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From: Wojtek Lerch <wojtek_l@yahoo.ca>
Newsgroups: comp.std.c
Subject: Re: Loop Invariance Optimization Opportunity?
Date: Fri, 18 Jan 2013 12:25:16 -0500
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On 18-Jan-13 8:25 AM, Shao Miller wrote:
> GCC without an -O, with -O2, and with -O3 didn't make any difference in
> the behaviour.  If an invariance optimization is used, the loop should
> iterate 42 times, instead of 21.

Have you tried you moving "looper" into a separate translation unit?

I'm getting 42 with GCC 4.4.2, but 21 with GCC 4.6.3.