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Diffstat (limited to 'compiler-rt/lib/builtins/ctzti2.c')
-rw-r--r-- | compiler-rt/lib/builtins/ctzti2.c | 29 |
1 files changed, 29 insertions, 0 deletions
diff --git a/compiler-rt/lib/builtins/ctzti2.c b/compiler-rt/lib/builtins/ctzti2.c new file mode 100644 index 000000000000..2a1312c8437d --- /dev/null +++ b/compiler-rt/lib/builtins/ctzti2.c @@ -0,0 +1,29 @@ +//===-- ctzti2.c - Implement __ctzti2 -------------------------------------===// +// +// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. +// See https://llvm.org/LICENSE.txt for license information. +// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception +// +//===----------------------------------------------------------------------===// +// +// This file implements __ctzti2 for the compiler_rt library. +// +//===----------------------------------------------------------------------===// + +#include "int_lib.h" + +#ifdef CRT_HAS_128BIT + +// Returns: the number of trailing 0-bits + +// Precondition: a != 0 + +COMPILER_RT_ABI si_int __ctzti2(ti_int a) { + twords x; + x.all = a; + const di_int f = -(x.s.low == 0); + return __builtin_ctzll((x.s.high & f) | (x.s.low & ~f)) + + ((si_int)f & ((si_int)(sizeof(di_int) * CHAR_BIT))); +} + +#endif // CRT_HAS_128BIT |