From cd5f228acd214c0a6555756b060dd0223d31050d Mon Sep 17 00:00:00 2001
From: Alex Gaynor <alex.gaynor@gmail.com>
Date: Sun, 24 May 2020 16:20:02 -0400
Subject: [PATCH] Added a codegen test for a recent optimization for
 overflow-checks=on

Closes #58692
---
 src/test/codegen/integer-overflow.rs | 26 ++++++++++++++++++++++++++
 1 file changed, 26 insertions(+)
 create mode 100644 src/test/codegen/integer-overflow.rs

diff --git a/src/test/codegen/integer-overflow.rs b/src/test/codegen/integer-overflow.rs
new file mode 100644
index 0000000000000..183de56db9685
--- /dev/null
+++ b/src/test/codegen/integer-overflow.rs
@@ -0,0 +1,26 @@
+// no-system-llvm
+// compile-flags: -O -C overflow-checks=on
+
+#![crate_type = "lib"]
+
+
+pub struct S1<'a> {
+    data: &'a [u8],
+    position: usize,
+}
+
+// CHECK-LABEL: @slice_no_index_order
+#[no_mangle]
+pub fn slice_no_index_order<'a>(s: &'a mut S1, n: usize) -> &'a [u8] {
+    // CHECK-NOT: slice_index_order_fail
+    let d = &s.data[s.position..s.position+n];
+    s.position += n;
+    return d;
+}
+
+// CHECK-LABEL: @test_check
+#[no_mangle]
+pub fn test_check<'a>(s: &'a mut S1, x: usize, y: usize) -> &'a [u8] {
+    // CHECK: slice_index_order_fail
+    &s.data[x..y]
+}