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#define THREEBYTEA6_SYM   x86DisassemblerThreeByteA6Opcodes
34#define THREEBYTEA7_SYM   x86DisassemblerThreeByteA7Opcodes
35
36#define INSTRUCTIONS_STR  "x86DisassemblerInstrSpecifiers"
37#define CONTEXTS_STR      "x86DisassemblerContexts"
38#define ONEBYTE_STR       "x86DisassemblerOneByteOpcodes"
39#define TWOBYTE_STR       "x86DisassemblerTwoByteOpcodes"
40#define THREEBYTE38_STR   "x86DisassemblerThreeByte38Opcodes"
41#define THREEBYTE3A_STR   "x86DisassemblerThreeByte3AOpcodes"
42#define THREEBYTEA6_STR   "x86DisassemblerThreeByteA6Opcodes"
43#define THREEBYTEA7_STR   "x86DisassemblerThreeByteA7Opcodes"
44
45/*
46 * Attributes of an instruction that must be known before the opcode can be
47 * processed correctly.  Most of these indicate the presence of particular
48 * prefixes, but ATTR_64BIT is simply an attribute of the decoding context.
49 */
50#define ATTRIBUTE_BITS          \
51  ENUM_ENTRY(ATTR_NONE,   0x00) \
52  ENUM_ENTRY(ATTR_64BIT,  0x01) \
53  ENUM_ENTRY(ATTR_XS,     0x02) \
54  ENUM_ENTRY(ATTR_XD,     0x04) \
55  ENUM_ENTRY(ATTR_REXW,   0x08) \
56  ENUM_ENTRY(ATTR_OPSIZE, 0x10) \
57  ENUM_ENTRY(ATTR_ADSIZE, 0x20) \
58  ENUM_ENTRY(ATTR_VEX,    0x40) \
59  ENUM_ENTRY(ATTR_VEXL,   0x80)
60
61#define ENUM_ENTRY(n, v) n = v,
62enum attributeBits {
63  ATTRIBUTE_BITS
64  ATTR_max
65};
66#undef ENUM_ENTRY
67
68/*
69 * Combinations of the above attributes that are relevant to instruction
70 * decode.  Although other combinations are possible, they can be reduced to
71 * these without affecting the ultimately decoded instruction.
72 */
73
74/*           Class name           Rank  Rationale for rank assignment         */
75#define INSTRUCTION_CONTEXTS                                                   \
76  ENUM_ENTRY(IC,                    0,  "says nothing about the instruction")  \
77  ENUM_ENTRY(IC_64BIT,              1,  "says the instruction applies in "     \
78                                        "64-bit mode but no more")             \
79  ENUM_ENTRY(IC_OPSIZE,             3,  "requires an OPSIZE prefix, so "       \
80                                        "operands change width")               \
81  ENUM_ENTRY(IC_ADSIZE,             3,  "requires an ADSIZE prefix, so "       \
82                                        "operands change width")               \
83  ENUM_ENTRY(IC_XD,                 2,  "may say something about the opcode "  \
84                                        "but not the operands")                \
85  ENUM_ENTRY(IC_XS,                 2,  "may say something about the opcode "  \
86                                        "but not the operands")                \
87  ENUM_ENTRY(IC_XD_OPSIZE,          3,  "requires an OPSIZE prefix, so "       \
88                                        "operands change width")               \
89  ENUM_ENTRY(IC_XS_OPSIZE,          3,  "requires an OPSIZE prefix, so "       \
90                                        "operands change width")               \
91  ENUM_ENTRY(IC_64BIT_REXW,         4,  "requires a REX.W prefix, so operands "\
92                                        "change width; overrides IC_OPSIZE")   \
93  ENUM_ENTRY(IC_64BIT_OPSIZE,       3,  "Just as meaningful as IC_OPSIZE")     \
94  ENUM_ENTRY(IC_64BIT_ADSIZE,       3,  "Just as meaningful as IC_ADSIZE")     \
95  ENUM_ENTRY(IC_64BIT_XD,           5,  "XD instructions are SSE; REX.W is "   \
96                                        "secondary")                           \
97  ENUM_ENTRY(IC_64BIT_XS,           5,  "Just as meaningful as IC_64BIT_XD")   \
98  ENUM_ENTRY(IC_64BIT_XD_OPSIZE,    3,  "Just as meaningful as IC_XD_OPSIZE")  \
