c9ab9ae440
These bits are taken from the FSF anoncvs repo on 1-Feb-2002 08:20 PST.
1372 lines
29 KiB
C
1372 lines
29 KiB
C
/* This is a software floating point library which can be used
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for targets without hardware floating point.
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Copyright (C) 1994, 1995, 1996, 1997, 1998, 2000, 2001
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Free Software Foundation, Inc.
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This file is free software; you can redistribute it and/or modify it
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under the terms of the GNU General Public License as published by the
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Free Software Foundation; either version 2, or (at your option) any
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later version.
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In addition to the permissions in the GNU General Public License, the
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Free Software Foundation gives you unlimited permission to link the
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compiled version of this file with other programs, and to distribute
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those programs without any restriction coming from the use of this
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file. (The General Public License restrictions do apply in other
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respects; for example, they cover modification of the file, and
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distribution when not linked into another program.)
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This file is distributed in the hope that it will be useful, but
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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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General Public License for more details.
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You should have received a copy of the GNU General Public License
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along with this program; see the file COPYING. If not, write to
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the Free Software Foundation, 59 Temple Place - Suite 330,
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Boston, MA 02111-1307, USA. */
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/* As a special exception, if you link this library with other files,
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some of which are compiled with GCC, to produce an executable,
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this library does not by itself cause the resulting executable
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to be covered by the GNU General Public License.
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This exception does not however invalidate any other reasons why
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the executable file might be covered by the GNU General Public License. */
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/* This implements IEEE 754 format arithmetic, but does not provide a
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mechanism for setting the rounding mode, or for generating or handling
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exceptions.
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The original code by Steve Chamberlain, hacked by Mark Eichin and Jim
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Wilson, all of Cygnus Support. */
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/* The intended way to use this file is to make two copies, add `#define FLOAT'
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to one copy, then compile both copies and add them to libgcc.a. */
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#include "tconfig.h"
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#include "fp-bit.h"
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/* The following macros can be defined to change the behaviour of this file:
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FLOAT: Implement a `float', aka SFmode, fp library. If this is not
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defined, then this file implements a `double', aka DFmode, fp library.
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FLOAT_ONLY: Used with FLOAT, to implement a `float' only library, i.e.
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don't include float->double conversion which requires the double library.
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This is useful only for machines which can't support doubles, e.g. some
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8-bit processors.
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CMPtype: Specify the type that floating point compares should return.
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This defaults to SItype, aka int.
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US_SOFTWARE_GOFAST: This makes all entry points use the same names as the
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US Software goFast library.
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_DEBUG_BITFLOAT: This makes debugging the code a little easier, by adding
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two integers to the FLO_union_type.
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NO_DENORMALS: Disable handling of denormals.
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NO_NANS: Disable nan and infinity handling
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SMALL_MACHINE: Useful when operations on QIs and HIs are faster
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than on an SI */
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/* We don't currently support extended floats (long doubles) on machines
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without hardware to deal with them.
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These stubs are just to keep the linker from complaining about unresolved
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references which can be pulled in from libio & libstdc++, even if the
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user isn't using long doubles. However, they may generate an unresolved
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external to abort if abort is not used by the function, and the stubs
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are referenced from within libc, since libgcc goes before and after the
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system library. */
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#ifdef EXTENDED_FLOAT_STUBS
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__truncxfsf2 (){ abort(); }
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__extendsfxf2 (){ abort(); }
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__addxf3 (){ abort(); }
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__divxf3 (){ abort(); }
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__eqxf2 (){ abort(); }
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__extenddfxf2 (){ abort(); }
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__gtxf2 (){ abort(); }
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__lexf2 (){ abort(); }
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__ltxf2 (){ abort(); }
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__mulxf3 (){ abort(); }
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__negxf2 (){ abort(); }
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__nexf2 (){ abort(); }
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__subxf3 (){ abort(); }
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__truncxfdf2 (){ abort(); }
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__trunctfsf2 (){ abort(); }
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__extendsftf2 (){ abort(); }
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__addtf3 (){ abort(); }
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__divtf3 (){ abort(); }
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__eqtf2 (){ abort(); }
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__extenddftf2 (){ abort(); }
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__gttf2 (){ abort(); }
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__letf2 (){ abort(); }
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__lttf2 (){ abort(); }
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__multf3 (){ abort(); }
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__negtf2 (){ abort(); }
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__netf2 (){ abort(); }
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__subtf3 (){ abort(); }
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__trunctfdf2 (){ abort(); }
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__gexf2 (){ abort(); }
