Rewrite exponentiation to bitshift #794
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The legacy codegen of Solidity uses exponentiation to simulate bitshift. This was needed back when EVM did not have left bitshift instruction. See also ethereum/solidity#16117 This pattern occurs when storing a value smaller that a storage slot size, i.e., when Solidity packs multiple values into one storage slot. We can detect this pattern and replace it with actual bitshift. This should remove one possible source of exponentiation and allow us to verify more contracts.
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msooseth
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Jul 15, 2025
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The legacy codegen of Solidity uses exponentiation to simulate bitshift. This was needed back when EVM did not have left bitshift instruction. See also ethereum/solidity#16117 This pattern occurs when storing a value smaller that a storage slot size, i.e., when Solidity packs multiple values into one storage slot.
We can detect this pattern and replace it with actual bitshift. This should remove one possible source of exponentiation and allow us to verify more contracts.
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