Intel® High Level Synthesis Compiler Pro Edition: Reference Manual

ID 683349
Date 3/28/2022
Public

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2.3. Compiler Interoperability

You can compile your testbench code with GCC or Microsoft Visual Studio, but generating RTL and simulation support for your component always requires the Intel® HLS Compiler.
The following table shows which parts of your design you can compile with each compiler:
  GCC/MSVC i++
Testbench X X
Component (emulation) X X
Component (RTL)   X
Restriction: You cannot use GCC and Microsoft Visual Studio to compile code that uses any Intel® HLS Compiler provided header files other than HLS/hls.h. For some arbitrary precision data types, the Intel® HLS Compiler provides reference headers that can be compiled GCC and Microsoft Visual Studio along with the FPGA-optimized headers. For details, see Arbitrary Precision Math Support.

To see what versions of GCC and Microsoft Visual Studio the Intel® HLS Compiler supports, see " Intel® High Level Synthesis Compiler Prerequisites" in Intel® High Level Synthesis Compiler Getting Started Guide.

To use a native compiler (GCC or Microsoft Visual Studio) to compile your Intel® HLS Compiler code, you must run your native compiler from a terminal session where you initialized the environment for the Intel® HLS Compiler. The initialization script chooses the correct native compiler for you system.

GCC

To compile your Intel® HLS Compiler code with GCC:
  1. Initialize your environment with the Intel® HLS Compiler initialization script:
    <quartus_installdir>/hls/init_hls.sh
  2. Add the path to the Intel® HLS Compiler header files to the g++ command include path with the -l command option.

    The header files are in the quartus_installdir/hls/include directory.

  3. Add the path to the HLS emulation library to the linker search path with the -L command option.

    The emulation library is in the quartus_installdir/hls/host/linux64/lib directory.

  4. Add the hls_emul library to the linker command (that is, specify -lhls_emul as a command option).
  5. Ensure that you specify the -std=c++17 option of the g++ command.
  6. If you want to generate debug symbols, specify the -g option of the g++ command.
  7. If you are using HLS tasks in a system of tasks (ihc::launch and ihc:collect), specify the -pthread option of the g++ command.
  8. If you are using arbitrary precision datatypes, include the reference version in your source code instead of the FPGA-optimized version provided with the Intel® HLS Compiler. You can use the __INTELFPGA_COMPILER__ macro to control which variant is included. For example, if you are using arbitrary precision integers, you can use the following macro code
    #ifdef __INTELFPGA_COMPILER__ 
    #include "HLS/ac_int.h" 
    #else 
    #include "ref/ac_int.h" 
    #endif 
If you implement these steps, your g++ command resembles the following example command:
g++ myFile.cpp -g -I"$(HLS_INSTALL_DIR)/include" 
               -L"$(HLS_INSTALL_DIR)/host/linux64/lib" -lhls_emul 
               -pthread -std=c++17 

Microsoft Visual C++

The following instructions were tested with Microsoft Visual Studio 2017 Professional.

To compile your Intel® HLS Compiler code with Microsoft Visual C++:

  1. Initialize your environment with the Intel® HLS Compiler initialization script:
    <quartus_installdir>/hls/init_hls.bat
  2. Add the Intel® HLS Compiler header files to the compiler command include path with the /l command option.

    The header files are in the quartus_installdir\hls\include directory.

  3. Add the /Zi option to generate debug symbols when compiling.
  4. Add the /wd4068 option to suppress warnings because MSVC does not recognize the Intel® HLS Compiler pragmas.
  5. Add the HLS emulation library to the linker search path with the /libpath command option.

    The emulation library is in the quartus_installdir\hls\host\windows64\lib directory.

  6. Add the hls_emul library to the linker command.
  7. If you are using arbitrary precision datatypes, include the reference version instead of the FPGA-optimized version provided with the Intel® HLS Compiler. You can use the __INTELFPGA_COMPILER__ macro to control which version is included:
    #ifdef __INTELFPGA_COMPILER__ 
    #include "HLS/ac_int.h" 
    #else 
    #include "ref/ac_int.h" 
    #endif 
Your Microsoft Visual C++ compiler command should resemble the following example command:
cl myFile.cpp /I "%HLS_INSTALL_DIR%\include" /nologo /EHsc /wd4068 /MD 
              /std:c++17 /Zi 
              /link "/libpath:%HLS_INSTALL_DIR%\host\windows64\lib" 
              hls_emul.lib