FreeBSD 5.2 v/s FreeBSD 4.9 MFLOPS performance (gcc3.3.3 v/s gcc2.9.5)

Dag-ErlingSmørgrav des at des.no
Mon Feb 16 10:11:25 PST 2004


Kris Kennaway <kris at obsecurity.org> writes:
> On Mon, Feb 16, 2004 at 03:52:16AM -0800, Wes Peters wrote:
> > Should I commit this?
> What effect does it have on non-i386 architectures?

It can't possibly hurt.  If the stack is already aligned on a "better"
boundary (64 or 128 bytes), it is also aligned on a 32-byte boundary
since 64 and 128 are multiples of 32, and the patch is a no-op.  If
only a 16-byte alignment is required, a 32-byte alignment wastes a
small amount of memory but does not hurt performance.  I believe that
less-than-16 (and possibly even less-than-32) alignment is pessimal on
all platforms we support.

DES
-- 
Dag-Erling Smørgrav - des at des.no


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