//===-- X86DisassemblerDecoderInternal.h - Disassembler decoder -*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file is part of the X86 Disassembler.
// It contains the public interface of the instruction decoder.
// Documentation for the disassembler can be found in X86Disassembler.h.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_LIB_TARGET_X86_DISASSEMBLER_X86DISASSEMBLERDECODER_H
#define LLVM_LIB_TARGET_X86_DISASSEMBLER_X86DISASSEMBLERDECODER_H
#include "X86DisassemblerDecoderCommon.h"
#include "llvm/ADT/ArrayRef.h"
namespace llvm {
namespace X86Disassembler {
// Accessor functions for various fields of an Intel instruction
#define modFromModRM(modRM) (((modRM) & 0xc0) >> 6)
#define regFromModRM(modRM) (((modRM) & 0x38) >> 3)
#define rmFromModRM(modRM) ((modRM) & 0x7)
#define scaleFromSIB(sib) (((sib) & 0xc0) >> 6)
#define indexFromSIB(sib) (((sib) & 0x38) >> 3)
#define baseFromSIB(sib) ((sib) & 0x7)
#define wFromREX(rex) (((rex) & 0x8) >> 3)
#define rFromREX(rex) (((rex) & 0x4) >> 2)
#define xFromREX(rex) (((rex) & 0x2) >> 1)
#define bFromREX(rex) ((rex) & 0x1)
#define rFromEVEX2of4(evex) (((~(evex)) & 0x80) >> 7)
#define xFromEVEX2of4(evex) (((~(evex)) & 0x40) >> 6)
#define bFromEVEX2of4(evex) (((~(evex)) & 0x20) >> 5)
#define r2FromEVEX2of4(evex) (((~(evex)) & 0x10) >> 4)
#define mmFromEVEX2of4(evex) ((evex) & 0x3)
#define wFromEVEX3of4(evex) (((evex) & 0x80) >> 7)
#define vvvvFromEVEX3of4(evex) (((~(evex)) & 0x78) >> 3)
#define ppFromEVEX3of4(evex) ((evex) & 0x3)
#define zFromEVEX4of4(evex) (((evex) & 0x80) >> 7)
#define l2FromEVEX4of4(evex) (((evex) & 0x40) >> 6)
#define lFromEVEX4of4(evex) (((evex) & 0x20) >> 5)
#define bFromEVEX4of4(evex) (((evex) & 0x10) >> 4)
#define v2FromEVEX4of4(evex) (((~evex) & 0x8) >> 3)
#define aaaFromEVEX4of4(evex) ((evex) & 0x7)
#define rFromVEX2of3(vex) (((~(vex)) & 0x80) >> 7)
#define xFromVEX2of3(vex) (((~(vex)) & 0x40) >> 6)
#define bFromVEX2of3(vex) (((~(vex)) & 0x20) >> 5)
#define mmmmmFromVEX2of3(vex) ((vex) & 0x1f)
#define wFromVEX3of3(vex) (((vex) & 0x80) >> 7)
#define vvvvFromVEX3of3(vex) (((~(vex)) & 0x78) >> 3)
#define lFromVEX3of3(vex) (((vex) & 0x4) >> 2)
#define ppFromVEX3of3(vex) ((vex) & 0x3)
#define rFromVEX2of2(vex) (((~(vex)) & 0x80) >> 7)
#define vvvvFromVEX2of2(vex) (((~(vex)) & 0x78) >> 3)
#define lFromVEX2of2(vex) (((vex) & 0x4) >> 2)
#define ppFromVEX2of2(vex) ((vex) & 0x3)
#define rFromXOP2of3(xop) (((~(xop)) & 0x80) >> 7)
#define xFromXOP2of3(xop) (((~(xop)) & 0x40) >> 6)
#define bFromXOP2of3(xop) (((~(xop)) & 0x20) >> 5)
#define mmmmmFromXOP2of3(xop) ((xop) & 0x1f)
#define wFromXOP3of3(xop) (((xop) & 0x80) >> 7)
#define vvvvFromXOP3of3(vex) (((~(vex)) & 0x78) >> 3)
#define lFromXOP3of3(xop) (((xop) & 0x4) >> 2)
#define ppFromXOP3of3(xop) ((xop) & 0x3)
// These enums represent Intel registers for use by the decoder.
