- Make lowering of "add with overflow" customizable by back-ends.

- Mark "add with overflow" as having a custom lowering for X86. Give it a null
  lowering representation for now.

llvm-svn: 59971

2 files changed, 15 insertions, 0 deletions

diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index 9c5458d54ac..efe7bac72eb 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -780,6 +780,12 @@ X86TargetLowering::X86TargetLowering(X86TargetMachine &TM)
   // We want to custom lower some of our intrinsics.
   setOperationAction(ISD::INTRINSIC_WO_CHAIN, MVT::Other, Custom);
 
+  // Add with overflow operations are custom lowered.
+  setOperationAction(ISD::SADDO, MVT::i32, Custom);
+  setOperationAction(ISD::SADDO, MVT::i64, Custom);
+  setOperationAction(ISD::UADDO, MVT::i32, Custom);
+  setOperationAction(ISD::UADDO, MVT::i64, Custom);
+
   // We have target-specific dag combine patterns for the following nodes:
   setTargetDAGCombine(ISD::VECTOR_SHUFFLE);
   setTargetDAGCombine(ISD::BUILD_VECTOR);
@@ -6142,6 +6148,11 @@ SDValue X86TargetLowering::LowerCTTZ(SDValue Op, SelectionDAG &DAG) {
   return Op;
 }
 
+SDValue X86TargetLowering::LowerXADDO(SDValue Op, SelectionDAG &DAG,
+                                      ISD::NodeType NTy) {
+  return SDValue();
+}
+
 SDValue X86TargetLowering::LowerCMP_SWAP(SDValue Op, SelectionDAG &DAG) {
   MVT T = Op.getValueType();
   unsigned Reg = 0;
@@ -6321,6 +6332,8 @@ SDValue X86TargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) {
   case ISD::FLT_ROUNDS_:        return LowerFLT_ROUNDS_(Op, DAG);
   case ISD::CTLZ:               return LowerCTLZ(Op, DAG);
   case ISD::CTTZ:               return LowerCTTZ(Op, DAG);
+  case ISD::SADDO:              return LowerXADDO(Op, DAG, ISD::SADDO);
+  case ISD::UADDO:              return LowerXADDO(Op, DAG, ISD::UADDO);
       
   // FIXME: REMOVE THIS WHEN LegalizeDAGTypes lands.
   case ISD::READCYCLECOUNTER:
diff --git a/llvm/lib/Target/X86/X86ISelLowering.h b/llvm/lib/Target/X86/X86ISelLowering.h
index 2358889fda8..e9d8e55e106 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.h
+++ b/llvm/lib/Target/X86/X86ISelLowering.h
@@ -592,6 +592,8 @@ namespace llvm {
     SDValue LowerFLT_ROUNDS_(SDValue Op, SelectionDAG &DAG);
     SDValue LowerCTLZ(SDValue Op, SelectionDAG &DAG);
     SDValue LowerCTTZ(SDValue Op, SelectionDAG &DAG);
+    SDValue LowerXADDO(SDValue Op, SelectionDAG &DAG, ISD::NodeType NTy);
+
     SDValue LowerCMP_SWAP(SDValue Op, SelectionDAG &DAG);
     SDValue LowerLOAD_SUB(SDValue Op, SelectionDAG &DAG);
     SDValue LowerATOMIC_BINARY_64(SDValue Op, SelectionDAG &DAG,