mirror of
https://github.com/ZDoom/raze-gles.git
synced 2024-12-28 12:30:46 +00:00
262 lines
5.2 KiB
C
262 lines
5.2 KiB
C
|
/* isnan()
|
|||
|
|
* signbit()
|
|||
|
|
* isfinite()
|
|||
|
|
*
|
|||
|
|
* Floating point numeric utilities
|
|||
|
|
*
|
|||
|
|
*
|
|||
|
|
*
|
|||
|
|
* SYNOPSIS:
|
|||
|
|
*
|
|||
|
|
* double ceil(), floor(), frexp(), ldexp();
|
|||
|
|
* int signbit(), isnan(), isfinite();
|
|||
|
|
* double x, y;
|
|||
|
|
* int expnt, n;
|
|||
|
|
*
|
|||
|
|
* y = floor(x);
|
|||
|
|
* y = ceil(x);
|
|||
|
|
* y = frexp( x, &expnt );
|
|||
|
|
* y = ldexp( x, n );
|
|||
|
|
* n = signbit(x);
|
|||
|
|
* n = isnan(x);
|
|||
|
|
* n = isfinite(x);
|
|||
|
|
*
|
|||
|
|
*
|
|||
|
|
*
|
|||
|
|
* DESCRIPTION:
|
|||
|
|
*
|
|||
|
|
* All four routines return a double precision floating point
|
|||
|
|
* result.
|
|||
|
|
*
|
|||
|
|
* floor() returns the largest integer less than or equal to x.
|
|||
|
|
* It truncates toward minus infinity.
|
|||
|
|
*
|
|||
|
|
* ceil() returns the smallest integer greater than or equal
|
|||
|
|
* to x. It truncates toward plus infinity.
|
|||
|
|
*
|
|||
|
|
* frexp() extracts the exponent from x. It returns an integer
|
|||
|
|
* power of two to expnt and the significand between 0.5 and 1
|
|||
|
|
* to y. Thus x = y * 2**expn.
|
|||
|
|
*
|
|||
|
|
* ldexp() multiplies x by 2**n.
|
|||
|
|
*
|
|||
|
|
* signbit(x) returns 1 if the sign bit of x is 1, else 0.
|
|||
|
|
*
|
|||
|
|
* These functions are part of the standard C run time library
|
|||
|
|
* for many but not all C compilers. The ones supplied are
|
|||
|
|
* written in C for either DEC or IEEE arithmetic. They should
|
|||
|
|
* be used only if your compiler library does not already have
|
|||
|
|
* them.
|
|||
|
|
*
|
|||
|
|
* The IEEE versions assume that denormal numbers are implemented
|
|||
|
|
* in the arithmetic. Some modifications will be required if
|
|||
|
|
* the arithmetic has abrupt rather than gradual underflow.
|
|||
|
|
*/
|
|||
|
|
|
|||
|
|
|
|||
|
|
/*
|
|||
|
|
Cephes Math Library Release 2.3: March, 1995
|
|||
|
|
Copyright 1984, 1995 by Stephen L. Moshier
|
|||
|
|
|
|||
|
|
Redistribution and use in source and binary forms, with or without
|
|||
|
|
modification, are permitted provided that the following conditions are met:
|
|||
|
|
|
|||
|
|
1. Redistributions of source code must retain the above copyright notice,
|
|||
|
|
this list of conditions and the following disclaimer.
|
|||
|
|
2. Redistributions in binary form must reproduce the above copyright
|
|||
|
|
notice, this list of conditions and the following disclaimer in the
|
|||
|
|
documentation and/or other materials provided with the distribution.
|
|||
|
|
3. Neither the name of the <ORGANIZATION> nor the names of its
|
|||
|
|
contributors may be used to endorse or promote products derived from
|
|||
|
|
this software without specific prior written permission.
