Add Function Argument

The stack or a register is used to pass an argument to a function.
Define a new function argument with the appropriate type, making explicit that such stack position or register is used to hold the argument.

        ...
        eax = 1;
        loc100();
        ...
        
void loc100() {
        ...
        ... = eax;
        ...
        return;
}

⇓

        ...
        eax = 1;
        loc100(eax);
        ...
        
void loc100(int arg1) {
        ...
        ... = arg1;
        ...
        return;
}

Motivation

In a similar fashion as the function return value, it is a common calling convention to pass function arguments in particular registers, the stack, or both. This is platform-specific detail, which should be eliminated for attaining proper code understanding.

Mechanics

Add a new function argument with the appropriate type.
Add the register or stack location as argument to all function calls.
Replace all references to the register or stack location in the function body to the argument name.