[LLVMdev] Detailed help with cloning the basic blocks of a function

[Nick Lewycky]

guyadini wrote:
>
> Hi,
>
> Thank you guys for helping me out with my previous questions.
> I am new to LLVM, and I'm getting stuck trying to do some basic stuff:
>
> Currently, I'm trying to move all the basic blocks of one function into
> another one,
> and at some point insert a branch into the moved function's entry point.
>
> The best way which I've found is to use CloneBasicBlock (from Cloning.h).
> However, I don't know how to get the cloned basic block not to use the
> values
> of the old basic block. I realize that it has something to do with the
> ValueMap that I pass
> to the function, but I'm not sure how to use it.
>
> Can someone please show me a short code snippet which does that sort of
> thing?
> It would really help me a lot.
>
> Also, if someone here has an idea for a better way of doing what I'm doing
> (copying/moving
> the basics blocks of one function into another), I'd love to hear that.

If you want to move all basic blocks out of one function into another, use:

   NewFunc->getBasicBlockList().splice(NewFunc->begin(), 
OldFunc->getBasicBlockList());

This will leave OldFunc empty.

Nick