[LLVMdev] Alias analysis interface

[Krzysztof Parzyszek]

On 11/9/2012 7:16 PM, Shuxin Yang wrote:
>
> The problem is: in what situations, Alias(a[i], a[i-1]) is desirable to
> return "alias", and in what situations,
> it is desirable to return "no alias".

Problem 1:
At a point during program execution where both P and Q denote valid 
memory locations, can P and Q refer to the same memory location?

Problem 2:
During the execution time of the program, does the set of memory 
locations denoted by P contain any of the memory locations denoted by Q?


With P="a[i]" and Q="a[i-1]", the answer to problem 1 is "no", while the 
answer to problem 2 is "yes".

The answer to which one you want depends on the problem you're trying to 
solve.

-Krzysztof


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