utils/TableGen/X86DisassemblerShared.h

   1 //===- X86DisassemblerShared.h - Emitter shared header ----------*- C++ -*-===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9
  10 #ifndef LLVM_UTILS_TABLEGEN_X86DISASSEMBLERSHARED_H
  11 #define LLVM_UTILS_TABLEGEN_X86DISASSEMBLERSHARED_H
  12
  13 #include <cstring>
  14 #include <string>
  15
  16 #include "llvm/Support/X86DisassemblerDecoderCommon.h"
  17
  18 struct InstructionSpecifier {
  19   llvm::X86Disassembler::OperandSpecifier
  20       operands[llvm::X86Disassembler::X86_MAX_OPERANDS];
  21   llvm::X86Disassembler::InstructionContext insnContext;
  22   std::string name;
  23
  24   InstructionSpecifier() {
  25     insnContext = llvm::X86Disassembler::IC;
  26     name = "";
  27     memset(operands, 0, sizeof(operands));
  28   }
  29 };
  30
  31 /// Specifies whether a ModR/M byte is needed and (if so) which
  32 /// instruction each possible value of the ModR/M byte corresponds to. Once
  33 /// this information is known, we have narrowed down to a single instruction.
  34 struct ModRMDecision {
  35   uint8_t modrm_type;
  36   llvm::X86Disassembler::InstrUID instructionIDs[256];
  37 };
  38
  39 /// Specifies which set of ModR/M->instruction tables to look at
  40 /// given a particular opcode.
  41 struct OpcodeDecision {
  42   ModRMDecision modRMDecisions[256];
  43 };
  44
  45 /// Specifies which opcode->instruction tables to look at given
  46 /// a particular context (set of attributes).  Since there are many possible
  47 /// contexts, the decoder first uses CONTEXTS_SYM to determine which context
  48 /// applies given a specific set of attributes.  Hence there are only IC_max
  49 /// entries in this table, rather than 2^(ATTR_max).
  50 struct ContextDecision {
  51   OpcodeDecision opcodeDecisions[llvm::X86Disassembler::IC_max];
  52
  53   ContextDecision() {
  54     memset(opcodeDecisions, 0, sizeof(opcodeDecisions));
  55   }
  56 };
  57
  58 #endif