Optimize opcodes to avoid bubble in pipeline.

Possible bubbles between fetch(ldr) and extract(and)
Excute subsequent instruction(s) inbetween the bubble by reordering instruction.

Change-Id: I76d89ed6bc4ca44673231375cc529fdbfd5a8030
Possible leak in dvmAllocRegion

In error case mmapped ptr 'base' is not munmapped.

Change-Id: I9e43841371fee6b7c092fe9a8922ae82e78805ed