Fujitsu Fujitsu SPARC64 V manual Write State Register, Deprecated Instructions, Store Barrier

Models: Fujitsu SPARC64 V

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A.70 Write State Register

In SPARC64 V, a WRPCR instruction will cause a privileged_action exception if PSTATE.PRIV = 0 and PCR.PRIV = 1. If PSTATE.PRIV = 0 and PCR.PRIV = 0, WRPCR causes a privileged_action exception only when an attempt is made to change (that is, write 1 to) PCR.PRIV (impl. dep. #250).

A.71 Deprecated Instructions

The deprecated instructions in A.71 of Commonality are provided only for compatibility with previous versions of the architecture. They should not be used in new software.

A.71.10 Store Barrier

In SPARC64 V, STBAR behaves as NOP since the hardware memory models always enforce the semantics of these MEMBARs for all memory accesses.

Release 1.0, 1 July 2002

F. Chapter A Instruction Definitions: SPARC64 V Extensions 59

Page 70
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Fujitsu Fujitsu SPARC64 V manual Write State Register, Deprecated Instructions, Store Barrier