//===-- PPCISelDAGToDAG.cpp - PPC --pattern matching inst selector --------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This file defines a pattern matching instruction selector for PowerPC, // converting from a legalized dag to a PPC dag. // //===----------------------------------------------------------------------===// #define DEBUG_TYPE "ppc-codegen" #include "PPC.h" #include "PPCPredicates.h" #include "PPCTargetMachine.h" #include "PPCISelLowering.h" #include "PPCHazardRecognizers.h" #include "llvm/CodeGen/MachineInstrBuilder.h" #include "llvm/CodeGen/MachineFunction.h" #include "llvm/CodeGen/MachineFunctionAnalysis.h" #include "llvm/CodeGen/MachineRegisterInfo.h" #include "llvm/CodeGen/SelectionDAG.h" #include "llvm/CodeGen/SelectionDAGISel.h" #include "llvm/Target/TargetOptions.h" #include "llvm/Constants.h" #include "llvm/Function.h" #include "llvm/GlobalValue.h" #include "llvm/Intrinsics.h" #include "llvm/Support/Debug.h" #include "llvm/Support/MathExtras.h" #include "llvm/Support/Compiler.h" #include "llvm/Support/ErrorHandling.h" #include "llvm/Support/raw_ostream.h" using namespace llvm; namespace { //===--------------------------------------------------------------------===// /// PPCDAGToDAGISel - PPC specific code to select PPC machine /// instructions for SelectionDAG operations. /// class VISIBILITY_HIDDEN PPCDAGToDAGISel : public SelectionDAGISel { PPCTargetMachine &TM; PPCTargetLowering &PPCLowering; const PPCSubtarget &PPCSubTarget; unsigned GlobalBaseReg; public: explicit PPCDAGToDAGISel(PPCTargetMachine &tm) : SelectionDAGISel(tm), TM(tm), PPCLowering(*TM.getTargetLowering()), PPCSubTarget(*TM.getSubtargetImpl()) {} virtual bool runOnMachineFunction(MachineFunction &MF) { // Make sure we re-emit a set of the global base reg if necessary GlobalBaseReg = 0; SelectionDAGISel::runOnMachineFunction(MF); InsertVRSaveCode(MF); return true; } /// getI32Imm - Return a target constant with the specified value, of type /// i32. inline SDValue getI32Imm(unsigned Imm) { return CurDAG->getTargetConstant(Imm, MVT::i32); } /// getI64Imm - Return a target constant with the specified value, of type /// i64. inline SDValue getI64Imm(uint64_t Imm) { return CurDAG->getTargetConstant(Imm, MVT::i64); } /// getSmallIPtrImm - Return a target constant of pointer type. inline SDValue getSmallIPtrImm(unsigned Imm) { return CurDAG->getTargetConstant(Imm, PPCLowering.getPointerTy()); } /// isRunOfOnes - Returns true iff Val consists of one contiguous run of 1s /// with any number of 0s on either side. The 1s are allowed to wrap from /// LSB to MSB, so 0x000FFF0, 0x0000FFFF, and 0xFF0000FF are all runs. /// 0x0F0F0000 is not, since all 1s are not contiguous. static bool isRunOfOnes(unsigned Val, unsigned &MB, unsigned &ME); /// isRotateAndMask - Returns true if Mask and Shift can be folded into a /// rotate and mask opcode and mask operation. static bool isRotateAndMask(SDNode *N, unsigned Mask, bool IsShiftMask, unsigned &SH, unsigned &MB, unsigned &ME); /// getGlobalBaseReg - insert code into the entry mbb to materialize the PIC /// base register. Return the virtual register that holds this value. SDNode *getGlobalBaseReg(); // Select - Convert the specified operand from a target-independent to a // target-specific node if it hasn't already been changed. SDNode *Select(SDValue Op); SDNode *SelectBitfieldInsert(SDNode *N); /// SelectCC - Select a comparison of the specified values with the /// specified condition code, returning the CR# of the expression. SDValue SelectCC(SDValue LHS, SDValue RHS, ISD::CondCode CC, DebugLoc dl); /// SelectAddrImm - Returns true if the address N can be represented by /// a base register plus a signed 16-bit displacement [r+imm]. bool SelectAddrImm(SDValue Op, SDValue N, SDValue &Disp, SDValue &Base) { return PPCLowering.SelectAddressRegImm(N, Disp, Base, *CurDAG); } /// SelectAddrImmOffs - Return true if the operand is valid for a preinc /// immediate field. Because preinc imms have already been validated, just /// accept it. bool SelectAddrImmOffs(SDValue Op, SDValue N, SDValue &Out) const { Out = N; return true; } /// SelectAddrIdx - Given the specified addressed, check to see if it can be /// represented as an indexed [r+r] operation. Returns false if it can /// be represented by [r+imm], which are preferred. bool SelectAddrIdx(SDValue Op, SDValue N, SDValue &Base, SDValue &Index) { return PPCLowering.SelectAddressRegReg(N, Base, Index, *CurDAG); } /// SelectAddrIdxOnly - Given the specified addressed, force it to be /// represented as an indexed [r+r] operation. bool SelectAddrIdxOnly(SDValue Op, SDValue N, SDValue &Base, SDValue &Index) { return PPCLowering.SelectAddressRegRegOnly(N, Base, Index, *CurDAG); } /// SelectAddrImmShift - Returns true if the