1 files changed, 41 insertions, 7 deletions
diff --git a/lib/Target/AArch64/AArch64SelectionDAGInfo.cpp b/lib/Target/AArch64/AArch64SelectionDAGInfo.cpp
index 6bbe075..5c65b75 100644
--- a/lib/Target/AArch64/AArch64SelectionDAGInfo.cpp
+++ b/lib/Target/AArch64/AArch64SelectionDAGInfo.cpp
@@ -11,15 +11,49 @@
 //
 //===----------------------------------------------------------------------===//
 
-#define DEBUG_TYPE "arm-selectiondag-info"
 #include "AArch64TargetMachine.h"
-#include "llvm/CodeGen/SelectionDAG.h"
 using namespace llvm;
 
-AArch64SelectionDAGInfo::AArch64SelectionDAGInfo(const AArch64TargetMachine &TM)
-  : TargetSelectionDAGInfo(TM),
-    Subtarget(&TM.getSubtarget<AArch64Subtarget>()) {
-}
+#define DEBUG_TYPE "aarch64-selectiondag-info"
+
+AArch64SelectionDAGInfo::AArch64SelectionDAGInfo(const TargetMachine &TM)
+    : TargetSelectionDAGInfo(TM),
+      Subtarget(&TM.getSubtarget<AArch64Subtarget>()) {}
+
+AArch64SelectionDAGInfo::~AArch64SelectionDAGInfo() {}
+
+SDValue AArch64SelectionDAGInfo::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() : nullptr;
+  // For small size (< 256), it is not beneficial to use bzero
+  // instead of memset.
+  if (bzeroEntry && (!SizeValue || SizeValue->getZExtValue() > 256)) {
+    const AArch64TargetLowering &TLI =
+        *static_cast<const AArch64TargetLowering *>(
+            DAG.getTarget().getTargetLowering());
 
-AArch64SelectionDAGInfo::~AArch64SelectionDAGInfo() {
+    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(DAG);
+    CLI.setDebugLoc(dl).setChain(Chain)
+      .setCallee(CallingConv::C, Type::getVoidTy(*DAG.getContext()),
+                 DAG.getExternalSymbol(bzeroEntry, IntPtr), &Args, 0)
+      .setDiscardResult();
+    std::pair<SDValue, SDValue> CallResult = TLI.LowerCallTo(CLI);
+    return CallResult.second;
+  }
+  return SDValue();
 }