Re: Check lateral references within PHVs for memoize cache keys

On Mon, Dec 25, 2023 at 3:01 PM Richard Guo <guofenglinux@gmail.com> wrote:

> On Thu, Jul 13, 2023 at 3:12 PM Richard Guo <guofenglinux@gmail.com>
> wrote:
>
>> So I'm wondering if it'd be better that we move all this logic of
>> computing additional lateral references within PHVs to get_memoize_path,
>> where we can examine only PHVs that are evaluated at innerrel.  And
>> considering that these lateral refs are only used by Memoize, it seems
>> more sensible to compute them there.  But I'm a little worried that
>> doing this would make get_memoize_path too expensive.
>>
>> Please see v4 patch for this change.
>>
>
> I'd like to add that not checking PHVs for lateral references can lead
> to performance regressions with Memoize node.
>

The v4 patch does not apply any more.  I've rebased it on master.
Nothing else has changed.

Thanks
Richard