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| author | Albert Larsan <74931857+albertlarsan68@users.noreply.github.com> | 2023-01-05 09:13:28 +0100 |
|---|---|---|
| committer | Albert Larsan <74931857+albertlarsan68@users.noreply.github.com> | 2023-01-11 09:32:08 +0000 |
| commit | cf2dff2b1e3fa55fa5415d524200070d0d7aacfe (patch) | |
| tree | 40a88d9a46aaf3e8870676eb2538378b75a263eb /tests/codegen/dst-vtable-align-nonzero.rs | |
| parent | ca855e6e42787ecd062d81d53336fe6788ef51a9 (diff) | |
| download | rust-cf2dff2b1e3fa55fa5415d524200070d0d7aacfe.tar.gz rust-cf2dff2b1e3fa55fa5415d524200070d0d7aacfe.zip | |
Move /src/test to /tests
Diffstat (limited to 'tests/codegen/dst-vtable-align-nonzero.rs')
| -rw-r--r-- | tests/codegen/dst-vtable-align-nonzero.rs | 61 |
1 files changed, 61 insertions, 0 deletions
diff --git a/tests/codegen/dst-vtable-align-nonzero.rs b/tests/codegen/dst-vtable-align-nonzero.rs new file mode 100644 index 00000000000..54f6e7f992f --- /dev/null +++ b/tests/codegen/dst-vtable-align-nonzero.rs @@ -0,0 +1,61 @@ +// compile-flags: -O -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<T: ?Sized> { x: u8, y: T } + +pub struct WrapperWithAlign2<T: ?Sized> { x: u16, y: T } + +pub struct Struct<W: ?Sized> { + _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<dyn Trait>> +) -> &WrapperWithAlign1<dyn Trait> { + // 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<dyn Trait>> +) -> &WrapperWithAlign2<dyn Trait> { + // 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} |
