diff options
Diffstat (limited to 'llvm/lib/CodeGen')
| -rw-r--r-- | llvm/lib/CodeGen/MachineInstr.cpp | 8 | ||||
| -rw-r--r-- | llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp | 5 |
2 files changed, 10 insertions, 3 deletions
diff --git a/llvm/lib/CodeGen/MachineInstr.cpp b/llvm/lib/CodeGen/MachineInstr.cpp index 17bd0f38964..26d58340b61 100644 --- a/llvm/lib/CodeGen/MachineInstr.cpp +++ b/llvm/lib/CodeGen/MachineInstr.cpp @@ -1312,9 +1312,11 @@ bool MachineInstr::isDereferenceableInvariantLoad(AliasAnalysis *AA) const { const MachineFrameInfo &MFI = getParent()->getParent()->getFrameInfo(); for (MachineMemOperand *MMO : memoperands()) { - if (MMO->isVolatile()) return false; - // TODO: Figure out whether isAtomic is really necessary (see D57601). - if (MMO->isAtomic()) return false; + if (!MMO->isUnordered()) + // If the memory operand has ordering side effects, we can't move the + // instruction. Such an instruction is technically an invariant load, + // but the caller code would need updated to expect that. + return false; if (MMO->isStore()) return false; if (MMO->isInvariant() && MMO->isDereferenceable()) continue; diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp index 3aedee8db0b..6d7f2840adf 100644 --- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp +++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGBuilder.cpp @@ -4564,6 +4564,11 @@ void SelectionDAGBuilder::visitAtomicLoad(const LoadInst &I) { auto Flags = MachineMemOperand::MOLoad; if (I.isVolatile()) Flags |= MachineMemOperand::MOVolatile; + if (I.getMetadata(LLVMContext::MD_invariant_load) != nullptr) + Flags |= MachineMemOperand::MOInvariant; + if (isDereferenceablePointer(I.getPointerOperand(), DAG.getDataLayout())) + Flags |= MachineMemOperand::MODereferenceable; + Flags |= TLI.getMMOFlags(I); MachineMemOperand *MMO = |
