1 /* Copyright (C) 1989-2019 Free Software Foundation, Inc. 2 3 This file is part of GCC. 4 5 GCC is free software; you can redistribute it and/or modify it under 6 the terms of the GNU General Public License as published by the Free 7 Software Foundation; either version 3, or (at your option) any later 8 version. 9 10 GCC is distributed in the hope that it will be useful, but WITHOUT ANY 11 WARRANTY; without even the implied warranty of MERCHANTABILITY or 12 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 13 for more details. 14 15 Under Section 7 of GPL version 3, you are granted additional 16 permissions described in the GCC Runtime Library Exception, version 17 3.1, as published by the Free Software Foundation. 18 19 You should have received a copy of the GNU General Public License and 20 a copy of the GCC Runtime Library Exception along with this program; 21 see the files COPYING3 and COPYING.RUNTIME respectively. If not, see 22 <http://www.gnu.org/licenses/>. */ 23 24 /* This is a temporary specialization of code from libgcc/libgcc2.c. */ 25 26 #include "soft-fp.h" 27 #include "quad-float128.h" 28 29 #define COPYSIGN(x,y) __builtin_copysignf128 (x, y) 30 #define INFINITY __builtin_inff128 () 31 #define FABS __builtin_fabsf128 32 #define isnan __builtin_isnan 33 #define isinf __builtin_isinf 34 #define isfinite __builtin_isfinite 35 36 #if defined(FLOAT128_HW_INSNS) && !defined(__divkc3) 37 #define __divkc3 __divkc3_sw 38 #endif 39 40 TCtype 41 __divkc3 (TFtype a, TFtype b, TFtype c, TFtype d) 42 { 43 TFtype denom, ratio, x, y; 44 TCtype res; 45 46 /* ??? We can get better behavior from logarithmic scaling instead of 47 the division. But that would mean starting to link libgcc against 48 libm. We could implement something akin to ldexp/frexp as gcc builtins 49 fairly easily... */ 50 if (FABS (c) < FABS (d)) 51 { 52 ratio = c / d; 53 denom = (c * ratio) + d; 54 x = ((a * ratio) + b) / denom; 55 y = ((b * ratio) - a) / denom; 56 } 57 else 58 { 59 ratio = d / c; 60 denom = (d * ratio) + c; 61 x = ((b * ratio) + a) / denom; 62 y = (b - (a * ratio)) / denom; 63 } 64 65 /* Recover infinities and zeros that computed as NaN+iNaN; the only cases 66 are nonzero/zero, infinite/finite, and finite/infinite. */ 67 if (isnan (x) && isnan (y)) 68 { 69 if (c == 0.0 && d == 0.0 && (!isnan (a) || !isnan (b))) 70 { 71 x = COPYSIGN (INFINITY, c) * a; 72 y = COPYSIGN (INFINITY, c) * b; 73 } 74 else if ((isinf (a) || isinf (b)) && isfinite (c) && isfinite (d)) 75 { 76 a = COPYSIGN (isinf (a) ? 1 : 0, a); 77 b = COPYSIGN (isinf (b) ? 1 : 0, b); 78 x = INFINITY * (a * c + b * d); 79 y = INFINITY * (b * c - a * d); 80 } 81 else if ((isinf (c) || isinf (d)) && isfinite (a) && isfinite (b)) 82 { 83 c = COPYSIGN (isinf (c) ? 1 : 0, c); 84 d = COPYSIGN (isinf (d) ? 1 : 0, d); 85 x = 0.0 * (a * c + b * d); 86 y = 0.0 * (b * c - a * d); 87 } 88 } 89 90 __real__ res = x; 91 __imag__ res = y; 92 return res; 93 } 94