On 28 July 2012 10:26, Marc Glisse <marc.gli...@inria.fr> wrote:
> On Mon, 18 Jun 2012, Ramana Radhakrishnan wrote:
>
>> This patch following on from the fix for turning on __builtin_shuffle
>> for c++ , enables folding of vec_perm_exprs in the front-end for
>> constexpr and constructor style values.
>
>
> Hello,
>
> I took a look, and the example I gave in
> http://gcc.gnu.org/ml/gcc-patches/2012-06/msg01066.html
> although it doesn't crash the compiler anymore, still fails to compile. I am
> not sure: were you just trying to remove the ICE, or actually support this
> use?
The intent was to actually support this use properly. I'll have a look
but it's unlikely to be today.
Ramana
>
> #include <x86intrin.h>
> int main(){
> constexpr __m128d x={1.,2.};
> constexpr __m128i y={1,0};
> constexpr __m128d z=__builtin_shuffle(x,y);
> }
>
> $ g++ -std=gnu++11 m.cc
> m.cc: In function 'int main()':
> m.cc:5:23: error: '#'vec_perm_expr' not supported by dump_expr#<expression
> error>' is not a constant expression
> constexpr __m128d z=__builtin_shuffle(x,y);
> ^
>
> --
> Marc Glisse
