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Re: detailed comparison of generated code size for GCC and other compilers
On Mon, Dec 14, 2009 at 5:30 PM, John Regehr <regehr@cs.utah.edu> wrote:
>> I wonder if the original program was already broken or was this
>> something your conversion introduced?
>
> Not sure about this specific case but I'm sure there's some of each.
>
> I also noticed these testcases but decided to leave them in for now.
> Obviously the code is useless, but it can still be interpreted according to
> the C standard, and code can be generated. ?Once you start going down the
> road of exploiting undefined behavior to create better code -- and gcc
> already does this pretty aggressively -- why not keep going?
>
> That said, if there's a clear sentiment that this kind of test case is
> undesirable, I'll make an effort to get rid of these for subsequent runs.
+1 for undesirable. Benchmarks are already always artificial, but
benchmarks of undefined code are not going to give useful comparisons.
Ciao!
Steven