src/cpu/o3/ras.cc

   1 /*
   2  * Copyright (c) 2004-2005 The Regents of The University of Michigan
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions are
   7  * met: redistributions of source code must retain the above copyright
   8  * notice, this list of conditions and the following disclaimer;
   9  * redistributions in binary form must reproduce the above copyright
  10  * notice, this list of conditions and the following disclaimer in the
  11  * documentation and/or other materials provided with the distribution;
  12  * neither the name of the copyright holders nor the names of its
  13  * contributors may be used to endorse or promote products derived from
  14  * this software without specific prior written permission.
  15  *
  16  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  17  * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  18  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  19  * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  20  * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  21  * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  22  * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  23  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  24  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  25  * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  26  * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  27  *
  28  * Authors: Kevin Lim
  29  */
  30
  31 #include "cpu/o3/ras.hh"
  32
  33 void
  34 ReturnAddrStack::init(unsigned _numEntries)
  35 {
  36      numEntries  = _numEntries;
  37      usedEntries = 0;
  38      tos = 0;
  39
  40      addrStack.resize(numEntries);
  41
  42      for (int i = 0; i < numEntries; ++i)
  43          addrStack[i] = 0;
  44 }
  45
  46 void
  47 ReturnAddrStack::reset()
  48 {
  49     usedEntries = 0;
  50     tos = 0;
  51     for (int i = 0; i < numEntries; ++i)
  52         addrStack[i] = 0;
  53 }
  54
  55 void
  56 ReturnAddrStack::push(const Addr &return_addr)
  57 {
  58     incrTos();
  59
  60     addrStack[tos] = return_addr;
  61
  62     if (usedEntries != numEntries) {
  63         ++usedEntries;
  64     }
  65 }
  66
  67 void
  68 ReturnAddrStack::pop()
  69 {
  70     if (usedEntries > 0) {
  71         --usedEntries;
  72     }
  73
  74     decrTos();
  75 }
  76
  77 void
  78 ReturnAddrStack::restore(unsigned top_entry_idx,
  79                          const Addr &restored_target)
  80 {
  81     tos = top_entry_idx;
  82
  83     addrStack[tos] = restored_target;
  84 }