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__fixxfsi (){ abort(); }
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__floatsixf (){ abort(); }
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#else /* !EXTENDED_FLOAT_STUBS, rest of file */
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/* IEEE "special" number predicates */
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#ifdef NO_NANS
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#define nan() 0
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#define isnan(x) 0
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#define isinf(x) 0
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#else
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#if defined L_thenan_sf
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const fp_number_type __thenan_sf = { CLASS_SNAN, 0, 0, {(fractype) 0} };
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#elif defined L_thenan_df
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const fp_number_type __thenan_df = { CLASS_SNAN, 0, 0, {(fractype) 0} };
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#elif defined FLOAT
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extern const fp_number_type __thenan_sf;
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#else
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extern const fp_number_type __thenan_df;
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#endif
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INLINE
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static fp_number_type *
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nan (void)
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{
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/* Discard the const qualifier... */
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#ifdef FLOAT
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return (fp_number_type *) (& __thenan_sf);
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#else
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return (fp_number_type *) (& __thenan_df);
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#endif
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}
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INLINE
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static int
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isnan ( fp_number_type * x)
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{
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return x->class == CLASS_SNAN || x->class == CLASS_QNAN;
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}
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INLINE
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static int
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isinf ( fp_number_type * x)
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{
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return x->class == CLASS_INFINITY;
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}
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#endif /* NO_NANS */
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INLINE
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static int
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iszero ( fp_number_type * x)
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{
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return x->class == CLASS_ZERO;
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}
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INLINE
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static void
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flip_sign ( fp_number_type * x)
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{
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x->sign = !x->sign;
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}
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extern FLO_type pack_d ( fp_number_type * );
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#if defined(L_pack_df) || defined(L_pack_sf)
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FLO_type
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pack_d ( fp_number_type * src)
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{
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FLO_union_type dst;
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fractype fraction = src->fraction.ll; /* wasn't unsigned before? */
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int sign = src->sign;
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int exp = 0;
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if (isnan (src))
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{
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exp = EXPMAX;
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if (src->class == CLASS_QNAN || 1)
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{
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fraction |= QUIET_NAN;
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}
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}
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else if (isinf (src))
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{
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exp = EXPMAX;
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fraction = 0;
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}
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else if (iszero (src))
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{
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exp = 0;
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fraction = 0;
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}
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else if (fraction == 0)
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{
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exp = 0;
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}
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else
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{
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if (src->normal_exp < NORMAL_EXPMIN)
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{
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/* This number's exponent is too low to fit into the bits
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available in the number, so we'll store 0 in the exponent and
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shift the fraction to the right to make up for it. */
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int shift = NORMAL_EXPMIN - src->normal_exp;
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exp = 0;
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if (shift > FRAC_NBITS - NGARDS)
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{
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/* No point shifting, since it's more that 64 out. */
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fraction = 0;
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}
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else
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{
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int lowbit = (fraction & (((fractype)1 << shift) - 1)) ? 1 : 0;
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fraction = (fraction >> shift) | lowbit;
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}
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if ((fraction & GARDMASK) == GARDMSB)
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{
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if ((fraction & (1 << NGARDS)))
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fraction += GARDROUND + 1;
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}
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else
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{
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/* Add to the guards to round up. */
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fraction += GARDROUND;
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}
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/* Perhaps the rounding means we now need to change the
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exponent, because the fraction is no longer denormal. */
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if (fraction >= IMPLICIT_1)
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{
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exp += 1;
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}
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fraction >>= NGARDS;
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}
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else if (src->normal_exp > EXPBIAS)
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{
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exp = EXPMAX;
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fraction = 0;
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}
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else
