src/arch/arm/insts/misc.cc - public/gem5 - Git at Google

 /*
  * Copyright (c) 2010, 2012-2013, 2017-2018 ARM Limited
  * Copyright (c) 2013 Advanced Micro Devices, Inc.
  * All rights reserved
  *
  * The license below extends only to copyright in the software and shall
  * not be construed as granting a license to any other intellectual
  * property including but not limited to intellectual property relating
  * to a hardware implementation of the functionality of the software
  * licensed hereunder.  You may use the software subject to the license
  * terms below provided that you ensure that this notice is replicated
  * unmodified and in its entirety in all distributions of the software,
  * modified or unmodified, in source code or in binary form.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions are
  * met: redistributions of source code must retain the above copyright
  * notice, this list of conditions and the following disclaimer;
  * redistributions in binary form must reproduce the above copyright
  * notice, this list of conditions and the following disclaimer in the
  * documentation and/or other materials provided with the distribution;
  * neither the name of the copyright holders nor the names of its
  * contributors may be used to endorse or promote products derived from
  * this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */

 #include "arch/arm/insts/misc.hh"

 #include "cpu/reg_class.hh"

 namespace gem5
 {

 using namespace ArmISA;

 std::string
 MrsOp::generateDisassembly(Addr pc, const loader::SymbolTable *symtab) const
 {
     std::stringstream ss;
     printMnemonic(ss);
     printIntReg(ss, dest);
     ss << ", ";
     bool foundPsr = false;
     for (unsigned i = 0; i < numSrcRegs(); i++) {
         const RegId& reg = srcRegIdx(i);
         if (!reg.is(MiscRegClass)) {
             continue;
         }
         if (reg.index() == MISCREG_CPSR) {
             ss << "cpsr";
             foundPsr = true;
             break;
         }
         if (reg.index() == MISCREG_SPSR) {
             ss << "spsr";
             foundPsr = true;
             break;
         }
     }
     if (!foundPsr) {
         ss << "????";
     }
     return ss.str();
 }

 void
 MsrBase::printMsrBase(std::ostream &os) const
 {
     printMnemonic(os);
     bool apsr = false;
     bool foundPsr = false;
     for (unsigned i = 0; i < numDestRegs(); i++) {
         const RegId& reg = destRegIdx(i);
         if (!reg.is(MiscRegClass)) {
             continue;
         }
         if (reg.index() == MISCREG_CPSR) {
             os << "cpsr_";
             foundPsr = true;
             break;
         }
         if (reg.index() == MISCREG_SPSR) {
             if (bits(byteMask, 1, 0)) {
                 os << "spsr_";
             } else {
                 os << "apsr_";
                 apsr = true;
             }
             foundPsr = true;
             break;
         }
     }
     if (!foundPsr) {
         os << "????";
         return;
     }
     if (bits(byteMask, 3)) {
         if (apsr) {
             os << "nzcvq";
         } else {
             os << "f";
         }
     }
     if (bits(byteMask, 2)) {
         if (apsr) {
             os << "g";
         } else {
             os << "s";
         }
     }
     if (bits(byteMask, 1)) {
         os << "x";
     }
     if (bits(byteMask, 0)) {
         os << "c";
     }
 }

 std::string
 MsrImmOp::generateDisassembly(Addr pc, const loader::SymbolTable *symtab) const
 {
     std::stringstream ss;
     printMsrBase(ss);
     ccprintf(ss, ", #%#x", imm);
     return ss.str();
 }

 std::string
 MsrRegOp::generateDisassembly(Addr pc, const loader::SymbolTable *symtab) const
 {
     std::stringstream ss;
     printMsrBase(ss);
     ss << ", ";
     printIntReg(ss, op1);
     return ss.str();
 }

 std::string
 MrrcOp::generateDisassembly(Addr pc, const loader::SymbolTable *symtab) const
 {
     std::stringstream ss;
     printMnemonic(ss);
     printIntReg(ss, dest);
     ss << ", ";
     printIntReg(ss, dest2);
     ss << ", ";
     printMiscReg(ss, op1);
     return ss.str();
 }

 std::string
 McrrOp::generateDisassembly(Addr pc, const loader::SymbolTable *symtab) const
 {
     std::stringstream ss;
     printMnemonic(ss);
     printMiscReg(ss, dest);
     ss << ", ";
     printIntReg(ss, op1);
     ss << ", ";
     printIntReg(ss, op2);
     return ss.str();
 }

