Add a push_light method and use likely/unlikely intrinsics#134
Add a push_light method and use likely/unlikely intrinsics#134Zoxc wants to merge 1 commit intoservo:masterfrom
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| #[cfg(not(feature = "push_light"))] | ||
| fn push_light(&mut self, _: T) {} |
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I don't understand why this is defined if the feature is missing, and why it does nothing.
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It's to ensure things still compile
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It compiles sure, but it doesn't do the right thing, why should it be a noop if the feature is missing? Sounds like a way to have silent bugs.
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It's not meaningful to benchmark a feature if it's disabled
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Oh ok sorry I didn't notice this was an implementation for benchmarks.
| trait Vector<T>: for<'a> From<&'a [T]> + Extend<T> + ExtendFromSlice<T> { | ||
| fn new() -> Self; | ||
| fn push(&mut self, val: T); | ||
| fn push_light(&mut self, val: T); |
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IMO this should either not exist when the feature is not enabled, or delegate to push in the default implementation.
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So the speedup when the vector isn't spilled is more than 2x (both with and without inlining, I added benchmarks to test it without the |
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It probably does make sense to make it the default behavior. |
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Additionally, I would mark this function |
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☔ The latest upstream changes (presumably #169) made this pull request unmergeable. Please resolve the merge conflicts. |
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Was this ever made the default behaviour? It seems like an easy win. |
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We can't make this the default as written, because even without the |
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I pushed a rebased version of this PR plus a commit to make At a glance, it looks like this is still a win for |
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You can always have a |
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Yes, the branch I linked above keeps the unstable intrinsics behind an optional feature. |
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This adds a
push_lightalternative topushwhich is optimized for inlining and for vectors which fit inside the fixed size.This change is