1 //===-- llvm/MC/MCInstrInfo.h - Target Instruction Info ---------*- 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 describes the target machine instruction set.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_MC_MCINSTRINFO_H
14 #define LLVM_MC_MCINSTRINFO_H
15 
16 #include "llvm/MC/MCInstrDesc.h"
17 #include <cassert>
18 
19 namespace llvm {
20 
21 class MCSubtargetInfo;
22 
23 //---------------------------------------------------------------------------
24 /// Interface to description of machine instruction set.
25 class MCInstrInfo {
26 public:
27   using ComplexDeprecationPredicate = bool (*)(MCInst &,
28                                                const MCSubtargetInfo &,
29                                                std::string &);
30 
31 private:
32   const MCInstrDesc *Desc;          // Raw array to allow static init'n
33   const unsigned *InstrNameIndices; // Array for name indices in InstrNameData
34   const char *InstrNameData;        // Instruction name string pool
35   // Subtarget feature that an instruction is deprecated on, if any
36   // -1 implies this is not deprecated by any single feature. It may still be
37   // deprecated due to a "complex" reason, below.
38   const uint8_t *DeprecatedFeatures;
39   // A complex method to determine if a certain instruction is deprecated or
40   // not, and return the reason for deprecation.
41   const ComplexDeprecationPredicate *ComplexDeprecationInfos;
42   unsigned NumOpcodes;              // Number of entries in the desc array
43 
44 public:
45   /// Initialize MCInstrInfo, called by TableGen auto-generated routines.
46   /// *DO NOT USE*.
InitMCInstrInfo(const MCInstrDesc * D,const unsigned * NI,const char * ND,const uint8_t * DF,const ComplexDeprecationPredicate * CDI,unsigned NO)47   void InitMCInstrInfo(const MCInstrDesc *D, const unsigned *NI, const char *ND,
48                        const uint8_t *DF,
49                        const ComplexDeprecationPredicate *CDI, unsigned NO) {
50     Desc = D;
51     InstrNameIndices = NI;
52     InstrNameData = ND;
53     DeprecatedFeatures = DF;
54     ComplexDeprecationInfos = CDI;
55     NumOpcodes = NO;
56   }
57 
getNumOpcodes()58   unsigned getNumOpcodes() const { return NumOpcodes; }
59 
60   /// Return the machine instruction descriptor that corresponds to the
61   /// specified instruction opcode.
get(unsigned Opcode)62   const MCInstrDesc &get(unsigned Opcode) const {
63     assert(Opcode < NumOpcodes && "Invalid opcode!");
64     return Desc[Opcode];
65   }
66 
67   /// Returns the name for the instructions with the given opcode.
getName(unsigned Opcode)68   StringRef getName(unsigned Opcode) const {
69     assert(Opcode < NumOpcodes && "Invalid opcode!");
70     return StringRef(&InstrNameData[InstrNameIndices[Opcode]]);
71   }
72 
73   /// Returns true if a certain instruction is deprecated and if so
74   /// returns the reason in \p Info.
75   bool getDeprecatedInfo(MCInst &MI, const MCSubtargetInfo &STI,
76                          std::string &Info) const;
77 };
78 
79 } // End llvm namespace
80 
81 #endif
82