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; Test that LICM uses basicaa to do alias analysis, which is capable of
; disambiguating some obvious cases. If LICM is able to disambiguate the
; two pointers, then the load should be hoisted, and the store sunk. Thus
; the loop becomes empty and can be deleted by ADCE.
; RUN: llvm-upgrade < %s | llvm-as | opt -basicaa -licm --adce | llvm-dis | not grep Loop
%A = global int 7
%B = global int 8
%C = global [2 x int ] [ int 4, int 8 ]
implementation
int %test(bool %c) {
%Atmp = load int* %A
br label %Loop
Loop:
%ToRemove = load int* %A
store int %Atmp, int* %B ; Store cannot alias %A
br bool %c, label %Out, label %Loop
Out:
%X = sub int %ToRemove, %Atmp
ret int %X
}
int %test2(bool %c) {
br label %Loop
Loop:
%AVal = load int* %A
%C0 = getelementptr [2 x int ]* %C, long 0, long 0
store int %AVal, int* %C0 ; Store cannot alias %A
%BVal = load int* %B
%C1 = getelementptr [2 x int ]* %C, long 0, long 1
store int %BVal, int* %C1 ; Store cannot alias %A, %B, or %C0
br bool %c, label %Out, label %Loop
Out:
%X = sub int %AVal, %BVal
ret int %X
}
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