X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=lib%2FTarget%2FARM%2FARMSelectionDAGInfo.cpp;h=fa30ac31a30f79bb3ef01c83c1ea131fa6729052;hb=12af22e8cc217827cf4f118b0f5e4ebbda9925ae;hp=c04ee3829c1d5f7c3f08cb3b64330a90ea516553;hpb=53c5e42ab9c1a2cce7ad19bb0b4dffe33c9473e6;p=oota-llvm.git

diff --git a/lib/Target/ARM/ARMSelectionDAGInfo.cpp b/lib/Target/ARM/ARMSelectionDAGInfo.cpp
index c04ee3829c1..fa30ac31a30 100644
--- a/lib/Target/ARM/ARMSelectionDAGInfo.cpp
+++ b/lib/Target/ARM/ARMSelectionDAGInfo.cpp
@@ -11,12 +11,189 @@
 //
 //===----------------------------------------------------------------------===//
 
-#define DEBUG_TYPE "arm-selectiondag-info"
-#include "ARMSelectionDAGInfo.h"
+#include "ARMTargetMachine.h"
+#include "llvm/CodeGen/SelectionDAG.h"
+#include "llvm/IR/DerivedTypes.h"
 using namespace llvm;
 
-ARMSelectionDAGInfo::ARMSelectionDAGInfo() {
-}
+#define DEBUG_TYPE "arm-selectiondag-info"
+
+ARMSelectionDAGInfo::ARMSelectionDAGInfo(const DataLayout &DL)
+    : TargetSelectionDAGInfo(&DL) {}
 
