| //===- ARCISelLowering.cpp - ARC DAG Lowering Impl --------------*- C++ -*-===// |
| // |
| // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. |
| // See https://llvm.org/LICENSE.txt for license information. |
| // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception |
| // |
| //===----------------------------------------------------------------------===// |
| // |
| // This file implements the ARCTargetLowering class. |
| // |
| //===----------------------------------------------------------------------===// |
| |
| #include "ARCISelLowering.h" |
| #include "ARC.h" |
| #include "ARCMachineFunctionInfo.h" |
| #include "ARCSubtarget.h" |
| #include "ARCTargetMachine.h" |
| #include "MCTargetDesc/ARCInfo.h" |
| #include "llvm/CodeGen/CallingConvLower.h" |
| #include "llvm/CodeGen/MachineFrameInfo.h" |
| #include "llvm/CodeGen/MachineFunction.h" |
| #include "llvm/CodeGen/MachineInstrBuilder.h" |
| #include "llvm/CodeGen/MachineJumpTableInfo.h" |
| #include "llvm/CodeGen/MachineRegisterInfo.h" |
| #include "llvm/CodeGen/SelectionDAGISel.h" |
| #include "llvm/CodeGen/ValueTypes.h" |
| #include "llvm/IR/CallingConv.h" |
| #include "llvm/IR/Intrinsics.h" |
| #include "llvm/Support/Debug.h" |
| #include <algorithm> |
| |
| #define DEBUG_TYPE "arc-lower" |
| |
| using namespace llvm; |
| |
| static SDValue lowerCallResult(SDValue Chain, SDValue InFlag, |
| const SmallVectorImpl<CCValAssign> &RVLocs, |
| SDLoc dl, SelectionDAG &DAG, |
| SmallVectorImpl<SDValue> &InVals); |
| |
| static ARCCC::CondCode ISDCCtoARCCC(ISD::CondCode isdCC) { |
| switch (isdCC) { |
| case ISD::SETUEQ: |
| return ARCCC::EQ; |
| case ISD::SETUGT: |
| return ARCCC::HI; |
| case ISD::SETUGE: |
| return ARCCC::HS; |
| case ISD::SETULT: |
| return ARCCC::LO; |
| case ISD::SETULE: |
| return ARCCC::LS; |
| case ISD::SETUNE: |
| return ARCCC::NE; |
| case ISD::SETEQ: |
| return ARCCC::EQ; |
| case ISD::SETGT: |
| return ARCCC::GT; |
| case ISD::SETGE: |
| return ARCCC::GE; |
| case ISD::SETLT: |
| return ARCCC::LT; |
| case ISD::SETLE: |
| return ARCCC::LE; |
| case ISD::SETNE: |
| return ARCCC::NE; |
| default: |
| llvm_unreachable("Unhandled ISDCC code."); |
| } |
| } |
| |
| ARCTargetLowering::ARCTargetLowering(const TargetMachine &TM, |
| const ARCSubtarget &Subtarget) |
| : TargetLowering(TM), Subtarget(Subtarget) { |
| // Set up the register classes. |
| addRegisterClass(MVT::i32, &ARC::GPR32RegClass); |
| |
| // Compute derived properties from the register classes |
| computeRegisterProperties(Subtarget.getRegisterInfo()); |
| |
| setStackPointerRegisterToSaveRestore(ARC::SP); |
| |
| setSchedulingPreference(Sched::Source); |
| |
| // Use i32 for setcc operations results (slt, sgt, ...). |
| setBooleanContents(ZeroOrOneBooleanContent); |
| setBooleanVectorContents(ZeroOrOneBooleanContent); |
| |
| for (unsigned Opc = 0; Opc < ISD::BUILTIN_OP_END; ++Opc) |
| setOperationAction(Opc, MVT::i32, Expand); |
| |
| // Operations to get us off of the ground. |
| // Basic. |
| setOperationAction(ISD::ADD, MVT::i32, Legal); |
| setOperationAction(ISD::SUB, MVT::i32, Legal); |
| setOperationAction(ISD::AND, MVT::i32, Legal); |
| setOperationAction(ISD::SMAX, MVT::i32, Legal); |
| setOperationAction(ISD::SMIN, MVT::i32, Legal); |
| |
| // Need barrel shifter. |
| setOperationAction(ISD::SHL, MVT::i32, Legal); |
| setOperationAction(ISD::SRA, MVT::i32, Legal); |
| setOperationAction(ISD::SRL, MVT::i32, Legal); |
| setOperationAction(ISD::ROTR, MVT::i32, Legal); |
| |
| setOperationAction(ISD::Constant, MVT::i32, Legal); |