#define REGS_8BIT \
ENTRY(AL) \
ENTRY(CL) \
ENTRY(DL) \
ENTRY(BL) \
ENTRY(AH) \
ENTRY(CH) \
ENTRY(DH) \
ENTRY(BH) \
ENTRY(R8B) \
ENTRY(R9B) \
ENTRY(R10B) \
ENTRY(R11B) \
ENTRY(R12B) \
ENTRY(R13B) \
ENTRY(R14B) \
ENTRY(R15B) \
ENTRY(SPL) \
ENTRY(BPL) \
ENTRY(SIL) \
ENTRY(DIL)
#define EA_BASES_16BIT \
ENTRY(BX_SI) \
ENTRY(BX_DI) \
ENTRY(BP_SI) \
ENTRY(BP_DI) \
ENTRY(SI) \
ENTRY(DI) \
ENTRY(BP) \
ENTRY(BX) \
ENTRY(R8W) \
ENTRY(R9W) \
ENTRY(R10W) \
ENTRY(R11W) \
ENTRY(R12W) \
ENTRY(R13W) \
ENTRY(R14W) \
ENTRY(R15W)
#define REGS_16BIT \
ENTRY(AX) \
ENTRY(CX) \
ENTRY(DX) \
ENTRY(BX) \
ENTRY(SP) \
ENTRY(BP) \
ENTRY(SI) \
ENTRY(DI) \
ENTRY(R8W) \
ENTRY(R9W) \
ENTRY(R10W) \
ENTRY(R11W) \
ENTRY(R12W) \
ENTRY(R13W) \
ENTRY(R14W) \
ENTRY(R15W)
#define EA_BASES_32BIT \
ENTRY(EAX) \
ENTRY(ECX) \
ENTRY(EDX) \
ENTRY(EBX) \
ENTRY(sib) \
ENTRY(EBP) \
ENTRY(ESI) \
ENTRY(EDI) \
ENTRY(R8D) \
ENTRY(R9D) \
ENTRY(R10D) \
ENTRY(R11D) \
ENTRY(R12D) \
ENTRY(R13D) \
ENTRY(R14D) \
ENTRY(R15D)
#define REGS_32BIT \
ENTRY(EAX) \
ENTRY(ECX) \
ENTRY(EDX) \
ENTRY(EBX) \
ENTRY(ESP) \
ENTRY(EBP) \
ENTRY(ESI) \
ENTRY(EDI) \
ENTRY(R8D) \
ENTRY(R9D) \
ENTRY(R10D) \
ENTRY(R11D) \
ENTRY(R12D) \
ENTRY(R13D) \
ENTRY(R14D) \
ENTRY(R15D)
#define EA_BASES_64BIT \
ENTRY(RAX) \
ENTRY(RCX) \
ENTRY(RDX) \
ENTRY(RBX) \
ENTRY(sib64) \
ENTRY(RBP) \
ENTRY(RSI) \
ENTRY(RDI) \
ENTRY(R8) \
ENTRY(R9) \
ENTRY(R10) \
ENTRY(R11) \
ENTRY(R12) \
ENTRY(R13) \
ENTRY(R14) \
ENTRY(R15)
#define REGS_64BIT \
ENTRY(RAX) \
ENTRY(RCX) \
ENTRY(RDX) \
ENTRY(RBX) \
ENTRY(RSP) \
ENTRY(RBP) \
ENTRY(RSI) \
ENTRY(RDI) \
ENTRY(R8) \
ENTRY(R9) \
ENTRY(R10) \
ENTRY(R11) \
ENTRY(R12) \
ENTRY(R13) \
ENTRY(R14) \
ENTRY(R15)
#define REGS_MMX \
ENTRY(MM0) \
ENTRY(MM1) \
ENTRY(MM2) \
ENTRY(MM3) \
ENTRY(MM4) \
ENTRY(MM5) \
ENTRY(MM6) \
ENTRY(MM7)
#define REGS_XMM \
ENTRY(XMM0) \
ENTRY(XMM1) \
ENTRY(XMM2) \
ENTRY(XMM3) \
ENTRY(XMM4) \
ENTRY(XMM5) \
ENTRY(XMM6) \
ENTRY(XMM7) \
ENTRY(XMM8) \
ENTRY(XMM9) \
ENTRY(XMM10) \
ENTRY(XMM11) \
ENTRY(XMM12) \
ENTRY(XMM13) \
ENTRY(XMM14) \
ENTRY(XMM15) \
ENTRY(XMM16) \
ENTRY(XMM17) \
ENTRY(XMM18) \
ENTRY(XMM19) \
ENTRY(XMM20) \
ENTRY(XMM21) \
ENTRY(XMM22) \
ENTRY(XMM23) \
ENTRY(XMM24) \
ENTRY(XMM25) \
