Convert arrays of Int32 to arrays of Int for integer arithmetic

[ksluder (Kyle Sluder)]

Quoting @scanon from your previous thread:

@scanon

The vDSP library is about 30 years old (and its direct predecessors were a decade or two older than that); optimizing compilers were not always as good as they are today. If someone were writing a vDSP-like library from scratch today, they might not include some of these operations (or they might--a function call is still a little bit tidier than a for loop, depending on your taste).

If you’re just doing 4 native-integer additions, you probably don’t need to use vDSP. CPUs have already figured out how to issue multiple integer operations without requiring code to be rewritten.

But you will want to use overflow-disabled operators to ensure optimal codegen:

@scanon

@ksluder

The Swift version is doing overflow checking.

Not for Double. Overflow produces infinity per IEEE-754 rules, no checks required.

(However, for integer arithmetic, you'd absolutely want to do that to unlock vectorization)