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Re: [PATCH 4/4] arm: Enable ARM mode for armv6 strlen



On 11/04/2018 19:12, Phil Blundell wrote:
> On Wed, 2018-04-11 at 18:16 -0300, Adhemerval Zanella wrote:
>> Current optimized armv6t2 strlen uses the NO_THUMB wrongly to
>> conditionalize thumb instruction usage.  The flags is meant to be
>> defined before sysdep.h inclusion and to indicate the assembly
>> requires to build in ARM mode, not to check whether thumb is
>> enable or not.  This patch fixes it by using the GCC provided
>> '__thumb__' instead.
> 
> Is it ever useful to build for ARM-state when on armv6t2 (i.e. Thumb2
> is guaranteed to be available)?  It's not totally obvious from reading
> the source that the ARM version is going to be better in any way than
> the Thumb one.

I guess not, but even though the implementation allows it and the flag
usage is wrong.  Another option would just remove ARM code, but I think
for this we will need to also add configure check to require thumb as
well.

> 
> Assuming that this is indeed something worth supporting, I think the
> short log for the patch ought to say "armv6t2" not "armv6".

Right, I changed it locally. 


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