Adam Nemet | 660748c | 2016-03-09 20:47:55 +0000 | [diff] [blame] | 1 | ; RUN: opt -loop-load-elim -S < %s | FileCheck %s |
| 2 | |
| 3 | ; The accesses to A are independent here but LAA reports it as a loop-carried |
| 4 | ; forward dependence. Check that we don't perform st->ld forwarding between |
| 5 | ; them. |
| 6 | ; |
| 7 | ; for (unsigned i = 0; i < 100; i++) { |
| 8 | ; A[i][1] = B[i] + 2; |
| 9 | ; C[i] = A[i][0] * 2; |
| 10 | ; } |
| 11 | |
| 12 | target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128" |
| 13 | |
| 14 | define void @f([2 x i32]* noalias %A, i32* noalias %B, i32* noalias %C, i64 %N) { |
| 15 | |
| 16 | entry: |
| 17 | br label %for.body |
| 18 | |
| 19 | for.body: ; preds = %for.body, %entry |
| 20 | %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ] |
| 21 | %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1 |
| 22 | |
| 23 | %A1idx = getelementptr inbounds [2 x i32], [2 x i32]* %A, i64 %indvars.iv, i32 1 |
| 24 | %Bidx = getelementptr inbounds i32, i32* %B, i64 %indvars.iv |
| 25 | %Cidx = getelementptr inbounds i32, i32* %C, i64 %indvars.iv |
| 26 | %A0idx = getelementptr inbounds [2 x i32], [2 x i32]* %A, i64 %indvars.iv, i32 0 |
| 27 | |
| 28 | %b = load i32, i32* %Bidx, align 4 |
| 29 | %a_p1 = add i32 %b, 2 |
| 30 | store i32 %a_p1, i32* %A1idx, align 4 |
| 31 | |
| 32 | ; CHECK: %a = load i32, i32* %A0idx, align 4 |
| 33 | %a = load i32, i32* %A0idx, align 4 |
| 34 | ; CHECK: %c = mul i32 %a, 2 |
| 35 | %c = mul i32 %a, 2 |
| 36 | store i32 %c, i32* %Cidx, align 4 |
| 37 | |
| 38 | %exitcond = icmp eq i64 %indvars.iv.next, %N |
| 39 | br i1 %exitcond, label %for.end, label %for.body |
| 40 | |
| 41 | for.end: ; preds = %for.body |
| 42 | ret void |
| 43 | } |