| //===- HexagonConstExtenders.cpp ------------------------------------------===// | 
 | // | 
 | // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. | 
 | // See https://llvm.org/LICENSE.txt for license information. | 
 | // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception | 
 | // | 
 | //===----------------------------------------------------------------------===// | 
 |  | 
 | #include "HexagonInstrInfo.h" | 
 | #include "HexagonRegisterInfo.h" | 
 | #include "HexagonSubtarget.h" | 
 | #include "llvm/ADT/SetVector.h" | 
 | #include "llvm/ADT/SmallVector.h" | 
 | #include "llvm/CodeGen/MachineDominators.h" | 
 | #include "llvm/CodeGen/MachineFunctionPass.h" | 
 | #include "llvm/CodeGen/MachineInstrBuilder.h" | 
 | #include "llvm/CodeGen/MachineRegisterInfo.h" | 
 | #include "llvm/CodeGen/Register.h" | 
 | #include "llvm/InitializePasses.h" | 
 | #include "llvm/Pass.h" | 
 | #include "llvm/Support/CommandLine.h" | 
 | #include "llvm/Support/raw_ostream.h" | 
 | #include <map> | 
 | #include <set> | 
 | #include <utility> | 
 | #include <vector> | 
 |  | 
 | #define DEBUG_TYPE "hexagon-cext-opt" | 
 |  | 
 | using namespace llvm; | 
 |  | 
 | static cl::opt<unsigned> CountThreshold( | 
 |     "hexagon-cext-threshold", cl::init(3), cl::Hidden, | 
 |     cl::desc("Minimum number of extenders to trigger replacement")); | 
 |  | 
 | static cl::opt<unsigned> | 
 |     ReplaceLimit("hexagon-cext-limit", cl::init(0), cl::Hidden, | 
 |                  cl::desc("Maximum number of replacements")); | 
 |  | 
 | namespace llvm { | 
 |   void initializeHexagonConstExtendersPass(PassRegistry&); | 
 |   FunctionPass *createHexagonConstExtenders(); | 
 | } | 
 |  | 
 | static int32_t adjustUp(int32_t V, uint8_t A, uint8_t O) { | 
 |   assert(isPowerOf2_32(A)); | 
 |   int32_t U = (V & -A) + O; | 
 |   return U >= V ? U : U+A; | 
 | } | 
 |  | 
 | static int32_t adjustDown(int32_t V, uint8_t A, uint8_t O) { | 
 |   assert(isPowerOf2_32(A)); | 
 |   int32_t U = (V & -A) + O; | 
 |   return U <= V ? U : U-A; | 
 | } | 
 |  | 
 | namespace { | 
 |   struct OffsetRange { | 
 |     // The range of values between Min and Max that are of form Align*N+Offset, | 
 |     // for some integer N. Min and Max are required to be of that form as well, | 
 |     // except in the case of an empty range. | 
 |     int32_t Min = INT_MIN, Max = INT_MAX; | 
 |     uint8_t Align = 1; | 
 |     uint8_t Offset = 0; | 
 |  | 
 |     OffsetRange() = default; | 
 |     OffsetRange(int32_t L, int32_t H, uint8_t A, uint8_t O = 0) | 
 |       : Min(L), Max(H), Align(A), Offset(O) {} | 
 |     OffsetRange &intersect(OffsetRange A) { | 
 |       if (Align < A.Align) | 
 |         std::swap(*this, A); | 
 |  | 
 |       // Align >= A.Align. | 
 |       if (Offset >= A.Offset && (Offset - A.Offset) % A.Align == 0) { | 
 |         Min = adjustUp(std::max(Min, A.Min), Align, Offset); | 
 |         Max = adjustDown(std::min(Max, A.Max), Align, Offset); | 
 |       } else { | 
 |         // Make an empty range. | 
 |         Min = 0; | 
 |         Max = -1; | 
 |       } | 
 |       // Canonicalize empty ranges. | 
 |       if (Min > Max) | 
 |         std::tie(Min, Max, Align) = std::make_tuple(0, -1, 1); | 
 |       return *this; | 
 |     } | 
 |     OffsetRange &shift(int32_t S) { | 
 |       Min += S; | 
 |       Max += S; | 
 |       Offset = (Offset+S) % Align; | 
 |       return *this; | 
 |     } | 
 |     OffsetRange &extendBy(int32_t D) { | 
 |       // If D < 0, extend Min, otherwise extend Max. | 
 |       assert(D % Align == 0); | 
 |       if (D < 0) | 
 |         Min = (INT_MIN-D < Min) ? Min+D : INT_MIN; | 
 |       else | 
 |         Max = (INT_MAX-D > Max) ? Max+D : INT_MAX; | 
 |       return *this; | 
 |     } | 
 |     bool empty() const { | 
 |       return Min > Max; | 
 |     } | 
 |     bool contains(int32_t V) const { | 
 |       return Min <= V && V <= Max && (V-Offset) % Align == 0; | 
 |     } | 
 |     bool operator==(const OffsetRange &R) const { | 
 |       return Min == R.Min && Max == R.Max && Align == R.Align; | 
 |     } | 
 |     bool operator!=(const OffsetRange &R) const { | 
 |       return !operator==(R); | 
 |     } | 
 |     bool operator<(const OffsetRange &R) const { | 
 |       if (Min != R.Min) | 
 |         return Min < R.Min; | 
 |       if (Max != R.Max) | 
 |         return Max < R.Max; | 
 |       return Align < R.Align; | 
 |     } | 
 |     static OffsetRange zero() { return {0, 0, 1}; } | 
 |   }; | 
 |  | 
 |   struct RangeTree { | 
 |     struct Node { | 
 |       Node(const OffsetRange &R) : MaxEnd(R.Max), Range(R) {} | 
 |       unsigned Height = 1; | 
 |       unsigned Count = 1; | 
 |       int32_t MaxEnd; | 
 |       const OffsetRange &Range; | 
 |       Node *Left = nullptr, *Right = nullptr; | 
 |     }; | 
 |  | 
 |     Node *Root = nullptr; | 
 |  | 
 |     void add(const OffsetRange &R) { | 
 |       Root = add(Root, R); | 
 |     } | 
 |     void erase(const Node *N) { | 
 |       Root = remove(Root, N); | 
 |       delete N; | 
 |     } | 
 |     void order(SmallVectorImpl<Node*> &Seq) const { | 
 |       order(Root, Seq); | 
 |     } | 
 |     SmallVector<Node*,8> nodesWith(int32_t P, bool CheckAlign = true) { | 
 |       SmallVector<Node*,8> Nodes; | 
 |       nodesWith(Root, P, CheckAlign, Nodes); | 
 |       return Nodes; | 
 |     } | 
 |     void dump() const; | 
 |     ~RangeTree() { | 
 |       SmallVector<Node*,8> Nodes; | 
 |       order(Nodes); | 
 |       for (Node *N : Nodes) | 
 |         delete N; | 
 |     } | 
 |  | 
 |   private: | 
 |     void dump(const Node *N) const; | 
 |     void order(Node *N, SmallVectorImpl<Node*> &Seq) const; | 
 |     void nodesWith(Node *N, int32_t P, bool CheckA, | 
 |                    SmallVectorImpl<Node*> &Seq) const; | 
 |  | 
 |     Node *add(Node *N, const OffsetRange &R); | 
 |     Node *remove(Node *N, const Node *D); | 
 |     Node *rotateLeft(Node *Lower, Node *Higher); | 
 |     Node *rotateRight(Node *Lower, Node *Higher); | 
 |     unsigned height(Node *N) { | 
 |       return N != nullptr ? N->Height : 0; | 
 |     } | 
 |     Node *update(Node *N) { | 
 |       assert(N != nullptr); | 
 |       N->Height = 1 + std::max(height(N->Left), height(N->Right)); | 
 |       if (N->Left) | 
 |         N->MaxEnd = std::max(N->MaxEnd, N->Left->MaxEnd); | 
 |       if (N->Right) | 
 |         N->MaxEnd = std::max(N->MaxEnd, N->Right->MaxEnd); | 
 |       return N; | 
 |     } | 
 |     Node *rebalance(Node *N) { | 
 |       assert(N != nullptr); | 
 |       int32_t Balance = height(N->Right) - height(N->Left); | 
 |       if (Balance < -1) | 
 |         return rotateRight(N->Left, N); | 
 |       if (Balance > 1) | 
 |         return rotateLeft(N->Right, N); | 
 |       return N; | 
 |     } | 
 |   }; | 
 |  | 
 |   struct Loc { | 
 |     MachineBasicBlock *Block = nullptr; | 
 |     MachineBasicBlock::iterator At; | 
 |  | 
 |     Loc(MachineBasicBlock *B, MachineBasicBlock::iterator It) | 
 |       : Block(B), At(It) { | 
 |       if (B->end() == It) { | 
 |         Pos = -1; | 
 |       } else { | 
 |         assert(It->getParent() == B); | 
 |         Pos = std::distance(B->begin(), It); | 
 |       } | 
 |     } | 
 |     bool operator<(Loc A) const { | 
 |       if (Block != A.Block) | 
 |         return Block->getNumber() < A.Block->getNumber(); | 
 |       if (A.Pos == -1) | 
 |         return Pos != A.Pos; | 
 |       return Pos != -1 && Pos < A.Pos; | 
 |     } | 
 |   private: | 
 |     int Pos = 0; | 
 |   }; | 
 |  | 
 |   struct HexagonConstExtenders : public MachineFunctionPass { | 
 |     static char ID; | 
 |     HexagonConstExtenders() : MachineFunctionPass(ID) {} | 
 |  | 
 |     void getAnalysisUsage(AnalysisUsage &AU) const override { | 
 |       AU.addRequired<MachineDominatorTree>(); | 
 |       AU.addPreserved<MachineDominatorTree>(); | 
 |       MachineFunctionPass::getAnalysisUsage(AU); | 
 |     } | 
 |  | 
 |     StringRef getPassName() const override { | 
 |       return "Hexagon constant-extender optimization"; | 
 |     } | 
 |     bool runOnMachineFunction(MachineFunction &MF) override; | 
 |  | 
 |   private: | 
 |     struct Register { | 
 |       Register() = default; | 
 |       Register(llvm::Register R, unsigned S) : Reg(R), Sub(S) {} | 
 |       Register(const MachineOperand &Op) | 
 |         : Reg(Op.getReg()), Sub(Op.getSubReg()) {} | 
 |       Register &operator=(const MachineOperand &Op) { | 
 |         if (Op.isReg()) { | 
 |           Reg = Op.getReg(); | 
 |           Sub = Op.getSubReg(); | 
 |         } else if (Op.isFI()) { | 
 |           Reg = llvm::Register::index2StackSlot(Op.getIndex()); | 
 |         } | 
 |         return *this; | 
 |       } | 
 |       bool isVReg() const { | 
 |         return Reg != 0 && !Reg.isStack() && Reg.isVirtual(); | 
 |       } | 
 |       bool isSlot() const { return Reg != 0 && Reg.isStack(); } | 
 |       operator MachineOperand() const { | 
 |         if (isVReg()) | 
 |           return MachineOperand::CreateReg(Reg, /*Def*/false, /*Imp*/false, | 
 |                           /*Kill*/false, /*Dead*/false, /*Undef*/false, | 
 |                           /*EarlyClobber*/false, Sub); | 
 |         if (Reg.isStack()) { | 
 |           int FI = llvm::Register::stackSlot2Index(Reg); | 
 |           return MachineOperand::CreateFI(FI); | 
 |         } | 
 |         llvm_unreachable("Cannot create MachineOperand"); | 
 |       } | 
 |       bool operator==(Register R) const { return Reg == R.Reg && Sub == R.Sub; } | 
 |       bool operator!=(Register R) const { return !operator==(R); } | 
 |       bool operator<(Register R) const { | 
 |         // For std::map. | 
 |         return Reg < R.Reg || (Reg == R.Reg && Sub < R.Sub); | 
 |       } | 
 |       llvm::Register Reg; | 
 |       unsigned Sub = 0; | 
 |     }; | 
 |  | 
 |     struct ExtExpr { | 
 |       // A subexpression in which the extender is used. In general, this | 
 |       // represents an expression where adding D to the extender will be | 
 |       // equivalent to adding D to the expression as a whole. In other | 
 |       // words, expr(add(##V,D) = add(expr(##V),D). | 
 |  | 
 |       // The original motivation for this are the io/ur addressing modes, | 
 |       // where the offset is extended. Consider the io example: | 
 |       // In memw(Rs+##V), the ##V could be replaced by a register Rt to | 
 |       // form the rr mode: memw(Rt+Rs<<0). In such case, however, the | 
 |       // register Rt must have exactly the value of ##V. If there was | 
