| |
| /* |
| * Copyright (C) 2008-2009 Advanced Micro Devices, Inc. All Rights Reserved. |
| * |
| * This file is part of libacml_mv. |
| * |
| * libacml_mv is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU Lesser General Public |
| * License as published by the Free Software Foundation; either |
| * version 2.1 of the License, or (at your option) any later version. |
| * |
| * libacml_mv is distributed in the hope that it will be useful, |
| * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |
| * Lesser General Public License for more details. |
| * |
| * You should have received a copy of the GNU Lesser General Public |
| * License along with libacml_mv. If not, see |
| * <http://www.gnu.org/licenses/>. |
| * |
| */ |
| |
| |
| #include "../inc/libm_amd.h" |
| #include "../inc/libm_util_amd.h" |
| |
| double FN_PROTOTYPE(modf)(double x, double *iptr) |
| { |
| /* modf splits the argument x into integer and fraction parts, |
| each with the same sign as x. */ |
| |
| |
| long long xexp; |
| unsigned long long ux, ax, mask; |
| |
| GET_BITS_DP64(x, ux); |
| ax = ux & (~SIGNBIT_DP64); |
| |
| if (ax >= 0x4340000000000000) |
| { |
| /* abs(x) is either NaN, infinity, or >= 2^53 */ |
| if (ax > 0x7ff0000000000000) |
| { |
| /* x is NaN */ |
| *iptr = x; |
| return x + x; /* Raise invalid if it is a signalling NaN */ |
| } |
| else |
| { |
| /* x is infinity or large. Return zero with the sign of x */ |
| *iptr = x; |
| PUT_BITS_DP64(ux & SIGNBIT_DP64, x); |
| return x; |
| } |
| } |
| else if (ax < 0x3ff0000000000000) |
| { |
| /* abs(x) < 1.0. Set iptr to zero with the sign of x |
| and return x. */ |
| PUT_BITS_DP64(ux & SIGNBIT_DP64, *iptr); |
| return x; |
| } |
| else |
| { |
| double r; |
| unsigned long long ur; |
| xexp = ((ux & EXPBITS_DP64) >> EXPSHIFTBITS_DP64) - EXPBIAS_DP64; |
| /* Mask out the bits of x that we don't want */ |
| mask = 1; |
| mask = (mask << (EXPSHIFTBITS_DP64 - xexp)) - 1; |
| PUT_BITS_DP64(ux & ~mask, *iptr); |
| r = x - *iptr; |
| GET_BITS_DP64(r, ur); |
| PUT_BITS_DP64(((ux & SIGNBIT_DP64)|ur), r); |
| return r; |
| } |
| |
| } |
| |
| weak_alias (__modf, modf) |