| Message ID | 9a4f9da0615ec658512dd334d931b5acd947ac5d.1551567941.git.stefan@agner.ch (mailing list archive) |
|---|---|
| State | Mainlined, archived |
| Commit | fe09d9c641f2064390afabdf436fe09b35e075ff |
| Headers | show |
| Series | [1/2] ARM: add TUSERCOND() macro for conditional postfix | expand |
diff --git a/arch/arm/include/asm/uaccess.h b/arch/arm/include/asm/uaccess.h index 89a28680934b..18303bcc9990 100644 --- a/arch/arm/include/asm/uaccess.h +++ b/arch/arm/include/asm/uaccess.h @@ -113,10 +113,11 @@ static inline void __user *__uaccess_mask_range_ptr(const void __user *ptr, unsigned long tmp; asm volatile( + " .syntax unified\n" " sub %1, %3, #1\n" " subs %1, %1, %0\n" " addhs %1, %1, #1\n" - " subhss %1, %1, %2\n" + " subshs %1, %1, %2\n" " movlo %0, #0\n" : "+r" (safe_ptr), "=&r" (tmp) : "r" (size), "r" (current_thread_info()->addr_limit)
Convert the conditional infix to a postfix to make sure this inline assembly is unified syntax. Since gcc assumes non-unified syntax when emitting ARM instructions, make sure to define the syntax as unified. This allows to use LLVM's integrated assembler. Additionally, for GCC ".syntax unified" for inline assembly. When compiling non-Thumb2 GCC always emits a ".syntax divided" at the beginning of the inline assembly which makes the assembler fail. Since GCC 5 there is the -masm-syntax-unified GCC option which make GCC assume unified syntax asm and hence emits ".syntax unified" even in ARM mode. However, the option is broken since GCC version 6 (see GCC PR88648 [1]). Work around by adding ".syntax unified" as part of the inline assembly. [0] https://gcc.gnu.org/onlinedocs/gcc/ARM-Options.html#index-masm-syntax-unified [1] https://gcc.gnu.org/bugzilla/show_bug.cgi?id=88648 Signed-off-by: Stefan Agner <stefan@agner.ch> --- I missed this instance in my previous commits and realized only after running some randconfig. arch/arm/include/asm/uaccess.h | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)