//===-- MipsISelLowering.cpp - Mips DAG Lowering Implementation -----------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This file defines the interfaces that Mips uses to lower LLVM code into a // selection DAG. // //===----------------------------------------------------------------------===// #define DEBUG_TYPE "mips-lower" #include "MipsISelLowering.h" #include "MipsMachineFunction.h" #include "MipsTargetMachine.h" #include "MipsTargetObjectFile.h" #include "MipsSubtarget.h" #include "llvm/DerivedTypes.h" #include "llvm/Function.h" #include "llvm/GlobalVariable.h" #include "llvm/Intrinsics.h" #include "llvm/CallingConv.h" #include "llvm/CodeGen/CallingConvLower.h" #include "llvm/CodeGen/MachineFrameInfo.h" #include "llvm/CodeGen/MachineFunction.h" #include "llvm/CodeGen/MachineInstrBuilder.h" #include "llvm/CodeGen/MachineRegisterInfo.h" #include "llvm/CodeGen/SelectionDAGISel.h" #include "llvm/CodeGen/ValueTypes.h" #include "llvm/Support/Debug.h" #include "llvm/Support/ErrorHandling.h" using namespace llvm; const char *MipsTargetLowering::getTargetNodeName(unsigned Opcode) const { switch (Opcode) { case MipsISD::JmpLink : return "MipsISD::JmpLink"; case MipsISD::Hi : return "MipsISD::Hi"; case MipsISD::Lo : return "MipsISD::Lo"; case MipsISD::GPRel : return "MipsISD::GPRel"; case MipsISD::Ret : return "MipsISD::Ret"; case MipsISD::FPBrcond : return "MipsISD::FPBrcond"; case MipsISD::FPCmp : return "MipsISD::FPCmp"; case MipsISD::CMovFP_T : return "MipsISD::CMovFP_T"; case MipsISD::CMovFP_F : return "MipsISD::CMovFP_F"; case MipsISD::FPRound : return "MipsISD::FPRound"; case MipsISD::MAdd : return "MipsISD::MAdd"; case MipsISD::MAddu : return "MipsISD::MAddu"; case MipsISD::MSub : return "MipsISD::MSub"; case MipsISD::MSubu : return "MipsISD::MSubu"; case MipsISD::DivRem : return "MipsISD::DivRem"; case MipsISD::DivRemU : return "MipsISD::DivRemU"; case MipsISD::BuildPairF64: return "MipsISD::BuildPairF64"; case MipsISD::ExtractElementF64: return "MipsISD::ExtractElementF64"; default : return NULL; } } MipsTargetLowering:: MipsTargetLowering(MipsTargetMachine &TM) : TargetLowering(TM, new MipsTargetObjectFile()) { Subtarget = &TM.getSubtarget(); // Mips does not have i1 type, so use i32 for // setcc operations results (slt, sgt, ...). setBooleanContents(ZeroOrOneBooleanContent); // Set up the register classes addRegisterClass(MVT::i32, Mips::CPURegsRegisterClass); addRegisterClass(MVT::f32, Mips::FGR32RegisterClass); // When dealing with single precision only, use libcalls if (!Subtarget->isSingleFloat()) if (!Subtarget->isFP64bit()) addRegisterClass(MVT::f64, Mips::AFGR64RegisterClass); // Load extented operations for i1 types must be promoted setLoadExtAction(ISD::EXTLOAD, MVT::i1, Promote); setLoadExtAction(ISD::ZEXTLOAD, MVT::i1, Promote); setLoadExtAction(ISD::SEXTLOAD, MVT::i1, Promote); // MIPS doesn't have extending float->double load/store setLoadExtAction(ISD::EXTLOAD, MVT::f32, Expand); setTruncStoreAction(MVT::f64, MVT::f32, Expand); // Used by legalize types to correctly generate the setcc result. // Without this, every float setcc comes with a AND/OR with the result, // we don't want this, since the fpcmp result goes to a flag register, // which is used implicitly by brcond and select operations. AddPromotedToType(ISD::SETCC, MVT::i1, MVT::i32); // Mips Custom Operations setOperationAction(ISD::GlobalAddress, MVT::i32, Custom); setOperationAction(ISD::BlockAddress, MVT::i32, Custom); setOperationAction(ISD::GlobalTLSAddress, MVT::i32, Custom); setOperationAction(ISD::JumpTable, MVT::i32, Custom); setOperationAction(ISD::ConstantPool, MVT::i32, Custom); setOperationAction(ISD::SELECT, MVT::f32, Custom); setOperationAction(ISD::SELECT, MVT::f64, Custom); setOperationAction(ISD::SELECT, MVT::i32, Custom); setOperationAction(ISD::BRCOND, MVT::Other, Custom); setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32, Custom); setOperationAction(ISD::FP_TO_SINT, MVT::i32, Custom); setOperationAction(ISD::VASTART, MVT::Other, Custom); setOperationAction(ISD::SDIV, MVT::i32, Expand); setOperationAction(ISD::SREM, MVT::i32, Expand); setOperationAction(ISD::UDIV, MVT::i32, Expand); setOperationAction(ISD::UREM, MVT::i32, Expand); // Operations not directly supported by Mips. setOperationAction(ISD::BR_JT, MVT::Other, Expand); setOperationAction(ISD::BR_CC, MVT::Other, Expand); setOperationAction(ISD::SELECT_CC, MVT::Other, Expand); setOperationAction(ISD::UINT_TO_FP, MVT::i32, Expand); setOperationAction(ISD::FP_TO_UINT, MVT::i32, Expand); setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i1, Expand); setOperationAction(ISD::CTPOP, MVT::i32, Expand); setOperationAction(ISD::CTTZ, MVT::i32, Expand); setOperationAction(ISD::ROTL, MVT::i32, Expand); if (!Subtarget->isMips32r2()) setOperationAction(ISD::ROTR, MVT::i32, Expand); setOperationAction(ISD::SHL_PARTS, MVT::i32, Expand); setOperationAction(ISD::SRA_PARTS, MVT::i32, Expand); setOperationAction(ISD::SRL_PARTS, MVT::i32, Expand); setOperationAction(ISD::FCOPYSIGN, MVT::f32, Expand); setOperationAction(ISD::FCOPYSIGN, MVT::f64, Expand); setOperationAction(ISD::FSIN, MVT::f32, Expand); setOperationAction(ISD::FSIN, MVT::f64, Expand); setOperationAction(ISD::FCOS, MVT::f32, Expand); setOperationAction(ISD::FCOS, MVT::f64, Expand); setOperationAction(ISD::FPOWI, MVT::f32, Expand); setOperationAction(ISD::FPOW, MVT::f32, Expand); setOperationAction(ISD::FLOG, MVT::f32, Expand); setOperationAction(ISD::FLOG2, MVT::f32, Expand); setOperationAction(ISD::FLOG10, MVT::f32, Expand); setOperationAction(ISD::FEXP, MVT::f32, Expand); setOperationAction(ISD::EH_LABEL, MVT::Other, Expand); setOperationAction(ISD::VAARG, MVT::Other, Expand); setOperationAction(ISD::VACOPY, MVT::Other, Expand); setOperationAction(ISD::VAEND, MVT::Other, Expand); // Use the default for now setOperationAction(ISD::STACKSAVE, MVT::Other, Expand); setOperationAction(ISD::STACKRESTORE, MVT::Other, Expand); setOperationAction(ISD::MEMBARRIER, MVT::Other, Expand); if (Subtarget->isSingleFloat()) setOperationAction(ISD::SELECT_CC, MVT::f64, Expand); if (!Subtarget->hasSEInReg()) { setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i8, Expand); setOperationAction(ISD::SIGN_EXTEND_INREG, MVT::i16, Expand); } if (!Subtarget->hasBitCount()) setOperationAction(ISD::CTLZ, MVT::i32, Expand); if (!Subtarget->hasSwap()) setOperationAction(ISD::BSWAP, MVT::i32, Expand); setTargetDAGCombine(ISD::ADDE); setTargetDAGCombine(ISD::SUBE); setTargetDAGCombine(ISD::SDIVREM); setTargetDAGCombine(ISD::UDIVREM); setTargetDAGCombine(ISD::SETCC); setMinFunctionAlignment(2); setStackPointerRegisterToSaveRestore(Mips::SP); computeRegisterProperties(); } MVT::SimpleValueType MipsTargetLowering::getSetCCResultType(EVT VT) const { return MVT::i32; } // SelectMadd - // Transforms a subgraph