ENTRY(XMM26) \
ENTRY(XMM27) \
ENTRY(XMM28) \
ENTRY(XMM29) \
ENTRY(XMM30) \
ENTRY(XMM31)
#define REGS_YMM \
ENTRY(YMM0) \
ENTRY(YMM1) \
ENTRY(YMM2) \
ENTRY(YMM3) \
ENTRY(YMM4) \
ENTRY(YMM5) \
ENTRY(YMM6) \
ENTRY(YMM7) \
ENTRY(YMM8) \
ENTRY(YMM9) \
ENTRY(YMM10) \
ENTRY(YMM11) \
ENTRY(YMM12) \
ENTRY(YMM13) \
ENTRY(YMM14) \
ENTRY(YMM15) \
ENTRY(YMM16) \
ENTRY(YMM17) \
ENTRY(YMM18) \
ENTRY(YMM19) \
ENTRY(YMM20) \
ENTRY(YMM21) \
ENTRY(YMM22) \
ENTRY(YMM23) \
ENTRY(YMM24) \
ENTRY(YMM25) \
ENTRY(YMM26) \
ENTRY(YMM27) \
ENTRY(YMM28) \
ENTRY(YMM29) \
ENTRY(YMM30) \
ENTRY(YMM31)
#define REGS_ZMM \
ENTRY(ZMM0) \
ENTRY(ZMM1) \
ENTRY(ZMM2) \
ENTRY(ZMM3) \
ENTRY(ZMM4) \
ENTRY(ZMM5) \
ENTRY(ZMM6) \
ENTRY(ZMM7) \
ENTRY(ZMM8) \
ENTRY(ZMM9) \
ENTRY(ZMM10) \
ENTRY(ZMM11) \
ENTRY(ZMM12) \
ENTRY(ZMM13) \
ENTRY(ZMM14) \
ENTRY(ZMM15) \
ENTRY(ZMM16) \
ENTRY(ZMM17) \
ENTRY(ZMM18) \
ENTRY(ZMM19) \
ENTRY(ZMM20) \
ENTRY(ZMM21) \
ENTRY(ZMM22) \
ENTRY(ZMM23) \
ENTRY(ZMM24) \
ENTRY(ZMM25) \
ENTRY(ZMM26) \
ENTRY(ZMM27) \
ENTRY(ZMM28) \
ENTRY(ZMM29) \
ENTRY(ZMM30) \
ENTRY(ZMM31)
#define REGS_MASKS \
ENTRY(K0) \
ENTRY(K1) \
ENTRY(K2) \
ENTRY(K3) \
ENTRY(K4) \
ENTRY(K5) \
ENTRY(K6) \
ENTRY(K7)
#define REGS_SEGMENT \
ENTRY(ES) \
ENTRY(CS) \
ENTRY(SS) \
ENTRY(DS) \
ENTRY(FS) \
ENTRY(GS)
#define REGS_DEBUG \
ENTRY(DR0) \
ENTRY(DR1) \
ENTRY(DR2) \
ENTRY(DR3) \
ENTRY(DR4) \
ENTRY(DR5) \
ENTRY(DR6) \
ENTRY(DR7) \
ENTRY(DR8) \
ENTRY(DR9) \
ENTRY(DR10) \
ENTRY(DR11) \
ENTRY(DR12) \
ENTRY(DR13) \
ENTRY(DR14) \
ENTRY(DR15)
#define REGS_CONTROL \
ENTRY(CR0) \
ENTRY(CR1) \
ENTRY(CR2) \
ENTRY(CR3) \
ENTRY(CR4) \
ENTRY(CR5) \
ENTRY(CR6) \
ENTRY(CR7) \
ENTRY(CR8) \
ENTRY(CR9) \
ENTRY(CR10) \
ENTRY(CR11) \
ENTRY(CR12) \
ENTRY(CR13) \
ENTRY(CR14) \
ENTRY(CR15)
#define ALL_EA_BASES \
EA_BASES_16BIT \
EA_BASES_32BIT \
EA_BASES_64BIT
#define ALL_SIB_BASES \
REGS_32BIT \
REGS_64BIT
#define ALL_REGS \
REGS_8BIT \
REGS_16BIT \
REGS_32BIT \
REGS_64BIT \
REGS_MMX \
REGS_XMM \
REGS_YMM \
REGS_ZMM \
REGS_MASKS \
REGS_SEGMENT \
REGS_DEBUG \
REGS_CONTROL \
ENTRY(RIP)
/// \brief All possible values of the base field for effective-address
/// computations, a.k.a. the Mod and R/M fields of the ModR/M byte.
