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; Test that GCSE uses basicaa to do alias analysis, which is capable of
; disambiguating some obvious cases. All loads should be removable in
; this testcase.
; RUN: llvm-upgrade < %s | llvm-as | opt -basicaa -load-vn -gcse -instcombine -dce | llvm-dis | not grep load
%A = global int 7
%B = global int 8
implementation
int %test() {
%A1 = load int* %A
store int 123, int* %B ; Store cannot alias %A
%A2 = load int* %A
%X = sub int %A1, %A2
ret int %X
}
int %test2() {
%A1 = load int* %A
br label %Loop
Loop:
%AP = phi int [0, %0], [%X, %Loop]
store int %AP, int* %B ; Store cannot alias %A
%A2 = load int* %A
%X = sub int %A1, %A2
%c = seteq int %X, 0
br bool %c, label %out, label %Loop
out:
ret int %X
}
declare void %external()
int %test3() {
%X = alloca int
store int 7, int* %X
call void %external()
%V = load int* %X
ret int %V
}
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