99  ENUM_ENTRY(IC_64BIT_XS_OPSIZE,    3,  "Just as meaningful as IC_XS_OPSIZE")  \
100  ENUM_ENTRY(IC_64BIT_REXW_XS,      6,  "OPSIZE could mean a different "       \
101                                        "opcode")                              \
102  ENUM_ENTRY(IC_64BIT_REXW_XD,      6,  "Just as meaningful as "               \
103                                        "IC_64BIT_REXW_XS")                    \
104  ENUM_ENTRY(IC_64BIT_REXW_OPSIZE,  7,  "The Dynamic Duo!  Prefer over all "   \
105                                        "else because this changes most "      \
106                                        "operands' meaning")                   \
107  ENUM_ENTRY(IC_VEX,                1,  "requires a VEX prefix")               \
108  ENUM_ENTRY(IC_VEX_XS,             2,  "requires VEX and the XS prefix")      \
109  ENUM_ENTRY(IC_VEX_XD,             2,  "requires VEX and the XD prefix")      \
110  ENUM_ENTRY(IC_VEX_OPSIZE,         2,  "requires VEX and the OpSize prefix")  \
111  ENUM_ENTRY(IC_VEX_W,              3,  "requires VEX and the W prefix")       \
112  ENUM_ENTRY(IC_VEX_W_XS,           4,  "requires VEX, W, and XS prefix")      \
113  ENUM_ENTRY(IC_VEX_W_XD,           4,  "requires VEX, W, and XD prefix")      \
114  ENUM_ENTRY(IC_VEX_W_OPSIZE,       4,  "requires VEX, W, and OpSize")         \
115  ENUM_ENTRY(IC_VEX_L,              3,  "requires VEX and the L prefix")       \
116  ENUM_ENTRY(IC_VEX_L_XS,           4,  "requires VEX and the L and XS prefix")\
117  ENUM_ENTRY(IC_VEX_L_XD,           4,  "requires VEX and the L and XD prefix")\
118  ENUM_ENTRY(IC_VEX_L_OPSIZE,       4,  "requires VEX, L, and OpSize")         \
119  ENUM_ENTRY(IC_VEX_L_W_OPSIZE,     5,  "requires VEX, L, W and OpSize")
120
121
122#define ENUM_ENTRY(n, r, d) n,
123typedef enum {
124  INSTRUCTION_CONTEXTS
125  IC_max
126} InstructionContext;
127#undef ENUM_ENTRY
128
129/*
130 * Opcode types, which determine which decode table to use, both in the Intel
131 * manual and also for the decoder.
132 */
133typedef enum {
134  ONEBYTE       = 0,
135  TWOBYTE       = 1,
136  THREEBYTE_38  = 2,
137  THREEBYTE_3A  = 3,
138  THREEBYTE_A6  = 4,
139  THREEBYTE_A7  = 5
140} OpcodeType;
141
142/*
143 * The following structs are used for the hierarchical decode table.  After
144 * determining the instruction's class (i.e., which IC_* constant applies to
145 * it), the decoder reads the opcode.  Some instructions require specific
146 * values of the ModR/M byte, so the ModR/M byte indexes into the final table.
147 *
148 * If a ModR/M byte is not required, "required" is left unset, and the values
149 * for each instructionID are identical.
150 */
151
152typedef uint16_t InstrUID;
153
154/*
155 * ModRMDecisionType - describes the type of ModR/M decision, allowing the
156 * consumer to determine the number of entries in it.
157 *
158 * MODRM_ONEENTRY - No matter what the value of the ModR/M byte is, the decoded
159 *                  instruction is the same.
160 * MODRM_SPLITRM  - If the ModR/M byte is between 0x00 and 0xbf, the opcode
161 *                  corresponds to one instruction; otherwise, it corresponds to
162 *                  a different instruction.
163 * MODRM_SPLITMISC- If the ModR/M byte is between 0x00 and 0xbf, ModR/M byte
164 *                  divided by 8 is used to select instruction; otherwise, each
165 *                  value of the ModR/M byte could correspond to a different
166 *                  instruction.
167 * MODRM_SPLITREG - ModR/M byte divided by 8 is used to select instruction. This
168                    corresponds to instructions that use reg field as opcode
169 * MODRM_FULL     - Potentially, each value of the ModR/M byte could correspond
170 *                  to a different instruction.