 std::string
 ImmOp::generateDisassembly(Addr pc, const loader::SymbolTable *symtab) const
 {
     std::stringstream ss;
     printMnemonic(ss);
     ccprintf(ss, "#%d", imm);
     return ss.str();
 }

 std::string
 RegImmOp::generateDisassembly(Addr pc, const loader::SymbolTable *symtab) const
 {
     std::stringstream ss;
     printMnemonic(ss);
     printIntReg(ss, dest);
     ccprintf(ss, ", #%d", imm);
     return ss.str();
 }

 std::string
 RegRegOp::generateDisassembly(Addr pc, const loader::SymbolTable *symtab) const
 {
     std::stringstream ss;
     printMnemonic(ss);
     printIntReg(ss, dest);
     ss << ", ";
     printIntReg(ss, op1);
     return ss.str();
 }

 std::string
 RegOp::generateDisassembly(Addr pc, const loader::SymbolTable *symtab) const
 {
     std::stringstream ss;
     printMnemonic(ss);
     printIntReg(ss, dest);
     return ss.str();
 }

 std::string
 RegRegRegImmOp::generateDisassembly(
         Addr pc, const loader::SymbolTable *symtab) const
 {
     std::stringstream ss;
     printMnemonic(ss);
     printIntReg(ss, dest);
     ss << ", ";
     printIntReg(ss, op1);
     ss << ", ";
     printIntReg(ss, op2);
     ccprintf(ss, ", #%d", imm);
     return ss.str();
 }

 std::string
 RegRegRegRegOp::generateDisassembly(
         Addr pc, const loader::SymbolTable *symtab) const
 {
     std::stringstream ss;
     printMnemonic(ss);
     printIntReg(ss, dest);
     ss << ", ";
     printIntReg(ss, op1);
     ss << ", ";
     printIntReg(ss, op2);
     ss << ", ";
     printIntReg(ss, op3);
     return ss.str();
 }

 std::string
 RegRegRegOp::generateDisassembly(
         Addr pc, const loader::SymbolTable *symtab) const
 {
     std::stringstream ss;
     printMnemonic(ss);
     printIntReg(ss, dest);
     ss << ", ";
     printIntReg(ss, op1);
     ss << ", ";
     printIntReg(ss, op2);
     return ss.str();
 }

 std::string
 RegRegImmOp::generateDisassembly(
         Addr pc, const loader::SymbolTable *symtab) const
 {
     std::stringstream ss;
     printMnemonic(ss);
     printIntReg(ss, dest);
     ss << ", ";
     printIntReg(ss, op1);
     ccprintf(ss, ", #%d", imm);
     return ss.str();
 }

 std::string
 MiscRegRegImmOp::generateDisassembly(
         Addr pc, const loader::SymbolTable *symtab) const
 {
     std::stringstream ss;
     printMnemonic(ss);
     printMiscReg(ss, dest);
     ss << ", ";
     printIntReg(ss, op1);
     return ss.str();
 }

 std::string
 RegMiscRegImmOp::generateDisassembly(
         Addr pc, const loader::SymbolTable *symtab) const
 {
     std::stringstream ss;
     printMnemonic(ss);
     printIntReg(ss, dest);
     ss << ", ";
     printMiscReg(ss, op1);
     return ss.str();
 }

 std::string
 RegImmImmOp::generateDisassembly(
         Addr pc, const loader::SymbolTable *symtab) const
 {
     std::stringstream ss;
     printMnemonic(ss);
     printIntReg(ss, dest);
     ccprintf(ss, ", #%d, #%d", imm1, imm2);
     return ss.str();
 }

 std::string
 RegRegImmImmOp::generateDisassembly(
         Addr pc, const loader::SymbolTable *symtab) const
 {
     std::stringstream ss;
     printMnemonic(ss);
     printIntReg(ss, dest);
     ss << ", ";
     printIntReg(ss, op1);
     ccprintf(ss, ", #%d, #%d", imm1, imm2);
     return ss.str();
 }

 std::string
 RegImmRegOp::generateDisassembly(
         Addr pc, const loader::SymbolTable *symtab) const
 {
     std::stringstream ss;
     printMnemonic(ss);
     printIntReg(ss, dest);
     ccprintf(ss, ", #%d, ", imm);
     printIntReg(ss, op1);
     return ss.str();
 }

 std::string
 RegImmRegShiftOp::generateDisassembly(
         Addr pc, const loader::SymbolTable *symtab) const
 {
     std::stringstream ss;
     printMnemonic(ss);
     printIntReg(ss, dest);
     ccprintf(ss, ", #%d, ", imm);
     printShiftOperand(ss, op1, true, shiftAmt, INTREG_ZERO, shiftType);
     printIntReg(ss, op1);
     return ss.str();
 }

 std::string
 UnknownOp::generateDisassembly(
         Addr pc, const loader::SymbolTable *symtab) const
 {
     return csprintf("%-10s (inst %#08x)", "unknown", encoding());
 }

