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Diffstat (limited to 'include/llvm/Transforms/Utils/Local.h')
| -rw-r--r-- | include/llvm/Transforms/Utils/Local.h | 15 |
1 files changed, 15 insertions, 0 deletions
diff --git a/include/llvm/Transforms/Utils/Local.h b/include/llvm/Transforms/Utils/Local.h index 24be83cb3d..292af1dbfc 100644 --- a/include/llvm/Transforms/Utils/Local.h +++ b/include/llvm/Transforms/Utils/Local.h @@ -78,6 +78,21 @@ void RecursivelyDeleteDeadPHINode(PHINode *PN); // Control Flow Graph Restructuring. // +/// RemovePredecessorAndSimplify - Like BasicBlock::removePredecessor, this +/// method is called when we're about to delete Pred as a predecessor of BB. If +/// BB contains any PHI nodes, this drops the entries in the PHI nodes for Pred. +/// +/// Unlike the removePredecessor method, this attempts to simplify uses of PHI +/// nodes that collapse into identity values. For example, if we have: +/// x = phi(1, 0, 0, 0) +/// y = and x, z +/// +/// .. and delete the predecessor corresponding to the '1', this will attempt to +/// recursively fold the 'and' to 0. +void RemovePredecessorAndSimplify(BasicBlock *BB, BasicBlock *Pred, + TargetData *TD = 0); + + /// MergeBasicBlockIntoOnlyPred - BB is a block with one predecessor and its /// predecessor is known to have one successor (BB!). Eliminate the edge /// between them, moving the instructions in the predecessor into BB. This |