171 */
172
173#define MODRMTYPES            \
174  ENUM_ENTRY(MODRM_ONEENTRY)  \
175  ENUM_ENTRY(MODRM_SPLITRM)   \
176  ENUM_ENTRY(MODRM_SPLITMISC)  \
177  ENUM_ENTRY(MODRM_SPLITREG)  \
178  ENUM_ENTRY(MODRM_FULL)
179
180#define ENUM_ENTRY(n) n,
181typedef enum {
182  MODRMTYPES
183  MODRM_max
184} ModRMDecisionType;
185#undef ENUM_ENTRY
186
187/*
188 * ModRMDecision - Specifies whether a ModR/M byte is needed and (if so) which
189 *  instruction each possible value of the ModR/M byte corresponds to.  Once
190 *  this information is known, we have narrowed down to a single instruction.
191 */
192struct ModRMDecision {
193  uint8_t     modrm_type;
194
195  /* The macro below must be defined wherever this file is included. */
196  INSTRUCTION_IDS
197};
198
199/*
200 * OpcodeDecision - Specifies which set of ModR/M->instruction tables to look at
201 *   given a particular opcode.
202 */
203struct OpcodeDecision {
204  struct ModRMDecision modRMDecisions[256];
205};
206
207/*
208 * ContextDecision - Specifies which opcode->instruction tables to look at given
209 *   a particular context (set of attributes).  Since there are many possible
210 *   contexts, the decoder first uses CONTEXTS_SYM to determine which context
211 *   applies given a specific set of attributes.  Hence there are only IC_max
212 *   entries in this table, rather than 2^(ATTR_max).
213 */
214struct ContextDecision {
215  struct OpcodeDecision opcodeDecisions[IC_max];
216};
217
218/*
219 * Physical encodings of instruction operands.
220 */
221
222#define ENCODINGS                                                              \
223  ENUM_ENTRY(ENCODING_NONE,   "")                                              \
224  ENUM_ENTRY(ENCODING_REG,    "Register operand in ModR/M byte.")              \
225  ENUM_ENTRY(ENCODING_RM,     "R/M operand in ModR/M byte.")                   \
226  ENUM_ENTRY(ENCODING_VVVV,   "Register operand in VEX.vvvv byte.")            \
227  ENUM_ENTRY(ENCODING_CB,     "1-byte code offset (possible new CS value)")    \
228  ENUM_ENTRY(ENCODING_CW,     "2-byte")                                        \
229  ENUM_ENTRY(ENCODING_CD,     "4-byte")                                        \
230  ENUM_ENTRY(ENCODING_CP,     "6-byte")                                        \
231  ENUM_ENTRY(ENCODING_CO,     "8-byte")                                        \
232  ENUM_ENTRY(ENCODING_CT,     "10-byte")                                       \
233  ENUM_ENTRY(ENCODING_IB,     "1-byte immediate")                              \
234  ENUM_ENTRY(ENCODING_IW,     "2-byte")                                        \
235  ENUM_ENTRY(ENCODING_ID,     "4-byte")                                        \
236  ENUM_ENTRY(ENCODING_IO,     "8-byte")                                        \
237  ENUM_ENTRY(ENCODING_RB,     "(AL..DIL, R8L..R15L) Register code added to "   \
238                              "the opcode byte")                               \
239  ENUM_ENTRY(ENCODING_RW,     "(AX..DI, R8W..R15W)")                           \
240  ENUM_ENTRY(ENCODING_RD,     "(EAX..EDI, R8D..R15D)")                         \
241  ENUM_ENTRY(ENCODING_RO,     "(RAX..RDI, R8..R15)")                           \
242  ENUM_ENTRY(ENCODING_I,      "Position on floating-point stack added to the " \
243                              "opcode byte")                                   \
244                                                                               \
245  ENUM_ENTRY(ENCODING_Iv,     "Immediate of operand size")                     \
246  ENUM_ENTRY(ENCODING_Ia,     "Immediate of address size")                     \
247  ENUM_ENTRY(ENCODING_Rv,     "Register code of operand size added to the "    \
248                              "opcode byte")                                   \
249  ENUM_ENTRY(ENCODING_DUP,    "Duplicate of another operand; ID is encoded "   \
250                              "in type")
251
252#define ENUM_ENTRY(n, d) n,
253  typedef enum {
254    ENCODINGS
255    ENCODING_max
256  } OperandEncoding;
257#undef ENUM_ENTRY
258
259/*
260 * Semantic interpretations of instruction operands.
