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Hi, I try to understand why llvm can't optimize this small piece of code. My expectation is that the IR will be optimized to a " ret i64 2101545. But somehow the alias analysis fails when the pointer is casted to an integer value, so the dead code eliminator can't optimize it away. Could someone explain to me why this is failing and if there is a solution for that ? I can trick the

...explanation of the alias analysis queries and responses in the following talk (particularly the part starting with "AA Query" around the 22 min. mark): “Pointers, Alias & ModRef Analyses” (2018 EuroLLVM Developers’ Meeting: A. Sbirlea & N. Lopes) https://www.youtube.com/watch?v=r0XVS4Atl3U When you return `AliasResult` from your analysis you choose one: https://llvm.org/doxygen/namespacellvm.html#ae1738272abcf2ac638b97e7dc6360cfd You can see a simple example here (`TARAAResult::alias`): https://blog.tartanllama.xyz/llvm-alias-analysis/ > 2. I note that using the latest opt...

...and responses > in the following talk (particularly the part starting with "AA Query" > around the 22 min. mark): > “Pointers, Alias & ModRef Analyses” (2018 EuroLLVM Developers’ Meeting: > A. Sbirlea & N. Lopes) > https://www.youtube.com/watch?v=r0XVS4Atl3U > > When you return `AliasResult` from your analysis you choose one: > https://llvm.org/doxygen/namespacellvm.html#ae1738272abcf2ac638b97e7dc6360cfd > > You can see a simple example here (`TARAAResult::alias`): > https://blog.tartanllama.xyz/llvm-alias-analysis/...

Hey Matt, That's awesome. Thank you very much for all the information and clarification! Just a few follow up questions. Could you kindly shed some lights on it? Thank you! 1. I tried to tweak the code in the following way: - Clang [-> LLVM-IR]: https://llvm.godbolt.org/z/n9rGrs - [LLVM-IR ->] opt: https://llvm.godbolt.org/z/Uc6h5Y And i note that the outputs are: Alias sets for