1 files changed, 73 insertions, 0 deletions
diff --git a/sysdeps/unix/sysv/linux/arc/makecontext.c b/sysdeps/unix/sysv/linux/arc/makecontext.c
new file mode 100644
index 0000000000..5ded1ad3e2
--- /dev/null
+++ b/sysdeps/unix/sysv/linux/arc/makecontext.c
@@ -0,0 +1,73 @@
+/* Create new context for ARC.
+   Copyright (C) 2020 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+
+   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, see
+   <https://www.gnu.org/licenses/>.  */
+
+#include <sysdep.h>
+#include <stdarg.h>
+#include <stdint.h>
+#include <sys/ucontext.h>
+
+void
+__makecontext (ucontext_t *ucp, void (*func) (void), int argc, ...)
+{
+  extern void __startcontext (void) attribute_hidden;
+  unsigned long int sp, *r;
+  va_list vl;
+  int i, reg_args, stack_args;
+
+  sp = ((unsigned long int) ucp->uc_stack.ss_sp + ucp->uc_stack.ss_size) & ~7;
+
+  ucp->uc_mcontext.__sp = sp;
+  ucp->uc_mcontext.__fp = 0;
+
+  /* __startcontext is sort of trampoline to invoke @func
+     From setcontext pov, the resume address is __startcontext,
+     set it up in BLINK place holder.  */
+
+  ucp->uc_mcontext.__blink = (unsigned long int) &__startcontext;
+
+  /* __startcontext passed 2 types of args
+       - args to @func setup in canonical r0-r7
+       - @func and next function in r14,r15.   */
+
+  ucp->uc_mcontext.__r14 = (unsigned long int) func;
+  ucp->uc_mcontext.__r15 = (unsigned long int) ucp->uc_link;
+
+  r = &ucp->uc_mcontext.__r0;
+
+  va_start (vl, argc);
+
+  reg_args = argc > 8 ? 8 : argc;
+  for (i = 0; i < reg_args; i++)
+    *r-- = va_arg (vl, unsigned long int);
+
+  stack_args = argc - reg_args;
+
+  if (__glibc_unlikely (stack_args > 0))
+    {
+      sp -= stack_args * sizeof (unsigned long int);
+      ucp->uc_mcontext.__sp = sp;
+      r = (unsigned long int *) sp;
+
+      for (i = 0; i < stack_args; i++)
+        *r++ = va_arg (vl, unsigned long int);
+    }
+
+  va_end (vl);
+}
+
+weak_alias (__makecontext, makecontext)