Help with performance issues.

Jeff Sturm
Mon Jul 30 09:21:00 GMT 2001

On Mon, 30 Jul 2001, Boehm, Hans wrote:
> Another problem that we've sometimes seen in code like this is that the
> array null pointer checks don't completely disappear, at least not on
> Itanium.  On 32-bit machines this may be hard to avoid.  On 64-bit machines,
> it might be possible to arrange that there is nothing mapped within the
> first 32GB of address space, so that accesses through null array pointers
> are also guaranteed to result in an identifiable SIGSEGV.  Does this make
> sense?

If I'm not mistaken, Java array indexes are signed int, so the max array
size is really 16GB.  But that sounds OK.  On alpha, stack grows download
below .text so I'd guess a hard stack limit would be necessary.


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