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; Test merging of blocks that only have PHI nodes in them
;
; RUN: opt < %s -simplifycfg -S | FileCheck %s
;
define i32 @test(i1 %a, i1 %b) {
; CHECK: br i1 %a
br i1 %a, label %M, label %O
; CHECK: O:
O: ; preds = %0
; CHECK: select i1 %b, i32 0, i32 1
; CHECK-NOT: phi
br i1 %b, label %N, label %Q
Q: ; preds = %O
br label %N
N: ; preds = %Q, %O
; This block should be foldable into M
%Wp = phi i32 [ 0, %O ], [ 1, %Q ] ; <i32> [#uses=1]
br label %M
M: ; preds = %N, %0
; CHECK: %W = phi i32
%W = phi i32 [ %Wp, %N ], [ 2, %0 ] ; <i32> [#uses=1]
%R = add i32 %W, 1 ; <i32> [#uses=1]
ret i32 %R
}
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