Original commit message:
Also, CodeGenerator::MakeCodeEpilogue now accepts an optional pointer
to a EhFrameWriter and will attach unwinding information to the code
object when passed one.
Reason for reverting:
The STATIC_CONST_MEMBER_DEFINITION in eh-frame-writer-unittest.cc
causes a compiler error on V8 Win64 - clang buildbot.
Removing that bit.
BUG=v8:4899
LOG=N
Review-Url: https://codereview.chromium.org/2023503002
Cr-Commit-Position: refs/heads/master@{#37754}
Original commit message:
Also, CodeGenerator::MakeCodeEpilogue now accepts an optional pointer
to a EhFrameWriter and will attach unwinding information to the code
object when passed one.
Reason for reverting:
The STATIC_CONST_MEMBER_DEFINITION in eh-frame-writer-unittest.cc
causes a compiler error on V8 Win64 - clang buildbot.
Removing that bit.
BUG=v8:4899
LOG=N
Review-Url: https://codereview.chromium.org/2023503002
Cr-Commit-Position: refs/heads/master@{#37707}
Reason for revert:
The STATIC_CONST_MEMBER_DEFINITION in eh-frame-writer-unittest.cc causes a compiler error on V8 Win64 - clang buildbot. Removing that bit should be sufficient.
Original issue's description:
> Implement .eh_frame writer and disassembler.
>
> Also, CodeGenerator::MakeCodeEpilogue now accepts an optional pointer
> to a EhFrameWriter and will attach unwinding information to the code
> object when passed one.
>
> BUG=v8:4899
> LOG=N
>
> Committed: https://crrev.com/27d810e63b744b5b3d9aa28ff21413247773e6c2
> Cr-Commit-Position: refs/heads/master@{#37683}
TBR=rmcilroy@chromium.org,jarin@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true
BUG=v8:4899
Review-Url: https://codereview.chromium.org/2143033002
Cr-Commit-Position: refs/heads/master@{#37688}
Also, CodeGenerator::MakeCodeEpilogue now accepts an optional pointer
to a EhFrameWriter and will attach unwinding information to the code
object when passed one.
BUG=v8:4899
LOG=N
Review-Url: https://codereview.chromium.org/2023503002
Cr-Commit-Position: refs/heads/master@{#37683}
the .eh_frame format as part of the jitdump generated when
FLAG_perf_prof is enabled. The final goal is allowing precise unwinding
of callchains that include JITted code when profiling V8 using perf.
Unwinding information is stored in the body of code objects after the
code itself, prefixed with its length and aligned to a 8-byte boundary.
A boolean flag in the header signals its presence, resulting in zero
memory overhead when the generation of unwinding info is disabled or
no such information was attached to the code object.
A new jitdump record type (with id 4) is introduced for specifying
optional unwinding information for code load records. The EhFrameHdr
struct is also introduced, together with a constructor to initialise it
from the associated code object.
At this stage no unwinding information is written to the jitdump, but
the infrastructure for doing so is ready in place.
BUG=v8:4899
LOG=N
Review-Url: https://codereview.chromium.org/1993653003
Cr-Commit-Position: refs/heads/master@{#37296}
