fcnvfx.c revision 1.5 1 1.1 fredette
2 1.5 skrll /* $OpenBSD: fcnvfx.c,v 1.8 2010/07/30 18:05:23 kettenis Exp $ */
3 1.1 fredette
4 1.1 fredette /*
5 1.1 fredette * Copyright 1996 1995 by Open Software Foundation, Inc.
6 1.1 fredette * All Rights Reserved
7 1.1 fredette *
8 1.1 fredette * Permission to use, copy, modify, and distribute this software and
9 1.1 fredette * its documentation for any purpose and without fee is hereby granted,
10 1.1 fredette * provided that the above copyright notice appears in all copies and
11 1.1 fredette * that both the copyright notice and this permission notice appear in
12 1.1 fredette * supporting documentation.
13 1.1 fredette *
14 1.1 fredette * OSF DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE
15 1.1 fredette * INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
16 1.1 fredette * FOR A PARTICULAR PURPOSE.
17 1.1 fredette *
18 1.1 fredette * IN NO EVENT SHALL OSF BE LIABLE FOR ANY SPECIAL, INDIRECT, OR
19 1.1 fredette * CONSEQUENTIAL DAMAGES OR ANY DAMAGES WHATSOEVER RESULTING FROM
20 1.1 fredette * LOSS OF USE, DATA OR PROFITS, WHETHER IN ACTION OF CONTRACT,
21 1.1 fredette * NEGLIGENCE, OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN CONNECTION
22 1.1 fredette * WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
23 1.1 fredette *
24 1.1 fredette */
25 1.1 fredette /*
26 1.1 fredette * pmk1.1
27 1.1 fredette */
28 1.1 fredette /*
29 1.1 fredette * (c) Copyright 1986 HEWLETT-PACKARD COMPANY
30 1.1 fredette *
31 1.1 fredette * To anyone who acknowledges that this file is provided "AS IS"
32 1.1 fredette * without any express or implied warranty:
33 1.1 fredette * permission to use, copy, modify, and distribute this file
34 1.1 fredette * for any purpose is hereby granted without fee, provided that
35 1.1 fredette * the above copyright notice and this notice appears in all
36 1.1 fredette * copies, and that the name of Hewlett-Packard Company not be
37 1.1 fredette * used in advertising or publicity pertaining to distribution
38 1.1 fredette * of the software without specific, written prior permission.
39 1.1 fredette * Hewlett-Packard Company makes no representations about the
40 1.1 fredette * suitability of this software for any purpose.
41 1.1 fredette */
42 1.2 lukem
43 1.2 lukem #include <sys/cdefs.h>
44 1.5 skrll __KERNEL_RCSID(0, "$NetBSD: fcnvfx.c,v 1.5 2012/01/01 20:04:36 skrll Exp $");
45 1.1 fredette
46 1.1 fredette #include "../spmath/float.h"
47 1.1 fredette #include "../spmath/sgl_float.h"
48 1.1 fredette #include "../spmath/dbl_float.h"
49 1.1 fredette #include "../spmath/cnv_float.h"
50 1.1 fredette
51 1.1 fredette /*
52 1.1 fredette * Single Floating-point to Single Fixed-point
53 1.1 fredette */
54 1.1 fredette /*ARGSUSED*/
55 1.1 fredette int
56 1.1 fredette sgl_to_sgl_fcnvfx(srcptr,dstptr,status)