/// We distinguish between bases (EA_BASE_*) and registers that just happen
/// to be referred to when Mod == 0b11 (EA_REG_*).
enum EABase {
EA_BASE_NONE,
#define ENTRY(x) EA_BASE_##x,
ALL_EA_BASES
#undef ENTRY
#define ENTRY(x) EA_REG_##x,
ALL_REGS
#undef ENTRY
EA_max
};
/// \brief All possible values of the SIB index field.
/// borrows entries from ALL_EA_BASES with the special case that
/// sib is synonymous with NONE.
/// Vector SIB: index can be XMM or YMM.
enum SIBIndex {
SIB_INDEX_NONE,
#define ENTRY(x) SIB_INDEX_##x,
ALL_EA_BASES
REGS_XMM
REGS_YMM
REGS_ZMM
#undef ENTRY
SIB_INDEX_max
};
/// \brief All possible values of the SIB base field.
enum SIBBase {
SIB_BASE_NONE,
#define ENTRY(x) SIB_BASE_##x,
ALL_SIB_BASES
#undef ENTRY
SIB_BASE_max
};
/// \brief Possible displacement types for effective-address computations.
typedef enum {
EA_DISP_NONE,
EA_DISP_8,
EA_DISP_16,
EA_DISP_32
} EADisplacement;
/// \brief All possible values of the reg field in the ModR/M byte.
enum Reg {
#define ENTRY(x) MODRM_REG_##x,
ALL_REGS
#undef ENTRY
MODRM_REG_max
};
/// \brief All possible segment overrides.
enum SegmentOverride {
SEG_OVERRIDE_NONE,
SEG_OVERRIDE_CS,
SEG_OVERRIDE_SS,
SEG_OVERRIDE_DS,
SEG_OVERRIDE_ES,
SEG_OVERRIDE_FS,
SEG_OVERRIDE_GS,
SEG_OVERRIDE_max
};
/// \brief Possible values for the VEX.m-mmmm field
enum VEXLeadingOpcodeByte {
VEX_LOB_0F = 0x1,
VEX_LOB_0F38 = 0x2,
VEX_LOB_0F3A = 0x3
};
enum XOPMapSelect {
XOP_MAP_SELECT_8 = 0x8,
XOP_MAP_SELECT_9 = 0x9,
XOP_MAP_SELECT_A = 0xA
};
/// \brief Possible values for the VEX.pp/EVEX.pp field
enum VEXPrefixCode {
VEX_PREFIX_NONE = 0x0,
VEX_PREFIX_66 = 0x1,
VEX_PREFIX_F3 = 0x2,
VEX_PREFIX_F2 = 0x3
};
enum VectorExtensionType {
TYPE_NO_VEX_XOP = 0x0,
TYPE_VEX_2B = 0x1,
TYPE_VEX_3B = 0x2,
TYPE_EVEX = 0x3,
TYPE_XOP = 0x4
};
/// \brief Type for the byte reader that the consumer must provide to
/// the decoder. Reads a single byte from the instruction's address space.
/// \param arg A baton that the consumer can associate with any internal
/// state that it needs.
/// \param byte A pointer to a single byte in memory that should be set to
/// contain the value at address.
/// \param address The address in the instruction's address space that should
/// be read from.
/// \return -1 if the byte cannot be read for any reason; 0 otherwise.
typedef int (*byteReader_t)(const void *arg, uint8_t *byte, uint64_t address);
/// \brief Type for the logging function that the consumer can provide to
/// get debugging output from the decoder.
/// \param arg A baton that the consumer can associate with any internal
/// state that it needs.
/// \param log A string that contains the message. Will be reused after
/// the logger returns.
typedef void (*dlog_t)(void *arg, const char *log);
/// The specification for how to extract and interpret a full instruction and
/// its operands.
struct InstructionSpecifier {
uint16_t operands;
};
/// The x86 internal instruction, which is produced by the decoder.
