aarch64: move to C trampoline

arch/aarch64/defs.h

@@ -18,6 +18,9 @@
 # define ESR_MAGIC	0x45535201
 #endif
 
+#define FETCH_LINKPTR(dest) \
+	asm("mov	x0, %0" : "=rm" ((dest)))
+
 #include "common-defs.h"
 
 #endif

arch/aarch64/startcontext.S

@@ -1,22 +0,0 @@
-/*
- * Copyright (c) 2018 Ariadne Conill <ariadne@dereferenced.org>
- *
- * Permission to use, copy, modify, and/or distribute this software for any
- * purpose with or without fee is hereby granted, provided that the above
- * copyright notice and this permission notice appear in all copies.
- *
- * This software is provided 'as is' and without any warranty, express or
- * implied.  In no event shall the authors be liable for any damages arising
- * from the use of this software.
- */
-
-#include "defs.h"
-
-FUNC(libucontext_trampoline)
-	/* get the proper context into position and test for NULL */
-	mov	x0, x19
-	cbnz	x0, libucontext_setcontext
-
-	/* something went wrong, exit */
-	b	exit
-END(libucontext_trampoline)

arch/aarch64/trampoline.c

@@ -0,0 +1,2 @@
+#include "defs.h"
+#include "common-trampoline.c"