fixes issue 668 + skip arg setup if arg is not referenced and kept on stack
fixes issue 668
+ skip arg setup if arg is not referenced and kept on stack

git-svn-id: ed337ca7cdb08c0ba29d8fe58632bb7686892c2d@1238 49cc7528-f6fd-11dd-9d1a-b59b2e1864b6

rnk/dynamorio,rnk/dynamorio,rnk/dynamorio,rnk/dynamorio,rnk/dynamorio