llvm-6502/test/Analysis/BasicAA/licmtest.ll

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; Test that LICM uses basicaa to do alias analysis, which is capable of
; disambiguating some obvious cases. The ToRemove load should be eliminated
; in this testcase. This testcase was carefully contrived so that GCSE would
; not be able to eliminate the load itself, without licm's help. This is
; because, for GCSE, the load is killed by the dummy basic block.
; RUN: if as < %s | opt -basicaa -licm -gcse -simplifycfg -instcombine | dis | grep ToRemove
; RUN: then exit 1
; RUN: else exit 0
; RUN: fi
%A = global int 7
%B = global int 8
implementation
int %test(bool %c) {
%ToRemove = load int* %A
br label %Loop
Loop:
%Atmp = load int* %A
store int %Atmp, int* %B ; Store cannot alias %A
br bool %c, label %Out, label %Loop
Out:
ret int 7
Dummy:
store int 7, int* %A
br label %Loop
}