text: /*
   * Copyright (c) 2013-2014 ARM Limited
   * 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.
   *
   * Authors: Andrew Bardsley
   */
  
  /*
   * These classes define an expression language over uint64_t with only
   * a few operators.  This can be used to form expressions for the extra
   * delay required in variable execution time instructions.
   *
   * Expressions, in evaluation, will have access to the ThreadContext and
   * a StaticInst.
   */
  
  #ifndef __CPU_TIMING_EXPR_HH__
  #define __CPU_TIMING_EXPR_HH__
  
  #include "cpu/static_inst.hh"
  #include "cpu/thread_context.hh"
  #include "enums/TimingExprOp.hh"
  #include "params/TimingExpr.hh"
  #include "params/TimingExprBin.hh"
  #include "params/TimingExprIf.hh"
  #include "params/TimingExprLet.hh"
  #include "params/TimingExprLiteral.hh"
  #include "params/TimingExprReadIntReg.hh"
  #include "params/TimingExprRef.hh"
  #include "params/TimingExprSrcReg.hh"
  #include "params/TimingExprUn.hh"
  #include "sim/sim_object.hh"
  
  /** These classes are just the C++ counterparts for those in Expr.py and
   *  are, therefore, documented there */
  
  class TimingExprLet;
  
  /** Object to gather the visible context for evaluation */
  class TimingExprEvalContext
  {
    public:
      /** Special visible context */
      StaticInstPtr inst;
      ThreadContext *thread;
  
      /** Context visible as sub expressions.  results will hold the results
       *  of (lazily) evaluating let's expressions.  resultAvailable elements
       *  are true when a result has actually been evaluated */
      TimingExprLet *let;
      std::vector<uint64_t> results;
      std::vector<bool > resultAvailable;
  
      TimingExprEvalContext(StaticInstPtr inst_,
          ThreadContext *thread_, TimingExprLet *let_);
  };
  
  class TimingExpr : public SimObject
  {
    public:
      TimingExpr(const TimingExprParams *params) :
          SimObject(params)
      { }
  
      virtual uint64_t eval(TimingExprEvalContext &context) = 0;
  };
  
  class TimingExprLiteral : public TimingExpr
  {
    public:
      uint64_t value;
  
      TimingExprLiteral(const TimingExprLiteralParams *params) :
          TimingExpr(params),
          value(params->value)
      { }
  
      uint64_t eval(TimingExprEvalContext &context) { return value; }
  };
  
  class TimingExprSrcReg : public TimingExpr
  {
    public:
      unsigned int index;
  
      TimingExprSrcReg(const TimingExprSrcRegParams *params) :
          TimingExpr(params),
          index(params->index)
      { }
  
      uint64_t eval(TimingExprEvalContext &context);
  };
  
  class TimingExprReadIntReg : public TimingExpr
  {
    public:
      TimingExpr *reg;
  
      TimingExprReadIntReg(const TimingExprReadIntRegParams *params) :
          TimingExpr(params),
          reg(params->reg)
      { }
  
      uint64_t eval(TimingExprEvalContext &context);
  };
  
  class TimingExprLet : public TimingExpr
  {
    public:
      std::vector<TimingExpr *> defns;
      TimingExpr *expr;
  
      TimingExprLet(const TimingExprLetParams *params) :
          TimingExpr(params),
          defns(params->defns),
          expr(params->expr)
      { }
  
      uint64_t eval(TimingExprEvalContext &context);
  };
  
  class TimingExprRef : public TimingExpr
  {
    public:
      unsigned int index;
  
      TimingExprRef(const TimingExprRefParams *params) :
          TimingExpr(params),
          index(params->index)
      { }
  
      uint64_t eval(TimingExprEvalContext &context);
  };
  
  class TimingExprUn : public TimingExpr
  {
    public:
      Enums::TimingExprOp op;
      TimingExpr *arg;
  
      TimingExprUn(const TimingExprUnParams *params) :
          TimingExpr(params),
          op(params->op),
          arg(params->arg)
      { }
  
      uint64_t eval(TimingExprEvalContext &context);
  };
  
  class TimingExprBin : public TimingExpr
  {
    public:
      Enums::TimingExprOp op;
      TimingExpr *left;
      TimingExpr *right;
  
      TimingExprBin(const TimingExprBinParams *params) :
          TimingExpr(params),
          op(params->op),
          left(params->left),
          right(params->right)
      { }
  
      uint64_t eval(TimingExprEvalContext &context);
  };
  
  class TimingExprIf : public TimingExpr
  {
    public:
      TimingExpr *cond;
      TimingExpr *trueExpr;
      TimingExpr *falseExpr;
  
      TimingExprIf(const TimingExprIfParams *params) :
          TimingExpr(params),
          cond(params->cond),
          trueExpr(params->trueExpr),
          falseExpr(params->falseExpr)
      { }
  
      uint64_t eval(TimingExprEvalContext &context);
  };
  
  #endif
  