systemc: Distinguish internal events from normal sc_events.

The internal events aren't supposed to show up in the namespace or as
children of objects.

Change-Id: Id04b9bfe2e1f8f216390dd989797558eaf33d715
Reviewed-on: https://gem5-review.googlesource.com/c/13309
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

9 files changed, 67 insertions, 34 deletions

diff --git a/src/systemc/core/event.cc b/src/systemc/core/event.cc
index 2e356bdb6..de5bc8c32 100644
--- a/src/systemc/core/event.cc
+++ b/src/systemc/core/event.cc
@@ -43,38 +43,47 @@
 namespace sc_gem5
 {
 
-Event::Event(sc_core::sc_event *_sc_event) : Event(_sc_event, nullptr) {}
+Event::Event(sc_core::sc_event *_sc_event, bool internal) :
+    Event(_sc_event, nullptr, internal)
+{}
 
-Event::Event(sc_core::sc_event *_sc_event, const char *_basename_cstr) :
+Event::Event(sc_core::sc_event *_sc_event, const char *_basename_cstr,
+        bool internal) :
     _sc_event(_sc_event), _basename(_basename_cstr ? _basename_cstr : ""),
-    delayedNotify([this]() { this->notify(); }), _triggeredStamp(~0ULL)
+    _inHierarchy(!internal), delayedNotify([this]() { this->notify(); }),
+    _triggeredStamp(~0ULL)
 {
     if (_basename == "" && ::sc_core::sc_is_running())
         _basename = ::sc_core::sc_gen_unique_name("event");
 
-    parent = pickParentObj();
+    parent = internal ? nullptr : pickParentObj();
 
-    std::string original_name = _basename;
-    _basename = pickUniqueName(parent, _basename);
-
-    if (parent) {
-        Object *obj = Object::getFromScObject(parent);
-        obj->addChildEvent(_sc_event);
+    if (internal) {
+        _basename = globalNameGen.gen(_basename);
+        _name = _basename;
     } else {
-        topLevelEvents.emplace(topLevelEvents.end(), _sc_event);
-    }
-
-    std::string path = parent ? (std::string(parent->name()) + ".") : "";
-
-    if (original_name != "" && _basename != original_name) {
-        std::string message = path + original_name +
-            ". Latter declaration will be renamed to " +
-            path + _basename;
-        SC_REPORT_WARNING("(W505) object already exists", message.c_str());
+        std::string original_name = _basename;
+        _basename = pickUniqueName(parent, _basename);
+
+        if (parent) {
+            Object *obj = Object::getFromScObject(parent);
+            obj->addChildEvent(_sc_event);
+        } else {
+            topLevelEvents.emplace(topLevelEvents.end(), _sc_event);
+        }
+
+        std::string path = parent ? (std::string(parent->name()) + ".") : "";
+
+        if (original_name != "" && _basename != original_name) {
+            std::string message = path + original_name +
+                ". Latter declaration will be renamed to " +
+                path + _basename;
+            SC_REPORT_WARNING("(W505) object already exists", message.c_str());
+        }
+
+        _name = path + _basename;
     }
 
-    _name = path + _basename;
-
     allEvents.emplace(allEvents.end(), _sc_event);
 
     // Determine if we're in the hierarchy (created once initialization starts
@@ -86,7 +95,7 @@ Event::~Event()
     if (parent) {
         Object *obj = Object::getFromScObject(parent);
         obj->delChildEvent(_sc_event);
-    } else {
+    } else if (inHierarchy()) {
         EventsIt it = find(topLevelEvents.begin(), topLevelEvents.end(),
                            _sc_event);
         assert(it != topLevelEvents.end());
@@ -117,7 +126,7 @@ Event::basename() const
 bool
 Event::inHierarchy() const
 {
-    return _name.length() != 0;
+    return _inHierarchy;
 }
 
 sc_core::sc_object *
diff --git a/src/systemc/core/event.hh b/src/systemc/core/event.hh
index 75687729f..127e22ae3 100644
--- a/src/systemc/core/event.hh
+++ b/src/systemc/core/event.hh
@@ -60,8 +60,9 @@ class Sensitivity;
 class Event
 {
   public:
-    Event(sc_core::sc_event *_sc_event);
-    Event(sc_core::sc_event *_sc_event, const char *_basename);
+    Event(sc_core::sc_event *_sc_event, bool internal=false);
+    Event(sc_core::sc_event *_sc_event, const char *_basename,
+            bool internal=false);
 
     ~Event();
 
diff --git a/src/systemc/core/module.cc b/src/systemc/core/module.cc
index 8cbde8f70..ec6c7761a 100644
--- a/src/systemc/core/module.cc
+++ b/src/systemc/core/module.cc
@@ -47,6 +47,8 @@ Module *_new_module;
 
