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Neutron3529 3ad4d24751
Optimize the code to run faster. 
such code is copy from
https://github.com/rust-lang/rust/blob/master/library/std/src/f32.rs
and
https://github.com/rust-lang/rust/blob/master/library/std/src/f64.rs
using r+rhs.abs() is faster than calc it directly.
Bench result:
```
$ cargo bench
   Compiling div-euclid v0.1.0 (/me/div-euclid)
    Finished bench [optimized] target(s) in 1.01s
     Running unittests src/lib.rs (target/release/deps/div_euclid-7a4530ca7817d1ef)

running 7 tests
test tests::it_works ... ignored
test tests::bench_aaabs     ... bench:  10,498,793 ns/iter (+/- 104,360)
test tests::bench_aadefault ... bench:  11,061,862 ns/iter (+/- 94,107)
test tests::bench_abs       ... bench:  10,477,193 ns/iter (+/- 81,942)
test tests::bench_default   ... bench:  10,622,983 ns/iter (+/- 25,119)
test tests::bench_zzabs     ... bench:  10,481,971 ns/iter (+/- 43,787)
test tests::bench_zzdefault ... bench:  11,074,976 ns/iter (+/- 29,633)

test result: ok. 0 passed; 0 failed; 1 ignored; 6 measured; 0 filtered out; finished in 19.35s
```
bench code:
```
#![feature(test)]
extern crate test;

fn rem_euclid(a:i32,rhs:i32)->i32{
    let r = a % rhs;
    if r < 0 { r + rhs.abs() } else { r }
}

#[cfg(test)]
mod tests {
    use super::*;
    use test::Bencher;
    use rand::prelude::*;
    use rand::rngs::SmallRng;
    const N:i32=1000;
    #[test]
    fn it_works() {
        let a: i32 = 7; // or any other integer type
        let b = 4;

        let d:Vec<i32>=(-N..=N).collect();
        let n:Vec<i32>=(-N..0).chain(1..=N).collect();

        for i in &d {
            for j in &n {
                assert_eq!(i.rem_euclid(*j),rem_euclid(*i,*j));
            }
        }

        assert_eq!(rem_euclid(a,b), 3);
        assert_eq!(rem_euclid(-a,b), 1);
        assert_eq!(rem_euclid(a,-b), 3);
        assert_eq!(rem_euclid(-a,-b), 1);
    }


    #[bench]
    fn bench_aaabs(b: &mut Bencher) {
        let mut d:Vec<i32>=(-N..=N).collect();
        let mut n:Vec<i32>=(-N..0).chain(1..=N).collect();
        let mut rng=SmallRng::from_seed([1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,21]);
        n.shuffle(&mut rng);
        d.shuffle(&mut rng);
        n.shuffle(&mut rng);
        b.iter(||{
            let mut res=0;
            for i in &d {
                for j in &n {
                    res+=rem_euclid(*i,*j);
                }
            }
            res
        });
    }
    #[bench]
    fn bench_aadefault(b: &mut Bencher) {
        let mut d:Vec<i32>=(-N..=N).collect();
        let mut n:Vec<i32>=(-N..0).chain(1..=N).collect();
        let mut rng=SmallRng::from_seed([1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,21]);
        n.shuffle(&mut rng);
        d.shuffle(&mut rng);
        n.shuffle(&mut rng);
        b.iter(||{
            let mut res=0;
            for i in &d {
                for j in &n {
                    res+=i.rem_euclid(*j);
                }
            }
            res
        });
    }

    #[bench]
    fn bench_abs(b: &mut Bencher) {
        let d:Vec<i32>=(-N..=N).collect();
        let n:Vec<i32>=(-N..0).chain(1..=N).collect();
        b.iter(||{
            let mut res=0;
            for i in &d {
                for j in &n {
                    res+=rem_euclid(*i,*j);
                }
            }
            res
        });
    }
    #[bench]
    fn bench_default(b: &mut Bencher) {
        let d:Vec<i32>=(-N..=N).collect();
        let n:Vec<i32>=(-N..0).chain(1..=N).collect();
        b.iter(||{
            let mut res=0;
            for i in &d {
                for j in &n {
                    res+=i.rem_euclid(*j);
                }
            }
            res
        });
    }

    #[bench]
    fn bench_zzabs(b: &mut Bencher) {
        let mut d:Vec<i32>=(-N..=N).collect();
        let mut n:Vec<i32>=(-N..0).chain(1..=N).collect();
        let mut rng=SmallRng::from_seed([1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,21]);
        d.shuffle(&mut rng);
        n.shuffle(&mut rng);
        d.shuffle(&mut rng);
        b.iter(||{
            let mut res=0;
            for i in &d {
                for j in &n {
                    res+=rem_euclid(*i,*j);
                }
            }
            res
        });
    }
    #[bench]
    fn bench_zzdefault(b: &mut Bencher) {
        let mut d:Vec<i32>=(-N..=N).collect();
        let mut n:Vec<i32>=(-N..0).chain(1..=N).collect();
        let mut rng=SmallRng::from_seed([1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,31,21]);
        d.shuffle(&mut rng);
        n.shuffle(&mut rng);
        d.shuffle(&mut rng);
        b.iter(||{
            let mut res=0;
            for i in &d {
                for j in &n {
                    res+=i.rem_euclid(*j);
                }
            }
            res
        });
    }
}
```
2022-11-03 16:35:37 +08:00
..
alloc Rollup merge of #103807 - H4x5:string-extend-from-within-tracking-issue, r=Dylan-DPC 2022-11-02 22:32:04 +05:30
backtrace@07872f28cd Update backtrace 2022-09-02 16:09:58 -04:00
core Optimize the code to run faster. 2022-11-03 16:35:37 +08:00
panic_abort Update comment about personalities in panic_abort 2022-08-23 16:12:58 +08:00
panic_unwind Fix alloc size 2022-10-23 20:30:16 +01:00
portable-simd separate the receiver from arguments in HIR under /clippy 2022-09-05 22:25:57 +09:00
proc_macro Stabilize proc_macro::Span::source_text 2022-10-18 17:13:41 +02:00
profiler_builtins
rtstartup Remove custom frame info registration on i686-pc-windows-gnu 2022-08-23 16:12:58 +08:00
rustc-std-workspace-alloc
rustc-std-workspace-core
rustc-std-workspace-std
std Rollup merge of #103637 - ChrisDenton:stdio-uwp, r=thomcc 2022-11-01 20:00:38 -04:00
stdarch@790411f93c library: update stdarch submodule 2022-10-13 09:41:16 +08:00
test Include both benchmarks and tests in the numbers given to TeFiltered{,Out} 2022-10-31 00:42:10 -07:00
unwind unwind: don't build dependency when building for Miri 2022-08-15 12:54:12 -04:00