rust/tests/codegen/slice-iter-len-eq-zero.rs

29 lines
830 B
Rust

// no-system-llvm
// compile-flags: -O
// ignore-debug: the debug assertions add extra comparisons
#![crate_type = "lib"]
type Demo = [u8; 3];
// CHECK-LABEL: @slice_iter_len_eq_zero
#[no_mangle]
pub fn slice_iter_len_eq_zero(y: std::slice::Iter<'_, Demo>) -> bool {
// CHECK-NOT: sub
// CHECK: %[[RET:.+]] = icmp eq {{i8\*|ptr}} {{%1|%0}}, {{%1|%0}}
// CHECK: ret i1 %[[RET]]
y.len() == 0
}
// CHECK-LABEL: @array_into_iter_len_eq_zero
#[no_mangle]
pub fn array_into_iter_len_eq_zero(y: std::array::IntoIter<Demo, 123>) -> bool {
// This should be able to just check that the indexes are equal, and not
// need any subtractions or comparisons to handle `start > end`.
// CHECK-NOT: icmp
// CHECK-NOT: sub
// CHECK: %_0 = icmp eq {{i16|i32|i64}}
// CHECK: ret i1 %_0
y.len() == 0
}