1*0a6a1f1dSLionel Sambuc /* ===-- powidf2.cpp - Implement __powidf2 ---------------------------------=== 2*0a6a1f1dSLionel Sambuc * 3*0a6a1f1dSLionel Sambuc * The LLVM Compiler Infrastructure 4*0a6a1f1dSLionel Sambuc * 5*0a6a1f1dSLionel Sambuc * This file is dual licensed under the MIT and the University of Illinois Open 6*0a6a1f1dSLionel Sambuc * Source Licenses. See LICENSE.TXT for details. 7*0a6a1f1dSLionel Sambuc * 8*0a6a1f1dSLionel Sambuc * ===----------------------------------------------------------------------=== 9*0a6a1f1dSLionel Sambuc * 10*0a6a1f1dSLionel Sambuc * This file implements __powidf2 for the compiler_rt library. 11*0a6a1f1dSLionel Sambuc * 12*0a6a1f1dSLionel Sambuc * ===----------------------------------------------------------------------=== 13*0a6a1f1dSLionel Sambuc */ 14*0a6a1f1dSLionel Sambuc 15*0a6a1f1dSLionel Sambuc #include "int_lib.h" 16*0a6a1f1dSLionel Sambuc 17*0a6a1f1dSLionel Sambuc /* Returns: a ^ b */ 18*0a6a1f1dSLionel Sambuc 19*0a6a1f1dSLionel Sambuc COMPILER_RT_ABI double __powidf2(double a,si_int b)20*0a6a1f1dSLionel Sambuc__powidf2(double a, si_int b) 21*0a6a1f1dSLionel Sambuc { 22*0a6a1f1dSLionel Sambuc const int recip = b < 0; 23*0a6a1f1dSLionel Sambuc double r = 1; 24*0a6a1f1dSLionel Sambuc while (1) 25*0a6a1f1dSLionel Sambuc { 26*0a6a1f1dSLionel Sambuc if (b & 1) 27*0a6a1f1dSLionel Sambuc r *= a; 28*0a6a1f1dSLionel Sambuc b /= 2; 29*0a6a1f1dSLionel Sambuc if (b == 0) 30*0a6a1f1dSLionel Sambuc break; 31*0a6a1f1dSLionel Sambuc a *= a; 32*0a6a1f1dSLionel Sambuc } 33*0a6a1f1dSLionel Sambuc return recip ? 1/r : r; 34*0a6a1f1dSLionel Sambuc } 35