>>>>> "Kevin P. Lawton" <[EMAIL PROTECTED]> writes:
Kevin>
Kevin> This can have performance implications
Kevin> for fine-grained user-level threading where each thread
Kevin> context switch necessitates spilling and filling of all
Kevin> register frames. Since there's a lot of registers available
Kevin> on this architecture, liberal use of them by generated
Kevin> code in a compiler would make this worse. I'll be interested
Kevin> to see how Merced benchmarks out in the threading department.
Kevin> My take was that the SPARC people didn't think that using Windowed
Kevin> Registers was such as hot idea in retrospect...
Two things make the IA-64 register windows more attractive than the
SPARC ones:
1. They are not of fixed size.
2. IA-64 has architectural support for saving and restoring windows
in the background (although SPARC register windows have become
cheaper to save and restore in recent implementations).
/Magnus
