| ; RUN: opt < %s -basicaa -gvn -S | FileCheck %s |
| |
| define i32 @main(i32* %p, i32 %x, i32 %y) { |
| block1: |
| %z = load i32, i32* %p |
| %cmp = icmp eq i32 %x, %y |
| br i1 %cmp, label %block2, label %block3 |
| |
| block2: |
| br label %block4 |
| |
| block3: |
| %b = bitcast i32 0 to i32 |
| store i32 %b, i32* %p |
| br label %block4 |
| |
| block4: |
| %DEAD = load i32, i32* %p |
| ret i32 %DEAD |
| } |
| |
| ; CHECK: define i32 @main(i32* %p, i32 %x, i32 %y) { |
| ; CHECK-NEXT: block1: |
| ; CHECK-NOT: %z = load i32, i32* %p |
| ; CHECK-NEXT: %cmp = icmp eq i32 %x, %y |
| ; CHECK-NEXT: br i1 %cmp, label %block2, label %block3 |
| ; CHECK: block2: |
| ; CHECK-NEXT: %DEAD.pre = load i32, i32* %p |
| ; CHECK-NEXT: br label %block4 |
| ; CHECK: block3: |
| ; CHECK-NEXT: store i32 0, i32* %p |
| ; CHECK-NEXT: br label %block4 |
| ; CHECK: block4: |
| ; CHECK-NEXT: %DEAD = phi i32 [ 0, %block3 ], [ %DEAD.pre, %block2 ] |
| ; CHECK-NEXT: ret i32 %DEAD |
| ; CHECK-NEXT: } |