 |       // another instruction memw(Rs+##V+4), it would need a different Rt. | 
 |       // Now, if Rt was initialized as "##V+Rs<<0", both of these | 
 |       // instructions could use the same Rt, just with different offsets. | 
 |       // Here it's clear that "initializer+4" should be the same as if | 
 |       // the offset 4 was added to the ##V in the initializer. | 
 |  | 
 |       // The only kinds of expressions that support the requirement of | 
 |       // commuting with addition are addition and subtraction from ##V. | 
 |       // Include shifting the Rs to account for the ur addressing mode: | 
 |       //   ##Val + Rs << S | 
 |       //   ##Val - Rs | 
 |       Register Rs; | 
 |       unsigned S = 0; | 
 |       bool Neg = false; | 
 |  | 
 |       ExtExpr() = default; | 
 |       ExtExpr(Register RS, bool NG, unsigned SH) : Rs(RS), S(SH), Neg(NG) {} | 
 |       // Expression is trivial if it does not modify the extender. | 
 |       bool trivial() const { | 
 |         return Rs.Reg == 0; | 
 |       } | 
 |       bool operator==(const ExtExpr &Ex) const { | 
 |         return Rs == Ex.Rs && S == Ex.S && Neg == Ex.Neg; | 
 |       } | 
 |       bool operator!=(const ExtExpr &Ex) const { | 
 |         return !operator==(Ex); | 
 |       } | 
 |       bool operator<(const ExtExpr &Ex) const { | 
 |         if (Rs != Ex.Rs) | 
 |           return Rs < Ex.Rs; | 
 |         if (S != Ex.S) | 
 |           return S < Ex.S; | 
 |         return !Neg && Ex.Neg; | 
 |       } | 
 |     }; | 
 |  | 
 |     struct ExtDesc { | 
 |       MachineInstr *UseMI = nullptr; | 
 |       unsigned OpNum = -1u; | 
 |       // The subexpression in which the extender is used (e.g. address | 
 |       // computation). | 
 |       ExtExpr Expr; | 
 |       // Optional register that is assigned the value of Expr. | 
 |       Register Rd; | 
 |       // Def means that the output of the instruction may differ from the | 
 |       // original by a constant c, and that the difference can be corrected | 
 |       // by adding/subtracting c in all users of the defined register. | 
 |       bool IsDef = false; | 
 |  | 
 |       MachineOperand &getOp() { | 
 |         return UseMI->getOperand(OpNum); | 
 |       } | 
 |       const MachineOperand &getOp() const { | 
 |         return UseMI->getOperand(OpNum); | 
 |       } | 
 |     }; | 
 |  | 
 |     struct ExtRoot { | 
 |       union { | 
 |         const ConstantFP *CFP;  // MO_FPImmediate | 
 |         const char *SymbolName; // MO_ExternalSymbol | 
 |         const GlobalValue *GV;  // MO_GlobalAddress | 
 |         const BlockAddress *BA; // MO_BlockAddress | 
 |         int64_t ImmVal;         // MO_Immediate, MO_TargetIndex, | 
 |                                 // and MO_ConstantPoolIndex | 
 |       } V; | 
 |       unsigned Kind;            // Same as in MachineOperand. | 
 |       unsigned char TF;         // TargetFlags. | 
 |  | 
 |       ExtRoot(const MachineOperand &Op); | 
 |       bool operator==(const ExtRoot &ER) const { | 
 |         return Kind == ER.Kind && V.ImmVal == ER.V.ImmVal; | 
 |       } | 
 |       bool operator!=(const ExtRoot &ER) const { | 
 |         return !operator==(ER); | 
 |       } | 
 |       bool operator<(const ExtRoot &ER) const; | 
 |     }; | 
 |  | 
 |     struct ExtValue : public ExtRoot { | 
 |       int32_t Offset; | 
 |  | 
 |       ExtValue(const MachineOperand &Op); | 
 |       ExtValue(const ExtDesc &ED) : ExtValue(ED.getOp()) {} | 
 |       ExtValue(const ExtRoot &ER, int32_t Off) : ExtRoot(ER), Offset(Off) {} | 
 |       bool operator<(const ExtValue &EV) const; | 
 |       bool operator==(const ExtValue &EV) const { | 
 |         return ExtRoot(*this) == ExtRoot(EV) && Offset == EV.Offset; | 
 |       } | 
 |       bool operator!=(const ExtValue &EV) const { | 
 |         return !operator==(EV); | 
 |       } | 
 |       explicit operator MachineOperand() const; | 
 |     }; | 
 |  | 
 |     using IndexList = SetVector<unsigned>; | 
 |     using ExtenderInit = std::pair<ExtValue, ExtExpr>; | 
 |     using AssignmentMap = std::map<ExtenderInit, IndexList>; | 
 |     using LocDefList = std::vector<std::pair<Loc, IndexList>>; | 
 |  | 
 |     const HexagonSubtarget *HST = nullptr; | 
 |     const HexagonInstrInfo *HII = nullptr; | 
 |     const HexagonRegisterInfo *HRI = nullptr; | 
 |     MachineDominatorTree *MDT = nullptr; | 
 |     MachineRegisterInfo *MRI = nullptr; | 
 |     std::vector<ExtDesc> Extenders; | 
 |     std::vector<unsigned> NewRegs; | 
 |  | 
 |     bool isStoreImmediate(unsigned Opc) const; | 
 |     bool isRegOffOpcode(unsigned ExtOpc) const ; | 
 |     unsigned getRegOffOpcode(unsigned ExtOpc) const; | 
 |     unsigned getDirectRegReplacement(unsigned ExtOpc) const; | 
 |     OffsetRange getOffsetRange(Register R, const MachineInstr &MI) const; | 
 |     OffsetRange getOffsetRange(const ExtDesc &ED) const; | 
 |     OffsetRange getOffsetRange(Register Rd) const; | 
 |  | 
 |     void recordExtender(MachineInstr &MI, unsigned OpNum); | 
 |     void collectInstr(MachineInstr &MI); | 
 |     void collect(MachineFunction &MF); | 
 |     void assignInits(const ExtRoot &ER, unsigned Begin, unsigned End, | 
 |                      AssignmentMap &IMap); | 
 |     void calculatePlacement(const ExtenderInit &ExtI, const IndexList &Refs, | 
 |                             LocDefList &Defs); | 
 |     Register insertInitializer(Loc DefL, const ExtenderInit &ExtI); | 
 |     bool replaceInstrExact(const ExtDesc &ED, Register ExtR); | 
 |     bool replaceInstrExpr(const ExtDesc &ED, const ExtenderInit &ExtI, | 
 |                           Register ExtR, int32_t &Diff); | 
 |     bool replaceInstr(unsigned Idx, Register ExtR, const ExtenderInit &ExtI); | 
 |     bool replaceExtenders(const AssignmentMap &IMap); | 
 |  | 
 |     unsigned getOperandIndex(const MachineInstr &MI, | 
 |                              const MachineOperand &Op) const; | 
 |     const MachineOperand &getPredicateOp(const MachineInstr &MI) const; | 
 |     const MachineOperand &getLoadResultOp(const MachineInstr &MI) const; | 
 |     const MachineOperand &getStoredValueOp(const MachineInstr &MI) const; | 
 |  | 
 |     friend struct PrintRegister; | 
 |     friend struct PrintExpr; | 
 |     friend struct PrintInit; | 
 |     friend struct PrintIMap; | 
 |     friend raw_ostream &operator<< (raw_ostream &OS, | 
 |                                     const struct PrintRegister &P); | 
 |     friend raw_ostream &operator<< (raw_ostream &OS, const struct PrintExpr &P); | 
 |     friend raw_ostream &operator<< (raw_ostream &OS, const struct PrintInit &P); | 
 |     friend raw_ostream &operator<< (raw_ostream &OS, const ExtDesc &ED); | 
 |     friend raw_ostream &operator<< (raw_ostream &OS, const ExtRoot &ER); | 
 |     friend raw_ostream &operator<< (raw_ostream &OS, const ExtValue &EV); | 
 |     friend raw_ostream &operator<< (raw_ostream &OS, const OffsetRange &OR); | 
 |     friend raw_ostream &operator<< (raw_ostream &OS, const struct PrintIMap &P); | 
 |   }; | 
 |  | 
 |   using HCE = HexagonConstExtenders; | 
 |  | 
 |   LLVM_ATTRIBUTE_UNUSED | 
 |   raw_ostream &operator<< (raw_ostream &OS, const OffsetRange &OR) { | 
 |     if (OR.Min > OR.Max) | 
 |       OS << '!'; | 
 |     OS << '[' << OR.Min << ',' << OR.Max << "]a" << unsigned(OR.Align) | 
 |        << '+' << unsigned(OR.Offset); | 
 |     return OS; | 
 |   } | 
 |  | 
 |   struct PrintRegister { | 
 |     PrintRegister(HCE::Register R, const HexagonRegisterInfo &I) | 
 |       : Rs(R), HRI(I) {} | 
 |     HCE::Register Rs; | 
 |     const HexagonRegisterInfo &HRI; | 
 |   }; | 
 |  | 
 |   LLVM_ATTRIBUTE_UNUSED | 
 |   raw_ostream &operator<< (raw_ostream &OS, const PrintRegister &P) { | 
 |     if (P.Rs.Reg != 0) | 
 |       OS << printReg(P.Rs.Reg, &P.HRI, P.Rs.Sub); | 
 |     else | 
 |       OS << "noreg"; | 
 |     return OS; | 
 |   } | 
 |  | 
 |   struct PrintExpr { | 
 |     PrintExpr(const HCE::ExtExpr &E, const HexagonRegisterInfo &I) | 
 |       : Ex(E), HRI(I) {} | 
 |     const HCE::ExtExpr &Ex; | 
 |     const HexagonRegisterInfo &HRI; | 
 |   }; | 
 |  | 
 |   LLVM_ATTRIBUTE_UNUSED | 
 |   raw_ostream &operator<< (raw_ostream &OS, const PrintExpr &P) { | 
 |     OS << "## " << (P.Ex.Neg ? "- " : "+ "); | 
 |     if (P.Ex.Rs.Reg != 0) | 
 |       OS << printReg(P.Ex.Rs.Reg, &P.HRI, P.Ex.Rs.Sub); | 
 |     else | 
 |       OS << "__"; | 
 |     OS << " << " << P.Ex.S; | 
 |     return OS; | 
 |   } | 
 |  | 
 |   struct PrintInit { | 
 |     PrintInit(const HCE::ExtenderInit &EI, const HexagonRegisterInfo &I) | 
 |       : ExtI(EI), HRI(I) {} | 
 |     const HCE::ExtenderInit &ExtI; | 
 |     const HexagonRegisterInfo &HRI; | 
 |   }; | 
 |  | 
 |   LLVM_ATTRIBUTE_UNUSED | 
 |   raw_ostream &operator<< (raw_ostream &OS, const PrintInit &P) { | 
 |     OS << '[' << P.ExtI.first << ", " | 
 |        << PrintExpr(P.ExtI.second, P.HRI) << ']'; | 
 |     return OS; | 
 |   } | 
 |  | 
 |   LLVM_ATTRIBUTE_UNUSED | 
 |   raw_ostream &operator<< (raw_ostream &OS, const HCE::ExtDesc &ED) { | 
 |     assert(ED.OpNum != -1u); | 
 |     const MachineBasicBlock &MBB = *ED.getOp().getParent()->getParent(); | 
 |     const MachineFunction &MF = *MBB.getParent(); | 
 |     const auto &HRI = *MF.getSubtarget<HexagonSubtarget>().getRegisterInfo(); | 
 |     OS << "bb#" << MBB.getNumber() << ": "; | 
 |     if (ED.Rd.Reg != 0) | 
 |       OS << printReg(ED.Rd.Reg, &HRI, ED.Rd.Sub); | 
 |     else | 
 |       OS << "__"; | 
 |     OS << " = " << PrintExpr(ED.Expr, HRI); | 
 |     if (ED.IsDef) | 
 |       OS << ", def"; | 
 |     return OS; | 
 |   } | 
 |  | 
 |   LLVM_ATTRIBUTE_UNUSED | 
 |   raw_ostream &operator<< (raw_ostream &OS, const HCE::ExtRoot &ER) { | 
 |     switch (ER.Kind) { | 
 |       case MachineOperand::MO_Immediate: | 
 |         OS << "imm:" << ER.V.ImmVal; | 
 |         break; | 
 |       case MachineOperand::MO_FPImmediate: | 
 |         OS << "fpi:" << *ER.V.CFP; | 
 |         break; | 
 |       case MachineOperand::MO_ExternalSymbol: | 
 |         OS << "sym:" << *ER.V.SymbolName; | 
 |         break; | 
 |       case MachineOperand::MO_GlobalAddress: | 
 |         OS << "gad:" << ER.V.GV->getName(); | 
 |         break; | 
 |       case MachineOperand::MO_BlockAddress: | 
 |         OS << "blk:" << *ER.V.BA; | 
 |         break; | 
 |       case MachineOperand::MO_TargetIndex: | 
 |         OS << "tgi:" << ER.V.ImmVal; | 
 |         break; | 
