//===- ARMDisassemblerCore.cpp - ARM disassembler helpers -------*- 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 ARM Disassembler.
// It contains code to represent the core concepts of Builder and DisassembleFP
// to solve the problem of disassembling an ARM instr.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "arm-disassembler"
#include "ARMDisassemblerCore.h"
#include "ARMAddressingModes.h"
#include "ARMMCExpr.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
//#define DEBUG(X) do { X; } while (0)
/// ARMGenInstrInfo.inc - ARMGenInstrInfo.inc contains the static const
/// MCInstrDesc ARMInsts[] definition and the MCOperandInfo[]'s describing the
/// operand info for each ARMInsts[i].
///
/// Together with an instruction's encoding format, we can take advantage of the
/// NumOperands and the OpInfo fields of the target instruction description in
/// the quest to build out the MCOperand list for an MCInst.
///
/// The general guideline is that with a known format, the number of dst and src
/// operands are well-known. The dst is built first, followed by the src
/// operand(s). The operands not yet used at this point are for the Implicit
/// Uses and Defs by this instr. For the Uses part, the pred:$p operand is
/// defined with two components:
///
/// def pred { // Operand PredicateOperand
/// ValueType Type = OtherVT;
/// string PrintMethod = "printPredicateOperand";
/// string AsmOperandLowerMethod = ?;
/// dag MIOperandInfo = (ops i32imm, CCR);
/// AsmOperandClass ParserMatchClass = ImmAsmOperand;
/// dag DefaultOps = (ops (i32 14), (i32 zero_reg));
/// }
///
/// which is manifested by the MCOperandInfo[] of:
///
/// { 0, 0|(1<<MCOI::Predicate), 0 },
/// { ARM::CCRRegClassID, 0|(1<<MCOI::Predicate), 0 }
///
/// So the first predicate MCOperand corresponds to the immediate part of the
/// ARM condition field (Inst{31-28}), and the second predicate MCOperand
/// corresponds to a register kind of ARM::CPSR.
///
/// For the Defs part, in the simple case of only cc_out:$s, we have:
///
/// def cc_out { // Operand OptionalDefOperand
/// ValueType Type = OtherVT;
/// string PrintMethod = "printSBitModifierOperand";
/// string AsmOperandLowerMethod = ?;
/// dag MIOperandInfo = (ops CCR);
/// AsmOperandClass ParserMatchClass = ImmAsmOperand;
/// dag DefaultOps = (ops (i32 zero_reg));
/// }
///
/// which is manifested by the one MCOperandInfo of:
///
/// { ARM::CCRRegClassID, 0|(1<<MCOI::OptionalDef), 0 }
///
namespace llvm {
extern MCInstrDesc ARMInsts[];
}
using namespace llvm;
const char *ARMUtils::OpcodeName(unsigned Opcode) {
return ARMInsts[Opcode].Name;
}
// Return the register enum Based on RegClass and the raw register number.
// FIXME: Auto-gened?
static unsigned
getRegisterEnum(BO B, unsigned RegClassID, unsigned RawRegister) {
if (RegClassID == ARM::rGPRRegClassID) {
// Check for The register numbers 13 and 15 that are not permitted for many
// Thumb register specifiers.
if (RawRegister == 13 || RawRegister == 15) {
B->SetErr(-1);
return 0;
}
// For this purpose, we can treat rGPR as if it were GPR.
RegClassID = ARM::GPRRegClassID;
}
// See also decodeNEONRd(), decodeNEONRn(), decodeNEONRm().
// A7.3 register encoding
// Qd -> bit[12] == 0
// Qn -> bit[16] == 0
// Qm -> bit[0] == 0
//
// If one of these bits is 1, the instruction is UNDEFINED.
if (RegClassID == ARM::QPRRegClassID && slice(RawRegister, 0, 0) == 1) {
B->SetErr(-1);
return 0;
}
unsigned RegNum =
RegClassID == ARM::QPRRegClassID ? RawRegister >> 1 : RawRegister;
switch (RegNum) {
default:
break;
case 0:
switch (RegClassID) {
case ARM::GPRRegClassID: case ARM::tGPRRegClassID: return ARM::R0;
case ARM::DPRRegClassID: case ARM::DPR_8RegClassID:
case ARM::DPR_VFP2RegClassID:
return ARM::D0;
case ARM::QPRRegClassID: case ARM::QPR_8RegClassID:
case ARM::QPR_VFP2RegClassID:
return ARM::Q0;
case ARM::SPRRegClassID: case ARM::SPR_8RegClassID: return ARM::S0;
}
break;
case 1:
switch (RegClassID) {
case ARM::GPRRegClassID: case ARM::tGPRRegClassID: return ARM::R1;
case ARM::DPRRegClassID: case ARM::DPR_8RegClassID:
case ARM::DPR_VFP2RegClassID:
return ARM::D1;
case ARM::QPRRegClassID: case ARM::QPR_8RegClassID:
case ARM::QPR_VFP2RegClassID:
return ARM::Q1;
case ARM::SPRRegClassID: case ARM::SPR_8RegClassID: return ARM::S1;
}
break;
case 2:
switch (RegClassID) {
case ARM::GPRRegClassID: case ARM::tGPRRegClassID: return ARM::R2;
case ARM::DPRRegClassID: case ARM::DPR_8RegClassID:
case ARM::DPR_VFP2RegClassID:
return ARM::D2;
case ARM::QPRRegClassID: case ARM::QPR_8RegClassID:
case ARM::QPR_VFP2RegClassID:
return ARM::Q2;
case ARM::SPRRegClassID: case ARM::SPR_8RegClassID: return ARM::S2;
}
break;
case 3:
switch (RegClassID) {
case ARM::GPRRegClassID: case ARM::tGPRRegClassID: return ARM::R3;
case ARM::DPRRegClassID: case ARM::DPR_8RegClassID:
case ARM::DPR_VFP2RegClassID:
return ARM::D3;
case ARM::QPRRegClassID: case ARM::QPR_8RegClassID:
case ARM::QPR_VFP2RegClassID:
return ARM::Q3;
case ARM::SPRRegClassID: case ARM::SPR_8RegClassID: return ARM::S3;
}
break;
case 4:
switch (RegClassID) {
case ARM::GPRRegClassID: case ARM::tGPRRegClassID: return ARM::R4;
case ARM::DPRRegClassID: case ARM::DPR_8RegClassID:
case ARM::DPR_VFP2RegClassID:
return ARM::D4;
case ARM::QPRRegClassID: case ARM::QPR_VFP2RegClassID: return ARM::Q4;
case ARM::SPRRegClassID: case ARM::SPR_8RegClassID: return ARM::S4;
}
break;
case 5:
switch (RegClassID) {
case ARM::GPRRegClassID: case ARM::tGPRRegClassID: return ARM::R5;
case ARM::DPRRegClassID: case ARM::DPR_8RegClassID:
case ARM::DPR_VFP2RegClassID:
return ARM::D5;
case ARM::QPRRegClassID: case ARM::QPR_VFP2RegClassID: return ARM::Q5;
case ARM::SPRRegClassID: case ARM::SPR_8RegClassID: return ARM::S5;
}
break;
case 6:
switch (RegClassID) {
case ARM::GPRRegClassID: case ARM::tGPRRegClassID: return ARM::R6;
case ARM::DPRRegClassID: case ARM::DPR_8RegClassID:
case ARM::DPR_VFP2RegClassID:
return ARM::D6;
case ARM::QPRRegClassID: case ARM::QPR_VFP2RegClassID: return ARM::Q6;
case ARM::SPRRegClassID: case ARM::SPR_8RegClassID: return ARM::S6;
}
break;
case 7:
switch (RegClassID) {
case ARM::GPRRegClassID: case ARM::tGPRRegClassID: return ARM::R7;
case ARM::DPRRegClassID: case ARM::DPR_8RegClassID:
case ARM::DPR_VFP2RegClassID:
return ARM::D7;
case ARM::QPRRegClassID: case ARM::QPR_VFP2RegClassID: return ARM::Q7;
case ARM::SPRRegClassID: case ARM::SPR_8RegClassID: return ARM::S7;
}
break;
case 8:
switch (RegClassID) {
case ARM::GPRRegClassID: return ARM::R8;
case ARM::DPRRegClassID: case ARM::DPR_VFP2RegClassID: return ARM::D8;
case ARM::QPRRegClassID: return ARM::Q8;
case ARM::SPRRegClassID: case ARM::SPR_8RegClassID: return ARM::S8;
}
break;
case 9:
switch (RegClassID) {
case ARM::GPRRegClassID: return ARM::R9;
case ARM::DPRRegClassID: case ARM::DPR_VFP2RegClassID: return ARM::D9;
case ARM::QPRRegClassID: return ARM::Q9;
case ARM::SPRRegClassID: case ARM::SPR_8RegClassID: return ARM::S9;
}
break;
case 10:
switch (RegClassID) {
case ARM::GPRRegClassID: return ARM::R10;
case ARM::DPRRegClassID: case ARM::DPR_VFP2RegClassID: return ARM::D10;
case ARM::QPRRegClassID: return ARM::Q10;
case ARM::SPRRegClassID: case ARM::SPR_8RegClassID: return ARM::S10;
}
break;
case 11:
switch (RegClassID) {
case ARM::GPRRegClassID: return ARM::R11;
case ARM::DPRRegClassID: case ARM::DPR_VFP2RegClassID: return ARM::D11;
case ARM::QPRRegClassID: return ARM::Q11;
case ARM::SPRRegClassID: case ARM::SPR_8RegClassID: return ARM::S11;
}
break;
case 12:
switch (RegClassID) {
case ARM::GPRRegClassID: return ARM::R12;
case ARM::DPRRegClassID: case ARM::DPR_VFP2RegClassID: return ARM::D12;
case ARM::QPRRegClassID: return ARM::Q12;
case ARM::SPRRegClassID: case ARM::SPR_8RegClassID: return ARM::S12;
}
break;
case 13:
switch (RegClassID) {
case ARM::GPRRegClassID: return ARM::SP;
case ARM::DPRRegClassID: case ARM::DPR_VFP2RegClassID: return ARM::D13;
case ARM::QPRRegClassID: return ARM::Q13;
case ARM::SPRRegClassID: case ARM::SPR_8RegClassID: return ARM::S13;
}
break;
case 14:
switch (RegClassID) {
case ARM::GPRRegClassID: return ARM::LR;
case ARM::DPRRegClassID: case ARM::DPR_VFP2RegClassID: return ARM::D14;
case ARM::QPRRegClassID: return ARM::Q14;
case ARM::SPRRegClassID: case ARM::SPR_8RegClassID: return ARM::S14;
}
break;
case 15:
switch (RegClassID) {
case ARM::GPRRegClassID: return ARM::PC;
case ARM::DPRRegClassID: case ARM::DPR_VFP2RegClassID: return ARM::D15;
case ARM::QPRRegClassID: return ARM::Q15;
case ARM::SPRRegClassID: case ARM::SPR_8RegClassID: return ARM::S15;
}
break;
case 16:
switch (RegClassID) {
case ARM::DPRRegClassID: return ARM::D16;
case ARM::SPRRegClassID: return ARM::S16;
}
break;
case 17:
switch (RegClassID) {
case ARM::DPRRegClassID: return ARM::D17;
case ARM::SPRRegClassID: return ARM::S17;
}
break;
case 18:
switch (RegClassID) {
case ARM::DPRRegClassID: return ARM::D18;
case ARM::SPRRegClassID: return ARM::S18;
}
break;
case 19:
switch (RegClassID) {
case ARM::DPRRegClassID: return ARM::D19;
case ARM::SPRRegClassID: return ARM::S19;
}
break;
case 20:
switch (RegClassID) {
case ARM::DPRRegClassID: return ARM::D20;
case ARM::SPRRegClassID: return ARM::S20;
}
break;
case 21:
switch (RegClassID) {
case ARM::DPRRegClassID: return ARM::D21;
case ARM::SPRRegClassID: return ARM::S21;
}
break;
case 22:
switch (RegClassID) {
case ARM::DPRRegClassID: return ARM::D22;
case ARM::SPRRegClassID: return ARM::S22;
}
break;
case 23:
switch (RegClassID) {
case ARM::DPRRegClassID: return ARM::D23;
case ARM::SPRRegClassID: return ARM::S23;
}
break;
case 24:
switch (RegClassID) {
case ARM::DPRRegClassID: return ARM::D24;
case ARM::SPRRegClassID: return ARM::S24;
}
break;
case 25:
switch (RegClassID) {
case ARM::DPRRegClassID: return ARM::D25;
case ARM::SPRRegClassID: return ARM::S25;
}
break;
case 26:
switch (RegClassID) {
case ARM::DPRRegClassID: return ARM::D26;
case ARM::SPRRegClassID: return ARM::S26;
}
break;
case 27:
switch (RegClassID) {
case ARM::DPRRegClassID: return ARM::D27;
case ARM::SPRRegClassID: return ARM::S27;
}
break;
case 28:
switch (RegClassID) {
case ARM::DPRRegClassID: return ARM::D28;
case ARM::SPRRegClassID: return ARM::S28;
}
break;
case 29:
switch (RegClassID) {
case ARM::DPRRegClassID: return ARM::D29;
case ARM::SPRRegClassID: return ARM::S29;
}
break;
case 30:
switch (RegClassID) {
case ARM::DPRRegClassID: return ARM::D30;
case ARM::SPRRegClassID: return ARM::S30;
}
break;
case 31:
switch (RegClassID) {
case ARM::DPRRegClassID: return ARM::D31;
case ARM::SPRRegClassID: return ARM::S31;
}
break;
}
DEBUG(errs() << "Invalid (RegClassID, RawRegister) combination\n");
// Encoding error. Mark the builder with error code != 0.
B->SetErr(-1);
return 0;
}
///////////////////////////////
// //
// Utility Functions //
// //
///////////////////////////////
// Extract/Decode Rd: Inst{15-12}.
static inline unsigned decodeRd(uint32_t insn) {
return (insn >> ARMII::RegRdShift) & ARMII::GPRRegMask;
}
// Extract/Decode Rn: Inst{19-16}.
static inline unsigned decodeRn(uint32_t insn) {
return (insn >> ARMII::RegRnShift) & ARMII::GPRRegMask;
}
// Extract/Decode Rm: Inst{3-0}.
static inline unsigned decodeRm(uint32_t insn) {
return (insn & ARMII::GPRRegMask);
}
// Extract/Decode Rs: Inst{11-8}.
static inline unsigned decodeRs(uint32_t insn) {
return (insn >> ARMII::RegRsShift) & ARMII::GPRRegMask;
}
static inline unsigned getCondField(uint32_t insn) {
return (insn >> ARMII::CondShift);
}
static inline unsigned getIBit(uint32_t insn) {
return (insn >> ARMII::I_BitShift) & 1;
}
static inline unsigned getAM3IBit(uint32_t insn) {
return (insn >> ARMII::AM3_I_BitShift) & 1;
}
static inline unsigned getPBit(uint32_t insn) {
return (insn >> ARMII::P_BitShift) & 1;
}
static inline unsigned getUBit(uint32_t insn) {
return (insn >> ARMII::U_BitShift) & 1;
}
static inline unsigned getPUBits(uint32_t insn) {
return (insn >> ARMII::U_BitShift) & 3;
}
static inline unsigned getSBit(uint32_t insn) {
return (insn >> ARMII::S_BitShift) & 1;
}
static inline unsigned getWBit(uint32_t insn) {
return (insn >> ARMII::W_BitShift) & 1;
}
static inline unsigned getDBit(uint32_t insn) {
return (insn >> ARMII::D_BitShift) & 1;
}
static inline unsigned getNBit(uint32_t insn) {
return (insn >> ARMII::N_BitShift) & 1;
}
static inline unsigned getMBit(uint32_t insn) {
return (insn >> ARMII::M_BitShift) & 1;
}
// See A8.4 Shifts applied to a register.
// A8.4.2 Register controlled shifts.
//
// getShiftOpcForBits - getShiftOpcForBits translates from the ARM encoding bits
// into llvm enums for shift opcode. The API clients should pass in the value
// encoded with two bits, so the assert stays to signal a wrong API usage.
//
// A8-12: DecodeRegShift()
static inline ARM_AM::ShiftOpc getShiftOpcForBits(unsigned bits) {
switch (bits) {
default: assert(0 && "No such value"); return ARM_AM::no_shift;
case 0: return ARM_AM::lsl;
case 1: return ARM_AM::lsr;
case 2: return ARM_AM::asr;
case 3: return ARM_AM::ror;
}
}
// See A8.4 Shifts applied to a register.
// A8.4.1 Constant shifts.
//
// getImmShiftSE - getImmShiftSE translates from the raw ShiftOpc and raw Imm5
// encodings into the intended ShiftOpc and shift amount.