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{
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exp = src->normal_exp + EXPBIAS;
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/* IF the gard bits are the all zero, but the first, then we're
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half way between two numbers, choose the one which makes the
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lsb of the answer 0. */
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if ((fraction & GARDMASK) == GARDMSB)
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{
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if (fraction & (1 << NGARDS))
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fraction += GARDROUND + 1;
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}
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else
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{
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/* Add a one to the guards to round up */
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fraction += GARDROUND;
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}
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if (fraction >= IMPLICIT_2)
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{
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fraction >>= 1;
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exp += 1;
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}
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fraction >>= NGARDS;
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}
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}
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/* We previously used bitfields to store the number, but this doesn't
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handle little/big endian systems conveniently, so use shifts and
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masks */
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#ifdef FLOAT_BIT_ORDER_MISMATCH
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dst.bits.fraction = fraction;
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dst.bits.exp = exp;
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dst.bits.sign = sign;
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#else
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dst.value_raw = fraction & ((((fractype)1) << FRACBITS) - (fractype)1);
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dst.value_raw |= ((fractype) (exp & ((1 << EXPBITS) - 1))) << FRACBITS;
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dst.value_raw |= ((fractype) (sign & 1)) << (FRACBITS | EXPBITS);
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#endif
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#if defined(FLOAT_WORD_ORDER_MISMATCH) && !defined(FLOAT)
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{
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halffractype tmp = dst.words[0];
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dst.words[0] = dst.words[1];
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dst.words[1] = tmp;
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}
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#endif
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return dst.value;
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}
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#endif
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#if defined(L_unpack_df) || defined(L_unpack_sf)
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void
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unpack_d (FLO_union_type * src, fp_number_type * dst)
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{
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/* We previously used bitfields to store the number, but this doesn't
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handle little/big endian systems conveniently, so use shifts and
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masks */
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fractype fraction;
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int exp;
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int sign;
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#if defined(FLOAT_WORD_ORDER_MISMATCH) && !defined(FLOAT)
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FLO_union_type swapped;
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swapped.words[0] = src->words[1];
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swapped.words[1] = src->words[0];
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src = &swapped;
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#endif
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#ifdef FLOAT_BIT_ORDER_MISMATCH
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fraction = src->bits.fraction;
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exp = src->bits.exp;
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sign = src->bits.sign;
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#else
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fraction = src->value_raw & ((((fractype)1) << FRACBITS) - (fractype)1);
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exp = ((int)(src->value_raw >> FRACBITS)) & ((1 << EXPBITS) - 1);
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sign = ((int)(src->value_raw >> (FRACBITS + EXPBITS))) & 1;
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#endif
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dst->sign = sign;
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if (exp == 0)
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{
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/* Hmm. Looks like 0 */
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if (fraction == 0
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#ifdef NO_DENORMALS
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|| 1
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#endif
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)
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{
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/* tastes like zero */
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dst->class = CLASS_ZERO;
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}
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else
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{
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/* Zero exponent with non zero fraction - it's denormalized,
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so there isn't a leading implicit one - we'll shift it so
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it gets one. */
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dst->normal_exp = exp - EXPBIAS + 1;
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fraction <<= NGARDS;
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dst->class = CLASS_NUMBER;
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#if 1
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while (fraction < IMPLICIT_1)
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{
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fraction <<= 1;
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dst->normal_exp--;
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}
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#endif
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dst->fraction.ll = fraction;
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}
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}
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else if (exp == EXPMAX)
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{
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/* Huge exponent*/
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if (fraction == 0)
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{
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/* Attached to a zero fraction - means infinity */
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dst->class = CLASS_INFINITY;
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}
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else
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{
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/* Non zero fraction, means nan */
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if (fraction & QUIET_NAN)
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{
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dst->class = CLASS_QNAN;
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}
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else
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{
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dst->class = CLASS_SNAN;
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}
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/* Keep the fraction part as the nan number */
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dst->fraction.ll = fraction;
