[Openmp-dev] when is offloading to NVIDIA targets available?

[Siegmar Gross via Openmp-dev]

Hi,

today I've built the latest version of llvm-trunk. I used the following
commands.

svn co http://llvm.org/svn/llvm-project/llvm/trunk llvm
cd llvm/tools
svn co http://llvm.org/svn/llvm-project/cfe/trunk clang
svn co http://llvm.org/svn/llvm-project/polly/trunk polly
svn co http://llvm.org/svn/llvm-project/lldb/trunk lldb
svn co http://llvm.org/svn/llvm-project/lld/trunk lld
cd clang/tools
svn co http://llvm.org/svn/llvm-project/clang-tools-extra/trunk/ extra
cd ../../../projects
svn co http://llvm.org/svn/llvm-project/compiler-rt/trunk compiler-rt
svn co http://llvm.org/svn/llvm-project/openmp/trunk openmp
svn co https://github.com/clang-ykt/openmp libomptarget
cd ../..

set LLVM_VERSION=llvm-trunk
rm -r build
mkdir build
cd build
cmake -DCMAKE_INSTALL_PREFIX:PATH=/usr/local/${LLVM_VERSION} \
   -GNinja \
   -DLLVM_TARGETS_TO_BUILD:STRING="NVPTX;X86" \
   -DCMAKE_BUILD_TYPE:STRING="Release" \
   -DLLVM_PARALLEL_COMPILE_JOBS:STRING="4" \
   -DLLVM_PARALLEL_LINK_JOBS:STRING="4" \
   -DCMAKE_C_COMPILER:STRING="/usr/local/gcc-6.4.0/bin/gcc" \
   -DCMAKE_C_FLAGS:STRING="-m64 -I/usr/local/valgrind/include 
-I/usr/include/ncurses" \
   -DCMAKE_C_STANDARD_LIBRARIES="-lpthread" \
   -DCMAKE_CXX_COMPILER:STRING="/usr/local/gcc-6.4.0/bin/g++" \
   -DCMAKE_CXX_FLAGS:STRING="-m64 -I/usr/local/valgrind/include 
-I/usr/include/ncurses" \
   -DCMAKE_CXX_STANDARD_LIBRARIES="-lpthread" \
   -DCMAKE_EXE_LINKER_FLAGS:STRING="-m64" \
   -DLLVM_LIBDIR_SUFFIX:STRING="64" \
   -DLLVM_POLLY_LINK_INTO_TOOLS:BOOL=ON \
 
-DLIBOMPTARGET_DEP_LIBELF_INCLUDE_DIR:STRING="/usr/local/elfutils-0.169/include" \
 
-DLIBOMPTARGET_DEP_LIBELF_LIBRARIES:STRING="/usr/local/elfutils-0.169/lib64/libelf.so" 
\
   -DLIBOMPTARGET_DEP_LIBFFI_INCLUDE_DIR:STRING="/usr/include" \
   -DLIBOMPTARGET_DEP_LIBFFI_LIBRARIES:STRING="/usr/lib64/libffi.so" \
   -DCUDA_INCLUDE_DIRS:STRING="/usr/local/cuda/include" \
   -DCUDA_LIBRARIES:STRING="/usr/local/cuda/lib64/libcudart.so" \
   -DBUILD_SHARED_LIBS:BOOL=ON \
   -DOPENMP_ENABLE_LIBOMPTARGET:BOOL=On \
   ../llvm \
   |& tee log.cmake


Unfortunately I still have the same problems which I reported in Bug 34104
nearly two months ago, if I try to offload to a NVIDIA target. I know that
OPENMP_ENABLE_LIBOMPTARGET isn't enabled by default at the moment.
Nevertheless, I would be grateful if somebody can tell me when offloading
to NVIDIA targets will be available. Does somebody know, why I get a wrong
value for the number of devices if I use the CPU version?

loki introduction 107 clang -fopenmp -fopenmp-targets=x86_64-pc-linux-gnu 
dot_prod_accelerator_OpenMP.c -lomptarget
loki introduction 108 a.out
Number of processors:     24
Number of devices:        4
Default device:           0
sum = 6.000000e+08

The output is wrong, because I have two six-core processors (24 hwthreads) and 
one NVIDIA GPU. gcc-7.1.0 reports correct values.

loki introduction 109 gcc -fopenmp dot_prod_accelerator_OpenMP.c 
          loki introduction 110 a.out
Number of processors:     24
Number of devices:        1
Default device:           0
sum = 6.000000e+08
loki introduction 111


Thank you very much for your help in advance.


Kind regards

Siegmar