Add various optimizations for the in place interpreter, such as condensing large runs of block/loop instructions, and avoiding reallocating the vector as much.
<rdar://problem/113358427>
Pull request: https://github.com/WebKit/WebKit/pull/16363
Committed 266826@main (6f23b5f4342c): <https://commits.webkit.org/266826@main> Reviewed commits have been landed. Closing PR #16363 and removing active labels.