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1; RUN: llc -disable-preheader-prot=true -disable-machine-licm -machine-sink-bfi=true -mtriple=x86_64-apple-darwin < %s | FileCheck %s -check-prefix=MSINK_BFI
2; RUN: llc -disable-preheader-prot=true -disable-machine-licm -machine-sink-bfi=false -mtriple=x86_64-apple-darwin < %s | FileCheck %s -check-prefix=MSINK_NOBFI
3
4; Test that by changing BlockFrequencyInfo we change the order in which
5; machine-sink looks for sucessor blocks. By not using BFI, both G and B
6; have the same loop depth and no instructions is sinked - B is selected but
7; can't be used as to avoid breaking a non profitable critical edge. By using
8; BFI, "mul" is sinked into the less frequent block G.
9define i32 @sink_freqinfo(i32 %a, i32 %b) nounwind uwtable ssp {
10; MSINK_BFI-LABEL: sink_freqinfo
11; MSINK_BFI: jl
12; MSINK_BFI-NEXT: ## BB#
13; MSINK_BFI-NEXT: imull
14
15; MSINK_NOBFI-LABEL: sink_freqinfo
16; MSINK_NOBFI: imull
17; MSINK_NOBFI: jl
18entry:
19  br label %B
20
21B:
22  %ee = phi i32 [ 0, %entry ], [ %inc, %F ]
23  %xx = sub i32 %a, %ee
24  %cond0 = icmp slt i32 %xx, 0
25  br i1 %cond0, label %F, label %exit, !prof !0
26
27F:
28  %inc = add nsw i32 %xx, 2
29  %aa = mul nsw i32 %b, %inc
30  %exitcond = icmp slt i32 %inc, %a
31  br i1 %exitcond, label %B, label %G, !prof !1
32
33G:
34  %ii = add nsw i32 %aa, %a
35  %ll = add i32 %b, 45
36  %exitcond2 = icmp sge i32 %ii, %b
37  br i1 %exitcond2, label %G, label %exit, !prof !2
38
39exit:
40  ret i32 0
41}
42
43!0 = !{!"branch_weights", i32 4, i32 1}
44!1 = !{!"branch_weights", i32 128, i32 1}
45!2 = !{!"branch_weights", i32 1, i32 1}
46