| ; RUN: opt -S -loop-fusion -loop-fusion-peel-max-count=3 < %s | FileCheck %s |
| |
| ; Tests that we do not fuse two guarded loops together. |
| ; These loops do not have the same trip count, and the first loop meets the |
| ; requirements for peeling. However, the exit block of the first loop makes the |
| ; loops unsafe to fuse together. |
| ; The expected output of this test is the function as below. |
| |
| ; CHECK-LABEL: void @unsafe_exitblock(i32* noalias %A, i32* noalias %B) |
| ; CHECK: for.first.guard |
| ; CHECK: br i1 %cmp3, label %for.first.preheader, label %for.second.guard |
| ; CHECK: for.first.preheader: |
| ; CHECK-NEXT: br label %for.first |
| ; CHECK: for.first: |
| ; CHECK: br i1 %cmp, label %for.first, label %for.first.exit |
| ; CHECK: for.first.exit: |
| ; CHECK-NEXT: call void @bar() |
| ; CHECK-NEXT: br label %for.second.guard |
| ; CHECK: for.second.guard: |
| ; CHECK: br i1 %cmp21, label %for.second.preheader, label %for.end |
| ; CHECK: for.second.preheader: |
| ; CHECK-NEXT: br label %for.second |
| ; CHECK: for.second: |
| ; CHECK: br i1 %cmp2, label %for.second, label %for.second.exit |
| ; CHECK: for.second.exit: |
| ; CHECK-NEXT: br label %for.end |
| ; CHECK: for.end: |
| ; CHECK-NEXT: ret void |
| |
| define void @unsafe_exitblock(i32* noalias %A, i32* noalias %B) { |
| for.first.guard: |
| %cmp3 = icmp slt i64 0, 45 |
| br i1 %cmp3, label %for.first.preheader, label %for.second.guard |
| |
| for.first.preheader: ; preds = %for.first.guard |
| br label %for.first |
| |
| for.first: ; preds = %for.first.preheader, %for.first |
| %i.04 = phi i64 [ %inc, %for.first ], [ 0, %for.first.preheader ] |
| %arrayidx = getelementptr inbounds i32, i32* %A, i64 %i.04 |
| store i32 0, i32* %arrayidx, align 4 |
| %inc = add nsw i64 %i.04, 1 |
| %cmp = icmp slt i64 %inc, 45 |
| br i1 %cmp, label %for.first, label %for.first.exit |
| |
| for.first.exit: ; preds = %for.first |
| call void @bar() |
| br label %for.second.guard |
| |
| for.second.guard: ; preds = %for.first.exit, %for.first.guard |
| %cmp21 = icmp slt i64 2,45 |
| br i1 %cmp21, label %for.second.preheader, label %for.end |
| |
| for.second.preheader: ; preds = %for.second.guard |
| br label %for.second |
| |
| for.second: ; preds = %for.second.preheader, %for.second |
| %j.02 = phi i64 [ %inc6, %for.second ], [ 2, %for.second.preheader ] |
| %arrayidx4 = getelementptr inbounds i32, i32* %B, i64 %j.02 |
| store i32 0, i32* %arrayidx4, align 4 |
| %inc6 = add nsw i64 %j.02, 1 |
| %cmp2 = icmp slt i64 %inc6, 45 |
| br i1 %cmp2, label %for.second, label %for.second.exit |
| |
| for.second.exit: ; preds = %for.second |
| br label %for.end |
| |
| for.end: ; preds = %for.second.exit, %for.second.guard |
| ret void |
| } |
| |
| declare void @bar() |