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1; RUN: opt -simplifycfg -S < %s | FileCheck %s
2
3; It's not worthwhile to if-convert one of the phi nodes and leave
4; the other behind, because that still requires a branch. If
5; SimplifyCFG if-converts one of the phis, it should do both.
6
7; CHECK:      %div.high.addr.0 = select i1 %cmp1, i32 %div, i32 %high.addr.0
8; CHECK-NEXT: %low.0.add2 = select i1 %cmp1, i32 %low.0, i32 %add2
9; CHECK-NEXT: br label %while.cond
10
11define i32 @upper_bound(i32* %r, i32 %high, i32 %k) nounwind {
12entry:
13  br label %while.cond
14
15while.cond:                                       ; preds = %if.then, %if.else, %entry
16  %high.addr.0 = phi i32 [ %high, %entry ], [ %div, %if.then ], [ %high.addr.0, %if.else ]
17  %low.0 = phi i32 [ 0, %entry ], [ %low.0, %if.then ], [ %add2, %if.else ]
18  %cmp = icmp ult i32 %low.0, %high.addr.0
19  br i1 %cmp, label %while.body, label %while.end
20
21while.body:                                       ; preds = %while.cond
22  %add = add i32 %low.0, %high.addr.0
23  %div = udiv i32 %add, 2
24  %idxprom = zext i32 %div to i64
25  %arrayidx = getelementptr inbounds i32, i32* %r, i64 %idxprom
26  %0 = load i32, i32* %arrayidx
27  %cmp1 = icmp ult i32 %k, %0
28  br i1 %cmp1, label %if.then, label %if.else
29
30if.then:                                          ; preds = %while.body
31  br label %while.cond
32
33if.else:                                          ; preds = %while.body
34  %add2 = add i32 %div, 1
35  br label %while.cond
36
37while.end:                                        ; preds = %while.cond
38  ret i32 %low.0
39}
40