address N can be represented by /// a base register plus a signed 14-bit displacement [r+imm*4]. Suitable /// for use by STD and friends. bool SelectAddrImmShift(SDValue Op, SDValue N, SDValue &Disp, SDValue &Base) { return PPCLowering.SelectAddressRegImmShift(N, Disp, Base, *CurDAG); } /// SelectInlineAsmMemoryOperand - Implement addressing mode selection for /// inline asm expressions. It is always correct to compute the value into /// a register. The case of adding a (possibly relocatable) constant to a /// register can be improved, but it is wrong to substitute Reg+Reg for /// Reg in an asm, because the load or store opcode would have to change. virtual bool SelectInlineAsmMemoryOperand(const SDValue &Op, char ConstraintCode, std::vector &OutOps) { OutOps.push_back(Op); return false; } SDValue BuildSDIVSequence(SDNode *N); SDValue BuildUDIVSequence(SDNode *N); /// InstructionSelect - This callback is invoked by /// SelectionDAGISel when it has created a SelectionDAG for us to codegen. virtual void InstructionSelect(); void InsertVRSaveCode(MachineFunction &MF); virtual const char *getPassName() const { return "PowerPC DAG->DAG Pattern Instruction Selection"; } /// CreateTargetHazardRecognizer - Return the hazard recognizer to use for /// this target when scheduling the DAG. virtual ScheduleHazardRecognizer *CreateTargetHazardRecognizer() { // Should use subtarget info to pick the right hazard recognizer. For // now, always return a PPC970 recognizer. const TargetInstrInfo *II = TM.getInstrInfo(); assert(II && "No InstrInfo?"); return new PPCHazardRecognizer970(*II); } // Include the pieces autogenerated from the target description. #include "PPCGenDAGISel.inc" private: SDNode *SelectSETCC(SDValue Op); }; } /// InstructionSelect - This callback is invoked by /// SelectionDAGISel when it has created a SelectionDAG for us to codegen. void PPCDAGToDAGISel::InstructionSelect() { DEBUG(BB->dump()); // Select target instructions for the DAG. SelectRoot(*CurDAG); CurDAG->RemoveDeadNodes(); } /// InsertVRSaveCode - Once the entire function has been instruction selected, /// all virtual registers are created and all machine instructions are built, /// check to see if we need to save/restore VRSAVE. If so, do it. void PPCDAGToDAGISel::InsertVRSaveCode(MachineFunction &Fn) { // Check to see if this function uses vector registers, which means we have to // save and restore the VRSAVE register and update it with the regs we use. // // In this case, there will be virtual registers of vector type type created // by the scheduler. Detect them now. bool HasVectorVReg = false; for (unsigned i = TargetRegisterInfo::FirstVirtualRegister, e = RegInfo->getLastVirtReg()+1; i != e; ++i) if (RegInfo->getRegClass(i) == &PPC::VRRCRegClass) { HasVectorVReg = true; break; } if (!HasVectorVReg) return; // nothing to do. // If we have a vector register, we want to emit code into the entry and exit // blocks to save and restore the VRSAVE register. We do this here (instead // of marking all vector instructions as clobbering VRSAVE) for two reasons: // // 1. This (trivially) reduces the load on the register allocator, by not // having to represent the live range of the VRSAVE register. // 2. This (more significantly) allows us to create a temporary virtual // register to hold the saved VRSAVE value, allowing this temporary to be // register allocated, instead of forcing it to be spilled to the stack. // Create two vregs - one to hold the VRSAVE register that is live-in to the // function and one for the value after having bits or'd into it. unsigned InVRSAVE = RegInfo->createVirtualRegister(&PPC::GPRCRegClass); unsigned UpdatedVRSAVE = RegInfo->createVirtualRegister(&PPC::GPRCRegClass); const TargetInstrInfo &TII = *TM.getInstrInfo(); MachineBasicBlock &EntryBB = *Fn.begin(); DebugLoc dl = DebugLoc::getUnknownLoc(); // Emit the following code into the entry block: // InVRSAVE = MFVRSAVE // UpdatedVRSAVE = UPDATE_VRSAVE InVRSAVE // MTVRSAVE UpdatedVRSAVE MachineBasicBlock::iterator IP = EntryBB.begin(); // Insert Point BuildMI(EntryBB, IP, dl, TII.get(PPC::MFVRSAVE), InVRSAVE); BuildMI(EntryBB, IP, dl, TII.get(PPC::UPDATE_VRSAVE), UpdatedVRSAVE).addReg(InVRSAVE); BuildMI(EntryBB, IP, dl, TII.get(PPC::MTVRSAVE)).addReg(UpdatedVRSAVE); // Find all return blocks, outputting a restore in each epilog. for (MachineFunction::iterator BB = Fn.begin(), E = Fn.end(); BB != E; ++BB) { if (!BB->empty() && BB->back().getDesc().isReturn()) { IP = BB->end(); --IP; // Skip over all terminator instructions, which are part of the return // sequence. MachineBasicBlock::iterator I2 = IP; while (I2 != BB->begin() && (--I2)->getDesc().isTerminator()) IP = I2; // Emit: MTVRSAVE InVRSave BuildMI(*BB, IP, dl, TII.get(PPC::MTVRSAVE)).addReg(InVRSAVE); } } } /// getGlobalBaseReg - Output the instructions required to put the /// base address to use for accessing globals into a register. /// SDNode *PPCDAGToDAGISel::getGlobalBaseReg() { if (!GlobalBaseReg) { const TargetInstrInfo &TII = *TM.getInstrInfo(); // Insert the set of GlobalBaseReg into the first MBB of the function MachineBasicBlock &FirstMBB = MF->front(); MachineBasicBlock::iterator MBBI = FirstMBB.begin(); DebugLoc dl = DebugLoc::getUnknownLoc(); if (PPCLowering.getPointerTy() == MVT::i32) { GlobalBaseReg = RegInfo->createVirtualRegister(PPC::GPRCRegisterClass); BuildMI(FirstMBB, MBBI, dl, TII.get(PPC::MovePCtoLR), PPC::LR); BuildMI(FirstMBB, MBBI, dl, TII.get(PPC::MFLR), GlobalBaseReg); } else { GlobalBaseReg = RegInfo->createVirtualRegister(PPC::G8RCRegisterClass); BuildMI(FirstMBB, MBBI, dl, TII.get(PPC::MovePCtoLR8), PPC::LR8); BuildMI(FirstMBB, MBBI, dl, TII.get(PPC::MFLR8), GlobalBaseReg); } } return CurDAG->getRegister(GlobalBaseReg, PPCLowering.getPointerTy()).getNode(); } /// isIntS16Immediate - This method tests to see if the node is either a 32-bit /// or 64-bit immediate, and if the value can be accurately represented as a /// sign extension from a 16-bit value. If so, this returns true and the /// immediate. static bool isIntS16Immediate(SDNode *N, short &Imm) { if (N->getOpcode() != ISD::Constant) return false; Imm = (short)cast(N)->getZExtValue(); if (N->getValueType(0) == MVT::i32) return Imm == (int32_t)cast(N)->getZExtValue(); else return Imm == (int64_t)cast(N)->getZExtValue(); } static bool isIntS16Immediate(SDValue Op, short &Imm) { return isIntS16Immediate(Op.getNode(), Imm); } /// isInt32Immediate - This method tests to see if the node is a 32-bit constant /// operand. If so Imm will receive the 32-bit value. static bool isInt32Immediate(SDNode *N, unsigned &Imm) { if (N->getOpcode() == ISD::Constant && N->getValueType(0) == MVT::i32) { Imm = cast(N)->getZExtValue(); return true; } return false; } /// isInt64Immediate - This method tests to see if the node is a 64-bit constant /// operand. If so Imm will receive the 64-bit value. static bool isInt64Immediate(SDNode *N, uint64_t &Imm) { if (N->getOpcode() == ISD::Constant && N->getValueType(0) == MVT::i64) { Imm = cast(N)->getZExtValue(); return true; } return false; } // isInt32Immediate - This method tests to see if a constant operand. // If so Imm will receive the 32 bit value. static bool isInt32Immediate(SDValue N, unsigned &Imm) { return isInt32Immediate(N.getNode(), Imm); } // isOpcWithIntImmediate - This method tests to see if the node is a specific // opcode and that it has a immediate integer right operand. // If so Imm will receive the 32 bit value. static bool isOpcWithIntImmediate(SDNode *N, unsigned Opc, unsigned& Imm) { return N->getOpcode() == Opc && isInt32Immediate(N->getOperand(1).getNode(), Imm); } bool PPCDAGToDAGISel::isRunOfOnes(unsigned Val, unsigned &MB, unsigned &ME) { if (isShiftedMask_32(Val)) { // look for the first non-zero bit MB = CountLeadingZeros_32(Val); // look for the first zero bit after the run of ones ME = CountLeadingZeros_32((Val - 1) ^ Val); return true; } else { Val = ~Val; // invert mask if (isShiftedMask_32(Val)) { // effectively look for the first zero bit ME = CountLeadingZeros_32(Val) - 1; // effectively look for the first one bit after the run of zeros MB = CountLeadingZeros_32((Val - 1) ^ Val) + 1; return true; } } // no run present return false; } bool PPCDAGToDAGISel::isRotateAndMask(SDNode *N, unsigned Mask, bool IsShiftMask, unsigned &SH, unsigned &MB, unsigned &ME) { // Don't even go down this path for i64, since different logic will be // necessary for rldicl/rldicr/rldimi. if (N->getValueType(0) != MVT::i32) return false; unsigned Shift = 32; unsigned Indeterminant = ~0; // bit mask marking indeterminant results unsigned Opcode = N->getOpcode(); if (N->getNumOperands() != 2 || !isInt32Immediate(N->getOperand(1).getNode(), Shift) || (Shift > 31)) return false; if (Opcode == ISD::SHL) { // apply shift left to mask if it comes first if (IsShiftMask) Mask = Mask << Shift; // determine which bits are made indeterminant by shift Indeterminant = ~(0xFFFFFFFFu << Shift); } else if (Opcode == ISD::SRL) { // apply shift right to mask if it comes first if (IsShiftMask) Mask = Mask >> Shift; // determine which bits are made indeterminant by shift Indeterminant = ~(0xFFFFFFFFu >> Shift); // adjust for the left rotate Shift = 32 - Shift; } else if (Opcode == ISD::ROTL) { Indeterminant = 0; } else { return false; } // if the mask doesn't intersect any Indeterminant bits if (Mask && !