[llvm] [NFC][PGO] Factor downscaling of branch weights out of `Instrumentation` into `ProfileData` (PR #153735)

Thu Aug 14 22:49:02 PDT 2025

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `llvm-clang-x86_64-sie-ubuntu-fast` running on `sie-linux-worker` while building `llvm` at step 5 "build-unified-tree".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/144/builds/32863

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 5 (build-unified-tree) failure: build (failure)
...
0.026 [1542/14/9] Building CommentCommandInfo.inc...
0.026 [1542/13/10] Building CommentCommandList.inc...
0.028 [1539/12/11] Building StmtDataCollectors.inc...
0.028 [1539/11/12] Building BuiltinTemplates.inc...
0.040 [206/14/13] Generating VCSRevision.h
0.066 [179/40/14] Building Opcodes.inc...
0.075 [170/40/15] Linking CXX executable bin/llvm-config
0.090 [169/40/16] Generating VCSVersion.inc
0.198 [168/40/17] Building OpenCLBuiltins.inc...
2.418 [165/40/18] Building CXX object lib/IR/CMakeFiles/LLVMCore.dir/ProfDataUtils.cpp.o
FAILED: lib/IR/CMakeFiles/LLVMCore.dir/ProfDataUtils.cpp.o 
CCACHE_CPP2=yes CCACHE_HASHDIR=yes CCACHE_SLOPPINESS=pch_defines,time_macros /usr/bin/ccache /usr/bin/g++ -DGTEST_HAS_RTTI=0 -D_DEBUG -D_GLIBCXX_ASSERTIONS -D_GNU_SOURCE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/lib/IR -I/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/llvm-project/llvm/lib/IR -I/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/build/include -I/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/llvm-project/llvm/include -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror=date-time -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wno-missing-field-initializers -pedantic -Wno-long-long -Wimplicit-fallthrough -Wno-uninitialized -Wno-nonnull -Wno-class-memaccess -Wno-redundant-move -Wno-pessimizing-move -Wno-noexcept-type -Wdelete-non-virtual-dtor -Wsuggest-override -Wno-comment -Wno-misleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -ffunction-sections -fdata-sections -O3 -DNDEBUG  -fno-exceptions -funwind-tables -fno-rtti -UNDEBUG -std=c++17 -MD -MT lib/IR/CMakeFiles/LLVMCore.dir/ProfDataUtils.cpp.o -MF lib/IR/CMakeFiles/LLVMCore.dir/ProfDataUtils.cpp.o.d -o lib/IR/CMakeFiles/LLVMCore.dir/ProfDataUtils.cpp.o -c /home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/llvm-project/llvm/lib/IR/ProfDataUtils.cpp
/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/llvm-project/llvm/lib/IR/ProfDataUtils.cpp: In function ‘llvm::SmallVector<unsigned int> llvm::downscaleWeights(llvm::ArrayRef<long unsigned int>, std::optional<long unsigned int>)’:
/home/buildbot/buildbot-root/llvm-clang-x86_64-sie-ubuntu-fast/llvm-project/llvm/lib/IR/ProfDataUtils.cpp:282:10: error: could not convert ‘DownscaledWeights’ from ‘SmallVector<[...],4>’ to ‘SmallVector<[...],12>’
  282 |   return DownscaledWeights;
      |          ^~~~~~~~~~~~~~~~~
      |          |
      |          SmallVector<[...],4>
3.121 [165/39/19] Building CXX object lib/IR/CMakeFiles/LLVMCore.dir/MDBuilder.cpp.o
3.340 [165/38/20] Building CXX object lib/Transforms/Utils/CMakeFiles/LLVMTransformUtils.dir/MisExpect.cpp.o
4.505 [165/37/21] Building CXX object lib/Transforms/Utils/CMakeFiles/LLVMTransformUtils.dir/ProfileVerify.cpp.o
