For variable proxies in a function inside an eval scope that point to
a dynamic variable in the eval scope, the current scope resolution will
find this variable only when the function is eagerly compiled, as the
eval scope only exists during top-level eval compilation. This causes
a mismatch between lazy- and eager- compiled functions.
With this patch, we skip these dynamic variables during lookup, so that
the lookup for the variable proxy always finds a kDynamicLocal or
kDynamicGlobal, both when compiled lazily and eagerly. This is a minor
pessimisation of performance (as we know that the lookup has to be
dynamic), but unblocks other improvements which require idempotent
bytecode generation (such as lazy source positions).
Note that the alternative, of simply not tracking dynamic variables on
the eval scope at all, is not viable due to needing this information
during conflict detection.
Bug: v8:8510
Bug: v8:9511
Change-Id: Ifa72ec05e9a97b7be418912340081b9656765fd4
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1733077
Commit-Queue: Leszek Swirski <leszeks@chromium.org>
Reviewed-by: Dan Elphick <delphick@chromium.org>
Reviewed-by: Toon Verwaest <verwaest@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63051}
