1 files changed, 43 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Target/BPF/BPFSelectionDAGInfo.cpp b/contrib/llvm/lib/Target/BPF/BPFSelectionDAGInfo.cpp
new file mode 100644
index 000000000000..24d5f59bbfd7
--- /dev/null
+++ b/contrib/llvm/lib/Target/BPF/BPFSelectionDAGInfo.cpp
@@ -0,0 +1,43 @@
+//===-- BPFSelectionDAGInfo.cpp - BPF 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 BPFSelectionDAGInfo class.
+//
+//===----------------------------------------------------------------------===//
+
+#include "BPFTargetMachine.h"
+#include "llvm/CodeGen/SelectionDAG.h"
+#include "llvm/IR/DerivedTypes.h"
+using namespace llvm;
+
+#define DEBUG_TYPE "bpf-selectiondag-info"
+
+SDValue BPFSelectionDAGInfo::EmitTargetCodeForMemcpy(
+    SelectionDAG &DAG, const SDLoc &dl, SDValue Chain, SDValue Dst, SDValue Src,
+    SDValue Size, unsigned Align, bool isVolatile, bool AlwaysInline,
+    MachinePointerInfo DstPtrInfo, MachinePointerInfo SrcPtrInfo) const {
+  // Requires the copy size to be a constant.
+  ConstantSDNode *ConstantSize = dyn_cast<ConstantSDNode>(Size);
+  if (!ConstantSize)
+    return SDValue();
+
+  unsigned CopyLen = ConstantSize->getZExtValue();
+  unsigned StoresNumEstimate = alignTo(CopyLen, Align) >> Log2_32(Align);
+  // Impose the same copy length limit as MaxStoresPerMemcpy.
+  if (StoresNumEstimate > getCommonMaxStoresPerMemFunc())
+    return SDValue();
+
+  SDVTList VTs = DAG.getVTList(MVT::Other, MVT::Glue);
+
+  Dst = DAG.getNode(BPFISD::MEMCPY, dl, VTs, Chain, Dst, Src,
+                    DAG.getConstant(CopyLen, dl, MVT::i64),
+                    DAG.getConstant(Align, dl, MVT::i64));
+
+  return Dst.getValue(0);
+}