Reduce the cost of declaring tx.to storage keys in access lists.
Currently, a transaction must read at least 25 distinct storage slots in tx.to
before it's more expensive to forego an access list.
EIP-2930 requires the address under which the storage keys reside be declared
explicitly, since it must be added to the EIP-2929 accessed_addresses list.
However, tx.to is a special case that is added by default, so paying
ACCESS_LIST_ADDRESS_COST for tx.to is essentially paying twice for the same
address. Avoiding overpayment here will reduce the differential to just 5 unique
reads before using an access list is cheaper -- making them a more attractive
option.
Treat the first occurrence of tx.to in an access list as calldata for gas
accounting purposes. Do not charge ACCESS_LIST_ADDRESS_COST for it. Storage
keys underneath the address are unaffected.
If tx.to == nil, tx.to is defined be the derived contract address created by
the transaction.
EIP-2930 is specifically written to make access lists simple to reason about and
validate. It may be possible to modify the structure of the access list to avoid
including tx.to explicitly, but this would renege on the spirit of EIP-2930.
calldata?The cost of calldata was thoroughly analyzed in EIP-2028 to determine
a fair value that is not susceptible to denial-of-service attacks. We consider
this the lower bound on how much transaction data should cost. Since there is
no computation burden imposed for adding tx.to to the accessed_addresses
map (it's added by default by EIP-2929), there is no reason to charge more than
the absolute minimum for the data.
No issues.
None.
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