4.828 [165/36/22] Building CXX object lib/Transforms/Utils/CMakeFiles/LLVMTransformUtils.dir/Instrumentation.cpp.o
6.199 [165/35/23] Building CXX object lib/CodeGen/CMakeFiles/LLVMCodeGen.dir/MachineCFGPrinter.cpp.o
6.664 [165/34/24] Building CXX object lib/CodeGen/CMakeFiles/LLVMCodeGen.dir/SanitizerBinaryMetadata.cpp.o
6.768 [165/33/25] Building CXX object lib/IR/CMakeFiles/LLVMCore.dir/Function.cpp.o
6.875 [165/32/26] Building CXX object lib/IR/CMakeFiles/LLVMCore.dir/Instruction.cpp.o
6.932 [165/31/27] Building CXX object lib/Transforms/Instrumentation/CMakeFiles/LLVMInstrumentation.dir/CGProfile.cpp.o
7.964 [165/30/28] Building CXX object lib/Transforms/Instrumentation/CMakeFiles/LLVMInstrumentation.dir/SanitizerBinaryMetadata.cpp.o
8.733 [165/29/29] Building CXX object lib/Transforms/Scalar/CMakeFiles/LLVMScalarOpts.dir/JumpTableToSwitch.cpp.o
8.938 [165/28/30] Building CXX object lib/Transforms/Instrumentation/CMakeFiles/LLVMInstrumentation.dir/NumericalStabilitySanitizer.cpp.o
9.226 [165/27/31] Building CXX object lib/Transforms/Utils/CMakeFiles/LLVMTransformUtils.dir/LoopUnrollRuntime.cpp.o
9.228 [165/26/32] Building CXX object lib/Transforms/Utils/CMakeFiles/LLVMTransformUtils.dir/LoopRotationUtils.cpp.o
9.472 [165/25/33] Building CXX object lib/Transforms/Instrumentation/CMakeFiles/LLVMInstrumentation.dir/SanitizerCoverage.cpp.o
9.560 [165/24/34] Building CXX object lib/Transforms/Instrumentation/CMakeFiles/LLVMInstrumentation.dir/ThreadSanitizer.cpp.o
10.014 [165/23/35] Building CXX object lib/Transforms/Utils/CMakeFiles/LLVMTransformUtils.dir/LoopPeel.cpp.o
10.039 [165/22/36] Building CXX object lib/IR/CMakeFiles/LLVMCore.dir/Instructions.cpp.o
10.120 [165/21/37] Building CXX object lib/Transforms/Scalar/CMakeFiles/LLVMScalarOpts.dir/JumpThreading.cpp.o
10.864 [165/20/38] Building CXX object lib/Transforms/Instrumentation/CMakeFiles/LLVMInstrumentation.dir/GCOVProfiling.cpp.o
11.416 [165/19/39] Building CXX object lib/Transforms/Utils/CMakeFiles/LLVMTransformUtils.dir/LoopUtils.cpp.o
11.542 [165/18/40] Building CXX object lib/Transforms/Instrumentation/CMakeFiles/LLVMInstrumentation.dir/IndirectCallPromotion.cpp.o
11.805 [165/17/41] Building CXX object lib/Transforms/Instrumentation/CMakeFiles/LLVMInstrumentation.dir/InstrProfiling.cpp.o
11.953 [165/16/42] Building CXX object lib/Transforms/Instrumentation/CMakeFiles/LLVMInstrumentation.dir/ControlHeightReduction.cpp.o
12.003 [165/15/43] Building CXX object lib/CodeGen/CMakeFiles/LLVMCodeGen.dir/SelectOptimize.cpp.o
12.060 [165/14/44] Building CXX object lib/Transforms/Instrumentation/CMakeFiles/LLVMInstrumentation.dir/HWAddressSanitizer.cpp.o
12.634 [165/13/45] Building CXX object lib/Transforms/Instrumentation/CMakeFiles/LLVMInstrumentation.dir/DataFlowSanitizer.cpp.o
12.645 [165/12/46] Building CXX object lib/Transforms/Utils/CMakeFiles/LLVMTransformUtils.dir/Local.cpp.o
13.413 [165/11/47] Building CXX object lib/Transforms/Instrumentation/CMakeFiles/LLVMInstrumentation.dir/AddressSanitizer.cpp.o
13.471 [165/10/48] Building CXX object lib/Transforms/Instrumentation/CMakeFiles/LLVMInstrumentation.dir/MemorySanitizer.cpp.o
14.455 [165/9/49] Building CXX object lib/IR/CMakeFiles/LLVMCore.dir/Verifier.cpp.o

```

</details>

https://github.com/llvm/llvm-project/pull/153735