llvm-6502/lib/Target/AArch64/Disassembler/AArch64Disassembler.cpp
Tim Northover 19254c49a8 Remove cyclic dependency in AArch64 libraries
This moves the bit twiddling and string fiddling functions required by other
parts of the backend into a separate library. Previously they resided in
AArch64Desc, which created a circular dependency between various components.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@174369 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-05 13:24:47 +00:00

778 lines
29 KiB
C++

//===- AArch64Disassembler.cpp - Disassembler for AArch64/Thumb ISA -------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "arm-disassembler"
#include "AArch64.h"
#include "AArch64RegisterInfo.h"
#include "AArch64Subtarget.h"
#include "Utils/AArch64BaseInfo.h"
#include "llvm/MC/MCInst.h"
#include "llvm/MC/MCInstrDesc.h"
#include "llvm/MC/MCExpr.h"
#include "llvm/MC/MCContext.h"
#include "llvm/MC/MCDisassembler.h"
#include "llvm/MC/MCFixedLenDisassembler.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/MemoryObject.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/TargetRegistry.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
typedef MCDisassembler::DecodeStatus DecodeStatus;
namespace {
/// AArch64 disassembler for all AArch64 platforms.
class AArch64Disassembler : public MCDisassembler {
const MCRegisterInfo *RegInfo;
public:
/// Initializes the disassembler.
///
AArch64Disassembler(const MCSubtargetInfo &STI, const MCRegisterInfo *Info)
: MCDisassembler(STI), RegInfo(Info) {
}
~AArch64Disassembler() {
}
/// See MCDisassembler.
DecodeStatus getInstruction(MCInst &instr,
uint64_t &size,
const MemoryObject &region,
uint64_t address,
raw_ostream &vStream,
raw_ostream &cStream) const;
const MCRegisterInfo *getRegInfo() const { return RegInfo; }
};
}
// Forward-declarations used in the auto-generated files.
static DecodeStatus DecodeGPR64RegisterClass(llvm::MCInst &Inst, unsigned RegNo,
uint64_t Address, const void *Decoder);
static DecodeStatus
DecodeGPR64xspRegisterClass(llvm::MCInst &Inst, unsigned RegNo,
uint64_t Address, const void *Decoder);
static DecodeStatus DecodeGPR32RegisterClass(llvm::MCInst &Inst, unsigned RegNo,
uint64_t Address, const void *Decoder);
static DecodeStatus
DecodeGPR32wspRegisterClass(llvm::MCInst &Inst, unsigned RegNo,
uint64_t Address, const void *Decoder);
static DecodeStatus DecodeFPR8RegisterClass(llvm::MCInst &Inst, unsigned RegNo,
uint64_t Address, const void *Decoder);
static DecodeStatus DecodeFPR16RegisterClass(llvm::MCInst &Inst, unsigned RegNo,
uint64_t Address, const void *Decoder);
static DecodeStatus DecodeFPR32RegisterClass(llvm::MCInst &Inst, unsigned RegNo,
uint64_t Address, const void *Decoder);
static DecodeStatus DecodeFPR64RegisterClass(llvm::MCInst &Inst, unsigned RegNo,
uint64_t Address, const void *Decoder);
static DecodeStatus DecodeFPR128RegisterClass(llvm::MCInst &Inst, unsigned RegNo,
uint64_t Address, const void *Decoder);
static DecodeStatus DecodeVPR128RegisterClass(llvm::MCInst &Inst, unsigned RegNo,