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}
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}
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else
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{
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/* Nothing strange about this number */
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dst->normal_exp = exp - EXPBIAS;
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dst->class = CLASS_NUMBER;
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dst->fraction.ll = (fraction << NGARDS) | IMPLICIT_1;
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}
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}
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#endif /* L_unpack_df || L_unpack_sf */
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#if defined(L_addsub_sf) || defined(L_addsub_df)
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static fp_number_type *
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_fpadd_parts (fp_number_type * a,
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fp_number_type * b,
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fp_number_type * tmp)
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{
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intfrac tfraction;
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/* Put commonly used fields in local variables. */
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int a_normal_exp;
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int b_normal_exp;
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fractype a_fraction;
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fractype b_fraction;
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if (isnan (a))
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{
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return a;
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}
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if (isnan (b))
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{
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return b;
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}
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if (isinf (a))
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{
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/* Adding infinities with opposite signs yields a NaN. */
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if (isinf (b) && a->sign != b->sign)
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return nan ();
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return a;
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}
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if (isinf (b))
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{
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return b;
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}
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if (iszero (b))
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{
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if (iszero (a))
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{
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*tmp = *a;
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tmp->sign = a->sign & b->sign;
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return tmp;
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}
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return a;
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}
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if (iszero (a))
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{
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return b;
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}
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/* Got two numbers. shift the smaller and increment the exponent till
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they're the same */
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{
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int diff;
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a_normal_exp = a->normal_exp;
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b_normal_exp = b->normal_exp;
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a_fraction = a->fraction.ll;
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b_fraction = b->fraction.ll;
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diff = a_normal_exp - b_normal_exp;
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if (diff < 0)
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diff = -diff;
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if (diff < FRAC_NBITS)
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{
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/* ??? This does shifts one bit at a time. Optimize. */
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while (a_normal_exp > b_normal_exp)
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{
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b_normal_exp++;
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LSHIFT (b_fraction);
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}
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while (b_normal_exp > a_normal_exp)
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{
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a_normal_exp++;
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LSHIFT (a_fraction);
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}
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}
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else
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{
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/* Somethings's up.. choose the biggest */
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if (a_normal_exp > b_normal_exp)
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{
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b_normal_exp = a_normal_exp;
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b_fraction = 0;
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}
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else
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{
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a_normal_exp = b_normal_exp;
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a_fraction = 0;
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}
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}
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}
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if (a->sign != b->sign)
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{
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if (a->sign)
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{
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tfraction = -a_fraction + b_fraction;
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}
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else
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{
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tfraction = a_fraction - b_fraction;
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}
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if (tfraction >= 0)
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{
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tmp->sign = 0;
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tmp->normal_exp = a_normal_exp;
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tmp->fraction.ll = tfraction;
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}
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else
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{
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tmp->sign = 1;
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tmp->normal_exp = a_normal_exp;
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tmp->fraction.ll = -tfraction;
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}
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|
/* and renormalize it */
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while (tmp->fraction.ll < IMPLICIT_1 && tmp->fraction.ll)
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{
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tmp->fraction.ll <<= 1;
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tmp->normal_exp--;
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}
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}
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else
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{
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tmp->sign = a->sign;
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tmp->normal_exp = a_normal_exp;
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tmp->fraction.ll = a_fraction + b_fraction;
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}
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tmp->class = CLASS_NUMBER;
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/* Now the fraction is added, we have to shift down to renormalize the
