From 80bbb4eda36cf00e13fa49a206b88e80cf2acdc7 Mon Sep 17 00:00:00 2001 From: Sebastian Huber Date: Wed, 8 Jun 2016 08:52:38 +0200 Subject: score: Use builtin for _Bitfield_Find_first_bit() In case the CPU architecture provides no specialized _CPU_Bitfield_Find_first_bit() macro, then use the __builtin_clz() builtin in case __GNUC__ is defined. --- cpukit/score/include/rtems/score/prioritybitmapimpl.h | 2 ++ 1 file changed, 2 insertions(+) diff --git a/cpukit/score/include/rtems/score/prioritybitmapimpl.h b/cpukit/score/include/rtems/score/prioritybitmapimpl.h index 2041a2072d..0082720392 100644 --- a/cpukit/score/include/rtems/score/prioritybitmapimpl.h +++ b/cpukit/score/include/rtems/score/prioritybitmapimpl.h @@ -60,6 +60,8 @@ RTEMS_INLINE_ROUTINE unsigned int _Bitfield_Find_first_bit( #if ( CPU_USE_GENERIC_BITFIELD_CODE == FALSE ) _CPU_Bitfield_Find_first_bit( value, bit_number ); +#elif defined(__GNUC__) + bit_number = __builtin_clz( value ) - __SIZEOF_INT__ * __CHAR_BIT__ + 16; #else if ( value < 0x100 ) { bit_number = _Bitfield_Leading_zeros[ value ] + 8; -- cgit v1.2.3