reduce/deltas/ReduceGlobalVars.cpp
+++ b/llvm/tools/llvm-reduce/deltas/ReduceGlobalVars.cpp
@@ -33,7 +33,7 @@ static void extractGVsFromModule(std::vector<Chunk> ChunksToKeep,
 
   // Delete out-of-chunk GVs and their uses
   std::vector<GlobalVariable *> ToRemove;
-  std::vector<Instruction *> InstToRemove;
+  std::vector<WeakVH> InstToRemove;
   for (auto &GV : Program->globals())
     if (GV.hasInitializer() && !GVsToKeep.count(&GV)) {
       for (auto U : GV.users())
@@ -44,8 +44,11 @@ static void extractGVsFromModule(std::vector<Chunk> ChunksToKeep,
       ToRemove.push_back(&GV);
     }
 
-  // Delete Instruction uses of unwanted GVs
-  for (auto *Inst : InstToRemove) {
+  // Delete (unique) Instruction uses of unwanted GVs
+  for (Value *V : InstToRemove) {
+    if (!V)
+      continue;
+    auto *Inst = cast<Instruction>(V);
     Inst->replaceAllUsesWith(UndefValue::get(Inst->getType()));
     Inst->eraseFromParent();
   }