| setOperationAction(ISD::UNDEF, MVT::i32, Legal); |
| |
| // Need multiplier |
| setOperationAction(ISD::MUL, MVT::i32, Legal); |
| setOperationAction(ISD::MULHS, MVT::i32, Legal); |
| setOperationAction(ISD::MULHU, MVT::i32, Legal); |
| setOperationAction(ISD::LOAD, MVT::i32, Legal); |
| setOperationAction(ISD::STORE, MVT::i32, Legal); |
| |
| setOperationAction(ISD::SELECT_CC, MVT::i32, Custom); |
| setOperationAction(ISD::BR_CC, MVT::i32, Custom); |
| setOperationAction(ISD::BRCOND, MVT::Other, Expand); |
| setOperationAction(ISD::BR_JT, MVT::Other, Expand); |
| setOperationAction(ISD::JumpTable, MVT::i32, Custom); |
| |
| // Have pseudo instruction for frame addresses. |
| setOperationAction(ISD::FRAMEADDR, MVT::i32, Legal); |
| // Custom lower global addresses. |
| setOperationAction(ISD::GlobalAddress, MVT::i32, Custom); |
| |
| // Expand var-args ops. |
| setOperationAction(ISD::VASTART, MVT::Other, Custom); |
| setOperationAction(ISD::VAEND, MVT::Other, Expand); |
| setOperationAction(ISD::VAARG, MVT::Other, Expand); |
| setOperationAction(ISD::VACOPY, MVT::Other, Expand); |
| |
| // Other expansions |
| setOperationAction(ISD::STACKSAVE, MVT::Other, Expand); |
| setOperationAction(ISD::STACKRESTORE, MVT::Other, Expand); |
| |
| // Sign extend inreg |
| setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1, Custom); |
| } |
| |
| const char *ARCTargetLowering::getTargetNodeName(unsigned Opcode) const { |
| switch (Opcode) { |
| case ARCISD::BL: |
| return "ARCISD::BL"; |
| case ARCISD::CMOV: |
| return "ARCISD::CMOV"; |
| case ARCISD::CMP: |
| return "ARCISD::CMP"; |
| case ARCISD::BRcc: |
| return "ARCISD::BRcc"; |
| case ARCISD::RET: |
| return "ARCISD::RET"; |
| case ARCISD::GAWRAPPER: |
| return "ARCISD::GAWRAPPER"; |
| } |
| return nullptr; |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Misc Lower Operation implementation |
| //===----------------------------------------------------------------------===// |
| |
| SDValue ARCTargetLowering::LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const { |
| SDValue LHS = Op.getOperand(0); |
| SDValue RHS = Op.getOperand(1); |
| ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(4))->get(); |
| SDValue TVal = Op.getOperand(2); |
| SDValue FVal = Op.getOperand(3); |
| SDLoc dl(Op); |
| ARCCC::CondCode ArcCC = ISDCCtoARCCC(CC); |
| assert(LHS.getValueType() == MVT::i32 && "Only know how to SELECT_CC i32"); |
| SDValue Cmp = DAG.getNode(ARCISD::CMP, dl, MVT::Glue, LHS, RHS); |
| return DAG.getNode(ARCISD::CMOV, dl, TVal.getValueType(), TVal, FVal, |
| DAG.getConstant(ArcCC, dl, MVT::i32), Cmp); |
| } |
| |
| SDValue ARCTargetLowering::LowerSIGN_EXTEND_INREG(SDValue Op, |
| SelectionDAG &DAG) const { |
| SDValue Op0 = Op.getOperand(0); |
| SDLoc dl(Op); |
| assert(Op.getValueType() == MVT::i32 && |
| "Unhandled target sign_extend_inreg."); |
| // These are legal |
| unsigned Width = cast<VTSDNode>(Op.getOperand(1))->getVT().getSizeInBits(); |
| if (Width == 16 || Width == 8) |
| return Op; |
| if (Width >= 32) { |
| return {}; |
| } |
| SDValue LS = DAG.getNode(ISD::SHL, dl, MVT::i32, Op0, |
| DAG.getConstant(32 - Width, dl, MVT::i32)); |
| SDValue SR = DAG.getNode(ISD::SRA, dl, MVT::i32, LS, |
| DAG.getConstant(32 - Width, dl, MVT::i32)); |
| return SR; |
| } |
| |
| SDValue ARCTargetLowering::LowerBR_CC(SDValue Op, SelectionDAG &DAG) const { |
| SDValue Chain = Op.getOperand(0); |
| ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(1))->get(); |
| SDValue LHS = Op.getOperand(2); |
| SDValue RHS = Op.getOperand(3); |
| SDValue Dest = Op.getOperand(4); |