uint64_t Address, const void *Decoder);
static DecodeStatus DecodeAddrRegExtendOperand(llvm::MCInst &Inst,
unsigned OptionHiS,
uint64_t Address,
const void *Decoder);
static DecodeStatus DecodeBitfield32ImmOperand(llvm::MCInst &Inst,
unsigned Imm6Bits,
uint64_t Address,
const void *Decoder);
static DecodeStatus DecodeCVT32FixedPosOperand(llvm::MCInst &Inst,
unsigned Imm6Bits,
uint64_t Address,
const void *Decoder);
template<int RegWidth>
static DecodeStatus DecodeMoveWideImmOperand(llvm::MCInst &Inst,
unsigned FullImm,
uint64_t Address,
const void *Decoder);
template<int RegWidth>
static DecodeStatus DecodeLogicalImmOperand(llvm::MCInst &Inst,
unsigned Bits,
uint64_t Address,
const void *Decoder);
static DecodeStatus DecodeRegExtendOperand(llvm::MCInst &Inst,
unsigned ShiftAmount,
uint64_t Address,
const void *Decoder);
static DecodeStatus Decode32BitShiftOperand(llvm::MCInst &Inst,
unsigned ShiftAmount,
uint64_t Address,
const void *Decoder);
static DecodeStatus DecodeBitfieldInstruction(llvm::MCInst &Inst, unsigned Insn,
uint64_t Address,
const void *Decoder);
static DecodeStatus DecodeFMOVLaneInstruction(llvm::MCInst &Inst, unsigned Insn,
uint64_t Address,
const void *Decoder);
static DecodeStatus DecodeLDSTPairInstruction(llvm::MCInst &Inst,
unsigned Insn,
uint64_t Address,
const void *Decoder);
static DecodeStatus DecodeLoadPairExclusiveInstruction(llvm::MCInst &Inst,
unsigned Val,
uint64_t Address,
const void *Decoder);
template<typename SomeNamedImmMapper>
static DecodeStatus DecodeNamedImmOperand(llvm::MCInst &Inst,
unsigned Val,
uint64_t Address,
const void *Decoder);
static DecodeStatus DecodeSysRegOperand(const A64SysReg::SysRegMapper &InstMapper,
llvm::MCInst &Inst,
unsigned Val,
uint64_t Address,
const void *Decoder);
static DecodeStatus DecodeMRSOperand(llvm::MCInst &Inst,
unsigned Val,
uint64_t Address,
const void *Decoder);
static DecodeStatus DecodeMSROperand(llvm::MCInst &Inst,
unsigned Val,
uint64_t Address,
const void *Decoder);
static DecodeStatus DecodeSingleIndexedInstruction(llvm::MCInst &Inst,
unsigned Val,
uint64_t Address,
const void *Decoder);
static bool Check(DecodeStatus &Out, DecodeStatus In);
#include "AArch64GenDisassemblerTables.inc"
#include "AArch64GenInstrInfo.inc"
static bool Check(DecodeStatus &Out, DecodeStatus In) {
switch (In) {
case MCDisassembler::Success:
// Out stays the same.
return true;
case MCDisassembler::SoftFail:
Out = In;
return true;
case MCDisassembler::Fail:
Out = In;
return false;
}
llvm_unreachable("Invalid DecodeStatus!");
}
DecodeStatus AArch64Disassembler::getInstruction(MCInst &MI, uint64_t &Size,
const MemoryObject &Region,
uint64_t Address,
raw_ostream &os,
raw_ostream &cs) const {
CommentStream = &cs;
uint8_t bytes[4];
// We want to read exactly 4 bytes of data.
if (Region.readBytes(Address, 4, (uint8_t*)bytes, NULL) == -1) {
Size = 0;
return MCDisassembler::Fail;
}
// Encoded as a small-endian 32-bit word in the stream.
uint32_t insn = (bytes[3] << 24) |
(bytes[2] << 16) |
(bytes[1] << 8) |
(bytes[0] << 0);
// Calling the auto-generated decoder function.