(Mask & Indeterminant)) { SH = Shift & 31; // make sure the mask is still a mask (wrap arounds may not be) return isRunOfOnes(Mask, MB, ME); } return false; } /// SelectBitfieldInsert - turn an or of two masked values into /// the rotate left word immediate then mask insert (rlwimi) instruction. SDNode *PPCDAGToDAGISel::SelectBitfieldInsert(SDNode *N) { SDValue Op0 = N->getOperand(0); SDValue Op1 = N->getOperand(1); DebugLoc dl = N->getDebugLoc(); APInt LKZ, LKO, RKZ, RKO; CurDAG->ComputeMaskedBits(Op0, APInt::getAllOnesValue(32), LKZ, LKO); CurDAG->ComputeMaskedBits(Op1, APInt::getAllOnesValue(32), RKZ, RKO); unsigned TargetMask = LKZ.getZExtValue(); unsigned InsertMask = RKZ.getZExtValue(); if ((TargetMask | InsertMask) == 0xFFFFFFFF) { unsigned Op0Opc = Op0.getOpcode(); unsigned Op1Opc = Op1.getOpcode(); unsigned Value, SH = 0; TargetMask = ~TargetMask; InsertMask = ~InsertMask; // If the LHS has a foldable shift and the RHS does not, then swap it to the // RHS so that we can fold the shift into the insert. if (Op0Opc == ISD::AND && Op1Opc == ISD::AND) { if (Op0.getOperand(0).getOpcode() == ISD::SHL || Op0.getOperand(0).getOpcode() == ISD::SRL) { if (Op1.getOperand(0).getOpcode() != ISD::SHL && Op1.getOperand(0).getOpcode() != ISD::SRL) { std::swap(Op0, Op1); std::swap(Op0Opc, Op1Opc); std::swap(TargetMask, InsertMask); } } } else if (Op0Opc == ISD::SHL || Op0Opc == ISD::SRL) { if (Op1Opc == ISD::AND && Op1.getOperand(0).getOpcode() != ISD::SHL && Op1.getOperand(0).getOpcode() != ISD::SRL) { std::swap(Op0, Op1); std::swap(Op0Opc, Op1Opc); std::swap(TargetMask, InsertMask); } } unsigned MB, ME; if (InsertMask && isRunOfOnes(InsertMask, MB, ME)) { SDValue Tmp1, Tmp2, Tmp3; bool DisjointMask = (TargetMask ^ InsertMask) == 0xFFFFFFFF; if ((Op1Opc == ISD::SHL || Op1Opc == ISD::SRL) && isInt32Immediate(Op1.getOperand(1), Value)) { Op1 = Op1.getOperand(0); SH = (Op1Opc == ISD::SHL) ? Value : 32 - Value; } if (Op1Opc == ISD::AND) { unsigned SHOpc = Op1.getOperand(0).getOpcode(); if ((SHOpc == ISD::SHL || SHOpc == ISD::SRL) && isInt32Immediate(Op1.getOperand(0).getOperand(1), Value)) { Op1 = Op1.getOperand(0).getOperand(0); SH = (SHOpc == ISD::SHL) ? Value : 32 - Value; } else { Op1 = Op1.getOperand(0); } } Tmp3 = (Op0Opc == ISD::AND && DisjointMask) ? Op0.getOperand(0) : Op0; SH &= 31; SDValue Ops[] = { Tmp3, Op1, getI32Imm(SH), getI32Imm(MB), getI32Imm(ME) }; return CurDAG->getTargetNode(PPC::RLWIMI, dl, MVT::i32, Ops, 5); } } return 0; } /// SelectCC - Select a comparison of the specified values with the specified /// condition code, returning the CR# of the expression. SDValue PPCDAGToDAGISel::SelectCC(SDValue LHS, SDValue RHS, ISD::CondCode CC, DebugLoc dl) { // Always select the LHS. unsigned Opc; if (LHS.getValueType() == MVT::i32) { unsigned Imm; if (CC == ISD::SETEQ || CC == ISD::SETNE) { if (isInt32Immediate(RHS, Imm)) { // SETEQ/SETNE comparison with 16-bit immediate, fold it. if (isUInt16(Imm)) return SDValue(CurDAG->getTargetNode(PPC::CMPLWI, dl, MVT::i32, LHS, getI32Imm(Imm & 0xFFFF)), 0); // If this is a 16-bit signed immediate, fold it. if (isInt16((int)Imm)) return SDValue(CurDAG->getTargetNode(PPC::CMPWI, dl, MVT::i32, LHS, getI32Imm(Imm & 0xFFFF)), 0); // For non-equality comparisons, the default code would materialize the // constant, then compare against it, like this: // lis r2, 4660 // ori r2, r2, 22136 // cmpw cr0, r3, r2 // Since we are just comparing for equality, we can emit this instead: // xoris r0,r3,0x1234 // cmplwi cr0,r0,0x5678 // beq cr0,L6 SDValue Xor(CurDAG->getTargetNode(PPC::XORIS, dl, MVT::i32, LHS, getI32Imm(Imm >> 16)), 0); return SDValue(CurDAG->getTargetNode(PPC::CMPLWI, dl, MVT::i32, Xor, getI32Imm(Imm & 0xFFFF)), 0); } Opc = PPC::CMPLW; } else if (ISD::isUnsignedIntSetCC(CC)) { if (isInt32Immediate(RHS, Imm) && isUInt16(Imm)) return SDValue(CurDAG->getTargetNode(PPC::CMPLWI, dl, MVT::i32, LHS, getI32Imm(Imm & 0xFFFF)), 0); Opc = PPC::CMPLW; } else { short SImm; if (isIntS16Immediate(RHS, SImm)) return SDValue(CurDAG->getTargetNode(PPC::CMPWI, dl, MVT::i32, LHS, getI32Imm((int)SImm & 0xFFFF)), 0); Opc = PPC::CMPW; } } else if (LHS.getValueType() == MVT::i64) { uint64_t Imm; if (CC == ISD::SETEQ || CC == ISD::SETNE) { if (isInt64Immediate(RHS.getNode(), Imm)) { // SETEQ/SETNE comparison with 16-bit immediate, fold it. if (isUInt16(Imm)) return SDValue(CurDAG->getTargetNode(PPC::CMPLDI, dl, MVT::i64, LHS, getI32Imm(Imm & 0xFFFF)), 0); // If this is a 16-bit signed immediate, fold it. if (isInt16(Imm)) return SDValue(CurDAG->getTargetNode(PPC::CMPDI, dl, MVT::i64, LHS, getI32Imm(Imm & 0xFFFF)), 0); // For non-equality comparisons, the default code would materialize the // constant, then compare against it, like this: // lis r2, 4660 // ori r2, r2, 22136 // cmpd cr0, r3, r2 // Since we are just comparing for equality, we can emit this instead: // xoris r0,r3,0x1234 // cmpldi cr0,r0,0x5678 // beq cr0,L6 if (isUInt32(Imm)) { SDValue