ADDIS $1000, R3, R4             // 3c8303e8

	ANDCC $1, R3                    // 70630001
	ANDCC $1, R3, R4                // 70640001
	ANDCC $-1, R4                   // 3be0ffff7fe42039
	ANDCC $-1, R4, R5               // 3be0ffff7fe52039
	ANDCC $65535, R5                // 70a5ffff
	ANDCC $65535, R5, R6            // 70a6ffff
	ANDCC $65536, R6                // 74c60001
	ANDCC $65536, R6, R7            // 74c70001

or assignment are not yet evaluated.
</li>

<li>
If one or more of the communications can proceed,
a single one that can proceed is chosen via a uniform pseudo-random selection.
Otherwise, if there is a default case, that case is chosen.
If there is no default case, the "select" statement blocks until
at least one of the communications can proceed.
</li>

<li>