 |       case MachineOperand::MO_ConstantPoolIndex: | 
 |         OS << "cpi:" << ER.V.ImmVal; | 
 |         break; | 
 |       case MachineOperand::MO_JumpTableIndex: | 
 |         OS << "jti:" << ER.V.ImmVal; | 
 |         break; | 
 |       default: | 
 |         OS << "???:" << ER.V.ImmVal; | 
 |         break; | 
 |     } | 
 |     return OS; | 
 |   } | 
 |  | 
 |   LLVM_ATTRIBUTE_UNUSED | 
 |   raw_ostream &operator<< (raw_ostream &OS, const HCE::ExtValue &EV) { | 
 |     OS << HCE::ExtRoot(EV) << "  off:" << EV.Offset; | 
 |     return OS; | 
 |   } | 
 |  | 
 |   struct PrintIMap { | 
 |     PrintIMap(const HCE::AssignmentMap &M, const HexagonRegisterInfo &I) | 
 |       : IMap(M), HRI(I) {} | 
 |     const HCE::AssignmentMap &IMap; | 
 |     const HexagonRegisterInfo &HRI; | 
 |   }; | 
 |  | 
 |   LLVM_ATTRIBUTE_UNUSED | 
 |   raw_ostream &operator<< (raw_ostream &OS, const PrintIMap &P) { | 
 |     OS << "{\n"; | 
 |     for (const std::pair<const HCE::ExtenderInit, HCE::IndexList> &Q : P.IMap) { | 
 |       OS << "  " << PrintInit(Q.first, P.HRI) << " -> {"; | 
 |       for (unsigned I : Q.second) | 
 |         OS << ' ' << I; | 
 |       OS << " }\n"; | 
 |     } | 
 |     OS << "}\n"; | 
 |     return OS; | 
 |   } | 
 | } | 
 |  | 
 | INITIALIZE_PASS_BEGIN(HexagonConstExtenders, "hexagon-cext-opt", | 
 |       "Hexagon constant-extender optimization", false, false) | 
 | INITIALIZE_PASS_DEPENDENCY(MachineDominatorTree) | 
 | INITIALIZE_PASS_END(HexagonConstExtenders, "hexagon-cext-opt", | 
 |       "Hexagon constant-extender optimization", false, false) | 
 |  | 
 | static unsigned ReplaceCounter = 0; | 
 |  | 
 | char HCE::ID = 0; | 
 |  | 
 | #ifndef NDEBUG | 
 | LLVM_DUMP_METHOD void RangeTree::dump() const { | 
 |   dbgs() << "Root: " << Root << '\n'; | 
 |   if (Root) | 
 |     dump(Root); | 
 | } | 
 |  | 
 | LLVM_DUMP_METHOD void RangeTree::dump(const Node *N) const { | 
 |   dbgs() << "Node: " << N << '\n'; | 
 |   dbgs() << "  Height: " << N->Height << '\n'; | 
 |   dbgs() << "  Count: " << N->Count << '\n'; | 
 |   dbgs() << "  MaxEnd: " << N->MaxEnd << '\n'; | 
 |   dbgs() << "  Range: " << N->Range << '\n'; | 
 |   dbgs() << "  Left: " << N->Left << '\n'; | 
 |   dbgs() << "  Right: " << N->Right << "\n\n"; | 
 |  | 
 |   if (N->Left) | 
 |     dump(N->Left); | 
 |   if (N->Right) | 
 |     dump(N->Right); | 
 | } | 
 | #endif | 
 |  | 
 | void RangeTree::order(Node *N, SmallVectorImpl<Node*> &Seq) const { | 
 |   if (N == nullptr) | 
 |     return; | 
 |   order(N->Left, Seq); | 
 |   Seq.push_back(N); | 
 |   order(N->Right, Seq); | 
 | } | 
 |  | 
 | void RangeTree::nodesWith(Node *N, int32_t P, bool CheckA, | 
 |       SmallVectorImpl<Node*> &Seq) const { | 
 |   if (N == nullptr || N->MaxEnd < P) | 
 |     return; | 
 |   nodesWith(N->Left, P, CheckA, Seq); | 
 |   if (N->Range.Min <= P) { | 
 |     if ((CheckA && N->Range.contains(P)) || (!CheckA && P <= N->Range.Max)) | 
 |       Seq.push_back(N); | 
 |     nodesWith(N->Right, P, CheckA, Seq); | 
 |   } | 
 | } | 
 |  | 
 | RangeTree::Node *RangeTree::add(Node *N, const OffsetRange &R) { | 
 |   if (N == nullptr) | 
 |     return new Node(R); | 
 |  | 
 |   if (N->Range == R) { | 
 |     N->Count++; | 
 |     return N; | 
 |   } | 
 |  | 
 |   if (R < N->Range) | 
 |     N->Left = add(N->Left, R); | 
 |   else | 
 |     N->Right = add(N->Right, R); | 
 |   return rebalance(update(N)); | 
 | } | 
 |  | 
 | RangeTree::Node *RangeTree::remove(Node *N, const Node *D) { | 
 |   assert(N != nullptr); | 
 |  | 
 |   if (N != D) { | 
 |     assert(N->Range != D->Range && "N and D should not be equal"); | 
 |     if (D->Range < N->Range) | 
 |       N->Left = remove(N->Left, D); | 
 |     else | 
 |       N->Right = remove(N->Right, D); | 
 |     return rebalance(update(N)); | 
 |   } | 
 |  | 
 |   // We got to the node we need to remove. If any of its children are | 
 |   // missing, simply replace it with the other child. | 
 |   if (N->Left == nullptr || N->Right == nullptr) | 
 |     return (N->Left == nullptr) ? N->Right : N->Left; | 
 |  | 
 |   // Find the rightmost child of N->Left, remove it and plug it in place | 
 |   // of N. | 
 |   Node *M = N->Left; | 
 |   while (M->Right) | 
 |     M = M->Right; | 
 |   M->Left = remove(N->Left, M); | 
 |   M->Right = N->Right; | 
 |   return rebalance(update(M)); | 
 | } | 
 |  | 
 | RangeTree::Node *RangeTree::rotateLeft(Node *Lower, Node *Higher) { | 
 |   assert(Higher->Right == Lower); | 
 |   // The Lower node is on the right from Higher. Make sure that Lower's | 
 |   // balance is greater to the right. Otherwise the rotation will create | 
 |   // an unbalanced tree again. | 
 |   if (height(Lower->Left) > height(Lower->Right)) | 
 |     Lower = rotateRight(Lower->Left, Lower); | 
 |   assert(height(Lower->Left) <= height(Lower->Right)); | 
 |   Higher->Right = Lower->Left; | 
 |   update(Higher); | 
 |   Lower->Left = Higher; | 
 |   update(Lower); | 
 |   return Lower; | 
 | } | 
 |  | 
 | RangeTree::Node *RangeTree::rotateRight(Node *Lower, Node *Higher) { | 
 |   assert(Higher->Left == Lower); | 
 |   // The Lower node is on the left from Higher. Make sure that Lower's | 
 |   // balance is greater to the left. Otherwise the rotation will create | 
 |   // an unbalanced tree again. | 
 |   if (height(Lower->Left) < height(Lower->Right)) | 
 |     Lower = rotateLeft(Lower->Right, Lower); | 
 |   assert(height(Lower->Left) >= height(Lower->Right)); | 
 |   Higher->Left = Lower->Right; | 
 |   update(Higher); | 
 |   Lower->Right = Higher; | 
 |   update(Lower); | 
 |   return Lower; | 
 | } | 
 |  | 
 |  | 
 | HCE::ExtRoot::ExtRoot(const MachineOperand &Op) { | 
 |   // Always store ImmVal, since it's the field used for comparisons. | 
 |   V.ImmVal = 0; | 
 |   if (Op.isImm()) | 
 |     ; // Keep 0. Do not use Op.getImm() for value here (treat 0 as the root). | 
 |   else if (Op.isFPImm()) | 
 |     V.CFP = Op.getFPImm(); | 
 |   else if (Op.isSymbol()) | 
 |     V.SymbolName = Op.getSymbolName(); | 
 |   else if (Op.isGlobal()) | 
 |     V.GV = Op.getGlobal(); | 
 |   else if (Op.isBlockAddress()) | 
 |     V.BA = Op.getBlockAddress(); | 
 |   else if (Op.isCPI() || Op.isTargetIndex() || Op.isJTI()) | 
 |     V.ImmVal = Op.getIndex(); | 
 |   else | 
 |     llvm_unreachable("Unexpected operand type"); | 
 |  | 
 |   Kind = Op.getType(); | 
 |   TF = Op.getTargetFlags(); | 
 | } | 
 |  | 
 | bool HCE::ExtRoot::operator< (const HCE::ExtRoot &ER) const { | 
 |   if (Kind != ER.Kind) | 
 |     return Kind < ER.Kind; | 
 |   switch (Kind) { | 
 |     case MachineOperand::MO_Immediate: | 
 |     case MachineOperand::MO_TargetIndex: | 
 |     case MachineOperand::MO_ConstantPoolIndex: | 
 |     case MachineOperand::MO_JumpTableIndex: | 
 |       return V.ImmVal < ER.V.ImmVal; | 
 |     case MachineOperand::MO_FPImmediate: { | 
 |       const APFloat &ThisF = V.CFP->getValueAPF(); | 
 |       const APFloat &OtherF = ER.V.CFP->getValueAPF(); | 
 |       return ThisF.bitcastToAPInt().ult(OtherF.bitcastToAPInt()); | 
 |     } | 
 |     case MachineOperand::MO_ExternalSymbol: | 
 |       return StringRef(V.SymbolName) < StringRef(ER.V.SymbolName); | 
 |     case MachineOperand::MO_GlobalAddress: | 
 |       // Do not use GUIDs, since they depend on the source path. Moving the | 
 |       // source file to a different directory could cause different GUID | 
 |       // values for a pair of given symbols. These symbols could then compare | 
 |       // "less" in one directory, but "greater" in another. | 
 |       assert(!V.GV->getName().empty() && !ER.V.GV->getName().empty()); | 
 |       return V.GV->getName() < ER.V.GV->getName(); | 
 |     case MachineOperand::MO_BlockAddress: { | 
 |       const BasicBlock *ThisB = V.BA->getBasicBlock(); | 
 |       const BasicBlock *OtherB = ER.V.BA->getBasicBlock(); | 
 |       assert(ThisB->getParent() == OtherB->getParent()); | 
 |       const Function &F = *ThisB->getParent(); | 
 |       return std::distance(F.begin(), ThisB->getIterator()) < | 
 |              std::distance(F.begin(), OtherB->getIterator()); | 
 |     } | 
 |   } | 
 |   return V.ImmVal < ER.V.ImmVal; | 
 | } | 
 |  | 
 | HCE::ExtValue::ExtValue(const MachineOperand &Op) : ExtRoot(Op) { | 
 |   if (Op.isImm()) | 
 |     Offset = Op.getImm(); | 
 |   else if (Op.isFPImm() || Op.isJTI()) | 
 |     Offset = 0; | 
 |   else if (Op.isSymbol() || Op.isGlobal() || Op.isBlockAddress() || | 
 |            Op.isCPI() || Op.isTargetIndex()) | 
 |     Offset = Op.getOffset(); | 
 |   else | 
 |     llvm_unreachable("Unexpected operand type"); | 
 | } | 
 |  | 
 | bool HCE::ExtValue::operator< (const HCE::ExtValue &EV) const { | 
 |   const ExtRoot &ER = *this; | 
 |   if (!(ER == ExtRoot(EV))) | 
 |     return ER < EV; | 
 |   return Offset < EV.Offset; | 
 | } | 
 |  | 
 | HCE::ExtValue::operator MachineOperand() const { | 
 |   switch (Kind) { | 
 |     case MachineOperand::MO_Immediate: | 
 |       return MachineOperand::CreateImm(V.ImmVal + Offset); | 
 |     case MachineOperand::MO_FPImmediate: | 
 |       assert(Offset == 0); | 
 |       return MachineOperand::CreateFPImm(V.CFP); | 
 |     case MachineOperand::MO_ExternalSymbol: | 
 |       assert(Offset == 0); | 
 |       return MachineOperand::CreateES(V.SymbolName, TF); | 
 |     case MachineOperand::MO_GlobalAddress: | 
 |       return MachineOperand::CreateGA(V.GV, Offset, TF); | 
 |     case MachineOperand::MO_BlockAddress: | 
 |       return MachineOperand::CreateBA(V.BA, Offset, TF); | 
 |     case MachineOperand::MO_TargetIndex: | 
 |       return MachineOperand::CreateTargetIndex(V.ImmVal, Offset, TF); | 
 |     case MachineOperand::MO_ConstantPoolIndex: | 
 |       return MachineOperand::CreateCPI(V.ImmVal, Offset, TF); | 
 |     case MachineOperand::MO_JumpTableIndex: | 
 |       assert(Offset == 0); | 
 |       return MachineOperand::CreateJTI(V.ImmVal, TF); | 
 |     default: | 
 |       llvm_unreachable("Unhandled kind"); | 
 |  } | 
 | } | 
 |  | 
 | bool HCE::isStoreImmediate(unsigned Opc) const { | 
 |   switch (Opc) { | 
 |     case Hexagon::S4_storeirbt_io: | 
 |     case Hexagon::S4_storeirbf_io: | 
 |     case Hexagon::S4_storeirht_io: | 
 |     case Hexagon::S4_storeirhf_io: | 
 |     case Hexagon::S4_storeirit_io: | 
 |     case Hexagon::S4_storeirif_io: | 
 |     case Hexagon::S4_storeirb_io: | 
 |     case Hexagon::S4_storeirh_io: | 
 |     case Hexagon::S4_storeiri_io: | 
 |       return true; | 
 |     default: | 
 |       break; | 
 |   } | 
 |   return false; | 
