4.11.6 Implementation Version

Format:

IMPLVER

Rc

!Operate format

Operation:

Rc value, which is defined in Appendix D

Exceptions:

None

Instruction mnemonics:

IMPLVER

Implementation Version

Description:

A small integer is placed in Rc that specifies the major implementation version of the proces- sor on which it is executed. This information can be used to make code-scheduling or tuning decisions, or the information can be used to branch to different pieces of code optimized for different implementations.

Notes:

The value returned by IMPLVER does not identify the particular processor type. Rather, it identifies a group of processors that can be treated similarly for performance characteristics such as scheduling. Ra must be R31 and Rb must be the literal #1 or the result in Rc is UNPREDICTABLE and it is UNPREDICTABLE whether an exception is signaled.

Software Note:

Use this instruction to make code-tuning decisions; use AMASK to make instruction-set decisions.

Instruction Descriptions 4–141

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Compaq ECQD2KCTE manual Implementation Version, Implver