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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
commit698f8c2f01ea549d77d7dc3338a12e04c11057b9 (patch)
tree173a775858bd501c378080a10dca74132f05bc50 /src/test/codegen/dst-vtable-align-nonzero.rs
parentInitial commit. (diff)
downloadrustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.tar.xz
rustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.zip
Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/test/codegen/dst-vtable-align-nonzero.rs')
-rw-r--r--src/test/codegen/dst-vtable-align-nonzero.rs45
1 files changed, 45 insertions, 0 deletions
diff --git a/src/test/codegen/dst-vtable-align-nonzero.rs b/src/test/codegen/dst-vtable-align-nonzero.rs
new file mode 100644
index 000000000..14c4c3f30
--- /dev/null
+++ b/src/test/codegen/dst-vtable-align-nonzero.rs
@@ -0,0 +1,45 @@
+// compile-flags: -O
+
+#![crate_type = "lib"]
+
+// 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: [[RANGE_META]] = !{[[USIZE]] 1, [[USIZE]] 0}