Xor(CurDAG->getTargetNode(PPC::XORIS8, dl, MVT::i64, LHS, getI64Imm(Imm >> 16)), 0); return SDValue(CurDAG->getTargetNode(PPC::CMPLDI, dl, MVT::i64, Xor, getI64Imm(Imm & 0xFFFF)), 0); } } Opc = PPC::CMPLD; } else if (ISD::isUnsignedIntSetCC(CC)) { if (isInt64Immediate(RHS.getNode(), Imm) && isUInt16(Imm)) return SDValue(CurDAG->getTargetNode(PPC::CMPLDI, dl, MVT::i64, LHS, getI64Imm(Imm & 0xFFFF)), 0); Opc = PPC::CMPLD; } else { short SImm; if (isIntS16Immediate(RHS, SImm)) return SDValue(CurDAG->getTargetNode(PPC::CMPDI, dl, MVT::i64, LHS, getI64Imm(SImm & 0xFFFF)), 0); Opc = PPC::CMPD; } } else if (LHS.getValueType() == MVT::f32) { Opc = PPC::FCMPUS; } else { assert(LHS.getValueType() == MVT::f64 && "Unknown vt!"); Opc = PPC::FCMPUD; } return SDValue(CurDAG->getTargetNode(Opc, dl, MVT::i32, LHS, RHS), 0); } static PPC::Predicate getPredicateForSetCC(ISD::CondCode CC) { switch (CC) { case ISD::SETUEQ: case ISD::SETONE: case ISD::SETOLE: case ISD::SETOGE: llvm_unreachable("Should be lowered by legalize!"); default: llvm_unreachable("Unknown condition!"); case ISD::SETOEQ: case ISD::SETEQ: return PPC::PRED_EQ; case ISD::SETUNE: case ISD::SETNE: return PPC::PRED_NE; case ISD::SETOLT: case ISD::SETLT: return PPC::PRED_LT; case ISD::SETULE: case ISD::SETLE: return PPC::PRED_LE; case ISD::SETOGT: case ISD::SETGT: return PPC::PRED_GT; case ISD::SETUGE: case ISD::SETGE: return PPC::PRED_GE; case ISD::SETO: return PPC::PRED_NU; case ISD::SETUO: return PPC::PRED_UN; // These two are invalid for floating point. Assume we have int. case ISD::SETULT: return PPC::PRED_LT; case ISD::SETUGT: return PPC::PRED_GT; } } /// getCRIdxForSetCC - Return the index of the condition register field /// associated with the SetCC condition, and whether or not the field is /// treated as inverted. That is, lt = 0; ge = 0 inverted. /// /// If this returns with Other != -1, then the returned comparison is an or of /// two simpler comparisons. In this case, Invert is guaranteed to be false. static unsigned getCRIdxForSetCC(ISD::CondCode CC, bool &Invert, int &Other) { Invert = false; Other = -1; switch (CC) { default: llvm_unreachable("Unknown condition!"); case ISD::SETOLT: case ISD::SETLT: return 0; // Bit #0 = SETOLT case ISD::SETOGT: case ISD::SETGT: return 1; // Bit #1 = SETOGT case ISD::SETOEQ: case ISD::SETEQ: return 2; // Bit #2 = SETOEQ case ISD::SETUO: return 3; // Bit #3 = SETUO case ISD::SETUGE: case ISD::SETGE: Invert = true; return 0; // !Bit #0 = SETUGE case ISD::SETULE: case ISD::SETLE: Invert = true; return 1; // !Bit #1 = SETULE case ISD::SETUNE: case ISD::SETNE: Invert = true; return 2; // !Bit #2 = SETUNE case ISD::SETO: Invert = true; return 3; // !Bit #3 = SETO case ISD::SETUEQ: case ISD::SETOGE: case ISD::SETOLE: case ISD::SETONE: llvm_unreachable("Invalid branch code: should be expanded by legalize"); // These are invalid for floating point. Assume integer. case ISD::SETULT: return 0; case ISD::SETUGT: return 1; } return 0; } SDNode *PPCDAGToDAGISel::SelectSETCC(SDValue Op) { SDNode *N = Op.getNode(); DebugLoc dl = N->getDebugLoc(); unsigned Imm; ISD::CondCode CC = cast(N->getOperand(2))->get(); if (isInt32Immediate(N->getOperand(1), Imm)) { // We can codegen setcc op, imm very efficiently compared to a brcond. // Check for those cases here. // setcc op, 0 if (Imm == 0) { SDValue Op = N->getOperand(0); switch (CC) { default: break; case ISD::SETEQ: { Op = SDValue(CurDAG->getTargetNode(PPC::CNTLZW, dl, MVT::i32, Op), 0); SDValue Ops[] = { Op, getI32Imm(27), getI32Imm(5), getI32Imm(31) }; return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops, 4); } case ISD::SETNE: { SDValue AD = SDValue(CurDAG->getTargetNode(PPC::ADDIC, dl, MVT::i32, MVT::Flag, Op, getI32Imm(~0U)), 0); return CurDAG->SelectNodeTo(N, PPC::SUBFE, MVT::i32, AD, Op, AD.getValue(1)); } case ISD::SETLT: { SDValue Ops[] = { Op, getI32Imm(1), getI32Imm(31), getI32Imm(31) }; return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops, 4); } case ISD::SETGT: { SDValue T = SDValue(CurDAG->getTargetNode(PPC::NEG, dl, MVT::i32, Op), 0); T = SDValue(CurDAG->getTargetNode(PPC::ANDC, dl, MVT::i32, T, Op), 0); SDValue Ops[] = { T, getI32Imm(1), getI32Imm(31), getI32Imm(31) }; return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops, 4); } } } else if (Imm == ~0U) { // setcc op, -1 SDValue Op = N->getOperand(0); switch (CC) { default: break; case ISD::SETEQ: Op = SDValue(CurDAG->getTargetNode(PPC::ADDIC, dl, MVT::i32, MVT::Flag, Op, getI32Imm(1)), 0); return CurDAG->SelectNodeTo(N, PPC::ADDZE, MVT::i32, SDValue(CurDAG->getTargetNode(PPC::LI, dl, MVT::i32, getI32Imm(0)), 0), Op.getValue(1)); case ISD::SETNE: { Op = SDValue(CurDAG->getTargetNode(PPC::NOR, dl, MVT::i32, Op, Op), 0); SDNode *AD = CurDAG->getTargetNode(PPC::ADDIC, dl, MVT::i32, MVT::Flag, Op, getI32Imm(~0U)); return CurDAG->SelectNodeTo(N, PPC::SUBFE, MVT::i32, SDValue(AD, 0), Op, SDValue(AD, 1)); } case ISD::SETLT: { SDValue AD = SDValue(CurDAG->getTargetNode(PPC::ADDI, dl, MVT::i32, Op, getI32Imm(1)), 0); SDValue AN = SDValue(CurDAG->getTargetNode(PPC::AND, dl, MVT::i32, AD, Op), 0); SDValue Ops[] = { AN, getI32Imm(1), getI32Imm(31), getI32Imm(31) }; return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops, 4); } case ISD::SETGT: { SDValue Ops[] = { Op, getI32Imm(1), getI32Imm(31), getI32Imm(31) }; Op = SDValue(CurDAG->getTargetNode(PPC::RLWINM, dl, MVT::i32, Ops, 4), 0); return CurDAG->SelectNodeTo(N, PPC::XORI, MVT::i32, Op, getI32Imm(1)); } } } } bool Inv; int OtherCondIdx; unsigned Idx = getCRIdxForSetCC(CC, Inv, OtherCondIdx); SDValue CCReg = SelectCC(N->getOperand(0), N->getOperand(1), CC, dl); SDValue IntCR; // Force the ccreg into CR7. SDValue CR7Reg = CurDAG->getRegister(PPC::CR7, MVT::i32); SDValue InFlag(0, 0); // Null incoming flag value. CCReg = CurDAG->getCopyToReg(CurDAG->getEntryNode(), dl, CR7Reg, CCReg, InFlag).getValue(1); if (PPCSubTarget.isGigaProcessor() && OtherCondIdx == -1) IntCR = SDValue(CurDAG->getTargetNode(PPC::MFOCRF, dl, MVT::i32, CR7Reg, CCReg), 0); else IntCR = SDValue(CurDAG->getTargetNode(PPC::MFCR, dl, MVT::i32, CCReg), 0); SDValue Ops[] = { IntCR, getI32Imm((32-(3-Idx)) & 31), getI32Imm(31), getI32Imm(31) }; if (OtherCondIdx == -1 && !Inv) return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops, 4); // Get the specified bit. SDValue Tmp = SDValue(CurDAG->getTargetNode(PPC::RLWINM, dl, MVT::i32, Ops, 4), 0); if (Inv) { assert(OtherCondIdx == -1 && "Can't have split plus negation"); return CurDAG->SelectNodeTo(N, PPC::XORI, MVT::i32, Tmp, getI32Imm(1)); } // Otherwise, we have to turn an operation like SETONE -> SETOLT | SETOGT. // We already got the bit for the first part of the comparison (e.g. SETULE). // Get the other bit of the comparison. Ops[1] = getI32Imm((32-(3-OtherCondIdx)) & 31); SDValue OtherCond = SDValue(CurDAG->getTargetNode(PPC::RLWINM, dl, MVT::i32, Ops, 4), 0); return CurDAG->SelectNodeTo(N, PPC::OR, MVT::i32, Tmp, OtherCond); } // Select - Convert the specified operand from a target-independent to a // target-specific node if it hasn't already been changed. SDNode *PPCDAGToDAGISel::Select(SDValue Op) { SDNode *N = Op.getNode(); DebugLoc dl = Op.getDebugLoc(); if (N->isMachineOpcode()) return NULL; // Already selected. switch (N->getOpcode()) { default: break; case ISD::Constant: { if (N->getValueType(0) == MVT::i64) { // Get 64 bit value. int64_t Imm = cast(N)->getZExtValue(); // Assume no remaining bits. unsigned Remainder = 0; // Assume no shift required. unsigned Shift = 0; // If it can't be represented as a 32 bit value. if (!isInt32(Imm)) { Shift = CountTrailingZeros_64(Imm); int64_t ImmSh = static_cast(Imm) >> Shift; // If the shifted value fits 32 bits. if (isInt32(ImmSh)) { // Go with the shifted value. Imm = ImmSh; } else { // Still stuck with a 64 bit value. Remainder = Imm; Shift = 32; Imm >>= 32; } } // Intermediate operand. SDNode *Result; // Handle first 32 bits. unsigned Lo = Imm & 0xFFFF; unsigned Hi = (Imm >> 16) & 0xFFFF; // Simple value. if (isInt16(Imm)) { // Just the Lo bits. Result = CurDAG->getTargetNode(PPC::LI8, dl, MVT::i64, getI32Imm(Lo)); } else if (Lo) { // Handle the Hi bits. unsigned OpC = Hi ? PPC::LIS8 : PPC::LI8; Result = CurDAG->getTargetNode(OpC, dl, MVT::i64, getI32Imm(Hi)); // And Lo bits. Result = CurDAG->getTargetNode(PPC::ORI8, dl, MVT::i64, SDValue(Result, 0), getI32Imm(Lo)); } else { // Just the Hi bits. Result = CurDAG->getTargetNode(PPC::LIS8, dl, MVT::i64, getI32Imm(Hi)); } // If no shift, we're done. if (!Shift) return Result; // Shift for next step if the upper 32-bits were not zero. if (Imm) { Result = CurDAG->getTargetNode(PPC::RLDICR, dl, MVT::i64, SDValue(Result, 0), getI32Imm(Shift), getI32Imm(63 - Shift)); } // Add in the last bits as required. if ((Hi = (Remainder >> 16) & 0xFFFF)) { Result = CurDAG->getTargetNode(PPC::ORIS8, dl, MVT::i64, SDValue(Result, 0), getI32Imm(Hi)); } if ((Lo = Remainder & 0xFFFF)) { Result = CurDAG->getTargetNode(PPC::ORI8, dl, MVT::i64, SDValue(Result, 0), getI32Imm(Lo)); } return Result; } break; } case ISD::SETCC: return SelectSETCC(Op); case PPCISD::GlobalBaseReg: return getGlobalBaseReg(); case ISD::FrameIndex: { int FI = cast(N)->getIndex(); SDValue TFI = CurDAG->getTargetFrameIndex(FI, Op.getValueType()); unsigned Opc = Op.getValueType() == MVT::i32 ? PPC::ADDI : PPC::ADDI8; if (N->hasOneUse()) return CurDAG->SelectNodeTo(N, Opc, Op.getValueType(), TFI, getSmallIPtrImm(0)); return CurDAG->getTargetNode(Opc, dl, Op.getValueType(), TFI, getSmallIPtrImm(0)); } case PPCISD::MFCR: { SDValue InFlag = N->getOperand(1); // Use MFOCRF if supported. if (PPCSubTarget.isGigaProcessor()) return CurDAG->getTargetNode(PPC::MFOCRF, dl, MVT::i32, N->getOperand(0), InFlag); else return CurDAG->getTargetNode(PPC::MFCR, dl, MVT::i32, InFlag); } case ISD::SDIV: { // FIXME: since this depends on the setting of the carry flag from the srawi // we should really be making notes about that for the scheduler. // FIXME: It sure would be nice if we could cheaply recognize the // srl/add/sra pattern the dag combiner will generate for this as // sra/addze rather than having to handle sdiv ourselves. oh well. unsigned Imm; if (isInt32Immediate(N->getOperand(1), Imm)) { SDValue N0 = N->getOperand(0); if ((signed)Imm > 0 && isPowerOf2_32(Imm)) { SDNode *Op = CurDAG->getTargetNode(PPC::SRAWI, dl, MVT::i32, MVT::Flag, N0, getI32Imm(Log2_32(Imm))); return CurDAG->SelectNodeTo(N, PPC::ADDZE, MVT::i32, SDValue(Op, 0), SDValue(Op, 1)); } else if ((signed)Imm < 0 && isPowerOf2_32(-Imm)) { SDNode *Op = CurDAG->getTargetNode(PPC::SRAWI, dl, MVT::i32, MVT::Flag, N0, getI32Imm(Log2_32(-Imm))); SDValue PT = SDValue(CurDAG->getTargetNode(PPC::ADDZE, dl, MVT::i32, SDValue(Op, 0), SDValue(Op, 1)), 0); return CurDAG->SelectNodeTo(N, PPC::NEG, MVT::i32, PT); } } // Other cases are autogenerated. break; } case ISD::LOAD: { // Handle preincrement loads. LoadSDNode *LD = cast(Op); EVT LoadedVT = LD->getMemoryVT(); // Normal loads are handled by code generated from the .td file. if (LD->getAddressingMode() != ISD::PRE_INC) break; SDValue Offset = LD->getOffset(); if (isa(Offset) || Offset.getOpcode() == ISD::TargetGlobalAddress) { unsigned Opcode; bool isSExt = LD->getExtensionType() == ISD::SEXTLOAD; if (LD->getValueType(0) != MVT::i64) { // Handle PPC32 integer and normal FP loads. assert((!isSExt || LoadedVT == MVT::i16) && "Invalid sext update load"); switch (LoadedVT.getSimpleVT().SimpleTy) { default: llvm_unreachable("Invalid PPC load type!"); case MVT::f64: Opcode = PPC::LFDU; break; case MVT::f32: Opcode = PPC::LFSU; break; case MVT::i32: Opcode = PPC::LWZU; break; case MVT::i16: Opcode = isSExt ? PPC::LHAU : PPC::LHZU; break; case MVT::i1: case MVT::i8: Opcode = PPC::LBZU; break; } } else { assert(LD->getValueType(0) == MVT::i64 && "Unknown load result type!"); assert((!isSExt || LoadedVT == MVT::i16) && "Invalid sext update load"); switch (LoadedVT.getSimpleVT().SimpleTy) { default: llvm_unreachable("Invalid PPC load type!"); case MVT::i64: Opcode = PPC::LDU; break; case MVT::i32: Opcode = PPC::LWZU8; break; case MVT::i16: Opcode = isSExt ? PPC::LHAU8 : PPC::LHZU8; break; case MVT::i1: case MVT::i8: Opcode = PPC::LBZU8; break; } } SDValue Chain = LD->getChain(); SDValue Base = LD->getBasePtr(); SDValue Ops[] = { Offset, Base, Chain }; // FIXME: PPC64 return CurDAG->getTargetNode(Opcode, dl, LD->getValueType(0), PPCLowering.getPointerTy(), MVT::Other, Ops, 3); } else { llvm_unreachable("R+R preindex loads not supported yet!"); } } case ISD::AND: { unsigned Imm, Imm2, SH, MB, ME; // If this is an and of a value rotated between 0 and 31 bits and then and'd // with a mask, emit rlwinm if (isInt32Immediate(N->getOperand(1), Imm) && isRotateAndMask(N->getOperand(0).getNode(), Imm, false, SH, MB, ME)) { SDValue Val = N->getOperand(0).getOperand(0); SDValue Ops[] = { Val, getI32Imm(SH), getI32Imm(MB), getI32Imm(ME) }; return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops, 4); } // If this is just a masked value where the input is not handled above, and // is not a rotate-left (handled by a pattern in the .td file), emit rlwinm if (isInt32Immediate(N->getOperand(1), Imm) && isRunOfOnes(Imm, MB, ME) && N->getOperand(0).getOpcode() != ISD::ROTL) { SDValue Val = N->getOperand(0); SDValue Ops[] = { Val, getI32Imm(0), getI32Imm(MB), getI32Imm(ME) }; return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops, 4); } // AND X, 0 -> 0, not "rlwinm 32". if (isInt32Immediate(N->getOperand(1), Imm) && (Imm == 0)) { ReplaceUses(SDValue(N, 0), N->getOperand(1)); return NULL; } // ISD::OR doesn't get all the bitfield insertion fun. // (and (or x, c1), c2) where isRunOfOnes(~(c1^c2)) is a bitfield insert if (isInt32Immediate(N->getOperand(1), Imm) && N->getOperand(0).getOpcode() == ISD::OR && isInt32Immediate(N->getOperand(0).getOperand(1), Imm2)) { unsigned MB, ME; Imm = ~(Imm^Imm2); if (isRunOfOnes(Imm, MB, ME)) { SDValue Ops[] = { N->getOperand(0).getOperand(0), N->getOperand(0).getOperand(1), getI32Imm(0), getI32Imm(MB),getI32Imm(ME) }; return CurDAG->getTargetNode(PPC::RLWIMI, dl, MVT::i32, Ops, 5); } } // Other cases are autogenerated. break; } case ISD::OR: if (N->getValueType(0) == MVT::i32) if (SDNode *I = SelectBitfieldInsert(N)) return I; // Other cases are autogenerated. break; case ISD::SHL: { unsigned Imm, SH, MB, ME; if (isOpcWithIntImmediate(N->getOperand(0).getNode(), ISD::AND, Imm) && isRotateAndMask(N, Imm, true, SH, MB, ME)) { SDValue Ops[] = { N->getOperand(0).getOperand(0), getI32Imm(SH), getI32Imm(MB), getI32Imm(ME) }; return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops, 4); } // Other cases are autogenerated. break; } case ISD::SRL: { unsigned Imm, SH, MB, ME; if (isOpcWithIntImmediate(N->getOperand(0).getNode(), ISD::AND, Imm) && isRotateAndMask(N, Imm, true, SH, MB, ME)) { SDValue Ops[] = { N->getOperand(0).getOperand(0), getI32Imm(SH), getI32Imm(MB), getI32Imm(ME) }; return CurDAG->SelectNodeTo(N, PPC::RLWINM, MVT::i32, Ops, 4); } // Other cases are autogenerated. break; } case ISD::SELECT_CC: { ISD::CondCode CC = cast(N->getOperand(4))->get(); // Handle the setcc cases here. select_cc lhs, 0, 1, 0, cc if (ConstantSDNode *N1C = dyn_cast(N->getOperand(1))) if (ConstantSDNode *N2C = dyn_cast(N->getOperand(2))) if (ConstantSDNode *N3C = dyn_cast(N->getOperand(3))) if (N1C->isNullValue() && N3C->isNullValue() && N2C->getZExtValue() == 1ULL && CC == ISD::SETNE && // FIXME: Implement this optzn for PPC64. N->getValueType(0) == MVT::i32) { SDNode *Tmp = CurDAG->getTargetNode(PPC::ADDIC, dl, MVT::i32, MVT::Flag, N->getOperand(0), getI32Imm(~0U)); return CurDAG->SelectNodeTo(N, PPC::SUBFE, MVT::i32, SDValue(Tmp, 0), N->getOperand(0), SDValue(Tmp, 1)); } SDValue CCReg = SelectCC(N->getOperand(0), N->getOperand(1), CC, dl); unsigned BROpc = getPredicateForSetCC(CC); unsigned SelectCCOp; if (N->getValueType(0) == MVT::i32) SelectCCOp = PPC::SELECT_CC_I4; else if (N->getValueType(0) == MVT::i64) SelectCCOp = PPC::SELECT_CC_I8; else if (N->getValueType(0) == MVT::f32) SelectCCOp = PPC::SELECT_CC_F4; else if (N->getValueType(0) == MVT::f64) SelectCCOp = PPC::SELECT_CC_F8; else SelectCCOp = PPC::SELECT_CC_VRRC; SDValue Ops[] = { CCReg, N->getOperand(2), N->getOperand(3), getI32Imm(BROpc) }; return CurDAG->SelectNodeTo(N, SelectCCOp, N->getValueType(0), Ops, 4); } case PPCISD::COND_BRANCH: { // Op #0 is the Chain. // Op #1 is the PPC::PRED_* number. // Op #2 is the CR# // Op #3 is the Dest MBB // Op #4 is the Flag. // Prevent PPC::PRED_* from being selected into LI. SDValue Pred = getI32Imm(cast(N->getOperand(1))->getZExtValue()); SDValue Ops[] = { Pred, N->getOperand(2), N->getOperand(3), N->getOperand(0), N->getOperand(4) }; return CurDAG->SelectNodeTo(N, PPC::BCC, MVT::Other, Ops, 5); } case ISD::BR_CC: { ISD::CondCode CC = cast(N->getOperand(1))->get(); SDValue CondCode = SelectCC(N->getOperand(2), N->getOperand(3), CC, dl); SDValue Ops[] = { getI32Imm(getPredicateForSetCC(CC)), CondCode, N->getOperand(4), N->getOperand(0) }; return CurDAG->SelectNodeTo(N, PPC::BCC, MVT::Other, Ops, 4); } case ISD::BRIND: { // FIXME: Should custom lower this. SDValue Chain = N->getOperand(0); SDValue Target = N->getOperand(1); unsigned Opc = Target.getValueType() == MVT::i32 ? PPC::MTCTR : PPC::MTCTR8; Chain = SDValue(CurDAG->getTargetNode(Opc, dl, MVT::Other, Target, Chain), 0); return CurDAG->SelectNodeTo(N, PPC::BCTR, MVT::Other, Chain); } case ISD::DECLARE: { SDValue Chain = N->getOperand(0); SDValue N1 = N->getOperand(1); SDValue N2 = N->getOperand(2); FrameIndexSDNode *FINode = dyn_cast(N1); // FIXME: We need to handle this for VLAs. if (!FINode) { ReplaceUses(Op.getValue(0), Chain); return NULL; } if (N2.getOpcode() == ISD::ADD) { if (N2.getOperand(0).getOpcode() == ISD::ADD && N2.getOperand(0).getOperand(0).getOpcode() == PPCISD::GlobalBaseReg && N2.getOperand(0).getOperand(1).getOpcode() == PPCISD::Hi && N2.getOperand(1).getOpcode() == PPCISD::Lo) N2 = N2.getOperand(0).getOperand(1).getOperand(0); else if (N2.getOperand(0).getOpcode() == ISD::ADD && N2.getOperand(0).getOperand(0).getOpcode() == PPCISD::GlobalBaseReg && N2.getOperand(0).getOperand(1).getOpcode() == PPCISD::Lo && N2.getOperand(1).getOpcode() == PPCISD::Hi) N2 = N2.getOperand(0).getOperand(1).getOperand(0); else if (N2.getOperand(0).getOpcode() == PPCISD::Hi && N2.getOperand(1).getOpcode() == PPCISD::Lo) N2 = N2.getOperand(0).getOperand(0); } // If we don't have a global address here, the debug info is mangled, just // drop it. if (!isa(N2)) { ReplaceUses(Op.getValue(0), Chain); return NULL; } int FI = cast(N1)->getIndex(); GlobalValue *GV = cast(N2)->getGlobal(); SDValue Tmp1 = CurDAG->getTargetFrameIndex(FI, TLI.getPointerTy()); SDValue Tmp2 = CurDAG->getTargetGlobalAddress(GV, TLI.getPointerTy()); return CurDAG->SelectNodeTo(N, TargetInstrInfo::DECLARE, MVT::Other, Tmp1, Tmp2, Chain); } } return SelectCode(Op); } /// createPPCISelDag - This pass converts a legalized DAG into a /// PowerPC-specific DAG, ready for instruction scheduling. /// FunctionPass *llvm::createPPCISelDag(PPCTargetMachine &TM) { return new PPCDAGToDAGISel(TM); }