Simplify by using assembler function.

Bug: v8:10701
Change-Id: I7d07a271369fcf8ad34652b6e94463b0468ee1c5
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2346282
Commit-Queue: Eva Herencsárová <evih@google.com>
Reviewed-by: Thibaud Michaud <thibaudm@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#69328}