bug#42147: 28.0.50; pure vs side-effect-free, missing optimizations?

[Stefan Monnier]

>> Better yet, there's still hope that we change things such that `eq`
>> behaves like `eql` on bignums (and maybe also on floats).
> Speaking of which, Andrea may be in a good position to provide us with
> performance data about such a change, since making 'eq' more expensive is
> likely to be more visible in native code (assuming the operation is
> open-coded) than in bytecode or interpreted lisp. On the other hand, perhaps
> his compiler thingamajig is able to eliminate some checks statically by
> type propagation?

Note that it can also be done without slowing down `eq` (by
hash-consing the bignums).


        Stefan