KERnel Memory Accesses

Dependencies

Ubuntu 18.04 LTS

Only tested in 18.04. In principle it should work on higher versions too, but no guarantees

LLVM 10

Currently the build system does not automatically pull the LLVM dependencies so we need to manually install them

# Download precompiled LLVM 10 binaries
wget -c https://github.com/llvm/llvm-project/releases/download/llvmorg-10.0.0/clang+llvm-10.0.0-x86_64-linux-gnu-ubuntu-18.04.tar.xz
tar xf clang+llvm-10.0.0-x86_64-linux-gnu-ubuntu-18.04.tar.xz -C /my/llvm/install/dir --strip-components=1

# (Optional) Create `$LLVM_HOME` env var pointing to the llvm installation
echo -e export LLVM_HOME=$(realpath /my/llvm/install/dir) >> ~/.bashrc 
source ~/.bashrc

cxxtools

(we should really have CMake configure this but for now its ok)

sudo apt update
sudo apt install libcxxtools-dev

Optional Dependencies

Documentation

• dot
• Doxygen

sudo apt install graphviz
sudo apt install doxygen

Build

cd kerma
mkdir build
cd build && cmake ..
make -j4

If all went well there should be a directory out under build with the following structure:

out/
├── bin/
├── docs/
├── include/
├── lib/
└── rt/

This is the directory to use as KERMA_HOME in KermaView, meaning that in KermaView you should set KERMA_HOME=path/to/kerma/build/out in the .env file.

---

Cuda Instrumentation pipeline

                   +---------------+
                   |   Device IR   |
                   |Instrumentation|
                   +----+----+-----+
                        ^    |
                        |    |
                        |    |
                        |    |
          clang         +    v     llc                  ptxas             fatbinary
     +---------------> device.bc +-------> device.ptx +-------> device.o +---------> device.fatbin
     |                                                                                  +
     +                                                                                  |
program.cu                                                                              |
     +                                                                                  |
     |    clang                      clang             clang                            |
     +---------------> host.cu.inc +-------> host.bc +-------> host.o +---------------->+ clang (link)
                       (host src w.           +   ^                                     |
                        Cuda wrappers)        |   |                                     |
                                              |   |                                     v
                                              |   |                                  program.exe
                                              v   |
                                         +----+---+------+
                                         |    Host IR    |
                                         |Instrumentation|
                                         +----+---+------+

TODO: Add flags for each step

Notes

Steps

• Step 0

  clang++ -std=c++11 -c -S -g -O0 -emit-llvm -fno-discard-value-names      \
          -Xclang -disable-O0-optnone                                      \
          <file> -cuda-gpu-arch=<arch>
  

• Step 1

  opt -S -mem2reg -instnamer <file>.ll > <file>.1.ll
  

• Step 2

  opt -S -load <KermaTransformPlugin> --kerma-md --kerma-mi [<kerma-md options>] [<kerma-mi-options>] <file>.1.ll > <file>.2.ll
  

Passes to check

• https://llvm.org/doxygen/TargetLibraryInfo_8h_source.html