1; RUN: opt < %s -basicaa -gvn -instcombine -S | grep "ret i32 0"
2; PR4189
3@G = external constant [4 x i32]
4
5define i32 @test(i8* %p, i32 %i) nounwind {
6entry:
7	%P = getelementptr [4 x i32]* @G, i32 0, i32 %i
8	%A = load i32* %P
9	store i8 4, i8* %p
10	%B = load i32* %P
11	%C = sub i32 %A, %B
12	ret i32 %C
13}
14