1 //===-- powidf2.cpp - Implement __powidf2 ---------------------------------===// 2 // 3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions. 4 // See https://llvm.org/LICENSE.txt for license information. 5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception 6 // 7 //===----------------------------------------------------------------------===// 8 // 9 // This file implements __powidf2 for the compiler_rt library. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #include "int_lib.h" 14 15 // Returns: a ^ b 16 17 COMPILER_RT_ABI double __powidf2(double a, int b) { 18 const int recip = b < 0; 19 double r = 1; 20 while (1) { 21 if (b & 1) 22 r *= a; 23 b /= 2; 24 if (b == 0) 25 break; 26 a *= a; 27 } 28 return recip ? 1 / r : r; 29 } 30