• Jakob Gruber's avatar
    [nci] Update interrupt budget from NCI code · 980e224a
    Jakob Gruber authored
    This is the first step towards implementing a tier-up mechanism from
    NCI code to TF. We will follow the existing Ignition-to-Turbofan
    mechanics, which are, roughly:
    
    1. Track a bytecode interrupt budget.
    2. When exhausted, call the runtime profiler, which increments
       profiler ticks for the top frame's function.
    3. When a function should tier up, it is marked as such using the
       FeedbackVector::optimized_code_weak_or_smi slot / the
       OptimizationMarker mechanism.
    4. The InterpreterEntryTrampoline checks this slot and calls into
       runtime to compile if needed.
    5. The finished code is also placed into this slot, as well as
       installed on the JSFunction.
    6. Again, the IET checks the slot and tail-calls the code object if it
       exists.
    
    This CL implements step 1 for NCI code by inserting the new simplified
    UpdateInterruptBudget operator at the same spots (and using the same
    offsets) as Ignition. When the budget is exhausted, we call a runtime
    function that currently does nothing and will be implemented in the
    next CL.
    
    Bug: v8:8888
    Change-Id: I98c0f8d96f32d515218dc2a76f961d44fe281c86
    Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2312778
    Commit-Queue: Jakob Gruber <jgruber@chromium.org>
    Reviewed-by: 's avatarGeorg Neis <neis@chromium.org>
    Reviewed-by: 's avatarMythri Alle <mythria@chromium.org>
    Cr-Commit-Position: refs/heads/master@{#69124}
    980e224a
access-builder.cc 43.6 KB