|
|||
|
|
|
|||
|
|
THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
|
|||
|
|
AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
|
|||
|
|
IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
|
|||
|
|
ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
|
|||
|
|
LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
|
|||
|
|
CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
|
|||
|
|
SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
|
|||
|
|
INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
|
|||
|
|
CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
|
|||
|
|
ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
|
|||
|
|
POSSIBILITY OF SUCH DAMAGE.
|
|||
|
|
*/
|
|||
|
|
|
|||
|
|
|
|||
|
|
#include "mconf.h"
|
|||
|
|
|
|||
|
|
#ifdef UNK
|
|||
|
|
/* ceil(), floor(), frexp(), ldexp() may need to be rewritten. */
|
|||
|
|
#undef UNK
|
|||
|
|
#if BIGENDIAN
|
|||
|
|
#define MIEEE 1
|
|||
|
|
#else
|
|||
|
|
#define IBMPC 1
|
|||
|
|
#endif
|
|||
|
|
#endif
|
|||
|
|
|
|||
|
|
|
|||
|
|
/* Return 1 if the sign bit of x is 1, else 0. */
|
|||
|
|
|
|||
|
|
int signbit(x)
|
|||
|
|
double x;
|
|||
|
|
{
|
|||
|
|
union
|
|||
|
|
{
|
|||
|
|
double d;
|
|||
|
|
short s[4];
|
|||
|
|
int i[2];
|
|||
|
|
} u;
|
|||
|
|
|
|||
|
|
u.d = x;
|
|||
|
|
|
|||
|
|
if( sizeof(int) == 4 )
|
|||
|
|
{
|
|||
|
|
#ifdef IBMPC
|
|||
|
|
return( u.i[1] < 0 );
|
|||
|
|
#endif
|
|||
|
|
#ifdef DEC
|
|||
|
|
return( u.s[3] < 0 );
|
|||
|
|
#endif
|
|||
|
|
#ifdef MIEEE
|
|||
|
|
return( u.i[0] < 0 );
|
|||
|
|
#endif
|
|||
|
|
}
|
|||
|
|
else
|
|||
|
|
{
|
|||
|
|
#ifdef IBMPC
|
|||
|
|
return( u.s[3] < 0 );
|
|||
|
|
#endif
|
|||
|
|
#ifdef DEC
|
|||
|
|
return( u.s[3] < 0 );
|
|||
|
|
#endif
|
|||
|
|
#ifdef MIEEE
|
|||
|
|
return( u.s[0] < 0 );
|
|||
|
|
#endif
|
|||
|
|
}
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
|
|||
|
|
/* Return 1 if x is a number that is Not a Number, else return 0. */
|
|||
|
|
|
|||
|
|
int isnan(x)
|
|||
|
|
double x;
|
|||
|
|
{
|
|||
|
|
#ifdef NANS
|
|||
|
|
union
|
|||
|
|
{
|
|||
|
|
double d;
|
|||
|
|
unsigned short s[4];
|
|||
|
|
unsigned int i[2];
|
|||
|
|
} u;
|
|||
|
|
|
|||
|
|
u.d = x;
|
|||
|
|
|
|||
|
|
if( sizeof(int) == 4 )
|
|||
|
|
{
|
|||
|
|
#ifdef IBMPC
|
|||
|
|
if( ((u.i[1] & 0x7ff00000) == 0x7ff00000)
|
|||
|
|
&& (((u.i[1] & 0x000fffff) != 0) || (u.i[0] != 0)))
