On Tue, Mar 18, 2014 at 11:11 AM, Richard Biener
wrote:
> Btw, without this zeroing (where zero is also "undefined") this may
> be an information leak and thus possibly a security issue? That is,
> how is _mm_undefined_pd () specified?
People aren't accidentally using the _mm*_undefined_*() func
On Tue, Mar 18, 2014 at 4:03 PM, Ulrich Drepper wrote:
> On Tue, Mar 18, 2014 at 7:13 AM, Richard Biener
> wrote:
>> extern __inline __m512
>> __attribute__ ((__gnu_inline__, __always_inline__, __artificial__))
>> _mm512_undefined_ps (void)
>> {
>> __m512 __Y = __Y;
>> return __Y;
>> }
>
>
>
On Tue, Mar 18, 2014 at 4:09 PM, Richard Biener
wrote:
> On Tue, Mar 18, 2014 at 4:03 PM, Ulrich Drepper wrote:
>> On Tue, Mar 18, 2014 at 7:13 AM, Richard Biener
>> wrote:
>>> extern __inline __m512
>>> __attribute__ ((__gnu_inline__, __always_inline__, __artificial__))
>>> _mm512_undefined_ps
On Tue, Mar 18, 2014 at 7:13 AM, Richard Biener
wrote:
> extern __inline __m512
> __attribute__ ((__gnu_inline__, __always_inline__, __artificial__))
> _mm512_undefined_ps (void)
> {
> __m512 __Y = __Y;
> return __Y;
> }
This provokes no warnings (as you wrote) and it doesn't clobber flags,
On Tue, Mar 18, 2014 at 10:34 AM, Ilya Tocar wrote:
> On 17 Mar 22:18, Ulrich Drepper wrote:
>> On Mon, Mar 17, 2014 at 7:39 AM, Ilya Tocar wrote:
>>
>> > undefined is similar in behavior to setzero, but it also clobbers
>> > flags. Maybe just define it to setzero for now?
>> >
>> >
>> What do yo
On 17 Mar 22:18, Ulrich Drepper wrote:
> On Mon, Mar 17, 2014 at 7:39 AM, Ilya Tocar wrote:
>
> > undefined is similar in behavior to setzero, but it also clobbers
> > flags. Maybe just define it to setzero for now?
> >
> >
> What do you mean by "clobbers flags"? Do you have an example?
I've us
On Mon, Mar 17, 2014 at 7:39 AM, Ilya Tocar wrote:
> Do you know of any cases where xor is
> generated (except for destination in gather/scatter)
I don't have any code exhibiting this handy right now. I'll keep an eye out.
> but it also clobbers
> flags. Maybe just define it to setzero for no
On 16 Mar 07:12, Ulrich Drepper wrote:
> [This patch is so far really meant for commenting. I haven't tested it
> at all yet.]
>
> Intel's intrinsic specification includes one set which currently is not
> defined in gcc's headers: the _mm*_undefined_* intrinsics.
What specification are talking ab
