On Sat, 28 Jul 2012, Marc Glisse 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?
#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);
^
The issue seems to be that we call fold_ternary_loc with a last argument
that is a CONSTRUCTOR whereas the VEC_PERM_EXPR case expects a VECTOR_CST.
--
Marc Glisse