|
|||
|
|
return 1;
|
|||
|
|
#endif
|
|||
|
|
#ifdef DEC
|
|||
|
|
if( (u.s[1] & 0x7fff) == 0)
|
|||
|
|
{
|
|||
|
|
if( (u.s[2] | u.s[1] | u.s[0]) != 0 )
|
|||
|
|
return(1);
|
|||
|
|
}
|
|||
|
|
#endif
|
|||
|
|
#ifdef MIEEE
|
|||
|
|
if( ((u.i[0] & 0x7ff00000) == 0x7ff00000)
|
|||
|
|
&& (((u.i[0] & 0x000fffff) != 0) || (u.i[1] != 0)))
|
|||
|
|
return 1;
|
|||
|
|
#endif
|
|||
|
|
return(0);
|
|||
|
|
}
|
|||
|
|
else
|
|||
|
|
{ /* size int not 4 */
|
|||
|
|
#ifdef IBMPC
|
|||
|
|
if( (u.s[3] & 0x7ff0) == 0x7ff0)
|
|||
|
|
{
|
|||
|
|
if( ((u.s[3] & 0x000f) | u.s[2] | u.s[1] | u.s[0]) != 0 )
|
|||
|
|
return(1);
|
|||
|
|
}
|
|||
|
|
#endif
|
|||
|
|
#ifdef DEC
|
|||
|
|
if( (u.s[3] & 0x7fff) == 0)
|
|||
|
|
{
|
|||
|
|
if( (u.s[2] | u.s[1] | u.s[0]) != 0 )
|
|||
|
|
return(1);
|
|||
|
|
}
|
|||
|
|
#endif
|
|||
|
|
#ifdef MIEEE
|
|||
|
|
if( (u.s[0] & 0x7ff0) == 0x7ff0)
|
|||
|
|
{
|
|||
|
|
if( ((u.s[0] & 0x000f) | u.s[1] | u.s[2] | u.s[3]) != 0 )
|
|||
|
|
return(1);
|
|||
|
|
}
|
|||
|
|
#endif
|
|||
|
|
return(0);
|
|||
|
|
} /* size int not 4 */
|
|||
|
|
|
|||
|
|
#else
|
|||
|
|
/* No NANS. */
|
|||
|
|
return(0);
|
|||
|
|
#endif
|
|||
|
|
}
|
|||
|
|
|
|||
|
|
|
|||
|
|
/* Return 1 if x is not infinite and is not a NaN. */
|
|||
|
|
|
|||
|
|
int isfinite(x)
|
|||
|
|
double x;
|
|||
|
|
{
|
|||
|
|
#ifdef INFINITIES
|
|||
|
|
union
|
|||
|
|
{
|
|||
|
|
double d;
|
|||
|
|
unsigned short s[4];
|
|||
|
|
unsigned int i[2];
|
|||
|
|
} u;
|
|||
|
|
|
|||
|
|
u.d = x;
|
|||
|
|
|
|||
|
|
if( sizeof(int) == 4 )
|
|||
|
|
{
|
|||
|
|
#ifdef IBMPC
|
|||
|
|
if( (u.i[1] & 0x7ff00000) != 0x7ff00000)
|
|||
|
|
return 1;
|
|||
|
|
#endif
|
|||
|
|
#ifdef DEC
|
|||
|
|
if( (u.s[3] & 0x7fff) != 0)
|
|||
|
|
return 1;
|
|||
|
|
#endif
|
|||
|
|
#ifdef MIEEE
|
|||
|
|
if( (u.i[0] & 0x7ff00000) != 0x7ff00000)
|
|||
|
|
return 1;
|
|||
|
|
#endif
|
|||
|
|
return(0);
|
|||
|
|
}
|
|||
|
|
else
|
|||
|
|
{
|
|||
|
|
#ifdef IBMPC
|
|||
|
|
if( (u.s[3] & 0x7ff0) != 0x7ff0)
|
|||
|
|
return 1;
|
|||
|
|
#endif
|
|||
|
|
#ifdef DEC
|
|||
|
|
if( (u.s[3] & 0x7fff) != 0)
|
|||
|
|
return 1;
|
|||
|
|
#endif
|
|||
|
|
#ifdef MIEEE
|
|||
|
|
if( (u.s[0] & 0x7ff0) != 0x7ff0)
|
|||
|
|
return 1;
|
|||
|
|
#endif
|
|||
|
|
return(0);
|
|||
|
|
}
|
|||
|
|
#else
|
|||
|
|
/* No INFINITY. */
|
|||
|
|
return(1);
|
|||
|
|
#endif
|
|||
|
|
}
|