xref: /linux/include/math-emu/soft-fp.h (revision f3d9478b2ce468c3115b02ecae7e975990697f15)
1 /* Software floating-point emulation.
2    Copyright (C) 1997,1998,1999 Free Software Foundation, Inc.
3    This file is part of the GNU C Library.
4    Contributed by Richard Henderson (rth@cygnus.com),
5 		  Jakub Jelinek (jj@ultra.linux.cz),
6 		  David S. Miller (davem@redhat.com) and
7 		  Peter Maydell (pmaydell@chiark.greenend.org.uk).
8 
9    The GNU C Library is free software; you can redistribute it and/or
10    modify it under the terms of the GNU Library General Public License as
11    published by the Free Software Foundation; either version 2 of the
12    License, or (at your option) any later version.
13 
14    The GNU C Library is distributed in the hope that it will be useful,
15    but WITHOUT ANY WARRANTY; without even the implied warranty of
16    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
17    Library General Public License for more details.
18 
19    You should have received a copy of the GNU Library General Public
20    License along with the GNU C Library; see the file COPYING.LIB.  If
21    not, write to the Free Software Foundation, Inc.,
22    59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.  */
23 
24 #ifndef __MATH_EMU_SOFT_FP_H__
25 #define __MATH_EMU_SOFT_FP_H__
26 
27 #include <asm/sfp-machine.h>
28 
29 /* Allow sfp-machine to have its own byte order definitions. */
30 #ifndef __BYTE_ORDER
31 #include <endian.h>
32 #endif
33 
34 #define _FP_WORKBITS		3
35 #define _FP_WORK_LSB		((_FP_W_TYPE)1 << 3)
36 #define _FP_WORK_ROUND		((_FP_W_TYPE)1 << 2)
37 #define _FP_WORK_GUARD		((_FP_W_TYPE)1 << 1)
38 #define _FP_WORK_STICKY		((_FP_W_TYPE)1 << 0)
39 
40 #ifndef FP_RND_NEAREST
41 # define FP_RND_NEAREST		0
42 # define FP_RND_ZERO		1
43 # define FP_RND_PINF		2
44 # define FP_RND_MINF		3
45 #ifndef FP_ROUNDMODE
46 # define FP_ROUNDMODE		FP_RND_NEAREST
47 #endif
48 #endif
49 
50 /* By default don't care about exceptions. */
51 #ifndef FP_EX_INVALID
52 #define FP_EX_INVALID		0
53 #endif
54 #ifndef FP_EX_OVERFLOW
55 #define FP_EX_OVERFLOW		0
56 #endif
57 #ifndef FP_EX_UNDERFLOW
58 #define FP_EX_UNDERFLOW
59 #endif
60 #ifndef FP_EX_DIVZERO
61 #define FP_EX_DIVZERO		0
62 #endif
63 #ifndef FP_EX_INEXACT
64 #define FP_EX_INEXACT		0
65 #endif
66 #ifndef FP_EX_DENORM
67 #define FP_EX_DENORM		0
68 #endif
69 
70 #ifdef _FP_DECL_EX
71 #define FP_DECL_EX					\
72   int _fex = 0;						\
73   _FP_DECL_EX
74 #else
75 #define FP_DECL_EX int _fex = 0
76 #endif
77 
78 #ifndef FP_INIT_ROUNDMODE
79 #define FP_INIT_ROUNDMODE do {} while (0)
80 #endif
81 
82 #ifndef FP_HANDLE_EXCEPTIONS
83 #define FP_HANDLE_EXCEPTIONS do {} while (0)
84 #endif
85 
86 /* By default we never flush denormal input operands to signed zero. */
87 #ifndef FP_DENORM_ZERO
88 #define FP_DENORM_ZERO 0
89 #endif
90 
91 #ifndef FP_INHIBIT_RESULTS
92 /* By default we write the results always.
93  * sfp-machine may override this and e.g.
94  * check if some exceptions are unmasked
95  * and inhibit it in such a case.
96  */
97 #define FP_INHIBIT_RESULTS 0
98 #endif
99 
100 #define FP_SET_EXCEPTION(ex)				\
101   _fex |= (ex)
102 
103 #define FP_UNSET_EXCEPTION(ex)				\
104   _fex &= ~(ex)
105 
106 #define FP_CLEAR_EXCEPTIONS				\
107   _fex = 0
108 
109 #define _FP_ROUND_NEAREST(wc, X)			\
110 do {							\
111     if ((_FP_FRAC_LOW_##wc(X) & 15) != _FP_WORK_ROUND)	\
112       _FP_FRAC_ADDI_##wc(X, _FP_WORK_ROUND);		\
113 } while (0)
114 
115 #define _FP_ROUND_ZERO(wc, X)		0
116 
117 #define _FP_ROUND_PINF(wc, X)				\
118 do {							\
119     if (!X##_s && (_FP_FRAC_LOW_##wc(X) & 7))		\
120       _FP_FRAC_ADDI_##wc(X, _FP_WORK_LSB);		\
121 } while (0)
122 
123 #define _FP_ROUND_MINF(wc, X)				\
124 do {							\
125     if (X##_s && (_FP_FRAC_LOW_##wc(X) & 7))		\
126       _FP_FRAC_ADDI_##wc(X, _FP_WORK_LSB);		\
127 } while (0)
128 
129 #define _FP_ROUND(wc, X)			\
130 do {						\
131 	if (_FP_FRAC_LOW_##wc(X) & 7)		\
132 	  FP_SET_EXCEPTION(FP_EX_INEXACT);	\
133 	switch (FP_ROUNDMODE)			\
134 	{					\
135 	  case FP_RND_NEAREST:			\
136 	    _FP_ROUND_NEAREST(wc,X);		\
137 	    break;				\
138 	  case FP_RND_ZERO:			\
139 	    _FP_ROUND_ZERO(wc,X);		\
140 	    break;				\
141 	  case FP_RND_PINF:			\
142 	    _FP_ROUND_PINF(wc,X);		\
143 	    break;				\
144 	  case FP_RND_MINF:			\
145 	    _FP_ROUND_MINF(wc,X);		\
146 	    break;				\
147 	}					\
148 } while (0)
149 
150 #define FP_CLS_NORMAL		0
151 #define FP_CLS_ZERO		1
152 #define FP_CLS_INF		2
153 #define FP_CLS_NAN		3
154 
155 #define _FP_CLS_COMBINE(x,y)	(((x) << 2) | (y))
156 
157 #include <math-emu/op-1.h>
158 #include <math-emu/op-2.h>
159 #include <math-emu/op-4.h>
160 #include <math-emu/op-8.h>
161 #include <math-emu/op-common.h>
162 
163 /* Sigh.  Silly things longlong.h needs.  */
164 #define UWtype		_FP_W_TYPE
165 #define W_TYPE_SIZE	_FP_W_TYPE_SIZE
166 
167 typedef int SItype __attribute__((mode(SI)));
168 typedef int DItype __attribute__((mode(DI)));
169 typedef unsigned int USItype __attribute__((mode(SI)));
170 typedef unsigned int UDItype __attribute__((mode(DI)));
171 #if _FP_W_TYPE_SIZE == 32
172 typedef unsigned int UHWtype __attribute__((mode(HI)));
173 #elif _FP_W_TYPE_SIZE == 64
174 typedef USItype UHWtype;
175 #endif
176 
177 #ifndef umul_ppmm
178 #include <stdlib/longlong.h>
179 #endif
180 
181 #endif /* __MATH_EMU_SOFT_FP_H__ */
182