llvm-project

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; RUN: opt < %s -passes=licm -S | FileCheck %s
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@b = external global i32, align 4
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@fn3.i = external global i32, align 4
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declare i32 @g() nounwind
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define i32 @f() {
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entry:
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  br label %for.cond
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for.cond:                                         ; preds = %for.end, %entry
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; CHECK-LABEL: for.cond:
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; CHECK: store i32 0, ptr @b
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  store i32 0, ptr @b, align 4
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  br i1 true, label %for.body.preheader, label %for.end
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for.body.preheader:                               ; preds = %for.cond
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  br label %for.body
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for.body:                                         ; preds = %for.body, %for.body.preheader
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  %g.15 = phi i32 [ undef, %for.body ], [ 0, %for.body.preheader ]
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  %0 = load i32, ptr @fn3.i, align 4
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  %call = call i32 @g()
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  br i1 false, label %for.body, label %for.end.loopexit
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for.end.loopexit:                                 ; preds = %for.body
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  br label %for.end
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for.end:                                          ; preds = %for.end.loopexit, %for.cond
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  %whatever = phi i32 [ %call, %for.end.loopexit ], [ undef, %for.cond ]
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  br i1 false, label %for.cond, label %if.then
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if.then:                                          ; preds = %for.end
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; CHECK-LABEL: if.then:
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; CHECK: phi i32 [ {{.*}}, %for.end ]
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; CHECK-NOT: store i32 0, ptr @b
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; CHECK: ret i32
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  ret i32 %whatever
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}
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