//===-- MipsastISel.cpp - Mips FastISel implementation //---------------------===// #include "llvm/CodeGen/FunctionLoweringInfo.h" #include "MipsCCState.h" #include "MipsISelLowering.h" #include "MipsMachineFunction.h" #include "MipsRegisterInfo.h" #include "MipsSubtarget.h" #include "MipsTargetMachine.h" #include "llvm/Analysis/TargetLibraryInfo.h" #include "llvm/CodeGen/FastISel.h" #include "llvm/CodeGen/MachineInstrBuilder.h" #include "llvm/IR/GlobalAlias.h" #include "llvm/IR/GlobalVariable.h" #include "llvm/Target/TargetInstrInfo.h" using namespace llvm; namespace { class MipsFastISel final : public FastISel { // All possible address modes. class Address { public: typedef enum { RegBase, FrameIndexBase } BaseKind; private: BaseKind Kind; union { unsigned Reg; int FI; } Base; int64_t Offset; const GlobalValue *GV; public: // Innocuous defaults for our address. Address() : Kind(RegBase), Offset(0), GV(0) { Base.Reg = 0; } void setKind(BaseKind K) { Kind = K; } BaseKind getKind() const { return Kind; } bool isRegBase() const { return Kind == RegBase; } void setReg(unsigned Reg) { assert(isRegBase() && "Invalid base register access!"); Base.Reg = Reg; } unsigned getReg() const { assert(isRegBase() && "Invalid base register access!"); return Base.Reg; } void setOffset(int64_t Offset_) { Offset = Offset_; } int64_t getOffset() const { return Offset; } void setGlobalValue(const GlobalValue *G) { GV = G; } const GlobalValue *getGlobalValue() { return GV; } }; /// Subtarget - Keep a pointer to the MipsSubtarget around so that we can /// make the right decision when generating code for different targets. const TargetMachine &TM; const MipsSubtarget *Subtarget; const TargetInstrInfo &TII; const TargetLowering &TLI; MipsFunctionInfo *MFI; // Convenience variables to avoid some queries. LLVMContext *Context; bool fastLowerCall(CallLoweringInfo &CLI) override; bool TargetSupported; bool UnsupportedFPMode; // To allow fast-isel to proceed and just not handle // floating point but not reject doing fast-isel in other // situations private: // Selection routines. bool selectLoad(const Instruction *I); bool selectStore(const Instruction *I); bool selectBranch(const Instruction *I); bool selectCmp(const Instruction *I); bool selectFPExt(const Instruction *I); bool selectFPTrunc(const Instruction *I); bool selectFPToInt(const Instruction *I, bool IsSigned); bool selectRet(const Instruction *I); bool selectTrunc(const Instruction *I); bool selectIntExt(const Instruction *I); // Utility helper routines. bool isTypeLegal(Type *Ty, MVT &VT); bool isLoadTypeLegal(Type *Ty, MVT &VT); bool computeAddress(const Value *Obj, Address &Addr); bool computeCallAddress(const Value *V, Address &Addr); // Emit helper routines. bool emitCmp(unsigned DestReg, const CmpInst *CI); bool emitLoad(MVT VT, unsigned &ResultReg, Address &Addr, unsigned Alignment = 0); bool emitStore(MVT VT, unsigned SrcReg, Address Addr, MachineMemOperand *MMO = nullptr); bool emitStore(MVT VT, unsigned SrcReg, Address &Addr, unsigned Alignment = 0); unsigned emitIntExt(MVT SrcVT, unsigned SrcReg, MVT DestVT, bool isZExt); bool emitIntExt(MVT SrcVT, unsigned SrcReg, MVT DestVT, unsigned DestReg, bool IsZExt); bool emitIntZExt(MVT SrcVT, unsigned SrcReg, MVT DestVT, unsigned DestReg); bool emitIntSExt(MVT SrcVT, unsigned SrcReg, MVT DestVT, unsigned DestReg); bool emitIntSExt32r1(MVT SrcVT, unsigned SrcReg, MVT DestVT, unsigned DestReg); bool emitIntSExt32r2(MVT SrcVT, unsigned SrcReg, MVT DestVT, unsigned DestReg); unsigned getRegEnsuringSimpleIntegerWidening(const Value *, bool IsUnsigned); unsigned materializeFP(const ConstantFP *CFP, MVT VT); unsigned materializeGV(const GlobalValue *GV, MVT VT); unsigned materializeInt(const Constant *C, MVT VT); unsigned materialize32BitInt(int64_t Imm, const TargetRegisterClass *RC); MachineInstrBuilder emitInst(unsigned Opc) { return BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(Opc)); } MachineInstrBuilder emitInst(unsigned Opc, unsigned DstReg) { return BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(Opc), DstReg); } MachineInstrBuilder emitInstStore(unsigned Opc, unsigned SrcReg, unsigned MemReg, int64_t MemOffset) { return emitInst(Opc).addReg(SrcReg).addReg(MemReg).addImm(MemOffset); } MachineInstrBuilder emitInstLoad(unsigned Opc, unsigned DstReg, unsigned MemReg, int64_t MemOffset) { return emitInst(Opc, DstReg).addReg(MemReg).addImm(MemOffset); } // for some reason, this default is not generated by tablegen // so we explicitly generate it here. // unsigned fastEmitInst_riir(uint64_t inst, const TargetRegisterClass *RC, unsigned Op0, bool Op0IsKill, uint64_t imm1, uint64_t imm2, unsigned Op3, bool Op3IsKill) { return 0; } // Call handling routines. private: CCAssignFn *CCAssignFnForCall(CallingConv::ID CC) const; bool processCallArgs(CallLoweringInfo &CLI, SmallVectorImpl &ArgVTs, unsigned &NumBytes); bool finishCall(CallLoweringInfo &CLI, MVT RetVT, unsigned NumBytes); public: // Backend specific FastISel code. explicit MipsFastISel(FunctionLoweringInfo &funcInfo, const TargetLibraryInfo *libInfo) : FastISel(funcInfo, libInfo), TM(funcInfo.MF->getTarget()), Subtarget( &static_cast(funcInfo.MF->getSubtarget())), TII(*Subtarget->getInstrInfo()), TLI(*Subtarget->getTargetLowering()) { MFI = funcInfo.MF->getInfo(); Context = &funcInfo.Fn->getContext(); TargetSupported = ((TM.getRelocationModel() == Reloc::PIC_) && ((Subtarget->hasMips32r2() || Subtarget->hasMips32()) && (static_cast(TM).getABI().IsO32()))); UnsupportedFPMode = Subtarget->isFP64bit(); } unsigned fastMaterializeConstant(const Constant *C) override; bool fastSelectInstruction(const Instruction *I) override; #include "MipsGenFastISel.inc" }; } // end anonymous namespace. static bool CC_Mips(unsigned ValNo, MVT ValVT, MVT LocVT, CCValAssign::LocInfo LocInfo, ISD::ArgFlagsTy ArgFlags, CCState &State) LLVM_ATTRIBUTE_UNUSED; static bool CC_MipsO32_FP32(unsigned ValNo, MVT ValVT, MVT LocVT, CCValAssign::LocInfo LocInfo, ISD::ArgFlagsTy ArgFlags, CCState &State) { llvm_unreachable("should not be called"); } bool CC_MipsO32_FP64(unsigned ValNo, MVT ValVT, MVT LocVT, CCValAssign::LocInfo LocInfo, ISD::ArgFlagsTy ArgFlags, CCState &State) { llvm_unreachable("should not be called"); } #include "MipsGenCallingConv.inc" CCAssignFn *MipsFastISel::CCAssignFnForCall(CallingConv::ID CC) const { return CC_MipsO32; } unsigned MipsFastISel::materializeInt(const Constant *C, MVT VT) { if (VT != MVT::i32 && VT != MVT::i16 && VT != MVT::i8 && VT != MVT::i1) return 0; const TargetRegisterClass *RC = &Mips::GPR32RegClass; const ConstantInt *CI = cast(C); int64_t Imm; if ((VT != MVT::i1) && CI->isNegative()) Imm = CI->getSExtValue(); else Imm = CI->getZExtValue(); return materialize32BitInt(Imm, RC); } unsigned MipsFastISel::materialize32BitInt(int64_t Imm, const TargetRegisterClass *RC) { unsigned ResultReg = createResultReg(RC); if (isInt<16>(Imm)) { unsigned Opc = Mips::ADDiu; emitInst(Opc, ResultReg).addReg(Mips::ZERO).addImm(Imm); return ResultReg; } else if (isUInt<16>(Imm)) { emitInst(Mips::ORi, ResultReg).addReg(Mips::ZERO).addImm(Imm); return ResultReg; } unsigned Lo = Imm & 0xFFFF; unsigned Hi = (Imm >> 16) & 0xFFFF; if (Lo) { // Both Lo and Hi have nonzero bits. unsigned TmpReg = createResultReg(RC); emitInst(Mips::LUi, TmpReg).addImm(Hi); emitInst(Mips::ORi, ResultReg).addReg(TmpReg).addImm(Lo); } else { emitInst(Mips::LUi, ResultReg).addImm(Hi); } return ResultReg; } unsigned MipsFastISel::materializeFP(const ConstantFP *CFP, MVT VT) { if (UnsupportedFPMode) return 0; int64_t Imm = CFP->getValueAPF().bitcastToAPInt().getZExtValue(); if (VT == MVT::f32) { const TargetRegisterClass *RC = &Mips::FGR32RegClass; unsigned DestReg = createResultReg(RC); unsigned TempReg = materialize32BitInt(Imm, &Mips::GPR32RegClass); emitInst(Mips::MTC1, DestReg).addReg(TempReg); return DestReg; } else if (VT == MVT::f64) { const TargetRegisterClass *RC = &Mips::AFGR64RegClass; unsigned DestReg = createResultReg(RC); unsigned TempReg1 = materialize32BitInt(Imm >> 32, &Mips::GPR32RegClass); unsigned