rust/tests/codegen/lib-optimizations/slice_rotate.rs
2025-02-11 13:41:35 -08:00

30 lines
847 B
Rust

//@ compile-flags: -Copt-level=3
#![crate_type = "lib"]
// Ensure that the simple case of rotating by a constant 1 optimizes to the obvious thing
// CHECK-LABEL: @rotate_left_by_one
#[no_mangle]
pub fn rotate_left_by_one(slice: &mut [i32]) {
// CHECK-NOT: phi
// CHECK-NOT: call
// CHECK-NOT: load
// CHECK-NOT: store
// CHECK-NOT: getelementptr
// CHECK: %[[END:.+]] = getelementptr
// CHECK-NEXT: %[[DIM:.+]] = getelementptr
// CHECK-NEXT: %[[LAST:.+]] = load
// CHECK-NEXT: %[[FIRST:.+]] = shl
// CHECK-NEXT: call void @llvm.memmove
// CHECK-NEXT: store i32 %[[LAST]], ptr %[[DIM:.+]]
// CHECK-NOT: phi
// CHECK-NOT: call
// CHECK-NOT: load
// CHECK-NOT: store
// CHECK-NOT: getelementptr
// CHECK: ret void
if !slice.is_empty() {
slice.rotate_left(1);
}
}