thread_state.hh

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#ifndef __CPU_O3_THREAD_STATE_HH__
#define __CPU_O3_THREAD_STATE_HH__
 
#include "base/callback.hh"
#include "base/compiler.hh"
#include "base/output.hh"
#include "cpu/thread_context.hh"
#include "cpu/thread_state.hh"
#include "sim/full_system.hh"
#include "sim/sim_exit.hh"
 
class Event;
class FunctionalMemory;
class Process;
 
template <class Impl>
struct O3ThreadState : public ThreadState {
    typedef ThreadContext::Status Status;
    typedef typename Impl::O3CPU O3CPU;
 
  private:
    O3CPU *cpu;
 
  public:
    PCEventQueue pcEventQueue;
    EventQueue comInstEventQueue;
 
    /* This variable controls if writes to a thread context should cause a all
     * dynamic/speculative state to be thrown away. Nominally this is the
     * desired behavior because the external thread context write has updated
     * some state that could be used by an inflight instruction, however there
     * are some cases like in a fault/trap handler where this behavior would
     * lead to successive restarts and forward progress couldn't be made. This
     * variable controls if the squashing will occur.
     */
    bool noSquashFromTC;
 
    bool trapPending;
 
    std::unique_ptr<BaseHTMCheckpoint> htmCheckpoint;
 
    O3ThreadState(O3CPU *_cpu, int _thread_num, Process *_process)
        : ThreadState(_cpu, _thread_num, _process), cpu(_cpu),
          comInstEventQueue("instruction-based event queue"),
          noSquashFromTC(false), trapPending(false), tc(nullptr)
    {
    }
 
    void serialize(CheckpointOut &cp) const override
    {
        ThreadState::serialize(cp);
        // Use the ThreadContext serialization helper to serialize the
        // TC.
        ::serialize(*tc, cp);
    }
 
    void unserialize(CheckpointIn &cp) override
    {
        // Prevent squashing - we don't have any instructions in
        // flight that we need to squash since we just instantiated a
        // clean system.
        noSquashFromTC = true;
        ThreadState::unserialize(cp);
        // Use the ThreadContext serialization helper to unserialize
        // the TC.
        ::unserialize(*tc, cp);
        noSquashFromTC = false;
    }
 
    ThreadContext *tc;
 
    ThreadContext *getTC() { return tc; }
 
    void syscall() { process->syscall(tc); }
};
 
#endif // __CPU_O3_THREAD_STATE_HH__