 | } | 
 |  | 
 | bool HCE::isRegOffOpcode(unsigned Opc) const { | 
 |   switch (Opc) { | 
 |     case Hexagon::L2_loadrub_io: | 
 |     case Hexagon::L2_loadrb_io: | 
 |     case Hexagon::L2_loadruh_io: | 
 |     case Hexagon::L2_loadrh_io: | 
 |     case Hexagon::L2_loadri_io: | 
 |     case Hexagon::L2_loadrd_io: | 
 |     case Hexagon::L2_loadbzw2_io: | 
 |     case Hexagon::L2_loadbzw4_io: | 
 |     case Hexagon::L2_loadbsw2_io: | 
 |     case Hexagon::L2_loadbsw4_io: | 
 |     case Hexagon::L2_loadalignh_io: | 
 |     case Hexagon::L2_loadalignb_io: | 
 |     case Hexagon::L2_ploadrubt_io: | 
 |     case Hexagon::L2_ploadrubf_io: | 
 |     case Hexagon::L2_ploadrbt_io: | 
 |     case Hexagon::L2_ploadrbf_io: | 
 |     case Hexagon::L2_ploadruht_io: | 
 |     case Hexagon::L2_ploadruhf_io: | 
 |     case Hexagon::L2_ploadrht_io: | 
 |     case Hexagon::L2_ploadrhf_io: | 
 |     case Hexagon::L2_ploadrit_io: | 
 |     case Hexagon::L2_ploadrif_io: | 
 |     case Hexagon::L2_ploadrdt_io: | 
 |     case Hexagon::L2_ploadrdf_io: | 
 |     case Hexagon::S2_storerb_io: | 
 |     case Hexagon::S2_storerh_io: | 
 |     case Hexagon::S2_storerf_io: | 
 |     case Hexagon::S2_storeri_io: | 
 |     case Hexagon::S2_storerd_io: | 
 |     case Hexagon::S2_pstorerbt_io: | 
 |     case Hexagon::S2_pstorerbf_io: | 
 |     case Hexagon::S2_pstorerht_io: | 
 |     case Hexagon::S2_pstorerhf_io: | 
 |     case Hexagon::S2_pstorerft_io: | 
 |     case Hexagon::S2_pstorerff_io: | 
 |     case Hexagon::S2_pstorerit_io: | 
 |     case Hexagon::S2_pstorerif_io: | 
 |     case Hexagon::S2_pstorerdt_io: | 
 |     case Hexagon::S2_pstorerdf_io: | 
 |     case Hexagon::A2_addi: | 
 |       return true; | 
 |     default: | 
 |       break; | 
 |   } | 
 |   return false; | 
 | } | 
 |  | 
 | unsigned HCE::getRegOffOpcode(unsigned ExtOpc) const { | 
 |   // If there exists an instruction that takes a register and offset, | 
 |   // that corresponds to the ExtOpc, return it, otherwise return 0. | 
 |   using namespace Hexagon; | 
 |   switch (ExtOpc) { | 
 |     case A2_tfrsi:    return A2_addi; | 
 |     default: | 
 |       break; | 
 |   } | 
 |   const MCInstrDesc &D = HII->get(ExtOpc); | 
 |   if (D.mayLoad() || D.mayStore()) { | 
 |     uint64_t F = D.TSFlags; | 
 |     unsigned AM = (F >> HexagonII::AddrModePos) & HexagonII::AddrModeMask; | 
 |     switch (AM) { | 
 |       case HexagonII::Absolute: | 
 |       case HexagonII::AbsoluteSet: | 
 |       case HexagonII::BaseLongOffset: | 
 |         switch (ExtOpc) { | 
 |           case PS_loadrubabs: | 
 |           case L4_loadrub_ap: | 
 |           case L4_loadrub_ur:     return L2_loadrub_io; | 
 |           case PS_loadrbabs: | 
 |           case L4_loadrb_ap: | 
 |           case L4_loadrb_ur:      return L2_loadrb_io; | 
 |           case PS_loadruhabs: | 
 |           case L4_loadruh_ap: | 
 |           case L4_loadruh_ur:     return L2_loadruh_io; | 
 |           case PS_loadrhabs: | 
 |           case L4_loadrh_ap: | 
 |           case L4_loadrh_ur:      return L2_loadrh_io; | 
 |           case PS_loadriabs: | 
 |           case L4_loadri_ap: | 
 |           case L4_loadri_ur:      return L2_loadri_io; | 
 |           case PS_loadrdabs: | 
 |           case L4_loadrd_ap: | 
 |           case L4_loadrd_ur:      return L2_loadrd_io; | 
 |           case L4_loadbzw2_ap: | 
 |           case L4_loadbzw2_ur:    return L2_loadbzw2_io; | 
 |           case L4_loadbzw4_ap: | 
 |           case L4_loadbzw4_ur:    return L2_loadbzw4_io; | 
 |           case L4_loadbsw2_ap: | 
 |           case L4_loadbsw2_ur:    return L2_loadbsw2_io; | 
 |           case L4_loadbsw4_ap: | 
 |           case L4_loadbsw4_ur:    return L2_loadbsw4_io; | 
 |           case L4_loadalignh_ap: | 
 |           case L4_loadalignh_ur:  return L2_loadalignh_io; | 
 |           case L4_loadalignb_ap: | 
 |           case L4_loadalignb_ur:  return L2_loadalignb_io; | 
 |           case L4_ploadrubt_abs:  return L2_ploadrubt_io; | 
 |           case L4_ploadrubf_abs:  return L2_ploadrubf_io; | 
 |           case L4_ploadrbt_abs:   return L2_ploadrbt_io; | 
 |           case L4_ploadrbf_abs:   return L2_ploadrbf_io; | 
 |           case L4_ploadruht_abs:  return L2_ploadruht_io; | 
 |           case L4_ploadruhf_abs:  return L2_ploadruhf_io; | 
 |           case L4_ploadrht_abs:   return L2_ploadrht_io; | 
 |           case L4_ploadrhf_abs:   return L2_ploadrhf_io; | 
 |           case L4_ploadrit_abs:   return L2_ploadrit_io; | 
 |           case L4_ploadrif_abs:   return L2_ploadrif_io; | 
 |           case L4_ploadrdt_abs:   return L2_ploadrdt_io; | 
 |           case L4_ploadrdf_abs:   return L2_ploadrdf_io; | 
 |           case PS_storerbabs: | 
 |           case S4_storerb_ap: | 
 |           case S4_storerb_ur:     return S2_storerb_io; | 
 |           case PS_storerhabs: | 
 |           case S4_storerh_ap: | 
 |           case S4_storerh_ur:     return S2_storerh_io; | 
 |           case PS_storerfabs: | 
 |           case S4_storerf_ap: | 
 |           case S4_storerf_ur:     return S2_storerf_io; | 
 |           case PS_storeriabs: | 
 |           case S4_storeri_ap: | 
 |           case S4_storeri_ur:     return S2_storeri_io; | 
 |           case PS_storerdabs: | 
 |           case S4_storerd_ap: | 
 |           case S4_storerd_ur:     return S2_storerd_io; | 
 |           case S4_pstorerbt_abs:  return S2_pstorerbt_io; | 
 |           case S4_pstorerbf_abs:  return S2_pstorerbf_io; | 
 |           case S4_pstorerht_abs:  return S2_pstorerht_io; | 
 |           case S4_pstorerhf_abs:  return S2_pstorerhf_io; | 
 |           case S4_pstorerft_abs:  return S2_pstorerft_io; | 
 |           case S4_pstorerff_abs:  return S2_pstorerff_io; | 
 |           case S4_pstorerit_abs:  return S2_pstorerit_io; | 
 |           case S4_pstorerif_abs:  return S2_pstorerif_io; | 
 |           case S4_pstorerdt_abs:  return S2_pstorerdt_io; | 
 |           case S4_pstorerdf_abs:  return S2_pstorerdf_io; | 
 |           default: | 
 |             break; | 
 |         } | 
 |         break; | 
 |       case HexagonII::BaseImmOffset: | 
 |         if (!isStoreImmediate(ExtOpc)) | 
 |           return ExtOpc; | 
 |         break; | 
 |       default: | 
 |         break; | 
 |     } | 
 |   } | 
 |   return 0; | 
 | } | 
 |  | 
 | unsigned HCE::getDirectRegReplacement(unsigned ExtOpc) const { | 
 |   switch (ExtOpc) { | 
 |     case Hexagon::A2_addi:          return Hexagon::A2_add; | 
 |     case Hexagon::A2_andir:         return Hexagon::A2_and; | 
 |     case Hexagon::A2_combineii:     return Hexagon::A4_combineri; | 
 |     case Hexagon::A2_orir:          return Hexagon::A2_or; | 
 |     case Hexagon::A2_paddif:        return Hexagon::A2_paddf; | 
 |     case Hexagon::A2_paddit:        return Hexagon::A2_paddt; | 
 |     case Hexagon::A2_subri:         return Hexagon::A2_sub; | 
 |     case Hexagon::A2_tfrsi:         return TargetOpcode::COPY; | 
 |     case Hexagon::A4_cmpbeqi:       return Hexagon::A4_cmpbeq; | 
 |     case Hexagon::A4_cmpbgti:       return Hexagon::A4_cmpbgt; | 
 |     case Hexagon::A4_cmpbgtui:      return Hexagon::A4_cmpbgtu; | 
 |     case Hexagon::A4_cmpheqi:       return Hexagon::A4_cmpheq; | 
 |     case Hexagon::A4_cmphgti:       return Hexagon::A4_cmphgt; | 
 |     case Hexagon::A4_cmphgtui:      return Hexagon::A4_cmphgtu; | 
 |     case Hexagon::A4_combineii:     return Hexagon::A4_combineir; | 
 |     case Hexagon::A4_combineir:     return TargetOpcode::REG_SEQUENCE; | 
 |     case Hexagon::A4_combineri:     return TargetOpcode::REG_SEQUENCE; | 
 |     case Hexagon::A4_rcmpeqi:       return Hexagon::A4_rcmpeq; | 
 |     case Hexagon::A4_rcmpneqi:      return Hexagon::A4_rcmpneq; | 
 |     case Hexagon::C2_cmoveif:       return Hexagon::A2_tfrpf; | 
 |     case Hexagon::C2_cmoveit:       return Hexagon::A2_tfrpt; | 
 |     case Hexagon::C2_cmpeqi:        return Hexagon::C2_cmpeq; | 
 |     case Hexagon::C2_cmpgti:        return Hexagon::C2_cmpgt; | 
 |     case Hexagon::C2_cmpgtui:       return Hexagon::C2_cmpgtu; | 
 |     case Hexagon::C2_muxii:         return Hexagon::C2_muxir; | 
 |     case Hexagon::C2_muxir:         return Hexagon::C2_mux; | 
 |     case Hexagon::C2_muxri:         return Hexagon::C2_mux; | 
 |     case Hexagon::C4_cmpltei:       return Hexagon::C4_cmplte; | 
 |     case Hexagon::C4_cmplteui:      return Hexagon::C4_cmplteu; | 
 |     case Hexagon::C4_cmpneqi:       return Hexagon::C4_cmpneq; | 
 |     case Hexagon::M2_accii:         return Hexagon::M2_acci;        // T -> T | 
 |     /* No M2_macsin */ | 
 |     case Hexagon::M2_macsip:        return Hexagon::M2_maci;        // T -> T | 
 |     case Hexagon::M2_mpysin:        return Hexagon::M2_mpyi; | 
 |     case Hexagon::M2_mpysip:        return Hexagon::M2_mpyi; | 
 |     case Hexagon::M2_mpysmi:        return Hexagon::M2_mpyi; | 
 |     case Hexagon::M2_naccii:        return Hexagon::M2_nacci;       // T -> T | 
 |     case Hexagon::M4_mpyri_addi:    return Hexagon::M4_mpyri_addr; | 
 |     case Hexagon::M4_mpyri_addr:    return Hexagon::M4_mpyrr_addr;  // _ -> T | 
 |     case Hexagon::M4_mpyrr_addi:    return Hexagon::M4_mpyrr_addr;  // _ -> T | 
 |     case Hexagon::S4_addaddi:       return Hexagon::M2_acci;        // _ -> T | 
 |     case Hexagon::S4_addi_asl_ri:   return Hexagon::S2_asl_i_r_acc; // T -> T | 
 |     case Hexagon::S4_addi_lsr_ri:   return Hexagon::S2_lsr_i_r_acc; // T -> T | 
 |     case Hexagon::S4_andi_asl_ri:   return Hexagon::S2_asl_i_r_and; // T -> T | 
 |     case Hexagon::S4_andi_lsr_ri:   return Hexagon::S2_lsr_i_r_and; // T -> T | 
 |     case Hexagon::S4_ori_asl_ri:    return Hexagon::S2_asl_i_r_or;  // T -> T | 
 |     case Hexagon::S4_ori_lsr_ri:    return Hexagon::S2_lsr_i_r_or;  // T -> T | 
 |     case Hexagon::S4_subaddi:       return Hexagon::M2_subacc;      // _ -> T | 
 |     case Hexagon::S4_subi_asl_ri:   return Hexagon::S2_asl_i_r_nac; // T -> T | 
 |     case Hexagon::S4_subi_lsr_ri:   return Hexagon::S2_lsr_i_r_nac; // T -> T | 
 |  | 
 |     // Store-immediates: | 
 |     case Hexagon::S4_storeirbf_io:  return Hexagon::S2_pstorerbf_io; | 
 |     case Hexagon::S4_storeirb_io:   return Hexagon::S2_storerb_io; | 
 |     case Hexagon::S4_storeirbt_io:  return Hexagon::S2_pstorerbt_io; | 
 |     case Hexagon::S4_storeirhf_io:  return Hexagon::S2_pstorerhf_io; | 
 |     case Hexagon::S4_storeirh_io:   return Hexagon::S2_storerh_io; | 
 |     case Hexagon::S4_storeirht_io:  return Hexagon::S2_pstorerht_io; | 
