From 2763dd085892384b4bd05e2e41859ddd138f5018 Mon Sep 17 00:00:00 2001
From: Tom Stellard <thomas.stellard@amd.com>
Date: Fri, 19 Jul 2013 12:29:02 -0700
Subject: [PATCH 3/3] R600/SI: Custom lower i64 ZERO_EXTEND

---
 lib/Target/R600/SIISelLowering.cpp | 15 +++++++++++++++
 lib/Target/R600/SIISelLowering.h   |  1 +
 test/CodeGen/R600/zero_extend.ll   | 18 ++++++++++++++++++
 3 files changed, 34 insertions(+)
 create mode 100644 test/CodeGen/R600/zero_extend.ll

diff --git a/lib/Target/R600/SIISelLowering.cpp b/lib/Target/R600/SIISelLowering.cpp
index 316567c..edb91e3 100644
--- a/lib/Target/R600/SIISelLowering.cpp
+++ b/lib/Target/R600/SIISelLowering.cpp
@@ -79,6 +79,7 @@ SITargetLowering::SITargetLowering(TargetMachine &TM) :
   setOperationAction(ISD::SETCC, MVT::v4i1, Expand);
 
   setOperationAction(ISD::SIGN_EXTEND, MVT::i64, Custom);
+  setOperationAction(ISD::ZERO_EXTEND, MVT::i64, Custom);
 
   setOperationAction(ISD::INTRINSIC_WO_CHAIN, MVT::Other, Custom);
 
@@ -346,6 +347,7 @@ SDValue SITargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) const {
   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);
+  case ISD::ZERO_EXTEND: return LowerZERO_EXTEND(Op, DAG);
   case ISD::GlobalAddress: return LowerGlobalAddress(MFI, Op, DAG);
   case ISD::INTRINSIC_WO_CHAIN: {
     unsigned IntrinsicID =
@@ -527,6 +529,19 @@ SDValue SITargetLowering::LowerSIGN_EXTEND(SDValue Op,
   return DAG.getNode(ISD::BUILD_PAIR, DL, VT, Op.getOperand(0), Hi);
 }
 
+SDValue SITargetLowering::LowerZERO_EXTEND(SDValue Op,
+                                           SelectionDAG &DAG) const {
+  EVT VT = Op.getValueType();
+  SDLoc DL(Op);
+
+  if (VT != MVT::i64) {
+    return SDValue();
+  }
+
+  return DAG.getNode(ISD::BUILD_PAIR, DL, VT, Op.getOperand(0),
+                                              DAG.getConstant(0, MVT::i32));
+}
+
 //===----------------------------------------------------------------------===//
 // Custom DAG optimizations
 //===----------------------------------------------------------------------===//
diff --git a/lib/Target/R600/SIISelLowering.h b/lib/Target/R600/SIISelLowering.h
index 0a856d5..08c1d17 100644
--- a/lib/Target/R600/SIISelLowering.h
+++ b/lib/Target/R600/SIISelLowering.h
@@ -25,6 +25,7 @@ class SITargetLowering : public AMDGPUTargetLowering {
                          SDValue Chain, unsigned Offset) const;
   SDValue LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const;
   SDValue LowerSIGN_EXTEND(SDValue Op, SelectionDAG &DAG) const;
+  SDValue LowerZERO_EXTEND(SDValue Op, SelectionDAG &DAG) const;
   SDValue LowerBRCOND(SDValue Op, SelectionDAG &DAG) const;
 
   bool foldImm(SDValue &Operand, int32_t &Immediate,
diff --git a/test/CodeGen/R600/zero_extend.ll b/test/CodeGen/R600/zero_extend.ll
new file mode 100644
index 0000000..413b849
--- /dev/null
+++ b/test/CodeGen/R600/zero_extend.ll
@@ -0,0 +1,18 @@
+; RUN: llc < %s -march=r600 -mcpu=redwood | FileCheck %s --check-prefix=R600-CHECK
+; RUN: llc < %s -march=r600 -mcpu=SI | FileCheck %s --check-prefix=SI-CHECK
+
+; R600-CHECK: @test
+; R600-CHECK: RAT_WRITE_CACHELESS_32_eg
+; R600-CHECK: RAT_WRITE_CACHELESS_32_eg
+
+; SI-CHECK: @test
+; SI-CHECK: V_MOV_B32_e32 [[ZERO:VGPR[0-9]]], 0
+; SI-CHECK: BUFFER_STORE_DWORDX2 VGPR0_[[ZERO]]
+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 = zext i32 %1 to i64
+  store i64 %2, i64 addrspace(1)* %out
+  ret void
+}
-- 
1.7.11.4