//
// A8-11: DecodeImmShift()
static inline void getImmShiftSE(ARM_AM::ShiftOpc &ShOp, unsigned &ShImm) {
if (ShImm != 0)
return;
switch (ShOp) {
case ARM_AM::no_shift:
case ARM_AM::rrx:
break;
case ARM_AM::lsl:
ShOp = ARM_AM::no_shift;
break;
case ARM_AM::lsr:
case ARM_AM::asr:
ShImm = 32;
break;
case ARM_AM::ror:
ShOp = ARM_AM::rrx;
break;
}
}
// getAMSubModeForBits - getAMSubModeForBits translates from the ARM encoding
// bits Inst{24-23} (P(24) and U(23)) into llvm enums for AMSubMode. The API
// clients should pass in the value encoded with two bits, so the assert stays
// to signal a wrong API usage.
static inline ARM_AM::AMSubMode getAMSubModeForBits(unsigned bits) {
switch (bits) {
default: assert(0 && "No such value"); return ARM_AM::bad_am_submode;
case 1: return ARM_AM::ia; // P=0 U=1
case 3: return ARM_AM::ib; // P=1 U=1
case 0: return ARM_AM::da; // P=0 U=0
case 2: return ARM_AM::db; // P=1 U=0
}
}
////////////////////////////////////////////
// //
// Disassemble function definitions //
// //
////////////////////////////////////////////
/// There is a separate Disassemble*Frm function entry for disassembly of an ARM
/// instr into a list of MCOperands in the appropriate order, with possible dst,
/// followed by possible src(s).
///
/// The processing of the predicate, and the 'S' modifier bit, if MI modifies
/// the CPSR, is factored into ARMBasicMCBuilder's method named
/// TryPredicateAndSBitModifier.
static bool DisassemblePseudo(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO) {
assert(0 && "Unexpected pseudo instruction!");
return false;
}
// A8.6.94 MLA
// if d == 15 || n == 15 || m == 15 || a == 15 then UNPREDICTABLE;
//
// A8.6.105 MUL
// if d == 15 || n == 15 || m == 15 then UNPREDICTABLE;
//
// A8.6.246 UMULL
// if dLo == 15 || dHi == 15 || n == 15 || m == 15 then UNPREDICTABLE;
// if dHi == dLo then UNPREDICTABLE;
static bool BadRegsMulFrm(unsigned Opcode, uint32_t insn) {
unsigned R19_16 = slice(insn, 19, 16);
unsigned R15_12 = slice(insn, 15, 12);
unsigned R11_8 = slice(insn, 11, 8);
unsigned R3_0 = slice(insn, 3, 0);
switch (Opcode) {
default:
// Did we miss an opcode?
DEBUG(errs() << "BadRegsMulFrm: unexpected opcode!");
return false;
case ARM::MLA: case ARM::MLS: case ARM::SMLABB: case ARM::SMLABT:
case ARM::SMLATB: case ARM::SMLATT: case ARM::SMLAWB: case ARM::SMLAWT:
case ARM::SMMLA: case ARM::SMMLAR: case ARM::SMMLS: case ARM::SMMLSR:
case ARM::USADA8:
if (R19_16 == 15 || R15_12 == 15 || R11_8 == 15 || R3_0 == 15)
return true;
return false;
case ARM::MUL: case ARM::SMMUL: case ARM::SMMULR:
case ARM::SMULBB: case ARM::SMULBT: case ARM::SMULTB: case ARM::SMULTT:
case ARM::SMULWB: case ARM::SMULWT: case ARM::SMUAD: case ARM::SMUADX:
// A8.6.167 SMLAD & A8.6.172 SMLSD
case ARM::SMLAD: case ARM::SMLADX: case ARM::SMLSD: case ARM::SMLSDX:
case ARM::USAD8:
if (R19_16 == 15 || R11_8 == 15 || R3_0 == 15)
return true;
return false;
case ARM::SMLAL: case ARM::SMULL: case ARM::UMAAL: case ARM::UMLAL:
case ARM::UMULL:
case ARM::SMLALBB: case ARM::SMLALBT: case ARM::SMLALTB: case ARM::SMLALTT:
case ARM::SMLALD: case ARM::SMLALDX: case ARM::SMLSLD: case ARM::SMLSLDX:
if (R19_16 == 15 || R15_12 == 15 || R11_8 == 15 || R3_0 == 15)
return true;
if (R19_16 == R15_12)
return true;
return false;;
}
}
// Multiply Instructions.
// MLA, MLS, SMLABB, SMLABT, SMLATB, SMLATT, SMLAWB, SMLAWT, SMMLA, SMMLAR,
// SMMLS, SMMLAR, SMLAD, SMLADX, SMLSD, SMLSDX, and USADA8 (for convenience):
// Rd{19-16} Rn{3-0} Rm{11-8} Ra{15-12}
// But note that register checking for {SMLAD, SMLADX, SMLSD, SMLSDX} is
// only for {d, n, m}.
//
// MUL, SMMUL, SMMULR, SMULBB, SMULBT, SMULTB, SMULTT, SMULWB, SMULWT, SMUAD,
// SMUADX, and USAD8 (for convenience):
// Rd{19-16} Rn{3-0} Rm{11-8}
//
// SMLAL, SMULL, UMAAL, UMLAL, UMULL, SMLALBB, SMLALBT, SMLALTB, SMLALTT,
// SMLALD, SMLADLX, SMLSLD, SMLSLDX:
// RdLo{15-12} RdHi{19-16} Rn{3-0} Rm{11-8}
//
// The mapping of the multiply registers to the "regular" ARM registers, where
// there are convenience decoder functions, is:
//
// Inst{15-12} => Rd
// Inst{19-16} => Rn
// Inst{3-0} => Rm
// Inst{11-8} => Rs
static bool DisassembleMulFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
const MCInstrDesc &MCID = ARMInsts[Opcode];
unsigned short NumDefs = MCID.getNumDefs();
const MCOperandInfo *OpInfo = MCID.OpInfo;
unsigned &OpIdx = NumOpsAdded;
OpIdx = 0;
assert(NumDefs > 0 && "NumDefs should be greater than 0 for MulFrm");
assert(NumOps >= 3
&& OpInfo[0].RegClass == ARM::GPRRegClassID
&& OpInfo[1].RegClass == ARM::GPRRegClassID
&& OpInfo[2].RegClass == ARM::GPRRegClassID
&& "Expect three register operands");
// Sanity check for the register encodings.
if (BadRegsMulFrm(Opcode, insn))
return false;
// Instructions with two destination registers have RdLo{15-12} first.
if (NumDefs == 2) {
assert(NumOps >= 4 && OpInfo[3].RegClass == ARM::GPRRegClassID &&
"Expect 4th register operand");
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRd(insn))));
++OpIdx;
}
// The destination register: RdHi{19-16} or Rd{19-16}.
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRn(insn))));
// The two src regsiters: Rn{3-0}, then Rm{11-8}.
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRm(insn))));
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRs(insn))));
OpIdx += 3;
// Many multiply instructions (e.g., MLA) have three src registers.
// The third register operand is Ra{15-12}.
if (OpIdx < NumOps && OpInfo[OpIdx].RegClass == ARM::GPRRegClassID) {
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRd(insn))));
++OpIdx;
}
return true;
}
// Helper routines for disassembly of coprocessor instructions.
static bool LdStCopOpcode(unsigned Opcode) {
if ((Opcode >= ARM::LDC2L_OFFSET && Opcode <= ARM::LDC_PRE) ||
(Opcode >= ARM::STC2L_OFFSET && Opcode <= ARM::STC_PRE))
return true;
return false;
}
static bool CoprocessorOpcode(unsigned Opcode) {
if (LdStCopOpcode(Opcode))
return true;
switch (Opcode) {
default:
return false;
case ARM::CDP: case ARM::CDP2:
case ARM::MCR: case ARM::MCR2: case ARM::MRC: case ARM::MRC2:
case ARM::MCRR: case ARM::MCRR2: case ARM::MRRC: case ARM::MRRC2:
return true;
}
}
static inline unsigned GetCoprocessor(uint32_t insn) {
return slice(insn, 11, 8);
}
static inline unsigned GetCopOpc1(uint32_t insn, bool CDP) {
return CDP ? slice(insn, 23, 20) : slice(insn, 23, 21);
}
static inline unsigned GetCopOpc2(uint32_t insn) {
return slice(insn, 7, 5);
}
static inline unsigned GetCopOpc(uint32_t insn) {
return slice(insn, 7, 4);
}
// Most of the operands are in immediate forms, except Rd and Rn, which are ARM
// core registers.
//
// CDP, CDP2: cop opc1 CRd CRn CRm opc2
//
// MCR, MCR2, MRC, MRC2: cop opc1 Rd CRn CRm opc2
//
// MCRR, MCRR2, MRRC, MRRc2: cop opc Rd Rn CRm
//
// LDC_OFFSET, LDC_PRE, LDC_POST: cop CRd Rn R0 [+/-]imm8:00
// and friends
// STC_OFFSET, STC_PRE, STC_POST: cop CRd Rn R0 [+/-]imm8:00
// and friends
// <-- addrmode2 -->
//
// LDC_OPTION: cop CRd Rn imm8
// and friends
// STC_OPTION: cop CRd Rn imm8
// and friends
//
static bool DisassembleCoprocessor(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
assert(NumOps >= 4 && "Num of operands >= 4 for coprocessor instr");
unsigned &OpIdx = NumOpsAdded;
// A8.6.92
// if coproc == '101x' then SEE "Advanced SIMD and VFP"
// But since the special instructions have more explicit encoding bits
// specified, if coproc == 10 or 11, we should reject it as invalid.
unsigned coproc = GetCoprocessor(insn);
if ((Opcode == ARM::MCR || Opcode == ARM::MCRR ||
Opcode == ARM::MRC || Opcode == ARM::MRRC) &&
(coproc == 10 || coproc == 11)) {
DEBUG(errs() << "Encoding error: coproc == 10 or 11 for MCR[R]/MR[R]C\n");
return false;
}
bool OneCopOpc = (Opcode == ARM::MCRR || Opcode == ARM::MCRR2 ||
Opcode == ARM::MRRC || Opcode == ARM::MRRC2);
// CDP/CDP2 has no GPR operand; the opc1 operand is also wider (Inst{23-20}).
bool NoGPR = (Opcode == ARM::CDP || Opcode == ARM::CDP2);
bool LdStCop = LdStCopOpcode(Opcode);
bool RtOut = (Opcode == ARM::MRC || Opcode == ARM::MRC2);
OpIdx = 0;
if (RtOut) {
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRd(insn))));
++OpIdx;
}
MI.addOperand(MCOperand::CreateImm(coproc));
++OpIdx;
if (LdStCop) {
// Unindex if P:W = 0b00 --> _OPTION variant
unsigned PW = getPBit(insn) << 1 | getWBit(insn);
MI.addOperand(MCOperand::CreateImm(decodeRd(insn)));
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRn(insn))));
OpIdx += 2;
if (PW) {
MI.addOperand(MCOperand::CreateReg(0));
ARM_AM::AddrOpc AddrOpcode = getUBit(insn) ? ARM_AM::add : ARM_AM::sub;
const MCInstrDesc &MCID = ARMInsts[Opcode];
unsigned IndexMode =
(MCID.TSFlags & ARMII::IndexModeMask) >> ARMII::IndexModeShift;
unsigned Offset = ARM_AM::getAM2Opc(AddrOpcode, slice(insn, 7, 0) << 2,
ARM_AM::no_shift, IndexMode);
MI.addOperand(MCOperand::CreateImm(Offset));
OpIdx += 2;
} else {
MI.addOperand(MCOperand::CreateImm(slice(insn, 7, 0)));
++OpIdx;
}
} else {
MI.addOperand(MCOperand::CreateImm(OneCopOpc ? GetCopOpc(insn)
: GetCopOpc1(insn, NoGPR)));
++OpIdx;
if (!RtOut) {
MI.addOperand(NoGPR ? MCOperand::CreateImm(decodeRd(insn))
: MCOperand::CreateReg(
getRegisterEnum(B, ARM::GPRRegClassID,
decodeRd(insn))));
++OpIdx;
}
MI.addOperand(OneCopOpc ? MCOperand::CreateReg(
getRegisterEnum(B, ARM::GPRRegClassID,
decodeRn(insn)))
: MCOperand::CreateImm(decodeRn(insn)));
MI.addOperand(MCOperand::CreateImm(decodeRm(insn)));
OpIdx += 2;
if (!OneCopOpc) {
MI.addOperand(MCOperand::CreateImm(GetCopOpc2(insn)));
++OpIdx;
}
}
return true;
}
// Branch Instructions.
// BL: SignExtend(Imm24:'00', 32)
// Bcc, BL_pred: SignExtend(Imm24:'00', 32) Pred0 Pred1
// SMC: ZeroExtend(imm4, 32)
// SVC: ZeroExtend(Imm24, 32)
//
// Various coprocessor instructions are assigned BrFrm arbitrarily.
// Delegates to DisassembleCoprocessor() helper function.
//
// MRS/MRSsys: Rd
// MSR/MSRsys: Rm mask=Inst{19-16}
// BXJ: Rm
// MSRi/MSRsysi: so_imm
// SRSW/SRS: ldstm_mode:$amode mode_imm
// RFEW/RFE: ldstm_mode:$amode Rn
static bool DisassembleBrFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
if (CoprocessorOpcode(Opcode))
return DisassembleCoprocessor(MI, Opcode, insn, NumOps, NumOpsAdded, B);
const MCOperandInfo *OpInfo = ARMInsts[Opcode].OpInfo;
if (!OpInfo) return false;
// MRS and MRSsys take one GPR reg Rd.
if (Opcode == ARM::MRS || Opcode == ARM::MRSsys) {
assert(NumOps >= 1 && OpInfo[0].RegClass == ARM::GPRRegClassID &&
"Reg operand expected");
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRd(insn))));
NumOpsAdded = 1;
return true;
}
// BXJ takes one GPR reg Rm.
if (Opcode == ARM::BXJ) {
assert(NumOps >= 1 && OpInfo[0].RegClass == ARM::GPRRegClassID &&
"Reg operand expected");
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRm(insn))));
NumOpsAdded = 1;
return true;
}
// MSR take a mask, followed by one GPR reg Rm. The mask contains the R Bit in
// bit 4, and the special register fields in bits 3-0.
if (Opcode == ARM::MSR) {
assert(NumOps >= 1 && OpInfo[1].RegClass == ARM::GPRRegClassID &&
"Reg operand expected");
MI.addOperand(MCOperand::CreateImm(slice(insn, 22, 22) << 4 /* R Bit */ |
slice(insn, 19, 16) /* Special Reg */ ));
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRm(insn))));
NumOpsAdded = 2;
return true;
}
// MSRi take a mask, followed by one so_imm operand. The mask contains the
// R Bit in bit 4, and the special register fields in bits 3-0.
if (Opcode == ARM::MSRi) {
// A5.2.11 MSR (immediate), and hints & B6.1.6 MSR (immediate)
// The hints instructions have more specific encodings, so if mask == 0,
// we should reject this as an invalid instruction.
if (slice(insn, 19, 16) == 0)
return false;
MI.addOperand(MCOperand::CreateImm(slice(insn, 22, 22) << 4 /* R Bit */ |
slice(insn, 19, 16) /* Special Reg */ ));
// SOImm is 4-bit rotate amount in bits 11-8 with 8-bit imm in bits 7-0.
// A5.2.4 Rotate amount is twice the numeric value of Inst{11-8}.
// See also ARMAddressingModes.h: getSOImmValImm() and getSOImmValRot().
unsigned Rot = (insn >> ARMII::SoRotImmShift) & 0xF;
unsigned Imm = insn & 0xFF;
MI.addOperand(MCOperand::CreateImm(ARM_AM::rotr32(Imm, 2*Rot)));
NumOpsAdded = 2;
return true;
}
if (Opcode == ARM::SRSW || Opcode == ARM::SRS ||
Opcode == ARM::RFEW || Opcode == ARM::RFE) {
ARM_AM::AMSubMode SubMode = getAMSubModeForBits(getPUBits(insn));
MI.addOperand(MCOperand::CreateImm(ARM_AM::getAM4ModeImm(SubMode)));
if (Opcode == ARM::SRSW || Opcode == ARM::SRS)
MI.addOperand(MCOperand::CreateImm(slice(insn, 4, 0)));
else
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRn(insn))));
NumOpsAdded = 3;
return true;
}
assert((Opcode == ARM::Bcc || Opcode == ARM::BL || Opcode == ARM::BL_pred
|| Opcode == ARM::SMC || Opcode == ARM::SVC) &&
"Unexpected Opcode");
assert(NumOps >= 1 && OpInfo[0].RegClass < 0 && "Imm operand expected");
int Imm32 = 0;
if (Opcode == ARM::SMC) {
// ZeroExtend(imm4, 32) where imm24 = Inst{3-0}.
Imm32 = slice(insn, 3, 0);
} else if (Opcode == ARM::SVC) {
// ZeroExtend(imm24, 32) where imm24 = Inst{23-0}.
Imm32 = slice(insn, 23, 0);
} else {
// SignExtend(imm24:'00', 32) where imm24 = Inst{23-0}.
unsigned Imm26 = slice(insn, 23, 0) << 2;
//Imm32 = signextend<signed int, 26>(Imm26);
Imm32 = SignExtend32<26>(Imm26);
}
MI.addOperand(MCOperand::CreateImm(Imm32));
NumOpsAdded = 1;
return true;
}
// Misc. Branch Instructions.
