• Jakob Gruber's avatar
    Reland "[osr] Use the new OSR cache" · 91453880
    Jakob Gruber authored
    This is a reland of commit 91da3883
    
    Fixed: Use an X register for JumpIfCodeTIsMarkedForDeoptimization
    on arm64.
    
    Original change's description:
    > [osr] Use the new OSR cache
    >
    > This CL switches over our OSR system to be based on the feedback
    > vector osr caches.
    >
    > - OSRing to Sparkplug is fully separated from OSR urgency. If
    >   SP code exists, we simply jump to it, no need to maintain an
    >   installation request.
    > - Each JumpLoop checks its dedicated FeedbackVector cache slot.
    >   If a valid target code object exists, we enter it *without*
    >   calling into runtime to fetch the code object.
    > - Finally, OSR urgency still remains as the heuristic for
    >   requesting Turbofan OSR compile jobs. Note it no longer has a
    >   double purpose of being a generic untargeted installation
    >   request.
    >
    > With the new system in place, we can remove now-unnecessary
    > hacks:
    >
    > - Early OSR tierup is replaced by the standard OSR system. Any
    >   present OSR code is automatically entered.
    > - The synchronous OSR compilation fallback is removed. With
    >   precise installation (= per-JumpLoop-bytecode) we no longer
    >   have the problem of 'getting unlucky' with JumpLoop/cache entry
    >   mismatches. Execution has moved on while compiling? Simply spawn
    >   a new concurrent compile job.
    > - Remove the synchronous (non-OSR) Turbofan compile request now
    >   that we always enter available OSR code as early as possible.
    > - Tiering into Sparkplug no longer messes with OSR state.
    >
    > Bug: v8:12161
    > Change-Id: I0a85e53d363504b7dac174dbaf69c03c35e66700
    > Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3596167
    > Commit-Queue: Jakob Linke <jgruber@chromium.org>
    > Auto-Submit: Jakob Linke <jgruber@chromium.org>
    > Reviewed-by: Leszek Swirski <leszeks@chromium.org>
    > Commit-Queue: Leszek Swirski <leszeks@chromium.org>
    > Cr-Commit-Position: refs/heads/main@{#80147}
    
    Bug: v8:12161
    Change-Id: Ib3597cf1d99cdb5d0f2c5ac18e311914f376231d
    Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3606232
    Auto-Submit: Jakob Linke <jgruber@chromium.org>
    Reviewed-by: 's avatarLeszek Swirski <leszeks@chromium.org>
    Commit-Queue: Leszek Swirski <leszeks@chromium.org>
    Cr-Commit-Position: refs/heads/main@{#80167}
    91453880
code.h 47.1 KB