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number */
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if (tmp->fraction.ll >= IMPLICIT_2)
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{
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LSHIFT (tmp->fraction.ll);
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tmp->normal_exp++;
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}
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return tmp;
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}
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|
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FLO_type
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add (FLO_type arg_a, FLO_type arg_b)
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|
{
|
|
fp_number_type a;
|
|
fp_number_type b;
|
|
fp_number_type tmp;
|
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fp_number_type *res;
|
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FLO_union_type au, bu;
|
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|
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au.value = arg_a;
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bu.value = arg_b;
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unpack_d (&au, &a);
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unpack_d (&bu, &b);
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res = _fpadd_parts (&a, &b, &tmp);
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return pack_d (res);
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}
|
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|
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FLO_type
|
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sub (FLO_type arg_a, FLO_type arg_b)
|
|
{
|
|
fp_number_type a;
|
|
fp_number_type b;
|
|
fp_number_type tmp;
|
|
fp_number_type *res;
|
|
FLO_union_type au, bu;
|
|
|
|
au.value = arg_a;
|
|
bu.value = arg_b;
|
|
|
|
unpack_d (&au, &a);
|
|
unpack_d (&bu, &b);
|
|
|
|
b.sign ^= 1;
|
|
|
|
res = _fpadd_parts (&a, &b, &tmp);
|
|
|
|
return pack_d (res);
|
|
}
|
|
#endif /* L_addsub_sf || L_addsub_df */
|
|
|
|
#if defined(L_mul_sf) || defined(L_mul_df)
|
|
static INLINE fp_number_type *
|
|
_fpmul_parts ( fp_number_type * a,
|
|
fp_number_type * b,
|
|
fp_number_type * tmp)
|
|
{
|
|
fractype low = 0;
|
|
fractype high = 0;
|
|
|
|
if (isnan (a))
|
|
{
|
|
a->sign = a->sign != b->sign;
|
|
return a;
|
|
}
|
|
if (isnan (b))
|
|
{
|
|
b->sign = a->sign != b->sign;
|
|
return b;
|
|
}
|
|
if (isinf (a))
|
|
{
|
|
if (iszero (b))
|
|
return nan ();
|
|
a->sign = a->sign != b->sign;
|
|
return a;
|
|
}
|
|
if (isinf (b))
|
|
{
|
|
if (iszero (a))
|
|
{
|
|
return nan ();
|
|
}
|
|
b->sign = a->sign != b->sign;
|
|
return b;
|
|
}
|
|
if (iszero (a))
|
|
{
|
|
a->sign = a->sign != b->sign;
|
|
return a;
|
|
}
|
|
if (iszero (b))
|
|
{
|
|
b->sign = a->sign != b->sign;
|
|
return b;
|
|
}
|
|
|
|
/* Calculate the mantissa by multiplying both numbers to get a
|
|
twice-as-wide number. */
|
|
{
|
|
#if defined(NO_DI_MODE)
|
|
{
|
|
fractype x = a->fraction.ll;
|
|
fractype ylow = b->fraction.ll;
|
|
fractype yhigh = 0;
|
|
int bit;
|
|
|
|
/* ??? This does multiplies one bit at a time. Optimize. */
|
|
for (bit = 0; bit < FRAC_NBITS; bit++)
|
|
{
|
|
int carry;
|
|
|
|
if (x & 1)
|
|
{
|
|
carry = (low += ylow) < ylow;
|
|
high += yhigh + carry;
|
|
}
|
|
yhigh <<= 1;
|
|
if (ylow & FRACHIGH)
|
|
{
|
|
yhigh |= 1;
|
|
}
|
|
ylow <<= 1;
|
|
x >>= 1;
|
|
}
|
|
}
|
|
#elif defined(FLOAT)
|
|
/* Multiplying two USIs to get a UDI, we're safe. */
|
|
{
|
|
UDItype answer = (UDItype)a->fraction.ll * (UDItype)b->fraction.ll;
|
|
|
|
high = answer >> BITS_PER_SI;
|
|
low = answer;
|
|
}
|
|
#else
|
|
/* fractype is DImode, but we need the result to be twice as wide.
|
|
Assuming a widening multiply from DImode to TImode is not
|
|
available, build one by hand. */
|
|
{
|
|
USItype nl = a->fraction.ll;
|
|
USItype nh = a->fraction.ll >> BITS_PER_SI;
|
|
USItype ml = b->fraction.ll;
|
|
USItype mh = b->fraction.ll >> BITS_PER_SI;
|
|
UDItype pp_ll = (UDItype) ml * nl;
|
|
UDItype pp_hl = (UDItype) mh * nl;
|
|
UDItype pp_lh = (UDItype) ml * nh;
|
|
UDItype pp_hh = (UDItype) mh * nh;
|
|
UDItype res2 = 0;
|
|
UDItype res0 = 0;
|
|
UDItype ps_hh__ = pp_hl + pp_lh;
|
|
if (ps_hh__ < pp_hl)
|
|
res2 += (UDItype)1 << BITS_PER_SI;
|
|
pp_hl = (UDItype)(USItype)ps_hh__ << BITS_PER_SI;
|
|
res0 = pp_ll + pp_hl;
|
|
if (res0 < pp_ll)
|
|
res2++;
|
|
res2 += (ps_hh__ >> BITS_PER_SI) + pp_hh;
|
|
high = res2;
|
|
low = res0;
|
|
}
|
|
#endif
|
|
}
|
|
|
|
tmp->normal_exp = a->normal_exp + b->normal_exp;
|
|
tmp->sign = a->sign != b->sign;
|
|
#ifdef FLOAT
|
|
tmp->normal_exp += 2; /* ??????????????? */
|
|
#else
|
|
tmp->normal_exp += 4; /* ??????????????? */
|
|
#endif
|
|
while (high >= IMPLICIT_2)
|
|
{
|
|
tmp->normal_exp++;
|
|
if (high & 1)
|
|
{
|
|
low >>= 1;
|
|
low |= FRACHIGH;
|
|
}
|
|
high >>= 1;
|
|
}
|
|
while (high < IMPLICIT_1)
|
|
{
|
|
tmp->normal_exp--;
|
|
|
|
high <<= 1;
|
|
if (low & FRACHIGH)
|
|
high |= 1;
|
|
low <<= 1;
|
|
}
|
|
/* rounding is tricky. if we only round if it won't make us round later. */
|
|
#if 0
|
|
if (low & FRACHIGH2)
|
|
{
|
|
if (((high & GARDMASK) != GARDMSB)
|
|
&& (((high + 1) & GARDMASK) == GARDMSB))
|
|
{
|
|
/* don't round, it gets done again later. */
|
|
}
|
|
else
|
|
{
|
|
high++;
|
|
}
|
|
}
|
|
#endif
|
|
if ((high & GARDMASK) == GARDMSB)
|
|
{
|
|
if (high & (1 << NGARDS))
|
|
{
|
|
/* half way, so round to even */
|
|
high += GARDROUND + 1;
|
|
}
|
|
else if (low)
|
|
{
|
|
/* but we really weren't half way */
|
|
high += GARDROUND + 1;
|
|
}
|
|
}
|
|
tmp->fraction.ll = high;
|
|
tmp->class = CLASS_NUMBER;
|
|
return tmp;
|
|
}
|
|
|
|
FLO_type
|
|
multiply (FLO_type arg_a, FLO_type arg_b)
|
|
{
|
|
fp_number_type a;
|
|
fp_number_type b;
|
|
fp_number_type tmp;
|
|
fp_number_type *res;
|
|
FLO_union_type au, bu;
|
|
|
|
au.value = arg_a;
|
|
bu.value = arg_b;
|
|
|
|
unpack_d (&au, &a);
|
|
unpack_d (&bu, &b);
|
|
|
|
res = _fpmul_parts (&a, &b, &tmp);
|
|
|
|
return pack_d (res);
|
|
}
|
|
#endif /* L_mul_sf || L_mul_df */
|
|
|
|
#if defined(L_div_sf) || defined(L_div_df)
|
|
static INLINE fp_number_type *
|
|
_fpdiv_parts (fp_number_type * a,
|
|
fp_number_type * b)
|
|
{
|
|
fractype bit;
|
|
fractype numerator;
|
|
fractype denominator;
|
|
fractype quotient;
|
|
|
|
if (isnan (a))
|
|
{
|
|
return a;
|
|
}
|
|
if (isnan (b))
|
|
{
|
|
return b;
|
|
}
|
|
|
|
a->sign = a->sign ^ b->sign;
|
|
|
|
if (isinf (a) || iszero (a))
|
|
{
|
|
if (a->class == b->class)
|
|
return nan ();
|
|
return a;
|
|
}
|
|
|
|
if (isinf (b))
|
|
{
|
|
a->fraction.ll = 0;
|
|
a->normal_exp = 0;
|
|
return a;
|
|
}
|
|
if (iszero (b))
|
|
{
|
|
a->class = CLASS_INFINITY;
|
|
return a;
|
|
}
|
|
|
|
/* Calculate the mantissa by multiplying both 64bit numbers to get a
|
|
128 bit number */
|
|
{
|
|
/* quotient =
|
|
( numerator / denominator) * 2^(numerator exponent - denominator exponent)
|
|
*/
|
|
|
|
a->normal_exp = a->normal_exp - b->normal_exp;
|
|
numerator = a->fraction.ll;
|
|
denominator = b->fraction.ll;
|
|
|
|
if (numerator < denominator)
|
|
{
|
|
/* Fraction will be less than 1.0 */
|
|
numerator *= 2;
|
|
a->normal_exp--;
|
|
}
|
|
bit = IMPLICIT_1;
|
|
quotient = 0;
|
|
/* ??? Does divide one bit at a time. Optimize. */
|
|
while (bit)
|
|
{
|
|
if (numerator >= denominator)
|
|
{
|
|
quotient |= bit;
|
|
numerator -= denominator;
|
|
}
|
|
bit >>= 1;
|
|
numerator *= 2;
|
|
}
|
|
|
|
if ((quotient & GARDMASK) == GARDMSB)
|
|
{
|
|
if (quotient & (1 << NGARDS))
|
|
{
|
|
/* half way, so round to even */
|
|
quotient += GARDROUND + 1;
|
|
}
|
|
else if (numerator)
|
|
{
|
|
/* but we really weren't half way, more bits exist */
|
|
quotient += GARDROUND + 1;
|
|
}
|
|
}
|
|
|
|
a->fraction.ll = quotient;
|
|
return (a);
|
|
}
|
|
}
|
|
|
|
FLO_type
|
|
divide (FLO_type arg_a, FLO_type arg_b)
|
|
{
|
|
fp_number_type a;
|
|
fp_number_type b;
|
|
fp_number_type *res;
|
|
FLO_union_type au, bu;
|
|
|
|
au.value = arg_a;
|
|
bu.value = arg_b;
|
|
|
|
unpack_d (&au, &a);
|
|
unpack_d (&bu, &b);
|
|
|
|
res = _fpdiv_parts (&a, &b);
|
|
|
|
return pack_d (res);
|
|
}
|
|
#endif /* L_div_sf || L_div_df */
|
|
|
|
#if defined(L_fpcmp_parts_sf) || defined(L_fpcmp_parts_df)
|
|
/* according to the demo, fpcmp returns a comparison with 0... thus
|
|
a<b -> -1
|
|
a==b -> 0
|
|
a>b -> +1
|
|
*/
|
|
|
|
int
|
|
__fpcmp_parts (fp_number_type * a, fp_number_type * b)
|
|
{
|
|
#if 0
|
|
/* either nan -> unordered. Must be checked outside of this routine. */
|
|
if (isnan (a) && isnan (b))
|
|
{
|
|
return 1; /* still unordered! */
|
|
}
|
|
#endif
|
|
|
|
if (isnan (a) || isnan (b))
|
|
{
|
|
return 1; /* how to indicate unordered compare? */
|
|
}
|
|
if (isinf (a) && isinf (b))
|
|
{
|
|
/* +inf > -inf, but +inf != +inf */
|
|
/* b \a| +inf(0)| -inf(1)
|
|
______\+--------+--------
|
|
+inf(0)| a==b(0)| a<b(-1)
|
|
-------+--------+--------
|
|
-inf(1)| a>b(1) | a==b(0)
|
|
-------+--------+--------
|
|
So since unordered must be non zero, just line up the columns...
