Author: Sanjay Patel Date: 2020-11-29T09:55:04-05:00 New Revision: ce134da4b18c27bbeba4e32f5813b1a3b043066e
URL: https://github.com/llvm/llvm-project/commit/ce134da4b18c27bbeba4e32f5813b1a3b043066e DIFF: https://github.com/llvm/llvm-project/commit/ce134da4b18c27bbeba4e32f5813b1a3b043066e.diff LOG: [IR] simplify code in removePredecessor(); NFCI As suggested in D92247 (and independent of whatever we decide to do there), this code is confusing as-is. Hopefully, this is at least mildly better. We might be able to do better still, but we have a function called "removePredecessor" with this behavior: "Note that this function does not actually remove the predecessor." (!) Added: Modified: llvm/lib/IR/BasicBlock.cpp Removed: ################################################################################ diff --git a/llvm/lib/IR/BasicBlock.cpp b/llvm/lib/IR/BasicBlock.cpp index 31666265b504..3268641ddf19 100644 --- a/llvm/lib/IR/BasicBlock.cpp +++ b/llvm/lib/IR/BasicBlock.cpp @@ -327,21 +327,19 @@ void BasicBlock::removePredecessor(BasicBlock *Pred, // Return early if there are no PHI nodes to update. if (!isa<PHINode>(begin())) return; - unsigned NumPreds = cast<PHINode>(front()).getNumIncomingValues(); - // Update all PHI nodes. - for (iterator II = begin(); isa<PHINode>(II);) { - PHINode *PN = cast<PHINode>(II++); - PN->removeIncomingValue(Pred, !KeepOneInputPHIs); - if (!KeepOneInputPHIs) { - // If we have a single predecessor, removeIncomingValue erased the PHI - // node itself. - if (NumPreds > 1) { - if (Value *PNV = PN->hasConstantValue()) { - // Replace the PHI node with its constant value. - PN->replaceAllUsesWith(PNV); - PN->eraseFromParent(); - } + unsigned NumPreds = cast<PHINode>(front()).getNumIncomingValues(); + for (PHINode &Phi : make_early_inc_range(phis())) { + Phi.removeIncomingValue(Pred, !KeepOneInputPHIs); + if (KeepOneInputPHIs) + continue; + // If we have a single predecessor, removeIncomingValue erased the PHI + // node itself. + // Try to replace the PHI node with a constant value. + if (NumPreds > 1) { + if (Value *PhiConstant = Phi.hasConstantValue()) { + Phi.replaceAllUsesWith(PhiConstant); + Phi.eraseFromParent(); } } } _______________________________________________ llvm-branch-commits mailing list llvm-branch-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/llvm-branch-commits
