[PATCH] lookup_tag speedup

[Devang Patel]

hmm.. I will look at lang_identifier approach. One immediate question
is - how to handle situations where we want to process all tags for
given binding level?

Meanwhile, my current patch is far better than what we have today.
And work is complete. Would it be possible for this patch to get in
while we continue to work on even better alternatives ?

thoughts?
-Devang

On Wednesday, April 9, 2003, at 07:35 PM, Zack Weinberg wrote:

> Devang Patel <dpatel@apple.com> writes:
>
>> This patch gives 10% or more compile time speed up for real life
>> projects I used to measure compile time. It adds use of hash table
>> for tags lookup.
>
> I was just meaning to respond to the draft patch you sent last week.
>
> I think use of a hash table per binding level is overkill.  All you
> need to do is add a field to struct lang_identifier (call it
> tag_value), create an IDENTIFIER_TAG_VALUE macro to get at it given
> an IDENTIFIER_NODE, and then manage it the same way that
> IDENTIFIER_LOCAL_VALUE is currently managed -- look at poplevel.
>
> This is essentially the approach that I took doing the same thing, but
> if you restrict yourself to this change you shouldn't run into the
> headaches that I did.  We will get the memory back when I do finish my
> symbol lookup patch, so don't worry about bloating lang_identifier.
>
> zw