261 */
262
263#define TYPES                                                                  \
264  ENUM_ENTRY(TYPE_NONE,       "")                                              \
265  ENUM_ENTRY(TYPE_REL8,       "1-byte immediate address")                      \
266  ENUM_ENTRY(TYPE_REL16,      "2-byte")                                        \
267  ENUM_ENTRY(TYPE_REL32,      "4-byte")                                        \
268  ENUM_ENTRY(TYPE_REL64,      "8-byte")                                        \
269  ENUM_ENTRY(TYPE_PTR1616,    "2+2-byte segment+offset address")               \
270  ENUM_ENTRY(TYPE_PTR1632,    "2+4-byte")                                      \
271  ENUM_ENTRY(TYPE_PTR1664,    "2+8-byte")                                      \
272  ENUM_ENTRY(TYPE_R8,         "1-byte register operand")                       \
273  ENUM_ENTRY(TYPE_R16,        "2-byte")                                        \
274  ENUM_ENTRY(TYPE_R32,        "4-byte")                                        \
275  ENUM_ENTRY(TYPE_R64,        "8-byte")                                        \
276  ENUM_ENTRY(TYPE_IMM8,       "1-byte immediate operand")                      \
277  ENUM_ENTRY(TYPE_IMM16,      "2-byte")                                        \
278  ENUM_ENTRY(TYPE_IMM32,      "4-byte")                                        \
279  ENUM_ENTRY(TYPE_IMM64,      "8-byte")                                        \
280  ENUM_ENTRY(TYPE_IMM3,       "1-byte immediate operand between 0 and 7")      \
281  ENUM_ENTRY(TYPE_IMM5,       "1-byte immediate operand between 0 and 31")     \
282  ENUM_ENTRY(TYPE_RM8,        "1-byte register or memory operand")             \
283  ENUM_ENTRY(TYPE_RM16,       "2-byte")                                        \
284  ENUM_ENTRY(TYPE_RM32,       "4-byte")                                        \
285  ENUM_ENTRY(TYPE_RM64,       "8-byte")                                        \
286  ENUM_ENTRY(TYPE_M,          "Memory operand")                                \
287  ENUM_ENTRY(TYPE_M8,         "1-byte")                                        \
288  ENUM_ENTRY(TYPE_M16,        "2-byte")                                        \
289  ENUM_ENTRY(TYPE_M32,        "4-byte")                                        \
290  ENUM_ENTRY(TYPE_M64,        "8-byte")                                        \
291  ENUM_ENTRY(TYPE_LEA,        "Effective address")                             \
292  ENUM_ENTRY(TYPE_M128,       "16-byte (SSE/SSE2)")                            \
293  ENUM_ENTRY(TYPE_M256,       "256-byte (AVX)")                                \
294  ENUM_ENTRY(TYPE_M1616,      "2+2-byte segment+offset address")               \
295  ENUM_ENTRY(TYPE_M1632,      "2+4-byte")                                      \
296  ENUM_ENTRY(TYPE_M1664,      "2+8-byte")                                      \
297  ENUM_ENTRY(TYPE_M16_32,     "2+4-byte two-part memory operand (LIDT, LGDT)") \
298  ENUM_ENTRY(TYPE_M16_16,     "2+2-byte (BOUND)")                              \
299  ENUM_ENTRY(TYPE_M32_32,     "4+4-byte (BOUND)")                              \
300  ENUM_ENTRY(TYPE_M16_64,     "2+8-byte (LIDT, LGDT)")                         \
301  ENUM_ENTRY(TYPE_MOFFS8,     "1-byte memory offset (relative to segment "     \
302                              "base)")                                         \
303  ENUM_ENTRY(TYPE_MOFFS16,    "2-byte")                                        \
304  ENUM_ENTRY(TYPE_MOFFS32,    "4-byte")                                        \
305  ENUM_ENTRY(TYPE_MOFFS64,    "8-byte")                                        \
306  ENUM_ENTRY(TYPE_SREG,       "Byte with single bit set: 0 = ES, 1 = CS, "     \
307                              "2 = SS, 3 = DS, 4 = FS, 5 = GS")                \
308  ENUM_ENTRY(TYPE_M32FP,      "32-bit IEE754 memory floating-point operand")   \
