Force specialization on mutable operate

[blegat]

@kalmarek Can you confirm that it fixes your issue ?

[codecov]

Codecov Report

Merging #116 (57b2f6c) into master (3f455a4) will not change coverage.
The diff coverage is 100.00%.

@@           Coverage Diff           @@
##           master     #116   +/-   ##
=======================================
  Coverage   85.29%   85.29%           
=======================================
  Files          18       18           
  Lines        1673     1673           
=======================================
  Hits         1427     1427           
  Misses        246      246           

Impacted Files	Coverage Δ
src/interface.jl	93.96% <100.00%> (ø)

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[kalmarek]

not really:

activate --temp
add MutableArithmetics#bl/mutable_op_F
add JuMP, Random, LinearAlgebra

using LinearAlgebra, JuMP, Random
let dims = [31, 24, 49, 30, 33, 49, 33, 21, 44, 50, 50, 32, 31, 48, 28, 34, 35, 41, 25, 43]
    model = Model()
    Ps = [
        JuMP.@variable(model, [1:d, 1:d])
        for d in dims
    ]
    Ms = [rand(d,d) for d in dims]
    
    @time JuMP.@constraint(model, sum(dot(P, M) for (P,M) in zip(Ps, Ms)) == 1.0 )
    @time JuMP.@constraint(model, sum(dot(Ps[i], Ms[i]) for i in eachindex(dims)) == 1.0 )
    
    model
end;

gives (after warmup)

0.007942 seconds (208.41 k allocations: 9.852 MiB)
0.009449 seconds (208.33 k allocations: 9.849 MiB)

[blegat]

Comparing to the timings of #111, it looks like the timings of JuMP v0.20

[kalmarek]

Indeed time spent is as of JuMP v20 ;) allocations are not altered by this change though

(jl_1XzHFh) pkg> st
      Status `/tmp/jl_1XzHFh/Project.toml`
  [4076af6c] JuMP v0.21.10
  [d8a4904e] MutableArithmetics v0.2.21 `https://github.com/jump-dev/MutableArithmetics.jl.git#bl/mutable_op_F`
  [37e2e46d] LinearAlgebra
  [9a3f8284] Random

EDIT: well actually the number of allocations has doubled, but not necessarily because of this change ;)

[blegat]

As mentioned in #111 (comment), I don't know what's happening with allocations :/