TempReg2 = materialize32BitInt(Imm & 0xFFFFFFFF, &Mips::GPR32RegClass); emitInst(Mips::BuildPairF64, DestReg).addReg(TempReg2).addReg(TempReg1); return DestReg; } return 0; } unsigned MipsFastISel::materializeGV(const GlobalValue *GV, MVT VT) { // For now 32-bit only. if (VT != MVT::i32) return 0; const TargetRegisterClass *RC = &Mips::GPR32RegClass; unsigned DestReg = createResultReg(RC); const GlobalVariable *GVar = dyn_cast(GV); bool IsThreadLocal = GVar && GVar->isThreadLocal(); // TLS not supported at this time. if (IsThreadLocal) return 0; emitInst(Mips::LW, DestReg) .addReg(MFI->getGlobalBaseReg()) .addGlobalAddress(GV, 0, MipsII::MO_GOT); if ((GV->hasInternalLinkage() || (GV->hasLocalLinkage() && !isa(GV)))) { unsigned TempReg = createResultReg(RC); emitInst(Mips::ADDiu, TempReg) .addReg(DestReg) .addGlobalAddress(GV, 0, MipsII::MO_ABS_LO); DestReg = TempReg; } return DestReg; } // Materialize a constant into a register, and return the register // number (or zero if we failed to handle it). unsigned MipsFastISel::fastMaterializeConstant(const Constant *C) { EVT CEVT = TLI.getValueType(C->getType(), true); // Only handle simple types. if (!CEVT.isSimple()) return 0; MVT VT = CEVT.getSimpleVT(); if (const ConstantFP *CFP = dyn_cast(C)) return (UnsupportedFPMode) ? 0 : materializeFP(CFP, VT); else if (const GlobalValue *GV = dyn_cast(C)) return materializeGV(GV, VT); else if (isa(C)) return materializeInt(C, VT); return 0; } bool MipsFastISel::computeAddress(const Value *Obj, Address &Addr) { // This construct looks a big awkward but it is how other ports handle this // and as this function is more fully completed, these cases which // return false will have additional code in them. // if (isa(Obj)) return false; else if (isa(Obj)) return false; Addr.setReg(getRegForValue(Obj)); return Addr.getReg() != 0; } bool MipsFastISel::computeCallAddress(const Value *V, Address &Addr) { const GlobalValue *GV = dyn_cast(V); if (GV && isa(GV) && dyn_cast(GV)->isIntrinsic()) return false; if (!GV) return false; if (const GlobalValue *GV = dyn_cast(V)) { Addr.setGlobalValue(GV); return true; } return false; } bool MipsFastISel::isTypeLegal(Type *Ty, MVT &VT) { EVT evt = TLI.getValueType(Ty, true); // Only handle simple types. if (evt == MVT::Other || !evt.isSimple()) return false; VT = evt.getSimpleVT(); // Handle all legal types, i.e. a register that will directly hold this // value. return TLI.isTypeLegal(VT); } bool MipsFastISel::isLoadTypeLegal(Type *Ty, MVT &VT) { if (isTypeLegal(Ty, VT)) return true; // We will extend this in a later patch: // If this is a type than can be sign or zero-extended to a basic operation // go ahead and accept it now. if (VT == MVT::i8 || VT == MVT::i16) return true; return false; } // Because of how EmitCmp is called with fast-isel, you can // end up with redundant "andi" instructions after the sequences emitted below. // We should try and solve this issue in the future. // bool MipsFastISel::emitCmp(unsigned ResultReg, const CmpInst *CI) { const Value *Left = CI->getOperand(0), *Right = CI->getOperand(1); bool IsUnsigned = CI->isUnsigned(); unsigned LeftReg = getRegEnsuringSimpleIntegerWidening(Left, IsUnsigned); if (LeftReg == 0) return false; unsigned RightReg = getRegEnsuringSimpleIntegerWidening(Right, IsUnsigned); if (RightReg == 0) return false; CmpInst::Predicate P = CI->getPredicate(); switch (P) { default: return false; case CmpInst::ICMP_EQ: { unsigned TempReg = createResultReg(&Mips::GPR32RegClass); emitInst(Mips::XOR, TempReg).addReg(LeftReg).addReg(RightReg); emitInst(Mips::SLTiu, ResultReg).addReg(TempReg).addImm(1); break; } case CmpInst::ICMP_NE: { unsigned TempReg = createResultReg(&Mips::GPR32RegClass); emitInst(Mips::XOR, TempReg).addReg(LeftReg).addReg(RightReg); emitInst(Mips::SLTu, ResultReg).addReg(Mips::ZERO).addReg(TempReg); break; } case CmpInst::ICMP_UGT: { emitInst(Mips::SLTu, ResultReg).addReg(RightReg).addReg(LeftReg); break; } case CmpInst::ICMP_ULT: { emitInst(Mips::SLTu, ResultReg).addReg(LeftReg).addReg(RightReg); break; } case