arm64: LLVMLinux: Add current_stack_pointer() for arm64
authorBehan Webster <behanw@converseincode.com>
Wed, 27 Aug 2014 04:29:29 +0000 (05:29 +0100)
committerWill Deacon <will.deacon@arm.com>
Mon, 8 Sep 2014 13:39:19 +0000 (14:39 +0100)
Define a global named register for current_stack_pointer. The use of this new
variable guarantees that both gcc and clang can access this register in C code.

Signed-off-by: Behan Webster <behanw@converseincode.com>
Reviewed-by: Jan-Simon Möller <dl9pf@gmx.de>
Reviewed-by: Mark Charlebois <charlebm@gmail.com>
Reviewed-by: Olof Johansson <olof@lixom.net>
Acked-by: Will Deacon <will.deacon@arm.com>
Signed-off-by: Will Deacon <will.deacon@arm.com>
arch/arm64/include/asm/thread_info.h

index 45108d802f5e6a1a586ce519edd0375ccad65cd9..356e03774df4b8a160ac55479a555f2644fb438e 100644 (file)
@@ -68,6 +68,11 @@ struct thread_info {
 #define init_thread_info       (init_thread_union.thread_info)
 #define init_stack             (init_thread_union.stack)
 
+/*
+ * how to get the current stack pointer from C
+ */
+register unsigned long current_stack_pointer asm ("sp");
+
 /*
  * how to get the thread information struct from C
  */