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1; This testcase tests for a problem where LICM hoists loads out of a loop
2; despite the fact that calls to unknown functions may modify what is being
3; loaded from.  Basically if the load gets hoisted, the subtract gets turned
4; into a constant zero.
5;
6; RUN: opt < %s -licm -gvn -instcombine -S | grep load
7
8@X = global i32 7		; <i32*> [#uses=2]
9
10declare void @foo()
11
12define i32 @test(i1 %c) {
13	%A = load i32* @X		; <i32> [#uses=1]
14	br label %Loop
15Loop:		; preds = %Loop, %0
16	call void @foo( )
17        ;; Should not hoist this load!
18	%B = load i32* @X		; <i32> [#uses=1]
19	br i1 %c, label %Loop, label %Out
20Out:		; preds = %Loop
21	%C = sub i32 %A, %B		; <i32> [#uses=1]
22	ret i32 %C
23}
24