diff --git a/clang/lib/CodeGen/CGExprScalar.cpp b/clang/lib/CodeGen/CGExprScalar.cpp
index 7529d4465f2c..af89b427531d 100644
--- a/clang/lib/CodeGen/CGExprScalar.cpp
+++ b/clang/lib/CodeGen/CGExprScalar.cpp
@@ -4447,6 +4447,9 @@ Value *ScalarExprEmitter::EmitSub(const BinOpInfo &op) {
     divisor = CGF.CGM.getSize(elementSize);
   }
 
+  // With -fms-kernel we emit normal sdiv to mitigate UB.
+  if (CGF.getLangOpts().Kernel)
+    return Builder.CreateSDiv(diffInChars, divisor, "sub.ptr.div");
   // Otherwise, do a full sdiv. This uses the "exact" form of sdiv, since
   // pointer difference in C is only defined in the case where both operands
   // are pointing to elements of an array.
diff --git a/clang/test/CodeGen/MSKernel/subptr.c b/clang/test/CodeGen/MSKernel/subptr.c
new file mode 100644
index 000000000000..13079bb840a5
--- /dev/null
+++ b/clang/test/CodeGen/MSKernel/subptr.c
@@ -0,0 +1,13 @@
+// RUN: %clang_cc1 -fms-kernel -triple x86_64-windows-msvc -O2 -emit-llvm %s -o - | FileCheck %s
+// CHECK:      define {{.*}} i64 @sub_ptrs(ptr noundef %p1, ptr noundef %p2)
+// CHECK-NEXT: entry:
+// CHECK-NEXT:  %sub.ptr.lhs.cast = ptrtoint ptr %p1 to i64
+// CHECK-NEXT:  %sub.ptr.rhs.cast = ptrtoint ptr %p2 to i64
+// CHECK-NEXT:  %sub.ptr.sub = sub i64 %sub.ptr.lhs.cast, %sub.ptr.rhs.cast
+// CHECK-NEXT:  %sub.ptr.div = sdiv i64 %sub.ptr.sub, 4
+// CHECK-NEXT:  ret i64 %sub.ptr.div
+
+long long sub_ptrs(int* p1, int* p2) {
+  return p1 - p2;
+}
+