An exemplary embodiment of the invention is a method and system for
managing a result returned from a translator co-processor to a recovery
unit of a central processor. The computer system has a pipelined computer
processor and a pipelined central processor, which executes an instruction
set in a hardware controlled execution unit and executes an instruction
set in a milli-mode architected state with a millicode sequence of
instructions in the hardware controlled execution unit. The central
processor initiates a request to the translator co-processor a cycle after
decode of a perform translator operation instruction in the millicode
sequence. The translator co-processor processes the perform translator
operation instruction to generate a perform translator operation result.
The translator co-processor returns the results to a recovery unit of the
central processor. The recovery unit stores the perform translator
operation result in a system register. The request for the perform
translator operation result by the central processor is interlocked by a
hardware interlock of the recovery unit until the translator co-processor
returns the perform translator operation result. The mechanism allows the
recovery unit to maintain the correct perform translator operation result
with speculative execution and instruction level retry recovery throughout
the duration of the perform translator operation.