diff options
Diffstat (limited to 'lib/CodeGen')
| -rw-r--r-- | lib/CodeGen/SelectionDAG/SelectionDAG.cpp | 19 |
1 files changed, 17 insertions, 2 deletions
diff --git a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp index 5f5a880edf..19da986fe8 100644 --- a/lib/CodeGen/SelectionDAG/SelectionDAG.cpp +++ b/lib/CodeGen/SelectionDAG/SelectionDAG.cpp @@ -3840,6 +3840,8 @@ SDValue SelectionDAG::getAtomic(unsigned Opcode, DebugLoc dl, EVT MemVT, unsigned Flags = MachineMemOperand::MOLoad | MachineMemOperand::MOStore; // 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; MachineMemOperand *MMO = @@ -3889,9 +3891,16 @@ SDValue SelectionDAG::getAtomic(unsigned Opcode, DebugLoc dl, EVT MemVT, Alignment = getEVTAlignment(MemVT); MachineFunction &MF = getMachineFunction(); - unsigned Flags = MachineMemOperand::MOLoad | MachineMemOperand::MOStore; + // A monotonic store does not load; a release store "loads" in the sense + // that other stores cannot be sunk past it. + // (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. + // FIXME: Volatile isn't really correct; we should keep track of atomic + // orderings in the memoperand. Flags |= MachineMemOperand::MOVolatile; MachineMemOperand *MMO = @@ -3954,9 +3963,15 @@ SDValue SelectionDAG::getAtomic(unsigned Opcode, DebugLoc dl, EVT MemVT, Alignment = getEVTAlignment(MemVT); MachineFunction &MF = getMachineFunction(); - unsigned Flags = MachineMemOperand::MOLoad | MachineMemOperand::MOStore; + // 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. + // FIXME: Volatile isn't really correct; we should keep track of atomic + // orderings in the memoperand. Flags |= MachineMemOperand::MOVolatile; MachineMemOperand *MMO = |