1 files changed, 57 insertions, 0 deletions
diff --git a/tests/codegen-llvm/tuple-layout-opt.rs b/tests/codegen-llvm/tuple-layout-opt.rs
new file mode 100644
index 00000000000..5b2f65e7aa7
--- /dev/null
+++ b/tests/codegen-llvm/tuple-layout-opt.rs
@@ -0,0 +1,57 @@
+// 32-bit systems will return 128bit values using a return area pointer.
+//@ revisions: bit32 bit64
+//@[bit32] only-32bit
+//@[bit64] only-64bit
+//@ compile-flags: -C no-prepopulate-passes -Copt-level=0
+
+// Test that tuples get optimized layout, in particular with a ZST in the last field (#63244)
+
+#![crate_type = "lib"]
+
+type ScalarZstLast = (u128, ());
+// bit32: define {{(dso_local )?}}void @test_ScalarZstLast({{.*}} sret([16 x i8]) {{.*}}, i128 %_1)
+// bit64: define {{(dso_local )?}}i128 @test_ScalarZstLast(i128 %_1)
+#[no_mangle]
+pub fn test_ScalarZstLast(_: ScalarZstLast) -> ScalarZstLast {
+    loop {}
+}
+
+type ScalarZstFirst = ((), u128);
+// bit32: define {{(dso_local )?}}void @test_ScalarZstFirst({{.*}} sret([16 x i8]) {{.*}}, i128 %_1)
+// bit64: define {{(dso_local )?}}i128 @test_ScalarZstFirst(i128 %_1)
+#[no_mangle]
+pub fn test_ScalarZstFirst(_: ScalarZstFirst) -> ScalarZstFirst {
+    loop {}
+}
+
+type ScalarPairZstLast = (u8, u128, ());
+// CHECK: define {{(dso_local )?}}void @test_ScalarPairZstLast(ptr sret({{[^,]*}})
+// CHECK-SAME: %_0, i128 %_1.0, i8 %_1.1)
+#[no_mangle]
+pub fn test_ScalarPairZstLast(_: ScalarPairZstLast) -> ScalarPairZstLast {
+    loop {}
+}
+
+type ScalarPairZstFirst = ((), u8, u128);
+// CHECK: define {{(dso_local )?}}void @test_ScalarPairZstFirst(ptr sret({{[^,]*}})
+// CHECK-SAME: %_0, i8 %_1.0, i128 %_1.1)
+#[no_mangle]
+pub fn test_ScalarPairZstFirst(_: ScalarPairZstFirst) -> ScalarPairZstFirst {
+    loop {}
+}
+
+type ScalarPairLotsOfZsts = ((), u8, (), u128, ());
+// CHECK: define {{(dso_local )?}}void @test_ScalarPairLotsOfZsts(ptr sret({{[^,]*}})
+// CHECK-SAME: %_0, i128 %_1.0, i8 %_1.1)
+#[no_mangle]
+pub fn test_ScalarPairLotsOfZsts(_: ScalarPairLotsOfZsts) -> ScalarPairLotsOfZsts {
+    loop {}
+}
+
+type ScalarPairLottaNesting = (((), ((), u8, (), u128, ())), ());
+// CHECK: define {{(dso_local )?}}void @test_ScalarPairLottaNesting(ptr sret({{[^,]*}})
+// CHECK-SAME: %_0, i128 %_1.0, i8 %_1.1)
+#[no_mangle]
+pub fn test_ScalarPairLottaNesting(_: ScalarPairLottaNesting) -> ScalarPairLottaNesting {
+    loop {}
+}