Merge zizzer.eecs.umich.edu:/bk/newmem

into  ahchoo.blinky.homelinux.org:/home/gblack/m5/newmem-sparc32

--HG--
extra : convert_revision : bbd0def502e423e64e2c4f6415a4b043b60c7f90

7 files changed, 320 insertions, 348 deletions

diff --git a/src/sim/async.cc b/src/sim/async.cc
new file mode 100644
index 000000000..1a8e499f7
--- /dev/null
+++ b/src/sim/async.cc
@@ -0,0 +1,38 @@
+/*
+ * Copyright (c) 2000-2005 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: Nathan Binkert
+ */
+
+volatile bool async_event = false;
+volatile bool async_statdump = false;
+volatile bool async_statreset = false;
+volatile bool async_exit = false;
+volatile bool async_io = false;
+volatile bool async_alarm = false;
+volatile bool async_exception = false;
+
diff --git a/src/sim/async.hh b/src/sim/async.hh
index 6ee5eb46a..932f975d2 100644
--- a/src/sim/async.hh
+++ b/src/sim/async.hh
@@ -43,7 +43,8 @@
 /// @note See the PollQueue object (in pollevent.hh) for the use of async_io and async_alarm.
 //@{
 extern volatile bool async_event;	///< Some asynchronous event has happened.
-extern volatile bool async_dump;	///< Async request to dump stats.
+extern volatile bool async_statdump;	///< Async request to dump stats.
+extern volatile bool async_statreset;	///< Async request to reset stats.
 extern volatile bool async_exit;	///< Async request to exit simulator.
 extern volatile bool async_io;		///< Async I/O request (SIGIO).
 extern volatile bool async_alarm;	///< Async alarm event (SIGALRM).
diff --git a/src/sim/core.cc b/src/sim/core.cc
new file mode 100644
index 000000000..24cc33da2
--- /dev/null
+++ b/src/sim/core.cc
@@ -0,0 +1,76 @@
+/*
+ * Copyright (c) 2006 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: Nathan Binkert
+ *          Steve Reinhardt
+ */
+
+#include <iostream>
+#include <string>
+
+#include "base/callback.hh"
+#include "base/output.hh"
+
+using namespace std;
+
+void
+setOutputDir(const string &dir)
+{
+    simout.setDirectory(dir);
+}
+
+/**
+ * Queue of C++ callbacks to invoke on simulator exit.
+ */
+inline CallbackQueue &
+exitCallbacks()
+{
+    static CallbackQueue theQueue;
+    return theQueue;
+}
+
+/**
+ * Register an exit callback.
+ */
+void
+registerExitCallback(Callback *callback)
+{
+    exitCallbacks().add(callback);
+}
+
+/**
+ * Do C++ simulator exit processing.  Exported to SWIG to be invoked
+ * when simulator terminates via Python's atexit mechanism.
+ */
+void
+doExitCleanup()
+{
+    exitCallbacks().process();
+    exitCallbacks().clear();
+
+    cout.flush();
+}
diff --git a/src/sim/core.hh b/src/sim/core.hh
new file mode 100644
index 000000000..2ef21c4b6
--- /dev/null
+++ b/src/sim/core.hh
@@ -0,0 +1,40 @@
+/*
+ * Copyright (c) 2006 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: Nathan Binkert
+ *          Steve Reinhardt
+ */
+
+#include <Python.h>
+#include <string>
+
+#include "base/callback.hh"
+
+void setOutputDir(const std::string &dir);
+
+void registerExitCallback(Callback *callback);
+void doExitCleanup();
diff --git a/src/sim/main.cc b/src/sim/main.cc
index 8e47ac6a0..e7fb4039e 100644
--- a/src/sim/main.cc
+++ b/src/sim/main.cc
@@ -25,79 +25,38 @@
  * (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 Raasch
- *          Nathan Binkert
- *          Steve Reinhardt
+ * Authors: Nathan Binkert
  */
 
-///
-/// @file sim/main.cc
-///
-#include <Python.h>	// must be before system headers... see Python docs
+#include <Python.h>
 
-#include <sys/types.h>
-#include <sys/stat.h>
-#include <errno.h>
-#include <libgen.h>
-#include <stdlib.h>
-#include <signal.h>
-#include <getopt.h>
-
-#include <list>
+#include <iostream>
 #include <string>
-#include <vector>
 
