When freezing flags, not only remember this in a global variable, but
also actually memory-protect the memory that holds the flag values.
R=cbruni@chromium.org
CC=sroettger@chromium.org
Bug: v8:12887
Cq-Include-Trybots: luci.v8.try:v8_linux_blink_rel
Change-Id: I2ae638790d1f08f4bcc1b7e6cb5970e4e7463aad
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3811286
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/main@{#82478}
After flags are frozen, this will not work any more. It's also not
required, as flags cannot be accessed after teardown anyway.
This CL changes that to only release the memory of dynamically allocated
string flags, which is something we still need to do after
write-protecting the flags anyway.
R=tebbi@chromium.org
Bug: v8:12887
Change-Id: Iff0e3845cbd91fb59878b2ed36a44d6df00572f4
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3695379
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Cr-Commit-Position: refs/heads/main@{#81030}
Extend the effect of --freeze-flags-after-init to also protect updates
of individual flags instead of only the API.
For this, we wrap each flag in a {FlagValue} class which implicitly
converts to the value of the flag. Some cases still require the explicit
{value()} accessor though. That accessor is {constexpr}, in contrast to
the implicit conversion, because otherwise clang emits a lot of warnings
about dead code within "if (FLAG...)" scopes.
R=cbruni@chromium.org
Bug: v8:12887
Change-Id: I87d3457e49ceb317d34d6a21cf09c520d4171eb5
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3683321
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Reviewed-by: Jakob Kummerow <jkummerow@chromium.org>
Reviewed-by: Patrick Thier <pthier@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Reviewed-by: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80938}
Use the existing {base::Optional} instead of the extra {MaybeBoolFlag}
struct. This makes writing to a maybe-flag simpler because you just
write a boolean value and that automatically initializes the optional.
R=cbruni@chromium.org
Bug: v8:12887
Change-Id: I940d20286d65ba4355dc04b4b6068a306706f295
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3686412
Reviewed-by: Camillo Bruni <cbruni@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/main@{#80915}
