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Re: Optimization Switches


On Friday 27 August 2010 06:07 AM, Paul Brook wrote:
Hi,
I wish to selectively enable specific optimizations to observe its effect
on the source. My project requires me to do this analysis. It seemed, the
-f* flags would enable me to do that. But it turns out that individual
optimizations can't be enabled like that, and all the optimizations at a
specific level gets enabled when I use a  -Ox switch. This faq  at
http://gcc.gnu.org/wiki/FAQ#optimization-options, says this too.

So here are my two questions :

a) Is there any way to observe the effect of a particular optimization,
without the obvious option of using a lot of -fno switches.
b) And do the -f* switches serve any purpose, if I can't enable individual
optimizations using them.
I suspect that in practice that this isn't a particularly interesting
question.  Optimizations often interact with each other in complex ways, with
the end result being significantly different to the naive sum of their parts.

Paul
This is precisely what I want, segregating the effect of every single optimization. :)
--
Sharjeel



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