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			458 lines
		
	
	
		
			19 KiB
		
	
	
	
		
			C++
		
	
	
	
			
		
		
	
	
			458 lines
		
	
	
		
			19 KiB
		
	
	
	
		
			C++
		
	
	
	
| //===-- SystemZDisassembler.cpp - Disassembler for SystemZ ------*- C++ -*-===//
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| //
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| //                     The LLVM Compiler Infrastructure
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| //
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| // This file is distributed under the University of Illinois Open Source
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| // License. See LICENSE.TXT for details.
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| //
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| //===----------------------------------------------------------------------===//
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| 
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| #include "MCTargetDesc/SystemZMCTargetDesc.h"
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| #include "SystemZ.h"
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| #include "llvm/MC/MCDisassembler/MCDisassembler.h"
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| #include "llvm/MC/MCFixedLenDisassembler.h"
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| #include "llvm/MC/MCInst.h"
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| #include "llvm/MC/MCSubtargetInfo.h"
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| #include "llvm/Support/MathExtras.h"
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| #include "llvm/Support/TargetRegistry.h"
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| #include <cassert>
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| #include <cstdint>
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| 
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| using namespace llvm;
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| 
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| #define DEBUG_TYPE "systemz-disassembler"
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| 
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| typedef MCDisassembler::DecodeStatus DecodeStatus;
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| 
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| namespace {
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| 
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| class SystemZDisassembler : public MCDisassembler {
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| public:
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|   SystemZDisassembler(const MCSubtargetInfo &STI, MCContext &Ctx)
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|     : MCDisassembler(STI, Ctx) {}
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|   ~SystemZDisassembler() override = default;
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| 
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|   DecodeStatus getInstruction(MCInst &instr, uint64_t &Size,
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|                               ArrayRef<uint8_t> Bytes, uint64_t Address,
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|                               raw_ostream &VStream,
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|                               raw_ostream &CStream) const override;
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| };
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| 
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| } // end anonymous namespace
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| 
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| static MCDisassembler *createSystemZDisassembler(const Target &T,
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|                                                  const MCSubtargetInfo &STI,
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|                                                  MCContext &Ctx) {
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|   return new SystemZDisassembler(STI, Ctx);
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| }
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| 
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| extern "C" void LLVMInitializeSystemZDisassembler() {
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|   // Register the disassembler.
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|   TargetRegistry::RegisterMCDisassembler(getTheSystemZTarget(),
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|                                          createSystemZDisassembler);
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| }
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| 
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| /// tryAddingSymbolicOperand - trys to add a symbolic operand in place of the
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| /// immediate Value in the MCInst.
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| ///
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| /// @param Value      - The immediate Value, has had any PC adjustment made by
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| ///                     the caller.
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| /// @param isBranch   - If the instruction is a branch instruction
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| /// @param Address    - The starting address of the instruction
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| /// @param Offset     - The byte offset to this immediate in the instruction
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| /// @param Width      - The byte width of this immediate in the instruction
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| ///
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| /// If the getOpInfo() function was set when setupForSymbolicDisassembly() was
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| /// called then that function is called to get any symbolic information for the
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| /// immediate in the instruction using the Address, Offset and Width.  If that
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| /// returns non-zero then the symbolic information it returns is used to create
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| /// an MCExpr and that is added as an operand to the MCInst.  If getOpInfo()
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| /// returns zero and isBranch is true then a symbol look up for immediate Value
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| /// is done and if a symbol is found an MCExpr is created with that, else
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| /// an MCExpr with the immediate Value is created.  This function returns true
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| /// if it adds an operand to the MCInst and false otherwise.
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| static bool tryAddingSymbolicOperand(int64_t Value, bool isBranch,
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|                                      uint64_t Address, uint64_t Offset,
