xref: /llvm-project/llvm/test/Transforms/LoopLoadElim/convergent.ll (revision 055fb7795aa219a3d274d280ec9129784f169f56)
1; RUN: opt -passes=loop-load-elim -S < %s | FileCheck %s
2
3; Simple st->ld forwarding derived from a lexical forward dep, but
4; can't introduce runtime checks with a convergent call.
5;
6;   for (unsigned i = 0; i < 100; i++) {
7;     A[i+1] = convergent(B[i]) + 2;
8;     C[i] = A[i] * 2;
9;   }
10
11target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
12
13; CHECK-LABEL: @f_convergent(
14; CHECK: call i32 @llvm.convergent(
15; CHECK-NOT: call i32 @llvm.convergent(
16define void @f_convergent(ptr %A, ptr %B, ptr %C, i64 %N) #0 {
17
18entry:
19  br label %for.body
20
21for.body:                                         ; preds = %for.body, %entry
22  %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ]
23  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
24
25  %Aidx_next = getelementptr inbounds i32, ptr %A, i64 %indvars.iv.next
26  %Bidx = getelementptr inbounds i32, ptr %B, i64 %indvars.iv
27  %Cidx = getelementptr inbounds i32, ptr %C, i64 %indvars.iv
28  %Aidx = getelementptr inbounds i32, ptr %A, i64 %indvars.iv
29
30  %b = load i32, ptr %Bidx, align 4
31  %convergent.b = call i32 @llvm.convergent(i32 %b)
32
33  %a_p1 = add i32 %convergent.b, 2
34  store i32 %a_p1, ptr %Aidx_next, align 4
35
36  %a = load i32, ptr %Aidx, align 1
37  %c = mul i32 %a, 2
38  store i32 %c, ptr %Cidx, align 4
39
40  %exitcond = icmp eq i64 %indvars.iv.next, %N
41  br i1 %exitcond, label %for.end, label %for.body
42
43for.end:                                          ; preds = %for.body
44  ret void
45}
46
47declare i32 @llvm.convergent(i32) #1
48
49attributes #0 = { nounwind convergent }
50attributes #1 = { nounwind readnone convergent }
51