Test case for ensuring correct reading back of cast constant expressions.
; This test ensures that we get a bitcast constant expression in and out,
; not a sitofp constant expression. 
; RUN: llvm-as < %s | llvm-dis | grep 'bitcast ('
%G = external global int

float %tryit(int %A) {
   ret float bitcast( int ptrtoint (int* %G to int) to float)
}