DecodeStatus result = decodeInstruction(DecoderTableA6432, MI, insn, Address,
this, STI);
if (result != MCDisassembler::Fail) {
Size = 4;
return result;
}
MI.clear();
Size = 0;
return MCDisassembler::Fail;
}
static unsigned getReg(const void *D, unsigned RC, unsigned RegNo) {
const AArch64Disassembler *Dis = static_cast<const AArch64Disassembler*>(D);
return Dis->getRegInfo()->getRegClass(RC).getRegister(RegNo);
}
static DecodeStatus DecodeGPR64RegisterClass(llvm::MCInst &Inst, unsigned RegNo,
uint64_t Address, const void *Decoder) {
if (RegNo > 31)
return MCDisassembler::Fail;
uint16_t Register = getReg(Decoder, AArch64::GPR64RegClassID, RegNo);
Inst.addOperand(MCOperand::CreateReg(Register));
return MCDisassembler::Success;
}
static DecodeStatus
DecodeGPR64xspRegisterClass(llvm::MCInst &Inst, unsigned RegNo,
uint64_t Address, const void *Decoder) {
if (RegNo > 31)
return MCDisassembler::Fail;
uint16_t Register = getReg(Decoder, AArch64::GPR64xspRegClassID, RegNo);
Inst.addOperand(MCOperand::CreateReg(Register));
return MCDisassembler::Success;
}
static DecodeStatus DecodeGPR32RegisterClass(llvm::MCInst &Inst, unsigned RegNo,
uint64_t Address, const void *Decoder) {
if (RegNo > 31)
return MCDisassembler::Fail;
uint16_t Register = getReg(Decoder, AArch64::GPR32RegClassID, RegNo);
Inst.addOperand(MCOperand::CreateReg(Register));
return MCDisassembler::Success;
}
static DecodeStatus
DecodeGPR32wspRegisterClass(llvm::MCInst &Inst, unsigned RegNo,
uint64_t Address, const void *Decoder) {
if (RegNo > 31)
return MCDisassembler::Fail;
uint16_t Register = getReg(Decoder, AArch64::GPR32wspRegClassID, RegNo);
Inst.addOperand(MCOperand::CreateReg(Register));
return MCDisassembler::Success;
}
static DecodeStatus
DecodeFPR8RegisterClass(llvm::MCInst &Inst, unsigned RegNo,
uint64_t Address, const void *Decoder) {
if (RegNo > 31)
return MCDisassembler::Fail;
uint16_t Register = getReg(Decoder, AArch64::FPR8RegClassID, RegNo);
Inst.addOperand(MCOperand::CreateReg(Register));
return MCDisassembler::Success;
}
static DecodeStatus
DecodeFPR16RegisterClass(llvm::MCInst &Inst, unsigned RegNo,
uint64_t Address, const void *Decoder) {
if (RegNo > 31)
return MCDisassembler::Fail;
uint16_t Register = getReg(Decoder, AArch64::FPR16RegClassID, RegNo);
Inst.addOperand(MCOperand::CreateReg(Register));
return MCDisassembler::Success;
}
static DecodeStatus
DecodeFPR32RegisterClass(llvm::MCInst &Inst, unsigned RegNo,
uint64_t Address, const void *Decoder) {
if (RegNo > 31)
return MCDisassembler::Fail;
uint16_t Register = getReg(Decoder, AArch64::FPR32RegClassID, RegNo);
Inst.addOperand(MCOperand::CreateReg(Register));
return MCDisassembler::Success;
}
static DecodeStatus
DecodeFPR64RegisterClass(llvm::MCInst &Inst, unsigned RegNo,
uint64_t Address, const void *Decoder) {
if (RegNo > 31)
return MCDisassembler::Fail;
uint16_t Register = getReg(Decoder, AArch64::FPR64RegClassID, RegNo);
Inst.addOperand(MCOperand::CreateReg(Register));
return MCDisassembler::Success;
}
static DecodeStatus
DecodeFPR128RegisterClass(llvm::MCInst &Inst, unsigned RegNo,
uint64_t Address, const void *Decoder) {
if (RegNo > 31)
return MCDisassembler::Fail;
uint16_t Register = getReg(Decoder, AArch64::FPR128RegClassID, RegNo);
Inst.addOperand(MCOperand::CreateReg(Register));
return MCDisassembler::Success;
}
static DecodeStatus
DecodeVPR128RegisterClass(llvm::MCInst &Inst, unsigned RegNo,
uint64_t Address, const void *Decoder) {
if (RegNo > 31)
return MCDisassembler::Fail;
uint16_t Register = getReg(Decoder, AArch64::VPR128RegClassID, RegNo);
Inst.addOperand(MCOperand::CreateReg(Register));
return MCDisassembler::Success;
}
static DecodeStatus DecodeAddrRegExtendOperand(llvm::MCInst &Inst,
unsigned OptionHiS,
uint64_t Address,
const void *Decoder) {
// Option{1} must be 1. OptionHiS is made up of {Option{2}, Option{1},
// S}. Hence we want to check bit 1.
if (!(OptionHiS & 2))
return MCDisassembler::Fail;
Inst.addOperand(MCOperand::CreateImm(OptionHiS));
return MCDisassembler::Success;
}
static DecodeStatus DecodeBitfield32ImmOperand(llvm::MCInst &Inst,
unsigned Imm6Bits,
uint64_t Address,
const void *Decoder) {
// In the 32-bit variant, bit 6 must be zero. I.e. the immediate must be
// between 0 and 31.
