[PATCH] D125426: Add a new flavor "BBLabels" to LLVM_BUILD_INSTRUMENTED

[Sriraman Tallam via Phabricator via llvm-commits]

tmsriram added a comment.

In D125426#3509699 <https://reviews.llvm.org/D125426#3509699>, @shenhan wrote:

> Here is the proposed workflow to build a propeller optimized clang binary (similar to PGO build).
>
> 1. Build instrumented clang binary:
>
> cmake -G Ninja ... -DLLVM_BUILD_INSTRUMENTED=BBLabels ... llvm-project/llvm
> ninja build
>
> 2. Using the above built binary in day-to-day routine and collect perf.data file and then convert it to propeller profiles.
>
> 3. Build the optimized clang binary:
>
> cmake -G Ninja ... -DLLVM_PROPELLER_PROFILES=<profile> ... llvm-project/llvm
>
> The experiment data show propeller optimized clang has a 5% compiler time improvement over PGO build.

Thanks! Please move this to the description.



================
Comment at: llvm/cmake/modules/HandleLLVMOptions.cmake:981
 
-set(LLVM_BUILD_INSTRUMENTED OFF CACHE STRING "Build LLVM and tools with PGO instrumentation. May be specified as IR or Frontend")
+set(LLVM_BUILD_INSTRUMENTED OFF CACHE STRING "Build LLVM and tools with instrumentation. Use IR, CSIR or Frontend for PGO. Use BBLabels for basic block sections instrumentation")
 set(LLVM_VP_COUNTERS_PER_SITE "1.5" CACHE STRING "Value profile counters to use per site for IR PGO with Clang")
----------------
Suggestion:  Maybe say "Use BBLabels for Propeller instrumentation via basic block labels"


Repository:
  rG LLVM Github Monorepo

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  https://reviews.llvm.org/D125426/new/

https://reviews.llvm.org/D125426