Thumb2SizeReduction: Check the correct set of registers for LDMIA.
[oota-llvm.git] / lib / Target / ARM / ARMSelectionDAGInfo.cpp
index aa1e398c0e42ee47d31614a29501bde52900deba..06bde40e037a459a9fdf2ebc2a2618cc06638e74 100644 (file)
 //
 //===----------------------------------------------------------------------===//
 
-#define DEBUG_TYPE "arm-selectiondag-info"
 #include "ARMTargetMachine.h"
+#include "llvm/CodeGen/SelectionDAG.h"
+#include "llvm/IR/DerivedTypes.h"
 using namespace llvm;
 
-ARMSelectionDAGInfo::ARMSelectionDAGInfo(const TargetMachine &TM)
-  : TargetSelectionDAGInfo(TM),
-    Subtarget(&TM.getSubtarget<ARMSubtarget>()) {
-}
+#define DEBUG_TYPE "arm-selectiondag-info"
+
+ARMSelectionDAGInfo::ARMSelectionDAGInfo(const DataLayout &DL)
+    : TargetSelectionDAGInfo(&DL) {}
 
 ARMSelectionDAGInfo::~ARMSelectionDAGInfo() {
 }
 
 SDValue
-ARMSelectionDAGInfo::EmitTargetCodeForMemcpy(SelectionDAG &DAG, DebugLoc dl,
+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.getMachineFunction().getSubtarget<ARMSubtarget>();
   // Do repeated 4-byte loads and stores. To be improved.
   // This requires 4-byte alignment.
   if ((Align & 3) != 0)
@@ -41,7 +44,7 @@ ARMSelectionDAGInfo::EmitTargetCodeForMemcpy(SelectionDAG &DAG, DebugLoc dl,
   if (!ConstantSize)
     return SDValue();
   uint64_t SizeVal = ConstantSize->getZExtValue();
-  if (!AlwaysInline && SizeVal > Subtarget->getMaxInlineSizeThreshold())
+  if (!AlwaysInline && SizeVal > Subtarget.getMaxInlineSizeThreshold())
     return SDValue();
 
   unsigned BytesLeft = SizeVal & 3;
@@ -50,9 +53,10 @@ ARMSelectionDAGInfo::EmitTargetCodeForMemcpy(SelectionDAG &DAG, DebugLoc dl,
   EVT VT = MVT::i32;
   unsigned VTSize = 4;
   unsigned i = 0;
-  const unsigned MAX_LOADS_IN_LDM = 6;
-  SDValue TFOps[MAX_LOADS_IN_LDM];
-  SDValue Loads[MAX_LOADS_IN_LDM];
+  // 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
@@ -63,24 +67,26 @@ ARMSelectionDAGInfo::EmitTargetCodeForMemcpy(SelectionDAG &DAG, DebugLoc dl,
          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)),
+                                         DAG.getConstant(SrcOff, dl, MVT::i32)),
                              SrcPtrInfo.getWithOffset(SrcOff), isVolatile,
-                             false, 0);
+                             false, false, 0);
       TFOps[i] = Loads[i].getValue(1);
       SrcOff += VTSize;
     }
-    Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, &TFOps[0], i);
+    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)),
+                                          DAG.getConstant(DstOff, dl, MVT::i32)),
                               DstPtrInfo.getWithOffset(DstOff),
                               isVolatile, false, 0);
       DstOff += VTSize;
     }
-    Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, &TFOps[0], i);
+    Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
+                        makeArrayRef(TFOps, i));
 
     EmittedNumMemOps += i;
   }
@@ -102,14 +108,16 @@ ARMSelectionDAGInfo::EmitTargetCodeForMemcpy(SelectionDAG &DAG, DebugLoc dl,
 
     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, 0);
+                                       DAG.getConstant(SrcOff, dl, 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, &TFOps[0], i);
+  Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
+                      makeArrayRef(TFOps, i));
 
   i = 0;
   BytesLeft = BytesLeftSave;
@@ -124,11 +132,69 @@ ARMSelectionDAGInfo::EmitTargetCodeForMemcpy(SelectionDAG &DAG, DebugLoc dl,
 
     TFOps[i] = DAG.getStore(Chain, dl, Loads[i],
                             DAG.getNode(ISD::ADD, dl, MVT::i32, Dst,
-                                        DAG.getConstant(DstOff, MVT::i32)),
+                                        DAG.getConstant(DstOff, dl, MVT::i32)),
                             DstPtrInfo.getWithOffset(DstOff), false, false, 0);
     ++i;
     DstOff += VTSize;
     BytesLeft -= VTSize;
   }
-  return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, &TFOps[0], i);
+  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.getMachineFunction().getSubtarget<ARMSubtarget>();
+  // Use default for non-AAPCS (or MachO) subtargets
+  if (!Subtarget.isAAPCS_ABI() || Subtarget.isTargetMachO() ||
+      Subtarget.isTargetWindows())
+    return SDValue();
+
+  const ARMTargetLowering &TLI = *Subtarget.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;
 }