[PATCH v2 3/3] ARM: spinlock: use unified assembler language syntax

From: Stefan Agner
Date: Thu Jan 03 2019 - 16:48:13 EST


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.

Signed-off-by: Stefan Agner <stefan@xxxxxxxx>
---
Changes since v1:
- Explicitly use unified syntax for inline assembly


arch/arm/include/asm/spinlock.h | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)

diff --git a/arch/arm/include/asm/spinlock.h b/arch/arm/include/asm/spinlock.h
index 099c78fcf62d..8f009e788ad4 100644
--- a/arch/arm/include/asm/spinlock.h
+++ b/arch/arm/include/asm/spinlock.h
@@ -210,11 +210,12 @@ static inline void arch_read_lock(arch_rwlock_t *rw)

prefetchw(&rw->lock);
__asm__ __volatile__(
+" .syntax unified\n"
"1: ldrex %0, [%2]\n"
" adds %0, %0, #1\n"
" strexpl %1, %0, [%2]\n"
WFE("mi")
-" rsbpls %0, %1, #0\n"
+" rsbspl %0, %1, #0\n"
" bmi 1b"
: "=&r" (tmp), "=&r" (tmp2)
: "r" (&rw->lock)
--
2.20.1