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|                                      uint64_t Width, MCInst &MI,
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|                                      const void *Decoder) {
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|   const MCDisassembler *Dis = static_cast<const MCDisassembler*>(Decoder);
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|   return Dis->tryAddingSymbolicOperand(MI, Value, Address, isBranch,
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|                                        Offset, Width);
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| }
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| 
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| static DecodeStatus decodeRegisterClass(MCInst &Inst, uint64_t RegNo,
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|                                         const unsigned *Regs, unsigned Size) {
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|   assert(RegNo < Size && "Invalid register");
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|   RegNo = Regs[RegNo];
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|   if (RegNo == 0)
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|     return MCDisassembler::Fail;
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|   Inst.addOperand(MCOperand::createReg(RegNo));
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|   return MCDisassembler::Success;
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| }
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| 
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| static DecodeStatus DecodeGR32BitRegisterClass(MCInst &Inst, uint64_t RegNo,
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|                                                uint64_t Address,
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|                                                const void *Decoder) {
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|   return decodeRegisterClass(Inst, RegNo, SystemZMC::GR32Regs, 16);
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| }
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| 
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| static DecodeStatus DecodeGRH32BitRegisterClass(MCInst &Inst, uint64_t RegNo,
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|                                                 uint64_t Address,
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|                                                 const void *Decoder) {
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|   return decodeRegisterClass(Inst, RegNo, SystemZMC::GRH32Regs, 16);
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| }
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| 
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| static DecodeStatus DecodeGR64BitRegisterClass(MCInst &Inst, uint64_t RegNo,
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|                                                uint64_t Address,
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|                                                const void *Decoder) {
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|   return decodeRegisterClass(Inst, RegNo, SystemZMC::GR64Regs, 16);
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| }
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| 
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| static DecodeStatus DecodeGR128BitRegisterClass(MCInst &Inst, uint64_t RegNo,
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|                                                 uint64_t Address,
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|                                                 const void *Decoder) {
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|   return decodeRegisterClass(Inst, RegNo, SystemZMC::GR128Regs, 16);
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| }
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| 
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| static DecodeStatus DecodeADDR64BitRegisterClass(MCInst &Inst, uint64_t RegNo,
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|                                                  uint64_t Address,
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|                                                  const void *Decoder) {
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|   return decodeRegisterClass(Inst, RegNo, SystemZMC::GR64Regs, 16);
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| }
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| 
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| static DecodeStatus DecodeFP32BitRegisterClass(MCInst &Inst, uint64_t RegNo,
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|                                                uint64_t Address,
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|                                                const void *Decoder) {
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|   return decodeRegisterClass(Inst, RegNo, SystemZMC::FP32Regs, 16);
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| }
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| 
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| static DecodeStatus DecodeFP64BitRegisterClass(MCInst &Inst, uint64_t RegNo,
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|                                                uint64_t Address,
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|                                                const void *Decoder) {
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|   return decodeRegisterClass(Inst, RegNo, SystemZMC::FP64Regs, 16);
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| }
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| 
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| static DecodeStatus DecodeFP128BitRegisterClass(MCInst &Inst, uint64_t RegNo,
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|                                                 uint64_t Address,
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|                                                 const void *Decoder) {
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|   return decodeRegisterClass(Inst, RegNo, SystemZMC::FP128Regs, 16);
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| }
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| 
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| static DecodeStatus DecodeVR32BitRegisterClass(MCInst &Inst, uint64_t RegNo,
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|                                                uint64_t Address,
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|                                                const void *Decoder) {
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|   return decodeRegisterClass(Inst, RegNo, SystemZMC::VR32Regs, 32);
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| }
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| 
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| static DecodeStatus DecodeVR64BitRegisterClass(MCInst &Inst, uint64_t RegNo,
