1// SPDX-License-Identifier: GPL-2.0 2/*---------------------------------------------------------------------------+ 3 | reg_convert.c | 4 | | 5 | Convert register representation. | 6 | | 7 | Copyright (C) 1992,1993,1994,1996,1997 | 8 | W. Metzenthen, 22 Parker St, Ormond, Vic 3163, Australia | 9 | E-mail billm@suburbia.net | 10 | | 11 | | 12 +---------------------------------------------------------------------------*/ 13 14#include "exception.h" 15#include "fpu_emu.h" 16 17int FPU_to_exp16(FPU_REG const *a, FPU_REG *x) 18{ 19 int sign = getsign(a); 20 21 *(long long *)&(x->sigl) = *(const long long *)&(a->sigl); 22 23 /* Set up the exponent as a 16 bit quantity. */ 24 setexponent16(x, exponent(a)); 25 26 if (exponent16(x) == EXP_UNDER) { 27 /* The number is a de-normal or pseudodenormal. */ 28 /* We only deal with the significand and exponent. */ 29 30 if (x->sigh & 0x80000000) { 31 /* Is a pseudodenormal. */ 32 /* This is non-80486 behaviour because the number 33 loses its 'denormal' identity. */ 34 addexponent(x, 1); 35 } else { 36 /* Is a denormal. */ 37 addexponent(x, 1); 38 FPU_normalize_nuo(x); 39 } 40 } 41 42 if (!(x->sigh & 0x80000000)) { 43 EXCEPTION(EX_INTERNAL | 0x180); 44 } 45 46 return sign; 47} 48