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//@ compile-flags: -Copt-level=3
//@ needs-deterministic-layouts (opposite scalar pair orders breaks it)
#![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 ptr {{%y.0, %y.1|%y.1, %y.0}}
// CHECK: ret i1 %[[RET]]
y.len() == 0
}
// CHECK-LABEL: @slice_iter_len_eq_zero_ref
#[no_mangle]
pub fn slice_iter_len_eq_zero_ref(y: &mut std::slice::Iter<'_, Demo>) -> bool {
// CHECK-NOT: sub
// CHECK: %[[A:.+]] = load ptr
// CHECK-SAME: !nonnull
// CHECK: %[[B:.+]] = load ptr
// CHECK-SAME: !nonnull
// CHECK: %[[RET:.+]] = icmp eq ptr %[[A]], %[[B]]
// CHECK: ret i1 %[[RET]]
y.len() == 0
}
struct MyZST;
// CHECK-LABEL: @slice_zst_iter_len_eq_zero
#[no_mangle]
pub fn slice_zst_iter_len_eq_zero(y: std::slice::Iter<'_, MyZST>) -> bool {
// CHECK: %[[RET:.+]] = icmp eq ptr %y.1, null
// CHECK: ret i1 %[[RET]]
y.len() == 0
}
// CHECK-LABEL: @slice_zst_iter_len_eq_zero_ref
#[no_mangle]
pub fn slice_zst_iter_len_eq_zero_ref(y: &mut std::slice::Iter<'_, MyZST>) -> bool {
// CHECK: %[[LEN:.+]] = load ptr
// CHECK-NOT: !nonnull
// CHECK: %[[RET:.+]] = icmp eq ptr %[[LEN]], null
// 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
}
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