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1
2/*
3===============================================================================
4
5This C header file is part of the SoftFloat IEC/IEEE Floating-point
6Arithmetic Package, Release 2.
7
8Written by John R. Hauser. This work was made possible in part by the
9International Computer Science Institute, located at Suite 600, 1947 Center
10Street, Berkeley, California 94704. Funding was partially provided by the
11National Science Foundation under grant MIP-9311980. The original version
12of this code was written as part of a project to build a fixed-point vector
13processor in collaboration with the University of California at Berkeley,
14overseen by Profs. Nelson Morgan and John Wawrzynek. More information
15is available through the Web page
16http://www.jhauser.us/arithmetic/SoftFloat-2b/SoftFloat-source.txt
17
18THIS SOFTWARE IS DISTRIBUTED AS IS, FOR FREE. Although reasonable effort
19has been made to avoid it, THIS SOFTWARE MAY CONTAIN FAULTS THAT WILL AT
20TIMES RESULT IN INCORRECT BEHAVIOR. USE OF THIS SOFTWARE IS RESTRICTED TO
21PERSONS AND ORGANIZATIONS WHO CAN AND WILL TAKE FULL RESPONSIBILITY FOR ANY
22AND ALL LOSSES, COSTS, OR OTHER PROBLEMS ARISING FROM ITS USE.
23
24Derivative works are acceptable, even for commercial purposes, so long as
25(1) they include prominent notice that the work is derivative, and (2) they
26include prominent notice akin to these three paragraphs for those parts of
27this code that are retained.
28
29===============================================================================
30*/
31
32#ifndef __SOFTFLOAT_H__
33#define __SOFTFLOAT_H__
34
35
36/*
37-------------------------------------------------------------------------------
38The macro `FLOATX80' must be defined to enable the extended double-precision
39floating-point format `floatx80'. If this macro is not defined, the
40`floatx80' type will not be defined, and none of the functions that either
41input or output the `floatx80' type will be defined.
42-------------------------------------------------------------------------------
43*/
44#ifdef CONFIG_FPE_NWFPE_XP
45#define FLOATX80
46#endif
47
48/*
49-------------------------------------------------------------------------------
50Software IEC/IEEE floating-point types.
51-------------------------------------------------------------------------------
52*/
53typedef u32 float32;
54typedef u64 float64;
55typedef struct {
56#ifdef __ARMEB__
57 u16 __padding;
58 u16 high;
59#else
60 u16 high;
61 u16 __padding;
62#endif
63 u64 low;
64} __attribute__ ((packed,aligned(4))) floatx80;
65
66/*
67-------------------------------------------------------------------------------
68Software IEC/IEEE floating-point underflow tininess-detection mode.
69-------------------------------------------------------------------------------
70*/
71extern signed char float_detect_tininess;
72enum {
73 float_tininess_after_rounding = 0,
74 float_tininess_before_rounding = 1
75};
76
77/*
78-------------------------------------------------------------------------------
79Software IEC/IEEE floating-point rounding mode.
80-------------------------------------------------------------------------------
81*/
82//extern int8 float_rounding_mode;
83enum {
84 float_round_nearest_even = 0,
85 float_round_to_zero = 1,
86 float_round_down = 2,
87 float_round_up = 3
88};
89
90/*
91-------------------------------------------------------------------------------
92Software IEC/IEEE floating-point exception flags.
93-------------------------------------------------------------------------------
94enum {
95 float_flag_inexact = 1,
96 float_flag_underflow = 2,
97 float_flag_overflow = 4,
98 float_flag_divbyzero = 8,
99 float_flag_invalid = 16
100};
101
102ScottB: November 4, 1998
103Changed the enumeration to match the bit order in the FPA11.
104*/
105
106enum {
107 float_flag_invalid = 1,
108 float_flag_divbyzero = 2,
109 float_flag_overflow = 4,
110 float_flag_underflow = 8,
111 float_flag_inexact = 16
112};
113
114/*
115-------------------------------------------------------------------------------
116Routine to raise any or all of the software IEC/IEEE floating-point
117exception flags.
118-------------------------------------------------------------------------------
119*/
120void float_raise( signed char );
121
122/*
123-------------------------------------------------------------------------------
124Software IEC/IEEE integer-to-floating-point conversion routines.
125-------------------------------------------------------------------------------
126*/
127float32 int32_to_float32( struct roundingData *, signed int );
128float64 int32_to_float64( signed int );
129#ifdef FLOATX80
130floatx80 int32_to_floatx80( signed int );
131#endif
132
133/*
134-------------------------------------------------------------------------------
135Software IEC/IEEE single-precision conversion routines.
136-------------------------------------------------------------------------------
137*/
138signed int float32_to_int32( struct roundingData *, float32 );
139signed int float32_to_int32_round_to_zero( float32 );
140float64 float32_to_float64( float32 );
141#ifdef FLOATX80
142floatx80 float32_to_floatx80( float32 );
143#endif
144
145/*
146-------------------------------------------------------------------------------
147Software IEC/IEEE single-precision operations.
