WithdrawDAO Balance Split

Deployed July 25, 2016 (block 1951725) by Vitalik Buterin (0x1db3439a22ee7c4d034e9b26437d3960b5af0517), five days after the DAO hard fork. Written in Serpent. Both the 158-byte runtime and the 176-byte creation bytecode reproduce byte-for-byte from the reconstructed source using ethereum/serpent at commit 9dc8c1c (commits 9cec73c and 0a7a488 also match).

How it works: split(addr1, addr2) reads the ETH balance of the WithdrawDAO refund contract (0xbf4ed7b27f1d666546e30d74d50d173d20bca754). If that balance is greater than 1,000,000 ETH (1e24 wei), the contract forwards its entire balance to addr1; otherwise it forwards to addr2. Both branches send balance(self), the contract's full balance, via a raw call with a zero gas stipend.

The 1,000,000-ETH threshold works as a switch on how far the DAO refund had progressed: WithdrawDAO was funded with the recovered ETH and drained as token holders withdrew, so the branch taken depends on whether enough had already been withdrawn at call time.

This is the on-chain sibling of the verified Serpent forwarder 0x6e9ccd1496ef424cb1e75eb1422eaac4d0aee851. The two differ only in the evaluation order of the call arguments: this deployment writes call(0, addr, balance(self), ...) where the sibling writes call(0, balance(self), addr, ...), which swaps two adjacent PUSH sequences inside the emitted CALL.