1 //===-- Thumb2InstrInfo.h - Thumb-2 Instruction Information -----*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This file contains the Thumb-2 implementation of the TargetInstrInfo class.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_LIB_TARGET_ARM_THUMB2INSTRINFO_H
14 #define LLVM_LIB_TARGET_ARM_THUMB2INSTRINFO_H
15 
16 #include "ARMBaseInstrInfo.h"
17 #include "ThumbRegisterInfo.h"
18 
19 namespace llvm {
20 class ARMSubtarget;
21 
22 class Thumb2InstrInfo : public ARMBaseInstrInfo {
23   ThumbRegisterInfo RI;
24 public:
25   explicit Thumb2InstrInfo(const ARMSubtarget &STI);
26 
27   /// Return the noop instruction to use for a noop.
28   MCInst getNop() const override;
29 
30   // Return the non-pre/post incrementing version of 'Opc'. Return 0
31   // if there is not such an opcode.
32   unsigned getUnindexedOpcode(unsigned Opc) const override;
33 
34   void ReplaceTailWithBranchTo(MachineBasicBlock::iterator Tail,
35                                MachineBasicBlock *NewDest) const override;
36 
37   bool isLegalToSplitMBBAt(MachineBasicBlock &MBB,
38                            MachineBasicBlock::iterator MBBI) const override;
39 
40   void copyPhysReg(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
41                    const DebugLoc &DL, MCRegister DestReg, MCRegister SrcReg,
42                    bool KillSrc) const override;
43 
44   void storeRegToStackSlot(MachineBasicBlock &MBB,
45                            MachineBasicBlock::iterator MBBI, Register SrcReg,
46                            bool isKill, int FrameIndex,
47                            const TargetRegisterClass *RC,
48                            const TargetRegisterInfo *TRI,
49                            Register VReg) const override;
50 
51   void loadRegFromStackSlot(MachineBasicBlock &MBB,
52                             MachineBasicBlock::iterator MBBI, Register DestReg,
53                             int FrameIndex, const TargetRegisterClass *RC,
54                             const TargetRegisterInfo *TRI,
55                             Register VReg) const override;
56 
57   /// getRegisterInfo - TargetInstrInfo is a superset of MRegister info.  As
58   /// such, whenever a client has an instance of instruction info, it should
59   /// always be able to get register info as well (through this method).
60   ///
61   const ThumbRegisterInfo &getRegisterInfo() const override { return RI; }
62 
63   MachineInstr *optimizeSelect(MachineInstr &MI,
64                                SmallPtrSetImpl<MachineInstr *> &SeenMIs,
65                                bool) const override;
66 
67   MachineInstr *commuteInstructionImpl(MachineInstr &MI, bool NewMI,
68                                        unsigned OpIdx1,
69                                        unsigned OpIdx2) const override;
70 
71 private:
72   void expandLoadStackGuard(MachineBasicBlock::iterator MI) const override;
73 };
74 
75 /// getITInstrPredicate - Valid only in Thumb2 mode. This function is identical
76 /// to llvm::getInstrPredicate except it returns AL for conditional branch
77 /// instructions which are "predicated", but are not in IT blocks.
78 ARMCC::CondCodes getITInstrPredicate(const MachineInstr &MI, Register &PredReg);
79 
80 // getVPTInstrPredicate: VPT analogue of that, plus a helper function
81 // corresponding to MachineInstr::findFirstPredOperandIdx.
82 int findFirstVPTPredOperandIdx(const MachineInstr &MI);
83 ARMVCC::VPTCodes getVPTInstrPredicate(const MachineInstr &MI,
84                                       Register &PredReg);
85 inline ARMVCC::VPTCodes getVPTInstrPredicate(const MachineInstr &MI) {
86   Register PredReg;
87   return getVPTInstrPredicate(MI, PredReg);
88 }
89 
90 // Recomputes the Block Mask of Instr, a VPT or VPST instruction.
91 // This rebuilds the block mask of the instruction depending on the predicates
92 // of the instructions following it. This should only be used after the
93 // MVEVPTBlockInsertion pass has run, and should be used whenever a predicated
94 // instruction is added to/removed from the block.
95 void recomputeVPTBlockMask(MachineInstr &Instr);
96 } // namespace llvm
97 
98 #endif
99