1b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project 2b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project/* @(#)s_modf.c 1.3 95/01/18 */ 3b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project/* 4b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project * ==================================================== 5b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved. 6b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project * 7b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project * Developed at SunSoft, a Sun Microsystems, Inc. business. 8b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project * Permission to use, copy, modify, and distribute this 9b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project * software is freely granted, provided that this notice 10b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project * is preserved. 11b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project * ==================================================== 12b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project */ 13b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project 14b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project/* 15b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project * ieee_modf(double x, double *iptr) 16b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project * return fraction part of x, and return x's integral part in *iptr. 17b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project * Method: 18b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project * Bit twiddling. 19b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project * 20b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project * Exception: 21b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project * No exception. 22b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project */ 23b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project 24b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project#include "fdlibm.h" 25b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project 26b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project#ifdef __STDC__ 27b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Projectstatic const double one = 1.0; 28b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project#else 29b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Projectstatic double one = 1.0; 30b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project#endif 31b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project 32b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project#ifdef __STDC__ 33b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project double ieee_modf(double x, double *iptr) 34b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project#else 35b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project double ieee_modf(x, iptr) 36b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project double x,*iptr; 37b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project#endif 38b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project{ 39b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project int i0,i1,j0; 40b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project unsigned i; 41b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project i0 = __HI(x); /* high x */ 42b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project i1 = __LO(x); /* low x */ 43b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project j0 = ((i0>>20)&0x7ff)-0x3ff; /* exponent of x */ 44b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project if(j0<20) { /* integer part in high x */ 45b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project if(j0<0) { /* |x|<1 */ 46b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project __HIp(iptr) = i0&0x80000000; 47b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project __LOp(iptr) = 0; /* *iptr = +-0 */ 48b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project return x; 49b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project } else { 50b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project i = (0x000fffff)>>j0; 51b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project if(((i0&i)|i1)==0) { /* x is integral */ 52b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project *iptr = x; 53b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project __HI(x) &= 0x80000000; 54b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project __LO(x) = 0; /* return +-0 */ 55b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project return x; 56b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project } else { 57b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project __HIp(iptr) = i0&(~i); 58b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project __LOp(iptr) = 0; 59b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project return x - *iptr; 60b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project } 61b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project } 62b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project } else if (j0>51) { /* no fraction part */ 63b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project *iptr = x*one; 64b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project __HI(x) &= 0x80000000; 65b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project __LO(x) = 0; /* return +-0 */ 66b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project return x; 67b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project } else { /* fraction part in low x */ 68b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project i = ((unsigned)(0xffffffff))>>(j0-20); 69b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project if((i1&i)==0) { /* x is integral */ 70b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project *iptr = x; 71b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project __HI(x) &= 0x80000000; 72b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project __LO(x) = 0; /* return +-0 */ 73b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project return x; 74b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project } else { 75b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project __HIp(iptr) = i0; 76b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project __LOp(iptr) = i1&(~i); 77b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project return x - *iptr; 78b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project } 79b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project } 80b07e1d9fd8d9e4e03698e0bd9bf77154c5390326The Android Open Source Project} 81