// BX_RET, MOVPCLR
// BLX, BLX_pred, BX, BX_pred
// BLXi
static bool DisassembleBrMiscFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
const MCOperandInfo *OpInfo = ARMInsts[Opcode].OpInfo;
if (!OpInfo) return false;
unsigned &OpIdx = NumOpsAdded;
OpIdx = 0;
// BX_RET and MOVPCLR have only two predicate operands; do an early return.
if (Opcode == ARM::BX_RET || Opcode == ARM::MOVPCLR)
return true;
// BLX and BX take one GPR reg.
if (Opcode == ARM::BLX || Opcode == ARM::BLX_pred ||
Opcode == ARM::BX || Opcode == ARM::BX_pred) {
assert(NumOps >= 1 && OpInfo[OpIdx].RegClass == ARM::GPRRegClassID &&
"Reg operand expected");
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRm(insn))));
OpIdx = 1;
return true;
}
// BLXi takes imm32 (the PC offset).
if (Opcode == ARM::BLXi) {
assert(NumOps >= 1 && OpInfo[0].RegClass < 0 && "Imm operand expected");
// SignExtend(imm24:H:'0', 32) where imm24 = Inst{23-0} and H = Inst{24}.
unsigned Imm26 = slice(insn, 23, 0) << 2 | slice(insn, 24, 24) << 1;
int Imm32 = SignExtend32<26>(Imm26);
MI.addOperand(MCOperand::CreateImm(Imm32));
OpIdx = 1;
return true;
}
return false;
}
static inline bool getBFCInvMask(uint32_t insn, uint32_t &mask) {
uint32_t lsb = slice(insn, 11, 7);
uint32_t msb = slice(insn, 20, 16);
uint32_t Val = 0;
if (msb < lsb) {
DEBUG(errs() << "Encoding error: msb < lsb\n");
return false;
}
for (uint32_t i = lsb; i <= msb; ++i)
Val |= (1 << i);
mask = ~Val;
return true;
}
// Standard data-processing instructions allow PC as a register specifier,
// but we should reject other DPFrm instructions with PC as registers.
static bool BadRegsDPFrm(unsigned Opcode, uint32_t insn) {
switch (Opcode) {
default:
// Did we miss an opcode?
if (decodeRd(insn) == 15 || decodeRn(insn) == 15 || decodeRm(insn) == 15) {
DEBUG(errs() << "DPFrm with bad reg specifier(s)\n");
return true;
}
case ARM::ADCrr: case ARM::ADDSrr: case ARM::ADDrr: case ARM::ANDrr:
case ARM::BICrr: case ARM::CMNzrr: case ARM::CMPrr: case ARM::EORrr:
case ARM::ORRrr: case ARM::RSBrr: case ARM::RSCrr: case ARM::SBCrr:
case ARM::SUBSrr: case ARM::SUBrr: case ARM::TEQrr: case ARM::TSTrr:
return false;
}
}
// A major complication is the fact that some of the saturating add/subtract
// operations have Rd Rm Rn, instead of the "normal" Rd Rn Rm.
// They are QADD, QDADD, QDSUB, and QSUB.
static bool DisassembleDPFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
const MCInstrDesc &MCID = ARMInsts[Opcode];
unsigned short NumDefs = MCID.getNumDefs();
bool isUnary = isUnaryDP(MCID.TSFlags);
const MCOperandInfo *OpInfo = MCID.OpInfo;
unsigned &OpIdx = NumOpsAdded;
OpIdx = 0;
// Disassemble register def if there is one.
if (NumDefs && (OpInfo[OpIdx].RegClass == ARM::GPRRegClassID)) {
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRd(insn))));
++OpIdx;
}
// Now disassemble the src operands.
if (OpIdx >= NumOps)
return false;
// Special-case handling of BFC/BFI/SBFX/UBFX.
if (Opcode == ARM::BFC || Opcode == ARM::BFI) {
// A8.6.17 BFC & A8.6.18 BFI
// Sanity check Rd.
if (decodeRd(insn) == 15)
return false;
MI.addOperand(MCOperand::CreateReg(0));
if (Opcode == ARM::BFI) {
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRm(insn))));
++OpIdx;
}
uint32_t mask = 0;
if (!getBFCInvMask(insn, mask))
return false;
MI.addOperand(MCOperand::CreateImm(mask));
OpIdx += 2;
return true;
}
if (Opcode == ARM::SBFX || Opcode == ARM::UBFX) {
// Sanity check Rd and Rm.
if (decodeRd(insn) == 15 || decodeRm(insn) == 15)
return false;
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRm(insn))));
MI.addOperand(MCOperand::CreateImm(slice(insn, 11, 7)));
MI.addOperand(MCOperand::CreateImm(slice(insn, 20, 16) + 1));
OpIdx += 3;
return true;
}
bool RmRn = (Opcode == ARM::QADD || Opcode == ARM::QDADD ||
Opcode == ARM::QDSUB || Opcode == ARM::QSUB);
// BinaryDP has an Rn operand.
if (!isUnary) {
assert(OpInfo[OpIdx].RegClass == ARM::GPRRegClassID &&
"Reg operand expected");
MI.addOperand(MCOperand::CreateReg(
getRegisterEnum(B, ARM::GPRRegClassID,
RmRn ? decodeRm(insn) : decodeRn(insn))));
++OpIdx;
}
// If this is a two-address operand, skip it, e.g., MOVCCr operand 1.
if (isUnary && (MCID.getOperandConstraint(OpIdx, MCOI::TIED_TO) != -1)) {
MI.addOperand(MCOperand::CreateReg(0));
++OpIdx;
}
// Now disassemble operand 2.
if (OpIdx >= NumOps)
return false;
if (OpInfo[OpIdx].RegClass == ARM::GPRRegClassID) {
// We have a reg/reg form.
// Assert disabled because saturating operations, e.g., A8.6.127 QASX, are
// routed here as well.
// assert(getIBit(insn) == 0 && "I_Bit != '0' reg/reg form");
if (BadRegsDPFrm(Opcode, insn))
return false;
MI.addOperand(MCOperand::CreateReg(
getRegisterEnum(B, ARM::GPRRegClassID,
RmRn? decodeRn(insn) : decodeRm(insn))));
++OpIdx;
} else if (Opcode == ARM::MOVi16 || Opcode == ARM::MOVTi16) {
// These two instructions don't allow d as 15.
if (decodeRd(insn) == 15)
return false;
// We have an imm16 = imm4:imm12 (imm4=Inst{19:16}, imm12 = Inst{11:0}).
assert(getIBit(insn) == 1 && "I_Bit != '1' reg/imm form");
unsigned Imm16 = slice(insn, 19, 16) << 12 | slice(insn, 11, 0);
if (!B->tryAddingSymbolicOperand(Imm16, 4, MI))
MI.addOperand(MCOperand::CreateImm(Imm16));
++OpIdx;
} else {
// We have a reg/imm form.
// SOImm is 4-bit rotate amount in bits 11-8 with 8-bit imm in bits 7-0.
// A5.2.4 Rotate amount is twice the numeric value of Inst{11-8}.
// See also ARMAddressingModes.h: getSOImmValImm() and getSOImmValRot().
assert(getIBit(insn) == 1 && "I_Bit != '1' reg/imm form");
unsigned Rot = (insn >> ARMII::SoRotImmShift) & 0xF;
unsigned Imm = insn & 0xFF;
MI.addOperand(MCOperand::CreateImm(ARM_AM::rotr32(Imm, 2*Rot)));
++OpIdx;
}
return true;
}
static bool DisassembleDPSoRegFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
const MCInstrDesc &MCID = ARMInsts[Opcode];
unsigned short NumDefs = MCID.getNumDefs();
bool isUnary = isUnaryDP(MCID.TSFlags);
const MCOperandInfo *OpInfo = MCID.OpInfo;
unsigned &OpIdx = NumOpsAdded;
OpIdx = 0;
// Disassemble register def if there is one.
if (NumDefs && (OpInfo[OpIdx].RegClass == ARM::GPRRegClassID)) {
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRd(insn))));
++OpIdx;
}
// Disassemble the src operands.
if (OpIdx >= NumOps)
return false;
// BinaryDP has an Rn operand.
if (!isUnary) {
assert(OpInfo[OpIdx].RegClass == ARM::GPRRegClassID &&
"Reg operand expected");
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRn(insn))));
++OpIdx;
}
// If this is a two-address operand, skip it, e.g., MOVCCs operand 1.
if (isUnary && (MCID.getOperandConstraint(OpIdx, MCOI::TIED_TO) != -1)) {
MI.addOperand(MCOperand::CreateReg(0));
++OpIdx;
}
// Disassemble operand 2, which consists of three components.
if (OpIdx + 2 >= NumOps)
return false;
assert((OpInfo[OpIdx].RegClass == ARM::GPRRegClassID) &&
(OpInfo[OpIdx+1].RegClass == ARM::GPRRegClassID) &&
(OpInfo[OpIdx+2].RegClass < 0) &&
"Expect 3 reg operands");
// Register-controlled shifts have Inst{7} = 0 and Inst{4} = 1.
unsigned Rs = slice(insn, 4, 4);
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRm(insn))));
if (Rs) {
// If Inst{7} != 0, we should reject this insn as an invalid encoding.
if (slice(insn, 7, 7))
return false;
// A8.6.3 ADC (register-shifted register)
// if d == 15 || n == 15 || m == 15 || s == 15 then UNPREDICTABLE;
//
// This also accounts for shift instructions (register) where, fortunately,
// Inst{19-16} = 0b0000.
// A8.6.89 LSL (register)
// if d == 15 || n == 15 || m == 15 then UNPREDICTABLE;
if (decodeRd(insn) == 15 || decodeRn(insn) == 15 ||
decodeRm(insn) == 15 || decodeRs(insn) == 15)
return false;
// Register-controlled shifts: [Rm, Rs, shift].
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRs(insn))));
// Inst{6-5} encodes the shift opcode.
ARM_AM::ShiftOpc ShOp = getShiftOpcForBits(slice(insn, 6, 5));
MI.addOperand(MCOperand::CreateImm(ARM_AM::getSORegOpc(ShOp, 0)));
} else {
// Constant shifts: [Rm, reg0, shift_imm].
MI.addOperand(MCOperand::CreateReg(0)); // NoRegister
// Inst{6-5} encodes the shift opcode.
ARM_AM::ShiftOpc ShOp = getShiftOpcForBits(slice(insn, 6, 5));
// Inst{11-7} encodes the imm5 shift amount.
unsigned ShImm = slice(insn, 11, 7);
// A8.4.1. Possible rrx or shift amount of 32...
getImmShiftSE(ShOp, ShImm);
MI.addOperand(MCOperand::CreateImm(ARM_AM::getSORegOpc(ShOp, ShImm)));
}
OpIdx += 3;
return true;
}
static bool BadRegsLdStFrm(unsigned Opcode, uint32_t insn, bool Store, bool WBack,
bool Imm) {
const StringRef Name = ARMInsts[Opcode].Name;
unsigned Rt = decodeRd(insn);
unsigned Rn = decodeRn(insn);
unsigned Rm = decodeRm(insn);
unsigned P = getPBit(insn);
unsigned W = getWBit(insn);
if (Store) {
// Only STR (immediate, register) allows PC as the source.
if (Name.startswith("STRB") && Rt == 15) {
DEBUG(errs() << "if t == 15 then UNPREDICTABLE\n");
return true;
}
if (WBack && (Rn == 15 || Rn == Rt)) {
DEBUG(errs() << "if wback && (n == 15 || n == t) then UNPREDICTABLE\n");
return true;
}
if (!Imm && Rm == 15) {
DEBUG(errs() << "if m == 15 then UNPREDICTABLE\n");
return true;
}
} else {
// Only LDR (immediate, register) allows PC as the destination.
if (Name.startswith("LDRB") && Rt == 15) {
DEBUG(errs() << "if t == 15 then UNPREDICTABLE\n");
return true;
}
if (Imm) {
// Immediate
if (Rn == 15) {
// The literal form must be in offset mode; it's an encoding error
// otherwise.
if (!(P == 1 && W == 0)) {
DEBUG(errs() << "Ld literal form with !(P == 1 && W == 0)\n");
return true;
}
// LDRB (literal) does not allow PC as the destination.
if (Opcode != ARM::LDRi12 && Rt == 15) {
DEBUG(errs() << "if t == 15 then UNPREDICTABLE\n");
return true;
}
} else {
// Write back while Rn == Rt does not make sense.
if (WBack && (Rn == Rt)) {
DEBUG(errs() << "if wback && n == t then UNPREDICTABLE\n");
return true;
}
}
} else {
// Register
if (Rm == 15) {
DEBUG(errs() << "if m == 15 then UNPREDICTABLE\n");
return true;
}
if (WBack && (Rn == 15 || Rn == Rt)) {
DEBUG(errs() << "if wback && (n == 15 || n == t) then UNPREDICTABLE\n");
return true;
}
}
}
return false;
}
static bool DisassembleLdStFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, bool isStore, BO B) {
const MCInstrDesc &MCID = ARMInsts[Opcode];
bool isPrePost = isPrePostLdSt(MCID.TSFlags);
const MCOperandInfo *OpInfo = MCID.OpInfo;
if (!OpInfo) return false;
unsigned &OpIdx = NumOpsAdded;
OpIdx = 0;
assert(((!isStore && MCID.getNumDefs() > 0) ||
(isStore && (MCID.getNumDefs() == 0 || isPrePost)))
&& "Invalid arguments");
// Operand 0 of a pre- and post-indexed store is the address base writeback.
if (isPrePost && isStore) {
assert(OpInfo[OpIdx].RegClass == ARM::GPRRegClassID &&
"Reg operand expected");
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRn(insn))));
++OpIdx;
}
// Disassemble the dst/src operand.
if (OpIdx >= NumOps)
return false;
assert(OpInfo[OpIdx].RegClass == ARM::GPRRegClassID &&
"Reg operand expected");
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRd(insn))));
++OpIdx;
// After dst of a pre- and post-indexed load is the address base writeback.
if (isPrePost && !isStore) {
assert(OpInfo[OpIdx].RegClass == ARM::GPRRegClassID &&
"Reg operand expected");
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRn(insn))));
++OpIdx;
}
// Disassemble the base operand.
if (OpIdx >= NumOps)
return false;
assert(OpInfo[OpIdx].RegClass == ARM::GPRRegClassID &&
"Reg operand expected");
assert((!isPrePost || (MCID.getOperandConstraint(OpIdx, MCOI::TIED_TO) != -1))
&& "Index mode or tied_to operand expected");
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRn(insn))));
++OpIdx;
// For reg/reg form, base reg is followed by +/- reg shop imm.
// For immediate form, it is followed by +/- imm12.
// See also ARMAddressingModes.h (Addressing Mode #2).
if (OpIdx + 1 >= NumOps)
return false;
if (BadRegsLdStFrm(Opcode, insn, isStore, isPrePost, getIBit(insn)==0))
return false;
ARM_AM::AddrOpc AddrOpcode = getUBit(insn) ? ARM_AM::add : ARM_AM::sub;
unsigned IndexMode =
(MCID.TSFlags & ARMII::IndexModeMask) >> ARMII::IndexModeShift;
if (getIBit(insn) == 0) {
// For pre- and post-indexed case, add a reg0 operand (Addressing Mode #2).
// Otherwise, skip the reg operand since for addrmode_imm12, Rn has already
// been populated.
if (isPrePost) {
MI.addOperand(MCOperand::CreateReg(0));
OpIdx += 1;
}
unsigned Imm12 = slice(insn, 11, 0);
if (Opcode == ARM::LDRBi12 || Opcode == ARM::LDRi12 ||
Opcode == ARM::STRBi12 || Opcode == ARM::STRi12) {
// Disassemble the 12-bit immediate offset, which is the second operand in
// $addrmode_imm12 => (ops GPR:$base, i32imm:$offsimm).
int Offset = AddrOpcode == ARM_AM::add ? 1 * Imm12 : -1 * Imm12;
MI.addOperand(MCOperand::CreateImm(Offset));
} else {
// Disassemble the 12-bit immediate offset, which is the second operand in
// $am2offset => (ops GPR, i32imm).
unsigned Offset = ARM_AM::getAM2Opc(AddrOpcode, Imm12, ARM_AM::no_shift,
IndexMode);
MI.addOperand(MCOperand::CreateImm(Offset));
}
OpIdx += 1;
} else {
// If Inst{25} = 1 and Inst{4} != 0, we should reject this as invalid.
if (slice(insn,4,4) == 1)
return false;
// Disassemble the offset reg (Rm), shift type, and immediate shift length.
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRm(insn))));
// Inst{6-5} encodes the shift opcode.
