systemc: Implement much of events, event lists and event exprs.

Three things aren't yet implemented, waking up processes which are
sensitive to the event, triggering of events, and garbage collecting
list objects which came from expression objects.

The garbage collection aspect is problematic since there doesn't seem
to be a correct way to implement it given the constraints in the spec,
including the way that's implemented by Accellera. It's something that
will need to be dealt with at some point, but in the interest of
forward progress it's being ignored for now.

Change-Id: Ic4e3c219ff482729f1f1302ab10181a798d48041
Reviewed-on: https://gem5-review.googlesource.com/11711
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

1 files changed, 145 insertions, 0 deletions

diff --git a/src/systemc/core/event.cc b/src/systemc/core/event.cc
new file mode 100644
index 000000000..63fcabe4f
--- /dev/null
+++ b/src/systemc/core/event.cc
@@ -0,0 +1,145 @@
+/*
+ * Copyright 2018 Google, Inc.
+ *
+ * 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: Gabe Black
+ */
+
+#include "systemc/core/event.hh"
+
+#include <cstring>
+#include <utility>
+
+#include "systemc/core/module.hh"
+#include "systemc/core/scheduler.hh"
+
+namespace sc_gem5
+{
+
+Event::Event(sc_core::sc_event *_sc_event) : Event(_sc_event, "") {}
+
+Event::Event(sc_core::sc_event *_sc_event, const char *_basename) :
+    _sc_event(_sc_event), _basename(_basename)
+{
+    Module *p = currentModule();
+
+    if (p)
+        parent = p->obj()->sc_obj();
+    else if (scheduler.current())
+        parent = scheduler.current();
+
+    if (parent) {
+        Object *obj = Object::getFromScObject(parent);
+        parentIt = obj->addChildEvent(_sc_event);
+    } else {
+        parentIt = topLevelEvents.emplace(topLevelEvents.end(), _sc_event);
+    }
+
+    if (parent)
+        _name = std::string(parent->name()) + "." + _basename;
+    else
+        _name = _basename;
+
+    allEvents.emplace(allEvents.end(), _sc_event);
+
+    // Determine if we're in the hierarchy (created once initialization starts
+    // means no).
+}
+
+Event::~Event()
+{
+    if (parent) {
+        Object *obj = Object::getFromScObject(parent);
+        obj->delChildEvent(parentIt);
+    } else {
+        std::swap(*parentIt, topLevelEvents.back());
+        topLevelEvents.pop_back();
+    }
+
+    EventsIt it = findEvent(_name);
+    std::swap(*it, allEvents.back());
+    allEvents.pop_back();
+}
+
+const std::string &
+Event::name() const
+{
+    return _name;
+}
+
+const std::string &
+Event::basename() const
+{
+    return _basename;
+}
+
+bool
+Event::inHierarchy() const
+{
+    return _name.length() != 0;
+}
+
+sc_core::sc_object *
+Event::getParentObject() const
+{
+    return parent;
+}
+
+void
+Event::notify()
+{
+}
+
+void
+Event::notify(const sc_core::sc_time &t)
+{
+}
+
+void
+Event::cancel()
+{
+}
+
+bool
+Event::triggered() const
+{
+    return false;
+}
+
+Events topLevelEvents;
+Events allEvents;
+
+EventsIt
+findEvent(const std::string &name)
+{
+    EventsIt it;
+    for (it = allEvents.begin(); it != allEvents.end(); it++)
+        if (!strcmp((*it)->name(), name.c_str()))
+            break;
+
+    return it;
+}
+
+} // namespace sc_gem5