1/* This file is distributed under the University of Illinois Open Source
2 * License. See LICENSE.TXT for details.
3 */
4
5#include "DD.h"
6#include "../int_math.h"
7
8#define makeFinite(x) { \
9    (x).s.hi = crt_copysign(crt_isinf((x).s.hi) ? 1.0 : 0.0, (x).s.hi); \
10    (x).s.lo = 0.0;                                                     \
11  }
12
13#define zeroNaN(x) { \
14    if (crt_isnan((x).s.hi)) {                                          \
15      (x).s.hi = crt_copysign(0.0, (x).s.hi);                     \
16      (x).s.lo = 0.0;                                                   \
17    }                                                                   \
18  }
19
20long double __gcc_qadd(long double, long double);
21long double __gcc_qsub(long double, long double);
22long double __gcc_qmul(long double, long double);
23
24long double _Complex
25__multc3(long double a, long double b, long double c, long double d)
26{
27	long double ac = __gcc_qmul(a,c);
28	long double bd = __gcc_qmul(b,d);
29	long double ad = __gcc_qmul(a,d);
30	long double bc = __gcc_qmul(b,c);
31
32	DD real = { .ld = __gcc_qsub(ac,bd) };
33	DD imag = { .ld = __gcc_qadd(ad,bc) };
34
35	if (crt_isnan(real.s.hi) && crt_isnan(imag.s.hi))
36	{
37		int recalc = 0;
38
39		DD aDD = { .ld = a };
40		DD bDD = { .ld = b };
41		DD cDD = { .ld = c };
42		DD dDD = { .ld = d };
43
44		if (crt_isinf(aDD.s.hi) || crt_isinf(bDD.s.hi))
45		{
46			makeFinite(aDD);
47			makeFinite(bDD);
48			zeroNaN(cDD);
49			zeroNaN(dDD);
50			recalc = 1;
51		}
52
53		if (crt_isinf(cDD.s.hi) || crt_isinf(dDD.s.hi))
54		{
55			makeFinite(cDD);
56			makeFinite(dDD);
57			zeroNaN(aDD);
58			zeroNaN(bDD);
59			recalc = 1;
60		}
61
62		if (!recalc)
63		{
64			DD acDD = { .ld = ac };
65			DD bdDD = { .ld = bd };
66			DD adDD = { .ld = ad };
67			DD bcDD = { .ld = bc };
68
69			if (crt_isinf(acDD.s.hi) || crt_isinf(bdDD.s.hi) ||
70                            crt_isinf(adDD.s.hi) || crt_isinf(bcDD.s.hi))
71			{
72				zeroNaN(aDD);
73				zeroNaN(bDD);
74				zeroNaN(cDD);
75				zeroNaN(dDD);
76				recalc = 1;
77			}
78		}
79
80		if (recalc)
81		{
82			real.s.hi = CRT_INFINITY * (aDD.s.hi*cDD.s.hi - bDD.s.hi*dDD.s.hi);
83			real.s.lo = 0.0;
84			imag.s.hi = CRT_INFINITY * (aDD.s.hi*dDD.s.hi + bDD.s.hi*cDD.s.hi);
85			imag.s.lo = 0.0;
86		}
87	}
88
89	long double _Complex z;
90	__real__ z = real.ld;
91	__imag__ z = imag.ld;
92
93	return z;
94}
95