| SDLoc dl(Op); |
| ARCCC::CondCode arcCC = ISDCCtoARCCC(CC); |
| assert(LHS.getValueType() == MVT::i32 && "Only know how to BR_CC i32"); |
| return DAG.getNode(ARCISD::BRcc, dl, MVT::Other, Chain, Dest, LHS, RHS, |
| DAG.getConstant(arcCC, dl, MVT::i32)); |
| } |
| |
| SDValue ARCTargetLowering::LowerJumpTable(SDValue Op, SelectionDAG &DAG) const { |
| auto *N = cast<JumpTableSDNode>(Op); |
| SDValue GA = DAG.getTargetJumpTable(N->getIndex(), MVT::i32); |
| return DAG.getNode(ARCISD::GAWRAPPER, SDLoc(N), MVT::i32, GA); |
| } |
| |
| #include "ARCGenCallingConv.inc" |
| |
| //===----------------------------------------------------------------------===// |
| // Call Calling Convention Implementation |
| //===----------------------------------------------------------------------===// |
| |
| /// ARC call implementation |
| SDValue ARCTargetLowering::LowerCall(TargetLowering::CallLoweringInfo &CLI, |
| SmallVectorImpl<SDValue> &InVals) const { |
| SelectionDAG &DAG = CLI.DAG; |
| SDLoc &dl = CLI.DL; |
| SmallVectorImpl<ISD::OutputArg> &Outs = CLI.Outs; |
| SmallVectorImpl<SDValue> &OutVals = CLI.OutVals; |
| SmallVectorImpl<ISD::InputArg> &Ins = CLI.Ins; |
| SDValue Chain = CLI.Chain; |
| SDValue Callee = CLI.Callee; |
| CallingConv::ID CallConv = CLI.CallConv; |
| bool IsVarArg = CLI.IsVarArg; |
| bool &IsTailCall = CLI.IsTailCall; |
| |
| IsTailCall = false; // Do not support tail calls yet. |
| |
| SmallVector<CCValAssign, 16> ArgLocs; |
| CCState CCInfo(CallConv, IsVarArg, DAG.getMachineFunction(), ArgLocs, |
| *DAG.getContext()); |
| |
| CCInfo.AnalyzeCallOperands(Outs, CC_ARC); |
| |
| SmallVector<CCValAssign, 16> RVLocs; |
| // Analyze return values to determine the number of bytes of stack required. |
| CCState RetCCInfo(CallConv, IsVarArg, DAG.getMachineFunction(), RVLocs, |
| *DAG.getContext()); |
| RetCCInfo.AllocateStack(CCInfo.getNextStackOffset(), 4); |
| RetCCInfo.AnalyzeCallResult(Ins, RetCC_ARC); |
| |
| // Get a count of how many bytes are to be pushed on the stack. |
| unsigned NumBytes = RetCCInfo.getNextStackOffset(); |
| auto PtrVT = getPointerTy(DAG.getDataLayout()); |
| |
| Chain = DAG.getCALLSEQ_START(Chain, NumBytes, 0, dl); |
| |
| SmallVector<std::pair<unsigned, SDValue>, 4> RegsToPass; |
| SmallVector<SDValue, 12> MemOpChains; |
| |
| SDValue StackPtr; |
| // Walk the register/memloc assignments, inserting copies/loads. |
| for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) { |
| CCValAssign &VA = ArgLocs[i]; |
| SDValue Arg = OutVals[i]; |
| |
| // Promote the value if needed. |
| switch (VA.getLocInfo()) { |
| default: |
| llvm_unreachable("Unknown loc info!"); |
| case CCValAssign::Full: |
| break; |
| case CCValAssign::SExt: |
| Arg = DAG.getNode(ISD::SIGN_EXTEND, dl, VA.getLocVT(), Arg); |
| break; |
| case CCValAssign::ZExt: |
| Arg = DAG.getNode(ISD::ZERO_EXTEND, dl, VA.getLocVT(), Arg); |
| break; |
| case CCValAssign::AExt: |
| Arg = DAG.getNode(ISD::ANY_EXTEND, dl, VA.getLocVT(), Arg); |
| break; |
| } |
| |
| // Arguments that can be passed on register must be kept at |
| // RegsToPass vector |
| if (VA.isRegLoc()) { |
| RegsToPass.push_back(std::make_pair(VA.getLocReg(), Arg)); |
| } else { |
| assert(VA.isMemLoc() && "Must be register or memory argument."); |
| if (!StackPtr.getNode()) |
| StackPtr = DAG.getCopyFromReg(Chain, dl, ARC::SP, |
| getPointerTy(DAG.getDataLayout())); |
| // Calculate the stack position. |
| SDValue SOffset = DAG.getIntPtrConstant(VA.getLocMemOffset(), dl); |
| SDValue PtrOff = DAG.getNode( |
