llvm dev - Nov 2013 - [LLVMdev] Basic Block Predecessor

All,

Is there a fast way to retrieve all of the predecessors to a BasicBlock in
a function. Specifically, is there a fast way to iterate through all
BasicBlocks which can break to a specific BasicBlock?

Thanks,
Billy
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Hi Billy,
> Is there a fast way to retrieve all of the predecessors to a BasicBlock
> in a function. Specifically, is there a fast way to iterate through all
> BasicBlocks which can break to a specific BasicBlock?
CFG.h defines pred_iterator to do just this.  So after including 
llvm/Support/CFG.h you can iterate through the predecessors of a 
BasicBlock bb using something like

for (pred_iterator PI = pred_begin(bb), E = pred_end(bb); PI != E; ++PI) {
     ....
}

--Stephan