Index: llvm/test/tools/llvm-reduce/no-remove-ifunc-function.ll
===================================================================
--- /dev/null
+++ llvm/test/tools/llvm-reduce/no-remove-ifunc-function.ll
@@ -0,0 +1,27 @@
+; RUN: llvm-reduce -abort-on-invalid-reduction --delta-passes=functions --test FileCheck --test-arg --check-prefixes=CHECK-INTERESTINGNESS --test-arg %s --test-arg --input-file %s -o %t
+; RUN: FileCheck --check-prefixes=CHECK-FINAL --input-file=%t %s
+
+; Test handling of ifunc. Make sure function reduction doesn't create
+; invalid ifunc
+
+
+; CHECK-INTERESTINGNESS: define void @no_ifunc_interesting
+
+; CHECK-FINAL: @ifunc1 = ifunc void (), ptr @has_ifunc
+; CHECK-FINAL: define void @no_ifunc_interesting() {
+; CHECK-FINAL-NOT: define
+
+@ifunc1 = ifunc void (), ptr @has_ifunc
+
+
+define void @has_ifunc() {
+  ret void
+}
+
+define void @no_ifunc_interesting() {
+  ret void
+}
+
+define void @no_ifunc_boring() {
+  ret void
+}
Index: llvm/tools/llvm-reduce/deltas/Utils.cpp
===================================================================
--- llvm/tools/llvm-reduce/deltas/Utils.cpp
+++ llvm/tools/llvm-reduce/deltas/Utils.cpp
@@ -13,6 +13,7 @@
 #include "Utils.h"
 #include "llvm/IR/Constants.h"
 #include "llvm/IR/GlobalAlias.h"
+#include "llvm/IR/GlobalIFunc.h"
 
 using namespace llvm;
 
@@ -27,5 +28,7 @@
 }
 
 bool llvm::hasAliasUse(Function &F) {
-  return any_of(F.users(), [](User *U) { return isa<GlobalAlias>(U); });
+  return any_of(F.users(), [](User *U) {
+      return isa<GlobalAlias>(U) || isa<GlobalIFunc>(U);
+    });
 }