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1; RUN: opt < %s -S -loop-unroll -unroll-threshold=50 | FileCheck %s
2
3; Make sure this loop is completely unrolled...
4; CHECK-LABEL: @test1
5; CHECK: for.body:
6; CHECK-NOT: for.end:
7
8define i32 @test1(i32* nocapture %a) nounwind uwtable readonly {
9entry:
10  br label %for.body
11
12for.body:                                         ; preds = %for.body, %entry
13  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
14  %sum.01 = phi i32 [ 0, %entry ], [ %add, %for.body ]
15  %arrayidx = getelementptr inbounds i32, i32* %a, i64 %indvars.iv
16  %0 = load i32, i32* %arrayidx, align 4
17
18  ; This loop will be completely unrolled, even with these extra instructions,
19  ; but only because they're ephemeral (and, thus, free).
20  %1 = add nsw i32 %0, 2
21  %2 = add nsw i32 %1, 4
22  %3 = add nsw i32 %2, 4
23  %4 = add nsw i32 %3, 4
24  %5 = add nsw i32 %4, 4
25  %6 = add nsw i32 %5, 4
26  %7 = add nsw i32 %6, 4
27  %8 = add nsw i32 %7, 4
28  %9 = add nsw i32 %8, 4
29  %10 = add nsw i32 %9, 4
30  %ca = icmp sgt i32 %10, -7
31  call void @llvm.assume(i1 %ca)
32
33  %add = add nsw i32 %0, %sum.01
34  %indvars.iv.next = add i64 %indvars.iv, 1
35  %lftr.wideiv = trunc i64 %indvars.iv.next to i32
36  %exitcond = icmp eq i32 %lftr.wideiv, 5
37  br i1 %exitcond, label %for.end, label %for.body
38
39for.end:                                          ; preds = %for.body
40  ret i32 %add
41}
42
43declare void @llvm.assume(i1) nounwind
44
45