FailedChanges

Summary

  1. [profile] Clean up stale raw profiles in instrprof-write-file.c (details)
  2. [profile] Add a mode to continuously sync counter updates to a file (details)
Commit ade776b5845384bb45fcd2f7919d80f4101971a7 by Vedant Kumar
[profile] Clean up stale raw profiles in instrprof-write-file.c
The file was modifiedcompiler-rt/test/profile/instrprof-write-file.c
Commit d889d1efefe9f97507e3eafa85a2e3939df9750f by Vedant Kumar
[profile] Add a mode to continuously sync counter updates to a file
Add support for continuously syncing profile counter updates to a file.
The motivation for this is that programs do not always exit cleanly. On
iOS, for example, programs are usually killed via a signal from the OS.
Running atexit() handlers after catching a signal is unreliable, so some
method for progressively writing out profile data is necessary.
The approach taken here is to mmap() the `__llvm_prf_cnts` section onto
a raw profile. To do this, the linker must page-align the counter and
data sections, and the runtime must ensure that counters are mapped to a
page-aligned offset within a raw profile.
Continuous mode is (for the moment) incompatible with the online merging
mode. This limitation is lifted in https://reviews.llvm.org/D69586.
Continuous mode is also (for the moment) incompatible with value
profiling, as I'm not sure whether there is interest in this and the
implementation may be tricky.
As I have not been able to test extensively on non-Darwin platforms,
only Darwin support is included for the moment. However, continuous mode
may "just work" without modification on Linux and some UNIX-likes. AIUI
the default value for the GNU linker's `--section-alignment` flag is set
to the page size on many systems. This appears to be true for LLD as
well, as its `no_nmagic` option is on by default. Continuous mode will
not "just work" on Fuchsia or Windows, as it's not possible to mmap() a
section on these platforms. There is a proposal to add a layer of
indirection to the profile instrumentation to support these platforms.
rdar://54210980
Differential Revision: https://reviews.llvm.org/D68351
The file was addedcompiler-rt/test/profile/ContinuousSyncMode/lit.local.cfg.py
The file was modifiedcompiler-rt/lib/profile/InstrProfData.inc
The file was modifiedllvm/include/llvm/ProfileData/InstrProfData.inc
The file was modifiedllvm/test/tools/llvm-profdata/raw-32-bits-le.test
The file was modifiedclang/docs/SourceBasedCodeCoverage.rst
The file was addedcompiler-rt/test/profile/ContinuousSyncMode/multiple-DSOs.c
The file was modifiedcompiler-rt/lib/profile/InstrProfilingWriter.c
The file was modifiedllvm/test/tools/llvm-profdata/Inputs/c-general.profraw
The file was addedcompiler-rt/test/profile/ContinuousSyncMode/set-file-object.c
The file was modifiedllvm/lib/ProfileData/InstrProfReader.cpp
The file was modifiedllvm/test/tools/llvm-profdata/c-general.test
The file was modifiedllvm/test/tools/llvm-profdata/raw-32-bits-be.test
The file was modifiedllvm/test/tools/llvm-profdata/raw-64-bits-be.test
The file was modifiedllvm/test/tools/llvm-profdata/raw-64-bits-le.test
The file was modifiedllvm/test/tools/llvm-profdata/raw-two-profiles.test
The file was addedcompiler-rt/test/profile/ContinuousSyncMode/set-filename.c
The file was addedcompiler-rt/test/profile/ContinuousSyncMode/darwin-proof-of-concept.c
The file was modifiedcompiler-rt/lib/profile/InstrProfilingBuffer.c
The file was addedcompiler-rt/test/profile/ContinuousSyncMode/basic.c
The file was addedcompiler-rt/test/profile/ContinuousSyncMode/pid-substitution.c
The file was modifiedclang/test/Driver/darwin-ld.c
The file was modifiedcompiler-rt/lib/profile/InstrProfilingRuntime.cpp
The file was modifiedcompiler-rt/lib/profile/InstrProfilingPort.h
The file was modifiedllvm/test/tools/llvm-profdata/malformed-ptr-to-counter-array.test
The file was modifiedcompiler-rt/lib/profile/InstrProfiling.h
The file was modifiedcompiler-rt/lib/profile/InstrProfilingFile.c
The file was modifiedclang/lib/Driver/ToolChains/Darwin.cpp