{
    "Function": "concat",
    "File": "contracts/OFT/util/BytesLib.sol",
    "Parent Contracts": [],
    "High-Level Calls": [],
    "Internal Calls": [
        "mload(uint256)",
        "mstore(uint256,uint256)",
        "mstore(uint256,uint256)",
        "mstore(uint256,uint256)",
        "mload(uint256)",
        "mstore(uint256,uint256)",
        "mload(uint256)",
        "mload(uint256)",
        "mstore(uint256,uint256)",
        "mload(uint256)",
        "mload(uint256)",
        "mload(uint256)"
    ],
    "Library Calls": [],
    "Low-Level Calls": [],
    "Code": "function concat(\n        bytes memory _preBytes,\n        bytes memory _postBytes\n    )\n    internal\n    pure\n    returns (bytes memory)\n    {\n        bytes memory tempBytes;\n\n        assembly {\n        // Get a location of some free memory and store it in tempBytes as\n        // Solidity does for memory variables.\n            tempBytes := mload(0x40)\n\n        // Store the length of the first bytes array at the beginning of\n        // the memory for tempBytes.\n            let length := mload(_preBytes)\n            mstore(tempBytes, length)\n\n        // Maintain a memory counter for the current write location in the\n        // temp bytes array by adding the 32 bytes for the array length to\n        // the starting location.\n            let mc := add(tempBytes, 0x20)\n        // Stop copying when the memory counter reaches the length of the\n        // first bytes array.\n            let end := add(mc, length)\n\n            for {\n            // Initialize a copy counter to the start of the _preBytes data,\n            // 32 bytes into its memory.\n                let cc := add(_preBytes, 0x20)\n            } lt(mc, end) {\n            // Increase both counters by 32 bytes each iteration.\n                mc := add(mc, 0x20)\n                cc := add(cc, 0x20)\n            } {\n            // Write the _preBytes data into the tempBytes memory 32 bytes\n            // at a time.\n                mstore(mc, mload(cc))\n            }\n\n        // Add the length of _postBytes to the current length of tempBytes\n        // and store it as the new length in the first 32 bytes of the\n        // tempBytes memory.\n            length := mload(_postBytes)\n            mstore(tempBytes, add(length, mload(tempBytes)))\n\n        // Move the memory counter back from a multiple of 0x20 to the\n        // actual end of the _preBytes data.\n            mc := end\n        // Stop copying when the memory counter reaches the new combined\n        // length of the arrays.\n            end := add(mc, length)\n\n            for {\n                let cc := add(_postBytes, 0x20)\n            } lt(mc, end) {\n                mc := add(mc, 0x20)\n                cc := add(cc, 0x20)\n            } {\n                mstore(mc, mload(cc))\n            }\n\n        // Update the free-memory pointer by padding our last write location\n        // to 32 bytes: add 31 bytes to the end of tempBytes to move to the\n        // next 32 byte block, then round down to the nearest multiple of\n        // 32. If the sum of the length of the two arrays is zero then add\n        // one before rounding down to leave a blank 32 bytes (the length block with 0).\n            mstore(0x40, and(\n            add(add(end, iszero(add(length, mload(_preBytes)))), 31),\n            not(31) // Round down to the nearest 32 bytes.\n            ))\n        }\n\n        return tempBytes;\n    }"
}