[PATCH 1/2] simplify-rtx: The truncation of an IOR can have all bits set (PR81423)

[Segher Boessenkool]

On Wed, Jul 19, 2017 at 12:19:32AM -0600, Jeff Law wrote:
> On 07/18/2017 01:36 PM, Segher Boessenkool wrote:
> > ... if it is an IOR with a constant with all bits set in the mode
> > that is truncated to, for example.  Handle that case.
> > 
> > With this patch the problematic situation for the PR81423 testcase
> > isn't even reached; but the next patch fixes that anyway.
> > 
> > Bootstrapped and tested on powerpc64-linux {-m32,-m64} and on
> > x86_64-linux.  Is this okay for trunk?
> > 
> > 
> > Segher
> > 
> > 
> > 2017-07-18  Segher Boessenkool  <segher@kernel.crashing.org>
> > 
> > 	PR rtl-optimization/81423
> > 	* simplify-rtx.c (simplify_truncation): Handle truncating an IOR
> > 	with a constant that is -1 in the truncated to mode.
> OK.  A testcase would be advisable :-)

Thanks.  Yes, I have one, it's not ready yet though (I'm making it not
target specific, it seems ideal for torturing).


Segher