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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 01:47:29 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-19 01:47:29 +0000
commit0ebf5bdf043a27fd3dfb7f92e0cb63d88954c44d (patch)
treea31f07c9bcca9d56ce61e9a1ffd30ef350d513aa /third_party/rust/bytes/benches/buf.rs
parentInitial commit. (diff)
downloadfirefox-esr-0ebf5bdf043a27fd3dfb7f92e0cb63d88954c44d.tar.xz
firefox-esr-0ebf5bdf043a27fd3dfb7f92e0cb63d88954c44d.zip
Adding upstream version 115.8.0esr.upstream/115.8.0esr
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'third_party/rust/bytes/benches/buf.rs')
-rw-r--r--third_party/rust/bytes/benches/buf.rs186
1 files changed, 186 insertions, 0 deletions
diff --git a/third_party/rust/bytes/benches/buf.rs b/third_party/rust/bytes/benches/buf.rs
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+++ b/third_party/rust/bytes/benches/buf.rs
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+#![feature(test)]
+#![warn(rust_2018_idioms)]
+
+extern crate test;
+
+use bytes::Buf;
+use test::Bencher;
+
+/// Dummy Buf implementation
+struct TestBuf {
+ buf: &'static [u8],
+ readlens: &'static [usize],
+ init_pos: usize,
+ pos: usize,
+ readlen_pos: usize,
+ readlen: usize,
+}
+impl TestBuf {
+ fn new(buf: &'static [u8], readlens: &'static [usize], init_pos: usize) -> TestBuf {
+ let mut buf = TestBuf {
+ buf,
+ readlens,
+ init_pos,
+ pos: 0,
+ readlen_pos: 0,
+ readlen: 0,
+ };
+ buf.reset();
+ buf
+ }
+ fn reset(&mut self) {
+ self.pos = self.init_pos;
+ self.readlen_pos = 0;
+ self.next_readlen();
+ }
+ /// Compute the length of the next read :
+ /// - use the next value specified in readlens (capped by remaining) if any
+ /// - else the remaining
+ fn next_readlen(&mut self) {
+ self.readlen = self.buf.len() - self.pos;
+ if let Some(readlen) = self.readlens.get(self.readlen_pos) {
+ self.readlen = std::cmp::min(self.readlen, *readlen);
+ self.readlen_pos += 1;
+ }
+ }
+}
+impl Buf for TestBuf {
+ fn remaining(&self) -> usize {
+ self.buf.len() - self.pos
+ }
+ fn advance(&mut self, cnt: usize) {
+ self.pos += cnt;
+ assert!(self.pos <= self.buf.len());
+ self.next_readlen();
+ }
+ fn chunk(&self) -> &[u8] {
+ if self.readlen == 0 {
+ Default::default()
+ } else {
+ &self.buf[self.pos..self.pos + self.readlen]
+ }
+ }
+}
+
+/// Dummy Buf implementation
+/// version with methods forced to not be inlined (to simulate costly calls)
+struct TestBufC {
+ inner: TestBuf,
+}
+impl TestBufC {
+ fn new(buf: &'static [u8], readlens: &'static [usize], init_pos: usize) -> TestBufC {
+ TestBufC {
+ inner: TestBuf::new(buf, readlens, init_pos),
+ }
+ }
+ fn reset(&mut self) {
+ self.inner.reset()
+ }
+}
+impl Buf for TestBufC {
+ #[inline(never)]
+ fn remaining(&self) -> usize {
+ self.inner.remaining()
+ }
+ #[inline(never)]
+ fn advance(&mut self, cnt: usize) {
+ self.inner.advance(cnt)
+ }
+ #[inline(never)]
+ fn chunk(&self) -> &[u8] {
+ self.inner.chunk()
+ }
+}
+
+macro_rules! bench {
+ ($fname:ident, testbuf $testbuf:ident $readlens:expr, $method:ident $(,$arg:expr)*) => (
+ #[bench]
+ fn $fname(b: &mut Bencher) {
+ let mut bufs = [
+ $testbuf::new(&[1u8; 8+0], $readlens, 0),
+ $testbuf::new(&[1u8; 8+1], $readlens, 1),
+ $testbuf::new(&[1u8; 8+2], $readlens, 2),
+ $testbuf::new(&[1u8; 8+3], $readlens, 3),
+ $testbuf::new(&[1u8; 8+4], $readlens, 4),
+ $testbuf::new(&[1u8; 8+5], $readlens, 5),
+ $testbuf::new(&[1u8; 8+6], $readlens, 6),
+ $testbuf::new(&[1u8; 8+7], $readlens, 7),
+ ];
+ b.iter(|| {
+ for i in 0..8 {
+ bufs[i].reset();
+ let buf: &mut dyn Buf = &mut bufs[i]; // type erasure
+ test::black_box(buf.$method($($arg,)*));
+ }
+ })
+ }
+ );
+ ($fname:ident, slice, $method:ident $(,$arg:expr)*) => (
+ #[bench]
+ fn $fname(b: &mut Bencher) {
+ // buf must be long enough for one read of 8 bytes starting at pos 7
+ let arr = [1u8; 8+7];
+ b.iter(|| {
+ for i in 0..8 {
+ let mut buf = &arr[i..];
+ let buf = &mut buf as &mut dyn Buf; // type erasure
+ test::black_box(buf.$method($($arg,)*));
+ }
+ })
+ }
+ );
+ ($fname:ident, option) => (
+ #[bench]
+ fn $fname(b: &mut Bencher) {
+ let data = [1u8; 1];
+ b.iter(|| {
+ for _ in 0..8 {
+ let mut buf = Some(data);
+ let buf = &mut buf as &mut dyn Buf; // type erasure
+ test::black_box(buf.get_u8());
+ }
+ })
+ }
+ );
+}
+
+macro_rules! bench_group {
+ ($method:ident $(,$arg:expr)*) => (
+ bench!(slice, slice, $method $(,$arg)*);
+ bench!(tbuf_1, testbuf TestBuf &[], $method $(,$arg)*);
+ bench!(tbuf_1_costly, testbuf TestBufC &[], $method $(,$arg)*);
+ bench!(tbuf_2, testbuf TestBuf &[1], $method $(,$arg)*);
+ bench!(tbuf_2_costly, testbuf TestBufC &[1], $method $(,$arg)*);
+ // bench!(tbuf_onebyone, testbuf TestBuf &[1,1,1,1,1,1,1,1], $method $(,$arg)*);
+ // bench!(tbuf_onebyone_costly, testbuf TestBufC &[1,1,1,1,1,1,1,1], $method $(,$arg)*);
+ );
+}
+
+mod get_u8 {
+ use super::*;
+ bench_group!(get_u8);
+}
+mod get_u16 {
+ use super::*;
+ bench_group!(get_u16);
+}
+mod get_u32 {
+ use super::*;
+ bench_group!(get_u32);
+}
+mod get_u64 {
+ use super::*;
+ bench_group!(get_u64);
+}
+mod get_f32 {
+ use super::*;
+ bench_group!(get_f32);
+}
+mod get_f64 {
+ use super::*;
+ bench_group!(get_f64);
+}
+mod get_uint24 {
+ use super::*;
+ bench_group!(get_uint, 3);
+}