57 1.1 fredette
58 1.1 fredette sgl_floating_point *srcptr;
59 1.1 fredette int *dstptr;
60 1.1 fredette unsigned int *status;
61 1.1 fredette {
62 1.1 fredette register unsigned int src, temp;
63 1.1 fredette register int src_exponent, result;
64 1.4 thorpej register int inexact = false;
65 1.1 fredette
66 1.1 fredette src = *srcptr;
67 1.1 fredette src_exponent = Sgl_exponent(src) - SGL_BIAS;
68 1.1 fredette
69 1.1 fredette /*
70 1.1 fredette * Test for overflow
71 1.1 fredette */
72 1.1 fredette if (src_exponent > SGL_FX_MAX_EXP) {
73 1.1 fredette /* check for MININT */
74 1.1 fredette if ((src_exponent > SGL_FX_MAX_EXP + 1) ||
75 1.1 fredette Sgl_isnotzero_mantissa(src) || Sgl_iszero_sign(src)) {
76 1.5 skrll if (Sgl_iszero_sign(src)) result = 0x7fffffff;
77 1.5 skrll else result = 0x80000000;
78 1.5 skrll
79 1.5 skrll if (Is_invalidtrap_enabled()) {
80 1.5 skrll return(INVALIDEXCEPTION);
81 1.5 skrll }
82 1.5 skrll Set_invalidflag();
83 1.5 skrll *dstptr = result;
84 1.5 skrll return(NOEXCEPTION);
85 1.1 fredette }
86 1.1 fredette }
87 1.1 fredette /*
88 1.1 fredette * Generate result
89 1.1 fredette */
90 1.1 fredette if (src_exponent >= 0) {
91 1.1 fredette temp = src;
92 1.1 fredette Sgl_clear_signexponent_set_hidden(temp);
93 1.1 fredette Int_from_sgl_mantissa(temp,src_exponent);
94 1.1 fredette if (Sgl_isone_sign(src)) result = -Sgl_all(temp);
95 1.1 fredette else result = Sgl_all(temp);
96 1.1 fredette
97 1.1 fredette /* check for inexact */
98 1.1 fredette if (Sgl_isinexact_to_fix(src,src_exponent)) {
99 1.4 thorpej inexact = true;
100 1.1 fredette /* round result */
101 1.1 fredette switch (Rounding_mode()) {
102 1.1 fredette case ROUNDPLUS:
103 1.1 fredette if (Sgl_iszero_sign(src)) result++;
104 1.1 fredette break;
105 1.1 fredette case ROUNDMINUS:
106 1.1 fredette if (Sgl_isone_sign(src)) result--;
107 1.1 fredette break;
108 1.1 fredette case ROUNDNEAREST:
109 1.1 fredette if (Sgl_isone_roundbit(src,src_exponent)) {
110 1.1 fredette if (Sgl_isone_stickybit(src,src_exponent)
111 1.1 fredette || (Sgl_isone_lowmantissa(temp))) {
112 1.1 fredette if (Sgl_iszero_sign(src)) result++;
113 1.1 fredette else result--;
114 1.1 fredette }
115 1.1 fredette }
116 1.1 fredette }
117 1.1 fredette }
118 1.1 fredette }
119 1.1 fredette else {
120 1.1 fredette result = 0;
121 1.1 fredette
122 1.1 fredette /* check for inexact */
123 1.1 fredette if (Sgl_isnotzero_exponentmantissa(src)) {
124 1.4 thorpej inexact = true;
125 1.1 fredette /* round result */
126 1.1 fredette switch (Rounding_mode()) {
127 1.1 fredette case ROUNDPLUS:
128 1.1 fredette if (Sgl_iszero_sign(src)) result++;
129 1.1 fredette break;
130 1.1 fredette case ROUNDMINUS:
131 1.1 fredette if (Sgl_isone_sign(src)) result--;
132 1.1 fredette break;