in CurDAG if the following pattern is found: // (addc multLo, Lo0), (adde multHi, Hi0), // where, // multHi/Lo: product of multiplication // Lo0: initial value of Lo register // Hi0: initial value of Hi register // Return true if pattern matching was successful. static bool SelectMadd(SDNode* ADDENode, SelectionDAG* CurDAG) { // ADDENode's second operand must be a flag output of an ADDC node in order // for the matching to be successful. SDNode* ADDCNode = ADDENode->getOperand(2).getNode(); if (ADDCNode->getOpcode() != ISD::ADDC) return false; SDValue MultHi = ADDENode->getOperand(0); SDValue MultLo = ADDCNode->getOperand(0); SDNode* MultNode = MultHi.getNode(); unsigned MultOpc = MultHi.getOpcode(); // MultHi and MultLo must be generated by the same node, if (MultLo.getNode() != MultNode) return false; // and it must be a multiplication. if (MultOpc != ISD::SMUL_LOHI && MultOpc != ISD::UMUL_LOHI) return false; // MultLo amd MultHi must be the first and second output of MultNode // respectively. if (MultHi.getResNo() != 1 || MultLo.getResNo() != 0) return false; // Transform this to a MADD only if ADDENode and ADDCNode are the only users // of the values of MultNode, in which case MultNode will be removed in later // phases. // If there exist users other than ADDENode or ADDCNode, this function returns // here, which will result in MultNode being mapped to a single MULT // instruction node rather than a pair of MULT and MADD instructions being // produced. if (!MultHi.hasOneUse() || !MultLo.hasOneUse()) return false; SDValue Chain = CurDAG->getEntryNode(); DebugLoc dl = ADDENode->getDebugLoc(); // create MipsMAdd(u) node MultOpc = MultOpc == ISD::UMUL_LOHI ? MipsISD::MAddu : MipsISD::MAdd; SDValue MAdd = CurDAG->getNode(MultOpc, dl, MVT::Glue, MultNode->getOperand(0),// Factor 0 MultNode->getOperand(1),// Factor 1 ADDCNode->getOperand(1),// Lo0 ADDENode->getOperand(1));// Hi0 // create CopyFromReg nodes SDValue CopyFromLo = CurDAG->getCopyFromReg(Chain, dl, Mips::LO, MVT::i32, MAdd); SDValue CopyFromHi = CurDAG->getCopyFromReg(CopyFromLo.getValue(1), dl, Mips::HI, MVT::i32, CopyFromLo.getValue(2)); // replace uses of adde and addc here if (!SDValue(ADDCNode, 0).use_empty()) CurDAG->ReplaceAllUsesOfValueWith(SDValue(ADDCNode, 0), CopyFromLo); if (!SDValue(ADDENode, 0).use_empty()) CurDAG->ReplaceAllUsesOfValueWith(SDValue(ADDENode, 0), CopyFromHi); return true; } // SelectMsub - // Transforms a subgraph in CurDAG if the following pattern is found: // (addc Lo0, multLo), (sube Hi0, multHi), // where, // multHi/Lo: product of multiplication // Lo0: initial value of Lo register // Hi0: initial value of Hi register // Return true if pattern matching was successful. static bool SelectMsub(SDNode* SUBENode, SelectionDAG* CurDAG) { // SUBENode's second operand must be a flag output of an SUBC node in order // for the matching to be successful. SDNode* SUBCNode = SUBENode->getOperand(2).getNode(); if (SUBCNode->getOpcode() != ISD::SUBC) return false; SDValue MultHi = SUBENode->getOperand(1); SDValue MultLo = SUBCNode->getOperand(1); SDNode* MultNode = MultHi.getNode(); unsigned MultOpc = MultHi.getOpcode(); // MultHi and MultLo must be generated by the same node, if (MultLo.getNode() != MultNode) return false; // and it must be a multiplication. if (MultOpc != ISD::SMUL_LOHI && MultOpc != ISD::UMUL_LOHI) return false; // MultLo amd MultHi must be the first and second output of MultNode // respectively. if (MultHi.getResNo() != 1 || MultLo.getResNo() != 0) return false; // Transform this to a MSUB only if SUBENode and SUBCNode are the only users // of the values of MultNode, in which case MultNode will be removed in later // phases. // If there exist users other than SUBENode or SUBCNode, this function returns // here, which will result in MultNode being mapped to a single MULT // instruction node rather than a pair of MULT and MSUB instructions being // produced. if (!MultHi.hasOneUse() || !MultLo.hasOneUse()) return false; SDValue Chain = CurDAG->getEntryNode(); DebugLoc dl = SUBENode->getDebugLoc(); // create MipsSub(u) node MultOpc = MultOpc == ISD::UMUL_LOHI ? MipsISD::MSubu : MipsISD::MSub; SDValue MSub = CurDAG->getNode(MultOpc, dl, MVT::Glue, MultNode->getOperand(0),// Factor 0 MultNode->getOperand(1),// Factor 1 SUBCNode->getOperand(0),// Lo0 SUBENode->getOperand(0));// Hi0 // create CopyFromReg nodes SDValue CopyFromLo = CurDAG->getCopyFromReg(Chain, dl, Mips::LO, MVT::i32, MSub); SDValue CopyFromHi = CurDAG->getCopyFromReg(CopyFromLo.getValue(1), dl, Mips::HI, MVT::i32, CopyFromLo.getValue(2)); // replace uses of sube and subc here if (!SDValue(SUBCNode, 0).use_empty()) CurDAG->ReplaceAllUsesOfValueWith(SDValue(SUBCNode, 0), CopyFromLo); if (!SDValue(SUBENode, 0).use_empty()) CurDAG->ReplaceAllUsesOfValueWith(SDValue(SUBENode, 0), CopyFromHi); return true; } static SDValue PerformADDECombine(SDNode *N, SelectionDAG& DAG, TargetLowering::DAGCombinerInfo &DCI, const MipsSubtarget* Subtarget) { if (DCI.isBeforeLegalize()) return SDValue(); if (Subtarget->isMips32() && SelectMadd(N, &DAG)) return SDValue(N, 0); return SDValue(); } static SDValue PerformSUBECombine(SDNode *N, SelectionDAG& DAG, TargetLowering::DAGCombinerInfo &DCI, const MipsSubtarget* Subtarget) { if (DCI.isBeforeLegalize()) return SDValue(); if (Subtarget->isMips32() && SelectMsub(N, &DAG)) return SDValue(N, 0); return SDValue(); } static SDValue PerformDivRemCombine(SDNode *N, SelectionDAG& DAG, TargetLowering::DAGCombinerInfo &DCI, const MipsSubtarget* Subtarget) { if (DCI.isBeforeLegalizeOps()) return SDValue(); unsigned opc = N->getOpcode() == ISD::SDIVREM ? MipsISD::DivRem : MipsISD::DivRemU; DebugLoc dl = N->getDebugLoc(); SDValue DivRem = DAG.getNode(opc, dl, MVT::Glue, N->getOperand(0), N->getOperand(1)); SDValue InChain = DAG.getEntryNode(); SDValue InGlue = DivRem; // insert MFLO if (N->hasAnyUseOfValue(0)) { SDValue CopyFromLo = DAG.getCopyFromReg(InChain, dl, Mips::LO, MVT::i32, InGlue); DAG.ReplaceAllUsesOfValueWith(SDValue(N, 0), CopyFromLo); InChain = CopyFromLo.getValue(1); InGlue = CopyFromLo.getValue(2); } // insert MFHI if (N->hasAnyUseOfValue(1)) { SDValue CopyFromHi = DAG.getCopyFromReg(InChain, dl, Mips::HI, MVT::i32, InGlue); DAG.ReplaceAllUsesOfValueWith(SDValue(N, 1), CopyFromHi); } return SDValue(); } static Mips::CondCode FPCondCCodeToFCC(ISD::CondCode CC) { switch (CC) { default: llvm_unreachable("Unknown fp condition code!"); case ISD::SETEQ: case ISD::SETOEQ: return Mips::FCOND_OEQ; case ISD::SETUNE: return Mips::FCOND_UNE; case ISD::SETLT: case ISD::SETOLT: return Mips::FCOND_OLT; case ISD::SETGT: case ISD::SETOGT: return Mips::FCOND_OGT; case ISD::SETLE: case ISD::SETOLE: return Mips::FCOND_OLE; case ISD::SETGE: case ISD::SETOGE: return Mips::FCOND_OGE; case ISD::SETULT: return Mips::FCOND_ULT; case