diff options
Diffstat (limited to 'lib/builtins/ffssi2.c')
-rw-r--r-- | lib/builtins/ffssi2.c | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/lib/builtins/ffssi2.c b/lib/builtins/ffssi2.c new file mode 100644 index 000000000000..e5180eff5e08 --- /dev/null +++ b/lib/builtins/ffssi2.c @@ -0,0 +1,29 @@ +/* ===-- ffssi2.c - Implement __ffssi2 -------------------------------------=== + * + * The LLVM Compiler Infrastructure + * + * This file is dual licensed under the MIT and the University of Illinois Open + * Source Licenses. See LICENSE.TXT for details. + * + * ===----------------------------------------------------------------------=== + * + * This file implements __ffssi2 for the compiler_rt library. + * + * ===----------------------------------------------------------------------=== + */ + +#include "int_lib.h" + +/* Returns: the index of the least significant 1-bit in a, or + * the value zero if a is zero. The least significant bit is index one. + */ + +COMPILER_RT_ABI si_int +__ffssi2(si_int a) +{ + if (a == 0) + { + return 0; + } + return __builtin_ctz(a) + 1; +} |