The C2 compiler could improve the speed of handling longs in
the 64 bit VM by maintaining all longs in single 64 bit Sparc V9 registers,
rather than in 2 Sparc registers as in the 32 bit VM.

The Sparc stack should be converted to a 32 bit Stack in order to
save memory. Longs and Pointers are the only data types that should
use up 64 bits of stack space. Currently all data types consume 64 bit
of stack space.