Why a condition like If (~Input) changes to a complex condition with ternary operator ?

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When I am trying to generate C code with Embedded Coder, the following condition
if (~Input)
is converted to the following ugly condition
if ((boolean_T)((int32_T)((Input ? ((int32_T)1) : ((int32_T)0)) ^ 1))) {
Is there any option to change in the setting to avoid this type of code being generated?
Is there a reason why this code would be generated instead of a simpler alternative?
The same code is generated if I change the condition to:
if (false == Input)
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Accepted Answer

Miguel
Miguel on 1 Dec 2022
Thanks everybody to take the time to review the question.
After reviewing all the possible options in the Code Generator and comparing one configuration that generated the ugly code vs a new one that didn't generate it, It was found that the parameter responsible for the ugly code is:
The ugly code is generated when it is set to "Bitwise operator"

More Answers (1)

Les Beckham
Les Beckham on 1 Dec 2022
So, the original condition if (~Input) is C code and not Matlab code? If so, you should use the logical not operator which is ! in C instead of ~ (as it is in Matlab).
~false in C will be 0xFFFFFFFE (or similar) and the ugly ternary expression coerces that back to a 1.
BTW - please post comments as comments rather than answers.
  3 Comments
Miguel
Miguel on 1 Dec 2022
The original code was Matlab code. The "Input" variable type was inherited from simulink and it was of type boolean. The code is in a Matlab function inside of a simulink model.
In the generated C code, the "Input" variable was of type "boolean_T".

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