diff --git a/llvm/test/Transforms/InstSimplify/constant-fold-inttoptr-add.ll b/llvm/test/Transforms/InstSimplify/constant-fold-inttoptr-add.ll
new file mode 100644
index 000000000000..59b415741024
--- /dev/null
+++ b/llvm/test/Transforms/InstSimplify/constant-fold-inttoptr-add.ll
@@ -0,0 +1,101 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+; RUN: opt -p instcombine -S %s | FileCheck %s
+
+@glob = external global [314 x i64]
+
+define i1 @known_constexpr_add_eq() {
+; CHECK-LABEL: define i1 @known_constexpr_add_eq() {
+; CHECK-NEXT:    [[COND:%.*]] = icmp eq ptr getelementptr inbounds nuw (i8, ptr @glob, i64 80), inttoptr (i64 add (i64 ptrtoint (ptr @glob to i64), i64 -80) to ptr)
+; CHECK-NEXT:    ret i1 [[COND]]
+;
+  %cond = icmp eq ptr getelementptr inbounds nuw (i8, ptr @glob, i64 80), inttoptr (i64 add (i64 ptrtoint (ptr @glob to i64), i64 -80) to ptr)
+  ret i1 %cond
+}
+
+define i1 @known_constexpr_add_eq_ops_swapped() {
+; CHECK-LABEL: define i1 @known_constexpr_add_eq_ops_swapped() {
+; CHECK-NEXT:    [[COND:%.*]] = icmp eq ptr getelementptr inbounds nuw (i8, ptr @glob, i64 80), inttoptr (i64 add (i64 ptrtoint (ptr @glob to i64), i64 -80) to ptr)
+; CHECK-NEXT:    ret i1 [[COND]]
+;
+  %cond = icmp eq ptr getelementptr inbounds nuw (i8, ptr @glob, i64 80), inttoptr (i64 add (i64 ptrtoint (ptr @glob to i64), i64 -80) to ptr)
+  ret i1 %cond
+}
+
+define i1 @known_constexpr_add_ne() {
+; CHECK-LABEL: define i1 @known_constexpr_add_ne() {
+; CHECK-NEXT:    [[COND:%.*]] = icmp ne ptr getelementptr inbounds nuw (i8, ptr @glob, i64 80), inttoptr (i64 add (i64 ptrtoint (ptr @glob to i64), i64 -80) to ptr)
+; CHECK-NEXT:    ret i1 [[COND]]
+;
+  %cond = icmp ne ptr getelementptr inbounds nuw (i8, ptr @glob, i64 80), inttoptr (i64 add (i64 ptrtoint (ptr @glob to i64), i64 -80) to ptr)
+  ret i1 %cond
+}
+
+define i1 @wrap_positive_to_negate() {
+; CHECK-LABEL: define i1 @wrap_positive_to_negate() {
+; CHECK-NEXT:    ret i1 false
+;
+  %cond = icmp eq ptr @glob, inttoptr (i64 add (i64 ptrtoint (ptr getelementptr nuw (i8, ptr @glob, i64 1)to i64), i64 9223372036854775808) to ptr)
+  ret i1 %cond
+}
+
+; 9223372036854775808 = 2^63
+define i1 @wrap_positive_to_zero() {
+; CHECK-LABEL: define i1 @wrap_positive_to_zero() {
+; CHECK-NEXT:    [[COND:%.*]] = icmp eq ptr @glob, inttoptr (i64 add (i64 ptrtoint (ptr getelementptr nuw (i8, ptr @glob, i64 -9223372036854775808) to i64), i64 -9223372036854775808) to ptr)
+; CHECK-NEXT:    ret i1 [[COND]]
+;
+  %cond = icmp eq ptr @glob, inttoptr (i64 add (i64 ptrtoint (ptr getelementptr nuw (i8, ptr @glob, i64 9223372036854775808)to i64), i64 9223372036854775808) to ptr)
+  ret i1 %cond
+}
+
+define i1 @not_known_constexpr_add_sle() {
+; CHECK-LABEL: define i1 @not_known_constexpr_add_sle() {
+; CHECK-NEXT:    [[COND:%.*]] = icmp sle ptr @glob, inttoptr (i64 add (i64 ptrtoint (ptr @glob to i64), i64 -80) to ptr)
+; CHECK-NEXT:    ret i1 [[COND]]
+;
+  %cond = icmp sle ptr @glob, inttoptr (i64 add (i64 ptrtoint (ptr @glob to i64), i64 -80) to ptr)
+  ret i1 %cond
+}
+
+define i1 @not_known_constexpr_add_ule() {
+; CHECK-LABEL: define i1 @not_known_constexpr_add_ule() {
+; CHECK-NEXT:    [[COND:%.*]] = icmp ule ptr @glob, inttoptr (i64 add (i64 ptrtoint (ptr @glob to i64), i64 -80) to ptr)
+; CHECK-NEXT:    ret i1 [[COND]]
+;
+  %cond = icmp ule ptr @glob, inttoptr (i64 add (i64 ptrtoint (ptr @glob to i64), i64 -80) to ptr)
+  ret i1 %cond
+}
+
+define i1 @not_known_constexpr_add_sge() {
+; CHECK-LABEL: define i1 @not_known_constexpr_add_sge() {
+; CHECK-NEXT:    [[COND:%.*]] = icmp sge ptr @glob, inttoptr (i64 add (i64 ptrtoint (ptr @glob to i64), i64 -80) to ptr)
+; CHECK-NEXT:    ret i1 [[COND]]
+;
+  %cond = icmp sge ptr @glob, inttoptr (i64 add (i64 ptrtoint (ptr @glob to i64), i64 -80) to ptr)
+  ret i1 %cond
+}
+
+define i1 @not_known_constexpr_add_uge() {
+; CHECK-LABEL: define i1 @not_known_constexpr_add_uge() {
+; CHECK-NEXT:    [[COND:%.*]] = icmp uge ptr @glob, inttoptr (i64 add (i64 ptrtoint (ptr @glob to i64), i64 -80) to ptr)
+; CHECK-NEXT:    ret i1 [[COND]]
+;
+  %cond = icmp uge ptr @glob, inttoptr (i64 add (i64 ptrtoint (ptr @glob to i64), i64 -80) to ptr)
+  ret i1 %cond
+}
+
+define i1 @not_known_integer_width_does_not_match_pointer_index_width() {
+; CHECK-LABEL: define i1 @not_known_integer_width_does_not_match_pointer_index_width() {
+; CHECK-NEXT:    [[COND:%.*]] = icmp eq ptr getelementptr inbounds nuw (i8, ptr @glob, i64 80), inttoptr (i32 add (i32 ptrtoint (ptr @glob to i32), i32 -80) to ptr)
+; CHECK-NEXT:    ret i1 [[COND]]
+;
+  %cond = icmp eq ptr getelementptr inbounds nuw (i8, ptr @glob, i64 80), inttoptr (i32 add (i32 ptrtoint (ptr @glob to i32), i32 -80) to ptr)
+  ret i1 %cond
+}
+
+define ptr @return_inttoptr() {
+; CHECK-LABEL: define ptr @return_inttoptr() {
+; CHECK-NEXT:    ret ptr inttoptr (i64 add (i64 ptrtoint (ptr @glob to i64), i64 8) to ptr)
+;
+  ret ptr inttoptr (i64 add (i64 ptrtoint (ptr @glob to i64), i64 8) to ptr)
+}