 |     case Hexagon::S4_storeirif_io:  return Hexagon::S2_pstorerif_io; | 
 |     case Hexagon::S4_storeiri_io:   return Hexagon::S2_storeri_io; | 
 |     case Hexagon::S4_storeirit_io:  return Hexagon::S2_pstorerit_io; | 
 |  | 
 |     default: | 
 |       break; | 
 |   } | 
 |   return 0; | 
 | } | 
 |  | 
 | // Return the allowable deviation from the current value of Rb (i.e. the | 
 | // range of values that can be added to the current value) which the | 
 | // instruction MI can accommodate. | 
 | // The instruction MI is a user of register Rb, which is defined via an | 
 | // extender. It may be possible for MI to be tweaked to work for a register | 
 | // defined with a slightly different value. For example | 
 | //   ... = L2_loadrub_io Rb, 1 | 
 | // can be modifed to be | 
 | //   ... = L2_loadrub_io Rb', 0 | 
 | // if Rb' = Rb+1. | 
 | // The range for Rb would be [Min+1, Max+1], where [Min, Max] is a range | 
 | // for L2_loadrub with offset 0. That means that Rb could be replaced with | 
 | // Rc, where Rc-Rb belongs to [Min+1, Max+1]. | 
 | OffsetRange HCE::getOffsetRange(Register Rb, const MachineInstr &MI) const { | 
 |   unsigned Opc = MI.getOpcode(); | 
 |   // Instructions that are constant-extended may be replaced with something | 
 |   // else that no longer offers the same range as the original. | 
 |   if (!isRegOffOpcode(Opc) || HII->isConstExtended(MI)) | 
 |     return OffsetRange::zero(); | 
 |  | 
 |   if (Opc == Hexagon::A2_addi) { | 
 |     const MachineOperand &Op1 = MI.getOperand(1), &Op2 = MI.getOperand(2); | 
 |     if (Rb != Register(Op1) || !Op2.isImm()) | 
 |       return OffsetRange::zero(); | 
 |     OffsetRange R = { -(1<<15)+1, (1<<15)-1, 1 }; | 
 |     return R.shift(Op2.getImm()); | 
 |   } | 
 |  | 
 |   // HII::getBaseAndOffsetPosition returns the increment position as "offset". | 
 |   if (HII->isPostIncrement(MI)) | 
 |     return OffsetRange::zero(); | 
 |  | 
 |   const MCInstrDesc &D = HII->get(Opc); | 
 |   assert(D.mayLoad() || D.mayStore()); | 
 |  | 
 |   unsigned BaseP, OffP; | 
 |   if (!HII->getBaseAndOffsetPosition(MI, BaseP, OffP) || | 
 |       Rb != Register(MI.getOperand(BaseP)) || | 
 |       !MI.getOperand(OffP).isImm()) | 
 |     return OffsetRange::zero(); | 
 |  | 
 |   uint64_t F = (D.TSFlags >> HexagonII::MemAccessSizePos) & | 
 |                   HexagonII::MemAccesSizeMask; | 
 |   uint8_t A = HexagonII::getMemAccessSizeInBytes(HexagonII::MemAccessSize(F)); | 
 |   unsigned L = Log2_32(A); | 
 |   unsigned S = 10+L;  // sint11_L | 
 |   int32_t Min = -alignDown((1<<S)-1, A); | 
 |  | 
 |   // The range will be shifted by Off. To prefer non-negative offsets, | 
 |   // adjust Max accordingly. | 
 |   int32_t Off = MI.getOperand(OffP).getImm(); | 
 |   int32_t Max = Off >= 0 ? 0 : -Off; | 
 |  | 
 |   OffsetRange R = { Min, Max, A }; | 
 |   return R.shift(Off); | 
 | } | 
 |  | 
 | // Return the allowable deviation from the current value of the extender ED, | 
 | // for which the instruction corresponding to ED can be modified without | 
 | // using an extender. | 
 | // The instruction uses the extender directly. It will be replaced with | 
 | // another instruction, say MJ, where the extender will be replaced with a | 
 | // register. MJ can allow some variability with respect to the value of | 
 | // that register, as is the case with indexed memory instructions. | 
 | OffsetRange HCE::getOffsetRange(const ExtDesc &ED) const { | 
 |   // The only way that there can be a non-zero range available is if | 
 |   // the instruction using ED will be converted to an indexed memory | 
 |   // instruction. | 
 |   unsigned IdxOpc = getRegOffOpcode(ED.UseMI->getOpcode()); | 
 |   switch (IdxOpc) { | 
 |     case 0: | 
 |       return OffsetRange::zero(); | 
 |     case Hexagon::A2_addi:    // s16 | 
 |       return { -32767, 32767, 1 }; | 
 |     case Hexagon::A2_subri:   // s10 | 
 |       return { -511, 511, 1 }; | 
 |   } | 
 |  | 
 |   if (!ED.UseMI->mayLoad() && !ED.UseMI->mayStore()) | 
 |     return OffsetRange::zero(); | 
 |   const MCInstrDesc &D = HII->get(IdxOpc); | 
 |   uint64_t F = (D.TSFlags >> HexagonII::MemAccessSizePos) & | 
 |                   HexagonII::MemAccesSizeMask; | 
 |   uint8_t A = HexagonII::getMemAccessSizeInBytes(HexagonII::MemAccessSize(F)); | 
 |   unsigned L = Log2_32(A); | 
 |   unsigned S = 10+L;  // sint11_L | 
 |   int32_t Min = -alignDown((1<<S)-1, A); | 
 |   int32_t Max = 0;  // Force non-negative offsets. | 
 |   return { Min, Max, A }; | 
 | } | 
 |  | 
 | // Get the allowable deviation from the current value of Rd by checking | 
 | // all uses of Rd. | 
 | OffsetRange HCE::getOffsetRange(Register Rd) const { | 
 |   OffsetRange Range; | 
 |   for (const MachineOperand &Op : MRI->use_operands(Rd.Reg)) { | 
 |     // Make sure that the register being used by this operand is identical | 
 |     // to the register that was defined: using a different subregister | 
 |     // precludes any non-trivial range. | 
 |     if (Rd != Register(Op)) | 
 |       return OffsetRange::zero(); | 
 |     Range.intersect(getOffsetRange(Rd, *Op.getParent())); | 
 |   } | 
 |   return Range; | 
 | } | 
 |  | 
 | void HCE::recordExtender(MachineInstr &MI, unsigned OpNum) { | 
 |   unsigned Opc = MI.getOpcode(); | 
 |   ExtDesc ED; | 
 |   ED.OpNum = OpNum; | 
 |  | 
 |   bool IsLoad = MI.mayLoad(); | 
 |   bool IsStore = MI.mayStore(); | 
 |  | 
 |   // Fixed stack slots have negative indexes, and they cannot be used | 
 |   // with TRI::stackSlot2Index and TRI::index2StackSlot. This is somewhat | 
 |   // unfortunate, but should not be a frequent thing. | 
 |   for (MachineOperand &Op : MI.operands()) | 
 |     if (Op.isFI() && Op.getIndex() < 0) | 
 |       return; | 
 |  | 
 |   if (IsLoad || IsStore) { | 
 |     unsigned AM = HII->getAddrMode(MI); | 
 |     switch (AM) { | 
 |       // (Re: ##Off + Rb<<S) = Rd: ##Val | 
 |       case HexagonII::Absolute:       // (__: ## + __<<_) | 
 |         break; | 
 |       case HexagonII::AbsoluteSet:    // (Rd: ## + __<<_) | 
 |         ED.Rd = MI.getOperand(OpNum-1); | 
 |         ED.IsDef = true; | 
 |         break; | 
 |       case HexagonII::BaseImmOffset:  // (__: ## + Rs<<0) | 
 |         // Store-immediates are treated as non-memory operations, since | 
 |         // it's the value being stored that is extended (as opposed to | 
 |         // a part of the address). | 
 |         if (!isStoreImmediate(Opc)) | 
 |           ED.Expr.Rs = MI.getOperand(OpNum-1); | 
 |         break; | 
 |       case HexagonII::BaseLongOffset: // (__: ## + Rs<<S) | 
 |         ED.Expr.Rs = MI.getOperand(OpNum-2); | 
 |         ED.Expr.S = MI.getOperand(OpNum-1).getImm(); | 
 |         break; | 
 |       default: | 
 |         llvm_unreachable("Unhandled memory instruction"); | 
 |     } | 
 |   } else { | 
 |     switch (Opc) { | 
 |       case Hexagon::A2_tfrsi:         // (Rd: ## + __<<_) | 
 |         ED.Rd = MI.getOperand(0); | 
 |         ED.IsDef = true; | 
 |         break; | 
 |       case Hexagon::A2_combineii:     // (Rd: ## + __<<_) | 
 |       case Hexagon::A4_combineir: | 
 |         ED.Rd = { MI.getOperand(0).getReg(), Hexagon::isub_hi }; | 
 |         ED.IsDef = true; | 
 |         break; | 
 |       case Hexagon::A4_combineri:     // (Rd: ## + __<<_) | 
 |         ED.Rd = { MI.getOperand(0).getReg(), Hexagon::isub_lo }; | 
 |         ED.IsDef = true; | 
 |         break; | 
 |       case Hexagon::A2_addi:          // (Rd: ## + Rs<<0) | 
 |         ED.Rd = MI.getOperand(0); | 
 |         ED.Expr.Rs = MI.getOperand(OpNum-1); | 
 |         break; | 
 |       case Hexagon::M2_accii:         // (__: ## + Rs<<0) | 
 |       case Hexagon::M2_naccii: | 
 |       case Hexagon::S4_addaddi: | 
 |         ED.Expr.Rs = MI.getOperand(OpNum-1); | 
 |         break; | 
 |       case Hexagon::A2_subri:         // (Rd: ## - Rs<<0) | 
 |         ED.Rd = MI.getOperand(0); | 
 |         ED.Expr.Rs = MI.getOperand(OpNum+1); | 
 |         ED.Expr.Neg = true; | 
 |         break; | 
 |       case Hexagon::S4_subaddi:       // (__: ## - Rs<<0) | 
 |         ED.Expr.Rs = MI.getOperand(OpNum+1); | 
 |         ED.Expr.Neg = true; | 
 |         break; | 
 |       default:                        // (__: ## + __<<_) | 
 |         break; | 
 |     } | 
 |   } | 
 |  | 
 |   ED.UseMI = &MI; | 
 |  | 
 |   // Ignore unnamed globals. | 
 |   ExtRoot ER(ED.getOp()); | 
 |   if (ER.Kind == MachineOperand::MO_GlobalAddress) | 
 |     if (ER.V.GV->getName().empty()) | 
 |       return; | 
 |   Extenders.push_back(ED); | 
 | } | 
 |  | 
 | void HCE::collectInstr(MachineInstr &MI) { | 
 |   if (!HII->isConstExtended(MI)) | 
 |     return; | 
 |  | 
 |   // Skip some non-convertible instructions. | 
 |   unsigned Opc = MI.getOpcode(); | 
 |   switch (Opc) { | 
 |     case Hexagon::M2_macsin:  // There is no Rx -= mpyi(Rs,Rt). | 
 |     case Hexagon::C4_addipc: | 
 |     case Hexagon::S4_or_andi: | 
 |     case Hexagon::S4_or_andix: | 
 |     case Hexagon::S4_or_ori: | 
 |       return; | 
 |   } | 
 |   recordExtender(MI, HII->getCExtOpNum(MI)); | 
 | } | 
 |  | 
 | void HCE::collect(MachineFunction &MF) { | 
 |   Extenders.clear(); | 
 |   for (MachineBasicBlock &MBB : MF) { | 
 |     // Skip unreachable blocks. | 
 |     if (MBB.getNumber() == -1) | 
 |       continue; | 
 |     for (MachineInstr &MI : MBB) | 
 |       collectInstr(MI); | 
 |   } | 
 | } | 
 |  | 
 | void HCE::assignInits(const ExtRoot &ER, unsigned Begin, unsigned End, | 
 |       AssignmentMap &IMap) { | 
 |   // Basic correctness: make sure that all extenders in the range [Begin..End) | 
 |   // share the same root ER. | 
 |   for (unsigned I = Begin; I != End; ++I) | 
 |     assert(ER == ExtRoot(Extenders[I].getOp())); | 
 |  | 
 |   // Construct the list of ranges, such that for each P in Ranges[I], | 
 |   // a register Reg = ER+P can be used in place of Extender[I]. If the | 
 |   // instruction allows, uses in the form of Reg+Off are considered | 
 |   // (here, Off = required_value - P). | 
 |   std::vector<OffsetRange> Ranges(End-Begin); | 
 |  | 
 |   // For each extender that is a def, visit all uses of the defined register, | 
 |   // and produce an offset range that works for all uses. The def doesn't | 
 |   // have to be checked, because it can become dead if all uses can be updated | 
 |   // to use a different reg/offset. | 
 |   for (unsigned I = Begin; I != End; ++I) { | 
 |     const ExtDesc &ED = Extenders[I]; | 
 |     if (!ED.IsDef) | 
 |       continue; | 