| ISD::ADD, dl, getPointerTy(DAG.getDataLayout()), StackPtr, SOffset); |
| |
| SDValue Store = |
| DAG.getStore(Chain, dl, Arg, PtrOff, MachinePointerInfo()); |
| MemOpChains.push_back(Store); |
| IsTailCall = false; |
| } |
| } |
| |
| // Transform all store nodes into one single node because |
| // all store nodes are independent of each other. |
| if (!MemOpChains.empty()) |
| Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, MemOpChains); |
| |
| // Build a sequence of copy-to-reg nodes chained together with token |
| // chain and flag operands which copy the outgoing args into registers. |
| // The InFlag in necessary since all emitted instructions must be |
| // stuck together. |
| SDValue Glue; |
| for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i) { |
| Chain = DAG.getCopyToReg(Chain, dl, RegsToPass[i].first, |
| RegsToPass[i].second, Glue); |
| Glue = Chain.getValue(1); |
| } |
| |
| // If the callee is a GlobalAddress node (quite common, every direct call is) |
| // turn it into a TargetGlobalAddress node so that legalize doesn't hack it. |
| // Likewise ExternalSymbol -> TargetExternalSymbol. |
| bool IsDirect = true; |
| if (auto *G = dyn_cast<GlobalAddressSDNode>(Callee)) |
| Callee = DAG.getTargetGlobalAddress(G->getGlobal(), dl, MVT::i32); |
| else if (auto *E = dyn_cast<ExternalSymbolSDNode>(Callee)) |
| Callee = DAG.getTargetExternalSymbol(E->getSymbol(), MVT::i32); |
| else |
| IsDirect = false; |
| // Branch + Link = #chain, #target_address, #opt_in_flags... |
| // = Chain, Callee, Reg#1, Reg#2, ... |
| // |
| // Returns a chain & a flag for retval copy to use. |
| SDVTList NodeTys = DAG.getVTList(MVT::Other, MVT::Glue); |
| SmallVector<SDValue, 8> Ops; |
| Ops.push_back(Chain); |
| Ops.push_back(Callee); |
| |
| for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i) |
| Ops.push_back(DAG.getRegister(RegsToPass[i].first, |
| RegsToPass[i].second.getValueType())); |
| |
| // Add a register mask operand representing the call-preserved registers. |
| const TargetRegisterInfo *TRI = Subtarget.getRegisterInfo(); |
| const uint32_t *Mask = |
| TRI->getCallPreservedMask(DAG.getMachineFunction(), CallConv); |
| assert(Mask && "Missing call preserved mask for calling convention"); |
| Ops.push_back(DAG.getRegisterMask(Mask)); |
| |
| if (Glue.getNode()) |
| Ops.push_back(Glue); |
| |
| Chain = DAG.getNode(IsDirect ? ARCISD::BL : ARCISD::JL, dl, NodeTys, Ops); |
| Glue = Chain.getValue(1); |
| |
| // Create the CALLSEQ_END node. |
| Chain = DAG.getCALLSEQ_END(Chain, DAG.getConstant(NumBytes, dl, PtrVT, true), |
| DAG.getConstant(0, dl, PtrVT, true), Glue, dl); |
| Glue = Chain.getValue(1); |
| |
| // Handle result values, copying them out of physregs into vregs that we |
| // return. |
| if (IsTailCall) |
| return Chain; |
| return lowerCallResult(Chain, Glue, RVLocs, dl, DAG, InVals); |
| } |
| |
| /// Lower the result values of a call into the appropriate copies out of |
| /// physical registers / memory locations. |
| static SDValue lowerCallResult(SDValue Chain, SDValue Glue, |
| const SmallVectorImpl<CCValAssign> &RVLocs, |
| SDLoc dl, SelectionDAG &DAG, |
| SmallVectorImpl<SDValue> &InVals) { |
| SmallVector<std::pair<int, unsigned>, 4> ResultMemLocs; |
| // Copy results out of physical registers. |
| for (unsigned i = 0, e = RVLocs.size(); i != e; ++i) { |
| const CCValAssign &VA = RVLocs[i]; |
| if (VA.isRegLoc()) { |
| SDValue RetValue; |
| RetValue = |
| DAG.getCopyFromReg(Chain, dl, VA.getLocReg(), VA.getValVT(), Glue); |
| Chain = RetValue.getValue(1); |
| Glue = RetValue.getValue(2); |
