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Diffstat (limited to 'contrib/llvm/lib/Target/ARM/ARMSelectionDAGInfo.cpp')
| -rw-r--r-- | contrib/llvm/lib/Target/ARM/ARMSelectionDAGInfo.cpp | 200 |
1 files changed, 200 insertions, 0 deletions
diff --git a/contrib/llvm/lib/Target/ARM/ARMSelectionDAGInfo.cpp b/contrib/llvm/lib/Target/ARM/ARMSelectionDAGInfo.cpp new file mode 100644 index 000000000000..93add6ee33cf --- /dev/null +++ b/contrib/llvm/lib/Target/ARM/ARMSelectionDAGInfo.cpp @@ -0,0 +1,200 @@ +//===-- ARMSelectionDAGInfo.cpp - ARM 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 ARMSelectionDAGInfo class. +// +//===----------------------------------------------------------------------===// + +#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>()) { +} + +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 { + // 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; + const unsigned MAX_LOADS_IN_LDM = 6; + SDValue TFOps[MAX_LOADS_IN_LDM]; + SDValue Loads[MAX_LOADS_IN_LDM]; + 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, &TFOps[0], 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, &TFOps[0], 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, &TFOps[0], 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, &TFOps[0], 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 { + // Use default for non AAPCS (or Darwin) subtargets + if (!Subtarget->isAAPCS_ABI() || Subtarget->isTargetDarwin()) + return SDValue(); + + const ARMTargetLowering &TLI = + *static_cast<const ARMTargetLowering*>(DAG.getTarget().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(Chain, + Type::getVoidTy(*DAG.getContext()), // return type + false, // return sign ext + false, // return zero ext + false, // is var arg + false, // is in regs + 0, // number of fixed arguments + TLI.getLibcallCallingConv(RTLIB::MEMSET), // call conv + false, // is tail call + false, // does not return + false, // is return val used + DAG.getExternalSymbol(TLI.getLibcallName(RTLIB::MEMSET), + TLI.getPointerTy()), // callee + Args, DAG, dl); + std::pair<SDValue,SDValue> CallResult = + TLI.LowerCallTo(CLI); + + return CallResult.second; +} |