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|                                                uint64_t Address,
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|                                                const void *Decoder) {
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|   return decodeRegisterClass(Inst, RegNo, SystemZMC::VR64Regs, 32);
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| }
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| 
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| static DecodeStatus DecodeVR128BitRegisterClass(MCInst &Inst, uint64_t RegNo,
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|                                                 uint64_t Address,
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|                                                 const void *Decoder) {
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|   return decodeRegisterClass(Inst, RegNo, SystemZMC::VR128Regs, 32);
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| }
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| 
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| static DecodeStatus DecodeAR32BitRegisterClass(MCInst &Inst, uint64_t RegNo,
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|                                                uint64_t Address,
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|                                                const void *Decoder) {
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|   return decodeRegisterClass(Inst, RegNo, SystemZMC::AR32Regs, 16);
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| }
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| 
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| template<unsigned N>
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| static DecodeStatus decodeUImmOperand(MCInst &Inst, uint64_t Imm) {
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|   if (!isUInt<N>(Imm))
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|     return MCDisassembler::Fail;
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|   Inst.addOperand(MCOperand::createImm(Imm));
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|   return MCDisassembler::Success;
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| }
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| 
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| template<unsigned N>
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| static DecodeStatus decodeSImmOperand(MCInst &Inst, uint64_t Imm) {
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|   if (!isUInt<N>(Imm))
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|     return MCDisassembler::Fail;
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|   Inst.addOperand(MCOperand::createImm(SignExtend64<N>(Imm)));
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|   return MCDisassembler::Success;
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| }
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| 
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| static DecodeStatus decodeU1ImmOperand(MCInst &Inst, uint64_t Imm,
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|                                        uint64_t Address, const void *Decoder) {
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|   return decodeUImmOperand<1>(Inst, Imm);
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| }
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| 
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| static DecodeStatus decodeU2ImmOperand(MCInst &Inst, uint64_t Imm,
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|                                        uint64_t Address, const void *Decoder) {
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|   return decodeUImmOperand<2>(Inst, Imm);
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| }
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| 
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| static DecodeStatus decodeU3ImmOperand(MCInst &Inst, uint64_t Imm,
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|                                        uint64_t Address, const void *Decoder) {
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|   return decodeUImmOperand<3>(Inst, Imm);
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| }
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| 
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| static DecodeStatus decodeU4ImmOperand(MCInst &Inst, uint64_t Imm,
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|                                        uint64_t Address, const void *Decoder) {
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|   return decodeUImmOperand<4>(Inst, Imm);
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| }
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| 
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| static DecodeStatus decodeU6ImmOperand(MCInst &Inst, uint64_t Imm,
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|                                        uint64_t Address, const void *Decoder) {
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|   return decodeUImmOperand<6>(Inst, Imm);
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| }
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| 
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| static DecodeStatus decodeU8ImmOperand(MCInst &Inst, uint64_t Imm,
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|                                        uint64_t Address, const void *Decoder) {
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|   return decodeUImmOperand<8>(Inst, Imm);
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| }
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| 
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| static DecodeStatus decodeU12ImmOperand(MCInst &Inst, uint64_t Imm,
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|                                         uint64_t Address, const void *Decoder) {
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|   return decodeUImmOperand<12>(Inst, Imm);
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| }
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| 
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| static DecodeStatus decodeU16ImmOperand(MCInst &Inst, uint64_t Imm,
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|                                         uint64_t Address, const void *Decoder) {
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|   return decodeUImmOperand<16>(Inst, Imm);
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| }
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| 
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| static DecodeStatus decodeU32ImmOperand(MCInst &Inst, uint64_t Imm,
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|                                         uint64_t Address, const void *Decoder) {
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|   return decodeUImmOperand<32>(Inst, Imm);
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| }
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| 
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| static DecodeStatus decodeS8ImmOperand(MCInst &Inst, uint64_t Imm,
