Regressions on trunk at revision 247898 vs revision 247880

[H.J. Lu Intel64 Core i7]

New failures:
FAIL: gcc.dg/guality/pr54693-2.c   -Os  line 21 i == v + 1
FAIL: gcc.target/i386/cadd.c scan-assembler sbb

New passes:
FAIL: gcc.dg/guality/pr54693-2.c   -Os  line 21 x == 10 - i
FAIL: gcc.dg/guality/pr54693-2.c   -Os  line 21 y == 20 - 2 * i