Regressions on trunk at revision 232864 vs revision 232798

[H.J. Lu Intel64 Core i7]

New failures:

New passes:
FAIL: gcc.dg/graphite/fuse-1.c scan-tree-dump-times forwprop4 "gimple_simplified to[^\\n]*\\^ 12" 1
FAIL: gcc.dg/graphite/fuse-1.c scan-tree-dump-times forwprop4 "gimple_simplified to[^\\n]*\\^ 12" 1
FAIL: gcc.dg/graphite/fuse-1.c scan-tree-dump-times graphite "AST generated by isl:.*for \\(int c0 = 0; c0 <= 99; c0 \\+= 1\\) {.*S_.*\\(c0\\);.*S_.*\\(c0\\);.*S_.*\\(c0\\);.*}" 1
FAIL: gcc.dg/graphite/fuse-1.c scan-tree-dump-times graphite "AST generated by isl:.*for \\(int c0 = 0; c0 <= 99; c0 \\+= 1\\) {.*S_.*\\(c0\\);.*S_.*\\(c0\\);.*S_.*\\(c0\\);.*}" 1
FAIL: gcc.dg/graphite/fuse-2.c scan-tree-dump-times graphite "AST generated by isl:.*for \\(int c0 = 0; c0 <= 99; c0 \\+= 1\\) {.*S_.*\\(c0\\);.*S_.*\\(c0\\);.*S_.*\\(c0\\);.*}" 1
FAIL: gcc.dg/graphite/fuse-2.c scan-tree-dump-times graphite "AST generated by isl:.*for \\(int c0 = 0; c0 <= 99; c0 \\+= 1\\) {.*S_.*\\(c0\\);.*S_.*\\(c0\\);.*S_.*\\(c0\\);.*}" 1