On 04/29/2016 03:35 AM, Dominik Vogt wrote:
On Wed, Apr 27, 2016 at 10:24:21PM -0600, Jeff Law wrote:
Instead you want insn 12 to use a zero-extend to extend (reg:SI 64)
into (reg:DI 2)?
Yes, because we get the zero extend for free in this case (through
the constant in the AND or because the i
On Tue, May 10, 2016 at 12:07 PM, Dominik Vogt wrote:
> On Tue, May 10, 2016 at 11:14:35AM +0200, Richard Biener wrote:
>> On Mon, May 9, 2016 at 3:36 PM, Marc Glisse wrote:
>> > On Mon, 9 May 2016, Dominik Vogt wrote:
>> >
>> >> This turns out to be quite difficult. A small test function
>> >>
On Tue, May 10, 2016 at 11:14:35AM +0200, Richard Biener wrote:
> On Mon, May 9, 2016 at 3:36 PM, Marc Glisse wrote:
> > On Mon, 9 May 2016, Dominik Vogt wrote:
> >
> >> This turns out to be quite difficult. A small test function
> >> effectively just returns the argument:
> >>
> >> unsigned lon
On Mon, May 9, 2016 at 3:36 PM, Marc Glisse wrote:
> On Mon, 9 May 2016, Dominik Vogt wrote:
>
>> This turns out to be quite difficult. A small test function
>> effectively just returns the argument:
>>
>> unsigned long bar (unsigned long in)
>> {
>>if ((in & 1) == 0)
>> in = (in & ~(u
On Mon, 9 May 2016, Dominik Vogt wrote:
This turns out to be quite difficult. A small test function
effectively just returns the argument:
unsigned long bar (unsigned long in)
{
if ((in & 1) == 0)
in = (in & ~(unsigned long)1);
return in;
}
However, Gcc does not notice that the
On Wed, Apr 27, 2016 at 10:24:21PM -0600, Jeff Law wrote:
> On 04/27/2016 02:20 AM, Dominik Vogt wrote:
> >The attached patch is a result of discussing an S/390 issue with
> >"and with complement" in some cases.
> >
> > https://gcc.gnu.org/ml/gcc/2016-03/msg00163.html
> > https://gcc.gnu.org/ml/g
On Wed, Apr 27, 2016 at 10:24:21PM -0600, Jeff Law wrote:
> On 04/27/2016 02:20 AM, Dominik Vogt wrote:
> > * combine.c (make_compound_operation): Take known zero bits into
> > account when checking for possible zero_extend.
> I'd strongly recommend writing some tests for this. Extra credi
On 04/27/2016 02:20 AM, Dominik Vogt wrote:
The attached patch is a result of discussing an S/390 issue with
"and with complement" in some cases.
https://gcc.gnu.org/ml/gcc/2016-03/msg00163.html
https://gcc.gnu.org/ml/gcc-patches/2016-04/msg01586.html
Combine would merge a ZERO_EXTEND and a
cking for possible zero_extend.
>From e70e6e469200b53b3f4ae52a766cdd322a4d365d Mon Sep 17 00:00:00 2001
From: Dominik Vogt
Date: Tue, 12 Apr 2016 09:53:46 +0100
Subject: [PATCH] Take known zero bits into account when checking
extraction.
Allows AND Insns with a const_int operand to be expres
