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1; RUN: llc -mtriple=arm-apple-ios -print-machineinstrs=branch-folder \
2; RUN: %s -o /dev/null 2>&1 | FileCheck %s
3
4; Branch probability of tailed-merged block:
5;
6; p(L0_L1 -> L2) = p(entry -> L0) * p(L0 -> L2) + p(entry -> L1) * p(L1 -> L2)
7;                = 0.2 * 0.6 + 0.8 * 0.3 = 0.36
8; p(L0_L1 -> L3) = p(entry -> L0) * p(L0 -> L3) + p(entry -> L1) * p(L1 -> L3)
9;                = 0.2 * 0.4 + 0.8 * 0.7 = 0.64
10
11; CHECK: # Machine code for function test0:
12; CHECK: Successors according to CFG: BB#{{[0-9]+}}({{[0-9a-fx/= ]+}}20.00%) BB#{{[0-9]+}}({{[0-9a-fx/= ]+}}80.00%)
13; CHECK: BB#{{[0-9]+}}:
14; CHECK: BB#{{[0-9]+}}:
15; CHECK: # End machine code for function test0.
16
17define i32 @test0(i32 %n, i32 %m, i32* nocapture %a, i32* nocapture %b) {
18entry:
19  %cmp = icmp sgt i32 %n, 0
20  br i1 %cmp, label %L0, label %L1, !prof !0
21
22L0:                                          ; preds = %entry
23  store i32 12, i32* %a, align 4
24  store i32 18, i32* %b, align 4
25  %cmp1 = icmp eq i32 %m, 8
26  br i1 %cmp1, label %L2, label %L3, !prof !1
27
28L1:                                          ; preds = %entry
29  store i32 14, i32* %a, align 4
30  store i32 18, i32* %b, align 4
31  %cmp3 = icmp eq i32 %m, 8
32  br i1 %cmp3, label %L2, label %L3, !prof !2
33
34L2:                                               ; preds = %L1, %L0
35  br label %L3
36
37L3:                                           ; preds = %L0, %L1, %L2
38  %retval.0 = phi i32 [ 100, %L2 ], [ 6, %L1 ], [ 6, %L0 ]
39  ret i32 %retval.0
40}
41
42!0 = !{!"branch_weights", i32 200, i32 800}
43!1 = !{!"branch_weights", i32 600, i32 400}
44!2 = !{!"branch_weights", i32 300, i32 700}
45