133 1.1 fredette case ROUNDNEAREST:
134 1.1 fredette if (src_exponent == -1)
135 1.1 fredette if (Sgl_isnotzero_mantissa(src)) {
136 1.1 fredette if (Sgl_iszero_sign(src)) result++;
137 1.1 fredette else result--;
138 1.1 fredette }
139 1.1 fredette }
140 1.1 fredette }
141 1.1 fredette }
142 1.1 fredette *dstptr = result;
143 1.1 fredette if (inexact) {
144 1.1 fredette if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
145 1.1 fredette else Set_inexactflag();
146 1.1 fredette }
147 1.1 fredette return(NOEXCEPTION);
148 1.1 fredette }
149 1.1 fredette
150 1.1 fredette /*
151 1.1 fredette * Single Floating-point to Double Fixed-point
152 1.1 fredette */
153 1.1 fredette /*ARGSUSED*/
154 1.1 fredette int
155 1.1 fredette sgl_to_dbl_fcnvfx(srcptr,dstptr,status)
156 1.1 fredette
157 1.1 fredette sgl_floating_point *srcptr;
158 1.1 fredette dbl_integer *dstptr;
159 1.1 fredette unsigned int *status;
160 1.1 fredette {
161 1.1 fredette register int src_exponent, resultp1;
162 1.1 fredette register unsigned int src, temp, resultp2;
163 1.4 thorpej register int inexact = false;
164 1.1 fredette
165 1.1 fredette src = *srcptr;
166 1.1 fredette src_exponent = Sgl_exponent(src) - SGL_BIAS;
167 1.1 fredette
168 1.1 fredette /*
169 1.1 fredette * Test for overflow
170 1.1 fredette */
171 1.1 fredette if (src_exponent > DBL_FX_MAX_EXP) {
172 1.1 fredette /* check for MININT */
173 1.1 fredette if ((src_exponent > DBL_FX_MAX_EXP + 1) ||
174 1.1 fredette Sgl_isnotzero_mantissa(src) || Sgl_iszero_sign(src)) {
175 1.5 skrll if (Sgl_iszero_sign(src)) {
176 1.5 skrll resultp1 = 0x7fffffff;
177 1.5 skrll resultp2 = 0xffffffff;
178 1.5 skrll }
179 1.5 skrll else {
180 1.5 skrll resultp1 = 0x80000000;
181 1.5 skrll resultp2 = 0;
182 1.5 skrll }
183 1.5 skrll
184 1.5 skrll if (Is_invalidtrap_enabled()) {
185 1.5 skrll return(INVALIDEXCEPTION);
186 1.5 skrll }
187 1.5 skrll Set_invalidflag();
188 1.5 skrll Dint_copytoptr(resultp1,resultp2,dstptr);
189 1.5 skrll return(NOEXCEPTION);
190 1.1 fredette }
191 1.1 fredette Dint_set_minint(resultp1,resultp2);
192 1.1 fredette Dint_copytoptr(resultp1,resultp2,dstptr);
193 1.1 fredette return(NOEXCEPTION);
194 1.1 fredette }
195 1.1 fredette /*
196 1.1 fredette * Generate result
197 1.1 fredette */
198 1.1 fredette if (src_exponent >= 0) {
199 1.1 fredette temp = src;
200 1.1 fredette Sgl_clear_signexponent_set_hidden(temp);
201 1.1 fredette Dint_from_sgl_mantissa(temp,src_exponent,resultp1,resultp2);
202 1.1 fredette if (Sgl_isone_sign(src)) {
203 1.1 fredette Dint_setone_sign(resultp1,resultp2);
204 1.1 fredette }
205 1.1 fredette
206 1.1 fredette /* check for inexact */
207 1.1 fredette if (Sgl_isinexact_to_fix(src,src_exponent)) {
208 1.4 thorpej inexact = true;
209 1.1 fredette /* round result */
210 1.1 fredette switch (Rounding_mode()) {