ARM_AM::ShiftOpc ShOp = getShiftOpcForBits(slice(insn, 6, 5));
// Inst{11-7} encodes the imm5 shift amount.
unsigned ShImm = slice(insn, 11, 7);
// A8.4.1. Possible rrx or shift amount of 32...
getImmShiftSE(ShOp, ShImm);
MI.addOperand(MCOperand::CreateImm(
ARM_AM::getAM2Opc(AddrOpcode, ShImm, ShOp, IndexMode)));
OpIdx += 2;
}
return true;
}
static bool DisassembleLdFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
return DisassembleLdStFrm(MI, Opcode, insn, NumOps, NumOpsAdded, false, B);
}
static bool DisassembleStFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
return DisassembleLdStFrm(MI, Opcode, insn, NumOps, NumOpsAdded, true, B);
}
static bool HasDualReg(unsigned Opcode) {
switch (Opcode) {
default:
return false;
case ARM::LDRD: case ARM::LDRD_PRE: case ARM::LDRD_POST:
case ARM::STRD: case ARM::STRD_PRE: case ARM::STRD_POST:
return true;
}
}
static bool DisassembleLdStMiscFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, bool isStore, BO B) {
const MCInstrDesc &MCID = ARMInsts[Opcode];
bool isPrePost = isPrePostLdSt(MCID.TSFlags);
const MCOperandInfo *OpInfo = MCID.OpInfo;
if (!OpInfo) return false;
unsigned &OpIdx = NumOpsAdded;
OpIdx = 0;
assert(((!isStore && MCID.getNumDefs() > 0) ||
(isStore && (MCID.getNumDefs() == 0 || isPrePost)))
&& "Invalid arguments");
// Operand 0 of a pre- and post-indexed store is the address base writeback.
if (isPrePost && isStore) {
assert(OpInfo[OpIdx].RegClass == ARM::GPRRegClassID &&
"Reg operand expected");
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRn(insn))));
++OpIdx;
}
// Disassemble the dst/src operand.
if (OpIdx >= NumOps)
return false;
assert(OpInfo[OpIdx].RegClass == ARM::GPRRegClassID &&
"Reg operand expected");
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRd(insn))));
++OpIdx;
// Fill in LDRD and STRD's second operand Rt operand.
if (HasDualReg(Opcode)) {
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRd(insn) + 1)));
++OpIdx;
}
// After dst of a pre- and post-indexed load is the address base writeback.
if (isPrePost && !isStore) {
assert(OpInfo[OpIdx].RegClass == ARM::GPRRegClassID &&
"Reg operand expected");
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRn(insn))));
++OpIdx;
}
// Disassemble the base operand.
if (OpIdx >= NumOps)
return false;
assert(OpInfo[OpIdx].RegClass == ARM::GPRRegClassID &&
"Reg operand expected");
assert((!isPrePost || (MCID.getOperandConstraint(OpIdx, MCOI::TIED_TO) != -1))
&& "Offset mode or tied_to operand expected");
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRn(insn))));
++OpIdx;
// For reg/reg form, base reg is followed by +/- reg.
// For immediate form, it is followed by +/- imm8.
// See also ARMAddressingModes.h (Addressing Mode #3).
if (OpIdx + 1 >= NumOps)
return false;
assert((OpInfo[OpIdx].RegClass == ARM::GPRRegClassID) &&
(OpInfo[OpIdx+1].RegClass < 0) &&
"Expect 1 reg operand followed by 1 imm operand");
ARM_AM::AddrOpc AddrOpcode = getUBit(insn) ? ARM_AM::add : ARM_AM::sub;
unsigned IndexMode =
(MCID.TSFlags & ARMII::IndexModeMask) >> ARMII::IndexModeShift;
if (getAM3IBit(insn) == 1) {
MI.addOperand(MCOperand::CreateReg(0));
// Disassemble the 8-bit immediate offset.
unsigned Imm4H = (insn >> ARMII::ImmHiShift) & 0xF;
unsigned Imm4L = insn & 0xF;
unsigned Offset = ARM_AM::getAM3Opc(AddrOpcode, (Imm4H << 4) | Imm4L,
IndexMode);
MI.addOperand(MCOperand::CreateImm(Offset));
} else {
// Disassemble the offset reg (Rm).
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRm(insn))));
unsigned Offset = ARM_AM::getAM3Opc(AddrOpcode, 0, IndexMode);
MI.addOperand(MCOperand::CreateImm(Offset));
}
OpIdx += 2;
return true;
}
static bool DisassembleLdMiscFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
return DisassembleLdStMiscFrm(MI, Opcode, insn, NumOps, NumOpsAdded, false,
B);
}
static bool DisassembleStMiscFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
return DisassembleLdStMiscFrm(MI, Opcode, insn, NumOps, NumOpsAdded, true, B);
}
// The algorithm for disassembly of LdStMulFrm is different from others because
// it explicitly populates the two predicate operands after the base register.
// After that, we need to populate the reglist with each affected register
// encoded as an MCOperand.
static bool DisassembleLdStMulFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
assert(NumOps >= 4 && "LdStMulFrm expects NumOps >= 4");
NumOpsAdded = 0;
unsigned Base = getRegisterEnum(B, ARM::GPRRegClassID, decodeRn(insn));
// Writeback to base, if necessary.
if (Opcode == ARM::LDMIA_UPD || Opcode == ARM::STMIA_UPD ||
Opcode == ARM::LDMDA_UPD || Opcode == ARM::STMDA_UPD ||
Opcode == ARM::LDMDB_UPD || Opcode == ARM::STMDB_UPD ||
Opcode == ARM::LDMIB_UPD || Opcode == ARM::STMIB_UPD) {
MI.addOperand(MCOperand::CreateReg(Base));
++NumOpsAdded;
}
// Add the base register operand.
MI.addOperand(MCOperand::CreateReg(Base));
// Handling the two predicate operands before the reglist.
int64_t CondVal = getCondField(insn);
if (CondVal == 0xF)
return false;
MI.addOperand(MCOperand::CreateImm(CondVal));
MI.addOperand(MCOperand::CreateReg(ARM::CPSR));
NumOpsAdded += 3;
// Fill the variadic part of reglist.
unsigned RegListBits = insn & ((1 << 16) - 1);
for (unsigned i = 0; i < 16; ++i) {
if ((RegListBits >> i) & 1) {
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
i)));
++NumOpsAdded;
}
}
return true;
}
// LDREX, LDREXB, LDREXH: Rd Rn
// LDREXD: Rd Rd+1 Rn
// STREX, STREXB, STREXH: Rd Rm Rn
// STREXD: Rd Rm Rm+1 Rn
//
// SWP, SWPB: Rd Rm Rn
static bool DisassembleLdStExFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
const MCOperandInfo *OpInfo = ARMInsts[Opcode].OpInfo;
if (!OpInfo) return false;
unsigned &OpIdx = NumOpsAdded;
OpIdx = 0;
assert(NumOps >= 2
&& OpInfo[0].RegClass == ARM::GPRRegClassID
&& OpInfo[1].RegClass == ARM::GPRRegClassID
&& "Expect 2 reg operands");
bool isStore = slice(insn, 20, 20) == 0;
bool isDW = (Opcode == ARM::LDREXD || Opcode == ARM::STREXD);
// Add the destination operand.
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRd(insn))));
++OpIdx;
// Store register Exclusive needs a source operand.
if (isStore) {
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRm(insn))));
++OpIdx;
if (isDW) {
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRm(insn)+1)));
++OpIdx;
}
} else if (isDW) {
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRd(insn)+1)));
++OpIdx;
}
// Finally add the pointer operand.
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRn(insn))));
++OpIdx;
return true;
}
// Misc. Arithmetic Instructions.
// CLZ: Rd Rm
// PKHBT, PKHTB: Rd Rn Rm , LSL/ASR #imm5
// RBIT, REV, REV16, REVSH: Rd Rm
static bool DisassembleArithMiscFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
const MCOperandInfo *OpInfo = ARMInsts[Opcode].OpInfo;
unsigned &OpIdx = NumOpsAdded;
OpIdx = 0;
assert(NumOps >= 2
&& OpInfo[0].RegClass == ARM::GPRRegClassID
&& OpInfo[1].RegClass == ARM::GPRRegClassID
&& "Expect 2 reg operands");
bool ThreeReg = NumOps > 2 && OpInfo[2].RegClass == ARM::GPRRegClassID;
// Sanity check the registers, which should not be 15.
if (decodeRd(insn) == 15 || decodeRm(insn) == 15)
return false;
if (ThreeReg && decodeRn(insn) == 15)
return false;
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRd(insn))));
++OpIdx;
if (ThreeReg) {
assert(NumOps >= 4 && "Expect >= 4 operands");
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRn(insn))));
++OpIdx;
}
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRm(insn))));
++OpIdx;
// If there is still an operand info left which is an immediate operand, add
// an additional imm5 LSL/ASR operand.
if (ThreeReg && OpInfo[OpIdx].RegClass < 0
&& !OpInfo[OpIdx].isPredicate() && !OpInfo[OpIdx].isOptionalDef()) {
// Extract the 5-bit immediate field Inst{11-7}.
unsigned ShiftAmt = (insn >> ARMII::ShiftShift) & 0x1F;
ARM_AM::ShiftOpc Opc = ARM_AM::no_shift;
if (Opcode == ARM::PKHBT)
Opc = ARM_AM::lsl;
else if (Opcode == ARM::PKHTB)
Opc = ARM_AM::asr;
getImmShiftSE(Opc, ShiftAmt);
MI.addOperand(MCOperand::CreateImm(ARM_AM::getSORegOpc(Opc, ShiftAmt)));
++OpIdx;
}
return true;
}
/// DisassembleSatFrm - Disassemble saturate instructions:
/// SSAT, SSAT16, USAT, and USAT16.
static bool DisassembleSatFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
// A8.6.183 SSAT
// if d == 15 || n == 15 then UNPREDICTABLE;
if (decodeRd(insn) == 15 || decodeRm(insn) == 15)
return false;
const MCInstrDesc &MCID = ARMInsts[Opcode];
NumOpsAdded = MCID.getNumOperands() - 2; // ignore predicate operands
// Disassemble register def.
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRd(insn))));
unsigned Pos = slice(insn, 20, 16);
if (Opcode == ARM::SSAT || Opcode == ARM::SSAT16)
Pos += 1;
MI.addOperand(MCOperand::CreateImm(Pos));
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRm(insn))));
if (NumOpsAdded == 4) {
ARM_AM::ShiftOpc Opc = (slice(insn, 6, 6) != 0 ? ARM_AM::asr : ARM_AM::lsl);
// Inst{11-7} encodes the imm5 shift amount.
unsigned ShAmt = slice(insn, 11, 7);
if (ShAmt == 0) {
// A8.6.183. Possible ASR shift amount of 32...
if (Opc == ARM_AM::asr)
ShAmt = 32;
else
Opc = ARM_AM::no_shift;
}
MI.addOperand(MCOperand::CreateImm(ARM_AM::getSORegOpc(Opc, ShAmt)));
}
return true;
}
// Extend instructions.
// SXT* and UXT*: Rd [Rn] Rm [rot_imm].
// The 2nd operand register is Rn and the 3rd operand regsiter is Rm for the
// three register operand form. Otherwise, Rn=0b1111 and only Rm is used.
static bool DisassembleExtFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
// A8.6.220 SXTAB
// if d == 15 || m == 15 then UNPREDICTABLE;
if (decodeRd(insn) == 15 || decodeRm(insn) == 15)
return false;
const MCOperandInfo *OpInfo = ARMInsts[Opcode].OpInfo;
unsigned &OpIdx = NumOpsAdded;
OpIdx = 0;
assert(NumOps >= 2
&& OpInfo[0].RegClass == ARM::GPRRegClassID
&& OpInfo[1].RegClass == ARM::GPRRegClassID
&& "Expect 2 reg operands");
bool ThreeReg = NumOps > 2 && OpInfo[2].RegClass == ARM::GPRRegClassID;
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRd(insn))));
++OpIdx;
if (ThreeReg) {
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRn(insn))));
++OpIdx;
}
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRm(insn))));
++OpIdx;
// If there is still an operand info left which is an immediate operand, add
// an additional rotate immediate operand.
if (OpIdx < NumOps && OpInfo[OpIdx].RegClass < 0
&& !OpInfo[OpIdx].isPredicate() && !OpInfo[OpIdx].isOptionalDef()) {
// Extract the 2-bit rotate field Inst{11-10}.
unsigned rot = (insn >> ARMII::ExtRotImmShift) & 3;
// Rotation by 8, 16, or 24 bits.
MI.addOperand(MCOperand::CreateImm(rot << 3));
++OpIdx;
}
return true;
}
/////////////////////////////////////
// //
// Utility Functions For VFP //
// //
/////////////////////////////////////
// Extract/Decode Dd/Sd:
//
// SP => d = UInt(Vd:D)
// DP => d = UInt(D:Vd)
static unsigned decodeVFPRd(uint32_t insn, bool isSPVFP) {
return isSPVFP ? (decodeRd(insn) << 1 | getDBit(insn))
: (decodeRd(insn) | getDBit(insn) << 4);
}
// Extract/Decode Dn/Sn:
//
// SP => n = UInt(Vn:N)
// DP => n = UInt(N:Vn)
static unsigned decodeVFPRn(uint32_t insn, bool isSPVFP) {
return isSPVFP ? (decodeRn(insn) << 1 | getNBit(insn))
: (decodeRn(insn) | getNBit(insn) << 4);
}
// Extract/Decode Dm/Sm:
//
// SP => m = UInt(Vm:M)
// DP => m = UInt(M:Vm)
static unsigned decodeVFPRm(uint32_t insn, bool isSPVFP) {
return isSPVFP ? (decodeRm(insn) << 1 | getMBit(insn))
: (decodeRm(insn) | getMBit(insn) << 4);
}
// A7.5.1
static APInt VFPExpandImm(unsigned char byte, unsigned N) {
assert(N == 32 || N == 64);
uint64_t Result;
unsigned bit6 = slice(byte, 6, 6);
if (N == 32) {
Result = slice(byte, 7, 7) << 31 | slice(byte, 5, 0) << 19;
if (bit6)
Result |= 0x1f << 25;
else
Result |= 0x1 << 30;
} else {
Result = (uint64_t)slice(byte, 7, 7) << 63 |
(uint64_t)slice(byte, 5, 0) << 48;
if (bit6)
Result |= 0xffULL << 54;
else
Result |= 0x1ULL << 62;
}
return APInt(N, Result);
}
// VFP Unary Format Instructions:
//
// VCMP[E]ZD, VCMP[E]ZS: compares one floating-point register with zero
// VCVTDS, VCVTSD: converts between double-precision and single-precision
// The rest of the instructions have homogeneous [VFP]Rd and [VFP]Rm registers.
static bool DisassembleVFPUnaryFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
assert(NumOps >= 1 && "VFPUnaryFrm expects NumOps >= 1");
const MCOperandInfo *OpInfo = ARMInsts[Opcode].OpInfo;
unsigned &OpIdx = NumOpsAdded;
OpIdx = 0;
unsigned RegClass = OpInfo[OpIdx].RegClass;
assert((RegClass == ARM::SPRRegClassID || RegClass == ARM::DPRRegClassID) &&
"Reg operand expected");
bool isSP = (RegClass == ARM::SPRRegClassID);
MI.addOperand(MCOperand::CreateReg(
getRegisterEnum(B, RegClass, decodeVFPRd(insn, isSP))));
++OpIdx;
// Early return for compare with zero instructions.
if (Opcode == ARM::VCMPEZD || Opcode == ARM::VCMPEZS
|| Opcode == ARM::VCMPZD || Opcode == ARM::VCMPZS)
return true;
RegClass = OpInfo[OpIdx].RegClass;
assert((RegClass == ARM::SPRRegClassID || RegClass == ARM::DPRRegClassID) &&
"Reg operand expected");
isSP = (RegClass == ARM::SPRRegClassID);
MI.addOperand(MCOperand::CreateReg(
getRegisterEnum(B, RegClass, decodeVFPRm(insn, isSP))));
++OpIdx;
return true;
}
// All the instructions have homogeneous [VFP]Rd, [VFP]Rn, and [VFP]Rm regs.
