creating function pointers

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1

Hi,

How do I create function pointers in LLVM? Is it possible to assign a
function to a function pointer?

Thanks

2

This is really easy with LLVM: a Function *is* a function pointer. Thus the following is perfectly legal:

%FP = global void ()* null

implementation

void %func() {
         store void ()* %func, void ()** %FP
         call void %caller( void ()* %func )
         ret void
}

void %caller(void ()* %fp2) {
         call void %fp2( )
         ret void
}

... etc. You can even play fun games that you can't in C (at least without casting). For example, you can have a function return a pointer to itself:

%FPTy = type %FPTy* ()

implementation

%FPTy* %func() {
         ret %FPTy* %func
}

-Chris