Performance comparison, ULE vs 4BSD and AMD64 vs i386

David O'Brien obrien at
Wed Feb 25 11:00:56 PST 2004

On Wed, Feb 25, 2004 at 01:50:35PM -0500, Kenneth Culver wrote:
> Ok well maybe not with amd64, but I thought that when you add registers

This is the key word here -- "thought".  No one has done any real analsys
and thus we can't say jack.  While at first thought compiling for a large
number of GPR's could be more time consuming; I think there are other
phases of code generation where the process is slower due to lack of a
large number of GPR's.

> Like on PowerPC or Alpha or whatever there are a LOT more GPR's than
> there are on even Athlon64... I guess only having 2x the GPR's doesn't
> make a whole lot of difference...

PowerPC and Alpha are also RISC and have other scheduling issues for the
code generator to handle.

-- David  (obrien at

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