// Some of them have operand constraints which tie the first operand in the
// InOperandList to that of the dst. As far as asm printing is concerned, this
// tied_to operand is simply skipped.
static bool DisassembleVFPBinaryFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
assert(NumOps >= 3 && "VFPBinaryFrm expects NumOps >= 3");
const MCInstrDesc &MCID = ARMInsts[Opcode];
const MCOperandInfo *OpInfo = MCID.OpInfo;
unsigned &OpIdx = NumOpsAdded;
OpIdx = 0;
unsigned RegClass = OpInfo[OpIdx].RegClass;
assert((RegClass == ARM::SPRRegClassID || RegClass == ARM::DPRRegClassID) &&
"Reg operand expected");
bool isSP = (RegClass == ARM::SPRRegClassID);
MI.addOperand(MCOperand::CreateReg(
getRegisterEnum(B, RegClass, decodeVFPRd(insn, isSP))));
++OpIdx;
// Skip tied_to operand constraint.
if (MCID.getOperandConstraint(OpIdx, MCOI::TIED_TO) != -1) {
assert(NumOps >= 4 && "Expect >=4 operands");
MI.addOperand(MCOperand::CreateReg(0));
++OpIdx;
}
MI.addOperand(MCOperand::CreateReg(
getRegisterEnum(B, RegClass, decodeVFPRn(insn, isSP))));
++OpIdx;
MI.addOperand(MCOperand::CreateReg(
getRegisterEnum(B, RegClass, decodeVFPRm(insn, isSP))));
++OpIdx;
return true;
}
// A8.6.295 vcvt (floating-point <-> integer)
// Int to FP: VSITOD, VSITOS, VUITOD, VUITOS
// FP to Int: VTOSI[Z|R]D, VTOSI[Z|R]S, VTOUI[Z|R]D, VTOUI[Z|R]S
//
// A8.6.297 vcvt (floating-point and fixed-point)
// Dd|Sd Dd|Sd(TIED_TO) #fbits(= 16|32 - UInt(imm4:i))
static bool DisassembleVFPConv1Frm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
assert(NumOps >= 2 && "VFPConv1Frm expects NumOps >= 2");
const MCInstrDesc &MCID = ARMInsts[Opcode];
const MCOperandInfo *OpInfo = MCID.OpInfo;
if (!OpInfo) return false;
bool SP = slice(insn, 8, 8) == 0; // A8.6.295 & A8.6.297
bool fixed_point = slice(insn, 17, 17) == 1; // A8.6.297
unsigned RegClassID = SP ? ARM::SPRRegClassID : ARM::DPRRegClassID;
if (fixed_point) {
// A8.6.297
assert(NumOps >= 3 && "Expect >= 3 operands");
int size = slice(insn, 7, 7) == 0 ? 16 : 32;
int fbits = size - (slice(insn,3,0) << 1 | slice(insn,5,5));
MI.addOperand(MCOperand::CreateReg(
getRegisterEnum(B, RegClassID,
decodeVFPRd(insn, SP))));
assert(MCID.getOperandConstraint(1, MCOI::TIED_TO) != -1 &&
"Tied to operand expected");
MI.addOperand(MI.getOperand(0));
assert(OpInfo[2].RegClass < 0 && !OpInfo[2].isPredicate() &&
!OpInfo[2].isOptionalDef() && "Imm operand expected");
MI.addOperand(MCOperand::CreateImm(fbits));
NumOpsAdded = 3;
} else {
// A8.6.295
// The Rd (destination) and Rm (source) bits have different interpretations
// depending on their single-precisonness.
unsigned d, m;
if (slice(insn, 18, 18) == 1) { // to_integer operation
d = decodeVFPRd(insn, true /* Is Single Precision */);
MI.addOperand(MCOperand::CreateReg(
getRegisterEnum(B, ARM::SPRRegClassID, d)));
m = decodeVFPRm(insn, SP);
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, RegClassID, m)));
} else {
d = decodeVFPRd(insn, SP);
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, RegClassID, d)));
m = decodeVFPRm(insn, true /* Is Single Precision */);
MI.addOperand(MCOperand::CreateReg(
getRegisterEnum(B, ARM::SPRRegClassID, m)));
}
NumOpsAdded = 2;
}
return true;
}
// VMOVRS - A8.6.330
// Rt => Rd; Sn => UInt(Vn:N)
static bool DisassembleVFPConv2Frm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
assert(NumOps >= 2 && "VFPConv2Frm expects NumOps >= 2");
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRd(insn))));
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::SPRRegClassID,
decodeVFPRn(insn, true))));
NumOpsAdded = 2;
return true;
}
// VMOVRRD - A8.6.332
// Rt => Rd; Rt2 => Rn; Dm => UInt(M:Vm)
//
// VMOVRRS - A8.6.331
// Rt => Rd; Rt2 => Rn; Sm => UInt(Vm:M); Sm1 = Sm+1
static bool DisassembleVFPConv3Frm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
assert(NumOps >= 3 && "VFPConv3Frm expects NumOps >= 3");
const MCOperandInfo *OpInfo = ARMInsts[Opcode].OpInfo;
unsigned &OpIdx = NumOpsAdded;
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRd(insn))));
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRn(insn))));
OpIdx = 2;
if (OpInfo[OpIdx].RegClass == ARM::SPRRegClassID) {
unsigned Sm = decodeVFPRm(insn, true);
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::SPRRegClassID,
Sm)));
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::SPRRegClassID,
Sm+1)));
OpIdx += 2;
} else {
MI.addOperand(MCOperand::CreateReg(
getRegisterEnum(B, ARM::DPRRegClassID,
decodeVFPRm(insn, false))));
++OpIdx;
}
return true;
}
// VMOVSR - A8.6.330
// Rt => Rd; Sn => UInt(Vn:N)
static bool DisassembleVFPConv4Frm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
assert(NumOps >= 2 && "VFPConv4Frm expects NumOps >= 2");
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::SPRRegClassID,
decodeVFPRn(insn, true))));
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRd(insn))));
NumOpsAdded = 2;
return true;
}
// VMOVDRR - A8.6.332
// Rt => Rd; Rt2 => Rn; Dm => UInt(M:Vm)
//
// VMOVRRS - A8.6.331
// Rt => Rd; Rt2 => Rn; Sm => UInt(Vm:M); Sm1 = Sm+1
static bool DisassembleVFPConv5Frm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
assert(NumOps >= 3 && "VFPConv5Frm expects NumOps >= 3");
const MCOperandInfo *OpInfo = ARMInsts[Opcode].OpInfo;
unsigned &OpIdx = NumOpsAdded;
OpIdx = 0;
if (OpInfo[OpIdx].RegClass == ARM::SPRRegClassID) {
unsigned Sm = decodeVFPRm(insn, true);
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::SPRRegClassID,
Sm)));
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::SPRRegClassID,
Sm+1)));
OpIdx += 2;
} else {
MI.addOperand(MCOperand::CreateReg(
getRegisterEnum(B, ARM::DPRRegClassID,
decodeVFPRm(insn, false))));
++OpIdx;
}
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRd(insn))));
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRn(insn))));
OpIdx += 2;
return true;
}
// VFP Load/Store Instructions.
// VLDRD, VLDRS, VSTRD, VSTRS
static bool DisassembleVFPLdStFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
assert(NumOps >= 3 && "VFPLdStFrm expects NumOps >= 3");
bool isSPVFP = (Opcode == ARM::VLDRS || Opcode == ARM::VSTRS);
unsigned RegClassID = isSPVFP ? ARM::SPRRegClassID : ARM::DPRRegClassID;
// Extract Dd/Sd for operand 0.
unsigned RegD = decodeVFPRd(insn, isSPVFP);
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, RegClassID, RegD)));
unsigned Base = getRegisterEnum(B, ARM::GPRRegClassID, decodeRn(insn));
MI.addOperand(MCOperand::CreateReg(Base));
// Next comes the AM5 Opcode.
ARM_AM::AddrOpc AddrOpcode = getUBit(insn) ? ARM_AM::add : ARM_AM::sub;
unsigned char Imm8 = insn & 0xFF;
MI.addOperand(MCOperand::CreateImm(ARM_AM::getAM5Opc(AddrOpcode, Imm8)));
NumOpsAdded = 3;
return true;
}
// VFP Load/Store Multiple Instructions.
// We have an optional write back reg, the base, and two predicate operands.
// It is then followed by a reglist of either DPR(s) or SPR(s).
//
// VLDMD[_UPD], VLDMS[_UPD], VSTMD[_UPD], VSTMS[_UPD]
static bool DisassembleVFPLdStMulFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
assert(NumOps >= 4 && "VFPLdStMulFrm expects NumOps >= 4");
unsigned &OpIdx = NumOpsAdded;
OpIdx = 0;
unsigned Base = getRegisterEnum(B, ARM::GPRRegClassID, decodeRn(insn));
// Writeback to base, if necessary.
if (Opcode == ARM::VLDMDIA_UPD || Opcode == ARM::VLDMSIA_UPD ||
Opcode == ARM::VLDMDDB_UPD || Opcode == ARM::VLDMSDB_UPD ||
Opcode == ARM::VSTMDIA_UPD || Opcode == ARM::VSTMSIA_UPD ||
Opcode == ARM::VSTMDDB_UPD || Opcode == ARM::VSTMSDB_UPD) {
MI.addOperand(MCOperand::CreateReg(Base));
++OpIdx;
}
MI.addOperand(MCOperand::CreateReg(Base));
// Handling the two predicate operands before the reglist.
int64_t CondVal = getCondField(insn);
if (CondVal == 0xF)
return false;
MI.addOperand(MCOperand::CreateImm(CondVal));
MI.addOperand(MCOperand::CreateReg(ARM::CPSR));
OpIdx += 3;
bool isSPVFP = (Opcode == ARM::VLDMSIA ||
Opcode == ARM::VLDMSIA_UPD || Opcode == ARM::VLDMSDB_UPD ||
Opcode == ARM::VSTMSIA ||
Opcode == ARM::VSTMSIA_UPD || Opcode == ARM::VSTMSDB_UPD);
unsigned RegClassID = isSPVFP ? ARM::SPRRegClassID : ARM::DPRRegClassID;
// Extract Dd/Sd.
unsigned RegD = decodeVFPRd(insn, isSPVFP);
// Fill the variadic part of reglist.
unsigned char Imm8 = insn & 0xFF;
unsigned Regs = isSPVFP ? Imm8 : Imm8/2;
// Apply some sanity checks before proceeding.
if (Regs == 0 || (RegD + Regs) > 32 || (!isSPVFP && Regs > 16))
return false;
for (unsigned i = 0; i < Regs; ++i) {
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, RegClassID,
RegD + i)));
++OpIdx;
}
return true;
}
// Misc. VFP Instructions.
// FMSTAT (vmrs with Rt=0b1111, i.e., to apsr_nzcv and no register operand)
// FCONSTD (DPR and a VFPf64Imm operand)
// FCONSTS (SPR and a VFPf32Imm operand)
// VMRS/VMSR (GPR operand)
static bool DisassembleVFPMiscFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
const MCOperandInfo *OpInfo = ARMInsts[Opcode].OpInfo;
unsigned &OpIdx = NumOpsAdded;
OpIdx = 0;
if (Opcode == ARM::FMSTAT)
return true;
assert(NumOps >= 2 && "VFPMiscFrm expects >=2 operands");
unsigned RegEnum = 0;
switch (OpInfo[0].RegClass) {
case ARM::DPRRegClassID:
RegEnum = getRegisterEnum(B, ARM::DPRRegClassID, decodeVFPRd(insn, false));
break;
case ARM::SPRRegClassID:
RegEnum = getRegisterEnum(B, ARM::SPRRegClassID, decodeVFPRd(insn, true));
break;
case ARM::GPRRegClassID:
RegEnum = getRegisterEnum(B, ARM::GPRRegClassID, decodeRd(insn));
break;
default:
assert(0 && "Invalid reg class id");
return false;
}
MI.addOperand(MCOperand::CreateReg(RegEnum));
++OpIdx;
// Extract/decode the f64/f32 immediate.
if (OpIdx < NumOps && OpInfo[OpIdx].RegClass < 0
&& !OpInfo[OpIdx].isPredicate() && !OpInfo[OpIdx].isOptionalDef()) {
// The asm syntax specifies the floating point value, not the 8-bit literal.
APInt immRaw = VFPExpandImm(slice(insn,19,16) << 4 | slice(insn, 3, 0),
Opcode == ARM::FCONSTD ? 64 : 32);
APFloat immFP = APFloat(immRaw, true);
double imm = Opcode == ARM::FCONSTD ? immFP.convertToDouble() :
immFP.convertToFloat();
MI.addOperand(MCOperand::CreateFPImm(imm));
++OpIdx;
}
return true;
}
// DisassembleThumbFrm() is defined in ThumbDisassemblerCore.h file.
#include "ThumbDisassemblerCore.h"
/////////////////////////////////////////////////////
// //
// Utility Functions For ARM Advanced SIMD //
// //
/////////////////////////////////////////////////////
// The following NEON namings are based on A8.6.266 VABA, VABAL. Notice that
// A8.6.303 VDUP (ARM core register)'s D/Vd pair is the N/Vn pair of VABA/VABAL.
// A7.3 Register encoding
// Extract/Decode NEON D/Vd:
//
// Note that for quadword, Qd = UInt(D:Vd<3:1>) = Inst{22:15-13}, whereas for
// doubleword, Dd = UInt(D:Vd). We compensate for this difference by
// handling it in the getRegisterEnum() utility function.
// D = Inst{22}, Vd = Inst{15-12}
static unsigned decodeNEONRd(uint32_t insn) {
return ((insn >> ARMII::NEON_D_BitShift) & 1) << 4
| ((insn >> ARMII::NEON_RegRdShift) & ARMII::NEONRegMask);
}
// Extract/Decode NEON N/Vn:
//
// Note that for quadword, Qn = UInt(N:Vn<3:1>) = Inst{7:19-17}, whereas for
// doubleword, Dn = UInt(N:Vn). We compensate for this difference by
// handling it in the getRegisterEnum() utility function.
// N = Inst{7}, Vn = Inst{19-16}
static unsigned decodeNEONRn(uint32_t insn) {
return ((insn >> ARMII::NEON_N_BitShift) & 1) << 4
| ((insn >> ARMII::NEON_RegRnShift) & ARMII::NEONRegMask);
}
// Extract/Decode NEON M/Vm:
//
// Note that for quadword, Qm = UInt(M:Vm<3:1>) = Inst{5:3-1}, whereas for
// doubleword, Dm = UInt(M:Vm). We compensate for this difference by
// handling it in the getRegisterEnum() utility function.
// M = Inst{5}, Vm = Inst{3-0}
static unsigned decodeNEONRm(uint32_t insn) {
return ((insn >> ARMII::NEON_M_BitShift) & 1) << 4
| ((insn >> ARMII::NEON_RegRmShift) & ARMII::NEONRegMask);
}
namespace {
enum ElemSize {
ESizeNA = 0,
ESize8 = 8,
ESize16 = 16,
ESize32 = 32,
ESize64 = 64
};
} // End of unnamed namespace
// size field -> Inst{11-10}
// index_align field -> Inst{7-4}
//
// The Lane Index interpretation depends on the Data Size:
// 8 (encoded as size = 0b00) -> Index = index_align[3:1]
// 16 (encoded as size = 0b01) -> Index = index_align[3:2]
// 32 (encoded as size = 0b10) -> Index = index_align[3]
//
// Ref: A8.6.317 VLD4 (single 4-element structure to one lane).
static unsigned decodeLaneIndex(uint32_t insn) {
unsigned size = insn >> 10 & 3;
assert((size == 0 || size == 1 || size == 2) &&
"Encoding error: size should be either 0, 1, or 2");
unsigned index_align = insn >> 4 & 0xF;
return (index_align >> 1) >> size;
}
// imm64 = AdvSIMDExpandImm(op, cmode, i:imm3:imm4)
// op = Inst{5}, cmode = Inst{11-8}
// i = Inst{24} (ARM architecture)
// imm3 = Inst{18-16}, imm4 = Inst{3-0}
// Ref: Table A7-15 Modified immediate values for Advanced SIMD instructions.
static uint64_t decodeN1VImm(uint32_t insn, ElemSize esize) {
unsigned char op = (insn >> 5) & 1;
unsigned char cmode = (insn >> 8) & 0xF;
unsigned char Imm8 = ((insn >> 24) & 1) << 7 |
((insn >> 16) & 7) << 4 |
(insn & 0xF);
return (op << 12) | (cmode << 8) | Imm8;
}
// A8.6.339 VMUL, VMULL (by scalar)
// ESize16 => m = Inst{2-0} (Vm<2:0>) D0-D7
// ESize32 => m = Inst{3-0} (Vm<3:0>) D0-D15
static unsigned decodeRestrictedDm(uint32_t insn, ElemSize esize) {
switch (esize) {
case ESize16:
return insn & 7;
case ESize32:
return insn & 0xF;
default:
assert(0 && "Unreachable code!");
return 0;
}
}
// A8.6.339 VMUL, VMULL (by scalar)
// ESize16 => index = Inst{5:3} (M:Vm<3>) D0-D7
// ESize32 => index = Inst{5} (M) D0-D15
static unsigned decodeRestrictedDmIndex(uint32_t insn, ElemSize esize) {
switch (esize) {
case ESize16:
return (((insn >> 5) & 1) << 1) | ((insn >> 3) & 1);
case ESize32:
return (insn >> 5) & 1;
default:
assert(0 && "Unreachable code!");
return 0;
}
}
// A8.6.296 VCVT (between floating-point and fixed-point, Advanced SIMD)
// (64 - <fbits>) is encoded as imm6, i.e., Inst{21-16}.
static unsigned decodeVCVTFractionBits(uint32_t insn) {
return 64 - ((insn >> 16) & 0x3F);
}
// A8.6.302 VDUP (scalar)
// ESize8 => index = Inst{19-17}
// ESize16 => index = Inst{19-18}
// ESize32 => index = Inst{19}
static unsigned decodeNVLaneDupIndex(uint32_t insn, ElemSize esize) {
switch (esize) {
case ESize8:
return (insn >> 17) & 7;
case ESize16:
return (insn >> 18) & 3;
case ESize32:
return (insn >> 19) & 1;
default:
assert(0 && "Unspecified element size!");
return 0;
}
}
// A8.6.328 VMOV (ARM core register to scalar)
// A8.6.329 VMOV (scalar to ARM core register)
// ESize8 => index = Inst{21:6-5}
// ESize16 => index = Inst{21:6}
// ESize32 => index = Inst{21}
static unsigned decodeNVLaneOpIndex(uint32_t insn, ElemSize esize) {
switch (esize) {
case ESize8:
return ((insn >> 21) & 1) << 2 | ((insn >> 5) & 3);
case ESize16:
return ((insn >> 21) & 1) << 1 | ((insn >> 6) & 1);
case ESize32:
return ((insn >> 21) & 1);
default:
assert(0 && "Unspecified element size!");
return 0;
}
}
// Imm6 = Inst{21-16}, L = Inst{7}
//
// LeftShift == true (A8.6.367 VQSHL, A8.6.387 VSLI):
// case L:imm6 of
// '0001xxx' => esize = 8; shift_amount = imm6 - 8
// '001xxxx' => esize = 16; shift_amount = imm6 - 16
// '01xxxxx' => esize = 32; shift_amount = imm6 - 32
// '1xxxxxx' => esize = 64; shift_amount = imm6
//
// LeftShift == false (A8.6.376 VRSHR, A8.6.368 VQSHRN):
// case L:imm6 of
// '0001xxx' => esize = 8; shift_amount = 16 - imm6
// '001xxxx' => esize = 16; shift_amount = 32 - imm6
// '01xxxxx' => esize = 32; shift_amount = 64 - imm6
// '1xxxxxx' => esize = 64; shift_amount = 64 - imm6
//
static unsigned decodeNVSAmt(uint32_t insn, bool LeftShift) {
ElemSize esize = ESizeNA;
unsigned L = (insn >> 7) & 1;
unsigned imm6 = (insn >> 16) & 0x3F;
if (L == 0) {
if (imm6 >> 3 == 1)
esize = ESize8;
else if (imm6 >> 4 == 1)
esize = ESize16;
else if (imm6 >> 5 == 1)
esize = ESize32;
else
assert(0 && "Wrong encoding of Inst{7:21-16}!");
} else
esize = ESize64;
if (LeftShift)
return esize == ESize64 ? imm6 : (imm6 - esize);
else
return esize == ESize64 ? (esize - imm6) : (2*esize - imm6);
}
// A8.6.305 VEXT
// Imm4 = Inst{11-8}
static unsigned decodeN3VImm(uint32_t insn) {
return (insn >> 8) & 0xF;
}
// VLD*
// D[d] D[d2] ... Rn [TIED_TO Rn] align [Rm]
// VLD*LN*
// D[d] D[d2] ... Rn [TIED_TO Rn] align [Rm] TIED_TO ... imm(idx)
// VST*
// Rn [TIED_TO Rn] align [Rm] D[d] D[d2] ...
