match is used for following sequence copy. It is only updated when extDict is needed, which is a low probability case. So it can be prefetched to reduce cache miss. The benchmarks on various Arm platforms showed uplift from 1% ~ 14% with gcc-11/clang-14. Signed-off-by: Jun He <jun.he@arm.com> Change-Id: If201af4799d2455d74c79f8387404439d7f684ae