-#include "base/callback.hh"
-#include "base/inifile.hh"
+#include "base/cprintf.hh"
 #include "base/misc.hh"
-#include "base/output.hh"
-#include "base/pollevent.hh"
-#include "base/statistics.hh"
-#include "base/stats/output.hh"
-#include "base/str.hh"
-#include "base/time.hh"
 #include "config/pythonhome.hh"
-#include "cpu/base.hh"
-#include "cpu/smt.hh"
-#include "mem/mem_object.hh"
-#include "mem/port.hh"
 #include "python/swig/init.hh"
 #include "sim/async.hh"
-#include "sim/builder.hh"
 #include "sim/host.hh"
-#include "sim/serialize.hh"
-#include "sim/sim_events.hh"
-#include "sim/sim_exit.hh"
-#include "sim/sim_object.hh"
-#include "sim/system.hh"
-#include "sim/stat_control.hh"
-#include "sim/stats.hh"
 #include "sim/root.hh"
 
 using namespace std;
 
-// See async.h.
-volatile bool async_event = false;
-volatile bool async_dump = false;
-volatile bool async_dumpreset = false;
-volatile bool async_exit = false;
-volatile bool async_io = false;
-volatile bool async_alarm = false;
-volatile bool async_exception = false;
-
 /// Stats signal handler.
 void
 dumpStatsHandler(int sigtype)
 {
     async_event = true;
-    async_dump = true;
+    async_statdump = true;
 }
 
 void
 dumprstStatsHandler(int sigtype)
 {
     async_event = true;
-    async_dumpreset = true;
+    async_statdump = true;
+    async_statreset = true;
 }
 
 /// Exit signal handler.
@@ -112,7 +71,7 @@ exitNowHandler(int sigtype)
 void
 abortHandler(int sigtype)
 {
-    cerr << "Program aborted at cycle " << curTick << endl;
+    ccprintf(cerr, "Program aborted at cycle %d\n", curTick);
 }
 