211 1.1 fredette case ROUNDPLUS:
212 1.1 fredette if (Sgl_iszero_sign(src)) {
213 1.1 fredette Dint_increment(resultp1,resultp2);
214 1.1 fredette }
215 1.1 fredette break;
216 1.1 fredette case ROUNDMINUS:
217 1.1 fredette if (Sgl_isone_sign(src)) {
218 1.1 fredette Dint_decrement(resultp1,resultp2);
219 1.1 fredette }
220 1.1 fredette break;
221 1.1 fredette case ROUNDNEAREST:
222 1.1 fredette if (Sgl_isone_roundbit(src,src_exponent))
223 1.1 fredette if (Sgl_isone_stickybit(src,src_exponent) ||
224 1.1 fredette (Dint_isone_lowp2(resultp2))) {
225 1.1 fredette if (Sgl_iszero_sign(src)) {
226 1.1 fredette Dint_increment(resultp1,resultp2);
227 1.1 fredette }
228 1.1 fredette else {
229 1.1 fredette Dint_decrement(resultp1,resultp2);
230 1.1 fredette }
231 1.1 fredette }
232 1.1 fredette }
233 1.1 fredette }
234 1.1 fredette }
235 1.1 fredette else {
236 1.1 fredette Dint_setzero(resultp1,resultp2);
237 1.1 fredette
238 1.1 fredette /* check for inexact */
239 1.1 fredette if (Sgl_isnotzero_exponentmantissa(src)) {
240 1.4 thorpej inexact = true;
241 1.1 fredette /* round result */
242 1.1 fredette switch (Rounding_mode()) {
243 1.1 fredette case ROUNDPLUS:
244 1.1 fredette if (Sgl_iszero_sign(src)) {
245 1.1 fredette Dint_increment(resultp1,resultp2);
246 1.1 fredette }
247 1.1 fredette break;
248 1.1 fredette case ROUNDMINUS:
249 1.1 fredette if (Sgl_isone_sign(src)) {
250 1.1 fredette Dint_decrement(resultp1,resultp2);
251 1.1 fredette }
252 1.1 fredette break;
253 1.1 fredette case ROUNDNEAREST:
254 1.1 fredette if (src_exponent == -1)
255 1.1 fredette if (Sgl_isnotzero_mantissa(src)) {
256 1.1 fredette if (Sgl_iszero_sign(src)) {
257 1.1 fredette Dint_increment(resultp1,resultp2);
258 1.1 fredette }
259 1.1 fredette else {
260 1.1 fredette Dint_decrement(resultp1,resultp2);
261 1.1 fredette }
262 1.1 fredette }
263 1.1 fredette }
264 1.1 fredette }
265 1.1 fredette }
266 1.1 fredette Dint_copytoptr(resultp1,resultp2,dstptr);
267 1.1 fredette if (inexact) {
268 1.1 fredette if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
269 1.1 fredette else Set_inexactflag();
270 1.1 fredette }
271 1.1 fredette return(NOEXCEPTION);
272 1.1 fredette }
273 1.1 fredette
274 1.1 fredette /*
275 1.1 fredette * Double Floating-point to Single Fixed-point
276 1.1 fredette */
277 1.1 fredette /*ARGSUSED*/
278 1.1 fredette int
279 1.1 fredette dbl_to_sgl_fcnvfx(srcptr,dstptr,status)
280 1.1 fredette
281 1.1 fredette dbl_floating_point *srcptr;
282 1.1 fredette int *dstptr;
283 1.1 fredette unsigned int *status;
284 1.1 fredette {
285 1.1 fredette register unsigned int srcp1,srcp2, tempp1,tempp2;
286 1.1 fredette register int src_exponent, result;
287 1.4 thorpej register int inexact = false;
288 1.1 fredette
289 1.1 fredette Dbl_copyfromptr(srcptr,srcp1,srcp2);
