Is there a way to guarantee 0 allocations when accessing an array?

ChrisRackauckas · May 18, 2017, 12:58am

This is the PR to follow:

github.com/JuliaLang/julia

GC support for stack allocated objects

JuliaLang:jn/codegen_rewrite ← JuliaLang:ob/stknew

opened 06:56PM - 18 Jul 15 UTC

carnaval

+84017 -49754

Only works with copy_stacks for now. The code is not used anywhere in codegen ri…ght now, it can be tested by using (:stknew typ args...) instead of :new. It is essentially the GC side of #8134 but without the global alloca stack & unmarking, so @JeffBezanson will probably be happier. Stack objects are kept marked (+young) permanently and are only scanned when coming from the owning task. Note that this is on top of jn/codegen_rewrite under the "no codegen change policy" :-) cc @vtjnash

github.com/JuliaLang/julia

Want non-allocating array views

opened 12:03PM - 06 Feb 16 UTC

closed 02:28PM - 03 May 20 UTC

timholy

performance

I couldn't find an open issue for this frequently-noted problem, so I'm filing t…his. Feel free to close if there's an earlier one. It's worth linking to https://groups.google.com/forum/#!topic/julia-users/6Z1kJ5LrSMU, where it was pointed out that "faking" a view as `(A, R)`, where `R` is a `CartesianRange`, is currently the cleanest way to circumvent this problem (but can only handle the equivalent of `Int/UnitRange/Colon` indexes). Various solutions using `Ptr` have also been employed in the past, but of course those suffer from the standpoint of garbage-collection safety.

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Is there a way to guarantee 0 allocations when accessing an array?

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