test vectors from ucbtest/ucblib
http://www.netlib.org/fp/ucbtest.tgz
powd.input is fixed to match posix

format:
	/* comment */
	func1 round check except in out
	func2 round check except in1 in2 out

func1: function with 1 input arg
func2: function with 2 input args

round:
	n = to nearest
	z = to zero
	p = to +inf
	m = to -inf

check:
	eq = equal
	nb = nearby (abserr < 10 ulp)
	vn = very near (abserr < 3ulp)
	uo = unordered (nan)
	ge = greater or equal
	le = less or equal

except:
	v = invalid
	x = inexact
	o = overflow
	u = underflow
	d = div by zero
	- = no except
	? = next except is optional

in:
out:
	n 32bit words in hex
		single precision: n = 1
		double precision: n = 2
		quad precision: n = 4