290 1.1 fredette src_exponent = Dbl_exponent(srcp1) - DBL_BIAS;
291 1.1 fredette
292 1.1 fredette /*
293 1.1 fredette * Test for overflow
294 1.1 fredette */
295 1.1 fredette if (src_exponent > SGL_FX_MAX_EXP) {
296 1.1 fredette /* check for MININT */
297 1.1 fredette if (Dbl_isoverflow_to_int(src_exponent,srcp1,srcp2)) {
298 1.5 skrll if (Dbl_iszero_sign(srcp1)) result = 0x7fffffff;
299 1.5 skrll else result = 0x80000000;
300 1.5 skrll
301 1.5 skrll if (Is_invalidtrap_enabled()) {
302 1.5 skrll return(INVALIDEXCEPTION);
303 1.5 skrll }
304 1.5 skrll Set_invalidflag();
305 1.5 skrll *dstptr = result;
306 1.5 skrll return(NOEXCEPTION);
307 1.1 fredette }
308 1.1 fredette }
309 1.1 fredette /*
310 1.1 fredette * Generate result
311 1.1 fredette */
312 1.1 fredette if (src_exponent >= 0) {
313 1.1 fredette tempp1 = srcp1;
314 1.1 fredette tempp2 = srcp2;
315 1.1 fredette Dbl_clear_signexponent_set_hidden(tempp1);
316 1.1 fredette Int_from_dbl_mantissa(tempp1,tempp2,src_exponent);
317 1.1 fredette if (Dbl_isone_sign(srcp1) && (src_exponent <= SGL_FX_MAX_EXP))
318 1.1 fredette result = -Dbl_allp1(tempp1);
319 1.1 fredette else result = Dbl_allp1(tempp1);
320 1.1 fredette
321 1.1 fredette /* check for inexact */
322 1.1 fredette if (Dbl_isinexact_to_fix(srcp1,srcp2,src_exponent)) {
323 1.4 thorpej inexact = true;
324 1.1 fredette /* round result */
325 1.1 fredette switch (Rounding_mode()) {
326 1.1 fredette case ROUNDPLUS:
327 1.5 skrll if (Dbl_iszero_sign(srcp1))
328 1.5 skrll result++;
329 1.1 fredette break;
330 1.1 fredette case ROUNDMINUS:
331 1.1 fredette if (Dbl_isone_sign(srcp1)) result--;
332 1.1 fredette break;
333 1.1 fredette case ROUNDNEAREST:
334 1.1 fredette if (Dbl_isone_roundbit(srcp1,srcp2,src_exponent))
335 1.1 fredette if (Dbl_isone_stickybit(srcp1,srcp2,src_exponent) ||
336 1.1 fredette (Dbl_isone_lowmantissap1(tempp1))) {
337 1.1 fredette if (Dbl_iszero_sign(srcp1)) result++;
338 1.1 fredette else result--;
339 1.1 fredette }
340 1.1 fredette }
341 1.1 fredette /* check for overflow */
342 1.1 fredette if ((Dbl_iszero_sign(srcp1) && result < 0) ||
343 1.1 fredette (Dbl_isone_sign(srcp1) && result > 0)) {
344 1.5 skrll
345 1.5 skrll if (Dbl_iszero_sign(srcp1))
346 1.5 skrll result = 0x7fffffff;
347 1.5 skrll else
348 1.5 skrll result = 0x80000000;
349 1.5 skrll
350 1.5 skrll if (Is_overflowtrap_enabled()) {
351 1.5 skrll if (Is_inexacttrap_enabled())
352 1.5 skrll return(OVERFLOWEXCEPTION|INEXACTEXCEPTION);
353 1.5 skrll else Set_inexactflag();
354 1.5 skrll return(OVERFLOWEXCEPTION);
355 1.5 skrll }
356 1.5 skrll Set_overflowflag();
357 1.5 skrll *dstptr = result;
358 1.5 skrll if (Is_inexacttrap_enabled() )
359 1.5 skrll return(INEXACTEXCEPTION);
360 1.5 skrll else Set_inexactflag();
361 1.5 skrll return(NOEXCEPTION);
362 1.1 fredette }
