; RUN: llvm-as < %s | opt -simplifycfg | llvm-dis | \ ; RUN: not grep {call void @DEAD} ; Test that we can thread a simple known condition through switch statements. declare void @foo1() declare void @foo2() declare void @DEAD() define void @test1(i32 %V) { switch i32 %V, label %A [ i32 4, label %T i32 17, label %Done i32 1234, label %A ] ;; V == 4 if we get here. T: ; preds = %0 call void @foo1( ) ;; This switch is always statically determined. switch i32 %V, label %A2 [ i32 4, label %B i32 17, label %C i32 42, label %C ] A2: ; preds = %T call void @DEAD( ) call void @DEAD( ) ;; always true %cond2 = icmp eq i32 %V, 4 ; [#uses=1] br i1 %cond2, label %Done, label %C A: ; preds = %0, %0 call void @foo1( ) ;; always true %cond = icmp ne i32 %V, 4 ; [#uses=1] br i1 %cond, label %Done, label %C Done: ; preds = %B, %A, %A2, %0 ret void B: ; preds = %T call void @foo2( ) ;; always true %cond3 = icmp eq i32 %V, 4 ; [#uses=1] br i1 %cond3, label %Done, label %C C: ; preds = %B, %A, %A2, %T, %T call void @DEAD( ) ret void } define void @test2(i32 %V) { switch i32 %V, label %A [ i32 4, label %T i32 17, label %D i32 1234, label %E ] ;; V != 4, 17, 1234 here. A: ; preds = %0 call void @foo1( ) ;; This switch is always statically determined. switch i32 %V, label %E [ i32 4, label %C i32 17, label %C i32 42, label %D ] ;; unreacahble. C: ; preds = %A, %A call void @DEAD( ) ret void T: ; preds = %0 call void @foo1( ) call void @foo1( ) ret void D: ; preds = %A, %0 call void @foo1( ) ret void E: ; preds = %A, %0 ret void }