| ; RUN: opt -passes=loop-distribute -enable-loop-distribute -S < %s | FileCheck %s |
| |
| ; When emitting the memchecks for: |
| ; |
| ; for (i = 0; i < n; i++) { |
| ; A[i + 1] = A[i] * B[i]; |
| ; ======================= |
| ; C[i] = D[i] * E[i]; |
| ; } |
| ; |
| ; we had a bug when expanding the bounds for A and C. These are expanded |
| ; multiple times and rely on the caching in SCEV expansion to avoid any |
| ; redundancy. However, due to logic in SCEVExpander::ReuseOrCreateCast, we |
| ; can get earlier expanded values invalidated when casts are used. This test |
| ; ensure that we are not using the invalidated values. |
| |
| target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128" |
| |
| define void @f(ptr %a1, ptr %a2, |
| ptr %b, |
| ptr %c1, ptr %c2, |
| ptr %d, |
| ptr %e) { |
| entry: |
| |
| %cond = icmp eq ptr %e, null |
| br i1 %cond, label %one, label %two |
| one: |
| br label %join |
| two: |
| br label %join |
| join: |
| |
| ; The pointers need to be defined by PHIs in order for the bug to trigger. |
| ; Because of the PHIs the existing casts won't be at the desired location so a |
| ; new cast will be emitted and the old cast will get invalidated. |
| ; |
| ; These are the steps: |
| ; |
| ; 1. After the bounds for A and C are first expanded: |
| ; |
| ; join: |
| ; %a = phi i32* [ %a1, %one ], [ %a2, %two ] |
| ; %c = phi i32* [ %c1, %one ], [ %c2, %two ] |
| ; %c5 = bitcast i32* %c to i8* |
| ; %a3 = bitcast i32* %a to i8* |
| ; |
| ; 2. After A is expanded again: |
| ; |
| ; join: ; preds = %two, %one |
| ; %a = phi i32* [ %a1, %one ], [ %a2, %two ] |
| ; %c = phi i32* [ %c1, %one ], [ %c2, %two ] |
| ; %a3 = bitcast i32* %a to i8* <--- new |
| ; %c5 = bitcast i32* %c to i8* |
| ; %0 = bitcast i32* %a to i8* <--- old, invalidated |
| ; |
| ; 3. Finally, when C is expanded again: |
| ; |
| ; join: ; preds = %two, %one |
| ; %a = phi i32* [ %a1, %one ], [ %a2, %two ] |
| ; %c = phi i32* [ %c1, %one ], [ %c2, %two ] |
| ; %c5 = bitcast i32* %c to i8* <--- new |
| ; %a3 = bitcast i32* %a to i8* |
| ; %0 = bitcast i32* %c to i8* <--- old, invalidated |
| ; %1 = bitcast i32* %a to i8* |
| |
| %a = phi ptr [%a1, %one], [%a2, %two] |
| %c = phi ptr [%c1, %one], [%c2, %two] |
| br label %for.body |
| |
| ; CHECK: join |
| ; CHECK-NOT: bitcast ptr %c to ptr |
| ; CHECK-NOT: bitcast ptr %a to ptr |
| |
| for.body: ; preds = %for.body, %entry |
| %ind = phi i64 [ 0, %join ], [ %add, %for.body ] |
| |
| %arrayidxA = getelementptr inbounds i32, ptr %a, i64 %ind |
| %loadA = load i32, ptr %arrayidxA, align 4 |
| |
| %arrayidxB = getelementptr inbounds i32, ptr %b, i64 %ind |
| %loadB = load i32, ptr %arrayidxB, align 4 |
| |
| %mulA = mul i32 %loadB, %loadA |
| |
| %add = add nuw nsw i64 %ind, 1 |
| %arrayidxA_plus_4 = getelementptr inbounds i32, ptr %a, i64 %add |
| store i32 %mulA, ptr %arrayidxA_plus_4, align 4 |
| |
| %arrayidxD = getelementptr inbounds i32, ptr %d, i64 %ind |
| %loadD = load i32, ptr %arrayidxD, align 4 |
| |
| %arrayidxE = getelementptr inbounds i32, ptr %e, i64 %ind |
| %loadE = load i32, ptr %arrayidxE, align 4 |
| |
| %mulC = mul i32 %loadD, %loadE |
| |
| %arrayidxC = getelementptr inbounds i32, ptr %c, i64 %ind |
| store i32 %mulC, ptr %arrayidxC, align 4 |
| |
| %exitcond = icmp eq i64 %add, 20 |
| br i1 %exitcond, label %for.end, label %for.body |
| |
| for.end: ; preds = %for.body |
| ret void |
| } |