[PATCH] D157913: [Coverage] Allow Clang coverage to be used with debug info correlation.

phosek added a comment. We've been investigating a serious performance regression in our latest Clang roll that is affecting coverage. Whereas previously, we could process all coverage data in under an hour, now the job times out after 6 hours. After investigation, I found out that this change

[PATCH] D157913: [Coverage] Allow Clang coverage to be used with debug info correlation.

zequanwu added a comment. In D157913#4648313 , @ellis wrote: > I have seen that MachO sections remain in the header even if the size is zero > which seems to be the case here. You could use `llvm-objdump` to verify that > the section exists but the

[PATCH] D157913: [Coverage] Allow Clang coverage to be used with debug info correlation.

zequanwu added a comment. I feel like either this feature not working well with mac or we should keep `__llvm_prf_names` section in the binary. Current idea is to completely get rid of `__llvm_prf_names` section in the binary. Even if I fixed the issue https://reviews.llvm.org/D157913#4648296,

[PATCH] D157913: [Coverage] Allow Clang coverage to be used with debug info correlation.

ellis added a comment. In D157913#4648296 , @zequanwu wrote: > For some unknown reasons, linker still generates __llvm_prf_names section in > the final binary on mac even if the object file doesn't have this section. > And I cannot use llvm-objdump to

[PATCH] D157913: [Coverage] Allow Clang coverage to be used with debug info correlation.

zequanwu marked an inline comment as done. zequanwu added a comment. For some unknown reasons, linker still generates __llvm_prf_names section in the final binary on mac even if the object file doesn't have this section. And I cannot use llvm-objdump to get anything from that section. $

[PATCH] D157913: [Coverage] Allow Clang coverage to be used with debug info correlation.

zequanwu marked an inline comment as done. zequanwu added inline comments. Comment at: llvm/lib/ProfileData/InstrProfCorrelator.cpp:42 +const char *InstrProfCorrelator::CovFunctionNameAttributeName = +"Cov Function Name"; phosek wrote: > I missed this

[PATCH] D157913: [Coverage] Allow Clang coverage to be used with debug info correlation.

phosek added inline comments. Comment at: llvm/lib/ProfileData/InstrProfCorrelator.cpp:42 +const char *InstrProfCorrelator::CovFunctionNameAttributeName = +"Cov Function Name"; I missed this earlier, but I think that spelling this out in full, that is

[PATCH] D157913: [Coverage] Allow Clang coverage to be used with debug info correlation.

zequanwu added a comment. In D157913#4646718 , @thakis wrote: > Looks like this breaks check-clang on mac: > http://45.33.8.238/macm1/69297/step_7.txt > > Please take a look and revert for now if it takes a while to fix.

[PATCH] D157913: [Coverage] Allow Clang coverage to be used with debug info correlation.

thakis added a comment. Looks like this breaks check-clang on mac: http://45.33.8.238/macm1/69297/step_7.txt Please take a look and revert for now if it takes a while to fix. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D157913/new/

[PATCH] D157913: [Coverage] Allow Clang coverage to be used with debug info correlation.

This revision was landed with ongoing or failed builds. This revision was automatically updated to reflect the committed changes. Closed by commit rG32db121b29f7: [Coverage] Allow Clang coverage to be used with debug info correlation. (authored by zequanwu). Changed prior to commit:

[PATCH] D157913: [Coverage] Allow Clang coverage to be used with debug info correlation.

ellis accepted this revision. ellis added a comment. This revision is now accepted and ready to land. In D157913#4646201 , @zequanwu wrote: > In D157913#4646184 , @ellis wrote: > >> It looks like

[PATCH] D157913: [Coverage] Allow Clang coverage to be used with debug info correlation.

zequanwu added a comment. In D157913#4646184 , @ellis wrote: > It looks like `debug-info-correlate-coverage.ll` was renamed twice. Is this > intended? I just moved `llvm/test/Instrumentation/InstrProfiling/debug-info-correlate-coverage.ll.` to

[PATCH] D157913: [Coverage] Allow Clang coverage to be used with debug info correlation.

zequanwu updated this revision to Diff 556809. zequanwu marked 3 inline comments as done. zequanwu added a comment. Address comments. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D157913/new/ https://reviews.llvm.org/D157913 Files:

[PATCH] D157913: [Coverage] Allow Clang coverage to be used with debug info correlation.

ellis added a comment. It looks like `debug-info-correlate-coverage.ll` was renamed twice. Is this intended? Comment at: compiler-rt/lib/profile/InstrProfilingWriter.c:276-277 __llvm_profile_get_num_counters(CountersBegin, CountersEnd); - const uint64_t NamesSize =

[PATCH] D157913: [Coverage] Allow Clang coverage to be used with debug info correlation.

zequanwu updated this revision to Diff 556805. zequanwu added a comment. Remove profile name section. Unused coverage function names are stored in debug info as a fake global variable info: 0x000b: DW_TAG_compile_unit ... 0x0071: DW_TAG_variable DW_AT_name

[PATCH] D157913: [Coverage] Allow Clang coverage to be used with debug info correlation.

ellis added a comment. In D157913#4638845 , @zequanwu wrote: > In D157913#4638569 , @phosek wrote: > >> In D157913#4626007 , @zequanwu >> wrote: >> It seems that

[PATCH] D157913: [Coverage] Allow Clang coverage to be used with debug info correlation.

zequanwu added a comment. In D157913#4638569 , @phosek wrote: > In D157913#4626007 , @zequanwu > wrote: > >>> It seems that the `__llvm_prf_names` is retained in this mode. What is the >>> overhead of this

[PATCH] D157913: [Coverage] Allow Clang coverage to be used with debug info correlation.

phosek added a comment. In D157913#4626007 , @zequanwu wrote: >> It seems that the `__llvm_prf_names` is retained in this mode. What is the >> overhead of this section generally? Can we instead use debug info to lookup >> function names? > > With debug

[PATCH] D157913: [Coverage] Allow Clang coverage to be used with debug info correlation.

zequanwu added inline comments. Comment at: compiler-rt/test/profile/Darwin/coverage-debug-info-correlate.cpp:29 + +// RUN: llvm-cov report --instr-profile=%t.profdata %t | FileCheck %s -check-prefix=NONAME + ellis wrote: > Is it worth testing that

[PATCH] D157913: [Coverage] Allow Clang coverage to be used with debug info correlation.

zequanwu updated this revision to Diff 555889. zequanwu marked 4 inline comments as done. zequanwu added a comment. Address comments. Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D157913/new/ https://reviews.llvm.org/D157913 Files:

[PATCH] D157913: [Coverage] Allow Clang coverage to be used with debug info correlation.

ellis added a comment. In D157913#4626007 , @zequanwu wrote: >> It seems that the `__llvm_prf_names` is retained in this mode. What is the >> overhead of this section generally? Can we instead use debug info to lookup >> function names? > > With debug

[PATCH] D157913: [Coverage] Allow Clang coverage to be used with debug info correlation.

zequanwu added a comment. > It seems that the `__llvm_prf_names` is retained in this mode. What is the > overhead of this section generally? Can we instead use debug info to lookup > function names? With debug info correlation enabled, `__llvm_prf_names` section will only contain functions

[PATCH] D157913: [Coverage] Allow Clang coverage to be used with debug info correlation.

ellis added a comment. Thanks for working on this! I've added a few other reviewers that might be interested. In particular it might conflict with the stack D138846 IIRC It seems that the `__llvm_prf_names` is retained in this mode. What is the overhead of