309  ENUM_ENTRY(TYPE_M64FP,      "64-bit")                                        \
310  ENUM_ENTRY(TYPE_M80FP,      "80-bit extended")                               \
311  ENUM_ENTRY(TYPE_M16INT,     "2-byte memory integer operand for use in "      \
312                              "floating-point instructions")                   \
313  ENUM_ENTRY(TYPE_M32INT,     "4-byte")                                        \
314  ENUM_ENTRY(TYPE_M64INT,     "8-byte")                                        \
315  ENUM_ENTRY(TYPE_ST,         "Position on the floating-point stack")          \
316  ENUM_ENTRY(TYPE_MM,         "MMX register operand")                          \
317  ENUM_ENTRY(TYPE_MM32,       "4-byte MMX register or memory operand")         \
318  ENUM_ENTRY(TYPE_MM64,       "8-byte")                                        \
319  ENUM_ENTRY(TYPE_XMM,        "XMM register operand")                          \
320  ENUM_ENTRY(TYPE_XMM32,      "4-byte XMM register or memory operand")         \
321  ENUM_ENTRY(TYPE_XMM64,      "8-byte")                                        \
322  ENUM_ENTRY(TYPE_XMM128,     "16-byte")                                       \
323  ENUM_ENTRY(TYPE_XMM256,     "32-byte")                                       \
324  ENUM_ENTRY(TYPE_XMM0,       "Implicit use of XMM0")                          \
325  ENUM_ENTRY(TYPE_SEGMENTREG, "Segment register operand")                      \
326  ENUM_ENTRY(TYPE_DEBUGREG,   "Debug register operand")                        \
327  ENUM_ENTRY(TYPE_CONTROLREG, "Control register operand")                      \
328                                                                               \
329  ENUM_ENTRY(TYPE_Mv,         "Memory operand of operand size")                \
330  ENUM_ENTRY(TYPE_Rv,         "Register operand of operand size")              \
331  ENUM_ENTRY(TYPE_IMMv,       "Immediate operand of operand size")             \
332  ENUM_ENTRY(TYPE_RELv,       "Immediate address of operand size")             \
333  ENUM_ENTRY(TYPE_DUP0,       "Duplicate of operand 0")                        \
334  ENUM_ENTRY(TYPE_DUP1,       "operand 1")                                     \
335  ENUM_ENTRY(TYPE_DUP2,       "operand 2")                                     \
336  ENUM_ENTRY(TYPE_DUP3,       "operand 3")                                     \
337  ENUM_ENTRY(TYPE_DUP4,       "operand 4")                                     \
338  ENUM_ENTRY(TYPE_M512,       "512-bit FPU/MMX/XMM/MXCSR state")
339
340#define ENUM_ENTRY(n, d) n,
341typedef enum {
342  TYPES
343  TYPE_max
344} OperandType;
345#undef ENUM_ENTRY
346
347/*
348 * OperandSpecifier - The specification for how to extract and interpret one
349 *   operand.
350 */
351struct OperandSpecifier {
352  uint8_t encoding;
353  uint8_t type;
354};
355
356/*
357 * Indicates where the opcode modifier (if any) is to be found.  Extended
358 * opcodes with AddRegFrm have the opcode modifier in the ModR/M byte.
359 */
360
361#define MODIFIER_TYPES        \
362  ENUM_ENTRY(MODIFIER_NONE)   \
363  ENUM_ENTRY(MODIFIER_OPCODE) \
364  ENUM_ENTRY(MODIFIER_MODRM)
365
366#define ENUM_ENTRY(n) n,
367typedef enum {
368  MODIFIER_TYPES
369  MODIFIER_max
370} ModifierType;
371#undef ENUM_ENTRY
372
373#define X86_MAX_OPERANDS 5
374
375/*
376 * The specification for how to extract and interpret a full instruction and
377 * its operands.
378 */
379struct InstructionSpecifier {
380  uint8_t modifierType;
381  uint8_t modifierBase;
382
383  /* The macro below must be defined wherever this file is included. */
384  INSTRUCTION_SPECIFIER_FIELDS
385};
386
387/*
388 * Decoding mode for the Intel disassembler.  16-bit, 32-bit, and 64-bit mode
389 * are supported, and represent real mode, IA-32e, and IA-32e in 64-bit mode,
390 * respectively.
391 */
392typedef enum {
393  MODE_16BIT,
394  MODE_32BIT,
395  MODE_64BIT
396} DisassemblerMode;
397
398#endif
399