if (Imm6Bits > 31)
return MCDisassembler::Fail;
Inst.addOperand(MCOperand::CreateImm(Imm6Bits));
return MCDisassembler::Success;
}
static DecodeStatus DecodeCVT32FixedPosOperand(llvm::MCInst &Inst,
unsigned Imm6Bits,
uint64_t Address,
const void *Decoder) {
// 1 <= Imm <= 32. Encoded as 64 - Imm so: 63 >= Encoded >= 32.
if (Imm6Bits < 32)
return MCDisassembler::Fail;
Inst.addOperand(MCOperand::CreateImm(Imm6Bits));
return MCDisassembler::Success;
}
template<int RegWidth>
static DecodeStatus DecodeMoveWideImmOperand(llvm::MCInst &Inst,
unsigned FullImm,
uint64_t Address,
const void *Decoder) {
unsigned Imm16 = FullImm & 0xffff;
unsigned Shift = FullImm >> 16;
if (RegWidth == 32 && Shift > 1) return MCDisassembler::Fail;
Inst.addOperand(MCOperand::CreateImm(Imm16));
Inst.addOperand(MCOperand::CreateImm(Shift));
return MCDisassembler::Success;
}
template<int RegWidth>
static DecodeStatus DecodeLogicalImmOperand(llvm::MCInst &Inst,
unsigned Bits,
uint64_t Address,
const void *Decoder) {
uint64_t Imm;
if (!A64Imms::isLogicalImmBits(RegWidth, Bits, Imm))
return MCDisassembler::Fail;
Inst.addOperand(MCOperand::CreateImm(Bits));
return MCDisassembler::Success;
}
static DecodeStatus DecodeRegExtendOperand(llvm::MCInst &Inst,
unsigned ShiftAmount,
uint64_t Address,
const void *Decoder) {
// Only values 0-4 are valid for this 3-bit field
if (ShiftAmount > 4)
return MCDisassembler::Fail;
Inst.addOperand(MCOperand::CreateImm(ShiftAmount));
return MCDisassembler::Success;
}
static DecodeStatus Decode32BitShiftOperand(llvm::MCInst &Inst,
unsigned ShiftAmount,
uint64_t Address,
const void *Decoder) {
// Only values below 32 are valid for a 32-bit register
if (ShiftAmount > 31)
return MCDisassembler::Fail;
Inst.addOperand(MCOperand::CreateImm(ShiftAmount));
return MCDisassembler::Success;
}
static DecodeStatus DecodeBitfieldInstruction(llvm::MCInst &Inst, unsigned Insn,
uint64_t Address,
const void *Decoder) {
unsigned Rd = fieldFromInstruction(Insn, 0, 5);
unsigned Rn = fieldFromInstruction(Insn, 5, 5);
unsigned ImmS = fieldFromInstruction(Insn, 10, 6);
unsigned ImmR = fieldFromInstruction(Insn, 16, 6);
unsigned SF = fieldFromInstruction(Insn, 31, 1);
// Undef for 0b11 just in case it occurs. Don't want the compiler to optimise
// out assertions that it thinks should never be hit.
enum OpcTypes { SBFM = 0, BFM, UBFM, Undef } Opc;
Opc = (OpcTypes)fieldFromInstruction(Insn, 29, 2);
if (!SF) {
// ImmR and ImmS must be between 0 and 31 for 32-bit instructions.
if (ImmR > 31 || ImmS > 31)
return MCDisassembler::Fail;
}
if (SF) {
DecodeGPR64RegisterClass(Inst, Rd, Address, Decoder);
// BFM MCInsts use Rd as a source too.
if (Opc == BFM) DecodeGPR64RegisterClass(Inst, Rd, Address, Decoder);
DecodeGPR64RegisterClass(Inst, Rn, Address, Decoder);
} else {
DecodeGPR32RegisterClass(Inst, Rd, Address, Decoder);
// BFM MCInsts use Rd as a source too.