// VST*LN*
// Rn [TIED_TO Rn] align [Rm] D[d] D[d2] ... [imm(idx)]
//
// Correctly set VLD*/VST*'s TIED_TO GPR, as the asm printer needs it.
static bool DisassembleNLdSt0(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, bool Store, bool DblSpaced,
unsigned alignment, BO B) {
const MCInstrDesc &MCID = ARMInsts[Opcode];
const MCOperandInfo *OpInfo = MCID.OpInfo;
// At least one DPR register plus addressing mode #6.
assert(NumOps >= 3 && "Expect >= 3 operands");
unsigned &OpIdx = NumOpsAdded;
OpIdx = 0;
// We have homogeneous NEON registers for Load/Store.
unsigned RegClass = 0;
// Double-spaced registers have increments of 2.
unsigned Inc = DblSpaced ? 2 : 1;
unsigned Rn = decodeRn(insn);
unsigned Rm = decodeRm(insn);
unsigned Rd = decodeNEONRd(insn);
// A7.7.1 Advanced SIMD addressing mode.
bool WB = Rm != 15;
// LLVM Addressing Mode #6.
unsigned RmEnum = 0;
if (WB && Rm != 13)
RmEnum = getRegisterEnum(B, ARM::GPRRegClassID, Rm);
if (Store) {
// Consume possible WB, AddrMode6, possible increment reg, the DPR/QPR's,
// then possible lane index.
assert(OpIdx < NumOps && OpInfo[0].RegClass == ARM::GPRRegClassID &&
"Reg operand expected");
if (WB) {
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
Rn)));
++OpIdx;
}
assert((OpIdx+1) < NumOps && OpInfo[OpIdx].RegClass == ARM::GPRRegClassID &&
OpInfo[OpIdx + 1].RegClass < 0 && "Addrmode #6 Operands expected");
// addrmode6 := (ops GPR:$addr, i32imm)
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
Rn)));
MI.addOperand(MCOperand::CreateImm(alignment)); // Alignment
OpIdx += 2;
if (WB) {
MI.addOperand(MCOperand::CreateReg(RmEnum));
++OpIdx;
}
assert(OpIdx < NumOps &&
(OpInfo[OpIdx].RegClass == ARM::DPRRegClassID ||
OpInfo[OpIdx].RegClass == ARM::QPRRegClassID) &&
"Reg operand expected");
RegClass = OpInfo[OpIdx].RegClass;
while (OpIdx < NumOps && (unsigned)OpInfo[OpIdx].RegClass == RegClass) {
MI.addOperand(MCOperand::CreateReg(
getRegisterEnum(B, RegClass, Rd)));
Rd += Inc;
++OpIdx;
}
// Handle possible lane index.
if (OpIdx < NumOps && OpInfo[OpIdx].RegClass < 0
&& !OpInfo[OpIdx].isPredicate() && !OpInfo[OpIdx].isOptionalDef()) {
MI.addOperand(MCOperand::CreateImm(decodeLaneIndex(insn)));
++OpIdx;
}
} else {
// Consume the DPR/QPR's, possible WB, AddrMode6, possible incrment reg,
// possible TIED_TO DPR/QPR's (ignored), then possible lane index.
RegClass = OpInfo[0].RegClass;
while (OpIdx < NumOps && (unsigned)OpInfo[OpIdx].RegClass == RegClass) {
MI.addOperand(MCOperand::CreateReg(
getRegisterEnum(B, RegClass, Rd)));
Rd += Inc;
++OpIdx;
}
if (WB) {
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
Rn)));
++OpIdx;
}
assert((OpIdx+1) < NumOps && OpInfo[OpIdx].RegClass == ARM::GPRRegClassID &&
OpInfo[OpIdx + 1].RegClass < 0 && "Addrmode #6 Operands expected");
// addrmode6 := (ops GPR:$addr, i32imm)
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
Rn)));
MI.addOperand(MCOperand::CreateImm(alignment)); // Alignment
OpIdx += 2;
if (WB) {
MI.addOperand(MCOperand::CreateReg(RmEnum));
++OpIdx;
}
while (OpIdx < NumOps && (unsigned)OpInfo[OpIdx].RegClass == RegClass) {
assert(MCID.getOperandConstraint(OpIdx, MCOI::TIED_TO) != -1 &&
"Tied to operand expected");
MI.addOperand(MCOperand::CreateReg(0));
++OpIdx;
}
// Handle possible lane index.
if (OpIdx < NumOps && OpInfo[OpIdx].RegClass < 0
&& !OpInfo[OpIdx].isPredicate() && !OpInfo[OpIdx].isOptionalDef()) {
MI.addOperand(MCOperand::CreateImm(decodeLaneIndex(insn)));
++OpIdx;
}
}
// Accessing registers past the end of the NEON register file is not
// defined.
if (Rd > 32)
return false;
return true;
}
// A8.6.308, A8.6.311, A8.6.314, A8.6.317.
static bool Align4OneLaneInst(unsigned elem, unsigned size,
unsigned index_align, unsigned & alignment) {
unsigned bits = 0;
switch (elem) {
default:
return false;
case 1:
// A8.6.308
if (size == 0)
return slice(index_align, 0, 0) == 0;
else if (size == 1) {
bits = slice(index_align, 1, 0);
if (bits != 0 && bits != 1)
return false;
if (bits == 1)
alignment = 16;
return true;
} else if (size == 2) {
bits = slice(index_align, 2, 0);
if (bits != 0 && bits != 3)
return false;
if (bits == 3)
alignment = 32;
return true;;
}
return true;
case 2:
// A8.6.311
if (size == 0) {
if (slice(index_align, 0, 0) == 1)
alignment = 16;
return true;
} if (size == 1) {
if (slice(index_align, 0, 0) == 1)
alignment = 32;
return true;
} else if (size == 2) {
if (slice(index_align, 1, 1) != 0)
return false;
if (slice(index_align, 0, 0) == 1)
alignment = 64;
return true;;
}
return true;
case 3:
// A8.6.314
if (size == 0) {
if (slice(index_align, 0, 0) != 0)
return false;
return true;
} if (size == 1) {
if (slice(index_align, 0, 0) != 0)
return false;
return true;
return true;
} else if (size == 2) {
if (slice(index_align, 1, 0) != 0)
return false;
return true;;
}
return true;
case 4:
// A8.6.317
if (size == 0) {
if (slice(index_align, 0, 0) == 1)
alignment = 32;
return true;
} if (size == 1) {
if (slice(index_align, 0, 0) == 1)
alignment = 64;
return true;
} else if (size == 2) {
bits = slice(index_align, 1, 0);
if (bits == 3)
return false;
if (bits == 1)
alignment = 64;
else if (bits == 2)
alignment = 128;
return true;;
}
return true;
}
}
// A7.7
// If L (Inst{21}) == 0, store instructions.
// Find out about double-spaced-ness of the Opcode and pass it on to
// DisassembleNLdSt0().
static bool DisassembleNLdSt(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
const StringRef Name = ARMInsts[Opcode].Name;
bool DblSpaced = false;
// 0 represents standard alignment, i.e., unaligned data access.
unsigned alignment = 0;
unsigned elem = 0; // legal values: {1, 2, 3, 4}
if (Name.startswith("VST1") || Name.startswith("VLD1"))
elem = 1;
if (Name.startswith("VST2") || Name.startswith("VLD2"))
elem = 2;
if (Name.startswith("VST3") || Name.startswith("VLD3"))
elem = 3;
if (Name.startswith("VST4") || Name.startswith("VLD4"))
elem = 4;
if (Name.find("LN") != std::string::npos) {
// To one lane instructions.
// See, for example, 8.6.317 VLD4 (single 4-element structure to one lane).
// Utility function takes number of elements, size, and index_align.
if (!Align4OneLaneInst(elem,
slice(insn, 11, 10),
slice(insn, 7, 4),
alignment))
return false;
// <size> == 16 && Inst{5} == 1 --> DblSpaced = true
if (Name.endswith("16") || Name.endswith("16_UPD"))
DblSpaced = slice(insn, 5, 5) == 1;
// <size> == 32 && Inst{6} == 1 --> DblSpaced = true
if (Name.endswith("32") || Name.endswith("32_UPD"))
DblSpaced = slice(insn, 6, 6) == 1;
} else if (Name.find("DUP") != std::string::npos) {
// Single element (or structure) to all lanes.
// Inst{9-8} encodes the number of element(s) in the structure, with:
// 0b00 (VLD1DUP) (for this, a bit makes sense only for data size 16 and 32.
// 0b01 (VLD2DUP)
// 0b10 (VLD3DUP) (for this, a bit must be encoded as 0)
// 0b11 (VLD4DUP)
//
// Inst{7-6} encodes the data size, with:
// 0b00 => 8, 0b01 => 16, 0b10 => 32
//
// Inst{4} (the a bit) encodes the align action (0: standard alignment)
unsigned elem = slice(insn, 9, 8) + 1;
unsigned a = slice(insn, 4, 4);
if (elem != 3) {
// 0b11 is not a valid encoding for Inst{7-6}.
if (slice(insn, 7, 6) == 3)
return false;
unsigned data_size = 8 << slice(insn, 7, 6);
// For VLD1DUP, a bit makes sense only for data size of 16 and 32.
if (a && data_size == 8)
return false;
// Now we can calculate the alignment!
if (a)
alignment = elem * data_size;
} else {
if (a) {
// A8.6.315 VLD3 (single 3-element structure to all lanes)
// The a bit must be encoded as 0.
return false;
}
}
} else {
// Multiple n-element structures with type encoded as Inst{11-8}.
// See, for example, A8.6.316 VLD4 (multiple 4-element structures).
// Inst{5-4} encodes alignment.
unsigned align = slice(insn, 5, 4);
switch (align) {
default:
break;
case 1:
alignment = 64; break;
case 2:
alignment = 128; break;
case 3:
alignment = 256; break;
}
unsigned type = slice(insn, 11, 8);
// Reject UNDEFINED instructions based on type and align.
// Plus set DblSpaced flag where appropriate.
switch (elem) {
default:
break;
case 1:
// n == 1
// A8.6.307 & A8.6.391
if ((type == 7 && slice(align, 1, 1) == 1) ||
(type == 10 && align == 3) ||
(type == 6 && slice(align, 1, 1) == 1))
return false;
break;
case 2:
// n == 2 && type == 0b1001 -> DblSpaced = true
// A8.6.310 & A8.6.393
if ((type == 8 || type == 9) && align == 3)
return false;
DblSpaced = (type == 9);
break;
case 3:
// n == 3 && type == 0b0101 -> DblSpaced = true
// A8.6.313 & A8.6.395
if (slice(insn, 7, 6) == 3 || slice(align, 1, 1) == 1)
return false;
DblSpaced = (type == 5);
break;
case 4:
// n == 4 && type == 0b0001 -> DblSpaced = true
// A8.6.316 & A8.6.397
if (slice(insn, 7, 6) == 3)
return false;
DblSpaced = (type == 1);
break;
}
}
return DisassembleNLdSt0(MI, Opcode, insn, NumOps, NumOpsAdded,
slice(insn, 21, 21) == 0, DblSpaced, alignment/8, B);
}
// VMOV (immediate)
// Qd/Dd imm
// VBIC (immediate)
// VORR (immediate)
// Qd/Dd imm src(=Qd/Dd)
static bool DisassembleN1RegModImmFrm(MCInst &MI, unsigned Opcode,
uint32_t insn, unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
const MCInstrDesc &MCID = ARMInsts[Opcode];
const MCOperandInfo *OpInfo = MCID.OpInfo;
assert(NumOps >= 2 &&
(OpInfo[0].RegClass == ARM::DPRRegClassID ||
OpInfo[0].RegClass == ARM::QPRRegClassID) &&
(OpInfo[1].RegClass < 0) &&
"Expect 1 reg operand followed by 1 imm operand");
// Qd/Dd = Inst{22:15-12} => NEON Rd
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, OpInfo[0].RegClass,
decodeNEONRd(insn))));
ElemSize esize = ESizeNA;
switch (Opcode) {
case ARM::VMOVv8i8:
case ARM::VMOVv16i8:
esize = ESize8;
break;
case ARM::VMOVv4i16:
case ARM::VMOVv8i16:
case ARM::VMVNv4i16:
case ARM::VMVNv8i16:
case ARM::VBICiv4i16:
case ARM::VBICiv8i16:
case ARM::VORRiv4i16:
case ARM::VORRiv8i16:
esize = ESize16;
break;
case ARM::VMOVv2i32:
case ARM::VMOVv4i32:
case ARM::VMVNv2i32:
case ARM::VMVNv4i32:
case ARM::VBICiv2i32:
case ARM::VBICiv4i32:
case ARM::VORRiv2i32:
case ARM::VORRiv4i32:
esize = ESize32;
break;
case ARM::VMOVv1i64:
case ARM::VMOVv2i64:
esize = ESize64;
break;
default:
assert(0 && "Unexpected opcode!");
return false;
}
// One register and a modified immediate value.
// Add the imm operand.
MI.addOperand(MCOperand::CreateImm(decodeN1VImm(insn, esize)));
NumOpsAdded = 2;
// VBIC/VORRiv*i* variants have an extra $src = $Vd to be filled in.
if (NumOps >= 3 &&
(OpInfo[2].RegClass == ARM::DPRRegClassID ||
OpInfo[2].RegClass == ARM::QPRRegClassID)) {
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, OpInfo[0].RegClass,
decodeNEONRd(insn))));
NumOpsAdded += 1;
}
return true;
}
namespace {
enum N2VFlag {
N2V_None,
N2V_VectorDupLane,
N2V_VectorConvert_Between_Float_Fixed
};
} // End of unnamed namespace
// Vector Convert [between floating-point and fixed-point]
// Qd/Dd Qm/Dm [fbits]
//
// Vector Duplicate Lane (from scalar to all elements) Instructions.
// VDUPLN16d, VDUPLN16q, VDUPLN32d, VDUPLN32q, VDUPLN8d, VDUPLN8q:
// Qd/Dd Dm index
//
// Vector Move Long:
// Qd Dm
//
// Vector Move Narrow:
// Dd Qm
//
// Others
static bool DisassembleNVdVmOptImm(MCInst &MI, unsigned Opc, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, N2VFlag Flag, BO B) {
const MCInstrDesc &MCID = ARMInsts[Opc];
const MCOperandInfo *OpInfo = MCID.OpInfo;
assert(NumOps >= 2 &&
(OpInfo[0].RegClass == ARM::DPRRegClassID ||
OpInfo[0].RegClass == ARM::QPRRegClassID) &&
(OpInfo[1].RegClass == ARM::DPRRegClassID ||
OpInfo[1].RegClass == ARM::QPRRegClassID) &&
"Expect >= 2 operands and first 2 as reg operands");
unsigned &OpIdx = NumOpsAdded;
OpIdx = 0;
ElemSize esize = ESizeNA;
if (Flag == N2V_VectorDupLane) {
// VDUPLN has its index embedded. Its size can be inferred from the Opcode.
assert(Opc >= ARM::VDUPLN16d && Opc <= ARM::VDUPLN8q &&
"Unexpected Opcode");
esize = (Opc == ARM::VDUPLN8d || Opc == ARM::VDUPLN8q) ? ESize8
: ((Opc == ARM::VDUPLN16d || Opc == ARM::VDUPLN16q) ? ESize16
: ESize32);
}
// Qd/Dd = Inst{22:15-12} => NEON Rd
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, OpInfo[OpIdx].RegClass,
decodeNEONRd(insn))));
++OpIdx;
// VPADAL...
if (MCID.getOperandConstraint(OpIdx, MCOI::TIED_TO) != -1) {
// TIED_TO operand.
MI.addOperand(MCOperand::CreateReg(0));
++OpIdx;
}
// Dm = Inst{5:3-0} => NEON Rm
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, OpInfo[OpIdx].RegClass,
decodeNEONRm(insn))));
++OpIdx;
// VZIP and others have two TIED_TO reg operands.
int Idx;
while (OpIdx < NumOps &&
(Idx = MCID.getOperandConstraint(OpIdx, MCOI::TIED_TO)) != -1) {
// Add TIED_TO operand.
