float.h

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//
// float.h
//
//      Copyright (c) Microsoft Corporation. All rights reserved.
//
// Implementation-defined values commonly used by sophisticated numerical
// (floating point) programs.
//
#pragma once
#define _INC_FLOAT

#include <corecrt.h>

_CRT_BEGIN_C_HEADER



#ifndef _CRT_MANAGED_FP_DEPRECATE
    #ifdef _CRT_MANAGED_FP_NO_DEPRECATE
        #define _CRT_MANAGED_FP_DEPRECATE
    #else
        #ifdef _M_CEE
            #define _CRT_MANAGED_FP_DEPRECATE _CRT_DEPRECATE_TEXT("Direct floating point control is not supported or reliable from within managed code. ")
        #else
            #define _CRT_MANAGED_FP_DEPRECATE
        #endif
    #endif
#endif


// Define the floating point precision used.
//
// For x86, results are in double precision (unless /arch:sse2 is used, in which
// case results are in source precision.
//
// For x64 and ARM, results are in source precision.
//
// If the compiler is invoked with /fp:fast, the compiler is allowed to use the
// fastest precision and even mix within a single function, so precision is
// indeterminable.
//
// Note that manipulating the floating point behavior using the float_control/
// fenv_access/fp_contract #pragmas may alter the actual floating point evaluation
// method, which may in turn invalidate the value of FLT_EVAL_METHOD.
#ifdef _M_FP_FAST
    #define FLT_EVAL_METHOD -1
#else
    #ifdef _M_IX86
        #if _M_IX86_FP >= 2
            #define FLT_EVAL_METHOD 0
        #else
            #define FLT_EVAL_METHOD 2
        #endif
    #else
        #define FLT_EVAL_METHOD 0
    #endif
#endif



//-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
//
// Constants
//
//-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
#define DBL_DECIMAL_DIG  17                      // # of decimal digits of rounding precision
#define DBL_DIG          15                      // # of decimal digits of precision
#define DBL_EPSILON      2.2204460492503131e-016 // smallest such that 1.0+DBL_EPSILON != 1.0
#define DBL_HAS_SUBNORM  1                       // type does support subnormal numbers
#define DBL_MANT_DIG     53                      // # of bits in mantissa
#define DBL_MAX          1.7976931348623158e+308 // max value
#define DBL_MAX_10_EXP   308                     // max decimal exponent
#define DBL_MAX_EXP      1024                    // max binary exponent
#define DBL_MIN          2.2250738585072014e-308 // min positive value
#define DBL_MIN_10_EXP   (-307)                  // min decimal exponent
#define DBL_MIN_EXP      (-1021)                 // min binary exponent
#define _DBL_RADIX       2                       // exponent radix
#define DBL_TRUE_MIN     4.9406564584124654e-324 // min positive value

#define FLT_DECIMAL_DIG  9                       // # of decimal digits of rounding precision
#define FLT_DIG          6                       // # of decimal digits of precision
#define FLT_EPSILON      1.192092896e-07F        // smallest such that 1.0+FLT_EPSILON != 1.0
#define FLT_HAS_SUBNORM  1                       // type does support subnormal numbers
#define FLT_GUARD        0
#define FLT_MANT_DIG     24                      // # of bits in mantissa
#define FLT_MAX          3.402823466e+38F        // max value
#define FLT_MAX_10_EXP   38                      // max decimal exponent
#define FLT_MAX_EXP      128                     // max binary exponent
#define FLT_MIN          1.175494351e-38F        // min normalized positive value
#define FLT_MIN_10_EXP   (-37)                   // min decimal exponent
#define FLT_MIN_EXP      (-125)                  // min binary exponent
#define FLT_NORMALIZE    0
#define FLT_RADIX        2                       // exponent radix
#define FLT_TRUE_MIN     1.401298464e-45F        // min positive value

