162306a36Sopenharmony_ci// SPDX-License-Identifier: GPL-2.0-only 262306a36Sopenharmony_ci/* IEEE754 floating point arithmetic 362306a36Sopenharmony_ci * double precision: common utilities 462306a36Sopenharmony_ci */ 562306a36Sopenharmony_ci/* 662306a36Sopenharmony_ci * MIPS floating point support 762306a36Sopenharmony_ci * Copyright (C) 1994-2000 Algorithmics Ltd. 862306a36Sopenharmony_ci */ 962306a36Sopenharmony_ci 1062306a36Sopenharmony_ci#include "ieee754dp.h" 1162306a36Sopenharmony_ci 1262306a36Sopenharmony_ciunion ieee754dp ieee754dp_fint(int x) 1362306a36Sopenharmony_ci{ 1462306a36Sopenharmony_ci u64 xm; 1562306a36Sopenharmony_ci int xe; 1662306a36Sopenharmony_ci int xs; 1762306a36Sopenharmony_ci 1862306a36Sopenharmony_ci ieee754_clearcx(); 1962306a36Sopenharmony_ci 2062306a36Sopenharmony_ci if (x == 0) 2162306a36Sopenharmony_ci return ieee754dp_zero(0); 2262306a36Sopenharmony_ci if (x == 1 || x == -1) 2362306a36Sopenharmony_ci return ieee754dp_one(x < 0); 2462306a36Sopenharmony_ci if (x == 10 || x == -10) 2562306a36Sopenharmony_ci return ieee754dp_ten(x < 0); 2662306a36Sopenharmony_ci 2762306a36Sopenharmony_ci xs = (x < 0); 2862306a36Sopenharmony_ci if (xs) { 2962306a36Sopenharmony_ci if (x == (1 << 31)) 3062306a36Sopenharmony_ci xm = ((unsigned) 1 << 31); /* max neg can't be safely negated */ 3162306a36Sopenharmony_ci else 3262306a36Sopenharmony_ci xm = -x; 3362306a36Sopenharmony_ci } else { 3462306a36Sopenharmony_ci xm = x; 3562306a36Sopenharmony_ci } 3662306a36Sopenharmony_ci 3762306a36Sopenharmony_ci /* normalize - result can never be inexact or overflow */ 3862306a36Sopenharmony_ci xe = DP_FBITS; 3962306a36Sopenharmony_ci while ((xm >> DP_FBITS) == 0) { 4062306a36Sopenharmony_ci xm <<= 1; 4162306a36Sopenharmony_ci xe--; 4262306a36Sopenharmony_ci } 4362306a36Sopenharmony_ci return builddp(xs, xe + DP_EBIAS, xm & ~DP_HIDDEN_BIT); 4462306a36Sopenharmony_ci} 45