llvm-6502/test/Transforms/LICM/2003-05-02-LoadHoist.ll

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; This testcase tests for a problem where LICM hoists loads out of a loop
; despite the fact that calls to unknown functions may modify what is being
; loaded from. Basically if the load gets hoisted, the subtract gets turned
; into a constant zero.
;
; RUN: llvm-upgrade < %s | llvm-as | opt -licm -load-vn -gcse -instcombine | llvm-dis | grep load
%X = global int 7
declare void %foo()
int %test(bool %c) {
%A = load int *%X
br label %Loop
Loop:
call void %foo()
%B = load int *%X ;; Should not hoist this load!
br bool %c, label %Loop, label %Out
Out:
%C = sub int %A, %B
ret int %C
}