Missing dataids methods

[martinholters]

E.g.

julia> x = [1,2,3];

julia> Base.mightalias(x, Diagonal(x))
false

because

julia> Base.dataids(x)
(0x00007f108ac6bbd0,)

julia> Base.dataids(Diagonal(x))
(0xce028b6f0a997db2,)

We should either go through all AbstractArray subtypes and double-check whether the dataids fallback is the right thing to do or we could try to come up with a more elaborate, probably @generated fallback.

[mbauman]

Yup, definitely missing a few here:

julia> methods(Base.dataids)
# 10 methods for generic function "dataids":
[1] dataids(A::Array) in Base at abstractarray.jl:1167
[2] dataids(::AbstractRange) in Base at abstractarray.jl:1168
[3] dataids(A::SubArray) in Base at subarray.jl:74
[4] dataids(a::Base.ReinterpretArray) in Base at reinterpretarray.jl:39
[5] dataids(A::Base.ReshapedArray) in Base at reshapedarray.jl:185
[6] dataids(A::Union{LinearAlgebra.Adjoint, LinearAlgebra.Transpose}) in LinearAlgebra at /home/mbauman/julia-wip1/usr/share/julia/site/v0.7/LinearAlgebra/src/adjtrans.jl:50
[7] dataids(S::SparseArrays.SparseMatrixCSC) in SparseArrays at /home/mbauman/julia-wip1/usr/share/julia/site/v0.7/SparseArrays/src/sparsematrix.jl:266
[8] dataids(S::SparseArrays.SparseVector) in SparseArrays at /home/mbauman/julia-wip1/usr/share/julia/site/v0.7/SparseArrays/src/sparsevector.jl:97
[9] dataids(A::AbstractArray) in Base at abstractarray.jl:1166
[10] dataids(x) in Base at abstractarray.jl:1169

julia> subtypes(AbstractArray)
32-element Array{Any,1}:
 AbstractRange
 Base.LogicalIndex
 Base.ReinterpretArray
 Base.ReshapedArray
 BitArray
 CartesianIndices
 Core.Compiler.AbstractRange
 Core.Compiler.BitArray
 Core.Compiler.SubArray
 DenseArray
 IterativeEigensolvers.AtA_or_AAt
 IterativeEigensolvers.SVDAugmented
 LinearAlgebra.AbstractQ
 LinearAlgebra.AbstractTriangular
 LinearAlgebra.Adjoint
 LinearAlgebra.Bidiagonal
 LinearAlgebra.ConjArray
 LinearAlgebra.Diagonal
 LinearAlgebra.Hermitian
 LinearAlgebra.HessenbergQ
 LinearAlgebra.LQPackedQ
 LinearAlgebra.RowVector
 LinearAlgebra.SymTridiagonal
 LinearAlgebra.Symmetric
 LinearAlgebra.Transpose
 LinearAlgebra.Tridiagonal
 LinearIndices
 PermutedDimsArray
 SparseArrays.AbstractSparseArray
 SubArray
 SuiteSparse.CHOLMOD.FactorComponent
 Test.GenericArray

(Plus the subtypes of DenseArray).