Re: Performance problem with gcc 4.9.2-3 on 64 bit

2015-02-28 Thread Bengt Larsson
Marco Atzeri wrote: On 2/27/2015 5:49 PM, Bengt Larsson wrote: Below are two benchmarks that explore maximum floating point performance. loopm6 is double precision floating point and loopm6fp is parallell single-precision. They are manually unrolled multiply-add loops. I used to reach 2.8

Re: Performance problem with gcc 4.9.2-3 on 64 bit

2015-02-27 Thread Marco Atzeri
On 2/27/2015 5:49 PM, Bengt Larsson wrote: Below are two benchmarks that explore maximum floating point performance. loopm6 is double precision floating point and loopm6fp is parallell single-precision. They are manually unrolled multiply-add loops. I used to reach 2.8 and 11 GFlops on these.

Performance problem with gcc 4.9.2-3 on 64 bit

2015-02-27 Thread Bengt Larsson
Below are two benchmarks that explore maximum floating point performance. loopm6 is double precision floating point and loopm6fp is parallell single-precision. They are manually unrolled multiply-add loops. I used to reach 2.8 and 11 GFlops on these. Now I only get 2 and 6. If you explore the