Intel ITANIUM ARCHITECTURE - SOFTWARE DEVELOPERS MANUAL VOLUME 1 REV 2.3 Manual page 744

PAL_VPS_SET_PENDING_INTERRUPT
PAL_VPS_SET_PENDING_INTERRUPT performs the following actions:
• Copy the virtual highest priority pending interrupt from the VPD into
implementation-specific resources.
• Return to VMM by an indirect branch specified in the GR24 parameter.
2:496 Volume 2, Part 1: Processor Abstraction Layer