include/crt/float.h

   1 /*
   2  * float.h
   3  * This file has no copyright assigned and is placed in the Public Domain.
   4  * This file is a part of the mingw-runtime package.
   5  * No warranty is given; refer to the file DISCLAIMER within the package.
   6  *
   7  * Constants related to floating point arithmetic.
   8  *
   9  * Also included here are some non-ANSI bits for accessing the floating
  10  * point controller.
  11  *
  12  * NOTE: GCC provides float.h, but it doesn't include the non-standard
  13  *       stuff for accessing the fp controller. We include_next the
  14  *       GCC-supplied header and just define the MS-specific extensions
  15  *       here.
  16  *
  17  */
  18
  19 #if defined(__GNUC__)
  20 #include <gcc_float.h>
  21 #elif defined(_MSC_VER)
  22 #include <msc_float.h>
  23 #else
  24 #error
  25 #endif
  26
  27 #ifndef _MINGW_FLOAT_H_
  28 #define _MINGW_FLOAT_H_
  29
  30 #include <crtdefs.h>
  31
  32 /*
  33  * Functions and definitions for controlling the FPU.
  34  */
  35 #ifndef __STRICT_ANSI__
  36
  37 /* TODO: These constants are only valid for x86 machines */
  38
  39 /* Control word masks for unMask */
  40 #define _MCW_EM         0x0008001F      /* Error masks */
  41 #define _MCW_IC         0x00040000      /* Infinity */
  42 #define _MCW_RC         0x00000300      /* Rounding */
  43 #define _MCW_PC         0x00030000      /* Precision */
  44 #define _MCW_DN     0x03000000  /* Denormal */
  45
  46 /* Control word values for unNew (use with related unMask above) */
  47 #define _EM_INVALID     0x00000010
  48 #define _EM_DENORMAL    0x00080000
  49 #define _EM_ZERODIVIDE  0x00000008
  50 #define _EM_OVERFLOW    0x00000004
  51 #define _EM_UNDERFLOW   0x00000002
  52 #define _EM_INEXACT     0x00000001
  53 #define _IC_AFFINE      0x00040000
  54 #define _IC_PROJECTIVE  0x00000000
  55 #define _RC_CHOP        0x00000300
  56 #define _RC_UP          0x00000200
  57 #define _RC_DOWN        0x00000100
  58 #define _RC_NEAR        0x00000000
  59 #define _PC_24          0x00020000
  60 #define _PC_53          0x00010000
  61 #define _PC_64          0x00000000
  62
  63 /* These are also defined in Mingw math.h, needed to work around
  64    GCC build issues.  */
  65 /* Return values for fpclass. */
  66 #ifndef __MINGW_FPCLASS_DEFINED
  67 #define __MINGW_FPCLASS_DEFINED 1
  68 #define _FPCLASS_SNAN   0x0001  /* Signaling "Not a Number" */
  69 #define _FPCLASS_QNAN   0x0002  /* Quiet "Not a Number" */
  70 #define _FPCLASS_NINF   0x0004  /* Negative Infinity */
  71 #define _FPCLASS_NN     0x0008  /* Negative Normal */
  72 #define _FPCLASS_ND     0x0010  /* Negative Denormal */
  73 #define _FPCLASS_NZ     0x0020  /* Negative Zero */
  74 #define _FPCLASS_PZ     0x0040  /* Positive Zero */
  75 #define _FPCLASS_PD     0x0080  /* Positive Denormal */
  76 #define _FPCLASS_PN     0x0100  /* Positive Normal */
  77 #define _FPCLASS_PINF   0x0200  /* Positive Infinity */
  78 #endif /* __MINGW_FPCLASS_DEFINED */
  79
  80 /* invalid subconditions (_SW_INVALID also set) */
  81 #define _SW_UNEMULATED          0x0040  /* unemulated instruction */
