EIP-2935 Historical block hashes

[somnathb1]

Ref https://eips.ethereum.org/EIPS/eip-2935

[somnathb1]

On hold for a few days until EIP doc is updated

[yperbasis]

It's probably equivalent, but I find the pseudo-code in the spec easier to read. What I mean that instead of this p < window branch you have a early break in the loop. Something like:

for i := 0; i < params.BlockHashHistoryServeWindow - 1; i++ {
  ancestorNumber := parent.Number.Uint64() - 1
  if ancestorNumber == 0 { // stop at genesis block
    break
  }
  storeHash(big.NewInt(ancestorNumber), parent.ParentHash, state)
  parent = headerReader.GetHeader(parent.ParentHash, ancestorNumber)
}

[somnathb1]

It's an optimization to not have to do big.Int to uint64(), or any big.Int operation that many times

[yperbasis]

I see. Between optimization and clarity I'd choose clarity until profiling confirms that the performance degradation is material, but OK.