MIPS64: Adjust Base and Offset

Minimize the number of statements needed to load/store data at an
arbitrary offset from a base register.

Test: test-art-host-gtest
Test: ART_TEST_OPTIMIZING=true test-art-target-run-test

Change-Id: I76cc4b715dbb5b41c76b3c537fbd62bae8409bc0
3 files changed