xref: /illumos-gate/usr/src/uts/sparc/fpu/unpack.c (revision f3041bfa)
1 /*
2  * CDDL HEADER START
3  *
4  * The contents of this file are subject to the terms of the
5  * Common Development and Distribution License, Version 1.0 only
6  * (the "License").  You may not use this file except in compliance
7  * with the License.
8  *
9  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10  * or http://www.opensolaris.org/os/licensing.
11  * See the License for the specific language governing permissions
12  * and limitations under the License.
13  *
14  * When distributing Covered Code, include this CDDL HEADER in each
15  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16  * If applicable, add the following below this CDDL HEADER, with the
17  * fields enclosed by brackets "[]" replaced with your own identifying
18  * information: Portions Copyright [yyyy] [name of copyright owner]
19  *
20  * CDDL HEADER END
21  */
22 /*
23  * Copyright 1987, 2000, 2003 Sun Microsystems, Inc.  All rights reserved.
24  * Use is subject to license terms.
25  */
26 
27 #pragma ident	"%Z%%M%	%I%	%E% SMI"	/* SunOS-4.1 */
28 
29 /* Unpack procedures for Sparc FPU simulator. */
30 
31 #include <sys/fpu/fpu_simulator.h>
32 #include <sys/fpu/globals.h>
33 
34 static void
35 unpackint32(
36 	unpacked	*pu,	/* unpacked result */
37 	int32_t		x)	/* packed int32_t */
38 {
39 	uint_t ux;
40 
41 	pu->sticky = pu->rounded = 0;
42 	if (x == 0) {
43 		pu->sign = 0;
44 		pu->fpclass = fp_zero;
45 	} else {
46 		(*pu).sign = x < 0;
47 		(*pu).fpclass = fp_normal;
48 		(*pu).exponent = INTEGER_BIAS;
49 		if (x < 0) ux = -x; else ux = x;
50 		(*pu).significand[0] = ux>>15;
51 		(*pu).significand[1] = (ux&0x7fff)<<17;
52 		(*pu).significand[2] = 0;
53 		(*pu).significand[3] = 0;
54 		fpu_normalize(pu);
55 	}
56 }
57 
58 
59 /*
60  * Workaround for bug 4287443--- we have to convince the compiler
61  * that unpackint64 isn't a leaf routine.
62  */
63 static void
64 subroutine(void)
65 {
66 }
67 
68 static void
69 unpackint64(
70 	unpacked	*pu,	/* unpacked result */
71 	int64_t		x)	/* packed int64_t */
72 {
73 	union {
74 		uint64_t ll;
75 		uint32_t i[2];
76 	} ux;
77 
78 	subroutine();
79 
80 	pu->sticky = pu->rounded = 0;
81 	if (x == 0) {
82 		pu->sign = 0;
83 		pu->fpclass = fp_zero;
84 	} else {
85 		(*pu).sign = x < 0;
86 		(*pu).fpclass = fp_normal;
87 		(*pu).exponent = LONGLONG_BIAS;
88 		if (x < 0) ux.ll = -x; else ux.ll = x;
89 		(*pu).significand[0] = ux.i[0]>>15;
90 		(*pu).significand[1] = (((ux.i[0]&0x7fff)<<17) | (ux.i[1]>>15));
91 		(*pu).significand[2] = (ux.i[1]&0x7fff)<<17;
92 		(*pu).significand[3] = 0;
93 		fpu_normalize(pu);
94 	}
95 }
96 
97 void
98 unpacksingle(
99 	fp_simd_type	*pfpsd,	/* simulator data */
100 	unpacked	*pu,	/* unpacked result */
101 	single_type	x)	/* packed single */
102 {
103 	uint_t U;
104 
105 	pu->sticky = pu->rounded = 0;
106 	U = x.significand;
107 	(*pu).sign = x.sign;
108 	pu->significand[1] = 0;
109 	pu->significand[2] = 0;
110 	pu->significand[3] = 0;
111 	if (x.exponent == 0) {				/* zero or sub */
112 		if (x.significand == 0) {		/* zero */
113 			pu->fpclass = fp_zero;
114 			return;
115 		} else {				/* subnormal */
116 			pu->fpclass = fp_normal;
117 			pu->exponent = -SINGLE_BIAS-6;
118 			pu->significand[0] = U;
119 			fpu_normalize(pu);
120 			return;
121 		}
122 	} else if (x.exponent == 0xff) {		/* inf or nan */
123 		if (x.significand == 0) {		/* inf */
124 			pu->fpclass = fp_infinity;
125 			return;
126 		} else {				/* nan */
127 			if ((U & 0x400000) != 0) {	/* quiet */
128 				pu->fpclass = fp_quiet;
129 			} else {			/* signaling */
130 				pu->fpclass = fp_signaling;
131 				fpu_set_exception(pfpsd, fp_invalid);
132 			}
133 			pu->significand[0] = 0x18000 | (U >> 7);
134 			(*pu).significand[1] = ((U&0x7f)<<25);
135 			return;
136 		}
137 	}
138 	(*pu).exponent = x.exponent - SINGLE_BIAS;
139 	(*pu).fpclass = fp_normal;
140 	(*pu).significand[0] = 0x10000|(U>>7);
141 	(*pu).significand[1] = ((U&0x7f)<<25);
142 }
143 
144 void
145 unpackdouble(
146 	fp_simd_type	*pfpsd,	/* simulator data */
147 	unpacked	*pu,	/* unpacked result */
148 	double_type	x,	/* packed double, sign/exponent/upper 20 bits */
149 	uint_t		y)	/* and the lower 32 bits of the significand */
150 {
151 	uint_t U;
152 
153 	pu->sticky = pu->rounded = 0;
154 	U = x.significand;
155 	(*pu).sign = x.sign;
156 	pu->significand[1] = y;
157 	pu->significand[2] = 0;
158 	pu->significand[3] = 0;
159 	if (x.exponent == 0) {				/* zero or sub */
160 		if ((x.significand == 0) && (y == 0)) {	/* zero */
161 			pu->fpclass = fp_zero;
162 			return;
163 		} else {				/* subnormal */
164 			pu->fpclass = fp_normal;
165 			pu->exponent = -DOUBLE_BIAS-3;
166 			pu->significand[0] = U;
167 			fpu_normalize(pu);
168 			return;
169 		}
170 	} else if (x.exponent == 0x7ff) {		/* inf or nan */
171 		if ((U|y) == 0) {			/* inf */
172 			pu->fpclass = fp_infinity;
173 			return;
174 		} else {				/* nan */
175 			if ((U & 0x80000) != 0) {	/* quiet */
176 				pu->fpclass = fp_quiet;
177 			} else {			/* signaling */
178 				pu->fpclass = fp_signaling;
179 				fpu_set_exception(pfpsd, fp_invalid);
180 			}
181 			pu->significand[0] = 0x18000 | (U >> 4);
182 			(*pu).significand[1] = ((U&0xf)<<28)|(y>>4);
183 			(*pu).significand[2] = ((y&0xf)<<28);
184 			return;
185 		}
186 	}
187 	(*pu).exponent = x.exponent - DOUBLE_BIAS;
188 	(*pu).fpclass = fp_normal;
189 	(*pu).significand[0] = 0x10000|(U>>4);
190 	(*pu).significand[1] = ((U&0xf)<<28)|(y>>4);
191 	(*pu).significand[2] = ((y&0xf)<<28);
192 }
193 
194 static void
195 unpackextended(
196 	fp_simd_type	*pfpsd,	/* simulator data */
197 	unpacked	*pu,	/* unpacked result */
198 	extended_type	x,	/* packed extended, sign/exponent/16 bits */
199 	uint32_t	y,	/* 2nd word of extended significand */
200 	uint32_t	z,	/* 3rd word of extended significand */
201 	uint32_t	w)	/* 4th word of extended significand */
202 {
203 	uint_t U;
204 
205 	pu->sticky = pu->rounded = 0;
206 	U = x.significand;
207 	(*pu).sign = x.sign;
208 	(*pu).fpclass = fp_normal;
209 	(*pu).exponent = x.exponent - EXTENDED_BIAS;
210 	(*pu).significand[0] = (x.exponent == 0) ? U : 0x10000|U;
211 	(*pu).significand[1] = y;
212 	(*pu).significand[2] = z;
213 	(*pu).significand[3] = w;
214 	if (x.exponent < 0x7fff) {	/* zero, normal, or subnormal */
215 		if ((z|y|w|pu->significand[0]) == 0) {	/* zero */
216 			pu->fpclass = fp_zero;
217 			return;
218 		} else {			/* normal or subnormal */
219 			if (x.exponent == 0) {
220 				fpu_normalize(pu);
221 				pu->exponent += 1;
222 			}
223 			return;
224 		}
225 	} else {					/* inf or nan */
226 		if ((U|z|y|w) == 0) {			/* inf */
227 			pu->fpclass = fp_infinity;
228 			return;
229 		} else {				/* nan */
230 			if ((U & 0x00008000) != 0) {	/* quiet */
231 				pu->fpclass = fp_quiet;
232 			} else {			/* signaling */
233 				pu->fpclass = fp_signaling;
234 				fpu_set_exception(pfpsd, fp_invalid);
235 			}
236 			pu->significand[0] |= 0x8000;	/* make quiet */
237 			return;
238 		}
239 	}
240 }
241 
242 void
243 _fp_unpack(
244 	fp_simd_type	*pfpsd,	/* simulator data */
245 	unpacked	*pu,	/* unpacked result */
246 	uint_t		n,	/* register where data starts */
247 	enum fp_op_type	dtype)	/* type of datum */
248 {
249 	freg_type	f;
250 	union {
251 		uint32_t	y[4];
252 		uint64_t	ll[2];
253 		freg_type	f;
254 	} fp;
255 
256 	switch (dtype) {
257 	case fp_op_int32:
258 		pfpsd->fp_current_read_freg(&f, n, pfpsd);
259 		unpackint32(pu, f.int32_reg);
260 		break;
261 	case fp_op_int64:
262 
263 		if ((n & 0x1) == 1)	/* fix register encoding */
264 			n = (n & 0x1e) | 0x20;
265 		pfpsd->fp_current_read_dreg(&fp.ll[0], DOUBLE(n), pfpsd);
266 		unpackint64(pu, fp.f.int64_reg);
267 		break;
268 	case fp_op_single:
269 		pfpsd->fp_current_read_freg(&f, n, pfpsd);
270 		unpacksingle(pfpsd, pu, f.single_reg);
271 		break;
272 	case fp_op_double:
273 		if ((n & 0x1) == 1)	/* fix register encoding */
274 			n = (n & 0x1e) | 0x20;
275 		pfpsd->fp_current_read_dreg(&fp.ll[0], DOUBLE(n), pfpsd);
276 		unpackdouble(pfpsd, pu, fp.f.double_reg, fp.y[1]);
277 		break;
278 	case fp_op_extended:
279 		if ((n & 0x1) == 1)	/* fix register encoding */
280 			n = (n & 0x1e) | 0x20;
281 		pfpsd->fp_current_read_dreg(&fp.ll[0], QUAD_E(n), pfpsd);
282 		pfpsd->fp_current_read_dreg(&fp.ll[1], QUAD_F(n), pfpsd);
283 		unpackextended(pfpsd, pu, fp.f.extended_reg, fp.y[1],
284 					fp.y[2], fp.y[3]);
285 		break;
286 	}
287 }
288 
289 void
290 _fp_unpack_word(
291 	fp_simd_type	*pfpsd,	/* simulator data */
292 	uint32_t	*pu,	/* unpacked result */
293 	uint_t		n)	/* register where data starts */
294 {
295 	pfpsd->fp_current_read_freg(pu, n, pfpsd);
296 }
297 
298 void
299 _fp_unpack_extword(
300 	fp_simd_type	*pfpsd,	/* simulator data */
301 	uint64_t	*pu,	/* unpacked result */
302 	uint_t		n)	/* register where data starts */
303 {
304 	if ((n & 0x1) == 1)	/* fix register encoding */
305 		n = (n & 0x1e) | 0x20;
306 	pfpsd->fp_current_read_dreg(pu, DOUBLE(n), pfpsd);
307 }
308