 int
@@ -160,301 +119,3 @@ main(int argc, char **argv)
     // clean up Python intepreter.
     Py_Finalize();
 }
-
-
-void
-setOutputDir(const string &dir)
-{
-    simout.setDirectory(dir);
-}
-
-
-IniFile inifile;
-
-SimObject *
-createSimObject(const string &name)
-{
-    return SimObjectClass::createObject(inifile, name);
-}
-
-
-/**
- * Pointer to the Python function that maps names to SimObjects.
- */
-PyObject *resolveFunc = NULL;
-
-/**
- * Convert a pointer to the Python object that SWIG wraps around a C++
- * SimObject pointer back to the actual C++ pointer.  See main.i.
- */
-extern "C" SimObject *convertSwigSimObjectPtr(PyObject *);
-
-
-SimObject *
-resolveSimObject(const string &name)
-{
-    PyObject *pyPtr = PyEval_CallFunction(resolveFunc, "(s)", name.c_str());
-    if (pyPtr == NULL) {
-        PyErr_Print();
-        panic("resolveSimObject: failure on call to Python for %s", name);
-    }
-
-    SimObject *simObj = convertSwigSimObjectPtr(pyPtr);
-    if (simObj == NULL)
-        panic("resolveSimObject: failure on pointer conversion for %s", name);
-
-    return simObj;
-}
-
-
-/**
- * Load config.ini into C++ database.  Exported to Python via SWIG;
- * invoked from m5.instantiate().
- */
-void
-loadIniFile(PyObject *_resolveFunc)
-{
-    resolveFunc = _resolveFunc;
-    configStream = simout.find("config.out");
-
-    // The configuration database is now complete; start processing it.
-    inifile.load(simout.resolve("config.ini"));
-
-    // Initialize statistics database
-    Stats::initSimStats();
-}
-
-
-/**
- * Look up a MemObject port.  Helper function for connectPorts().
- */
-Port *
-lookupPort(SimObject *so, const std::string &name, int i)
-{
-    MemObject *mo = dynamic_cast<MemObject *>(so);
-    if (mo == NULL) {
-        warn("error casting SimObject %s to MemObject", so->name());
-        return NULL;
-    }
-
-    Port *p = mo->getPort(name, i);
-    if (p == NULL)
-        warn("error looking up port %s on object %s", name, so->name());
-    return p;
-}
-
-
-/**
- * Connect the described MemObject ports.  Called from Python via SWIG.
- */
-int
-connectPorts(SimObject *o1, const std::string &name1, int i1,
-             SimObject *o2, const std::string &name2, int i2)
-{
-    Port *p1 = lookupPort(o1, name1, i1);
-    Port *p2 = lookupPort(o2, name2, i2);
-
-    if (p1 == NULL || p2 == NULL) {
-        warn("connectPorts: port lookup error");
-        return 0;
-    }
-
-    p1->setPeer(p2);
-    p2->setPeer(p1);
-
-    return 1;
-}
-
-/**
- * Do final initialization steps after object construction but before
- * start of simulation.
- */
-void
-finalInit()
-{
-    // Do a second pass to finish initializing the sim objects
-    SimObject::initAll();
-
-    // Restore checkpointed state, if any.
-#if 0
-    configHierarchy.unserializeSimObjects();
-#endif
-
-    SimObject::regAllStats();
-
-    // Check to make sure that the stats package is properly initialized
-    Stats::check();
-
-    // Reset to put the stats in a consistent state.
-    Stats::reset();
-
-    SimStartup();
-}
-
-/** Simulate for num_cycles additional cycles.  If num_cycles is -1
- * (the default), do not limit simulation; some other event must
- * terminate the loop.  Exported to Python via SWIG.
- * @return The SimLoopExitEvent that caused the loop to exit.
- */
-SimLoopExitEvent *
-simulate(Tick num_cycles = MaxTick)
-{
-    warn("Entering event queue @ %d.  Starting simulation...\n", curTick);
-
-    if (num_cycles < 0)
-        fatal("simulate: num_cycles must be >= 0 (was %d)\n", num_cycles);
-    else if (curTick + num_cycles < 0)  //Overflow
-        num_cycles = MaxTick;
-    else
-        num_cycles = curTick + num_cycles;
-
-    Event *limit_event = schedExitSimLoop("simulate() limit reached",
-                                          num_cycles);
-
-    while (1) {
-        // there should always be at least one event (the SimLoopExitEvent
-        // we just scheduled) in the queue
-        assert(!mainEventQueue.empty());
-        assert(curTick <= mainEventQueue.nextTick() &&
-               "event scheduled in the past");
-
-        // forward current cycle to the time of the first event on the
-        // queue
-        curTick = mainEventQueue.nextTick();
-        Event *exit_event = mainEventQueue.serviceOne();
-        if (exit_event != NULL) {
-            // hit some kind of exit event; return to Python
-            // event must be subclass of SimLoopExitEvent...
-            SimLoopExitEvent *se_event = dynamic_cast<SimLoopExitEvent *>(exit_event);
-            if (se_event == NULL)
-                panic("Bogus exit event class!");
-
-            // if we didn't hit limit_event, delete it
-            if (se_event != limit_event) {
-                assert(limit_event->scheduled());
-                limit_event->deschedule();
-                delete limit_event;
-            }
-
-            return se_event;
-        }
-
-        if (async_event) {
-            async_event = false;
-            if (async_dump) {
-                async_dump = false;
-                Stats::StatEvent(true, false);
-            }
-
-            if (async_dumpreset) {
-                async_dumpreset = false;
-                Stats::StatEvent(true, true);
-            }
-
-            if (async_exit) {
-                async_exit = false;
-                exitSimLoop("user interrupt received");
-            }
-
-            if (async_io || async_alarm) {
-                async_io = false;
-                async_alarm = false;