#define LDBL_DIG         DBL_DIG                 // # of decimal digits of precision
#define LDBL_EPSILON     DBL_EPSILON             // smallest such that 1.0+LDBL_EPSILON != 1.0
#define LDBL_HAS_SUBNORM DBL_HAS_SUBNORM         // type does support subnormal numbers
#define LDBL_MANT_DIG    DBL_MANT_DIG            // # of bits in mantissa
#define LDBL_MAX         DBL_MAX                 // max value
#define LDBL_MAX_10_EXP  DBL_MAX_10_EXP          // max decimal exponent
#define LDBL_MAX_EXP     DBL_MAX_EXP             // max binary exponent
#define LDBL_MIN         DBL_MIN                 // min normalized positive value
#define LDBL_MIN_10_EXP  DBL_MIN_10_EXP          // min decimal exponent
#define LDBL_MIN_EXP     DBL_MIN_EXP             // min binary exponent
#define _LDBL_RADIX      _DBL_RADIX              // exponent radix
#define LDBL_TRUE_MIN    DBL_TRUE_MIN            // min positive value

#define DECIMAL_DIG      DBL_DECIMAL_DIG



//-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
//
// Flags
//
//-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
#define _SW_INEXACT     0x00000001              // Inexact (precision)
#define _SW_UNDERFLOW   0x00000002              // Underflow
#define _SW_OVERFLOW    0x00000004              // Overflow
#define _SW_ZERODIVIDE  0x00000008              // Divide by zero
#define _SW_INVALID     0x00000010              // Invalid
#define _SW_DENORMAL    0x00080000              // Denormal status bit

// New Control Bit that specifies the ambiguity in control word.
#define _EM_AMBIGUIOUS  0x80000000 // For backwards compatibility
#define _EM_AMBIGUOUS   0x80000000

// Abstract User Control Word Mask and bit definitions
#define _MCW_EM         0x0008001f              // Interrupt Exception Masks
#define _EM_INEXACT     0x00000001              //     inexact (precision)
#define _EM_UNDERFLOW   0x00000002              //     underflow
#define _EM_OVERFLOW    0x00000004              //     overflow
#define _EM_ZERODIVIDE  0x00000008              //     zero divide
#define _EM_INVALID     0x00000010              //     invalid
#define _EM_DENORMAL    0x00080000              // Denormal exception mask (_control87 only)

#define _MCW_RC         0x00000300              // Rounding Control
#define _RC_NEAR        0x00000000              //     near
#define _RC_DOWN        0x00000100              //     down
#define _RC_UP          0x00000200              //     up
#define _RC_CHOP        0x00000300              //     chop

// i386 specific definitions
#define _MCW_PC         0x00030000              // Precision Control
#define _PC_64          0x00000000              //     64 bits
#define _PC_53          0x00010000              //     53 bits
#define _PC_24          0x00020000              //     24 bits

#define _MCW_IC         0x00040000              // Infinity Control
#define _IC_AFFINE      0x00040000              //     affine
#define _IC_PROJECTIVE  0x00000000              //     projective

// RISC specific definitions
#define _MCW_DN         0x03000000              // Denormal Control
#define _DN_SAVE        0x00000000              //   save denormal results and operands
#define _DN_FLUSH       0x01000000              //   flush denormal results and operands to zero
#define _DN_FLUSH_OPERANDS_SAVE_RESULTS 0x02000000  // flush operands to zero and save results
#define _DN_SAVE_OPERANDS_FLUSH_RESULTS 0x03000000  // save operands and flush results to zero



// Invalid subconditions (_SW_INVALID also set)
#define _SW_UNEMULATED          0x0040  // Unemulated instruction
#define _SW_SQRTNEG             0x0080  // Square root of a negative 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);

// On x86 with arch:SSE2, the OS returns these exceptions
#define _FPE_MULTIPLE_TRAPS     0x8d
#define _FPE_MULTIPLE_FAULTS    0x8e