| InVals.push_back(RetValue); |
| } else { |
| assert(VA.isMemLoc() && "Must be memory location."); |
| ResultMemLocs.push_back( |
| std::make_pair(VA.getLocMemOffset(), InVals.size())); |
| |
| // Reserve space for this result. |
| InVals.push_back(SDValue()); |
| } |
| } |
| |
| // Copy results out of memory. |
| SmallVector<SDValue, 4> MemOpChains; |
| for (unsigned i = 0, e = ResultMemLocs.size(); i != e; ++i) { |
| int Offset = ResultMemLocs[i].first; |
| unsigned Index = ResultMemLocs[i].second; |
| SDValue StackPtr = DAG.getRegister(ARC::SP, MVT::i32); |
| SDValue SpLoc = DAG.getNode(ISD::ADD, dl, MVT::i32, StackPtr, |
| DAG.getConstant(Offset, dl, MVT::i32)); |
| SDValue Load = |
| DAG.getLoad(MVT::i32, dl, Chain, SpLoc, MachinePointerInfo()); |
| InVals[Index] = Load; |
| MemOpChains.push_back(Load.getValue(1)); |
| } |
| |
| // Transform all loads nodes into one single node because |
| // all load nodes are independent of each other. |
| if (!MemOpChains.empty()) |
| Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, MemOpChains); |
| |
| return Chain; |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Formal Arguments Calling Convention Implementation |
| //===----------------------------------------------------------------------===// |
| |
| namespace { |
| |
| struct ArgDataPair { |
| SDValue SDV; |
| ISD::ArgFlagsTy Flags; |
| }; |
| |
| } // end anonymous namespace |
| |
| /// ARC formal arguments implementation |
| SDValue ARCTargetLowering::LowerFormalArguments( |
| SDValue Chain, CallingConv::ID CallConv, bool IsVarArg, |
| const SmallVectorImpl<ISD::InputArg> &Ins, const SDLoc &dl, |
| SelectionDAG &DAG, SmallVectorImpl<SDValue> &InVals) const { |
| switch (CallConv) { |
| default: |
| llvm_unreachable("Unsupported calling convention"); |
| case CallingConv::C: |
| case CallingConv::Fast: |
| return LowerCallArguments(Chain, CallConv, IsVarArg, Ins, dl, DAG, InVals); |
| } |
| } |
| |
| /// Transform physical registers into virtual registers, and generate load |
| /// operations for argument places on the stack. |
| SDValue ARCTargetLowering::LowerCallArguments( |
| SDValue Chain, CallingConv::ID CallConv, bool IsVarArg, |
| const SmallVectorImpl<ISD::InputArg> &Ins, SDLoc dl, SelectionDAG &DAG, |
| SmallVectorImpl<SDValue> &InVals) const { |
| MachineFunction &MF = DAG.getMachineFunction(); |
| MachineFrameInfo &MFI = MF.getFrameInfo(); |
| MachineRegisterInfo &RegInfo = MF.getRegInfo(); |
| auto *AFI = MF.getInfo<ARCFunctionInfo>(); |
| |
| // Assign locations to all of the incoming arguments. |
| SmallVector<CCValAssign, 16> ArgLocs; |
| CCState CCInfo(CallConv, IsVarArg, DAG.getMachineFunction(), ArgLocs, |
| *DAG.getContext()); |
| |
| CCInfo.AnalyzeFormalArguments(Ins, CC_ARC); |
| |
| unsigned StackSlotSize = 4; |
| |
| if (!IsVarArg) |
| AFI->setReturnStackOffset(CCInfo.getNextStackOffset()); |
| |
| // All getCopyFromReg ops must precede any getMemcpys to prevent the |
| // scheduler clobbering a register before it has been copied. |
| // The stages are: |
| // 1. CopyFromReg (and load) arg & vararg registers. |
| // 2. Chain CopyFromReg nodes into a TokenFactor. |
| // 3. Memcpy 'byVal' args & push final InVals. |
| // 4. Chain mem ops nodes into a TokenFactor. |
| SmallVector<SDValue, 4> CFRegNode; |
| SmallVector<ArgDataPair, 4> ArgData; |
| SmallVector<SDValue, 4> MemOps; |
| |
| // 1a. CopyFromReg (and load) arg registers. |
| for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) { |
| CCValAssign &VA = ArgLocs[i]; |
| SDValue ArgIn; |
| |
| if (VA.isRegLoc()) { |