if (Opc == BFM) DecodeGPR32RegisterClass(Inst, Rd, Address, Decoder);
DecodeGPR32RegisterClass(Inst, Rn, Address, Decoder);
}
// ASR and LSR have more specific patterns so they won't get here:
assert(!(ImmS == 31 && !SF && Opc != BFM) && "shift should have used auto decode");
assert(!(ImmS == 63 && SF && Opc != BFM) && "shift should have used auto decode");
// Extension instructions similarly:
if (Opc == SBFM && ImmR == 0) {
assert((ImmS != 7 && ImmS != 15) && "extension got here");
assert((ImmS != 31 || SF == 0) && "extension got here");
} else if (Opc == UBFM && ImmR == 0) {
assert((SF != 0 || (ImmS != 7 && ImmS != 15)) && "extension got here");
}
if (Opc == UBFM) {
// It might be a LSL instruction, which actually takes the shift amount
// itself as an MCInst operand.
if (SF && (ImmS + 1) % 64 == ImmR) {
Inst.setOpcode(AArch64::LSLxxi);
Inst.addOperand(MCOperand::CreateImm(63 - ImmS));
return MCDisassembler::Success;
} else if (!SF && (ImmS + 1) % 32 == ImmR) {
Inst.setOpcode(AArch64::LSLwwi);
Inst.addOperand(MCOperand::CreateImm(31 - ImmS));
return MCDisassembler::Success;
}
}
// Otherwise it's definitely either an extract or an insert depending on which
// of ImmR or ImmS is larger.
unsigned ExtractOp, InsertOp;
switch (Opc) {
default: llvm_unreachable("unexpected instruction trying to decode bitfield");
case SBFM:
ExtractOp = SF ? AArch64::SBFXxxii : AArch64::SBFXwwii;
InsertOp = SF ? AArch64::SBFIZxxii : AArch64::SBFIZwwii;
break;
case BFM:
ExtractOp = SF ? AArch64::BFXILxxii : AArch64::BFXILwwii;
InsertOp = SF ? AArch64::BFIxxii : AArch64::BFIwwii;
break;
case UBFM:
ExtractOp = SF ? AArch64::UBFXxxii : AArch64::UBFXwwii;
InsertOp = SF ? AArch64::UBFIZxxii : AArch64::UBFIZwwii;
break;
}
// Otherwise it's a boring insert or extract
Inst.addOperand(MCOperand::CreateImm(ImmR));
Inst.addOperand(MCOperand::CreateImm(ImmS));
if (ImmS < ImmR)
Inst.setOpcode(InsertOp);
else
Inst.setOpcode(ExtractOp);
return MCDisassembler::Success;
}
static DecodeStatus DecodeFMOVLaneInstruction(llvm::MCInst &Inst, unsigned Insn,
uint64_t Address,
const void *Decoder) {
// This decoder exists to add the dummy Lane operand to the MCInst, which must
// be 1 in assembly but has no other real manifestation.
unsigned Rd = fieldFromInstruction(Insn, 0, 5);
unsigned Rn = fieldFromInstruction(Insn, 5, 5);
unsigned IsToVec = fieldFromInstruction(Insn, 16, 1);
if (IsToVec) {
DecodeVPR128RegisterClass(Inst, Rd, Address, Decoder);
DecodeGPR64RegisterClass(Inst, Rn, Address, Decoder);
} else {
DecodeGPR64RegisterClass(Inst, Rd, Address, Decoder);
DecodeVPR128RegisterClass(Inst, Rn, Address, Decoder);
}
// Add the lane
Inst.addOperand(MCOperand::CreateImm(1));
return MCDisassembler::Success;
}
static DecodeStatus DecodeLDSTPairInstruction(llvm::MCInst &Inst,
unsigned Insn,
uint64_t Address,
const void *Decoder) {
DecodeStatus Result = MCDisassembler::Success;
unsigned Rt = fieldFromInstruction(Insn, 0, 5);
unsigned Rn = fieldFromInstruction(Insn, 5, 5);
unsigned Rt2 = fieldFromInstruction(Insn, 10, 5);
unsigned SImm7 = fieldFromInstruction(Insn, 15, 7);
unsigned L = fieldFromInstruction(Insn, 22, 1);
unsigned V = fieldFromInstruction(Insn, 26, 1);
unsigned Opc = fieldFromInstruction(Insn, 30, 2);
// Not an official name, but it turns out that bit 23 distinguishes indexed
// from non-indexed operations.
