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// Copyright 2010 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
#include "runtime.h"
typedef struct Complex128 Complex128;
void
·complex128div(Complex128 n, Complex128 d, Complex128 q)
{
int32 ninf, dinf, nnan, dnan;
float64 a, b, ratio, denom;
// Special cases as in C99.
ninf = isInf(n.real, 0) || isInf(n.imag, 0);
dinf = isInf(d.real, 0) || isInf(d.imag, 0);
nnan = !ninf && (isNaN(n.real) || isNaN(n.imag));
dnan = !dinf && (isNaN(d.real) || isNaN(d.imag));
if(nnan || dnan) {
q.real = NaN();
q.imag = NaN();
} else if(ninf && !dinf && !dnan) {
q.real = Inf(0);
q.imag = Inf(0);
} else if(!ninf && !nnan && dinf) {
q.real = 0;
q.imag = 0;
} else if(d.real == 0 && d.imag == 0) {
if(n.real == 0 && n.imag == 0) {
q.real = NaN();
q.imag = NaN();
} else {
q.real = Inf(0);
q.imag = Inf(0);
}
} else {
// Standard complex arithmetic, factored to avoid unnecessary overflow.
a = d.real;
if(a < 0)
a = -a;
b = d.imag;
if(b < 0)
b = -b;
if(a <= b) {
ratio = d.real/d.imag;
denom = d.real*ratio + d.imag;
q.real = (n.real*ratio + n.imag) / denom;
q.imag = (n.imag*ratio - n.real) / denom;
} else {
ratio = d.imag/d.real;
denom = d.imag*ratio + d.real;
q.real = (n.imag*ratio + n.real) / denom;
q.imag = (n.imag - n.real*ratio) / denom;
}
}
FLUSH(&q);
}
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