Regressions on trunk at revision 159851 vs revision 159807

[H.J. Lu]

New failures:
FAIL: gcc.dg/guality/vla-2.c  -O1  line 25 sizeof (a) == 6 * sizeof (int)
FAIL: gcc.dg/guality/vla-2.c  -O2  line 25 sizeof (a) == 6 * sizeof (int)
FAIL: gcc.dg/guality/vla-2.c  -O3 -fomit-frame-pointer  line 25 sizeof (a) == 6 * sizeof (int)
FAIL: gcc.dg/guality/vla-2.c  -O3 -g  line 25 sizeof (a) == 6 * sizeof (int)
FAIL: gcc.dg/guality/vla-2.c  -Os  line 25 sizeof (a) == 6 * sizeof (int)

New passes:
FAIL: gcc.dg/tree-ssa/prefetch-3.c scan-tree-dump-times aprefetch "unroll factor 4" 1
FAIL: gcc.dg/tree-ssa/prefetch-5.c scan-tree-dump-times aprefetch "Issued prefetch" 2
FAIL: gcc.dg/tree-ssa/prefetch-6.c scan-assembler-times prefetchnta 3
FAIL: gcc.dg/tree-ssa/prefetch-6.c scan-assembler-times prefetcht 5
FAIL: gcc.dg/tree-ssa/prefetch-6.c scan-tree-dump-times aprefetch "Issued nontemporal prefetch" 3
FAIL: gcc.dg/tree-ssa/prefetch-6.c scan-tree-dump-times aprefetch "Issued prefetch" 5
FAIL: gcc.dg/tree-ssa/prefetch-7.c scan-assembler-times mfence 2
FAIL: gcc.dg/tree-ssa/prefetch-7.c scan-assembler-times movnti 18
FAIL: gcc.dg/tree-ssa/prefetch-7.c scan-assembler-times prefetchnta 2
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
FAIL: gcc.dg/tree-ssa/prefetch-7.c scan-tree-dump-times aprefetch "Issued nontemporal prefetch" 3
FAIL: gcc.dg/tree-ssa/prefetch-7.c scan-tree-dump-times aprefetch "Issued prefetch" 5
FAIL: gcc.dg/tree-ssa/prefetch-7.c scan-tree-dump-times aprefetch "a nontemporal store" 2
FAIL: gcc.dg/tree-ssa/prefetch-7.c scan-tree-dump-times optimized "={nt}" 18
FAIL: gcc.dg/tree-ssa/prefetch-7.c scan-tree-dump-times optimized "__builtin_ia32_mfence" 2
FAIL: gcc.dg/tree-ssa/prefetch-7.c scan-tree-dump-times optimized "builtin_prefetch" 8
FAIL: gcc.dg/tree-ssa/update-unroll-1.c scan-tree-dump-not aprefetch "SUCC: 7 .100.0%"
FAIL: objc.dg/torture/tls/thr-init-3.m  -O2 -flto  (test for excess errors)
FAIL: objc.dg/torture/tls/thr-init-3.m  -O2 -fwhopr  (test for excess errors)