unsigned Indexed = fieldFromInstruction(Insn, 23, 1);
if (Indexed && L == 0) {
// The MCInst for an indexed store has an out operand and 4 ins:
// Rn_wb, Rt, Rt2, Rn, Imm
DecodeGPR64xspRegisterClass(Inst, Rn, Address, Decoder);
}
// You shouldn't load to the same register twice in an instruction...
if (L && Rt == Rt2)
Result = MCDisassembler::SoftFail;
// ... or do any operation that writes-back to a transfer register. But note
// that "stp xzr, xzr, [sp], #4" is fine because xzr and sp are different.
if (Indexed && V == 0 && Rn != 31 && (Rt == Rn || Rt2 == Rn))
Result = MCDisassembler::SoftFail;
// Exactly how we decode the MCInst's registers depends on the Opc and V
// fields of the instruction. These also obviously determine the size of the
// operation so we can fill in that information while we're at it.
if (V) {
// The instruction operates on the FP/SIMD registers
switch (Opc) {
default: return MCDisassembler::Fail;
case 0:
DecodeFPR32RegisterClass(Inst, Rt, Address, Decoder);
DecodeFPR32RegisterClass(Inst, Rt2, Address, Decoder);
break;
case 1:
DecodeFPR64RegisterClass(Inst, Rt, Address, Decoder);
DecodeFPR64RegisterClass(Inst, Rt2, Address, Decoder);
break;
case 2:
DecodeFPR128RegisterClass(Inst, Rt, Address, Decoder);
DecodeFPR128RegisterClass(Inst, Rt2, Address, Decoder);
break;
}
} else {
switch (Opc) {
default: return MCDisassembler::Fail;
case 0:
DecodeGPR32RegisterClass(Inst, Rt, Address, Decoder);
DecodeGPR32RegisterClass(Inst, Rt2, Address, Decoder);
break;
case 1:
assert(L && "unexpected \"store signed\" attempt");
DecodeGPR64RegisterClass(Inst, Rt, Address, Decoder);
DecodeGPR64RegisterClass(Inst, Rt2, Address, Decoder);
break;
case 2:
DecodeGPR64RegisterClass(Inst, Rt, Address, Decoder);
DecodeGPR64RegisterClass(Inst, Rt2, Address, Decoder);
break;
}
}
if (Indexed && L == 1) {
// The MCInst for an indexed load has 3 out operands and an 3 ins:
// Rt, Rt2, Rn_wb, Rt2, Rn, Imm
DecodeGPR64xspRegisterClass(Inst, Rn, Address, Decoder);
}
DecodeGPR64xspRegisterClass(Inst, Rn, Address, Decoder);
Inst.addOperand(MCOperand::CreateImm(SImm7));
return Result;
}
static DecodeStatus DecodeLoadPairExclusiveInstruction(llvm::MCInst &Inst,
uint32_t Val,
uint64_t Address,
const void *Decoder) {
unsigned Rt = fieldFromInstruction(Val, 0, 5);
unsigned Rn = fieldFromInstruction(Val, 5, 5);
unsigned Rt2 = fieldFromInstruction(Val, 10, 5);
unsigned MemSize = fieldFromInstruction(Val, 30, 2);
DecodeStatus S = MCDisassembler::Success;
if (Rt == Rt2) S = MCDisassembler::SoftFail;
switch (MemSize) {
case 2:
if (!Check(S, DecodeGPR32RegisterClass(Inst, Rt, Address, Decoder)))
return MCDisassembler::Fail;
if (!Check(S, DecodeGPR32RegisterClass(Inst, Rt2, Address, Decoder)))
return MCDisassembler::Fail;
break;
case 3:
if (!Check(S, DecodeGPR64RegisterClass(Inst, Rt, Address, Decoder)))
return MCDisassembler::Fail;
if (!Check(S, DecodeGPR64RegisterClass(Inst, Rt2, Address, Decoder)))
return MCDisassembler::Fail;
break;
default:
llvm_unreachable("Invalid MemSize in DecodeLoadPairExclusiveInstruction");
}
if (!Check(S, DecodeGPR64xspRegisterClass(Inst, Rn, Address, Decoder)))
return MCDisassembler::Fail;
return S;
}
template<typename SomeNamedImmMapper>
static DecodeStatus DecodeNamedImmOperand(llvm::MCInst &Inst,
unsigned Val,
uint64_t Address,
const void *Decoder) {
SomeNamedImmMapper Mapper;
bool ValidNamed;
Mapper.toString(Val, ValidNamed);
if (ValidNamed || Mapper.validImm(Val)) {
Inst.addOperand(MCOperand::CreateImm(Val));
return MCDisassembler::Success;
}
return MCDisassembler::Fail;
}
static DecodeStatus DecodeSysRegOperand(const A64SysReg::SysRegMapper &Mapper,
llvm::MCInst &Inst,
unsigned Val,
uint64_t Address,
const void *Decoder) {
bool ValidNamed;
Mapper.toString(Val, ValidNamed);
Inst.addOperand(MCOperand::CreateImm(Val));
return ValidNamed ? MCDisassembler::Success : MCDisassembler::Fail;
}
static DecodeStatus DecodeMRSOperand(llvm::MCInst &Inst,
unsigned Val,
uint64_t Address,
const void *Decoder) {
return DecodeSysRegOperand(A64SysReg::MRSMapper(), Inst, Val, Address,
Decoder);
}
static DecodeStatus DecodeMSROperand(llvm::MCInst &Inst,
unsigned Val,
uint64_t Address,
const void *Decoder) {
return DecodeSysRegOperand(A64SysReg::MSRMapper(), Inst, Val, Address,
Decoder);
}
static DecodeStatus DecodeSingleIndexedInstruction(llvm::MCInst &Inst,
unsigned Insn,
uint64_t Address,
const void *Decoder) {
unsigned Rt = fieldFromInstruction(Insn, 0, 5);
unsigned Rn = fieldFromInstruction(Insn, 5, 5);
unsigned Imm9 = fieldFromInstruction(Insn, 12, 9);
unsigned Opc = fieldFromInstruction(Insn, 22, 2);
unsigned V = fieldFromInstruction(Insn, 26, 1);
unsigned Size = fieldFromInstruction(Insn, 30, 2);
if (Opc == 0 || (V == 1 && Opc == 2)) {
// It's a store, the MCInst gets: Rn_wb, Rt, Rn, Imm
DecodeGPR64xspRegisterClass(Inst, Rn, Address, Decoder);
}
if (V == 0 && (Opc == 2 || Size == 3)) {
DecodeGPR64RegisterClass(Inst, Rt, Address, Decoder);
} else if (V == 0) {
DecodeGPR32RegisterClass(Inst, Rt, Address, Decoder);
} else if (V == 1 && (Opc & 2)) {
DecodeFPR128RegisterClass(Inst, Rt, Address, Decoder);
} else {
switch (Size) {
case 0:
DecodeFPR8RegisterClass(Inst, Rt, Address, Decoder);
break;
case 1:
DecodeFPR16RegisterClass(Inst, Rt, Address, Decoder);
break;
case 2:
DecodeFPR32RegisterClass(Inst, Rt, Address, Decoder);
break;
case 3:
DecodeFPR64RegisterClass(Inst, Rt, Address, Decoder);
break;
}
}
if (Opc != 0 && (V != 1 || Opc != 2)) {
// It's a load, the MCInst gets: Rt, Rn_wb, Rn, Imm
DecodeGPR64xspRegisterClass(Inst, Rn, Address, Decoder);
}
DecodeGPR64xspRegisterClass(Inst, Rn, Address, Decoder);
Inst.addOperand(MCOperand::CreateImm(Imm9));
// N.b. The official documentation says undpredictable if Rt == Rn, but this
// takes place at the architectural rather than encoding level:
//
// "STR xzr, [sp], #4" is perfectly valid.
if (V == 0 && Rt == Rn && Rn != 31)
return MCDisassembler::SoftFail;
else
return MCDisassembler::Success;
}
static MCDisassembler *createAArch64Disassembler(const Target &T,
const MCSubtargetInfo &STI) {
return new AArch64Disassembler(STI, T.createMCRegInfo(""));
}
extern "C" void LLVMInitializeAArch64Disassembler() {
TargetRegistry::RegisterMCDisassembler(TheAArch64Target,
createAArch64Disassembler);
}