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kernel_atax: Add comments to the second iteration

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Steffo 2022-11-16 01:43:49 +01:00
parent 57fe10ad6a
commit e891286291
Signed by: steffo
GPG key ID: 6965406171929D01
1 changed files with 9 additions and 7 deletions
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16
OpenMP/linear-algebra/kernels/atax/atax.c
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@ -69,17 +69,19 @@ static void kernel_atax(int nx, int ny,
for (i = 0; i < _PB_NY; i++)
y[i] = 0;
// TODO: Optimizable loop, no dependencies
// actually tmp[i] could be a local variable
for (i = 0; i < _PB_NX; i++)
tmp[i] = 0;
// TODO: what do we do here?
/// This computes... something? I guess whatever ATAX is?
// Trying to parallelize this only seems to increase the time required
for (i = 0; i < _PB_NX; i++)
{
/// Every iteration has its own tmp variable
tmp[i] = 0;
for (j = 0; j < _PB_NY; j++)
tmp[i] = tmp[i] + A[i][j] * x[j];
/// Which gets increased by a bit on every iteration
tmp[i] += A[i][j] * x[j];
for (j = 0; j < _PB_NY; j++)
/// Which is later used for [something else]
y[j] = y[j] + A[i][j] * tmp[i];
}
}