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+/*
+** Copyright (C) 2001-2004 Erik de Castro Lopo <erikd@mega-nerd.com>
+**
+** This program is free software; you can redistribute it and/or modify
+** it under the terms of the GNU Lesser General Public License as published by
+** the Free Software Foundation; either version 2.1 of the License, or
+** (at your option) any later version.
+**
+** This program is distributed in the hope that it will be useful,
+** but WITHOUT ANY WARRANTY; without even the implied warranty of
+** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+** GNU Lesser General Public License for more details.
+**
+** You should have received a copy of the GNU Lesser General Public License
+** along with this program; if not, write to the Free Software
+** Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+*/
+
+/* Version 1.4 */
+
+#ifndef FLOAT_CAST_HEADER
+#define FLOAT_CAST_HEADER
+
+/*============================================================================
+** 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 "sfconfig.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 sfconfig.h file.
+*/
+
+#define HAVE_LRINT_REPLACEMENT 0
+
+#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 (__CYGWIN__))
+
+ #include <math.h>
+
+ #undef HAVE_LRINT_REPLACEMENT
+ #define HAVE_LRINT_REPLACEMENT 1
+
+ #undef lrint
+ #undef lrintf
+
+ #define lrint double2int
+ #define lrintf float2int
+
+ /*
+ ** The native CYGWIN lrint and lrintf functions are buggy:
+ ** http://sourceware.org/ml/cygwin/2005-06/msg00153.html
+ ** http://sourceware.org/ml/cygwin/2005-09/msg00047.html
+ ** and slow.
+ ** These functions (pulled from the Public Domain MinGW math.h header)
+ ** replace the native versions.
+ */
+
+ static inline long double2int (double in)
+ { long retval ;
+
+ __asm__ __volatile__
+ ( "fistpl %0"
+ : "=m" (retval)
+ : "t" (in)
+ : "st"
+ ) ;
+
+ return retval ;
+ } /* double2int */
+
+ static inline long float2int (float in)
+ { long retval ;
+
+ __asm__ __volatile__
+ ( "fistpl %0"
+ : "=m" (retval)
+ : "t" (in)
+ : "st"
+ ) ;
+
+ return retval ;
+ } /* float2int */
+
+#elif (defined (WIN32) || defined (_WIN32))
+
+ #undef HAVE_LRINT_REPLACEMENT
+ #define HAVE_LRINT_REPLACEMENT 1
+
+ #include <math.h>
+
+ /*
+ ** Win32 doesn't seem to have these functions.
+ ** Therefore implement inline versions of these functions here.
+ */
+
+ __inline long int
+ lrint (double flt)
+ { int intgr ;
+
+ _asm
+ { fld flt
+ fistp intgr
+ } ;
+
+ return intgr ;
+ }
+
+ __inline long int
+ lrintf (float flt)
+ { int intgr ;
+
+ _asm
+ { fld flt
+ fistp intgr
+ } ;
+
+ return intgr ;
+ }
+
+#elif (defined (__MWERKS__) && defined (macintosh))
+
+ /* This MacOS 9 solution was provided by Stephane Letz */
+
+ #undef HAVE_LRINT_REPLACEMENT
+ #define HAVE_LRINT_REPLACEMENT 1
+ #include <math.h>
+
+ #undef lrint
+ #undef lrintf
+
+ #define lrint double2int
+ #define lrintf float2int
+
+ inline int
+ float2int (register float in)
+ { long res [2] ;
+
+ asm
+ { fctiw in, in
+ stfd in, res
+ }
+ return res [1] ;
+ } /* float2int */
+
+ inline int
+ double2int (register double in)
+ { long res [2] ;
+
+ asm
+ { fctiw in, in
+ stfd in, res
+ }
+ return res [1] ;
+ } /* double2int */
+
+#elif (defined (__MACH__) && defined (__APPLE__))
+
+ /* For Apple MacOSX. */
+
+ #undef HAVE_LRINT_REPLACEMENT
+ #define HAVE_LRINT_REPLACEMENT 1
+ #include <math.h>
+
+ #undef lrint
+ #undef lrintf
+
+ #define lrint double2int
+ #define lrintf float2int
+
+ inline static long
+ float2int (register float in)
+ { int res [2] ;
+
+ __asm__ __volatile__
+ ( "fctiw %1, %1\n\t"
+ "stfd %1, %0"
+ : "=m" (res) /* Output */
+ : "f" (in) /* Input */
+ : "memory"
+ ) ;
+
+ return res [1] ;
+ } /* lrintf */
+
+ inline static long
+ double2int (register double in)
+ { int res [2] ;
+
+ __asm__ __volatile__
+ ( "fctiw %1, %1\n\t"
+ "stfd %1, %0"
+ : "=m" (res) /* Output */
+ : "f" (in) /* Input */
+ : "memory"
+ ) ;
+
+ return res [1] ;
+ } /* lrint */
+
+#else
+ #ifndef __sgi
+ #warning "Don't have the functions lrint() and lrintf()."
+ #warning "Replacing these functions with a standard C cast."
+ #endif
+
+ #include <math.h>
+
+ #define lrint(dbl) ((long) (dbl))
+ #define lrintf(flt) ((long) (flt))
+
+#endif
+
+
+#endif /* FLOAT_CAST_HEADER */
+
+/*
+** Do not edit or modify anything in this comment block.
+** The arch-tag line is a file identity tag for the GNU Arch
+** revision control system.
+**
+** arch-tag: 42db1693-ff61-4051-bac1-e4d24c4e30b7
+*/