From mboxrd@z Thu Jan 1 00:00:00 1970 From: behanw@converseincode.com (behanw at converseincode.com) Date: Fri, 6 Sep 2013 17:28:07 -0400 Subject: [PATCH 1/5] arm: LLVMLinux: Add current_stack_pointer macro for ARM In-Reply-To: <1378502899-1241-1-git-send-email-behanw@converseincode.com> References: <1378502899-1241-1-git-send-email-behanw@converseincode.com> Message-ID: <1378502899-1241-2-git-send-email-behanw@converseincode.com> To: linux-arm-kernel@lists.infradead.org List-Id: linux-arm-kernel.lists.infradead.org From: Behan Webster A macro to get the current stack pointer which allows for a single place in which to do so with ASM. Before this named registers (a gcc extension) was used to get the stack pointer. Using ASM is a more portable way of getting the stack pointer which works with both gcc and clang. This macro is of the same name used in the X86 arch. Author: Behan Webster Signed-off-by: Behan Webster Reviewed-by: Jan-Simon M?ller --- arch/arm/include/asm/thread_info.h | 9 +++++++++ 1 file changed, 9 insertions(+) diff --git a/arch/arm/include/asm/thread_info.h b/arch/arm/include/asm/thread_info.h index df5e13d..94283f8 100644 --- a/arch/arm/include/asm/thread_info.h +++ b/arch/arm/include/asm/thread_info.h @@ -100,6 +100,15 @@ struct thread_info { #define init_stack (init_thread_union.stack) /* + * how to get the current stack pointer from C + */ +#define current_stack_pointer ({ \ + unsigned long current_sp; \ + asm ("mov %0, r13" : "=r" (current_sp)); \ + current_sp; \ +}) + +/* * how to get the thread information struct from C */ static inline struct thread_info *current_thread_info(void) __attribute_const__; -- 1.8.1.2