363 1.1 fredette }
364 1.1 fredette }
365 1.1 fredette else {
366 1.1 fredette result = 0;
367 1.1 fredette
368 1.1 fredette /* check for inexact */
369 1.1 fredette if (Dbl_isnotzero_exponentmantissa(srcp1,srcp2)) {
370 1.4 thorpej inexact = true;
371 1.1 fredette /* round result */
372 1.1 fredette switch (Rounding_mode()) {
373 1.1 fredette case ROUNDPLUS:
374 1.1 fredette if (Dbl_iszero_sign(srcp1)) result++;
375 1.1 fredette break;
376 1.1 fredette case ROUNDMINUS:
377 1.1 fredette if (Dbl_isone_sign(srcp1)) result--;
378 1.1 fredette break;
379 1.1 fredette case ROUNDNEAREST:
380 1.1 fredette if (src_exponent == -1)
381 1.1 fredette if (Dbl_isnotzero_mantissa(srcp1,srcp2)) {
382 1.1 fredette if (Dbl_iszero_sign(srcp1)) result++;
383 1.1 fredette else result--;
384 1.1 fredette }
385 1.1 fredette }
386 1.1 fredette }
387 1.1 fredette }
388 1.1 fredette *dstptr = result;
389 1.1 fredette if (inexact) {
390 1.1 fredette if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
391 1.1 fredette else Set_inexactflag();
392 1.1 fredette }
393 1.1 fredette return(NOEXCEPTION);
394 1.1 fredette }
395 1.1 fredette
396 1.1 fredette /*
397 1.1 fredette * Double Floating-point to Double Fixed-point
398 1.1 fredette */
399 1.1 fredette /*ARGSUSED*/
400 1.1 fredette int
401 1.1 fredette dbl_to_dbl_fcnvfx(srcptr,dstptr,status)
402 1.1 fredette
403 1.1 fredette dbl_floating_point *srcptr;
404 1.1 fredette dbl_integer *dstptr;
405 1.1 fredette unsigned int *status;
406 1.1 fredette {
407 1.1 fredette register int src_exponent, resultp1;
408 1.1 fredette register unsigned int srcp1, srcp2, tempp1, tempp2, resultp2;
409 1.4 thorpej register int inexact = false;
410 1.1 fredette
411 1.1 fredette Dbl_copyfromptr(srcptr,srcp1,srcp2);
412 1.1 fredette src_exponent = Dbl_exponent(srcp1) - DBL_BIAS;
413 1.1 fredette
414 1.1 fredette /*
415 1.1 fredette * Test for overflow
416 1.1 fredette */
417 1.1 fredette if (src_exponent > DBL_FX_MAX_EXP) {
418 1.1 fredette /* check for MININT */
419 1.1 fredette if ((src_exponent > DBL_FX_MAX_EXP + 1) ||
420 1.1 fredette Dbl_isnotzero_mantissa(srcp1,srcp2) || Dbl_iszero_sign(srcp1)) {
421 1.5 skrll if (Dbl_iszero_sign(srcp1)) {
422 1.5 skrll resultp1 = 0x7fffffff;
423 1.5 skrll resultp2 = 0xffffffff;
424 1.5 skrll }
425 1.5 skrll else {
426 1.5 skrll resultp1 = 0x80000000;
427 1.5 skrll resultp2 = 0;
428 1.5 skrll }
429 1.5 skrll
430 1.5 skrll if (Is_invalidtrap_enabled()) {
431 1.5 skrll return(INVALIDEXCEPTION);
432 1.5 skrll }
433 1.5 skrll Set_invalidflag();
434 1.5 skrll Dint_copytoptr(resultp1,resultp2,dstptr);
435 1.5 skrll return(NOEXCEPTION);
436 1.1 fredette }
437 1.1 fredette }
438 1.1 fredette
439 1.1 fredette /*
440 1.1 fredette * Generate result
441 1.1 fredette */
442 1.1 fredette if (src_exponent >= 0) {
443 1.1 fredette tempp1 = srcp1;
