xref: /reactos/sdk/include/crt/float.h (revision 8a978a17)
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 #ifndef _MINGW_FLOAT_H_
20 #define _MINGW_FLOAT_H_
21 
22 #if defined(__GNUC__)
23 #include "mingw32/gcc_float.h"
24 #elif defined(_MSC_VER)
25 #include "msc/msc_float.h"
26 #else
27 #error
28 #endif
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 
109 __MINGW_NOTHROW
110 _CRTIMP
111 unsigned int
112 __cdecl
113 _controlfp(
114   _In_ unsigned int unNew,
115   _In_ unsigned int unMask);
116 
117 __MINGW_NOTHROW
118 _CRTIMP
119 unsigned int
120 __cdecl
121 _control87(
122   _In_ unsigned int unNew,
123   _In_ unsigned int unMask);
124 
125 __MINGW_NOTHROW _CRTIMP unsigned int __cdecl _clearfp (void);	/* Clear the FPU status word */
126 __MINGW_NOTHROW _CRTIMP unsigned int __cdecl _statusfp (void);	/* Report the FPU status word */
127 #define		_clear87	_clearfp
128 #define		_status87	_statusfp
129 
130 
131 /*
132    MSVCRT.dll _fpreset initializes the control register to 0x27f,
133    the status register to zero and the tag word to 0FFFFh.
134    This differs from asm instruction finit/fninit which set control
135    word to 0x37f (64 bit mantissa precison rather than 53 bit).
136    By default, the mingw version of _fpreset sets fp control as
137    per fninit. To use the MSVCRT.dll _fpreset, include CRT_fp8.o when
138    building your application.
139 */
140 __MINGW_NOTHROW void __cdecl _fpreset (void);
141 __MINGW_NOTHROW void __cdecl fpreset (void);
142 
143 /* Global 'variable' for the current floating point error code. */
144 __MINGW_NOTHROW _CRTIMP int * __cdecl __fpecode(void);
145 #define	_fpecode	(*(__fpecode()))
146 
147 /*
148  * IEEE recommended functions.  MS puts them in float.h
149  * but they really belong in math.h.
150  */
151 
152 _Check_return_
153 __MINGW_NOTHROW
154 _CRTIMP
155 double
156 __cdecl
157 _chgsign(
158   _In_ double);
159 
160 _Check_return_
161 __MINGW_NOTHROW
162 _CRTIMP
163 double
164 __cdecl
165 _copysign(
166   _In_ double,
167   _In_ double);
168 
169 _Check_return_
170 __MINGW_NOTHROW
171 _CRTIMP
172 double
173 __cdecl
174 _logb(
175   _In_ double);
176 
177 _Check_return_
178 __MINGW_NOTHROW
179 _CRTIMP
180 double
181 __cdecl
182 _nextafter(
183   _In_ double,
184   _In_ double);
185 
186 _Check_return_
187 __MINGW_NOTHROW
188 _CRTIMP
189 double
190 __cdecl
191 _scalb(
192   _In_ double,
193   _In_ long);
194 
195 _Check_return_
196 __MINGW_NOTHROW
197 _CRTIMP
198 int
199 __cdecl
200 _finite(
201   _In_ double);
202 
203 _Check_return_
204 __MINGW_NOTHROW
205 _CRTIMP
206 int
207 __cdecl
208 _fpclass(
209   _In_ double);
210 
211 _Check_return_
212 __MINGW_NOTHROW
213 _CRTIMP
214 int
215 __cdecl
216 _isnan(
217   _In_ double);
218 
219 #ifdef __cplusplus
220 }
221 #endif
222 
223 #endif	/* Not RC_INVOKED */
224 
225 #endif	/* Not __STRICT_ANSI__ */
226 
227 #endif /* _MINGW_FLOAT_H_ */
228