ISD::SETULE: return Mips::FCOND_ULE; case ISD::SETUGT: return Mips::FCOND_UGT; case ISD::SETUGE: return Mips::FCOND_UGE; case ISD::SETUO: return Mips::FCOND_UN; case ISD::SETO: return Mips::FCOND_OR; case ISD::SETNE: case ISD::SETONE: return Mips::FCOND_ONE; case ISD::SETUEQ: return Mips::FCOND_UEQ; } } // Returns true if condition code has to be inverted. static bool InvertFPCondCode(Mips::CondCode CC) { if (CC >= Mips::FCOND_F && CC <= Mips::FCOND_NGT) return false; if (CC >= Mips::FCOND_T && CC <= Mips::FCOND_GT) return true; assert(false && "Illegal Condition Code"); return false; } // Creates and returns an FPCmp node from a setcc node. // Returns Op if setcc is not a floating point comparison. static SDValue CreateFPCmp(SelectionDAG& DAG, const SDValue& Op) { // must be a SETCC node if (Op.getOpcode() != ISD::SETCC) return Op; SDValue LHS = Op.getOperand(0); if (!LHS.getValueType().isFloatingPoint()) return Op; SDValue RHS = Op.getOperand(1); DebugLoc dl = Op.getDebugLoc(); // Assume the 3rd operand is a CondCodeSDNode. Add code to check the type of // node if necessary. ISD::CondCode CC = cast(Op.getOperand(2))->get(); return DAG.getNode(MipsISD::FPCmp, dl, MVT::Glue, LHS, RHS, DAG.getConstant(FPCondCCodeToFCC(CC), MVT::i32)); } // Creates and returns a CMovFPT/F node. static SDValue CreateCMovFP(SelectionDAG& DAG, SDValue Cond, SDValue True, SDValue False, DebugLoc DL) { bool invert = InvertFPCondCode((Mips::CondCode) cast(Cond.getOperand(2)) ->getSExtValue()); return DAG.getNode((invert ? MipsISD::CMovFP_F : MipsISD::CMovFP_T), DL, True.getValueType(), True, False, Cond); } static SDValue PerformSETCCCombine(SDNode *N, SelectionDAG& DAG, TargetLowering::DAGCombinerInfo &DCI, const MipsSubtarget* Subtarget) { if (DCI.isBeforeLegalizeOps()) return SDValue(); SDValue Cond = CreateFPCmp(DAG, SDValue(N, 0)); if (Cond.getOpcode() != MipsISD::FPCmp) return SDValue(); SDValue True = DAG.getConstant(1, MVT::i32); SDValue False = DAG.getConstant(0, MVT::i32); return CreateCMovFP(DAG, Cond, True, False, N->getDebugLoc()); } SDValue MipsTargetLowering::PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI) const { SelectionDAG &DAG = DCI.DAG; unsigned opc = N->getOpcode(); switch (opc) { default: break; case ISD::ADDE: return PerformADDECombine(N, DAG, DCI, Subtarget); case ISD::SUBE: return PerformSUBECombine(N, DAG, DCI, Subtarget); case ISD::SDIVREM: case ISD::UDIVREM: return PerformDivRemCombine(N, DAG, DCI, Subtarget); case ISD::SETCC: return PerformSETCCCombine(N, DAG, DCI, Subtarget); } return SDValue(); } SDValue MipsTargetLowering:: LowerOperation(SDValue Op, SelectionDAG &DAG) const { switch (Op.getOpcode()) { case ISD::BRCOND: return LowerBRCOND(Op, DAG); case ISD::ConstantPool: return LowerConstantPool(Op, DAG); case ISD::DYNAMIC_STACKALLOC: return LowerDYNAMIC_STACKALLOC(Op, DAG); case ISD::FP_TO_SINT: return LowerFP_TO_SINT(Op, DAG); case ISD::GlobalAddress: return LowerGlobalAddress(Op, DAG); case ISD::BlockAddress: return LowerBlockAddress(Op, DAG); case ISD::GlobalTLSAddress: return LowerGlobalTLSAddress(Op, DAG); case ISD::JumpTable: return LowerJumpTable(Op, DAG); case ISD::SELECT: return LowerSELECT(Op, DAG); case ISD::VASTART: return LowerVASTART(Op, DAG); } return SDValue(); } //===----------------------------------------------------------------------===// // Lower helper functions //===----------------------------------------------------------------------===// // AddLiveIn - This helper function adds the specified physical register to the // MachineFunction as a live in value. It also creates a corresponding // virtual register for it. static unsigned AddLiveIn(MachineFunction &MF, unsigned PReg, TargetRegisterClass *RC) { assert(RC->contains(PReg) && "Not the correct regclass!"); unsigned VReg = MF.getRegInfo().createVirtualRegister(RC); MF.getRegInfo().addLiveIn(PReg, VReg); return VReg; } // Get fp branch code (not opcode) from condition code. static Mips::FPBranchCode GetFPBranchCodeFromCond(Mips::CondCode CC) { if (CC >= Mips::FCOND_F && CC <= Mips::FCOND_NGT) return Mips::BRANCH_T; if (CC >= Mips::FCOND_T && CC <= Mips::FCOND_GT) return Mips::BRANCH_F; return Mips::BRANCH_INVALID; } MachineBasicBlock * MipsTargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI, MachineBasicBlock *BB) const { // There is no need to expand CMov instructions if target has // conditional moves. if (Subtarget->hasCondMov()) return BB; const TargetInstrInfo *TII = getTargetMachine().getInstrInfo(); bool isFPCmp = false; DebugLoc dl = MI->getDebugLoc(); unsigned Opc; switch (MI->getOpcode()) { default: assert(false && "Unexpected instr type to insert"); case Mips::MOVT: case Mips::MOVT_S: case Mips::MOVT_D: isFPCmp = true; Opc = Mips::BC1F; break; case Mips::MOVF: case Mips::MOVF_S: case Mips::MOVF_D: isFPCmp = true; Opc = Mips::BC1T; break; case Mips::MOVZ_I: case Mips::MOVZ_S: case Mips::MOVZ_D: Opc = Mips::BNE; break; case Mips::MOVN_I: case Mips::MOVN_S: case Mips::MOVN_D: Opc = Mips::BEQ; break; } // To "insert" a SELECT_CC instruction, we actually have to insert the // diamond control-flow pattern. The incoming instruction knows the // destination vreg to set, the condition code register to branch on, the // true/false values to select between, and a branch opcode to use. const BasicBlock *LLVM_BB = BB->getBasicBlock(); MachineFunction::iterator It = BB; ++It; // thisMBB: // ... // TrueVal = ... // setcc r1, r2, r3 // bNE r1, r0, copy1MBB // fallthrough --> copy0MBB MachineBasicBlock *thisMBB = BB; MachineFunction *F = BB->getParent(); MachineBasicBlock *copy0MBB = F->CreateMachineBasicBlock(LLVM_BB); MachineBasicBlock *sinkMBB = F->CreateMachineBasicBlock(LLVM_BB); F->insert(It, copy0MBB); F->insert(It, sinkMBB); // Transfer the remainder of BB and its successor edges to sinkMBB. sinkMBB->splice(sinkMBB->begin(), BB, llvm::next(MachineBasicBlock::iterator(MI)), BB->end()); sinkMBB->transferSuccessorsAndUpdatePHIs(BB); // Next, add the true and fallthrough blocks as its successors. BB->addSuccessor(copy0MBB); BB->addSuccessor(sinkMBB); // Emit the right instruction according to the type of the operands compared if (isFPCmp) BuildMI(BB, dl, TII->get(Opc)).addMBB(sinkMBB); else BuildMI(BB, dl, TII->get(Opc)).addReg(MI->getOperand(2).getReg()) .addReg(Mips::ZERO).addMBB(sinkMBB); // copy0MBB: // %FalseValue = ... // # fallthrough to sinkMBB BB = copy0MBB; // Update machine-CFG edges BB->addSuccessor(sinkMBB); // sinkMBB: // %Result = phi [ %TrueValue, thisMBB ], [ %FalseValue, copy0MBB ] // ... BB = sinkMBB; if (isFPCmp) BuildMI(*BB, BB->begin(), dl, TII->get(Mips::PHI), MI->getOperand(0).getReg()) .addReg(MI->getOperand(2).getReg()).addMBB(thisMBB) .addReg(MI->getOperand(1).getReg()).addMBB(copy0MBB); else