flashloan-rs 0.2.0

Minimal Multicall3 Flashloan Module
Documentation 
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// SPDX-License-Identifier: AGPL-3.0-only
pragma solidity >=0.8.0;

import {Bytes32AddressLib} from "./Bytes32AddressLib.sol";

/// @notice Deploy to deterministic addresses without an initcode factor.
/// @author Solmate (https://github.com/transmissions11/solmate/blob/main/src/utils/CREATE3.sol)
/// @author Modified from 0xSequence (https://github.com/0xSequence/create3/blob/master/contracts/Create3.sol)
library CREATE3 {
    using Bytes32AddressLib for bytes32;

    //--------------------------------------------------------------------------------//
    // Opcode     | Opcode + Arguments    | Description      | Stack View             //
    //--------------------------------------------------------------------------------//
    // 0x36       |  0x36                 | CALLDATASIZE     | size                   //
    // 0x3d       |  0x3d                 | RETURNDATASIZE   | 0 size                 //
    // 0x3d       |  0x3d                 | RETURNDATASIZE   | 0 0 size               //
    // 0x37       |  0x37                 | CALLDATACOPY     |                        //
    // 0x36       |  0x36                 | CALLDATASIZE     | size                   //
    // 0x3d       |  0x3d                 | RETURNDATASIZE   | 0 size                 //
    // 0x34       |  0x34                 | CALLVALUE        | value 0 size           //
    // 0xf0       |  0xf0                 | CREATE           | newContract            //
    //--------------------------------------------------------------------------------//
    // Opcode     | Opcode + Arguments    | Description      | Stack View             //
    //--------------------------------------------------------------------------------//
    // 0x67       |  0x67XXXXXXXXXXXXXXXX | PUSH8 bytecode   | bytecode               //
    // 0x3d       |  0x3d                 | RETURNDATASIZE   | 0 bytecode             //
    // 0x52       |  0x52                 | MSTORE           |                        //
    // 0x60       |  0x6008               | PUSH1 08         | 8                      //
    // 0x60       |  0x6018               | PUSH1 18         | 24 8                   //
    // 0xf3       |  0xf3                 | RETURN           |                        //
    //--------------------------------------------------------------------------------//
    bytes internal constant PROXY_BYTECODE = hex"67_36_3d_3d_37_36_3d_34_f0_3d_52_60_08_60_18_f3";

    bytes32 internal constant PROXY_BYTECODE_HASH = keccak256(PROXY_BYTECODE);

    function deploy(
        bytes32 salt,
        bytes memory creationCode,
        uint256 value
    ) internal returns (address deployed) {
        bytes memory proxyChildBytecode = PROXY_BYTECODE;

        address proxy;
        assembly {
            // Deploy a new contract with our pre-made bytecode via CREATE2.
            // We start 32 bytes into the code to avoid copying the byte length.
            proxy := create2(0, add(proxyChildBytecode, 32), mload(proxyChildBytecode), salt)
        }
        require(proxy != address(0), "DEPLOYMENT_FAILED");

        deployed = getDeployed(salt);
        (bool success, ) = proxy.call{value: value}(creationCode);
        require(success && deployed.code.length != 0, "INITIALIZATION_FAILED");
    }

    function getDeployed(bytes32 salt) internal view returns (address) {
        address proxy = keccak256(
            abi.encodePacked(
                // Prefix:
                bytes1(0xFF),
                // Creator:
                address(this),
                // Salt:
                salt,
                // Bytecode hash:
                PROXY_BYTECODE_HASH
            )
        ).fromLast20Bytes();

        return
            keccak256(
                abi.encodePacked(
                    // 0xd6 = 0xc0 (short RLP prefix) + 0x16 (length of: 0x94 ++ proxy ++ 0x01)
                    // 0x94 = 0x80 + 0x14 (0x14 = the length of an address, 20 bytes, in hex)
                    hex"d6_94",
                    proxy,
                    hex"01" // Nonce of the proxy contract (1)
                )
            ).fromLast20Bytes();
    }
}