How to make Embedded coder use isnan C-API than implementing custom code?

My Simulink model uses NaN and some places there is check of same using matlab function isnan().

When I am genertaing C-code using embedded coder, i see generated code has custom implementation of isnan function like below

/* Test if value is not a number */

boolean_T rtIsNaN(real_T value)

{

return (boolean_T)((value!=value) ? 1U : 0U);

}

How can I avoid this and allow EC to use isnan API from math.h from my toolchain. If I use above implementation, it doesnot work as expected in some of my cores which doesnt have FPU. Replacing this and Calling isnan() from math.h works fine for me.

I did web-search but couldnt find any help on this topic.

Answer 1

[Naman Bhaia]

I believe Code Replacement Customization can be the possible solution. To implement that, you could develop a code replacement library by referring to this link.

Answer 2

[Ritesh Rajore]

I tried this but it is not reflecting. I defined replacemnet function of rtIsNaN as isnan but I see EC is generating the code as earlier.

In my model, piece of code where nan and its validation is done is in m-file. Not sure if code replacement is applicable for m-file code.