 ARMSelectionDAGInfo::~ARMSelectionDAGInfo() {
 }
+
+SDValue
+ARMSelectionDAGInfo::EmitTargetCodeForMemcpy(SelectionDAG &DAG, SDLoc dl,
+                                             SDValue Chain,
+                                             SDValue Dst, SDValue Src,
+                                             SDValue Size, unsigned Align,
+                                             bool isVolatile, bool AlwaysInline,
+                                             MachinePointerInfo DstPtrInfo,
+                                          MachinePointerInfo SrcPtrInfo) const {
+  const ARMSubtarget &Subtarget = DAG.getTarget().getSubtarget<ARMSubtarget>();
+  // Do repeated 4-byte loads and stores. To be improved.
+  // This requires 4-byte alignment.
+  if ((Align & 3) != 0)
+    return SDValue();
+  // This requires the copy size to be a constant, preferably
+  // within a subtarget-specific limit.
+  ConstantSDNode *ConstantSize = dyn_cast<ConstantSDNode>(Size);
+  if (!ConstantSize)
+    return SDValue();
+  uint64_t SizeVal = ConstantSize->getZExtValue();
+  if (!AlwaysInline && SizeVal > Subtarget.getMaxInlineSizeThreshold())
+    return SDValue();
+
+  unsigned BytesLeft = SizeVal & 3;
+  unsigned NumMemOps = SizeVal >> 2;
+  unsigned EmittedNumMemOps = 0;
+  EVT VT = MVT::i32;
+  unsigned VTSize = 4;
+  unsigned i = 0;
+  // Emit a maximum of 4 loads in Thumb1 since we have fewer registers
+  const unsigned MAX_LOADS_IN_LDM = Subtarget.isThumb1Only() ? 4 : 6;
+  SDValue TFOps[6];
+  SDValue Loads[6];
+  uint64_t SrcOff = 0, DstOff = 0;
+
+  // Emit up to MAX_LOADS_IN_LDM loads, then a TokenFactor barrier, then the
+  // same number of stores.  The loads and stores will get combined into
+  // ldm/stm later on.
+  while (EmittedNumMemOps < NumMemOps) {
+    for (i = 0;
+         i < MAX_LOADS_IN_LDM && EmittedNumMemOps + i < NumMemOps; ++i) {
+      Loads[i] = DAG.getLoad(VT, dl, Chain,
+                             DAG.getNode(ISD::ADD, dl, MVT::i32, Src,
+                                         DAG.getConstant(SrcOff, MVT::i32)),
+                             SrcPtrInfo.getWithOffset(SrcOff), isVolatile,
+                             false, false, 0);
+      TFOps[i] = Loads[i].getValue(1);
+      SrcOff += VTSize;
+    }
+    Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
+                        makeArrayRef(TFOps, i));
+
+    for (i = 0;
+         i < MAX_LOADS_IN_LDM && EmittedNumMemOps + i < NumMemOps; ++i) {
+      TFOps[i] = DAG.getStore(Chain, dl, Loads[i],
+                              DAG.getNode(ISD::ADD, dl, MVT::i32, Dst,
+                                          DAG.getConstant(DstOff, MVT::i32)),
+                              DstPtrInfo.getWithOffset(DstOff),
+                              isVolatile, false, 0);
+      DstOff += VTSize;
+    }
+    Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
+                        makeArrayRef(TFOps, i));
+
+    EmittedNumMemOps += i;
+  }
+
+  if (BytesLeft == 0)
+    return Chain;
+
+  // Issue loads / stores for the trailing (1 - 3) bytes.
+  unsigned BytesLeftSave = BytesLeft;
+  i = 0;
+  while (BytesLeft) {
+    if (BytesLeft >= 2) {
+      VT = MVT::i16;
+      VTSize = 2;
+    } else {
+      VT = MVT::i8;
+      VTSize = 1;
+    }
+
+    Loads[i] = DAG.getLoad(VT, dl, Chain,
+                           DAG.getNode(ISD::ADD, dl, MVT::i32, Src,
+                                       DAG.getConstant(SrcOff, MVT::i32)),
+                           SrcPtrInfo.getWithOffset(SrcOff),
+                           false, false, false, 0);
+    TFOps[i] = Loads[i].getValue(1);
+    ++i;
+    SrcOff += VTSize;
+    BytesLeft -= VTSize;
+  }
+  Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
+                      makeArrayRef(TFOps, i));
+
+  i = 0;
+  BytesLeft = BytesLeftSave;
+  while (BytesLeft) {
+    if (BytesLeft >= 2) {
+      VT = MVT::i16;
+      VTSize = 2;
+    } else {
+      VT = MVT::i8;
+      VTSize = 1;
+    }
+
+    TFOps[i] = DAG.getStore(Chain, dl, Loads[i],
+                            DAG.getNode(ISD::ADD, dl, MVT::i32, Dst,
+                                        DAG.getConstant(DstOff, MVT::i32)),
+                            DstPtrInfo.getWithOffset(DstOff), false, false, 0);
+    ++i;
+    DstOff += VTSize;
+    BytesLeft -= VTSize;
+  }
+  return DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
+                     makeArrayRef(TFOps, i));
+}
+
+// Adjust parameters for memset, EABI uses format (ptr, size, value),
+// GNU library uses (ptr, value, size)
+// See RTABI section 4.3.4
+SDValue ARMSelectionDAGInfo::
+EmitTargetCodeForMemset(SelectionDAG &DAG, SDLoc dl,
+                        SDValue Chain, SDValue Dst,
+                        SDValue Src, SDValue Size,
+                        unsigned Align, bool isVolatile,
+                        MachinePointerInfo DstPtrInfo) const {
+  const ARMSubtarget &Subtarget = DAG.getTarget().getSubtarget<ARMSubtarget>();
+  // Use default for non-AAPCS (or MachO) subtargets
+  if (!Subtarget.isAAPCS_ABI() || Subtarget.isTargetMachO() ||
+      Subtarget.isTargetWindows())
+    return SDValue();
+
+  const ARMTargetLowering &TLI =
+      *DAG.getTarget().getSubtarget<ARMSubtarget>().getTargetLowering();
+  TargetLowering::ArgListTy Args;
+  TargetLowering::ArgListEntry Entry;
+
+  // First argument: data pointer
+  Type *IntPtrTy = TLI.getDataLayout()->getIntPtrType(*DAG.getContext());
+  Entry.Node = Dst;
+  Entry.Ty = IntPtrTy;
+  Args.push_back(Entry);
+
+  // Second argument: buffer size
+  Entry.Node = Size;
+  Entry.Ty = IntPtrTy;
+  Entry.isSExt = false;
+  Args.push_back(Entry);
+
+  // Extend or truncate the argument to be an i32 value for the call.
+  if (Src.getValueType().bitsGT(MVT::i32))
+    Src = DAG.getNode(ISD::TRUNCATE, dl, MVT::i32, Src);
+  else
+    Src = DAG.getNode(ISD::ZERO_EXTEND, dl, MVT::i32, Src);
+
+  // Third argument: value to fill
+  Entry.Node = Src;
+  Entry.Ty = Type::getInt32Ty(*DAG.getContext());
+  Entry.isSExt = true;
+  Args.push_back(Entry);
+
+  // Emit __eabi_memset call
+  TargetLowering::CallLoweringInfo CLI(DAG);
+  CLI.setDebugLoc(dl).setChain(Chain)
+    .setCallee(TLI.getLibcallCallingConv(RTLIB::MEMSET),
+               Type::getVoidTy(*DAG.getContext()),
+               DAG.getExternalSymbol(TLI.getLibcallName(RTLIB::MEMSET),
+                                     TLI.getPointerTy()), std::move(Args), 0)
+    .setDiscardResult();
+
+  std::pair<SDValue,SDValue> CallResult = TLI.LowerCallTo(CLI);
+  return CallResult.second;
+}