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; 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: }
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