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RE: Help with performance issues.
- To: "Boehm, Hans" <hans_boehm at hp dot com>
- Subject: RE: Help with performance issues.
- From: Jeff Sturm <jsturm at one-point dot com>
- Date: Mon, 30 Jul 2001 12:22:50 -0400 (EDT)
- cc: "'Anthony Green'" <green at redhat dot com>, wjb at netpd dot com, java at gcc dot gnu dot org
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.
Jeff