cave-story-solaris/external/SDL2/src/libm/s_floor.c
Clownacy ac465d29b4 Mean CMake dependency overhaul
I'm taking a page from Dolphin's book, and including copies of each
dependency's source code. This combines the ease of use of including
pre-built libraries instead of needing to navigate a package manager
 - as is (or was) the case for MSVC - with the portability of using
packages. Granted, this method's more of a jack of all trades,
master of none, since it's *less* user-friendly than prebuilt
packages (compilation times), and you don't get the per-distro
compatibility fixes you'd get from a package manager.

You can still use system libs if you want. In fact, it's still the
default behaviour: compiling the libs manually is just a fallback.
I'll add an option to force-enable this soon, however, since it's a
nicer way to produce static MSYS2 builds than the hackish nightmare
that I was using before. Not to mention, having my own copy of the
sources means I can provide my own fixes and tweaks your package
manager may not. For example, I can combine MSYS2's FreeType
subpixel rendering with vcpkg's fix for SDL2 exporting its symbols
in static builds.
2019-04-26 01:52:02 +01:00

71 lines
1.7 KiB
C

/*
* ====================================================
* Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
*
* Developed at SunPro, a Sun Microsystems, Inc. business.
* Permission to use, copy, modify, and distribute this
* software is freely granted, provided that this notice
* is preserved.
* ====================================================
*/
/*
* floor(x)
* Return x rounded toward -inf to integral value
* Method:
* Bit twiddling.
* Exception:
* Inexact flag raised if x not equal to floor(x).
*/
/*#include <features.h>*/
/* Prevent math.h from defining a colliding inline */
#undef __USE_EXTERN_INLINES
#include "math_libm.h"
#include "math_private.h"
static const double huge = 1.0e300;
double floor(double x)
{
int32_t i0,i1,j0;
u_int32_t i,j;
EXTRACT_WORDS(i0,i1,x);
j0 = ((i0>>20)&0x7ff)-0x3ff;
if(j0<20) {
if(j0<0) { /* raise inexact if x != 0 */
if(huge+x>0.0) {/* return 0*sign(x) if |x|<1 */
if(i0>=0) {i0=i1=0;}
else if(((i0&0x7fffffff)|i1)!=0)
{ i0=0xbff00000;i1=0;}
}
} else {
i = (0x000fffff)>>j0;
if(((i0&i)|i1)==0) return x; /* x is integral */
if(huge+x>0.0) { /* raise inexact flag */
if(i0<0) i0 += (0x00100000)>>j0;
i0 &= (~i); i1=0;
}
}
} else if (j0>51) {
if(j0==0x400) return x+x; /* inf or NaN */
else return x; /* x is integral */
} else {
i = ((u_int32_t)(0xffffffff))>>(j0-20);
if((i1&i)==0) return x; /* x is integral */
if(huge+x>0.0) { /* raise inexact flag */
if(i0<0) {
if(j0==20) i0+=1;
else {
j = i1+(1<<(52-j0));
if(j<(u_int32_t)i1) i0 +=1 ; /* got a carry */
i1=j;
}
}
i1 &= (~i);
}
}
INSERT_WORDS(x,i0,i1);
return x;
}
libm_hidden_def(floor)