X86DisassemblerDecoderCommon.h revision a21e2eae3def2fe39caed861dcb73c76c715569b
1/*===- X86DisassemblerDecoderCommon.h - Disassembler decoder -------*- 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 * This file is part of the X86 Disassembler.
11 * It contains common definitions used by both the disassembler and the table
12 *  generator.
13 * Documentation for the disassembler can be found in X86Disassembler.h.
14 *
15 *===----------------------------------------------------------------------===*/
16
17/*
18 * This header file provides those definitions that need to be shared between
19 * the decoder and the table generator in a C-friendly manner.
20 */
21
22#ifndef X86DISASSEMBLERDECODERCOMMON_H
23#define X86DISASSEMBLERDECODERCOMMON_H
24
25#include "llvm/Support/DataTypes.h"
26
27#define INSTRUCTIONS_SYM  x86DisassemblerInstrSpecifiers
28#define CONTEXTS_SYM      x86DisassemblerContexts
29#define ONEBYTE_SYM       x86DisassemblerOneByteOpcodes
30#define TWOBYTE_SYM       x86DisassemblerTwoByteOpcodes
31#define THREEBYTE38_SYM   x86DisassemblerThreeByte38Opcodes
32#define THREEBYTE3A_SYM   x86DisassemblerThreeByte3AOpcodes
33
34#define INSTRUCTIONS_STR  "x86DisassemblerInstrSpecifiers"
35#define CONTEXTS_STR      "x86DisassemblerContexts"
36#define ONEBYTE_STR       "x86DisassemblerOneByteOpcodes"
37#define TWOBYTE_STR       "x86DisassemblerTwoByteOpcodes"
38#define THREEBYTE38_STR   "x86DisassemblerThreeByte38Opcodes"
39#define THREEBYTE3A_STR   "x86DisassemblerThreeByte3AOpcodes"
40
41/*
42 * Attributes of an instruction that must be known before the opcode can be
43 * processed correctly.  Most of these indicate the presence of particular
44 * prefixes, but ATTR_64BIT is simply an attribute of the decoding context.
45 */
46#define ATTRIBUTE_BITS          \
47  ENUM_ENTRY(ATTR_NONE,   0x00) \
48  ENUM_ENTRY(ATTR_64BIT,  0x01) \
49  ENUM_ENTRY(ATTR_XS,     0x02) \
50  ENUM_ENTRY(ATTR_XD,     0x04) \
51  ENUM_ENTRY(ATTR_REXW,   0x08) \
52  ENUM_ENTRY(ATTR_OPSIZE, 0x10) \
53  ENUM_ENTRY(ATTR_VEX,    0x20) \
54  ENUM_ENTRY(ATTR_VEXL,   0x40)
55
56#define ENUM_ENTRY(n, v) n = v,
57enum attributeBits {
58  ATTRIBUTE_BITS
59  ATTR_max
60};
61#undef ENUM_ENTRY
62
63/*
64 * Combinations of the above attributes that are relevant to instruction
65 * decode.  Although other combinations are possible, they can be reduced to
66 * these without affecting the ultimately decoded instruction.
