[U-Boot] [PATCH] arm: make arch memset/memcpy to work with Thumb2 builds

[Albert ARIBAUD]

Hello Jeroen,

Adding Stefan as it seems he was dropped from the recipients list.

Plus :

On Thu, 20 Nov 2014 20:14:01 +0100, Jeroen Hofstee
<jeroen at myspectrum.nl> wrote:
> Hi,
> 
> On 20-11-14 19:21, Bill Pringlemeir wrote:
> >>>> ---
> >>>> arch/arm/lib/memset.S | 40 ++++++++++++++++++++--------------------
> >>>> 1 file changed, 20 insertions(+), 20 deletions(-)
> >>>>
> >>>> diff --git a/arch/arm/lib/memset.S b/arch/arm/lib/memset.S
> >>>> index 0cdf895..4fe38f6 100644
> >>>> --- a/arch/arm/lib/memset.S
> >>>> +++ b/arch/arm/lib/memset.S
> >>>>>> -18,8 +18,8 @@
> >>>> 1:	subs	r2, r2, #4		@ 1 do we have enough
> >>>> 	blt	5f			@ 1 bytes to align with?
> >>>> 	cmp	r3, #2			@ 1
> >>>> -	strltb	r1, [r0], #1		@ 1
> >>>> -	strleb	r1, [r0], #1		@ 1
> >>>> +	strblt	r1, [r0], #1		@ 1
> >>>> +	strble	r1, [r0], #1		@ 1
> >>> To test this, can we just use 'objdump'.  The hex codes should be
> >>> identical; there is only one encoding.  It should produce the same
> >>> binaries.  No need to run test-suites, etc.
> > On 20 Nov 2014, jeroen at myspectrum.nl wrote:
> >
> >> yes, I should be trivial to test (and find the trivial problem, with
> >> the patch I attached). I am wondering though if all version of
> >> gas accept the suffix notation... any idea?
> > One part of the answer is here,
> >
> >   https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;a=history;f=gas/config/tc-arm.c;hb=HEAD
> >
> > The 'strCCb' version is definitely more popular in older ARM books.
> > Certainly there could be bugs and/or patched versions that make a
> > difference.  Probably it would be helpful to know what versions are
> > supported.
> >
> > Back in 1999 it seems that the code at least tries to take conditions
> > anywhere,
> >
> >   https://sourceware.org/git/gitweb.cgi?p=binutils-gdb.git;a=blob;f=gas/config/tc-arm.c;hb=858f4ff6ff40a73f2a569fc8886157568f08c6db#l6099
> >
> > I think it is most likely to result in a parse error if it wasn't
> > supported.  Any version since Thumb2/Unified (2003-2005?) was introduced
> > should be accepting this syntax with less issues.  Ie, it seems like a
> > better way forward.
> >
> > Historical versions are here,
> >
> > http://ftp.mirrorservice.org/sites/sourceware.org/pub/binutils/old-releases/
> >
> > Who knows if some vendor patched things to mess something up?  Probably
> > grabbing an older 'gas' version and verifying it was the same binary
> > before/after the patch would probably be fair confirmation?  I don't
> > think you can 100% guarantee this doesn't break with some archaic
> > vendors gas.
> 
> Ok thanks for digging that up, that doesn't sound like a problem
> then. Stefan, can you check if you can actually fix the warnings
> instead of suppressing them?

(in the right thread this time) Stefan, can you also drop the
-mauto-it part?

> Regards,
> Jeroen

Amicalement,
-- 
Albert.