> Optimize HandleAllocator for fast ID churning.
>
> Instead of calculating ranges of IDs and the overhead with updating
> them every allocation/release, store a released ID list in a small
> FastVector.
>
> Optimize the allocate path for the "good case" of no reserved IDs so
> that it either pops the last released ID or incriments a next value and
> returns it. Release has a similar cost of just a push_back when there
> are no reserved IDs.
>
> This adds a small fixed memory cost due to the FastVector and a dynamic
> memory cost of mReleasedList having up to N elements where N is the
> maxmimum total handles allocated at one time.
>
> Bug: angleproject:8434
> Change-Id: I7c5aa126b5303c105cd2464d0d0933b922cc2b8f
> Reviewed-on:
https://chromium-review.googlesource.com/c/angle/angle/+/5101509> Reviewed-by: Charlie Lao <
cc...@google.com>
> Commit-Queue: Shahbaz Youssefi <
syou...@chromium.org>