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|                                        uint64_t Address, const void *Decoder) {
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|   return decodeSImmOperand<8>(Inst, Imm);
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| }
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| 
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| static DecodeStatus decodeS16ImmOperand(MCInst &Inst, uint64_t Imm,
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|                                         uint64_t Address, const void *Decoder) {
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|   return decodeSImmOperand<16>(Inst, Imm);
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| }
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| 
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| static DecodeStatus decodeS32ImmOperand(MCInst &Inst, uint64_t Imm,
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|                                         uint64_t Address, const void *Decoder) {
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|   return decodeSImmOperand<32>(Inst, Imm);
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| }
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| 
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| template<unsigned N>
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| static DecodeStatus decodePCDBLOperand(MCInst &Inst, uint64_t Imm,
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|                                        uint64_t Address,
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|                                        bool isBranch,
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|                                        const void *Decoder) {
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|   assert(isUInt<N>(Imm) && "Invalid PC-relative offset");
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|   uint64_t Value = SignExtend64<N>(Imm) * 2 + Address;
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| 
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|   if (!tryAddingSymbolicOperand(Value, isBranch, Address, 2, N / 8,
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|                                 Inst, Decoder))
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|     Inst.addOperand(MCOperand::createImm(Value));
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| 
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|   return MCDisassembler::Success;
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| }
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| 
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| static DecodeStatus decodePC12DBLBranchOperand(MCInst &Inst, uint64_t Imm,
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|                                                uint64_t Address,
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|                                                const void *Decoder) {
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|   return decodePCDBLOperand<12>(Inst, Imm, Address, true, Decoder);
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| }
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| 
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| static DecodeStatus decodePC16DBLBranchOperand(MCInst &Inst, uint64_t Imm,
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|                                                uint64_t Address,
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|                                                const void *Decoder) {
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|   return decodePCDBLOperand<16>(Inst, Imm, Address, true, Decoder);
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| }
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| 
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| static DecodeStatus decodePC24DBLBranchOperand(MCInst &Inst, uint64_t Imm,
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|                                                uint64_t Address,
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|                                                const void *Decoder) {
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|   return decodePCDBLOperand<24>(Inst, Imm, Address, true, Decoder);
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| }
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| 
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| static DecodeStatus decodePC32DBLBranchOperand(MCInst &Inst, uint64_t Imm,
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|                                                uint64_t Address,
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|                                                const void *Decoder) {
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|   return decodePCDBLOperand<32>(Inst, Imm, Address, true, Decoder);
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| }
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| 
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| static DecodeStatus decodePC32DBLOperand(MCInst &Inst, uint64_t Imm,
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|                                          uint64_t Address,
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|                                          const void *Decoder) {
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|   return decodePCDBLOperand<32>(Inst, Imm, Address, false, Decoder);
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| }
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| 
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| static DecodeStatus decodeBDAddr12Operand(MCInst &Inst, uint64_t Field,
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|                                           const unsigned *Regs) {
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|   uint64_t Base = Field >> 12;
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|   uint64_t Disp = Field & 0xfff;
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|   assert(Base < 16 && "Invalid BDAddr12");
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|   Inst.addOperand(MCOperand::createReg(Base == 0 ? 0 : Regs[Base]));
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|   Inst.addOperand(MCOperand::createImm(Disp));
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|   return MCDisassembler::Success;
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| }
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| 
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| static DecodeStatus decodeBDAddr20Operand(MCInst &Inst, uint64_t Field,
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|                                           const unsigned *Regs) {
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|   uint64_t Base = Field >> 20;
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|   uint64_t Disp = ((Field << 12) & 0xff000) | ((Field >> 8) & 0xfff);
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|   assert(Base < 16 && "Invalid BDAddr20");
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|   Inst.addOperand(MCOperand::createReg(Base == 0 ? 0 : Regs[Base]));
