Add 1-index specialization of checkbounds

This seems important for good codegen with LinearSlow indexing

Author: timholy

base/abstractarray.jl

@@ -203,6 +203,10 @@ function checkbounds(::Type{Bool}, A::AbstractArray, I::AbstractArray{Bool})
     @_inline_meta
     checkbounds_logical(A, I)
 end
+function checkbounds(::Type{Bool}, A::AbstractArray, i)
+    @_inline_meta
+    checkbounds_indices(indices(A), (i,))
+end
 
 # checkbounds_indices iteratively consumes elements of the
 # indices-tuple of an arrray and the indices-tuple supplied by the
@@ -249,6 +253,10 @@ function checkbounds(A::AbstractArray, I...)
     @_inline_meta
     checkbounds(Bool, A, I...) || throw_boundserror(A, I)
 end
+function checkbounds(A::AbstractArray, i)
+    @_inline_meta
+    checkbounds(Bool, A, i) || throw_boundserror(A, (i,))
+end
 checkbounds(A::AbstractArray) = checkbounds(A, 1) # 0-d case
 
 # See also specializations in multidimensional