Regen docs

Author: Vectorized

docs/utils/blockhashlib.md

@@ -9,6 +9,40 @@ Library for accessing block hashes way beyond the 256-block limit.
 
 <!-- customintro:start --><!-- customintro:end -->
 
+## Structs
+
+### ShortHeader
+
+```solidity
+struct ShortHeader {
+    bytes32 parentHash;
+    bytes32 stateRoot;
+    bytes32 transactionsRoot;
+    bytes32 receiptsRoot;
+    bytes32[8] logsBloom;
+}
+```
+
+Ethereum block header fields relevant to historical MPT proofs.
+
+## Custom Errors
+
+### BlockHashMismatch()
+
+```solidity
+error BlockHashMismatch()
+```
+
+The keccak256 of the RLP-encoded block header does not equal to the block hash.
+
+### InvalidBlockHeaderEncoding()
+
+```solidity
+error InvalidBlockHeaderEncoding()
+```
+
+The block header is not properly RLP-encoded.
+
 ## Constants
 
 ### HISTORY_STORAGE_ADDRESS
@@ -34,4 +68,34 @@ function blockHash(uint256 blockNumber)
 
 Retrieves the block hash for any historical block within the supported range.   
 The function gracefully handles future blocks and blocks beyond the history window by returning zero,   
-consistent with the EVM's native `BLOCKHASH` behavior.
+consistent with the EVM's native `BLOCKHASH` behavior.
+
+### verifyBlock(bytes,uint256)
+
+```solidity
+function verifyBlock(bytes calldata encodedHeader, uint256 blockNumber)
+    internal
+    view
+    returns (bytes32 result)
+```
+
+Reverts if `keccak256(encodedHeader) != blockHash(blockNumber)`,   
+where `encodedHeader` is a RLP-encoded block header.   
+Else, returns `blockHash(blockNumber)`.
+
+### toShortHeader(bytes)
+
+```solidity
+function toShortHeader(bytes calldata encodedHeader)
+    internal
+    pure
+    returns (ShortHeader memory result)
+```
+
+Retrieves the most relevant fields for MPT proofs from an RLP-encoded block header.   
+Leading fields are always present and have fixed offsets and lengths.   
+This function efficiently extracts the fields without full RLP decoding.   
+For the specification of field order and lengths, please refer to   
+prefix. 6 of the Ethereum Yellow Paper:   
+(https://ethereum.github.io/yellowpaper/paper.pdf)   
+and the Ethereum Wiki (https://epf.wiki/#/wiki/EL/RLP).