fold_Expr: add rules
   Xor8/16/32/64(0,t) ==> t
   Xor8/16/32/64(t,0) ==> t


git-svn-id: svn://svn.valgrind.org/vex/trunk@3094 8f6e269a-dfd6-0310-a8e1-e2731360e62c
1 file changed