 |     ExtValue EV(ED); | 
 |     LLVM_DEBUG(dbgs() << " =" << I << ". " << EV << "  " << ED << '\n'); | 
 |     assert(ED.Rd.Reg != 0); | 
 |     Ranges[I-Begin] = getOffsetRange(ED.Rd).shift(EV.Offset); | 
 |     // A2_tfrsi is a special case: it will be replaced with A2_addi, which | 
 |     // has a 16-bit signed offset. This means that A2_tfrsi not only has a | 
 |     // range coming from its uses, but also from the fact that its replacement | 
 |     // has a range as well. | 
 |     if (ED.UseMI->getOpcode() == Hexagon::A2_tfrsi) { | 
 |       int32_t D = alignDown(32767, Ranges[I-Begin].Align); // XXX hardcoded | 
 |       Ranges[I-Begin].extendBy(-D).extendBy(D); | 
 |     } | 
 |   } | 
 |  | 
 |   // Visit all non-def extenders. For each one, determine the offset range | 
 |   // available for it. | 
 |   for (unsigned I = Begin; I != End; ++I) { | 
 |     const ExtDesc &ED = Extenders[I]; | 
 |     if (ED.IsDef) | 
 |       continue; | 
 |     ExtValue EV(ED); | 
 |     LLVM_DEBUG(dbgs() << "  " << I << ". " << EV << "  " << ED << '\n'); | 
 |     OffsetRange Dev = getOffsetRange(ED); | 
 |     Ranges[I-Begin].intersect(Dev.shift(EV.Offset)); | 
 |   } | 
 |  | 
 |   // Here for each I there is a corresponding Range[I]. Construct the | 
 |   // inverse map, that to each range will assign the set of indexes in | 
 |   // [Begin..End) that this range corresponds to. | 
 |   std::map<OffsetRange, IndexList> RangeMap; | 
 |   for (unsigned I = Begin; I != End; ++I) | 
 |     RangeMap[Ranges[I-Begin]].insert(I); | 
 |  | 
 |   LLVM_DEBUG({ | 
 |     dbgs() << "Ranges\n"; | 
 |     for (unsigned I = Begin; I != End; ++I) | 
 |       dbgs() << "  " << I << ". " << Ranges[I-Begin] << '\n'; | 
 |     dbgs() << "RangeMap\n"; | 
 |     for (auto &P : RangeMap) { | 
 |       dbgs() << "  " << P.first << " ->"; | 
 |       for (unsigned I : P.second) | 
 |         dbgs() << ' ' << I; | 
 |       dbgs() << '\n'; | 
 |     } | 
 |   }); | 
 |  | 
 |   // Select the definition points, and generate the assignment between | 
 |   // these points and the uses. | 
 |  | 
 |   // For each candidate offset, keep a pair CandData consisting of | 
 |   // the total number of ranges containing that candidate, and the | 
 |   // vector of corresponding RangeTree nodes. | 
 |   using CandData = std::pair<unsigned, SmallVector<RangeTree::Node*,8>>; | 
 |   std::map<int32_t, CandData> CandMap; | 
 |  | 
 |   RangeTree Tree; | 
 |   for (const OffsetRange &R : Ranges) | 
 |     Tree.add(R); | 
 |   SmallVector<RangeTree::Node*,8> Nodes; | 
 |   Tree.order(Nodes); | 
 |  | 
 |   auto MaxAlign = [](const SmallVectorImpl<RangeTree::Node*> &Nodes, | 
 |                      uint8_t Align, uint8_t Offset) { | 
 |     for (RangeTree::Node *N : Nodes) { | 
 |       if (N->Range.Align <= Align || N->Range.Offset < Offset) | 
 |         continue; | 
 |       if ((N->Range.Offset - Offset) % Align != 0) | 
 |         continue; | 
 |       Align = N->Range.Align; | 
 |       Offset = N->Range.Offset; | 
 |     } | 
 |     return std::make_pair(Align, Offset); | 
 |   }; | 
 |  | 
 |   // Construct the set of all potential definition points from the endpoints | 
 |   // of the ranges. If a given endpoint also belongs to a different range, | 
 |   // but with a higher alignment, also consider the more-highly-aligned | 
 |   // value of this endpoint. | 
 |   std::set<int32_t> CandSet; | 
 |   for (RangeTree::Node *N : Nodes) { | 
 |     const OffsetRange &R = N->Range; | 
 |     auto P0 = MaxAlign(Tree.nodesWith(R.Min, false), R.Align, R.Offset); | 
 |     CandSet.insert(R.Min); | 
 |     if (R.Align < P0.first) | 
 |       CandSet.insert(adjustUp(R.Min, P0.first, P0.second)); | 
 |     auto P1 = MaxAlign(Tree.nodesWith(R.Max, false), R.Align, R.Offset); | 
 |     CandSet.insert(R.Max); | 
 |     if (R.Align < P1.first) | 
 |       CandSet.insert(adjustDown(R.Max, P1.first, P1.second)); | 
 |   } | 
 |  | 
 |   // Build the assignment map: candidate C -> { list of extender indexes }. | 
 |   // This has to be done iteratively: | 
 |   // - pick the candidate that covers the maximum number of extenders, | 
 |   // - add the candidate to the map, | 
 |   // - remove the extenders from the pool. | 
 |   while (true) { | 
 |     using CMap = std::map<int32_t,unsigned>; | 
 |     CMap Counts; | 
 |     for (auto It = CandSet.begin(), Et = CandSet.end(); It != Et; ) { | 
 |       auto &&V = Tree.nodesWith(*It); | 
 |       unsigned N = std::accumulate(V.begin(), V.end(), 0u, | 
 |                     [](unsigned Acc, const RangeTree::Node *N) { | 
 |                       return Acc + N->Count; | 
 |                     }); | 
 |       if (N != 0) | 
 |         Counts.insert({*It, N}); | 
 |       It = (N != 0) ? std::next(It) : CandSet.erase(It); | 
 |     } | 
 |     if (Counts.empty()) | 
 |       break; | 
 |  | 
 |     // Find the best candidate with respect to the number of extenders covered. | 
 |     auto BestIt = std::max_element(Counts.begin(), Counts.end(), | 
 |                     [](const CMap::value_type &A, const CMap::value_type &B) { | 
 |                       return A.second < B.second || | 
 |                              (A.second == B.second && A < B); | 
 |                     }); | 
 |     int32_t Best = BestIt->first; | 
 |     ExtValue BestV(ER, Best); | 
 |     for (RangeTree::Node *N : Tree.nodesWith(Best)) { | 
 |       for (unsigned I : RangeMap[N->Range]) | 
 |         IMap[{BestV,Extenders[I].Expr}].insert(I); | 
 |       Tree.erase(N); | 
 |     } | 
 |   } | 
 |  | 
 |   LLVM_DEBUG(dbgs() << "IMap (before fixup) = " << PrintIMap(IMap, *HRI)); | 
 |  | 
 |   // There is some ambiguity in what initializer should be used, if the | 
 |   // descriptor's subexpression is non-trivial: it can be the entire | 
 |   // subexpression (which is what has been done so far), or it can be | 
 |   // the extender's value itself, if all corresponding extenders have the | 
 |   // exact value of the initializer (i.e. require offset of 0). | 
 |  | 
 |   // To reduce the number of initializers, merge such special cases. | 
 |   for (std::pair<const ExtenderInit,IndexList> &P : IMap) { | 
 |     // Skip trivial initializers. | 
 |     if (P.first.second.trivial()) | 
 |       continue; | 
 |     // If the corresponding trivial initializer does not exist, skip this | 
 |     // entry. | 
 |     const ExtValue &EV = P.first.first; | 
 |     AssignmentMap::iterator F = IMap.find({EV, ExtExpr()}); | 
 |     if (F == IMap.end()) | 
 |       continue; | 
 |  | 
 |     // Finally, check if all extenders have the same value as the initializer. | 
 |     // Make sure that extenders that are a part of a stack address are not | 
 |     // merged with those that aren't. Stack addresses need an offset field | 
 |     // (to be used by frame index elimination), while non-stack expressions | 
 |     // can be replaced with forms (such as rr) that do not have such a field. | 
 |     // Example: | 
 |     // | 
 |     // Collected 3 extenders | 
 |     //  =2. imm:0  off:32968  bb#2: %7 = ## + __ << 0, def | 
 |     //   0. imm:0  off:267  bb#0: __ = ## + SS#1 << 0 | 
 |     //   1. imm:0  off:267  bb#1: __ = ## + SS#1 << 0 | 
 |     // Ranges | 
 |     //   0. [-756,267]a1+0 | 
 |     //   1. [-756,267]a1+0 | 
 |     //   2. [201,65735]a1+0 | 
 |     // RangeMap | 
 |     //   [-756,267]a1+0 -> 0 1 | 
 |     //   [201,65735]a1+0 -> 2 | 
 |     // IMap (before fixup) = { | 
 |     //   [imm:0  off:267, ## + __ << 0] -> { 2 } | 
 |     //   [imm:0  off:267, ## + SS#1 << 0] -> { 0 1 } | 
 |     // } | 
 |     // IMap (after fixup) = { | 
 |     //   [imm:0  off:267, ## + __ << 0] -> { 2 0 1 } | 
 |     //   [imm:0  off:267, ## + SS#1 << 0] -> { } | 
 |     // } | 
 |     // Inserted def in bb#0 for initializer: [imm:0  off:267, ## + __ << 0] | 
 |     //   %12:intregs = A2_tfrsi 267 | 
 |     // | 
 |     // The result was | 
 |     //   %12:intregs = A2_tfrsi 267 | 
 |     //   S4_pstorerbt_rr %3, %12, %stack.1, 0, killed %4 | 
 |     // Which became | 
 |     //   r0 = #267 | 
 |     //   if (p0.new) memb(r0+r29<<#4) = r2 | 
 |  | 
 |     bool IsStack = any_of(F->second, [this](unsigned I) { | 
 |                       return Extenders[I].Expr.Rs.isSlot(); | 
 |                    }); | 
 |     auto SameValue = [&EV,this,IsStack](unsigned I) { | 
 |       const ExtDesc &ED = Extenders[I]; | 
 |       return ED.Expr.Rs.isSlot() == IsStack && | 
 |              ExtValue(ED).Offset == EV.Offset; | 
 |     }; | 
 |     if (all_of(P.second, SameValue)) { | 
 |       F->second.insert(P.second.begin(), P.second.end()); | 
 |       P.second.clear(); | 
 |     } | 
 |   } | 
 |  | 
 |   LLVM_DEBUG(dbgs() << "IMap (after fixup) = " << PrintIMap(IMap, *HRI)); | 
 | } | 
 |  | 
 | void HCE::calculatePlacement(const ExtenderInit &ExtI, const IndexList &Refs, | 
 |       LocDefList &Defs) { | 
 |   if (Refs.empty()) | 
 |     return; | 
 |  | 
 |   // The placement calculation is somewhat simple right now: it finds a | 
 |   // single location for the def that dominates all refs. Since this may | 
 |   // place the def far from the uses, producing several locations for | 
 |   // defs that collectively dominate all refs could be better. | 
 |   // For now only do the single one. | 
 |   DenseSet<MachineBasicBlock*> Blocks; | 
 |   DenseSet<MachineInstr*> RefMIs; | 
 |   const ExtDesc &ED0 = Extenders[Refs[0]]; | 
 |   MachineBasicBlock *DomB = ED0.UseMI->getParent(); | 
 |   RefMIs.insert(ED0.UseMI); | 
 |   Blocks.insert(DomB); | 
 |   for (unsigned i = 1, e = Refs.size(); i != e; ++i) { | 
 |     const ExtDesc &ED = Extenders[Refs[i]]; | 
 |     MachineBasicBlock *MBB = ED.UseMI->getParent(); | 
 |     RefMIs.insert(ED.UseMI); | 
 |     DomB = MDT->findNearestCommonDominator(DomB, MBB); | 
 |     Blocks.insert(MBB); | 
 |   } | 
 |  | 
 | #ifndef NDEBUG | 
 |   // The block DomB should be dominated by the def of each register used | 
 |   // in the initializer. | 
 |   Register Rs = ExtI.second.Rs;  // Only one reg allowed now. | 
 |   const MachineInstr *DefI = Rs.isVReg() ? MRI->getVRegDef(Rs.Reg) : nullptr; | 
 |  | 
 |   // This should be guaranteed given that the entire expression is used | 
 |   // at each instruction in Refs. Add an assertion just in case. | 
 |   assert(!DefI || MDT->dominates(DefI->getParent(), DomB)); | 
 | #endif | 
 |  | 
 |   MachineBasicBlock::iterator It; | 
 |   if (Blocks.count(DomB)) { | 
 |     // Try to find the latest possible location for the def. | 
