llvm-6502/test/Transforms/SimplifyCFG/PhiEliminate.ll

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; Test a bunch of cases where the cfg simplification code should
; be able to fold PHI nodes into computation in common cases. Folding the PHI
; nodes away allows the branches to be eliminated, performing a simple form of
; 'if conversion'.
; RUN: opt < %s -simplifycfg -S > %t.xform
; RUN: not grep phi %t.xform
; RUN: grep ret %t.xform
declare void @use(i1)
declare void @use.upgrd.1(i32)
define void @test2(i1 %c, i1 %d, i32 %V, i32 %V2) {
; <label>:0
br i1 %d, label %X, label %F
X: ; preds = %0
br i1 %c, label %T, label %F
T: ; preds = %X
br label %F
F: ; preds = %T, %X, %0
%B1 = phi i1 [ true, %0 ], [ false, %T ], [ false, %X ] ; <i1> [#uses=1]
%I7 = phi i32 [ %V, %0 ], [ %V2, %T ], [ %V2, %X ] ; <i32> [#uses=1]
call void @use( i1 %B1 )
call void @use.upgrd.1( i32 %I7 )
ret void
}
define void @test(i1 %c, i32 %V, i32 %V2) {
; <label>:0
br i1 %c, label %T, label %F
T: ; preds = %0
br label %F
F: ; preds = %T, %0
%B1 = phi i1 [ true, %0 ], [ false, %T ] ; <i1> [#uses=1]
%I6 = phi i32 [ %V, %0 ], [ 0, %T ] ; <i32> [#uses=1]
call void @use( i1 %B1 )
call void @use.upgrd.1( i32 %I6 )
ret void
}