R600/SI: Custom lower i64 sign_extend

llvm-svn: 183136

3 files changed, 31 insertions, 0 deletions

diff --git a/llvm/lib/Target/R600/SIISelLowering.cpp b/llvm/lib/Target/R600/SIISelLowering.cpp
index 8726bf346d1..825812f3796 100644
--- a/llvm/lib/Target/R600/SIISelLowering.cpp
+++ b/llvm/lib/Target/R600/SIISelLowering.cpp
@@ -74,6 +74,8 @@ SITargetLowering::SITargetLowering(TargetMachine &TM) :
 
   setOperationAction(ISD::SELECT_CC, MVT::Other, Expand);
 
+  setOperationAction(ISD::SIGN_EXTEND, MVT::i64, Custom);
+
   setTargetDAGCombine(ISD::SELECT_CC);
 
   setTargetDAGCombine(ISD::SETCC);
@@ -266,6 +268,7 @@ SDValue SITargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) const {
   default: return AMDGPUTargetLowering::LowerOperation(Op, DAG);
   case ISD::BRCOND: return LowerBRCOND(Op, DAG);
   case ISD::SELECT_CC: return LowerSELECT_CC(Op, DAG);
+  case ISD::SIGN_EXTEND: return LowerSIGN_EXTEND(Op, DAG);
   }
   return SDValue();
 }
@@ -383,6 +386,21 @@ SDValue SITargetLowering::LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const {
   return DAG.getNode(ISD::SELECT, DL, VT, Cond, True, False);
 }
 
+SDValue SITargetLowering::LowerSIGN_EXTEND(SDValue Op,
+                                           SelectionDAG &DAG) const {
+  EVT VT = Op.getValueType();
+  SDLoc DL(Op);
+
+  if (VT != MVT::i64) {
+    return SDValue();
+  }
+
+  SDValue Hi = DAG.getNode(ISD::SRA, DL, MVT::i32, Op.getOperand(0),
+                                                 DAG.getConstant(31, MVT::i32));
+
+  return DAG.getNode(ISD::BUILD_PAIR, DL, VT, Op.getOperand(0), Hi);
+}
+
 //===----------------------------------------------------------------------===//
 // Custom DAG optimizations
 //===----------------------------------------------------------------------===//
diff --git a/llvm/lib/Target/R600/SIISelLowering.h b/llvm/lib/Target/R600/SIISelLowering.h
index f37f0a573eb..5288a40f5b6 100644
--- a/llvm/lib/Target/R600/SIISelLowering.h
+++ b/llvm/lib/Target/R600/SIISelLowering.h
@@ -25,6 +25,7 @@ class SITargetLowering : public AMDGPUTargetLowering {
   const TargetRegisterInfo * TRI;
 
   SDValue LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const;
+  SDValue LowerSIGN_EXTEND(SDValue Op, SelectionDAG &DAG) const;
   SDValue LowerBRCOND(SDValue Op, SelectionDAG &DAG) const;
 
   bool foldImm(SDValue &Operand, int32_t &Immediate,
diff --git a/llvm/test/CodeGen/R600/sign_extend.ll b/llvm/test/CodeGen/R600/sign_extend.ll
new file mode 100644
index 00000000000..e4ef5344701
--- /dev/null
+++ b/llvm/test/CodeGen/R600/sign_extend.ll
@@ -0,0 +1,12 @@
+
+; RUN: llc < %s -march=r600 -mcpu=SI | FileCheck %s
+
+; CHECK: V_ASHR
+define void @test(i64 addrspace(1)* %out, i32 %a, i32 %b, i32 %c)  {
+entry:
+  %0 = mul i32 %a, %b
+  %1 = add i32 %0, %c
+  %2 = sext i32 %1 to i64
+  store i64 %2, i64 addrspace(1)* %out
+  ret void
+}