[llvm-commits] [PATCH] Disable ARM partial flag dependency optimization at -Oz

[Quentin Colombet]

Hi,

Thanks for the reviews.

I'd like Jim's idea about caching the information in a local class variable.
I've updated the patch accordingly.

New patch attached.

-Quentin


On Dec 18, 2012, at 1:00 PM, Renato Golin <rengolin at systemcall.org> wrote:

> On 18 December 2012 20:18, Jim Grosbach <grosbach at apple.com> wrote:
>> The command line options aren't really available here, and we'd have to check for a function-local override anyway, so I don't think that'll work out.
> 
> True, I forgot about that.
> 
> 
>> Is there concern here the potential compile time impact? Accessing the attribute list should be pretty quick (a couple of pointer indirections and a bit mask).
> 
> Mainly, yes, but I agree it's not a big problem.
> 
> 
>> If we want, we could cache the value locally in the size reduction pass as a local class ivar and initialize it at the start of runOnMachineFunction(). That would make the access a single pointer indirection off the 'this' pointer for the pass.
> 
> If that pass would only run on a single module, that'd make sense. But
> if you could run it (opt) on a collation of different modules,
> possibly compiled with different flags, than I'd think you'd need the
> full check.
> 
> I agree that the lookup is cheap, sorry for having over-complicated things. ;)
> 
> LGTM.
> 
> cheers,
> --renato

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