1 // SPDX-License-Identifier: GPL-2.0-or-later
2 /*
3 * Linux/PA-RISC Project (http://www.parisc-linux.org/)
4 *
5 * Floating-point emulation code
6 * Copyright (C) 2001 Hewlett-Packard (Paul Bame) <bame@debian.org>
7 */
8 /*
9 * BEGIN_DESC
10 *
11 * File:
12 * @(#) pa/spmath/fcnvfxt.c $Revision: 1.1 $
13 *
14 * Purpose:
15 * Single Floating-point to Single Fixed-point /w truncated result
16 * Single Floating-point to Double Fixed-point /w truncated result
17 * Double Floating-point to Single Fixed-point /w truncated result
18 * Double Floating-point to Double Fixed-point /w truncated result
19 *
20 * External Interfaces:
21 * dbl_to_dbl_fcnvfxt(srcptr,_nullptr,dstptr,status)
22 * dbl_to_sgl_fcnvfxt(srcptr,_nullptr,dstptr,status)
23 * sgl_to_dbl_fcnvfxt(srcptr,_nullptr,dstptr,status)
24 * sgl_to_sgl_fcnvfxt(srcptr,_nullptr,dstptr,status)
25 *
26 * Internal Interfaces:
27 *
28 * Theory:
29 * <<please update with a overview of the operation of this file>>
30 *
31 * END_DESC
32 */
33
34
35 #include "float.h"
36 #include "sgl_float.h"
37 #include "dbl_float.h"
38 #include "cnv_float.h"
39
40 /*
41 * Convert single floating-point to single fixed-point format
42 * with truncated result
43 */
44 /*ARGSUSED*/
45 int
46 sgl_to_sgl_fcnvfxt(
47 sgl_floating_point *srcptr,
48 unsigned int *_nullptr,
49 int *dstptr,
50 unsigned int *status)
51 {
52 register unsigned int src, temp;
53 register int src_exponent, result;
54
55 src = *srcptr;
56 src_exponent = Sgl_exponent(src) - SGL_BIAS;
57
58 /*
59 * Test for overflow
60 */
61 if (src_exponent > SGL_FX_MAX_EXP) {
62 /* check for MININT */
63 if ((src_exponent > SGL_FX_MAX_EXP + 1) ||
64 Sgl_isnotzero_mantissa(src) || Sgl_iszero_sign(src)) {
65 if (Sgl_iszero_sign(src)) result = 0x7fffffff;
66 else result = 0x80000000;
67
68 if (Is_invalidtrap_enabled()) {
69 return(INVALIDEXCEPTION);
70 }
71 Set_invalidflag();
72 *dstptr = result;
73 return(NOEXCEPTION);
74 }
75 }
76 /*
77 * Generate result
78 */
79 if (src_exponent >= 0) {
80 temp = src;
81 Sgl_clear_signexponent_set_hidden(temp);
82 Int_from_sgl_mantissa(temp,src_exponent);
83 if (Sgl_isone_sign(src)) result = -Sgl_all(temp);
84 else result = Sgl_all(temp);
85 *dstptr = result;
86
87 /* check for inexact */
88 if (Sgl_isinexact_to_fix(src,src_exponent)) {
89 if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
90 else Set_inexactflag();
91 }
92 }
93 else {
94 *dstptr = 0;
95
96 /* check for inexact */
97 if (Sgl_isnotzero_exponentmantissa(src)) {
98 if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
99 else Set_inexactflag();
100 }
101 }
102 return(NOEXCEPTION);
103 }
104
105 /*
106 * Single Floating-point to Double Fixed-point
107 */
108 /*ARGSUSED*/
109 int
110 sgl_to_dbl_fcnvfxt(
111 sgl_floating_point *srcptr,
112 unsigned int *_nullptr,
113 dbl_integer *dstptr,
114 unsigned int *status)
115 {
116 register int src_exponent, resultp1;
117 register unsigned int src, temp, resultp2;
118
119 src = *srcptr;
120 src_exponent = Sgl_exponent(src) - SGL_BIAS;
121
122 /*
123 * Test for overflow
124 */
125 if (src_exponent > DBL_FX_MAX_EXP) {
126 /* check for MININT */
127 if ((src_exponent > DBL_FX_MAX_EXP + 1) ||
128 Sgl_isnotzero_mantissa(src) || Sgl_iszero_sign(src)) {
129 if (Sgl_iszero_sign(src)) {
130 resultp1 = 0x7fffffff;
131 resultp2 = 0xffffffff;
132 }
133 else {
134 resultp1 = 0x80000000;
135 resultp2 = 0;
136 }
137 if (Is_invalidtrap_enabled()) {
138 return(INVALIDEXCEPTION);
139 }
140 Set_invalidflag();
141 Dint_copytoptr(resultp1,resultp2,dstptr);
142 return(NOEXCEPTION);
143 }
144 Dint_set_minint(resultp1,resultp2);
145 Dint_copytoptr(resultp1,resultp2,dstptr);
146 return(NOEXCEPTION);
147 }
148 /*
149 * Generate result
150 */
151 if (src_exponent >= 0) {
152 temp = src;
153 Sgl_clear_signexponent_set_hidden(temp);
154 Dint_from_sgl_mantissa(temp,src_exponent,resultp1,resultp2);
155 if (Sgl_isone_sign(src)) {
156 Dint_setone_sign(resultp1,resultp2);
157 }
158 Dint_copytoptr(resultp1,resultp2,dstptr);
159
160 /* check for inexact */
161 if (Sgl_isinexact_to_fix(src,src_exponent)) {
162 if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
163 else Set_inexactflag();
164 }
165 }
166 else {
167 Dint_setzero(resultp1,resultp2);
168 Dint_copytoptr(resultp1,resultp2,dstptr);
169
170 /* check for inexact */
171 if (Sgl_isnotzero_exponentmantissa(src)) {
172 if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
173 else Set_inexactflag();
174 }
175 }
176 return(NOEXCEPTION);
177 }
178
179 /*
180 * Double Floating-point to Single Fixed-point
181 */
182 /*ARGSUSED*/
183 int
184 dbl_to_sgl_fcnvfxt(
185 dbl_floating_point *srcptr,
186 unsigned int *_nullptr,
187 int *dstptr,
188 unsigned int *status)
189 {
190 register unsigned int srcp1, srcp2, tempp1, tempp2;
191 register int src_exponent, result;
192
193 Dbl_copyfromptr(srcptr,srcp1,srcp2);
194 src_exponent = Dbl_exponent(srcp1) - DBL_BIAS;
195
196 /*
197 * Test for overflow
198 */
199 if (src_exponent > SGL_FX_MAX_EXP) {
200 /* check for MININT */
201 if (Dbl_isoverflow_to_int(src_exponent,srcp1,srcp2)) {
202 if (Dbl_iszero_sign(srcp1)) result = 0x7fffffff;
203 else result = 0x80000000;
204
205 if (Is_invalidtrap_enabled()) {
206 return(INVALIDEXCEPTION);
207 }
208 Set_invalidflag();
209 *dstptr = result;
210 return(NOEXCEPTION);
211 }
212 }
213 /*
214 * Generate result
215 */
216 if (src_exponent >= 0) {
217 tempp1 = srcp1;
218 tempp2 = srcp2;
219 Dbl_clear_signexponent_set_hidden(tempp1);
220 Int_from_dbl_mantissa(tempp1,tempp2,src_exponent);
221 if (Dbl_isone_sign(srcp1) && (src_exponent <= SGL_FX_MAX_EXP))
222 result = -Dbl_allp1(tempp1);
223 else result = Dbl_allp1(tempp1);
224 *dstptr = result;
225
226 /* check for inexact */
227 if (Dbl_isinexact_to_fix(srcp1,srcp2,src_exponent)) {
228 if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
229 else Set_inexactflag();
230 }
231 }
232 else {
233 *dstptr = 0;
234
235 /* check for inexact */
236 if (Dbl_isnotzero_exponentmantissa(srcp1,srcp2)) {
237 if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
238 else Set_inexactflag();
239 }
240 }
241 return(NOEXCEPTION);
242 }
243
244 /*
245 * Double Floating-point to Double Fixed-point
246 */
247 /*ARGSUSED*/
248 int
249 dbl_to_dbl_fcnvfxt(
250 dbl_floating_point *srcptr,
251 unsigned int *_nullptr,
252 dbl_integer *dstptr,
253 unsigned int *status)
254 {
255 register int src_exponent, resultp1;
256 register unsigned int srcp1, srcp2, tempp1, tempp2, resultp2;
257
258 Dbl_copyfromptr(srcptr,srcp1,srcp2);
259 src_exponent = Dbl_exponent(srcp1) - DBL_BIAS;
260
261 /*
262 * Test for overflow
263 */
264 if (src_exponent > DBL_FX_MAX_EXP) {
265 /* check for MININT */
266 if ((src_exponent > DBL_FX_MAX_EXP + 1) ||
267 Dbl_isnotzero_mantissa(srcp1,srcp2) || Dbl_iszero_sign(srcp1)) {
268 if (Dbl_iszero_sign(srcp1)) {
269 resultp1 = 0x7fffffff;
270 resultp2 = 0xffffffff;
271 }
272 else {
273 resultp1 = 0x80000000;
274 resultp2 = 0;
275 }
276 if (Is_invalidtrap_enabled()) {
277 return(INVALIDEXCEPTION);
278 }
279 Set_invalidflag();
280 Dint_copytoptr(resultp1,resultp2,dstptr);
281 return(NOEXCEPTION);
282 }
283 }
284 /*
285 * Generate result
286 */
287 if (src_exponent >= 0) {
288 tempp1 = srcp1;
289 tempp2 = srcp2;
290 Dbl_clear_signexponent_set_hidden(tempp1);
291 Dint_from_dbl_mantissa(tempp1,tempp2,src_exponent,
292 resultp1,resultp2);
293 if (Dbl_isone_sign(srcp1)) {
294 Dint_setone_sign(resultp1,resultp2);
295 }
296 Dint_copytoptr(resultp1,resultp2,dstptr);
297
298 /* check for inexact */
299 if (Dbl_isinexact_to_fix(srcp1,srcp2,src_exponent)) {
300 if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
301 else Set_inexactflag();
302 }
303 }
304 else {
305 Dint_setzero(resultp1,resultp2);
306 Dint_copytoptr(resultp1,resultp2,dstptr);
307
308 /* check for inexact */
309 if (Dbl_isnotzero_exponentmantissa(srcp1,srcp2)) {
310 if (Is_inexacttrap_enabled()) return(INEXACTEXCEPTION);
311 else Set_inexactflag();
312 }
313 }
314 return(NOEXCEPTION);
315 }
316
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