What is case analysis?

Case analysis lets you perform timing analysis using logic constants or logic transitions on ports or pins to limit the signals propagated through the design. Setting a case analysis with a logic constant propagates the constant forward through the design, then disables paths where the constant is propagated.

Setting a case analysis with a logic transition (rising or falling) eliminates certain paths by limiting the transitions considered during analysis. Case analysis propagates the constant values specified on nets forward (but not backward) through the design.