Regressions on trunk at revision 253719 vs revision 253704

[H.J. Lu x32 -fpic]

New failures:

New passes:
FAIL: gcc.dg/graphite/interchange-4.c execution test
FAIL: gfortran.dg/graphite/interchange-3.f90   -O   scan-tree-dump graphite "tiled"
FAIL: gfortran.dg/graphite/pr68279.f90   -O  (internal compiler error)
FAIL: gfortran.dg/graphite/pr68279.f90   -O  (test for excess errors)