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|   Inst.addOperand(MCOperand::createImm(SignExtend64<20>(Disp)));
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|   return MCDisassembler::Success;
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| }
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| 
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| static DecodeStatus decodeBDXAddr12Operand(MCInst &Inst, uint64_t Field,
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|                                            const unsigned *Regs) {
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|   uint64_t Index = Field >> 16;
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|   uint64_t Base = (Field >> 12) & 0xf;
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|   uint64_t Disp = Field & 0xfff;
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|   assert(Index < 16 && "Invalid BDXAddr12");
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|   Inst.addOperand(MCOperand::createReg(Base == 0 ? 0 : Regs[Base]));
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|   Inst.addOperand(MCOperand::createImm(Disp));
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|   Inst.addOperand(MCOperand::createReg(Index == 0 ? 0 : Regs[Index]));
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|   return MCDisassembler::Success;
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| }
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| 
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| static DecodeStatus decodeBDXAddr20Operand(MCInst &Inst, uint64_t Field,
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|                                            const unsigned *Regs) {
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|   uint64_t Index = Field >> 24;
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|   uint64_t Base = (Field >> 20) & 0xf;
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|   uint64_t Disp = ((Field & 0xfff00) >> 8) | ((Field & 0xff) << 12);
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|   assert(Index < 16 && "Invalid BDXAddr20");
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|   Inst.addOperand(MCOperand::createReg(Base == 0 ? 0 : Regs[Base]));
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|   Inst.addOperand(MCOperand::createImm(SignExtend64<20>(Disp)));
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|   Inst.addOperand(MCOperand::createReg(Index == 0 ? 0 : Regs[Index]));
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|   return MCDisassembler::Success;
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| }
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| 
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| static DecodeStatus decodeBDLAddr12Len8Operand(MCInst &Inst, uint64_t Field,
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|                                                const unsigned *Regs) {
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|   uint64_t Length = Field >> 16;
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|   uint64_t Base = (Field >> 12) & 0xf;
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|   uint64_t Disp = Field & 0xfff;
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|   assert(Length < 256 && "Invalid BDLAddr12Len8");
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|   Inst.addOperand(MCOperand::createReg(Base == 0 ? 0 : Regs[Base]));
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|   Inst.addOperand(MCOperand::createImm(Disp));
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|   Inst.addOperand(MCOperand::createImm(Length + 1));
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|   return MCDisassembler::Success;
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| }
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| 
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| static DecodeStatus decodeBDRAddr12Operand(MCInst &Inst, uint64_t Field,
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|                                            const unsigned *Regs) {
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|   uint64_t Length = Field >> 16;
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|   uint64_t Base = (Field >> 12) & 0xf;
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|   uint64_t Disp = Field & 0xfff;
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|   assert(Length < 16 && "Invalid BDRAddr12");
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|   Inst.addOperand(MCOperand::createReg(Base == 0 ? 0 : Regs[Base]));
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|   Inst.addOperand(MCOperand::createImm(Disp));
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|   Inst.addOperand(MCOperand::createReg(Regs[Length]));
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|   return MCDisassembler::Success;
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| }
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| 
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| static DecodeStatus decodeBDVAddr12Operand(MCInst &Inst, uint64_t Field,
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|                                            const unsigned *Regs) {
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|   uint64_t Index = Field >> 16;
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|   uint64_t Base = (Field >> 12) & 0xf;
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|   uint64_t Disp = Field & 0xfff;
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|   assert(Index < 32 && "Invalid BDVAddr12");
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|   Inst.addOperand(MCOperand::createReg(Base == 0 ? 0 : Regs[Base]));
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|   Inst.addOperand(MCOperand::createImm(Disp));
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|   Inst.addOperand(MCOperand::createReg(SystemZMC::VR128Regs[Index]));
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|   return MCDisassembler::Success;
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| }
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| 
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| static DecodeStatus decodeBDAddr32Disp12Operand(MCInst &Inst, uint64_t Field,
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|                                                 uint64_t Address,
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|                                                 const void *Decoder) {
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|   return decodeBDAddr12Operand(Inst, Field, SystemZMC::GR32Regs);
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| }
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| 
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| static DecodeStatus decodeBDAddr32Disp20Operand(MCInst &Inst, uint64_t Field,
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|                                                 uint64_t Address,
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|                                                 const void *Decoder) {
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|   return decodeBDAddr20Operand(Inst, Field, SystemZMC::GR32Regs);
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| }