 |     MachineBasicBlock::iterator End = DomB->end(); | 
 |     for (It = DomB->begin(); It != End; ++It) | 
 |       if (RefMIs.count(&*It)) | 
 |         break; | 
 |     assert(It != End && "Should have found a ref in DomB"); | 
 |   } else { | 
 |     // DomB does not contain any refs. | 
 |     It = DomB->getFirstTerminator(); | 
 |   } | 
 |   Loc DefLoc(DomB, It); | 
 |   Defs.emplace_back(DefLoc, Refs); | 
 | } | 
 |  | 
 | HCE::Register HCE::insertInitializer(Loc DefL, const ExtenderInit &ExtI) { | 
 |   llvm::Register DefR = MRI->createVirtualRegister(&Hexagon::IntRegsRegClass); | 
 |   MachineBasicBlock &MBB = *DefL.Block; | 
 |   MachineBasicBlock::iterator At = DefL.At; | 
 |   DebugLoc dl = DefL.Block->findDebugLoc(DefL.At); | 
 |   const ExtValue &EV = ExtI.first; | 
 |   MachineOperand ExtOp(EV); | 
 |  | 
 |   const ExtExpr &Ex = ExtI.second; | 
 |   const MachineInstr *InitI = nullptr; | 
 |  | 
 |   if (Ex.Rs.isSlot()) { | 
 |     assert(Ex.S == 0 && "Cannot have a shift of a stack slot"); | 
 |     assert(!Ex.Neg && "Cannot subtract a stack slot"); | 
 |     // DefR = PS_fi Rb,##EV | 
 |     InitI = BuildMI(MBB, At, dl, HII->get(Hexagon::PS_fi), DefR) | 
 |               .add(MachineOperand(Ex.Rs)) | 
 |               .add(ExtOp); | 
 |   } else { | 
 |     assert((Ex.Rs.Reg == 0 || Ex.Rs.isVReg()) && "Expecting virtual register"); | 
 |     if (Ex.trivial()) { | 
 |       // DefR = ##EV | 
 |       InitI = BuildMI(MBB, At, dl, HII->get(Hexagon::A2_tfrsi), DefR) | 
 |                 .add(ExtOp); | 
 |     } else if (Ex.S == 0) { | 
 |       if (Ex.Neg) { | 
 |         // DefR = sub(##EV,Rb) | 
 |         InitI = BuildMI(MBB, At, dl, HII->get(Hexagon::A2_subri), DefR) | 
 |                   .add(ExtOp) | 
 |                   .add(MachineOperand(Ex.Rs)); | 
 |       } else { | 
 |         // DefR = add(Rb,##EV) | 
 |         InitI = BuildMI(MBB, At, dl, HII->get(Hexagon::A2_addi), DefR) | 
 |                   .add(MachineOperand(Ex.Rs)) | 
 |                   .add(ExtOp); | 
 |       } | 
 |     } else { | 
 |       if (HST->useCompound()) { | 
 |         unsigned NewOpc = Ex.Neg ? Hexagon::S4_subi_asl_ri | 
 |                                  : Hexagon::S4_addi_asl_ri; | 
 |         // DefR = add(##EV,asl(Rb,S)) | 
 |         InitI = BuildMI(MBB, At, dl, HII->get(NewOpc), DefR) | 
 |                   .add(ExtOp) | 
 |                   .add(MachineOperand(Ex.Rs)) | 
 |                   .addImm(Ex.S); | 
 |       } else { | 
 |         // No compounds are available. It is not clear whether we should | 
 |         // even process such extenders where the initializer cannot be | 
 |         // a single instruction, but do it for now. | 
 |         llvm::Register TmpR = MRI->createVirtualRegister(&Hexagon::IntRegsRegClass); | 
 |         BuildMI(MBB, At, dl, HII->get(Hexagon::S2_asl_i_r), TmpR) | 
 |           .add(MachineOperand(Ex.Rs)) | 
 |           .addImm(Ex.S); | 
 |         if (Ex.Neg) | 
 |           InitI = BuildMI(MBB, At, dl, HII->get(Hexagon::A2_subri), DefR) | 
 |                     .add(ExtOp) | 
 |                     .add(MachineOperand(Register(TmpR, 0))); | 
 |         else | 
 |           InitI = BuildMI(MBB, At, dl, HII->get(Hexagon::A2_addi), DefR) | 
 |                     .add(MachineOperand(Register(TmpR, 0))) | 
 |                     .add(ExtOp); | 
 |       } | 
 |     } | 
 |   } | 
 |  | 
 |   assert(InitI); | 
 |   (void)InitI; | 
 |   LLVM_DEBUG(dbgs() << "Inserted def in bb#" << MBB.getNumber() | 
 |                     << " for initializer: " << PrintInit(ExtI, *HRI) << "\n  " | 
 |                     << *InitI); | 
 |   return { DefR, 0 }; | 
 | } | 
 |  | 
 | // Replace the extender at index Idx with the register ExtR. | 
 | bool HCE::replaceInstrExact(const ExtDesc &ED, Register ExtR) { | 
 |   MachineInstr &MI = *ED.UseMI; | 
 |   MachineBasicBlock &MBB = *MI.getParent(); | 
 |   MachineBasicBlock::iterator At = MI.getIterator(); | 
 |   DebugLoc dl = MI.getDebugLoc(); | 
 |   unsigned ExtOpc = MI.getOpcode(); | 
 |  | 
 |   // With a few exceptions, direct replacement amounts to creating an | 
 |   // instruction with a corresponding register opcode, with all operands | 
 |   // the same, except for the register used in place of the extender. | 
 |   unsigned RegOpc = getDirectRegReplacement(ExtOpc); | 
 |  | 
 |   if (RegOpc == TargetOpcode::REG_SEQUENCE) { | 
 |     if (ExtOpc == Hexagon::A4_combineri) | 
 |       BuildMI(MBB, At, dl, HII->get(RegOpc)) | 
 |         .add(MI.getOperand(0)) | 
 |         .add(MI.getOperand(1)) | 
 |         .addImm(Hexagon::isub_hi) | 
 |         .add(MachineOperand(ExtR)) | 
 |         .addImm(Hexagon::isub_lo); | 
 |     else if (ExtOpc == Hexagon::A4_combineir) | 
 |       BuildMI(MBB, At, dl, HII->get(RegOpc)) | 
 |         .add(MI.getOperand(0)) | 
 |         .add(MachineOperand(ExtR)) | 
 |         .addImm(Hexagon::isub_hi) | 
 |         .add(MI.getOperand(2)) | 
 |         .addImm(Hexagon::isub_lo); | 
 |     else | 
 |       llvm_unreachable("Unexpected opcode became REG_SEQUENCE"); | 
 |     MBB.erase(MI); | 
 |     return true; | 
 |   } | 
 |   if (ExtOpc == Hexagon::C2_cmpgei || ExtOpc == Hexagon::C2_cmpgeui) { | 
 |     unsigned NewOpc = ExtOpc == Hexagon::C2_cmpgei ? Hexagon::C2_cmplt | 
 |                                                    : Hexagon::C2_cmpltu; | 
 |     BuildMI(MBB, At, dl, HII->get(NewOpc)) | 
 |       .add(MI.getOperand(0)) | 
 |       .add(MachineOperand(ExtR)) | 
 |       .add(MI.getOperand(1)); | 
 |     MBB.erase(MI); | 
 |     return true; | 
 |   } | 
 |  | 
 |   if (RegOpc != 0) { | 
 |     MachineInstrBuilder MIB = BuildMI(MBB, At, dl, HII->get(RegOpc)); | 
 |     unsigned RegN = ED.OpNum; | 
 |     // Copy all operands except the one that has the extender. | 
 |     for (unsigned i = 0, e = MI.getNumOperands(); i != e; ++i) { | 
 |       if (i != RegN) | 
 |         MIB.add(MI.getOperand(i)); | 
 |       else | 
 |         MIB.add(MachineOperand(ExtR)); | 
 |     } | 
 |     MIB.cloneMemRefs(MI); | 
 |     MBB.erase(MI); | 
 |     return true; | 
 |   } | 
 |  | 
 |   if (MI.mayLoadOrStore() && !isStoreImmediate(ExtOpc)) { | 
 |     // For memory instructions, there is an asymmetry in the addressing | 
 |     // modes. Addressing modes allowing extenders can be replaced with | 
 |     // addressing modes that use registers, but the order of operands | 
 |     // (or even their number) may be different. | 
 |     // Replacements: | 
 |     //   BaseImmOffset (io)  -> BaseRegOffset (rr) | 
 |     //   BaseLongOffset (ur) -> BaseRegOffset (rr) | 
 |     unsigned RegOpc, Shift; | 
 |     unsigned AM = HII->getAddrMode(MI); | 
 |     if (AM == HexagonII::BaseImmOffset) { | 
 |       RegOpc = HII->changeAddrMode_io_rr(ExtOpc); | 
 |       Shift = 0; | 
 |     } else if (AM == HexagonII::BaseLongOffset) { | 
 |       // Loads:  Rd = L4_loadri_ur Rs, S, ## | 
 |       // Stores: S4_storeri_ur Rs, S, ##, Rt | 
 |       RegOpc = HII->changeAddrMode_ur_rr(ExtOpc); | 
 |       Shift = MI.getOperand(MI.mayLoad() ? 2 : 1).getImm(); | 
 |     } else { | 
 |       llvm_unreachable("Unexpected addressing mode"); | 
 |     } | 
 | #ifndef NDEBUG | 
 |     if (RegOpc == -1u) { | 
 |       dbgs() << "\nExtOpc: " << HII->getName(ExtOpc) << " has no rr version\n"; | 
 |       llvm_unreachable("No corresponding rr instruction"); | 
 |     } | 
 | #endif | 
 |  | 
 |     unsigned BaseP, OffP; | 
 |     HII->getBaseAndOffsetPosition(MI, BaseP, OffP); | 
 |  | 
 |     // Build an rr instruction: (RegOff + RegBase<<0) | 
 |     MachineInstrBuilder MIB = BuildMI(MBB, At, dl, HII->get(RegOpc)); | 
 |     // First, add the def for loads. | 
 |     if (MI.mayLoad()) | 
 |       MIB.add(getLoadResultOp(MI)); | 
 |     // Handle possible predication. | 
 |     if (HII->isPredicated(MI)) | 
 |       MIB.add(getPredicateOp(MI)); | 
 |     // Build the address. | 
 |     MIB.add(MachineOperand(ExtR));      // RegOff | 
 |     MIB.add(MI.getOperand(BaseP));      // RegBase | 
 |     MIB.addImm(Shift);                  // << Shift | 
 |     // Add the stored value for stores. | 
 |     if (MI.mayStore()) | 
 |       MIB.add(getStoredValueOp(MI)); | 
 |     MIB.cloneMemRefs(MI); | 
 |     MBB.erase(MI); | 
 |     return true; | 
 |   } | 
 |  | 
 | #ifndef NDEBUG | 
 |   dbgs() << '\n' << MI; | 
 | #endif | 
 |   llvm_unreachable("Unhandled exact replacement"); | 
 |   return false; | 
 | } | 
 |  | 
 | // Replace the extender ED with a form corresponding to the initializer ExtI. | 
 | bool HCE::replaceInstrExpr(const ExtDesc &ED, const ExtenderInit &ExtI, | 
 |       Register ExtR, int32_t &Diff) { | 
 |   MachineInstr &MI = *ED.UseMI; | 
 |   MachineBasicBlock &MBB = *MI.getParent(); | 
 |   MachineBasicBlock::iterator At = MI.getIterator(); | 
 |   DebugLoc dl = MI.getDebugLoc(); | 
 |   unsigned ExtOpc = MI.getOpcode(); | 
 |  | 
 |   if (ExtOpc == Hexagon::A2_tfrsi) { | 
 |     // A2_tfrsi is a special case: it's replaced with A2_addi, which introduces | 
 |     // another range. One range is the one that's common to all tfrsi's uses, | 
 |     // this one is the range of immediates in A2_addi. When calculating ranges, | 
 |     // the addi's 16-bit argument was included, so now we need to make it such | 
 |     // that the produced value is in the range for the uses alone. | 
 |     // Most of the time, simply adding Diff will make the addi produce exact | 
 |     // result, but if Diff is outside of the 16-bit range, some adjustment | 
 |     // will be needed. | 
 |     unsigned IdxOpc = getRegOffOpcode(ExtOpc); | 
 |     assert(IdxOpc == Hexagon::A2_addi); | 
 |  | 
 |     // Clamp Diff to the 16 bit range. | 
 |     int32_t D = isInt<16>(Diff) ? Diff : (Diff > 0 ? 32767 : -32768); | 
 |     if (Diff > 32767) { | 
 |       // Split Diff into two values: one that is close to min/max int16, | 
 |       // and the other being the rest, and such that both have the same | 
 |       // "alignment" as Diff. | 
 |       uint32_t UD = Diff; | 
 |       OffsetRange R = getOffsetRange(MI.getOperand(0)); | 
 |       uint32_t A = std::min<uint32_t>(R.Align, 1u << llvm::countr_zero(UD)); | 
 |       D &= ~(A-1); | 
 |     } | 
 |     BuildMI(MBB, At, dl, HII->get(IdxOpc)) | 
 |       .add(MI.getOperand(0)) | 
 |       .add(MachineOperand(ExtR)) | 
 |       .addImm(D); | 
 |     Diff -= D; | 
 | #ifndef NDEBUG | 
 |     // Make sure the output is within allowable range for uses. | 
 |     // "Diff" is a difference in the "opposite direction", i.e. Ext - DefV, | 
