systemc: Ignore immediate self notifications.

Change-Id: If5140bd86159e9257eb9e6ccb8301dd6349dacff
Reviewed-on: https://gem5-review.googlesource.com/c/13310
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

src/systemc/core/sensitivity.cc

@@ -55,14 +55,31 @@ Sensitivity::satisfy()
 }
 
 bool
-Sensitivity::notify(Event *e)
+Sensitivity::notifyWork(Event *e)
 {
-    if (process->disabled())
-        return false;
     satisfy();
     return true;
 }
 
+bool
+Sensitivity::notify(Event *e)
+{
+    if (scheduler.current() == process) {
+        static bool warned = false;
+        if (!warned) {
+            SC_REPORT_WARNING("(W536) immediate self-notification ignored "
+                    "as of IEEE 1666-2011", process->name());
+            warned = true;
+        }
+        return false;
+    }
+
+    if (process->disabled())
+        return false;
+
+    return notifyWork(e);
+}
+
 bool
 Sensitivity::ofMethod()
 {
@@ -203,11 +220,8 @@ DynamicSensitivityEventOrList::DynamicSensitivityEventOrList(
 {}
 
 bool
-DynamicSensitivityEventOrList::notify(Event *e)
+DynamicSensitivityEventOrList::notifyWork(Event *e)
 {
-    if (process->disabled())
-        return false;
-
     events.erase(e->sc_event());
 
     // All the other events need this deleted from their lists since this
@@ -225,11 +239,8 @@ DynamicSensitivityEventAndList::DynamicSensitivityEventAndList(
 {}
 
 bool
-DynamicSensitivityEventAndList::notify(Event *e)
+DynamicSensitivityEventAndList::notifyWork(Event *e)
 {
-    if (process->disabled())
-        return false;
-
     events.erase(e->sc_event());
 
     // This sensitivity is satisfied if all events have triggered.

src/systemc/core/sensitivity.hh

@@ -76,7 +76,8 @@ class Sensitivity
     virtual void clear() = 0;
 
     void satisfy();
-    virtual bool notify(Event *e);
+    virtual bool notifyWork(Event *e);
+    bool notify(Event *e);
 
     enum Category
     {
@@ -276,7 +277,7 @@ class DynamicSensitivityEventOrList :
     DynamicSensitivityEventOrList(
             Process *p, const sc_core::sc_event_or_list *eol);
 
-    bool notify(Event *e) override;
+    bool notifyWork(Event *e) override;
 };
 
 //XXX This sensitivity can't be reused. To reset it, it has to be deleted and
@@ -292,7 +293,7 @@ class DynamicSensitivityEventAndList :
     DynamicSensitivityEventAndList(
             Process *p, const sc_core::sc_event_and_list *eal);
 
-    bool notify(Event *e) override;
+    bool notifyWork(Event *e) override;
 };
 
 } // namespace sc_gem5