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 X86DISASSEMBLERSHARED_H
11 #define X86DISASSEMBLERSHARED_H
12 
13 #include <string.h>
14 #include <string>
15 
16 #include "../../lib/Target/X86/Disassembler/X86DisassemblerDecoderCommon.h"
17 
18 struct InstructionSpecifier {
19   llvm::X86Disassembler::OperandSpecifier operands[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 
53 #endif
54