fcnvfxt.c revision 1.5 1 1.5 skrll /* $NetBSD: fcnvfxt.c,v 1.5 2012/02/04 17:03:09 skrll Exp $ */
2 1.1 fredette
3 1.4 skrll /* $OpenBSD: fcnvfxt.c,v 1.8 2010/07/30 18:05:23 kettenis Exp $ */
4 1.1 fredette
5 1.1 fredette /*
6 1.1 fredette * Copyright 1996 1995 by Open Software Foundation, Inc.
7 1.1 fredette * All Rights Reserved
8 1.1 fredette *
9 1.1 fredette * Permission to use, copy, modify, and distribute this software and
10 1.1 fredette * its documentation for any purpose and without fee is hereby granted,
11 1.1 fredette * provided that the above copyright notice appears in all copies and
12 1.1 fredette * that both the copyright notice and this permission notice appear in
13 1.1 fredette * supporting documentation.
14 1.1 fredette *
15 1.1 fredette * OSF DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE
16 1.1 fredette * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
17 1.1 fredette * FOR A PARTICULAR PURPOSE.
18 1.1 fredette *
19 1.1 fredette * IN NO EVENT SHALL OSF BE LIABLE FOR ANY SPECIAL, INDIRECT, OR
20 1.1 fredette * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
21 1.1 fredette * LOSS OF USE, DATA OR PROFITS, WHETHER IN ACTION OF CONTRACT,
22 1.1 fredette * NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
23 1.1 fredette * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
24 1.1 fredette *
25 1.1 fredette */
26 1.1 fredette /*
27 1.1 fredette * pmk1.1
28 1.1 fredette */
29 1.1 fredette /*
30 1.1 fredette * (c) Copyright 1986 HEWLETT-PACKARD COMPANY
31 1.1 fredette *
32 1.1 fredette * To anyone who acknowledges that this file is provided "AS IS"
33 1.1 fredette * without any express or implied warranty:
34 1.1 fredette * permission to use, copy, modify, and distribute this file
35 1.1 fredette * for any purpose is hereby granted without fee, provided that
36 1.1 fredette * the above copyright notice and this notice appears in all
37 1.1 fredette * copies, and that the name of Hewlett-Packard Company not be
38 1.1 fredette * used in advertising or publicity pertaining to distribution
39 1.1 fredette * of the software without specific, written prior permission.
40 1.1 fredette * Hewlett-Packard Company makes no representations about the
41 1.1 fredette * suitability of this software for any purpose.
42 1.1 fredette */
43 1.2 lukem
44 1.2 lukem #include <sys/cdefs.h>
45 1.5 skrll __KERNEL_RCSID(0, "$NetBSD: fcnvfxt.c,v 1.5 2012/02/04 17:03:09 skrll Exp $");
46 1.1 fredette
47 1.1 fredette #include "../spmath/float.h"
48 1.1 fredette #include "../spmath/sgl_float.h"
49 1.1 fredette #include "../spmath/dbl_float.h"
50 1.1 fredette #include "../spmath/cnv_float.h"
51 1.1 fredette
52 1.1 fredette /*
53 1.1 fredette * Convert single floating-point to single fixed-point format
54 1.1 fredette * with truncated result
55 1.1 fredette */
56 1.1 fredette /*ARGSUSED*/
57 1.1 fredette int
58 1.5 skrll sgl_to_sgl_fcnvfxt(sgl_floating_point *srcptr, int *dstptr,
59 1.5 skrll unsigned int *status)
60 1.1 fredette {
61 1.1 fredette register unsigned int src, temp;
62 1.1 fredette register int src_exponent, result;
63 1.1 fredette
64 1.1 fredette src = *srcptr;
