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Re: ARM patch: Reduce code duplication for Thumb2 move patterns


On 07/31/2010 03:16 PM, Richard Earnshaw wrote:
> On Thu, 2010-07-08 at 01:08 +0100, Bernd Schmidt wrote:
>> There are many patterns in thumb2.md which are duplicated with only
>> minor changes from their ARM equivalents.  This patch removes some of
>> this duplication.
>>
>> There's one functional change: the ARM movdi pattern disallows the
>> mem->mem move case while the Thumb2 one does not; I assumed that the
>> ARM
>> version was more desirable.

> This is OK.  

Thanks!

> We need to watch out, when merging patterns in this way that we don't
> increase the length calculations too much (ideally not at all).  It's
> safe, but in the long run is likely to lead to sub-optimal branch and
> literal pool generation.

I think I checked all the patterns - did you see one where the lengths
were different?


Bernd


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