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1; This is the test case taken from Appel's book that illustrates a hard case
2; that SCCP gets right, and when followed by ADCE, is completely eliminated
3;
4; RUN: opt < %s -sccp -simplifycfg -indvars -loop-deletion -dce -simplifycfg -S | not grep br
5
6define i32 @"test function"(i32 %i0, i32 %j0) {
7BB1:
8        br label %BB2
9
10BB2:            ; preds = %BB7, %BB1
11        %j2 = phi i32 [ %j4, %BB7 ], [ 1, %BB1 ]                ; <i32> [#uses=2]
12        %k2 = phi i32 [ %k4, %BB7 ], [ 0, %BB1 ]                ; <i32> [#uses=4]
13        %kcond = icmp slt i32 %k2, 100          ; <i1> [#uses=1]
14        br i1 %kcond, label %BB3, label %BB4
15
16BB3:            ; preds = %BB2
17        %jcond = icmp slt i32 %j2, 20           ; <i1> [#uses=1]
18        br i1 %jcond, label %BB5, label %BB6
19
20BB4:            ; preds = %BB2
21        ret i32 %j2
22
23BB5:            ; preds = %BB3
24        %k3 = add i32 %k2, 1            ; <i32> [#uses=1]
25        br label %BB7
26
27BB6:            ; preds = %BB3
28        %k5 = add i32 %k2, 1            ; <i32> [#uses=1]
29        br label %BB7
30
31BB7:            ; preds = %BB6, %BB5
32        %j4 = phi i32 [ 1, %BB5 ], [ %k2, %BB6 ]                ; <i32> [#uses=1]
33        %k4 = phi i32 [ %k3, %BB5 ], [ %k5, %BB6 ]              ; <i32> [#uses=1]
34        br label %BB2
35}
36
37