Add benchmarks for impl Debug for str
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| assert_eq!(s.len(), 64); | ||
| assert_eq!(w.buf, expected); | ||
| assert_eq!(w.write_calls, expected_write_calls); |
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Generally it's better to separate tests from benchmarks. That makes it easier to rewrite the benchmarks in case the optimizer gets too clever and optimizes things away. And it measures fewer things which should increase the SNR.
Right now this would also be benchmarking string comparison.
I know we have a few benchmarks which mix things, but they're not a good example to follow.
You can still write them in a single #[bench] function by running the asserts outside the benchmark loop.
Or you can declare the test strings as consts so they can be reused between tests and benches.
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You can still write them in a single #[bench] function by running the asserts outside the benchmark loop.
Or you can declare the test strings as consts so they can be reused between tests and benches.
I first tried to extract those to the tests directory, but then ended up leaving them together inside the #[bench] fn outside of the benchmark loop as you suggested.
IMO it makes sense to co-locate these, as especially counting / optimizing the write calls is done purely for performance reasons.
In order to inform future perf improvements and prevent regressions, lets add some benchmarks that stress `impl Debug for str`.
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Works for me! @bors r+ rollup |
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Add benchmarks for `impl Debug for str` In order to inform future perf improvements and prevent regressions, lets add some benchmarks that stress `impl Debug for str`. --- As I am currently working on improving the perf in rust-lang#121150, its nice to have these benchmarks. Writing them, I also saw that escapes are written out one char at a time, even though other parts of the code are already optimizing that via `as_str`, which I intend to do as well as a followup improvement. r? `@cuviper` ☝🏻 as you were also assigned to rust-lang#121150, CC `@the8472` if you want to steal the review :-)
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…iaskrgr Rollup of 7 pull requests Successful merges: - rust-lang#124551 (Add benchmarks for `impl Debug for str`) - rust-lang#124914 (Remove `#[macro_use] extern crate rustc middle` from numerous crates) - rust-lang#124915 (`rustc_target` cleanups) - rust-lang#124918 (Eliminate some `FIXME(lcnr)` comments) - rust-lang#124927 (opt-dist: use xz2 instead of xz crate) - rust-lang#124936 (analyse visitor: build proof tree in probe) - rust-lang#124943 (always use `GenericArgsRef`) Failed merges: - rust-lang#124955 (Use fewer origins when creating type variables.) r? `@ghost` `@rustbot` modify labels: rollup
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…iaskrgr Rollup of 7 pull requests Successful merges: - rust-lang#124551 (Add benchmarks for `impl Debug for str`) - rust-lang#124915 (`rustc_target` cleanups) - rust-lang#124918 (Eliminate some `FIXME(lcnr)` comments) - rust-lang#124927 (opt-dist: use xz2 instead of xz crate) - rust-lang#124936 (analyse visitor: build proof tree in probe) - rust-lang#124943 (always use `GenericArgsRef`) - rust-lang#124955 (Use fewer origins when creating type variables.) r? `@ghost` `@rustbot` modify labels: rollup
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Rollup merge of rust-lang#124551 - Swatinem:debug-str-bench, r=cuviper Add benchmarks for `impl Debug for str` In order to inform future perf improvements and prevent regressions, lets add some benchmarks that stress `impl Debug for str`. --- As I am currently working on improving the perf in rust-lang#121150, its nice to have these benchmarks. Writing them, I also saw that escapes are written out one char at a time, even though other parts of the code are already optimizing that via `as_str`, which I intend to do as well as a followup improvement. r? ``@cuviper`` ☝🏻 as you were also assigned to rust-lang#121150, CC ``@the8472`` if you want to steal the review :-)
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…iaskrgr Rollup of 7 pull requests Successful merges: - rust-lang#124551 (Add benchmarks for `impl Debug for str`) - rust-lang#124915 (`rustc_target` cleanups) - rust-lang#124918 (Eliminate some `FIXME(lcnr)` comments) - rust-lang#124927 (opt-dist: use xz2 instead of xz crate) - rust-lang#124936 (analyse visitor: build proof tree in probe) - rust-lang#124943 (always use `GenericArgsRef`) - rust-lang#124955 (Use fewer origins when creating type variables.) r? `@ghost` `@rustbot` modify labels: rollup
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In order to inform future perf improvements and prevent regressions, lets add some benchmarks that stress
impl Debug for str.As I am currently working on improving the perf in #121150, its nice to have these benchmarks.
Writing them, I also saw that escapes are written out one char at a time, even though other parts of the code are already optimizing that via
as_str, which I intend to do as well as a followup improvement.r? @cuviper
☝🏻 as you were also assigned to #121150, CC @the8472 if you want to steal the review :-)