444 1.1 fredette tempp2 = srcp2;
445 1.1 fredette Dbl_clear_signexponent_set_hidden(tempp1);
446 1.1 fredette Dint_from_dbl_mantissa(tempp1,tempp2,src_exponent,
447 1.1 fredette resultp1, resultp2);
448 1.1 fredette if (Dbl_isone_sign(srcp1)) {
449 1.1 fredette Dint_setone_sign(resultp1,resultp2);
450 1.1 fredette }
451 1.1 fredette
452 1.1 fredette /* check for inexact */
453 1.1 fredette if (Dbl_isinexact_to_fix(srcp1,srcp2,src_exponent)) {
454 1.4 thorpej inexact = true;
455 1.1 fredette /* round result */
456 1.1 fredette switch (Rounding_mode()) {
457 1.1 fredette case ROUNDPLUS:
458 1.1 fredette if (Dbl_iszero_sign(srcp1)) {
459 1.1 fredette Dint_increment(resultp1,resultp2);
460 1.1 fredette }
461 1.1 fredette break;
462 1.1 fredette case ROUNDMINUS:
463 1.1 fredette if (Dbl_isone_sign(srcp1)) {
464 1.1 fredette Dint_decrement(resultp1,resultp2);
465 1.1 fredette }
466 1.1 fredette break;
467 1.1 fredette case ROUNDNEAREST:
468 1.1 fredette if (Dbl_isone_roundbit(srcp1,srcp2,src_exponent))
469 1.1 fredette if (Dbl_isone_stickybit(srcp1,srcp2,src_exponent) ||
470 1.1 fredette (Dint_isone_lowp2(resultp2))) {
471 1.1 fredette if (Dbl_iszero_sign(srcp1)) {
472 1.1 fredette Dint_increment(resultp1,resultp2);
473 1.1 fredette }
474 1.1 fredette else {
475 1.1 fredette Dint_decrement(resultp1,resultp2);
476 1.1 fredette }
477 1.1 fredette }
478 1.1 fredette }
479 1.1 fredette }
480 1.1 fredette }
481 1.1 fredette else {
482 1.1 fredette Dint_setzero(resultp1,resultp2);
483 1.1 fredette
484 1.1 fredette /* check for inexact */
485 1.1 fredette if (Dbl_isnotzero_exponentmantissa(srcp1,srcp2)) {
486 1.4 thorpej inexact = true;
487 1.1 fredette /* round result */
488 1.1 fredette switch (Rounding_mode()) {
489 1.1 fredette case ROUNDPLUS:
490 1.1 fredette if (Dbl_iszero_sign(srcp1)) {
491 1.1 fredette Dint_increment(resultp1,resultp2);
492 1.1 fredette }
493 1.1 fredette break;
494 1.1 fredette case ROUNDMINUS:
495 1.1 fredette if (Dbl_isone_sign(srcp1)) {
496 1.1 fredette Dint_decrement(resultp1,resultp2);
497 1.1 fredette }
498 1.1 fredette break;
499 1.1 fredette case ROUNDNEAREST:
500 1.1 fredette if (src_exponent == -1)
501 1.1 fredette if (Dbl_isnotzero_mantissa(srcp1,srcp2)) {
502 1.1 fredette if (Dbl_iszero_sign(srcp1)) {
503 1.1 fredette Dint_increment(resultp1,resultp2);
504 1.1 fredette }
505 1.1 fredette else {
506 1.1 fredette Dint_decrement(resultp1,resultp2);
507 1.1 fredette }
508 1.1 fredette }
509 1.1 fredette }
510 1.1 fredette }
511 1.1 fredette }
512 1.1 fredette Dint_copytoptr(resultp1,resultp2,dstptr);
513 1.1 fredette if (inexact) {
514 1.1 fredette if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
515 1.1 fredette else Set_inexactflag();
516 1.1 fredette }
517 1.1 fredette return(NOEXCEPTION);
518 1.1 fredette }
519