diff --git a/lib/Transforms/Scalar/LICM.cpp b/lib/Transforms/Scalar/LICM.cpp index a24b366e8d9..7ca9be01359 100644 --- a/lib/Transforms/Scalar/LICM.cpp +++ b/lib/Transforms/Scalar/LICM.cpp @@ -447,6 +447,8 @@ void LICM::sink(Instruction &I) { if (!isExitBlockDominatedByBlockInLoop(ExitBlocks[0], I.getParent())) { // Instruction is not used, just delete it. CurAST->deleteValue(&I); + if (!I.use_empty()) // If I has users in unreachable blocks, eliminate. + I.replaceAllUsesWith(UndefValue::get(I.getType())); I.eraseFromParent(); } else { // Move the instruction to the start of the exit block, after any PHI @@ -460,6 +462,8 @@ void LICM::sink(Instruction &I) { } else if (ExitBlocks.size() == 0) { // The instruction is actually dead if there ARE NO exit blocks. CurAST->deleteValue(&I); + if (!I.use_empty()) // If I has users in unreachable blocks, eliminate. + I.replaceAllUsesWith(UndefValue::get(I.getType())); I.eraseFromParent(); } else { // Otherwise, if we have multiple exits, use the PromoteMem2Reg function to