Merge from transactional-memory branch.

From-SVN: r181154

1 files changed, 108 insertions, 0 deletions

diff --git a/libitm/eh_cpp.cc b/libitm/eh_cpp.cc
new file mode 100644
index 00000000000..7cba97cc48c
--- /dev/null
+++ b/libitm/eh_cpp.cc
@@ -0,0 +1,108 @@
+/* Copyright (C) 2009, 2011 Free Software Foundation, Inc.
+   Contributed by Richard Henderson <rth@redhat.com>.
+
+   This file is part of the GNU Transactional Memory Library (libitm).
+
+   Libitm is free software; you can redistribute it and/or modify it
+   under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   Libitm is distributed in the hope that it will be useful, but WITHOUT ANY
+   WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
+   FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+   more details.
+
+   Under Section 7 of GPL version 3, you are granted additional
+   permissions described in the GCC Runtime Library Exception, version
+   3.1, as published by the Free Software Foundation.
+
+   You should have received a copy of the GNU General Public License and
+   a copy of the GCC Runtime Library Exception along with this program;
+   see the files COPYING3 and COPYING.RUNTIME respectively.  If not, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include "libitm_i.h"
+
+using namespace GTM;
+
+/* Everything from libstdc++ is weak, to avoid requiring that library
+   to be linked into plain C applications using libitm.so.  */
+
+#define WEAK  __attribute__((weak))
+
+extern "C" {
+
+extern void *__cxa_allocate_exception (size_t) WEAK;
+extern void __cxa_throw (void *, void *, void *) WEAK;
+extern void *__cxa_begin_catch (void *) WEAK;
+extern void *__cxa_end_catch (void) WEAK;
+extern void __cxa_tm_cleanup (void *, void *, unsigned int) WEAK;
+
+}
+
+
+void *
+_ITM_cxa_allocate_exception (size_t size)
+{
+  void *r = __cxa_allocate_exception (size);
+  gtm_thr()->cxa_unthrown = r;
+  return r;
+}
+
+void
+_ITM_cxa_throw (void *obj, void *tinfo, void *dest)
+{
+  gtm_thr()->cxa_unthrown = NULL;
+  __cxa_throw (obj, tinfo, dest);
+}
+
+void *
+_ITM_cxa_begin_catch (void *exc_ptr)
+{
+  gtm_thr()->cxa_catch_count++;
+  return __cxa_begin_catch (exc_ptr);
+}
+
+void
+_ITM_cxa_end_catch (void)
+{
+  gtm_thr()->cxa_catch_count--;
+  __cxa_end_catch ();
+}
+
+void
+GTM::gtm_thread::revert_cpp_exceptions (gtm_transaction_cp *cp)
+{
+  if (cp)
+    {
+      // If rolling back a nested transaction, only clean up unthrown
+      // exceptions since the last checkpoint. Always reset eh_in_flight
+      // because it just contains the argument provided to
+      // _ITM_commitTransactionEH
+      void *unthrown =
+	  (cxa_unthrown != cp->cxa_unthrown ? cxa_unthrown : NULL);
+      assert (cxa_catch_count >= cp->cxa_catch_count);
+      uint32_t catch_count = cxa_catch_count - cp->cxa_catch_count;
+      if (unthrown || catch_count)
+	{
+	  __cxa_tm_cleanup (unthrown, this->eh_in_flight, catch_count);
+	  cxa_catch_count = cp->cxa_catch_count;
+	  cxa_unthrown = cp->cxa_unthrown;
+	  this->eh_in_flight = NULL;
+	}
+    }
+  else
+    {
+      // Both cxa_catch_count and cxa_unthrown are maximal because EH regions
+      // and transactions are properly nested.
+      if (this->cxa_unthrown || this->cxa_catch_count)
+	{
+	  __cxa_tm_cleanup (this->cxa_unthrown, this->eh_in_flight,
+	      this->cxa_catch_count);
+	  this->cxa_catch_count = 0;
+	  this->cxa_unthrown = NULL;
+	  this->eh_in_flight = NULL;
+	}
+    }
+}