PUSH0 Opcode Compatibility Checker

WHAT IT DOES

PUSH0 Opcode Compatibility Checker analyzes smart contract bytecode to detect usage of the PUSH0 opcode (0x5F), introduced in EIP-3855, and assesses compatibility with target networks. It retrieves on-chain contract bytecode via eth_getCode and fetches verified source code and ABI from block explorer APIs. The tool performs opcode-level scanning for PUSH0 occurrences, identifies the functions and code paths that contain them, and estimates the compiler version likely used based on bytecode patterns. It then cross-references the detected PUSH0 usage against the target network's support status for EIP-3855, providing a compatibility assessment. The output includes a compatibility status (Compatible, Partial Support, or Incompatible), a count of PUSH0 occurrences, estimated compiler version, EIP-3855 support status for the selected network, a detailed list of detected PUSH0 locations with context, and actionable recommendations for ensuring compatibility across all target networks. This enables developers to identify potential deployment issues before they occur, particularly when deploying contracts to networks that may not yet support the PUSH0 opcode.

HOW TO USE

Connect your BGWallet to the target EVM chain. Paste the address of the contract you wish to check for PUSH0 compatibility. Optionally supply a GitHub repository URL to pull compiler version information and compatibility notes for additional context. The tool fetches the contract's bytecode, performs opcode disassembly, and scans for PUSH0 instructions. It analyzes the context of each occurrence to determine function locations and usage patterns. Review the compatibility status for your network, the count of PUSH0 occurrences, the estimated compiler version, and the list of detected occurrences. Use the analysis to determine whether your contract is compatible with your target network, and follow the recommendations to address any compatibility issues—such as replacing PUSH0 with PUSH1 0 for broader compatibility or verifying network support.

OPCODE DISASSEMBLY AND COMPILER FINGERPRINTING ENGINE

The real technical mechanism is the opcode disassembly and compiler fingerprinting engine that combines bytecode scanning with compiler version detection. The tool first disassembles the entire deployed bytecode into its constituent opcodes, then scans for the PUSH0 opcode (0x5F) across the entire codebase. For each occurrence, it traces backward through the disassembled code to identify the function that contains it, using control flow analysis to map opcode sequences to function boundaries. The engine also performs compiler fingerprinting by analyzing characteristic bytecode patterns that correspond to specific Solidity compiler versions—PUSH0 was introduced in Solidity 0.8.20 and later, so its presence suggests that the contract was compiled with a recent compiler version. The tool then cross-references the detected PUSH0 usage against a database of network support for EIP-3855, which varies across EVM chains: Ethereum Mainnet, Optimism, Polygon, Arbitrum, and Base support PUSH0, while BNB Chain and Gnosis have partial or unconfirmed support. The engine also detects edge cases where PUSH0 appears in data sections (e.g., as part of constant data or jump tables) rather than in executable code, filtering out false positives. This approach provides developers with a clear, actionable compatibility assessment that prevents deployment failures on networks that do not support PUSH0.

WHAT IT CANNOT SEE

This tool cannot detect all PUSH0 usages without access to contract bytecode or source code. It is limited by your RPC provider's rate limits for bytecode retrieval, which may delay analysis on congested networks. It cannot determine if PUSH0 is executed at runtime versus merely present in bytecode—some occurrences may be in unreachable code paths that never execute, but the tool flags them regardless. The detection relies on the completeness of the ABI and source code verification; unverified contracts or incomplete verification data will produce incomplete or inaccurate results. Detection is based on bytecode pattern matching and may miss obfuscated or indirect usages, such as PUSH0 called via DELEGATECALL or through inline assembly that obscures the opcode. The tool cannot assess the impact of PUSH0 removal or replacement without execution context—some contracts may rely on PUSH0 for gas optimization or specific stack operations. It may produce false positives for opcodes that appear in data sections rather than code, such as in constant data arrays or jump tables. The tool does not execute the contract to validate compatibility, so it cannot confirm whether PUSH0 execution would succeed or fail on the target network. It cannot account for network-specific PUSH0 support status or compiler version details beyond the available metadata.

PLEASE NOTE

This tool works exclusively with EVM-compatible chains. It requires active internet connectivity to access block explorer APIs and RPC endpoints. Some block explorers may require API keys for high-volume bytecode retrieval. The tool is read-only and does not modify or deploy any code—it only produces compatibility assessments. PUSH0 support varies by network; always verify compatibility with all target networks before deployment. Contracts compiled with Solidity 0.8.20 or later may contain PUSH0; consider using PUSH1 0 instead for maximum compatibility.