|
|
*/
|
|
return b->sign - a->sign;
|
|
}
|
|
/* but not both... */
|
|
if (isinf (a))
|
|
{
|
|
return a->sign ? -1 : 1;
|
|
}
|
|
if (isinf (b))
|
|
{
|
|
return b->sign ? 1 : -1;
|
|
}
|
|
if (iszero (a) && iszero (b))
|
|
{
|
|
return 0;
|
|
}
|
|
if (iszero (a))
|
|
{
|
|
return b->sign ? 1 : -1;
|
|
}
|
|
if (iszero (b))
|
|
{
|
|
return a->sign ? -1 : 1;
|
|
}
|
|
/* now both are "normal". */
|
|
if (a->sign != b->sign)
|
|
{
|
|
/* opposite signs */
|
|
return a->sign ? -1 : 1;
|
|
}
|
|
/* same sign; exponents? */
|
|
if (a->normal_exp > b->normal_exp)
|
|
{
|
|
return a->sign ? -1 : 1;
|
|
}
|
|
if (a->normal_exp < b->normal_exp)
|
|
{
|
|
return a->sign ? 1 : -1;
|
|
}
|
|
/* same exponents; check size. */
|
|
if (a->fraction.ll > b->fraction.ll)
|
|
{
|
|
return a->sign ? -1 : 1;
|
|
}
|
|
if (a->fraction.ll < b->fraction.ll)
|
|
{
|
|
return a->sign ? 1 : -1;
|
|
}
|
|
/* after all that, they're equal. */
|
|
return 0;
|
|
}
|
|
#endif
|
|
|
|
#if defined(L_compare_sf) || defined(L_compare_df)
|
|
CMPtype
|
|
compare (FLO_type arg_a, FLO_type arg_b)
|
|
{
|
|
fp_number_type a;
|
|
fp_number_type b;
|
|
FLO_union_type au, bu;
|
|
|
|
au.value = arg_a;
|
|
bu.value = arg_b;
|
|
|
|
unpack_d (&au, &a);
|
|
unpack_d (&bu, &b);
|
|
|
|
return __fpcmp_parts (&a, &b);
|
|
}
|
|
#endif /* L_compare_sf || L_compare_df */
|
|
|
|
#ifndef US_SOFTWARE_GOFAST
|
|
|
|
/* These should be optimized for their specific tasks someday. */
|
|
|
|
#if defined(L_eq_sf) || defined(L_eq_df)
|
|
CMPtype
|
|
_eq_f2 (FLO_type arg_a, FLO_type arg_b)
|
|
{
|
|
fp_number_type a;
|
|
fp_number_type b;
|
|
FLO_union_type au, bu;
|
|
|
|
au.value = arg_a;
|
|
bu.value = arg_b;
|
|
|
|
unpack_d (&au, &a);
|
|
unpack_d (&bu, &b);
|
|
|
|
if (isnan (&a) || isnan (&b))
|
|
return 1; /* false, truth == 0 */
|
|
|
|
return __fpcmp_parts (&a, &b) ;
|
|
}
|
|
#endif /* L_eq_sf || L_eq_df */
|
|
|
|
#if defined(L_ne_sf) || defined(L_ne_df)
|
|
CMPtype
|
|
_ne_f2 (FLO_type arg_a, FLO_type arg_b)
|
|
{
|
|
fp_number_type a;
|
|
fp_number_type b;
|
|
FLO_union_type au, bu;
|
|
|
|
au.value = arg_a;
|
|
bu.value = arg_b;
|
|
|
|
unpack_d (&au, &a);
|
|
unpack_d (&bu, &b);
|
|
|
|
if (isnan (&a) || isnan (&b))
|
|
return 1; /* true, truth != 0 */
|
|
|
|
return __fpcmp_parts (&a, &b) ;
|
|
}
|
|
#endif /* L_ne_sf || L_ne_df */
|
|
|
|
#if defined(L_gt_sf) || defined(L_gt_df)
|
|
CMPtype
|
|
_gt_f2 (FLO_type arg_a, FLO_type arg_b)
|
|
{
|
|
fp_number_type a;
|
|
fp_number_type b;
|
|
FLO_union_type au, bu;
|
|
|
|
au.value = arg_a;
|
|
bu.value = arg_b;
|
|
|
|
unpack_d (&au, &a);
|
|
unpack_d (&bu, &b);
|
|
|
|
if (isnan (&a) || isnan (&b))
|
|
return -1; /* false, truth > 0 */
|
|
|
|
return __fpcmp_parts (&a, &b);
|
|
}
|
|
#endif /* L_gt_sf || L_gt_df */
|
|
|
|
#if defined(L_ge_sf) || defined(L_ge_df)
|
|
CMPtype
|
|
_ge_f2 (FLO_type arg_a, FLO_type arg_b)
|
|
{
|
|
fp_number_type a;
|
|
fp_number_type b;
|
|
FLO_union_type au, bu;
|
|
|
|
au.value = arg_a;
|
|
bu.value = arg_b;
|
|
|
|
unpack_d (&au, &a);
|
|
unpack_d (&bu, &b);
|
|
|
|
if (isnan (&a) || isnan (&b))
|
|
return -1; /* false, truth >= 0 */
|
|
return __fpcmp_parts (&a, &b) ;
|
|
}
|
|
#endif /* L_ge_sf || L_ge_df */
|
|
|
|
#if defined(L_lt_sf) || defined(L_lt_df)
|
|
CMPtype
|
|
_lt_f2 (FLO_type arg_a, FLO_type arg_b)
|
|
{
|
|
fp_number_type a;
|
|
fp_number_type b;
|
|
FLO_union_type au, bu;