67 */
68
69/*           Class name           Rank  Rationale for rank assignment         */
70#define INSTRUCTION_CONTEXTS                                                   \
71  ENUM_ENTRY(IC,                    0,  "says nothing about the instruction")  \
72  ENUM_ENTRY(IC_64BIT,              1,  "says the instruction applies in "     \
73                                        "64-bit mode but no more")             \
74  ENUM_ENTRY(IC_OPSIZE,             3,  "requires an OPSIZE prefix, so "       \
75                                        "operands change width")               \
76  ENUM_ENTRY(IC_XD,                 2,  "may say something about the opcode "  \
77                                        "but not the operands")                \
78  ENUM_ENTRY(IC_XS,                 2,  "may say something about the opcode "  \
79                                        "but not the operands")                \
80  ENUM_ENTRY(IC_64BIT_REXW,         4,  "requires a REX.W prefix, so operands "\
81                                        "change width; overrides IC_OPSIZE")   \
82  ENUM_ENTRY(IC_64BIT_OPSIZE,       3,  "Just as meaningful as IC_OPSIZE")     \
83  ENUM_ENTRY(IC_64BIT_XD,           5,  "XD instructions are SSE; REX.W is "   \
84                                        "secondary")                           \
85  ENUM_ENTRY(IC_64BIT_XS,           5,  "Just as meaningful as IC_64BIT_XD")   \
86  ENUM_ENTRY(IC_64BIT_REXW_XS,      6,  "OPSIZE could mean a different "       \
87                                        "opcode")                              \
88  ENUM_ENTRY(IC_64BIT_REXW_XD,      6,  "Just as meaningful as "               \
89                                        "IC_64BIT_REXW_XS")                    \
90  ENUM_ENTRY(IC_64BIT_REXW_OPSIZE,  7,  "The Dynamic Duo!  Prefer over all "   \
91                                        "else because this changes most "      \
92                                        "operands' meaning")                   \
93  ENUM_ENTRY(IC_VEX,                1,  "requires a VEX prefix")               \
94  ENUM_ENTRY(IC_VEX_XS,             2,  "requires VEX and the XS prefix")      \
95  ENUM_ENTRY(IC_VEX_XD,             2,  "requires VEX and the XD prefix")      \
96  ENUM_ENTRY(IC_VEX_OPSIZE,         2,  "requires VEX and the OpSize prefix")  \
97  ENUM_ENTRY(IC_VEX_W,              3,  "requires VEX and the W prefix")       \
98  ENUM_ENTRY(IC_VEX_W_XS,           4,  "requires VEX, W, and XS prefix")      \
99  ENUM_ENTRY(IC_VEX_W_XD,           4,  "requires VEX, W, and XD prefix")      \
100  ENUM_ENTRY(IC_VEX_W_OPSIZE,       4,  "requires VEX, W, and OpSize")         \
101  ENUM_ENTRY(IC_VEX_L,              3,  "requires VEX and the L prefix")       \
102  ENUM_ENTRY(IC_VEX_L_XS,           4,  "requires VEX and the L and XS prefix")\
103  ENUM_ENTRY(IC_VEX_L_XD,           4,  "requires VEX and the L and XS prefix")\
104  ENUM_ENTRY(IC_VEX_L_OPSIZE,       4,  "requires VEX, L, and OpSize")
105
106
107#define ENUM_ENTRY(n, r, d) n,
108typedef enum {
109  INSTRUCTION_CONTEXTS
110  IC_max
111} InstructionContext;
112#undef ENUM_ENTRY
113
114/*
115 * Opcode types, which determine which decode table to use, both in the Intel
116 * manual and also for the decoder.
117 */
118typedef enum {
119  ONEBYTE       = 0,
120  TWOBYTE       = 1,
121  THREEBYTE_38  = 2,
122  THREEBYTE_3A  = 3
123} OpcodeType;
124
125/*
126 * The following structs are used for the hierarchical decode table.  After
127 * determining the instruction's class (i.e., which IC_* constant applies to
128 * it), the decoder reads the opcode.  Some instructions require specific
129 * values of the ModR/M byte, so the ModR/M byte indexes into the final table.
130 *
131 * If a ModR/M byte is not required, "required" is left unset, and the values
132 * for each instructionID are identical.
133 */
134
135typedef uint16_t InstrUID;
136
137/*
138 * ModRMDecisionType - describes the type of ModR/M decision, allowing the
139 * consumer to determine the number of entries in it.
140 *
141 * MODRM_ONEENTRY - No matter what the value of the ModR/M byte is, the decoded
142 *                  instruction is the same.
143 * MODRM_SPLITRM  - If the ModR/M byte is between 0x00 and 0xbf, the opcode
144 *                  corresponds to one instruction; otherwise, it corresponds to
145 *                  a different instruction.
146 * MODRM_FULL     - Potentially, each value of the ModR/M byte could correspond
147 *                  to a different instruction.
148 */
149
150#define MODRMTYPES            \
151  ENUM_ENTRY(MODRM_ONEENTRY)  \
152  ENUM_ENTRY(MODRM_SPLITRM)   \
153  ENUM_ENTRY(MODRM_FULL)
154
155#define ENUM_ENTRY(n) n,
156typedef enum {
157  MODRMTYPES
158  MODRM_max
159} ModRMDecisionType;
160#undef ENUM_ENTRY
161
162/*
163 * ModRMDecision - Specifies whether a ModR/M byte is needed and (if so) which
164 *  instruction each possible value of the ModR/M byte corresponds to.  Once
165 *  this information is known, we have narrowed down to a single instruction.
