RESTRICTED INSTRUCTIONS IN TRANSACTIONAL EXECUTION

摘要

Restricted instructions are prohibited from execution within a transaction. There are classes of instructions that are restricted regardless of type of transaction: constrained or nonconstrained. There are instructions only restricted in constrained transactions, and there are instructions that are selectively restricted for given transactions based on controls specified on instructions used to initiate the transactions.

主权项

1. A computer program product for performing processing associated with transactional execution in a computing environment, the computer program product comprising:
a computer readable storage medium readable by a processing circuit and storing instructions for execution by the processing circuit for performing a method comprising:
obtaining, by a processor, an instruction to be executed as part of a transaction;computing one or more effective controls from one or more controls set by one or more transaction begin instructions, wherein the one or more effective controls comprises an effective allow access register modification control that indicates whether an access register is permitted to be modified;determining by the processor whether the instruction is a selectively restricted instruction that is prohibited from execution within the transaction, the determining being based on the computed one or more effective controls; andperforming processing associated with the instruction based on whether the instruction is selectively restricted.