Re: [PATCH 0/2] x86: Use "er" asm constriant for add/sub

On Mon, 3 Aug 2026 16:39:55 +0100
David Laight <[email protected]> wrote:

> On Mon, 3 Aug 2026 10:49:40 -0400 (EDT)
> Nicolas Pitre <[email protected]> wrote:
> 
> > On Mon, 3 Aug 2026, David Laight wrote:
> >   
> > > The x86 instruction set only supports 32bit signed immediate values
> > > for add/sub.
> > > Replace the "ir" constraint with "er" to avoid build errors.
> > > 
> > > Found by a patch that added used mul_u64_add_u64_div_u64() to
> > > do a rounding divide by 2^32 (perhaps not the best way to do this).
> > > 
> > > A quick grep only found one other affected file.    
> > 
> > Would be a good idea adding those cases to the test module.  
> 
> They fail to compile so it isn't a big deal.
> 
David, thanks for sorting this (and all for reviewing)

Seems like everyone is happy.  What route is this taking upstream?

I held Rodrigo's driver to avoid the build breakage and would like to
get it queued up early in next cycle.  So not that urgent but nice
to be able to tick it off the list!

Thanks,

Jonathan

> 	David
> 
> > 
> > 
> > Nicolas  
>