llvm-prof

this was copied form llvm release 3.3 include llvm-prof libLLVMProfiling.so libprofile_rt.so

because since llvm release 3.4 they remove profiling related code totaly, so this project would help you get the function back.

this also provide a inst-timing a simple program report all llvm ir's instruction's cpu timing and cycles.

build

$ sudo apt install llvm-3.5-dev clang-3.5 libopenmpi-dev gfortran # maybe mpi dependency could make a option.
$ mkdir build
$ cd build
$ cmake ..
$ # or cmake .. -DLLVM_RECOMMEND_VERSION=3.5 to look for llvm-config-3.5
$ make
$ sudo make install

compile option

• LLVM_RECOMMEND_VERSION : select which llvm version to build
• OUTPUT_HASPID : does llvmprof.out contain a pid for mpi program
• DYNAMIC_LINK : dynamic link LLVM single big shared object

argument

• -list-all : print out all outputs

• -value-content : print out traped value detail content instead of brief report

• -unsort : print out outputs without sort

• -diff : compare two output file and report whether they are different

  example: llvm-prof -diff a.out b.out

• -merge : merge a list of output file into one.

  example: llvm-prof -merge=sum generate.out *input.out

  option: -merge=none -merge=sum -merge=avg

• -to-block : convert edge profiling output to basicblock info format

  example: llvm-prof -to-block bitcode input.out output.out

• -timing : cacluating prog's execute timing from llvmprof.out and timing source support multi source, split by ':'

  example: llvm-prof -timing=lmbench bitcode prof.out lmbench.log

  example: llvm-prof -timing=lmbench:mpi bitcode prof.out lmbench.log mpi.log

  option: -timing=none -timing=lmbench -timing=mpi

environment variable

• PROFILING_OUTDIR : put all llvmprof.out.* to the dir

extra profilings

• ValueProfiling : provide value profiling, could trap some value.
• PredBlockProfiling : similar to edge profiling, different is it increase counter with a value, not 1. it is used in prediction block frequence.
• MPIProfiling : profiling for mpi call's count parameter

note

• you need add $PKG_CONFIG_PATH to let pkg-config recognise llvm-prof.pc
• If there is something wrong with mpi or gfortran when you compiling llvm-prof, you can try to install libopenmpi-dev and gfortran.