//@ compile-flags: -O //@ only-64bit (because we're using [ui]size) #![crate_type = "lib"] #![feature(slice_from_ptr_range)] // This is intentionally using a non-power-of-two array length, // as that's where the optimization differences show up // CHECK-LABEL: @flatten_via_ptr_range #[no_mangle] pub fn flatten_via_ptr_range(slice_of_arrays: &[[i32; 13]]) -> &[i32] { // CHECK-NOT: lshr // CHECK-NOT: udiv // CHECK: mul nuw nsw i64 %{{.+}}, 13 // CHECK-NOT: lshr // CHECK-NOT: udiv let r = slice_of_arrays.as_ptr_range(); let r = r.start.cast()..r.end.cast(); unsafe { core::slice::from_ptr_range(r) } }