Commit Graph

5 Commits

Author SHA1 Message Date
Ellis Hoag 18ffb5dc25 [InstrProf] Prevent duplicate functions in correlated data
When using debug info for profile correlation, avoid adding duplicate
functions in the synthetic Data section.

Before this patch, n duplicate function entries in the Data section would
cause counter values to be a factor of n larger. I built instrumented
clang with and without debug info correlation and got these summaries.

```
# With Debug Info Correlate
$ llvm-profdata show default.profdata
Instrumentation level: IR  entry_first = 0
Total functions: 182530
Maximum function count: 52034
Maximum internal block count: 5763

# Without
$ llvm-profdata show default.profdata
Instrumentation level: IR  entry_first = 0
Total functions: 183212
Maximum function count: 52034
Maximum internal block count: 5766
```

The slight difference in counts seem to be mostly from FileSystem and
Map functions and the difference in the number of instrumented functions
seems to come from missing debug info like destructors without source.

Reviewed By: kyulee

Differential Revision: https://reviews.llvm.org/D116051
2021-12-28 14:20:59 -08:00
Ellis Hoag 65d7fd0239 [Try2][InstrProf] Add Correlator class to read debug info
Extend `llvm-profdata` to read in a `.proflite` file and also a debug info file to generate a normal `.profdata` profile. This reduces the binary size by 8.4% when building an instrumented Clang binary without value profiling (164 MB vs 179 MB).

This work is part of the "lightweight instrumentation" RFC: https://groups.google.com/g/llvm-dev/c/r03Z6JoN7d4

This was first landed in https://reviews.llvm.org/D114566 but had to be reverted due to build errors.

Reviewed By: kyulee

Differential Revision: https://reviews.llvm.org/D115915
2021-12-17 10:45:59 -08:00
Ellis Hoag bdc68ee70f Revert "[InstrProf] Add Correlator class to read debug info"
Also reverts an attempt to fix the build errors https://reviews.llvm.org/D115911

The original diff https://reviews.llvm.org/D114566 causes some build
errors that I need to investigate.

https://lab.llvm.org/buildbot/#/builders/118/builds/7037

This reverts commit 95946d2f85.

Reviewed By: kyulee

Differential Revision: https://reviews.llvm.org/D115913
2021-12-16 16:28:19 -08:00
Ellis Hoag 01525da853 [InstrProf] Fix build error in Correlator class
For some reason this did not fail to compile for me locally, but did
fail on one of the builders. Here is the error:

https://lab.llvm.org/buildbot/#/builders/58/builds/14969
```
/home/buildbot/as-builder-4/lld-x86_64-ubuntu-fast/llvm-project/llvm/lib/ProfileData/InstrProfCorrelator.cpp: In static member function ‘static llvm::Expected<std::unique_ptr<llvm::InstrProfCorrelator::Context> > llvm::InstrProfCorrelator::Context::get(std::unique_ptr<llvm::MemoryBuffer>, const llvm::object::ObjectFile&)’:
/home/buildbot/as-builder-4/lld-x86_64-ubuntu-fast/llvm-project/llvm/lib/ProfileData/InstrProfCorrelator.cpp:44:10: error: could not convert ‘C’ from ‘std::unique_ptr<llvm::InstrProfCorrelator::Context>’ to ‘llvm::Expected<std::unique_ptr<llvm::InstrProfCorrelator::Context> >’
   return C;
```

Reviewed By: kyulee

Differential Revision: https://reviews.llvm.org/D115911
2021-12-16 15:59:12 -08:00
Ellis Hoag 95946d2f85 [InstrProf] Add Correlator class to read debug info
Extend `llvm-profdata` to read in a `.proflite` file and also a debug info file to generate a normal `.profdata` profile. This reduces the binary size by 8.4% when building an instrumented Clang binary without value profiling (164 MB vs 179 MB).

This work is part of the "lightweight instrumentation" RFC: https://groups.google.com/g/llvm-dev/c/r03Z6JoN7d4

Reviewed By: kyulee

Differential Revision: https://reviews.llvm.org/D114566
2021-12-16 15:18:12 -08:00