struct InternalInstruction {
// Reader interface (C)
byteReader_t reader;
// Opaque value passed to the reader
const void* readerArg;
// The address of the next byte to read via the reader
uint64_t readerCursor;
// Logger interface (C)
dlog_t dlog;
// Opaque value passed to the logger
void* dlogArg;
// General instruction information
// The mode to disassemble for (64-bit, protected, real)
DisassemblerMode mode;
// The start of the instruction, usable with the reader
uint64_t startLocation;
// The length of the instruction, in bytes
size_t length;
// Prefix state
// 1 if the prefix byte corresponding to the entry is present; 0 if not
uint8_t prefixPresent[0x100];
// contains the location (for use with the reader) of the prefix byte
uint64_t prefixLocations[0x100];
// The value of the vector extension prefix(EVEX/VEX/XOP), if present
uint8_t vectorExtensionPrefix[4];
// The type of the vector extension prefix
VectorExtensionType vectorExtensionType;
// The value of the REX prefix, if present
uint8_t rexPrefix;
// The location where a mandatory prefix would have to be (i.e., right before
// the opcode, or right before the REX prefix if one is present).
uint64_t necessaryPrefixLocation;
// The segment override type
SegmentOverride segmentOverride;
// 1 if the prefix byte, 0xf2 or 0xf3 is xacquire or xrelease
bool xAcquireRelease;
// Sizes of various critical pieces of data, in bytes
uint8_t registerSize;
uint8_t addressSize;
uint8_t displacementSize;
uint8_t immediateSize;
// Offsets from the start of the instruction to the pieces of data, which is
// needed to find relocation entries for adding symbolic operands.
uint8_t displacementOffset;
uint8_t immediateOffset;
// opcode state
// The last byte of the opcode, not counting any ModR/M extension
uint8_t opcode;
// decode state
// The type of opcode, used for indexing into the array of decode tables
OpcodeType opcodeType;
// The instruction ID, extracted from the decode table
uint16_t instructionID;
// The specifier for the instruction, from the instruction info table
const InstructionSpecifier *spec;
// state for additional bytes, consumed during operand decode. Pattern:
// consumed___ indicates that the byte was already consumed and does not
// need to be consumed again.
// The VEX.vvvv field, which contains a third register operand for some AVX
// instructions.
Reg vvvv;
// The writemask for AVX-512 instructions which is contained in EVEX.aaa
Reg writemask;
// The ModR/M byte, which contains most register operands and some portion of
// all memory operands.
bool consumedModRM;
uint8_t modRM;
// The SIB byte, used for more complex 32- or 64-bit memory operands
bool consumedSIB;
uint8_t sib;
// The displacement, used for memory operands
bool consumedDisplacement;
int32_t displacement;
// Immediates. There can be two in some cases
uint8_t numImmediatesConsumed;
uint8_t numImmediatesTranslated;
uint64_t immediates[2];
// A register or immediate operand encoded into the opcode
Reg opcodeRegister;
// Portions of the ModR/M byte
// These fields determine the allowable values for the ModR/M fields, which
// depend on operand and address widths.
EABase eaBaseBase;
EABase eaRegBase;
Reg regBase;
// The Mod and R/M fields can encode a base for an effective address, or a
// register. These are separated into two fields here.
EABase eaBase;
EADisplacement eaDisplacement;
// The reg field always encodes a register
Reg reg;
// SIB state
SIBIndex sibIndex;
uint8_t sibScale;
SIBBase sibBase;
ArrayRef<OperandSpecifier> operands;
};
/// \brief Decode one instruction and store the decoding results in
/// a buffer provided by the consumer.
/// \param insn The buffer to store the instruction in. Allocated by the
/// consumer.
/// \param reader The byteReader_t for the bytes to be read.
/// \param readerArg An argument to pass to the reader for storing context
/// specific to the consumer. May be NULL.
/// \param logger The dlog_t to be used in printing status messages from the
/// disassembler. May be NULL.
/// \param loggerArg An argument to pass to the logger for storing context
/// specific to the logger. May be NULL.
/// \param startLoc The address (in the reader's address space) of the first
/// byte in the instruction.
/// \param mode The mode (16-bit, 32-bit, 64-bit) to decode in.
/// \return Nonzero if there was an error during decode, 0 otherwise.
int decodeInstruction(InternalInstruction *insn,
byteReader_t reader,
const void *readerArg,
dlog_t logger,
void *loggerArg,
const void *miiArg,
uint64_t startLoc,
DisassemblerMode mode);
/// \brief Print a message to debugs()
/// \param file The name of the file printing the debug message.
/// \param line The line number that printed the debug message.
/// \param s The message to print.
void Debug(const char *file, unsigned line, const char *s);
const char *GetInstrName(unsigned Opcode, const void *mii);
} // namespace X86Disassembler
} // namespace llvm
#endif