tree 2da57684f426a4c79a6a6c51a307482266876fd9
parent 2385e126d14e376cc71ce7a5ff5a721072886fac
author Bartek Nowierski <bartekn@chromium.org> 1645445873 +0000
committer Chromium LUCI CQ <chromium-scoped@luci-project-accounts.iam.gserviceaccount.com> 1645445873 +0000

[PA] Implement dynamically sized GigaCage (disabled)

This allows supporting the following scenarios (none of each is enabled
in this CL):

1. Lower the GigaCage size on 64-bit Windows <8.1, due to
   ERROR_COMMITMENT_LIMIT crashes. (See crbug.com/1217759)

2. Increase the GigaCage size on newer Windows where Courgette needs it,
   without increasing it on earlier versions. (See crbug.com/1286318)

3. Lower the GigaCage size on iOS for test runner, which can't get
   "Extended Virtual Addressing" entitlement. (Needed to tackle
   crbug.com/1250788)

Enabling dynamically sized GigaCage converts some constexpr to
variables. Not ideal, but we expect the perf impact to be negligible,
since the variables are placed in their own, write-once cacheline,
which we expect to be hot. This benchmarks suggests that there should be
no performance difference
https://quick-bench.com/q/I6aiDNT2zgLkU8h6ZXLNtDaTfVA

Change-Id: I28a077df6434f68cbcb2d3811ed0dc30d4782dce
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/3274408
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Reviewed-by: Anton Bikineev <bikineev@chromium.org>
Reviewed-by: Benoit Lize <lizeb@chromium.org>
Commit-Queue: Bartek Nowierski <bartekn@chromium.org>
Cr-Commit-Position: refs/heads/main@{#973489}