166 */
167struct ModRMDecision {
168  uint8_t     modrm_type;
169
170  /* The macro below must be defined wherever this file is included. */
171  INSTRUCTION_IDS
172};
173
174/*
175 * OpcodeDecision - Specifies which set of ModR/M->instruction tables to look at
176 *   given a particular opcode.
177 */
178struct OpcodeDecision {
179  struct ModRMDecision modRMDecisions[256];
180};
181
182/*
183 * ContextDecision - Specifies which opcode->instruction tables to look at given
184 *   a particular context (set of attributes).  Since there are many possible
185 *   contexts, the decoder first uses CONTEXTS_SYM to determine which context
186 *   applies given a specific set of attributes.  Hence there are only IC_max
187 *   entries in this table, rather than 2^(ATTR_max).
188 */
189struct ContextDecision {
190  struct OpcodeDecision opcodeDecisions[IC_max];
191};
192
193/*
194 * Physical encodings of instruction operands.
195 */
196
197#define ENCODINGS                                                              \
198  ENUM_ENTRY(ENCODING_NONE,   "")                                              \
199  ENUM_ENTRY(ENCODING_REG,    "Register operand in ModR/M byte.")              \
200  ENUM_ENTRY(ENCODING_RM,     "R/M operand in ModR/M byte.")                   \
201  ENUM_ENTRY(ENCODING_VVVV,   "Register operand in VEX.vvvv byte.")            \
202  ENUM_ENTRY(ENCODING_CB,     "1-byte code offset (possible new CS value)")    \
203  ENUM_ENTRY(ENCODING_CW,     "2-byte")                                        \
204  ENUM_ENTRY(ENCODING_CD,     "4-byte")                                        \
205  ENUM_ENTRY(ENCODING_CP,     "6-byte")                                        \
206  ENUM_ENTRY(ENCODING_CO,     "8-byte")                                        \
207  ENUM_ENTRY(ENCODING_CT,     "10-byte")                                       \
208  ENUM_ENTRY(ENCODING_IB,     "1-byte immediate")                              \
209  ENUM_ENTRY(ENCODING_IW,     "2-byte")                                        \
210  ENUM_ENTRY(ENCODING_ID,     "4-byte")                                        \
211  ENUM_ENTRY(ENCODING_IO,     "8-byte")                                        \
212  ENUM_ENTRY(ENCODING_RB,     "(AL..DIL, R8L..R15L) Register code added to "   \
213                              "the opcode byte")                               \
214  ENUM_ENTRY(ENCODING_RW,     "(AX..DI, R8W..R15W)")                           \
215  ENUM_ENTRY(ENCODING_RD,     "(EAX..EDI, R8D..R15D)")                         \
216  ENUM_ENTRY(ENCODING_RO,     "(RAX..RDI, R8..R15)")                           \
217  ENUM_ENTRY(ENCODING_I,      "Position on floating-point stack added to the " \
218                              "opcode byte")                                   \
219                                                                               \
220  ENUM_ENTRY(ENCODING_Iv,     "Immediate of operand size")                     \
221  ENUM_ENTRY(ENCODING_Ia,     "Immediate of address size")                     \
222  ENUM_ENTRY(ENCODING_Rv,     "Register code of operand size added to the "    \
223                              "opcode byte")                                   \
224  ENUM_ENTRY(ENCODING_DUP,    "Duplicate of another operand; ID is encoded "   \
225                              "in type")
226
227#define ENUM_ENTRY(n, d) n,
228  typedef enum {
229    ENCODINGS
230    ENCODING_max
231  } OperandEncoding;
232#undef ENUM_ENTRY
233
234/*
235 * Semantic interpretations of instruction operands.
