Due to immutable loads being placed earlier during scheduling and
subsequently being spilled, the safepoint table of a function may grow
significantly. Until we implement an optimization to avoid spilling in
such cases, we disable immutable loads for tagged values.

Bug: chromium:1191540, v8:11510
Change-Id: Ia5c5d274e6d4b9145cd028828f9a328a65bed17f
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2796953
Commit-Queue: Manos Koukoutos <manoskouk@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#73743}