diff options
Diffstat (limited to 'lib/CodeGen/SelectionDAG/SelectionDAG.cpp')
| -rw-r--r-- | lib/CodeGen/SelectionDAG/SelectionDAG.cpp | 41 |
1 files changed, 23 insertions, 18 deletions
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp index 3ab0b46def..74500d517b 100644 --- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp +++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp @@ -3927,12 +3927,16 @@ SDValue SelectionDAG::getAtomic(unsigned Opcode, DebugLoc dl, EVT MemVT, Alignment = getEVTAlignment(MemVT); MachineFunction &MF = getMachineFunction(); - unsigned Flags = MachineMemOperand::MOLoad | MachineMemOperand::MOStore; + // All atomics are load and store, except for ATMOIC_LOAD and ATOMIC_STORE. // For now, atomics are considered to be volatile always. // FIXME: Volatile isn't really correct; we should keep track of atomic // orderings in the memoperand. - Flags |= MachineMemOperand::MOVolatile; + unsigned Flags = MachineMemOperand::MOVolatile; + if (Opcode != ISD::ATOMIC_STORE) + Flags |= MachineMemOperand::MOLoad; + if (Opcode != ISD::ATOMIC_LOAD) + Flags |= MachineMemOperand::MOStore; MachineMemOperand *MMO = MF.getMachineMemOperand(PtrInfo, Flags, MemVT.getStoreSize(), Alignment); @@ -3982,17 +3986,17 @@ SDValue SelectionDAG::getAtomic(unsigned Opcode, DebugLoc dl, EVT MemVT, Alignment = getEVTAlignment(MemVT); MachineFunction &MF = getMachineFunction(); - // A monotonic store does not load; a release store "loads" in the sense - // that other stores cannot be sunk past it. + // An atomic store does not load. An atomic load does not store. // (An atomicrmw obviously both loads and stores.) - unsigned Flags = MachineMemOperand::MOStore; - if (Opcode != ISD::ATOMIC_STORE || Ordering > Monotonic) - Flags |= MachineMemOperand::MOLoad; - - // For now, atomics are considered to be volatile always. + // For now, atomics are considered to be volatile always, and they are + // chained as such. // FIXME: Volatile isn't really correct; we should keep track of atomic // orderings in the memoperand. - Flags |= MachineMemOperand::MOVolatile; + unsigned Flags = MachineMemOperand::MOVolatile; + if (Opcode != ISD::ATOMIC_STORE) + Flags |= MachineMemOperand::MOLoad; + if (Opcode != ISD::ATOMIC_LOAD) + Flags |= MachineMemOperand::MOStore; MachineMemOperand *MMO = MF.getMachineMemOperand(MachinePointerInfo(PtrVal), Flags, @@ -4055,16 +4059,17 @@ SDValue SelectionDAG::getAtomic(unsigned Opcode, DebugLoc dl, EVT MemVT, Alignment = getEVTAlignment(MemVT); MachineFunction &MF = getMachineFunction(); - // A monotonic load does not store; an acquire load "stores" in the sense - // that other loads cannot be hoisted past it. - unsigned Flags = MachineMemOperand::MOLoad; - if (Ordering > Monotonic) - Flags |= MachineMemOperand::MOStore; - - // For now, atomics are considered to be volatile always. + // An atomic store does not load. An atomic load does not store. + // (An atomicrmw obviously both loads and stores.) + // For now, atomics are considered to be volatile always, and they are + // chained as such. // FIXME: Volatile isn't really correct; we should keep track of atomic // orderings in the memoperand. - Flags |= MachineMemOperand::MOVolatile; + unsigned Flags = MachineMemOperand::MOVolatile; + if (Opcode != ISD::ATOMIC_STORE) + Flags |= MachineMemOperand::MOLoad; + if (Opcode != ISD::ATOMIC_LOAD) + Flags |= MachineMemOperand::MOStore; MachineMemOperand *MMO = MF.getMachineMemOperand(MachinePointerInfo(PtrVal), Flags, |