Regressions on trunk at revision 239646 vs revision 239639

[H.J. Lu ia32 Core i7]

New failures:
FAIL: gcc.dg/tree-ssa/prefetch-7.c scan-assembler-times prefetchnta 1
FAIL: gcc.dg/tree-ssa/prefetch-7.c scan-assembler-times prefetcht 1
FAIL: gcc.dg/tree-ssa/prefetch-7.c scan-assembler-times prefetchw 5

New passes: