| ; RUN: opt -S -O1 < %s -o %t1.ll |
| ; RUN: opt -S < %t1.ll -o %t2.ll |
| ; RUN: opt -S -passes=simplifycfg < %t1.ll -o %t3.ll |
| ;; Show that there's no difference after running another simplify CFG |
| ; RUN: diff %t2.ll %t3.ll |
| |
| ; Test from LoopSink pass, leaves some single-entry single-exit basic blocks. |
| ; After LoopSink, we get a basic block .exit.loopexit which has one entry and |
| ; one exit, the only instruction is a branch. Make sure it doesn't show up. |
| ; Make sure they disappear at -O1. |
| |
| @g = global i32 0, align 4 |
| |
| define i32 @t1(i32, i32) { |
| %3 = icmp eq i32 %1, 0 |
| br i1 %3, label %.exit, label %.preheader |
| |
| .preheader: |
| %invariant = load i32, ptr @g |
| br label %.b1 |
| |
| .b1: |
| %iv = phi i32 [ %t7, %.b7 ], [ 0, %.preheader ] |
| %c1 = icmp sgt i32 %iv, %0 |
| br i1 %c1, label %.b2, label %.b6 |
| |
| .b2: |
| %c2 = icmp sgt i32 %iv, 1 |
| br i1 %c2, label %.b3, label %.b4 |
| |
| .b3: |
| %t3 = sub nsw i32 %invariant, %iv |
| br label %.b5 |
| |
| .b4: |
| %t4 = add nsw i32 %invariant, %iv |
| br label %.b5 |
| |
| .b5: |
| %p5 = phi i32 [ %t3, %.b3 ], [ %t4, %.b4 ] |
| %t5 = mul nsw i32 %p5, 5 |
| br label %.b7 |
| |
| .b6: |
| %t6 = add nsw i32 %iv, 100 |
| br label %.b7 |
| |
| .b7: |
| %p7 = phi i32 [ %t6, %.b6 ], [ %t5, %.b5 ] |
| %t7 = add nuw nsw i32 %iv, 1 |
| %c7 = icmp eq i32 %t7, %p7 |
| br i1 %c7, label %.b1, label %.exit |
| |
| .exit: |
| ret i32 10 |
| } |
| |