Hi! I’ve opened a bug report (#54344) on github today which was immediately closed and I was sent here. I’ve read that for a good performance @code_warntype macro should produce an output without lines colored in red. For this purpose I should write code which is “type stable” and there is no “type …

What is the output of versioninfo()? I am unable to reproduce. julia> @code_warntype foo(Array{Bool,3}(undef, 1, 2, 3), x -> sum(2x), [2]) MethodInstance for foo(::Array{Bool, 3}, ::var"#4#5", ::Vector{Int64}) from foo(array, op, xs) @ Main REPL[5]:1 Arguments #self#::Core.Const(foo) array::A…

Sorry, @mkitti , I’ve completely forgotten about this! julia> versioninfo() Julia Version 1.10.3 Commit 0b4590a550 (2024-04-30 10:59 UTC) Build Info: Official https://julialang.org/ release Platform Info: OS: FreeBSD (x86_64-unknown-freebsd13.2) CPU: 16 × AMD Ryzen 7 5800X 8-Core Processor W…

This might be a particular instance of when Julia tries to avoid specializing. See https://docs.julialang.org/en/v1/manual/performance-tips/#Be-aware-of-when-Julia-avoids-specializing

I don’t know the reason, but in case someone can explain it to those who are not as knowledgeable: If instead of using broadcasting, you use the map function, @code_warntype returns the expected output. I hope I’m not making a silly comparison; I know that using map is not always equivalent to a br…

Yes, it seems like a problem in broadcasting. I would like to use broadcasting in my particular case :frowning: @mkitti I don’t know if the link you provided explains why this example works with map.

[image] shamazmazum: What a penalty for this may be? In general, Any is like Object in Java. It designates a variable that could potentially hold any value, so results in boxing. [image] shamazmazum: How does your type inference work? Julias type inference is, due to being a semantica…

The question may be asked in another way: how costly is it to work with boxed objects? What can be done in this case to avoid type instability?

[image] shamazmazum: how costly is it to work with boxed objects? That’ll depend on what exactly you’re doing :person_shrugging: For cases where you’re basically doing just numerical work and you’d expect SIMD to occur, it’s catastrophic. Boxing with Any loses type information, so there’s no …

My real-life function computes three-point correlation for an array in a set of points like this: function autocorr3_point(array :: AbstractArray{<:Number, N}, shift2 :: NTuple{N, Int}, shift3 :: NTuple{N, Int}) where N rot1 = array rot2 =…

Why Julia fails to infere types in this example? What is the cost of this? What are requirements for type inference?

General Usage

shamazmazum May 3, 2024, 4:25pm 4

Exactly, if I execute it, @code_warntype works as expected. Isn’t it weird?

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Why Julia fails to infere types in this example? What is the cost of this? What are requirements for type inference?

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