148-------------------------------------------------------------------------------
149*/
150float32 float32_round_to_int( struct roundingData*, float32 );
151float32 float32_add( struct roundingData *, float32, float32 );
152float32 float32_sub( struct roundingData *, float32, float32 );
153float32 float32_mul( struct roundingData *, float32, float32 );
154float32 float32_div( struct roundingData *, float32, float32 );
155float32 float32_rem( struct roundingData *, float32, float32 );
156float32 float32_sqrt( struct roundingData*, float32 );
157char float32_eq( float32, float32 );
158char float32_le( float32, float32 );
159char float32_lt( float32, float32 );
160char float32_eq_signaling( float32, float32 );
161char float32_le_quiet( float32, float32 );
162char float32_lt_quiet( float32, float32 );
163char float32_is_signaling_nan( float32 );
164
165/*
166-------------------------------------------------------------------------------
167Software IEC/IEEE double-precision conversion routines.
168-------------------------------------------------------------------------------
169*/
170signed int float64_to_int32( struct roundingData *, float64 );
171signed int float64_to_int32_round_to_zero( float64 );
172float32 float64_to_float32( struct roundingData *, float64 );
173#ifdef FLOATX80
174floatx80 float64_to_floatx80( float64 );
175#endif
176
177/*
178-------------------------------------------------------------------------------
179Software IEC/IEEE double-precision operations.
180-------------------------------------------------------------------------------
181*/
182float64 float64_round_to_int( struct roundingData *, float64 );
183float64 float64_add( struct roundingData *, float64, float64 );
184float64 float64_sub( struct roundingData *, float64, float64 );
185float64 float64_mul( struct roundingData *, float64, float64 );
186float64 float64_div( struct roundingData *, float64, float64 );
187float64 float64_rem( struct roundingData *, float64, float64 );
188float64 float64_sqrt( struct roundingData *, float64 );
189char float64_eq( float64, float64 );
190char float64_le( float64, float64 );
191char float64_lt( float64, float64 );
192char float64_eq_signaling( float64, float64 );
193char float64_le_quiet( float64, float64 );
194char float64_lt_quiet( float64, float64 );
195char float64_is_signaling_nan( float64 );
196
197#ifdef FLOATX80
198
199/*
200-------------------------------------------------------------------------------
201Software IEC/IEEE extended double-precision conversion routines.
202-------------------------------------------------------------------------------
203*/
204signed int floatx80_to_int32( struct roundingData *, floatx80 );
205signed int floatx80_to_int32_round_to_zero( floatx80 );
206float32 floatx80_to_float32( struct roundingData *, floatx80 );
207float64 floatx80_to_float64( struct roundingData *, floatx80 );
208
209/*
210-------------------------------------------------------------------------------
211Software IEC/IEEE extended double-precision operations.
212-------------------------------------------------------------------------------
213*/
214floatx80 floatx80_round_to_int( struct roundingData *, floatx80 );
215floatx80 floatx80_add( struct roundingData *, floatx80, floatx80 );
216floatx80 floatx80_sub( struct roundingData *, floatx80, floatx80 );
217floatx80 floatx80_mul( struct roundingData *, floatx80, floatx80 );
218floatx80 floatx80_div( struct roundingData *, floatx80, floatx80 );
219floatx80 floatx80_rem( struct roundingData *, floatx80, floatx80 );
220floatx80 floatx80_sqrt( struct roundingData *, floatx80 );
221char floatx80_eq( floatx80, floatx80 );
222char floatx80_le( floatx80, floatx80 );
223char floatx80_lt( floatx80, floatx80 );
224char floatx80_eq_signaling( floatx80, floatx80 );
225char floatx80_le_quiet( floatx80, floatx80 );
226char floatx80_lt_quiet( floatx80, floatx80 );
227char floatx80_is_signaling_nan( floatx80 );
228
229extern flag floatx80_is_nan(floatx80);
230
231#endif
232
233static inline flag extractFloat32Sign(float32 a)
234{
235 return a >> 31;
236}
237
238static inline flag float32_eq_nocheck(float32 a, float32 b)
239{
240 return (a == b) || ((bits32) ((a | b) << 1) == 0);
241}
242
243static inline flag float32_lt_nocheck(float32 a, float32 b)
244{
245 flag aSign, bSign;
246
247 aSign = extractFloat32Sign(a);
248 bSign = extractFloat32Sign(b);
249 if (aSign != bSign)
250 return aSign && ((bits32) ((a | b) << 1) != 0);
251 return (a != b) && (aSign ^ (a < b));
252}
253
254static inline flag extractFloat64Sign(float64 a)
255{
256 return a >> 63;
257}
258
259static inline flag float64_eq_nocheck(float64 a, float64 b)
260{
261 return (a == b) || ((bits64) ((a | b) << 1) == 0);
262}
263
264static inline flag float64_lt_nocheck(float64 a, float64 b)
265{
266 flag aSign, bSign;
267
268 aSign = extractFloat64Sign(a);
269 bSign = extractFloat64Sign(b);
270 if (aSign != bSign)
271 return aSign && ((bits64) ((a | b) << 1) != 0);
272 return (a != b) && (aSign ^ (a < b));
273}
274
275extern flag float32_is_nan( float32 a );
276extern flag float64_is_nan( float64 a );
277
278extern int32 float64_to_uint32( struct roundingData *roundData, float64 a );
279extern int32 float64_to_uint32_round_to_zero( float64 a );
280
281#endif