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| ; RUN: opt -tbaa -basicaa -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"}
|