Re: [PATCH][RFC] Consolidate -O3 torture options

[Jeff Law <law@redhat.com>]

On 07/14/2015 05:58 AM, Richard Biener wrote:
>
> The following patch tries to consolidate the -O3 torture testing
> options in the attempt to reduce testing time while not losing
> coverage.
>
> It drops testing of -funroll-all-loops (which nobody should use)
> and retains only one non-default -O3 set of options - namely
> -O3 plus those flags that would be enabled by -fprofile-use.
>
> One should hope for ~20% less time in the C and dg tortures this way.
>
> Didn't look into other tortures to apply the same yet (objc-torture?)
>
> Currently testing on x86_64-unknown-linux-gnu.
>
> For weird flag combinations we do have contributors that test
> them and regularly report bugzillas.
>
> Ok?
>
> Comments?
>
> Thanks,
> Richard.
>
> 2015-07-14  Richard Biener  <rguenther@suse.de>
>
> 	* lib/c-torture.exp (C_TORTURE_OPTIONS): Remove
> 	{ -O3 -fomit-frame-pointer },
> 	{ -O3 -fomit-frame-pointer -funroll-loops } and
> 	{ -O3 -fomit-frame-pointer -funroll-all-loops -finline-functions }
> 	in favor of
> 	{ -O3 -fomit-frame-pointer -funroll-loops -fpeel-loops -ftracer
> 	  -finline-functions }
> 	* lib/gcc-dg.exp (DG_TORTURE_OPTIONS): Likewise.
I think this is OK -- I've occasionally wondered about the additional 
coverage we get vs the amount of time spent for the various options.

I can't recall specific cases where one of those 3 options would trigger 
a failure, but the two didn't. I'm sure it's happened, but it's just 
common enough to warrant the amount of time we spend testing it.

This patch has the additional benefit that I think we can eliminate 
scanning the source for loops and eliminating the -funroll[-all]-loops 
options.   Hmm, that code may have already been dead... Hmmm.

jeff