MI.addOperand(MI.getOperand(Idx));
++OpIdx;
}
// Add the imm operand, if required.
if (OpIdx < NumOps && OpInfo[OpIdx].RegClass < 0
&& !OpInfo[OpIdx].isPredicate() && !OpInfo[OpIdx].isOptionalDef()) {
unsigned imm = 0xFFFFFFFF;
if (Flag == N2V_VectorDupLane)
imm = decodeNVLaneDupIndex(insn, esize);
if (Flag == N2V_VectorConvert_Between_Float_Fixed)
imm = decodeVCVTFractionBits(insn);
assert(imm != 0xFFFFFFFF && "Internal error");
MI.addOperand(MCOperand::CreateImm(imm));
++OpIdx;
}
return true;
}
static bool DisassembleN2RegFrm(MCInst &MI, unsigned Opc, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
return DisassembleNVdVmOptImm(MI, Opc, insn, NumOps, NumOpsAdded,
N2V_None, B);
}
static bool DisassembleNVCVTFrm(MCInst &MI, unsigned Opc, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
return DisassembleNVdVmOptImm(MI, Opc, insn, NumOps, NumOpsAdded,
N2V_VectorConvert_Between_Float_Fixed, B);
}
static bool DisassembleNVecDupLnFrm(MCInst &MI, unsigned Opc, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
return DisassembleNVdVmOptImm(MI, Opc, insn, NumOps, NumOpsAdded,
N2V_VectorDupLane, B);
}
// Vector Shift [Accumulate] Instructions.
// Qd/Dd [Qd/Dd (TIED_TO)] Qm/Dm ShiftAmt
//
// Vector Shift Left Long (with maximum shift count) Instructions.
// VSHLLi16, VSHLLi32, VSHLLi8: Qd Dm imm (== size)
//
static bool DisassembleNVectorShift(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, bool LeftShift, BO B) {
const MCInstrDesc &MCID = ARMInsts[Opcode];
const MCOperandInfo *OpInfo = MCID.OpInfo;
assert(NumOps >= 3 &&
(OpInfo[0].RegClass == ARM::DPRRegClassID ||
OpInfo[0].RegClass == ARM::QPRRegClassID) &&
(OpInfo[1].RegClass == ARM::DPRRegClassID ||
OpInfo[1].RegClass == ARM::QPRRegClassID) &&
"Expect >= 3 operands and first 2 as reg operands");
unsigned &OpIdx = NumOpsAdded;
OpIdx = 0;
// Qd/Dd = Inst{22:15-12} => NEON Rd
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, OpInfo[OpIdx].RegClass,
decodeNEONRd(insn))));
++OpIdx;
if (MCID.getOperandConstraint(OpIdx, MCOI::TIED_TO) != -1) {
// TIED_TO operand.
MI.addOperand(MCOperand::CreateReg(0));
++OpIdx;
}
assert((OpInfo[OpIdx].RegClass == ARM::DPRRegClassID ||
OpInfo[OpIdx].RegClass == ARM::QPRRegClassID) &&
"Reg operand expected");
// Qm/Dm = Inst{5:3-0} => NEON Rm
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, OpInfo[OpIdx].RegClass,
decodeNEONRm(insn))));
++OpIdx;
assert(OpInfo[OpIdx].RegClass < 0 && "Imm operand expected");
// Add the imm operand.
// VSHLL has maximum shift count as the imm, inferred from its size.
unsigned Imm;
switch (Opcode) {
default:
Imm = decodeNVSAmt(insn, LeftShift);
break;
case ARM::VSHLLi8:
Imm = 8;
break;
case ARM::VSHLLi16:
Imm = 16;
break;
case ARM::VSHLLi32:
Imm = 32;
break;
}
MI.addOperand(MCOperand::CreateImm(Imm));
++OpIdx;
return true;
}
// Left shift instructions.
static bool DisassembleN2RegVecShLFrm(MCInst &MI, unsigned Opcode,
uint32_t insn, unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
return DisassembleNVectorShift(MI, Opcode, insn, NumOps, NumOpsAdded, true,
B);
}
// Right shift instructions have different shift amount interpretation.
static bool DisassembleN2RegVecShRFrm(MCInst &MI, unsigned Opcode,
uint32_t insn, unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
return DisassembleNVectorShift(MI, Opcode, insn, NumOps, NumOpsAdded, false,
B);
}
namespace {
enum N3VFlag {
N3V_None,
N3V_VectorExtract,
N3V_VectorShift,
N3V_Multiply_By_Scalar
};
} // End of unnamed namespace
// NEON Three Register Instructions with Optional Immediate Operand
//
// Vector Extract Instructions.
// Qd/Dd Qn/Dn Qm/Dm imm4
//
// Vector Shift (Register) Instructions.
// Qd/Dd Qm/Dm Qn/Dn (notice the order of m, n)
//
// Vector Multiply [Accumulate/Subtract] [Long] By Scalar Instructions.
// Qd/Dd Qn/Dn RestrictedDm index
//
// Others
static bool DisassembleNVdVnVmOptImm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, N3VFlag Flag, BO B) {
const MCInstrDesc &MCID = ARMInsts[Opcode];
const MCOperandInfo *OpInfo = MCID.OpInfo;
// No checking for OpInfo[2] because of MOVDneon/MOVQ with only two regs.
assert(NumOps >= 3 &&
(OpInfo[0].RegClass == ARM::DPRRegClassID ||
OpInfo[0].RegClass == ARM::QPRRegClassID) &&
(OpInfo[1].RegClass == ARM::DPRRegClassID ||
OpInfo[1].RegClass == ARM::QPRRegClassID) &&
"Expect >= 3 operands and first 2 as reg operands");
unsigned &OpIdx = NumOpsAdded;
OpIdx = 0;
bool VdVnVm = Flag == N3V_VectorShift ? false : true;
bool IsImm4 = Flag == N3V_VectorExtract ? true : false;
bool IsDmRestricted = Flag == N3V_Multiply_By_Scalar ? true : false;
ElemSize esize = ESizeNA;
if (Flag == N3V_Multiply_By_Scalar) {
unsigned size = (insn >> 20) & 3;
if (size == 1) esize = ESize16;
if (size == 2) esize = ESize32;
assert (esize == ESize16 || esize == ESize32);
}
// Qd/Dd = Inst{22:15-12} => NEON Rd
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, OpInfo[OpIdx].RegClass,
decodeNEONRd(insn))));
++OpIdx;
// VABA, VABAL, VBSLd, VBSLq, ...
if (MCID.getOperandConstraint(OpIdx, MCOI::TIED_TO) != -1) {
// TIED_TO operand.
MI.addOperand(MCOperand::CreateReg(0));
++OpIdx;
}
// Dn = Inst{7:19-16} => NEON Rn
// or
// Dm = Inst{5:3-0} => NEON Rm
MI.addOperand(MCOperand::CreateReg(
getRegisterEnum(B, OpInfo[OpIdx].RegClass,
VdVnVm ? decodeNEONRn(insn)
: decodeNEONRm(insn))));
++OpIdx;
// Dm = Inst{5:3-0} => NEON Rm
// or
// Dm is restricted to D0-D7 if size is 16, D0-D15 otherwise
// or
// Dn = Inst{7:19-16} => NEON Rn
unsigned m = VdVnVm ? (IsDmRestricted ? decodeRestrictedDm(insn, esize)
: decodeNEONRm(insn))
: decodeNEONRn(insn);
MI.addOperand(MCOperand::CreateReg(
getRegisterEnum(B, OpInfo[OpIdx].RegClass, m)));
++OpIdx;
if (OpIdx < NumOps && OpInfo[OpIdx].RegClass < 0
&& !OpInfo[OpIdx].isPredicate() && !OpInfo[OpIdx].isOptionalDef()) {
// Add the imm operand.
unsigned Imm = 0;
if (IsImm4)
Imm = decodeN3VImm(insn);
else if (IsDmRestricted)
Imm = decodeRestrictedDmIndex(insn, esize);
else {
assert(0 && "Internal error: unreachable code!");
return false;
}
MI.addOperand(MCOperand::CreateImm(Imm));
++OpIdx;
}
return true;
}
static bool DisassembleN3RegFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
return DisassembleNVdVnVmOptImm(MI, Opcode, insn, NumOps, NumOpsAdded,
N3V_None, B);
}
static bool DisassembleN3RegVecShFrm(MCInst &MI, unsigned Opcode,
uint32_t insn, unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
return DisassembleNVdVnVmOptImm(MI, Opcode, insn, NumOps, NumOpsAdded,
N3V_VectorShift, B);
}
static bool DisassembleNVecExtractFrm(MCInst &MI, unsigned Opcode,
uint32_t insn, unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
return DisassembleNVdVnVmOptImm(MI, Opcode, insn, NumOps, NumOpsAdded,
N3V_VectorExtract, B);
}
static bool DisassembleNVecMulScalarFrm(MCInst &MI, unsigned Opcode,
uint32_t insn, unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
return DisassembleNVdVnVmOptImm(MI, Opcode, insn, NumOps, NumOpsAdded,
N3V_Multiply_By_Scalar, B);
}
// Vector Table Lookup
//
// VTBL1, VTBX1: Dd [Dd(TIED_TO)] Dn Dm
// VTBL2, VTBX2: Dd [Dd(TIED_TO)] Dn Dn+1 Dm
// VTBL3, VTBX3: Dd [Dd(TIED_TO)] Dn Dn+1 Dn+2 Dm
// VTBL4, VTBX4: Dd [Dd(TIED_TO)] Dn Dn+1 Dn+2 Dn+3 Dm
static bool DisassembleNVTBLFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
const MCInstrDesc &MCID = ARMInsts[Opcode];
const MCOperandInfo *OpInfo = MCID.OpInfo;
if (!OpInfo) return false;
assert(NumOps >= 3 &&
OpInfo[0].RegClass == ARM::DPRRegClassID &&
OpInfo[1].RegClass == ARM::DPRRegClassID &&
OpInfo[2].RegClass == ARM::DPRRegClassID &&
"Expect >= 3 operands and first 3 as reg operands");
unsigned &OpIdx = NumOpsAdded;
OpIdx = 0;
unsigned Rn = decodeNEONRn(insn);
// {Dn} encoded as len = 0b00
// {Dn Dn+1} encoded as len = 0b01
// {Dn Dn+1 Dn+2 } encoded as len = 0b10
// {Dn Dn+1 Dn+2 Dn+3} encoded as len = 0b11
unsigned Len = slice(insn, 9, 8) + 1;
// Dd (the destination vector)
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::DPRRegClassID,
decodeNEONRd(insn))));
++OpIdx;
// Process tied_to operand constraint.
int Idx;
if ((Idx = MCID.getOperandConstraint(OpIdx, MCOI::TIED_TO)) != -1) {
MI.addOperand(MI.getOperand(Idx));
++OpIdx;
}
// Do the <list> now.
for (unsigned i = 0; i < Len; ++i) {
assert(OpIdx < NumOps && OpInfo[OpIdx].RegClass == ARM::DPRRegClassID &&
"Reg operand expected");
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::DPRRegClassID,
Rn + i)));
++OpIdx;
}
// Dm (the index vector)
assert(OpIdx < NumOps && OpInfo[OpIdx].RegClass == ARM::DPRRegClassID &&
"Reg operand (index vector) expected");
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::DPRRegClassID,
decodeNEONRm(insn))));
++OpIdx;
return true;
}
// Vector Get Lane (move scalar to ARM core register) Instructions.
// VGETLNi32, VGETLNs16, VGETLNs8, VGETLNu16, VGETLNu8: Rt Dn index
static bool DisassembleNGetLnFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
const MCInstrDesc &MCID = ARMInsts[Opcode];
const MCOperandInfo *OpInfo = MCID.OpInfo;
if (!OpInfo) return false;
assert(MCID.getNumDefs() == 1 && NumOps >= 3 &&
OpInfo[0].RegClass == ARM::GPRRegClassID &&
OpInfo[1].RegClass == ARM::DPRRegClassID &&
OpInfo[2].RegClass < 0 &&
"Expect >= 3 operands with one dst operand");
ElemSize esize =
Opcode == ARM::VGETLNi32 ? ESize32
: ((Opcode == ARM::VGETLNs16 || Opcode == ARM::VGETLNu16) ? ESize16
: ESize8);
// Rt = Inst{15-12} => ARM Rd
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRd(insn))));
// Dn = Inst{7:19-16} => NEON Rn
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::DPRRegClassID,
decodeNEONRn(insn))));
MI.addOperand(MCOperand::CreateImm(decodeNVLaneOpIndex(insn, esize)));
NumOpsAdded = 3;
return true;
}
// Vector Set Lane (move ARM core register to scalar) Instructions.
// VSETLNi16, VSETLNi32, VSETLNi8: Dd Dd (TIED_TO) Rt index
static bool DisassembleNSetLnFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
const MCInstrDesc &MCID = ARMInsts[Opcode];
const MCOperandInfo *OpInfo = MCID.OpInfo;
if (!OpInfo) return false;
assert(MCID.getNumDefs() == 1 && NumOps >= 3 &&
OpInfo[0].RegClass == ARM::DPRRegClassID &&
OpInfo[1].RegClass == ARM::DPRRegClassID &&
MCID.getOperandConstraint(1, MCOI::TIED_TO) != -1 &&
OpInfo[2].RegClass == ARM::GPRRegClassID &&
OpInfo[3].RegClass < 0 &&
"Expect >= 3 operands with one dst operand");
ElemSize esize =
Opcode == ARM::VSETLNi8 ? ESize8
: (Opcode == ARM::VSETLNi16 ? ESize16
: ESize32);
// Dd = Inst{7:19-16} => NEON Rn
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::DPRRegClassID,
decodeNEONRn(insn))));
// TIED_TO operand.
MI.addOperand(MCOperand::CreateReg(0));
// Rt = Inst{15-12} => ARM Rd
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRd(insn))));
MI.addOperand(MCOperand::CreateImm(decodeNVLaneOpIndex(insn, esize)));
NumOpsAdded = 4;
return true;
}
// Vector Duplicate Instructions (from ARM core register to all elements).
// VDUP8d, VDUP16d, VDUP32d, VDUP8q, VDUP16q, VDUP32q: Qd/Dd Rt
static bool DisassembleNDupFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
const MCOperandInfo *OpInfo = ARMInsts[Opcode].OpInfo;
assert(NumOps >= 2 &&
(OpInfo[0].RegClass == ARM::DPRRegClassID ||
OpInfo[0].RegClass == ARM::QPRRegClassID) &&
OpInfo[1].RegClass == ARM::GPRRegClassID &&
"Expect >= 2 operands and first 2 as reg operand");
unsigned RegClass = OpInfo[0].RegClass;
// Qd/Dd = Inst{7:19-16} => NEON Rn
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, RegClass,
decodeNEONRn(insn))));
// Rt = Inst{15-12} => ARM Rd
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRd(insn))));
NumOpsAdded = 2;
return true;
}
static inline bool PreLoadOpcode(unsigned Opcode) {
switch(Opcode) {
case ARM::PLDi12: case ARM::PLDrs:
case ARM::PLDWi12: case ARM::PLDWrs:
case ARM::PLIi12: case ARM::PLIrs:
return true;
default:
return false;
}
}
static bool DisassemblePreLoadFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
// Preload Data/Instruction requires either 2 or 3 operands.
// PLDi12, PLDWi12, PLIi12: addrmode_imm12
// PLDrs, PLDWrs, PLIrs: ldst_so_reg
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRn(insn))));
if (Opcode == ARM::PLDi12 || Opcode == ARM::PLDWi12
|| Opcode == ARM::PLIi12) {
unsigned Imm12 = slice(insn, 11, 0);
bool Negative = getUBit(insn) == 0;
// A8.6.118 PLD (literal) PLDWi12 with Rn=PC is transformed to PLDi12.
if (Opcode == ARM::PLDWi12 && slice(insn, 19, 16) == 0xF) {
DEBUG(errs() << "Rn == '1111': PLDWi12 morphed to PLDi12\n");
MI.setOpcode(ARM::PLDi12);
}
// -0 is represented specially. All other values are as normal.
int Offset = Negative ? -1 * Imm12 : Imm12;
if (Imm12 == 0 && Negative)
Offset = INT32_MIN;
MI.addOperand(MCOperand::CreateImm(Offset));
NumOpsAdded = 2;
} else {
MI.addOperand(MCOperand::CreateReg(getRegisterEnum(B, ARM::GPRRegClassID,
decodeRm(insn))));
ARM_AM::AddrOpc AddrOpcode = getUBit(insn) ? ARM_AM::add : ARM_AM::sub;
// Inst{6-5} encodes the shift opcode.