 McrMrcMiscInst::McrMrcMiscInst(const char *_mnemonic, ExtMachInst _machInst,
                                uint64_t _iss, MiscRegIndex _miscReg)
     : ArmStaticInst(_mnemonic, _machInst, No_OpClass)
 {
     flags[IsNonSpeculative] = true;
     iss = _iss;
     miscReg = _miscReg;
 }

 Fault
 McrMrcMiscInst::execute(ExecContext *xc, Trace::InstRecord *traceData) const
 {
     bool hypTrap = mcrMrc15TrapToHyp(miscReg, xc->tcBase(), iss);

     if (hypTrap) {
         return std::make_shared<HypervisorTrap>(machInst, iss,
                                                 EC_TRAPPED_CP15_MCR_MRC);
     } else {
         return NoFault;
     }
 }

 std::string
 McrMrcMiscInst::generateDisassembly(
         Addr pc, const loader::SymbolTable *symtab) const
 {
     return csprintf("%-10s (pipe flush)", mnemonic);
 }

 McrMrcImplDefined::McrMrcImplDefined(const char *_mnemonic,
                                      ExtMachInst _machInst, uint64_t _iss,
                                      MiscRegIndex _miscReg)
     : McrMrcMiscInst(_mnemonic, _machInst, _iss, _miscReg)
 {}

 Fault
 McrMrcImplDefined::execute(ExecContext *xc, Trace::InstRecord *traceData) const
 {
     bool hypTrap = mcrMrc15TrapToHyp(miscReg, xc->tcBase(), iss);

     if (hypTrap) {
         return std::make_shared<HypervisorTrap>(machInst, iss,
                                                 EC_TRAPPED_CP15_MCR_MRC);
     } else {
         return std::make_shared<UndefinedInstruction>(machInst, false,
                                                       mnemonic);
     }
 }

 std::string
 McrMrcImplDefined::generateDisassembly(
         Addr pc, const loader::SymbolTable *symtab) const
 {
     return csprintf("%-10s (implementation defined)", mnemonic);
 }

 } // namespace gem5
	/*
	* Copyright (c) 2010, 2012-2013, 2017-2018 ARM Limited
	* Copyright (c) 2013 Advanced Micro Devices, Inc.
	* All rights reserved
	*
	* The license below extends only to copyright in the software and shall
	* not be construed as granting a license to any other intellectual
	* property including but not limited to intellectual property relating
	* to a hardware implementation of the functionality of the software
	* licensed hereunder. You may use the software subject to the license
	* terms below provided that you ensure that this notice is replicated
	* unmodified and in its entirety in all distributions of the software,
	* modified or unmodified, in source code or in binary form.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions are
	* met: redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer;
	* redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution;
	* neither the name of the copyright holders nor the names of its
	* contributors may be used to endorse or promote products derived from
	* this software without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
	* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
	* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
	* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
	* OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
	* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
	* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
	* OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*/

	#include "arch/arm/insts/misc.hh"

	#include "cpu/reg_class.hh"

	namespace gem5
	{

	using namespace ArmISA;

	std::string
	MrsOp::generateDisassembly(Addr pc, const loader::SymbolTable *symtab) const
	{
	std::stringstream ss;
	printMnemonic(ss);
	printIntReg(ss, dest);
	ss << ", ";
	bool foundPsr = false;
	for (unsigned i = 0; i < numSrcRegs(); i++) {
	const RegId& reg = srcRegIdx(i);
	if (!reg.is(MiscRegClass)) {
	continue;
	}
	if (reg.index() == MISCREG_CPSR) {
	ss << "cpsr";
	foundPsr = true;
	break;
	}
	if (reg.index() == MISCREG_SPSR) {
	ss << "spsr";
	foundPsr = true;
	break;
	}
	}
	if (!foundPsr) {
	ss << "????";
	}
	return ss.str();
	}