|
|
|
|
au.value = arg_a;
|
|
bu.value = arg_b;
|
|
|
|
unpack_d (&au, &a);
|
|
unpack_d (&bu, &b);
|
|
|
|
if (isnan (&a) || isnan (&b))
|
|
return 1; /* false, truth < 0 */
|
|
|
|
return __fpcmp_parts (&a, &b);
|
|
}
|
|
#endif /* L_lt_sf || L_lt_df */
|
|
|
|
#if defined(L_le_sf) || defined(L_le_df)
|
|
CMPtype
|
|
_le_f2 (FLO_type arg_a, FLO_type arg_b)
|
|
{
|
|
fp_number_type a;
|
|
fp_number_type b;
|
|
FLO_union_type au, bu;
|
|
|
|
au.value = arg_a;
|
|
bu.value = arg_b;
|
|
|
|
unpack_d (&au, &a);
|
|
unpack_d (&bu, &b);
|
|
|
|
if (isnan (&a) || isnan (&b))
|
|
return 1; /* false, truth <= 0 */
|
|
|
|
return __fpcmp_parts (&a, &b) ;
|
|
}
|
|
#endif /* L_le_sf || L_le_df */
|
|
|
|
#if defined(L_unord_sf) || defined(L_unord_df)
|
|
CMPtype
|
|
_unord_f2 (FLO_type arg_a, FLO_type arg_b)
|
|
{
|
|
fp_number_type a;
|
|
fp_number_type b;
|
|
FLO_union_type au, bu;
|
|
|
|
au.value = arg_a;
|
|
bu.value = arg_b;
|
|
|
|
unpack_d (&au, &a);
|
|
unpack_d (&bu, &b);
|
|
|
|
return (isnan (&a) || isnan (&b));
|
|
}
|
|
#endif /* L_unord_sf || L_unord_df */
|
|
|
|
#endif /* ! US_SOFTWARE_GOFAST */
|
|
|
|
#if defined(L_si_to_sf) || defined(L_si_to_df)
|
|
FLO_type
|
|
si_to_float (SItype arg_a)
|
|
{
|
|
fp_number_type in;
|
|
|
|
in.class = CLASS_NUMBER;
|
|
in.sign = arg_a < 0;
|
|
if (!arg_a)
|
|
{
|
|
in.class = CLASS_ZERO;
|
|
}
|
|
else
|
|
{
|
|
in.normal_exp = FRACBITS + NGARDS;
|
|
if (in.sign)
|
|
{
|
|
/* Special case for minint, since there is no +ve integer
|
|
representation for it */
|
|
if (arg_a == (- MAX_SI_INT - 1))
|
|
{
|
|
return (FLO_type)(- MAX_SI_INT - 1);
|
|
}
|
|
in.fraction.ll = (-arg_a);
|
|
}
|
|
else
|
|
in.fraction.ll = arg_a;
|
|
|
|
while (in.fraction.ll < (1LL << (FRACBITS + NGARDS)))
|
|
{
|
|
in.fraction.ll <<= 1;
|
|
in.normal_exp -= 1;
|
|
}
|
|
}
|
|
return pack_d (&in);
|
|
}
|
|
#endif /* L_si_to_sf || L_si_to_df */
|
|
|
|
#if defined(L_usi_to_sf) || defined(L_usi_to_df)
|
|
FLO_type
|
|
usi_to_float (USItype arg_a)
|
|
{
|
|
fp_number_type in;
|
|
|
|
in.sign = 0;
|
|
if (!arg_a)
|
|
{
|
|
in.class = CLASS_ZERO;
|
|
}
|
|
else
|
|
{
|
|
in.class = CLASS_NUMBER;
|
|
in.normal_exp = FRACBITS + NGARDS;
|
|
in.fraction.ll = arg_a;
|
|
|
|
while (in.fraction.ll > (1LL << (FRACBITS + NGARDS)))
|
|
{
|
|
in.fraction.ll >>= 1;
|
|
in.normal_exp += 1;
|
|
}
|
|
while (in.fraction.ll < (1LL << (FRACBITS + NGARDS)))
|
|
{
|
|
in.fraction.ll <<= 1;
|
|
in.normal_exp -= 1;
|
|
}
|
|
}
|
|
return pack_d (&in);
|
|
}
|
|
#endif
|
|
|
|
#if defined(L_sf_to_si) || defined(L_df_to_si)
|
|
SItype
|
|
float_to_si (FLO_type arg_a)
|
|
{
|
|
fp_number_type a;
|
|
SItype tmp;
|
|
FLO_union_type au;
|
|
|
|
au.value = arg_a;
|
|
unpack_d (&au, &a);
|
|
|
|
if (iszero (&a))
|
|
return 0;
|
|
if (isnan (&a))
|
|
return 0;
|
|
/* get reasonable MAX_SI_INT... */
|
|
if (isinf (&a))
|
|
return a.sign ? (-MAX_SI_INT)-1 : MAX_SI_INT;
|
|
/* it is a number, but a small one */
|
|
if (a.normal_exp < 0)
|
|
return 0;
|
|
if (a.normal_exp > BITS_PER_SI - 2)
|
|
return a.sign ? (-MAX_SI_INT)-1 : MAX_SI_INT;
|
|
tmp = a.fraction.ll >> ((FRACBITS + NGARDS) - a.normal_exp);
|
|
return a.sign ? (-tmp) : (tmp);
|
|
}
|
|
#endif /* L_sf_to_si || L_df_to_si */
|
|
|
|
#if defined(L_sf_to_usi) || defined(L_df_to_usi)
|
|
#ifdef US_SOFTWARE_GOFAST
|
|
/* While libgcc2.c defines its own __fixunssfsi and __fixunsdfsi routines,
