systemc: Seperate out the sc_main fiber and its bookkeeping.

By pulling out the sc_main fiber (scMainFiber), we can make it
available to different entities in the simulator and avoid having to
have parallel bookkeeping.

Also this will make it possible to hook into sc_main without putting
the code in sc_main.cc.

Change-Id: I7689441424238e9b2e4d2b48e945dea35fd8cc5d
Reviewed-on: https://gem5-review.googlesource.com/c/13977
Reviewed-by: Jason Lowe-Power <jason@lowepower.com>
Maintainer: Gabe Black <gabeblack@google.com>

1 files changed, 22 insertions, 74 deletions

diff --git a/src/systemc/core/sc_main.cc b/src/systemc/core/sc_main.cc
index a5e0366b9..e2f69bb58 100644
--- a/src/systemc/core/sc_main.cc
+++ b/src/systemc/core/sc_main.cc
@@ -38,119 +38,67 @@
 #include "sim/init.hh"
 #include "systemc/core/kernel.hh"
 #include "systemc/core/python.hh"
+#include "systemc/core/sc_main_fiber.hh"
 #include "systemc/core/scheduler.hh"
 #include "systemc/ext/core/messages.hh"
 #include "systemc/ext/core/sc_main.hh"
 #include "systemc/ext/utils/sc_report_handler.hh"
 #include "systemc/utils/report.hh"
 
-// A weak symbol to detect if sc_main has been defined, and if so where it is.
-[[gnu::weak]] int sc_main(int argc, char *argv[]);
-
 namespace sc_core
 {
 
 namespace
 {
 
-bool scMainCalled = false;
-
-int _argc = 0;
-char **_argv = NULL;
-
-class ScMainFiber : public Fiber
-{
-  public:
-    std::string resultStr;
-    int resultInt;
-
-    ScMainFiber() : resultInt(1) {}
-
-    void
-    main()
-    {
-        if (::sc_main) {
-            try {
-                resultInt = ::sc_main(_argc, _argv);
-                if (resultInt)
-                    resultStr = "sc_main returned non-zero";
-                else
-                    resultStr = "sc_main finished";
-                // Make sure no systemc events/notifications are scheduled
-                // after sc_main returns.
-            } catch (const sc_report &r) {
-                // There was an exception nobody caught.
-                resultStr = "uncaught sc_report";
-                sc_gem5::reportHandlerProc(
-                        r, sc_report_handler::get_catch_actions());
-            } catch (...) {
-                // There was some other type of exception we need to wrap.
-                resultStr = "uncaught exception";
-                sc_gem5::reportHandlerProc(
-                        ::sc_gem5::reportifyException(),
-                        sc_report_handler::get_catch_actions());
-            }
-            ::sc_gem5::Kernel::scMainFinished(true);
-            ::sc_gem5::scheduler.clear();
-        } else {
-            // If python tries to call sc_main but no sc_main was defined...
-            fatal("sc_main called but not defined.\n");
-        }
-    }
-};
-
-ScMainFiber scMainFiber;
-
 // This wrapper adapts the python version of sc_main to the c++ version.
 void
 sc_main(pybind11::args args)
 {
-    panic_if(scMainCalled, "sc_main called more than once.");
+    panic_if(::sc_gem5::scMainFiber.called(),
+            "sc_main called more than once.");
 
-    _argc = args.size();
-    _argv = new char *[_argc];
+    int argc = args.size();
+    char **argv = new char *[argc];
 
-    // Initialize all the _argvs to NULL so we can delete [] them
+    // Initialize all the argvs to NULL so we can delete [] them
     // unconditionally.
-    for (int idx = 0; idx < _argc; idx++)
-        _argv[idx] = NULL;
+    for (int idx = 0; idx < argc; idx++)
+        argv[idx] = NULL;
 
     // Attempt to convert all the arguments to strings. If that fails, clean
     // up after ourselves. Also don't count this as a call to sc_main since
     // we never got to the c++ version of that function.
     try {
-        for (int idx = 0; idx < _argc; idx++) {
+        for (int idx = 0; idx < argc; idx++) {
             std::string arg = args[idx].cast<std::string>();
-            _argv[idx] = new char[arg.length() + 1];
-            strcpy(_argv[idx], arg.c_str());
+            argv[idx] = new char[arg.length() + 1];
+            strcpy(argv[idx], arg.c_str());
         }
     } catch (...) {
         // If that didn't work for some reason (probably a conversion error)
-        // blow away _argv and _argc and pass on the exception.
-        for (int idx = 0; idx < _argc; idx++)
-            delete [] _argv[idx];
-        delete [] _argv;
-        _argc = 0;
+        // blow away argv and argc and pass on the exception.
+        for (int idx = 0; idx < argc; idx++)
+            delete [] argv[idx];
+        delete [] argv;
+        argc = 0;
         throw;
     }
 
-    // At this point we're going to call the c++ sc_main, so we can't try
-    // again later.
-    scMainCalled = true;
-
-    scMainFiber.run();
+    ::sc_gem5::scMainFiber.setArgs(argc, argv);
+    ::sc_gem5::scMainFiber.run();
 }
 
 int
 sc_main_result_code()
 {
-    return scMainFiber.resultInt;
+    return ::sc_gem5::scMainFiber.resultInt();
 }
 
 std::string
 sc_main_result_str()
 {
-    return scMainFiber.resultStr;
+    return ::sc_gem5::scMainFiber.resultStr();
 }
 
 // Make our sc_main wrapper available in the internal _m5 python module under
@@ -174,13 +122,13 @@ sc_stop_mode _stop_mode = SC_STOP_FINISH_DELTA;
 int
 sc_argc()
 {
-    return _argc;
+    return ::sc_gem5::scMainFiber.argc();
 }
 
 const char *const *
 sc_argv()
 {
-    return _argv;
+    return ::sc_gem5::scMainFiber.argv();
 }
 
 void