[PATCH] ia64: Rewrite atomic_add and atomic_sub

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From: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>

Force __builtin_constant_p to evaluate whether the argument to atomic_add
& atomic_sub is constant in the front-end before optimisations which
can lead GCC to output a call to __bad_increment_for_ia64_fetch_and_add().

See GCC bugzilla 83653.

Signed-off-by: Jakub Jelinek <jakub@xxxxxxxxxx>
Signed-off-by: Matthew Wilcox <mawilcox@xxxxxxxxxxxxx>
---
 arch/ia64/include/asm/atomic.h | 37 +++++++++++++++++++------------------
 1 file changed, 19 insertions(+), 18 deletions(-)

diff --git a/arch/ia64/include/asm/atomic.h b/arch/ia64/include/asm/atomic.h
index 28e02c99be6d..762eeb0fcc1d 100644
--- a/arch/ia64/include/asm/atomic.h
+++ b/arch/ia64/include/asm/atomic.h
@@ -65,29 +65,30 @@ ia64_atomic_fetch_##op (int i, atomic_t *v)				\
 ATOMIC_OPS(add, +)
 ATOMIC_OPS(sub, -)
 
-#define atomic_add_return(i,v)						\
+#ifdef __OPTIMIZE__
+#define __ia64_atomic_const(i)	__builtin_constant_p(i) ?		\
+		((i) == 1 || (i) == 4 || (i) == 8 || (i) == 16 ||	\
+		 (i) == -1 || (i) == -4 || (i) == -8 || (i) == -16) : 0
+
+#define atomic_add_return(i, v)						\
 ({									\
-	int __ia64_aar_i = (i);						\
-	(__builtin_constant_p(i)					\
-	 && (   (__ia64_aar_i ==  1) || (__ia64_aar_i ==   4)		\
-	     || (__ia64_aar_i ==  8) || (__ia64_aar_i ==  16)		\
-	     || (__ia64_aar_i == -1) || (__ia64_aar_i ==  -4)		\
-	     || (__ia64_aar_i == -8) || (__ia64_aar_i == -16)))		\
-		? ia64_fetch_and_add(__ia64_aar_i, &(v)->counter)	\
-		: ia64_atomic_add(__ia64_aar_i, v);			\
+	int __i = (i);							\
+	static const int __ia64_atomic_p = __ia64_atomic_const(i);	\
+	__ia64_atomic_p ? ia64_fetch_and_add(__i, &(v)->counter) :	\
+				ia64_atomic_add(__i, v);		\
 })
 
-#define atomic_sub_return(i,v)						\
+#define atomic_sub_return(i, v)						\
 ({									\
-	int __ia64_asr_i = (i);						\
-	(__builtin_constant_p(i)					\
-	 && (   (__ia64_asr_i ==   1) || (__ia64_asr_i ==   4)		\
-	     || (__ia64_asr_i ==   8) || (__ia64_asr_i ==  16)		\
-	     || (__ia64_asr_i ==  -1) || (__ia64_asr_i ==  -4)		\
-	     || (__ia64_asr_i ==  -8) || (__ia64_asr_i == -16)))	\
-		? ia64_fetch_and_add(-__ia64_asr_i, &(v)->counter)	\
-		: ia64_atomic_sub(__ia64_asr_i, v);			\
+	int __i = (i);							\
+	static const int __ia64_atomic_p = __ia64_atomic_const(i);	\
+	__ia64_atomic_p ? ia64_fetch_and_add(-__i, &(v)->counter) :	\
+				ia64_atomic_sub(__i, v);		\
 })
+#else
+#define atomic_add_return(i, v)	ia64_atomic_add(i, v)
+#define atomic_sub_return(i, v)	ia64_atomic_sub(i, v)
+#endif
 
 #define atomic_fetch_add(i,v)						\
 ({									\
-- 
2.15.1

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