• machenbach's avatar
    Revert of [profiler] Fix attribution for the top-most interpreted frame.... · 63dea876
    machenbach authored
    Revert of [profiler] Fix attribution for the top-most interpreted frame. (patchset #3 id:40001 of https://codereview.chromium.org/2667253004/ )
    
    Reason for revert:
    Flaky crashes on mac asan:
    https://build.chromium.org/p/client.v8/builders/V8%20Mac64%20ASAN/builds/10739
    
    Original issue's description:
    > [profiler] Fix attribution for the top-most interpreted frame.
    >
    > Before this change, we attributed samples for the top-most interpreter frame to the second-topmost frame if we were in a bytecode handler with elided frame. With this change we try to detect that we are in a handler without a frame. If we are, we do not drop the topmost frame.
    >
    > For example, consider the program
    >
    > function inner() {
    >   var s = 0;
    >   for (var i = 0; i < 100000; i++) {
    >     s += i * i;
    >   }
    >   return s;
    > }
    >
    > function trivial() {
    >   return inner();
    > }
    >
    > for (var i = 0; i < 2000; i++) {
    >   trivial();
    > }
    >
    >
    > Before this change, d8 --prof --ignition --nocrankshaft and linux-tick-processor would produce:
    >
    >   [JavaScript]:
    >    ticks  total  nonlib   name
    >    4885   83.4%   83.5%  Function: ~trivial a.js:15:17
    >     759   13.0%   13.0%  Function: ~inner a.js:7:15
    >
    > After this change, we get
    >
    >  [JavaScript]:
    >    ticks  total  nonlib   name
    >    5486   95.9%   96.2%  Function: ~inner a.js:7:15
    >       4    0.1%    0.1%  Function: ~trivial a.js:15:17
    >
    > Review-Url: https://codereview.chromium.org/2667253004
    > Cr-Commit-Position: refs/heads/master@{#42894}
    > Committed: https://chromium.googlesource.com/v8/v8/+/d07f6540c1f9628ed2ba1fa6507c90db07ccc5f5
    
    TBR=bmeurer@chromium.org,jarin@chromium.org
    # Skipping CQ checks because original CL landed less than 1 days ago.
    NOPRESUBMIT=true
    NOTREECHECKS=true
    NOTRY=true
    
    Review-Url: https://codereview.chromium.org/2670843005
    Cr-Commit-Position: refs/heads/master@{#42912}
    63dea876
frames.cc 76.3 KB