float.h

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/*
 * float.h
 * This file has no copyright assigned and is placed in the Public Domain.
 * This file is a part of the mingw-runtime package.
 * No warranty is given; refer to the file DISCLAIMER within the package.
 *
 * Constants related to floating point arithmetic.
 *
 * Also included here are some non-ANSI bits for accessing the floating
 * point controller.
 *
 * NOTE: GCC provides float.h, but it doesn't include the non-standard
 *       stuff for accessing the fp controller. We include_next the
 *       GCC-supplied header and just define the MS-specific extensions
 *       here.
 *
 */

#ifndef _MINGW_FLOAT_H_
#define _MINGW_FLOAT_H_

#if defined(__GNUC__)
#include "mingw32/gcc_float.h"
#elif defined(_MSC_VER)
#include "msc/msc_float.h"
#else
#error
#endif

#include <crtdefs.h>

/*
 * Functions and definitions for controlling the FPU.
 */
#ifndef __STRICT_ANSI__

/* TODO: These constants are only valid for x86 machines */

/* Control word masks for unMask */
#define _MCW_EM     0x0008001F  /* Error masks */
#define _MCW_IC     0x00040000  /* Infinity */
#define _MCW_RC     0x00000300  /* Rounding */
#define _MCW_PC     0x00030000  /* Precision */
#define _MCW_DN     0x03000000  /* Denormal */

/* Control word values for unNew (use with related unMask above) */
#define _EM_INVALID 0x00000010
#define _EM_DENORMAL    0x00080000
#define _EM_ZERODIVIDE  0x00000008
#define _EM_OVERFLOW    0x00000004
#define _EM_UNDERFLOW   0x00000002
#define _EM_INEXACT 0x00000001
#define _IC_AFFINE  0x00040000
#define _IC_PROJECTIVE  0x00000000
#define _RC_CHOP    0x00000300
#define _RC_UP      0x00000200
#define _RC_DOWN    0x00000100
#define _RC_NEAR    0x00000000
#define _PC_24      0x00020000
#define _PC_53      0x00010000
#define _PC_64      0x00000000

/* These are also defined in Mingw math.h, needed to work around
   GCC build issues.  */
/* Return values for fpclass. */
#ifndef __MINGW_FPCLASS_DEFINED
#define __MINGW_FPCLASS_DEFINED 1
#define _FPCLASS_SNAN   0x0001  /* Signaling "Not a Number" */
#define _FPCLASS_QNAN   0x0002  /* Quiet "Not a Number" */
#define _FPCLASS_NINF   0x0004  /* Negative Infinity */
#define _FPCLASS_NN 0x0008  /* Negative Normal */
#define _FPCLASS_ND 0x0010  /* Negative Denormal */
#define _FPCLASS_NZ 0x0020  /* Negative Zero */
#define _FPCLASS_PZ 0x0040  /* Positive Zero */
#define _FPCLASS_PD 0x0080  /* Positive Denormal */
#define _FPCLASS_PN 0x0100  /* Positive Normal */
#define _FPCLASS_PINF   0x0200  /* Positive Infinity */
#endif /* __MINGW_FPCLASS_DEFINED */

/* invalid subconditions (_SW_INVALID also set) */
#define _SW_UNEMULATED      0x0040  /* unemulated instruction */
#define _SW_SQRTNEG     0x0080  /* square root of a neg number */
#define _SW_STACKOVERFLOW   0x0200  /* FP stack overflow */
#define _SW_STACKUNDERFLOW  0x0400  /* FP stack underflow */

/*  Floating point error signals and return codes */
#define _FPE_INVALID        0x81
#define _FPE_DENORMAL       0x82
#define _FPE_ZERODIVIDE     0x83
#define _FPE_OVERFLOW       0x84
#define _FPE_UNDERFLOW      0x85
#define _FPE_INEXACT        0x86
#define _FPE_UNEMULATED     0x87
#define _FPE_SQRTNEG        0x88
#define _FPE_STACKOVERFLOW  0x8a
#define _FPE_STACKUNDERFLOW 0x8b
#define _FPE_EXPLICITGEN    0x8c    /* raise( SIGFPE ); */

#ifndef RC_INVOKED

#ifdef  __cplusplus
extern "C" {
#endif

/* Set the FPU control word as cw = (cw & ~unMask) | (unNew & unMask),
 * i.e. change the bits in unMask to have the values they have in unNew,
 * leaving other bits unchanged. */

__MINGW_NOTHROW
_CRTIMP
unsigned int
__cdecl
_controlfp(
  _In_ unsigned int unNew,
  _In_ unsigned int unMask);

__MINGW_NOTHROW
_CRTIMP
unsigned int
__cdecl
_control87(
  _In_ unsigned int unNew,
  _In_ unsigned int unMask);

__MINGW_NOTHROW _CRTIMP unsigned int __cdecl _clearfp (void);   /* Clear the FPU status word */
__MINGW_NOTHROW _CRTIMP unsigned int __cdecl _statusfp (void);  /* Report the FPU status word */
#define     _clear87    _clearfp
#define     _status87   _statusfp


/*
   MSVCRT.dll _fpreset initializes the control register to 0x27f,
   the status register to zero and the tag word to 0FFFFh.
   This differs from asm instruction finit/fninit which set control
   word to 0x37f (64 bit mantissa precison rather than 53 bit).
   By default, the mingw version of _fpreset sets fp control as
   per fninit. To use the MSVCRT.dll _fpreset, include CRT_fp8.o when
   building your application.
*/
__MINGW_NOTHROW void __cdecl _fpreset (void);
__MINGW_NOTHROW void __cdecl fpreset (void);

/* Global 'variable' for the current floating point error code. */
__MINGW_NOTHROW _CRTIMP int * __cdecl __fpecode(void);
#define _fpecode    (*(__fpecode()))

/*
 * IEEE recommended functions.  MS puts them in float.h
 * but they really belong in math.h.
 */

_Check_return_
__MINGW_NOTHROW
_CRTIMP
double
__cdecl
_chgsign(
  _In_ double);

_Check_return_
__MINGW_NOTHROW
_CRTIMP
double
__cdecl
_copysign(
  _In_ double,
  _In_ double);

_Check_return_
__MINGW_NOTHROW
_CRTIMP
double
__cdecl
_logb(
  _In_ double);

_Check_return_
__MINGW_NOTHROW
_CRTIMP
double
__cdecl
_nextafter(
  _In_ double,
  _In_ double);

_Check_return_
__MINGW_NOTHROW
_CRTIMP
double
__cdecl
_scalb(
  _In_ double,
  _In_ long);

_Check_return_
__MINGW_NOTHROW
_CRTIMP
int
__cdecl
_finite(
  _In_ double);

_Check_return_
__MINGW_NOTHROW
_CRTIMP
int
__cdecl
_fpclass(
  _In_ double);

_Check_return_
__MINGW_NOTHROW
_CRTIMP
int
__cdecl
_isnan(
  _In_ double);

#ifdef __cplusplus
}
#endif

#endif  /* Not RC_INVOKED */

#endif  /* Not __STRICT_ANSI__ */

#endif /* _MINGW_FLOAT_H_ */