1 files changed, 57 insertions, 0 deletions
diff --git a/lib/Target/ARM64/ARM64SelectionDAGInfo.cpp b/lib/Target/ARM64/ARM64SelectionDAGInfo.cpp
new file mode 100644
index 0000000000..79d507f7da
--- /dev/null
+++ b/lib/Target/ARM64/ARM64SelectionDAGInfo.cpp
@@ -0,0 +1,57 @@
+//===-- ARM64SelectionDAGInfo.cpp - ARM64 SelectionDAG Info ---------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the ARM64SelectionDAGInfo class.
+//
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "arm64-selectiondag-info"
+#include "ARM64TargetMachine.h"
+using namespace llvm;
+
+ARM64SelectionDAGInfo::ARM64SelectionDAGInfo(const TargetMachine &TM)
+    : TargetSelectionDAGInfo(TM),
+      Subtarget(&TM.getSubtarget<ARM64Subtarget>()) {}
+
+ARM64SelectionDAGInfo::~ARM64SelectionDAGInfo() {}
+
+SDValue ARM64SelectionDAGInfo::EmitTargetCodeForMemset(
+    SelectionDAG &DAG, SDLoc dl, SDValue Chain, SDValue Dst, SDValue Src,
+    SDValue Size, unsigned Align, bool isVolatile,
+    MachinePointerInfo DstPtrInfo) const {
+  // Check to see if there is a specialized entry-point for memory zeroing.
+  ConstantSDNode *V = dyn_cast<ConstantSDNode>(Src);
+  ConstantSDNode *SizeValue = dyn_cast<ConstantSDNode>(Size);
+  const char *bzeroEntry =
+      (V && V->isNullValue()) ? Subtarget->getBZeroEntry() : 0;
+  // For small size (< 256), it is not beneficial to use bzero
+  // instead of memset.
+  if (bzeroEntry && (!SizeValue || SizeValue->getZExtValue() > 256)) {
+    const ARM64TargetLowering &TLI = *static_cast<const ARM64TargetLowering *>(
+                                          DAG.getTarget().getTargetLowering());
+
+    EVT IntPtr = TLI.getPointerTy();
+    Type *IntPtrTy = getDataLayout()->getIntPtrType(*DAG.getContext());
+    TargetLowering::ArgListTy Args;
+    TargetLowering::ArgListEntry Entry;
+    Entry.Node = Dst;
+    Entry.Ty = IntPtrTy;
+    Args.push_back(Entry);
+    Entry.Node = Size;
+    Args.push_back(Entry);
+    TargetLowering::CallLoweringInfo CLI(
+        Chain, Type::getVoidTy(*DAG.getContext()), false, false, false, false,
+        0, CallingConv::C, /*isTailCall=*/false,
+        /*doesNotRet=*/false, /*isReturnValueUsed=*/false,
+        DAG.getExternalSymbol(bzeroEntry, IntPtr), Args, DAG, dl);
+    std::pair<SDValue, SDValue> CallResult = TLI.LowerCallTo(CLI);
+    return CallResult.second;
+  }
+  return SDValue();
+}