MATLAB: How to inline external C-Code with legacy code tool

simulink coder

I am calling external C functions via an S-function. The S-function is created using Legacy Code Tool (LCT), which also generates a TLC file.

Despite the TLC file, the external C code is not inlined when generating C code. What is the correct workflow to inline the external C code?

Best Answer

You can use #ifdef MATLAB_MEX_FILE pragma in your external header file to control compiler function inline process

Assume we would inline external code: myfoo.c, myfoo.h

Step 1: Add pragma to your external header file myfoo.h e.g.

#ifdef MATLAB_MEX_FILE  // This is for simulation only, we create empty functions
void myfoo(uint32_t instance, uint8_t channel);
#else                   // Code generation
#include "a.h"
#include "b.h"
static inline void myfoo(uint32_t instance, uint8_t channel)
{
    ...
}
#endif

Step 2: The myfoo.c contains this

#include "myfoo.h"
#ifdef MATLAB_MEX_FILE  // This is for simulation only, we create empty functions
void myfoo(uint32_t instance, uint8_t channel
{
}
#endif

In the model step function, the external code will be inlined after compiling code from your Simulink model.

Related Solutions

MATLAB: Calling an outside C function from a legacy_code block !

It was simple. All files must be added to the SourceFiles property.

What it was like before :

   def = legacy_code('initialize');
   def.SourceFiles = {'test.c'};

How it was modified in order to build properly :

   def = legacy_code('initialize');
   def.SourceFiles = {'test.c','test_sum.c'};

MATLAB: How to use “mexPrintf” for simulation and “printf” for code generation in a MATLAB Function Block using coder.ceval

You can use the "MATLAB_MEX_FILE" C preprocessor macro in your custom C code to determine whether you are compiling for a MEX target. For example, you can use this macro to define a custom "printOutput" function:

#include <stdio.h>
#include <stdlib.h>
#ifdef MATLAB_MEX_FILE
#include "mex.h"
#endif
void printOutput(const char* str);
#ifdef MATLAB_MEX_FILE
// Use the mexPrintf function
void printOutput(const char* str) {
    mexPrintf(str);
}
#else
// Use the standard C printf function
void printOutput(const char* str) {
    printf(str);
}
#endif

This function is defined to call "mexPrintf" when compiled for a MEX and "printf" otherwise.

Best Answer

Related Solutions

MATLAB: Calling an outside C function from a legacy_code block !

MATLAB: How to use “mexPrintf” for simulation and “printf” for code generation in a MATLAB Function Block using coder.ceval

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