Maybe this could be handled by the Middle End, once the array operations in the ME are implemented. This would save us from checking the alias information in the FE.
Regarding the "Middle-End Array Expressions", see: http://www.gccsummit.org/2008/gcc-2008-proceedings.pdf, pp. 33-42. * * * From: http://gcc.gnu.org/ml/fortran/2008-07/msg00166.html PS The example from Daniel, SUBROUTINE sub(I) REAL, PARAMETER :: PI = 3.1415 REAL, DIMENSION(:), POINTER :: I I = 2.0 * PI**2 * I END SUBROUTINE produces a temporary because the scalarizer makes no attempt to resolve pointers, for obvious reasons. We could add a check that the only pointer on the rhs is the same as that on the lhs, with no dependencies, and that there are no targets in the rhs expression. -- Summary: Unneccessary array temporary for same_array = scalar * same_array Product: gcc Version: 4.4.0 Status: UNCONFIRMED Keywords: missed-optimization Severity: enhancement Priority: P3 Component: fortran AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: burnus at gcc dot gnu dot org http://gcc.gnu.org/bugzilla/show_bug.cgi?id=36915
