Eliminating dynamic dispatch performance bottleneck

[goerch]

Adding specializations to Base.getproperty and Base.setproperty to eliminate dynamic dispatch on Julia 1.7.0-rc1

[krynju]

Will wait on resolution/RCA on this JuliaLang/julia#42754 before merging.
This doesn't look like type piracy to me since all of this is passed through a method defined for an Union{Node,Nothing} type, but maybe this can get addressed directly in julia instead

[goerch]

Only method mentioned was Base.setproperty!(::Nothing) and we could live with or without it probably. But waiting on the resolution seems reasonable too.

[krynju]

Yeah, but you don't define such a method here, the _setproperty is a method only accessible through the union definition, so it won't replace the default

Unless I'm overlooking something this looks good to me

[goerch]

Edit: DataStructures.jl uses

@test [] == detect_ambiguities(Base, Core, DataStructures)

to detect type piracy.

[krynju]

@goerch JuliaLang/julia#42754 was merged, I guess that is included in the nightly build already

It doesn't really affect the benchmarks included in this repo (but I'm not sure whether they're 100% correct)

Let me know if it helps with your benchmarks and whether we still need this merged

[goerch]

Let me know if it helps with your benchmarks and whether we still need this merged

1.6.3 and 1.8.0-DEV now only show marginal improvements, 1.7.0-rc2 is still awaiting the patch. I committed a simplified version of the needed specialization.

[krynju]

Ok, so what you're saying is that this specialization still yields some noticeable improvements on both 1.6 and master?
Is there any difference in code generated with and without it?