BuildMI(*BB, BB->begin(), dl, TII->get(Mips::PHI), MI->getOperand(0).getReg()) .addReg(MI->getOperand(3).getReg()).addMBB(thisMBB) .addReg(MI->getOperand(1).getReg()).addMBB(copy0MBB); MI->eraseFromParent(); // The pseudo instruction is gone now. return BB; } //===----------------------------------------------------------------------===// // Misc Lower Operation implementation //===----------------------------------------------------------------------===// SDValue MipsTargetLowering:: LowerFP_TO_SINT(SDValue Op, SelectionDAG &DAG) const { if (!Subtarget->isMips1()) return Op; MachineFunction &MF = DAG.getMachineFunction(); unsigned CCReg = AddLiveIn(MF, Mips::FCR31, Mips::CCRRegisterClass); SDValue Chain = DAG.getEntryNode(); DebugLoc dl = Op.getDebugLoc(); SDValue Src = Op.getOperand(0); // Set the condition register SDValue CondReg = DAG.getCopyFromReg(Chain, dl, CCReg, MVT::i32); CondReg = DAG.getCopyToReg(Chain, dl, Mips::AT, CondReg); CondReg = DAG.getCopyFromReg(CondReg, dl, Mips::AT, MVT::i32); SDValue Cst = DAG.getConstant(3, MVT::i32); SDValue Or = DAG.getNode(ISD::OR, dl, MVT::i32, CondReg, Cst); Cst = DAG.getConstant(2, MVT::i32); SDValue Xor = DAG.getNode(ISD::XOR, dl, MVT::i32, Or, Cst); SDValue InFlag(0, 0); CondReg = DAG.getCopyToReg(Chain, dl, Mips::FCR31, Xor, InFlag); // Emit the round instruction and bit convert to integer SDValue Trunc = DAG.getNode(MipsISD::FPRound, dl, MVT::f32, Src, CondReg.getValue(1)); SDValue BitCvt = DAG.getNode(ISD::BITCAST, dl, MVT::i32, Trunc); return BitCvt; } SDValue MipsTargetLowering:: LowerDYNAMIC_STACKALLOC(SDValue Op, SelectionDAG &DAG) const { SDValue Chain = Op.getOperand(0); SDValue Size = Op.getOperand(1); DebugLoc dl = Op.getDebugLoc(); // Get a reference from Mips stack pointer SDValue StackPointer = DAG.getCopyFromReg(Chain, dl, Mips::SP, MVT::i32); // Subtract the dynamic size from the actual stack size to // obtain the new stack size. SDValue Sub = DAG.getNode(ISD::SUB, dl, MVT::i32, StackPointer, Size); // The Sub result contains the new stack start address, so it // must be placed in the stack pointer register. Chain = DAG.getCopyToReg(StackPointer.getValue(1), dl, Mips::SP, Sub); // This node always has two return values: a new stack pointer // value and a chain SDValue Ops[2] = { Sub, Chain }; return DAG.getMergeValues(Ops, 2, dl); } SDValue MipsTargetLowering:: LowerBRCOND(SDValue Op, SelectionDAG &DAG) const { // The first operand is the chain, the second is the condition, the third is // the block to branch to if the condition is true. SDValue Chain = Op.getOperand(0); SDValue Dest = Op.getOperand(2); DebugLoc dl = Op.getDebugLoc(); SDValue CondRes = CreateFPCmp(DAG, Op.getOperand(1)); // Return if flag is not set by a floating point comparison. if (CondRes.getOpcode() != MipsISD::FPCmp) return Op; SDValue CCNode = CondRes.getOperand(2); Mips::CondCode CC = (Mips::CondCode)cast(CCNode)->getZExtValue(); SDValue BrCode = DAG.getConstant(GetFPBranchCodeFromCond(CC), MVT::i32); return DAG.getNode(MipsISD::FPBrcond, dl, Op.getValueType(), Chain, BrCode, Dest, CondRes); } SDValue MipsTargetLowering:: LowerSELECT(SDValue Op, SelectionDAG &DAG) const { SDValue Cond = CreateFPCmp(DAG, Op.getOperand(0)); // Return if flag is not set by a floating point comparison. if (Cond.getOpcode() != MipsISD::FPCmp) return Op; return CreateCMovFP(DAG, Cond, Op.getOperand(1), Op.getOperand(2), Op.getDebugLoc()); } SDValue MipsTargetLowering::LowerGlobalAddress(SDValue Op, SelectionDAG &DAG) const { // FIXME there isn't actually debug info here DebugLoc dl = Op.getDebugLoc(); const GlobalValue *GV = cast(Op)->getGlobal(); if (getTargetMachine().getRelocationModel() != Reloc::PIC_) { SDVTList VTs = DAG.getVTList(MVT::i32); MipsTargetObjectFile &TLOF = (MipsTargetObjectFile&)getObjFileLowering(); // %gp_rel relocation if (TLOF.IsGlobalInSmallSection(GV, getTargetMachine())) { SDValue GA = DAG.getTargetGlobalAddress(GV, dl, MVT::i32, 0, MipsII::MO_GPREL); SDValue GPRelNode = DAG.getNode(MipsISD::GPRel, dl, VTs, &GA, 1); SDValue GOT = DAG.getGLOBAL_OFFSET_TABLE(MVT::i32); return DAG.getNode(ISD::ADD, dl, MVT::i32, GOT, GPRelNode); } // %hi/%lo relocation SDValue GAHi = DAG.getTargetGlobalAddress(GV, dl, MVT::i32, 0, MipsII::MO_ABS_HI); SDValue GALo = DAG.getTargetGlobalAddress(GV, dl, MVT::i32, 0, MipsII::MO_ABS_LO); SDValue HiPart = DAG.getNode(MipsISD::Hi, dl, VTs, &GAHi, 1); SDValue Lo = DAG.getNode(MipsISD::Lo, dl, MVT::i32, GALo); return DAG.getNode(ISD::ADD, dl, MVT::i32, HiPart, Lo); } else { SDValue GA = DAG.getTargetGlobalAddress(GV, dl, MVT::i32, 0, MipsII::MO_GOT); SDValue ResNode = DAG.getLoad(MVT::i32, dl, DAG.getEntryNode(), GA, MachinePointerInfo(), false, false, 0); // On functions and global targets not internal linked only // a load from got/GP is necessary for PIC to work. if (!GV->hasInternalLinkage() && (!GV->hasLocalLinkage() || isa(GV))) return ResNode; SDValue GALo = DAG.getTargetGlobalAddress(GV, dl, MVT::i32, 0, MipsII::MO_ABS_LO); SDValue Lo = DAG.getNode(MipsISD::Lo, dl, MVT::i32, GALo); return DAG.getNode(ISD::ADD, dl, MVT::i32, ResNode, Lo); } llvm_unreachable("Dont know how to handle GlobalAddress"); return SDValue(0,0); } SDValue MipsTargetLowering::LowerBlockAddress(SDValue Op, SelectionDAG &DAG) const { const BlockAddress *BA = cast(Op)->getBlockAddress(); // FIXME there isn't actually debug info here DebugLoc dl = Op.getDebugLoc(); if (getTargetMachine().getRelocationModel() != Reloc::PIC_) { // %hi/%lo relocation SDValue BAHi = DAG.getBlockAddress(BA, MVT::i32, true, MipsII::MO_ABS_HI); SDValue BALo = DAG.getBlockAddress(BA, MVT::i32, true, MipsII::MO_ABS_LO); SDValue Hi = DAG.getNode(MipsISD::Hi, dl, MVT::i32, BAHi); SDValue Lo = DAG.getNode(MipsISD::Lo, dl, MVT::i32, BALo); return DAG.getNode(ISD::ADD, dl, MVT::i32, Hi, Lo); } SDValue BAGOTOffset = DAG.getBlockAddress(BA, MVT::i32, true, MipsII::MO_GOT); SDValue BALOOffset = DAG.getBlockAddress(BA, MVT::i32, true, MipsII::MO_ABS_LO); SDValue Load = DAG.getLoad(MVT::i32, dl, DAG.getEntryNode(), BAGOTOffset, MachinePointerInfo(), false, false, 0); SDValue Lo = DAG.getNode(MipsISD::Lo, dl, MVT::i32, BALOOffset); return DAG.getNode(ISD::ADD, dl, MVT::i32, Load, Lo); } SDValue MipsTargetLowering:: LowerGlobalTLSAddress(SDValue Op, SelectionDAG &DAG) const { llvm_unreachable("TLS not implemented for MIPS."); return SDValue(); // Not reached } SDValue MipsTargetLowering:: LowerJumpTable(SDValue Op, SelectionDAG &DAG) const { SDValue ResNode; SDValue HiPart; // FIXME there isn't actually debug info here DebugLoc dl = Op.getDebugLoc(); bool IsPIC = getTargetMachine().getRelocationModel() == Reloc::PIC_; unsigned char OpFlag = IsPIC ? MipsII::MO_GOT : MipsII::MO_ABS_HI; EVT PtrVT = Op.getValueType(); JumpTableSDNode *JT = cast(Op); SDValue JTI = DAG.getTargetJumpTable(JT->getIndex(), PtrVT, OpFlag); if (!IsPIC) { SDValue Ops[] = { JTI }; HiPart = DAG.getNode(MipsISD::Hi, dl, DAG.getVTList(MVT::i32), Ops, 1); } else // Emit Load from Global Pointer HiPart = DAG.getLoad(MVT::i32, dl, DAG.getEntryNode(), JTI, MachinePointerInfo(), false, false, 0); SDValue JTILo = DAG.getTargetJumpTable(JT->getIndex(), PtrVT, MipsII::MO_ABS_LO); SDValue Lo = DAG.getNode(MipsISD::Lo, dl, MVT::i32, JTILo); ResNode = DAG.getNode(ISD::ADD, dl, MVT::i32, HiPart, Lo); return ResNode; } SDValue MipsTargetLowering:: LowerConstantPool(SDValue Op, SelectionDAG &DAG) const { SDValue ResNode; ConstantPoolSDNode *N = cast(Op); const Constant *C = N->getConstVal(); // FIXME there isn't actually debug info here DebugLoc dl = Op.getDebugLoc(); // gp_rel relocation // FIXME: we should reference the constant pool using small data sections, // but the asm printer currently doesn't support this feature without // hacking it. This feature should come soon so we can uncomment the // stuff below. //if (IsInSmallSection(C->getType())) { // SDValue GPRelNode = DAG.getNode(MipsISD::GPRel, MVT::i32, CP); // SDValue GOT = DAG.getGLOBAL_OFFSET_TABLE(MVT::i32); // ResNode = DAG.getNode(ISD::ADD, MVT::i32, GOT, GPRelNode); if (getTargetMachine().getRelocationModel() != Reloc::PIC_) { SDValue CPHi = DAG.getTargetConstantPool(C, MVT::i32, N->getAlignment(), N->getOffset(), MipsII::MO_ABS_HI); SDValue CPLo = DAG.getTargetConstantPool(C, MVT::i32, N->getAlignment(), N->getOffset(), MipsII::MO_ABS_LO); SDValue HiPart = DAG.getNode(MipsISD::Hi, dl, MVT::i32, CPHi); SDValue Lo = DAG.getNode(MipsISD::Lo, dl, MVT::i32, CPLo); ResNode = DAG.getNode(ISD::ADD, dl, MVT::i32, HiPart, Lo); } else { SDValue CP = DAG.getTargetConstantPool(C, MVT::i32, N->getAlignment(), N->getOffset(), MipsII::MO_GOT); SDValue Load = DAG.getLoad(MVT::i32, dl, DAG.getEntryNode(), CP, MachinePointerInfo::getConstantPool(), false, false, 0); SDValue CPLo = DAG.getTargetConstantPool(C, MVT::i32, N->getAlignment(), N->getOffset(), MipsII::MO_ABS_LO); SDValue Lo = DAG.getNode(MipsISD::Lo, dl, MVT::i32, CPLo); ResNode = DAG.getNode(ISD::ADD, dl, MVT::i32, Load, Lo); } return ResNode; } SDValue MipsTargetLowering::LowerVASTART(SDValue Op, SelectionDAG &DAG) const { MachineFunction &MF = DAG.getMachineFunction(); MipsFunctionInfo *FuncInfo = MF.getInfo(); DebugLoc dl = Op.getDebugLoc(); SDValue FI = DAG.getFrameIndex(FuncInfo->getVarArgsFrameIndex(), getPointerTy()); // vastart just stores the address of the VarArgsFrameIndex slot into the // memory location argument. const Value *SV = cast(Op.getOperand(2))->getValue(); return DAG.getStore(Op.getOperand(0), dl, FI, Op.getOperand(1), MachinePointerInfo(SV), false, false, 0); } //===----------------------------------------------------------------------===// // Calling Convention Implementation //===----------------------------------------------------------------------===// #include "MipsGenCallingConv.inc" //===----------------------------------------------------------------------===// // TODO: Implement a generic logic using tblgen that can support this. // Mips O32 ABI rules: // --- // i32 - Passed in A0, A1, A2, A3 and stack // f32 - Only passed in f32 registers if no int reg has been used yet to hold // an argument. Otherwise, passed in A1, A2, A3 and stack. // f64 - Only passed in two aliased f32 registers if no int reg has been used // yet to hold an argument. Otherwise, use A2, A3 and stack. If A1 is // not used, it must be shadowed. If only A3 is avaiable, shadow it and // go to stack. // // For vararg functions, all arguments are passed in A0, A1, A2, A3 and stack. //===----------------------------------------------------------------------===// static bool CC_MipsO32(unsigned ValNo, MVT ValVT, MVT LocVT, CCValAssign::LocInfo LocInfo, ISD::ArgFlagsTy ArgFlags, CCState &State) { static const unsigned IntRegsSize=4, FloatRegsSize=2; static const unsigned IntRegs[] = { Mips::A0, Mips::A1, Mips::A2, Mips::A3 }; static const unsigned F32Regs[] = { Mips::F12, Mips::F14 }; static const unsigned F64Regs[] = { Mips::D6, Mips::D7 }; // Promote i8 and i16 if (LocVT == MVT::i8 || LocVT == MVT::i16) { LocVT = MVT::i32; if (ArgFlags.isSExt()) LocInfo = CCValAssign::SExt; else if (ArgFlags.isZExt()) LocInfo = CCValAssign::ZExt; else LocInfo = CCValAssign::AExt; } unsigned Reg; // f32 and f64 are allocated in A0, A1, A2, A3 when either of the following // is true: function is vararg, argument is 3rd or higher, there is previous // argument which is not f32 or f64. bool AllocateFloatsInIntReg = State.isVarArg() || ValNo > 1 || State.getFirstUnallocated(F32Regs, FloatRegsSize) != ValNo; unsigned OrigAlign = ArgFlags.getOrigAlign(); bool isI64 = (ValVT == MVT::i32 && OrigAlign == 8); if (ValVT == MVT::i32 || (ValVT == MVT::f32 && AllocateFloatsInIntReg)) { Reg = State.AllocateReg(IntRegs, IntRegsSize); // If this is the first part of an i64 arg, // the allocated register must be either A0 or A2. if (isI64 && (Reg == Mips::A1 || Reg == Mips::A3)) Reg = State.AllocateReg(IntRegs, IntRegsSize); LocVT = MVT::i32; } else if (ValVT == MVT::f64 && AllocateFloatsInIntReg) { // Allocate int register and shadow next int register. If first // available register is Mips::A1 or Mips::A3, shadow it too. Reg = State.AllocateReg(IntRegs, IntRegsSize); if (Reg == Mips::A1 || Reg == Mips::A3) Reg = State.AllocateReg(IntRegs, IntRegsSize); State.AllocateReg(IntRegs, IntRegsSize); LocVT = MVT::i32; } else if (ValVT.isFloatingPoint() && !AllocateFloatsInIntReg) { // we are guaranteed to find an available float register if (ValVT == MVT::f32) { Reg = State.AllocateReg(F32Regs, FloatRegsSize); // Shadow int register State.AllocateReg(IntRegs, IntRegsSize); } else { Reg = State.AllocateReg(F64Regs, FloatRegsSize); // Shadow int registers unsigned Reg2 = State.AllocateReg(IntRegs, IntRegsSize); if (Reg2 == Mips::A1 || Reg2 == Mips::A3) State.AllocateReg(IntRegs, IntRegsSize); State.AllocateReg(IntRegs, IntRegsSize); } } else llvm_unreachable("Cannot handle this ValVT."); if (!Reg) { unsigned SizeInBytes = ValVT.getSizeInBits() >> 3; unsigned Offset = State.AllocateStack(SizeInBytes, OrigAlign); State.addLoc(CCValAssign::getMem(ValNo, ValVT, Offset, LocVT, LocInfo)); } else State.addLoc(CCValAssign::getReg(ValNo, ValVT, Reg, LocVT, LocInfo)); return false; // CC must always match } //===----------------------------------------------------------------------===// // Call Calling Convention Implementation //===----------------------------------------------------------------------===// /// LowerCall - functions arguments are copied from virtual regs to /// (physical regs)/(stack frame), CALLSEQ_START and CALLSEQ_END are emitted. /// TODO: isTailCall. SDValue MipsTargetLowering::LowerCall(SDValue Chain, SDValue Callee, CallingConv::ID CallConv, bool isVarArg, bool &isTailCall, const SmallVectorImpl &Outs, const SmallVectorImpl &OutVals, const