| // Arguments passed in registers |
| EVT RegVT = VA.getLocVT(); |
| switch (RegVT.getSimpleVT().SimpleTy) { |
| default: { |
| LLVM_DEBUG(errs() << "LowerFormalArguments Unhandled argument type: " |
| << (unsigned)RegVT.getSimpleVT().SimpleTy << "\n"); |
| llvm_unreachable("Unhandled LowerFormalArguments type."); |
| } |
| case MVT::i32: |
| unsigned VReg = RegInfo.createVirtualRegister(&ARC::GPR32RegClass); |
| RegInfo.addLiveIn(VA.getLocReg(), VReg); |
| ArgIn = DAG.getCopyFromReg(Chain, dl, VReg, RegVT); |
| CFRegNode.push_back(ArgIn.getValue(ArgIn->getNumValues() - 1)); |
| } |
| } else { |
| // sanity check |
| assert(VA.isMemLoc()); |
| // Load the argument to a virtual register |
| unsigned ObjSize = VA.getLocVT().getStoreSize(); |
| assert((ObjSize <= StackSlotSize) && "Unhandled argument"); |
| |
| // Create the frame index object for this incoming parameter... |
| int FI = MFI.CreateFixedObject(ObjSize, VA.getLocMemOffset(), true); |
| |
| // Create the SelectionDAG nodes corresponding to a load |
| // from this parameter |
| SDValue FIN = DAG.getFrameIndex(FI, MVT::i32); |
| ArgIn = DAG.getLoad(VA.getLocVT(), dl, Chain, FIN, |
| MachinePointerInfo::getFixedStack(MF, FI)); |
| } |
| const ArgDataPair ADP = {ArgIn, Ins[i].Flags}; |
| ArgData.push_back(ADP); |
| } |
| |
| // 1b. CopyFromReg vararg registers. |
| if (IsVarArg) { |
| // Argument registers |
| static const MCPhysReg ArgRegs[] = {ARC::R0, ARC::R1, ARC::R2, ARC::R3, |
| ARC::R4, ARC::R5, ARC::R6, ARC::R7}; |
| auto *AFI = MF.getInfo<ARCFunctionInfo>(); |
| unsigned FirstVAReg = CCInfo.getFirstUnallocated(ArgRegs); |
| if (FirstVAReg < array_lengthof(ArgRegs)) { |
| int Offset = 0; |
| // Save remaining registers, storing higher register numbers at a higher |
| // address |
| // There are (array_lengthof(ArgRegs) - FirstVAReg) registers which |
| // need to be saved. |
| int VarFI = |
| MFI.CreateFixedObject((array_lengthof(ArgRegs) - FirstVAReg) * 4, |
| CCInfo.getNextStackOffset(), true); |
| AFI->setVarArgsFrameIndex(VarFI); |
| SDValue FIN = DAG.getFrameIndex(VarFI, MVT::i32); |
| for (unsigned i = FirstVAReg; i < array_lengthof(ArgRegs); i++) { |
| // Move argument from phys reg -> virt reg |
| unsigned VReg = RegInfo.createVirtualRegister(&ARC::GPR32RegClass); |
| RegInfo.addLiveIn(ArgRegs[i], VReg); |
| SDValue Val = DAG.getCopyFromReg(Chain, dl, VReg, MVT::i32); |
| CFRegNode.push_back(Val.getValue(Val->getNumValues() - 1)); |
| SDValue VAObj = DAG.getNode(ISD::ADD, dl, MVT::i32, FIN, |
| DAG.getConstant(Offset, dl, MVT::i32)); |
| // Move argument from virt reg -> stack |
| SDValue Store = |
| DAG.getStore(Val.getValue(1), dl, Val, VAObj, MachinePointerInfo()); |
| MemOps.push_back(Store); |
| Offset += 4; |
| } |
| } else { |
| llvm_unreachable("Too many var args parameters."); |
| } |
| } |
| |
| // 2. Chain CopyFromReg nodes into a TokenFactor. |
| if (!CFRegNode.empty()) |
| Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, CFRegNode); |
| |
| // 3. Memcpy 'byVal' args & push final InVals. |
| // Aggregates passed "byVal" need to be copied by the callee. |
| // The callee will use a pointer to this copy, rather than the original |
| // pointer. |
| for (const auto &ArgDI : ArgData) { |
| if (ArgDI.Flags.isByVal() && ArgDI.Flags.getByValSize()) { |
| unsigned Size = ArgDI.Flags.getByValSize(); |
| unsigned Align = std::max(StackSlotSize, ArgDI.Flags.getByValAlign()); |
| // Create a new object on the stack and copy the pointee into it. |
| int FI = MFI.CreateStackObject(Size, Align, false); |
| SDValue FIN = DAG.getFrameIndex(FI, MVT::i32); |
