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|
// run-pass
#![feature(test)]
extern crate test;
use std::mem::size_of;
use test::black_box;
// Ensure the const-eval result and runtime result of float comparison are equivalent.
macro_rules! compare {
($op:tt) => {
compare!(
[f64::NEG_INFINITY, -f64::MAX, -1.0, -0.0, 0.0, 1.0, f64::MAX, f64::INFINITY, f64::NAN],
$op
);
};
([$($lhs:expr),+], $op:tt) => {
$(compare!(
$lhs,
$op,
[f64::NEG_INFINITY, -f64::MAX, -1.0, -0.0, 0.0, 1.0, f64::MAX, f64::INFINITY, f64::NAN]
);)+
};
($lhs:expr, $op:tt, [$($rhs:expr),+]) => {
$({
// Wrap the check in its own function to reduce time needed to borrowck.
fn check() {
static CONST_EVAL: bool = $lhs $op $rhs;
let runtime_eval = black_box($lhs) $op black_box($rhs);
assert_eq!(CONST_EVAL, runtime_eval, stringify!($lhs $op $rhs));
assert_eq!(
size_of::<[u8; ($lhs $op $rhs) as usize]>(),
runtime_eval as usize,
stringify!($lhs $op $rhs (forced const eval))
);
}
check();
})+
};
}
fn main() {
assert_eq!(0.0/0.0 < 0.0/0.0, false);
assert_eq!(0.0/0.0 > 0.0/0.0, false);
assert_eq!(f64::NAN < f64::NAN, false);
assert_eq!(f64::NAN > f64::NAN, false);
compare!(==);
compare!(!=);
compare!(<);
compare!(<=);
compare!(>);
compare!(>=);
}
|
