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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 12:02:58 +0000
commit698f8c2f01ea549d77d7dc3338a12e04c11057b9 (patch)
tree173a775858bd501c378080a10dca74132f05bc50 /library/core/benches/num/int_log/mod.rs
parentInitial commit. (diff)
downloadrustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.tar.xz
rustc-698f8c2f01ea549d77d7dc3338a12e04c11057b9.zip
Adding upstream version 1.64.0+dfsg1.upstream/1.64.0+dfsg1
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'library/core/benches/num/int_log/mod.rs')
-rw-r--r--library/core/benches/num/int_log/mod.rs58
1 files changed, 58 insertions, 0 deletions
diff --git a/library/core/benches/num/int_log/mod.rs b/library/core/benches/num/int_log/mod.rs
new file mode 100644
index 000000000..19864d2d4
--- /dev/null
+++ b/library/core/benches/num/int_log/mod.rs
@@ -0,0 +1,58 @@
+use rand::Rng;
+use test::{black_box, Bencher};
+
+macro_rules! int_log_bench {
+ ($t:ty, $predictable:ident, $random:ident, $random_small:ident) => {
+ #[bench]
+ fn $predictable(bench: &mut Bencher) {
+ bench.iter(|| {
+ for n in 0..(<$t>::BITS / 8) {
+ for i in 1..=(100 as $t) {
+ let x = black_box(i << (n * 8));
+ black_box(x.log10());
+ }
+ }
+ });
+ }
+
+ #[bench]
+ fn $random(bench: &mut Bencher) {
+ let mut rng = crate::bench_rng();
+ /* Exponentially distributed random numbers from the whole range of the type. */
+ let numbers: Vec<$t> = (0..256)
+ .map(|_| {
+ let x = rng.gen::<$t>() >> rng.gen_range(0, <$t>::BITS);
+ if x != 0 { x } else { 1 }
+ })
+ .collect();
+ bench.iter(|| {
+ for x in &numbers {
+ black_box(black_box(x).log10());
+ }
+ });
+ }
+
+ #[bench]
+ fn $random_small(bench: &mut Bencher) {
+ let mut rng = crate::bench_rng();
+ /* Exponentially distributed random numbers from the range 0..256. */
+ let numbers: Vec<$t> = (0..256)
+ .map(|_| {
+ let x = (rng.gen::<u8>() >> rng.gen_range(0, u8::BITS)) as $t;
+ if x != 0 { x } else { 1 }
+ })
+ .collect();
+ bench.iter(|| {
+ for x in &numbers {
+ black_box(black_box(x).log10());
+ }
+ });
+ }
+ };
+}
+
+int_log_bench! {u8, u8_log10_predictable, u8_log10_random, u8_log10_random_small}
+int_log_bench! {u16, u16_log10_predictable, u16_log10_random, u16_log10_random_small}
+int_log_bench! {u32, u32_log10_predictable, u32_log10_random, u32_log10_random_small}
+int_log_bench! {u64, u64_log10_predictable, u64_log10_random, u64_log10_random_small}
+int_log_bench! {u128, u128_log10_predictable, u128_log10_random, u128_log10_random_small}