... in order to improve quality of C++ assembly.

This CL also switches C++ code to use branchful decompression.

Bug: v8:9353
Change-Id: Id6a5cc5db2ad729b4394cd541a7ec8035c0d4571
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1677204
Commit-Queue: Igor Sheludko <ishell@chromium.org>
Reviewed-by: Leszek Swirski <leszeks@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62372}