- Lower LoadObjectField to LoadFromObject
- Mark LoadFromObject and StoreToObject as non-allocating
- Use optimizable BitcastTaggedSignedToWord in TaggedIsNotSmi check

R=jarin@chromium.org, tebbi@chromium.org

Change-Id: I42992d46597be795aee3702018f7efd93fcc6ebf
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1657926
Commit-Queue: Georg Schmid <gsps@google.com>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/master@{#62173}