fcnvfxt.c revision 1.4 1 1.4 skrll /* $NetBSD: fcnvfxt.c,v 1.4 2012/01/01 20:04:36 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 1.4 skrll __KERNEL_RCSID(0, "$NetBSD: fcnvfxt.c,v 1.4 2012/01/01 20:04:36 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 1.1 fredette sgl_to_sgl_fcnvfxt(srcptr,dstptr,status)
59 1.1 fredette
60 1.1 fredette sgl_floating_point *srcptr;
61 1.1 fredette int *dstptr;
62 1.1 fredette unsigned int *status;
63 1.1 fredette {
64 1.1 fredette register unsigned int src, temp;
65 1.1 fredette register int src_exponent, result;
66 1.1 fredette
67 1.1 fredette src = *srcptr;
68 1.1 fredette src_exponent = Sgl_exponent(src) - SGL_BIAS;
69 1.1 fredette
70 1.1 fredette /*
71 1.1 fredette * Test for overflow
72 1.1 fredette */
73 1.1 fredette if (src_exponent > SGL_FX_MAX_EXP) {
74 1.1 fredette /* check for MININT */
75 1.1 fredette if ((src_exponent > SGL_FX_MAX_EXP + 1) ||
76 1.1 fredette Sgl_isnotzero_mantissa(src) || Sgl_iszero_sign(src)) {
77 1.4 skrll if (Sgl_iszero_sign(src)) result = 0x7fffffff;
78 1.4 skrll else result = 0x80000000;
79 1.4 skrll
80 1.4 skrll if (Is_invalidtrap_enabled()) {
81 1.4 skrll return(INVALIDEXCEPTION);
82 1.4 skrll }
83 1.4 skrll Set_invalidflag();
84 1.4 skrll *dstptr = result;
85 1.4 skrll return(NOEXCEPTION);
86 1.1 fredette }
87 1.1 fredette }
88 1.1 fredette /*
89 1.1 fredette * Generate result
90 1.1 fredette */
91 1.1 fredette if (src_exponent >= 0) {
92 1.1 fredette temp = src;
93 1.1 fredette Sgl_clear_signexponent_set_hidden(temp);
94 1.1 fredette Int_from_sgl_mantissa(temp,src_exponent);
95 1.1 fredette if (Sgl_isone_sign(src)) result = -Sgl_all(temp);
96 1.1 fredette else result = Sgl_all(temp);
97 1.1 fredette *dstptr = result;
98 1.1 fredette
99 1.1 fredette /* check for inexact */
100 1.1 fredette if (Sgl_isinexact_to_fix(src,src_exponent)) {
101 1.1 fredette if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
102 1.1 fredette else Set_inexactflag();
103 1.1 fredette }
104 1.1 fredette }
105 1.1 fredette else {
106 1.1 fredette *dstptr = 0;
107 1.1 fredette
108 1.1 fredette /* check for inexact */
109 1.1 fredette if (Sgl_isnotzero_exponentmantissa(src)) {
110 1.1 fredette if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
111 1.1 fredette else Set_inexactflag();
112 1.1 fredette }
113 1.1 fredette }
114 1.1 fredette return(NOEXCEPTION);
115 1.1 fredette }
116 1.1 fredette
117 1.1 fredette /*
118 1.1 fredette * Single Floating-point to Double Fixed-point
119 1.1 fredette */
120 1.1 fredette /*ARGSUSED*/
121 1.1 fredette int
122 1.1 fredette sgl_to_dbl_fcnvfxt(srcptr,dstptr,status)
123 1.1 fredette
124 1.1 fredette sgl_floating_point *srcptr;
125 1.1 fredette dbl_integer *dstptr;
126 1.1 fredette unsigned int *status;
127 1.1 fredette {
128 1.1 fredette register int src_exponent, resultp1;
129 1.1 fredette register unsigned int src, temp, resultp2;
130 1.1 fredette
131 1.1 fredette src = *srcptr;
132 1.1 fredette src_exponent = Sgl_exponent(src) - SGL_BIAS;
133 1.1 fredette
134 1.1 fredette /*
135 1.1 fredette * Test for overflow
136 1.1 fredette */
137 1.1 fredette if (src_exponent > DBL_FX_MAX_EXP) {
138 1.1 fredette /* check for MININT */
139 1.1 fredette if ((src_exponent > DBL_FX_MAX_EXP + 1) ||
140 1.1 fredette Sgl_isnotzero_mantissa(src) || Sgl_iszero_sign(src)) {
141 1.4 skrll if (Sgl_iszero_sign(src)) {
142 1.4 skrll resultp1 = 0x7fffffff;
143 1.4 skrll resultp2 = 0xffffffff;
