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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">The current AliasAnalysis marks may-alias for cases when memory passed as function argument.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">i.e.<o:p></o:p></p>
<p class="MsoNormal">void foo(int *<span style="background:yellow;mso-highlight:yellow">A</span>, int *B, int *C) {<o:p></o:p></p>
<p class="MsoNormal"> for (int i=0; i<N; i++)<o:p></o:p></p>
<p class="MsoNormal"> A[i] = B[i] + C[i];<o:p></o:p></p>
<p class="MsoNormal">}<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">In the above example, it’s may-alias for memory ‘A’, because ’A’ is not known at ‘foo’ call sites.<o:p></o:p></p>
<p class="MsoNormal">Alias analysis is able to figure out memory ‘A’ is no-alias, if I modify the above test by making ‘A’ as an stack variable.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’m interested to find the cases where memory is always may-alias because of input function parameter.<o:p></o:p></p>
<p class="MsoNormal">Probably a sub category(may-alias-because-of-function-parameter) of may-alias may help.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Not sure llvm already has something to sub categorize may-alias cases.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Thanks,<o:p></o:p></p>
<p class="MsoNormal">Ashutosh<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
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