feat(relayer): estimate l1 batch commit gas

[colinlyguo]

Purpose or design rationale of this PR

Describe your change. Make sure to answer these three questions: What does this PR do? Why does it do it? How does it do it?

What does this PR do?
Improving gas estimation for the relayer's batchCommit transactions to prevent exceeding the gas limit of the L1 block.

Why does it do it?
Previous gas estimation is very trivial and only acts as a placeholder.

How does it do it?
Summing gas usage of SLOAD, SSTORE, STATICCALL, keccak within batchCommit function of the contract. These operations represent the major components of gas consumption.

• calldata:
  • 16 gas per non-zero byte (Gtxdatanonzero), 4 gas per zero byte (Gtxdatazero).
  • batchCommit
  • use 16 gas per byte as an over-estimate.
• SLOAD:
  • cold sload in ScrollChain, cost 2100 gas each, 5 times
    • sload committedBatches[_batchIndex]
    • sload committedBatches[_batchIndex + 1]
    • sload isSequencer[msg.sender]
    • first-time sload variable address public messageQueue
    • sload committedBatches[_batchIndex] (write op also contains one sload)
  • cold sload in L1MessageQueue, cost 2100gas each, numL1Messages times
    • sload l1 messages
  • warm sload in ScrollChain, cost 100 gas each, numBlocks-1 times
    • not-first-time sload variable address public messageQueue
• SSTORE:
  • sstore with zero original value in ScrollChain, cost 20000 gas each, 1 time
    • sstore committedBatches[_batchIndex] = _batchHash
• STATICCALL: staticcall _messageQueue.getCrossDomainMessage
  • call to L1MessageQueue, cost 100 each, numL1Messages times
  • cold address access to L1MessageQueue, cost 2600 gas each, 1 time
  • warm address access to L1MessageQueue, cost 100 gas each, numL1Messages-1 times
• keccak: cost30 + 6 * ceil(size / 32) gas each time
  • parent batch header hash, with size: 89 + 32 * ceil(parent-batch-header-length / 256)
    • get parent batch header hash
  • current batch header hash, with size: 89 + 32 * ceil(current-batch-header-length / 256)
    • get current batch header hash
  • numChunks times chunk data hash, with size: 58 * numBlocks + 32 * numTxs
    • get chunk hash
      • 58 * numBlocks
      • 32 * numTxs
  • data hash, with size: 32 * numChunks
    • get batch data hash
  • tx hash, with size: tx payload size
    • tx payload hash

PR title

Your PR title must follow conventional commits (as we are doing squash merge for each PR), so it must start with one of the following types:

• feat: A new feature

Deployment tag versioning

Has tag in common/version.go been updated?

• No, this PR doesn't involve a new deployment, git tag, docker image tag
• Yes

Breaking change label

Does this PR have the breaking-change label?

• No, this PR is not a breaking change
• Yes

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