The fix JDK-8151163 updates ByteBuffer and views to consistently leverage the Unsafe.get*Unaligned methods.

On platforms where those methods are intrinsic performance is improved, such as on x86, which supports unaligned loads/stores.

On SPARC, which does not natively support unaligned loads/stores, those methods are not intrinsic, and the Java implementation is leveraged. Initial performance analysis indicates that JDK-8151163 introduces a regression on SPARC for misalignment when loading/storing bytes is necessary, which requires 3 misalignment checks before such bytes are accessed.

Analysis of generated code is required to better understand how Unsafe access behaves, especially in unrolled loops.

A new Unsafe method that explicitly separates out the possibly misaligned base from an aligned (per unit size) offset may help, since the base misalignment check could be hoisted out of a loop.

Making get*Unaligned intrinsic may also help. For example, performing two aligned load instructions and then extracting the misaligned value (see instructions FALIGNDATA and ALIGNADDRESS http://www.oracle.com/technetwork/server-storage/sun-sparc-enterprise/documentation/sparc-architecture-2015-2868130.pdf).