eliminate turing machines from more array functions

Author: vtjnash

base/abstractarray.jl

@@ -1668,15 +1668,15 @@ end
 function _sub2ind!(Iout, inds, Iinds, I)
     @_noinline_meta
     for i in Iinds
-        # Iout[i] = sub2ind(inds, map(Ij->Ij[i], I)...)
+        # Iout[i] = sub2ind(inds, map(Ij -> Ij[i], I)...)
         Iout[i] = sub2ind_vec(inds, i, I)
     end
     Iout
 end
 
-sub2ind_vec(inds, i, I) = (@_inline_meta; _sub2ind_vec(inds, (), i, I...))
-_sub2ind_vec(inds, out, i, I1, I...) = (@_inline_meta; _sub2ind_vec(inds, (out..., I1[i]), i, I...))
-_sub2ind_vec(inds, out, i) = (@_inline_meta; sub2ind(inds, out...))
+sub2ind_vec(inds, i, I) = (@_inline_meta; sub2ind(inds, _sub2ind_vec(i, I...)...))
+_sub2ind_vec(i, I1, I...) = (@_inline_meta; (I1[i], _sub2ind_vec(i, I...)...))
+_sub2ind_vec(i) = ()
 
 function ind2sub(inds::Union{DimsInteger{N},Indices{N}}, ind::AbstractVector{<:Integer}) where N
     M = length(ind)

base/permuteddimsarray.jl

@@ -74,10 +74,7 @@ end
     val
 end
 
-# For some reason this is faster than ntuple(d->I[perm[d]], Val{N}) (#15276?)
-@inline genperm(I::NTuple{N,Any}, perm::Dims{N}) where {N} = _genperm((), I, perm...)
-_genperm(out, I) = out
-@inline _genperm(out, I, p, perm...) = _genperm((out..., I[p]), I, perm...)
+@inline genperm(I::NTuple{N,Any}, perm::Dims{N}) where {N} = ntuple(d -> I[perm[d]], Val{N})
 @inline genperm(I, perm::AbstractVector{Int}) = genperm(I, (perm...,))
 
 """

base/reshapedarray.jl

@@ -167,11 +167,11 @@ parentindexes(A::ReshapedArray) = map(s->1:s, size(parent(A)))
 reinterpret(::Type{T}, A::ReshapedArray, dims::Dims) where {T} = reinterpret(T, parent(A), dims)
 
 @inline ind2sub_rs(::Tuple{}, i::Int) = i
-@inline ind2sub_rs(strds, i) = ind2sub_rs((), strds, i-1)
-@inline ind2sub_rs(out, ::Tuple{}, ind) = (ind+1, out...)
-@inline function ind2sub_rs(out, strds, ind)
+@inline ind2sub_rs(strds, i) = _ind2sub_rs(strds, i - 1)
+@inline _ind2sub_rs(::Tuple{}, ind) = (ind + 1,)
+@inline function _ind2sub_rs(strds, ind)
     d, r = divrem(ind, strds[1])
-    ind2sub_rs((d+1, out...), tail(strds), r)
+    (_ind2sub_rs(tail(strds), r)..., d + 1)
 end
 
 @inline function getindex(A::ReshapedArrayLF, index::Int)