Update log computation for MSVC to match the inline assembly version.
Update log computation for MSVC to match the inline assembly version.

cherryc/dynet,Abasyoni/dynet,Peilun-Li/dynet,cherryc/dynet,Peilun-Li/dynet,Peilun-Li/dynet,cherryc/dynet,Abasyoni/dynet,Abasyoni/dynet