This chapter lists all Yul builtin functions supported by solx and how each is lowered to LLVM IR for the EVM backend.
Yul builtins are lowered through one of three strategies:
Direct LLVM IR : the builtin maps to native LLVM integer or memory operations on i256.LLVM intrinsic : the builtin maps to an llvm.evm.* intrinsic that the EVM backend expands to opcodes.Address space access : the builtin maps to a load or store in a typed LLVM address space (see EVM Instructions: Address Space Model ).
Builtin Lowering Notes
addDirect LLVM IR add i256subDirect LLVM IR sub i256mulDirect LLVM IR mul i256divDirect LLVM IR Unsigned; returns 0 when divisor is 0 sdivDirect LLVM IR Signed; returns 0 when divisor is 0 modDirect LLVM IR Unsigned; returns 0 when divisor is 0 smodDirect LLVM IR Signed; returns 0 when divisor is 0 addmodIntrinsic llvm.evm.addmod (x + y) % m without intermediate overflowmulmodIntrinsic llvm.evm.mulmod (x * y) % m without intermediate overflowexpIntrinsic llvm.evm.exp Exponentiation signextendIntrinsic llvm.evm.signextend Sign extend from bit (i*8+7)
Builtin Lowering Notes
ltDirect LLVM IR Unsigned less-than gtDirect LLVM IR Unsigned greater-than sltDirect LLVM IR Signed less-than sgtDirect LLVM IR Signed greater-than eqDirect LLVM IR Equality iszeroDirect LLVM IR Check if zero
Builtin Lowering Notes
andDirect LLVM IR Bitwise AND orDirect LLVM IR Bitwise OR xorDirect LLVM IR Bitwise XOR notDirect LLVM IR Bitwise NOT shlDirect LLVM IR Shift left; shift >= 256 yields 0 shrDirect LLVM IR Logical shift right; shift >= 256 yields 0 sarDirect LLVM IR Arithmetic shift right; shift >= 256 yields sign-extended value byteIntrinsic llvm.evm.byte Extract nth byte clzIntrinsic llvm.ctlz Count leading zeros (requires Osaka EVM version)
Builtin Lowering Notes
keccak256Intrinsic llvm.evm.sha3 Keccak-256 over memory range
Builtin Lowering Notes
mloadAddress space 1 load Load 32 bytes from heap memory mstoreAddress space 1 store Store 32 bytes to heap memory mstore8Intrinsic llvm.evm.mstore8 Store single byte to memory mcopymemcpy in address space 1 EIP-5656 memory copy msizeIntrinsic llvm.evm.msize Highest accessed memory index
Memory builtins are subject to LLVM memory optimizations. Operations that do not change memory contents may be removed even when they would have affected gas or msize(). See Optimizer and Assembly Semantics .
Builtin Lowering Notes
sloadAddress space 5 load Load from persistent storage sstoreAddress space 5 store Store to persistent storage tloadAddress space 6 load Load from transient storage (EIP-1153) tstoreAddress space 6 store Store to transient storage (EIP-1153)
Builtin Lowering Notes
loadimmutableIntrinsic llvm.evm.loadimmutable Load immutable value with metadata identifier setimmutableSpecial Set immutable value during deployment
Builtin Lowering Notes
calldataloadAddress space 2 load Load 32 bytes from calldata calldatasizeIntrinsic llvm.evm.calldatasize Size of calldata calldatacopymemcpy from address space 2 to 1 Copy calldata to memory returndatasizeIntrinsic llvm.evm.returndatasize Size of return data returndatacopymemcpy from address space 3 to 1 Copy return data to memory
Builtin Lowering Notes
codesizeIntrinsic llvm.evm.codesize Current contract code size codecopymemcpy from address space 4 to 1 Copy code to memory extcodesizeIntrinsic llvm.evm.extcodesize External contract code size extcodecopyIntrinsic llvm.evm.extcodecopy Copy external code to memory extcodehashIntrinsic llvm.evm.extcodehash Hash of external contract code
Builtin Lowering Notes
datasizeIntrinsic llvm.evm.datasize Size of a named data object dataoffsetIntrinsic llvm.evm.dataoffset Offset of a named data object datacopySame as codecopy Copy data to memory
These builtins are used by deploy stubs to reference embedded runtime and dependency objects. See Binary Layout for details.
Builtin Lowering Notes
log0Intrinsic llvm.evm.log0 Log with 0 topics log1Intrinsic llvm.evm.log1 Log with 1 topic log2Intrinsic llvm.evm.log2 Log with 2 topics log3Intrinsic llvm.evm.log3 Log with 3 topics log4Intrinsic llvm.evm.log4 Log with 4 topics
Builtin Lowering Notes
callIntrinsic llvm.evm.call Call with value transfer delegatecallIntrinsic llvm.evm.delegatecall Call preserving caller and callvalue staticcallIntrinsic llvm.evm.staticcall Read-only call
Note: callcode is rejected at compile time. Use delegatecall instead.
Builtin Lowering Notes
createIntrinsic llvm.evm.create Create new contract create2Intrinsic llvm.evm.create2 Create at deterministic address
Builtin Lowering Notes
returnIntrinsic llvm.evm.return Return data from execution revertIntrinsic llvm.evm.revert Revert with return data stopIntrinsic llvm.evm.stop Stop execution invalidIntrinsic llvm.evm.invalid Invalid instruction (consumes all gas)
Note: selfdestruct is rejected at compile time (deprecated by EIP-6049).
Builtin Lowering Notes
addressIntrinsic llvm.evm.address Current contract address callerIntrinsic llvm.evm.caller Message sender callvalueIntrinsic llvm.evm.callvalue Wei sent with call gasIntrinsic llvm.evm.gas Remaining gas gaspriceIntrinsic llvm.evm.gasprice Gas price of transaction balanceIntrinsic llvm.evm.balance Balance of address selfbalanceIntrinsic llvm.evm.selfbalance Current contract balance originIntrinsic llvm.evm.origin Transaction sender
Builtin Lowering Notes
blockhashIntrinsic llvm.evm.blockhash Hash of given block numberIntrinsic llvm.evm.number Current block number timestampIntrinsic llvm.evm.timestamp Block timestamp coinbaseIntrinsic llvm.evm.coinbase Block beneficiary difficultyIntrinsic llvm.evm.difficulty Block difficulty (pre-merge) prevrandaoIntrinsic llvm.evm.difficulty Previous RANDAO value (EIP-4399, reuses difficulty) gaslimitIntrinsic llvm.evm.gaslimit Block gas limit chainidIntrinsic llvm.evm.chainid Chain ID (EIP-1344) basefeeIntrinsic llvm.evm.basefee Base fee per gas (EIP-1559) blobhashRejected at compile time Versioned hash of transaction's i-th blob (EIP-4844) blobbasefeeRejected at compile time Current block's blob base fee (EIP-7516/EIP-4844)
Note: blobhash and blobbasefee are not yet supported and will produce a compile error.
Builtin Lowering Notes
popOptimized away No code generated linkersymbolIntrinsic llvm.evm.linkersymbol Library linker placeholder memoryguardSpecial Reserves a memory region; used by solx to configure the spill area for stack-too-deep mitigation