| ; RUN: opt -passes=loop-load-elim -S < %s | FileCheck %s |
| |
| ; Simple st->ld forwarding derived from a lexical forward dep. |
| ; |
| ; for (unsigned i = 0; i < 100; i++) { |
| ; A[i+1] = B[i] + 2; |
| ; C[i] = A[i] * 2; |
| ; } |
| |
| target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128" |
| |
| define void @f(ptr %A, ptr %B, ptr %C, i64 %N) { |
| |
| ; CHECK: for.body.lver.check: |
| ; CHECK: %found.conflict{{.*}} = |
| ; CHECK-NOT: %found.conflict{{.*}} = |
| |
| entry: |
| ; Make sure the hoisted load keeps the alignment |
| ; CHECK: %load_initial = load i32, ptr %A, align 1 |
| br label %for.body |
| |
| for.body: ; preds = %for.body, %entry |
| ; CHECK: %store_forwarded = phi i32 [ %load_initial, %for.body.ph ], [ %a_p1, %for.body ] |
| %indvars.iv = phi i64 [ 0, %entry ], [ %indvars.iv.next, %for.body ] |
| %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1 |
| |
| %Aidx_next = getelementptr inbounds i32, ptr %A, i64 %indvars.iv.next |
| %Bidx = getelementptr inbounds i32, ptr %B, i64 %indvars.iv |
| %Cidx = getelementptr inbounds i32, ptr %C, i64 %indvars.iv |
| %Aidx = getelementptr inbounds i32, ptr %A, i64 %indvars.iv |
| |
| %b = load i32, ptr %Bidx, align 4 |
| %a_p1 = add i32 %b, 2 |
| store i32 %a_p1, ptr %Aidx_next, align 4 |
| |
| %a = load i32, ptr %Aidx, align 1 |
| ; CHECK: %c = mul i32 %store_forwarded, 2 |
| %c = mul i32 %a, 2 |
| store i32 %c, ptr %Cidx, align 4 |
| |
| %exitcond = icmp eq i64 %indvars.iv.next, %N |
| br i1 %exitcond, label %for.end, label %for.body |
| |
| for.end: ; preds = %for.body |
| ret void |
| } |