65 1.1 fredette src_exponent = Sgl_exponent(src) - SGL_BIAS;
66 1.1 fredette
67 1.1 fredette /*
68 1.1 fredette * Test for overflow
69 1.1 fredette */
70 1.1 fredette if (src_exponent > SGL_FX_MAX_EXP) {
71 1.1 fredette /* check for MININT */
72 1.1 fredette if ((src_exponent > SGL_FX_MAX_EXP + 1) ||
73 1.1 fredette Sgl_isnotzero_mantissa(src) || Sgl_iszero_sign(src)) {
74 1.4 skrll if (Sgl_iszero_sign(src)) result = 0x7fffffff;
75 1.4 skrll else result = 0x80000000;
76 1.4 skrll
77 1.4 skrll if (Is_invalidtrap_enabled()) {
78 1.4 skrll return(INVALIDEXCEPTION);
79 1.4 skrll }
80 1.4 skrll Set_invalidflag();
81 1.4 skrll *dstptr = result;
82 1.4 skrll return(NOEXCEPTION);
83 1.1 fredette }
84 1.1 fredette }
85 1.1 fredette /*
86 1.1 fredette * Generate result
87 1.1 fredette */
88 1.1 fredette if (src_exponent >= 0) {
89 1.1 fredette temp = src;
90 1.1 fredette Sgl_clear_signexponent_set_hidden(temp);
91 1.1 fredette Int_from_sgl_mantissa(temp,src_exponent);
92 1.1 fredette if (Sgl_isone_sign(src)) result = -Sgl_all(temp);
93 1.1 fredette else result = Sgl_all(temp);
94 1.1 fredette *dstptr = result;
95 1.1 fredette
96 1.1 fredette /* check for inexact */
97 1.1 fredette if (Sgl_isinexact_to_fix(src,src_exponent)) {
98 1.1 fredette if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
99 1.1 fredette else Set_inexactflag();
100 1.1 fredette }
101 1.1 fredette }
102 1.1 fredette else {
103 1.1 fredette *dstptr = 0;
104 1.1 fredette
105 1.1 fredette /* check for inexact */
106 1.1 fredette if (Sgl_isnotzero_exponentmantissa(src)) {
107 1.1 fredette if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
108 1.1 fredette else Set_inexactflag();
109 1.1 fredette }
110 1.1 fredette }
111 1.1 fredette return(NOEXCEPTION);
112 1.1 fredette }
113 1.1 fredette
114 1.1 fredette /*
115 1.1 fredette * Single Floating-point to Double Fixed-point
116 1.1 fredette */
117 1.1 fredette /*ARGSUSED*/
118 1.1 fredette int
119 1.5 skrll sgl_to_dbl_fcnvfxt(sgl_floating_point *srcptr, dbl_integer *dstptr,
120 1.5 skrll unsigned int *status)
121 1.1 fredette {
122 1.1 fredette register int src_exponent, resultp1;
123 1.1 fredette register unsigned int src, temp, resultp2;
124 1.1 fredette
125 1.1 fredette src = *srcptr;
126 1.1 fredette src_exponent = Sgl_exponent(src) - SGL_BIAS;
127 1.1 fredette
128 1.1 fredette /*
129 1.1 fredette * Test for overflow
130 1.1 fredette */
131 1.1 fredette if (src_exponent > DBL_FX_MAX_EXP) {
132 1.1 fredette /* check for MININT */
133 1.1 fredette if ((src_exponent > DBL_FX_MAX_EXP + 1) ||
134 1.1 fredette Sgl_isnotzero_mantissa(src) || Sgl_iszero_sign(src)) {
135 1.4 skrll if (Sgl_iszero_sign(src)) {
136 1.4 skrll resultp1 = 0x7fffffff;
137 1.4 skrll resultp2 = 0xffffffff;
138 1.4 skrll }
139 1.4 skrll else {
140 1.4 skrll resultp1 = 0x80000000;
141 1.4 skrll resultp2 = 0;
142 1.4 skrll }
143 1.4 skrll
144 1.4 skrll if (Is_invalidtrap_enabled()) {
145 1.4 skrll return(INVALIDEXCEPTION);
146 1.4 skrll }
147 1.4 skrll Set_invalidflag();
148 1.4 skrll Dint_copytoptr(resultp1,resultp2,dstptr);
149 1.4 skrll return(NOEXCEPTION);
150 1.1 fredette }
151 1.1 fredette Dint_set_minint(resultp1,resultp2);
152 1.1 fredette Dint_copytoptr(resultp1,resultp2,dstptr);