SmallVectorImpl &Ins, DebugLoc dl, SelectionDAG &DAG, SmallVectorImpl &InVals) const { // MIPs target does not yet support tail call optimization. isTailCall = false; MachineFunction &MF = DAG.getMachineFunction(); MachineFrameInfo *MFI = MF.getFrameInfo(); bool IsPIC = getTargetMachine().getRelocationModel() == Reloc::PIC_; // Analyze operands of the call, assigning locations to each operand. SmallVector ArgLocs; CCState CCInfo(CallConv, isVarArg, getTargetMachine(), ArgLocs, *DAG.getContext()); if (Subtarget->isABI_O32()) { CCInfo.AnalyzeCallOperands(Outs, CC_MipsO32); } else CCInfo.AnalyzeCallOperands(Outs, CC_Mips); // Get a count of how many bytes are to be pushed on the stack. unsigned NumBytes = CCInfo.getNextStackOffset(); Chain = DAG.getCALLSEQ_START(Chain, DAG.getIntPtrConstant(NumBytes, true)); // With EABI is it possible to have 16 args on registers. SmallVector, 16> RegsToPass; SmallVector MemOpChains; // First/LastArgStackLoc contains the first/last // "at stack" argument location. int LastArgStackLoc = 0; unsigned FirstStackArgLoc = (Subtarget->isABI_EABI() ? 0 : 16); // Walk the register/memloc assignments, inserting copies/loads. for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) { SDValue Arg = OutVals[i]; CCValAssign &VA = ArgLocs[i]; // Promote the value if needed. switch (VA.getLocInfo()) { default: llvm_unreachable("Unknown loc info!"); case CCValAssign::Full: if (Subtarget->isABI_O32() && VA.isRegLoc()) { if (VA.getValVT() == MVT::f32 && VA.getLocVT() == MVT::i32) Arg = DAG.getNode(ISD::BITCAST, dl, MVT::i32, Arg); if (VA.getValVT() == MVT::f64 && VA.getLocVT() == MVT::i32) { SDValue Lo = DAG.getNode(MipsISD::ExtractElementF64, dl, MVT::i32, Arg, DAG.getConstant(0, MVT::i32)); SDValue Hi = DAG.getNode(MipsISD::ExtractElementF64, dl, MVT::i32, Arg, DAG.getConstant(1, MVT::i32)); if (!Subtarget->isLittle()) std::swap(Lo, Hi); RegsToPass.push_back(std::make_pair(VA.getLocReg(), Lo)); RegsToPass.push_back(std::make_pair(VA.getLocReg()+1, Hi)); continue; } } 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)); continue; } // Register can't get to this point... assert(VA.isMemLoc()); // Create the frame index object for this incoming parameter // This guarantees that when allocating Local Area the firsts // 16 bytes which are alwayes reserved won't be overwritten // if O32 ABI is used. For EABI the first address is zero. LastArgStackLoc = (FirstStackArgLoc + VA.getLocMemOffset()); int FI = MFI->CreateFixedObject(VA.getValVT().getSizeInBits()/8, LastArgStackLoc, true); SDValue PtrOff = DAG.getFrameIndex(FI,getPointerTy()); // emit ISD::STORE whichs stores the // parameter value to a stack Location MemOpChains.push_back(DAG.getStore(Chain, dl, Arg, PtrOff, MachinePointerInfo(), false, false, 0)); } // 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[0], MemOpChains.size()); // If the callee is a GlobalAddress/ExternalSymbol node (quite common, every // direct call is) turn it into a TargetGlobalAddress/TargetExternalSymbol // node so that legalize doesn't hack it. unsigned char OpFlag = IsPIC ? MipsII::MO_GOT_CALL : MipsII::MO_NO_FLAG; bool LoadSymAddr = false; SDValue CalleeLo; if (GlobalAddressSDNode *G = dyn_cast(Callee)) { if (IsPIC && G->getGlobal()->hasInternalLinkage()) { Callee = DAG.getTargetGlobalAddress(G->getGlobal(), dl, getPointerTy(), 0,MipsII:: MO_GOT); CalleeLo = DAG.getTargetGlobalAddress(G->getGlobal(), dl, getPointerTy(), 0, MipsII::MO_ABS_LO); } else { Callee = DAG.getTargetGlobalAddress(G->getGlobal(), dl, getPointerTy(), 0, OpFlag); } LoadSymAddr = true; } else if (ExternalSymbolSDNode *S = dyn_cast(Callee)) { Callee = DAG.getTargetExternalSymbol(S->getSymbol(), getPointerTy(), OpFlag); LoadSymAddr = true; } SDValue InFlag; // Create nodes that load address of callee and copy it to T9 if (IsPIC) { if (LoadSymAddr) { // Load callee address SDValue LoadValue = DAG.getLoad(MVT::i32, dl, Chain, Callee, MachinePointerInfo::getGOT(), false, false, 0); // Use GOT+LO if callee has internal linkage. if (CalleeLo.getNode()) { SDValue Lo = DAG.getNode(MipsISD::Lo, dl, MVT::i32, CalleeLo); Callee = DAG.getNode(ISD::ADD, dl, MVT::i32, LoadValue, Lo); } else Callee = LoadValue; // Use chain output from LoadValue Chain = LoadValue.getValue(1); } // copy to T9 Chain = DAG.getCopyToReg(Chain, dl, Mips::T9, Callee, SDValue(0, 0)); InFlag = Chain.getValue(1); Callee = DAG.getRegister(Mips::T9, MVT::i32); } // 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. for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i) { Chain = DAG.getCopyToReg(Chain, dl, RegsToPass[i].first, RegsToPass[i].second, InFlag); InFlag = Chain.getValue(1); } // MipsJmpLink = #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 Ops; Ops.push_back(Chain); Ops.push_back(Callee); // Add argument registers to the end of the list so that they are // known live into the call. for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i) Ops.push_back(DAG.getRegister(RegsToPass[i].first, RegsToPass[i].second.getValueType())); if (InFlag.getNode()) Ops.push_back(InFlag); Chain = DAG.getNode(MipsISD::JmpLink, dl, NodeTys, &Ops[0], Ops.size()); InFlag = Chain.getValue(1); // Create a stack location to hold GP when PIC is used. This stack // location is used on function prologue to save GP and also after all // emitted CALL's to restore GP. if (IsPIC) { // Function can have an arbitrary number of calls, so // hold the LastArgStackLoc with the biggest offset. int FI; MipsFunctionInfo *MipsFI = MF.getInfo(); if (LastArgStackLoc >= MipsFI->getGPStackOffset()) { LastArgStackLoc = (!LastArgStackLoc) ? (16) : (LastArgStackLoc+4); // Create the frame index only once. SPOffset here can be anything // (this will be fixed on processFunctionBeforeFrameFinalized) if (MipsFI->getGPStackOffset() == -1) { FI = MFI->CreateFixedObject(4, 0, true); MipsFI->setGPFI(FI); } MipsFI->setGPStackOffset(LastArgStackLoc); } } // Create the CALLSEQ_END node. Chain = DAG.getCALLSEQ_END(Chain, DAG.getIntPtrConstant(NumBytes, true), DAG.getIntPtrConstant(0, true), InFlag); InFlag = Chain.getValue(1); // Handle result values, copying them out of physregs into vregs that we // return. return LowerCallResult(Chain, InFlag, CallConv, isVarArg, Ins, dl, DAG, InVals); } /// LowerCallResult - Lower the result values of a call into the /// appropriate copies out of appropriate physical registers. SDValue MipsTargetLowering::LowerCallResult(SDValue Chain, SDValue InFlag, CallingConv::ID CallConv, bool isVarArg, const SmallVectorImpl &Ins, DebugLoc dl, SelectionDAG &DAG, SmallVectorImpl &InVals) const { // Assign locations to each value returned by this call. SmallVector RVLocs; CCState CCInfo(CallConv, isVarArg, getTargetMachine(), RVLocs, *DAG.getContext()); CCInfo.AnalyzeCallResult(Ins, RetCC_Mips); // Copy all of the result