	void
	MsrBase::printMsrBase(std::ostream &os) const
	{
	printMnemonic(os);
	bool apsr = false;
	bool foundPsr = false;
	for (unsigned i = 0; i < numDestRegs(); i++) {
	const RegId& reg = destRegIdx(i);
	if (!reg.is(MiscRegClass)) {
	continue;
	}
	if (reg.index() == MISCREG_CPSR) {
	os << "cpsr_";
	foundPsr = true;
	break;
	}
	if (reg.index() == MISCREG_SPSR) {
	if (bits(byteMask, 1, 0)) {
	os << "spsr_";
	} else {
	os << "apsr_";
	apsr = true;
	}
	foundPsr = true;
	break;
	}
	}
	if (!foundPsr) {
	os << "????";
	return;
	}
	if (bits(byteMask, 3)) {
	if (apsr) {
	os << "nzcvq";
	} else {
	os << "f";
	}
	}
	if (bits(byteMask, 2)) {
	if (apsr) {
	os << "g";
	} else {
	os << "s";
	}
	}
	if (bits(byteMask, 1)) {
	os << "x";
	}
	if (bits(byteMask, 0)) {
	os << "c";
	}
	}

	std::string
	MsrImmOp::generateDisassembly(Addr pc, const loader::SymbolTable *symtab) const
	{
	std::stringstream ss;
	printMsrBase(ss);
	ccprintf(ss, ", #%#x", imm);
	return ss.str();
	}

	std::string
	MsrRegOp::generateDisassembly(Addr pc, const loader::SymbolTable *symtab) const
	{
	std::stringstream ss;
	printMsrBase(ss);
	ss << ", ";
	printIntReg(ss, op1);
	return ss.str();
	}

	std::string
	MrrcOp::generateDisassembly(Addr pc, const loader::SymbolTable *symtab) const
	{
	std::stringstream ss;
	printMnemonic(ss);
	printIntReg(ss, dest);
	ss << ", ";
	printIntReg(ss, dest2);
	ss << ", ";
	printMiscReg(ss, op1);
	return ss.str();
	}

	std::string
	McrrOp::generateDisassembly(Addr pc, const loader::SymbolTable *symtab) const
	{
	std::stringstream ss;
	printMnemonic(ss);
	printMiscReg(ss, dest);
	ss << ", ";
	printIntReg(ss, op1);
	ss << ", ";
	printIntReg(ss, op2);
	return ss.str();
	}

	std::string
	ImmOp::generateDisassembly(Addr pc, const loader::SymbolTable *symtab) const
	{
	std::stringstream ss;
	printMnemonic(ss);
	ccprintf(ss, "#%d", imm);
	return ss.str();
	}

	std::string
	RegImmOp::generateDisassembly(Addr pc, const loader::SymbolTable *symtab) const
	{
	std::stringstream ss;
	printMnemonic(ss);
	printIntReg(ss, dest);
	ccprintf(ss, ", #%d", imm);
	return ss.str();
	}

	std::string
	RegRegOp::generateDisassembly(Addr pc, const loader::SymbolTable *symtab) const
	{
	std::stringstream ss;
	printMnemonic(ss);
	printIntReg(ss, dest);
	ss << ", ";
	printIntReg(ss, op1);
	return ss.str();
	}

	std::string
	RegOp::generateDisassembly(Addr pc, const loader::SymbolTable *symtab) const
	{
	std::stringstream ss;
	printMnemonic(ss);
	printIntReg(ss, dest);
	return ss.str();
	}

	std::string
	RegRegRegImmOp::generateDisassembly(
	Addr pc, const loader::SymbolTable *symtab) const
	{
	std::stringstream ss;
	printMnemonic(ss);
	printIntReg(ss, dest);
	ss << ", ";
	printIntReg(ss, op1);
	ss << ", ";
	printIntReg(ss, op2);
	ccprintf(ss, ", #%d", imm);
	return ss.str();
	}

	std::string
	RegRegRegRegOp::generateDisassembly(
	Addr pc, const loader::SymbolTable *symtab) const
	{
	std::stringstream ss;
	printMnemonic(ss);
	printIntReg(ss, dest);
	ss << ", ";
	printIntReg(ss, op1);
	ss << ", ";
	printIntReg(ss, op2);
	ss << ", ";
	printIntReg(ss, op3);
	return ss.str();
	}

	std::string
	RegRegRegOp::generateDisassembly(
	Addr pc, const loader::SymbolTable *symtab) const
	{
	std::stringstream ss;
	printMnemonic(ss);
	printIntReg(ss, dest);
	ss << ", ";
	printIntReg(ss, op1);
	ss << ", ";
	printIntReg(ss, op2);
	return ss.str();
	}

