Add entries for Expanding atomic intrinsics to libcalls. Just a placeholder

for the moment. The implementation of the libcall will follow.

Currently, the llvm-gcc knows when the intrinsics can be correctly handled by
the back end and only generates them in those cases, issuing libcalls directly
otherwise. That's too much coupling. The intrinsics should always be
generated and the back end decide how to handle them, be it with a libcall,
inline code, or whatever. This patch is a step in that direction.

rdar://8097623

llvm-svn: 106227

1 files changed, 19 insertions, 0 deletions

diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
index 6ae766889a5..c4bbd02d623 100644
--- a/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/LegalizeDAG.cpp
@@ -2375,6 +2375,25 @@ void SelectionDAGLegalize::ExpandNode(SDNode *Node,
     Results.push_back(CallResult.second);
     break;
   }
+  // By default, atomic intrinsics are marked Legal and lowered. Targets
+  // which don't support them directly, however, may want libcalls, in which
+  // case they mark them Expand, and we get here.
+  // FIXME: Unimplemented for now. Add libcalls.
+  case ISD::ATOMIC_SWAP:
+  case ISD::ATOMIC_LOAD_ADD:
+  case ISD::ATOMIC_LOAD_SUB:
+  case ISD::ATOMIC_LOAD_AND:
+  case ISD::ATOMIC_LOAD_OR:
+  case ISD::ATOMIC_LOAD_XOR:
+  case ISD::ATOMIC_LOAD_NAND:
+  case ISD::ATOMIC_LOAD_MIN:
+  case ISD::ATOMIC_LOAD_MAX:
+  case ISD::ATOMIC_LOAD_UMIN:
+  case ISD::ATOMIC_LOAD_UMAX:
+  case ISD::ATOMIC_CMP_SWAP: {
+    assert (0 && "atomic intrinsic not lowered!");
+    Results.push_back(Node->getOperand(0));
+  }
   case ISD::DYNAMIC_STACKALLOC:
     ExpandDYNAMIC_STACKALLOC(Node, Results);
     break;