Release Dependencies#

hipify-clang requires:

• CUDA, the latest supported version is 12.6.3, but requires at least version 7.0.

• LLVM+Clang version is determined at least partially by the CUDA version you are using, as shown in the table below. The recommended Clang release is the latest stable release 19.1.7, or at least version 4.0.0.

¹ Represents the latest supported and recommended configuration.

² Download the patch and unpack it into your LLVM distributive directory. This overwrites a few header files. You don’t need to rebuild LLVM.

³ Download the patch and unpack it into your LLVM source directory. This overwrites the Cuda.cpp file. You need to rebuild LLVM.

⁴ LLVM 3.x is no longer supported (but might still work).

In most cases, you can get a suitable version of LLVM+Clang with your package manager. However, you can also download a release archive and build or install it. In case of multiple versions of LLVM installed, set CMAKE_PREFIX_PATH so that CMake can find the desired version of LLVM. For example, -DCMAKE_PREFIX_PATH=D:\LLVM\19.1.7\dist.

Usage#

To process a file, hipify-clang needs access to the same headers that are required to compile it with Clang:

./hipify-clang square.cu --cuda-path=/usr/local/cuda-12.6 -I /usr/local/cuda-12.6/samples/common/inc

hipify-clang arguments are supplied first, followed by a separator -- and the arguments to be passed to Clang for compiling the input file:

./hipify-clang cpp17.cu --cuda-path=/usr/local/cuda-12.6 -- -std=c++17

hipify-clang also supports the hipification of multiple files that can be specified in a single command with absolute or relative paths:

./hipify-clang cpp17.cu ../../square.cu /home/user/cuda/intro.cu --cuda-path=/usr/local/cuda-12.6 -- -std=c++17

To use a specific version of LLVM during hipification, specify the hipify-clang option --clang-resource-directory= to point to the Clang resource directory, which is the parent directory for the include folder that contains __clang_cuda_runtime_wrapper.h and other header files used during the hipification process:

./hipify-clang square.cu --cuda-path=/usr/local/cuda-12.6 --clang-resource-directory=/usr/llvm/19.1.7/dist/lib/clang/19

For more information, refer to the Clang manual for compiling CUDA.

Using JSON compilation database#

For some hipification automation (starting from Clang 8.0.0), you can provide a Compilation Database in JSON format in the compile_commands.json file:

-p <folder containing compile_commands.json>
- or -
-p=<folder containing compile_commands.json>

You can provide the compilation database in the compile_commands.json file or generate using Clang based on CMake. You can specify multiple source files as well.

To provide Clang options, use compile_commands.json file, whereas to provide hipify-clang options, use the hipify-clang command line.

Here’s an example demonstrating the compile_commands.json usage:

[
  {
    "directory": "<test dir>",
    "command": "hipify-clang \"<CUDA dir>\" -I./include -v",
    "file": "cd_intro.cu"
  }
]

Hipification statistics#

The options --print-stats and --print-stats-csv provide an overview of what is hipified and what is not, as well as the hipification statistics. Use the --print-stats command to return the statistics as text to the terminal, or the --print-stats-csv command to create a CSV file to open in a spreadsheet.

hipify-clang intro.cu -cuda-path="C:/Program Files/NVIDIA GPU Computing Toolkit/CUDA/v12.6" --print-stats

[HIPIFY] info: file 'intro.cu' statistics:
CONVERTED refs count: 40
UNCONVERTED refs count: 0
CONVERSION %: 100.0
REPLACED bytes: 604
[HIPIFY] info: file 'intro.cu' statistics:
  CONVERTED refs count: 40
  UNCONVERTED refs count: 0
  CONVERSION %: 100.0
  REPLACED bytes: 604
  TOTAL bytes: 5794
  CHANGED lines of code: 34
  TOTAL lines of code: 174
  CODE CHANGED (in bytes) %: 10.4
  CODE CHANGED (in lines) %: 19.5
  TIME ELAPSED s: 0.41
[HIPIFY] info: CONVERTED refs by type:
  error: 2
  device: 2
  memory: 16
  event: 9
  thread: 1
  include_cuda_main_header: 1
  type: 2
  numeric_literal: 7
[HIPIFY] info: CONVERTED refs by API:
  CUDA Driver API: 1
  CUDA RT API: 39
[HIPIFY] info: CONVERTED refs by names:
  cuda.h: 1
  cudaDeviceReset: 1
  cudaError_t: 1
  cudaEventCreate: 2
  cudaEventElapsedTime: 1
  cudaEventRecord: 3
  cudaEventSynchronize: 3
  cudaEvent_t: 1
  cudaFree: 4
  cudaFreeHost: 3
  cudaGetDeviceCount: 1
  cudaGetErrorString: 1
  cudaGetLastError: 1
  cudaMalloc: 3
  cudaMemcpy: 6
  cudaMemcpyDeviceToHost: 3
  cudaMemcpyHostToDevice: 3
  cudaSuccess: 1
  cudaThreadSynchronize: 1

Print CSV statistics#

hipify-clang intro.cu -cuda-path="C:/Program Files/NVIDIA GPU Computing Toolkit/CUDA/v12.6" --print-stats-csv

This generates intro.cu.csv file with statistics: