1*0Sstevel@tonic-gate /*
2*0Sstevel@tonic-gate * CDDL HEADER START
3*0Sstevel@tonic-gate *
4*0Sstevel@tonic-gate * The contents of this file are subject to the terms of the
5*0Sstevel@tonic-gate * Common Development and Distribution License, Version 1.0 only
6*0Sstevel@tonic-gate * (the "License"). You may not use this file except in compliance
7*0Sstevel@tonic-gate * with the License.
8*0Sstevel@tonic-gate *
9*0Sstevel@tonic-gate * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
10*0Sstevel@tonic-gate * or http://www.opensolaris.org/os/licensing.
11*0Sstevel@tonic-gate * See the License for the specific language governing permissions
12*0Sstevel@tonic-gate * and limitations under the License.
13*0Sstevel@tonic-gate *
14*0Sstevel@tonic-gate * When distributing Covered Code, include this CDDL HEADER in each
15*0Sstevel@tonic-gate * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
16*0Sstevel@tonic-gate * If applicable, add the following below this CDDL HEADER, with the
17*0Sstevel@tonic-gate * fields enclosed by brackets "[]" replaced with your own identifying
18*0Sstevel@tonic-gate * information: Portions Copyright [yyyy] [name of copyright owner]
19*0Sstevel@tonic-gate *
20*0Sstevel@tonic-gate * CDDL HEADER END
21*0Sstevel@tonic-gate */
22*0Sstevel@tonic-gate /*
23*0Sstevel@tonic-gate * Copyright 2003 Sun Microsystems, Inc. All rights reserved.
24*0Sstevel@tonic-gate * Use is subject to license terms.
25*0Sstevel@tonic-gate */
26*0Sstevel@tonic-gate
27*0Sstevel@tonic-gate #pragma ident "%Z%%M% %I% %E% SMI"
28*0Sstevel@tonic-gate
29*0Sstevel@tonic-gate /*
30*0Sstevel@tonic-gate * On SPARC V8, _Q_cplx_mul(v, z, w) sets *v = *z * *w with infinities
31*0Sstevel@tonic-gate * handled according to C99.
32*0Sstevel@tonic-gate *
33*0Sstevel@tonic-gate * On SPARC V9, _Q_cplx_mul(z, w) returns *z * *w with infinities
34*0Sstevel@tonic-gate * handled according to C99.
35*0Sstevel@tonic-gate *
36*0Sstevel@tonic-gate * If z and w are both finite, _Q_cplx_mul delivers the complex
37*0Sstevel@tonic-gate * product according to the usual formula: let a = Re(z), b = Im(z),
38*0Sstevel@tonic-gate * c = Re(w), and d = Im(w); then _Q_cplx_mul delivers x + I * y
39*0Sstevel@tonic-gate * where x = a * c - b * d and y = a * d + b * c. Note that if both
40*0Sstevel@tonic-gate * ac and bd overflow, then at least one of ad or bc must also over-
41*0Sstevel@tonic-gate * flow, and vice versa, so that if one component of the product is
42*0Sstevel@tonic-gate * NaN, the other is infinite. (Such a value is considered infinite
43*0Sstevel@tonic-gate * according to C99.)
44*0Sstevel@tonic-gate *
45*0Sstevel@tonic-gate * If one of z or w is infinite and the other is either finite nonzero
46*0Sstevel@tonic-gate * or infinite, _Q_cplx_mul delivers an infinite result. If one factor
47*0Sstevel@tonic-gate * is infinite and the other is zero, _Q_cplx_mul delivers NaN + I * NaN.
48*0Sstevel@tonic-gate * C99 doesn't specify the latter case.
49*0Sstevel@tonic-gate *
50*0Sstevel@tonic-gate * C99 also doesn't specify what should happen if either z or w is a
51*0Sstevel@tonic-gate * complex NaN (i.e., neither finite nor infinite). This implementation
52*0Sstevel@tonic-gate * delivers NaN + I * NaN in this case.
53*0Sstevel@tonic-gate *
54*0Sstevel@tonic-gate * This implementation can raise spurious underflow, overflow, invalid
55*0Sstevel@tonic-gate * operation, and inexact exceptions. C99 allows this.
56*0Sstevel@tonic-gate */
57*0Sstevel@tonic-gate
58*0Sstevel@tonic-gate #if !defined(sparc) && !defined(__sparc)
59*0Sstevel@tonic-gate #error This code is for SPARC only
60*0Sstevel@tonic-gate #endif
61*0Sstevel@tonic-gate
62*0Sstevel@tonic-gate static union {
63*0Sstevel@tonic-gate int i[4];
64*0Sstevel@tonic-gate long double q;
65*0Sstevel@tonic-gate } inf = {
66*0Sstevel@tonic-gate 0x7fff0000, 0, 0, 0
67*0Sstevel@tonic-gate };
68*0Sstevel@tonic-gate
69*0Sstevel@tonic-gate /*
70*0Sstevel@tonic-gate * Return +1 if x is +Inf, -1 if x is -Inf, and 0 otherwise
71*0Sstevel@tonic-gate */
72*0Sstevel@tonic-gate static int
testinfl(long double x)73*0Sstevel@tonic-gate testinfl(long double x)
74*0Sstevel@tonic-gate {
75*0Sstevel@tonic-gate union {
76*0Sstevel@tonic-gate int i[4];
77*0Sstevel@tonic-gate long double q;
78*0Sstevel@tonic-gate } xx;
79*0Sstevel@tonic-gate
80*0Sstevel@tonic-gate xx.q = x;
81*0Sstevel@tonic-gate return (((((xx.i[0] << 1) - 0xfffe0000) | xx.i[1] | xx.i[2] | xx.i[3])
82*0Sstevel@tonic-gate == 0)? (1 | (xx.i[0] >> 31)) : 0);
83*0Sstevel@tonic-gate }
84*0Sstevel@tonic-gate
85*0Sstevel@tonic-gate #ifdef __sparcv9
86*0Sstevel@tonic-gate long double _Complex
_Q_cplx_mul(const long double _Complex * z,const long double _Complex * w)87*0Sstevel@tonic-gate _Q_cplx_mul(const long double _Complex *z, const long double _Complex *w)
88*0Sstevel@tonic-gate {
89*0Sstevel@tonic-gate long double _Complex v;
90*0Sstevel@tonic-gate #else
91*0Sstevel@tonic-gate void
92*0Sstevel@tonic-gate _Q_cplx_mul(long double _Complex *v, const long double _Complex *z,
93*0Sstevel@tonic-gate const long double _Complex *w)
94*0Sstevel@tonic-gate {
95*0Sstevel@tonic-gate #endif
96*0Sstevel@tonic-gate long double a, b, c, d, x, y;
97*0Sstevel@tonic-gate int recalc, i, j;
98*0Sstevel@tonic-gate
99*0Sstevel@tonic-gate /*
100*0Sstevel@tonic-gate * The following is equivalent to
101*0Sstevel@tonic-gate *
102*0Sstevel@tonic-gate * a = creall(*z); b = cimagl(*z);
103*0Sstevel@tonic-gate * c = creall(*w); d = cimagl(*w);
104*0Sstevel@tonic-gate */
105*0Sstevel@tonic-gate a = ((long double *)z)[0];
106*0Sstevel@tonic-gate b = ((long double *)z)[1];
107*0Sstevel@tonic-gate c = ((long double *)w)[0];
108*0Sstevel@tonic-gate d = ((long double *)w)[1];
109*0Sstevel@tonic-gate
110*0Sstevel@tonic-gate x = a * c - b * d;
111*0Sstevel@tonic-gate y = a * d + b * c;
112*0Sstevel@tonic-gate
113*0Sstevel@tonic-gate if (x != x && y != y) {
114*0Sstevel@tonic-gate /*
115*0Sstevel@tonic-gate * Both x and y are NaN, so z and w can't both be finite.
116*0Sstevel@tonic-gate * If at least one of z or w is a complex NaN, and neither
117*0Sstevel@tonic-gate * is infinite, then we might as well deliver NaN + I * NaN.
118*0Sstevel@tonic-gate * So the only cases to check are when one of z or w is
119*0Sstevel@tonic-gate * infinite.
120*0Sstevel@tonic-gate */
121*0Sstevel@tonic-gate recalc = 0;
122*0Sstevel@tonic-gate i = testinfl(a);
123*0Sstevel@tonic-gate j = testinfl(b);
124*0Sstevel@tonic-gate if (i | j) { /* z is infinite */
125*0Sstevel@tonic-gate /* "factor out" infinity */
126*0Sstevel@tonic-gate a = i;
127*0Sstevel@tonic-gate b = j;
128*0Sstevel@tonic-gate recalc = 1;
129*0Sstevel@tonic-gate }
130*0Sstevel@tonic-gate i = testinfl(c);
131*0Sstevel@tonic-gate j = testinfl(d);
132*0Sstevel@tonic-gate if (i | j) { /* w is infinite */
133*0Sstevel@tonic-gate /* "factor out" infinity */
134*0Sstevel@tonic-gate c = i;
135*0Sstevel@tonic-gate d = j;
136*0Sstevel@tonic-gate recalc = 1;
137*0Sstevel@tonic-gate }
138*0Sstevel@tonic-gate if (recalc) {
139*0Sstevel@tonic-gate x = inf.q * (a * c - b * d);
140*0Sstevel@tonic-gate y = inf.q * (a * d + b * c);
141*0Sstevel@tonic-gate }
142*0Sstevel@tonic-gate }
143*0Sstevel@tonic-gate
144*0Sstevel@tonic-gate #ifdef __sparcv9
145*0Sstevel@tonic-gate ((long double *)&v)[0] = x;
146*0Sstevel@tonic-gate ((long double *)&v)[1] = y;
147*0Sstevel@tonic-gate return (v);
148*0Sstevel@tonic-gate #else
149*0Sstevel@tonic-gate ((long double *)v)[0] = x;
150*0Sstevel@tonic-gate ((long double *)v)[1] = y;
151*0Sstevel@tonic-gate #endif
152*0Sstevel@tonic-gate }
153