144 1.4 skrll }
145 1.4 skrll else {
146 1.4 skrll resultp1 = 0x80000000;
147 1.4 skrll resultp2 = 0;
148 1.4 skrll }
149 1.4 skrll
150 1.4 skrll if (Is_invalidtrap_enabled()) {
151 1.4 skrll return(INVALIDEXCEPTION);
152 1.4 skrll }
153 1.4 skrll Set_invalidflag();
154 1.4 skrll Dint_copytoptr(resultp1,resultp2,dstptr);
155 1.4 skrll return(NOEXCEPTION);
156 1.1 fredette }
157 1.1 fredette Dint_set_minint(resultp1,resultp2);
158 1.1 fredette Dint_copytoptr(resultp1,resultp2,dstptr);
159 1.1 fredette return(NOEXCEPTION);
160 1.1 fredette }
161 1.1 fredette /*
162 1.1 fredette * Generate result
163 1.1 fredette */
164 1.1 fredette if (src_exponent >= 0) {
165 1.1 fredette temp = src;
166 1.1 fredette Sgl_clear_signexponent_set_hidden(temp);
167 1.1 fredette Dint_from_sgl_mantissa(temp,src_exponent,resultp1,resultp2);
168 1.1 fredette if (Sgl_isone_sign(src)) {
169 1.1 fredette Dint_setone_sign(resultp1,resultp2);
170 1.1 fredette }
171 1.1 fredette Dint_copytoptr(resultp1,resultp2,dstptr);
172 1.1 fredette
173 1.1 fredette /* check for inexact */
174 1.1 fredette if (Sgl_isinexact_to_fix(src,src_exponent)) {
175 1.1 fredette if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
176 1.1 fredette else Set_inexactflag();
177 1.1 fredette }
178 1.1 fredette }
179 1.1 fredette else {
180 1.1 fredette Dint_setzero(resultp1,resultp2);
181 1.1 fredette Dint_copytoptr(resultp1,resultp2,dstptr);
182 1.1 fredette
183 1.1 fredette /* check for inexact */
184 1.1 fredette if (Sgl_isnotzero_exponentmantissa(src)) {
185 1.1 fredette if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
186 1.1 fredette else Set_inexactflag();
187 1.1 fredette }
188 1.1 fredette }
189 1.1 fredette return(NOEXCEPTION);
190 1.1 fredette }
191 1.1 fredette
192 1.1 fredette /*
193 1.1 fredette * Double Floating-point to Single Fixed-point
194 1.1 fredette */
195 1.1 fredette /*ARGSUSED*/
196 1.1 fredette int
197 1.1 fredette dbl_to_sgl_fcnvfxt(srcptr,dstptr,status)
198 1.1 fredette
199 1.1 fredette dbl_floating_point *srcptr;
200 1.1 fredette int *dstptr;
201 1.1 fredette unsigned int *status;
202 1.1 fredette {
203 1.1 fredette register unsigned int srcp1, srcp2, tempp1, tempp2;
204 1.1 fredette register int src_exponent, result;
205 1.1 fredette
206 1.1 fredette Dbl_copyfromptr(srcptr,srcp1,srcp2);
207 1.1 fredette src_exponent = Dbl_exponent(srcp1) - DBL_BIAS;
208 1.1 fredette
209 1.1 fredette /*
210 1.1 fredette * Test for overflow
211 1.1 fredette */
212 1.1 fredette if (src_exponent > SGL_FX_MAX_EXP) {
213 1.1 fredette /* check for MININT */
214 1.1 fredette if (Dbl_isoverflow_to_int(src_exponent,srcp1,srcp2)) {
215 1.4 skrll if (Dbl_iszero_sign(srcp1)) result = 0x7fffffff;
216 1.4 skrll else result = 0x80000000;
217 1.4 skrll
218 1.4 skrll if (Is_invalidtrap_enabled()) {
219 1.4 skrll return(INVALIDEXCEPTION);
220 1.4 skrll }
221 1.4 skrll Set_invalidflag();
222 1.4 skrll *dstptr = result;
223 1.4 skrll return(NOEXCEPTION);
224 1.1 fredette }
225 1.1 fredette }
226 1.1 fredette /*
227 1.1 fredette * Generate result
228 1.1 fredette */
229 1.1 fredette if (src_exponent >= 0) {
230 1.1 fredette tempp1 = srcp1;
231 1.1 fredette tempp2 = srcp2;
232 1.1 fredette Dbl_clear_signexponent_set_hidden(tempp1);
233 1.1 fredette Int_from_dbl_mantissa(tempp1,tempp2,src_exponent);
234 1.1 fredette if (Dbl_isone_sign(srcp1) && (src_exponent <= SGL_FX_MAX_EXP))
235 1.1 fredette result = -Dbl_allp1(tempp1);
236 1.1 fredette else result = Dbl_allp1(tempp1);
237 1.1 fredette *dstptr = result;
238 1.1 fredette
239 1.1 fredette /* check for inexact */
240 1.1 fredette if (Dbl_isinexact_to_fix(srcp1,srcp2,src_exponent)) {
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 else {
246 1.1 fredette *dstptr = 0;
247 1.1 fredette
248 1.1 fredette /* check for inexact */
249 1.1 fredette if (Dbl_isnotzero_exponentmantissa(srcp1,srcp2)) {
250 1.1 fredette if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
251 1.1 fredette else Set_inexactflag();
252 1.1 fredette }
253 1.1 fredette }
254 1.1 fredette return(NOEXCEPTION);
255 1.1 fredette }
256 1.1 fredette
257 1.1 fredette /*
258 1.1 fredette * Double Floating-point to Double Fixed-point
259 1.1 fredette */
260 1.1 fredette /*ARGSUSED*/
261 1.1 fredette int
262 1.1 fredette dbl_to_dbl_fcnvfxt(srcptr,dstptr,status)
263 1.1 fredette
264 1.1 fredette dbl_floating_point *srcptr;
265 1.1 fredette dbl_integer *dstptr;
266 1.1 fredette unsigned int *status;
267 1.1 fredette {
268 1.1 fredette register int src_exponent, resultp1;
269 1.1 fredette register unsigned int srcp1, srcp2, tempp1, tempp2, resultp2;
270 1.1 fredette
271 1.1 fredette Dbl_copyfromptr(srcptr,srcp1,srcp2);
272 1.1 fredette src_exponent = Dbl_exponent(srcp1) - DBL_BIAS;
273 1.1 fredette
274 1.1 fredette /*
275 1.1 fredette * Test for overflow
276 1.1 fredette */
277 1.1 fredette if (src_exponent > DBL_FX_MAX_EXP) {
278 1.1 fredette /* check for MININT */
279 1.1 fredette if ((src_exponent > DBL_FX_MAX_EXP + 1) ||
280 1.1 fredette Dbl_isnotzero_mantissa(srcp1,srcp2) || Dbl_iszero_sign(srcp1)) {
281 1.4 skrll if (Dbl_iszero_sign(srcp1)) {
282 1.4 skrll resultp1 = 0x7fffffff;
283 1.4 skrll resultp2 = 0xffffffff;
284 1.4 skrll }
285 1.4 skrll else {
286 1.4 skrll resultp1 = 0x80000000;
287 1.4 skrll resultp2 = 0;
288 1.4 skrll }
289 1.4 skrll
290 1.4 skrll if (Is_invalidtrap_enabled()) {
291 1.4 skrll return(INVALIDEXCEPTION);
292 1.4 skrll }
293 1.4 skrll Set_invalidflag();
294 1.4 skrll Dint_copytoptr(resultp1,resultp2,dstptr);
295 1.4 skrll return(NOEXCEPTION);
296 1.1 fredette }
297 1.1 fredette }
298 1.1 fredette /*
299 1.1 fredette * Generate result
300 1.1 fredette */
301 1.1 fredette if (src_exponent >= 0) {
302 1.1 fredette tempp1 = srcp1;
303 1.1 fredette tempp2 = srcp2;
304 1.1 fredette Dbl_clear_signexponent_set_hidden(tempp1);
305 1.1 fredette Dint_from_dbl_mantissa(tempp1,tempp2,src_exponent,
306 1.1 fredette resultp1,resultp2);
307 1.1 fredette if (Dbl_isone_sign(srcp1)) {
308 1.1 fredette Dint_setone_sign(resultp1,resultp2);
309 1.1 fredette }
310 1.1 fredette Dint_copytoptr(resultp1,resultp2,dstptr);
311 1.1 fredette
312 1.1 fredette /* check for inexact */
313 1.1 fredette if (Dbl_isinexact_to_fix(srcp1,srcp2,src_exponent)) {
314 1.1 fredette if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
315 1.1 fredette else Set_inexactflag();
316 1.1 fredette }
317 1.1 fredette }
318 1.1 fredette else {
319 1.1 fredette Dint_setzero(resultp1,resultp2);
320 1.1 fredette Dint_copytoptr(resultp1,resultp2,dstptr);
321 1.1 fredette
322 1.1 fredette /* check for inexact */
323 1.1 fredette if (Dbl_isnotzero_exponentmantissa(srcp1,srcp2)) {
324 1.1 fredette if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
325 1.1 fredette else Set_inexactflag();
326 1.1 fredette }
327 1.1 fredette }
328 1.1 fredette return(NOEXCEPTION);
329 1.1 fredette }
330