sparc64 attempt

src/libthread/Linux-sparc64-swapcontext.c

@@ -0,0 +1,48 @@
+/* Copyright (C) 2001 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Jakub Jelinek <jakub@redhat.com>.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <ucontext.h>
+
+extern int __getcontext (ucontext_t *ucp);
+extern int __setcontext (const ucontext_t *ucp, int restoremask);
+
+int
+__swapcontext (ucontext_t *oucp, const ucontext_t *ucp)
+{
+  extern void __swapcontext_ret (void);
+  /* Save the current machine context to oucp.  */
+  __getcontext (oucp);
+  /* Modify oucp to skip the __setcontext call on reactivation.  */
+  oucp->uc_mcontext.mc_gregs[MC_PC] = (long) __swapcontext_ret;
+  oucp->uc_mcontext.mc_gregs[MC_NPC] = ((long) __swapcontext_ret) + 4;
+  /* Restore the machine context in ucp.  */
+  __setcontext (ucp, 1);
+  return 0;
+}
+
+asm ("							\n\
+	.text						\n\
+	.type	__swapcontext_ret, #function		\n\
+__swapcontext_ret:					\n\
+	return	%i7 + 8					\n\
+	 clr	%o0					\n\
+	.size	__swapcontext_ret, .-__swapcontext_ret	\n\
+     ");
+
+weak_alias (__swapcontext, swapcontext)