short pointers (32 bit) in 64 bit apps

[Clemens Eisserer]

Hi,

> Is there support for "short" pointers in 64 bit applications?  As struct members, these short pointers would save space, but when accessed, they would
> automatically be treated as 64 bit pointers into the "current" 4GB space (namely where the containing struct resides.)

Sun's JVM is able to do this, they even have two different cases for
<= 4GB heaps and <= 32GB heaps, and at least for "typical" java
applications the speedup is in the range of 10-25%,

- Clemens