systemc: Fix a "problem" with kill/reset exceptions.

Despite what it says in the spec, the proc_ctrl compliance test throws
a copy of the reset exception it catches, not the original. Because of
that, the code in the kernel which catches the exception gets the base
class, not the derived class with overridden virtual methods, etc.
This happens to work for the Accellera implementation because they
manipulate members of the base class itself which are preserved despite
this bug. To make the test work, we imitate their implementation, even
though it exposes more implementation details through the header files.

Change-Id: I7ed9818c0552869ec790cb7f7bfbe365ade5e49c
Reviewed-on: https://gem5-review.googlesource.com/12045
Reviewed-by: Gabe Black <gabeblack@google.com>
Maintainer: Gabe Black <gabeblack@google.com>

src/systemc/core/sc_process_handle.cc

@@ -39,17 +39,19 @@ namespace sc_core
 const char *
 sc_unwind_exception::what() const throw()
 {
-    panic("%s for base class called.\n", __PRETTY_FUNCTION__);
+    return _isReset ? "RESET" : "KILL";
 }
 
 bool
 sc_unwind_exception::is_reset() const
 {
-    panic("%s for base class called.\n", __PRETTY_FUNCTION__);
+    return _isReset;
 }
 
-sc_unwind_exception::sc_unwind_exception() {}
-sc_unwind_exception::sc_unwind_exception(const sc_unwind_exception &) {}
+sc_unwind_exception::sc_unwind_exception() : _isReset(false) {}
+sc_unwind_exception::sc_unwind_exception(const sc_unwind_exception &e) :
+    _isReset(e._isReset)
+{}
 sc_unwind_exception::~sc_unwind_exception() throw() {}
 
 

src/systemc/ext/core/sc_process_handle.hh

@@ -108,6 +108,7 @@ class sc_unwind_exception : public std::exception
     virtual ~sc_unwind_exception() throw();
 
   protected:
+    bool _isReset;
     sc_unwind_exception();
 };