#define _FPCLASS_SNAN  0x0001  // signaling NaN
#define _FPCLASS_QNAN  0x0002  // quiet NaN
#define _FPCLASS_NINF  0x0004  // negative infinity
#define _FPCLASS_NN    0x0008  // negative normal
#define _FPCLASS_ND    0x0010  // negative denormal
#define _FPCLASS_NZ    0x0020  // -0
#define _FPCLASS_PZ    0x0040  // +0
#define _FPCLASS_PD    0x0080  // positive denormal
#define _FPCLASS_PN    0x0100  // positive normal
#define _FPCLASS_PINF  0x0200  // positive infinity



// Initial Control Word value
#if defined _M_IX86

    #define _CW_DEFAULT (_RC_NEAR + _PC_53 + _EM_INVALID + _EM_ZERODIVIDE + _EM_OVERFLOW + _EM_UNDERFLOW + _EM_INEXACT + _EM_DENORMAL)

#elif defined _M_X64 || defined _M_ARM || defined _M_ARM64

    #define _CW_DEFAULT (_RC_NEAR + _EM_INVALID + _EM_ZERODIVIDE + _EM_OVERFLOW + _EM_UNDERFLOW + _EM_INEXACT + _EM_DENORMAL)

#endif



//-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
//
// State Manipulation
//
//-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
// Note that reading or writing the floating point control or status words is
// not supported in managed code.
_CRT_MANAGED_FP_DEPRECATE
_ACRTIMP unsigned int __cdecl _clearfp(void);

#pragma warning(push)
#pragma warning(disable: 4141)

_CRT_MANAGED_FP_DEPRECATE _CRT_INSECURE_DEPRECATE(_controlfp_s)
_ACRTIMP unsigned int __cdecl _controlfp(
    _In_ unsigned int _NewValue,
    _In_ unsigned int _Mask
    );

#pragma warning(pop)

_CRT_MANAGED_FP_DEPRECATE
_ACRTIMP void __cdecl _set_controlfp(
    _In_ unsigned int _NewValue,
    _In_ unsigned int _Mask
    );

_CRT_MANAGED_FP_DEPRECATE
_ACRTIMP errno_t __cdecl _controlfp_s(
    _Out_opt_ unsigned int* _CurrentState,
    _In_      unsigned int  _NewValue,
    _In_      unsigned int  _Mask
    );

_CRT_MANAGED_FP_DEPRECATE
_ACRTIMP unsigned int __cdecl _statusfp(void);

_CRT_MANAGED_FP_DEPRECATE
_ACRTIMP void __cdecl _fpreset(void);

#ifdef _M_IX86

    _CRT_MANAGED_FP_DEPRECATE
    _ACRTIMP void __cdecl _statusfp2(
        _Out_opt_ unsigned int* _X86Status,
        _Out_opt_ unsigned int* _SSE2Status
        );

#endif

#define _clear87        _clearfp
#define _status87       _statusfp

_CRT_MANAGED_FP_DEPRECATE
_ACRTIMP unsigned int __cdecl _control87(
    _In_ unsigned int _NewValue,
    _In_ unsigned int _Mask
    );

#ifdef _M_IX86
    _CRT_MANAGED_FP_DEPRECATE
    _ACRTIMP int __cdecl __control87_2(
        _In_      unsigned int  _NewValue,
        _In_      unsigned int  _Mask,
        _Out_opt_ unsigned int* _X86ControlWord,
        _Out_opt_ unsigned int* _Sse2ControlWord
        );
#endif

// Global variable holding floating point error code
_Check_return_
_ACRTIMP int* __cdecl __fpecode(void);

#define _fpecode (*__fpecode())

_Check_return_
_ACRTIMP int __cdecl __fpe_flt_rounds(void);

#define FLT_ROUNDS   (__fpe_flt_rounds())
#define _DBL_ROUNDS  FLT_ROUNDS
#define _LDBL_ROUNDS _DBL_ROUNDS



