The fix for PR40551 made me realise that there are some assignment
optimizations that are missed:
integer :: array (3, 3), source (3, 3)
array = 0
array(:, 1) = 0 ! could use __builtin_memcpy
array(1,:) = 0
source = array ! uses __builtin_memcpy
source(:,1) = array (:,2) ! could use __builtin_memcpy
source(1,:) = array (2,:)
source = reshape ([1,2,3,4,5,6,7,8,9],[3,3]) ! uses __builtin_memcpy
array(:,1) = [1,2,3] ! could use __builtin_memcpy
end
At present, there is only a test that the lhs array is full. Any contiguous
reference could take these opportunities too. Some work will be required with
the helper functions but this is not a big deal.
I'll take it on.
Paul
--
Summary: Some missed optimizations in array assignment
Product: gcc
Version: 4.5.0
Status: UNCONFIRMED
Keywords: missed-optimization
Severity: normal
Priority: P3
Component: fortran
AssignedTo: pault at gcc dot gnu dot org
ReportedBy: pault at gcc dot gnu dot org
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=40598
