4 Instructions

4.1 Supervisor CTR Clear Instruction

The SCTRCLR instruction performs the following operations:

• Zeroes all CTR Entry Registers, for all DEPTH values
• Zeroes the CTR cycle counter and CCV (see Section 6.3)

Any read of ctrsource, ctrtarget, or ctrdata that follows SCTRCLR, such that it precedes the next qualified control transfer, will return the value 0. Further, the first recorded transfer following SCTRCLR will have ctrdata.CCV=0.

SCTRCLR raises an illegal-instruction exception in U-mode, and a virtual-instruction exception in VU-mode, unless CTR state enable access restrictions apply. See Section 5.