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diff --git a/tests/codegen/issues/issue-96497-slice-size-nowrap.rs b/tests/codegen/issues/issue-96497-slice-size-nowrap.rs
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+// This test case checks that LLVM is aware that computing the size of a slice cannot wrap.
+// The possibility of wrapping results in an additional branch when dropping boxed slices
+// in some situations, see https://github.com/rust-lang/rust/issues/96497#issuecomment-1112865218
+
+// compile-flags: -O
+// min-llvm-version: 15.0
+
+#![crate_type="lib"]
+
+// CHECK-LABEL: @simple_size_of_nowrap
+#[no_mangle]
+pub fn simple_size_of_nowrap(x: &[u32]) -> usize {
+ // Make sure the shift used to compute the size has a nowrap flag.
+
+ // CHECK: [[A:%.*]] = shl nsw {{.*}}, 2
+ // CHECK-NEXT: ret {{.*}} [[A]]
+ core::mem::size_of_val(x)
+}
+
+// CHECK-LABEL: @drop_write
+#[no_mangle]
+pub fn drop_write(mut x: Box<[u32]>) {
+ // Check that this write is optimized out.
+ // This depends on the size calculation not wrapping,
+ // since otherwise LLVM can't tell that the memory is always deallocated if the slice len > 0.
+
+ // CHECK-NOT: store i32 42
+ x[1] = 42;
+}