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/ADT/StringRef.h" 17#include "llvm/MC/MCInstrDesc.h" 18#include <cassert> 19 20namespace llvm { 21 22class MCSubtargetInfo; 23 24//--------------------------------------------------------------------------- 25/// Interface to description of machine instruction set. 26class MCInstrInfo { 27public: 28 using ComplexDeprecationPredicate = bool (*)(MCInst &, 29 const MCSubtargetInfo &, 30 std::string &); 31 32private: 33 const MCInstrDesc *LastDesc; // Raw array to allow static init'n 34 const unsigned *InstrNameIndices; // Array for name indices in InstrNameData 35 const char *InstrNameData; // Instruction name string pool 36 // Subtarget feature that an instruction is deprecated on, if any 37 // -1 implies this is not deprecated by any single feature. It may still be 38 // deprecated due to a "complex" reason, below. 39 const uint8_t *DeprecatedFeatures; 40 // A complex method to determine if a certain instruction is deprecated or 41 // not, and return the reason for deprecation. 42 const ComplexDeprecationPredicate *ComplexDeprecationInfos; 43 unsigned NumOpcodes; // Number of entries in the desc array 44 45public: 46 /// Initialize MCInstrInfo, called by TableGen auto-generated routines. 47 /// *DO NOT USE*. 48 void InitMCInstrInfo(const MCInstrDesc *D, const unsigned *NI, const char *ND, 49 const uint8_t *DF, 50 const ComplexDeprecationPredicate *CDI, unsigned NO) { 51 LastDesc = D + NO - 1; 52 InstrNameIndices = NI; 53 InstrNameData = ND; 54 DeprecatedFeatures = DF; 55 ComplexDeprecationInfos = CDI; 56 NumOpcodes = NO; 57 } 58 59 unsigned getNumOpcodes() const { return NumOpcodes; } 60 61 /// Return the machine instruction descriptor that corresponds to the 62 /// specified instruction opcode. 63 const MCInstrDesc &get(unsigned Opcode) const { 64 assert(Opcode < NumOpcodes && "Invalid opcode!"); 65 // The table is indexed backwards from the last entry. 66 return *(LastDesc - Opcode); 67 } 68 69 /// Returns the name for the instructions with the given opcode. 70 StringRef getName(unsigned Opcode) const { 71 assert(Opcode < NumOpcodes && "Invalid opcode!"); 72 return StringRef(&InstrNameData[InstrNameIndices[Opcode]]); 73 } 74 75 /// Returns true if a certain instruction is deprecated and if so 76 /// returns the reason in \p Info. 77 bool getDeprecatedInfo(MCInst &MI, const MCSubtargetInfo &STI, 78 std::string &Info) const; 79}; 80 81} // End llvm namespace 82 83#endif 84