236 */
237
238#define TYPES                                                                  \
239  ENUM_ENTRY(TYPE_NONE,       "")                                              \
240  ENUM_ENTRY(TYPE_REL8,       "1-byte immediate address")                      \
241  ENUM_ENTRY(TYPE_REL16,      "2-byte")                                        \
242  ENUM_ENTRY(TYPE_REL32,      "4-byte")                                        \
243  ENUM_ENTRY(TYPE_REL64,      "8-byte")                                        \
244  ENUM_ENTRY(TYPE_PTR1616,    "2+2-byte segment+offset address")               \
245  ENUM_ENTRY(TYPE_PTR1632,    "2+4-byte")                                      \
246  ENUM_ENTRY(TYPE_PTR1664,    "2+8-byte")                                      \
247  ENUM_ENTRY(TYPE_R8,         "1-byte register operand")                       \
248  ENUM_ENTRY(TYPE_R16,        "2-byte")                                        \
249  ENUM_ENTRY(TYPE_R32,        "4-byte")                                        \
250  ENUM_ENTRY(TYPE_R64,        "8-byte")                                        \
251  ENUM_ENTRY(TYPE_IMM8,       "1-byte immediate operand")                      \
252  ENUM_ENTRY(TYPE_IMM16,      "2-byte")                                        \
253  ENUM_ENTRY(TYPE_IMM32,      "4-byte")                                        \
254  ENUM_ENTRY(TYPE_IMM64,      "8-byte")                                        \
255  ENUM_ENTRY(TYPE_IMM3,       "1-byte immediate operand between 0 and 7")      \
256  ENUM_ENTRY(TYPE_RM8,        "1-byte register or memory operand")             \
257  ENUM_ENTRY(TYPE_RM16,       "2-byte")                                        \
258  ENUM_ENTRY(TYPE_RM32,       "4-byte")                                        \
259  ENUM_ENTRY(TYPE_RM64,       "8-byte")                                        \
260  ENUM_ENTRY(TYPE_M,          "Memory operand")                                \
261  ENUM_ENTRY(TYPE_M8,         "1-byte")                                        \
262  ENUM_ENTRY(TYPE_M16,        "2-byte")                                        \
263  ENUM_ENTRY(TYPE_M32,        "4-byte")                                        \
264  ENUM_ENTRY(TYPE_M64,        "8-byte")                                        \
265  ENUM_ENTRY(TYPE_LEA,        "Effective address")                             \
266  ENUM_ENTRY(TYPE_M128,       "16-byte (SSE/SSE2)")                            \
267  ENUM_ENTRY(TYPE_M256,       "256-byte (AVX)")                                \
268  ENUM_ENTRY(TYPE_M1616,      "2+2-byte segment+offset address")               \
269  ENUM_ENTRY(TYPE_M1632,      "2+4-byte")                                      \
270  ENUM_ENTRY(TYPE_M1664,      "2+8-byte")                                      \
271  ENUM_ENTRY(TYPE_M16_32,     "2+4-byte two-part memory operand (LIDT, LGDT)") \
272  ENUM_ENTRY(TYPE_M16_16,     "2+2-byte (BOUND)")                              \
273  ENUM_ENTRY(TYPE_M32_32,     "4+4-byte (BOUND)")                              \
274  ENUM_ENTRY(TYPE_M16_64,     "2+8-byte (LIDT, LGDT)")                         \
275  ENUM_ENTRY(TYPE_MOFFS8,     "1-byte memory offset (relative to segment "     \
276                              "base)")                                         \
277  ENUM_ENTRY(TYPE_MOFFS16,    "2-byte")                                        \
278  ENUM_ENTRY(TYPE_MOFFS32,    "4-byte")                                        \
279  ENUM_ENTRY(TYPE_MOFFS64,    "8-byte")                                        \
280  ENUM_ENTRY(TYPE_SREG,       "Byte with single bit set: 0 = ES, 1 = CS, "     \
281                              "2 = SS, 3 = DS, 4 = FS, 5 = GS")                \
282  ENUM_ENTRY(TYPE_M32FP,      "32-bit IEE754 memory floating-point operand")   \
283  ENUM_ENTRY(TYPE_M64FP,      "64-bit")                                        \