| InVals.push_back(FIN); |
| MemOps.push_back(DAG.getMemcpy( |
| Chain, dl, FIN, ArgDI.SDV, DAG.getConstant(Size, dl, MVT::i32), Align, |
| false, false, false, MachinePointerInfo(), MachinePointerInfo())); |
| } else { |
| InVals.push_back(ArgDI.SDV); |
| } |
| } |
| |
| // 4. Chain mem ops nodes into a TokenFactor. |
| if (!MemOps.empty()) { |
| MemOps.push_back(Chain); |
| Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, MemOps); |
| } |
| |
| return Chain; |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Return Value Calling Convention Implementation |
| //===----------------------------------------------------------------------===// |
| |
| bool ARCTargetLowering::CanLowerReturn( |
| CallingConv::ID CallConv, MachineFunction &MF, bool IsVarArg, |
| const SmallVectorImpl<ISD::OutputArg> &Outs, LLVMContext &Context) const { |
| SmallVector<CCValAssign, 16> RVLocs; |
| CCState CCInfo(CallConv, IsVarArg, MF, RVLocs, Context); |
| if (!CCInfo.CheckReturn(Outs, RetCC_ARC)) |
| return false; |
| if (CCInfo.getNextStackOffset() != 0 && IsVarArg) |
| return false; |
| return true; |
| } |
| |
| SDValue |
| ARCTargetLowering::LowerReturn(SDValue Chain, CallingConv::ID CallConv, |
| bool IsVarArg, |
| const SmallVectorImpl<ISD::OutputArg> &Outs, |
| const SmallVectorImpl<SDValue> &OutVals, |
| const SDLoc &dl, SelectionDAG &DAG) const { |
| auto *AFI = DAG.getMachineFunction().getInfo<ARCFunctionInfo>(); |
| MachineFrameInfo &MFI = DAG.getMachineFunction().getFrameInfo(); |
| |
| // CCValAssign - represent the assignment of |
| // the return value to a location |
| SmallVector<CCValAssign, 16> RVLocs; |
| |
| // CCState - Info about the registers and stack slot. |
| CCState CCInfo(CallConv, IsVarArg, DAG.getMachineFunction(), RVLocs, |
| *DAG.getContext()); |
| |
| // Analyze return values. |
| if (!IsVarArg) |
| CCInfo.AllocateStack(AFI->getReturnStackOffset(), 4); |
| |
| CCInfo.AnalyzeReturn(Outs, RetCC_ARC); |
| |
| SDValue Flag; |
| SmallVector<SDValue, 4> RetOps(1, Chain); |
| SmallVector<SDValue, 4> MemOpChains; |
| // Handle return values that must be copied to memory. |
| for (unsigned i = 0, e = RVLocs.size(); i != e; ++i) { |
| CCValAssign &VA = RVLocs[i]; |
| if (VA.isRegLoc()) |
| continue; |
| assert(VA.isMemLoc()); |
| if (IsVarArg) { |
| report_fatal_error("Can't return value from vararg function in memory"); |
| } |
| |
| int Offset = VA.getLocMemOffset(); |
| unsigned ObjSize = VA.getLocVT().getStoreSize(); |
| // Create the frame index object for the memory location. |
| int FI = MFI.CreateFixedObject(ObjSize, Offset, false); |
| |
| // Create a SelectionDAG node corresponding to a store |
| // to this memory location. |
| SDValue FIN = DAG.getFrameIndex(FI, MVT::i32); |
| MemOpChains.push_back(DAG.getStore( |
| Chain, dl, OutVals[i], FIN, |
| MachinePointerInfo::getFixedStack(DAG.getMachineFunction(), FI))); |
| } |
| |
| // Transform all store nodes into one single node because |
| // all stores are independent of each other. |
| if (!MemOpChains.empty()) |
| Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, MemOpChains); |
| |
| // Now handle return values copied to registers. |
| for (unsigned i = 0, e = RVLocs.size(); i != e; ++i) { |
| CCValAssign &VA = RVLocs[i]; |
| if (!VA.isRegLoc()) |
| continue; |
| // Copy the result values into the output registers. |
| Chain = DAG.getCopyToReg(Chain, dl, VA.getLocReg(), OutVals[i], Flag); |
| |
| // guarantee that all emitted copies are |
| // stuck together, avoiding something bad |
| Flag = Chain.getValue(1); |
