Improve the dealloc and realloc functions to more agressively reuse memory #35
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| @@ -834,7 +834,19 @@ unsafe impl<'a> alloc::Alloc for &'a Bump { | |||
| } | |||
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| #[inline(always)] | |||
| unsafe fn dealloc(&mut self, _ptr: NonNull<u8>, _layout: Layout) {} | |||
| unsafe fn dealloc(&mut self, ptr: NonNull<u8>, layout: Layout) { | |||
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Can you replace the #[inline(always)] to just #[inline] now that this isn't a no-op? Thanks.
src/lib.rs
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| if footer_usize.checked_sub(old_size) == Some(ptr.as_ptr() as usize) { | ||
| // Our strategy is to deallocate the old allocation and then do a new | ||
| // allocation of the required size hoping for it to fit in the same | ||
| // location. |
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I'd prefer to keep the old strategy of trying to allocate the delta in place in this chunk.
Relying on the fact that we currently never touch any of the bytes we de-allocate is a little too subtle for my tastes, and it cuts off introducing poison patterns or other things like that in the future. This is also a bit more code than the original, and it isn't clear to me that it has any perf benefit, is better at reusing memory, or anything like that.
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That makes a lot of sense. I have pushed a new version which still passes the same test as before. Could you take a look and see if you find it acceptable?
…er to reason about
I found a final issue while looking over the code again.