284  ENUM_ENTRY(TYPE_M80FP,      "80-bit extended")                               \
285  ENUM_ENTRY(TYPE_M16INT,     "2-byte memory integer operand for use in "      \
286                              "floating-point instructions")                   \
287  ENUM_ENTRY(TYPE_M32INT,     "4-byte")                                        \
288  ENUM_ENTRY(TYPE_M64INT,     "8-byte")                                        \
289  ENUM_ENTRY(TYPE_ST,         "Position on the floating-point stack")          \
290  ENUM_ENTRY(TYPE_MM,         "MMX register operand")                          \
291  ENUM_ENTRY(TYPE_MM32,       "4-byte MMX register or memory operand")         \
292  ENUM_ENTRY(TYPE_MM64,       "8-byte")                                        \
293  ENUM_ENTRY(TYPE_XMM,        "XMM register operand")                          \
294  ENUM_ENTRY(TYPE_XMM32,      "4-byte XMM register or memory operand")         \
295  ENUM_ENTRY(TYPE_XMM64,      "8-byte")                                        \
296  ENUM_ENTRY(TYPE_XMM128,     "16-byte")                                       \
297  ENUM_ENTRY(TYPE_XMM256,     "32-byte")                                       \
298  ENUM_ENTRY(TYPE_XMM0,       "Implicit use of XMM0")                          \
299  ENUM_ENTRY(TYPE_SEGMENTREG, "Segment register operand")                      \
300  ENUM_ENTRY(TYPE_DEBUGREG,   "Debug register operand")                        \
301  ENUM_ENTRY(TYPE_CONTROLREG, "Control register operand")                      \
302                                                                               \
303  ENUM_ENTRY(TYPE_Mv,         "Memory operand of operand size")                \
304  ENUM_ENTRY(TYPE_Rv,         "Register operand of operand size")              \
305  ENUM_ENTRY(TYPE_IMMv,       "Immediate operand of operand size")             \
306  ENUM_ENTRY(TYPE_RELv,       "Immediate address of operand size")             \
307  ENUM_ENTRY(TYPE_DUP0,       "Duplicate of operand 0")                        \
308  ENUM_ENTRY(TYPE_DUP1,       "operand 1")                                     \
309  ENUM_ENTRY(TYPE_DUP2,       "operand 2")                                     \
310  ENUM_ENTRY(TYPE_DUP3,       "operand 3")                                     \
311  ENUM_ENTRY(TYPE_DUP4,       "operand 4")                                     \
312  ENUM_ENTRY(TYPE_M512,       "512-bit FPU/MMX/XMM/MXCSR state")
313
314#define ENUM_ENTRY(n, d) n,
315typedef enum {
316  TYPES
317  TYPE_max
318} OperandType;
319#undef ENUM_ENTRY
320
321/*
322 * OperandSpecifier - The specification for how to extract and interpret one
323 *   operand.
324 */
325struct OperandSpecifier {
326  OperandEncoding  encoding;
327  OperandType      type;
328};
329
330/*
331 * Indicates where the opcode modifier (if any) is to be found.  Extended
332 * opcodes with AddRegFrm have the opcode modifier in the ModR/M byte.
333 */
334
335#define MODIFIER_TYPES        \
336  ENUM_ENTRY(MODIFIER_NONE)   \
337  ENUM_ENTRY(MODIFIER_OPCODE) \
338  ENUM_ENTRY(MODIFIER_MODRM)
339
340#define ENUM_ENTRY(n) n,
341typedef enum {
342  MODIFIER_TYPES
343  MODIFIER_max
344} ModifierType;
345#undef ENUM_ENTRY
346
347#define X86_MAX_OPERANDS 5
348
349/*
350 * The specification for how to extract and interpret a full instruction and
351 * its operands.
352 */
353struct InstructionSpecifier {
354  ModifierType modifierType;
355  uint8_t modifierBase;
356  struct OperandSpecifier operands[X86_MAX_OPERANDS];
357
358  /* The macro below must be defined wherever this file is included. */
359  INSTRUCTION_SPECIFIER_FIELDS
360};
361
362/*
363 * Decoding mode for the Intel disassembler.  16-bit, 32-bit, and 64-bit mode
364 * are supported, and represent real mode, IA-32e, and IA-32e in 64-bit mode,
365 * respectively.
366 */
367typedef enum {
368  MODE_16BIT,
369  MODE_32BIT,
370  MODE_64BIT
371} DisassemblerMode;
372
373#endif
374