CmpInst::ICMP_UGE: { unsigned TempReg = createResultReg(&Mips::GPR32RegClass); emitInst(Mips::SLTu, TempReg).addReg(LeftReg).addReg(RightReg); emitInst(Mips::XORi, ResultReg).addReg(TempReg).addImm(1); break; } case CmpInst::ICMP_ULE: { unsigned TempReg = createResultReg(&Mips::GPR32RegClass); emitInst(Mips::SLTu, TempReg).addReg(RightReg).addReg(LeftReg); emitInst(Mips::XORi, ResultReg).addReg(TempReg).addImm(1); break; } case CmpInst::ICMP_SGT: { emitInst(Mips::SLT, ResultReg).addReg(RightReg).addReg(LeftReg); break; } case CmpInst::ICMP_SLT: { emitInst(Mips::SLT, ResultReg).addReg(LeftReg).addReg(RightReg); break; } case CmpInst::ICMP_SGE: { unsigned TempReg = createResultReg(&Mips::GPR32RegClass); emitInst(Mips::SLT, TempReg).addReg(LeftReg).addReg(RightReg); emitInst(Mips::XORi, ResultReg).addReg(TempReg).addImm(1); break; } case CmpInst::ICMP_SLE: { unsigned TempReg = createResultReg(&Mips::GPR32RegClass); emitInst(Mips::SLT, TempReg).addReg(RightReg).addReg(LeftReg); emitInst(Mips::XORi, ResultReg).addReg(TempReg).addImm(1); break; } case CmpInst::FCMP_OEQ: case CmpInst::FCMP_UNE: case CmpInst::FCMP_OLT: case CmpInst::FCMP_OLE: case CmpInst::FCMP_OGT: case CmpInst::FCMP_OGE: { if (UnsupportedFPMode) return false; bool IsFloat = Left->getType()->isFloatTy(); bool IsDouble = Left->getType()->isDoubleTy(); if (!IsFloat && !IsDouble) return false; unsigned Opc, CondMovOpc; switch (P) { case CmpInst::FCMP_OEQ: Opc = IsFloat ? Mips::C_EQ_S : Mips::C_EQ_D32; CondMovOpc = Mips::MOVT_I; break; case CmpInst::FCMP_UNE: Opc = IsFloat ? Mips::C_EQ_S : Mips::C_EQ_D32; CondMovOpc = Mips::MOVF_I; break; case CmpInst::FCMP_OLT: Opc = IsFloat ? Mips::C_OLT_S : Mips::C_OLT_D32; CondMovOpc = Mips::MOVT_I; break; case CmpInst::FCMP_OLE: Opc = IsFloat ? Mips::C_OLE_S : Mips::C_OLE_D32; CondMovOpc = Mips::MOVT_I; break; case CmpInst::FCMP_OGT: Opc = IsFloat ? Mips::C_ULE_S : Mips::C_ULE_D32; CondMovOpc = Mips::MOVF_I; break; case CmpInst::FCMP_OGE: Opc = IsFloat ? Mips::C_ULT_S : Mips::C_ULT_D32; CondMovOpc = Mips::MOVF_I; break; default: llvm_unreachable("Only switching of a subset of CCs."); } unsigned RegWithZero = createResultReg(&Mips::GPR32RegClass); unsigned RegWithOne = createResultReg(&Mips::GPR32RegClass); emitInst(Mips::ADDiu, RegWithZero).addReg(Mips::ZERO).addImm(0); emitInst(Mips::ADDiu, RegWithOne).addReg(Mips::ZERO).addImm(1); emitInst(Opc).addReg(LeftReg).addReg(RightReg).addReg( Mips::FCC0, RegState::ImplicitDefine); MachineInstrBuilder MI = emitInst(CondMovOpc, ResultReg) .addReg(RegWithOne) .addReg(Mips::FCC0) .addReg(RegWithZero, RegState::Implicit); MI->tieOperands(0, 3); break; } } return true; } bool MipsFastISel::emitLoad(MVT VT, unsigned &ResultReg, Address &Addr, unsigned Alignment) { // // more cases will be handled here in following patches. // unsigned Opc; switch (VT.SimpleTy) { case MVT::i32: { ResultReg = createResultReg(&Mips::GPR32RegClass); Opc = Mips::LW; break; } case MVT::i16: { ResultReg = createResultReg(&Mips::GPR32RegClass); Opc = Mips::LHu; break; } case MVT::i8: { ResultReg = createResultReg(&Mips::GPR32RegClass); Opc = Mips::LBu; break; } case MVT::f32: { if (UnsupportedFPMode) return false; ResultReg = createResultReg(&Mips::FGR32RegClass); Opc = Mips::LWC1; break; } case MVT::f64: { if (UnsupportedFPMode) return false; ResultReg = createResultReg(&Mips::AFGR64RegClass); Opc = Mips::LDC1; break; } default: return false; } emitInstLoad(Opc, ResultReg, Addr.getReg(), Addr.getOffset()); return true; } bool MipsFastISel::emitStore(MVT VT, unsigned SrcReg, Address &Addr, unsigned Alignment) { // // more cases will be handled here in following patches. // unsigned Opc; switch (VT.SimpleTy) { case MVT::i8: Opc = Mips::SB; break; case MVT::i16: Opc = Mips::SH; break; case MVT::i32: Opc = Mips::SW; break; case MVT::f32: if (UnsupportedFPMode) return false; Opc = Mips::SWC1; break; case MVT::f64: if (UnsupportedFPMode) return false; Opc = Mips::SDC1; break; default: return