-                pollQueue.service();
-            }
-
-            if (async_exception) {
-                async_exception = false;
-                return NULL;
-            }
-        }
-    }
-
-    // not reached... only exit is return on SimLoopExitEvent
-}
-
-Event *
-createCountedDrain()
-{
-    return new CountedDrainEvent();
-}
-
-void
-cleanupCountedDrain(Event *counted_drain)
-{
-    CountedDrainEvent *event =
-        dynamic_cast<CountedDrainEvent *>(counted_drain);
-    if (event == NULL) {
-        fatal("Called cleanupCountedDrain() on an event that was not "
-              "a CountedDrainEvent.");
-    }
-    assert(event->getCount() == 0);
-    delete event;
-}
-
-void
-serializeAll(const std::string &cpt_dir)
-{
-    Serializable::serializeAll(cpt_dir);
-}
-
-void
-unserializeAll(const std::string &cpt_dir)
-{
-    Serializable::unserializeAll(cpt_dir);
-}
-
-/**
- * Queue of C++ callbacks to invoke on simulator exit.
- */
-CallbackQueue&
-exitCallbacks()
-{
-    static CallbackQueue theQueue;
-    return theQueue;
-}
-
-/**
- * Register an exit callback.
- */
-void
-registerExitCallback(Callback *callback)
-{
-    exitCallbacks().add(callback);
-}
-
-BaseCPU *
-convertToBaseCPUPtr(SimObject *obj)
-{
-    BaseCPU *ptr = dynamic_cast<BaseCPU *>(obj);
-
-    if (ptr == NULL)
-        warn("Casting to BaseCPU pointer failed");
-    return ptr;
-}
-
-System *
-convertToSystemPtr(SimObject *obj)
-{
-    System *ptr = dynamic_cast<System *>(obj);
-
-    if (ptr == NULL)
-        warn("Casting to System pointer failed");
-    return ptr;
-}
-
-
-/**
- * Do C++ simulator exit processing.  Exported to SWIG to be invoked
- * when simulator terminates via Python's atexit mechanism.
- */
-void
-doExitCleanup()
-{
-    exitCallbacks().process();
-    exitCallbacks().clear();
-
-    cout.flush();
-
-    // print simulation stats
-    Stats::dump();
-}
diff --git a/src/sim/simulate.cc b/src/sim/simulate.cc
new file mode 100644
index 000000000..55cbb50a9
--- /dev/null
+++ b/src/sim/simulate.cc
@@ -0,0 +1,121 @@
+/*
+ * Copyright (c) 2006 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: Nathan Binkert
+ *          Steve Reinhardt
+ */
+
+#include "base/misc.hh"
+#include "base/pollevent.hh"
+#include "sim/stat_control.hh"
+#include "sim/async.hh"
+#include "sim/eventq.hh"
+#include "sim/host.hh"
+#include "sim/sim_events.hh"
+#include "sim/sim_exit.hh"
+#include "sim/simulate.hh"
+
+/** Simulate for num_cycles additional cycles.  If num_cycles is -1
+ * (the default), do not limit simulation; some other event must
+ * terminate the loop.  Exported to Python via SWIG.
+ * @return The SimLoopExitEvent that caused the loop to exit.
+ */
+SimLoopExitEvent *
+simulate(Tick num_cycles)
+{
+    warn("Entering event queue @ %d.  Starting simulation...\n", curTick);
+
+    if (num_cycles < 0)
+        fatal("simulate: num_cycles must be >= 0 (was %d)\n", num_cycles);
+    else if (curTick + num_cycles < 0)  //Overflow
+        num_cycles = MaxTick;
+    else
+        num_cycles = curTick + num_cycles;
+
+    Event *limit_event;
+    limit_event = schedExitSimLoop("simulate() limit reached", num_cycles);
+
+    while (1) {
+        // there should always be at least one event (the SimLoopExitEvent
+        // we just scheduled) in the queue
+        assert(!mainEventQueue.empty());
+        assert(curTick <= mainEventQueue.nextTick() &&
+               "event scheduled in the past");
+
+        // forward current cycle to the time of the first event on the
+        // queue
+        curTick = mainEventQueue.nextTick();
+        Event *exit_event = mainEventQueue.serviceOne();
+        if (exit_event != NULL) {
+            // hit some kind of exit event; return to Python
+            // event must be subclass of SimLoopExitEvent...
+            SimLoopExitEvent *se_event;
+            se_event = dynamic_cast<SimLoopExitEvent *>(exit_event);
+
+            if (se_event == NULL)
+                panic("Bogus exit event class!");
+
+            // if we didn't hit limit_event, delete it
+            if (se_event != limit_event) {
+                assert(limit_event->scheduled());
+                limit_event->deschedule();
+                delete limit_event;
+            }
+
+            return se_event;
+        }
+
+        if (async_event) {
+            async_event = false;
+            if (async_statdump || async_statreset) {
+                async_statdump = false;
+                async_statreset = false;
+
+                Stats::StatEvent(async_statdump, async_statreset);
+            }
+
+            if (async_exit) {
+                async_exit = false;
+                exitSimLoop("user interrupt received");
+            }
+
+            if (async_io || async_alarm) {
+                async_io = false;
+                async_alarm = false;
+                pollQueue.service();
+            }
+
+            if (async_exception) {
+                async_exception = false;
+                return NULL;
+            }
+        }
+    }
+
+    // not reached... only exit is return on SimLoopExitEvent
+}
+
diff --git a/src/sim/simulate.hh b/src/sim/simulate.hh
new file mode 100644
index 000000000..139bddb82
--- /dev/null
+++ b/src/sim/simulate.hh
@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) 2006 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: Nathan Binkert
+ *          Steve Reinhardt
+ */
+
+#include "sim/host.hh"
+#include "sim/sim_events.hh"
+
+SimLoopExitEvent *simulate(Tick num_cycles = MaxTick);