• Maya Lekova's avatar
    Revert "[cpu-profiler] Fix stack iterability for fast C calls with no exit frame" · 2f530d5c
    Maya Lekova authored
    This reverts commit d5f4a33e.
    
    Reason for revert: Seems to cause a no snapshot build failure - https://ci.chromium.org/p/v8/builders/luci.v8.ci/V8%20Linux%20-%20nosnap%20-%20debug/21967
    
    Original change's description:
    > [cpu-profiler] Fix stack iterability for fast C calls with no exit frame
    > 
    > Before fast C calls, store the current FP and PC on the isolate. When
    > iterating frames in SafeStackFrameIterator, check if these fields are
    > set and start iterating at the calling frame's FP instead of the current
    > FP, which will be in C++ code. We need to do this because c_entry_fp is
    > not set on the Isolate for Fast-C-Calls because we don't build an exit
    > frame.
    > 
    > This change makes stack samples that occur within 'Fast-C-Calls'
    > iterable, meaning we can properly attribute ticks within the JS caller.
    > 
    > Fast-C-Calls can't call back into JS code, so we can only ever have one
    > such call on the stack at a time, allowing us to store the FP on the
    > isolate rather than the stack.
    > 
    > TBR=v8-mips-ports@googlegroups.com
    > 
    > Bug: v8:8464, v8:7202
    > Change-Id: I7bf39eba779dad34754d5759d741c421b362a406
    > Reviewed-on: https://chromium-review.googlesource.com/c/1340241
    > Commit-Queue: Peter Marshall <petermarshall@chromium.org>
    > Reviewed-by: Jakob Gruber <jgruber@chromium.org>
    > Reviewed-by: Martyn Capewell <martyn.capewell@arm.com>
    > Reviewed-by: Alexei Filippov <alph@chromium.org>
    > Cr-Commit-Position: refs/heads/master@{#57896}
    
    TBR=alph@chromium.org,jgruber@chromium.org,petermarshall@chromium.org,martyn.capewell@arm.com,v8-arm-ports@googlegroups.com,v8-mips-ports@googlegroups.com,ibogosavljevic@wavecomp.com
    
    Change-Id: I85f846e57b6fa845e7770c616435cebffdb2a245
    No-Presubmit: true
    No-Tree-Checks: true
    No-Try: true
    Bug: v8:8464, v8:7202
    Reviewed-on: https://chromium-review.googlesource.com/c/1352302Reviewed-by: 's avatarMaya Lekova <mslekova@chromium.org>
    Commit-Queue: Maya Lekova <mslekova@chromium.org>
    Cr-Commit-Position: refs/heads/master@{#57899}
    2f530d5c
external-reference.cc 35 KB