| RetOps.push_back(DAG.getRegister(VA.getLocReg(), VA.getLocVT())); |
| } |
| |
| RetOps[0] = Chain; // Update chain. |
| |
| // Add the flag if we have it. |
| if (Flag.getNode()) |
| RetOps.push_back(Flag); |
| |
| // What to do with the RetOps? |
| return DAG.getNode(ARCISD::RET, dl, MVT::Other, RetOps); |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Target Optimization Hooks |
| //===----------------------------------------------------------------------===// |
| |
| SDValue ARCTargetLowering::PerformDAGCombine(SDNode *N, |
| DAGCombinerInfo &DCI) const { |
| return {}; |
| } |
| |
| //===----------------------------------------------------------------------===// |
| // Addressing mode description hooks |
| //===----------------------------------------------------------------------===// |
| |
| /// Return true if the addressing mode represented by AM is legal for this |
| /// target, for a load/store of the specified type. |
| bool ARCTargetLowering::isLegalAddressingMode(const DataLayout &DL, |
| const AddrMode &AM, Type *Ty, |
| unsigned AS, |
| Instruction *I) const { |
| return AM.Scale == 0; |
| } |
| |
| // Don't emit tail calls for the time being. |
| bool ARCTargetLowering::mayBeEmittedAsTailCall(const CallInst *CI) const { |
| return false; |
| } |
| |
| SDValue ARCTargetLowering::LowerFRAMEADDR(SDValue Op, SelectionDAG &DAG) const { |
| const ARCRegisterInfo &ARI = *Subtarget.getRegisterInfo(); |
| MachineFunction &MF = DAG.getMachineFunction(); |
| MachineFrameInfo &MFI = MF.getFrameInfo(); |
| MFI.setFrameAddressIsTaken(true); |
| |
| EVT VT = Op.getValueType(); |
| SDLoc dl(Op); |
| assert(cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue() == 0 && |
| "Only support lowering frame addr of current frame."); |
| Register FrameReg = ARI.getFrameRegister(MF); |
| return DAG.getCopyFromReg(DAG.getEntryNode(), dl, FrameReg, VT); |
| } |
| |
| SDValue ARCTargetLowering::LowerGlobalAddress(SDValue Op, |
| SelectionDAG &DAG) const { |
| const GlobalAddressSDNode *GN = cast<GlobalAddressSDNode>(Op); |
| const GlobalValue *GV = GN->getGlobal(); |
| SDLoc dl(GN); |
| int64_t Offset = GN->getOffset(); |
| SDValue GA = DAG.getTargetGlobalAddress(GV, dl, MVT::i32, Offset); |
| return DAG.getNode(ARCISD::GAWRAPPER, dl, MVT::i32, GA); |
| } |
| |
| static SDValue LowerVASTART(SDValue Op, SelectionDAG &DAG) { |
| MachineFunction &MF = DAG.getMachineFunction(); |
| auto *FuncInfo = MF.getInfo<ARCFunctionInfo>(); |
| |
| // vastart just stores the address of the VarArgsFrameIndex slot into the |
| // memory location argument. |
| SDLoc dl(Op); |
| EVT PtrVT = DAG.getTargetLoweringInfo().getPointerTy(DAG.getDataLayout()); |
| SDValue FR = DAG.getFrameIndex(FuncInfo->getVarArgsFrameIndex(), PtrVT); |
| const Value *SV = cast<SrcValueSDNode>(Op.getOperand(2))->getValue(); |
| return DAG.getStore(Op.getOperand(0), dl, FR, Op.getOperand(1), |
| MachinePointerInfo(SV)); |
| } |
| |
| SDValue ARCTargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) const { |
| switch (Op.getOpcode()) { |
| case ISD::GlobalAddress: |
| return LowerGlobalAddress(Op, DAG); |
| case ISD::FRAMEADDR: |
| return LowerFRAMEADDR(Op, DAG); |
| case ISD::SELECT_CC: |
| return LowerSELECT_CC(Op, DAG); |
| case ISD::BR_CC: |
| return LowerBR_CC(Op, DAG); |
| case ISD::SIGN_EXTEND_INREG: |
| return LowerSIGN_EXTEND_INREG(Op, DAG); |
| case ISD::JumpTable: |
| return LowerJumpTable(Op, DAG); |
| case ISD::VASTART: |
| return LowerVASTART(Op, DAG); |
| default: |
| llvm_unreachable("unimplemented operand"); |
| } |
| } |
