diff options
Diffstat (limited to 'llvm/lib/Transforms')
| -rw-r--r-- | llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp | 6 | ||||
| -rw-r--r-- | llvm/lib/Transforms/Scalar/SCCP.cpp | 23 |
2 files changed, 26 insertions, 3 deletions
diff --git a/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp b/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp index 2aab79e89078..7eaa28bd1320 100644 --- a/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp +++ b/llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp @@ -2488,8 +2488,12 @@ Value *InstCombinerImpl::matchSelectFromAndOr(Value *A, Value *C, Value *B, // not create unnecessary casts if the types already match. Type *SelTy = A->getType(); if (auto *VecTy = dyn_cast<VectorType>(Cond->getType())) { + // For a fixed or scalable vector get N from <{vscale x} N x iM> unsigned Elts = VecTy->getElementCount().getKnownMinValue(); - Type *EltTy = Builder.getIntNTy(SelTy->getPrimitiveSizeInBits() / Elts); + // For a fixed or scalable vector, get the size in bits of N x iM; for a + // scalar this is just M. + unsigned SelEltSize = SelTy->getPrimitiveSizeInBits().getKnownMinSize(); + Type *EltTy = Builder.getIntNTy(SelEltSize / Elts); SelTy = VectorType::get(EltTy, VecTy->getElementCount()); } Value *BitcastC = Builder.CreateBitCast(C, SelTy); diff --git a/llvm/lib/Transforms/Scalar/SCCP.cpp b/llvm/lib/Transforms/Scalar/SCCP.cpp index c34da51e6dc1..fa1cfc84e4fd 100644 --- a/llvm/lib/Transforms/Scalar/SCCP.cpp +++ b/llvm/lib/Transforms/Scalar/SCCP.cpp @@ -342,7 +342,8 @@ static void findReturnsToZap(Function &F, } static bool removeNonFeasibleEdges(const SCCPSolver &Solver, BasicBlock *BB, - DomTreeUpdater &DTU) { + DomTreeUpdater &DTU, + BasicBlock *&NewUnreachableBB) { SmallPtrSet<BasicBlock *, 8> FeasibleSuccessors; bool HasNonFeasibleEdges = false; for (BasicBlock *Succ : successors(BB)) { @@ -385,6 +386,23 @@ static bool removeNonFeasibleEdges(const SCCPSolver &Solver, BasicBlock *BB, } else if (FeasibleSuccessors.size() > 1) { SwitchInstProfUpdateWrapper SI(*cast<SwitchInst>(TI)); SmallVector<DominatorTree::UpdateType, 8> Updates; + + // If the default destination is unfeasible it will never be taken. Replace + // it with a new block with a single Unreachable instruction. + BasicBlock *DefaultDest = SI->getDefaultDest(); + if (!FeasibleSuccessors.contains(DefaultDest)) { + if (!NewUnreachableBB) { + NewUnreachableBB = + BasicBlock::Create(DefaultDest->getContext(), "default.unreachable", + DefaultDest->getParent(), DefaultDest); + new UnreachableInst(DefaultDest->getContext(), NewUnreachableBB); + } + + SI->setDefaultDest(NewUnreachableBB); + Updates.push_back({DominatorTree::Delete, BB, DefaultDest}); + Updates.push_back({DominatorTree::Insert, BB, NewUnreachableBB}); + } + for (auto CI = SI->case_begin(); CI != SI->case_end();) { if (FeasibleSuccessors.contains(CI->getCaseSuccessor())) { ++CI; @@ -532,8 +550,9 @@ bool llvm::runIPSCCP( NumInstRemoved += changeToUnreachable(F.front().getFirstNonPHI(), /*PreserveLCSSA=*/false, &DTU); + BasicBlock *NewUnreachableBB = nullptr; for (BasicBlock &BB : F) - MadeChanges |= removeNonFeasibleEdges(Solver, &BB, DTU); + MadeChanges |= removeNonFeasibleEdges(Solver, &BB, DTU, NewUnreachableBB); for (BasicBlock *DeadBB : BlocksToErase) DTU.deleteBB(DeadBB); |