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| 
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| static DecodeStatus decodeBDAddr64Disp12Operand(MCInst &Inst, uint64_t Field,
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|                                                 uint64_t Address,
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|                                                 const void *Decoder) {
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|   return decodeBDAddr12Operand(Inst, Field, SystemZMC::GR64Regs);
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| }
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| 
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| static DecodeStatus decodeBDAddr64Disp20Operand(MCInst &Inst, uint64_t Field,
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|                                                 uint64_t Address,
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|                                                 const void *Decoder) {
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|   return decodeBDAddr20Operand(Inst, Field, SystemZMC::GR64Regs);
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| }
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| 
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| static DecodeStatus decodeBDXAddr64Disp12Operand(MCInst &Inst, uint64_t Field,
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|                                                  uint64_t Address,
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|                                                  const void *Decoder) {
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|   return decodeBDXAddr12Operand(Inst, Field, SystemZMC::GR64Regs);
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| }
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| 
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| static DecodeStatus decodeBDXAddr64Disp20Operand(MCInst &Inst, uint64_t Field,
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|                                                  uint64_t Address,
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|                                                  const void *Decoder) {
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|   return decodeBDXAddr20Operand(Inst, Field, SystemZMC::GR64Regs);
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| }
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| 
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| static DecodeStatus decodeBDLAddr64Disp12Len8Operand(MCInst &Inst,
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|                                                      uint64_t Field,
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|                                                      uint64_t Address,
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|                                                      const void *Decoder) {
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|   return decodeBDLAddr12Len8Operand(Inst, Field, SystemZMC::GR64Regs);
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| }
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| 
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| static DecodeStatus decodeBDRAddr64Disp12Operand(MCInst &Inst,
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|                                                  uint64_t Field,
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|                                                  uint64_t Address,
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|                                                  const void *Decoder) {
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|   return decodeBDRAddr12Operand(Inst, Field, SystemZMC::GR64Regs);
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| }
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| 
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| static DecodeStatus decodeBDVAddr64Disp12Operand(MCInst &Inst, uint64_t Field,
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|                                                  uint64_t Address,
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|                                                  const void *Decoder) {
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|   return decodeBDVAddr12Operand(Inst, Field, SystemZMC::GR64Regs);
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| }
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| 
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| #include "SystemZGenDisassemblerTables.inc"
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| 
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| DecodeStatus SystemZDisassembler::getInstruction(MCInst &MI, uint64_t &Size,
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|                                                  ArrayRef<uint8_t> Bytes,
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|                                                  uint64_t Address,
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|                                                  raw_ostream &OS,
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|                                                  raw_ostream &CS) const {
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|   // Get the first two bytes of the instruction.
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|   Size = 0;
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|   if (Bytes.size() < 2)
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|     return MCDisassembler::Fail;
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| 
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|   // The top 2 bits of the first byte specify the size.
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|   const uint8_t *Table;
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|   if (Bytes[0] < 0x40) {
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|     Size = 2;
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|     Table = DecoderTable16;
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|   } else if (Bytes[0] < 0xc0) {
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|     Size = 4;
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|     Table = DecoderTable32;
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|   } else {
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|     Size = 6;
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|     Table = DecoderTable48;
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|   }
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| 
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|   // Read any remaining bytes.
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|   if (Bytes.size() < Size)
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|     return MCDisassembler::Fail;
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| 
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|   // Construct the instruction.
 | |
|   uint64_t Inst = 0;
 | |
|   for (uint64_t I = 0; I < Size; ++I)
 | |
|     Inst = (Inst << 8) | Bytes[I];
 | |
| 
 | |
|   return decodeInstruction(Table, MI, Inst, Address, this, STI);
 | |
| }
 |