@@ -45,9 +45,7 @@
static inline __attribute_const__ __u16 __fswab16(__u16 val)
{
-#ifdef __HAVE_BUILTIN_BSWAP16__
- return __builtin_bswap16(val);
-#elif defined (__arch_swab16)
+#if defined (__arch_swab16)
return __arch_swab16(val);
#else
return ___constant_swab16(val);
@@ -56,9 +54,7 @@ static inline __attribute_const__ __u16 __fswab16(__u16 val)
static inline __attribute_const__ __u32 __fswab32(__u32 val)
{
-#ifdef __HAVE_BUILTIN_BSWAP32__
- return __builtin_bswap32(val);
-#elif defined(__arch_swab32)
+#if defined(__arch_swab32)
return __arch_swab32(val);
#else
return ___constant_swab32(val);
@@ -67,9 +63,7 @@ static inline __attribute_const__ __u32 __fswab32(__u32 val)
static inline __attribute_const__ __u64 __fswab64(__u64 val)
{
-#ifdef __HAVE_BUILTIN_BSWAP64__
- return __builtin_bswap64(val);
-#elif defined (__arch_swab64)
+#if defined (__arch_swab64)
return __arch_swab64(val);
#elif defined(__SWAB_64_THRU_32__)
__u32 h = val >> 32;
@@ -102,28 +96,40 @@ static inline __attribute_const__ __u32 __fswahb32(__u32 val)
* __swab16 - return a byteswapped 16-bit value
* @x: value to byteswap
*/
+#ifdef __HAVE_BUILTIN_BSWAP16__
+#define __swab16(x) __builtin_bswap16((__u16)(x))
+#else
#define __swab16(x) \
(__builtin_constant_p((__u16)(x)) ? \
___constant_swab16(x) : \
__fswab16(x))
+#endif
/**
* __swab32 - return a byteswapped 32-bit value
* @x: value to byteswap
*/
+#ifdef __HAVE_BUILTIN_BSWAP32__
+#define __swab32(x) __builtin_bswap32((__u32)(x))
+#else
#define __swab32(x) \
(__builtin_constant_p((__u32)(x)) ? \
___constant_swab32(x) : \
__fswab32(x))
+#endif
/**
* __swab64 - return a byteswapped 64-bit value
* @x: value to byteswap
*/
+#ifdef __HAVE_BUILTIN_BSWAP64__
+#define __swab64(x) __builtin_bswap64((__u64)(x))
+#else
#define __swab64(x) \
(__builtin_constant_p((__u64)(x)) ? \
___constant_swab64(x) : \
__fswab64(x))
+#endif
/**
* __swahw32 - return a word-swapped 32-bit value
This is another attempt to avoid a regression in wwn_to_u64() after that started using get_unaligned_be64(), which in turn ran into a bug on gcc-4.9 through 6.1. As part of the problem is how __builtin_constant_p gets evaluated on an argument passed by reference into an inline function, this avoids the use of __builtin_constant_p() for all architectures that set CONFIG_ARCH_USE_BUILTIN_BSWAP. Most architectures do not set ARCH_SUPPORTS_OPTIMIZED_INLINING, which means they probably do not suffer from the problem in the qla2xxx driver, but they might still run into it elsewhere. I have not been able to reproduce the original problem, so I don't know if this patch solves it, but at least it leads to simpler code doing the same thing, so at least there should be no downsides. Please test. Signed-off-by: Arnd Bergmann <arnd@arndb.de>