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messn036's avatar
messn036
Icon for New Contributor rankNew Contributor
4 years ago
Solved

Sample project with RTL module library not working

Hello Intel Support, I am attempting to compile a library of RTL components to use in my HLS project. The HLS project compiles when testing for x86-64 simulation, but the compiler complains about...
  • messn036's avatar
    messn036
    4 years ago

    The issue is in my expHBU.h file. I put

    uint8_t expHBU(uint8_t input);

    Rather than the CORRECT

    extern "C" {
    uint8_t expHBU(uint8_t input);
}

    This extern is extremely esoteric and should be included in the reference manual.

YoshiakiS_Altera's avatar
YoshiakiS_Altera
Icon for Occasional Contributor rankOccasional Contributor
4 years ago

Hello messn036,

Thank you for sharing the failure log with us.

I think the simple design is necessary to investigate it for us.

So could you share simple full design which can duplicate the error with us?

Best regards,

Yoshiaki Saito

messn036's avatar
messn036
Icon for New Contributor rankNew Contributor
4 years ago

Here are the source files I am using. I am trying to model the basic rtl library tutorial the best I can (which compiles fine in my environment). I'm sure its some easy syntax error that none of the compilers or packagers is catching.

I cannot upload the .cpp and .h files because this site rejects them. Here is the source

expHBU.h

#include <stdint.h>
#include "HLS/math.h"
uint8_t expHBU(uint8_t input);

expHBU.cpp

#include "expHBU.h"

uint8_t expHBU(uint8_t input){
    return (uint8_t)exp(input);
}

component_testbench.cpp

#include "HLS/hls.h"
#include "HLS/stdio.h"
#include "HLS/math.h"
#include "expHBU.h"


component uint8_t executeexp(uint8_t exponent)
{
    return expHBU(exponent);
}
component uint8_t executeexp_basic(uint8_t exponent)
{
    return exp(exponent);
}

int main()
{   
    uint8_t exponent = 3;
    uint8_t result = executeexp(exponent);
    printf("result %d \n", result);
    return 0;
}

Reminder: the x86 simulation works, but the FPGA compile does NOT

Thanks,

messn036

  • messn036's avatar
    messn036
    Icon for New Contributor rankNew Contributor
    4 years ago

    The issue is in my expHBU.h file. I put

    uint8_t expHBU(uint8_t input);

    Rather than the CORRECT

    extern "C" {
    uint8_t expHBU(uint8_t input);
}

    This extern is extremely esoteric and should be included in the reference manual.

    • YoshiakiS_Altera's avatar
      YoshiakiS_Altera
      Icon for Occasional Contributor rankOccasional Contributor
      4 years ago

      Hello messn036,

      Thank you for the update.

      Basically, you need to add the extern “C” to call a function from C++ to C. This is general rule of C++.

      C++ Language adds a prefix to a function name to support the class feature.

      But, this feature is disabled when you add extern “C”.

      So many C/C++ headers include:

      #ifdef __cplusplus
extern "C" {
#endif

rtl_inet_uint16 rtl_htons(rtl_inet_uint16 hostshort);
rtl_inet_uint16 rtl_ntohs(rtl_inet_uint16 netshort);
rtl_inet_uint32 rtl_htonl(rtl_inet_uint32 hostlong);
rtl_inet_uint32 rtl_ntohl(rtl_inet_uint32 netlong);

#ifdef __cplusplus
}
#endif

      Best regards,

      Yoshiaki Saito

      • YoshiakiS_Altera's avatar
        YoshiakiS_Altera
        Icon for Occasional Contributor rankOccasional Contributor
        4 years ago

        Hello messn036,

        I will close this thread if no further questions from you.

        Best regards,

        Yoshiaki Saito