/*
** Copyright (C) 2001 Erik de Castro Lopo <erikd AT mega-nerd DOT com>
**
** Permission to use, copy, modify, distribute, and sell this file for any 
** purpose is hereby granted without fee, provided that the above copyright 
** and this permission notice appear in all copies.  No representations are
** made about the suitability of this software for any purpose.  It is 
** provided "as is" without express or implied warranty.
*/

/* Version 1.1 */


/*============================================================================ 
** On Intel Pentium processors (especially PIII and probably P4), converting
** from float to int is very slow. To meet the C specs, the code produced by 
** most C compilers targeting Pentium needs to change the FPU rounding mode 
** before the float to int conversion is performed. 
**
** Changing the FPU rounding mode causes the FPU pipeline to be flushed. It 
** is this flushing of the pipeline which is so slow.
**
** Fortunately the ISO C99 specifications define the functions lrint, lrintf,
** llrint and llrintf which fix this problem as a side effect. 
**
** On Unix-like systems, the configure process should have detected the 
** presence of these functions. If they weren't found we have to replace them 
** here with a standard C cast.
*/

/*	
** The C99 prototypes for lrint and lrintf are as follows:
**	
** long int lrintf (float x) ;
** long int lrint  (double x) ;
*/

//#include "config.h"

/* The presence of the required functions are detected during the configure
** process and the values HAVE_LRINT and HAVE_LRINTF are set accordingly in
** the config.h file.
*/

#ifndef __FLOAT_CAST_H__
#define __FLOAT_CAST_H__

#if (HAVE_LRINT && HAVE_LRINTF)

/* These defines enable functionality introduced with the 1999 ISO C
** standard. They must be defined before the inclusion of math.h to
** engage them. If optimisation is enabled, these functions will be 
** inlined. With optimisation switched off, you have to link in the
** maths library using -lm.
*/

#define	_ISOC9X_SOURCE	1
#define _ISOC99_SOURCE	1

#define	__USE_ISOC9X	1
#define	__USE_ISOC99	1

#include	<math.h>
	
#elif (defined (WIN32) || defined (_WIN32))

/* Win32 doesn't seem to have these functions. 
** Therefore implement inline versions of these functions here.
*/
	
__forceinline long int lrint (double flt) {
    long int intgr;
    __asm {
        fld flt
        fistp intgr
    }
    return intgr;
} 
	
__forceinline long int lrintf(float flt) {
    long int intgr;
    __asm {
        fld flt
        fistp intgr
    }
    return intgr;
}

__forceinline long int lrintl(long double flt) {
    long int intgr;
    __asm {
        fld flt
        fistp intgr
    }
    return intgr;
}

__forceinline long long int llrint(double flt) {
    long long int intgr;
    __asm {
        fld flt
        fistp intgr
    }
    return intgr;
}

__forceinline long long int llrintf(float flt) {
    long long int intgr;
    __asm {
        fld flt
        fistp intgr
    }
    return intgr;
}

__forceinline long long int llrintl(long double flt) {
    long long int intgr;
    __asm {
        fld flt
        fistp intgr
    }
    return intgr;
}

#endif

#endif /* __FLOAT_CAST_H__ */