 } // anonymous namespace
 
+UniqueNameGen globalNameGen;
+
 Module::Module(const char *name) :
     _name(name), _sc_mod(nullptr), _obj(nullptr), _ended(false),
     _deprecatedConstructor(false), bindingIndex(0)
diff --git a/src/systemc/core/module.hh b/src/systemc/core/module.hh
index 8d6df81e6..b65fdf3bf 100644
--- a/src/systemc/core/module.hh
+++ b/src/systemc/core/module.hh
@@ -68,6 +68,8 @@ class UniqueNameGen
     }
 };
 
+extern UniqueNameGen globalNameGen;
+
 class Module
 {
   private:
diff --git a/src/systemc/core/process.hh b/src/systemc/core/process.hh
index a0657f4be..17961c77f 100644
--- a/src/systemc/core/process.hh
+++ b/src/systemc/core/process.hh
@@ -156,8 +156,8 @@ class Process : public ::sc_core::sc_process_b, public ListNode
         clearDynamic();
     }
 
-    ::sc_core::sc_event _resetEvent;
-    ::sc_core::sc_event _terminatedEvent;
+    InternalScEvent _resetEvent;
+    InternalScEvent _terminatedEvent;
 
     ProcessFuncWrapper *func;
     sc_core::sc_curr_proc_kind _procKind;
diff --git a/src/systemc/core/sc_event.cc b/src/systemc/core/sc_event.cc
index b2dc0e525..0eeae038f 100644
--- a/src/systemc/core/sc_event.cc
+++ b/src/systemc/core/sc_event.cc
@@ -389,6 +389,19 @@ sc_event::operator | (const sc_event_or_list &eol) const
     return expr;
 }
 
+sc_event::sc_event(bool) :
+    _gem5_event(new ::sc_gem5::Event(
+                this, sc_core::sc_gen_unique_name(
+                    "$$$internal kernel event$$$"), true))
+{}
+
+sc_event::sc_event(bool, const char *_name) :
+    _gem5_event(new ::sc_gem5::Event(
+                this,
+                (std::string("$$$internal kernel event$$$") + _name).c_str(),
+                true))
+{}
+
 const std::vector<sc_event *> &
 sc_get_top_level_events()
 {
@@ -404,3 +417,11 @@ sc_find_event(const char *name)
 }
 
 } // namespace sc_core
+
+namespace sc_gem5
+{
+
+InternalScEvent::InternalScEvent() : sc_event(true) {}
+InternalScEvent::InternalScEvent(const char *_name) : sc_event(true, _name) {}
+
+} // namespace sc_gem5
diff --git a/src/systemc/core/sc_interface.cc b/src/systemc/core/sc_interface.cc
index 4b3865e13..93aff6712 100644
--- a/src/systemc/core/sc_interface.cc
+++ b/src/systemc/core/sc_interface.cc
@@ -41,7 +41,7 @@ const sc_event &
 sc_interface::default_event() const
 {
     SC_REPORT_WARNING("(W116) channel doesn't have a default event", "");
-    static sc_event dummy;
+    static sc_gem5::InternalScEvent dummy;
     return dummy;
 }
 
diff --git a/src/systemc/core/sc_module.cc b/src/systemc/core/sc_module.cc
index 0b58f3232..77f0f83f3 100644
--- a/src/systemc/core/sc_module.cc
+++ b/src/systemc/core/sc_module.cc
@@ -97,8 +97,6 @@ newCThreadProcess(const char *name, ProcessFuncWrapper *func)
     return p;
 }
 
-UniqueNameGen nameGen;
-
 } // namespace sc_gem5
 
 namespace sc_core
@@ -836,7 +834,7 @@ sc_gen_unique_name(const char *seed)
     if (p)
         return p->uniqueName(seed);
 
-    return ::sc_gem5::nameGen.gen(seed);
+    return ::sc_gem5::globalNameGen.gen(seed);
 }
 
 bool
diff --git a/src/systemc/core/sc_process_handle.cc b/src/systemc/core/sc_process_handle.cc
index 8bf939801..fff406161 100644
--- a/src/systemc/core/sc_process_handle.cc
+++ b/src/systemc/core/sc_process_handle.cc
@@ -199,7 +199,7 @@ sc_process_handle::terminated_event() const
     if (!_gem5_process) {
         SC_REPORT_WARNING("(W570) attempt to use an empty "
                 "process handle ignored", "terminated_event()");
-        static sc_event non_event;
+        static sc_gem5::InternalScEvent non_event;
         return non_event;
     }
     return _gem5_process->terminatedEvent();
@@ -289,7 +289,7 @@ sc_process_handle::reset_event() const
     if (!_gem5_process) {
         SC_REPORT_WARNING("(W570) attempt to use an empty "
                 "process handle ignored", "reset()");
-        static sc_event non_event;
+        static sc_gem5::InternalScEvent non_event;
         return non_event;
     }
     return _gem5_process->resetEvent();