[Bug tree-optimization/44955] New: over-prefetched for arrays of complex number
changpeng dot fang at amd dot com
gcc-bugzilla@gcc.gnu.org
Thu Jul 15 17:12:00 GMT 2010
While I am working on prefetching-incurred performance degradation on
168.wupwise, I find that complex arrays are always over-prefetched.
Prefetches are generated for both the real part and imagine part.
subroutine s311 (i,j,n,m,beta,a,b)
c
c reductions
c sum reduction
c
integer n, i, j, beta, m
complex a(n,n), b(n,n)
do 1 j = 1,n
do 10 i = 1,m
a(i,j) = a(i,j) + beta * b(i,j)
10 continue
1 continue
return
end
For this example, two prefetches are generated for a, and two prefetches for
b.
--
Summary: over-prefetched for arrays of complex number
Product: gcc
Version: 4.6.0
Status: UNCONFIRMED
Severity: normal
Priority: P3
Component: tree-optimization
AssignedTo: unassigned at gcc dot gnu dot org
ReportedBy: changpeng dot fang at amd dot com
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=44955
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