2 stable releases
Uses old Rust 2015
1.0.1 | Feb 26, 2017 |
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#907 in Concurrency
3KB
This provides a consume ordering for when the compiler cannot elide the dependency
Examples
extern crate consume;
use std::sync::atomic::{AtomicPtr, AtomicUsize};
fn consume_load(pt: &AtomicPtr<*const usize>) -> usize {
// There's a data dependency on the loaded value,
// meaning that the compiler can't od silly things to
// eliminate the dependency
unsafe { *pt.load(Consume) }
}
fn incorrect_consume_load(ind: &AtomicUsize, vals: &Vec<usize>) -> usize {
// There is no data dependency here
// since the compiler can eliminate the loaded value
// from the pointer index. Ensure that you don't have this.
// Use consume at your own risk.
let i = ind.load(consume::Consume);
vals[ind - ind]
// vals[ind] would probably be correct, unless some shenanigans with the
// bounds checking occured. I only use vec for convenience, only
// use consume if you understand all possible data paths taken by the compiler
}