	std::string
	RegRegImmOp::generateDisassembly(
	Addr pc, const loader::SymbolTable *symtab) const
	{
	std::stringstream ss;
	printMnemonic(ss);
	printIntReg(ss, dest);
	ss << ", ";
	printIntReg(ss, op1);
	ccprintf(ss, ", #%d", imm);
	return ss.str();
	}

	std::string
	MiscRegRegImmOp::generateDisassembly(
	Addr pc, const loader::SymbolTable *symtab) const
	{
	std::stringstream ss;
	printMnemonic(ss);
	printMiscReg(ss, dest);
	ss << ", ";
	printIntReg(ss, op1);
	return ss.str();
	}

	std::string
	RegMiscRegImmOp::generateDisassembly(
	Addr pc, const loader::SymbolTable *symtab) const
	{
	std::stringstream ss;
	printMnemonic(ss);
	printIntReg(ss, dest);
	ss << ", ";
	printMiscReg(ss, op1);
	return ss.str();
	}

	std::string
	RegImmImmOp::generateDisassembly(
	Addr pc, const loader::SymbolTable *symtab) const
	{
	std::stringstream ss;
	printMnemonic(ss);
	printIntReg(ss, dest);
	ccprintf(ss, ", #%d, #%d", imm1, imm2);
	return ss.str();
	}

	std::string
	RegRegImmImmOp::generateDisassembly(
	Addr pc, const loader::SymbolTable *symtab) const
	{
	std::stringstream ss;
	printMnemonic(ss);
	printIntReg(ss, dest);
	ss << ", ";
	printIntReg(ss, op1);
	ccprintf(ss, ", #%d, #%d", imm1, imm2);
	return ss.str();
	}

	std::string
	RegImmRegOp::generateDisassembly(
	Addr pc, const loader::SymbolTable *symtab) const
	{
	std::stringstream ss;
	printMnemonic(ss);
	printIntReg(ss, dest);
	ccprintf(ss, ", #%d, ", imm);
	printIntReg(ss, op1);
	return ss.str();
	}

	std::string
	RegImmRegShiftOp::generateDisassembly(
	Addr pc, const loader::SymbolTable *symtab) const
	{
	std::stringstream ss;
	printMnemonic(ss);
	printIntReg(ss, dest);
	ccprintf(ss, ", #%d, ", imm);
	printShiftOperand(ss, op1, true, shiftAmt, INTREG_ZERO, shiftType);
	printIntReg(ss, op1);
	return ss.str();
	}

	std::string
	UnknownOp::generateDisassembly(
	Addr pc, const loader::SymbolTable *symtab) const
	{
	return csprintf("%-10s (inst %#08x)", "unknown", encoding());
	}

	McrMrcMiscInst::McrMrcMiscInst(const char *_mnemonic, ExtMachInst _machInst,
	uint64_t _iss, MiscRegIndex _miscReg)
	: ArmStaticInst(_mnemonic, _machInst, No_OpClass)
	{
	flags[IsNonSpeculative] = true;
	iss = _iss;
	miscReg = _miscReg;
	}

	Fault
	McrMrcMiscInst::execute(ExecContext xc, Trace::InstRecord traceData) const
	{
	bool hypTrap = mcrMrc15TrapToHyp(miscReg, xc->tcBase(), iss);

	if (hypTrap) {
	return std::make_shared<HypervisorTrap>(machInst, iss,
	EC_TRAPPED_CP15_MCR_MRC);
	} else {
	return NoFault;
	}
	}

	std::string
	McrMrcMiscInst::generateDisassembly(
	Addr pc, const loader::SymbolTable *symtab) const
	{
	return csprintf("%-10s (pipe flush)", mnemonic);
	}

	McrMrcImplDefined::McrMrcImplDefined(const char *_mnemonic,
	ExtMachInst _machInst, uint64_t _iss,
	MiscRegIndex _miscReg)
	: McrMrcMiscInst(_mnemonic, _machInst, _iss, _miscReg)
	{}

	Fault
	McrMrcImplDefined::execute(ExecContext xc, Trace::InstRecord traceData) const
	{
	bool hypTrap = mcrMrc15TrapToHyp(miscReg, xc->tcBase(), iss);

	if (hypTrap) {
	return std::make_shared<HypervisorTrap>(machInst, iss,
	EC_TRAPPED_CP15_MCR_MRC);
	} else {
	return std::make_shared<UndefinedInstruction>(machInst, false,
	mnemonic);
	}
	}

	std::string
	McrMrcImplDefined::generateDisassembly(
	Addr pc, const loader::SymbolTable *symtab) const
	{
	return csprintf("%-10s (implementation defined)", mnemonic);
	}

	} // namespace gem5