[Bug target/57954] AVX missing vxorps (zeroing) before vcvtsi2s %edx, slow down AVX code

[vincenzo.innocente at cern dot ch]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=57954

--- Comment #5 from vincenzo Innocente <vincenzo.innocente at cern dot ch> ---
confirmed that the patch fixes the issue
c++ -O2 -march=corei7-avx polyAVX.cpp
time ./a.out
10358474048
2.965u 0.001s 0:02.97 99.6%    0+0k 0+0io 146pf+0w