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