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<p class="MsoNormal">Hi,<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">I’m not clear with the aliasing rules for the pointer pointing to const memory.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">It will be great help if someone clarify my doubts.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Consider below test program:<o:p></o:p></p>
<p class="MsoNormal">int foo(int *A, int *B, const int *C, int len) {<o:p></o:p></p>
<p class="MsoNormal"> for (int i = 0; i < len; i++)<o:p></o:p></p>
<p class="MsoNormal"> A[i] = B[i] + *C;<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 this test case the type for “C” is const int * type, it means the pointer is pointing to a memory which is of type constant.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">My understanding is value at *C can’t be modified in the program, so its invariant and possibly can be hoisted.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">There is a possibility that address pointed by C can alias with the address range pointed by A.<o:p></o:p></p>
<p class="MsoNormal"><br>
But in this case since user has mentioned value pointed by C as constant so I feel aliasing should not be an issue.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Please correct if something wrong with this understanding.<o:p></o:p></p>
<p class="MsoNormal"><o:p> </o:p></p>
<p class="MsoNormal">Regards,<o:p></o:p></p>
<p class="MsoNormal">Ashutosh<o:p></o:p></p>
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