//-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
//
// IEEE Recommended Functions
//
//-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
_Check_return_ _ACRTIMP double __cdecl _copysign(_In_ double _Number, _In_ double _Sign);
_Check_return_ _ACRTIMP double __cdecl _chgsign(_In_ double _X);
_Check_return_ _ACRTIMP double __cdecl _scalb(_In_ double _X, _In_ long _Y);
_Check_return_ _ACRTIMP double __cdecl _logb(_In_ double _X);
_Check_return_ _ACRTIMP double __cdecl _nextafter(_In_ double _X, _In_ double _Y);
_Check_return_ _ACRTIMP int    __cdecl _finite(_In_ double _X);
_Check_return_ _ACRTIMP int    __cdecl _isnan(_In_ double _X);
_Check_return_ _ACRTIMP int    __cdecl _fpclass(_In_ double _X);

#ifdef _M_X64
    _Check_return_ _ACRTIMP float __cdecl _scalbf(_In_ float _X, _In_ long _Y);
#endif



//-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
//
// Nonstandard Names for Compatibility
//
//-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
#if _CRT_INTERNAL_NONSTDC_NAMES

    #define clear87   _clear87
    #define status87  _status87
    #define control87 _control87

    _CRT_MANAGED_FP_DEPRECATE
    _ACRTIMP void __cdecl fpreset(void);

    #define DBL_RADIX          _DBL_RADIX
    #define DBL_ROUNDS         _DBL_ROUNDS

    #define LDBL_RADIX         _LDBL_RADIX
    #define LDBL_ROUNDS        _LDBL_ROUNDS

    // For backwards compatibility with the old spelling
    #define EM_AMBIGUIOUS      _EM_AMBIGUOUS
    #define EM_AMBIGUOUS       _EM_AMBIGUOUS

    #define MCW_EM             _MCW_EM
    #define EM_INVALID         _EM_INVALID
    #define EM_DENORMAL        _EM_DENORMAL
    #define EM_ZERODIVIDE      _EM_ZERODIVIDE
    #define EM_OVERFLOW        _EM_OVERFLOW
    #define EM_UNDERFLOW       _EM_UNDERFLOW
    #define EM_INEXACT         _EM_INEXACT

    #define MCW_IC             _MCW_IC
    #define IC_AFFINE          _IC_AFFINE
    #define IC_PROJECTIVE      _IC_PROJECTIVE

    #define MCW_RC             _MCW_RC
    #define RC_CHOP            _RC_CHOP
    #define RC_UP              _RC_UP
    #define RC_DOWN            _RC_DOWN
    #define RC_NEAR            _RC_NEAR

    #define MCW_PC             _MCW_PC
    #define PC_24              _PC_24
    #define PC_53              _PC_53
    #define PC_64              _PC_64

    #define CW_DEFAULT         _CW_DEFAULT

    #define SW_INVALID         _SW_INVALID
    #define SW_DENORMAL        _SW_DENORMAL
    #define SW_ZERODIVIDE      _SW_ZERODIVIDE
    #define SW_OVERFLOW        _SW_OVERFLOW
    #define SW_UNDERFLOW       _SW_UNDERFLOW
    #define SW_INEXACT         _SW_INEXACT

    #define SW_UNEMULATED      _SW_UNEMULATED
    #define SW_SQRTNEG         _SW_SQRTNEG
    #define SW_STACKOVERFLOW   _SW_STACKOVERFLOW
    #define SW_STACKUNDERFLOW  _SW_STACKUNDERFLOW

    #define FPE_INVALID        _FPE_INVALID
    #define FPE_DENORMAL       _FPE_DENORMAL
    #define FPE_ZERODIVIDE     _FPE_ZERODIVIDE
    #define FPE_OVERFLOW       _FPE_OVERFLOW
    #define FPE_UNDERFLOW      _FPE_UNDERFLOW
    #define FPE_INEXACT        _FPE_INEXACT

    #define FPE_UNEMULATED     _FPE_UNEMULATED
    #define FPE_SQRTNEG        _FPE_SQRTNEG
    #define FPE_STACKOVERFLOW  _FPE_STACKOVERFLOW
    #define FPE_STACKUNDERFLOW _FPE_STACKUNDERFLOW

    #define FPE_EXPLICITGEN    _FPE_EXPLICITGEN

#endif // _CRT_INTERNAL_NONSTDC_NAMES



_CRT_END_C_HEADER