xref: /reactos/sdk/include/crt/float.h (revision 7e22dc05)
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 /* _statusfp bit flags */
81 #define _SW_INEXACT    0x00000001  /* inexact (precision) */
82 #define _SW_UNDERFLOW  0x00000002  /* underflow */
83 #define _SW_OVERFLOW   0x00000004  /* overflow */
84 #define _SW_ZERODIVIDE 0x00000008  /* zero divide */
85 #define _SW_INVALID    0x00000010  /* invalid */
86 #define _SW_DENORMAL   0x00080000  /* denormal status bit */
87 
88 /* invalid subconditions (_SW_INVALID also set) */
89 #define _SW_UNEMULATED		0x0040  /* unemulated instruction */
90 #define _SW_SQRTNEG		0x0080  /* square root of a neg number */
91 #define _SW_STACKOVERFLOW	0x0200  /* FP stack overflow */
92 #define _SW_STACKUNDERFLOW	0x0400  /* FP stack underflow */
93 
94 /*  Floating point error signals and return codes */
95 #define _FPE_INVALID		0x81
96 #define _FPE_DENORMAL		0x82
97 #define _FPE_ZERODIVIDE		0x83
98 #define _FPE_OVERFLOW		0x84
99 #define _FPE_UNDERFLOW		0x85
100 #define _FPE_INEXACT		0x86
101 #define _FPE_UNEMULATED		0x87
102 #define _FPE_SQRTNEG		0x88
103 #define _FPE_STACKOVERFLOW	0x8a
104 #define _FPE_STACKUNDERFLOW	0x8b
105 #define _FPE_EXPLICITGEN	0x8c    /* raise( SIGFPE ); */
106 
107 #ifndef RC_INVOKED
108 
109 #ifdef	__cplusplus
110 extern "C" {
111 #endif
112 
113 /* Set the FPU control word as cw = (cw & ~unMask) | (unNew & unMask),
114  * i.e. change the bits in unMask to have the values they have in unNew,
115  * leaving other bits unchanged. */
116 
117 __MINGW_NOTHROW
118 _CRTIMP
119 unsigned int
120 __cdecl
121 _controlfp(
122   _In_ unsigned int unNew,
123   _In_ unsigned int unMask);
124 
125 __MINGW_NOTHROW
126 _CRTIMP
127 unsigned int
128 __cdecl
129 _control87(
130   _In_ unsigned int unNew,
131   _In_ unsigned int unMask);
132 
133 __MINGW_NOTHROW _CRTIMP unsigned int __cdecl _clearfp (void);	/* Clear the FPU status word */
134 __MINGW_NOTHROW _CRTIMP unsigned int __cdecl _statusfp (void);	/* Report the FPU status word */
135 #define		_clear87	_clearfp
136 #define		_status87	_statusfp
137 
138 
139 /*
140    MSVCRT.dll _fpreset initializes the control register to 0x27f,
141    the status register to zero and the tag word to 0FFFFh.
142    This differs from asm instruction finit/fninit which set control
143    word to 0x37f (64 bit mantissa precison rather than 53 bit).
144    By default, the mingw version of _fpreset sets fp control as
145    per fninit. To use the MSVCRT.dll _fpreset, include CRT_fp8.o when
146    building your application.
147 */
148 __MINGW_NOTHROW void __cdecl _fpreset (void);
149 __MINGW_NOTHROW void __cdecl fpreset (void);
150 
151 /* Global 'variable' for the current floating point error code. */
152 __MINGW_NOTHROW _CRTIMP int * __cdecl __fpecode(void);
153 #define	_fpecode	(*(__fpecode()))
154 
155 /*
156  * IEEE recommended functions.  MS puts them in float.h
157  * but they really belong in math.h.
158  */
159 
160 _Check_return_
161 __MINGW_NOTHROW
162 _CRTIMP
163 double
164 __cdecl
165 _chgsign(
166   _In_ double);
167 
168 _Check_return_
169 __MINGW_NOTHROW
170 _CRTIMP
171 double
172 __cdecl
173 _copysign(
174   _In_ double,
175   _In_ double);
176 
177 _Check_return_
178 __MINGW_NOTHROW
179 _CRTIMP
180 double
181 __cdecl
182 _logb(
183   _In_ double);
184 
185 _Check_return_
186 __MINGW_NOTHROW
187 _CRTIMP
188 double
189 __cdecl
190 _nextafter(
191   _In_ double,
192   _In_ double);
193 
194 _Check_return_
195 __MINGW_NOTHROW
196 _CRTIMP
197 double
198 __cdecl
199 _scalb(
200   _In_ double,
201   _In_ long);
202 
203 _Check_return_
204 __MINGW_NOTHROW
205 _CRTIMP
206 int
207 __cdecl
208 _finite(
209   _In_ double);
210 
211 _Check_return_
212 __MINGW_NOTHROW
213 _CRTIMP
214 int
215 __cdecl
216 _fpclass(
217   _In_ double);
218 
219 _Check_return_
220 __MINGW_NOTHROW
221 _CRTIMP
222 int
223 __cdecl
224 _isnan(
225   _In_ double);
226 
227 #ifdef __cplusplus
228 }
229 #endif
230 
231 #endif	/* Not RC_INVOKED */
232 
233 #endif	/* Not __STRICT_ANSI__ */
234 
235 #endif /* _MINGW_FLOAT_H_ */
236