Multi-function instruction that determines whether functions are installed on a system

摘要

A method, system and program product for executing a multi-function instruction in an emulated computer system by specifying, via the multi-function instruction, either a capability query or execution of a selected function of one or more optional functions, wherein the selected function is an installed optional function, wherein the capability query determines which optional functions of the one or more optional functions are installed on the computer system.

主权项

1. A computer program product for executing a multi-function instruction for performing a multi-function operation in a computer system, the computer program product comprising:
a non-transitory storage medium readable by a processor storing instructions for execution by the processor and the processor comprising an instruction fetching element for fetching instructions from memory of a first computer architecture and executed by the processor of an alternate computer architecture and one or more execution elements for interpreting the fetched instructions to identify a predetermined software subroutine for emulating the operation of the fetched instructions, the predetermined software subroutine comprising a plurality of instructions; and executing the predetermined software subroutine to perform: configuring a processor of a computer system to execute the multi-function instruction, the multi-function instruction configured to perform a multi-function operation, the processor configured to perform a method comprising:
1) responsive to the multi-function operation to be performed being a function query operation, performing a) and b), comprising:
a) determining, by the processor, for each of one or more multi-function operations whether a corresponding multi-function function is installed on the computer system for execution by a multi-function instruction; andb) saving, by the processor, a status word, the status word comprising one or more status word bits, each one of the one or more status word bits indicating whether a corresponding multi-function function is installed on the computer system, each one of the one or more status word bits having a position in the status word corresponding to the corresponding multi-function function; and2) responsive to the multi-function operation to be performed being a multi-function operation other than a function query operation, performing, by the processor, the multi-function operation; and3) providing the processor of the computer system, which has been configured, to execute the multi-function instruction.