ras.hh

来自「linux下基于c++的处理器仿真平台。具有处理器流水线」· HH 代码 · 共 72 行

/*
 * Copyright (c) 2004, 2005
 * The Regents of The University of Michigan
 * All Rights Reserved
 *
 * This code is part of the M5 simulator, developed by Nathan Binkert,
 * Erik Hallnor, Steve Raasch, and Steve Reinhardt, with contributions
 * from Ron Dreslinski, Dave Greene, Lisa Hsu, Kevin Lim, Ali Saidi, 
 * and Andrew Schultz.
 *
 * Permission is granted to use, copy, create derivative works and
 * redistribute this software and such derivative works for any
 * purpose, so long as the copyright notice above, this grant of
 * permission, and the disclaimer below appear in all copies made; and
 * so long as the name of The University of Michigan is not used in
 * any advertising or publicity pertaining to the use or distribution
 * of this software without specific, written prior authorization.
 *
 * THIS SOFTWARE IS PROVIDED AS IS, WITHOUT REPRESENTATION FROM THE
 * UNIVERSITY OF MICHIGAN AS TO ITS FITNESS FOR ANY PURPOSE, AND
 * WITHOUT WARRANTY BY THE UNIVERSITY OF MICHIGAN OF ANY KIND, EITHER
 * EXPRESS OR IMPLIED, INCLUDING WITHOUT LIMITATION THE IMPLIED
 * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
 * PURPOSE. THE REGENTS OF THE UNIVERSITY OF MICHIGAN SHALL NOT BE
 * LIABLE FOR ANY DAMAGES, INCLUDING DIRECT, SPECIAL, INDIRECT,
 * INCIDENTAL, OR CONSEQUENTIAL DAMAGES, WITH RESPECT TO ANY CLAIM
 * ARISING OUT OF OR IN CONNECTION WITH THE USE OF THE SOFTWARE, EVEN
 * IF IT HAS BEEN OR IS HEREAFTER ADVISED OF THE POSSIBILITY OF SUCH
 * DAMAGES.
 */

#ifndef __CPU_O3_CPU_RAS_HH__
#define __CPU_O3_CPU_RAS_HH__

// For Addr type.
#include "arch/alpha/isa_traits.hh"

class ReturnAddrStack
{
  public:
    ReturnAddrStack(unsigned numEntries);

    Addr top()
    { return addrStack[tos]; }

    unsigned topIdx()
    { return tos; }

    void push(const Addr &return_addr);

    void pop();

    void restore(unsigned top_entry_idx, const Addr &restored_target);

  private:
    inline void incrTos()
    { if (++tos == numEntries) tos = 0; }

    inline void decrTos()
    { tos = (tos == 0 ? numEntries - 1 : tos - 1); }

    Addr *addrStack;

    unsigned numEntries;

    unsigned usedEntries;

    unsigned tos;
};

#endif // __CPU_O3_CPU_RAS_HH__