Joseph Richey 53daa3c593
Use REP MOVSB/STOSB when the ERMSB feature is present (#392)
* Reorganize mem functions

This reduces the amount of platform-specific code

Signed-off-by: Joe Richey <joerichey@google.com>

* Use ERMSB implementations if the feature is set

Signed-off-by: Joe Richey <joerichey@google.com>

* Add non-aligned benchmarks

Signed-off-by: Joe Richey <joerichey@google.com>
2020-11-03 08:57:08 -06:00

195 lines
4.5 KiB
Rust

#![feature(test)]
extern crate test;
use test::{black_box, Bencher};
extern crate compiler_builtins;
use compiler_builtins::mem::{memcmp, memcpy, memmove, memset};
fn memcpy_builtin(b: &mut Bencher, n: usize, offset: usize) {
let v1 = vec![1u8; n + offset];
let mut v2 = vec![0u8; n + offset];
b.bytes = n as u64;
b.iter(|| {
let src: &[u8] = black_box(&v1[offset..]);
let dst: &mut [u8] = black_box(&mut v2[offset..]);
dst.copy_from_slice(src);
})
}
fn memcpy_rust(b: &mut Bencher, n: usize, offset: usize) {
let v1 = vec![1u8; n + offset];
let mut v2 = vec![0u8; n + offset];
b.bytes = n as u64;
b.iter(|| {
let src: &[u8] = black_box(&v1[offset..]);
let dst: &mut [u8] = black_box(&mut v2[offset..]);
unsafe { memcpy(dst.as_mut_ptr(), src.as_ptr(), n) }
})
}
fn memset_builtin(b: &mut Bencher, n: usize, offset: usize) {
let mut v1 = vec![0u8; n + offset];
b.bytes = n as u64;
b.iter(|| {
let dst: &mut [u8] = black_box(&mut v1[offset..]);
let val: u8 = black_box(27);
for b in dst {
*b = val;
}
})
}
fn memset_rust(b: &mut Bencher, n: usize, offset: usize) {
let mut v1 = vec![0u8; n + offset];
b.bytes = n as u64;
b.iter(|| {
let dst: &mut [u8] = black_box(&mut v1[offset..]);
let val = black_box(27);
unsafe { memset(dst.as_mut_ptr(), val, n) }
})
}
fn memcmp_builtin(b: &mut Bencher, n: usize) {
let v1 = vec![0u8; n];
let mut v2 = vec![0u8; n];
v2[n - 1] = 1;
b.bytes = n as u64;
b.iter(|| {
let s1: &[u8] = black_box(&v1);
let s2: &[u8] = black_box(&v2);
s1.cmp(s2)
})
}
fn memcmp_rust(b: &mut Bencher, n: usize) {
let v1 = vec![0u8; n];
let mut v2 = vec![0u8; n];
v2[n - 1] = 1;
b.bytes = n as u64;
b.iter(|| {
let s1: &[u8] = black_box(&v1);
let s2: &[u8] = black_box(&v2);
unsafe { memcmp(s1.as_ptr(), s2.as_ptr(), n) }
})
}
fn memmove_builtin(b: &mut Bencher, n: usize) {
let mut v = vec![0u8; n + n / 2];
b.bytes = n as u64;
b.iter(|| {
let s: &mut [u8] = black_box(&mut v);
s.copy_within(0..n, n / 2);
})
}
fn memmove_rust(b: &mut Bencher, n: usize) {
let mut v = vec![0u8; n + n / 2];
b.bytes = n as u64;
b.iter(|| {
let dst: *mut u8 = black_box(&mut v[n / 2..]).as_mut_ptr();
let src: *const u8 = black_box(&v).as_ptr();
unsafe { memmove(dst, src, n) };
})
}
#[bench]
fn memcpy_builtin_4096(b: &mut Bencher) {
memcpy_builtin(b, 4096, 0)
}
#[bench]
fn memcpy_rust_4096(b: &mut Bencher) {
memcpy_rust(b, 4096, 0)
}
#[bench]
fn memcpy_builtin_1048576(b: &mut Bencher) {
memcpy_builtin(b, 1048576, 0)
}
#[bench]
fn memcpy_rust_1048576(b: &mut Bencher) {
memcpy_rust(b, 1048576, 0)
}
#[bench]
fn memcpy_builtin_4096_offset(b: &mut Bencher) {
memcpy_builtin(b, 4096, 65)
}
#[bench]
fn memcpy_rust_4096_offset(b: &mut Bencher) {
memcpy_rust(b, 4096, 65)
}
#[bench]
fn memcpy_builtin_1048576_offset(b: &mut Bencher) {
memcpy_builtin(b, 1048576, 65)
}
#[bench]
fn memcpy_rust_1048576_offset(b: &mut Bencher) {
memcpy_rust(b, 1048576, 65)
}
#[bench]
fn memset_builtin_4096(b: &mut Bencher) {
memset_builtin(b, 4096, 0)
}
#[bench]
fn memset_rust_4096(b: &mut Bencher) {
memset_rust(b, 4096, 0)
}
#[bench]
fn memset_builtin_1048576(b: &mut Bencher) {
memset_builtin(b, 1048576, 0)
}
#[bench]
fn memset_rust_1048576(b: &mut Bencher) {
memset_rust(b, 1048576, 0)
}
#[bench]
fn memset_builtin_4096_offset(b: &mut Bencher) {
memset_builtin(b, 4096, 65)
}
#[bench]
fn memset_rust_4096_offset(b: &mut Bencher) {
memset_rust(b, 4096, 65)
}
#[bench]
fn memset_builtin_1048576_offset(b: &mut Bencher) {
memset_builtin(b, 1048576, 65)
}
#[bench]
fn memset_rust_1048576_offset(b: &mut Bencher) {
memset_rust(b, 1048576, 65)
}
#[bench]
fn memcmp_builtin_4096(b: &mut Bencher) {
memcmp_builtin(b, 4096)
}
#[bench]
fn memcmp_rust_4096(b: &mut Bencher) {
memcmp_rust(b, 4096)
}
#[bench]
fn memcmp_builtin_1048576(b: &mut Bencher) {
memcmp_builtin(b, 1048576)
}
#[bench]
fn memcmp_rust_1048576(b: &mut Bencher) {
memcmp_rust(b, 1048576)
}
#[bench]
fn memmove_builtin_4096(b: &mut Bencher) {
memmove_builtin(b, 4096)
}
#[bench]
fn memmove_rust_4096(b: &mut Bencher) {
memmove_rust(b, 4096)
}
#[bench]
fn memmove_builtin_1048576(b: &mut Bencher) {
memmove_builtin(b, 1048576)
}
#[bench]
fn memmove_rust_1048576(b: &mut Bencher) {
memmove_rust(b, 1048576)
}