[Bug tree-optimization/44955] New: over-prefetched for arrays of complex number

[changpeng dot fang at amd dot com]

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