xref: /gem5/src/arch/alpha/isa_traits.hh

/*
 * Copyright (c) 2003-2005 The Regents of The University of Michigan
 * All rights reserved.
 *
 * 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.
 *
 * Authors: Steve Reinhardt
 *          Gabe Black
 */

#ifndef __ARCH_ALPHA_ISA_TRAITS_HH__
#define __ARCH_ALPHA_ISA_TRAITS_HH__

namespace LittleEndianGuest {}

#include "arch/alpha/types.hh"
#include "arch/alpha/constants.hh"
#include "arch/alpha/regfile.hh"
#include "config/full_system.hh"
#include "sim/host.hh"

class StaticInstPtr;

#if !FULL_SYSTEM
class SyscallReturn {
        public:
           template <class T>
           SyscallReturn(T v, bool s)
           {
               retval = (uint64_t)v;
               success = s;
           }

           template <class T>
           SyscallReturn(T v)
           {
               success = (v >= 0);
               retval = (uint64_t)v;
           }

           ~SyscallReturn() {}

           SyscallReturn& operator=(const SyscallReturn& s) {
               retval = s.retval;
               success = s.success;
               return *this;
           }

           bool successful() { return success; }
           uint64_t value() { return retval; }


       private:
           uint64_t retval;
           bool success;
};

#endif

#if FULL_SYSTEM
#include "arch/alpha/isa_fullsys_traits.hh"
#endif


namespace AlphaISA
{

using namespace LittleEndianGuest;

// redirected register map, really only used for the full system case.
extern const int reg_redir[NumIntRegs];

    StaticInstPtr decodeInst(ExtMachInst);

#if !FULL_SYSTEM
    static inline void setSyscallReturn(SyscallReturn return_value, RegFile *regs)
    {
        // check for error condition.  Alpha syscall convention is to
        // indicate success/failure in reg a3 (r19) and put the
        // return value itself in the standard return value reg (v0).
        if (return_value.successful()) {
            // no error
            regs->setIntReg(SyscallSuccessReg, 0);
            regs->setIntReg(ReturnValueReg, return_value.value());
        } else {
            // got an error, return details
            regs->setIntReg(SyscallSuccessReg, (IntReg)-1);
            regs->setIntReg(ReturnValueReg, -return_value.value());
        }
    }
#endif
};

#endif // __ARCH_ALPHA_ISA_TRAITS_HH__