From f73c8a06a97748030b36d394db3cee2560968348 Mon Sep 17 00:00:00 2001 From: Kyle Butt Date: Wed, 28 Jun 2017 01:41:25 +0000 Subject: [PATCH] Inlining: Don't re-map simplified cloned instructions. When simplifying an instruction that has been re-mapped, it should never simplify to an instruction in the original function. In the edge case where we are inlining a function into itself, the existing code led to incorrect behavior. Replace the incorrect code with an assert verifying that we never expect simplification to produce an instruction in the old function, unless the functions are the same. Differential Revision: https://reviews.llvm.org/D33850 llvm-svn: 306495 --- llvm/lib/Transforms/Utils/CloneFunction.cpp | 9 +++++---- 1 file changed, 5 insertions(+), 4 deletions(-) diff --git a/llvm/lib/Transforms/Utils/CloneFunction.cpp b/llvm/lib/Transforms/Utils/CloneFunction.cpp index 314c990293cc5..b61017f37ca98 100644 --- a/llvm/lib/Transforms/Utils/CloneFunction.cpp +++ b/llvm/lib/Transforms/Utils/CloneFunction.cpp @@ -325,10 +325,11 @@ void PruningFunctionCloner::CloneBlock(const BasicBlock *BB, // the basic block. if (Value *V = SimplifyInstruction(NewInst, BB->getModule()->getDataLayout())) { - // On the off-chance that this simplifies to an instruction in the old - // function, map it back into the new function. - if (Value *MappedV = VMap.lookup(V)) - V = MappedV; + assert((!isa(V) || + cast(V)->getParent() == nullptr || + cast(V)->getFunction() != OldFunc || + OldFunc == NewFunc) && + "Simplified Instruction should not be in the old function."); if (!NewInst->mayHaveSideEffects()) { VMap[&*II] = V;