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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.
package runtime
func complex128div(n complex128, d complex128) complex128 {
// Special cases as in C99.
ninf := real(n) == posinf || real(n) == neginf ||
imag(n) == posinf || imag(n) == neginf
dinf := real(d) == posinf || real(d) == neginf ||
imag(d) == posinf || imag(d) == neginf
nnan := !ninf && (real(n) != real(n) || imag(n) != imag(n))
dnan := !dinf && (real(d) != real(d) || imag(d) != imag(d))
switch {
case nnan || dnan:
return complex(nan, nan)
case ninf && !dinf:
return complex(posinf, posinf)
case !ninf && dinf:
return complex(0, 0)
case real(d) == 0 && imag(d) == 0:
if real(n) == 0 && imag(n) == 0 {
return complex(nan, nan)
} else {
return complex(posinf, posinf)
}
default:
// Standard complex arithmetic, factored to avoid unnecessary overflow.
a := real(d)
if a < 0 {
a = -a
}
b := imag(d)
if b < 0 {
b = -b
}
if a <= b {
ratio := real(d) / imag(d)
denom := real(d)*ratio + imag(d)
return complex((real(n)*ratio+imag(n))/denom,
(imag(n)*ratio-real(n))/denom)
} else {
ratio := imag(d) / real(d)
denom := imag(d)*ratio + real(d)
return complex((imag(n)*ratio+real(n))/denom,
(imag(n)-real(n)*ratio)/denom)
}
}
}
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