Regressions on trunk at revision 256561 vs revision 256525

[H.J. Lu ia32 Core i7]

New failures:

New passes:
FAIL: gcc.target/i386/pr50038.c scan-assembler-times movzbl 2 (found 3 times)
FAIL: g++.dg/ipa/devirt-22.C  -std=gnu++11  scan-ipa-dump-times cp "Discovered a virtual call to a known target" 1 (found 2 times)
FAIL: g++.dg/ipa/devirt-22.C  -std=gnu++14  scan-ipa-dump-times cp "Discovered a virtual call to a known target" 1 (found 2 times)
FAIL: g++.dg/ipa/devirt-22.C  -std=gnu++98  scan-ipa-dump-times cp "Discovered a virtual call to a known target" 1 (found 2 times)