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1; This testcase tests for a problem where LICM hoists loads out of a loop2; despite the fact that calls to unknown functions may modify what is being3; loaded from. Basically if the load gets hoisted, the subtract gets turned4; into a constant zero.5;6; RUN: opt < %s -passes='loop-mssa(licm),gvn,instcombine' -S | grep load7 8@X = global i32 7 ; <ptr> [#uses=2]9 10declare void @foo()11 12define i32 @test(i1 %c) {13 %A = load i32, ptr @X ; <i32> [#uses=1]14 br label %Loop15Loop: ; preds = %Loop, %016 call void @foo( )17 ;; Should not hoist this load!18 %B = load i32, ptr @X ; <i32> [#uses=1]19 br i1 %c, label %Loop, label %Out20Out: ; preds = %Loop21 %C = sub i32 %A, %B ; <i32> [#uses=1]22 ret i32 %C23}24