[Bug target/53399] "*ffs" pattern generates wrong code with BMI enabled

[hjl.tools at gmail dot com]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=53399

H.J. Lu <hjl.tools at gmail dot com> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
            Summary|"*ffs" pattern generates    |"*ffs" pattern generates
                   |wrong code with BMI enabled |wrong code with BMI enabled
                   |(for corner cases)          |

--- Comment #8 from H.J. Lu <hjl.tools at gmail dot com> 2012-05-20 16:18:25 UTC ---
BSF and tzcnt are different with zero input.
BSF sets ZF with zero input and tzcnt set CF
with zero input.