  82 #define _SW_SQRTNEG             0x0080  /* square root of a neg number */
  83 #define _SW_STACKOVERFLOW       0x0200  /* FP stack overflow */
  84 #define _SW_STACKUNDERFLOW      0x0400  /* FP stack underflow */
  85
  86 /*  Floating point error signals and return codes */
  87 #define _FPE_INVALID            0x81
  88 #define _FPE_DENORMAL           0x82
  89 #define _FPE_ZERODIVIDE         0x83
  90 #define _FPE_OVERFLOW           0x84
  91 #define _FPE_UNDERFLOW          0x85
  92 #define _FPE_INEXACT            0x86
  93 #define _FPE_UNEMULATED         0x87
  94 #define _FPE_SQRTNEG            0x88
  95 #define _FPE_STACKOVERFLOW      0x8a
  96 #define _FPE_STACKUNDERFLOW     0x8b
  97 #define _FPE_EXPLICITGEN        0x8c    /* raise( SIGFPE ); */
  98
  99 #ifndef RC_INVOKED
 100
 101 #ifdef  __cplusplus
 102 extern "C" {
 103 #endif
 104
 105 /* Set the FPU control word as cw = (cw & ~unMask) | (unNew & unMask),
 106  * i.e. change the bits in unMask to have the values they have in unNew,
 107  * leaving other bits unchanged. */
 108 __MINGW_NOTHROW _CRTIMP unsigned int __cdecl _controlfp (unsigned int unNew, unsigned int unMask);
 109 __MINGW_NOTHROW _CRTIMP unsigned int __cdecl _control87 (unsigned int unNew, unsigned int unMask);
 110
 111
 112 __MINGW_NOTHROW _CRTIMP unsigned int __cdecl _clearfp (void);   /* Clear the FPU status word */
 113 __MINGW_NOTHROW _CRTIMP unsigned int __cdecl _statusfp (void);  /* Report the FPU status word */
 114 #define         _clear87        _clearfp
 115 #define         _status87       _statusfp
 116
 117
 118 /*
 119    MSVCRT.dll _fpreset initializes the control register to 0x27f,
 120    the status register to zero and the tag word to 0FFFFh.
 121    This differs from asm instruction finit/fninit which set control
 122    word to 0x37f (64 bit mantissa precison rather than 53 bit).
 123    By default, the mingw version of _fpreset sets fp control as
 124    per fninit. To use the MSVCRT.dll _fpreset, include CRT_fp8.o when
 125    building your application.
 126 */
 127 __MINGW_NOTHROW void __cdecl _fpreset (void);
 128 __MINGW_NOTHROW void __cdecl fpreset (void);
 129
 130 /* Global 'variable' for the current floating point error code. */
 131 __MINGW_NOTHROW _CRTIMP int * __cdecl __fpecode(void);
 132 #define _fpecode        (*(__fpecode()))
 133
 134 /*
 135  * IEEE recommended functions.  MS puts them in float.h
 136  * but they really belong in math.h.
 137  */
 138
 139 __MINGW_NOTHROW _CRTIMP double __cdecl _chgsign (double);
 140 __MINGW_NOTHROW _CRTIMP double __cdecl _copysign (double, double);
 141 __MINGW_NOTHROW _CRTIMP double __cdecl _logb (double);
 142 __MINGW_NOTHROW _CRTIMP double __cdecl _nextafter (double, double);
 143 __MINGW_NOTHROW _CRTIMP double __cdecl _scalb (double, long);
 144
 145 __MINGW_NOTHROW _CRTIMP int __cdecl _finite (double);
 146 __MINGW_NOTHROW _CRTIMP int __cdecl _fpclass (double);
 147 __MINGW_NOTHROW _CRTIMP int __cdecl _isnan (double);
 148
 149 #ifdef  __cplusplus
 150 }
 151 #endif
 152
 153 #endif  /* Not RC_INVOKED */
 154
 155 #endif  /* Not __STRICT_ANSI__ */
 156
 157 #endif /* _MINGW_FLOAT_H_ */