Allow MaybeUninit in input and output of inline assembly

1 files changed, 27 insertions, 0 deletions

diff --git a/tests/codegen/asm-maybe-uninit.rs b/tests/codegen/asm-maybe-uninit.rs
new file mode 100644
index 00000000000..d7e4a948954
--- /dev/null
+++ b/tests/codegen/asm-maybe-uninit.rs
@@ -0,0 +1,27 @@
+// compile-flags: -O
+// only-x86_64
+
+#![crate_type = "rlib"]
+#![allow(asm_sub_register)]
+
+use std::mem::MaybeUninit;
+use std::arch::asm;
+
+// CHECK-LABEL: @int
+#[no_mangle]
+pub unsafe fn int(x: MaybeUninit<i32>) -> MaybeUninit<i32> {
+    let y: MaybeUninit<i32>;
+    asm!("/*{}{}*/", in(reg) x, out(reg) y);
+    y
+}
+
+// CHECK-LABEL: @inout
+#[no_mangle]
+pub unsafe fn inout(mut x: i32) -> MaybeUninit<u32> {
+    let mut y: MaybeUninit<u32>;
+    asm!("/*{}*/", inout(reg) x => y);
+    asm!("/*{}*/", inout(reg) y => x);
+    asm!("/*{}*/", inlateout(reg) x => y);
+    asm!("/*{}*/", inlateout(reg) y => x);
+    y
+}