//===-- ffsti2.c - Implement __ffsti2 -------------------------------------===// // // The LLVM Compiler Infrastructure // // This file is distributed under the University of Illinois Open Source // License. See LICENSE.TXT for details. // //===----------------------------------------------------------------------===// // // This file implements __ffsti2 for the compiler_rt library. // //===----------------------------------------------------------------------===// #if __x86_64 #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. si_int __ffsti2(ti_int a) { twords x; x.all = a; if (x.low == 0) { if (x.high == 0) return 0; return __builtin_ctzll(x.high) + (1 + sizeof(di_int) * CHAR_BIT); } return __builtin_ctzll(x.low) + 1; } #endif