From a27f3e3fd1e4d16160f8885b6b06665b5319f56c Mon Sep 17 00:00:00 2001 From: Guillaume Gomez Date: Mon, 21 Jul 2025 14:34:12 +0200 Subject: Rename `tests/codegen` into `tests/codegen-llvm` --- tests/codegen-llvm/dst-vtable-align-nonzero.rs | 67 ++++++++++++++++++++++++++ 1 file changed, 67 insertions(+) create mode 100644 tests/codegen-llvm/dst-vtable-align-nonzero.rs (limited to 'tests/codegen-llvm/dst-vtable-align-nonzero.rs') diff --git a/tests/codegen-llvm/dst-vtable-align-nonzero.rs b/tests/codegen-llvm/dst-vtable-align-nonzero.rs new file mode 100644 index 00000000000..1404bd64f50 --- /dev/null +++ b/tests/codegen-llvm/dst-vtable-align-nonzero.rs @@ -0,0 +1,67 @@ +//@ compile-flags: -Copt-level=3 -Z merge-functions=disabled + +#![crate_type = "lib"] +#![feature(core_intrinsics)] + +// This test checks that we annotate alignment loads from vtables with nonzero range metadata, +// and that this allows LLVM to eliminate redundant `align >= 1` checks. + +pub trait Trait { + fn f(&self); +} + +pub struct WrapperWithAlign1 { + x: u8, + y: T, +} + +pub struct WrapperWithAlign2 { + x: u16, + y: T, +} + +pub struct Struct { + _field: i8, + dst: W, +} + +// CHECK-LABEL: @eliminates_runtime_check_when_align_1 +#[no_mangle] +pub fn eliminates_runtime_check_when_align_1( + x: &Struct>, +) -> &WrapperWithAlign1 { + // CHECK: load [[USIZE:i[0-9]+]], {{.+}} !range [[RANGE_META:![0-9]+]] + // CHECK-NOT: llvm.umax + // CHECK-NOT: icmp + // CHECK-NOT: select + // CHECK: ret + &x.dst +} + +// CHECK-LABEL: @does_not_eliminate_runtime_check_when_align_2 +#[no_mangle] +pub fn does_not_eliminate_runtime_check_when_align_2( + x: &Struct>, +) -> &WrapperWithAlign2 { + // CHECK: [[X0:%[0-9]+]] = load [[USIZE]], {{.+}} !range [[RANGE_META]] + // CHECK: {{icmp|llvm.umax}} + // CHECK: ret + &x.dst +} + +// CHECK-LABEL: @align_load_from_align_of_val +#[no_mangle] +pub fn align_load_from_align_of_val(x: &dyn Trait) -> usize { + // CHECK: {{%[0-9]+}} = load [[USIZE]], {{.+}} !range [[RANGE_META]] + core::mem::align_of_val(x) +} + +// CHECK-LABEL: @align_load_from_vtable_align_intrinsic +#[no_mangle] +pub unsafe fn align_load_from_vtable_align_intrinsic(x: &dyn Trait) -> usize { + let (data, vtable): (*const (), *const ()) = core::mem::transmute(x); + // CHECK: {{%[0-9]+}} = load [[USIZE]], {{.+}} !range [[RANGE_META]] + core::intrinsics::vtable_align(vtable) +} + +// CHECK: [[RANGE_META]] = !{[[USIZE]] 1, [[USIZE]] 0} -- cgit 1.4.1-3-g733a5