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 class ScheduleHazardRecognizer;
22 
23 class Thumb2InstrInfo : public ARMBaseInstrInfo {
24   ThumbRegisterInfo RI;
25 public:
26   explicit Thumb2InstrInfo(const ARMSubtarget &STI);
27 
28   /// Return the noop instruction to use for a noop.
29   void getNoop(MCInst &NopInst) const override;
30 
31   // Return the non-pre/post incrementing version of 'Opc'. Return 0
32   // if there is not such an opcode.
33   unsigned getUnindexedOpcode(unsigned Opc) const override;
34 
35   void ReplaceTailWithBranchTo(MachineBasicBlock::iterator Tail,
36                                MachineBasicBlock *NewDest) const override;
37 
38   bool isLegalToSplitMBBAt(MachineBasicBlock &MBB,
39                            MachineBasicBlock::iterator MBBI) const override;
40 
41   void copyPhysReg(MachineBasicBlock &MBB, MachineBasicBlock::iterator I,
42                    const DebugLoc &DL, MCRegister DestReg, MCRegister SrcReg,
43                    bool KillSrc) const override;
44 
45   void storeRegToStackSlot(MachineBasicBlock &MBB,
46                            MachineBasicBlock::iterator MBBI,
47                            Register SrcReg, bool isKill, int FrameIndex,
48                            const TargetRegisterClass *RC,
49                            const TargetRegisterInfo *TRI) const override;
50 
51   void loadRegFromStackSlot(MachineBasicBlock &MBB,
52                             MachineBasicBlock::iterator MBBI,
53                             Register DestReg, int FrameIndex,
54                             const TargetRegisterClass *RC,
55                             const TargetRegisterInfo *TRI) 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