153 1.1 fredette return(NOEXCEPTION);
154 1.1 fredette }
155 1.1 fredette /*
156 1.1 fredette * Generate result
157 1.1 fredette */
158 1.1 fredette if (src_exponent >= 0) {
159 1.1 fredette temp = src;
160 1.1 fredette Sgl_clear_signexponent_set_hidden(temp);
161 1.1 fredette Dint_from_sgl_mantissa(temp,src_exponent,resultp1,resultp2);
162 1.1 fredette if (Sgl_isone_sign(src)) {
163 1.1 fredette Dint_setone_sign(resultp1,resultp2);
164 1.1 fredette }
165 1.1 fredette Dint_copytoptr(resultp1,resultp2,dstptr);
166 1.1 fredette
167 1.1 fredette /* check for inexact */
168 1.1 fredette if (Sgl_isinexact_to_fix(src,src_exponent)) {
169 1.1 fredette if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
170 1.1 fredette else Set_inexactflag();
171 1.1 fredette }
172 1.1 fredette }
173 1.1 fredette else {
174 1.1 fredette Dint_setzero(resultp1,resultp2);
175 1.1 fredette Dint_copytoptr(resultp1,resultp2,dstptr);
176 1.1 fredette
177 1.1 fredette /* check for inexact */
178 1.1 fredette if (Sgl_isnotzero_exponentmantissa(src)) {
179 1.1 fredette if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
180 1.1 fredette else Set_inexactflag();
181 1.1 fredette }
182 1.1 fredette }
183 1.1 fredette return(NOEXCEPTION);
184 1.1 fredette }
185 1.1 fredette
186 1.1 fredette /*
187 1.1 fredette * Double Floating-point to Single Fixed-point
188 1.1 fredette */
189 1.1 fredette /*ARGSUSED*/
190 1.1 fredette int
191 1.5 skrll dbl_to_sgl_fcnvfxt(dbl_floating_point *srcptr, int *dstptr,
192 1.5 skrll unsigned int *status)
193 1.1 fredette {
194 1.1 fredette register unsigned int srcp1, srcp2, tempp1, tempp2;
195 1.1 fredette register int src_exponent, result;
196 1.1 fredette
197 1.1 fredette Dbl_copyfromptr(srcptr,srcp1,srcp2);
198 1.1 fredette src_exponent = Dbl_exponent(srcp1) - DBL_BIAS;
199 1.1 fredette
200 1.1 fredette /*
201 1.1 fredette * Test for overflow
202 1.1 fredette */
203 1.1 fredette if (src_exponent > SGL_FX_MAX_EXP) {
204 1.1 fredette /* check for MININT */
205 1.1 fredette if (Dbl_isoverflow_to_int(src_exponent,srcp1,srcp2)) {
206 1.4 skrll if (Dbl_iszero_sign(srcp1)) result = 0x7fffffff;
207 1.4 skrll else result = 0x80000000;
208 1.4 skrll
209 1.4 skrll if (Is_invalidtrap_enabled()) {
210 1.4 skrll return(INVALIDEXCEPTION);
211 1.4 skrll }
212 1.4 skrll Set_invalidflag();
213 1.4 skrll *dstptr = result;
214 1.4 skrll return(NOEXCEPTION);
215 1.1 fredette }
216 1.1 fredette }
217 1.1 fredette /*
218 1.1 fredette * Generate result
219 1.1 fredette */
220 1.1 fredette if (src_exponent >= 0) {
221 1.1 fredette tempp1 = srcp1;
222 1.1 fredette tempp2 = srcp2;
223 1.1 fredette Dbl_clear_signexponent_set_hidden(tempp1);
224 1.1 fredette Int_from_dbl_mantissa(tempp1,tempp2,src_exponent);
225 1.1 fredette if (Dbl_isone_sign(srcp1) && (src_exponent <= SGL_FX_MAX_EXP))
226 1.1 fredette result = -Dbl_allp1(tempp1);
227 1.1 fredette else result = Dbl_allp1(tempp1);
228 1.1 fredette *dstptr = result;
229 1.1 fredette
230 1.1 fredette /* check for inexact */
231 1.1 fredette if (Dbl_isinexact_to_fix(srcp1,srcp2,src_exponent)) {
232 1.1 fredette if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
