Load Program Status Word instruction
Appearance
In the System/360 line of IBM mainframe computers up to contemporary zSeries, Load Program Status Word instruction (LPSW) is a privileged instruction used to restore the program status, including the program mode and protection key, and the next sequential instruction address after the interruption. The interruption could be any of a set of interruptions (SVC, I/O, timer/external, etcetera).
LPSW could be considered the "complement" of any interruption, in general, and an SVC interruption, in particular, as the return from such interruptions is effected by a LPSW instruction.