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Re: [PATCH] Don't depend on LIM to determine loop end in __sqr
- From: Andreas Jaeger <aj at suse dot com>
- To: libc-alpha at sourceware dot org
- Date: Fri, 15 Feb 2013 16:43:54 +0100
- Subject: Re: [PATCH] Don't depend on LIM to determine loop end in __sqr
- References: <20130214112619.GF11884@spoyarek.pnq.redhat.com>
On 02/14/2013 12:26 PM, Siddhesh Poyarekar wrote:
Hi,
This is yet another micro-optimization to the __sqr loop termination.
If we check the termination condition of the inner mantissa
calculation loop as the subscripts of X and Y crossing over, we don't
need the extra operations in LIM. This gives a roughly 2% improvement
in pow() in the worst case (768 bits). Built and tested on x86_64.
Will work on ppc changes separately. OK to commit?
Yes,
Andreas
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