This testcase causes the X86 backend to select a legal dag into an illegal input to the scheduler.  It's a 
"load folding + flag" issue.

This breaks QT.

-Chris

void %_ZN13QFSFileEngine4readEPcx() {
        %tmp201 = load int* null                ; <int> [#uses=1]
        %tmp201 = cast int %tmp201 to long              ; <long> [#uses=1]
        %tmp202 = load long* null               ; <long> [#uses=1]
        %tmp203 = add long %tmp201, %tmp202             ; <long> [#uses=1]
        store long %tmp203, long* null
        ret void
}