registers out of their specified physreg. for (unsigned i = 0; i != RVLocs.size(); ++i) { Chain = DAG.getCopyFromReg(Chain, dl, RVLocs[i].getLocReg(), RVLocs[i].getValVT(), InFlag).getValue(1); InFlag = Chain.getValue(2); InVals.push_back(Chain.getValue(0)); } return Chain; } //===----------------------------------------------------------------------===// // Formal Arguments Calling Convention Implementation //===----------------------------------------------------------------------===// /// LowerFormalArguments - transform physical registers into virtual registers /// and generate load operations for arguments places on the stack. SDValue MipsTargetLowering::LowerFormalArguments(SDValue Chain, CallingConv::ID CallConv, bool isVarArg, const SmallVectorImpl &Ins, DebugLoc dl, SelectionDAG &DAG, SmallVectorImpl &InVals) const { MachineFunction &MF = DAG.getMachineFunction(); MachineFrameInfo *MFI = MF.getFrameInfo(); MipsFunctionInfo *MipsFI = MF.getInfo(); MipsFI->setVarArgsFrameIndex(0); // Used with vargs to acumulate store chains. std::vector OutChains; // Keep track of the last register used for arguments unsigned ArgRegEnd = 0; // Assign locations to all of the incoming arguments. SmallVector ArgLocs; CCState CCInfo(CallConv, isVarArg, getTargetMachine(), ArgLocs, *DAG.getContext()); if (Subtarget->isABI_O32()) CCInfo.AnalyzeFormalArguments(Ins, CC_MipsO32); else CCInfo.AnalyzeFormalArguments(Ins, CC_Mips); unsigned FirstStackArgLoc = (Subtarget->isABI_EABI() ? 0 : 16); unsigned LastStackArgEndOffset = 0; EVT LastRegArgValVT; for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) { CCValAssign &VA = ArgLocs[i]; // Arguments stored on registers if (VA.isRegLoc()) { EVT RegVT = VA.getLocVT(); ArgRegEnd = VA.getLocReg(); LastRegArgValVT = VA.getValVT(); TargetRegisterClass *RC = 0; if (RegVT == MVT::i32) RC = Mips::CPURegsRegisterClass; else if (RegVT == MVT::f32) RC = Mips::FGR32RegisterClass; else if (RegVT == MVT::f64) { if (!Subtarget->isSingleFloat()) RC = Mips::AFGR64RegisterClass; } else llvm_unreachable("RegVT not supported by FormalArguments Lowering"); // Transform the arguments stored on // physical registers into virtual ones unsigned Reg = AddLiveIn(DAG.getMachineFunction(), ArgRegEnd, RC); SDValue ArgValue = DAG.getCopyFromReg(Chain, dl, Reg, RegVT); // If this is an 8 or 16-bit value, it has been passed promoted // to 32 bits. Insert an assert[sz]ext to capture this, then // truncate to the right size. if (VA.getLocInfo() != CCValAssign::Full) { unsigned Opcode = 0; if (VA.getLocInfo() == CCValAssign::SExt) Opcode = ISD::AssertSext; else if (VA.getLocInfo() == CCValAssign::ZExt) Opcode = ISD::AssertZext; if (Opcode) ArgValue = DAG.getNode(Opcode, dl, RegVT, ArgValue, DAG.getValueType(VA.getValVT())); ArgValue = DAG.getNode(ISD::TRUNCATE, dl, VA.getValVT(), ArgValue); } // Handle O32 ABI cases: i32->f32 and (i32,i32)->f64 if (Subtarget->isABI_O32()) { if (RegVT == MVT::i32 && VA.getValVT() == MVT::f32) ArgValue = DAG.getNode(ISD::BITCAST, dl, MVT::f32, ArgValue); if (RegVT == MVT::i32 && VA.getValVT() == MVT::f64) { unsigned Reg2 = AddLiveIn(DAG.getMachineFunction(), VA.getLocReg()+1, RC); SDValue ArgValue2 = DAG.getCopyFromReg(Chain, dl, Reg2, RegVT); if (!Subtarget->isLittle()) std::swap(ArgValue, ArgValue2); ArgValue = DAG.getNode(MipsISD::BuildPairF64, dl, MVT::f64, ArgValue, ArgValue2); } } InVals.push_back(ArgValue); } else { // VA.isRegLoc() // sanity check assert(VA.isMemLoc()); // The last argument is not a register anymore ArgRegEnd = 0; // The stack pointer offset is relative to the caller stack frame. // Since the real stack size is unknown here, a negative SPOffset // is used so there's a way to adjust these offsets when the stack // size get known (on EliminateFrameIndex). A dummy SPOffset is // used instead of a direct negative address (which is recorded to // be used on emitPrologue) to avoid mis-calc of the first stack // offset on PEI::calculateFrameObjectOffsets. unsigned ArgSize = VA.getValVT().getSizeInBits()/8; LastStackArgEndOffset = FirstStackArgLoc + VA.getLocMemOffset() + ArgSize; int FI = MFI->CreateFixedObject(ArgSize, 0, true); MipsFI->recordLoadArgsFI(FI, -(4 + (FirstStackArgLoc + VA.getLocMemOffset()))); // Create load nodes to retrieve arguments from the stack SDValue FIN = DAG.getFrameIndex(FI, getPointerTy()); InVals.push_back(DAG.getLoad(VA.getValVT(), dl, Chain, FIN, MachinePointerInfo::getFixedStack(FI), false, false, 0)); } } // The mips ABIs for returning structs by value requires that we copy // the sret argument into $v0 for the return. Save the argument into // a virtual register so that we can access it from the return points. if (DAG.getMachineFunction().getFunction()->hasStructRetAttr()) { unsigned Reg = MipsFI->getSRetReturnReg(); if (!Reg) { Reg = MF.getRegInfo().createVirtualRegister(getRegClassFor(MVT::i32)); MipsFI->setSRetReturnReg(Reg); } SDValue Copy = DAG.getCopyToReg(DAG.getEntryNode(), dl, Reg, InVals[0]); Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, Copy, Chain); } // To meet ABI, when VARARGS are passed on registers, the registers // must have their values written to the caller stack frame. If the last // argument was placed in the stack, there's no need to save any register. if (isVarArg && Subtarget->isABI_O32()) { if (ArgRegEnd) { // Last named formal argument is passed in register. // The last register argument that must be saved is Mips::A3 TargetRegisterClass *RC = Mips::CPURegsRegisterClass; if (LastRegArgValVT == MVT::f64) ArgRegEnd++; if (ArgRegEnd < Mips::A3) { // Both the last named formal argument and the first variable // argument are passed in registers. for (++ArgRegEnd; ArgRegEnd <= Mips::A3; ++ArgRegEnd) { unsigned Reg = AddLiveIn(DAG.getMachineFunction(), ArgRegEnd, RC); SDValue ArgValue = DAG.getCopyFromReg(Chain, dl, Reg, MVT::i32); int FI = MFI->CreateFixedObject(4, 0, true); MipsFI->recordStoreVarArgsFI(FI, -(4+(ArgRegEnd-Mips::A0)*4)); SDValue PtrOff = DAG.getFrameIndex(FI, getPointerTy()); OutChains.push_back(DAG.getStore(Chain, dl, ArgValue, PtrOff, MachinePointerInfo(), false, false, 0)); // Record the frame index of the first variable argument // which is a value necessary to VASTART. if (!MipsFI->getVarArgsFrameIndex()) { MFI->setObjectAlignment(FI, 4); MipsFI->setVarArgsFrameIndex(FI); } } } else { // Last named formal argument is in register Mips::A3, and the first // variable argument is on stack. Record the frame index of the first // variable argument. int FI = MFI->CreateFixedObject(4, 0, true); MFI->setObjectAlignment(FI, 4); MipsFI->recordStoreVarArgsFI(FI, -20); MipsFI->setVarArgsFrameIndex(FI); } } else { // Last named formal argument and all the variable arguments are passed // on stack. Record the frame index of the first variable argument. int FI = MFI->CreateFixedObject(4, 0, true); MFI->setObjectAlignment(FI, 4); MipsFI->recordStoreVarArgsFI(FI, -(4+LastStackArgEndOffset)); MipsFI->setVarArgsFrameIndex(FI); } } // All stores are grouped in one node to allow the matching between // the size of Ins and InVals. This only happens when on varg functions if (!OutChains.empty()) { OutChains.push_back(Chain); Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, &OutChains[0], OutChains.size()); } return Chain; } //===----------------------------------------------------------------------===// // Return Value Calling Convention Implementation //===----------------------------------------------------------------------===// SDValue MipsTargetLowering::LowerReturn(SDValue Chain, CallingConv::ID CallConv, bool isVarArg, const SmallVectorImpl &Outs, const SmallVectorImpl &OutVals, DebugLoc dl, SelectionDAG &DAG) const { // CCValAssign - represent the assignment of // the return value to a location SmallVector RVLocs; // CCState - Info about the registers and stack slot. CCState CCInfo(CallConv, isVarArg, getTargetMachine(), RVLocs, *DAG.getContext()); // Analize return values. CCInfo.AnalyzeReturn(Outs, RetCC_Mips); // If this is the first return lowered for this function, add // the regs to the liveout set for the function. if (DAG.getMachineFunction().getRegInfo().liveout_empty()) { for (unsigned i = 0; i != RVLocs.size(); ++i) if (RVLocs[i].isRegLoc()) DAG.getMachineFunction().getRegInfo().addLiveOut(RVLocs[i].getLocReg()); } SDValue Flag; // Copy the result values into the output registers. for (unsigned i = 0; i != RVLocs.size(); ++i) { CCValAssign &VA = RVLocs[i]; assert(VA.isRegLoc() && "Can only return in 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); } // The mips ABIs for returning structs by value requires that we copy // the sret argument into $v0 for the return. We saved the argument into // a virtual register in the entry block, so now we copy the value out // and into $v0. if (DAG.getMachineFunction().getFunction()->hasStructRetAttr()) { MachineFunction &MF = DAG.getMachineFunction(); MipsFunctionInfo *MipsFI = MF.getInfo(); unsigned Reg = MipsFI->getSRetReturnReg(); if (!Reg) llvm_unreachable("sret virtual register not created in the entry block"); SDValue Val = DAG.getCopyFromReg(Chain, dl, Reg, getPointerTy()); Chain = DAG.getCopyToReg(Chain, dl, Mips::V0, Val, Flag); Flag = Chain.getValue(1); } // Return on Mips is always a "jr $ra" if (Flag.getNode()) return DAG.getNode(MipsISD::Ret, dl, MVT::Other, Chain, DAG.getRegister(Mips::RA, MVT::i32), Flag); else // Return Void return DAG.getNode(MipsISD::Ret, dl, MVT::Other, Chain, DAG.getRegister(Mips::RA, MVT::i32)); } //===----------------------------------------------------------------------===// // Mips Inline Assembly Support //===----------------------------------------------------------------------===// /// getConstraintType - Given a constraint letter, return the type of /// constraint it is for this target. MipsTargetLowering::ConstraintType MipsTargetLowering:: getConstraintType(const std::string &Constraint) const { // Mips specific constrainy // GCC config/mips/constraints.md // // 'd' : An address register. Equivalent to r // unless generating MIPS16 code. // 'y' : Equivalent to r; retained for // backwards compatibility. // 'f' : Floating Point registers. if (Constraint.size() == 1) { switch (Constraint[0]) { default : break; case 'd': case 'y': case 'f': return C_RegisterClass; break; } } return TargetLowering::getConstraintType(Constraint); } /// Examine constraint type and operand type and determine a weight value. /// This object must already have been set up with the operand type /// and the current alternative constraint selected. TargetLowering::ConstraintWeight MipsTargetLowering::getSingleConstraintMatchWeight( AsmOperandInfo &info, const char *constraint) const { ConstraintWeight weight = CW_Invalid; Value *CallOperandVal = info.CallOperandVal; // If we don't have a value, we can't do a match, // but allow it at the lowest weight. if (CallOperandVal == NULL) return CW_Default; const Type *type = CallOperandVal->getType(); // Look at the constraint type. switch (*constraint) { default: weight = TargetLowering::getSingleConstraintMatchWeight(info, constraint); break; case 'd': case 'y': if (type->isIntegerTy()) weight = CW_Register; break; case 'f': if (type->isFloatTy()) weight = CW_Register; break; } return weight; } /// getRegClassForInlineAsmConstraint - Given a constraint letter (e.g. "r"), /// return a list of registers that can be used to satisfy the constraint. /// This should only be used for C_RegisterClass constraints. std::pair MipsTargetLowering:: getRegForInlineAsmConstraint(const std::string &Constraint, EVT VT) const { if (Constraint.size() == 1) { switch (Constraint[0]) { case 'r': return std::make_pair(0U, Mips::CPURegsRegisterClass); case 'f': if (VT == MVT::f32) return std::make_pair(0U, Mips::FGR32RegisterClass); if (VT == MVT::f64) if ((!Subtarget->isSingleFloat()) && (!Subtarget->isFP64bit())) return std::make_pair(0U, Mips::AFGR64RegisterClass); } } return TargetLowering::getRegForInlineAsmConstraint(Constraint, VT); } /// Given a register class constraint, like 'r', if this corresponds directly /// to an LLVM register class, return a register of 0 and the register class /// pointer. std::vector MipsTargetLowering:: getRegClassForInlineAsmConstraint(const std::string &Constraint, EVT VT) const { if (Constraint.size() != 1) return std::vector(); switch (Constraint[0]) { default : break; case 'r': // GCC Mips Constraint Letters case 'd': case 'y': return make_vector(Mips::T0, Mips::T1, Mips::T2, Mips::T3, Mips::T4, Mips::T5, Mips::T6, Mips::T7, Mips::S0, Mips::S1, Mips::S2, Mips::S3, Mips::S4, Mips::S5, Mips::S6, Mips::S7, Mips::T8, 0); case 'f': if (VT == MVT::f32) { if (Subtarget->isSingleFloat()) return make_vector(Mips::F2, Mips::F3, Mips::F4, Mips::F5, Mips::F6, Mips::F7, Mips::F8, Mips::F9, Mips::F10, Mips::F11, Mips::F20, Mips::F21, Mips::F22, Mips::F23, Mips::F24, Mips::F25, Mips::F26, Mips::F27, Mips::F28, Mips::F29, Mips::F30, Mips::F31, 0); else return make_vector(Mips::F2, Mips::F4, Mips::F6, Mips::F8, Mips::F10, Mips::F20, Mips::F22, Mips::F24, Mips::F26, Mips::F28, Mips::F30, 0); } if (VT == MVT::f64) if ((!Subtarget->isSingleFloat()) && (!Subtarget->isFP64bit())) return make_vector(Mips::D1, Mips::D2, Mips::D3, Mips::D4, Mips::D5, Mips::D10, Mips::D11, Mips::D12, Mips::D13, Mips::D14, Mips::D15, 0); } return std::vector(); } bool MipsTargetLowering::isOffsetFoldingLegal(const GlobalAddressSDNode *GA) const { // The Mips target isn't yet aware of offsets. return false; } bool MipsTargetLowering::isFPImmLegal(const APFloat &Imm, EVT VT) const { if (VT != MVT::f32 && VT != MVT::f64) return false; if (Imm.isNegZero()) return false; return Imm.isZero(); }