233 1.1 fredette else Set_inexactflag();
234 1.1 fredette }
235 1.1 fredette }
236 1.1 fredette else {
237 1.1 fredette *dstptr = 0;
238 1.1 fredette
239 1.1 fredette /* check for inexact */
240 1.1 fredette if (Dbl_isnotzero_exponentmantissa(srcp1,srcp2)) {
241 1.1 fredette if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
242 1.1 fredette else Set_inexactflag();
243 1.1 fredette }
244 1.1 fredette }
245 1.1 fredette return(NOEXCEPTION);
246 1.1 fredette }
247 1.1 fredette
248 1.1 fredette /*
249 1.1 fredette * Double Floating-point to Double Fixed-point
250 1.1 fredette */
251 1.1 fredette /*ARGSUSED*/
252 1.1 fredette int
253 1.5 skrll dbl_to_dbl_fcnvfxt(dbl_floating_point *srcptr, dbl_integer *dstptr,
254 1.5 skrll unsigned int *status)
255 1.1 fredette {
256 1.1 fredette register int src_exponent, resultp1;
257 1.1 fredette register unsigned int srcp1, srcp2, tempp1, tempp2, resultp2;
258 1.1 fredette
259 1.1 fredette Dbl_copyfromptr(srcptr,srcp1,srcp2);
260 1.1 fredette src_exponent = Dbl_exponent(srcp1) - DBL_BIAS;
261 1.1 fredette
262 1.1 fredette /*
263 1.1 fredette * Test for overflow
264 1.1 fredette */
265 1.1 fredette if (src_exponent > DBL_FX_MAX_EXP) {
266 1.1 fredette /* check for MININT */
267 1.1 fredette if ((src_exponent > DBL_FX_MAX_EXP + 1) ||
268 1.1 fredette Dbl_isnotzero_mantissa(srcp1,srcp2) || Dbl_iszero_sign(srcp1)) {
269 1.4 skrll if (Dbl_iszero_sign(srcp1)) {
270 1.4 skrll resultp1 = 0x7fffffff;
271 1.4 skrll resultp2 = 0xffffffff;
272 1.4 skrll }
273 1.4 skrll else {
274 1.4 skrll resultp1 = 0x80000000;
275 1.4 skrll resultp2 = 0;
276 1.4 skrll }
277 1.4 skrll
278 1.4 skrll if (Is_invalidtrap_enabled()) {
279 1.4 skrll return(INVALIDEXCEPTION);
280 1.4 skrll }
281 1.4 skrll Set_invalidflag();
282 1.4 skrll Dint_copytoptr(resultp1,resultp2,dstptr);
283 1.4 skrll return(NOEXCEPTION);
284 1.1 fredette }
285 1.1 fredette }
286 1.1 fredette /*
287 1.1 fredette * Generate result
288 1.1 fredette */
289 1.1 fredette if (src_exponent >= 0) {
290 1.1 fredette tempp1 = srcp1;
291 1.1 fredette tempp2 = srcp2;
292 1.1 fredette Dbl_clear_signexponent_set_hidden(tempp1);
293 1.1 fredette Dint_from_dbl_mantissa(tempp1,tempp2,src_exponent,
294 1.1 fredette resultp1,resultp2);
295 1.1 fredette if (Dbl_isone_sign(srcp1)) {
296 1.1 fredette Dint_setone_sign(resultp1,resultp2);
297 1.1 fredette }
298 1.1 fredette Dint_copytoptr(resultp1,resultp2,dstptr);
299 1.1 fredette
300 1.1 fredette /* check for inexact */
301 1.1 fredette if (Dbl_isinexact_to_fix(srcp1,srcp2,src_exponent)) {
302 1.1 fredette if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
303 1.1 fredette else Set_inexactflag();
304 1.1 fredette }
305 1.1 fredette }
306 1.1 fredette else {
307 1.1 fredette Dint_setzero(resultp1,resultp2);
308 1.1 fredette Dint_copytoptr(resultp1,resultp2,dstptr);
309 1.1 fredette
310 1.1 fredette /* check for inexact */
311 1.1 fredette if (Dbl_isnotzero_exponentmantissa(srcp1,srcp2)) {
312 1.1 fredette if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
313 1.1 fredette else Set_inexactflag();
314 1.1 fredette }
315 1.1 fredette }
316 1.1 fredette return(NOEXCEPTION);
317 1.1 fredette }
318