false; } emitInstStore(Opc, SrcReg, Addr.getReg(), Addr.getOffset()); return true; } bool MipsFastISel::selectLoad(const Instruction *I) { // Atomic loads need special handling. if (cast(I)->isAtomic()) return false; // Verify we have a legal type before going any further. MVT VT; if (!isLoadTypeLegal(I->getType(), VT)) return false; // See if we can handle this address. Address Addr; if (!computeAddress(I->getOperand(0), Addr)) return false; unsigned ResultReg; if (!emitLoad(VT, ResultReg, Addr, cast(I)->getAlignment())) return false; updateValueMap(I, ResultReg); return true; } bool MipsFastISel::selectStore(const Instruction *I) { Value *Op0 = I->getOperand(0); unsigned SrcReg = 0; // Atomic stores need special handling. if (cast(I)->isAtomic()) return false; // Verify we have a legal type before going any further. MVT VT; if (!isLoadTypeLegal(I->getOperand(0)->getType(), VT)) return false; // Get the value to be stored into a register. SrcReg = getRegForValue(Op0); if (SrcReg == 0) return false; // See if we can handle this address. Address Addr; if (!computeAddress(I->getOperand(1), Addr)) return false; if (!emitStore(VT, SrcReg, Addr, cast(I)->getAlignment())) return false; return true; } // // This can cause a redundant sltiu to be generated. // FIXME: try and eliminate this in a future patch. // bool MipsFastISel::selectBranch(const Instruction *I) { const BranchInst *BI = cast(I); MachineBasicBlock *BrBB = FuncInfo.MBB; // // TBB is the basic block for the case where the comparison is true. // FBB is the basic block for the case where the comparison is false. // if (cond) goto TBB // goto FBB // TBB: // MachineBasicBlock *TBB = FuncInfo.MBBMap[BI->getSuccessor(0)]; MachineBasicBlock *FBB = FuncInfo.MBBMap[BI->getSuccessor(1)]; BI->getCondition(); // For now, just try the simplest case where it's fed by a compare. if (const CmpInst *CI = dyn_cast(BI->getCondition())) { unsigned CondReg = createResultReg(&Mips::GPR32RegClass); if (!emitCmp(CondReg, CI)) return false; BuildMI(*BrBB, FuncInfo.InsertPt, DbgLoc, TII.get(Mips::BGTZ)) .addReg(CondReg) .addMBB(TBB); fastEmitBranch(FBB, DbgLoc); FuncInfo.MBB->addSuccessor(TBB); return true; } return false; } bool MipsFastISel::selectCmp(const Instruction *I) { const CmpInst *CI = cast(I); unsigned ResultReg = createResultReg(&Mips::GPR32RegClass); if (!emitCmp(ResultReg, CI)) return false; updateValueMap(I, ResultReg); return true; } // Attempt to fast-select a floating-point extend instruction. bool MipsFastISel::selectFPExt(const Instruction *I) { if (UnsupportedFPMode) return false; Value *Src = I->getOperand(0); EVT SrcVT = TLI.getValueType(Src->getType(), true); EVT DestVT = TLI.getValueType(I->getType(), true); if (SrcVT != MVT::f32 || DestVT != MVT::f64) return false; unsigned SrcReg = getRegForValue(Src); // his must be a 32 bit floating point register class // maybe we should handle this differently if (!SrcReg) return false; unsigned DestReg = createResultReg(&Mips::AFGR64RegClass); emitInst(Mips::CVT_D32_S, DestReg).addReg(SrcReg); updateValueMap(I, DestReg); return true; } // Attempt to fast-select a floating-point truncate instruction. bool MipsFastISel::selectFPTrunc(const Instruction *I) { if (UnsupportedFPMode) return false; Value *Src = I->getOperand(0); EVT SrcVT = TLI.getValueType(Src->getType(), true); EVT DestVT = TLI.getValueType(I->getType(), true); if (SrcVT != MVT::f64 || DestVT != MVT::f32) return false; unsigned SrcReg = getRegForValue(Src); if (!SrcReg) return false; unsigned DestReg = createResultReg(&Mips::FGR32RegClass); if (!DestReg) return false; emitInst(Mips::CVT_S_D32, DestReg).addReg(SrcReg); updateValueMap(I, DestReg); return true; } // Attempt to fast-select a floating-point-to-integer conversion. bool MipsFastISel::selectFPToInt(const Instruction *I, bool IsSigned) { if (UnsupportedFPMode) return false; MVT DstVT, SrcVT; if (!IsSigned) return false; // We don't handle this case yet. There is no native // instruction for this but it can be synthesized. Type *DstTy = I->getType(); if (!isTypeLegal(DstTy, DstVT)) return false; if (DstVT != MVT::i32) return false; Value *Src = I->getOperand(0); Type *SrcTy = Src->getType(); if (!isTypeLegal(SrcTy, SrcVT)) return false; if (SrcVT != MVT::f32 && SrcVT != MVT::f64) return false; unsigned SrcReg = getRegForValue(Src); if (SrcReg == 0) return false; // Determine the opcode for the conversion, which takes place // entirely within FPRs. unsigned DestReg = createResultReg(&Mips::GPR32RegClass); unsigned TempReg = createResultReg(&Mips::FGR32RegClass); unsigned Opc; if (SrcVT == MVT::f32) Opc = Mips::TRUNC_W_S; else Opc = Mips::TRUNC_W_D32; // Generate the convert. emitInst(Opc, TempReg).addReg(SrcReg); emitInst(Mips::MFC1, DestReg).addReg(TempReg); updateValueMap(I, DestReg); return true; } // bool MipsFastISel::processCallArgs(CallLoweringInfo &CLI, SmallVectorImpl &OutVTs, unsigned &NumBytes) { CallingConv::ID CC = CLI.CallConv; SmallVector ArgLocs; CCState CCInfo(CC, false, *FuncInfo.MF, ArgLocs, *Context); CCInfo.AnalyzeCallOperands(OutVTs, CLI.OutFlags, CCAssignFnForCall(CC)); // Get a count of how many bytes are to be pushed on the stack. NumBytes = CCInfo.getNextStackOffset(); // This is the minimum argument area used for A0-A3. if (NumBytes < 16) NumBytes = 16; emitInst(Mips::ADJCALLSTACKDOWN).addImm(16); // Process the args. MVT firstMVT; for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) { CCValAssign &VA = ArgLocs[i]; const Value *ArgVal = CLI.OutVals[VA.getValNo()]; MVT ArgVT = OutVTs[VA.getValNo()]; if (i == 0) { firstMVT = ArgVT; if (ArgVT == MVT::f32) { VA.convertToReg(Mips::F12); } else if (ArgVT == MVT::f64) { VA.convertToReg(Mips::D6); } } else if (i == 1) { if ((firstMVT == MVT::f32) || (firstMVT == MVT::f64)) { if (ArgVT == MVT::f32) { VA.convertToReg(Mips::F14); } else if (ArgVT == MVT::f64) { VA.convertToReg(Mips::D7); } } } if (((ArgVT == MVT::i32) || (ArgVT == MVT::f32)) && VA.isMemLoc()) { switch (VA.getLocMemOffset()) { case 0: VA.convertToReg(Mips::A0); break; case 4: VA.convertToReg(Mips::A1); break; case 8: VA.convertToReg(Mips::A2); break; case 12: VA.convertToReg(Mips::A3); break; default: break; } } unsigned ArgReg = getRegForValue(ArgVal); if (!ArgReg) return false; // Handle arg promotion: SExt, ZExt, AExt. switch (VA.getLocInfo()) { case CCValAssign::Full: break; case CCValAssign::AExt: case CCValAssign::SExt: { MVT DestVT = VA.getLocVT(); MVT SrcVT = ArgVT; ArgReg = emitIntExt(SrcVT, ArgReg, DestVT, /*isZExt=*/false); if (!ArgReg) return false; break; } case CCValAssign::ZExt: { MVT DestVT = VA.getLocVT(); MVT SrcVT = ArgVT; ArgReg = emitIntExt(SrcVT, ArgReg, DestVT, /*isZExt=*/true); if (!ArgReg) return false; break; } default: llvm_unreachable("Unknown arg promotion!"); } // Now copy/store arg to correct locations. if (VA.isRegLoc() && !VA.needsCustom()) { BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(TargetOpcode::COPY), VA.getLocReg()).addReg(ArgReg); CLI.OutRegs.push_back(VA.getLocReg()); } else if (VA.needsCustom()) { llvm_unreachable("Mips does not use custom args."); return false; } else { // // FIXME: This path will currently return false. It was copied // from the AArch64 port and should be essentially fine for Mips too. // The work to finish up this path will be done in a follow-on patch. // assert(VA.isMemLoc() && "Assuming store on stack."); // Don't emit stores for undef values. if (isa(ArgVal)) continue; // Need to store on the stack. // FIXME: This alignment is incorrect but this path is disabled // for now (will return false). We need to determine the right alignment // based on the normal alignment for the underlying machine type. // unsigned ArgSize = RoundUpToAlignment(ArgVT.getSizeInBits(), 4); unsigned BEAlign = 0; if (ArgSize < 8 && !Subtarget->isLittle()) BEAlign = 8 - ArgSize; Address Addr; Addr.setKind(Address::RegBase); Addr.setReg(Mips::SP); Addr.setOffset(VA.getLocMemOffset() + BEAlign); unsigned Alignment = DL.getABITypeAlignment(ArgVal->getType()); MachineMemOperand *MMO = FuncInfo.MF->getMachineMemOperand( MachinePointerInfo::getStack(Addr.getOffset()), MachineMemOperand::MOStore, ArgVT.getStoreSize(), Alignment); (void)(MMO); // if (!emitStore(ArgVT, ArgReg, Addr, MMO)) return false; // can't store on the stack yet. } } return true; } bool MipsFastISel::finishCall(CallLoweringInfo &CLI, MVT RetVT, unsigned NumBytes) { CallingConv::ID CC = CLI.CallConv; emitInst(Mips::ADJCALLSTACKUP).addImm(16); if (RetVT != MVT::isVoid) { SmallVector RVLocs; CCState CCInfo(CC, false, *FuncInfo.MF, RVLocs, *Context); CCInfo.AnalyzeCallResult(RetVT, RetCC_Mips); // Only handle a single return value. if (RVLocs.size() != 1) return false; // Copy all of the result registers out of their specified physreg. MVT CopyVT = RVLocs[0].getValVT(); // Special handling for extended integers. if (RetVT == MVT::i1 || RetVT == MVT::i8 || RetVT == MVT::i16) CopyVT = MVT::i32; unsigned ResultReg = createResultReg(TLI.getRegClassFor(CopyVT)); BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(TargetOpcode::COPY), ResultReg).addReg(RVLocs[0].getLocReg()); CLI.InRegs.push_back(RVLocs[0].getLocReg()); CLI.ResultReg = ResultReg; CLI.NumResultRegs = 1; } return true; } bool MipsFastISel::fastLowerCall(CallLoweringInfo &CLI) { CallingConv::ID CC = CLI.CallConv; bool IsTailCall = CLI.IsTailCall; bool IsVarArg = CLI.IsVarArg; const Value *Callee = CLI.Callee; // const char *SymName = CLI.SymName; // Allow SelectionDAG isel to handle tail calls. if (IsTailCall) return false; // Let SDISel handle vararg functions. if (IsVarArg) return false; // FIXME: Only handle *simple* calls for now. MVT RetVT; if (CLI.RetTy->isVoidTy()) RetVT = MVT::isVoid; else if (!isTypeLegal(CLI.RetTy, RetVT)) return false; for (auto Flag : CLI.OutFlags) if (Flag.isInReg() || Flag.isSRet() || Flag.isNest() || Flag.isByVal()) return false; // Set up the argument vectors. SmallVector OutVTs; OutVTs.reserve(CLI.OutVals.size()); for (auto *Val : CLI.OutVals) { MVT VT; if (!isTypeLegal(Val->getType(), VT) && !(VT == MVT::i1 || VT == MVT::i8 || VT == MVT::i16)) return false; // We don't handle vector parameters yet. if (VT.isVector() || VT.getSizeInBits() > 64) return false; OutVTs.push_back(VT); } Address Addr; if (!computeCallAddress(Callee, Addr)) return false; // Handle the arguments now that we've gotten them. unsigned NumBytes; if (!processCallArgs(CLI, OutVTs, NumBytes)) return false; // Issue the call. unsigned DestAddress = materializeGV(Addr.getGlobalValue(), MVT::i32); emitInst(TargetOpcode::COPY, Mips::T9).addReg(DestAddress); MachineInstrBuilder MIB = BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DbgLoc, TII.get(Mips::JALR), Mips::RA).addReg(Mips::T9); // Add implicit physical register uses to the call. for (auto Reg : CLI.OutRegs) MIB.addReg(Reg, RegState::Implicit); // Add a register mask with the call-preserved registers. // Proper defs for return values will be added by setPhysRegsDeadExcept(). MIB.addRegMask(TRI.getCallPreservedMask(CC)); CLI.Call = MIB; // Add implicit physical register uses to the call. for (auto Reg : CLI.OutRegs) MIB.addReg(Reg, RegState::Implicit); // Add a register mask with the call-preserved registers. Proper // defs for return values will be added by setPhysRegsDeadExcept(). MIB.addRegMask(TRI.getCallPreservedMask(CC)); CLI.Call = MIB; // Finish off the call including any return values. return finishCall(CLI, RetVT, NumBytes); } bool MipsFastISel::selectRet(const Instruction *I) { const ReturnInst *Ret = cast(I); if (!FuncInfo.CanLowerReturn) return false; if (Ret->getNumOperands() > 0) { return false; } emitInst(Mips::RetRA); return true; } bool MipsFastISel::selectTrunc(const Instruction *I) { // The high bits for a type smaller than the register size are assumed to be // undefined. Value *Op = I->getOperand(0); EVT SrcVT, DestVT; SrcVT = TLI.getValueType(Op->getType(), true); DestVT = TLI.getValueType(I->getType(), true); if (SrcVT != MVT::i32 && SrcVT != MVT::i16 && SrcVT != MVT::i8) return false; if (DestVT != MVT::i16 && DestVT != MVT::i8 && DestVT != MVT::i1) return false; unsigned SrcReg = getRegForValue(Op); if (!SrcReg) return false; // Because the high bits are undefined, a truncate doesn't generate // any code. updateValueMap(I, SrcReg); return true; } bool MipsFastISel::selectIntExt(const Instruction *I) { Type *DestTy = I->getType(); Value *Src = I->getOperand(0); Type *SrcTy = Src->getType(); bool isZExt = isa(I); unsigned SrcReg = getRegForValue(Src); if (!SrcReg) return false; EVT SrcEVT, DestEVT; SrcEVT = TLI.getValueType(SrcTy, true); DestEVT = TLI.getValueType(DestTy, true); if (!SrcEVT.isSimple()) return false; if (!DestEVT.isSimple()) return false; MVT SrcVT = SrcEVT.getSimpleVT(); MVT DestVT = DestEVT.getSimpleVT(); unsigned ResultReg = createResultReg(&Mips::GPR32RegClass); if (!emitIntExt(SrcVT, SrcReg, DestVT, ResultReg, isZExt)) return false; updateValueMap(I, ResultReg); return true; } bool MipsFastISel::emitIntSExt32r1(MVT SrcVT, unsigned SrcReg, MVT DestVT, unsigned DestReg) { unsigned ShiftAmt; switch (SrcVT.SimpleTy) { default: return false; case MVT::i8: ShiftAmt = 24; break; case MVT::i16: ShiftAmt = 16; break; } unsigned TempReg = createResultReg(&Mips::GPR32RegClass); emitInst(Mips::SLL, TempReg).addReg(SrcReg).addImm(ShiftAmt); emitInst(Mips::SRA, DestReg).addReg(TempReg).addImm(ShiftAmt); return true; } bool MipsFastISel::emitIntSExt32r2(MVT SrcVT, unsigned SrcReg, MVT DestVT, unsigned DestReg) { switch (SrcVT.SimpleTy) { default: return false; case MVT::i8: emitInst(Mips::SEB, DestReg).addReg(SrcReg); break; case MVT::i16: emitInst(Mips::SEH, DestReg).addReg(SrcReg); break; } return true; } bool MipsFastISel::emitIntSExt(MVT SrcVT, unsigned SrcReg, MVT DestVT, unsigned DestReg) { if ((DestVT != MVT::i32) && (DestVT != MVT::i16)) return false; if (Subtarget->hasMips32r2()) return emitIntSExt32r2(SrcVT, SrcReg, DestVT, DestReg); return emitIntSExt32r1(SrcVT, SrcReg, DestVT, DestReg); } bool MipsFastISel::emitIntZExt(MVT SrcVT, unsigned SrcReg, MVT DestVT, unsigned DestReg) { switch (SrcVT.SimpleTy) { default: return false; case MVT::i1: emitInst(Mips::ANDi, DestReg).addReg(SrcReg).addImm(1); break; case MVT::i8: emitInst(Mips::ANDi, DestReg).addReg(SrcReg).addImm(0xff); break; case MVT::i16: emitInst(Mips::ANDi, DestReg).addReg(SrcReg).addImm(0xffff); break; } return true; } bool MipsFastISel::emitIntExt(MVT SrcVT, unsigned SrcReg, MVT DestVT, unsigned DestReg, bool IsZExt) { if (IsZExt) return emitIntZExt(SrcVT, SrcReg, DestVT, DestReg); return emitIntSExt(SrcVT, SrcReg, DestVT, DestReg); } unsigned MipsFastISel::emitIntExt(MVT SrcVT, unsigned SrcReg, MVT DestVT, bool isZExt) { unsigned DestReg = createResultReg(&Mips::GPR32RegClass); return emitIntExt(SrcVT, SrcReg, DestVT, DestReg, isZExt); } bool MipsFastISel::fastSelectInstruction(const Instruction *I) { if (!TargetSupported) return false; switch (I->getOpcode()) { default: break; case Instruction::Load: return selectLoad(I); case Instruction::Store: return selectStore(I); case Instruction::Br: return selectBranch(I); case Instruction::Ret: return selectRet(I); case Instruction::Trunc: return selectTrunc(I); case Instruction::ZExt: case Instruction::SExt: return selectIntExt(I); case Instruction::FPTrunc: return selectFPTrunc(I); case Instruction::FPExt: return selectFPExt(I); case Instruction::FPToSI: return selectFPToInt(I, /*isSigned*/ true); case Instruction::FPToUI: return selectFPToInt(I, /*isSigned*/ false); case Instruction::ICmp: case Instruction::FCmp: return selectCmp(I); } return false; } unsigned MipsFastISel::getRegEnsuringSimpleIntegerWidening(const Value *V, bool IsUnsigned) { unsigned VReg = getRegForValue(V); if (VReg == 0) return 0; MVT VMVT = TLI.getValueType(V->getType(), true).getSimpleVT(); if ((VMVT == MVT::i8) || (VMVT == MVT::i16)) { unsigned TempReg = createResultReg(&Mips::GPR32RegClass); if (!emitIntExt(VMVT, VReg, MVT::i32, TempReg, IsUnsigned)) return 0; VReg = TempReg; } return VReg; } namespace llvm { FastISel *Mips::createFastISel(FunctionLoweringInfo &funcInfo, const TargetLibraryInfo *libInfo) { return new MipsFastISel(funcInfo, libInfo); } }