Regressions on master at commit r12-4831 vs commit r12-4824 on Linux/x86_64

[H.J. Lu]

New failures:
FAIL: gcc.dg/guality/pr36728-4.c   -O2 -flto -fuse-linker-plugin -fno-fat-lto-objects  -DPREVENT_OPTIMIZATION line 14 y == 2
FAIL: gcc.dg/guality/pr36728-4.c   -O2 -flto -fuse-linker-plugin -fno-fat-lto-objects  -DPREVENT_OPTIMIZATION line 16 y == 2
FAIL: gcc.dg/guality/pr36728-4.c   -O3 -g  -DPREVENT_OPTIMIZATION  line 16 y == 2

New passes:
FAIL: gcc.dg/vect/complex/fast-math-bb-slp-complex-add-float.c scan-tree-dump slp1 "Found COMPLEX_ADD_ROT270"
FAIL: gcc.dg/vect/complex/fast-math-bb-slp-complex-add-float.c scan-tree-dump slp1 "Found COMPLEX_ADD_ROT90"
FAIL: gcc.dg/vect/complex/fast-math-bb-slp-complex-add-pattern-float.c scan-tree-dump slp1 "Found COMPLEX_ADD_ROT270"
FAIL: gcc.dg/vect/complex/fast-math-bb-slp-complex-add-pattern-half-float.c scan-tree-dump slp1 "Found COMPLEX_ADD_ROT90"