| ; RUN: opt -tbaa -basic-aa -gvn -S < %s | FileCheck %s |
| |
| target datalayout = "e-p:64:64:64" |
| |
| ; GVN should ignore the store to p1 to see that the load from p is |
| ; fully redundant. |
| |
| ; CHECK: @yes |
| ; CHECK: if.then: |
| ; CHECK-NEXT: store i32 0, i32* %q |
| ; CHECK-NEXT: ret void |
| |
| define void @yes(i1 %c, i32* %p, i32* %p1, i32* %q) nounwind { |
| entry: |
| store i32 0, i32* %p, !tbaa !1 |
| store i32 1, i32* %p1, !tbaa !2 |
| br i1 %c, label %if.else, label %if.then |
| |
| if.then: |
| %t = load i32, i32* %p, !tbaa !1 |
| store i32 %t, i32* %q |
| ret void |
| |
| if.else: |
| ret void |
| } |
| |
| ; GVN should ignore the store to p1 to see that the first load from p is |
| ; fully redundant. However, the second load uses a different type. Theoretically |
| ; the other type could be unified with the first type, however for now, GVN |
| ; should just be conservative. |
| |
| ; CHECK: @watch_out_for_type_change |
| ; CHECK: if.then: |
| ; CHECK: %t = load i32, i32* %p |
| ; CHECK: store i32 %t, i32* %q |
| ; CHECK: ret void |
| ; CHECK: if.else: |
| ; CHECK: %u = load i32, i32* %p |
| ; CHECK: store i32 %u, i32* %q |
| |
| define void @watch_out_for_type_change(i1 %c, i32* %p, i32* %p1, i32* %q) nounwind { |
| entry: |
| store i32 0, i32* %p, !tbaa !1 |
| store i32 1, i32* %p1, !tbaa !2 |
| br i1 %c, label %if.else, label %if.then |
| |
| if.then: |
| %t = load i32, i32* %p, !tbaa !3 |
| store i32 %t, i32* %q |
| ret void |
| |
| if.else: |
| %u = load i32, i32* %p, !tbaa !4 |
| store i32 %u, i32* %q |
| ret void |
| } |
| |
| ; As before, but the types are swapped. This time GVN does managed to |
| ; eliminate one of the loads before noticing the type mismatch. |
| |
| ; CHECK: @watch_out_for_another_type_change |
| ; CHECK: if.then: |
| ; CHECK: store i32 0, i32* %q |
| ; CHECK: ret void |
| ; CHECK: if.else: |
| ; CHECK: %u = load i32, i32* %p |
| ; CHECK: store i32 %u, i32* %q |
| |
| define void @watch_out_for_another_type_change(i1 %c, i32* %p, i32* %p1, i32* %q) nounwind { |
| entry: |
| store i32 0, i32* %p, !tbaa !1 |
| store i32 1, i32* %p1, !tbaa !2 |
| br i1 %c, label %if.else, label %if.then |
| |
| if.then: |
| %t = load i32, i32* %p, !tbaa !4 |
| store i32 %t, i32* %q |
| ret void |
| |
| if.else: |
| %u = load i32, i32* %p, !tbaa !3 |
| store i32 %u, i32* %q |
| ret void |
| } |
| |
| !0 = !{} |
| !1 = !{!5, !5, i64 0} |
| !2 = !{!6, !6, i64 0} |
| !3 = !{!7, !7, i64 0} |
| !4 = !{!8, !8, i64 0} |
| !5 = !{!"red", !0} |
| !6 = !{!"blu", !0} |
| !7 = !{!"outer space", !9} |
| !8 = !{!"brick red", !5} |
| !9 = !{!"observable universe"} |