HCC : An open source C++ compiler for heterogeneous devices

This repository hosts HCC compiler implementation project. The goal is to implement a compiler that takes a program conforming parallel programming standards such as C++ AMP, HC, C++ 17 ParallelSTL, or OpenMP and transforms it into AMD GCN ISA.

The project is based on LLVM+CLANG. For more information, please visit the hcc wiki:

https://github.com/RadeonOpenCompute/hcc/wiki

Git submodules

The project now employs git submodules to manage external components it depends upon. It it advised to add --recursive when you clone the project so all submodules are fetched automatically.

For example:

# automatically fetches all submodules
git clone --recursive -b clang_tot_upgrade https://github.com/RadeonOpenCompute/hcc.git

For more information about git submodules, please refer to git documentation.

Device libraries

HCC device library is a part of ROCm-Device-Libs. When compiling device code with hcc, rocm-device-libs package needs to be installed.

In case rocm-device-libs package is not present, you are required to build it from source. Please refer to ROCm-Device-Libs build procedure for more details.

Once it's built, run make install and config ToT HCC like:

cmake \
    -DCMAKE_BUILD_TYPE=Release \
    -DHSA_AMDGPU_GPU_TARGET=<AMD GPU ISA version string> \
    -DROCM_DEVICE_LIB_DIR=<where bitcodes of ROCm-Device-Libs are> \
    <ToT HCC checkout directory>

An example would be:

# Use AMD:AMDGPU:8:0:3 AMD GPU ISA
# ROCm-Device-Libs is built at ~/ocml/build , bitcodes are at
# ~/ocml/build/dist/lib
cmake \
    -DCMAKE_BUILD_TYPE=Release \
    -DHSA_AMDGPU_GPU_TARGET=AMD:AMDGPU:8:0:3 \
    -DROCM_DEVICE_LIB_DIR=~/ocml/build/dist/lib \
    ..

Multiple ISA

HCC now supports having multiple GCN ISAs in one executable file. You can do it in different ways:

use --amdgpu-target= command line option

It's possible to specify multiple --amdgpu-target= option. Example:

# ISA for Hawaii(7:0:1), Carrizo(8:0:1), Fiji(8:0:3) would be produced
hcc `hcc-config --cxxflags --ldflags` \
    --amdgpu-target=AMD:AMDGPU:7:0:1 \
    --amdgpu-target=AMD:AMDGPU:8:0:1 \
    --amdgpu-target=AMD:AMDGPU:8:0:3 \
    foo.cpp

use HCC_AMDGPU_TARGET env var

Use , to delimit each AMDGPU target in HCC. Example:

export HCC_AMDGPU_TARGET=AMD:AMDGPU:7:0:1,AMD:AMDGPU:8:0:1,AMD:AMDGPU:8:0:3
# ISA for Hawaii(7:0:1), Carrizo(8:0:1), Fiji(8:0:3) would be produced
hcc `hcc-config --cxxflags --ldflags` foo.cpp

configure HCC use CMake HSA_AMDGPU_GPU_TARGET variable

If you build HCC from source, it's possible to configure it to automatically produce multiple ISAs via HSA_AMDGPU_GPU_TARGET CMake variable.

Use ; to delimit each AMDGPU target. Example:

# ISA for Hawaii(7:0:1), Carrizo(8:0:1), Fiji(8:0:3) be configured by default
cmake \
    -DCMAKE_BUILD_TYPE=Release \
    -DROCM_DEVICE_LIB_DIR=~hcc/ROCm-Device-Libs/build/dist/lib \
    -DHSA_AMDGPU_GPU_TARGET="AMD:AMDGPU:7:0:1;AMD:AMDGPU:8:0:1;AMD:AMDGPU:8:0:3" \
    ../hcc