|
|
we also define them for GOFAST because the ones in libgcc2.c have the
|
|
wrong names and I'd rather define these here and keep GOFAST CYG-LOC's
|
|
out of libgcc2.c. We can't define these here if not GOFAST because then
|
|
there'd be duplicate copies. */
|
|
|
|
USItype
|
|
float_to_usi (FLO_type arg_a)
|
|
{
|
|
fp_number_type a;
|
|
FLO_union_type au;
|
|
|
|
au.value = arg_a;
|
|
unpack_d (&au, &a);
|
|
|
|
if (iszero (&a))
|
|
return 0;
|
|
if (isnan (&a))
|
|
return 0;
|
|
/* it is a negative number */
|
|
if (a.sign)
|
|
return 0;
|
|
/* get reasonable MAX_USI_INT... */
|
|
if (isinf (&a))
|
|
return MAX_USI_INT;
|
|
/* it is a number, but a small one */
|
|
if (a.normal_exp < 0)
|
|
return 0;
|
|
if (a.normal_exp > BITS_PER_SI - 1)
|
|
return MAX_USI_INT;
|
|
else if (a.normal_exp > (FRACBITS + NGARDS))
|
|
return a.fraction.ll << (a.normal_exp - (FRACBITS + NGARDS));
|
|
else
|
|
return a.fraction.ll >> ((FRACBITS + NGARDS) - a.normal_exp);
|
|
}
|
|
#endif /* US_SOFTWARE_GOFAST */
|
|
#endif /* L_sf_to_usi || L_df_to_usi */
|
|
|
|
#if defined(L_negate_sf) || defined(L_negate_df)
|
|
FLO_type
|
|
negate (FLO_type arg_a)
|
|
{
|
|
fp_number_type a;
|
|
FLO_union_type au;
|
|
|
|
au.value = arg_a;
|
|
unpack_d (&au, &a);
|
|
|
|
flip_sign (&a);
|
|
return pack_d (&a);
|
|
}
|
|
#endif /* L_negate_sf || L_negate_df */
|
|
|
|
#ifdef FLOAT
|
|
|
|
#if defined(L_make_sf)
|
|
SFtype
|
|
__make_fp(fp_class_type class,
|
|
unsigned int sign,
|
|
int exp,
|
|
USItype frac)
|
|
{
|
|
fp_number_type in;
|
|
|
|
in.class = class;
|
|
in.sign = sign;
|
|
in.normal_exp = exp;
|
|
in.fraction.ll = frac;
|
|
return pack_d (&in);
|
|
}
|
|
#endif /* L_make_sf */
|
|
|
|
#ifndef FLOAT_ONLY
|
|
|
|
/* This enables one to build an fp library that supports float but not double.
|
|
Otherwise, we would get an undefined reference to __make_dp.
|
|
This is needed for some 8-bit ports that can't handle well values that
|
|
are 8-bytes in size, so we just don't support double for them at all. */
|
|
|
|
#if defined(L_sf_to_df)
|
|
DFtype
|
|
sf_to_df (SFtype arg_a)
|
|
{
|
|
fp_number_type in;
|
|
FLO_union_type au;
|
|
|
|
au.value = arg_a;
|
|
unpack_d (&au, &in);
|
|
|
|
return __make_dp (in.class, in.sign, in.normal_exp,
|
|
((UDItype) in.fraction.ll) << F_D_BITOFF);
|
|
}
|
|
#endif /* L_sf_to_df */
|
|
|
|
#endif /* ! FLOAT_ONLY */
|
|
#endif /* FLOAT */
|
|
|
|
#ifndef FLOAT
|
|
|
|
extern SFtype __make_fp (fp_class_type, unsigned int, int, USItype);
|
|
|
|
#if defined(L_make_df)
|
|
DFtype
|
|
__make_dp (fp_class_type class, unsigned int sign, int exp, UDItype frac)
|
|
{
|
|
fp_number_type in;
|
|
|
|
in.class = class;
|
|
in.sign = sign;
|
|
in.normal_exp = exp;
|
|
in.fraction.ll = frac;
|
|
return pack_d (&in);
|
|
}
|
|
#endif /* L_make_df */
|
|
|
|
#if defined(L_df_to_sf)
|
|
SFtype
|
|
df_to_sf (DFtype arg_a)
|
|
{
|
|
fp_number_type in;
|
|
USItype sffrac;
|
|
FLO_union_type au;
|
|
|
|
au.value = arg_a;
|
|
unpack_d (&au, &in);
|
|
|
|
sffrac = in.fraction.ll >> F_D_BITOFF;
|
|
|
|
/* We set the lowest guard bit in SFFRAC if we discarded any non
|
|
zero bits. */
|
|
if ((in.fraction.ll & (((USItype) 1 << F_D_BITOFF) - 1)) != 0)
|
|
sffrac |= 1;
|
|
|
|
return __make_fp (in.class, in.sign, in.normal_exp, sffrac);
|
|
}
|
|
#endif /* L_df_to_sf */
|
|
|
|
#endif /* ! FLOAT */
|
|
#endif /* !EXTENDED_FLOAT_STUBS */
|