ARM_AM::ShiftOpc ShOp = getShiftOpcForBits(slice(insn, 6, 5));
// Inst{11-7} encodes the imm5 shift amount.
unsigned ShImm = slice(insn, 11, 7);
// A8.4.1. Possible rrx or shift amount of 32...
getImmShiftSE(ShOp, ShImm);
MI.addOperand(MCOperand::CreateImm(
ARM_AM::getAM2Opc(AddrOpcode, ShImm, ShOp)));
NumOpsAdded = 3;
}
return true;
}
static bool DisassembleMiscFrm(MCInst &MI, unsigned Opcode, uint32_t insn,
unsigned short NumOps, unsigned &NumOpsAdded, BO B) {
if (Opcode == ARM::DMB || Opcode == ARM::DSB || Opcode == ARM::ISB) {
// Inst{3-0} encodes the memory barrier option for the variants.
unsigned opt = slice(insn, 3, 0);
switch (opt) {
case ARM_MB::SY: case ARM_MB::ST:
case ARM_MB::ISH: case ARM_MB::ISHST:
case ARM_MB::NSH: case ARM_MB::NSHST:
case ARM_MB::OSH: case ARM_MB::OSHST:
MI.addOperand(MCOperand::CreateImm(opt));
NumOpsAdded = 1;
return true;
default:
return false;
}
}
switch (Opcode) {
case ARM::CLREX:
case ARM::NOP:
case ARM::TRAP:
case ARM::YIELD:
case ARM::WFE:
case ARM::WFI:
case ARM::SEV:
return true;
case ARM::SWP:
case ARM::SWPB:
// SWP, SWPB: Rd Rm Rn
// Delegate to DisassembleLdStExFrm()....
return DisassembleLdStExFrm(MI, Opcode, insn, NumOps, NumOpsAdded, B);
default:
break;
}
if (Opcode == ARM::SETEND) {
NumOpsAdded = 1;
MI.addOperand(MCOperand::CreateImm(slice(insn, 9, 9)));
return true;
}
// FIXME: To enable correct asm parsing and disasm of CPS we need 3 different
// opcodes which match the same real instruction. This is needed since there's
// no current handling of optional arguments. Fix here when a better handling
// of optional arguments is implemented.
if (Opcode == ARM::CPS3p) { // M = 1
// Let's reject these impossible imod values by returning false:
// 1. (imod=0b01)
//
// AsmPrinter cannot handle imod=0b00, plus (imod=0b00,M=1,iflags!=0) is an
// invalid combination, so we just check for imod=0b00 here.
if (slice(insn, 19, 18) == 0 || slice(insn, 19, 18) == 1)
return false;
MI.addOperand(MCOperand::CreateImm(slice(insn, 19, 18))); // imod
MI.addOperand(MCOperand::CreateImm(slice(insn, 8, 6))); // iflags
MI.addOperand(MCOperand::CreateImm(slice(insn, 4, 0))); // mode
NumOpsAdded = 3;
return true;
}
if (Opcode == ARM::CPS2p) { // mode = 0, M = 0
// Let's reject these impossible imod values by returning false:
// 1. (imod=0b00,M=0)
// 2. (imod=0b01)
if (slice(insn, 19, 18) == 0 || slice(insn, 19, 18) == 1)
return false;
MI.addOperand(MCOperand::CreateImm(slice(insn, 19, 18))); // imod
MI.addOperand(MCOperand::CreateImm(slice(insn, 8, 6))); // iflags
NumOpsAdded = 2;
return true;
}
if (Opcode == ARM::CPS1p) { // imod = 0, iflags = 0, M = 1
MI.addOperand(MCOperand::CreateImm(slice(insn, 4, 0))); // mode
NumOpsAdded = 1;
return true;
}
// DBG has its option specified in Inst{3-0}.
if (Opcode == ARM::DBG) {
MI.addOperand(MCOperand::CreateImm(slice(insn, 3, 0)));
NumOpsAdded = 1;
return true;
}
// BKPT takes an imm32 val equal to ZeroExtend(Inst{19-8:3-0}).
if (Opcode == ARM::BKPT) {
MI.addOperand(MCOperand::CreateImm(slice(insn, 19, 8) << 4 |
slice(insn, 3, 0)));
NumOpsAdded = 1;
return true;
}
if (PreLoadOpcode(Opcode))
return DisassemblePreLoadFrm(MI, Opcode, insn, NumOps, NumOpsAdded, B);
assert(0 && "Unexpected misc instruction!");
return false;
}
/// FuncPtrs - FuncPtrs maps ARMFormat to its corresponding DisassembleFP.
/// We divide the disassembly task into different categories, with each one
/// corresponding to a specific instruction encoding format. There could be
/// exceptions when handling a specific format, and that is why the Opcode is
/// also present in the function prototype.
static const DisassembleFP FuncPtrs[] = {
&DisassemblePseudo,
&DisassembleMulFrm,
&DisassembleBrFrm,
&DisassembleBrMiscFrm,
&DisassembleDPFrm,
&DisassembleDPSoRegFrm,
&DisassembleLdFrm,
&DisassembleStFrm,
&DisassembleLdMiscFrm,
&DisassembleStMiscFrm,
&DisassembleLdStMulFrm,
&DisassembleLdStExFrm,
&DisassembleArithMiscFrm,
&DisassembleSatFrm,
&DisassembleExtFrm,
&DisassembleVFPUnaryFrm,
&DisassembleVFPBinaryFrm,
&DisassembleVFPConv1Frm,
&DisassembleVFPConv2Frm,
&DisassembleVFPConv3Frm,
&DisassembleVFPConv4Frm,
&DisassembleVFPConv5Frm,
&DisassembleVFPLdStFrm,
&DisassembleVFPLdStMulFrm,
&DisassembleVFPMiscFrm,
&DisassembleThumbFrm,
&DisassembleMiscFrm,
&DisassembleNGetLnFrm,
&DisassembleNSetLnFrm,
&DisassembleNDupFrm,
// VLD and VST (including one lane) Instructions.
&DisassembleNLdSt,
// A7.4.6 One register and a modified immediate value
// 1-Register Instructions with imm.
// LLVM only defines VMOVv instructions.
&DisassembleN1RegModImmFrm,
// 2-Register Instructions with no imm.
&DisassembleN2RegFrm,
// 2-Register Instructions with imm (vector convert float/fixed point).
&DisassembleNVCVTFrm,
// 2-Register Instructions with imm (vector dup lane).
&DisassembleNVecDupLnFrm,
// Vector Shift Left Instructions.
&DisassembleN2RegVecShLFrm,
// Vector Shift Righ Instructions, which has different interpretation of the
// shift amount from the imm6 field.
&DisassembleN2RegVecShRFrm,
// 3-Register Data-Processing Instructions.
&DisassembleN3RegFrm,
// Vector Shift (Register) Instructions.
// D:Vd M:Vm N:Vn (notice that M:Vm is the first operand)
&DisassembleN3RegVecShFrm,
// Vector Extract Instructions.
&DisassembleNVecExtractFrm,
// Vector [Saturating Rounding Doubling] Multiply [Accumulate/Subtract] [Long]
// By Scalar Instructions.
&DisassembleNVecMulScalarFrm,
// Vector Table Lookup uses byte indexes in a control vector to look up byte
// values in a table and generate a new vector.
&DisassembleNVTBLFrm,
NULL
};
/// BuildIt - BuildIt performs the build step for this ARM Basic MC Builder.
/// The general idea is to set the Opcode for the MCInst, followed by adding
/// the appropriate MCOperands to the MCInst. ARM Basic MC Builder delegates
/// to the Format-specific disassemble function for disassembly, followed by
/// TryPredicateAndSBitModifier() to do PredicateOperand and OptionalDefOperand
/// which follow the Dst/Src Operands.
bool ARMBasicMCBuilder::BuildIt(MCInst &MI, uint32_t insn) {
// Stage 1 sets the Opcode.
MI.setOpcode(Opcode);
// If the number of operands is zero, we're done!
if (NumOps == 0)
return true;
// Stage 2 calls the format-specific disassemble function to build the operand
// list.
if (Disasm == NULL)
return false;
unsigned NumOpsAdded = 0;
bool OK = (*Disasm)(MI, Opcode, insn, NumOps, NumOpsAdded, this);
if (!OK || this->Err != 0) return false;
if (NumOpsAdded >= NumOps)
return true;
// Stage 3 deals with operands unaccounted for after stage 2 is finished.
// FIXME: Should this be done selectively?
return TryPredicateAndSBitModifier(MI, Opcode, insn, NumOps - NumOpsAdded);
}
// A8.3 Conditional execution
// A8.3.1 Pseudocode details of conditional execution
// Condition bits '111x' indicate the instruction is always executed.
static uint32_t CondCode(uint32_t CondField) {
if (CondField == 0xF)
return ARMCC::AL;
return CondField;
}
/// DoPredicateOperands - DoPredicateOperands process the predicate operands
/// of some Thumb instructions which come before the reglist operands. It
/// returns true if the two predicate operands have been processed.
bool ARMBasicMCBuilder::DoPredicateOperands(MCInst& MI, unsigned Opcode,
uint32_t /* insn */, unsigned short NumOpsRemaining) {
assert(NumOpsRemaining > 0 && "Invalid argument");
const MCOperandInfo *OpInfo = ARMInsts[Opcode].OpInfo;
unsigned Idx = MI.getNumOperands();
// First, we check whether this instr specifies the PredicateOperand through
// a pair of MCOperandInfos with isPredicate() property.
if (NumOpsRemaining >= 2 &&
OpInfo[Idx].isPredicate() && OpInfo[Idx+1].isPredicate() &&
OpInfo[Idx].RegClass < 0 &&
OpInfo[Idx+1].RegClass == ARM::CCRRegClassID)
{
// If we are inside an IT block, get the IT condition bits maintained via
// ARMBasicMCBuilder::ITState[7:0], through ARMBasicMCBuilder::GetITCond().
// See also A2.5.2.
if (InITBlock())
MI.addOperand(MCOperand::CreateImm(GetITCond()));
else
MI.addOperand(MCOperand::CreateImm(ARMCC::AL));
MI.addOperand(MCOperand::CreateReg(ARM::CPSR));
return true;
}
return false;
}
/// TryPredicateAndSBitModifier - TryPredicateAndSBitModifier tries to process
/// the possible Predicate and SBitModifier, to build the remaining MCOperand
/// constituents.
bool ARMBasicMCBuilder::TryPredicateAndSBitModifier(MCInst& MI, unsigned Opcode,
uint32_t insn, unsigned short NumOpsRemaining) {
assert(NumOpsRemaining > 0 && "Invalid argument");
const MCOperandInfo *OpInfo = ARMInsts[Opcode].OpInfo;
const std::string &Name = ARMInsts[Opcode].Name;
unsigned Idx = MI.getNumOperands();
uint64_t TSFlags = ARMInsts[Opcode].TSFlags;
// First, we check whether this instr specifies the PredicateOperand through
// a pair of MCOperandInfos with isPredicate() property.
if (NumOpsRemaining >= 2 &&
OpInfo[Idx].isPredicate() && OpInfo[Idx+1].isPredicate() &&
OpInfo[Idx].RegClass < 0 &&
OpInfo[Idx+1].RegClass == ARM::CCRRegClassID)
{
// If we are inside an IT block, get the IT condition bits maintained via
// ARMBasicMCBuilder::ITState[7:0], through ARMBasicMCBuilder::GetITCond().
// See also A2.5.2.
if (InITBlock())
MI.addOperand(MCOperand::CreateImm(GetITCond()));
else {
if (Name.length() > 1 && Name[0] == 't') {
// Thumb conditional branch instructions have their cond field embedded,
// like ARM.
//
// A8.6.16 B
// Check for undefined encodings.
unsigned cond;
if (Name == "t2Bcc") {
if ((cond = slice(insn, 25, 22)) >= 14)
return false;
MI.addOperand(MCOperand::CreateImm(CondCode(cond)));
} else if (Name == "tBcc") {
if ((cond = slice(insn, 11, 8)) == 14)
return false;
MI.addOperand(MCOperand::CreateImm(CondCode(cond)));
} else
MI.addOperand(MCOperand::CreateImm(ARMCC::AL));
} else {
// ARM instructions get their condition field from Inst{31-28}.
// We should reject Inst{31-28} = 0b1111 as invalid encoding.
if (!isNEONDomain(TSFlags) && getCondField(insn) == 0xF)
return false;
MI.addOperand(MCOperand::CreateImm(CondCode(getCondField(insn))));
}
}
MI.addOperand(MCOperand::CreateReg(ARM::CPSR));
Idx += 2;
NumOpsRemaining -= 2;
}
if (NumOpsRemaining == 0)
return true;
// Next, if OptionalDefOperand exists, we check whether the 'S' bit is set.
if (OpInfo[Idx].isOptionalDef() && OpInfo[Idx].RegClass==ARM::CCRRegClassID) {
MI.addOperand(MCOperand::CreateReg(getSBit(insn) == 1 ? ARM::CPSR : 0));
--NumOpsRemaining;
}
if (NumOpsRemaining == 0)
return true;
else
return false;
}
/// RunBuildAfterHook - RunBuildAfterHook performs operations deemed necessary
/// after BuildIt is finished.
bool ARMBasicMCBuilder::RunBuildAfterHook(bool Status, MCInst &MI,
uint32_t insn) {
if (!SP) return Status;
if (Opcode == ARM::t2IT)
Status = SP->InitIT(slice(insn, 7, 0)) ? Status : false;
else if (InITBlock())
SP->UpdateIT();
return Status;
}
/// Opcode, Format, and NumOperands make up an ARM Basic MCBuilder.
ARMBasicMCBuilder::ARMBasicMCBuilder(unsigned opc, ARMFormat format,
unsigned short num)
: Opcode(opc), Format(format), NumOps(num), SP(0), Err(0) {
unsigned Idx = (unsigned)format;
assert(Idx < (array_lengthof(FuncPtrs) - 1) && "Unknown format");
Disasm = FuncPtrs[Idx];
}
/// CreateMCBuilder - Return an ARMBasicMCBuilder that can build up the MC
/// infrastructure of an MCInst given the Opcode and Format of the instr.
/// Return NULL if it fails to create/return a proper builder. API clients
/// are responsible for freeing up of the allocated memory. Cacheing can be
/// performed by the API clients to improve performance.
ARMBasicMCBuilder *llvm::CreateMCBuilder(unsigned Opcode, ARMFormat Format) {
// For "Unknown format", fail by returning a NULL pointer.
if ((unsigned)Format >= (array_lengthof(FuncPtrs) - 1)) {
DEBUG(errs() << "Unknown format\n");
return 0;
}
return new ARMBasicMCBuilder(Opcode, Format,
ARMInsts[Opcode].getNumOperands());
}
/// tryAddingSymbolicOperand - tryAddingSymbolicOperand trys to add a symbolic
/// operand in place of the immediate Value in the MCInst. The immediate
/// Value has had any PC adjustment made by the caller. If the getOpInfo()
/// function was set as part of the setupBuilderForSymbolicDisassembly() call
/// then that function is called to get any symbolic information at the
/// builder's Address for this instrution. If that returns non-zero then the
/// symbolic information it returns is used to create an MCExpr and that is
/// added as an operand to the MCInst. This function returns true if it adds
/// an operand to the MCInst and false otherwise.
bool ARMBasicMCBuilder::tryAddingSymbolicOperand(uint64_t Value,
uint64_t InstSize,
MCInst &MI) {
if (!GetOpInfo)
return false;
struct LLVMOpInfo1 SymbolicOp;
SymbolicOp.Value = Value;
if (!GetOpInfo(DisInfo, Address, 0 /* Offset */, InstSize, 1, &SymbolicOp))
return false;
const MCExpr *Add = NULL;
if (SymbolicOp.AddSymbol.Present) {
if (SymbolicOp.AddSymbol.Name) {
StringRef Name(SymbolicOp.AddSymbol.Name);
MCSymbol *Sym = Ctx->GetOrCreateSymbol(Name);
Add = MCSymbolRefExpr::Create(Sym, *Ctx);
} else {
Add = MCConstantExpr::Create(SymbolicOp.AddSymbol.Value, *Ctx);
}
}
const MCExpr *Sub = NULL;
if (SymbolicOp.SubtractSymbol.Present) {
if (SymbolicOp.SubtractSymbol.Name) {
StringRef Name(SymbolicOp.SubtractSymbol.Name);
MCSymbol *Sym = Ctx->GetOrCreateSymbol(Name);
Sub = MCSymbolRefExpr::Create(Sym, *Ctx);
} else {
Sub = MCConstantExpr::Create(SymbolicOp.SubtractSymbol.Value, *Ctx);
}
}
const MCExpr *Off = NULL;
if (SymbolicOp.Value != 0)
Off = MCConstantExpr::Create(SymbolicOp.Value, *Ctx);
const MCExpr *Expr;
if (Sub) {
const MCExpr *LHS;
if (Add)
LHS = MCBinaryExpr::CreateSub(Add, Sub, *Ctx);
else
LHS = MCUnaryExpr::CreateMinus(Sub, *Ctx);
if (Off != 0)
Expr = MCBinaryExpr::CreateAdd(LHS, Off, *Ctx);
else
Expr = LHS;
} else if (Add) {
if (Off != 0)
Expr = MCBinaryExpr::CreateAdd(Add, Off, *Ctx);
else
Expr = Add;
} else {
if (Off != 0)
Expr = Off;
else
Expr = MCConstantExpr::Create(0, *Ctx);
}
if (SymbolicOp.VariantKind == LLVMDisassembler_VariantKind_ARM_HI16)
MI.addOperand(MCOperand::CreateExpr(ARMMCExpr::CreateUpper16(Expr, *Ctx)));
else if (SymbolicOp.VariantKind == LLVMDisassembler_VariantKind_ARM_LO16)
MI.addOperand(MCOperand::CreateExpr(ARMMCExpr::CreateLower16(Expr, *Ctx)));
else if (SymbolicOp.VariantKind == LLVMDisassembler_VariantKind_None)
MI.addOperand(MCOperand::CreateExpr(Expr));
else
assert("bad SymbolicOp.VariantKind");
return true;
}