| Re: [eigen] [Fwd: eigen cwise] unexpected performance regression with eigen's cwise() |
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- To: eigen@xxxxxxxxxxxxxxxxxxx
- Subject: Re: [eigen] [Fwd: eigen cwise] unexpected performance regression with eigen's cwise()
- From: Benoit Jacob <jacob.benoit.1@xxxxxxxxx>
- Date: Thu, 20 Aug 2009 01:27:22 -0400
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2009/8/20 Rohit Garg <rpg.314@xxxxxxxxx>:
> I'll ask him to try gcc 4.4 as well. But I don't see how it is
> accessing memory out of bounds. The loop in i goes from [0 , SIZE-2),
> or [0,SIZE-3], So at max, he accesses [0, SIZE-3+2] which should be
> fine.
The code is:
void doMul(){
for (int i=0;i<ITER;i++)
for (int j=0;j<SIZE-2;j++)
blah[i]=cwiseop(blah[i+1],blah[i+2]);
// blah[i]=blah[i+1].cwise()*blah[i+2];
}
the loop in i goes to ITER-1, not to SIZE-2. The i and j have been mixed up.
Benoit