66 lines
1.7 KiB
C
66 lines
1.7 KiB
C
/* 32-bit floating point to 128-bit floating point.
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Copyright (C) 1997 Free Software Foundation, Inc.
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This file is part of the GNU C Library.
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The GNU C Library is free software; you can redistribute it and/or
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modify it under the terms of the GNU Library General Public License as
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published by the Free Software Foundation; either version 2 of the
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License, or (at your option) any later version.
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The GNU C Library is distributed in the hope that it will be useful,
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but WITHOUT ANY WARRANTY; without even the implied warranty of
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MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
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Library General Public License for more details.
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You should have received a copy of the GNU Library General Public
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License along with the GNU C Library; see the file COPYING.LIB. If not,
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write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
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Boston, MA 02111-1307, USA. */
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#include <quad_float.h>
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/* long double _q_stoq(float a);
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Convert 'a' to long double. Don't raise exceptions.
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*/
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void
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__q_stoq(unsigned long long result[2], float a)
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{
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unsigned ux, rx;
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union {
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float d;
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unsigned u;
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} u;
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u.d = a;
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result[1] = 0;
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result[0] = u.u << 32-7;
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/* correct exponent bias */
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rx = ((int)u.u >> 23 & 0x80ff) + 16383-127;
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ux = u.u >> 23 & 0xff;
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if (ux == 0)
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{
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if ((u.u & 0x7fffffff) == 0)
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{
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/* +0.0 or -0.0. */
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rx &= 0x8000;
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}
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else
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{
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/* Denormalised number. Renormalise. */
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unsigned um = u.u & 0x007fffff;
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int cs = cntlzw(um) - 9 + 1;
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rx -= cs;
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um <<= cs;
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result[0] = um << 32-7;
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}
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}
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else if (ux == 0xff)
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{
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/* Inf or NaN. */
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rx |= 0x7fff;
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}
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*(unsigned short *)result = rx;
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}
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