 |     // not DefV - Ext, as the getOffsetRange would calculate. | 
 |     OffsetRange Uses = getOffsetRange(MI.getOperand(0)); | 
 |     if (!Uses.contains(-Diff)) | 
 |       dbgs() << "Diff: " << -Diff << " out of range " << Uses | 
 |              << " for " << MI; | 
 |     assert(Uses.contains(-Diff)); | 
 | #endif | 
 |     MBB.erase(MI); | 
 |     return true; | 
 |   } | 
 |  | 
 |   const ExtValue &EV = ExtI.first; (void)EV; | 
 |   const ExtExpr &Ex = ExtI.second; (void)Ex; | 
 |  | 
 |   if (ExtOpc == Hexagon::A2_addi || ExtOpc == Hexagon::A2_subri) { | 
 |     // If addi/subri are replaced with the exactly matching initializer, | 
 |     // they amount to COPY. | 
 |     // Check that the initializer is an exact match (for simplicity). | 
 | #ifndef NDEBUG | 
 |     bool IsAddi = ExtOpc == Hexagon::A2_addi; | 
 |     const MachineOperand &RegOp = MI.getOperand(IsAddi ? 1 : 2); | 
 |     const MachineOperand &ImmOp = MI.getOperand(IsAddi ? 2 : 1); | 
 |     assert(Ex.Rs == RegOp && EV == ImmOp && Ex.Neg != IsAddi && | 
 |            "Initializer mismatch"); | 
 | #endif | 
 |     BuildMI(MBB, At, dl, HII->get(TargetOpcode::COPY)) | 
 |       .add(MI.getOperand(0)) | 
 |       .add(MachineOperand(ExtR)); | 
 |     Diff = 0; | 
 |     MBB.erase(MI); | 
 |     return true; | 
 |   } | 
 |   if (ExtOpc == Hexagon::M2_accii || ExtOpc == Hexagon::M2_naccii || | 
 |       ExtOpc == Hexagon::S4_addaddi || ExtOpc == Hexagon::S4_subaddi) { | 
 |     // M2_accii:    add(Rt,add(Rs,V)) (tied) | 
 |     // M2_naccii:   sub(Rt,add(Rs,V)) | 
 |     // S4_addaddi:  add(Rt,add(Rs,V)) | 
 |     // S4_subaddi:  add(Rt,sub(V,Rs)) | 
 |     // Check that Rs and V match the initializer expression. The Rs+V is the | 
 |     // combination that is considered "subexpression" for V, although Rx+V | 
 |     // would also be valid. | 
 | #ifndef NDEBUG | 
 |     bool IsSub = ExtOpc == Hexagon::S4_subaddi; | 
 |     Register Rs = MI.getOperand(IsSub ? 3 : 2); | 
 |     ExtValue V = MI.getOperand(IsSub ? 2 : 3); | 
 |     assert(EV == V && Rs == Ex.Rs && IsSub == Ex.Neg && "Initializer mismatch"); | 
 | #endif | 
 |     unsigned NewOpc = ExtOpc == Hexagon::M2_naccii ? Hexagon::A2_sub | 
 |                                                    : Hexagon::A2_add; | 
 |     BuildMI(MBB, At, dl, HII->get(NewOpc)) | 
 |       .add(MI.getOperand(0)) | 
 |       .add(MI.getOperand(1)) | 
 |       .add(MachineOperand(ExtR)); | 
 |     MBB.erase(MI); | 
 |     return true; | 
 |   } | 
 |  | 
 |   if (MI.mayLoadOrStore()) { | 
 |     unsigned IdxOpc = getRegOffOpcode(ExtOpc); | 
 |     assert(IdxOpc && "Expecting indexed opcode"); | 
 |     MachineInstrBuilder MIB = BuildMI(MBB, At, dl, HII->get(IdxOpc)); | 
 |     // Construct the new indexed instruction. | 
 |     // First, add the def for loads. | 
 |     if (MI.mayLoad()) | 
 |       MIB.add(getLoadResultOp(MI)); | 
 |     // Handle possible predication. | 
 |     if (HII->isPredicated(MI)) | 
 |       MIB.add(getPredicateOp(MI)); | 
 |     // Build the address. | 
 |     MIB.add(MachineOperand(ExtR)); | 
 |     MIB.addImm(Diff); | 
 |     // Add the stored value for stores. | 
 |     if (MI.mayStore()) | 
 |       MIB.add(getStoredValueOp(MI)); | 
 |     MIB.cloneMemRefs(MI); | 
 |     MBB.erase(MI); | 
 |     return true; | 
 |   } | 
 |  | 
 | #ifndef NDEBUG | 
 |   dbgs() << '\n' << PrintInit(ExtI, *HRI) << "  " << MI; | 
 | #endif | 
 |   llvm_unreachable("Unhandled expr replacement"); | 
 |   return false; | 
 | } | 
 |  | 
 | bool HCE::replaceInstr(unsigned Idx, Register ExtR, const ExtenderInit &ExtI) { | 
 |   if (ReplaceLimit.getNumOccurrences()) { | 
 |     if (ReplaceLimit <= ReplaceCounter) | 
 |       return false; | 
 |     ++ReplaceCounter; | 
 |   } | 
 |   const ExtDesc &ED = Extenders[Idx]; | 
 |   assert((!ED.IsDef || ED.Rd.Reg != 0) && "Missing Rd for def"); | 
 |   const ExtValue &DefV = ExtI.first; | 
 |   assert(ExtRoot(ExtValue(ED)) == ExtRoot(DefV) && "Extender root mismatch"); | 
 |   const ExtExpr &DefEx = ExtI.second; | 
 |  | 
 |   ExtValue EV(ED); | 
 |   int32_t Diff = EV.Offset - DefV.Offset; | 
 |   const MachineInstr &MI = *ED.UseMI; | 
 |   LLVM_DEBUG(dbgs() << __func__ << " Idx:" << Idx << " ExtR:" | 
 |                     << PrintRegister(ExtR, *HRI) << " Diff:" << Diff << '\n'); | 
 |  | 
 |   // These two addressing modes must be converted into indexed forms | 
 |   // regardless of what the initializer looks like. | 
 |   bool IsAbs = false, IsAbsSet = false; | 
 |   if (MI.mayLoadOrStore()) { | 
 |     unsigned AM = HII->getAddrMode(MI); | 
 |     IsAbs = AM == HexagonII::Absolute; | 
 |     IsAbsSet = AM == HexagonII::AbsoluteSet; | 
 |   } | 
 |  | 
 |   // If it's a def, remember all operands that need to be updated. | 
 |   // If ED is a def, and Diff is not 0, then all uses of the register Rd | 
 |   // defined by ED must be in the form (Rd, imm), i.e. the immediate offset | 
 |   // must follow the Rd in the operand list. | 
 |   std::vector<std::pair<MachineInstr*,unsigned>> RegOps; | 
 |   if (ED.IsDef && Diff != 0) { | 
 |     for (MachineOperand &Op : MRI->use_operands(ED.Rd.Reg)) { | 
 |       MachineInstr &UI = *Op.getParent(); | 
 |       RegOps.push_back({&UI, getOperandIndex(UI, Op)}); | 
 |     } | 
 |   } | 
 |  | 
 |   // Replace the instruction. | 
 |   bool Replaced = false; | 
 |   if (Diff == 0 && DefEx.trivial() && !IsAbs && !IsAbsSet) | 
 |     Replaced = replaceInstrExact(ED, ExtR); | 
 |   else | 
 |     Replaced = replaceInstrExpr(ED, ExtI, ExtR, Diff); | 
 |  | 
 |   if (Diff != 0 && Replaced && ED.IsDef) { | 
 |     // Update offsets of the def's uses. | 
 |     for (std::pair<MachineInstr*,unsigned> P : RegOps) { | 
 |       unsigned J = P.second; | 
 |       assert(P.first->getNumOperands() > J+1 && | 
 |              P.first->getOperand(J+1).isImm()); | 
 |       MachineOperand &ImmOp = P.first->getOperand(J+1); | 
 |       ImmOp.setImm(ImmOp.getImm() + Diff); | 
 |     } | 
 |     // If it was an absolute-set instruction, the "set" part has been removed. | 
 |     // ExtR will now be the register with the extended value, and since all | 
 |     // users of Rd have been updated, all that needs to be done is to replace | 
 |     // Rd with ExtR. | 
 |     if (IsAbsSet) { | 
 |       assert(ED.Rd.Sub == 0 && ExtR.Sub == 0); | 
 |       MRI->replaceRegWith(ED.Rd.Reg, ExtR.Reg); | 
 |     } | 
 |   } | 
 |  | 
 |   return Replaced; | 
 | } | 
 |  | 
 | bool HCE::replaceExtenders(const AssignmentMap &IMap) { | 
 |   LocDefList Defs; | 
 |   bool Changed = false; | 
 |  | 
 |   for (const std::pair<const ExtenderInit, IndexList> &P : IMap) { | 
 |     const IndexList &Idxs = P.second; | 
 |     if (Idxs.size() < CountThreshold) | 
 |       continue; | 
 |  | 
 |     Defs.clear(); | 
 |     calculatePlacement(P.first, Idxs, Defs); | 
 |     for (const std::pair<Loc,IndexList> &Q : Defs) { | 
 |       Register DefR = insertInitializer(Q.first, P.first); | 
 |       NewRegs.push_back(DefR.Reg); | 
 |       for (unsigned I : Q.second) | 
 |         Changed |= replaceInstr(I, DefR, P.first); | 
 |     } | 
 |   } | 
 |   return Changed; | 
 | } | 
 |  | 
 | unsigned HCE::getOperandIndex(const MachineInstr &MI, | 
 |       const MachineOperand &Op) const { | 
 |   for (unsigned i = 0, n = MI.getNumOperands(); i != n; ++i) | 
 |     if (&MI.getOperand(i) == &Op) | 
 |       return i; | 
 |   llvm_unreachable("Not an operand of MI"); | 
 | } | 
 |  | 
 | const MachineOperand &HCE::getPredicateOp(const MachineInstr &MI) const { | 
 |   assert(HII->isPredicated(MI)); | 
 |   for (const MachineOperand &Op : MI.operands()) { | 
 |     if (!Op.isReg() || !Op.isUse() || | 
 |         MRI->getRegClass(Op.getReg()) != &Hexagon::PredRegsRegClass) | 
 |       continue; | 
 |     assert(Op.getSubReg() == 0 && "Predicate register with a subregister"); | 
 |     return Op; | 
 |   } | 
 |   llvm_unreachable("Predicate operand not found"); | 
 | } | 
 |  | 
 | const MachineOperand &HCE::getLoadResultOp(const MachineInstr &MI) const { | 
 |   assert(MI.mayLoad()); | 
 |   return MI.getOperand(0); | 
 | } | 
 |  | 
 | const MachineOperand &HCE::getStoredValueOp(const MachineInstr &MI) const { | 
 |   assert(MI.mayStore()); | 
 |   return MI.getOperand(MI.getNumExplicitOperands()-1); | 
 | } | 
 |  | 
 | bool HCE::runOnMachineFunction(MachineFunction &MF) { | 
 |   if (skipFunction(MF.getFunction())) | 
 |     return false; | 
 |   if (MF.getFunction().hasPersonalityFn()) { | 
 |     LLVM_DEBUG(dbgs() << getPassName() << ": skipping " << MF.getName() | 
 |                       << " due to exception handling\n"); | 
 |     return false; | 
 |   } | 
 |   LLVM_DEBUG(MF.print(dbgs() << "Before " << getPassName() << '\n', nullptr)); | 
 |  | 
 |   HST = &MF.getSubtarget<HexagonSubtarget>(); | 
 |   HII = HST->getInstrInfo(); | 
 |   HRI = HST->getRegisterInfo(); | 
 |   MDT = &getAnalysis<MachineDominatorTree>(); | 
 |   MRI = &MF.getRegInfo(); | 
 |   AssignmentMap IMap; | 
 |  | 
 |   collect(MF); | 
 |   llvm::sort(Extenders, [this](const ExtDesc &A, const ExtDesc &B) { | 
 |     ExtValue VA(A), VB(B); | 
 |     if (VA != VB) | 
 |       return VA < VB; | 
 |     const MachineInstr *MA = A.UseMI; | 
 |     const MachineInstr *MB = B.UseMI; | 
 |     if (MA == MB) { | 
 |       // If it's the same instruction, compare operand numbers. | 
 |       return A.OpNum < B.OpNum; | 
 |     } | 
 |  | 
 |     const MachineBasicBlock *BA = MA->getParent(); | 
 |     const MachineBasicBlock *BB = MB->getParent(); | 
 |     assert(BA->getNumber() != -1 && BB->getNumber() != -1); | 
 |     if (BA != BB) | 
 |       return BA->getNumber() < BB->getNumber(); | 
 |     return MDT->dominates(MA, MB); | 
 |   }); | 
 |  | 
 |   bool Changed = false; | 
 |   LLVM_DEBUG(dbgs() << "Collected " << Extenders.size() << " extenders\n"); | 
 |   for (unsigned I = 0, E = Extenders.size(); I != E; ) { | 
 |     unsigned B = I; | 
 |     const ExtRoot &T = Extenders[B].getOp(); | 
 |     while (I != E && ExtRoot(Extenders[I].getOp()) == T) | 
 |       ++I; | 
 |  | 
 |     IMap.clear(); | 
 |     assignInits(T, B, I, IMap); | 
 |     Changed |= replaceExtenders(IMap); | 
 |   } | 
 |  | 
 |   LLVM_DEBUG({ | 
 |     if (Changed) | 
 |       MF.print(dbgs() << "After " << getPassName() << '\n', nullptr); | 
 |     else | 
 |       dbgs() << "No changes\n"; | 
 |   }); | 
 |   return Changed; | 
 | } | 
 |  | 
 | FunctionPass *llvm::createHexagonConstExtenders() { | 
 |   return new HexagonConstExtenders(); | 
 | } |