Cray CRAY-1 - Page 122

The 046 instruction forms the logical difference (exclusive OR) of
(Sj) and (Sk) and enters the result into Si. Bits of Si are set to
one when the corresponding bits of (Sj) and (Sk) are different as in
the following
example:
(Sj) = 1 1 0 0
(Sk) = 1 0 1 0
(Si) = 0 1 1 0
Si is cleared if the j and k designators have the same nonzerc value.
~Sk) is transmitted to Si if the j designator is zero and the k
designator is nonzero. The sign bit of (Sj) ;s complemented and the
result is transmitted to Si if the j designator is nonzero and the
k designator
is zero.
The 047 instruction forms the logical equivalence of (Sj) and (Sk), and
enters the result into Si. Bits of Si are set to one when the
corresponding
bits of (Sj) and (Sk) are the same as in the
following
example:
(Sj) = 1 1 0 0
(Sk) = 1 0 1 0
(Si) = 100 1
Si is set to all ones if the j and k designators have the same nonzero
value. The complement of (Sk) is transmitted to Si if the j designator
is zero and the k designator is nonzero. All bits except the sign bit.
of (Sj) are complemented and the result is transmitted to Si if the j
designator
is nonzero and the k designator is zero.
The 050 instruction merges the contents of (Sj) with (Si) depending
on the ones mask in Sk. The result is defined by the Boolean equation
(Si) = (Sj)(Sk) + (Si)(Sk) as illustrated in the following example:
2240004
(Sk) = 1 1 1 1 0 0 0 0
(Si)
= 1 1 0 0 1 1 0 0
(Sj)
= 1 0 1 0 1 0 1 0
(Si) = 1 0 1 0 1 1 0 0
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